2762 files changed, 220659 insertions, 107785 deletions

diff --git a/.appveyor.yml b/.appveyor.yml
index c8bf89e0d6..05ff204541 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -11,23 +11,24 @@ clone_depth: 10
 platform:
   - x64
 skip_commits:
-  message: /^\[DOC\]/
+  message: /\[DOC\]/
   files:
     - doc/*
     - '**/*.md'
     - '**/*.rdoc'
+    - '**/.document'
+    - '**/*.[1-8]'
+    - '**/*.ronn'
 environment:
   ruby_version: "24-%Platform%"
-  zlib_version: "1.2.12"
   matrix:
+    # Test only the oldest supported version because AppVeyor is unstable, its concurrency
+    # is limited, and compatibility issues that happen only in newer versions are rare.
+    # You may test some other stuff on GitHub Actions instead.
     - build: vs
-      vs: 120
-      ssl: OpenSSL
-      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
-      GEMS_FOR_TEST: ""
-    - build: vs
-      vs: 140
+      vs: 120 # Visual Studio 2013
       ssl: OpenSSL-v111
+      # The worker image name. This is NOT the Visual Studio version we're using here.
       APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
       GEMS_FOR_TEST: ""
   RELINE_TEST_ENCODING: "UTF-8"
@@ -47,8 +48,9 @@ for:
     - cd C:\Tools\vcpkg
     - git pull -q
     - .\bootstrap-vcpkg.bat
+    - ps: Start-FileDownload 'https://github.com/microsoft/vcpkg-tool/releases/download/2023-08-09/vcpkg.exe' -FileName 'C:\Tools\vcpkg\vcpkg.exe'
     - cd %APPVEYOR_BUILD_FOLDER%
-    - vcpkg --triplet %Platform%-windows install libffi libyaml readline zlib
+    - vcpkg --triplet %Platform%-windows install --x-use-aria2 libffi libyaml readline zlib
     - CALL SET vcvars=%%^VS%VS%COMNTOOLS^%%..\..\VC\vcvarsall.bat
     - SET vcvars
     - '"%vcvars%" %Platform:x64=amd64%'
@@ -68,9 +70,6 @@ for:
     - mkdir \usr\local\bin
     - mkdir \usr\local\include
     - mkdir \usr\local\lib
-    - SET ZLIB_ZIP=.downloaded-cache\zlib%zlib_version:.=%.zip
-    - if not exist %ZLIB_ZIP% curl -fsSL -o %ZLIB_ZIP% --retry 10 https://zlib.net/zlib%zlib_version:.=%.zip
-    - 7z x -aos -o%APPVEYOR_BUILD_FOLDER%\ext\zlib %ZLIB_ZIP%
     - for %%I in (%OPENSSL_DIR%\*.dll) do mklink /h \usr\local\bin\%%~nxI %%I
     - for %%I in (c:\Tools\vcpkg\installed\%Platform%-windows\bin\*.dll) do (
         if not %%~nI == readline mklink \usr\local\bin\%%~nxI %%I
@@ -78,6 +77,7 @@ for:
     - attrib +r /s /d
     - mkdir %Platform%-mswin_%vs%
   build_script:
+    - set HAVE_GIT=no
     - cd %APPVEYOR_BUILD_FOLDER%
     - cd %Platform%-mswin_%vs%
     - >-
@@ -94,7 +94,7 @@ for:
     - nmake -l "TESTOPTS=-v -q" btest
     - nmake -l "TESTOPTS=-v -q" test-basic
     - >-
-      nmake -l "TESTOPTS=-v --timeout-scale=3.0
+      nmake -l "TESTOPTS=--timeout-scale=3.0
       --excludes=../test/excludes/_appveyor -j%JOBS%
       --exclude win32ole
       --exclude test_bignum
@@ -105,7 +105,7 @@ for:
     # separately execute tests without -j which may crash worker with -j.
     - >-
       nmake -l
-      "TESTOPTS=-v --timeout-scale=3.0 --excludes=../test/excludes/_appveyor"
+      "TESTOPTS=--timeout-scale=3.0 --excludes=../test/excludes/_appveyor"
       TESTS="
       ../test/win32ole
       ../test/ruby/test_bignum.rb
@@ -123,7 +123,7 @@ notifications:
       {{^isPullRequest}}
         {
           "ci": "AppVeyor CI",
-          "env": "Visual Studio 2013 / 2015",
+          "env": "Visual Studio 2013",
           "url": "{{buildUrl}}",
           "commit": "{{commitId}}",
           "branch": "{{branch}}"
diff --git a/.cirrus.yml b/.cirrus.yml
deleted file mode 100644
index 0cab0023c2..0000000000
--- a/.cirrus.yml
+++ /dev/null
@@ -1,64 +0,0 @@
-# This CI is used to test Arm cases. We can set the maximum 16 tasks.
-# The entire testing design is inspired from .github/workflows/compilers.yml.
-
-# By default, Cirrus mounts an empty volume to `/tmp`
-# which triggers all sorts of warnings like "system temporary path is world-writable: /tmp".
-# Lets workaround it by specifying a custom volume mount point.
-env:
-  CIRRUS_VOLUME: /cirrus-ci-volume
-  LANG: C.UTF-8
-
-task:
-  name: Arm64 Graviton2 / $CC
-  skip: "changesIncludeOnly('doc/**', '**.{md,rdoc}')"
-  arm_container:
-    # We use the arm64 images at https://github.com/ruby/ruby-ci-image/pkgs/container/ruby-ci-image .
-    image: ghcr.io/ruby/ruby-ci-image:$CC
-    # Define the used cpu core in each matrix task. We can use total 16 cpu
-    # cores in entire matrix. [cpu] = [total cpu: 16] / [number of tasks]
-    cpu: 8
-    # We can request maximum 4 GB per cpu.
-    # [memory per task] = [memory per cpu: 4 GB] * [cpu]
-    memory: 32G
-  env:
-    CIRRUS_CLONE_DEPTH: 50
-    optflags: '-O1'
-    debugflags: '-ggdb3'
-    RUBY_PREFIX: /tmp/ruby-prefix
-    RUBY_DEBUG: ci rgengc
-    RUBY_TESTOPTS: >-
-      -q
-      --color=always
-      --tty=no
-    matrix:
-      CC: clang-12
-      CC: gcc-11
-  id_script: id
-  set_env_script:
-    # Set `GNUMAKEFLAGS`, because the flags are GNU make specific. Note using
-    # the `make` environment variable used in compilers.yml causes some rubygems
-    # tests to fail.
-    # https://github.com/rubygems/rubygems/issues/4921
-    - echo "GNUMAKEFLAGS=-s -j$((1 + $CIRRUS_CPU))" >> $CIRRUS_ENV
-  print_env_script:
-    - echo "GNUMAKEFLAGS=$GNUMAKEFLAGS"
-  # Arm containers are executed in AWS's EKS, and it's not yet supporting IPv6
-  # See https://github.com/aws/containers-roadmap/issues/835
-  disable_ipv6_script: sudo ./tool/disable_ipv6.sh
-  autogen_script: ./autogen.sh
-  configure_script: >-
-    ./configure -C
-    --enable-debug-env
-    --disable-install-doc
-    --with-ext=-test-/cxxanyargs,+
-    --prefix="$RUBY_PREFIX"
-  make_extract-extlibs_script: make extract-extlibs
-  make_incs_script: make incs
-  make_script: make
-  make_leaked-globals_script: make leaked-globals
-  make_test_script: make test
-  make_install_script: make install
-  install_gems_for_test_script: $RUBY_PREFIX/bin/gem install --no-doc timezone tzinfo
-  make_test-tool_script: make test-tool
-  make_test-all_script: make test-all
-  make_test-spec_script: make test-spec
diff --git a/.document b/.document
index 9cdd66f87a..3a6b0c238c 100644
--- a/.document
+++ b/.document
@@ -18,14 +18,18 @@ gc.rb
 io.rb
 kernel.rb
 marshal.rb
+mjit.rb
 numeric.rb
 nilclass.rb
 pack.rb
 ractor.rb
 string.rb
+symbol.rb
 timev.rb
+thread_sync.rb
 trace_point.rb
 warning.rb
+yjit.rb
 
 # the lib/ directory (which has its own .document file)
 lib
@@ -41,7 +45,6 @@ README.ja.md
 
 COPYING
 COPYING.ja
-CONTRIBUTING.md
 
 LEGAL
 
diff --git a/.gdbinit b/.gdbinit
index 8979e8b47c..34d044caf6 100644
--- a/.gdbinit
+++ b/.gdbinit
@@ -544,13 +544,13 @@ end
 
 define rp_class
   printf "(struct RClass *) %p", (void*)$arg0
-  if ((struct RClass *)($arg0))->ptr.origin_ != $arg0
-    printf " -> %p", ((struct RClass *)($arg0))->ptr.origin_
+  if RCLASS_ORIGIN((struct RClass *)($arg0)) != $arg0
+    printf " -> %p", RCLASS_ORIGIN((struct RClass *)($arg0))
   end
   printf "\n"
   rb_classname $arg0
   print/x *(struct RClass *)($arg0)
-  print *((struct RClass *)($arg0))->ptr
+  print *RCLASS_EXT((struct RClass *)($arg0))
 end
 document rp_class
   Print the content of a Class/Module.
@@ -979,8 +979,8 @@ end
 
 define rb_ps_vm
   print $ps_vm = (rb_vm_t*)$arg0
-  set $ps_thread_ln = $ps_vm->living_threads.n.next
-  set $ps_thread_ln_last = $ps_vm->living_threads.n.prev
+  set $ps_thread_ln      = $ps_vm->ractor.main_ractor.threads.set.n.next
+  set $ps_thread_ln_last = $ps_vm->ractor.main_ractor.threads.set.n.prev
   while 1
     set $ps_thread_th = (rb_thread_t *)$ps_thread_ln
     set $ps_thread = (VALUE)($ps_thread_th->self)
diff --git a/.git-blame-ignore-revs b/.git-blame-ignore-revs
new file mode 100644
index 0000000000..6c5eac5a0f
--- /dev/null
+++ b/.git-blame-ignore-revs
@@ -0,0 +1,23 @@
+# This is a file used by GitHub to ignore the following commits on `git blame`.
+#
+# You can also do the same thing in your local repository with:
+# $ git config --local blame.ignoreRevsFile .git-blame-ignore-revs
+
+# Expand tabs
+5b21e94bebed90180d8ff63dad03b8b948361089
+
+# Enable Style/StringLiterals cop for RubyGems/Bundler
+d7ffd3fea402239b16833cc434404a7af82d44f3
+
+# [ruby/digest] Revert tab-expansion in external files
+48b09aae7ec5632209229dcc294dd0d75a93a17f
+8a65cf3b61c60e4cb886f59a73ff6db44364bfa9
+39dc9f9093901d40d2998653948d5da38b18ee2c
+
+# [ruby/io-nonblock] Revert tab expansion
+f28287d34c03f472ffe90ea262bdde9affd4b965
+0d842fecb4f75ab3b1d4097ebdb8e88f51558041
+4ba2c66761d6a293abdfba409241d31063cefd62
+
+# Make benchmark indentation consistent
+fc4acf8cae82e5196186d3278d831f2438479d91
diff --git a/.github/CODEOWNERS b/.github/CODEOWNERS
deleted file mode 100644
index 15abc79af6..0000000000
--- a/.github/CODEOWNERS
+++ /dev/null
@@ -1,10 +0,0 @@
-# Lines starting with '#' are comments.
-# Each line is a file pattern followed by one or more owners.
-# Code owners will be automatically tagged as reviewers when a pull request is opened
-
-# YJIT sources and tests
-yjit* @maximecb @xrxr @tenderlove
-doc/yjit/* @maximecb @xrxr @tenderlove
-bootstraptest/test_yjit* @maximecb @xrxr @tenderlove
-test/ruby/test_yjit* @maximecb @xrxr @tenderlove
-.github/workflows/yjit* @maximecb @xrxr @tenderlove
diff --git a/.github/dependabot.yml b/.github/dependabot.yml
index b18fd29357..bc63aca35b 100644
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@@ -3,4 +3,4 @@ updates:
   - package-ecosystem: 'github-actions'
     directory: '/'
     schedule:
-      interval: 'weekly'
+      interval: 'monthly'
diff --git a/.github/workflows/baseruby.yml b/.github/workflows/baseruby.yml
index 7385fc4d9e..ebaafe3bf0 100644
--- a/.github/workflows/baseruby.yml
+++ b/.github/workflows/baseruby.yml
@@ -4,23 +4,37 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
+      - '**/.document'
   pull_request:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
   cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
 
+permissions:
+  contents: read
+
 jobs:
   baseruby:
     name: BASERUBY
-    runs-on: ubuntu-20.04
-    if: ${{ !startsWith(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    runs-on: ubuntu-22.04
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
     strategy:
       matrix:
         ruby:
@@ -34,12 +48,12 @@ jobs:
           - ruby-3.1
 
     steps:
-      - uses: actions/checkout@v3
-      - uses: actions/cache@v3
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: .downloaded-cache
           key: downloaded-cache
-      - uses: ruby/setup-ruby@v1
+      - uses: ruby/setup-ruby@13e7a03dc3ac6c3798f4570bfead2aed4d96abfb # v1.244.0
         with:
           ruby-version: ${{ matrix.ruby }}
           bundler: none
@@ -51,7 +65,7 @@ jobs:
       - run: make incs
       - run: make all
       - run: make test
-      - uses: k0kubun/action-slack@v2.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
@@ -59,7 +73,7 @@ jobs:
               "env": "${{ github.workflow }} / BASERUBY @ ${{ matrix.ruby }}",
               "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
               "commit": "${{ github.sha }}",
-              "branch": "${{ github.ref }}".split('/').reverse()[0]
+              "branch": "${{ github.ref_name }}"
             }
         env:
           SLACK_WEBHOOK_URL: ${{ secrets.SIMPLER_ALERTS_URL }} # ruby-lang slack: ruby/simpler-alerts-bot
diff --git a/.github/workflows/bundled_gems.yml b/.github/workflows/bundled_gems.yml
index 83f01d5868..070c0fa1dd 100644
--- a/.github/workflows/bundled_gems.yml
+++ b/.github/workflows/bundled_gems.yml
@@ -2,18 +2,31 @@ name: bundled_gems
 
 on:
   push:
+    branches: [ "master" ]
     paths:
       - '.github/workflows/bundled_gems.yml'
       - 'gems/bundled_gems'
   pull_request:
+    branches: [ "master" ]
+    paths:
+      - '.github/workflows/bundled_gems.yml'
+      - 'gems/bundled_gems'
+  merge_group:
+    branches: [ "master" ]
     paths:
       - '.github/workflows/bundled_gems.yml'
       - 'gems/bundled_gems'
   schedule:
     - cron: '45 6 * * *'
+  workflow_dispatch:
+
+permissions:  # added using https://github.com/step-security/secure-workflows
+  contents: read
 
 jobs:
   update:
+    permissions:
+      contents: write  # for Git to git push
     if: ${{ github.event_name != 'schedule' || github.repository == 'ruby/ruby' }}
     name: update ${{ github.workflow }}
     runs-on: ubuntu-latest
@@ -28,9 +41,9 @@ jobs:
           echo "GNUMAKEFLAGS=-j$((1 + $(nproc --all)))" >> $GITHUB_ENV
           echo "TODAY=$(date +%F)" >> $GITHUB_ENV
 
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
 
-      - uses: actions/cache@v3
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: .downloaded-cache
           key: downloaded-cache-${{ github.sha }}
@@ -50,6 +63,7 @@ jobs:
 
       - name: Maintain updated gems list in NEWS
         run: |
+          #!ruby
           require 'json'
           news = File.read("NEWS.md")
           prev = news[/since the \*+(\d+\.\d+\.\d+)\*+/, 1]
@@ -67,14 +81,14 @@ jobs:
               [g, v] unless last[g] == v
             end
             changed, added = changed.partition {|g, _| last[g]}
-            news.sub!(/^\*( +)The following #{type} gems? are updated\.\n\K(?: \1\* .*\n)*/) do
-              mark = "#{$1} * "
+            news.sub!(/^\*( +)The following #{type} gems? are updated\.\n+\K(?: \1\*( +).*\n)*/) do
+              mark = "#{$1} *#{$2}"
               changed.map {|g, v|"#{mark}#{g} #{v}\n"}.join("")
             end or next
-            news.sub!(/^\*( +)The following default gems are now bundled gems\.\n\K(?: \1\* .*\n)*/) do
-              mark = "#{$1} * "
+            news.sub!(/^\*( +)The following default gems are now bundled gems\.\n+\K(?: \1\*( +).*\n)*/) do
+              mark = "#{$1} *#{$2}"
               added.map {|g, v|"#{mark}#{g} #{v}\n"}.join("")
-            end or next if added
+            end or next unless added.empty?
             File.write("NEWS.md", news)
           end
         shell: ruby {0}
@@ -100,6 +114,11 @@ jobs:
           make
         if: ${{ steps.diff.outcome == 'failure' }}
 
+      - name: Prepare bundled gems
+        run: |
+          make -s prepare-gems
+        if: ${{ steps.diff.outcome == 'failure' }}
+
       - name: Test bundled gems
         run: |
           make -s test-bundled-gems
@@ -131,3 +150,17 @@ jobs:
           GIT_AUTHOR_NAME: git
           GIT_COMMITTER_NAME: git
         if: ${{ github.repository == 'ruby/ruby' && !startsWith(github.event_name, 'pull') && steps.show.outcome == 'failure' }}
+
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
+        with:
+          payload: |
+            {
+              "ci": "GitHub Actions",
+              "env": "${{ github.workflow }} / update",
+              "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
+              "commit": "${{ github.sha }}",
+              "branch": "${{ github.ref_name }}"
+            }
+        env:
+          SLACK_WEBHOOK_URL: ${{ secrets.SIMPLER_ALERTS_URL }} # ruby-lang slack: ruby/simpler-alerts-bot
+        if: ${{ failure() && github.event_name == 'push' }}
diff --git a/.github/workflows/check_dependencies.yml b/.github/workflows/check_dependencies.yml
index f606a86b66..79b2916feb 100644
--- a/.github/workflows/check_dependencies.yml
+++ b/.github/workflows/check_dependencies.yml
@@ -3,26 +3,40 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
+      - '**/.document'
   pull_request:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
   cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
 
+permissions:
+  contents: read
+
 jobs:
   update-deps:
     strategy:
       matrix:
-        os: [ubuntu-20.04]
+        os: [ubuntu-22.04]
       fail-fast: true
     runs-on: ${{ matrix.os }}
-    if: ${{ !startsWith(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
     steps:
       - name: Install libraries
         run: |
@@ -32,15 +46,14 @@ jobs:
         if: ${{ contains(matrix.os, 'ubuntu') }}
       - name: Install libraries
         run: |
-          brew upgrade
           brew install gmp libffi openssl@1.1 zlib autoconf automake libtool readline
         if: ${{ contains(matrix.os, 'macos') }}
       - name: git config
         run: |
           git config --global advice.detachedHead 0
           git config --global init.defaultBranch garbage
-      - uses: actions/checkout@v3
-      - uses: actions/cache@v3
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: .downloaded-cache
           key: downloaded-cache
@@ -50,7 +63,7 @@ jobs:
       - run: make all golf
       - run: ruby tool/update-deps --fix
       - run: git diff --no-ext-diff --ignore-submodules --exit-code
-      - uses: k0kubun/action-slack@v2.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
@@ -58,7 +71,7 @@ jobs:
               "env": "${{ matrix.os }} / Dependencies need to update",
               "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
               "commit": "${{ github.sha }}",
-              "branch": "${{ github.ref }}".split('/').reverse()[0]
+              "branch": "${{ github.ref_name }}"
             }
         env:
           SLACK_WEBHOOK_URL: ${{ secrets.SIMPLER_ALERTS_URL }} # ruby-lang slack: ruby/simpler-alerts-bot
diff --git a/.github/workflows/check_misc.yml b/.github/workflows/check_misc.yml
deleted file mode 100644
index 9e35d7f432..0000000000
--- a/.github/workflows/check_misc.yml
+++ /dev/null
@@ -1,97 +0,0 @@
-name: Miscellaneous checks
-on: [push, pull_request]
-
-concurrency:
-  group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
-  cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
-
-jobs:
-  checks:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v3
-      - name: Check if C-sources are US-ASCII
-        run: |
-          ! grep -r -n '[^	 -~]' *.[chy] include internal win32/*.[ch]
-      - name: Check for trailing spaces
-        run: |
-          ! git grep -n '[	 ]$' '*.rb' '*.[chy]'
-      - name: Check for header macros
-        run: |
-          ! for header in ruby/*.h; do \
-            git grep -l -F -e $header -e HAVE_`echo $header | tr a-z./ A-Z__` -- . > /dev/null || echo $header
-          done | grep -F .
-        working-directory: include
-
-      - uses: actions/cache@v3
-        with:
-          path: .downloaded-cache
-          key: downloaded-cache-${{ github.sha }}
-          restore-keys: |
-            downloaded-cache
-
-      - name: Download previous gems list
-        run: |
-          data=default_gems.json
-          mkdir -p .downloaded-cache
-          ln -s .downloaded-cache/$data .
-          curl -O -R -z ./$data https://stdgems.org/$data
-
-      - name: Make default gems list
-        run: |
-          require 'rubygems'
-          $:.unshift "lib"
-          rgver = File.foreach("lib/rubygems.rb") do |line|
-            break $1 if /^\s*VERSION\s*=\s*"([^"]+)"/ =~ line
-          end
-          gems = Dir.glob("{ext,lib}/**/*.gemspec").map do |f|
-            spec = Gem::Specification.load(f)
-            "#{spec.name} #{spec.version}"
-          end.sort
-          File.open("gems/default_gems", "w") do |f|
-            f.puts "RubyGems #{rgver}"
-            f.puts gems
-          end
-        shell: ruby --disable=gems {0}
-
-      - name: Maintain updated gems list in NEWS
-        run: |
-          require 'json'
-          news = File.read("NEWS.md")
-          prev = news[/since the \*+(\d+\.\d+\.\d+)\*+/, 1]
-          prevs = [prev, prev.sub(/\.\d+\z/, '')]
-          %W[default].each do |type|
-            last = JSON.parse(File.read("#{type}_gems.json"))['gems'].filter_map do |g|
-              v = g['versions'].values_at(*prevs).compact.first
-              g = g['gem']
-              g = 'RubyGems' if g == 'rubygems'
-              [g, v] if v
-            end.to_h
-            changed = File.foreach("gems/#{type}_gems").filter_map do |l|
-              next if l.start_with?("#")
-              g, v = l.split(" ", 3)
-              [g, v] unless last[g] == v
-            end
-            news.sub!(/^\*( +)The following #{type} gems? are updated\.\n\K(?: \1\* .*\n)*/) do
-              mark = "#{$1} * "
-              changed.map {|g, v|"#{mark}#{g} #{v}\n"}.join("")
-            end or next
-            File.write("NEWS.md", news)
-          end
-        shell: ruby {0}
-
-      - name: Check diffs
-        id: diff
-        run: |
-          git diff --color --no-ext-diff --ignore-submodules --exit-code NEWS.md
-        continue-on-error: true
-      - name: Commit
-        run: |
-          git pull --ff-only origin ${GITHUB_REF#refs/heads/}
-          git commit --message="Update default gems list at ${GITHUB_SHA:0:30} [ci skip]" NEWS.md
-          git push origin ${GITHUB_REF#refs/heads/}
-        env:
-          EMAIL: svn-admin@ruby-lang.org
-          GIT_AUTHOR_NAME: git
-          GIT_COMMITTER_NAME: git
-        if: ${{ github.repository == 'ruby/ruby' && !startsWith(github.event_name, 'pull') && steps.diff.outcome == 'failure' }}
diff --git a/.github/workflows/codeql-analysis.yml b/.github/workflows/codeql-analysis.yml
index 70fd22a7a0..8dba76fbe2 100644
--- a/.github/workflows/codeql-analysis.yml
+++ b/.github/workflows/codeql-analysis.yml
@@ -1,29 +1,42 @@
 name: "Code scanning - action"
 
 on:
-  push:
-    paths-ignore:
-      - 'doc/**'
-      - '**.md'
-      - '**.rdoc'
-  pull_request:
-    paths-ignore:
-      - 'doc/**'
-      - '**.md'
-      - '**.rdoc'
+  # push:
+  #   paths-ignore:
+  #     - 'doc/**'
+  #     - '**/man'
+  #     - '**.md'
+  #     - '**.rdoc'
+  #     - '**/.document'
+  # pull_request:
+  #   paths-ignore:
+  #     - 'doc/**'
+  #     - '**/man'
+  #     - '**.md'
+  #     - '**.rdoc'
+  #     - '**/.document'
   schedule:
-    - cron: '0 12 * * 4'
+    - cron: '0 12 * * *'
+  workflow_dispatch:
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
   cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
 
+permissions:  # added using https://github.com/step-security/secure-workflows
+  contents: read
+
 jobs:
   CodeQL-Build:
 
     # CodeQL runs on ubuntu-latest and windows-latest
+    permissions:
+      actions: read  # for github/codeql-action/init to get workflow details
+      contents: read  # for actions/checkout to fetch code
+      security-events: write  # for github/codeql-action/autobuild to send a status report
     runs-on: ubuntu-latest
-    if: ${{ !startsWith(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    # CodeQL fails to run pull requests from dependabot due to missing write access to upload results.
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') && github.event.head_commit.pusher.name != 'dependabot[bot]' }}
 
     env:
       enable_install_doc: no
@@ -36,9 +49,9 @@ jobs:
         sudo apt-get install --no-install-recommends -q -y build-essential libssl-dev libyaml-dev libreadline6-dev zlib1g-dev libncurses5-dev libffi-dev bison autoconf ruby
 
     - name: Checkout repository
-      uses: actions/checkout@v3
+      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
 
-    - uses: actions/cache@v3
+    - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
       with:
         path: .downloaded-cache
         key: downloaded-cache
@@ -47,15 +60,16 @@ jobs:
       run: sudo rm /usr/lib/ruby/vendor_ruby/rubygems/defaults/operating_system.rb
 
     - name: Initialize CodeQL
-      uses: github/codeql-action/init@v1
+      uses: github/codeql-action/init@959cbb7472c4d4ad70cdfe6f4976053fe48ab394 # v2.1.37
       with:
         config-file: ./.github/codeql/codeql-config.yml
+        trap-caching: false
 
     - name: Set ENV
       run: echo "GNUMAKEFLAGS=-j$((1 + $(nproc --all)))" >> $GITHUB_ENV
 
     - name: Autobuild
-      uses: github/codeql-action/autobuild@v1
+      uses: github/codeql-action/autobuild@959cbb7472c4d4ad70cdfe6f4976053fe48ab394 # v2.1.37
 
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@v1
+      uses: github/codeql-action/analyze@959cbb7472c4d4ad70cdfe6f4976053fe48ab394 # v2.1.37
diff --git a/.github/workflows/compilers.yml b/.github/workflows/compilers.yml
index 3bd299640d..caf12cc0f4 100644
--- a/.github/workflows/compilers.yml
+++ b/.github/workflows/compilers.yml
@@ -4,28 +4,36 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
+      - '**/.document'
   pull_request:
     paths-ignore:
       - 'doc/**'
-      - '**.md'
+      - '**/man'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
       - '**.rdoc'
+      - '**/.document'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
   cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
 
-# Github actions does not support YAML anchors.  This creative use of
+# GitHub actions does not support YAML anchors.  This creative use of
 # environment variables (plus the "echo $GITHUB_ENV" hack) is to reroute that
 # restriction.
 env:
   default_cc: clang-15
   append_cc: ''
-  crosshost: ''
 
   # -O1 is faster than -O3 in our tests... Majority of time are consumed trying
-  # to optimize binaries.  Also Github Actions run on relatively modern CPUs
+  # to optimize binaries.  Also GitHub Actions run on relatively modern CPUs
   # compared to, say, GCC 4 or Clang 3.  We don't specify `-march=native`
   # because compilers tend not understand what the CPU is.
   optflags: '-O1'
@@ -55,143 +63,160 @@ env:
     --color=always
     --tty=no
 
+permissions:
+  contents: read
+
 jobs:
   compile:
     strategy:
       fail-fast: false
       matrix:
+        env:
+          - {}
         entry:
-          - { key: default_cc, name: gcc-11,    value: gcc-11,    container: gcc-11 }
-          - { key: default_cc, name: gcc-10,    value: gcc-10,    container: gcc-10 }
-          - { key: default_cc, name: gcc-9,     value: gcc-9,     container: gcc-9 }
-          - { key: default_cc, name: gcc-8,     value: gcc-8,     container: gcc-8 }
-          - { key: default_cc, name: gcc-7,     value: gcc-7,     container: gcc-7 }
-          - { key: default_cc, name: gcc-6,     value: gcc-6,     container: gcc-6 }
-          - { key: default_cc, name: gcc-5,     value: gcc-5,     container: gcc-5 }
-          - { key: default_cc, name: gcc-4.8,   value: gcc-4.8,   container: gcc-4.8 }
-          - key: default_cc
-            name: 'gcc-11 LTO'
-            value: 'gcc-11 -O2 -flto=auto -ffat-lto-objects'
-            container: gcc-11
-            shared: '--disable-shared'
+          - { name: gcc-12,    env: { default_cc: gcc-12 } }
+          - { name: gcc-11,    env: { default_cc: gcc-11 } }
+          - { name: gcc-10,    env: { default_cc: gcc-10 } }
+          - { name: gcc-9,     env: { default_cc: gcc-9 } }
+          - { name: gcc-8,     env: { default_cc: gcc-8 } }
+          - { name: gcc-7,     env: { default_cc: gcc-7 } }
+          - name: 'gcc-13 LTO'
+            container: gcc-13
+            env:
+              default_cc: 'gcc-13 -flto=auto -ffat-lto-objects -Werror=lto-type-mismatch'
+              optflags: '-O2'
+            shared: disable
             # check: true
-          - { key: default_cc, name: clang-15,  value: clang-15,  container: clang-15 }
-          - { key: default_cc, name: clang-14,  value: clang-14,  container: clang-14 }
-          - { key: default_cc, name: clang-13,  value: clang-13,  container: clang-13 }
-          - { key: default_cc, name: clang-12,  value: clang-12,  container: clang-12 }
-          - { key: default_cc, name: clang-11,  value: clang-11,  container: clang-11 }
-          - { key: default_cc, name: clang-10,  value: clang-10,  container: clang-10 }
-          - { key: default_cc, name: clang-9,   value: clang-9,   container: clang-9 }
-          - { key: default_cc, name: clang-8,   value: clang-8,   container: clang-8 }
-          - { key: default_cc, name: clang-7,   value: clang-7,   container: clang-7 }
-          - { key: default_cc, name: clang-6.0, value: clang-6.0, container: clang-6.0 }
-          - { key: default_cc, name: clang-5.0, value: clang-5.0, container: clang-5.0 }
-          - { key: default_cc, name: clang-4.0, value: clang-4.0, container: clang-4.0 }
-          - { key: default_cc, name: clang-3.9, value: clang-3.9, container: clang-3.9 }
-          - key: default_cc
-            name: 'clang-14 LTO'
-            value: 'clang-14 -O2 -flto=auto'
-            container: clang-14
-            shared: '--disable-shared'
+          - { name: clang-16,  env: { default_cc: clang-16 } }
+          - { name: clang-15,  env: { default_cc: clang-15 } }
+          - { name: clang-14,  env: { default_cc: clang-14 } }
+          - { name: clang-13,  env: { default_cc: clang-13 } }
+          - { name: clang-12,  env: { default_cc: clang-12 } }
+          - { name: clang-11,  env: { default_cc: clang-11 } }
+          - { name: clang-10,  env: { default_cc: clang-10 } }
+          # llvm-objcopy<=9 doesn't have --wildcard. It compiles, but leaves Rust symbols in libyjit.o.
+          - { name: clang-9,   env: { default_cc: clang-9,   append_configure: '--disable-yjit' } }
+          - { name: clang-8,   env: { default_cc: clang-8,   append_configure: '--disable-yjit' } }
+          - { name: clang-7,   env: { default_cc: clang-7,   append_configure: '--disable-yjit' } }
+          - { name: clang-6.0, env: { default_cc: clang-6.0, append_configure: '--disable-yjit' } }
+          - name: 'clang-16 LTO'
+            container: clang-16
+            env:
+              default_cc: 'clang-16 -flto=auto'
+              optflags: '-O2'
+            shared: disable
             # check: true
 
-#         - { key: crosshost, name: aarch64-linux-gnu,     value: aarch64-linux-gnu, container: crossbuild-essential-arm64 }
-#         - { key: crosshost, name: arm-linux-gnueabi,     value: arm-linux-gnueabi }
-#         - { key: crosshost, name: arm-linux-gnueabihf,   value: arm-linux-gnueabihf }
-#         - { key: crosshost, name: i686-w64-mingw32,      value: i686-w64-mingw32 }
-#         - { key: crosshost, name: powerpc-linux-gnu,     value: powerpc-linux-gnu }
-#         - { key: crosshost, name: powerpc64le-linux-gnu, value: powerpc64le-linux-gnu, container: crossbuild-essential-ppc64el }
-#         - { key: crosshost, name: s390x-linux-gnu,       value: s390x-linux-gnu, container: crossbuild-essential-s390x }
-#         - { key: crosshost, name: x86_64-w64-mingw32,    value: x86_64-w64-mingw32, container: mingw-w64 }
-
-          - { key: append_cc, name: c99,   value: '-std=c99   -Werror=pedantic -pedantic-errors' }
-#         - { key: append_cc, name: c11,   value: '-std=c11   -Werror=pedantic -pedantic-errors' }
-#         - { key: append_cc, name: c17,   value: '-std=c17   -Werror=pedantic -pedantic-errors' }
-          - { key: append_cc, name: c2x,   value: '-std=c2x   -Werror=pedantic -pedantic-errors' }
-          - { key: CXXFLAGS,  name: c++98, value: '-std=c++98 -Werror=pedantic -pedantic-errors -Wno-c++11-long-long' }
-#         - { key: CXXFLAGS,  name: c++11, value: '-std=c++11 -Werror=pedantic -pedantic-errors -Wno-c++11-long-long' }
-#         - { key: CXXFLAGS,  name: c++14, value: '-std=c++14 -Werror=pedantic -pedantic-errors -Wno-c++11-long-long' }
-#         - { key: CXXFLAGS,  name: c++17, value: '-std=c++17 -Werror=pedantic -pedantic-errors -Wno-c++11-long-long' }
-          - { key: CXXFLAGS,  name: c++2a, value: '-std=c++2a -Werror=pedantic -pedantic-errors -Wno-c++11-long-long' }
-
-          - { key: optflags, name: '-O0', value: '-O0 -march=x86-64 -mtune=generic' }
-#         - { key: optflags, name: '-O3', value: '-O3 -march=x86-64 -mtune=generic', check: true }
-
-          - { key: append_configure, name: gmp,                  value: '--with-gmp' }
-          - { key: append_configure, name: jemalloc,             value: '--with-jemalloc' }
-          - { key: append_configure, name: valgrind,             value: '--with-valgrind' }
-          - { key: append_configure, name: 'coroutine=ucontext', value: '--with-coroutine=ucontext' }
-          - { key: append_configure, name: 'coroutine=pthread',  value: '--with-coroutine=pthread' }
-          - { key: append_configure, name: disable-jit-support,  value: '--disable-jit-support' }
-          - { key: append_configure, name: disable-dln,          value: '--disable-dln' }
-          - { key: append_configure, name: disable-rubygems,     value: '--disable-rubygems' }
-
-          - { key: cppflags, name: OPT_THREADED_CODE=1,            value: '-DOPT_THREADED_CODE=1' }
-          - { key: cppflags, name: OPT_THREADED_CODE=2,            value: '-DOPT_THREADED_CODE=2' }
-          - { key: cppflags, name: OPT_THREADED_CODE=3,            value: '-DOPT_THREADED_CODE=3' }
-
-          - { key: cppflags, name: NDEBUG,                         value: '-DNDEBUG' }
-          - { key: cppflags, name: RUBY_DEBUG,                     value: '-DRUBY_DEBUG' }
-#         - { key: cppflags, name: ARRAY_DEBUG,                    value: '-DARRAY_DEBUG' }
-#         - { key: cppflags, name: BIGNUM_DEBUG,                   value: '-DBIGNUM_DEBUG' }
-#         - { key: cppflags, name: CCAN_LIST_DEBUG,                value: '-DCCAN_LIST_DEBUG' }
-#         - { key: cppflags, name: CPDEBUG=-1,                     value: '-DCPDEBUG=-1' }
-#         - { key: cppflags, name: ENC_DEBUG,                      value: '-DENC_DEBUG' }
-#         - { key: cppflags, name: GC_DEBUG,                       value: '-DGC_DEBUG' }
-#         - { key: cppflags, name: HASH_DEBUG,                     value: '-DHASH_DEBUG' }
-#         - { key: cppflags, name: ID_TABLE_DEBUG,                 value: '-DID_TABLE_DEBUG' }
-#         - { key: cppflags, name: RGENGC_DEBUG=-1,                value: '-DRGENGC_DEBUG=-1' }
-#         - { key: cppflags, name: SYMBOL_DEBUG,                   value: '-DSYMBOL_DEBUG' }
-#         - { key: cppflags, name: THREAD_DEBUG=-1,                value: '-DTHREAD_DEBUG=-1' }
-
-#         - { key: cppflags, name: RGENGC_CHECK_MODE,              value: '-DRGENGC_CHECK_MODE' }
-#         - { key: cppflags, name: TRANSIENT_HEAP_CHECK_MODE,      value: '-DTRANSIENT_HEAP_CHECK_MODE' }
-#         - { key: cppflags, name: VM_CHECK_MODE,                  value: '-DVM_CHECK_MODE' }
-
-          - { key: cppflags, name: USE_EMBED_CI=0,                 value: '-DUSE_EMBED_CI=0' }
-          - { key: cppflags, name: USE_FLONUM=0,                   value: '-DUSE_FLONUM=0' }
-#         - { key: cppflags, name: USE_GC_MALLOC_OBJ_INFO_DETAILS, value: '-DUSE_GC_MALLOC_OBJ_INFO_DETAILS' }
-          - { key: cppflags, name: USE_LAZY_LOAD,                  value: '-DUSE_LAZY_LOAD' }
-#         - { key: cppflags, name: USE_RINCGC=0,                   value: '-DUSE_RINCGC=0' }
-#         - { key: cppflags, name: USE_SYMBOL_GC=0,                value: '-DUSE_SYMBOL_GC=0' }
-#         - { key: cppflags, name: USE_THREAD_CACHE=0,             value: '-DUSE_THREAD_CACHE=0' }
-#         - { key: cppflags, name: USE_TRANSIENT_HEAP=0,           value: '-DUSE_TRANSIENT_HEAP=0' }
-#         - { key: cppflags, name: USE_RUBY_DEBUG_LOG=1,           value: '-DUSE_RUBY_DEBUG_LOG=1' }
-          - { key: cppflags, name: USE_RVARGC=0,                   value: '-DUSE_RVARGC=0' }
-#         - { key: cppflags, name: USE_RVARGC=1,                   value: '-DUSE_RVARGC=1' }
-
-          - { key: cppflags, name: DEBUG_FIND_TIME_NUMGUESS,       value: '-DDEBUG_FIND_TIME_NUMGUESS' }
-          - { key: cppflags, name: DEBUG_INTEGER_PACK,             value: '-DDEBUG_INTEGER_PACK' }
-#         - { key: cppflags, name: ENABLE_PATH_CHECK,              value: '-DENABLE_PATH_CHECK' }
-
-          - { key: cppflags, name: GC_DEBUG_STRESS_TO_CLASS,       value: '-DGC_DEBUG_STRESS_TO_CLASS' }
-#         - { key: cppflags, name: GC_ENABLE_LAZY_SWEEP=0,         value: '-DGC_ENABLE_LAZY_SWEEP=0' }
-#         - { key: cppflags, name: GC_PROFILE_DETAIL_MEMOTY,       value: '-DGC_PROFILE_DETAIL_MEMOTY' }
-#         - { key: cppflags, name: GC_PROFILE_MORE_DETAIL,         value: '-DGC_PROFILE_MORE_DETAIL' }
-
-#         - { key: cppflags, name: CALC_EXACT_MALLOC_SIZE,         value: '-DCALC_EXACT_MALLOC_SIZE' }
-#         - { key: cppflags, name: MALLOC_ALLOCATED_SIZE_CHECK,    value: '-DMALLOC_ALLOCATED_SIZE_CHECK' }
-
-#         - { key: cppflags, name: IBF_ISEQ_ENABLE_LOCAL_BUFFER,   value: '-DIBF_ISEQ_ENABLE_LOCAL_BUFFER' }
-
-#         - { key: cppflags, name: RGENGC_ESTIMATE_OLDMALLOC,      value: '-DRGENGC_ESTIMATE_OLDMALLOC' }
-#         - { key: cppflags, name: RGENGC_FORCE_MAJOR_GC,          value: '-DRGENGC_FORCE_MAJOR_GC' }
-#         - { key: cppflags, name: RGENGC_OBJ_INFO,                value: '-DRGENGC_OBJ_INFO' }
-#         - { key: cppflags, name: RGENGC_OLD_NEWOBJ_CHECK,        value: '-DRGENGC_OLD_NEWOBJ_CHECK' }
-#         - { key: cppflags, name: RGENGC_PROFILE,                 value: '-DRGENGC_PROFILE' }
-
-#         - { key: cppflags, name: VM_DEBUG_BP_CHECK,              value: '-DVM_DEBUG_BP_CHECK' }
-#         - { key: cppflags, name: VM_DEBUG_VERIFY_METHOD_CACHE,   value: '-DVM_DEBUG_VERIFY_METHOD_CACHE' }
-
-          - { key: cppflags, name: MJIT_FORCE_ENABLE,              value: '-DMJIT_FORCE_ENABLE' }
-          - { key: cppflags, name: YJIT_FORCE_ENABLE,              value: '-DYJIT_FORCE_ENABLE' }
+#         - { name: aarch64-linux-gnu,     crosshost: aarch64-linux-gnu, container: crossbuild-essential-arm64 }
+#         - { name: arm-linux-gnueabi,     crosshost: arm-linux-gnueabi }
+#         - { name: arm-linux-gnueabihf,   crosshost: arm-linux-gnueabihf }
+#         - { name: i686-w64-mingw32,      crosshost: i686-w64-mingw32 }
+#         - { name: powerpc-linux-gnu,     crosshost: powerpc-linux-gnu }
+#         - { name: powerpc64le-linux-gnu, crosshost: powerpc64le-linux-gnu, container: crossbuild-essential-ppc64el }
+#         - { name: s390x-linux-gnu,       crosshost: s390x-linux-gnu, container: crossbuild-essential-s390x }
+#         - { name: x86_64-w64-mingw32,    crosshost: x86_64-w64-mingw32, container: mingw-w64 }
+
+          # -Wno-strict-prototypes is necessary with current clang-15 since
+          # older autoconf generate functions without prototype and -pedantic
+          # now implies strict-prototypes. Disabling the error but leaving the
+          # warning generates a lot of noise from use of ANYARGS in
+          # rb_define_method() and friends.
+          # See: https://github.com/llvm/llvm-project/commit/11da1b53d8cd3507959022cd790d5a7ad4573d94
+          - { name: c99,   env: { append_cc: '-std=c99   -Werror=pedantic -pedantic-errors -Wno-strict-prototypes' } }
+#         - { name: c11,   env: { append_cc: '-std=c11   -Werror=pedantic -pedantic-errors -Wno-strict-prototypes' } }
+#         - { name: c17,   env: { append_cc: '-std=c17   -Werror=pedantic -pedantic-errors -Wno-strict-prototypes' } }
+          - { name: c2x,   env: { append_cc: '-std=c2x   -Werror=pedantic -pedantic-errors -Wno-strict-prototypes' } }
+          - { name: c++98, env: { CXXFLAGS: '-std=c++98 -Werror=pedantic -pedantic-errors -Wno-c++11-long-long' } }
+#         - { name: c++11, env: { CXXFLAGS: '-std=c++11 -Werror=pedantic -pedantic-errors -Wno-c++11-long-long' } }
+#         - { name: c++14, env: { CXXFLAGS: '-std=c++14 -Werror=pedantic -pedantic-errors -Wno-c++11-long-long' } }
+#         - { name: c++17, env: { CXXFLAGS: '-std=c++17 -Werror=pedantic -pedantic-errors -Wno-c++11-long-long' } }
+          - { name: c++2a, env: { CXXFLAGS: '-std=c++2a -Werror=pedantic -pedantic-errors -Wno-c++11-long-long' } }
+
+          - { name: '-O0', env: { optflags: '-O0 -march=x86-64 -mtune=generic' } }
+#         - { name: '-O3', env: { optflags: '-O3 -march=x86-64 -mtune=generic' }, check: true }
+
+          - { name: gmp,                  env: { append_configure: '--with-gmp' } }
+          - { name: jemalloc,             env: { append_configure: '--with-jemalloc' } }
+          - { name: valgrind,             env: { append_configure: '--with-valgrind' } }
+          - { name: 'coroutine=ucontext', env: { append_configure: '--with-coroutine=ucontext' } }
+          - { name: 'coroutine=pthread',  env: { append_configure: '--with-coroutine=pthread' } }
+          - { name: disable-jit-support,  env: { append_configure: '--disable-jit-support' } }
+          - { name: disable-dln,          env: { append_configure: '--disable-dln' } }
+          - { name: enable-mkmf-verbose,  env: { append_configure: '--enable-mkmf-verbose' } }
+          - { name: disable-rubygems,     env: { append_configure: '--disable-rubygems' } }
+          - { name: RUBY_DEVEL,           env: { append_configure: '--enable-devel' } }
+
+          - { name: OPT_THREADED_CODE=1,            env: { cppflags: '-DOPT_THREADED_CODE=1' } }
+          - { name: OPT_THREADED_CODE=2,            env: { cppflags: '-DOPT_THREADED_CODE=2' } }
+          - { name: OPT_THREADED_CODE=3,            env: { cppflags: '-DOPT_THREADED_CODE=3' } }
+
+          - { name: NDEBUG,                         env: { cppflags: '-DNDEBUG' } }
+          - { name: RUBY_DEBUG,                     env: { cppflags: '-DRUBY_DEBUG' } }
+#         - { name: ARRAY_DEBUG,                    env: { cppflags: '-DARRAY_DEBUG' } }
+#         - { name: BIGNUM_DEBUG,                   env: { cppflags: '-DBIGNUM_DEBUG' } }
+#         - { name: CCAN_LIST_DEBUG,                env: { cppflags: '-DCCAN_LIST_DEBUG' } }
+#         - { name: CPDEBUG=-1,                     env: { cppflags: '-DCPDEBUG=-1' } }
+#         - { name: ENC_DEBUG,                      env: { cppflags: '-DENC_DEBUG' } }
+#         - { name: GC_DEBUG,                       env: { cppflags: '-DGC_DEBUG' } }
+#         - { name: HASH_DEBUG,                     env: { cppflags: '-DHASH_DEBUG' } }
+#         - { name: ID_TABLE_DEBUG,                 env: { cppflags: '-DID_TABLE_DEBUG' } }
+#         - { name: RGENGC_DEBUG=-1,                env: { cppflags: '-DRGENGC_DEBUG=-1' } }
+#         - { name: SYMBOL_DEBUG,                   env: { cppflags: '-DSYMBOL_DEBUG' } }
+
+#         - { name: RGENGC_CHECK_MODE,              env: { cppflags: '-DRGENGC_CHECK_MODE' } }
+#         - { name: TRANSIENT_HEAP_CHECK_MODE,      env: { cppflags: '-DTRANSIENT_HEAP_CHECK_MODE' } }
+#         - { name: VM_CHECK_MODE,                  env: { cppflags: '-DVM_CHECK_MODE' } }
+
+          - { name: USE_EMBED_CI=0,                 env: { cppflags: '-DUSE_EMBED_CI=0' } }
+          - name: USE_FLONUM=0,
+            env:
+              cppflags: '-DUSE_FLONUM=0'
+              # yjit requires FLONUM for the pointer tagging scheme
+              append_configure: '--disable-yjit'
+#         - { name: USE_GC_MALLOC_OBJ_INFO_DETAILS, env: { cppflags: '-DUSE_GC_MALLOC_OBJ_INFO_DETAILS' } }
+          - { name: USE_LAZY_LOAD,                  env: { cppflags: '-DUSE_LAZY_LOAD' } }
+#         - { name: USE_RINCGC=0,                   env: { cppflags: '-DUSE_RINCGC=0' } }
+#         - { name: USE_SYMBOL_GC=0,                env: { cppflags: '-DUSE_SYMBOL_GC=0' } }
+#         - { name: USE_THREAD_CACHE=0,             env: { cppflags: '-DUSE_THREAD_CACHE=0' } }
+#         - { name: USE_TRANSIENT_HEAP=0,           env: { cppflags: '-DUSE_TRANSIENT_HEAP=0' } }
+#         - { name: USE_RUBY_DEBUG_LOG=1,           env: { cppflags: '-DUSE_RUBY_DEBUG_LOG=1' } }
+          - { name: USE_RVARGC=0,                   env: { cppflags: '-DUSE_RVARGC=0' } }
+#         - { name: USE_RVARGC=1,                   env: { cppflags: '-DUSE_RVARGC=1' } }
+#         - { name: USE_DEBUG_COUNTER,              env: { cppflags: '-DUSE_DEBUG_COUNTER=1', RUBY_DEBUG_COUNTER_DISABLE: '1' } }
+
+          - { name: DEBUG_FIND_TIME_NUMGUESS,       env: { cppflags: '-DDEBUG_FIND_TIME_NUMGUESS' } }
+          - { name: DEBUG_INTEGER_PACK,             env: { cppflags: '-DDEBUG_INTEGER_PACK' } }
+#         - { name: ENABLE_PATH_CHECK,              env: { cppflags: '-DENABLE_PATH_CHECK' } }
+
+          - { name: GC_DEBUG_STRESS_TO_CLASS,       env: { cppflags: '-DGC_DEBUG_STRESS_TO_CLASS' } }
+#         - { name: GC_ENABLE_LAZY_SWEEP=0,         env: { cppflags: '-DGC_ENABLE_LAZY_SWEEP=0' } }
+#         - { name: GC_PROFILE_DETAIL_MEMOTY,       env: { cppflags: '-DGC_PROFILE_DETAIL_MEMOTY' } }
+#         - { name: GC_PROFILE_MORE_DETAIL,         env: { cppflags: '-DGC_PROFILE_MORE_DETAIL' } }
+
+#         - { name: CALC_EXACT_MALLOC_SIZE,         env: { cppflags: '-DCALC_EXACT_MALLOC_SIZE' } }
+#         - { name: MALLOC_ALLOCATED_SIZE_CHECK,    env: { cppflags: '-DMALLOC_ALLOCATED_SIZE_CHECK' } }
+
+#         - { name: IBF_ISEQ_ENABLE_LOCAL_BUFFER,   env: { cppflags: '-DIBF_ISEQ_ENABLE_LOCAL_BUFFER' } }
+
+#         - { name: RGENGC_ESTIMATE_OLDMALLOC,      env: { cppflags: '-DRGENGC_ESTIMATE_OLDMALLOC' } }
+#         - { name: RGENGC_FORCE_MAJOR_GC,          env: { cppflags: '-DRGENGC_FORCE_MAJOR_GC' } }
+#         - { name: RGENGC_OBJ_INFO,                env: { cppflags: '-DRGENGC_OBJ_INFO' } }
+#         - { name: RGENGC_OLD_NEWOBJ_CHECK,        env: { cppflags: '-DRGENGC_OLD_NEWOBJ_CHECK' } }
+#         - { name: RGENGC_PROFILE,                 env: { cppflags: '-DRGENGC_PROFILE' } }
+
+#         - { name: VM_DEBUG_BP_CHECK,              env: { cppflags: '-DVM_DEBUG_BP_CHECK' } }
+#         - { name: VM_DEBUG_VERIFY_METHOD_CACHE,   env: { cppflags: '-DVM_DEBUG_VERIFY_METHOD_CACHE' } }
+
+          - { name: MJIT_FORCE_ENABLE,              env: { cppflags: '-DMJIT_FORCE_ENABLE' } }
+          - { name: YJIT_FORCE_ENABLE,              env: { cppflags: '-DYJIT_FORCE_ENABLE' } }
 
     name: ${{ matrix.entry.name }}
     runs-on: ubuntu-latest
     container:
-      image: ghcr.io/ruby/ruby-ci-image:${{ matrix.entry.container || 'clang-15' }}
+      image: ghcr.io/ruby/ruby-ci-image:${{ matrix.entry.container || matrix.entry.env.default_cc || 'clang-15' }}
       options: --user root
-    if: ${{ !startsWith(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    env: ${{ matrix.entry.env || matrix.env }}
     steps:
       - run: id
         working-directory:
@@ -199,12 +224,11 @@ jobs:
         working-directory:
       - name: setenv
         run: |
-          echo "${{ matrix.entry.key }}=${{ matrix.entry.value }}" >> $GITHUB_ENV
           echo "GNUMAKEFLAGS=-sj$((1 + $(nproc --all)))" >> $GITHUB_ENV
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           path: src
-      - uses: actions/cache@v3
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: src/.downloaded-cache
           key: downloaded-cache
@@ -213,25 +237,32 @@ jobs:
       - name: Run configure
         run: >
           ../src/configure -C ${default_configure} ${append_configure}
-          ${{ matrix.entry.key == 'crosshost' && '--host="${crosshost}"' || '--with-gcc="${default_cc} ${append_cc}"' }}
-          ${{ matrix.entry.shared || '--enable-shared' }}
+          --${{
+            matrix.entry.crosshost && 'host' || 'with-gcc'
+          }}=${{
+            matrix.entry.crosshost || '"${default_cc}${append_cc:+ $append_cc}"'
+          }}
+          --${{ matrix.entry.shared || 'enable' }}-shared
       - run: make extract-extlibs
       - run: make incs
+      - run: make showflags
       - run: make
       - run: make leaked-globals
       - run: make test
       - run: make install
         if: ${{ matrix.entry.check }}
-      - run: make prepare-gems
-        if: ${{ matrix.entry.check }}
       - run: make test-tool
         if: ${{ matrix.entry.check }}
       - run: make test-all TESTS='-- ruby -ext-'
         if: ${{ matrix.entry.check }}
       - run: make test-spec
+        env:
+          CHECK_LEAKS: true
         if: ${{ matrix.entry.check }}
+      - run: make test-annocheck
+        if: ${{ matrix.entry.check && endsWith(matrix.entry.name, 'annocheck') }}
 
-      - uses: k0kubun/action-slack@v2.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
@@ -239,7 +270,7 @@ jobs:
               "env": "${{ github.workflow }} / ${{ matrix.entry.name }}",
               "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
               "commit": "${{ github.sha }}",
-              "branch": "${{ github.ref }}".split('/').reverse()[0]
+              "branch": "${{ github.ref_name }}"
             }
         env:
           SLACK_WEBHOOK_URL: ${{ secrets.SIMPLER_ALERTS_URL }} # ruby-lang slack: ruby/simpler-alerts-bot
diff --git a/.github/workflows/macos.yml b/.github/workflows/macos.yml
new file mode 100644
index 0000000000..d8dc58b119
--- /dev/null
+++ b/.github/workflows/macos.yml
@@ -0,0 +1,113 @@
+name: macOS
+on:
+  push:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  pull_request:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+
+concurrency:
+  group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
+  cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
+
+permissions:
+  contents: read
+
+jobs:
+  make:
+    strategy:
+      matrix:
+        test_task: ["check"] # "test-bundler-parallel", "test-bundled-gems"
+        os:
+          - macos-13
+          - macos-14
+          - macos-15
+      fail-fast: false
+    env:
+      GITPULLOPTIONS: --no-tags origin ${{github.ref}}
+    runs-on: ${{ matrix.os }}
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    steps:
+      - run: mkdir build
+        working-directory:
+      - name: git config
+        run: |
+          git config --global advice.detachedHead 0
+          git config --global init.defaultBranch garbage
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          path: src
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        with:
+          path: src/.downloaded-cache
+          key: downloaded-cache
+      - name: Install libraries
+        run: |
+          brew install gmp libffi openssl@1.1 zlib autoconf automake libtool readline bison
+        working-directory: src
+      - name: Set ENV
+        run: |
+          echo "MAKEFLAGS=-j$((1 + $(sysctl -n hw.activecpu)))" >> $GITHUB_ENV
+          echo "PATH="/usr/local/opt/bison/bin:/opt/homebrew/opt/bison/bin:$PATH"" >> $GITHUB_ENV
+      - run: ./autogen.sh
+        working-directory: src
+      - name: Run configure
+        run: ../src/configure -C --disable-install-doc --with-openssl-dir=$(brew --prefix openssl@1.1) --with-readline-dir=$(brew --prefix readline)
+      - run: make incs
+      - run: make prepare-gems
+        if: ${{ matrix.test_task == 'test-bundled-gems' }}
+      - run: make
+      - run: make leaked-globals
+        if: ${{ matrix.test_task == 'check' }}
+      - name: make ${{ matrix.test_task }}
+        run: |
+          make -s ${{ matrix.test_task }} ${TESTS:+TESTS=`echo "$TESTS" | sed 's| |$$/ -n!/|g;s|^|-n!/|;s|$|$$/|'`}
+        timeout-minutes: 40
+        env:
+          RUBY_TESTOPTS: "-q --tty=no"
+          TESTS: ${{ matrix.test_task == 'check' && matrix.skipped_tests || '' }}
+          TEST_BUNDLED_GEMS_ALLOW_FAILURES: ""
+          PRECHECK_BUNDLED_GEMS: "no"
+      - name: make skipped tests
+        run: |
+          make -s test-all TESTS=`echo "$TESTS" | sed 's| |$$/ -n/|g;s|^|-n/|;s|$|$$/|'`
+        env:
+          GNUMAKEFLAGS: ""
+          RUBY_TESTOPTS: "-v --tty=no"
+          TESTS: ${{ matrix.skipped_tests }}
+          PRECHECK_BUNDLED_GEMS: "no"
+        if: ${{ matrix.test_task == 'check' && matrix.skipped_tests != '' }}
+        continue-on-error: ${{ matrix.continue-on-skipped_tests || false }}
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
+        with:
+          payload: |
+            {
+              "ci": "GitHub Actions",
+              "env": "${{ matrix.os }} / ${{ matrix.test_task }}${{ matrix.configure }}",
+              "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
+              "commit": "${{ github.sha }}",
+              "branch": "${{ github.ref_name }}"
+            }
+        env:
+          SLACK_WEBHOOK_URL: ${{ secrets.SIMPLER_ALERTS_URL }} # ruby-lang slack: ruby/simpler-alerts-bot
+        if: ${{ failure() && github.event_name == 'push' }}
+
+defaults:
+  run:
+    working-directory: build
diff --git a/.github/workflows/mingw.yml b/.github/workflows/mingw.yml
index 8e3aec6e6f..0df917d3d8 100644
--- a/.github/workflows/mingw.yml
+++ b/.github/workflows/mingw.yml
@@ -3,18 +3,32 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
+      - '**/.document'
   pull_request:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
   cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
 
+permissions:
+  contents: read
+
 # Notes:
 # Actions console encoding causes issues, see test-all & test-spec steps
 #
@@ -26,23 +40,22 @@ jobs:
       MSYSTEM: ${{ matrix.msystem }}
       MSYS2_ARCH: x86_64
       CHOST: "x86_64-w64-mingw32"
-      CFLAGS:   "-march=x86-64 -mtune=generic -O3 -pipe -fstack-protector-strong"
+      CFLAGS:   "-march=x86-64 -mtune=generic -O3 -pipe"
       CXXFLAGS: "-march=x86-64 -mtune=generic -O3 -pipe"
       CPPFLAGS: "-D_FORTIFY_SOURCE=2 -D__USE_MINGW_ANSI_STDIO=1 -DFD_SETSIZE=2048"
-      LDFLAGS:  "-pipe -fstack-protector-strong"
+      LDFLAGS:  "-pipe"
       UPDATE_UNICODE: "UNICODE_FILES=. UNICODE_PROPERTY_FILES=. UNICODE_AUXILIARY_FILES=. UNICODE_EMOJI_FILES=."
       GITPULLOPTIONS: --no-tags origin ${{github.ref}}
     strategy:
       matrix:
         include:
-          - msystem: "MINGW64"
-            base_ruby: 2.6
-            test_task: "check" # to make job names consistent
+          # To mitigate flakiness of MinGW CI, we test only one runtime that newer MSYS2 uses.
           - msystem: "UCRT64"
             base_ruby: head
-            test_task: "check" # to make job names consistent
+            test_task: "check"
+            test-all-opts: "--name=!/TestObjSpace#test_reachable_objects_during_iteration/"
       fail-fast: false
-    if: ${{ !startsWith(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
     steps:
       - run: mkdir build
         working-directory:
@@ -52,21 +65,20 @@ jobs:
           git config --global core.eol lf
           git config --global advice.detachedHead 0
           git config --global init.defaultBranch garbage
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           path: src
-      - uses: actions/cache@v3
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: src/.downloaded-cache
           key: downloaded-cache
       - name: Set up Ruby & MSYS2
-        uses: ruby/setup-ruby@v1
+        uses: ruby/setup-ruby@13e7a03dc3ac6c3798f4570bfead2aed4d96abfb # v1.244.0
         with:
           ruby-version: ${{ matrix.base_ruby }}
       - name: set env
         run: |
           echo "GNUMAKEFLAGS=-j$((2 * NUMBER_OF_PROCESSORS))" >> $GITHUB_ENV
-          echo "TEST_JOBS=$((15 * NUMBER_OF_PROCESSORS / 10))" >> $GITHUB_ENV
 
       - name: where check
         run: |
@@ -112,7 +124,7 @@ jobs:
           make update-gems
 
       - name: make all
-        timeout-minutes: 20
+        timeout-minutes: 30
         run: |
           make
 
@@ -126,23 +138,28 @@ jobs:
         timeout-minutes: 5
         run: |
           make test
+        if: ${{matrix.test_task == 'check' || matrix.test_task == 'test'}}
 
       - name: test-all
         timeout-minutes: 45
         run: |
           # Actions uses UTF8, causes test failures, similar to normal OS setup
           chcp.com 437
-          make test-all
+          make ${{ StartsWith(matrix.test_task, 'test/') && matrix.test_task || 'test-all' }}
         env:
-          RUBY_TESTOPTS: -j${{env.TEST_JOBS}} --retry --job-status=normal --show-skip --timeout-scale=1.5
+          RUBY_TESTOPTS: >-
+            --retry --job-status=normal --show-skip --timeout-scale=1.5
+            ${{ matrix.test-all-opts }}
           BUNDLER_VERSION:
+        if: ${{matrix.test_task == 'check' || matrix.test_task == 'test-all' || StartsWith(matrix.test_task, 'test/')}}
 
       - name: test-spec
         timeout-minutes: 10
         run: |
-          make test-spec
+          make ${{ StartsWith(matrix.test_task, 'spec/') && matrix.test_task || 'test-spec' }}
+        if: ${{matrix.test_task == 'check' || matrix.test_task == 'test-spec' || StartsWith(matrix.test_task, 'spec/')}}
 
-      - uses: k0kubun/action-slack@v2.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
@@ -150,7 +167,7 @@ jobs:
               "env": "${{ github.workflow }} ${{ matrix.msystem }} / ${{ matrix.test_task }}",
               "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
               "commit": "${{ github.sha }}",
-              "branch": "${{ github.ref }}".split('/').reverse()[0]
+              "branch": "${{ github.ref_name }}"
             }
         env:
           SLACK_WEBHOOK_URL: ${{ secrets.SIMPLER_ALERTS_URL }} # ruby-lang slack: ruby/simpler-alerts-bot
diff --git a/.github/workflows/mjit-bindgen.yml b/.github/workflows/mjit-bindgen.yml
new file mode 100644
index 0000000000..26f8a1b2aa
--- /dev/null
+++ b/.github/workflows/mjit-bindgen.yml
@@ -0,0 +1,104 @@
+name: MJIT bindgen
+on:
+  push:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  pull_request:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+
+concurrency:
+  group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
+  cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
+
+permissions:
+  contents: read
+
+jobs:
+  make:
+    strategy:
+      matrix:
+        include:
+          - task: mjit-bindgen
+      fail-fast: false
+    runs-on: ubuntu-22.04
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    steps:
+      - run: mkdir build
+        working-directory:
+      - name: Set ENV
+        run: |
+          echo "GNUMAKEFLAGS=-j$((1 + $(nproc --all)))" >> $GITHUB_ENV
+      - name: Install libraries
+        run: |
+          set -x
+          sudo apt-get update -q || :
+          sudo apt-get install --no-install-recommends -q -y \
+          build-essential \
+          libssl-dev libyaml-dev libreadline6-dev \
+          zlib1g-dev libncurses5-dev libffi-dev \
+          libclang1-14 \
+          bison autoconf
+          sudo apt-get install -q -y pkg-config || :
+      - name: Set up Ruby
+        uses: ruby/setup-ruby@13e7a03dc3ac6c3798f4570bfead2aed4d96abfb # v1.244.0
+        with:
+          ruby-version: '3.1'
+      - name: git config
+        run: |
+          git config --global advice.detachedHead 0
+          git config --global init.defaultBranch garbage
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          path: src
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        with:
+          path: src/.downloaded-cache
+          key: downloaded-cache
+      - name: Fixed world writable dirs
+        run: |
+          chmod -v go-w $HOME $HOME/.config
+          sudo chmod -R go-w /usr/share
+          sudo bash -c 'IFS=:; for d in '"$PATH"'; do chmod -v go-w $d; done' || :
+      - run: ./autogen.sh
+        working-directory: src
+      - name: Run configure
+        run: ../src/configure -C --disable-install-doc --prefix=$(pwd)/install --enable-yjit=dev_nodebug
+      - run: make incs
+      - run: make
+      - run: make install
+      - run: make ${{ matrix.task }}
+      - run: git diff --exit-code
+        working-directory: src
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
+        with:
+          payload: |
+            {
+              "ci": "GitHub Actions",
+              "env": "${{ matrix.os }} / ${{ matrix.test_task }}${{ matrix.configure }}",
+              "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
+              "commit": "${{ github.sha }}",
+              "branch": "${{ github.ref_name }}"
+            }
+        env:
+          SLACK_WEBHOOK_URL: ${{ secrets.SIMPLER_ALERTS_URL }} # ruby-lang slack: ruby/simpler-alerts-bot
+        if: ${{ failure() && github.event_name == 'push' }}
+
+defaults:
+  run:
+    working-directory: build
diff --git a/.github/workflows/mjit.yml b/.github/workflows/mjit.yml
index d5d9cecc56..6f7181489a 100644
--- a/.github/workflows/mjit.yml
+++ b/.github/workflows/mjit.yml
@@ -3,30 +3,47 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
+      - '**/.document'
   pull_request:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
+      - '**/.document'
+      - '**.[1-8]'
+      - '**.ronn'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+      - '**.[1-8]'
+      - '**.ronn'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
   cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
 
+permissions:
+  contents: read
+
 jobs:
   make:
     strategy:
       matrix:
-        test_task: [ "check" ] # to make job names consistent
-        jit_opts: [ "--mjit", "--mjit-wait" ]
+        test_task: [check] # to make job names consistent
+        mjit_opts: [--mjit-wait]
       fail-fast: false
     runs-on: ubuntu-latest
-    if: ${{ !startsWith(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
     env:
       TESTOPTS: '-q --tty=no'
-      RUN_OPTS: '--disable-gems ${{ matrix.jit_opts }} --mjit-debug=-ggdb3'
+      RUN_OPTS: '--disable-gems ${{ matrix.mjit_opts }} --mjit-debug=-ggdb3'
       GITPULLOPTIONS: --no-tags origin ${{github.ref}}
     steps:
       - run: mkdir build
@@ -40,10 +57,10 @@ jobs:
         run: |
           git config --global advice.detachedHead 0
           git config --global init.defaultBranch garbage
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           path: src
-      - uses: actions/cache@v3
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: src/.downloaded-cache
           key: downloaded-cache
@@ -62,31 +79,30 @@ jobs:
       - run: make incs
       - run: make
       - run: sudo make -s install
-      - run: sudo apt-get install gdb # used by test / test-all failure
       - name: Run test
         run: |
-          ulimit -c unlimited
+          unset GNUMAKEFLAGS
           make -s test RUN_OPTS="$RUN_OPTS"
         timeout-minutes: 60
-      - name: Run test-all
-        run: |
-          ulimit -c unlimited
-          make -s test-all RUN_OPTS="$RUN_OPTS"
-        timeout-minutes: 60
+      # - name: Run test-all
+      #   run: |
+      #     ulimit -c unlimited
+      #     make -s test-all RUN_OPTS="$RUN_OPTS"
+      #   timeout-minutes: 60
       - name: Run test-spec
         run: |
-          ulimit -c unlimited
+          unset GNUMAKEFLAGS
           make -s test-spec RUN_OPTS="$RUN_OPTS"
         timeout-minutes: 60
-      - uses: k0kubun/action-slack@v2.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
               "ci": "GitHub Actions",
-              "env": "${{ github.workflow }} / ${{ matrix.test_task }} ${{ matrix.jit_opts }}",
+              "env": "${{ github.workflow }} / ${{ matrix.test_task }} ${{ matrix.mjit_opts }}",
               "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
               "commit": "${{ github.sha }}",
-              "branch": "${{ github.ref }}".split('/').reverse()[0]
+              "branch": "${{ github.ref_name }}"
             }
         env:
           SLACK_WEBHOOK_URL: ${{ secrets.SIMPLER_ALERTS_URL }} # ruby-lang slack: ruby/simpler-alerts-bot
diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
new file mode 100644
index 0000000000..5d4474d978
--- /dev/null
+++ b/.github/workflows/publish.yml
@@ -0,0 +1,18 @@
+name: Start release workflow
+on:
+  push:
+    tags:
+      - '*'
+
+jobs:
+  notify:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Build release package
+        run: |
+          curl -L -X POST \
+            -H "Authorization: Bearer ${{ secrets.MATZBOT_GITHUB_WORKFLOW_TOKEN }}" \
+            -H "Accept: application/vnd.github+json" \
+            -H "X-GitHub-Api-Version: 2022-11-28" \
+            https://api.github.com/repos/ruby/actions/dispatches \
+            -d '{"event_type": "${{ github.ref }}"}'
diff --git a/.github/workflows/scorecards.yml b/.github/workflows/scorecards.yml
new file mode 100644
index 0000000000..c12a95362d
--- /dev/null
+++ b/.github/workflows/scorecards.yml
@@ -0,0 +1,72 @@
+# This workflow uses actions that are not certified by GitHub. They are provided
+# by a third-party and are governed by separate terms of service, privacy
+# policy, and support documentation.
+
+name: Scorecards supply-chain security
+on:
+  # For Branch-Protection check. Only the default branch is supported. See
+  # https://github.com/ossf/scorecard/blob/main/docs/checks.md#branch-protection
+  branch_protection_rule:
+  # To guarantee Maintained check is occasionally updated. See
+  # https://github.com/ossf/scorecard/blob/main/docs/checks.md#maintained
+  schedule:
+    - cron: '22 4 * * 2'
+  push:
+    branches: [ "master" ]
+
+# Declare default permissions as read only.
+permissions: read-all
+
+jobs:
+  analysis:
+    name: Scorecards analysis
+    runs-on: ubuntu-latest
+    permissions:
+      # Needed to upload the results to code-scanning dashboard.
+      security-events: write
+      # Needed to publish results and get a badge (see publish_results below).
+      id-token: write
+      # Uncomment the permissions below if installing in a private repository.
+      # contents: read
+      # actions: read
+
+    steps:
+      - name: "Checkout code"
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          persist-credentials: false
+
+      - name: "Run analysis"
+        uses: ossf/scorecard-action@ea651e62978af7915d09fe2e282747c798bf2dab # v2.4.1
+        with:
+          results_file: results.sarif
+          results_format: sarif
+          # (Optional) Read-only PAT token. Uncomment the `repo_token` line below if:
+          # - you want to enable the Branch-Protection check on a *public* repository, or
+          # - you are installing Scorecards on a *private* repository
+          # To create the PAT, follow the steps in https://github.com/ossf/scorecard-action#authentication-with-pat.
+          repo_token: ${{ secrets.SCORECARD_READ_TOKEN }}
+
+          # Public repositories:
+          #   - Publish results to OpenSSF REST API for easy access by consumers
+          #   - Allows the repository to include the Scorecard badge.
+          #   - See https://github.com/ossf/scorecard-action#publishing-results.
+          # For private repositories:
+          #   - `publish_results` will always be set to `false`, regardless
+          #     of the value entered here.
+          publish_results: true
+
+      # Upload the results as artifacts (optional). Commenting out will disable uploads of run results in SARIF
+      # format to the repository Actions tab.
+      - name: "Upload artifact"
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
+        with:
+          name: SARIF file
+          path: results.sarif
+          retention-days: 5
+
+      # Upload the results to GitHub's code scanning dashboard.
+      - name: "Upload to code-scanning"
+        uses: github/codeql-action/upload-sarif@959cbb7472c4d4ad70cdfe6f4976053fe48ab394 # v2.1.27
+        with:
+          sarif_file: results.sarif
diff --git a/.github/workflows/spec_guards.yml b/.github/workflows/spec_guards.yml
index 18e2d3c1a8..4521195a2b 100644
--- a/.github/workflows/spec_guards.yml
+++ b/.github/workflows/spec_guards.yml
@@ -2,43 +2,61 @@ name: Rubyspec Version Guards Check
 
 on:
   push:
-    paths-ignore:
-      - 'doc/**'
-      - '**.md'
-      - '**.rdoc'
+    paths:
+      - 'spec/**'
+      - '!spec/*.md'
   pull_request:
-    paths-ignore:
-      - 'doc/**'
-      - '**.md'
-      - '**.rdoc'
+    paths:
+      - 'spec/**'
+      - '!spec/*.md'
+  merge_group:
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
   cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
 
+permissions:
+  contents: read
+
 jobs:
   rubyspec:
     name: Rubyspec
-    runs-on: ubuntu-20.04
-    if: ${{ !startsWith(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+
+    runs-on: ubuntu-22.04
+
+    if: >-
+      ${{!(false
+      || contains(github.event.head_commit.message, '[DOC]')
+      || contains(github.event.head_commit.message, 'Document')
+      || contains(github.event.pull_request.title, '[DOC]')
+      || contains(github.event.pull_request.title, 'Document')
+      || contains(github.event.pull_request.labels.*.name, 'Document')
+      || (github.event_name == 'push' && github.actor == 'dependabot[bot]')
+      )}}
+
     strategy:
       matrix:
         # Specs from ruby/spec should still run on all supported Ruby versions.
         # This also ensures the needed ruby_version_is guards are there, see spec/README.md.
         ruby:
-          - ruby-2.7
           - ruby-3.1
+          - ruby-3.2
 
     steps:
-      - uses: actions/checkout@v3
-      - uses: ruby/setup-ruby@v1
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+
+      - uses: ruby/setup-ruby@13e7a03dc3ac6c3798f4570bfead2aed4d96abfb # v1.244.0
         with:
           ruby-version: ${{ matrix.ruby }}
           bundler: none
+
       - run: gem install webrick
+
       - run: ruby ../mspec/bin/mspec
         working-directory: spec/ruby
-      - uses: k0kubun/action-slack@v2.0.0
+        env:
+          CHECK_LEAKS: true
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
@@ -46,8 +64,8 @@ jobs:
               "env": "${{ github.workflow }} / rubyspec @ ${{ matrix.ruby }}",
               "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
               "commit": "${{ github.sha }}",
-              "branch": "${{ github.ref }}".split('/').reverse()[0]
+              "branch": "${{ github.ref_name }}"
             }
         env:
           SLACK_WEBHOOK_URL: ${{ secrets.SIMPLER_ALERTS_URL }} # ruby-lang slack: ruby/simpler-alerts-bot
-        if: ${{ failure() && github.event_name == 'push' }}
+        if: ${{ failure() }}
diff --git a/.github/workflows/ubuntu.yml b/.github/workflows/ubuntu.yml
index b7097cca53..4fbca1170e 100644
--- a/.github/workflows/ubuntu.yml
+++ b/.github/workflows/ubuntu.yml
@@ -3,55 +3,69 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
+      - '**/.document'
   pull_request:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
   cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
 
+permissions:
+  contents: read
+
 jobs:
   make:
     strategy:
       matrix:
-        test_task: ["check", "test-bundler-parallel", "test-bundled-gems"]
-        os:
-          - ubuntu-20.04
-#         - ubuntu-18.04
-        configure: ["", "cppflags=-DRUBY_DEBUG"]
+        # main variables included in the job name
+        test_task: [check]
+        configure: [cppflags=-DRUBY_DEBUG] # default to use more assertions
+        arch: ['']
+        # specify all jobs with `include` to avoid testing duplicated things
         include:
-          - test_task: "check"
-            configure: "--host=i686-$OSTYPE"
-          - test_task: "check"
+          - test_task: check
+          - test_task: check
+            arch: i686
+            configure: '' # test without -DRUBY_DEBUG as well
+          - test_task: check
             configure: "--enable-shared --enable-load-relative"
-            skipped_tests: "TestGem#test_.*_from_binstubs.*"
-            continue-on-skipped_tests: true
-          - test_task: "test-all TESTS=--repeat-count=2"
+          - test_task: test-all TESTS=--repeat-count=2
+          - test_task: test-bundler-parallel
+          - test_task: test-bundled-gems
       fail-fast: false
     env:
       GITPULLOPTIONS: --no-tags origin ${{github.ref}}
       RUBY_DEBUG: ci
-    runs-on: ${{ matrix.os || 'ubuntu-20.04' }}
-    if: ${{ !startsWith(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+      SETARCH: ${{ matrix.arch && format('setarch {0}', matrix.arch) }}
+    runs-on: ubuntu-22.04
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
     steps:
       - run: mkdir build
         working-directory:
       - name: Set ENV
-        env:
-          configure: ${{matrix.configure}}
         run: |
           echo "GNUMAKEFLAGS=-j$((1 + $(nproc --all)))" >> $GITHUB_ENV
-          arch=`echo " $configure" | sed '/.* --host=/!d;s///;s/[- ].*//'`
-          echo "SETARCH=${arch:+setarch $arch}" >> $GITHUB_ENV
       - name: Install libraries
+        env:
+          arch: ${{matrix.arch}}
         run: |
           set -x
-          arch="${SETARCH##* }"
           arch=${arch:+:${arch/i[3-6]86/i386}}
           ${arch:+sudo dpkg --add-architecture ${arch#:}}
           sudo apt-get update -q || :
@@ -65,10 +79,10 @@ jobs:
         run: |
           git config --global advice.detachedHead 0
           git config --global init.defaultBranch garbage
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           path: src
-      - uses: actions/cache@v3
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: src/.downloaded-cache
           key: downloaded-cache
@@ -84,13 +98,13 @@ jobs:
           arch: ${{matrix.arch}}
         run: >-
           $SETARCH ../src/configure -C --disable-install-doc ${{ matrix.configure }}
-          ${arch:+--target=$arch-$OSTYPE}
+          ${arch:+--target=$arch-$OSTYPE --host=$arch-$OSTYPE}
       - run: $SETARCH make incs
+      - run: $SETARCH make prepare-gems
+        if: ${{ matrix.test_task == 'test-bundled-gems' }}
       - run: $SETARCH make
       - run: $SETARCH make leaked-globals
         if: ${{ matrix.test_task == 'check' }}
-      - run: $SETARCH make prepare-gems
-        if: ${{ matrix.test_task == 'check' }}
       - name: Create dummy files in build dir
         run: |
           $SETARCH ./miniruby -e '(("a".."z").to_a+("A".."Z").to_a+("0".."9").to_a+%w[foo bar test zzz]).each{|basename|File.write("#{basename}.rb", "raise %(do not load #{basename}.rb)")}'
@@ -113,15 +127,15 @@ jobs:
           TESTS: ${{ matrix.skipped_tests }}
         if: ${{ matrix.test_task == 'check' && matrix.skipped_tests != '' }}
         continue-on-error: ${{ matrix.continue-on-skipped_tests || false }}
-      - uses: k0kubun/action-slack@v2.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
               "ci": "GitHub Actions",
-              "env": "${{ matrix.os }} / ${{ matrix.test_task }}${{ matrix.configure }}",
+              "env": "${{ github.workflow }} / ${{ matrix.test_task }} ${{ matrix.configure }}${{ matrix.arch }}",
               "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
               "commit": "${{ github.sha }}",
-              "branch": "${{ github.ref }}".split('/').reverse()[0]
+              "branch": "${{ github.ref_name }}"
             }
         env:
           SLACK_WEBHOOK_URL: ${{ secrets.SIMPLER_ALERTS_URL }} # ruby-lang slack: ruby/simpler-alerts-bot
diff --git a/.github/workflows/wasm.yml b/.github/workflows/wasm.yml
index db00db9009..27920b5821 100644
--- a/.github/workflows/wasm.yml
+++ b/.github/workflows/wasm.yml
@@ -3,18 +3,32 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
+      - '**/.document'
   pull_request:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
   cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
 
+permissions:  # added using https://github.com/step-security/secure-workflows
+  contents: read
+
 jobs:
   make:
     strategy:
@@ -34,11 +48,10 @@ jobs:
       GITPULLOPTIONS: --no-tags origin ${{github.ref}}
       WASI_SDK_VERSION_MAJOR: 14
       WASI_SDK_VERSION_MINOR: 0
-      # Use older version, which uses glibc instead of musl, to avoid https://github.com/WebAssembly/binaryen/issues/4401
-      BINARYEN_VERSION: 91
+      BINARYEN_VERSION: 109
       WASMTIME_VERSION: v0.33.0
-    runs-on: ubuntu-20.04
-    if: ${{ !startsWith(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    runs-on: ubuntu-22.04
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
     steps:
       - run: mkdir build
         working-directory:
@@ -46,7 +59,7 @@ jobs:
         run: |
           git config --global advice.detachedHead 0
           git config --global init.defaultBranch garbage
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           path: src
       - name: Install libraries
@@ -67,10 +80,10 @@ jobs:
           wget -O - "$wasmtime_url" | tar xJf -
           sudo ln -fs "$PWD/wasmtime-${WASMTIME_VERSION}-x86_64-linux/wasmtime" /usr/local/bin/wasmtime
 
-          binaryen_tarball="binaryen-version_${BINARYEN_VERSION}-x86-linux.tar.gz"
+          binaryen_tarball="binaryen-version_${BINARYEN_VERSION}-x86_64-linux.tar.gz"
           binaryen_url="https://github.com/WebAssembly/binaryen/releases/download/version_${BINARYEN_VERSION}/${binaryen_tarball}"
           wget -O - "$binaryen_url" | tar xfz -
-          sudo ln -fs "$PWD/binaryen-version_${BINARYEN_VERSION}/wasm-opt" /usr/local/bin/wasm-opt
+          sudo ln -fs "$PWD/binaryen-version_${BINARYEN_VERSION}/bin/wasm-opt" /usr/local/bin/wasm-opt
         working-directory: src
       - name: Set ENV
         run: |
@@ -78,6 +91,18 @@ jobs:
           echo "WASI_SDK_PATH=/opt/wasi-sdk" >> $GITHUB_ENV
       - run: ./autogen.sh
         working-directory: src
+
+      - uses: ruby/setup-ruby@13e7a03dc3ac6c3798f4570bfead2aed4d96abfb # v1.244.0
+        with:
+          ruby-version: '3.0'
+          bundler: none
+
+      - name: Download config.guess with wasi version
+        run: |
+          rm tool/config.guess tool/config.sub
+          ruby tool/downloader.rb -d tool -e gnu config.guess config.sub
+        working-directory: src
+
       - name: Run configure
         run: |
           ../src/configure \
@@ -91,7 +116,8 @@ jobs:
             debugflags="${{ matrix.entry.debugflags }}" \
             wasmoptflags="${{ matrix.entry.wasmoptflags }} ${{ matrix.entry.debugflags }}"
 
-      - run: make ruby
+      # miniruby may not be built when cross-compling
+      - run: make mini ruby
       - name: Run basictest
         run: wasmtime run ./../build/miniruby --mapdir /::./ -- basictest/test.rb
         working-directory: src
@@ -101,6 +127,20 @@ jobs:
           ruby ./bootstraptest/runner.rb --ruby="$(which wasmtime) run $PWD/../build/ruby --mapdir /::./ -- " --verbose "--sets=$NO_THREAD_TESTS"
         working-directory: src
 
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
+        with:
+          payload: |
+            {
+              "ci": "GitHub Actions",
+              "env": "${{ github.workflow }} / ${{ matrix.name }}",
+              "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
+              "commit": "${{ github.sha }}",
+              "branch": "${{ github.ref_name }}"
+            }
+        env:
+          SLACK_WEBHOOK_URL: ${{ secrets.SIMPLER_ALERTS_URL }} # ruby-lang slack: ruby/simpler-alerts-bot
+        if: ${{ failure() && github.event_name == 'push' }}
+
 defaults:
   run:
     working-directory: build
diff --git a/.github/workflows/windows.yml b/.github/workflows/windows.yml
index 9c9d7b9da0..c2bd4881c2 100644
--- a/.github/workflows/windows.yml
+++ b/.github/workflows/windows.yml
@@ -3,108 +3,107 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
+      - '**/.document'
   pull_request:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
   cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
 
+permissions:
+  contents: read
+
 jobs:
   make:
     strategy:
       matrix:
         include:
-          - vs: 2019
           - vs: 2022
+            vcvers: -vcvars_ver=14.2
       fail-fast: false
-    runs-on: windows-${{ matrix.vs < 2022 && '2019' || matrix.vs }}
-    if: ${{ !startsWith(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    runs-on: windows-${{ matrix.vs }}
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
     name: VisualStudio ${{ matrix.vs }}
     env:
       GITPULLOPTIONS: --no-tags origin ${{github.ref}}
       PATCH: C:\msys64\usr\bin\patch.exe
-      OS_VER: windows-${{ matrix.vs < 2022 && '2019' || matrix.vs }}
+      OS_VER: windows-${{ matrix.vs }}
     steps:
       - run: md build
         working-directory:
-      - uses: msys2/setup-msys2@v2
+      - uses: msys2/setup-msys2@61f9e5e925871ba6c9e3e8da24ede83ea27fa91f # v2.27.0
         id: setup-msys2
         with:
           update: true
-          install: >-
-            patch
-        if: ${{ env.OS_VER != 'windows-2019' }}
+          install: bison patch
       - name: patch path
         shell: msys2 {0}
         run: echo PATCH=$(cygpath -wa $(command -v patch)) >> $GITHUB_ENV
         if: ${{ steps.setup-msys2.outcome == 'success' }}
-      - uses: actions/cache@v3
-        with:
-          path: C:\vcpkg\downloads
-          key: ${{ runner.os }}-vcpkg-download-${{ env.OS_VER }}-${{ github.sha }}
-          restore-keys: |
-            ${{ runner.os }}-vcpkg-download-${{ env.OS_VER }}-
-            ${{ runner.os }}-vcpkg-download-
-      - uses: actions/cache@v3
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: C:\vcpkg\installed
-          key: ${{ runner.os }}-vcpkg-installed-${{ matrix.os }}-${{ github.sha }}
+          key: ${{ runner.os }}-vcpkg-installed-windows-${{ matrix.vs }}-${{ github.sha }}
           restore-keys: |
-            ${{ runner.os }}-vcpkg-installed-${{ matrix.os }}-
-            ${{ runner.os }}-vcpkg-installed-
+            ${{ runner.os }}-vcpkg-installed-windows-${{ matrix.vs }}-
+            ${{ runner.os }}-vcpkg-installed-windows-
       - name: Install libraries with vcpkg
         run: |
+          iex "& {$(irm get.scoop.sh)} -RunAsAdmin"
+          Join-Path (Resolve-Path ~).Path "scoop\shims" >> $Env:GITHUB_PATH
+          scoop install cmake@3.31.6
           vcpkg --triplet x64-windows install libffi libyaml openssl readline zlib
-      - uses: actions/cache@v3
-        with:
-          path: C:\Users\runneradmin\AppData\Local\Temp\chocolatey
-          key: ${{ runner.os }}-chocolatey-${{ env.OS_VER }}-${{ github.sha }}
-          restore-keys: |
-            ${{ runner.os }}-chocolatey-${{ env.OS_VER }}-
-            ${{ runner.os }}-chocolatey-
-      - name: Install libraries with chocolatey
-        run: |
-          # Using Choco-Install for retries, but it doesn't detect failures properly
-          # if you pass multiple package names in a single command.
-          Choco-Install -PackageName winflexbison3
-        shell: pwsh
+        shell:
+          pwsh
       - name: git config
         run: |
           git config --global core.autocrlf false
           git config --global core.eol lf
           git config --global advice.detachedHead 0
           git config --global init.defaultBranch garbage
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           path: src
-      - uses: actions/cache@v3
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: src/.downloaded-cache
           key: downloaded-cache
       - name: setup env
         # %TEMP% is inconsistent with %TMP% and test-all expects they are consistent.
         # https://github.com/actions/virtual-environments/issues/712#issuecomment-613004302
+        # msys2/setup-msys2 installs MSYS2 to D:/a/_temp/msys64/usr/bin
         run: |
-          set VS=${{ matrix.vs }}
-          set VCVARS=${{ matrix.vcvars }}
+          set Path=D:/a/_temp/msys64/usr/bin;%Path%
           if not "%VCVARS%" == "" goto :vcset
-            set VCVARS="C:\Program Files (x86)\Microsoft Visual Studio\%VS%\Enterprise\VC\Auxiliary\Build\vcvars64.bat"
-            if not exist %VCVARS% set VCVARS="C:\Program Files\Microsoft Visual Studio\%VS%\Enterprise\VC\Auxiliary\Build\vcvars64.bat"
+            set VCVARS="C:\Program Files (x86)\Microsoft Visual Studio\${{ matrix.vs }}\Enterprise\VC\Auxiliary\Build\vcvars64.bat"
+            if not exist %VCVARS% set VCVARS="C:\Program Files\Microsoft Visual Studio\${{ matrix.vs }}\Enterprise\VC\Auxiliary\Build\vcvars64.bat"
           :vcset
           set | C:\msys64\usr\bin\sort > old.env
-          call %VCVARS%
+          call %VCVARS% ${{ matrix.vcvers || ''}}
           set TMP=%USERPROFILE%\AppData\Local\Temp
           set TEMP=%USERPROFILE%\AppData\Local\Temp
           set /a TEST_JOBS=(15 * %NUMBER_OF_PROCESSORS% / 10) > nul
           set | C:\msys64\usr\bin\sort > new.env
           C:\msys64\usr\bin\comm -13 old.env new.env >> %GITHUB_ENV%
           del *.env
+      - name: compiler version
+        run: cl
       - name: link libraries
         run: |
           for %%I in (C:\vcpkg\installed\x64-windows\bin\*.dll) do (
@@ -121,18 +120,16 @@ jobs:
       - run: nmake extract-extlibs
       - run: nmake
         env:
-          YACC: win_bison
+          YACC: bison.exe
       - run: nmake test
         timeout-minutes: 5
+      - run: nmake test-spec
+        timeout-minutes: 10
       - run: nmake test-all
         env:
           RUBY_TESTOPTS: -j${{env.TEST_JOBS}} --job-status=normal
         timeout-minutes: 60
-        continue-on-error: ${{ matrix.continue-on-error || false }}
-      - run: nmake test-spec
-        timeout-minutes: 10
-        continue-on-error: ${{ matrix.continue-on-error || false }}
-      - uses: k0kubun/action-slack@v2.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
@@ -140,7 +137,7 @@ jobs:
               "env": "VS${{ matrix.vs }} / ${{ matrix.test_task || 'check' }}",
               "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
               "commit": "${{ github.sha }}",
-              "branch": "${{ github.ref }}".split('/').reverse()[0]
+              "branch": "${{ github.ref_name }}"
             }
         env:
           SLACK_WEBHOOK_URL: ${{ secrets.SIMPLER_ALERTS_URL }} # ruby-lang slack: ruby/simpler-alerts-bot
diff --git a/.github/workflows/yjit-ubuntu.yml b/.github/workflows/yjit-ubuntu.yml
index beec059e0c..0b7b9046e9 100644
--- a/.github/workflows/yjit-ubuntu.yml
+++ b/.github/workflows/yjit-ubuntu.yml
@@ -3,47 +3,90 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
+      - '**/.document'
   pull_request:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
   cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
 
+permissions:
+  contents: read
+
 jobs:
+  cargo:
+    name: Rust cargo test
+    # GitHub Action's image seems to already contain a Rust 1.58.0.
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      # For now we can't run cargo test --offline because it complains about the
+      # capstone dependency, even though the dependency is optional
+      #- run: cargo test --offline
+      - run: RUST_BACKTRACE=1 cargo test
+        working-directory: yjit
+      # Also compile and test with all features enabled
+      - run: RUST_BACKTRACE=1 cargo test --all-features
+        working-directory: yjit
+      # Check that we can build in release mode too
+      - run: cargo build --release
+        working-directory: yjit
   make:
     strategy:
+      fail-fast: false
       matrix:
-        test_task: ["check"] # "test-bundler-parallel",
-        os:
-          - ubuntu-20.04
-#         - ubuntu-18.04
-        yjit_opts: [
-          "--yjit",
-          "--yjit --yjit-call-threshold=1",
-        ]
-        configure: ["", "cppflags=-DRUBY_DEBUG"]
         include:
+          - test_task: 'yjit-bindgen'
+            hint: 'To fix: use patch in logs'
+            configure: '--with-gcc=clang-14 --enable-yjit=dev'
+            libclang_path: '/usr/lib/llvm-14/lib/libclang.so.1'
+
+          - test_task: "check"
+            # YJIT should be automatically built in release mode on x86-64 Linux with rustc present
+            #configure: "--enable-yjit RUSTC='rustc +1.58.0'"
+            configure: "RUSTC='rustc +1.58.0'"
+            rust_version: "1.58.0"
+
+          - test_task: "check"
+            configure: "--enable-yjit=dev"
+
+          - test_task: "check"
+            configure: "--enable-yjit=dev"
+            yjit_opts: "--yjit-call-threshold=1 --yjit-verify-ctx"
+
           - test_task: "test-all TESTS=--repeat-count=2"
-            os: ubuntu-20.04
-            configure: ""
-            yjit_enable_env: RUBY_YJIT_ENABLE
+            configure: "--enable-yjit=dev"
+
           - test_task: "test-bundled-gems"
-            os: ubuntu-20.04
-            configure: "cppflags=-DRUBY_DEBUG"
-            yjit_enable_env: RUBY_YJIT_ENABLE
-      fail-fast: false
+            configure: "--enable-yjit=dev"
+
+          - test_task: "yjit-bench"
+            configure: "--enable-yjit=dev"
+            yjit_bench_opts: "--yjit-stats"
     env:
       GITPULLOPTIONS: --no-tags origin ${{github.ref}}
       RUN_OPTS: ${{ matrix.yjit_opts }}
+      YJIT_BENCH_OPTS: ${{ matrix.yjit_bench_opts }}
       RUBY_DEBUG: ci
-    runs-on: ${{ matrix.os }}
-    if: ${{ !startsWith(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+      BUNDLE_JOBS: 8 # for yjit-bench
+    runs-on: ubuntu-22.04
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
     steps:
       - run: mkdir build
         working-directory:
@@ -52,14 +95,17 @@ jobs:
           set -x
           sudo apt-get update -q || :
           sudo apt-get install --no-install-recommends -q -y build-essential libssl-dev libyaml-dev libreadline6-dev zlib1g-dev libncurses5-dev libffi-dev bison autoconf ruby
+      - name: Install Rust
+        if: ${{ matrix.rust_version }}
+        run: rustup install ${{ matrix.rust_version }} --profile minimal
       - name: git config
         run: |
           git config --global advice.detachedHead 0
           git config --global init.defaultBranch garbage
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           path: src
-      - uses: actions/cache@v3
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: src/.downloaded-cache
           key: downloaded-cache
@@ -74,12 +120,12 @@ jobs:
       - run: ./autogen.sh
         working-directory: src
       - name: Run configure
-        run: ../src/configure -C --disable-install-doc ${{ matrix.configure }}
+        run: ../src/configure -C --disable-install-doc --prefix=$(pwd)/install ${{ matrix.configure }}
       - run: make incs
-      - run: make
-      - run: make leaked-globals
-        if: ${{ matrix.test_task == 'check' }}
       - run: make prepare-gems
+        if: ${{ matrix.test_task == 'test-bundled-gems' }}
+      - run: make -j
+      - run: make leaked-globals
         if: ${{ matrix.test_task == 'check' }}
       - name: Create dummy files in build dir
         run: |
@@ -87,22 +133,33 @@ jobs:
         if: ${{ matrix.test_task == 'check' }}
       - name: Enable YJIT through ENV
         run: echo "RUBY_YJIT_ENABLE=1" >> $GITHUB_ENV
-        if: ${{ matrix.yjit_enable_env }}
-      - run: make -s ${{ matrix.test_task }} RUN_OPTS="$RUN_OPTS"
+      # Check that the binary was built with YJIT
+      - name: Check YJIT enabled
+        run: ./miniruby --yjit -v | grep "+YJIT"
+      - name: make ${{ matrix.test_task }}
+        run: make -s -j ${{ matrix.test_task }} RUN_OPTS="$RUN_OPTS" YJIT_BENCH_OPTS="$YJIT_BENCH_OPTS"
         timeout-minutes: 60
         env:
           RUBY_TESTOPTS: "-q --tty=no"
           TEST_BUNDLED_GEMS_ALLOW_FAILURES: ""
           PRECHECK_BUNDLED_GEMS: "no"
-      - uses: k0kubun/action-slack@v2.0.0
+          LIBCLANG_PATH: ${{ matrix.libclang_path }}
+        continue-on-error: ${{ matrix.test_task == 'yjit-bench' }}
+      - name: Show ${{ github.event.pull_request.base.ref }} GitHub URL for yjit-bench comparison
+        run: echo "https://github.com/${BASE_REPO}/commit/${BASE_SHA}"
+        env:
+          BASE_REPO: ${{ github.event.pull_request.base.repo.full_name }}
+          BASE_SHA: ${{ github.event.pull_request.base.sha }}
+        if: ${{ matrix.test_task == 'yjit-bench' && startsWith(github.event_name, 'pull') }}
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
               "ci": "GitHub Actions",
-              "env": "${{ matrix.os }} / ${{ matrix.test_task }}${{ matrix.configure }}",
+              "env": "${{ github.workflow }} / ${{ matrix.test_task }} ${{ matrix.configure }}",
               "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
               "commit": "${{ github.sha }}",
-              "branch": "${{ github.ref }}".split('/').reverse()[0]
+              "branch": "${{ github.ref_name }}"
             }
         env:
           SLACK_WEBHOOK_URL: ${{ secrets.SIMPLER_ALERTS_URL }} # ruby-lang slack: ruby/simpler-alerts-bot
diff --git a/.github/workflows/yjit_asm_tests.yml b/.github/workflows/yjit_asm_tests.yml
deleted file mode 100644
index a7e05066dd..0000000000
--- a/.github/workflows/yjit_asm_tests.yml
+++ /dev/null
@@ -1,38 +0,0 @@
-name: YJIT x86 assembler tests
-
-on:
-  push:
-    paths-ignore:
-      - 'doc/**'
-      - '**.md'
-      - '**.rdoc'
-  pull_request:
-    paths-ignore:
-      - 'doc/**'
-      - '**.md'
-      - '**.rdoc'
-
-concurrency:
-  group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
-  cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
-
-jobs:
-  test:
-    runs-on: ubuntu-latest
-    if: ${{ !startsWith(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
-    steps:
-      - name: Install dependencies
-        run: |
-          set -x
-          sudo apt-get update -q || :
-          sudo apt-get install --no-install-recommends -q -y build-essential
-      - name: git config
-        run: |
-          git config --global advice.detachedHead 0
-          git config --global init.defaultBranch garbage
-      - uses: actions/checkout@v3
-        with:
-          path: src
-      - name: Run ASM tests
-        run: ./misc/test_yjit_asm.sh
-        working-directory: src
diff --git a/.gitignore b/.gitignore
index 675020fa91..99d32a1825 100644
--- a/.gitignore
+++ b/.gitignore
@@ -14,6 +14,7 @@
 *.inc
 *.log
 *.o
+*.o.tmp
 *.obj
 *.old
 *.orig
@@ -25,6 +26,7 @@
 *.sav
 *.sl
 *.so
+*.so.*
 *.swp
 *.yarb
 *~
@@ -127,6 +129,7 @@ lcov*.info
 /ruby-runner
 /ruby-runner.h
 /ruby-man.rd.gz
+/rubyspec_temp
 /run.gdb
 /sizes.c
 /static-ruby
@@ -144,6 +147,8 @@ lcov*.info
 
 /bin/*.exe
 /bin/*.dll
+/bin/goruby
+/bin/ruby
 
 # /benchmark/
 /benchmark/bm_require.data
@@ -218,6 +223,9 @@ lcov*.info
 /lib/ruby/[1-9]*.*
 /lib/ruby/vendor_ruby
 
+# /misc/
+/misc/**/__pycache__
+
 # /spec/bundler
 /.rspec_status
 
@@ -229,9 +237,14 @@ lcov*.info
 /win32/*.ico
 
 # MJIT
-/rb_mjit_header.h
-/mjit_config.h
 /include/ruby-*/*/rb_mjit_min_header-*.h
+/lib/ruby_vm/mjit/instruction.rb
+/mjit_config.h
+/rb_mjit_header.h
+
+# YJIT
+/yjit-bench
+/yjit_exit_locations.dump
 
 # /wasm/
 /wasm/tests/*.wasm
diff --git a/.indent.pro b/.indent.pro
new file mode 100644
index 0000000000..1d61cbcad1
--- /dev/null
+++ b/.indent.pro
@@ -0,0 +1,32 @@
+-bap
+-nbbb
+-nbc
+-br
+-brs
+-nbs
+-ncdb
+-nce
+-cdw
+-cli2
+-cbi2
+-ndj
+-ncs
+-nfc1
+-i4
+-l120
+-lp
+-npcs
+-psl
+-sc
+-sob
+-sbi4
+-nut
+-par
+
+-TID
+-TVALUE
+-Tst_data_t
+-Tst_index_t
+-Tst_table
+-Trb_data_type_t
+-TFILE
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index a34d3692af..0000000000
--- a/.travis.yml
+++ /dev/null
@@ -1,234 +0,0 @@
-# -*- YAML -*-
-# Copyright (C) 2011 Urabe, Shyouhei.  All rights reserved.
-#
-# This file is  a part of the programming language  Ruby.  Permission is hereby
-# granted,  to either  redistribute  or  modify this  file,  provided that  the
-# conditions  mentioned in  the file  COPYING are  met.  Consult  the  file for
-# details.
-
-# We only manage non-amd64 free pipelines.
-# https://docs.travis-ci.com/user/billing-overview/
-
-language: c
-
-os: linux
-
-if: commit_message !~ /^\[DOC\]/
-
-dist: focal
-
-git:
-  quiet: true
-
-cache:
-  ccache: true
-  directories:
-    - $HOME/config_2nd
-    - $HOME/.downloaded-cache
-
-env:
-  global:
-    # The tests skipped in `make test-all`.
-    - TEST_ALL_SKIPPED_TESTS=
-    # The tests executed separately by `make test-all`.
-    - TEST_ALL_SEPARATED_TESTS=
-    # Reset timestamps early
-    - _=$(touch NEWS && find . -type f -exec touch -r NEWS {} +)
-    - CONFIGURE_TTY=no
-    - CCACHE_COMPILERCHECK=none
-    - CCACHE_NOCOMPRESS=1
-    - CCACHE_MAXSIZE=512Mi
-    - NPROC="`nproc`"
-    # JOBS and SETARCH are overridden when necessary; see below.
-    - JOBS=-j$((1+${NPROC}))
-    - SETARCH=
-    - RUBY_PREFIX=/tmp/ruby-prefix
-    - GEMS_FOR_TEST='timezone tzinfo'
-    # https://github.com/travis-ci/travis-build/blob/e411371dda21430a60f61b8f3f57943d2fe4d344/lib/travis/build/bash/travis_apt_get_options.bash#L7
-    - travis_apt_get_options='--allow-downgrades --allow-remove-essential --allow-change-held-packages'
-    - travis_apt_get_options="-yq --no-install-suggests --no-install-recommends $travis_apt_get_options"
-    # -O1 is faster than -O3 in our tests.
-    - optflags=-O1
-    # -g0 disables backtraces when SEGV.  Do not set that.
-    - debugflags=-ggdb3
-
-.org.ruby-lang.ci.matrix-definitions:
-
-  - &gcc-10
-    compiler: gcc-10
-    before_install:
-      - tool/travis_retry.sh sudo bash -c "rm -rf '${TRAVIS_ROOT}/var/lib/apt/lists/'* && exec apt-get update -yq"
-      - >-
-        tool/travis_retry.sh sudo -E apt-get $travis_apt_get_options install
-        ccache
-        gcc-10
-        g++-10
-        libffi-dev
-        libncurses-dev
-        libncursesw5-dev
-        libreadline-dev
-        libssl-dev
-        libyaml-dev
-        openssl
-        zlib1g-dev
-
-  # --------
-
-  - &arm64-linux
-    name: arm64-linux
-    arch: arm64
-    <<: *gcc-10
-
-  - &ppc64le-linux
-    name: ppc64le-linux
-    arch: ppc64le
-    <<: *gcc-10
-
-  - &s390x-linux
-    name: s390x-linux
-    arch: s390x
-    <<: *gcc-10
-
-  - &arm32-linux
-    name: arm32-linux
-    arch: arm64
-    # https://packages.ubuntu.com/focal/crossbuild-essential-armhf
-    compiler: arm-linux-gnueabihf-gcc
-    env:
-      - SETARCH='setarch linux32 --verbose --32bit'
-      # The "TestReadline#test_interrupt_in_other_thread" started failing on arm32
-      # from https://www.travis-ci.com/github/ruby/ruby/jobs/529005145
-      - TEST_ALL_SKIPPED_TESTS=test_interrupt_in_other_thread
-    before_install:
-      - sudo dpkg --add-architecture armhf
-      - tool/travis_retry.sh sudo bash -c "rm -rf '${TRAVIS_ROOT}/var/lib/apt/lists/'* && exec apt-get update -yq"
-      - >-
-        tool/travis_retry.sh sudo -E apt-get $travis_apt_get_options install
-        ccache
-        crossbuild-essential-armhf
-        libc6:armhf
-        libstdc++-10-dev:armhf
-        libffi-dev:armhf
-        libncurses-dev:armhf
-        libncursesw5-dev:armhf
-        libreadline-dev:armhf
-        libssl-dev:armhf
-        linux-libc-dev:armhf
-        zlib1g-dev:armhf
-
-matrix:
-  include:
-    # Build every commit (Allowed Failures):
-    - <<: *arm32-linux
-    # Comment out as the 2nd arm64 pipeline is unstable.
-    # - <<: *arm64-linux
-    - <<: *ppc64le-linux
-    - <<: *s390x-linux
-  allow_failures:
-    # We see multiple errors indicating errors on the Travis environment itself in a short while:
-    # https://app.travis-ci.com/github/ruby/ruby/jobs/544382885
-    # https://app.travis-ci.com/github/ruby/ruby/jobs/544361370
-    # It's not a fault of Ruby's arm32 support but just Travis arm32 seems unsable.
-    - name: arm32-linux
-    # - name: arm64-linux
-    # We see "Some worker was crashed." in about 40% of recent ppc64le-linux jobs
-    # e.g. https://app.travis-ci.com/github/ruby/ruby/jobs/530959548
-    - name: ppc64le-linux
-    # Tentatively disable, because often hungs up **after** all tests
-    # have finished successfully and saving caches.
-    - name: s390x-linux
-  fast_finish: true
-
-before_script:
-  - . tool/ci_functions.sh
-  - |-
-    if [ -n "${TEST_ALL_SKIPPED_TESTS}" ]; then
-      TEST_ALL_OPTS="${TEST_ALL_OPTS} $(ci_to_excluded_test_opts "${TEST_ALL_SKIPPED_TESTS}")"
-      if [ -z "${TEST_ALL_SEPARATED_TESTS}" ]; then
-        TEST_ALL_SEPARATED_TESTS="${TEST_ALL_SKIPPED_TESTS}"
-      fi
-    fi
-  - |-
-    if [ -n "${TEST_ALL_SEPARATED_TESTS}" ]; then
-      TEST_ALL_OPTS_SEPARATED="$(ci_to_included_test_opts "${TEST_ALL_SEPARATED_TESTS}")"
-    fi
-  - echo TEST_ALL_OPTS="${TEST_ALL_OPTS}" TEST_ALL_OPTS_SEPARATED="${TEST_ALL_OPTS_SEPARATED}"
-  - rm -fr .ext autom4te.cache
-  - |-
-    [ -d ~/.downloaded-cache ] ||
-    mkdir ~/.downloaded-cache
-  - ln -s ~/.downloaded-cache
-  - "> config.status"
-  - "> .rbconfig.time"
-  - sed -f tool/prereq.status template/Makefile.in common.mk > Makefile
-  - make -s $JOBS up
-  - make -s $JOBS srcs
-  - rm -f config.status Makefile rbconfig.rb .rbconfig.time
-  - |-
-    if [ -d ~/config_2nd ]; then
-      cp -pr ~/config_2nd build
-    else
-      mkdir build
-    fi
-  - mkdir config_1st config_2nd
-  - chmod -R a-w .
-  - chmod -R u+w build config_1st config_2nd
-  - cd build
-  - |-
-    case "$CC" in
-    gcc*)   CC="ccache $CC${GCC_FLAGS:+ }$GCC_FLAGS -fno-diagnostics-color";;
-    clang*) CC="ccache $CC${GCC_FLAGS:+ }$GCC_FLAGS -fno-color-diagnostics";;
-    esac
-  - |-
-    [ ! -f config.cache ] ||
-    [ "$CC" = "`sed -n s/^ac_cv_prog_CC=//p config.cache`" ] ||
-    (set -x; exec rm config.cache)
-  - $SETARCH ../configure -C --disable-install-doc --prefix=$RUBY_PREFIX $CONFIG_FLAG
-  - cp -pr config.cache config.status .ext/include ../config_1st
-  - $SETARCH make reconfig
-  - cp -pr config.cache config.status .ext/include ../config_2nd
-  - (cd .. && exec diff -ru config_1st config_2nd)
-  - chmod u+w ..
-  - rm -rf ~/config_2nd
-  - mv ../config_2nd ~
-  - chmod u-w ..
-  - $SETARCH make -s $JOBS
-  - make -s install
-  - |-
-    [ -z "${GEMS_FOR_TEST}" ] ||
-    $RUBY_PREFIX/bin/gem install --no-document $GEMS_FOR_TEST
-  - echo "raise 'do not load ~/.irbrc in test'" > ~/.irbrc
-
-script:
-  - $SETARCH make -s test -o showflags TESTOPTS="${TESTOPTS=$JOBS -q --tty=no}"
-  - ../tool/travis_wait.sh $SETARCH make -s test-all -o exts TESTOPTS="$JOBS -q --tty=no ${TEST_ALL_OPTS}" RUBYOPT="-w"
-  # Run the failing tests separately returning ok status to check if it works,
-  # visualize them.
-  - |
-    if [ -n "${TEST_ALL_OPTS_SEPARATED}" ]; then
-      $SETARCH make -s test-all -o exts TESTOPTS="$JOBS -v --tty=no ${TEST_ALL_OPTS_SEPARATED}" RUBYOPT="-w" || :
-    fi
-  - $SETARCH make -s test-spec MSPECOPT=-ff # not using `-j` because sometimes `mspec -j` silently dies
-  - $SETARCH make -s -o showflags leaked-globals
-
-# We enable Travis on the specific branches or forked repositories here.
-if: (repo = ruby/ruby AND (branch = master OR branch =~ /^ruby_\d_\d$/)) OR repo != ruby/ruby
-
-# We want to be notified when something happens.
-notifications:
-  irc:
-    channels:
-      - "chat.freenode.net#ruby-core"
-    on_success: change # [always|never|change] # default: always
-    on_failure: always # [always|never|change] # default: always
-    template:
-      - "%{message} by @%{author}: See %{build_url}"
-
-  webhooks:
-    urls:
-      - secure: mRsoS/UbqDkKkW5p3AEqM27d4SZnV6Gsylo3bm8T/deltQzTsGzZwrm7OIBXZv0UFZdE68XmPlyHfZFLSP2V9QZ7apXMf9/vw0GtcSe1gchtnjpAPF6lYBn7nMCbVPPx9cS0dwL927fjdRM1vj7IKZ2bk4F0lAJ25R25S6teqdk= # ruby-lang slack: ruby/simpler-alerts-bot (travis)
-    on_success: never
-    on_failure: always
-
-  email:
-    - jaruga@ruby-lang.org
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 7363c106a2..13df6087ca 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -1,5 +1 @@
-Please see the [official issue tracker], [doc/contributing.rdoc] and wiki [HowToContribute].
-
-[official issue tracker]: https://bugs.ruby-lang.org
-[doc/contributing.rdoc]: contributing.rdoc
-[HowToContribute]: https://bugs.ruby-lang.org/projects/ruby/wiki/HowToContribute
+See ["Contributing to Ruby"](https://docs.ruby-lang.org/en/master/contributing_md.html), which includes setup and build instructions.
diff --git a/LEGAL b/LEGAL
index 9645728efe..0423d57ac9 100644
--- a/LEGAL
+++ b/LEGAL
@@ -979,7 +979,6 @@ mentioned below.
     {MIT License}[rdoc-label:label-MIT+License]
 
 [lib/rubygems/resolver/molinillo]
-[lib/bundler/vendor/molinillo]
 
   molinillo is under the following license.
 
@@ -988,6 +987,15 @@ mentioned below.
 
     {MIT License}[rdoc-label:label-MIT+License]
 
+[lib/bundler/vendor/pub_grub]
+
+  pub_grub is under the following license.
+
+  >>>
+    Copyright (c) 2018 John Hawthorn
+
+    {MIT License}[rdoc-label:label-MIT+License]
+
 [lib/bundler/vendor/connection_pool]
 
   connection_pool is under the following license.
diff --git a/NEWS.md b/NEWS.md
index e75877c7a9..f6c3c6fc97 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -23,40 +23,40 @@ Note that each entry is kept to a minimum, see links for details.
 * A proc that accepts a single positional argument and keywords will
   no longer autosplat. [[Bug #18633]]
 
-  ```ruby
-  proc{|a, **k| a}.call([1, 2])
-  # Ruby 3.1 and before
-  # => 1
-  # Ruby 3.2 and after
-  # => [1, 2]
-  ```
+    ```ruby
+    proc{|a, **k| a}.call([1, 2])
+    # Ruby 3.1 and before
+    # => 1
+    # Ruby 3.2 and after
+    # => [1, 2]
+    ```
 
 * Constant assignment evaluation order for constants set on explicit
   objects has been made consistent with single attribute assignment
-  evaluation order.  With this code:
+  evaluation order. With this code:
 
     ```ruby
     foo::BAR = baz
     ```
 
-  `foo` is now called before `baz`. Similarly, for multiple assignment
-  to constants,  left-to-right evaluation order is used.  With this
-  code:
+    `foo` is now called before `baz`. Similarly, for multiple assignments
+    to constants,  left-to-right evaluation order is used. With this
+    code:
 
     ```ruby
-      foo1::BAR1, foo2::BAR2 = baz1, baz2
+    foo1::BAR1, foo2::BAR2 = baz1, baz2
     ```
 
-  The following evaluation order is now used:
+    The following evaluation order is now used:
 
-  1. `foo1`
-  2. `foo2`
-  3. `baz1`
-  4. `baz2`
+    1. `foo1`
+    2. `foo2`
+    3. `baz1`
+    4. `baz2`
 
-  [[Bug #15928]]
+    [[Bug #15928]]
 
-* Find pattern is no longer experimental.
+* "Find pattern" is no longer experimental.
   [[Feature #18585]]
 
 * Methods taking a rest parameter (like `*args`) and wishing to delegate keyword
@@ -90,83 +90,487 @@ Note that each entry is kept to a minimum, see links for details.
     foo(k: 1)
     ```
 
-## Command line options
-
 ## Core classes updates
 
 Note: We're only listing outstanding class updates.
 
+* Fiber
+
+    * Introduce Fiber.[] and Fiber.[]= for inheritable fiber storage.
+      Introduce Fiber#storage and Fiber#storage= (experimental) for
+      getting and resetting the current storage.  Introduce
+      `Fiber.new(storage:)` for setting the storage when creating a
+      fiber. [[Feature #19078]]
+
+        Existing Thread and Fiber local variables can be tricky to use.
+        Thread-local variables are shared between all fibers, making it
+        hard to isolate, while Fiber-local variables can be hard to
+        share.  It is often desirable to define unit of execution
+        ("execution context") such that some state is shared between all
+        fibers and threads created in that context.  This is what Fiber
+        storage provides.
+
+        ```ruby
+        def log(message)
+          puts "#{Fiber[:request_id]}: #{message}"
+        end
+
+        def handle_requests
+          while request = read_request
+            Fiber.schedule do
+              Fiber[:request_id] = SecureRandom.uuid
+
+              request.messages.each do |message|
+                Fiber.schedule do
+                  log("Handling #{message}") # Log includes inherited request_id.
+                end
+              end
+            end
+          end
+        end
+        ```
+
+        You should generally consider Fiber storage for any state which
+        you want to be shared implicitly between all fibers and threads
+        created in a given context, e.g. a connection pool, a request
+        id, a logger level, environment variables, configuration, etc.
+
+* Fiber::Scheduler
+
+    * Introduce `Fiber::Scheduler#io_select` for non-blocking IO.select.
+      [[Feature #19060]]
+
+* IO
+
+    * Introduce IO#timeout= and IO#timeout which can cause
+      IO::TimeoutError to be raised if a blocking operation exceeds the
+      specified timeout. [[Feature #18630]]
+
+        ```ruby
+        STDIN.timeout = 1
+        STDIN.read # => Blocking operation timed out! (IO::TimeoutError)
+        ```
+
+    * Introduce `IO.new(..., path:)` and promote `File#path` to `IO#path`.
+      [[Feature #19036]]
+
+* Class
+
+    * Class#attached_object, which returns the object for which
+      the receiver is the singleton class. Raises TypeError if the
+      receiver is not a singleton class.
+      [[Feature #12084]]
+
+        ```ruby
+        class Foo; end
+
+        Foo.singleton_class.attached_object        #=> Foo
+        Foo.new.singleton_class.attached_object    #=> #<Foo:0x000000010491a370>
+        Foo.attached_object                        #=> TypeError: `Foo' is not a singleton class
+        nil.singleton_class.attached_object        #=> TypeError: `NilClass' is not a singleton class
+        ```
+
+* Data
+
+    * New core class to represent simple immutable value object. The class is
+      similar to Struct and partially shares an implementation, but has more
+      lean and strict API. [[Feature #16122]]
+
+        ```ruby
+        Measure = Data.define(:amount, :unit)
+        distance = Measure.new(100, 'km')            #=> #<data Measure amount=100, unit="km">
+        weight = Measure.new(amount: 50, unit: 'kg') #=> #<data Measure amount=50, unit="kg">
+        weight.with(amount: 40)                      #=> #<data Measure amount=40, unit="kg">
+        weight.amount                                #=> 50
+        weight.amount = 40                           #=> NoMethodError: undefined method `amount='
+        ```
+
+* Encoding
+
+    * Encoding#replicate has been deprecated and will be removed in 3.3. [[Feature #18949]]
+    * The dummy `Encoding::UTF_16` and `Encoding::UTF_32` encodings no longer
+      try to dynamically guess the endian based on a byte order mark.
+      Use `Encoding::UTF_16BE`/`UTF_16LE` and `Encoding::UTF_32BE`/`UTF_32LE` instead.
+      This change speeds up getting the encoding of a String. [[Feature #18949]]
+    * Limit maximum encoding set size by 256.
+      If exceeding maximum size, `EncodingError` will be raised. [[Feature #18949]]
+
+* Enumerator
+
+    * Enumerator.product has been added.  Enumerator::Product is the implementation. [[Feature #18685]]
+
+* Exception
+
+    * Exception#detailed_message has been added.
+      The default error printer calls this method on the Exception object
+      instead of #message. [[Feature #18564]]
+
 * Hash
+
     * Hash#shift now always returns nil if the hash is
       empty, instead of returning the default value or
       calling the default proc. [[Bug #16908]]
 
+* Integer
+
+    * Integer#ceildiv has been added. [[Feature #18809]]
+
 * Kernel
+
     * Kernel#binding raises RuntimeError if called from a non-Ruby frame
       (such as a method defined in C). [[Bug #18487]]
 
 * MatchData
+
     * MatchData#byteoffset has been added. [[Feature #13110]]
+    * MatchData#deconstruct has been added. [[Feature #18821]]
+    * MatchData#deconstruct_keys has been added. [[Feature #18821]]
 
 * Module
+
     * Module.used_refinements has been added. [[Feature #14332]]
     * Module#refinements has been added. [[Feature #12737]]
     * Module#const_added has been added. [[Feature #17881]]
+    * Module#undefined_instance_methods has been added. [[Feature #12655]]
 
 * Proc
+
     * Proc#dup returns an instance of subclass. [[Bug #17545]]
     * Proc#parameters now accepts lambda keyword. [[Feature #15357]]
 
+* Process
+    * Added `RLIMIT_NPTS` constant to FreeBSD platform
+
+* Regexp
+
+    * The cache-based optimization is introduced.
+      Many (but not all) Regexp matching is now in linear time, which
+      will prevent regular expression denial of service (ReDoS)
+      vulnerability. [[Feature #19104]]
+
+    * Regexp.linear_time? is introduced. [[Feature #19194]]
+
+    * Regexp.new now supports passing the regexp flags not only as an Integer,
+      but also as a String.  Unknown flags raise ArgumentError.
+      Otherwise, anything other than `true`, `false`, `nil` or Integer will be warned.
+      [[Feature #18788]]
+
+    * Regexp.timeout= has been added. Also, Regexp.new new supports timeout keyword.
+      See [[Feature #17837]]
+
 * Refinement
+
     * Refinement#refined_class has been added. [[Feature #12737]]
 
+* RubyVM::AbstractSyntaxTree
+
+    * Add `error_tolerant` option for `parse`, `parse_file` and `of`. [[Feature #19013]]
+      With this option
+
+        1. SyntaxError is suppressed
+        2. AST is returned for invalid input
+        3. `end` is complemented when a parser reaches to the end of input but `end` is insufficient
+        4. `end` is treated as keyword based on indent
+
+        ```ruby
+        # Without error_tolerant option
+        root = RubyVM::AbstractSyntaxTree.parse(<<~RUBY)
+        def m
+          a = 10
+          if
+        end
+        RUBY
+        # => <internal:ast>:33:in `parse': syntax error, unexpected `end' (SyntaxError)
+
+        # With error_tolerant option
+        root = RubyVM::AbstractSyntaxTree.parse(<<~RUBY, error_tolerant: true)
+        def m
+          a = 10
+          if
+        end
+        RUBY
+        p root # => #<RubyVM::AbstractSyntaxTree::Node:SCOPE@1:0-4:3>
+
+        # `end` is treated as keyword based on indent
+        root = RubyVM::AbstractSyntaxTree.parse(<<~RUBY, error_tolerant: true)
+        module Z
+          class Foo
+            foo.
+          end
+
+          def bar
+          end
+        end
+        RUBY
+        p root.children[-1].children[-1].children[-1].children[-2..-1]
+        # => [#<RubyVM::AbstractSyntaxTree::Node:CLASS@2:2-4:5>, #<RubyVM::AbstractSyntaxTree::Node:DEFN@6:2-7:5>]
+        ```
+
+    * Add `keep_tokens` option for `parse`, `parse_file` and `of`. Add `#tokens` and `#all_tokens`
+      for RubyVM::AbstractSyntaxTree::Node [[Feature #19070]]
+
+        ```ruby
+        root = RubyVM::AbstractSyntaxTree.parse("x = 1 + 2", keep_tokens: true)
+        root.tokens # => [[0, :tIDENTIFIER, "x", [1, 0, 1, 1]], [1, :tSP, " ", [1, 1, 1, 2]], ...]
+        root.tokens.map{_1[2]}.join # => "x = 1 + 2"
+        ```
+
 * Set
-    * Set is now available as a builtin class without the need for `require "set"`. [[Feature #16989]]
-      It is currently autoloaded via the `Set` constant or a call to `Enumerable#to_set`.
+
+    * Set is now available as a built-in class without the need for `require "set"`. [[Feature #16989]]
+      It is currently autoloaded via the Set constant or a call to Enumerable#to_set.
 
 * String
+
     * String#byteindex and String#byterindex have been added. [[Feature #13110]]
-    * Update Unicode to Version 14.0.0 and Emoji Version 14.0. [[Feature #18037]]
+    * Update Unicode to Version 15.0.0 and Emoji Version 15.0. [[Feature #18639]]
       (also applies to Regexp)
     * String#bytesplice has been added.  [[Feature #18598]]
+    * String#dedup has been added as an alias to String#-@.  [[Feature #18595]]
 
 * Struct
+
     * A Struct class can also be initialized with keyword arguments
-      without `keyword_init: true` on `Struct.new` [[Feature #16806]]
+      without `keyword_init: true` on Struct.new [[Feature #16806]]
+
+        ```ruby
+        Post = Struct.new(:id, :name)
+        Post.new(1, "hello") #=> #<struct Post id=1, name="hello">
+        # From Ruby 3.2, the following code also works without keyword_init: true.
+        Post.new(id: 1, name: "hello") #=> #<struct Post id=1, name="hello">
+        ```
+
+* Thread
+
+    * Thread.each_caller_location is added. [[Feature #16663]]
+
+* Thread::Queue
+
+    * Thread::Queue#pop(timeout: sec) is added. [[Feature #18774]]
+
+* Thread::SizedQueue
+
+    * Thread::SizedQueue#pop(timeout: sec) is added. [[Feature #18774]]
+    * Thread::SizedQueue#push(timeout: sec) is added. [[Feature #18944]]
+
+* Time
+
+    * Time#deconstruct_keys is added, allowing to use Time instances
+      in pattern-matching expressions [[Feature #19071]]
+
+    * Time.new now can parse a string like generated by Time#inspect
+      and return a Time instance based on the given argument.
+      [[Feature #18033]]
+
+* SyntaxError
+    * SyntaxError#path has been added.  [[Feature #19138]]
 
 * TracePoint
+
     * TracePoint#binding now returns `nil` for `c_call`/`c_return` TracePoints.
       [[Bug #18487]]
     * TracePoint#enable `target_thread` keyword argument now defaults to the
-      current thread if `target` and `target_line` keyword arguments are not
-      passed. [[Bug #16889]]
+      current thread if a block is given and `target` and `target_line` keyword
+      arguments are not passed. [[Bug #16889]]
+
+* UnboundMethod
+
+    * `UnboundMethod#==` returns `true` if the actual method is same. For example,
+      `String.instance_method(:object_id) == Array.instance_method(:object_id)`
+      returns `true`. [[Feature #18798]]
+
+    * `UnboundMethod#inspect` does not show the receiver of `instance_method`.
+      For example `String.instance_method(:object_id).inspect` returns
+      `"#<UnboundMethod: Kernel#object_id()>"`
+      (was `"#<UnboundMethod: String(Kernel)#object_id()>"`).
+
+* GC
+
+    * Expose `need_major_gc` via `GC.latest_gc_info`. [GH-6791]
+
+* ObjectSpace
+
+    * `ObjectSpace.dump_all` dump shapes as well. [GH-6868]
 
 ## Stdlib updates
 
-*   The following default gem are updated.
-    * RubyGems 3.4.0.dev
-    * bigdecimal 3.1.2
-    * bundler 2.4.0.dev
-    * cgi 0.3.2
-    * etc 1.4.0
-    * io-console 0.5.11
-    * io-wait 0.2.2.pre1
-    * ipaddr 1.2.4
-    * logger 1.5.1
-    * net-protocol 0.1.3
+* Bundler
+
+    * Bundler now uses [PubGrub] resolver instead of [Molinillo] for performance improvement.
+    * Add --ext=rust support to bundle gem for creating simple gems with Rust extensions.
+      [[GH-rubygems-6149]]
+    * Make cloning git repos faster [[GH-rubygems-4475]]
+
+* RubyGems
+
+    * Add mswin support for cargo builder. [[GH-rubygems-6167]]
+
+* CGI
+
+    * `CGI.escapeURIComponent` and `CGI.unescapeURIComponent` are added.
+      [[Feature #18822]]
+
+* Coverage
+
+    * `Coverage.setup` now accepts `eval: true`. By this, `eval` and related methods are
+      able to generate code coverage. [[Feature #19008]]
+
+    * `Coverage.supported?(mode)` enables detection of what coverage modes are
+      supported. [[Feature #19026]]
+
+* Date
+
+    * Added `Date#deconstruct_keys` and `DateTime#deconstruct_keys` same as [[Feature #19071]]
+
+* ERB
+
+    * `ERB::Util.html_escape` is made faster than `CGI.escapeHTML`.
+        * It no longer allocates a String object when no character needs to be escaped.
+        * It skips calling `#to_s` method when an argument is already a String.
+        * `ERB::Escape.html_escape` is added as an alias to `ERB::Util.html_escape`,
+          which has not been monkey-patched by Rails.
+    * `ERB::Util.url_encode` is made faster using `CGI.escapeURIComponent`.
+    * `-S` option is removed from `erb` command.
+
+* FileUtils
+
+    * Add FileUtils.ln_sr method and `relative:` option to FileUtils.ln_s.
+      [[Feature #18925]]
+
+* IRB
+
+    * debug.gem integration commands have been added: `debug`, `break`, `catch`,
+      `next`, `delete`, `step`, `continue`, `finish`, `backtrace`, `info`
+        * They work even if you don't have `gem "debug"` in your Gemfile.
+        * See also: [What's new in Ruby 3.2's IRB?](https://st0012.dev/whats-new-in-ruby-3-2-irb)
+    * More Pry-like commands and features have been added.
+        * `edit` and `show_cmds` (like Pry's `help`) are added.
+        * `ls` takes `-g` or `-G` option to filter out outputs.
+        * `show_source` is aliased from `$` and accepts unquoted inputs.
+        * `whereami` is aliased from `@`.
+
+* Net::Protocol
+
+    * Improve `Net::BufferedIO` performance. [[GH-net-protocol-14]]
+
+* Pathname
+
+    * Added `Pathname#lutime`. [[GH-pathname-20]]
+
+* Socket
+
+    * Added the following constants for supported platforms.
+        * `SO_INCOMING_CPU`
+        * `SO_INCOMING_NAPI_ID`
+        * `SO_RTABLE`
+        * `SO_SETFIB`
+        * `SO_USER_COOKIE`
+        * `TCP_KEEPALIVE`
+        * `TCP_CONNECTION_INFO`
+
+* SyntaxSuggest
+
+    * The feature of `syntax_suggest` formerly `dead_end` is integrated in Ruby.
+      [[Feature #18159]]
+
+* UNIXSocket
+
+    * Add support for UNIXSocket on Windows. Emulate anonymous sockets. Add
+      support for File.socket? and File::Stat#socket? where possible.
+      [[Feature #19135]]
+
+*   The following default gems are updated.
+
+    * RubyGems 3.4.1
+    * abbrev 0.1.1
+    * benchmark 0.2.1
+    * bigdecimal 3.1.3
+    * bundler 2.4.1
+    * cgi 0.3.6
+    * csv 3.2.6
+    * date 3.3.3
+    * delegate 0.3.0
+    * did_you_mean 1.6.3
+    * digest 3.1.1
+    * drb 2.1.1
+    * english 0.7.2
+    * erb 4.0.2
+    * error_highlight 0.5.1
+    * etc 1.4.2
+    * fcntl 1.0.2
+    * fiddle 1.1.1
+    * fileutils 1.7.0
+    * forwardable 1.3.3
+    * getoptlong 0.2.0
+    * io-console 0.6.0
+    * io-nonblock 0.2.0
+    * io-wait 0.3.0
+    * ipaddr 1.2.5
+    * irb 1.6.2
+    * json 2.6.3
+    * logger 1.5.3
+    * mutex_m 0.1.2
+    * net-http 0.4.0
+    * net-protocol 0.2.1
+    * nkf 0.1.2
+    * open-uri 0.3.0
+    * open3 0.1.2
+    * openssl 3.1.0
+    * optparse 0.3.1
     * ostruct 0.5.5
-    * reline 0.3.1
-    * securerandom 0.2.0
+    * pathname 0.2.1
+    * pp 0.4.0
+    * pstore 0.1.2
+    * psych 5.0.1
+    * racc 1.6.2
+    * rdoc 6.5.0
+    * readline-ext 0.1.5
+    * reline 0.3.2
+    * resolv 0.2.2
+    * resolv-replace 0.1.1
+    * securerandom 0.2.2
+    * set 1.0.3
+    * stringio 3.0.4
+    * strscan 3.0.5
+    * syntax_suggest 1.0.2
+    * syslog 0.1.1
+    * tempfile 0.1.3
+    * time 0.2.1
+    * timeout 0.3.1
+    * tmpdir 0.1.3
+    * tsort 0.1.1
+    * un 0.2.1
+    * uri 0.12.0
+    * weakref 0.1.2
+    * win32ole 1.8.9
+    * yaml 0.2.1
+    * zlib 3.0.0
+
 *   The following bundled gems are updated.
-    * net-imap 0.2.3
-    * rbs 2.3.2
-    * typeprof 0.21.2
-    * debug 1.5.0
-*   The following default gems are now bundled gems.
+
+    * minitest 5.16.3
+    * power_assert 2.0.3
+    * test-unit 3.5.7
+    * net-ftp 0.2.0
+    * net-imap 0.3.4
+    * net-pop 0.1.2
+    * net-smtp 0.3.3
+    * rbs 2.8.2
+    * typeprof 0.21.3
+    * debug 1.7.1
+
+See GitHub releases like [GitHub Releases of Logger](https://github.com/ruby/logger/releases) or changelog for details of the default gems or bundled gems.
+
+## Supported platforms
+
+* WebAssembly/WASI is added. See [wasm/README.md] and [ruby.wasm] for more details. [[Feature #18462]]
 
 ## Compatibility issues
 
-Note: Excluding feature bug fixes.
+* `String#to_c` currently treat a sequence of underscores as an end of Complex
+  string. [[Bug #19087]]
+
+* Now `ENV.clone` raises `TypeError` as well as `ENV.dup` [[Bug #17767]]
 
 ### Removed constants
 
@@ -188,15 +592,77 @@ The following deprecated methods are removed.
   [[Feature #16131]]
 * `Kernel#trust`, `Kernel#untrust`, `Kernel#untrusted?`
   [[Feature #16131]]
+* `Method#public?`, `Method#private?`, `Method#protected?`,
+  `UnboundMethod#public?`, `UnboundMethod#private?`, `UnboundMethod#protected?`
+  [[Bug #18729]] [[Bug #18751]] [[Bug #18435]]
+
+### Source code incompatibility of extension libraries
+
+* Extension libraries provide PRNG, subclasses of Random, need updates.
+  See [PRNG update] below for more information. [[Bug #19100]]
+
+### Error printer
+
+* Ruby no longer escapes control characters and backslashes in an
+  error message. [[Feature #18367]]
+
+### Constant lookup when defining a class/module
+
+* When defining a class/module directly under the Object class by class/module
+  statement, if there is already a class/module defined by `Module#include`
+  with the same name, the statement was handled as "open class" in Ruby 3.1 or before.
+  Since Ruby 3.2, a new class is defined instead. [[Feature #18832]]
 
 ## Stdlib compatibility issues
 
-* `Psych` no longer bundles libyaml sources.
-  Users need to install the libyaml library themselves via the package
-  system.  [[Feature #18571]]
+* Psych no longer bundles libyaml sources.
+  And also Fiddle no longer bundles libffi sources.
+  Users need to install the libyaml/libffi library themselves via the package
+  manager like apt, yum, brew, etc.
+
+    Psych and fiddle supported the static build with specific version of libyaml
+    and libffi sources. You can build psych with libyaml-0.2.5 like this.
+
+    ```bash
+    $ ./configure --with-libyaml-source-dir=/path/to/libyaml-0.2.5
+    ```
+
+    And you can build fiddle with libffi-3.4.4 like this.
+
+    ```bash
+    $ ./configure --with-libffi-source-dir=/path/to/libffi-3.4.4
+    ```
+
+    [[Feature #18571]]
+
+* Check cookie name/path/domain characters in `CGI::Cookie`. [[CVE-2021-33621]]
+
+* `URI.parse` return empty string in host instead of nil. [[sec-156615]]
 
 ## C API updates
 
+### Updated C APIs
+
+The following APIs are updated.
+
+* PRNG update
+
+    `rb_random_interface_t` in ruby/random.h updated and versioned.
+    Extension libraries which use this interface and built for older
+    versions need to rebuild with adding `init_int32` function.
+
+### Added C APIs
+
+* `VALUE rb_hash_new_capa(long capa)` was added to created hashes with the desired capacity.
+* `rb_internal_thread_add_event_hook` and `rb_internal_thread_add_event_hook` were added to instrument threads scheduling.
+  The following events are available:
+    * `RUBY_INTERNAL_THREAD_EVENT_STARTED`
+    * `RUBY_INTERNAL_THREAD_EVENT_READY`
+    * `RUBY_INTERNAL_THREAD_EVENT_RESUMED`
+    * `RUBY_INTERNAL_THREAD_EVENT_SUSPENDED`
+    * `RUBY_INTERNAL_THREAD_EVENT_EXITED`
+* `rb_debug_inspector_current_depth` and `rb_debug_inspector_frame_depth` are added for debuggers.
+
 ### Removed C APIs
 
 The following deprecated APIs are removed.
@@ -206,48 +672,149 @@ The following deprecated APIs are removed.
 
 ## Implementation improvements
 
+* Fixed several race conditions in Kernel#autoload. [[Bug #18782]]
+* Cache invalidation for expressions referencing constants is now
+  more fine-grained. `RubyVM.stat(:global_constant_state)` was
+  removed because it was closely tied to the previous caching scheme
+  where setting any constant invalidates all caches in the system.
+  New keys, `:constant_cache_invalidations` and `:constant_cache_misses`,
+  were introduced to help with use cases for `:global_constant_state`.
+  [[Feature #18589]]
+* The cache-based optimization for Regexp matching is introduced.
+  [[Feature #19104]]
+* [Variable Width Allocation](https://shopify.engineering/ruby-variable-width-allocation)
+  is now enabled by default. [[Feature #18239]]
+* Added a new instance variable caching mechanism, called object shapes, which
+  improves inline cache hits for most objects and allows us to generate very
+  efficient JIT code. Objects whose instance variables are defined in a
+  consistent order will see the most performance benefits.
+  [[Feature #18776]]
+* Speed up marking instruction sequences by using a bitmap to find "markable"
+  objects.  This change results in faster major collections.
+  [[Feature #18875]]
+
 ## JIT
 
+### YJIT
+
+* YJIT is no longer experimental
+    * Has been tested on production workloads for over a year and proven to be quite stable.
+* YJIT now supports both x86-64 and arm64/aarch64 CPUs on Linux, MacOS, BSD and other UNIX platforms.
+    * This release brings support for Mac M1/M2, AWS Graviton and Raspberry Pi 4.
+* Building YJIT now requires Rust 1.58.0+. [[Feature #18481]]
+    * In order to ensure that CRuby is built with YJIT, please install `rustc` >= 1.58.0
+      before running `./configure`
+    * Please reach out to the YJIT team should you run into any issues.
+* Physical memory for JIT code is lazily allocated. Unlike Ruby 3.1,
+  the RSS of a Ruby process is minimized because virtual memory pages
+  allocated by `--yjit-exec-mem-size` will not be mapped to physical
+  memory pages until actually utilized by JIT code.
+* Introduce Code GC that frees all code pages when the memory consumption
+  by JIT code reaches `--yjit-exec-mem-size`.
+    * `RubyVM::YJIT.runtime_stats` returns Code GC metrics in addition to
+      existing `inline_code_size` and `outlined_code_size` keys:
+      `code_gc_count`, `live_page_count`, `freed_page_count`, and `freed_code_size`.
+* Most of the statistics produced by `RubyVM::YJIT.runtime_stats` are now available in release builds.
+    * Simply run ruby with `--yjit-stats` to compute and dump stats (incurs some run-time overhead).
+* YJIT is now optimized to take advantage of object shapes. [[Feature #18776]]
+* Take advantage of finer-grained constant invalidation to invalidate less code when defining new constants. [[Feature #18589]]
+* The default `--yjit-exec-mem-size` is changed to 64 (MiB).
+* The default `--yjit-call-threshold` is changed to 30.
+
 ### MJIT
 
-### YJIT: New experimental in-process JIT compiler
-
-## Static analysis
-
-### RBS
-
-### TypeProf
-
-## Debugger
-
-## error_highlight
-
-## IRB Autocomplete and Document Display
-
-## Miscellaneous changes
-
-[Feature #12005]: https://bugs.ruby-lang.org/issues/12005
-[Feature #12737]: https://bugs.ruby-lang.org/issues/12737
-[Feature #13110]: https://bugs.ruby-lang.org/issues/13110
-[Feature #14332]: https://bugs.ruby-lang.org/issues/14332
-[Feature #15231]: https://bugs.ruby-lang.org/issues/15231
-[Feature #15357]: https://bugs.ruby-lang.org/issues/15357
-[Bug #15928]:     https://bugs.ruby-lang.org/issues/15928
-[Feature #16131]: https://bugs.ruby-lang.org/issues/16131
-[Bug #16466]:     https://bugs.ruby-lang.org/issues/16466
-[Feature #16806]: https://bugs.ruby-lang.org/issues/16806
-[Bug #16889]:     https://bugs.ruby-lang.org/issues/16889
-[Bug #16908]:     https://bugs.ruby-lang.org/issues/16908
-[Feature #16989]: https://bugs.ruby-lang.org/issues/16989
-[Feature #17351]: https://bugs.ruby-lang.org/issues/17351
-[Feature #17391]: https://bugs.ruby-lang.org/issues/17391
-[Bug #17545]:     https://bugs.ruby-lang.org/issues/17545
-[Feature #17881]: https://bugs.ruby-lang.org/issues/17881
-[Feature #18037]: https://bugs.ruby-lang.org/issues/18037
-[Feature #18351]: https://bugs.ruby-lang.org/issues/18351
-[Bug #18487]:     https://bugs.ruby-lang.org/issues/18487
-[Feature #18571]: https://bugs.ruby-lang.org/issues/18571
-[Feature #18585]: https://bugs.ruby-lang.org/issues/18585
-[Feature #18598]: https://bugs.ruby-lang.org/issues/18598
-[Bug #18625]:     https://bugs.ruby-lang.org/issues/18625
-[Bug #18633]:     https://bugs.ruby-lang.org/issues/18633
+* The MJIT compiler is re-implemented in Ruby as `ruby_vm/mjit/compiler`.
+* MJIT compiler is executed under a forked Ruby process instead of
+  doing it in a native thread called MJIT worker. [[Feature #18968]]
+    * As a result, Microsoft Visual Studio (MSWIN) is no longer supported.
+* MinGW is no longer supported. [[Feature #18824]]
+* Rename `--mjit-min-calls` to `--mjit-call-threshold`.
+* Change default `--mjit-max-cache` back from 10000 to 100.
+
+[Feature #12005]:     https://bugs.ruby-lang.org/issues/12005
+[Feature #12084]:     https://bugs.ruby-lang.org/issues/12084
+[Feature #12655]:     https://bugs.ruby-lang.org/issues/12655
+[Feature #12737]:     https://bugs.ruby-lang.org/issues/12737
+[Feature #13110]:     https://bugs.ruby-lang.org/issues/13110
+[Feature #14332]:     https://bugs.ruby-lang.org/issues/14332
+[Feature #15231]:     https://bugs.ruby-lang.org/issues/15231
+[Feature #15357]:     https://bugs.ruby-lang.org/issues/15357
+[Bug #15928]:         https://bugs.ruby-lang.org/issues/15928
+[Feature #16122]:     https://bugs.ruby-lang.org/issues/16122
+[Feature #16131]:     https://bugs.ruby-lang.org/issues/16131
+[Bug #16466]:         https://bugs.ruby-lang.org/issues/16466
+[Feature #16663]:     https://bugs.ruby-lang.org/issues/16663
+[Feature #16806]:     https://bugs.ruby-lang.org/issues/16806
+[Bug #16889]:         https://bugs.ruby-lang.org/issues/16889
+[Bug #16908]:         https://bugs.ruby-lang.org/issues/16908
+[Feature #16989]:     https://bugs.ruby-lang.org/issues/16989
+[Feature #17351]:     https://bugs.ruby-lang.org/issues/17351
+[Feature #17391]:     https://bugs.ruby-lang.org/issues/17391
+[Bug #17545]:         https://bugs.ruby-lang.org/issues/17545
+[Bug #17767]:         https://bugs.ruby-lang.org/issues/17767
+[Feature #17837]:     https://bugs.ruby-lang.org/issues/17837
+[Feature #17881]:     https://bugs.ruby-lang.org/issues/17881
+[Feature #18033]:     https://bugs.ruby-lang.org/issues/18033
+[Feature #18159]:     https://bugs.ruby-lang.org/issues/18159
+[Feature #18239]:     https://bugs.ruby-lang.org/issues/18239#note-17
+[Feature #18351]:     https://bugs.ruby-lang.org/issues/18351
+[Feature #18367]:     https://bugs.ruby-lang.org/issues/18367
+[Bug #18435]:         https://bugs.ruby-lang.org/issues/18435
+[Feature #18462]:     https://bugs.ruby-lang.org/issues/18462
+[Feature #18481]:     https://bugs.ruby-lang.org/issues/18481
+[Bug #18487]:         https://bugs.ruby-lang.org/issues/18487
+[Feature #18564]:     https://bugs.ruby-lang.org/issues/18564
+[Feature #18571]:     https://bugs.ruby-lang.org/issues/18571
+[Feature #18585]:     https://bugs.ruby-lang.org/issues/18585
+[Feature #18589]:     https://bugs.ruby-lang.org/issues/18589
+[Feature #18595]:     https://bugs.ruby-lang.org/issues/18595
+[Feature #18598]:     https://bugs.ruby-lang.org/issues/18598
+[Bug #18625]:         https://bugs.ruby-lang.org/issues/18625
+[Feature #18630]:     https://bugs.ruby-lang.org/issues/18630
+[Bug #18633]:         https://bugs.ruby-lang.org/issues/18633
+[Feature #18639]:     https://bugs.ruby-lang.org/issues/18639
+[Feature #18685]:     https://bugs.ruby-lang.org/issues/18685
+[Bug #18729]:         https://bugs.ruby-lang.org/issues/18729
+[Bug #18751]:         https://bugs.ruby-lang.org/issues/18751
+[Feature #18774]:     https://bugs.ruby-lang.org/issues/18774
+[Feature #18776]:     https://bugs.ruby-lang.org/issues/18776
+[Bug #18782]:         https://bugs.ruby-lang.org/issues/18782
+[Feature #18788]:     https://bugs.ruby-lang.org/issues/18788
+[Feature #18798]:     https://bugs.ruby-lang.org/issues/18798
+[Feature #18809]:     https://bugs.ruby-lang.org/issues/18809
+[Feature #18821]:     https://bugs.ruby-lang.org/issues/18821
+[Feature #18822]:     https://bugs.ruby-lang.org/issues/18822
+[Feature #18824]:     https://bugs.ruby-lang.org/issues/18824
+[Feature #18832]:     https://bugs.ruby-lang.org/issues/18832
+[Feature #18875]:     https://bugs.ruby-lang.org/issues/18875
+[Feature #18925]:     https://bugs.ruby-lang.org/issues/18925
+[Feature #18944]:     https://bugs.ruby-lang.org/issues/18944
+[Feature #18949]:     https://bugs.ruby-lang.org/issues/18949
+[Feature #18968]:     https://bugs.ruby-lang.org/issues/18968
+[Feature #19008]:     https://bugs.ruby-lang.org/issues/19008
+[Feature #19013]:     https://bugs.ruby-lang.org/issues/19013
+[Feature #19026]:     https://bugs.ruby-lang.org/issues/19026
+[Feature #19036]:     https://bugs.ruby-lang.org/issues/19036
+[Feature #19060]:     https://bugs.ruby-lang.org/issues/19060
+[Feature #19070]:     https://bugs.ruby-lang.org/issues/19070
+[Feature #19071]:     https://bugs.ruby-lang.org/issues/19071
+[Feature #19078]:     https://bugs.ruby-lang.org/issues/19078
+[Bug #19087]:         https://bugs.ruby-lang.org/issues/19087
+[Bug #19100]:         https://bugs.ruby-lang.org/issues/19100
+[Feature #19104]:     https://bugs.ruby-lang.org/issues/19104
+[Feature #19135]:     https://bugs.ruby-lang.org/issues/19135
+[Feature #19138]:     https://bugs.ruby-lang.org/issues/19138
+[Feature #19194]:     https://bugs.ruby-lang.org/issues/19194
+[Molinillo]:          https://github.com/CocoaPods/Molinillo
+[PubGrub]:            https://github.com/jhawthorn/pub_grub
+[GH-net-protocol-14]: https://github.com/ruby/net-protocol/pull/14
+[GH-pathname-20]:     https://github.com/ruby/pathname/pull/20
+[GH-6791]:            https://github.com/ruby/ruby/pull/6791
+[GH-6868]:            https://github.com/ruby/ruby/pull/6868
+[GH-rubygems-4475]:   https://github.com/rubygems/rubygems/pull/4475
+[GH-rubygems-6149]:   https://github.com/rubygems/rubygems/pull/6149
+[GH-rubygems-6167]:   https://github.com/rubygems/rubygems/pull/6167
+[sec-156615]:         https://hackerone.com/reports/156615
+[CVE-2021-33621]:     https://www.ruby-lang.org/en/news/2022/11/22/http-response-splitting-in-cgi-cve-2021-33621/
+[wasm/README.md]:     https://github.com/ruby/ruby/blob/master/wasm/README.md
+[ruby.wasm]:          https://github.com/ruby/ruby.wasm
diff --git a/README.ja.md b/README.ja.md
index bb69c09055..93c0131690 100644
--- a/README.ja.md
+++ b/README.ja.md
@@ -4,7 +4,6 @@
 [![Actions Status: Windows](https://github.com/ruby/ruby/workflows/Windows/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"Windows")
 [![AppVeyor status](https://ci.appveyor.com/api/projects/status/0sy8rrxut4o0k960/branch/master?svg=true)](https://ci.appveyor.com/project/ruby/ruby/branch/master)
 [![Travis Status](https://app.travis-ci.com/ruby/ruby.svg?branch=master)](https://app.travis-ci.com/ruby/ruby)
-[![Cirrus Status](https://api.cirrus-ci.com/github/ruby/ruby.svg)](https://cirrus-ci.com/github/ruby/ruby/master)
 
 # Ruby��
 
diff --git a/README.md b/README.md
index 9b5a553ffb..c445448c71 100644
--- a/README.md
+++ b/README.md
@@ -4,9 +4,8 @@
 [![Actions Status: Windows](https://github.com/ruby/ruby/workflows/Windows/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"Windows")
 [![AppVeyor status](https://ci.appveyor.com/api/projects/status/0sy8rrxut4o0k960/branch/master?svg=true)](https://ci.appveyor.com/project/ruby/ruby/branch/master)
 [![Travis Status](https://app.travis-ci.com/ruby/ruby.svg?branch=master)](https://app.travis-ci.com/ruby/ruby)
-[![Cirrus Status](https://api.cirrus-ci.com/github/ruby/ruby.svg)](https://cirrus-ci.com/github/ruby/ruby/master)
 
-# What's Ruby
+# What is Ruby?
 
 Ruby is an interpreted object-oriented programming language often
 used for web development. It also offers many scripting features
@@ -15,28 +14,25 @@ It is simple, straightforward, and extensible.
 
 ## Features of Ruby
 
-*   Simple Syntax
-*   **Normal** Object-oriented Features (e.g. class, method calls)
-*   **Advanced** Object-oriented Features (e.g. mix-in, singleton-method)
-*   Operator Overloading
-*   Exception Handling
-*   Iterators and Closures
-*   Garbage Collection
-*   Dynamic Loading of Object Files (on some architectures)
-*   Highly Portable (works on many Unix-like/POSIX compatible platforms as
-    well as Windows, macOS, etc.) cf.
-    https://github.com/ruby/ruby/blob/master/doc/maintainers.rdoc#label-Platform+Maintainers
+* Simple Syntax
+* **Normal** Object-oriented Features (e.g. class, method calls)
+* **Advanced** Object-oriented Features (e.g. mix-in, singleton-method)
+* Operator Overloading
+* Exception Handling
+* Iterators and Closures
+* Garbage Collection
+* Dynamic Loading of Object Files (on some architectures)
+* Highly Portable (works on many Unix-like/POSIX compatible platforms as
+  well as Windows, macOS, etc.) cf.
+  https://github.com/ruby/ruby/blob/master/doc/maintainers.rdoc#label-Platform+Maintainers
 
-
-## How to get Ruby
+## How to get Ruby with Git
 
 For a complete list of ways to install Ruby, including using third-party tools
 like rvm, see:
 
 https://www.ruby-lang.org/en/downloads/
 
-### Git
-
 The mirror of the Ruby source tree can be checked out with the following command:
 
     $ git clone https://github.com/ruby/ruby.git
@@ -49,22 +45,19 @@ to see the list of branches:
 You may also want to use https://git.ruby-lang.org/ruby.git (actual master of Ruby source)
 if you are a committer.
 
-### Subversion
-
-Stable branches for older Ruby versions can be checked out with also the
-following command:
-
-    $ svn co https://svn.ruby-lang.org/repos/ruby/branches/ruby_2_6/ ruby
-
-Try the following command to see the list of branches:
-
-    $ svn ls https://svn.ruby-lang.org/repos/ruby/branches/
+## How to build
 
+see [Building Ruby](doc/contributing/building_ruby.md)
 
 ## Ruby home page
 
 https://www.ruby-lang.org/
 
+## Documentation
+
+- [English](https://docs.ruby-lang.org/en/master/index.html)
+- [Japanese](https://docs.ruby-lang.org/ja/master/index.html)
+
 ## Mailing list
 
 There is a mailing list to discuss Ruby. To subscribe to this list, please
@@ -76,108 +69,20 @@ in the mail body (not subject) to the address [ruby-talk-request@ruby-lang.org].
 
 [ruby-talk-request@ruby-lang.org]: mailto:ruby-talk-request@ruby-lang.org?subject=Join%20Ruby%20Mailing%20List&body=subscribe
 
-## Requirements to build from repository
-
-1. GNU or BSD make
-2. C99 compiler
-3. autoconf 2.67 or higher
-4. automake 1.15 or higher
-5. bison 2.3 or higher
-6. Ruby 2.2 or higher
-
-When building from a released version, only a C99 compiler and GNU or BSD make
-is required.
-
-## How to compile and install
-
-1.  If you want to use Microsoft Visual C++ to compile Ruby, read
-    [win32/README.win32](rdoc-ref:win32/README.win32) instead of this document.
-
-2.  Run `./autogen.sh` to generate configure, when you build the source checked
-    out from the Git repository.
-
-3.  Run `./configure`, which will generate `config.h` and `Makefile`.
-
-    Some C compiler flags may be added by default depending on your
-    environment. Specify `optflags=..` and `warnflags=..` as necessary to
-    override them.
-
-4.  Edit `include/ruby/defines.h` if you need. Usually this step will not be needed.
-
-5.  Optional: Remove comment mark(`#`) before the module names from `ext/Setup`.
-
-    This step is only necessary if you want to link modules statically.
-
-    If you don't want to compile dynamic extensions (probably on architectures
-    which do not allow dynamic loading), remove comment mark from the line
-    "`#option nodynamic`" in `ext/Setup`.
-
-    Usually this step will not be needed.
-
-6.  Run `make`.
-
-    * On Mac, set RUBY\_CODESIGN environment variable with a signing identity.
-      It uses the identity to sign `ruby` binary. See also codesign(1).
-
-7.  Optionally, run '`make check`' to check whether the compiled Ruby
-    interpreter works well. If you see the message "`check succeeded`", your
-    Ruby works as it should (hopefully).
-
-8.  Run '`make install`'.
-
-    This command will create the following directories and install files into
-    them.
-
-    *   `${DESTDIR}${prefix}/bin`
-    *   `${DESTDIR}${prefix}/include/ruby-${MAJOR}.${MINOR}.${TEENY}`
-    *   `${DESTDIR}${prefix}/include/ruby-${MAJOR}.${MINOR}.${TEENY}/${PLATFORM}`
-    *   `${DESTDIR}${prefix}/lib`
-    *   `${DESTDIR}${prefix}/lib/ruby`
-    *   `${DESTDIR}${prefix}/lib/ruby/${MAJOR}.${MINOR}.${TEENY}`
-    *   `${DESTDIR}${prefix}/lib/ruby/${MAJOR}.${MINOR}.${TEENY}/${PLATFORM}`
-    *   `${DESTDIR}${prefix}/lib/ruby/site_ruby`
-    *   `${DESTDIR}${prefix}/lib/ruby/site_ruby/${MAJOR}.${MINOR}.${TEENY}`
-    *   `${DESTDIR}${prefix}/lib/ruby/site_ruby/${MAJOR}.${MINOR}.${TEENY}/${PLATFORM}`
-    *   `${DESTDIR}${prefix}/lib/ruby/vendor_ruby`
-    *   `${DESTDIR}${prefix}/lib/ruby/vendor_ruby/${MAJOR}.${MINOR}.${TEENY}`
-    *   `${DESTDIR}${prefix}/lib/ruby/vendor_ruby/${MAJOR}.${MINOR}.${TEENY}/${PLATFORM}`
-    *   `${DESTDIR}${prefix}/lib/ruby/gems/${MAJOR}.${MINOR}.${TEENY}`
-    *   `${DESTDIR}${prefix}/share/man/man1`
-    *   `${DESTDIR}${prefix}/share/ri/${MAJOR}.${MINOR}.${TEENY}/system`
-
-
-    If Ruby's API version is '*x.y.z*', the `${MAJOR}` is '*x*', the
-    `${MINOR}` is '*y*', and the `${TEENY}` is '*z*'.
-
-    **NOTE**: teeny of the API version may be different from one of Ruby's
-    program version
-
-    You may have to be a super user to install Ruby.
-
-If you fail to compile Ruby, please send the detailed error report with the
-error log and machine/OS type, to help others.
-
-Some extension libraries may not get compiled because of lack of necessary
-external libraries and/or headers, then you will need to run '`make distclean-ext`'
-to remove old configuration after installing them in such case.
-
 ## Copying
 
 See the file [COPYING](rdoc-ref:COPYING).
 
 ## Feedback
 
-Questions about the Ruby language can be asked on the [Ruby-Talk] mailing list
+Questions about the Ruby language can be asked on the [Ruby-Talk](https://www.ruby-lang.org/en/community/mailing-lists) mailing list
 or on websites like https://stackoverflow.com.
 
-Bugs should be reported at https://bugs.ruby-lang.org. Read [HowToReport] for more information.
-
-[Ruby-Talk]: https://www.ruby-lang.org/en/community/mailing-lists
-[HowToReport]: https://bugs.ruby-lang.org/projects/ruby/wiki/HowToReport
+Bugs should be reported at https://bugs.ruby-lang.org. Read ["Reporting Issues"](https://docs.ruby-lang.org/en/master/contributing/reporting_issues_md.html) for more information.
 
 ## Contributing
 
-See the file [CONTRIBUTING.md](rdoc-ref:CONTRIBUTING)
+See ["Contributing to Ruby"](https://docs.ruby-lang.org/en/master/contributing_md.html), which includes setup and build instructions.
 
 ## The Author
 
diff --git a/addr2line.c b/addr2line.c
index f660be9129..e5f25293e2 100644
--- a/addr2line.c
+++ b/addr2line.c
@@ -159,12 +159,15 @@ typedef struct obj_info {
     struct dwarf_section debug_info;
     struct dwarf_section debug_line;
     struct dwarf_section debug_ranges;
+    struct dwarf_section debug_str_offsets;
+    struct dwarf_section debug_addr;
     struct dwarf_section debug_rnglists;
     struct dwarf_section debug_str;
+    struct dwarf_section debug_line_str;
     struct obj_info *next;
 } obj_info_t;
 
-#define DWARF_SECTION_COUNT 6
+#define DWARF_SECTION_COUNT 9
 
 static struct dwarf_section *
 obj_dwarf_section_at(obj_info_t *obj, int n)
@@ -174,8 +177,11 @@ obj_dwarf_section_at(obj_info_t *obj, int n)
         &obj->debug_info,
         &obj->debug_line,
         &obj->debug_ranges,
+        &obj->debug_str_offsets,
+        &obj->debug_addr,
         &obj->debug_rnglists,
-        &obj->debug_str
+        &obj->debug_str,
+        &obj->debug_line_str
     };
     if (n < 0 || DWARF_SECTION_COUNT <= n) {
         abort();
@@ -248,39 +254,51 @@ get_nth_dirname(unsigned long dir, const char *p)
     return p;
 }
 
+static const char *parse_ver5_debug_line_header(const char *p, int idx, uint8_t format, obj_info_t *obj, const char **out_path, uint64_t *out_directory_index);
+
 static void
-fill_filename(int file, const char *include_directories, const char *filenames, line_info_t *line, obj_info_t *obj)
+fill_filename(int file, uint8_t format, uint16_t version, const char *include_directories, const char *filenames, line_info_t *line, obj_info_t *obj)
 {
     int i;
     const char *p = filenames;
     const char *filename;
     unsigned long dir;
-    for (i = 1; i <= file; i++) {
-	filename = p;
-	if (!*p) {
-	    /* Need to output binary file name? */
-	    kprintf("Unexpected file number %d in %s at %tx\n",
-		    file, binary_filename, filenames - obj->mapped);
-	    return;
-	}
-	while (*p) p++;
-	p++;
-	dir = uleb128(&p);
-	/* last modified. */
-	uleb128(&p);
-	/* size of the file. */
-	uleb128(&p);
-
-	if (i == file) {
-	    line->filename = filename;
-	    line->dirname = get_nth_dirname(dir, include_directories);
-	}
+    if (version >= 5) {
+        const char *path;
+        uint64_t directory_index = -1;
+        parse_ver5_debug_line_header(filenames, file, format, obj, &path, &directory_index);
+        line->filename = path;
+        parse_ver5_debug_line_header(include_directories, (int)directory_index, format, obj, &path, NULL);
+        line->dirname = path;
+    }
+    else {
+        for (i = 1; i <= file; i++) {
+            filename = p;
+            if (!*p) {
+                /* Need to output binary file name? */
+                kprintf("Unexpected file number %d in %s at %tx\n",
+                        file, binary_filename, filenames - obj->mapped);
+                return;
+            }
+            while (*p) p++;
+            p++;
+            dir = uleb128(&p);
+            /* last modified. */
+            uleb128(&p);
+            /* size of the file. */
+            uleb128(&p);
+
+            if (i == file) {
+                line->filename = filename;
+                line->dirname = get_nth_dirname(dir, include_directories);
+            }
+        }
     }
 }
 
 static void
 fill_line(int num_traces, void **traces, uintptr_t addr, int file, int line,
-	  const char *include_directories, const char *filenames,
+	  uint8_t format, uint16_t version, const char *include_directories, const char *filenames,
 	  obj_info_t *obj, line_info_t *lines, int offset)
 {
     int i;
@@ -290,7 +308,7 @@ fill_line(int num_traces, void **traces, uintptr_t addr, int file, int line,
 	/* We assume one line code doesn't result >100 bytes of native code.
        We may want more reliable way eventually... */
 	if (addr < a && a < addr + 100) {
-	    fill_filename(file, include_directories, filenames, &lines[i], obj);
+	    fill_filename(file, format, version, include_directories, filenames, &lines[i], obj);
 	    lines[i].line = line;
 	}
     }
@@ -315,7 +333,7 @@ struct LineNumberProgramHeader {
 };
 
 static int
-parse_debug_line_header(const char **pp, struct LineNumberProgramHeader *header)
+parse_debug_line_header(obj_info_t *obj, const char **pp, struct LineNumberProgramHeader *header)
 {
     const char *p = *pp;
     header->unit_length = *(uint32_t *)p;
@@ -332,7 +350,13 @@ parse_debug_line_header(const char **pp, struct LineNumberProgramHeader *header)
 
     header->version = *(uint16_t *)p;
     p += sizeof(uint16_t);
-    if (header->version > 4) return -1;
+    if (header->version > 5) return -1;
+
+    if (header->version >= 5) {
+        /* address_size = *(uint8_t *)p++; */
+        /* segment_selector_size = *(uint8_t *)p++; */
+        p += 2;
+    }
 
     header->header_length = header->format == 4 ? *(uint32_t *)p : *(uint64_t *)p;
     p += header->format;
@@ -353,20 +377,27 @@ parse_debug_line_header(const char **pp, struct LineNumberProgramHeader *header)
     /* header->standard_opcode_lengths = (uint8_t *)p - 1; */
     p += header->opcode_base - 1;
 
-    header->include_directories = p;
+    if (header->version >= 5) {
+        header->include_directories = p;
+        p = parse_ver5_debug_line_header(p, -1, header->format, obj, NULL, NULL);
+        header->filenames = p;
+    }
+    else {
+        header->include_directories = p;
 
-    /* temporary measure for compress-debug-sections */
-    if (p >= header->cu_end) return -1;
+        /* temporary measure for compress-debug-sections */
+        if (p >= header->cu_end) return -1;
 
-    /* skip include directories */
-    while (*p) {
-	p = memchr(p, '\0', header->cu_end - p);
-	if (!p) return -1;
-	p++;
-    }
-    p++;
+        /* skip include directories */
+        while (*p) {
+            p = memchr(p, '\0', header->cu_end - p);
+            if (!p) return -1;
+            p++;
+        }
+        p++;
 
-    header->filenames = p;
+        header->filenames = p;
+    }
 
     *pp = header->cu_start;
 
@@ -392,13 +423,15 @@ parse_debug_line_cu(int num_traces, void **traces, const char **debug_line,
     /* int epilogue_begin = 0; */
     /* unsigned int isa = 0; */
 
-    if (parse_debug_line_header(&p, &header))
+    if (parse_debug_line_header(obj, &p, &header))
         return -1;
     is_stmt = header.default_is_stmt;
 
 #define FILL_LINE()						    \
     do {							    \
 	fill_line(num_traces, traces, addr, file, line,		    \
+                  header.format,                                    \
+                  header.version,                                   \
                   header.include_directories,                       \
                   header.filenames,                                 \
 		  obj, lines, offset);				    \
@@ -827,16 +860,23 @@ enum {
     VAL_cstr = 1,
     VAL_data = 2,
     VAL_uint = 3,
-    VAL_int = 4
+    VAL_int = 4,
+    VAL_addr = 5
 };
 
 # define ABBREV_TABLE_SIZE 256
 typedef struct {
     obj_info_t *obj;
     const char *file;
+    uint8_t current_version;
     const char *current_cu;
     uint64_t current_low_pc;
+    uint64_t current_str_offsets_base;
+    uint64_t current_addr_base;
+    uint64_t current_rnglists_base;
     const char *debug_line_cu_end;
+    uint8_t debug_line_format;
+    uint16_t debug_line_version;
     const char *debug_line_files;
     const char *debug_line_directories;
     const char *p;
@@ -861,6 +901,7 @@ typedef struct {
         const char *ptr;
         uint64_t uint64;
         int64_t int64;
+        uint64_t addr_idx;
     } as;
     uint64_t off;
     uint64_t at;
@@ -869,8 +910,11 @@ typedef struct {
     int type;
 } DebugInfoValue;
 
-/* TODO: Big Endian */
+#if defined(WORDS_BIGENDIAN)
+#define MERGE_2INTS(a,b,sz) (((uint64_t)(a)<<sz)|(b))
+#else
 #define MERGE_2INTS(a,b,sz) (((uint64_t)(b)<<sz)|(a))
+#endif
 
 static uint16_t
 get_uint16(const uint8_t *p)
@@ -973,6 +1017,9 @@ debug_info_reader_init(DebugInfoReader *reader, obj_info_t *obj)
     reader->pend = obj->debug_info.ptr + obj->debug_info.size;
     reader->debug_line_cu_end = obj->debug_line.ptr;
     reader->current_low_pc = 0;
+    reader->current_str_offsets_base = 0;
+    reader->current_addr_base = 0;
+    reader->current_rnglists_base = 0;
 }
 
 static void
@@ -1017,10 +1064,12 @@ di_read_debug_line_cu(DebugInfoReader *reader)
     struct LineNumberProgramHeader header;
 
     p = (const char *)reader->debug_line_cu_end;
-    if (parse_debug_line_header(&p, &header))
+    if (parse_debug_line_header(reader->obj, &p, &header))
         return -1;
 
     reader->debug_line_cu_end = (char *)header.cu_end;
+    reader->debug_line_format = header.format;
+    reader->debug_line_version = header.version;
     reader->debug_line_directories = (char *)header.include_directories;
     reader->debug_line_files = (char *)header.filenames;
 
@@ -1028,6 +1077,13 @@ di_read_debug_line_cu(DebugInfoReader *reader)
 }
 
 static void
+set_addr_idx_value(DebugInfoValue *v, uint64_t n)
+{
+    v->as.addr_idx = n;
+    v->type = VAL_addr;
+}
+
+static void
 set_uint_value(DebugInfoValue *v, uint64_t n)
 {
     v->as.uint64 = n;
@@ -1074,19 +1130,39 @@ get_cstr_value(DebugInfoValue *v)
     }
 }
 
+static const char *
+resolve_strx(DebugInfoReader *reader, uint64_t idx)
+{
+    const char *p = reader->obj->debug_str_offsets.ptr + reader->current_str_offsets_base;
+    uint64_t off;
+    if (reader->format == 4) {
+        off = ((uint32_t *)p)[idx];
+    }
+    else {
+        off = ((uint64_t *)p)[idx];
+    }
+    return reader->obj->debug_str.ptr + off;
+}
+
+static void
+debug_info_reader_read_addr_value(DebugInfoReader *reader, DebugInfoValue *v)
+{
+    if (reader->address_size == 4) {
+        set_uint_value(v, read_uint32(&reader->p));
+    } else if (reader->address_size == 8) {
+        set_uint_value(v, read_uint64(&reader->p));
+    } else {
+        fprintf(stderr,"unknown address_size:%d", reader->address_size);
+        abort();
+    }
+}
+
 static void
 debug_info_reader_read_value(DebugInfoReader *reader, uint64_t form, DebugInfoValue *v)
 {
     switch (form) {
       case DW_FORM_addr:
-        if (reader->address_size == 4) {
-            set_uint_value(v, read_uint32(&reader->p));
-        } else if (reader->address_size == 8) {
-            set_uint_value(v, read_uint64(&reader->p));
-        } else {
-            fprintf(stderr,"unknown address_size:%d", reader->address_size);
-            abort();
-        }
+        debug_info_reader_read_addr_value(reader, v);
         break;
       case DW_FORM_block2:
         v->size = read_uint16(&reader->p);
@@ -1138,13 +1214,19 @@ debug_info_reader_read_value(DebugInfoReader *reader, uint64_t form, DebugInfoVa
         set_uint_value(v, read_uleb128(reader));
         break;
       case DW_FORM_ref_addr:
-        if (reader->format == 4) {
-            set_uint_value(v, read_uint32(&reader->p));
-        } else if (reader->format == 8) {
-            set_uint_value(v, read_uint64(&reader->p));
+        if (reader->current_version <= 2) {
+            // DWARF Version 2 specifies that references have
+            // the same size as an address on the target system
+            debug_info_reader_read_addr_value(reader, v);
         } else {
-            fprintf(stderr,"unknown format:%d", reader->format);
-            abort();
+            if (reader->format == 4) {
+                set_uint_value(v, read_uint32(&reader->p));
+            } else if (reader->format == 8) {
+                set_uint_value(v, read_uint64(&reader->p));
+            } else {
+                fprintf(stderr,"unknown format:%d", reader->format);
+                abort();
+            }
         }
         break;
       case DW_FORM_ref1:
@@ -1186,11 +1268,10 @@ debug_info_reader_read_value(DebugInfoReader *reader, uint64_t form, DebugInfoVa
         set_uint_value(v, 1);
         break;
       case DW_FORM_strx:
-        set_uint_value(v, uleb128(&reader->p));
+        set_cstr_value(v, resolve_strx(reader, uleb128(&reader->p)));
         break;
       case DW_FORM_addrx:
-        /* TODO: read .debug_addr */
-        set_uint_value(v, uleb128(&reader->p));
+        set_addr_idx_value(v, uleb128(&reader->p));
         break;
       case DW_FORM_ref_sup4:
         set_uint_value(v, read_uint32(&reader->p));
@@ -1205,8 +1286,7 @@ debug_info_reader_read_value(DebugInfoReader *reader, uint64_t form, DebugInfoVa
         reader->p += v->size;
         break;
       case DW_FORM_line_strp:
-        set_uint_value(v, read_uint(reader));
-        /* *p = reader->file + reader->line->sh_offset + ret; */
+        set_cstrp_value(v, reader->obj->debug_line_str.ptr, read_uint(reader));
         break;
       case DW_FORM_ref_sig8:
         set_uint_value(v, read_uint64(&reader->p));
@@ -1224,28 +1304,28 @@ debug_info_reader_read_value(DebugInfoReader *reader, uint64_t form, DebugInfoVa
         set_uint_value(v, read_uint64(&reader->p));
         break;
       case DW_FORM_strx1:
-        set_uint_value(v, read_uint8(&reader->p));
+        set_cstr_value(v, resolve_strx(reader, read_uint8(&reader->p)));
         break;
       case DW_FORM_strx2:
-        set_uint_value(v, read_uint16(&reader->p));
+        set_cstr_value(v, resolve_strx(reader, read_uint16(&reader->p)));
         break;
       case DW_FORM_strx3:
-        set_uint_value(v, read_uint24(&reader->p));
+        set_cstr_value(v, resolve_strx(reader, read_uint24(&reader->p)));
         break;
       case DW_FORM_strx4:
-        set_uint_value(v, read_uint32(&reader->p));
+        set_cstr_value(v, resolve_strx(reader, read_uint32(&reader->p)));
         break;
       case DW_FORM_addrx1:
-        set_uint_value(v, read_uint8(&reader->p));
+        set_addr_idx_value(v, read_uint8(&reader->p));
         break;
       case DW_FORM_addrx2:
-        set_uint_value(v, read_uint16(&reader->p));
+        set_addr_idx_value(v, read_uint16(&reader->p));
         break;
       case DW_FORM_addrx3:
-        set_uint_value(v, read_uint24(&reader->p));
+        set_addr_idx_value(v, read_uint24(&reader->p));
         break;
       case DW_FORM_addrx4:
-        set_uint_value(v, read_uint32(&reader->p));
+        set_addr_idx_value(v, read_uint32(&reader->p));
         break;
       case 0:
         goto fail;
@@ -1292,7 +1372,7 @@ hexdump0(const unsigned char *p, size_t n)
     for (i=0; i < n; i++){
         switch (i & 15) {
           case 0:
-            fprintf(stderr, "%02zd: %02X ", i/16, p[i]);
+            fprintf(stderr, "%02" PRIdSIZE ": %02X ", i/16, p[i]);
             break;
           case 15:
             fprintf(stderr, "%02X\n", p[i]);
@@ -1313,16 +1393,16 @@ div_inspect(DebugInfoValue *v)
 {
     switch (v->type) {
       case VAL_uint:
-        fprintf(stderr,"%d: type:%d size:%zx v:%"PRIx64"\n",__LINE__,v->type,v->size,v->as.uint64);
+        fprintf(stderr,"%d: type:%d size:%" PRIxSIZE " v:%"PRIx64"\n",__LINE__,v->type,v->size,v->as.uint64);
         break;
       case VAL_int:
-        fprintf(stderr,"%d: type:%d size:%zx v:%"PRId64"\n",__LINE__,v->type,v->size,(int64_t)v->as.uint64);
+        fprintf(stderr,"%d: type:%d size:%" PRIxSIZE " v:%"PRId64"\n",__LINE__,v->type,v->size,(int64_t)v->as.uint64);
         break;
       case VAL_cstr:
-        fprintf(stderr,"%d: type:%d size:%zx v:'%s'\n",__LINE__,v->type,v->size,v->as.ptr);
+        fprintf(stderr,"%d: type:%d size:%" PRIxSIZE " v:'%s'\n",__LINE__,v->type,v->size,v->as.ptr);
         break;
       case VAL_data:
-        fprintf(stderr,"%d: type:%d size:%zx v:\n",__LINE__,v->type,v->size);
+        fprintf(stderr,"%d: type:%d size:%" PRIxSIZE " v:\n",__LINE__,v->type,v->size);
         hexdump(v->as.ptr, 16);
         break;
     }
@@ -1373,6 +1453,76 @@ di_skip_records(DebugInfoReader *reader)
     }
 }
 
+typedef struct addr_header {
+    const char *ptr;
+    uint64_t unit_length;
+    uint8_t format;
+    uint8_t address_size;
+    /* uint8_t segment_selector_size; */
+} addr_header_t;
+
+static void
+addr_header_init(obj_info_t *obj, addr_header_t *header) {
+    const char *p = obj->debug_addr.ptr;
+
+    header->ptr = p;
+
+    if (!p) return;
+
+    header->unit_length = *(uint32_t *)p;
+    p += sizeof(uint32_t);
+
+    header->format = 4;
+    if (header->unit_length == 0xffffffff) {
+        header->unit_length = *(uint64_t *)p;
+        p += sizeof(uint64_t);
+        header->format = 8;
+    }
+
+    p += 2; /* version */
+    header->address_size = *p++;
+    p++; /* segment_selector_size */
+}
+
+static uint64_t
+read_addr(addr_header_t *header, uint64_t addr_base, uint64_t idx) {
+    if (header->address_size == 4) {
+        return ((uint32_t*)(header->ptr + addr_base))[idx];
+    }
+    else {
+        return ((uint64_t*)(header->ptr + addr_base))[idx];
+    }
+}
+
+typedef struct rnglists_header {
+    uint64_t unit_length;
+    uint8_t format;
+    uint8_t address_size;
+    uint32_t offset_entry_count;
+} rnglists_header_t;
+
+static void
+rnglists_header_init(obj_info_t *obj, rnglists_header_t *header) {
+    const char *p = obj->debug_rnglists.ptr;
+
+    if (!p) return;
+
+    header->unit_length = *(uint32_t *)p;
+    p += sizeof(uint32_t);
+
+    header->format = 4;
+    if (header->unit_length == 0xffffffff) {
+        header->unit_length = *(uint64_t *)p;
+        p += sizeof(uint64_t);
+        header->format = 8;
+    }
+
+    p += 2; /* version */
+    header->address_size = *p++;
+    p++; /* segment_selector_size */
+    header->offset_entry_count = *(uint32_t *)p;
+}
+
 typedef struct {
     uint64_t low_pc;
     uint64_t high_pc;
@@ -1383,24 +1533,31 @@ typedef struct {
 } ranges_t;
 
 static void
-ranges_set(ranges_t *ptr, DebugInfoValue *v)
+ranges_set(ranges_t *ptr, DebugInfoValue *v, addr_header_t *addr_header, uint64_t addr_base)
 {
+    uint64_t n = 0;
+    if (v->type == VAL_uint) {
+        n = v->as.uint64;
+    }
+    else if (v->type == VAL_addr) {
+        n = read_addr(addr_header, addr_base, v->as.addr_idx);
+    }
     switch (v->at) {
       case DW_AT_low_pc:
-        ptr->low_pc = v->as.uint64;
+        ptr->low_pc = n;
         ptr->low_pc_set = true;
         break;
       case DW_AT_high_pc:
         if (v->form == DW_FORM_addr) {
-            ptr->high_pc = v->as.uint64;
+            ptr->high_pc = n;
         }
         else {
-            ptr->high_pc = ptr->low_pc + v->as.uint64;
+            ptr->high_pc = ptr->low_pc + n;
         }
         ptr->high_pc_set = true;
         break;
       case DW_AT_ranges:
-        ptr->ranges = v->as.uint64;
+        ptr->ranges = n;
         ptr->ranges_set = true;
         break;
     }
@@ -1422,7 +1579,7 @@ read_dw_form_addr(DebugInfoReader *reader, const char **ptr)
 }
 
 static uintptr_t
-ranges_include(DebugInfoReader *reader, ranges_t *ptr, uint64_t addr)
+ranges_include(DebugInfoReader *reader, ranges_t *ptr, uint64_t addr, rnglists_header_t *rnglists_header)
 {
     if (ptr->high_pc_set) {
         if (ptr->ranges_set || !ptr->low_pc_set) {
@@ -1437,8 +1594,21 @@ ranges_include(DebugInfoReader *reader, ranges_t *ptr, uint64_t addr)
         const char *p;
         uint64_t base = ptr->low_pc_set ? ptr->low_pc : reader->current_low_pc;
         bool base_valid = true;
-        if (reader->obj->debug_rnglists.ptr) {
-            p = reader->obj->debug_rnglists.ptr + ptr->ranges;
+        if (reader->current_version >= 5) {
+            if (rnglists_header->offset_entry_count == 0) {
+                // DW_FORM_sec_offset
+                p = reader->obj->debug_rnglists.ptr + ptr->ranges + reader->current_rnglists_base;
+            }
+            else {
+                // DW_FORM_rnglistx
+                const char *offset_array = reader->obj->debug_rnglists.ptr + reader->current_rnglists_base;
+                if (rnglists_header->format == 4) {
+                    p = offset_array + ((uint32_t *)offset_array)[ptr->ranges];
+                }
+                else {
+                    p = offset_array + ((uint64_t *)offset_array)[ptr->ranges];
+                }
+            }
             for (;;) {
                 uint8_t rle = read_uint8(&p);
                 uintptr_t from = 0, to = 0;
@@ -1548,6 +1718,7 @@ di_read_cu(DebugInfoReader *reader)
     }
     reader->cu_end = reader->p + unit_length;
     version = read_uint16(&reader->p);
+    reader->current_version = version;
     if (version > 5) {
         return -1;
     }
@@ -1580,16 +1751,45 @@ di_read_cu(DebugInfoReader *reader)
             break;
         }
 
+        reader->current_str_offsets_base = 0;
+        reader->current_addr_base = 0;
+        reader->current_rnglists_base = 0;
+
+        DebugInfoValue low_pc = {{}};
         /* enumerate abbrev */
         for (;;) {
             DebugInfoValue v = {{}};
             if (!di_read_record(reader, &v)) break;
             switch (v.at) {
               case DW_AT_low_pc:
-                reader->current_low_pc = v.as.uint64;
+                // clang may output DW_AT_addr_base after DW_AT_low_pc.
+                // We need to resolve the DW_FORM_addr* after DW_AT_addr_base is parsed.
+                low_pc = v;
+                break;
+              case DW_AT_str_offsets_base:
+                reader->current_str_offsets_base = v.as.uint64;
+                break;
+              case DW_AT_addr_base:
+                reader->current_addr_base = v.as.uint64;
+                break;
+              case DW_AT_rnglists_base:
+                reader->current_rnglists_base = v.as.uint64;
                 break;
             }
         }
+        // Resolve the DW_FORM_addr of DW_AT_low_pc
+        switch (low_pc.type) {
+            case VAL_uint:
+                reader->current_low_pc = low_pc.as.uint64;
+                break;
+            case VAL_addr:
+                {
+                    addr_header_t header;
+                    addr_header_init(reader->obj, &header);
+                    reader->current_low_pc = read_addr(&header, reader->current_addr_base, low_pc.as.addr_idx);
+                }
+                break;
+        }
     } while (0);
 #endif
     return 0;
@@ -1643,6 +1843,13 @@ read_abstract_origin(DebugInfoReader *reader, uint64_t form, uint64_t abstract_o
 static void
 debug_info_read(DebugInfoReader *reader, int num_traces, void **traces,
          line_info_t *lines, int offset) {
+
+    addr_header_t addr_header = {};
+    addr_header_init(reader->obj, &addr_header);
+
+    rnglists_header_t rnglists_header = {};
+    rnglists_header_init(reader->obj, &rnglists_header);
+
     while (reader->p < reader->cu_end) {
         DIE die;
         ranges_t ranges = {};
@@ -1669,7 +1876,7 @@ debug_info_read(DebugInfoReader *reader, int num_traces, void **traces,
                 line.sname = get_cstr_value(&v);
                 break;
               case DW_AT_call_file:
-                fill_filename((int)v.as.uint64, reader->debug_line_directories, reader->debug_line_files, &line, reader->obj);
+                fill_filename((int)v.as.uint64, reader->debug_line_format, reader->debug_line_version, reader->debug_line_directories, reader->debug_line_files, &line, reader->obj);
                 break;
               case DW_AT_call_line:
                 line.line = (int)v.as.uint64;
@@ -1677,7 +1884,7 @@ debug_info_read(DebugInfoReader *reader, int num_traces, void **traces,
               case DW_AT_low_pc:
               case DW_AT_high_pc:
               case DW_AT_ranges:
-                ranges_set(&ranges, &v);
+                ranges_set(&ranges, &v, &addr_header, reader->current_addr_base);
                 break;
               case DW_AT_declaration:
                 goto skip_die;
@@ -1694,9 +1901,9 @@ debug_info_read(DebugInfoReader *reader, int num_traces, void **traces,
         for (int i=offset; i < num_traces; i++) {
             uintptr_t addr = (uintptr_t)traces[i];
             uintptr_t offset = addr - reader->obj->base_addr + reader->obj->vmaddr;
-            uintptr_t saddr = ranges_include(reader, &ranges, offset);
+            uintptr_t saddr = ranges_include(reader, &ranges, offset, &rnglists_header);
             if (saddr) {
-                /* fprintf(stderr, "%d:%tx: %d %lx->%lx %x %s: %s/%s %d %s %s %s\n",__LINE__,die.pos, i,addr,offset, die.tag,line.sname,line.dirname,line.filename,line.line,reader->obj->path,line.sname,lines[i].sname); */
+                /* fprintf(stdout, "%d:%tx: %d %lx->%lx %x %s: %s/%s %d %s %s %s\n",__LINE__,die.pos, i,addr,offset, die.tag,line.sname,line.dirname,line.filename,line.line,reader->obj->path,line.sname,lines[i].sname); */
                 if (lines[i].sname) {
                     line_info_t *lp = malloc(sizeof(line_info_t));
                     memcpy(lp, &lines[i], sizeof(line_info_t));
@@ -1715,6 +1922,54 @@ debug_info_read(DebugInfoReader *reader, int num_traces, void **traces,
     }
 }
 
+// This function parses the following attributes of Line Number Program Header in DWARF 5:
+//
+// * directory_entry_format_count
+// * directory_entry_format
+// * directories_count
+// * directories
+//
+// or
+//
+// * file_name_entry_format_count
+// * file_name_entry_format
+// * file_names_count
+// * file_names
+//
+// It records DW_LNCT_path and DW_LNCT_directory_index at the index "idx".
+static const char *
+parse_ver5_debug_line_header(const char *p, int idx, uint8_t format, obj_info_t *obj, const char **out_path, uint64_t *out_directory_index) {
+    int i, j;
+    int entry_format_count = *(uint8_t *)p++;
+    const char *entry_format = p;
+
+    /* skip the part of entry_format */
+    for (i = 0; i < entry_format_count * 2; i++) uleb128(&p);
+
+    int entry_count = (int)uleb128(&p);
+
+    DebugInfoReader reader;
+    debug_info_reader_init(&reader, obj);
+    reader.format = format;
+    reader.p = p;
+    for (j = 0; j < entry_count; j++) {
+        const char *format = entry_format;
+        for (i = 0; i < entry_format_count; i++) {
+            DebugInfoValue v = {{}};
+            unsigned long dw_lnct = uleb128(&format);
+            unsigned long dw_form = uleb128(&format);
+            debug_info_reader_read_value(&reader, dw_form, &v);
+            if (dw_lnct == 1 /* DW_LNCT_path */ && v.type == VAL_cstr && out_path)
+                *out_path = v.as.ptr + v.off;
+            if (dw_lnct == 2 /* DW_LNCT_directory_index */ && v.type == VAL_uint && out_directory_index)
+                *out_directory_index = v.as.uint64;
+        }
+        if (j == idx) return 0;
+    }
+
+    return reader.p;
+}
+
 #ifdef USE_ELF
 static unsigned long
 uncompress_debug_section(ElfW(Shdr) *shdr, char *file, char **ptr)
@@ -1843,8 +2098,11 @@ fill_lines(int num_traces, void **traces, int check_debuglink,
                     ".debug_info",
                     ".debug_line",
                     ".debug_ranges",
+                    ".debug_str_offsets",
+                    ".debug_addr",
                     ".debug_rnglists",
-                    ".debug_str"
+                    ".debug_str",
+                    ".debug_line_str"
                 };
 
                 for (j=0; j < DWARF_SECTION_COUNT; j++) {
@@ -2100,8 +2358,11 @@ found_mach_header:
                     "__debug_info",
                     "__debug_line",
                     "__debug_ranges",
+                    "__debug_str_offsets",
+                    "__debug_addr",
                     "__debug_rnglists",
-                    "__debug_str"
+                    "__debug_str",
+                    "__debug_line_str",
                 };
                 struct LP(segment_command) *scmd = (struct LP(segment_command) *)lcmd;
                 if (strcmp(scmd->segname, "__TEXT") == 0) {
@@ -2257,9 +2518,12 @@ print_line0(line_info_t *line, void *address)
     else if (!line->path) {
         kprintf("[0x%"PRIxPTR"]\n", addr);
     }
-    else if (!line->saddr || !line->sname) {
+    else if (!line->sname) {
         kprintf("%s(0x%"PRIxPTR") [0x%"PRIxPTR"]\n", line->path, addr-line->base_addr, addr);
     }
+    else if (!line->saddr) {
+        kprintf("%s(%s) [0x%"PRIxPTR"]\n", line->path, line->sname, addr);
+    }
     else if (line->line <= 0) {
         kprintf("%s(%s+0x%"PRIxPTR") [0x%"PRIxPTR"]\n", line->path, line->sname,
                 d, addr);
@@ -2296,6 +2560,7 @@ rb_dump_backtrace_with_lines(int num_traces, void **traces)
     obj_info_t *obj = NULL;
     /* 2 is NULL + main executable */
     void **dladdr_fbases = (void **)calloc(num_traces+2, sizeof(void *));
+
 #ifdef HAVE_MAIN_EXE_PATH
     char *main_path = NULL; /* used on printing backtrace */
     ssize_t len;
@@ -2326,8 +2591,8 @@ rb_dump_backtrace_with_lines(int num_traces, void **traces)
 	    /* if the binary is strip-ed, this may effect */
 	    for (p=dladdr_fbases; *p; p++) {
 		if (*p == info.dli_fbase) {
-		    lines[i].path = info.dli_fname;
-		    lines[i].sname = info.dli_sname;
+		    if (info.dli_fname) lines[i].path = info.dli_fname;
+		    if (info.dli_sname) lines[i].sname = info.dli_sname;
 		    goto next_line;
 		}
 	    }
@@ -2337,9 +2602,11 @@ rb_dump_backtrace_with_lines(int num_traces, void **traces)
 	    obj->base_addr = (uintptr_t)info.dli_fbase;
 	    path = info.dli_fname;
 	    obj->path = path;
-	    lines[i].path = path;
-            lines[i].sname = info.dli_sname;
-            lines[i].saddr = (uintptr_t)info.dli_saddr;
+	    if (path) lines[i].path = path;
+            if (info.dli_sname) {
+                lines[i].sname = info.dli_sname;
+                lines[i].saddr = (uintptr_t)info.dli_saddr;
+            }
 	    strlcpy(binary_filename, path, PATH_MAX);
 	    if (fill_lines(num_traces, traces, 1, &obj, lines, i) == (uintptr_t)-1)
 		break;
diff --git a/array.c b/array.c
index bc904ec420..b76e9a64a3 100644
--- a/array.c
+++ b/array.c
@@ -39,6 +39,37 @@
 
 VALUE rb_cArray;
 
+/* Flags of RArray
+ *
+ * 1:   RARRAY_EMBED_FLAG
+ *          The array is embedded (its contents follow the header, rather than
+ *          being on a separately allocated buffer).
+ * 2:   RARRAY_SHARED_FLAG (equal to ELTS_SHARED)
+ *          The array is shared. The buffer this array points to is owned by
+ *          another array (the shared root).
+ * if USE_RVARGC
+ * 3-9: RARRAY_EMBED_LEN
+ *          The length of the array when RARRAY_EMBED_FLAG is set.
+ * else
+ * 3-4: RARRAY_EMBED_LEN
+ *          The length of the array when RARRAY_EMBED_FLAG is set.
+ * endif
+ * 12:  RARRAY_SHARED_ROOT_FLAG
+ *          The array is a shared root that does reference counting. The buffer
+ *          this array points to is owned by this array but may be pointed to
+ *          by other arrays.
+ *          Note: Frozen arrays may be a shared root without this flag being
+ *                set. Frozen arrays do not have reference counting because
+ *                they cannot be modified. Not updating the reference count
+ *                improves copy-on-write performance. Their reference count is
+ *                assumed to be infinity.
+ * 13:  RARRAY_TRANSIENT_FLAG
+ *          The buffer of the array is allocated on the transient heap.
+ * 14:  RARRAY_PTR_IN_USE_FLAG
+ *          The buffer of the array is in use. This is only used during
+ *          debugging.
+ */
+
 /* for OPTIMIZED_CMP: */
 #define id_cmp idCmp
 
@@ -53,23 +84,6 @@ should_be_T_ARRAY(VALUE ary)
     return RB_TYPE_P(ary, T_ARRAY);
 }
 
-RBIMPL_ATTR_MAYBE_UNUSED()
-static int
-should_not_be_shared_and_embedded(VALUE ary)
-{
-    return !FL_TEST((ary), ELTS_SHARED) || !FL_TEST((ary), RARRAY_EMBED_FLAG);
-}
-
-#define ARY_SHARED_P(ary) \
-  (assert(should_be_T_ARRAY((VALUE)(ary))), \
-   assert(should_not_be_shared_and_embedded((VALUE)ary)), \
-   FL_TEST_RAW((ary),ELTS_SHARED)!=0)
-
-#define ARY_EMBED_P(ary) \
-  (assert(should_be_T_ARRAY((VALUE)(ary))), \
-   assert(should_not_be_shared_and_embedded((VALUE)ary)), \
-   FL_TEST_RAW((ary), RARRAY_EMBED_FLAG) != 0)
-
 #define ARY_HEAP_PTR(a) (assert(!ARY_EMBED_P(a)), RARRAY(a)->as.heap.ptr)
 #define ARY_HEAP_LEN(a) (assert(!ARY_EMBED_P(a)), RARRAY(a)->as.heap.len)
 #define ARY_HEAP_CAPA(a) (assert(!ARY_EMBED_P(a)), assert(!ARY_SHARED_ROOT_P(a)), \
@@ -79,11 +93,11 @@ should_not_be_shared_and_embedded(VALUE ary)
 #define ARY_EMBED_LEN(a) \
     (assert(ARY_EMBED_P(a)), \
      (long)((RBASIC(a)->flags >> RARRAY_EMBED_LEN_SHIFT) & \
-	 (RARRAY_EMBED_LEN_MASK >> RARRAY_EMBED_LEN_SHIFT)))
+         (RARRAY_EMBED_LEN_MASK >> RARRAY_EMBED_LEN_SHIFT)))
 #define ARY_HEAP_SIZE(a) (assert(!ARY_EMBED_P(a)), assert(ARY_OWNS_HEAP_P(a)), ARY_CAPA(a) * sizeof(VALUE))
 
 #define ARY_OWNS_HEAP_P(a) (assert(should_be_T_ARRAY((VALUE)(a))), \
-                            !FL_TEST_RAW((a), ELTS_SHARED|RARRAY_EMBED_FLAG))
+                            !FL_TEST_RAW((a), RARRAY_SHARED_FLAG|RARRAY_EMBED_FLAG))
 
 #define FL_SET_EMBED(a) do { \
     assert(!ARY_SHARED_P(a)); \
@@ -95,9 +109,9 @@ should_not_be_shared_and_embedded(VALUE ary)
 #define FL_UNSET_EMBED(ary) FL_UNSET((ary), RARRAY_EMBED_FLAG|RARRAY_EMBED_LEN_MASK)
 #define FL_SET_SHARED(ary) do { \
     assert(!ARY_EMBED_P(ary)); \
-    FL_SET((ary), ELTS_SHARED); \
+    FL_SET((ary), RARRAY_SHARED_FLAG); \
 } while (0)
-#define FL_UNSET_SHARED(ary) FL_UNSET((ary), ELTS_SHARED)
+#define FL_UNSET_SHARED(ary) FL_UNSET((ary), RARRAY_SHARED_FLAG)
 
 #define ARY_SET_PTR(ary, p) do { \
     assert(!ARY_EMBED_P(ary)); \
@@ -107,7 +121,6 @@ should_not_be_shared_and_embedded(VALUE ary)
 #define ARY_SET_EMBED_LEN(ary, n) do { \
     long tmp_n = (n); \
     assert(ARY_EMBED_P(ary)); \
-    assert(!OBJ_FROZEN(ary)); \
     RBASIC(ary)->flags &= ~RARRAY_EMBED_LEN_MASK; \
     RBASIC(ary)->flags |= (tmp_n) << RARRAY_EMBED_LEN_SHIFT; \
 } while (0)
@@ -148,27 +161,25 @@ should_not_be_shared_and_embedded(VALUE ary)
     RARRAY(ary)->as.heap.aux.capa = (n); \
 } while (0)
 
-#define ARY_SHARED_ROOT(ary) (assert(ARY_SHARED_P(ary)), RARRAY(ary)->as.heap.aux.shared_root)
 #define ARY_SET_SHARED(ary, value) do { \
     const VALUE _ary_ = (ary); \
     const VALUE _value_ = (value); \
     assert(!ARY_EMBED_P(_ary_)); \
     assert(ARY_SHARED_P(_ary_)); \
-    assert(ARY_SHARED_ROOT_P(_value_)); \
+    assert(!OBJ_FROZEN(_ary_)); \
+    assert(ARY_SHARED_ROOT_P(_value_) || OBJ_FROZEN(_value_)); \
     RB_OBJ_WRITE(_ary_, &RARRAY(_ary_)->as.heap.aux.shared_root, _value_); \
 } while (0)
-#define RARRAY_SHARED_ROOT_FLAG FL_USER12
-#define ARY_SHARED_ROOT_P(ary) (assert(should_be_T_ARRAY((VALUE)(ary))), \
-                                FL_TEST_RAW((ary), RARRAY_SHARED_ROOT_FLAG))
-#define ARY_SHARED_ROOT_REFCNT(ary) \
-    (assert(ARY_SHARED_ROOT_P(ary)), RARRAY(ary)->as.heap.aux.capa)
-#define ARY_SHARED_ROOT_OCCUPIED(ary) (ARY_SHARED_ROOT_REFCNT(ary) == 1)
+
+#define ARY_SHARED_ROOT_OCCUPIED(ary) (!OBJ_FROZEN(ary) && ARY_SHARED_ROOT_REFCNT(ary) == 1)
 #define ARY_SET_SHARED_ROOT_REFCNT(ary, value) do { \
     assert(ARY_SHARED_ROOT_P(ary)); \
+    assert(!OBJ_FROZEN(ary)); \
     assert((value) >= 0); \
     RARRAY(ary)->as.heap.aux.capa = (value); \
 } while (0)
 #define FL_SET_SHARED_ROOT(ary) do { \
+    assert(!OBJ_FROZEN(ary)); \
     assert(!ARY_EMBED_P(ary)); \
     assert(!RARRAY_TRANSIENT_P(ary)); \
     FL_SET((ary), RARRAY_SHARED_ROOT_FLAG); \
@@ -212,6 +223,37 @@ ary_embeddable_p(long capa)
 #endif
 }
 
+bool
+rb_ary_embeddable_p(VALUE ary)
+{
+    /* An array cannot be turned embeddable when the array is:
+     *  - Shared root: other objects may point to the buffer of this array
+     *    so we cannot make it embedded.
+     *  - Frozen: this array may also be a shared root without the shared root
+     *    flag.
+     *  - Shared: we don't want to re-embed an array that points to a shared
+     *    root (to save memory).
+     */
+    return !(ARY_SHARED_ROOT_P(ary) || OBJ_FROZEN(ary) || ARY_SHARED_P(ary));
+}
+
+size_t
+rb_ary_size_as_embedded(VALUE ary)
+{
+    size_t real_size;
+
+    if (ARY_EMBED_P(ary)) {
+        real_size = ary_embed_size(ARY_EMBED_LEN(ary));
+    }
+    else if (rb_ary_embeddable_p(ary)) {
+        real_size = ary_embed_size(ARY_HEAP_CAPA(ary));
+    }
+    else {
+        real_size = sizeof(struct RArray);
+    }
+    return real_size;
+}
+
 
 #if ARRAY_DEBUG
 #define ary_verify(ary) ary_verify_(ary, __FILE__, __LINE__)
@@ -221,12 +263,12 @@ ary_verify_(VALUE ary, const char *file, int line)
 {
     assert(RB_TYPE_P(ary, T_ARRAY));
 
-    if (FL_TEST(ary, ELTS_SHARED)) {
-        VALUE root = RARRAY(ary)->as.heap.aux.shared_root;
+    if (ARY_SHARED_P(ary)) {
+        VALUE root = ARY_SHARED_ROOT(ary);
         const VALUE *ptr = ARY_HEAP_PTR(ary);
         const VALUE *root_ptr = RARRAY_CONST_PTR_TRANSIENT(root);
         long len = ARY_HEAP_LEN(ary), root_len = RARRAY_LEN(root);
-        assert(FL_TEST(root, RARRAY_SHARED_ROOT_FLAG));
+        assert(ARY_SHARED_ROOT_P(root) || OBJ_FROZEN(root));
         assert(root_ptr <= ptr && ptr + len <= root_ptr + root_len);
         ary_verify(root);
     }
@@ -289,7 +331,7 @@ void
 rb_mem_clear(VALUE *mem, long size)
 {
     while (size--) {
-	*mem++ = Qnil;
+        *mem++ = Qnil;
     }
 }
 
@@ -297,7 +339,7 @@ static void
 ary_mem_clear(VALUE ary, long beg, long size)
 {
     RARRAY_PTR_USE_TRANSIENT(ary, ptr, {
-	rb_mem_clear(ptr + beg, size);
+        rb_mem_clear(ptr + beg, size);
     });
 }
 
@@ -305,7 +347,7 @@ static inline void
 memfill(register VALUE *mem, register long size, register VALUE val)
 {
     while (size--) {
-	*mem++ = val;
+        *mem++ = val;
     }
 }
 
@@ -313,8 +355,8 @@ static void
 ary_memfill(VALUE ary, long beg, long size, VALUE val)
 {
     RARRAY_PTR_USE_TRANSIENT(ary, ptr, {
-	memfill(ptr + beg, size, val);
-	RB_OBJ_WRITTEN(ary, Qundef, val);
+        memfill(ptr + beg, size, val);
+        RB_OBJ_WRITTEN(ary, Qundef, val);
     });
 }
 
@@ -419,14 +461,11 @@ static inline void
 rb_ary_transient_heap_evacuate_(VALUE ary, int transient, int promote)
 {
     if (transient) {
+        assert(!ARY_SHARED_ROOT_P(ary));
+
         VALUE *new_ptr;
         const VALUE *old_ptr = ARY_HEAP_PTR(ary);
         long capa = ARY_HEAP_CAPA(ary);
-        long len  = ARY_HEAP_LEN(ary);
-
-        if (ARY_SHARED_ROOT_P(ary)) {
-            capa = len;
-        }
 
         assert(ARY_OWNS_HEAP_P(ary));
         assert(RARRAY_TRANSIENT_P(ary));
@@ -468,6 +507,27 @@ rb_ary_detransient(VALUE ary)
 }
 #endif
 
+void
+rb_ary_make_embedded(VALUE ary)
+{
+    assert(rb_ary_embeddable_p(ary));
+    if (!ARY_EMBED_P(ary)) {
+        const VALUE *buf = ARY_HEAP_PTR(ary);
+        long len = ARY_HEAP_LEN(ary);
+        bool was_transient = RARRAY_TRANSIENT_P(ary);
+
+        // FL_SET_EMBED also unsets the transient flag
+        FL_SET_EMBED(ary);
+        ARY_SET_EMBED_LEN(ary, len);
+
+        MEMCPY((void *)ARY_EMBED_PTR(ary), (void *)buf, VALUE, len);
+
+        if (!was_transient) {
+            ary_heap_free_ptr(ary, buf, len * sizeof(VALUE));
+        }
+    }
+}
+
 static void
 ary_resize_capa(VALUE ary, long capacity)
 {
@@ -527,10 +587,10 @@ ary_double_capa(VALUE ary, long min)
     long new_capa = ARY_CAPA(ary) / 2;
 
     if (new_capa < ARY_DEFAULT_SIZE) {
-	new_capa = ARY_DEFAULT_SIZE;
+        new_capa = ARY_DEFAULT_SIZE;
     }
     if (new_capa >= ARY_MAX_SIZE - min) {
-	new_capa = (ARY_MAX_SIZE - min) / 2;
+        new_capa = (ARY_MAX_SIZE - min) / 2;
     }
     new_capa += min;
     ary_resize_capa(ary, new_capa);
@@ -541,14 +601,16 @@ ary_double_capa(VALUE ary, long min)
 static void
 rb_ary_decrement_share(VALUE shared_root)
 {
-    long num = ARY_SHARED_ROOT_REFCNT(shared_root);
-    ARY_SET_SHARED_ROOT_REFCNT(shared_root, num - 1);
+    if (!OBJ_FROZEN(shared_root)) {
+        long num = ARY_SHARED_ROOT_REFCNT(shared_root);
+        ARY_SET_SHARED_ROOT_REFCNT(shared_root, num - 1);
+    }
 }
 
 static void
 rb_ary_unshare(VALUE ary)
 {
-    VALUE shared_root = RARRAY(ary)->as.heap.aux.shared_root;
+    VALUE shared_root = ARY_SHARED_ROOT(ary);
     rb_ary_decrement_share(shared_root);
     FL_UNSET_SHARED(ary);
 }
@@ -570,9 +632,11 @@ rb_ary_reset(VALUE ary)
 static VALUE
 rb_ary_increment_share(VALUE shared_root)
 {
-    long num = ARY_SHARED_ROOT_REFCNT(shared_root);
-    assert(num >= 0);
-    ARY_SET_SHARED_ROOT_REFCNT(shared_root, num + 1);
+    if (!OBJ_FROZEN(shared_root)) {
+        long num = ARY_SHARED_ROOT_REFCNT(shared_root);
+        assert(num >= 0);
+        ARY_SET_SHARED_ROOT_REFCNT(shared_root, num + 1);
+    }
     return shared_root;
 }
 
@@ -648,40 +712,40 @@ ary_ensure_room_for_push(VALUE ary, long add_len)
     long capa;
 
     if (old_len > ARY_MAX_SIZE - add_len) {
-	rb_raise(rb_eIndexError, "index %ld too big", new_len);
+        rb_raise(rb_eIndexError, "index %ld too big", new_len);
     }
     if (ARY_SHARED_P(ary)) {
-	if (new_len > ary_embed_capa(ary)) {
+        if (new_len > ary_embed_capa(ary)) {
             VALUE shared_root = ARY_SHARED_ROOT(ary);
             if (ARY_SHARED_ROOT_OCCUPIED(shared_root)) {
                 if (ARY_HEAP_PTR(ary) - RARRAY_CONST_PTR_TRANSIENT(shared_root) + new_len <= RARRAY_LEN(shared_root)) {
-		    rb_ary_modify_check(ary);
+                    rb_ary_modify_check(ary);
 
                     ary_verify(ary);
                     ary_verify(shared_root);
                     return shared_root;
-		}
-		else {
-		    /* if array is shared, then it is likely it participate in push/shift pattern */
-		    rb_ary_modify(ary);
-		    capa = ARY_CAPA(ary);
-		    if (new_len > capa - (capa >> 6)) {
-			ary_double_capa(ary, new_len);
-		    }
+                }
+                else {
+                    /* if array is shared, then it is likely it participate in push/shift pattern */
+                    rb_ary_modify(ary);
+                    capa = ARY_CAPA(ary);
+                    if (new_len > capa - (capa >> 6)) {
+                        ary_double_capa(ary, new_len);
+                    }
                     ary_verify(ary);
-		    return ary;
-		}
-	    }
-	}
+                    return ary;
+                }
+            }
+        }
         ary_verify(ary);
         rb_ary_modify(ary);
     }
     else {
-	rb_ary_modify_check(ary);
+        rb_ary_modify_check(ary);
     }
     capa = ARY_CAPA(ary);
     if (new_len > capa) {
-	ary_double_capa(ary, new_len);
+        ary_double_capa(ary, new_len);
     }
 
     ary_verify(ary);
@@ -693,6 +757,7 @@ ary_ensure_room_for_push(VALUE ary, long add_len)
  *    array.freeze -> self
  *
  *  Freezes +self+; returns +self+:
+ *
  *    a = []
  *    a.frozen? # => false
  *    a.freeze
@@ -718,10 +783,10 @@ VALUE
 rb_ary_shared_with_p(VALUE ary1, VALUE ary2)
 {
     if (!ARY_EMBED_P(ary1) && ARY_SHARED_P(ary1) &&
-	!ARY_EMBED_P(ary2) && ARY_SHARED_P(ary2) &&
-        RARRAY(ary1)->as.heap.aux.shared_root == RARRAY(ary2)->as.heap.aux.shared_root &&
-	RARRAY(ary1)->as.heap.len == RARRAY(ary2)->as.heap.len) {
-	return Qtrue;
+            !ARY_EMBED_P(ary2) && ARY_SHARED_P(ary2) &&
+            ARY_SHARED_ROOT(ary1) == ARY_SHARED_ROOT(ary2) &&
+            ARY_HEAP_LEN(ary1) == ARY_HEAP_LEN(ary2)) {
+        return Qtrue;
     }
     return Qfalse;
 }
@@ -766,10 +831,10 @@ ary_new(VALUE klass, long capa)
     VALUE ary,*ptr;
 
     if (capa < 0) {
-	rb_raise(rb_eArgError, "negative array size (or size too big)");
+        rb_raise(rb_eArgError, "negative array size (or size too big)");
     }
     if (capa > ARY_MAX_SIZE) {
-	rb_raise(rb_eArgError, "array size too big");
+        rb_raise(rb_eArgError, "array size too big");
     }
 
     RUBY_DTRACE_CREATE_HOOK(ARRAY, capa);
@@ -779,11 +844,11 @@ ary_new(VALUE klass, long capa)
     }
     else {
         ary = ary_alloc_heap(klass);
+        ARY_SET_CAPA(ary, capa);
         assert(!ARY_EMBED_P(ary));
 
         ptr = ary_heap_alloc(ary, capa);
         ARY_SET_PTR(ary, ptr);
-        ARY_SET_CAPA(ary, capa);
         ARY_SET_HEAP_LEN(ary, 0);
     }
 
@@ -813,7 +878,7 @@ VALUE
 
     va_start(ar, n);
     for (i=0; i<n; i++) {
-	ARY_SET(ary, i, va_arg(ar, VALUE));
+        ARY_SET(ary, i, va_arg(ar, VALUE));
     }
     va_end(ar);
 
@@ -828,8 +893,8 @@ rb_ary_tmp_new_from_values(VALUE klass, long n, const VALUE *elts)
 
     ary = ary_new(klass, n);
     if (n > 0 && elts) {
-	ary_memcpy(ary, 0, n, elts);
-	ARY_SET_LEN(ary, n);
+        ary_memcpy(ary, 0, n, elts);
+        ARY_SET_LEN(ary, n);
     }
 
     return ary;
@@ -874,10 +939,10 @@ ec_ary_new(rb_execution_context_t *ec, VALUE klass, long capa)
     VALUE ary,*ptr;
 
     if (capa < 0) {
-	rb_raise(rb_eArgError, "negative array size (or size too big)");
+        rb_raise(rb_eArgError, "negative array size (or size too big)");
     }
     if (capa > ARY_MAX_SIZE) {
-	rb_raise(rb_eArgError, "array size too big");
+        rb_raise(rb_eArgError, "array size too big");
     }
 
     RUBY_DTRACE_CREATE_HOOK(ARRAY, capa);
@@ -887,11 +952,11 @@ ec_ary_new(rb_execution_context_t *ec, VALUE klass, long capa)
     }
     else {
         ary = ec_ary_alloc_heap(ec, klass);
+        ARY_SET_CAPA(ary, capa);
         assert(!ARY_EMBED_P(ary));
 
         ptr = ary_heap_alloc(ary, capa);
         ARY_SET_PTR(ary, ptr);
-        ARY_SET_CAPA(ary, capa);
         ARY_SET_HEAP_LEN(ary, 0);
     }
 
@@ -905,15 +970,15 @@ rb_ec_ary_new_from_values(rb_execution_context_t *ec, long n, const VALUE *elts)
 
     ary = ec_ary_new(ec, rb_cArray, n);
     if (n > 0 && elts) {
-	ary_memcpy(ary, 0, n, elts);
-	ARY_SET_LEN(ary, n);
+        ary_memcpy(ary, 0, n, elts);
+        ARY_SET_LEN(ary, n);
     }
 
     return ary;
 }
 
 VALUE
-rb_ary_tmp_new(long capa)
+rb_ary_hidden_new(long capa)
 {
     VALUE ary = ary_new(0, capa);
     rb_ary_transient_heap_evacuate(ary, TRUE);
@@ -921,12 +986,11 @@ rb_ary_tmp_new(long capa)
 }
 
 VALUE
-rb_ary_tmp_new_fill(long capa)
+rb_ary_hidden_new_fill(long capa)
 {
-    VALUE ary = ary_new(0, capa);
+    VALUE ary = rb_ary_hidden_new(capa);
     ary_memfill(ary, 0, capa, Qnil);
     ARY_SET_LEN(ary, capa);
-    rb_ary_transient_heap_evacuate(ary, TRUE);
     return ary;
 }
 
@@ -964,64 +1028,69 @@ RUBY_FUNC_EXPORTED size_t
 rb_ary_memsize(VALUE ary)
 {
     if (ARY_OWNS_HEAP_P(ary)) {
-	return ARY_CAPA(ary) * sizeof(VALUE);
+        return ARY_CAPA(ary) * sizeof(VALUE);
     }
     else {
-	return 0;
+        return 0;
     }
 }
 
-static inline void
-ary_discard(VALUE ary)
-{
-    rb_ary_free(ary);
-    RBASIC(ary)->flags |= RARRAY_EMBED_FLAG;
-    RBASIC(ary)->flags &= ~(RARRAY_EMBED_LEN_MASK | RARRAY_TRANSIENT_FLAG);
-}
-
 static VALUE
 ary_make_shared(VALUE ary)
 {
-    assert(!ARY_EMBED_P(ary));
+    assert(USE_RVARGC || !ARY_EMBED_P(ary));
     ary_verify(ary);
 
     if (ARY_SHARED_P(ary)) {
         return ARY_SHARED_ROOT(ary);
     }
     else if (ARY_SHARED_ROOT_P(ary)) {
-	return ary;
+        return ary;
     }
     else if (OBJ_FROZEN(ary)) {
-        rb_ary_transient_heap_evacuate(ary, TRUE);
-	ary_shrink_capa(ary);
-	FL_SET_SHARED_ROOT(ary);
-        ARY_SET_SHARED_ROOT_REFCNT(ary, 1);
-	return ary;
+        if (!ARY_EMBED_P(ary)) {
+            rb_ary_transient_heap_evacuate(ary, TRUE);
+            ary_shrink_capa(ary);
+        }
+        return ary;
     }
     else {
-	long capa = ARY_CAPA(ary), len = RARRAY_LEN(ary);
-        const VALUE *ptr;
+        rb_ary_transient_heap_evacuate(ary, TRUE);
+
+        long capa = ARY_CAPA(ary);
+        long len = RARRAY_LEN(ary);
+
+        /* Shared roots cannot be embedded because the reference count
+         * (refcnt) is stored in as.heap.aux.capa. */
         VALUE shared = ary_alloc_heap(0);
-        VALUE vshared = (VALUE)shared;
+        FL_SET_SHARED_ROOT(shared);
 
-        rb_ary_transient_heap_evacuate(ary, TRUE);
-        ptr = ARY_HEAP_PTR(ary);
-
-        FL_UNSET_EMBED(vshared);
-        ARY_SET_LEN(vshared, capa);
-        ARY_SET_PTR(vshared, ptr);
-        ary_mem_clear(vshared, len, capa - len);
-        FL_SET_SHARED_ROOT(vshared);
-        ARY_SET_SHARED_ROOT_REFCNT(vshared, 1);
-	FL_SET_SHARED(ary);
+        if (ARY_EMBED_P(ary)) {
+            /* Cannot use ary_heap_alloc because we don't want to allocate
+             * on the transient heap. */
+            VALUE *ptr = ALLOC_N(VALUE, capa);
+            ARY_SET_PTR(shared, ptr);
+            ary_memcpy(shared, 0, len, RARRAY_PTR(ary));
+
+            FL_UNSET_EMBED(ary);
+            ARY_SET_HEAP_LEN(ary, len);
+            ARY_SET_PTR(ary, ptr);
+        }
+        else {
+            ARY_SET_PTR(shared, RARRAY_PTR(ary));
+        }
+
+        ARY_SET_LEN(shared, capa);
+        ary_mem_clear(shared, len, capa - len);
+        ARY_SET_SHARED_ROOT_REFCNT(shared, 1);
+        FL_SET_SHARED(ary);
         RB_DEBUG_COUNTER_INC(obj_ary_shared_create);
-        ARY_SET_SHARED(ary, vshared);
-        OBJ_FREEZE(vshared);
+        ARY_SET_SHARED(ary, shared);
 
-        ary_verify(vshared);
+        ary_verify(shared);
         ary_verify(ary);
 
-        return vshared;
+        return shared;
     }
 }
 
@@ -1132,6 +1201,7 @@ rb_ary_s_new(int argc, VALUE *argv, VALUE klass)
  *
  *  With no block and a single \Array argument +array+,
  *  returns a new \Array formed from +array+:
+ *
  *    a = Array.new([:foo, 'bar', 2])
  *    a.class # => Array
  *    a # => [:foo, "bar", 2]
@@ -1139,12 +1209,14 @@ rb_ary_s_new(int argc, VALUE *argv, VALUE klass)
  *  With no block and a single \Integer argument +size+,
  *  returns a new \Array of the given size
  *  whose elements are all +nil+:
+ *
  *    a = Array.new(3)
  *    a # => [nil, nil, nil]
  *
  *  With no block and arguments +size+ and +default_value+,
  *  returns an \Array of the given size;
  *  each element is that same +default_value+:
+ *
  *    a = Array.new(3, 'x')
  *    a # => ['x', 'x', 'x']
  *
@@ -1152,6 +1224,7 @@ rb_ary_s_new(int argc, VALUE *argv, VALUE klass)
  *  returns an \Array of the given size;
  *  the block is called with each successive integer +index+;
  *  the element for that +index+ is the return value from the block:
+ *
  *    a = Array.new(3) {|index| "Element #{index}" }
  *    a # => ["Element 0", "Element 1", "Element 2"]
  *
@@ -1173,45 +1246,45 @@ rb_ary_initialize(int argc, VALUE *argv, VALUE ary)
         rb_ary_reset(ary);
         assert(ARY_EMBED_P(ary));
         assert(ARY_EMBED_LEN(ary) == 0);
-	if (rb_block_given_p()) {
-	    rb_warning("given block not used");
-	}
-	return ary;
+        if (rb_block_given_p()) {
+            rb_warning("given block not used");
+        }
+        return ary;
     }
     rb_scan_args(argc, argv, "02", &size, &val);
     if (argc == 1 && !FIXNUM_P(size)) {
-	val = rb_check_array_type(size);
-	if (!NIL_P(val)) {
-	    rb_ary_replace(ary, val);
-	    return ary;
-	}
+        val = rb_check_array_type(size);
+        if (!NIL_P(val)) {
+            rb_ary_replace(ary, val);
+            return ary;
+        }
     }
 
     len = NUM2LONG(size);
     /* NUM2LONG() may call size.to_int, ary can be frozen, modified, etc */
     if (len < 0) {
-	rb_raise(rb_eArgError, "negative array size");
+        rb_raise(rb_eArgError, "negative array size");
     }
     if (len > ARY_MAX_SIZE) {
-	rb_raise(rb_eArgError, "array size too big");
+        rb_raise(rb_eArgError, "array size too big");
     }
     /* recheck after argument conversion */
     rb_ary_modify(ary);
     ary_resize_capa(ary, len);
     if (rb_block_given_p()) {
-	long i;
+        long i;
 
-	if (argc == 2) {
-	    rb_warn("block supersedes default value argument");
-	}
-	for (i=0; i<len; i++) {
-	    rb_ary_store(ary, i, rb_yield(LONG2NUM(i)));
-	    ARY_SET_LEN(ary, i + 1);
-	}
+        if (argc == 2) {
+            rb_warn("block supersedes default value argument");
+        }
+        for (i=0; i<len; i++) {
+            rb_ary_store(ary, i, rb_yield(LONG2NUM(i)));
+            ARY_SET_LEN(ary, i + 1);
+        }
     }
     else {
-	ary_memfill(ary, 0, len, val);
-	ARY_SET_LEN(ary, len);
+        ary_memfill(ary, 0, len, val);
+        ARY_SET_LEN(ary, len);
     }
     return ary;
 }
@@ -1242,26 +1315,26 @@ rb_ary_store(VALUE ary, long idx, VALUE val)
     long len = RARRAY_LEN(ary);
 
     if (idx < 0) {
-	idx += len;
-	if (idx < 0) {
-	    rb_raise(rb_eIndexError, "index %ld too small for array; minimum: %ld",
-		     idx - len, -len);
-	}
+        idx += len;
+        if (idx < 0) {
+            rb_raise(rb_eIndexError, "index %ld too small for array; minimum: %ld",
+                     idx - len, -len);
+        }
     }
     else if (idx >= ARY_MAX_SIZE) {
-	rb_raise(rb_eIndexError, "index %ld too big", idx);
+        rb_raise(rb_eIndexError, "index %ld too big", idx);
     }
 
     rb_ary_modify(ary);
     if (idx >= ARY_CAPA(ary)) {
-	ary_double_capa(ary, idx);
+        ary_double_capa(ary, idx);
     }
     if (idx > len) {
-	ary_mem_clear(ary, len, idx - len + 1);
+        ary_mem_clear(ary, len, idx - len + 1);
     }
 
     if (idx >= len) {
-	ARY_SET_LEN(ary, idx + 1);
+        ARY_SET_LEN(ary, idx + 1);
     }
     ARY_SET(ary, idx, val);
 }
@@ -1273,17 +1346,20 @@ ary_make_partial(VALUE ary, VALUE klass, long offset, long len)
     assert(len >= 0);
     assert(offset+len <= RARRAY_LEN(ary));
 
-    if (ary_embeddable_p(len)) {
+    const size_t rarray_embed_capa_max = (sizeof(struct RArray) - offsetof(struct RArray, as.ary)) / sizeof(VALUE);
+
+    if ((size_t)len <= rarray_embed_capa_max && ary_embeddable_p(len)) {
         VALUE result = ary_alloc_embed(klass, len);
         ary_memcpy(result, 0, len, RARRAY_CONST_PTR_TRANSIENT(ary) + offset);
         ARY_SET_EMBED_LEN(result, len);
         return result;
     }
     else {
-        VALUE shared, result = ary_alloc_heap(klass);
+        VALUE shared = ary_make_shared(ary);
+
+        VALUE result = ary_alloc_heap(klass);
         assert(!ARY_EMBED_P(result));
 
-        shared = ary_make_shared(ary);
         ARY_SET_PTR(result, RARRAY_CONST_PTR_TRANSIENT(ary));
         ARY_SET_LEN(result, RARRAY_LEN(ary));
         rb_ary_set_shared(result, shared);
@@ -1308,16 +1384,19 @@ ary_make_partial_step(VALUE ary, VALUE klass, long offset, long len, long step)
     const VALUE *values = RARRAY_CONST_PTR_TRANSIENT(ary);
     const long orig_len = len;
 
-    if ((step > 0 && step >= len) || (step < 0 && (step < -len))) {
+    if (step > 0 && step >= len) {
         VALUE result = ary_new(klass, 1);
         VALUE *ptr = (VALUE *)ARY_EMBED_PTR(result);
         RB_OBJ_WRITE(result, ptr, values[offset]);
         ARY_SET_EMBED_LEN(result, 1);
         return result;
     }
+    else if (step < 0 && step < -len) {
+        step = -len;
+    }
 
     long ustep = (step < 0) ? -step : step;
-    len = (len + ustep - 1) / ustep;
+    len = roomof(len, ustep);
 
     long i;
     long j = offset + ((step > 0) ? 0 : (orig_len - 1));
@@ -1372,13 +1451,13 @@ ary_take_first_or_last(int argc, const VALUE *argv, VALUE ary, enum ary_take_pos
     n = NUM2LONG(argv[0]);
     len = RARRAY_LEN(ary);
     if (n > len) {
-	n = len;
+        n = len;
     }
     else if (n < 0) {
-	rb_raise(rb_eArgError, "negative array size");
+        rb_raise(rb_eArgError, "negative array size");
     }
     if (last) {
-	offset = len - n;
+        offset = len - n;
     }
     return ary_make_partial(ary, rb_cArray, offset, n);
 }
@@ -1388,13 +1467,16 @@ ary_take_first_or_last(int argc, const VALUE *argv, VALUE ary, enum ary_take_pos
  *    array << object -> self
  *
  *  Appends +object+ to +self+; returns +self+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a << :baz # => [:foo, "bar", 2, :baz]
  *
  *  Appends +object+ as one element, even if it is another \Array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a1 = a << [3, 4]
  *    a1 # => [:foo, "bar", 2, [3, 4]]
+ *
  */
 
 VALUE
@@ -1403,7 +1485,7 @@ rb_ary_push(VALUE ary, VALUE item)
     long idx = RARRAY_LEN((ary_verify(ary), ary));
     VALUE target_ary = ary_ensure_room_for_push(ary, 1);
     RARRAY_PTR_USE_TRANSIENT(ary, ptr, {
-	RB_OBJ_WRITE(target_ary, &ptr[idx], item);
+        RB_OBJ_WRITE(target_ary, &ptr[idx], item);
     });
     ARY_SET_LEN(ary, idx + 1);
     ary_verify(ary);
@@ -1427,10 +1509,12 @@ rb_ary_cat(VALUE ary, const VALUE *argv, long len)
  *  Appends trailing elements.
  *
  *  Appends each argument in +objects+ to +self+;  returns +self+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.push(:baz, :bat) # => [:foo, "bar", 2, :baz, :bat]
  *
  *  Appends each argument as one element, even if it is another \Array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a1 = a.push([:baz, :bat], [:bam, :bad])
  *    a1 # => [:foo, "bar", 2, [:baz, :bat], [:bam, :bad]]
@@ -1454,10 +1538,10 @@ rb_ary_pop(VALUE ary)
     n = RARRAY_LEN(ary);
     if (n == 0) return Qnil;
     if (ARY_OWNS_HEAP_P(ary) &&
-	n * 3 < ARY_CAPA(ary) &&
-	ARY_CAPA(ary) > ARY_DEFAULT_SIZE)
+        n * 3 < ARY_CAPA(ary) &&
+        ARY_CAPA(ary) > ARY_DEFAULT_SIZE)
     {
-	ary_resize_capa(ary, n * 2);
+        ary_resize_capa(ary, n * 2);
     }
     --n;
     ARY_SET_LEN(ary, n);
@@ -1474,6 +1558,7 @@ rb_ary_pop(VALUE ary)
  *
  *  When no argument is given and +self+ is not empty,
  *  removes and returns the last element:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.pop # => 2
  *    a # => [:foo, "bar"]
@@ -1481,12 +1566,14 @@ rb_ary_pop(VALUE ary)
  *  Returns +nil+ if the array is empty.
  *
  *  When a non-negative \Integer argument +n+ is given and is in range,
+ *
  *  removes and returns the last +n+ elements in a new \Array:
  *    a = [:foo, 'bar', 2]
  *    a.pop(2) # => ["bar", 2]
  *
  *  If +n+ is positive and out of range,
  *  removes and returns all elements:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.pop(50) # => [:foo, "bar", 2]
  *
@@ -1499,7 +1586,7 @@ rb_ary_pop_m(int argc, VALUE *argv, VALUE ary)
     VALUE result;
 
     if (argc == 0) {
-	return rb_ary_pop(ary);
+        return rb_ary_pop(ary);
     }
 
     rb_ary_modify_check(ary);
@@ -1535,6 +1622,7 @@ rb_ary_shift(VALUE ary)
  *  Removes and returns leading elements.
  *
  *  When no argument is given, removes and returns the first element:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.shift # => :foo
  *    a # => ['bar', 2]
@@ -1543,12 +1631,14 @@ rb_ary_shift(VALUE ary)
  *
  *  When positive \Integer argument +n+ is given, removes the first +n+ elements;
  *  returns those elements in a new \Array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.shift(2) # => [:foo, 'bar']
  *    a # => [2]
  *
  *  If +n+ is as large as or larger than <tt>self.length</tt>,
  *  removes all elements; returns those elements in a new \Array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.shift(3) # => [:foo, 'bar', 2]
  *
@@ -1564,7 +1654,7 @@ rb_ary_shift_m(int argc, VALUE *argv, VALUE ary)
     long n;
 
     if (argc == 0) {
-	return rb_ary_shift(ary);
+        return rb_ary_shift(ary);
     }
 
     rb_ary_modify_check(ary);
@@ -1636,7 +1726,7 @@ ary_modify_for_unshift(VALUE ary, int argc)
     rb_ary_modify(ary);
     capa = ARY_CAPA(ary);
     if (capa - (capa >> 6) <= new_len) {
-	ary_double_capa(ary, new_len);
+        ary_double_capa(ary, new_len);
     }
 
     /* use shared array for big "queues" */
@@ -1644,20 +1734,20 @@ ary_modify_for_unshift(VALUE ary, int argc)
         ary_verify(ary);
 
         /* make a room for unshifted items */
-	capa = ARY_CAPA(ary);
-	ary_make_shared(ary);
+        capa = ARY_CAPA(ary);
+        ary_make_shared(ary);
 
         head = sharedp = RARRAY_CONST_PTR_TRANSIENT(ary);
         return make_room_for_unshift(ary, head, (void *)sharedp, argc, capa, len);
     }
     else {
-	/* sliding items */
+        /* sliding items */
         RARRAY_PTR_USE_TRANSIENT(ary, ptr, {
-	    MEMMOVE(ptr + argc, ptr, VALUE, len);
-	});
+            MEMMOVE(ptr + argc, ptr, VALUE, len);
+        });
 
         ary_verify(ary);
-	return ary;
+        return ary;
     }
 }
 
@@ -1698,6 +1788,7 @@ ary_ensure_room_for_unshift(VALUE ary, int argc)
  *    array.unshift(*objects) -> self
  *
  *  Prepends the given +objects+ to +self+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.unshift(:bam, :bat) # => [:bam, :bat, :foo, "bar", 2]
  *
@@ -1713,8 +1804,8 @@ rb_ary_unshift_m(int argc, VALUE *argv, VALUE ary)
     VALUE target_ary;
 
     if (argc == 0) {
-	rb_ary_modify_check(ary);
-	return ary;
+        rb_ary_modify_check(ary);
+        return ary;
     }
 
     target_ary = ary_ensure_room_for_unshift(ary, argc);
@@ -1736,7 +1827,7 @@ rb_ary_elt(VALUE ary, long offset)
     long len = RARRAY_LEN(ary);
     if (len == 0) return Qnil;
     if (offset < 0 || len <= offset) {
-	return Qnil;
+        return Qnil;
     }
     return RARRAY_AREF(ary, offset);
 }
@@ -1757,7 +1848,7 @@ rb_ary_subseq_step(VALUE ary, long beg, long len, long step)
     if (beg < 0 || len < 0) return Qnil;
 
     if (alen < len || alen < beg + len) {
-	len = alen - beg;
+        len = alen - beg;
     }
     klass = rb_cArray;
     if (len == 0) return ary_new(klass, 0);
@@ -1791,12 +1882,14 @@ static VALUE rb_ary_aref2(VALUE ary, VALUE b, VALUE e);
  *  Returns elements from +self+; does not modify +self+.
  *
  *  When a single \Integer argument +index+ is given, returns the element at offset +index+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[0] # => :foo
  *    a[2] # => 2
  *    a # => [:foo, "bar", 2]
  *
  *  If +index+ is negative, counts relative to the end of +self+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[-1] # => 2
  *    a[-2] # => "bar"
@@ -1805,12 +1898,14 @@ static VALUE rb_ary_aref2(VALUE ary, VALUE b, VALUE e);
  *
  *  When two \Integer arguments +start+ and +length+ are given,
  *  returns a new \Array of size +length+ containing successive elements beginning at offset +start+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[0, 2] # => [:foo, "bar"]
  *    a[1, 2] # => ["bar", 2]
  *
  *  If <tt>start + length</tt> is greater than <tt>self.length</tt>,
  *  returns all elements from offset +start+ to the end:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[0, 4] # => [:foo, "bar", 2]
  *    a[1, 3] # => ["bar", 2]
@@ -1824,6 +1919,7 @@ static VALUE rb_ary_aref2(VALUE ary, VALUE b, VALUE e);
  *  When a single \Range argument +range+ is given,
  *  treats <tt>range.min</tt> as +start+ above
  *  and <tt>range.size</tt> as +length+ above:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[0..1] # => [:foo, "bar"]
  *    a[1..2] # => ["bar", 2]
@@ -1831,18 +1927,21 @@ static VALUE rb_ary_aref2(VALUE ary, VALUE b, VALUE e);
  *  Special case: If <tt>range.start == a.size</tt>, returns a new empty \Array.
  *
  *  If <tt>range.end</tt> is negative, calculates the end index from the end:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[0..-1] # => [:foo, "bar", 2]
  *    a[0..-2] # => [:foo, "bar"]
  *    a[0..-3] # => [:foo]
  *
  *  If <tt>range.start</tt> is negative, calculates the start index from the end:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[-1..2] # => [2]
  *    a[-2..2] # => ["bar", 2]
  *    a[-3..2] # => [:foo, "bar", 2]
  *
  *  If <tt>range.start</tt> is larger than the array size, returns +nil+.
+ *
  *    a = [:foo, 'bar', 2]
  *    a[4..1] # => nil
  *    a[4..0] # => nil
@@ -1851,11 +1950,13 @@ static VALUE rb_ary_aref2(VALUE ary, VALUE b, VALUE e);
  *  When a single Enumerator::ArithmeticSequence argument +aseq+ is given,
  *  returns an \Array of elements corresponding to the indexes produced by
  *  the sequence.
+ *
  *    a = ['--', 'data1', '--', 'data2', '--', 'data3']
  *    a[(1..).step(2)] # => ["data1", "data2", "data3"]
  *
  *  Unlike slicing with range, if the start or the end of the arithmetic sequence
  *  is larger than array size, throws RangeError.
+ *
  *    a = ['--', 'data1', '--', 'data2', '--', 'data3']
  *    a[(1..11).step(2)]
  *    # RangeError (((1..11).step(2)) out of range)
@@ -1864,6 +1965,7 @@ static VALUE rb_ary_aref2(VALUE ary, VALUE b, VALUE e);
  *
  *  If given a single argument, and its type is not one of the listed, tries to
  *  convert it to Integer, and raises if it is impossible:
+ *
  *    a = [:foo, 'bar', 2]
  *    # Raises TypeError (no implicit conversion of Symbol into Integer):
  *    a[:foo]
@@ -1876,7 +1978,7 @@ rb_ary_aref(int argc, const VALUE *argv, VALUE ary)
 {
     rb_check_arity(argc, 1, 2);
     if (argc == 2) {
-	return rb_ary_aref2(ary, argv[0], argv[1]);
+        return rb_ary_aref2(ary, argv[0], argv[1]);
     }
     return rb_ary_aref1(ary, argv[0]);
 }
@@ -1887,7 +1989,7 @@ rb_ary_aref2(VALUE ary, VALUE b, VALUE e)
     long beg = NUM2LONG(b);
     long len = NUM2LONG(e);
     if (beg < 0) {
-	beg += RARRAY_LEN(ary);
+        beg += RARRAY_LEN(ary);
     }
     return rb_ary_subseq(ary, beg, len);
 }
@@ -1899,7 +2001,7 @@ rb_ary_aref1(VALUE ary, VALUE arg)
 
     /* special case - speeding up */
     if (FIXNUM_P(arg)) {
-	return rb_ary_entry(ary, FIX2LONG(arg));
+        return rb_ary_entry(ary, FIX2LONG(arg));
     }
     /* check if idx is Range or ArithmeticSequence */
     switch (rb_arithmetic_sequence_beg_len_step(arg, &beg, &len, &step, RARRAY_LEN(ary), 0)) {
@@ -1922,6 +2024,7 @@ rb_ary_aref1(VALUE ary, VALUE arg)
  *    a = [:foo, 'bar', 2]
  *    a.at(0) # => :foo
  *    a.at(2) # => 2
+ *
  */
 
 VALUE
@@ -1938,6 +2041,7 @@ rb_ary_at(VALUE ary, VALUE pos)
  *  Returns elements from +self+; does not modify +self+.
  *
  *  When no argument is given, returns the first element:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.first # => :foo
  *    a # => [:foo, "bar", 2]
@@ -1946,14 +2050,17 @@ rb_ary_at(VALUE ary, VALUE pos)
  *
  *  When non-negative \Integer argument +n+ is given,
  *  returns the first +n+ elements in a new \Array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.first(2) # => [:foo, "bar"]
  *
  *  If <tt>n >= array.size</tt>, returns all elements:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.first(50) # => [:foo, "bar", 2]
  *
  *  If <tt>n == 0</tt> returns an new empty \Array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.first(0) # []
  *
@@ -1963,11 +2070,11 @@ static VALUE
 rb_ary_first(int argc, VALUE *argv, VALUE ary)
 {
     if (argc == 0) {
-	if (RARRAY_LEN(ary) == 0) return Qnil;
-	return RARRAY_AREF(ary, 0);
+        if (RARRAY_LEN(ary) == 0) return Qnil;
+        return RARRAY_AREF(ary, 0);
     }
     else {
-	return ary_take_first_or_last(argc, argv, ary, ARY_TAKE_FIRST);
+        return ary_take_first_or_last(argc, argv, ary, ARY_TAKE_FIRST);
     }
 }
 
@@ -1979,22 +2086,26 @@ rb_ary_first(int argc, VALUE *argv, VALUE ary)
  *  Returns elements from +self+; +self+ is not modified.
  *
  *  When no argument is given, returns the last element:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.last # => 2
  *    a # => [:foo, "bar", 2]
  *
  *  If +self+ is empty, returns +nil+.
  *
- *  When non-negative \Innteger argument +n+ is given,
+ *  When non-negative \Integer argument +n+ is given,
  *  returns the last +n+ elements in a new \Array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.last(2) # => ["bar", 2]
  *
  *  If <tt>n >= array.size</tt>, returns all elements:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.last(50) # => [:foo, "bar", 2]
  *
  *  If <tt>n == 0</tt>, returns an new empty \Array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.last(0) # []
  *
@@ -2005,12 +2116,12 @@ VALUE
 rb_ary_last(int argc, const VALUE *argv, VALUE ary)
 {
     if (argc == 0) {
-	long len = RARRAY_LEN(ary);
-	if (len == 0) return Qnil;
-	return RARRAY_AREF(ary, len-1);
+        long len = RARRAY_LEN(ary);
+        if (len == 0) return Qnil;
+        return RARRAY_AREF(ary, len-1);
     }
     else {
-	return ary_take_first_or_last(argc, argv, ary, ARY_TAKE_LAST);
+        return ary_take_first_or_last(argc, argv, ary, ARY_TAKE_LAST);
     }
 }
 
@@ -2024,10 +2135,12 @@ rb_ary_last(int argc, const VALUE *argv, VALUE ary)
  *
  *  With the single \Integer argument +index+,
  *  returns the element at offset +index+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.fetch(1) # => "bar"
  *
  *  If +index+ is negative, counts from the end of the array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.fetch(-1) # => 2
  *    a.fetch(-2) # => "bar"
@@ -2035,6 +2148,7 @@ rb_ary_last(int argc, const VALUE *argv, VALUE ary)
  *  With arguments +index+ and +default_value+,
  *  returns the element at offset +index+ if index is in range,
  *  otherwise returns +default_value+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.fetch(1, nil) # => "bar"
  *
@@ -2045,6 +2159,7 @@ rb_ary_last(int argc, const VALUE *argv, VALUE ary)
  *    a = [:foo, 'bar', 2]
  *    a.fetch(1) {|index| raise 'Cannot happen' } # => "bar"
  *    a.fetch(50) {|index| "Value for #{index}" } # => "Value for 50"
+ *
  */
 
 static VALUE
@@ -2057,20 +2172,20 @@ rb_ary_fetch(int argc, VALUE *argv, VALUE ary)
     rb_scan_args(argc, argv, "11", &pos, &ifnone);
     block_given = rb_block_given_p();
     if (block_given && argc == 2) {
-	rb_warn("block supersedes default value argument");
+        rb_warn("block supersedes default value argument");
     }
     idx = NUM2LONG(pos);
 
     if (idx < 0) {
-	idx +=  RARRAY_LEN(ary);
+        idx +=  RARRAY_LEN(ary);
     }
     if (idx < 0 || RARRAY_LEN(ary) <= idx) {
-	if (block_given) return rb_yield(pos);
-	if (argc == 1) {
-	    rb_raise(rb_eIndexError, "index %ld outside of array bounds: %ld...%ld",
-			idx - (idx < 0 ? RARRAY_LEN(ary) : 0), -RARRAY_LEN(ary), RARRAY_LEN(ary));
-	}
-	return ifnone;
+        if (block_given) return rb_yield(pos);
+        if (argc == 1) {
+            rb_raise(rb_eIndexError, "index %ld outside of array bounds: %ld...%ld",
+                        idx - (idx < 0 ? RARRAY_LEN(ary) : 0), -RARRAY_LEN(ary), RARRAY_LEN(ary));
+        }
+        return ifnone;
     }
     return RARRAY_AREF(ary, idx);
 }
@@ -2086,6 +2201,7 @@ rb_ary_fetch(int argc, VALUE *argv, VALUE ary)
  *  When argument +object+ is given but no block,
  *  returns the index of the first element +element+
  *  for which <tt>object == element</tt>:
+ *
  *    a = [:foo, 'bar', 2, 'bar']
  *    a.index('bar') # => 1
  *
@@ -2094,12 +2210,14 @@ rb_ary_fetch(int argc, VALUE *argv, VALUE ary)
  *  When both argument +object+ and a block are given,
  *  calls the block with each successive element;
  *  returns the index of the first element for which the block returns a truthy value:
+ *
  *    a = [:foo, 'bar', 2, 'bar']
  *    a.index {|element| element == 'bar' } # => 1
  *
  *  Returns +nil+ if the block never returns a truthy value.
  *
  *  When neither an argument nor a block is given, returns a new Enumerator:
+ *
  *    a = [:foo, 'bar', 2]
  *    e = a.index
  *    e # => #<Enumerator: [:foo, "bar", 2]:index>
@@ -2117,23 +2235,23 @@ rb_ary_index(int argc, VALUE *argv, VALUE ary)
     long i;
 
     if (argc == 0) {
-	RETURN_ENUMERATOR(ary, 0, 0);
-	for (i=0; i<RARRAY_LEN(ary); i++) {
-	    if (RTEST(rb_yield(RARRAY_AREF(ary, i)))) {
-		return LONG2NUM(i);
-	    }
-	}
-	return Qnil;
+        RETURN_ENUMERATOR(ary, 0, 0);
+        for (i=0; i<RARRAY_LEN(ary); i++) {
+            if (RTEST(rb_yield(RARRAY_AREF(ary, i)))) {
+                return LONG2NUM(i);
+            }
+        }
+        return Qnil;
     }
     rb_check_arity(argc, 0, 1);
     val = argv[0];
     if (rb_block_given_p())
-	rb_warn("given block not used");
+        rb_warn("given block not used");
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	VALUE e = RARRAY_AREF(ary, i);
-	if (rb_equal(e, val)) {
-	    return LONG2NUM(i);
-	}
+        VALUE e = RARRAY_AREF(ary, i);
+        if (rb_equal(e, val)) {
+            return LONG2NUM(i);
+        }
     }
     return Qnil;
 }
@@ -2147,6 +2265,7 @@ rb_ary_index(int argc, VALUE *argv, VALUE ary)
  *  Returns the index of the last element for which <tt>object == element</tt>.
  *
  *  When argument +object+ is given but no block, returns the index of the last such element found:
+ *
  *    a = [:foo, 'bar', 2, 'bar']
  *    a.rindex('bar') # => 3
  *
@@ -2154,6 +2273,7 @@ rb_ary_index(int argc, VALUE *argv, VALUE ary)
  *
  *  When a block is given but no argument, calls the block with each successive element;
  *  returns the index of the last element for which the block returns a truthy value:
+ *
  *    a = [:foo, 'bar', 2, 'bar']
  *    a.rindex {|element| element == 'bar' } # => 3
  *
@@ -2176,25 +2296,25 @@ rb_ary_rindex(int argc, VALUE *argv, VALUE ary)
     long i = RARRAY_LEN(ary), len;
 
     if (argc == 0) {
-	RETURN_ENUMERATOR(ary, 0, 0);
-	while (i--) {
-	    if (RTEST(rb_yield(RARRAY_AREF(ary, i))))
-		return LONG2NUM(i);
-	    if (i > (len = RARRAY_LEN(ary))) {
-		i = len;
-	    }
-	}
-	return Qnil;
+        RETURN_ENUMERATOR(ary, 0, 0);
+        while (i--) {
+            if (RTEST(rb_yield(RARRAY_AREF(ary, i))))
+                return LONG2NUM(i);
+            if (i > (len = RARRAY_LEN(ary))) {
+                i = len;
+            }
+        }
+        return Qnil;
     }
     rb_check_arity(argc, 0, 1);
     val = argv[0];
     if (rb_block_given_p())
-	rb_warn("given block not used");
+        rb_warn("given block not used");
     while (i--) {
-	VALUE e = RARRAY_AREF(ary, i);
-	if (rb_equal(e, val)) {
-	    return LONG2NUM(i);
-	}
+        VALUE e = RARRAY_AREF(ary, i);
+        if (rb_equal(e, val)) {
+            return LONG2NUM(i);
+        }
         if (i > RARRAY_LEN(ary)) {
             break;
         }
@@ -2220,54 +2340,54 @@ rb_ary_splice(VALUE ary, long beg, long len, const VALUE *rptr, long rlen)
     if (len < 0) rb_raise(rb_eIndexError, "negative length (%ld)", len);
     olen = RARRAY_LEN(ary);
     if (beg < 0) {
-	beg += olen;
-	if (beg < 0) {
-	    rb_raise(rb_eIndexError, "index %ld too small for array; minimum: %ld",
-		     beg - olen, -olen);
-	}
+        beg += olen;
+        if (beg < 0) {
+            rb_raise(rb_eIndexError, "index %ld too small for array; minimum: %ld",
+                     beg - olen, -olen);
+        }
     }
     if (olen < len || olen < beg + len) {
-	len = olen - beg;
+        len = olen - beg;
     }
 
     {
         const VALUE *optr = RARRAY_CONST_PTR_TRANSIENT(ary);
-	rofs = (rptr >= optr && rptr < optr + olen) ? rptr - optr : -1;
+        rofs = (rptr >= optr && rptr < optr + olen) ? rptr - optr : -1;
     }
 
     if (beg >= olen) {
-	VALUE target_ary;
-	if (beg > ARY_MAX_SIZE - rlen) {
-	    rb_raise(rb_eIndexError, "index %ld too big", beg);
-	}
-	target_ary = ary_ensure_room_for_push(ary, rlen-len); /* len is 0 or negative */
-	len = beg + rlen;
-	ary_mem_clear(ary, olen, beg - olen);
-	if (rlen > 0) {
+        VALUE target_ary;
+        if (beg > ARY_MAX_SIZE - rlen) {
+            rb_raise(rb_eIndexError, "index %ld too big", beg);
+        }
+        target_ary = ary_ensure_room_for_push(ary, rlen-len); /* len is 0 or negative */
+        len = beg + rlen;
+        ary_mem_clear(ary, olen, beg - olen);
+        if (rlen > 0) {
             if (rofs != -1) rptr = RARRAY_CONST_PTR_TRANSIENT(ary) + rofs;
-	    ary_memcpy0(ary, beg, rlen, rptr, target_ary);
-	}
-	ARY_SET_LEN(ary, len);
+            ary_memcpy0(ary, beg, rlen, rptr, target_ary);
+        }
+        ARY_SET_LEN(ary, len);
     }
     else {
-	long alen;
-
-	if (olen - len > ARY_MAX_SIZE - rlen) {
-	    rb_raise(rb_eIndexError, "index %ld too big", olen + rlen - len);
-	}
-	rb_ary_modify(ary);
-	alen = olen + rlen - len;
-	if (alen >= ARY_CAPA(ary)) {
-	    ary_double_capa(ary, alen);
-	}
-
-	if (len != rlen) {
+        long alen;
+
+        if (olen - len > ARY_MAX_SIZE - rlen) {
+            rb_raise(rb_eIndexError, "index %ld too big", olen + rlen - len);
+        }
+        rb_ary_modify(ary);
+        alen = olen + rlen - len;
+        if (alen >= ARY_CAPA(ary)) {
+            ary_double_capa(ary, alen);
+        }
+
+        if (len != rlen) {
             RARRAY_PTR_USE_TRANSIENT(ary, ptr,
                                      MEMMOVE(ptr + beg + rlen, ptr + beg + len,
                                              VALUE, olen - (beg + len)));
-	    ARY_SET_LEN(ary, alen);
-	}
-	if (rlen > 0) {
+            ARY_SET_LEN(ary, alen);
+        }
+        if (rlen > 0) {
             if (rofs != -1) rptr = RARRAY_CONST_PTR_TRANSIENT(ary) + rofs;
             /* give up wb-protected ary */
             RB_OBJ_WB_UNPROTECT_FOR(ARRAY, ary);
@@ -2277,7 +2397,7 @@ rb_ary_splice(VALUE ary, long beg, long len, const VALUE *rptr, long rlen)
              */
             RARRAY_PTR_USE_TRANSIENT(ary, ptr,
                                      MEMMOVE(ptr + beg, rptr, VALUE, rlen));
-	}
+        }
     }
 }
 
@@ -2288,10 +2408,10 @@ rb_ary_set_len(VALUE ary, long len)
 
     rb_ary_modify_check(ary);
     if (ARY_SHARED_P(ary)) {
-	rb_raise(rb_eRuntimeError, "can't set length of shared ");
+        rb_raise(rb_eRuntimeError, "can't set length of shared ");
     }
     if (len > (capa = (long)ARY_CAPA(ary))) {
-	rb_bug("probable buffer overflow: %ld for %ld", len, capa);
+        rb_bug("probable buffer overflow: %ld for %ld", len, capa);
     }
     ARY_SET_LEN(ary, len);
 }
@@ -2305,14 +2425,14 @@ rb_ary_resize(VALUE ary, long len)
     olen = RARRAY_LEN(ary);
     if (len == olen) return ary;
     if (len > ARY_MAX_SIZE) {
-	rb_raise(rb_eIndexError, "index %ld too big", len);
+        rb_raise(rb_eIndexError, "index %ld too big", len);
     }
     if (len > olen) {
-	if (len >= ARY_CAPA(ary)) {
-	    ary_double_capa(ary, len);
-	}
-	ary_mem_clear(ary, olen, len - olen);
-	ARY_SET_LEN(ary, len);
+        if (len >= ARY_CAPA(ary)) {
+            ary_double_capa(ary, len);
+        }
+        ary_mem_clear(ary, olen, len - olen);
+        ARY_SET_LEN(ary, len);
     }
     else if (ARY_EMBED_P(ary)) {
         ARY_SET_EMBED_LEN(ary, len);
@@ -2331,11 +2451,11 @@ rb_ary_resize(VALUE ary, long len)
         if (is_malloc_ptr) ruby_sized_xfree((void *)ptr, ptr_capa);
     }
     else {
-	if (olen > len + ARY_DEFAULT_SIZE) {
+        if (olen > len + ARY_DEFAULT_SIZE) {
             size_t new_capa = ary_heap_realloc(ary, len);
             ARY_SET_CAPA(ary, new_capa);
-	}
-	ARY_SET_HEAP_LEN(ary, len);
+        }
+        ARY_SET_HEAP_LEN(ary, len);
     }
     ary_verify(ary);
     return ary;
@@ -2368,16 +2488,19 @@ ary_aset_by_rb_ary_splice(VALUE ary, long beg, long len, VALUE val)
  *  When \Integer argument +index+ is given, assigns +object+ to an element in +self+.
  *
  *  If +index+ is non-negative, assigns +object+ the element at offset +index+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[0] = 'foo' # => "foo"
  *    a # => ["foo", "bar", 2]
  *
  *  If +index+ is greater than <tt>self.length</tt>, extends the array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[7] = 'foo' # => "foo"
  *    a # => [:foo, "bar", 2, nil, nil, nil, nil, "foo"]
  *
  *  If +index+ is negative, counts backwards from the end of the array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[-1] = 'two' # => "two"
  *    a # => [:foo, "bar", "two"]
@@ -2385,11 +2508,13 @@ ary_aset_by_rb_ary_splice(VALUE ary, long beg, long len, VALUE val)
  *  When \Integer arguments +start+ and +length+ are given and +object+ is not an \Array,
  *  removes <tt>length - 1</tt> elements beginning at offset +start+,
  *  and assigns +object+ at offset +start+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[0, 2] = 'foo' # => "foo"
  *    a # => ["foo", 2]
  *
  *  If +start+ is negative, counts backwards from the end of the array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[-2, 2] = 'foo' # => "foo"
  *    a # => [:foo, "foo"]
@@ -2397,17 +2522,20 @@ ary_aset_by_rb_ary_splice(VALUE ary, long beg, long len, VALUE val)
  *  If +start+ is non-negative and outside the array (<tt> >= self.size</tt>),
  *  extends the array with +nil+, assigns +object+ at offset +start+,
  *  and ignores +length+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[6, 50] = 'foo' # => "foo"
  *    a # => [:foo, "bar", 2, nil, nil, nil, "foo"]
  *
  *  If +length+ is zero, shifts elements at and following offset +start+
  *  and assigns +object+ at offset +start+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[1, 0] = 'foo' # => "foo"
  *    a # => [:foo, "foo", "bar", 2]
  *
  *  If +length+ is too large for the existing array, does not extend the array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[1, 5] = 'foo' # => "foo"
  *    a # => [:foo, "foo"]
@@ -2415,29 +2543,34 @@ ary_aset_by_rb_ary_splice(VALUE ary, long beg, long len, VALUE val)
  *  When \Range argument +range+ is given and +object+ is an \Array,
  *  removes <tt>length - 1</tt> elements beginning at offset +start+,
  *  and assigns +object+ at offset +start+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[0..1] = 'foo' # => "foo"
  *    a # => ["foo", 2]
  *
  *  if <tt>range.begin</tt> is negative, counts backwards from the end of the array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[-2..2] = 'foo' # => "foo"
  *    a # => [:foo, "foo"]
  *
  *  If the array length is less than <tt>range.begin</tt>,
  *  assigns +object+ at offset <tt>range.begin</tt>, and ignores +length+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[6..50] = 'foo' # => "foo"
  *    a # => [:foo, "bar", 2, nil, nil, nil, "foo"]
  *
  *  If <tt>range.end</tt> is zero, shifts elements at and following offset +start+
  *  and assigns +object+ at offset +start+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[1..0] = 'foo' # => "foo"
  *    a # => [:foo, "foo", "bar", 2]
  *
  *  If <tt>range.end</tt> is negative, assigns +object+ at offset +start+,
  *  retains <tt>range.end.abs -1</tt> elements past that, and removes those beyond:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[1..-1] = 'foo' # => "foo"
  *    a # => [:foo, "foo"]
@@ -2451,9 +2584,11 @@ ary_aset_by_rb_ary_splice(VALUE ary, long beg, long len, VALUE val)
  *
  *  If <tt>range.end</tt> is too large for the existing array,
  *  replaces array elements, but does not extend the array with +nil+ values:
+ *
  *    a = [:foo, 'bar', 2]
  *    a[1..5] = 'foo' # => "foo"
  *    a # => [:foo, "foo"]
+ *
  */
 
 static VALUE
@@ -2464,16 +2599,16 @@ rb_ary_aset(int argc, VALUE *argv, VALUE ary)
     rb_check_arity(argc, 2, 3);
     rb_ary_modify_check(ary);
     if (argc == 3) {
-	beg = NUM2LONG(argv[0]);
-	len = NUM2LONG(argv[1]);
+        beg = NUM2LONG(argv[0]);
+        len = NUM2LONG(argv[1]);
         return ary_aset_by_rb_ary_splice(ary, beg, len, argv[2]);
     }
     if (FIXNUM_P(argv[0])) {
-	offset = FIX2LONG(argv[0]);
+        offset = FIX2LONG(argv[0]);
         return ary_aset_by_rb_ary_store(ary, offset, argv[1]);
     }
     if (rb_range_beg_len(argv[0], &beg, &len, RARRAY_LEN(ary), 1)) {
-	/* check if idx is Range */
+        /* check if idx is Range */
         return ary_aset_by_rb_ary_splice(ary, beg, len, argv[1]);
     }
 
@@ -2490,15 +2625,18 @@ rb_ary_aset(int argc, VALUE *argv, VALUE ary)
  *
  *  When +index+ is non-negative, inserts all given +objects+
  *  before the element at offset +index+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.insert(1, :bat, :bam) # => [:foo, :bat, :bam, "bar", 2]
  *
  *  Extends the array if +index+ is beyond the array (<tt>index >= self.size</tt>):
+ *
  *    a = [:foo, 'bar', 2]
  *    a.insert(5, :bat, :bam)
  *    a # => [:foo, "bar", 2, nil, nil, :bat, :bam]
  *
  *  Does nothing if no objects given:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.insert(1)
  *    a.insert(50)
@@ -2507,9 +2645,11 @@ rb_ary_aset(int argc, VALUE *argv, VALUE ary)
  *
  *  When +index+ is negative, inserts all given +objects+
  *  _after_ the element at offset <tt>index+self.size</tt>:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.insert(-2, :bat, :bam)
  *    a # => [:foo, "bar", :bat, :bam, 2]
+ *
  */
 
 static VALUE
@@ -2522,15 +2662,15 @@ rb_ary_insert(int argc, VALUE *argv, VALUE ary)
     pos = NUM2LONG(argv[0]);
     if (argc == 1) return ary;
     if (pos == -1) {
-	pos = RARRAY_LEN(ary);
+        pos = RARRAY_LEN(ary);
     }
     else if (pos < 0) {
-	long minpos = -RARRAY_LEN(ary) - 1;
-	if (pos < minpos) {
-	    rb_raise(rb_eIndexError, "index %ld too small for array; minimum: %ld",
-		     pos, minpos);
-	}
-	pos++;
+        long minpos = -RARRAY_LEN(ary) - 1;
+        if (pos < minpos) {
+            rb_raise(rb_eIndexError, "index %ld too small for array; minimum: %ld",
+                     pos, minpos);
+        }
+        pos++;
     }
     rb_ary_splice(ary, pos, 0, argv + 1, argc - 1);
     return ary;
@@ -2554,29 +2694,35 @@ ary_enum_length(VALUE ary, VALUE args, VALUE eobj)
  *
  *  When a block given, passes each successive array element to the block;
  *  returns +self+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.each {|element|  puts "#{element.class} #{element}" }
  *
  *  Output:
+ *
  *    Symbol foo
  *    String bar
  *    Integer 2
  *
  *  Allows the array to be modified during iteration:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.each {|element| puts element; a.clear if element.to_s.start_with?('b') }
  *
  *  Output:
+ *
  *    foo
  *    bar
  *
  *  When no block given, returns a new \Enumerator:
  *    a = [:foo, 'bar', 2]
+ *
  *    e = a.each
  *    e # => #<Enumerator: [:foo, "bar", 2]:each>
  *    a1 = e.each {|element|  puts "#{element.class} #{element}" }
  *
  *  Output:
+ *
  *    Symbol foo
  *    String bar
  *    Integer 2
@@ -2591,7 +2737,7 @@ rb_ary_each(VALUE ary)
     ary_verify(ary);
     RETURN_SIZED_ENUMERATOR(ary, 0, 0, ary_enum_length);
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	rb_yield(RARRAY_AREF(ary, i));
+        rb_yield(RARRAY_AREF(ary, i));
     }
     return ary;
 }
@@ -2605,29 +2751,35 @@ rb_ary_each(VALUE ary)
  *
  *  When a block given, passes each successive array index to the block;
  *  returns +self+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.each_index {|index|  puts "#{index} #{a[index]}" }
  *
  *  Output:
+ *
  *    0 foo
  *    1 bar
  *    2 2
  *
  *  Allows the array to be modified during iteration:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.each_index {|index| puts index; a.clear if index > 0 }
  *
  *  Output:
+ *
  *    0
  *    1
  *
  *  When no block given, returns a new \Enumerator:
+ *
  *    a = [:foo, 'bar', 2]
  *    e = a.each_index
  *    e # => #<Enumerator: [:foo, "bar", 2]:each_index>
  *    a1 = e.each {|index|  puts "#{index} #{a[index]}"}
  *
  *  Output:
+ *
  *    0 foo
  *    1 bar
  *    2 2
@@ -2642,7 +2794,7 @@ rb_ary_each_index(VALUE ary)
     RETURN_SIZED_ENUMERATOR(ary, 0, 0, ary_enum_length);
 
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	rb_yield(LONG2NUM(i));
+        rb_yield(LONG2NUM(i));
     }
     return ary;
 }
@@ -2656,28 +2808,35 @@ rb_ary_each_index(VALUE ary)
  *
  *  When a block given, passes, in reverse order, each element to the block;
  *  returns +self+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.reverse_each {|element|  puts "#{element.class} #{element}" }
  *
  *  Output:
+ *
  *    Integer 2
  *    String bar
  *    Symbol foo
  *
  *  Allows the array to be modified during iteration:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.reverse_each {|element| puts element; a.clear if element.to_s.start_with?('b') }
  *
  *  Output:
+ *
  *    2
  *    bar
  *
  *  When no block given, returns a new \Enumerator:
+ *
  *    a = [:foo, 'bar', 2]
  *    e = a.reverse_each
  *    e # => #<Enumerator: [:foo, "bar", 2]:reverse_each>
  *    a1 = e.each {|element|  puts "#{element.class} #{element}" }
+ *
  *  Output:
+ *
  *    Integer 2
  *    String bar
  *    Symbol foo
@@ -2693,12 +2852,12 @@ rb_ary_reverse_each(VALUE ary)
     RETURN_SIZED_ENUMERATOR(ary, 0, 0, ary_enum_length);
     len = RARRAY_LEN(ary);
     while (len--) {
-	long nlen;
-	rb_yield(RARRAY_AREF(ary, len));
-	nlen = RARRAY_LEN(ary);
-	if (nlen < len) {
-	    len = nlen;
-	}
+        long nlen;
+        rb_yield(RARRAY_AREF(ary, len));
+        nlen = RARRAY_LEN(ary);
+        if (nlen < len) {
+            len = nlen;
+        }
     }
     return ary;
 }
@@ -2764,10 +2923,10 @@ recursive_join(VALUE obj, VALUE argp, int recur)
     int *first = (int *)arg[3];
 
     if (recur) {
-	rb_raise(rb_eArgError, "recursive array join");
+        rb_raise(rb_eArgError, "recursive array join");
     }
     else {
-	ary_join_1(obj, ary, sep, 0, result, first);
+        ary_join_1(obj, ary, sep, 0, result, first);
     }
     return Qnil;
 }
@@ -2780,11 +2939,11 @@ ary_join_0(VALUE ary, VALUE sep, long max, VALUE result)
 
     if (max > 0) rb_enc_copy(result, RARRAY_AREF(ary, 0));
     for (i=0; i<max; i++) {
-	val = RARRAY_AREF(ary, i);
+        val = RARRAY_AREF(ary, i);
         if (!RB_TYPE_P(val, T_STRING)) break;
-	if (i > 0 && !NIL_P(sep))
-	    rb_str_buf_append(result, sep);
-	rb_str_buf_append(result, val);
+        if (i > 0 && !NIL_P(sep))
+            rb_str_buf_append(result, sep);
+        rb_str_buf_append(result, val);
     }
     return i;
 }
@@ -2823,16 +2982,16 @@ ary_join_1(VALUE obj, VALUE ary, VALUE sep, long i, VALUE result, int *first)
     VALUE val, tmp;
 
     for (; i<RARRAY_LEN(ary); i++) {
-	if (i > 0 && !NIL_P(sep))
-	    rb_str_buf_append(result, sep);
+        if (i > 0 && !NIL_P(sep))
+            rb_str_buf_append(result, sep);
 
-	val = RARRAY_AREF(ary, i);
-	if (RB_TYPE_P(val, T_STRING)) {
+        val = RARRAY_AREF(ary, i);
+        if (RB_TYPE_P(val, T_STRING)) {
             ary_join_1_str(result, val, first);
-	}
-	else if (RB_TYPE_P(val, T_ARRAY)) {
+        }
+        else if (RB_TYPE_P(val, T_ARRAY)) {
             ary_join_1_ary(val, ary, sep, result, val, first);
-	}
+        }
         else if (!NIL_P(tmp = rb_check_string_type(val))) {
             ary_join_1_str(result, tmp, first);
         }
@@ -2841,7 +3000,7 @@ ary_join_1(VALUE obj, VALUE ary, VALUE sep, long i, VALUE result, int *first)
         }
         else {
             ary_join_1_str(result, rb_obj_as_string(val), first);
-	}
+        }
     }
 }
 
@@ -2854,26 +3013,26 @@ rb_ary_join(VALUE ary, VALUE sep)
     if (RARRAY_LEN(ary) == 0) return rb_usascii_str_new(0, 0);
 
     if (!NIL_P(sep)) {
-	StringValue(sep);
-	len += RSTRING_LEN(sep) * (RARRAY_LEN(ary) - 1);
+        StringValue(sep);
+        len += RSTRING_LEN(sep) * (RARRAY_LEN(ary) - 1);
     }
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	val = RARRAY_AREF(ary, i);
-	tmp = rb_check_string_type(val);
+        val = RARRAY_AREF(ary, i);
+        tmp = rb_check_string_type(val);
 
-	if (NIL_P(tmp) || tmp != val) {
-	    int first;
+        if (NIL_P(tmp) || tmp != val) {
+            int first;
             long n = RARRAY_LEN(ary);
             if (i > n) i = n;
             result = rb_str_buf_new(len + (n-i)*10);
-	    rb_enc_associate(result, rb_usascii_encoding());
+            rb_enc_associate(result, rb_usascii_encoding());
             i = ary_join_0(ary, sep, i, result);
-	    first = i == 0;
-	    ary_join_1(ary, ary, sep, i, result, &first);
-	    return result;
-	}
+            first = i == 0;
+            ary_join_1(ary, ary, sep, i, result, &first);
+            return result;
+        }
 
-	len += RSTRING_LEN(tmp);
+        len += RSTRING_LEN(tmp);
     }
 
     result = rb_str_new(0, len);
@@ -2890,22 +3049,27 @@ rb_ary_join(VALUE ary, VALUE sep)
  *    array.join(separator = $,) -> new_string
  *
  *  Returns the new \String formed by joining the array elements after conversion.
- *  For each element +element+
+ *  For each element +element+:
+ *
  *  - Uses <tt>element.to_s</tt> if +element+ is not a <tt>kind_of?(Array)</tt>.
  *  - Uses recursive <tt>element.join(separator)</tt> if +element+ is a <tt>kind_of?(Array)</tt>.
  *
  *  With no argument, joins using the output field separator, <tt>$,</tt>:
+ *
  *    a = [:foo, 'bar', 2]
  *    $, # => nil
  *    a.join # => "foobar2"
  *
  *  With \string argument +separator+, joins using that separator:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.join("\n") # => "foo\nbar\n2"
  *
  *  Joins recursively for nested Arrays:
+ *
  *   a = [:foo, [:bar, [:baz, :bat]]]
  *   a.join # => "foobarbazbat"
+ *
  */
 static VALUE
 rb_ary_join_m(int argc, VALUE *argv, VALUE ary)
@@ -2931,10 +3095,10 @@ inspect_ary(VALUE ary, VALUE dummy, int recur)
     if (recur) return rb_usascii_str_new_cstr("[...]");
     str = rb_str_buf_new2("[");
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	s = rb_inspect(RARRAY_AREF(ary, i));
-	if (i > 0) rb_str_buf_cat2(str, ", ");
-	else rb_enc_copy(str, s);
-	rb_str_buf_append(str, s);
+        s = rb_inspect(RARRAY_AREF(ary, i));
+        if (i > 0) rb_str_buf_cat2(str, ", ");
+        else rb_enc_copy(str, s);
+        rb_str_buf_append(str, s);
     }
     rb_str_buf_cat2(str, "]");
     return str;
@@ -2946,6 +3110,7 @@ inspect_ary(VALUE ary, VALUE dummy, int recur)
  *
  *  Returns the new \String formed by calling method <tt>#inspect</tt>
  *  on each array element:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.inspect # => "[:foo, \"bar\", 2]"
  *
@@ -2970,10 +3135,12 @@ rb_ary_to_s(VALUE ary)
  *    to_a -> self or new_array
  *
  *  When +self+ is an instance of \Array, returns +self+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.to_a # => [:foo, "bar", 2]
  *
  *  Otherwise, returns a new \Array containing the elements of +self+:
+ *
  *    class MyArray < Array; end
  *    a = MyArray.new(['foo', 'bar', 'two'])
  *    a.instance_of?(Array) # => false
@@ -2981,15 +3148,16 @@ rb_ary_to_s(VALUE ary)
  *    a1 = a.to_a
  *    a1 # => ["foo", "bar", "two"]
  *    a1.class # => Array # Not MyArray
+ *
  */
 
 static VALUE
 rb_ary_to_a(VALUE ary)
 {
     if (rb_obj_class(ary) != rb_cArray) {
-	VALUE dup = rb_ary_new2(RARRAY_LEN(ary));
-	rb_ary_replace(dup, ary);
-	return dup;
+        VALUE dup = rb_ary_new2(RARRAY_LEN(ary));
+        rb_ary_replace(dup, ary);
+        return dup;
     }
     return ary;
 }
@@ -3004,16 +3172,19 @@ rb_ary_to_a(VALUE ary)
  *  When a block is given, calls the block with each array element;
  *  the block must return a 2-element \Array whose two elements
  *  form a key-value pair in the returned \Hash:
+ *
  *    a = ['foo', :bar, 1, [2, 3], {baz: 4}]
  *    h = a.to_h {|item| [item, item] }
  *    h # => {"foo"=>"foo", :bar=>:bar, 1=>1, [2, 3]=>[2, 3], {:baz=>4}=>{:baz=>4}}
  *
  *  When no block is given, +self+ must be an \Array of 2-element sub-arrays,
  *  each sub-array is formed into a key-value pair in the new \Hash:
+ *
  *    [].to_h # => {}
  *    a = [['foo', 'zero'], ['bar', 'one'], ['baz', 'two']]
  *    h = a.to_h
  *    h # => {"foo"=>"zero", "bar"=>"one", "baz"=>"two"}
+ *
  */
 
 static VALUE
@@ -3024,18 +3195,18 @@ rb_ary_to_h(VALUE ary)
     int block_given = rb_block_given_p();
 
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	const VALUE e = rb_ary_elt(ary, i);
-	const VALUE elt = block_given ? rb_yield_force_blockarg(e) : e;
-	const VALUE key_value_pair = rb_check_array_type(elt);
-	if (NIL_P(key_value_pair)) {
-	    rb_raise(rb_eTypeError, "wrong element type %"PRIsVALUE" at %ld (expected array)",
-		     rb_obj_class(elt), i);
-	}
-	if (RARRAY_LEN(key_value_pair) != 2) {
-	    rb_raise(rb_eArgError, "wrong array length at %ld (expected 2, was %ld)",
-		i, RARRAY_LEN(key_value_pair));
-	}
-	rb_hash_aset(hash, RARRAY_AREF(key_value_pair, 0), RARRAY_AREF(key_value_pair, 1));
+        const VALUE e = rb_ary_elt(ary, i);
+        const VALUE elt = block_given ? rb_yield_force_blockarg(e) : e;
+        const VALUE key_value_pair = rb_check_array_type(elt);
+        if (NIL_P(key_value_pair)) {
+            rb_raise(rb_eTypeError, "wrong element type %"PRIsVALUE" at %ld (expected array)",
+                     rb_obj_class(elt), i);
+        }
+        if (RARRAY_LEN(key_value_pair) != 2) {
+            rb_raise(rb_eArgError, "wrong array length at %ld (expected 2, was %ld)",
+                i, RARRAY_LEN(key_value_pair));
+        }
+        rb_hash_aset(hash, RARRAY_AREF(key_value_pair, 0), RARRAY_AREF(key_value_pair, 1));
     }
     return hash;
 }
@@ -3057,9 +3228,9 @@ static void
 ary_reverse(VALUE *p1, VALUE *p2)
 {
     while (p1 < p2) {
-	VALUE tmp = *p1;
-	*p1++ = *p2;
-	*p2-- = tmp;
+        VALUE tmp = *p1;
+        *p1++ = *p2;
+        *p2-- = tmp;
     }
 }
 
@@ -3074,7 +3245,7 @@ rb_ary_reverse(VALUE ary)
         RARRAY_PTR_USE_TRANSIENT(ary, p1, {
             p2 = p1 + len - 1;	/* points last item */
             ary_reverse(p1, p2);
-	}); /* WB: no new reference */
+        }); /* WB: no new reference */
     }
     return ary;
 }
@@ -3084,8 +3255,10 @@ rb_ary_reverse(VALUE ary)
  *    array.reverse! -> self
  *
  *  Reverses +self+ in place:
+ *
  *    a = ['foo', 'bar', 'two']
  *    a.reverse! # => ["two", "bar", "foo"]
+ *
  */
 
 static VALUE
@@ -3098,10 +3271,12 @@ rb_ary_reverse_bang(VALUE ary)
  *  call-seq:
  *    array.reverse -> new_array
  *
- *  Returns a new \Array with the elements of +self+ in reverse order.
+ *  Returns a new \Array with the elements of +self+ in reverse order:
+ *
  *    a = ['foo', 'bar', 'two']
  *    a1 = a.reverse
  *    a1 # => ["two", "bar", "foo"]
+ *
  */
 
 static VALUE
@@ -3113,7 +3288,7 @@ rb_ary_reverse_m(VALUE ary)
     if (len > 0) {
         const VALUE *p1 = RARRAY_CONST_PTR_TRANSIENT(ary);
         VALUE *p2 = (VALUE *)RARRAY_CONST_PTR_TRANSIENT(dup) + len - 1;
-	do *p2-- = *p1++; while (--len > 0);
+        do *p2-- = *p1++; while (--len > 0);
     }
     ARY_SET_LEN(dup, RARRAY_LEN(ary));
     return dup;
@@ -3169,35 +3344,42 @@ rb_ary_rotate(VALUE ary, long cnt)
  *  Rotates +self+ in place by moving elements from one end to the other; returns +self+.
  *
  *  When no argument given, rotates the first element to the last position:
+ *
  *    a = [:foo, 'bar', 2, 'bar']
  *    a.rotate! # => ["bar", 2, "bar", :foo]
  *
  *  When given a non-negative \Integer +count+,
  *  rotates +count+ elements from the beginning to the end:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.rotate!(2)
  *    a # => [2, :foo, "bar"]
  *
  *  If +count+ is large, uses <tt>count % array.size</tt> as the count:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.rotate!(20)
  *    a # => [2, :foo, "bar"]
  *
  *  If +count+ is zero, returns +self+ unmodified:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.rotate!(0)
  *    a # => [:foo, "bar", 2]
  *
  *  When given a negative Integer +count+, rotates in the opposite direction,
  *  from end to beginning:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.rotate!(-2)
  *    a # => ["bar", 2, :foo]
  *
  *  If +count+ is small (far from zero), uses <tt>count % array.size</tt> as the count:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.rotate!(-5)
  *    a # => ["bar", 2, :foo]
+ *
  */
 
 static VALUE
@@ -3218,36 +3400,43 @@ rb_ary_rotate_bang(int argc, VALUE *argv, VALUE ary)
  *
  *  When no argument given, returns a new \Array that is like +self+,
  *  except that the first element has been rotated to the last position:
+ *
  *    a = [:foo, 'bar', 2, 'bar']
  *    a1 = a.rotate
  *    a1 # => ["bar", 2, "bar", :foo]
  *
  *  When given a non-negative \Integer +count+,
  *  returns a new \Array with +count+ elements rotated from the beginning to the end:
+ *
  *    a = [:foo, 'bar', 2]
  *    a1 = a.rotate(2)
  *    a1 # => [2, :foo, "bar"]
  *
  *  If +count+ is large, uses <tt>count % array.size</tt> as the count:
+ *
  *    a = [:foo, 'bar', 2]
  *    a1 = a.rotate(20)
  *    a1 # => [2, :foo, "bar"]
  *
  *  If +count+ is zero, returns a copy of +self+, unmodified:
+ *
  *    a = [:foo, 'bar', 2]
  *    a1 = a.rotate(0)
  *    a1 # => [:foo, "bar", 2]
  *
  *  When given a negative \Integer +count+, rotates in the opposite direction,
  *  from end to beginning:
+ *
  *    a = [:foo, 'bar', 2]
  *    a1 = a.rotate(-2)
  *    a1 # => ["bar", 2, :foo]
  *
  *  If +count+ is small (far from zero), uses <tt>count % array.size</tt> as the count:
+ *
  *    a = [:foo, 'bar', 2]
  *    a1 = a.rotate(-5)
  *    a1 # => ["bar", 2, :foo]
+ *
  */
 
 static VALUE
@@ -3261,11 +3450,11 @@ rb_ary_rotate_m(int argc, VALUE *argv, VALUE ary)
     len = RARRAY_LEN(ary);
     rotated = rb_ary_new2(len);
     if (len > 0) {
-	cnt = rotate_count(cnt, len);
+        cnt = rotate_count(cnt, len);
         ptr = RARRAY_CONST_PTR_TRANSIENT(ary);
-	len -= cnt;
-	ary_memcpy(rotated, 0, len, ptr + cnt);
-	ary_memcpy(rotated, len, cnt, ptr);
+        len -= cnt;
+        ary_memcpy(rotated, 0, len, ptr + cnt);
+        ary_memcpy(rotated, len, cnt, ptr);
     }
     ARY_SET_LEN(rotated, RARRAY_LEN(ary));
     return rotated;
@@ -3274,14 +3463,13 @@ rb_ary_rotate_m(int argc, VALUE *argv, VALUE ary)
 struct ary_sort_data {
     VALUE ary;
     VALUE receiver;
-    struct cmp_opt_data cmp_opt;
 };
 
 static VALUE
 sort_reentered(VALUE ary)
 {
     if (RBASIC(ary)->klass) {
-	rb_raise(rb_eRuntimeError, "sort reentered");
+        rb_raise(rb_eRuntimeError, "sort reentered");
     }
     return Qnil;
 }
@@ -3320,16 +3508,16 @@ sort_2(const void *ap, const void *bp, void *dummy)
     VALUE a = *(const VALUE *)ap, b = *(const VALUE *)bp;
     int n;
 
-    if (FIXNUM_P(a) && FIXNUM_P(b) && CMP_OPTIMIZABLE(data->cmp_opt, Integer)) {
-	if ((long)a > (long)b) return 1;
-	if ((long)a < (long)b) return -1;
-	return 0;
+    if (FIXNUM_P(a) && FIXNUM_P(b) && CMP_OPTIMIZABLE(INTEGER)) {
+        if ((long)a > (long)b) return 1;
+        if ((long)a < (long)b) return -1;
+        return 0;
     }
-    if (STRING_P(a) && STRING_P(b) && CMP_OPTIMIZABLE(data->cmp_opt, String)) {
-	return rb_str_cmp(a, b);
+    if (STRING_P(a) && STRING_P(b) && CMP_OPTIMIZABLE(STRING)) {
+        return rb_str_cmp(a, b);
     }
-    if (RB_FLOAT_TYPE_P(a) && CMP_OPTIMIZABLE(data->cmp_opt, Float)) {
-	return rb_float_cmp(a, b);
+    if (RB_FLOAT_TYPE_P(a) && CMP_OPTIMIZABLE(FLOAT)) {
+        return rb_float_cmp(a, b);
     }
 
     retval = rb_funcallv(a, id_cmp, 1, &b);
@@ -3348,6 +3536,7 @@ sort_2(const void *ap, const void *bp, void *dummy)
  *
  *  With no block, compares elements using operator <tt><=></tt>
  *  (see Comparable):
+ *
  *    a = 'abcde'.split('').shuffle
  *    a # => ["e", "b", "d", "a", "c"]
  *    a.sort!
@@ -3355,11 +3544,13 @@ sort_2(const void *ap, const void *bp, void *dummy)
  *
  *  With a block, calls the block with each element pair;
  *  for each element pair +a+ and +b+, the block should return an integer:
+ *
  *  - Negative when +b+ is to follow +a+.
  *  - Zero when +a+ and +b+ are equivalent.
  *  - Positive when +a+ is to follow +b+.
  *
  *  Example:
+ *
  *    a = 'abcde'.split('').shuffle
  *    a # => ["e", "b", "d", "a", "c"]
  *    a.sort! {|a, b| a <=> b }
@@ -3369,10 +3560,12 @@ sort_2(const void *ap, const void *bp, void *dummy)
  *
  *  When the block returns zero, the order for +a+ and +b+ is indeterminate,
  *  and may be unstable:
+ *
  *    a = 'abcde'.split('').shuffle
  *    a # => ["e", "b", "d", "a", "c"]
  *    a.sort! {|a, b| 0 }
  *    a # => ["d", "e", "c", "a", "b"]
+ *
  */
 
 VALUE
@@ -3381,25 +3574,23 @@ rb_ary_sort_bang(VALUE ary)
     rb_ary_modify(ary);
     assert(!ARY_SHARED_P(ary));
     if (RARRAY_LEN(ary) > 1) {
-	VALUE tmp = ary_make_substitution(ary); /* only ary refers tmp */
-	struct ary_sort_data data;
-	long len = RARRAY_LEN(ary);
-	RBASIC_CLEAR_CLASS(tmp);
-	data.ary = tmp;
+        VALUE tmp = ary_make_substitution(ary); /* only ary refers tmp */
+        struct ary_sort_data data;
+        long len = RARRAY_LEN(ary);
+        RBASIC_CLEAR_CLASS(tmp);
+        data.ary = tmp;
         data.receiver = ary;
-	data.cmp_opt.opt_methods = 0;
-	data.cmp_opt.opt_inited = 0;
-	RARRAY_PTR_USE(tmp, ptr, {
+        RARRAY_PTR_USE(tmp, ptr, {
             ruby_qsort(ptr, len, sizeof(VALUE),
                        rb_block_given_p()?sort_1:sort_2, &data);
-	}); /* WB: no new reference */
-	rb_ary_modify(ary);
+        }); /* WB: no new reference */
+        rb_ary_modify(ary);
         if (ARY_EMBED_P(tmp)) {
             if (ARY_SHARED_P(ary)) { /* ary might be destructively operated in the given block */
                 rb_ary_unshare(ary);
-		FL_SET_EMBED(ary);
+                FL_SET_EMBED(ary);
             }
-	    ary_memcpy(ary, 0, ARY_EMBED_LEN(tmp), ARY_EMBED_PTR(tmp));
+            ary_memcpy(ary, 0, ARY_EMBED_LEN(tmp), ARY_EMBED_PTR(tmp));
             ARY_SET_LEN(ary, ARY_EMBED_LEN(tmp));
         }
         else {
@@ -3445,6 +3636,7 @@ rb_ary_sort_bang(VALUE ary)
  *
  *  With no block, compares elements using operator <tt><=></tt>
  *  (see Comparable):
+ *
  *    a = 'abcde'.split('').shuffle
  *    a # => ["e", "b", "d", "a", "c"]
  *    a1 = a.sort
@@ -3452,11 +3644,13 @@ rb_ary_sort_bang(VALUE ary)
  *
  *  With a block, calls the block with each element pair;
  *  for each element pair +a+ and +b+, the block should return an integer:
+ *
  *  - Negative when +b+ is to follow +a+.
  *  - Zero when +a+ and +b+ are equivalent.
  *  - Positive when +a+ is to follow +b+.
  *
  *  Example:
+ *
  *    a = 'abcde'.split('').shuffle
  *    a # => ["e", "b", "d", "a", "c"]
  *    a1 = a.sort {|a, b| a <=> b }
@@ -3466,6 +3660,7 @@ rb_ary_sort_bang(VALUE ary)
  *
  *  When the block returns zero, the order for +a+ and +b+ is indeterminate,
  *  and may be unstable:
+ *
  *    a = 'abcde'.split('').shuffle
  *    a # => ["e", "b", "d", "a", "c"]
  *    a1 = a.sort {|a, b| 0 }
@@ -3500,7 +3695,7 @@ rb_ary_bsearch(VALUE ary)
     VALUE index_result = rb_ary_bsearch_index(ary);
 
     if (FIXNUM_P(index_result)) {
-	return rb_ary_entry(ary, FIX2LONG(index_result));
+        return rb_ary_entry(ary, FIX2LONG(index_result));
     }
     return index_result;
 }
@@ -3523,39 +3718,39 @@ rb_ary_bsearch_index(VALUE ary)
 
     RETURN_ENUMERATOR(ary, 0, 0);
     while (low < high) {
-	mid = low + ((high - low) / 2);
-	val = rb_ary_entry(ary, mid);
-	v = rb_yield(val);
-	if (FIXNUM_P(v)) {
-	    if (v == INT2FIX(0)) return INT2FIX(mid);
-	    smaller = (SIGNED_VALUE)v < 0; /* Fixnum preserves its sign-bit */
-	}
-	else if (v == Qtrue) {
-	    satisfied = 1;
-	    smaller = 1;
-	}
-	else if (!RTEST(v)) {
-	    smaller = 0;
-	}
-	else if (rb_obj_is_kind_of(v, rb_cNumeric)) {
-	    const VALUE zero = INT2FIX(0);
-	    switch (rb_cmpint(rb_funcallv(v, id_cmp, 1, &zero), v, zero)) {
-	      case 0: return INT2FIX(mid);
-	      case 1: smaller = 1; break;
-	      case -1: smaller = 0;
-	    }
-	}
-	else {
-	    rb_raise(rb_eTypeError, "wrong argument type %"PRIsVALUE
-		     " (must be numeric, true, false or nil)",
-		     rb_obj_class(v));
-	}
-	if (smaller) {
-	    high = mid;
-	}
-	else {
-	    low = mid + 1;
-	}
+        mid = low + ((high - low) / 2);
+        val = rb_ary_entry(ary, mid);
+        v = rb_yield(val);
+        if (FIXNUM_P(v)) {
+            if (v == INT2FIX(0)) return INT2FIX(mid);
+            smaller = (SIGNED_VALUE)v < 0; /* Fixnum preserves its sign-bit */
+        }
+        else if (v == Qtrue) {
+            satisfied = 1;
+            smaller = 1;
+        }
+        else if (!RTEST(v)) {
+            smaller = 0;
+        }
+        else if (rb_obj_is_kind_of(v, rb_cNumeric)) {
+            const VALUE zero = INT2FIX(0);
+            switch (rb_cmpint(rb_funcallv(v, id_cmp, 1, &zero), v, zero)) {
+              case 0: return INT2FIX(mid);
+              case 1: smaller = 0; break;
+              case -1: smaller = 1;
+            }
+        }
+        else {
+            rb_raise(rb_eTypeError, "wrong argument type %"PRIsVALUE
+                     " (must be numeric, true, false or nil)",
+                     rb_obj_class(v));
+        }
+        if (smaller) {
+            high = mid;
+        }
+        else {
+            low = mid + 1;
+        }
     }
     if (!satisfied) return Qnil;
     return INT2FIX(low);
@@ -3582,6 +3777,7 @@ sort_by_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, dummy))
  *  For duplicates returned by the block, the ordering is indeterminate, and may be unstable.
  *
  *  This example sorts strings based on their sizes:
+ *
  *    a = ['aaaa', 'bbb', 'cc', 'd']
  *    a.sort_by! {|element| element.size }
  *    a # => ["d", "cc", "bbb", "aaaa"]
@@ -3590,6 +3786,7 @@ sort_by_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, dummy))
  *
  *    a = ['aaaa', 'bbb', 'cc', 'd']
  *    a.sort_by! # => #<Enumerator: ["aaaa", "bbb", "cc", "d"]:sort_by!>
+ *
  */
 
 static VALUE
@@ -3612,6 +3809,7 @@ rb_ary_sort_by_bang(VALUE ary)
  *
  *  Calls the block, if given, with each element of +self+;
  *  returns a new \Array whose elements are the return values from the block:
+ *
  *    a = [:foo, 'bar', 2]
  *    a1 = a.map {|element| element.class }
  *    a1 # => [Symbol, String, Integer]
@@ -3646,10 +3844,12 @@ rb_ary_collect(VALUE ary)
  *
  *  Calls the block, if given, with each element;
  *  replaces the element with the block's return value:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.map! { |element| element.class } # => [Symbol, String, Integer]
  *
  *  Returns a new \Enumerator if no block given:
+ *
  *    a = [:foo, 'bar', 2]
  *    a1 = a.map!
  *    a1 # => #<Enumerator: [:foo, "bar", 2]:map!>
@@ -3665,7 +3865,7 @@ rb_ary_collect_bang(VALUE ary)
     RETURN_SIZED_ENUMERATOR(ary, 0, 0, ary_enum_length);
     rb_ary_modify(ary);
     for (i = 0; i < RARRAY_LEN(ary); i++) {
-	rb_ary_store(ary, i, rb_yield(RARRAY_AREF(ary, i)));
+        rb_ary_store(ary, i, rb_yield(RARRAY_AREF(ary, i)));
     }
     return ary;
 }
@@ -3677,21 +3877,21 @@ rb_get_values_at(VALUE obj, long olen, int argc, const VALUE *argv, VALUE (*func
     long beg, len, i, j;
 
     for (i=0; i<argc; i++) {
-	if (FIXNUM_P(argv[i])) {
-	    rb_ary_push(result, (*func)(obj, FIX2LONG(argv[i])));
-	    continue;
-	}
-	/* check if idx is Range */
-	if (rb_range_beg_len(argv[i], &beg, &len, olen, 1)) {
-	    long end = olen < beg+len ? olen : beg+len;
-	    for (j = beg; j < end; j++) {
-		rb_ary_push(result, (*func)(obj, j));
-	    }
-	    if (beg + len > j)
-		rb_ary_resize(result, RARRAY_LEN(result) + (beg + len) - j);
-	    continue;
-	}
-	rb_ary_push(result, (*func)(obj, NUM2LONG(argv[i])));
+        if (FIXNUM_P(argv[i])) {
+            rb_ary_push(result, (*func)(obj, FIX2LONG(argv[i])));
+            continue;
+        }
+        /* check if idx is Range */
+        if (rb_range_beg_len(argv[i], &beg, &len, olen, 1)) {
+            long end = olen < beg+len ? olen : beg+len;
+            for (j = beg; j < end; j++) {
+                rb_ary_push(result, (*func)(obj, j));
+            }
+            if (beg + len > j)
+                rb_ary_resize(result, RARRAY_LEN(result) + (beg + len) - j);
+            continue;
+        }
+        rb_ary_push(result, (*func)(obj, NUM2LONG(argv[i])));
     }
     return result;
 }
@@ -3701,25 +3901,25 @@ append_values_at_single(VALUE result, VALUE ary, long olen, VALUE idx)
 {
     long beg, len;
     if (FIXNUM_P(idx)) {
-	beg = FIX2LONG(idx);
+        beg = FIX2LONG(idx);
     }
     /* check if idx is Range */
     else if (rb_range_beg_len(idx, &beg, &len, olen, 1)) {
-	if (len > 0) {
+        if (len > 0) {
             const VALUE *const src = RARRAY_CONST_PTR_TRANSIENT(ary);
-	    const long end = beg + len;
-	    const long prevlen = RARRAY_LEN(result);
-	    if (beg < olen) {
-		rb_ary_cat(result, src + beg, end > olen ? olen-beg : len);
-	    }
-	    if (end > olen) {
-		rb_ary_store(result, prevlen + len - 1, Qnil);
-	    }
-	}
-	return result;
+            const long end = beg + len;
+            const long prevlen = RARRAY_LEN(result);
+            if (beg < olen) {
+                rb_ary_cat(result, src + beg, end > olen ? olen-beg : len);
+            }
+            if (end > olen) {
+                rb_ary_store(result, prevlen + len - 1, Qnil);
+            }
+        }
+        return result;
     }
     else {
-	beg = NUM2LONG(idx);
+        beg = NUM2LONG(idx);
     }
     return rb_ary_push(result, rb_ary_entry(ary, beg));
 }
@@ -3732,32 +3932,39 @@ append_values_at_single(VALUE result, VALUE ary, long olen, VALUE idx)
  *  of +self+ at the given \Integer or \Range +indexes+.
  *
  *  For each positive +index+, returns the element at offset +index+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.values_at(0, 2) # => [:foo, 2]
  *    a.values_at(0..1) # => [:foo, "bar"]
  *
  *  The given +indexes+ may be in any order, and may repeat:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.values_at(2, 0, 1, 0, 2) # => [2, :foo, "bar", :foo, 2]
  *    a.values_at(1, 0..2) # => ["bar", :foo, "bar", 2]
  *
  *  Assigns +nil+ for an +index+ that is too large:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.values_at(0, 3, 1, 3) # => [:foo, nil, "bar", nil]
  *
  *  Returns a new empty \Array if no arguments given.
  *
  *  For each negative +index+, counts backward from the end of the array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.values_at(-1, -3) # => [2, :foo]
  *
  *  Assigns +nil+ for an +index+ that is too small:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.values_at(0, -5, 1, -6, 2) # => [:foo, nil, "bar", nil, 2]
  *
  *  The given +indexes+ may have a mixture of signs:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.values_at(0, -2, 1, -1) # => [:foo, "bar", "bar", 2]
+ *
  */
 
 static VALUE
@@ -3766,7 +3973,7 @@ rb_ary_values_at(int argc, VALUE *argv, VALUE ary)
     long i, olen = RARRAY_LEN(ary);
     VALUE result = rb_ary_new_capa(argc);
     for (i = 0; i < argc; ++i) {
-	append_values_at_single(result, ary, olen, argv[i]);
+        append_values_at_single(result, ary, olen, argv[i]);
     }
     RB_GC_GUARD(ary);
     return result;
@@ -3781,11 +3988,13 @@ rb_ary_values_at(int argc, VALUE *argv, VALUE ary)
  *  Calls the block, if given, with each element of +self+;
  *  returns a new \Array containing those elements of +self+
  *  for which the block returns a truthy value:
+ *
  *    a = [:foo, 'bar', 2, :bam]
  *    a1 = a.select {|element| element.to_s.start_with?('b') }
  *    a1 # => ["bar", :bam]
  *
  *  Returns a new \Enumerator if no block given:
+ *
  *    a = [:foo, 'bar', 2, :bam]
  *    a.select # => #<Enumerator: [:foo, "bar", 2, :bam]:select>
  *
@@ -3801,9 +4010,9 @@ rb_ary_select(VALUE ary)
     RETURN_SIZED_ENUMERATOR(ary, 0, 0, ary_enum_length);
     result = rb_ary_new2(RARRAY_LEN(ary));
     for (i = 0; i < RARRAY_LEN(ary); i++) {
-	if (RTEST(rb_yield(RARRAY_AREF(ary, i)))) {
-	    rb_ary_push(result, rb_ary_elt(ary, i));
-	}
+        if (RTEST(rb_yield(RARRAY_AREF(ary, i)))) {
+            rb_ary_push(result, rb_ary_elt(ary, i));
+        }
     }
     return result;
 }
@@ -3821,12 +4030,12 @@ select_bang_i(VALUE a)
     long i1, i2;
 
     for (i1 = i2 = 0; i1 < RARRAY_LEN(ary); arg->len[0] = ++i1) {
-	VALUE v = RARRAY_AREF(ary, i1);
-	if (!RTEST(rb_yield(v))) continue;
-	if (i1 != i2) {
-	    rb_ary_store(ary, i2, v);
-	}
-	arg->len[1] = ++i2;
+        VALUE v = RARRAY_AREF(ary, i1);
+        if (!RTEST(rb_yield(v))) continue;
+        if (i1 != i2) {
+            rb_ary_store(ary, i2, v);
+        }
+        arg->len[1] = ++i2;
     }
     return (i1 == i2) ? Qnil : ary;
 }
@@ -3840,15 +4049,15 @@ select_bang_ensure(VALUE a)
     long i1 = arg->len[0], i2 = arg->len[1];
 
     if (i2 < len && i2 < i1) {
-	long tail = 0;
+        long tail = 0;
         rb_ary_modify(ary);
-	if (i1 < len) {
-	    tail = len - i1;
+        if (i1 < len) {
+            tail = len - i1;
             RARRAY_PTR_USE_TRANSIENT(ary, ptr, {
-		    MEMMOVE(ptr + i2, ptr + i1, VALUE, tail);
-		});
-	}
-	ARY_SET_LEN(ary, i2 + tail);
+                    MEMMOVE(ptr + i2, ptr + i1, VALUE, tail);
+                });
+        }
+        ARY_SET_LEN(ary, i2 + tail);
     }
     return ary;
 }
@@ -3862,12 +4071,14 @@ select_bang_ensure(VALUE a)
  *  removes from +self+ those elements for which the block returns +false+ or +nil+.
  *
  *  Returns +self+ if any elements were removed:
+ *
  *    a = [:foo, 'bar', 2, :bam]
  *    a.select! {|element| element.to_s.start_with?('b') } # => ["bar", :bam]
  *
  *  Returns +nil+ if no elements were removed.
  *
  *  Returns a new \Enumerator if no block given:
+ *
  *    a = [:foo, 'bar', 2, :bam]
  *    a.select! # => #<Enumerator: [:foo, "bar", 2, :bam]:select!>
  *
@@ -3894,12 +4105,15 @@ rb_ary_select_bang(VALUE ary)
  *
  *  Retains those elements for which the block returns a truthy value;
  *  deletes all other elements; returns +self+:
+ *
  *    a = [:foo, 'bar', 2, :bam]
  *    a.keep_if {|element| element.to_s.start_with?('b') } # => ["bar", :bam]
  *
  *  Returns a new \Enumerator if no block given:
+ *
  *    a = [:foo, 'bar', 2, :bam]
  *    a.keep_if # => #<Enumerator: [:foo, "bar", 2, :bam]:keep_if>
+ *
  */
 
 static VALUE
@@ -3915,11 +4129,11 @@ ary_resize_smaller(VALUE ary, long len)
 {
     rb_ary_modify(ary);
     if (RARRAY_LEN(ary) > len) {
-	ARY_SET_LEN(ary, len);
-	if (len * 2 < ARY_CAPA(ary) &&
-	    ARY_CAPA(ary) > ARY_DEFAULT_SIZE) {
-	    ary_resize_capa(ary, len * 2);
-	}
+        ARY_SET_LEN(ary, len);
+        if (len * 2 < ARY_CAPA(ary) &&
+            ARY_CAPA(ary) > ARY_DEFAULT_SIZE) {
+            ary_resize_capa(ary, len * 2);
+        }
     }
 }
 
@@ -3933,6 +4147,7 @@ ary_resize_smaller(VALUE ary, long len)
  *  When no block is given,
  *  removes from +self+ each element +ele+ such that <tt>ele == obj</tt>;
  *  returns the last deleted element:
+ *
  *    s1 = 'bar'; s2 = 'bar'
  *    a = [:foo, s1, 2, s2]
  *    a.delete('bar') # => "bar"
@@ -3945,14 +4160,17 @@ ary_resize_smaller(VALUE ary, long len)
  *
  *  If any such elements are found, ignores the block
  *  and returns the last deleted element:
+ *
  *    s1 = 'bar'; s2 = 'bar'
  *    a = [:foo, s1, 2, s2]
  *    deleted_obj = a.delete('bar') {|obj| fail 'Cannot happen' }
  *    a # => [:foo, 2]
  *
  *  If no such elements are found, returns the block's return value:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.delete(:nosuch) {|obj| "#{obj} not found" } # => "nosuch not found"
+ *
  */
 
 VALUE
@@ -3962,22 +4180,22 @@ rb_ary_delete(VALUE ary, VALUE item)
     long i1, i2;
 
     for (i1 = i2 = 0; i1 < RARRAY_LEN(ary); i1++) {
-	VALUE e = RARRAY_AREF(ary, i1);
+        VALUE e = RARRAY_AREF(ary, i1);
 
-	if (rb_equal(e, item)) {
-	    v = e;
-	    continue;
-	}
-	if (i1 != i2) {
-	    rb_ary_store(ary, i2, e);
-	}
-	i2++;
+        if (rb_equal(e, item)) {
+            v = e;
+            continue;
+        }
+        if (i1 != i2) {
+            rb_ary_store(ary, i2, e);
+        }
+        i2++;
     }
     if (RARRAY_LEN(ary) == i2) {
-	if (rb_block_given_p()) {
-	    return rb_yield(item);
-	}
-	return Qnil;
+        if (rb_block_given_p()) {
+            return rb_yield(item);
+        }
+        return Qnil;
     }
 
     ary_resize_smaller(ary, i2);
@@ -3992,18 +4210,18 @@ rb_ary_delete_same(VALUE ary, VALUE item)
     long i1, i2;
 
     for (i1 = i2 = 0; i1 < RARRAY_LEN(ary); i1++) {
-	VALUE e = RARRAY_AREF(ary, i1);
+        VALUE e = RARRAY_AREF(ary, i1);
 
-	if (e == item) {
-	    continue;
-	}
-	if (i1 != i2) {
-	    rb_ary_store(ary, i2, e);
-	}
-	i2++;
+        if (e == item) {
+            continue;
+        }
+        if (i1 != i2) {
+            rb_ary_store(ary, i2, e);
+        }
+        i2++;
     }
     if (RARRAY_LEN(ary) == i2) {
-	return;
+        return;
     }
 
     ary_resize_smaller(ary, i2);
@@ -4017,8 +4235,8 @@ rb_ary_delete_at(VALUE ary, long pos)
 
     if (pos >= len) return Qnil;
     if (pos < 0) {
-	pos += len;
-	if (pos < 0) return Qnil;
+        pos += len;
+        if (pos < 0) return Qnil;
     }
 
     rb_ary_modify(ary);
@@ -4038,6 +4256,7 @@ rb_ary_delete_at(VALUE ary, long pos)
  *  Deletes an element from +self+, per the given \Integer +index+.
  *
  *  When +index+ is non-negative, deletes the element at offset +index+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.delete_at(1) # => "bar"
  *    a # => [:foo, 2]
@@ -4045,6 +4264,7 @@ rb_ary_delete_at(VALUE ary, long pos)
  *  If index is too large, returns +nil+.
  *
  *  When +index+ is negative, counts backward from the end of the array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.delete_at(-2) # => "bar"
  *    a # => [:foo, 2]
@@ -4098,11 +4318,13 @@ ary_slice_bang_by_rb_ary_splice(VALUE ary, long pos, long len)
  *
  *  When the only argument is an \Integer +n+,
  *  removes and returns the _nth_ element in +self+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.slice!(1) # => "bar"
  *    a # => [:foo, 2]
  *
  *  If +n+ is negative, counts backwards from the end of +self+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.slice!(-1) # => 2
  *    a # => [:foo, "bar"]
@@ -4112,12 +4334,14 @@ ary_slice_bang_by_rb_ary_splice(VALUE ary, long pos, long len)
  *  When the only arguments are Integers +start+ and +length+,
  *  removes +length+ elements from +self+ beginning at offset  +start+;
  *  returns the deleted objects in a new \Array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.slice!(0, 2) # => [:foo, "bar"]
  *    a # => [2]
  *
  *  If <tt>start + length</tt> exceeds the array size,
  *  removes and returns all elements from offset +start+ to the end:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.slice!(1, 50) # => ["bar", 2]
  *    a # => [:foo]
@@ -4129,8 +4353,9 @@ ary_slice_bang_by_rb_ary_splice(VALUE ary, long pos, long len)
  *
  *  When the only argument is a \Range object +range+,
  *  treats <tt>range.min</tt> as +start+ above and <tt>range.size</tt> as +length+ above:
+ *
  *    a = [:foo, 'bar', 2]
- *     a.slice!(1..2) # => ["bar", 2]
+ *    a.slice!(1..2) # => ["bar", 2]
  *    a # => [:foo]
  *
  *  If <tt>range.start == a.size</tt>, returns a new empty \Array.
@@ -4138,15 +4363,18 @@ ary_slice_bang_by_rb_ary_splice(VALUE ary, long pos, long len)
  *  If <tt>range.start</tt> is larger than the array size, returns +nil+.
  *
  *  If <tt>range.end</tt> is negative, counts backwards from the end of the array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.slice!(0..-2) # => [:foo, "bar"]
  *    a # => [2]
  *
  *  If <tt>range.start</tt> is negative,
  *  calculates the start index backwards from the end of the array:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.slice!(-2..2) # => ["bar", 2]
  *    a # => [:foo]
+ *
  */
 
 static VALUE
@@ -4160,23 +4388,23 @@ rb_ary_slice_bang(int argc, VALUE *argv, VALUE ary)
     arg1 = argv[0];
 
     if (argc == 2) {
-	pos = NUM2LONG(argv[0]);
-	len = NUM2LONG(argv[1]);
+        pos = NUM2LONG(argv[0]);
+        len = NUM2LONG(argv[1]);
         return ary_slice_bang_by_rb_ary_splice(ary, pos, len);
     }
 
     if (!FIXNUM_P(arg1)) {
-	switch (rb_range_beg_len(arg1, &pos, &len, RARRAY_LEN(ary), 0)) {
-	  case Qtrue:
-	    /* valid range */
+        switch (rb_range_beg_len(arg1, &pos, &len, RARRAY_LEN(ary), 0)) {
+          case Qtrue:
+            /* valid range */
             return ary_slice_bang_by_rb_ary_splice(ary, pos, len);
-	  case Qnil:
-	    /* invalid range */
-	    return Qnil;
-	  default:
-	    /* not a range */
-	    break;
-	}
+          case Qnil:
+            /* invalid range */
+            return Qnil;
+          default:
+            /* not a range */
+            break;
+        }
     }
 
     return rb_ary_delete_at(ary, NUM2LONG(arg1));
@@ -4188,11 +4416,11 @@ ary_reject(VALUE orig, VALUE result)
     long i;
 
     for (i = 0; i < RARRAY_LEN(orig); i++) {
-	VALUE v = RARRAY_AREF(orig, i);
+        VALUE v = RARRAY_AREF(orig, i);
 
         if (!RTEST(rb_yield(v))) {
-	    rb_ary_push(result, v);
-	}
+            rb_ary_push(result, v);
+        }
     }
     return result;
 }
@@ -4205,12 +4433,12 @@ reject_bang_i(VALUE a)
     long i1, i2;
 
     for (i1 = i2 = 0; i1 < RARRAY_LEN(ary); arg->len[0] = ++i1) {
-	VALUE v = RARRAY_AREF(ary, i1);
-	if (RTEST(rb_yield(v))) continue;
-	if (i1 != i2) {
-	    rb_ary_store(ary, i2, v);
-	}
-	arg->len[1] = ++i2;
+        VALUE v = RARRAY_AREF(ary, i1);
+        if (RTEST(rb_yield(v))) continue;
+        if (i1 != i2) {
+            rb_ary_store(ary, i2, v);
+        }
+        arg->len[1] = ++i2;
     }
     return (i1 == i2) ? Qnil : ary;
 }
@@ -4233,14 +4461,17 @@ ary_reject_bang(VALUE ary)
  *  Removes each element for which the block returns a truthy value.
  *
  *  Returns +self+ if any elements removed:
+ *
  *    a = [:foo, 'bar', 2, 'bat']
  *    a.reject! {|element| element.to_s.start_with?('b') } # => [:foo, 2]
  *
  *  Returns +nil+ if no elements removed.
  *
  *  Returns a new \Enumerator if no block given:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.reject! # => #<Enumerator: [:foo, "bar", 2]:reject!>
+ *
  */
 
 static VALUE
@@ -4258,13 +4489,16 @@ rb_ary_reject_bang(VALUE ary)
  *
  *  Returns a new \Array whose elements are all those from +self+
  *  for which the block returns +false+ or +nil+:
+ *
  *    a = [:foo, 'bar', 2, 'bat']
  *    a1 = a.reject {|element| element.to_s.start_with?('b') }
  *    a1 # => [:foo, 2]
  *
  *  Returns a new \Enumerator if no block given:
+ *
  *     a = [:foo, 'bar', 2]
  *     a.reject # => #<Enumerator: [:foo, "bar", 2]:reject>
+ *
  */
 
 static VALUE
@@ -4285,13 +4519,16 @@ rb_ary_reject(VALUE ary)
  *
  *  Removes each element in +self+ for which the block returns a truthy value;
  *  returns +self+:
+ *
  *    a = [:foo, 'bar', 2, 'bat']
  *    a.delete_if {|element| element.to_s.start_with?('b') } # => [:foo, 2]
  *
  *  Returns a new \Enumerator if no block given:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.delete_if # => #<Enumerator: [:foo, "bar", 2]:delete_if>
- */
+ *
+3 */
 
 static VALUE
 rb_ary_delete_if(VALUE ary)
@@ -4322,9 +4559,9 @@ take_items(VALUE obj, long n)
     if (!NIL_P(result)) return rb_ary_subseq(result, 0, n);
     result = rb_ary_new2(n);
     args[0] = result; args[1] = (VALUE)n;
-    if (rb_check_block_call(obj, idEach, 0, 0, take_i, (VALUE)args) == Qundef)
-	rb_raise(rb_eTypeError, "wrong argument type %"PRIsVALUE" (must respond to :each)",
-		 rb_obj_class(obj));
+    if (UNDEF_P(rb_check_block_call(obj, idEach, 0, 0, take_i, (VALUE)args)))
+        rb_raise(rb_eTypeError, "wrong argument type %"PRIsVALUE" (must respond to :each)",
+                 rb_obj_class(obj));
     return result;
 }
 
@@ -4339,10 +4576,12 @@ take_items(VALUE obj, long n)
  *
  *  Each nested array <tt>new_array[n]</tt> is of size <tt>other_arrays.size+1</tt>,
  *  and contains:
+ *
  *  - The _nth_ element of +self+.
  *  - The _nth_ element of each of the +other_arrays+.
  *
  *  If all +other_arrays+ and +self+ are the same size:
+ *
  *    a = [:a0, :a1, :a2, :a3]
  *    b = [:b0, :b1, :b2, :b3]
  *    c = [:c0, :c1, :c2, :c3]
@@ -4351,6 +4590,7 @@ take_items(VALUE obj, long n)
  *
  *  If any array in +other_arrays+ is smaller than +self+,
  *  fills to <tt>self.size</tt> with +nil+:
+ *
  *    a = [:a0, :a1, :a2, :a3]
  *    b = [:b0, :b1, :b2]
  *    c = [:c0, :c1]
@@ -4359,23 +4599,27 @@ take_items(VALUE obj, long n)
  *
  *  If any array in +other_arrays+ is larger than +self+,
  *  its trailing elements are ignored:
+ *
  *    a = [:a0, :a1, :a2, :a3]
  *    b = [:b0, :b1, :b2, :b3, :b4]
  *    c = [:c0, :c1, :c2, :c3, :c4, :c5]
  *    d = a.zip(b, c)
  *    d # => [[:a0, :b0, :c0], [:a1, :b1, :c1], [:a2, :b2, :c2], [:a3, :b3, :c3]]
  *
- *  When a block is given, calls the block with each of the sub-arrays (formed as above); returns nil
+ *  When a block is given, calls the block with each of the sub-arrays (formed as above); returns +nil+:
+ *
  *    a = [:a0, :a1, :a2, :a3]
  *    b = [:b0, :b1, :b2, :b3]
  *    c = [:c0, :c1, :c2, :c3]
  *    a.zip(b, c) {|sub_array| p sub_array} # => nil
  *
  *  Output:
+ *
  *    [:a0, :b0, :c0]
  *    [:a1, :b1, :c1]
  *    [:a2, :b2, :c2]
  *    [:a3, :b3, :c3]
+ *
  */
 
 static VALUE
@@ -4386,51 +4630,51 @@ rb_ary_zip(int argc, VALUE *argv, VALUE ary)
     VALUE result = Qnil;
 
     for (i=0; i<argc; i++) {
-	argv[i] = take_items(argv[i], len);
+        argv[i] = take_items(argv[i], len);
     }
 
     if (rb_block_given_p()) {
-	int arity = rb_block_arity();
-
-	if (arity > 1) {
-	    VALUE work, *tmp;
-
-	    tmp = ALLOCV_N(VALUE, work, argc+1);
-
-	    for (i=0; i<RARRAY_LEN(ary); i++) {
-		tmp[0] = RARRAY_AREF(ary, i);
-		for (j=0; j<argc; j++) {
-		    tmp[j+1] = rb_ary_elt(argv[j], i);
-		}
-		rb_yield_values2(argc+1, tmp);
-	    }
-
-	    if (work) ALLOCV_END(work);
-	}
-	else {
-	    for (i=0; i<RARRAY_LEN(ary); i++) {
-		VALUE tmp = rb_ary_new2(argc+1);
-
-		rb_ary_push(tmp, RARRAY_AREF(ary, i));
-		for (j=0; j<argc; j++) {
-		    rb_ary_push(tmp, rb_ary_elt(argv[j], i));
-		}
-		rb_yield(tmp);
-	    }
-	}
+        int arity = rb_block_arity();
+
+        if (arity > 1) {
+            VALUE work, *tmp;
+
+            tmp = ALLOCV_N(VALUE, work, argc+1);
+
+            for (i=0; i<RARRAY_LEN(ary); i++) {
+                tmp[0] = RARRAY_AREF(ary, i);
+                for (j=0; j<argc; j++) {
+                    tmp[j+1] = rb_ary_elt(argv[j], i);
+                }
+                rb_yield_values2(argc+1, tmp);
+            }
+
+            if (work) ALLOCV_END(work);
+        }
+        else {
+            for (i=0; i<RARRAY_LEN(ary); i++) {
+                VALUE tmp = rb_ary_new2(argc+1);
+
+                rb_ary_push(tmp, RARRAY_AREF(ary, i));
+                for (j=0; j<argc; j++) {
+                    rb_ary_push(tmp, rb_ary_elt(argv[j], i));
+                }
+                rb_yield(tmp);
+            }
+        }
     }
     else {
-	result = rb_ary_new_capa(len);
+        result = rb_ary_new_capa(len);
 
-	for (i=0; i<len; i++) {
-	    VALUE tmp = rb_ary_new_capa(argc+1);
+        for (i=0; i<len; i++) {
+            VALUE tmp = rb_ary_new_capa(argc+1);
 
-	    rb_ary_push(tmp, RARRAY_AREF(ary, i));
-	    for (j=0; j<argc; j++) {
-		rb_ary_push(tmp, rb_ary_elt(argv[j], i));
-	    }
-	    rb_ary_push(result, tmp);
-	}
+            rb_ary_push(tmp, RARRAY_AREF(ary, i));
+            for (j=0; j<argc; j++) {
+                rb_ary_push(tmp, rb_ary_elt(argv[j], i));
+            }
+            rb_ary_push(result, tmp);
+        }
     }
 
     return result;
@@ -4442,8 +4686,10 @@ rb_ary_zip(int argc, VALUE *argv, VALUE ary)
  *
  *  Transposes the rows and columns in an \Array of Arrays;
  *  the nested Arrays must all be the same size:
+ *
  *    a = [[:a0, :a1], [:b0, :b1], [:c0, :c1]]
  *    a.transpose # => [[:a0, :b0, :c0], [:a1, :b1, :c1]]
+ *
  */
 
 static VALUE
@@ -4455,21 +4701,21 @@ rb_ary_transpose(VALUE ary)
     alen = RARRAY_LEN(ary);
     if (alen == 0) return rb_ary_dup(ary);
     for (i=0; i<alen; i++) {
-	tmp = to_ary(rb_ary_elt(ary, i));
-	if (elen < 0) {		/* first element */
-	    elen = RARRAY_LEN(tmp);
-	    result = rb_ary_new2(elen);
-	    for (j=0; j<elen; j++) {
-		rb_ary_store(result, j, rb_ary_new2(alen));
-	    }
-	}
-	else if (elen != RARRAY_LEN(tmp)) {
-	    rb_raise(rb_eIndexError, "element size differs (%ld should be %ld)",
-		     RARRAY_LEN(tmp), elen);
-	}
-	for (j=0; j<elen; j++) {
-	    rb_ary_store(rb_ary_elt(result, j), i, rb_ary_elt(tmp, j));
-	}
+        tmp = to_ary(rb_ary_elt(ary, i));
+        if (elen < 0) {		/* first element */
+            elen = RARRAY_LEN(tmp);
+            result = rb_ary_new2(elen);
+            for (j=0; j<elen; j++) {
+                rb_ary_store(result, j, rb_ary_new2(alen));
+            }
+        }
+        else if (elen != RARRAY_LEN(tmp)) {
+            rb_raise(rb_eIndexError, "element size differs (%ld should be %ld)",
+                     RARRAY_LEN(tmp), elen);
+        }
+        for (j=0; j<elen; j++) {
+            rb_ary_store(rb_ary_elt(result, j), i, rb_ary_elt(tmp, j));
+        }
     }
     return result;
 }
@@ -4479,8 +4725,10 @@ rb_ary_transpose(VALUE ary)
  *    array.replace(other_array) -> self
  *
  *  Replaces the content of +self+ with the content of +other_array+; returns +self+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.replace(['foo', :bar, 3]) # => ["foo", :bar, 3]
+ *
  */
 
 VALUE
@@ -4503,14 +4751,16 @@ rb_ary_replace(VALUE copy, VALUE orig)
      * contents of orig. */
     else if (ARY_EMBED_P(orig)) {
         long len = ARY_EMBED_LEN(orig);
-
         VALUE *ptr = ary_heap_alloc(copy, len);
-        MEMCPY(ptr, ARY_EMBED_PTR(orig), VALUE, len);
 
         FL_UNSET_EMBED(copy);
         ARY_SET_PTR(copy, ptr);
         ARY_SET_LEN(copy, len);
         ARY_SET_CAPA(copy, len);
+
+        // No allocation and exception expected that could leave `copy` in a
+        // bad state from the edits above.
+        ary_memcpy(copy, 0, len, RARRAY_CONST_PTR_TRANSIENT(orig));
     }
 #endif
     /* Otherwise, orig is on heap and copy does not have enough space to embed
@@ -4531,8 +4781,10 @@ rb_ary_replace(VALUE copy, VALUE orig)
  *     array.clear -> self
  *
  *  Removes all elements from +self+:
+ *
  *    a = [:foo, 'bar', 2]
  *    a.clear # => []
+ *
  */
 
 VALUE
@@ -4540,11 +4792,11 @@ rb_ary_clear(VALUE ary)
 {
     rb_ary_modify_check(ary);
     if (ARY_SHARED_P(ary)) {
-	if (!ARY_EMBED_P(ary)) {
-	    rb_ary_unshare(ary);
-	    FL_SET_EMBED(ary);
+        if (!ARY_EMBED_P(ary)) {
+            rb_ary_unshare(ary);
+            FL_SET_EMBED(ary);
             ARY_SET_EMBED_LEN(ary, 0);
-	}
+        }
     }
     else {
         ARY_SET_LEN(ary, 0);
@@ -4570,6 +4822,7 @@ rb_ary_clear(VALUE ary)
  *  Replaces specified elements in +self+ with specified objects; returns +self+.
  *
  *  With argument +obj+ and no block given, replaces all elements with that one object:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a # => ["a", "b", "c", "d"]
  *    a.fill(:X) # => [:X, :X, :X, :X]
@@ -4579,20 +4832,24 @@ rb_ary_clear(VALUE ary)
  *
  *  If +start+ is in range (<tt>0 <= start < array.size</tt>),
  *  replaces all elements from offset +start+ through the end:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(:X, 2) # => ["a", "b", :X, :X]
  *
  *  If +start+ is too large (<tt>start >= array.size</tt>), does nothing:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(:X, 4) # => ["a", "b", "c", "d"]
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(:X, 5) # => ["a", "b", "c", "d"]
  *
  *  If +start+ is negative, counts from the end (starting index is <tt>start + array.size</tt>):
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(:X, -2) # => ["a", "b", :X, :X]
  *
  *  If +start+ is too small (less than and far from zero), replaces all elements:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(:X, -6) # => [:X, :X, :X, :X]
  *    a = ['a', 'b', 'c', 'd']
@@ -4602,20 +4859,24 @@ rb_ary_clear(VALUE ary)
  *  replaces elements based on the given +start+ and +length+.
  *
  *  If +start+ is in range, replaces +length+ elements beginning at offset +start+:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(:X, 1, 1) # => ["a", :X, "c", "d"]
  *
  *  If +start+ is negative, counts from the end:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(:X, -2, 1) # => ["a", "b", :X, "d"]
  *
  *  If +start+ is large (<tt>start >= array.size</tt>), extends +self+ with +nil+:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(:X, 5, 0) # => ["a", "b", "c", "d", nil]
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(:X, 5, 2) # => ["a", "b", "c", "d", nil, :X, :X]
  *
  *  If +length+ is zero or negative, replaces no elements:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(:X, 1, 0) # => ["a", "b", "c", "d"]
  *    a.fill(:X, 1, -1) # => ["a", "b", "c", "d"]
@@ -4625,14 +4886,17 @@ rb_ary_clear(VALUE ary)
  *
  *  If the range is positive and ascending (<tt>0 < range.begin <= range.end</tt>),
  *  replaces elements from <tt>range.begin</tt> to <tt>range.end</tt>:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(:X, (1..1)) # => ["a", :X, "c", "d"]
  *
  *  If <tt>range.first</tt> is negative, replaces no elements:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(:X, (-1..1)) # => ["a", "b", "c", "d"]
  *
  *  If <tt>range.last</tt> is negative, counts from the end:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(:X, (0..-2)) # => [:X, :X, :X, "d"]
  *    a = ['a', 'b', 'c', 'd']
@@ -4640,6 +4904,7 @@ rb_ary_clear(VALUE ary)
  *
  *  If <tt>range.last</tt> and <tt>range.last</tt> are both negative,
  *  both count from the end of the array:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(:X, (-1..-1)) # => ["a", "b", "c", :X]
  *    a = ['a', 'b', 'c', 'd']
@@ -4647,29 +4912,34 @@ rb_ary_clear(VALUE ary)
  *
  *  With no arguments and a block given, calls the block with each index;
  *  replaces the corresponding element with the block's return value:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill { |index| "new_#{index}" } # => ["new_0", "new_1", "new_2", "new_3"]
  *
  *  With argument +start+ and a block given, calls the block with each index
  *  from offset +start+ to the end; replaces the corresponding element
- *  with the block's return value:
+ *  with the block's return value.
  *
  *  If start is in range (<tt>0 <= start < array.size</tt>),
  *  replaces from offset +start+ to the end:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(1) { |index| "new_#{index}" } # => ["a", "new_1", "new_2", "new_3"]
  *
  *  If +start+ is too large(<tt>start >= array.size</tt>), does nothing:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(4) { |index| fail 'Cannot happen' } # => ["a", "b", "c", "d"]
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(4) { |index| fail 'Cannot happen' } # => ["a", "b", "c", "d"]
  *
  *  If +start+ is negative, counts from the end:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(-2) { |index| "new_#{index}" } # => ["a", "b", "new_2", "new_3"]
  *
  *  If start is too small (<tt>start <= -array.size</tt>, replaces all elements:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(-6) { |index| "new_#{index}" } # => ["new_0", "new_1", "new_2", "new_3"]
  *    a = ['a', 'b', 'c', 'd']
@@ -4680,20 +4950,24 @@ rb_ary_clear(VALUE ary)
  *  replaces the corresponding element with the block's return value.
  *
  *  If +start+ is in range, replaces +length+ elements beginning at offset +start+:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(1, 1) { |index| "new_#{index}" } # => ["a", "new_1", "c", "d"]
  *
  *  If start is negative, counts from the end:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(-2, 1) { |index| "new_#{index}" } # => ["a", "b", "new_2", "d"]
  *
  *  If +start+ is large (<tt>start >= array.size</tt>), extends +self+ with +nil+:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(5, 0) { |index| "new_#{index}" } # => ["a", "b", "c", "d", nil]
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(5, 2) { |index| "new_#{index}" } # => ["a", "b", "c", "d", nil, "new_5", "new_6"]
  *
  *  If +length+ is zero or less, replaces no elements:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(1, 0) { |index| "new_#{index}" } # => ["a", "b", "c", "d"]
  *    a.fill(1, -1) { |index| "new_#{index}" } # => ["a", "b", "c", "d"]
@@ -4704,14 +4978,17 @@ rb_ary_clear(VALUE ary)
  *
  *  If the range is positive and ascending (<tt>range 0 < range.begin <= range.end</tt>,
  *  replaces elements from <tt>range.begin</tt> to <tt>range.end</tt>:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(1..1) { |index| "new_#{index}" } # => ["a", "new_1", "c", "d"]
  *
  *  If +range.first+ is negative, does nothing:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(-1..1) { |index| fail 'Cannot happen' } # => ["a", "b", "c", "d"]
  *
  *  If <tt>range.last</tt> is negative, counts from the end:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(0..-2) { |index| "new_#{index}" } # => ["new_0", "new_1", "new_2", "d"]
  *    a = ['a', 'b', 'c', 'd']
@@ -4719,10 +4996,12 @@ rb_ary_clear(VALUE ary)
  *
  *  If <tt>range.first</tt> and <tt>range.last</tt> are both negative,
  *  both count from the end:
+ *
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(-1..-1) { |index| "new_#{index}" } # => ["a", "b", "c", "new_3"]
  *    a = ['a', 'b', 'c', 'd']
  *    a.fill(-2..-2) { |index| "new_#{index}" } # => ["a", "b", "new_2", "d"]
+ *
  */
 
 static VALUE
@@ -4732,59 +5011,59 @@ rb_ary_fill(int argc, VALUE *argv, VALUE ary)
     long beg = 0, end = 0, len = 0;
 
     if (rb_block_given_p()) {
-	rb_scan_args(argc, argv, "02", &arg1, &arg2);
-	argc += 1;		/* hackish */
+        rb_scan_args(argc, argv, "02", &arg1, &arg2);
+        argc += 1;		/* hackish */
     }
     else {
-	rb_scan_args(argc, argv, "12", &item, &arg1, &arg2);
+        rb_scan_args(argc, argv, "12", &item, &arg1, &arg2);
     }
     switch (argc) {
       case 1:
-	beg = 0;
-	len = RARRAY_LEN(ary);
-	break;
+        beg = 0;
+        len = RARRAY_LEN(ary);
+        break;
       case 2:
-	if (rb_range_beg_len(arg1, &beg, &len, RARRAY_LEN(ary), 1)) {
-	    break;
-	}
-	/* fall through */
+        if (rb_range_beg_len(arg1, &beg, &len, RARRAY_LEN(ary), 1)) {
+            break;
+        }
+        /* fall through */
       case 3:
-	beg = NIL_P(arg1) ? 0 : NUM2LONG(arg1);
-	if (beg < 0) {
-	    beg = RARRAY_LEN(ary) + beg;
-	    if (beg < 0) beg = 0;
-	}
-	len = NIL_P(arg2) ? RARRAY_LEN(ary) - beg : NUM2LONG(arg2);
-	break;
+        beg = NIL_P(arg1) ? 0 : NUM2LONG(arg1);
+        if (beg < 0) {
+            beg = RARRAY_LEN(ary) + beg;
+            if (beg < 0) beg = 0;
+        }
+        len = NIL_P(arg2) ? RARRAY_LEN(ary) - beg : NUM2LONG(arg2);
+        break;
     }
     rb_ary_modify(ary);
     if (len < 0) {
         return ary;
     }
     if (beg >= ARY_MAX_SIZE || len > ARY_MAX_SIZE - beg) {
-	rb_raise(rb_eArgError, "argument too big");
+        rb_raise(rb_eArgError, "argument too big");
     }
     end = beg + len;
     if (RARRAY_LEN(ary) < end) {
-	if (end >= ARY_CAPA(ary)) {
-	    ary_resize_capa(ary, end);
-	}
-	ary_mem_clear(ary, RARRAY_LEN(ary), end - RARRAY_LEN(ary));
-	ARY_SET_LEN(ary, end);
+        if (end >= ARY_CAPA(ary)) {
+            ary_resize_capa(ary, end);
+        }
+        ary_mem_clear(ary, RARRAY_LEN(ary), end - RARRAY_LEN(ary));
+        ARY_SET_LEN(ary, end);
     }
 
-    if (item == Qundef) {
-	VALUE v;
-	long i;
+    if (UNDEF_P(item)) {
+        VALUE v;
+        long i;
 
-	for (i=beg; i<end; i++) {
-	    v = rb_yield(LONG2NUM(i));
-	    if (i>=RARRAY_LEN(ary)) break;
-	    ARY_SET(ary, i, v);
-	}
+        for (i=beg; i<end; i++) {
+            v = rb_yield(LONG2NUM(i));
+            if (i>=RARRAY_LEN(ary)) break;
+            ARY_SET(ary, i, v);
+        }
     }
     else {
-	ary_memfill(ary, beg, len, item);
+        ary_memfill(ary, beg, len, item);
     }
     return ary;
 }
@@ -4795,6 +5074,7 @@ rb_ary_fill(int argc, VALUE *argv, VALUE ary)
  *
  *  Returns a new \Array containing all elements of +array+
  *  followed by all elements of +other_array+:
+ *
  *    a = [0, 1] + [2, 3]
  *    a # => [0, 1, 2, 3]
  *
@@ -4835,6 +5115,7 @@ ary_append(VALUE x, VALUE y)
  *    array.concat(*other_arrays) -> self
  *
  *  Adds to +array+ all elements from each \Array in +other_arrays+; returns +self+:
+ *
  *    a = [0, 1]
  *    a.concat([2, 3], [4, 5]) # => [0, 1, 2, 3, 4, 5]
  */
@@ -4845,15 +5126,15 @@ rb_ary_concat_multi(int argc, VALUE *argv, VALUE ary)
     rb_ary_modify_check(ary);
 
     if (argc == 1) {
-	rb_ary_concat(ary, argv[0]);
+        rb_ary_concat(ary, argv[0]);
     }
     else if (argc > 1) {
-	int i;
-	VALUE args = rb_ary_tmp_new(argc);
-	for (i = 0; i < argc; i++) {
-	    rb_ary_concat(args, argv[i]);
-	}
-	ary_append(ary, args);
+        int i;
+        VALUE args = rb_ary_hidden_new(argc);
+        for (i = 0; i < argc; i++) {
+            rb_ary_concat(args, argv[i]);
+        }
+        ary_append(ary, args);
     }
 
     ary_verify(ary);
@@ -4873,12 +5154,15 @@ rb_ary_concat(VALUE x, VALUE y)
  *
  *  When non-negative argument \Integer +n+ is given,
  *  returns a new \Array built by concatenating the +n+ copies of +self+:
+ *
  *    a = ['x', 'y']
  *    a * 3 # => ["x", "y", "x", "y", "x", "y"]
  *
  *  When \String argument +string_separator+ is given,
  *  equivalent to <tt>array.join(string_separator)</tt>:
+ *
  *    [0, [0, 1], {foo: 0}] * ', ' # => "0, 0, 1, {:foo=>0}"
+ *
  */
 
 static VALUE
@@ -4890,19 +5174,19 @@ rb_ary_times(VALUE ary, VALUE times)
 
     tmp = rb_check_string_type(times);
     if (!NIL_P(tmp)) {
-	return rb_ary_join(ary, tmp);
+        return rb_ary_join(ary, tmp);
     }
 
     len = NUM2LONG(times);
     if (len == 0) {
         ary2 = ary_new(rb_cArray, 0);
-	goto out;
+        goto out;
     }
     if (len < 0) {
-	rb_raise(rb_eArgError, "negative argument");
+        rb_raise(rb_eArgError, "negative argument");
     }
     if (ARY_MAX_SIZE/len < RARRAY_LEN(ary)) {
-	rb_raise(rb_eArgError, "argument too big");
+        rb_raise(rb_eArgError, "argument too big");
     }
     len *= RARRAY_LEN(ary);
 
@@ -4912,8 +5196,8 @@ rb_ary_times(VALUE ary, VALUE times)
     ptr = RARRAY_CONST_PTR_TRANSIENT(ary);
     t = RARRAY_LEN(ary);
     if (0 < t) {
-	ary_memcpy(ary2, 0, t, ptr);
-	while (t <= len/2) {
+        ary_memcpy(ary2, 0, t, ptr);
+        while (t <= len/2) {
             ary_memcpy(ary2, t, t, RARRAY_CONST_PTR_TRANSIENT(ary2));
             t *= 2;
         }
@@ -4931,6 +5215,7 @@ rb_ary_times(VALUE ary, VALUE times)
  *
  *  Returns the first element in +self+ that is an \Array
  *  whose first element <tt>==</tt> +obj+:
+ *
  *    a = [{foo: 0}, [2, 4], [4, 5, 6], [4, 5]]
  *    a.assoc(4) # => [4, 5, 6]
  *
@@ -4946,10 +5231,10 @@ rb_ary_assoc(VALUE ary, VALUE key)
     VALUE v;
 
     for (i = 0; i < RARRAY_LEN(ary); ++i) {
-	v = rb_check_array_type(RARRAY_AREF(ary, i));
-	if (!NIL_P(v) && RARRAY_LEN(v) > 0 &&
-	    rb_equal(RARRAY_AREF(v, 0), key))
-	    return v;
+        v = rb_check_array_type(RARRAY_AREF(ary, i));
+        if (!NIL_P(v) && RARRAY_LEN(v) > 0 &&
+            rb_equal(RARRAY_AREF(v, 0), key))
+            return v;
     }
     return Qnil;
 }
@@ -4960,6 +5245,7 @@ rb_ary_assoc(VALUE ary, VALUE key)
  *
  *  Returns the first element in +self+ that is an \Array
  *  whose second element <tt>==</tt> +obj+:
+ *
  *    a = [{foo: 0}, [2, 4], [4, 5, 6], [4, 5]]
  *    a.rassoc(4) # => [2, 4]
  *
@@ -4975,11 +5261,11 @@ rb_ary_rassoc(VALUE ary, VALUE value)
     VALUE v;
 
     for (i = 0; i < RARRAY_LEN(ary); ++i) {
-	v = RARRAY_AREF(ary, i);
-	if (RB_TYPE_P(v, T_ARRAY) &&
-	    RARRAY_LEN(v) > 1 &&
-	    rb_equal(RARRAY_AREF(v, 1), value))
-	    return v;
+        v = RARRAY_AREF(ary, i);
+        if (RB_TYPE_P(v, T_ARRAY) &&
+            RARRAY_LEN(v) > 1 &&
+            rb_equal(RARRAY_AREF(v, 1), value))
+            return v;
     }
     return Qnil;
 }
@@ -4998,22 +5284,22 @@ recursive_equal(VALUE ary1, VALUE ary2, int recur)
     len1 = RARRAY_LEN(ary1);
 
     for (i = 0; i < len1; i++) {
-	if (*p1 != *p2) {
-	    if (rb_equal(*p1, *p2)) {
-		len1 = RARRAY_LEN(ary1);
-		if (len1 != RARRAY_LEN(ary2))
-		    return Qfalse;
-		if (len1 < i)
-		    return Qtrue;
+        if (*p1 != *p2) {
+            if (rb_equal(*p1, *p2)) {
+                len1 = RARRAY_LEN(ary1);
+                if (len1 != RARRAY_LEN(ary2))
+                    return Qfalse;
+                if (len1 < i)
+                    return Qtrue;
                 p1 = RARRAY_CONST_PTR(ary1) + i;
                 p2 = RARRAY_CONST_PTR(ary2) + i;
-	    }
-	    else {
-		return Qfalse;
-	    }
-	}
-	p1++;
-	p2++;
+            }
+            else {
+                return Qfalse;
+            }
+        }
+        p1++;
+        p2++;
     }
     return Qtrue;
 }
@@ -5024,6 +5310,7 @@ recursive_equal(VALUE ary1, VALUE ary2, int recur)
  *
  *  Returns +true+ if both <tt>array.size == other_array.size</tt>
  *  and for each index +i+ in +array+, <tt>array[i] == other_array[i]</tt>:
+ *
  *    a0 = [:foo, 'bar', 2]
  *    a1 = [:foo, 'bar', 2.0]
  *    a1 == a0 # => true
@@ -5040,10 +5327,10 @@ rb_ary_equal(VALUE ary1, VALUE ary2)
 {
     if (ary1 == ary2) return Qtrue;
     if (!RB_TYPE_P(ary2, T_ARRAY)) {
-	if (!rb_respond_to(ary2, idTo_ary)) {
-	    return Qfalse;
-	}
-	return rb_equal(ary2, ary1);
+        if (!rb_respond_to(ary2, idTo_ary)) {
+            return Qfalse;
+        }
+        return rb_equal(ary2, ary1);
     }
     if (RARRAY_LEN(ary1) != RARRAY_LEN(ary2)) return Qfalse;
     if (RARRAY_CONST_PTR_TRANSIENT(ary1) == RARRAY_CONST_PTR_TRANSIENT(ary2)) return Qtrue;
@@ -5057,8 +5344,8 @@ recursive_eql(VALUE ary1, VALUE ary2, int recur)
 
     if (recur) return Qtrue; /* Subtle! */
     for (i=0; i<RARRAY_LEN(ary1); i++) {
-	if (!rb_eql(rb_ary_elt(ary1, i), rb_ary_elt(ary2, i)))
-	    return Qfalse;
+        if (!rb_eql(rb_ary_elt(ary1, i), rb_ary_elt(ary2, i)))
+            return Qfalse;
     }
     return Qtrue;
 }
@@ -5069,6 +5356,7 @@ recursive_eql(VALUE ary1, VALUE ary2, int recur)
  *
  *  Returns +true+ if +self+ and +other_array+ are the same size,
  *  and if, for each index +i+ in +self+, <tt>self[i].eql? other_array[i]</tt>:
+ *
  *    a0 = [:foo, 'bar', 2]
  *    a1 = [:foo, 'bar', 2]
  *    a1.eql?(a0) # => true
@@ -5096,8 +5384,10 @@ rb_ary_eql(VALUE ary1, VALUE ary2)
  *  Returns the integer hash value for +self+.
  *
  *  Two arrays with the same content will have the same hash code (and will compare using eql?):
+ *
  *    [0, 1, 2].hash == [0, 1, 2].hash # => true
  *    [0, 1, 2].hash == [0, 1, 3].hash # => false
+ *
  */
 
 static VALUE
@@ -5110,8 +5400,8 @@ rb_ary_hash(VALUE ary)
     h = rb_hash_start(RARRAY_LEN(ary));
     h = rb_hash_uint(h, (st_index_t)rb_ary_hash);
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	n = rb_hash(RARRAY_AREF(ary, i));
-	h = rb_hash_uint(h, NUM2LONG(n));
+        n = rb_hash(RARRAY_AREF(ary, i));
+        h = rb_hash_uint(h, NUM2LONG(n));
     }
     h = rb_hash_end(h);
     return ST2FIX(h);
@@ -5123,6 +5413,7 @@ rb_ary_hash(VALUE ary)
  *
  *  Returns +true+ if for some index +i+ in +self+, <tt>obj == self[i]</tt>;
  *  otherwise +false+:
+ *
  *    [0, 1, 2].include?(2) # => true
  *    [0, 1, 2].include?(3) # => false
  */
@@ -5134,10 +5425,10 @@ rb_ary_includes(VALUE ary, VALUE item)
     VALUE e;
 
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	e = RARRAY_AREF(ary, i);
-	if (rb_equal(e, item)) {
-	    return Qtrue;
-	}
+        e = RARRAY_AREF(ary, i);
+        if (rb_equal(e, item)) {
+            return Qtrue;
+        }
     }
     return Qfalse;
 }
@@ -5149,10 +5440,10 @@ rb_ary_includes_by_eql(VALUE ary, VALUE item)
     VALUE e;
 
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	e = RARRAY_AREF(ary, i);
-	if (rb_eql(item, e)) {
-	    return Qtrue;
-	}
+        e = RARRAY_AREF(ary, i);
+        if (rb_eql(item, e)) {
+            return Qtrue;
+        }
     }
     return Qfalse;
 }
@@ -5165,14 +5456,14 @@ recursive_cmp(VALUE ary1, VALUE ary2, int recur)
     if (recur) return Qundef;	/* Subtle! */
     len = RARRAY_LEN(ary1);
     if (len > RARRAY_LEN(ary2)) {
-	len = RARRAY_LEN(ary2);
+        len = RARRAY_LEN(ary2);
     }
     for (i=0; i<len; i++) {
-	VALUE e1 = rb_ary_elt(ary1, i), e2 = rb_ary_elt(ary2, i);
-	VALUE v = rb_funcallv(e1, id_cmp, 1, &e2);
-	if (v != INT2FIX(0)) {
-	    return v;
-	}
+        VALUE e1 = rb_ary_elt(ary1, i), e2 = rb_ary_elt(ary2, i);
+        VALUE v = rb_funcallv(e1, id_cmp, 1, &e2);
+        if (v != INT2FIX(0)) {
+            return v;
+        }
     }
     return Qundef;
 }
@@ -5185,18 +5476,27 @@ recursive_cmp(VALUE ary1, VALUE ary2, int recur)
  *  For each index +i+ in +self+, evaluates <tt>result = self[i] <=> other_array[i]</tt>.
  *
  *  Returns -1 if any result is -1:
+ *
  *    [0, 1, 2] <=> [0, 1, 3] # => -1
  *
  *  Returns 1 if any result is 1:
+ *
  *    [0, 1, 2] <=> [0, 1, 1] # => 1
  *
  *  When all results are zero:
+ *
  *  - Returns -1 if +array+ is smaller than +other_array+:
+ *
  *      [0, 1, 2] <=> [0, 1, 2, 3] # => -1
+ *
  *  - Returns 1 if +array+ is larger than +other_array+:
+ *
  *      [0, 1, 2] <=> [0, 1] # => 1
+ *
  *  - Returns 0 if +array+ and +other_array+ are the same size:
+ *
  *      [0, 1, 2] <=> [0, 1, 2] # => 0
+ *
  */
 
 VALUE
@@ -5209,7 +5509,7 @@ rb_ary_cmp(VALUE ary1, VALUE ary2)
     if (NIL_P(ary2)) return Qnil;
     if (ary1 == ary2) return INT2FIX(0);
     v = rb_exec_recursive_paired(recursive_cmp, ary1, ary2, ary2);
-    if (v != Qundef) return v;
+    if (!UNDEF_P(v)) return v;
     len = RARRAY_LEN(ary1) - RARRAY_LEN(ary2);
     if (len == 0) return INT2FIX(0);
     if (len > 0) return INT2FIX(1);
@@ -5222,8 +5522,8 @@ ary_add_hash(VALUE hash, VALUE ary)
     long i;
 
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	VALUE elt = RARRAY_AREF(ary, i);
-	rb_hash_add_new_element(hash, elt, elt);
+        VALUE elt = RARRAY_AREF(ary, i);
+        rb_hash_add_new_element(hash, elt, elt);
     }
     return hash;
 }
@@ -5251,8 +5551,8 @@ ary_add_hash_by(VALUE hash, VALUE ary)
     long i;
 
     for (i = 0; i < RARRAY_LEN(ary); ++i) {
-	VALUE v = rb_ary_elt(ary, i), k = rb_yield(v);
-	rb_hash_add_new_element(hash, k, v);
+        VALUE v = rb_ary_elt(ary, i), k = rb_yield(v);
+        rb_hash_add_new_element(hash, k, v);
     }
     return hash;
 }
@@ -5270,7 +5570,7 @@ ary_recycle_hash(VALUE hash)
     assert(RBASIC_CLASS(hash) == 0);
     if (RHASH_ST_TABLE_P(hash)) {
         st_table *tbl = RHASH_ST_TABLE(hash);
-	st_free_table(tbl);
+        st_free_table(tbl);
         RHASH_ST_CLEAR(hash);
     }
 }
@@ -5283,6 +5583,7 @@ ary_recycle_hash(VALUE hash)
  *  that are not found in \Array +other_array+;
  *  items are compared using <tt>eql?</tt>;
  *  the order from +array+ is preserved:
+ *
  *    [0, 1, 1, 2, 1, 1, 3, 1, 1] - [1] # => [0, 2, 3]
  *    [0, 1, 2, 3] - [3, 0] # => [1, 2]
  *    [0, 1, 2] - [4] # => [0, 1, 2]
@@ -5290,7 +5591,7 @@ ary_recycle_hash(VALUE hash)
  *  Related: Array#difference.
  */
 
-static VALUE
+VALUE
 rb_ary_diff(VALUE ary1, VALUE ary2)
 {
     VALUE ary3;
@@ -5302,18 +5603,18 @@ rb_ary_diff(VALUE ary1, VALUE ary2)
     ary3 = rb_ary_new();
 
     if (RARRAY_LEN(ary1) <= SMALL_ARRAY_LEN || RARRAY_LEN(ary2) <= SMALL_ARRAY_LEN) {
-	for (i=0; i<RARRAY_LEN(ary1); i++) {
-	    VALUE elt = rb_ary_elt(ary1, i);
-	    if (rb_ary_includes_by_eql(ary2, elt)) continue;
-	    rb_ary_push(ary3, elt);
-	}
-	return ary3;
+        for (i=0; i<RARRAY_LEN(ary1); i++) {
+            VALUE elt = rb_ary_elt(ary1, i);
+            if (rb_ary_includes_by_eql(ary2, elt)) continue;
+            rb_ary_push(ary3, elt);
+        }
+        return ary3;
     }
 
     hash = ary_make_hash(ary2);
     for (i=0; i<RARRAY_LEN(ary1); i++) {
         if (rb_hash_stlike_lookup(hash, RARRAY_AREF(ary1, i), NULL)) continue;
-	rb_ary_push(ary3, rb_ary_elt(ary1, i));
+        rb_ary_push(ary3, rb_ary_elt(ary1, i));
     }
     ary_recycle_hash(hash);
     return ary3;
@@ -5326,6 +5627,7 @@ rb_ary_diff(VALUE ary1, VALUE ary2)
  *  Returns a new \Array containing only those elements from +self+
  *  that are not found in any of the Arrays +other_arrays+;
  *  items are compared using <tt>eql?</tt>;  order from +self+ is preserved:
+ *
  *    [0, 1, 1, 2, 1, 1, 3, 1, 1].difference([1]) # => [0, 2, 3]
  *    [0, 1, 2, 3].difference([3, 0], [1, 3]) # => [2]
  *    [0, 1, 2].difference([4]) # => [0, 1, 2]
@@ -5378,10 +5680,12 @@ rb_ary_difference_multi(int argc, VALUE *argv, VALUE ary)
  *
  *  Returns a new \Array containing each element found in both +array+ and \Array +other_array+;
  *  duplicates are omitted; items are compared using <tt>eql?</tt>:
+ *
  *    [0, 1, 2, 3] & [1, 2] # => [1, 2]
  *    [0, 1, 0, 1] & [0, 1] # => [0, 1]
  *
  *  Preserves order from +array+:
+ *
  *    [0, 1, 2] & [3, 2, 1, 0] # => [0, 1, 2]
  *
  *  Related: Array#intersection.
@@ -5400,23 +5704,23 @@ rb_ary_and(VALUE ary1, VALUE ary2)
     if (RARRAY_LEN(ary1) == 0 || RARRAY_LEN(ary2) == 0) return ary3;
 
     if (RARRAY_LEN(ary1) <= SMALL_ARRAY_LEN && RARRAY_LEN(ary2) <= SMALL_ARRAY_LEN) {
-	for (i=0; i<RARRAY_LEN(ary1); i++) {
-	    v = RARRAY_AREF(ary1, i);
-	    if (!rb_ary_includes_by_eql(ary2, v)) continue;
-	    if (rb_ary_includes_by_eql(ary3, v)) continue;
-	    rb_ary_push(ary3, v);
-	}
-	return ary3;
+        for (i=0; i<RARRAY_LEN(ary1); i++) {
+            v = RARRAY_AREF(ary1, i);
+            if (!rb_ary_includes_by_eql(ary2, v)) continue;
+            if (rb_ary_includes_by_eql(ary3, v)) continue;
+            rb_ary_push(ary3, v);
+        }
+        return ary3;
     }
 
     hash = ary_make_hash(ary2);
 
     for (i=0; i<RARRAY_LEN(ary1); i++) {
-	v = RARRAY_AREF(ary1, i);
-	vv = (st_data_t)v;
+        v = RARRAY_AREF(ary1, i);
+        vv = (st_data_t)v;
         if (rb_hash_stlike_delete(hash, &vv, 0)) {
-	    rb_ary_push(ary3, v);
-	}
+            rb_ary_push(ary3, v);
+        }
     }
     ary_recycle_hash(hash);
 
@@ -5430,10 +5734,12 @@ rb_ary_and(VALUE ary1, VALUE ary2)
  *  Returns a new \Array containing each element found both in +self+
  *  and in all of the given Arrays +other_arrays+;
  *  duplicates are omitted; items are compared using <tt>eql?</tt>:
+ *
  *    [0, 1, 2, 3].intersection([0, 1, 2], [0, 1, 3]) # => [0, 1]
  *    [0, 0, 1, 1, 2, 3].intersection([0, 1, 2], [0, 1, 3]) # => [0, 1]
  *
  *  Preserves order from +self+:
+ *
  *    [0, 1, 2].intersection([2, 1, 0]) # => [0, 1, 2]
  *
  *  Returns a copy of +self+ if no arguments given.
@@ -5492,6 +5798,7 @@ rb_ary_union_hash(VALUE hash, VALUE ary2)
  *  Returns the union of +array+ and \Array +other_array+;
  *  duplicates are removed; order is preserved;
  *  items are compared using <tt>eql?</tt>:
+ *
  *    [0, 1] | [2, 3] # => [0, 1, 2, 3]
  *    [0, 1, 1] | [2, 2, 3] # => [0, 1, 2, 3]
  *    [0, 1, 2] | [3, 2, 1, 0] # => [0, 1, 2, 3]
@@ -5506,10 +5813,10 @@ rb_ary_or(VALUE ary1, VALUE ary2)
 
     ary2 = to_ary(ary2);
     if (RARRAY_LEN(ary1) + RARRAY_LEN(ary2) <= SMALL_ARRAY_LEN) {
-	ary3 = rb_ary_new();
+        ary3 = rb_ary_new();
         rb_ary_union(ary3, ary1);
         rb_ary_union(ary3, ary2);
-	return ary3;
+        return ary3;
     }
 
     hash = ary_make_hash(ary1);
@@ -5526,6 +5833,7 @@ rb_ary_or(VALUE ary1, VALUE ary2)
  *
  *  Returns a new \Array that is the union of +self+ and all given Arrays +other_arrays+;
  *  duplicates are removed;  order is preserved;  items are compared using <tt>eql?</tt>:
+ *
  *    [0, 1, 2, 3].union([4, 5], [6, 7]) # => [0, 1, 2, 3, 4, 5, 6, 7]
  *    [0, 1, 1].union([2, 1], [3, 1]) # => [0, 1, 2, 3]
  *    [0, 1, 2, 3].union([3, 2], [1, 0]) # => [0, 1, 2, 3]
@@ -5570,13 +5878,14 @@ rb_ary_union_multi(int argc, VALUE *argv, VALUE ary)
  *     ary.intersect?(other_ary)   -> true or false
  *
  *  Returns +true+ if the array and +other_ary+ have at least one element in
- *  common, otherwise returns +false+.
+ *  common, otherwise returns +false+:
  *
  *     a = [ 1, 2, 3 ]
  *     b = [ 3, 4, 5 ]
  *     c = [ 5, 6, 7 ]
  *     a.intersect?(b)   #=> true
  *     a.intersect?(c)   #=> false
+ *
  */
 
 static VALUE
@@ -5717,6 +6026,7 @@ ary_max_opt_string(VALUE ary, long i, VALUE vmax)
  *    array.max(n) {|a, b| ... } -> new_array
  *
  *  Returns one of the following:
+ *
  *  - The maximum-valued element from +self+.
  *  - A new \Array of maximum-valued elements selected from +self+.
  *
@@ -5725,10 +6035,12 @@ ary_max_opt_string(VALUE ary, long i, VALUE vmax)
  *
  *  With no argument and no block, returns the element in +self+
  *  having the maximum value per method <tt><=></tt>:
+ *
  *    [0, 1, 2].max # => 2
  *
  *  With an argument \Integer +n+ and no block, returns a new \Array with at most +n+ elements,
  *  in descending order per method <tt><=></tt>:
+ *
  *    [0, 1, 2, 3].max(3) # => [3, 2, 1]
  *    [0, 1, 2, 3].max(6) # => [3, 2, 1, 0]
  *
@@ -5736,16 +6048,18 @@ ary_max_opt_string(VALUE ary, long i, VALUE vmax)
  *
  *  With a block and no argument, calls the block <tt>self.size-1</tt> times to compare elements;
  *  returns the element having the maximum value per the block:
+ *
  *    ['0', '00', '000'].max {|a, b| a.size <=> b.size } # => "000"
  *
  *  With an argument +n+ and a block, returns a new \Array with at most +n+ elements,
  *  in descending order per the block:
+ *
  *    ['0', '00', '000'].max(2) {|a, b| a.size <=> b.size } # => ["000", "00"]
+ *
  */
 static VALUE
 rb_ary_max(int argc, VALUE *argv, VALUE ary)
 {
-    struct cmp_opt_data cmp_opt = { 0, 0 };
     VALUE result = Qundef, v;
     VALUE num;
     long i;
@@ -5755,23 +6069,23 @@ rb_ary_max(int argc, VALUE *argv, VALUE ary)
 
     const long n = RARRAY_LEN(ary);
     if (rb_block_given_p()) {
-	for (i = 0; i < RARRAY_LEN(ary); i++) {
-	   v = RARRAY_AREF(ary, i);
-	   if (result == Qundef || rb_cmpint(rb_yield_values(2, v, result), v, result) > 0) {
-	       result = v;
-	   }
-	}
+        for (i = 0; i < RARRAY_LEN(ary); i++) {
+           v = RARRAY_AREF(ary, i);
+           if (UNDEF_P(result) || rb_cmpint(rb_yield_values(2, v, result), v, result) > 0) {
+               result = v;
+           }
+        }
     }
     else if (n > 0) {
         result = RARRAY_AREF(ary, 0);
         if (n > 1) {
-            if (FIXNUM_P(result) && CMP_OPTIMIZABLE(cmp_opt, Integer)) {
+            if (FIXNUM_P(result) && CMP_OPTIMIZABLE(INTEGER)) {
                 return ary_max_opt_fixnum(ary, 1, result);
             }
-            else if (STRING_P(result) && CMP_OPTIMIZABLE(cmp_opt, String)) {
+            else if (STRING_P(result) && CMP_OPTIMIZABLE(STRING)) {
                 return ary_max_opt_string(ary, 1, result);
             }
-            else if (RB_FLOAT_TYPE_P(result) && CMP_OPTIMIZABLE(cmp_opt, Float)) {
+            else if (RB_FLOAT_TYPE_P(result) && CMP_OPTIMIZABLE(FLOAT)) {
                 return ary_max_opt_float(ary, 1, result);
             }
             else {
@@ -5779,7 +6093,7 @@ rb_ary_max(int argc, VALUE *argv, VALUE ary)
             }
         }
     }
-    if (result == Qundef) return Qnil;
+    if (UNDEF_P(result)) return Qnil;
     return result;
 }
 
@@ -5880,6 +6194,7 @@ ary_min_opt_string(VALUE ary, long i, VALUE vmin)
  *    array.min(n) { |a, b| ... } -> new_array
  *
  *  Returns one of the following:
+ *
  *  - The minimum-valued element from +self+.
  *  - A new \Array of minimum-valued elements selected from +self+.
  *
@@ -5888,10 +6203,12 @@ ary_min_opt_string(VALUE ary, long i, VALUE vmin)
  *
  *  With no argument and no block, returns the element in +self+
  *  having the minimum value per method <tt><=></tt>:
+ *
  *    [0, 1, 2].min # => 0
  *
  *  With \Integer argument +n+ and no block, returns a new \Array with at most +n+ elements,
  *  in ascending order per method <tt><=></tt>:
+ *
  *    [0, 1, 2, 3].min(3) # => [0, 1, 2]
  *    [0, 1, 2, 3].min(6) # => [0, 1, 2, 3]
  *
@@ -5899,16 +6216,18 @@ ary_min_opt_string(VALUE ary, long i, VALUE vmin)
  *
  *  With a block and no argument, calls the block <tt>self.size-1</tt> times to compare elements;
  *  returns the element having the minimum value per the block:
+ *
  *    ['0', '00', '000'].min { |a, b| a.size <=> b.size } # => "0"
  *
  *  With an argument +n+ and a block, returns a new \Array with at most +n+ elements,
  *  in ascending order per the block:
+ *
  *    ['0', '00', '000'].min(2) {|a, b| a.size <=> b.size } # => ["0", "00"]
+ *
  */
 static VALUE
 rb_ary_min(int argc, VALUE *argv, VALUE ary)
 {
-    struct cmp_opt_data cmp_opt = { 0, 0 };
     VALUE result = Qundef, v;
     VALUE num;
     long i;
@@ -5918,23 +6237,23 @@ rb_ary_min(int argc, VALUE *argv, VALUE ary)
 
     const long n = RARRAY_LEN(ary);
     if (rb_block_given_p()) {
-	for (i = 0; i < RARRAY_LEN(ary); i++) {
-	   v = RARRAY_AREF(ary, i);
-	   if (result == Qundef || rb_cmpint(rb_yield_values(2, v, result), v, result) < 0) {
-	       result = v;
-	   }
-	}
+        for (i = 0; i < RARRAY_LEN(ary); i++) {
+           v = RARRAY_AREF(ary, i);
+           if (UNDEF_P(result) || rb_cmpint(rb_yield_values(2, v, result), v, result) < 0) {
+               result = v;
+           }
+        }
     }
     else if (n > 0) {
         result = RARRAY_AREF(ary, 0);
         if (n > 1) {
-            if (FIXNUM_P(result) && CMP_OPTIMIZABLE(cmp_opt, Integer)) {
+            if (FIXNUM_P(result) && CMP_OPTIMIZABLE(INTEGER)) {
                 return ary_min_opt_fixnum(ary, 1, result);
             }
-            else if (STRING_P(result) && CMP_OPTIMIZABLE(cmp_opt, String)) {
+            else if (STRING_P(result) && CMP_OPTIMIZABLE(STRING)) {
                 return ary_min_opt_string(ary, 1, result);
             }
-            else if (RB_FLOAT_TYPE_P(result) && CMP_OPTIMIZABLE(cmp_opt, Float)) {
+            else if (RB_FLOAT_TYPE_P(result) && CMP_OPTIMIZABLE(FLOAT)) {
                 return ary_min_opt_float(ary, 1, result);
             }
             else {
@@ -5942,7 +6261,7 @@ rb_ary_min(int argc, VALUE *argv, VALUE ary)
             }
         }
     }
-    if (result == Qundef) return Qnil;
+    if (UNDEF_P(result)) return Qnil;
     return result;
 }
 
@@ -5958,13 +6277,16 @@ rb_ary_min(int argc, VALUE *argv, VALUE ary)
  *  with an \Integer;
  *  returns a new 2-element \Array containing the minimum and maximum values
  *  from +self+, per method <tt><=></tt>:
+ *
  *    [0, 1, 2].minmax # => [0, 2]
  *
  *  When a block is given, the block must return an \Integer;
  *  the block is called <tt>self.size-1</tt> times to compare elements;
  *  returns a new 2-element \Array containing the minimum and maximum values
  *  from +self+, per the block:
+ *
  *    ['0', '00', '000'].minmax {|a, b| a.size <=> b.size } # => ["0", "000"]
+ *
  */
 static VALUE
 rb_ary_minmax(VALUE ary)
@@ -5994,6 +6316,7 @@ push_value(st_data_t key, st_data_t val, st_data_t ary)
  *  to compare.
  *
  *  Returns +self+ if any elements removed:
+ *
  *    a = [0, 0, 1, 1, 2, 2]
  *    a.uniq! # => [0, 1, 2]
  *
@@ -6004,6 +6327,7 @@ push_value(st_data_t key, st_data_t val, st_data_t ary)
  *  elements for which the block returns duplicate values.
  *
  *  Returns +self+ if any elements removed:
+ *
  *    a = ['a', 'aa', 'aaa', 'b', 'bb', 'bbb']
  *    a.uniq! {|element| element.size } # => ['a', 'aa', 'aaa']
  *
@@ -6019,19 +6343,19 @@ rb_ary_uniq_bang(VALUE ary)
     if (RARRAY_LEN(ary) <= 1)
         return Qnil;
     if (rb_block_given_p())
-	hash = ary_make_hash_by(ary);
+        hash = ary_make_hash_by(ary);
     else
-	hash = ary_make_hash(ary);
+        hash = ary_make_hash(ary);
 
     hash_size = RHASH_SIZE(hash);
     if (RARRAY_LEN(ary) == hash_size) {
-	return Qnil;
+        return Qnil;
     }
     rb_ary_modify_check(ary);
     ARY_SET_LEN(ary, 0);
     if (ARY_SHARED_P(ary) && !ARY_EMBED_P(ary)) {
-	rb_ary_unshare(ary);
-	FL_SET_EMBED(ary);
+        rb_ary_unshare(ary);
+        FL_SET_EMBED(ary);
     }
     ary_resize_capa(ary, hash_size);
     rb_hash_foreach(hash, push_value, ary);
@@ -6049,15 +6373,18 @@ rb_ary_uniq_bang(VALUE ary)
  *  the first occurrence always being retained.
  *
  *  With no block given, identifies and omits duplicates using method <tt>eql?</tt>
- *  to compare.
+ *  to compare:
+ *
  *    a = [0, 0, 1, 1, 2, 2]
  *    a.uniq # => [0, 1, 2]
  *
  *  With a block given, calls the block for each element;
  *  identifies (using method <tt>eql?</tt>) and omits duplicate values,
  *  that is, those elements for which the block returns the same value:
+ *
  *    a = ['a', 'aa', 'aaa', 'b', 'bb', 'bbb']
  *    a.uniq {|element| element.size } # => ["a", "aa", "aaa"]
+ *
  */
 
 static VALUE
@@ -6070,12 +6397,12 @@ rb_ary_uniq(VALUE ary)
         uniq = rb_ary_dup(ary);
     }
     else if (rb_block_given_p()) {
-	hash = ary_make_hash_by(ary);
-	uniq = rb_hash_values(hash);
+        hash = ary_make_hash_by(ary);
+        uniq = rb_hash_values(hash);
     }
     else {
-	hash = ary_make_hash(ary);
-	uniq = rb_hash_values(hash);
+        hash = ary_make_hash(ary);
+        uniq = rb_hash_values(hash);
     }
     if (hash) {
         ary_recycle_hash(hash);
@@ -6104,12 +6431,12 @@ rb_ary_compact_bang(VALUE ary)
     end = p + RARRAY_LEN(ary);
 
     while (t < end) {
-	if (NIL_P(*t)) t++;
-	else *p++ = *t++;
+        if (NIL_P(*t)) t++;
+        else *p++ = *t++;
     }
     n = p - RARRAY_CONST_PTR_TRANSIENT(ary);
     if (RARRAY_LEN(ary) == n) {
-	return Qnil;
+        return Qnil;
     }
     ary_resize_smaller(ary, n);
 
@@ -6121,6 +6448,7 @@ rb_ary_compact_bang(VALUE ary)
  *    array.compact -> new_array
  *
  *  Returns a new \Array containing all non-+nil+ elements from +self+:
+ *
  *    a = [nil, 0, nil, 1, nil, 2, nil]
  *    a.compact # => [0, 1, 2]
  */
@@ -6142,19 +6470,22 @@ rb_ary_compact(VALUE ary)
  *  Returns a count of specified elements.
  *
  *  With no argument and no block, returns the count of all elements:
+ *
  *    [0, 1, 2].count # => 3
  *    [].count # => 0
  *
  *  With argument +obj+, returns the count of elements <tt>==</tt> to +obj+:
+ *
  *    [0, 1, 2, 0.0].count(0) # => 2
  *    [0, 1, 2].count(3) # => 0
  *
  *  With no argument and a block given, calls the block with each element;
  *  returns the count of elements for which the block returns a truthy value:
+ *
  *    [0, 1, 2, 3].count {|element| element > 1} # => 2
  *
  *  With argument +obj+ and a block given, issues a warning, ignores the block,
- *  and returns the count of elements <tt>==</tt> to +obj+:
+ *  and returns the count of elements <tt>==</tt> to +obj+.
  */
 
 static VALUE
@@ -6163,25 +6494,25 @@ rb_ary_count(int argc, VALUE *argv, VALUE ary)
     long i, n = 0;
 
     if (rb_check_arity(argc, 0, 1) == 0) {
-	VALUE v;
+        VALUE v;
 
-	if (!rb_block_given_p())
-	    return LONG2NUM(RARRAY_LEN(ary));
+        if (!rb_block_given_p())
+            return LONG2NUM(RARRAY_LEN(ary));
 
-	for (i = 0; i < RARRAY_LEN(ary); i++) {
-	    v = RARRAY_AREF(ary, i);
-	    if (RTEST(rb_yield(v))) n++;
-	}
+        for (i = 0; i < RARRAY_LEN(ary); i++) {
+            v = RARRAY_AREF(ary, i);
+            if (RTEST(rb_yield(v))) n++;
+        }
     }
     else {
         VALUE obj = argv[0];
 
-	if (rb_block_given_p()) {
-	    rb_warn("given block not used");
-	}
-	for (i = 0; i < RARRAY_LEN(ary); i++) {
-	    if (rb_equal(RARRAY_AREF(ary, i), obj)) n++;
-	}
+        if (rb_block_given_p()) {
+            rb_warn("given block not used");
+        }
+        for (i = 0; i < RARRAY_LEN(ary); i++) {
+            if (rb_equal(RARRAY_AREF(ary, i), obj)) n++;
+        }
     }
 
     return LONG2NUM(n);
@@ -6215,64 +6546,64 @@ flatten(VALUE ary, int level)
     rb_ary_push(stack, LONG2NUM(i + 1));
 
     if (level < 0) {
-	vmemo = rb_hash_new();
-	RBASIC_CLEAR_CLASS(vmemo);
-	memo = st_init_numtable();
-	rb_hash_st_table_set(vmemo, memo);
-	st_insert(memo, (st_data_t)ary, (st_data_t)Qtrue);
-	st_insert(memo, (st_data_t)tmp, (st_data_t)Qtrue);
+        vmemo = rb_hash_new();
+        RBASIC_CLEAR_CLASS(vmemo);
+        memo = st_init_numtable();
+        rb_hash_st_table_set(vmemo, memo);
+        st_insert(memo, (st_data_t)ary, (st_data_t)Qtrue);
+        st_insert(memo, (st_data_t)tmp, (st_data_t)Qtrue);
     }
 
     ary = tmp;
     i = 0;
 
     while (1) {
-	while (i < RARRAY_LEN(ary)) {
-	    elt = RARRAY_AREF(ary, i++);
-	    if (level >= 0 && RARRAY_LEN(stack) / 2 >= level) {
-		rb_ary_push(result, elt);
-		continue;
-	    }
-	    tmp = rb_check_array_type(elt);
-	    if (RBASIC(result)->klass) {
-		if (memo) {
-		    RB_GC_GUARD(vmemo);
-		    st_clear(memo);
-		}
-		rb_raise(rb_eRuntimeError, "flatten reentered");
-	    }
-	    if (NIL_P(tmp)) {
-		rb_ary_push(result, elt);
-	    }
-	    else {
-		if (memo) {
-		    id = (st_data_t)tmp;
-		    if (st_is_member(memo, id)) {
-			st_clear(memo);
-			rb_raise(rb_eArgError, "tried to flatten recursive array");
-		    }
-		    st_insert(memo, id, (st_data_t)Qtrue);
-		}
-		rb_ary_push(stack, ary);
-		rb_ary_push(stack, LONG2NUM(i));
-		ary = tmp;
-		i = 0;
-	    }
-	}
-	if (RARRAY_LEN(stack) == 0) {
-	    break;
-	}
-	if (memo) {
-	    id = (st_data_t)ary;
-	    st_delete(memo, &id, 0);
-	}
-	tmp = rb_ary_pop(stack);
-	i = NUM2LONG(tmp);
-	ary = rb_ary_pop(stack);
+        while (i < RARRAY_LEN(ary)) {
+            elt = RARRAY_AREF(ary, i++);
+            if (level >= 0 && RARRAY_LEN(stack) / 2 >= level) {
+                rb_ary_push(result, elt);
+                continue;
+            }
+            tmp = rb_check_array_type(elt);
+            if (RBASIC(result)->klass) {
+                if (memo) {
+                    RB_GC_GUARD(vmemo);
+                    st_clear(memo);
+                }
+                rb_raise(rb_eRuntimeError, "flatten reentered");
+            }
+            if (NIL_P(tmp)) {
+                rb_ary_push(result, elt);
+            }
+            else {
+                if (memo) {
+                    id = (st_data_t)tmp;
+                    if (st_is_member(memo, id)) {
+                        st_clear(memo);
+                        rb_raise(rb_eArgError, "tried to flatten recursive array");
+                    }
+                    st_insert(memo, id, (st_data_t)Qtrue);
+                }
+                rb_ary_push(stack, ary);
+                rb_ary_push(stack, LONG2NUM(i));
+                ary = tmp;
+                i = 0;
+            }
+        }
+        if (RARRAY_LEN(stack) == 0) {
+            break;
+        }
+        if (memo) {
+            id = (st_data_t)ary;
+            st_delete(memo, &id, 0);
+        }
+        tmp = rb_ary_pop(stack);
+        i = NUM2LONG(tmp);
+        ary = rb_ary_pop(stack);
     }
 
     if (memo) {
-	st_clear(memo);
+        st_clear(memo);
     }
 
     RBASIC_SET_CLASS(result, rb_cArray);
@@ -6288,6 +6619,7 @@ flatten(VALUE ary, int level)
  *  returns +self+ if any changes, +nil+ otherwise.
  *
  *  With non-negative \Integer argument +level+, flattens recursively through +level+ levels:
+ *
  *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
  *    a.flatten!(1) # => [0, 1, [2, 3], 4, 5]
  *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
@@ -6297,6 +6629,7 @@ flatten(VALUE ary, int level)
  *    [0, 1, 2].flatten!(1) # => nil
  *
  *  With no argument, a +nil+ argument, or with negative argument +level+, flattens all levels:
+ *
  *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
  *    a.flatten! # => [0, 1, 2, 3, 4, 5]
  *    [0, 1, 2].flatten! # => nil
@@ -6305,6 +6638,7 @@ flatten(VALUE ary, int level)
  *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
  *    a.flatten!(-2) # => [0, 1, 2, 3, 4, 5]
  *    [0, 1, 2].flatten!(-1) # => nil
+ *
  */
 
 static VALUE
@@ -6320,7 +6654,7 @@ rb_ary_flatten_bang(int argc, VALUE *argv, VALUE ary)
 
     result = flatten(ary, level);
     if (result == ary) {
-	return Qnil;
+        return Qnil;
     }
     if (!(mod = ARY_EMBED_P(result))) rb_obj_freeze(result);
     rb_ary_replace(ary, result);
@@ -6339,6 +6673,7 @@ rb_ary_flatten_bang(int argc, VALUE *argv, VALUE ary)
  *  - Each \Array is replaced by its individual elements.
  *
  *  With non-negative \Integer argument +level+, flattens recursively through +level+ levels:
+ *
  *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
  *    a.flatten(0) # => [0, [1, [2, 3], 4], 5]
  *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
@@ -6349,6 +6684,7 @@ rb_ary_flatten_bang(int argc, VALUE *argv, VALUE ary)
  *    a.flatten(3) # => [0, 1, 2, 3, 4, 5]
  *
  *  With no argument, a +nil+ argument, or with negative argument +level+, flattens all levels:
+ *
  *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
  *    a.flatten # => [0, 1, 2, 3, 4, 5]
  *    [0, 1, 2].flatten # => [0, 1, 2]
@@ -6357,6 +6693,7 @@ rb_ary_flatten_bang(int argc, VALUE *argv, VALUE ary)
  *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
  *    a.flatten(-2) # => [0, 1, 2, 3, 4, 5]
  *    [0, 1, 2].flatten(-1) # => [0, 1, 2]
+ *
  */
 
 static VALUE
@@ -6388,16 +6725,16 @@ rb_ary_shuffle_bang(rb_execution_context_t *ec, VALUE ary, VALUE randgen)
     rb_ary_modify(ary);
     i = len = RARRAY_LEN(ary);
     RARRAY_PTR_USE(ary, ptr, {
-	while (i) {
-	    long j = RAND_UPTO(i);
-	    VALUE tmp;
+        while (i) {
+            long j = RAND_UPTO(i);
+            VALUE tmp;
             if (len != RARRAY_LEN(ary) || ptr != RARRAY_CONST_PTR_TRANSIENT(ary)) {
                 rb_raise(rb_eRuntimeError, "modified during shuffle");
-	    }
-	    tmp = ptr[--i];
-	    ptr[i] = ptr[j];
-	    ptr[j] = tmp;
-	}
+            }
+            tmp = ptr[--i];
+            ptr[i] = ptr[j];
+            ptr[j] = tmp;
+        }
     }); /* WB: no new reference */
     return ary;
 }
@@ -6420,120 +6757,120 @@ ary_sample(rb_execution_context_t *ec, VALUE ary, VALUE randgen, VALUE nv, VALUE
 
     len = RARRAY_LEN(ary);
     if (!to_array) {
-	if (len < 2)
-	    i = 0;
-	else
-	    i = RAND_UPTO(len);
+        if (len < 2)
+            i = 0;
+        else
+            i = RAND_UPTO(len);
 
-	return rb_ary_elt(ary, i);
+        return rb_ary_elt(ary, i);
     }
     n = NUM2LONG(nv);
     if (n < 0) rb_raise(rb_eArgError, "negative sample number");
     if (n > len) n = len;
     if (n <= numberof(idx)) {
-	for (i = 0; i < n; ++i) {
-	    rnds[i] = RAND_UPTO(len - i);
-	}
+        for (i = 0; i < n; ++i) {
+            rnds[i] = RAND_UPTO(len - i);
+        }
     }
     k = len;
     len = RARRAY_LEN(ary);
     if (len < k && n <= numberof(idx)) {
-	for (i = 0; i < n; ++i) {
-	    if (rnds[i] >= len) return rb_ary_new_capa(0);
-	}
+        for (i = 0; i < n; ++i) {
+            if (rnds[i] >= len) return rb_ary_new_capa(0);
+        }
     }
     if (n > len) n = len;
     switch (n) {
       case 0:
-	return rb_ary_new_capa(0);
+        return rb_ary_new_capa(0);
       case 1:
-	i = rnds[0];
-	return rb_ary_new_from_args(1, RARRAY_AREF(ary, i));
+        i = rnds[0];
+        return rb_ary_new_from_args(1, RARRAY_AREF(ary, i));
       case 2:
-	i = rnds[0];
-	j = rnds[1];
-	if (j >= i) j++;
-	return rb_ary_new_from_args(2, RARRAY_AREF(ary, i), RARRAY_AREF(ary, j));
+        i = rnds[0];
+        j = rnds[1];
+        if (j >= i) j++;
+        return rb_ary_new_from_args(2, RARRAY_AREF(ary, i), RARRAY_AREF(ary, j));
       case 3:
-	i = rnds[0];
-	j = rnds[1];
-	k = rnds[2];
-	{
-	    long l = j, g = i;
-	    if (j >= i) l = i, g = ++j;
-	    if (k >= l && (++k >= g)) ++k;
-	}
-	return rb_ary_new_from_args(3, RARRAY_AREF(ary, i), RARRAY_AREF(ary, j), RARRAY_AREF(ary, k));
+        i = rnds[0];
+        j = rnds[1];
+        k = rnds[2];
+        {
+            long l = j, g = i;
+            if (j >= i) l = i, g = ++j;
+            if (k >= l && (++k >= g)) ++k;
+        }
+        return rb_ary_new_from_args(3, RARRAY_AREF(ary, i), RARRAY_AREF(ary, j), RARRAY_AREF(ary, k));
     }
     memo_threshold =
-	len < 2560 ? len / 128 :
-	len < 5120 ? len / 64 :
-	len < 10240 ? len / 32 :
-	len / 16;
+        len < 2560 ? len / 128 :
+        len < 5120 ? len / 64 :
+        len < 10240 ? len / 32 :
+        len / 16;
     if (n <= numberof(idx)) {
-	long sorted[numberof(idx)];
-	sorted[0] = idx[0] = rnds[0];
-	for (i=1; i<n; i++) {
-	    k = rnds[i];
-	    for (j = 0; j < i; ++j) {
-		if (k < sorted[j]) break;
-		++k;
-	    }
-	    memmove(&sorted[j+1], &sorted[j], sizeof(sorted[0])*(i-j));
-	    sorted[j] = idx[i] = k;
-	}
-	result = rb_ary_new_capa(n);
+        long sorted[numberof(idx)];
+        sorted[0] = idx[0] = rnds[0];
+        for (i=1; i<n; i++) {
+            k = rnds[i];
+            for (j = 0; j < i; ++j) {
+                if (k < sorted[j]) break;
+                ++k;
+            }
+            memmove(&sorted[j+1], &sorted[j], sizeof(sorted[0])*(i-j));
+            sorted[j] = idx[i] = k;
+        }
+        result = rb_ary_new_capa(n);
         RARRAY_PTR_USE_TRANSIENT(result, ptr_result, {
-	    for (i=0; i<n; i++) {
-		ptr_result[i] = RARRAY_AREF(ary, idx[i]);
-	    }
-	});
+            for (i=0; i<n; i++) {
+                ptr_result[i] = RARRAY_AREF(ary, idx[i]);
+            }
+        });
     }
     else if (n <= memo_threshold / 2) {
-	long max_idx = 0;
+        long max_idx = 0;
 #undef RUBY_UNTYPED_DATA_WARNING
 #define RUBY_UNTYPED_DATA_WARNING 0
-	VALUE vmemo = Data_Wrap_Struct(0, 0, st_free_table, 0);
-	st_table *memo = st_init_numtable_with_size(n);
-	DATA_PTR(vmemo) = memo;
-	result = rb_ary_new_capa(n);
-	RARRAY_PTR_USE(result, ptr_result, {
-	    for (i=0; i<n; i++) {
-		long r = RAND_UPTO(len-i) + i;
-		ptr_result[i] = r;
-		if (r > max_idx) max_idx = r;
-	    }
-	    len = RARRAY_LEN(ary);
-	    if (len <= max_idx) n = 0;
-	    else if (n > len) n = len;
+        VALUE vmemo = Data_Wrap_Struct(0, 0, st_free_table, 0);
+        st_table *memo = st_init_numtable_with_size(n);
+        DATA_PTR(vmemo) = memo;
+        result = rb_ary_new_capa(n);
+        RARRAY_PTR_USE(result, ptr_result, {
+            for (i=0; i<n; i++) {
+                long r = RAND_UPTO(len-i) + i;
+                ptr_result[i] = r;
+                if (r > max_idx) max_idx = r;
+            }
+            len = RARRAY_LEN(ary);
+            if (len <= max_idx) n = 0;
+            else if (n > len) n = len;
             RARRAY_PTR_USE_TRANSIENT(ary, ptr_ary, {
-		for (i=0; i<n; i++) {
-		    long j2 = j = ptr_result[i];
-		    long i2 = i;
-		    st_data_t value;
-		    if (st_lookup(memo, (st_data_t)i, &value)) i2 = (long)value;
-		    if (st_lookup(memo, (st_data_t)j, &value)) j2 = (long)value;
-		    st_insert(memo, (st_data_t)j, (st_data_t)i2);
-		    ptr_result[i] = ptr_ary[j2];
-		}
-	    });
-	});
-	DATA_PTR(vmemo) = 0;
-	st_free_table(memo);
+                for (i=0; i<n; i++) {
+                    long j2 = j = ptr_result[i];
+                    long i2 = i;
+                    st_data_t value;
+                    if (st_lookup(memo, (st_data_t)i, &value)) i2 = (long)value;
+                    if (st_lookup(memo, (st_data_t)j, &value)) j2 = (long)value;
+                    st_insert(memo, (st_data_t)j, (st_data_t)i2);
+                    ptr_result[i] = ptr_ary[j2];
+                }
+            });
+        });
+        DATA_PTR(vmemo) = 0;
+        st_free_table(memo);
     }
     else {
-	result = rb_ary_dup(ary);
-	RBASIC_CLEAR_CLASS(result);
-	RB_GC_GUARD(ary);
-	RARRAY_PTR_USE(result, ptr_result, {
-	    for (i=0; i<n; i++) {
-		j = RAND_UPTO(len-i) + i;
-		nv = ptr_result[j];
-		ptr_result[j] = ptr_result[i];
-		ptr_result[i] = nv;
-	    }
-	});
-	RBASIC_SET_CLASS_RAW(result, rb_cArray);
+        result = rb_ary_dup(ary);
+        RBASIC_CLEAR_CLASS(result);
+        RB_GC_GUARD(ary);
+        RARRAY_PTR_USE(result, ptr_result, {
+            for (i=0; i<n; i++) {
+                j = RAND_UPTO(len-i) + i;
+                nv = ptr_result[j];
+                ptr_result[j] = ptr_result[i];
+                ptr_result[i] = nv;
+            }
+        });
+        RBASIC_SET_CLASS_RAW(result, rb_cArray);
     }
     ARY_SET_LEN(result, n);
 
@@ -6552,7 +6889,7 @@ rb_ary_cycle_size(VALUE self, VALUE args, VALUE eobj)
     long mul;
     VALUE n = Qnil;
     if (args && (RARRAY_LEN(args) > 0)) {
-	n = RARRAY_AREF(args, 0);
+        n = RARRAY_AREF(args, 0);
     }
     if (RARRAY_LEN(self) == 0) return INT2FIX(0);
     if (NIL_P(n)) return DBL2NUM(HUGE_VAL);
@@ -6572,15 +6909,18 @@ rb_ary_cycle_size(VALUE self, VALUE args, VALUE eobj)
  *  When called with positive \Integer argument +count+ and a block,
  *  calls the block with each element, then does so again,
  *  until it has done so +count+ times; returns +nil+:
+ *
  *    output = []
  *    [0, 1].cycle(2) {|element| output.push(element) } # => nil
  *    output # => [0, 1, 0, 1]
  *
  *  If +count+ is zero or negative, does not call the block:
+ *
  *    [0, 1].cycle(0) {|element| fail 'Cannot happen' } # => nil
  *    [0, 1].cycle(-1) {|element| fail 'Cannot happen' } # => nil
  *
  *  When a block is given, and argument is omitted or +nil+, cycles forever:
+ *
  *    # Prints 0 and 1 forever.
  *    [0, 1].cycle {|element| puts element }
  *    [0, 1].cycle(nil) {|element| puts element }
@@ -6590,6 +6930,7 @@ rb_ary_cycle_size(VALUE self, VALUE args, VALUE eobj)
  *    [0, 1].cycle(2) # => #<Enumerator: [0, 1]:cycle(2)>
  *    [0, 1].cycle # => # => #<Enumerator: [0, 1]:cycle>
  *    [0, 1].cycle.first(5) # => [0, 1, 0, 1, 0]
+ *
  */
 static VALUE
 rb_ary_cycle(int argc, VALUE *argv, VALUE ary)
@@ -6615,9 +6956,6 @@ rb_ary_cycle(int argc, VALUE *argv, VALUE ary)
     return Qnil;
 }
 
-#define tmpary(n) rb_ary_tmp_new(n)
-#define tmpary_discard(a) (ary_discard(a), RBASIC_SET_CLASS_RAW(a, rb_cArray))
-
 /*
  * Build a ruby array of the corresponding values and yield it to the
  * associated block.
@@ -6653,32 +6991,32 @@ permute0(const long n, const long r, long *const p, char *const used, const VALU
     long i = 0, index = 0;
 
     for (;;) {
-	const char *const unused = memchr(&used[i], 0, n-i);
-	if (!unused) {
-	    if (!index) break;
-	    i = p[--index];                /* pop index */
-	    used[i++] = 0;                 /* index unused */
-	}
-	else {
-	    i = unused - used;
-	    p[index] = i;
-	    used[i] = 1;                   /* mark index used */
-	    ++index;
-	    if (index < r-1) {             /* if not done yet */
-		p[index] = i = 0;
-		continue;
-	    }
-	    for (i = 0; i < n; ++i) {
-		if (used[i]) continue;
-		p[index] = i;
-		if (!yield_indexed_values(values, r, p)) {
-		    rb_raise(rb_eRuntimeError, "permute reentered");
-		}
-	    }
-	    i = p[--index];                /* pop index */
-	    used[i] = 0;                   /* index unused */
-	    p[index] = ++i;
-	}
+        const char *const unused = memchr(&used[i], 0, n-i);
+        if (!unused) {
+            if (!index) break;
+            i = p[--index];                /* pop index */
+            used[i++] = 0;                 /* index unused */
+        }
+        else {
+            i = unused - used;
+            p[index] = i;
+            used[i] = 1;                   /* mark index used */
+            ++index;
+            if (index < r-1) {             /* if not done yet */
+                p[index] = i = 0;
+                continue;
+            }
+            for (i = 0; i < n; ++i) {
+                if (used[i]) continue;
+                p[index] = i;
+                if (!yield_indexed_values(values, r, p)) {
+                    rb_raise(rb_eRuntimeError, "permute reentered");
+                }
+            }
+            i = p[--index];                /* pop index */
+            used[i] = 0;                   /* index unused */
+            p[index] = ++i;
+        }
     }
 }
 
@@ -6691,14 +7029,14 @@ descending_factorial(long from, long how_many)
 {
     VALUE cnt;
     if (how_many > 0) {
-	cnt = LONG2FIX(from);
-	while (--how_many > 0) {
-	    long v = --from;
-	    cnt = rb_int_mul(cnt, LONG2FIX(v));
-	}
+        cnt = LONG2FIX(from);
+        while (--how_many > 0) {
+            long v = --from;
+            cnt = rb_int_mul(cnt, LONG2FIX(v));
+        }
     }
     else {
-	cnt = LONG2FIX(how_many == 0);
+        cnt = LONG2FIX(how_many == 0);
     }
     return cnt;
 }
@@ -6709,18 +7047,18 @@ binomial_coefficient(long comb, long size)
     VALUE r;
     long i;
     if (comb > size-comb) {
-	comb = size-comb;
+        comb = size-comb;
     }
     if (comb < 0) {
-	return LONG2FIX(0);
+        return LONG2FIX(0);
     }
     else if (comb == 0) {
-	return LONG2FIX(1);
+        return LONG2FIX(1);
     }
     r = LONG2FIX(size);
     for (i = 1; i < comb; ++i) {
-	r = rb_int_mul(r, LONG2FIX(size - i));
-	r = rb_int_idiv(r, LONG2FIX(i + 1));
+        r = rb_int_mul(r, LONG2FIX(size - i));
+        r = rb_int_idiv(r, LONG2FIX(i + 1));
     }
     return r;
 }
@@ -6748,19 +7086,26 @@ rb_ary_permutation_size(VALUE ary, VALUE args, VALUE eobj)
  *  are given, calls the block with all +n+-tuple permutations of +self+.
  *
  *  Example:
+ *
  *    a = [0, 1, 2]
  *    a.permutation(2) {|permutation| p permutation }
+ *
  *  Output:
+ *
  *    [0, 1]
  *    [0, 2]
  *    [1, 0]
  *    [1, 2]
  *    [2, 0]
  *    [2, 1]
+ *
  *  Another example:
+ *
  *    a = [0, 1, 2]
  *    a.permutation(3) {|permutation| p permutation }
+ *
  *  Output:
+ *
  *    [0, 1, 2]
  *    [0, 2, 1]
  *    [1, 0, 2]
@@ -6769,22 +7114,29 @@ rb_ary_permutation_size(VALUE ary, VALUE args, VALUE eobj)
  *    [2, 1, 0]
  *
  *  When +n+ is zero, calls the block once with a new empty \Array:
+ *
  *    a = [0, 1, 2]
  *    a.permutation(0) {|permutation| p permutation }
+ *
  *  Output:
+ *
  *    []
  *
  *  When +n+ is out of range (negative or larger than <tt>self.size</tt>),
  *  does not call the block:
+ *
  *    a = [0, 1, 2]
  *    a.permutation(-1) {|permutation| fail 'Cannot happen' }
  *    a.permutation(4) {|permutation| fail 'Cannot happen' }
  *
  *  When a block given but no argument,
  *  behaves the same as <tt>a.permutation(a.size)</tt>:
+ *
  *    a = [0, 1, 2]
  *    a.permutation {|permutation| p permutation }
+ *
  *  Output:
+ *
  *    [0, 1, 2]
  *    [0, 2, 1]
  *    [1, 0, 2]
@@ -6793,9 +7145,11 @@ rb_ary_permutation_size(VALUE ary, VALUE args, VALUE eobj)
  *    [2, 1, 0]
  *
  *  Returns a new \Enumerator if no block given:
+ *
  *    a = [0, 1, 2]
  *    a.permutation # => #<Enumerator: [0, 1, 2]:permutation>
  *    a.permutation(2) # => #<Enumerator: [0, 1, 2]:permutation(2)>
+ *
  */
 
 static VALUE
@@ -6810,28 +7164,28 @@ rb_ary_permutation(int argc, VALUE *argv, VALUE ary)
         r = NUM2LONG(argv[0]);            /* Permutation size from argument */
 
     if (r < 0 || n < r) {
-	/* no permutations: yield nothing */
+        /* no permutations: yield nothing */
     }
     else if (r == 0) { /* exactly one permutation: the zero-length array */
-	rb_yield(rb_ary_new2(0));
+        rb_yield(rb_ary_new2(0));
     }
     else if (r == 1) { /* this is a special, easy case */
-	for (i = 0; i < RARRAY_LEN(ary); i++) {
-	    rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
-	}
+        for (i = 0; i < RARRAY_LEN(ary); i++) {
+            rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
+        }
     }
     else {             /* this is the general case */
-	volatile VALUE t0;
-	long *p = ALLOCV_N(long, t0, r+roomof(n, sizeof(long)));
-	char *used = (char*)(p + r);
-	VALUE ary0 = ary_make_shared_copy(ary); /* private defensive copy of ary */
-	RBASIC_CLEAR_CLASS(ary0);
+        volatile VALUE t0;
+        long *p = ALLOCV_N(long, t0, r+roomof(n, sizeof(long)));
+        char *used = (char*)(p + r);
+        VALUE ary0 = ary_make_shared_copy(ary); /* private defensive copy of ary */
+        RBASIC_CLEAR_CLASS(ary0);
 
-	MEMZERO(used, char, n); /* initialize array */
+        MEMZERO(used, char, n); /* initialize array */
 
-	permute0(n, r, p, used, ary0); /* compute and yield permutations */
-	ALLOCV_END(t0);
-	RBASIC_SET_CLASS_RAW(ary0, rb_cArray);
+        permute0(n, r, p, used, ary0); /* compute and yield permutations */
+        ALLOCV_END(t0);
+        RBASIC_SET_CLASS_RAW(ary0, rb_cArray);
     }
     return ary;
 }
@@ -6844,16 +7198,16 @@ combinate0(const long len, const long n, long *const stack, const VALUE values)
     MEMZERO(stack+1, long, n);
     stack[0] = -1;
     for (;;) {
-	for (lev++; lev < n; lev++) {
-	    stack[lev+1] = stack[lev]+1;
-	}
-	if (!yield_indexed_values(values, n, stack+1)) {
-	    rb_raise(rb_eRuntimeError, "combination reentered");
-	}
-	do {
-	    if (lev == 0) return;
-	    stack[lev--]++;
-	} while (stack[lev+1]+n == len+lev+1);
+        for (lev++; lev < n; lev++) {
+            stack[lev+1] = stack[lev]+1;
+        }
+        if (!yield_indexed_values(values, n, stack+1)) {
+            rb_raise(rb_eRuntimeError, "combination reentered");
+        }
+        do {
+            if (lev == 0) return;
+            stack[lev--]++;
+        } while (stack[lev+1]+n == len+lev+1);
     }
 }
 
@@ -6878,34 +7232,46 @@ rb_ary_combination_size(VALUE ary, VALUE args, VALUE eobj)
  *  are given, calls the block with all +n+-tuple combinations of +self+.
  *
  *  Example:
+ *
  *    a = [0, 1, 2]
  *    a.combination(2) {|combination| p combination }
+ *
  *  Output:
+ *
  *    [0, 1]
  *    [0, 2]
  *    [1, 2]
  *
  *  Another example:
+ *
  *    a = [0, 1, 2]
  *    a.combination(3) {|combination| p combination }
+ *
  *  Output:
+ *
  *    [0, 1, 2]
  *
  *  When +n+ is zero, calls the block once with a new empty \Array:
+ *
  *    a = [0, 1, 2]
  *    a1 = a.combination(0) {|combination| p combination }
+ *
  *  Output:
+ *
  *    []
  *
  *  When +n+ is out of range (negative or larger than <tt>self.size</tt>),
  *  does not call the block:
+ *
  *    a = [0, 1, 2]
  *    a.combination(-1) {|combination| fail 'Cannot happen' }
  *    a.combination(4) {|combination| fail 'Cannot happen' }
  *
  *  Returns a new \Enumerator if no block given:
+ *
  *    a = [0, 1, 2]
  *    a.combination(2) # => #<Enumerator: [0, 1, 2]:combination(2)>
+ *
  */
 
 static VALUE
@@ -6917,25 +7283,25 @@ rb_ary_combination(VALUE ary, VALUE num)
     RETURN_SIZED_ENUMERATOR(ary, 1, &num, rb_ary_combination_size);
     len = RARRAY_LEN(ary);
     if (n < 0 || len < n) {
-	/* yield nothing */
+        /* yield nothing */
     }
     else if (n == 0) {
-	rb_yield(rb_ary_new2(0));
+        rb_yield(rb_ary_new2(0));
     }
     else if (n == 1) {
-	for (i = 0; i < RARRAY_LEN(ary); i++) {
-	    rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
-	}
+        for (i = 0; i < RARRAY_LEN(ary); i++) {
+            rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
+        }
     }
     else {
-	VALUE ary0 = ary_make_shared_copy(ary); /* private defensive copy of ary */
-	volatile VALUE t0;
-	long *stack = ALLOCV_N(long, t0, n+1);
+        VALUE ary0 = ary_make_shared_copy(ary); /* private defensive copy of ary */
+        volatile VALUE t0;
+        long *stack = ALLOCV_N(long, t0, n+1);
 
-	RBASIC_CLEAR_CLASS(ary0);
-	combinate0(len, n, stack, ary0);
-	ALLOCV_END(t0);
-	RBASIC_SET_CLASS_RAW(ary0, rb_cArray);
+        RBASIC_CLEAR_CLASS(ary0);
+        combinate0(len, n, stack, ary0);
+        ALLOCV_END(t0);
+        RBASIC_SET_CLASS_RAW(ary0, rb_cArray);
     }
     return ary;
 }
@@ -6959,19 +7325,19 @@ rpermute0(const long n, const long r, long *const p, const VALUE values)
 
     p[index] = i;
     for (;;) {
-	if (++index < r-1) {
-	    p[index] = i = 0;
-	    continue;
-	}
-	for (i = 0; i < n; ++i) {
-	    p[index] = i;
-	    if (!yield_indexed_values(values, r, p)) {
-		rb_raise(rb_eRuntimeError, "repeated permute reentered");
-	    }
-	}
-	do {
-	    if (index <= 0) return;
-	} while ((i = ++p[--index]) >= n);
+        if (++index < r-1) {
+            p[index] = i = 0;
+            continue;
+        }
+        for (i = 0; i < n; ++i) {
+            p[index] = i;
+            if (!yield_indexed_values(values, r, p)) {
+                rb_raise(rb_eRuntimeError, "repeated permute reentered");
+            }
+        }
+        do {
+            if (index <= 0) return;
+        } while ((i = ++p[--index]) >= n);
     }
 }
 
@@ -6982,10 +7348,10 @@ rb_ary_repeated_permutation_size(VALUE ary, VALUE args, VALUE eobj)
     long k = NUM2LONG(RARRAY_AREF(args, 0));
 
     if (k < 0) {
-	return LONG2FIX(0);
+        return LONG2FIX(0);
     }
     if (n <= 0) {
-	return LONG2FIX(!k);
+        return LONG2FIX(!k);
     }
     return rb_int_positive_pow(n, (unsigned long)k);
 }
@@ -7004,16 +7370,22 @@ rb_ary_repeated_permutation_size(VALUE ary, VALUE args, VALUE eobj)
  *  The number of permutations is <tt>self.size**n</tt>.
  *
  *  +n+ = 1:
+ *
  *    a = [0, 1, 2]
  *    a.repeated_permutation(1) {|permutation| p permutation }
+ *
  *  Output:
+ *
  *    [0]
  *    [1]
  *    [2]
  *
  *  +n+ = 2:
+ *
  *    a.repeated_permutation(2) {|permutation| p permutation }
+ *
  *  Output:
+ *
  *    [0, 0]
  *    [0, 1]
  *    [0, 2]
@@ -7027,14 +7399,17 @@ rb_ary_repeated_permutation_size(VALUE ary, VALUE args, VALUE eobj)
  *  If +n+ is zero, calls the block once with an empty \Array.
  *
  *  If +n+ is negative, does not call the block:
+ *
  *    a.repeated_permutation(-1) {|permutation| fail 'Cannot happen' }
  *
  *  Returns a new \Enumerator if no block given:
+ *
  *    a = [0, 1, 2]
  *    a.repeated_permutation(2) # => #<Enumerator: [0, 1, 2]:permutation(2)>
  *
  *  Using Enumerators, it's convenient to show the permutations and counts
  *  for some values of +n+:
+ *
  *    e = a.repeated_permutation(0)
  *    e.size # => 1
  *    e.to_a # => [[]]
@@ -7044,6 +7419,7 @@ rb_ary_repeated_permutation_size(VALUE ary, VALUE args, VALUE eobj)
  *    e = a.repeated_permutation(2)
  *    e.size # => 9
  *    e.to_a # => [[0, 0], [0, 1], [0, 2], [1, 0], [1, 1], [1, 2], [2, 0], [2, 1], [2, 2]]
+ *
  */
 static VALUE
 rb_ary_repeated_permutation(VALUE ary, VALUE num)
@@ -7055,25 +7431,25 @@ rb_ary_repeated_permutation(VALUE ary, VALUE num)
     r = NUM2LONG(num);                    /* Permutation size from argument */
 
     if (r < 0) {
-	/* no permutations: yield nothing */
+        /* no permutations: yield nothing */
     }
     else if (r == 0) { /* exactly one permutation: the zero-length array */
-	rb_yield(rb_ary_new2(0));
+        rb_yield(rb_ary_new2(0));
     }
     else if (r == 1) { /* this is a special, easy case */
-	for (i = 0; i < RARRAY_LEN(ary); i++) {
-	    rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
-	}
+        for (i = 0; i < RARRAY_LEN(ary); i++) {
+            rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
+        }
     }
     else {             /* this is the general case */
-	volatile VALUE t0;
-	long *p = ALLOCV_N(long, t0, r);
-	VALUE ary0 = ary_make_shared_copy(ary); /* private defensive copy of ary */
-	RBASIC_CLEAR_CLASS(ary0);
+        volatile VALUE t0;
+        long *p = ALLOCV_N(long, t0, r);
+        VALUE ary0 = ary_make_shared_copy(ary); /* private defensive copy of ary */
+        RBASIC_CLEAR_CLASS(ary0);
 
-	rpermute0(n, r, p, ary0); /* compute and yield repeated permutations */
-	ALLOCV_END(t0);
-	RBASIC_SET_CLASS_RAW(ary0, rb_cArray);
+        rpermute0(n, r, p, ary0); /* compute and yield repeated permutations */
+        ALLOCV_END(t0);
+        RBASIC_SET_CLASS_RAW(ary0, rb_cArray);
     }
     return ary;
 }
@@ -7085,19 +7461,19 @@ rcombinate0(const long n, const long r, long *const p, const long rest, const VA
 
     p[index] = i;
     for (;;) {
-	if (++index < r-1) {
-	    p[index] = i;
-	    continue;
-	}
-	for (; i < n; ++i) {
-	    p[index] = i;
-	    if (!yield_indexed_values(values, r, p)) {
-		rb_raise(rb_eRuntimeError, "repeated combination reentered");
-	    }
-	}
-	do {
-	    if (index <= 0) return;
-	} while ((i = ++p[--index]) >= n);
+        if (++index < r-1) {
+            p[index] = i;
+            continue;
+        }
+        for (; i < n; ++i) {
+            p[index] = i;
+            if (!yield_indexed_values(values, r, p)) {
+                rb_raise(rb_eRuntimeError, "repeated combination reentered");
+            }
+        }
+        do {
+            if (index <= 0) return;
+        } while ((i = ++p[--index]) >= n);
     }
 }
 
@@ -7107,7 +7483,7 @@ rb_ary_repeated_combination_size(VALUE ary, VALUE args, VALUE eobj)
     long n = RARRAY_LEN(ary);
     long k = NUM2LONG(RARRAY_AREF(args, 0));
     if (k == 0) {
-	return LONG2FIX(1);
+        return LONG2FIX(1);
     }
     return binomial_coefficient(k, n + k - 1);
 }
@@ -7126,16 +7502,22 @@ rb_ary_repeated_combination_size(VALUE ary, VALUE args, VALUE eobj)
  *  The number of combinations is <tt>(n+1)(n+2)/2</tt>.
  *
  *  +n+ = 1:
+ *
  *    a = [0, 1, 2]
  *    a.repeated_combination(1) {|combination| p combination }
+ *
  *  Output:
+ *
  *    [0]
  *    [1]
  *    [2]
  *
  *  +n+ = 2:
+ *
  *    a.repeated_combination(2) {|combination| p combination }
+ *
  *  Output:
+ *
  *    [0, 0]
  *    [0, 1]
  *    [0, 2]
@@ -7146,14 +7528,17 @@ rb_ary_repeated_combination_size(VALUE ary, VALUE args, VALUE eobj)
  *  If +n+ is zero, calls the block once with an empty \Array.
  *
  *  If +n+ is negative, does not call the block:
+ *
  *    a.repeated_combination(-1) {|combination| fail 'Cannot happen' }
  *
  *  Returns a new \Enumerator if no block given:
+ *
  *    a = [0, 1, 2]
  *    a.repeated_combination(2) # => #<Enumerator: [0, 1, 2]:combination(2)>
  *
  *  Using Enumerators, it's convenient to show the combinations and counts
  *  for some values of +n+:
+ *
  *    e = a.repeated_combination(0)
  *    e.size # => 1
  *    e.to_a # => [[]]
@@ -7163,6 +7548,7 @@ rb_ary_repeated_combination_size(VALUE ary, VALUE args, VALUE eobj)
  *    e = a.repeated_combination(2)
  *    e.size # => 6
  *    e.to_a # => [[0, 0], [0, 1], [0, 2], [1, 1], [1, 2], [2, 2]]
+ *
  */
 
 static VALUE
@@ -7174,28 +7560,28 @@ rb_ary_repeated_combination(VALUE ary, VALUE num)
     RETURN_SIZED_ENUMERATOR(ary, 1, &num, rb_ary_repeated_combination_size);   /* Return enumerator if no block */
     len = RARRAY_LEN(ary);
     if (n < 0) {
-	/* yield nothing */
+        /* yield nothing */
     }
     else if (n == 0) {
-	rb_yield(rb_ary_new2(0));
+        rb_yield(rb_ary_new2(0));
     }
     else if (n == 1) {
-	for (i = 0; i < RARRAY_LEN(ary); i++) {
-	    rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
-	}
+        for (i = 0; i < RARRAY_LEN(ary); i++) {
+            rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
+        }
     }
     else if (len == 0) {
-	/* yield nothing */
+        /* yield nothing */
     }
     else {
-	volatile VALUE t0;
-	long *p = ALLOCV_N(long, t0, n);
-	VALUE ary0 = ary_make_shared_copy(ary); /* private defensive copy of ary */
-	RBASIC_CLEAR_CLASS(ary0);
+        volatile VALUE t0;
+        long *p = ALLOCV_N(long, t0, n);
+        VALUE ary0 = ary_make_shared_copy(ary); /* private defensive copy of ary */
+        RBASIC_CLEAR_CLASS(ary0);
 
-	rcombinate0(len, n, p, n, ary0); /* compute and yield repeated combinations */
-	ALLOCV_END(t0);
-	RBASIC_SET_CLASS_RAW(ary0, rb_cArray);
+        rcombinate0(len, n, p, n, ary0); /* compute and yield repeated combinations */
+        ALLOCV_END(t0);
+        RBASIC_SET_CLASS_RAW(ary0, rb_cArray);
     }
     return ary;
 }
@@ -7206,12 +7592,14 @@ rb_ary_repeated_combination(VALUE ary, VALUE num)
  *    array.product(*other_arrays) {|combination| ... } -> self
  *
  *  Computes and returns or yields all combinations of elements from all the Arrays,
- *  including both +self+ and +other_arrays+.
+ *  including both +self+ and +other_arrays+:
+ *
  *  - The number of combinations is the product of the sizes of all the arrays,
  *    including both +self+ and +other_arrays+.
  *  - The order of the returned combinations is indeterminate.
  *
  *  When no block is given, returns the combinations as an \Array of Arrays:
+ *
  *    a = [0, 1, 2]
  *    a1 = [3, 4]
  *    a2 = [5, 6]
@@ -7226,11 +7614,15 @@ rb_ary_repeated_combination(VALUE ary, VALUE num)
  *
  *  If no argument is given, returns an \Array of 1-element Arrays,
  *  each containing an element of +self+:
+ *
  *    a.product # => [[0], [1], [2]]
  *
  *  When a block is given, yields each combination as an \Array; returns +self+:
+ *
  *    a.product(a1) {|combination| p combination }
+ *
  *  Output:
+ *
  *    [0, 3]
  *    [0, 4]
  *    [1, 3]
@@ -7239,21 +7631,26 @@ rb_ary_repeated_combination(VALUE ary, VALUE num)
  *    [2, 4]
  *
  *  If any argument is an empty \Array, does not call the block:
+ *
  *    a.product(a1, a2, []) {|combination| fail 'Cannot happen' }
  *
  *  If no argument is given, yields each element of +self+ as a 1-element \Array:
+ *
  *    a.product {|combination| p combination }
+ *
  *  Output:
+ *
  *    [0]
  *    [1]
  *    [2]
+ *
  */
 
 static VALUE
 rb_ary_product(int argc, VALUE *argv, VALUE ary)
 {
     int n = argc+1;    /* How many arrays we're operating on */
-    volatile VALUE t0 = tmpary(n);
+    volatile VALUE t0 = rb_ary_hidden_new(n);
     volatile VALUE t1 = Qundef;
     VALUE *arrays = RARRAY_PTR(t0); /* The arrays we're computing the product of */
     int *counters = ALLOCV_N(int, t1, n); /* The current position in each one */
@@ -7274,64 +7671,64 @@ rb_ary_product(int argc, VALUE *argv, VALUE ary)
 
     /* Otherwise, allocate and fill in an array of results */
     if (rb_block_given_p()) {
-	/* Make defensive copies of arrays; exit if any is empty */
-	for (i = 0; i < n; i++) {
-	    if (RARRAY_LEN(arrays[i]) == 0) goto done;
-	    arrays[i] = ary_make_shared_copy(arrays[i]);
-	}
+        /* Make defensive copies of arrays; exit if any is empty */
+        for (i = 0; i < n; i++) {
+            if (RARRAY_LEN(arrays[i]) == 0) goto done;
+            arrays[i] = ary_make_shared_copy(arrays[i]);
+        }
     }
     else {
-	/* Compute the length of the result array; return [] if any is empty */
-	for (i = 0; i < n; i++) {
-	    long k = RARRAY_LEN(arrays[i]);
-	    if (k == 0) {
-		result = rb_ary_new2(0);
-		goto done;
-	    }
+        /* Compute the length of the result array; return [] if any is empty */
+        for (i = 0; i < n; i++) {
+            long k = RARRAY_LEN(arrays[i]);
+            if (k == 0) {
+                result = rb_ary_new2(0);
+                goto done;
+            }
             if (MUL_OVERFLOW_LONG_P(resultlen, k))
-		rb_raise(rb_eRangeError, "too big to product");
-	    resultlen *= k;
-	}
-	result = rb_ary_new2(resultlen);
+                rb_raise(rb_eRangeError, "too big to product");
+            resultlen *= k;
+        }
+        result = rb_ary_new2(resultlen);
     }
     for (;;) {
-	int m;
-	/* fill in one subarray */
-	VALUE subarray = rb_ary_new2(n);
-	for (j = 0; j < n; j++) {
-	    rb_ary_push(subarray, rb_ary_entry(arrays[j], counters[j]));
-	}
-
-	/* put it on the result array */
-	if (NIL_P(result)) {
+        int m;
+        /* fill in one subarray */
+        VALUE subarray = rb_ary_new2(n);
+        for (j = 0; j < n; j++) {
+            rb_ary_push(subarray, rb_ary_entry(arrays[j], counters[j]));
+        }
+
+        /* put it on the result array */
+        if (NIL_P(result)) {
             FL_SET(t0, RARRAY_SHARED_ROOT_FLAG);
-	    rb_yield(subarray);
+            rb_yield(subarray);
             if (!FL_TEST(t0, RARRAY_SHARED_ROOT_FLAG)) {
-		rb_raise(rb_eRuntimeError, "product reentered");
-	    }
-	    else {
+                rb_raise(rb_eRuntimeError, "product reentered");
+            }
+            else {
                 FL_UNSET(t0, RARRAY_SHARED_ROOT_FLAG);
-	    }
-	}
-	else {
-	    rb_ary_push(result, subarray);
-	}
-
-	/*
-	 * Increment the last counter.  If it overflows, reset to 0
-	 * and increment the one before it.
-	 */
-	m = n-1;
-	counters[m]++;
-	while (counters[m] == RARRAY_LEN(arrays[m])) {
-	    counters[m] = 0;
-	    /* If the first counter overflows, we are done */
-	    if (--m < 0) goto done;
-	    counters[m]++;
-	}
+            }
+        }
+        else {
+            rb_ary_push(result, subarray);
+        }
+
+        /*
+         * Increment the last counter.  If it overflows, reset to 0
+         * and increment the one before it.
+         */
+        m = n-1;
+        counters[m]++;
+        while (counters[m] == RARRAY_LEN(arrays[m])) {
+            counters[m] = 0;
+            /* If the first counter overflows, we are done */
+            if (--m < 0) goto done;
+            counters[m]++;
+        }
     }
+
 done:
-    tmpary_discard(t0);
     ALLOCV_END(t1);
 
     return NIL_P(result) ? ary : result;
@@ -7346,11 +7743,13 @@ done:
  *  does not modify +self+.
  *
  *  Examples:
+ *
  *    a = [0, 1, 2, 3, 4, 5]
  *    a.take(1) # => [0]
  *    a.take(2) # => [0, 1]
  *    a.take(50) # => [0, 1, 2, 3, 4, 5]
  *    a # => [0, 1, 2, 3, 4, 5]
+ *
  */
 
 static VALUE
@@ -7358,7 +7757,7 @@ rb_ary_take(VALUE obj, VALUE n)
 {
     long len = NUM2LONG(n);
     if (len < 0) {
-	rb_raise(rb_eArgError, "attempt to take negative size");
+        rb_raise(rb_eArgError, "attempt to take negative size");
     }
     return rb_ary_subseq(obj, 0, len);
 }
@@ -7374,13 +7773,16 @@ rb_ary_take(VALUE obj, VALUE n)
  *  With a block given, calls the block with each successive element of +self+;
  *  stops if the block returns +false+ or +nil+;
  *  returns a new \Array containing those elements for which the block returned a truthy value:
+ *
  *    a = [0, 1, 2, 3, 4, 5]
  *    a.take_while {|element| element < 3 } # => [0, 1, 2]
  *    a.take_while {|element| true } # => [0, 1, 2, 3, 4, 5]
  *    a # => [0, 1, 2, 3, 4, 5]
  *
  *  With no block given, returns a new \Enumerator:
+ *
  *    [0, 1].take_while # => #<Enumerator: [0, 1]:take_while>
+ *
  */
 
 static VALUE
@@ -7390,7 +7792,7 @@ rb_ary_take_while(VALUE ary)
 
     RETURN_ENUMERATOR(ary, 0, 0);
     for (i = 0; i < RARRAY_LEN(ary); i++) {
-	if (!RTEST(rb_yield(RARRAY_AREF(ary, i)))) break;
+        if (!RTEST(rb_yield(RARRAY_AREF(ary, i)))) break;
     }
     return rb_ary_take(ary, LONG2FIX(i));
 }
@@ -7404,10 +7806,12 @@ rb_ary_take_while(VALUE ary)
  *  does not modify +self+.
  *
  *  Examples:
+ *
  *    a = [0, 1, 2, 3, 4, 5]
  *    a.drop(0) # => [0, 1, 2, 3, 4, 5]
  *    a.drop(1) # => [1, 2, 3, 4, 5]
  *    a.drop(2) # => [2, 3, 4, 5]
+ *
  */
 
 static VALUE
@@ -7416,7 +7820,7 @@ rb_ary_drop(VALUE ary, VALUE n)
     VALUE result;
     long pos = NUM2LONG(n);
     if (pos < 0) {
-	rb_raise(rb_eArgError, "attempt to drop negative size");
+        rb_raise(rb_eArgError, "attempt to drop negative size");
     }
 
     result = rb_ary_subseq(ary, pos, RARRAY_LEN(ary));
@@ -7435,11 +7839,14 @@ rb_ary_drop(VALUE ary, VALUE n)
  *  With a block given, calls the block with each successive element of +self+;
  *  stops if the block returns +false+ or +nil+;
  *  returns a new \Array _omitting_ those elements for which the block returned a truthy value:
+ *
  *    a = [0, 1, 2, 3, 4, 5]
  *    a.drop_while {|element| element < 3 } # => [3, 4, 5]
  *
  *  With no block given, returns a new \Enumerator:
+ *
  *    [0, 1].drop_while # => # => #<Enumerator: [0, 1]:drop_while>
+ *
  */
 
 static VALUE
@@ -7449,7 +7856,7 @@ rb_ary_drop_while(VALUE ary)
 
     RETURN_ENUMERATOR(ary, 0, 0);
     for (i = 0; i < RARRAY_LEN(ary); i++) {
-	if (!RTEST(rb_yield(RARRAY_AREF(ary, i)))) break;
+        if (!RTEST(rb_yield(RARRAY_AREF(ary, i)))) break;
     }
     return rb_ary_drop(ary, LONG2FIX(i));
 }
@@ -7464,17 +7871,20 @@ rb_ary_drop_while(VALUE ary)
  *
  *  With no block given and no argument, returns +true+ if +self+ has any truthy element,
  *  +false+ otherwise:
+ *
  *    [nil, 0, false].any? # => true
  *    [nil, false].any? # => false
  *    [].any? # => false
  *
  *  With a block given and no argument, calls the block with each element in +self+;
  *  returns +true+ if the block returns any truthy value, +false+ otherwise:
+ *
  *    [0, 1, 2].any? {|element| element > 1 } # => true
  *    [0, 1, 2].any? {|element| element > 2 } # => false
  *
  *  If argument +obj+ is given, returns +true+ if +obj+.<tt>===</tt> any element,
  *  +false+ otherwise:
+ *
  *    ['food', 'drink'].any?(/foo/) # => true
  *    ['food', 'drink'].any?(/bar/) # => false
  *    [].any?(/foo/) # => false
@@ -7495,9 +7905,9 @@ rb_ary_any_p(int argc, VALUE *argv, VALUE ary)
         if (rb_block_given_p()) {
             rb_warn("given block not used");
         }
-	for (i = 0; i < RARRAY_LEN(ary); ++i) {
-	    if (RTEST(rb_funcall(argv[0], idEqq, 1, RARRAY_AREF(ary, i)))) return Qtrue;
-	}
+        for (i = 0; i < RARRAY_LEN(ary); ++i) {
+            if (RTEST(rb_funcall(argv[0], idEqq, 1, RARRAY_AREF(ary, i)))) return Qtrue;
+        }
     }
     else if (!rb_block_given_p()) {
         for (i = 0; i < len; ++i) {
@@ -7505,9 +7915,9 @@ rb_ary_any_p(int argc, VALUE *argv, VALUE ary)
         }
     }
     else {
-	for (i = 0; i < RARRAY_LEN(ary); ++i) {
-	    if (RTEST(rb_yield(RARRAY_AREF(ary, i)))) return Qtrue;
-	}
+        for (i = 0; i < RARRAY_LEN(ary); ++i) {
+            if (RTEST(rb_yield(RARRAY_AREF(ary, i)))) return Qtrue;
+        }
     }
     return Qfalse;
 }
@@ -7522,16 +7932,19 @@ rb_ary_any_p(int argc, VALUE *argv, VALUE ary)
  *
  *  With no block given and no argument, returns +true+ if +self+ contains only truthy elements,
  *  +false+ otherwise:
+ *
  *    [0, 1, :foo].all? # => true
  *    [0, nil, 2].all? # => false
  *    [].all? # => true
  *
  *  With a block given and no argument, calls the block with each element in +self+;
  *  returns +true+ if the block returns only truthy values, +false+ otherwise:
+ *
  *    [0, 1, 2].all? { |element| element < 3 } # => true
  *    [0, 1, 2].all? { |element| element < 2 } # => false
  *
  *  If argument +obj+ is given, returns +true+ if <tt>obj.===</tt> every element, +false+ otherwise:
+ *
  *    ['food', 'fool', 'foot'].all?(/foo/) # => true
  *    ['food', 'drink'].all?(/bar/) # => false
  *    [].all?(/foo/) # => true
@@ -7579,16 +7992,19 @@ rb_ary_all_p(int argc, VALUE *argv, VALUE ary)
  *
  *  With no block given and no argument, returns +true+ if +self+ has no truthy elements,
  *  +false+ otherwise:
+ *
  *    [nil, false].none? # => true
  *    [nil, 0, false].none? # => false
  *    [].none? # => true
  *
  *  With a block given and no argument, calls the block with each element in +self+;
  *  returns +true+ if the block returns no truthy value, +false+ otherwise:
+ *
  *    [0, 1, 2].none? {|element| element > 3 } # => true
  *    [0, 1, 2].none? {|element| element > 1 } # => false
  *
  *  If argument +obj+ is given, returns +true+ if <tt>obj.===</tt> no element, +false+ otherwise:
+ *
  *    ['food', 'drink'].none?(/bar/) # => true
  *    ['food', 'drink'].none?(/foo/) # => false
  *    [].none?(/foo/) # => true
@@ -7636,6 +8052,7 @@ rb_ary_none_p(int argc, VALUE *argv, VALUE ary)
  *
  *  With no block given and no argument, returns +true+ if +self+ has exactly one truthy element,
  *  +false+ otherwise:
+ *
  *    [nil, 0].one? # => true
  *    [0, 0].one? # => false
  *    [nil, nil].one? # => false
@@ -7643,12 +8060,14 @@ rb_ary_none_p(int argc, VALUE *argv, VALUE ary)
  *
  *  With a block given and no argument, calls the block with each element in +self+;
  *  returns +true+ if the block a truthy value for exactly one element, +false+ otherwise:
+ *
  *    [0, 1, 2].one? {|element| element > 0 } # => false
  *    [0, 1, 2].one? {|element| element > 1 } # => true
  *    [0, 1, 2].one? {|element| element > 2 } # => false
  *
  *  If argument +obj+ is given, returns +true+ if <tt>obj.===</tt> exactly one element,
  *  +false+ otherwise:
+ *
  *    [0, 1, 2].one?(0) # => true
  *    [0, 0, 1].one?(0) # => false
  *    [1, 1, 2].one?(0) # => false
@@ -7707,11 +8126,13 @@ rb_ary_one_p(int argc, VALUE *argv, VALUE ary)
  *  See {Dig Methods}[rdoc-ref:dig_methods.rdoc].
  *
  *  Examples:
+ *
  *    a = [:foo, [:bar, :baz, [:bat, :bam]]]
  *    a.dig(1) # => [:bar, :baz, [:bat, :bam]]
  *    a.dig(1, 2) # => [:bat, :bam]
  *    a.dig(1, 2, 0) # => :bat
  *    a.dig(1, 2, 3) # => nil
+ *
  */
 
 static VALUE
@@ -7729,7 +8150,7 @@ finish_exact_sum(long n, VALUE r, VALUE v, int z)
 {
     if (n != 0)
         v = rb_fix_plus(LONG2FIX(n), v);
-    if (r != Qundef) {
+    if (!UNDEF_P(r)) {
         v = rb_rational_plus(r, v);
     }
     else if (!n && z) {
@@ -7744,31 +8165,38 @@ finish_exact_sum(long n, VALUE r, VALUE v, int z)
  *   array.sum(init = 0) {|element| ... } -> object
  *
  *  When no block is given, returns the object equivalent to:
+ *
  *    sum = init
  *    array.each {|element| sum += element }
  *    sum
+ *
  *  For example, <tt>[e1, e2, e3].sum</tt> returns <tt>init + e1 + e2 + e3</tt>.
  *
  *  Examples:
+ *
  *    a = [0, 1, 2, 3]
  *    a.sum # => 6
  *    a.sum(100) # => 106
  *
  *  The elements need not be numeric, but must be <tt>+</tt>-compatible
  *  with each other and with +init+:
+ *
  *    a = ['abc', 'def', 'ghi']
  *    a.sum('jkl') # => "jklabcdefghi"
  *
  *  When a block is given, it is called with each element
  *  and the block's return value (instead of the element itself) is used as the addend:
+ *
  *    a = ['zero', 1, :two]
  *    s = a.sum('Coerced and concatenated: ') {|element| element.to_s }
  *    s # => "Coerced and concatenated: zero1two"
  *
  *  Notes:
+ *
  *  - Array#join and Array#flatten may be faster than Array#sum
  *    for an \Array of Strings or an \Array of Arrays.
  *  - Array#sum method may not respect method redefinition of "+" methods such as Integer#+.
+ *
  */
 
 static VALUE
@@ -7801,7 +8229,7 @@ rb_ary_sum(int argc, VALUE *argv, VALUE ary)
         else if (RB_BIGNUM_TYPE_P(e))
             v = rb_big_plus(e, v);
         else if (RB_TYPE_P(e, T_RATIONAL)) {
-            if (r == Qundef)
+            if (UNDEF_P(r))
                 r = e;
             else
                 r = rb_rational_plus(r, e);
@@ -8311,7 +8739,7 @@ rb_ary_deconstruct(VALUE ary)
  *
  *  - #pop: Removes and returns the last element.
  *  - #shift:  Removes and returns the first element.
- *  - #compact!: Removes all non-+nil+ elements.
+ *  - #compact!: Removes all +nil+ elements.
  *  - #delete: Removes elements equal to a given object.
  *  - #delete_at: Removes the element at a given offset.
  *  - #delete_if: Removes elements specified by a given block.
diff --git a/ast.c b/ast.c
index 42d4126a5b..adb7287ed3 100644
--- a/ast.c
+++ b/ast.c
@@ -64,8 +64,8 @@ ast_new_internal(rb_ast_t *ast, const NODE *node)
     return obj;
 }
 
-static VALUE rb_ast_parse_str(VALUE str, VALUE keep_script_lines);
-static VALUE rb_ast_parse_file(VALUE path, VALUE keep_script_lines);
+static VALUE rb_ast_parse_str(VALUE str, VALUE keep_script_lines, VALUE error_tolerant, VALUE keep_tokens);
+static VALUE rb_ast_parse_file(VALUE path, VALUE keep_script_lines, VALUE error_tolerant, VALUE keep_tokens);
 
 static VALUE
 ast_parse_new(void)
@@ -85,31 +85,33 @@ ast_parse_done(rb_ast_t *ast)
 }
 
 static VALUE
-ast_s_parse(rb_execution_context_t *ec, VALUE module, VALUE str, VALUE keep_script_lines)
+ast_s_parse(rb_execution_context_t *ec, VALUE module, VALUE str, VALUE keep_script_lines, VALUE error_tolerant, VALUE keep_tokens)
 {
-    return rb_ast_parse_str(str, keep_script_lines);
+    return rb_ast_parse_str(str, keep_script_lines, error_tolerant, keep_tokens);
 }
 
 static VALUE
-rb_ast_parse_str(VALUE str, VALUE keep_script_lines)
+rb_ast_parse_str(VALUE str, VALUE keep_script_lines, VALUE error_tolerant, VALUE keep_tokens)
 {
     rb_ast_t *ast = 0;
 
     StringValue(str);
     VALUE vparser = ast_parse_new();
     if (RTEST(keep_script_lines)) rb_parser_keep_script_lines(vparser);
+    if (RTEST(error_tolerant)) rb_parser_error_tolerant(vparser);
+    if (RTEST(keep_tokens)) rb_parser_keep_tokens(vparser);
     ast = rb_parser_compile_string_path(vparser, Qnil, str, 1);
     return ast_parse_done(ast);
 }
 
 static VALUE
-ast_s_parse_file(rb_execution_context_t *ec, VALUE module, VALUE path, VALUE keep_script_lines)
+ast_s_parse_file(rb_execution_context_t *ec, VALUE module, VALUE path, VALUE keep_script_lines, VALUE error_tolerant, VALUE keep_tokens)
 {
-    return rb_ast_parse_file(path, keep_script_lines);
+    return rb_ast_parse_file(path, keep_script_lines, error_tolerant, keep_tokens);
 }
 
 static VALUE
-rb_ast_parse_file(VALUE path, VALUE keep_script_lines)
+rb_ast_parse_file(VALUE path, VALUE keep_script_lines, VALUE error_tolerant, VALUE keep_tokens)
 {
     VALUE f;
     rb_ast_t *ast = 0;
@@ -120,6 +122,8 @@ rb_ast_parse_file(VALUE path, VALUE keep_script_lines)
     rb_funcall(f, rb_intern("set_encoding"), 2, rb_enc_from_encoding(enc), rb_str_new_cstr("-"));
     VALUE vparser = ast_parse_new();
     if (RTEST(keep_script_lines)) rb_parser_keep_script_lines(vparser);
+    if (RTEST(error_tolerant))  rb_parser_error_tolerant(vparser);
+    if (RTEST(keep_tokens))  rb_parser_keep_tokens(vparser);
     ast = rb_parser_compile_file_path(vparser, Qnil, f, 1);
     rb_io_close(f);
     return ast_parse_done(ast);
@@ -139,13 +143,15 @@ lex_array(VALUE array, int index)
 }
 
 static VALUE
-rb_ast_parse_array(VALUE array, VALUE keep_script_lines)
+rb_ast_parse_array(VALUE array, VALUE keep_script_lines, VALUE error_tolerant, VALUE keep_tokens)
 {
     rb_ast_t *ast = 0;
 
     array = rb_check_array_type(array);
     VALUE vparser = ast_parse_new();
     if (RTEST(keep_script_lines)) rb_parser_keep_script_lines(vparser);
+    if (RTEST(error_tolerant)) rb_parser_error_tolerant(vparser);
+    if (RTEST(keep_tokens)) rb_parser_keep_tokens(vparser);
     ast = rb_parser_compile_generic(vparser, lex_array, Qnil, array, 1);
     return ast_parse_done(ast);
 }
@@ -193,7 +199,24 @@ script_lines(VALUE path)
 }
 
 static VALUE
-ast_s_of(rb_execution_context_t *ec, VALUE module, VALUE body, VALUE keep_script_lines)
+node_id_for_backtrace_location(rb_execution_context_t *ec, VALUE module, VALUE location)
+{
+    int node_id;
+
+    if (!rb_frame_info_p(location)) {
+        rb_raise(rb_eTypeError, "Thread::Backtrace::Location object expected");
+    }
+
+    node_id = rb_get_node_id_from_frame_info(location);
+    if (node_id == -1) {
+        return Qnil;
+    }
+
+    return INT2NUM(node_id);
+}
+
+static VALUE
+ast_s_of(rb_execution_context_t *ec, VALUE module, VALUE body, VALUE keep_script_lines, VALUE error_tolerant, VALUE keep_tokens)
 {
     VALUE node, lines = Qnil;
     const rb_iseq_t *iseq;
@@ -232,13 +255,13 @@ ast_s_of(rb_execution_context_t *ec, VALUE module, VALUE body, VALUE keep_script
     }
 
     if (!NIL_P(lines) || !NIL_P(lines = script_lines(path))) {
-        node = rb_ast_parse_array(lines, keep_script_lines);
+        node = rb_ast_parse_array(lines, keep_script_lines, error_tolerant, keep_tokens);
     }
     else if (e_option) {
-        node = rb_ast_parse_str(rb_e_script, keep_script_lines);
+        node = rb_ast_parse_str(rb_e_script, keep_script_lines, error_tolerant, keep_tokens);
     }
     else {
-        node = rb_ast_parse_file(path, keep_script_lines);
+        node = rb_ast_parse_file(path, keep_script_lines, error_tolerant, keep_tokens);
     }
 
     return node_find(node, node_id);
@@ -645,6 +668,8 @@ node_children(rb_ast_t *ast, const NODE *node)
                                         NEW_CHILD(ast, node->nd_pkwargs),
                                         kwrest);
         }
+      case NODE_ERROR:
+        return rb_ary_new_from_node_args(ast, 0);
       case NODE_ARGS_AUX:
       case NODE_LAST:
         break;
@@ -699,6 +724,15 @@ ast_node_last_column(rb_execution_context_t *ec, VALUE self)
 }
 
 static VALUE
+ast_node_all_tokens(rb_execution_context_t *ec, VALUE self)
+{
+    struct ASTNodeData *data;
+    TypedData_Get_Struct(self, struct ASTNodeData, &rb_node_type, data);
+
+    return rb_ast_tokens(data->ast);
+}
+
+static VALUE
 ast_node_inspect(rb_execution_context_t *ec, VALUE self)
 {
     VALUE str;
diff --git a/ast.rb b/ast.rb
index f866bd23e5..f3f72c747f 100644
--- a/ast.rb
+++ b/ast.rb
@@ -20,21 +20,47 @@
 module RubyVM::AbstractSyntaxTree
 
   #  call-seq:
-  #     RubyVM::AbstractSyntaxTree.parse(string) -> RubyVM::AbstractSyntaxTree::Node
+  #     RubyVM::AbstractSyntaxTree.parse(string, keep_script_lines: false, error_tolerant: false, keep_tokens: false) -> RubyVM::AbstractSyntaxTree::Node
   #
   #  Parses the given _string_ into an abstract syntax tree,
   #  returning the root node of that tree.
   #
-  #  SyntaxError is raised if the given _string_ is invalid syntax.
-  #
   #    RubyVM::AbstractSyntaxTree.parse("x = 1 + 2")
   #    # => #<RubyVM::AbstractSyntaxTree::Node:SCOPE@1:0-1:9>
-  def self.parse string, keep_script_lines: false
-    Primitive.ast_s_parse string, keep_script_lines
+  #
+  #  If <tt>keep_script_lines: true</tt> option is provided, the text of the parsed
+  #  source is associated with nodes and is available via Node#script_lines.
+  #
+  #  If <tt>keep_tokens: true</tt> option is provided, Node#tokens are populated.
+  #
+  #  SyntaxError is raised if the given _string_ is invalid syntax. To overwrite this
+  #  behavior, <tt>error_tolerant: true</tt> can be provided. In this case, the parser
+  #  will produce a tree where expressions with syntax errors would be represented by
+  #  Node with <tt>type=:ERROR</tt>.
+  #
+  #     root = RubyVM::AbstractSyntaxTree.parse("x = 1; p(x; y=2")
+  #     # <internal:ast>:33:in `parse': syntax error, unexpected ';', expecting ')' (SyntaxError)
+  #     # x = 1; p(x; y=2
+  #     #           ^
+  #
+  #     root = RubyVM::AbstractSyntaxTree.parse("x = 1; p(x; y=2", error_tolerant: true)
+  #     # (SCOPE@1:0-1:15
+  #     #  tbl: [:x, :y]
+  #     #  args: nil
+  #     #  body: (BLOCK@1:0-1:15 (LASGN@1:0-1:5 :x (LIT@1:4-1:5 1)) (ERROR@1:7-1:11) (LASGN@1:12-1:15 :y (LIT@1:14-1:15 2))))
+  #     root.children.last.children
+  #     # [(LASGN@1:0-1:5 :x (LIT@1:4-1:5 1)),
+  #     #  (ERROR@1:7-1:11),
+  #     #  (LASGN@1:12-1:15 :y (LIT@1:14-1:15 2))]
+  #
+  #  Note that parsing continues even after the errored expresion.
+  #
+  def self.parse string, keep_script_lines: false, error_tolerant: false, keep_tokens: false
+    Primitive.ast_s_parse string, keep_script_lines, error_tolerant, keep_tokens
   end
 
   #  call-seq:
-  #     RubyVM::AbstractSyntaxTree.parse_file(pathname) -> RubyVM::AbstractSyntaxTree::Node
+  #     RubyVM::AbstractSyntaxTree.parse_file(pathname, keep_script_lines: false, error_tolerant: false, keep_tokens: false) -> RubyVM::AbstractSyntaxTree::Node
   #
   #   Reads the file from _pathname_, then parses it like ::parse,
   #   returning the root node of the abstract syntax tree.
@@ -44,13 +70,15 @@ module RubyVM::AbstractSyntaxTree
   #
   #     RubyVM::AbstractSyntaxTree.parse_file("my-app/app.rb")
   #     # => #<RubyVM::AbstractSyntaxTree::Node:SCOPE@1:0-31:3>
-  def self.parse_file pathname, keep_script_lines: false
-    Primitive.ast_s_parse_file pathname, keep_script_lines
+  #
+  #   See ::parse for explanation of keyword argument meaning and usage.
+  def self.parse_file pathname, keep_script_lines: false, error_tolerant: false, keep_tokens: false
+    Primitive.ast_s_parse_file pathname, keep_script_lines, error_tolerant, keep_tokens
   end
 
   #  call-seq:
-  #     RubyVM::AbstractSyntaxTree.of(proc)   -> RubyVM::AbstractSyntaxTree::Node
-  #     RubyVM::AbstractSyntaxTree.of(method) -> RubyVM::AbstractSyntaxTree::Node
+  #     RubyVM::AbstractSyntaxTree.of(proc, keep_script_lines: false, error_tolerant: false, keep_tokens: false)   -> RubyVM::AbstractSyntaxTree::Node
+  #     RubyVM::AbstractSyntaxTree.of(method, keep_script_lines: false, error_tolerant: false, keep_tokens: false) -> RubyVM::AbstractSyntaxTree::Node
   #
   #   Returns AST nodes of the given _proc_ or _method_.
   #
@@ -63,8 +91,25 @@ module RubyVM::AbstractSyntaxTree
   #
   #     RubyVM::AbstractSyntaxTree.of(method(:hello))
   #     # => #<RubyVM::AbstractSyntaxTree::Node:SCOPE@1:0-3:3>
-  def self.of body, keep_script_lines: false
-    Primitive.ast_s_of body, keep_script_lines
+  #
+  #   See ::parse for explanation of keyword argument meaning and usage.
+  def self.of body, keep_script_lines: false, error_tolerant: false, keep_tokens: false
+    Primitive.ast_s_of body, keep_script_lines, error_tolerant, keep_tokens
+  end
+
+  #  call-seq:
+  #     RubyVM::AbstractSyntaxTree.node_id_for_backtrace_location(backtrace_location)   -> integer
+  #
+  #   Returns the node id for the given backtrace location.
+  #
+  #     begin
+  #       raise
+  #     rescue =>  e
+  #       loc = e.backtrace_locations.first
+  #       RubyVM::AbstractSyntaxTree.node_id_for_backtrace_location(loc)
+  #     end # => 0
+  def self.node_id_for_backtrace_location backtrace_location
+    Primitive.node_id_for_backtrace_location backtrace_location
   end
 
   # RubyVM::AbstractSyntaxTree::Node instances are created by parse methods in
@@ -122,6 +167,47 @@ module RubyVM::AbstractSyntaxTree
     end
 
     #  call-seq:
+    #     node.tokens -> array
+    #
+    #  Returns tokens corresponding to the location of the node.
+    #  Returns +nil+ if +keep_tokens+ is not enabled when #parse method is called.
+    #
+    #    root = RubyVM::AbstractSyntaxTree.parse("x = 1 + 2", keep_tokens: true)
+    #    root.tokens # => [[0, :tIDENTIFIER, "x", [1, 0, 1, 1]], [1, :tSP, " ", [1, 1, 1, 2]], ...]
+    #    root.tokens.map{_1[2]}.join # => "x = 1 + 2"
+    #
+    #  Token is an array of:
+    #
+    #  - id
+    #  - token type
+    #  - source code text
+    #  - location [ first_lineno, first_column, last_lineno, last_column ]
+    def tokens
+      return nil unless all_tokens
+
+      all_tokens.each_with_object([]) do |token, a|
+        loc = token.last
+        if ([first_lineno, first_column] <=> [loc[0], loc[1]]) <= 0 &&
+           ([last_lineno, last_column]   <=> [loc[2], loc[3]]) >= 0
+           a << token
+        end
+      end
+    end
+
+    #  call-seq:
+    #     node.all_tokens -> array
+    #
+    #  Returns all tokens for the input script regardless the receiver node.
+    #  Returns +nil+ if +keep_tokens+ is not enabled when #parse method is called.
+    #
+    #    root = RubyVM::AbstractSyntaxTree.parse("x = 1 + 2", keep_tokens: true)
+    #    root.all_tokens # => [[0, :tIDENTIFIER, "x", [1, 0, 1, 1]], [1, :tSP, " ", [1, 1, 1, 2]], ...]
+    #    root.children[-1].all_tokens # => [[0, :tIDENTIFIER, "x", [1, 0, 1, 1]], [1, :tSP, " ", [1, 1, 1, 2]], ...]
+    def all_tokens
+      Primitive.ast_node_all_tokens
+    end
+
+    #  call-seq:
     #     node.children -> array
     #
     #  Returns AST nodes under this one.  Each kind of node
diff --git a/benchmark/README.md b/benchmark/README.md
index c222164be3..e11381cad9 100644
--- a/benchmark/README.md
+++ b/benchmark/README.md
@@ -28,16 +28,18 @@ See also:
 
 ```console
 Usage: benchmark-driver [options] RUBY|YAML...
-    -r, --runner TYPE                Specify runner type: ips, time, memory, once (default: ips)
-    -o, --output TYPE                Specify output type: compare, simple, markdown, record (default: compare)
+    -r, --runner TYPE                Specify runner type: ips, time, memory, once, block (default: ips)
+    -o, --output TYPE                Specify output type: compare, simple, markdown, record, all (default: compare)
     -e, --executables EXECS          Ruby executables (e1::path1 arg1; e2::path2 arg2;...)
         --rbenv VERSIONS             Ruby executables in rbenv (x.x.x arg1;y.y.y arg2;...)
         --repeat-count NUM           Try benchmark NUM times and use the fastest result or the worst memory usage
         --repeat-result TYPE         Yield "best", "average" or "worst" result with --repeat-count (default: best)
+        --alternate                  Alternate executables instead of running the same executable in a row with --repeat-count
         --bundler                    Install and use gems specified in Gemfile
         --filter REGEXP              Filter out benchmarks with given regexp
         --run-duration SECONDS       Warmup estimates loop_count to run for this duration (default: 3)
-    -v, --verbose                    Verbose mode. Multiple -v options increase visibility (max: 2)
+        --timeout SECONDS            Timeout ruby command execution with timeout(1)
+    -v, --verbose                    Verbose mode. Multiple -v options increase visilibity (max: 2)
 ```
 
 ## make benchmark
diff --git a/benchmark/array_sort_int.yml b/benchmark/array_sort_int.yml
new file mode 100644
index 0000000000..7b9027ebf7
--- /dev/null
+++ b/benchmark/array_sort_int.yml
@@ -0,0 +1,15 @@
+prelude: |
+  ary2 = 2.times.to_a.shuffle
+  ary10 = 10.times.to_a.shuffle
+  ary100 = 100.times.to_a.shuffle
+  ary1000 = 1000.times.to_a.shuffle
+  ary10000 = 10000.times.to_a.shuffle
+
+benchmark:
+  ary2.sort: ary2.sort
+  ary10.sort: ary10.sort
+  ary100.sort: ary100.sort
+  ary1000.sort: ary1000.sort
+  ary10000.sort: ary10000.sort
+
+loop_count: 10000
diff --git a/benchmark/buffer_each.yml b/benchmark/buffer_each.yml
new file mode 100644
index 0000000000..417941104e
--- /dev/null
+++ b/benchmark/buffer_each.yml
@@ -0,0 +1,27 @@
+prelude: |
+  # frozen_string_literal: true
+  Warning[:experimental] = false
+  string = "The quick brown fox jumped over the lazy dog."
+  array = string.bytes
+  buffer = IO::Buffer.for(string)
+benchmark:
+  string.each_byte: |
+    upcased = String.new
+    string.each_byte do |byte|
+      upcased << (byte ^ 32)
+    end
+  array.each: |
+    upcased = String.new
+    array.each do |byte|
+      upcased << (byte ^ 32)
+    end
+  buffer.each: |
+    upcased = String.new
+    buffer.each(:U8) do |offset, byte|
+      upcased << (byte ^ 32)
+    end
+  buffer.each_byte: |
+    upcased = String.new
+    buffer.each_byte do |byte|
+      upcased << (byte ^ 32)
+    end
diff --git a/benchmark/buffer_get.yml b/benchmark/buffer_get.yml
index e375dcf85d..9e1f99d64e 100644
--- a/benchmark/buffer_get.yml
+++ b/benchmark/buffer_get.yml
@@ -1,9 +1,25 @@
+prelude: |
+  # frozen_string_literal: true
+  Warning[:experimental] = false
+  string = "The quick brown fox jumped over the lazy dog."
+  buffer = IO::Buffer.for(string)
+  format = [:U32, :U32, :U32, :U32]
 benchmark:
-  - name: buffer.get
-    prelude: buffer = IO::Buffer.new(32, IO::Buffer::MAPPED)
-    script: buffer.get(:U32, 0)
-    loop_count: 20000000
-  - name: string.unpack
-    prelude: string = "\0" * 32
-    script: string.unpack("C")
-    loop_count: 20000000
+  string.unpack1: |
+    [
+      string.unpack1("N"),
+      string.unpack1("N", offset: 4),
+      string.unpack1("N", offset: 8),
+      string.unpack1("N", offset: 12),
+    ]
+  buffer.get_value: |
+    [
+      buffer.get_value(:U32, 0),
+      buffer.get_value(:U32, 4),
+      buffer.get_value(:U32, 8),
+      buffer.get_value(:U32, 12),
+    ]
+  buffer.get_values: |
+    buffer.get_values(format, 0)
+  string.unpack: |
+    string.unpack("NNNN")
diff --git a/benchmark/cgi_escape_html.yml b/benchmark/cgi_escape_html.yml
index af6abd08ac..655be9d7d8 100644
--- a/benchmark/cgi_escape_html.yml
+++ b/benchmark/cgi_escape_html.yml
@@ -1,32 +1,23 @@
-prelude: require 'cgi/escape'
+prelude: |
+  # frozen_string_literal: true
+  require 'cgi/escape'
 benchmark:
-  - name: escape_html_blank
-    prelude: str = ""
-    script: CGI.escapeHTML(str)
+  - script: CGI.escapeHTML("")
     loop_count: 20000000
-  - name: escape_html_short_none
-    prelude: str = "abcde"
-    script: CGI.escapeHTML(str)
+  - script: CGI.escapeHTML("abcde")
     loop_count: 20000000
-  - name: escape_html_short_one
-    prelude: str = "abcd<"
-    script: CGI.escapeHTML(str)
+  - script: CGI.escapeHTML("abcd<")
     loop_count: 20000000
-  - name: escape_html_short_all
-    prelude: str = "'&\"<>"
-    script: CGI.escapeHTML(str)
+  - script: CGI.escapeHTML("'&\"<>")
     loop_count: 5000000
-  - name: escape_html_long_none
-    prelude: str = "abcde" * 300
-    script: CGI.escapeHTML(str)
+  - prelude: long_no_escape = "abcde" * 300
+    script: CGI.escapeHTML(long_no_escape)
     loop_count: 1000000
-  - name: escape_html_long_all
-    prelude: str = "'&\"<>" * 10
-    script: CGI.escapeHTML(str)
+  - prelude: long_all_escape = "'&\"<>" * 10
+    script: CGI.escapeHTML(long_all_escape)
     loop_count: 1000000
-  - name: escape_html_real
-    prelude: | # http://example.com/
-      str = <<~HTML
+  - prelude: | # http://example.com/
+      example_html = <<~HTML
         <body>
         <div>
             <h1>Example Domain</h1>
@@ -36,5 +27,5 @@ benchmark:
         </div>
         </body>
       HTML
-    script: CGI.escapeHTML(str)
+    script: CGI.escapeHTML(example_html)
     loop_count: 1000000
diff --git a/benchmark/enum_minmax.yml b/benchmark/enum_minmax.yml
new file mode 100644
index 0000000000..9d01731abb
--- /dev/null
+++ b/benchmark/enum_minmax.yml
@@ -0,0 +1,25 @@
+prelude: |
+  set2 = 2.times.to_a.shuffle.to_set
+  set10 = 10.times.to_a.shuffle.to_set
+  set100 = 100.times.to_a.shuffle.to_set
+  set1000 = 1000.times.to_a.shuffle.to_set
+  set10000 = 10000.times.to_a.shuffle.to_set
+
+benchmark:
+  set2.min: set2.min
+  set10.min: set10.min
+  set100.min: set100.min
+  set1000.min: set1000.min
+  set10000.min: set10000.min
+  set2.max: set2.max
+  set10.max: set10.max
+  set100.max: set100.max
+  set1000.max: set1000.max
+  set10000.max: set10000.max
+  set2.minmax: set2.minmax
+  set10.minmax: set10.minmax
+  set100.minmax: set100.minmax
+  set1000.minmax: set1000.minmax
+  set10000.minmax: set10000.minmax
+
+loop_count: 10000
diff --git a/benchmark/enum_sort.yml b/benchmark/enum_sort.yml
new file mode 100644
index 0000000000..6f26e748c6
--- /dev/null
+++ b/benchmark/enum_sort.yml
@@ -0,0 +1,15 @@
+prelude: |
+  set2 = 2.times.to_a.shuffle.to_set
+  set10 = 10.times.to_a.shuffle.to_set
+  set100 = 100.times.to_a.shuffle.to_set
+  set1000 = 1000.times.to_a.shuffle.to_set
+  set10000 = 10000.times.to_a.shuffle.to_set
+
+benchmark:
+  set2.sort_by: set2.sort_by { 0 }
+  set10.sort_by: set10.sort_by { 0 }
+  set100.sort_by: set100.sort_by { 0 }
+  set1000.sort_by: set1000.sort_by { 0 }
+  set10000.sort_by: set10000.sort_by { 0 }
+
+loop_count: 10000
diff --git a/benchmark/erb_escape_html.yml b/benchmark/erb_escape_html.yml
new file mode 100644
index 0000000000..ca28d756e7
--- /dev/null
+++ b/benchmark/erb_escape_html.yml
@@ -0,0 +1,31 @@
+prelude: |
+  # frozen_string_literal: true
+  require 'erb'
+benchmark:
+  - script: ERB::Util.html_escape("")
+    loop_count: 20000000
+  - script: ERB::Util.html_escape("abcde")
+    loop_count: 20000000
+  - script: ERB::Util.html_escape("abcd<")
+    loop_count: 20000000
+  - script: ERB::Util.html_escape("'&\"<>")
+    loop_count: 5000000
+  - prelude: long_no_escape = "abcde" * 300
+    script: ERB::Util.html_escape(long_no_escape)
+    loop_count: 1000000
+  - prelude: long_all_escape = "'&\"<>" * 10
+    script: ERB::Util.html_escape(long_all_escape)
+    loop_count: 1000000
+  - prelude: | # http://example.com/
+      example_html = <<~HTML
+        <body>
+        <div>
+            <h1>Example Domain</h1>
+            <p>This domain is established to be used for illustrative examples in documents. You may use this
+            domain in examples without prior coordination or asking for permission.</p>
+            <p><a href="http://www.iana.org/domains/example">More information...</a></p>
+        </div>
+        </body>
+      HTML
+    script: ERB::Util.html_escape(example_html)
+    loop_count: 1000000
diff --git a/benchmark/io_write.rb b/benchmark/io_write.rb
new file mode 100644
index 0000000000..cdb409948b
--- /dev/null
+++ b/benchmark/io_write.rb
@@ -0,0 +1,22 @@
+#!/usr/bin/env ruby
+
+require 'benchmark'
+
+i, o = IO.pipe
+o.sync = true
+
+DOT = ".".freeze
+
+chunks = 100_000.times.collect{DOT}
+
+thread = Thread.new do
+  while i.read(1024)
+  end
+end
+
+100.times do
+  o.write(*chunks)
+end
+
+o.close
+thread.join
diff --git a/benchmark/lib/benchmark_driver/runner/mjit.rb b/benchmark/lib/benchmark_driver/runner/mjit.rb
index 1d4693e8be..3a58a620de 100644
--- a/benchmark/lib/benchmark_driver/runner/mjit.rb
+++ b/benchmark/lib/benchmark_driver/runner/mjit.rb
@@ -16,7 +16,7 @@ class BenchmarkDriver::Runner::Mjit < BenchmarkDriver::Runner::Ips
         job.prelude = "#{job.prelude}\n#{<<~EOS}"
           if defined?(RubyVM::MJIT) && RubyVM::MJIT.enabled?
             __bmdv_ruby_i = 0
-            while __bmdv_ruby_i < 10000 # jit_min_calls
+            while __bmdv_ruby_i < 10000 # MJIT call threshold
               #{job.script}
               __bmdv_ruby_i += 1
             end
diff --git a/benchmark/lib/benchmark_driver/runner/mjit_exec.rb b/benchmark/lib/benchmark_driver/runner/mjit_exec.rb
deleted file mode 100644
index eac3dfba84..0000000000
--- a/benchmark/lib/benchmark_driver/runner/mjit_exec.rb
+++ /dev/null
@@ -1,237 +0,0 @@
-require 'benchmark_driver/struct'
-require 'benchmark_driver/metric'
-require 'erb'
-
-# A special runner dedicated for measuring mjit_exec overhead.
-class BenchmarkDriver::Runner::MjitExec
-  METRIC = BenchmarkDriver::Metric.new(name: 'Iteration per second', unit: 'i/s')
-
-  # JobParser returns this, `BenchmarkDriver::Runner.runner_for` searches "*::Job"
-  Job = ::BenchmarkDriver::Struct.new(
-    :name,        # @param [String] name - This is mandatory for all runner
-    :metrics,     # @param [Array<BenchmarkDriver::Metric>]
-    :num_methods, # @param [Integer] num_methods - The number of methods to be defined
-    :loop_count,  # @param [Integer] loop_count
-    :from_jit,    # @param [TrueClass,FalseClass] from_jit - Whether the mjit_exec() is from JIT or not
-    :to_jit,      # @param [TrueClass,FalseClass] to_jit - Whether the mjit_exec() is to JIT or not
-  )
-  # Dynamically fetched and used by `BenchmarkDriver::JobParser.parse`
-  class << JobParser = Module.new
-    # @param [Array,String] num_methods
-    # @param [Integer] loop_count
-    # @param [TrueClass,FalseClass] from_jit
-    # @param [TrueClass,FalseClass] to_jit
-    def parse(num_methods:, loop_count:, from_jit:, to_jit:)
-      if num_methods.is_a?(String)
-        num_methods = eval(num_methods)
-      end
-
-      num_methods.map do |num|
-        if num_methods.size > 1
-          suffix = "[#{'%4d' % num}]"
-        else
-          suffix = "_#{num}"
-        end
-        Job.new(
-          name: "mjit_exec_#{from_jit ? 'JT' : 'VM'}2#{to_jit ? 'JT' : 'VM'}#{suffix}",
-          metrics: [METRIC],
-          num_methods: num,
-          loop_count: loop_count,
-          from_jit: from_jit,
-          to_jit: to_jit,
-        )
-      end
-    end
-  end
-
-  # @param [BenchmarkDriver::Config::RunnerConfig] config
-  # @param [BenchmarkDriver::Output] output
-  # @param [BenchmarkDriver::Context] contexts
-  def initialize(config:, output:, contexts:)
-    @config = config
-    @output = output
-    @contexts = contexts
-  end
-
-  # This method is dynamically called by `BenchmarkDriver::JobRunner.run`
-  # @param [Array<BenchmarkDriver::Runner::Peak::Job>] jobs
-  def run(jobs)
-    @output.with_benchmark do
-      jobs.each do |job|
-        @output.with_job(name: job.name) do
-          @contexts.each do |context|
-            result = BenchmarkDriver::Repeater.with_repeat(config: @config, larger_better: true, rest_on_average: :average) do
-              run_benchmark(job, context: context)
-            end
-            value, duration = result.value
-            @output.with_context(name: context.name, executable: context.executable, gems: context.gems, prelude: context.prelude) do
-              @output.report(values: { METRIC => value }, duration: duration, loop_count: job.loop_count)
-            end
-          end
-        end
-      end
-    end
-  end
-
-  private
-
-  # @param [BenchmarkDriver::Runner::Ips::Job] job - loop_count is not nil
-  # @param [BenchmarkDriver::Context] context
-  # @return [BenchmarkDriver::Metrics]
-  def run_benchmark(job, context:)
-    if job.from_jit
-      if job.to_jit
-        benchmark = BenchmarkJT2JT.new(num_methods: job.num_methods, loop_count: job.loop_count)
-      else
-        raise NotImplementedError, "JT2VM is not implemented yet"
-      end
-    else
-      if job.to_jit
-        benchmark = BenchmarkVM2JT.new(num_methods: job.num_methods, loop_count: job.loop_count)
-      else
-        benchmark = BenchmarkVM2VM.new(num_methods: job.num_methods, loop_count: job.loop_count)
-      end
-    end
-
-    duration = Tempfile.open(['benchmark_driver-result', '.txt']) do |f|
-      with_script(benchmark.render(result: f.path)) do |path|
-        opt = []
-        if context.executable.command.any? { |c| c.start_with?('--jit') }
-          opt << '--jit-min-calls=2'
-        end
-        IO.popen([*context.executable.command, '--disable-gems', *opt, path], &:read)
-        if $?.success?
-          Float(f.read)
-        else
-          BenchmarkDriver::Result::ERROR
-        end
-      end
-    end
-
-    [job.loop_count.to_f / duration, duration]
-  end
-
-  def with_script(script)
-    if @config.verbose >= 2
-      sep = '-' * 30
-      $stdout.puts "\n\n#{sep}[Script begin]#{sep}\n#{script}#{sep}[Script end]#{sep}\n\n"
-    end
-
-    Tempfile.open(['benchmark_driver-', '.rb']) do |f|
-      f.puts script
-      f.close
-      return yield(f.path)
-    end
-  end
-
-  # @param [Integer] num_methods
-  # @param [Integer] loop_count
-  BenchmarkVM2VM = ::BenchmarkDriver::Struct.new(:num_methods, :loop_count) do
-    # @param [String] result - A file to write result
-    def render(result:)
-      ERB.new(<<~EOS, trim_mode: '%').result(binding)
-        % num_methods.times do |i|
-        def a<%= i %>
-          nil
-        end
-        % end
-        RubyVM::MJIT.pause if defined?(RubyVM::MJIT) && RubyVM::MJIT.enabled?
-
-        def vm
-          t = Process.clock_gettime(Process::CLOCK_MONOTONIC)
-          i = 0
-          while i < <%= loop_count / 1000 %>
-        % 1000.times do |i|
-            a<%= i % num_methods %>
-        % end
-            i += 1
-          end
-        % (loop_count % 1000).times do |i|
-          a<%= i % num_methods %>
-        % end
-          Process.clock_gettime(Process::CLOCK_MONOTONIC) - t
-        end
-
-        vm # warmup call cache
-        File.write(<%= result.dump %>, vm)
-      EOS
-    end
-  end
-  private_constant :BenchmarkVM2VM
-
-  # @param [Integer] num_methods
-  # @param [Integer] loop_count
-  BenchmarkVM2JT = ::BenchmarkDriver::Struct.new(:num_methods, :loop_count) do
-    # @param [String] result - A file to write result
-    def render(result:)
-      ERB.new(<<~EOS, trim_mode: '%').result(binding)
-        % num_methods.times do |i|
-        def a<%= i %>
-          nil
-        end
-        a<%= i %>
-        a<%= i %> # --jit-min-calls=2
-        % end
-        RubyVM::MJIT.pause if defined?(RubyVM::MJIT) && RubyVM::MJIT.enabled?
-
-        def vm
-          t = Process.clock_gettime(Process::CLOCK_MONOTONIC)
-          i = 0
-          while i < <%= loop_count / 1000 %>
-        % 1000.times do |i|
-            a<%= i % num_methods %>
-        % end
-            i += 1
-          end
-        % (loop_count % 1000).times do |i|
-          a<%= i % num_methods %>
-        % end
-          Process.clock_gettime(Process::CLOCK_MONOTONIC) - t
-        end
-
-        vm # warmup call cache
-        File.write(<%= result.dump %>, vm)
-      EOS
-    end
-  end
-  private_constant :BenchmarkVM2JT
-
-  # @param [Integer] num_methods
-  # @param [Integer] loop_count
-  BenchmarkJT2JT = ::BenchmarkDriver::Struct.new(:num_methods, :loop_count) do
-    # @param [String] result - A file to write result
-    def render(result:)
-      ERB.new(<<~EOS, trim_mode: '%').result(binding)
-        % num_methods.times do |i|
-        def a<%= i %>
-          nil
-        end
-        % end
-
-        # You may need to:
-        #   * Increase `JIT_ISEQ_SIZE_THRESHOLD` to 10000000 in mjit.h
-        #   * Always return false in `inlinable_iseq_p()` of mjit_compile.c
-        def jit
-          t = Process.clock_gettime(Process::CLOCK_MONOTONIC)
-          i = 0
-          while i < <%= loop_count / 1000 %>
-        % 1000.times do |i|
-            a<%= i % num_methods %>
-        % end
-            i += 1
-          end
-        % (loop_count % 1000).times do |i|
-          a<%= i % num_methods %>
-        % end
-          Process.clock_gettime(Process::CLOCK_MONOTONIC) - t
-        end
-
-        jit
-        jit
-        RubyVM::MJIT.pause if defined?(RubyVM::MJIT) && RubyVM::MJIT.enabled?
-        File.write(<%= result.dump %>, jit)
-      EOS
-    end
-  end
-  private_constant :BenchmarkJT2JT
-end
diff --git a/benchmark/marshal_dump_load_integer.yml b/benchmark/marshal_dump_load_integer.yml
new file mode 100644
index 0000000000..78ebf823d2
--- /dev/null
+++ b/benchmark/marshal_dump_load_integer.yml
@@ -0,0 +1,22 @@
+prelude: |
+  smallint_array = 1000.times.map { |x| x }
+  bigint32_array = 1000.times.map { |x| x + 2**32 }
+  bigint64_array = 1000.times.map { |x| x + 2**64 }
+
+  smallint_dump = Marshal.dump(smallint_array)
+  bigint32_dump = Marshal.dump(bigint32_array)
+  bigint64_dump = Marshal.dump(bigint64_array)
+benchmark:
+  marshal_dump_integer_small: |
+    Marshal.dump(smallint_array)
+  marshal_dump_integer_over_32_bit: |
+    Marshal.dump(bigint32_array)
+  marshal_dump_integer_over_64_bit: |
+    Marshal.dump(bigint64_array)
+  marshal_load_integer_small: |
+    Marshal.load(smallint_dump)
+  marshal_load_integer_over_32_bit: |
+    Marshal.load(bigint32_dump)
+  marshal_load_integer_over_64_bit: |
+    Marshal.load(bigint64_dump)
+loop_count: 4000
diff --git a/benchmark/masgn.yml b/benchmark/masgn.yml
index 4be9333e23..31cb8ee4a3 100644
--- a/benchmark/masgn.yml
+++ b/benchmark/masgn.yml
@@ -1,7 +1,7 @@
 prelude: |
   a = [nil] * 3
   b = Class.new{attr_writer :a, :b, :c}.new
-  c, d, e, f = nil, nil, nil, nil
+  c = d = e = f = g = h = i = nil
 benchmark:
   array2_2: "c = (a[0], a[1] = 1, 2)"
   array2_3: "c = (a[0], a[1] = 1, 2, 3)"
@@ -27,3 +27,27 @@ benchmark:
   lvar2_3p: "(d, e = 1, 2, 3; nil)"
   lvar3_2p: "(d, e, f = 1, 2; nil)"
   lvar3_3p: "(d, e, f = 1, 2, 3; nil)"
+  array2_2lv: "c = (a[0], a[1] = g, h)"
+  array2_ilv: "c = (a[0], a[1] = g, h, i)"
+  arrayi_2lv: "c = (a[0], a[1], a[2] = g, h)"
+  arrayi_ilv: "c = (a[0], a[1], a[2] = g, h, i)"
+  attr2_2lv: "c = (b.a, b.b = g, h)"
+  attr2_ilv: "c = (b.a, b.b = g, h, i)"
+  attri_2lv: "c = (b.a, b.b, b.c = g, h)"
+  attri_ilv: "c = (b.a, b.b, b.c = g, h, i)"
+  lvar2_2lv: "c = (d, e = g, h)"
+  lvar2_ilv: "c = (d, e = g, h, i)"
+  lvari_2lv: "c = (d, e, f = g, h)"
+  lvari_ilv: "c = (d, e, f = g, h, i)"
+  array2_2plv: "(a[0], a[1] = g, h; nil)"
+  array2_iplv: "(a[0], a[1] = g, h, i; nil)"
+  arrayi_2plv: "(a[0], a[1], a[2] = g, h; nil)"
+  arrayi_iplv: "(a[0], a[1], a[2] = g, h, i; nil)"
+  attr2_2plv: "(b.a, b.b = g, h; nil)"
+  attr2_iplv: "(b.a, b.b = g, h, i; nil)"
+  attri_2plv: "(b.a, b.b, b.c = g, h; nil)"
+  attri_iplv: "(b.a, b.b, b.c = g, h, i; nil)"
+  lvar2_2plv: "(d, e = g, h; nil)"
+  lvar2_iplv: "(d, e = g, h, i; nil)"
+  lvari_2plv: "(d, e, f = g, h; nil)"
+  lvari_iplv: "(d, e, f = g, h, i; nil)"
diff --git a/benchmark/mjit_exec_jt2jt.yml b/benchmark/mjit_exec_jt2jt.yml
deleted file mode 100644
index 6c303c7a44..0000000000
--- a/benchmark/mjit_exec_jt2jt.yml
+++ /dev/null
@@ -1,6 +0,0 @@
-type: lib/benchmark_driver/runner/mjit_exec
-num_methods: [1]
-#num_methods: (1..100).to_a + [200, 300, 400, 500, 600, 700, 800, 900, 1000]
-loop_count: 50000000
-from_jit: true
-to_jit: true
diff --git a/benchmark/mjit_exec_vm2jt.yml b/benchmark/mjit_exec_vm2jt.yml
deleted file mode 100644
index 764883f070..0000000000
--- a/benchmark/mjit_exec_vm2jt.yml
+++ /dev/null
@@ -1,6 +0,0 @@
-type: lib/benchmark_driver/runner/mjit_exec
-num_methods: [1]
-#num_methods: (1..100).to_a + [200, 300, 400, 500, 600, 700, 800, 900, 1000]
-loop_count: 50000000
-from_jit: false
-to_jit: true
diff --git a/benchmark/mjit_exec_vm2vm.yml b/benchmark/mjit_exec_vm2vm.yml
deleted file mode 100644
index 030aa76c1c..0000000000
--- a/benchmark/mjit_exec_vm2vm.yml
+++ /dev/null
@@ -1,6 +0,0 @@
-type: lib/benchmark_driver/runner/mjit_exec
-num_methods: [1]
-#num_methods: (1..100).to_a + [200, 300, 400, 500, 600, 700, 800, 900, 1000]
-loop_count: 50000000
-from_jit: false
-to_jit: false
diff --git a/benchmark/numeric_methods.yml b/benchmark/numeric_methods.yml
index 433c2268a3..1384902935 100644
--- a/benchmark/numeric_methods.yml
+++ b/benchmark/numeric_methods.yml
@@ -10,4 +10,20 @@ benchmark:
     int.finite?
   infinite?: |
     int.infinite?
+  integer_real: |
+    int.real
+  float_real: |
+    flo.real
+  integr_imag: |
+    int.imag
+  float_imag: |
+    flo.imag
+  integer_conj: |
+    int.conj
+  float_conj: |
+    flo.conj
+  integer_numerator: |
+    int.numerator
+  integer_denominator: |
+    int.denominator
 loop_count: 20000000
diff --git a/benchmark/range_min.yml b/benchmark/range_min.yml
new file mode 100644
index 0000000000..9e60dd7308
--- /dev/null
+++ b/benchmark/range_min.yml
@@ -0,0 +1,2 @@
+benchmark:
+  - (1..10).min
diff --git a/benchmark/so_nbody.rb b/benchmark/so_nbody.rb
index d6c5bb9e61..9884fc4edc 100644
--- a/benchmark/so_nbody.rb
+++ b/benchmark/so_nbody.rb
@@ -12,38 +12,38 @@ def _puts *args
 end
 
 class Planet
- attr_accessor :x, :y, :z, :vx, :vy, :vz, :mass
+  attr_accessor :x, :y, :z, :vx, :vy, :vz, :mass
 
- def initialize(x, y, z, vx, vy, vz, mass)
-  @x, @y, @z = x, y, z
-  @vx, @vy, @vz = vx * DAYS_PER_YEAR, vy * DAYS_PER_YEAR, vz * DAYS_PER_YEAR
-  @mass = mass * SOLAR_MASS
- end
-
- def move_from_i(bodies, nbodies, dt, i)
-  while i < nbodies
-   b2 = bodies[i]
-   dx = @x - b2.x
-   dy = @y - b2.y
-   dz = @z - b2.z
-
-   distance = Math.sqrt(dx * dx + dy * dy + dz * dz)
-   mag = dt / (distance * distance * distance)
-   b_mass_mag, b2_mass_mag = @mass * mag, b2.mass * mag
-
-   @vx -= dx * b2_mass_mag
-   @vy -= dy * b2_mass_mag
-   @vz -= dz * b2_mass_mag
-   b2.vx += dx * b_mass_mag
-   b2.vy += dy * b_mass_mag
-   b2.vz += dz * b_mass_mag
-   i += 1
+  def initialize(x, y, z, vx, vy, vz, mass)
+    @x, @y, @z = x, y, z
+    @vx, @vy, @vz = vx * DAYS_PER_YEAR, vy * DAYS_PER_YEAR, vz * DAYS_PER_YEAR
+    @mass = mass * SOLAR_MASS
   end
 
-  @x += dt * @vx
-  @y += dt * @vy
-  @z += dt * @vz
- end
+  def move_from_i(bodies, nbodies, dt, i)
+    while i < nbodies
+      b2 = bodies[i]
+      dx = @x - b2.x
+      dy = @y - b2.y
+      dz = @z - b2.z
+
+      distance = Math.sqrt(dx * dx + dy * dy + dz * dz)
+      mag = dt / (distance * distance * distance)
+      b_mass_mag, b2_mass_mag = @mass * mag, b2.mass * mag
+
+      @vx -= dx * b2_mass_mag
+      @vy -= dy * b2_mass_mag
+      @vz -= dz * b2_mass_mag
+      b2.vx += dx * b_mass_mag
+      b2.vy += dy * b_mass_mag
+      b2.vz += dz * b_mass_mag
+      i += 1
+    end
+
+    @x += dt * @vx
+    @y += dt * @vy
+    @z += dt * @vz
+  end
 end
 
 def energy(bodies)
diff --git a/benchmark/string_concat.yml b/benchmark/string_concat.yml
new file mode 100644
index 0000000000..e65c00cca9
--- /dev/null
+++ b/benchmark/string_concat.yml
@@ -0,0 +1,45 @@
+prelude: |
+  CHUNK = "a" * 64
+  UCHUNK = "é" * 32
+  GC.disable # GC causes a lot of variance
+benchmark:
+  binary_concat_7bit: |
+    buffer = String.new(capacity: 4096, encoding: Encoding::BINARY)
+    buffer << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK
+    buffer << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK
+    buffer << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK
+    buffer << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK
+    buffer << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK
+    buffer << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK
+    buffer << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK
+    buffer << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK
+  utf8_concat_7bit: |
+    buffer = String.new(capacity: 4096, encoding: Encoding::UTF_8)
+    buffer << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK
+    buffer << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK
+    buffer << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK
+    buffer << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK
+    buffer << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK
+    buffer << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK
+    buffer << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK
+    buffer << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK << CHUNK
+  utf8_concat_UTF8: |
+    buffer = String.new(capacity: 4096, encoding: Encoding::UTF_8)
+    buffer << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK
+    buffer << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK
+    buffer << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK
+    buffer << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK
+    buffer << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK
+    buffer << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK
+    buffer << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK
+    buffer << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK << UCHUNK
+  interpolation: |
+    buffer = "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}" \
+      "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}" \
+      "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}" \
+      "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}" \
+      "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}" \
+      "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}" \
+      "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}" \
+      "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}" \
+      "#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}#{CHUNK}"
diff --git a/benchmark/time_parse.yml b/benchmark/time_parse.yml
index a6d6948b9c..6060b58bc6 100644
--- a/benchmark/time_parse.yml
+++ b/benchmark/time_parse.yml
@@ -6,3 +6,5 @@ benchmark:
   - Time.iso8601(iso8601)
   - Time.parse(iso8601)
   - Time.parse(inspect)
+  - Time.new(iso8601) rescue Time.iso8601(iso8601)
+  - Time.new(inspect) rescue Time.parse(inspect)
diff --git a/benchmark/vm_const.yml b/benchmark/vm_const.yml
index 6064d4eed0..8939ca0cd3 100644
--- a/benchmark/vm_const.yml
+++ b/benchmark/vm_const.yml
@@ -1,7 +1,13 @@
 prelude: |
   Const = 1
+  A = B = C = D = E = F = G = H = I = J = K = L = M = N = O = P = Q = R = S = T = U = V = W = X = Y = Z = 1
+  def foo
+    A; B; C; D; E; F; G; H; I; J; K; L; M; N; O; P; Q; R; S; T; U; V; W; X; Y; Z
+  end
 benchmark:
   vm_const: |
     j = Const
     k = Const
+  vm_const_many: |
+    foo
 loop_count: 30000000
diff --git a/benchmark/vm_freezeobj.yml b/benchmark/vm_freezeobj.yml
new file mode 100644
index 0000000000..69a795a354
--- /dev/null
+++ b/benchmark/vm_freezeobj.yml
@@ -0,0 +1,6 @@
+prelude: |
+ objs = 100000.times.map { Object.new }
+benchmark:
+  vm_freeze_obj: |
+    objs.map(&:freeze)
+loop_count: 600
diff --git a/benchmark/vm_ivar_embedded_obj_init.yml b/benchmark/vm_ivar_embedded_obj_init.yml
new file mode 100644
index 0000000000..74fe20a630
--- /dev/null
+++ b/benchmark/vm_ivar_embedded_obj_init.yml
@@ -0,0 +1,14 @@
+prelude: |
+  class C
+    def set_ivars
+      @a = nil
+      @b = nil
+      @c = nil
+    end
+  end
+
+  c = C.new
+benchmark:
+  vm_ivar_embedded_obj_init: |
+    c.set_ivars
+loop_count: 30000000
diff --git a/benchmark/vm_ivar_init.yml b/benchmark/vm_ivar_extended_obj_init.yml
index c6f1633907..f054bab282 100644
--- a/benchmark/vm_ivar_init.yml
+++ b/benchmark/vm_ivar_extended_obj_init.yml
@@ -1,6 +1,6 @@
 prelude: |
   class C
-    def initialize
+    def set_ivars
       @a = nil
       @b = nil
       @c = nil
@@ -8,7 +8,9 @@ prelude: |
       @e = nil
     end
   end
+
+  c = C.new
 benchmark:
-  vm_ivar_init: |
-    C.new
+  vm_ivar_extended_obj_init: |
+    c.set_ivars
 loop_count: 30000000
diff --git a/benchmark/vm_ivar_generic_get.yml b/benchmark/vm_ivar_generic_get.yml
new file mode 100644
index 0000000000..dae2d37671
--- /dev/null
+++ b/benchmark/vm_ivar_generic_get.yml
@@ -0,0 +1,17 @@
+prelude: |
+  class C < Array
+    attr_reader :a, :b, :c
+    def initialize
+      @a = nil
+      @b = nil
+      @c = nil
+    end
+  end
+
+  c = C.new
+benchmark:
+  vm_ivar_generic_get: |
+    c.a
+    c.b
+    c.c
+loop_count: 30000000
diff --git a/benchmark/vm_ivar_generic_set.yml b/benchmark/vm_ivar_generic_set.yml
new file mode 100644
index 0000000000..102a6577fb
--- /dev/null
+++ b/benchmark/vm_ivar_generic_set.yml
@@ -0,0 +1,14 @@
+prelude: |
+  class C < Array
+    def set_ivars
+      @a = nil
+      @b = nil
+      @c = nil
+    end
+  end
+
+  c = C.new
+benchmark:
+  vm_ivar_generic_set: |
+    c.set_ivars
+loop_count: 30000000
diff --git a/benchmark/vm_ivar_get.yml b/benchmark/vm_ivar_get.yml
new file mode 100644
index 0000000000..9174af6965
--- /dev/null
+++ b/benchmark/vm_ivar_get.yml
@@ -0,0 +1,37 @@
+prelude: |
+  class Example
+    def initialize
+      @v0 = 1
+      @v1 = 2
+      @v3 = 3
+      @levar = 1
+    end
+
+    def get_value_loop
+      sum = 0
+
+      i = 0
+      while i < 1000000
+        # 10 times to de-emphasize loop overhead
+        sum += @levar
+        sum += @levar
+        sum += @levar
+        sum += @levar
+        sum += @levar
+        sum += @levar
+        sum += @levar
+        sum += @levar
+        sum += @levar
+        sum += @levar
+        i += 1
+      end
+
+      return sum
+    end
+  end
+
+  obj = Example.new
+benchmark:
+  vm_ivar_get: |
+    obj.get_value_loop
+loop_count: 100
diff --git a/benchmark/vm_ivar_get_unintialized.yml b/benchmark/vm_ivar_get_unintialized.yml
new file mode 100644
index 0000000000..a1ccfb06ce
--- /dev/null
+++ b/benchmark/vm_ivar_get_unintialized.yml
@@ -0,0 +1,12 @@
+prelude: |
+  class Example
+    def read
+      @uninitialized
+    end
+  end
+
+  obj = Example.new
+benchmark:
+  vm_ivar_get_uninitialized: |
+    obj.read
+loop_count: 30000000
diff --git a/benchmark/vm_ivar_lazy_set.yml b/benchmark/vm_ivar_lazy_set.yml
new file mode 100644
index 0000000000..7372ffcfbc
--- /dev/null
+++ b/benchmark/vm_ivar_lazy_set.yml
@@ -0,0 +1,12 @@
+prelude: |
+  class Example
+    def lazy_set
+      @uninitialized ||= 123
+    end
+  end
+
+  objs = 10000000.times.map { Example.new }
+benchmark:
+  vm_ivar_lazy_set: |
+    objs.each(&:lazy_set)
+loop_count: 1
diff --git a/benchmark/vm_ivar_set_on_instance.yml b/benchmark/vm_ivar_set_on_instance.yml
new file mode 100644
index 0000000000..91857b7742
--- /dev/null
+++ b/benchmark/vm_ivar_set_on_instance.yml
@@ -0,0 +1,35 @@
+prelude: |
+  class TheClass
+    def initialize
+      @v0 = 1
+      @v1 = 2
+      @v3 = 3
+      @levar = 1
+    end
+
+    def set_value_loop
+      # 1M
+      i = 0
+      while i < 1000000
+        # 10 times to de-emphasize loop overhead
+        @levar = i
+        @levar = i
+        @levar = i
+        @levar = i
+        @levar = i
+        @levar = i
+        @levar = i
+        @levar = i
+        @levar = i
+        @levar = i
+        i += 1
+      end
+    end
+  end
+
+  obj = TheClass.new
+
+benchmark:
+  vm_ivar_set_on_instance: |
+    obj.set_value_loop
+loop_count: 100
diff --git a/benchmark/vm_ivar_set_subclass.yml b/benchmark/vm_ivar_set_subclass.yml
index 2653d36ded..bc8bf5bf6b 100644
--- a/benchmark/vm_ivar_set_subclass.yml
+++ b/benchmark/vm_ivar_set_subclass.yml
@@ -1,6 +1,6 @@
 prelude: |
   class A
-    def initialize
+    def set_ivars
       @a = nil
       @b = nil
       @c = nil
@@ -10,8 +10,11 @@ prelude: |
   end
   class B < A; end
   class C < A; end
+
+  b = B.new
+  c = C.new
 benchmark:
   vm_ivar_init_subclass: |
-    B.new
-    C.new
+    b.set_ivars
+    c.set_ivars
 loop_count: 3000000
diff --git a/benchmark/vm_lvar_cond_set.yml b/benchmark/vm_lvar_cond_set.yml
new file mode 100644
index 0000000000..1845f9d12e
--- /dev/null
+++ b/benchmark/vm_lvar_cond_set.yml
@@ -0,0 +1,8 @@
+benchmark:
+  vm_lvar_cond_set: |
+    a ||= 1
+    b ||= 1
+    c ||= 1
+    d ||= 1
+    nil
+loop_count: 30000000
diff --git a/bignum.c b/bignum.c
index 142059b8fd..cb2c3b6f07 100644
--- a/bignum.c
+++ b/bignum.c
@@ -23,8 +23,14 @@
 # include <ieeefp.h>
 #endif
 
+#if !defined(USE_GMP)
 #if defined(HAVE_LIBGMP) && defined(HAVE_GMP_H)
-# define USE_GMP
+# define USE_GMP 1
+#else
+# define USE_GMP 0
+#endif
+#endif
+#if USE_GMP
 # include <gmp.h>
 #endif
 
@@ -99,8 +105,8 @@ STATIC_ASSERT(sizeof_long_and_sizeof_bdigit, SIZEOF_BDIGIT % SIZEOF_LONG == 0);
 #endif
 
 #define BIGZEROP(x) (BIGNUM_LEN(x) == 0 || \
-		     (BDIGITS(x)[0] == 0 && \
-		      (BIGNUM_LEN(x) == 1 || bigzero_p(x))))
+                     (BDIGITS(x)[0] == 0 && \
+                      (BIGNUM_LEN(x) == 1 || bigzero_p(x))))
 #define BIGSIZE(x) (BIGNUM_LEN(x) == 0 ? (size_t)0 : \
     BDIGITS(x)[BIGNUM_LEN(x)-1] ? \
         (size_t)(BIGNUM_LEN(x)*SIZEOF_BDIGIT - nlz(BDIGITS(x)[BIGNUM_LEN(x)-1])/CHAR_BIT) : \
@@ -145,7 +151,7 @@ STATIC_ASSERT(sizeof_long_and_sizeof_bdigit, SIZEOF_BDIGIT % SIZEOF_LONG == 0);
 #define GMP_DIV_DIGITS 20
 #define GMP_BIG2STR_DIGITS 20
 #define GMP_STR2BIG_DIGITS 20
-#ifdef USE_GMP
+#if USE_GMP
 # define NAIVE_MUL_DIGITS GMP_MUL_DIGITS
 #else
 # define NAIVE_MUL_DIGITS KARATSUBA_MUL_DIGITS
@@ -413,9 +419,9 @@ bary_small_lshift(BDIGIT *zds, const BDIGIT *xds, size_t n, int shift)
     assert(0 <= shift && shift < BITSPERDIG);
 
     for (i=0; i<n; i++) {
-	num = num | (BDIGIT_DBL)*xds++ << shift;
-	*zds++ = BIGLO(num);
-	num = BIGDN(num);
+        num = num | (BDIGIT_DBL)*xds++ << shift;
+        *zds++ = BIGLO(num);
+        num = BIGDN(num);
     }
     return BIGLO(num);
 }
@@ -431,9 +437,9 @@ bary_small_rshift(BDIGIT *zds, const BDIGIT *xds, size_t n, int shift, BDIGIT hi
     num = BIGUP(higher_bdigit);
     for (i = 0; i < n; i++) {
         BDIGIT x = xds[n - i - 1];
-	num = (num | x) >> shift;
+        num = (num | x) >> shift;
         zds[n - i - 1] = BIGLO(num);
-	num = BIGUP(x);
+        num = BIGUP(x);
     }
 }
 
@@ -443,7 +449,7 @@ bary_zero_p(const BDIGIT *xds, size_t xn)
     if (xn == 0)
         return 1;
     do {
-	if (xds[--xn]) return 0;
+        if (xds[--xn]) return 0;
     } while (xn);
     return 1;
 }
@@ -971,7 +977,7 @@ integer_unpack_num_bdigits_small(size_t numwords, size_t wordsize, size_t nails,
 {
     /* nlp_bits stands for number of leading padding bits */
     size_t num_bits = (wordsize * CHAR_BIT - nails) * numwords;
-    size_t num_bdigits = (num_bits + BITSPERDIG - 1) / BITSPERDIG;
+    size_t num_bdigits = roomof(num_bits, BITSPERDIG);
     *nlp_bits_ret = (int)(num_bdigits * BITSPERDIG - num_bits);
     return num_bdigits;
 }
@@ -981,7 +987,7 @@ integer_unpack_num_bdigits_generic(size_t numwords, size_t wordsize, size_t nail
 {
     /* BITSPERDIG = SIZEOF_BDIGIT * CHAR_BIT */
     /* num_bits = (wordsize * CHAR_BIT - nails) * numwords */
-    /* num_bdigits = (num_bits + BITSPERDIG - 1) / BITSPERDIG */
+    /* num_bdigits = roomof(num_bits, BITSPERDIG) */
 
     /* num_bits = CHAR_BIT * (wordsize * numwords) - nails * numwords = CHAR_BIT * num_bytes1 - nails * numwords */
     size_t num_bytes1 = wordsize * numwords;
@@ -1344,9 +1350,9 @@ bary_subb(BDIGIT *zds, size_t zn, const BDIGIT *xds, size_t xn, const BDIGIT *yd
 
     num = borrow ? -1 : 0;
     for (i = 0; i < sn; i++) {
-	num += (BDIGIT_DBL_SIGNED)xds[i] - yds[i];
-	zds[i] = BIGLO(num);
-	num = BIGDN(num);
+        num += (BDIGIT_DBL_SIGNED)xds[i] - yds[i];
+        zds[i] = BIGLO(num);
+        num = BIGDN(num);
     }
     if (yn <= xn) {
         for (; i < xn; i++) {
@@ -1365,7 +1371,7 @@ bary_subb(BDIGIT *zds, size_t zn, const BDIGIT *xds, size_t xn, const BDIGIT *yd
     }
     if (num == 0) goto num_is_zero;
     for (; i < zn; i++) {
-	zds[i] = BDIGMAX;
+        zds[i] = BDIGMAX;
     }
     return 1;
 
@@ -1373,10 +1379,10 @@ bary_subb(BDIGIT *zds, size_t zn, const BDIGIT *xds, size_t xn, const BDIGIT *yd
     if (xds == zds && xn == zn)
         return 0;
     for (; i < xn; i++) {
-	zds[i] = xds[i];
+        zds[i] = xds[i];
     }
     for (; i < zn; i++) {
-	zds[i] = 0;
+        zds[i] = 0;
     }
     return 0;
 }
@@ -1403,27 +1409,27 @@ bary_addc(BDIGIT *zds, size_t zn, const BDIGIT *xds, size_t xn, const BDIGIT *yd
     assert(yn <= zn);
 
     if (xn > yn) {
-	const BDIGIT *tds;
-	tds = xds; xds = yds; yds = tds;
-	i = xn; xn = yn; yn = i;
+        const BDIGIT *tds;
+        tds = xds; xds = yds; yds = tds;
+        i = xn; xn = yn; yn = i;
     }
 
     num = carry ? 1 : 0;
     for (i = 0; i < xn; i++) {
-	num += (BDIGIT_DBL)xds[i] + yds[i];
-	zds[i] = BIGLO(num);
-	num = BIGDN(num);
+        num += (BDIGIT_DBL)xds[i] + yds[i];
+        zds[i] = BIGLO(num);
+        num = BIGDN(num);
     }
     for (; i < yn; i++) {
         if (num == 0) goto num_is_zero;
-	num += yds[i];
-	zds[i] = BIGLO(num);
-	num = BIGDN(num);
+        num += yds[i];
+        zds[i] = BIGLO(num);
+        num = BIGDN(num);
     }
     for (; i < zn; i++) {
         if (num == 0) goto num_is_zero;
-	zds[i] = BIGLO(num);
-	num = BIGDN(num);
+        zds[i] = BIGLO(num);
+        num = BIGDN(num);
     }
     return num != 0;
 
@@ -1431,10 +1437,10 @@ bary_addc(BDIGIT *zds, size_t zn, const BDIGIT *xds, size_t xn, const BDIGIT *yd
     if (yds == zds && yn == zn)
         return 0;
     for (; i < yn; i++) {
-	zds[i] = yds[i];
+        zds[i] = yds[i];
     }
     for (; i < zn; i++) {
-	zds[i] = 0;
+        zds[i] = 0;
     }
     return 0;
 }
@@ -1591,30 +1597,30 @@ bary_sq_fast(BDIGIT *zds, size_t zn, const BDIGIT *xds, size_t xn)
         return;
 
     for (i = 0; i < xn-1; i++) {
-	v = (BDIGIT_DBL)xds[i];
-	if (!v)
+        v = (BDIGIT_DBL)xds[i];
+        if (!v)
             continue;
-	c = (BDIGIT_DBL)zds[i + i] + v * v;
-	zds[i + i] = BIGLO(c);
-	c = BIGDN(c);
-	v *= 2;
+        c = (BDIGIT_DBL)zds[i + i] + v * v;
+        zds[i + i] = BIGLO(c);
+        c = BIGDN(c);
+        v *= 2;
         vl = BIGLO(v);
         vh = (int)BIGDN(v);
-	for (j = i + 1; j < xn; j++) {
-	    w = (BDIGIT_DBL)xds[j];
-	    c += (BDIGIT_DBL)zds[i + j] + vl * w;
-	    zds[i + j] = BIGLO(c);
-	    c = BIGDN(c);
-	    if (vh)
+        for (j = i + 1; j < xn; j++) {
+            w = (BDIGIT_DBL)xds[j];
+            c += (BDIGIT_DBL)zds[i + j] + vl * w;
+            zds[i + j] = BIGLO(c);
+            c = BIGDN(c);
+            if (vh)
                 c += w;
-	}
-	if (c) {
-	    c += (BDIGIT_DBL)zds[i + xn];
-	    zds[i + xn] = BIGLO(c);
-	    c = BIGDN(c);
+        }
+        if (c) {
+            c += (BDIGIT_DBL)zds[i + xn];
+            zds[i + xn] = BIGLO(c);
+            c = BIGDN(c);
             if (c)
                 zds[i + xn + 1] += (BDIGIT)c;
-	}
+        }
     }
 
     /* i == xn-1 */
@@ -1639,6 +1645,12 @@ rb_big_sq_fast(VALUE x)
     return z;
 }
 
+static inline size_t
+max_size(size_t a, size_t b)
+{
+    return (a > b ? a : b);
+}
+
 /* balancing multiplication by slicing larger argument */
 static void
 bary_mul_balance_with_mulfunc(BDIGIT *const zds, const size_t zn,
@@ -1656,8 +1668,14 @@ bary_mul_balance_with_mulfunc(BDIGIT *const zds, const size_t zn,
     BDIGITS_ZERO(zds, xn);
 
     if (wn < xn) {
-        const size_t r = (yn % xn) ? (yn % xn) : xn;
-        if ((2 * xn + yn + r) > zn) {
+        /* The condition when a new buffer is needed:
+         * 1. (2(xn+r) > zn-(yn-r)) => (2xn+r > zn-yn), at the last
+         *    iteration (or r == 0)
+         * 2. (2(xn+xn) > zn-(yn-r-xn)) => (3xn-r > zn-yn), at the
+         *    previous iteration.
+         */
+        const size_t r = yn % xn;
+        if (2*xn + yn + max_size(xn-r, r) > zn) {
             wn = xn;
             wds = ALLOCV_N(BDIGIT, work, wn);
         }
@@ -1692,7 +1710,7 @@ bary_mul_balance_with_mulfunc(BDIGIT *const zds, const size_t zn,
                      zds + n, tn,
                      wds, xn);
         }
-	n += r;
+        n += r;
     }
     BDIGITS_ZERO(zds+xn+yn, zn - (xn+yn));
 
@@ -2084,21 +2102,21 @@ bary_mul_toom3(BDIGIT *zds, size_t zn, const BDIGIT *xds, size_t xn, const BDIGI
         v3n = u3n; v3ds = u3ds; v3p = u3p;
     }
     else {
-	/* v1 <- y0 + y2 */
+        /* v1 <- y0 + y2 */
         bary_add(v1ds, v1n, y0ds, y0n, y2ds, y2n);
         v1p = 1;
 
-	/* y(-1) : v2 <- v1 - y1 = y0 - y1 + y2 */
+        /* y(-1) : v2 <- v1 - y1 = y0 - y1 + y2 */
         v2p = 1;
         if (bary_sub(v2ds, v2n, v1ds, v1n, y1ds, y1n)) {
             bary_2comp(v2ds, v2n);
             v2p = 0;
         }
 
-	/* y(1) : v1 <- v1 + y1 = y0 + y1 + y2 */
+        /* y(1) : v1 <- v1 + y1 = y0 + y1 + y2 */
         bary_add(v1ds, v1n, v1ds, v1n, y1ds, y1n);
 
-	/* y(-2) : v3 <- 2 * (v2 + y2) - y0 = y0 - 2 * (y1 - 2 * y2) */
+        /* y(-2) : v3 <- 2 * (v2 + y2) - y0 = y0 - 2 * (y1 - 2 * y2) */
         v3p = 1;
         if (v2p) {
             bary_add(v3ds, v3n, v2ds, v2n, y2ds, y2n);
@@ -2291,7 +2309,7 @@ rb_big_mul_toom3(VALUE x, VALUE y)
     return z;
 }
 
-#ifdef USE_GMP
+#if USE_GMP
 static inline void
 bdigits_to_mpz(mpz_t mp, const BDIGIT *digits, size_t len)
 {
@@ -2429,8 +2447,8 @@ bary_mul_precheck(BDIGIT **zdsp, size_t *znp, const BDIGIT **xdsp, size_t *xnp,
     if (xn > yn) {
         const BDIGIT *tds;
         size_t tn;
-	tds = xds; xds = yds; yds = tds;
-	tn = xn; xn = yn; yn = tn;
+        tds = xds; xds = yds; yds = tds;
+        tn = xn; xn = yn; yn = tn;
     }
     assert(xn <= yn);
 
@@ -2556,7 +2574,7 @@ bary_mul(BDIGIT *zds, size_t zn, const BDIGIT *xds, size_t xn, const BDIGIT *yds
         }
     }
 
-#ifdef USE_GMP
+#if USE_GMP
     bary_mul_gmp(zds, zn, xds, xn, yds, yn);
 #else
     bary_mul_toom3_start(zds, zn, xds, xn, yds, yn, NULL, 0);
@@ -2580,26 +2598,26 @@ bigdivrem1(void *ptr)
     BDIGIT q;
 
     do {
-	if (bds->stop) {
-	    bds->zn = zn;
-	    return 0;
+        if (bds->stop) {
+            bds->zn = zn;
+            return 0;
         }
-	if (zds[zn-1] == yds[yn-1]) q = BDIGMAX;
-	else q = (BDIGIT)((BIGUP(zds[zn-1]) + zds[zn-2])/yds[yn-1]);
-	if (q) {
+        if (zds[zn-1] == yds[yn-1]) q = BDIGMAX;
+        else q = (BDIGIT)((BIGUP(zds[zn-1]) + zds[zn-2])/yds[yn-1]);
+        if (q) {
             num = bigdivrem_mulsub(zds+zn-(yn+1), yn+1,
                                    q,
                                    yds, yn);
-	    while (num) { /* "add back" required */
-		q--;
+            while (num) { /* "add back" required */
+                q--;
                 num = bary_add(zds+zn-(yn+1), yn,
                                zds+zn-(yn+1), yn,
                                yds, yn);
                 num--;
-	    }
-	}
+            }
+        }
         zn--;
-	zds[zn] = q;
+        zds[zn] = q;
     } while (zn > yn);
     return 0;
 }
@@ -2668,16 +2686,16 @@ bigdivrem_restoring(BDIGIT *zds, size_t zn, BDIGIT *yds, size_t yn)
     bds.zn = zn - ynzero;
     if (bds.zn > 10000 || bds.yn > 10000) {
       retry:
-	bds.stop = Qfalse;
+        bds.stop = Qfalse;
         rb_nogvl(bigdivrem1, &bds, rb_big_stop, &bds, RB_NOGVL_UBF_ASYNC_SAFE);
 
-	if (bds.stop == Qtrue) {
-	    /* execute trap handler, but exception was not raised. */
-	    goto retry;
-	}
+        if (bds.stop == Qtrue) {
+            /* execute trap handler, but exception was not raised. */
+            goto retry;
+        }
     }
     else {
-	bigdivrem1(&bds);
+        bigdivrem1(&bds);
     }
 }
 
@@ -2776,7 +2794,7 @@ rb_big_divrem_normal(VALUE x, VALUE y)
     return rb_assoc_new(q, r);
 }
 
-#ifdef USE_GMP
+#if USE_GMP
 static void
 bary_divmod_gmp(BDIGIT *qds, size_t qn, BDIGIT *rds, size_t rn, const BDIGIT *xds, size_t xn, const BDIGIT *yds, size_t yn)
 {
@@ -2860,7 +2878,7 @@ rb_big_divrem_gmp(VALUE x, VALUE y)
 static void
 bary_divmod_branch(BDIGIT *qds, size_t qn, BDIGIT *rds, size_t rn, const BDIGIT *xds, size_t xn, const BDIGIT *yds, size_t yn)
 {
-#ifdef USE_GMP
+#if USE_GMP
     if (GMP_DIV_DIGITS < xn) {
         bary_divmod_gmp(qds, qn, rds, rn, xds, xn, yds, yn);
         return;
@@ -2935,7 +2953,7 @@ int
 rb_cmpint(VALUE val, VALUE a, VALUE b)
 {
     if (NIL_P(val)) {
-	rb_cmperr(a, b);
+        rb_cmperr(a, b);
     }
     if (FIXNUM_P(val)) {
         long l = FIX2LONG(val);
@@ -2944,9 +2962,9 @@ rb_cmpint(VALUE val, VALUE a, VALUE b)
         return 0;
     }
     if (RB_BIGNUM_TYPE_P(val)) {
-	if (BIGZEROP(val)) return 0;
-	if (BIGNUM_SIGN(val)) return 1;
-	return -1;
+        if (BIGZEROP(val)) return 0;
+        if (BIGNUM_SIGN(val)) return 1;
+        return -1;
     }
     if (RTEST(rb_funcall(val, '>', 1, INT2FIX(0)))) return 1;
     if (RTEST(rb_funcall(val, '<', 1, INT2FIX(0)))) return -1;
@@ -2956,8 +2974,8 @@ rb_cmpint(VALUE val, VALUE a, VALUE b)
 #define BIGNUM_SET_LEN(b,l) \
     (BIGNUM_EMBED_P(b) ? \
      (void)(RBASIC(b)->flags = \
-	    (RBASIC(b)->flags & ~BIGNUM_EMBED_LEN_MASK) | \
-	    ((l) << BIGNUM_EMBED_LEN_SHIFT)) : \
+            (RBASIC(b)->flags & ~BIGNUM_EMBED_LEN_MASK) | \
+            ((l) << BIGNUM_EMBED_LEN_SHIFT)) : \
      (void)(RBIGNUM(b)->as.heap.len = (l)))
 
 static void
@@ -2965,33 +2983,33 @@ rb_big_realloc(VALUE big, size_t len)
 {
     BDIGIT *ds;
     if (BIGNUM_EMBED_P(big)) {
-	if (BIGNUM_EMBED_LEN_MAX < len) {
-	    ds = ALLOC_N(BDIGIT, len);
-	    MEMCPY(ds, RBIGNUM(big)->as.ary, BDIGIT, BIGNUM_EMBED_LEN_MAX);
-	    RBIGNUM(big)->as.heap.len = BIGNUM_LEN(big);
-	    RBIGNUM(big)->as.heap.digits = ds;
+        if (BIGNUM_EMBED_LEN_MAX < len) {
+            ds = ALLOC_N(BDIGIT, len);
+            MEMCPY(ds, RBIGNUM(big)->as.ary, BDIGIT, BIGNUM_EMBED_LEN_MAX);
+            RBIGNUM(big)->as.heap.len = BIGNUM_LEN(big);
+            RBIGNUM(big)->as.heap.digits = ds;
             FL_UNSET_RAW(big, BIGNUM_EMBED_FLAG);
-	}
+        }
     }
     else {
-	if (len <= BIGNUM_EMBED_LEN_MAX) {
-	    ds = RBIGNUM(big)->as.heap.digits;
+        if (len <= BIGNUM_EMBED_LEN_MAX) {
+            ds = RBIGNUM(big)->as.heap.digits;
             FL_SET_RAW(big, BIGNUM_EMBED_FLAG);
-	    BIGNUM_SET_LEN(big, len);
+            BIGNUM_SET_LEN(big, len);
             (void)VALGRIND_MAKE_MEM_UNDEFINED((void*)RBIGNUM(big)->as.ary, sizeof(RBIGNUM(big)->as.ary));
-	    if (ds) {
-		MEMCPY(RBIGNUM(big)->as.ary, ds, BDIGIT, len);
-		xfree(ds);
-	    }
-	}
-	else {
-	    if (BIGNUM_LEN(big) == 0) {
-		RBIGNUM(big)->as.heap.digits = ALLOC_N(BDIGIT, len);
-	    }
-	    else {
-		REALLOC_N(RBIGNUM(big)->as.heap.digits, BDIGIT, len);
-	    }
-	}
+            if (ds) {
+                MEMCPY(RBIGNUM(big)->as.ary, ds, BDIGIT, len);
+                xfree(ds);
+            }
+        }
+        else {
+            if (BIGNUM_LEN(big) == 0) {
+                RBIGNUM(big)->as.heap.digits = ALLOC_N(BDIGIT, len);
+            }
+            else {
+                REALLOC_N(RBIGNUM(big)->as.heap.digits, BDIGIT, len);
+            }
+        }
     }
 }
 
@@ -3077,7 +3095,7 @@ abs2twocomp(VALUE *xp, long *n_ret)
         MEMCPY(BDIGITS(z), ds, BDIGIT, n);
         bary_2comp(BDIGITS(z), n);
         hibits = BDIGMAX;
-	*xp = z;
+        *xp = z;
     }
     *n_ret = n;
     return hibits;
@@ -3101,7 +3119,7 @@ bigtrunc(VALUE x)
     if (len == 0) return x;
     while (--len && !ds[len]);
     if (BIGNUM_LEN(x) > len+1) {
-	rb_big_resize(x, len+1);
+        rb_big_resize(x, len+1);
     }
     return x;
 }
@@ -3154,7 +3172,7 @@ static VALUE
 bignorm(VALUE x)
 {
     if (RB_BIGNUM_TYPE_P(x)) {
-	x = bigfixize(x);
+        x = bigfixize(x);
     }
     return x;
 }
@@ -3176,8 +3194,8 @@ rb_uint2big(uintptr_t n)
     digits[0] = n;
 #else
     for (i = 0; i < bdigit_roomof(SIZEOF_VALUE); i++) {
-	digits[i] = BIGLO(n);
-	n = BIGDN(n);
+        digits[i] = BIGLO(n);
+        n = BIGDN(n);
     }
 #endif
 
@@ -3196,14 +3214,14 @@ rb_int2big(intptr_t n)
 
     if (n < 0) {
         u = 1 + (VALUE)(-(n + 1)); /* u = -n avoiding overflow */
-	neg = 1;
+        neg = 1;
     }
     else {
         u = n;
     }
     big = rb_uint2big(u);
     if (neg) {
-	BIGNUM_SET_NEGATIVE_SIGN(big);
+        BIGNUM_SET_NEGATIVE_SIGN(big);
     }
     return big;
 }
@@ -3362,7 +3380,7 @@ absint_numwords_generic(size_t numbytes, int nlz_bits_in_msbyte, size_t word_num
 
     if (sign == 2) {
 #if defined __GNUC__ && (__GNUC__ == 4 && __GNUC_MINOR__ == 4)
-	*nlz_bits_ret = 0;
+        *nlz_bits_ret = 0;
 #endif
         return (size_t)-1;
     }
@@ -3682,7 +3700,7 @@ rb_integer_unpack(const void *words, size_t numwords, size_t wordsize, size_t na
         }
         else if (num_bdigits == numberof(fixbuf)) {
             val = bignew((long)num_bdigits+1, 0);
-	    MEMCPY(BDIGITS(val), fixbuf, BDIGIT, num_bdigits);
+            MEMCPY(BDIGITS(val), fixbuf, BDIGIT, num_bdigits);
             BDIGITS(val)[num_bdigits++] = 1;
         }
         else {
@@ -3694,9 +3712,9 @@ rb_integer_unpack(const void *words, size_t numwords, size_t wordsize, size_t na
         BDIGIT_DBL u = fixbuf[0] + BIGUP(fixbuf[1]);
         if (u == 0)
             return LONG2FIX(0);
-	if (0 < sign && POSFIXABLE(u))
+        if (0 < sign && POSFIXABLE(u))
             return LONG2FIX((long)u);
-	if (sign < 0 && BDIGIT_MSB(fixbuf[1]) == 0 &&
+        if (sign < 0 && BDIGIT_MSB(fixbuf[1]) == 0 &&
                 NEGFIXABLE(-(BDIGIT_DBL_SIGNED)u))
             return LONG2FIX((long)-(BDIGIT_DBL_SIGNED)u);
         val = bignew((long)num_bdigits, 0 <= sign);
@@ -3748,41 +3766,41 @@ str2big_scan_digits(const char *s, const char *str, int base, int badcheck, size
     int c;
 
     if (!len) {
-	*num_digits_p = 0;
-	*len_p = 0;
-	return TRUE;
+        *num_digits_p = 0;
+        *len_p = 0;
+        return TRUE;
     }
 
     if (badcheck && *str == '_') return FALSE;
 
     while ((c = *str++) != 0) {
-	if (c == '_') {
-	    if (nondigit) {
+        if (c == '_') {
+            if (nondigit) {
                 if (badcheck) return FALSE;
-		break;
-	    }
-	    nondigit = (char) c;
-	}
-	else if ((c = conv_digit(c)) < 0 || c >= base) {
-	    break;
-	}
-	else {
-	    nondigit = 0;
-	    num_digits++;
-	    digits_end = str;
-	}
-	if (len > 0 && !--len) break;
+                break;
+            }
+            nondigit = (char) c;
+        }
+        else if ((c = conv_digit(c)) < 0 || c >= base) {
+            break;
+        }
+        else {
+            nondigit = 0;
+            num_digits++;
+            digits_end = str;
+        }
+        if (len > 0 && !--len) break;
     }
     if (badcheck && nondigit) return FALSE;
     if (badcheck && len) {
-	str--;
-	while (*str && ISSPACE(*str)) {
-	    str++;
-	    if (len > 0 && !--len) break;
-	}
-	if (len && *str) {
-	    return FALSE;
-	}
+        str--;
+        while (*str && ISSPACE(*str)) {
+            str++;
+            if (len > 0 && !--len) break;
+        }
+        if (len && *str) {
+            return FALSE;
+        }
     }
     *num_digits_p = num_digits;
     *len_p = digits_end - digits_start;
@@ -3957,7 +3975,7 @@ str2big_karatsuba(
     return z;
 }
 
-#ifdef USE_GMP
+#if USE_GMP
 static VALUE
 str2big_gmp(
     int sign,
@@ -4024,8 +4042,8 @@ rb_cstr_to_inum(const char *str, int base, int badcheck)
     char *end;
     VALUE ret = rb_cstr_parse_inum(str, -1, (badcheck ? NULL : &end), base);
     if (NIL_P(ret)) {
-	if (badcheck) rb_invalid_str(str, "Integer()");
-	ret = INT2FIX(0);
+        if (badcheck) rb_invalid_str(str, "Integer()");
+        ret = INT2FIX(0);
     }
     return ret;
 }
@@ -4049,7 +4067,7 @@ rb_cstr_to_inum(const char *str, int base, int badcheck)
 
 VALUE
 rb_int_parse_cstr(const char *str, ssize_t len, char **endp, size_t *ndigits,
-		  int base, int flags)
+                  int base, int flags)
 {
     const char *const s = str;
     char sign = 1;
@@ -4066,82 +4084,82 @@ rb_int_parse_cstr(const char *str, ssize_t len, char **endp, size_t *ndigits,
     const int badcheck = !endp;
 
 #define ADV(n) do {\
-	if (len > 0 && len <= (n)) goto bad; \
-	str += (n); \
-	len -= (n); \
+        if (len > 0 && len <= (n)) goto bad; \
+        str += (n); \
+        len -= (n); \
     } while (0)
 #define ASSERT_LEN() do {\
-	assert(len != 0); \
-	if (len0 >= 0) assert(s + len0 == str + len); \
+        assert(len != 0); \
+        if (len0 >= 0) assert(s + len0 == str + len); \
     } while (0)
 
     if (!str) {
         goto bad;
     }
     if (len && (flags & RB_INT_PARSE_SIGN)) {
-	while (ISSPACE(*str)) ADV(1);
+        while (ISSPACE(*str)) ADV(1);
 
-	if (str[0] == '+') {
-	    ADV(1);
-	}
-	else if (str[0] == '-') {
-	    ADV(1);
-	    sign = 0;
-	}
-	ASSERT_LEN();
+        if (str[0] == '+') {
+            ADV(1);
+        }
+        else if (str[0] == '-') {
+            ADV(1);
+            sign = 0;
+        }
+        ASSERT_LEN();
     }
     if (base <= 0) {
-	if (str[0] == '0' && len > 1) {
-	    switch (str[1]) {
-	      case 'x': case 'X':
-		base = 16;
-		ADV(2);
-		break;
-	      case 'b': case 'B':
-		base = 2;
-		ADV(2);
-		break;
-	      case 'o': case 'O':
-		base = 8;
-		ADV(2);
-		break;
-	      case 'd': case 'D':
-		base = 10;
-		ADV(2);
-		break;
-	      default:
-		base = 8;
-	    }
-	}
-	else if (base < -1) {
-	    base = -base;
-	}
-	else {
-	    base = 10;
-	}
+        if (str[0] == '0' && len > 1) {
+            switch (str[1]) {
+              case 'x': case 'X':
+                base = 16;
+                ADV(2);
+                break;
+              case 'b': case 'B':
+                base = 2;
+                ADV(2);
+                break;
+              case 'o': case 'O':
+                base = 8;
+                ADV(2);
+                break;
+              case 'd': case 'D':
+                base = 10;
+                ADV(2);
+                break;
+              default:
+                base = 8;
+            }
+        }
+        else if (base < -1) {
+            base = -base;
+        }
+        else {
+            base = 10;
+        }
     }
     else if (len == 1 || !(flags & RB_INT_PARSE_PREFIX)) {
-	/* no prefix */
+        /* no prefix */
     }
     else if (base == 2) {
-	if (str[0] == '0' && (str[1] == 'b'||str[1] == 'B')) {
-	    ADV(2);
-	}
+        if (str[0] == '0' && (str[1] == 'b'||str[1] == 'B')) {
+            ADV(2);
+        }
     }
     else if (base == 8) {
-	if (str[0] == '0' && (str[1] == 'o'||str[1] == 'O')) {
-	    ADV(2);
-	}
+        if (str[0] == '0' && (str[1] == 'o'||str[1] == 'O')) {
+            ADV(2);
+        }
     }
     else if (base == 10) {
-	if (str[0] == '0' && (str[1] == 'd'||str[1] == 'D')) {
-	    ADV(2);
-	}
+        if (str[0] == '0' && (str[1] == 'd'||str[1] == 'D')) {
+            ADV(2);
+        }
     }
     else if (base == 16) {
-	if (str[0] == '0' && (str[1] == 'x'||str[1] == 'X')) {
-	    ADV(2);
-	}
+        if (str[0] == '0' && (str[1] == 'x'||str[1] == 'X')) {
+            ADV(2);
+        }
     }
     if (!valid_radix_p(base)) {
         invalid_radix(base);
@@ -4149,80 +4167,79 @@ rb_int_parse_cstr(const char *str, ssize_t len, char **endp, size_t *ndigits,
     if (!len) goto bad;
     num_digits = str - s;
     if (*str == '0' && len != 1) { /* squeeze preceding 0s */
-	int us = 0;
-	const char *end = len < 0 ? NULL : str + len;
-	++num_digits;
-	while ((c = *++str) == '0' ||
-	       ((flags & RB_INT_PARSE_UNDERSCORE) && c == '_')) {
-	    if (c == '_') {
-		if (++us >= 2)
-		    break;
-	    }
-	    else {
-		++num_digits;
-		us = 0;
-	    }
-	    if (str == end) break;
-	}
-	if (!c || ISSPACE(c)) --str;
-	if (end) len = end - str;
-	ASSERT_LEN();
+        int us = 0;
+        const char *end = len < 0 ? NULL : str + len;
+        ++num_digits;
+        while ((c = *++str) == '0' ||
+               ((flags & RB_INT_PARSE_UNDERSCORE) && c == '_')) {
+            if (c == '_') {
+                if (++us >= 2)
+                    break;
+            }
+            else {
+                ++num_digits;
+                us = 0;
+            }
+            if (str == end) break;
+        }
+        if (!c || ISSPACE(c)) --str;
+        if (end) len = end - str;
     }
     c = *str;
     c = conv_digit(c);
     if (c < 0 || c >= base) {
-	if (!badcheck && num_digits) z = INT2FIX(0);
-	goto bad;
+        if (!badcheck && num_digits) z = INT2FIX(0);
+        goto bad;
     }
 
     if (ndigits) *ndigits = num_digits;
     val = ruby_scan_digits(str, len, base, &num_digits, &ov);
     if (!ov) {
-	const char *end = &str[num_digits];
-	if (num_digits > 0 && *end == '_' && (flags & RB_INT_PARSE_UNDERSCORE))
-	    goto bigparse;
-	if (endp) *endp = (char *)end;
-	if (ndigits) *ndigits += num_digits;
-	if (badcheck) {
-	    if (num_digits == 0) return Qnil; /* no number */
-	    while (len < 0 ? *end : end < str + len) {
-		if (!ISSPACE(*end)) return Qnil; /* trailing garbage */
-		end++;
-	    }
-	}
-
-	if (POSFIXABLE(val)) {
-	    if (sign) return LONG2FIX(val);
-	    else {
-		long result = -(long)val;
-		return LONG2FIX(result);
-	    }
-	}
-	else {
-	    VALUE big = rb_uint2big(val);
-	    BIGNUM_SET_SIGN(big, sign);
-	    return bignorm(big);
-	}
+        const char *end = &str[num_digits];
+        if (num_digits > 0 && *end == '_' && (flags & RB_INT_PARSE_UNDERSCORE))
+            goto bigparse;
+        if (endp) *endp = (char *)end;
+        if (ndigits) *ndigits += num_digits;
+        if (badcheck) {
+            if (num_digits == 0) return Qnil; /* no number */
+            while (len < 0 ? *end : end < str + len) {
+                if (!ISSPACE(*end)) return Qnil; /* trailing garbage */
+                end++;
+            }
+        }
+
+        if (POSFIXABLE(val)) {
+            if (sign) return LONG2FIX(val);
+            else {
+                long result = -(long)val;
+                return LONG2FIX(result);
+            }
+        }
+        else {
+            VALUE big = rb_uint2big(val);
+            BIGNUM_SET_SIGN(big, sign);
+            return bignorm(big);
+        }
     }
 
   bigparse:
     digits_start = str;
     if (!str2big_scan_digits(s, str, base, badcheck, &num_digits, &len))
-	goto bad;
+        goto bad;
     if (endp) *endp = (char *)(str + len);
     if (ndigits) *ndigits += num_digits;
     digits_end = digits_start + len;
 
     if (POW2_P(base)) {
         z = str2big_poweroftwo(sign, digits_start, digits_end, num_digits,
-			       bit_length(base-1));
+                               bit_length(base-1));
     }
     else {
         int digits_per_bdigits_dbl;
         maxpow_in_bdigit_dbl(base, &digits_per_bdigits_dbl);
         num_bdigits = roomof(num_digits, digits_per_bdigits_dbl)*2;
 
-#ifdef USE_GMP
+#if USE_GMP
         if (GMP_STR2BIG_DIGITS < num_bdigits) {
             z = str2big_gmp(sign, digits_start, digits_end, num_digits,
                     num_bdigits, base);
@@ -4251,7 +4268,7 @@ static VALUE
 rb_cstr_parse_inum(const char *str, ssize_t len, char **endp, int base)
 {
     return rb_int_parse_cstr(str, len, endp, NULL, base,
-			     RB_INT_PARSE_DEFAULT);
+                             RB_INT_PARSE_DEFAULT);
 }
 
 VALUE
@@ -4300,14 +4317,14 @@ rb_str2big_poweroftwo(VALUE arg, int base, int badcheck)
     s = str = StringValueCStr(arg);
     len = RSTRING_LEN(arg);
     if (*str == '-') {
-	len--;
+        len--;
         str++;
         positive_p = 0;
     }
 
     digits_start = str;
     if (!str2big_scan_digits(s, str, base, badcheck, &num_digits, &len))
-	invalid_integer(arg);
+        invalid_integer(arg);
     digits_end = digits_start + len;
 
     z = str2big_poweroftwo(positive_p, digits_start, digits_end, num_digits,
@@ -4339,14 +4356,14 @@ rb_str2big_normal(VALUE arg, int base, int badcheck)
     s = str = StringValuePtr(arg);
     len = RSTRING_LEN(arg);
     if (len > 0 && *str == '-') {
-	len--;
+        len--;
         str++;
         positive_p = 0;
     }
 
     digits_start = str;
     if (!str2big_scan_digits(s, str, base, badcheck, &num_digits, &len))
-	invalid_integer(arg);
+        invalid_integer(arg);
     digits_end = digits_start + len;
 
     maxpow_in_bdigit_dbl(base, &digits_per_bdigits_dbl);
@@ -4381,14 +4398,14 @@ rb_str2big_karatsuba(VALUE arg, int base, int badcheck)
     s = str = StringValuePtr(arg);
     len = RSTRING_LEN(arg);
     if (len > 0 && *str == '-') {
-	len--;
+        len--;
         str++;
         positive_p = 0;
     }
 
     digits_start = str;
     if (!str2big_scan_digits(s, str, base, badcheck, &num_digits, &len))
-	invalid_integer(arg);
+        invalid_integer(arg);
     digits_end = digits_start + len;
 
     maxpow_in_bdigit_dbl(base, &digits_per_bdigits_dbl);
@@ -4402,7 +4419,7 @@ rb_str2big_karatsuba(VALUE arg, int base, int badcheck)
     return bignorm(z);
 }
 
-#ifdef USE_GMP
+#if USE_GMP
 VALUE
 rb_str2big_gmp(VALUE arg, int base, int badcheck)
 {
@@ -4424,14 +4441,14 @@ rb_str2big_gmp(VALUE arg, int base, int badcheck)
     s = str = StringValuePtr(arg);
     len = RSTRING_LEN(arg);
     if (len > 0 && *str == '-') {
-	len--;
+        len--;
         str++;
         positive_p = 0;
     }
 
     digits_start = str;
     if (!str2big_scan_digits(s, str, base, badcheck, &num_digits, &len))
-	invalid_integer(arg);
+        invalid_integer(arg);
     digits_end = digits_start + len;
 
     maxpow_in_bdigit_dbl(base, &digits_per_bdigits_dbl);
@@ -4458,8 +4475,8 @@ rb_ull2big(unsigned LONG_LONG n)
     digits[0] = n;
 #else
     for (i = 0; i < bdigit_roomof(SIZEOF_LONG_LONG); i++) {
-	digits[i] = BIGLO(n);
-	n = BIGDN(n);
+        digits[i] = BIGLO(n);
+        n = BIGDN(n);
     }
 #endif
 
@@ -4478,14 +4495,14 @@ rb_ll2big(LONG_LONG n)
 
     if (n < 0) {
         u = 1 + (unsigned LONG_LONG)(-(n + 1)); /* u = -n avoiding overflow */
-	neg = 1;
+        neg = 1;
     }
     else {
         u = n;
     }
     big = rb_ull2big(u);
     if (neg) {
-	BIGNUM_SET_NEGATIVE_SIGN(big);
+        BIGNUM_SET_NEGATIVE_SIGN(big);
     }
     return big;
 }
@@ -4515,7 +4532,7 @@ rb_uint128t2big(uint128_t n)
     BDIGIT *digits = BDIGITS(big);
 
     for (i = 0; i < bdigit_roomof(SIZEOF_INT128_T); i++) {
-	digits[i] = BIGLO(RSHIFT(n ,BITSPERDIG*i));
+        digits[i] = BIGLO(RSHIFT(n ,BITSPERDIG*i));
     }
 
     i = bdigit_roomof(SIZEOF_INT128_T);
@@ -4533,14 +4550,14 @@ rb_int128t2big(int128_t n)
 
     if (n < 0) {
         u = 1 + (uint128_t)(-(n + 1)); /* u = -n avoiding overflow */
-	neg = 1;
+        neg = 1;
     }
     else {
         u = n;
     }
     big = rb_uint128t2big(u);
     if (neg) {
-	BIGNUM_SET_NEGATIVE_SIGN(big);
+        BIGNUM_SET_NEGATIVE_SIGN(big);
     }
     return big;
 }
@@ -4569,11 +4586,14 @@ big_shift3(VALUE x, int lshift_p, size_t shift_numdigits, int shift_numbits)
 
     if (lshift_p) {
         if (LONG_MAX < shift_numdigits) {
-            rb_raise(rb_eArgError, "too big number");
+          too_big:
+            rb_raise(rb_eRangeError, "shift width too big");
         }
         s1 = shift_numdigits;
         s2 = shift_numbits;
+        if ((size_t)s1 != shift_numdigits) goto too_big;
         xn = BIGNUM_LEN(x);
+        if (LONG_MAX/SIZEOF_BDIGIT <= xn+s1) goto too_big;
         z = bignew(xn+s1+1, BIGNUM_SIGN(x));
         zds = BDIGITS(z);
         BDIGITS_ZERO(zds, s1);
@@ -4703,7 +4723,7 @@ power_cache_get_power(int base, int power_level, size_t *numdigits_ret)
         rb_obj_hide(power);
         base36_power_cache[base - 2][power_level] = power;
         base36_numdigits_cache[base - 2][power_level] = numdigits;
-	rb_gc_register_mark_object(power);
+        rb_gc_register_mark_object(power);
     }
     if (numdigits_ret)
         *numdigits_ret = base36_numdigits_cache[base - 2][power_level];
@@ -4754,7 +4774,7 @@ big2str_2bdigits(struct big2str_struct *b2s, BDIGIT *xds, size_t xn, size_t tail
         } while (num);
         len = sizeof(buf) - j;
         big2str_alloc(b2s, len + taillen);
-	MEMCPY(b2s->ptr, buf + j, char, len);
+        MEMCPY(b2s->ptr, buf + j, char, len);
     }
     else {
         p = b2s->ptr;
@@ -4771,7 +4791,7 @@ big2str_2bdigits(struct big2str_struct *b2s, BDIGIT *xds, size_t xn, size_t tail
 
 static void
 big2str_karatsuba(struct big2str_struct *b2s, BDIGIT *xds, size_t xn, size_t wn,
-		  int power_level, size_t taillen)
+                  int power_level, size_t taillen)
 {
     VALUE b;
     size_t half_numdigits, lower_numdigits;
@@ -4801,17 +4821,17 @@ big2str_karatsuba(struct big2str_struct *b2s, BDIGIT *xds, size_t xn, size_t wn,
      */
 
     if (xn == 0 || bary_zero_p(xds, xn)) {
-	if (b2s->ptr) {
+        if (b2s->ptr) {
             /* When x is zero, power_cache_get_power(base, power_level) should be cached already. */
             power_cache_get_power(b2s->base, power_level, &len);
-	    memset(b2s->ptr, '0', len);
+            memset(b2s->ptr, '0', len);
             b2s->ptr += len;
-	}
+        }
         return;
     }
 
     if (power_level == 0) {
-	big2str_2bdigits(b2s, xds, xn, taillen);
+        big2str_2bdigits(b2s, xds, xn, taillen);
         return;
     }
 
@@ -4839,7 +4859,7 @@ big2str_karatsuba(struct big2str_struct *b2s, BDIGIT *xds, size_t xn, size_t wn,
             memset(b2s->ptr, '0', len);
             b2s->ptr += len;
         }
-	big2str_2bdigits(b2s, xds, xn, taillen);
+        big2str_2bdigits(b2s, xds, xn, taillen);
     }
     else {
         BDIGIT *qds, *rds;
@@ -4943,11 +4963,11 @@ big2str_generic(VALUE x, int base)
     BARY_TRUNC(xds, xn);
 
     if (xn == 0) {
-	return rb_usascii_str_new2("0");
+        return rb_usascii_str_new2("0");
     }
 
     if (!valid_radix_p(base))
-	invalid_radix(base);
+        invalid_radix(base);
 
     if (xn >= LONG_MAX/BITSPERDIG) {
         rb_raise(rb_eRangeError, "bignum too big to convert into `string'");
@@ -4984,7 +5004,7 @@ big2str_generic(VALUE x, int base)
     b2s_data.ptr = NULL;
 
     if (power_level == 0) {
-	big2str_2bdigits(&b2s_data, xds, xn, 0);
+        big2str_2bdigits(&b2s_data, xds, xn, 0);
     }
     else {
         VALUE tmpw = 0;
@@ -4993,7 +5013,7 @@ big2str_generic(VALUE x, int base)
         wn = power_level * BIGDIVREM_EXTRA_WORDS + BIGNUM_LEN(power);
         wds = ALLOCV_N(BDIGIT, tmpw, xn + wn);
         MEMCPY(wds, xds, BDIGIT, xn);
-	big2str_karatsuba(&b2s_data, wds, xn, wn, power_level, 0);
+        big2str_karatsuba(&b2s_data, wds, xn, wn, power_level, 0);
         if (tmpw)
             ALLOCV_END(tmpw);
     }
@@ -5012,7 +5032,7 @@ rb_big2str_generic(VALUE x, int base)
     return big2str_generic(x, base);
 }
 
-#ifdef USE_GMP
+#if USE_GMP
 static VALUE
 big2str_gmp(VALUE x, int base)
 {
@@ -5059,7 +5079,7 @@ rb_big2str1(VALUE x, int base)
     size_t xn;
 
     if (FIXNUM_P(x)) {
-	return rb_fix2str(x, base);
+        return rb_fix2str(x, base);
     }
 
     bigtrunc(x);
@@ -5068,11 +5088,11 @@ rb_big2str1(VALUE x, int base)
     BARY_TRUNC(xds, xn);
 
     if (xn == 0) {
-	return rb_usascii_str_new2("0");
+        return rb_usascii_str_new2("0");
     }
 
     if (!valid_radix_p(base))
-	invalid_radix(base);
+        invalid_radix(base);
 
     if (xn >= LONG_MAX/BITSPERDIG) {
         rb_raise(rb_eRangeError, "bignum too big to convert into `string'");
@@ -5083,7 +5103,7 @@ rb_big2str1(VALUE x, int base)
         return big2str_base_poweroftwo(x, base);
     }
 
-#ifdef USE_GMP
+#if USE_GMP
     if (GMP_BIG2STR_DIGITS < xn) {
         return big2str_gmp(x, base);
     }
@@ -5119,7 +5139,7 @@ big2ulong(VALUE x, const char *type)
 #else
     num = 0;
     for (i = 0; i < len; i++) {
-	num <<= BITSPERDIG;
+        num <<= BITSPERDIG;
         num += (unsigned long)ds[len - i - 1]; /* overflow is already checked */
     }
 #endif
@@ -5172,13 +5192,13 @@ big2ull(VALUE x, const char *type)
     if (len == 0)
         return 0;
     if (BIGSIZE(x) > SIZEOF_LONG_LONG)
-	rb_raise(rb_eRangeError, "bignum too big to convert into `%s'", type);
+        rb_raise(rb_eRangeError, "bignum too big to convert into `%s'", type);
 #if SIZEOF_LONG_LONG <= SIZEOF_BDIGIT
     num = (unsigned LONG_LONG)ds[0];
 #else
     num = 0;
     for (i = 0; i < len; i++) {
-	num = BIGUP(num);
+        num = BIGUP(num);
         num += ds[len - i - 1];
     }
 #endif
@@ -5228,23 +5248,23 @@ dbl2big(double d)
     double u = (d < 0)?-d:d;
 
     if (isinf(d)) {
-	rb_raise(rb_eFloatDomainError, d < 0 ? "-Infinity" : "Infinity");
+        rb_raise(rb_eFloatDomainError, d < 0 ? "-Infinity" : "Infinity");
     }
     if (isnan(d)) {
-	rb_raise(rb_eFloatDomainError, "NaN");
+        rb_raise(rb_eFloatDomainError, "NaN");
     }
 
     while (1.0 <= u) {
-	u /= (double)(BIGRAD);
-	i++;
+        u /= (double)(BIGRAD);
+        i++;
     }
     z = bignew(i, d>=0);
     digits = BDIGITS(z);
     while (i--) {
-	u *= BIGRAD;
-	c = (BDIGIT)u;
-	u -= c;
-	digits[i] = c;
+        u *= BIGRAD;
+        c = (BDIGIT)u;
+        u -= c;
+        digits[i] = c;
     }
 
     return z;
@@ -5264,28 +5284,28 @@ big2dbl(VALUE x)
     BDIGIT *ds = BDIGITS(x), dl;
 
     if (i) {
-	bits = i * BITSPERDIG - nlz(ds[i-1]);
-	if (bits > DBL_MANT_DIG+DBL_MAX_EXP) {
-	    d = HUGE_VAL;
-	}
-	else {
-	    if (bits > DBL_MANT_DIG+1)
-		lo = (bits -= DBL_MANT_DIG+1) / BITSPERDIG;
-	    else
-		bits = 0;
-	    while (--i > lo) {
-		d = ds[i] + BIGRAD*d;
-	    }
-	    dl = ds[i];
-	    if (bits && (dl & ((BDIGIT)1 << (bits %= BITSPERDIG)))) {
-		int carry = (dl & ~(BDIGMAX << bits)) != 0;
-		if (!carry) {
-		    while (i-- > 0) {
-			carry = ds[i] != 0;
-			if (carry) break;
-		    }
-		}
-		if (carry) {
+        bits = i * BITSPERDIG - nlz(ds[i-1]);
+        if (bits > DBL_MANT_DIG+DBL_MAX_EXP) {
+            d = HUGE_VAL;
+        }
+        else {
+            if (bits > DBL_MANT_DIG+1)
+                lo = (bits -= DBL_MANT_DIG+1) / BITSPERDIG;
+            else
+                bits = 0;
+            while (--i > lo) {
+                d = ds[i] + BIGRAD*d;
+            }
+            dl = ds[i];
+            if (bits && (dl & ((BDIGIT)1 << (bits %= BITSPERDIG)))) {
+                int carry = (dl & ~(BDIGMAX << bits)) != 0;
+                if (!carry) {
+                    while (i-- > 0) {
+                        carry = ds[i] != 0;
+                        if (carry) break;
+                    }
+                }
+                if (carry) {
                     BDIGIT mask = BDIGMAX;
                     BDIGIT bit = 1;
                     mask <<= bits;
@@ -5293,19 +5313,19 @@ big2dbl(VALUE x)
                     dl &= mask;
                     dl += bit;
                     dl = BIGLO(dl);
-		    if (!dl) d += 1;
-		}
-	    }
-	    d = dl + BIGRAD*d;
-	    if (lo) {
-		if (lo > INT_MAX / BITSPERDIG)
-		    d = HUGE_VAL;
-		else if (lo < INT_MIN / BITSPERDIG)
-		    d = 0.0;
-		else
-		    d = ldexp(d, (int)(lo * BITSPERDIG));
-	    }
-	}
+                    if (!dl) d += 1;
+                }
+            }
+            d = dl + BIGRAD*d;
+            if (lo) {
+                if (lo > INT_MAX / BITSPERDIG)
+                    d = HUGE_VAL;
+                else if (lo < INT_MIN / BITSPERDIG)
+                    d = 0.0;
+                else
+                    d = ldexp(d, (int)(lo * BITSPERDIG));
+            }
+        }
     }
     if (BIGNUM_NEGATIVE_P(x)) d = -d;
     return d;
@@ -5317,11 +5337,11 @@ rb_big2dbl(VALUE x)
     double d = big2dbl(x);
 
     if (isinf(d)) {
-	rb_warning("Integer out of Float range");
-	if (d < 0.0)
-	    d = -HUGE_VAL;
-	else
-	    d = HUGE_VAL;
+        rb_warning("Integer out of Float range");
+        if (d < 0.0)
+            d = -HUGE_VAL;
+        else
+            d = HUGE_VAL;
     }
     return d;
 }
@@ -5418,26 +5438,26 @@ VALUE
 rb_big_cmp(VALUE x, VALUE y)
 {
     if (FIXNUM_P(y)) {
-	x = bigfixize(x);
+        x = bigfixize(x);
         if (FIXNUM_P(x)) {
-	    /* SIGNED_VALUE and Fixnum have same sign-bits, same
-	     * order */
-	    SIGNED_VALUE sx = (SIGNED_VALUE)x, sy = (SIGNED_VALUE)y;
-	    if (sx < sy) return INT2FIX(-1);
-	    return INT2FIX(sx > sy);
+            /* SIGNED_VALUE and Fixnum have same sign-bits, same
+             * order */
+            SIGNED_VALUE sx = (SIGNED_VALUE)x, sy = (SIGNED_VALUE)y;
+            if (sx < sy) return INT2FIX(-1);
+            return INT2FIX(sx > sy);
         }
     }
     else if (RB_BIGNUM_TYPE_P(y)) {
-	if (BIGNUM_SIGN(x) == BIGNUM_SIGN(y)) {
-	    int cmp = bary_cmp(BDIGITS(x), BIGNUM_LEN(x), BDIGITS(y), BIGNUM_LEN(y));
-	    return INT2FIX(BIGNUM_SIGN(x) ? cmp : -cmp);
-	}
+        if (BIGNUM_SIGN(x) == BIGNUM_SIGN(y)) {
+            int cmp = bary_cmp(BDIGITS(x), BIGNUM_LEN(x), BDIGITS(y), BIGNUM_LEN(y));
+            return INT2FIX(BIGNUM_SIGN(x) ? cmp : -cmp);
+        }
     }
     else if (RB_FLOAT_TYPE_P(y)) {
         return rb_integer_float_cmp(x, y);
     }
     else {
-	return rb_num_coerce_cmp(x, y, idCmp);
+        return rb_num_coerce_cmp(x, y, idCmp);
     }
     return INT2FIX(BIGNUM_SIGN(x) ? 1 : -1);
 }
@@ -5456,30 +5476,30 @@ big_op(VALUE x, VALUE y, enum big_op_t op)
     int n;
 
     if (RB_INTEGER_TYPE_P(y)) {
-	rel = rb_big_cmp(x, y);
+        rel = rb_big_cmp(x, y);
     }
     else if (RB_FLOAT_TYPE_P(y)) {
         rel = rb_integer_float_cmp(x, y);
     }
     else {
-	ID id = 0;
-	switch (op) {
-	  case big_op_gt: id = '>'; break;
-	  case big_op_ge: id = idGE; break;
-	  case big_op_lt: id = '<'; break;
-	  case big_op_le: id = idLE; break;
-	}
-	return rb_num_coerce_relop(x, y, id);
+        ID id = 0;
+        switch (op) {
+          case big_op_gt: id = '>'; break;
+          case big_op_ge: id = idGE; break;
+          case big_op_lt: id = '<'; break;
+          case big_op_le: id = idLE; break;
+        }
+        return rb_num_coerce_relop(x, y, id);
     }
 
     if (NIL_P(rel)) return Qfalse;
     n = FIX2INT(rel);
 
     switch (op) {
-	case big_op_gt: return RBOOL(n >  0);
-	case big_op_ge: return RBOOL(n >= 0);
-	case big_op_lt: return RBOOL(n <  0);
-	case big_op_le: return RBOOL(n <= 0);
+        case big_op_gt: return RBOOL(n >  0);
+        case big_op_ge: return RBOOL(n >= 0);
+        case big_op_lt: return RBOOL(n <  0);
+        case big_op_le: return RBOOL(n <= 0);
     }
     return Qundef;
 }
@@ -5523,7 +5543,7 @@ VALUE
 rb_big_eq(VALUE x, VALUE y)
 {
     if (FIXNUM_P(y)) {
-	return RBOOL(bignorm(x) == y);
+        return RBOOL(bignorm(x) == y);
     }
     else if (RB_BIGNUM_TYPE_P(y)) {
     }
@@ -5531,7 +5551,7 @@ rb_big_eq(VALUE x, VALUE y)
         return rb_integer_float_eq(x, y);
     }
     else {
-	return rb_equal(y, x);
+        return rb_equal(y, x);
     }
     if (BIGNUM_SIGN(x) != BIGNUM_SIGN(y)) return Qfalse;
     if (BIGNUM_LEN(x) != BIGNUM_LEN(y)) return Qfalse;
@@ -5638,10 +5658,10 @@ bigsub_int(VALUE x, long y0)
     assert(xn == zn);
     num = (BDIGIT_DBL_SIGNED)xds[0] - y;
     if (xn == 1 && num < 0) {
-	BIGNUM_NEGATE(z);
-	zds[0] = (BDIGIT)-num;
-	RB_GC_GUARD(x);
-	return bignorm(z);
+        BIGNUM_NEGATE(z);
+        zds[0] = (BDIGIT)-num;
+        RB_GC_GUARD(x);
+        return bignorm(z);
     }
     zds[0] = BIGLO(num);
     num = BIGDN(num);
@@ -5653,10 +5673,10 @@ bigsub_int(VALUE x, long y0)
     num = 0;
     for (i=0; i < xn; i++) {
         if (y == 0) goto y_is_zero_x;
-	num += (BDIGIT_DBL_SIGNED)xds[i] - BIGLO(y);
-	zds[i] = BIGLO(num);
-	num = BIGDN(num);
-	y = BIGDN(y);
+        num += (BDIGIT_DBL_SIGNED)xds[i] - BIGLO(y);
+        zds[i] = BIGLO(num);
+        num = BIGDN(num);
+        y = BIGDN(y);
     }
     for (; i < zn; i++) {
         if (y == 0) goto y_is_zero_z;
@@ -5671,9 +5691,9 @@ bigsub_int(VALUE x, long y0)
     for (; i < xn; i++) {
       y_is_zero_x:
         if (num == 0) goto num_is_zero_x;
-	num += xds[i];
-	zds[i] = BIGLO(num);
-	num = BIGDN(num);
+        num += xds[i];
+        zds[i] = BIGLO(num);
+        num = BIGDN(num);
     }
 #if SIZEOF_BDIGIT < SIZEOF_LONG
     for (; i < zn; i++) {
@@ -5687,7 +5707,7 @@ bigsub_int(VALUE x, long y0)
 
     for (; i < xn; i++) {
       num_is_zero_x:
-	zds[i] = xds[i];
+        zds[i] = xds[i];
     }
 #if SIZEOF_BDIGIT < SIZEOF_LONG
     for (; i < zn; i++) {
@@ -5701,7 +5721,7 @@ bigsub_int(VALUE x, long y0)
     assert(num == 0 || num == -1);
     if (num < 0) {
         get2comp(z);
-	BIGNUM_NEGATE(z);
+        BIGNUM_NEGATE(z);
     }
     RB_GC_GUARD(x);
     return bignorm(z);
@@ -5744,17 +5764,17 @@ bigadd_int(VALUE x, long y)
     num = 0;
     for (i=0; i < xn; i++) {
         if (y == 0) goto y_is_zero_x;
-	num += (BDIGIT_DBL)xds[i] + BIGLO(y);
-	zds[i] = BIGLO(num);
-	num = BIGDN(num);
-	y = BIGDN(y);
+        num += (BDIGIT_DBL)xds[i] + BIGLO(y);
+        zds[i] = BIGLO(num);
+        num = BIGDN(num);
+        y = BIGDN(y);
     }
     for (; i < zn; i++) {
         if (y == 0) goto y_is_zero_z;
-	num += BIGLO(y);
-	zds[i] = BIGLO(num);
-	num = BIGDN(num);
-	y = BIGDN(y);
+        num += BIGLO(y);
+        zds[i] = BIGLO(num);
+        num = BIGDN(num);
+        y = BIGDN(y);
     }
     goto finish;
 
@@ -5763,25 +5783,25 @@ bigadd_int(VALUE x, long y)
     for (;i < xn; i++) {
       y_is_zero_x:
         if (num == 0) goto num_is_zero_x;
-	num += (BDIGIT_DBL)xds[i];
-	zds[i] = BIGLO(num);
-	num = BIGDN(num);
+        num += (BDIGIT_DBL)xds[i];
+        zds[i] = BIGLO(num);
+        num = BIGDN(num);
     }
     for (; i < zn; i++) {
       y_is_zero_z:
         if (num == 0) goto num_is_zero_z;
-	zds[i] = BIGLO(num);
-	num = BIGDN(num);
+        zds[i] = BIGLO(num);
+        num = BIGDN(num);
     }
     goto finish;
 
     for (;i < xn; i++) {
       num_is_zero_x:
-	zds[i] = xds[i];
+        zds[i] = xds[i];
     }
     for (; i < zn; i++) {
       num_is_zero_z:
-	zds[i] = 0;
+        zds[i] = 0;
     }
     goto finish;
 
@@ -5798,15 +5818,15 @@ bigadd(VALUE x, VALUE y, int sign)
 
     sign = (sign == BIGNUM_SIGN(y));
     if (BIGNUM_SIGN(x) != sign) {
-	if (sign) return bigsub(y, x);
-	return bigsub(x, y);
+        if (sign) return bigsub(y, x);
+        return bigsub(x, y);
     }
 
     if (BIGNUM_LEN(x) > BIGNUM_LEN(y)) {
-	len = BIGNUM_LEN(x) + 1;
+        len = BIGNUM_LEN(x) + 1;
     }
     else {
-	len = BIGNUM_LEN(y) + 1;
+        len = BIGNUM_LEN(y) + 1;
     }
     z = bignew(len, sign);
 
@@ -5823,26 +5843,26 @@ rb_big_plus(VALUE x, VALUE y)
     long n;
 
     if (FIXNUM_P(y)) {
-	n = FIX2LONG(y);
-	if ((n > 0) != BIGNUM_SIGN(x)) {
-	    if (n < 0) {
-		n = -n;
-	    }
-	    return bigsub_int(x, n);
-	}
-	if (n < 0) {
-	    n = -n;
-	}
-	return bigadd_int(x, n);
+        n = FIX2LONG(y);
+        if ((n > 0) != BIGNUM_SIGN(x)) {
+            if (n < 0) {
+                n = -n;
+            }
+            return bigsub_int(x, n);
+        }
+        if (n < 0) {
+            n = -n;
+        }
+        return bigadd_int(x, n);
     }
     else if (RB_BIGNUM_TYPE_P(y)) {
-	return bignorm(bigadd(x, y, 1));
+        return bignorm(bigadd(x, y, 1));
     }
     else if (RB_FLOAT_TYPE_P(y)) {
-	return DBL2NUM(rb_big2dbl(x) + RFLOAT_VALUE(y));
+        return DBL2NUM(rb_big2dbl(x) + RFLOAT_VALUE(y));
     }
     else {
-	return rb_num_coerce_bin(x, y, '+');
+        return rb_num_coerce_bin(x, y, '+');
     }
 }
 
@@ -5852,26 +5872,26 @@ rb_big_minus(VALUE x, VALUE y)
     long n;
 
     if (FIXNUM_P(y)) {
-	n = FIX2LONG(y);
-	if ((n > 0) != BIGNUM_SIGN(x)) {
-	    if (n < 0) {
-		n = -n;
-	    }
-	    return bigadd_int(x, n);
-	}
-	if (n < 0) {
-	    n = -n;
-	}
-	return bigsub_int(x, n);
+        n = FIX2LONG(y);
+        if ((n > 0) != BIGNUM_SIGN(x)) {
+            if (n < 0) {
+                n = -n;
+            }
+            return bigadd_int(x, n);
+        }
+        if (n < 0) {
+            n = -n;
+        }
+        return bigsub_int(x, n);
     }
     else if (RB_BIGNUM_TYPE_P(y)) {
-	return bignorm(bigadd(x, y, 0));
+        return bignorm(bigadd(x, y, 0));
     }
     else if (RB_FLOAT_TYPE_P(y)) {
-	return DBL2NUM(rb_big2dbl(x) - RFLOAT_VALUE(y));
+        return DBL2NUM(rb_big2dbl(x) - RFLOAT_VALUE(y));
     }
     else {
-	return rb_num_coerce_bin(x, y, '-');
+        return rb_num_coerce_bin(x, y, '-');
     }
 }
 
@@ -5930,15 +5950,15 @@ VALUE
 rb_big_mul(VALUE x, VALUE y)
 {
     if (FIXNUM_P(y)) {
-	y = rb_int2big(FIX2LONG(y));
+        y = rb_int2big(FIX2LONG(y));
     }
     else if (RB_BIGNUM_TYPE_P(y)) {
     }
     else if (RB_FLOAT_TYPE_P(y)) {
-	return DBL2NUM(rb_big2dbl(x) * RFLOAT_VALUE(y));
+        return DBL2NUM(rb_big2dbl(x) * RFLOAT_VALUE(y));
     }
     else {
-	return rb_num_coerce_bin(x, y, '*');
+        return rb_num_coerce_bin(x, y, '*');
     }
 
     return bignorm(bigmul0(x, y));
@@ -5965,21 +5985,21 @@ bigdivrem(VALUE x, VALUE y, volatile VALUE *divp, volatile VALUE *modp)
     BARY_TRUNC(xds, xn);
 
     if (xn < yn || (xn == yn && xds[xn - 1] < yds[yn - 1])) {
-	if (divp) *divp = rb_int2big(0);
-	if (modp) *modp = x;
-	return Qnil;
+        if (divp) *divp = rb_int2big(0);
+        if (modp) *modp = x;
+        return Qnil;
     }
     if (yn == 1) {
-	dd = yds[0];
-	z = bignew(xn, BIGNUM_SIGN(x)==BIGNUM_SIGN(y));
-	zds = BDIGITS(z);
+        dd = yds[0];
+        z = bignew(xn, BIGNUM_SIGN(x)==BIGNUM_SIGN(y));
+        zds = BDIGITS(z);
         dd = bigdivrem_single(zds, xds, xn, dd);
-	if (modp) {
-	    *modp = rb_uint2big((uintptr_t)dd);
-	    BIGNUM_SET_SIGN(*modp, BIGNUM_SIGN(x));
-	}
-	if (divp) *divp = z;
-	return Qnil;
+        if (modp) {
+            *modp = rb_uint2big((uintptr_t)dd);
+            BIGNUM_SET_SIGN(*modp, BIGNUM_SIGN(x));
+        }
+        if (divp) *divp = z;
+        return Qnil;
     }
     if (xn == 2 && yn == 2) {
         BDIGIT_DBL x0 = bary2bdigitdbl(xds, 2);
@@ -6044,11 +6064,11 @@ bigdivmod(VALUE x, VALUE y, volatile VALUE *divp, volatile VALUE *modp)
 
     bigdivrem(x, y, divp, &mod);
     if (BIGNUM_SIGN(x) != BIGNUM_SIGN(y) && !BIGZEROP(mod)) {
-	if (divp) *divp = bigadd(*divp, rb_int2big(1), 0);
-	if (modp) *modp = bigadd(mod, y, 1);
+        if (divp) *divp = bigadd(*divp, rb_int2big(1), 0);
+        if (modp) *modp = bigadd(mod, y, 1);
     }
     else if (modp) {
-	*modp = mod;
+        *modp = mod;
     }
 }
 
@@ -6059,25 +6079,25 @@ rb_big_divide(VALUE x, VALUE y, ID op)
     VALUE z;
 
     if (FIXNUM_P(y)) {
-	y = rb_int2big(FIX2LONG(y));
+        y = rb_int2big(FIX2LONG(y));
     }
     else if (RB_BIGNUM_TYPE_P(y)) {
     }
     else if (RB_FLOAT_TYPE_P(y)) {
-	if (op == '/') {
+        if (op == '/') {
             double dx = rb_big2dbl(x);
             return rb_flo_div_flo(DBL2NUM(dx), y);
-	}
-	else {
+        }
+        else {
             VALUE v;
-	    double dy = RFLOAT_VALUE(y);
-	    if (dy == 0.0) rb_num_zerodiv();
+            double dy = RFLOAT_VALUE(y);
+            if (dy == 0.0) rb_num_zerodiv();
             v = rb_big_divide(x, y, '/');
             return rb_dbl2big(RFLOAT_VALUE(v));
-	}
+        }
     }
     else {
-	return rb_num_coerce_bin(x, y, op);
+        return rb_num_coerce_bin(x, y, op);
     }
     bigdivmod(x, y, &z, 0);
 
@@ -6102,10 +6122,10 @@ rb_big_modulo(VALUE x, VALUE y)
     VALUE z;
 
     if (FIXNUM_P(y)) {
-	y = rb_int2big(FIX2LONG(y));
+        y = rb_int2big(FIX2LONG(y));
     }
     else if (!RB_BIGNUM_TYPE_P(y)) {
-	return rb_num_coerce_bin(x, y, '%');
+        return rb_num_coerce_bin(x, y, '%');
     }
     bigdivmod(x, y, 0, &z);
 
@@ -6118,10 +6138,10 @@ rb_big_remainder(VALUE x, VALUE y)
     VALUE z;
 
     if (FIXNUM_P(y)) {
-	y = rb_int2big(FIX2LONG(y));
+        y = rb_int2big(FIX2LONG(y));
     }
     else if (!RB_BIGNUM_TYPE_P(y)) {
-	return rb_num_coerce_bin(x, y, rb_intern("remainder"));
+        return rb_num_coerce_bin(x, y, rb_intern("remainder"));
     }
     bigdivrem(x, y, 0, &z);
 
@@ -6134,7 +6154,7 @@ rb_big_divmod(VALUE x, VALUE y)
     VALUE div, mod;
 
     if (FIXNUM_P(y)) {
-	y = rb_int2big(FIX2LONG(y));
+        y = rb_int2big(FIX2LONG(y));
     }
     else if (!RB_BIGNUM_TYPE_P(y)) {
         return rb_num_coerce_bin(x, y, idDivmod);
@@ -6148,9 +6168,9 @@ static VALUE
 big_shift(VALUE x, long n)
 {
     if (n < 0)
-	return big_lshift(x, 1+(unsigned long)(-(n+1)));
+        return big_lshift(x, 1+(unsigned long)(-(n+1)));
     else if (n > 0)
-	return big_rshift(x, (unsigned long)n);
+        return big_rshift(x, (unsigned long)n);
     return x;
 }
 
@@ -6174,9 +6194,9 @@ big_fdiv(VALUE x, VALUE y, long ey)
     l = ex - ey;
 #if SIZEOF_LONG > SIZEOF_INT
     {
-	/* Visual C++ can't be here */
-	if (l > INT_MAX) return HUGE_VAL;
-	if (l < INT_MIN) return 0.0;
+        /* Visual C++ can't be here */
+        if (l > INT_MAX) return HUGE_VAL;
+        if (l < INT_MIN) return 0.0;
     }
 #endif
     return ldexp(big2dbl(z), (int)l);
@@ -6210,19 +6230,19 @@ rb_big_fdiv_double(VALUE x, VALUE y)
 
     dx = big2dbl(x);
     if (FIXNUM_P(y)) {
-	dy = (double)FIX2LONG(y);
-	if (isinf(dx))
-	    return big_fdiv_int(x, rb_int2big(FIX2LONG(y)));
+        dy = (double)FIX2LONG(y);
+        if (isinf(dx))
+            return big_fdiv_int(x, rb_int2big(FIX2LONG(y)));
     }
     else if (RB_BIGNUM_TYPE_P(y)) {
-	return big_fdiv_int(x, y);
+        return big_fdiv_int(x, y);
     }
     else if (RB_FLOAT_TYPE_P(y)) {
-	dy = RFLOAT_VALUE(y);
-	if (isnan(dy))
-	    return dy;
-	if (isinf(dx))
-	    return big_fdiv_float(x, y);
+        dy = RFLOAT_VALUE(y);
+        if (isnan(dy))
+            return dy;
+        if (isinf(dx))
+            return big_fdiv_float(x, y);
     }
     else {
         return NUM2DBL(rb_num_coerce_bin(x, y, idFdiv));
@@ -6247,20 +6267,20 @@ rb_big_pow(VALUE x, VALUE y)
     if (y == INT2FIX(0)) return INT2FIX(1);
     if (y == INT2FIX(1)) return x;
     if (RB_FLOAT_TYPE_P(y)) {
-	d = RFLOAT_VALUE(y);
-	if ((BIGNUM_NEGATIVE_P(x) && !BIGZEROP(x))) {
+        d = RFLOAT_VALUE(y);
+        if ((BIGNUM_NEGATIVE_P(x) && !BIGZEROP(x))) {
             return rb_dbl_complex_new_polar_pi(pow(-rb_big2dbl(x), d), d);
-	}
+        }
     }
     else if (RB_BIGNUM_TYPE_P(y)) {
-	y = bignorm(y);
-	if (FIXNUM_P(y))
-	    goto again;
-	rb_warn("in a**b, b may be too big");
-	d = rb_big2dbl(y);
+        y = bignorm(y);
+        if (FIXNUM_P(y))
+            goto again;
+        rb_warn("in a**b, b may be too big");
+        d = rb_big2dbl(y);
     }
     else if (FIXNUM_P(y)) {
-	yy = FIX2LONG(y);
+        yy = FIX2LONG(y);
 
         if (yy < 0) {
             x = rb_big_pow(x, LONG2NUM(-yy));
@@ -6269,31 +6289,31 @@ rb_big_pow(VALUE x, VALUE y)
             else
                 return DBL2NUM(1.0 / NUM2DBL(x));
         }
-	else {
-	    VALUE z = 0;
-	    SIGNED_VALUE mask;
+        else {
+            VALUE z = 0;
+            SIGNED_VALUE mask;
             const size_t xbits = rb_absint_numwords(x, 1, NULL);
-	    const size_t BIGLEN_LIMIT = 32*1024*1024;
+            const size_t BIGLEN_LIMIT = 32*1024*1024;
 
-	    if (xbits == (size_t)-1 ||
+            if (xbits == (size_t)-1 ||
                 (xbits > BIGLEN_LIMIT) ||
                 (xbits * yy > BIGLEN_LIMIT)) {
-		rb_warn("in a**b, b may be too big");
-		d = (double)yy;
-	    }
-	    else {
-		for (mask = FIXNUM_MAX + 1; mask; mask >>= 1) {
-		    if (z) z = bigsq(z);
-		    if (yy & mask) {
-			z = z ? bigtrunc(bigmul0(z, x)) : x;
-		    }
-		}
-		return bignorm(z);
-	    }
-	}
+                rb_warn("in a**b, b may be too big");
+                d = (double)yy;
+            }
+            else {
+                for (mask = FIXNUM_MAX + 1; mask; mask >>= 1) {
+                    if (z) z = bigsq(z);
+                    if (yy & mask) {
+                        z = z ? bigtrunc(bigmul0(z, x)) : x;
+                    }
+                }
+                return bignorm(z);
+            }
+        }
     }
     else {
-	return rb_num_coerce_bin(x, y, idPow);
+        return rb_num_coerce_bin(x, y, idPow);
     }
     return DBL2NUM(pow(rb_big2dbl(x), d));
 }
@@ -6313,8 +6333,8 @@ bigand_int(VALUE x, long xn, BDIGIT hibitsx, long y)
     xds = BDIGITS(x);
 #if SIZEOF_BDIGIT >= SIZEOF_LONG
     if (!hibitsy) {
-	y &= xds[0];
-	return LONG2NUM(y);
+        y &= xds[0];
+        return LONG2NUM(y);
     }
 #endif
 
@@ -6343,10 +6363,10 @@ bigand_int(VALUE x, long xn, BDIGIT hibitsx, long y)
     }
 #endif
     for (;i < xn; i++) {
-	zds[i] = xds[i] & hibitsy;
+        zds[i] = xds[i] & hibitsy;
     }
     for (;i < zn; i++) {
-	zds[i] = hibitsx & hibitsy;
+        zds[i] = hibitsx & hibitsy;
     }
     twocomp2abs_bang(z, hibitsx && hibitsy);
     RB_GC_GUARD(x);
@@ -6366,12 +6386,12 @@ rb_big_and(VALUE x, VALUE y)
     long tmpn;
 
     if (!RB_INTEGER_TYPE_P(y)) {
-	return rb_num_coerce_bit(x, y, '&');
+        return rb_num_coerce_bit(x, y, '&');
     }
 
     hibitsx = abs2twocomp(&x, &xn);
     if (FIXNUM_P(y)) {
-	return bigand_int(x, xn, hibitsx, FIX2LONG(y));
+        return bigand_int(x, xn, hibitsx, FIX2LONG(y));
     }
     hibitsy = abs2twocomp(&y, &yn);
     if (xn > yn) {
@@ -6393,10 +6413,10 @@ rb_big_and(VALUE x, VALUE y)
     zds = BDIGITS(z);
 
     for (i=0; i<n1; i++) {
-	zds[i] = ds1[i] & ds2[i];
+        zds[i] = ds1[i] & ds2[i];
     }
     for (; i<n2; i++) {
-	zds[i] = hibits1 & ds2[i];
+        zds[i] = hibits1 & ds2[i];
     }
     twocomp2abs_bang(z, hibits1 && hibits2);
     RB_GC_GUARD(x);
@@ -6485,12 +6505,12 @@ rb_big_or(VALUE x, VALUE y)
     long tmpn;
 
     if (!RB_INTEGER_TYPE_P(y)) {
-	return rb_num_coerce_bit(x, y, '|');
+        return rb_num_coerce_bit(x, y, '|');
     }
 
     hibitsx = abs2twocomp(&x, &xn);
     if (FIXNUM_P(y)) {
-	return bigor_int(x, xn, hibitsx, FIX2LONG(y));
+        return bigor_int(x, xn, hibitsx, FIX2LONG(y));
     }
     hibitsy = abs2twocomp(&y, &yn);
     if (xn > yn) {
@@ -6512,10 +6532,10 @@ rb_big_or(VALUE x, VALUE y)
     zds = BDIGITS(z);
 
     for (i=0; i<n1; i++) {
-	zds[i] = ds1[i] | ds2[i];
+        zds[i] = ds1[i] | ds2[i];
     }
     for (; i<n2; i++) {
-	zds[i] = hibits1 | ds2[i];
+        zds[i] = hibits1 | ds2[i];
     }
     twocomp2abs_bang(z, hibits1 || hibits2);
     RB_GC_GUARD(x);
@@ -6579,12 +6599,12 @@ rb_big_xor(VALUE x, VALUE y)
     long tmpn;
 
     if (!RB_INTEGER_TYPE_P(y)) {
-	return rb_num_coerce_bit(x, y, '^');
+        return rb_num_coerce_bit(x, y, '^');
     }
 
     hibitsx = abs2twocomp(&x, &xn);
     if (FIXNUM_P(y)) {
-	return bigxor_int(x, xn, hibitsx, FIX2LONG(y));
+        return bigxor_int(x, xn, hibitsx, FIX2LONG(y));
     }
     hibitsy = abs2twocomp(&y, &yn);
     if (xn > yn) {
@@ -6603,10 +6623,10 @@ rb_big_xor(VALUE x, VALUE y)
     zds = BDIGITS(z);
 
     for (i=0; i<n1; i++) {
-	zds[i] = ds1[i] ^ ds2[i];
+        zds[i] = ds1[i] ^ ds2[i];
     }
     for (; i<n2; i++) {
-	zds[i] = hibitsx ^ ds2[i];
+        zds[i] = hibitsx ^ ds2[i];
     }
     twocomp2abs_bang(z, (hibits1 ^ hibits2) != 0);
     RB_GC_GUARD(x);
@@ -6622,25 +6642,25 @@ rb_big_lshift(VALUE x, VALUE y)
     int shift_numbits;
 
     for (;;) {
-	if (FIXNUM_P(y)) {
-	    long l = FIX2LONG(y);
+        if (FIXNUM_P(y)) {
+            long l = FIX2LONG(y);
             unsigned long shift;
-	    if (0 <= l) {
-		lshift_p = 1;
+            if (0 <= l) {
+                lshift_p = 1;
                 shift = l;
             }
             else {
-		lshift_p = 0;
-		shift = 1+(unsigned long)(-(l+1));
-	    }
+                lshift_p = 0;
+                shift = 1+(unsigned long)(-(l+1));
+            }
             shift_numbits = (int)(shift & (BITSPERDIG-1));
             shift_numdigits = shift >> bit_length(BITSPERDIG-1);
             return bignorm(big_shift3(x, lshift_p, shift_numdigits, shift_numbits));
-	}
-	else if (RB_BIGNUM_TYPE_P(y)) {
+        }
+        else if (RB_BIGNUM_TYPE_P(y)) {
             return bignorm(big_shift2(x, 1, y));
-	}
-	y = rb_to_int(y);
+        }
+        y = rb_to_int(y);
     }
 }
 
@@ -6652,8 +6672,8 @@ rb_big_rshift(VALUE x, VALUE y)
     int shift_numbits;
 
     for (;;) {
-	if (FIXNUM_P(y)) {
-	    long l = FIX2LONG(y);
+        if (FIXNUM_P(y)) {
+            long l = FIX2LONG(y);
             unsigned long shift;
             if (0 <= l) {
                 lshift_p = 0;
@@ -6661,16 +6681,16 @@ rb_big_rshift(VALUE x, VALUE y)
             }
             else {
                 lshift_p = 1;
-		shift = 1+(unsigned long)(-(l+1));
-	    }
+                shift = 1+(unsigned long)(-(l+1));
+            }
             shift_numbits = (int)(shift & (BITSPERDIG-1));
             shift_numdigits = shift >> bit_length(BITSPERDIG-1);
             return bignorm(big_shift3(x, lshift_p, shift_numdigits, shift_numbits));
-	}
-	else if (RB_BIGNUM_TYPE_P(y)) {
+        }
+        else if (RB_BIGNUM_TYPE_P(y)) {
             return bignorm(big_shift2(x, 0, y));
-	}
-	y = rb_to_int(y);
+        }
+        y = rb_to_int(y);
     }
 }
 
@@ -6684,22 +6704,22 @@ rb_big_aref(VALUE x, VALUE y)
     BDIGIT bit;
 
     if (RB_BIGNUM_TYPE_P(y)) {
-	if (BIGNUM_NEGATIVE_P(y))
-	    return INT2FIX(0);
-	bigtrunc(y);
-	if (BIGSIZE(y) > sizeof(size_t)) {
-	    return BIGNUM_SIGN(x) ? INT2FIX(0) : INT2FIX(1);
-	}
+        if (BIGNUM_NEGATIVE_P(y))
+            return INT2FIX(0);
+        bigtrunc(y);
+        if (BIGSIZE(y) > sizeof(size_t)) {
+            return BIGNUM_SIGN(x) ? INT2FIX(0) : INT2FIX(1);
+        }
 #if SIZEOF_SIZE_T <= SIZEOF_LONG
-	shift = big2ulong(y, "long");
+        shift = big2ulong(y, "long");
 #else
-	shift = big2ull(y, "long long");
+        shift = big2ull(y, "long long");
 #endif
     }
     else {
-	l = NUM2LONG(y);
-	if (l < 0) return INT2FIX(0);
-	shift = (size_t)l;
+        l = NUM2LONG(y);
+        if (l < 0) return INT2FIX(0);
+        shift = (size_t)l;
     }
     s1 = shift/BITSPERDIG;
     s2 = shift%BITSPERDIG;
@@ -6760,8 +6780,8 @@ VALUE
 rb_big_abs(VALUE x)
 {
     if (BIGNUM_NEGATIVE_P(x)) {
-	x = rb_big_clone(x);
-	BIGNUM_SET_POSITIVE_SIGN(x);
+        x = rb_big_clone(x);
+        BIGNUM_SET_POSITIVE_SIGN(x);
     }
     return x;
 }
@@ -6835,7 +6855,7 @@ VALUE
 rb_big_even_p(VALUE num)
 {
     if (BIGNUM_LEN(num) != 0 && BDIGITS(num)[0] & 1) {
-	return Qfalse;
+        return Qfalse;
     }
     return Qtrue;
 }
@@ -6866,21 +6886,21 @@ estimate_initial_sqrt(VALUE *xp, const size_t xn, const BDIGIT *nds, size_t len)
     double f;
 
     if (rshift > 0) {
-	lowbits = (BDIGIT)d & ~(~(BDIGIT)1U << rshift);
-	d >>= rshift;
+        lowbits = (BDIGIT)d & ~(~(BDIGIT)1U << rshift);
+        d >>= rshift;
     }
     else if (rshift < 0) {
-	d <<= -rshift;
-	d |= nds[len-dbl_per_bdig-1] >> (BITSPERDIG+rshift);
+        d <<= -rshift;
+        d |= nds[len-dbl_per_bdig-1] >> (BITSPERDIG+rshift);
     }
     f = sqrt(BDIGIT_DBL_TO_DOUBLE(d));
     d = (BDIGIT_DBL)ceil(f);
     if (BDIGIT_DBL_TO_DOUBLE(d) == f) {
-	if (lowbits || (lowbits = !bary_zero_p(nds, len-dbl_per_bdig)))
-	    ++d;
+        if (lowbits || (lowbits = !bary_zero_p(nds, len-dbl_per_bdig)))
+            ++d;
     }
     else {
-	lowbits = 1;
+        lowbits = 1;
     }
     rshift /= 2;
     rshift += (2-(len&1))*BITSPERDIG/2;
@@ -6912,35 +6932,35 @@ rb_big_isqrt(VALUE n)
     BDIGIT *xds;
 
     if (len <= 2) {
-	BDIGIT sq = rb_bdigit_dbl_isqrt(bary2bdigitdbl(nds, len));
+        BDIGIT sq = rb_bdigit_dbl_isqrt(bary2bdigitdbl(nds, len));
 #if SIZEOF_BDIGIT > SIZEOF_LONG
-	return ULL2NUM(sq);
+        return ULL2NUM(sq);
 #else
-	return ULONG2NUM(sq);
+        return ULONG2NUM(sq);
 #endif
     }
     else if ((xds = estimate_initial_sqrt(&x, xn, nds, len)) != 0) {
-	size_t tn = xn + BIGDIVREM_EXTRA_WORDS;
-	VALUE t = bignew_1(0, tn, 1);
-	BDIGIT *tds = BDIGITS(t);
-	tn = BIGNUM_LEN(t);
-
-	/* t = n/x */
-	while (bary_divmod_branch(tds, tn, NULL, 0, nds, len, xds, xn),
-	       bary_cmp(tds, tn, xds, xn) < 0) {
-	    int carry;
-	    BARY_TRUNC(tds, tn);
-	    /* x = (x+t)/2 */
-	    carry = bary_add(xds, xn, xds, xn, tds, tn);
-	    bary_small_rshift(xds, xds, xn, 1, carry);
-	    tn = BIGNUM_LEN(t);
-	}
+        size_t tn = xn + BIGDIVREM_EXTRA_WORDS;
+        VALUE t = bignew_1(0, tn, 1);
+        BDIGIT *tds = BDIGITS(t);
+        tn = BIGNUM_LEN(t);
+
+        /* t = n/x */
+        while (bary_divmod_branch(tds, tn, NULL, 0, nds, len, xds, xn),
+               bary_cmp(tds, tn, xds, xn) < 0) {
+            int carry;
+            BARY_TRUNC(tds, tn);
+            /* x = (x+t)/2 */
+            carry = bary_add(xds, xn, xds, xn, tds, tn);
+            bary_small_rshift(xds, xds, xn, 1, carry);
+            tn = BIGNUM_LEN(t);
+        }
     }
     RBASIC_SET_CLASS_RAW(x, rb_cInteger);
     return x;
 }
 
-#ifdef USE_GMP
+#if USE_GMP
 static void
 bary_powm_gmp(BDIGIT *zds, size_t zn, const BDIGIT *xds, size_t xn, const BDIGIT *yds, size_t yn, const BDIGIT *mds, size_t mn)
 {
@@ -6966,7 +6986,7 @@ bary_powm_gmp(BDIGIT *zds, size_t zn, const BDIGIT *xds, size_t xn, const BDIGIT
 static VALUE
 int_pow_tmp3(VALUE x, VALUE y, VALUE m, int nega_flg)
 {
-#ifdef USE_GMP
+#if USE_GMP
     VALUE z;
     size_t xn, yn, mn, zn;
 
@@ -7142,7 +7162,7 @@ rb_int_powm(int const argc, VALUE * const argv, VALUE const num)
         }
         else {
             if (rb_bigzero_p(m)) rb_num_zerodiv();
-	    if (bignorm(m) == INT2FIX(1)) return INT2FIX(0);
+            if (bignorm(m) == INT2FIX(1)) return INT2FIX(0);
             return int_pow_tmp3(rb_int_modulo(a, m), b, m, nega_flg);
         }
     }
@@ -7172,7 +7192,7 @@ Init_Bignum(void)
 {
     rb_define_method(rb_cInteger, "coerce", rb_int_coerce, 1);
 
-#ifdef USE_GMP
+#if USE_GMP
     /* The version of loaded GMP. */
     rb_define_const(rb_cInteger, "GMP_VERSION", rb_sprintf("GMP %s", gmp_version));
 #endif
diff --git a/bin/gem b/bin/gem
index a4ec754abb..1c16ea7ddd 100755
--- a/bin/gem
+++ b/bin/gem
@@ -5,21 +5,6 @@
 # See LICENSE.txt for permissions.
 #++
 
-require 'rubygems'
-require 'rubygems/gem_runner'
-require 'rubygems/exceptions'
-
-required_version = Gem::Requirement.new ">= 1.8.7"
-
-unless required_version.satisfied_by? Gem.ruby_version then
-  abort "Expected Ruby Version #{required_version}, is #{Gem.ruby_version}"
-end
-
-args = ARGV.clone
-
-begin
-  Gem::GemRunner.new.run args
-rescue Gem::SystemExitException => e
-  exit e.exit_code
-end
+require "rubygems/gem_runner"
 
+Gem::GemRunner.new.run ARGV.clone
diff --git a/bootstraptest/runner.rb b/bootstraptest/runner.rb
index 3d42390254..f9b3e919b8 100755
--- a/bootstraptest/runner.rb
+++ b/bootstraptest/runner.rb
@@ -61,7 +61,7 @@ if !Dir.respond_to?(:mktmpdir)
 end
 
 # Configuration
-BT = Struct.new(:ruby,
+bt = Struct.new(:ruby,
                 :verbose,
                 :color,
                 :tty,
@@ -73,9 +73,78 @@ BT = Struct.new(:ruby,
                 :failed,
                 :reset,
                 :columns,
+                :window_width,
                 :width,
+                :indent,
                 :platform,
-                ).new
+                )
+BT = Class.new(bt) do
+  def indent=(n)
+    super
+    if (self.columns ||= 0) < n
+      $stderr.print(' ' * (n - self.columns))
+    end
+    self.columns = indent
+  end
+
+  def putc(c)
+    unless self.quiet
+      if self.window_width == nil
+        unless w = ENV["COLUMNS"] and (w = w.to_i) > 0
+          w = 80
+        end
+        w -= 1
+        self.window_width = w
+      end
+      if self.window_width and self.columns >= self.window_width
+        $stderr.print "\n", " " * (self.indent ||= 0)
+        self.columns = indent
+      end
+      $stderr.print c
+      $stderr.flush
+      self.columns += 1
+    end
+  end
+
+  def wn=(wn)
+    unless wn == 1
+      if /(?:\A|\s)--jobserver-(?:auth|fds)=(?:(\d+),(\d+)|fifo:((?:\\.|\S)+))/ =~ ENV.delete("MAKEFLAGS")
+        begin
+          if fifo = $3
+            fifo.gsub!(/\\(?=.)/, '')
+            r = File.open(fifo, IO::RDONLY|IO::NONBLOCK|IO::BINARY)
+            w = File.open(fifo, IO::WRONLY|IO::NONBLOCK|IO::BINARY)
+          else
+            r = IO.for_fd($1.to_i(10), "rb", autoclose: false)
+            w = IO.for_fd($2.to_i(10), "wb", autoclose: false)
+          end
+        rescue => e
+          r.close if r
+        else
+          r.close_on_exec = true
+          w.close_on_exec = true
+          tokens = r.read_nonblock(wn > 0 ? wn : 1024, exception: false)
+          r.close
+          if String === tokens
+            tokens.freeze
+            auth = w
+            w = nil
+            at_exit {auth << tokens; auth.close}
+            wn = tokens.size + 1
+          else
+            w.close
+            wn = 1
+          end
+        end
+      end
+      if wn <= 0
+        require 'etc'
+        wn = [Etc.nprocessors / 2, 1].max
+      end
+    end
+    super wn
+  end
+end.new
 
 BT_STATE = Struct.new(:count, :error).new
 
@@ -87,7 +156,7 @@ def main
   BT.color = nil
   BT.tty = nil
   BT.quiet = false
-  BT.wn = 1
+  # BT.wn = 1
   dir = nil
   quiet = false
   tests = nil
@@ -122,12 +191,7 @@ def main
       BT.quiet = true
       true
     when /\A-j(\d+)?/
-      wn = $1.to_i
-      if wn <= 0
-        require 'etc'
-        wn = [Etc.nprocessors / 2, 1].max
-      end
-      BT.wn = wn
+      BT.wn = $1.to_i
       true
     when /\A(-v|--v(erbose))\z/
       BT.verbose = true
@@ -154,8 +218,7 @@ End
     end
   }
   if tests and not ARGV.empty?
-    $stderr.puts "--tests and arguments are exclusive"
-    exit false
+    abort "--sets and arguments are exclusive"
   end
   tests ||= ARGV
   tests = Dir.glob("#{File.dirname($0)}/test_*.rb").sort if tests.empty?
@@ -164,6 +227,7 @@ End
   BT.progress = %w[- \\ | /]
   BT.progress_bs = "\b" * BT.progress[0].size
   BT.tty = $stderr.tty? if BT.tty.nil?
+  BT.wn ||= /-j(\d+)?/ =~ (ENV["MAKEFLAGS"] || ENV["MFLAGS"]) ? $1.to_i : 1
 
   case BT.color
   when nil
@@ -241,7 +305,7 @@ def concurrent_exec_test
     end
   end
 
-  $stderr.print ' ' unless BT.quiet
+  BT.indent = 1
   aq.close
   i = 1
   term_wn = 0
@@ -253,7 +317,7 @@ def concurrent_exec_test
         when BT.tty
           $stderr.print "#{BT.progress_bs}#{BT.progress[(i+=1) % BT.progress.size]}"
         else
-          $stderr.print '.'
+          BT.putc '.'
         end
       else
         term_wn += 1
@@ -275,7 +339,7 @@ def exec_test(pathes)
 
   # execute tests
   if BT.wn > 1
-    concurrent_exec_test if BT.wn > 1
+    concurrent_exec_test
   else
     prev_basename = nil
     Assertion.all.each do |basename, assertions|
@@ -428,7 +492,7 @@ class Assertion < Struct.new(:src, :path, :lineno, :proc)
       elsif BT.verbose
         $stderr.printf(". %.3f\n", t)
       else
-        $stderr.print '.'
+        BT.putc '.'
       end
     else
       $stderr.print "#{BT.failed}F"
diff --git a/bootstraptest/test_attr.rb b/bootstraptest/test_attr.rb
index 721a847145..3cb9d3eb39 100644
--- a/bootstraptest/test_attr.rb
+++ b/bootstraptest/test_attr.rb
@@ -34,3 +34,19 @@ assert_equal %{ok}, %{
     print "ok"
   end
 }, '[ruby-core:15120]'
+
+assert_equal %{ok}, %{
+  class Big
+    attr_reader :foo
+    def initialize
+      @foo = "ok"
+    end
+  end
+
+  obj = Big.new
+  100.times do |i|
+    obj.instance_variable_set(:"@ivar_\#{i}", i)
+  end
+
+  Big.new.foo
+}
diff --git a/bootstraptest/test_io.rb b/bootstraptest/test_io.rb
index 73deca8383..666e5a011b 100644
--- a/bootstraptest/test_io.rb
+++ b/bootstraptest/test_io.rb
@@ -1,3 +1,4 @@
+/freebsd/ =~ RUBY_PLATFORM or
 assert_finish 5, %q{
   r, w = IO.pipe
   t1 = Thread.new { r.sysread(1) }
@@ -30,6 +31,7 @@ assert_finish 10, %q{
   end
 }, '[ruby-dev:32566]'
 
+/freebsd/ =~ RUBY_PLATFORM or
 assert_finish 5, %q{
   r, w = IO.pipe
   Thread.new {
@@ -83,6 +85,7 @@ assert_normal_exit %q{
   ARGF.set_encoding "foo"
 }
 
+/freebsd/ =~ RUBY_PLATFORM or
 10.times do
   assert_normal_exit %q{
     at_exit { p :foo }
diff --git a/bootstraptest/test_ractor.rb b/bootstraptest/test_ractor.rb
index b29db7ab0e..67e66b03ee 100644
--- a/bootstraptest/test_ractor.rb
+++ b/bootstraptest/test_ractor.rb
@@ -283,8 +283,9 @@ assert_equal 30.times.map { 'ok' }.to_s, %q{
   30.times.map{|i|
     test i
   }
-} unless ENV['RUN_OPTS'] =~ /--jit-min-calls=5/ || # This always fails with --jit-wait --jit-min-calls=5
-  (ENV.key?('TRAVIS') && ENV['TRAVIS_CPU_ARCH'] == 'arm64') # https://bugs.ruby-lang.org/issues/17878
+} unless ENV['RUN_OPTS'] =~ /--mjit-call-threshold=5/ || # This always fails with --mjit-wait --mjit-call-threshold=5
+  (ENV.key?('TRAVIS') && ENV['TRAVIS_CPU_ARCH'] == 'arm64') || # https://bugs.ruby-lang.org/issues/17878
+  true # too flaky everywhere http://ci.rvm.jp/results/trunk@ruby-sp1/4321096
 
 # Exception for empty select
 assert_match /specify at least one ractor/, %q{
@@ -501,7 +502,7 @@ assert_equal '[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]', %q{
     rs.delete r
     n
   }.sort
-}
+} unless /mswin/ =~ RUBY_PLATFORM # randomly hangs on mswin https://github.com/ruby/ruby/actions/runs/3753871445/jobs/6377551069#step:20:131
 
 # Ractor.select also support multiple take, receive and yield
 assert_equal '[true, true, true]', %q{
@@ -1472,7 +1473,7 @@ assert_equal "#{N}#{N}", %Q{
 }
 
 # enc_table
-assert_equal "#{N/10}", %Q{
+assert_equal "100", %Q{
   Ractor.new do
     loop do
       Encoding.find("test-enc-#{rand(5_000)}").inspect
@@ -1481,7 +1482,7 @@ assert_equal "#{N/10}", %Q{
   end
 
   src = Encoding.find("UTF-8")
-  #{N/10}.times{|i|
+  100.times{|i|
     src.replicate("test-enc-\#{i}")
   }
 }
@@ -1579,4 +1580,49 @@ assert_equal "ok", %q{
   end
 }
 
+assert_equal "ok", %q{
+  module M
+    def foo
+      @foo
+    end
+  end
+
+  class A
+    include M
+
+    def initialize
+      100.times { |i| instance_variable_set(:"@var_#{i}", "bad: #{i}") }
+      @foo = 2
+    end
+  end
+
+  class B
+    include M
+
+    def initialize
+      @foo = 1
+    end
+  end
+
+  Ractor.new do
+    b = B.new
+    100_000.times do
+      raise unless b.foo == 1
+    end
+  end
+
+  a = A.new
+  100_000.times do
+    raise unless a.foo == 2
+  end
+
+  "ok"
+}
+
+assert_match /\Atest_ractor\.rb:1:\s+warning:\s+Ractor is experimental/, %q{
+  Warning[:experimental] = $VERBOSE = true
+  STDERR.reopen(STDOUT)
+  eval("Ractor.new{}.take", nil, "test_ractor.rb", 1)
+}
+
 end # if !ENV['GITHUB_WORKFLOW']
diff --git a/bootstraptest/test_yjit.rb b/bootstraptest/test_yjit.rb
index a84a9e035a..5c655b8f25 100644
--- a/bootstraptest/test_yjit.rb
+++ b/bootstraptest/test_yjit.rb
@@ -1,3 +1,53 @@
+# Regression test for yielding with autosplat to block with
+# optional parameters. https://github.com/Shopify/yjit/issues/313
+assert_equal '[:a, :b, :a, :b]', %q{
+  def yielder(arg) = yield(arg) + yield(arg)
+
+  yielder([:a, :b]) do |c = :c, d = :d|
+    [c, d]
+  end
+}
+
+# Regression test for GC mishap while doing shape transition
+assert_equal '[:ok]', %q{
+  # [Bug #19601]
+  class RegressionTest
+    def initialize
+      @a = @b = @fourth_ivar_does_shape_transition = nil
+    end
+
+    def extender
+      @first_extended_ivar = [:ok]
+    end
+  end
+
+  GC.stress = true
+
+  # Used to crash due to GC run in rb_ensure_iv_list_size()
+  # not marking the newly allocated [:ok].
+  RegressionTest.new.extender.itself
+}
+
+assert_equal 'true', %q{
+  # regression test for tracking type of locals for too long
+  def local_setting_cmp(five)
+    victim = 5
+    five.define_singleton_method(:respond_to?) do |_, _|
+      victim = nil
+    end
+
+    # +1 makes YJIT track that victim is a number and
+    # defined? calls respond_to? from above indirectly
+    unless (victim + 1) && defined?(five.something)
+      # Would return wrong result if we still think `five` is a number
+      victim.nil?
+    end
+  end
+
+  local_setting_cmp(Object.new)
+  local_setting_cmp(Object.new)
+}
+
 assert_equal '18374962167983112447', %q{
   # regression test for incorrectly discarding 32 bits of a pointer when it
   # comes to default values.
@@ -14,7 +64,7 @@ assert_equal '18374962167983112447', %q{
 }
 
 assert_normal_exit %q{
-  # regression test for a leak caught by an asert on --yjit-call-threshold=2
+  # regression test for a leak caught by an assert on --yjit-call-threshold=2
   Foo = 1
 
   eval("def foo = [#{(['Foo,']*256).join}]")
@@ -25,6 +75,29 @@ assert_normal_exit %q{
   Object.send(:remove_const, :Foo)
 }
 
+assert_normal_exit %q{
+  # Test to ensure send on overriden c functions
+  # doesn't corrupt the stack
+  class Bar
+    def bar(x)
+      x
+    end
+  end
+
+  class Foo
+    def bar
+      Bar.new
+    end
+  end
+
+  foo = Foo.new
+  # before this change, this line would error
+  # because "s" would still be on the stack
+  # String.to_s is the overridden method here
+  p foo.bar.bar("s".__send__(:to_s))
+}
+
+
 assert_equal '[nil, nil, nil, nil, nil, nil]', %q{
   [NilClass, TrueClass, FalseClass, Integer, Float, Symbol].each do |klass|
     klass.class_eval("def foo = @foo")
@@ -178,6 +251,8 @@ assert_equal 'string', %q{
 
 # Check that exceptions work when getting global variable
 assert_equal 'rescued', %q{
+  Warning[:deprecated] = true
+
   module Warning
     def warn(message)
       raise
@@ -786,7 +861,7 @@ assert_equal "good", %q{
   foo
 
   begin
-    GC.verify_compaction_references(double_heap: true, toward: :empty)
+    GC.verify_compaction_references(expand_heap: true, toward: :empty)
   rescue NotImplementedError
     # in case compaction isn't supported
   end
@@ -1098,6 +1173,38 @@ assert_equal '42', %q{
   run
 }
 
+# splatting an empty array on a specialized method
+assert_equal 'ok', %q{
+  def run
+    "ok".to_s(*[])
+  end
+
+  run
+  run
+}
+
+# splatting an single element array on a specialized method
+assert_equal '[1]', %q{
+  def run
+    [].<<(*[1])
+  end
+
+  run
+  run
+}
+
+# specialized method with wrong args
+assert_equal 'ok', %q{
+  def run(x)
+    "bad".to_s(123) if x
+  rescue
+    :ok
+  end
+
+  run(false)
+  run(true)
+}
+
 # getinstancevariable on Symbol
 assert_equal '[nil, nil]', %q{
   # @foo to exercise the getinstancevariable instruction
@@ -1204,6 +1311,19 @@ assert_equal '[1, 2, 42]', %q{
   [foo {1}, foo {2}, foo {42}]
 }
 
+# test calling without block param
+assert_equal '[1, false, 2, false]', %q{
+  def bar
+    block_given? && yield
+  end
+
+  def foo(&block)
+    bar(&block)
+  end
+
+  [foo { 1 }, foo, foo { 2 }, foo]
+}
+
 # test calling block param failing
 assert_equal '42', %q{
   def foo(&block)
@@ -1337,6 +1457,46 @@ assert_equal 'foo123', %q{
   make_str("foo", 123)
 }
 
+# test that invalidation of String#to_s doesn't crash
+assert_equal 'meh', %q{
+  def inval_method
+    "".to_s
+  end
+
+  inval_method
+
+  class String
+    def to_s
+      "meh"
+    end
+  end
+
+  inval_method
+}
+
+# test that overriding to_s on a String subclass works consistently
+assert_equal 'meh', %q{
+  class MyString < String
+    def to_s
+      "meh"
+    end
+  end
+
+  def test_to_s(obj)
+    obj.to_s
+  end
+
+  OBJ = MyString.new
+
+  # Should return '' both times
+  test_to_s("")
+  test_to_s("")
+
+  # Can return '' if YJIT optimises String#to_s too aggressively
+  test_to_s(OBJ)
+  test_to_s(OBJ)
+}
+
 # test string interpolation with overridden to_s
 assert_equal 'foo', %q{
   class String
@@ -1353,6 +1513,149 @@ assert_equal 'foo', %q{
   make_str("foo")
 }
 
+# Test that String unary plus returns the same object ID for an unfrozen string.
+assert_equal 'true', %q{
+  def jittable_method
+    str = "bar"
+
+    old_obj_id = str.object_id
+    uplus_str = +str
+
+    uplus_str.object_id == old_obj_id
+  end
+  jittable_method
+}
+
+# Test that String unary plus returns a different unfrozen string when given a frozen string
+assert_equal 'false', %q{
+  # Logic needs to be inside an ISEQ, such as a method, for YJIT to compile it
+  def jittable_method
+    frozen_str = "foo".freeze
+
+    old_obj_id = frozen_str.object_id
+    uplus_str = +frozen_str
+
+    uplus_str.object_id == old_obj_id || uplus_str.frozen?
+  end
+
+  jittable_method
+}
+
+# String-subclass objects should behave as expected inside string-interpolation via concatstrings
+assert_equal 'monkeys / monkeys, yo!', %q{
+  class MyString < String
+    # This is a terrible idea in production code, but we'd like YJIT to match CRuby
+    def to_s
+      super + ", yo!"
+    end
+  end
+
+  def jittable_method
+    m = MyString.new('monkeys')
+    "#{m} / #{m.to_s}"
+  end
+
+  jittable_method
+}
+
+# String-subclass objects should behave as expected for string equality
+assert_equal 'false', %q{
+  class MyString < String
+    # This is a terrible idea in production code, but we'd like YJIT to match CRuby
+    def ==(b)
+      "#{self}_" == b
+    end
+  end
+
+  def jittable_method
+    ma = MyString.new("a")
+
+    # Check equality with string-subclass receiver
+    ma == "a" || ma != "a_" ||
+      # Check equality with string receiver
+      "a_" == ma || "a" != ma ||
+      # Check equality between string subclasses
+      ma != MyString.new("a_") ||
+      # Make sure "string always equals itself" check isn't used with overridden equality
+      ma == ma
+  end
+  jittable_method
+}
+
+# Test to_s duplicates a string subclass object but not a string
+assert_equal 'false', %q{
+  class MyString < String; end
+
+  def jittable_method
+    a = "a"
+    ma = MyString.new("a")
+
+    a.object_id != a.to_s.object_id ||
+      ma.object_id == ma.to_s.object_id
+  end
+  jittable_method
+}
+
+# Test freeze on string subclass
+assert_equal 'true', %q{
+  class MyString < String; end
+
+  def jittable_method
+    fma = MyString.new("a").freeze
+
+    # Freezing a string subclass should not duplicate it
+    fma.object_id == fma.freeze.object_id
+  end
+  jittable_method
+}
+
+# Test unary minus on string subclass
+assert_equal 'true', %q{
+  class MyString < String; end
+
+  def jittable_method
+    ma = MyString.new("a")
+    fma = MyString.new("a").freeze
+
+    # Unary minus on frozen string subclass should not duplicate it
+    fma.object_id == (-fma).object_id &&
+      # Unary minus on unfrozen string subclass should duplicate it
+      ma.object_id != (-ma).object_id
+  end
+  jittable_method
+}
+
+# Test unary plus on string subclass
+assert_equal 'true', %q{
+  class MyString < String; end
+
+  def jittable_method
+    fma = MyString.new("a").freeze
+
+    # Unary plus on frozen string subclass should not duplicate it
+    fma.object_id != (+fma).object_id
+  end
+  jittable_method
+}
+
+# Test << operator on string subclass
+assert_equal 'abab', %q{
+  class MyString < String; end
+
+  def jittable_method
+    a = -"a"
+    mb = MyString.new("b")
+
+    buf = String.new
+    mbuf = MyString.new
+
+    buf << a << mb
+    mbuf << a << mb
+
+    buf + mbuf
+  end
+  jittable_method
+}
 
 # test invokebuiltin as used in struct assignment
 assert_equal '123', %q{
@@ -1934,7 +2237,7 @@ assert_equal '[[:c_return, :String, :string_alias, "events_to_str"]]', %q{
   events.compiled(events)
 
   events
-}
+} unless defined?(RubyVM::MJIT) && RubyVM::MJIT.enabled? # MJIT calls extra Ruby methods
 
 # test enabling a TracePoint that targets a particular line in a C method call
 assert_equal '[true]', %q{
@@ -2016,7 +2319,7 @@ assert_equal '[[:c_call, :itself]]', %q{
   tp.enable { shouldnt_compile }
 
   events
-}
+} unless defined?(RubyVM::MJIT) && RubyVM::MJIT.enabled? # MJIT calls extra Ruby methods
 
 # test enabling c_return tracing before compiling
 assert_equal '[[:c_return, :itself, main]]', %q{
@@ -2031,6 +2334,26 @@ assert_equal '[[:c_return, :itself, main]]', %q{
   tp.enable { shouldnt_compile }
 
   events
+} unless defined?(RubyVM::MJIT) && RubyVM::MJIT.enabled? # MJIT calls extra Ruby methods
+
+# test c_call invalidation
+assert_equal '[[:c_call, :itself]]', %q{
+  # enable the event once to make sure invalidation
+  # happens the second time we enable it
+  TracePoint.new(:c_call) {}.enable{}
+
+  def compiled
+    itself
+  end
+
+  # assume first call compiles
+  compiled
+
+  events = []
+  tp = TracePoint.new(:c_call) { |tp| events << [tp.event, tp.method_id] }
+  tp.enable { compiled }
+
+  events
 }
 
 # test enabling tracing for a suspended fiber
@@ -2057,7 +2380,6 @@ assert_equal '[:itself]', %q{
     itself
   end
 
-
   tracing_ractor = Ractor.new do
     # 1: start tracing
     events = []
@@ -2686,11 +3008,20 @@ assert_equal 'new', %q{
     foo
   end
 
+  def bar
+    :bar
+  end
+
+
   test
   test
 
   RubyVM::YJIT.simulate_oom! if defined?(RubyVM::YJIT)
 
+  # Old simulat_omm! leaves one byte of space and this fills it up
+  bar
+  bar
+
   def foo
     :new
   end
@@ -2806,3 +3137,394 @@ assert_equal '', %q{
   foo
   foo
 }
+
+# Make sure we're correctly reading RStruct's as.ary union for embedded RStructs
+assert_equal '3,12', %q{
+  pt_struct = Struct.new(:x, :y)
+  p = pt_struct.new(3, 12)
+  def pt_inspect(pt)
+    "#{pt.x},#{pt.y}"
+  end
+
+  # Make sure pt_inspect is JITted
+  10.times { pt_inspect(p) }
+
+  # Make sure it's returning '3,12' instead of e.g. '3,false'
+  pt_inspect(p)
+}
+
+# Regression test for deadlock between branch_stub_hit and ractor_receive_if
+assert_equal '10', %q{
+  r = Ractor.new Ractor.current do |main|
+    main << 1
+    main << 2
+    main << 3
+    main << 4
+    main << 5
+    main << 6
+    main << 7
+    main << 8
+    main << 9
+    main << 10
+  end
+
+  a = []
+  a << Ractor.receive_if{|msg| msg == 10}
+  a << Ractor.receive_if{|msg| msg == 9}
+  a << Ractor.receive_if{|msg| msg == 8}
+  a << Ractor.receive_if{|msg| msg == 7}
+  a << Ractor.receive_if{|msg| msg == 6}
+  a << Ractor.receive_if{|msg| msg == 5}
+  a << Ractor.receive_if{|msg| msg == 4}
+  a << Ractor.receive_if{|msg| msg == 3}
+  a << Ractor.receive_if{|msg| msg == 2}
+  a << Ractor.receive_if{|msg| msg == 1}
+
+  a.length
+}
+
+# checktype
+assert_equal 'false', %q{
+    def function()
+        [1, 2] in [Integer, String]
+    end
+    function()
+}
+
+# opt_send_without_block (VM_METHOD_TYPE_ATTRSET)
+assert_equal 'foo', %q{
+    class Foo
+      attr_writer :foo
+
+      def foo()
+        self.foo = "foo"
+      end
+    end
+    foo = Foo.new
+    foo.foo
+}
+
+# anytostring, intern
+assert_equal 'true', %q{
+    def foo()
+      :"#{true}"
+    end
+    foo()
+}
+
+# toregexp, objtostring
+assert_equal '/true/', %q{
+    def foo()
+      /#{true}/
+    end
+    foo().inspect
+}
+
+# concatstrings, objtostring
+assert_equal '9001', %q{
+    def foo()
+      "#{9001}"
+    end
+    foo()
+}
+
+# opt_send_without_block (VM_METHOD_TYPE_CFUNC)
+assert_equal 'nil', %q{
+    def foo
+      nil.inspect # argc: 0
+    end
+    foo
+}
+assert_equal '4', %q{
+    def foo
+      2.pow(2) # argc: 1
+    end
+    foo
+}
+assert_equal 'aba', %q{
+    def foo
+      "abc".tr("c", "a") # argc: 2
+    end
+    foo
+}
+assert_equal 'true', %q{
+    def foo
+      respond_to?(:inspect) # argc: -1
+    end
+    foo
+}
+assert_equal '["a", "b"]', %q{
+    def foo
+      "a\nb".lines(chomp: true) # kwargs
+    end
+    foo
+}
+
+# invokebuiltin
+assert_equal '123', %q{
+  def foo(obj)
+    obj.foo = 123
+  end
+
+  struct = Struct.new(:foo)
+  obj = struct.new
+  foo(obj)
+}
+
+# invokebuiltin_delegate
+assert_equal '.', %q{
+  def foo(path)
+    Dir.open(path).path
+  end
+  foo(".")
+}
+
+# opt_invokebuiltin_delegate_leave
+assert_equal '[0]', %q{"\x00".unpack("c")}
+
+# opt_send_without_block (VM_METHOD_TYPE_ISEQ)
+assert_equal '1', %q{
+  def foo = 1
+  def bar = foo
+  bar
+}
+assert_equal '[1, 2, 3]', %q{
+  def foo(a, b) = [1, a, b]
+  def bar = foo(2, 3)
+  bar
+}
+assert_equal '[1, 2, 3, 4, 5, 6]', %q{
+  def foo(a, b, c:, d:, e: 0, f: 6) = [a, b, c, d, e, f]
+  def bar = foo(1, 2, c: 3, d: 4, e: 5)
+  bar
+}
+assert_equal '[1, 2, 3, 4]', %q{
+  def foo(a, b = 2) = [a, b]
+  def bar = foo(1) + foo(3, 4)
+  bar
+}
+
+assert_equal '1', %q{
+  def foo(a) = a
+  def bar = foo(1) { 2 }
+  bar
+}
+assert_equal '[1, 2]', %q{
+  def foo(a, &block) = [a, block.call]
+  def bar = foo(1) { 2 }
+  bar
+}
+
+# opt_send_without_block (VM_METHOD_TYPE_IVAR)
+assert_equal 'foo', %q{
+  class Foo
+    attr_reader :foo
+
+    def initialize
+      @foo = "foo"
+    end
+  end
+  Foo.new.foo
+}
+
+# opt_send_without_block (VM_METHOD_TYPE_OPTIMIZED)
+assert_equal 'foo', %q{
+  Foo = Struct.new(:bar)
+  Foo.new("bar").bar = "foo"
+}
+assert_equal 'foo', %q{
+  Foo = Struct.new(:bar)
+  Foo.new("foo").bar
+}
+
+# getblockparamproxy
+assert_equal 'foo', %q{
+  def foo(&block)
+    block.call
+  end
+  foo { "foo" }
+}
+
+# getblockparam
+assert_equal 'foo', %q{
+  def foo(&block)
+    block
+  end
+  foo { "foo" }.call
+}
+
+assert_equal '[1, 2]', %q{
+  def foo
+    x = [2]
+    [1, *x]
+  end
+
+  foo
+  foo
+}
+
+# respond_to? with changing symbol
+assert_equal 'false', %q{
+  def foo(name)
+    :sym.respond_to?(name)
+  end
+  foo(:to_s)
+  foo(:to_s)
+  foo(:not_exist)
+}
+
+# respond_to? with method being defined
+assert_equal 'true', %q{
+  def foo
+    :sym.respond_to?(:not_yet_defined)
+  end
+  foo
+  foo
+  module Kernel
+    def not_yet_defined = true
+  end
+  foo
+}
+
+# respond_to? with undef method
+assert_equal 'false', %q{
+  module Kernel
+    def to_be_removed = true
+  end
+  def foo
+    :sym.respond_to?(:to_be_removed)
+  end
+  foo
+  foo
+  class Object
+    undef_method :to_be_removed
+  end
+  foo
+}
+
+# respond_to? with respond_to_missing?
+assert_equal 'true', %q{
+  class Foo
+  end
+  def foo(x)
+    x.respond_to?(:bar)
+  end
+  foo(Foo.new)
+  foo(Foo.new)
+  class Foo
+    def respond_to_missing?(*) = true
+  end
+  foo(Foo.new)
+}
+
+# bmethod
+assert_equal '[1, 2, 3]', %q{
+  one = 1
+  define_method(:foo) do
+    one
+  end
+
+  3.times.map { |i| foo + i }
+}
+
+# return inside bmethod
+assert_equal 'ok', %q{
+  define_method(:foo) do
+    1.tap { return :ok }
+  end
+
+  foo
+}
+
+# bmethod optional and keywords
+assert_equal '[[1, nil, 2]]', %q{
+  define_method(:opt_and_kwargs) do |a = {}, b: nil, c: nil|
+    [a, b, c]
+  end
+
+  5.times.map { opt_and_kwargs(1, c: 2) }.uniq
+}
+
+# bmethod with forwarded block
+assert_equal '2', %q{
+  define_method(:foo) do |&block|
+    block.call
+  end
+
+  def bar(&block)
+    foo(&block)
+  end
+
+  bar { 1 }
+  bar { 2 }
+}
+
+# bmethod with forwarded block and arguments
+assert_equal '5', %q{
+  define_method(:foo) do |n, &block|
+    n + block.call
+  end
+
+  def bar(n, &block)
+    foo(n, &block)
+  end
+
+  bar(0) { 1 }
+  bar(3) { 2 }
+}
+
+# bmethod with forwarded unwanted block
+assert_equal '1', %q{
+  one = 1
+  define_method(:foo) do
+    one
+  end
+
+  def bar(&block)
+    foo(&block)
+  end
+
+  bar { }
+  bar { }
+}
+
+# test for return stub lifetime issue
+assert_equal '1', %q{
+  def foo(n)
+    if n == 2
+      return 1.times { Object.define_method(:foo) {} }
+    end
+
+    foo(n + 1)
+  end
+
+  foo(1)
+}
+
+# case-when with redefined ===
+assert_equal 'ok', %q{
+  class Symbol
+    def ===(a)
+      true
+    end
+  end
+
+  def cw(arg)
+    case arg
+    when :b
+      :ok
+    when 4
+      :ng
+    end
+  end
+
+  cw(4)
+}
+
+assert_normal_exit %{
+  class Bug20997
+    def foo(&) = self.class.name(&)
+
+    new.foo
+  end
+}
diff --git a/bootstraptest/test_yjit_rust_port.rb b/bootstraptest/test_yjit_rust_port.rb
new file mode 100644
index 0000000000..e399e0e49e
--- /dev/null
+++ b/bootstraptest/test_yjit_rust_port.rb
@@ -0,0 +1,422 @@
+# Simple tests that we know we can pass
+# To keep track of what we got working during the Rust port
+# And avoid breaking/losing functionality
+#
+# Say "Thread" here to dodge WASM CI check. We use ractors here
+# which WASM doesn't support and it only greps for "Thread".
+
+# Test for opt_mod
+assert_equal '2', %q{
+  def mod(a, b)
+    a % b
+  end
+
+  mod(7, 5)
+  mod(7, 5)
+}
+
+# Test for opt_mult
+assert_equal '12', %q{
+  def mult(a, b)
+    a * b
+  end
+
+  mult(6, 2)
+  mult(6, 2)
+}
+
+# Test for opt_div
+assert_equal '3', %q{
+  def div(a, b)
+    a / b
+  end
+
+  div(6, 2)
+  div(6, 2)
+}
+
+assert_equal '5', %q{
+  def plus(a, b)
+    a + b
+  end
+
+  plus(3, 2)
+}
+
+assert_equal '1', %q{
+  def foo(a, b)
+    a - b
+  end
+
+  foo(3, 2)
+}
+
+assert_equal 'true', %q{
+  def foo(a, b)
+    a < b
+  end
+
+  foo(2, 3)
+}
+
+# Bitwise left shift
+assert_equal '4', %q{
+  def foo(a, b)
+    1 << 2
+  end
+
+  foo(1, 2)
+}
+
+assert_equal '-7', %q{
+  def foo(a, b)
+    -7
+  end
+
+  foo(1, 2)
+}
+
+# Putstring
+assert_equal 'foo', %q{
+  def foo(a, b)
+    "foo"
+  end
+
+  foo(1, 2)
+}
+
+assert_equal '-6', %q{
+  def foo(a, b)
+    a + -7
+  end
+
+  foo(1, 2)
+}
+
+assert_equal 'true', %q{
+  def foo(a, b)
+    a == b
+  end
+
+  foo(3, 3)
+}
+
+assert_equal 'true', %q{
+  def foo(a, b)
+    a < b
+  end
+
+  foo(3, 5)
+}
+
+assert_equal '777', %q{
+  def foo(a)
+    if a
+      777
+    else
+      333
+    end
+  end
+
+  foo(true)
+}
+
+assert_equal '5', %q{
+  def foo(a, b)
+    while a < b
+      a += 1
+    end
+    a
+  end
+
+  foo(1, 5)
+}
+
+# opt_aref
+assert_equal '2', %q{
+  def foo(a, b)
+    a[b]
+  end
+
+  foo([0, 1, 2], 2)
+}
+
+# Simple function calls with 0, 1, 2 arguments
+assert_equal '-2', %q{
+  def bar()
+    -2
+  end
+
+  def foo(a, b)
+    bar()
+  end
+
+  foo(3, 2)
+}
+assert_equal '2', %q{
+  def bar(a)
+    a
+  end
+
+  def foo(a, b)
+    bar(b)
+  end
+
+  foo(3, 2)
+}
+assert_equal '1', %q{
+  def bar(a, b)
+    a - b
+  end
+
+  def foo(a, b)
+    bar(a, b)
+  end
+
+  foo(3, 2)
+}
+
+# Regression test for assembler bug
+assert_equal '1', %q{
+  def check_index(index)
+    if 0x40000000 < index
+        return -1
+    end
+    1
+  end
+
+  check_index 2
+}
+
+# Setivar test
+assert_equal '2', %q{
+  class Klass
+    attr_accessor :a
+
+    def set()
+        @a = 2
+    end
+
+    def get()
+        @a
+    end
+  end
+
+  o = Klass.new
+  o.set()
+  o.a
+}
+
+# Regression for putobject bug
+assert_equal '1.5', %q{
+  def foo(x)
+    x
+  end
+
+  def bar
+    foo(1.5)
+  end
+
+  bar()
+}
+
+# Getivar with an extended ivar table
+assert_equal '3', %q{
+  class Foo
+    def initialize
+      @x1 = 1
+      @x2 = 1
+      @x3 = 1
+      @x4 = 3
+    end
+
+    def bar
+      @x4
+    end
+  end
+
+  f = Foo.new
+  f.bar
+}
+
+assert_equal 'true', %q{
+  x = [[false, true]]
+  for i, j in x
+    ;
+  end
+  j
+}
+
+# Regression for getivar
+assert_equal '[nil]', %q{
+  [TrueClass].each do |klass|
+    klass.class_eval("def foo = @foo")
+  end
+
+  [true].map do |instance|
+    instance.foo
+  end
+}
+
+# Regression for send
+assert_equal 'ok', %q{
+  def bar(baz: 2)
+    baz
+  end
+
+  def foo
+    bar(1, baz: 123)
+  end
+
+  begin
+    foo
+    foo
+  rescue ArgumentError => e
+    print "ok"
+  end
+}
+
+# Array access regression test
+assert_equal '[0, 1, 2, 3, 4, 5]', %q{
+  def expandarray_useless_splat
+    arr = [0, 1, 2, 3, 4, 5]
+    a, * = arr
+  end
+
+  expandarray_useless_splat
+}
+
+# Make sure we're correctly reading RStruct's as.ary union for embedded RStructs
+assert_equal '3,12', %q{
+  pt_struct = Struct.new(:x, :y)
+  p = pt_struct.new(3, 12)
+  def pt_inspect(pt)
+    "#{pt.x},#{pt.y}"
+  end
+
+  # Make sure pt_inspect is JITted
+  10.times { pt_inspect(p) }
+
+  # Make sure it's returning '3,12' instead of e.g. '3,false'
+  pt_inspect(p)
+}
+
+assert_equal '2', %q{
+  def foo(s)
+    s.foo
+  end
+
+  S = Struct.new(:foo)
+  foo(S.new(1))
+  foo(S.new(2))
+}
+
+# Try to compile new method while OOM
+assert_equal 'ok', %q{
+  def foo
+    :ok
+  end
+
+  RubyVM::YJIT.simulate_oom! if defined?(RubyVM::YJIT)
+
+  foo
+}
+
+# test hitting a branch stub when out of memory
+assert_equal 'ok', %q{
+  def nimai(jita)
+    if jita
+      :ng
+    else
+      :ok
+    end
+  end
+
+  nimai(true)
+  nimai(true)
+
+  RubyVM::YJIT.simulate_oom! if defined?(RubyVM::YJIT)
+
+  nimai(false)
+}
+
+# Ractor.current returns a current ractor
+assert_equal 'Ractor', %q{
+  Ractor.current.class
+}
+
+# Ractor.new returns new Ractor
+assert_equal 'Ractor', %q{
+  Ractor.new{}.class
+}
+
+# Ractor.allocate is not supported
+assert_equal "[:ok, :ok]", %q{
+  rs = []
+  begin
+    Ractor.allocate
+  rescue => e
+    rs << :ok if e.message == 'allocator undefined for Ractor'
+  end
+
+  begin
+    Ractor.new{}.dup
+  rescue
+    rs << :ok if e.message == 'allocator undefined for Ractor'
+  end
+
+  rs
+}
+
+# A return value of a Ractor block will be a message from the Ractor.
+assert_equal 'ok', %q{
+  # join
+  r = Ractor.new do
+    'ok'
+  end
+  r.take
+}
+
+# Passed arguments to Ractor.new will be a block parameter
+# The values are passed with Ractor-communication pass.
+assert_equal 'ok', %q{
+  # ping-pong with arg
+  r = Ractor.new 'ok' do |msg|
+    msg
+  end
+  r.take
+}
+
+# Pass multiple arguments to Ractor.new
+assert_equal 'ok', %q{
+  # ping-pong with two args
+  r =  Ractor.new 'ping', 'pong' do |msg, msg2|
+    [msg, msg2]
+  end
+  'ok' if r.take == ['ping', 'pong']
+}
+
+# Ractor#send passes an object with copy to a Ractor
+# and Ractor.receive in the Ractor block can receive the passed value.
+assert_equal 'ok', %q{
+  r = Ractor.new do
+    msg = Ractor.receive
+  end
+  r.send 'ok'
+  r.take
+}
+
+assert_equal '[1, 2, 3]', %q{
+  def foo(arr)
+    arr << 1
+    arr << 2
+    arr << 3
+    arr
+  end
+
+  def bar()
+    foo([])
+  end
+
+  bar()
+}
diff --git a/builtin.h b/builtin.h
index 96339afdb5..38ad5a1629 100644
--- a/builtin.h
+++ b/builtin.h
@@ -13,11 +13,11 @@ struct rb_builtin_function {
     const char * const name;
 
     // for jit
-    void (*compiler)(FILE *, long, unsigned, bool);
+    void (*compiler)(VALUE, long, unsigned, bool);
 };
 
 #define RB_BUILTIN_FUNCTION(_i, _name, _fname, _arity, _compiler) {\
-  .name = #_name, \
+  .name = _i < 0 ? NULL : #_name, \
   .func_ptr = (void *)_fname, \
   .argc = _arity, \
   .index = _i, \
@@ -33,28 +33,65 @@ typedef struct rb_execution_context_struct rb_execution_context_t;
 
 /* The following code is generated by the following Ruby script:
 
+typedef = proc {|i, args|
+  "typedef VALUE (*rb_builtin_arity#{i}_function_type)(rb_execution_context_t *ec, VALUE self#{args});"
+}
+puts typedef[0, ""]
+(1..15).each {|i|
+  puts typedef[i, ",\n        " + (0...i).map{"VALUE"}.join(", ")]
+}
 16.times{|i|
-  args = (i > 0 ? ', ' : '') + (0...i).map{"VALUE"}.join(', ')
-  puts "static inline void rb_builtin_function_check_arity#{i}(VALUE (*f)(rb_execution_context_t *ec, VALUE self#{args})){}"
+  puts "static inline void rb_builtin_function_check_arity#{i}(rb_builtin_arity#{i}_function_type f){}"
 }
 */
 
-static inline void rb_builtin_function_check_arity0(VALUE (*f)(rb_execution_context_t *ec, VALUE self)){}
-static inline void rb_builtin_function_check_arity1(VALUE (*f)(rb_execution_context_t *ec, VALUE self, VALUE)){}
-static inline void rb_builtin_function_check_arity2(VALUE (*f)(rb_execution_context_t *ec, VALUE self, VALUE, VALUE)){}
-static inline void rb_builtin_function_check_arity3(VALUE (*f)(rb_execution_context_t *ec, VALUE self, VALUE, VALUE, VALUE)){}
-static inline void rb_builtin_function_check_arity4(VALUE (*f)(rb_execution_context_t *ec, VALUE self, VALUE, VALUE, VALUE, VALUE)){}
-static inline void rb_builtin_function_check_arity5(VALUE (*f)(rb_execution_context_t *ec, VALUE self, VALUE, VALUE, VALUE, VALUE, VALUE)){}
-static inline void rb_builtin_function_check_arity6(VALUE (*f)(rb_execution_context_t *ec, VALUE self, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE)){}
-static inline void rb_builtin_function_check_arity7(VALUE (*f)(rb_execution_context_t *ec, VALUE self, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE)){}
-static inline void rb_builtin_function_check_arity8(VALUE (*f)(rb_execution_context_t *ec, VALUE self, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE)){}
-static inline void rb_builtin_function_check_arity9(VALUE (*f)(rb_execution_context_t *ec, VALUE self, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE)){}
-static inline void rb_builtin_function_check_arity10(VALUE (*f)(rb_execution_context_t *ec, VALUE self, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE)){}
-static inline void rb_builtin_function_check_arity11(VALUE (*f)(rb_execution_context_t *ec, VALUE self, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE)){}
-static inline void rb_builtin_function_check_arity12(VALUE (*f)(rb_execution_context_t *ec, VALUE self, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE)){}
-static inline void rb_builtin_function_check_arity13(VALUE (*f)(rb_execution_context_t *ec, VALUE self, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE)){}
-static inline void rb_builtin_function_check_arity14(VALUE (*f)(rb_execution_context_t *ec, VALUE self, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE)){}
-static inline void rb_builtin_function_check_arity15(VALUE (*f)(rb_execution_context_t *ec, VALUE self, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE)){}
+typedef VALUE (*rb_builtin_arity0_function_type)(rb_execution_context_t *ec, VALUE self);
+typedef VALUE (*rb_builtin_arity1_function_type)(rb_execution_context_t *ec, VALUE self,
+        VALUE);
+typedef VALUE (*rb_builtin_arity2_function_type)(rb_execution_context_t *ec, VALUE self,
+        VALUE, VALUE);
+typedef VALUE (*rb_builtin_arity3_function_type)(rb_execution_context_t *ec, VALUE self,
+        VALUE, VALUE, VALUE);
+typedef VALUE (*rb_builtin_arity4_function_type)(rb_execution_context_t *ec, VALUE self,
+        VALUE, VALUE, VALUE, VALUE);
+typedef VALUE (*rb_builtin_arity5_function_type)(rb_execution_context_t *ec, VALUE self,
+        VALUE, VALUE, VALUE, VALUE, VALUE);
+typedef VALUE (*rb_builtin_arity6_function_type)(rb_execution_context_t *ec, VALUE self,
+        VALUE, VALUE, VALUE, VALUE, VALUE, VALUE);
+typedef VALUE (*rb_builtin_arity7_function_type)(rb_execution_context_t *ec, VALUE self,
+        VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE);
+typedef VALUE (*rb_builtin_arity8_function_type)(rb_execution_context_t *ec, VALUE self,
+        VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE);
+typedef VALUE (*rb_builtin_arity9_function_type)(rb_execution_context_t *ec, VALUE self,
+        VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE);
+typedef VALUE (*rb_builtin_arity10_function_type)(rb_execution_context_t *ec, VALUE self,
+        VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE);
+typedef VALUE (*rb_builtin_arity11_function_type)(rb_execution_context_t *ec, VALUE self,
+        VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE);
+typedef VALUE (*rb_builtin_arity12_function_type)(rb_execution_context_t *ec, VALUE self,
+        VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE);
+typedef VALUE (*rb_builtin_arity13_function_type)(rb_execution_context_t *ec, VALUE self,
+        VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE);
+typedef VALUE (*rb_builtin_arity14_function_type)(rb_execution_context_t *ec, VALUE self,
+        VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE);
+typedef VALUE (*rb_builtin_arity15_function_type)(rb_execution_context_t *ec, VALUE self,
+        VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE, VALUE);
+static inline void rb_builtin_function_check_arity0(rb_builtin_arity0_function_type f){}
+static inline void rb_builtin_function_check_arity1(rb_builtin_arity1_function_type f){}
+static inline void rb_builtin_function_check_arity2(rb_builtin_arity2_function_type f){}
+static inline void rb_builtin_function_check_arity3(rb_builtin_arity3_function_type f){}
+static inline void rb_builtin_function_check_arity4(rb_builtin_arity4_function_type f){}
+static inline void rb_builtin_function_check_arity5(rb_builtin_arity5_function_type f){}
+static inline void rb_builtin_function_check_arity6(rb_builtin_arity6_function_type f){}
+static inline void rb_builtin_function_check_arity7(rb_builtin_arity7_function_type f){}
+static inline void rb_builtin_function_check_arity8(rb_builtin_arity8_function_type f){}
+static inline void rb_builtin_function_check_arity9(rb_builtin_arity9_function_type f){}
+static inline void rb_builtin_function_check_arity10(rb_builtin_arity10_function_type f){}
+static inline void rb_builtin_function_check_arity11(rb_builtin_arity11_function_type f){}
+static inline void rb_builtin_function_check_arity12(rb_builtin_arity12_function_type f){}
+static inline void rb_builtin_function_check_arity13(rb_builtin_arity13_function_type f){}
+static inline void rb_builtin_function_check_arity14(rb_builtin_arity14_function_type f){}
+static inline void rb_builtin_function_check_arity15(rb_builtin_arity15_function_type f){}
 
 PUREFUNC(VALUE rb_vm_lvar_exposed(rb_execution_context_t *ec, int index));
 VALUE rb_vm_lvar_exposed(rb_execution_context_t *ec, int index);
diff --git a/ccan/check_type/check_type.h b/ccan/check_type/check_type.h
index e795ad71d0..659e1a5a83 100644
--- a/ccan/check_type/check_type.h
+++ b/ccan/check_type/check_type.h
@@ -44,7 +44,7 @@
  *		 ((encl_type *)						\
  *		  ((char *)(mbr_ptr) - offsetof(enclosing_type, mbr))))
  */
-#if HAVE_TYPEOF
+#if defined(HAVE_TYPEOF) && HAVE_TYPEOF
 #define ccan_check_type(expr, type)			\
 	((typeof(expr) *)0 != (type *)0)
 
diff --git a/ccan/container_of/container_of.h b/ccan/container_of/container_of.h
index b30c347d57..872bb6ea6e 100644
--- a/ccan/container_of/container_of.h
+++ b/ccan/container_of/container_of.h
@@ -112,7 +112,7 @@ static inline char *container_of_or_null_(void *member_ptr, size_t offset)
  *		return i;
  *	}
  */
-#if HAVE_TYPEOF
+#if defined(HAVE_TYPEOF) && HAVE_TYPEOF
 #define ccan_container_of_var(member_ptr, container_var, member) \
 	ccan_container_of(member_ptr, typeof(*container_var), member)
 #else
@@ -131,7 +131,7 @@ static inline char *container_of_or_null_(void *member_ptr, size_t offset)
  * structure memory layout.
  *
  */
-#if HAVE_TYPEOF
+#if defined(HAVE_TYPEOF) && HAVE_TYPEOF
 #define ccan_container_off_var(var, member)		\
 	ccan_container_off(typeof(*var), member)
 #else
diff --git a/ccan/list/list.h b/ccan/list/list.h
index 91787bfdb3..30b2af04e9 100644
--- a/ccan/list/list.h
+++ b/ccan/list/list.h
@@ -770,7 +770,7 @@ static inline struct ccan_list_node *ccan_list_node_from_off_(void *ptr, size_t
 	(ccan_container_off_var(var, member) +		\
 	 ccan_check_type(var->member, struct ccan_list_node))
 
-#if HAVE_TYPEOF
+#if defined(HAVE_TYPEOF) && HAVE_TYPEOF
 #define ccan_list_typeof(var) typeof(var)
 #else
 #define ccan_list_typeof(var) void *
diff --git a/class.c b/class.c
index 39899d5e05..cf0b7b821f 100644
--- a/class.c
+++ b/class.c
@@ -64,7 +64,7 @@ push_subclass_entry_to_list(VALUE super, VALUE klass)
 void
 rb_class_subclass_add(VALUE super, VALUE klass)
 {
-    if (super && super != Qundef) {
+    if (super && !UNDEF_P(super)) {
         rb_subclass_entry_t *entry = push_subclass_entry_to_list(super, klass);
         RCLASS_SUBCLASS_ENTRY(klass) = entry;
     }
@@ -106,7 +106,7 @@ rb_class_remove_from_super_subclasses(VALUE klass)
             next->prev = prev;
         }
 
-	xfree(entry);
+        xfree(entry);
     }
 
     RCLASS_SUBCLASS_ENTRY(klass) = NULL;
@@ -123,11 +123,11 @@ rb_class_remove_from_module_subclasses(VALUE klass)
         if (prev) {
             prev->next = next;
         }
-	if (next) {
+        if (next) {
             next->prev = prev;
-	}
+        }
 
-	xfree(entry);
+        xfree(entry);
     }
 
     RCLASS_MODULE_SUBCLASS_ENTRY(klass) = NULL;
@@ -148,11 +148,11 @@ rb_class_foreach_subclass(VALUE klass, void (*f)(VALUE, VALUE), VALUE arg)
     /* do not be tempted to simplify this loop into a for loop, the order of
        operations is important here if `f` modifies the linked list */
     while (cur) {
-	VALUE curklass = cur->klass;
-	cur = cur->next;
+        VALUE curklass = cur->klass;
+        cur = cur->next;
         // do not trigger GC during f, otherwise the cur will become
         // a dangling pointer if the subclass is collected
-	f(curklass, arg);
+        f(curklass, arg);
     }
 }
 
@@ -197,7 +197,7 @@ class_alloc(VALUE flags, VALUE klass)
 {
     size_t alloc_size = sizeof(struct RClass);
 
-#if USE_RVARGC
+#if RCLASS_EXT_EMBEDDED
     alloc_size += sizeof(rb_classext_t);
 #endif
 
@@ -206,17 +206,13 @@ class_alloc(VALUE flags, VALUE klass)
     if (RGENGC_WB_PROTECTED_CLASS) flags |= FL_WB_PROTECTED;
     RVARGC_NEWOBJ_OF(obj, struct RClass, klass, flags, alloc_size);
 
-#if USE_RVARGC
+#if RCLASS_EXT_EMBEDDED
     memset(RCLASS_EXT(obj), 0, sizeof(rb_classext_t));
-# if SIZEOF_SERIAL_T != SIZEOF_VALUE
-    RCLASS(obj)->class_serial_ptr = ZALLOC(rb_serial_t);
-# endif
 #else
     obj->ptr = ZALLOC(rb_classext_t);
 #endif
 
     /* ZALLOC
-      RCLASS_IV_TBL(obj) = 0;
       RCLASS_CONST_TBL(obj) = 0;
       RCLASS_M_TBL(obj) = 0;
       RCLASS_IV_INDEX_TBL(obj) = 0;
@@ -226,7 +222,6 @@ class_alloc(VALUE flags, VALUE klass)
       RCLASS_MODULE_SUBCLASSES(obj) = NULL;
      */
     RCLASS_SET_ORIGIN((VALUE)obj, (VALUE)obj);
-    RCLASS_SERIAL(obj) = rb_next_class_serial();
     RB_OBJ_WRITE(obj, &RCLASS_REFINED_CLASS(obj), Qnil);
     RCLASS_ALLOCATOR(obj) = 0;
 
@@ -282,7 +277,7 @@ rb_class_update_superclasses(VALUE klass)
     VALUE super = RCLASS_SUPER(klass);
 
     if (!RB_TYPE_P(klass, T_CLASS)) return;
-    if (super == Qundef) return;
+    if (UNDEF_P(super)) return;
 
     // If the superclass array is already built
     if (RCLASS_SUPERCLASSES(klass))
@@ -316,13 +311,13 @@ rb_check_inheritable(VALUE super)
 {
     if (!RB_TYPE_P(super, T_CLASS)) {
         rb_raise(rb_eTypeError, "superclass must be an instance of Class (given an instance of %"PRIsVALUE")",
-		 rb_obj_class(super));
+                 rb_obj_class(super));
     }
     if (RBASIC(super)->flags & FL_SINGLETON) {
-	rb_raise(rb_eTypeError, "can't make subclass of singleton class");
+        rb_raise(rb_eTypeError, "can't make subclass of singleton class");
     }
     if (super == rb_cClass) {
-	rb_raise(rb_eTypeError, "can't make subclass of Class");
+        rb_raise(rb_eTypeError, "can't make subclass of Class");
     }
 }
 
@@ -331,7 +326,13 @@ rb_class_new(VALUE super)
 {
     Check_Type(super, T_CLASS);
     rb_check_inheritable(super);
-    return rb_class_boot(super);
+    VALUE klass = rb_class_boot(super);
+
+    if (super != rb_cObject && super != rb_cBasicObject) {
+        RCLASS_EXT(klass)->max_iv_count = RCLASS_EXT(super)->max_iv_count;
+    }
+
+    return klass;
 }
 
 VALUE
@@ -344,12 +345,12 @@ static void
 clone_method(VALUE old_klass, VALUE new_klass, ID mid, const rb_method_entry_t *me)
 {
     if (me->def->type == VM_METHOD_TYPE_ISEQ) {
-	rb_cref_t *new_cref;
-	rb_vm_rewrite_cref(me->def->body.iseq.cref, old_klass, new_klass, &new_cref);
-	rb_add_method_iseq(new_klass, mid, me->def->body.iseq.iseqptr, new_cref, METHOD_ENTRY_VISI(me));
+        rb_cref_t *new_cref;
+        rb_vm_rewrite_cref(me->def->body.iseq.cref, old_klass, new_klass, &new_cref);
+        rb_add_method_iseq(new_klass, mid, me->def->body.iseq.iseqptr, new_cref, METHOD_ENTRY_VISI(me));
     }
     else {
-	rb_method_entry_set(new_klass, mid, me, METHOD_ENTRY_VISI(me));
+        rb_method_entry_set(new_klass, mid, me, METHOD_ENTRY_VISI(me));
     }
 }
 
@@ -393,45 +394,74 @@ static void
 class_init_copy_check(VALUE clone, VALUE orig)
 {
     if (orig == rb_cBasicObject) {
-	rb_raise(rb_eTypeError, "can't copy the root class");
+        rb_raise(rb_eTypeError, "can't copy the root class");
     }
     if (RCLASS_SUPER(clone) != 0 || clone == rb_cBasicObject) {
-	rb_raise(rb_eTypeError, "already initialized class");
+        rb_raise(rb_eTypeError, "already initialized class");
     }
     if (FL_TEST(orig, FL_SINGLETON)) {
-	rb_raise(rb_eTypeError, "can't copy singleton class");
+        rb_raise(rb_eTypeError, "can't copy singleton class");
     }
 }
 
+struct cvc_table_copy_ctx {
+    VALUE clone;
+    struct rb_id_table * new_table;
+};
+
+static enum rb_id_table_iterator_result
+cvc_table_copy(ID id, VALUE val, void *data) {
+    struct cvc_table_copy_ctx *ctx = (struct cvc_table_copy_ctx *)data;
+    struct rb_cvar_class_tbl_entry * orig_entry;
+    orig_entry = (struct rb_cvar_class_tbl_entry *)val;
+
+    struct rb_cvar_class_tbl_entry *ent;
+
+    ent = ALLOC(struct rb_cvar_class_tbl_entry);
+    ent->class_value = ctx->clone;
+    ent->cref = orig_entry->cref;
+    ent->global_cvar_state = orig_entry->global_cvar_state;
+    rb_id_table_insert(ctx->new_table, id, (VALUE)ent);
+
+    RB_OBJ_WRITTEN(ctx->clone, Qundef, ent->cref);
+
+    return ID_TABLE_CONTINUE;
+}
+
 static void
 copy_tables(VALUE clone, VALUE orig)
 {
-    if (RCLASS_IV_TBL(clone)) {
-	st_free_table(RCLASS_IV_TBL(clone));
-	RCLASS_IV_TBL(clone) = 0;
-    }
     if (RCLASS_CONST_TBL(clone)) {
-	rb_free_const_table(RCLASS_CONST_TBL(clone));
-	RCLASS_CONST_TBL(clone) = 0;
+        rb_free_const_table(RCLASS_CONST_TBL(clone));
+        RCLASS_CONST_TBL(clone) = 0;
     }
+    if (RCLASS_CVC_TBL(orig)) {
+        struct rb_id_table *rb_cvc_tbl = RCLASS_CVC_TBL(orig);
+        struct rb_id_table *rb_cvc_tbl_dup = rb_id_table_create(rb_id_table_size(rb_cvc_tbl));
+
+        struct cvc_table_copy_ctx ctx;
+        ctx.clone = clone;
+        ctx.new_table = rb_cvc_tbl_dup;
+        rb_id_table_foreach(rb_cvc_tbl, cvc_table_copy, &ctx);
+        RCLASS_CVC_TBL(clone) = rb_cvc_tbl_dup;
+    }
+    rb_id_table_free(RCLASS_M_TBL(clone));
     RCLASS_M_TBL(clone) = 0;
-    if (RCLASS_IV_TBL(orig)) {
-	st_data_t id;
+    if (!RB_TYPE_P(clone, T_ICLASS)) {
+        st_data_t id;
 
-	rb_iv_tbl_copy(clone, orig);
-	CONST_ID(id, "__tmp_classpath__");
-	st_delete(RCLASS_IV_TBL(clone), &id, 0);
-	CONST_ID(id, "__classpath__");
-	st_delete(RCLASS_IV_TBL(clone), &id, 0);
-	CONST_ID(id, "__classid__");
-	st_delete(RCLASS_IV_TBL(clone), &id, 0);
+        rb_iv_tbl_copy(clone, orig);
+        CONST_ID(id, "__tmp_classpath__");
+        rb_attr_delete(clone, id);
+        CONST_ID(id, "__classpath__");
+        rb_attr_delete(clone, id);
     }
     if (RCLASS_CONST_TBL(orig)) {
-	struct clone_const_arg arg;
+        struct clone_const_arg arg;
 
-	arg.tbl = RCLASS_CONST_TBL(clone) = rb_id_table_create(0);
-	arg.klass = clone;
-	rb_id_table_foreach(RCLASS_CONST_TBL(orig), clone_const_i, &arg);
+        arg.tbl = RCLASS_CONST_TBL(clone) = rb_id_table_create(0);
+        arg.klass = clone;
+        rb_id_table_foreach(RCLASS_CONST_TBL(orig), clone_const_i, &arg);
     }
 }
 
@@ -493,11 +523,11 @@ rb_mod_init_copy(VALUE clone, VALUE orig)
     RCLASS_ALLOCATOR(clone) = RCLASS_ALLOCATOR(orig);
     copy_tables(clone, orig);
     if (RCLASS_M_TBL(orig)) {
-	struct clone_method_arg arg;
-	arg.old_klass = orig;
-	arg.new_klass = clone;
-	RCLASS_M_TBL_INIT(clone);
-	rb_id_table_foreach(RCLASS_M_TBL(orig), clone_method_i, &arg);
+        struct clone_method_arg arg;
+        arg.old_klass = orig;
+        arg.new_klass = clone;
+        RCLASS_M_TBL_INIT(clone);
+        rb_id_table_foreach(RCLASS_M_TBL(orig), clone_method_i, &arg);
     }
 
     if (RCLASS_ORIGIN(orig) == orig) {
@@ -507,7 +537,7 @@ rb_mod_init_copy(VALUE clone, VALUE orig)
         VALUE p = RCLASS_SUPER(orig);
         VALUE orig_origin = RCLASS_ORIGIN(orig);
         VALUE prev_clone_p = clone;
-        VALUE origin_stack = rb_ary_tmp_new(2);
+        VALUE origin_stack = rb_ary_hidden_new(2);
         VALUE origin[2];
         VALUE clone_p = 0;
         long origin_len;
@@ -526,7 +556,6 @@ rb_mod_init_copy(VALUE clone, VALUE orig)
             prev_clone_p = clone_p;
             RCLASS_M_TBL(clone_p) = RCLASS_M_TBL(p);
             RCLASS_CONST_TBL(clone_p) = RCLASS_CONST_TBL(p);
-            RCLASS_IV_TBL(clone_p) = RCLASS_IV_TBL(p);
             RCLASS_ALLOCATOR(clone_p) = RCLASS_ALLOCATOR(p);
             if (RB_TYPE_P(clone, T_CLASS)) {
                 RCLASS_SET_INCLUDER(clone_p, clone);
@@ -567,6 +596,8 @@ rb_mod_init_copy(VALUE clone, VALUE orig)
         else {
             rb_bug("no origin for class that has origin");
         }
+
+        rb_class_update_superclasses(clone);
     }
 
     return clone;
@@ -593,49 +624,47 @@ rb_singleton_class_clone_and_attach(VALUE obj, VALUE attach)
         return klass;
     }
     else {
-	/* copy singleton(unnamed) class */
+        /* copy singleton(unnamed) class */
         bool klass_of_clone_is_new;
-	VALUE clone = class_alloc(RBASIC(klass)->flags, 0);
+        VALUE clone = class_alloc(RBASIC(klass)->flags, 0);
 
-	if (BUILTIN_TYPE(obj) == T_CLASS) {
+        if (BUILTIN_TYPE(obj) == T_CLASS) {
             klass_of_clone_is_new = true;
-	    RBASIC_SET_CLASS(clone, clone);
-	}
-	else {
+            RBASIC_SET_CLASS(clone, clone);
+        }
+        else {
             VALUE klass_metaclass_clone = rb_singleton_class_clone(klass);
             // When `METACLASS_OF(klass) == klass_metaclass_clone`, it means the
             // recursive call did not clone `METACLASS_OF(klass)`.
             klass_of_clone_is_new = (METACLASS_OF(klass) != klass_metaclass_clone);
             RBASIC_SET_CLASS(clone, klass_metaclass_clone);
-	}
-
-	RCLASS_SET_SUPER(clone, RCLASS_SUPER(klass));
-	RCLASS_ALLOCATOR(clone) = RCLASS_ALLOCATOR(klass);
-	if (RCLASS_IV_TBL(klass)) {
-	    rb_iv_tbl_copy(clone, klass);
-	}
-	if (RCLASS_CONST_TBL(klass)) {
-	    struct clone_const_arg arg;
-	    arg.tbl = RCLASS_CONST_TBL(clone) = rb_id_table_create(0);
-	    arg.klass = clone;
-	    rb_id_table_foreach(RCLASS_CONST_TBL(klass), clone_const_i, &arg);
-	}
-	if (attach != Qundef) {
-	    rb_singleton_class_attached(clone, attach);
-	}
-	RCLASS_M_TBL_INIT(clone);
-	{
-	    struct clone_method_arg arg;
-	    arg.old_klass = klass;
-	    arg.new_klass = clone;
-	    rb_id_table_foreach(RCLASS_M_TBL(klass), clone_method_i, &arg);
-	}
+        }
+
+        RCLASS_SET_SUPER(clone, RCLASS_SUPER(klass));
+        RCLASS_ALLOCATOR(clone) = RCLASS_ALLOCATOR(klass);
+        rb_iv_tbl_copy(clone, klass);
+        if (RCLASS_CONST_TBL(klass)) {
+            struct clone_const_arg arg;
+            arg.tbl = RCLASS_CONST_TBL(clone) = rb_id_table_create(0);
+            arg.klass = clone;
+            rb_id_table_foreach(RCLASS_CONST_TBL(klass), clone_const_i, &arg);
+        }
+        if (!UNDEF_P(attach)) {
+            rb_singleton_class_attached(clone, attach);
+        }
+        RCLASS_M_TBL_INIT(clone);
+        {
+            struct clone_method_arg arg;
+            arg.old_klass = klass;
+            arg.new_klass = clone;
+            rb_id_table_foreach(RCLASS_M_TBL(klass), clone_method_i, &arg);
+        }
         if (klass_of_clone_is_new) {
             rb_singleton_class_attached(METACLASS_OF(clone), clone);
         }
-	FL_SET(clone, FL_SINGLETON);
+        FL_SET(clone, FL_SINGLETON);
 
-	return clone;
+        return clone;
     }
 }
 
@@ -643,7 +672,7 @@ void
 rb_singleton_class_attached(VALUE klass, VALUE obj)
 {
     if (FL_TEST(klass, FL_SINGLETON)) {
-	rb_class_ivar_set(klass, id_attached, obj);
+        rb_class_ivar_set(klass, id_attached, obj);
     }
 }
 
@@ -664,7 +693,7 @@ int
 rb_singleton_class_internal_p(VALUE sklass)
 {
     return (RB_TYPE_P(rb_attr_get(sklass, id_attached), T_CLASS) &&
-	    !rb_singleton_class_has_metaclass_p(sklass));
+            !rb_singleton_class_has_metaclass_p(sklass));
 }
 
 /*!
@@ -706,13 +735,13 @@ make_metaclass(VALUE klass)
     rb_singleton_class_attached(metaclass, klass);
 
     if (META_CLASS_OF_CLASS_CLASS_P(klass)) {
-	SET_METACLASS_OF(klass, metaclass);
-	SET_METACLASS_OF(metaclass, metaclass);
+        SET_METACLASS_OF(klass, metaclass);
+        SET_METACLASS_OF(metaclass, metaclass);
     }
     else {
-	VALUE tmp = METACLASS_OF(klass); /* for a meta^(n)-class klass, tmp is meta^(n)-class of Class class */
-	SET_METACLASS_OF(klass, metaclass);
-	SET_METACLASS_OF(metaclass, ENSURE_EIGENCLASS(tmp));
+        VALUE tmp = METACLASS_OF(klass); /* for a meta^(n)-class klass, tmp is meta^(n)-class of Class class */
+        SET_METACLASS_OF(klass, metaclass);
+        SET_METACLASS_OF(metaclass, ENSURE_EIGENCLASS(tmp));
     }
 
     super = RCLASS_SUPER(klass);
@@ -853,10 +882,10 @@ VALUE
 rb_make_metaclass(VALUE obj, VALUE unused)
 {
     if (BUILTIN_TYPE(obj) == T_CLASS) {
-	return make_metaclass(obj);
+        return make_metaclass(obj);
     }
     else {
-	return make_singleton_class(obj);
+        return make_singleton_class(obj);
     }
 }
 
@@ -898,21 +927,21 @@ rb_define_class(const char *name, VALUE super)
 
     id = rb_intern(name);
     if (rb_const_defined(rb_cObject, id)) {
-	klass = rb_const_get(rb_cObject, id);
-	if (!RB_TYPE_P(klass, T_CLASS)) {
-	    rb_raise(rb_eTypeError, "%s is not a class (%"PRIsVALUE")",
-		     name, rb_obj_class(klass));
-	}
-	if (rb_class_real(RCLASS_SUPER(klass)) != super) {
-	    rb_raise(rb_eTypeError, "superclass mismatch for class %s", name);
-	}
+        klass = rb_const_get(rb_cObject, id);
+        if (!RB_TYPE_P(klass, T_CLASS)) {
+            rb_raise(rb_eTypeError, "%s is not a class (%"PRIsVALUE")",
+                     name, rb_obj_class(klass));
+        }
+        if (rb_class_real(RCLASS_SUPER(klass)) != super) {
+            rb_raise(rb_eTypeError, "superclass mismatch for class %s", name);
+        }
 
         /* Class may have been defined in Ruby and not pin-rooted */
         rb_vm_add_root_module(klass);
-	return klass;
+        return klass;
     }
     if (!super) {
-	rb_raise(rb_eArgError, "no super class for `%s'", name);
+        rb_raise(rb_eArgError, "no super class for `%s'", name);
     }
     klass = rb_define_class_id(id, super);
     rb_vm_add_root_module(klass);
@@ -929,42 +958,47 @@ rb_define_class_under(VALUE outer, const char *name, VALUE super)
 }
 
 VALUE
-rb_define_class_id_under(VALUE outer, ID id, VALUE super)
+rb_define_class_id_under_no_pin(VALUE outer, ID id, VALUE super)
 {
     VALUE klass;
 
     if (rb_const_defined_at(outer, id)) {
-	klass = rb_const_get_at(outer, id);
-	if (!RB_TYPE_P(klass, T_CLASS)) {
-	    rb_raise(rb_eTypeError, "%"PRIsVALUE"::%"PRIsVALUE" is not a class"
-		     " (%"PRIsVALUE")",
-		     outer, rb_id2str(id), rb_obj_class(klass));
-	}
-	if (rb_class_real(RCLASS_SUPER(klass)) != super) {
-	    rb_raise(rb_eTypeError, "superclass mismatch for class "
-		     "%"PRIsVALUE"::%"PRIsVALUE""
-		     " (%"PRIsVALUE" is given but was %"PRIsVALUE")",
-		     outer, rb_id2str(id), RCLASS_SUPER(klass), super);
-	}
-        /* Class may have been defined in Ruby and not pin-rooted */
-        rb_vm_add_root_module(klass);
+        klass = rb_const_get_at(outer, id);
+        if (!RB_TYPE_P(klass, T_CLASS)) {
+            rb_raise(rb_eTypeError, "%"PRIsVALUE"::%"PRIsVALUE" is not a class"
+                     " (%"PRIsVALUE")",
+                     outer, rb_id2str(id), rb_obj_class(klass));
+        }
+        if (rb_class_real(RCLASS_SUPER(klass)) != super) {
+            rb_raise(rb_eTypeError, "superclass mismatch for class "
+                     "%"PRIsVALUE"::%"PRIsVALUE""
+                     " (%"PRIsVALUE" is given but was %"PRIsVALUE")",
+                     outer, rb_id2str(id), RCLASS_SUPER(klass), super);
+        }
 
-	return klass;
+        return klass;
     }
     if (!super) {
-	rb_raise(rb_eArgError, "no super class for `%"PRIsVALUE"::%"PRIsVALUE"'",
-		 rb_class_path(outer), rb_id2str(id));
+        rb_raise(rb_eArgError, "no super class for `%"PRIsVALUE"::%"PRIsVALUE"'",
+                 rb_class_path(outer), rb_id2str(id));
     }
     klass = rb_define_class_id(id, super);
     rb_set_class_path_string(klass, outer, rb_id2str(id));
     rb_const_set(outer, id, klass);
     rb_class_inherited(super, klass);
-    rb_vm_add_root_module(klass);
 
     return klass;
 }
 
 VALUE
+rb_define_class_id_under(VALUE outer, ID id, VALUE super)
+{
+    VALUE klass = rb_define_class_id_under_no_pin(outer, id, super);
+    rb_vm_add_root_module(klass);
+    return klass;
+}
+
+VALUE
 rb_module_s_alloc(VALUE klass)
 {
     VALUE mod = class_alloc(T_MODULE, klass);
@@ -1008,14 +1042,14 @@ rb_define_module(const char *name)
 
     id = rb_intern(name);
     if (rb_const_defined(rb_cObject, id)) {
-	module = rb_const_get(rb_cObject, id);
-	if (!RB_TYPE_P(module, T_MODULE)) {
-	    rb_raise(rb_eTypeError, "%s is not a module (%"PRIsVALUE")",
-		     name, rb_obj_class(module));
-	}
+        module = rb_const_get(rb_cObject, id);
+        if (!RB_TYPE_P(module, T_MODULE)) {
+            rb_raise(rb_eTypeError, "%s is not a module (%"PRIsVALUE")",
+                     name, rb_obj_class(module));
+        }
         /* Module may have been defined in Ruby and not pin-rooted */
         rb_vm_add_root_module(module);
-	return module;
+        return module;
     }
     module = rb_module_new();
     rb_vm_add_root_module(module);
@@ -1036,15 +1070,15 @@ rb_define_module_id_under(VALUE outer, ID id)
     VALUE module;
 
     if (rb_const_defined_at(outer, id)) {
-	module = rb_const_get_at(outer, id);
-	if (!RB_TYPE_P(module, T_MODULE)) {
-	    rb_raise(rb_eTypeError, "%"PRIsVALUE"::%"PRIsVALUE" is not a module"
-		     " (%"PRIsVALUE")",
-		     outer, rb_id2str(id), rb_obj_class(module));
-	}
+        module = rb_const_get_at(outer, id);
+        if (!RB_TYPE_P(module, T_MODULE)) {
+            rb_raise(rb_eTypeError, "%"PRIsVALUE"::%"PRIsVALUE" is not a module"
+                     " (%"PRIsVALUE")",
+                     outer, rb_id2str(id), rb_obj_class(module));
+        }
         /* Module may have been defined in Ruby and not pin-rooted */
         rb_gc_register_mark_object(module);
-	return module;
+        return module;
     }
     module = rb_module_new();
     rb_const_set(outer, id, module);
@@ -1063,16 +1097,13 @@ rb_include_class_new(VALUE module, VALUE super)
 
     RCLASS_SET_ORIGIN(klass, klass);
     if (BUILTIN_TYPE(module) == T_ICLASS) {
-	module = METACLASS_OF(module);
+        module = METACLASS_OF(module);
     }
     RUBY_ASSERT(!RB_TYPE_P(module, T_ICLASS));
-    if (!RCLASS_IV_TBL(module)) {
-	RCLASS_IV_TBL(module) = st_init_numtable();
-    }
     if (!RCLASS_CONST_TBL(module)) {
-	RCLASS_CONST_TBL(module) = rb_id_table_create(0);
+        RCLASS_CONST_TBL(module) = rb_id_table_create(0);
     }
-    RCLASS_IV_TBL(klass) = RCLASS_IV_TBL(module);
+
     RCLASS_CVC_TBL(klass) = RCLASS_CVC_TBL(module);
     RCLASS_CONST_TBL(klass) = RCLASS_CONST_TBL(module);
 
@@ -1091,7 +1122,7 @@ ensure_includable(VALUE klass, VALUE module)
     Check_Type(module, T_MODULE);
     rb_module_set_initialized(module);
     if (!NIL_P(rb_refinement_module_get_refined_class(module))) {
-	rb_raise(rb_eArgError, "refinement module is not allowed");
+        rb_raise(rb_eArgError, "refinement module is not allowed");
     }
 }
 
@@ -1104,7 +1135,7 @@ rb_include_module(VALUE klass, VALUE module)
 
     changed = include_modules_at(klass, RCLASS_ORIGIN(klass), module, TRUE);
     if (changed < 0)
-	rb_raise(rb_eArgError, "cyclic include detected");
+        rb_raise(rb_eArgError, "cyclic include detected");
 
     if (RB_TYPE_P(klass, T_MODULE)) {
         rb_subclass_entry_t *iclass = RCLASS_SUBCLASSES(klass);
@@ -1114,8 +1145,8 @@ rb_include_module(VALUE klass, VALUE module)
             iclass = iclass->next;
         }
 
-        int do_include = 1;
         while (iclass) {
+            int do_include = 1;
             VALUE check_class = iclass->klass;
             /* During lazy sweeping, iclass->klass could be a dead object that
              * has not yet been swept. */
@@ -1182,7 +1213,7 @@ static int
 do_include_modules_at(const VALUE klass, VALUE c, VALUE module, int search_super, bool check_cyclic)
 {
     VALUE p, iclass, origin_stack = 0;
-    int method_changed = 0, add_subclass;
+    int method_changed = 0;
     long origin_len;
     VALUE klass_origin = RCLASS_ORIGIN(klass);
     VALUE original_klass = klass;
@@ -1192,8 +1223,8 @@ do_include_modules_at(const VALUE klass, VALUE c, VALUE module, int search_super
 
     while (module) {
         int c_seen = FALSE;
-	int superclass_seen = FALSE;
-	struct rb_id_table *tbl;
+        int superclass_seen = FALSE;
+        struct rb_id_table *tbl;
 
         if (klass == c) {
             c_seen = TRUE;
@@ -1243,12 +1274,11 @@ do_include_modules_at(const VALUE klass, VALUE c, VALUE module, int search_super
         }
 
         // setup T_ICLASS for the include/prepend module
-	iclass = rb_include_class_new(module, super_class);
-	c = RCLASS_SET_SUPER(c, iclass);
+        iclass = rb_include_class_new(module, super_class);
+        c = RCLASS_SET_SUPER(c, iclass);
         RCLASS_SET_INCLUDER(iclass, klass);
-        add_subclass = TRUE;
         if (module != RCLASS_ORIGIN(module)) {
-            if (!origin_stack) origin_stack = rb_ary_tmp_new(2);
+            if (!origin_stack) origin_stack = rb_ary_hidden_new(2);
             VALUE origin[2] = {iclass, RCLASS_ORIGIN(module)};
             rb_ary_cat(origin_stack, origin, 2);
         }
@@ -1257,28 +1287,25 @@ do_include_modules_at(const VALUE klass, VALUE c, VALUE module, int search_super
             RCLASS_SET_ORIGIN(RARRAY_AREF(origin_stack, (origin_len -= 2)), iclass);
             RICLASS_SET_ORIGIN_SHARED_MTBL(iclass);
             rb_ary_resize(origin_stack, origin_len);
-            add_subclass = FALSE;
         }
 
-	if (add_subclass) {
-	    VALUE m = module;
-            if (BUILTIN_TYPE(m) == T_ICLASS) m = METACLASS_OF(m);
-            rb_module_add_to_subclasses_list(m, iclass);
-	}
+        VALUE m = module;
+        if (BUILTIN_TYPE(m) == T_ICLASS) m = METACLASS_OF(m);
+        rb_module_add_to_subclasses_list(m, iclass);
 
-	if (FL_TEST(klass, RMODULE_IS_REFINEMENT)) {
-	    VALUE refined_class =
-		rb_refinement_module_get_refined_class(klass);
+        if (BUILTIN_TYPE(klass) == T_MODULE && FL_TEST(klass, RMODULE_IS_REFINEMENT)) {
+            VALUE refined_class =
+                rb_refinement_module_get_refined_class(klass);
 
             rb_id_table_foreach(RCLASS_M_TBL(module), add_refined_method_entry_i, (void *)refined_class);
-	    FL_SET(c, RMODULE_INCLUDED_INTO_REFINEMENT);
-	}
+            RUBY_ASSERT(BUILTIN_TYPE(c) == T_MODULE);
+        }
 
         tbl = RCLASS_CONST_TBL(module);
-	if (tbl && rb_id_table_size(tbl))
-	    rb_id_table_foreach(tbl, clear_constant_cache_i, NULL);
+        if (tbl && rb_id_table_size(tbl))
+            rb_id_table_foreach(tbl, clear_constant_cache_i, NULL);
       skip:
-	module = RCLASS_SUPER(module);
+        module = RCLASS_SUPER(module);
     }
 
     return method_changed;
@@ -1300,20 +1327,20 @@ move_refined_method(ID key, VALUE value, void *data)
         struct rb_id_table *tbl = RCLASS_M_TBL(klass);
 
         if (me->def->body.refined.orig_me) {
-	    const rb_method_entry_t *orig_me = me->def->body.refined.orig_me, *new_me;
-	    RB_OBJ_WRITE(me, &me->def->body.refined.orig_me, NULL);
-	    new_me = rb_method_entry_clone(me);
+            const rb_method_entry_t *orig_me = me->def->body.refined.orig_me, *new_me;
+            RB_OBJ_WRITE(me, &me->def->body.refined.orig_me, NULL);
+            new_me = rb_method_entry_clone(me);
             rb_method_table_insert(klass, tbl, key, new_me);
-	    rb_method_entry_copy(me, orig_me);
-	    return ID_TABLE_CONTINUE;
-	}
-	else {
+            rb_method_entry_copy(me, orig_me);
+            return ID_TABLE_CONTINUE;
+        }
+        else {
             rb_method_table_insert(klass, tbl, key, me);
-	    return ID_TABLE_DELETE;
-	}
+            return ID_TABLE_DELETE;
+        }
     }
     else {
-	return ID_TABLE_CONTINUE;
+        return ID_TABLE_CONTINUE;
     }
 }
 
@@ -1337,14 +1364,14 @@ ensure_origin(VALUE klass)
 {
     VALUE origin = RCLASS_ORIGIN(klass);
     if (origin == klass) {
-	origin = class_alloc(T_ICLASS, klass);
-	RCLASS_SET_SUPER(origin, RCLASS_SUPER(klass));
-	RCLASS_SET_SUPER(klass, origin);
-	RCLASS_SET_ORIGIN(klass, origin);
-	RCLASS_M_TBL(origin) = RCLASS_M_TBL(klass);
-	RCLASS_M_TBL_INIT(klass);
+        origin = class_alloc(T_ICLASS, klass);
+        RCLASS_SET_SUPER(origin, RCLASS_SUPER(klass));
+        RCLASS_SET_SUPER(klass, origin);
+        RCLASS_SET_ORIGIN(klass, origin);
+        RCLASS_M_TBL(origin) = RCLASS_M_TBL(klass);
+        RCLASS_M_TBL_INIT(klass);
         rb_id_table_foreach(RCLASS_M_TBL(origin), cache_clear_refined_method, (void *)klass);
-	rb_id_table_foreach(RCLASS_M_TBL(origin), move_refined_method, (void *)klass);
+        rb_id_table_foreach(RCLASS_M_TBL(origin), move_refined_method, (void *)klass);
         return true;
     }
     return false;
@@ -1364,7 +1391,7 @@ rb_prepend_module(VALUE klass, VALUE module)
     changed = do_include_modules_at(klass, klass, module, FALSE, false);
     RUBY_ASSERT(changed >= 0); // already checked for cyclic prepend above
     if (changed) {
-	rb_vm_check_redefinition_by_prepend(klass);
+        rb_vm_check_redefinition_by_prepend(klass);
     }
     if (RB_TYPE_P(klass, T_MODULE)) {
         rb_subclass_entry_t *iclass = RCLASS_SUBCLASSES(klass);
@@ -1381,17 +1408,18 @@ rb_prepend_module(VALUE klass, VALUE module)
             /* During lazy sweeping, iclass->klass could be a dead object that
              * has not yet been swept. */
             if (!rb_objspace_garbage_object_p(iclass->klass)) {
-                if (klass_had_no_origin && klass_origin_m_tbl == RCLASS_M_TBL(iclass->klass)) {
+                const VALUE subclass = iclass->klass;
+                if (klass_had_no_origin && klass_origin_m_tbl == RCLASS_M_TBL(subclass)) {
                     // backfill an origin iclass to handle refinements and future prepends
-                    rb_id_table_foreach(RCLASS_M_TBL(iclass->klass), clear_module_cache_i, (void *)iclass->klass);
-                    RCLASS_M_TBL(iclass->klass) = klass_m_tbl;
-                    VALUE origin = rb_include_class_new(klass_origin, RCLASS_SUPER(iclass->klass));
-                    RCLASS_SET_SUPER(iclass->klass, origin);
-                    RCLASS_SET_INCLUDER(origin, RCLASS_INCLUDER(iclass->klass));
-                    RCLASS_SET_ORIGIN(iclass->klass, origin);
+                    rb_id_table_foreach(RCLASS_M_TBL(subclass), clear_module_cache_i, (void *)subclass);
+                    RCLASS_M_TBL(subclass) = klass_m_tbl;
+                    VALUE origin = rb_include_class_new(klass_origin, RCLASS_SUPER(subclass));
+                    RCLASS_SET_SUPER(subclass, origin);
+                    RCLASS_SET_INCLUDER(origin, RCLASS_INCLUDER(subclass));
+                    RCLASS_SET_ORIGIN(subclass, origin);
                     RICLASS_SET_ORIGIN_SHARED_MTBL(origin);
                 }
-                include_modules_at(iclass->klass, iclass->klass, module, FALSE);
+                include_modules_at(subclass, subclass, module, FALSE);
             }
 
             iclass = iclass->next;
@@ -1430,10 +1458,10 @@ rb_mod_included_modules(VALUE mod)
 
     for (p = RCLASS_SUPER(mod); p; p = RCLASS_SUPER(p)) {
         if (p != origin && RCLASS_ORIGIN(p) == p && BUILTIN_TYPE(p) == T_ICLASS) {
-	    VALUE m = METACLASS_OF(p);
-	    if (RB_TYPE_P(m, T_MODULE))
-		rb_ary_push(ary, m);
-	}
+            VALUE m = METACLASS_OF(p);
+            if (RB_TYPE_P(m, T_MODULE))
+                rb_ary_push(ary, m);
+        }
     }
     return ary;
 }
@@ -1465,8 +1493,8 @@ rb_mod_include_p(VALUE mod, VALUE mod2)
     Check_Type(mod2, T_MODULE);
     for (p = RCLASS_SUPER(mod); p; p = RCLASS_SUPER(p)) {
         if (BUILTIN_TYPE(p) == T_ICLASS && !FL_TEST(p, RICLASS_IS_ORIGIN)) {
-	    if (METACLASS_OF(p) == mod2) return Qtrue;
-	}
+            if (METACLASS_OF(p) == mod2) return Qtrue;
+        }
     }
     return Qfalse;
 }
@@ -1494,19 +1522,19 @@ rb_mod_ancestors(VALUE mod)
 {
     VALUE p, ary = rb_ary_new();
     VALUE refined_class = Qnil;
-    if (FL_TEST(mod, RMODULE_IS_REFINEMENT)) {
+    if (BUILTIN_TYPE(mod) == T_MODULE && FL_TEST(mod, RMODULE_IS_REFINEMENT)) {
         refined_class = rb_refinement_module_get_refined_class(mod);
     }
 
     for (p = mod; p; p = RCLASS_SUPER(p)) {
         if (p == refined_class) break;
         if (p != RCLASS_ORIGIN(p)) continue;
-	if (BUILTIN_TYPE(p) == T_ICLASS) {
-	    rb_ary_push(ary, METACLASS_OF(p));
-	}
+        if (BUILTIN_TYPE(p) == T_ICLASS) {
+            rb_ary_push(ary, METACLASS_OF(p));
+        }
         else {
-	    rb_ary_push(ary, p);
-	}
+            rb_ary_push(ary, p);
+        }
     }
     return ary;
 }
@@ -1580,6 +1608,27 @@ class_descendants(VALUE klass, bool immediate_only)
  *     A.subclasses        #=> [D, B]
  *     B.subclasses        #=> [C]
  *     C.subclasses        #=> []
+ *
+ *  Anonymous subclasses (not associated with a constant) are
+ *  returned, too:
+ *
+ *     c = Class.new(A)
+ *     A.subclasses        # => [#<Class:0x00007f003c77bd78>, D, B]
+ *
+ *  Note that the parent does not hold references to subclasses
+ *  and doesn't prevent them from being garbage collected. This
+ *  means that the subclass might disappear when all references
+ *  to it are dropped:
+ *
+ *     # drop the reference to subclass, it can be garbage-collected now
+ *     c = nil
+ *
+ *     A.subclasses
+ *     # It can be
+ *     #  => [#<Class:0x00007f003c77bd78>, D, B]
+ *     # ...or just
+ *     #  => [D, B]
+ *     # ...depending on whether garbage collector was run
  */
 
 VALUE
@@ -1588,6 +1637,33 @@ rb_class_subclasses(VALUE klass)
     return class_descendants(klass, true);
 }
 
+/*
+ *  call-seq:
+ *     attached_object -> object
+ *
+ *  Returns the object for which the receiver is the singleton class.
+ *
+ *  Raises an TypeError if the class is not a singleton class.
+ *
+ *     class Foo; end
+ *
+ *     Foo.singleton_class.attached_object        #=> Foo
+ *     Foo.attached_object                        #=> TypeError: `Foo' is not a singleton class
+ *     Foo.new.singleton_class.attached_object    #=> #<Foo:0x000000010491a370>
+ *     TrueClass.attached_object                  #=> TypeError: `TrueClass' is not a singleton class
+ *     NilClass.attached_object                   #=> TypeError: `NilClass' is not a singleton class
+ */
+
+VALUE
+rb_class_attached_object(VALUE klass)
+{
+    if (!FL_TEST(klass, FL_SINGLETON)) {
+        rb_raise(rb_eTypeError, "`%"PRIsVALUE"' is not a singleton class", klass);
+    }
+
+    return rb_attr_get(klass, id_attached);
+}
+
 static void
 ins_methods_push(st_data_t name, st_data_t ary)
 {
@@ -1600,10 +1676,10 @@ ins_methods_i(st_data_t name, st_data_t type, st_data_t ary)
     switch ((rb_method_visibility_t)type) {
       case METHOD_VISI_UNDEF:
       case METHOD_VISI_PRIVATE:
-	break;
+        break;
       default: /* everything but private */
-	ins_methods_push(name, ary);
-	break;
+        ins_methods_push(name, ary);
+        break;
     }
     return ST_CONTINUE;
 }
@@ -1612,7 +1688,7 @@ static int
 ins_methods_type_i(st_data_t name, st_data_t type, st_data_t ary, rb_method_visibility_t visi)
 {
     if ((rb_method_visibility_t)type == visi) {
-	ins_methods_push(name, ary);
+        ins_methods_push(name, ary);
     }
     return ST_CONTINUE;
 }
@@ -1635,6 +1711,12 @@ ins_methods_pub_i(st_data_t name, st_data_t type, st_data_t ary)
     return ins_methods_type_i(name, type, ary, METHOD_VISI_PUBLIC);
 }
 
+static int
+ins_methods_undef_i(st_data_t name, st_data_t type, st_data_t ary)
+{
+    return ins_methods_type_i(name, type, ary, METHOD_VISI_UNDEF);
+}
+
 struct method_entry_arg {
     st_table *list;
     int recur;
@@ -1648,20 +1730,20 @@ method_entry_i(ID key, VALUE value, void *data)
     rb_method_visibility_t type;
 
     if (me->def->type == VM_METHOD_TYPE_REFINED) {
-	VALUE owner = me->owner;
-	me = rb_resolve_refined_method(Qnil, me);
-	if (!me) return ID_TABLE_CONTINUE;
-	if (!arg->recur && me->owner != owner) return ID_TABLE_CONTINUE;
+        VALUE owner = me->owner;
+        me = rb_resolve_refined_method(Qnil, me);
+        if (!me) return ID_TABLE_CONTINUE;
+        if (!arg->recur && me->owner != owner) return ID_TABLE_CONTINUE;
     }
     if (!st_is_member(arg->list, key)) {
-	if (UNDEFINED_METHOD_ENTRY_P(me)) {
-	    type = METHOD_VISI_UNDEF; /* none */
-	}
-	else {
-	    type = METHOD_ENTRY_VISI(me);
-	    RUBY_ASSERT(type != METHOD_VISI_UNDEF);
-	}
-	st_add_direct(arg->list, key, (st_data_t)type);
+        if (UNDEFINED_METHOD_ENTRY_P(me)) {
+            type = METHOD_VISI_UNDEF; /* none */
+        }
+        else {
+            type = METHOD_ENTRY_VISI(me);
+            RUBY_ASSERT(type != METHOD_VISI_UNDEF);
+        }
+        st_add_direct(arg->list, key, (st_data_t)type);
     }
     return ID_TABLE_CONTINUE;
 }
@@ -1702,14 +1784,14 @@ class_instance_method_list(int argc, const VALUE *argv, VALUE mod, int obj, int
     }
 
     if (!recur && RCLASS_ORIGIN(mod) != mod) {
-	mod = RCLASS_ORIGIN(mod);
-	prepended = 1;
+        mod = RCLASS_ORIGIN(mod);
+        prepended = 1;
     }
 
     for (; mod; mod = RCLASS_SUPER(mod)) {
         add_instance_method_list(mod, &me_arg);
-	if (BUILTIN_TYPE(mod) == T_ICLASS && !prepended) continue;
-	if (!recur) break;
+        if (BUILTIN_TYPE(mod) == T_ICLASS && !prepended) continue;
+        if (!recur) break;
     }
     ary = rb_ary_new2(me_arg.list->num_entries);
     st_foreach(me_arg.list, func, ary);
@@ -1743,6 +1825,15 @@ class_instance_method_list(int argc, const VALUE *argv, VALUE mod, int obj, int
  *     B.instance_methods(true).include?(:method1) #=> true
  *     C.instance_methods(false)                   #=> [:method3]
  *     C.instance_methods.include?(:method2)       #=> true
+ *
+ *  Note that method visibility changes in the current class, as well as aliases,
+ *  are considered as methods of the current class by this method:
+ *
+ *     class C < B
+ *       alias method4 method2
+ *       protected :method2
+ *     end
+ *     C.instance_methods(false).sort               #=> [:method2, :method3, :method4]
  */
 
 VALUE
@@ -1806,6 +1897,21 @@ rb_class_public_instance_methods(int argc, const VALUE *argv, VALUE mod)
 
 /*
  *  call-seq:
+ *     mod.undefined_instance_methods   -> array
+ *
+ *  Returns a list of the undefined instance methods defined in <i>mod</i>.
+ *  The undefined methods of any ancestors are not included.
+ */
+
+VALUE
+rb_class_undefined_instance_methods(VALUE mod)
+{
+    VALUE include_super = Qfalse;
+    return class_instance_method_list(1, &include_super, mod, 0, ins_methods_undef_i);
+}
+
+/*
+ *  call-seq:
  *     obj.methods(regular=true)    -> array
  *
  *  Returns a list of the names of public and protected methods of
@@ -1839,7 +1945,7 @@ rb_obj_methods(int argc, const VALUE *argv, VALUE obj)
 {
     rb_check_arity(argc, 0, 1);
     if (argc > 0 && !RTEST(argv[0])) {
-	return rb_obj_singleton_methods(argc, argv, obj);
+        return rb_obj_singleton_methods(argc, argv, obj);
     }
     return class_instance_method_list(argc, argv, CLASS_OF(obj), 1, ins_methods_i);
 }
@@ -1939,14 +2045,14 @@ rb_obj_singleton_methods(int argc, const VALUE *argv, VALUE obj)
     me_arg.list = st_init_numtable();
     me_arg.recur = recur;
     if (klass && FL_TEST(klass, FL_SINGLETON)) {
-	if ((mtbl = RCLASS_M_TBL(origin)) != 0) rb_id_table_foreach(mtbl, method_entry_i, &me_arg);
-	klass = RCLASS_SUPER(klass);
+        if ((mtbl = RCLASS_M_TBL(origin)) != 0) rb_id_table_foreach(mtbl, method_entry_i, &me_arg);
+        klass = RCLASS_SUPER(klass);
     }
     if (recur) {
-	while (klass && (FL_TEST(klass, FL_SINGLETON) || RB_TYPE_P(klass, T_ICLASS))) {
-	    if (klass != origin && (mtbl = RCLASS_M_TBL(klass)) != 0) rb_id_table_foreach(mtbl, method_entry_i, &me_arg);
-	    klass = RCLASS_SUPER(klass);
-	}
+        while (klass && (FL_TEST(klass, FL_SINGLETON) || RB_TYPE_P(klass, T_ICLASS))) {
+            if (klass != origin && (mtbl = RCLASS_M_TBL(klass)) != 0) rb_id_table_foreach(mtbl, method_entry_i, &me_arg);
+            klass = RCLASS_SUPER(klass);
+        }
     }
     ary = rb_ary_new2(me_arg.list->num_entries);
     st_foreach(me_arg.list, ins_methods_i, ary);
@@ -2018,7 +2124,7 @@ rb_undef_methods_from(VALUE klass, VALUE super)
 {
     struct rb_id_table *mtbl = RCLASS_M_TBL(super);
     if (mtbl) {
-	rb_id_table_foreach(mtbl, undef_method_i, (void *)klass);
+        rb_id_table_foreach(mtbl, undef_method_i, (void *)klass);
     }
 }
 
@@ -2066,15 +2172,15 @@ singleton_class_of(VALUE obj)
       case T_BIGNUM:
       case T_FLOAT:
       case T_SYMBOL:
-	rb_raise(rb_eTypeError, "can't define singleton");
+        rb_raise(rb_eTypeError, "can't define singleton");
 
       case T_FALSE:
       case T_TRUE:
       case T_NIL:
-	klass = special_singleton_class_of(obj);
-	if (NIL_P(klass))
-	    rb_bug("unknown immediate %p", (void *)obj);
-	return klass;
+        klass = special_singleton_class_of(obj);
+        if (NIL_P(klass))
+            rb_bug("unknown immediate %p", (void *)obj);
+        return klass;
 
       case T_STRING:
         if (FL_TEST_RAW(obj, RSTRING_FSTR)) {
@@ -2085,9 +2191,7 @@ singleton_class_of(VALUE obj)
     klass = METACLASS_OF(obj);
     if (!(FL_TEST(klass, FL_SINGLETON) &&
           rb_attr_get(klass, id_attached) == obj)) {
-	rb_serial_t serial = RCLASS_SERIAL(klass);
-	klass = rb_make_metaclass(obj, klass);
-	RCLASS_SERIAL(klass) = serial;
+        klass = rb_make_metaclass(obj, klass);
     }
 
     RB_FL_SET_RAW(klass, RB_OBJ_FROZEN_RAW(obj));
@@ -2100,11 +2204,11 @@ rb_freeze_singleton_class(VALUE x)
 {
     /* should not propagate to meta-meta-class, and so on */
     if (!(RBASIC(x)->flags & FL_SINGLETON)) {
-	VALUE klass = RBASIC_CLASS(x);
-	if (klass && (klass = RCLASS_ORIGIN(klass)) != 0 &&
-	    FL_TEST(klass, (FL_SINGLETON|FL_FREEZE)) == FL_SINGLETON) {
-	    OBJ_FREEZE_RAW(klass);
-	}
+        VALUE klass = RBASIC_CLASS(x);
+        if (klass && // no class when hidden from ObjectSpace
+            FL_TEST(klass, (FL_SINGLETON|FL_FREEZE)) == FL_SINGLETON) {
+            OBJ_FREEZE_RAW(klass);
+        }
     }
 }
 
@@ -2121,7 +2225,7 @@ rb_singleton_class_get(VALUE obj)
     VALUE klass;
 
     if (SPECIAL_CONST_P(obj)) {
-	return rb_special_singleton_class(obj);
+        return rb_special_singleton_class(obj);
     }
     klass = METACLASS_OF(obj);
     if (!FL_TEST(klass, FL_SINGLETON)) return Qnil;
@@ -2196,13 +2300,13 @@ rb_keyword_error_new(const char *error, VALUE keys)
     VALUE error_message = rb_sprintf("%s keyword%.*s", error, len > 1, "s");
 
     if (len > 0) {
-	rb_str_cat_cstr(error_message, ": ");
-	while (1) {
+        rb_str_cat_cstr(error_message, ": ");
+        while (1) {
             const VALUE k = RARRAY_AREF(keys, i);
-	    rb_str_append(error_message, rb_inspect(k));
-	    if (++i >= len) break;
-	    rb_str_cat_cstr(error_message, ", ");
-	}
+            rb_str_append(error_message, rb_inspect(k));
+            if (++i >= len) break;
+            rb_str_cat_cstr(error_message, ", ");
+        }
     }
 
     return rb_exc_new_str(rb_eArgError, error_message);
@@ -2221,7 +2325,7 @@ unknown_keyword_error(VALUE hash, const ID *table, int keywords)
 {
     int i;
     for (i = 0; i < keywords; i++) {
-	st_data_t key = ID2SYM(table[i]);
+        st_data_t key = ID2SYM(table[i]);
         rb_hash_stlike_delete(hash, &key, NULL);
     }
     rb_keyword_error("unknown", rb_hash_keys(hash));
@@ -2245,8 +2349,8 @@ rb_extract_keywords(VALUE *orighash)
     VALUE hash = *orighash;
 
     if (RHASH_EMPTY_P(hash)) {
-	*orighash = 0;
-	return hash;
+        *orighash = 0;
+        return hash;
     }
     rb_hash_foreach(hash, separate_symbol, (st_data_t)&parthash);
     *orighash = parthash[1];
@@ -2272,36 +2376,36 @@ rb_get_kwargs(VALUE keyword_hash, const ID *table, int required, int optional, V
     if (NIL_P(keyword_hash)) keyword_hash = 0;
 
     if (optional < 0) {
-	rest = 1;
-	optional = -1-optional;
+        rest = 1;
+        optional = -1-optional;
     }
     if (required) {
-	for (; i < required; i++) {
-	    VALUE keyword = ID2SYM(table[i]);
-	    if (keyword_hash) {
+        for (; i < required; i++) {
+            VALUE keyword = ID2SYM(table[i]);
+            if (keyword_hash) {
                 if (extract_kwarg(keyword, values[i])) {
-		    continue;
-		}
-	    }
-	    if (NIL_P(missing)) missing = rb_ary_tmp_new(1);
-	    rb_ary_push(missing, keyword);
-	}
-	if (!NIL_P(missing)) {
-	    rb_keyword_error("missing", missing);
-	}
+                    continue;
+                }
+            }
+            if (NIL_P(missing)) missing = rb_ary_hidden_new(1);
+            rb_ary_push(missing, keyword);
+        }
+        if (!NIL_P(missing)) {
+            rb_keyword_error("missing", missing);
+        }
     }
     j = i;
     if (optional && keyword_hash) {
-	for (i = 0; i < optional; i++) {
+        for (i = 0; i < optional; i++) {
             if (extract_kwarg(ID2SYM(table[required+i]), values[required+i])) {
-		j++;
-	    }
-	}
+                j++;
+            }
+        }
     }
     if (!rest && keyword_hash) {
-	if (RHASH_SIZE(keyword_hash) > (unsigned int)(values ? 0 : j)) {
-	    unknown_keyword_error(keyword_hash, table, required+optional);
-	}
+        if (RHASH_SIZE(keyword_hash) > (unsigned int)(values ? 0 : j)) {
+            unknown_keyword_error(keyword_hash, table, required+optional);
+        }
     }
     if (values && !keyword_hash) {
         for (i = 0; i < required + optional; i++) {
@@ -2332,30 +2436,30 @@ rb_scan_args_parse(int kw_flag, const char *fmt, struct rb_scan_args_t *arg)
 
     if (ISDIGIT(*p)) {
         arg->n_lead = *p - '0';
-	p++;
-	if (ISDIGIT(*p)) {
+        p++;
+        if (ISDIGIT(*p)) {
             arg->n_opt = *p - '0';
-	    p++;
-	}
+            p++;
+        }
     }
     if (*p == '*') {
         arg->f_var = 1;
-	p++;
+        p++;
     }
     if (ISDIGIT(*p)) {
         arg->n_trail = *p - '0';
-	p++;
+        p++;
     }
     if (*p == ':') {
         arg->f_hash = 1;
-	p++;
+        p++;
     }
     if (*p == '&') {
         arg->f_block = 1;
-	p++;
+        p++;
     }
     if (*p != '\0') {
-	rb_fatal("bad scan arg format: %s", fmt);
+        rb_fatal("bad scan arg format: %s", fmt);
     }
 }
 
@@ -2391,37 +2495,37 @@ rb_scan_args_assign(const struct rb_scan_args_t *arg, int argc, const VALUE *con
     for (i = 0; i < n_lead; i++) {
         var = rb_scan_args_next_param();
         if (var) *var = argv[argi];
-	argi++;
+        argi++;
     }
     /* capture optional arguments */
     for (i = 0; i < n_opt; i++) {
         var = rb_scan_args_next_param();
         if (argi < argc - n_trail) {
             if (var) *var = argv[argi];
-	    argi++;
-	}
-	else {
-	    if (var) *var = Qnil;
-	}
+            argi++;
+        }
+        else {
+            if (var) *var = Qnil;
+        }
     }
     /* capture variable length arguments */
     if (f_var) {
         int n_var = argc - argi - n_trail;
 
         var = rb_scan_args_next_param();
-	if (0 < n_var) {
+        if (0 < n_var) {
             if (var) *var = rb_ary_new_from_values(n_var, &argv[argi]);
-	    argi += n_var;
-	}
-	else {
-	    if (var) *var = rb_ary_new();
-	}
+            argi += n_var;
+        }
+        else {
+            if (var) *var = rb_ary_new();
+        }
     }
     /* capture trailing mandatory arguments */
     for (i = 0; i < n_trail; i++) {
         var = rb_scan_args_next_param();
         if (var) *var = argv[argi];
-	argi++;
+        argi++;
     }
     /* capture an option hash - phase 2: assignment */
     if (f_hash) {
@@ -2431,12 +2535,12 @@ rb_scan_args_assign(const struct rb_scan_args_t *arg, int argc, const VALUE *con
     /* capture iterator block */
     if (f_block) {
         var = rb_scan_args_next_param();
-	if (rb_block_given_p()) {
-	    *var = rb_block_proc();
-	}
-	else {
-	    *var = Qnil;
-	}
+        if (rb_block_given_p()) {
+            *var = rb_block_proc();
+        }
+        else {
+            *var = Qnil;
+        }
     }
 
     if (argi == argc) {
diff --git a/common.mk b/common.mk
index b4adb2729c..126053c9c8 100644
--- a/common.mk
+++ b/common.mk
@@ -18,8 +18,10 @@ mflags = $(MFLAGS)
 gnumake_recursive =
 enable_shared = $(ENABLE_SHARED:no=)
 
-UNICODE_VERSION = 14.0.0
-UNICODE_EMOJI_VERSION = 14.0
+UNICODE_VERSION = 15.0.0
+UNICODE_EMOJI_VERSION_0 = $(UNICODE_VERSION)///
+UNICODE_EMOJI_VERSION_1 = $(UNICODE_EMOJI_VERSION_0:.0///=)
+UNICODE_EMOJI_VERSION = $(UNICODE_EMOJI_VERSION_1:///=)
 UNICODE_BETA = NO
 
 ### set the following environment variable or uncomment the line if
@@ -41,14 +43,14 @@ RUN_OPTS      = --disable-gems
 
 # GITPULLOPTIONS = --no-tags
 
-INCFLAGS = -I. -I$(arch_hdrdir) -I$(hdrdir) -I$(srcdir) -I$(UNICODE_HDR_DIR)
+INCFLAGS = -I. -I$(arch_hdrdir) -I$(hdrdir) -I$(srcdir) -I$(UNICODE_HDR_DIR) $(incflags)
 
 GEM_HOME =
 GEM_PATH =
 GEM_VENDOR =
 
 BENCHMARK_DRIVER_GIT_URL = https://github.com/benchmark-driver/benchmark-driver
-BENCHMARK_DRIVER_GIT_REF = v0.15.17
+BENCHMARK_DRIVER_GIT_REF = v0.16.0
 SIMPLECOV_GIT_URL = https://github.com/colszowka/simplecov.git
 SIMPLECOV_GIT_REF = v0.17.0
 SIMPLECOV_HTML_GIT_URL = https://github.com/colszowka/simplecov-html.git
@@ -82,7 +84,7 @@ EXTSOLIBS     =
 MINIOBJS      = $(ARCHMINIOBJS) miniinit.$(OBJEXT) dmyext.$(OBJEXT)
 ENC_MK        = enc.mk
 MAKE_ENC      = -f $(ENC_MK) V="$(V)" UNICODE_HDR_DIR="$(UNICODE_HDR_DIR)" \
-		RUBY="$(MINIRUBY)" MINIRUBY="$(MINIRUBY)" $(mflags)
+		RUBY="$(BOOTSTRAPRUBY)" MINIRUBY="$(BOOTSTRAPRUBY)" $(mflags)
 
 COMMONOBJS    = array.$(OBJEXT) \
 		ast.$(OBJEXT) \
@@ -113,7 +115,7 @@ COMMONOBJS    = array.$(OBJEXT) \
 		math.$(OBJEXT) \
 		memory_view.$(OBJEXT) \
 		mjit.$(OBJEXT) \
-		mjit_compile.$(OBJEXT) \
+		mjit_c.$(OBJEXT) \
 		node.$(OBJEXT) \
 		numeric.$(OBJEXT) \
 		object.$(OBJEXT) \
@@ -134,6 +136,7 @@ COMMONOBJS    = array.$(OBJEXT) \
 		regsyntax.$(OBJEXT) \
 		ruby.$(OBJEXT) \
 		scheduler.$(OBJEXT) \
+		shape.$(OBJEXT) \
 		signal.$(OBJEXT) \
 		sprintf.$(OBJEXT) \
 		st.$(OBJEXT) \
@@ -153,7 +156,7 @@ COMMONOBJS    = array.$(OBJEXT) \
 		vm_dump.$(OBJEXT) \
 		vm_sync.$(OBJEXT) \
 		vm_trace.$(OBJEXT) \
-		yjit.$(OBJEXT) \
+		$(YJIT_OBJ) \
 		$(COROUTINE_OBJ) \
 		$(DTRACE_OBJ) \
 		$(BUILTIN_ENCOBJS) \
@@ -195,6 +198,7 @@ INSTRUBY_ARGS =	$(SCRIPT_ARGS) \
 INSTALL_PROG_MODE = 0755
 INSTALL_DATA_MODE = 0644
 
+BOOTSTRAPRUBY_COMMAND = $(BOOTSTRAPRUBY) $(BOOTSTRAPRUBY_OPT)
 TESTSDIR      = $(srcdir)/test
 TOOL_TESTSDIR = $(tooldir)/test
 TEST_EXCLUDES = --excludes-dir=$(TESTSDIR)/excludes --name=!/memory_leak/
@@ -216,12 +220,27 @@ MAKE_LINK = $(MINIRUBY) -rfileutils -e "include FileUtils::Verbose" \
 	  -e "noraise {ln(src, dest)} or" \
 	  -e "cp(src, dest)"
 
+# For release builds
+YJIT_RUSTC_ARGS = --crate-name=yjit \
+	--crate-type=staticlib \
+	--edition=2021 \
+	-g \
+	-C opt-level=3 \
+	-C overflow-checks=on \
+	'--out-dir=$(CARGO_TARGET_DIR)/release/' \
+	$(top_srcdir)/yjit/src/lib.rs
 
 all: $(SHOWFLAGS) main docs
 
 main: $(SHOWFLAGS) exts $(ENCSTATIC:static=lib)encs
 	@$(NULLCMD)
 
+main: $(srcdir)/lib/ruby_vm/mjit/instruction.rb
+srcs: $(srcdir)/lib/ruby_vm/mjit/instruction.rb
+$(srcdir)/lib/ruby_vm/mjit/instruction.rb: $(tooldir)/insns2vm.rb $(tooldir)/ruby_vm/views/lib/ruby_vm/mjit/instruction.rb.erb $(srcdir)/insns.def
+	$(ECHO) generating $@
+	$(Q) $(BASERUBY) -Ku $(tooldir)/insns2vm.rb --basedir="$(srcdir)" $(INSNS2VMOPT) $@
+
 mjit-headers: $(MJIT_SUPPORT)-mjit-headers
 no-mjit-headers: PHONY
 yes-mjit-headers: mjit_config.h PHONY
@@ -229,6 +248,9 @@ yes-mjit-headers: mjit_config.h PHONY
 mjit.$(OBJEXT): mjit_config.h
 mjit_config.h: Makefile
 
+.PHONY: mjit-bindgen
+mjit-bindgen:
+	$(Q) $(BASERUBY) -rrubygems -C $(srcdir)/tool/mjit bindgen.rb $(CURDIR)
 
 # These rules using MJIT_HEADER_SUFFIX must be in common.mk, not
 # Makefile.in, in order to override the macro in defs/universal.mk.
@@ -270,6 +292,8 @@ showflags:
 	"	LC_ALL = $(LC_ALL)" \
 	"	LC_CTYPE = $(LC_CTYPE)" \
 	"	MFLAGS = $(MFLAGS)" \
+	"	RUSTC = $(RUSTC)" \
+	"	YJIT_RUSTC_ARGS = $(YJIT_RUSTC_ARGS)" \
 	$(MESSAGE_END)
 	-@$(CC_VERSION)
 
@@ -610,12 +634,13 @@ clear-installed-list: PHONY
 
 clean: clean-ext clean-enc clean-golf clean-docs clean-extout clean-local clean-platform clean-spec
 clean-local:: clean-runnable
-	$(Q)$(RM) $(OBJS) $(MINIOBJS) $(MAINOBJ) $(LIBRUBY_A) $(LIBRUBY_SO) $(LIBRUBY) $(LIBRUBY_ALIASES)
+	$(Q)$(RM) $(OBJS) $(MINIOBJS) $(INITOBJS) $(MAINOBJ) $(LIBRUBY_A) $(LIBRUBY_SO) $(LIBRUBY) $(LIBRUBY_ALIASES)
 	$(Q)$(RM) $(PROGRAM) $(WPROGRAM) miniruby$(EXEEXT) dmyext.$(OBJEXT) dmyenc.$(OBJEXT) $(ARCHFILE) .*.time
 	$(Q)$(RM) y.tab.c y.output encdb.h transdb.h config.log rbconfig.rb $(ruby_pc) $(COROUTINE_H:/Context.h=/.time)
 	$(Q)$(RM) probes.h probes.$(OBJEXT) probes.stamp ruby-glommed.$(OBJEXT) ruby.imp ChangeLog $(STATIC_RUBY)$(EXEEXT)
 	$(Q)$(RM) GNUmakefile.old Makefile.old $(arch)-fake.rb bisect.sh $(ENC_TRANS_D) builtin_binary.inc
-	-$(Q) $(RMDIR) enc/jis enc/trans enc $(COROUTINE_H:/Context.h=) coroutine 2> $(NULL) || $(NULLCMD)
+	-$(Q)$(RMALL) yjit/target
+	-$(Q) $(RMDIR) enc/jis enc/trans enc $(COROUTINE_H:/Context.h=) coroutine yjit 2> $(NULL) || $(NULLCMD)
 
 bin/clean-runnable:: PHONY
 	$(Q)$(CHDIR) bin 2>$(NULL) && $(RM) $(PROGRAM) $(WPROGRAM) $(GORUBY)$(EXEEXT) bin/*.$(DLEXT) 2>$(NULL) || $(NULLCMD)
@@ -687,18 +712,18 @@ realclean-platform: distclean-platform
 realclean-spec: distclean-spec
 realclean-rubyspec: realclean-spec
 
-clean-ext:: ext/clean gems/clean timestamp/clean
-distclean-ext:: ext/distclean gems/distclean timestamp/distclean
-realclean-ext:: ext/realclean gems/realclean timestamp/realclean
+clean-ext:: ext/clean .bundle/clean timestamp/clean
+distclean-ext:: ext/distclean .bundle/distclean timestamp/distclean
+realclean-ext:: ext/realclean .bundle/realclean timestamp/realclean
 
 ext/clean.mk ext/distclean.mk ext/realclean.mk::
 ext/clean:: ext/clean.mk
 ext/distclean:: ext/distclean.mk
 ext/realclean:: ext/realclean.mk
 
-timestamp/clean:: ext/clean gems/clean
-timestamp/distclean:: ext/distclean gems/distclean
-timestamp/realclean:: ext/realclean gems/realclean
+timestamp/clean:: ext/clean .bundle/clean
+timestamp/distclean:: ext/distclean .bundle/distclean
+timestamp/realclean:: ext/realclean .bundle/realclean
 
 timestamp/clean timestamp/distclean timestamp/realclean::
 	$(Q)$(RM) $(TIMESTAMPDIR)/.*.time $(TIMESTAMPDIR)/$(arch)/.time
@@ -741,7 +766,7 @@ clean-spec: PHONY
 	-$(Q) $(RMDIRS) $(RUBYSPEC_CAPIEXT) 2> $(NULL) || $(NULLCMD)
 	-$(Q) $(RMALL) rubyspec_temp
 
-check: main test test-tool test-all test-spec
+check: main $(DOT_WAIT) test $(DOT_WAIT) test-tool $(DOT_WAIT) test-all
 	$(ECHO) check succeeded
 	-$(Q) : : "run only on sh"; \
 	if [ x"$(GIT)" != x ] && $(CHDIR) "$(srcdir)" && \
@@ -755,26 +780,34 @@ fake: $(CROSS_COMPILING)-fake
 yes-fake: $(arch)-fake.rb $(RBCONFIG) PHONY
 no-fake -fake: PHONY
 
-# really doesn't depend on .o, just ensure newer than headers which
-# version.o depends on.
-$(arch)-fake.rb: $(srcdir)/template/fake.rb.in $(tooldir)/generic_erb.rb version.$(OBJEXT) miniruby$(EXEEXT)
+$(HAVE_BASERUBY:no=)$(arch)-fake.rb: miniruby$(EXEEXT)
+
+# actually depending on other headers more.
+$(arch:noarch=ignore)-fake.rb: $(top_srcdir)/revision.h $(top_srcdir)/version.h $(srcdir)/version.c
+$(arch:noarch=ignore)-fake.rb: {$(VPATH)}id.h {$(VPATH)}vm_opts.h
+
+$(arch:noarch=ignore)-fake.rb: $(srcdir)/template/fake.rb.in $(tooldir)/generic_erb.rb
 	$(ECHO) generating $@
 	$(Q) $(CPP) -DRUBY_EXPORT $(INCFLAGS) $(CPPFLAGS) "$(srcdir)/version.c" | \
 	$(BOOTSTRAPRUBY) "$(tooldir)/generic_erb.rb" -o $@ "$(srcdir)/template/fake.rb.in" \
-		i=- srcdir="$(srcdir)" BASERUBY="$(BASERUBY)"
+	    i=- srcdir="$(srcdir)" BASERUBY="$(BASERUBY)" \
+	    LIBPATHENV="$(LIBPATHENV)" PRELOADENV="$(PRELOADENV)" LIBRUBY_SO="$(LIBRUBY_SO)"
+
+noarch-fake.rb: # prerequisite of yes-fake
+	$(Q) exit > $@
 
 btest: $(TEST_RUNNABLE)-btest
 no-btest: PHONY
 yes-btest: yes-fake miniruby$(EXEEXT) PHONY
 	$(ACTIONS_GROUP)
-	$(Q)$(exec) $(BOOTSTRAPRUBY) "$(srcdir)/bootstraptest/runner.rb" --ruby="$(BTESTRUBY) $(RUN_OPTS)" $(OPTS) $(TESTOPTS) $(BTESTS)
+	$(Q)$(gnumake_recursive)$(exec) $(BOOTSTRAPRUBY) "$(srcdir)/bootstraptest/runner.rb" --ruby="$(BTESTRUBY) $(RUN_OPTS)" $(OPTS) $(TESTOPTS) $(BTESTS)
 	$(ACTIONS_ENDGROUP)
 
 btest-ruby: $(TEST_RUNNABLE)-btest-ruby
 no-btest-ruby: PHONY
 yes-btest-ruby: prog PHONY
 	$(ACTIONS_GROUP)
-	$(Q)$(exec) $(RUNRUBY) "$(srcdir)/bootstraptest/runner.rb" --ruby="$(PROGRAM) -I$(srcdir)/lib $(RUN_OPTS)" -q $(OPTS) $(TESTOPTS) $(BTESTS)
+	$(Q)$(gnumake_recursive)$(exec) $(RUNRUBY) "$(srcdir)/bootstraptest/runner.rb" --ruby="$(PROGRAM) -I$(srcdir)/lib $(RUN_OPTS)" $(OPTS) $(TESTOPTS) $(BTESTS)
 	$(ACTIONS_ENDGROUP)
 
 rtest: yes-fake miniruby$(EXEEXT) PHONY
@@ -812,7 +845,7 @@ yes-test-tool: prog PHONY
 no-test-tool: PHONY
 
 test-sample: test-basic # backward compatibility for mswin-build
-test-short: btest-ruby test-knownbug test-basic
+test-short: btest-ruby $(DOT_WAIT) test-knownbug $(DOT_WAIT) test-basic
 test: test-short
 
 # $ make test-all TESTOPTS="--help" displays more detail
@@ -839,7 +872,10 @@ extconf: $(PREP)
 	$(Q) $(MAKEDIRS) "$(EXTCONFDIR)"
 	$(RUNRUBY) -C "$(EXTCONFDIR)" $(EXTCONF) $(EXTCONFARGS)
 
-$(RBCONFIG): $(tooldir)/mkconfig.rb config.status $(srcdir)/version.h
+rbconfig.rb: $(RBCONFIG)
+
+$(HAVE_BASERUBY:no=)$(RBCONFIG)$(HAVE_BASERUBY:no=): $(PREP)
+$(RBCONFIG): $(tooldir)/mkconfig.rb config.status $(srcdir)/version.h $(srcdir)/common.mk
 	$(Q)$(BOOTSTRAPRUBY) -n \
 	-e 'BEGIN{version=ARGV.shift;mis=ARGV.dup}' \
 	-e 'END{abort "UNICODE version mismatch: #{mis}" unless mis.empty?}' \
@@ -857,7 +893,7 @@ $(RBCONFIG): $(tooldir)/mkconfig.rb config.status $(srcdir)/version.h
 test-rubyspec: test-spec
 yes-test-rubyspec: yes-test-spec
 
-test-spec-precheck: programs
+test-spec-precheck: programs yes-fake
 
 test-spec: $(TEST_RUNNABLE)-test-spec
 yes-test-spec: test-spec-precheck
@@ -867,6 +903,8 @@ yes-test-spec: test-spec-precheck
 	$(ACTIONS_ENDGROUP)
 no-test-spec:
 
+check: $(DOT_WAIT) test-spec
+
 RUNNABLE = $(LIBRUBY_RELATIVE:no=un)-runnable
 runnable: $(RUNNABLE) prog $(tooldir)/mkrunnable.rb PHONY
 	$(Q) $(MINIRUBY) $(tooldir)/mkrunnable.rb -v $(EXTOUT)
@@ -885,9 +923,10 @@ libtrans trans: {$(VPATH)}transdb.h
 ENC_HEADERS = $(srcdir)/enc/jis/props.h
 # Use MINIRUBY which loads fake.rb for cross compiling
 $(ENC_MK): $(srcdir)/enc/make_encmake.rb $(srcdir)/enc/Makefile.in $(srcdir)/enc/depend \
-	   $(srcdir)/enc/encinit.c.erb $(ENC_HEADERS) $(srcdir)/lib/mkmf.rb $(RBCONFIG) fake
+	   $(srcdir)/enc/encinit.c.erb $(ENC_HEADERS) $(srcdir)/lib/mkmf.rb $(RBCONFIG) $(HAVE_BASERUBY)-fake
 	$(ECHO) generating $@
-	$(Q) $(MINIRUBY) $(srcdir)/enc/make_encmake.rb --builtin-encs="$(BUILTIN_ENCOBJS)" --builtin-transes="$(BUILTIN_TRANSOBJS)" --module$(ENCSTATIC) $(ENCS) $@
+	$(Q) $(BOOTSTRAPRUBY_COMMAND) $(srcdir)/enc/make_encmake.rb \
+	  --builtin-encs="$(BUILTIN_ENCOBJS)" --builtin-transes="$(BUILTIN_TRANSOBJS)" --module$(ENCSTATIC) $(ENCS) $@
 
 .PRECIOUS: $(MKFILES)
 
@@ -909,9 +948,7 @@ PHONY:
 
 {$(srcdir)}.y.c:
 	$(ECHO) generating $@
-	$(Q)$(BASERUBY) $(tooldir)/id2token.rb --path-separator=.$(PATH_SEPARATOR)./ --vpath=$(VPATH) id.h $(SRC_FILE) > parse.tmp.y
-	$(Q)$(BASERUBY) $(tooldir)/pure_parser.rb parse.tmp.y $(YACC)
-	$(Q)$(RM) parse.tmp.y.bak
+	$(Q)$(BASERUBY) $(tooldir)/id2token.rb $(SRC_FILE) > parse.tmp.y
 	$(Q)$(YACC) -d $(YFLAGS) -o y.tab.c parse.tmp.y
 	$(Q)$(RM) parse.tmp.y
 	$(Q)sed -f $(tooldir)/ytab.sed -e "/^#/s|parse\.tmp\.[iy]|$(SRC_FILE)|" -e "/^#/s!y\.tab\.c!$@!" y.tab.c > $@.new
@@ -923,11 +960,11 @@ $(PLATFORM_D):
 	$(Q) $(MAKEDIRS) $(PLATFORM_DIR) $(@D)
 	@$(NULLCMD) > $@
 
-exe/$(PROGRAM): ruby-runner.c ruby-runner.h exe/.time miniruby$(EXEEXT) {$(VPATH)}config.h
+exe/$(PROGRAM): ruby-runner.c ruby-runner.h exe/.time $(PREP) {$(VPATH)}config.h
 	$(Q) $(CC) $(CFLAGS) $(INCFLAGS) $(CPPFLAGS) -DRUBY_INSTALL_NAME=$(@F) $(COUTFLAG)ruby-runner.$(OBJEXT) -c $(CSRCFLAG)$(srcdir)/ruby-runner.c
 	$(Q) $(PURIFY) $(CC) $(CFLAGS) $(LDFLAGS) $(OUTFLAG)$@ ruby-runner.$(OBJEXT) $(LIBS)
 	$(Q) $(POSTLINK)
-	$(Q) ./miniruby$(EXEEXT) \
+	$(Q) $(BOOTSTRAPRUBY) \
 	    -e 'prog, dest, inst = ARGV; dest += "/ruby"' \
 	    -e 'exit unless prog==inst' \
 	    -e 'unless prog=="ruby"' \
@@ -1041,11 +1078,7 @@ $(srcs_vpath)insns_info.inc: $(tooldir)/ruby_vm/views/insns_info.inc.erb $(inc_c
 $(srcs_vpath)vmtc.inc: $(tooldir)/ruby_vm/views/vmtc.inc.erb $(inc_common_headers)
 $(srcs_vpath)vm.inc: $(tooldir)/ruby_vm/views/vm.inc.erb $(inc_common_headers) \
   $(tooldir)/ruby_vm/views/_insn_entry.erb $(tooldir)/ruby_vm/views/_trace_instruction.erb
-$(srcs_vpath)mjit_compile.inc: $(tooldir)/ruby_vm/views/mjit_compile.inc.erb $(inc_common_headers) \
-  $(tooldir)/ruby_vm/views/_mjit_compile_insn.erb $(tooldir)/ruby_vm/views/_mjit_compile_send.erb \
-  $(tooldir)/ruby_vm/views/_mjit_compile_ivar.erb \
-  $(tooldir)/ruby_vm/views/_mjit_compile_insn_body.erb $(tooldir)/ruby_vm/views/_mjit_compile_pc_and_sp.erb \
-  $(tooldir)/ruby_vm/views/_mjit_compile_invokebuiltin.erb $(tooldir)/ruby_vm/views/_mjit_compile_getinlinecache.erb
+$(srcs_vpath)mjit_sp_inc.inc: $(tooldir)/ruby_vm/views/mjit_sp_inc.inc.erb
 
 BUILTIN_RB_SRCS = \
 		$(srcdir)/ast.rb \
@@ -1054,13 +1087,17 @@ BUILTIN_RB_SRCS = \
 		$(srcdir)/numeric.rb \
 		$(srcdir)/io.rb \
 		$(srcdir)/marshal.rb \
+		$(srcdir)/mjit.rb \
+		$(srcdir)/mjit_c.rb \
 		$(srcdir)/pack.rb \
 		$(srcdir)/trace_point.rb \
 		$(srcdir)/warning.rb \
 		$(srcdir)/array.rb \
 		$(srcdir)/kernel.rb \
 		$(srcdir)/ractor.rb \
+		$(srcdir)/symbol.rb \
 		$(srcdir)/timev.rb \
+		$(srcdir)/thread_sync.rb \
 		$(srcdir)/nilclass.rb \
 		$(srcdir)/prelude.rb \
 		$(srcdir)/gem_prelude.rb \
@@ -1070,7 +1107,7 @@ BUILTIN_RB_INCS = $(BUILTIN_RB_SRCS:.rb=.rbinc)
 
 common-srcs: $(srcs_vpath)parse.c $(srcs_vpath)lex.c $(srcs_vpath)enc/trans/newline.c $(srcs_vpath)id.c \
 	     $(BUILTIN_RB_INCS) \
-	     srcs-lib srcs-ext incs
+	     srcs-lib srcs-ext incs preludes
 
 missing-srcs: $(srcdir)/missing/des_tables.c
 
@@ -1126,13 +1163,13 @@ node_name.inc: $(tooldir)/node_name.rb $(srcdir)/node.h
 	$(ECHO) generating $@
 	$(Q) $(BASERUBY) -n $(tooldir)/node_name.rb < $(srcdir)/node.h > $@
 
-encdb.h: $(PREP) $(tooldir)/generic_erb.rb $(srcdir)/template/encdb.h.tmpl
+encdb.h: $(RBCONFIG) $(tooldir)/generic_erb.rb $(srcdir)/template/encdb.h.tmpl
 	$(ECHO) generating $@
-	$(Q) $(MINIRUBY) $(tooldir)/generic_erb.rb -c -o $@ $(srcdir)/template/encdb.h.tmpl $(srcdir)/enc enc
+	$(Q) $(BOOTSTRAPRUBY) $(tooldir)/generic_erb.rb -c -o $@ $(srcdir)/template/encdb.h.tmpl $(srcdir)/enc enc
 
-transdb.h: $(PREP) srcs-enc $(tooldir)/generic_erb.rb $(srcdir)/template/transdb.h.tmpl
+transdb.h: $(RBCONFIG) srcs-enc $(tooldir)/generic_erb.rb $(srcdir)/template/transdb.h.tmpl
 	$(ECHO) generating $@
-	$(Q) $(MINIRUBY) $(tooldir)/generic_erb.rb -c -o $@ $(srcdir)/template/transdb.h.tmpl $(srcdir)/enc/trans enc/trans
+	$(Q) $(BOOTSTRAPRUBY) $(tooldir)/generic_erb.rb -c -o $@ $(srcdir)/template/transdb.h.tmpl $(srcdir)/enc/trans enc/trans
 
 enc/encinit.c: $(ENC_MK) $(srcdir)/enc/encinit.c.erb
 
@@ -1182,25 +1219,19 @@ builtin_binary.inc: $(PREP) $(BUILTIN_RB_SRCS) $(srcdir)/template/builtin_binary
 
 $(BUILTIN_RB_INCS): $(top_srcdir)/tool/mk_builtin_loader.rb
 
-$(srcdir)/revision.h:
-$(srcdir)/revision.h$(gnumake:yes=-nongnumake):
-	$(Q)$(RM) $(@F)
-	$(Q)$(NULLCMD) > $@ || $(NULLCMD) > $(@F)
+$(srcdir)/revision.h$(no_baseruby:no=~disabled~): $(REVISION_H)
 
-revision.tmp::
-	$(Q) $(NULLCMD) > $@
-revision.$(HAVE_BASERUBY:yes=tmp):: $(srcdir)/version.h $(tooldir)/file2lastrev.rb $(REVISION_FORCE)
-	$(Q) $(BASERUBY) $(tooldir)/file2lastrev.rb -q --revision.h --srcdir="$(srcdir)" > $@
+$(REVISION_H)$(no_baseruby:no=~disabled~):
+	$(Q) $(BASERUBY) $(tooldir)/file2lastrev.rb -q --revision.h --srcdir="$(srcdir)" --output=revision.h --timestamp=$@
+$(REVISION_H)$(yes_baseruby:yes=~disabled~):
+	$(Q) exit > $@
 
-$(REVISION_H): revision.tmp
-	$(Q)$(IFCHANGE) "--timestamp=$@" "$(srcdir)/revision.h" revision.tmp
-
-$(srcdir)/ext/ripper/ripper.c: $(srcdir)/ext/ripper/tools/preproc.rb $(srcdir)/parse.y id.h $(srcdir)/ext/ripper/depend
+$(srcdir)/ext/ripper/ripper.c: $(srcdir)/ext/ripper/tools/preproc.rb $(srcdir)/parse.y $(srcdir)/defs/id.def $(srcdir)/ext/ripper/depend
 	$(ECHO) generating $@
 	$(Q) $(CHDIR) $(@D) && \
-	sed -e 's/{\$$([^(){}]*)[^{}]*}//g' -e /AUTOGENERATED/q depend | \
+	$(CAT_DEPEND) depend | \
 	$(exec) $(MAKE) -f - $(mflags) \
-		Q=$(Q) ECHO=$(ECHO) RM="$(RM1)" BISON=$(YACC) top_srcdir=../.. srcdir=. VPATH=../.. \
+		Q=$(Q) ECHO=$(ECHO) RM="$(RM1)" BISON="$(YACC)" top_srcdir=../.. srcdir=. VPATH=../.. \
 		RUBY="$(BASERUBY)" PATH_SEPARATOR="$(PATH_SEPARATOR)" LANG=C
 
 $(srcdir)/ext/json/parser/parser.c: $(srcdir)/ext/json/parser/parser.rl $(srcdir)/ext/json/parser/prereq.mk
@@ -1217,7 +1248,7 @@ $(srcdir)/ext/rbconfig/sizeof/sizes.c: $(srcdir)/ext/rbconfig/sizeof/depend \
 		$(tooldir)/generic_erb.rb $(srcdir)/template/sizes.c.tmpl $(srcdir)/configure.ac
 	$(ECHO) generating $@
 	$(Q) $(CHDIR) $(@D) && \
-	sed '/AUTOGENERATED/q' depend | \
+	$(CAT_DEPEND) depend | \
 	$(exec) $(MAKE) -f - $(mflags) \
 		Q=$(Q) ECHO=$(ECHO) top_srcdir=../../.. srcdir=. VPATH=../../.. RUBY="$(BASERUBY)" $(@F)
 
@@ -1225,19 +1256,19 @@ $(srcdir)/ext/rbconfig/sizeof/limits.c: $(srcdir)/ext/rbconfig/sizeof/depend \
 		$(tooldir)/generic_erb.rb $(srcdir)/template/limits.c.tmpl
 	$(ECHO) generating $@
 	$(Q) $(CHDIR) $(@D) && \
-	sed '/AUTOGENERATED/q' depend | \
+	$(CAT_DEPEND) depend | \
 	$(exec) $(MAKE) -f - $(mflags) \
 		Q=$(Q) ECHO=$(ECHO) top_srcdir=../../.. srcdir=. VPATH=../../.. RUBY="$(BASERUBY)" $(@F)
 
 $(srcdir)/ext/socket/constdefs.c: $(srcdir)/ext/socket/depend
 	$(Q) $(CHDIR) $(@D) && \
-	sed '/AUTOGENERATED/q' depend | \
+	$(CAT_DEPEND) depend | \
 	$(exec) $(MAKE) -f - $(mflags) \
 		Q=$(Q) ECHO=$(ECHO) top_srcdir=../.. srcdir=. VPATH=../.. RUBY="$(BASERUBY)"
 
 $(srcdir)/ext/etc/constdefs.h: $(srcdir)/ext/etc/depend
 	$(Q) $(CHDIR) $(@D) && \
-	sed '/AUTOGENERATED/q' depend | \
+	$(CAT_DEPEND) depend | \
 	$(exec) $(MAKE) -f - $(mflags) \
 		Q=$(Q) ECHO=$(ECHO) top_srcdir=../.. srcdir=. VPATH=../.. RUBY="$(BASERUBY)"
 
@@ -1309,7 +1340,7 @@ lldb-ruby: $(PROGRAM) PHONY
 DISTPKGS = gzip,zip,all
 PKGSDIR = tmp
 dist:
-	$(BASERUBY) $(tooldir)/make-snapshot \
+	$(BASERUBY) $(V0:1=-v) $(tooldir)/make-snapshot \
 	-srcdir=$(srcdir) -packages=$(DISTPKGS) \
 	-unicode-version=$(UNICODE_VERSION) \
 	$(DISTOPTS) $(PKGSDIR) $(RELNAME)
@@ -1322,10 +1353,15 @@ up::
 yes::
 no::
 
+after-update:: common-srcs
 after-update:: $(REVISION_H)
 after-update:: extract-extlibs
 after-update:: extract-gems
 
+update-src::
+	$(Q) $(RM) $(REVISION_H) revision.h "$(srcdir)/$(REVISION_H)" "$(srcdir)/revision.h"
+	$(Q) exit > "$(srcdir)/revision.h"
+
 update-remote:: update-src update-download
 update-download:: $(ALWAYS_UPDATE_UNICODE:yes=update-unicode)
 update-download:: update-gems
@@ -1340,8 +1376,9 @@ update-config_files: PHONY
 
 refresh-gems: update-bundled_gems prepare-gems
 prepare-gems: $(HAVE_BASERUBY:yes=update-gems) $(HAVE_BASERUBY:yes=extract-gems)
+extract-gems: $(HAVE_BASERUBY:yes=update-gems)
 
-update-gems$(gnumake:yes=-nongnumake): PHONY
+update-gems$(gnumake:yes=-sequential): PHONY
 	$(ECHO) Downloading bundled gem files...
 	$(Q) $(BASERUBY) -C "$(srcdir)" \
 	    -I./tool -rdownloader -answ \
@@ -1355,26 +1392,32 @@ update-gems$(gnumake:yes=-nongnumake): PHONY
 	    -e 'FileUtils.rm_rf(old.map{'"|n|"'n.chomp(".gem")})' \
 	    gems/bundled_gems
 
-extract-gems$(gnumake:yes=-nongnumake): PHONY
+extract-gems$(gnumake:yes=-sequential): PHONY
 	$(ECHO) Extracting bundled gem files...
-	$(Q) $(RUNRUBY) -C "$(srcdir)" \
-	    -Itool -rfileutils -rgem-unpack -answ \
-	    -e 'BEGIN {FileUtils.mkdir_p(d = ".bundle/gems")}' \
-	    -e 'BEGIN {FileUtils.mkdir_p(s = ".bundle/specifications")}' \
-	    -e 'gem, ver = *$$F' \
+	$(Q) $(BASERUBY) -C "$(srcdir)" \
+	    -Itool/lib -rfileutils -rbundled_gem -answ \
+	    -e 'BEGIN {d = ".bundle/gems"}' \
+	    -e 'gem, ver, _, rev = *$$F' \
 	    -e 'next if !ver or /^#/=~gem' \
 	    -e 'g = "#{gem}-#{ver}"' \
-	    -e 'File.directory?("#{d}/#{g}") or Gem.unpack("gems/#{g}.gem", d, s)' \
-	    -e 'FileUtils.rm_rf("#{d}/#{g}/.github")' \
+	    -e 'if File.directory?("#{d}/#{g}")' \
+	    -e 'elsif rev and File.exist?(gs = "gems/src/#{gem}/#{gem}.gemspec")' \
+	    -e   'BundledGem.copy(gs, ".bundle")' \
+	    -e 'else' \
+	    -e   'BundledGem.unpack("gems/#{g}.gem", ".bundle")' \
+	    -e 'end' \
 	    gems/bundled_gems
 
+outdate-bundled-gems: PHONY
+	$(Q) $(BASERUBY) $(tooldir)/$@.rb --make="$(MAKE)" --mflags="$(MFLAGS)" "$(srcdir)"
+
 update-bundled_gems: PHONY
 	$(Q) $(RUNRUBY) -rrubygems \
 	     $(tooldir)/update-bundled_gems.rb \
 	     "$(srcdir)/gems/bundled_gems" | \
 	$(IFCHANGE) "$(srcdir)/gems/bundled_gems" -
-	git -C "$(srcdir)" diff --no-ext-diff --ignore-submodules --exit-code || \
-	git -C "$(srcdir)" commit -m "Update bundled_gems" gems/bundled_gems
+	$(GIT) -C "$(srcdir)" diff --no-ext-diff --ignore-submodules --exit-code || \
+	$(GIT) -C "$(srcdir)" commit -m "Update bundled_gems" gems/bundled_gems
 
 PRECHECK_BUNDLED_GEMS = test-bundled-gems-precheck
 test-bundled-gems-precheck: $(TEST_RUNNABLE)-test-bundled-gems-precheck
@@ -1382,7 +1425,7 @@ yes-test-bundled-gems-precheck: main
 no-test-bundled-gems-precheck:
 
 test-bundled-gems-fetch: yes-test-bundled-gems-fetch
-yes-test-bundled-gems-fetch: $(PREP)
+yes-test-bundled-gems-fetch:
 	$(ACTIONS_GROUP)
 	$(Q) $(BASERUBY) -C $(srcdir)/gems ../tool/fetch-bundled_gems.rb src bundled_gems
 	$(ACTIONS_ENDGROUP)
@@ -1394,7 +1437,7 @@ no-test-bundled-gems-prepare: no-test-bundled-gems-precheck
 yes-test-bundled-gems-prepare: yes-test-bundled-gems-precheck
 	$(ACTIONS_GROUP)
 	$(XRUBY) -C "$(srcdir)" bin/gem install --no-document \
-		--install-dir .bundle --conservative "bundler" "minitest:~> 5" "test-unit" "rake" "hoe" "yard" "pry" "packnga" "rexml" "json-schema" "test-unit-rr"
+		--install-dir .bundle --conservative "bundler" "minitest:~> 5" "test-unit" "rake" "hoe" "rexml" "json-schema:5.1.0" "test-unit-rr"
 	$(ACTIONS_ENDGROUP)
 
 PREPARE_BUNDLED_GEMS = test-bundled-gems-prepare
@@ -1407,11 +1450,34 @@ no-test-bundled-gems:
 
 BUNDLED_GEMS =
 test-bundled-gems-run: $(PREPARE_BUNDLED_GEMS)
-	$(Q) $(XRUBY) $(tooldir)/test-bundled-gems.rb $(BUNDLED_GEMS)
+	$(gnumake_recursive)$(Q) $(XRUBY) $(tooldir)/test-bundled-gems.rb $(BUNDLED_GEMS)
+
+test-syntax-suggest-precheck: $(TEST_RUNNABLE)-test-syntax-suggest-precheck
+no-test-syntax-suggest-precheck:
+yes-test-syntax-suggest-precheck: main
+
+test-syntax-suggest-prepare: $(TEST_RUNNABLE)-test-syntax-suggest-prepare
+no-test-syntax-suggest-prepare: no-test-syntax-suggest-precheck
+yes-test-syntax-suggest-prepare: yes-test-syntax-suggest-precheck
+	$(ACTIONS_GROUP)
+	$(XRUBY) -C "$(srcdir)" bin/gem install --no-document \
+		--install-dir .bundle --conservative "bundler" "rake" "rspec:~> 3" #"ruby-prof"
+	$(ACTIONS_ENDGROUP)
+
+RSPECOPTS =
+SYNTAX_SUGGEST_SPECS =
+PREPARE_SYNTAX_SUGGEST = test-syntax-suggest-prepare
+test-syntax-suggest: $(TEST_RUNNABLE)-test-syntax-suggest
+yes-test-syntax-suggest: yes-$(PREPARE_SYNTAX_SUGGEST)
+	$(XRUBY) -C $(srcdir) -Ispec/syntax_suggest .bundle/bin/rspec \
+		--require spec_helper $(RSPECOPTS) spec/syntax_suggest/$(SYNTAX_SUGGEST_SPECS)
+no-test-syntax-suggest:
+
+check: $(DOT_WAIT) $(TEST_RUNNABLE)-$(PREPARE_SYNTAX_SUGGEST) test-syntax-suggest
 
 test-bundler-precheck: $(TEST_RUNNABLE)-test-bundler-precheck
 no-test-bundler-precheck:
-yes-test-bundler-precheck: main
+yes-test-bundler-precheck: main $(arch)-fake.rb
 
 no-test-bundler-prepare: no-test-bundler-precheck
 yes-test-bundler-prepare: yes-test-bundler-precheck
@@ -1428,14 +1494,18 @@ RSPECOPTS =
 BUNDLER_SPECS =
 test-bundler: $(TEST_RUNNABLE)-test-bundler
 yes-test-bundler: yes-test-bundler-prepare
-	$(XRUBY) -C $(srcdir) -Ispec/bundler .bundle/bin/rspec \
+	$(gnumake_recursive)$(XRUBY) \
+		-r./$(arch)-fake \
+		-e "exec(*ARGV)" -- \
+		$(XRUBY) -C $(srcdir) -Ispec/bundler .bundle/bin/rspec \
 		--require spec_helper $(RSPECOPTS) spec/bundler/$(BUNDLER_SPECS)
 no-test-bundler:
 
 PARALLELRSPECOPTS = --runtime-log $(srcdir)/tmp/parallel_runtime_rspec.log
 test-bundler-parallel: $(TEST_RUNNABLE)-test-bundler-parallel
 yes-test-bundler-parallel: yes-test-bundler-prepare
-	$(XRUBY) \
+	$(gnumake_recursive)$(XRUBY) \
+		-r./$(arch)-fake \
 		-e "ARGV[-1] = File.expand_path(ARGV[-1])" \
 		-e "exec(*ARGV)" -- \
 		$(XRUBY) -I$(srcdir)/spec/bundler \
@@ -1447,6 +1517,12 @@ yes-test-bundler-parallel: yes-test-bundler-prepare
 		$(PARALLELRSPECOPTS) $(srcdir)/spec/bundler/$(BUNDLER_SPECS)
 no-test-bundler-parallel:
 
+# The annocheck supports ELF format binaries compiled for any OS and for any
+# architecture. It is designed to be independent of the host OS and the
+# architecture. The test-annocheck.sh requires docker or podman.
+test-annocheck: $(PROGRAM)
+	$(tooldir)/test-annocheck.sh $(PROGRAM)
+
 GEM = up
 sync-default-gems:
 	$(Q) $(XRUBY) -C "$(srcdir)" tool/sync_default_gems.rb $(GEM)
@@ -1488,60 +1564,54 @@ update-unicode: $(UNICODE_FILES) $(UNICODE_PROPERTY_FILES) \
 		$(UNICODE_AUXILIARY_FILES) $(UNICODE_UCD_EMOJI_FILES) $(UNICODE_EMOJI_FILES)
 
 CACHE_DIR = $(srcdir)/.downloaded-cache
-UNICODE_DOWNLOAD = \
+UNICODE_DOWNLOADER_ALWAYS_UPDATE = $(ALWAYS_UPDATE_UNICODE:yes=--always)
+UNICODE_DOWNLOADER = \
 	$(BASERUBY) $(tooldir)/downloader.rb \
 	    --cache-dir=$(CACHE_DIR) \
-	    --unicode-beta $(UNICODE_BETA) \
+	    --exist $(UNICODE_DOWNLOADER_ALWAYS_UPDATE:no=) \
+	    unicode --unicode-beta=$(UNICODE_BETA)
+UNICODE_DOWNLOAD = \
+	$(UNICODE_DOWNLOADER) \
 	    -d $(UNICODE_SRC_DATA_DIR) \
-	    -p $(UNICODE_VERSION)/ucd \
-	    -e $(ALWAYS_UPDATE_UNICODE:yes=-a) unicode
+	    -p $(UNICODE_VERSION)/ucd
 UNICODE_AUXILIARY_DOWNLOAD = \
-	$(BASERUBY) $(tooldir)/downloader.rb \
-	    --cache-dir=$(CACHE_DIR) \
-	    --unicode-beta $(UNICODE_BETA) \
+	$(UNICODE_DOWNLOADER) \
 	    -d $(UNICODE_SRC_DATA_DIR)/auxiliary \
-	    -p $(UNICODE_VERSION)/ucd/auxiliary \
-	    -e $(ALWAYS_UPDATE_UNICODE:yes=-a) unicode
+	    -p $(UNICODE_VERSION)/ucd/auxiliary
 UNICODE_UCD_EMOJI_DOWNLOAD = \
-	$(BASERUBY) $(tooldir)/downloader.rb \
-	    --cache-dir=$(CACHE_DIR) \
-	    --unicode-beta $(UNICODE_BETA) \
+	$(UNICODE_DOWNLOADER) \
 	    -d $(UNICODE_SRC_DATA_DIR)/emoji \
-	    -p $(UNICODE_VERSION)/ucd/emoji \
-	    -e $(ALWAYS_UPDATE_UNICODE:yes=-a) unicode
+	    -p $(UNICODE_VERSION)/ucd/emoji
 UNICODE_EMOJI_DOWNLOAD = \
-	$(BASERUBY) $(tooldir)/downloader.rb \
-	    --cache-dir=$(CACHE_DIR) \
-	    --unicode-beta $(UNICODE_BETA) \
+	$(UNICODE_DOWNLOADER) \
 	    -d $(UNICODE_SRC_EMOJI_DATA_DIR) \
-	    -p emoji/$(UNICODE_EMOJI_VERSION) \
-	    -e $(ALWAYS_UPDATE_UNICODE:yes=-a) unicode
+	    -p emoji/$(UNICODE_EMOJI_VERSION)
 
-$(UNICODE_FILES) $(UNICODE_PROPERTY_FILES): update-unicode-files
-update-unicode-files:
+update-unicode-files: $(UNICODE_FILES) $(UNICODE_PROPERTY_FILES)
+$(UNICODE_FILES) $(UNICODE_PROPERTY_FILES):
 	$(ECHO) Downloading Unicode $(UNICODE_VERSION) data and property files...
 	$(Q) $(MAKEDIRS) "$(UNICODE_SRC_DATA_DIR)"
 	$(Q) $(UNICODE_DOWNLOAD) $(UNICODE_FILES) $(UNICODE_PROPERTY_FILES)
 
-$(UNICODE_AUXILIARY_FILES): update-unicode-auxiliary-files
-update-unicode-auxiliary-files:
+update-unicode-auxiliary-files: $(UNICODE_AUXILIARY_FILES)
+$(UNICODE_AUXILIARY_FILES):
 	$(ECHO) Downloading Unicode $(UNICODE_VERSION) auxiliary files...
 	$(Q) $(MAKEDIRS) "$(UNICODE_SRC_DATA_DIR)/auxiliary"
 	$(Q) $(UNICODE_AUXILIARY_DOWNLOAD) $(UNICODE_AUXILIARY_FILES)
 
-$(UNICODE_UCD_EMOJI_FILES): update-unicode-ucd-emoji-files
-update-unicode-ucd-emoji-files:
+update-unicode-ucd-emoji-files: $(UNICODE_UCD_EMOJI_FILES)
+$(UNICODE_UCD_EMOJI_FILES):
 	$(ECHO) Downloading Unicode UCD emoji $(UNICODE_EMOJI_VERSION) files...
 	$(Q) $(MAKEDIRS) "$(UNICODE_SRC_DATA_DIR)/emoji"
 	$(Q) $(UNICODE_UCD_EMOJI_DOWNLOAD) $(UNICODE_UCD_EMOJI_FILES)
 
-$(UNICODE_EMOJI_FILES): update-unicode-emoji-files
-update-unicode-emoji-files:
+update-unicode-emoji-files: $(UNICODE_EMOJI_FILES)
+$(UNICODE_EMOJI_FILES):
 	$(ECHO) Downloading Unicode emoji $(UNICODE_EMOJI_VERSION) files...
 	$(Q) $(MAKEDIRS) "$(UNICODE_SRC_EMOJI_DATA_DIR)"
 	$(Q) $(UNICODE_EMOJI_DOWNLOAD) $(UNICODE_EMOJI_FILES)
 
-$(srcdir)/lib/unicode_normalize/$(ALWAYS_UPDATE_UNICODE:yes=tables.rb): \
+$(srcdir)/lib/unicode_normalize/tables.rb: \
 	$(UNICODE_SRC_DATA_DIR)/$(HAVE_BASERUBY:yes=.unicode-tables.time)
 
 $(UNICODE_SRC_DATA_DIR)/$(ALWAYS_UPDATE_UNICODE:yes=.unicode-tables.time): \
@@ -1550,13 +1620,25 @@ $(UNICODE_SRC_DATA_DIR)/$(ALWAYS_UPDATE_UNICODE:yes=.unicode-tables.time): \
 
 touch-unicode-files:
 	$(MAKEDIRS) $(UNICODE_SRC_DATA_DIR)
-	touch $(UNICODE_SRC_DATA_DIR)/.unicode-tables.time $(UNICODE_DATA_HEADERS)
+	$(Q) $(TOUCH) $(UNICODE_SRC_DATA_DIR)/.unicode-tables.time $(UNICODE_DATA_HEADERS)
 
+UNICODE_TABLES_DATA_FILES = \
+	$(UNICODE_SRC_DATA_DIR)/UnicodeData.txt \
+	$(UNICODE_SRC_DATA_DIR)/CompositionExclusions.txt \
+	$(empty)
+
+UNICODE_TABLES_DEPENDENTS_1 = none$(ALWAYS_UPDATE_UNICODE)
+UNICODE_TABLES_DEPENDENTS = $(UNICODE_TABLES_DEPENDENTS_1:noneyes=force)
 UNICODE_TABLES_TIMESTAMP = yes
-$(UNICODE_SRC_DATA_DIR)/.unicode-tables.time: $(tooldir)/generic_erb.rb \
+$(UNICODE_SRC_DATA_DIR)/.unicode-tables.$(UNICODE_TABLES_DEPENDENTS:none=time):
+	$(Q) $(MAKEDIRS) $(@D)
+	$(Q) exit > $(@) || $(NULLCMD)
+$(UNICODE_SRC_DATA_DIR)/.unicode-tables.$(UNICODE_TABLES_DEPENDENTS:force=time): \
+		$(tooldir)/generic_erb.rb \
 		$(srcdir)/template/unicode_norm_gen.tmpl \
-		$(ALWAYS_UPDATE_UNICODE:yes=update-unicode)
-	$(Q) $(MAKE) $(@D)
+		$(UNICODE_TABLES_DATA_FILES) \
+	$(order_only) \
+		$(UNICODE_SRC_DATA_DIR)
 	$(Q) $(BASERUBY) $(tooldir)/generic_erb.rb \
 		-c $(UNICODE_TABLES_TIMESTAMP:yes=-t$@) \
 		-o $(srcdir)/lib/unicode_normalize/tables.rb \
@@ -1582,19 +1664,19 @@ $(UNICODE_HDR_DIR)/name2ctype.h:
 	$(MV) $@.new $@
 
 # the next non-comment line was:
-# $(UNICODE_HDR_DIR)/casefold.h: $(srcdir)/enc/unicode/case-folding.rb \
+# $(UNICODE_HDR_DIR)/casefold.h: $(tooldir)/enc-case-folding.rb \
 # but was changed to make sure CI works on systems that don't have gperf
 unicode-up: $(UNICODE_DATA_HEADERS)
 
 $(UNICODE_HDR_DIR)/$(ALWAYS_UPDATE_UNICODE:yes=casefold.h): \
-		$(srcdir)/enc/unicode/case-folding.rb \
+		$(tooldir)/enc-case-folding.rb \
 		$(UNICODE_SRC_DATA_DIR)/UnicodeData.txt \
 		$(UNICODE_SRC_DATA_DIR)/SpecialCasing.txt \
 		$(UNICODE_SRC_DATA_DIR)/CaseFolding.txt
 
 $(UNICODE_HDR_DIR)/casefold.h:
 	$(MAKEDIRS) $(@D)
-	$(Q) $(BASERUBY) $(srcdir)/enc/unicode/case-folding.rb \
+	$(Q) $(BASERUBY) $(tooldir)/enc-case-folding.rb \
 		--output-file=$@ \
 		--mapping-data-directory=$(UNICODE_SRC_DATA_DIR)
 
@@ -1654,41 +1736,45 @@ help: PHONY
 	"                Makefile of Ruby" \
 	"" \
 	"targets:" \
-	"  all (default):       builds all of below" \
-	"  miniruby:            builds only miniruby" \
-	"  encs:                builds encodings" \
-	"  exts:                builds extensions" \
-	"  main:                builds encodings, extensions and ruby" \
-	"  docs:                builds documents" \
-	"  install-capi:        builds C API documents" \
-	"  run:                 runs test.rb by miniruby" \
-	"  runruby:             runs test.rb by ruby you just built" \
-	"  gdb:                 runs test.rb by miniruby under gdb" \
-	"  gdb-ruby:            runs test.rb by ruby under gdb" \
-	"  check:               equals make test test-tool test-all test-spec" \
-	"  test:                ruby core tests [BTESTS=<bootstraptest files>]" \
-	"  test-all:            all ruby tests [TESTOPTS=-j4 TESTS=<test files>]" \
-	"  test-spec:           run the Ruby spec suite [SPECOPTS=<specs, opts>]" \
-	"  test-bundler:        run the Bundler spec" \
-	"  test-bundled-gems:   run the test suite of bundled gems" \
-	"  test-tool:           tests under the tool/test" \
-	"  update-gems:         download files of the bundled gems" \
-	"  update-bundled_gems: update the latest version of bundled gems" \
-	"  sync-default-gems:   sync default gems from upstream [GEM=<gem_name git_ref>]" \
-	"  up:                  update local copy and autogenerated files" \
-	"  benchmark:           benchmark this ruby and COMPARE_RUBY." \
-	"  gcbench:             gc benchmark [GCBENCH_ITEM=<item_name>]" \
-	"  install:             install all ruby distributions" \
-	"  install-nodoc:       install without rdoc" \
-	"  install-cross:       install cross compiling stuff" \
-	"  clean:               clean for tarball" \
-	"  distclean:           clean for repository" \
-	"  golf:                build goruby for golfers" \
+	"  all (default):         builds all of below" \
+	"  miniruby:              builds only miniruby" \
+	"  encs:                  builds encodings" \
+	"  exts:                  builds extensions" \
+	"  main:                  builds encodings, extensions and ruby" \
+	"  docs:                  builds documents" \
+	"  install-capi:          builds C API documents" \
+	"  run:                   runs test.rb by miniruby" \
+	"  runruby:               runs test.rb by ruby you just built" \
+	"  gdb:                   runs test.rb by miniruby under gdb" \
+	"  gdb-ruby:              runs test.rb by ruby under gdb" \
+	"  check:                 equals make test test-tool test-all test-spec" \
+	"  test:                  ruby core tests [BTESTS=<bootstraptest files>]" \
+	"  test-all:              all ruby tests [TESTOPTS=-j4 TESTS=<test files>]" \
+	"  test-spec:             run the Ruby spec suite [SPECOPTS=<specs, opts>]" \
+	"  test-bundler:          run the Bundler spec" \
+	"  test-bundler-parallel: run the Bundler spec with parallel" \
+	"  test-bundled-gems:     run the test suite of bundled gems" \
+	"  test-tool:             tests under the tool/test" \
+	"  update-gems:           download files of the bundled gems" \
+	"  update-bundled_gems:   update the latest version of bundled gems" \
+	"  sync-default-gems:     sync default gems from upstream [GEM=<gem_name git_ref>]" \
+	"  up:                    update local copy and autogenerated files" \
+	"  benchmark:             benchmark this ruby and COMPARE_RUBY." \
+	"  gcbench:               gc benchmark [GCBENCH_ITEM=<item_name>]" \
+	"  install:               install all ruby distributions" \
+	"  install-nodoc:         install without rdoc" \
+	"  install-cross:         install cross compiling stuff" \
+	"  clean:                 clean for tarball" \
+	"  distclean:             clean for repository" \
+	"  golf:                  build goruby for golfers" \
 	$(HELP_EXTRA_TASKS) \
 	"see DeveloperHowto for more detail: " \
 	"  https://bugs.ruby-lang.org/projects/ruby/wiki/DeveloperHowto" \
 	$(MESSAGE_END)
 
+$(CROSS_COMPILING:yes=)builtin.$(OBJEXT): {$(VPATH)}mini_builtin.c
+$(CROSS_COMPILING:yes=)builtin.$(OBJEXT): {$(VPATH)}miniprelude.c
+
 # AUTOGENERATED DEPENDENCIES START
 addr2line.$(OBJEXT): {$(VPATH)}addr2line.c
 addr2line.$(OBJEXT): {$(VPATH)}addr2line.h
@@ -1746,6 +1832,7 @@ addr2line.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
 addr2line.$(OBJEXT): {$(VPATH)}missing.h
 array.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 array.$(OBJEXT): $(top_srcdir)/internal/array.h
+array.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 array.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 array.$(OBJEXT): $(top_srcdir)/internal/bits.h
 array.$(OBJEXT): $(top_srcdir)/internal/class.h
@@ -1761,6 +1848,7 @@ array.$(OBJEXT): $(top_srcdir)/internal/proc.h
 array.$(OBJEXT): $(top_srcdir)/internal/rational.h
 array.$(OBJEXT): $(top_srcdir)/internal/serial.h
 array.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
+array.$(OBJEXT): $(top_srcdir)/internal/variable.h
 array.$(OBJEXT): $(top_srcdir)/internal/vm.h
 array.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 array.$(OBJEXT): {$(VPATH)}array.c
@@ -1777,6 +1865,7 @@ array.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 array.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 array.$(OBJEXT): {$(VPATH)}builtin.h
 array.$(OBJEXT): {$(VPATH)}config.h
+array.$(OBJEXT): {$(VPATH)}constant.h
 array.$(OBJEXT): {$(VPATH)}debug_counter.h
 array.$(OBJEXT): {$(VPATH)}defines.h
 array.$(OBJEXT): {$(VPATH)}encoding.h
@@ -1939,6 +2028,7 @@ array.$(OBJEXT): {$(VPATH)}oniguruma.h
 array.$(OBJEXT): {$(VPATH)}probes.dmyh
 array.$(OBJEXT): {$(VPATH)}probes.h
 array.$(OBJEXT): {$(VPATH)}ruby_assert.h
+array.$(OBJEXT): {$(VPATH)}shape.h
 array.$(OBJEXT): {$(VPATH)}st.h
 array.$(OBJEXT): {$(VPATH)}subst.h
 array.$(OBJEXT): {$(VPATH)}transient_heap.h
@@ -1950,6 +2040,7 @@ ast.$(OBJEXT): $(CCAN_DIR)/str/str.h
 ast.$(OBJEXT): $(hdrdir)/ruby.h
 ast.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 ast.$(OBJEXT): $(top_srcdir)/internal/array.h
+ast.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 ast.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 ast.$(OBJEXT): $(top_srcdir)/internal/gc.h
 ast.$(OBJEXT): $(top_srcdir)/internal/imemo.h
@@ -1957,6 +2048,7 @@ ast.$(OBJEXT): $(top_srcdir)/internal/parse.h
 ast.$(OBJEXT): $(top_srcdir)/internal/serial.h
 ast.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 ast.$(OBJEXT): $(top_srcdir)/internal/symbol.h
+ast.$(OBJEXT): $(top_srcdir)/internal/variable.h
 ast.$(OBJEXT): $(top_srcdir)/internal/vm.h
 ast.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 ast.$(OBJEXT): {$(VPATH)}assert.h
@@ -1974,10 +2066,11 @@ ast.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 ast.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 ast.$(OBJEXT): {$(VPATH)}builtin.h
 ast.$(OBJEXT): {$(VPATH)}config.h
-ast.$(OBJEXT): {$(VPATH)}darray.h
+ast.$(OBJEXT): {$(VPATH)}constant.h
 ast.$(OBJEXT): {$(VPATH)}defines.h
 ast.$(OBJEXT): {$(VPATH)}encoding.h
 ast.$(OBJEXT): {$(VPATH)}id.h
+ast.$(OBJEXT): {$(VPATH)}id_table.h
 ast.$(OBJEXT): {$(VPATH)}intern.h
 ast.$(OBJEXT): {$(VPATH)}internal.h
 ast.$(OBJEXT): {$(VPATH)}internal/abi.h
@@ -2137,6 +2230,7 @@ ast.$(OBJEXT): {$(VPATH)}onigmo.h
 ast.$(OBJEXT): {$(VPATH)}oniguruma.h
 ast.$(OBJEXT): {$(VPATH)}ruby_assert.h
 ast.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+ast.$(OBJEXT): {$(VPATH)}shape.h
 ast.$(OBJEXT): {$(VPATH)}st.h
 ast.$(OBJEXT): {$(VPATH)}subst.h
 ast.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -2320,6 +2414,7 @@ bignum.$(OBJEXT): {$(VPATH)}internal/warning_push.h
 bignum.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
 bignum.$(OBJEXT): {$(VPATH)}missing.h
 bignum.$(OBJEXT): {$(VPATH)}ruby_assert.h
+bignum.$(OBJEXT): {$(VPATH)}shape.h
 bignum.$(OBJEXT): {$(VPATH)}st.h
 bignum.$(OBJEXT): {$(VPATH)}subst.h
 bignum.$(OBJEXT): {$(VPATH)}thread.h
@@ -2330,11 +2425,13 @@ builtin.$(OBJEXT): $(CCAN_DIR)/list/list.h
 builtin.$(OBJEXT): $(CCAN_DIR)/str/str.h
 builtin.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 builtin.$(OBJEXT): $(top_srcdir)/internal/array.h
+builtin.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 builtin.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 builtin.$(OBJEXT): $(top_srcdir)/internal/gc.h
 builtin.$(OBJEXT): $(top_srcdir)/internal/imemo.h
 builtin.$(OBJEXT): $(top_srcdir)/internal/serial.h
 builtin.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
+builtin.$(OBJEXT): $(top_srcdir)/internal/variable.h
 builtin.$(OBJEXT): $(top_srcdir)/internal/vm.h
 builtin.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 builtin.$(OBJEXT): {$(VPATH)}assert.h
@@ -2352,9 +2449,10 @@ builtin.$(OBJEXT): {$(VPATH)}builtin.c
 builtin.$(OBJEXT): {$(VPATH)}builtin.h
 builtin.$(OBJEXT): {$(VPATH)}builtin_binary.inc
 builtin.$(OBJEXT): {$(VPATH)}config.h
-builtin.$(OBJEXT): {$(VPATH)}darray.h
+builtin.$(OBJEXT): {$(VPATH)}constant.h
 builtin.$(OBJEXT): {$(VPATH)}defines.h
 builtin.$(OBJEXT): {$(VPATH)}id.h
+builtin.$(OBJEXT): {$(VPATH)}id_table.h
 builtin.$(OBJEXT): {$(VPATH)}intern.h
 builtin.$(OBJEXT): {$(VPATH)}internal.h
 builtin.$(OBJEXT): {$(VPATH)}internal/abi.h
@@ -2503,6 +2601,7 @@ builtin.$(OBJEXT): {$(VPATH)}missing.h
 builtin.$(OBJEXT): {$(VPATH)}node.h
 builtin.$(OBJEXT): {$(VPATH)}ruby_assert.h
 builtin.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+builtin.$(OBJEXT): {$(VPATH)}shape.h
 builtin.$(OBJEXT): {$(VPATH)}st.h
 builtin.$(OBJEXT): {$(VPATH)}subst.h
 builtin.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -2515,6 +2614,7 @@ class.$(OBJEXT): $(CCAN_DIR)/list/list.h
 class.$(OBJEXT): $(CCAN_DIR)/str/str.h
 class.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 class.$(OBJEXT): $(top_srcdir)/internal/array.h
+class.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 class.$(OBJEXT): $(top_srcdir)/internal/class.h
 class.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 class.$(OBJEXT): $(top_srcdir)/internal/eval.h
@@ -2542,7 +2642,6 @@ class.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 class.$(OBJEXT): {$(VPATH)}class.c
 class.$(OBJEXT): {$(VPATH)}config.h
 class.$(OBJEXT): {$(VPATH)}constant.h
-class.$(OBJEXT): {$(VPATH)}darray.h
 class.$(OBJEXT): {$(VPATH)}debug_counter.h
 class.$(OBJEXT): {$(VPATH)}defines.h
 class.$(OBJEXT): {$(VPATH)}encoding.h
@@ -2706,6 +2805,7 @@ class.$(OBJEXT): {$(VPATH)}onigmo.h
 class.$(OBJEXT): {$(VPATH)}oniguruma.h
 class.$(OBJEXT): {$(VPATH)}ruby_assert.h
 class.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+class.$(OBJEXT): {$(VPATH)}shape.h
 class.$(OBJEXT): {$(VPATH)}st.h
 class.$(OBJEXT): {$(VPATH)}subst.h
 class.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -2713,6 +2813,7 @@ class.$(OBJEXT): {$(VPATH)}thread_native.h
 class.$(OBJEXT): {$(VPATH)}vm_core.h
 class.$(OBJEXT): {$(VPATH)}vm_opts.h
 compar.$(OBJEXT): $(hdrdir)/ruby/ruby.h
+compar.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 compar.$(OBJEXT): $(top_srcdir)/internal/compar.h
 compar.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 compar.$(OBJEXT): $(top_srcdir)/internal/error.h
@@ -2897,6 +2998,7 @@ compile.$(OBJEXT): $(CCAN_DIR)/list/list.h
 compile.$(OBJEXT): $(CCAN_DIR)/str/str.h
 compile.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 compile.$(OBJEXT): $(top_srcdir)/internal/array.h
+compile.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 compile.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 compile.$(OBJEXT): $(top_srcdir)/internal/bits.h
 compile.$(OBJEXT): $(top_srcdir)/internal/class.h
@@ -2936,7 +3038,6 @@ compile.$(OBJEXT): {$(VPATH)}builtin.h
 compile.$(OBJEXT): {$(VPATH)}compile.c
 compile.$(OBJEXT): {$(VPATH)}config.h
 compile.$(OBJEXT): {$(VPATH)}constant.h
-compile.$(OBJEXT): {$(VPATH)}darray.h
 compile.$(OBJEXT): {$(VPATH)}debug_counter.h
 compile.$(OBJEXT): {$(VPATH)}defines.h
 compile.$(OBJEXT): {$(VPATH)}encindex.h
@@ -3110,6 +3211,7 @@ compile.$(OBJEXT): {$(VPATH)}re.h
 compile.$(OBJEXT): {$(VPATH)}regex.h
 compile.$(OBJEXT): {$(VPATH)}ruby_assert.h
 compile.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+compile.$(OBJEXT): {$(VPATH)}shape.h
 compile.$(OBJEXT): {$(VPATH)}st.h
 compile.$(OBJEXT): {$(VPATH)}subst.h
 compile.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -3119,8 +3221,13 @@ compile.$(OBJEXT): {$(VPATH)}vm_callinfo.h
 compile.$(OBJEXT): {$(VPATH)}vm_core.h
 compile.$(OBJEXT): {$(VPATH)}vm_debug.h
 compile.$(OBJEXT): {$(VPATH)}vm_opts.h
+complex.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h
+complex.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h
+complex.$(OBJEXT): $(CCAN_DIR)/list/list.h
+complex.$(OBJEXT): $(CCAN_DIR)/str/str.h
 complex.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 complex.$(OBJEXT): $(top_srcdir)/internal/array.h
+complex.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 complex.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 complex.$(OBJEXT): $(top_srcdir)/internal/bits.h
 complex.$(OBJEXT): $(top_srcdir)/internal/class.h
@@ -3128,15 +3235,18 @@ complex.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 complex.$(OBJEXT): $(top_srcdir)/internal/complex.h
 complex.$(OBJEXT): $(top_srcdir)/internal/fixnum.h
 complex.$(OBJEXT): $(top_srcdir)/internal/gc.h
+complex.$(OBJEXT): $(top_srcdir)/internal/imemo.h
 complex.$(OBJEXT): $(top_srcdir)/internal/math.h
 complex.$(OBJEXT): $(top_srcdir)/internal/numeric.h
 complex.$(OBJEXT): $(top_srcdir)/internal/object.h
 complex.$(OBJEXT): $(top_srcdir)/internal/rational.h
 complex.$(OBJEXT): $(top_srcdir)/internal/serial.h
 complex.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
+complex.$(OBJEXT): $(top_srcdir)/internal/variable.h
 complex.$(OBJEXT): $(top_srcdir)/internal/vm.h
 complex.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 complex.$(OBJEXT): {$(VPATH)}assert.h
+complex.$(OBJEXT): {$(VPATH)}atomic.h
 complex.$(OBJEXT): {$(VPATH)}backward/2/assume.h
 complex.$(OBJEXT): {$(VPATH)}backward/2/attributes.h
 complex.$(OBJEXT): {$(VPATH)}backward/2/bool.h
@@ -3148,6 +3258,7 @@ complex.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 complex.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 complex.$(OBJEXT): {$(VPATH)}complex.c
 complex.$(OBJEXT): {$(VPATH)}config.h
+complex.$(OBJEXT): {$(VPATH)}constant.h
 complex.$(OBJEXT): {$(VPATH)}defines.h
 complex.$(OBJEXT): {$(VPATH)}id.h
 complex.$(OBJEXT): {$(VPATH)}id_table.h
@@ -3293,10 +3404,18 @@ complex.$(OBJEXT): {$(VPATH)}internal/value_type.h
 complex.$(OBJEXT): {$(VPATH)}internal/variable.h
 complex.$(OBJEXT): {$(VPATH)}internal/warning_push.h
 complex.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
+complex.$(OBJEXT): {$(VPATH)}method.h
 complex.$(OBJEXT): {$(VPATH)}missing.h
+complex.$(OBJEXT): {$(VPATH)}node.h
 complex.$(OBJEXT): {$(VPATH)}ruby_assert.h
+complex.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+complex.$(OBJEXT): {$(VPATH)}shape.h
 complex.$(OBJEXT): {$(VPATH)}st.h
 complex.$(OBJEXT): {$(VPATH)}subst.h
+complex.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
+complex.$(OBJEXT): {$(VPATH)}thread_native.h
+complex.$(OBJEXT): {$(VPATH)}vm_core.h
+complex.$(OBJEXT): {$(VPATH)}vm_opts.h
 cont.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h
 cont.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h
 cont.$(OBJEXT): $(CCAN_DIR)/list/list.h
@@ -3304,13 +3423,18 @@ cont.$(OBJEXT): $(CCAN_DIR)/str/str.h
 cont.$(OBJEXT): $(hdrdir)/ruby.h
 cont.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 cont.$(OBJEXT): $(top_srcdir)/internal/array.h
+cont.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 cont.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 cont.$(OBJEXT): $(top_srcdir)/internal/cont.h
+cont.$(OBJEXT): $(top_srcdir)/internal/error.h
 cont.$(OBJEXT): $(top_srcdir)/internal/gc.h
 cont.$(OBJEXT): $(top_srcdir)/internal/imemo.h
 cont.$(OBJEXT): $(top_srcdir)/internal/proc.h
+cont.$(OBJEXT): $(top_srcdir)/internal/sanitizers.h
 cont.$(OBJEXT): $(top_srcdir)/internal/serial.h
 cont.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
+cont.$(OBJEXT): $(top_srcdir)/internal/string.h
+cont.$(OBJEXT): $(top_srcdir)/internal/variable.h
 cont.$(OBJEXT): $(top_srcdir)/internal/vm.h
 cont.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 cont.$(OBJEXT): {$(VPATH)}$(COROUTINE_H)
@@ -3326,10 +3450,11 @@ cont.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 cont.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 cont.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 cont.$(OBJEXT): {$(VPATH)}config.h
+cont.$(OBJEXT): {$(VPATH)}constant.h
 cont.$(OBJEXT): {$(VPATH)}cont.c
-cont.$(OBJEXT): {$(VPATH)}darray.h
 cont.$(OBJEXT): {$(VPATH)}debug_counter.h
 cont.$(OBJEXT): {$(VPATH)}defines.h
+cont.$(OBJEXT): {$(VPATH)}encoding.h
 cont.$(OBJEXT): {$(VPATH)}eval_intern.h
 cont.$(OBJEXT): {$(VPATH)}fiber/scheduler.h
 cont.$(OBJEXT): {$(VPATH)}gc.h
@@ -3407,6 +3532,15 @@ cont.$(OBJEXT): {$(VPATH)}internal/core/rtypeddata.h
 cont.$(OBJEXT): {$(VPATH)}internal/ctype.h
 cont.$(OBJEXT): {$(VPATH)}internal/dllexport.h
 cont.$(OBJEXT): {$(VPATH)}internal/dosish.h
+cont.$(OBJEXT): {$(VPATH)}internal/encoding/coderange.h
+cont.$(OBJEXT): {$(VPATH)}internal/encoding/ctype.h
+cont.$(OBJEXT): {$(VPATH)}internal/encoding/encoding.h
+cont.$(OBJEXT): {$(VPATH)}internal/encoding/pathname.h
+cont.$(OBJEXT): {$(VPATH)}internal/encoding/re.h
+cont.$(OBJEXT): {$(VPATH)}internal/encoding/sprintf.h
+cont.$(OBJEXT): {$(VPATH)}internal/encoding/string.h
+cont.$(OBJEXT): {$(VPATH)}internal/encoding/symbol.h
+cont.$(OBJEXT): {$(VPATH)}internal/encoding/transcode.h
 cont.$(OBJEXT): {$(VPATH)}internal/error.h
 cont.$(OBJEXT): {$(VPATH)}internal/eval.h
 cont.$(OBJEXT): {$(VPATH)}internal/event.h
@@ -3477,14 +3611,18 @@ cont.$(OBJEXT): {$(VPATH)}internal/value_type.h
 cont.$(OBJEXT): {$(VPATH)}internal/variable.h
 cont.$(OBJEXT): {$(VPATH)}internal/warning_push.h
 cont.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
+cont.$(OBJEXT): {$(VPATH)}iseq.h
 cont.$(OBJEXT): {$(VPATH)}method.h
 cont.$(OBJEXT): {$(VPATH)}missing.h
 cont.$(OBJEXT): {$(VPATH)}mjit.h
 cont.$(OBJEXT): {$(VPATH)}node.h
+cont.$(OBJEXT): {$(VPATH)}onigmo.h
+cont.$(OBJEXT): {$(VPATH)}oniguruma.h
 cont.$(OBJEXT): {$(VPATH)}ractor.h
 cont.$(OBJEXT): {$(VPATH)}ractor_core.h
 cont.$(OBJEXT): {$(VPATH)}ruby_assert.h
 cont.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+cont.$(OBJEXT): {$(VPATH)}shape.h
 cont.$(OBJEXT): {$(VPATH)}st.h
 cont.$(OBJEXT): {$(VPATH)}subst.h
 cont.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -3492,6 +3630,7 @@ cont.$(OBJEXT): {$(VPATH)}thread_native.h
 cont.$(OBJEXT): {$(VPATH)}vm_core.h
 cont.$(OBJEXT): {$(VPATH)}vm_debug.h
 cont.$(OBJEXT): {$(VPATH)}vm_opts.h
+cont.$(OBJEXT): {$(VPATH)}vm_sync.h
 cont.$(OBJEXT): {$(VPATH)}yjit.h
 debug.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h
 debug.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h
@@ -3499,12 +3638,15 @@ debug.$(OBJEXT): $(CCAN_DIR)/list/list.h
 debug.$(OBJEXT): $(CCAN_DIR)/str/str.h
 debug.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 debug.$(OBJEXT): $(top_srcdir)/internal/array.h
+debug.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
+debug.$(OBJEXT): $(top_srcdir)/internal/class.h
 debug.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 debug.$(OBJEXT): $(top_srcdir)/internal/gc.h
 debug.$(OBJEXT): $(top_srcdir)/internal/imemo.h
 debug.$(OBJEXT): $(top_srcdir)/internal/serial.h
 debug.$(OBJEXT): $(top_srcdir)/internal/signal.h
 debug.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
+debug.$(OBJEXT): $(top_srcdir)/internal/variable.h
 debug.$(OBJEXT): $(top_srcdir)/internal/vm.h
 debug.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 debug.$(OBJEXT): {$(VPATH)}assert.h
@@ -3519,7 +3661,7 @@ debug.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 debug.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 debug.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 debug.$(OBJEXT): {$(VPATH)}config.h
-debug.$(OBJEXT): {$(VPATH)}darray.h
+debug.$(OBJEXT): {$(VPATH)}constant.h
 debug.$(OBJEXT): {$(VPATH)}debug.c
 debug.$(OBJEXT): {$(VPATH)}debug_counter.h
 debug.$(OBJEXT): {$(VPATH)}defines.h
@@ -3690,6 +3832,7 @@ debug.$(OBJEXT): {$(VPATH)}ractor.h
 debug.$(OBJEXT): {$(VPATH)}ractor_core.h
 debug.$(OBJEXT): {$(VPATH)}ruby_assert.h
 debug.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+debug.$(OBJEXT): {$(VPATH)}shape.h
 debug.$(OBJEXT): {$(VPATH)}st.h
 debug.$(OBJEXT): {$(VPATH)}subst.h
 debug.$(OBJEXT): {$(VPATH)}symbol.h
@@ -3874,6 +4017,7 @@ dir.$(OBJEXT): $(top_srcdir)/internal/object.h
 dir.$(OBJEXT): $(top_srcdir)/internal/serial.h
 dir.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 dir.$(OBJEXT): $(top_srcdir)/internal/string.h
+dir.$(OBJEXT): $(top_srcdir)/internal/variable.h
 dir.$(OBJEXT): $(top_srcdir)/internal/vm.h
 dir.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 dir.$(OBJEXT): {$(VPATH)}assert.h
@@ -3888,6 +4032,7 @@ dir.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 dir.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 dir.$(OBJEXT): {$(VPATH)}builtin.h
 dir.$(OBJEXT): {$(VPATH)}config.h
+dir.$(OBJEXT): {$(VPATH)}constant.h
 dir.$(OBJEXT): {$(VPATH)}defines.h
 dir.$(OBJEXT): {$(VPATH)}dir.c
 dir.$(OBJEXT): {$(VPATH)}dir.rbinc
@@ -4050,6 +4195,7 @@ dir.$(OBJEXT): {$(VPATH)}io.h
 dir.$(OBJEXT): {$(VPATH)}missing.h
 dir.$(OBJEXT): {$(VPATH)}onigmo.h
 dir.$(OBJEXT): {$(VPATH)}oniguruma.h
+dir.$(OBJEXT): {$(VPATH)}shape.h
 dir.$(OBJEXT): {$(VPATH)}st.h
 dir.$(OBJEXT): {$(VPATH)}subst.h
 dir.$(OBJEXT): {$(VPATH)}thread.h
@@ -5367,6 +5513,7 @@ encoding.$(OBJEXT): $(top_srcdir)/internal/class.h
 encoding.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 encoding.$(OBJEXT): $(top_srcdir)/internal/enc.h
 encoding.$(OBJEXT): $(top_srcdir)/internal/encoding.h
+encoding.$(OBJEXT): $(top_srcdir)/internal/error.h
 encoding.$(OBJEXT): $(top_srcdir)/internal/gc.h
 encoding.$(OBJEXT): $(top_srcdir)/internal/inits.h
 encoding.$(OBJEXT): $(top_srcdir)/internal/load.h
@@ -5374,6 +5521,7 @@ encoding.$(OBJEXT): $(top_srcdir)/internal/object.h
 encoding.$(OBJEXT): $(top_srcdir)/internal/serial.h
 encoding.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 encoding.$(OBJEXT): $(top_srcdir)/internal/string.h
+encoding.$(OBJEXT): $(top_srcdir)/internal/variable.h
 encoding.$(OBJEXT): $(top_srcdir)/internal/vm.h
 encoding.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 encoding.$(OBJEXT): {$(VPATH)}assert.h
@@ -5387,6 +5535,7 @@ encoding.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 encoding.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 encoding.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 encoding.$(OBJEXT): {$(VPATH)}config.h
+encoding.$(OBJEXT): {$(VPATH)}constant.h
 encoding.$(OBJEXT): {$(VPATH)}debug_counter.h
 encoding.$(OBJEXT): {$(VPATH)}defines.h
 encoding.$(OBJEXT): {$(VPATH)}encindex.h
@@ -5549,6 +5698,7 @@ encoding.$(OBJEXT): {$(VPATH)}onigmo.h
 encoding.$(OBJEXT): {$(VPATH)}oniguruma.h
 encoding.$(OBJEXT): {$(VPATH)}regenc.h
 encoding.$(OBJEXT): {$(VPATH)}ruby_assert.h
+encoding.$(OBJEXT): {$(VPATH)}shape.h
 encoding.$(OBJEXT): {$(VPATH)}st.h
 encoding.$(OBJEXT): {$(VPATH)}subst.h
 encoding.$(OBJEXT): {$(VPATH)}util.h
@@ -5556,6 +5706,7 @@ encoding.$(OBJEXT): {$(VPATH)}vm_debug.h
 encoding.$(OBJEXT): {$(VPATH)}vm_sync.h
 enum.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 enum.$(OBJEXT): $(top_srcdir)/internal/array.h
+enum.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 enum.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 enum.$(OBJEXT): $(top_srcdir)/internal/bits.h
 enum.$(OBJEXT): $(top_srcdir)/internal/class.h
@@ -5573,6 +5724,7 @@ enum.$(OBJEXT): $(top_srcdir)/internal/rational.h
 enum.$(OBJEXT): $(top_srcdir)/internal/re.h
 enum.$(OBJEXT): $(top_srcdir)/internal/serial.h
 enum.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
+enum.$(OBJEXT): $(top_srcdir)/internal/variable.h
 enum.$(OBJEXT): $(top_srcdir)/internal/vm.h
 enum.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 enum.$(OBJEXT): {$(VPATH)}assert.h
@@ -5586,6 +5738,7 @@ enum.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 enum.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 enum.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 enum.$(OBJEXT): {$(VPATH)}config.h
+enum.$(OBJEXT): {$(VPATH)}constant.h
 enum.$(OBJEXT): {$(VPATH)}defines.h
 enum.$(OBJEXT): {$(VPATH)}encoding.h
 enum.$(OBJEXT): {$(VPATH)}enum.c
@@ -5746,14 +5899,21 @@ enum.$(OBJEXT): {$(VPATH)}missing.h
 enum.$(OBJEXT): {$(VPATH)}onigmo.h
 enum.$(OBJEXT): {$(VPATH)}oniguruma.h
 enum.$(OBJEXT): {$(VPATH)}ruby_assert.h
+enum.$(OBJEXT): {$(VPATH)}shape.h
 enum.$(OBJEXT): {$(VPATH)}st.h
 enum.$(OBJEXT): {$(VPATH)}subst.h
 enum.$(OBJEXT): {$(VPATH)}symbol.h
 enum.$(OBJEXT): {$(VPATH)}util.h
+enumerator.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h
+enumerator.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h
+enumerator.$(OBJEXT): $(CCAN_DIR)/list/list.h
+enumerator.$(OBJEXT): $(CCAN_DIR)/str/str.h
 enumerator.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 enumerator.$(OBJEXT): $(top_srcdir)/internal/array.h
+enumerator.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 enumerator.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 enumerator.$(OBJEXT): $(top_srcdir)/internal/bits.h
+enumerator.$(OBJEXT): $(top_srcdir)/internal/class.h
 enumerator.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 enumerator.$(OBJEXT): $(top_srcdir)/internal/enumerator.h
 enumerator.$(OBJEXT): $(top_srcdir)/internal/error.h
@@ -5771,6 +5931,7 @@ enumerator.$(OBJEXT): $(top_srcdir)/internal/struct.h
 enumerator.$(OBJEXT): $(top_srcdir)/internal/vm.h
 enumerator.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 enumerator.$(OBJEXT): {$(VPATH)}assert.h
+enumerator.$(OBJEXT): {$(VPATH)}atomic.h
 enumerator.$(OBJEXT): {$(VPATH)}backward/2/assume.h
 enumerator.$(OBJEXT): {$(VPATH)}backward/2/attributes.h
 enumerator.$(OBJEXT): {$(VPATH)}backward/2/bool.h
@@ -5785,6 +5946,7 @@ enumerator.$(OBJEXT): {$(VPATH)}defines.h
 enumerator.$(OBJEXT): {$(VPATH)}encoding.h
 enumerator.$(OBJEXT): {$(VPATH)}enumerator.c
 enumerator.$(OBJEXT): {$(VPATH)}id.h
+enumerator.$(OBJEXT): {$(VPATH)}id_table.h
 enumerator.$(OBJEXT): {$(VPATH)}intern.h
 enumerator.$(OBJEXT): {$(VPATH)}internal.h
 enumerator.$(OBJEXT): {$(VPATH)}internal/abi.h
@@ -5936,18 +6098,27 @@ enumerator.$(OBJEXT): {$(VPATH)}internal/value_type.h
 enumerator.$(OBJEXT): {$(VPATH)}internal/variable.h
 enumerator.$(OBJEXT): {$(VPATH)}internal/warning_push.h
 enumerator.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
+enumerator.$(OBJEXT): {$(VPATH)}method.h
 enumerator.$(OBJEXT): {$(VPATH)}missing.h
+enumerator.$(OBJEXT): {$(VPATH)}node.h
 enumerator.$(OBJEXT): {$(VPATH)}onigmo.h
 enumerator.$(OBJEXT): {$(VPATH)}oniguruma.h
 enumerator.$(OBJEXT): {$(VPATH)}ruby_assert.h
+enumerator.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+enumerator.$(OBJEXT): {$(VPATH)}shape.h
 enumerator.$(OBJEXT): {$(VPATH)}st.h
 enumerator.$(OBJEXT): {$(VPATH)}subst.h
+enumerator.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
+enumerator.$(OBJEXT): {$(VPATH)}thread_native.h
+enumerator.$(OBJEXT): {$(VPATH)}vm_core.h
+enumerator.$(OBJEXT): {$(VPATH)}vm_opts.h
 error.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h
 error.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h
 error.$(OBJEXT): $(CCAN_DIR)/list/list.h
 error.$(OBJEXT): $(CCAN_DIR)/str/str.h
 error.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 error.$(OBJEXT): $(top_srcdir)/internal/array.h
+error.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 error.$(OBJEXT): $(top_srcdir)/internal/class.h
 error.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 error.$(OBJEXT): $(top_srcdir)/internal/error.h
@@ -5980,7 +6151,6 @@ error.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 error.$(OBJEXT): {$(VPATH)}builtin.h
 error.$(OBJEXT): {$(VPATH)}config.h
 error.$(OBJEXT): {$(VPATH)}constant.h
-error.$(OBJEXT): {$(VPATH)}darray.h
 error.$(OBJEXT): {$(VPATH)}defines.h
 error.$(OBJEXT): {$(VPATH)}encoding.h
 error.$(OBJEXT): {$(VPATH)}error.c
@@ -6146,6 +6316,7 @@ error.$(OBJEXT): {$(VPATH)}onigmo.h
 error.$(OBJEXT): {$(VPATH)}oniguruma.h
 error.$(OBJEXT): {$(VPATH)}ruby_assert.h
 error.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+error.$(OBJEXT): {$(VPATH)}shape.h
 error.$(OBJEXT): {$(VPATH)}st.h
 error.$(OBJEXT): {$(VPATH)}subst.h
 error.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -6160,8 +6331,10 @@ eval.$(OBJEXT): $(CCAN_DIR)/str/str.h
 eval.$(OBJEXT): $(hdrdir)/ruby.h
 eval.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 eval.$(OBJEXT): $(top_srcdir)/internal/array.h
+eval.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 eval.$(OBJEXT): $(top_srcdir)/internal/class.h
 eval.$(OBJEXT): $(top_srcdir)/internal/compilers.h
+eval.$(OBJEXT): $(top_srcdir)/internal/cont.h
 eval.$(OBJEXT): $(top_srcdir)/internal/error.h
 eval.$(OBJEXT): $(top_srcdir)/internal/eval.h
 eval.$(OBJEXT): $(top_srcdir)/internal/gc.h
@@ -6190,7 +6363,6 @@ eval.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 eval.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 eval.$(OBJEXT): {$(VPATH)}config.h
 eval.$(OBJEXT): {$(VPATH)}constant.h
-eval.$(OBJEXT): {$(VPATH)}darray.h
 eval.$(OBJEXT): {$(VPATH)}debug_counter.h
 eval.$(OBJEXT): {$(VPATH)}defines.h
 eval.$(OBJEXT): {$(VPATH)}encoding.h
@@ -6368,6 +6540,7 @@ eval.$(OBJEXT): {$(VPATH)}ractor.h
 eval.$(OBJEXT): {$(VPATH)}ractor_core.h
 eval.$(OBJEXT): {$(VPATH)}ruby_assert.h
 eval.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+eval.$(OBJEXT): {$(VPATH)}shape.h
 eval.$(OBJEXT): {$(VPATH)}st.h
 eval.$(OBJEXT): {$(VPATH)}subst.h
 eval.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -6376,7 +6549,6 @@ eval.$(OBJEXT): {$(VPATH)}vm.h
 eval.$(OBJEXT): {$(VPATH)}vm_core.h
 eval.$(OBJEXT): {$(VPATH)}vm_debug.h
 eval.$(OBJEXT): {$(VPATH)}vm_opts.h
-eval.$(OBJEXT): {$(VPATH)}yjit.h
 explicit_bzero.$(OBJEXT): {$(VPATH)}config.h
 explicit_bzero.$(OBJEXT): {$(VPATH)}explicit_bzero.c
 explicit_bzero.$(OBJEXT): {$(VPATH)}internal/attr/format.h
@@ -6409,6 +6581,7 @@ file.$(OBJEXT): $(top_srcdir)/internal/serial.h
 file.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 file.$(OBJEXT): $(top_srcdir)/internal/string.h
 file.$(OBJEXT): $(top_srcdir)/internal/thread.h
+file.$(OBJEXT): $(top_srcdir)/internal/variable.h
 file.$(OBJEXT): $(top_srcdir)/internal/vm.h
 file.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 file.$(OBJEXT): {$(VPATH)}assert.h
@@ -6422,6 +6595,7 @@ file.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 file.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 file.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 file.$(OBJEXT): {$(VPATH)}config.h
+file.$(OBJEXT): {$(VPATH)}constant.h
 file.$(OBJEXT): {$(VPATH)}defines.h
 file.$(OBJEXT): {$(VPATH)}dln.h
 file.$(OBJEXT): {$(VPATH)}encindex.h
@@ -6584,6 +6758,7 @@ file.$(OBJEXT): {$(VPATH)}io.h
 file.$(OBJEXT): {$(VPATH)}missing.h
 file.$(OBJEXT): {$(VPATH)}onigmo.h
 file.$(OBJEXT): {$(VPATH)}oniguruma.h
+file.$(OBJEXT): {$(VPATH)}shape.h
 file.$(OBJEXT): {$(VPATH)}st.h
 file.$(OBJEXT): {$(VPATH)}subst.h
 file.$(OBJEXT): {$(VPATH)}thread.h
@@ -6595,6 +6770,7 @@ gc.$(OBJEXT): $(CCAN_DIR)/str/str.h
 gc.$(OBJEXT): $(hdrdir)/ruby.h
 gc.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 gc.$(OBJEXT): $(top_srcdir)/internal/array.h
+gc.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 gc.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 gc.$(OBJEXT): $(top_srcdir)/internal/bits.h
 gc.$(OBJEXT): $(top_srcdir)/internal/class.h
@@ -6636,7 +6812,6 @@ gc.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 gc.$(OBJEXT): {$(VPATH)}builtin.h
 gc.$(OBJEXT): {$(VPATH)}config.h
 gc.$(OBJEXT): {$(VPATH)}constant.h
-gc.$(OBJEXT): {$(VPATH)}darray.h
 gc.$(OBJEXT): {$(VPATH)}debug.h
 gc.$(OBJEXT): {$(VPATH)}debug_counter.h
 gc.$(OBJEXT): {$(VPATH)}defines.h
@@ -6644,7 +6819,6 @@ gc.$(OBJEXT): {$(VPATH)}encoding.h
 gc.$(OBJEXT): {$(VPATH)}eval_intern.h
 gc.$(OBJEXT): {$(VPATH)}gc.c
 gc.$(OBJEXT): {$(VPATH)}gc.h
-gc.$(OBJEXT): {$(VPATH)}gc.rb
 gc.$(OBJEXT): {$(VPATH)}gc.rbinc
 gc.$(OBJEXT): {$(VPATH)}id.h
 gc.$(OBJEXT): {$(VPATH)}id_table.h
@@ -6801,6 +6975,7 @@ gc.$(OBJEXT): {$(VPATH)}internal/variable.h
 gc.$(OBJEXT): {$(VPATH)}internal/warning_push.h
 gc.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
 gc.$(OBJEXT): {$(VPATH)}io.h
+gc.$(OBJEXT): {$(VPATH)}iseq.h
 gc.$(OBJEXT): {$(VPATH)}method.h
 gc.$(OBJEXT): {$(VPATH)}missing.h
 gc.$(OBJEXT): {$(VPATH)}mjit.h
@@ -6817,6 +6992,7 @@ gc.$(OBJEXT): {$(VPATH)}regex.h
 gc.$(OBJEXT): {$(VPATH)}regint.h
 gc.$(OBJEXT): {$(VPATH)}ruby_assert.h
 gc.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+gc.$(OBJEXT): {$(VPATH)}shape.h
 gc.$(OBJEXT): {$(VPATH)}st.h
 gc.$(OBJEXT): {$(VPATH)}subst.h
 gc.$(OBJEXT): {$(VPATH)}symbol.h
@@ -6830,7 +7006,6 @@ gc.$(OBJEXT): {$(VPATH)}vm_core.h
 gc.$(OBJEXT): {$(VPATH)}vm_debug.h
 gc.$(OBJEXT): {$(VPATH)}vm_opts.h
 gc.$(OBJEXT): {$(VPATH)}vm_sync.h
-gc.$(OBJEXT): {$(VPATH)}yjit.h
 goruby.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h
 goruby.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h
 goruby.$(OBJEXT): $(CCAN_DIR)/list/list.h
@@ -6838,11 +7013,13 @@ goruby.$(OBJEXT): $(CCAN_DIR)/str/str.h
 goruby.$(OBJEXT): $(hdrdir)/ruby.h
 goruby.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 goruby.$(OBJEXT): $(top_srcdir)/internal/array.h
+goruby.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 goruby.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 goruby.$(OBJEXT): $(top_srcdir)/internal/gc.h
 goruby.$(OBJEXT): $(top_srcdir)/internal/imemo.h
 goruby.$(OBJEXT): $(top_srcdir)/internal/serial.h
 goruby.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
+goruby.$(OBJEXT): $(top_srcdir)/internal/variable.h
 goruby.$(OBJEXT): $(top_srcdir)/internal/vm.h
 goruby.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 goruby.$(OBJEXT): {$(VPATH)}assert.h
@@ -6858,12 +7035,12 @@ goruby.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 goruby.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 goruby.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 goruby.$(OBJEXT): {$(VPATH)}config.h
-goruby.$(OBJEXT): {$(VPATH)}darray.h
+goruby.$(OBJEXT): {$(VPATH)}constant.h
 goruby.$(OBJEXT): {$(VPATH)}defines.h
 goruby.$(OBJEXT): {$(VPATH)}golf_prelude.c
-goruby.$(OBJEXT): {$(VPATH)}golf_prelude.rb
 goruby.$(OBJEXT): {$(VPATH)}goruby.c
 goruby.$(OBJEXT): {$(VPATH)}id.h
+goruby.$(OBJEXT): {$(VPATH)}id_table.h
 goruby.$(OBJEXT): {$(VPATH)}intern.h
 goruby.$(OBJEXT): {$(VPATH)}internal.h
 goruby.$(OBJEXT): {$(VPATH)}internal/abi.h
@@ -6903,6 +7080,7 @@ goruby.$(OBJEXT): {$(VPATH)}internal/attr/nodiscard.h
 goruby.$(OBJEXT): {$(VPATH)}internal/attr/noexcept.h
 goruby.$(OBJEXT): {$(VPATH)}internal/attr/noinline.h
 goruby.$(OBJEXT): {$(VPATH)}internal/attr/nonnull.h
+goruby.$(OBJEXT): {$(VPATH)}internal/attr/nonstring.h
 goruby.$(OBJEXT): {$(VPATH)}internal/attr/noreturn.h
 goruby.$(OBJEXT): {$(VPATH)}internal/attr/pure.h
 goruby.$(OBJEXT): {$(VPATH)}internal/attr/restrict.h
@@ -7013,6 +7191,7 @@ goruby.$(OBJEXT): {$(VPATH)}missing.h
 goruby.$(OBJEXT): {$(VPATH)}node.h
 goruby.$(OBJEXT): {$(VPATH)}ruby_assert.h
 goruby.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+goruby.$(OBJEXT): {$(VPATH)}shape.h
 goruby.$(OBJEXT): {$(VPATH)}st.h
 goruby.$(OBJEXT): {$(VPATH)}subst.h
 goruby.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -7020,8 +7199,13 @@ goruby.$(OBJEXT): {$(VPATH)}thread_native.h
 goruby.$(OBJEXT): {$(VPATH)}vm_core.h
 goruby.$(OBJEXT): {$(VPATH)}vm_debug.h
 goruby.$(OBJEXT): {$(VPATH)}vm_opts.h
+hash.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h
+hash.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h
+hash.$(OBJEXT): $(CCAN_DIR)/list/list.h
+hash.$(OBJEXT): $(CCAN_DIR)/str/str.h
 hash.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 hash.$(OBJEXT): $(top_srcdir)/internal/array.h
+hash.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 hash.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 hash.$(OBJEXT): $(top_srcdir)/internal/bits.h
 hash.$(OBJEXT): $(top_srcdir)/internal/class.h
@@ -7030,16 +7214,20 @@ hash.$(OBJEXT): $(top_srcdir)/internal/cont.h
 hash.$(OBJEXT): $(top_srcdir)/internal/error.h
 hash.$(OBJEXT): $(top_srcdir)/internal/gc.h
 hash.$(OBJEXT): $(top_srcdir)/internal/hash.h
+hash.$(OBJEXT): $(top_srcdir)/internal/imemo.h
 hash.$(OBJEXT): $(top_srcdir)/internal/object.h
 hash.$(OBJEXT): $(top_srcdir)/internal/proc.h
 hash.$(OBJEXT): $(top_srcdir)/internal/serial.h
 hash.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 hash.$(OBJEXT): $(top_srcdir)/internal/string.h
 hash.$(OBJEXT): $(top_srcdir)/internal/symbol.h
+hash.$(OBJEXT): $(top_srcdir)/internal/thread.h
 hash.$(OBJEXT): $(top_srcdir)/internal/time.h
+hash.$(OBJEXT): $(top_srcdir)/internal/variable.h
 hash.$(OBJEXT): $(top_srcdir)/internal/vm.h
 hash.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 hash.$(OBJEXT): {$(VPATH)}assert.h
+hash.$(OBJEXT): {$(VPATH)}atomic.h
 hash.$(OBJEXT): {$(VPATH)}backward/2/assume.h
 hash.$(OBJEXT): {$(VPATH)}backward/2/attributes.h
 hash.$(OBJEXT): {$(VPATH)}backward/2/bool.h
@@ -7050,6 +7238,7 @@ hash.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 hash.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 hash.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 hash.$(OBJEXT): {$(VPATH)}config.h
+hash.$(OBJEXT): {$(VPATH)}constant.h
 hash.$(OBJEXT): {$(VPATH)}debug_counter.h
 hash.$(OBJEXT): {$(VPATH)}defines.h
 hash.$(OBJEXT): {$(VPATH)}encoding.h
@@ -7207,20 +7396,28 @@ hash.$(OBJEXT): {$(VPATH)}internal/value_type.h
 hash.$(OBJEXT): {$(VPATH)}internal/variable.h
 hash.$(OBJEXT): {$(VPATH)}internal/warning_push.h
 hash.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
+hash.$(OBJEXT): {$(VPATH)}iseq.h
+hash.$(OBJEXT): {$(VPATH)}method.h
 hash.$(OBJEXT): {$(VPATH)}missing.h
+hash.$(OBJEXT): {$(VPATH)}node.h
 hash.$(OBJEXT): {$(VPATH)}onigmo.h
 hash.$(OBJEXT): {$(VPATH)}oniguruma.h
 hash.$(OBJEXT): {$(VPATH)}probes.dmyh
 hash.$(OBJEXT): {$(VPATH)}probes.h
 hash.$(OBJEXT): {$(VPATH)}ractor.h
 hash.$(OBJEXT): {$(VPATH)}ruby_assert.h
+hash.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+hash.$(OBJEXT): {$(VPATH)}shape.h
 hash.$(OBJEXT): {$(VPATH)}st.h
 hash.$(OBJEXT): {$(VPATH)}subst.h
 hash.$(OBJEXT): {$(VPATH)}symbol.h
+hash.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
 hash.$(OBJEXT): {$(VPATH)}thread_native.h
 hash.$(OBJEXT): {$(VPATH)}transient_heap.h
 hash.$(OBJEXT): {$(VPATH)}util.h
+hash.$(OBJEXT): {$(VPATH)}vm_core.h
 hash.$(OBJEXT): {$(VPATH)}vm_debug.h
+hash.$(OBJEXT): {$(VPATH)}vm_opts.h
 hash.$(OBJEXT): {$(VPATH)}vm_sync.h
 inits.$(OBJEXT): $(hdrdir)/ruby.h
 inits.$(OBJEXT): $(hdrdir)/ruby/ruby.h
@@ -7392,6 +7589,7 @@ io.$(OBJEXT): $(CCAN_DIR)/list/list.h
 io.$(OBJEXT): $(CCAN_DIR)/str/str.h
 io.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 io.$(OBJEXT): $(top_srcdir)/internal/array.h
+io.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 io.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 io.$(OBJEXT): $(top_srcdir)/internal/bits.h
 io.$(OBJEXT): $(top_srcdir)/internal/class.h
@@ -7428,7 +7626,6 @@ io.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 io.$(OBJEXT): {$(VPATH)}builtin.h
 io.$(OBJEXT): {$(VPATH)}config.h
 io.$(OBJEXT): {$(VPATH)}constant.h
-io.$(OBJEXT): {$(VPATH)}darray.h
 io.$(OBJEXT): {$(VPATH)}defines.h
 io.$(OBJEXT): {$(VPATH)}dln.h
 io.$(OBJEXT): {$(VPATH)}encindex.h
@@ -7599,6 +7796,7 @@ io.$(OBJEXT): {$(VPATH)}oniguruma.h
 io.$(OBJEXT): {$(VPATH)}ractor.h
 io.$(OBJEXT): {$(VPATH)}ruby_assert.h
 io.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+io.$(OBJEXT): {$(VPATH)}shape.h
 io.$(OBJEXT): {$(VPATH)}st.h
 io.$(OBJEXT): {$(VPATH)}subst.h
 io.$(OBJEXT): {$(VPATH)}thread.h
@@ -7608,11 +7806,18 @@ io.$(OBJEXT): {$(VPATH)}util.h
 io.$(OBJEXT): {$(VPATH)}vm_core.h
 io.$(OBJEXT): {$(VPATH)}vm_opts.h
 io_buffer.$(OBJEXT): $(hdrdir)/ruby/ruby.h
+io_buffer.$(OBJEXT): $(top_srcdir)/internal/array.h
+io_buffer.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 io_buffer.$(OBJEXT): $(top_srcdir)/internal/bits.h
 io_buffer.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 io_buffer.$(OBJEXT): $(top_srcdir)/internal/error.h
+io_buffer.$(OBJEXT): $(top_srcdir)/internal/fixnum.h
+io_buffer.$(OBJEXT): $(top_srcdir)/internal/numeric.h
+io_buffer.$(OBJEXT): $(top_srcdir)/internal/serial.h
 io_buffer.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 io_buffer.$(OBJEXT): $(top_srcdir)/internal/string.h
+io_buffer.$(OBJEXT): $(top_srcdir)/internal/thread.h
+io_buffer.$(OBJEXT): $(top_srcdir)/internal/vm.h
 io_buffer.$(OBJEXT): {$(VPATH)}assert.h
 io_buffer.$(OBJEXT): {$(VPATH)}backward/2/assume.h
 io_buffer.$(OBJEXT): {$(VPATH)}backward/2/attributes.h
@@ -7793,6 +7998,7 @@ iseq.$(OBJEXT): $(CCAN_DIR)/str/str.h
 iseq.$(OBJEXT): $(hdrdir)/ruby.h
 iseq.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 iseq.$(OBJEXT): $(top_srcdir)/internal/array.h
+iseq.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 iseq.$(OBJEXT): $(top_srcdir)/internal/bits.h
 iseq.$(OBJEXT): $(top_srcdir)/internal/class.h
 iseq.$(OBJEXT): $(top_srcdir)/internal/compile.h
@@ -7826,7 +8032,6 @@ iseq.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 iseq.$(OBJEXT): {$(VPATH)}builtin.h
 iseq.$(OBJEXT): {$(VPATH)}config.h
 iseq.$(OBJEXT): {$(VPATH)}constant.h
-iseq.$(OBJEXT): {$(VPATH)}darray.h
 iseq.$(OBJEXT): {$(VPATH)}debug_counter.h
 iseq.$(OBJEXT): {$(VPATH)}defines.h
 iseq.$(OBJEXT): {$(VPATH)}encoding.h
@@ -8000,6 +8205,7 @@ iseq.$(OBJEXT): {$(VPATH)}oniguruma.h
 iseq.$(OBJEXT): {$(VPATH)}ractor.h
 iseq.$(OBJEXT): {$(VPATH)}ruby_assert.h
 iseq.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+iseq.$(OBJEXT): {$(VPATH)}shape.h
 iseq.$(OBJEXT): {$(VPATH)}st.h
 iseq.$(OBJEXT): {$(VPATH)}subst.h
 iseq.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -8015,6 +8221,7 @@ load.$(OBJEXT): $(CCAN_DIR)/list/list.h
 load.$(OBJEXT): $(CCAN_DIR)/str/str.h
 load.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 load.$(OBJEXT): $(top_srcdir)/internal/array.h
+load.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 load.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 load.$(OBJEXT): $(top_srcdir)/internal/dir.h
 load.$(OBJEXT): $(top_srcdir)/internal/error.h
@@ -8212,6 +8419,7 @@ load.$(OBJEXT): {$(VPATH)}probes.dmyh
 load.$(OBJEXT): {$(VPATH)}probes.h
 load.$(OBJEXT): {$(VPATH)}ruby_assert.h
 load.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+load.$(OBJEXT): {$(VPATH)}shape.h
 load.$(OBJEXT): {$(VPATH)}st.h
 load.$(OBJEXT): {$(VPATH)}subst.h
 load.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -8710,15 +8918,24 @@ main.$(OBJEXT): {$(VPATH)}missing.h
 main.$(OBJEXT): {$(VPATH)}st.h
 main.$(OBJEXT): {$(VPATH)}subst.h
 main.$(OBJEXT): {$(VPATH)}vm_debug.h
+marshal.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h
+marshal.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h
+marshal.$(OBJEXT): $(CCAN_DIR)/list/list.h
+marshal.$(OBJEXT): $(CCAN_DIR)/str/str.h
 marshal.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 marshal.$(OBJEXT): $(top_srcdir)/internal/array.h
+marshal.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 marshal.$(OBJEXT): $(top_srcdir)/internal/bignum.h
+marshal.$(OBJEXT): $(top_srcdir)/internal/bits.h
 marshal.$(OBJEXT): $(top_srcdir)/internal/class.h
 marshal.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 marshal.$(OBJEXT): $(top_srcdir)/internal/encoding.h
 marshal.$(OBJEXT): $(top_srcdir)/internal/error.h
+marshal.$(OBJEXT): $(top_srcdir)/internal/fixnum.h
 marshal.$(OBJEXT): $(top_srcdir)/internal/gc.h
 marshal.$(OBJEXT): $(top_srcdir)/internal/hash.h
+marshal.$(OBJEXT): $(top_srcdir)/internal/imemo.h
+marshal.$(OBJEXT): $(top_srcdir)/internal/numeric.h
 marshal.$(OBJEXT): $(top_srcdir)/internal/object.h
 marshal.$(OBJEXT): $(top_srcdir)/internal/serial.h
 marshal.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
@@ -8726,9 +8943,11 @@ marshal.$(OBJEXT): $(top_srcdir)/internal/string.h
 marshal.$(OBJEXT): $(top_srcdir)/internal/struct.h
 marshal.$(OBJEXT): $(top_srcdir)/internal/symbol.h
 marshal.$(OBJEXT): $(top_srcdir)/internal/util.h
+marshal.$(OBJEXT): $(top_srcdir)/internal/variable.h
 marshal.$(OBJEXT): $(top_srcdir)/internal/vm.h
 marshal.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 marshal.$(OBJEXT): {$(VPATH)}assert.h
+marshal.$(OBJEXT): {$(VPATH)}atomic.h
 marshal.$(OBJEXT): {$(VPATH)}backward/2/assume.h
 marshal.$(OBJEXT): {$(VPATH)}backward/2/attributes.h
 marshal.$(OBJEXT): {$(VPATH)}backward/2/bool.h
@@ -8740,9 +8959,11 @@ marshal.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 marshal.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 marshal.$(OBJEXT): {$(VPATH)}builtin.h
 marshal.$(OBJEXT): {$(VPATH)}config.h
+marshal.$(OBJEXT): {$(VPATH)}constant.h
 marshal.$(OBJEXT): {$(VPATH)}defines.h
 marshal.$(OBJEXT): {$(VPATH)}encindex.h
 marshal.$(OBJEXT): {$(VPATH)}encoding.h
+marshal.$(OBJEXT): {$(VPATH)}id.h
 marshal.$(OBJEXT): {$(VPATH)}id_table.h
 marshal.$(OBJEXT): {$(VPATH)}intern.h
 marshal.$(OBJEXT): {$(VPATH)}internal.h
@@ -8783,6 +9004,7 @@ marshal.$(OBJEXT): {$(VPATH)}internal/attr/nodiscard.h
 marshal.$(OBJEXT): {$(VPATH)}internal/attr/noexcept.h
 marshal.$(OBJEXT): {$(VPATH)}internal/attr/noinline.h
 marshal.$(OBJEXT): {$(VPATH)}internal/attr/nonnull.h
+marshal.$(OBJEXT): {$(VPATH)}internal/attr/nonstring.h
 marshal.$(OBJEXT): {$(VPATH)}internal/attr/noreturn.h
 marshal.$(OBJEXT): {$(VPATH)}internal/attr/pure.h
 marshal.$(OBJEXT): {$(VPATH)}internal/attr/restrict.h
@@ -8898,12 +9120,21 @@ marshal.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
 marshal.$(OBJEXT): {$(VPATH)}io.h
 marshal.$(OBJEXT): {$(VPATH)}marshal.c
 marshal.$(OBJEXT): {$(VPATH)}marshal.rbinc
+marshal.$(OBJEXT): {$(VPATH)}method.h
 marshal.$(OBJEXT): {$(VPATH)}missing.h
+marshal.$(OBJEXT): {$(VPATH)}node.h
 marshal.$(OBJEXT): {$(VPATH)}onigmo.h
 marshal.$(OBJEXT): {$(VPATH)}oniguruma.h
+marshal.$(OBJEXT): {$(VPATH)}ruby_assert.h
+marshal.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+marshal.$(OBJEXT): {$(VPATH)}shape.h
 marshal.$(OBJEXT): {$(VPATH)}st.h
 marshal.$(OBJEXT): {$(VPATH)}subst.h
+marshal.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
+marshal.$(OBJEXT): {$(VPATH)}thread_native.h
 marshal.$(OBJEXT): {$(VPATH)}util.h
+marshal.$(OBJEXT): {$(VPATH)}vm_core.h
+marshal.$(OBJEXT): {$(VPATH)}vm_opts.h
 math.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 math.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 math.$(OBJEXT): $(top_srcdir)/internal/class.h
@@ -8914,6 +9145,7 @@ math.$(OBJEXT): $(top_srcdir)/internal/math.h
 math.$(OBJEXT): $(top_srcdir)/internal/object.h
 math.$(OBJEXT): $(top_srcdir)/internal/serial.h
 math.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
+math.$(OBJEXT): $(top_srcdir)/internal/variable.h
 math.$(OBJEXT): $(top_srcdir)/internal/vm.h
 math.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 math.$(OBJEXT): {$(VPATH)}assert.h
@@ -8927,6 +9159,7 @@ math.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 math.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 math.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 math.$(OBJEXT): {$(VPATH)}config.h
+math.$(OBJEXT): {$(VPATH)}constant.h
 math.$(OBJEXT): {$(VPATH)}defines.h
 math.$(OBJEXT): {$(VPATH)}id_table.h
 math.$(OBJEXT): {$(VPATH)}intern.h
@@ -9073,15 +9306,20 @@ math.$(OBJEXT): {$(VPATH)}internal/warning_push.h
 math.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
 math.$(OBJEXT): {$(VPATH)}math.c
 math.$(OBJEXT): {$(VPATH)}missing.h
+math.$(OBJEXT): {$(VPATH)}shape.h
 math.$(OBJEXT): {$(VPATH)}st.h
 math.$(OBJEXT): {$(VPATH)}subst.h
 memory_view.$(OBJEXT): $(hdrdir)/ruby/ruby.h
+memory_view.$(OBJEXT): $(top_srcdir)/internal/compilers.h
+memory_view.$(OBJEXT): $(top_srcdir)/internal/gc.h
 memory_view.$(OBJEXT): $(top_srcdir)/internal/hash.h
 memory_view.$(OBJEXT): $(top_srcdir)/internal/variable.h
+memory_view.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 memory_view.$(OBJEXT): {$(VPATH)}assert.h
 memory_view.$(OBJEXT): {$(VPATH)}backward/2/assume.h
 memory_view.$(OBJEXT): {$(VPATH)}backward/2/attributes.h
 memory_view.$(OBJEXT): {$(VPATH)}backward/2/bool.h
+memory_view.$(OBJEXT): {$(VPATH)}backward/2/gcc_version_since.h
 memory_view.$(OBJEXT): {$(VPATH)}backward/2/inttypes.h
 memory_view.$(OBJEXT): {$(VPATH)}backward/2/limits.h
 memory_view.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
@@ -9237,6 +9475,7 @@ memory_view.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
 memory_view.$(OBJEXT): {$(VPATH)}memory_view.c
 memory_view.$(OBJEXT): {$(VPATH)}memory_view.h
 memory_view.$(OBJEXT): {$(VPATH)}missing.h
+memory_view.$(OBJEXT): {$(VPATH)}shape.h
 memory_view.$(OBJEXT): {$(VPATH)}st.h
 memory_view.$(OBJEXT): {$(VPATH)}subst.h
 memory_view.$(OBJEXT): {$(VPATH)}util.h
@@ -9247,12 +9486,15 @@ miniinit.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h
 miniinit.$(OBJEXT): $(CCAN_DIR)/list/list.h
 miniinit.$(OBJEXT): $(CCAN_DIR)/str/str.h
 miniinit.$(OBJEXT): $(hdrdir)/ruby/ruby.h
+miniinit.$(OBJEXT): $(srcdir)/mjit_c.rb
 miniinit.$(OBJEXT): $(top_srcdir)/internal/array.h
+miniinit.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 miniinit.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 miniinit.$(OBJEXT): $(top_srcdir)/internal/gc.h
 miniinit.$(OBJEXT): $(top_srcdir)/internal/imemo.h
 miniinit.$(OBJEXT): $(top_srcdir)/internal/serial.h
 miniinit.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
+miniinit.$(OBJEXT): $(top_srcdir)/internal/variable.h
 miniinit.$(OBJEXT): $(top_srcdir)/internal/vm.h
 miniinit.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 miniinit.$(OBJEXT): {$(VPATH)}array.rb
@@ -9270,13 +9512,14 @@ miniinit.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 miniinit.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 miniinit.$(OBJEXT): {$(VPATH)}builtin.h
 miniinit.$(OBJEXT): {$(VPATH)}config.h
-miniinit.$(OBJEXT): {$(VPATH)}darray.h
+miniinit.$(OBJEXT): {$(VPATH)}constant.h
 miniinit.$(OBJEXT): {$(VPATH)}defines.h
 miniinit.$(OBJEXT): {$(VPATH)}dir.rb
 miniinit.$(OBJEXT): {$(VPATH)}encoding.h
 miniinit.$(OBJEXT): {$(VPATH)}gc.rb
 miniinit.$(OBJEXT): {$(VPATH)}gem_prelude.rb
 miniinit.$(OBJEXT): {$(VPATH)}id.h
+miniinit.$(OBJEXT): {$(VPATH)}id_table.h
 miniinit.$(OBJEXT): {$(VPATH)}intern.h
 miniinit.$(OBJEXT): {$(VPATH)}internal.h
 miniinit.$(OBJEXT): {$(VPATH)}internal/abi.h
@@ -9316,6 +9559,7 @@ miniinit.$(OBJEXT): {$(VPATH)}internal/attr/nodiscard.h
 miniinit.$(OBJEXT): {$(VPATH)}internal/attr/noexcept.h
 miniinit.$(OBJEXT): {$(VPATH)}internal/attr/noinline.h
 miniinit.$(OBJEXT): {$(VPATH)}internal/attr/nonnull.h
+miniinit.$(OBJEXT): {$(VPATH)}internal/attr/nonstring.h
 miniinit.$(OBJEXT): {$(VPATH)}internal/attr/noreturn.h
 miniinit.$(OBJEXT): {$(VPATH)}internal/attr/pure.h
 miniinit.$(OBJEXT): {$(VPATH)}internal/attr/restrict.h
@@ -9437,6 +9681,8 @@ miniinit.$(OBJEXT): {$(VPATH)}mini_builtin.c
 miniinit.$(OBJEXT): {$(VPATH)}miniinit.c
 miniinit.$(OBJEXT): {$(VPATH)}miniprelude.c
 miniinit.$(OBJEXT): {$(VPATH)}missing.h
+miniinit.$(OBJEXT): {$(VPATH)}mjit.rb
+miniinit.$(OBJEXT): {$(VPATH)}mjit_c.rb
 miniinit.$(OBJEXT): {$(VPATH)}nilclass.rb
 miniinit.$(OBJEXT): {$(VPATH)}node.h
 miniinit.$(OBJEXT): {$(VPATH)}numeric.rb
@@ -9447,10 +9693,13 @@ miniinit.$(OBJEXT): {$(VPATH)}prelude.rb
 miniinit.$(OBJEXT): {$(VPATH)}ractor.rb
 miniinit.$(OBJEXT): {$(VPATH)}ruby_assert.h
 miniinit.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+miniinit.$(OBJEXT): {$(VPATH)}shape.h
 miniinit.$(OBJEXT): {$(VPATH)}st.h
 miniinit.$(OBJEXT): {$(VPATH)}subst.h
+miniinit.$(OBJEXT): {$(VPATH)}symbol.rb
 miniinit.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
 miniinit.$(OBJEXT): {$(VPATH)}thread_native.h
+miniinit.$(OBJEXT): {$(VPATH)}thread_sync.rb
 miniinit.$(OBJEXT): {$(VPATH)}timev.rb
 miniinit.$(OBJEXT): {$(VPATH)}trace_point.rb
 miniinit.$(OBJEXT): {$(VPATH)}vm_core.h
@@ -9465,6 +9714,7 @@ mjit.$(OBJEXT): $(hdrdir)/ruby.h
 mjit.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 mjit.$(OBJEXT): $(hdrdir)/ruby/version.h
 mjit.$(OBJEXT): $(top_srcdir)/internal/array.h
+mjit.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 mjit.$(OBJEXT): $(top_srcdir)/internal/class.h
 mjit.$(OBJEXT): $(top_srcdir)/internal/cmdlineopt.h
 mjit.$(OBJEXT): $(top_srcdir)/internal/compile.h
@@ -9474,8 +9724,10 @@ mjit.$(OBJEXT): $(top_srcdir)/internal/file.h
 mjit.$(OBJEXT): $(top_srcdir)/internal/gc.h
 mjit.$(OBJEXT): $(top_srcdir)/internal/hash.h
 mjit.$(OBJEXT): $(top_srcdir)/internal/imemo.h
+mjit.$(OBJEXT): $(top_srcdir)/internal/process.h
 mjit.$(OBJEXT): $(top_srcdir)/internal/serial.h
 mjit.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
+mjit.$(OBJEXT): $(top_srcdir)/internal/variable.h
 mjit.$(OBJEXT): $(top_srcdir)/internal/vm.h
 mjit.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 mjit.$(OBJEXT): {$(VPATH)}assert.h
@@ -9492,7 +9744,6 @@ mjit.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 mjit.$(OBJEXT): {$(VPATH)}builtin.h
 mjit.$(OBJEXT): {$(VPATH)}config.h
 mjit.$(OBJEXT): {$(VPATH)}constant.h
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 mjit.$(OBJEXT): {$(VPATH)}debug.h
 mjit.$(OBJEXT): {$(VPATH)}debug_counter.h
 mjit.$(OBJEXT): {$(VPATH)}defines.h
@@ -9660,13 +9911,17 @@ mjit.$(OBJEXT): {$(VPATH)}method.h
 mjit.$(OBJEXT): {$(VPATH)}missing.h
 mjit.$(OBJEXT): {$(VPATH)}mjit.c
 mjit.$(OBJEXT): {$(VPATH)}mjit.h
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 mjit.$(OBJEXT): {$(VPATH)}mjit_config.h
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 mjit.$(OBJEXT): {$(VPATH)}node.h
 mjit.$(OBJEXT): {$(VPATH)}onigmo.h
 mjit.$(OBJEXT): {$(VPATH)}oniguruma.h
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 mjit.$(OBJEXT): {$(VPATH)}ruby_atomic.h
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 mjit.$(OBJEXT): {$(VPATH)}st.h
 mjit.$(OBJEXT): {$(VPATH)}subst.h
 mjit.$(OBJEXT): {$(VPATH)}thread.h
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+mjit_c.$(OBJEXT): {$(VPATH)}internal/core/rstring.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/core/rstruct.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/core/rtypeddata.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/ctype.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/dllexport.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/dosish.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/error.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/eval.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/event.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/fl_type.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/gc.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/glob.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/globals.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/has/attribute.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/has/builtin.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/has/c_attribute.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/has/cpp_attribute.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/has/declspec_attribute.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/has/extension.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/has/feature.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/has/warning.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/array.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/bignum.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/class.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/compar.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/complex.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/cont.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/dir.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/enum.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/enumerator.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/error.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/eval.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/file.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/gc.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/hash.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/io.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/load.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/marshal.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/numeric.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/object.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/parse.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/proc.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/process.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/random.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/range.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/rational.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/re.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/ruby.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/select.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/select/largesize.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/signal.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/sprintf.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/string.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/struct.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/thread.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/time.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/variable.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/intern/vm.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/interpreter.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/iterator.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/memory.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/method.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/module.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/newobj.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/rgengc.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/scan_args.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/special_consts.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/static_assert.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/stdalign.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/stdbool.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/symbol.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/value.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/value_type.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/variable.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/warning_push.h
+mjit_c.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
+mjit_c.$(OBJEXT): {$(VPATH)}iseq.h
+mjit_c.$(OBJEXT): {$(VPATH)}method.h
+mjit_c.$(OBJEXT): {$(VPATH)}missing.h
+mjit_c.$(OBJEXT): {$(VPATH)}mjit.h
+mjit_c.$(OBJEXT): {$(VPATH)}mjit_c.c
+mjit_c.$(OBJEXT): {$(VPATH)}mjit_c.h
+mjit_c.$(OBJEXT): {$(VPATH)}mjit_c.rb
+mjit_c.$(OBJEXT): {$(VPATH)}mjit_c.rbinc
+mjit_c.$(OBJEXT): {$(VPATH)}mjit_sp_inc.inc
+mjit_c.$(OBJEXT): {$(VPATH)}node.h
+mjit_c.$(OBJEXT): {$(VPATH)}ruby_assert.h
+mjit_c.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+mjit_c.$(OBJEXT): {$(VPATH)}shape.h
+mjit_c.$(OBJEXT): {$(VPATH)}st.h
+mjit_c.$(OBJEXT): {$(VPATH)}subst.h
+mjit_c.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
+mjit_c.$(OBJEXT): {$(VPATH)}thread_native.h
+mjit_c.$(OBJEXT): {$(VPATH)}vm_callinfo.h
+mjit_c.$(OBJEXT): {$(VPATH)}vm_core.h
+mjit_c.$(OBJEXT): {$(VPATH)}vm_exec.h
+mjit_c.$(OBJEXT): {$(VPATH)}vm_insnhelper.h
+mjit_c.$(OBJEXT): {$(VPATH)}vm_opts.h
+mjit_c.$(OBJEXT): {$(VPATH)}yjit.h
 node.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h
 node.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h
 node.$(OBJEXT): $(CCAN_DIR)/list/list.h
 node.$(OBJEXT): $(CCAN_DIR)/str/str.h
 node.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 node.$(OBJEXT): $(top_srcdir)/internal/array.h
+node.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 node.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 node.$(OBJEXT): $(top_srcdir)/internal/gc.h
 node.$(OBJEXT): $(top_srcdir)/internal/hash.h
@@ -9909,7 +10170,6 @@ node.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 node.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 node.$(OBJEXT): {$(VPATH)}config.h
 node.$(OBJEXT): {$(VPATH)}constant.h
-node.$(OBJEXT): {$(VPATH)}darray.h
 node.$(OBJEXT): {$(VPATH)}defines.h
 node.$(OBJEXT): {$(VPATH)}id.h
 node.$(OBJEXT): {$(VPATH)}id_table.h
@@ -10061,6 +10321,7 @@ node.$(OBJEXT): {$(VPATH)}node.c
 node.$(OBJEXT): {$(VPATH)}node.h
 node.$(OBJEXT): {$(VPATH)}ruby_assert.h
 node.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+node.$(OBJEXT): {$(VPATH)}shape.h
 node.$(OBJEXT): {$(VPATH)}st.h
 node.$(OBJEXT): {$(VPATH)}subst.h
 node.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -10258,16 +10519,21 @@ numeric.$(OBJEXT): {$(VPATH)}internal/warning_push.h
 numeric.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
 numeric.$(OBJEXT): {$(VPATH)}missing.h
 numeric.$(OBJEXT): {$(VPATH)}numeric.c
-numeric.$(OBJEXT): {$(VPATH)}numeric.rb
 numeric.$(OBJEXT): {$(VPATH)}numeric.rbinc
 numeric.$(OBJEXT): {$(VPATH)}onigmo.h
 numeric.$(OBJEXT): {$(VPATH)}oniguruma.h
 numeric.$(OBJEXT): {$(VPATH)}ruby_assert.h
+numeric.$(OBJEXT): {$(VPATH)}shape.h
 numeric.$(OBJEXT): {$(VPATH)}st.h
 numeric.$(OBJEXT): {$(VPATH)}subst.h
 numeric.$(OBJEXT): {$(VPATH)}util.h
+object.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h
+object.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h
+object.$(OBJEXT): $(CCAN_DIR)/list/list.h
+object.$(OBJEXT): $(CCAN_DIR)/str/str.h
 object.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 object.$(OBJEXT): $(top_srcdir)/internal/array.h
+object.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 object.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 object.$(OBJEXT): $(top_srcdir)/internal/bits.h
 object.$(OBJEXT): $(top_srcdir)/internal/class.h
@@ -10276,6 +10542,7 @@ object.$(OBJEXT): $(top_srcdir)/internal/error.h
 object.$(OBJEXT): $(top_srcdir)/internal/eval.h
 object.$(OBJEXT): $(top_srcdir)/internal/fixnum.h
 object.$(OBJEXT): $(top_srcdir)/internal/gc.h
+object.$(OBJEXT): $(top_srcdir)/internal/imemo.h
 object.$(OBJEXT): $(top_srcdir)/internal/inits.h
 object.$(OBJEXT): $(top_srcdir)/internal/numeric.h
 object.$(OBJEXT): $(top_srcdir)/internal/object.h
@@ -10288,6 +10555,7 @@ object.$(OBJEXT): $(top_srcdir)/internal/variable.h
 object.$(OBJEXT): $(top_srcdir)/internal/vm.h
 object.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 object.$(OBJEXT): {$(VPATH)}assert.h
+object.$(OBJEXT): {$(VPATH)}atomic.h
 object.$(OBJEXT): {$(VPATH)}backward/2/assume.h
 object.$(OBJEXT): {$(VPATH)}backward/2/attributes.h
 object.$(OBJEXT): {$(VPATH)}backward/2/bool.h
@@ -10455,22 +10723,32 @@ object.$(OBJEXT): {$(VPATH)}internal/value_type.h
 object.$(OBJEXT): {$(VPATH)}internal/variable.h
 object.$(OBJEXT): {$(VPATH)}internal/warning_push.h
 object.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
-object.$(OBJEXT): {$(VPATH)}kernel.rb
 object.$(OBJEXT): {$(VPATH)}kernel.rbinc
+object.$(OBJEXT): {$(VPATH)}method.h
 object.$(OBJEXT): {$(VPATH)}missing.h
 object.$(OBJEXT): {$(VPATH)}nilclass.rbinc
+object.$(OBJEXT): {$(VPATH)}node.h
 object.$(OBJEXT): {$(VPATH)}object.c
 object.$(OBJEXT): {$(VPATH)}onigmo.h
 object.$(OBJEXT): {$(VPATH)}oniguruma.h
 object.$(OBJEXT): {$(VPATH)}probes.dmyh
 object.$(OBJEXT): {$(VPATH)}probes.h
+object.$(OBJEXT): {$(VPATH)}ruby_assert.h
+object.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+object.$(OBJEXT): {$(VPATH)}shape.h
 object.$(OBJEXT): {$(VPATH)}st.h
 object.$(OBJEXT): {$(VPATH)}subst.h
+object.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
+object.$(OBJEXT): {$(VPATH)}thread_native.h
 object.$(OBJEXT): {$(VPATH)}util.h
+object.$(OBJEXT): {$(VPATH)}variable.h
+object.$(OBJEXT): {$(VPATH)}vm_core.h
+object.$(OBJEXT): {$(VPATH)}vm_opts.h
 pack.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 pack.$(OBJEXT): $(top_srcdir)/internal/array.h
 pack.$(OBJEXT): $(top_srcdir)/internal/bits.h
 pack.$(OBJEXT): $(top_srcdir)/internal/compilers.h
+pack.$(OBJEXT): $(top_srcdir)/internal/gc.h
 pack.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 pack.$(OBJEXT): $(top_srcdir)/internal/string.h
 pack.$(OBJEXT): $(top_srcdir)/internal/symbol.h
@@ -10648,6 +10926,7 @@ pack.$(OBJEXT): {$(VPATH)}onigmo.h
 pack.$(OBJEXT): {$(VPATH)}oniguruma.h
 pack.$(OBJEXT): {$(VPATH)}pack.c
 pack.$(OBJEXT): {$(VPATH)}pack.rbinc
+pack.$(OBJEXT): {$(VPATH)}shape.h
 pack.$(OBJEXT): {$(VPATH)}st.h
 pack.$(OBJEXT): {$(VPATH)}subst.h
 pack.$(OBJEXT): {$(VPATH)}util.h
@@ -10659,6 +10938,7 @@ parse.$(OBJEXT): $(top_srcdir)/internal/bits.h
 parse.$(OBJEXT): $(top_srcdir)/internal/compile.h
 parse.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 parse.$(OBJEXT): $(top_srcdir)/internal/complex.h
+parse.$(OBJEXT): $(top_srcdir)/internal/encoding.h
 parse.$(OBJEXT): $(top_srcdir)/internal/error.h
 parse.$(OBJEXT): $(top_srcdir)/internal/fixnum.h
 parse.$(OBJEXT): $(top_srcdir)/internal/gc.h
@@ -10860,6 +11140,7 @@ parse.$(OBJEXT): {$(VPATH)}ractor.h
 parse.$(OBJEXT): {$(VPATH)}regenc.h
 parse.$(OBJEXT): {$(VPATH)}regex.h
 parse.$(OBJEXT): {$(VPATH)}ruby_assert.h
+parse.$(OBJEXT): {$(VPATH)}shape.h
 parse.$(OBJEXT): {$(VPATH)}st.h
 parse.$(OBJEXT): {$(VPATH)}subst.h
 parse.$(OBJEXT): {$(VPATH)}symbol.h
@@ -10870,11 +11151,13 @@ proc.$(OBJEXT): $(CCAN_DIR)/list/list.h
 proc.$(OBJEXT): $(CCAN_DIR)/str/str.h
 proc.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 proc.$(OBJEXT): $(top_srcdir)/internal/array.h
+proc.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 proc.$(OBJEXT): $(top_srcdir)/internal/class.h
 proc.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 proc.$(OBJEXT): $(top_srcdir)/internal/error.h
 proc.$(OBJEXT): $(top_srcdir)/internal/eval.h
 proc.$(OBJEXT): $(top_srcdir)/internal/gc.h
+proc.$(OBJEXT): $(top_srcdir)/internal/hash.h
 proc.$(OBJEXT): $(top_srcdir)/internal/imemo.h
 proc.$(OBJEXT): $(top_srcdir)/internal/object.h
 proc.$(OBJEXT): $(top_srcdir)/internal/proc.h
@@ -10882,6 +11165,7 @@ proc.$(OBJEXT): $(top_srcdir)/internal/serial.h
 proc.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 proc.$(OBJEXT): $(top_srcdir)/internal/string.h
 proc.$(OBJEXT): $(top_srcdir)/internal/symbol.h
+proc.$(OBJEXT): $(top_srcdir)/internal/variable.h
 proc.$(OBJEXT): $(top_srcdir)/internal/vm.h
 proc.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 proc.$(OBJEXT): {$(VPATH)}assert.h
@@ -10896,7 +11180,7 @@ proc.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 proc.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 proc.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 proc.$(OBJEXT): {$(VPATH)}config.h
-proc.$(OBJEXT): {$(VPATH)}darray.h
+proc.$(OBJEXT): {$(VPATH)}constant.h
 proc.$(OBJEXT): {$(VPATH)}defines.h
 proc.$(OBJEXT): {$(VPATH)}encoding.h
 proc.$(OBJEXT): {$(VPATH)}eval_intern.h
@@ -11063,6 +11347,7 @@ proc.$(OBJEXT): {$(VPATH)}oniguruma.h
 proc.$(OBJEXT): {$(VPATH)}proc.c
 proc.$(OBJEXT): {$(VPATH)}ruby_assert.h
 proc.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+proc.$(OBJEXT): {$(VPATH)}shape.h
 proc.$(OBJEXT): {$(VPATH)}st.h
 proc.$(OBJEXT): {$(VPATH)}subst.h
 proc.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -11077,6 +11362,7 @@ process.$(OBJEXT): $(CCAN_DIR)/str/str.h
 process.$(OBJEXT): $(hdrdir)/ruby.h
 process.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 process.$(OBJEXT): $(top_srcdir)/internal/array.h
+process.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 process.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 process.$(OBJEXT): $(top_srcdir)/internal/bits.h
 process.$(OBJEXT): $(top_srcdir)/internal/class.h
@@ -11112,7 +11398,6 @@ process.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 process.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 process.$(OBJEXT): {$(VPATH)}config.h
 process.$(OBJEXT): {$(VPATH)}constant.h
-process.$(OBJEXT): {$(VPATH)}darray.h
 process.$(OBJEXT): {$(VPATH)}debug_counter.h
 process.$(OBJEXT): {$(VPATH)}defines.h
 process.$(OBJEXT): {$(VPATH)}dln.h
@@ -11283,6 +11568,7 @@ process.$(OBJEXT): {$(VPATH)}process.c
 process.$(OBJEXT): {$(VPATH)}ractor.h
 process.$(OBJEXT): {$(VPATH)}ruby_assert.h
 process.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+process.$(OBJEXT): {$(VPATH)}shape.h
 process.$(OBJEXT): {$(VPATH)}st.h
 process.$(OBJEXT): {$(VPATH)}subst.h
 process.$(OBJEXT): {$(VPATH)}thread.h
@@ -11291,13 +11577,14 @@ process.$(OBJEXT): {$(VPATH)}thread_native.h
 process.$(OBJEXT): {$(VPATH)}util.h
 process.$(OBJEXT): {$(VPATH)}vm_core.h
 process.$(OBJEXT): {$(VPATH)}vm_opts.h
-process.$(OBJEXT): {$(VPATH)}yjit.h
 ractor.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h
 ractor.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h
 ractor.$(OBJEXT): $(CCAN_DIR)/list/list.h
 ractor.$(OBJEXT): $(CCAN_DIR)/str/str.h
+ractor.$(OBJEXT): $(hdrdir)/ruby.h
 ractor.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 ractor.$(OBJEXT): $(top_srcdir)/internal/array.h
+ractor.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 ractor.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 ractor.$(OBJEXT): $(top_srcdir)/internal/bits.h
 ractor.$(OBJEXT): $(top_srcdir)/internal/compilers.h
@@ -11314,6 +11601,7 @@ ractor.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 ractor.$(OBJEXT): $(top_srcdir)/internal/string.h
 ractor.$(OBJEXT): $(top_srcdir)/internal/struct.h
 ractor.$(OBJEXT): $(top_srcdir)/internal/thread.h
+ractor.$(OBJEXT): $(top_srcdir)/internal/variable.h
 ractor.$(OBJEXT): $(top_srcdir)/internal/vm.h
 ractor.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 ractor.$(OBJEXT): {$(VPATH)}assert.h
@@ -11329,7 +11617,7 @@ ractor.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 ractor.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 ractor.$(OBJEXT): {$(VPATH)}builtin.h
 ractor.$(OBJEXT): {$(VPATH)}config.h
-ractor.$(OBJEXT): {$(VPATH)}darray.h
+ractor.$(OBJEXT): {$(VPATH)}constant.h
 ractor.$(OBJEXT): {$(VPATH)}debug_counter.h
 ractor.$(OBJEXT): {$(VPATH)}defines.h
 ractor.$(OBJEXT): {$(VPATH)}encoding.h
@@ -11489,16 +11777,17 @@ ractor.$(OBJEXT): {$(VPATH)}internal/warning_push.h
 ractor.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
 ractor.$(OBJEXT): {$(VPATH)}method.h
 ractor.$(OBJEXT): {$(VPATH)}missing.h
+ractor.$(OBJEXT): {$(VPATH)}mjit.h
 ractor.$(OBJEXT): {$(VPATH)}node.h
 ractor.$(OBJEXT): {$(VPATH)}onigmo.h
 ractor.$(OBJEXT): {$(VPATH)}oniguruma.h
 ractor.$(OBJEXT): {$(VPATH)}ractor.c
 ractor.$(OBJEXT): {$(VPATH)}ractor.h
-ractor.$(OBJEXT): {$(VPATH)}ractor.rb
 ractor.$(OBJEXT): {$(VPATH)}ractor.rbinc
 ractor.$(OBJEXT): {$(VPATH)}ractor_core.h
 ractor.$(OBJEXT): {$(VPATH)}ruby_assert.h
 ractor.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+ractor.$(OBJEXT): {$(VPATH)}shape.h
 ractor.$(OBJEXT): {$(VPATH)}st.h
 ractor.$(OBJEXT): {$(VPATH)}subst.h
 ractor.$(OBJEXT): {$(VPATH)}thread.h
@@ -11517,6 +11806,7 @@ random.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 random.$(OBJEXT): $(top_srcdir)/internal/bits.h
 random.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 random.$(OBJEXT): $(top_srcdir)/internal/fixnum.h
+random.$(OBJEXT): $(top_srcdir)/internal/gc.h
 random.$(OBJEXT): $(top_srcdir)/internal/numeric.h
 random.$(OBJEXT): $(top_srcdir)/internal/random.h
 random.$(OBJEXT): $(top_srcdir)/internal/sanitizers.h
@@ -11688,12 +11978,14 @@ random.$(OBJEXT): {$(VPATH)}ractor.h
 random.$(OBJEXT): {$(VPATH)}random.c
 random.$(OBJEXT): {$(VPATH)}random.h
 random.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+random.$(OBJEXT): {$(VPATH)}shape.h
 random.$(OBJEXT): {$(VPATH)}siphash.c
 random.$(OBJEXT): {$(VPATH)}siphash.h
 random.$(OBJEXT): {$(VPATH)}st.h
 random.$(OBJEXT): {$(VPATH)}subst.h
 range.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 range.$(OBJEXT): $(top_srcdir)/internal/array.h
+range.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 range.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 range.$(OBJEXT): $(top_srcdir)/internal/bits.h
 range.$(OBJEXT): $(top_srcdir)/internal/compar.h
@@ -11880,6 +12172,7 @@ range.$(OBJEXT): {$(VPATH)}missing.h
 range.$(OBJEXT): {$(VPATH)}onigmo.h
 range.$(OBJEXT): {$(VPATH)}oniguruma.h
 range.$(OBJEXT): {$(VPATH)}range.c
+range.$(OBJEXT): {$(VPATH)}shape.h
 range.$(OBJEXT): {$(VPATH)}st.h
 range.$(OBJEXT): {$(VPATH)}subst.h
 rational.$(OBJEXT): $(hdrdir)/ruby/ruby.h
@@ -11896,6 +12189,7 @@ rational.$(OBJEXT): $(top_srcdir)/internal/object.h
 rational.$(OBJEXT): $(top_srcdir)/internal/rational.h
 rational.$(OBJEXT): $(top_srcdir)/internal/serial.h
 rational.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
+rational.$(OBJEXT): $(top_srcdir)/internal/variable.h
 rational.$(OBJEXT): $(top_srcdir)/internal/vm.h
 rational.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 rational.$(OBJEXT): {$(VPATH)}assert.h
@@ -11909,6 +12203,7 @@ rational.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 rational.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 rational.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 rational.$(OBJEXT): {$(VPATH)}config.h
+rational.$(OBJEXT): {$(VPATH)}constant.h
 rational.$(OBJEXT): {$(VPATH)}defines.h
 rational.$(OBJEXT): {$(VPATH)}id.h
 rational.$(OBJEXT): {$(VPATH)}id_table.h
@@ -12057,18 +12352,23 @@ rational.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
 rational.$(OBJEXT): {$(VPATH)}missing.h
 rational.$(OBJEXT): {$(VPATH)}rational.c
 rational.$(OBJEXT): {$(VPATH)}ruby_assert.h
+rational.$(OBJEXT): {$(VPATH)}shape.h
 rational.$(OBJEXT): {$(VPATH)}st.h
 rational.$(OBJEXT): {$(VPATH)}subst.h
 re.$(OBJEXT): $(hdrdir)/ruby.h
 re.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 re.$(OBJEXT): $(top_srcdir)/internal/array.h
 re.$(OBJEXT): $(top_srcdir)/internal/bits.h
+re.$(OBJEXT): $(top_srcdir)/internal/class.h
 re.$(OBJEXT): $(top_srcdir)/internal/compilers.h
+re.$(OBJEXT): $(top_srcdir)/internal/encoding.h
 re.$(OBJEXT): $(top_srcdir)/internal/gc.h
 re.$(OBJEXT): $(top_srcdir)/internal/hash.h
 re.$(OBJEXT): $(top_srcdir)/internal/imemo.h
+re.$(OBJEXT): $(top_srcdir)/internal/object.h
 re.$(OBJEXT): $(top_srcdir)/internal/ractor.h
 re.$(OBJEXT): $(top_srcdir)/internal/re.h
+re.$(OBJEXT): $(top_srcdir)/internal/serial.h
 re.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 re.$(OBJEXT): $(top_srcdir)/internal/string.h
 re.$(OBJEXT): $(top_srcdir)/internal/time.h
@@ -12251,6 +12551,7 @@ re.$(OBJEXT): {$(VPATH)}re.h
 re.$(OBJEXT): {$(VPATH)}regenc.h
 re.$(OBJEXT): {$(VPATH)}regex.h
 re.$(OBJEXT): {$(VPATH)}regint.h
+re.$(OBJEXT): {$(VPATH)}shape.h
 re.$(OBJEXT): {$(VPATH)}st.h
 re.$(OBJEXT): {$(VPATH)}subst.h
 re.$(OBJEXT): {$(VPATH)}util.h
@@ -12901,10 +13202,14 @@ regexec.$(OBJEXT): {$(VPATH)}st.h
 regexec.$(OBJEXT): {$(VPATH)}subst.h
 regparse.$(OBJEXT): $(hdrdir)/ruby.h
 regparse.$(OBJEXT): $(hdrdir)/ruby/ruby.h
+regparse.$(OBJEXT): $(top_srcdir)/internal/compilers.h
+regparse.$(OBJEXT): $(top_srcdir)/internal/sanitizers.h
+regparse.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 regparse.$(OBJEXT): {$(VPATH)}assert.h
 regparse.$(OBJEXT): {$(VPATH)}backward/2/assume.h
 regparse.$(OBJEXT): {$(VPATH)}backward/2/attributes.h
 regparse.$(OBJEXT): {$(VPATH)}backward/2/bool.h
+regparse.$(OBJEXT): {$(VPATH)}backward/2/gcc_version_since.h
 regparse.$(OBJEXT): {$(VPATH)}backward/2/inttypes.h
 regparse.$(OBJEXT): {$(VPATH)}backward/2/limits.h
 regparse.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
@@ -13242,9 +13547,11 @@ ruby.$(OBJEXT): $(hdrdir)/ruby.h
 ruby.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 ruby.$(OBJEXT): $(hdrdir)/ruby/version.h
 ruby.$(OBJEXT): $(top_srcdir)/internal/array.h
+ruby.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 ruby.$(OBJEXT): $(top_srcdir)/internal/class.h
 ruby.$(OBJEXT): $(top_srcdir)/internal/cmdlineopt.h
 ruby.$(OBJEXT): $(top_srcdir)/internal/compilers.h
+ruby.$(OBJEXT): $(top_srcdir)/internal/cont.h
 ruby.$(OBJEXT): $(top_srcdir)/internal/error.h
 ruby.$(OBJEXT): $(top_srcdir)/internal/file.h
 ruby.$(OBJEXT): $(top_srcdir)/internal/gc.h
@@ -13276,7 +13583,6 @@ ruby.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 ruby.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 ruby.$(OBJEXT): {$(VPATH)}config.h
 ruby.$(OBJEXT): {$(VPATH)}constant.h
-ruby.$(OBJEXT): {$(VPATH)}darray.h
 ruby.$(OBJEXT): {$(VPATH)}debug_counter.h
 ruby.$(OBJEXT): {$(VPATH)}defines.h
 ruby.$(OBJEXT): {$(VPATH)}dln.h
@@ -13436,6 +13742,7 @@ ruby.$(OBJEXT): {$(VPATH)}internal/variable.h
 ruby.$(OBJEXT): {$(VPATH)}internal/warning_push.h
 ruby.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
 ruby.$(OBJEXT): {$(VPATH)}io.h
+ruby.$(OBJEXT): {$(VPATH)}iseq.h
 ruby.$(OBJEXT): {$(VPATH)}method.h
 ruby.$(OBJEXT): {$(VPATH)}missing.h
 ruby.$(OBJEXT): {$(VPATH)}mjit.h
@@ -13445,6 +13752,7 @@ ruby.$(OBJEXT): {$(VPATH)}oniguruma.h
 ruby.$(OBJEXT): {$(VPATH)}ruby.c
 ruby.$(OBJEXT): {$(VPATH)}ruby_assert.h
 ruby.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+ruby.$(OBJEXT): {$(VPATH)}shape.h
 ruby.$(OBJEXT): {$(VPATH)}st.h
 ruby.$(OBJEXT): {$(VPATH)}subst.h
 ruby.$(OBJEXT): {$(VPATH)}thread.h
@@ -13460,12 +13768,14 @@ scheduler.$(OBJEXT): $(CCAN_DIR)/list/list.h
 scheduler.$(OBJEXT): $(CCAN_DIR)/str/str.h
 scheduler.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 scheduler.$(OBJEXT): $(top_srcdir)/internal/array.h
+scheduler.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 scheduler.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 scheduler.$(OBJEXT): $(top_srcdir)/internal/gc.h
 scheduler.$(OBJEXT): $(top_srcdir)/internal/imemo.h
 scheduler.$(OBJEXT): $(top_srcdir)/internal/serial.h
 scheduler.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 scheduler.$(OBJEXT): $(top_srcdir)/internal/thread.h
+scheduler.$(OBJEXT): $(top_srcdir)/internal/variable.h
 scheduler.$(OBJEXT): $(top_srcdir)/internal/vm.h
 scheduler.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 scheduler.$(OBJEXT): {$(VPATH)}assert.h
@@ -13480,11 +13790,12 @@ scheduler.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 scheduler.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 scheduler.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 scheduler.$(OBJEXT): {$(VPATH)}config.h
-scheduler.$(OBJEXT): {$(VPATH)}darray.h
+scheduler.$(OBJEXT): {$(VPATH)}constant.h
 scheduler.$(OBJEXT): {$(VPATH)}defines.h
 scheduler.$(OBJEXT): {$(VPATH)}encoding.h
 scheduler.$(OBJEXT): {$(VPATH)}fiber/scheduler.h
 scheduler.$(OBJEXT): {$(VPATH)}id.h
+scheduler.$(OBJEXT): {$(VPATH)}id_table.h
 scheduler.$(OBJEXT): {$(VPATH)}intern.h
 scheduler.$(OBJEXT): {$(VPATH)}internal.h
 scheduler.$(OBJEXT): {$(VPATH)}internal/abi.h
@@ -13646,6 +13957,7 @@ scheduler.$(OBJEXT): {$(VPATH)}oniguruma.h
 scheduler.$(OBJEXT): {$(VPATH)}ruby_assert.h
 scheduler.$(OBJEXT): {$(VPATH)}ruby_atomic.h
 scheduler.$(OBJEXT): {$(VPATH)}scheduler.c
+scheduler.$(OBJEXT): {$(VPATH)}shape.h
 scheduler.$(OBJEXT): {$(VPATH)}st.h
 scheduler.$(OBJEXT): {$(VPATH)}subst.h
 scheduler.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -13811,12 +14123,219 @@ setproctitle.$(OBJEXT): {$(VPATH)}setproctitle.c
 setproctitle.$(OBJEXT): {$(VPATH)}st.h
 setproctitle.$(OBJEXT): {$(VPATH)}subst.h
 setproctitle.$(OBJEXT): {$(VPATH)}util.h
+shape.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h
+shape.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h
+shape.$(OBJEXT): $(CCAN_DIR)/list/list.h
+shape.$(OBJEXT): $(CCAN_DIR)/str/str.h
+shape.$(OBJEXT): $(hdrdir)/ruby/ruby.h
+shape.$(OBJEXT): $(top_srcdir)/internal/array.h
+shape.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
+shape.$(OBJEXT): $(top_srcdir)/internal/class.h
+shape.$(OBJEXT): $(top_srcdir)/internal/compilers.h
+shape.$(OBJEXT): $(top_srcdir)/internal/gc.h
+shape.$(OBJEXT): $(top_srcdir)/internal/imemo.h
+shape.$(OBJEXT): $(top_srcdir)/internal/serial.h
+shape.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
+shape.$(OBJEXT): $(top_srcdir)/internal/symbol.h
+shape.$(OBJEXT): $(top_srcdir)/internal/variable.h
+shape.$(OBJEXT): $(top_srcdir)/internal/vm.h
+shape.$(OBJEXT): $(top_srcdir)/internal/warnings.h
+shape.$(OBJEXT): {$(VPATH)}assert.h
+shape.$(OBJEXT): {$(VPATH)}atomic.h
+shape.$(OBJEXT): {$(VPATH)}backward/2/assume.h
+shape.$(OBJEXT): {$(VPATH)}backward/2/attributes.h
+shape.$(OBJEXT): {$(VPATH)}backward/2/bool.h
+shape.$(OBJEXT): {$(VPATH)}backward/2/gcc_version_since.h
+shape.$(OBJEXT): {$(VPATH)}backward/2/inttypes.h
+shape.$(OBJEXT): {$(VPATH)}backward/2/limits.h
+shape.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
+shape.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
+shape.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
+shape.$(OBJEXT): {$(VPATH)}config.h
+shape.$(OBJEXT): {$(VPATH)}constant.h
+shape.$(OBJEXT): {$(VPATH)}debug_counter.h
+shape.$(OBJEXT): {$(VPATH)}defines.h
+shape.$(OBJEXT): {$(VPATH)}encoding.h
+shape.$(OBJEXT): {$(VPATH)}gc.h
+shape.$(OBJEXT): {$(VPATH)}id.h
+shape.$(OBJEXT): {$(VPATH)}id_table.h
+shape.$(OBJEXT): {$(VPATH)}intern.h
+shape.$(OBJEXT): {$(VPATH)}internal.h
+shape.$(OBJEXT): {$(VPATH)}internal/abi.h
+shape.$(OBJEXT): {$(VPATH)}internal/anyargs.h
+shape.$(OBJEXT): {$(VPATH)}internal/arithmetic.h
+shape.$(OBJEXT): {$(VPATH)}internal/arithmetic/char.h
+shape.$(OBJEXT): {$(VPATH)}internal/arithmetic/double.h
+shape.$(OBJEXT): {$(VPATH)}internal/arithmetic/fixnum.h
+shape.$(OBJEXT): {$(VPATH)}internal/arithmetic/gid_t.h
+shape.$(OBJEXT): {$(VPATH)}internal/arithmetic/int.h
+shape.$(OBJEXT): {$(VPATH)}internal/arithmetic/intptr_t.h
+shape.$(OBJEXT): {$(VPATH)}internal/arithmetic/long.h
+shape.$(OBJEXT): {$(VPATH)}internal/arithmetic/long_long.h
+shape.$(OBJEXT): {$(VPATH)}internal/arithmetic/mode_t.h
+shape.$(OBJEXT): {$(VPATH)}internal/arithmetic/off_t.h
+shape.$(OBJEXT): {$(VPATH)}internal/arithmetic/pid_t.h
+shape.$(OBJEXT): {$(VPATH)}internal/arithmetic/short.h
+shape.$(OBJEXT): {$(VPATH)}internal/arithmetic/size_t.h
+shape.$(OBJEXT): {$(VPATH)}internal/arithmetic/st_data_t.h
+shape.$(OBJEXT): {$(VPATH)}internal/arithmetic/uid_t.h
+shape.$(OBJEXT): {$(VPATH)}internal/assume.h
+shape.$(OBJEXT): {$(VPATH)}internal/attr/alloc_size.h
+shape.$(OBJEXT): {$(VPATH)}internal/attr/artificial.h
+shape.$(OBJEXT): {$(VPATH)}internal/attr/cold.h
+shape.$(OBJEXT): {$(VPATH)}internal/attr/const.h
+shape.$(OBJEXT): {$(VPATH)}internal/attr/constexpr.h
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+shape.$(OBJEXT): {$(VPATH)}internal/attr/enum_extensibility.h
+shape.$(OBJEXT): {$(VPATH)}internal/attr/error.h
+shape.$(OBJEXT): {$(VPATH)}internal/attr/flag_enum.h
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+shape.$(OBJEXT): {$(VPATH)}internal/attr/restrict.h
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+shape.$(OBJEXT): {$(VPATH)}internal/attr/weakref.h
+shape.$(OBJEXT): {$(VPATH)}internal/cast.h
+shape.$(OBJEXT): {$(VPATH)}internal/compiler_is.h
+shape.$(OBJEXT): {$(VPATH)}internal/compiler_is/apple.h
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+shape.$(OBJEXT): {$(VPATH)}internal/compiler_since.h
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+shape.$(OBJEXT): {$(VPATH)}internal/constant_p.h
+shape.$(OBJEXT): {$(VPATH)}internal/core.h
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+shape.$(OBJEXT): {$(VPATH)}internal/encoding/transcode.h
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+shape.$(OBJEXT): {$(VPATH)}internal/gc.h
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+shape.$(OBJEXT): {$(VPATH)}internal/has/feature.h
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+shape.$(OBJEXT): {$(VPATH)}internal/intern/enumerator.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/error.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/eval.h
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+shape.$(OBJEXT): {$(VPATH)}internal/intern/gc.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/hash.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/io.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/load.h
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+shape.$(OBJEXT): {$(VPATH)}internal/intern/numeric.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/object.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/parse.h
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+shape.$(OBJEXT): {$(VPATH)}internal/intern/process.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/random.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/range.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/rational.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/re.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/ruby.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/select.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/select/largesize.h
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+shape.$(OBJEXT): {$(VPATH)}internal/intern/sprintf.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/string.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/struct.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/thread.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/time.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/variable.h
+shape.$(OBJEXT): {$(VPATH)}internal/intern/vm.h
+shape.$(OBJEXT): {$(VPATH)}internal/interpreter.h
+shape.$(OBJEXT): {$(VPATH)}internal/iterator.h
+shape.$(OBJEXT): {$(VPATH)}internal/memory.h
+shape.$(OBJEXT): {$(VPATH)}internal/method.h
+shape.$(OBJEXT): {$(VPATH)}internal/module.h
+shape.$(OBJEXT): {$(VPATH)}internal/newobj.h
+shape.$(OBJEXT): {$(VPATH)}internal/rgengc.h
+shape.$(OBJEXT): {$(VPATH)}internal/scan_args.h
+shape.$(OBJEXT): {$(VPATH)}internal/special_consts.h
+shape.$(OBJEXT): {$(VPATH)}internal/static_assert.h
+shape.$(OBJEXT): {$(VPATH)}internal/stdalign.h
+shape.$(OBJEXT): {$(VPATH)}internal/stdbool.h
+shape.$(OBJEXT): {$(VPATH)}internal/symbol.h
+shape.$(OBJEXT): {$(VPATH)}internal/value.h
+shape.$(OBJEXT): {$(VPATH)}internal/value_type.h
+shape.$(OBJEXT): {$(VPATH)}internal/variable.h
+shape.$(OBJEXT): {$(VPATH)}internal/warning_push.h
+shape.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
+shape.$(OBJEXT): {$(VPATH)}method.h
+shape.$(OBJEXT): {$(VPATH)}missing.h
+shape.$(OBJEXT): {$(VPATH)}node.h
+shape.$(OBJEXT): {$(VPATH)}onigmo.h
+shape.$(OBJEXT): {$(VPATH)}oniguruma.h
+shape.$(OBJEXT): {$(VPATH)}ruby_assert.h
+shape.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+shape.$(OBJEXT): {$(VPATH)}shape.c
+shape.$(OBJEXT): {$(VPATH)}shape.h
+shape.$(OBJEXT): {$(VPATH)}st.h
+shape.$(OBJEXT): {$(VPATH)}subst.h
+shape.$(OBJEXT): {$(VPATH)}symbol.h
+shape.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
+shape.$(OBJEXT): {$(VPATH)}thread_native.h
+shape.$(OBJEXT): {$(VPATH)}variable.h
+shape.$(OBJEXT): {$(VPATH)}vm_core.h
+shape.$(OBJEXT): {$(VPATH)}vm_debug.h
+shape.$(OBJEXT): {$(VPATH)}vm_opts.h
+shape.$(OBJEXT): {$(VPATH)}vm_sync.h
 signal.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h
 signal.$(OBJEXT): $(CCAN_DIR)/container_of/container_of.h
 signal.$(OBJEXT): $(CCAN_DIR)/list/list.h
 signal.$(OBJEXT): $(CCAN_DIR)/str/str.h
 signal.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 signal.$(OBJEXT): $(top_srcdir)/internal/array.h
+signal.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 signal.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 signal.$(OBJEXT): $(top_srcdir)/internal/eval.h
 signal.$(OBJEXT): $(top_srcdir)/internal/gc.h
@@ -13827,6 +14346,7 @@ signal.$(OBJEXT): $(top_srcdir)/internal/signal.h
 signal.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 signal.$(OBJEXT): $(top_srcdir)/internal/string.h
 signal.$(OBJEXT): $(top_srcdir)/internal/thread.h
+signal.$(OBJEXT): $(top_srcdir)/internal/variable.h
 signal.$(OBJEXT): $(top_srcdir)/internal/vm.h
 signal.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 signal.$(OBJEXT): {$(VPATH)}assert.h
@@ -13841,7 +14361,7 @@ signal.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 signal.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 signal.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 signal.$(OBJEXT): {$(VPATH)}config.h
-signal.$(OBJEXT): {$(VPATH)}darray.h
+signal.$(OBJEXT): {$(VPATH)}constant.h
 signal.$(OBJEXT): {$(VPATH)}debug_counter.h
 signal.$(OBJEXT): {$(VPATH)}defines.h
 signal.$(OBJEXT): {$(VPATH)}encoding.h
@@ -13887,6 +14407,7 @@ signal.$(OBJEXT): {$(VPATH)}internal/attr/nodiscard.h
 signal.$(OBJEXT): {$(VPATH)}internal/attr/noexcept.h
 signal.$(OBJEXT): {$(VPATH)}internal/attr/noinline.h
 signal.$(OBJEXT): {$(VPATH)}internal/attr/nonnull.h
+signal.$(OBJEXT): {$(VPATH)}internal/attr/nonstring.h
 signal.$(OBJEXT): {$(VPATH)}internal/attr/noreturn.h
 signal.$(OBJEXT): {$(VPATH)}internal/attr/pure.h
 signal.$(OBJEXT): {$(VPATH)}internal/attr/restrict.h
@@ -14008,6 +14529,7 @@ signal.$(OBJEXT): {$(VPATH)}ractor.h
 signal.$(OBJEXT): {$(VPATH)}ractor_core.h
 signal.$(OBJEXT): {$(VPATH)}ruby_assert.h
 signal.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+signal.$(OBJEXT): {$(VPATH)}shape.h
 signal.$(OBJEXT): {$(VPATH)}signal.c
 signal.$(OBJEXT): {$(VPATH)}st.h
 signal.$(OBJEXT): {$(VPATH)}subst.h
@@ -14032,6 +14554,7 @@ sprintf.$(OBJEXT): $(top_srcdir)/internal/serial.h
 sprintf.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 sprintf.$(OBJEXT): $(top_srcdir)/internal/string.h
 sprintf.$(OBJEXT): $(top_srcdir)/internal/symbol.h
+sprintf.$(OBJEXT): $(top_srcdir)/internal/variable.h
 sprintf.$(OBJEXT): $(top_srcdir)/internal/vm.h
 sprintf.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 sprintf.$(OBJEXT): {$(VPATH)}assert.h
@@ -14045,6 +14568,7 @@ sprintf.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 sprintf.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 sprintf.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 sprintf.$(OBJEXT): {$(VPATH)}config.h
+sprintf.$(OBJEXT): {$(VPATH)}constant.h
 sprintf.$(OBJEXT): {$(VPATH)}defines.h
 sprintf.$(OBJEXT): {$(VPATH)}encoding.h
 sprintf.$(OBJEXT): {$(VPATH)}id.h
@@ -14206,6 +14730,7 @@ sprintf.$(OBJEXT): {$(VPATH)}onigmo.h
 sprintf.$(OBJEXT): {$(VPATH)}oniguruma.h
 sprintf.$(OBJEXT): {$(VPATH)}re.h
 sprintf.$(OBJEXT): {$(VPATH)}regex.h
+sprintf.$(OBJEXT): {$(VPATH)}shape.h
 sprintf.$(OBJEXT): {$(VPATH)}sprintf.c
 sprintf.$(OBJEXT): {$(VPATH)}st.h
 sprintf.$(OBJEXT): {$(VPATH)}subst.h
@@ -14373,11 +14898,13 @@ st.$(OBJEXT): {$(VPATH)}internal/variable.h
 st.$(OBJEXT): {$(VPATH)}internal/warning_push.h
 st.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
 st.$(OBJEXT): {$(VPATH)}missing.h
+st.$(OBJEXT): {$(VPATH)}ruby_assert.h
 st.$(OBJEXT): {$(VPATH)}st.c
 st.$(OBJEXT): {$(VPATH)}st.h
 st.$(OBJEXT): {$(VPATH)}subst.h
 strftime.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 strftime.$(OBJEXT): $(top_srcdir)/internal/compilers.h
+strftime.$(OBJEXT): $(top_srcdir)/internal/encoding.h
 strftime.$(OBJEXT): $(top_srcdir)/internal/serial.h
 strftime.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 strftime.$(OBJEXT): $(top_srcdir)/internal/string.h
@@ -14556,6 +15083,7 @@ strftime.$(OBJEXT): {$(VPATH)}timev.h
 strftime.$(OBJEXT): {$(VPATH)}util.h
 string.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 string.$(OBJEXT): $(top_srcdir)/internal/array.h
+string.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 string.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 string.$(OBJEXT): $(top_srcdir)/internal/bits.h
 string.$(OBJEXT): $(top_srcdir)/internal/class.h
@@ -14574,6 +15102,7 @@ string.$(OBJEXT): $(top_srcdir)/internal/serial.h
 string.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 string.$(OBJEXT): $(top_srcdir)/internal/string.h
 string.$(OBJEXT): $(top_srcdir)/internal/transcode.h
+string.$(OBJEXT): $(top_srcdir)/internal/variable.h
 string.$(OBJEXT): $(top_srcdir)/internal/vm.h
 string.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 string.$(OBJEXT): {$(VPATH)}assert.h
@@ -14588,6 +15117,7 @@ string.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 string.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 string.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 string.$(OBJEXT): {$(VPATH)}config.h
+string.$(OBJEXT): {$(VPATH)}constant.h
 string.$(OBJEXT): {$(VPATH)}debug_counter.h
 string.$(OBJEXT): {$(VPATH)}defines.h
 string.$(OBJEXT): {$(VPATH)}encindex.h
@@ -14634,6 +15164,7 @@ string.$(OBJEXT): {$(VPATH)}internal/attr/nodiscard.h
 string.$(OBJEXT): {$(VPATH)}internal/attr/noexcept.h
 string.$(OBJEXT): {$(VPATH)}internal/attr/noinline.h
 string.$(OBJEXT): {$(VPATH)}internal/attr/nonnull.h
+string.$(OBJEXT): {$(VPATH)}internal/attr/nonstring.h
 string.$(OBJEXT): {$(VPATH)}internal/attr/noreturn.h
 string.$(OBJEXT): {$(VPATH)}internal/attr/pure.h
 string.$(OBJEXT): {$(VPATH)}internal/attr/restrict.h
@@ -14755,6 +15286,7 @@ string.$(OBJEXT): {$(VPATH)}probes.h
 string.$(OBJEXT): {$(VPATH)}re.h
 string.$(OBJEXT): {$(VPATH)}regex.h
 string.$(OBJEXT): {$(VPATH)}ruby_assert.h
+string.$(OBJEXT): {$(VPATH)}shape.h
 string.$(OBJEXT): {$(VPATH)}st.h
 string.$(OBJEXT): {$(VPATH)}string.c
 string.$(OBJEXT): {$(VPATH)}subst.h
@@ -14798,6 +15330,7 @@ struct.$(OBJEXT): $(CCAN_DIR)/list/list.h
 struct.$(OBJEXT): $(CCAN_DIR)/str/str.h
 struct.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 struct.$(OBJEXT): $(top_srcdir)/internal/array.h
+struct.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 struct.$(OBJEXT): $(top_srcdir)/internal/class.h
 struct.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 struct.$(OBJEXT): $(top_srcdir)/internal/error.h
@@ -14811,6 +15344,7 @@ struct.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 struct.$(OBJEXT): $(top_srcdir)/internal/string.h
 struct.$(OBJEXT): $(top_srcdir)/internal/struct.h
 struct.$(OBJEXT): $(top_srcdir)/internal/symbol.h
+struct.$(OBJEXT): $(top_srcdir)/internal/variable.h
 struct.$(OBJEXT): $(top_srcdir)/internal/vm.h
 struct.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 struct.$(OBJEXT): {$(VPATH)}assert.h
@@ -14826,7 +15360,7 @@ struct.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 struct.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 struct.$(OBJEXT): {$(VPATH)}builtin.h
 struct.$(OBJEXT): {$(VPATH)}config.h
-struct.$(OBJEXT): {$(VPATH)}darray.h
+struct.$(OBJEXT): {$(VPATH)}constant.h
 struct.$(OBJEXT): {$(VPATH)}defines.h
 struct.$(OBJEXT): {$(VPATH)}encoding.h
 struct.$(OBJEXT): {$(VPATH)}id.h
@@ -14989,6 +15523,7 @@ struct.$(OBJEXT): {$(VPATH)}onigmo.h
 struct.$(OBJEXT): {$(VPATH)}oniguruma.h
 struct.$(OBJEXT): {$(VPATH)}ruby_assert.h
 struct.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+struct.$(OBJEXT): {$(VPATH)}shape.h
 struct.$(OBJEXT): {$(VPATH)}st.h
 struct.$(OBJEXT): {$(VPATH)}struct.c
 struct.$(OBJEXT): {$(VPATH)}subst.h
@@ -15008,6 +15543,7 @@ symbol.$(OBJEXT): $(top_srcdir)/internal/serial.h
 symbol.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 symbol.$(OBJEXT): $(top_srcdir)/internal/string.h
 symbol.$(OBJEXT): $(top_srcdir)/internal/symbol.h
+symbol.$(OBJEXT): $(top_srcdir)/internal/variable.h
 symbol.$(OBJEXT): $(top_srcdir)/internal/vm.h
 symbol.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 symbol.$(OBJEXT): {$(VPATH)}assert.h
@@ -15020,7 +15556,9 @@ symbol.$(OBJEXT): {$(VPATH)}backward/2/limits.h
 symbol.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 symbol.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 symbol.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
+symbol.$(OBJEXT): {$(VPATH)}builtin.h
 symbol.$(OBJEXT): {$(VPATH)}config.h
+symbol.$(OBJEXT): {$(VPATH)}constant.h
 symbol.$(OBJEXT): {$(VPATH)}debug_counter.h
 symbol.$(OBJEXT): {$(VPATH)}defines.h
 symbol.$(OBJEXT): {$(VPATH)}encoding.h
@@ -15068,6 +15606,7 @@ symbol.$(OBJEXT): {$(VPATH)}internal/attr/nodiscard.h
 symbol.$(OBJEXT): {$(VPATH)}internal/attr/noexcept.h
 symbol.$(OBJEXT): {$(VPATH)}internal/attr/noinline.h
 symbol.$(OBJEXT): {$(VPATH)}internal/attr/nonnull.h
+symbol.$(OBJEXT): {$(VPATH)}internal/attr/nonstring.h
 symbol.$(OBJEXT): {$(VPATH)}internal/attr/noreturn.h
 symbol.$(OBJEXT): {$(VPATH)}internal/attr/pure.h
 symbol.$(OBJEXT): {$(VPATH)}internal/attr/restrict.h
@@ -15186,10 +15725,13 @@ symbol.$(OBJEXT): {$(VPATH)}oniguruma.h
 symbol.$(OBJEXT): {$(VPATH)}probes.dmyh
 symbol.$(OBJEXT): {$(VPATH)}probes.h
 symbol.$(OBJEXT): {$(VPATH)}ruby_assert.h
+symbol.$(OBJEXT): {$(VPATH)}shape.h
 symbol.$(OBJEXT): {$(VPATH)}st.h
 symbol.$(OBJEXT): {$(VPATH)}subst.h
 symbol.$(OBJEXT): {$(VPATH)}symbol.c
 symbol.$(OBJEXT): {$(VPATH)}symbol.h
+symbol.$(OBJEXT): {$(VPATH)}symbol.rb
+symbol.$(OBJEXT): {$(VPATH)}symbol.rbinc
 symbol.$(OBJEXT): {$(VPATH)}vm_debug.h
 symbol.$(OBJEXT): {$(VPATH)}vm_sync.h
 thread.$(OBJEXT): $(CCAN_DIR)/check_type/check_type.h
@@ -15199,6 +15741,7 @@ thread.$(OBJEXT): $(CCAN_DIR)/str/str.h
 thread.$(OBJEXT): $(hdrdir)/ruby.h
 thread.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 thread.$(OBJEXT): $(top_srcdir)/internal/array.h
+thread.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 thread.$(OBJEXT): $(top_srcdir)/internal/bits.h
 thread.$(OBJEXT): $(top_srcdir)/internal/class.h
 thread.$(OBJEXT): $(top_srcdir)/internal/compilers.h
@@ -15216,6 +15759,7 @@ thread.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 thread.$(OBJEXT): $(top_srcdir)/internal/string.h
 thread.$(OBJEXT): $(top_srcdir)/internal/thread.h
 thread.$(OBJEXT): $(top_srcdir)/internal/time.h
+thread.$(OBJEXT): $(top_srcdir)/internal/variable.h
 thread.$(OBJEXT): $(top_srcdir)/internal/vm.h
 thread.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 thread.$(OBJEXT): {$(VPATH)}assert.h
@@ -15229,8 +15773,9 @@ thread.$(OBJEXT): {$(VPATH)}backward/2/limits.h
 thread.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 thread.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 thread.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
+thread.$(OBJEXT): {$(VPATH)}builtin.h
 thread.$(OBJEXT): {$(VPATH)}config.h
-thread.$(OBJEXT): {$(VPATH)}darray.h
+thread.$(OBJEXT): {$(VPATH)}constant.h
 thread.$(OBJEXT): {$(VPATH)}debug.h
 thread.$(OBJEXT): {$(VPATH)}debug_counter.h
 thread.$(OBJEXT): {$(VPATH)}defines.h
@@ -15404,6 +15949,7 @@ thread.$(OBJEXT): {$(VPATH)}ractor.h
 thread.$(OBJEXT): {$(VPATH)}ractor_core.h
 thread.$(OBJEXT): {$(VPATH)}ruby_assert.h
 thread.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+thread.$(OBJEXT): {$(VPATH)}shape.h
 thread.$(OBJEXT): {$(VPATH)}st.h
 thread.$(OBJEXT): {$(VPATH)}subst.h
 thread.$(OBJEXT): {$(VPATH)}thread.c
@@ -15412,20 +15958,22 @@ thread.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).c
 thread.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
 thread.$(OBJEXT): {$(VPATH)}thread_native.h
 thread.$(OBJEXT): {$(VPATH)}thread_sync.c
+thread.$(OBJEXT): {$(VPATH)}thread_sync.rbinc
 thread.$(OBJEXT): {$(VPATH)}timev.h
 thread.$(OBJEXT): {$(VPATH)}vm_core.h
 thread.$(OBJEXT): {$(VPATH)}vm_debug.h
 thread.$(OBJEXT): {$(VPATH)}vm_opts.h
 thread.$(OBJEXT): {$(VPATH)}vm_sync.h
-thread.$(OBJEXT): {$(VPATH)}yjit.h
 time.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 time.$(OBJEXT): $(top_srcdir)/internal/array.h
+time.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 time.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 time.$(OBJEXT): $(top_srcdir)/internal/bits.h
 time.$(OBJEXT): $(top_srcdir)/internal/compar.h
 time.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 time.$(OBJEXT): $(top_srcdir)/internal/fixnum.h
 time.$(OBJEXT): $(top_srcdir)/internal/gc.h
+time.$(OBJEXT): $(top_srcdir)/internal/hash.h
 time.$(OBJEXT): $(top_srcdir)/internal/numeric.h
 time.$(OBJEXT): $(top_srcdir)/internal/rational.h
 time.$(OBJEXT): $(top_srcdir)/internal/serial.h
@@ -15607,6 +16155,7 @@ time.$(OBJEXT): {$(VPATH)}missing.h
 time.$(OBJEXT): {$(VPATH)}onigmo.h
 time.$(OBJEXT): {$(VPATH)}oniguruma.h
 time.$(OBJEXT): {$(VPATH)}ruby_assert.h
+time.$(OBJEXT): {$(VPATH)}shape.h
 time.$(OBJEXT): {$(VPATH)}st.h
 time.$(OBJEXT): {$(VPATH)}subst.h
 time.$(OBJEXT): {$(VPATH)}time.c
@@ -15623,6 +16172,7 @@ transcode.$(OBJEXT): $(top_srcdir)/internal/serial.h
 transcode.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 transcode.$(OBJEXT): $(top_srcdir)/internal/string.h
 transcode.$(OBJEXT): $(top_srcdir)/internal/transcode.h
+transcode.$(OBJEXT): $(top_srcdir)/internal/variable.h
 transcode.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 transcode.$(OBJEXT): {$(VPATH)}assert.h
 transcode.$(OBJEXT): {$(VPATH)}backward/2/assume.h
@@ -15635,6 +16185,7 @@ transcode.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 transcode.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 transcode.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 transcode.$(OBJEXT): {$(VPATH)}config.h
+transcode.$(OBJEXT): {$(VPATH)}constant.h
 transcode.$(OBJEXT): {$(VPATH)}defines.h
 transcode.$(OBJEXT): {$(VPATH)}encoding.h
 transcode.$(OBJEXT): {$(VPATH)}id.h
@@ -15793,11 +16344,13 @@ transcode.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
 transcode.$(OBJEXT): {$(VPATH)}missing.h
 transcode.$(OBJEXT): {$(VPATH)}onigmo.h
 transcode.$(OBJEXT): {$(VPATH)}oniguruma.h
+transcode.$(OBJEXT): {$(VPATH)}shape.h
 transcode.$(OBJEXT): {$(VPATH)}st.h
 transcode.$(OBJEXT): {$(VPATH)}subst.h
 transcode.$(OBJEXT): {$(VPATH)}transcode.c
 transcode.$(OBJEXT): {$(VPATH)}transcode_data.h
 transient_heap.$(OBJEXT): $(hdrdir)/ruby/ruby.h
+transient_heap.$(OBJEXT): $(top_srcdir)/internal/array.h
 transient_heap.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 transient_heap.$(OBJEXT): $(top_srcdir)/internal/gc.h
 transient_heap.$(OBJEXT): $(top_srcdir)/internal/hash.h
@@ -15967,6 +16520,7 @@ transient_heap.$(OBJEXT): {$(VPATH)}internal/warning_push.h
 transient_heap.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
 transient_heap.$(OBJEXT): {$(VPATH)}missing.h
 transient_heap.$(OBJEXT): {$(VPATH)}ruby_assert.h
+transient_heap.$(OBJEXT): {$(VPATH)}shape.h
 transient_heap.$(OBJEXT): {$(VPATH)}st.h
 transient_heap.$(OBJEXT): {$(VPATH)}subst.h
 transient_heap.$(OBJEXT): {$(VPATH)}transient_heap.c
@@ -16146,6 +16700,7 @@ variable.$(OBJEXT): $(CCAN_DIR)/list/list.h
 variable.$(OBJEXT): $(CCAN_DIR)/str/str.h
 variable.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 variable.$(OBJEXT): $(top_srcdir)/internal/array.h
+variable.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 variable.$(OBJEXT): $(top_srcdir)/internal/class.h
 variable.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 variable.$(OBJEXT): $(top_srcdir)/internal/error.h
@@ -16176,7 +16731,6 @@ variable.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 variable.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 variable.$(OBJEXT): {$(VPATH)}config.h
 variable.$(OBJEXT): {$(VPATH)}constant.h
-variable.$(OBJEXT): {$(VPATH)}darray.h
 variable.$(OBJEXT): {$(VPATH)}debug_counter.h
 variable.$(OBJEXT): {$(VPATH)}defines.h
 variable.$(OBJEXT): {$(VPATH)}encoding.h
@@ -16342,6 +16896,7 @@ variable.$(OBJEXT): {$(VPATH)}ractor.h
 variable.$(OBJEXT): {$(VPATH)}ractor_core.h
 variable.$(OBJEXT): {$(VPATH)}ruby_assert.h
 variable.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+variable.$(OBJEXT): {$(VPATH)}shape.h
 variable.$(OBJEXT): {$(VPATH)}st.h
 variable.$(OBJEXT): {$(VPATH)}subst.h
 variable.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -16362,14 +16917,16 @@ version.$(OBJEXT): $(hdrdir)/ruby.h
 version.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 version.$(OBJEXT): $(hdrdir)/ruby/version.h
 version.$(OBJEXT): $(top_srcdir)/internal/array.h
+version.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
+version.$(OBJEXT): $(top_srcdir)/internal/cmdlineopt.h
 version.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 version.$(OBJEXT): $(top_srcdir)/internal/gc.h
 version.$(OBJEXT): $(top_srcdir)/internal/imemo.h
 version.$(OBJEXT): $(top_srcdir)/internal/serial.h
 version.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
+version.$(OBJEXT): $(top_srcdir)/internal/variable.h
 version.$(OBJEXT): $(top_srcdir)/internal/vm.h
 version.$(OBJEXT): $(top_srcdir)/internal/warnings.h
-version.$(OBJEXT): $(top_srcdir)/revision.h
 version.$(OBJEXT): $(top_srcdir)/version.h
 version.$(OBJEXT): {$(VPATH)}assert.h
 version.$(OBJEXT): {$(VPATH)}atomic.h
@@ -16383,10 +16940,11 @@ version.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 version.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 version.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 version.$(OBJEXT): {$(VPATH)}config.h
-version.$(OBJEXT): {$(VPATH)}darray.h
+version.$(OBJEXT): {$(VPATH)}constant.h
 version.$(OBJEXT): {$(VPATH)}debug_counter.h
 version.$(OBJEXT): {$(VPATH)}defines.h
 version.$(OBJEXT): {$(VPATH)}id.h
+version.$(OBJEXT): {$(VPATH)}id_table.h
 version.$(OBJEXT): {$(VPATH)}intern.h
 version.$(OBJEXT): {$(VPATH)}internal.h
 version.$(OBJEXT): {$(VPATH)}internal/abi.h
@@ -16533,8 +17091,10 @@ version.$(OBJEXT): {$(VPATH)}method.h
 version.$(OBJEXT): {$(VPATH)}missing.h
 version.$(OBJEXT): {$(VPATH)}mjit.h
 version.$(OBJEXT): {$(VPATH)}node.h
+version.$(OBJEXT): {$(VPATH)}revision.h
 version.$(OBJEXT): {$(VPATH)}ruby_assert.h
 version.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+version.$(OBJEXT): {$(VPATH)}shape.h
 version.$(OBJEXT): {$(VPATH)}st.h
 version.$(OBJEXT): {$(VPATH)}subst.h
 version.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -16550,6 +17110,7 @@ vm.$(OBJEXT): $(CCAN_DIR)/str/str.h
 vm.$(OBJEXT): $(hdrdir)/ruby.h
 vm.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 vm.$(OBJEXT): $(top_srcdir)/internal/array.h
+vm.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 vm.$(OBJEXT): $(top_srcdir)/internal/bignum.h
 vm.$(OBJEXT): $(top_srcdir)/internal/bits.h
 vm.$(OBJEXT): $(top_srcdir)/internal/class.h
@@ -16594,7 +17155,6 @@ vm.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 vm.$(OBJEXT): {$(VPATH)}builtin.h
 vm.$(OBJEXT): {$(VPATH)}config.h
 vm.$(OBJEXT): {$(VPATH)}constant.h
-vm.$(OBJEXT): {$(VPATH)}darray.h
 vm.$(OBJEXT): {$(VPATH)}debug_counter.h
 vm.$(OBJEXT): {$(VPATH)}defines.h
 vm.$(OBJEXT): {$(VPATH)}defs/opt_operand.def
@@ -16771,6 +17331,7 @@ vm.$(OBJEXT): {$(VPATH)}ractor.h
 vm.$(OBJEXT): {$(VPATH)}ractor_core.h
 vm.$(OBJEXT): {$(VPATH)}ruby_assert.h
 vm.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+vm.$(OBJEXT): {$(VPATH)}shape.h
 vm.$(OBJEXT): {$(VPATH)}st.h
 vm.$(OBJEXT): {$(VPATH)}subst.h
 vm.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -16800,6 +17361,7 @@ vm_backtrace.$(OBJEXT): $(CCAN_DIR)/list/list.h
 vm_backtrace.$(OBJEXT): $(CCAN_DIR)/str/str.h
 vm_backtrace.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 vm_backtrace.$(OBJEXT): $(top_srcdir)/internal/array.h
+vm_backtrace.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 vm_backtrace.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 vm_backtrace.$(OBJEXT): $(top_srcdir)/internal/error.h
 vm_backtrace.$(OBJEXT): $(top_srcdir)/internal/gc.h
@@ -16807,6 +17369,7 @@ vm_backtrace.$(OBJEXT): $(top_srcdir)/internal/imemo.h
 vm_backtrace.$(OBJEXT): $(top_srcdir)/internal/serial.h
 vm_backtrace.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 vm_backtrace.$(OBJEXT): $(top_srcdir)/internal/string.h
+vm_backtrace.$(OBJEXT): $(top_srcdir)/internal/variable.h
 vm_backtrace.$(OBJEXT): $(top_srcdir)/internal/vm.h
 vm_backtrace.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}assert.h
@@ -16821,12 +17384,13 @@ vm_backtrace.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}config.h
-vm_backtrace.$(OBJEXT): {$(VPATH)}darray.h
+vm_backtrace.$(OBJEXT): {$(VPATH)}constant.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}debug.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}defines.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}encoding.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}eval_intern.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}id.h
+vm_backtrace.$(OBJEXT): {$(VPATH)}id_table.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}intern.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}internal.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}internal/abi.h
@@ -16986,6 +17550,7 @@ vm_backtrace.$(OBJEXT): {$(VPATH)}onigmo.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}oniguruma.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}ruby_assert.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+vm_backtrace.$(OBJEXT): {$(VPATH)}shape.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}st.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}subst.h
 vm_backtrace.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -16999,6 +17564,7 @@ vm_dump.$(OBJEXT): $(CCAN_DIR)/list/list.h
 vm_dump.$(OBJEXT): $(CCAN_DIR)/str/str.h
 vm_dump.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 vm_dump.$(OBJEXT): $(top_srcdir)/internal/array.h
+vm_dump.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 vm_dump.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 vm_dump.$(OBJEXT): $(top_srcdir)/internal/gc.h
 vm_dump.$(OBJEXT): $(top_srcdir)/internal/imemo.h
@@ -17021,7 +17587,6 @@ vm_dump.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 vm_dump.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 vm_dump.$(OBJEXT): {$(VPATH)}config.h
 vm_dump.$(OBJEXT): {$(VPATH)}constant.h
-vm_dump.$(OBJEXT): {$(VPATH)}darray.h
 vm_dump.$(OBJEXT): {$(VPATH)}defines.h
 vm_dump.$(OBJEXT): {$(VPATH)}gc.h
 vm_dump.$(OBJEXT): {$(VPATH)}id.h
@@ -17177,6 +17742,7 @@ vm_dump.$(OBJEXT): {$(VPATH)}ractor.h
 vm_dump.$(OBJEXT): {$(VPATH)}ractor_core.h
 vm_dump.$(OBJEXT): {$(VPATH)}ruby_assert.h
 vm_dump.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+vm_dump.$(OBJEXT): {$(VPATH)}shape.h
 vm_dump.$(OBJEXT): {$(VPATH)}st.h
 vm_dump.$(OBJEXT): {$(VPATH)}subst.h
 vm_dump.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -17191,11 +17757,13 @@ vm_sync.$(OBJEXT): $(CCAN_DIR)/list/list.h
 vm_sync.$(OBJEXT): $(CCAN_DIR)/str/str.h
 vm_sync.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 vm_sync.$(OBJEXT): $(top_srcdir)/internal/array.h
+vm_sync.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 vm_sync.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 vm_sync.$(OBJEXT): $(top_srcdir)/internal/gc.h
 vm_sync.$(OBJEXT): $(top_srcdir)/internal/imemo.h
 vm_sync.$(OBJEXT): $(top_srcdir)/internal/serial.h
 vm_sync.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
+vm_sync.$(OBJEXT): $(top_srcdir)/internal/variable.h
 vm_sync.$(OBJEXT): $(top_srcdir)/internal/vm.h
 vm_sync.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 vm_sync.$(OBJEXT): {$(VPATH)}assert.h
@@ -17210,7 +17778,7 @@ vm_sync.$(OBJEXT): {$(VPATH)}backward/2/long_long.h
 vm_sync.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 vm_sync.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 vm_sync.$(OBJEXT): {$(VPATH)}config.h
-vm_sync.$(OBJEXT): {$(VPATH)}darray.h
+vm_sync.$(OBJEXT): {$(VPATH)}constant.h
 vm_sync.$(OBJEXT): {$(VPATH)}debug_counter.h
 vm_sync.$(OBJEXT): {$(VPATH)}defines.h
 vm_sync.$(OBJEXT): {$(VPATH)}gc.h
@@ -17365,6 +17933,7 @@ vm_sync.$(OBJEXT): {$(VPATH)}ractor.h
 vm_sync.$(OBJEXT): {$(VPATH)}ractor_core.h
 vm_sync.$(OBJEXT): {$(VPATH)}ruby_assert.h
 vm_sync.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+vm_sync.$(OBJEXT): {$(VPATH)}shape.h
 vm_sync.$(OBJEXT): {$(VPATH)}st.h
 vm_sync.$(OBJEXT): {$(VPATH)}subst.h
 vm_sync.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -17381,6 +17950,7 @@ vm_trace.$(OBJEXT): $(CCAN_DIR)/str/str.h
 vm_trace.$(OBJEXT): $(hdrdir)/ruby.h
 vm_trace.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 vm_trace.$(OBJEXT): $(top_srcdir)/internal/array.h
+vm_trace.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 vm_trace.$(OBJEXT): $(top_srcdir)/internal/compilers.h
 vm_trace.$(OBJEXT): $(top_srcdir)/internal/gc.h
 vm_trace.$(OBJEXT): $(top_srcdir)/internal/hash.h
@@ -17388,6 +17958,7 @@ vm_trace.$(OBJEXT): $(top_srcdir)/internal/imemo.h
 vm_trace.$(OBJEXT): $(top_srcdir)/internal/serial.h
 vm_trace.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 vm_trace.$(OBJEXT): $(top_srcdir)/internal/symbol.h
+vm_trace.$(OBJEXT): $(top_srcdir)/internal/variable.h
 vm_trace.$(OBJEXT): $(top_srcdir)/internal/vm.h
 vm_trace.$(OBJEXT): $(top_srcdir)/internal/warnings.h
 vm_trace.$(OBJEXT): {$(VPATH)}assert.h
@@ -17403,13 +17974,14 @@ vm_trace.$(OBJEXT): {$(VPATH)}backward/2/stdalign.h
 vm_trace.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 vm_trace.$(OBJEXT): {$(VPATH)}builtin.h
 vm_trace.$(OBJEXT): {$(VPATH)}config.h
-vm_trace.$(OBJEXT): {$(VPATH)}darray.h
+vm_trace.$(OBJEXT): {$(VPATH)}constant.h
 vm_trace.$(OBJEXT): {$(VPATH)}debug.h
 vm_trace.$(OBJEXT): {$(VPATH)}debug_counter.h
 vm_trace.$(OBJEXT): {$(VPATH)}defines.h
 vm_trace.$(OBJEXT): {$(VPATH)}encoding.h
 vm_trace.$(OBJEXT): {$(VPATH)}eval_intern.h
 vm_trace.$(OBJEXT): {$(VPATH)}id.h
+vm_trace.$(OBJEXT): {$(VPATH)}id_table.h
 vm_trace.$(OBJEXT): {$(VPATH)}intern.h
 vm_trace.$(OBJEXT): {$(VPATH)}internal.h
 vm_trace.$(OBJEXT): {$(VPATH)}internal/abi.h
@@ -17571,6 +18143,7 @@ vm_trace.$(OBJEXT): {$(VPATH)}oniguruma.h
 vm_trace.$(OBJEXT): {$(VPATH)}ractor.h
 vm_trace.$(OBJEXT): {$(VPATH)}ruby_assert.h
 vm_trace.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+vm_trace.$(OBJEXT): {$(VPATH)}shape.h
 vm_trace.$(OBJEXT): {$(VPATH)}st.h
 vm_trace.$(OBJEXT): {$(VPATH)}subst.h
 vm_trace.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -17586,19 +18159,19 @@ yjit.$(OBJEXT): $(CCAN_DIR)/list/list.h
 yjit.$(OBJEXT): $(CCAN_DIR)/str/str.h
 yjit.$(OBJEXT): $(hdrdir)/ruby/ruby.h
 yjit.$(OBJEXT): $(top_srcdir)/internal/array.h
+yjit.$(OBJEXT): $(top_srcdir)/internal/basic_operators.h
 yjit.$(OBJEXT): $(top_srcdir)/internal/class.h
 yjit.$(OBJEXT): $(top_srcdir)/internal/compile.h
 yjit.$(OBJEXT): $(top_srcdir)/internal/compilers.h
+yjit.$(OBJEXT): $(top_srcdir)/internal/cont.h
+yjit.$(OBJEXT): $(top_srcdir)/internal/fixnum.h
 yjit.$(OBJEXT): $(top_srcdir)/internal/gc.h
 yjit.$(OBJEXT): $(top_srcdir)/internal/hash.h
 yjit.$(OBJEXT): $(top_srcdir)/internal/imemo.h
-yjit.$(OBJEXT): $(top_srcdir)/internal/object.h
-yjit.$(OBJEXT): $(top_srcdir)/internal/re.h
 yjit.$(OBJEXT): $(top_srcdir)/internal/sanitizers.h
 yjit.$(OBJEXT): $(top_srcdir)/internal/serial.h
 yjit.$(OBJEXT): $(top_srcdir)/internal/static_assert.h
 yjit.$(OBJEXT): $(top_srcdir)/internal/string.h
-yjit.$(OBJEXT): $(top_srcdir)/internal/struct.h
 yjit.$(OBJEXT): $(top_srcdir)/internal/variable.h
 yjit.$(OBJEXT): $(top_srcdir)/internal/vm.h
 yjit.$(OBJEXT): $(top_srcdir)/internal/warnings.h
@@ -17616,7 +18189,7 @@ yjit.$(OBJEXT): {$(VPATH)}backward/2/stdarg.h
 yjit.$(OBJEXT): {$(VPATH)}builtin.h
 yjit.$(OBJEXT): {$(VPATH)}config.h
 yjit.$(OBJEXT): {$(VPATH)}constant.h
-yjit.$(OBJEXT): {$(VPATH)}darray.h
+yjit.$(OBJEXT): {$(VPATH)}debug.h
 yjit.$(OBJEXT): {$(VPATH)}debug_counter.h
 yjit.$(OBJEXT): {$(VPATH)}defines.h
 yjit.$(OBJEXT): {$(VPATH)}encoding.h
@@ -17788,6 +18361,7 @@ yjit.$(OBJEXT): {$(VPATH)}probes.h
 yjit.$(OBJEXT): {$(VPATH)}probes_helper.h
 yjit.$(OBJEXT): {$(VPATH)}ruby_assert.h
 yjit.$(OBJEXT): {$(VPATH)}ruby_atomic.h
+yjit.$(OBJEXT): {$(VPATH)}shape.h
 yjit.$(OBJEXT): {$(VPATH)}st.h
 yjit.$(OBJEXT): {$(VPATH)}subst.h
 yjit.$(OBJEXT): {$(VPATH)}thread_$(THREAD_MODEL).h
@@ -17795,19 +18369,10 @@ yjit.$(OBJEXT): {$(VPATH)}thread_native.h
 yjit.$(OBJEXT): {$(VPATH)}vm_callinfo.h
 yjit.$(OBJEXT): {$(VPATH)}vm_core.h
 yjit.$(OBJEXT): {$(VPATH)}vm_debug.h
+yjit.$(OBJEXT): {$(VPATH)}vm_insnhelper.h
 yjit.$(OBJEXT): {$(VPATH)}vm_opts.h
 yjit.$(OBJEXT): {$(VPATH)}vm_sync.h
 yjit.$(OBJEXT): {$(VPATH)}yjit.c
 yjit.$(OBJEXT): {$(VPATH)}yjit.h
-yjit.$(OBJEXT): {$(VPATH)}yjit.rb
 yjit.$(OBJEXT): {$(VPATH)}yjit.rbinc
-yjit.$(OBJEXT): {$(VPATH)}yjit_asm.c
-yjit.$(OBJEXT): {$(VPATH)}yjit_asm.h
-yjit.$(OBJEXT): {$(VPATH)}yjit_codegen.c
-yjit.$(OBJEXT): {$(VPATH)}yjit_codegen.h
-yjit.$(OBJEXT): {$(VPATH)}yjit_core.c
-yjit.$(OBJEXT): {$(VPATH)}yjit_core.h
-yjit.$(OBJEXT): {$(VPATH)}yjit_iface.c
-yjit.$(OBJEXT): {$(VPATH)}yjit_iface.h
-yjit.$(OBJEXT): {$(VPATH)}yjit_utils.c
 # AUTOGENERATED DEPENDENCIES END
diff --git a/compar.c b/compar.c
index 9f47a3fa62..040f77975e 100644
--- a/compar.c
+++ b/compar.c
@@ -30,13 +30,13 @@ rb_cmperr(VALUE x, VALUE y)
     VALUE classname;
 
     if (SPECIAL_CONST_P(y) || BUILTIN_TYPE(y) == T_FLOAT) {
-	classname = rb_inspect(y);
+        classname = rb_inspect(y);
     }
     else {
-	classname = rb_obj_class(y);
+        classname = rb_obj_class(y);
     }
     rb_raise(rb_eArgError, "comparison of %"PRIsVALUE" with %"PRIsVALUE" failed",
-	     rb_obj_class(x), classname);
+             rb_obj_class(x), classname);
 }
 
 static VALUE
@@ -50,12 +50,12 @@ VALUE
 rb_invcmp(VALUE x, VALUE y)
 {
     VALUE invcmp = rb_exec_recursive(invcmp_recursive, x, y);
-    if (invcmp == Qundef || NIL_P(invcmp)) {
-	return Qnil;
+    if (NIL_OR_UNDEF_P(invcmp)) {
+        return Qnil;
     }
     else {
-	int result = -rb_cmpint(invcmp, x, y);
-	return INT2FIX(result);
+        int result = -rb_cmpint(invcmp, x, y);
+        return INT2FIX(result);
     }
 }
 
@@ -167,9 +167,7 @@ cmp_le(VALUE x, VALUE y)
 static VALUE
 cmp_between(VALUE x, VALUE min, VALUE max)
 {
-    if (cmpint(x, min) < 0) return Qfalse;
-    if (cmpint(x, max) > 0) return Qfalse;
-    return Qtrue;
+    return RBOOL((cmpint(x, min) >= 0 && cmpint(x, max) <= 0));
 }
 
 /*
@@ -231,7 +229,7 @@ cmp_clamp(int argc, VALUE *argv, VALUE x)
         }
     }
     if (!NIL_P(min) && !NIL_P(max) && cmpint(min, max) > 0) {
-	rb_raise(rb_eArgError, "min argument must be smaller than max argument");
+        rb_raise(rb_eArgError, "min argument must be smaller than max argument");
     }
 
     if (!NIL_P(min)) {
diff --git a/compile.c b/compile.c
index 67641fcfb6..0452305923 100644
--- a/compile.c
+++ b/compile.c
@@ -52,10 +52,10 @@
 
 typedef struct iseq_link_element {
     enum {
-	ISEQ_ELEMENT_ANCHOR,
-	ISEQ_ELEMENT_LABEL,
-	ISEQ_ELEMENT_INSN,
-	ISEQ_ELEMENT_ADJUST,
+        ISEQ_ELEMENT_ANCHOR,
+        ISEQ_ELEMENT_LABEL,
+        ISEQ_ELEMENT_INSN,
+        ISEQ_ELEMENT_ADJUST,
         ISEQ_ELEMENT_TRACE,
     } type;
     struct iseq_link_element *next;
@@ -93,9 +93,9 @@ typedef struct iseq_insn_data {
     int sc_state;
     VALUE *operands;
     struct {
-	int line_no;
+        int line_no;
         int node_id;
-	rb_event_flag_t events;
+        rb_event_flag_t events;
     } insn_info;
 } INSN;
 
@@ -307,13 +307,13 @@ static void iseq_add_setlocal(rb_iseq_t *iseq, LINK_ANCHOR *const seq, const NOD
     ((label) ? (LABEL_REF(label), (label)->unremovable=1) : 0)
 #define ADD_CATCH_ENTRY(type, ls, le, iseqv, lc) do {				\
     VALUE _e = rb_ary_new3(5, (type),						\
-			   (VALUE)(ls) | 1, (VALUE)(le) | 1,			\
-			   (VALUE)(iseqv), (VALUE)(lc) | 1);			\
+                           (VALUE)(ls) | 1, (VALUE)(le) | 1,			\
+                           (VALUE)(iseqv), (VALUE)(lc) | 1);			\
     LABEL_UNREMOVABLE(ls);							\
     LABEL_REF(le);								\
     LABEL_REF(lc);								\
     if (NIL_P(ISEQ_COMPILE_DATA(iseq)->catch_table_ary)) \
-        RB_OBJ_WRITE(iseq, &ISEQ_COMPILE_DATA(iseq)->catch_table_ary, rb_ary_tmp_new(3)); \
+        RB_OBJ_WRITE(iseq, &ISEQ_COMPILE_DATA(iseq)->catch_table_ary, rb_ary_hidden_new(3)); \
     rb_ary_push(ISEQ_COMPILE_DATA(iseq)->catch_table_ary, freeze_hide_obj(_e));	\
 } while (0)
 
@@ -368,11 +368,11 @@ append_compile_error(const rb_iseq_t *iseq, int line, const char *fmt, ...)
     err = rb_syntax_error_append(err, file, line, -1, NULL, fmt, args);
     va_end(args);
     if (NIL_P(err_info)) {
-	RB_OBJ_WRITE(iseq, &ISEQ_COMPILE_DATA(iseq)->err_info, err);
-	rb_set_errinfo(err);
+        RB_OBJ_WRITE(iseq, &ISEQ_COMPILE_DATA(iseq)->err_info, err);
+        rb_set_errinfo(err);
     }
     else if (!err_info) {
-	RB_OBJ_WRITE(iseq, &ISEQ_COMPILE_DATA(iseq)->err_info, Qtrue);
+        RB_OBJ_WRITE(iseq, &ISEQ_COMPILE_DATA(iseq)->err_info, Qtrue);
     }
     if (compile_debug) {
         if (SPECIAL_CONST_P(err)) err = rb_eSyntaxError;
@@ -402,17 +402,17 @@ do { \
     const NODE *error_node = (node); \
     enum node_type error_type = nd_type(error_node); \
     if (error_type != (ndtype)) { \
-	COMPILE_ERROR(ERROR_ARGS_AT(error_node) \
-		      prefix ": " #ndtype " is expected, but %s", \
-		      ruby_node_name(error_type)); \
-	return errval; \
+        COMPILE_ERROR(ERROR_ARGS_AT(error_node) \
+                      prefix ": " #ndtype " is expected, but %s", \
+                      ruby_node_name(error_type)); \
+        return errval; \
     } \
 } while (0)
 
 #define EXPECT_NODE_NONULL(prefix, parent, ndtype, errval) \
 do { \
     COMPILE_ERROR(ERROR_ARGS_AT(parent) \
-		  prefix ": must be " #ndtype ", but 0"); \
+                  prefix ": must be " #ndtype ", but 0"); \
     return errval; \
 } while (0)
 
@@ -420,7 +420,7 @@ do { \
 do { \
     const NODE *error_node = (node); \
     COMPILE_ERROR(ERROR_ARGS_AT(error_node) prefix ": unknown node (%s)", \
-		  ruby_node_name(nd_type(error_node))); \
+                  ruby_node_name(nd_type(error_node))); \
     return errval; \
 } while (0)
 
@@ -510,19 +510,19 @@ verify_list(ISEQ_ARG_DECLARE const char *info, LINK_ANCHOR *const anchor)
     list = anchor->anchor.next;
     plist = &anchor->anchor;
     while (list) {
-	if (plist != list->prev) {
-	    flag += 1;
-	}
-	plist = list;
-	list = list->next;
+        if (plist != list->prev) {
+            flag += 1;
+        }
+        plist = list;
+        list = list->next;
     }
 
     if (anchor->last != plist && anchor->last != 0) {
-	flag |= 0x70000;
+        flag |= 0x70000;
     }
 
     if (flag != 0) {
-	rb_bug("list verify error: %08x (%s)", flag, info);
+        rb_bug("list verify error: %08x (%s)", flag, info);
     }
 #endif
 }
@@ -627,7 +627,7 @@ decl_branch_base(rb_iseq_t *iseq, const NODE *node, const char *type)
     VALUE branches;
 
     if (NIL_P(branch_base)) {
-        branch_base = rb_ary_tmp_new(6);
+        branch_base = rb_ary_hidden_new(6);
         rb_hash_aset(structure, key, branch_base);
         rb_ary_push(branch_base, ID2SYM(rb_intern(type)));
         rb_ary_push(branch_base, INT2FIX(first_lineno));
@@ -675,7 +675,7 @@ add_trace_branch_coverage(rb_iseq_t *iseq, LINK_ANCHOR *const seq, const NODE *n
     long counter_idx;
 
     if (NIL_P(branch)) {
-        branch = rb_ary_tmp_new(6);
+        branch = rb_ary_hidden_new(6);
         rb_hash_aset(branches, key, branch);
         rb_ary_push(branch, ID2SYM(rb_intern(type)));
         rb_ary_push(branch, INT2FIX(first_lineno));
@@ -705,11 +705,11 @@ validate_label(st_data_t name, st_data_t label, st_data_t arg)
     rb_iseq_t *iseq = (rb_iseq_t *)arg;
     LABEL *lobj = (LABEL *)label;
     if (!lobj->link.next) {
-	do {
-	    COMPILE_ERROR(iseq, lobj->position,
-			  "%"PRIsVALUE": undefined label",
-			  rb_sym2str((VALUE)name));
-	} while (0);
+        do {
+            COMPILE_ERROR(iseq, lobj->position,
+                          "%"PRIsVALUE": undefined label",
+                          rb_sym2str((VALUE)name));
+        } while (0);
     }
     return ST_CONTINUE;
 }
@@ -748,108 +748,108 @@ rb_iseq_compile_node(rb_iseq_t *iseq, const NODE *node)
 
     if (node == 0) {
         NO_CHECK(COMPILE(ret, "nil", node));
-	iseq_set_local_table(iseq, 0);
+        iseq_set_local_table(iseq, 0);
     }
     /* assume node is T_NODE */
     else if (nd_type_p(node, NODE_SCOPE)) {
-	/* iseq type of top, method, class, block */
-	iseq_set_local_table(iseq, node->nd_tbl);
-	iseq_set_arguments(iseq, ret, node->nd_args);
+        /* iseq type of top, method, class, block */
+        iseq_set_local_table(iseq, node->nd_tbl);
+        iseq_set_arguments(iseq, ret, node->nd_args);
 
         switch (ISEQ_BODY(iseq)->type) {
-	  case ISEQ_TYPE_BLOCK:
-	    {
-		LABEL *start = ISEQ_COMPILE_DATA(iseq)->start_label = NEW_LABEL(0);
-		LABEL *end = ISEQ_COMPILE_DATA(iseq)->end_label = NEW_LABEL(0);
-
-		start->rescued = LABEL_RESCUE_BEG;
-		end->rescued = LABEL_RESCUE_END;
-
-		ADD_TRACE(ret, RUBY_EVENT_B_CALL);
-                NODE dummy_line_node = generate_dummy_line_node(FIX2INT(ISEQ_BODY(iseq)->location.first_lineno), -1);
-		ADD_INSN (ret, &dummy_line_node, nop);
-		ADD_LABEL(ret, start);
-		CHECK(COMPILE(ret, "block body", node->nd_body));
-		ADD_LABEL(ret, end);
-		ADD_TRACE(ret, RUBY_EVENT_B_RETURN);
+          case ISEQ_TYPE_BLOCK:
+            {
+                LABEL *start = ISEQ_COMPILE_DATA(iseq)->start_label = NEW_LABEL(0);
+                LABEL *end = ISEQ_COMPILE_DATA(iseq)->end_label = NEW_LABEL(0);
+
+                start->rescued = LABEL_RESCUE_BEG;
+                end->rescued = LABEL_RESCUE_END;
+
+                ADD_TRACE(ret, RUBY_EVENT_B_CALL);
+                NODE dummy_line_node = generate_dummy_line_node(ISEQ_BODY(iseq)->location.first_lineno, -1);
+                ADD_INSN (ret, &dummy_line_node, nop);
+                ADD_LABEL(ret, start);
+                CHECK(COMPILE(ret, "block body", node->nd_body));
+                ADD_LABEL(ret, end);
+                ADD_TRACE(ret, RUBY_EVENT_B_RETURN);
                 ISEQ_COMPILE_DATA(iseq)->last_line = ISEQ_BODY(iseq)->location.code_location.end_pos.lineno;
 
-		/* wide range catch handler must put at last */
-		ADD_CATCH_ENTRY(CATCH_TYPE_REDO, start, end, NULL, start);
-		ADD_CATCH_ENTRY(CATCH_TYPE_NEXT, start, end, NULL, end);
-		break;
-	    }
-	  case ISEQ_TYPE_CLASS:
-	    {
-		ADD_TRACE(ret, RUBY_EVENT_CLASS);
-		CHECK(COMPILE(ret, "scoped node", node->nd_body));
-		ADD_TRACE(ret, RUBY_EVENT_END);
-		ISEQ_COMPILE_DATA(iseq)->last_line = nd_line(node);
-		break;
-	    }
-	  case ISEQ_TYPE_METHOD:
-	    {
+                /* wide range catch handler must put at last */
+                ADD_CATCH_ENTRY(CATCH_TYPE_REDO, start, end, NULL, start);
+                ADD_CATCH_ENTRY(CATCH_TYPE_NEXT, start, end, NULL, end);
+                break;
+            }
+          case ISEQ_TYPE_CLASS:
+            {
+                ADD_TRACE(ret, RUBY_EVENT_CLASS);
+                CHECK(COMPILE(ret, "scoped node", node->nd_body));
+                ADD_TRACE(ret, RUBY_EVENT_END);
+                ISEQ_COMPILE_DATA(iseq)->last_line = nd_line(node);
+                break;
+            }
+          case ISEQ_TYPE_METHOD:
+            {
                 ISEQ_COMPILE_DATA(iseq)->root_node = node->nd_body;
-		ADD_TRACE(ret, RUBY_EVENT_CALL);
-		CHECK(COMPILE(ret, "scoped node", node->nd_body));
+                ADD_TRACE(ret, RUBY_EVENT_CALL);
+                CHECK(COMPILE(ret, "scoped node", node->nd_body));
                 ISEQ_COMPILE_DATA(iseq)->root_node = node->nd_body;
-		ADD_TRACE(ret, RUBY_EVENT_RETURN);
-		ISEQ_COMPILE_DATA(iseq)->last_line = nd_line(node);
-		break;
-	    }
-	  default: {
-	    CHECK(COMPILE(ret, "scoped node", node->nd_body));
-	    break;
-	  }
-	}
+                ADD_TRACE(ret, RUBY_EVENT_RETURN);
+                ISEQ_COMPILE_DATA(iseq)->last_line = nd_line(node);
+                break;
+            }
+          default: {
+            CHECK(COMPILE(ret, "scoped node", node->nd_body));
+            break;
+          }
+        }
     }
     else {
-	const char *m;
+        const char *m;
 #define INVALID_ISEQ_TYPE(type) \
-	ISEQ_TYPE_##type: m = #type; goto invalid_iseq_type
+        ISEQ_TYPE_##type: m = #type; goto invalid_iseq_type
         switch (ISEQ_BODY(iseq)->type) {
-	  case INVALID_ISEQ_TYPE(METHOD);
-	  case INVALID_ISEQ_TYPE(CLASS);
-	  case INVALID_ISEQ_TYPE(BLOCK);
-	  case INVALID_ISEQ_TYPE(EVAL);
-	  case INVALID_ISEQ_TYPE(MAIN);
-	  case INVALID_ISEQ_TYPE(TOP);
+          case INVALID_ISEQ_TYPE(METHOD);
+          case INVALID_ISEQ_TYPE(CLASS);
+          case INVALID_ISEQ_TYPE(BLOCK);
+          case INVALID_ISEQ_TYPE(EVAL);
+          case INVALID_ISEQ_TYPE(MAIN);
+          case INVALID_ISEQ_TYPE(TOP);
 #undef INVALID_ISEQ_TYPE /* invalid iseq types end */
-	  case ISEQ_TYPE_RESCUE:
-	    iseq_set_exception_local_table(iseq);
-	    CHECK(COMPILE(ret, "rescue", node));
-	    break;
-	  case ISEQ_TYPE_ENSURE:
-	    iseq_set_exception_local_table(iseq);
-	    CHECK(COMPILE_POPPED(ret, "ensure", node));
-	    break;
-	  case ISEQ_TYPE_PLAIN:
-	    CHECK(COMPILE(ret, "ensure", node));
-	    break;
-	  default:
+          case ISEQ_TYPE_RESCUE:
+            iseq_set_exception_local_table(iseq);
+            CHECK(COMPILE(ret, "rescue", node));
+            break;
+          case ISEQ_TYPE_ENSURE:
+            iseq_set_exception_local_table(iseq);
+            CHECK(COMPILE_POPPED(ret, "ensure", node));
+            break;
+          case ISEQ_TYPE_PLAIN:
+            CHECK(COMPILE(ret, "ensure", node));
+            break;
+          default:
             COMPILE_ERROR(ERROR_ARGS "unknown scope: %d", ISEQ_BODY(iseq)->type);
-	    return COMPILE_NG;
-	  invalid_iseq_type:
-	    COMPILE_ERROR(ERROR_ARGS "compile/ISEQ_TYPE_%s should not be reached", m);
-	    return COMPILE_NG;
-	}
+            return COMPILE_NG;
+          invalid_iseq_type:
+            COMPILE_ERROR(ERROR_ARGS "compile/ISEQ_TYPE_%s should not be reached", m);
+            return COMPILE_NG;
+        }
     }
 
     if (ISEQ_BODY(iseq)->type == ISEQ_TYPE_RESCUE || ISEQ_BODY(iseq)->type == ISEQ_TYPE_ENSURE) {
         NODE dummy_line_node = generate_dummy_line_node(0, -1);
-	ADD_GETLOCAL(ret, &dummy_line_node, LVAR_ERRINFO, 0);
-	ADD_INSN1(ret, &dummy_line_node, throw, INT2FIX(0) /* continue throw */ );
+        ADD_GETLOCAL(ret, &dummy_line_node, LVAR_ERRINFO, 0);
+        ADD_INSN1(ret, &dummy_line_node, throw, INT2FIX(0) /* continue throw */ );
     }
     else {
         NODE dummy_line_node = generate_dummy_line_node(ISEQ_COMPILE_DATA(iseq)->last_line, -1);
-	ADD_INSN(ret, &dummy_line_node, leave);
+        ADD_INSN(ret, &dummy_line_node, leave);
     }
 
 #if OPT_SUPPORT_JOKE
     if (ISEQ_COMPILE_DATA(iseq)->labels_table) {
-	st_table *labels_table = ISEQ_COMPILE_DATA(iseq)->labels_table;
-	ISEQ_COMPILE_DATA(iseq)->labels_table = 0;
-	validate_labels(iseq, labels_table);
+        st_table *labels_table = ISEQ_COMPILE_DATA(iseq)->labels_table;
+        ISEQ_COMPILE_DATA(iseq)->labels_table = 0;
+        validate_labels(iseq, labels_table);
     }
 #endif
     CHECK(iseq_setup_insn(iseq, ret));
@@ -866,9 +866,9 @@ rb_iseq_translate_threaded_code(rb_iseq_t *iseq)
 
     for (i = 0; i < ISEQ_BODY(iseq)->iseq_size; /* */ ) {
         int insn = (int)ISEQ_BODY(iseq)->iseq_encoded[i];
-	int len = insn_len(insn);
-	encoded[i] = (VALUE)table[insn];
-	i += len;
+        int len = insn_len(insn);
+        encoded[i] = (VALUE)table[insn];
+        i += len;
     }
     FL_SET((VALUE)iseq, ISEQ_TRANSLATED);
 #endif
@@ -886,15 +886,15 @@ rb_iseq_original_iseq(const rb_iseq_t *iseq) /* cold path */
 
 #if OPT_DIRECT_THREADED_CODE || OPT_CALL_THREADED_CODE
     {
-	unsigned int i;
+        unsigned int i;
 
         for (i = 0; i < ISEQ_BODY(iseq)->iseq_size; /* */ ) {
-	    const void *addr = (const void *)original_code[i];
-	    const int insn = rb_vm_insn_addr2insn(addr);
+            const void *addr = (const void *)original_code[i];
+            const int insn = rb_vm_insn_addr2insn(addr);
 
-	    original_code[i] = insn;
-	    i += insn_len(insn);
-	}
+            original_code[i] = insn;
+            i += insn_len(insn);
+        }
     }
 #endif
     return original_code;
@@ -976,18 +976,18 @@ compile_data_alloc_with_arena(struct iseq_compile_data_storage **arena, size_t s
 
     if (size >= INT_MAX - padding) rb_memerror();
     if (storage->pos + size + padding > storage->size) {
-	unsigned int alloc_size = storage->size;
-
-	while (alloc_size < size + PADDING_SIZE_MAX) {
-	    if (alloc_size >= INT_MAX / 2) rb_memerror();
-	    alloc_size *= 2;
-	}
-	storage->next = (void *)ALLOC_N(char, alloc_size +
-					offsetof(struct iseq_compile_data_storage, buff));
-	storage = *arena = storage->next;
-	storage->next = 0;
-	storage->pos = 0;
-	storage->size = alloc_size;
+        unsigned int alloc_size = storage->size;
+
+        while (alloc_size < size + PADDING_SIZE_MAX) {
+            if (alloc_size >= INT_MAX / 2) rb_memerror();
+            alloc_size *= 2;
+        }
+        storage->next = (void *)ALLOC_N(char, alloc_size +
+                                        offsetof(struct iseq_compile_data_storage, buff));
+        storage = *arena = storage->next;
+        storage->next = 0;
+        storage->pos = 0;
+        storage->size = alloc_size;
 #ifdef STRICT_ALIGNMENT
         padding = calc_padding((void *)&storage->buff[storage->pos], size);
 #endif /* STRICT_ALIGNMENT */
@@ -1060,7 +1060,7 @@ ELEM_INSERT_NEXT(LINK_ELEMENT *elem1, LINK_ELEMENT *elem2)
     elem2->prev = elem1;
     elem1->next = elem2;
     if (elem2->next) {
-	elem2->next->prev = elem2;
+        elem2->next->prev = elem2;
     }
 }
 
@@ -1074,7 +1074,7 @@ ELEM_INSERT_PREV(LINK_ELEMENT *elem1, LINK_ELEMENT *elem2)
     elem2->next = elem1;
     elem1->prev = elem2;
     if (elem2->prev) {
-	elem2->prev->next = elem2;
+        elem2->prev->next = elem2;
     }
 }
 
@@ -1087,10 +1087,10 @@ ELEM_REPLACE(LINK_ELEMENT *elem1, LINK_ELEMENT *elem2)
     elem2->prev = elem1->prev;
     elem2->next = elem1->next;
     if (elem1->prev) {
-	elem1->prev->next = elem2;
+        elem1->prev->next = elem2;
     }
     if (elem1->next) {
-	elem1->next->prev = elem2;
+        elem1->next->prev = elem2;
     }
 }
 
@@ -1099,7 +1099,7 @@ ELEM_REMOVE(LINK_ELEMENT *elem)
 {
     elem->prev->next = elem->next;
     if (elem->next) {
-	elem->next->prev = elem->prev;
+        elem->next->prev = elem->prev;
     }
 }
 
@@ -1119,13 +1119,13 @@ static LINK_ELEMENT *
 ELEM_FIRST_INSN(LINK_ELEMENT *elem)
 {
     while (elem) {
-	switch (elem->type) {
-	  case ISEQ_ELEMENT_INSN:
-	  case ISEQ_ELEMENT_ADJUST:
-	    return elem;
-	  default:
-	    elem = elem->next;
-	}
+        switch (elem->type) {
+          case ISEQ_ELEMENT_INSN:
+          case ISEQ_ELEMENT_ADJUST:
+            return elem;
+          default:
+            elem = elem->next;
+        }
     }
     return NULL;
 }
@@ -1135,11 +1135,11 @@ LIST_INSN_SIZE_ONE(const LINK_ANCHOR *const anchor)
 {
     LINK_ELEMENT *first_insn = ELEM_FIRST_INSN(FIRST_ELEMENT(anchor));
     if (first_insn != NULL &&
-	ELEM_FIRST_INSN(first_insn->next) == NULL) {
-	return TRUE;
+        ELEM_FIRST_INSN(first_insn->next) == NULL) {
+        return TRUE;
     }
     else {
-	return FALSE;
+        return FALSE;
     }
 }
 
@@ -1147,10 +1147,10 @@ static int
 LIST_INSN_SIZE_ZERO(const LINK_ANCHOR *const anchor)
 {
     if (ELEM_FIRST_INSN(FIRST_ELEMENT(anchor)) == NULL) {
-	return TRUE;
+        return TRUE;
     }
     else {
-	return FALSE;
+        return FALSE;
     }
 }
 
@@ -1165,9 +1165,9 @@ static void
 APPEND_LIST(ISEQ_ARG_DECLARE LINK_ANCHOR *const anc1, LINK_ANCHOR *const anc2)
 {
     if (anc2->anchor.next) {
-	anc1->last->next = anc2->anchor.next;
-	anc2->anchor.next->prev = anc1->last;
-	anc1->last = anc2->last;
+        anc1->last->next = anc2->anchor.next;
+        anc2->anchor.next->prev = anc1->last;
+        anc1->last = anc2->last;
     }
     verify_list("append", anc1);
 }
@@ -1182,11 +1182,11 @@ debug_list(ISEQ_ARG_DECLARE LINK_ANCHOR *const anchor, LINK_ELEMENT *cur)
     LINK_ELEMENT *list = FIRST_ELEMENT(anchor);
     printf("----\n");
     printf("anch: %p, frst: %p, last: %p\n", (void *)&anchor->anchor,
-	   (void *)anchor->anchor.next, (void *)anchor->last);
+           (void *)anchor->anchor.next, (void *)anchor->last);
     while (list) {
-	printf("curr: %p, next: %p, prev: %p, type: %d\n", (void *)list, (void *)list->next,
-	       (void *)list->prev, (int)list->type);
-	list = list->next;
+        printf("curr: %p, next: %p, prev: %p, type: %d\n", (void *)list, (void *)list->next,
+               (void *)list->prev, (int)list->type);
+        list = list->next;
     }
     printf("----\n");
 
@@ -1243,9 +1243,35 @@ new_adjust_body(rb_iseq_t *iseq, LABEL *label, int line)
     return adjust;
 }
 
+static void
+iseq_insn_each_markable_object(INSN *insn, void (*func)(VALUE *, VALUE), VALUE data)
+{
+    const char *types = insn_op_types(insn->insn_id);
+    for (int j = 0; types[j]; j++) {
+        char type = types[j];
+        switch (type) {
+          case TS_CDHASH:
+          case TS_ISEQ:
+          case TS_VALUE:
+          case TS_IC: // constant path array
+          case TS_CALLDATA: // ci is stored.
+            func(&OPERAND_AT(insn, j), data);
+            break;
+          default:
+            break;
+        }
+    }
+}
+
+static void
+iseq_insn_each_object_write_barrier(VALUE *obj_ptr, VALUE iseq)
+{
+    RB_OBJ_WRITTEN(iseq, Qundef, *obj_ptr);
+}
+
 static INSN *
 new_insn_core(rb_iseq_t *iseq, const NODE *line_node,
-	      int insn_id, int argc, VALUE *argv)
+              int insn_id, int argc, VALUE *argv)
 {
     INSN *iobj = compile_data_alloc_insn(iseq);
 
@@ -1260,6 +1286,9 @@ new_insn_core(rb_iseq_t *iseq, const NODE *line_node,
     iobj->operands = argv;
     iobj->operand_size = argc;
     iobj->sc_state = 0;
+
+    iseq_insn_each_markable_object(iobj, iseq_insn_each_object_write_barrier, (VALUE)iseq);
+
     return iobj;
 }
 
@@ -1269,14 +1298,14 @@ new_insn_body(rb_iseq_t *iseq, const NODE *const line_node, enum ruby_vminsn_typ
     VALUE *operands = 0;
     va_list argv;
     if (argc > 0) {
-	int i;
+        int i;
         va_start(argv, argc);
         operands = compile_data_alloc2(iseq, sizeof(VALUE), argc);
-	for (i = 0; i < argc; i++) {
-	    VALUE v = va_arg(argv, VALUE);
-	    operands[i] = v;
-	}
-	va_end(argv);
+        for (i = 0; i < argc; i++) {
+            VALUE v = va_arg(argv, VALUE);
+            operands[i] = v;
+        }
+        va_end(argv);
     }
     return new_insn_core(iseq, line_node, insn_id, argc, operands);
 }
@@ -1320,7 +1349,7 @@ new_insn_send(rb_iseq_t *iseq, const NODE *const line_node, ID id, VALUE argc, c
 
 static rb_iseq_t *
 new_child_iseq(rb_iseq_t *iseq, const NODE *const node,
-	       VALUE name, const rb_iseq_t *parent, enum iseq_type type, int line_no)
+               VALUE name, const rb_iseq_t *parent, enum rb_iseq_type type, int line_no)
 {
     rb_iseq_t *ret_iseq;
     rb_ast_body_t ast;
@@ -1332,8 +1361,8 @@ new_child_iseq(rb_iseq_t *iseq, const NODE *const node,
     debugs("[new_child_iseq]> ---------------------------------------\n");
     int isolated_depth = ISEQ_COMPILE_DATA(iseq)->isolated_depth;
     ret_iseq = rb_iseq_new_with_opt(&ast, name,
-				    rb_iseq_path(iseq), rb_iseq_realpath(iseq),
-                                    INT2FIX(line_no), parent,
+                                    rb_iseq_path(iseq), rb_iseq_realpath(iseq),
+                                    line_no, parent,
                                     isolated_depth ? isolated_depth + 1 : 0,
                                     type, ISEQ_COMPILE_DATA(iseq)->option);
     debugs("[new_child_iseq]< ---------------------------------------\n");
@@ -1342,14 +1371,14 @@ new_child_iseq(rb_iseq_t *iseq, const NODE *const node,
 
 static rb_iseq_t *
 new_child_iseq_with_callback(rb_iseq_t *iseq, const struct rb_iseq_new_with_callback_callback_func *ifunc,
-		     VALUE name, const rb_iseq_t *parent, enum iseq_type type, int line_no)
+                     VALUE name, const rb_iseq_t *parent, enum rb_iseq_type type, int line_no)
 {
     rb_iseq_t *ret_iseq;
 
     debugs("[new_child_iseq_with_callback]> ---------------------------------------\n");
     ret_iseq = rb_iseq_new_with_callback(ifunc, name,
-				 rb_iseq_path(iseq), rb_iseq_realpath(iseq),
-				 INT2FIX(line_no), parent, type, ISEQ_COMPILE_DATA(iseq)->option);
+                                 rb_iseq_path(iseq), rb_iseq_realpath(iseq),
+                                 line_no, parent, type, ISEQ_COMPILE_DATA(iseq)->option);
     debugs("[new_child_iseq_with_callback]< ---------------------------------------\n");
     return ret_iseq;
 }
@@ -1357,18 +1386,18 @@ new_child_iseq_with_callback(rb_iseq_t *iseq, const struct rb_iseq_new_with_call
 static void
 set_catch_except_p(struct rb_iseq_constant_body *body)
 {
-    body->catch_except_p = TRUE;
+    body->catch_except_p = true;
     if (body->parent_iseq != NULL) {
         set_catch_except_p(ISEQ_BODY(body->parent_iseq));
     }
 }
 
-/* Set body->catch_except_p to TRUE if the ISeq may catch an exception. If it is FALSE,
-   JIT-ed code may be optimized.  If we are extremely conservative, we should set TRUE
+/* Set body->catch_except_p to true if the ISeq may catch an exception. If it is false,
+   JIT-ed code may be optimized.  If we are extremely conservative, we should set true
    if catch table exists.  But we want to optimize while loop, which always has catch
    table entries for break/next/redo.
 
-   So this function sets TRUE for limited ISeqs with break/next/redo catch table entries
+   So this function sets true for limited ISeqs with break/next/redo catch table entries
    whose child ISeq would really raise an exception. */
 static void
 update_catch_except_flags(struct rb_iseq_constant_body *body)
@@ -1399,7 +1428,7 @@ update_catch_except_flags(struct rb_iseq_constant_body *body)
         if (entry->type != CATCH_TYPE_BREAK
             && entry->type != CATCH_TYPE_NEXT
             && entry->type != CATCH_TYPE_REDO) {
-            body->catch_except_p = TRUE;
+            body->catch_except_p = true;
             break;
         }
     }
@@ -1418,7 +1447,7 @@ iseq_insert_nop_between_end_and_cont(rb_iseq_t *iseq)
         LINK_ELEMENT *cont = (LINK_ELEMENT *)(ptr[4] & ~1);
         LINK_ELEMENT *e;
 
-        enum catch_type ct = (enum catch_type)(ptr[0] & 0xffff);
+        enum rb_catch_type ct = (enum rb_catch_type)(ptr[0] & 0xffff);
 
         if (ct != CATCH_TYPE_BREAK
             && ct != CATCH_TYPE_NEXT
@@ -1440,31 +1469,31 @@ static int
 iseq_setup_insn(rb_iseq_t *iseq, LINK_ANCHOR *const anchor)
 {
     if (RTEST(ISEQ_COMPILE_DATA(iseq)->err_info))
-	return COMPILE_NG;
+        return COMPILE_NG;
 
     /* debugs("[compile step 2] (iseq_array_to_linkedlist)\n"); */
 
     if (compile_debug > 5)
-	dump_disasm_list(FIRST_ELEMENT(anchor));
+        dump_disasm_list(FIRST_ELEMENT(anchor));
 
     debugs("[compile step 3.1 (iseq_optimize)]\n");
     iseq_optimize(iseq, anchor);
 
     if (compile_debug > 5)
-	dump_disasm_list(FIRST_ELEMENT(anchor));
+        dump_disasm_list(FIRST_ELEMENT(anchor));
 
     if (ISEQ_COMPILE_DATA(iseq)->option->instructions_unification) {
-	debugs("[compile step 3.2 (iseq_insns_unification)]\n");
-	iseq_insns_unification(iseq, anchor);
-	if (compile_debug > 5)
-	    dump_disasm_list(FIRST_ELEMENT(anchor));
+        debugs("[compile step 3.2 (iseq_insns_unification)]\n");
+        iseq_insns_unification(iseq, anchor);
+        if (compile_debug > 5)
+            dump_disasm_list(FIRST_ELEMENT(anchor));
     }
 
     if (ISEQ_COMPILE_DATA(iseq)->option->stack_caching) {
-	debugs("[compile step 3.3 (iseq_set_sequence_stackcaching)]\n");
-	iseq_set_sequence_stackcaching(iseq, anchor);
-	if (compile_debug > 5)
-	    dump_disasm_list(FIRST_ELEMENT(anchor));
+        debugs("[compile step 3.3 (iseq_set_sequence_stackcaching)]\n");
+        iseq_set_sequence_stackcaching(iseq, anchor);
+        if (compile_debug > 5)
+            dump_disasm_list(FIRST_ELEMENT(anchor));
     }
 
     debugs("[compile step 3.4 (iseq_insert_nop_between_end_and_cont)]\n");
@@ -1484,7 +1513,7 @@ iseq_setup(rb_iseq_t *iseq, LINK_ANCHOR *const anchor)
     debugs("[compile step 4.1 (iseq_set_sequence)]\n");
     if (!iseq_set_sequence(iseq, anchor)) return COMPILE_NG;
     if (compile_debug > 5)
-	dump_disasm_list(FIRST_ELEMENT(anchor));
+        dump_disasm_list(FIRST_ELEMENT(anchor));
 
     debugs("[compile step 4.2 (iseq_set_exception_table)]\n");
     if (!iseq_set_exception_table(iseq)) return COMPILE_NG;
@@ -1512,8 +1541,8 @@ iseq_setup(rb_iseq_t *iseq, LINK_ANCHOR *const anchor)
 #endif
 
     if (compile_debug > 1) {
-	VALUE str = rb_iseq_disasm(iseq);
-	printf("%s\n", StringValueCStr(str));
+        VALUE str = rb_iseq_disasm(iseq);
+        printf("%s\n", StringValueCStr(str));
     }
     verify_call_cache(iseq);
     debugs("[compile step: finish]\n");
@@ -1534,7 +1563,7 @@ get_lvar_level(const rb_iseq_t *iseq)
 {
     int lev = 0;
     while (iseq != ISEQ_BODY(iseq)->local_iseq) {
-	lev++;
+        lev++;
         iseq = ISEQ_BODY(iseq)->parent_iseq;
     }
     return lev;
@@ -1547,8 +1576,8 @@ get_dyna_var_idx_at_raw(const rb_iseq_t *iseq, ID id)
 
     for (i = 0; i < ISEQ_BODY(iseq)->local_table_size; i++) {
         if (ISEQ_BODY(iseq)->local_table[i] == id) {
-	    return (int)i;
-	}
+            return (int)i;
+        }
     }
     return -1;
 }
@@ -1573,12 +1602,12 @@ get_dyna_var_idx(const rb_iseq_t *iseq, ID id, int *level, int *ls)
     const rb_iseq_t *const topmost_iseq = iseq;
 
     while (iseq) {
-	idx = get_dyna_var_idx_at_raw(iseq, id);
-	if (idx >= 0) {
-	    break;
-	}
+        idx = get_dyna_var_idx_at_raw(iseq, id);
+        if (idx >= 0) {
+            break;
+        }
         iseq = ISEQ_BODY(iseq)->parent_iseq;
-	lv++;
+        lv++;
     }
 
     if (idx < 0) {
@@ -1597,16 +1626,16 @@ iseq_local_block_param_p(const rb_iseq_t *iseq, unsigned int idx, unsigned int l
     const struct rb_iseq_constant_body *body;
     while (level > 0) {
         iseq = ISEQ_BODY(iseq)->parent_iseq;
-	level--;
+        level--;
     }
     body = ISEQ_BODY(iseq);
     if (body->local_iseq == iseq && /* local variables */
-	body->param.flags.has_block &&
-	body->local_table_size - body->param.block_start == idx) {
-	return TRUE;
+        body->param.flags.has_block &&
+        body->local_table_size - body->param.block_start == idx) {
+        return TRUE;
     }
     else {
-	return FALSE;
+        return FALSE;
     }
 }
 
@@ -1616,12 +1645,12 @@ iseq_block_param_id_p(const rb_iseq_t *iseq, ID id, int *pidx, int *plevel)
     int level, ls;
     int idx = get_dyna_var_idx(iseq, id, &level, &ls);
     if (iseq_local_block_param_p(iseq, ls - idx, level)) {
-	*pidx = ls - idx;
-	*plevel = level;
-	return TRUE;
+        *pidx = ls - idx;
+        *plevel = level;
+        return TRUE;
     }
     else {
-	return FALSE;
+        return FALSE;
     }
 }
 
@@ -1676,10 +1705,10 @@ static void
 iseq_add_getlocal(rb_iseq_t *iseq, LINK_ANCHOR *const seq, const NODE *const line_node, int idx, int level)
 {
     if (iseq_local_block_param_p(iseq, idx, level)) {
-	ADD_INSN2(seq, line_node, getblockparam, INT2FIX((idx) + VM_ENV_DATA_SIZE - 1), INT2FIX(level));
+        ADD_INSN2(seq, line_node, getblockparam, INT2FIX((idx) + VM_ENV_DATA_SIZE - 1), INT2FIX(level));
     }
     else {
-	ADD_INSN2(seq, line_node, getlocal, INT2FIX((idx) + VM_ENV_DATA_SIZE - 1), INT2FIX(level));
+        ADD_INSN2(seq, line_node, getlocal, INT2FIX((idx) + VM_ENV_DATA_SIZE - 1), INT2FIX(level));
     }
     if (level > 0) access_outer_variables(iseq, level, iseq_lvar_id(iseq, idx, level), Qfalse);
 }
@@ -1688,10 +1717,10 @@ static void
 iseq_add_setlocal(rb_iseq_t *iseq, LINK_ANCHOR *const seq, const NODE *const line_node, int idx, int level)
 {
     if (iseq_local_block_param_p(iseq, idx, level)) {
-	ADD_INSN2(seq, line_node, setblockparam, INT2FIX((idx) + VM_ENV_DATA_SIZE - 1), INT2FIX(level));
+        ADD_INSN2(seq, line_node, setblockparam, INT2FIX((idx) + VM_ENV_DATA_SIZE - 1), INT2FIX(level));
     }
     else {
-	ADD_INSN2(seq, line_node, setlocal, INT2FIX((idx) + VM_ENV_DATA_SIZE - 1), INT2FIX(level));
+        ADD_INSN2(seq, line_node, setlocal, INT2FIX((idx) + VM_ENV_DATA_SIZE - 1), INT2FIX(level));
     }
     if (level > 0) access_outer_variables(iseq, level, iseq_lvar_id(iseq, idx, level), Qtrue);
 }
@@ -1703,47 +1732,47 @@ iseq_calc_param_size(rb_iseq_t *iseq)
 {
     struct rb_iseq_constant_body *const body = ISEQ_BODY(iseq);
     if (body->param.flags.has_opt ||
-	body->param.flags.has_post ||
-	body->param.flags.has_rest ||
-	body->param.flags.has_block ||
-	body->param.flags.has_kw ||
-	body->param.flags.has_kwrest) {
-
-	if (body->param.flags.has_block) {
-	    body->param.size = body->param.block_start + 1;
-	}
-	else if (body->param.flags.has_kwrest) {
-	    body->param.size = body->param.keyword->rest_start + 1;
-	}
-	else if (body->param.flags.has_kw) {
-	    body->param.size = body->param.keyword->bits_start + 1;
-	}
-	else if (body->param.flags.has_post) {
-	    body->param.size = body->param.post_start + body->param.post_num;
-	}
-	else if (body->param.flags.has_rest) {
-	    body->param.size = body->param.rest_start + 1;
-	}
-	else if (body->param.flags.has_opt) {
-	    body->param.size = body->param.lead_num + body->param.opt_num;
-	}
-	else {
+        body->param.flags.has_post ||
+        body->param.flags.has_rest ||
+        body->param.flags.has_block ||
+        body->param.flags.has_kw ||
+        body->param.flags.has_kwrest) {
+
+        if (body->param.flags.has_block) {
+            body->param.size = body->param.block_start + 1;
+        }
+        else if (body->param.flags.has_kwrest) {
+            body->param.size = body->param.keyword->rest_start + 1;
+        }
+        else if (body->param.flags.has_kw) {
+            body->param.size = body->param.keyword->bits_start + 1;
+        }
+        else if (body->param.flags.has_post) {
+            body->param.size = body->param.post_start + body->param.post_num;
+        }
+        else if (body->param.flags.has_rest) {
+            body->param.size = body->param.rest_start + 1;
+        }
+        else if (body->param.flags.has_opt) {
+            body->param.size = body->param.lead_num + body->param.opt_num;
+        }
+        else {
             UNREACHABLE;
-	}
+        }
     }
     else {
-	body->param.size = body->param.lead_num;
+        body->param.size = body->param.lead_num;
     }
 }
 
 static int
 iseq_set_arguments_keywords(rb_iseq_t *iseq, LINK_ANCHOR *const optargs,
-			    const struct rb_args_info *args, int arg_size)
+                            const struct rb_args_info *args, int arg_size)
 {
     const NODE *node = args->kw_args;
     struct rb_iseq_constant_body *const body = ISEQ_BODY(iseq);
     struct rb_iseq_param_keyword *keyword;
-    const VALUE default_values = rb_ary_tmp_new(1);
+    const VALUE default_values = rb_ary_hidden_new(1);
     const VALUE complex_mark = rb_str_tmp_new(0);
     int kw = 0, rkw = 0, di = 0, i;
 
@@ -1751,68 +1780,68 @@ iseq_set_arguments_keywords(rb_iseq_t *iseq, LINK_ANCHOR *const optargs,
     body->param.keyword = keyword = ZALLOC_N(struct rb_iseq_param_keyword, 1);
 
     while (node) {
-	kw++;
-	node = node->nd_next;
+        kw++;
+        node = node->nd_next;
     }
     arg_size += kw;
     keyword->bits_start = arg_size++;
 
     node = args->kw_args;
     while (node) {
-	const NODE *val_node = node->nd_body->nd_value;
-	VALUE dv;
+        const NODE *val_node = node->nd_body->nd_value;
+        VALUE dv;
 
         if (val_node == NODE_SPECIAL_REQUIRED_KEYWORD) {
-	    ++rkw;
-	}
-	else {
-	    switch (nd_type(val_node)) {
-	      case NODE_LIT:
-		dv = val_node->nd_lit;
-		break;
-	      case NODE_NIL:
-		dv = Qnil;
-		break;
-	      case NODE_TRUE:
-		dv = Qtrue;
-		break;
-	      case NODE_FALSE:
-		dv = Qfalse;
-		break;
-	      default:
+            ++rkw;
+        }
+        else {
+            switch (nd_type(val_node)) {
+              case NODE_LIT:
+                dv = val_node->nd_lit;
+                break;
+              case NODE_NIL:
+                dv = Qnil;
+                break;
+              case NODE_TRUE:
+                dv = Qtrue;
+                break;
+              case NODE_FALSE:
+                dv = Qfalse;
+                break;
+              default:
                 NO_CHECK(COMPILE_POPPED(optargs, "kwarg", node)); /* nd_type_p(node, NODE_KW_ARG) */
-		dv = complex_mark;
-	    }
+                dv = complex_mark;
+            }
 
-	    keyword->num = ++di;
-	    rb_ary_push(default_values, dv);
-	}
+            keyword->num = ++di;
+            rb_ary_push(default_values, dv);
+        }
 
-	node = node->nd_next;
+        node = node->nd_next;
     }
 
     keyword->num = kw;
 
     if (args->kw_rest_arg->nd_vid != 0) {
-	keyword->rest_start = arg_size++;
-	body->param.flags.has_kwrest = TRUE;
+        keyword->rest_start = arg_size++;
+        body->param.flags.has_kwrest = TRUE;
     }
     keyword->required_num = rkw;
     keyword->table = &body->local_table[keyword->bits_start - keyword->num];
 
     {
-	VALUE *dvs = ALLOC_N(VALUE, RARRAY_LEN(default_values));
+        VALUE *dvs = ALLOC_N(VALUE, RARRAY_LEN(default_values));
 
-	for (i = 0; i < RARRAY_LEN(default_values); i++) {
-	    VALUE dv = RARRAY_AREF(default_values, i);
-	    if (dv == complex_mark) dv = Qundef;
-	    if (!SPECIAL_CONST_P(dv)) {
-		RB_OBJ_WRITTEN(iseq, Qundef, dv);
-	    }
-	    dvs[i] = dv;
-	}
+        for (i = 0; i < RARRAY_LEN(default_values); i++) {
+            VALUE dv = RARRAY_AREF(default_values, i);
+            if (dv == complex_mark) dv = Qundef;
+            if (!SPECIAL_CONST_P(dv)) {
+                RB_OBJ_WRITTEN(iseq, Qundef, dv);
+            }
+            dvs[i] = dv;
+        }
 
-	keyword->default_values = dvs;
+        keyword->default_values = dvs;
     }
     return arg_size;
 }
@@ -1824,119 +1853,119 @@ iseq_set_arguments(rb_iseq_t *iseq, LINK_ANCHOR *const optargs, const NODE *cons
 
     if (node_args) {
         struct rb_iseq_constant_body *const body = ISEQ_BODY(iseq);
-	struct rb_args_info *args = node_args->nd_ainfo;
-	ID rest_id = 0;
-	int last_comma = 0;
-	ID block_id = 0;
-	int arg_size;
+        struct rb_args_info *args = node_args->nd_ainfo;
+        ID rest_id = 0;
+        int last_comma = 0;
+        ID block_id = 0;
+        int arg_size;
 
-	EXPECT_NODE("iseq_set_arguments", node_args, NODE_ARGS, COMPILE_NG);
+        EXPECT_NODE("iseq_set_arguments", node_args, NODE_ARGS, COMPILE_NG);
 
         body->param.flags.ruby2_keywords = args->ruby2_keywords;
-	body->param.lead_num = arg_size = (int)args->pre_args_num;
-	if (body->param.lead_num > 0) body->param.flags.has_lead = TRUE;
-	debugs("  - argc: %d\n", body->param.lead_num);
+        body->param.lead_num = arg_size = (int)args->pre_args_num;
+        if (body->param.lead_num > 0) body->param.flags.has_lead = TRUE;
+        debugs("  - argc: %d\n", body->param.lead_num);
 
-	rest_id = args->rest_arg;
+        rest_id = args->rest_arg;
         if (rest_id == NODE_SPECIAL_EXCESSIVE_COMMA) {
-	    last_comma = 1;
-	    rest_id = 0;
-	}
-	block_id = args->block_arg;
-
-	if (args->opt_args) {
-	    const NODE *node = args->opt_args;
-	    LABEL *label;
-	    VALUE labels = rb_ary_tmp_new(1);
-	    VALUE *opt_table;
-	    int i = 0, j;
-
-	    while (node) {
-		label = NEW_LABEL(nd_line(node));
-		rb_ary_push(labels, (VALUE)label | 1);
-		ADD_LABEL(optargs, label);
+            last_comma = 1;
+            rest_id = 0;
+        }
+        block_id = args->block_arg;
+
+        if (args->opt_args) {
+            const NODE *node = args->opt_args;
+            LABEL *label;
+            VALUE labels = rb_ary_hidden_new(1);
+            VALUE *opt_table;
+            int i = 0, j;
+
+            while (node) {
+                label = NEW_LABEL(nd_line(node));
+                rb_ary_push(labels, (VALUE)label | 1);
+                ADD_LABEL(optargs, label);
                 NO_CHECK(COMPILE_POPPED(optargs, "optarg", node->nd_body));
-		node = node->nd_next;
-		i += 1;
-	    }
+                node = node->nd_next;
+                i += 1;
+            }
 
-	    /* last label */
-	    label = NEW_LABEL(nd_line(node_args));
-	    rb_ary_push(labels, (VALUE)label | 1);
-	    ADD_LABEL(optargs, label);
+            /* last label */
+            label = NEW_LABEL(nd_line(node_args));
+            rb_ary_push(labels, (VALUE)label | 1);
+            ADD_LABEL(optargs, label);
 
-	    opt_table = ALLOC_N(VALUE, i+1);
+            opt_table = ALLOC_N(VALUE, i+1);
 
             MEMCPY(opt_table, RARRAY_CONST_PTR_TRANSIENT(labels), VALUE, i+1);
-	    for (j = 0; j < i+1; j++) {
-		opt_table[j] &= ~1;
-	    }
-	    rb_ary_clear(labels);
-
-	    body->param.flags.has_opt = TRUE;
-	    body->param.opt_num = i;
-	    body->param.opt_table = opt_table;
-	    arg_size += i;
-	}
-
-	if (rest_id) {
-	    body->param.rest_start = arg_size++;
-	    body->param.flags.has_rest = TRUE;
-	    assert(body->param.rest_start != -1);
-	}
-
-	if (args->first_post_arg) {
-	    body->param.post_start = arg_size;
-	    body->param.post_num = args->post_args_num;
-	    body->param.flags.has_post = TRUE;
-	    arg_size += args->post_args_num;
-
-	    if (body->param.flags.has_rest) { /* TODO: why that? */
-		body->param.post_start = body->param.rest_start + 1;
-	    }
-	}
-
-	if (args->kw_args) {
-	    arg_size = iseq_set_arguments_keywords(iseq, optargs, args, arg_size);
-	}
-	else if (args->kw_rest_arg) {
-	    struct rb_iseq_param_keyword *keyword = ZALLOC_N(struct rb_iseq_param_keyword, 1);
-	    keyword->rest_start = arg_size++;
-	    body->param.keyword = keyword;
-	    body->param.flags.has_kwrest = TRUE;
-	}
-	else if (args->no_kwarg) {
-	    body->param.flags.accepts_no_kwarg = TRUE;
-	}
-
-	if (block_id) {
-	    body->param.block_start = arg_size++;
-	    body->param.flags.has_block = TRUE;
-	}
-
-	iseq_calc_param_size(iseq);
-	body->param.size = arg_size;
-
-	if (args->pre_init) { /* m_init */
+            for (j = 0; j < i+1; j++) {
+                opt_table[j] &= ~1;
+            }
+            rb_ary_clear(labels);
+
+            body->param.flags.has_opt = TRUE;
+            body->param.opt_num = i;
+            body->param.opt_table = opt_table;
+            arg_size += i;
+        }
+
+        if (rest_id) {
+            body->param.rest_start = arg_size++;
+            body->param.flags.has_rest = TRUE;
+            assert(body->param.rest_start != -1);
+        }
+
+        if (args->first_post_arg) {
+            body->param.post_start = arg_size;
+            body->param.post_num = args->post_args_num;
+            body->param.flags.has_post = TRUE;
+            arg_size += args->post_args_num;
+
+            if (body->param.flags.has_rest) { /* TODO: why that? */
+                body->param.post_start = body->param.rest_start + 1;
+            }
+        }
+
+        if (args->kw_args) {
+            arg_size = iseq_set_arguments_keywords(iseq, optargs, args, arg_size);
+        }
+        else if (args->kw_rest_arg) {
+            struct rb_iseq_param_keyword *keyword = ZALLOC_N(struct rb_iseq_param_keyword, 1);
+            keyword->rest_start = arg_size++;
+            body->param.keyword = keyword;
+            body->param.flags.has_kwrest = TRUE;
+        }
+        else if (args->no_kwarg) {
+            body->param.flags.accepts_no_kwarg = TRUE;
+        }
+
+        if (block_id) {
+            body->param.block_start = arg_size++;
+            body->param.flags.has_block = TRUE;
+        }
+
+        iseq_calc_param_size(iseq);
+        body->param.size = arg_size;
+
+        if (args->pre_init) { /* m_init */
             NO_CHECK(COMPILE_POPPED(optargs, "init arguments (m)", args->pre_init));
-	}
-	if (args->post_init) { /* p_init */
+        }
+        if (args->post_init) { /* p_init */
             NO_CHECK(COMPILE_POPPED(optargs, "init arguments (p)", args->post_init));
-	}
+        }
 
-	if (body->type == ISEQ_TYPE_BLOCK) {
-	    if (body->param.flags.has_opt    == FALSE &&
-		body->param.flags.has_post   == FALSE &&
-		body->param.flags.has_rest   == FALSE &&
-		body->param.flags.has_kw     == FALSE &&
-		body->param.flags.has_kwrest == FALSE) {
+        if (body->type == ISEQ_TYPE_BLOCK) {
+            if (body->param.flags.has_opt    == FALSE &&
+                body->param.flags.has_post   == FALSE &&
+                body->param.flags.has_rest   == FALSE &&
+                body->param.flags.has_kw     == FALSE &&
+                body->param.flags.has_kwrest == FALSE) {
 
-		if (body->param.lead_num == 1 && last_comma == 0) {
-		    /* {|a|} */
-		    body->param.flags.ambiguous_param0 = TRUE;
-		}
-	    }
-	}
+                if (body->param.lead_num == 1 && last_comma == 0) {
+                    /* {|a|} */
+                    body->param.flags.ambiguous_param0 = TRUE;
+                }
+            }
+        }
     }
 
     return COMPILE_OK;
@@ -1948,8 +1977,8 @@ iseq_set_local_table(rb_iseq_t *iseq, const rb_ast_id_table_t *tbl)
     unsigned int size = tbl ? tbl->size : 0;
 
     if (size > 0) {
-	ID *ids = (ID *)ALLOC_N(ID, size);
-	MEMCPY(ids, tbl->ids, ID, size);
+        ID *ids = (ID *)ALLOC_N(ID, size);
+        MEMCPY(ids, tbl->ids, ID, size);
         ISEQ_BODY(iseq)->local_table = ids;
     }
     ISEQ_BODY(iseq)->local_table_size = size;
@@ -2058,18 +2087,24 @@ cdhash_set_label_i(VALUE key, VALUE val, VALUE ptr)
 static inline VALUE
 get_ivar_ic_value(rb_iseq_t *iseq,ID id)
 {
+    return INT2FIX(ISEQ_BODY(iseq)->ivc_size++);
+}
+
+static inline VALUE
+get_cvar_ic_value(rb_iseq_t *iseq,ID id)
+{
     VALUE val;
     struct rb_id_table *tbl = ISEQ_COMPILE_DATA(iseq)->ivar_cache_table;
     if (tbl) {
-	if (rb_id_table_lookup(tbl,id,&val)) {
-	    return val;
-	}
+        if (rb_id_table_lookup(tbl,id,&val)) {
+            return val;
+        }
     }
     else {
-	tbl = rb_id_table_create(1);
-	ISEQ_COMPILE_DATA(iseq)->ivar_cache_table = tbl;
+        tbl = rb_id_table_create(1);
+        ISEQ_COMPILE_DATA(iseq)->ivar_cache_table = tbl;
     }
-    val = INT2FIX(ISEQ_BODY(iseq)->is_size++);
+    val = INT2FIX(ISEQ_BODY(iseq)->icvarc_size++);
     rb_id_table_insert(tbl,id,val);
     return val;
 }
@@ -2090,113 +2125,113 @@ fix_sp_depth(rb_iseq_t *iseq, LINK_ANCHOR *const anchor)
     LINK_ELEMENT *list;
 
     for (list = FIRST_ELEMENT(anchor); list; list = list->next) {
-	if (IS_LABEL(list)) {
-	    LABEL *lobj = (LABEL *)list;
-	    lobj->set = TRUE;
-	}
+        if (IS_LABEL(list)) {
+            LABEL *lobj = (LABEL *)list;
+            lobj->set = TRUE;
+        }
     }
 
     for (list = FIRST_ELEMENT(anchor); list; list = list->next) {
-	switch (list->type) {
-	  case ISEQ_ELEMENT_INSN:
-	    {
-		int j, len, insn;
-		const char *types;
-		VALUE *operands;
-		INSN *iobj = (INSN *)list;
-
-		/* update sp */
-		sp = calc_sp_depth(sp, iobj);
-		if (sp < 0) {
-		    BADINSN_DUMP(anchor, list, NULL);
-		    COMPILE_ERROR(iseq, iobj->insn_info.line_no,
-				  "argument stack underflow (%d)", sp);
-		    return -1;
-		}
-		if (sp > stack_max) {
-		    stack_max = sp;
-		}
-
-		line = iobj->insn_info.line_no;
-		/* fprintf(stderr, "insn: %-16s, sp: %d\n", insn_name(iobj->insn_id), sp); */
-		operands = iobj->operands;
-		insn = iobj->insn_id;
-		types = insn_op_types(insn);
-		len = insn_len(insn);
-
-		/* operand check */
-		if (iobj->operand_size != len - 1) {
-		    /* printf("operand size miss! (%d, %d)\n", iobj->operand_size, len); */
-		    BADINSN_DUMP(anchor, list, NULL);
-		    COMPILE_ERROR(iseq, iobj->insn_info.line_no,
-				  "operand size miss! (%d for %d)",
-				  iobj->operand_size, len - 1);
-		    return -1;
-		}
-
-		for (j = 0; types[j]; j++) {
-		    if (types[j] == TS_OFFSET) {
-			/* label(destination position) */
-			LABEL *lobj = (LABEL *)operands[j];
-			if (!lobj->set) {
-			    BADINSN_DUMP(anchor, list, NULL);
-			    COMPILE_ERROR(iseq, iobj->insn_info.line_no,
-					  "unknown label: "LABEL_FORMAT, lobj->label_no);
-			    return -1;
-			}
-			if (lobj->sp == -1) {
-			    lobj->sp = sp;
+        switch (list->type) {
+          case ISEQ_ELEMENT_INSN:
+            {
+                int j, len, insn;
+                const char *types;
+                VALUE *operands;
+                INSN *iobj = (INSN *)list;
+
+                /* update sp */
+                sp = calc_sp_depth(sp, iobj);
+                if (sp < 0) {
+                    BADINSN_DUMP(anchor, list, NULL);
+                    COMPILE_ERROR(iseq, iobj->insn_info.line_no,
+                                  "argument stack underflow (%d)", sp);
+                    return -1;
+                }
+                if (sp > stack_max) {
+                    stack_max = sp;
+                }
+
+                line = iobj->insn_info.line_no;
+                /* fprintf(stderr, "insn: %-16s, sp: %d\n", insn_name(iobj->insn_id), sp); */
+                operands = iobj->operands;
+                insn = iobj->insn_id;
+                types = insn_op_types(insn);
+                len = insn_len(insn);
+
+                /* operand check */
+                if (iobj->operand_size != len - 1) {
+                    /* printf("operand size miss! (%d, %d)\n", iobj->operand_size, len); */
+                    BADINSN_DUMP(anchor, list, NULL);
+                    COMPILE_ERROR(iseq, iobj->insn_info.line_no,
+                                  "operand size miss! (%d for %d)",
+                                  iobj->operand_size, len - 1);
+                    return -1;
+                }
+
+                for (j = 0; types[j]; j++) {
+                    if (types[j] == TS_OFFSET) {
+                        /* label(destination position) */
+                        LABEL *lobj = (LABEL *)operands[j];
+                        if (!lobj->set) {
+                            BADINSN_DUMP(anchor, list, NULL);
+                            COMPILE_ERROR(iseq, iobj->insn_info.line_no,
+                                          "unknown label: "LABEL_FORMAT, lobj->label_no);
+                            return -1;
+                        }
+                        if (lobj->sp == -1) {
+                            lobj->sp = sp;
                         }
                         else if (lobj->sp != sp) {
                             debugs("%s:%d: sp inconsistency found but ignored (" LABEL_FORMAT " sp: %d, calculated sp: %d)\n",
                                    RSTRING_PTR(rb_iseq_path(iseq)), line,
                                    lobj->label_no, lobj->sp, sp);
                         }
-		    }
-		}
-		break;
-	    }
-	  case ISEQ_ELEMENT_LABEL:
-	    {
-		LABEL *lobj = (LABEL *)list;
-		if (lobj->sp == -1) {
-		    lobj->sp = sp;
-		}
-		else {
+                    }
+                }
+                break;
+            }
+          case ISEQ_ELEMENT_LABEL:
+            {
+                LABEL *lobj = (LABEL *)list;
+                if (lobj->sp == -1) {
+                    lobj->sp = sp;
+                }
+                else {
                     if (lobj->sp != sp) {
                         debugs("%s:%d: sp inconsistency found but ignored (" LABEL_FORMAT " sp: %d, calculated sp: %d)\n",
                                 RSTRING_PTR(rb_iseq_path(iseq)), line,
                                 lobj->label_no, lobj->sp, sp);
                     }
-		    sp = lobj->sp;
-		}
-		break;
-	    }
-	  case ISEQ_ELEMENT_TRACE:
-	    {
-		/* ignore */
-		break;
-	    }
-	  case ISEQ_ELEMENT_ADJUST:
-	    {
-		ADJUST *adjust = (ADJUST *)list;
-		int orig_sp = sp;
-
-		sp = adjust->label ? adjust->label->sp : 0;
-		if (adjust->line_no != -1 && orig_sp - sp < 0) {
-		    BADINSN_DUMP(anchor, list, NULL);
-		    COMPILE_ERROR(iseq, adjust->line_no,
-				  "iseq_set_sequence: adjust bug %d < %d",
-				  orig_sp, sp);
-		    return -1;
-		}
-		break;
-	    }
-	  default:
-	    BADINSN_DUMP(anchor, list, NULL);
-	    COMPILE_ERROR(iseq, line, "unknown list type: %d", list->type);
-	    return -1;
-	}
+                    sp = lobj->sp;
+                }
+                break;
+            }
+          case ISEQ_ELEMENT_TRACE:
+            {
+                /* ignore */
+                break;
+            }
+          case ISEQ_ELEMENT_ADJUST:
+            {
+                ADJUST *adjust = (ADJUST *)list;
+                int orig_sp = sp;
+
+                sp = adjust->label ? adjust->label->sp : 0;
+                if (adjust->line_no != -1 && orig_sp - sp < 0) {
+                    BADINSN_DUMP(anchor, list, NULL);
+                    COMPILE_ERROR(iseq, adjust->line_no,
+                                  "iseq_set_sequence: adjust bug %d < %d",
+                                  orig_sp, sp);
+                    return -1;
+                }
+                break;
+            }
+          default:
+            BADINSN_DUMP(anchor, list, NULL);
+            COMPILE_ERROR(iseq, line, "unknown list type: %d", list->type);
+            return -1;
+        }
     }
     return stack_max;
 }
@@ -2226,14 +2261,34 @@ static int
 add_adjust_info(struct iseq_insn_info_entry *insns_info, unsigned int *positions,
                 int insns_info_index, int code_index, const ADJUST *adjust)
 {
-    if (insns_info_index > 0 ||
-        insns_info[insns_info_index-1].line_no != adjust->line_no) {
-        insns_info[insns_info_index].line_no    = adjust->line_no;
-        insns_info[insns_info_index].events     = 0;
-        positions[insns_info_index]             = code_index;
-        return TRUE;
+    insns_info[insns_info_index].line_no    = adjust->line_no;
+    insns_info[insns_info_index].events     = 0;
+    positions[insns_info_index]             = code_index;
+    return TRUE;
+}
+
+static ID *
+array_to_idlist(VALUE arr)
+{
+    RUBY_ASSERT(RB_TYPE_P(arr, T_ARRAY));
+    long size = RARRAY_LEN(arr);
+    ID *ids = (ID *)ALLOC_N(ID, size + 1);
+    for (int i = 0; i < size; i++) {
+        VALUE sym = RARRAY_AREF(arr, i);
+        ids[i] = SYM2ID(sym);
     }
-    return FALSE;
+    ids[size] = 0;
+    return ids;
+}
+
+static VALUE
+idlist_to_array(const ID *ids)
+{
+    VALUE arr = rb_ary_new();
+    while (*ids) {
+        rb_ary_push(arr, ID2SYM(*ids++));
+    }
+    return arr;
 }
 
 /**
@@ -2242,7 +2297,6 @@ add_adjust_info(struct iseq_insn_info_entry *insns_info, unsigned int *positions
 static int
 iseq_set_sequence(rb_iseq_t *iseq, LINK_ANCHOR *const anchor)
 {
-    VALUE iseqv = (VALUE)iseq;
     struct iseq_insn_info_entry *insns_info;
     struct rb_iseq_constant_body *const body = ISEQ_BODY(iseq);
     unsigned int *positions;
@@ -2259,20 +2313,20 @@ iseq_set_sequence(rb_iseq_t *iseq, LINK_ANCHOR *const anchor)
     /* fix label position */
     insn_num = code_index = 0;
     for (list = FIRST_ELEMENT(anchor); list; list = list->next) {
-	switch (list->type) {
-	  case ISEQ_ELEMENT_INSN:
-	    {
-		INSN *iobj = (INSN *)list;
-		/* update sp */
-		sp = calc_sp_depth(sp, iobj);
-		insn_num++;
+        switch (list->type) {
+          case ISEQ_ELEMENT_INSN:
+            {
+                INSN *iobj = (INSN *)list;
+                /* update sp */
+                sp = calc_sp_depth(sp, iobj);
+                insn_num++;
                 events = iobj->insn_info.events |= events;
                 if (ISEQ_COVERAGE(iseq)) {
                     if (ISEQ_LINE_COVERAGE(iseq) && (events & RUBY_EVENT_COVERAGE_LINE) &&
                         !(rb_get_coverage_mode() & COVERAGE_TARGET_ONESHOT_LINES)) {
-                        int line = iobj->insn_info.line_no;
-                        if (line >= 1) {
-                            RARRAY_ASET(ISEQ_LINE_COVERAGE(iseq), line - 1, INT2FIX(0));
+                        int line = iobj->insn_info.line_no - 1;
+                        if (line >= 0 && line < RARRAY_LEN(ISEQ_LINE_COVERAGE(iseq))) {
+                            RARRAY_ASET(ISEQ_LINE_COVERAGE(iseq), line, INT2FIX(0));
                         }
                     }
                     if (ISEQ_BRANCH_COVERAGE(iseq) && (events & RUBY_EVENT_COVERAGE_BRANCH)) {
@@ -2281,144 +2335,189 @@ iseq_set_sequence(rb_iseq_t *iseq, LINK_ANCHOR *const anchor)
                         }
                         RARRAY_ASET(ISEQ_PC2BRANCHINDEX(iseq), code_index, INT2FIX(data));
                     }
-		}
+                }
                 code_index += insn_data_length(iobj);
-		events = 0;
+                events = 0;
                 data = 0;
-		break;
-	    }
-	  case ISEQ_ELEMENT_LABEL:
-	    {
-		LABEL *lobj = (LABEL *)list;
-		lobj->position = code_index;
+                break;
+            }
+          case ISEQ_ELEMENT_LABEL:
+            {
+                LABEL *lobj = (LABEL *)list;
+                lobj->position = code_index;
                 if (lobj->sp != sp) {
                     debugs("%s: sp inconsistency found but ignored (" LABEL_FORMAT " sp: %d, calculated sp: %d)\n",
                            RSTRING_PTR(rb_iseq_path(iseq)),
                            lobj->label_no, lobj->sp, sp);
                 }
-		sp = lobj->sp;
-		break;
-	    }
-	  case ISEQ_ELEMENT_TRACE:
-	    {
-		TRACE *trace = (TRACE *)list;
-		events |= trace->event;
+                sp = lobj->sp;
+                break;
+            }
+          case ISEQ_ELEMENT_TRACE:
+            {
+                TRACE *trace = (TRACE *)list;
+                events |= trace->event;
                 if (trace->event & RUBY_EVENT_COVERAGE_BRANCH) data = trace->data;
-		break;
-	    }
-	  case ISEQ_ELEMENT_ADJUST:
-	    {
-		ADJUST *adjust = (ADJUST *)list;
-		if (adjust->line_no != -1) {
-		    int orig_sp = sp;
-		    sp = adjust->label ? adjust->label->sp : 0;
-		    if (orig_sp - sp > 0) {
-			if (orig_sp - sp > 1) code_index++; /* 1 operand */
-			code_index++; /* insn */
-			insn_num++;
-		    }
-		}
-		break;
-	    }
-	  default: break;
-	}
+                break;
+            }
+          case ISEQ_ELEMENT_ADJUST:
+            {
+                ADJUST *adjust = (ADJUST *)list;
+                if (adjust->line_no != -1) {
+                    int orig_sp = sp;
+                    sp = adjust->label ? adjust->label->sp : 0;
+                    if (orig_sp - sp > 0) {
+                        if (orig_sp - sp > 1) code_index++; /* 1 operand */
+                        code_index++; /* insn */
+                        insn_num++;
+                    }
+                }
+                break;
+            }
+          default: break;
+        }
     }
 
     /* make instruction sequence */
     generated_iseq = ALLOC_N(VALUE, code_index);
     insns_info = ALLOC_N(struct iseq_insn_info_entry, insn_num);
     positions = ALLOC_N(unsigned int, insn_num);
-    body->is_entries = ZALLOC_N(union iseq_inline_storage_entry, body->is_size);
+    body->is_entries = ZALLOC_N(union iseq_inline_storage_entry, ISEQ_IS_SIZE(body));
     body->call_data = ZALLOC_N(struct rb_call_data, body->ci_size);
     ISEQ_COMPILE_DATA(iseq)->ci_index = 0;
 
+    // Calculate the bitmask buffer size.
+    // Round the generated_iseq size up to the nearest multiple
+    // of the number of bits in an unsigned long.
+
+    // Allocate enough room for the bitmask list
+    iseq_bits_t * mark_offset_bits;
+    int code_size = code_index;
+
+    iseq_bits_t tmp[1] = {0};
+    bool needs_bitmap = false;
+
+    if (ISEQ_MBITS_BUFLEN(code_index) == 1) {
+        mark_offset_bits = tmp;
+    }
+    else {
+        mark_offset_bits = ZALLOC_N(iseq_bits_t, ISEQ_MBITS_BUFLEN(code_index));
+    }
+
     list = FIRST_ELEMENT(anchor);
     insns_info_index = code_index = sp = 0;
 
     while (list) {
-	switch (list->type) {
-	  case ISEQ_ELEMENT_INSN:
-	    {
-		int j, len, insn;
-		const char *types;
-		VALUE *operands;
-		INSN *iobj = (INSN *)list;
-
-		/* update sp */
-		sp = calc_sp_depth(sp, iobj);
-		/* fprintf(stderr, "insn: %-16s, sp: %d\n", insn_name(iobj->insn_id), sp); */
-		operands = iobj->operands;
-		insn = iobj->insn_id;
-		generated_iseq[code_index] = insn;
-		types = insn_op_types(insn);
-		len = insn_len(insn);
-
-		for (j = 0; types[j]; j++) {
-		    char type = types[j];
-		    /* printf("--> [%c - (%d-%d)]\n", type, k, j); */
-		    switch (type) {
-		      case TS_OFFSET:
-			{
-			    /* label(destination position) */
-			    LABEL *lobj = (LABEL *)operands[j];
-			    generated_iseq[code_index + 1 + j] = lobj->position - (code_index + len);
-			    break;
-			}
-		      case TS_CDHASH:
-			{
-			    VALUE map = operands[j];
-			    struct cdhash_set_label_struct data;
+        switch (list->type) {
+          case ISEQ_ELEMENT_INSN:
+            {
+                int j, len, insn;
+                const char *types;
+                VALUE *operands;
+                INSN *iobj = (INSN *)list;
+
+                /* update sp */
+                sp = calc_sp_depth(sp, iobj);
+                /* fprintf(stderr, "insn: %-16s, sp: %d\n", insn_name(iobj->insn_id), sp); */
+                operands = iobj->operands;
+                insn = iobj->insn_id;
+                generated_iseq[code_index] = insn;
+                types = insn_op_types(insn);
+                len = insn_len(insn);
+
+                for (j = 0; types[j]; j++) {
+                    char type = types[j];
+
+                    /* printf("--> [%c - (%d-%d)]\n", type, k, j); */
+                    switch (type) {
+                      case TS_OFFSET:
+                        {
+                            /* label(destination position) */
+                            LABEL *lobj = (LABEL *)operands[j];
+                            generated_iseq[code_index + 1 + j] = lobj->position - (code_index + len);
+                            break;
+                        }
+                      case TS_CDHASH:
+                        {
+                            VALUE map = operands[j];
+                            struct cdhash_set_label_struct data;
                             data.hash = map;
                             data.pos = code_index;
                             data.len = len;
-			    rb_hash_foreach(map, cdhash_set_label_i, (VALUE)&data);
-
-			    rb_hash_rehash(map);
-			    freeze_hide_obj(map);
-			    generated_iseq[code_index + 1 + j] = map;
-			    RB_OBJ_WRITTEN(iseq, Qundef, map);
-                            FL_SET(iseqv, ISEQ_MARKABLE_ISEQ);
-			    break;
-			}
-		      case TS_LINDEX:
-		      case TS_NUM:	/* ulong */
-			generated_iseq[code_index + 1 + j] = FIX2INT(operands[j]);
-			break;
-		      case TS_VALUE:	/* VALUE */
-		      case TS_ISEQ:	/* iseq */
-			{
-			    VALUE v = operands[j];
-			    generated_iseq[code_index + 1 + j] = v;
-			    /* to mark ruby object */
-			    if (!SPECIAL_CONST_P(v)) {
-				RB_OBJ_WRITTEN(iseq, Qundef, v);
-                                FL_SET(iseqv, ISEQ_MARKABLE_ISEQ);
-			    }
-			    break;
-			}
-		      case TS_IC: /* inline cache */
-		      case TS_ISE: /* inline storage entry */
-              case TS_ICVARC: /* inline cvar cache */
-		      case TS_IVC: /* inline ivar cache */
-			{
-			    unsigned int ic_index = FIX2UINT(operands[j]);
-			    IC ic = (IC)&body->is_entries[ic_index];
-			    if (UNLIKELY(ic_index >= body->is_size)) {
+                            rb_hash_foreach(map, cdhash_set_label_i, (VALUE)&data);
+
+                            rb_hash_rehash(map);
+                            freeze_hide_obj(map);
+                            generated_iseq[code_index + 1 + j] = map;
+                            ISEQ_MBITS_SET(mark_offset_bits, code_index + 1 + j);
+                            RB_OBJ_WRITTEN(iseq, Qundef, map);
+                            needs_bitmap = true;
+                            break;
+                        }
+                      case TS_LINDEX:
+                      case TS_NUM:	/* ulong */
+                        generated_iseq[code_index + 1 + j] = FIX2INT(operands[j]);
+                        break;
+                      case TS_ISEQ:	/* iseq */
+                      case TS_VALUE:	/* VALUE */
+                        {
+                            VALUE v = operands[j];
+                            generated_iseq[code_index + 1 + j] = v;
+                            /* to mark ruby object */
+                            if (!SPECIAL_CONST_P(v)) {
+                                RB_OBJ_WRITTEN(iseq, Qundef, v);
+                                ISEQ_MBITS_SET(mark_offset_bits, code_index + 1 + j);
+                                needs_bitmap = true;
+                            }
+                            break;
+                        }
+                      /* [ TS_IVC | TS_ICVARC | TS_ISE | TS_IC ] */
+                      case TS_IC: /* inline cache: constants */
+                        {
+                            unsigned int ic_index = ISEQ_COMPILE_DATA(iseq)->ic_index++;
+                            IC ic = &ISEQ_IS_ENTRY_START(body, type)[ic_index].ic_cache;
+                            if (UNLIKELY(ic_index >= body->ic_size)) {
                                 BADINSN_DUMP(anchor, &iobj->link, 0);
                                 COMPILE_ERROR(iseq, iobj->insn_info.line_no,
                                               "iseq_set_sequence: ic_index overflow: index: %d, size: %d",
-                                              ic_index, body->is_size);
-			    }
-			    generated_iseq[code_index + 1 + j] = (VALUE)ic;
-                            FL_SET(iseqv, ISEQ_MARKABLE_ISEQ);
-
-                            if (insn == BIN(opt_getinlinecache) && type == TS_IC) {
-                                // Store the instruction index for opt_getinlinecache on the IC for
-                                // YJIT to invalidate code when opt_setinlinecache runs.
-                                ic->get_insn_idx = (unsigned int)code_index;
+                                              ic_index, ISEQ_IS_SIZE(body));
                             }
-			    break;
-			}
+
+                            ic->segments = array_to_idlist(operands[j]);
+
+                            generated_iseq[code_index + 1 + j] = (VALUE)ic;
+                        }
+                        break;
+                      case TS_IVC: /* inline ivar cache */
+                        {
+                            unsigned int ic_index = FIX2UINT(operands[j]);
+
+                            IVC cache = ((IVC)&body->is_entries[ic_index]);
+
+                            if (insn == BIN(setinstancevariable)) {
+                                cache->iv_set_name = SYM2ID(operands[j - 1]);
+                            }
+                            else {
+                                cache->iv_set_name = 0;
+                            }
+
+                            vm_ic_attr_index_initialize(cache, INVALID_SHAPE_ID);
+                        }
+                      case TS_ISE: /* inline storage entry: `once` insn */
+                      case TS_ICVARC: /* inline cvar cache */
+                        {
+                            unsigned int ic_index = FIX2UINT(operands[j]);
+                            IC ic = &ISEQ_IS_ENTRY_START(body, type)[ic_index].ic_cache;
+                            if (UNLIKELY(ic_index >= ISEQ_IS_SIZE(body))) {
+                                BADINSN_DUMP(anchor, &iobj->link, 0);
+                                COMPILE_ERROR(iseq, iobj->insn_info.line_no,
+                                              "iseq_set_sequence: ic_index overflow: index: %d, size: %d",
+                                              ic_index, ISEQ_IS_SIZE(body));
+                            }
+                            generated_iseq[code_index + 1 + j] = (VALUE)ic;
+
+                            break;
+                        }
                         case TS_CALLDATA:
                         {
                             const struct rb_callinfo *source_ci = (const struct rb_callinfo *)operands[j];
@@ -2429,85 +2528,105 @@ iseq_set_sequence(rb_iseq_t *iseq, LINK_ANCHOR *const anchor)
                             generated_iseq[code_index + 1 + j] = (VALUE)cd;
                             break;
                         }
-		      case TS_ID: /* ID */
-			generated_iseq[code_index + 1 + j] = SYM2ID(operands[j]);
-			break;
-		      case TS_FUNCPTR:
-			generated_iseq[code_index + 1 + j] = operands[j];
-			break;
+                      case TS_ID: /* ID */
+                        generated_iseq[code_index + 1 + j] = SYM2ID(operands[j]);
+                        break;
+                      case TS_FUNCPTR:
+                        generated_iseq[code_index + 1 + j] = operands[j];
+                        break;
                       case TS_BUILTIN:
                         generated_iseq[code_index + 1 + j] = operands[j];
                         break;
-		      default:
-			BADINSN_ERROR(iseq, iobj->insn_info.line_no,
-				      "unknown operand type: %c", type);
-			return COMPILE_NG;
-		    }
-		}
-		if (add_insn_info(insns_info, positions, insns_info_index, code_index, iobj)) insns_info_index++;
-		code_index += len;
-		break;
-	    }
-	  case ISEQ_ELEMENT_LABEL:
-	    {
-		LABEL *lobj = (LABEL *)list;
+                      default:
+                        BADINSN_ERROR(iseq, iobj->insn_info.line_no,
+                                      "unknown operand type: %c", type);
+                        return COMPILE_NG;
+                    }
+                }
+                if (add_insn_info(insns_info, positions, insns_info_index, code_index, iobj)) insns_info_index++;
+                code_index += len;
+                break;
+            }
+          case ISEQ_ELEMENT_LABEL:
+            {
+                LABEL *lobj = (LABEL *)list;
                 if (lobj->sp != sp) {
                     debugs("%s: sp inconsistency found but ignored (" LABEL_FORMAT " sp: %d, calculated sp: %d)\n",
                            RSTRING_PTR(rb_iseq_path(iseq)),
                            lobj->label_no, lobj->sp, sp);
                 }
-		sp = lobj->sp;
-		break;
-	    }
-	  case ISEQ_ELEMENT_ADJUST:
-	    {
-		ADJUST *adjust = (ADJUST *)list;
-		int orig_sp = sp;
-
-		if (adjust->label) {
-		    sp = adjust->label->sp;
-		}
-		else {
-		    sp = 0;
-		}
-
-		if (adjust->line_no != -1) {
-		    const int diff = orig_sp - sp;
-		    if (diff > 0) {
-			if (add_adjust_info(insns_info, positions, insns_info_index, code_index, adjust)) insns_info_index++;
-		    }
-		    if (diff > 1) {
-			generated_iseq[code_index++] = BIN(adjuststack);
-			generated_iseq[code_index++] = orig_sp - sp;
-		    }
-		    else if (diff == 1) {
-			generated_iseq[code_index++] = BIN(pop);
-		    }
-		    else if (diff < 0) {
-			int label_no = adjust->label ? adjust->label->label_no : -1;
-			xfree(generated_iseq);
-			xfree(insns_info);
-			xfree(positions);
-			debug_list(anchor, list);
-			COMPILE_ERROR(iseq, adjust->line_no,
-				      "iseq_set_sequence: adjust bug to %d %d < %d",
-				      label_no, orig_sp, sp);
-			return COMPILE_NG;
-		    }
-		}
-		break;
-	    }
-	  default:
-	    /* ignore */
-	    break;
-	}
-	list = list->next;
+                sp = lobj->sp;
+                break;
+            }
+          case ISEQ_ELEMENT_ADJUST:
+            {
+                ADJUST *adjust = (ADJUST *)list;
+                int orig_sp = sp;
+
+                if (adjust->label) {
+                    sp = adjust->label->sp;
+                }
+                else {
+                    sp = 0;
+                }
+
+                if (adjust->line_no != -1) {
+                    const int diff = orig_sp - sp;
+                    if (diff > 0) {
+                        if (insns_info_index == 0) {
+                            COMPILE_ERROR(iseq, adjust->line_no,
+                                          "iseq_set_sequence: adjust bug (ISEQ_ELEMENT_ADJUST must not be the first in iseq)");
+                        }
+                        if (add_adjust_info(insns_info, positions, insns_info_index, code_index, adjust)) insns_info_index++;
+                    }
+                    if (diff > 1) {
+                        generated_iseq[code_index++] = BIN(adjuststack);
+                        generated_iseq[code_index++] = orig_sp - sp;
+                    }
+                    else if (diff == 1) {
+                        generated_iseq[code_index++] = BIN(pop);
+                    }
+                    else if (diff < 0) {
+                        int label_no = adjust->label ? adjust->label->label_no : -1;
+                        xfree(generated_iseq);
+                        xfree(insns_info);
+                        xfree(positions);
+                        if (ISEQ_MBITS_BUFLEN(code_size) > 1) {
+                            xfree(mark_offset_bits);
+                        }
+                        debug_list(anchor, list);
+                        COMPILE_ERROR(iseq, adjust->line_no,
+                                      "iseq_set_sequence: adjust bug to %d %d < %d",
+                                      label_no, orig_sp, sp);
+                        return COMPILE_NG;
+                    }
+                }
+                break;
+            }
+          default:
+            /* ignore */
+            break;
+        }
+        list = list->next;
     }
 
     body->iseq_encoded = (void *)generated_iseq;
     body->iseq_size = code_index;
     body->stack_max = stack_max;
 
+    if (ISEQ_MBITS_BUFLEN(body->iseq_size) == 1) {
+        body->mark_bits.single = mark_offset_bits[0];
+    }
+    else {
+        if (needs_bitmap) {
+            body->mark_bits.list = mark_offset_bits;
+        }
+        else {
+            body->mark_bits.list = 0;
+            ruby_xfree(mark_offset_bits);
+        }
+    }
+
     /* get rid of memory leak when REALLOC failed */
     body->insns_info.body = insns_info;
     body->insns_info.positions = positions;
@@ -2541,44 +2660,48 @@ iseq_set_exception_table(rb_iseq_t *iseq)
     struct iseq_catch_table_entry *entry;
 
     ISEQ_BODY(iseq)->catch_table = NULL;
-    if (NIL_P(ISEQ_COMPILE_DATA(iseq)->catch_table_ary)) return COMPILE_OK;
-    tlen = (int)RARRAY_LEN(ISEQ_COMPILE_DATA(iseq)->catch_table_ary);
-    tptr = RARRAY_CONST_PTR_TRANSIENT(ISEQ_COMPILE_DATA(iseq)->catch_table_ary);
+
+    VALUE catch_table_ary = ISEQ_COMPILE_DATA(iseq)->catch_table_ary;
+    if (NIL_P(catch_table_ary)) return COMPILE_OK;
+    tlen = (int)RARRAY_LEN(catch_table_ary);
+    tptr = RARRAY_CONST_PTR_TRANSIENT(catch_table_ary);
 
     if (tlen > 0) {
-	struct iseq_catch_table *table = xmalloc(iseq_catch_table_bytes(tlen));
-	table->size = tlen;
+        struct iseq_catch_table *table = xmalloc(iseq_catch_table_bytes(tlen));
+        table->size = tlen;
 
-	for (i = 0; i < table->size; i++) {
+        for (i = 0; i < table->size; i++) {
             ptr = RARRAY_CONST_PTR_TRANSIENT(tptr[i]);
-	    entry = UNALIGNED_MEMBER_PTR(table, entries[i]);
-	    entry->type = (enum catch_type)(ptr[0] & 0xffff);
-	    entry->start = label_get_position((LABEL *)(ptr[1] & ~1));
-	    entry->end = label_get_position((LABEL *)(ptr[2] & ~1));
-	    entry->iseq = (rb_iseq_t *)ptr[3];
-	    RB_OBJ_WRITTEN(iseq, Qundef, entry->iseq);
-
-	    /* stack depth */
-	    if (ptr[4]) {
-		LABEL *lobj = (LABEL *)(ptr[4] & ~1);
-		entry->cont = label_get_position(lobj);
-		entry->sp = label_get_sp(lobj);
-
-		/* TODO: Dirty Hack!  Fix me */
-		if (entry->type == CATCH_TYPE_RESCUE ||
-		    entry->type == CATCH_TYPE_BREAK ||
-		    entry->type == CATCH_TYPE_NEXT) {
-		    entry->sp--;
-		}
-	    }
-	    else {
-		entry->cont = 0;
-	    }
-	}
+            entry = UNALIGNED_MEMBER_PTR(table, entries[i]);
+            entry->type = (enum rb_catch_type)(ptr[0] & 0xffff);
+            entry->start = label_get_position((LABEL *)(ptr[1] & ~1));
+            entry->end = label_get_position((LABEL *)(ptr[2] & ~1));
+            entry->iseq = (rb_iseq_t *)ptr[3];
+            RB_OBJ_WRITTEN(iseq, Qundef, entry->iseq);
+
+            /* stack depth */
+            if (ptr[4]) {
+                LABEL *lobj = (LABEL *)(ptr[4] & ~1);
+                entry->cont = label_get_position(lobj);
+                entry->sp = label_get_sp(lobj);
+
+                /* TODO: Dirty Hack!  Fix me */
+                if (entry->type == CATCH_TYPE_RESCUE ||
+                    entry->type == CATCH_TYPE_BREAK ||
+                    entry->type == CATCH_TYPE_NEXT) {
+                    entry->sp--;
+                }
+            }
+            else {
+                entry->cont = 0;
+            }
+        }
         ISEQ_BODY(iseq)->catch_table = table;
-	RB_OBJ_WRITE(iseq, &ISEQ_COMPILE_DATA(iseq)->catch_table_ary, 0); /* free */
+        RB_OBJ_WRITE(iseq, &ISEQ_COMPILE_DATA(iseq)->catch_table_ary, 0); /* free */
     }
 
+    RB_GC_GUARD(catch_table_ary);
+
     return COMPILE_OK;
 }
 
@@ -2599,8 +2722,8 @@ iseq_set_optargs_table(rb_iseq_t *iseq)
 
     if (ISEQ_BODY(iseq)->param.flags.has_opt) {
         for (i = 0; i < ISEQ_BODY(iseq)->param.opt_num + 1; i++) {
-	    opt_table[i] = label_get_position((LABEL *)opt_table[i]);
-	}
+            opt_table[i] = label_get_position((LABEL *)opt_table[i]);
+        }
     }
     return COMPILE_OK;
 }
@@ -2614,27 +2737,27 @@ get_destination_insn(INSN *iobj)
 
     list = lobj->link.next;
     while (list) {
-	switch (list->type) {
-	  case ISEQ_ELEMENT_INSN:
-	  case ISEQ_ELEMENT_ADJUST:
-	    goto found;
-	  case ISEQ_ELEMENT_LABEL:
-	    /* ignore */
-	    break;
-	  case ISEQ_ELEMENT_TRACE:
-	    {
-		TRACE *trace = (TRACE *)list;
-		events |= trace->event;
-	    }
-	    break;
-	  default: break;
-	}
-	list = list->next;
+        switch (list->type) {
+          case ISEQ_ELEMENT_INSN:
+          case ISEQ_ELEMENT_ADJUST:
+            goto found;
+          case ISEQ_ELEMENT_LABEL:
+            /* ignore */
+            break;
+          case ISEQ_ELEMENT_TRACE:
+            {
+                TRACE *trace = (TRACE *)list;
+                events |= trace->event;
+            }
+            break;
+          default: break;
+        }
+        list = list->next;
     }
   found:
     if (list && IS_INSN(list)) {
-	INSN *iobj = (INSN *)list;
-	iobj->insn_info.events |= events;
+        INSN *iobj = (INSN *)list;
+        iobj->insn_info.events |= events;
     }
     return list;
 }
@@ -2645,10 +2768,10 @@ get_next_insn(INSN *iobj)
     LINK_ELEMENT *list = iobj->link.next;
 
     while (list) {
-	if (IS_INSN(list) || IS_ADJUST(list)) {
-	    return list;
-	}
-	list = list->next;
+        if (IS_INSN(list) || IS_ADJUST(list)) {
+            return list;
+        }
+        list = list->next;
     }
     return 0;
 }
@@ -2659,10 +2782,10 @@ get_prev_insn(INSN *iobj)
     LINK_ELEMENT *list = iobj->link.prev;
 
     while (list) {
-	if (IS_INSN(list) || IS_ADJUST(list)) {
-	    return list;
-	}
-	list = list->prev;
+        if (IS_INSN(list) || IS_ADJUST(list)) {
+            return list;
+        }
+        list = list->prev;
     }
     return 0;
 }
@@ -2692,9 +2815,9 @@ find_destination(INSN *i)
 {
     int pos, len = insn_len(i->insn_id);
     for (pos = 0; pos < len; ++pos) {
-	if (insn_op_types(i->insn_id)[pos] == TS_OFFSET) {
-	    return (LABEL *)OPERAND_AT(i, pos);
-	}
+        if (insn_op_types(i->insn_id)[pos] == TS_OFFSET) {
+            return (LABEL *)OPERAND_AT(i, pos);
+        }
     }
     return 0;
 }
@@ -2710,53 +2833,51 @@ remove_unreachable_chunk(rb_iseq_t *iseq, LINK_ELEMENT *i)
     MEMZERO(unref_counts, int, nlabels);
     end = i;
     do {
-	LABEL *lab;
-	if (IS_INSN(i)) {
-	    if (IS_INSN_ID(i, leave)) {
-		end = i;
-		break;
-	    }
-	    else if ((lab = find_destination((INSN *)i)) != 0) {
-		if (lab->unremovable) break;
-		unref_counts[lab->label_no]++;
-	    }
-	}
-	else if (IS_LABEL(i)) {
-	    lab = (LABEL *)i;
-	    if (lab->unremovable) return 0;
-	    if (lab->refcnt > unref_counts[lab->label_no]) {
-		if (i == first) return 0;
-		break;
-	    }
-	    continue;
-	}
-	else if (IS_TRACE(i)) {
-	    /* do nothing */
-	}
-	else if (IS_ADJUST(i)) {
-	    LABEL *dest = ((ADJUST *)i)->label;
-	    if (dest && dest->unremovable) return 0;
-	}
-	end = i;
+        LABEL *lab;
+        if (IS_INSN(i)) {
+            if (IS_INSN_ID(i, leave)) {
+                end = i;
+                break;
+            }
+            else if ((lab = find_destination((INSN *)i)) != 0) {
+                unref_counts[lab->label_no]++;
+            }
+        }
+        else if (IS_LABEL(i)) {
+            lab = (LABEL *)i;
+            if (lab->unremovable) return 0;
+            if (lab->refcnt > unref_counts[lab->label_no]) {
+                if (i == first) return 0;
+                break;
+            }
+            continue;
+        }
+        else if (IS_TRACE(i)) {
+            /* do nothing */
+        }
+        else if (IS_ADJUST(i)) {
+            return 0;
+        }
+        end = i;
     } while ((i = i->next) != 0);
     i = first;
     do {
-	if (IS_INSN(i)) {
+        if (IS_INSN(i)) {
             struct rb_iseq_constant_body *body = ISEQ_BODY(iseq);
-	    VALUE insn = INSN_OF(i);
-	    int pos, len = insn_len(insn);
-	    for (pos = 0; pos < len; ++pos) {
-		switch (insn_op_types(insn)[pos]) {
-		  case TS_OFFSET:
-		    unref_destination((INSN *)i, pos);
-		    break;
+            VALUE insn = INSN_OF(i);
+            int pos, len = insn_len(insn);
+            for (pos = 0; pos < len; ++pos) {
+                switch (insn_op_types(insn)[pos]) {
+                  case TS_OFFSET:
+                    unref_destination((INSN *)i, pos);
+                    break;
                   case TS_CALLDATA:
                     --(body->ci_size);
-		    break;
-		}
-	    }
-	}
-	ELEM_REMOVE(i);
+                    break;
+                }
+            }
+        }
+        ELEM_REMOVE(i);
     } while ((i != end) && (i = i->next) != 0);
     return 1;
 }
@@ -2766,14 +2887,14 @@ iseq_pop_newarray(rb_iseq_t *iseq, INSN *iobj)
 {
     switch (OPERAND_AT(iobj, 0)) {
       case INT2FIX(0): /* empty array */
-	ELEM_REMOVE(&iobj->link);
-	return TRUE;
+        ELEM_REMOVE(&iobj->link);
+        return TRUE;
       case INT2FIX(1): /* single element array */
-	ELEM_REMOVE(&iobj->link);
-	return FALSE;
+        ELEM_REMOVE(&iobj->link);
+        return FALSE;
       default:
-	iobj->insn_id = BIN(adjuststack);
-	return TRUE;
+        iobj->insn_id = BIN(adjuststack);
+        return TRUE;
     }
 }
 
@@ -2822,41 +2943,41 @@ optimize_checktype(rb_iseq_t *iseq, INSN *iobj)
 
     switch (INSN_OF(iobj)) {
       case BIN(putstring):
-	type = INT2FIX(T_STRING);
-	break;
+        type = INT2FIX(T_STRING);
+        break;
       case BIN(putnil):
-	type = INT2FIX(T_NIL);
-	break;
+        type = INT2FIX(T_NIL);
+        break;
       case BIN(putobject):
-	type = INT2FIX(TYPE(OPERAND_AT(iobj, 0)));
-	break;
+        type = INT2FIX(TYPE(OPERAND_AT(iobj, 0)));
+        break;
       default: return FALSE;
     }
 
     ciobj = (INSN *)get_next_insn(iobj);
     if (IS_INSN_ID(ciobj, jump)) {
-	ciobj = (INSN *)get_next_insn((INSN*)OPERAND_AT(ciobj, 0));
+        ciobj = (INSN *)get_next_insn((INSN*)OPERAND_AT(ciobj, 0));
     }
     if (IS_INSN_ID(ciobj, dup)) {
-	ciobj = (INSN *)get_next_insn(dup = ciobj);
+        ciobj = (INSN *)get_next_insn(dup = ciobj);
     }
     if (!ciobj || !IS_INSN_ID(ciobj, checktype)) return FALSE;
     niobj = (INSN *)get_next_insn(ciobj);
     if (!niobj) {
-	/* TODO: putobject true/false */
-	return FALSE;
+        /* TODO: putobject true/false */
+        return FALSE;
     }
     switch (INSN_OF(niobj)) {
       case BIN(branchif):
-	if (OPERAND_AT(ciobj, 0) == type) {
-	    dest = (LABEL *)OPERAND_AT(niobj, 0);
-	}
-	break;
+        if (OPERAND_AT(ciobj, 0) == type) {
+            dest = (LABEL *)OPERAND_AT(niobj, 0);
+        }
+        break;
       case BIN(branchunless):
-	if (OPERAND_AT(ciobj, 0) != type) {
-	    dest = (LABEL *)OPERAND_AT(niobj, 0);
-	}
-	break;
+        if (OPERAND_AT(ciobj, 0) != type) {
+            dest = (LABEL *)OPERAND_AT(niobj, 0);
+        }
+        break;
       default:
         return FALSE;
     }
@@ -2864,13 +2985,13 @@ optimize_checktype(rb_iseq_t *iseq, INSN *iobj)
     node_id = ciobj->insn_info.node_id;
     NODE dummy_line_node = generate_dummy_line_node(line, node_id);
     if (!dest) {
-	if (niobj->link.next && IS_LABEL(niobj->link.next)) {
-	    dest = (LABEL *)niobj->link.next; /* reuse label */
-	}
-	else {
-	    dest = NEW_LABEL(line);
-	    ELEM_INSERT_NEXT(&niobj->link, &dest->link);
-	}
+        if (niobj->link.next && IS_LABEL(niobj->link.next)) {
+            dest = (LABEL *)niobj->link.next; /* reuse label */
+        }
+        else {
+            dest = NEW_LABEL(line);
+            ELEM_INSERT_NEXT(&niobj->link, &dest->link);
+        }
     }
     INSERT_AFTER_INSN1(iobj, &dummy_line_node, jump, dest);
     LABEL_REF(dest);
@@ -2910,112 +3031,112 @@ iseq_peephole_optimize(rb_iseq_t *iseq, LINK_ELEMENT *list, const int do_tailcal
 
     if (IS_INSN_ID(iobj, jump)) {
         INSN *niobj, *diobj, *piobj;
-	diobj = (INSN *)get_destination_insn(iobj);
-	niobj = (INSN *)get_next_insn(iobj);
-
-	if (diobj == niobj) {
-	    /*
-	     *   jump LABEL
-	     *  LABEL:
-	     * =>
-	     *   LABEL:
-	     */
-	    unref_destination(iobj, 0);
-	    ELEM_REMOVE(&iobj->link);
-	    return COMPILE_OK;
-	}
+        diobj = (INSN *)get_destination_insn(iobj);
+        niobj = (INSN *)get_next_insn(iobj);
+
+        if (diobj == niobj) {
+            /*
+             *   jump LABEL
+             *  LABEL:
+             * =>
+             *   LABEL:
+             */
+            unref_destination(iobj, 0);
+            ELEM_REMOVE(&iobj->link);
+            return COMPILE_OK;
+        }
         else if (iobj != diobj && IS_INSN(&diobj->link) &&
                  IS_INSN_ID(diobj, jump) &&
-		 OPERAND_AT(iobj, 0) != OPERAND_AT(diobj, 0) &&
+                 OPERAND_AT(iobj, 0) != OPERAND_AT(diobj, 0) &&
                  diobj->insn_info.events == 0) {
-	    /*
-	     *  useless jump elimination:
-	     *     jump LABEL1
-	     *     ...
-	     *   LABEL1:
-	     *     jump LABEL2
-	     *
-	     *   => in this case, first jump instruction should jump to
-	     *      LABEL2 directly
-	     */
-	    replace_destination(iobj, diobj);
-	    remove_unreachable_chunk(iseq, iobj->link.next);
-	    goto again;
-	}
+            /*
+             *  useless jump elimination:
+             *     jump LABEL1
+             *     ...
+             *   LABEL1:
+             *     jump LABEL2
+             *
+             *   => in this case, first jump instruction should jump to
+             *      LABEL2 directly
+             */
+            replace_destination(iobj, diobj);
+            remove_unreachable_chunk(iseq, iobj->link.next);
+            goto again;
+        }
         else if (IS_INSN_ID(diobj, leave)) {
-	    /*
-	     *  jump LABEL
-	     *  ...
-	     * LABEL:
-	     *  leave
-	     * =>
-	     *  leave
-	     *  ...
-	     * LABEL:
-	     *  leave
-	     */
-	    /* replace */
-	    unref_destination(iobj, 0);
+            /*
+             *  jump LABEL
+             *  ...
+             * LABEL:
+             *  leave
+             * =>
+             *  leave
+             *  ...
+             * LABEL:
+             *  leave
+             */
+            /* replace */
+            unref_destination(iobj, 0);
             iobj->insn_id = BIN(leave);
-	    iobj->operand_size = 0;
-	    iobj->insn_info = diobj->insn_info;
-	    goto again;
-	}
+            iobj->operand_size = 0;
+            iobj->insn_info = diobj->insn_info;
+            goto again;
+        }
         else if (IS_INSN(iobj->link.prev) &&
                  (piobj = (INSN *)iobj->link.prev) &&
-		 (IS_INSN_ID(piobj, branchif) ||
-		  IS_INSN_ID(piobj, branchunless))) {
-	    INSN *pdiobj = (INSN *)get_destination_insn(piobj);
-	    if (niobj == pdiobj) {
-		int refcnt = IS_LABEL(piobj->link.next) ?
-		    ((LABEL *)piobj->link.next)->refcnt : 0;
-		/*
-		 * useless jump elimination (if/unless destination):
-		 *   if   L1
-		 *   jump L2
-		 * L1:
-		 *   ...
-		 * L2:
-		 *
-		 * ==>
-		 *   unless L2
-		 * L1:
-		 *   ...
-		 * L2:
-		 */
-		piobj->insn_id = (IS_INSN_ID(piobj, branchif))
-		  ? BIN(branchunless) : BIN(branchif);
-		replace_destination(piobj, iobj);
-		if (refcnt <= 1) {
-		    ELEM_REMOVE(&iobj->link);
-		}
-		else {
-		    /* TODO: replace other branch destinations too */
-		}
-		return COMPILE_OK;
-	    }
-	    else if (diobj == pdiobj) {
-		/*
-		 * useless jump elimination (if/unless before jump):
-		 * L1:
-		 *   ...
-		 *   if   L1
-		 *   jump L1
-		 *
-		 * ==>
-		 * L1:
-		 *   ...
-		 *   pop
-		 *   jump L1
-		 */
+                 (IS_INSN_ID(piobj, branchif) ||
+                  IS_INSN_ID(piobj, branchunless))) {
+            INSN *pdiobj = (INSN *)get_destination_insn(piobj);
+            if (niobj == pdiobj) {
+                int refcnt = IS_LABEL(piobj->link.next) ?
+                    ((LABEL *)piobj->link.next)->refcnt : 0;
+                /*
+                 * useless jump elimination (if/unless destination):
+                 *   if   L1
+                 *   jump L2
+                 * L1:
+                 *   ...
+                 * L2:
+                 *
+                 * ==>
+                 *   unless L2
+                 * L1:
+                 *   ...
+                 * L2:
+                 */
+                piobj->insn_id = (IS_INSN_ID(piobj, branchif))
+                  ? BIN(branchunless) : BIN(branchif);
+                replace_destination(piobj, iobj);
+                if (refcnt <= 1) {
+                    ELEM_REMOVE(&iobj->link);
+                }
+                else {
+                    /* TODO: replace other branch destinations too */
+                }
+                return COMPILE_OK;
+            }
+            else if (diobj == pdiobj) {
+                /*
+                 * useless jump elimination (if/unless before jump):
+                 * L1:
+                 *   ...
+                 *   if   L1
+                 *   jump L1
+                 *
+                 * ==>
+                 * L1:
+                 *   ...
+                 *   pop
+                 *   jump L1
+                 */
                 NODE dummy_line_node = generate_dummy_line_node(iobj->insn_info.line_no, iobj->insn_info.node_id);
-		INSN *popiobj = new_insn_core(iseq, &dummy_line_node, BIN(pop), 0, 0);
-		ELEM_REPLACE(&piobj->link, &popiobj->link);
-	    }
-	}
-	if (remove_unreachable_chunk(iseq, iobj->link.next)) {
-	    goto again;
-	}
+                INSN *popiobj = new_insn_core(iseq, &dummy_line_node, BIN(pop), 0, 0);
+                ELEM_REPLACE(&piobj->link, &popiobj->link);
+            }
+        }
+        if (remove_unreachable_chunk(iseq, iobj->link.next)) {
+            goto again;
+        }
     }
 
     /*
@@ -3036,19 +3157,19 @@ iseq_peephole_optimize(rb_iseq_t *iseq, LINK_ELEMENT *list, const int do_tailcal
                 is_frozen_putstring(end, &str_end) &&
                 (beg = (INSN *)get_prev_insn(end)) != 0 &&
                 is_frozen_putstring(beg, &str_beg)) {
-	    int excl = FIX2INT(OPERAND_AT(range, 0));
-	    VALUE lit_range = rb_range_new(str_beg, str_end, excl);
-
-	    ELEM_REMOVE(&beg->link);
-	    ELEM_REMOVE(&end->link);
-	    range->insn_id = BIN(putobject);
-	    OPERAND_AT(range, 0) = lit_range;
-	    RB_OBJ_WRITTEN(iseq, Qundef, lit_range);
-	}
+            int excl = FIX2INT(OPERAND_AT(range, 0));
+            VALUE lit_range = rb_range_new(str_beg, str_end, excl);
+
+            ELEM_REMOVE(&beg->link);
+            ELEM_REMOVE(&end->link);
+            range->insn_id = BIN(putobject);
+            OPERAND_AT(range, 0) = lit_range;
+            RB_OBJ_WRITTEN(iseq, Qundef, lit_range);
+        }
     }
 
     if (IS_INSN_ID(iobj, leave)) {
-	remove_unreachable_chunk(iseq, iobj->link.next);
+        remove_unreachable_chunk(iseq, iobj->link.next);
     }
 
     /*
@@ -3068,17 +3189,17 @@ iseq_peephole_optimize(rb_iseq_t *iseq, LINK_ELEMENT *list, const int do_tailcal
     }
 
     if (IS_INSN_ID(iobj, branchif) ||
-	IS_INSN_ID(iobj, branchnil) ||
-	IS_INSN_ID(iobj, branchunless)) {
-	/*
-	 *   if L1
-	 *   ...
-	 * L1:
-	 *   jump L2
-	 * =>
-	 *   if L2
-	 */
-	INSN *nobj = (INSN *)get_destination_insn(iobj);
+        IS_INSN_ID(iobj, branchnil) ||
+        IS_INSN_ID(iobj, branchunless)) {
+        /*
+         *   if L1
+         *   ...
+         * L1:
+         *   jump L2
+         * =>
+         *   if L2
+         */
+        INSN *nobj = (INSN *)get_destination_insn(iobj);
 
         /* This is super nasty hack!!!
          *
@@ -3101,10 +3222,10 @@ iseq_peephole_optimize(rb_iseq_t *iseq, LINK_ELEMENT *list, const int do_tailcal
          * This should be fixed in future.
          */
         int stop_optimization =
-	    ISEQ_COVERAGE(iseq) && ISEQ_LINE_COVERAGE(iseq) &&
+            ISEQ_COVERAGE(iseq) && ISEQ_LINE_COVERAGE(iseq) &&
             nobj->link.type == ISEQ_ELEMENT_INSN &&
             nobj->insn_info.events;
-	if (!stop_optimization) {
+        if (!stop_optimization) {
             INSN *pobj = (INSN *)iobj->link.prev;
             int prev_dup = 0;
             if (pobj) {
@@ -3214,231 +3335,344 @@ iseq_peephole_optimize(rb_iseq_t *iseq, LINK_ELEMENT *list, const int do_tailcal
     }
 
     if (IS_INSN_ID(iobj, pop)) {
-	/*
-	 *  putself / putnil / putobject obj / putstring "..."
-	 *  pop
-	 * =>
-	 *  # do nothing
-	 */
-	LINK_ELEMENT *prev = iobj->link.prev;
-	if (IS_INSN(prev)) {
-	    enum ruby_vminsn_type previ = ((INSN *)prev)->insn_id;
-	    if (previ == BIN(putobject) || previ == BIN(putnil) ||
-		previ == BIN(putself) || previ == BIN(putstring) ||
-		previ == BIN(dup) ||
-		previ == BIN(getlocal) ||
-		previ == BIN(getblockparam) ||
-		previ == BIN(getblockparamproxy) ||
-		/* getinstancevariable may issue a warning */
-		previ == BIN(duparray)) {
-		/* just push operand or static value and pop soon, no
-		 * side effects */
-		ELEM_REMOVE(prev);
-		ELEM_REMOVE(&iobj->link);
-	    }
-	    else if (previ == BIN(newarray) && iseq_pop_newarray(iseq, (INSN*)prev)) {
-		ELEM_REMOVE(&iobj->link);
-	    }
-	    else if (previ == BIN(concatarray)) {
-		INSN *piobj = (INSN *)prev;
+        /*
+         *  putself / putnil / putobject obj / putstring "..."
+         *  pop
+         * =>
+         *  # do nothing
+         */
+        LINK_ELEMENT *prev = iobj->link.prev;
+        if (IS_INSN(prev)) {
+            enum ruby_vminsn_type previ = ((INSN *)prev)->insn_id;
+            if (previ == BIN(putobject) || previ == BIN(putnil) ||
+                previ == BIN(putself) || previ == BIN(putstring) ||
+                previ == BIN(dup) ||
+                previ == BIN(getlocal) ||
+                previ == BIN(getblockparam) ||
+                previ == BIN(getblockparamproxy) ||
+                /* getinstancevariable may issue a warning */
+                previ == BIN(duparray)) {
+                /* just push operand or static value and pop soon, no
+                 * side effects */
+                ELEM_REMOVE(prev);
+                ELEM_REMOVE(&iobj->link);
+            }
+            else if (previ == BIN(newarray) && iseq_pop_newarray(iseq, (INSN*)prev)) {
+                ELEM_REMOVE(&iobj->link);
+            }
+            else if (previ == BIN(concatarray)) {
+                INSN *piobj = (INSN *)prev;
                 NODE dummy_line_node = generate_dummy_line_node(piobj->insn_info.line_no, piobj->insn_info.node_id);
-		INSERT_BEFORE_INSN1(piobj, &dummy_line_node, splatarray, Qfalse);
-		INSN_OF(piobj) = BIN(pop);
-	    }
-	    else if (previ == BIN(concatstrings)) {
-		if (OPERAND_AT(prev, 0) == INT2FIX(1)) {
-		    ELEM_REMOVE(prev);
-		}
-		else {
-		    ELEM_REMOVE(&iobj->link);
-		    INSN_OF(prev) = BIN(adjuststack);
-		}
-	    }
-	}
+                INSERT_BEFORE_INSN1(piobj, &dummy_line_node, splatarray, Qfalse);
+                INSN_OF(piobj) = BIN(pop);
+            }
+            else if (previ == BIN(concatstrings)) {
+                if (OPERAND_AT(prev, 0) == INT2FIX(1)) {
+                    ELEM_REMOVE(prev);
+                }
+                else {
+                    ELEM_REMOVE(&iobj->link);
+                    INSN_OF(prev) = BIN(adjuststack);
+                }
+            }
+        }
     }
 
     if (IS_INSN_ID(iobj, newarray) ||
-	IS_INSN_ID(iobj, duparray) ||
-	IS_INSN_ID(iobj, expandarray) ||
-	IS_INSN_ID(iobj, concatarray) ||
-	IS_INSN_ID(iobj, splatarray) ||
-	0) {
-	/*
-	 *  newarray N
-	 *  splatarray
-	 * =>
-	 *  newarray N
-	 * newarray always puts an array
-	 */
-	LINK_ELEMENT *next = iobj->link.next;
-	if (IS_INSN(next) && IS_INSN_ID(next, splatarray)) {
-	    /* remove splatarray following always-array insn */
-	    ELEM_REMOVE(next);
-	}
+        IS_INSN_ID(iobj, duparray) ||
+        IS_INSN_ID(iobj, expandarray) ||
+        IS_INSN_ID(iobj, concatarray) ||
+        IS_INSN_ID(iobj, splatarray) ||
+        0) {
+        /*
+         *  newarray N
+         *  splatarray
+         * =>
+         *  newarray N
+         * newarray always puts an array
+         */
+        LINK_ELEMENT *next = iobj->link.next;
+        if (IS_INSN(next) && IS_INSN_ID(next, splatarray)) {
+            /* remove splatarray following always-array insn */
+            ELEM_REMOVE(next);
+        }
+    }
+
+    if (IS_INSN_ID(iobj, newarray)) {
+        LINK_ELEMENT *next = iobj->link.next;
+        if (IS_INSN(next) && IS_INSN_ID(next, expandarray) &&
+            OPERAND_AT(next, 1) == INT2FIX(0)) {
+            VALUE op1, op2;
+            op1 = OPERAND_AT(iobj, 0);
+            op2 = OPERAND_AT(next, 0);
+            ELEM_REMOVE(next);
+
+            if (op1 == op2) {
+                /*
+                 *  newarray 2
+                 *  expandarray 2, 0
+                 * =>
+                 *  swap
+                 */
+                if (op1 == INT2FIX(2)) {
+                    INSN_OF(iobj) = BIN(swap);
+                    iobj->operand_size = 0;
+                }
+                /*
+                 *  newarray X
+                 *  expandarray X, 0
+                 * =>
+                 *  opt_reverse X
+                 */
+                else {
+                    INSN_OF(iobj) = BIN(opt_reverse);
+                }
+            }
+            else {
+                NODE dummy_line_node = generate_dummy_line_node(iobj->insn_info.line_no, iobj->insn_info.node_id);
+                long diff = FIX2LONG(op1) - FIX2LONG(op2);
+                INSN_OF(iobj) = BIN(opt_reverse);
+                OPERAND_AT(iobj, 0) = OPERAND_AT(next, 0);
+
+                if (op1 > op2) {
+                    /* X > Y
+                     *  newarray X
+                     *  expandarray Y, 0
+                     * =>
+                     *  pop * (Y-X)
+                     *  opt_reverse Y
+                     */
+                    for (; diff > 0; diff--) {
+                        INSERT_BEFORE_INSN(iobj, &dummy_line_node, pop);
+                    }
+                }
+                else { /* (op1 < op2) */
+                    /* X < Y
+                     *  newarray X
+                     *  expandarray Y, 0
+                     * =>
+                     *  putnil * (Y-X)
+                     *  opt_reverse Y
+                     */
+                    for (; diff < 0; diff++) {
+                        INSERT_BEFORE_INSN(iobj, &dummy_line_node, putnil);
+                    }
+                }
+            }
+        }
+    }
+
+    if (IS_INSN_ID(iobj, duparray)) {
+        LINK_ELEMENT *next = iobj->link.next;
+        /*
+         *  duparray obj
+         *  expandarray X, 0
+         * =>
+         *  putobject obj
+         *  expandarray X, 0
+         */
+        if (IS_INSN(next) && IS_INSN_ID(next, expandarray)) {
+            INSN_OF(iobj) = BIN(putobject);
+        }
     }
 
     if (IS_INSN_ID(iobj, anytostring)) {
-	LINK_ELEMENT *next = iobj->link.next;
-	/*
+        LINK_ELEMENT *next = iobj->link.next;
+        /*
          *  anytostring
-	 *  concatstrings 1
-	 * =>
+         *  concatstrings 1
+         * =>
          *  anytostring
-	 */
-	if (IS_INSN(next) && IS_INSN_ID(next, concatstrings) &&
-	    OPERAND_AT(next, 0) == INT2FIX(1)) {
-	    ELEM_REMOVE(next);
-	}
+         */
+        if (IS_INSN(next) && IS_INSN_ID(next, concatstrings) &&
+            OPERAND_AT(next, 0) == INT2FIX(1)) {
+            ELEM_REMOVE(next);
+        }
     }
 
     if (IS_INSN_ID(iobj, putstring) ||
-	(IS_INSN_ID(iobj, putobject) && RB_TYPE_P(OPERAND_AT(iobj, 0), T_STRING))) {
-	/*
-	 *  putstring ""
-	 *  concatstrings N
-	 * =>
-	 *  concatstrings N-1
-	 */
-	if (IS_NEXT_INSN_ID(&iobj->link, concatstrings) &&
-	    RSTRING_LEN(OPERAND_AT(iobj, 0)) == 0) {
-	    INSN *next = (INSN *)iobj->link.next;
-	    if ((OPERAND_AT(next, 0) = FIXNUM_INC(OPERAND_AT(next, 0), -1)) == INT2FIX(1)) {
-		ELEM_REMOVE(&next->link);
-	    }
-	    ELEM_REMOVE(&iobj->link);
-	}
+        (IS_INSN_ID(iobj, putobject) && RB_TYPE_P(OPERAND_AT(iobj, 0), T_STRING))) {
+        /*
+         *  putstring ""
+         *  concatstrings N
+         * =>
+         *  concatstrings N-1
+         */
+        if (IS_NEXT_INSN_ID(&iobj->link, concatstrings) &&
+            RSTRING_LEN(OPERAND_AT(iobj, 0)) == 0) {
+            INSN *next = (INSN *)iobj->link.next;
+            if ((OPERAND_AT(next, 0) = FIXNUM_INC(OPERAND_AT(next, 0), -1)) == INT2FIX(1)) {
+                ELEM_REMOVE(&next->link);
+            }
+            ELEM_REMOVE(&iobj->link);
+        }
     }
 
     if (IS_INSN_ID(iobj, concatstrings)) {
-	/*
-	 *  concatstrings N
-	 *  concatstrings M
-	 * =>
-	 *  concatstrings N+M-1
-	 */
-	LINK_ELEMENT *next = iobj->link.next;
-	INSN *jump = 0;
-	if (IS_INSN(next) && IS_INSN_ID(next, jump))
-	    next = get_destination_insn(jump = (INSN *)next);
-	if (IS_INSN(next) && IS_INSN_ID(next, concatstrings)) {
-	    int n = FIX2INT(OPERAND_AT(iobj, 0)) + FIX2INT(OPERAND_AT(next, 0)) - 1;
-	    OPERAND_AT(iobj, 0) = INT2FIX(n);
-	    if (jump) {
-		LABEL *label = ((LABEL *)OPERAND_AT(jump, 0));
-		if (!--label->refcnt) {
-		    ELEM_REMOVE(&label->link);
-		}
-		else {
-		    label = NEW_LABEL(0);
-		    OPERAND_AT(jump, 0) = (VALUE)label;
-		}
-		label->refcnt++;
-		ELEM_INSERT_NEXT(next, &label->link);
-		CHECK(iseq_peephole_optimize(iseq, get_next_insn(jump), do_tailcallopt));
-	    }
-	    else {
-		ELEM_REMOVE(next);
-	    }
-	}
+        /*
+         *  concatstrings N
+         *  concatstrings M
+         * =>
+         *  concatstrings N+M-1
+         */
+        LINK_ELEMENT *next = iobj->link.next;
+        INSN *jump = 0;
+        if (IS_INSN(next) && IS_INSN_ID(next, jump))
+            next = get_destination_insn(jump = (INSN *)next);
+        if (IS_INSN(next) && IS_INSN_ID(next, concatstrings)) {
+            int n = FIX2INT(OPERAND_AT(iobj, 0)) + FIX2INT(OPERAND_AT(next, 0)) - 1;
+            OPERAND_AT(iobj, 0) = INT2FIX(n);
+            if (jump) {
+                LABEL *label = ((LABEL *)OPERAND_AT(jump, 0));
+                if (!--label->refcnt) {
+                    ELEM_REMOVE(&label->link);
+                }
+                else {
+                    label = NEW_LABEL(0);
+                    OPERAND_AT(jump, 0) = (VALUE)label;
+                }
+                label->refcnt++;
+                ELEM_INSERT_NEXT(next, &label->link);
+                CHECK(iseq_peephole_optimize(iseq, get_next_insn(jump), do_tailcallopt));
+            }
+            else {
+                ELEM_REMOVE(next);
+            }
+        }
     }
 
     if (do_tailcallopt &&
-	(IS_INSN_ID(iobj, send) ||
-	 IS_INSN_ID(iobj, opt_aref_with) ||
-	 IS_INSN_ID(iobj, opt_aset_with) ||
-	 IS_INSN_ID(iobj, invokesuper))) {
-	/*
-	 *  send ...
-	 *  leave
-	 * =>
-	 *  send ..., ... | VM_CALL_TAILCALL, ...
-	 *  leave # unreachable
-	 */
-	INSN *piobj = NULL;
-	if (iobj->link.next) {
-	    LINK_ELEMENT *next = iobj->link.next;
-	    do {
-		if (!IS_INSN(next)) {
-		    next = next->next;
-		    continue;
-		}
-		switch (INSN_OF(next)) {
-		  case BIN(nop):
-		    next = next->next;
-		    break;
-		  case BIN(jump):
-		    /* if cond
-		     *   return tailcall
-		     * end
-		     */
-		    next = get_destination_insn((INSN *)next);
-		    break;
-		  case BIN(leave):
-		    piobj = iobj;
+        (IS_INSN_ID(iobj, send) ||
+         IS_INSN_ID(iobj, opt_aref_with) ||
+         IS_INSN_ID(iobj, opt_aset_with) ||
+         IS_INSN_ID(iobj, invokesuper))) {
+        /*
+         *  send ...
+         *  leave
+         * =>
+         *  send ..., ... | VM_CALL_TAILCALL, ...
+         *  leave # unreachable
+         */
+        INSN *piobj = NULL;
+        if (iobj->link.next) {
+            LINK_ELEMENT *next = iobj->link.next;
+            do {
+                if (!IS_INSN(next)) {
+                    next = next->next;
+                    continue;
+                }
+                switch (INSN_OF(next)) {
+                  case BIN(nop):
+                    next = next->next;
+                    break;
+                  case BIN(jump):
+                    /* if cond
+                     *   return tailcall
+                     * end
+                     */
+                    next = get_destination_insn((INSN *)next);
+                    break;
+                  case BIN(leave):
+                    piobj = iobj;
                     /* fall through */
-		  default:
-		    next = NULL;
-		    break;
-		}
-	    } while (next);
-	}
-
-	if (piobj) {
+                  default:
+                    next = NULL;
+                    break;
+                }
+            } while (next);
+        }
+
+        if (piobj) {
             const struct rb_callinfo *ci = (struct rb_callinfo *)OPERAND_AT(piobj, 0);
-	    if (IS_INSN_ID(piobj, send) ||
+            if (IS_INSN_ID(piobj, send) ||
                 IS_INSN_ID(piobj, invokesuper)) {
                 if (OPERAND_AT(piobj, 1) == 0) { /* no blockiseq */
                     ci = ci_flag_set(iseq, ci, VM_CALL_TAILCALL);
                     OPERAND_AT(piobj, 0) = (VALUE)ci;
                     RB_OBJ_WRITTEN(iseq, Qundef, ci);
-		}
-	    }
-	    else {
+                }
+            }
+            else {
                 ci = ci_flag_set(iseq, ci, VM_CALL_TAILCALL);
                 OPERAND_AT(piobj, 0) = (VALUE)ci;
                 RB_OBJ_WRITTEN(iseq, Qundef, ci);
-	    }
-	}
+            }
+        }
     }
 
     if (IS_INSN_ID(iobj, dup)) {
-	if (IS_NEXT_INSN_ID(&iobj->link, setlocal)) {
-	    LINK_ELEMENT *set1 = iobj->link.next, *set2 = NULL;
-	    if (IS_NEXT_INSN_ID(set1, setlocal)) {
-		set2 = set1->next;
-		if (OPERAND_AT(set1, 0) == OPERAND_AT(set2, 0) &&
-		    OPERAND_AT(set1, 1) == OPERAND_AT(set2, 1)) {
-		    ELEM_REMOVE(set1);
-		    ELEM_REMOVE(&iobj->link);
-		}
-	    }
-	    else if (IS_NEXT_INSN_ID(set1, dup) &&
-		     IS_NEXT_INSN_ID(set1->next, setlocal)) {
-		set2 = set1->next->next;
-		if (OPERAND_AT(set1, 0) == OPERAND_AT(set2, 0) &&
-		    OPERAND_AT(set1, 1) == OPERAND_AT(set2, 1)) {
-		    ELEM_REMOVE(set1->next);
-		    ELEM_REMOVE(set2);
-		}
-	    }
-	}
+        if (IS_NEXT_INSN_ID(&iobj->link, setlocal)) {
+            LINK_ELEMENT *set1 = iobj->link.next, *set2 = NULL;
+
+            /*
+            *  dup
+            *  setlocal x, y
+            *  setlocal x, y
+            * =>
+            *  dup
+            *  setlocal x, y
+            */
+            if (IS_NEXT_INSN_ID(set1, setlocal)) {
+                set2 = set1->next;
+                if (OPERAND_AT(set1, 0) == OPERAND_AT(set2, 0) &&
+                    OPERAND_AT(set1, 1) == OPERAND_AT(set2, 1)) {
+                    ELEM_REMOVE(set1);
+                    ELEM_REMOVE(&iobj->link);
+                }
+            }
+
+            /*
+            *  dup
+            *  setlocal x, y
+            *  dup
+            *  setlocal x, y
+            * =>
+            *  dup
+            *  setlocal x, y
+            */
+            else if (IS_NEXT_INSN_ID(set1, dup) &&
+                     IS_NEXT_INSN_ID(set1->next, setlocal)) {
+                set2 = set1->next->next;
+                if (OPERAND_AT(set1, 0) == OPERAND_AT(set2, 0) &&
+                    OPERAND_AT(set1, 1) == OPERAND_AT(set2, 1)) {
+                    ELEM_REMOVE(set1->next);
+                    ELEM_REMOVE(set2);
+                }
+            }
+        }
     }
 
+    /*
+    *  getlocal x, y
+    *  dup
+    *  setlocal x, y
+    * =>
+    *  dup
+    */
     if (IS_INSN_ID(iobj, getlocal)) {
-	LINK_ELEMENT *niobj = &iobj->link;
-	if (IS_NEXT_INSN_ID(niobj, dup)) {
-	    niobj = niobj->next;
-	}
-	if (IS_NEXT_INSN_ID(niobj, setlocal)) {
-	    LINK_ELEMENT *set1 = niobj->next;
-	    if (OPERAND_AT(iobj, 0) == OPERAND_AT(set1, 0) &&
-		OPERAND_AT(iobj, 1) == OPERAND_AT(set1, 1)) {
-		ELEM_REMOVE(set1);
-		ELEM_REMOVE(niobj);
-	    }
-	}
+        LINK_ELEMENT *niobj = &iobj->link;
+        if (IS_NEXT_INSN_ID(niobj, dup)) {
+            niobj = niobj->next;
+        }
+        if (IS_NEXT_INSN_ID(niobj, setlocal)) {
+            LINK_ELEMENT *set1 = niobj->next;
+            if (OPERAND_AT(iobj, 0) == OPERAND_AT(set1, 0) &&
+                OPERAND_AT(iobj, 1) == OPERAND_AT(set1, 1)) {
+                ELEM_REMOVE(set1);
+                ELEM_REMOVE(niobj);
+            }
+        }
     }
 
+    /*
+    *  opt_invokebuiltin_delegate
+    *  trace
+    *  leave
+    * =>
+    *  opt_invokebuiltin_delegate_leave
+    *  trace
+    *  leave
+    */
     if (IS_INSN_ID(iobj, opt_invokebuiltin_delegate)) {
         if (IS_TRACE(iobj->link.next)) {
             if (IS_NEXT_INSN_ID(iobj->link.next, leave)) {
@@ -3447,6 +3681,19 @@ iseq_peephole_optimize(rb_iseq_t *iseq, LINK_ELEMENT *list, const int do_tailcal
         }
     }
 
+    /*
+    *  getblockparam
+    *  branchif / branchunless
+    * =>
+    *  getblockparamproxy
+    *  branchif / branchunless
+    */
+    if (IS_INSN_ID(iobj, getblockparam)) {
+        if (IS_NEXT_INSN_ID(&iobj->link, branchif) || IS_NEXT_INSN_ID(&iobj->link, branchunless)) {
+            iobj->insn_id = BIN(getblockparamproxy);
+        }
+    }
+
     return COMPILE_OK;
 }
 
@@ -3472,26 +3719,26 @@ static int
 iseq_specialized_instruction(rb_iseq_t *iseq, INSN *iobj)
 {
     if (IS_INSN_ID(iobj, newarray) && iobj->link.next &&
-	IS_INSN(iobj->link.next)) {
-	/*
-	 *   [a, b, ...].max/min -> a, b, c, opt_newarray_max/min
-	 */
-	INSN *niobj = (INSN *)iobj->link.next;
-	if (IS_INSN_ID(niobj, send)) {
+        IS_INSN(iobj->link.next)) {
+        /*
+         *   [a, b, ...].max/min -> a, b, c, opt_newarray_max/min
+         */
+        INSN *niobj = (INSN *)iobj->link.next;
+        if (IS_INSN_ID(niobj, send)) {
             const struct rb_callinfo *ci = (struct rb_callinfo *)OPERAND_AT(niobj, 0);
             if ((vm_ci_flag(ci) & VM_CALL_ARGS_SIMPLE) && vm_ci_argc(ci) == 0) {
-		switch (vm_ci_mid(ci)) {
-		  case idMax:
-		    iobj->insn_id = BIN(opt_newarray_max);
-		    ELEM_REMOVE(&niobj->link);
-		    return COMPILE_OK;
-		  case idMin:
-		    iobj->insn_id = BIN(opt_newarray_min);
-		    ELEM_REMOVE(&niobj->link);
-		    return COMPILE_OK;
-		}
-	    }
-	}
+                switch (vm_ci_mid(ci)) {
+                  case idMax:
+                    iobj->insn_id = BIN(opt_newarray_max);
+                    ELEM_REMOVE(&niobj->link);
+                    return COMPILE_OK;
+                  case idMin:
+                    iobj->insn_id = BIN(opt_newarray_min);
+                    ELEM_REMOVE(&niobj->link);
+                    return COMPILE_OK;
+                }
+            }
+        }
     }
 
     if (IS_INSN_ID(iobj, send)) {
@@ -3499,50 +3746,50 @@ iseq_specialized_instruction(rb_iseq_t *iseq, INSN *iobj)
         const rb_iseq_t *blockiseq = (rb_iseq_t *)OPERAND_AT(iobj, 1);
 
 #define SP_INSN(opt) insn_set_specialized_instruction(iseq, iobj, BIN(opt_##opt))
-	if (vm_ci_flag(ci) & VM_CALL_ARGS_SIMPLE) {
-	    switch (vm_ci_argc(ci)) {
-	      case 0:
-		switch (vm_ci_mid(ci)) {
-		  case idLength: SP_INSN(length); return COMPILE_OK;
-		  case idSize:	 SP_INSN(size);	  return COMPILE_OK;
-		  case idEmptyP: SP_INSN(empty_p);return COMPILE_OK;
+        if (vm_ci_flag(ci) & VM_CALL_ARGS_SIMPLE) {
+            switch (vm_ci_argc(ci)) {
+              case 0:
+                switch (vm_ci_mid(ci)) {
+                  case idLength: SP_INSN(length); return COMPILE_OK;
+                  case idSize:	 SP_INSN(size);	  return COMPILE_OK;
+                  case idEmptyP: SP_INSN(empty_p);return COMPILE_OK;
                   case idNilP:   SP_INSN(nil_p);  return COMPILE_OK;
-		  case idSucc:	 SP_INSN(succ);	  return COMPILE_OK;
-		  case idNot:	 SP_INSN(not);	  return COMPILE_OK;
-		}
-		break;
-	      case 1:
-		switch (vm_ci_mid(ci)) {
-		  case idPLUS:	 SP_INSN(plus);	  return COMPILE_OK;
-		  case idMINUS:	 SP_INSN(minus);  return COMPILE_OK;
-		  case idMULT:	 SP_INSN(mult);	  return COMPILE_OK;
-		  case idDIV:	 SP_INSN(div);	  return COMPILE_OK;
-		  case idMOD:	 SP_INSN(mod);	  return COMPILE_OK;
-		  case idEq:	 SP_INSN(eq);	  return COMPILE_OK;
-		  case idNeq:	 SP_INSN(neq);	  return COMPILE_OK;
-		  case idEqTilde:SP_INSN(regexpmatch2);return COMPILE_OK;
-		  case idLT:	 SP_INSN(lt);	  return COMPILE_OK;
-		  case idLE:	 SP_INSN(le);	  return COMPILE_OK;
-		  case idGT:	 SP_INSN(gt);	  return COMPILE_OK;
-		  case idGE:	 SP_INSN(ge);	  return COMPILE_OK;
-		  case idLTLT:	 SP_INSN(ltlt);	  return COMPILE_OK;
-		  case idAREF:	 SP_INSN(aref);	  return COMPILE_OK;
+                  case idSucc:	 SP_INSN(succ);	  return COMPILE_OK;
+                  case idNot:	 SP_INSN(not);	  return COMPILE_OK;
+                }
+                break;
+              case 1:
+                switch (vm_ci_mid(ci)) {
+                  case idPLUS:	 SP_INSN(plus);	  return COMPILE_OK;
+                  case idMINUS:	 SP_INSN(minus);  return COMPILE_OK;
+                  case idMULT:	 SP_INSN(mult);	  return COMPILE_OK;
+                  case idDIV:	 SP_INSN(div);	  return COMPILE_OK;
+                  case idMOD:	 SP_INSN(mod);	  return COMPILE_OK;
+                  case idEq:	 SP_INSN(eq);	  return COMPILE_OK;
+                  case idNeq:	 SP_INSN(neq);	  return COMPILE_OK;
+                  case idEqTilde:SP_INSN(regexpmatch2);return COMPILE_OK;
+                  case idLT:	 SP_INSN(lt);	  return COMPILE_OK;
+                  case idLE:	 SP_INSN(le);	  return COMPILE_OK;
+                  case idGT:	 SP_INSN(gt);	  return COMPILE_OK;
+                  case idGE:	 SP_INSN(ge);	  return COMPILE_OK;
+                  case idLTLT:	 SP_INSN(ltlt);	  return COMPILE_OK;
+                  case idAREF:	 SP_INSN(aref);	  return COMPILE_OK;
                   case idAnd:    SP_INSN(and);    return COMPILE_OK;
                   case idOr:     SP_INSN(or);    return COMPILE_OK;
-		}
-		break;
-	      case 2:
-		switch (vm_ci_mid(ci)) {
-		  case idASET:	 SP_INSN(aset);	  return COMPILE_OK;
-		}
-		break;
-	    }
-	}
-
-	if ((vm_ci_flag(ci) & VM_CALL_ARGS_BLOCKARG) == 0 && blockiseq == NULL) {
-	    iobj->insn_id = BIN(opt_send_without_block);
-	    iobj->operand_size = insn_len(iobj->insn_id) - 1;
-	}
+                }
+                break;
+              case 2:
+                switch (vm_ci_mid(ci)) {
+                  case idASET:	 SP_INSN(aset);	  return COMPILE_OK;
+                }
+                break;
+            }
+        }
+
+        if ((vm_ci_flag(ci) & VM_CALL_ARGS_BLOCKARG) == 0 && blockiseq == NULL) {
+            iobj->insn_id = BIN(opt_send_without_block);
+            iobj->operand_size = insn_len(iobj->insn_id) - 1;
+        }
     }
 #undef SP_INSN
 
@@ -3556,13 +3803,13 @@ tailcallable_p(rb_iseq_t *iseq)
       case ISEQ_TYPE_TOP:
       case ISEQ_TYPE_EVAL:
       case ISEQ_TYPE_MAIN:
-	/* not tail callable because cfp will be over popped */
+        /* not tail callable because cfp will be over popped */
       case ISEQ_TYPE_RESCUE:
       case ISEQ_TYPE_ENSURE:
-	/* rescue block can't tail call because of errinfo */
-	return FALSE;
+        /* rescue block can't tail call because of errinfo */
+        return FALSE;
       default:
-	return TRUE;
+        return TRUE;
     }
 }
 
@@ -3572,7 +3819,7 @@ iseq_optimize(rb_iseq_t *iseq, LINK_ANCHOR *const anchor)
     LINK_ELEMENT *list;
     const int do_peepholeopt = ISEQ_COMPILE_DATA(iseq)->option->peephole_optimization;
     const int do_tailcallopt = tailcallable_p(iseq) &&
-	ISEQ_COMPILE_DATA(iseq)->option->tailcall_optimization;
+        ISEQ_COMPILE_DATA(iseq)->option->tailcall_optimization;
     const int do_si = ISEQ_COMPILE_DATA(iseq)->option->specialized_instruction;
     const int do_ou = ISEQ_COMPILE_DATA(iseq)->option->operands_unification;
     int rescue_level = 0;
@@ -3587,16 +3834,16 @@ iseq_optimize(rb_iseq_t *iseq, LINK_ANCHOR *const anchor)
     }
 
     while (list) {
-	if (IS_INSN(list)) {
-	    if (do_peepholeopt) {
-		iseq_peephole_optimize(iseq, list, tailcallopt);
-	    }
-	    if (do_si) {
-		iseq_specialized_instruction(iseq, (INSN *)list);
-	    }
-	    if (do_ou) {
-		insn_operands_unification((INSN *)list);
-	    }
+        if (IS_INSN(list)) {
+            if (do_peepholeopt) {
+                iseq_peephole_optimize(iseq, list, tailcallopt);
+            }
+            if (do_si) {
+                iseq_specialized_instruction(iseq, (INSN *)list);
+            }
+            if (do_ou) {
+                insn_operands_unification((INSN *)list);
+            }
 
             if (do_block_optimization) {
                 INSN * item = (INSN *)list;
@@ -3604,19 +3851,19 @@ iseq_optimize(rb_iseq_t *iseq, LINK_ANCHOR *const anchor)
                     do_block_optimization = 0;
                 }
             }
-	}
-	if (IS_LABEL(list)) {
-	    switch (((LABEL *)list)->rescued) {
-	      case LABEL_RESCUE_BEG:
-		rescue_level++;
-		tailcallopt = FALSE;
-		break;
-	      case LABEL_RESCUE_END:
-		if (!--rescue_level) tailcallopt = do_tailcallopt;
-		break;
-	    }
-	}
-	list = list->next;
+        }
+        if (IS_LABEL(list)) {
+            switch (((LABEL *)list)->rescued) {
+              case LABEL_RESCUE_BEG:
+                rescue_level++;
+                tailcallopt = FALSE;
+                break;
+              case LABEL_RESCUE_END:
+                if (!--rescue_level) tailcallopt = do_tailcallopt;
+                break;
+            }
+        }
+        list = list->next;
     }
 
     if (do_block_optimization) {
@@ -3631,7 +3878,7 @@ iseq_optimize(rb_iseq_t *iseq, LINK_ANCHOR *const anchor)
 #if OPT_INSTRUCTIONS_UNIFICATION
 static INSN *
 new_unified_insn(rb_iseq_t *iseq,
-		 int insn_id, int size, LINK_ELEMENT *seq_list)
+                 int insn_id, int size, LINK_ELEMENT *seq_list)
 {
     INSN *iobj = 0;
     LINK_ELEMENT *list = seq_list;
@@ -3641,22 +3888,22 @@ new_unified_insn(rb_iseq_t *iseq,
 
     /* count argc */
     for (i = 0; i < size; i++) {
-	iobj = (INSN *)list;
-	argc += iobj->operand_size;
-	list = list->next;
+        iobj = (INSN *)list;
+        argc += iobj->operand_size;
+        list = list->next;
     }
 
     if (argc > 0) {
-	ptr = operands = compile_data_alloc2(iseq, sizeof(VALUE), argc);
+        ptr = operands = compile_data_alloc2(iseq, sizeof(VALUE), argc);
     }
 
     /* copy operands */
     list = seq_list;
     for (i = 0; i < size; i++) {
-	iobj = (INSN *)list;
-	MEMCPY(ptr, iobj->operands, VALUE, iobj->operand_size);
-	ptr += iobj->operand_size;
-	list = list->next;
+        iobj = (INSN *)list;
+        MEMCPY(ptr, iobj->operands, VALUE, iobj->operand_size);
+        ptr += iobj->operand_size;
+        list = list->next;
     }
 
     NODE dummy_line_node = generate_dummy_line_node(iobj->insn_info.line_no, iobj->insn_info.node_id);
@@ -3680,41 +3927,41 @@ iseq_insns_unification(rb_iseq_t *iseq, LINK_ANCHOR *const anchor)
 
     list = FIRST_ELEMENT(anchor);
     while (list) {
-	if (IS_INSN(list)) {
-	    iobj = (INSN *)list;
-	    id = iobj->insn_id;
-	    if (unified_insns_data[id] != 0) {
-		const int *const *entry = unified_insns_data[id];
-		for (j = 1; j < (intptr_t)entry[0]; j++) {
-		    const int *unified = entry[j];
-		    LINK_ELEMENT *li = list->next;
-		    for (k = 2; k < unified[1]; k++) {
-			if (!IS_INSN(li) ||
-			    ((INSN *)li)->insn_id != unified[k]) {
-			    goto miss;
-			}
-			li = li->next;
-		    }
-		    /* matched */
-		    niobj =
-			new_unified_insn(iseq, unified[0], unified[1] - 1,
-					 list);
-
-		    /* insert to list */
-		    niobj->link.prev = (LINK_ELEMENT *)iobj->link.prev;
-		    niobj->link.next = li;
-		    if (li) {
-			li->prev = (LINK_ELEMENT *)niobj;
-		    }
-
-		    list->prev->next = (LINK_ELEMENT *)niobj;
-		    list = (LINK_ELEMENT *)niobj;
-		    break;
-		  miss:;
-		}
-	    }
-	}
-	list = list->next;
+        if (IS_INSN(list)) {
+            iobj = (INSN *)list;
+            id = iobj->insn_id;
+            if (unified_insns_data[id] != 0) {
+                const int *const *entry = unified_insns_data[id];
+                for (j = 1; j < (intptr_t)entry[0]; j++) {
+                    const int *unified = entry[j];
+                    LINK_ELEMENT *li = list->next;
+                    for (k = 2; k < unified[1]; k++) {
+                        if (!IS_INSN(li) ||
+                            ((INSN *)li)->insn_id != unified[k]) {
+                            goto miss;
+                        }
+                        li = li->next;
+                    }
+                    /* matched */
+                    niobj =
+                        new_unified_insn(iseq, unified[0], unified[1] - 1,
+                                         list);
+
+                    /* insert to list */
+                    niobj->link.prev = (LINK_ELEMENT *)iobj->link.prev;
+                    niobj->link.next = li;
+                    if (li) {
+                        li->prev = (LINK_ELEMENT *)niobj;
+                    }
+
+                    list->prev->next = (LINK_ELEMENT *)niobj;
+                    list = (LINK_ELEMENT *)niobj;
+                    break;
+                  miss:;
+                }
+            }
+        }
+        list = list->next;
     }
 #endif
     return COMPILE_OK;
@@ -3738,28 +3985,28 @@ insn_set_sc_state(rb_iseq_t *iseq, const LINK_ELEMENT *anchor, INSN *iobj, int s
     nstate = SC_NEXT(iobj->insn_id);
 
     if (insn_id == BIN(jump) ||
-	insn_id == BIN(branchif) || insn_id == BIN(branchunless)) {
-	LABEL *lobj = (LABEL *)OPERAND_AT(iobj, 0);
-
-	if (lobj->sc_state != 0) {
-	    if (lobj->sc_state != nstate) {
-		BADINSN_DUMP(anchor, iobj, lobj);
-		COMPILE_ERROR(iseq, iobj->insn_info.line_no,
-			      "insn_set_sc_state error: %d at "LABEL_FORMAT
-			      ", %d expected\n",
-			      lobj->sc_state, lobj->label_no, nstate);
-		return COMPILE_NG;
-	    }
-	}
-	else {
-	    lobj->sc_state = nstate;
-	}
-	if (insn_id == BIN(jump)) {
-	    nstate = SCS_XX;
-	}
+        insn_id == BIN(branchif) || insn_id == BIN(branchunless)) {
+        LABEL *lobj = (LABEL *)OPERAND_AT(iobj, 0);
+
+        if (lobj->sc_state != 0) {
+            if (lobj->sc_state != nstate) {
+                BADINSN_DUMP(anchor, iobj, lobj);
+                COMPILE_ERROR(iseq, iobj->insn_info.line_no,
+                              "insn_set_sc_state error: %d at "LABEL_FORMAT
+                              ", %d expected\n",
+                              lobj->sc_state, lobj->label_no, nstate);
+                return COMPILE_NG;
+            }
+        }
+        else {
+            lobj->sc_state = nstate;
+        }
+        if (insn_id == BIN(jump)) {
+            nstate = SCS_XX;
+        }
     }
     else if (insn_id == BIN(leave)) {
-	nstate = SCS_XX;
+        nstate = SCS_XX;
     }
 
     return nstate;
@@ -3769,12 +4016,12 @@ static int
 label_set_sc_state(LABEL *lobj, int state)
 {
     if (lobj->sc_state != 0) {
-	if (lobj->sc_state != state) {
-	    state = lobj->sc_state;
-	}
+        if (lobj->sc_state != state) {
+            state = lobj->sc_state;
+        }
     }
     else {
-	lobj->sc_state = state;
+        lobj->sc_state = state;
     }
 
     return state;
@@ -3798,84 +4045,84 @@ iseq_set_sequence_stackcaching(rb_iseq_t *iseq, LINK_ANCHOR *const anchor)
     /* for each list element */
     while (list) {
       redo_point:
-	switch (list->type) {
-	  case ISEQ_ELEMENT_INSN:
-	    {
-		INSN *iobj = (INSN *)list;
-		insn_id = iobj->insn_id;
-
-		/* dump_disasm_list(list); */
-
-		switch (insn_id) {
-		  case BIN(nop):
-		    {
-			/* exception merge point */
-			if (state != SCS_AX) {
+        switch (list->type) {
+          case ISEQ_ELEMENT_INSN:
+            {
+                INSN *iobj = (INSN *)list;
+                insn_id = iobj->insn_id;
+
+                /* dump_disasm_list(list); */
+
+                switch (insn_id) {
+                  case BIN(nop):
+                    {
+                        /* exception merge point */
+                        if (state != SCS_AX) {
                             NODE dummy_line_node = generate_dummy_line_node(0, -1);
-			    INSN *rpobj =
-				new_insn_body(iseq, &dummy_line_node, BIN(reput), 0);
-
-			    /* replace this insn */
-			    ELEM_REPLACE(list, (LINK_ELEMENT *)rpobj);
-			    list = (LINK_ELEMENT *)rpobj;
-			    goto redo_point;
-			}
-			break;
-		    }
-		  case BIN(swap):
-		    {
-			if (state == SCS_AB || state == SCS_BA) {
-			    state = (state == SCS_AB ? SCS_BA : SCS_AB);
-
-			    ELEM_REMOVE(list);
-			    list = list->next;
-			    goto redo_point;
-			}
-			break;
-		    }
-		  case BIN(pop):
-		    {
-			switch (state) {
-			  case SCS_AX:
-			  case SCS_BX:
-			    state = SCS_XX;
-			    break;
-			  case SCS_AB:
-			    state = SCS_AX;
-			    break;
-			  case SCS_BA:
-			    state = SCS_BX;
-			    break;
-			  case SCS_XX:
-			    goto normal_insn;
-			  default:
-			    COMPILE_ERROR(iseq, iobj->insn_info.line_no,
-					  "unreachable");
-			    return COMPILE_NG;
-			}
-			/* remove useless pop */
-			ELEM_REMOVE(list);
-			list = list->next;
-			goto redo_point;
-		    }
-		  default:;
-		    /* none */
-		}		/* end of switch */
-	      normal_insn:
-		state = insn_set_sc_state(iseq, anchor, iobj, state);
-		break;
-	    }
-	  case ISEQ_ELEMENT_LABEL:
-	    {
-		LABEL *lobj;
-		lobj = (LABEL *)list;
-
-		state = label_set_sc_state(lobj, state);
-	    }
-	  default:
-	    break;
-	}
-	list = list->next;
+                            INSN *rpobj =
+                                new_insn_body(iseq, &dummy_line_node, BIN(reput), 0);
+
+                            /* replace this insn */
+                            ELEM_REPLACE(list, (LINK_ELEMENT *)rpobj);
+                            list = (LINK_ELEMENT *)rpobj;
+                            goto redo_point;
+                        }
+                        break;
+                    }
+                  case BIN(swap):
+                    {
+                        if (state == SCS_AB || state == SCS_BA) {
+                            state = (state == SCS_AB ? SCS_BA : SCS_AB);
+
+                            ELEM_REMOVE(list);
+                            list = list->next;
+                            goto redo_point;
+                        }
+                        break;
+                    }
+                  case BIN(pop):
+                    {
+                        switch (state) {
+                          case SCS_AX:
+                          case SCS_BX:
+                            state = SCS_XX;
+                            break;
+                          case SCS_AB:
+                            state = SCS_AX;
+                            break;
+                          case SCS_BA:
+                            state = SCS_BX;
+                            break;
+                          case SCS_XX:
+                            goto normal_insn;
+                          default:
+                            COMPILE_ERROR(iseq, iobj->insn_info.line_no,
+                                          "unreachable");
+                            return COMPILE_NG;
+                        }
+                        /* remove useless pop */
+                        ELEM_REMOVE(list);
+                        list = list->next;
+                        goto redo_point;
+                    }
+                  default:;
+                    /* none */
+                }		/* end of switch */
+              normal_insn:
+                state = insn_set_sc_state(iseq, anchor, iobj, state);
+                break;
+            }
+          case ISEQ_ELEMENT_LABEL:
+            {
+                LABEL *lobj;
+                lobj = (LABEL *)list;
+
+                state = label_set_sc_state(lobj, state);
+            }
+          default:
+            break;
+        }
+        list = list->next;
     }
 #endif
     return COMPILE_OK;
@@ -3887,20 +4134,20 @@ all_string_result_p(const NODE *node)
     if (!node) return FALSE;
     switch (nd_type(node)) {
       case NODE_STR: case NODE_DSTR:
-	return TRUE;
+        return TRUE;
       case NODE_IF: case NODE_UNLESS:
-	if (!node->nd_body || !node->nd_else) return FALSE;
-	if (all_string_result_p(node->nd_body))
-	    return all_string_result_p(node->nd_else);
-	return FALSE;
+        if (!node->nd_body || !node->nd_else) return FALSE;
+        if (all_string_result_p(node->nd_body))
+            return all_string_result_p(node->nd_else);
+        return FALSE;
       case NODE_AND: case NODE_OR:
-	if (!node->nd_2nd)
-	    return all_string_result_p(node->nd_1st);
-	if (!all_string_result_p(node->nd_1st))
-	    return FALSE;
-	return all_string_result_p(node->nd_2nd);
+        if (!node->nd_2nd)
+            return all_string_result_p(node->nd_1st);
+        if (!all_string_result_p(node->nd_1st))
+            return FALSE;
+        return all_string_result_p(node->nd_2nd);
       default:
-	return FALSE;
+        return FALSE;
     }
 }
 
@@ -3914,35 +4161,35 @@ compile_dstr_fragments(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *cons
 
     debugp_param("nd_lit", lit);
     if (!NIL_P(lit)) {
-	cnt++;
-	if (!RB_TYPE_P(lit, T_STRING)) {
-	    COMPILE_ERROR(ERROR_ARGS "dstr: must be string: %s",
-			  rb_builtin_type_name(TYPE(lit)));
-	    return COMPILE_NG;
-	}
-	lit = rb_fstring(lit);
-	ADD_INSN1(ret, node, putobject, lit);
+        cnt++;
+        if (!RB_TYPE_P(lit, T_STRING)) {
+            COMPILE_ERROR(ERROR_ARGS "dstr: must be string: %s",
+                          rb_builtin_type_name(TYPE(lit)));
+            return COMPILE_NG;
+        }
+        lit = rb_fstring(lit);
+        ADD_INSN1(ret, node, putobject, lit);
         RB_OBJ_WRITTEN(iseq, Qundef, lit);
-	if (RSTRING_LEN(lit) == 0) first_lit = LAST_ELEMENT(ret);
+        if (RSTRING_LEN(lit) == 0) first_lit = LAST_ELEMENT(ret);
     }
 
     while (list) {
-	const NODE *const head = list->nd_head;
-	if (nd_type_p(head, NODE_STR)) {
-	    lit = rb_fstring(head->nd_lit);
-	    ADD_INSN1(ret, head, putobject, lit);
+        const NODE *const head = list->nd_head;
+        if (nd_type_p(head, NODE_STR)) {
+            lit = rb_fstring(head->nd_lit);
+            ADD_INSN1(ret, head, putobject, lit);
             RB_OBJ_WRITTEN(iseq, Qundef, lit);
-	    lit = Qnil;
-	}
-	else {
-	    CHECK(COMPILE(ret, "each string", head));
-	}
-	cnt++;
-	list = list->nd_next;
+            lit = Qnil;
+        }
+        else {
+            CHECK(COMPILE(ret, "each string", head));
+        }
+        cnt++;
+        list = list->nd_next;
     }
     if (NIL_P(lit) && first_lit) {
-	ELEM_REMOVE(first_lit);
-	--cnt;
+        ELEM_REMOVE(first_lit);
+        --cnt;
     }
     *cntp = cnt;
 
@@ -3990,12 +4237,12 @@ compile_dregx(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node)
 
 static int
 compile_flip_flop(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, int again,
-		  LABEL *then_label, LABEL *else_label)
+                  LABEL *then_label, LABEL *else_label)
 {
     const int line = nd_line(node);
     LABEL *lend = NEW_LABEL(line);
     rb_num_t cnt = ISEQ_FLIP_CNT_INCREMENT(ISEQ_BODY(iseq)->local_iseq)
-	+ VM_SVAR_FLIPFLOP_START;
+        + VM_SVAR_FLIPFLOP_START;
     VALUE key = INT2FIX(cnt);
 
     ADD_INSN2(ret, node, getspecial, key, INT2FIX(0));
@@ -4007,7 +4254,7 @@ compile_flip_flop(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const nod
     ADD_INSN1(ret, node, putobject, Qtrue);
     ADD_INSN1(ret, node, setspecial, key);
     if (!again) {
-	ADD_INSNL(ret, node, jump, then_label);
+        ADD_INSNL(ret, node, jump, then_label);
     }
 
     /* *flip == 1 */
@@ -4023,67 +4270,67 @@ compile_flip_flop(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const nod
 
 static int
 compile_branch_condition(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *cond,
-			 LABEL *then_label, LABEL *else_label)
+                         LABEL *then_label, LABEL *else_label)
 {
   again:
     switch (nd_type(cond)) {
       case NODE_AND:
-	{
-	    LABEL *label = NEW_LABEL(nd_line(cond));
-	    CHECK(compile_branch_condition(iseq, ret, cond->nd_1st, label,
-					   else_label));
+        {
+            LABEL *label = NEW_LABEL(nd_line(cond));
+            CHECK(compile_branch_condition(iseq, ret, cond->nd_1st, label,
+                                           else_label));
             if (!label->refcnt) {
                 ADD_INSN(ret, cond, putnil);
                 break;
             }
-	    ADD_LABEL(ret, label);
-	    cond = cond->nd_2nd;
-	    goto again;
-	}
+            ADD_LABEL(ret, label);
+            cond = cond->nd_2nd;
+            goto again;
+        }
       case NODE_OR:
-	{
-	    LABEL *label = NEW_LABEL(nd_line(cond));
-	    CHECK(compile_branch_condition(iseq, ret, cond->nd_1st, then_label,
-					   label));
+        {
+            LABEL *label = NEW_LABEL(nd_line(cond));
+            CHECK(compile_branch_condition(iseq, ret, cond->nd_1st, then_label,
+                                           label));
             if (!label->refcnt) {
                 ADD_INSN(ret, cond, putnil);
                 break;
             }
-	    ADD_LABEL(ret, label);
-	    cond = cond->nd_2nd;
-	    goto again;
-	}
+            ADD_LABEL(ret, label);
+            cond = cond->nd_2nd;
+            goto again;
+        }
       case NODE_LIT:		/* NODE_LIT is always true */
       case NODE_TRUE:
       case NODE_STR:
       case NODE_ZLIST:
       case NODE_LAMBDA:
-	/* printf("useless condition eliminate (%s)\n",  ruby_node_name(nd_type(cond))); */
-	ADD_INSNL(ret, cond, jump, then_label);
+        /* printf("useless condition eliminate (%s)\n",  ruby_node_name(nd_type(cond))); */
+        ADD_INSNL(ret, cond, jump, then_label);
         return COMPILE_OK;
       case NODE_FALSE:
       case NODE_NIL:
-	/* printf("useless condition eliminate (%s)\n", ruby_node_name(nd_type(cond))); */
-	ADD_INSNL(ret, cond, jump, else_label);
+        /* printf("useless condition eliminate (%s)\n", ruby_node_name(nd_type(cond))); */
+        ADD_INSNL(ret, cond, jump, else_label);
         return COMPILE_OK;
       case NODE_LIST:
       case NODE_ARGSCAT:
       case NODE_DREGX:
       case NODE_DSTR:
-	CHECK(COMPILE_POPPED(ret, "branch condition", cond));
-	ADD_INSNL(ret, cond, jump, then_label);
+        CHECK(COMPILE_POPPED(ret, "branch condition", cond));
+        ADD_INSNL(ret, cond, jump, then_label);
         return COMPILE_OK;
       case NODE_FLIP2:
-	CHECK(compile_flip_flop(iseq, ret, cond, TRUE, then_label, else_label));
+        CHECK(compile_flip_flop(iseq, ret, cond, TRUE, then_label, else_label));
         return COMPILE_OK;
       case NODE_FLIP3:
-	CHECK(compile_flip_flop(iseq, ret, cond, FALSE, then_label, else_label));
+        CHECK(compile_flip_flop(iseq, ret, cond, FALSE, then_label, else_label));
         return COMPILE_OK;
       case NODE_DEFINED:
-	CHECK(compile_defined_expr(iseq, ret, cond, Qfalse));
+        CHECK(compile_defined_expr(iseq, ret, cond, Qfalse));
         break;
       default:
-	CHECK(COMPILE(ret, "branch condition", cond));
+        CHECK(COMPILE(ret, "branch condition", cond));
         break;
     }
 
@@ -4102,25 +4349,25 @@ keyword_node_p(const NODE *const node)
 
 static int
 compile_keyword_arg(rb_iseq_t *iseq, LINK_ANCHOR *const ret,
-			  const NODE *const root_node,
-			  struct rb_callinfo_kwarg **const kw_arg_ptr,
-			  unsigned int *flag)
+                          const NODE *const root_node,
+                          struct rb_callinfo_kwarg **const kw_arg_ptr,
+                          unsigned int *flag)
 {
     if (kw_arg_ptr == NULL) return FALSE;
 
     if (root_node->nd_head && nd_type_p(root_node->nd_head, NODE_LIST)) {
-	const NODE *node = root_node->nd_head;
+        const NODE *node = root_node->nd_head;
         int seen_nodes = 0;
 
-	while (node) {
-	    const NODE *key_node = node->nd_head;
+        while (node) {
+            const NODE *key_node = node->nd_head;
             seen_nodes++;
 
-	    assert(nd_type_p(node, NODE_LIST));
+            assert(nd_type_p(node, NODE_LIST));
             if (key_node && nd_type_p(key_node, NODE_LIT) && SYMBOL_P(key_node->nd_lit)) {
-		/* can be keywords */
-	    }
-	    else {
+                /* can be keywords */
+            }
+            else {
                 if (flag) {
                     *flag |= VM_CALL_KW_SPLAT;
                     if (seen_nodes > 1 || node->nd_next->nd_next) {
@@ -4131,33 +4378,33 @@ compile_keyword_arg(rb_iseq_t *iseq, LINK_ANCHOR *const ret,
                         *flag |= VM_CALL_KW_SPLAT_MUT;
                     }
                 }
-		return FALSE;
-	    }
-	    node = node->nd_next; /* skip value node */
-	    node = node->nd_next;
-	}
-
-	/* may be keywords */
-	node = root_node->nd_head;
-	{
-	    int len = (int)node->nd_alen / 2;
+                return FALSE;
+            }
+            node = node->nd_next; /* skip value node */
+            node = node->nd_next;
+        }
+
+        /* may be keywords */
+        node = root_node->nd_head;
+        {
+            int len = (int)node->nd_alen / 2;
             struct rb_callinfo_kwarg *kw_arg =
                 rb_xmalloc_mul_add(len, sizeof(VALUE), sizeof(struct rb_callinfo_kwarg));
-	    VALUE *keywords = kw_arg->keywords;
-	    int i = 0;
-	    kw_arg->keyword_len = len;
+            VALUE *keywords = kw_arg->keywords;
+            int i = 0;
+            kw_arg->keyword_len = len;
 
-	    *kw_arg_ptr = kw_arg;
+            *kw_arg_ptr = kw_arg;
 
-	    for (i=0; node != NULL; i++, node = node->nd_next->nd_next) {
-		const NODE *key_node = node->nd_head;
-		const NODE *val_node = node->nd_next->nd_head;
-		keywords[i] = key_node->nd_lit;
+            for (i=0; node != NULL; i++, node = node->nd_next->nd_next) {
+                const NODE *key_node = node->nd_head;
+                const NODE *val_node = node->nd_next->nd_head;
+                keywords[i] = key_node->nd_lit;
                 NO_CHECK(COMPILE(ret, "keyword values", val_node));
-	    }
-	    assert(i == len);
-	    return TRUE;
-	}
+            }
+            assert(i == len);
+            return TRUE;
+        }
     }
     return FALSE;
 }
@@ -4197,11 +4444,11 @@ static_literal_node_p(const NODE *node, const rb_iseq_t *iseq)
       case NODE_NIL:
       case NODE_TRUE:
       case NODE_FALSE:
-	return TRUE;
+        return TRUE;
       case NODE_STR:
         return ISEQ_COMPILE_DATA(iseq)->option->frozen_string_literal;
       default:
-	return FALSE;
+        return FALSE;
     }
 }
 
@@ -4210,11 +4457,11 @@ static_literal_value(const NODE *node, rb_iseq_t *iseq)
 {
     switch (nd_type(node)) {
       case NODE_NIL:
-	return Qnil;
+        return Qnil;
       case NODE_TRUE:
-	return Qtrue;
+        return Qtrue;
       case NODE_FALSE:
-	return Qfalse;
+        return Qfalse;
       case NODE_STR:
         if (ISEQ_COMPILE_DATA(iseq)->option->debug_frozen_string_literal || RTEST(ruby_debug)) {
             VALUE lit;
@@ -4227,7 +4474,7 @@ static_literal_value(const NODE *node, rb_iseq_t *iseq)
             return rb_fstring(node->nd_lit);
         }
       default:
-	return node->nd_lit;
+        return node->nd_lit;
     }
 }
 
@@ -4237,9 +4484,9 @@ compile_array(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *node, int pop
     const NODE *line_node = node;
 
     if (nd_type_p(node, NODE_ZLIST)) {
-	if (!popped) {
-	    ADD_INSN1(ret, line_node, newarray, INT2FIX(0));
-	}
+        if (!popped) {
+            ADD_INSN1(ret, line_node, newarray, INT2FIX(0));
+        }
         return 0;
     }
 
@@ -4314,7 +4561,7 @@ compile_array(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *node, int pop
 
             if ((first_chunk && stack_len == 0 && !node_tmp) || count >= min_tmp_ary_len) {
                 /* The literal contains only optimizable elements, or the subarray is long enough */
-                VALUE ary = rb_ary_tmp_new(count);
+                VALUE ary = rb_ary_hidden_new(count);
 
                 /* Create a hidden array */
                 for (; count; count--, node = node->nd_next)
@@ -4365,7 +4612,7 @@ static int
 compile_array_1(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *node)
 {
     if (static_literal_node_p(node, iseq)) {
-        VALUE ary = rb_ary_tmp_new(1);
+        VALUE ary = rb_ary_hidden_new(1);
         rb_ary_push(ary, static_literal_value(node, iseq));
         OBJ_FREEZE(ary);
 
@@ -4373,7 +4620,12 @@ compile_array_1(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *node)
     }
     else {
         CHECK(COMPILE_(ret, "array element", node, FALSE));
-        ADD_INSN1(ret, node, newarray, INT2FIX(1));
+        if (keyword_node_p(node)) {
+            ADD_INSN1(ret, node, newarraykwsplat, INT2FIX(1));
+        }
+        else {
+            ADD_INSN1(ret, node, newarray, INT2FIX(1));
+        }
     }
 
     return 1;
@@ -4393,9 +4645,9 @@ compile_hash(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *node, int meth
     node = node->nd_head;
 
     if (!node || nd_type_p(node, NODE_ZLIST)) {
-	if (!popped) {
-	    ADD_INSN1(ret, line_node, newhash, INT2FIX(0));
-	}
+        if (!popped) {
+            ADD_INSN1(ret, line_node, newhash, INT2FIX(0));
+        }
         return 0;
     }
 
@@ -4462,7 +4714,7 @@ compile_hash(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *node, int meth
 
             if ((first_chunk && stack_len == 0 && !node_tmp) || count >= min_tmp_hash_len) {
                 /* The literal contains only optimizable elements, or the subsequence is long enough */
-                VALUE ary = rb_ary_tmp_new(count);
+                VALUE ary = rb_ary_hidden_new(count);
 
                 /* Create a hidden hash */
                 for (; count; count--, node = node->nd_next->nd_next) {
@@ -4580,62 +4832,62 @@ rb_node_case_when_optimizable_literal(const NODE *const node)
 {
     switch (nd_type(node)) {
       case NODE_LIT: {
-	VALUE v = node->nd_lit;
-	double ival;
-	if (RB_FLOAT_TYPE_P(v) &&
-	    modf(RFLOAT_VALUE(v), &ival) == 0.0) {
-	    return FIXABLE(ival) ? LONG2FIX((long)ival) : rb_dbl2big(ival);
-	}
+        VALUE v = node->nd_lit;
+        double ival;
+        if (RB_FLOAT_TYPE_P(v) &&
+            modf(RFLOAT_VALUE(v), &ival) == 0.0) {
+            return FIXABLE(ival) ? LONG2FIX((long)ival) : rb_dbl2big(ival);
+        }
         if (RB_TYPE_P(v, T_RATIONAL) || RB_TYPE_P(v, T_COMPLEX)) {
             return Qundef;
         }
-	if (SYMBOL_P(v) || rb_obj_is_kind_of(v, rb_cNumeric)) {
-	    return v;
-	}
-	break;
+        if (SYMBOL_P(v) || rb_obj_is_kind_of(v, rb_cNumeric)) {
+            return v;
+        }
+        break;
       }
       case NODE_NIL:
-	return Qnil;
+        return Qnil;
       case NODE_TRUE:
-	return Qtrue;
+        return Qtrue;
       case NODE_FALSE:
-	return Qfalse;
+        return Qfalse;
       case NODE_STR:
-	return rb_fstring(node->nd_lit);
+        return rb_fstring(node->nd_lit);
     }
     return Qundef;
 }
 
 static int
 when_vals(rb_iseq_t *iseq, LINK_ANCHOR *const cond_seq, const NODE *vals,
-	  LABEL *l1, int only_special_literals, VALUE literals)
+          LABEL *l1, int only_special_literals, VALUE literals)
 {
     while (vals) {
-	const NODE *val = vals->nd_head;
+        const NODE *val = vals->nd_head;
         VALUE lit = rb_node_case_when_optimizable_literal(val);
 
-	if (lit == Qundef) {
-	    only_special_literals = 0;
-	}
+        if (UNDEF_P(lit)) {
+            only_special_literals = 0;
+        }
         else if (NIL_P(rb_hash_lookup(literals, lit))) {
             rb_hash_aset(literals, lit, (VALUE)(l1) | 1);
-	}
+        }
 
-	if (nd_type_p(val, NODE_STR)) {
-	    debugp_param("nd_lit", val->nd_lit);
-	    lit = rb_fstring(val->nd_lit);
-	    ADD_INSN1(cond_seq, val, putobject, lit);
+        if (nd_type_p(val, NODE_STR)) {
+            debugp_param("nd_lit", val->nd_lit);
+            lit = rb_fstring(val->nd_lit);
+            ADD_INSN1(cond_seq, val, putobject, lit);
             RB_OBJ_WRITTEN(iseq, Qundef, lit);
-	}
-	else {
-	    if (!COMPILE(cond_seq, "when cond", val)) return -1;
-	}
+        }
+        else {
+            if (!COMPILE(cond_seq, "when cond", val)) return -1;
+        }
 
         // Emit patern === target
         ADD_INSN1(cond_seq, vals, topn, INT2FIX(1));
         ADD_CALL(cond_seq, vals, idEqq, INT2FIX(1));
-	ADD_INSNL(cond_seq, val, branchif, l1);
-	vals = vals->nd_next;
+        ADD_INSNL(cond_seq, val, branchif, l1);
+        vals = vals->nd_next;
     }
     return only_special_literals;
 }
@@ -4782,7 +5034,8 @@ struct masgn_state {
 };
 
 static int
-add_masgn_lhs_node(struct masgn_state *state, int lhs_pos, const NODE *line_node, int argc, INSN *before_insn) {
+add_masgn_lhs_node(struct masgn_state *state, int lhs_pos, const NODE *line_node, int argc, INSN *before_insn)
+{
     if (!state) {
         rb_bug("no masgn_state");
     }
@@ -4818,17 +5071,22 @@ compile_massign_lhs(rb_iseq_t *iseq, LINK_ANCHOR *const pre, LINK_ANCHOR *const
 {
     switch (nd_type(node)) {
       case NODE_ATTRASGN: {
-	INSN *iobj;
+        INSN *iobj;
         const NODE *line_node = node;
 
         CHECK(COMPILE_POPPED(pre, "masgn lhs (NODE_ATTRASGN)", node));
 
+        bool safenav_call = false;
         LINK_ELEMENT *insn_element = LAST_ELEMENT(pre);
         iobj = (INSN *)get_prev_insn((INSN *)insn_element); /* send insn */
-	ASSUME(iobj);
-        ELEM_REMOVE(LAST_ELEMENT(pre));
-        ELEM_REMOVE((LINK_ELEMENT *)iobj);
-        pre->last = iobj->link.prev;
+        ASSUME(iobj);
+        ELEM_REMOVE(insn_element);
+        if (!IS_INSN_ID(iobj, send)) {
+            safenav_call = true;
+            iobj = (INSN *)get_prev_insn(iobj);
+            ELEM_INSERT_NEXT(&iobj->link, insn_element);
+        }
+        (pre->last = iobj->link.prev)->next = 0;
 
         const struct rb_callinfo *ci = (struct rb_callinfo *)OPERAND_AT(iobj, 0);
         int argc = vm_ci_argc(ci) + 1;
@@ -4847,23 +5105,27 @@ compile_massign_lhs(rb_iseq_t *iseq, LINK_ANCHOR *const pre, LINK_ANCHOR *const
             return COMPILE_NG;
         }
 
-        ADD_ELEM(lhs, (LINK_ELEMENT *)iobj);
-	if (vm_ci_flag(ci) & VM_CALL_ARGS_SPLAT) {
+        iobj->link.prev = lhs->last;
+        lhs->last->next = &iobj->link;
+        for (lhs->last = &iobj->link; lhs->last->next; lhs->last = lhs->last->next);
+        if (vm_ci_flag(ci) & VM_CALL_ARGS_SPLAT) {
             int argc = vm_ci_argc(ci);
             ci = ci_argc_set(iseq, ci, argc - 1);
             OPERAND_AT(iobj, 0) = (VALUE)ci;
             RB_OBJ_WRITTEN(iseq, Qundef, iobj);
             INSERT_BEFORE_INSN1(iobj, line_node, newarray, INT2FIX(1));
-	    INSERT_BEFORE_INSN(iobj, line_node, concatarray);
-	}
-        ADD_INSN(lhs, line_node, pop);
-        if (argc != 1) {
+            INSERT_BEFORE_INSN(iobj, line_node, concatarray);
+        }
+        if (!safenav_call) {
             ADD_INSN(lhs, line_node, pop);
+            if (argc != 1) {
+                ADD_INSN(lhs, line_node, pop);
+            }
         }
         for (int i=0; i < argc; i++) {
             ADD_INSN(post, line_node, pop);
         }
-	break;
+        break;
       }
       case NODE_MASGN: {
         DECL_ANCHOR(nest_rhs);
@@ -4881,7 +5143,7 @@ compile_massign_lhs(rb_iseq_t *iseq, LINK_ANCHOR *const pre, LINK_ANCHOR *const
 
         ADD_SEQ(lhs, nest_rhs);
         ADD_SEQ(lhs, nest_lhs);
-	break;
+        break;
       }
       case NODE_CDECL:
         if (!node->nd_vid) {
@@ -4907,10 +5169,10 @@ compile_massign_lhs(rb_iseq_t *iseq, LINK_ANCHOR *const pre, LINK_ANCHOR *const
         }
         /* Fallthrough */
       default: {
-	DECL_ANCHOR(anchor);
-	INIT_ANCHOR(anchor);
-	CHECK(COMPILE_POPPED(anchor, "masgn lhs", node));
-	ELEM_REMOVE(FIRST_ELEMENT(anchor));
+        DECL_ANCHOR(anchor);
+        INIT_ANCHOR(anchor);
+        CHECK(COMPILE_POPPED(anchor, "masgn lhs", node));
+        ELEM_REMOVE(FIRST_ELEMENT(anchor));
         ADD_SEQ(lhs, anchor);
       }
     }
@@ -4922,7 +5184,7 @@ static int
 compile_massign_opt_lhs(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *lhsn)
 {
     if (lhsn) {
-	CHECK(compile_massign_opt_lhs(iseq, ret, lhsn->nd_next));
+        CHECK(compile_massign_opt_lhs(iseq, ret, lhsn->nd_next));
         CHECK(compile_massign_lhs(iseq, ret, ret, ret, ret, lhsn->nd_head, NULL, 0));
     }
     return COMPILE_OK;
@@ -4930,7 +5192,7 @@ compile_massign_opt_lhs(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *lhs
 
 static int
 compile_massign_opt(rb_iseq_t *iseq, LINK_ANCHOR *const ret,
-		    const NODE *rhsn, const NODE *orig_lhsn)
+                    const NODE *rhsn, const NODE *orig_lhsn)
 {
     VALUE mem[64];
     const int memsize = numberof(mem);
@@ -4943,48 +5205,48 @@ compile_massign_opt(rb_iseq_t *iseq, LINK_ANCHOR *const ret,
     int i; \
     if (memindex == memsize) return 0; \
     for (i=0; i<memindex; i++) { \
-	if (mem[i] == (v)) return 0; \
+        if (mem[i] == (v)) return 0; \
     } \
     mem[memindex++] = (v); \
 }
 
     if (rhsn == 0 || !nd_type_p(rhsn, NODE_LIST)) {
-	return 0;
+        return 0;
     }
 
     while (lhsn) {
-	const NODE *ln = lhsn->nd_head;
-	switch (nd_type(ln)) {
-	  case NODE_LASGN:
-	    MEMORY(ln->nd_vid);
-	    break;
-	  case NODE_DASGN:
-	  case NODE_IASGN:
-	  case NODE_CVASGN:
-	    MEMORY(ln->nd_vid);
-	    break;
-	  default:
-	    return 0;
-	}
-	lhsn = lhsn->nd_next;
-	llen++;
+        const NODE *ln = lhsn->nd_head;
+        switch (nd_type(ln)) {
+          case NODE_LASGN:
+            MEMORY(ln->nd_vid);
+            break;
+          case NODE_DASGN:
+          case NODE_IASGN:
+          case NODE_CVASGN:
+            MEMORY(ln->nd_vid);
+            break;
+          default:
+            return 0;
+        }
+        lhsn = lhsn->nd_next;
+        llen++;
     }
 
     while (rhsn) {
-	if (llen <= rlen) {
+        if (llen <= rlen) {
             NO_CHECK(COMPILE_POPPED(ret, "masgn val (popped)", rhsn->nd_head));
-	}
-	else {
+        }
+        else {
             NO_CHECK(COMPILE(ret, "masgn val", rhsn->nd_head));
-	}
-	rhsn = rhsn->nd_next;
-	rlen++;
+        }
+        rhsn = rhsn->nd_next;
+        rlen++;
     }
 
     if (llen > rlen) {
-	for (i=0; i<llen-rlen; i++) {
-	    ADD_INSN(ret, orig_lhsn, putnil);
-	}
+        for (i=0; i<llen-rlen; i++) {
+            ADD_INSN(ret, orig_lhsn, putnil);
+        }
     }
 
     compile_massign_opt_lhs(iseq, ret, orig_lhsn);
@@ -5099,32 +5361,55 @@ compile_massign(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node,
     return COMPILE_OK;
 }
 
+static VALUE
+collect_const_segments(rb_iseq_t *iseq, const NODE *node)
+{
+    VALUE arr = rb_ary_new();
+    for (;;) {
+        switch (nd_type(node)) {
+          case NODE_CONST:
+            rb_ary_unshift(arr, ID2SYM(node->nd_vid));
+            return arr;
+          case NODE_COLON3:
+            rb_ary_unshift(arr, ID2SYM(node->nd_mid));
+            rb_ary_unshift(arr, ID2SYM(idNULL));
+            return arr;
+          case NODE_COLON2:
+            rb_ary_unshift(arr, ID2SYM(node->nd_mid));
+            node = node->nd_head;
+            break;
+          default:
+            return Qfalse;
+        }
+    }
+}
+
 static int
 compile_const_prefix(rb_iseq_t *iseq, const NODE *const node,
-		     LINK_ANCHOR *const pref, LINK_ANCHOR *const body)
+                     LINK_ANCHOR *const pref, LINK_ANCHOR *const body)
 {
     switch (nd_type(node)) {
       case NODE_CONST:
-	debugi("compile_const_prefix - colon", node->nd_vid);
+        debugi("compile_const_prefix - colon", node->nd_vid);
         ADD_INSN1(body, node, putobject, Qtrue);
         ADD_INSN1(body, node, getconstant, ID2SYM(node->nd_vid));
-	break;
+        break;
       case NODE_COLON3:
-	debugi("compile_const_prefix - colon3", node->nd_mid);
-	ADD_INSN(body, node, pop);
-	ADD_INSN1(body, node, putobject, rb_cObject);
+        debugi("compile_const_prefix - colon3", node->nd_mid);
+        ADD_INSN(body, node, pop);
+        ADD_INSN1(body, node, putobject, rb_cObject);
         ADD_INSN1(body, node, putobject, Qtrue);
         ADD_INSN1(body, node, getconstant, ID2SYM(node->nd_mid));
-	break;
+        break;
       case NODE_COLON2:
-	CHECK(compile_const_prefix(iseq, node->nd_head, pref, body));
-	debugi("compile_const_prefix - colon2", node->nd_mid);
+        CHECK(compile_const_prefix(iseq, node->nd_head, pref, body));
+        debugi("compile_const_prefix - colon2", node->nd_mid);
         ADD_INSN1(body, node, putobject, Qfalse);
         ADD_INSN1(body, node, getconstant, ID2SYM(node->nd_mid));
-	break;
+        break;
       default:
-	CHECK(COMPILE(pref, "const colon2 prefix", node));
-	break;
+        CHECK(COMPILE(pref, "const colon2 prefix", node));
+        break;
     }
     return COMPILE_OK;
 }
@@ -5133,20 +5418,20 @@ static int
 compile_cpath(LINK_ANCHOR *const ret, rb_iseq_t *iseq, const NODE *cpath)
 {
     if (nd_type_p(cpath, NODE_COLON3)) {
-	/* toplevel class ::Foo */
-	ADD_INSN1(ret, cpath, putobject, rb_cObject);
-	return VM_DEFINECLASS_FLAG_SCOPED;
+        /* toplevel class ::Foo */
+        ADD_INSN1(ret, cpath, putobject, rb_cObject);
+        return VM_DEFINECLASS_FLAG_SCOPED;
     }
     else if (cpath->nd_head) {
-	/* Bar::Foo */
+        /* Bar::Foo */
         NO_CHECK(COMPILE(ret, "nd_else->nd_head", cpath->nd_head));
-	return VM_DEFINECLASS_FLAG_SCOPED;
+        return VM_DEFINECLASS_FLAG_SCOPED;
     }
     else {
-	/* class at cbase Foo */
-	ADD_INSN1(ret, cpath, putspecialobject,
-		  INT2FIX(VM_SPECIAL_OBJECT_CONST_BASE));
-	return 0;
+        /* class at cbase Foo */
+        ADD_INSN1(ret, cpath, putspecialobject,
+                  INT2FIX(VM_SPECIAL_OBJECT_CONST_BASE));
+        return 0;
     }
 }
 
@@ -5162,7 +5447,7 @@ private_recv_p(const NODE *node)
 
 static void
 defined_expr(rb_iseq_t *iseq, LINK_ANCHOR *const ret,
-	     const NODE *const node, LABEL **lfinish, VALUE needstr);
+             const NODE *const node, LABEL **lfinish, VALUE needstr);
 
 static int
 compile_call(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, const enum node_type type, const NODE *const line_node, int popped, bool assume_receiver);
@@ -5179,31 +5464,31 @@ defined_expr0(rb_iseq_t *iseq, LINK_ANCHOR *const ret,
 
     switch (type = nd_type(node)) {
 
-	/* easy literals */
+        /* easy literals */
       case NODE_NIL:
-	expr_type = DEFINED_NIL;
-	break;
+        expr_type = DEFINED_NIL;
+        break;
       case NODE_SELF:
-	expr_type = DEFINED_SELF;
-	break;
+        expr_type = DEFINED_SELF;
+        break;
       case NODE_TRUE:
-	expr_type = DEFINED_TRUE;
-	break;
+        expr_type = DEFINED_TRUE;
+        break;
       case NODE_FALSE:
-	expr_type = DEFINED_FALSE;
-	break;
+        expr_type = DEFINED_FALSE;
+        break;
 
       case NODE_LIST:{
-	const NODE *vals = node;
+        const NODE *vals = node;
 
-	do {
+        do {
             defined_expr0(iseq, ret, vals->nd_head, lfinish, Qfalse, false);
 
-	    if (!lfinish[1]) {
+            if (!lfinish[1]) {
                 lfinish[1] = NEW_LABEL(line);
-	    }
+            }
             ADD_INSNL(ret, line_node, branchunless, lfinish[1]);
-	} while ((vals = vals->nd_next) != NULL);
+        } while ((vals = vals->nd_next) != NULL);
       }
         /* fall through */
       case NODE_STR:
@@ -5212,43 +5497,43 @@ defined_expr0(rb_iseq_t *iseq, LINK_ANCHOR *const ret,
       case NODE_AND:
       case NODE_OR:
       default:
-	expr_type = DEFINED_EXPR;
-	break;
+        expr_type = DEFINED_EXPR;
+        break;
 
-	/* variables */
+        /* variables */
       case NODE_LVAR:
       case NODE_DVAR:
-	expr_type = DEFINED_LVAR;
-	break;
+        expr_type = DEFINED_LVAR;
+        break;
 
 #define PUSH_VAL(type) (needstr == Qfalse ? Qtrue : rb_iseq_defined_string(type))
       case NODE_IVAR:
         ADD_INSN(ret, line_node, putnil);
         ADD_INSN3(ret, line_node, defined, INT2FIX(DEFINED_IVAR),
-		  ID2SYM(node->nd_vid), PUSH_VAL(DEFINED_IVAR));
+                  ID2SYM(node->nd_vid), PUSH_VAL(DEFINED_IVAR));
         return;
 
       case NODE_GVAR:
         ADD_INSN(ret, line_node, putnil);
         ADD_INSN3(ret, line_node, defined, INT2FIX(DEFINED_GVAR),
-		  ID2SYM(node->nd_entry), PUSH_VAL(DEFINED_GVAR));
+                  ID2SYM(node->nd_entry), PUSH_VAL(DEFINED_GVAR));
         return;
 
       case NODE_CVAR:
         ADD_INSN(ret, line_node, putnil);
         ADD_INSN3(ret, line_node, defined, INT2FIX(DEFINED_CVAR),
-		  ID2SYM(node->nd_vid), PUSH_VAL(DEFINED_CVAR));
+                  ID2SYM(node->nd_vid), PUSH_VAL(DEFINED_CVAR));
         return;
 
       case NODE_CONST:
         ADD_INSN(ret, line_node, putnil);
         ADD_INSN3(ret, line_node, defined, INT2FIX(DEFINED_CONST),
-		  ID2SYM(node->nd_vid), PUSH_VAL(DEFINED_CONST));
+                  ID2SYM(node->nd_vid), PUSH_VAL(DEFINED_CONST));
         return;
       case NODE_COLON2:
-	if (!lfinish[1]) {
+        if (!lfinish[1]) {
             lfinish[1] = NEW_LABEL(line);
-	}
+        }
         defined_expr0(iseq, ret, node->nd_head, lfinish, Qfalse, false);
         ADD_INSNL(ret, line_node, branchunless, lfinish[1]);
         NO_CHECK(COMPILE(ret, "defined/colon2#nd_head", node->nd_head));
@@ -5265,18 +5550,18 @@ defined_expr0(rb_iseq_t *iseq, LINK_ANCHOR *const ret,
       case NODE_COLON3:
         ADD_INSN1(ret, line_node, putobject, rb_cObject);
         ADD_INSN3(ret, line_node, defined,
-		  INT2FIX(DEFINED_CONST_FROM), ID2SYM(node->nd_mid), PUSH_VAL(DEFINED_CONST));
+                  INT2FIX(DEFINED_CONST_FROM), ID2SYM(node->nd_mid), PUSH_VAL(DEFINED_CONST));
         return;
 
-	/* method dispatch */
+        /* method dispatch */
       case NODE_CALL:
       case NODE_OPCALL:
       case NODE_VCALL:
       case NODE_FCALL:
       case NODE_ATTRASGN:{
-	const int explicit_receiver =
-	    (type == NODE_CALL || type == NODE_OPCALL ||
-	     (type == NODE_ATTRASGN && !private_recv_p(node)));
+        const int explicit_receiver =
+            (type == NODE_CALL || type == NODE_OPCALL ||
+             (type == NODE_ATTRASGN && !private_recv_p(node)));
 
         if (node->nd_args || explicit_receiver) {
             if (!lfinish[1]) {
@@ -5286,11 +5571,11 @@ defined_expr0(rb_iseq_t *iseq, LINK_ANCHOR *const ret,
                 lfinish[2] = NEW_LABEL(line);
             }
         }
-	if (node->nd_args) {
+        if (node->nd_args) {
             defined_expr0(iseq, ret, node->nd_args, lfinish, Qfalse, false);
             ADD_INSNL(ret, line_node, branchunless, lfinish[1]);
-	}
-	if (explicit_receiver) {
+        }
+        if (explicit_receiver) {
             defined_expr0(iseq, ret, node->nd_recv, lfinish, Qfalse, true);
             switch (nd_type(node->nd_recv)) {
               case NODE_CALL:
@@ -5310,38 +5595,38 @@ defined_expr0(rb_iseq_t *iseq, LINK_ANCHOR *const ret,
                 ADD_INSN(ret, line_node, dup);
             }
             ADD_INSN3(ret, line_node, defined, INT2FIX(DEFINED_METHOD),
-		      ID2SYM(node->nd_mid), PUSH_VAL(DEFINED_METHOD));
-	}
-	else {
+                      ID2SYM(node->nd_mid), PUSH_VAL(DEFINED_METHOD));
+        }
+        else {
             ADD_INSN(ret, line_node, putself);
             if (keep_result) {
                 ADD_INSN(ret, line_node, dup);
             }
             ADD_INSN3(ret, line_node, defined, INT2FIX(DEFINED_FUNC),
-		      ID2SYM(node->nd_mid), PUSH_VAL(DEFINED_METHOD));
-	}
+                      ID2SYM(node->nd_mid), PUSH_VAL(DEFINED_METHOD));
+        }
         return;
       }
 
       case NODE_YIELD:
         ADD_INSN(ret, line_node, putnil);
         ADD_INSN3(ret, line_node, defined, INT2FIX(DEFINED_YIELD), 0,
-		  PUSH_VAL(DEFINED_YIELD));
+                  PUSH_VAL(DEFINED_YIELD));
         return;
 
       case NODE_BACK_REF:
       case NODE_NTH_REF:
         ADD_INSN(ret, line_node, putnil);
         ADD_INSN3(ret, line_node, defined, INT2FIX(DEFINED_REF),
-		  INT2FIX((node->nd_nth << 1) | (type == NODE_BACK_REF)),
-		  PUSH_VAL(DEFINED_GVAR));
+                  INT2FIX((node->nd_nth << 1) | (type == NODE_BACK_REF)),
+                  PUSH_VAL(DEFINED_GVAR));
         return;
 
       case NODE_SUPER:
       case NODE_ZSUPER:
         ADD_INSN(ret, line_node, putnil);
         ADD_INSN3(ret, line_node, defined, INT2FIX(DEFINED_ZSUPER), 0,
-		  PUSH_VAL(DEFINED_ZSUPER));
+                  PUSH_VAL(DEFINED_ZSUPER));
         return;
 
 #undef PUSH_VAL
@@ -5356,8 +5641,8 @@ defined_expr0(rb_iseq_t *iseq, LINK_ANCHOR *const ret,
       case NODE_IASGN:
       case NODE_CDECL:
       case NODE_CVASGN:
-	expr_type = DEFINED_ASGN;
-	break;
+        expr_type = DEFINED_ASGN;
+        break;
     }
 
     assert(expr_type != DEFINED_NOT_DEFINED);
@@ -5381,26 +5666,26 @@ build_defined_rescue_iseq(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const void *u
 
 static void
 defined_expr(rb_iseq_t *iseq, LINK_ANCHOR *const ret,
-	     const NODE *const node, LABEL **lfinish, VALUE needstr)
+             const NODE *const node, LABEL **lfinish, VALUE needstr)
 {
     LINK_ELEMENT *lcur = ret->last;
     defined_expr0(iseq, ret, node, lfinish, needstr, false);
     if (lfinish[1]) {
-	int line = nd_line(node);
-	LABEL *lstart = NEW_LABEL(line);
-	LABEL *lend = NEW_LABEL(line);
-	const rb_iseq_t *rescue;
+        int line = nd_line(node);
+        LABEL *lstart = NEW_LABEL(line);
+        LABEL *lend = NEW_LABEL(line);
+        const rb_iseq_t *rescue;
         struct rb_iseq_new_with_callback_callback_func *ifunc =
             rb_iseq_new_with_callback_new_callback(build_defined_rescue_iseq, NULL);
         rescue = new_child_iseq_with_callback(iseq, ifunc,
                                               rb_str_concat(rb_str_new2("defined guard in "),
                                                             ISEQ_BODY(iseq)->location.label),
                                               iseq, ISEQ_TYPE_RESCUE, 0);
-	lstart->rescued = LABEL_RESCUE_BEG;
-	lend->rescued = LABEL_RESCUE_END;
-	APPEND_LABEL(ret, lcur, lstart);
-	ADD_LABEL(ret, lend);
-	ADD_CATCH_ENTRY(CATCH_TYPE_RESCUE, lstart, lend, rescue, lfinish[1]);
+        lstart->rescued = LABEL_RESCUE_BEG;
+        lend->rescued = LABEL_RESCUE_END;
+        APPEND_LABEL(ret, lcur, lstart);
+        ADD_LABEL(ret, lend);
+        ADD_CATCH_ENTRY(CATCH_TYPE_RESCUE, lstart, lend, rescue, lfinish[1]);
     }
 }
 
@@ -5410,26 +5695,26 @@ compile_defined_expr(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const
     const int line = nd_line(node);
     const NODE *line_node = node;
     if (!node->nd_head) {
-	VALUE str = rb_iseq_defined_string(DEFINED_NIL);
-	ADD_INSN1(ret, line_node, putobject, str);
+        VALUE str = rb_iseq_defined_string(DEFINED_NIL);
+        ADD_INSN1(ret, line_node, putobject, str);
     }
     else {
         LABEL *lfinish[3];
-	LINK_ELEMENT *last = ret->last;
-	lfinish[0] = NEW_LABEL(line);
-	lfinish[1] = 0;
+        LINK_ELEMENT *last = ret->last;
+        lfinish[0] = NEW_LABEL(line);
+        lfinish[1] = 0;
         lfinish[2] = 0;
-	defined_expr(iseq, ret, node->nd_head, lfinish, needstr);
-	if (lfinish[1]) {
-	    ELEM_INSERT_NEXT(last, &new_insn_body(iseq, line_node, BIN(putnil), 0)->link);
-	    ADD_INSN(ret, line_node, swap);
+        defined_expr(iseq, ret, node->nd_head, lfinish, needstr);
+        if (lfinish[1]) {
+            ELEM_INSERT_NEXT(last, &new_insn_body(iseq, line_node, BIN(putnil), 0)->link);
+            ADD_INSN(ret, line_node, swap);
             if (lfinish[2]) {
                 ADD_LABEL(ret, lfinish[2]);
             }
-	    ADD_INSN(ret, line_node, pop);
-	    ADD_LABEL(ret, lfinish[1]);
-	}
-	ADD_LABEL(ret, lfinish[0]);
+            ADD_INSN(ret, line_node, pop);
+            ADD_LABEL(ret, lfinish[1]);
+        }
+        ADD_LABEL(ret, lfinish[0]);
     }
     return COMPILE_OK;
 }
@@ -5443,10 +5728,10 @@ make_name_for_block(const rb_iseq_t *orig_iseq)
     if (ISEQ_BODY(orig_iseq)->parent_iseq != 0) {
         while (ISEQ_BODY(orig_iseq)->local_iseq != iseq) {
             if (ISEQ_BODY(iseq)->type == ISEQ_TYPE_BLOCK) {
-		level++;
-	    }
+                level++;
+            }
             iseq = ISEQ_BODY(iseq)->parent_iseq;
-	}
+        }
     }
 
     if (level == 1) {
@@ -5459,8 +5744,8 @@ make_name_for_block(const rb_iseq_t *orig_iseq)
 
 static void
 push_ensure_entry(rb_iseq_t *iseq,
-		  struct iseq_compile_data_ensure_node_stack *enl,
-		  struct ensure_range *er, const NODE *const node)
+                  struct iseq_compile_data_ensure_node_stack *enl,
+                  struct ensure_range *er, const NODE *const node)
 {
     enl->ensure_node = node;
     enl->prev = ISEQ_COMPILE_DATA(iseq)->ensure_node_stack;	/* prev */
@@ -5470,13 +5755,13 @@ push_ensure_entry(rb_iseq_t *iseq,
 
 static void
 add_ensure_range(rb_iseq_t *iseq, struct ensure_range *erange,
-		 LABEL *lstart, LABEL *lend)
+                 LABEL *lstart, LABEL *lend)
 {
     struct ensure_range *ne =
-	compile_data_alloc(iseq, sizeof(struct ensure_range));
+        compile_data_alloc(iseq, sizeof(struct ensure_range));
 
     while (erange->next != 0) {
-	erange = erange->next;
+        erange = erange->next;
     }
     ne->next = 0;
     ne->begin = lend;
@@ -5505,32 +5790,32 @@ add_ensure_iseq(LINK_ANCHOR *const ret, rb_iseq_t *iseq, int is_return)
     assert(can_add_ensure_iseq(iseq));
 
     struct iseq_compile_data_ensure_node_stack *enlp =
-	ISEQ_COMPILE_DATA(iseq)->ensure_node_stack;
+        ISEQ_COMPILE_DATA(iseq)->ensure_node_stack;
     struct iseq_compile_data_ensure_node_stack *prev_enlp = enlp;
     DECL_ANCHOR(ensure);
 
     INIT_ANCHOR(ensure);
     while (enlp) {
-	if (enlp->erange != NULL) {
-	    DECL_ANCHOR(ensure_part);
-	    LABEL *lstart = NEW_LABEL(0);
-	    LABEL *lend = NEW_LABEL(0);
-	    INIT_ANCHOR(ensure_part);
+        if (enlp->erange != NULL) {
+            DECL_ANCHOR(ensure_part);
+            LABEL *lstart = NEW_LABEL(0);
+            LABEL *lend = NEW_LABEL(0);
+            INIT_ANCHOR(ensure_part);
 
-	    add_ensure_range(iseq, enlp->erange, lstart, lend);
+            add_ensure_range(iseq, enlp->erange, lstart, lend);
 
-	    ISEQ_COMPILE_DATA(iseq)->ensure_node_stack = enlp->prev;
-	    ADD_LABEL(ensure_part, lstart);
+            ISEQ_COMPILE_DATA(iseq)->ensure_node_stack = enlp->prev;
+            ADD_LABEL(ensure_part, lstart);
             NO_CHECK(COMPILE_POPPED(ensure_part, "ensure part", enlp->ensure_node));
-	    ADD_LABEL(ensure_part, lend);
-	    ADD_SEQ(ensure, ensure_part);
-	}
-	else {
-	    if (!is_return) {
-		break;
-	    }
-	}
-	enlp = enlp->prev;
+            ADD_LABEL(ensure_part, lend);
+            ADD_SEQ(ensure, ensure_part);
+        }
+        else {
+            if (!is_return) {
+                break;
+            }
+        }
+        enlp = enlp->prev;
     }
     ISEQ_COMPILE_DATA(iseq)->ensure_node_stack = prev_enlp;
     ADD_SEQ(ret, ensure);
@@ -5613,7 +5898,7 @@ setup_args_core(rb_iseq_t *iseq, LINK_ANCHOR *const args, const NODE *argn,
 
 static VALUE
 setup_args(rb_iseq_t *iseq, LINK_ANCHOR *const args, const NODE *argn,
-	   unsigned int *flag, struct rb_callinfo_kwarg **keywords)
+           unsigned int *flag, struct rb_callinfo_kwarg **keywords)
 {
     VALUE ret;
     if (argn && nd_type_p(argn, NODE_BLOCK_PASS)) {
@@ -5675,44 +5960,44 @@ compile_named_capture_assign(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE
     ADD_INSNL(ret, line_node, branchunless, fail_label);
 
     for (vars = node; vars; vars = vars->nd_next) {
-	INSN *cap;
-	if (vars->nd_next) {
-	    ADD_INSN(ret, line_node, dup);
-	}
-	last = ret->last;
+        INSN *cap;
+        if (vars->nd_next) {
+            ADD_INSN(ret, line_node, dup);
+        }
+        last = ret->last;
         NO_CHECK(COMPILE_POPPED(ret, "capture", vars->nd_head));
-	last = last->next; /* putobject :var */
-	cap = new_insn_send(iseq, line_node, idAREF, INT2FIX(1),
-			    NULL, INT2FIX(0), NULL);
-	ELEM_INSERT_PREV(last->next, (LINK_ELEMENT *)cap);
+        last = last->next; /* putobject :var */
+        cap = new_insn_send(iseq, line_node, idAREF, INT2FIX(1),
+                            NULL, INT2FIX(0), NULL);
+        ELEM_INSERT_PREV(last->next, (LINK_ELEMENT *)cap);
 #if !defined(NAMED_CAPTURE_SINGLE_OPT) || NAMED_CAPTURE_SINGLE_OPT-0
-	if (!vars->nd_next && vars == node) {
-	    /* only one name */
-	    DECL_ANCHOR(nom);
+        if (!vars->nd_next && vars == node) {
+            /* only one name */
+            DECL_ANCHOR(nom);
 
-	    INIT_ANCHOR(nom);
-	    ADD_INSNL(nom, line_node, jump, end_label);
-	    ADD_LABEL(nom, fail_label);
+            INIT_ANCHOR(nom);
+            ADD_INSNL(nom, line_node, jump, end_label);
+            ADD_LABEL(nom, fail_label);
 # if 0				/* $~ must be MatchData or nil */
-	    ADD_INSN(nom, line_node, pop);
-	    ADD_INSN(nom, line_node, putnil);
+            ADD_INSN(nom, line_node, pop);
+            ADD_INSN(nom, line_node, putnil);
 # endif
-	    ADD_LABEL(nom, end_label);
-	    (nom->last->next = cap->link.next)->prev = nom->last;
-	    (cap->link.next = nom->anchor.next)->prev = &cap->link;
-	    return;
-	}
+            ADD_LABEL(nom, end_label);
+            (nom->last->next = cap->link.next)->prev = nom->last;
+            (cap->link.next = nom->anchor.next)->prev = &cap->link;
+            return;
+        }
 #endif
     }
     ADD_INSNL(ret, line_node, jump, end_label);
     ADD_LABEL(ret, fail_label);
     ADD_INSN(ret, line_node, pop);
     for (vars = node; vars; vars = vars->nd_next) {
-	last = ret->last;
+        last = ret->last;
         NO_CHECK(COMPILE_POPPED(ret, "capture", vars->nd_head));
-	last = last->next; /* putobject :var */
-	((INSN*)last)->insn_id = BIN(putnil);
-	((INSN*)last)->operand_size = 0;
+        last = last->next; /* putobject :var */
+        ((INSN*)last)->insn_id = BIN(putnil);
+        ((INSN*)last)->operand_size = 0;
     }
     ADD_LABEL(ret, end_label);
 }
@@ -5757,7 +6042,7 @@ compile_if(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, int
     end_label = 0;
 
     compile_branch_condition(iseq, cond_seq, node->nd_cond,
-			     then_label, else_label);
+                             then_label, else_label);
 
     ci_size = body->ci_size;
     CHECK(COMPILE_(then_seq, "then", node_body, popped));
@@ -5784,44 +6069,44 @@ compile_if(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, int
     ADD_SEQ(ret, cond_seq);
 
     if (then_label->refcnt && else_label->refcnt) {
-	branches = decl_branch_base(iseq, node, type == NODE_IF ? "if" : "unless");
+        branches = decl_branch_base(iseq, node, type == NODE_IF ? "if" : "unless");
     }
 
     if (then_label->refcnt) {
-	ADD_LABEL(ret, then_label);
-	if (else_label->refcnt) {
-	    add_trace_branch_coverage(
+        ADD_LABEL(ret, then_label);
+        if (else_label->refcnt) {
+            add_trace_branch_coverage(
                 iseq,
-		ret,
+                ret,
                 node_body ? node_body : node,
                 0,
-		type == NODE_IF ? "then" : "else",
-		branches);
-	    end_label = NEW_LABEL(line);
-	    ADD_INSNL(then_seq, line_node, jump, end_label);
+                type == NODE_IF ? "then" : "else",
+                branches);
+            end_label = NEW_LABEL(line);
+            ADD_INSNL(then_seq, line_node, jump, end_label);
             if (!popped) {
                 ADD_INSN(then_seq, line_node, pop);
             }
-	}
-	ADD_SEQ(ret, then_seq);
+        }
+        ADD_SEQ(ret, then_seq);
     }
 
     if (else_label->refcnt) {
-	ADD_LABEL(ret, else_label);
-	if (then_label->refcnt) {
-	    add_trace_branch_coverage(
+        ADD_LABEL(ret, else_label);
+        if (then_label->refcnt) {
+            add_trace_branch_coverage(
                 iseq,
-		ret,
+                ret,
                 node_else ? node_else : node,
                 1,
-		type == NODE_IF ? "else" : "then",
-		branches);
-	}
-	ADD_SEQ(ret, else_seq);
+                type == NODE_IF ? "else" : "then",
+                branches);
+        }
+        ADD_SEQ(ret, else_seq);
     }
 
     if (end_label) {
-	ADD_LABEL(ret, end_label);
+        ADD_LABEL(ret, end_label);
     }
 
     return COMPILE_OK;
@@ -5866,74 +6151,74 @@ compile_case(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const orig_nod
     ADD_SEQ(ret, head);	/* case VAL */
 
     while (type == NODE_WHEN) {
-	LABEL *l1;
+        LABEL *l1;
 
-	l1 = NEW_LABEL(line);
-	ADD_LABEL(body_seq, l1);
-	ADD_INSN(body_seq, line_node, pop);
-	add_trace_branch_coverage(
+        l1 = NEW_LABEL(line);
+        ADD_LABEL(body_seq, l1);
+        ADD_INSN(body_seq, line_node, pop);
+        add_trace_branch_coverage(
                 iseq,
-		body_seq,
+                body_seq,
                 node->nd_body ? node->nd_body : node,
                 branch_id++,
-		"when",
-		branches);
-	CHECK(COMPILE_(body_seq, "when body", node->nd_body, popped));
-	ADD_INSNL(body_seq, line_node, jump, endlabel);
-
-	vals = node->nd_head;
-	if (vals) {
-	    switch (nd_type(vals)) {
-	      case NODE_LIST:
-		only_special_literals = when_vals(iseq, cond_seq, vals, l1, only_special_literals, literals);
-		if (only_special_literals < 0) return COMPILE_NG;
-		break;
-	      case NODE_SPLAT:
-	      case NODE_ARGSCAT:
-	      case NODE_ARGSPUSH:
-		only_special_literals = 0;
-		CHECK(when_splat_vals(iseq, cond_seq, vals, l1, only_special_literals, literals));
-		break;
-	      default:
-		UNKNOWN_NODE("NODE_CASE", vals, COMPILE_NG);
-	    }
-	}
-	else {
-	    EXPECT_NODE_NONULL("NODE_CASE", node, NODE_LIST, COMPILE_NG);
-	}
-
-	node = node->nd_next;
-	if (!node) {
-	    break;
-	}
-	type = nd_type(node);
-	line = nd_line(node);
+                "when",
+                branches);
+        CHECK(COMPILE_(body_seq, "when body", node->nd_body, popped));
+        ADD_INSNL(body_seq, line_node, jump, endlabel);
+
+        vals = node->nd_head;
+        if (vals) {
+            switch (nd_type(vals)) {
+              case NODE_LIST:
+                only_special_literals = when_vals(iseq, cond_seq, vals, l1, only_special_literals, literals);
+                if (only_special_literals < 0) return COMPILE_NG;
+                break;
+              case NODE_SPLAT:
+              case NODE_ARGSCAT:
+              case NODE_ARGSPUSH:
+                only_special_literals = 0;
+                CHECK(when_splat_vals(iseq, cond_seq, vals, l1, only_special_literals, literals));
+                break;
+              default:
+                UNKNOWN_NODE("NODE_CASE", vals, COMPILE_NG);
+            }
+        }
+        else {
+            EXPECT_NODE_NONULL("NODE_CASE", node, NODE_LIST, COMPILE_NG);
+        }
+
+        node = node->nd_next;
+        if (!node) {
+            break;
+        }
+        type = nd_type(node);
+        line = nd_line(node);
         line_node = node;
     }
     /* else */
     if (node) {
-	ADD_LABEL(cond_seq, elselabel);
-	ADD_INSN(cond_seq, line_node, pop);
-	add_trace_branch_coverage(iseq, cond_seq, node, branch_id, "else", branches);
-	CHECK(COMPILE_(cond_seq, "else", node, popped));
-	ADD_INSNL(cond_seq, line_node, jump, endlabel);
+        ADD_LABEL(cond_seq, elselabel);
+        ADD_INSN(cond_seq, line_node, pop);
+        add_trace_branch_coverage(iseq, cond_seq, node, branch_id, "else", branches);
+        CHECK(COMPILE_(cond_seq, "else", node, popped));
+        ADD_INSNL(cond_seq, line_node, jump, endlabel);
     }
     else {
-	debugs("== else (implicit)\n");
-	ADD_LABEL(cond_seq, elselabel);
-	ADD_INSN(cond_seq, orig_node, pop);
-	add_trace_branch_coverage(iseq, cond_seq, orig_node, branch_id, "else", branches);
-	if (!popped) {
-	    ADD_INSN(cond_seq, orig_node, putnil);
-	}
-	ADD_INSNL(cond_seq, orig_node, jump, endlabel);
+        debugs("== else (implicit)\n");
+        ADD_LABEL(cond_seq, elselabel);
+        ADD_INSN(cond_seq, orig_node, pop);
+        add_trace_branch_coverage(iseq, cond_seq, orig_node, branch_id, "else", branches);
+        if (!popped) {
+            ADD_INSN(cond_seq, orig_node, putnil);
+        }
+        ADD_INSNL(cond_seq, orig_node, jump, endlabel);
     }
 
     if (only_special_literals && ISEQ_COMPILE_DATA(iseq)->option->specialized_instruction) {
-	ADD_INSN(ret, orig_node, dup);
-	ADD_INSN2(ret, orig_node, opt_case_dispatch, literals, elselabel);
+        ADD_INSN(ret, orig_node, dup);
+        ADD_INSN2(ret, orig_node, opt_case_dispatch, literals, elselabel);
         RB_OBJ_WRITTEN(iseq, Qundef, literals);
-	LABEL_REF(elselabel);
+        LABEL_REF(elselabel);
     }
 
     ADD_SEQ(ret, cond_seq);
@@ -5959,56 +6244,56 @@ compile_case2(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const orig_no
     endlabel = NEW_LABEL(nd_line(node));
 
     while (node && nd_type_p(node, NODE_WHEN)) {
-	const int line = nd_line(node);
-	LABEL *l1 = NEW_LABEL(line);
-	ADD_LABEL(body_seq, l1);
-	add_trace_branch_coverage(
+        const int line = nd_line(node);
+        LABEL *l1 = NEW_LABEL(line);
+        ADD_LABEL(body_seq, l1);
+        add_trace_branch_coverage(
                 iseq,
-		body_seq,
-		node->nd_body ? node->nd_body : node,
+                body_seq,
+                node->nd_body ? node->nd_body : node,
                 branch_id++,
-		"when",
-		branches);
-	CHECK(COMPILE_(body_seq, "when", node->nd_body, popped));
-	ADD_INSNL(body_seq, node, jump, endlabel);
+                "when",
+                branches);
+        CHECK(COMPILE_(body_seq, "when", node->nd_body, popped));
+        ADD_INSNL(body_seq, node, jump, endlabel);
 
-	vals = node->nd_head;
-	if (!vals) {
+        vals = node->nd_head;
+        if (!vals) {
             EXPECT_NODE_NONULL("NODE_WHEN", node, NODE_LIST, COMPILE_NG);
-	}
-	switch (nd_type(vals)) {
-	  case NODE_LIST:
-	    while (vals) {
-		LABEL *lnext;
-		val = vals->nd_head;
-		lnext = NEW_LABEL(nd_line(val));
-		debug_compile("== when2\n", (void)0);
-		CHECK(compile_branch_condition(iseq, ret, val, l1, lnext));
-		ADD_LABEL(ret, lnext);
-		vals = vals->nd_next;
-	    }
-	    break;
-	  case NODE_SPLAT:
-	  case NODE_ARGSCAT:
-	  case NODE_ARGSPUSH:
-	    ADD_INSN(ret, vals, putnil);
-	    CHECK(COMPILE(ret, "when2/cond splat", vals));
-	    ADD_INSN1(ret, vals, checkmatch, INT2FIX(VM_CHECKMATCH_TYPE_WHEN | VM_CHECKMATCH_ARRAY));
-	    ADD_INSNL(ret, vals, branchif, l1);
-	    break;
-	  default:
-	    UNKNOWN_NODE("NODE_WHEN", vals, COMPILE_NG);
-	}
-	node = node->nd_next;
+        }
+        switch (nd_type(vals)) {
+          case NODE_LIST:
+            while (vals) {
+                LABEL *lnext;
+                val = vals->nd_head;
+                lnext = NEW_LABEL(nd_line(val));
+                debug_compile("== when2\n", (void)0);
+                CHECK(compile_branch_condition(iseq, ret, val, l1, lnext));
+                ADD_LABEL(ret, lnext);
+                vals = vals->nd_next;
+            }
+            break;
+          case NODE_SPLAT:
+          case NODE_ARGSCAT:
+          case NODE_ARGSPUSH:
+            ADD_INSN(ret, vals, putnil);
+            CHECK(COMPILE(ret, "when2/cond splat", vals));
+            ADD_INSN1(ret, vals, checkmatch, INT2FIX(VM_CHECKMATCH_TYPE_WHEN | VM_CHECKMATCH_ARRAY));
+            ADD_INSNL(ret, vals, branchif, l1);
+            break;
+          default:
+            UNKNOWN_NODE("NODE_WHEN", vals, COMPILE_NG);
+        }
+        node = node->nd_next;
     }
     /* else */
     add_trace_branch_coverage(
         iseq,
-	ret,
+        ret,
         node ? node : orig_node,
         branch_id,
-	"else",
-	branches);
+        "else",
+        branches);
     CHECK(COMPILE_(ret, "else", node, popped));
     ADD_INSNL(ret, orig_node, jump, endlabel);
 
@@ -7126,11 +7411,11 @@ compile_loop(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, in
     push_ensure_entry(iseq, &enl, NULL, NULL);
 
     if (node->nd_state == 1) {
-	ADD_INSNL(ret, line_node, jump, next_label);
+        ADD_INSNL(ret, line_node, jump, next_label);
     }
     else {
-	tmp_label = NEW_LABEL(line);
-	ADD_INSNL(ret, line_node, jump, tmp_label);
+        tmp_label = NEW_LABEL(line);
+        ADD_INSNL(ret, line_node, jump, tmp_label);
     }
     ADD_LABEL(ret, adjust_label);
     ADD_INSN(ret, line_node, putnil);
@@ -7143,48 +7428,48 @@ compile_loop(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, in
     branches = decl_branch_base(iseq, node, type == NODE_WHILE ? "while" : "until");
     add_trace_branch_coverage(
         iseq,
-	ret,
+        ret,
         node->nd_body ? node->nd_body : node,
         0,
-	"body",
-	branches);
+        "body",
+        branches);
     CHECK(COMPILE_POPPED(ret, "while body", node->nd_body));
     ADD_LABEL(ret, next_label);	/* next */
 
     if (type == NODE_WHILE) {
-	compile_branch_condition(iseq, ret, node->nd_cond,
-				 redo_label, end_label);
+        compile_branch_condition(iseq, ret, node->nd_cond,
+                                 redo_label, end_label);
     }
     else {
-	/* until */
-	compile_branch_condition(iseq, ret, node->nd_cond,
-				 end_label, redo_label);
+        /* until */
+        compile_branch_condition(iseq, ret, node->nd_cond,
+                                 end_label, redo_label);
     }
 
     ADD_LABEL(ret, end_label);
     ADD_ADJUST_RESTORE(ret, adjust_label);
 
-    if (node->nd_state == Qundef) {
-	/* ADD_INSN(ret, line_node, putundef); */
-	COMPILE_ERROR(ERROR_ARGS "unsupported: putundef");
-	return COMPILE_NG;
+    if (UNDEF_P(node->nd_state)) {
+        /* ADD_INSN(ret, line_node, putundef); */
+        COMPILE_ERROR(ERROR_ARGS "unsupported: putundef");
+        return COMPILE_NG;
     }
     else {
-	ADD_INSN(ret, line_node, putnil);
+        ADD_INSN(ret, line_node, putnil);
     }
 
     ADD_LABEL(ret, break_label);	/* break */
 
     if (popped) {
-	ADD_INSN(ret, line_node, pop);
+        ADD_INSN(ret, line_node, pop);
     }
 
     ADD_CATCH_ENTRY(CATCH_TYPE_BREAK, redo_label, break_label, NULL,
-		    break_label);
+                    break_label);
     ADD_CATCH_ENTRY(CATCH_TYPE_NEXT, redo_label, break_label, NULL,
-		    next_catch_label);
+                    next_catch_label);
     ADD_CATCH_ENTRY(CATCH_TYPE_REDO, redo_label, break_label, NULL,
-		    ISEQ_COMPILE_DATA(iseq)->redo_label);
+                    ISEQ_COMPILE_DATA(iseq)->redo_label);
 
     ISEQ_COMPILE_DATA(iseq)->start_label = prev_start_label;
     ISEQ_COMPILE_DATA(iseq)->end_label = prev_end_label;
@@ -7206,23 +7491,46 @@ compile_iter(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, in
 
     ADD_LABEL(ret, retry_label);
     if (nd_type_p(node, NODE_FOR)) {
-	CHECK(COMPILE(ret, "iter caller (for)", node->nd_iter));
+        CHECK(COMPILE(ret, "iter caller (for)", node->nd_iter));
 
-	ISEQ_COMPILE_DATA(iseq)->current_block = child_iseq =
-	    NEW_CHILD_ISEQ(node->nd_body, make_name_for_block(iseq),
-			   ISEQ_TYPE_BLOCK, line);
-	ADD_SEND_WITH_BLOCK(ret, line_node, idEach, INT2FIX(0), child_iseq);
+        ISEQ_COMPILE_DATA(iseq)->current_block = child_iseq =
+            NEW_CHILD_ISEQ(node->nd_body, make_name_for_block(iseq),
+                           ISEQ_TYPE_BLOCK, line);
+        ADD_SEND_WITH_BLOCK(ret, line_node, idEach, INT2FIX(0), child_iseq);
     }
     else {
-	ISEQ_COMPILE_DATA(iseq)->current_block = child_iseq =
-	    NEW_CHILD_ISEQ(node->nd_body, make_name_for_block(iseq),
-			   ISEQ_TYPE_BLOCK, line);
-	CHECK(COMPILE(ret, "iter caller", node->nd_iter));
+        ISEQ_COMPILE_DATA(iseq)->current_block = child_iseq =
+            NEW_CHILD_ISEQ(node->nd_body, make_name_for_block(iseq),
+                           ISEQ_TYPE_BLOCK, line);
+        CHECK(COMPILE(ret, "iter caller", node->nd_iter));
+    }
+
+    {
+        // We need to put the label "retry_end_l" immediately after the last "send" instruction.
+        // This because vm_throw checks if the break cont is equal to the index of next insn of the "send".
+        // (Otherwise, it is considered "break from proc-closure". See "TAG_BREAK" handling in "vm_throw_start".)
+        //
+        // Normally, "send" instruction is at the last.
+        // However, qcall under branch coverage measurement adds some instructions after the "send".
+        //
+        // Note that "invokesuper" appears instead of "send".
+        INSN *iobj;
+        LINK_ELEMENT *last_elem = LAST_ELEMENT(ret);
+        iobj = IS_INSN(last_elem) ? (INSN*) last_elem : (INSN*) get_prev_insn((INSN*) last_elem);
+        while (INSN_OF(iobj) != BIN(send) && INSN_OF(iobj) != BIN(invokesuper)) {
+            iobj = (INSN*) get_prev_insn(iobj);
+        }
+        ELEM_INSERT_NEXT(&iobj->link, (LINK_ELEMENT*) retry_end_l);
+
+        // LINK_ANCHOR has a pointer to the last element, but ELEM_INSERT_NEXT does not update it
+        // even if we add an insn to the last of LINK_ANCHOR. So this updates it manually.
+        if (&iobj->link == LAST_ELEMENT(ret)) {
+            ret->last = (LINK_ELEMENT*) retry_end_l;
+        }
     }
-    ADD_LABEL(ret, retry_end_l);
 
     if (popped) {
-	ADD_INSN(ret, line_node, pop);
+        ADD_INSN(ret, line_node, pop);
     }
 
     ISEQ_COMPILE_DATA(iseq)->current_block = prevblock;
@@ -7269,39 +7577,39 @@ compile_break(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, i
     unsigned long throw_flag = 0;
 
     if (ISEQ_COMPILE_DATA(iseq)->redo_label != 0 && can_add_ensure_iseq(iseq)) {
-	/* while/until */
-	LABEL *splabel = NEW_LABEL(0);
-	ADD_LABEL(ret, splabel);
-	ADD_ADJUST(ret, line_node, ISEQ_COMPILE_DATA(iseq)->redo_label);
-	CHECK(COMPILE_(ret, "break val (while/until)", node->nd_stts,
-		       ISEQ_COMPILE_DATA(iseq)->loopval_popped));
-	add_ensure_iseq(ret, iseq, 0);
-	ADD_INSNL(ret, line_node, jump, ISEQ_COMPILE_DATA(iseq)->end_label);
-	ADD_ADJUST_RESTORE(ret, splabel);
-
-	if (!popped) {
-	    ADD_INSN(ret, line_node, putnil);
-	}
+        /* while/until */
+        LABEL *splabel = NEW_LABEL(0);
+        ADD_LABEL(ret, splabel);
+        ADD_ADJUST(ret, line_node, ISEQ_COMPILE_DATA(iseq)->redo_label);
+        CHECK(COMPILE_(ret, "break val (while/until)", node->nd_stts,
+                       ISEQ_COMPILE_DATA(iseq)->loopval_popped));
+        add_ensure_iseq(ret, iseq, 0);
+        ADD_INSNL(ret, line_node, jump, ISEQ_COMPILE_DATA(iseq)->end_label);
+        ADD_ADJUST_RESTORE(ret, splabel);
+
+        if (!popped) {
+            ADD_INSN(ret, line_node, putnil);
+        }
     }
     else {
         const rb_iseq_t *ip = iseq;
 
-	while (ip) {
-	    if (!ISEQ_COMPILE_DATA(ip)) {
-		ip = 0;
-		break;
-	    }
+        while (ip) {
+            if (!ISEQ_COMPILE_DATA(ip)) {
+                ip = 0;
+                break;
+            }
 
-	    if (ISEQ_COMPILE_DATA(ip)->redo_label != 0) {
+            if (ISEQ_COMPILE_DATA(ip)->redo_label != 0) {
                 throw_flag = VM_THROW_NO_ESCAPE_FLAG;
-	    }
+            }
             else if (ISEQ_BODY(ip)->type == ISEQ_TYPE_BLOCK) {
                 throw_flag = 0;
-	    }
+            }
             else if (ISEQ_BODY(ip)->type == ISEQ_TYPE_EVAL) {
                 COMPILE_ERROR(ERROR_ARGS "Can't escape from eval with break");
                 return COMPILE_NG;
-	    }
+            }
             else {
                 ip = ISEQ_BODY(ip)->parent_iseq;
                 continue;
@@ -7314,9 +7622,9 @@ compile_break(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, i
                 ADD_INSN(ret, line_node, pop);
             }
             return COMPILE_OK;
-	}
-	COMPILE_ERROR(ERROR_ARGS "Invalid break");
-	return COMPILE_NG;
+        }
+        COMPILE_ERROR(ERROR_ARGS "Invalid break");
+        return COMPILE_NG;
     }
     return COMPILE_OK;
 }
@@ -7328,69 +7636,68 @@ compile_next(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, in
     unsigned long throw_flag = 0;
 
     if (ISEQ_COMPILE_DATA(iseq)->redo_label != 0 && can_add_ensure_iseq(iseq)) {
-	LABEL *splabel = NEW_LABEL(0);
-	debugs("next in while loop\n");
-	ADD_LABEL(ret, splabel);
-	CHECK(COMPILE(ret, "next val/valid syntax?", node->nd_stts));
-	add_ensure_iseq(ret, iseq, 0);
-	ADD_ADJUST(ret, line_node, ISEQ_COMPILE_DATA(iseq)->redo_label);
-	ADD_INSNL(ret, line_node, jump, ISEQ_COMPILE_DATA(iseq)->start_label);
-	ADD_ADJUST_RESTORE(ret, splabel);
-	if (!popped) {
-	    ADD_INSN(ret, line_node, putnil);
-	}
+        LABEL *splabel = NEW_LABEL(0);
+        debugs("next in while loop\n");
+        ADD_LABEL(ret, splabel);
+        CHECK(COMPILE(ret, "next val/valid syntax?", node->nd_stts));
+        add_ensure_iseq(ret, iseq, 0);
+        ADD_ADJUST(ret, line_node, ISEQ_COMPILE_DATA(iseq)->redo_label);
+        ADD_INSNL(ret, line_node, jump, ISEQ_COMPILE_DATA(iseq)->start_label);
+        ADD_ADJUST_RESTORE(ret, splabel);
+        if (!popped) {
+            ADD_INSN(ret, line_node, putnil);
+        }
     }
     else if (ISEQ_COMPILE_DATA(iseq)->end_label && can_add_ensure_iseq(iseq)) {
-	LABEL *splabel = NEW_LABEL(0);
-	debugs("next in block\n");
-	ADD_LABEL(ret, splabel);
-	ADD_ADJUST(ret, line_node, ISEQ_COMPILE_DATA(iseq)->start_label);
-	CHECK(COMPILE(ret, "next val", node->nd_stts));
-	add_ensure_iseq(ret, iseq, 0);
-	ADD_INSNL(ret, line_node, jump, ISEQ_COMPILE_DATA(iseq)->end_label);
-	ADD_ADJUST_RESTORE(ret, splabel);
-	splabel->unremovable = FALSE;
-
-	if (!popped) {
-	    ADD_INSN(ret, line_node, putnil);
-	}
+        LABEL *splabel = NEW_LABEL(0);
+        debugs("next in block\n");
+        ADD_LABEL(ret, splabel);
+        ADD_ADJUST(ret, line_node, ISEQ_COMPILE_DATA(iseq)->start_label);
+        CHECK(COMPILE(ret, "next val", node->nd_stts));
+        add_ensure_iseq(ret, iseq, 0);
+        ADD_INSNL(ret, line_node, jump, ISEQ_COMPILE_DATA(iseq)->end_label);
+        ADD_ADJUST_RESTORE(ret, splabel);
+
+        if (!popped) {
+            ADD_INSN(ret, line_node, putnil);
+        }
     }
     else {
-	const rb_iseq_t *ip = iseq;
+        const rb_iseq_t *ip = iseq;
 
-	while (ip) {
-	    if (!ISEQ_COMPILE_DATA(ip)) {
-		ip = 0;
-		break;
-	    }
+        while (ip) {
+            if (!ISEQ_COMPILE_DATA(ip)) {
+                ip = 0;
+                break;
+            }
 
             throw_flag = VM_THROW_NO_ESCAPE_FLAG;
-	    if (ISEQ_COMPILE_DATA(ip)->redo_label != 0) {
-		/* while loop */
-		break;
-	    }
+            if (ISEQ_COMPILE_DATA(ip)->redo_label != 0) {
+                /* while loop */
+                break;
+            }
             else if (ISEQ_BODY(ip)->type == ISEQ_TYPE_BLOCK) {
-		break;
-	    }
+                break;
+            }
             else if (ISEQ_BODY(ip)->type == ISEQ_TYPE_EVAL) {
                 COMPILE_ERROR(ERROR_ARGS "Can't escape from eval with next");
                 return COMPILE_NG;
-	    }
+            }
 
             ip = ISEQ_BODY(ip)->parent_iseq;
-	}
-	if (ip != 0) {
-	    CHECK(COMPILE(ret, "next val", node->nd_stts));
+        }
+        if (ip != 0) {
+            CHECK(COMPILE(ret, "next val", node->nd_stts));
             ADD_INSN1(ret, line_node, throw, INT2FIX(throw_flag | TAG_NEXT));
 
-	    if (popped) {
-		ADD_INSN(ret, line_node, pop);
-	    }
-	}
-	else {
-	    COMPILE_ERROR(ERROR_ARGS "Invalid next");
-	    return COMPILE_NG;
-	}
+            if (popped) {
+                ADD_INSN(ret, line_node, pop);
+            }
+        }
+        else {
+            COMPILE_ERROR(ERROR_ARGS "Invalid next");
+            return COMPILE_NG;
+        }
     }
     return COMPILE_OK;
 }
@@ -7401,65 +7708,65 @@ compile_redo(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, in
     const NODE *line_node = node;
 
     if (ISEQ_COMPILE_DATA(iseq)->redo_label && can_add_ensure_iseq(iseq)) {
-	LABEL *splabel = NEW_LABEL(0);
-	debugs("redo in while");
-	ADD_LABEL(ret, splabel);
-	ADD_ADJUST(ret, line_node, ISEQ_COMPILE_DATA(iseq)->redo_label);
-	add_ensure_iseq(ret, iseq, 0);
-	ADD_INSNL(ret, line_node, jump, ISEQ_COMPILE_DATA(iseq)->redo_label);
-	ADD_ADJUST_RESTORE(ret, splabel);
-	if (!popped) {
-	    ADD_INSN(ret, line_node, putnil);
-	}
+        LABEL *splabel = NEW_LABEL(0);
+        debugs("redo in while");
+        ADD_LABEL(ret, splabel);
+        ADD_ADJUST(ret, line_node, ISEQ_COMPILE_DATA(iseq)->redo_label);
+        add_ensure_iseq(ret, iseq, 0);
+        ADD_INSNL(ret, line_node, jump, ISEQ_COMPILE_DATA(iseq)->redo_label);
+        ADD_ADJUST_RESTORE(ret, splabel);
+        if (!popped) {
+            ADD_INSN(ret, line_node, putnil);
+        }
     }
     else if (ISEQ_BODY(iseq)->type != ISEQ_TYPE_EVAL && ISEQ_COMPILE_DATA(iseq)->start_label && can_add_ensure_iseq(iseq)) {
-	LABEL *splabel = NEW_LABEL(0);
+        LABEL *splabel = NEW_LABEL(0);
 
-	debugs("redo in block");
-	ADD_LABEL(ret, splabel);
-	add_ensure_iseq(ret, iseq, 0);
-	ADD_ADJUST(ret, line_node, ISEQ_COMPILE_DATA(iseq)->start_label);
-	ADD_INSNL(ret, line_node, jump, ISEQ_COMPILE_DATA(iseq)->start_label);
-	ADD_ADJUST_RESTORE(ret, splabel);
+        debugs("redo in block");
+        ADD_LABEL(ret, splabel);
+        add_ensure_iseq(ret, iseq, 0);
+        ADD_ADJUST(ret, line_node, ISEQ_COMPILE_DATA(iseq)->start_label);
+        ADD_INSNL(ret, line_node, jump, ISEQ_COMPILE_DATA(iseq)->start_label);
+        ADD_ADJUST_RESTORE(ret, splabel);
 
-	if (!popped) {
-	    ADD_INSN(ret, line_node, putnil);
-	}
+        if (!popped) {
+            ADD_INSN(ret, line_node, putnil);
+        }
     }
     else {
-	const rb_iseq_t *ip = iseq;
+        const rb_iseq_t *ip = iseq;
 
-	while (ip) {
-	    if (!ISEQ_COMPILE_DATA(ip)) {
-		ip = 0;
-		break;
-	    }
+        while (ip) {
+            if (!ISEQ_COMPILE_DATA(ip)) {
+                ip = 0;
+                break;
+            }
 
-	    if (ISEQ_COMPILE_DATA(ip)->redo_label != 0) {
-		break;
-	    }
+            if (ISEQ_COMPILE_DATA(ip)->redo_label != 0) {
+                break;
+            }
             else if (ISEQ_BODY(ip)->type == ISEQ_TYPE_BLOCK) {
-		break;
-	    }
+                break;
+            }
             else if (ISEQ_BODY(ip)->type == ISEQ_TYPE_EVAL) {
                 COMPILE_ERROR(ERROR_ARGS "Can't escape from eval with redo");
                 return COMPILE_NG;
-	    }
+            }
 
             ip = ISEQ_BODY(ip)->parent_iseq;
-	}
-	if (ip != 0) {
-	    ADD_INSN(ret, line_node, putnil);
+        }
+        if (ip != 0) {
+            ADD_INSN(ret, line_node, putnil);
             ADD_INSN1(ret, line_node, throw, INT2FIX(VM_THROW_NO_ESCAPE_FLAG | TAG_REDO));
 
-	    if (popped) {
-		ADD_INSN(ret, line_node, pop);
-	    }
-	}
-	else {
-	    COMPILE_ERROR(ERROR_ARGS "Invalid redo");
-	    return COMPILE_NG;
-	}
+            if (popped) {
+                ADD_INSN(ret, line_node, pop);
+            }
+        }
+        else {
+            COMPILE_ERROR(ERROR_ARGS "Invalid redo");
+            return COMPILE_NG;
+        }
     }
     return COMPILE_OK;
 }
@@ -7470,16 +7777,16 @@ compile_retry(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, i
     const NODE *line_node = node;
 
     if (ISEQ_BODY(iseq)->type == ISEQ_TYPE_RESCUE) {
-	ADD_INSN(ret, line_node, putnil);
-	ADD_INSN1(ret, line_node, throw, INT2FIX(TAG_RETRY));
+        ADD_INSN(ret, line_node, putnil);
+        ADD_INSN1(ret, line_node, throw, INT2FIX(TAG_RETRY));
 
-	if (popped) {
-	    ADD_INSN(ret, line_node, pop);
-	}
+        if (popped) {
+            ADD_INSN(ret, line_node, pop);
+        }
     }
     else {
-	COMPILE_ERROR(ERROR_ARGS "Invalid retry");
-	return COMPILE_NG;
+        COMPILE_ERROR(ERROR_ARGS "Invalid retry");
+        return COMPILE_NG;
     }
     return COMPILE_OK;
 }
@@ -7510,14 +7817,14 @@ compile_rescue(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node,
 
     ADD_LABEL(ret, lend);
     if (node->nd_else) {
-	ADD_INSN(ret, line_node, pop);
-	CHECK(COMPILE(ret, "rescue else", node->nd_else));
+        ADD_INSN(ret, line_node, pop);
+        CHECK(COMPILE(ret, "rescue else", node->nd_else));
     }
     ADD_INSN(ret, line_node, nop);
     ADD_LABEL(ret, lcont);
 
     if (popped) {
-	ADD_INSN(ret, line_node, pop);
+        ADD_INSN(ret, line_node, pop);
     }
 
     /* register catch entry */
@@ -7536,48 +7843,48 @@ compile_resbody(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node,
     LABEL *label_miss, *label_hit;
 
     while (resq) {
-	label_miss = NEW_LABEL(line);
-	label_hit = NEW_LABEL(line);
-
-	narg = resq->nd_args;
-	if (narg) {
-	    switch (nd_type(narg)) {
-	      case NODE_LIST:
-		while (narg) {
-		    ADD_GETLOCAL(ret, line_node, LVAR_ERRINFO, 0);
-		    CHECK(COMPILE(ret, "rescue arg", narg->nd_head));
-		    ADD_INSN1(ret, line_node, checkmatch, INT2FIX(VM_CHECKMATCH_TYPE_RESCUE));
-		    ADD_INSNL(ret, line_node, branchif, label_hit);
-		    narg = narg->nd_next;
-		}
-		break;
-	      case NODE_SPLAT:
-	      case NODE_ARGSCAT:
-	      case NODE_ARGSPUSH:
-		ADD_GETLOCAL(ret, line_node, LVAR_ERRINFO, 0);
-		CHECK(COMPILE(ret, "rescue/cond splat", narg));
-		ADD_INSN1(ret, line_node, checkmatch, INT2FIX(VM_CHECKMATCH_TYPE_RESCUE | VM_CHECKMATCH_ARRAY));
-		ADD_INSNL(ret, line_node, branchif, label_hit);
-		break;
-	      default:
-		UNKNOWN_NODE("NODE_RESBODY", narg, COMPILE_NG);
-	    }
-	}
-	else {
-	    ADD_GETLOCAL(ret, line_node, LVAR_ERRINFO, 0);
-	    ADD_INSN1(ret, line_node, putobject, rb_eStandardError);
-	    ADD_INSN1(ret, line_node, checkmatch, INT2FIX(VM_CHECKMATCH_TYPE_RESCUE));
-	    ADD_INSNL(ret, line_node, branchif, label_hit);
-	}
-	ADD_INSNL(ret, line_node, jump, label_miss);
-	ADD_LABEL(ret, label_hit);
-	CHECK(COMPILE(ret, "resbody body", resq->nd_body));
-	if (ISEQ_COMPILE_DATA(iseq)->option->tailcall_optimization) {
-	    ADD_INSN(ret, line_node, nop);
-	}
-	ADD_INSN(ret, line_node, leave);
-	ADD_LABEL(ret, label_miss);
-	resq = resq->nd_head;
+        label_miss = NEW_LABEL(line);
+        label_hit = NEW_LABEL(line);
+
+        narg = resq->nd_args;
+        if (narg) {
+            switch (nd_type(narg)) {
+              case NODE_LIST:
+                while (narg) {
+                    ADD_GETLOCAL(ret, line_node, LVAR_ERRINFO, 0);
+                    CHECK(COMPILE(ret, "rescue arg", narg->nd_head));
+                    ADD_INSN1(ret, line_node, checkmatch, INT2FIX(VM_CHECKMATCH_TYPE_RESCUE));
+                    ADD_INSNL(ret, line_node, branchif, label_hit);
+                    narg = narg->nd_next;
+                }
+                break;
+              case NODE_SPLAT:
+              case NODE_ARGSCAT:
+              case NODE_ARGSPUSH:
+                ADD_GETLOCAL(ret, line_node, LVAR_ERRINFO, 0);
+                CHECK(COMPILE(ret, "rescue/cond splat", narg));
+                ADD_INSN1(ret, line_node, checkmatch, INT2FIX(VM_CHECKMATCH_TYPE_RESCUE | VM_CHECKMATCH_ARRAY));
+                ADD_INSNL(ret, line_node, branchif, label_hit);
+                break;
+              default:
+                UNKNOWN_NODE("NODE_RESBODY", narg, COMPILE_NG);
+            }
+        }
+        else {
+            ADD_GETLOCAL(ret, line_node, LVAR_ERRINFO, 0);
+            ADD_INSN1(ret, line_node, putobject, rb_eStandardError);
+            ADD_INSN1(ret, line_node, checkmatch, INT2FIX(VM_CHECKMATCH_TYPE_RESCUE));
+            ADD_INSNL(ret, line_node, branchif, label_hit);
+        }
+        ADD_INSNL(ret, line_node, jump, label_miss);
+        ADD_LABEL(ret, label_hit);
+        CHECK(COMPILE(ret, "resbody body", resq->nd_body));
+        if (ISEQ_COMPILE_DATA(iseq)->option->tailcall_optimization) {
+            ADD_INSN(ret, line_node, nop);
+        }
+        ADD_INSN(ret, line_node, leave);
+        ADD_LABEL(ret, label_miss);
+        resq = resq->nd_head;
     }
     return COMPILE_OK;
 }
@@ -7590,7 +7897,7 @@ compile_ensure(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node,
     DECL_ANCHOR(ensr);
     const rb_iseq_t *ensure = NEW_CHILD_ISEQ(node->nd_ensr,
                                              rb_str_concat(rb_str_new2 ("ensure in "), ISEQ_BODY(iseq)->location.label),
-					     ISEQ_TYPE_ENSURE, line);
+                                             ISEQ_TYPE_ENSURE, line);
     LABEL *lstart = NEW_LABEL(line);
     LABEL *lend = NEW_LABEL(line);
     LABEL *lcont = NEW_LABEL(line);
@@ -7620,11 +7927,11 @@ compile_ensure(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node,
 
     erange = ISEQ_COMPILE_DATA(iseq)->ensure_node_stack->erange;
     if (lstart->link.next != &lend->link) {
-	while (erange) {
-	    ADD_CATCH_ENTRY(CATCH_TYPE_ENSURE, erange->begin, erange->end,
-			    ensure, lcont);
-	    erange = erange->next;
-	}
+        while (erange) {
+            ADD_CATCH_ENTRY(CATCH_TYPE_ENSURE, erange->begin, erange->end,
+                            ensure, lcont);
+            erange = erange->next;
+        }
     }
 
     ISEQ_COMPILE_DATA(iseq)->ensure_node_stack = enl.prev;
@@ -7637,55 +7944,55 @@ compile_return(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node,
     const NODE *line_node = node;
 
     if (iseq) {
-        enum iseq_type type = ISEQ_BODY(iseq)->type;
-	const rb_iseq_t *is = iseq;
-	enum iseq_type t = type;
-	const NODE *retval = node->nd_stts;
-	LABEL *splabel = 0;
+        enum rb_iseq_type type = ISEQ_BODY(iseq)->type;
+        const rb_iseq_t *is = iseq;
+        enum rb_iseq_type t = type;
+        const NODE *retval = node->nd_stts;
+        LABEL *splabel = 0;
 
-	while (t == ISEQ_TYPE_RESCUE || t == ISEQ_TYPE_ENSURE) {
+        while (t == ISEQ_TYPE_RESCUE || t == ISEQ_TYPE_ENSURE) {
             if (!(is = ISEQ_BODY(is)->parent_iseq)) break;
             t = ISEQ_BODY(is)->type;
-	}
-	switch (t) {
-	  case ISEQ_TYPE_TOP:
-	  case ISEQ_TYPE_MAIN:
+        }
+        switch (t) {
+          case ISEQ_TYPE_TOP:
+          case ISEQ_TYPE_MAIN:
             if (retval) {
                 rb_warn("argument of top-level return is ignored");
             }
-	    if (is == iseq) {
-		/* plain top-level, leave directly */
-		type = ISEQ_TYPE_METHOD;
-	    }
-	    break;
-	  default:
-	    break;
-	}
-
-	if (type == ISEQ_TYPE_METHOD) {
-	    splabel = NEW_LABEL(0);
-	    ADD_LABEL(ret, splabel);
-	    ADD_ADJUST(ret, line_node, 0);
-	}
-
-	CHECK(COMPILE(ret, "return nd_stts (return val)", retval));
-
-	if (type == ISEQ_TYPE_METHOD && can_add_ensure_iseq(iseq)) {
-	    add_ensure_iseq(ret, iseq, 1);
-	    ADD_TRACE(ret, RUBY_EVENT_RETURN);
-	    ADD_INSN(ret, line_node, leave);
-	    ADD_ADJUST_RESTORE(ret, splabel);
-
-	    if (!popped) {
-		ADD_INSN(ret, line_node, putnil);
-	    }
-	}
-	else {
-	    ADD_INSN1(ret, line_node, throw, INT2FIX(TAG_RETURN));
-	    if (popped) {
-		ADD_INSN(ret, line_node, pop);
-	    }
-	}
+            if (is == iseq) {
+                /* plain top-level, leave directly */
+                type = ISEQ_TYPE_METHOD;
+            }
+            break;
+          default:
+            break;
+        }
+
+        if (type == ISEQ_TYPE_METHOD) {
+            splabel = NEW_LABEL(0);
+            ADD_LABEL(ret, splabel);
+            ADD_ADJUST(ret, line_node, 0);
+        }
+
+        CHECK(COMPILE(ret, "return nd_stts (return val)", retval));
+
+        if (type == ISEQ_TYPE_METHOD && can_add_ensure_iseq(iseq)) {
+            add_ensure_iseq(ret, iseq, 1);
+            ADD_TRACE(ret, RUBY_EVENT_RETURN);
+            ADD_INSN(ret, line_node, leave);
+            ADD_ADJUST_RESTORE(ret, splabel);
+
+            if (!popped) {
+                ADD_INSN(ret, line_node, putnil);
+            }
+        }
+        else {
+            ADD_INSN1(ret, line_node, throw, INT2FIX(TAG_RETURN));
+            if (popped) {
+                ADD_INSN(ret, line_node, pop);
+            }
+        }
     }
     return COMPILE_OK;
 }
@@ -7697,7 +8004,7 @@ compile_evstr(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, i
 
     if (!popped && !all_string_result_p(node)) {
         const NODE *line_node = node;
-	const unsigned int flag = VM_CALL_FCALL;
+        const unsigned int flag = VM_CALL_FCALL;
 
         // Note, this dup could be removed if we are willing to change anytostring. It pops
         // two VALUEs off the stack when it could work by replacing the top most VALUE.
@@ -7992,7 +8299,7 @@ compile_builtin_mandatory_only_method(rb_iseq_t *iseq, const NODE *node, const N
     ISEQ_BODY(iseq)->mandatory_only_iseq =
       rb_iseq_new_with_opt(&ast, rb_iseq_base_label(iseq),
                            rb_iseq_path(iseq), rb_iseq_realpath(iseq),
-                           INT2FIX(nd_line(line_node)), NULL, 0,
+                           nd_line(line_node), NULL, 0,
                            ISEQ_TYPE_METHOD, ISEQ_COMPILE_DATA(iseq)->option);
 
     GET_VM()->builtin_inline_index = prev_inline_index;
@@ -8285,106 +8592,106 @@ compile_op_asgn1(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node
      */
 
     if (!popped) {
-	ADD_INSN(ret, node, putnil);
+        ADD_INSN(ret, node, putnil);
     }
     asgnflag = COMPILE_RECV(ret, "NODE_OP_ASGN1 recv", node);
     CHECK(asgnflag != -1);
     switch (nd_type(node->nd_args->nd_head)) {
       case NODE_ZLIST:
-	argc = INT2FIX(0);
-	break;
+        argc = INT2FIX(0);
+        break;
       case NODE_BLOCK_PASS:
-	boff = 1;
-	/* fall through */
+        boff = 1;
+        /* fall through */
       default:
-	argc = setup_args(iseq, ret, node->nd_args->nd_head, &flag, NULL);
-	CHECK(!NIL_P(argc));
+        argc = setup_args(iseq, ret, node->nd_args->nd_head, &flag, NULL);
+        CHECK(!NIL_P(argc));
     }
     ADD_INSN1(ret, node, dupn, FIXNUM_INC(argc, 1 + boff));
     flag |= asgnflag;
     ADD_SEND_WITH_FLAG(ret, node, idAREF, argc, INT2FIX(flag));
 
     if (id == idOROP || id == idANDOP) {
-	/* a[x] ||= y  or  a[x] &&= y
-
-	   unless/if a[x]
-	   a[x]= y
-	   else
-	   nil
-	   end
-	*/
-	LABEL *label = NEW_LABEL(line);
-	LABEL *lfin = NEW_LABEL(line);
-
-	ADD_INSN(ret, node, dup);
-	if (id == idOROP) {
-	    ADD_INSNL(ret, node, branchif, label);
-	}
-	else { /* idANDOP */
-	    ADD_INSNL(ret, node, branchunless, label);
-	}
-	ADD_INSN(ret, node, pop);
-
-	CHECK(COMPILE(ret, "NODE_OP_ASGN1 args->body: ", node->nd_args->nd_body));
-	if (!popped) {
-	    ADD_INSN1(ret, node, setn, FIXNUM_INC(argc, 2+boff));
-	}
-	if (flag & VM_CALL_ARGS_SPLAT) {
-	    ADD_INSN1(ret, node, newarray, INT2FIX(1));
-	    if (boff > 0) {
-		ADD_INSN1(ret, node, dupn, INT2FIX(3));
-		ADD_INSN(ret, node, swap);
-		ADD_INSN(ret, node, pop);
-	    }
-	    ADD_INSN(ret, node, concatarray);
-	    if (boff > 0) {
-		ADD_INSN1(ret, node, setn, INT2FIX(3));
-		ADD_INSN(ret, node, pop);
-		ADD_INSN(ret, node, pop);
-	    }
-	    ADD_SEND_WITH_FLAG(ret, node, idASET, argc, INT2FIX(flag));
-	}
-	else {
-	    if (boff > 0)
-		ADD_INSN(ret, node, swap);
-	    ADD_SEND_WITH_FLAG(ret, node, idASET, FIXNUM_INC(argc, 1), INT2FIX(flag));
-	}
-	ADD_INSN(ret, node, pop);
-	ADD_INSNL(ret, node, jump, lfin);
-	ADD_LABEL(ret, label);
-	if (!popped) {
-	    ADD_INSN1(ret, node, setn, FIXNUM_INC(argc, 2+boff));
-	}
-	ADD_INSN1(ret, node, adjuststack, FIXNUM_INC(argc, 2+boff));
-	ADD_LABEL(ret, lfin);
+        /* a[x] ||= y  or  a[x] &&= y
+
+           unless/if a[x]
+           a[x]= y
+           else
+           nil
+           end
+        */
+        LABEL *label = NEW_LABEL(line);
+        LABEL *lfin = NEW_LABEL(line);
+
+        ADD_INSN(ret, node, dup);
+        if (id == idOROP) {
+            ADD_INSNL(ret, node, branchif, label);
+        }
+        else { /* idANDOP */
+            ADD_INSNL(ret, node, branchunless, label);
+        }
+        ADD_INSN(ret, node, pop);
+
+        CHECK(COMPILE(ret, "NODE_OP_ASGN1 args->body: ", node->nd_args->nd_body));
+        if (!popped) {
+            ADD_INSN1(ret, node, setn, FIXNUM_INC(argc, 2+boff));
+        }
+        if (flag & VM_CALL_ARGS_SPLAT) {
+            ADD_INSN1(ret, node, newarray, INT2FIX(1));
+            if (boff > 0) {
+                ADD_INSN1(ret, node, dupn, INT2FIX(3));
+                ADD_INSN(ret, node, swap);
+                ADD_INSN(ret, node, pop);
+            }
+            ADD_INSN(ret, node, concatarray);
+            if (boff > 0) {
+                ADD_INSN1(ret, node, setn, INT2FIX(3));
+                ADD_INSN(ret, node, pop);
+                ADD_INSN(ret, node, pop);
+            }
+            ADD_SEND_WITH_FLAG(ret, node, idASET, argc, INT2FIX(flag));
+        }
+        else {
+            if (boff > 0)
+                ADD_INSN(ret, node, swap);
+            ADD_SEND_WITH_FLAG(ret, node, idASET, FIXNUM_INC(argc, 1), INT2FIX(flag));
+        }
+        ADD_INSN(ret, node, pop);
+        ADD_INSNL(ret, node, jump, lfin);
+        ADD_LABEL(ret, label);
+        if (!popped) {
+            ADD_INSN1(ret, node, setn, FIXNUM_INC(argc, 2+boff));
+        }
+        ADD_INSN1(ret, node, adjuststack, FIXNUM_INC(argc, 2+boff));
+        ADD_LABEL(ret, lfin);
     }
     else {
-	CHECK(COMPILE(ret, "NODE_OP_ASGN1 args->body: ", node->nd_args->nd_body));
-	ADD_SEND(ret, node, id, INT2FIX(1));
-	if (!popped) {
-	    ADD_INSN1(ret, node, setn, FIXNUM_INC(argc, 2+boff));
-	}
-	if (flag & VM_CALL_ARGS_SPLAT) {
-	    ADD_INSN1(ret, node, newarray, INT2FIX(1));
-	    if (boff > 0) {
-		ADD_INSN1(ret, node, dupn, INT2FIX(3));
-		ADD_INSN(ret, node, swap);
-		ADD_INSN(ret, node, pop);
-	    }
-	    ADD_INSN(ret, node, concatarray);
-	    if (boff > 0) {
-		ADD_INSN1(ret, node, setn, INT2FIX(3));
-		ADD_INSN(ret, node, pop);
-		ADD_INSN(ret, node, pop);
-	    }
-	    ADD_SEND_WITH_FLAG(ret, node, idASET, argc, INT2FIX(flag));
-	}
-	else {
-	    if (boff > 0)
-		ADD_INSN(ret, node, swap);
-	    ADD_SEND_WITH_FLAG(ret, node, idASET, FIXNUM_INC(argc, 1), INT2FIX(flag));
-	}
-	ADD_INSN(ret, node, pop);
+        CHECK(COMPILE(ret, "NODE_OP_ASGN1 args->body: ", node->nd_args->nd_body));
+        ADD_SEND(ret, node, id, INT2FIX(1));
+        if (!popped) {
+            ADD_INSN1(ret, node, setn, FIXNUM_INC(argc, 2+boff));
+        }
+        if (flag & VM_CALL_ARGS_SPLAT) {
+            ADD_INSN1(ret, node, newarray, INT2FIX(1));
+            if (boff > 0) {
+                ADD_INSN1(ret, node, dupn, INT2FIX(3));
+                ADD_INSN(ret, node, swap);
+                ADD_INSN(ret, node, pop);
+            }
+            ADD_INSN(ret, node, concatarray);
+            if (boff > 0) {
+                ADD_INSN1(ret, node, setn, INT2FIX(3));
+                ADD_INSN(ret, node, pop);
+                ADD_INSN(ret, node, pop);
+            }
+            ADD_SEND_WITH_FLAG(ret, node, idASET, argc, INT2FIX(flag));
+        }
+        else {
+            if (boff > 0)
+                ADD_INSN(ret, node, swap);
+            ADD_SEND_WITH_FLAG(ret, node, idASET, FIXNUM_INC(argc, 1), INT2FIX(flag));
+        }
+        ADD_INSN(ret, node, pop);
     }
     return COMPILE_OK;
 }
@@ -8424,6 +8731,17 @@ compile_op_asgn2(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node
       lfin:       # o ?
       pop       # o
 
+      # or (popped)
+      if lcfin  # r
+      eval v    # r v
+      send a=   # ?
+      jump lfin # ?
+
+      lcfin:      # r
+
+      lfin:       # ?
+      pop       #
+
       # and
       dup       # r o o
       unless lcfin
@@ -8444,56 +8762,56 @@ compile_op_asgn2(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node
     asgnflag = COMPILE_RECV(ret, "NODE_OP_ASGN2#recv", node);
     CHECK(asgnflag != -1);
     if (node->nd_next->nd_aid) {
-	lskip = NEW_LABEL(line);
-	ADD_INSN(ret, node, dup);
-	ADD_INSNL(ret, node, branchnil, lskip);
+        lskip = NEW_LABEL(line);
+        ADD_INSN(ret, node, dup);
+        ADD_INSNL(ret, node, branchnil, lskip);
     }
     ADD_INSN(ret, node, dup);
     ADD_SEND_WITH_FLAG(ret, node, vid, INT2FIX(0), INT2FIX(asgnflag));
 
     if (atype == idOROP || atype == idANDOP) {
-	ADD_INSN(ret, node, dup);
-	if (atype == idOROP) {
-	    ADD_INSNL(ret, node, branchif, lcfin);
-	}
-	else { /* idANDOP */
-	    ADD_INSNL(ret, node, branchunless, lcfin);
-	}
-	ADD_INSN(ret, node, pop);
-	CHECK(COMPILE(ret, "NODE_OP_ASGN2 val", node->nd_value));
-	ADD_INSN(ret, node, swap);
-	ADD_INSN1(ret, node, topn, INT2FIX(1));
-	ADD_SEND_WITH_FLAG(ret, node, aid, INT2FIX(1), INT2FIX(asgnflag));
-	ADD_INSNL(ret, node, jump, lfin);
-
-	ADD_LABEL(ret, lcfin);
-	ADD_INSN(ret, node, swap);
-
-	ADD_LABEL(ret, lfin);
-	ADD_INSN(ret, node, pop);
-	if (lskip) {
-	    ADD_LABEL(ret, lskip);
-	}
-	if (popped) {
-	    /* we can apply more optimize */
-	    ADD_INSN(ret, node, pop);
-	}
+        if (!popped) {
+            ADD_INSN(ret, node, dup);
+        }
+        if (atype == idOROP) {
+            ADD_INSNL(ret, node, branchif, lcfin);
+        }
+        else { /* idANDOP */
+            ADD_INSNL(ret, node, branchunless, lcfin);
+        }
+        if (!popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        CHECK(COMPILE(ret, "NODE_OP_ASGN2 val", node->nd_value));
+        if (!popped) {
+            ADD_INSN(ret, node, swap);
+            ADD_INSN1(ret, node, topn, INT2FIX(1));
+        }
+        ADD_SEND_WITH_FLAG(ret, node, aid, INT2FIX(1), INT2FIX(asgnflag));
+        ADD_INSNL(ret, node, jump, lfin);
+
+        ADD_LABEL(ret, lcfin);
+        if (!popped) {
+            ADD_INSN(ret, node, swap);
+        }
+
+        ADD_LABEL(ret, lfin);
     }
     else {
-	CHECK(COMPILE(ret, "NODE_OP_ASGN2 val", node->nd_value));
-	ADD_SEND(ret, node, atype, INT2FIX(1));
-	if (!popped) {
-	    ADD_INSN(ret, node, swap);
-	    ADD_INSN1(ret, node, topn, INT2FIX(1));
-	}
-	ADD_SEND_WITH_FLAG(ret, node, aid, INT2FIX(1), INT2FIX(asgnflag));
-	if (lskip && popped) {
-	    ADD_LABEL(ret, lskip);
-	}
-	ADD_INSN(ret, node, pop);
-	if (lskip && !popped) {
-	    ADD_LABEL(ret, lskip);
-	}
+        CHECK(COMPILE(ret, "NODE_OP_ASGN2 val", node->nd_value));
+        ADD_SEND(ret, node, atype, INT2FIX(1));
+        if (!popped) {
+            ADD_INSN(ret, node, swap);
+            ADD_INSN1(ret, node, topn, INT2FIX(1));
+        }
+        ADD_SEND_WITH_FLAG(ret, node, aid, INT2FIX(1), INT2FIX(asgnflag));
+    }
+    if (lskip && popped) {
+        ADD_LABEL(ret, lskip);
+    }
+    ADD_INSN(ret, node, pop);
+    if (lskip && !popped) {
+        ADD_LABEL(ret, lskip);
     }
     return COMPILE_OK;
 }
@@ -8508,63 +8826,63 @@ compile_op_cdecl(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node
 
     switch (nd_type(node->nd_head)) {
       case NODE_COLON3:
-	ADD_INSN1(ret, node, putobject, rb_cObject);
-	break;
+        ADD_INSN1(ret, node, putobject, rb_cObject);
+        break;
       case NODE_COLON2:
-	CHECK(COMPILE(ret, "NODE_OP_CDECL/colon2#nd_head", node->nd_head->nd_head));
-	break;
+        CHECK(COMPILE(ret, "NODE_OP_CDECL/colon2#nd_head", node->nd_head->nd_head));
+        break;
       default:
-	COMPILE_ERROR(ERROR_ARGS "%s: invalid node in NODE_OP_CDECL",
-		      ruby_node_name(nd_type(node->nd_head)));
-	return COMPILE_NG;
+        COMPILE_ERROR(ERROR_ARGS "%s: invalid node in NODE_OP_CDECL",
+                      ruby_node_name(nd_type(node->nd_head)));
+        return COMPILE_NG;
     }
     mid = node->nd_head->nd_mid;
     /* cref */
     if (node->nd_aid == idOROP) {
-	lassign = NEW_LABEL(line);
-	ADD_INSN(ret, node, dup); /* cref cref */
-	ADD_INSN3(ret, node, defined, INT2FIX(DEFINED_CONST_FROM),
-		  ID2SYM(mid), Qtrue); /* cref bool */
-	ADD_INSNL(ret, node, branchunless, lassign); /* cref */
+        lassign = NEW_LABEL(line);
+        ADD_INSN(ret, node, dup); /* cref cref */
+        ADD_INSN3(ret, node, defined, INT2FIX(DEFINED_CONST_FROM),
+                  ID2SYM(mid), Qtrue); /* cref bool */
+        ADD_INSNL(ret, node, branchunless, lassign); /* cref */
     }
     ADD_INSN(ret, node, dup); /* cref cref */
     ADD_INSN1(ret, node, putobject, Qtrue);
     ADD_INSN1(ret, node, getconstant, ID2SYM(mid)); /* cref obj */
 
     if (node->nd_aid == idOROP || node->nd_aid == idANDOP) {
-	lfin = NEW_LABEL(line);
-	if (!popped) ADD_INSN(ret, node, dup); /* cref [obj] obj */
-	if (node->nd_aid == idOROP)
-	    ADD_INSNL(ret, node, branchif, lfin);
-	else /* idANDOP */
-	    ADD_INSNL(ret, node, branchunless, lfin);
-	/* cref [obj] */
-	if (!popped) ADD_INSN(ret, node, pop); /* cref */
-	if (lassign) ADD_LABEL(ret, lassign);
-	CHECK(COMPILE(ret, "NODE_OP_CDECL#nd_value", node->nd_value));
-	/* cref value */
-	if (popped)
-	    ADD_INSN1(ret, node, topn, INT2FIX(1)); /* cref value cref */
-	else {
-	    ADD_INSN1(ret, node, dupn, INT2FIX(2)); /* cref value cref value */
-	    ADD_INSN(ret, node, swap); /* cref value value cref */
-	}
-	ADD_INSN1(ret, node, setconstant, ID2SYM(mid)); /* cref [value] */
-	ADD_LABEL(ret, lfin);			    /* cref [value] */
-	if (!popped) ADD_INSN(ret, node, swap); /* [value] cref */
-	ADD_INSN(ret, node, pop); /* [value] */
+        lfin = NEW_LABEL(line);
+        if (!popped) ADD_INSN(ret, node, dup); /* cref [obj] obj */
+        if (node->nd_aid == idOROP)
+            ADD_INSNL(ret, node, branchif, lfin);
+        else /* idANDOP */
+            ADD_INSNL(ret, node, branchunless, lfin);
+        /* cref [obj] */
+        if (!popped) ADD_INSN(ret, node, pop); /* cref */
+        if (lassign) ADD_LABEL(ret, lassign);
+        CHECK(COMPILE(ret, "NODE_OP_CDECL#nd_value", node->nd_value));
+        /* cref value */
+        if (popped)
+            ADD_INSN1(ret, node, topn, INT2FIX(1)); /* cref value cref */
+        else {
+            ADD_INSN1(ret, node, dupn, INT2FIX(2)); /* cref value cref value */
+            ADD_INSN(ret, node, swap); /* cref value value cref */
+        }
+        ADD_INSN1(ret, node, setconstant, ID2SYM(mid)); /* cref [value] */
+        ADD_LABEL(ret, lfin);			    /* cref [value] */
+        if (!popped) ADD_INSN(ret, node, swap); /* [value] cref */
+        ADD_INSN(ret, node, pop); /* [value] */
     }
     else {
-	CHECK(COMPILE(ret, "NODE_OP_CDECL#nd_value", node->nd_value));
-	/* cref obj value */
-	ADD_CALL(ret, node, node->nd_aid, INT2FIX(1));
-	/* cref value */
-	ADD_INSN(ret, node, swap); /* value cref */
-	if (!popped) {
-	    ADD_INSN1(ret, node, topn, INT2FIX(1)); /* value cref value */
-	    ADD_INSN(ret, node, swap); /* value value cref */
-	}
-	ADD_INSN1(ret, node, setconstant, ID2SYM(mid));
+        CHECK(COMPILE(ret, "NODE_OP_CDECL#nd_value", node->nd_value));
+        /* cref obj value */
+        ADD_CALL(ret, node, node->nd_aid, INT2FIX(1));
+        /* cref value */
+        ADD_INSN(ret, node, swap); /* value cref */
+        if (!popped) {
+            ADD_INSN1(ret, node, topn, INT2FIX(1)); /* value cref value */
+            ADD_INSN(ret, node, swap); /* value value cref */
+        }
+        ADD_INSN1(ret, node, setconstant, ID2SYM(mid));
     }
     return COMPILE_OK;
 }
@@ -8577,39 +8895,40 @@ compile_op_log(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node,
     LABEL *lassign;
 
     if (type == NODE_OP_ASGN_OR && !nd_type_p(node->nd_head, NODE_IVAR)) {
-	LABEL *lfinish[2];
-	lfinish[0] = lfin;
-	lfinish[1] = 0;
-	defined_expr(iseq, ret, node->nd_head, lfinish, Qfalse);
-	lassign = lfinish[1];
-	if (!lassign) {
-	    lassign = NEW_LABEL(line);
-	}
-	ADD_INSNL(ret, node, branchunless, lassign);
+        LABEL *lfinish[2];
+        lfinish[0] = lfin;
+        lfinish[1] = 0;
+        defined_expr(iseq, ret, node->nd_head, lfinish, Qfalse);
+        lassign = lfinish[1];
+        if (!lassign) {
+            lassign = NEW_LABEL(line);
+        }
+        ADD_INSNL(ret, node, branchunless, lassign);
     }
     else {
-	lassign = NEW_LABEL(line);
+        lassign = NEW_LABEL(line);
     }
 
     CHECK(COMPILE(ret, "NODE_OP_ASGN_AND/OR#nd_head", node->nd_head));
-    ADD_INSN(ret, node, dup);
+
+    if (!popped) {
+        ADD_INSN(ret, node, dup);
+    }
 
     if (type == NODE_OP_ASGN_AND) {
-	ADD_INSNL(ret, node, branchunless, lfin);
+        ADD_INSNL(ret, node, branchunless, lfin);
     }
     else {
-	ADD_INSNL(ret, node, branchif, lfin);
+        ADD_INSNL(ret, node, branchif, lfin);
+    }
+
+    if (!popped) {
+        ADD_INSN(ret, node, pop);
     }
 
-    ADD_INSN(ret, node, pop);
     ADD_LABEL(ret, lassign);
-    CHECK(COMPILE(ret, "NODE_OP_ASGN_AND/OR#nd_value", node->nd_value));
+    CHECK(COMPILE_(ret, "NODE_OP_ASGN_AND/OR#nd_value", node->nd_value, popped));
     ADD_LABEL(ret, lfin);
-
-    if (popped) {
-	/* we can apply more optimize */
-	ADD_INSN(ret, node, pop);
-    }
     return COMPILE_OK;
 }
 
@@ -8626,115 +8945,115 @@ compile_super(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, i
     INIT_ANCHOR(args);
     ISEQ_COMPILE_DATA(iseq)->current_block = NULL;
     if (type == NODE_SUPER) {
-	VALUE vargc = setup_args(iseq, args, node->nd_args, &flag, &keywords);
-	CHECK(!NIL_P(vargc));
-	argc = FIX2INT(vargc);
+        VALUE vargc = setup_args(iseq, args, node->nd_args, &flag, &keywords);
+        CHECK(!NIL_P(vargc));
+        argc = FIX2INT(vargc);
     }
     else {
-	/* NODE_ZSUPER */
-	int i;
-	const rb_iseq_t *liseq = body->local_iseq;
+        /* NODE_ZSUPER */
+        int i;
+        const rb_iseq_t *liseq = body->local_iseq;
         const struct rb_iseq_constant_body *const local_body = ISEQ_BODY(liseq);
-	const struct rb_iseq_param_keyword *const local_kwd = local_body->param.keyword;
-	int lvar_level = get_lvar_level(iseq);
-
-	argc = local_body->param.lead_num;
-
-	/* normal arguments */
-	for (i = 0; i < local_body->param.lead_num; i++) {
-	    int idx = local_body->local_table_size - i;
-	    ADD_GETLOCAL(args, node, idx, lvar_level);
-	}
-
-	if (local_body->param.flags.has_opt) {
-	    /* optional arguments */
-	    int j;
-	    for (j = 0; j < local_body->param.opt_num; j++) {
-		int idx = local_body->local_table_size - (i + j);
-		ADD_GETLOCAL(args, node, idx, lvar_level);
-	    }
-	    i += j;
-	    argc = i;
-	}
-	if (local_body->param.flags.has_rest) {
-	    /* rest argument */
-	    int idx = local_body->local_table_size - local_body->param.rest_start;
-	    ADD_GETLOCAL(args, node, idx, lvar_level);
-	    ADD_INSN1(args, node, splatarray, Qfalse);
-
-	    argc = local_body->param.rest_start + 1;
-	    flag |= VM_CALL_ARGS_SPLAT;
-	}
-	if (local_body->param.flags.has_post) {
-	    /* post arguments */
-	    int post_len = local_body->param.post_num;
-	    int post_start = local_body->param.post_start;
-
-	    if (local_body->param.flags.has_rest) {
-		int j;
-		for (j=0; j<post_len; j++) {
-		    int idx = local_body->local_table_size - (post_start + j);
-		    ADD_GETLOCAL(args, node, idx, lvar_level);
-		}
-		ADD_INSN1(args, node, newarray, INT2FIX(j));
-		ADD_INSN (args, node, concatarray);
-		/* argc is settled at above */
-	    }
-	    else {
-		int j;
-		for (j=0; j<post_len; j++) {
-		    int idx = local_body->local_table_size - (post_start + j);
-		    ADD_GETLOCAL(args, node, idx, lvar_level);
-		}
-		argc = post_len + post_start;
-	    }
-	}
-
-	if (local_body->param.flags.has_kw) { /* TODO: support keywords */
-	    int local_size = local_body->local_table_size;
-	    argc++;
-
-	    ADD_INSN1(args, node, putspecialobject, INT2FIX(VM_SPECIAL_OBJECT_VMCORE));
-
-	    if (local_body->param.flags.has_kwrest) {
-		int idx = local_body->local_table_size - local_kwd->rest_start;
-		ADD_GETLOCAL(args, node, idx, lvar_level);
+        const struct rb_iseq_param_keyword *const local_kwd = local_body->param.keyword;
+        int lvar_level = get_lvar_level(iseq);
+
+        argc = local_body->param.lead_num;
+
+        /* normal arguments */
+        for (i = 0; i < local_body->param.lead_num; i++) {
+            int idx = local_body->local_table_size - i;
+            ADD_GETLOCAL(args, node, idx, lvar_level);
+        }
+
+        if (local_body->param.flags.has_opt) {
+            /* optional arguments */
+            int j;
+            for (j = 0; j < local_body->param.opt_num; j++) {
+                int idx = local_body->local_table_size - (i + j);
+                ADD_GETLOCAL(args, node, idx, lvar_level);
+            }
+            i += j;
+            argc = i;
+        }
+        if (local_body->param.flags.has_rest) {
+            /* rest argument */
+            int idx = local_body->local_table_size - local_body->param.rest_start;
+            ADD_GETLOCAL(args, node, idx, lvar_level);
+            ADD_INSN1(args, node, splatarray, Qfalse);
+
+            argc = local_body->param.rest_start + 1;
+            flag |= VM_CALL_ARGS_SPLAT;
+        }
+        if (local_body->param.flags.has_post) {
+            /* post arguments */
+            int post_len = local_body->param.post_num;
+            int post_start = local_body->param.post_start;
+
+            if (local_body->param.flags.has_rest) {
+                int j;
+                for (j=0; j<post_len; j++) {
+                    int idx = local_body->local_table_size - (post_start + j);
+                    ADD_GETLOCAL(args, node, idx, lvar_level);
+                }
+                ADD_INSN1(args, node, newarray, INT2FIX(j));
+                ADD_INSN (args, node, concatarray);
+                /* argc is settled at above */
+            }
+            else {
+                int j;
+                for (j=0; j<post_len; j++) {
+                    int idx = local_body->local_table_size - (post_start + j);
+                    ADD_GETLOCAL(args, node, idx, lvar_level);
+                }
+                argc = post_len + post_start;
+            }
+        }
+
+        if (local_body->param.flags.has_kw) { /* TODO: support keywords */
+            int local_size = local_body->local_table_size;
+            argc++;
+
+            ADD_INSN1(args, node, putspecialobject, INT2FIX(VM_SPECIAL_OBJECT_VMCORE));
+
+            if (local_body->param.flags.has_kwrest) {
+                int idx = local_body->local_table_size - local_kwd->rest_start;
+                ADD_GETLOCAL(args, node, idx, lvar_level);
                 if (local_kwd->num > 0) {
                     ADD_SEND (args, node, rb_intern("dup"), INT2FIX(0));
                     flag |= VM_CALL_KW_SPLAT_MUT;
                 }
-	    }
-	    else {
-		ADD_INSN1(args, node, newhash, INT2FIX(0));
+            }
+            else {
+                ADD_INSN1(args, node, newhash, INT2FIX(0));
                 flag |= VM_CALL_KW_SPLAT_MUT;
-	    }
-	    for (i = 0; i < local_kwd->num; ++i) {
-		ID id = local_kwd->table[i];
-		int idx = local_size - get_local_var_idx(liseq, id);
-		ADD_INSN1(args, node, putobject, ID2SYM(id));
-		ADD_GETLOCAL(args, node, idx, lvar_level);
-	    }
-	    ADD_SEND(args, node, id_core_hash_merge_ptr, INT2FIX(i * 2 + 1));
-	    if (local_body->param.flags.has_rest) {
-		ADD_INSN1(args, node, newarray, INT2FIX(1));
-		ADD_INSN (args, node, concatarray);
-		--argc;
-	    }
+            }
+            for (i = 0; i < local_kwd->num; ++i) {
+                ID id = local_kwd->table[i];
+                int idx = local_size - get_local_var_idx(liseq, id);
+                ADD_INSN1(args, node, putobject, ID2SYM(id));
+                ADD_GETLOCAL(args, node, idx, lvar_level);
+            }
+            ADD_SEND(args, node, id_core_hash_merge_ptr, INT2FIX(i * 2 + 1));
+            if (local_body->param.flags.has_rest) {
+                ADD_INSN1(args, node, newarray, INT2FIX(1));
+                ADD_INSN (args, node, concatarray);
+                --argc;
+            }
             flag |= VM_CALL_KW_SPLAT;
-	}
-	else if (local_body->param.flags.has_kwrest) {
-	    int idx = local_body->local_table_size - local_kwd->rest_start;
-	    ADD_GETLOCAL(args, node, idx, lvar_level);
-
-	    if (local_body->param.flags.has_rest) {
-		ADD_INSN1(args, node, newarray, INT2FIX(1));
-		ADD_INSN (args, node, concatarray);
-	    }
-	    else {
-		argc++;
-	    }
+        }
+        else if (local_body->param.flags.has_kwrest) {
+            int idx = local_body->local_table_size - local_kwd->rest_start;
+            ADD_GETLOCAL(args, node, idx, lvar_level);
+
+            if (local_body->param.flags.has_rest) {
+                ADD_INSN1(args, node, newarray, INT2FIX(1));
+                ADD_INSN (args, node, concatarray);
+            }
+            else {
+                argc++;
+            }
             flag |= VM_CALL_KW_SPLAT;
-	}
+        }
     }
 
     flag |= VM_CALL_SUPER | VM_CALL_FCALL;
@@ -8742,11 +9061,11 @@ compile_super(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, i
     ADD_INSN(ret, node, putself);
     ADD_SEQ(ret, args);
     ADD_INSN2(ret, node, invokesuper,
-	      new_callinfo(iseq, 0, argc, flag, keywords, parent_block != NULL),
-	      parent_block);
+              new_callinfo(iseq, 0, argc, flag, keywords, parent_block != NULL),
+              parent_block);
 
     if (popped) {
-	ADD_INSN(ret, node, pop);
+        ADD_INSN(ret, node, pop);
     }
     return COMPILE_OK;
 }
@@ -8765,24 +9084,24 @@ compile_yield(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, i
       case ISEQ_TYPE_TOP:
       case ISEQ_TYPE_MAIN:
       case ISEQ_TYPE_CLASS:
-	COMPILE_ERROR(ERROR_ARGS "Invalid yield");
-	return COMPILE_NG;
+        COMPILE_ERROR(ERROR_ARGS "Invalid yield");
+        return COMPILE_NG;
       default: /* valid */;
     }
 
     if (node->nd_head) {
-	argc = setup_args(iseq, args, node->nd_head, &flag, &keywords);
-	CHECK(!NIL_P(argc));
+        argc = setup_args(iseq, args, node->nd_head, &flag, &keywords);
+        CHECK(!NIL_P(argc));
     }
     else {
-	argc = INT2FIX(0);
+        argc = INT2FIX(0);
     }
 
     ADD_SEQ(ret, args);
     ADD_INSN1(ret, node, invokeblock, new_callinfo(iseq, 0, FIX2INT(argc), flag, keywords, FALSE));
 
     if (popped) {
-	ADD_INSN(ret, node, pop);
+        ADD_INSN(ret, node, pop);
     }
 
     int level = 0;
@@ -8805,18 +9124,18 @@ compile_match(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, i
     INIT_ANCHOR(val);
     switch ((int)type) {
       case NODE_MATCH:
-	ADD_INSN1(recv, node, putobject, node->nd_lit);
-	ADD_INSN2(val, node, getspecial, INT2FIX(0),
-		  INT2FIX(0));
-	break;
+        ADD_INSN1(recv, node, putobject, node->nd_lit);
+        ADD_INSN2(val, node, getspecial, INT2FIX(0),
+                  INT2FIX(0));
+        break;
       case NODE_MATCH2:
-	CHECK(COMPILE(recv, "receiver", node->nd_recv));
-	CHECK(COMPILE(val, "value", node->nd_value));
-	break;
+        CHECK(COMPILE(recv, "receiver", node->nd_recv));
+        CHECK(COMPILE(val, "value", node->nd_value));
+        break;
       case NODE_MATCH3:
-	CHECK(COMPILE(recv, "receiver", node->nd_value));
-	CHECK(COMPILE(val, "value", node->nd_recv));
-	break;
+        CHECK(COMPILE(recv, "receiver", node->nd_value));
+        CHECK(COMPILE(val, "value", node->nd_recv));
+        break;
     }
 
     ADD_SEQ(ret, recv);
@@ -8824,11 +9143,11 @@ compile_match(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, i
     ADD_SEND(ret, node, idEqTilde, INT2FIX(1));
 
     if (node->nd_args) {
-	compile_named_capture_assign(iseq, ret, node->nd_args);
+        compile_named_capture_assign(iseq, ret, node->nd_args);
     }
 
     if (popped) {
-	ADD_INSN(ret, node, pop);
+        ADD_INSN(ret, node, pop);
     }
     return COMPILE_OK;
 }
@@ -8836,46 +9155,41 @@ compile_match(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, i
 static int
 compile_colon2(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, int popped)
 {
-    const int line = nd_line(node);
     if (rb_is_const_id(node->nd_mid)) {
-	/* constant */
-	LABEL *lend = NEW_LABEL(line);
-        int ic_index = ISEQ_BODY(iseq)->is_size++;
-
-	DECL_ANCHOR(pref);
-	DECL_ANCHOR(body);
-
-	INIT_ANCHOR(pref);
-	INIT_ANCHOR(body);
-	CHECK(compile_const_prefix(iseq, node, pref, body));
-	if (LIST_INSN_SIZE_ZERO(pref)) {
-	    if (ISEQ_COMPILE_DATA(iseq)->option->inline_const_cache) {
-		ADD_INSN2(ret, node, opt_getinlinecache, lend, INT2FIX(ic_index));
-	    }
-	    else {
-		ADD_INSN(ret, node, putnil);
-	    }
-
-	    ADD_SEQ(ret, body);
-
-	    if (ISEQ_COMPILE_DATA(iseq)->option->inline_const_cache) {
-		ADD_INSN1(ret, node, opt_setinlinecache, INT2FIX(ic_index));
-		ADD_LABEL(ret, lend);
-	    }
-	}
-	else {
-	    ADD_SEQ(ret, pref);
-	    ADD_SEQ(ret, body);
-	}
+        /* constant */
+        VALUE segments;
+        if (ISEQ_COMPILE_DATA(iseq)->option->inline_const_cache &&
+                (segments = collect_const_segments(iseq, node))) {
+            ISEQ_BODY(iseq)->ic_size++;
+            ADD_INSN1(ret, node, opt_getconstant_path, segments);
+            RB_OBJ_WRITTEN(iseq, Qundef, segments);
+        }
+        else {
+            /* constant */
+            DECL_ANCHOR(pref);
+            DECL_ANCHOR(body);
+
+            INIT_ANCHOR(pref);
+            INIT_ANCHOR(body);
+            CHECK(compile_const_prefix(iseq, node, pref, body));
+            if (LIST_INSN_SIZE_ZERO(pref)) {
+                ADD_INSN(ret, node, putnil);
+                ADD_SEQ(ret, body);
+            }
+            else {
+                ADD_SEQ(ret, pref);
+                ADD_SEQ(ret, body);
+            }
+        }
     }
     else {
-	/* function call */
-	ADD_CALL_RECEIVER(ret, node);
-	CHECK(COMPILE(ret, "colon2#nd_head", node->nd_head));
-	ADD_CALL(ret, node, node->nd_mid, INT2FIX(1));
+        /* function call */
+        ADD_CALL_RECEIVER(ret, node);
+        CHECK(COMPILE(ret, "colon2#nd_head", node->nd_head));
+        ADD_CALL(ret, node, node->nd_mid, INT2FIX(1));
     }
     if (popped) {
-	ADD_INSN(ret, node, pop);
+        ADD_INSN(ret, node, pop);
     }
     return COMPILE_OK;
 }
@@ -8883,29 +9197,23 @@ compile_colon2(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node,
 static int
 compile_colon3(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, int popped)
 {
-    const int line = nd_line(node);
-    LABEL *lend = NEW_LABEL(line);
-    int ic_index = ISEQ_BODY(iseq)->is_size++;
-
     debugi("colon3#nd_mid", node->nd_mid);
 
     /* add cache insn */
     if (ISEQ_COMPILE_DATA(iseq)->option->inline_const_cache) {
-	ADD_INSN2(ret, node, opt_getinlinecache, lend, INT2FIX(ic_index));
-	ADD_INSN(ret, node, pop);
+        ISEQ_BODY(iseq)->ic_size++;
+        VALUE segments = rb_ary_new_from_args(2, ID2SYM(idNULL), ID2SYM(node->nd_mid));
+        ADD_INSN1(ret, node, opt_getconstant_path, segments);
+        RB_OBJ_WRITTEN(iseq, Qundef, segments);
     }
-
-    ADD_INSN1(ret, node, putobject, rb_cObject);
-    ADD_INSN1(ret, node, putobject, Qtrue);
-    ADD_INSN1(ret, node, getconstant, ID2SYM(node->nd_mid));
-
-    if (ISEQ_COMPILE_DATA(iseq)->option->inline_const_cache) {
-	ADD_INSN1(ret, node, opt_setinlinecache, INT2FIX(ic_index));
-	ADD_LABEL(ret, lend);
+    else {
+        ADD_INSN1(ret, node, putobject, rb_cObject);
+        ADD_INSN1(ret, node, putobject, Qtrue);
+        ADD_INSN1(ret, node, getconstant, ID2SYM(node->nd_mid));
     }
 
     if (popped) {
-	ADD_INSN(ret, node, pop);
+        ADD_INSN(ret, node, pop);
     }
     return COMPILE_OK;
 }
@@ -8918,20 +9226,20 @@ compile_dots(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, in
     const NODE *e = node->nd_end;
 
     if (optimizable_range_item_p(b) && optimizable_range_item_p(e)) {
-	if (!popped) {
+        if (!popped) {
             VALUE bv = nd_type_p(b, NODE_LIT) ? b->nd_lit : Qnil;
             VALUE ev = nd_type_p(e, NODE_LIT) ? e->nd_lit : Qnil;
-	    VALUE val = rb_range_new(bv, ev, excl);
-	    ADD_INSN1(ret, node, putobject, val);
-	    RB_OBJ_WRITTEN(iseq, Qundef, val);
-	}
+            VALUE val = rb_range_new(bv, ev, excl);
+            ADD_INSN1(ret, node, putobject, val);
+            RB_OBJ_WRITTEN(iseq, Qundef, val);
+        }
     }
     else {
-	CHECK(COMPILE_(ret, "min", b, popped));
-	CHECK(COMPILE_(ret, "max", e, popped));
-	if (!popped) {
-	    ADD_INSN1(ret, node, newrange, flag);
-	}
+        CHECK(COMPILE_(ret, "min", b, popped));
+        CHECK(COMPILE_(ret, "max", e, popped));
+        if (!popped) {
+            ADD_INSN1(ret, node, newrange, flag);
+        }
     }
     return COMPILE_OK;
 }
@@ -8941,25 +9249,25 @@ compile_errinfo(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node,
 {
     if (!popped) {
         if (ISEQ_BODY(iseq)->type == ISEQ_TYPE_RESCUE) {
-	    ADD_GETLOCAL(ret, node, LVAR_ERRINFO, 0);
-	}
-	else {
-	    const rb_iseq_t *ip = iseq;
-	    int level = 0;
-	    while (ip) {
+            ADD_GETLOCAL(ret, node, LVAR_ERRINFO, 0);
+        }
+        else {
+            const rb_iseq_t *ip = iseq;
+            int level = 0;
+            while (ip) {
                 if (ISEQ_BODY(ip)->type == ISEQ_TYPE_RESCUE) {
-		    break;
-		}
+                    break;
+                }
                 ip = ISEQ_BODY(ip)->parent_iseq;
-		level++;
-	    }
-	    if (ip) {
-		ADD_GETLOCAL(ret, node, LVAR_ERRINFO, level);
-	    }
-	    else {
-		ADD_INSN(ret, node, putnil);
-	    }
-	}
+                level++;
+            }
+            if (ip) {
+                ADD_GETLOCAL(ret, node, LVAR_ERRINFO, level);
+            }
+            else {
+                ADD_INSN(ret, node, putnil);
+            }
+        }
     }
     return COMPILE_OK;
 }
@@ -8972,29 +9280,29 @@ compile_kw_arg(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node,
     const NODE *default_value = node->nd_body->nd_value;
 
     if (default_value == NODE_SPECIAL_REQUIRED_KEYWORD) {
-	/* required argument. do nothing */
-	COMPILE_ERROR(ERROR_ARGS "unreachable");
-	return COMPILE_NG;
+        /* required argument. do nothing */
+        COMPILE_ERROR(ERROR_ARGS "unreachable");
+        return COMPILE_NG;
     }
     else if (nd_type_p(default_value, NODE_LIT) ||
-	     nd_type_p(default_value, NODE_NIL) ||
-	     nd_type_p(default_value, NODE_TRUE) ||
-	     nd_type_p(default_value, NODE_FALSE)) {
-	COMPILE_ERROR(ERROR_ARGS "unreachable");
-	return COMPILE_NG;
+             nd_type_p(default_value, NODE_NIL) ||
+             nd_type_p(default_value, NODE_TRUE) ||
+             nd_type_p(default_value, NODE_FALSE)) {
+        COMPILE_ERROR(ERROR_ARGS "unreachable");
+        return COMPILE_NG;
     }
     else {
-	/* if keywordcheck(_kw_bits, nth_keyword)
-	 *   kw = default_value
-	 * end
-	 */
-	int kw_bits_idx = body->local_table_size - body->param.keyword->bits_start;
-	int keyword_idx = body->param.keyword->num;
-
-	ADD_INSN2(ret, node, checkkeyword, INT2FIX(kw_bits_idx + VM_ENV_DATA_SIZE - 1), INT2FIX(keyword_idx));
-	ADD_INSNL(ret, node, branchif, end_label);
-	CHECK(COMPILE_POPPED(ret, "keyword default argument", node->nd_body));
-	ADD_LABEL(ret, end_label);
+        /* if keywordcheck(_kw_bits, nth_keyword)
+         *   kw = default_value
+         * end
+         */
+        int kw_bits_idx = body->local_table_size - body->param.keyword->bits_start;
+        int keyword_idx = body->param.keyword->num;
+
+        ADD_INSN2(ret, node, checkkeyword, INT2FIX(kw_bits_idx + VM_ENV_DATA_SIZE - 1), INT2FIX(keyword_idx));
+        ADD_INSNL(ret, node, branchif, end_label);
+        CHECK(COMPILE_POPPED(ret, "keyword default argument", node->nd_body));
+        ADD_LABEL(ret, end_label);
     }
     return COMPILE_OK;
 }
@@ -9013,25 +9321,26 @@ compile_attrasgn(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node
     /* optimization shortcut
      *   obj["literal"] = value -> opt_aset_with(obj, "literal", value)
      */
-    if (mid == idASET && !private_recv_p(node) && node->nd_args &&
-	nd_type_p(node->nd_args, NODE_LIST) && node->nd_args->nd_alen == 2 &&
-	nd_type_p(node->nd_args->nd_head, NODE_STR) &&
-	ISEQ_COMPILE_DATA(iseq)->current_block == NULL &&
-	!ISEQ_COMPILE_DATA(iseq)->option->frozen_string_literal &&
-	ISEQ_COMPILE_DATA(iseq)->option->specialized_instruction)
+    if (!ISEQ_COMPILE_DATA(iseq)->in_masgn &&
+        mid == idASET && !private_recv_p(node) && node->nd_args &&
+        nd_type_p(node->nd_args, NODE_LIST) && node->nd_args->nd_alen == 2 &&
+        nd_type_p(node->nd_args->nd_head, NODE_STR) &&
+        ISEQ_COMPILE_DATA(iseq)->current_block == NULL &&
+        !ISEQ_COMPILE_DATA(iseq)->option->frozen_string_literal &&
+        ISEQ_COMPILE_DATA(iseq)->option->specialized_instruction)
     {
-	VALUE str = rb_fstring(node->nd_args->nd_head->nd_lit);
-	CHECK(COMPILE(ret, "recv", node->nd_recv));
-	CHECK(COMPILE(ret, "value", node->nd_args->nd_next->nd_head));
-	if (!popped) {
-	    ADD_INSN(ret, node, swap);
-	    ADD_INSN1(ret, node, topn, INT2FIX(1));
-	}
-	ADD_INSN2(ret, node, opt_aset_with, str,
-		  new_callinfo(iseq, idASET, 2, 0, NULL, FALSE));
-	RB_OBJ_WRITTEN(iseq, Qundef, str);
-	ADD_INSN(ret, node, pop);
-	return COMPILE_OK;
+        VALUE str = rb_fstring(node->nd_args->nd_head->nd_lit);
+        CHECK(COMPILE(ret, "recv", node->nd_recv));
+        CHECK(COMPILE(ret, "value", node->nd_args->nd_next->nd_head));
+        if (!popped) {
+            ADD_INSN(ret, node, swap);
+            ADD_INSN1(ret, node, topn, INT2FIX(1));
+        }
+        ADD_INSN2(ret, node, opt_aset_with, str,
+                  new_callinfo(iseq, idASET, 2, 0, NULL, FALSE));
+        RB_OBJ_WRITTEN(iseq, Qundef, str);
+        ADD_INSN(ret, node, pop);
+        return COMPILE_OK;
     }
 
     INIT_ANCHOR(recv);
@@ -9047,38 +9356,38 @@ compile_attrasgn(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node
     debugp_param("nd_mid", ID2SYM(mid));
 
     if (!rb_is_attrset_id(mid)) {
-	/* safe nav attr */
-	mid = rb_id_attrset(mid);
-	else_label = qcall_branch_start(iseq, recv, &branches, node, node);
+        /* safe nav attr */
+        mid = rb_id_attrset(mid);
+        else_label = qcall_branch_start(iseq, recv, &branches, node, node);
     }
     if (!popped) {
-	ADD_INSN(ret, node, putnil);
-	ADD_SEQ(ret, recv);
-	ADD_SEQ(ret, args);
-
-	if (flag & VM_CALL_ARGS_BLOCKARG) {
-	    ADD_INSN1(ret, node, topn, INT2FIX(1));
-	    if (flag & VM_CALL_ARGS_SPLAT) {
-		ADD_INSN1(ret, node, putobject, INT2FIX(-1));
-		ADD_SEND_WITH_FLAG(ret, node, idAREF, INT2FIX(1), INT2FIX(asgnflag));
-	    }
-	    ADD_INSN1(ret, node, setn, FIXNUM_INC(argc, 3));
-	    ADD_INSN (ret, node, pop);
-	}
-	else if (flag & VM_CALL_ARGS_SPLAT) {
-	    ADD_INSN(ret, node, dup);
-	    ADD_INSN1(ret, node, putobject, INT2FIX(-1));
-	    ADD_SEND_WITH_FLAG(ret, node, idAREF, INT2FIX(1), INT2FIX(asgnflag));
-	    ADD_INSN1(ret, node, setn, FIXNUM_INC(argc, 2));
-	    ADD_INSN (ret, node, pop);
-	}
-	else {
-	    ADD_INSN1(ret, node, setn, FIXNUM_INC(argc, 1));
-	}
+        ADD_INSN(ret, node, putnil);
+        ADD_SEQ(ret, recv);
+        ADD_SEQ(ret, args);
+
+        if (flag & VM_CALL_ARGS_BLOCKARG) {
+            ADD_INSN1(ret, node, topn, INT2FIX(1));
+            if (flag & VM_CALL_ARGS_SPLAT) {
+                ADD_INSN1(ret, node, putobject, INT2FIX(-1));
+                ADD_SEND_WITH_FLAG(ret, node, idAREF, INT2FIX(1), INT2FIX(asgnflag));
+            }
+            ADD_INSN1(ret, node, setn, FIXNUM_INC(argc, 3));
+            ADD_INSN (ret, node, pop);
+        }
+        else if (flag & VM_CALL_ARGS_SPLAT) {
+            ADD_INSN(ret, node, dup);
+            ADD_INSN1(ret, node, putobject, INT2FIX(-1));
+            ADD_SEND_WITH_FLAG(ret, node, idAREF, INT2FIX(1), INT2FIX(asgnflag));
+            ADD_INSN1(ret, node, setn, FIXNUM_INC(argc, 2));
+            ADD_INSN (ret, node, pop);
+        }
+        else {
+            ADD_INSN1(ret, node, setn, FIXNUM_INC(argc, 1));
+        }
     }
     else {
-	ADD_SEQ(ret, recv);
-	ADD_SEQ(ret, args);
+        ADD_SEQ(ret, recv);
+        ADD_SEQ(ret, args);
     }
     ADD_SEND_WITH_FLAG(ret, node, mid, argc, INT2FIX(flag));
     qcall_branch_end(iseq, ret, else_label, branches, node, node);
@@ -9118,17 +9427,17 @@ iseq_compile_each0(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const no
     struct rb_iseq_constant_body *const body = ISEQ_BODY(iseq);
 
     if (ISEQ_COMPILE_DATA(iseq)->last_line == line) {
-	/* ignore */
+        /* ignore */
     }
     else {
-	if (node->flags & NODE_FL_NEWLINE) {
-	    int event = RUBY_EVENT_LINE;
-	    ISEQ_COMPILE_DATA(iseq)->last_line = line;
-	    if (ISEQ_COVERAGE(iseq) && ISEQ_LINE_COVERAGE(iseq)) {
-		event |= RUBY_EVENT_COVERAGE_LINE;
-	    }
-	    ADD_TRACE(ret, event);
-	}
+        if (node->flags & NODE_FL_NEWLINE) {
+            int event = RUBY_EVENT_LINE;
+            ISEQ_COMPILE_DATA(iseq)->last_line = line;
+            if (ISEQ_COVERAGE(iseq) && ISEQ_LINE_COVERAGE(iseq)) {
+                event |= RUBY_EVENT_COVERAGE_LINE;
+            }
+            ADD_TRACE(ret, event);
+        }
     }
 
     debug_node_start(node);
@@ -9138,134 +9447,137 @@ iseq_compile_each0(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const no
     switch (type) {
       case NODE_BLOCK:
         CHECK(compile_block(iseq, ret, node, popped));
-	break;
+        break;
       case NODE_IF:
       case NODE_UNLESS:
-	CHECK(compile_if(iseq, ret, node, popped, type));
-	break;
+        CHECK(compile_if(iseq, ret, node, popped, type));
+        break;
       case NODE_CASE:
-	CHECK(compile_case(iseq, ret, node, popped));
-	break;
+        CHECK(compile_case(iseq, ret, node, popped));
+        break;
       case NODE_CASE2:
-	CHECK(compile_case2(iseq, ret, node, popped));
-	break;
+        CHECK(compile_case2(iseq, ret, node, popped));
+        break;
       case NODE_CASE3:
         CHECK(compile_case3(iseq, ret, node, popped));
         break;
       case NODE_WHILE:
       case NODE_UNTIL:
-	CHECK(compile_loop(iseq, ret, node, popped, type));
-	break;
+        CHECK(compile_loop(iseq, ret, node, popped, type));
+        break;
       case NODE_FOR:
       case NODE_ITER:
-	CHECK(compile_iter(iseq, ret, node, popped));
-	break;
+        CHECK(compile_iter(iseq, ret, node, popped));
+        break;
       case NODE_FOR_MASGN:
-	CHECK(compile_for_masgn(iseq, ret, node, popped));
-	break;
+        CHECK(compile_for_masgn(iseq, ret, node, popped));
+        break;
       case NODE_BREAK:
-	CHECK(compile_break(iseq, ret, node, popped));
-	break;
+        CHECK(compile_break(iseq, ret, node, popped));
+        break;
       case NODE_NEXT:
-	CHECK(compile_next(iseq, ret, node, popped));
-	break;
+        CHECK(compile_next(iseq, ret, node, popped));
+        break;
       case NODE_REDO:
-	CHECK(compile_redo(iseq, ret, node, popped));
-	break;
+        CHECK(compile_redo(iseq, ret, node, popped));
+        break;
       case NODE_RETRY:
-	CHECK(compile_retry(iseq, ret, node, popped));
-	break;
+        CHECK(compile_retry(iseq, ret, node, popped));
+        break;
       case NODE_BEGIN:{
-	CHECK(COMPILE_(ret, "NODE_BEGIN", node->nd_body, popped));
-	break;
+        CHECK(COMPILE_(ret, "NODE_BEGIN", node->nd_body, popped));
+        break;
       }
       case NODE_RESCUE:
-	CHECK(compile_rescue(iseq, ret, node, popped));
-	break;
+        CHECK(compile_rescue(iseq, ret, node, popped));
+        break;
       case NODE_RESBODY:
-	CHECK(compile_resbody(iseq, ret, node, popped));
-	break;
+        CHECK(compile_resbody(iseq, ret, node, popped));
+        break;
       case NODE_ENSURE:
-	CHECK(compile_ensure(iseq, ret, node, popped));
-	break;
+        CHECK(compile_ensure(iseq, ret, node, popped));
+        break;
 
       case NODE_AND:
       case NODE_OR:{
-	LABEL *end_label = NEW_LABEL(line);
-	CHECK(COMPILE(ret, "nd_1st", node->nd_1st));
-	if (!popped) {
-	    ADD_INSN(ret, node, dup);
-	}
-	if (type == NODE_AND) {
-	    ADD_INSNL(ret, node, branchunless, end_label);
-	}
-	else {
-	    ADD_INSNL(ret, node, branchif, end_label);
-	}
-	if (!popped) {
-	    ADD_INSN(ret, node, pop);
-	}
-	CHECK(COMPILE_(ret, "nd_2nd", node->nd_2nd, popped));
-	ADD_LABEL(ret, end_label);
-	break;
+        LABEL *end_label = NEW_LABEL(line);
+        CHECK(COMPILE(ret, "nd_1st", node->nd_1st));
+        if (!popped) {
+            ADD_INSN(ret, node, dup);
+        }
+        if (type == NODE_AND) {
+            ADD_INSNL(ret, node, branchunless, end_label);
+        }
+        else {
+            ADD_INSNL(ret, node, branchif, end_label);
+        }
+        if (!popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        CHECK(COMPILE_(ret, "nd_2nd", node->nd_2nd, popped));
+        ADD_LABEL(ret, end_label);
+        break;
       }
 
       case NODE_MASGN:{
-	compile_massign(iseq, ret, node, popped);
-	break;
+        bool prev_in_masgn = ISEQ_COMPILE_DATA(iseq)->in_masgn;
+        ISEQ_COMPILE_DATA(iseq)->in_masgn = true;
+        compile_massign(iseq, ret, node, popped);
+        ISEQ_COMPILE_DATA(iseq)->in_masgn = prev_in_masgn;
+        break;
       }
 
       case NODE_LASGN:{
-	ID id = node->nd_vid;
+        ID id = node->nd_vid;
         int idx = ISEQ_BODY(body->local_iseq)->local_table_size - get_local_var_idx(iseq, id);
 
-	debugs("lvar: %s idx: %d\n", rb_id2name(id), idx);
-	CHECK(COMPILE(ret, "rvalue", node->nd_value));
+        debugs("lvar: %s idx: %d\n", rb_id2name(id), idx);
+        CHECK(COMPILE(ret, "rvalue", node->nd_value));
 
-	if (!popped) {
-	    ADD_INSN(ret, node, dup);
-	}
-	ADD_SETLOCAL(ret, node, idx, get_lvar_level(iseq));
-	break;
+        if (!popped) {
+            ADD_INSN(ret, node, dup);
+        }
+        ADD_SETLOCAL(ret, node, idx, get_lvar_level(iseq));
+        break;
       }
       case NODE_DASGN: {
-	int idx, lv, ls;
-	ID id = node->nd_vid;
-	CHECK(COMPILE(ret, "dvalue", node->nd_value));
-	debugi("dassn id", rb_id2str(id) ? id : '*');
-
-	if (!popped) {
-	    ADD_INSN(ret, node, dup);
-	}
-
-	idx = get_dyna_var_idx(iseq, id, &lv, &ls);
-
-	if (idx < 0) {
-	    COMPILE_ERROR(ERROR_ARGS "NODE_DASGN: unknown id (%"PRIsVALUE")",
-			  rb_id2str(id));
-	    goto ng;
-	}
-	ADD_SETLOCAL(ret, node, ls - idx, lv);
-	break;
+        int idx, lv, ls;
+        ID id = node->nd_vid;
+        CHECK(COMPILE(ret, "dvalue", node->nd_value));
+        debugi("dassn id", rb_id2str(id) ? id : '*');
+
+        if (!popped) {
+            ADD_INSN(ret, node, dup);
+        }
+
+        idx = get_dyna_var_idx(iseq, id, &lv, &ls);
+
+        if (idx < 0) {
+            COMPILE_ERROR(ERROR_ARGS "NODE_DASGN: unknown id (%"PRIsVALUE")",
+                          rb_id2str(id));
+            goto ng;
+        }
+        ADD_SETLOCAL(ret, node, ls - idx, lv);
+        break;
       }
       case NODE_GASGN:{
-	CHECK(COMPILE(ret, "lvalue", node->nd_value));
+        CHECK(COMPILE(ret, "lvalue", node->nd_value));
 
-	if (!popped) {
-	    ADD_INSN(ret, node, dup);
-	}
-	ADD_INSN1(ret, node, setglobal, ID2SYM(node->nd_entry));
-	break;
+        if (!popped) {
+            ADD_INSN(ret, node, dup);
+        }
+        ADD_INSN1(ret, node, setglobal, ID2SYM(node->nd_entry));
+        break;
       }
       case NODE_IASGN:{
-	CHECK(COMPILE(ret, "lvalue", node->nd_value));
-	if (!popped) {
-	    ADD_INSN(ret, node, dup);
-	}
-	ADD_INSN2(ret, node, setinstancevariable,
-		  ID2SYM(node->nd_vid),
-		  get_ivar_ic_value(iseq,node->nd_vid));
-	break;
+        CHECK(COMPILE(ret, "lvalue", node->nd_value));
+        if (!popped) {
+            ADD_INSN(ret, node, dup);
+        }
+        ADD_INSN2(ret, node, setinstancevariable,
+                  ID2SYM(node->nd_vid),
+                  get_ivar_ic_value(iseq,node->nd_vid));
+        break;
       }
       case NODE_CDECL:{
         if (node->nd_vid) {
@@ -9275,12 +9587,12 @@ iseq_compile_each0(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const no
                 ADD_INSN(ret, node, dup);
             }
 
-	    ADD_INSN1(ret, node, putspecialobject,
-		      INT2FIX(VM_SPECIAL_OBJECT_CONST_BASE));
+            ADD_INSN1(ret, node, putspecialobject,
+                      INT2FIX(VM_SPECIAL_OBJECT_CONST_BASE));
             ADD_INSN1(ret, node, setconstant, ID2SYM(node->nd_vid));
-	}
-	else {
-	    compile_cpath(ret, iseq, node->nd_else);
+        }
+        else {
+            compile_cpath(ret, iseq, node->nd_else);
             CHECK(COMPILE(ret, "lvalue", node->nd_value));
             ADD_INSN(ret, node, swap);
 
@@ -9290,32 +9602,32 @@ iseq_compile_each0(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const no
             }
 
             ADD_INSN1(ret, node, setconstant, ID2SYM(node->nd_else->nd_mid));
-	}
-	break;
+        }
+        break;
       }
       case NODE_CVASGN:{
-	CHECK(COMPILE(ret, "cvasgn val", node->nd_value));
-	if (!popped) {
-	    ADD_INSN(ret, node, dup);
-	}
+        CHECK(COMPILE(ret, "cvasgn val", node->nd_value));
+        if (!popped) {
+            ADD_INSN(ret, node, dup);
+        }
         ADD_INSN2(ret, node, setclassvariable,
                   ID2SYM(node->nd_vid),
-                  get_ivar_ic_value(iseq,node->nd_vid));
-	break;
+                  get_cvar_ic_value(iseq,node->nd_vid));
+        break;
       }
       case NODE_OP_ASGN1:
-	CHECK(compile_op_asgn1(iseq, ret, node, popped));
-	break;
+        CHECK(compile_op_asgn1(iseq, ret, node, popped));
+        break;
       case NODE_OP_ASGN2:
-	CHECK(compile_op_asgn2(iseq, ret, node, popped));
-	break;
+        CHECK(compile_op_asgn2(iseq, ret, node, popped));
+        break;
       case NODE_OP_CDECL:
-	CHECK(compile_op_cdecl(iseq, ret, node, popped));
-	break;
+        CHECK(compile_op_cdecl(iseq, ret, node, popped));
+        break;
       case NODE_OP_ASGN_AND:
       case NODE_OP_ASGN_OR:
-	CHECK(compile_op_log(iseq, ret, node, popped, type));
-	break;
+        CHECK(compile_op_log(iseq, ret, node, popped, type));
+        break;
       case NODE_CALL:   /* obj.foo */
       case NODE_OPCALL: /* foo[] */
         if (compile_call_precheck_freeze(iseq, ret, node, node, popped) == TRUE) {
@@ -9330,271 +9642,272 @@ iseq_compile_each0(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const no
         break;
       case NODE_SUPER:
       case NODE_ZSUPER:
-	CHECK(compile_super(iseq, ret, node, popped, type));
-	break;
+        CHECK(compile_super(iseq, ret, node, popped, type));
+        break;
       case NODE_LIST:{
         CHECK(compile_array(iseq, ret, node, popped) >= 0);
-	break;
+        break;
       }
       case NODE_ZLIST:{
-	if (!popped) {
-	    ADD_INSN1(ret, node, newarray, INT2FIX(0));
-	}
-	break;
+        if (!popped) {
+            ADD_INSN1(ret, node, newarray, INT2FIX(0));
+        }
+        break;
       }
       case NODE_VALUES:{
-	const NODE *n = node;
-	if (popped) {
-	    COMPILE_ERROR(ERROR_ARGS "NODE_VALUES: must not be popped");
-	}
-	while (n) {
-	    CHECK(COMPILE(ret, "values item", n->nd_head));
-	    n = n->nd_next;
-	}
-	ADD_INSN1(ret, node, newarray, INT2FIX(node->nd_alen));
-	break;
+        const NODE *n = node;
+        if (popped) {
+            COMPILE_ERROR(ERROR_ARGS "NODE_VALUES: must not be popped");
+        }
+        while (n) {
+            CHECK(COMPILE(ret, "values item", n->nd_head));
+            n = n->nd_next;
+        }
+        ADD_INSN1(ret, node, newarray, INT2FIX(node->nd_alen));
+        break;
       }
       case NODE_HASH:
         CHECK(compile_hash(iseq, ret, node, FALSE, popped) >= 0);
         break;
       case NODE_RETURN:
-	CHECK(compile_return(iseq, ret, node, popped));
-	break;
+        CHECK(compile_return(iseq, ret, node, popped));
+        break;
       case NODE_YIELD:
-	CHECK(compile_yield(iseq, ret, node, popped));
-	break;
+        CHECK(compile_yield(iseq, ret, node, popped));
+        break;
       case NODE_LVAR:{
-	if (!popped) {
-	    compile_lvar(iseq, ret, node, node->nd_vid);
-	}
-	break;
+        if (!popped) {
+            compile_lvar(iseq, ret, node, node->nd_vid);
+        }
+        break;
       }
       case NODE_DVAR:{
-	int lv, idx, ls;
-	debugi("nd_vid", node->nd_vid);
-	if (!popped) {
-	    idx = get_dyna_var_idx(iseq, node->nd_vid, &lv, &ls);
-	    if (idx < 0) {
-		COMPILE_ERROR(ERROR_ARGS "unknown dvar (%"PRIsVALUE")",
-			      rb_id2str(node->nd_vid));
-		goto ng;
-	    }
-	    ADD_GETLOCAL(ret, node, ls - idx, lv);
-	}
-	break;
+        int lv, idx, ls;
+        debugi("nd_vid", node->nd_vid);
+        if (!popped) {
+            idx = get_dyna_var_idx(iseq, node->nd_vid, &lv, &ls);
+            if (idx < 0) {
+                COMPILE_ERROR(ERROR_ARGS "unknown dvar (%"PRIsVALUE")",
+                              rb_id2str(node->nd_vid));
+                goto ng;
+            }
+            ADD_GETLOCAL(ret, node, ls - idx, lv);
+        }
+        break;
       }
       case NODE_GVAR:{
-	ADD_INSN1(ret, node, getglobal, ID2SYM(node->nd_entry));
-	if (popped) {
-	    ADD_INSN(ret, node, pop);
-	}
-	break;
+        ADD_INSN1(ret, node, getglobal, ID2SYM(node->nd_entry));
+        if (popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        break;
       }
       case NODE_IVAR:{
-	debugi("nd_vid", node->nd_vid);
-	if (!popped) {
-	    ADD_INSN2(ret, node, getinstancevariable,
-		      ID2SYM(node->nd_vid),
-		      get_ivar_ic_value(iseq,node->nd_vid));
-	}
-	break;
+        debugi("nd_vid", node->nd_vid);
+        if (!popped) {
+            ADD_INSN2(ret, node, getinstancevariable,
+                      ID2SYM(node->nd_vid),
+                      get_ivar_ic_value(iseq,node->nd_vid));
+        }
+        break;
       }
       case NODE_CONST:{
-	debugi("nd_vid", node->nd_vid);
+        debugi("nd_vid", node->nd_vid);
 
-	if (ISEQ_COMPILE_DATA(iseq)->option->inline_const_cache) {
-	    LABEL *lend = NEW_LABEL(line);
-	    int ic_index = body->is_size++;
-
-            ADD_INSN2(ret, node, opt_getinlinecache, lend, INT2FIX(ic_index));
-            ADD_INSN1(ret, node, putobject, Qtrue);
-            ADD_INSN1(ret, node, getconstant, ID2SYM(node->nd_vid));
-            ADD_INSN1(ret, node, opt_setinlinecache, INT2FIX(ic_index));
-	    ADD_LABEL(ret, lend);
-	}
-	else {
-	    ADD_INSN(ret, node, putnil);
+        if (ISEQ_COMPILE_DATA(iseq)->option->inline_const_cache) {
+            body->ic_size++;
+            VALUE segments = rb_ary_new_from_args(1, ID2SYM(node->nd_vid));
+            ADD_INSN1(ret, node, opt_getconstant_path, segments);
+            RB_OBJ_WRITTEN(iseq, Qundef, segments);
+        }
+        else {
+            ADD_INSN(ret, node, putnil);
             ADD_INSN1(ret, node, putobject, Qtrue);
             ADD_INSN1(ret, node, getconstant, ID2SYM(node->nd_vid));
-	}
+        }
 
-	if (popped) {
-	    ADD_INSN(ret, node, pop);
-	}
-	break;
+        if (popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        break;
       }
       case NODE_CVAR:{
-	if (!popped) {
-	    ADD_INSN2(ret, node, getclassvariable,
-		      ID2SYM(node->nd_vid),
-		      get_ivar_ic_value(iseq,node->nd_vid));
-	}
-	break;
+        if (!popped) {
+            ADD_INSN2(ret, node, getclassvariable,
+                      ID2SYM(node->nd_vid),
+                      get_cvar_ic_value(iseq,node->nd_vid));
+        }
+        break;
       }
       case NODE_NTH_REF:{
         if (!popped) {
-	    if (!node->nd_nth) {
-		ADD_INSN(ret, node, putnil);
-		break;
-	    }
-	    ADD_INSN2(ret, node, getspecial, INT2FIX(1) /* '~'  */,
-		      INT2FIX(node->nd_nth << 1));
-	}
-	break;
+            if (!node->nd_nth) {
+                ADD_INSN(ret, node, putnil);
+                break;
+            }
+            ADD_INSN2(ret, node, getspecial, INT2FIX(1) /* '~'  */,
+                      INT2FIX(node->nd_nth << 1));
+        }
+        break;
       }
       case NODE_BACK_REF:{
-	if (!popped) {
-	    ADD_INSN2(ret, node, getspecial, INT2FIX(1) /* '~' */,
-		      INT2FIX(0x01 | (node->nd_nth << 1)));
-	}
-	break;
+        if (!popped) {
+            ADD_INSN2(ret, node, getspecial, INT2FIX(1) /* '~' */,
+                      INT2FIX(0x01 | (node->nd_nth << 1)));
+        }
+        break;
       }
       case NODE_MATCH:
       case NODE_MATCH2:
       case NODE_MATCH3:
-	CHECK(compile_match(iseq, ret, node, popped, type));
-	break;
+        CHECK(compile_match(iseq, ret, node, popped, type));
+        break;
       case NODE_LIT:{
-	debugp_param("lit", node->nd_lit);
-	if (!popped) {
-	    ADD_INSN1(ret, node, putobject, node->nd_lit);
+        debugp_param("lit", node->nd_lit);
+        if (!popped) {
+            if (UNLIKELY(node->nd_lit == rb_mRubyVMFrozenCore)) {
+                ADD_INSN1(ret, node, putspecialobject, INT2FIX(VM_SPECIAL_OBJECT_VMCORE)); // [Bug #20569]
+            }
+            else {
+                ADD_INSN1(ret, node, putobject, node->nd_lit);
+            }
             RB_OBJ_WRITTEN(iseq, Qundef, node->nd_lit);
-	}
-	break;
+        }
+        break;
       }
       case NODE_STR:{
-	debugp_param("nd_lit", node->nd_lit);
-	if (!popped) {
-	    VALUE lit = node->nd_lit;
-	    if (!ISEQ_COMPILE_DATA(iseq)->option->frozen_string_literal) {
-		lit = rb_fstring(lit);
-		ADD_INSN1(ret, node, putstring, lit);
+        debugp_param("nd_lit", node->nd_lit);
+        if (!popped) {
+            VALUE lit = node->nd_lit;
+            if (!ISEQ_COMPILE_DATA(iseq)->option->frozen_string_literal) {
+                lit = rb_fstring(lit);
+                ADD_INSN1(ret, node, putstring, lit);
                 RB_OBJ_WRITTEN(iseq, Qundef, lit);
-	    }
-	    else {
-		if (ISEQ_COMPILE_DATA(iseq)->option->debug_frozen_string_literal || RTEST(ruby_debug)) {
-		    VALUE debug_info = rb_ary_new_from_args(2, rb_iseq_path(iseq), INT2FIX(line));
-		    lit = rb_str_dup(lit);
-		    rb_ivar_set(lit, id_debug_created_info, rb_obj_freeze(debug_info));
-		    lit = rb_str_freeze(lit);
-		}
-		else {
-		    lit = rb_fstring(lit);
-		}
-		ADD_INSN1(ret, node, putobject, lit);
+            }
+            else {
+                if (ISEQ_COMPILE_DATA(iseq)->option->debug_frozen_string_literal || RTEST(ruby_debug)) {
+                    VALUE debug_info = rb_ary_new_from_args(2, rb_iseq_path(iseq), INT2FIX(line));
+                    lit = rb_str_dup(lit);
+                    rb_ivar_set(lit, id_debug_created_info, rb_obj_freeze(debug_info));
+                    lit = rb_str_freeze(lit);
+                }
+                else {
+                    lit = rb_fstring(lit);
+                }
+                ADD_INSN1(ret, node, putobject, lit);
                 RB_OBJ_WRITTEN(iseq, Qundef, lit);
-	    }
-	}
-	break;
+            }
+        }
+        break;
       }
       case NODE_DSTR:{
-	compile_dstr(iseq, ret, node);
+        compile_dstr(iseq, ret, node);
 
-	if (popped) {
-	    ADD_INSN(ret, node, pop);
-	}
-	break;
+        if (popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        break;
       }
       case NODE_XSTR:{
-	ADD_CALL_RECEIVER(ret, node);
+        ADD_CALL_RECEIVER(ret, node);
         VALUE str = rb_fstring(node->nd_lit);
-	ADD_INSN1(ret, node, putobject, str);
+        ADD_INSN1(ret, node, putobject, str);
         RB_OBJ_WRITTEN(iseq, Qundef, str);
-	ADD_CALL(ret, node, idBackquote, INT2FIX(1));
+        ADD_CALL(ret, node, idBackquote, INT2FIX(1));
 
-	if (popped) {
-	    ADD_INSN(ret, node, pop);
-	}
-	break;
+        if (popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        break;
       }
       case NODE_DXSTR:{
-	ADD_CALL_RECEIVER(ret, node);
-	compile_dstr(iseq, ret, node);
-	ADD_CALL(ret, node, idBackquote, INT2FIX(1));
-
-	if (popped) {
-	    ADD_INSN(ret, node, pop);
-	}
-	break;
+        ADD_CALL_RECEIVER(ret, node);
+        compile_dstr(iseq, ret, node);
+        ADD_CALL(ret, node, idBackquote, INT2FIX(1));
+
+        if (popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        break;
       }
       case NODE_EVSTR:
-	CHECK(compile_evstr(iseq, ret, node->nd_body, popped));
-	break;
+        CHECK(compile_evstr(iseq, ret, node->nd_body, popped));
+        break;
       case NODE_DREGX:{
-	compile_dregx(iseq, ret, node);
+        compile_dregx(iseq, ret, node);
 
-	if (popped) {
-	    ADD_INSN(ret, node, pop);
-	}
-	break;
+        if (popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        break;
       }
       case NODE_ONCE:{
-	int ic_index = body->is_size++;
-	const rb_iseq_t *block_iseq;
-	block_iseq = NEW_CHILD_ISEQ(node->nd_body, make_name_for_block(iseq), ISEQ_TYPE_PLAIN, line);
+        int ic_index = body->ise_size++;
+        const rb_iseq_t *block_iseq;
+        block_iseq = NEW_CHILD_ISEQ(node->nd_body, make_name_for_block(iseq), ISEQ_TYPE_PLAIN, line);
 
-	ADD_INSN2(ret, node, once, block_iseq, INT2FIX(ic_index));
+        ADD_INSN2(ret, node, once, block_iseq, INT2FIX(ic_index));
         RB_OBJ_WRITTEN(iseq, Qundef, (VALUE)block_iseq);
 
-	if (popped) {
-	    ADD_INSN(ret, node, pop);
-	}
-	break;
+        if (popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        break;
       }
       case NODE_ARGSCAT:{
-	if (popped) {
-	    CHECK(COMPILE(ret, "argscat head", node->nd_head));
-	    ADD_INSN1(ret, node, splatarray, Qfalse);
-	    ADD_INSN(ret, node, pop);
-	    CHECK(COMPILE(ret, "argscat body", node->nd_body));
-	    ADD_INSN1(ret, node, splatarray, Qfalse);
-	    ADD_INSN(ret, node, pop);
-	}
-	else {
-	    CHECK(COMPILE(ret, "argscat head", node->nd_head));
-	    CHECK(COMPILE(ret, "argscat body", node->nd_body));
-	    ADD_INSN(ret, node, concatarray);
-	}
-	break;
+        if (popped) {
+            CHECK(COMPILE(ret, "argscat head", node->nd_head));
+            ADD_INSN1(ret, node, splatarray, Qfalse);
+            ADD_INSN(ret, node, pop);
+            CHECK(COMPILE(ret, "argscat body", node->nd_body));
+            ADD_INSN1(ret, node, splatarray, Qfalse);
+            ADD_INSN(ret, node, pop);
+        }
+        else {
+            CHECK(COMPILE(ret, "argscat head", node->nd_head));
+            CHECK(COMPILE(ret, "argscat body", node->nd_body));
+            ADD_INSN(ret, node, concatarray);
+        }
+        break;
       }
       case NODE_ARGSPUSH:{
-	if (popped) {
-	    CHECK(COMPILE(ret, "argspush head", node->nd_head));
-	    ADD_INSN1(ret, node, splatarray, Qfalse);
-	    ADD_INSN(ret, node, pop);
-	    CHECK(COMPILE_(ret, "argspush body", node->nd_body, popped));
-	}
-	else {
-	    CHECK(COMPILE(ret, "argspush head", node->nd_head));
-	    CHECK(compile_array_1(iseq, ret, node->nd_body));
-	    ADD_INSN(ret, node, concatarray);
-	}
-	break;
+        if (popped) {
+            CHECK(COMPILE(ret, "argspush head", node->nd_head));
+            ADD_INSN1(ret, node, splatarray, Qfalse);
+            ADD_INSN(ret, node, pop);
+            CHECK(COMPILE_(ret, "argspush body", node->nd_body, popped));
+        }
+        else {
+            CHECK(COMPILE(ret, "argspush head", node->nd_head));
+            CHECK(compile_array_1(iseq, ret, node->nd_body));
+            ADD_INSN(ret, node, concatarray);
+        }
+        break;
       }
       case NODE_SPLAT:{
-	CHECK(COMPILE(ret, "splat", node->nd_head));
-	ADD_INSN1(ret, node, splatarray, Qtrue);
+        CHECK(COMPILE(ret, "splat", node->nd_head));
+        ADD_INSN1(ret, node, splatarray, Qtrue);
 
-	if (popped) {
-	    ADD_INSN(ret, node, pop);
-	}
-	break;
+        if (popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        break;
       }
       case NODE_DEFN:{
         ID mid = node->nd_mid;
-	const rb_iseq_t *method_iseq = NEW_ISEQ(node->nd_defn,
+        const rb_iseq_t *method_iseq = NEW_ISEQ(node->nd_defn,
                                                 rb_id2str(mid),
-						ISEQ_TYPE_METHOD, line);
+                                                ISEQ_TYPE_METHOD, line);
 
-	debugp_param("defn/iseq", rb_iseqw_new(method_iseq));
+        debugp_param("defn/iseq", rb_iseqw_new(method_iseq));
         ADD_INSN2(ret, node, definemethod, ID2SYM(mid), method_iseq);
         RB_OBJ_WRITTEN(iseq, Qundef, (VALUE)method_iseq);
 
         if (!popped) {
             ADD_INSN1(ret, node, putobject, ID2SYM(mid));
-	}
+        }
 
-	break;
+        break;
       }
       case NODE_DEFS:{
         ID mid = node->nd_mid;
@@ -9610,206 +9923,206 @@ iseq_compile_each0(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const no
         if (!popped) {
             ADD_INSN1(ret, node, putobject, ID2SYM(mid));
         }
-	break;
+        break;
       }
       case NODE_ALIAS:{
-	ADD_INSN1(ret, node, putspecialobject, INT2FIX(VM_SPECIAL_OBJECT_VMCORE));
-	ADD_INSN1(ret, node, putspecialobject, INT2FIX(VM_SPECIAL_OBJECT_CBASE));
-	CHECK(COMPILE(ret, "alias arg1", node->nd_1st));
-	CHECK(COMPILE(ret, "alias arg2", node->nd_2nd));
-	ADD_SEND(ret, node, id_core_set_method_alias, INT2FIX(3));
-
-	if (popped) {
-	    ADD_INSN(ret, node, pop);
-	}
-	break;
+        ADD_INSN1(ret, node, putspecialobject, INT2FIX(VM_SPECIAL_OBJECT_VMCORE));
+        ADD_INSN1(ret, node, putspecialobject, INT2FIX(VM_SPECIAL_OBJECT_CBASE));
+        CHECK(COMPILE(ret, "alias arg1", node->nd_1st));
+        CHECK(COMPILE(ret, "alias arg2", node->nd_2nd));
+        ADD_SEND(ret, node, id_core_set_method_alias, INT2FIX(3));
+
+        if (popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        break;
       }
       case NODE_VALIAS:{
-	ADD_INSN1(ret, node, putspecialobject, INT2FIX(VM_SPECIAL_OBJECT_VMCORE));
-	ADD_INSN1(ret, node, putobject, ID2SYM(node->nd_alias));
-	ADD_INSN1(ret, node, putobject, ID2SYM(node->nd_orig));
-	ADD_SEND(ret, node, id_core_set_variable_alias, INT2FIX(2));
-
-	if (popped) {
-	    ADD_INSN(ret, node, pop);
-	}
-	break;
+        ADD_INSN1(ret, node, putspecialobject, INT2FIX(VM_SPECIAL_OBJECT_VMCORE));
+        ADD_INSN1(ret, node, putobject, ID2SYM(node->nd_alias));
+        ADD_INSN1(ret, node, putobject, ID2SYM(node->nd_orig));
+        ADD_SEND(ret, node, id_core_set_variable_alias, INT2FIX(2));
+
+        if (popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        break;
       }
       case NODE_UNDEF:{
-	ADD_INSN1(ret, node, putspecialobject, INT2FIX(VM_SPECIAL_OBJECT_VMCORE));
-	ADD_INSN1(ret, node, putspecialobject, INT2FIX(VM_SPECIAL_OBJECT_CBASE));
-	CHECK(COMPILE(ret, "undef arg", node->nd_undef));
-	ADD_SEND(ret, node, id_core_undef_method, INT2FIX(2));
-
-	if (popped) {
-	    ADD_INSN(ret, node, pop);
-	}
-	break;
+        ADD_INSN1(ret, node, putspecialobject, INT2FIX(VM_SPECIAL_OBJECT_VMCORE));
+        ADD_INSN1(ret, node, putspecialobject, INT2FIX(VM_SPECIAL_OBJECT_CBASE));
+        CHECK(COMPILE(ret, "undef arg", node->nd_undef));
+        ADD_SEND(ret, node, id_core_undef_method, INT2FIX(2));
+
+        if (popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        break;
       }
       case NODE_CLASS:{
-	const rb_iseq_t *class_iseq = NEW_CHILD_ISEQ(node->nd_body,
-						     rb_str_freeze(rb_sprintf("<class:%"PRIsVALUE">", rb_id2str(node->nd_cpath->nd_mid))),
-						     ISEQ_TYPE_CLASS, line);
-	const int flags = VM_DEFINECLASS_TYPE_CLASS |
-	    (node->nd_super ? VM_DEFINECLASS_FLAG_HAS_SUPERCLASS : 0) |
-	    compile_cpath(ret, iseq, node->nd_cpath);
-
-	CHECK(COMPILE(ret, "super", node->nd_super));
-	ADD_INSN3(ret, node, defineclass, ID2SYM(node->nd_cpath->nd_mid), class_iseq, INT2FIX(flags));
+        const rb_iseq_t *class_iseq = NEW_CHILD_ISEQ(node->nd_body,
+                                                     rb_str_freeze(rb_sprintf("<class:%"PRIsVALUE">", rb_id2str(node->nd_cpath->nd_mid))),
+                                                     ISEQ_TYPE_CLASS, line);
+        const int flags = VM_DEFINECLASS_TYPE_CLASS |
+            (node->nd_super ? VM_DEFINECLASS_FLAG_HAS_SUPERCLASS : 0) |
+            compile_cpath(ret, iseq, node->nd_cpath);
+
+        CHECK(COMPILE(ret, "super", node->nd_super));
+        ADD_INSN3(ret, node, defineclass, ID2SYM(node->nd_cpath->nd_mid), class_iseq, INT2FIX(flags));
         RB_OBJ_WRITTEN(iseq, Qundef, (VALUE)class_iseq);
 
-	if (popped) {
-	    ADD_INSN(ret, node, pop);
-	}
-	break;
+        if (popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        break;
       }
       case NODE_MODULE:{
         const rb_iseq_t *module_iseq = NEW_CHILD_ISEQ(node->nd_body,
-						      rb_str_freeze(rb_sprintf("<module:%"PRIsVALUE">", rb_id2str(node->nd_cpath->nd_mid))),
-						      ISEQ_TYPE_CLASS, line);
-	const int flags = VM_DEFINECLASS_TYPE_MODULE |
-	    compile_cpath(ret, iseq, node->nd_cpath);
+                                                      rb_str_freeze(rb_sprintf("<module:%"PRIsVALUE">", rb_id2str(node->nd_cpath->nd_mid))),
+                                                      ISEQ_TYPE_CLASS, line);
+        const int flags = VM_DEFINECLASS_TYPE_MODULE |
+            compile_cpath(ret, iseq, node->nd_cpath);
 
-	ADD_INSN (ret, node, putnil); /* dummy */
-	ADD_INSN3(ret, node, defineclass, ID2SYM(node->nd_cpath->nd_mid), module_iseq, INT2FIX(flags));
+        ADD_INSN (ret, node, putnil); /* dummy */
+        ADD_INSN3(ret, node, defineclass, ID2SYM(node->nd_cpath->nd_mid), module_iseq, INT2FIX(flags));
         RB_OBJ_WRITTEN(iseq, Qundef, (VALUE)module_iseq);
 
-	if (popped) {
-	    ADD_INSN(ret, node, pop);
-	}
-	break;
+        if (popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        break;
       }
       case NODE_SCLASS:{
-	ID singletonclass;
-	const rb_iseq_t *singleton_class = NEW_ISEQ(node->nd_body, rb_fstring_lit("singleton class"),
-						    ISEQ_TYPE_CLASS, line);
-
-	CHECK(COMPILE(ret, "sclass#recv", node->nd_recv));
-	ADD_INSN (ret, node, putnil);
-	CONST_ID(singletonclass, "singletonclass");
-	ADD_INSN3(ret, node, defineclass,
-		  ID2SYM(singletonclass), singleton_class,
-		  INT2FIX(VM_DEFINECLASS_TYPE_SINGLETON_CLASS));
+        ID singletonclass;
+        const rb_iseq_t *singleton_class = NEW_ISEQ(node->nd_body, rb_fstring_lit("singleton class"),
+                                                    ISEQ_TYPE_CLASS, line);
+
+        CHECK(COMPILE(ret, "sclass#recv", node->nd_recv));
+        ADD_INSN (ret, node, putnil);
+        CONST_ID(singletonclass, "singletonclass");
+        ADD_INSN3(ret, node, defineclass,
+                  ID2SYM(singletonclass), singleton_class,
+                  INT2FIX(VM_DEFINECLASS_TYPE_SINGLETON_CLASS));
         RB_OBJ_WRITTEN(iseq, Qundef, (VALUE)singleton_class);
 
-	if (popped) {
-	    ADD_INSN(ret, node, pop);
-	}
-	break;
+        if (popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        break;
       }
       case NODE_COLON2:
-	CHECK(compile_colon2(iseq, ret, node, popped));
-	break;
+        CHECK(compile_colon2(iseq, ret, node, popped));
+        break;
       case NODE_COLON3:
-	CHECK(compile_colon3(iseq, ret, node, popped));
-	break;
+        CHECK(compile_colon3(iseq, ret, node, popped));
+        break;
       case NODE_DOT2:
-	CHECK(compile_dots(iseq, ret, node, popped, FALSE));
-	break;
+        CHECK(compile_dots(iseq, ret, node, popped, FALSE));
+        break;
       case NODE_DOT3:
-	CHECK(compile_dots(iseq, ret, node, popped, TRUE));
-	break;
+        CHECK(compile_dots(iseq, ret, node, popped, TRUE));
+        break;
       case NODE_FLIP2:
       case NODE_FLIP3:{
-	LABEL *lend = NEW_LABEL(line);
-	LABEL *ltrue = NEW_LABEL(line);
-	LABEL *lfalse = NEW_LABEL(line);
-	CHECK(compile_flip_flop(iseq, ret, node, type == NODE_FLIP2,
-				ltrue, lfalse));
-	ADD_LABEL(ret, ltrue);
-	ADD_INSN1(ret, node, putobject, Qtrue);
-	ADD_INSNL(ret, node, jump, lend);
-	ADD_LABEL(ret, lfalse);
-	ADD_INSN1(ret, node, putobject, Qfalse);
-	ADD_LABEL(ret, lend);
-	break;
+        LABEL *lend = NEW_LABEL(line);
+        LABEL *ltrue = NEW_LABEL(line);
+        LABEL *lfalse = NEW_LABEL(line);
+        CHECK(compile_flip_flop(iseq, ret, node, type == NODE_FLIP2,
+                                ltrue, lfalse));
+        ADD_LABEL(ret, ltrue);
+        ADD_INSN1(ret, node, putobject, Qtrue);
+        ADD_INSNL(ret, node, jump, lend);
+        ADD_LABEL(ret, lfalse);
+        ADD_INSN1(ret, node, putobject, Qfalse);
+        ADD_LABEL(ret, lend);
+        break;
       }
       case NODE_SELF:{
-	if (!popped) {
-	    ADD_INSN(ret, node, putself);
-	}
-	break;
+        if (!popped) {
+            ADD_INSN(ret, node, putself);
+        }
+        break;
       }
       case NODE_NIL:{
-	if (!popped) {
-	    ADD_INSN(ret, node, putnil);
-	}
-	break;
+        if (!popped) {
+            ADD_INSN(ret, node, putnil);
+        }
+        break;
       }
       case NODE_TRUE:{
-	if (!popped) {
-	    ADD_INSN1(ret, node, putobject, Qtrue);
-	}
-	break;
+        if (!popped) {
+            ADD_INSN1(ret, node, putobject, Qtrue);
+        }
+        break;
       }
       case NODE_FALSE:{
-	if (!popped) {
-	    ADD_INSN1(ret, node, putobject, Qfalse);
-	}
-	break;
+        if (!popped) {
+            ADD_INSN1(ret, node, putobject, Qfalse);
+        }
+        break;
       }
       case NODE_ERRINFO:
-	CHECK(compile_errinfo(iseq, ret, node, popped));
-	break;
+        CHECK(compile_errinfo(iseq, ret, node, popped));
+        break;
       case NODE_DEFINED:
-	if (!popped) {
-	    CHECK(compile_defined_expr(iseq, ret, node, Qtrue));
-	}
-	break;
+        if (!popped) {
+            CHECK(compile_defined_expr(iseq, ret, node, Qtrue));
+        }
+        break;
       case NODE_POSTEXE:{
-	/* compiled to:
-	 *   ONCE{ rb_mRubyVMFrozenCore::core#set_postexe{ ... } }
-	 */
-	int is_index = body->is_size++;
+        /* compiled to:
+         *   ONCE{ rb_mRubyVMFrozenCore::core#set_postexe{ ... } }
+         */
+        int is_index = body->ise_size++;
         struct rb_iseq_new_with_callback_callback_func *ifunc =
             rb_iseq_new_with_callback_new_callback(build_postexe_iseq, node->nd_body);
-	const rb_iseq_t *once_iseq =
+        const rb_iseq_t *once_iseq =
             new_child_iseq_with_callback(iseq, ifunc,
-				 rb_fstring(make_name_for_block(iseq)), iseq, ISEQ_TYPE_BLOCK, line);
+                                 rb_fstring(make_name_for_block(iseq)), iseq, ISEQ_TYPE_BLOCK, line);
 
-	ADD_INSN2(ret, node, once, once_iseq, INT2FIX(is_index));
+        ADD_INSN2(ret, node, once, once_iseq, INT2FIX(is_index));
         RB_OBJ_WRITTEN(iseq, Qundef, (VALUE)once_iseq);
 
-	if (popped) {
-	    ADD_INSN(ret, node, pop);
-	}
-	break;
+        if (popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        break;
       }
       case NODE_KW_ARG:
-	CHECK(compile_kw_arg(iseq, ret, node, popped));
-	break;
+        CHECK(compile_kw_arg(iseq, ret, node, popped));
+        break;
       case NODE_DSYM:{
-	compile_dstr(iseq, ret, node);
-	if (!popped) {
-	    ADD_INSN(ret, node, intern);
-	}
-	else {
-	    ADD_INSN(ret, node, pop);
-	}
-	break;
+        compile_dstr(iseq, ret, node);
+        if (!popped) {
+            ADD_INSN(ret, node, intern);
+        }
+        else {
+            ADD_INSN(ret, node, pop);
+        }
+        break;
       }
       case NODE_ATTRASGN:
-	CHECK(compile_attrasgn(iseq, ret, node, popped));
-	break;
+        CHECK(compile_attrasgn(iseq, ret, node, popped));
+        break;
       case NODE_LAMBDA:{
-	/* compile same as lambda{...} */
-	const rb_iseq_t *block = NEW_CHILD_ISEQ(node->nd_body, make_name_for_block(iseq), ISEQ_TYPE_BLOCK, line);
-	VALUE argc = INT2FIX(0);
+        /* compile same as lambda{...} */
+        const rb_iseq_t *block = NEW_CHILD_ISEQ(node->nd_body, make_name_for_block(iseq), ISEQ_TYPE_BLOCK, line);
+        VALUE argc = INT2FIX(0);
 
-	ADD_INSN1(ret, node, putspecialobject, INT2FIX(VM_SPECIAL_OBJECT_VMCORE));
-	ADD_CALL_WITH_BLOCK(ret, node, idLambda, argc, block);
+        ADD_INSN1(ret, node, putspecialobject, INT2FIX(VM_SPECIAL_OBJECT_VMCORE));
+        ADD_CALL_WITH_BLOCK(ret, node, idLambda, argc, block);
         RB_OBJ_WRITTEN(iseq, Qundef, (VALUE)block);
 
-	if (popped) {
-	    ADD_INSN(ret, node, pop);
-	}
-	break;
+        if (popped) {
+            ADD_INSN(ret, node, pop);
+        }
+        break;
       }
       default:
-	UNKNOWN_NODE("iseq_compile_each", node, COMPILE_NG);
+        UNKNOWN_NODE("iseq_compile_each", node, COMPILE_NG);
       ng:
-	debug_node_end();
-	return COMPILE_NG;
+        debug_node_end();
+        return COMPILE_NG;
     }
 
     debug_node_end();
@@ -9837,15 +10150,15 @@ opobj_inspect(VALUE obj)
 {
     if (!SPECIAL_CONST_P(obj) && !RBASIC_CLASS(obj)) {
         switch (BUILTIN_TYPE(obj)) {
-	  case T_STRING:
-	    obj = rb_str_new_cstr(RSTRING_PTR(obj));
-	    break;
-	  case T_ARRAY:
-	    obj = rb_ary_dup(obj);
-	    break;
+          case T_STRING:
+            obj = rb_str_new_cstr(RSTRING_PTR(obj));
+            break;
+          case T_ARRAY:
+            obj = rb_ary_dup(obj);
+            break;
           default:
             break;
-	}
+        }
     }
     return rb_inspect(obj);
 }
@@ -9858,86 +10171,92 @@ insn_data_to_s_detail(INSN *iobj)
     VALUE str = rb_sprintf("%-20s ", insn_name(iobj->insn_id));
 
     if (iobj->operands) {
-	const char *types = insn_op_types(iobj->insn_id);
-	int j;
-
-	for (j = 0; types[j]; j++) {
-	    char type = types[j];
-
-	    switch (type) {
-	      case TS_OFFSET:	/* label(destination position) */
-		{
-		    LABEL *lobj = (LABEL *)OPERAND_AT(iobj, j);
-		    rb_str_catf(str, LABEL_FORMAT, lobj->label_no);
-		    break;
-		}
-		break;
-	      case TS_ISEQ:	/* iseq */
-		{
-		    rb_iseq_t *iseq = (rb_iseq_t *)OPERAND_AT(iobj, j);
-		    VALUE val = Qnil;
-		    if (0 && iseq) { /* TODO: invalidate now */
-			val = (VALUE)iseq;
-		    }
-		    rb_str_concat(str, opobj_inspect(val));
-		}
-		break;
-	      case TS_LINDEX:
-	      case TS_NUM:	/* ulong */
-	      case TS_VALUE:	/* VALUE */
-		{
-		    VALUE v = OPERAND_AT(iobj, j);
+        const char *types = insn_op_types(iobj->insn_id);
+        int j;
+
+        for (j = 0; types[j]; j++) {
+            char type = types[j];
+
+            switch (type) {
+              case TS_OFFSET:	/* label(destination position) */
+                {
+                    LABEL *lobj = (LABEL *)OPERAND_AT(iobj, j);
+                    rb_str_catf(str, LABEL_FORMAT, lobj->label_no);
+                    break;
+                }
+                break;
+              case TS_ISEQ:	/* iseq */
+                {
+                    rb_iseq_t *iseq = (rb_iseq_t *)OPERAND_AT(iobj, j);
+                    VALUE val = Qnil;
+                    if (0 && iseq) { /* TODO: invalidate now */
+                        val = (VALUE)iseq;
+                    }
+                    rb_str_concat(str, opobj_inspect(val));
+                }
+                break;
+              case TS_LINDEX:
+              case TS_NUM:	/* ulong */
+              case TS_VALUE:	/* VALUE */
+                {
+                    VALUE v = OPERAND_AT(iobj, j);
                     if (!CLASS_OF(v))
                         rb_str_cat2(str, "<hidden>");
                     else {
                         rb_str_concat(str, opobj_inspect(v));
                     }
-		    break;
-		}
-	      case TS_ID:	/* ID */
-		rb_str_concat(str, opobj_inspect(OPERAND_AT(iobj, j)));
-		break;
-	      case TS_IC:	/* inline cache */
-	      case TS_IVC:	/* inline ivar cache */
-	      case TS_ICVARC:   /* inline cvar cache */
-	      case TS_ISE:	/* inline storage entry */
-		rb_str_catf(str, "<ic:%d>", FIX2INT(OPERAND_AT(iobj, j)));
-		break;
+                    break;
+                }
+              case TS_ID:	/* ID */
+                rb_str_concat(str, opobj_inspect(OPERAND_AT(iobj, j)));
+                break;
+              case TS_IC:	/* inline cache */
+                rb_str_concat(str, opobj_inspect(OPERAND_AT(iobj, j)));
+                break;
+              case TS_IVC:	/* inline ivar cache */
+                rb_str_catf(str, "<ivc:%d>", FIX2INT(OPERAND_AT(iobj, j)));
+                break;
+              case TS_ICVARC:   /* inline cvar cache */
+                rb_str_catf(str, "<icvarc:%d>", FIX2INT(OPERAND_AT(iobj, j)));
+                break;
+              case TS_ISE:	/* inline storage entry */
+                rb_str_catf(str, "<ise:%d>", FIX2INT(OPERAND_AT(iobj, j)));
+                break;
               case TS_CALLDATA: /* we store these as call infos at compile time */
-		{
+                {
                     const struct rb_callinfo *ci = (struct rb_callinfo *)OPERAND_AT(iobj, j);
                     rb_str_cat2(str, "<calldata:");
                     if (vm_ci_mid(ci)) rb_str_catf(str, "%"PRIsVALUE, rb_id2str(vm_ci_mid(ci)));
                     rb_str_catf(str, ", %d>", vm_ci_argc(ci));
-		    break;
-		}
-	      case TS_CDHASH:	/* case/when condition cache */
-		rb_str_cat2(str, "<ch>");
-		break;
-	      case TS_FUNCPTR:
-		{
-		    void *func = (void *)OPERAND_AT(iobj, j);
+                    break;
+                }
+              case TS_CDHASH:	/* case/when condition cache */
+                rb_str_cat2(str, "<ch>");
+                break;
+              case TS_FUNCPTR:
+                {
+                    void *func = (void *)OPERAND_AT(iobj, j);
 #ifdef HAVE_DLADDR
-		    Dl_info info;
-		    if (dladdr(func, &info) && info.dli_sname) {
-			rb_str_cat2(str, info.dli_sname);
-			break;
-		    }
+                    Dl_info info;
+                    if (dladdr(func, &info) && info.dli_sname) {
+                        rb_str_cat2(str, info.dli_sname);
+                        break;
+                    }
 #endif
-		    rb_str_catf(str, "<%p>", func);
-		}
-		break;
+                    rb_str_catf(str, "<%p>", func);
+                }
+                break;
               case TS_BUILTIN:
                 rb_str_cat2(str, "<TS_BUILTIN>");
                 break;
-	      default:{
-		rb_raise(rb_eSyntaxError, "unknown operand type: %c", type);
-	      }
-	    }
-	    if (types[j + 1]) {
-		rb_str_cat2(str, ", ");
-	    }
-	}
+              default:{
+                rb_raise(rb_eSyntaxError, "unknown operand type: %c", type);
+              }
+            }
+            if (types[j + 1]) {
+                rb_str_cat2(str, ", ");
+            }
+        }
     }
     return str;
 }
@@ -9959,40 +10278,40 @@ dump_disasm_list_with_cursor(const LINK_ELEMENT *link, const LINK_ELEMENT *curr,
     printf("-- raw disasm--------\n");
 
     while (link) {
-	if (curr) printf(curr == link ? "*" : " ");
-	switch (link->type) {
-	  case ISEQ_ELEMENT_INSN:
-	    {
-		iobj = (INSN *)link;
-		str = insn_data_to_s_detail(iobj);
-		printf("  %04d %-65s(%4u)\n", pos, StringValueCStr(str), iobj->insn_info.line_no);
-		pos += insn_data_length(iobj);
-		break;
-	    }
-	  case ISEQ_ELEMENT_LABEL:
-	    {
-		lobj = (LABEL *)link;
-		printf(LABEL_FORMAT" [sp: %d]%s\n", lobj->label_no, lobj->sp,
-		       dest == lobj ? " <---" : "");
-		break;
-	    }
-	  case ISEQ_ELEMENT_TRACE:
-	    {
-		TRACE *trace = (TRACE *)link;
-		printf("  trace: %0x\n", trace->event);
-		break;
-	    }
-	  case ISEQ_ELEMENT_ADJUST:
-	    {
-		ADJUST *adjust = (ADJUST *)link;
-		printf("  adjust: [label: %d]\n", adjust->label ? adjust->label->label_no : -1);
-		break;
-	    }
-	  default:
-	    /* ignore */
-	    rb_raise(rb_eSyntaxError, "dump_disasm_list error: %ld\n", FIX2LONG(link->type));
-	}
-	link = link->next;
+        if (curr) printf(curr == link ? "*" : " ");
+        switch (link->type) {
+          case ISEQ_ELEMENT_INSN:
+            {
+                iobj = (INSN *)link;
+                str = insn_data_to_s_detail(iobj);
+                printf("  %04d %-65s(%4u)\n", pos, StringValueCStr(str), iobj->insn_info.line_no);
+                pos += insn_data_length(iobj);
+                break;
+            }
+          case ISEQ_ELEMENT_LABEL:
+            {
+                lobj = (LABEL *)link;
+                printf(LABEL_FORMAT" [sp: %d]%s\n", lobj->label_no, lobj->sp,
+                       dest == lobj ? " <---" : "");
+                break;
+            }
+          case ISEQ_ELEMENT_TRACE:
+            {
+                TRACE *trace = (TRACE *)link;
+                printf("  trace: %0x\n", trace->event);
+                break;
+            }
+          case ISEQ_ELEMENT_ADJUST:
+            {
+                ADJUST *adjust = (ADJUST *)link;
+                printf("  adjust: [label: %d]\n", adjust->label ? adjust->label->label_no : -1);
+                break;
+            }
+          default:
+            /* ignore */
+            rb_raise(rb_eSyntaxError, "dump_disasm_list error: %ld\n", FIX2LONG(link->type));
+        }
+        link = link->next;
     }
     printf("---------------------\n");
     fflush(stdout);
@@ -10010,7 +10329,7 @@ rb_insns_name_array(void)
     VALUE ary = rb_ary_new_capa(VM_INSTRUCTION_SIZE);
     int i;
     for (i = 0; i < VM_INSTRUCTION_SIZE; i++) {
-	rb_ary_push(ary, rb_fstring_cstr(insn_name(i)));
+        rb_ary_push(ary, rb_fstring_cstr(insn_name(i)));
     }
     return rb_obj_freeze(ary);
 }
@@ -10023,11 +10342,11 @@ register_label(rb_iseq_t *iseq, struct st_table *labels_table, VALUE obj)
     obj = rb_to_symbol_type(obj);
 
     if (st_lookup(labels_table, obj, &tmp) == 0) {
-	label = NEW_LABEL(0);
-	st_insert(labels_table, obj, (st_data_t)label);
+        label = NEW_LABEL(0);
+        st_insert(labels_table, obj, (st_data_t)label);
     }
     else {
-	label = (LABEL *)tmp;
+        label = (LABEL *)tmp;
     }
     LABEL_REF(label);
     return label;
@@ -10040,12 +10359,12 @@ get_exception_sym2type(VALUE sym)
     static VALUE symBreak, symRedo, symNext;
 
     if (symRescue == 0) {
-	symRescue = ID2SYM(rb_intern_const("rescue"));
-	symEnsure = ID2SYM(rb_intern_const("ensure"));
-	symRetry  = ID2SYM(rb_intern_const("retry"));
-	symBreak  = ID2SYM(rb_intern_const("break"));
-	symRedo   = ID2SYM(rb_intern_const("redo"));
-	symNext   = ID2SYM(rb_intern_const("next"));
+        symRescue = ID2SYM(rb_intern_const("rescue"));
+        symEnsure = ID2SYM(rb_intern_const("ensure"));
+        symRetry  = ID2SYM(rb_intern_const("retry"));
+        symBreak  = ID2SYM(rb_intern_const("break"));
+        symRedo   = ID2SYM(rb_intern_const("redo"));
+        symNext   = ID2SYM(rb_intern_const("next"));
     }
 
     if (sym == symRescue) return CATCH_TYPE_RESCUE;
@@ -10060,25 +10379,25 @@ get_exception_sym2type(VALUE sym)
 
 static int
 iseq_build_from_ary_exception(rb_iseq_t *iseq, struct st_table *labels_table,
-		     VALUE exception)
+                     VALUE exception)
 {
     int i;
 
     for (i=0; i<RARRAY_LEN(exception); i++) {
-	const rb_iseq_t *eiseq;
-	VALUE v, type;
-	LABEL *lstart, *lend, *lcont;
-	unsigned int sp;
-
-	v = rb_to_array_type(RARRAY_AREF(exception, i));
-	if (RARRAY_LEN(v) != 6) {
-	    rb_raise(rb_eSyntaxError, "wrong exception entry");
-	}
+        const rb_iseq_t *eiseq;
+        VALUE v, type;
+        LABEL *lstart, *lend, *lcont;
+        unsigned int sp;
+
+        v = rb_to_array_type(RARRAY_AREF(exception, i));
+        if (RARRAY_LEN(v) != 6) {
+            rb_raise(rb_eSyntaxError, "wrong exception entry");
+        }
         type = get_exception_sym2type(RARRAY_AREF(v, 0));
         if (NIL_P(RARRAY_AREF(v, 1))) {
-	    eiseq = NULL;
-	}
-	else {
+            eiseq = NULL;
+        }
+        else {
             eiseq = rb_iseqw_to_iseq(rb_iseq_load(RARRAY_AREF(v, 1), (VALUE)iseq, Qnil));
         }
 
@@ -10087,18 +10406,18 @@ iseq_build_from_ary_exception(rb_iseq_t *iseq, struct st_table *labels_table,
         lcont  = register_label(iseq, labels_table, RARRAY_AREF(v, 4));
         sp     = NUM2UINT(RARRAY_AREF(v, 5));
 
-	/* TODO: Dirty Hack!  Fix me */
-	if (type == CATCH_TYPE_RESCUE ||
-	    type == CATCH_TYPE_BREAK ||
-	    type == CATCH_TYPE_NEXT) {
-	    ++sp;
-	}
+        /* TODO: Dirty Hack!  Fix me */
+        if (type == CATCH_TYPE_RESCUE ||
+            type == CATCH_TYPE_BREAK ||
+            type == CATCH_TYPE_NEXT) {
+            ++sp;
+        }
 
-	lcont->sp = sp;
+        lcont->sp = sp;
 
-	ADD_CATCH_ENTRY(type, lstart, lend, eiseq, lcont);
+        ADD_CATCH_ENTRY(type, lstart, lend, eiseq, lcont);
 
-	RB_GC_GUARD(v);
+        RB_GC_GUARD(v);
     }
     return COMPILE_OK;
 }
@@ -10111,7 +10430,7 @@ insn_make_insn_table(void)
     table = st_init_numtable_with_size(VM_INSTRUCTION_SIZE);
 
     for (i=0; i<VM_INSTRUCTION_SIZE; i++) {
-	st_insert(table, ID2SYM(rb_intern_const(insn_name(i))), i);
+        st_insert(table, ID2SYM(rb_intern_const(insn_name(i))), i);
     }
 
     return table;
@@ -10124,13 +10443,13 @@ iseq_build_load_iseq(const rb_iseq_t *iseq, VALUE op)
     const rb_iseq_t *loaded_iseq;
 
     if (RB_TYPE_P(op, T_ARRAY)) {
-	iseqw = rb_iseq_load(op, (VALUE)iseq, Qnil);
+        iseqw = rb_iseq_load(op, (VALUE)iseq, Qnil);
     }
     else if (CLASS_OF(op) == rb_cISeq) {
-	iseqw = op;
+        iseqw = op;
     }
     else {
-	rb_raise(rb_eSyntaxError, "ISEQ is required");
+        rb_raise(rb_eSyntaxError, "ISEQ is required");
     }
 
     loaded_iseq = rb_iseqw_to_iseq(iseqw);
@@ -10146,28 +10465,28 @@ iseq_build_callinfo_from_hash(rb_iseq_t *iseq, VALUE op)
     struct rb_callinfo_kwarg *kw_arg = 0;
 
     if (!NIL_P(op)) {
-	VALUE vmid = rb_hash_aref(op, ID2SYM(rb_intern_const("mid")));
-	VALUE vflag = rb_hash_aref(op, ID2SYM(rb_intern_const("flag")));
-	VALUE vorig_argc = rb_hash_aref(op, ID2SYM(rb_intern_const("orig_argc")));
-	VALUE vkw_arg = rb_hash_aref(op, ID2SYM(rb_intern_const("kw_arg")));
-
-	if (!NIL_P(vmid)) mid = SYM2ID(vmid);
-	if (!NIL_P(vflag)) flag = NUM2UINT(vflag);
-	if (!NIL_P(vorig_argc)) orig_argc = FIX2INT(vorig_argc);
-
-	if (!NIL_P(vkw_arg)) {
-	    int i;
-	    int len = RARRAY_LENINT(vkw_arg);
-	    size_t n = rb_callinfo_kwarg_bytes(len);
-
-	    kw_arg = xmalloc(n);
-	    kw_arg->keyword_len = len;
-	    for (i = 0; i < len; i++) {
-		VALUE kw = RARRAY_AREF(vkw_arg, i);
-		SYM2ID(kw);	/* make immortal */
-		kw_arg->keywords[i] = kw;
-	    }
-	}
+        VALUE vmid = rb_hash_aref(op, ID2SYM(rb_intern_const("mid")));
+        VALUE vflag = rb_hash_aref(op, ID2SYM(rb_intern_const("flag")));
+        VALUE vorig_argc = rb_hash_aref(op, ID2SYM(rb_intern_const("orig_argc")));
+        VALUE vkw_arg = rb_hash_aref(op, ID2SYM(rb_intern_const("kw_arg")));
+
+        if (!NIL_P(vmid)) mid = SYM2ID(vmid);
+        if (!NIL_P(vflag)) flag = NUM2UINT(vflag);
+        if (!NIL_P(vorig_argc)) orig_argc = FIX2INT(vorig_argc);
+
+        if (!NIL_P(vkw_arg)) {
+            int i;
+            int len = RARRAY_LENINT(vkw_arg);
+            size_t n = rb_callinfo_kwarg_bytes(len);
+
+            kw_arg = xmalloc(n);
+            kw_arg->keyword_len = len;
+            for (i = 0; i < len; i++) {
+                VALUE kw = RARRAY_AREF(vkw_arg, i);
+                SYM2ID(kw);	/* make immortal */
+                kw_arg->keywords[i] = kw;
+            }
+        }
     }
 
     const struct rb_callinfo *ci = new_callinfo(iseq, mid, orig_argc, flag, kw_arg, (flag & VM_CALL_ARGS_SIMPLE) == 0);
@@ -10179,20 +10498,20 @@ static rb_event_flag_t
 event_name_to_flag(VALUE sym)
 {
 #define CHECK_EVENT(ev) if (sym == ID2SYM(rb_intern_const(#ev))) return ev;
-		CHECK_EVENT(RUBY_EVENT_LINE);
-		CHECK_EVENT(RUBY_EVENT_CLASS);
-		CHECK_EVENT(RUBY_EVENT_END);
-		CHECK_EVENT(RUBY_EVENT_CALL);
-		CHECK_EVENT(RUBY_EVENT_RETURN);
-		CHECK_EVENT(RUBY_EVENT_B_CALL);
-		CHECK_EVENT(RUBY_EVENT_B_RETURN);
+                CHECK_EVENT(RUBY_EVENT_LINE);
+                CHECK_EVENT(RUBY_EVENT_CLASS);
+                CHECK_EVENT(RUBY_EVENT_END);
+                CHECK_EVENT(RUBY_EVENT_CALL);
+                CHECK_EVENT(RUBY_EVENT_RETURN);
+                CHECK_EVENT(RUBY_EVENT_B_CALL);
+                CHECK_EVENT(RUBY_EVENT_B_RETURN);
 #undef CHECK_EVENT
     return RUBY_EVENT_NONE;
 }
 
 static int
 iseq_build_from_ary_body(rb_iseq_t *iseq, LINK_ANCHOR *const anchor,
-			 VALUE body, VALUE node_ids, VALUE labels_wrapper)
+                         VALUE body, VALUE node_ids, VALUE labels_wrapper)
 {
     /* TODO: body should be frozen */
     long i, len = RARRAY_LEN(body);
@@ -10207,52 +10526,52 @@ iseq_build_from_ary_body(rb_iseq_t *iseq, LINK_ANCHOR *const anchor,
     static struct st_table *insn_table;
 
     if (insn_table == 0) {
-	insn_table = insn_make_insn_table();
+        insn_table = insn_make_insn_table();
     }
 
     for (i=0; i<len; i++) {
         VALUE obj = RARRAY_AREF(body, i);
 
-	if (SYMBOL_P(obj)) {
-	    rb_event_flag_t event;
-	    if ((event = event_name_to_flag(obj)) != RUBY_EVENT_NONE) {
-		ADD_TRACE(anchor, event);
-	    }
-	    else {
-		LABEL *label = register_label(iseq, labels_table, obj);
-		ADD_LABEL(anchor, label);
-	    }
-	}
-	else if (FIXNUM_P(obj)) {
-	    line_no = NUM2INT(obj);
-	}
-	else if (RB_TYPE_P(obj, T_ARRAY)) {
-	    VALUE *argv = 0;
-	    int argc = RARRAY_LENINT(obj) - 1;
-	    st_data_t insn_id;
-	    VALUE insn;
+        if (SYMBOL_P(obj)) {
+            rb_event_flag_t event;
+            if ((event = event_name_to_flag(obj)) != RUBY_EVENT_NONE) {
+                ADD_TRACE(anchor, event);
+            }
+            else {
+                LABEL *label = register_label(iseq, labels_table, obj);
+                ADD_LABEL(anchor, label);
+            }
+        }
+        else if (FIXNUM_P(obj)) {
+            line_no = NUM2INT(obj);
+        }
+        else if (RB_TYPE_P(obj, T_ARRAY)) {
+            VALUE *argv = 0;
+            int argc = RARRAY_LENINT(obj) - 1;
+            st_data_t insn_id;
+            VALUE insn;
 
             if (node_ids) {
                 node_id = NUM2INT(rb_ary_entry(node_ids, insn_idx++));
             }
 
-	    insn = (argc < 0) ? Qnil : RARRAY_AREF(obj, 0);
-	    if (st_lookup(insn_table, (st_data_t)insn, &insn_id) == 0) {
-		/* TODO: exception */
-		COMPILE_ERROR(iseq, line_no,
-			      "unknown instruction: %+"PRIsVALUE, insn);
-		ret = COMPILE_NG;
-		break;
-	    }
+            insn = (argc < 0) ? Qnil : RARRAY_AREF(obj, 0);
+            if (st_lookup(insn_table, (st_data_t)insn, &insn_id) == 0) {
+                /* TODO: exception */
+                COMPILE_ERROR(iseq, line_no,
+                              "unknown instruction: %+"PRIsVALUE, insn);
+                ret = COMPILE_NG;
+                break;
+            }
 
-	    if (argc != insn_len((VALUE)insn_id)-1) {
-		COMPILE_ERROR(iseq, line_no,
-			      "operand size mismatch");
-		ret = COMPILE_NG;
-		break;
-	    }
+            if (argc != insn_len((VALUE)insn_id)-1) {
+                COMPILE_ERROR(iseq, line_no,
+                              "operand size mismatch");
+                ret = COMPILE_NG;
+                break;
+            }
 
-	    if (argc > 0) {
+            if (argc > 0) {
                 argv = compile_data_calloc2(iseq, sizeof(VALUE), argc);
 
                 // add element before operand setup to make GC root
@@ -10261,95 +10580,120 @@ iseq_build_from_ary_body(rb_iseq_t *iseq, LINK_ANCHOR *const anchor,
                          (LINK_ELEMENT*)new_insn_core(iseq, &dummy_line_node,
                                                       (enum ruby_vminsn_type)insn_id, argc, argv));
 
-		for (j=0; j<argc; j++) {
-		    VALUE op = rb_ary_entry(obj, j+1);
-		    switch (insn_op_type((VALUE)insn_id, j)) {
-		      case TS_OFFSET: {
-			LABEL *label = register_label(iseq, labels_table, op);
-			argv[j] = (VALUE)label;
-			break;
-		      }
-		      case TS_LINDEX:
-		      case TS_NUM:
-			(void)NUM2INT(op);
-			argv[j] = op;
-			break;
-		      case TS_VALUE:
-			argv[j] = op;
-			RB_OBJ_WRITTEN(iseq, Qundef, op);
-			break;
-		      case TS_ISEQ:
-			{
-			    if (op != Qnil) {
-				VALUE v = (VALUE)iseq_build_load_iseq(iseq, op);
-				argv[j] = v;
-				RB_OBJ_WRITTEN(iseq, Qundef, v);
-			    }
-			    else {
-				argv[j] = 0;
-			    }
-			}
-			break;
-		      case TS_ISE:
-		      case TS_IC:
+                for (j=0; j<argc; j++) {
+                    VALUE op = rb_ary_entry(obj, j+1);
+                    switch (insn_op_type((VALUE)insn_id, j)) {
+                      case TS_OFFSET: {
+                        LABEL *label = register_label(iseq, labels_table, op);
+                        argv[j] = (VALUE)label;
+                        break;
+                      }
+                      case TS_LINDEX:
+                      case TS_NUM:
+                        (void)NUM2INT(op);
+                        argv[j] = op;
+                        break;
+                      case TS_VALUE:
+                        argv[j] = op;
+                        RB_OBJ_WRITTEN(iseq, Qundef, op);
+                        break;
+                      case TS_ISEQ:
+                        {
+                            if (op != Qnil) {
+                                VALUE v = (VALUE)iseq_build_load_iseq(iseq, op);
+                                argv[j] = v;
+                                RB_OBJ_WRITTEN(iseq, Qundef, v);
+                            }
+                            else {
+                                argv[j] = 0;
+                            }
+                        }
+                        break;
+                      case TS_ISE:
+                        argv[j] = op;
+                        if (NUM2UINT(op) >= ISEQ_BODY(iseq)->ise_size) {
+                            ISEQ_BODY(iseq)->ise_size = NUM2INT(op) + 1;
+                        }
+                        break;
+                      case TS_IC:
+                        {
+                            VALUE segments = rb_ary_new();
+                            op = rb_to_array_type(op);
+
+                            for (int i = 0; i < RARRAY_LEN(op); i++) {
+                                VALUE sym = RARRAY_AREF(op, i);
+                                sym = rb_to_symbol_type(sym);
+                                rb_ary_push(segments, sym);
+                            }
+
+                            RB_GC_GUARD(op);
+                            argv[j] = segments;
+                            RB_OBJ_WRITTEN(iseq, Qundef, segments);
+                            ISEQ_BODY(iseq)->ic_size++;
+                        }
+                        break;
                       case TS_IVC:  /* inline ivar cache */
+                        argv[j] = op;
+                        if (NUM2UINT(op) >= ISEQ_BODY(iseq)->ivc_size) {
+                            ISEQ_BODY(iseq)->ivc_size = NUM2INT(op) + 1;
+                        }
+                        break;
                       case TS_ICVARC:  /* inline cvar cache */
-			argv[j] = op;
-                        if (NUM2UINT(op) >= ISEQ_BODY(iseq)->is_size) {
-                            ISEQ_BODY(iseq)->is_size = NUM2INT(op) + 1;
+                        argv[j] = op;
+                        if (NUM2UINT(op) >= ISEQ_BODY(iseq)->icvarc_size) {
+                            ISEQ_BODY(iseq)->icvarc_size = NUM2INT(op) + 1;
                         }
-                        FL_SET((VALUE)iseq, ISEQ_MARKABLE_ISEQ);
-			break;
+                        break;
                       case TS_CALLDATA:
-			argv[j] = iseq_build_callinfo_from_hash(iseq, op);
-			break;
-		      case TS_ID:
-			argv[j] = rb_to_symbol_type(op);
-			break;
-		      case TS_CDHASH:
-			{
-			    int i;
-			    VALUE map = rb_hash_new_with_size(RARRAY_LEN(op)/2);
+                        argv[j] = iseq_build_callinfo_from_hash(iseq, op);
+                        break;
+                      case TS_ID:
+                        argv[j] = rb_to_symbol_type(op);
+                        break;
+                      case TS_CDHASH:
+                        {
+                            int i;
+                            VALUE map = rb_hash_new_with_size(RARRAY_LEN(op)/2);
 
                             RHASH_TBL_RAW(map)->type = &cdhash_type;
-			    op = rb_to_array_type(op);
-			    for (i=0; i<RARRAY_LEN(op); i+=2) {
-				VALUE key = RARRAY_AREF(op, i);
-				VALUE sym = RARRAY_AREF(op, i+1);
-				LABEL *label =
-				  register_label(iseq, labels_table, sym);
-				rb_hash_aset(map, key, (VALUE)label | 1);
-			    }
-			    RB_GC_GUARD(op);
-			    argv[j] = map;
-			    RB_OBJ_WRITTEN(iseq, Qundef, map);
-			}
-			break;
-		      case TS_FUNCPTR:
-			{
+                            op = rb_to_array_type(op);
+                            for (i=0; i<RARRAY_LEN(op); i+=2) {
+                                VALUE key = RARRAY_AREF(op, i);
+                                VALUE sym = RARRAY_AREF(op, i+1);
+                                LABEL *label =
+                                  register_label(iseq, labels_table, sym);
+                                rb_hash_aset(map, key, (VALUE)label | 1);
+                            }
+                            RB_GC_GUARD(op);
+                            argv[j] = map;
+                            RB_OBJ_WRITTEN(iseq, Qundef, map);
+                        }
+                        break;
+                      case TS_FUNCPTR:
+                        {
 #if SIZEOF_VALUE <= SIZEOF_LONG
-			    long funcptr = NUM2LONG(op);
+                            long funcptr = NUM2LONG(op);
 #else
-			    LONG_LONG funcptr = NUM2LL(op);
+                            LONG_LONG funcptr = NUM2LL(op);
 #endif
-			    argv[j] = (VALUE)funcptr;
-			}
-			break;
-		      default:
-			rb_raise(rb_eSyntaxError, "unknown operand: %c", insn_op_type((VALUE)insn_id, j));
-		    }
-		}
-	    }
+                            argv[j] = (VALUE)funcptr;
+                        }
+                        break;
+                      default:
+                        rb_raise(rb_eSyntaxError, "unknown operand: %c", insn_op_type((VALUE)insn_id, j));
+                    }
+                }
+            }
             else {
                 NODE dummy_line_node = generate_dummy_line_node(line_no, node_id);
                 ADD_ELEM(anchor,
                          (LINK_ELEMENT*)new_insn_core(iseq, &dummy_line_node,
                                                       (enum ruby_vminsn_type)insn_id, argc, NULL));
             }
-	}
-	else {
-	    rb_raise(rb_eTypeError, "unexpected object for instruction");
-	}
+        }
+        else {
+            rb_raise(rb_eTypeError, "unexpected object for instruction");
+        }
     }
     DATA_PTR(labels_wrapper) = 0;
     validate_labels(iseq, labels_table);
@@ -10365,12 +10709,12 @@ int_param(int *dst, VALUE param, VALUE sym)
 {
     VALUE val = rb_hash_aref(param, sym);
     if (FIXNUM_P(val)) {
-	*dst = FIX2INT(val);
-	return TRUE;
+        *dst = FIX2INT(val);
+        return TRUE;
     }
     else if (!NIL_P(val)) {
-	rb_raise(rb_eTypeError, "invalid %+"PRIsVALUE" Fixnum: %+"PRIsVALUE,
-		 sym, val);
+        rb_raise(rb_eTypeError, "invalid %+"PRIsVALUE" Fixnum: %+"PRIsVALUE,
+                 sym, val);
     }
     return FALSE;
 }
@@ -10397,20 +10741,20 @@ iseq_build_kw(rb_iseq_t *iseq, VALUE params, VALUE keywords)
 
     /* required args */
     for (i = 0; i < len; i++) {
-	VALUE val = RARRAY_AREF(keywords, i);
+        VALUE val = RARRAY_AREF(keywords, i);
 
-	if (!SYMBOL_P(val)) {
-	    goto default_values;
-	}
-	ids[i] = SYM2ID(val);
-	keyword->required_num++;
+        if (!SYMBOL_P(val)) {
+            goto default_values;
+        }
+        ids[i] = SYM2ID(val);
+        keyword->required_num++;
     }
 
   default_values: /* note: we intentionally preserve `i' from previous loop */
     default_len = len - i;
     if (default_len == 0) {
-	keyword->table = ids;
-	return keyword;
+        keyword->table = ids;
+        return keyword;
     }
     else if (default_len < 0) {
         UNREACHABLE;
@@ -10419,23 +10763,23 @@ iseq_build_kw(rb_iseq_t *iseq, VALUE params, VALUE keywords)
     dvs = ALLOC_N(VALUE, (unsigned int)default_len);
 
     for (j = 0; i < len; i++, j++) {
-	key = RARRAY_AREF(keywords, i);
-	CHECK_ARRAY(key);
-
-	switch (RARRAY_LEN(key)) {
-	  case 1:
-	    sym = RARRAY_AREF(key, 0);
-	    default_val = Qundef;
-	    break;
-	  case 2:
-	    sym = RARRAY_AREF(key, 0);
-	    default_val = RARRAY_AREF(key, 1);
-	    break;
-	  default:
-	    rb_raise(rb_eTypeError, "keyword default has unsupported len %+"PRIsVALUE, key);
-	}
-	ids[i] = SYM2ID(sym);
-	dvs[j] = default_val;
+        key = RARRAY_AREF(keywords, i);
+        CHECK_ARRAY(key);
+
+        switch (RARRAY_LEN(key)) {
+          case 1:
+            sym = RARRAY_AREF(key, 0);
+            default_val = Qundef;
+            break;
+          case 2:
+            sym = RARRAY_AREF(key, 0);
+            default_val = RARRAY_AREF(key, 1);
+            break;
+          default:
+            rb_raise(rb_eTypeError, "keyword default has unsupported len %+"PRIsVALUE, key);
+        }
+        ids[i] = SYM2ID(sym);
+        dvs[j] = default_val;
     }
 
     keyword->table = ids;
@@ -10444,6 +10788,12 @@ iseq_build_kw(rb_iseq_t *iseq, VALUE params, VALUE keywords)
     return keyword;
 }
 
+static void
+iseq_insn_each_object_mark(VALUE *obj_ptr, VALUE _)
+{
+    rb_gc_mark(*obj_ptr);
+}
+
 void
 rb_iseq_mark_insn_storage(struct iseq_compile_data_storage *storage)
 {
@@ -10470,28 +10820,7 @@ rb_iseq_mark_insn_storage(struct iseq_compile_data_storage *storage)
             iobj = (INSN *)&storage->buff[pos];
 
             if (iobj->operands) {
-                int j;
-                const char *types = insn_op_types(iobj->insn_id);
-
-                for (j = 0; types[j]; j++) {
-                    char type = types[j];
-                    switch (type) {
-                      case TS_CDHASH:
-                      case TS_ISEQ:
-                      case TS_VALUE:
-                      case TS_CALLDATA: // ci is stored.
-                        {
-                            VALUE op = OPERAND_AT(iobj, j);
-
-                            if (!SPECIAL_CONST_P(op)) {
-                                rb_gc_mark(op);
-                            }
-                        }
-                        break;
-                      default:
-                        break;
-                    }
-                }
+                iseq_insn_each_markable_object(iobj, iseq_insn_each_object_mark, (VALUE)0);
             }
             pos += (int)size;
         }
@@ -10500,7 +10829,7 @@ rb_iseq_mark_insn_storage(struct iseq_compile_data_storage *storage)
 
 void
 rb_iseq_build_from_ary(rb_iseq_t *iseq, VALUE misc, VALUE locals, VALUE params,
-			 VALUE exception, VALUE body)
+                         VALUE exception, VALUE body)
 {
 #define SYM(s) ID2SYM(rb_intern_const(#s))
     int i, len;
@@ -10519,14 +10848,14 @@ rb_iseq_build_from_ary(rb_iseq_t *iseq, VALUE misc, VALUE locals, VALUE params,
     ISEQ_BODY(iseq)->local_table = tbl = len > 0 ? (ID *)ALLOC_N(ID, ISEQ_BODY(iseq)->local_table_size) : NULL;
 
     for (i = 0; i < len; i++) {
-	VALUE lv = RARRAY_AREF(locals, i);
+        VALUE lv = RARRAY_AREF(locals, i);
 
-	if (sym_arg_rest == lv) {
-	    tbl[i] = 0;
-	}
-	else {
-	    tbl[i] = FIXNUM_P(lv) ? (ID)FIX2LONG(lv) : SYM2ID(CHECK_SYMBOL(lv));
-	}
+        if (sym_arg_rest == lv) {
+            tbl[i] = 0;
+        }
+        else {
+            tbl[i] = FIXNUM_P(lv) ? (ID)FIX2LONG(lv) : SYM2ID(CHECK_SYMBOL(lv));
+        }
     }
 
 #define INT_PARAM(F) int_param(&ISEQ_BODY(iseq)->param.F, params, SYM(F))
@@ -10540,10 +10869,10 @@ rb_iseq_build_from_ary(rb_iseq_t *iseq, VALUE misc, VALUE locals, VALUE params,
 #undef INT_PARAM
     {
 #define INT_PARAM(F) F = (int_param(&x, misc, SYM(F)) ? (unsigned int)x : 0)
-	int x;
-	INT_PARAM(arg_size);
-	INT_PARAM(local_size);
-	INT_PARAM(stack_max);
+        int x;
+        INT_PARAM(arg_size);
+        INT_PARAM(local_size);
+        INT_PARAM(stack_max);
 #undef INT_PARAM
     }
 
@@ -10551,38 +10880,38 @@ rb_iseq_build_from_ary(rb_iseq_t *iseq, VALUE misc, VALUE locals, VALUE params,
 #ifdef USE_ISEQ_NODE_ID
     node_ids = rb_hash_aref(misc, ID2SYM(rb_intern("node_ids")));
     if (!RB_TYPE_P(node_ids, T_ARRAY)) {
-	rb_raise(rb_eTypeError, "node_ids is not an array");
+        rb_raise(rb_eTypeError, "node_ids is not an array");
     }
 #endif
 
     if (RB_TYPE_P(arg_opt_labels, T_ARRAY)) {
-	len = RARRAY_LENINT(arg_opt_labels);
+        len = RARRAY_LENINT(arg_opt_labels);
         ISEQ_BODY(iseq)->param.flags.has_opt = !!(len - 1 >= 0);
 
         if (ISEQ_BODY(iseq)->param.flags.has_opt) {
-	    VALUE *opt_table = ALLOC_N(VALUE, len);
+            VALUE *opt_table = ALLOC_N(VALUE, len);
 
-	    for (i = 0; i < len; i++) {
-		VALUE ent = RARRAY_AREF(arg_opt_labels, i);
-		LABEL *label = register_label(iseq, labels_table, ent);
-		opt_table[i] = (VALUE)label;
-	    }
+            for (i = 0; i < len; i++) {
+                VALUE ent = RARRAY_AREF(arg_opt_labels, i);
+                LABEL *label = register_label(iseq, labels_table, ent);
+                opt_table[i] = (VALUE)label;
+            }
 
             ISEQ_BODY(iseq)->param.opt_num = len - 1;
             ISEQ_BODY(iseq)->param.opt_table = opt_table;
-	}
+        }
     }
     else if (!NIL_P(arg_opt_labels)) {
-	rb_raise(rb_eTypeError, ":opt param is not an array: %+"PRIsVALUE,
-		 arg_opt_labels);
+        rb_raise(rb_eTypeError, ":opt param is not an array: %+"PRIsVALUE,
+                 arg_opt_labels);
     }
 
     if (RB_TYPE_P(keywords, T_ARRAY)) {
         ISEQ_BODY(iseq)->param.keyword = iseq_build_kw(iseq, params, keywords);
     }
     else if (!NIL_P(keywords)) {
-	rb_raise(rb_eTypeError, ":keywords param is not an array: %+"PRIsVALUE,
-		 keywords);
+        rb_raise(rb_eTypeError, ":keywords param is not an array: %+"PRIsVALUE,
+                 keywords);
     }
 
     if (Qtrue == rb_hash_aref(params, SYM(ambiguous_param0))) {
@@ -10591,10 +10920,10 @@ rb_iseq_build_from_ary(rb_iseq_t *iseq, VALUE misc, VALUE locals, VALUE params,
 
     if (int_param(&i, params, SYM(kwrest))) {
         struct rb_iseq_param_keyword *keyword = (struct rb_iseq_param_keyword *)ISEQ_BODY(iseq)->param.keyword;
-	if (keyword == NULL) {
+        if (keyword == NULL) {
             ISEQ_BODY(iseq)->param.keyword = keyword = ZALLOC(struct rb_iseq_param_keyword);
-	}
-	keyword->rest_start = i;
+        }
+        keyword->rest_start = i;
         ISEQ_BODY(iseq)->param.flags.has_kwrest = TRUE;
     }
 #undef SYM
@@ -10618,22 +10947,22 @@ rb_dvar_defined(ID id, const rb_iseq_t *iseq)
 {
     if (iseq) {
         const struct rb_iseq_constant_body *body = ISEQ_BODY(iseq);
-	while (body->type == ISEQ_TYPE_BLOCK ||
-	       body->type == ISEQ_TYPE_RESCUE ||
-	       body->type == ISEQ_TYPE_ENSURE ||
-	       body->type == ISEQ_TYPE_EVAL ||
-	       body->type == ISEQ_TYPE_MAIN
-	       ) {
-	    unsigned int i;
-
-	    for (i = 0; i < body->local_table_size; i++) {
-		if (body->local_table[i] == id) {
-		    return 1;
-		}
-	    }
-	    iseq = body->parent_iseq;
+        while (body->type == ISEQ_TYPE_BLOCK ||
+               body->type == ISEQ_TYPE_RESCUE ||
+               body->type == ISEQ_TYPE_ENSURE ||
+               body->type == ISEQ_TYPE_EVAL ||
+               body->type == ISEQ_TYPE_MAIN
+               ) {
+            unsigned int i;
+
+            for (i = 0; i < body->local_table_size; i++) {
+                if (body->local_table[i] == id) {
+                    return 1;
+                }
+            }
+            iseq = body->parent_iseq;
             body = ISEQ_BODY(iseq);
-	}
+        }
     }
     return 0;
 }
@@ -10642,14 +10971,14 @@ int
 rb_local_defined(ID id, const rb_iseq_t *iseq)
 {
     if (iseq) {
-	unsigned int i;
+        unsigned int i;
         const struct rb_iseq_constant_body *const body = ISEQ_BODY(ISEQ_BODY(iseq)->local_iseq);
 
-	for (i=0; i<body->local_table_size; i++) {
-	    if (body->local_table[i] == id) {
-		return 1;
-	    }
-	}
+        for (i=0; i<body->local_table_size; i++) {
+            if (body->local_table[i] == id) {
+                return 1;
+            }
+        }
     }
     return 0;
 }
@@ -10668,8 +10997,8 @@ typedef unsigned int ibf_offset_t;
 #define IBF_OFFSET(ptr) ((ibf_offset_t)(VALUE)(ptr))
 
 #define IBF_MAJOR_VERSION ISEQ_MAJOR_VERSION
-#if RUBY_DEVEL
-#define IBF_DEVEL_VERSION 3
+#ifdef RUBY_DEVEL
+#define IBF_DEVEL_VERSION 4
 #define IBF_MINOR_VERSION (ISEQ_MINOR_VERSION * 10000 + IBF_DEVEL_VERSION)
 #else
 #define IBF_MINOR_VERSION ISEQ_MINOR_VERSION
@@ -10699,8 +11028,6 @@ struct ibf_dump {
     struct ibf_dump_buffer *current_buffer;
 };
 
-rb_iseq_t * iseq_alloc(void);
-
 struct ibf_load_buffer {
     const char *buff;
     ibf_offset_t size;
@@ -11109,17 +11436,18 @@ ibf_dump_code(struct ibf_dump *dump, const rb_iseq_t *iseq)
                 wv = (VALUE)ibf_dump_iseq(dump, (const rb_iseq_t *)op);
                 break;
               case TS_IC:
+                {
+                    IC ic = (IC)op;
+                    VALUE arr = idlist_to_array(ic->segments);
+                    wv = ibf_dump_object(dump, arr);
+                }
+                break;
+              case TS_ISE:
               case TS_IVC:
               case TS_ICVARC:
-              case TS_ISE:
                 {
-                    unsigned int i;
-                    for (i=0; i<body->is_size; i++) {
-                        if (op == (VALUE)&body->is_entries[i]) {
-                            break;
-                        }
-                    }
-                    wv = (VALUE)i;
+                    union iseq_inline_storage_entry *is = (union iseq_inline_storage_entry *)op;
+                    wv = is - ISEQ_IS_ENTRY_START(body, types[op_index]);
                 }
                 break;
               case TS_CALLDATA:
@@ -11158,12 +11486,23 @@ ibf_load_code(const struct ibf_load *load, rb_iseq_t *iseq, ibf_offset_t bytecod
 
     struct rb_iseq_constant_body *load_body = ISEQ_BODY(iseq);
     struct rb_call_data *cd_entries = load_body->call_data;
-    union iseq_inline_storage_entry *is_entries = load_body->is_entries;
+    int ic_index = 0;
+
+    iseq_bits_t * mark_offset_bits;
+
+    iseq_bits_t tmp[1] = {0};
+
+    if (ISEQ_MBITS_BUFLEN(iseq_size) == 1) {
+        mark_offset_bits = tmp;
+    }
+    else {
+        mark_offset_bits = ZALLOC_N(iseq_bits_t, ISEQ_MBITS_BUFLEN(iseq_size));
+    }
+    bool needs_bitmap = false;
 
     for (code_index=0; code_index<iseq_size;) {
         /* opcode */
         const VALUE insn = code[code_index] = ibf_load_small_value(load, &reading_pos);
-        const unsigned int insn_index = code_index;
         const char *types = insn_op_types(insn);
         int op_index;
 
@@ -11180,7 +11519,8 @@ ibf_load_code(const struct ibf_load *load, rb_iseq_t *iseq, ibf_offset_t bytecod
                     code[code_index] = v;
                     if (!SPECIAL_CONST_P(v)) {
                         RB_OBJ_WRITTEN(iseqv, Qundef, v);
-                        FL_SET(iseqv, ISEQ_MARKABLE_ISEQ);
+                        ISEQ_MBITS_SET(mark_offset_bits, code_index);
+                        needs_bitmap = true;
                     }
                     break;
                 }
@@ -11199,8 +11539,9 @@ ibf_load_code(const struct ibf_load *load, rb_iseq_t *iseq, ibf_offset_t bytecod
                     pinned_list_store(load->current_buffer->obj_list, (long)op, v);
 
                     code[code_index] = v;
+                    ISEQ_MBITS_SET(mark_offset_bits, code_index);
                     RB_OBJ_WRITTEN(iseqv, Qundef, v);
-                    FL_SET(iseqv, ISEQ_MARKABLE_ISEQ);
+                    needs_bitmap = true;
                     break;
                 }
               case TS_ISEQ:
@@ -11210,25 +11551,46 @@ ibf_load_code(const struct ibf_load *load, rb_iseq_t *iseq, ibf_offset_t bytecod
                     code[code_index] = v;
                     if (!SPECIAL_CONST_P(v)) {
                         RB_OBJ_WRITTEN(iseqv, Qundef, v);
-                        FL_SET(iseqv, ISEQ_MARKABLE_ISEQ);
+                        ISEQ_MBITS_SET(mark_offset_bits, code_index);
+                        needs_bitmap = true;
                     }
                     break;
                 }
-              case TS_ISE:
               case TS_IC:
-              case TS_IVC:
-              case TS_ICVARC:
                 {
                     VALUE op = ibf_load_small_value(load, &reading_pos);
-                    code[code_index] = (VALUE)&is_entries[op];
+                    VALUE arr = ibf_load_object(load, op);
+
+                    IC ic = &ISEQ_IS_IC_ENTRY(load_body, ic_index++);
+                    ic->segments = array_to_idlist(arr);
+
+                    code[code_index] = (VALUE)ic;
+                }
+                break;
+              case TS_ISE:
+              case TS_ICVARC:
+              case TS_IVC:
+                {
+                    unsigned int op = (unsigned int)ibf_load_small_value(load, &reading_pos);
+
+                    ISE ic = ISEQ_IS_ENTRY_START(load_body, operand_type) + op;
+                    code[code_index] = (VALUE)ic;
+
+                    if (operand_type == TS_IVC) {
+                        IVC cache = (IVC)ic;
 
-                    if (insn == BIN(opt_getinlinecache) && operand_type == TS_IC) {
-                        // Store the instruction index for opt_getinlinecache on the IC for
-                        // YJIT to invalidate code when opt_setinlinecache runs.
-                        is_entries[op].ic_cache.get_insn_idx = insn_index;
+                        if (insn == BIN(setinstancevariable)) {
+                            ID iv_name = (ID)code[code_index - 1];
+                            cache->iv_set_name = iv_name;
+                        }
+                        else {
+                            cache->iv_set_name = 0;
+                        }
+
+                        vm_ic_attr_index_initialize(cache, INVALID_SHAPE_ID);
                     }
+
                 }
-                FL_SET(iseqv, ISEQ_MARKABLE_ISEQ);
                 break;
               case TS_CALLDATA:
                 {
@@ -11256,9 +11618,23 @@ ibf_load_code(const struct ibf_load *load, rb_iseq_t *iseq, ibf_offset_t bytecod
             rb_raise(rb_eRuntimeError, "operand size mismatch");
         }
     }
+
     load_body->iseq_encoded = code;
     load_body->iseq_size = code_index;
 
+    if (ISEQ_MBITS_BUFLEN(load_body->iseq_size) == 1) {
+        load_body->mark_bits.single = mark_offset_bits[0];
+    }
+    else {
+        if (needs_bitmap) {
+            load_body->mark_bits.list = mark_offset_bits;
+        }
+        else {
+            load_body->mark_bits.list = 0;
+            ruby_xfree(mark_offset_bits);
+        }
+    }
+
     assert(code_index == iseq_size);
     assert(reading_pos == bytecode_offset + bytecode_size);
     return code;
@@ -11484,7 +11860,7 @@ ibf_load_catch_table(const struct ibf_load *load, ibf_offset_t catch_table_offse
         unsigned int i;
         for (i=0; i<table->size; i++) {
             int iseq_index = (int)ibf_load_small_value(load, &reading_pos);
-            table->entries[i].type = (enum catch_type)ibf_load_small_value(load, &reading_pos);
+            table->entries[i].type = (enum rb_catch_type)ibf_load_small_value(load, &reading_pos);
             table->entries[i].start = (unsigned int)ibf_load_small_value(load, &reading_pos);
             table->entries[i].end = (unsigned int)ibf_load_small_value(load, &reading_pos);
             table->entries[i].cont = (unsigned int)ibf_load_small_value(load, &reading_pos);
@@ -11739,7 +12115,10 @@ ibf_dump_iseq_each(struct ibf_dump *dump, const rb_iseq_t *iseq)
     ibf_dump_write_small_value(dump, IBF_BODY_OFFSET(outer_variables_offset));
     ibf_dump_write_small_value(dump, body->variable.flip_count);
     ibf_dump_write_small_value(dump, body->local_table_size);
-    ibf_dump_write_small_value(dump, body->is_size);
+    ibf_dump_write_small_value(dump, body->ivc_size);
+    ibf_dump_write_small_value(dump, body->icvarc_size);
+    ibf_dump_write_small_value(dump, body->ise_size);
+    ibf_dump_write_small_value(dump, body->ic_size);
     ibf_dump_write_small_value(dump, body->ci_size);
     ibf_dump_write_small_value(dump, body->stack_max);
     ibf_dump_write_small_value(dump, body->catch_except_p);
@@ -11828,7 +12207,7 @@ ibf_load_iseq_each(struct ibf_load *load, rb_iseq_t *iseq, ibf_offset_t offset)
     const VALUE location_pathobj_index = ibf_load_small_value(load, &reading_pos);
     const VALUE location_base_label_index = ibf_load_small_value(load, &reading_pos);
     const VALUE location_label_index = ibf_load_small_value(load, &reading_pos);
-    const VALUE location_first_lineno = ibf_load_small_value(load, &reading_pos);
+    const int location_first_lineno = (int)ibf_load_small_value(load, &reading_pos);
     const int location_node_id = (int)ibf_load_small_value(load, &reading_pos);
     const int location_code_location_beg_pos_lineno = (int)ibf_load_small_value(load, &reading_pos);
     const int location_code_location_beg_pos_column = (int)ibf_load_small_value(load, &reading_pos);
@@ -11847,12 +12226,51 @@ ibf_load_iseq_each(struct ibf_load *load, rb_iseq_t *iseq, ibf_offset_t offset)
     const ibf_offset_t outer_variables_offset = (ibf_offset_t)IBF_BODY_OFFSET(ibf_load_small_value(load, &reading_pos));
     const rb_snum_t variable_flip_count = (rb_snum_t)ibf_load_small_value(load, &reading_pos);
     const unsigned int local_table_size = (unsigned int)ibf_load_small_value(load, &reading_pos);
-    const unsigned int is_size = (unsigned int)ibf_load_small_value(load, &reading_pos);
+
+    const unsigned int ivc_size = (unsigned int)ibf_load_small_value(load, &reading_pos);
+    const unsigned int icvarc_size = (unsigned int)ibf_load_small_value(load, &reading_pos);
+    const unsigned int ise_size = (unsigned int)ibf_load_small_value(load, &reading_pos);
+    const unsigned int ic_size = (unsigned int)ibf_load_small_value(load, &reading_pos);
+
     const unsigned int ci_size = (unsigned int)ibf_load_small_value(load, &reading_pos);
     const unsigned int stack_max = (unsigned int)ibf_load_small_value(load, &reading_pos);
     const char catch_except_p = (char)ibf_load_small_value(load, &reading_pos);
     const bool builtin_inline_p = (bool)ibf_load_small_value(load, &reading_pos);
 
+    // setup fname and dummy frame
+    VALUE path = ibf_load_object(load, location_pathobj_index);
+    {
+        VALUE realpath = Qnil;
+
+        if (RB_TYPE_P(path, T_STRING)) {
+            realpath = path = rb_fstring(path);
+        }
+        else if (RB_TYPE_P(path, T_ARRAY)) {
+            VALUE pathobj = path;
+            if (RARRAY_LEN(pathobj) != 2) {
+                rb_raise(rb_eRuntimeError, "path object size mismatch");
+            }
+            path = rb_fstring(RARRAY_AREF(pathobj, 0));
+            realpath = RARRAY_AREF(pathobj, 1);
+            if (!NIL_P(realpath)) {
+                if (!RB_TYPE_P(realpath, T_STRING)) {
+                    rb_raise(rb_eArgError, "unexpected realpath %"PRIxVALUE
+                             "(%x), path=%+"PRIsVALUE,
+                             realpath, TYPE(realpath), path);
+                }
+                realpath = rb_fstring(realpath);
+            }
+        }
+        else {
+            rb_raise(rb_eRuntimeError, "unexpected path object");
+        }
+        rb_iseq_pathobj_set(iseq, path, realpath);
+    }
+
+    // push dummy frame
+    rb_execution_context_t *ec = GET_EC();
+    VALUE dummy_frame = rb_vm_push_frame_fname(ec, path);
+
 #undef IBF_BODY_OFFSET
 
     load_body->type = type;
@@ -11875,7 +12293,6 @@ ibf_load_iseq_each(struct ibf_load *load, rb_iseq_t *iseq, ibf_offset_t offset)
     load_body->param.post_num = param_post_num;
     load_body->param.block_start = param_block_start;
     load_body->local_table_size = local_table_size;
-    load_body->is_size = is_size;
     load_body->ci_size = ci_size;
     load_body->insns_info.size = insns_info_size;
 
@@ -11893,7 +12310,11 @@ ibf_load_iseq_each(struct ibf_load *load, rb_iseq_t *iseq, ibf_offset_t offset)
     load_body->catch_except_p = catch_except_p;
     load_body->builtin_inline_p = builtin_inline_p;
 
-    load_body->is_entries           = ZALLOC_N(union iseq_inline_storage_entry, is_size);
+    load_body->ivc_size             = ivc_size;
+    load_body->icvarc_size          = icvarc_size;
+    load_body->ise_size             = ise_size;
+    load_body->ic_size              = ic_size;
+    load_body->is_entries           = ZALLOC_N(union iseq_inline_storage_entry, ISEQ_IS_SIZE(load_body));
                                       ibf_load_ci_entries(load, ci_entries_offset, ci_size, &load_body->call_data);
     load_body->outer_variables      = ibf_load_outer_variables(load, outer_variables_offset);
     load_body->param.opt_table      = ibf_load_param_opt_table(load, param_opt_table_offset, param_opt_num);
@@ -11918,33 +12339,6 @@ ibf_load_iseq_each(struct ibf_load *load, rb_iseq_t *iseq, ibf_offset_t offset)
     load->current_buffer = &load->global_buffer;
 #endif
 
-    {
-        VALUE realpath = Qnil, path = ibf_load_object(load, location_pathobj_index);
-        if (RB_TYPE_P(path, T_STRING)) {
-            realpath = path = rb_fstring(path);
-        }
-        else if (RB_TYPE_P(path, T_ARRAY)) {
-            VALUE pathobj = path;
-            if (RARRAY_LEN(pathobj) != 2) {
-                rb_raise(rb_eRuntimeError, "path object size mismatch");
-            }
-            path = rb_fstring(RARRAY_AREF(pathobj, 0));
-            realpath = RARRAY_AREF(pathobj, 1);
-            if (!NIL_P(realpath)) {
-                if (!RB_TYPE_P(realpath, T_STRING)) {
-                    rb_raise(rb_eArgError, "unexpected realpath %"PRIxVALUE
-                             "(%x), path=%+"PRIsVALUE,
-                             realpath, TYPE(realpath), path);
-                }
-                realpath = rb_fstring(realpath);
-            }
-        }
-        else {
-            rb_raise(rb_eRuntimeError, "unexpected path object");
-        }
-        rb_iseq_pathobj_set(iseq, path, realpath);
-    }
-
     RB_OBJ_WRITE(iseq, &load_body->location.base_label,    ibf_load_location_str(load, location_base_label_index));
     RB_OBJ_WRITE(iseq, &load_body->location.label,         ibf_load_location_str(load, location_label_index));
 
@@ -11952,6 +12346,9 @@ ibf_load_iseq_each(struct ibf_load *load, rb_iseq_t *iseq, ibf_offset_t offset)
     load->current_buffer = saved_buffer;
 #endif
     verify_call_cache(iseq);
+
+    RB_GC_GUARD(dummy_frame);
+    rb_vm_pop_frame_no_int(ec);
 }
 
 struct ibf_dump_iseq_list_arg
@@ -11975,7 +12372,7 @@ ibf_dump_iseq_list_i(st_data_t key, st_data_t val, st_data_t ptr)
 static void
 ibf_dump_iseq_list(struct ibf_dump *dump, struct ibf_header *header)
 {
-    VALUE offset_list = rb_ary_tmp_new(dump->iseq_table->num_entries);
+    VALUE offset_list = rb_ary_hidden_new(dump->iseq_table->num_entries);
 
     struct ibf_dump_iseq_list_arg args;
     args.dump = dump;
@@ -12064,7 +12461,7 @@ static const void *
 ibf_load_check_offset(const struct ibf_load *load, size_t offset)
 {
     if (offset >= load->current_buffer->size) {
-	rb_raise(rb_eIndexError, "object offset out of range: %"PRIdSIZE, offset);
+        rb_raise(rb_eIndexError, "object offset out of range: %"PRIdSIZE, offset);
     }
     return load->current_buffer->buff + offset;
 }
@@ -12125,11 +12522,11 @@ ibf_load_object_class(const struct ibf_load *load, const struct ibf_object_heade
 
     switch (cindex) {
       case IBF_OBJECT_CLASS_OBJECT:
-	return rb_cObject;
+        return rb_cObject;
       case IBF_OBJECT_CLASS_ARRAY:
-	return rb_cArray;
+        return rb_cArray;
       case IBF_OBJECT_CLASS_STANDARD_ERROR:
-	return rb_eStandardError;
+        return rb_eStandardError;
       case IBF_OBJECT_CLASS_NO_MATCHING_PATTERN_ERROR:
         return rb_eNoMatchingPatternError;
       case IBF_OBJECT_CLASS_TYPE_ERROR:
@@ -12247,7 +12644,7 @@ ibf_load_object_array(const struct ibf_load *load, const struct ibf_object_heade
 
     const long len = (long)ibf_load_small_value(load, &reading_pos);
 
-    VALUE ary = rb_ary_new_capa(len);
+    VALUE ary = header->internal ? rb_ary_hidden_new(len) : rb_ary_new_capa(len);
     int i;
 
     for (i=0; i<len; i++) {
@@ -12255,8 +12652,7 @@ ibf_load_object_array(const struct ibf_load *load, const struct ibf_object_heade
         rb_ary_push(ary, ibf_load_object(load, index));
     }
 
-    if (header->internal) rb_obj_hide(ary);
-    if (header->frozen)   rb_obj_freeze(ary);
+    if (header->frozen) rb_obj_freeze(ary);
 
     return ary;
 }
@@ -12359,7 +12755,7 @@ ibf_load_object_bignum(const struct ibf_load *load, const struct ibf_object_head
     int sign = bignum->slen > 0;
     ssize_t len = sign > 0 ? bignum->slen : -1 * bignum->slen;
     VALUE obj = rb_integer_unpack(bignum->digits, len * 2, 2, 0,
-				  INTEGER_PACK_LITTLE_ENDIAN | (sign == 0 ? INTEGER_PACK_NEGATIVE : 0));
+                                  INTEGER_PACK_LITTLE_ENDIAN | (sign == 0 ? INTEGER_PACK_NEGATIVE : 0));
     if (header->internal) rb_obj_hide(obj);
     if (header->frozen)   rb_obj_freeze(obj);
     return obj;
@@ -12643,7 +13039,7 @@ static void
 ibf_dump_object_list(struct ibf_dump *dump, ibf_offset_t *obj_list_offset, unsigned int *obj_list_size)
 {
     st_table *obj_table = dump->current_buffer->obj_table;
-    VALUE offset_list = rb_ary_tmp_new(obj_table->num_entries);
+    VALUE offset_list = rb_ary_hidden_new(obj_table->num_entries);
 
     struct ibf_dump_object_list_arg args;
     args.dump = dump;
@@ -12703,7 +13099,7 @@ ibf_dump_memsize(const void *ptr)
 static const rb_data_type_t ibf_dump_type = {
     "ibf_dump",
     {ibf_dump_mark, ibf_dump_free, ibf_dump_memsize,},
-    0, 0, RUBY_TYPED_WB_PROTECTED | RUBY_TYPED_FREE_IMMEDIATELY
+    0, 0, RUBY_TYPED_FREE_IMMEDIATELY
 };
 
 static void
@@ -12786,8 +13182,8 @@ rb_ibf_load_iseq_complete(rb_iseq_t *iseq)
     load->iseq = iseq;
 #if IBF_ISEQ_DEBUG
     fprintf(stderr, "rb_ibf_load_iseq_complete: index=%#x offset=%#x size=%#x\n",
-	    iseq->aux.loader.index, offset,
-	    load->header->size);
+            iseq->aux.loader.index, offset,
+            load->header->size);
 #endif
     ibf_load_iseq_each(load, iseq, offset);
     ISEQ_COMPILE_DATA_CLEAR(iseq);
@@ -12812,37 +13208,37 @@ ibf_load_iseq(const struct ibf_load *load, const rb_iseq_t *index_iseq)
 
 #if IBF_ISEQ_DEBUG
     fprintf(stderr, "ibf_load_iseq: index_iseq=%p iseq_list=%p\n",
-	    (void *)index_iseq, (void *)load->iseq_list);
+            (void *)index_iseq, (void *)load->iseq_list);
 #endif
     if (iseq_index == -1) {
-	return NULL;
+        return NULL;
     }
     else {
-	VALUE iseqv = pinned_list_fetch(load->iseq_list, iseq_index);
+        VALUE iseqv = pinned_list_fetch(load->iseq_list, iseq_index);
 
 #if IBF_ISEQ_DEBUG
-	fprintf(stderr, "ibf_load_iseq: iseqv=%p\n", (void *)iseqv);
+        fprintf(stderr, "ibf_load_iseq: iseqv=%p\n", (void *)iseqv);
 #endif
-	if (iseqv) {
-	    return (rb_iseq_t *)iseqv;
-	}
-	else {
-	    rb_iseq_t *iseq = iseq_imemo_alloc();
+        if (iseqv) {
+            return (rb_iseq_t *)iseqv;
+        }
+        else {
+            rb_iseq_t *iseq = iseq_imemo_alloc();
 #if IBF_ISEQ_DEBUG
-	    fprintf(stderr, "ibf_load_iseq: new iseq=%p\n", (void *)iseq);
+            fprintf(stderr, "ibf_load_iseq: new iseq=%p\n", (void *)iseq);
 #endif
-	    FL_SET((VALUE)iseq, ISEQ_NOT_LOADED_YET);
-	    iseq->aux.loader.obj = load->loader_obj;
-	    iseq->aux.loader.index = iseq_index;
+            FL_SET((VALUE)iseq, ISEQ_NOT_LOADED_YET);
+            iseq->aux.loader.obj = load->loader_obj;
+            iseq->aux.loader.index = iseq_index;
 #if IBF_ISEQ_DEBUG
-	    fprintf(stderr, "ibf_load_iseq: iseq=%p loader_obj=%p index=%d\n",
-		    (void *)iseq, (void *)load->loader_obj, iseq_index);
+            fprintf(stderr, "ibf_load_iseq: iseq=%p loader_obj=%p index=%d\n",
+                    (void *)iseq, (void *)load->loader_obj, iseq_index);
 #endif
-	    pinned_list_store(load->iseq_list, iseq_index, (VALUE)iseq);
+            pinned_list_store(load->iseq_list, iseq_index, (VALUE)iseq);
 
 #if !USE_LAZY_LOAD
 #if IBF_ISEQ_DEBUG
-	    fprintf(stderr, "ibf_load_iseq: loading iseq=%p\n", (void *)iseq);
+            fprintf(stderr, "ibf_load_iseq: loading iseq=%p\n", (void *)iseq);
 #endif
             rb_ibf_load_iseq_complete(iseq);
 #else
@@ -12852,11 +13248,11 @@ ibf_load_iseq(const struct ibf_load *load, const rb_iseq_t *index_iseq)
 #endif /* !USE_LAZY_LOAD */
 
 #if IBF_ISEQ_DEBUG
-	    fprintf(stderr, "ibf_load_iseq: iseq=%p loaded %p\n",
-		    (void *)iseq, (void *)load->iseq);
+            fprintf(stderr, "ibf_load_iseq: iseq=%p loaded %p\n",
+                    (void *)iseq, (void *)load->iseq);
 #endif
-	    return iseq;
-	}
+            return iseq;
+        }
     }
 }
 
@@ -12876,18 +13272,18 @@ ibf_load_setup_bytes(struct ibf_load *load, VALUE loader_obj, const char *bytes,
     load->current_buffer = &load->global_buffer;
 
     if (size < load->header->size) {
-	rb_raise(rb_eRuntimeError, "broken binary format");
+        rb_raise(rb_eRuntimeError, "broken binary format");
     }
     if (strncmp(load->header->magic, "YARB", 4) != 0) {
-	rb_raise(rb_eRuntimeError, "unknown binary format");
+        rb_raise(rb_eRuntimeError, "unknown binary format");
     }
     if (load->header->major_version != IBF_MAJOR_VERSION ||
-	load->header->minor_version != IBF_MINOR_VERSION) {
-	rb_raise(rb_eRuntimeError, "unmatched version file (%u.%u for %u.%u)",
-		 load->header->major_version, load->header->minor_version, IBF_MAJOR_VERSION, IBF_MINOR_VERSION);
+        load->header->minor_version != IBF_MINOR_VERSION) {
+        rb_raise(rb_eRuntimeError, "unmatched version file (%u.%u for %u.%u)",
+                 load->header->major_version, load->header->minor_version, IBF_MAJOR_VERSION, IBF_MINOR_VERSION);
     }
     if (strcmp(load->global_buffer.buff + sizeof(struct ibf_header), RUBY_PLATFORM) != 0) {
-	rb_raise(rb_eRuntimeError, "unmatched platform");
+        rb_raise(rb_eRuntimeError, "unmatched platform");
     }
     if (load->header->iseq_list_offset % RUBY_ALIGNOF(ibf_offset_t)) {
         rb_raise(rb_eArgError, "unaligned iseq list offset: %u",
diff --git a/complex.c b/complex.c
index 92f4e812d6..a227cb0a58 100644
--- a/complex.c
+++ b/complex.c
@@ -97,7 +97,7 @@ inline static VALUE
 f_div(VALUE x, VALUE y)
 {
     if (FIXNUM_P(y) && FIX2LONG(y) == 1)
-	return x;
+        return x;
     return rb_funcall(x, '/', 1, y);
 }
 
@@ -152,7 +152,7 @@ f_sub(VALUE x, VALUE y)
 {
     if (FIXNUM_ZERO_P(y) &&
         LIKELY(rb_method_basic_definition_p(CLASS_OF(x), idMINUS))) {
-	return x;
+        return x;
     }
     return rb_funcall(x, '-', 1, y);
 }
@@ -262,7 +262,7 @@ inline static VALUE
 f_to_i(VALUE x)
 {
     if (RB_TYPE_P(x, T_STRING))
-	return rb_str_to_inum(x, 10, 0);
+        return rb_str_to_inum(x, 10, 0);
     return rb_funcall(x, id_to_i, 0);
 }
 
@@ -270,7 +270,7 @@ inline static VALUE
 f_to_f(VALUE x)
 {
     if (RB_TYPE_P(x, T_STRING))
-	return DBL2NUM(rb_str_to_dbl(x, 0));
+        return DBL2NUM(rb_str_to_dbl(x, 0));
     return rb_funcall(x, id_to_f, 0);
 }
 
@@ -280,9 +280,9 @@ inline static int
 f_eqeq_p(VALUE x, VALUE y)
 {
     if (FIXNUM_P(x) && FIXNUM_P(y))
-	return x == y;
+        return x == y;
     else if (RB_FLOAT_TYPE_P(x) || RB_FLOAT_TYPE_P(y))
-	return NUM2DBL(x) == NUM2DBL(y);
+        return NUM2DBL(x) == NUM2DBL(y);
     return (int)rb_equal(x, y);
 }
 
@@ -316,7 +316,7 @@ f_negative_p(VALUE x)
 
 #define f_positive_p(x) (!f_negative_p(x))
 
-inline static int
+inline static bool
 f_zero_p(VALUE x)
 {
     if (RB_FLOAT_TYPE_P(x)) {
@@ -329,7 +329,7 @@ f_zero_p(VALUE x)
         const VALUE num = RRATIONAL(x)->num;
         return FIXNUM_ZERO_P(num);
     }
-    return (int)rb_equal(x, ZERO);
+    return rb_equal(x, ZERO) != 0;
 }
 
 #define f_nonzero_p(x) (!f_zero_p(x))
@@ -349,7 +349,7 @@ f_finite_p(VALUE x)
         return TRUE;
     }
     else if (RB_FLOAT_TYPE_P(x)) {
-	return isfinite(RFLOAT_VALUE(x));
+        return isfinite(RFLOAT_VALUE(x));
     }
     return RTEST(rb_funcallv(x, id_finite_p, 0, 0));
 }
@@ -361,7 +361,7 @@ f_infinite_p(VALUE x)
         return FALSE;
     }
     else if (RB_FLOAT_TYPE_P(x)) {
-	return isinf(RFLOAT_VALUE(x));
+        return isinf(RFLOAT_VALUE(x));
     }
     return RTEST(rb_funcallv(x, id_infinite_p, 0, 0));
 }
@@ -421,15 +421,22 @@ f_complex_new_bang2(VALUE klass, VALUE x, VALUE y)
     return nucomp_s_new_internal(klass, x, y);
 }
 
-inline static void
+WARN_UNUSED_RESULT(inline static VALUE nucomp_real_check(VALUE num));
+inline static VALUE
 nucomp_real_check(VALUE num)
 {
     if (!RB_INTEGER_TYPE_P(num) &&
-	!RB_FLOAT_TYPE_P(num) &&
-	!RB_TYPE_P(num, T_RATIONAL)) {
-	if (!k_numeric_p(num) || !f_real_p(num))
-	    rb_raise(rb_eTypeError, "not a real");
+        !RB_FLOAT_TYPE_P(num) &&
+        !RB_TYPE_P(num, T_RATIONAL)) {
+        if (RB_TYPE_P(num, T_COMPLEX) && nucomp_real_p(num)) {
+            VALUE real = RCOMPLEX(num)->real;
+            assert(!RB_TYPE_P(real, T_COMPLEX));
+            return real;
+        }
+        if (!k_numeric_p(num) || !f_real_p(num))
+            rb_raise(rb_eTypeError, "not a real");
     }
+    return num;
 }
 
 inline static VALUE
@@ -439,28 +446,28 @@ nucomp_s_canonicalize_internal(VALUE klass, VALUE real, VALUE imag)
     complex_r = RB_TYPE_P(real, T_COMPLEX);
     complex_i = RB_TYPE_P(imag, T_COMPLEX);
     if (!complex_r && !complex_i) {
-	return nucomp_s_new_internal(klass, real, imag);
+        return nucomp_s_new_internal(klass, real, imag);
     }
     else if (!complex_r) {
-	get_dat1(imag);
+        get_dat1(imag);
 
-	return nucomp_s_new_internal(klass,
-				     f_sub(real, dat->imag),
-				     f_add(ZERO, dat->real));
+        return nucomp_s_new_internal(klass,
+                                     f_sub(real, dat->imag),
+                                     f_add(ZERO, dat->real));
     }
     else if (!complex_i) {
-	get_dat1(real);
+        get_dat1(real);
 
-	return nucomp_s_new_internal(klass,
-				     dat->real,
-				     f_add(dat->imag, imag));
+        return nucomp_s_new_internal(klass,
+                                     dat->real,
+                                     f_add(dat->imag, imag));
     }
     else {
-	get_dat2(real, imag);
+        get_dat2(real, imag);
 
-	return nucomp_s_new_internal(klass,
-				     f_sub(adat->real, bdat->imag),
-				     f_add(adat->imag, bdat->real));
+        return nucomp_s_new_internal(klass,
+                                     f_sub(adat->real, bdat->imag),
+                                     f_add(adat->imag, bdat->real));
     }
 }
 
@@ -480,22 +487,26 @@ nucomp_s_new(int argc, VALUE *argv, VALUE klass)
 
     switch (rb_scan_args(argc, argv, "11", &real, &imag)) {
       case 1:
-	nucomp_real_check(real);
-	imag = ZERO;
-	break;
+        real = nucomp_real_check(real);
+        imag = ZERO;
+        break;
       default:
-	nucomp_real_check(real);
-	nucomp_real_check(imag);
-	break;
+        real = nucomp_real_check(real);
+        imag = nucomp_real_check(imag);
+        break;
     }
 
-    return nucomp_s_canonicalize_internal(klass, real, imag);
+    return nucomp_s_new_internal(klass, real, imag);
 }
 
 inline static VALUE
 f_complex_new2(VALUE klass, VALUE x, VALUE y)
 {
-    assert(!RB_TYPE_P(x, T_COMPLEX));
+    if (RB_TYPE_P(x, T_COMPLEX)) {
+        get_dat1(x);
+        x = dat->real;
+        y = f_add(dat->imag, y);
+    }
     return nucomp_s_canonicalize_internal(klass, x, y);
 }
 
@@ -550,7 +561,7 @@ nucomp_f_complex(int argc, VALUE *argv, VALUE klass)
     if (!NIL_P(opts)) {
         raise = rb_opts_exception_p(opts, raise);
     }
-    if (argc > 0 && CLASS_OF(a1) == rb_cComplex && a2 == Qundef) {
+    if (argc > 0 && CLASS_OF(a1) == rb_cComplex && UNDEF_P(a2)) {
         return a1;
     }
     return nucomp_convert(rb_cComplex, a1, a2, raise);
@@ -580,14 +591,14 @@ static VALUE
 m_cos(VALUE x)
 {
     if (!RB_TYPE_P(x, T_COMPLEX))
-	return m_cos_bang(x);
+        return m_cos_bang(x);
     {
-	get_dat1(x);
-	return f_complex_new2(rb_cComplex,
-			      f_mul(m_cos_bang(dat->real),
-				    m_cosh_bang(dat->imag)),
-			      f_mul(f_negate(m_sin_bang(dat->real)),
-				    m_sinh_bang(dat->imag)));
+        get_dat1(x);
+        return f_complex_new2(rb_cComplex,
+                              f_mul(m_cos_bang(dat->real),
+                                    m_cosh_bang(dat->imag)),
+                              f_mul(f_negate(m_sin_bang(dat->real)),
+                                    m_sinh_bang(dat->imag)));
     }
 }
 
@@ -595,55 +606,61 @@ static VALUE
 m_sin(VALUE x)
 {
     if (!RB_TYPE_P(x, T_COMPLEX))
-	return m_sin_bang(x);
+        return m_sin_bang(x);
     {
-	get_dat1(x);
-	return f_complex_new2(rb_cComplex,
-			      f_mul(m_sin_bang(dat->real),
-				    m_cosh_bang(dat->imag)),
-			      f_mul(m_cos_bang(dat->real),
-				    m_sinh_bang(dat->imag)));
+        get_dat1(x);
+        return f_complex_new2(rb_cComplex,
+                              f_mul(m_sin_bang(dat->real),
+                                    m_cosh_bang(dat->imag)),
+                              f_mul(m_cos_bang(dat->real),
+                                    m_sinh_bang(dat->imag)));
     }
 }
 
 static VALUE
-f_complex_polar(VALUE klass, VALUE x, VALUE y)
+f_complex_polar_real(VALUE klass, VALUE x, VALUE y)
 {
-    assert(!RB_TYPE_P(x, T_COMPLEX));
-    assert(!RB_TYPE_P(y, T_COMPLEX));
     if (f_zero_p(x) || f_zero_p(y)) {
-	return nucomp_s_new_internal(klass, x, RFLOAT_0);
+        return nucomp_s_new_internal(klass, x, RFLOAT_0);
     }
     if (RB_FLOAT_TYPE_P(y)) {
-	const double arg = RFLOAT_VALUE(y);
-	if (arg == M_PI) {
-	    x = f_negate(x);
-	    y = RFLOAT_0;
-	}
-	else if (arg == M_PI_2) {
-	    y = x;
-	    x = RFLOAT_0;
-	}
-	else if (arg == M_PI_2+M_PI) {
-	    y = f_negate(x);
-	    x = RFLOAT_0;
-	}
-	else if (RB_FLOAT_TYPE_P(x)) {
-	    const double abs = RFLOAT_VALUE(x);
-	    const double real = abs * cos(arg), imag = abs * sin(arg);
-	    x = DBL2NUM(real);
-	    y = DBL2NUM(imag);
-	}
-	else {
+        const double arg = RFLOAT_VALUE(y);
+        if (arg == M_PI) {
+            x = f_negate(x);
+            y = RFLOAT_0;
+        }
+        else if (arg == M_PI_2) {
+            y = x;
+            x = RFLOAT_0;
+        }
+        else if (arg == M_PI_2+M_PI) {
+            y = f_negate(x);
+            x = RFLOAT_0;
+        }
+        else if (RB_FLOAT_TYPE_P(x)) {
+            const double abs = RFLOAT_VALUE(x);
+            const double real = abs * cos(arg), imag = abs * sin(arg);
+            x = DBL2NUM(real);
+            y = DBL2NUM(imag);
+        }
+        else {
             const double ax = sin(arg), ay = cos(arg);
             y = f_mul(x, DBL2NUM(ax));
             x = f_mul(x, DBL2NUM(ay));
-	}
-	return nucomp_s_new_internal(klass, x, y);
+        }
+        return nucomp_s_new_internal(klass, x, y);
     }
     return nucomp_s_canonicalize_internal(klass,
-					  f_mul(x, m_cos(y)),
-					  f_mul(x, m_sin(y)));
+                                          f_mul(x, m_cos(y)),
+                                          f_mul(x, m_sin(y)));
+}
+
+static VALUE
+f_complex_polar(VALUE klass, VALUE x, VALUE y)
+{
+    x = nucomp_real_check(x);
+    y = nucomp_real_check(y);
+    return f_complex_polar_real(klass, x, y);
 }
 
 #ifdef HAVE___COSPI
@@ -665,12 +682,12 @@ rb_dbl_complex_new_polar_pi(double abs, double ang)
     int pos = fr == +0.5;
 
     if (pos || fr == -0.5) {
-	if ((modf(fi / 2.0, &fi) != fr) ^ pos) abs = -abs;
-	return rb_complex_new(RFLOAT_0, DBL2NUM(abs));
+        if ((modf(fi / 2.0, &fi) != fr) ^ pos) abs = -abs;
+        return rb_complex_new(RFLOAT_0, DBL2NUM(abs));
     }
     else if (fr == 0.0) {
-	if (modf(fi / 2.0, &fi) != 0.0) abs = -abs;
-	return DBL2NUM(abs);
+        if (modf(fi / 2.0, &fi) != 0.0) abs = -abs;
+        return DBL2NUM(abs);
     }
     else {
         const double real = abs * cospi(ang), imag = abs * sinpi(ang);
@@ -694,24 +711,15 @@ nucomp_s_polar(int argc, VALUE *argv, VALUE klass)
 {
     VALUE abs, arg;
 
-    switch (rb_scan_args(argc, argv, "11", &abs, &arg)) {
-      case 1:
-	nucomp_real_check(abs);
-	return nucomp_s_new_internal(klass, abs, ZERO);
-      default:
-	nucomp_real_check(abs);
-	nucomp_real_check(arg);
-	break;
-    }
-    if (RB_TYPE_P(abs, T_COMPLEX)) {
-        get_dat1(abs);
-        abs = dat->real;
+    argc = rb_scan_args(argc, argv, "11", &abs, &arg);
+    abs = nucomp_real_check(abs);
+    if (argc == 2) {
+        arg = nucomp_real_check(arg);
     }
-    if (RB_TYPE_P(arg, T_COMPLEX)) {
-        get_dat1(arg);
-        arg = dat->real;
+    else {
+        arg = ZERO;
     }
-    return f_complex_polar(klass, abs, arg);
+    return f_complex_polar_real(klass, abs, arg);
 }
 
 /*
@@ -760,7 +768,7 @@ rb_complex_uminus(VALUE self)
 {
     get_dat1(self);
     return f_complex_new2(CLASS_OF(self),
-			  f_negate(dat->real), f_negate(dat->imag));
+                          f_negate(dat->real), f_negate(dat->imag));
 }
 
 /*
@@ -779,20 +787,20 @@ VALUE
 rb_complex_plus(VALUE self, VALUE other)
 {
     if (RB_TYPE_P(other, T_COMPLEX)) {
-	VALUE real, imag;
+        VALUE real, imag;
 
-	get_dat2(self, other);
+        get_dat2(self, other);
 
-	real = f_add(adat->real, bdat->real);
-	imag = f_add(adat->imag, bdat->imag);
+        real = f_add(adat->real, bdat->real);
+        imag = f_add(adat->imag, bdat->imag);
 
-	return f_complex_new2(CLASS_OF(self), real, imag);
+        return f_complex_new2(CLASS_OF(self), real, imag);
     }
     if (k_numeric_p(other) && f_real_p(other)) {
-	get_dat1(self);
+        get_dat1(self);
 
-	return f_complex_new2(CLASS_OF(self),
-			      f_add(dat->real, other), dat->imag);
+        return f_complex_new2(CLASS_OF(self),
+                              f_add(dat->real, other), dat->imag);
     }
     return rb_num_coerce_bin(self, other, '+');
 }
@@ -813,33 +821,33 @@ VALUE
 rb_complex_minus(VALUE self, VALUE other)
 {
     if (RB_TYPE_P(other, T_COMPLEX)) {
-	VALUE real, imag;
+        VALUE real, imag;
 
-	get_dat2(self, other);
+        get_dat2(self, other);
 
-	real = f_sub(adat->real, bdat->real);
-	imag = f_sub(adat->imag, bdat->imag);
+        real = f_sub(adat->real, bdat->real);
+        imag = f_sub(adat->imag, bdat->imag);
 
-	return f_complex_new2(CLASS_OF(self), real, imag);
+        return f_complex_new2(CLASS_OF(self), real, imag);
     }
     if (k_numeric_p(other) && f_real_p(other)) {
-	get_dat1(self);
+        get_dat1(self);
 
-	return f_complex_new2(CLASS_OF(self),
-			      f_sub(dat->real, other), dat->imag);
+        return f_complex_new2(CLASS_OF(self),
+                              f_sub(dat->real, other), dat->imag);
     }
     return rb_num_coerce_bin(self, other, '-');
 }
 
 static VALUE
-safe_mul(VALUE a, VALUE b, int az, int bz)
+safe_mul(VALUE a, VALUE b, bool az, bool bz)
 {
     double v;
     if (!az && bz && RB_FLOAT_TYPE_P(a) && (v = RFLOAT_VALUE(a), !isnan(v))) {
-	a = signbit(v) ? DBL2NUM(-1.0) : DBL2NUM(1.0);
+        a = signbit(v) ? DBL2NUM(-1.0) : DBL2NUM(1.0);
     }
     if (!bz && az && RB_FLOAT_TYPE_P(b) && (v = RFLOAT_VALUE(b), !isnan(v))) {
-	b = signbit(v) ? DBL2NUM(-1.0) : DBL2NUM(1.0);
+        b = signbit(v) ? DBL2NUM(-1.0) : DBL2NUM(1.0);
     }
     return f_mul(a, b);
 }
@@ -847,10 +855,10 @@ safe_mul(VALUE a, VALUE b, int az, int bz)
 static void
 comp_mul(VALUE areal, VALUE aimag, VALUE breal, VALUE bimag, VALUE *real, VALUE *imag)
 {
-    int arzero = f_zero_p(areal);
-    int aizero = f_zero_p(aimag);
-    int brzero = f_zero_p(breal);
-    int bizero = f_zero_p(bimag);
+    bool arzero = f_zero_p(areal);
+    bool aizero = f_zero_p(aimag);
+    bool brzero = f_zero_p(breal);
+    bool bizero = f_zero_p(bimag);
     *real = f_sub(safe_mul(areal, breal, arzero, brzero),
                   safe_mul(aimag, bimag, aizero, bizero));
     *imag = f_add(safe_mul(areal, bimag, arzero, bizero),
@@ -873,47 +881,47 @@ VALUE
 rb_complex_mul(VALUE self, VALUE other)
 {
     if (RB_TYPE_P(other, T_COMPLEX)) {
-	VALUE real, imag;
-	get_dat2(self, other);
+        VALUE real, imag;
+        get_dat2(self, other);
 
         comp_mul(adat->real, adat->imag, bdat->real, bdat->imag, &real, &imag);
 
-	return f_complex_new2(CLASS_OF(self), real, imag);
+        return f_complex_new2(CLASS_OF(self), real, imag);
     }
     if (k_numeric_p(other) && f_real_p(other)) {
-	get_dat1(self);
+        get_dat1(self);
 
-	return f_complex_new2(CLASS_OF(self),
-			      f_mul(dat->real, other),
-			      f_mul(dat->imag, other));
+        return f_complex_new2(CLASS_OF(self),
+                              f_mul(dat->real, other),
+                              f_mul(dat->imag, other));
     }
     return rb_num_coerce_bin(self, other, '*');
 }
 
 inline static VALUE
 f_divide(VALUE self, VALUE other,
-	 VALUE (*func)(VALUE, VALUE), ID id)
+         VALUE (*func)(VALUE, VALUE), ID id)
 {
     if (RB_TYPE_P(other, T_COMPLEX)) {
         VALUE r, n, x, y;
-	int flo;
-	get_dat2(self, other);
+        int flo;
+        get_dat2(self, other);
 
-	flo = (RB_FLOAT_TYPE_P(adat->real) || RB_FLOAT_TYPE_P(adat->imag) ||
-	       RB_FLOAT_TYPE_P(bdat->real) || RB_FLOAT_TYPE_P(bdat->imag));
+        flo = (RB_FLOAT_TYPE_P(adat->real) || RB_FLOAT_TYPE_P(adat->imag) ||
+               RB_FLOAT_TYPE_P(bdat->real) || RB_FLOAT_TYPE_P(bdat->imag));
 
-	if (f_gt_p(f_abs(bdat->real), f_abs(bdat->imag))) {
-	    r = (*func)(bdat->imag, bdat->real);
-	    n = f_mul(bdat->real, f_add(ONE, f_mul(r, r)));
+        if (f_gt_p(f_abs(bdat->real), f_abs(bdat->imag))) {
+            r = (*func)(bdat->imag, bdat->real);
+            n = f_mul(bdat->real, f_add(ONE, f_mul(r, r)));
             x = (*func)(f_add(adat->real, f_mul(adat->imag, r)), n);
             y = (*func)(f_sub(adat->imag, f_mul(adat->real, r)), n);
-	}
-	else {
-	    r = (*func)(bdat->real, bdat->imag);
-	    n = f_mul(bdat->imag, f_add(ONE, f_mul(r, r)));
+        }
+        else {
+            r = (*func)(bdat->real, bdat->imag);
+            n = f_mul(bdat->imag, f_add(ONE, f_mul(r, r)));
             x = (*func)(f_add(f_mul(adat->real, r), adat->imag), n);
             y = (*func)(f_sub(f_mul(adat->imag, r), adat->real), n);
-	}
+        }
         if (!flo) {
             x = rb_rational_canonicalize(x);
             y = rb_rational_canonicalize(y);
@@ -922,7 +930,7 @@ f_divide(VALUE self, VALUE other,
     }
     if (k_numeric_p(other) && f_real_p(other)) {
         VALUE x, y;
-	get_dat1(self);
+        get_dat1(self);
         x = rb_rational_canonicalize((*func)(dat->real, other));
         y = rb_rational_canonicalize((*func)(dat->imag, other));
         return f_complex_new2(CLASS_OF(self), x, y);
@@ -986,31 +994,31 @@ VALUE
 rb_complex_pow(VALUE self, VALUE other)
 {
     if (k_numeric_p(other) && k_exact_zero_p(other))
-	return f_complex_new_bang1(CLASS_OF(self), ONE);
+        return f_complex_new_bang1(CLASS_OF(self), ONE);
 
     if (RB_TYPE_P(other, T_RATIONAL) && RRATIONAL(other)->den == LONG2FIX(1))
-	other = RRATIONAL(other)->num; /* c14n */
+        other = RRATIONAL(other)->num; /* c14n */
 
     if (RB_TYPE_P(other, T_COMPLEX)) {
-	get_dat1(other);
+        get_dat1(other);
 
-	if (k_exact_zero_p(dat->imag))
-	    other = dat->real; /* c14n */
+        if (k_exact_zero_p(dat->imag))
+            other = dat->real; /* c14n */
     }
 
     if (RB_TYPE_P(other, T_COMPLEX)) {
-	VALUE r, theta, nr, ntheta;
+        VALUE r, theta, nr, ntheta;
 
-	get_dat1(other);
+        get_dat1(other);
 
-	r = f_abs(self);
-	theta = f_arg(self);
+        r = f_abs(self);
+        theta = f_arg(self);
 
-	nr = m_exp_bang(f_sub(f_mul(dat->real, m_log_bang(r)),
-			      f_mul(dat->imag, theta)));
-	ntheta = f_add(f_mul(theta, dat->real),
-		       f_mul(dat->imag, m_log_bang(r)));
-	return f_complex_polar(CLASS_OF(self), nr, ntheta);
+        nr = m_exp_bang(f_sub(f_mul(dat->real, m_log_bang(r)),
+                              f_mul(dat->imag, theta)));
+        ntheta = f_add(f_mul(theta, dat->real),
+                       f_mul(dat->imag, m_log_bang(r)));
+        return f_complex_polar(CLASS_OF(self), nr, ntheta);
     }
     if (FIXNUM_P(other)) {
         long n = FIX2LONG(other);
@@ -1051,19 +1059,19 @@ rb_complex_pow(VALUE self, VALUE other)
                 }
             }
             return nucomp_s_new_internal(CLASS_OF(self), zr, zi);
-	}
+        }
     }
     if (k_numeric_p(other) && f_real_p(other)) {
-	VALUE r, theta;
+        VALUE r, theta;
 
-	if (RB_BIGNUM_TYPE_P(other))
-	    rb_warn("in a**b, b may be too big");
+        if (RB_BIGNUM_TYPE_P(other))
+            rb_warn("in a**b, b may be too big");
 
-	r = f_abs(self);
-	theta = f_arg(self);
+        r = f_abs(self);
+        theta = f_arg(self);
 
-	return f_complex_polar(CLASS_OF(self), f_expt(r, other),
-			       f_mul(theta, other));
+        return f_complex_polar(CLASS_OF(self), f_expt(r, other),
+                               f_mul(theta, other));
     }
     return rb_num_coerce_bin(self, other, id_expt);
 }
@@ -1084,15 +1092,15 @@ static VALUE
 nucomp_eqeq_p(VALUE self, VALUE other)
 {
     if (RB_TYPE_P(other, T_COMPLEX)) {
-	get_dat2(self, other);
+        get_dat2(self, other);
 
-	return RBOOL(f_eqeq_p(adat->real, bdat->real) &&
-			  f_eqeq_p(adat->imag, bdat->imag));
+        return RBOOL(f_eqeq_p(adat->real, bdat->real) &&
+                          f_eqeq_p(adat->imag, bdat->imag));
     }
     if (k_numeric_p(other) && f_real_p(other)) {
-	get_dat1(self);
+        get_dat1(self);
 
-	return RBOOL(f_eqeq_p(dat->real, other) && f_zero_p(dat->imag));
+        return RBOOL(f_eqeq_p(dat->real, other) && f_zero_p(dat->imag));
     }
     return RBOOL(f_eqeq_p(other, self));
 }
@@ -1101,7 +1109,7 @@ static bool
 nucomp_real_p(VALUE self)
 {
     get_dat1(self);
-    return(f_zero_p(dat->imag) ? true : false);
+    return f_zero_p(dat->imag);
 }
 
 /*
@@ -1121,15 +1129,26 @@ nucomp_real_p(VALUE self)
 static VALUE
 nucomp_cmp(VALUE self, VALUE other)
 {
-    if (nucomp_real_p(self) && k_numeric_p(other)) {
-        if (RB_TYPE_P(other, T_COMPLEX) && nucomp_real_p(other)) {
+    if (!k_numeric_p(other)) {
+        return rb_num_coerce_cmp(self, other, idCmp);
+    }
+    if (!nucomp_real_p(self)) {
+        return Qnil;
+    }
+    if (RB_TYPE_P(other, T_COMPLEX)) {
+        if (nucomp_real_p(other)) {
             get_dat2(self, other);
             return rb_funcall(adat->real, idCmp, 1, bdat->real);
         }
-        else if (f_real_p(other)) {
-            get_dat1(self);
+    }
+    else {
+        get_dat1(self);
+        if (f_real_p(other)) {
             return rb_funcall(dat->real, idCmp, 1, other);
         }
+        else {
+            return rb_num_coerce_cmp(dat->real, other, idCmp);
+        }
     }
     return Qnil;
 }
@@ -1139,12 +1158,12 @@ static VALUE
 nucomp_coerce(VALUE self, VALUE other)
 {
     if (RB_TYPE_P(other, T_COMPLEX))
-	return rb_assoc_new(other, self);
+        return rb_assoc_new(other, self);
     if (k_numeric_p(other) && f_real_p(other))
         return rb_assoc_new(f_complex_new_bang1(CLASS_OF(self), other), self);
 
     rb_raise(rb_eTypeError, "%"PRIsVALUE" can't be coerced into %"PRIsVALUE,
-	     rb_obj_class(other), rb_obj_class(self));
+             rb_obj_class(other), rb_obj_class(self));
     return Qnil;
 }
 
@@ -1164,16 +1183,16 @@ rb_complex_abs(VALUE self)
     get_dat1(self);
 
     if (f_zero_p(dat->real)) {
-	VALUE a = f_abs(dat->imag);
-	if (RB_FLOAT_TYPE_P(dat->real) && !RB_FLOAT_TYPE_P(dat->imag))
-	    a = f_to_f(a);
-	return a;
+        VALUE a = f_abs(dat->imag);
+        if (RB_FLOAT_TYPE_P(dat->real) && !RB_FLOAT_TYPE_P(dat->imag))
+            a = f_to_f(a);
+        return a;
     }
     if (f_zero_p(dat->imag)) {
-	VALUE a = f_abs(dat->real);
-	if (!RB_FLOAT_TYPE_P(dat->real) && RB_FLOAT_TYPE_P(dat->imag))
-	    a = f_to_f(a);
-	return a;
+        VALUE a = f_abs(dat->real);
+        if (!RB_FLOAT_TYPE_P(dat->real) && RB_FLOAT_TYPE_P(dat->imag))
+            a = f_to_f(a);
+        return a;
     }
     return rb_math_hypot(dat->real, dat->imag);
 }
@@ -1192,7 +1211,7 @@ nucomp_abs2(VALUE self)
 {
     get_dat1(self);
     return f_add(f_mul(dat->real, dat->real),
-		 f_mul(dat->imag, dat->imag));
+                 f_mul(dat->imag, dat->imag));
 }
 
 /*
@@ -1313,10 +1332,10 @@ nucomp_numerator(VALUE self)
 
     cd = nucomp_denominator(self);
     return f_complex_new2(CLASS_OF(self),
-			  f_mul(f_numerator(dat->real),
-				f_div(cd, f_denominator(dat->real))),
-			  f_mul(f_numerator(dat->imag),
-				f_div(cd, f_denominator(dat->imag))));
+                          f_mul(f_numerator(dat->real),
+                                f_div(cd, f_denominator(dat->real))),
+                          f_mul(f_numerator(dat->imag),
+                                f_div(cd, f_denominator(dat->imag))));
 }
 
 /* :nodoc: */
@@ -1346,11 +1365,11 @@ static VALUE
 nucomp_eql_p(VALUE self, VALUE other)
 {
     if (RB_TYPE_P(other, T_COMPLEX)) {
-	get_dat2(self, other);
+        get_dat2(self, other);
 
-	return RBOOL((CLASS_OF(adat->real) == CLASS_OF(bdat->real)) &&
-			  (CLASS_OF(adat->imag) == CLASS_OF(bdat->imag)) &&
-			  f_eqeq_p(self, other));
+        return RBOOL((CLASS_OF(adat->real) == CLASS_OF(bdat->real)) &&
+                          (CLASS_OF(adat->imag) == CLASS_OF(bdat->imag)) &&
+                          f_eqeq_p(self, other));
 
     }
     return Qfalse;
@@ -1360,8 +1379,8 @@ inline static int
 f_signbit(VALUE x)
 {
     if (RB_FLOAT_TYPE_P(x)) {
-	double f = RFLOAT_VALUE(x);
-	return !isnan(f) && signbit(f);
+        double f = RFLOAT_VALUE(x);
+        return !isnan(f) && signbit(f);
     }
     return f_negative_p(x);
 }
@@ -1387,7 +1406,7 @@ f_format(VALUE self, VALUE (*func)(VALUE))
 
     rb_str_concat(s, (*func)(f_abs(dat->imag)));
     if (!rb_isdigit(RSTRING_PTR(s)[RSTRING_LEN(s) - 1]))
-	rb_str_cat2(s, "*");
+        rb_str_cat2(s, "*");
     rb_str_cat2(s, "i");
 
     return s;
@@ -1470,7 +1489,7 @@ rb_complex_infinite_p(VALUE self)
     get_dat1(self);
 
     if (!f_infinite_p(dat->real) && !f_infinite_p(dat->imag)) {
-	return Qnil;
+        return Qnil;
     }
     return ONE;
 }
@@ -1513,7 +1532,7 @@ nucomp_marshal_load(VALUE self, VALUE a)
 {
     Check_Type(a, T_ARRAY);
     if (RARRAY_LEN(a) != 2)
-	rb_raise(rb_eArgError, "marshaled complex must have an array whose length is 2 but %ld", RARRAY_LEN(a));
+        rb_raise(rb_eArgError, "marshaled complex must have an array whose length is 2 but %ld", RARRAY_LEN(a));
     rb_ivar_set(self, id_i_real, RARRAY_AREF(a, 0));
     rb_ivar_set(self, id_i_imag, RARRAY_AREF(a, 1));
     return self;
@@ -1575,8 +1594,8 @@ nucomp_to_i(VALUE self)
     get_dat1(self);
 
     if (!k_exact_zero_p(dat->imag)) {
-	rb_raise(rb_eRangeError, "can't convert %"PRIsVALUE" into Integer",
-		 self);
+        rb_raise(rb_eRangeError, "can't convert %"PRIsVALUE" into Integer",
+                 self);
     }
     return f_to_i(dat->real);
 }
@@ -1598,8 +1617,8 @@ nucomp_to_f(VALUE self)
     get_dat1(self);
 
     if (!k_exact_zero_p(dat->imag)) {
-	rb_raise(rb_eRangeError, "can't convert %"PRIsVALUE" into Float",
-		 self);
+        rb_raise(rb_eRangeError, "can't convert %"PRIsVALUE" into Float",
+                 self);
     }
     return f_to_f(dat->real);
 }
@@ -1623,8 +1642,8 @@ nucomp_to_r(VALUE self)
     get_dat1(self);
 
     if (!k_exact_zero_p(dat->imag)) {
-	rb_raise(rb_eRangeError, "can't convert %"PRIsVALUE" into Rational",
-		 self);
+        rb_raise(rb_eRangeError, "can't convert %"PRIsVALUE" into Rational",
+                 self);
     }
     return f_to_r(dat->real);
 }
@@ -1703,14 +1722,14 @@ issign(int c)
 
 static int
 read_sign(const char **s,
-	  char **b)
+          char **b)
 {
     int sign = '?';
 
     if (issign(**s)) {
-	sign = **b = **s;
-	(*s)++;
-	(*b)++;
+        sign = **b = **s;
+        (*s)++;
+        (*b)++;
     }
     return sign;
 }
@@ -1723,32 +1742,32 @@ isdecimal(int c)
 
 static int
 read_digits(const char **s, int strict,
-	    char **b)
+            char **b)
 {
     int us = 1;
 
     if (!isdecimal(**s))
-	return 0;
+        return 0;
 
     while (isdecimal(**s) || **s == '_') {
-	if (**s == '_') {
-	    if (strict) {
-		if (us)
-		    return 0;
-	    }
-	    us = 1;
-	}
-	else {
-	    **b = **s;
-	    (*b)++;
-	    us = 0;
-	}
-	(*s)++;
+        if (**s == '_') {
+            if (us) {
+                if (strict) return 0;
+                break;
+            }
+            us = 1;
+        }
+        else {
+            **b = **s;
+            (*b)++;
+            us = 0;
+        }
+        (*s)++;
     }
     if (us)
-	do {
-	    (*s)--;
-	} while (**s == '_');
+        do {
+            (*s)--;
+        } while (**s == '_');
     return 1;
 }
 
@@ -1760,70 +1779,70 @@ islettere(int c)
 
 static int
 read_num(const char **s, int strict,
-	 char **b)
+         char **b)
 {
     if (**s != '.') {
-	if (!read_digits(s, strict, b))
-	    return 0;
+        if (!read_digits(s, strict, b))
+            return 0;
     }
 
     if (**s == '.') {
-	**b = **s;
-	(*s)++;
-	(*b)++;
-	if (!read_digits(s, strict, b)) {
-	    (*b)--;
-	    return 0;
-	}
+        **b = **s;
+        (*s)++;
+        (*b)++;
+        if (!read_digits(s, strict, b)) {
+            (*b)--;
+            return 0;
+        }
     }
 
     if (islettere(**s)) {
-	**b = **s;
-	(*s)++;
-	(*b)++;
-	read_sign(s, b);
-	if (!read_digits(s, strict, b)) {
-	    (*b)--;
-	    return 0;
-	}
+        **b = **s;
+        (*s)++;
+        (*b)++;
+        read_sign(s, b);
+        if (!read_digits(s, strict, b)) {
+            (*b)--;
+            return 0;
+        }
     }
     return 1;
 }
 
 inline static int
 read_den(const char **s, int strict,
-	 char **b)
+         char **b)
 {
     if (!read_digits(s, strict, b))
-	return 0;
+        return 0;
     return 1;
 }
 
 static int
 read_rat_nos(const char **s, int strict,
-	     char **b)
+             char **b)
 {
     if (!read_num(s, strict, b))
-	return 0;
+        return 0;
     if (**s == '/') {
-	**b = **s;
-	(*s)++;
-	(*b)++;
-	if (!read_den(s, strict, b)) {
-	    (*b)--;
-	    return 0;
-	}
+        **b = **s;
+        (*s)++;
+        (*b)++;
+        if (!read_den(s, strict, b)) {
+            (*b)--;
+            return 0;
+        }
     }
     return 1;
 }
 
 static int
 read_rat(const char **s, int strict,
-	 char **b)
+         char **b)
 {
     read_sign(s, b);
     if (!read_rat_nos(s, strict, b))
-	return 0;
+        return 0;
     return 1;
 }
 
@@ -1831,22 +1850,22 @@ inline static int
 isimagunit(int c)
 {
     return (c == 'i' || c == 'I' ||
-	    c == 'j' || c == 'J');
+            c == 'j' || c == 'J');
 }
 
 static VALUE
 str2num(char *s)
 {
     if (strchr(s, '/'))
-	return rb_cstr_to_rat(s, 0);
+        return rb_cstr_to_rat(s, 0);
     if (strpbrk(s, ".eE"))
-	return DBL2NUM(rb_cstr_to_dbl(s, 0));
+        return DBL2NUM(rb_cstr_to_dbl(s, 0));
     return rb_cstr_to_inum(s, 10, 0);
 }
 
 static int
 read_comp(const char **s, int strict,
-	  VALUE *ret, char **b)
+          VALUE *ret, char **b)
 {
     char *bb;
     int sign;
@@ -1857,72 +1876,72 @@ read_comp(const char **s, int strict,
     sign = read_sign(s, b);
 
     if (isimagunit(**s)) {
-	(*s)++;
-	num = INT2FIX((sign == '-') ? -1 : + 1);
-	*ret = rb_complex_new2(ZERO, num);
-	return 1; /* e.g. "i" */
+        (*s)++;
+        num = INT2FIX((sign == '-') ? -1 : + 1);
+        *ret = rb_complex_new2(ZERO, num);
+        return 1; /* e.g. "i" */
     }
 
     if (!read_rat_nos(s, strict, b)) {
-	**b = '\0';
-	num = str2num(bb);
-	*ret = rb_complex_new2(num, ZERO);
-	return 0; /* e.g. "-" */
+        **b = '\0';
+        num = str2num(bb);
+        *ret = rb_complex_new2(num, ZERO);
+        return 0; /* e.g. "-" */
     }
     **b = '\0';
     num = str2num(bb);
 
     if (isimagunit(**s)) {
-	(*s)++;
-	*ret = rb_complex_new2(ZERO, num);
-	return 1; /* e.g. "3i" */
+        (*s)++;
+        *ret = rb_complex_new2(ZERO, num);
+        return 1; /* e.g. "3i" */
     }
 
     if (**s == '@') {
-	int st;
-
-	(*s)++;
-	bb = *b;
-	st = read_rat(s, strict, b);
-	**b = '\0';
-	if (strlen(bb) < 1 ||
-	    !isdecimal(*(bb + strlen(bb) - 1))) {
-	    *ret = rb_complex_new2(num, ZERO);
-	    return 0; /* e.g. "1@-" */
-	}
-	num2 = str2num(bb);
-	*ret = rb_complex_new_polar(num, num2);
-	if (!st)
-	    return 0; /* e.g. "1@2." */
-	else
-	    return 1; /* e.g. "1@2" */
+        int st;
+
+        (*s)++;
+        bb = *b;
+        st = read_rat(s, strict, b);
+        **b = '\0';
+        if (strlen(bb) < 1 ||
+            !isdecimal(*(bb + strlen(bb) - 1))) {
+            *ret = rb_complex_new2(num, ZERO);
+            return 0; /* e.g. "1@-" */
+        }
+        num2 = str2num(bb);
+        *ret = rb_complex_new_polar(num, num2);
+        if (!st)
+            return 0; /* e.g. "1@2." */
+        else
+            return 1; /* e.g. "1@2" */
     }
 
     if (issign(**s)) {
-	bb = *b;
-	sign = read_sign(s, b);
-	if (isimagunit(**s))
-	    num2 = INT2FIX((sign == '-') ? -1 : + 1);
-	else {
-	    if (!read_rat_nos(s, strict, b)) {
-		*ret = rb_complex_new2(num, ZERO);
-		return 0; /* e.g. "1+xi" */
-	    }
-	    **b = '\0';
-	    num2 = str2num(bb);
-	}
-	if (!isimagunit(**s)) {
-	    *ret = rb_complex_new2(num, ZERO);
-	    return 0; /* e.g. "1+3x" */
-	}
-	(*s)++;
-	*ret = rb_complex_new2(num, num2);
-	return 1; /* e.g. "1+2i" */
+        bb = *b;
+        sign = read_sign(s, b);
+        if (isimagunit(**s))
+            num2 = INT2FIX((sign == '-') ? -1 : + 1);
+        else {
+            if (!read_rat_nos(s, strict, b)) {
+                *ret = rb_complex_new2(num, ZERO);
+                return 0; /* e.g. "1+xi" */
+            }
+            **b = '\0';
+            num2 = str2num(bb);
+        }
+        if (!isimagunit(**s)) {
+            *ret = rb_complex_new2(num, ZERO);
+            return 0; /* e.g. "1+3x" */
+        }
+        (*s)++;
+        *ret = rb_complex_new2(num, num2);
+        return 1; /* e.g. "1+2i" */
     }
     /* !(@, - or +) */
     {
-	*ret = rb_complex_new2(num, ZERO);
-	return 1; /* e.g. "3" */
+        *ret = rb_complex_new2(num, ZERO);
+        return 1; /* e.g. "3" */
     }
 }
 
@@ -1930,7 +1949,7 @@ inline static void
 skip_ws(const char **s)
 {
     while (isspace((unsigned char)**s))
-	(*s)++;
+        (*s)++;
 }
 
 static int
@@ -1971,22 +1990,22 @@ string_to_c_strict(VALUE self, int raise)
 
     if (!s || memchr(s, '\0', RSTRING_LEN(self))) {
         if (!raise) return Qnil;
-	rb_raise(rb_eArgError, "string contains null byte");
+        rb_raise(rb_eArgError, "string contains null byte");
     }
 
     if (s && s[RSTRING_LEN(self)]) {
-	rb_str_modify(self);
-	s = RSTRING_PTR(self);
-	s[RSTRING_LEN(self)] = '\0';
+        rb_str_modify(self);
+        s = RSTRING_PTR(self);
+        s[RSTRING_LEN(self)] = '\0';
     }
 
     if (!s)
-	s = (char *)"";
+        s = (char *)"";
 
     if (!parse_comp(s, 1, &num)) {
         if (!raise) return Qnil;
-	rb_raise(rb_eArgError, "invalid value for convert(): %+"PRIsVALUE,
-		 self);
+        rb_raise(rb_eArgError, "invalid value for convert(): %+"PRIsVALUE,
+                 self);
     }
 
     return num;
@@ -2013,6 +2032,12 @@ string_to_c_strict(VALUE self, int raise)
  *    '1/2+3/4i'.to_c    #=> ((1/2)+(3/4)*i)
  *    'ruby'.to_c        #=> (0+0i)
  *
+ * Polar form:
+ *    include Math
+ *    "1.0@0".to_c        #=> (1+0.0i)
+ *    "1.0@#{PI/2}".to_c  #=> (0.0+1i)
+ *    "1.0@#{PI}".to_c    #=> (-1+0.0i)
+ *
  * See Kernel.Complex.
  */
 static VALUE
@@ -2026,13 +2051,13 @@ string_to_c(VALUE self)
     s = RSTRING_PTR(self);
 
     if (s && s[RSTRING_LEN(self)]) {
-	rb_str_modify(self);
-	s = RSTRING_PTR(self);
-	s[RSTRING_LEN(self)] = '\0';
+        rb_str_modify(self);
+        s = RSTRING_PTR(self);
+        s[RSTRING_LEN(self)] = '\0';
     }
 
     if (!s)
-	s = (char *)"";
+        s = (char *)"";
 
     (void)parse_comp(s, 0, &num);
 
@@ -2050,65 +2075,68 @@ nucomp_convert(VALUE klass, VALUE a1, VALUE a2, int raise)
 {
     if (NIL_P(a1) || NIL_P(a2)) {
         if (!raise) return Qnil;
-	rb_raise(rb_eTypeError, "can't convert nil into Complex");
+        rb_raise(rb_eTypeError, "can't convert nil into Complex");
     }
 
     if (RB_TYPE_P(a1, T_STRING)) {
-	a1 = string_to_c_strict(a1, raise);
+        a1 = string_to_c_strict(a1, raise);
         if (NIL_P(a1)) return Qnil;
     }
 
     if (RB_TYPE_P(a2, T_STRING)) {
-	a2 = string_to_c_strict(a2, raise);
+        a2 = string_to_c_strict(a2, raise);
         if (NIL_P(a2)) return Qnil;
     }
 
     if (RB_TYPE_P(a1, T_COMPLEX)) {
-	{
-	    get_dat1(a1);
+        {
+            get_dat1(a1);
 
-	    if (k_exact_zero_p(dat->imag))
-		a1 = dat->real;
-	}
+            if (k_exact_zero_p(dat->imag))
+                a1 = dat->real;
+        }
     }
 
     if (RB_TYPE_P(a2, T_COMPLEX)) {
-	{
-	    get_dat1(a2);
+        {
+            get_dat1(a2);
 
-	    if (k_exact_zero_p(dat->imag))
-		a2 = dat->real;
-	}
+            if (k_exact_zero_p(dat->imag))
+                a2 = dat->real;
+        }
     }
 
     if (RB_TYPE_P(a1, T_COMPLEX)) {
-	if (a2 == Qundef || (k_exact_zero_p(a2)))
-	    return a1;
-    }
-
-    if (a2 == Qundef) {
-	if (k_numeric_p(a1) && !f_real_p(a1))
-	    return a1;
-	/* should raise exception for consistency */
-	if (!k_numeric_p(a1)) {
-            if (!raise)
-                return rb_protect(to_complex, a1, NULL);
-	    return to_complex(a1);
+        if (UNDEF_P(a2) || (k_exact_zero_p(a2)))
+            return a1;
+    }
+
+    if (UNDEF_P(a2)) {
+        if (k_numeric_p(a1) && !f_real_p(a1))
+            return a1;
+        /* should raise exception for consistency */
+        if (!k_numeric_p(a1)) {
+            if (!raise) {
+                a1 = rb_protect(to_complex, a1, NULL);
+                rb_set_errinfo(Qnil);
+                return a1;
+            }
+            return to_complex(a1);
         }
     }
     else {
-	if ((k_numeric_p(a1) && k_numeric_p(a2)) &&
-	    (!f_real_p(a1) || !f_real_p(a2)))
-	    return f_add(a1,
-			 f_mul(a2,
-			       f_complex_new_bang2(rb_cComplex, ZERO, ONE)));
+        if ((k_numeric_p(a1) && k_numeric_p(a2)) &&
+            (!f_real_p(a1) || !f_real_p(a2)))
+            return f_add(a1,
+                         f_mul(a2,
+                               f_complex_new_bang2(rb_cComplex, ZERO, ONE)));
     }
 
     {
         int argc;
-	VALUE argv2[2];
-	argv2[0] = a1;
-        if (a2 == Qundef) {
+        VALUE argv2[2];
+        argv2[0] = a1;
+        if (UNDEF_P(a2)) {
             argv2[1] = Qnil;
             argc = 1;
         }
@@ -2118,7 +2146,7 @@ nucomp_convert(VALUE klass, VALUE a1, VALUE a2, int raise)
             argv2[1] = a2;
             argc = 2;
         }
-	return nucomp_s_new(argc, argv2, klass);
+        return nucomp_s_new(argc, argv2, klass);
     }
 }
 
@@ -2136,31 +2164,6 @@ nucomp_s_convert(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    num.real  ->  self
- *
- * Returns self.
- */
-static VALUE
-numeric_real(VALUE self)
-{
-    return self;
-}
-
-/*
- * call-seq:
- *    num.imag       ->  0
- *    num.imaginary  ->  0
- *
- * Returns zero.
- */
-static VALUE
-numeric_imag(VALUE self)
-{
-    return INT2FIX(0);
-}
-
-/*
- * call-seq:
  *    num.abs2  ->  real
  *
  * Returns square of self.
@@ -2232,19 +2235,6 @@ numeric_polar(VALUE self)
 
 /*
  * call-seq:
- *    num.conj       ->  self
- *    num.conjugate  ->  self
- *
- * Returns self.
- */
-static VALUE
-numeric_conj(VALUE self)
-{
-    return self;
-}
-
-/*
- * call-seq:
  *    flo.arg    ->  0 or float
  *    flo.angle  ->  0 or float
  *    flo.phase  ->  0 or float
@@ -2255,9 +2245,9 @@ static VALUE
 float_arg(VALUE self)
 {
     if (isnan(RFLOAT_VALUE(self)))
-	return self;
+        return self;
     if (f_tpositive_p(self))
-	return INT2FIX(0);
+        return INT2FIX(0);
     return rb_const_get(rb_mMath, id_PI);
 }
 
@@ -2408,9 +2398,6 @@ Init_Complex(void)
 
     rb_define_private_method(CLASS_OF(rb_cComplex), "convert", nucomp_s_convert, -1);
 
-    rb_define_method(rb_cNumeric, "real", numeric_real, 0);
-    rb_define_method(rb_cNumeric, "imaginary", numeric_imag, 0);
-    rb_define_method(rb_cNumeric, "imag", numeric_imag, 0);
     rb_define_method(rb_cNumeric, "abs2", numeric_abs2, 0);
     rb_define_method(rb_cNumeric, "arg", numeric_arg, 0);
     rb_define_method(rb_cNumeric, "angle", numeric_arg, 0);
@@ -2418,8 +2405,6 @@ Init_Complex(void)
     rb_define_method(rb_cNumeric, "rectangular", numeric_rect, 0);
     rb_define_method(rb_cNumeric, "rect", numeric_rect, 0);
     rb_define_method(rb_cNumeric, "polar", numeric_polar, 0);
-    rb_define_method(rb_cNumeric, "conjugate", numeric_conj, 0);
-    rb_define_method(rb_cNumeric, "conj", numeric_conj, 0);
 
     rb_define_method(rb_cFloat, "arg", float_arg, 0);
     rb_define_method(rb_cFloat, "angle", float_arg, 0);
@@ -2429,7 +2414,7 @@ Init_Complex(void)
      * The imaginary unit.
      */
     rb_define_const(rb_cComplex, "I",
-		    f_complex_new_bang2(rb_cComplex, ZERO, ONE));
+                    f_complex_new_bang2(rb_cComplex, ZERO, ONE));
 
 #if !USE_FLONUM
     rb_gc_register_mark_object(RFLOAT_0 = DBL2NUM(0.0));
diff --git a/configure.ac b/configure.ac
index cbc53231d8..220392d120 100644
--- a/configure.ac
+++ b/configure.ac
@@ -32,6 +32,7 @@ m4_include([tool/m4/ruby_func_attribute.m4])dnl
 m4_include([tool/m4/ruby_mingw32.m4])dnl
 m4_include([tool/m4/ruby_prepend_option.m4])dnl
 m4_include([tool/m4/ruby_prog_gnu_ld.m4])dnl
+m4_include([tool/m4/ruby_prog_makedirs.m4])dnl
 m4_include([tool/m4/ruby_replace_funcs.m4])dnl
 m4_include([tool/m4/ruby_replace_type.m4])dnl
 m4_include([tool/m4/ruby_require_funcs.m4])dnl
@@ -63,14 +64,22 @@ AC_ARG_WITH(baseruby,
 	[
 		AC_PATH_PROG([BASERUBY], [ruby], [false])
 	])
+# BASERUBY must be >= 2.2.0. Note that `"2.2.0" > "2.2"` is true.
 AS_IF([test "$HAVE_BASERUBY" != no -a "`RUBYOPT=- $BASERUBY --disable=gems -e 'print 42 if RUBY_VERSION > "2.2"' 2>/dev/null`" = 42], [
+    AS_CASE(["$build_os"], [mingw*], [
+        # Can MSys shell run a command with a drive letter?
+        RUBYOPT=- `cygpath -ma "$BASERUBY"` --disable=gems -e exit 2>/dev/null || HAVE_BASERUBY=no
+    ])
     BASERUBY="$BASERUBY --disable=gems"
     BASERUBY_VERSION=`$BASERUBY -v`
     $BASERUBY -C "$srcdir" tool/downloader.rb -d tool -e gnu config.guess config.sub >&AS_MESSAGE_FD
 ], [
-    BASERUBY="echo executable host ruby is required.  use --with-baseruby option.; false"
     HAVE_BASERUBY=no
 ])
+AS_IF([test "$HAVE_BASERUBY" = no], [
+    AS_IF([test "$cross_compiling" = yes], [AC_MSG_ERROR([executable host ruby is required for cross-compiling])])
+    BASERUBY="echo executable host ruby is required.  use --with-baseruby option.; false"
+])
 AC_SUBST(BASERUBY)
 AC_SUBST(HAVE_BASERUBY)
 
@@ -87,7 +96,9 @@ AC_SUBST(GIT)
 AC_SUBST(HAVE_GIT)
 
 eval `sed -n -e ['s/^@%:@define RUBY_[A-Z_]*VERSION_\([A-Z][A-Z][A-Z_0-9]*\) \([0-9][0-9]*\)$/\1=\2/p'] \
+      -e ['s/^@%:@define \(RUBY_ABI_VERSION\) \([0-9][0-9]*\).*/\1=\2/p'] \
       -e ['s/^@%:@define \(RUBY_PATCHLEVEL\) \(.*\)/\1=\2/p'] \
+     $srcdir/include/ruby/internal/abi.h \
      $srcdir/include/ruby/version.h $srcdir/version.h`
 for v in MAJOR MINOR TEENY; do
     AS_IF([eval "test \"\$$v\" = ''"], [
@@ -99,6 +110,9 @@ AC_SUBST(MINOR)
 AC_SUBST(TEENY)
 AC_SUBST(RUBY_API_VERSION, '$(MAJOR).$(MINOR)')
 AC_SUBST(RUBY_PROGRAM_VERSION, '$(MAJOR).$(MINOR).$(TEENY)')
+AS_CASE([$RUBY_PATCHLEVEL], [-*], [
+    AC_DEFINE_UNQUOTED(RUBY_ABI_VERSION, [${RUBY_ABI_VERSION}])
+], [RUBY_ABI_VERSION=])
 
 AS_IF([test "$program_prefix" = NONE], [
   program_prefix=
@@ -119,9 +133,12 @@ AC_CANONICAL_TARGET
 AS_CASE(["$target_cpu-$target_os"],
     [aarch64-darwin*], [
         target_cpu=arm64
-        AS_CASE(["$target_vendor"], [unknown], [target_vendor=apple target=${target/-unknown-/-apple-}])
-        target="${target/aarch64/arm64}"
-        target_alias="${target_alias/aarch64/arm64}"
+        AS_CASE(["$target_vendor"], [unknown], [
+            target_vendor=apple
+            target=${target%%-unknown-*}-apple-${target@%:@*-unknown-}
+        ])
+        target="arm64-${target@%:@aarch64-}"
+        AS_IF([test -n "$target_alias"], [target_alias="arm64-${target_alias@%:@aarch64-}"])
     ])
 
 AC_ARG_PROGRAM
@@ -197,15 +214,23 @@ AS_CASE(["/${rb_CC} "],
 [*clang*],            [
     # Ditto for LLVM.  Note however that llvm-as is a LLVM-IR to LLVM bitcode
     # assembler that does not target your machine native binary.
-    : ${LD:="${CC}"}         # ... try -fuse-ld=lld ?
-    RUBY_CHECK_PROG_FOR_CC([AR],      [s/clang/llvm-ar/])
-#   RUBY_CHECK_PROG_FOR_CC([AS],      [s/clang/llvm-as/])
+
+    # Xcode has its own version tools that may be incompatible with
+    # genuine LLVM tools, use the tools in the same directory.
+
+    AS_IF([$rb_CC -E -dM -xc - < /dev/null | grep -F __apple_build_version__ > /dev/null],
+          [llvm_prefix=], [llvm_prefix=llvm-])
+    # AC_PREPROC_IFELSE cannot be used before AC_USE_SYSTEM_EXTENSIONS
+
+    RUBY_CHECK_PROG_FOR_CC([LD],      [s/clang/ld/]) # ... maybe try lld ?
+    RUBY_CHECK_PROG_FOR_CC([AR],      [s/clang/${llvm_prefix}ar/])
+#   RUBY_CHECK_PROG_FOR_CC([AS],      [s/clang/${llvm_prefix}as/])
     RUBY_CHECK_PROG_FOR_CC([CXX],     [s/clang/clang++/])
-    RUBY_CHECK_PROG_FOR_CC([NM],      [s/clang/llvm-nm/])
-    RUBY_CHECK_PROG_FOR_CC([OBJCOPY], [s/clang/llvm-objcopy/])
-    RUBY_CHECK_PROG_FOR_CC([OBJDUMP], [s/clang/llvm-objdump/])
-    RUBY_CHECK_PROG_FOR_CC([RANLIB],  [s/clang/llvm-ranlib/])
-    RUBY_CHECK_PROG_FOR_CC([STRIP],   [s/clang/llvm-strip/])
+    RUBY_CHECK_PROG_FOR_CC([NM],      [s/clang/${llvm_prefix}nm/])
+    RUBY_CHECK_PROG_FOR_CC([OBJCOPY], [s/clang/${llvm_prefix}objcopy/])
+    RUBY_CHECK_PROG_FOR_CC([OBJDUMP], [s/clang/${llvm_prefix}objdump/])
+    RUBY_CHECK_PROG_FOR_CC([RANLIB],  [s/clang/${llvm_prefix}ranlib/])
+    RUBY_CHECK_PROG_FOR_CC([STRIP],   [s/clang/${llvm_prefix}strip/])
 ])
 AS_UNSET(rb_CC)
 AS_UNSET(rb_dummy)
@@ -346,10 +371,9 @@ AS_CASE(["$target_os"],
 	[!<===== pre OS X 10.5 =====>]
 	@%:@endif
 	]])],
-	[macosx_min_required=yes],
+	[AC_MSG_RESULT(yes)],
 	[AC_MSG_RESULT(no)
 	AC_MSG_ERROR([Unsupported OS X version is required])])
-    AC_MSG_RESULT(${macosx_min_required})
 ])
 
 RUBY_MINGW32
@@ -365,14 +389,21 @@ AS_IF([test "$GCC" = yes], [
     icc_version=`echo =__ICC | $CC -E -xc - | sed '/^=/!d;s///;/^__ICC/d'`
     test -n "$icc_version" || icc_version=0
     # RUBY_APPEND_OPTIONS(XCFLAGS, ["-include ruby/config.h" "-include ruby/missing.h"])
+
+    AS_IF([test "$gcc_major" -lt 4], [
+        AC_MSG_ERROR([too old GCC: $gcc_major.$gcc_minor])
+    ])
+
+    AC_CACHE_CHECK([if thread-local storage is supported], [rb_cv_tls_supported],
+        [AC_LINK_IFELSE([AC_LANG_PROGRAM([[int __thread conftest;]])],
+            [rb_cv_tls_supported=yes],
+            [rb_cv_tls_supported=no])])
+    AS_IF([test x"$rb_cv_tls_supported" != xyes],
+        [AC_DEFINE(RB_THREAD_LOCAL_SPECIFIER_IS_UNSUPPORTED)])
 ], [
     linker_flag=
 ])
 
-AS_IF([test "$GCC" = yes -a "$gcc_major" -lt 3 ], [
-    AC_MSG_ERROR([too old GCC])
-])
-
 RUBY_PROG_GNU_LD
 RUBY_CPPOUTFILE
 
@@ -479,6 +510,7 @@ AS_CASE(["$target_os"],
 	AC_DEFINE_UNQUOTED(RUBY_MSVCRT_VERSION, $RT_VER)
 	sysconfdir=
     ])
+    rb_cv_binary_elf=no
     : ${enable_shared=yes}
     ],
 [hiuxmpp*], [AC_DEFINE(__HIUX_MPP__)])    # by TOYODA Eizi <toyoda@npd.kishou.go.jp>
@@ -486,17 +518,12 @@ AS_CASE(["$target_os"],
 AC_PROG_LN_S
 AC_PROG_MAKE_SET
 AC_PROG_INSTALL
-AC_PROG_MKDIR_P
-AS_IF([test "x$MKDIR_P" = "x -d"], [
-  AS_IF([test x"$as_mkdir_p" != xfalse], [
-    MKDIR_P='mkdir -p'
-    echo "use 'mkdir -p' as MKDIR_P"
-  ], [
-    AC_MSG_ERROR([mkdir -p is required])
-  ])
+
+AS_CASE(["$target_os"],[openbsd*],[
+    ac_cv_path_mkdir="mkdir"
 ])
-MAKEDIRS="$MKDIR_P"
-AC_SUBST(MAKEDIRS)
+
+RUBY_PROG_MAKEDIRS
 
 AC_CHECK_PROG([DTRACE], [${ac_tool_prefix}dtrace], [${ac_tool_prefix}dtrace])
 AS_IF([test "$cross_compiling:$ac_cv_prog_DTRACE" = no: -a -n "$ac_tool_prefix"], [
@@ -506,11 +533,16 @@ AS_IF([test "$cross_compiling:$ac_cv_prog_DTRACE" = no: -a -n "$ac_tool_prefix"]
 AC_CHECK_PROGS(DOT, dot)
 AC_CHECK_PROGS(DOXYGEN, doxygen)
 
-for prog in ${ac_tool_prefix:+${ac_tool_prefix}pkg-config} pkg-config; do
-    AC_CHECK_PROG(PKG_CONFIG, $prog, [$prog], [], [],
-        [`"$as_dir/$ac_word$ac_exec_ext" --print-errors --version > /dev/null 2>&1 || echo "$as_dir/$ac_word$ac_exec_ext"`])
-    test -z "${PKG_CONFIG}" || break
-done
+tool_warned=$ac_tool_warned ac_tool_warned=no
+AC_CHECK_TOOL(PKG_CONFIG, pkg-config)
+ac_tool_warned=$tool_warned
+AS_IF([test -z "$PKG_CONFIG"], [],
+["$PKG_CONFIG" --print-errors --version > /dev/null 2>&1], [],
+[
+    unset ac_cv_prog_PKG_CONFIG
+    PKG_CONFIG=
+    AC_MSG_WARN([$PKG_CONFIG does not work; ignore])
+])
 
 AC_MSG_CHECKING([whether it is Android])
 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
@@ -593,22 +625,39 @@ RUBY_WERROR_FLAG([
     cd .. && rm -fr tmp.$$.try_link
 ])
 
-: ${RPATHFLAG=''}
-rpathflag=''
-AS_IF([test x"${RPATHFLAG}" = x], [
-    AS_CASE(["$target_os"],
+: "rpath" && {
+    AC_CACHE_CHECK(whether ELF binaries are produced, rb_cv_binary_elf,
+        [AC_LINK_IFELSE([AC_LANG_PROGRAM([[]], [[]])],[
+            AS_CASE(["`head -1 conftest$EXEEXT | tr -dc '\177ELF' | tr '\177' .`"],
+            [.ELF*], [rb_cv_binary_elf=yes], [rb_cv_binary_elf=no])],
+            [rb_cv_binary_elf=no])])
+
+    rpathflag=''
+    AS_IF([test x"${RPATHFLAG=}" = x], [
+	AS_CASE(["$target_os"],
 	[aix*], [rpathflag='-blibpath:'],
-	[for rpathflag in -R "-rpath "; do
+	[for rpathflag in "-rpath " -R; do
 	    AS_CASE("$rpathflag",
 		    [*" "], [AS_CASE(["${linker_flag}"],
 				     [*,], [rpathflag=`echo "$rpathflag" | tr ' ' ,`])])
 	    rpathflag="${linker_flag}${rpathflag}"
 	    RUBY_TRY_LDFLAGS([${rpathflag}.], [], [rpathflag=])
-	    AS_IF([test "x${rpathflag}" != x], [])
+	    AS_IF([test "x${rpathflag}" != x], [break])
         done])
-], [
-    rpathflag=`echo "$RPATHFLAG" | sed 's/%.*//'`
-])
+    ], [
+        rpathflag=`echo "$RPATHFLAG" | sed 's/%.*//'`
+    ])
+
+    AC_ARG_ENABLE(rpath,
+        AS_HELP_STRING([--enable-rpath], [embed run path into extension libraries.
+        enabled by default on ELF platforms]),
+        [enable_rpath=$enableval], [enable_rpath="$rb_cv_binary_elf"])
+
+    AS_IF([test "$enable_rpath:${RPATHFLAG}" = yes:], [
+        RPATHFLAG="${rpathflag:+ ${rpathflag}%1\$-s}"
+    ])
+    AS_CASE([${RPATHFLAG}],[*'%1$'*],[: ${LIBPATHFLAG=' -L%1$-s'}],[: ${LIBPATHFLAG=' -L%s'}])
+}
 
 RUBY_TRY_LDFLAGS(-fdeclspec, [fdeclspec=yes], [fdeclspec=no])
 AS_IF([test "$fdeclspec" = yes], [
@@ -621,9 +670,13 @@ AS_IF([test "$fdeclspec" = yes], [
     RUBY_APPEND_OPTIONS(CXXFLAGS, -fdeclspec)
 ])
 
-AS_CASE([$RUBY_PATCHLEVEL], [-*],
-	[RUBY_DEVEL=yes], [RUBY_DEVEL=no])
-particular_werror_flags=$RUBY_DEVEL
+AC_ARG_ENABLE(devel,
+    AS_HELP_STRING([--enable-devel], [enable development build]),
+    [RUBY_DEVEL=$enableval],
+    [AS_IF([test "x${RUBY_DEVEL-no}" != xyes], [RUBY_DEVEL=])]
+)dnl
+AC_SUBST(RUBY_DEVEL)
+particular_werror_flags=${RUBY_DEVEL:-no}
 AC_ARG_ENABLE(werror,
 	AS_HELP_STRING([--disable-werror],
 		       [don't make warnings into errors
@@ -634,10 +687,7 @@ AC_ARG_ENABLE(werror,
 rb_cv_warnflags="$warnflags"
 AS_CASE(["$GCC:${warnflags+set}:${extra_warnflags:+set}:"],
 [yes::*|yes:*:set:], [# GCC && (!warnflags || extra_warnflags)
-    AS_IF([test $gcc_major -ge 4], [
-	extra_warnflags="$extra_warnflags -Werror=extra-tokens"
-    ])
-    AS_IF([test $gcc_major -ge 5 -a $gcc_major -le 6], [
+    AS_IF([test $gcc_major -le 6], [
 	extra_warnflags="$extra_warnflags -Wno-maybe-uninitialized"
     ])
     # ICC doesn't support -Werror=
@@ -645,6 +695,7 @@ AS_CASE(["$GCC:${warnflags+set}:${extra_warnflags:+set}:"],
 	particular_werror_flags=no
     ])
     for wflag in \
+		 -Werror=extra-tokens \
 		 -Werror=deprecated-declarations \
 		 -Werror=division-by-zero -Werror=div-by-zero \
 		 -Werror=duplicated-cond \
@@ -749,7 +800,8 @@ AS_IF([test "$GCC" = yes], [
 				 [disable -D_FORTIFY_SOURCE=2 option, which causes link error on mingw]),
 		  [fortify_source=$enableval])
     AS_IF([test "x$fortify_source" != xno], [
-        RUBY_TRY_CFLAGS([$optflags -D_FORTIFY_SOURCE=2], [RUBY_APPEND_OPTION(XCFLAGS, -D_FORTIFY_SOURCE=2)], [],
+        RUBY_TRY_CFLAGS([$optflags -D_FORTIFY_SOURCE=2],
+                        [RUBY_APPEND_OPTION(XCFLAGS, -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2)], [],
                         [@%:@include <stdio.h>])
     ])
 
@@ -757,7 +809,7 @@ AS_IF([test "$GCC" = yes], [
 
     # -fstack-protector
     AS_CASE(["$target_os"],
-    [mingw*|emscripten*|wasi*], [
+    [emscripten*|wasi*], [
 	stack_protector=no
     ])
     AS_IF([test -z "${stack_protector+set}"], [
@@ -769,12 +821,25 @@ AS_IF([test "$GCC" = yes], [
 	    AS_IF([test "x$stack_protector" = xyes], [stack_protector=option; break])
 	])
     ])
+    AC_MSG_CHECKING([for -fstack-protector])
+    AC_MSG_RESULT(["$stack_protector"])
     AS_CASE(["$stack_protector"], [-*], [
 	RUBY_APPEND_OPTION(XCFLAGS, $stack_protector)
 	RUBY_APPEND_OPTION(XLDFLAGS, $stack_protector)
 	RUBY_APPEND_OPTION(LDFLAGS, $stack_protector)
     ])
 
+    # aarch64 branch protection
+    AS_CASE(["$target_cpu"], [aarch64], [
+	AS_FOR(option, opt, [-mbranch-protection=pac-ret -msign-return-address=all], [
+            RUBY_TRY_CFLAGS(option, [branch_protection=yes], [branch_protection=no])
+            AS_IF([test "x$branch_protection" = xyes], [
+                RUBY_APPEND_OPTION(XCFLAGS, option)
+                break
+            ])
+        ])
+    ])
+
     AS_CASE("${compress_debug_sections:-zlib}",
     [none|no], [], [
     RUBY_TRY_LDFLAGS(${linker_flag}--compress-debug-sections=${compress_debug_sections:-zlib},
@@ -823,33 +888,6 @@ AS_IF([test "$GCC" = yes], [
       # need lgamma_r()
     ])
 
-    # ANSI (no XCFLAGS because this is C only)
-    AS_CASE(["$target_os"],
-    [solaris*], [
-      # Because "-std=gnu99" affects existence of functions on Solaris,
-      # "-std=gnu99" will be appended to CPPFLAGS.
-	for ansi_options in -std=gnu99; do
-	    RUBY_TRY_CFLAGS(${ansi_options}, [
-		RUBY_APPEND_OPTIONS(CPPFLAGS, ${ansi_options})
-	    ], [ansi_options=])
-	    test "x${ansi_options}" = x || break
-	done
-    ],
-    [
-      # ANSI (no XCFLAGS because this is C only)
-      rb_tmp_std_check=`echo $CC $CFLAGS $optflags $warnflags $debugflags | fgrep std= | tr -d  '\015'`
-      AS_IF([test "x$rb_tmp_std_check" = "x"],
-      [
-	for ansi_options in -std=gnu99; do
-	    RUBY_TRY_CFLAGS(${ansi_options}, [
-		RUBY_APPEND_OPTIONS(warnflags, ${ansi_options})
-		RUBY_APPEND_OPTIONS(strict_warnflags, ${ansi_options})
-	    ], [ansi_options=])
-	    test "x${ansi_options}" = x || break
-	done
-      ])
-    ])
-
     # suppress annoying -Wstrict-overflow warnings
     RUBY_TRY_CFLAGS(-fno-strict-overflow, [RUBY_APPEND_OPTION(XCFLAGS, -fno-strict-overflow)])
 
@@ -858,15 +896,12 @@ AS_IF([test "$GCC" = yes], [
     test "${debugflags+set}" || {RUBY_TRY_CFLAGS(-g3, [debugflags=-g3])}
 ])
 test $ac_cv_prog_cc_g = yes && : ${debugflags=-g}
-AS_IF([test "x$RUBY_DEVEL" = xyes], [RUBY_APPEND_OPTION(XCFLAGS, -DRUBY_DEVEL=1)])
 
 AS_IF([test "$GCC" = ""], [
     AS_CASE(["$target_os"],[aix*],[warnflags="$warnflags -qinfo=por" rb_cv_warnflags="$rb_cv_warnflags -qinfo=por"])
 ])
 AS_IF([test "$GCC" = yes], [
-    AS_IF([test "$gcc_major" -ge 4], [
-	RUBY_TRY_CFLAGS(-fvisibility=hidden, [visibility_option=yes], [visibility_option=no])
-    ])
+    RUBY_TRY_CFLAGS(-fvisibility=hidden, [visibility_option=yes], [visibility_option=no])
     AC_SUBST(WERRORFLAG, "-Werror")
     AS_IF([test "$visibility_option" = yes], [
 	RUBY_APPEND_OPTION(XCFLAGS, -fvisibility=hidden)
@@ -915,17 +950,35 @@ AS_CASE(["$target_cpu"], [[i[3-6]86*]], [
     AS_IF([test "$rb_cv_gcc_compiler_cas" = i486], [ARCH_FLAG="-march=i486"])
 ])
 
+OPT_DIR=
+AC_ARG_WITH([gmp-dir],
+  AS_HELP_STRING([--with-gmp-dir=DIR],
+                 [specify the prefix directory where gmp is installed]),
+  [OPT_DIR="${OPT_DIR:+$OPT_DIR$PATH_SEPARATOR}$withval"], [])
+AC_ARG_WITH([gmp],
+  [AS_HELP_STRING([--without-gmp],
+                  [disable GNU GMP to accelerate Bignum operations])],
+  [], [with_gmp=yes])
+
 AC_ARG_WITH(opt-dir,
 	AS_HELP_STRING([--with-opt-dir=DIR-LIST],
 		       [add optional headers and libraries directories separated by $PATH_SEPARATOR]),
-	[
-		val=`echo "$PATH_SEPARATOR$withval" | sed "s|$PATH_SEPARATOR\([[^$PATH_SEPARATOR]*]\)| -I\1/include|g;s/^ //"`
-		CPPFLAGS="$CPPFLAGS $val"
-		val=`echo "$PATH_SEPARATOR$withval" | sed "s|$PATH_SEPARATOR\([[^$PATH_SEPARATOR]*]\)| -L\1/lib${rpathflag:+ $rpathflag\\\\1/lib}|g;s/^ //"`
-		LDFLAGS="$LDFLAGS $val"
-		LDFLAGS_OPTDIR="$val"
-		OPT_DIR="$withval"
-	], [OPT_DIR=])
+	[OPT_DIR="${OPT_DIR:+$OPT_DIR$PATH_SEPARATOR}$withval"], [])
+
+AS_IF([test "x$OPT_DIR" != x], [
+    val=`IFS="$PATH_SEPARATOR"
+        for dir in $OPT_DIR; do
+            test -z "$dir" && continue
+            echo x ${LIBPATHFLAG} ${RPATHFLAG} |
+            sed "s/^x *//;s${IFS}"'%1\\$-s'"${IFS}${dir}/lib${IFS}g;s${IFS}%s${IFS}${dir}/lib${IFS}g"
+        done | tr '\012' ' ' | sed 's/ *$//'`
+    LDFLAGS="${LDFLAGS:+$LDFLAGS }$val"
+    DLDFLAGS="${DLDFLAGS:+$DLDFLAGS }$val"
+    LDFLAGS_OPTDIR="$val"
+    INCFLAGS="${INCFLAGS:+$INCFLAGS }"`echo "$OPT_DIR" | tr "${PATH_SEPARATOR}" '\012' |
+        sed '/^$/d;s|^|-I|;s|$|/include|' | tr '\012' ' ' | sed 's/ *$//'`
+])
+AC_SUBST(incflags, "$INCFLAGS")
 
 test -z "${ac_env_CFLAGS_set}" -a -n "${cflags+set}" && eval CFLAGS="\"$cflags $ARCH_FLAG\""
 test -z "${ac_env_CXXFLAGS_set}" -a -n "${cxxflags+set}" && eval CXXFLAGS="\"$cxxflags $ARCH_FLAG\""
@@ -950,26 +1003,7 @@ AS_CASE(["$target_os"],
   RUBY_APPEND_OPTION(CPPFLAGS, -D__MINGW_USE_VC2005_COMPAT)
 ])
 
-AS_CASE(["$target_os"],
-[freebsd*], [
-  AC_CACHE_CHECK([whether pthread should be enabled by default],
-    rb_cv_enable_pthread_default,
-    [AC_PREPROC_IFELSE([AC_LANG_SOURCE([[
-#include <osreldate.h>
-#if __FreeBSD_version < 502102
-#error pthread should be disabled on this platform
-#endif
-      ]])],
-      rb_cv_enable_pthread_default=yes,
-      rb_cv_enable_pthread_default=no)])
-  enable_pthread=$rb_cv_enable_pthread_default
-  ],
-[mingw*], [
-  enable_pthread=no
-  ],
-[
-  enable_pthread=yes
-  ])
+RUBY_THREAD
 
 dnl Checks for libraries.
 AS_CASE(["$target_os"],[*bsd*|dragonfly*],[],[ac_cv_func_daemon=no])
@@ -1007,18 +1041,11 @@ AS_CASE(["$target_os"],
 		])
 		ac_cv_func_getcontext=no
 		ac_cv_func_setcontext=no
-		incs=`$CC -v -E -xc - < /dev/null 2>&1 | sed ['1,/^@%:@include </d;s/^ *//;s|[^./][^/]*/\.\./||g;/\/include$/!d;s||/lib|;/\/usr\/lib/d']`
-		for d in `$CC -print-search-dirs | sed -e '/^libraries: */!d;s///' | tr : '\012' | fgrep -v /../ | sed -n 's|^\(/.*/lib\)/$|\1|p'`; do
-		    incs=`echo "$incs" | fgrep -v "$d"`
-		done
-		for d in $incs; do
-		    test -d "$d" && RUBY_APPEND_OPTIONS(LDFLAGS, "-L$d")
-		done
 		ac_cv_type_getgroups=gid_t # getgroups() on Rosetta fills garbage
 		ac_cv_lib_crypt_crypt=no
 		ac_cv_func_fdatasync=no # Mac OS X wrongly reports it has fdatasync()
 		ac_cv_func_vfork=no
-		AS_IF([test $gcc_major -lt 4 -o \( $gcc_major -eq 4 -a $gcc_minor -lt 3 \)], [
+		AS_IF([test $gcc_major -eq 4 -a $gcc_minor -lt 3], [
 		    ac_cv_func___builtin_setjmp=no
 		])
 		with_setjmp_type=sigsetjmp # to hijack SIGCHLD handler
@@ -1170,22 +1197,18 @@ main()
 		ac_cv_func_getpgrp_void=no
 		ac_cv_func_memcmp_working=yes
 		ac_cv_lib_dl_dlopen=no
-		rb_cv_binary_elf=no
 		rb_cv_negative_time_t=yes
 		ac_cv_func_fcntl=yes
 		ac_cv_func_flock=yes
 		ac_cv_func_gmtime_r=yes
 		rb_cv_large_fd_select=yes
 		ac_cv_type_struct_timeval=yes
-                ac_cv_func_clock_gettime=yes
-                ac_cv_func_clock_getres=yes
 		ac_cv_func_malloc_usable_size=no
 		ac_cv_type_off_t=yes
 		ac_cv_sizeof_off_t=8
 		AS_IF([test "$target_cpu" = x64], [
 		    ac_cv_func___builtin_setjmp=yes
 		    ac_cv_func_round=no
-		    coroutine_type=yes
 		])
 		ac_cv_func_tgamma=no
 		AC_CHECK_TYPE([NET_LUID], [], [],
@@ -1274,6 +1297,11 @@ dnl AC_HEADER_STDC has been checked in AC_USE_SYSTEM_EXTENSIONS
 AC_HEADER_STDBOOL
 AC_HEADER_SYS_WAIT
 
+AC_CHECK_HEADERS([afunix.h], [], [],
+[#ifdef _WIN32
+# include <winsock2.h>
+#endif
+])
 AC_CHECK_HEADERS(atomic.h)
 AC_CHECK_HEADERS(copyfile.h)
 AC_CHECK_HEADERS(direct.h)
@@ -1320,16 +1348,13 @@ AC_CHECK_HEADERS(syscall.h)
 AC_CHECK_HEADERS(time.h)
 AC_CHECK_HEADERS(ucontext.h)
 AC_CHECK_HEADERS(utime.h)
+AC_CHECK_HEADERS(stdatomic.h)
+
 AS_CASE("$target_cpu", [x64|x86_64|i[3-6]86*], [
   AC_CHECK_HEADERS(x86intrin.h)
 ])
 RUBY_UNIVERSAL_CHECK_HEADER([x86_64, i386], x86intrin.h)
 
-AC_ARG_WITH([gmp],
-  [AS_HELP_STRING([--without-gmp],
-    [disable GNU GMP to accelerate Bignum operations])],
-  [],
-  [with_gmp=yes])
 AS_IF([test "x$with_gmp" != xno],
   [AC_CHECK_HEADERS(gmp.h)
    AS_IF([test "x$ac_cv_header_gmp_h" != xno],
@@ -1341,6 +1366,8 @@ AC_ARG_WITH([jemalloc],
   [with_jemalloc=$withval], [with_jemalloc=no])
 AS_IF([test "x$with_jemalloc" != xno],[
   # find jemalloc header first
+  save_CPPFLAGS="${CPPFLAGS}"
+  CPPFLAGS="${INCFLAGS} ${CPPFLAGS}"
   malloc_header=
   AC_CHECK_HEADER(jemalloc/jemalloc.h, [malloc_header=jemalloc/jemalloc.h], [
     AC_CHECK_HEADER(jemalloc.h, [malloc_header=jemalloc.h])
@@ -1372,6 +1399,8 @@ AS_IF([test "x$with_jemalloc" != xno],[
       done
     done
   ])
+  CPPFLAGS="${save_CPPFLAGS}"
+  unset save_CPPFLAGS
   with_jemalloc=${rb_cv_jemalloc_library}
   AS_CASE(["$with_jemalloc"],
   [no],
@@ -1892,7 +1921,7 @@ AS_IF([test $rb_cv_stack_end_address != no], [
 dnl Checks for library functions.
 AC_TYPE_GETGROUPS
 AS_CASE(["${target_cpu}-${target_os}:${target_archs}"],
-[powerpc-darwin*], [
+[powerpc*-darwin*], [
   AC_LIBSOURCES(alloca.c)
   AC_SUBST([ALLOCA], [\${LIBOBJDIR}alloca.${ac_objext}])
   AC_DEFINE(C_ALLOCA)
@@ -1901,8 +1930,8 @@ AS_CASE(["${target_cpu}-${target_os}:${target_archs}"],
 [universal-darwin*:*ppc*], [
   AC_LIBSOURCES(alloca.c)
   AC_SUBST([ALLOCA], [\${LIBOBJDIR}alloca.${ac_objext}])
-  RUBY_DEFINE_IF([defined __powerpc__], C_ALLOCA, 1)
-  RUBY_DEFINE_IF([defined __powerpc__], alloca, alloca)
+  RUBY_DEFINE_IF([defined __POWERPC__], C_ALLOCA, 1) # Darwin defines __POWERPC__ for ppc and ppc64 both
+  RUBY_DEFINE_IF([defined __POWERPC__], alloca, alloca)
   ],
 [
   AC_FUNC_ALLOCA
@@ -1982,6 +2011,7 @@ AC_CHECK_FUNCS(_longjmp)		# used for AC_ARG_WITH(setjmp-type)
 test x$ac_cv_func__longjmp = xno && ac_cv_func__setjmp=no
 AC_CHECK_FUNCS(arc4random_buf)
 AC_CHECK_FUNCS(atan2l atan2f)
+AC_CHECK_DECLS(atomic_signal_fence, [], [], [#include <stdatomic.h>])
 AC_CHECK_FUNCS(chmod)
 AC_CHECK_FUNCS(chown)
 AC_CHECK_FUNCS(chroot)
@@ -2572,6 +2602,15 @@ AS_CASE([$coroutine_type], [yes|''], [
         [arm64-darwin*], [
             coroutine_type=arm64
         ],
+        # Correct target name is powerpc*-, but Ruby seems to prefer ppc*-.
+        # Notice that Darwin PPC ABI differs from AIX and ELF.
+        # Adding PPC targets for AIX, *BSD and *Linux will require separate implementations.
+        [powerpc-darwin*|ppc-darwin*], [
+            coroutine_type=ppc
+        ],
+        [powerpc64-darwin*|ppc64-darwin*], [
+            coroutine_type=ppc64
+        ],
         [x*64-linux*], [
             AS_CASE(["$ac_cv_sizeof_voidp"],
                 [8], [ coroutine_type=amd64 ],
@@ -2659,25 +2698,7 @@ AC_DEFINE_UNQUOTED(COROUTINE_H, ["$COROUTINE_H"])
 AC_SUBST(X_COROUTINE_H, [$COROUTINE_H])
 AC_SUBST(X_COROUTINE_SRC, [$COROUTINE_SRC])
 
-AS_IF([test x"$enable_pthread" = xyes], [
-    for pthread_lib in thr pthread pthreads c c_r root; do
-	AC_CHECK_LIB($pthread_lib, pthread_create,
-		     rb_with_pthread=yes, rb_with_pthread=no)
-	AS_IF([test "$rb_with_pthread" = "yes"], [break])
-    done
-    AS_IF([test x"$rb_with_pthread" = xyes], [
-	AC_DEFINE(_REENTRANT)
-	AC_DEFINE(_THREAD_SAFE)
-	AC_DEFINE(HAVE_LIBPTHREAD)
-	AC_CHECK_HEADERS(pthread_np.h, [], [], [@%:@include <pthread.h>])
-	AS_CASE(["$pthread_lib:$target_os"],
-		[c:*], [],
-		[root:*], [],
-		[c_r:*|*:openbsd*|*:mirbsd*],  [LIBS="-pthread $LIBS"],
-		[LIBS="-l$pthread_lib $LIBS"])
-    ], [
-	AC_MSG_WARN("Don't know how to find pthread library on your system -- thread support disabled")
-    ])
+AS_IF([test "$THREAD_MODEL" = pthread], [
     AC_CACHE_CHECK([whether pthread_t is scalar type], [rb_cv_scalar_pthread_t], [
 	AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
 	    @%:@include <pthread.h>
@@ -2766,12 +2787,12 @@ AS_IF([test x"$ac_cv_header_ucontext_h" = xyes -o x"$rb_cv_ucontext_in_signal_h"
     ], [
 	AC_DEFINE_UNQUOTED(DEFINE_MCONTEXT_PTR(mc, uc), mcontext_t *mc = &(uc)->uc_mcontext)
     ])
-    AS_IF([test x"$rb_with_pthread" = xyes], [
+    AS_IF([test x"$THREAD_MODEL" = xpthread], [
 	AC_CHECK_FUNCS(getcontext setcontext)
     ])
 ])
 
-AS_IF([test "$ac_cv_func_fork_works" = "yes" -a "$rb_with_pthread" = "yes"], [
+AS_IF([test "$ac_cv_func_fork_works" = "yes" -a x"$THREAD_MODEL" = xpthread], [
     AC_CACHE_CHECK([if fork works with pthread], rb_cv_fork_with_pthread,
 	[AC_RUN_IFELSE([AC_LANG_SOURCE([[
 #include <stdlib.h>
@@ -2893,12 +2914,6 @@ AC_ARG_WITH(dln-a-out,
 	])
 ])
 
-AC_CACHE_CHECK(whether ELF binaries are produced, rb_cv_binary_elf,
-[AC_LINK_IFELSE([AC_LANG_PROGRAM([[]], [[]])],[
-AS_CASE(["`head -1 conftest$EXEEXT | tr -dc '\177ELF' | tr '\177' .`"],
-[.ELF*], [rb_cv_binary_elf=yes], [rb_cv_binary_elf=no])],
-rb_cv_binary_elf=no)])
-
 AS_IF([test "$rb_cv_binary_elf" = yes], [
   AC_DEFINE(USE_ELF)
   AC_CHECK_HEADERS([elf.h elf_abi.h])
@@ -2975,13 +2990,25 @@ STATIC=
   ])
 }
 
-: "rpath" && {
-  AC_ARG_ENABLE(rpath,
-       AS_HELP_STRING([--enable-rpath], [embed run path into extension libraries.
-       enabled by default on ELF platforms]),
-       [enable_rpath=$enableval], [enable_rpath="$rb_cv_binary_elf"])
+EXTSTATIC=
+AC_SUBST(EXTSTATIC)dnl
+AC_ARG_WITH(static-linked-ext,
+	    AS_HELP_STRING([--with-static-linked-ext], [link external modules statically]),
+            [AS_CASE([$withval],[yes],[STATIC=;EXTSTATIC=static],[no],[],[EXTSTATIC="$withval"])])
+AS_CASE([",$EXTSTATIC,"], [,static,|*,enc,*], [
+  ENCOBJS='enc/encinit.$(OBJEXT) enc/libenc.$(LIBEXT) enc/libtrans.$(LIBEXT)'
+  EXTOBJS='ext/extinit.$(OBJEXT)'
+  AC_DEFINE_UNQUOTED(EXTSTATIC, 1)
+  AC_SUBST(ENCSTATIC, static)
+], [
+  ENCOBJS='dmyenc.$(OBJEXT)'
+  EXTOBJS='dmyext.$(OBJEXT)'
+])
+AC_SUBST(ENCOBJS)
+AC_SUBST(EXTOBJS)
 
-  AS_CASE(["$target_os"],
+: "rpath" && {
+    AS_CASE(["$target_os"],
 	[solaris*], [	AS_IF([test "$GCC" = yes], [
 			    : ${LDSHARED='$(CC) -shared'}
 			    AS_IF([test "$rb_cv_prog_gnu_ld" = yes], [
@@ -3021,7 +3048,6 @@ STATIC=
 			rb_cv_dlopen=yes],
 	[interix*], [	: ${LDSHARED='$(CC) -shared'}
 			XLDFLAGS="$XLDFLAGS -Wl,-E"
-			LIBPATHFLAG=" -L%1\$-s"
 			rb_cv_dlopen=yes],
 	[freebsd*|dragonfly*], [
 			: ${LDSHARED='$(CC) -shared'}
@@ -3040,8 +3066,16 @@ STATIC=
 	[darwin*], [	: ${LDSHARED='$(CC) -dynamic -bundle'}
 			: ${DLDSHARED='$(CC) -dynamiclib'}
 			: ${LDFLAGS=""}
-			: ${LIBPATHENV=DYLD_FALLBACK_LIBRARY_PATH}
+			: ${LIBPATHENV=DYLD_LIBRARY_PATH}
 			: ${PRELOADENV=DYLD_INSERT_LIBRARIES}
+                        AS_IF([test x"$enable_shared" = xyes], [
+                            # Resolve symbols from libruby.dylib when --enable-shared
+                            EXTDLDFLAGS='$(LIBRUBYARG_SHARED)'
+                        ], [test "x$EXTSTATIC" = x], [
+                            # When building exts as bundles, a mach-o bundle needs to know its loader
+                            # program to bind symbols from the ruby executable
+                            EXTDLDFLAGS="-bundle_loader '\$(BUILTRUBY)'"
+			])
 			rb_cv_dlopen=yes],
         [aix*], [	: ${LDSHARED='$(CC)'}
 			AS_IF([test "$GCC" = yes], [
@@ -3073,30 +3107,35 @@ STATIC=
 	[atheos*], [	: ${LDSHARED='$(CC) -shared'}
 			rb_cv_dlopen=yes],
 	[	: ${LDSHARED='$(LD)'}])
-  AC_MSG_RESULT($rb_cv_dlopen)
+    AC_MSG_RESULT($rb_cv_dlopen)
+}
 
-  AS_IF([test "$rb_cv_dlopen" = yes], [
+AS_IF([test "$rb_cv_dlopen" = yes], [
     AS_CASE(["$target_os"],
-      [darwin*], [
+    [darwin*], [
+        AC_SUBST(ADDITIONAL_DLDFLAGS, "")
 	for flag in \
-	  "-undefined dynamic_lookup" \
 	  "-multiply_defined suppress" \
+	  "-undefined dynamic_lookup" \
 	  ; do
-	  test "x${linker_flag}" = x || flag="${linker_flag}`echo ${flag} | tr ' ' ,`"
-	  RUBY_TRY_LDFLAGS([$flag], [], [flag=])
-	  AS_IF([test "x$flag" != x], [
-	    RUBY_APPEND_OPTIONS(DLDFLAGS, [$flag])
-	  ])
+            test "x${linker_flag}" = x || flag="${linker_flag}`echo ${flag} | tr ' ' ,`"
+            RUBY_TRY_LDFLAGS([$flag], [], [flag=])
+            AS_IF([test x"$flag" = x], [continue])
+
+            AC_MSG_CHECKING([whether $flag is accepted for bundle])
+            : > conftest.c
+            AS_IF([${LDSHARED%%'$(CC)'*}$CC${LDSHARED@%:@*'$(CC)'} -o conftest.bundle $flag conftest.c >/dev/null 2>conftest.err &&
+                test ! -s conftest.err], [
+                AC_MSG_RESULT([yes])
+                RUBY_APPEND_OPTIONS(DLDFLAGS, [$flag])
+            ], [
+                AC_MSG_RESULT([no])
+                RUBY_APPEND_OPTIONS(ADDITIONAL_DLDFLAGS, [$flag])
+            ])
+            rm -fr conftest.*
 	done
-      ])
-  ])
-
-  AS_IF([test "$enable_rpath:${RPATHFLAG}" = yes:], [
-      AS_IF([test "x$rpathflag" != x], [
-	  RPATHFLAG=" ${rpathflag}%1\$-s"
-      ])
-  ])
-}
+    ])
+])
 
 AS_IF([test "${LDSHAREDXX}" = ""], [
     AS_CASE(["${LDSHARED}"],
@@ -3112,7 +3151,6 @@ AS_IF([test "${LDSHAREDXX}" = ""], [
 	[ld" "*], [
 	    ])
 ])
-AS_CASE([${RPATHFLAG}],[*'%1$'*],[: ${LIBPATHFLAG=' -L%1$-s'}],[: ${LIBPATHFLAG=' -L%s'}])
 
 AC_SUBST(LINK_SO)
 AC_SUBST(LIBPATHFLAG)
@@ -3121,23 +3159,6 @@ AC_SUBST(LIBPATHENV, "${LIBPATHENV-LD_LIBRARY_PATH}")
 AC_SUBST(PRELOADENV, "${PRELOADENV-LD_PRELOAD}")
 AC_SUBST(TRY_LINK)
 
-AS_IF([test "x$OPT_DIR" != x], [
-    pat=`echo "${LDFLAGS_OPTDIR}" | sed ['s/[][\\.*|]/\\\\&/']`
-    LDFLAGS=`echo "${LDFLAGS}" | sed "s| ${pat}||"`
-    val=`IFS="$PATH_SEPARATOR"
-        for dir in $OPT_DIR; do
-            echo x ${LIBPATHFLAG} ${RPATHFLAG} |
-            sed "s/^x *//;s${IFS}"'%1\\$-s'"${IFS}${dir}/lib${IFS}g;s${IFS}%s${IFS}${dir}/lib${IFS}g"
-        done | tr '\012' ' ' | sed 's/ *$//'`
-    AS_IF([test x"$val" != x], [
-	test x"${LDFLAGS}" = x || LDFLAGS="$LDFLAGS "
-	LDFLAGS="$LDFLAGS$val"
-	test x"${DLDFLAGS}" = x || DLDFLAGS="$DLDFLAGS "
-	DLDFLAGS="$DLDFLAGS$val"
-    ])
-    LDFLAGS_OPTDIR="$val"
-])
-
 AS_CASE(["$target_os"],
 [freebsd*], [
     AC_CHECK_LIB([procstat], [procstat_open_sysctl])
@@ -3152,6 +3173,15 @@ AS_CASE(["$target_cpu-$target_os"],
     AS_IF([test "x$ac_cv_header_execinfo_h" = xyes], [
 	AC_CHECK_LIB([execinfo], [backtrace])
 	AC_CHECK_HEADERS([libunwind.h])
+
+    AC_CHECK_HEADERS([mach/task.h mach/mach_init.h mach/mach_port.h])
+    AS_IF([ test \
+        "x${ac_cv_header_mach_task_h}" = xyes -a \
+        "x${ac_cv_header_mach_mach_init_h}" = xyes -a \
+        "x${ac_cv_header_mach_mach_port_h}" = xyes \
+    ], [
+        AC_DEFINE([HAVE_MACH_TASK_EXCEPTION_PORTS], [1])
+    ])
     ])],
 [*-freebsd*|x86_64-netbsd*], [
     AC_CHECK_HEADERS([execinfo.h])
@@ -3281,23 +3311,6 @@ AC_ARG_WITH(ext,
 AC_ARG_WITH(out-ext,
             AS_HELP_STRING([--with-out-ext=EXTS],
                            [pass to --without-ext option of extmk.rb]))
-EXTSTATIC=
-AC_SUBST(EXTSTATIC)dnl
-AC_ARG_WITH(static-linked-ext,
-	    AS_HELP_STRING([--with-static-linked-ext], [link external modules statically]),
-            [AS_CASE([$withval],[yes],[STATIC=;EXTSTATIC=static],[no],[],[EXTSTATIC="$withval"])])
-AS_CASE([",$EXTSTATIC,"], [,static,|*,enc,*], [
-  ENCOBJS='enc/encinit.$(OBJEXT) enc/libenc.$(LIBEXT) enc/libtrans.$(LIBEXT)'
-  EXTOBJS='ext/extinit.$(OBJEXT)'
-  AC_DEFINE_UNQUOTED(EXTSTATIC, 1)
-  AC_SUBST(ENCSTATIC, static)
-], [
-  ENCOBJS='dmyenc.$(OBJEXT)'
-  EXTOBJS='dmyext.$(OBJEXT)'
-])
-AC_SUBST(ENCOBJS)
-AC_SUBST(EXTOBJS)
-
 AC_ARG_WITH(setup,
 	    AS_HELP_STRING([--with-setup=SETUP], [use extension libraries setup]),
 	    [setup=$withval])
@@ -3347,7 +3360,6 @@ for var in bindir includedir libdir rubylibprefix; do
 done
 
 BTESTRUBY='$(MINIRUBY)'
-BOOTSTRAPRUBY='$(BASERUBY)'
 AS_IF([test x"$cross_compiling" = xyes], [
   test x"$MINIRUBY" = x && MINIRUBY="${RUBY-$BASERUBY} -I`$CHDIR .; pwd` "-r'$(arch)-fake'
   XRUBY_LIBDIR=`${RUBY-$BASERUBY} -rrbconfig -e ['puts RbConfig::CONFIG["libdir"]']`
@@ -3357,6 +3369,10 @@ AS_IF([test x"$cross_compiling" = xyes], [
   AC_SUBST(XRUBY_RUBYLIBDIR)
   AC_SUBST(XRUBY_RUBYHDRDIR)
   PREP='$(arch)-fake.rb'
+  AS_CASE(["$enable_shared:$EXTSTATIC:$target_os"], [no::darwin*], [
+    # darwin target requires miniruby for linking ext bundles
+    PREP="$PREP"' miniruby$(EXEEXT)'
+  ])
   RUNRUBY_COMMAND='$(MINIRUBY) -I`cd $(srcdir)/lib; pwd`'
   RUNRUBY='$(RUNRUBY_COMMAND)'
   XRUBY='$(MINIRUBY)'
@@ -3370,7 +3386,6 @@ AS_IF([test x"$cross_compiling" = xyes], [
   RUNRUBY_COMMAND='$(MINIRUBY) $(tooldir)/runruby.rb --extout=$(EXTOUT) $(RUNRUBYOPT)'
   RUNRUBY='$(RUNRUBY_COMMAND) --'
   XRUBY='$(RUNRUBY)'
-  AS_CASE(["$HAVE_BASERUBY:$build_os"], [no:*|*:mingw*], [BOOTSTRAPRUBY='$(MINIRUBY)'])
   TEST_RUNNABLE=yes
   CROSS_COMPILING=no
 ])
@@ -3382,7 +3397,6 @@ AC_SUBST(PREP)
 AC_SUBST(RUNRUBY_COMMAND)
 AC_SUBST(RUNRUBY)
 AC_SUBST(XRUBY)
-AC_SUBST(BOOTSTRAPRUBY)
 AC_SUBST(EXTOUT, [${EXTOUT=.ext}])
 
 FIRSTMAKEFILE=""
@@ -3621,7 +3635,7 @@ AS_CASE("$cross_compiling:${LIBPATHENV}", [yes:* | no:], [], [
     AC_MSG_CHECKING(whether wrapper for $LIBPATHENV is needed)
     AS_IF([env ${LIBPATHENV}=/lib /bin/sh -c ': ${'${LIBPATHENV}'?}' 2>/dev/null],
 	[AC_MSG_RESULT(no)],
-	[PREP="$PREP"' exe/$(PROGRAM)'
+	[AC_SUBST(XRUBY_LIBPATHENV_WRAPPER, 'exe/$(PROGRAM)')
 	AC_MSG_RESULT(yes)]
     )
 ])
@@ -3736,12 +3750,12 @@ AS_CASE(["$RDOCTARGET:$CAPITARGET"],[nodoc:nodoc],[INSTALLDOC=nodoc],[INSTALLDOC
 AC_SUBST(INSTALLDOC)
 
 AC_ARG_ENABLE(jit-support,
-        AS_HELP_STRING([--disable-jit-support], [disable JIT features]),
-        [MJIT_SUPPORT=$enableval],
-        # Enable mjit by default except for WASI
-        [AS_IF([test x"$target_os" != "xwasi"],
-		[MJIT_SUPPORT=yes],
-		[MJIT_SUPPORT=no ])])
+    AS_HELP_STRING([--disable-jit-support], [disable JIT features]),
+    [MJIT_SUPPORT=$enableval],
+    [AS_CASE(["$target_os"],
+        [wasi | mingw* | solaris*], [MJIT_SUPPORT=no],
+        [MJIT_SUPPORT=yes]
+    )])
 
 AS_IF([test x"$MJIT_SUPPORT" = "xyes"],
 	[AC_DEFINE(USE_MJIT, 1)],
@@ -3749,6 +3763,116 @@ AS_IF([test x"$MJIT_SUPPORT" = "xyes"],
 
 AC_SUBST(MJIT_SUPPORT)
 
+AC_CHECK_PROG(RUSTC, [rustc], [rustc], [no]) dnl no ac_tool_prefix
+
+dnl check if rustc is recent enough to build YJIT (rustc >= 1.58.0)
+YJIT_RUSTC_OK=no
+AS_IF([test "$RUSTC" != "no"],
+    AC_MSG_CHECKING([whether ${RUSTC} works for YJIT])
+    YJIT_TARGET_ARCH=
+    AS_CASE(["$target_cpu"],
+        [arm64|aarch64], [YJIT_TARGET_ARCH=aarch64],
+        [x86_64], [YJIT_TARGET_ARCH=x86_64],
+    )
+    dnl Fails in case rustc target doesn't match ruby target.
+    dnl Can happen on Rosetta, for example.
+    AS_IF([echo "#[cfg(target_arch = \"$YJIT_TARGET_ARCH\")] fn main() { let x = 1; format!(\"{x}\"); }" |
+            $RUSTC - --emit asm=/dev/null 2>/dev/null],
+        [YJIT_RUSTC_OK=yes]
+    )
+    AC_MSG_RESULT($YJIT_RUSTC_OK)
+)
+
+dnl check if we can build YJIT on this target platform
+dnl we can't easily cross-compile with rustc so we don't support that
+YJIT_TARGET_OK=no
+AS_IF([test "$cross_compiling" = no],
+    AS_CASE(["$target_cpu-$target_os"],
+        [*android*], [
+            YJIT_TARGET_OK=no
+        ],
+        [arm64-darwin*|aarch64-darwin*|x86_64-darwin*], [
+            YJIT_TARGET_OK=yes
+        ],
+        [arm64-*linux*|aarch64-*linux*|x86_64-*linux*], [
+            YJIT_TARGET_OK=yes
+        ],
+        [arm64-*bsd*|aarch64-*bsd*|x86_64-*bsd*], [
+            YJIT_TARGET_OK=yes
+        ]
+    )
+)
+
+dnl build YJIT in release mode if rustc >= 1.58.0 is present and we are on a supported platform
+AC_ARG_ENABLE(yjit,
+    AS_HELP_STRING([--enable-yjit],
+    [enable in-process JIT compiler that requires Rust build tools. enabled by default on supported platforms if rustc 1.58.0+ is available]),
+    [YJIT_SUPPORT=$enableval],
+    [AS_CASE(["$enable_jit_support:$YJIT_TARGET_OK:$YJIT_RUSTC_OK"],
+        [yes:yes:yes|:yes:yes], [
+            YJIT_SUPPORT=yes
+        ],
+        [YJIT_SUPPORT=no]
+    )]
+)
+
+CARGO=
+CARGO_BUILD_ARGS=
+YJIT_LIBS=
+AS_CASE(["${YJIT_SUPPORT}"],
+[yes|dev|stats|dev_nodebug], [
+    AS_IF([test x"$enable_jit_support" = "xno"],
+        AC_MSG_ERROR([--disable-jit-support but --enable-yjit. YJIT requires JIT support])
+    )
+    AS_IF([test x"$RUSTC" = "xno"],
+        AC_MSG_ERROR([rustc is required. Installation instructions available at https://www.rust-lang.org/tools/install])
+    )
+
+    AS_CASE(["${YJIT_SUPPORT}"],
+    [yes], [
+	rb_rust_target_subdir=release
+    ],
+    [dev], [
+	rb_rust_target_subdir=debug
+	CARGO_BUILD_ARGS='--features stats,disasm'
+	AC_DEFINE(RUBY_DEBUG, 1)
+    ],
+    [dev_nodebug], [
+	rb_rust_target_subdir=dev_nodebug
+	CARGO_BUILD_ARGS='--profile dev_nodebug --features stats,disasm'
+    ],
+    [stats], [
+	rb_rust_target_subdir=stats
+	CARGO_BUILD_ARGS='--profile stats --features stats'
+	AC_DEFINE(YJIT_STATS, 1)
+    ])
+
+    AS_IF([test -n "${CARGO_BUILD_ARGS}"], [
+             AC_CHECK_TOOL(CARGO, [cargo], [no])
+             AS_IF([test x"$CARGO" = "xno"],
+                AC_MSG_ERROR([cargo is required. Installation instructions available at https://www.rust-lang.org/tools/install])
+             ]))
+
+    YJIT_LIBS="yjit/target/${rb_rust_target_subdir}/libyjit.a"
+    AS_CASE(["$target_os"],[openbsd*],[
+        # Link libc++abi (which requires libpthread) for _Unwind_* functions needed by yjit
+        LDFLAGS="$LDFLAGS -lpthread -lc++abi"
+    ])
+    YJIT_OBJ='yjit.$(OBJEXT)'
+    AS_IF([test x"$YJIT_SUPPORT" != "xyes" ], [
+        AC_DEFINE_UNQUOTED(YJIT_SUPPORT, [$YJIT_SUPPORT])
+    ])
+    AC_DEFINE(USE_YJIT, 1)
+], [AC_DEFINE(USE_YJIT, 0)])
+
+dnl These variables end up in ::RbConfig::CONFIG
+AC_SUBST(YJIT_SUPPORT)dnl what flavor of YJIT the Ruby build includes
+AC_SUBST(RUSTC)dnl Rust compiler command
+AC_SUBST(CARGO)dnl Cargo command for Rust builds
+AC_SUBST(CARGO_BUILD_ARGS)dnl for selecting Rust build profiles
+AC_SUBST(YJIT_LIBS)dnl for optionally building the Rust parts of YJIT
+AC_SUBST(YJIT_OBJ)dnl for optionally building the C parts of YJIT
+
 AC_ARG_ENABLE(install-static-library,
 	AS_HELP_STRING([--disable-install-static-library], [do not install static ruby library]),
 	[INSTALL_STATIC_LIBRARY=$enableval
@@ -3785,13 +3909,26 @@ AS_CASE(["$target_os"],
 	],
     [darwin*], [
 	RUBY_APPEND_OPTION(CFLAGS, -pipe)
+        AC_MSG_CHECKING([whether Security framework is needed])
 	AC_COMPILE_IFELSE([
-	    AC_LANG_BOOL_COMPILE_TRY([@%:@include <AvailabilityMacros.h>],
-		[MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_7 &&
-		 MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_10])],
+	    AC_LANG_BOOL_COMPILE_TRY([
+@%:@include <AvailabilityMacros.h>
+enum {
+    least = MAC_OS_X_VERSION_10_7, /* just fail if undefined */
+    required = MAC_OS_X_VERSION_MIN_REQUIRED,
+    upper /* bigger than MIN_REQUIRED, or */
+@%:@ifdef MAC_OS_X_VERSION_10_10
+        = MAC_OS_X_VERSION_10_10
+@%:@endif
+};],
+	    [required >= least && required < upper])],
 	    [dnl
+		AC_MSG_RESULT(yes)
 		RUBY_APPEND_OPTION(XLDFLAGS, [-framework Security])
 		RUBY_APPEND_OPTION(LIBRUBYARG_STATIC, [-framework Security])
+	    ],dnl
+	    [dnl
+		AC_MSG_RESULT(no)
 	    ]dnl
 	)
 	RUBY_APPEND_OPTION(XLDFLAGS, [-framework CoreFoundation])
@@ -3859,8 +3996,6 @@ AS_CASE(["$target_os"],
 
 MINIOBJS="$MINIDLNOBJ"
 
-RUBY_THREAD
-
 AC_ARG_ENABLE(debug-env,
        AS_HELP_STRING([--enable-debug-env], [enable RUBY_DEBUG environment variable]),
        [AC_SUBST(ENABLE_DEBUG_ENV, yes)])
@@ -4001,6 +4136,7 @@ AC_SUBST(EXPORT_PREFIX)
 AC_SUBST(SYMBOL_PREFIX)
 AC_SUBST(MINIOBJS)
 AC_SUBST(THREAD_MODEL)
+AC_SUBST(COROUTINE_TYPE, ${coroutine_type})
 AC_SUBST(PLATFORM_DIR)
 
 firstmf=`echo $FIRSTMAKEFILE | sed 's/:.*//'`
@@ -4061,6 +4197,7 @@ AS_CASE(["$ruby_version"],
 AS_IF([test ${RUBY_LIB_VERSION_STYLE+set}], [
     {
     echo "#define RUBY_LIB_VERSION_STYLE $RUBY_LIB_VERSION_STYLE"
+    echo '@%:@include "confdefs.h"'
     echo '#define STRINGIZE(x) x'
     test -f revision.h -o -f "${srcdir}/revision.h" || echo '#define RUBY_REVISION 0'
     echo '#include "version.h"'
@@ -4232,6 +4369,13 @@ AS_IF([test -z "$MANTYPE"], [
 ])
 AC_SUBST(MANTYPE)
 
+MKMF_VERBOSE=0
+AC_ARG_ENABLE(mkmf-verbose,
+    AS_HELP_STRING([--enable-mkmf-verbose], [enable verbose in mkmf]),
+    [MKMF_VERBOSE=1],
+    [MKMF_VERBOSE=0])
+AC_SUBST(MKMF_VERBOSE)
+
 AC_ARG_ENABLE(rubygems,
 	AS_HELP_STRING([--disable-rubygems], [disable rubygems by default]),
 	[enable_rubygems="$enableval"], [enable_rubygems=yes])
@@ -4292,6 +4436,14 @@ AC_SUBST(XCC_WRAPPER)
 
 AS_CASE([" $CPP "], [*" $CC "*], [CPP=`echo " $CPP " | sed "s| $CC |"' $(CC) |;s/^ *//;s/  *$//'`])
 
+AS_IF([test ! -f "$srcdir/revision.h"], [
+    AS_IF([test "x$HAVE_BASERUBY" = xyes], [
+	${BASERUBY} -C "$srcdir" tool/file2lastrev.rb -q --revision.h > "$srcdir/revision.h"
+    ], [
+	touch "$srcdir/revision.h"
+    ])
+])
+
 AS_IF([test x"$firstmf" != x], [
     AC_CONFIG_FILES($firstmf:$firsttmpl, [], [firstmf="$firstmf" firsttmpl="$firsttmpl"])
 ])
@@ -4308,17 +4460,24 @@ AC_CONFIG_FILES(Makefile:template/Makefile.in, [
 	AS_CASE("$VCS",
 		['$(GIT)'|git], [VCSUP='$(VCS) pull --rebase $(GITPULLOPTIONS)'],
 		[VCSUP='$(VCS)'])
-	sed -n \
-	    -e '[/^@%:@define \(RUBY_RELEASE_[A-Z]*\) \([0-9][0-9]*\)/]{' \
-	    -e   's//\1 = \2/' \
-	    -e   '[s/ \([0-9]\)$/ 0\1/]' \
-	    -e   p \
-	    -e '}' "$srcdir/version.h"
+	for f in "$srcdir/version.h" "$srcdir/revision.h"; do
+            test -f "$f" || continue
+	    sed -n \
+	        -e '[/^@%:@define \(RUBY_RELEASE_[A-Z]*\) \([0-9][0-9]*\)/]{' \
+	        -e   's//\1 = \2/' \
+	        -e   '[s/ \([0-9]\)$/ 0\1/]' \
+	        -e   p \
+	        -e '}' "$f"
+        done
 	sed '/^MISSING/s/\$U\././g;/^VCS *=/s#@VCS@#'"$VCS"'#;/^VCSUP *=/s#@VCSUP@#'"$VCSUP"'#' Makefile
 	echo; test x"$EXEEXT" = x || echo 'miniruby: miniruby$(EXEEXT)'
 	AS_IF([test "$gnumake" != yes], [
 	    echo ['$(MKFILES): $(srcdir)/common.mk']
 	    sed ['s/{\$([^(){}]*)[^{}]*}//g'] ${srcdir}/common.mk
+            AS_IF([test "$YJIT_SUPPORT" = yes], [
+                cat ${srcdir}/yjit/not_gmake.mk
+                echo ['$(MKFILES): ${srcdir}/yjit/not_gmake.mk']
+            ])
 	], [
 	    echo 'distclean-local::; @$(RM) GNUmakefile uncommon.mk'
 	])
@@ -4336,7 +4495,7 @@ AC_CONFIG_FILES(Makefile:template/Makefile.in, [
 	echo 'ruby: $(PROGRAM);' >> $tmpmk
 	test "$tmpmk" = "$tmpgmk" || rm -f "$tmpgmk"
     ]) && mv -f $tmpmk Makefile],
-[EXEEXT='$EXEEXT' MAKE='${MAKE-make}' gnumake='$gnumake' GIT='$GIT'])
+[EXEEXT='$EXEEXT' MAKE='${MAKE-make}' gnumake='$gnumake' GIT='$GIT' YJIT_SUPPORT='$YJIT_SUPPORT'])
 
 AC_ARG_WITH([ruby-pc],
 	    AS_HELP_STRING([--with-ruby-pc=FILENAME], [pc file basename]),
@@ -4387,7 +4546,7 @@ config_summary "site libraries path" "$rubysitearchprefix"
 config_summary "vendor path"         "$vendordir"
 config_summary "target OS"           "$target_os"
 config_summary "compiler"            "$CC"
-config_summary "with pthread"        "$enable_pthread"
+config_summary "with thread"         "$THREAD_MODEL"
 config_summary "with coroutine"      "$coroutine_type"
 config_summary "enable shared libs"  "$ENABLE_SHARED"
 config_summary "dynamic library ext" "$DLEXT"
@@ -4400,7 +4559,8 @@ config_summary "debugflags"          "$debugflags"
 config_summary "warnflags"           "$warnflags"
 config_summary "strip command"       "$STRIP"
 config_summary "install doc"         "$DOCTARGETS"
-config_summary "JIT support"         "$MJIT_SUPPORT"
+config_summary "MJIT support"        "$MJIT_SUPPORT"
+config_summary "YJIT support"        "$YJIT_SUPPORT"
 config_summary "man page type"       "$MANTYPE"
 config_summary "search path"         "$search_path"
 config_summary "static-linked-ext"   ${EXTSTATIC:+"yes"}
diff --git a/cont.c b/cont.c
index ee7b856bb1..5375d1945b 100644
--- a/cont.c
+++ b/cont.c
@@ -29,11 +29,15 @@ extern int madvise(caddr_t, size_t, int);
 #include "gc.h"
 #include "internal.h"
 #include "internal/cont.h"
+#include "internal/error.h"
 #include "internal/proc.h"
+#include "internal/sanitizers.h"
 #include "internal/warnings.h"
 #include "ruby/fiber/scheduler.h"
 #include "mjit.h"
+#include "yjit.h"
 #include "vm_core.h"
+#include "vm_sync.h"
 #include "id_table.h"
 #include "ractor_core.h"
 
@@ -66,6 +70,8 @@ static VALUE rb_cFiberPool;
 #define FIBER_POOL_ALLOCATION_FREE
 #endif
 
+#define jit_cont_enabled (mjit_enabled || rb_yjit_enabled_p())
+
 enum context_type {
     CONTINUATION_CONTEXT = 0,
     FIBER_CONTEXT = 1
@@ -194,6 +200,15 @@ struct fiber_pool {
     size_t vm_stack_size;
 };
 
+// Continuation contexts used by JITs
+struct rb_jit_cont {
+    rb_execution_context_t *ec; // continuation ec
+    struct rb_jit_cont *prev, *next; // used to form lists
+};
+
+// Doubly linked list for enumerating all on-stack ISEQs.
+static struct rb_jit_cont *first_jit_cont;
+
 typedef struct rb_context_struct {
     enum context_type type;
     int argc;
@@ -211,8 +226,7 @@ typedef struct rb_context_struct {
     rb_execution_context_t saved_ec;
     rb_jmpbuf_t jmpbuf;
     rb_ensure_entry_t *ensure_array;
-    /* Pointer to MJIT info about the continuation.  */
-    struct mjit_cont *mjit_cont;
+    struct rb_jit_cont *jit_cont; // Continuation contexts for JITs
 } rb_context_t;
 
 
@@ -258,7 +272,7 @@ struct rb_fiber_struct {
 
 static struct fiber_pool shared_fiber_pool = {NULL, NULL, 0, 0, 0, 0};
 
-static ID fiber_initialize_keywords[2] = {0};
+static ID fiber_initialize_keywords[3] = {0};
 
 /*
  * FreeBSD require a first (i.e. addr) argument of mmap(2) is not NULL
@@ -274,7 +288,6 @@ static ID fiber_initialize_keywords[2] = {0};
 #define ERRNOMSG strerror(errno)
 
 // Locates the stack vacancy details for the given stack.
-// Requires that fiber_pool_vacancy fits within one page.
 inline static struct fiber_pool_vacancy *
 fiber_pool_vacancy_pointer(void * base, size_t size)
 {
@@ -285,6 +298,24 @@ fiber_pool_vacancy_pointer(void * base, size_t size)
     );
 }
 
+#if defined(COROUTINE_SANITIZE_ADDRESS)
+// Compute the base pointer for a vacant stack, for the area which can be poisoned.
+inline static void *
+fiber_pool_stack_poison_base(struct fiber_pool_stack * stack)
+{
+    STACK_GROW_DIR_DETECTION;
+
+    return (char*)stack->base + STACK_DIR_UPPER(RB_PAGE_SIZE, 0);
+}
+
+// Compute the size of the vacant stack, for the area that can be poisoned.
+inline static size_t
+fiber_pool_stack_poison_size(struct fiber_pool_stack * stack)
+{
+    return stack->size - RB_PAGE_SIZE;
+}
+#endif
+
 // Reset the current stack pointer and available size of the given stack.
 inline static void
 fiber_pool_stack_reset(struct fiber_pool_stack * stack)
@@ -634,6 +665,10 @@ fiber_pool_stack_acquire(struct fiber_pool * fiber_pool)
     VM_ASSERT(vacancy);
     VM_ASSERT(vacancy->stack.base);
 
+#if defined(COROUTINE_SANITIZE_ADDRESS)
+    __asan_unpoison_memory_region(fiber_pool_stack_poison_base(&vacancy->stack), fiber_pool_stack_poison_size(&vacancy->stack));
+#endif
+
     // Take the top item from the free list:
     fiber_pool->used += 1;
 
@@ -659,26 +694,45 @@ fiber_pool_stack_free(struct fiber_pool_stack * stack)
 
     if (DEBUG) fprintf(stderr, "fiber_pool_stack_free: %p+%"PRIuSIZE" [base=%p, size=%"PRIuSIZE"]\n", base, size, stack->base, stack->size);
 
-#if VM_CHECK_MODE > 0 && defined(MADV_DONTNEED)
+    // The pages being used by the stack can be returned back to the system.
+    // That doesn't change the page mapping, but it does allow the system to
+    // reclaim the physical memory.
+    // Since we no longer care about the data itself, we don't need to page
+    // out to disk, since that is costly. Not all systems support that, so
+    // we try our best to select the most efficient implementation.
+    // In addition, it's actually slightly desirable to not do anything here,
+    // but that results in higher memory usage.
+
+#ifdef __wasi__
+    // WebAssembly doesn't support madvise, so we just don't do anything.
+#elif VM_CHECK_MODE > 0 && defined(MADV_DONTNEED)
     // This immediately discards the pages and the memory is reset to zero.
     madvise(base, size, MADV_DONTNEED);
-#elif defined(POSIX_MADV_DONTNEED)
-    posix_madvise(base, size, POSIX_MADV_DONTNEED);
 #elif defined(MADV_FREE_REUSABLE)
+    // Darwin / macOS / iOS.
     // Acknowledge the kernel down to the task info api we make this
     // page reusable for future use.
     // As for MADV_FREE_REUSE below we ensure in the rare occasions the task was not
     // completed at the time of the call to re-iterate.
     while (madvise(base, size, MADV_FREE_REUSABLE) == -1 && errno == EAGAIN);
 #elif defined(MADV_FREE)
+    // Recent Linux.
     madvise(base, size, MADV_FREE);
 #elif defined(MADV_DONTNEED)
+    // Old Linux.
     madvise(base, size, MADV_DONTNEED);
+#elif defined(POSIX_MADV_DONTNEED)
+    // Solaris?
+    posix_madvise(base, size, POSIX_MADV_DONTNEED);
 #elif defined(_WIN32)
     VirtualAlloc(base, size, MEM_RESET, PAGE_READWRITE);
     // Not available in all versions of Windows.
     //DiscardVirtualMemory(base, size);
 #endif
+
+#if defined(COROUTINE_SANITIZE_ADDRESS)
+    __asan_poison_memory_region(fiber_pool_stack_poison_base(stack), fiber_pool_stack_poison_size(stack));
+#endif
 }
 
 // Release and return a stack to the vacancy list.
@@ -698,7 +752,7 @@ fiber_pool_stack_release(struct fiber_pool_stack * stack)
     fiber_pool_vacancy_reset(vacancy);
 
     // Push the vacancy into the vancancies list:
-    pool->vacancies = fiber_pool_vacancy_push(vacancy, stack->pool->vacancies);
+    pool->vacancies = fiber_pool_vacancy_push(vacancy, pool->vacancies);
     pool->used -= 1;
 
 #ifdef FIBER_POOL_ALLOCATION_FREE
@@ -714,7 +768,8 @@ fiber_pool_stack_release(struct fiber_pool_stack * stack)
         fiber_pool_stack_free(&vacancy->stack);
     }
 #else
-    // This is entirely optional, but clears the dirty flag from the stack memory, so it won't get swapped to disk when there is memory pressure:
+    // This is entirely optional, but clears the dirty flag from the stack
+    // memory, so it won't get swapped to disk when there is memory pressure:
     if (stack->pool->free_stacks) {
         fiber_pool_stack_free(&vacancy->stack);
     }
@@ -751,6 +806,20 @@ static COROUTINE
 fiber_entry(struct coroutine_context * from, struct coroutine_context * to)
 {
     rb_fiber_t *fiber = to->argument;
+
+#if defined(COROUTINE_SANITIZE_ADDRESS)
+    // Address sanitizer will copy the previous stack base and stack size into
+    // the "from" fiber. `coroutine_initialize_main` doesn't generally know the
+    // stack bounds (base + size). Therefore, the main fiber `stack_base` and
+    // `stack_size` will be NULL/0. It's specifically important in that case to
+    // get the (base+size) of the previous fiber and save it, so that later when
+    // we return to the main coroutine, we don't supply (NULL, 0) to
+    // __sanitizer_start_switch_fiber which royally messes up the internal state
+    // of ASAN and causes (sometimes) the following message:
+    // "WARNING: ASan is ignoring requested __asan_handle_no_return"
+    __sanitizer_finish_switch_fiber(to->fake_stack, (const void**)&from->stack_base, &from->stack_size);
+#endif
+
     rb_thread_t *thread = fiber->cont.saved_ec.thread_ptr;
 
 #ifdef COROUTINE_PTHREAD_CONTEXT
@@ -791,7 +860,8 @@ fiber_initialize_coroutine(rb_fiber_t *fiber, size_t * vm_stack_size)
     return vm_stack;
 }
 
-// Release the stack from the fiber, it's execution context, and return it to the fiber pool.
+// Release the stack from the fiber, it's execution context, and return it to
+// the fiber pool.
 static void
 fiber_stack_release(rb_fiber_t * fiber)
 {
@@ -958,6 +1028,8 @@ fiber_is_root_p(const rb_fiber_t *fiber)
 }
 #endif
 
+static void jit_cont_free(struct rb_jit_cont *cont);
+
 static void
 cont_free(void *ptr)
 {
@@ -978,9 +1050,9 @@ cont_free(void *ptr)
 
     RUBY_FREE_UNLESS_NULL(cont->saved_vm_stack.ptr);
 
-    if (mjit_enabled) {
-        VM_ASSERT(cont->mjit_cont != NULL);
-        mjit_cont_free(cont->mjit_cont);
+    if (jit_cont_enabled) {
+        VM_ASSERT(cont->jit_cont != NULL);
+        jit_cont_free(cont->jit_cont);
     }
     /* free rb_cont_t or rb_fiber_t */
     ruby_xfree(ptr);
@@ -1085,7 +1157,9 @@ fiber_memsize(const void *ptr)
      */
     if (saved_ec->local_storage && fiber != th->root_fiber) {
         size += rb_id_table_memsize(saved_ec->local_storage);
+        size += rb_obj_memsize_of(saved_ec->storage);
     }
+
     size += cont_memsize(&fiber->cont);
     return size;
 }
@@ -1120,6 +1194,7 @@ cont_save_machine_stack(rb_thread_t *th, rb_context_t *cont)
     }
 
     FLUSH_REGISTER_WINDOWS;
+    asan_unpoison_memory_region(cont->machine.stack_src, size, false);
     MEMCPY(cont->machine.stack, cont->machine.stack_src, VALUE, size);
 }
 
@@ -1144,13 +1219,110 @@ cont_save_thread(rb_context_t *cont, rb_thread_t *th)
     sec->machine.stack_end = NULL;
 }
 
+static rb_nativethread_lock_t jit_cont_lock;
+
+// Register a new continuation with execution context `ec`. Return JIT info about
+// the continuation.
+static struct rb_jit_cont *
+jit_cont_new(rb_execution_context_t *ec)
+{
+    struct rb_jit_cont *cont;
+
+    // We need to use calloc instead of something like ZALLOC to avoid triggering GC here.
+    // When this function is called from rb_thread_alloc through rb_threadptr_root_fiber_setup,
+    // the thread is still being prepared and marking it causes SEGV.
+    cont = calloc(1, sizeof(struct rb_jit_cont));
+    if (cont == NULL)
+        rb_memerror();
+    cont->ec = ec;
+
+    rb_native_mutex_lock(&jit_cont_lock);
+    if (first_jit_cont == NULL) {
+        cont->next = cont->prev = NULL;
+    }
+    else {
+        cont->prev = NULL;
+        cont->next = first_jit_cont;
+        first_jit_cont->prev = cont;
+    }
+    first_jit_cont = cont;
+    rb_native_mutex_unlock(&jit_cont_lock);
+
+    return cont;
+}
+
+// Unregister continuation `cont`.
 static void
-cont_init_mjit_cont(rb_context_t *cont)
+jit_cont_free(struct rb_jit_cont *cont)
 {
-    VM_ASSERT(cont->mjit_cont == NULL);
-    if (mjit_enabled) {
-        cont->mjit_cont = mjit_cont_new(&(cont->saved_ec));
+    if (!cont) return;
+
+    rb_native_mutex_lock(&jit_cont_lock);
+    if (cont == first_jit_cont) {
+        first_jit_cont = cont->next;
+        if (first_jit_cont != NULL)
+            first_jit_cont->prev = NULL;
     }
+    else {
+        cont->prev->next = cont->next;
+        if (cont->next != NULL)
+            cont->next->prev = cont->prev;
+    }
+    rb_native_mutex_unlock(&jit_cont_lock);
+
+    free(cont);
+}
+
+// Call a given callback against all on-stack ISEQs.
+void
+rb_jit_cont_each_iseq(rb_iseq_callback callback, void *data)
+{
+    struct rb_jit_cont *cont;
+    for (cont = first_jit_cont; cont != NULL; cont = cont->next) {
+        if (cont->ec->vm_stack == NULL)
+            continue;
+
+        const rb_control_frame_t *cfp;
+        for (cfp = RUBY_VM_END_CONTROL_FRAME(cont->ec) - 1; ; cfp = RUBY_VM_NEXT_CONTROL_FRAME(cfp)) {
+            const rb_iseq_t *iseq;
+            if (cfp->pc && (iseq = cfp->iseq) != NULL && imemo_type((VALUE)iseq) == imemo_iseq) {
+                callback(iseq, data);
+            }
+
+            if (cfp == cont->ec->cfp)
+                break; // reached the most recent cfp
+        }
+    }
+}
+
+// Finish working with jit_cont.
+void
+rb_jit_cont_finish(void)
+{
+    if (!jit_cont_enabled)
+        return;
+
+    struct rb_jit_cont *cont, *next;
+    for (cont = first_jit_cont; cont != NULL; cont = next) {
+        next = cont->next;
+        free(cont); // Don't use xfree because it's allocated by calloc.
+    }
+    rb_native_mutex_destroy(&jit_cont_lock);
+}
+
+static void
+cont_init_jit_cont(rb_context_t *cont)
+{
+    VM_ASSERT(cont->jit_cont == NULL);
+    if (jit_cont_enabled) {
+        cont->jit_cont = jit_cont_new(&(cont->saved_ec));
+    }
+}
+
+struct rb_execution_context_struct *
+rb_fiberptr_get_ec(struct rb_fiber_struct *fiber)
+{
+    return &fiber->cont.saved_ec;
 }
 
 static void
@@ -1162,7 +1334,7 @@ cont_init(rb_context_t *cont, rb_thread_t *th)
     cont->saved_ec.local_storage = NULL;
     cont->saved_ec.local_storage_recursive_hash = Qnil;
     cont->saved_ec.local_storage_recursive_hash_for_trace = Qnil;
-    cont_init_mjit_cont(cont);
+    cont_init_jit_cont(cont);
 }
 
 static rb_context_t *
@@ -1191,11 +1363,15 @@ rb_fiberptr_blocking(struct rb_fiber_struct *fiber)
     return fiber->blocking;
 }
 
-// This is used for root_fiber because other fibers call cont_init_mjit_cont through cont_new.
+// Start working with jit_cont.
 void
-rb_fiber_init_mjit_cont(struct rb_fiber_struct *fiber)
+rb_jit_cont_init(void)
 {
-    cont_init_mjit_cont(&fiber->cont);
+    if (!jit_cont_enabled)
+        return;
+
+    rb_native_mutex_initialize(&jit_cont_lock);
+    cont_init_jit_cont(&GET_EC()->fiber_ptr->cont);
 }
 
 #if 0
@@ -1225,10 +1401,7 @@ show_vm_pcs(const rb_control_frame_t *cfp,
     }
 }
 #endif
-COMPILER_WARNING_PUSH
-#ifdef __clang__
-COMPILER_WARNING_IGNORED(-Wduplicate-decl-specifier)
-#endif
+
 static VALUE
 cont_capture(volatile int *volatile stat)
 {
@@ -1272,7 +1445,7 @@ cont_capture(volatile int *volatile stat)
         entry = cont->ensure_array = ALLOC_N(rb_ensure_entry_t,size+1);
         for (p=th->ec->ensure_list; p; p=p->next) {
             if (!p->entry.marker)
-                p->entry.marker = rb_ary_tmp_new(0); /* dummy object */
+                p->entry.marker = rb_ary_hidden_new(0); /* dummy object */
             *entry++ = p->entry;
         }
         entry->marker = 0;
@@ -1293,7 +1466,6 @@ cont_capture(volatile int *volatile stat)
         return contval;
     }
 }
-COMPILER_WARNING_POP
 
 static inline void
 cont_restore_thread(rb_context_t *cont)
@@ -1379,9 +1551,17 @@ fiber_setcontext(rb_fiber_t *new_fiber, rb_fiber_t *old_fiber)
 
     // if (DEBUG) fprintf(stderr, "fiber_setcontext: %p[%p] -> %p[%p]\n", (void*)old_fiber, old_fiber->stack.base, (void*)new_fiber, new_fiber->stack.base);
 
+#if defined(COROUTINE_SANITIZE_ADDRESS)
+    __sanitizer_start_switch_fiber(FIBER_TERMINATED_P(old_fiber) ? NULL : &old_fiber->context.fake_stack, new_fiber->context.stack_base, new_fiber->context.stack_size);
+#endif
+
     /* swap machine context */
     struct coroutine_context * from = coroutine_transfer(&old_fiber->context, &new_fiber->context);
 
+#if defined(COROUTINE_SANITIZE_ADDRESS)
+    __sanitizer_finish_switch_fiber(old_fiber->context.fake_stack, NULL, NULL);
+#endif
+
     if (from == NULL) {
         rb_syserr_fail(errno, "coroutine_transfer");
     }
@@ -1401,7 +1581,7 @@ cont_restore_1(rb_context_t *cont)
     cont_restore_thread(cont);
 
     /* restore machine stack */
-#ifdef _M_AMD64
+#if defined(_M_AMD64) && !defined(__MINGW64__)
     {
         /* workaround for x64 SEH */
         jmp_buf buf;
@@ -1441,6 +1621,10 @@ cont_restore_0(rb_context_t *cont, VALUE *addr_in_prev_frame)
             if (&space[0] > end) {
 # ifdef HAVE_ALLOCA
                 volatile VALUE *sp = ALLOCA_N(VALUE, &space[0] - end);
+                // We need to make sure that the stack pointer is moved,
+                // but some compilers may remove the allocation by optimization.
+                // We hope that the following read/write will prevent such an optimization.
+                *sp = Qfalse;
                 space[0] = *sp;
 # else
                 cont_restore_0(cont, &space[0]);
@@ -1652,7 +1836,7 @@ rollback_ensure_stack(VALUE self,rb_ensure_list_t *current,rb_ensure_entry_t *ta
     /* push ensure stack */
     for (j = 0; j < i; j++) {
         func = lookup_rollback_func(target[i - j - 1].e_proc);
-        if ((VALUE)func != Qundef) {
+        if (!UNDEF_P((VALUE)func)) {
             (*func)(target[i - j - 1].data2);
         }
     }
@@ -1777,7 +1961,7 @@ rb_cont_call(int argc, VALUE *argv, VALUE contval)
  *  the current thread, blocking and non-blocking fibers' behavior is identical.
  *
  *  Ruby doesn't provide a scheduler class: it is expected to be implemented by
- *  the user and correspond to Fiber::SchedulerInterface.
+ *  the user and correspond to Fiber::Scheduler.
  *
  *  There is also Fiber.schedule method, which is expected to immediately perform
  *  the given block in a non-blocking manner. Its actual implementation is up to
@@ -1828,11 +2012,207 @@ fiber_t_alloc(VALUE fiber_value, unsigned int blocking)
     return fiber;
 }
 
+static rb_fiber_t *
+root_fiber_alloc(rb_thread_t *th)
+{
+    VALUE fiber_value = fiber_alloc(rb_cFiber);
+    rb_fiber_t *fiber = th->ec->fiber_ptr;
+
+    VM_ASSERT(DATA_PTR(fiber_value) == NULL);
+    VM_ASSERT(fiber->cont.type == FIBER_CONTEXT);
+    VM_ASSERT(FIBER_RESUMED_P(fiber));
+
+    th->root_fiber = fiber;
+    DATA_PTR(fiber_value) = fiber;
+    fiber->cont.self = fiber_value;
+
+    coroutine_initialize_main(&fiber->context);
+
+    return fiber;
+}
+
+static inline rb_fiber_t*
+fiber_current(void)
+{
+    rb_execution_context_t *ec = GET_EC();
+    if (ec->fiber_ptr->cont.self == 0) {
+        root_fiber_alloc(rb_ec_thread_ptr(ec));
+    }
+    return ec->fiber_ptr;
+}
+
+static inline VALUE
+current_fiber_storage(void)
+{
+    rb_execution_context_t *ec = GET_EC();
+    return ec->storage;
+}
+
+static inline VALUE
+inherit_fiber_storage(void)
+{
+    return rb_obj_dup(current_fiber_storage());
+}
+
+static inline void
+fiber_storage_set(struct rb_fiber_struct *fiber, VALUE storage)
+{
+    fiber->cont.saved_ec.storage = storage;
+}
+
+static inline VALUE
+fiber_storage_get(rb_fiber_t *fiber)
+{
+    VALUE storage = fiber->cont.saved_ec.storage;
+    if (storage == Qnil) {
+        storage = rb_hash_new();
+        fiber_storage_set(fiber, storage);
+    }
+    return storage;
+}
+
+static void
+storage_access_must_be_from_same_fiber(VALUE self)
+{
+    rb_fiber_t *fiber = fiber_ptr(self);
+    rb_fiber_t *current = fiber_current();
+    if (fiber != current) {
+        rb_raise(rb_eArgError, "Fiber storage can only be accessed from the Fiber it belongs to");
+    }
+}
+
+/**
+ *  call-seq: fiber.storage -> hash (dup)
+ *
+ *  Returns a copy of the storage hash for the fiber. The method can only be called on the
+ *  Fiber.current.
+ */
+static VALUE
+rb_fiber_storage_get(VALUE self)
+{
+    storage_access_must_be_from_same_fiber(self);
+    return rb_obj_dup(fiber_storage_get(fiber_ptr(self)));
+}
+
+static int
+fiber_storage_validate_each(VALUE key, VALUE value, VALUE _argument)
+{
+    Check_Type(key, T_SYMBOL);
+
+    return ST_CONTINUE;
+}
+
+static void
+fiber_storage_validate(VALUE value)
+{
+    // nil is an allowed value and will be lazily initialized.
+    if (value == Qnil) return;
+
+    if (!RB_TYPE_P(value, T_HASH)) {
+        rb_raise(rb_eTypeError, "storage must be a hash");
+    }
+
+    if (RB_OBJ_FROZEN(value)) {
+        rb_raise(rb_eFrozenError, "storage must not be frozen");
+    }
+
+    rb_hash_foreach(value, fiber_storage_validate_each, Qundef);
+}
+
+/**
+ *  call-seq: fiber.storage = hash
+ *
+ *  Sets the storage hash for the fiber. This feature is experimental
+ *  and may change in the future. The method can only be called on the
+ *  Fiber.current.
+ *
+ *  You should be careful about using this method as you may inadvertently clear
+ *  important fiber-storage state. You should mostly prefer to assign specific
+ *  keys in the storage using Fiber::[]=.
+ *
+ *  You can also use <tt>Fiber.new(storage: nil)</tt> to create a fiber with an empty
+ *  storage.
+ *
+ *  Example:
+ *
+ *    while request = request_queue.pop
+ *      # Reset the per-request state:
+ *      Fiber.current.storage = nil
+ *      handle_request(request)
+ *    end
+ */
+static VALUE
+rb_fiber_storage_set(VALUE self, VALUE value)
+{
+    if (rb_warning_category_enabled_p(RB_WARN_CATEGORY_EXPERIMENTAL)) {
+        rb_category_warn(RB_WARN_CATEGORY_EXPERIMENTAL,
+          "Fiber#storage= is experimental and may be removed in the future!");
+    }
+
+    storage_access_must_be_from_same_fiber(self);
+    fiber_storage_validate(value);
+
+    fiber_ptr(self)->cont.saved_ec.storage = rb_obj_dup(value);
+    return value;
+}
+
+/**
+ *  call-seq: Fiber[key] -> value
+ *
+ *  Returns the value of the fiber storage variable identified by +key+.
+ *
+ *  The +key+ must be a symbol, and the value is set by Fiber#[]= or
+ *  Fiber#store.
+ *
+ *  See also Fiber::[]=.
+ */
 static VALUE
-fiber_initialize(VALUE self, VALUE proc, struct fiber_pool * fiber_pool, unsigned int blocking)
+rb_fiber_storage_aref(VALUE class, VALUE key)
 {
+    Check_Type(key, T_SYMBOL);
+
+    VALUE storage = fiber_storage_get(fiber_current());
+
+    if (storage == Qnil) return Qnil;
+
+    return rb_hash_aref(storage, key);
+}
+
+/**
+ *  call-seq: Fiber[key] = value
+ *
+ *  Assign +value+ to the fiber storage variable identified by +key+.
+ *  The variable is created if it doesn't exist.
+ *
+ *  +key+ must be a Symbol, otherwise a TypeError is raised.
+ *
+ *  See also Fiber::[].
+ */
+static VALUE
+rb_fiber_storage_aset(VALUE class, VALUE key, VALUE value)
+{
+    Check_Type(key, T_SYMBOL);
+
+    VALUE storage = fiber_storage_get(fiber_current());
+
+    return rb_hash_aset(storage, key, value);
+}
+
+static VALUE
+fiber_initialize(VALUE self, VALUE proc, struct fiber_pool * fiber_pool, unsigned int blocking, VALUE storage)
+{
+    if (storage == Qundef || storage == Qtrue) {
+        // The default, inherit storage (dup) from the current fiber:
+        storage = inherit_fiber_storage();
+    }
+    else /* nil, hash, etc. */ {
+        fiber_storage_validate(storage);
+        storage = rb_obj_dup(storage);
+    }
+
     rb_fiber_t *fiber = fiber_t_alloc(self, blocking);
 
+    fiber->cont.saved_ec.storage = storage;
     fiber->first_proc = proc;
     fiber->stack.base = NULL;
     fiber->stack.pool = fiber_pool;
@@ -1865,54 +2245,90 @@ rb_fiber_pool_default(VALUE pool)
     return &shared_fiber_pool;
 }
 
+VALUE rb_fiber_inherit_storage(struct rb_execution_context_struct *ec, struct rb_fiber_struct *fiber)
+{
+    VALUE storage = rb_obj_dup(ec->storage);
+    fiber->cont.saved_ec.storage = storage;
+    return storage;
+}
+
 /* :nodoc: */
 static VALUE
 rb_fiber_initialize_kw(int argc, VALUE* argv, VALUE self, int kw_splat)
 {
     VALUE pool = Qnil;
     VALUE blocking = Qfalse;
+    VALUE storage = Qundef;
 
     if (kw_splat != RB_NO_KEYWORDS) {
         VALUE options = Qnil;
-        VALUE arguments[2] = {Qundef};
+        VALUE arguments[3] = {Qundef};
 
         argc = rb_scan_args_kw(kw_splat, argc, argv, ":", &options);
-        rb_get_kwargs(options, fiber_initialize_keywords, 0, 2, arguments);
+        rb_get_kwargs(options, fiber_initialize_keywords, 0, 3, arguments);
 
-        if (arguments[0] != Qundef) {
+        if (!UNDEF_P(arguments[0])) {
             blocking = arguments[0];
         }
 
-        if (arguments[1] != Qundef) {
+        if (!UNDEF_P(arguments[1])) {
             pool = arguments[1];
         }
+
+        storage = arguments[2];
     }
 
-    return fiber_initialize(self, rb_block_proc(), rb_fiber_pool_default(pool), RTEST(blocking));
+    return fiber_initialize(self, rb_block_proc(), rb_fiber_pool_default(pool), RTEST(blocking), storage);
 }
 
 /*
  *  call-seq:
- *     Fiber.new(blocking: false) { |*args| ... } -> fiber
+ *     Fiber.new(blocking: false, storage: true) { |*args| ... } -> fiber
  *
- *  Creates new Fiber. Initially, the fiber is not running and can be resumed with
- *  #resume. Arguments to the first #resume call will be passed to the block:
+ *  Creates new Fiber. Initially, the fiber is not running and can be resumed
+ *  with #resume. Arguments to the first #resume call will be passed to the
+ *  block:
  *
- *      f = Fiber.new do |initial|
- *         current = initial
- *         loop do
- *           puts "current: #{current.inspect}"
- *           current = Fiber.yield
- *         end
- *      end
- *      f.resume(100)     # prints: current: 100
- *      f.resume(1, 2, 3) # prints: current: [1, 2, 3]
- *      f.resume          # prints: current: nil
- *      # ... and so on ...
- *
- *  If <tt>blocking: false</tt> is passed to <tt>Fiber.new</tt>, _and_ current thread
- *  has a Fiber.scheduler defined, the Fiber becomes non-blocking (see "Non-blocking
- *  Fibers" section in class docs).
+ *    f = Fiber.new do |initial|
+ *       current = initial
+ *       loop do
+ *         puts "current: #{current.inspect}"
+ *         current = Fiber.yield
+ *       end
+ *    end
+ *    f.resume(100)     # prints: current: 100
+ *    f.resume(1, 2, 3) # prints: current: [1, 2, 3]
+ *    f.resume          # prints: current: nil
+ *    # ... and so on ...
+ *
+ *  If <tt>blocking: false</tt> is passed to <tt>Fiber.new</tt>, _and_ current
+ *  thread has a Fiber.scheduler defined, the Fiber becomes non-blocking (see
+ *  "Non-blocking Fibers" section in class docs).
+ *
+ *  If the <tt>storage</tt> is unspecified, the default is to inherit a copy of
+ *  the storage from the current fiber. This is the same as specifying
+ *  <tt>storage: true</tt>.
+ *
+ *    Fiber[:x] = 1
+ *    Fiber.new do
+ *      Fiber[:x] # => 1
+ *      Fiber[:x] = 2
+ *    end.resume
+ *    Fiber[:x] # => 1
+ *
+ *  If the given <tt>storage</tt> is <tt>nil</tt>, this function will lazy
+ *  initialize the internal storage, which starts as an empty hash.
+ *
+ *    Fiber[:x] = "Hello World"
+ *    Fiber.new(storage: nil) do
+ *      Fiber[:x] # nil
+ *    end
+ *
+ *  Otherwise, the given <tt>storage</tt> is used as the new fiber's storage,
+ *  and it must be an instance of Hash.
+ *
+ *  Explicitly using <tt>storage: true</tt> is currently experimental and may
+ *  change in the future.
  */
 static VALUE
 rb_fiber_initialize(int argc, VALUE* argv, VALUE self)
@@ -1921,9 +2337,15 @@ rb_fiber_initialize(int argc, VALUE* argv, VALUE self)
 }
 
 VALUE
+rb_fiber_new_storage(rb_block_call_func_t func, VALUE obj, VALUE storage)
+{
+    return fiber_initialize(fiber_alloc(rb_cFiber), rb_proc_new(func, obj), rb_fiber_pool_default(Qnil), 0, storage);
+}
+
+VALUE
 rb_fiber_new(rb_block_call_func_t func, VALUE obj)
 {
-    return fiber_initialize(fiber_alloc(rb_cFiber), rb_proc_new(func, obj), rb_fiber_pool_default(Qnil), 1);
+    return rb_fiber_new_storage(func, obj, Qtrue);
 }
 
 static VALUE
@@ -1934,7 +2356,7 @@ rb_fiber_s_schedule_kw(int argc, VALUE* argv, int kw_splat)
     VALUE fiber = Qnil;
 
     if (scheduler != Qnil) {
-        fiber = rb_funcall_passing_block_kw(scheduler, rb_intern("fiber"), argc, argv, kw_splat);
+        fiber = rb_fiber_scheduler_fiber(scheduler, argc, argv, kw_splat);
     }
     else {
         rb_raise(rb_eRuntimeError, "No scheduler is available!");
@@ -1977,7 +2399,7 @@ rb_fiber_s_schedule_kw(int argc, VALUE* argv, int kw_splat)
  *
  *  Note that the behavior described above is how the method is <em>expected</em>
  *  to behave, actual behavior is up to the current scheduler's implementation of
- *  Fiber::SchedulerInterface#fiber method. Ruby doesn't enforce this method to
+ *  Fiber::Scheduler#fiber method. Ruby doesn't enforce this method to
  *  behave in any particular way.
  *
  *  If the scheduler is not set, the method raises
@@ -1996,7 +2418,7 @@ rb_fiber_s_schedule(int argc, VALUE *argv, VALUE obj)
  *
  *  Returns the Fiber scheduler, that was last set for the current thread with Fiber.set_scheduler.
  *  Returns +nil+ if no scheduler is set (which is the default), and non-blocking fibers'
- #  behavior is the same as blocking.
+ *  behavior is the same as blocking.
  *  (see "Non-blocking fibers" section in class docs for details about the scheduler concept).
  *
  */
@@ -2030,7 +2452,7 @@ rb_fiber_current_scheduler(VALUE klass)
  *  thread will call scheduler's +close+ method on finalization (allowing the scheduler to
  *  properly manage all non-finished fibers).
  *
- *  +scheduler+ can be an object of any class corresponding to Fiber::SchedulerInterface. Its
+ *  +scheduler+ can be an object of any class corresponding to Fiber::Scheduler. Its
  *  implementation is up to the user.
  *
  *  See also the "Non-blocking fibers" section in class docs.
@@ -2097,25 +2519,7 @@ rb_fiber_start(rb_fiber_t *fiber)
     rb_fiber_terminate(fiber, need_interrupt, err);
 }
 
-static rb_fiber_t *
-root_fiber_alloc(rb_thread_t *th)
-{
-    VALUE fiber_value = fiber_alloc(rb_cFiber);
-    rb_fiber_t *fiber = th->ec->fiber_ptr;
-
-    VM_ASSERT(DATA_PTR(fiber_value) == NULL);
-    VM_ASSERT(fiber->cont.type == FIBER_CONTEXT);
-    VM_ASSERT(fiber->status == FIBER_RESUMED);
-
-    th->root_fiber = fiber;
-    DATA_PTR(fiber_value) = fiber;
-    fiber->cont.self = fiber_value;
-
-    coroutine_initialize_main(&fiber->context);
-
-    return fiber;
-}
-
+// Set up a "root fiber", which is the fiber that every Ractor has.
 void
 rb_threadptr_root_fiber_setup(rb_thread_t *th)
 {
@@ -2130,9 +2534,11 @@ rb_threadptr_root_fiber_setup(rb_thread_t *th)
     fiber->blocking = 1;
     fiber_status_set(fiber, FIBER_RESUMED); /* skip CREATED */
     th->ec = &fiber->cont.saved_ec;
-    // This skips mjit_cont_new for the initial thread because mjit_enabled is always false
-    // at this point. mjit_init calls rb_fiber_init_mjit_cont again for this root_fiber.
-    rb_fiber_init_mjit_cont(fiber);
+    // When rb_threadptr_root_fiber_setup is called for the first time, mjit_enabled and
+    // rb_yjit_enabled_p() are still false. So this does nothing and rb_jit_cont_init() that is
+    // called later will take care of it. However, you still have to call cont_init_jit_cont()
+    // here for other Ractors, which are not initialized by rb_jit_cont_init().
+    cont_init_jit_cont(&fiber->cont);
 }
 
 void
@@ -2167,16 +2573,6 @@ rb_threadptr_root_fiber_terminate(rb_thread_t *th)
 }
 
 static inline rb_fiber_t*
-fiber_current(void)
-{
-    rb_execution_context_t *ec = GET_EC();
-    if (ec->fiber_ptr->cont.self == 0) {
-        root_fiber_alloc(rb_ec_thread_ptr(ec));
-    }
-    return ec->fiber_ptr;
-}
-
-static inline rb_fiber_t*
 return_fiber(bool terminate)
 {
     rb_fiber_t *fiber = fiber_current();
@@ -2353,7 +2749,60 @@ rb_fiber_transfer(VALUE fiber_value, int argc, const VALUE *argv)
 VALUE
 rb_fiber_blocking_p(VALUE fiber)
 {
-    return RBOOL(fiber_ptr(fiber)->blocking != 0);
+    return RBOOL(fiber_ptr(fiber)->blocking);
+}
+
+static VALUE
+fiber_blocking_yield(VALUE fiber_value)
+{
+    rb_fiber_t *fiber = fiber_ptr(fiber_value);
+    rb_thread_t * volatile th = fiber->cont.saved_ec.thread_ptr;
+
+    // fiber->blocking is `unsigned int : 1`, so we use it as a boolean:
+    fiber->blocking = 1;
+
+    // Once the fiber is blocking, and current, we increment the thread blocking state:
+    th->blocking += 1;
+
+    return rb_yield(fiber_value);
+}
+
+static VALUE
+fiber_blocking_ensure(VALUE fiber_value)
+{
+    rb_fiber_t *fiber = fiber_ptr(fiber_value);
+    rb_thread_t * volatile th = fiber->cont.saved_ec.thread_ptr;
+
+    // We are no longer blocking:
+    fiber->blocking = 0;
+    th->blocking -= 1;
+
+    return Qnil;
+}
+
+/*
+ *  call-seq:
+ *     Fiber.blocking{|fiber| ...} -> result
+ *
+ *  Forces the fiber to be blocking for the duration of the block. Returns the
+ *  result of the block.
+ *
+ *  See the "Non-blocking fibers" section in class docs for details.
+ *
+ */
+VALUE
+rb_fiber_blocking(VALUE class)
+{
+    VALUE fiber_value = rb_fiber_current();
+    rb_fiber_t *fiber = fiber_ptr(fiber_value);
+
+    // If we are already blocking, this is essentially a no-op:
+    if (fiber->blocking) {
+        return rb_yield(fiber_value);
+    }
+    else {
+        return rb_ensure(fiber_blocking_yield, fiber_value, fiber_blocking_ensure, fiber_value);
+    }
 }
 
 /*
@@ -2439,9 +2888,7 @@ fiber_resume_kw(rb_fiber_t *fiber, int argc, const VALUE *argv, int kw_splat)
         rb_raise(rb_eFiberError, "attempt to resume a transferring fiber");
     }
 
-    VALUE result = fiber_switch(fiber, argc, argv, kw_splat, fiber, false);
-
-    return result;
+    return fiber_switch(fiber, argc, argv, kw_splat, fiber, false);
 }
 
 VALUE
@@ -2893,329 +3340,6 @@ rb_fiber_pool_initialize(int argc, VALUE* argv, VALUE self)
  *     fiber.resume #=> FiberError: dead fiber called
  */
 
-/*
- *  Document-class: Fiber::SchedulerInterface
- *
- *  This is not an existing class, but documentation of the interface that Scheduler
- *  object should comply to in order to be used as argument to Fiber.scheduler and handle non-blocking
- *  fibers. See also the "Non-blocking fibers" section in Fiber class docs for explanations
- *  of some concepts.
- *
- *  Scheduler's behavior and usage are expected to be as follows:
- *
- *  * When the execution in the non-blocking Fiber reaches some blocking operation (like
- *    sleep, wait for a process, or a non-ready I/O), it calls some of the scheduler's
- *    hook methods, listed below.
- *  * Scheduler somehow registers what the current fiber is waiting on, and yields control
- *    to other fibers with Fiber.yield (so the fiber would be suspended while expecting its
- *    wait to end, and other fibers in the same thread can perform)
- *  * At the end of the current thread execution, the scheduler's method #close is called
- *  * The scheduler runs into a wait loop, checking all the blocked fibers (which it has
- *    registered on hook calls) and resuming them when the awaited resource is ready
- *    (e.g. I/O ready or sleep time elapsed).
- *
- *  A typical implementation would probably rely for this closing loop on a gem like
- *  EventMachine[https://github.com/eventmachine/eventmachine] or
- *  Async[https://github.com/socketry/async].
- *
- *  This way concurrent execution will be achieved transparently for every
- *  individual Fiber's code.
- *
- *  Hook methods are:
- *
- *  * #io_wait, #io_read, and #io_write
- *  * #process_wait
- *  * #kernel_sleep
- *  * #timeout_after
- *  * #address_resolve
- *  * #block and #unblock
- *  * (the list is expanded as Ruby developers make more methods having non-blocking calls)
- *
- *  When not specified otherwise, the hook implementations are mandatory: if they are not
- *  implemented, the methods trying to call hook will fail. To provide backward compatibility,
- *  in the future hooks will be optional (if they are not implemented, due to the scheduler
- *  being created for the older Ruby version, the code which needs this hook will not fail,
- *  and will just behave in a blocking fashion).
- *
- *  It is also strongly recommended that the scheduler implements the #fiber method, which is
- *  delegated to by Fiber.schedule.
- *
- *  Sample _toy_ implementation of the scheduler can be found in Ruby's code, in
- *  <tt>test/fiber/scheduler.rb</tt>
- *
- */
-
-#if 0 /* for RDoc */
-/*
- *
- *  Document-method: Fiber::SchedulerInterface#close
- *
- *  Called when the current thread exits. The scheduler is expected to implement this
- *  method in order to allow all waiting fibers to finalize their execution.
- *
- *  The suggested pattern is to implement the main event loop in the #close method.
- *
- */
-static VALUE
-rb_fiber_scheduler_interface_close(VALUE self)
-{
-}
-
-/*
- *  Document-method: SchedulerInterface#process_wait
- *  call-seq: process_wait(pid, flags)
- *
- *  Invoked by Process::Status.wait in order to wait for a specified process.
- *  See that method description for arguments description.
- *
- *  Suggested minimal implementation:
- *
- *      Thread.new do
- *        Process::Status.wait(pid, flags)
- *      end.value
- *
- *  This hook is optional: if it is not present in the current scheduler,
- *  Process::Status.wait will behave as a blocking method.
- *
- *  Expected to return a Process::Status instance.
- */
-static VALUE
-rb_fiber_scheduler_interface_process_wait(VALUE self)
-{
-}
-
-/*
- *  Document-method: SchedulerInterface#io_wait
- *  call-seq: io_wait(io, events, timeout)
- *
- *  Invoked by IO#wait, IO#wait_readable, IO#wait_writable to ask whether the
- *  specified descriptor is ready for specified events within
- *  the specified +timeout+.
- *
- *  +events+ is a bit mask of <tt>IO::READABLE</tt>, <tt>IO::WRITABLE</tt>, and
- *  <tt>IO::PRIORITY</tt>.
- *
- *  Suggested implementation should register which Fiber is waiting for which
- *  resources and immediately calling Fiber.yield to pass control to other
- *  fibers. Then, in the #close method, the scheduler might dispatch all the
- *  I/O resources to fibers waiting for it.
- *
- *  Expected to return the subset of events that are ready immediately.
- *
- */
-static VALUE
-rb_fiber_scheduler_interface_io_wait(VALUE self)
-{
-}
-
-/*
- *  Document-method: SchedulerInterface#io_read
- *  call-seq: io_read(io, buffer, length) -> read length or -errno
- *
- *  Invoked by IO#read to read +length+ bytes from +io+ into a specified
- *  +buffer+ (see IO::Buffer).
- *
- *  The +length+ argument is the "minimum length to be read".
- *  If the IO buffer size is 8KiB, but the +length+ is +1024+ (1KiB), up to
- *  8KiB might be read, but at least 1KiB will be.
- *  Generally, the only case where less data than +length+ will be read is if
- *  there is an error reading the data.
- *
- *  Specifying a +length+ of 0 is valid and means try reading at least once
- *  and return any available data.
- *
- *  Suggested implementation should try to read from +io+ in a non-blocking
- *  manner and call #io_wait if the +io+ is not ready (which will yield control
- *  to other fibers).
- *
- *  See IO::Buffer for an interface available to return data.
- *
- *  Expected to return number of bytes read, or, in case of an error, <tt>-errno</tt>
- *  (negated number corresponding to system's error code).
- *
- *  The method should be considered _experimental_.
- */
-static VALUE
-rb_fiber_scheduler_interface_io_read(VALUE self)
-{
-}
-
-/*
- *  Document-method: SchedulerInterface#io_write
- *  call-seq: io_write(io, buffer, length) -> written length or -errno
- *
- *  Invoked by IO#write to write +length+ bytes to +io+ from
- *  from a specified +buffer+ (see IO::Buffer).
- *
- *  The +length+ argument is the "(minimum) length to be written".
- *  If the IO buffer size is 8KiB, but the +length+ specified is 1024 (1KiB),
- *  at most 8KiB will be written, but at least 1KiB will be.
- *  Generally, the only case where less data than +length+ will be written is if
- *  there is an error writing the data.
- *
- *  Specifying a +length+ of 0 is valid and means try writing at least once,
- *  as much data as possible.
- *
- *  Suggested implementation should try to write to +io+ in a non-blocking
- *  manner and call #io_wait if the +io+ is not ready (which will yield control
- *  to other fibers).
- *
- *  See IO::Buffer for an interface available to get data from buffer efficiently.
- *
- *  Expected to return number of bytes written, or, in case of an error, <tt>-errno</tt>
- *  (negated number corresponding to system's error code).
- *
- *  The method should be considered _experimental_.
- */
-static VALUE
-rb_fiber_scheduler_interface_io_write(VALUE self)
-{
-}
-
-/*
- *  Document-method: SchedulerInterface#kernel_sleep
- *  call-seq: kernel_sleep(duration = nil)
- *
- *  Invoked by Kernel#sleep and Mutex#sleep and is expected to provide
- *  an implementation of sleeping in a non-blocking way. Implementation might
- *  register the current fiber in some list of "which fiber wait until what
- *  moment", call Fiber.yield to pass control, and then in #close resume
- *  the fibers whose wait period has elapsed.
- *
- */
-static VALUE
-rb_fiber_scheduler_interface_kernel_sleep(VALUE self)
-{
-}
-
-/*
- *  Document-method: SchedulerInterface#address_resolve
- *  call-seq: address_resolve(hostname) -> array_of_strings or nil
- *
- *  Invoked by any method that performs a non-reverse DNS lookup. The most
- *  notable method is Addrinfo.getaddrinfo, but there are many other.
- *
- *  The method is expected to return an array of strings corresponding to ip
- *  addresses the +hostname+ is resolved to, or +nil+ if it can not be resolved.
- *
- *  Fairly exhaustive list of all possible call-sites:
- *
- *  - Addrinfo.getaddrinfo
- *  - Addrinfo.tcp
- *  - Addrinfo.udp
- *  - Addrinfo.ip
- *  - Addrinfo.new
- *  - Addrinfo.marshal_load
- *  - SOCKSSocket.new
- *  - TCPServer.new
- *  - TCPSocket.new
- *  - IPSocket.getaddress
- *  - TCPSocket.gethostbyname
- *  - UDPSocket#connect
- *  - UDPSocket#bind
- *  - UDPSocket#send
- *  - Socket.getaddrinfo
- *  - Socket.gethostbyname
- *  - Socket.pack_sockaddr_in
- *  - Socket.sockaddr_in
- *  - Socket.unpack_sockaddr_in
- */
-static VALUE
-rb_fiber_scheduler_interface_address_resolve(VALUE self)
-{
-}
-
-/*
- *  Document-method: SchedulerInterface#timeout_after
- *  call-seq: timeout_after(duration, exception_class, *exception_arguments, &block) -> result of block
- *
- *  Invoked by Timeout.timeout to execute the given +block+ within the given
- *  +duration+. It can also be invoked directly by the scheduler or user code.
- *
- *  Attempt to limit the execution time of a given +block+ to the given
- *  +duration+ if possible. When a non-blocking operation causes the +block+'s
- *  execution time to exceed the specified +duration+, that non-blocking
- *  operation should be interrupted by raising the specified +exception_class+
- *  constructed with the given +exception_arguments+.
- *
- *  General execution timeouts are often considered risky. This implementation
- *  will only interrupt non-blocking operations. This is by design because it's
- *  expected that non-blocking operations can fail for a variety of
- *  unpredictable reasons, so applications should already be robust in handling
- *  these conditions and by implication timeouts.
- *
- *  However, as a result of this design, if the +block+ does not invoke any
- *  non-blocking operations, it will be impossible to interrupt it. If you
- *  desire to provide predictable points for timeouts, consider adding
- *  +sleep(0)+.
- *
- *  If the block is executed successfully, its result will be returned.
- *
- *  The exception will typically be raised using Fiber#raise.
- */
-static VALUE
-rb_fiber_scheduler_interface_timeout_after(VALUE self)
-{
-}
-
-/*
- *  Document-method: SchedulerInterface#block
- *  call-seq: block(blocker, timeout = nil)
- *
- *  Invoked by methods like Thread.join, and by Mutex, to signify that current
- *  Fiber is blocked until further notice (e.g. #unblock) or until +timeout+ has
- *  elapsed.
- *
- *  +blocker+ is what we are waiting on, informational only (for debugging and
- *  logging). There are no guarantee about its value.
- *
- *  Expected to return boolean, specifying whether the blocking operation was
- *  successful or not.
- */
-static VALUE
-rb_fiber_scheduler_interface_block(VALUE self)
-{
-}
-
-/*
- *  Document-method: SchedulerInterface#unblock
- *  call-seq: unblock(blocker, fiber)
- *
- *  Invoked to wake up Fiber previously blocked with #block (for example, Mutex#lock
- *  calls #block and Mutex#unlock calls #unblock). The scheduler should use
- *  the +fiber+ parameter to understand which fiber is unblocked.
- *
- *  +blocker+ is what was awaited for, but it is informational only (for debugging
- *  and logging), and it is not guaranteed to be the same value as the +blocker+ for
- *  #block.
- *
- */
-static VALUE
-rb_fiber_scheduler_interface_unblock(VALUE self)
-{
-}
-
-/*
- *  Document-method: SchedulerInterface#fiber
- *  call-seq: fiber(&block)
- *
- *  Implementation of the Fiber.schedule. The method is <em>expected</em> to immediately
- *  run the given block of code in a separate non-blocking fiber, and to return that Fiber.
- *
- *  Minimal suggested implementation is:
- *
- *     def fiber(&block)
- *       fiber = Fiber.new(blocking: false, &block)
- *       fiber.resume
- *       fiber
- *     end
- */
-static VALUE
-rb_fiber_scheduler_interface_fiber(VALUE self)
-{
-}
-#endif
-
 void
 Init_Cont(void)
 {
@@ -3237,6 +3361,7 @@ Init_Cont(void)
 
     fiber_initialize_keywords[0] = rb_intern_const("blocking");
     fiber_initialize_keywords[1] = rb_intern_const("pool");
+    fiber_initialize_keywords[2] = rb_intern_const("storage");
 
     const char *fiber_shared_fiber_pool_free_stacks = getenv("RUBY_SHARED_FIBER_POOL_FREE_STACKS");
     if (fiber_shared_fiber_pool_free_stacks) {
@@ -3248,8 +3373,14 @@ Init_Cont(void)
     rb_eFiberError = rb_define_class("FiberError", rb_eStandardError);
     rb_define_singleton_method(rb_cFiber, "yield", rb_fiber_s_yield, -1);
     rb_define_singleton_method(rb_cFiber, "current", rb_fiber_s_current, 0);
+    rb_define_singleton_method(rb_cFiber, "blocking", rb_fiber_blocking, 0);
+    rb_define_singleton_method(rb_cFiber, "[]", rb_fiber_storage_aref, 1);
+    rb_define_singleton_method(rb_cFiber, "[]=", rb_fiber_storage_aset, 2);
+
     rb_define_method(rb_cFiber, "initialize", rb_fiber_initialize, -1);
     rb_define_method(rb_cFiber, "blocking?", rb_fiber_blocking_p, 0);
+    rb_define_method(rb_cFiber, "storage", rb_fiber_storage_get, 0);
+    rb_define_method(rb_cFiber, "storage=", rb_fiber_storage_set, 1);
     rb_define_method(rb_cFiber, "resume", rb_fiber_m_resume, -1);
     rb_define_method(rb_cFiber, "raise", rb_fiber_m_raise, -1);
     rb_define_method(rb_cFiber, "backtrace", rb_fiber_backtrace, -1);
@@ -3266,21 +3397,6 @@ Init_Cont(void)
 
     rb_define_singleton_method(rb_cFiber, "schedule", rb_fiber_s_schedule, -1);
 
-#if 0 /* for RDoc */
-    rb_cFiberScheduler = rb_define_class_under(rb_cFiber, "SchedulerInterface", rb_cObject);
-    rb_define_method(rb_cFiberScheduler, "close", rb_fiber_scheduler_interface_close, 0);
-    rb_define_method(rb_cFiberScheduler, "process_wait", rb_fiber_scheduler_interface_process_wait, 0);
-    rb_define_method(rb_cFiberScheduler, "io_wait", rb_fiber_scheduler_interface_io_wait, 0);
-    rb_define_method(rb_cFiberScheduler, "io_read", rb_fiber_scheduler_interface_io_read, 0);
-    rb_define_method(rb_cFiberScheduler, "io_write", rb_fiber_scheduler_interface_io_write, 0);
-    rb_define_method(rb_cFiberScheduler, "kernel_sleep", rb_fiber_scheduler_interface_kernel_sleep, 0);
-    rb_define_method(rb_cFiberScheduler, "address_resolve", rb_fiber_scheduler_interface_address_resolve, 0);
-    rb_define_method(rb_cFiberScheduler, "timeout_after", rb_fiber_scheduler_interface_timeout_after, 0);
-    rb_define_method(rb_cFiberScheduler, "block", rb_fiber_scheduler_interface_block, 0);
-    rb_define_method(rb_cFiberScheduler, "unblock", rb_fiber_scheduler_interface_unblock, 0);
-    rb_define_method(rb_cFiberScheduler, "fiber", rb_fiber_scheduler_interface_fiber, 0);
-#endif
-
 #ifdef RB_EXPERIMENTAL_FIBER_POOL
     rb_cFiberPool = rb_define_class_under(rb_cFiber, "Pool", rb_cObject);
     rb_define_alloc_func(rb_cFiberPool, fiber_pool_alloc);
diff --git a/coroutine/amd64/Context.h b/coroutine/amd64/Context.h
index f626a47225..44daa4e01a 100644
--- a/coroutine/amd64/Context.h
+++ b/coroutine/amd64/Context.h
@@ -19,10 +19,29 @@
 
 enum {COROUTINE_REGISTERS = 6};
 
+#if defined(__SANITIZE_ADDRESS__)
+    #define COROUTINE_SANITIZE_ADDRESS
+#elif defined(__has_feature)
+    #if __has_feature(address_sanitizer)
+        #define COROUTINE_SANITIZE_ADDRESS
+    #endif
+#endif
+
+#if defined(COROUTINE_SANITIZE_ADDRESS)
+#include <sanitizer/common_interface_defs.h>
+#include <sanitizer/asan_interface.h>
+#endif
+
 struct coroutine_context
 {
     void **stack_pointer;
     void *argument;
+
+#if defined(COROUTINE_SANITIZE_ADDRESS)
+    void *fake_stack;
+    void *stack_base;
+    size_t stack_size;
+#endif
 };
 
 typedef COROUTINE(* coroutine_start)(struct coroutine_context *from, struct coroutine_context *self);
@@ -39,6 +58,12 @@ static inline void coroutine_initialize(
 ) {
     assert(start && stack && size >= 1024);
 
+#if defined(COROUTINE_SANITIZE_ADDRESS)
+    context->fake_stack = NULL;
+    context->stack_base = stack;
+    context->stack_size = size;
+#endif
+
     // Stack grows down. Force 16-byte alignment.
     char * top = (char*)stack + size;
     context->stack_pointer = (void**)((uintptr_t)top & ~0xF);
diff --git a/coroutine/arm64/Context.h b/coroutine/arm64/Context.h
index dbc6ac94fb..1472621f48 100644
--- a/coroutine/arm64/Context.h
+++ b/coroutine/arm64/Context.h
@@ -19,10 +19,29 @@
 
 enum {COROUTINE_REGISTERS = 0xb0 / 8};
 
+#if defined(__SANITIZE_ADDRESS__)
+    #define COROUTINE_SANITIZE_ADDRESS
+#elif defined(__has_feature)
+    #if __has_feature(address_sanitizer)
+        #define COROUTINE_SANITIZE_ADDRESS
+    #endif
+#endif
+
+#if defined(COROUTINE_SANITIZE_ADDRESS)
+#include <sanitizer/common_interface_defs.h>
+#include <sanitizer/asan_interface.h>
+#endif
+
 struct coroutine_context
 {
     void **stack_pointer;
     void *argument;
+
+#if defined(COROUTINE_SANITIZE_ADDRESS)
+    void *fake_stack;
+    void *stack_base;
+    size_t stack_size;
+#endif
 };
 
 typedef COROUTINE(* coroutine_start)(struct coroutine_context *from, struct coroutine_context *self);
@@ -39,6 +58,12 @@ static inline void coroutine_initialize(
 ) {
     assert(start && stack && size >= 1024);
 
+#if defined(COROUTINE_SANITIZE_ADDRESS)
+    context->fake_stack = NULL;
+    context->stack_base = stack;
+    context->stack_size = size;
+#endif
+
     // Stack grows down. Force 16-byte alignment.
     char * top = (char*)stack + size;
     context->stack_pointer = (void**)((uintptr_t)top & ~0xF);
diff --git a/coroutine/asyncify/Context.h b/coroutine/asyncify/Context.h
index 7dba829a1d..71791a4004 100644
--- a/coroutine/asyncify/Context.h
+++ b/coroutine/asyncify/Context.h
@@ -13,6 +13,7 @@
 
 #include <stddef.h>
 #include <stdio.h>
+#include <stdint.h>
 #include "wasm/asyncify.h"
 #include "wasm/machine.h"
 #include "wasm/fiber.h"
@@ -47,10 +48,13 @@ static inline void coroutine_initialize_main(struct coroutine_context * context)
 
 static inline void coroutine_initialize(struct coroutine_context *context, coroutine_start start, void *stack, size_t size)
 {
-    if (ASYNCIFY_CORO_DEBUG) fprintf(stderr, "[%s] entry (context = %p, stack = %p ... %p)\n", __func__, context, stack, (char *)stack + size);
+    // Linear stack pointer must be always aligned down to 16 bytes.
+    // https://github.com/WebAssembly/tool-conventions/blob/c74267a5897c1bdc9aa60adeaf41816387d3cd12/BasicCABI.md#the-linear-stack
+    uintptr_t sp = ((uintptr_t)stack + size) & ~0xF;
+    if (ASYNCIFY_CORO_DEBUG) fprintf(stderr, "[%s] entry (context = %p, stack = %p ... %p)\n", __func__, context, stack, (char *)sp);
     rb_wasm_init_context(&context->fc, coroutine_trampoline, start, context);
     // record the initial stack pointer position to restore it after resumption
-    context->current_sp = (char *)stack + size;
+    context->current_sp = (char *)sp;
     context->stack_base = stack;
     context->size = size;
 }
diff --git a/coroutine/ppc/Context.S b/coroutine/ppc/Context.S
new file mode 100644
index 0000000000..cdda93e179
--- /dev/null
+++ b/coroutine/ppc/Context.S
@@ -0,0 +1,90 @@
+; Based on the code by Samuel Williams. Created by Sergey Fedorov on 04/06/2022.
+; Credits to Samuel Williams, Rei Odaira and Iain Sandoe. Errors, if any, are mine.
+; Some relevant examples: https://github.com/gcc-mirror/gcc/blob/master/libphobos/libdruntime/config/powerpc/switchcontext.S
+; https://github.com/gcc-mirror/gcc/blob/master/libgcc/config/rs6000/darwin-gpsave.S
+; https://www.ibm.com/docs/en/aix/7.2?topic=epilogs-saving-gprs-only
+; ppc32 version may be re-written compactly with stmw/lwm, but the code wonʼt be faster, see: https://github.com/ruby/ruby/pull/5927#issuecomment-1139730541
+
+; Notice that this code is only for Darwin (macOS). Darwin ABI differs from AIX and ELF.
+; To add support for AIX, *BSD or *Linux, please make separate implementations.
+
+#define TOKEN_PASTE(x,y) x##y
+#define PREFIXED_SYMBOL(prefix,name) TOKEN_PASTE(prefix,name)
+
+.machine ppc7400 ; = G4, Rosetta
+.text
+
+.globl PREFIXED_SYMBOL(SYMBOL_PREFIX,coroutine_transfer)
+.align 2
+
+PREFIXED_SYMBOL(SYMBOL_PREFIX,coroutine_transfer):
+	; Make space on the stack for caller registers
+	; (Should we rather use red zone? See libphobos example.)
+	subi r1,r1,80
+
+	; Get LR
+	mflr r0
+
+	; Save caller registers
+	stw r31,0(r1)
+	stw r30,4(r1)
+	stw r29,8(r1)
+	stw r28,12(r1)
+	stw r27,16(r1)
+	stw r26,20(r1)
+	stw r25,24(r1)
+	stw r24,28(r1)
+	stw r23,32(r1)
+	stw r22,36(r1)
+	stw r21,40(r1)
+	stw r20,44(r1)
+	stw r19,48(r1)
+	stw r18,52(r1)
+	stw r17,56(r1)
+	stw r16,60(r1)
+	stw r15,64(r1)
+	stw r14,68(r1)
+	stw r13,72(r1)
+
+	; Save return address
+	; Possibly should rather be saved into linkage area, see libphobos and IBM docs
+	stw r0,76(r1)
+
+	; Save stack pointer to first argument
+	stw r1,0(r3)
+
+	; Load stack pointer from second argument
+	lwz r1,0(r4)
+
+	; Load return address
+	lwz r0,76(r1)
+
+	; Restore caller registers
+	lwz r13,72(r1)
+	lwz r14,68(r1)
+	lwz r15,64(r1)
+	lwz r16,60(r1)
+	lwz r17,56(r1)
+	lwz r18,52(r1)
+	lwz r19,48(r1)
+	lwz r20,44(r1)
+	lwz r21,40(r1)
+	lwz r22,36(r1)
+	lwz r23,32(r1)
+	lwz r24,28(r1)
+	lwz r25,24(r1)
+	lwz r26,20(r1)
+	lwz r27,16(r1)
+	lwz r28,12(r1)
+	lwz r29,8(r1)
+	lwz r30,4(r1)
+	lwz r31,0(r1)
+
+	; Set LR
+	mtlr r0
+
+	; Pop stack frame
+	addi r1,r1,80
+
+	; Jump to return address
+	blr
diff --git a/coroutine/ppc/Context.h b/coroutine/ppc/Context.h
new file mode 100644
index 0000000000..1fce112579
--- /dev/null
+++ b/coroutine/ppc/Context.h
@@ -0,0 +1,58 @@
+#ifndef COROUTINE_PPC_CONTEXT_H
+#define COROUTINE_PPC_CONTEXT_H 1
+
+#pragma once
+
+#include <assert.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+
+#define COROUTINE __attribute__((noreturn)) void
+#define COROUTINE_LIMITED_ADDRESS_SPACE
+
+enum {
+  COROUTINE_REGISTERS =
+  20  /* 19 general purpose registers (r13–r31) and 1 return address */
+  + 4  /* space for fiber_entry() to store the link register */
+};
+
+struct coroutine_context
+{
+    void **stack_pointer;
+    void *argument;
+};
+
+typedef COROUTINE(* coroutine_start)(struct coroutine_context *from, struct coroutine_context *self);
+
+static inline void coroutine_initialize_main(struct coroutine_context * context) {
+    context->stack_pointer = NULL;
+}
+
+static inline void coroutine_initialize(
+    struct coroutine_context *context,
+    coroutine_start start,
+    void *stack,
+    size_t size
+) {
+    assert(start && stack && size >= 1024);
+
+    // Stack grows down. Force 16-byte alignment.
+    char * top = (char*)stack + size;
+    context->stack_pointer = (void**)((uintptr_t)top & ~0xF);
+
+    context->stack_pointer -= COROUTINE_REGISTERS;
+    memset(context->stack_pointer, 0, sizeof(void*) * COROUTINE_REGISTERS);
+
+    /* Skip a global prologue that sets the TOC register */
+    context->stack_pointer[19] = ((char*)start) + 8;
+}
+
+struct coroutine_context * coroutine_transfer(struct coroutine_context * current, struct coroutine_context * target);
+
+static inline void coroutine_destroy(struct coroutine_context * context)
+{
+    context->stack_pointer = NULL;
+}
+
+#endif /* COROUTINE_PPC_CONTEXT_H */
diff --git a/coroutine/ppc64/Context.S b/coroutine/ppc64/Context.S
new file mode 100644
index 0000000000..f8561e0e7d
--- /dev/null
+++ b/coroutine/ppc64/Context.S
@@ -0,0 +1,89 @@
+; Based on the code by Samuel Williams. Created by Sergey Fedorov on 04/06/2022.
+; Credits to Samuel Williams, Rei Odaira and Iain Sandoe. Errors, if any, are mine.
+; Some relevant examples: https://github.com/gcc-mirror/gcc/blob/master/libphobos/libdruntime/config/powerpc/switchcontext.S
+; https://github.com/gcc-mirror/gcc/blob/master/libgcc/config/rs6000/darwin-gpsave.S
+; https://www.ibm.com/docs/en/aix/7.2?topic=epilogs-saving-gprs-only
+
+; Notice that this code is only for Darwin (macOS). Darwin ABI differs from AIX and ELF.
+; To add support for AIX, *BSD or *Linux, please make separate implementations.
+
+#define TOKEN_PASTE(x,y) x##y
+#define PREFIXED_SYMBOL(prefix,name) TOKEN_PASTE(prefix,name)
+
+.machine ppc64 ; = G5
+.text
+
+.globl PREFIXED_SYMBOL(SYMBOL_PREFIX,coroutine_transfer)
+.align 2
+
+PREFIXED_SYMBOL(SYMBOL_PREFIX,coroutine_transfer):
+	; Make space on the stack for caller registers
+	; (Should we rather use red zone? See libphobos example.)
+	subi r1,r1,160
+
+	; Get LR
+	mflr r0
+
+	; Save caller registers
+	std r31,0(r1)
+	std r30,8(r1)
+	std r29,16(r1)
+	std r28,24(r1)
+	std r27,32(r1)
+	std r26,40(r1)
+	std r25,48(r1)
+	std r24,56(r1)
+	std r23,64(r1)
+	std r22,72(r1)
+	std r21,80(r1)
+	std r20,88(r1)
+	std r19,96(r1)
+	std r18,104(r1)
+	std r17,112(r1)
+	std r16,120(r1)
+	std r15,128(r1)
+	std r14,136(r1)
+	std r13,144(r1)
+
+	; Save return address
+	; Possibly should rather be saved into linkage area, see libphobos and IBM docs
+	std r0,152(r1)
+
+	; Save stack pointer to first argument
+	std r1,0(r3)
+
+	; Load stack pointer from second argument
+	ld r1,0(r4)
+
+	; Load return address
+	ld r0,152(r1)
+
+	; Restore caller registers
+	ld r13,144(r1)
+	ld r14,136(r1)
+	ld r15,128(r1)
+	ld r16,120(r1)
+	ld r17,112(r1)
+	ld r18,104(r1)
+	ld r19,96(r1)
+	ld r20,88(r1)
+	ld r21,80(r1)
+	ld r22,72(r1)
+	ld r23,64(r1)
+	ld r24,56(r1)
+	ld r25,48(r1)
+	ld r26,40(r1)
+	ld r27,32(r1)
+	ld r28,24(r1)
+	ld r29,16(r1)
+	ld r30,8(r1)
+	ld r31,0(r1)
+
+	; Set LR
+	mtlr r0
+
+	; Pop stack frame
+	addi r1,r1,160
+
+	; Jump to return address
+	blr
diff --git a/coroutine/ppc64/Context.h b/coroutine/ppc64/Context.h
new file mode 100644
index 0000000000..3e6f77f55a
--- /dev/null
+++ b/coroutine/ppc64/Context.h
@@ -0,0 +1,57 @@
+#ifndef COROUTINE_PPC64_CONTEXT_H
+#define COROUTINE_PPC64_CONTEXT_H 1
+
+#pragma once
+
+#include <assert.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+
+#define COROUTINE __attribute__((noreturn)) void
+
+enum {
+  COROUTINE_REGISTERS =
+  20  /* 19 general purpose registers (r13–r31) and 1 return address */
+  + 4  /* space for fiber_entry() to store the link register */
+};
+
+struct coroutine_context
+{
+    void **stack_pointer;
+    void *argument;
+};
+
+typedef COROUTINE(* coroutine_start)(struct coroutine_context *from, struct coroutine_context *self);
+
+static inline void coroutine_initialize_main(struct coroutine_context * context) {
+    context->stack_pointer = NULL;
+}
+
+static inline void coroutine_initialize(
+    struct coroutine_context *context,
+    coroutine_start start,
+    void *stack,
+    size_t size
+) {
+    assert(start && stack && size >= 1024);
+
+    // Stack grows down. Force 16-byte alignment.
+    char * top = (char*)stack + size;
+    context->stack_pointer = (void**)((uintptr_t)top & ~0xF);
+
+    context->stack_pointer -= COROUTINE_REGISTERS;
+    memset(context->stack_pointer, 0, sizeof(void*) * COROUTINE_REGISTERS);
+
+    /* Skip a global prologue that sets the TOC register */
+    context->stack_pointer[19] = ((char*)start) + 8;
+}
+
+struct coroutine_context * coroutine_transfer(struct coroutine_context * current, struct coroutine_context * target);
+
+static inline void coroutine_destroy(struct coroutine_context * context)
+{
+    context->stack_pointer = NULL;
+}
+
+#endif /* COROUTINE_PPC64_CONTEXT_H */
diff --git a/coroutine/universal/Context.S b/coroutine/universal/Context.S
index 0fd8c01e7f..11c80a7927 100644
--- a/coroutine/universal/Context.S
+++ b/coroutine/universal/Context.S
@@ -3,7 +3,11 @@
 # include "coroutine/amd64/Context.S"
 #elif defined __i386__
 # include "coroutine/x86/Context.S"
-#elif defined __ppc64__
+#elif defined __ppc__
+# include "coroutine/ppc/Context.S"
+#elif defined __ppc64__ && defined(WORDS_BIGENDIAN)
+# include "coroutine/ppc64/Context.S"
+#elif defined __ppc64__ && !defined(WORDS_BIGENDIAN)
 # include "coroutine/ppc64le/Context.S"
 #elif defined __arm64__
 # include "coroutine/arm64/Context.S"
diff --git a/coroutine/universal/Context.h b/coroutine/universal/Context.h
index 9a2ef425db..ec4d2f484a 100644
--- a/coroutine/universal/Context.h
+++ b/coroutine/universal/Context.h
@@ -6,7 +6,11 @@
 # include "coroutine/amd64/Context.h"
 #elif defined __i386__
 # include "coroutine/x86/Context.h"
-#elif defined __ppc64__
+#elif defined __ppc__
+# include "coroutine/ppc/Context.h"
+#elif defined __ppc64__ && defined(WORDS_BIGENDIAN)
+# include "coroutine/ppc64/Context.h"
+#elif defined __ppc64__ && !defined(WORDS_BIGENDIAN)
 # include "coroutine/ppc64le/Context.h"
 #elif defined __arm64__
 # include "coroutine/arm64/Context.h"
diff --git a/cygwin/GNUmakefile.in b/cygwin/GNUmakefile.in
index b13c3d9c8a..f342d2fcf7 100644
--- a/cygwin/GNUmakefile.in
+++ b/cygwin/GNUmakefile.in
@@ -2,15 +2,17 @@ gnumake = yes
 
 include Makefile
 
-ENABLE_SHARED=@ENABLE_SHARED@
-DLLWRAP = @DLLWRAP@ --target=@target_os@ --driver-name="$(CC)"
+MUNICODE_FLAG := $(if $(filter mingw%,$(target_os)),-municode)
+override EXE_LDFLAGS += $(MUNICODE_FLAG)
+
+DLLWRAP = @DLLWRAP@ --target=$(target_os) --driver-name="$(CC)"
 windres-cpp := $(CPP) -xc
 windres-cpp := --preprocessor=$(firstword $(windres-cpp)) \
 	$(addprefix --preprocessor-arg=,$(wordlist 2,$(words $(windres-cpp)),$(windres-cpp)))
 WINDRES = @WINDRES@ $(windres-cpp) -DRC_INVOKED
 STRIP = @STRIP@
 
-ifeq (@target_os@,cygwin)
+ifeq ($(target_os),cygwin)
   DLL_BASE_NAME := $(LIBRUBY_SO:.dll=)
 else
   DLL_BASE_NAME := $(RUBY_SO_NAME)
@@ -38,7 +40,7 @@ WPROGRAM = $(RUBYW_INSTALL_NAME)$(EXEEXT)
 
 include $(srcdir)/template/GNUmakefile.in
 
-SOLIBS := $(DLL_BASE_NAME).res.@OBJEXT@ $(SOLIBS)
+SOLIBS := $(DLL_BASE_NAME).res.$(OBJEXT) $(SOLIBS)
 override EXTOBJS += $(if $(filter-out $(RUBYW_INSTALL_NAME),$(@:$(EXEEXT)=)),$(RUBY_INSTALL_NAME),$(@:$(EXEEXT)=)).res.$(OBJEXT)
 RCFILES = $(RUBY_INSTALL_NAME).rc $(RUBYW_INSTALL_NAME).rc $(DLL_BASE_NAME).rc
 RUBYDEF = $(DLL_BASE_NAME).def
@@ -47,26 +49,26 @@ ruby: $(PROGRAM)
 rubyw: $(WPROGRAM)
 
 $(LIBRUBY): $(RUBY_EXP) $(LIBRUBY_SO)
-$(RUBY_EXP) $(LIBRUBY_SO): $(DLL_BASE_NAME).res.@OBJEXT@
+$(RUBY_EXP) $(LIBRUBY_SO): $(DLL_BASE_NAME).res.$(OBJEXT)
 
-%.res.@OBJEXT@: %.rc
+%.res.$(OBJEXT): %.rc
 	$(ECHO) compiling $@
 	$(Q) $(WINDRES) --include-dir . --include-dir $(<D) --include-dir $(srcdir)/win32 $< $@
 
-%.rc: $(RBCONFIG) $(srcdir)/revision.h $(srcdir)/win32/resource.rb
+%.rc: $(BOOTSTRAPRUBY_FAKE) $(RBCONFIG) $(srcdir)/revision.h $(srcdir)/win32/resource.rb
 	$(ECHO) generating $@
-	$(Q) $(MINIRUBY) $(srcdir)/win32/resource.rb \
+	$(Q) $(BOOTSTRAPRUBY_COMMAND) $(srcdir)/win32/resource.rb \
 	  -ruby_name=$(RUBY_INSTALL_NAME) -rubyw_name=$(RUBYW_INSTALL_NAME) \
 	  -so_name=$(DLL_BASE_NAME) -output=$(*F) \
 	  . $(icondirs) $(srcdir)/win32
 
-$(PROGRAM): $(RUBY_INSTALL_NAME).res.@OBJEXT@
-$(WPROGRAM): $(RUBYW_INSTALL_NAME).res.@OBJEXT@
+$(PROGRAM): $(RUBY_INSTALL_NAME).res.$(OBJEXT)
+$(WPROGRAM): $(RUBYW_INSTALL_NAME).res.$(OBJEXT)
 	@rm -f $@
 	$(ECHO) linking $@
-	$(Q) $(PURIFY) $(CC) -mwindows -e $(SYMBOL_PREFIX)mainCRTStartup $(LDFLAGS) $(XLDFLAGS) \
+	$(Q) $(PURIFY) $(CC) $(MUNICODE_FLAG) -mwindows -e $(SYMBOL_PREFIX)mainCRTStartup $(LDFLAGS) $(XLDFLAGS) \
 	  $(MAINOBJ) $(EXTOBJS) $(LIBRUBYARG) $(LIBS) -o $@
-$(STUBPROGRAM): $(RUBY_INSTALL_NAME).res.@OBJEXT@
+$(STUBPROGRAM): $(RUBY_INSTALL_NAME).res.$(OBJEXT)
 
 $(RUBY_EXP): $(LIBRUBY_A)
 	$(ECHO) creating $@
@@ -78,7 +80,7 @@ $(RUBY_EXP): $(LIBRUBY_A)
 
 GNUmakefile:	$(srcdir)/cygwin/GNUmakefile.in
 
-ifeq (@target_os@,mingw32)
+ifeq ($(target_os),mingw32)
 $(OBJS) $(MAINOBJ): win32.h
 
 dir.$(OBJEXT) win32/win32.$(OBJEXT): win32/dir.h
@@ -89,16 +91,17 @@ MSYS2_ARG_CONV_EXCL_PARAM = --exclude=;--name=
 yes-test-ruby:	 export MSYS2_ARG_CONV_EXCL=$(MSYS2_ARG_CONV_EXCL_PARAM)
 yes-test-all:	 export MSYS2_ARG_CONV_EXCL=$(MSYS2_ARG_CONV_EXCL_PARAM)
 yes-test-almost: export MSYS2_ARG_CONV_EXCL=$(MSYS2_ARG_CONV_EXCL_PARAM)
+test/% spec/%/ spec/%_spec.rb: export MSYS2_ARG_CONV_EXCL=$(MSYS2_ARG_CONV_EXCL_PARAM)
 
 endif
 
 $(LIBRUBY_SO): $(RUBYDEF)
 
-$(RUBYDEF): $(LIBRUBY_A) $(PREP) $(RBCONFIG)
+$(RUBYDEF): $(LIBRUBY_A) $(PREP) $(BOOTSTRAPRUBY_FAKE) $(RBCONFIG)
 	$(ECHO) generating $@
-	$(Q) $(MINIRUBY) $(srcdir)/win32/mkexports.rb -output=$@ $(LIBRUBY_A)
+	$(Q) $(BOOTSTRAPRUBY_COMMAND) $(srcdir)/win32/mkexports.rb -output=$@ $(LIBRUBY_A)
 
 clean-local::
 	@$(RM) $(RUBYDEF)
-	@$(RM) $(RUBY_EXP) $(RCFILES:.rc=.res.@OBJEXT@)
+	@$(RM) $(RUBY_EXP) $(RCFILES:.rc=.res.$(OBJEXT))
 	@$(RM) $(RCFILES)
diff --git a/darray.h b/darray.h
index bb8199a98c..c9a53f1e01 100644
--- a/darray.h
+++ b/darray.h
@@ -41,20 +41,9 @@
 //
 // void rb_darray_append(rb_darray(T) *ptr_to_ary, T element);
 //
-// TODO: replace this with rb_darray_append_with_gc when YJIT moves to Rust.
-//
 #define rb_darray_append(ptr_to_ary, element) do {  \
     rb_darray_ensure_space((ptr_to_ary), sizeof(**(ptr_to_ary)), \
-                           sizeof((*(ptr_to_ary))->data[0]), realloc); \
-    rb_darray_set(*(ptr_to_ary), \
-                  (*(ptr_to_ary))->meta.size, \
-                  (element)); \
-    (*(ptr_to_ary))->meta.size++; \
-} while (0)
-
-#define rb_darray_append_with_gc(ptr_to_ary, element) do {  \
-    rb_darray_ensure_space((ptr_to_ary), sizeof(**(ptr_to_ary)), \
-                           sizeof((*(ptr_to_ary))->data[0]), ruby_xrealloc); \
+                           sizeof((*(ptr_to_ary))->data[0])); \
     rb_darray_set(*(ptr_to_ary), \
                   (*(ptr_to_ary))->meta.size, \
                   (element)); \
@@ -87,22 +76,14 @@
     for (size_t idx_name = 0; idx_name < rb_darray_size(ary); ++idx_name)
 
 // Make a dynamic array of a certain size. All bytes backing the elements are set to zero.
-// Return 1 on success and 0 on failure.
 //
 // Note that NULL is a valid empty dynamic array.
 //
 // void rb_darray_make(rb_darray(T) *ptr_to_ary, size_t size);
 //
-// TODO: replace this with rb_darray_make_with_gc with YJIT moves to Rust.
-//
 #define rb_darray_make(ptr_to_ary, size) \
     rb_darray_make_impl((ptr_to_ary), size, sizeof(**(ptr_to_ary)), \
-                        sizeof((*(ptr_to_ary))->data[0]), calloc)
-
-
-#define rb_darray_make_with_gc(ptr_to_ary, size) \
-    rb_darray_make_impl((ptr_to_ary), size, sizeof(**(ptr_to_ary)), \
-                         sizeof((*(ptr_to_ary))->data[0]), ruby_xcalloc)
+                         sizeof((*(ptr_to_ary))->data[0]))
 
 #define rb_darray_data_ptr(ary) ((ary)->data)
 
@@ -136,34 +117,18 @@ rb_darray_capa(const void *ary)
 
 // Free the dynamic array.
 //
-// TODO: replace this with rb_darray_free_with_gc when YJIT moves to Rust.
-//
 static inline void
 rb_darray_free(void *ary)
 {
-    free(ary);
-}
-
-static inline void
-rb_darray_free_with_gc(void *ary)
-{
     rb_darray_meta_t *meta = ary;
     ruby_sized_xfree(ary, meta->capa);
 }
 
-// Internal function. Calculate buffer size on malloc heap.
-static inline size_t
-rb_darray_buffer_size(size_t capacity, size_t header_size, size_t element_size)
-{
-    if (capacity == 0) return 0;
-    return header_size + capacity * element_size;
-}
-
 // Internal function
 // Ensure there is space for one more element.
 // Note: header_size can be bigger than sizeof(rb_darray_meta_t) when T is __int128_t, for example.
 static inline void
-rb_darray_ensure_space(void *ptr_to_ary, size_t header_size, size_t element_size, void *(*realloc_impl)(void *, size_t))
+rb_darray_ensure_space(void *ptr_to_ary, size_t header_size, size_t element_size)
 {
     rb_darray_meta_t **ptr_to_ptr_to_meta = ptr_to_ary;
     rb_darray_meta_t *meta = *ptr_to_ptr_to_meta;
@@ -173,18 +138,9 @@ rb_darray_ensure_space(void *ptr_to_ary, size_t header_size, size_t element_size
     // Double the capacity
     size_t new_capa = current_capa == 0 ? 1 : current_capa * 2;
 
-    // Calculate new buffer size
-    size_t current_buffer_size = rb_darray_buffer_size(current_capa, header_size, element_size);
-    size_t new_buffer_size = rb_darray_buffer_size(new_capa, header_size, element_size);
-    if (new_buffer_size <= current_buffer_size) {
-        rb_bug("rb_darray_ensure_space: overflow");
-    }
-
-    // TODO: replace with rb_xrealloc_mul_add(meta, new_capa, element_size, header_size);
-    rb_darray_meta_t *doubled_ary = realloc_impl(meta, new_buffer_size);
-    if (!doubled_ary) {
-        rb_bug("rb_darray_ensure_space: failed");
-    }
+    rb_darray_meta_t *doubled_ary = rb_xrealloc_mul_add(meta, new_capa, element_size, header_size);
+    // rb_xrealloc functions guarantee that NULL is not returned
+    assert(doubled_ary != NULL);
 
     if (meta == NULL) {
         // First allocation. Initialize size. On subsequence allocations
@@ -200,7 +156,7 @@ rb_darray_ensure_space(void *ptr_to_ary, size_t header_size, size_t element_size
 }
 
 static inline void
-rb_darray_make_impl(void *ptr_to_ary, size_t array_size, size_t header_size, size_t element_size, void *(*calloc_impl)(size_t, size_t))
+rb_darray_make_impl(void *ptr_to_ary, size_t array_size, size_t header_size, size_t element_size)
 {
     rb_darray_meta_t **ptr_to_ptr_to_meta = ptr_to_ary;
     if (array_size == 0) {
@@ -208,12 +164,9 @@ rb_darray_make_impl(void *ptr_to_ary, size_t array_size, size_t header_size, siz
         return;
     }
 
-    // TODO: replace with rb_xcalloc_mul_add(array_size, element_size, header_size)
-    size_t buffer_size = rb_darray_buffer_size(array_size, header_size, element_size);
-    rb_darray_meta_t *meta = calloc_impl(buffer_size, 1);
-    if (!meta) {
-        rb_bug("rb_darray_make_impl: failed");
-    }
+    rb_darray_meta_t *meta = rb_xcalloc_mul_add(array_size, element_size, header_size);
+    // rb_xcalloc functions guarantee that NULL is not returned
+    assert(meta != NULL);
 
     meta->size = array_size;
     meta->capa = array_size;
diff --git a/debug.c b/debug.c
index 95a994e63c..3dd0f71906 100644
--- a/debug.c
+++ b/debug.c
@@ -53,7 +53,9 @@ const union {
     rb_econv_result_t           econv_result;
     enum ruby_preserved_encindex encoding_index;
     enum ruby_robject_flags     robject_flags;
+#if !USE_RVARGC
     enum ruby_robject_consts    robject_consts;
+#endif
     enum ruby_rmodule_flags     rmodule_flags;
     enum ruby_rstring_flags     rstring_flags;
 #if !USE_RVARGC
@@ -62,23 +64,23 @@ const union {
     enum ruby_rarray_flags      rarray_flags;
     enum ruby_rarray_consts     rarray_consts;
     enum {
-	RUBY_FMODE_READABLE		= FMODE_READABLE,
-	RUBY_FMODE_WRITABLE		= FMODE_WRITABLE,
-	RUBY_FMODE_READWRITE		= FMODE_READWRITE,
-	RUBY_FMODE_BINMODE		= FMODE_BINMODE,
-	RUBY_FMODE_SYNC 		= FMODE_SYNC,
-	RUBY_FMODE_TTY			= FMODE_TTY,
-	RUBY_FMODE_DUPLEX		= FMODE_DUPLEX,
-	RUBY_FMODE_APPEND		= FMODE_APPEND,
-	RUBY_FMODE_CREATE		= FMODE_CREATE,
-	RUBY_FMODE_NOREVLOOKUP		= 0x00000100,
-	RUBY_FMODE_TRUNC		= FMODE_TRUNC,
-	RUBY_FMODE_TEXTMODE		= FMODE_TEXTMODE,
-	RUBY_FMODE_PREP 		= 0x00010000,
-	RUBY_FMODE_SETENC_BY_BOM	= FMODE_SETENC_BY_BOM,
-	RUBY_FMODE_UNIX 		= 0x00200000,
-	RUBY_FMODE_INET 		= 0x00400000,
-	RUBY_FMODE_INET6		= 0x00800000,
+        RUBY_FMODE_READABLE		= FMODE_READABLE,
+        RUBY_FMODE_WRITABLE		= FMODE_WRITABLE,
+        RUBY_FMODE_READWRITE		= FMODE_READWRITE,
+        RUBY_FMODE_BINMODE		= FMODE_BINMODE,
+        RUBY_FMODE_SYNC 		= FMODE_SYNC,
+        RUBY_FMODE_TTY			= FMODE_TTY,
+        RUBY_FMODE_DUPLEX		= FMODE_DUPLEX,
+        RUBY_FMODE_APPEND		= FMODE_APPEND,
+        RUBY_FMODE_CREATE		= FMODE_CREATE,
+        RUBY_FMODE_NOREVLOOKUP		= 0x00000100,
+        RUBY_FMODE_TRUNC		= FMODE_TRUNC,
+        RUBY_FMODE_TEXTMODE		= FMODE_TEXTMODE,
+        RUBY_FMODE_PREP 		= 0x00010000,
+        RUBY_FMODE_SETENC_BY_BOM	= FMODE_SETENC_BY_BOM,
+        RUBY_FMODE_UNIX 		= 0x00200000,
+        RUBY_FMODE_INET 		= 0x00400000,
+        RUBY_FMODE_INET6		= 0x00800000,
 
         RUBY_NODE_TYPESHIFT = NODE_TYPESHIFT,
         RUBY_NODE_TYPEMASK  = NODE_TYPEMASK,
@@ -86,9 +88,9 @@ const union {
         RUBY_NODE_FL_NEWLINE   = NODE_FL_NEWLINE
     } various;
     union {
-	enum imemo_type                     types;
-	enum {RUBY_IMEMO_MASK = IMEMO_MASK} mask;
-	struct RIMemo                      *ptr;
+        enum imemo_type                     types;
+        enum {RUBY_IMEMO_MASK = IMEMO_MASK} mask;
+        struct RIMemo                      *ptr;
     } imemo;
     struct RSymbol *symbol_ptr;
     enum vm_call_flag_bits vm_call_flags;
@@ -100,9 +102,9 @@ int
 ruby_debug_print_indent(int level, int debug_level, int indent_level)
 {
     if (level < debug_level) {
-	fprintf(stderr, "%*s", indent_level, "");
-	fflush(stderr);
-	return TRUE;
+        fprintf(stderr, "%*s", indent_level, "");
+        fflush(stderr);
+        return TRUE;
     }
     return FALSE;
 }
@@ -122,11 +124,11 @@ VALUE
 ruby_debug_print_value(int level, int debug_level, const char *header, VALUE obj)
 {
     if (level < debug_level) {
-	char buff[0x100];
-	rb_raw_obj_info(buff, 0x100, obj);
+        char buff[0x100];
+        rb_raw_obj_info(buff, 0x100, obj);
 
-	fprintf(stderr, "DBG> %s: %s\n", header, buff);
-	fflush(stderr);
+        fprintf(stderr, "DBG> %s: %s\n", header, buff);
+        fflush(stderr);
     }
     return obj;
 }
@@ -141,8 +143,8 @@ ID
 ruby_debug_print_id(int level, int debug_level, const char *header, ID id)
 {
     if (level < debug_level) {
-	fprintf(stderr, "DBG> %s: %s\n", header, rb_id2name(id));
-	fflush(stderr);
+        fprintf(stderr, "DBG> %s: %s\n", header, rb_id2name(id));
+        fflush(stderr);
     }
     return id;
 }
@@ -151,8 +153,8 @@ NODE *
 ruby_debug_print_node(int level, int debug_level, const char *header, const NODE *node)
 {
     if (level < debug_level) {
-	fprintf(stderr, "DBG> %s: %s (%u)\n", header,
-		ruby_node_name(nd_type(node)), nd_line(node));
+        fprintf(stderr, "DBG> %s: %s (%u)\n", header,
+                ruby_node_name(nd_type(node)), nd_line(node));
     }
     return (NODE *)node;
 }
@@ -182,11 +184,11 @@ ruby_env_debug_option(const char *str, int len, void *arg)
     size_t retlen;
     unsigned long n;
 #define SET_WHEN(name, var, val) do {	    \
-	if (len == sizeof(name) - 1 &&	    \
-	    strncmp(str, (name), len) == 0) { \
-	    (var) = (val);		    \
-	    return 1;			    \
-	}				    \
+        if (len == sizeof(name) - 1 &&	    \
+            strncmp(str, (name), len) == 0) { \
+            (var) = (val);		    \
+            return 1;			    \
+        }				    \
     } while (0)
 #define NAME_MATCH_VALUE(name)				\
     ((size_t)len >= sizeof(name)-1 &&			\
@@ -195,24 +197,24 @@ ruby_env_debug_option(const char *str, int len, void *arg)
       (str[sizeof(name)-1] == '=' &&			\
        (str += sizeof(name), len -= sizeof(name), 1))))
 #define SET_UINT(val) do { \
-	n = ruby_scan_digits(str, len, 10, &retlen, &ov); \
-	if (!ov && retlen) { \
-	    val = (unsigned int)n; \
-	} \
-	str += retlen; \
-	len -= retlen; \
+        n = ruby_scan_digits(str, len, 10, &retlen, &ov); \
+        if (!ov && retlen) { \
+            val = (unsigned int)n; \
+        } \
+        str += retlen; \
+        len -= retlen; \
     } while (0)
 #define SET_UINT_LIST(name, vals, num) do { \
-	int i; \
-	for (i = 0; i < (num); ++i) { \
-	    SET_UINT((vals)[i]); \
-	    if (!len || *str != ':') break; \
-	    ++str; \
-	    --len; \
-	} \
-	if (len > 0) { \
-	    fprintf(stderr, "ignored "name" option: `%.*s'\n", len, str); \
-	} \
+        int i; \
+        for (i = 0; i < (num); ++i) { \
+            SET_UINT((vals)[i]); \
+            if (!len || *str != ':') break; \
+            ++str; \
+            --len; \
+        } \
+        if (len > 0) { \
+            fprintf(stderr, "ignored "name" option: `%.*s'\n", len, str); \
+        } \
     } while (0)
 #define SET_WHEN_UINT(name, vals, num, req) \
     if (NAME_MATCH_VALUE(name)) SET_UINT_LIST(name, vals, num);
@@ -221,9 +223,9 @@ ruby_env_debug_option(const char *str, int len, void *arg)
     SET_WHEN("core", ruby_enable_coredump, 1);
     SET_WHEN("ci", ruby_on_ci, 1);
     if (NAME_MATCH_VALUE("rgengc")) {
-	if (!len) ruby_rgengc_debug = 1;
-	else SET_UINT_LIST("rgengc", &ruby_rgengc_debug, 1);
-	return 1;
+        if (!len) ruby_rgengc_debug = 1;
+        else SET_UINT_LIST("rgengc", &ruby_rgengc_debug, 1);
+        return 1;
     }
 #if defined _WIN32
 # if RUBY_MSVCRT_VERSION >= 80
@@ -232,9 +234,9 @@ ruby_env_debug_option(const char *str, int len, void *arg)
 #endif
 #if defined _WIN32 || defined __CYGWIN__
     if (NAME_MATCH_VALUE("codepage")) {
-	if (!len) fprintf(stderr, "missing codepage argument");
-	else SET_UINT_LIST("codepage", ruby_w32_codepage, numberof(ruby_w32_codepage));
-	return 1;
+        if (!len) fprintf(stderr, "missing codepage argument");
+        else SET_UINT_LIST("codepage", ruby_w32_codepage, numberof(ruby_w32_codepage));
+        return 1;
     }
 #endif
     return 0;
@@ -244,7 +246,7 @@ static void
 set_debug_option(const char *str, int len, void *arg)
 {
     if (!ruby_env_debug_option(str, len, arg)) {
-	fprintf(stderr, "unexpected debug option: %.*s\n", len, str);
+        fprintf(stderr, "unexpected debug option: %.*s\n", len, str);
     }
 }
 
@@ -268,14 +270,31 @@ ruby_set_debug_option(const char *str)
 
 #define MAX_DEBUG_LOG             0x1000
 #define MAX_DEBUG_LOG_MESSAGE_LEN 0x0200
-#define MAX_DEBUG_LOG_FILTER      0x0010
+#define MAX_DEBUG_LOG_FILTER_LEN  0x0020
+#define MAX_DEBUG_LOG_FILTER_NUM  0x0010
 
 enum ruby_debug_log_mode ruby_debug_log_mode;
 
+struct debug_log_filter {
+    enum debug_log_filter_type {
+        dlf_all,
+        dlf_file, // "file:..."
+        dlf_func, // "func:..."
+    } type;
+    bool negative;
+    char str[MAX_DEBUG_LOG_FILTER_LEN];
+};
+
+static const char *dlf_type_names[] = {
+    "all",
+    "file",
+    "func",
+};
+
 static struct {
     char *mem;
     unsigned int cnt;
-    char filters[MAX_DEBUG_LOG_FILTER][MAX_DEBUG_LOG_FILTER];
+    struct debug_log_filter filters[MAX_DEBUG_LOG_FILTER_NUM];
     unsigned int filters_num;
     rb_nativethread_lock_t lock;
     FILE *output;
@@ -287,15 +306,86 @@ RUBY_DEBUG_LOG_MEM_ENTRY(unsigned int index)
     return &debug_log.mem[MAX_DEBUG_LOG_MESSAGE_LEN * index];
 }
 
+static enum debug_log_filter_type
+filter_type(const char *str, int *skiplen)
+{
+    if (strncmp(str, "file:", 5) == 0) {
+        *skiplen = 5;
+        return dlf_file;
+    }
+    else if(strncmp(str, "func:", 5) == 0) {
+        *skiplen = 5;
+        return dlf_func;
+    }
+    else {
+        *skiplen = 0;
+        return dlf_all;
+    }
+}
+
+static void
+setup_debug_log_filter(void)
+{
+    const char *filter_config = getenv("RUBY_DEBUG_LOG_FILTER");
+
+    if (filter_config && strlen(filter_config) > 0) {
+        unsigned int i;
+        for (i=0; i<MAX_DEBUG_LOG_FILTER_NUM && filter_config; i++) {
+            size_t len;
+            const char *str = filter_config;
+            const char *p;
+
+            if ((p = strchr(str, ',')) == NULL) {
+                len = strlen(str);
+                filter_config = NULL;
+            }
+            else {
+                len = p - str - 1; // 1 is ','
+                filter_config = p + 1;
+            }
+
+            // positive/negative
+            if (*str == '-') {
+                debug_log.filters[i].negative = true;
+                str++;
+            }
+            else if (*str == '+') {
+                // negative is false on default.
+                str++;
+            }
+
+            // type
+            int skiplen;
+            debug_log.filters[i].type = filter_type(str, &skiplen);
+            len -= skiplen;
+
+            if (len >= MAX_DEBUG_LOG_FILTER_LEN) {
+                fprintf(stderr, "too long: %s (max:%d)\n", str, MAX_DEBUG_LOG_FILTER_LEN - 1);
+                exit(1);
+            }
+
+            // body
+            strncpy(debug_log.filters[i].str, str + skiplen, len);
+            debug_log.filters[i].str[len] = 0;
+        }
+        debug_log.filters_num = i;
+
+        for (i=0; i<debug_log.filters_num; i++) {
+            fprintf(stderr, "RUBY_DEBUG_LOG_FILTER[%d]=%s (%s%s)\n", i,
+                    debug_log.filters[i].str,
+                    debug_log.filters[i].negative ? "-" : "",
+                    dlf_type_names[debug_log.filters[i].type]);
+        }
+    }
+}
+
 static void
 setup_debug_log(void)
 {
     // check RUBY_DEBUG_LOG
     const char *log_config = getenv("RUBY_DEBUG_LOG");
-    if (log_config) {
-        fprintf(stderr, "RUBY_DEBUG_LOG=%s\n", log_config);
-
-        if  (strcmp(log_config, "mem") == 0) {
+    if (log_config && strlen(log_config) > 0) {
+        if (strcmp(log_config, "mem") == 0) {
             debug_log.mem = (char *)malloc(MAX_DEBUG_LOG * MAX_DEBUG_LOG_MESSAGE_LEN);
             if (debug_log.mem == NULL) {
                 fprintf(stderr, "setup_debug_log failed (can't allocate memory)\n");
@@ -315,51 +405,83 @@ setup_debug_log(void)
             setvbuf(debug_log.output, NULL, _IONBF, 0);
         }
 
+        fprintf(stderr, "RUBY_DEBUG_LOG=%s %s%s%s\n", log_config,
+                (ruby_debug_log_mode & ruby_debug_log_memory) ? "[mem]" : "",
+                (ruby_debug_log_mode & ruby_debug_log_stderr) ? "[stderr]" : "",
+                (ruby_debug_log_mode & ruby_debug_log_file)   ? "[file]" : "");
         rb_nativethread_lock_initialize(&debug_log.lock);
+
+        setup_debug_log_filter();
     }
+}
 
-    // check RUBY_DEBUG_LOG_FILTER
-    const char *filter_config = getenv("RUBY_DEBUG_LOG_FILTER");
-    if (filter_config && strlen(filter_config) > 0) {
-        unsigned int i;
-        for (i=0; i<MAX_DEBUG_LOG_FILTER; i++) {
-            const char *p;
-            if ((p = strchr(filter_config, ',')) == NULL) {
-                if (strlen(filter_config) >= MAX_DEBUG_LOG_FILTER) {
-                    fprintf(stderr, "too long: %s (max:%d)\n", filter_config, MAX_DEBUG_LOG_FILTER);
-                    exit(1);
-                }
-                strncpy(debug_log.filters[i], filter_config, MAX_DEBUG_LOG_FILTER - 1);
-                i++;
-                break;
-            }
-            else {
-                size_t n = p - filter_config;
-                if (n >= MAX_DEBUG_LOG_FILTER) {
-                    fprintf(stderr, "too long: %s (max:%d)\n", filter_config, MAX_DEBUG_LOG_FILTER);
-                    exit(1);
-                }
-                strncpy(debug_log.filters[i], filter_config, n);
-                filter_config = p+1;
-            }
+static bool
+check_filter(const char *str, const struct debug_log_filter *filter, bool *state)
+{
+    if (filter->negative) {
+        if (strstr(str, filter->str) == NULL) {
+            *state = true;
+            return false;
         }
-        debug_log.filters_num = i;
-        for (i=0; i<debug_log.filters_num; i++) {
-            fprintf(stderr, "RUBY_DEBUG_LOG_FILTER[%d]=%s\n", i, debug_log.filters[i]);
+        else {
+            *state = false;
+            return true;
+        }
+    }
+    else {
+        if (strstr(str, filter->str) != NULL) {
+            *state = true;
+            return true;
+        }
+        else {
+            *state = false;
+            return false;
         }
     }
 }
 
+//
+// RUBY_DEBUG_LOG_FILTER=-foo,-bar,baz,boo
+// returns true if
+//   (func_name or file_name) doesn't contain foo
+// and
+//   (func_name or file_name) doesn't contain bar
+// and
+//   (func_name or file_name) contains baz or boo
+//
+// RUBY_DEBUG_LOG_FILTER=foo,bar,-baz,-boo
+// retunrs true if
+//   (func_name or file_name) contains foo or bar
+// or
+//   (func_name or file_name) doesn't contain baz and
+//   (func_name or file_name) doesn't contain boo and
+//
+// You can specify "file:" (ex file:foo) or "func:" (ex  func:foo)
+// prefixes to specify the filter for.
+//
 bool
-ruby_debug_log_filter(const char *func_name)
+ruby_debug_log_filter(const char *func_name, const char *file_name)
 {
     if (debug_log.filters_num > 0) {
+        bool state = false;
+
         for (unsigned int i = 0; i<debug_log.filters_num; i++) {
-            if (strstr(func_name, debug_log.filters[i]) != NULL) {
-                return true;
+            const struct debug_log_filter *filter = &debug_log.filters[i];
+
+            switch (filter->type) {
+              case dlf_all:
+                if (check_filter(func_name, filter, &state)) return state;
+                if (check_filter(file_name, filter, &state)) return state;
+                break;
+              case dlf_func:
+                if (check_filter(func_name, filter, &state)) return state;
+                break;
+              case dlf_file:
+                if (check_filter(file_name, filter, &state)) return state;
+                break;
             }
         }
-        return false;
+        return state;
     }
     else {
         return true;
@@ -377,6 +499,7 @@ pretty_filename(const char *path)
     return path;
 }
 
+#undef ruby_debug_log
 void
 ruby_debug_log(const char *file, int line, const char *func_name, const char *fmt, ...)
 {
@@ -410,36 +533,36 @@ ruby_debug_log(const char *file, int line, const char *func_name, const char *fm
         len += r;
     }
 
-    // Ruby location
-    int ruby_line;
-    const char *ruby_file = rb_source_location_cstr(&ruby_line);
-    if (len < MAX_DEBUG_LOG_MESSAGE_LEN) {
-        if (ruby_file) {
-            r = snprintf(buff + len, MAX_DEBUG_LOG_MESSAGE_LEN - len, "\t%s:%d", pretty_filename(ruby_file), ruby_line);
-        }
-        else {
-            r = snprintf(buff + len, MAX_DEBUG_LOG_MESSAGE_LEN - len, "\t");
-        }
-        if (r < 0) rb_bug("ruby_debug_log returns %d\n", r);
-        len += r;
-    }
-
-    // ractor information
-    if (ruby_single_main_ractor == NULL) {
-        rb_ractor_t *cr = GET_RACTOR();
-        if (r && len < MAX_DEBUG_LOG_MESSAGE_LEN) {
-            r = snprintf(buff + len, MAX_DEBUG_LOG_MESSAGE_LEN - len, "\tr:#%u/%u",
-                         (unsigned int)rb_ractor_id(cr), GET_VM()->ractor.cnt);
+    if (rb_current_execution_context(false)) {
+        // Ruby location
+        int ruby_line;
+        const char *ruby_file = rb_source_location_cstr(&ruby_line);
+        if (len < MAX_DEBUG_LOG_MESSAGE_LEN) {
+            if (ruby_file) {
+                r = snprintf(buff + len, MAX_DEBUG_LOG_MESSAGE_LEN - len, "\t%s:%d", pretty_filename(ruby_file), ruby_line);
+            }
+            else {
+                r = snprintf(buff + len, MAX_DEBUG_LOG_MESSAGE_LEN - len, "\t");
+            }
             if (r < 0) rb_bug("ruby_debug_log returns %d\n", r);
             len += r;
         }
-    }
 
-    // thread information
-    if (!rb_thread_alone()) {
+        // ractor information
+        if (ruby_single_main_ractor == NULL) {
+            rb_ractor_t *cr = GET_RACTOR();
+            if (r && len < MAX_DEBUG_LOG_MESSAGE_LEN) {
+                r = snprintf(buff + len, MAX_DEBUG_LOG_MESSAGE_LEN - len, "\tr:#%u/%u",
+                             (unsigned int)rb_ractor_id(cr), GET_VM()->ractor.cnt);
+                if (r < 0) rb_bug("ruby_debug_log returns %d\n", r);
+                len += r;
+            }
+        }
+
+        // thread information
         const rb_thread_t *th = GET_THREAD();
         if (r && len < MAX_DEBUG_LOG_MESSAGE_LEN) {
-            r = snprintf(buff + len, MAX_DEBUG_LOG_MESSAGE_LEN - len, "\tth:%p", (void *)th);
+            r = snprintf(buff + len, MAX_DEBUG_LOG_MESSAGE_LEN - len, "\tth:%u", rb_th_serial(th));
             if (r < 0) rb_bug("ruby_debug_log returns %d\n", r);
             len += r;
         }
diff --git a/debug_counter.c b/debug_counter.c
index e7b0bb0acd..463bebf849 100644
--- a/debug_counter.c
+++ b/debug_counter.c
@@ -16,19 +16,21 @@
 
 #if USE_DEBUG_COUNTER
 
-static const char *const debug_counter_names[] = {
-    ""
+const char *const rb_debug_counter_names[] = {
+#define DEBUG_COUNTER_NAME_EMPTY "" /* Suppress -Wstring-concatenation */
+    DEBUG_COUNTER_NAME_EMPTY
+#undef DEBUG_COUNTER_NAME_EMPTY
 #define RB_DEBUG_COUNTER(name) #name,
 #include "debug_counter.h"
 #undef RB_DEBUG_COUNTER
 };
 
 MJIT_SYMBOL_EXPORT_BEGIN
-size_t rb_debug_counter[numberof(debug_counter_names)];
+size_t rb_debug_counter[numberof(rb_debug_counter_names)];
 void rb_debug_counter_add_atomic(enum rb_debug_counter_type type, int add);
 MJIT_SYMBOL_EXPORT_END
 
-rb_nativethread_lock_t debug_counter_lock;
+static rb_nativethread_lock_t debug_counter_lock;
 
 __attribute__((constructor))
 static void
@@ -47,24 +49,14 @@ rb_debug_counter_add_atomic(enum rb_debug_counter_type type, int add)
     rb_nativethread_lock_unlock(&debug_counter_lock);
 }
 
-int debug_counter_disable_show_at_exit = 0;
+static int debug_counter_disable_show_at_exit = 0;
 
 // note that this operation is not atomic.
 void
 ruby_debug_counter_reset(void)
 {
     for (int i = 0; i < RB_DEBUG_COUNTER_MAX; i++) {
-        switch (i) {
-          case RB_DEBUG_COUNTER_mjit_length_unit_queue:
-          case RB_DEBUG_COUNTER_mjit_length_active_units:
-          case RB_DEBUG_COUNTER_mjit_length_compact_units:
-          case RB_DEBUG_COUNTER_mjit_length_stale_units:
-            // These counters may be decreased and should not be reset.
-            break;
-          default:
-            rb_debug_counter[i] = 0;
-            break;
-        }
+        rb_debug_counter[i] = 0;
     }
 }
 
@@ -75,7 +67,7 @@ ruby_debug_counter_get(const char **names_ptr, size_t *counters_ptr)
     int i;
     if (names_ptr != NULL) {
         for (i=0; i<RB_DEBUG_COUNTER_MAX; i++) {
-            names_ptr[i] = debug_counter_names[i];
+            names_ptr[i] = rb_debug_counter_names[i];
         }
     }
     if (counters_ptr != NULL) {
@@ -101,13 +93,13 @@ rb_debug_counter_show_results(const char *msg)
     setlocale(LC_NUMERIC, "");
 
     if (env == NULL || strcmp("1", env) != 0) {
-	int i;
+        int i;
         fprintf(stderr, "[RUBY_DEBUG_COUNTER]\t%d %s\n", getpid(), msg);
-	for (i=0; i<RB_DEBUG_COUNTER_MAX; i++) {
+        for (i=0; i<RB_DEBUG_COUNTER_MAX; i++) {
             fprintf(stderr, "[RUBY_DEBUG_COUNTER]\t%-30s\t%'14"PRIuSIZE"\n",
-		    debug_counter_names[i],
-		    rb_debug_counter[i]);
-	}
+                    rb_debug_counter_names[i],
+                    rb_debug_counter[i]);
+        }
     }
 }
 
diff --git a/debug_counter.h b/debug_counter.h
index 3f0dec948f..6e0b8dee60 100644
--- a/debug_counter.h
+++ b/debug_counter.h
@@ -130,7 +130,6 @@ RB_DEBUG_COUNTER(frame_C2R)
 /* instance variable counts
  *
  * * ivar_get_ic_hit/miss: ivar_get inline cache (ic) hit/miss counts (VM insn)
- * * ivar_get_ic_miss_serial: ivar_get ic miss reason by serial (VM insn)
  * * ivar_get_ic_miss_unset:                      ... by unset (VM insn)
  * * ivar_get_ic_miss_noobject:                   ... by "not T_OBJECT" (VM insn)
  * * ivar_set_...: same counts with ivar_set (VM insn)
@@ -140,17 +139,17 @@ RB_DEBUG_COUNTER(frame_C2R)
  */
 RB_DEBUG_COUNTER(ivar_get_ic_hit)
 RB_DEBUG_COUNTER(ivar_get_ic_miss)
-RB_DEBUG_COUNTER(ivar_get_ic_miss_serial)
-RB_DEBUG_COUNTER(ivar_get_ic_miss_unset)
 RB_DEBUG_COUNTER(ivar_get_ic_miss_noobject)
 RB_DEBUG_COUNTER(ivar_set_ic_hit)
 RB_DEBUG_COUNTER(ivar_set_ic_miss)
-RB_DEBUG_COUNTER(ivar_set_ic_miss_serial)
-RB_DEBUG_COUNTER(ivar_set_ic_miss_unset)
 RB_DEBUG_COUNTER(ivar_set_ic_miss_iv_hit)
 RB_DEBUG_COUNTER(ivar_set_ic_miss_noobject)
 RB_DEBUG_COUNTER(ivar_get_base)
 RB_DEBUG_COUNTER(ivar_set_base)
+RB_DEBUG_COUNTER(ivar_get_ic_miss_set)
+RB_DEBUG_COUNTER(ivar_get_cc_miss_set)
+RB_DEBUG_COUNTER(ivar_get_ic_miss_unset)
+RB_DEBUG_COUNTER(ivar_get_cc_miss_unset)
 
 /* local variable counts
  *
@@ -244,6 +243,7 @@ RB_DEBUG_COUNTER(obj_wb_unprotect)
 RB_DEBUG_COUNTER(obj_obj_embed)
 RB_DEBUG_COUNTER(obj_obj_transient)
 RB_DEBUG_COUNTER(obj_obj_ptr)
+RB_DEBUG_COUNTER(obj_obj_too_complex)
 
 RB_DEBUG_COUNTER(obj_str_ptr)
 RB_DEBUG_COUNTER(obj_str_embed)
@@ -347,41 +347,6 @@ RB_DEBUG_COUNTER(vm_sync_lock_enter_nb)
 RB_DEBUG_COUNTER(vm_sync_lock_enter_cr)
 RB_DEBUG_COUNTER(vm_sync_barrier)
 
-/* mjit_exec() counts */
-RB_DEBUG_COUNTER(mjit_exec)
-RB_DEBUG_COUNTER(mjit_exec_not_added)
-RB_DEBUG_COUNTER(mjit_exec_not_ready)
-RB_DEBUG_COUNTER(mjit_exec_not_compiled)
-RB_DEBUG_COUNTER(mjit_exec_call_func)
-
-/* MJIT enqueue / unload */
-RB_DEBUG_COUNTER(mjit_add_iseq_to_process)
-RB_DEBUG_COUNTER(mjit_unload_units)
-
-/* MJIT <-> VM frame push counts */
-RB_DEBUG_COUNTER(mjit_frame_VM2VM)
-RB_DEBUG_COUNTER(mjit_frame_VM2JT)
-RB_DEBUG_COUNTER(mjit_frame_JT2JT)
-RB_DEBUG_COUNTER(mjit_frame_JT2VM)
-
-/* MJIT cancel counters */
-RB_DEBUG_COUNTER(mjit_cancel)
-RB_DEBUG_COUNTER(mjit_cancel_ivar_inline)
-RB_DEBUG_COUNTER(mjit_cancel_exivar_inline)
-RB_DEBUG_COUNTER(mjit_cancel_send_inline)
-RB_DEBUG_COUNTER(mjit_cancel_opt_insn) /* CALL_SIMPLE_METHOD */
-RB_DEBUG_COUNTER(mjit_cancel_invalidate_all)
-RB_DEBUG_COUNTER(mjit_cancel_leave)
-
-/* rb_mjit_unit_list length */
-RB_DEBUG_COUNTER(mjit_length_unit_queue)
-RB_DEBUG_COUNTER(mjit_length_active_units)
-RB_DEBUG_COUNTER(mjit_length_compact_units)
-RB_DEBUG_COUNTER(mjit_length_stale_units)
-
-/* Other MJIT counters */
-RB_DEBUG_COUNTER(mjit_compile_failures)
-
 /* load (not implemented yet) */
 /*
 RB_DEBUG_COUNTER(load_files)
diff --git a/defs/gmake.mk b/defs/gmake.mk
index 27e3e21cc4..54fef6685f 100644
--- a/defs/gmake.mk
+++ b/defs/gmake.mk
@@ -11,11 +11,15 @@ override ACTIONS_GROUP = @echo "\#\#[group]$(patsubst yes-%,%,$@)"
 override ACTIONS_ENDGROUP = @echo "\#\#[endgroup]"
 endif
 
-ifneq ($(filter %darwin%,$(arch)),)
-INSTRUBY_ENV += SDKROOT=/
+ifneq ($(filter darwin%,$(target_os)),)
+# Remove debug option not to generate thousands of .dSYM
+MJIT_DEBUGFLAGS := $(filter-out -g%,$(MJIT_DEBUGFLAGS))
+
+INSTRUBY_ENV += SDKROOT=
 endif
 INSTRUBY_ARGS += --gnumake
 
+ifeq ($(DOT_WAIT),)
 CHECK_TARGETS := great exam love check test check% test% btest%
 # expand test targets, and those dependents
 TEST_TARGETS := $(filter $(CHECK_TARGETS),$(MAKECMDGOALS))
@@ -23,7 +27,7 @@ TEST_DEPENDS := $(filter-out commit $(TEST_TARGETS),$(MAKECMDGOALS))
 TEST_TARGETS := $(patsubst great,exam,$(TEST_TARGETS))
 TEST_DEPENDS := $(filter-out great $(TEST_TARGETS),$(TEST_DEPENDS))
 TEST_TARGETS := $(patsubst exam,check,$(TEST_TARGETS))
-TEST_TARGETS := $(patsubst check,test-spec test-all test-tool test-short,$(TEST_TARGETS))
+TEST_TARGETS := $(patsubst check,test-syntax-suggest test-spec test-all test-tool test-short,$(TEST_TARGETS))
 TEST_TARGETS := $(patsubst test-rubyspec,test-spec,$(TEST_TARGETS))
 TEST_DEPENDS := $(filter-out exam check test-spec $(TEST_TARGETS),$(TEST_DEPENDS))
 TEST_TARGETS := $(patsubst love,check,$(TEST_TARGETS))
@@ -36,15 +40,13 @@ TEST_TARGETS := $(patsubst test-short,btest-ruby test-knownbug test-basic,$(TEST
 TEST_TARGETS := $(patsubst test-bundled-gems,test-bundled-gems-run,$(TEST_TARGETS))
 TEST_TARGETS := $(patsubst test-bundled-gems-run,test-bundled-gems-run $(PREPARE_BUNDLED_GEMS),$(TEST_TARGETS))
 TEST_TARGETS := $(patsubst test-bundled-gems-prepare,test-bundled-gems-prepare $(PRECHECK_BUNDLED_GEMS) test-bundled-gems-fetch,$(TEST_TARGETS))
+TEST_TARGETS := $(patsubst test-syntax-suggest,test-syntax-suggest $(PREPARE_SYNTAX_SUGGEST),$(TEST_TARGETS))
 TEST_DEPENDS := $(filter-out test-short $(TEST_TARGETS),$(TEST_DEPENDS))
 TEST_DEPENDS += $(if $(filter great exam love check,$(MAKECMDGOALS)),all exts)
+endif
 
 in-srcdir := $(if $(filter-out .,$(srcdir)),$(CHDIR) $(srcdir) &&)
 
-ifneq ($(filter -O0 -Od,$(optflags)),)
-override XCFLAGS := $(filter-out -D_FORTIFY_SOURCE=%,$(XCFLAGS))
-endif
-
 ifeq ($(if $(filter all main exts enc trans libencs libenc libtrans \
 		    prog program ruby ruby$(EXEEXT) \
 		    wprogram rubyw rubyw$(EXEEXT) \
@@ -72,6 +74,7 @@ $(foreach arch,$(arch_flags),\
 	$(eval $(call archcmd,$(patsubst -arch=%,%,$(value arch)),$(patsubst -arch=%,-arch %,$(value arch)))))
 endif
 
+ifeq ($(DOT_WAIT),)
 .PHONY: $(addprefix yes-,$(TEST_TARGETS))
 
 ifneq ($(filter-out btest%,$(TEST_TARGETS)),)
@@ -81,7 +84,8 @@ endif
 ORDERED_TEST_TARGETS := $(filter $(TEST_TARGETS), \
 	btest-ruby test-knownbug test-basic \
 	test-testframework test-tool test-ruby test-all \
-	test-spec test-bundler-prepare test-bundler test-bundler-parallel \
+	test-spec test-syntax-suggest-prepare test-syntax-suggest \
+	test-bundler-prepare test-bundler test-bundler-parallel \
 	test-bundled-gems-precheck test-bundled-gems-fetch \
 	test-bundled-gems-prepare test-bundled-gems-run \
 	)
@@ -89,6 +93,7 @@ prev_test := $(if $(filter test-spec,$(ORDERED_TEST_TARGETS)),test-spec-precheck
 $(foreach test,$(ORDERED_TEST_TARGETS), \
 	$(eval yes-$(value test) no-$(value test): $(value prev_test)); \
 	$(eval prev_test := $(value test)))
+endif
 
 ifneq ($(if $(filter install,$(MAKECMDGOALS)),$(filter uninstall,$(MAKECMDGOALS))),)
 install-targets := $(filter install uninstall,$(MAKECMDGOALS))
@@ -134,7 +139,7 @@ config.status: $(wildcard config.cache)
 STUBPROGRAM = rubystub$(EXEEXT)
 IGNOREDPATTERNS = %~ .% %.orig %.rej \#%\#
 SCRIPTBINDIR := $(if $(EXEEXT),,exec/)
-SCRIPTPROGRAMS = $(addprefix $(SCRIPTBINDIR),$(addsuffix $(EXEEXT),$(filter-out $(IGNOREDPATTERNS),$(notdir $(wildcard $(srcdir)/libexec/*)))))
+SCRIPTPROGRAMS = $(addprefix $(SCRIPTBINDIR),$(addsuffix $(EXEEXT),$(filter-out $(IGNOREDPATTERNS),$(notdir $(wildcard $(srcdir)/bin/*)))))
 
 stub: $(STUBPROGRAM)
 scriptbin: $(SCRIPTPROGRAMS)
@@ -160,9 +165,8 @@ $(SCRIPTBINDIR)%$(EXEEXT): bin/% $(STUBPROGRAM) \
 	$(Q) chmod +x $@
 	$(Q) $(POSTLINK)
 
-$(TIMESTAMPDIR)/.exec.time:
-	$(Q) mkdir exec
-	$(Q) exit > $@
+$(SCRIPTBINDIR):
+	$(Q) mkdir $@
 
 .PHONY: commit
 commit: $(if $(filter commit,$(MAKECMDGOALS)),$(filter-out commit,$(MAKECMDGOALS))) up
@@ -180,8 +184,8 @@ commit: $(if $(filter commit,$(MAKECMDGOALS)),$(filter-out commit,$(MAKECMDGOALS
 GITHUB_RUBY_URL = https://github.com/ruby/ruby
 PR =
 
-COMMIT_GPG_SIGN = $(shell git -C "$(srcdir)" config commit.gpgsign)
-REMOTE_GITHUB_URL = $(shell git -C "$(srcdir)" config remote.github.url)
+COMMIT_GPG_SIGN = $(shell $(GIT) -C "$(srcdir)" config commit.gpgsign)
+REMOTE_GITHUB_URL = $(shell $(GIT) -C "$(srcdir)" config remote.github.url)
 COMMITS_NOTES = commits
 
 .PHONY: fetch-github
@@ -194,21 +198,21 @@ define fetch-github
 	  exit 1; \
 	)
 	$(eval REMOTE_GITHUB_URL := $(REMOTE_GITHUB_URL))
-	$(if $(REMOTE_GITHUB_URL),, \
-	  echo adding $(GITHUB_RUBY_URL) as remote github; \
-	  git -C "$(srcdir)" remote add github $(GITHUB_RUBY_URL); \
-	  git -C "$(srcdir)" config --add remote.github.fetch +refs/notes/$(COMMITS_NOTES):refs/notes/$(COMMITS_NOTES)
-	  $(eval REMOTE_GITHUB_URL := $(GITHUB_RUBY_URL)) \
+	$(if $(REMOTE_GITHUB_URL),,
+	  echo adding $(GITHUB_RUBY_URL) as remote github
+	  $(GIT) -C "$(srcdir)" remote add github $(GITHUB_RUBY_URL)
+	  $(GIT) -C "$(srcdir)" config --add remote.github.fetch +refs/notes/$(COMMITS_NOTES):refs/notes/$(COMMITS_NOTES)
+	  $(eval REMOTE_GITHUB_URL := $(GITHUB_RUBY_URL))
 	)
-	$(if $(git -C "$(srcdir)" rev-parse "github/pull/$(1)/head" -- 2> /dev/null), \
-	    git -C "$(srcdir)" branch -f "gh-$(1)" "github/pull/$(1)/head", \
-	    git -C "$(srcdir)" fetch -f github "pull/$(1)/head:gh-$(1)" \
+	$(if $(shell $(GIT) -C "$(srcdir)" rev-parse "github/pull/$(1)/head" -- 2> /dev/null),
+	    $(GIT) -C "$(srcdir)" branch -f "gh-$(1)" "github/pull/$(1)/head",
+	    $(GIT) -C "$(srcdir)" fetch -f github "pull/$(1)/head:gh-$(1)"
 	)
 endef
 
 .PHONY: checkout-github
 checkout-github: fetch-github
-	git -C "$(srcdir)" checkout "gh-$(PR)"
+	$(GIT) -C "$(srcdir)" checkout "gh-$(PR)"
 
 .PHONY: update-github
 update-github: fetch-github
@@ -221,31 +225,31 @@ update-github: fetch-github
 	$(eval PR_BRANCH := $(word 2,$(PULL_REQUEST_FORK_BRANCH)))
 
 	$(eval GITHUB_UPDATE_WORKTREE := $(shell mktemp -d "$(srcdir)/gh-$(PR)-XXXXXX"))
-	git -C "$(srcdir)" worktree add $(notdir $(GITHUB_UPDATE_WORKTREE)) "gh-$(PR)"
-	git -C "$(GITHUB_UPDATE_WORKTREE)" merge master --no-edit
+	$(GIT) -C "$(srcdir)" worktree add $(notdir $(GITHUB_UPDATE_WORKTREE)) "gh-$(PR)"
+	$(GIT) -C "$(GITHUB_UPDATE_WORKTREE)" merge master --no-edit
 	@$(BASERUBY) -e 'print "Are you sure to push this to PR=$(PR)? [Y/n]: "; exit(gets.chomp != "n")'
-	git -C "$(srcdir)" remote add fork-$(PR) git@github.com:$(FORK_REPO).git
-	git -C "$(GITHUB_UPDATE_WORKTREE)" push fork-$(PR) gh-$(PR):$(PR_BRANCH)
-	git -C "$(srcdir)" remote rm fork-$(PR)
-	git -C "$(srcdir)" worktree remove $(notdir $(GITHUB_UPDATE_WORKTREE))
-	git -C "$(srcdir)" branch -D gh-$(PR)
+	$(GIT) -C "$(srcdir)" remote add fork-$(PR) git@github.com:$(FORK_REPO).git
+	$(GIT) -C "$(GITHUB_UPDATE_WORKTREE)" push fork-$(PR) gh-$(PR):$(PR_BRANCH)
+	$(GIT) -C "$(srcdir)" remote rm fork-$(PR)
+	$(GIT) -C "$(srcdir)" worktree remove $(notdir $(GITHUB_UPDATE_WORKTREE))
+	$(GIT) -C "$(srcdir)" branch -D gh-$(PR)
 
 .PHONY: pull-github
 pull-github: fetch-github
 	$(call pull-github,$(PR))
 
 define pull-github
-	$(eval GITHUB_MERGE_BASE := $(shell git -C "$(srcdir)" log -1 --format=format:%H))
-	$(eval GITHUB_MERGE_BRANCH := $(shell git -C "$(srcdir)" symbolic-ref --short HEAD))
+	$(eval GITHUB_MERGE_BASE := $(shell $(GIT) -C "$(srcdir)" log -1 --format=format:%H))
+	$(eval GITHUB_MERGE_BRANCH := $(shell $(GIT) -C "$(srcdir)" symbolic-ref --short HEAD))
 	$(eval GITHUB_MERGE_WORKTREE := $(shell mktemp -d "$(srcdir)/gh-$(1)-XXXXXX"))
-	git -C "$(srcdir)" worktree prune
-	git -C "$(srcdir)" worktree add $(notdir $(GITHUB_MERGE_WORKTREE)) "gh-$(1)"
-	git -C "$(GITHUB_MERGE_WORKTREE)" rebase $(GITHUB_MERGE_BRANCH)
+	$(GIT) -C "$(srcdir)" worktree prune
+	$(GIT) -C "$(srcdir)" worktree add $(notdir $(GITHUB_MERGE_WORKTREE)) "gh-$(1)"
+	$(GIT) -C "$(GITHUB_MERGE_WORKTREE)" rebase $(GITHUB_MERGE_BRANCH)
 	$(eval COMMIT_GPG_SIGN := $(COMMIT_GPG_SIGN))
 	$(if $(filter true,$(COMMIT_GPG_SIGN)), \
-	  git -C "$(GITHUB_MERGE_WORKTREE)" rebase --exec "git commit --amend --no-edit -S" "$(GITHUB_MERGE_BASE)"; \
+	  $(GIT) -C "$(GITHUB_MERGE_WORKTREE)" rebase --exec "$(GIT) commit --amend --no-edit -S" "$(GITHUB_MERGE_BASE)"; \
 	)
-	git -C "$(GITHUB_MERGE_WORKTREE)" rebase --exec "git notes add --message 'Merged: $(GITHUB_RUBY_URL)/pull/$(1)'" "$(GITHUB_MERGE_BASE)"
+	$(GIT) -C "$(GITHUB_MERGE_WORKTREE)" rebase --exec "$(GIT) notes add --message 'Merged: $(GITHUB_RUBY_URL)/pull/$(1)'" "$(GITHUB_MERGE_BASE)"
 endef
 
 .PHONY: fetch-github-%
@@ -254,23 +258,46 @@ fetch-github-%:
 
 .PHONY: checkout-github-%
 checkout-github-%: fetch-github-%
-	git -C "$(srcdir)" checkout "gh-$*"
+	$(GIT) -C "$(srcdir)" checkout "gh-$*"
 
 .PHONY: pr-% pull-github-%
 pr-% pull-github-%: fetch-github-%
 	$(call pull-github,$*)
 
 HELP_EXTRA_TASKS = \
-	"  checkout-github:     checkout GitHub Pull Request [PR=1234]" \
-	"  pull-github:         rebase GitHub Pull Request to new worktree [PR=1234]" \
-	"  update-github:       merge master branch and push it to Pull Request [PR=1234]" \
+	"  checkout-github:       checkout GitHub Pull Request [PR=1234]" \
+	"  pull-github:           rebase GitHub Pull Request to new worktree [PR=1234]" \
+	"  update-github:         merge master branch and push it to Pull Request [PR=1234]" \
 	""
 
-extract-gems: $(HAVE_BASERUBY:yes=update-gems)
-
-bundled-gems := $(shell sed '/^[ 	]*\#/d;/^[ 	]*$$/d;s/[ 	][ 	]*/-/;s/[ 	].*//' $(srcdir)/gems/bundled_gems)
-
-update-gems: | $(patsubst %,gems/%.gem,$(bundled-gems))
+# 1. squeeze spaces
+# 2. strip and skip comment/empty lines
+# 3. "gem x.y.z URL xxxxxx" -> "gem|x.y.z|xxxxxx|URL"
+# 4. "gem x.y.z URL" -> "gem-x.y.z"
+bundled-gems := $(shell sed \
+	-e 's/[ 	][ 	]*/ /g' \
+	-e 's/^ //;/\#/d;s/ *$$//;/^$$/d' \
+	$(if $(filter yes,$(HAVE_GIT)), \
+	-e 's/^\(.*\) \(.*\) \(.*\) \(.*\)/\1|\2|\4|\3/' \
+	) \
+	-e 's/ /-/;s/ .*//' \
+	 $(srcdir)/gems/bundled_gems)
+
+bundled-gems-rev := $(filter-out $(subst |,,$(bundled-gems)),$(bundled-gems))
+bundled-gems := $(filter-out $(bundled-gems-rev),$(bundled-gems))
+
+# calls $(1) with name, version, revision, URL
+foreach-bundled-gems-rev = \
+    $(foreach g,$(bundled-gems-rev),$(call foreach-bundled-gems-rev-0,$(1),$(subst |, ,$(value g))))
+foreach-bundled-gems-rev-0 = \
+    $(call $(1),$(word 1,$(2)),$(word 2,$(2)),$(word 3,$(2)),$(word 4,$(2)))
+bundled-gem-gemfile = $(srcdir)/gems/$(1)-$(2).gem
+bundled-gem-srcdir = $(srcdir)/gems/src/$(1)
+bundled-gem-extracted = $(srcdir)/.bundle/gems/$(1)-$(2)
+
+update-gems: | $(patsubst %,$(srcdir)/gems/%.gem,$(bundled-gems))
+update-gems: | $(call foreach-bundled-gems-rev,bundled-gem-gemfile)
+update-gems: | $(call foreach-bundled-gems-rev,bundled-gem-srcdir)
 
 test-bundler-precheck: | $(srcdir)/.bundle/cache
 
@@ -278,7 +305,7 @@ $(srcdir)/.bundle/cache:
 	$(MAKEDIRS) $(@D) $(CACHE_DIR)
 	$(LN_S) ../.downloaded-cache $@
 
-gems/%.gem:
+$(srcdir)/gems/%.gem:
 	$(ECHO) Downloading bundled gem $*...
 	$(Q) $(BASERUBY) -C "$(srcdir)" \
 	    -I./tool -rdownloader \
@@ -289,14 +316,39 @@ gems/%.gem:
 	    -e 'File.unlink(*old) and' \
 	    -e 'FileUtils.rm_rf(old.map{'"|n|"'n.chomp(".gem")})'
 
-extract-gems: | $(patsubst %,.bundle/gems/%,$(bundled-gems))
+extract-gems: | $(patsubst %,$(srcdir)/.bundle/gems/%,$(bundled-gems))
+extract-gems: | $(call foreach-bundled-gems-rev,bundled-gem-extracted)
 
-.bundle/gems/%: gems/%.gem | .bundle/gems
+$(srcdir)/.bundle/gems/%: $(srcdir)/gems/%.gem | .bundle/gems
 	$(ECHO) Extracting bundle gem $*...
 	$(Q) $(BASERUBY) -C "$(srcdir)" \
-	    -Itool -rgem-unpack \
-	    -e 'Gem.unpack("gems/$(@F).gem", ".bundle/gems", ".bundle/specifications")'
-	$(RMALL) "$(srcdir)/$(@:.gem=)/".git*
+	    -Itool/lib -rbundled_gem \
+	    -e 'BundledGem.unpack("gems/$(@F).gem", ".bundle")'
+
+define copy-gem
+$(srcdir)/gems/src/$(1): | $(srcdir)/gems/src
+	$(ECHO) Cloning $(4)
+	$(Q) $(GIT) clone $(4) $$(@)
+
+$(srcdir)/.bundle/gems/$(1)-$(2): | $(srcdir)/gems/src/$(1) .bundle/gems
+	$(ECHO) Copying $(1)@$(3) to $$(@F)
+	$(Q) $(CHDIR) "$(srcdir)/gems/src/$(1)" && \
+	    $(GIT) fetch origin $(3) && \
+	    $(GIT) checkout --detach $(3) && \
+	:
+	$(Q) $(BASERUBY) -C "$(srcdir)" \
+	    -Itool/lib -rbundled_gem \
+	    -e 'BundledGem.copy("gems/src/$(1)/$(1).gemspec", ".bundle")'
+
+endef
+define copy-gem-0
+$(eval $(call copy-gem,$(1),$(2),$(3),$(4)))
+endef
+
+$(call foreach-bundled-gems-rev,copy-gem-0)
+
+$(srcdir)/gems/src:
+	$(MAKEDIRS) $@
 
 $(srcdir)/.bundle/gems:
 	$(MAKEDIRS) $@
@@ -333,30 +385,26 @@ $(MJIT_MIN_HEADER): $(mjit_min_headers) $(PREP)
 
 endif
 
-ifeq ($(if $(wildcard $(filter-out .,$(UNICODE_FILES) $(UNICODE_PROPERTY_FILES))),,\
-	   $(wildcard $(srcdir)/lib/unicode_normalize/tables.rb)),)
-# Needs the dependency when any Unicode data file exists, or
-# normalization tables script doesn't.  Otherwise, when the target
-# only exists, use it as-is.
-.PHONY: $(UNICODE_SRC_DATA_DIR)/.unicode-tables.time
-UNICODE_TABLES_TIMESTAMP =
-$(UNICODE_SRC_DATA_DIR)/.unicode-tables.time: \
-	$(UNICODE_FILES) $(UNICODE_PROPERTY_FILES)
-endif
+.SECONDARY: update-unicode-files
+.SECONDARY: update-unicode-auxiliary-files
+.SECONDARY: update-unicode-ucd-emoji-files
+.SECONDARY: update-unicode-emoji-files
 
-ifeq ($(wildcard $(srcdir)/revision.h),)
-REVISION_IN_HEADER := none
-REVISION_LATEST := update
+ifeq ($(HAVE_GIT),yes)
+REVISION_LATEST := $(shell $(CHDIR) $(srcdir) && $(GIT) log -1 --format=%H 2>/dev/null)
 else
-REVISION_IN_HEADER := $(shell sed -n 's/^\#define RUBY_FULL_REVISION "\(.*\)"/\1/p' $(srcdir)/revision.h 2>/dev/null)
-REVISION_LATEST := $(shell $(CHDIR) $(srcdir) && git log -1 --format=%H 2>/dev/null)
+REVISION_LATEST := update
+endif
+REVISION_IN_HEADER := $(shell sed -n 's/^\#define RUBY_FULL_REVISION "\(.*\)"/\1/p' $(wildcard $(srcdir)/revision.h revision.h) /dev/null 2>/dev/null)
+ifeq ($(REVISION_IN_HEADER),)
+REVISION_IN_HEADER := none
 endif
 ifneq ($(REVISION_IN_HEADER),$(REVISION_LATEST))
-# GNU make treat the target as unmodified when its dependents get
-# updated but it is not updated, while others may not.
-$(srcdir)/revision.h: $(REVISION_H)
+$(REVISION_H): PHONY
 endif
 
+include $(top_srcdir)/yjit/yjit.mk
+
 # Query on the generated rdoc
 #
 #   $ make rdoc:Integer#+
@@ -399,19 +447,19 @@ endif
 update-deps:
 	$(eval update_deps := $(shell date +update-deps-%Y%m%d))
 	$(eval deps_dir := $(shell mktemp -d)/$(update_deps))
-	$(eval GIT_DIR := $(shell git -C $(srcdir) rev-parse --absolute-git-dir))
-	git --git-dir=$(GIT_DIR) worktree add $(deps_dir)
+	$(eval GIT_DIR := $(shell $(GIT) -C $(srcdir) rev-parse --absolute-git-dir))
+	$(GIT) --git-dir=$(GIT_DIR) worktree add $(deps_dir)
 	cp $(tooldir)/config.guess $(tooldir)/config.sub $(deps_dir)/tool
 	[ -f config.status ] && cp config.status $(deps_dir)
 	cd $(deps_dir) && autoconf && \
 	exec ./configure -q -C --enable-load-relative --disable-install-doc --disable-rubygems 'optflags=-O0' 'debugflags=-save-temps=obj -g'
 	$(RUNRUBY) -C $(deps_dir) tool/update-deps --fix
-	git -C $(deps_dir) diff --no-ext-diff --ignore-submodules --exit-code || \
-	    git -C $(deps_dir) commit --all --message='Update dependencies'
-	git --git-dir=$(GIT_DIR) worktree remove $(deps_dir)
+	$(GIT) -C $(deps_dir) diff --no-ext-diff --ignore-submodules --exit-code || \
+	    $(GIT) -C $(deps_dir) commit --all --message='Update dependencies'
+	$(GIT) --git-dir=$(GIT_DIR) worktree remove $(deps_dir)
 	$(RMDIR) $(dir $(deps_dir))
-	git --git-dir=$(GIT_DIR) merge --no-edit --ff-only $(update_deps)
-	git --git-dir=$(GIT_DIR) branch --delete $(update_deps)
+	$(GIT) --git-dir=$(GIT_DIR) merge --no-edit --ff-only $(update_deps)
+	$(GIT) --git-dir=$(GIT_DIR) branch --delete $(update_deps)
 
 # order-only-prerequisites doesn't work for $(RUBYSPEC_CAPIEXT)
 # because the same named directory exists in the source tree.
diff --git a/defs/id.def b/defs/id.def
index 097e34e405..ebf00506ea 100644
--- a/defs/id.def
+++ b/defs/id.def
@@ -58,6 +58,7 @@ firstline, predefined = __LINE__+1, %[\
   quo
   name
   nil
+  path
 
   _                                                     UScore
 
@@ -75,6 +76,7 @@ firstline, predefined = __LINE__+1, %[\
   "/*NULL*/"                                            NULL
   empty?
   eql?
+  default
   respond_to?                                           Respond_to
   respond_to_missing?                                   Respond_to_missing
   <IFUNC>
@@ -194,13 +196,14 @@ predefined.split(/^/).each_with_index do |line, num|
   end << token
   predefined_ids[token] = name
 end
+index = 127
 token_ops.split(/^/).each do |line|
   next if /^#/ =~ line
   line.sub!(/\s+#.*/, '')
   id, op, token = line.split
   next unless id and op
   token ||= (id unless /\A\W\z/ =~ op)
-  token_op_ids << [id, op, token]
+  token_op_ids << [id, op, token, (index += 1 if token)]
 end
 {
   "LOCAL" => local_ids,
@@ -212,4 +215,5 @@ end
   :preserved => preserved_ids,
   :predefined => predefined_ids,
   :token_op => token_op_ids,
+  :last_token => index,
 }
diff --git a/defs/keywords b/defs/keywords
index fc30ec2d15..a1b1f4f60f 100644
--- a/defs/keywords
+++ b/defs/keywords
@@ -2,7 +2,7 @@
 struct kwtable {short name, id[2], state;};
 const struct kwtable *rb_reserved_word(const char *, unsigned int);
 #ifndef RIPPER
-static const struct kwtable *reserved_word(/*!ANSI{*/const char *, unsigned int/*}!ANSI*/);
+static const struct kwtable *reserved_word(register const char *str, register size_t len);
 #define rb_reserved_word(str, len) reserved_word(str, len)
 %}
 
diff --git a/defs/lex.c.src b/defs/lex.c.src
index fc30ec2d15..a1b1f4f60f 100644
--- a/defs/lex.c.src
+++ b/defs/lex.c.src
@@ -2,7 +2,7 @@
 struct kwtable {short name, id[2], state;};
 const struct kwtable *rb_reserved_word(const char *, unsigned int);
 #ifndef RIPPER
-static const struct kwtable *reserved_word(/*!ANSI{*/const char *, unsigned int/*}!ANSI*/);
+static const struct kwtable *reserved_word(register const char *str, register size_t len);
 #define rb_reserved_word(str, len) reserved_word(str, len)
 %}
 
diff --git a/dir.c b/dir.c
index a090b9f38c..3f73f83fc5 100644
--- a/dir.c
+++ b/dir.c
@@ -77,9 +77,9 @@ char *strchr(char*,char);
 #endif
 
 #define USE_NAME_ON_FS_REAL_BASENAME 1	/* platform dependent APIs to
-					 * get real basenames */
+                                         * get real basenames */
 #define USE_NAME_ON_FS_BY_FNMATCH 2	/* select the matching
-					 * basename by fnmatch */
+                                         * basename by fnmatch */
 
 #ifdef HAVE_GETATTRLIST
 # define USE_NAME_ON_FS USE_NAME_ON_FS_REAL_BASENAME
@@ -160,12 +160,12 @@ need_normalization(DIR *dirp, const char *path)
     int ret = getattrlist(path, &al, attrbuf, sizeof(attrbuf), 0);
 #   endif
     if (!ret) {
-	const fsobj_tag_t *tag = (void *)(attrbuf+1);
-	switch (*tag) {
-	  case VT_HFS:
-	  case VT_CIFS:
-	    return TRUE;
-	}
+        const fsobj_tag_t *tag = (void *)(attrbuf+1);
+        switch (*tag) {
+          case VT_HFS:
+          case VT_CIFS:
+            return TRUE;
+        }
     }
 # endif
     return FALSE;
@@ -175,9 +175,9 @@ static inline int
 has_nonascii(const char *ptr, size_t len)
 {
     while (len > 0) {
-	if (!ISASCII(*ptr)) return 1;
-	ptr++;
-	--len;
+        if (!ISASCII(*ptr)) return 1;
+        ptr++;
+        --len;
     }
     return 0;
 }
@@ -254,53 +254,53 @@ bracket(
 
     if (p >= pend) return NULL;
     if (*p == '!' || *p == '^') {
-	not = 1;
-	p++;
+        not = 1;
+        p++;
     }
 
     while (*p != ']') {
-	const char *t1 = p;
-	if (escape && *t1 == '\\')
-	    t1++;
-	if (!*t1)
-	    return NULL;
-	p = t1 + (r = rb_enc_mbclen(t1, pend, enc));
-	if (p >= pend) return NULL;
-	if (p[0] == '-' && p[1] != ']') {
-	    const char *t2 = p + 1;
-	    int r2;
-	    if (escape && *t2 == '\\')
-		t2++;
-	    if (!*t2)
-		return NULL;
-	    p = t2 + (r2 = rb_enc_mbclen(t2, pend, enc));
-	    if (ok) continue;
-	    if ((r <= (send-s) && memcmp(t1, s, r) == 0) ||
-		(r2 <= (send-s) && memcmp(t2, s, r2) == 0)) {
-		ok = 1;
-		continue;
-	    }
-	    c1 = rb_enc_codepoint(s, send, enc);
-	    if (nocase) c1 = rb_enc_toupper(c1, enc);
-	    c2 = rb_enc_codepoint(t1, pend, enc);
-	    if (nocase) c2 = rb_enc_toupper(c2, enc);
-	    if (c1 < c2) continue;
-	    c2 = rb_enc_codepoint(t2, pend, enc);
-	    if (nocase) c2 = rb_enc_toupper(c2, enc);
-	    if (c1 > c2) continue;
-	}
-	else {
-	    if (ok) continue;
-	    if (r <= (send-s) && memcmp(t1, s, r) == 0) {
-		ok = 1;
-		continue;
-	    }
-	    if (!nocase) continue;
-	    c1 = rb_enc_toupper(rb_enc_codepoint(s, send, enc), enc);
-	    c2 = rb_enc_toupper(rb_enc_codepoint(p, pend, enc), enc);
-	    if (c1 != c2) continue;
-	}
-	ok = 1;
+        const char *t1 = p;
+        if (escape && *t1 == '\\')
+            t1++;
+        if (!*t1)
+            return NULL;
+        p = t1 + (r = rb_enc_mbclen(t1, pend, enc));
+        if (p >= pend) return NULL;
+        if (p[0] == '-' && p[1] != ']') {
+            const char *t2 = p + 1;
+            int r2;
+            if (escape && *t2 == '\\')
+                t2++;
+            if (!*t2)
+                return NULL;
+            p = t2 + (r2 = rb_enc_mbclen(t2, pend, enc));
+            if (ok) continue;
+            if ((r <= (send-s) && memcmp(t1, s, r) == 0) ||
+                (r2 <= (send-s) && memcmp(t2, s, r2) == 0)) {
+                ok = 1;
+                continue;
+            }
+            c1 = rb_enc_codepoint(s, send, enc);
+            if (nocase) c1 = rb_enc_toupper(c1, enc);
+            c2 = rb_enc_codepoint(t1, pend, enc);
+            if (nocase) c2 = rb_enc_toupper(c2, enc);
+            if (c1 < c2) continue;
+            c2 = rb_enc_codepoint(t2, pend, enc);
+            if (nocase) c2 = rb_enc_toupper(c2, enc);
+            if (c1 > c2) continue;
+        }
+        else {
+            if (ok) continue;
+            if (r <= (send-s) && memcmp(t1, s, r) == 0) {
+                ok = 1;
+                continue;
+            }
+            if (!nocase) continue;
+            c1 = rb_enc_toupper(rb_enc_codepoint(s, send, enc), enc);
+            c2 = rb_enc_toupper(rb_enc_codepoint(p, pend, enc), enc);
+            if (c1 != c2) continue;
+        }
+        ok = 1;
     }
 
     return ok == not ? NULL : (char *)p + 1;
@@ -338,72 +338,72 @@ fnmatch_helper(
     int r;
 
     if (period && *s == '.' && *UNESCAPE(p) != '.') /* leading period */
-	RETURN(FNM_NOMATCH);
+        RETURN(FNM_NOMATCH);
 
     while (1) {
-	switch (*p) {
-	  case '*':
-	    do { p++; } while (*p == '*');
-	    if (ISEND(UNESCAPE(p))) {
-		p = UNESCAPE(p);
-		RETURN(0);
-	    }
-	    if (ISEND(s))
-		RETURN(FNM_NOMATCH);
-	    ptmp = p;
-	    stmp = s;
-	    continue;
-
-	  case '?':
-	    if (ISEND(s))
-		RETURN(FNM_NOMATCH);
-	    p++;
-	    Inc(s, send, enc);
-	    continue;
-
-	  case '[': {
-	    const char *t;
-	    if (ISEND(s))
-		RETURN(FNM_NOMATCH);
-	    if ((t = bracket(p + 1, pend, s, send, flags, enc)) != 0) {
-		p = t;
-		Inc(s, send, enc);
-		continue;
-	    }
-	    goto failed;
-	  }
-	}
-
-	/* ordinary */
-	p = UNESCAPE(p);
-	if (ISEND(s))
-	    RETURN(ISEND(p) ? 0 : FNM_NOMATCH);
-	if (ISEND(p))
-	    goto failed;
-	r = rb_enc_precise_mbclen(p, pend, enc);
-	if (!MBCLEN_CHARFOUND_P(r))
-	    goto failed;
-	if (r <= (send-s) && memcmp(p, s, r) == 0) {
-	    p += r;
-	    s += r;
-	    continue;
-	}
-	if (!nocase) goto failed;
-	if (rb_enc_toupper(rb_enc_codepoint(p, pend, enc), enc) !=
-	    rb_enc_toupper(rb_enc_codepoint(s, send, enc), enc))
-	    goto failed;
-	p += r;
-	Inc(s, send, enc);
-	continue;
+        switch (*p) {
+          case '*':
+            do { p++; } while (*p == '*');
+            if (ISEND(UNESCAPE(p))) {
+                p = UNESCAPE(p);
+                RETURN(0);
+            }
+            if (ISEND(s))
+                RETURN(FNM_NOMATCH);
+            ptmp = p;
+            stmp = s;
+            continue;
+
+          case '?':
+            if (ISEND(s))
+                RETURN(FNM_NOMATCH);
+            p++;
+            Inc(s, send, enc);
+            continue;
+
+          case '[': {
+            const char *t;
+            if (ISEND(s))
+                RETURN(FNM_NOMATCH);
+            if ((t = bracket(p + 1, pend, s, send, flags, enc)) != 0) {
+                p = t;
+                Inc(s, send, enc);
+                continue;
+            }
+            goto failed;
+          }
+        }
+
+        /* ordinary */
+        p = UNESCAPE(p);
+        if (ISEND(s))
+            RETURN(ISEND(p) ? 0 : FNM_NOMATCH);
+        if (ISEND(p))
+            goto failed;
+        r = rb_enc_precise_mbclen(p, pend, enc);
+        if (!MBCLEN_CHARFOUND_P(r))
+            goto failed;
+        if (r <= (send-s) && memcmp(p, s, r) == 0) {
+            p += r;
+            s += r;
+            continue;
+        }
+        if (!nocase) goto failed;
+        if (rb_enc_toupper(rb_enc_codepoint(p, pend, enc), enc) !=
+            rb_enc_toupper(rb_enc_codepoint(s, send, enc), enc))
+            goto failed;
+        p += r;
+        Inc(s, send, enc);
+        continue;
 
       failed: /* try next '*' position */
-	if (ptmp && stmp) {
-	    p = ptmp;
-	    Inc(stmp, send, enc); /* !ISEND(*stmp) */
-	    s = stmp;
-	    continue;
-	}
-	RETURN(FNM_NOMATCH);
+        if (ptmp && stmp) {
+            p = ptmp;
+            Inc(stmp, send, enc); /* !ISEND(*stmp) */
+            s = stmp;
+            continue;
+        }
+        RETURN(FNM_NOMATCH);
     }
 }
 
@@ -424,37 +424,37 @@ fnmatch(
     const char *stmp = 0;
 
     if (pathname) {
-	while (1) {
-	    if (p[0] == '*' && p[1] == '*' && p[2] == '/') {
-		do { p += 3; } while (p[0] == '*' && p[1] == '*' && p[2] == '/');
-		ptmp = p;
-		stmp = s;
-	    }
-	    if (fnmatch_helper(&p, &s, flags, enc) == 0) {
-		while (*s && *s != '/') Inc(s, send, enc);
-		if (*p && *s) {
-		    p++;
-		    s++;
-		    continue;
-		}
-		if (!*p && !*s)
-		    return 0;
-	    }
-	    /* failed : try next recursion */
-	    if (ptmp && stmp && !(period && *stmp == '.')) {
-		while (*stmp && *stmp != '/') Inc(stmp, send, enc);
-		if (*stmp) {
-		    p = ptmp;
-		    stmp++;
-		    s = stmp;
-		    continue;
-		}
-	    }
-	    return FNM_NOMATCH;
-	}
+        while (1) {
+            if (p[0] == '*' && p[1] == '*' && p[2] == '/') {
+                do { p += 3; } while (p[0] == '*' && p[1] == '*' && p[2] == '/');
+                ptmp = p;
+                stmp = s;
+            }
+            if (fnmatch_helper(&p, &s, flags, enc) == 0) {
+                while (*s && *s != '/') Inc(s, send, enc);
+                if (*p && *s) {
+                    p++;
+                    s++;
+                    continue;
+                }
+                if (!*p && !*s)
+                    return 0;
+            }
+            /* failed : try next recursion */
+            if (ptmp && stmp && !(period && *stmp == '.')) {
+                while (*stmp && *stmp != '/') Inc(stmp, send, enc);
+                if (*stmp) {
+                    p = ptmp;
+                    stmp++;
+                    s = stmp;
+                    continue;
+                }
+            }
+            return FNM_NOMATCH;
+        }
     }
     else
-	return fnmatch_helper(&p, &s, flags, enc);
+        return fnmatch_helper(&p, &s, flags, enc);
 }
 
 VALUE rb_cDir;
@@ -520,14 +520,14 @@ static DIR *
 opendir_without_gvl(const char *path)
 {
     if (vm_initialized) {
-	union { const void *in; void *out; } u;
+        union { const void *in; void *out; } u;
 
-	u.in = path;
+        u.in = path;
 
-	return rb_thread_call_without_gvl(nogvl_opendir, u.out, RUBY_UBF_IO, 0);
+        return rb_thread_call_without_gvl(nogvl_opendir, u.out, RUBY_UBF_IO, 0);
     }
     else
-	return opendir(path);
+        return opendir(path);
 }
 
 static VALUE
@@ -551,23 +551,23 @@ dir_initialize(rb_execution_context_t *ec, VALUE dir, VALUE dirname, VALUE enc)
     path = RSTRING_PTR(dirname);
     dp->dir = opendir_without_gvl(path);
     if (dp->dir == NULL) {
-	int e = errno;
-	if (rb_gc_for_fd(e)) {
-	    dp->dir = opendir_without_gvl(path);
-	}
+        int e = errno;
+        if (rb_gc_for_fd(e)) {
+            dp->dir = opendir_without_gvl(path);
+        }
 #ifdef HAVE_GETATTRLIST
-	else if (e == EIO) {
-	    u_int32_t attrbuf[1];
-	    struct attrlist al = {ATTR_BIT_MAP_COUNT, 0};
-	    if (getattrlist(path, &al, attrbuf, sizeof(attrbuf), FSOPT_NOFOLLOW) == 0) {
-		dp->dir = opendir_without_gvl(path);
-	    }
-	}
-#endif
-	if (dp->dir == NULL) {
-	    RB_GC_GUARD(dirname);
-	    rb_syserr_fail_path(e, orig);
-	}
+        else if (e == EIO) {
+            u_int32_t attrbuf[1];
+            struct attrlist al = {ATTR_BIT_MAP_COUNT, 0};
+            if (getattrlist(path, &al, attrbuf, sizeof(attrbuf), FSOPT_NOFOLLOW) == 0) {
+                dp->dir = opendir_without_gvl(path);
+            }
+        }
+#endif
+        if (dp->dir == NULL) {
+            RB_GC_GUARD(dirname);
+            rb_syserr_fail_path(e, orig);
+        }
     }
     RB_OBJ_WRITE(dir, &dp->path, orig);
 
@@ -630,12 +630,12 @@ dir_inspect(VALUE dir)
 
     TypedData_Get_Struct(dir, struct dir_data, &dir_data_type, dirp);
     if (!NIL_P(dirp->path)) {
-	VALUE str = rb_str_new_cstr("#<");
-	rb_str_append(str, rb_class_name(CLASS_OF(dir)));
-	rb_str_cat2(str, ":");
-	rb_str_append(str, dirp->path);
-	rb_str_cat2(str, ">");
-	return str;
+        VALUE str = rb_str_new_cstr("#<");
+        rb_str_append(str, rb_class_name(CLASS_OF(dir)));
+        rb_str_cat2(str, ":");
+        rb_str_append(str, dirp->path);
+        rb_str_cat2(str, ">");
+        return str;
     }
     return rb_funcallv(dir, idTo_s, 0, 0);
 }
@@ -677,7 +677,7 @@ dir_fileno(VALUE dir)
     GetDIR(dir, dirp);
     fd = dirfd(dirp->dir);
     if (fd == -1)
-	rb_sys_fail("dirfd");
+        rb_sys_fail("dirfd");
     return INT2NUM(fd);
 }
 #else
@@ -709,12 +709,12 @@ static int
 fundamental_encoding_p(rb_encoding *enc)
 {
     switch (rb_enc_to_index(enc)) {
-      case ENCINDEX_ASCII:
+      case ENCINDEX_ASCII_8BIT:
       case ENCINDEX_US_ASCII:
       case ENCINDEX_UTF_8:
-	return TRUE;
+        return TRUE;
       default:
-	return FALSE;
+        return FALSE;
     }
 }
 # define READDIR(dir, enc) rb_w32_readdir((dir), (enc))
@@ -731,11 +731,11 @@ to_be_skipped(const struct dirent *dp)
 #ifdef HAVE_DIRENT_NAMLEN
     switch (NAMLEN(dp)) {
       case 2:
-	if (name[1] != '.') return FALSE;
+        if (name[1] != '.') return FALSE;
       case 1:
-	return TRUE;
+        return TRUE;
       default:
-	break;
+        break;
     }
 #else
     if (!name[1]) return TRUE;
@@ -766,12 +766,12 @@ dir_read(VALUE dir)
     GetDIR(dir, dirp);
     errno = 0;
     if ((dp = READDIR(dirp->dir, dirp->enc)) != NULL) {
-	return rb_external_str_new_with_enc(dp->d_name, NAMLEN(dp), dirp->enc);
+        return rb_external_str_new_with_enc(dp->d_name, NAMLEN(dp), dirp->enc);
     }
     else {
-	int e = errno;
-	if (e != 0) rb_syserr_fail(e, 0);
-	return Qnil;		/* end of stream */
+        int e = errno;
+        if (e != 0) rb_syserr_fail(e, 0);
+        return Qnil;		/* end of stream */
     }
 }
 
@@ -821,23 +821,23 @@ dir_each_entry(VALUE dir, VALUE (*each)(VALUE, VALUE), VALUE arg, int children_o
     rewinddir(dirp->dir);
     IF_NORMALIZE_UTF8PATH(norm_p = need_normalization(dirp->dir, RSTRING_PTR(dirp->path)));
     while ((dp = READDIR(dirp->dir, dirp->enc)) != NULL) {
-	const char *name = dp->d_name;
-	size_t namlen = NAMLEN(dp);
-	VALUE path;
-
-	if (children_only && name[0] == '.') {
-	    if (namlen == 1) continue; /* current directory */
-	    if (namlen == 2 && name[1] == '.') continue; /* parent directory */
-	}
+        const char *name = dp->d_name;
+        size_t namlen = NAMLEN(dp);
+        VALUE path;
+
+        if (children_only && name[0] == '.') {
+            if (namlen == 1) continue; /* current directory */
+            if (namlen == 2 && name[1] == '.') continue; /* parent directory */
+        }
 #if NORMALIZE_UTF8PATH
-	if (norm_p && has_nonascii(name, namlen) &&
-	    !NIL_P(path = rb_str_normalize_ospath(name, namlen))) {
-	    path = rb_external_str_with_enc(path, dirp->enc);
-	}
-	else
+        if (norm_p && has_nonascii(name, namlen) &&
+            !NIL_P(path = rb_str_normalize_ospath(name, namlen))) {
+            path = rb_external_str_with_enc(path, dirp->enc);
+        }
+        else
 #endif
-	path = rb_external_str_new_with_enc(name, namlen, dirp->enc);
-	(*each)(arg, path);
+        path = rb_external_str_new_with_enc(name, namlen, dirp->enc);
+        (*each)(arg, path);
     }
     return dir;
 }
@@ -978,7 +978,7 @@ static void
 dir_chdir(VALUE path)
 {
     if (chdir(RSTRING_PTR(path)) < 0)
-	rb_sys_fail_path(path);
+        rb_sys_fail_path(path);
 }
 
 static int chdir_blocking = 0;
@@ -997,7 +997,7 @@ chdir_yield(VALUE v)
     args->done = TRUE;
     chdir_blocking++;
     if (NIL_P(chdir_thread))
-	chdir_thread = rb_thread_current();
+        chdir_thread = rb_thread_current();
     return rb_yield(args->new_path);
 }
 
@@ -1006,10 +1006,10 @@ chdir_restore(VALUE v)
 {
     struct chdir_data *args = (void *)v;
     if (args->done) {
-	chdir_blocking--;
-	if (chdir_blocking == 0)
-	    chdir_thread = Qnil;
-	dir_chdir(args->old_path);
+        chdir_blocking--;
+        if (chdir_blocking == 0)
+            chdir_thread = Qnil;
+        dir_chdir(args->old_path);
     }
     return Qnil;
 }
@@ -1063,35 +1063,35 @@ dir_s_chdir(int argc, VALUE *argv, VALUE obj)
         path = rb_str_encode_ospath(rb_get_path(argv[0]));
     }
     else {
-	const char *dist = getenv("HOME");
-	if (!dist) {
-	    dist = getenv("LOGDIR");
-	    if (!dist) rb_raise(rb_eArgError, "HOME/LOGDIR not set");
-	}
-	path = rb_str_new2(dist);
+        const char *dist = getenv("HOME");
+        if (!dist) {
+            dist = getenv("LOGDIR");
+            if (!dist) rb_raise(rb_eArgError, "HOME/LOGDIR not set");
+        }
+        path = rb_str_new2(dist);
     }
 
     if (chdir_blocking > 0) {
-	if (rb_thread_current() != chdir_thread)
+        if (rb_thread_current() != chdir_thread)
             rb_raise(rb_eRuntimeError, "conflicting chdir during another chdir block");
         if (!rb_block_given_p())
             rb_warn("conflicting chdir during another chdir block");
     }
 
     if (rb_block_given_p()) {
-	struct chdir_data args;
+        struct chdir_data args;
 
-	args.old_path = rb_str_encode_ospath(rb_dir_getwd());
-	args.new_path = path;
-	args.done = FALSE;
-	return rb_ensure(chdir_yield, (VALUE)&args, chdir_restore, (VALUE)&args);
+        args.old_path = rb_str_encode_ospath(rb_dir_getwd());
+        args.new_path = path;
+        args.done = FALSE;
+        return rb_ensure(chdir_yield, (VALUE)&args, chdir_restore, (VALUE)&args);
     }
     else {
-	char *p = RSTRING_PTR(path);
-	int r = (int)(VALUE)rb_thread_call_without_gvl(nogvl_chdir, p,
-							RUBY_UBF_IO, 0);
-	if (r < 0)
-	    rb_sys_fail_path(path);
+        char *p = RSTRING_PTR(path);
+        int r = (int)(VALUE)rb_thread_call_without_gvl(nogvl_chdir, p,
+                                                        RUBY_UBF_IO, 0);
+        if (r < 0)
+            rb_sys_fail_path(path);
     }
 
     return INT2FIX(0);
@@ -1131,12 +1131,12 @@ rb_dir_getwd(void)
 
     switch (fsenc) {
       case ENCINDEX_US_ASCII:
-	fsenc = ENCINDEX_ASCII;
-      case ENCINDEX_ASCII:
-	break;
+        fsenc = ENCINDEX_ASCII_8BIT;
+      case ENCINDEX_ASCII_8BIT:
+        break;
 #if defined _WIN32 || defined __APPLE__
       default:
-	return rb_str_conv_enc(cwd, NULL, fs);
+        return rb_str_conv_enc(cwd, NULL, fs);
 #endif
     }
     return rb_enc_associate_index(cwd, fsenc);
@@ -1174,8 +1174,8 @@ check_dirname(VALUE dir)
     pend = path + len;
     pend = rb_enc_path_end(rb_enc_path_skip_prefix(path, pend, enc), pend, enc);
     if (pend - path < len) {
-	d = rb_str_subseq(d, 0, pend - path);
-	StringValueCStr(d);
+        d = rb_str_subseq(d, 0, pend - path);
+        StringValueCStr(d);
     }
     return rb_str_encode_ospath(d);
 }
@@ -1195,7 +1195,7 @@ dir_s_chroot(VALUE dir, VALUE path)
 {
     path = check_dirname(path);
     if (chroot(RSTRING_PTR(path)) == -1)
-	rb_sys_fail_path(path);
+        rb_sys_fail_path(path);
 
     return INT2FIX(0);
 }
@@ -1238,17 +1238,17 @@ dir_s_mkdir(int argc, VALUE *argv, VALUE obj)
     int r;
 
     if (rb_scan_args(argc, argv, "11", &path, &vmode) == 2) {
-	m.mode = NUM2MODET(vmode);
+        m.mode = NUM2MODET(vmode);
     }
     else {
-	m.mode = 0777;
+        m.mode = 0777;
     }
 
     path = check_dirname(path);
     m.path = RSTRING_PTR(path);
     r = (int)(VALUE)rb_thread_call_without_gvl(nogvl_mkdir, &m, RUBY_UBF_IO, 0);
     if (r < 0)
-	rb_sys_fail_path(path);
+        rb_sys_fail_path(path);
 
     return INT2FIX(0);
 }
@@ -1280,7 +1280,7 @@ dir_s_rmdir(VALUE obj, VALUE dir)
     p = RSTRING_PTR(dir);
     r = (int)(VALUE)rb_thread_call_without_gvl(nogvl_rmdir, (void *)p, RUBY_UBF_IO, 0);
     if (r < 0)
-	rb_sys_fail_path(dir);
+        rb_sys_fail_path(dir);
 
     return INT2FIX(0);
 }
@@ -1386,8 +1386,8 @@ at_subpath(int fd, size_t baselen, const char *path)
 {
 #if USE_OPENDIR_AT
     if (fd != (int)AT_FDCWD && baselen > 0) {
-	path += baselen;
-	if (*path == '/') ++path;
+        path += baselen;
+        if (*path == '/') ++path;
     }
 #endif
     return *path ? path : ".";
@@ -1403,7 +1403,7 @@ do_stat(int fd, size_t baselen, const char *path, struct stat *pst, int flags, r
     int ret = STAT(path, pst);
 #endif
     if (ret < 0 && !to_be_ignored(errno))
-	sys_warning(path, enc);
+        sys_warning(path, enc);
 
     return ret;
 }
@@ -1418,7 +1418,7 @@ do_lstat(int fd, size_t baselen, const char *path, struct stat *pst, int flags,
     int ret = lstat(path, pst);
 #endif
     if (ret < 0 && !to_be_ignored(errno))
-	sys_warning(path, enc);
+        sys_warning(path, enc);
 
     return ret;
 }
@@ -1443,9 +1443,9 @@ static int
 gc_for_fd_with_gvl(int e)
 {
     if (vm_initialized)
-	return (int)(VALUE)rb_thread_call_with_gvl(with_gvl_gc_for_fd, &e);
+        return (int)(VALUE)rb_thread_call_with_gvl(with_gvl_gc_for_fd, &e);
     else
-	return RBOOL(rb_gc_for_fd(e));
+        return RBOOL(rb_gc_for_fd(e));
 }
 
 static void *
@@ -1457,32 +1457,32 @@ nogvl_opendir_at(void *ptr)
 #if USE_OPENDIR_AT
     const int opendir_flags = (O_RDONLY|O_CLOEXEC|
 #  ifdef O_DIRECTORY
-			       O_DIRECTORY|
+                               O_DIRECTORY|
 #  endif /* O_DIRECTORY */
-			       0);
+                               0);
     int fd = openat(oaa->basefd, oaa->path, opendir_flags);
 
     dirp = fd >= 0 ? fdopendir(fd) : 0;
     if (!dirp) {
-	int e = errno;
-
-	switch (gc_for_fd_with_gvl(e)) {
-	  default:
-	    if (fd < 0) fd = openat(oaa->basefd, oaa->path, opendir_flags);
-	    if (fd >= 0) dirp = fdopendir(fd);
-	    if (dirp) return dirp;
-
-	    e = errno;
-	    /* fallthrough*/
-	  case 0:
-	    if (fd >= 0) close(fd);
-	    errno = e;
-	}
+        int e = errno;
+
+        switch (gc_for_fd_with_gvl(e)) {
+          default:
+            if (fd < 0) fd = openat(oaa->basefd, oaa->path, opendir_flags);
+            if (fd >= 0) dirp = fdopendir(fd);
+            if (dirp) return dirp;
+
+            e = errno;
+            /* fallthrough*/
+          case 0:
+            if (fd >= 0) close(fd);
+            errno = e;
+        }
     }
 #else  /* !USE_OPENDIR_AT */
     dirp = opendir(oaa->path);
     if (!dirp && gc_for_fd_with_gvl(errno))
-	dirp = opendir(oaa->path);
+        dirp = opendir(oaa->path);
 #endif /* !USE_OPENDIR_AT */
 
     return dirp;
@@ -1497,37 +1497,37 @@ opendir_at(int basefd, const char *path)
     oaa.path = path;
 
     if (vm_initialized)
-	return rb_thread_call_without_gvl(nogvl_opendir_at, &oaa, RUBY_UBF_IO, 0);
+        return rb_thread_call_without_gvl(nogvl_opendir_at, &oaa, RUBY_UBF_IO, 0);
     else
-	return nogvl_opendir_at(&oaa);
+        return nogvl_opendir_at(&oaa);
 }
 
 static DIR *
 do_opendir(const int basefd, size_t baselen, const char *path, int flags, rb_encoding *enc,
-	   ruby_glob_errfunc *errfunc, VALUE arg, int *status)
+           ruby_glob_errfunc *errfunc, VALUE arg, int *status)
 {
     DIR *dirp;
 #ifdef _WIN32
     VALUE tmp = 0;
     if (!fundamental_encoding_p(enc)) {
-	tmp = rb_enc_str_new(path, strlen(path), enc);
-	tmp = rb_str_encode_ospath(tmp);
-	path = RSTRING_PTR(tmp);
+        tmp = rb_enc_str_new(path, strlen(path), enc);
+        tmp = rb_str_encode_ospath(tmp);
+        path = RSTRING_PTR(tmp);
     }
 #endif
     dirp = opendir_at(basefd, at_subpath(basefd, baselen, path));
     if (!dirp) {
-	int e = errno;
-
-	*status = 0;
-	if (!to_be_ignored(e)) {
-	    if (errfunc) {
-		*status = (*errfunc)(path, arg, enc, e);
-	    }
-	    else {
-		sys_warning(path, enc);
-	    }
-	}
+        int e = errno;
+
+        *status = 0;
+        if (!to_be_ignored(e)) {
+            if (errfunc) {
+                *status = (*errfunc)(path, arg, enc, e);
+            }
+            else {
+                sys_warning(path, enc);
+            }
+        }
     }
 #ifdef _WIN32
     if (tmp) rb_str_resize(tmp, 0); /* GC guard */
@@ -1550,37 +1550,37 @@ has_magic(const char *p, const char *pend, int flags, rb_encoding *enc)
     register char c;
 
     while (p < pend && (c = *p++) != 0) {
-	switch (c) {
-	  case '{':
-	    return BRACE;
+        switch (c) {
+          case '{':
+            return BRACE;
 
-	  case '*':
-	  case '?':
-	  case '[':
-	    hasmagical = 1;
-	    break;
+          case '*':
+          case '?':
+          case '[':
+            hasmagical = 1;
+            break;
 
-	  case '\\':
-	    if (escape && p++ >= pend)
-		continue;
-	    break;
+          case '\\':
+            if (escape && p++ >= pend)
+                continue;
+            break;
 
 #ifdef _WIN32
-	  case '.':
-	    break;
+          case '.':
+            break;
 
-	  case '~':
-	    hasalpha = 1;
-	    break;
+          case '~':
+            hasalpha = 1;
+            break;
 #endif
-	  default:
-	    if (IS_WIN32 || ISALPHA(c)) {
-		hasalpha = 1;
-	    }
-	    break;
-	}
+          default:
+            if (IS_WIN32 || ISALPHA(c)) {
+                hasalpha = 1;
+            }
+            break;
+        }
 
-	p = Next(p-1, pend, enc);
+        p = Next(p-1, pend, enc);
     }
 
     return hasmagical ? MAGICAL : hasalpha ? ALPHA : PLAIN;
@@ -1596,33 +1596,33 @@ find_dirsep(const char *p, const char *pend, int flags, rb_encoding *enc)
     int open = 0;
 
     while ((c = *p++) != 0) {
-	switch (c) {
-	  case '[':
-	    open = 1;
-	    continue;
-	  case ']':
-	    open = 0;
-	    continue;
-
-	  case '{':
-	    open = 1;
-	    continue;
-	  case '}':
-	    open = 0;
-	    continue;
-
-	  case '/':
-	    if (!open)
-		return (char *)p-1;
-	    continue;
-
-	  case '\\':
-	    if (escape && !(c = *p++))
-		return (char *)p-1;
-	    continue;
-	}
-
-	p = Next(p-1, pend, enc);
+        switch (c) {
+          case '[':
+            open = 1;
+            continue;
+          case ']':
+            open = 0;
+            continue;
+
+          case '{':
+            open = 1;
+            continue;
+          case '}':
+            open = 0;
+            continue;
+
+          case '/':
+            if (!open)
+                return (char *)p-1;
+            continue;
+
+          case '\\':
+            if (escape && !(c = *p++))
+                return (char *)p-1;
+            continue;
+        }
+
+        p = Next(p-1, pend, enc);
     }
 
     return (char *)p-1;
@@ -1636,20 +1636,20 @@ remove_backslashes(char *p, register const char *pend, rb_encoding *enc)
     char *s = p;
 
     while (*p) {
-	if (*p == '\\') {
-	    if (t != s)
-		memmove(t, s, p - s);
-	    t += p - s;
-	    s = ++p;
-	    if (!*p) break;
-	}
-	Inc(p, pend, enc);
+        if (*p == '\\') {
+            if (t != s)
+                memmove(t, s, p - s);
+            t += p - s;
+            s = ++p;
+            if (!*p) break;
+        }
+        Inc(p, pend, enc);
     }
 
     while (*p++);
 
     if (t != s)
-	memmove(t, s, p - s); /* move '\0' too */
+        memmove(t, s, p - s); /* move '\0' too */
 
     return p;
 }
@@ -1670,49 +1670,49 @@ glob_make_pattern(const char *p, const char *e, int flags, rb_encoding *enc)
     int recursive = 0;
 
     while (p < e && *p) {
-	tmp = GLOB_ALLOC(struct glob_pattern);
-	if (!tmp) goto error;
-	if (p + 2 < e && p[0] == '*' && p[1] == '*' && p[2] == '/') {
-	    /* fold continuous RECURSIVEs (needed in glob_helper) */
-	    do { p += 3; while (*p == '/') p++; } while (p[0] == '*' && p[1] == '*' && p[2] == '/');
-	    tmp->type = RECURSIVE;
-	    tmp->str = 0;
-	    dirsep = 1;
-	    recursive = 1;
-	}
-	else {
-	    const char *m = find_dirsep(p, e, flags, enc);
-	    const enum glob_pattern_type magic = has_magic(p, m, flags, enc);
-	    const enum glob_pattern_type non_magic = (USE_NAME_ON_FS || FNM_SYSCASE) ? PLAIN : ALPHA;
-	    char *buf;
-
-	    if (!(FNM_SYSCASE || magic > non_magic) && !recursive && *m) {
-		const char *m2;
-		while (has_magic(m+1, m2 = find_dirsep(m+1, e, flags, enc), flags, enc) <= non_magic &&
-		       *m2) {
-		    m = m2;
-		}
-	    }
-	    buf = GLOB_ALLOC_N(char, m-p+1);
-	    if (!buf) {
-		GLOB_FREE(tmp);
-		goto error;
-	    }
-	    memcpy(buf, p, m-p);
-	    buf[m-p] = '\0';
-	    tmp->type = magic > MAGICAL ? MAGICAL : magic > non_magic ? magic : PLAIN;
-	    tmp->str = buf;
-	    if (*m) {
-		dirsep = 1;
-		p = m + 1;
-	    }
-	    else {
-		dirsep = 0;
-		p = m;
-	    }
-	}
-	*tail = tmp;
-	tail = &tmp->next;
+        tmp = GLOB_ALLOC(struct glob_pattern);
+        if (!tmp) goto error;
+        if (p + 2 < e && p[0] == '*' && p[1] == '*' && p[2] == '/') {
+            /* fold continuous RECURSIVEs (needed in glob_helper) */
+            do { p += 3; while (*p == '/') p++; } while (p[0] == '*' && p[1] == '*' && p[2] == '/');
+            tmp->type = RECURSIVE;
+            tmp->str = 0;
+            dirsep = 1;
+            recursive = 1;
+        }
+        else {
+            const char *m = find_dirsep(p, e, flags, enc);
+            const enum glob_pattern_type magic = has_magic(p, m, flags, enc);
+            const enum glob_pattern_type non_magic = (USE_NAME_ON_FS || FNM_SYSCASE) ? PLAIN : ALPHA;
+            char *buf;
+
+            if (!(FNM_SYSCASE || magic > non_magic) && !recursive && *m) {
+                const char *m2;
+                while (has_magic(m+1, m2 = find_dirsep(m+1, e, flags, enc), flags, enc) <= non_magic &&
+                       *m2) {
+                    m = m2;
+                }
+            }
+            buf = GLOB_ALLOC_N(char, m-p+1);
+            if (!buf) {
+                GLOB_FREE(tmp);
+                goto error;
+            }
+            memcpy(buf, p, m-p);
+            buf[m-p] = '\0';
+            tmp->type = magic > MAGICAL ? MAGICAL : magic > non_magic ? magic : PLAIN;
+            tmp->str = buf;
+            if (*m) {
+                dirsep = 1;
+                p = m + 1;
+            }
+            else {
+                dirsep = 0;
+                p = m;
+            }
+        }
+        *tail = tmp;
+        tail = &tmp->next;
     }
 
     tmp = GLOB_ALLOC(struct glob_pattern);
@@ -1736,11 +1736,11 @@ static void
 glob_free_pattern(struct glob_pattern *list)
 {
     while (list) {
-	struct glob_pattern *tmp = list;
-	list = list->next;
-	if (tmp->str)
-	    GLOB_FREE(tmp->str);
-	GLOB_FREE(tmp);
+        struct glob_pattern *tmp = list;
+        list = list->next;
+        if (tmp->str)
+            GLOB_FREE(tmp->str);
+        GLOB_FREE(tmp);
     }
 }
 
@@ -1752,7 +1752,7 @@ join_path(const char *path, size_t len, int dirsep, const char *name, size_t nam
     if (!buf) return 0;
     memcpy(buf, path, len);
     if (dirsep) {
-	buf[len++] = '/';
+        buf[len++] = '/';
     }
     memcpy(buf+len, name, namlen);
     buf[len+namlen] = '\0';
@@ -1769,8 +1769,8 @@ static int
 is_case_sensitive(DIR *dirp, const char *path)
 {
     struct {
-	u_int32_t length;
-	vol_capabilities_attr_t cap[1];
+        u_int32_t length;
+        vol_capabilities_attr_t cap[1];
     } __attribute__((aligned(4), packed)) attrbuf[1];
     struct attrlist al = {ATTR_BIT_MAP_COUNT, 0, 0, ATTR_VOL_INFO|ATTR_VOL_CAPABILITIES};
     const vol_capabilities_attr_t *const cap = attrbuf[0].cap;
@@ -1779,13 +1779,13 @@ is_case_sensitive(DIR *dirp, const char *path)
 
 #   if defined HAVE_FGETATTRLIST
     if (fgetattrlist(dirfd(dirp), &al, attrbuf, sizeof(attrbuf), FSOPT_NOFOLLOW))
-	return -1;
+        return -1;
 #   else
     if (getattrlist(path, &al, attrbuf, sizeof(attrbuf), FSOPT_NOFOLLOW))
-	return -1;
+        return -1;
 #   endif
     if (!(cap->valid[idx] & mask))
-	return -1;
+        return -1;
     return (cap->capabilities[idx] & mask) != 0;
 }
 
@@ -1793,10 +1793,10 @@ static char *
 replace_real_basename(char *path, long base, rb_encoding *enc, int norm_p, int flags, rb_pathtype_t *type)
 {
     struct {
-	u_int32_t length;
-	attrreference_t ref[1];
-	fsobj_type_t objtype;
-	char path[MAXPATHLEN * 3];
+        u_int32_t length;
+        attrreference_t ref[1];
+        fsobj_type_t objtype;
+        char path[MAXPATHLEN * 3];
     } __attribute__((aligned(4), packed)) attrbuf[1];
     struct attrlist al = {ATTR_BIT_MAP_COUNT, 0, ATTR_CMN_NAME|ATTR_CMN_OBJTYPE};
     const attrreference_t *const ar = attrbuf[0].ref;
@@ -1807,9 +1807,9 @@ replace_real_basename(char *path, long base, rb_encoding *enc, int norm_p, int f
 
     *type = path_noent;
     if (getattrlist(path, &al, attrbuf, sizeof(attrbuf), FSOPT_NOFOLLOW)) {
-	if (!to_be_ignored(errno))
-	    sys_warning(path, enc);
-	return path;
+        if (!to_be_ignored(errno))
+            sys_warning(path, enc);
+        return path;
     }
 
     switch (attrbuf[0].objtype) {
@@ -1821,21 +1821,21 @@ replace_real_basename(char *path, long base, rb_encoding *enc, int norm_p, int f
     name = (char *)ar + ar->attr_dataoffset;
     len = (long)ar->attr_length - 1;
     if (name + len > (char *)attrbuf + sizeof(attrbuf))
-	return path;
+        return path;
 
 # if NORMALIZE_UTF8PATH
     if (norm_p && has_nonascii(name, len)) {
-	if (!NIL_P(utf8str = rb_str_normalize_ospath(name, len))) {
-	    RSTRING_GETMEM(utf8str, name, len);
-	}
+        if (!NIL_P(utf8str = rb_str_normalize_ospath(name, len))) {
+            RSTRING_GETMEM(utf8str, name, len);
+        }
     }
 # endif
 
     tmp = GLOB_REALLOC(path, base + len + 1);
     if (tmp) {
-	path = tmp;
-	memcpy(path + base, name, len);
-	path[base + len] = '\0';
+        path = tmp;
+        memcpy(path + base, name, len);
+        path[base + len] = '\0';
     }
     IF_NORMALIZE_UTF8PATH(if (!NIL_P(utf8str)) rb_str_resize(utf8str, 0));
     return path;
@@ -1856,62 +1856,62 @@ replace_real_basename(char *path, long base, rb_encoding *enc, int norm_p, int f
     long wlen;
     int e = 0;
     if (!fundamental_encoding_p(enc)) {
-	tmp = rb_enc_str_new_cstr(plainname, enc);
-	tmp = rb_str_encode_ospath(tmp);
-	plainname = RSTRING_PTR(tmp);
+        tmp = rb_enc_str_new_cstr(plainname, enc);
+        tmp = rb_str_encode_ospath(tmp);
+        plainname = RSTRING_PTR(tmp);
     }
     wplain = rb_w32_mbstr_to_wstr(CP_UTF8, plainname, -1, &wlen);
     if (tmp) rb_str_resize(tmp, 0);
     if (!wplain) return path;
     if (GetFileAttributesExW(wplain, GetFileExInfoStandard, &fa)) {
-	h = FindFirstFileW(wplain, &fd);
-	e = rb_w32_map_errno(GetLastError());
+        h = FindFirstFileW(wplain, &fd);
+        e = rb_w32_map_errno(GetLastError());
     }
     if (fa.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) {
-	if (!rb_w32_reparse_symlink_p(wplain))
-	    fa.dwFileAttributes &= ~FILE_ATTRIBUTE_REPARSE_POINT;
+        if (!rb_w32_reparse_symlink_p(wplain))
+            fa.dwFileAttributes &= ~FILE_ATTRIBUTE_REPARSE_POINT;
     }
     free(wplain);
     if (h == INVALID_HANDLE_VALUE) {
-	*type = path_noent;
-	if (e && !to_be_ignored(e)) {
-	    errno = e;
-	    sys_warning(path, enc);
-	}
-	return path;
+        *type = path_noent;
+        if (e && !to_be_ignored(e)) {
+            errno = e;
+            sys_warning(path, enc);
+        }
+        return path;
     }
     FindClose(h);
     *type =
-	(fa.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) ? path_symlink :
-	(fa.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) ? path_directory :
-	path_regular;
+        (fa.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) ? path_symlink :
+        (fa.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) ? path_directory :
+        path_regular;
     if (tmp) {
-	char *buf;
-	tmp = rb_w32_conv_from_wchar(fd.cFileName, enc);
-	wlen = RSTRING_LEN(tmp);
-	buf = GLOB_REALLOC(path, base + wlen + 1);
-	if (buf) {
-	    path = buf;
-	    memcpy(path + base, RSTRING_PTR(tmp), wlen);
-	    path[base + wlen] = 0;
-	}
-	rb_str_resize(tmp, 0);
+        char *buf;
+        tmp = rb_w32_conv_from_wchar(fd.cFileName, enc);
+        wlen = RSTRING_LEN(tmp);
+        buf = GLOB_REALLOC(path, base + wlen + 1);
+        if (buf) {
+            path = buf;
+            memcpy(path + base, RSTRING_PTR(tmp), wlen);
+            path[base + wlen] = 0;
+        }
+        rb_str_resize(tmp, 0);
     }
     else {
-	char *utf8filename;
-	wlen = WideCharToMultiByte(CP_UTF8, 0, fd.cFileName, -1, NULL, 0, NULL, NULL);
-	utf8filename = GLOB_REALLOC(0, wlen);
-	if (utf8filename) {
-	    char *buf;
-	    WideCharToMultiByte(CP_UTF8, 0, fd.cFileName, -1, utf8filename, wlen, NULL, NULL);
-	    buf = GLOB_REALLOC(path, base + wlen + 1);
-	    if (buf) {
-		path = buf;
-		memcpy(path + base, utf8filename, wlen);
-		path[base + wlen] = 0;
-	    }
-	    GLOB_FREE(utf8filename);
-	}
+        char *utf8filename;
+        wlen = WideCharToMultiByte(CP_UTF8, 0, fd.cFileName, -1, NULL, 0, NULL, NULL);
+        utf8filename = GLOB_REALLOC(0, wlen);
+        if (utf8filename) {
+            char *buf;
+            WideCharToMultiByte(CP_UTF8, 0, fd.cFileName, -1, utf8filename, wlen, NULL, NULL);
+            buf = GLOB_REALLOC(path, base + wlen + 1);
+            if (buf) {
+                path = buf;
+                memcpy(path + base, utf8filename, wlen);
+                path[base + wlen] = 0;
+            }
+            GLOB_FREE(utf8filename);
+        }
     }
     return path;
 }
@@ -2003,7 +2003,7 @@ rb_glob_error(const char *path, VALUE a, const void *enc, int error)
 #ifdef ENOTCAPABLE
       case ENOTCAPABLE:
 #endif
-	errfunc = glob_func_warning;
+        errfunc = glob_func_warning;
     }
     args.path = path;
     args.enc = enc;
@@ -2027,7 +2027,7 @@ dirent_match(const char *pat, rb_encoding *enc, const char *name, const rb_diren
     if (fnmatch(pat, enc, name, flags) == 0) return 1;
 #ifdef _WIN32
     if (dp->d_altname && (flags & FNM_SHORTNAME)) {
-	if (fnmatch(pat, enc, dp->d_altname, flags) == 0) return 1;
+        if (fnmatch(pat, enc, dp->d_altname, flags) == 0) return 1;
     }
 #endif
     return 0;
@@ -2068,39 +2068,39 @@ join_path_from_pattern(struct glob_pattern **beg)
     size_t path_len = 0;
 
     for (p = *beg; p; p = p->next) {
-	const char *str;
-	switch (p->type) {
-	  case RECURSIVE:
-	    str = "**";
-	    break;
-	  case MATCH_DIR:
-	    /* append last slash */
-	    str = "";
-	    break;
-	  default:
-	    str = p->str;
-	    if (!str) continue;
-	}
-	if (!path) {
-	    path_len = strlen(str);
-	    path = GLOB_ALLOC_N(char, path_len + 1);
+        const char *str;
+        switch (p->type) {
+          case RECURSIVE:
+            str = "**";
+            break;
+          case MATCH_DIR:
+            /* append last slash */
+            str = "";
+            break;
+          default:
+            str = p->str;
+            if (!str) continue;
+        }
+        if (!path) {
+            path_len = strlen(str);
+            path = GLOB_ALLOC_N(char, path_len + 1);
             if (path) {
                 memcpy(path, str, path_len);
                 path[path_len] = '\0';
             }
         }
         else {
-	    size_t len = strlen(str);
-	    char *tmp;
-	    tmp = GLOB_REALLOC(path, path_len + len + 2);
-	    if (tmp) {
-		path = tmp;
-		path[path_len++] = '/';
-		memcpy(path + path_len, str, len);
-		path_len += len;
-		path[path_len] = '\0';
-	    }
-	}
+            size_t len = strlen(str);
+            char *tmp;
+            tmp = GLOB_REALLOC(path, path_len + len + 2);
+            if (tmp) {
+                path = tmp;
+                path[path_len++] = '/';
+                memcpy(path + path_len, str, len);
+                path_len += len;
+                path[path_len] = '\0';
+            }
+        }
     }
     return path;
 }
@@ -2108,7 +2108,7 @@ join_path_from_pattern(struct glob_pattern **beg)
 static int push_caller(const char *path, VALUE val, void *enc);
 
 static int ruby_brace_expand(const char *str, int flags, ruby_glob_func *func, VALUE arg,
-			     rb_encoding *enc, VALUE var);
+                             rb_encoding *enc, VALUE var);
 
 static const size_t rb_dirent_name_offset =
     offsetof(rb_dirent_t, d_type) + sizeof(uint8_t);
@@ -2216,7 +2216,7 @@ glob_opendir(ruby_glob_entries_t *ent, DIR *dirp, int flags, rb_encoding *enc)
             ent->sort.entries = newp;
         }
 #endif
-	while ((dp = READDIR(dirp, enc)) != NULL) {
+        while ((dp = READDIR(dirp, enc)) != NULL) {
             rb_dirent_t *rdp = dirent_copy(dp, NULL);
             if (!rdp) {
                 goto nomem;
@@ -2288,133 +2288,133 @@ glob_helper(
     rb_check_stack_overflow();
 
     for (cur = beg; cur < end; ++cur) {
-	struct glob_pattern *p = *cur;
-	if (p->type == RECURSIVE) {
-	    recursive = 1;
-	    p = p->next;
-	}
-	switch (p->type) {
-	  case PLAIN:
-	    plain = 1;
-	    break;
-	  case ALPHA:
+        struct glob_pattern *p = *cur;
+        if (p->type == RECURSIVE) {
+            recursive = 1;
+            p = p->next;
+        }
+        switch (p->type) {
+          case PLAIN:
+            plain = 1;
+            break;
+          case ALPHA:
 #if USE_NAME_ON_FS == USE_NAME_ON_FS_REAL_BASENAME
-	    plain = 1;
+            plain = 1;
 #else
-	    magical = 1;
-#endif
-	    break;
-	  case BRACE:
-	    if (!recursive) {
-		brace = 1;
-	    }
-	    break;
-	  case MAGICAL:
-	    magical = 2;
-	    break;
-	  case MATCH_ALL:
-	    match_all = 1;
-	    break;
-	  case MATCH_DIR:
-	    match_dir = 1;
-	    break;
-	  case RECURSIVE:
-	    rb_bug("continuous RECURSIVEs");
-	}
+            magical = 1;
+#endif
+            break;
+          case BRACE:
+            if (!recursive || strchr(p->str, '/')) {
+                brace = 1;
+            }
+            break;
+          case MAGICAL:
+            magical = 2;
+            break;
+          case MATCH_ALL:
+            match_all = 1;
+            break;
+          case MATCH_DIR:
+            match_dir = 1;
+            break;
+          case RECURSIVE:
+            rb_bug("continuous RECURSIVEs");
+        }
     }
 
     if (brace) {
-	struct push_glob_args args;
-	char* brace_path = join_path_from_pattern(beg);
-	if (!brace_path) return -1;
-	args.fd = fd;
-	args.path = path;
-	args.baselen = baselen;
-	args.namelen = namelen;
-	args.dirsep = dirsep;
-	args.pathtype = pathtype;
-	args.flags = flags;
-	args.funcs = funcs;
-	args.arg = arg;
-	status = ruby_brace_expand(brace_path, flags, push_caller, (VALUE)&args, enc, Qfalse);
-	GLOB_FREE(brace_path);
-	return status;
+        struct push_glob_args args;
+        char* brace_path = join_path_from_pattern(beg);
+        if (!brace_path) return -1;
+        args.fd = fd;
+        args.path = path;
+        args.baselen = baselen;
+        args.namelen = namelen;
+        args.dirsep = dirsep;
+        args.pathtype = pathtype;
+        args.flags = flags;
+        args.funcs = funcs;
+        args.arg = arg;
+        status = ruby_brace_expand(brace_path, flags, push_caller, (VALUE)&args, enc, Qfalse);
+        GLOB_FREE(brace_path);
+        return status;
     }
 
     if (*path) {
-	if (match_all && pathtype == path_unknown) {
-	    if (do_lstat(fd, baselen, path, &st, flags, enc) == 0) {
-		pathtype = IFTODT(st.st_mode);
-	    }
-	    else {
-		pathtype = path_noent;
-	    }
-	}
-	if (match_dir && (pathtype == path_unknown || pathtype == path_symlink)) {
-	    if (do_stat(fd, baselen, path, &st, flags, enc) == 0) {
-		pathtype = IFTODT(st.st_mode);
-	    }
-	    else {
-		pathtype = path_noent;
-	    }
-	}
-	if (match_all && pathtype > path_noent) {
-	    const char *subpath = path + baselen + (baselen && path[baselen] == '/');
-	    status = glob_call_func(funcs->match, subpath, arg, enc);
-	    if (status) return status;
-	}
-	if (match_dir && pathtype == path_directory) {
-	    int seplen = (baselen && path[baselen] == '/');
-	    const char *subpath = path + baselen + seplen;
-	    char *tmp = join_path(subpath, namelen - seplen, dirsep, "", 0);
-	    if (!tmp) return -1;
-	    status = glob_call_func(funcs->match, tmp, arg, enc);
-	    GLOB_FREE(tmp);
-	    if (status) return status;
-	}
+        if (match_all && pathtype == path_unknown) {
+            if (do_lstat(fd, baselen, path, &st, flags, enc) == 0) {
+                pathtype = IFTODT(st.st_mode);
+            }
+            else {
+                pathtype = path_noent;
+            }
+        }
+        if (match_dir && (pathtype == path_unknown || pathtype == path_symlink)) {
+            if (do_stat(fd, baselen, path, &st, flags, enc) == 0) {
+                pathtype = IFTODT(st.st_mode);
+            }
+            else {
+                pathtype = path_noent;
+            }
+        }
+        if (match_all && pathtype > path_noent) {
+            const char *subpath = path + baselen + (baselen && path[baselen] == '/');
+            status = glob_call_func(funcs->match, subpath, arg, enc);
+            if (status) return status;
+        }
+        if (match_dir && pathtype == path_directory) {
+            int seplen = (baselen && path[baselen] == '/');
+            const char *subpath = path + baselen + seplen;
+            char *tmp = join_path(subpath, namelen - seplen, dirsep, "", 0);
+            if (!tmp) return -1;
+            status = glob_call_func(funcs->match, tmp, arg, enc);
+            GLOB_FREE(tmp);
+            if (status) return status;
+        }
     }
 
     if (pathtype == path_noent) return 0;
 
     if (magical || recursive) {
-	rb_dirent_t *dp;
-	DIR *dirp;
+        rb_dirent_t *dp;
+        DIR *dirp;
 # if USE_NAME_ON_FS == USE_NAME_ON_FS_BY_FNMATCH
-	char *plainname = 0;
+        char *plainname = 0;
 # endif
-	IF_NORMALIZE_UTF8PATH(int norm_p);
+        IF_NORMALIZE_UTF8PATH(int norm_p);
 # if USE_NAME_ON_FS == USE_NAME_ON_FS_BY_FNMATCH
-	if (cur + 1 == end && (*cur)->type <= ALPHA) {
-	    plainname = join_path(path, pathlen, dirsep, (*cur)->str, strlen((*cur)->str));
-	    if (!plainname) return -1;
-	    dirp = do_opendir(fd, basename, plainname, flags, enc, funcs->error, arg, &status);
-	    GLOB_FREE(plainname);
-	}
-	else
+        if (cur + 1 == end && (*cur)->type <= ALPHA) {
+            plainname = join_path(path, pathlen, dirsep, (*cur)->str, strlen((*cur)->str));
+            if (!plainname) return -1;
+            dirp = do_opendir(fd, basename, plainname, flags, enc, funcs->error, arg, &status);
+            GLOB_FREE(plainname);
+        }
+        else
 # else
-	    ;
+            ;
 # endif
-	dirp = do_opendir(fd, baselen, path, flags, enc, funcs->error, arg, &status);
-	if (dirp == NULL) {
+        dirp = do_opendir(fd, baselen, path, flags, enc, funcs->error, arg, &status);
+        if (dirp == NULL) {
 # if FNM_SYSCASE || NORMALIZE_UTF8PATH
-	    if ((magical < 2) && !recursive && (errno == EACCES)) {
-		/* no read permission, fallback */
-		goto literally;
-	    }
+            if ((magical < 2) && !recursive && (errno == EACCES)) {
+                /* no read permission, fallback */
+                goto literally;
+            }
 # endif
-	    return status;
-	}
-	IF_NORMALIZE_UTF8PATH(norm_p = need_normalization(dirp, *path ? path : "."));
+            return status;
+        }
+        IF_NORMALIZE_UTF8PATH(norm_p = need_normalization(dirp, *path ? path : "."));
 
 # if NORMALIZE_UTF8PATH
-	if (!(norm_p || magical || recursive)) {
-	    closedir(dirp);
-	    goto literally;
-	}
+        if (!(norm_p || magical || recursive)) {
+            closedir(dirp);
+            goto literally;
+        }
 # endif
 # ifdef HAVE_GETATTRLIST
-	if (is_case_sensitive(dirp, path) == 0)
-	    flags |= FNM_CASEFOLD;
+        if (is_case_sensitive(dirp, path) == 0)
+            flags |= FNM_CASEFOLD;
 # endif
         ruby_glob_entries_t globent;
         if (!glob_opendir(&globent, dirp, flags, enc)) {
@@ -2428,182 +2428,182 @@ glob_helper(
             return status;
         }
 
-	int skipdot = (flags & FNM_GLOB_SKIPDOT);
-	flags |= FNM_GLOB_SKIPDOT;
-
-	while ((dp = glob_getent(&globent, flags, enc)) != NULL) {
-	    char *buf;
-	    rb_pathtype_t new_pathtype = path_unknown;
-	    const char *name;
-	    size_t namlen;
-	    int dotfile = 0;
-	    IF_NORMALIZE_UTF8PATH(VALUE utf8str = Qnil);
-
-	    name = dp->d_name;
-	    namlen = dp->d_namlen;
-	    if (name[0] == '.') {
-		++dotfile;
-		if (namlen == 1) {
-		    /* unless DOTMATCH, skip current directories not to recurse infinitely */
-		    if (recursive && !(flags & FNM_DOTMATCH)) continue;
-		    if (skipdot) continue;
-		    ++dotfile;
-		    new_pathtype = path_directory; /* force to skip stat/lstat */
-		}
-		else if (namlen == 2 && name[1] == '.') {
-		    /* always skip parent directories not to recurse infinitely */
-		    continue;
-		}
-	    }
+        int skipdot = (flags & FNM_GLOB_SKIPDOT);
+        flags |= FNM_GLOB_SKIPDOT;
+
+        while ((dp = glob_getent(&globent, flags, enc)) != NULL) {
+            char *buf;
+            rb_pathtype_t new_pathtype = path_unknown;
+            const char *name;
+            size_t namlen;
+            int dotfile = 0;
+            IF_NORMALIZE_UTF8PATH(VALUE utf8str = Qnil);
+
+            name = dp->d_name;
+            namlen = dp->d_namlen;
+            if (name[0] == '.') {
+                ++dotfile;
+                if (namlen == 1) {
+                    /* unless DOTMATCH, skip current directories not to recurse infinitely */
+                    if (recursive && !(flags & FNM_DOTMATCH)) continue;
+                    if (skipdot) continue;
+                    ++dotfile;
+                    new_pathtype = path_directory; /* force to skip stat/lstat */
+                }
+                else if (namlen == 2 && name[1] == '.') {
+                    /* always skip parent directories not to recurse infinitely */
+                    continue;
+                }
+            }
 
 # if NORMALIZE_UTF8PATH
-	    if (norm_p && has_nonascii(name, namlen)) {
-		if (!NIL_P(utf8str = rb_str_normalize_ospath(name, namlen))) {
-		    RSTRING_GETMEM(utf8str, name, namlen);
-		}
-	    }
+            if (norm_p && has_nonascii(name, namlen)) {
+                if (!NIL_P(utf8str = rb_str_normalize_ospath(name, namlen))) {
+                    RSTRING_GETMEM(utf8str, name, namlen);
+                }
+            }
 # endif
-	    buf = join_path(path, pathlen, dirsep, name, namlen);
-	    IF_NORMALIZE_UTF8PATH(if (!NIL_P(utf8str)) rb_str_resize(utf8str, 0));
-	    if (!buf) {
-		status = -1;
-		break;
-	    }
-	    name = buf + pathlen + (dirsep != 0);
+            buf = join_path(path, pathlen, dirsep, name, namlen);
+            IF_NORMALIZE_UTF8PATH(if (!NIL_P(utf8str)) rb_str_resize(utf8str, 0));
+            if (!buf) {
+                status = -1;
+                break;
+            }
+            name = buf + pathlen + (dirsep != 0);
 #if !EMULATE_IFTODT
-	    if (dp->d_type != DT_UNKNOWN) {
-		/* Got it. We need no more lstat. */
-		new_pathtype = dp->d_type;
-	    }
-#endif
-	    if (recursive && dotfile < ((flags & FNM_DOTMATCH) ? 2 : 1) &&
-		new_pathtype == path_unknown) {
-		/* RECURSIVE never match dot files unless FNM_DOTMATCH is set */
-		if (do_lstat(fd, baselen, buf, &st, flags, enc) == 0)
-		    new_pathtype = IFTODT(st.st_mode);
-		else
-		    new_pathtype = path_noent;
-	    }
-
-	    new_beg = new_end = GLOB_ALLOC_N(struct glob_pattern *, (end - beg) * 2);
-	    if (!new_beg) {
-		GLOB_FREE(buf);
-		status = -1;
-		break;
-	    }
-
-	    for (cur = beg; cur < end; ++cur) {
-		struct glob_pattern *p = *cur;
-		struct dirent_brace_args args;
-		if (p->type == RECURSIVE) {
-		    if (new_pathtype == path_directory || /* not symlink but real directory */
-			new_pathtype == path_exist) {
-			if (dotfile < ((flags & FNM_DOTMATCH) ? 2 : 1))
-			    *new_end++ = p; /* append recursive pattern */
-		    }
-		    p = p->next; /* 0 times recursion */
-		}
-		switch (p->type) {
-		  case BRACE:
-		    args.name = name;
-		    args.dp = dp;
-		    args.flags = flags;
-		    if (ruby_brace_expand(p->str, flags, dirent_match_brace,
-					  (VALUE)&args, enc, Qfalse) > 0)
-			*new_end++ = p->next;
-		    break;
-		  case ALPHA:
+            if (dp->d_type != DT_UNKNOWN) {
+                /* Got it. We need no more lstat. */
+                new_pathtype = dp->d_type;
+            }
+#endif
+            if (recursive && dotfile < ((flags & FNM_DOTMATCH) ? 2 : 1) &&
+                new_pathtype == path_unknown) {
+                /* RECURSIVE never match dot files unless FNM_DOTMATCH is set */
+                if (do_lstat(fd, baselen, buf, &st, flags, enc) == 0)
+                    new_pathtype = IFTODT(st.st_mode);
+                else
+                    new_pathtype = path_noent;
+            }
+
+            new_beg = new_end = GLOB_ALLOC_N(struct glob_pattern *, (end - beg) * 2);
+            if (!new_beg) {
+                GLOB_FREE(buf);
+                status = -1;
+                break;
+            }
+
+            for (cur = beg; cur < end; ++cur) {
+                struct glob_pattern *p = *cur;
+                struct dirent_brace_args args;
+                if (p->type == RECURSIVE) {
+                    if (new_pathtype == path_directory || /* not symlink but real directory */
+                        new_pathtype == path_exist) {
+                        if (dotfile < ((flags & FNM_DOTMATCH) ? 2 : 1))
+                            *new_end++ = p; /* append recursive pattern */
+                    }
+                    p = p->next; /* 0 times recursion */
+                }
+                switch (p->type) {
+                  case BRACE:
+                    args.name = name;
+                    args.dp = dp;
+                    args.flags = flags;
+                    if (ruby_brace_expand(p->str, flags, dirent_match_brace,
+                                          (VALUE)&args, enc, Qfalse) > 0)
+                        *new_end++ = p->next;
+                    break;
+                  case ALPHA:
 # if USE_NAME_ON_FS == USE_NAME_ON_FS_BY_FNMATCH
-		    if (plainname) {
-			*new_end++ = p->next;
-			break;
-		    }
+                    if (plainname) {
+                        *new_end++ = p->next;
+                        break;
+                    }
 # endif
-		  case PLAIN:
-		  case MAGICAL:
-		    if (dirent_match(p->str, enc, name, dp, flags))
-			*new_end++ = p->next;
-		  default:
-		    break;
-		}
-	    }
-
-	    status = glob_helper(fd, buf, baselen, name - buf - baselen + namlen, 1,
-				 new_pathtype, new_beg, new_end,
-				 flags, funcs, arg, enc);
-	    GLOB_FREE(buf);
-	    GLOB_FREE(new_beg);
-	    if (status) break;
-	}
+                  case PLAIN:
+                  case MAGICAL:
+                    if (dirent_match(p->str, enc, name, dp, flags))
+                        *new_end++ = p->next;
+                  default:
+                    break;
+                }
+            }
+
+            status = glob_helper(fd, buf, baselen, name - buf - baselen + namlen, 1,
+                                 new_pathtype, new_beg, new_end,
+                                 flags, funcs, arg, enc);
+            GLOB_FREE(buf);
+            GLOB_FREE(new_beg);
+            if (status) break;
+        }
 
         glob_dir_finish(&globent, flags);
     }
     else if (plain) {
-	struct glob_pattern **copy_beg, **copy_end, **cur2;
+        struct glob_pattern **copy_beg, **copy_end, **cur2;
 
 # if FNM_SYSCASE || NORMALIZE_UTF8PATH
       literally:
 # endif
-	copy_beg = copy_end = GLOB_ALLOC_N(struct glob_pattern *, end - beg);
-	if (!copy_beg) return -1;
-	for (cur = beg; cur < end; ++cur)
-	    *copy_end++ = (*cur)->type <= ALPHA ? *cur : 0;
-
-	for (cur = copy_beg; cur < copy_end; ++cur) {
-	    if (*cur) {
-		rb_pathtype_t new_pathtype = path_unknown;
-		char *buf;
-		char *name;
-		size_t len = strlen((*cur)->str) + 1;
-		name = GLOB_ALLOC_N(char, len);
-		if (!name) {
-		    status = -1;
-		    break;
-		}
-		memcpy(name, (*cur)->str, len);
-		if (escape)
-		    len = remove_backslashes(name, name+len-1, enc) - name;
-
-		new_beg = new_end = GLOB_ALLOC_N(struct glob_pattern *, end - beg);
-		if (!new_beg) {
-		    GLOB_FREE(name);
-		    status = -1;
-		    break;
-		}
-		*new_end++ = (*cur)->next;
-		for (cur2 = cur + 1; cur2 < copy_end; ++cur2) {
-		    if (*cur2 && fnmatch((*cur2)->str, enc, name, flags) == 0) {
-			*new_end++ = (*cur2)->next;
-			*cur2 = 0;
-		    }
-		}
-
-		buf = join_path(path, pathlen, dirsep, name, len);
-		GLOB_FREE(name);
-		if (!buf) {
-		    GLOB_FREE(new_beg);
-		    status = -1;
-		    break;
-		}
+        copy_beg = copy_end = GLOB_ALLOC_N(struct glob_pattern *, end - beg);
+        if (!copy_beg) return -1;
+        for (cur = beg; cur < end; ++cur)
+            *copy_end++ = (*cur)->type <= ALPHA ? *cur : 0;
+
+        for (cur = copy_beg; cur < copy_end; ++cur) {
+            if (*cur) {
+                rb_pathtype_t new_pathtype = path_unknown;
+                char *buf;
+                char *name;
+                size_t len = strlen((*cur)->str) + 1;
+                name = GLOB_ALLOC_N(char, len);
+                if (!name) {
+                    status = -1;
+                    break;
+                }
+                memcpy(name, (*cur)->str, len);
+                if (escape)
+                    len = remove_backslashes(name, name+len-1, enc) - name;
+
+                new_beg = new_end = GLOB_ALLOC_N(struct glob_pattern *, end - beg);
+                if (!new_beg) {
+                    GLOB_FREE(name);
+                    status = -1;
+                    break;
+                }
+                *new_end++ = (*cur)->next;
+                for (cur2 = cur + 1; cur2 < copy_end; ++cur2) {
+                    if (*cur2 && fnmatch((*cur2)->str, enc, name, flags) == 0) {
+                        *new_end++ = (*cur2)->next;
+                        *cur2 = 0;
+                    }
+                }
+
+                buf = join_path(path, pathlen, dirsep, name, len);
+                GLOB_FREE(name);
+                if (!buf) {
+                    GLOB_FREE(new_beg);
+                    status = -1;
+                    break;
+                }
 #if USE_NAME_ON_FS == USE_NAME_ON_FS_REAL_BASENAME
-		if ((*cur)->type == ALPHA) {
-		    buf = replace_real_basename(buf, pathlen + (dirsep != 0), enc,
-						IF_NORMALIZE_UTF8PATH(1)+0,
-						flags, &new_pathtype);
-		    if (!buf) break;
-		}
-#endif
-		status = glob_helper(fd, buf, baselen,
-				     namelen + strlen(buf + pathlen), 1,
-				     new_pathtype, new_beg, new_end,
-				     flags, funcs, arg, enc);
-		GLOB_FREE(buf);
-		GLOB_FREE(new_beg);
-		if (status) break;
-	    }
-	}
-
-	GLOB_FREE(copy_beg);
+                if ((*cur)->type == ALPHA) {
+                    buf = replace_real_basename(buf, pathlen + (dirsep != 0), enc,
+                                                IF_NORMALIZE_UTF8PATH(1)+0,
+                                                flags, &new_pathtype);
+                    if (!buf) break;
+                }
+#endif
+                status = glob_helper(fd, buf, baselen,
+                                     namelen + strlen(buf + pathlen), 1,
+                                     new_pathtype, new_beg, new_end,
+                                     flags, funcs, arg, enc);
+                GLOB_FREE(buf);
+                GLOB_FREE(new_beg);
+                if (status) break;
+            }
+        }
+
+        GLOB_FREE(copy_beg);
     }
 
     return status;
@@ -2618,11 +2618,11 @@ push_caller(const char *path, VALUE val, void *enc)
 
     list = glob_make_pattern(path, path + strlen(path), arg->flags, enc);
     if (!list) {
-	return -1;
+        return -1;
     }
     status = glob_helper(arg->fd, arg->path, arg->baselen, arg->namelen, arg->dirsep,
-			 arg->pathtype, &list, &list + 1, arg->flags, arg->funcs,
-			 arg->arg, enc);
+                         arg->pathtype, &list, &list + 1, arg->flags, arg->funcs,
+                         arg->arg, enc);
     glob_free_pattern(list);
     return status;
 }
@@ -2647,8 +2647,8 @@ push_glob0_caller(const char *path, VALUE val, void *enc)
 
 static int
 ruby_glob0(const char *path, int fd, const char *base, int flags,
-	   const ruby_glob_funcs_t *funcs, VALUE arg,
-	   rb_encoding *enc)
+           const ruby_glob_funcs_t *funcs, VALUE arg,
+           rb_encoding *enc)
 {
     struct glob_pattern *list;
     const char *root, *start;
@@ -2677,10 +2677,10 @@ ruby_glob0(const char *path, int fd, const char *base, int flags,
 
     n = root - start;
     if (!n && base) {
-	n = strlen(base);
-	baselen = n;
-	start = base;
-	dirsep = TRUE;
+        n = strlen(base);
+        baselen = n;
+        start = base;
+        dirsep = TRUE;
     }
     buf = GLOB_ALLOC_N(char, n + 1);
     if (!buf) return -1;
@@ -2689,12 +2689,12 @@ ruby_glob0(const char *path, int fd, const char *base, int flags,
 
     list = glob_make_pattern(root, root + strlen(root), flags, enc);
     if (!list) {
-	GLOB_FREE(buf);
-	return -1;
+        GLOB_FREE(buf);
+        return -1;
     }
     status = glob_helper(fd, buf, baselen, n-baselen, dirsep,
-			 path_unknown, &list, &list + 1,
-			 flags, funcs, arg, enc);
+                         path_unknown, &list, &list + 1,
+                         flags, funcs, arg, enc);
     glob_free_pattern(list);
     GLOB_FREE(buf);
 
@@ -2708,7 +2708,7 @@ ruby_glob(const char *path, int flags, ruby_glob_func *func, VALUE arg)
     funcs.match = func;
     funcs.error = 0;
     return ruby_glob0(path, AT_FDCWD, 0, flags & ~GLOB_VERBOSE,
-		      &funcs, arg, rb_ascii8bit_encoding());
+                      &funcs, arg, rb_ascii8bit_encoding());
 }
 
 static int
@@ -2737,7 +2737,7 @@ rb_glob(const char *path, void (*func)(const char *, VALUE, void *), VALUE arg)
     args.enc = rb_ascii8bit_encoding();
 
     status = ruby_glob0(path, AT_FDCWD, 0, GLOB_VERBOSE, &rb_glob_funcs,
-			(VALUE)&args, args.enc);
+                        (VALUE)&args, args.enc);
     if (status) GLOB_JUMP_TAG(status);
 }
 
@@ -2756,7 +2756,7 @@ push_pattern(const char *path, VALUE ary, void *enc)
 
 static int
 ruby_brace_expand(const char *str, int flags, ruby_glob_func *func, VALUE arg,
-		  rb_encoding *enc, VALUE var)
+                  rb_encoding *enc, VALUE var)
 {
     const int escape = !(flags & FNM_NOESCAPE);
     const char *p = str;
@@ -2766,48 +2766,48 @@ ruby_brace_expand(const char *str, int flags, ruby_glob_func *func, VALUE arg,
     int nest = 0, status = 0;
 
     while (*p) {
-	if (*p == '{' && nest++ == 0) {
-	    lbrace = p;
-	}
-	if (*p == '}' && lbrace && --nest == 0) {
-	    rbrace = p;
-	    break;
-	}
-	if (*p == '\\' && escape) {
-	    if (!*++p) break;
-	}
-	Inc(p, pend, enc);
+        if (*p == '{' && nest++ == 0) {
+            lbrace = p;
+        }
+        if (*p == '}' && lbrace && --nest == 0) {
+            rbrace = p;
+            break;
+        }
+        if (*p == '\\' && escape) {
+            if (!*++p) break;
+        }
+        Inc(p, pend, enc);
     }
 
     if (lbrace && rbrace) {
-	size_t len = strlen(s) + 1;
-	char *buf = GLOB_ALLOC_N(char, len);
-	long shift;
-
-	if (!buf) return -1;
-	memcpy(buf, s, lbrace-s);
-	shift = (lbrace-s);
-	p = lbrace;
-	while (p < rbrace) {
-	    const char *t = ++p;
-	    nest = 0;
-	    while (p < rbrace && !(*p == ',' && nest == 0)) {
-		if (*p == '{') nest++;
-		if (*p == '}') nest--;
-		if (*p == '\\' && escape) {
-		    if (++p == rbrace) break;
-		}
-		Inc(p, pend, enc);
-	    }
-	    memcpy(buf+shift, t, p-t);
-	    strlcpy(buf+shift+(p-t), rbrace+1, len-(shift+(p-t)));
-	    status = ruby_brace_expand(buf, flags, func, arg, enc, var);
-	    if (status) break;
-	}
-	GLOB_FREE(buf);
+        size_t len = strlen(s) + 1;
+        char *buf = GLOB_ALLOC_N(char, len);
+        long shift;
+
+        if (!buf) return -1;
+        memcpy(buf, s, lbrace-s);
+        shift = (lbrace-s);
+        p = lbrace;
+        while (p < rbrace) {
+            const char *t = ++p;
+            nest = 0;
+            while (p < rbrace && !(*p == ',' && nest == 0)) {
+                if (*p == '{') nest++;
+                if (*p == '}') nest--;
+                if (*p == '\\' && escape) {
+                    if (++p == rbrace) break;
+                }
+                Inc(p, pend, enc);
+            }
+            memcpy(buf+shift, t, p-t);
+            strlcpy(buf+shift+(p-t), rbrace+1, len-(shift+(p-t)));
+            status = ruby_brace_expand(buf, flags, func, arg, enc, var);
+            if (status) break;
+        }
+        GLOB_FREE(buf);
     }
     else if (!lbrace && !rbrace) {
-	status = glob_call_func(func, s, arg, enc);
+        status = glob_call_func(func, s, arg, enc);
     }
 
     RB_GC_GUARD(var);
@@ -2858,9 +2858,9 @@ push_glob(VALUE ary, VALUE str, VALUE base, int flags)
     str = rb_str_encode_ospath(str);
 #endif
     if (rb_enc_to_index(enc) == ENCINDEX_US_ASCII)
-	enc = rb_filesystem_encoding();
+        enc = rb_filesystem_encoding();
     if (rb_enc_to_index(enc) == ENCINDEX_US_ASCII)
-	enc = rb_ascii8bit_encoding();
+        enc = rb_ascii8bit_encoding();
     flags |= GLOB_VERBOSE;
     args.func = push_pattern;
     args.value = ary;
@@ -2868,23 +2868,23 @@ push_glob(VALUE ary, VALUE str, VALUE base, int flags)
     args.base = 0;
     fd = AT_FDCWD;
     if (!NIL_P(base)) {
-	if (!RB_TYPE_P(base, T_STRING) || !rb_enc_check(str, base)) {
-	    struct dir_data *dirp = DATA_PTR(base);
-	    if (!dirp->dir) dir_closed();
+        if (!RB_TYPE_P(base, T_STRING) || !rb_enc_check(str, base)) {
+            struct dir_data *dirp = DATA_PTR(base);
+            if (!dirp->dir) dir_closed();
 #ifdef HAVE_DIRFD
-	    if ((fd = dirfd(dirp->dir)) == -1)
-		rb_sys_fail_path(dir_inspect(base));
+            if ((fd = dirfd(dirp->dir)) == -1)
+                rb_sys_fail_path(dir_inspect(base));
 #endif
-	    base = dirp->path;
-	}
-	args.base = RSTRING_PTR(base);
+            base = dirp->path;
+        }
+        args.base = RSTRING_PTR(base);
     }
 #if defined _WIN32 || defined __APPLE__
     enc = rb_utf8_encoding();
 #endif
 
     return ruby_glob0(RSTRING_PTR(str), fd, args.base, flags, &rb_glob_funcs,
-		      (VALUE)&args, enc);
+                      (VALUE)&args, enc);
 }
 
 static VALUE
@@ -2895,13 +2895,13 @@ rb_push_glob(VALUE str, VALUE base, int flags) /* '\0' is delimiter */
 
     /* can contain null bytes as separators */
     if (!RB_TYPE_P(str, T_STRING)) {
-	FilePathValue(str);
+        FilePathValue(str);
     }
     else if (!rb_str_to_cstr(str)) {
         rb_raise(rb_eArgError, "nul-separated glob pattern is deprecated");
     }
     else {
-	rb_enc_check(str, rb_enc_from_encoding(rb_usascii_encoding()));
+        rb_enc_check(str, rb_enc_from_encoding(rb_usascii_encoding()));
     }
     ary = rb_ary_new();
 
@@ -2918,11 +2918,11 @@ dir_globs(VALUE args, VALUE base, int flags)
     long i;
 
     for (i = 0; i < RARRAY_LEN(args); ++i) {
-	int status;
-	VALUE str = RARRAY_AREF(args, i);
-	FilePathValue(str);
-	status = push_glob(ary, str, base, flags);
-	if (status) GLOB_JUMP_TAG(status);
+        int status;
+        VALUE str = RARRAY_AREF(args, i);
+        FilePathValue(str);
+        status = push_glob(ary, str, base, flags);
+        if (status) GLOB_JUMP_TAG(status);
     }
     RB_GC_GUARD(args);
 
@@ -2932,12 +2932,12 @@ dir_globs(VALUE args, VALUE base, int flags)
 static VALUE
 dir_glob_option_base(VALUE base)
 {
-    if (base == Qundef || NIL_P(base)) {
-	return Qnil;
+    if (NIL_OR_UNDEF_P(base)) {
+        return Qnil;
     }
 #if USE_OPENDIR_AT
     if (rb_typeddata_is_kind_of(base, &dir_data_type)) {
-	return base;
+        return base;
     }
 #endif
     FilePathValue(base);
@@ -2948,7 +2948,7 @@ dir_glob_option_base(VALUE base)
 static int
 dir_glob_option_sort(VALUE sort)
 {
-    return (rb_bool_expected(sort, "sort") ? 0 : FNM_GLOB_NOSORT);
+    return (rb_bool_expected(sort, "sort", TRUE) ? 0 : FNM_GLOB_NOSORT);
 }
 
 static VALUE
@@ -2957,7 +2957,7 @@ dir_s_aref(rb_execution_context_t *ec, VALUE obj, VALUE args, VALUE base, VALUE
     const int flags = dir_glob_option_sort(sort);
     base = dir_glob_option_base(base);
     if (RARRAY_LEN(args) == 1) {
-	return rb_push_glob(RARRAY_AREF(args, 0), base, flags);
+        return rb_push_glob(RARRAY_AREF(args, 0), base, flags);
     }
     return dir_globs(args, base, flags);
 }
@@ -2969,15 +2969,15 @@ dir_s_glob(rb_execution_context_t *ec, VALUE obj, VALUE str, VALUE rflags, VALUE
     const int flags = (NUM2INT(rflags) | dir_glob_option_sort(sort)) & ~FNM_CASEFOLD;
     base = dir_glob_option_base(base);
     if (NIL_P(ary)) {
-	ary = rb_push_glob(str, base, flags);
+        ary = rb_push_glob(str, base, flags);
     }
     else {
         ary = dir_globs(ary, base, flags);
     }
 
     if (rb_block_given_p()) {
-	rb_ary_each(ary);
-	return Qnil;
+        rb_ary_each(ary);
+        return Qnil;
     }
     return ary;
 }
@@ -3174,19 +3174,19 @@ fnmatch_brace(const char *pattern, VALUE val, void *enc)
     rb_encoding *enc_path = rb_enc_get(path);
 
     if (enc_pattern != enc_path) {
-	if (!rb_enc_asciicompat(enc_pattern))
-	    return FNM_NOMATCH;
-	if (!rb_enc_asciicompat(enc_path))
-	    return FNM_NOMATCH;
-	if (!rb_enc_str_asciionly_p(path)) {
-	    int cr = ENC_CODERANGE_7BIT;
-	    long len = strlen(pattern);
-	    if (rb_str_coderange_scan_restartable(pattern, pattern + len,
-						  enc_pattern, &cr) != len)
-		return FNM_NOMATCH;
-	    if (cr != ENC_CODERANGE_7BIT)
-		return FNM_NOMATCH;
-	}
+        if (!rb_enc_asciicompat(enc_pattern))
+            return FNM_NOMATCH;
+        if (!rb_enc_asciicompat(enc_path))
+            return FNM_NOMATCH;
+        if (!rb_enc_str_asciionly_p(path)) {
+            int cr = ENC_CODERANGE_7BIT;
+            long len = strlen(pattern);
+            if (rb_str_coderange_scan_restartable(pattern, pattern + len,
+                                                  enc_pattern, &cr) != len)
+                return FNM_NOMATCH;
+            if (cr != ENC_CODERANGE_7BIT)
+                return FNM_NOMATCH;
+        }
     }
     return (fnmatch(pattern, enc, RSTRING_PTR(path), arg->flags) == 0);
 }
@@ -3200,27 +3200,27 @@ file_s_fnmatch(int argc, VALUE *argv, VALUE obj)
     int flags;
 
     if (rb_scan_args(argc, argv, "21", &pattern, &path, &rflags) == 3)
-	flags = NUM2INT(rflags);
+        flags = NUM2INT(rflags);
     else
-	flags = 0;
+        flags = 0;
 
     StringValueCStr(pattern);
     FilePathStringValue(path);
 
     if (flags & FNM_EXTGLOB) {
-	struct brace_args args;
+        struct brace_args args;
 
-	args.value = path;
-	args.flags = flags;
-	if (ruby_brace_expand(RSTRING_PTR(pattern), flags, fnmatch_brace,
-			      (VALUE)&args, rb_enc_get(pattern), pattern) > 0)
-	    return Qtrue;
+        args.value = path;
+        args.flags = flags;
+        if (ruby_brace_expand(RSTRING_PTR(pattern), flags, fnmatch_brace,
+                              (VALUE)&args, rb_enc_get(pattern), pattern) > 0)
+            return Qtrue;
     }
     else {
-	rb_encoding *enc = rb_enc_compatible(pattern, path);
-	if (!enc) return Qfalse;
-	if (fnmatch(RSTRING_PTR(pattern), enc, RSTRING_PTR(path), flags) == 0)
-	    return Qtrue;
+        rb_encoding *enc = rb_enc_compatible(pattern, path);
+        if (!enc) return Qfalse;
+        if (fnmatch(RSTRING_PTR(pattern), enc, RSTRING_PTR(path), flags) == 0)
+            return Qtrue;
     }
     RB_GC_GUARD(pattern);
 
@@ -3244,12 +3244,12 @@ dir_s_home(int argc, VALUE *argv, VALUE obj)
     rb_check_arity(argc, 0, 1);
     user = (argc > 0) ? argv[0] : Qnil;
     if (!NIL_P(user)) {
-	SafeStringValue(user);
-	rb_must_asciicompat(user);
-	u = StringValueCStr(user);
-	if (*u) {
-	    return rb_home_dir_of(user, rb_str_new(0, 0));
-	}
+        SafeStringValue(user);
+        rb_must_asciicompat(user);
+        u = StringValueCStr(user);
+        if (*u) {
+            return rb_home_dir_of(user, rb_str_new(0, 0));
+        }
     }
     return rb_default_home_dir(rb_str_new(0, 0));
 
@@ -3279,24 +3279,24 @@ nogvl_dir_empty_p(void *ptr)
     VALUE result = Qtrue;
 
     if (!dir) {
-	int e = errno;
-	switch (gc_for_fd_with_gvl(e)) {
-	  default:
-	    dir = opendir(path);
-	    if (dir) break;
-	    e = errno;
-	    /* fall through */
-	  case 0:
-	    if (e == ENOTDIR) return (void *)Qfalse;
-	    errno = e; /* for rb_sys_fail_path */
-	    return (void *)Qundef;
-	}
+        int e = errno;
+        switch (gc_for_fd_with_gvl(e)) {
+          default:
+            dir = opendir(path);
+            if (dir) break;
+            e = errno;
+            /* fall through */
+          case 0:
+            if (e == ENOTDIR) return (void *)Qfalse;
+            errno = e; /* for rb_sys_fail_path */
+            return (void *)Qundef;
+        }
     }
     while ((dp = READDIR(dir, NULL)) != NULL) {
-	if (!to_be_skipped(dp)) {
-	    result = Qfalse;
-	    break;
-	}
+        if (!to_be_skipped(dp)) {
+            result = Qfalse;
+            break;
+        }
     }
     closedir(dir);
     return (void *)result;
@@ -3324,27 +3324,27 @@ rb_dir_s_empty_p(VALUE obj, VALUE dirname)
 
 #if defined HAVE_GETATTRLIST && defined ATTR_DIR_ENTRYCOUNT
     {
-	u_int32_t attrbuf[SIZEUP32(fsobj_tag_t)];
-	struct attrlist al = {ATTR_BIT_MAP_COUNT, 0, ATTR_CMN_OBJTAG,};
-	if (getattrlist(path, &al, attrbuf, sizeof(attrbuf), 0) != 0)
-	    rb_sys_fail_path(orig);
-	if (*(const fsobj_tag_t *)(attrbuf+1) == VT_HFS) {
-	    al.commonattr = 0;
-	    al.dirattr = ATTR_DIR_ENTRYCOUNT;
-	    if (getattrlist(path, &al, attrbuf, sizeof(attrbuf), 0) == 0) {
-		if (attrbuf[0] >= 2 * sizeof(u_int32_t))
-		    return RBOOL(attrbuf[1] == 0);
-		if (false_on_notdir) return Qfalse;
-	    }
-	    rb_sys_fail_path(orig);
-	}
+        u_int32_t attrbuf[SIZEUP32(fsobj_tag_t)];
+        struct attrlist al = {ATTR_BIT_MAP_COUNT, 0, ATTR_CMN_OBJTAG,};
+        if (getattrlist(path, &al, attrbuf, sizeof(attrbuf), 0) != 0)
+            rb_sys_fail_path(orig);
+        if (*(const fsobj_tag_t *)(attrbuf+1) == VT_HFS) {
+            al.commonattr = 0;
+            al.dirattr = ATTR_DIR_ENTRYCOUNT;
+            if (getattrlist(path, &al, attrbuf, sizeof(attrbuf), 0) == 0) {
+                if (attrbuf[0] >= 2 * sizeof(u_int32_t))
+                    return RBOOL(attrbuf[1] == 0);
+                if (false_on_notdir) return Qfalse;
+            }
+            rb_sys_fail_path(orig);
+        }
     }
 #endif
 
     result = (VALUE)rb_thread_call_without_gvl(nogvl_dir_empty_p, (void *)path,
-					    RUBY_UBF_IO, 0);
-    if (result == Qundef) {
-	rb_sys_fail_path(orig);
+                                            RUBY_UBF_IO, 0);
+    if (UNDEF_P(result)) {
+        rb_sys_fail_path(orig);
     }
     return result;
 }
diff --git a/dir.rb b/dir.rb
index d2ed92c287..2e426b0881 100644
--- a/dir.rb
+++ b/dir.rb
@@ -65,7 +65,7 @@
 #
 # - ::each_child: Calls the given block with each entry in the given directory,
 #   but not including <tt>.</tt> or <tt>..</tt>.
-# - ::foreach: Calls the given block with each entryin the given directory,
+# - ::foreach: Calls the given block with each entry in the given directory,
 #   including <tt>.</tt> and <tt>..</tt>.
 # - #each: Calls the given block with each entry in +self+,
 #   including <tt>.</tt> and <tt>..</tt>.
diff --git a/dln.c b/dln.c
index 6fa68289dd..0edd709bbe 100644
--- a/dln.c
+++ b/dln.c
@@ -41,6 +41,10 @@ static void dln_loaderror(const char *format, ...);
 # include <strings.h>
 #endif
 
+#if defined __APPLE__
+# include <AvailabilityMacros.h>
+#endif
+
 #ifndef xmalloc
 void *xmalloc();
 void *xcalloc();
@@ -58,7 +62,7 @@ void *xrealloc();
 #include <sys/stat.h>
 
 #ifndef S_ISDIR
-#   define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
+# define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
 #endif
 
 #ifdef HAVE_SYS_PARAM_H
@@ -110,8 +114,8 @@ init_funcname_len(const char **file)
 
     /* Load the file as an object one */
     for (base = p; *p; p++) { /* Find position of last '/' */
-	if (*p == '.' && !dot) dot = p;
-	if (isdirsep(*p)) base = p+1, dot = NULL;
+        if (*p == '.' && !dot) dot = p;
+        if (isdirsep(*p)) base = p+1, dot = NULL;
     }
     *file = base;
     /* Delete suffix if it exists */
@@ -126,7 +130,7 @@ static const char funcname_prefix[sizeof(FUNCNAME_PREFIX) - 1] = FUNCNAME_PREFIX
     const size_t plen = sizeof(funcname_prefix);\
     char *const tmp = ALLOCA_N(char, plen+flen+1);\
     if (!tmp) {\
-	dln_memerror();\
+        dln_memerror();\
     }\
     memcpy(tmp, funcname_prefix, plen);\
     memcpy(tmp+plen, base, flen);\
@@ -170,14 +174,14 @@ dln_strerror(char *message, size_t size)
     size_t len = snprintf(message, size, "%d: ", error);
 
 #define format_message(sublang) FormatMessage(\
-	FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,	\
-	NULL, error, MAKELANGID(LANG_NEUTRAL, (sublang)),		\
-	message + len, size - len, NULL)
+        FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,	\
+        NULL, error, MAKELANGID(LANG_NEUTRAL, (sublang)),		\
+        message + len, size - len, NULL)
     if (format_message(SUBLANG_ENGLISH_US) == 0)
-	format_message(SUBLANG_DEFAULT);
+        format_message(SUBLANG_DEFAULT);
     for (p = message + len; *p; p++) {
-	if (*p == '\n' || *p == '\r')
-	    *p = ' ';
+        if (*p == '\n' || *p == '\r')
+            *p = ' ';
     }
     return message;
 }
@@ -200,18 +204,18 @@ aix_loaderror(const char *pathname)
     snprintf(errbuf, sizeof(errbuf), "load failed - %s. ", pathname);
 
     if (loadquery(L_GETMESSAGES, &message[0], sizeof(message)) != -1) {
-	ERRBUF_APPEND("Please issue below command for detailed reasons:\n\t");
-	ERRBUF_APPEND("/usr/sbin/execerror ruby ");
-	for (i=0; message[i]; i++) {
-	    ERRBUF_APPEND("\"");
-	    ERRBUF_APPEND(message[i]);
-	    ERRBUF_APPEND("\" ");
-	}
-	ERRBUF_APPEND("\n");
+        ERRBUF_APPEND("Please issue below command for detailed reasons:\n\t");
+        ERRBUF_APPEND("/usr/sbin/execerror ruby ");
+        for (i=0; message[i]; i++) {
+            ERRBUF_APPEND("\"");
+            ERRBUF_APPEND(message[i]);
+            ERRBUF_APPEND("\" ");
+        }
+        ERRBUF_APPEND("\n");
     }
     else {
-	ERRBUF_APPEND(strerror(errno));
-	ERRBUF_APPEND("[loadquery failed]");
+        ERRBUF_APPEND(strerror(errno));
+        ERRBUF_APPEND("[loadquery failed]");
     }
     dln_loaderror("%s", errbuf);
 }
@@ -229,22 +233,22 @@ rb_w32_check_imported(HMODULE ext, HMODULE mine)
     desc = ImageDirectoryEntryToData(ext, TRUE, IMAGE_DIRECTORY_ENTRY_IMPORT, &size);
     if (!desc) return 0;
     while (desc->Name) {
-	PIMAGE_THUNK_DATA pint = (PIMAGE_THUNK_DATA)((char *)ext + desc->Characteristics);
-	PIMAGE_THUNK_DATA piat = (PIMAGE_THUNK_DATA)((char *)ext + desc->FirstThunk);
-	for (; piat->u1.Function; piat++, pint++) {
-	    static const char prefix[] = "rb_";
-	    PIMAGE_IMPORT_BY_NAME pii;
-	    const char *name;
-
-	    if (IMAGE_SNAP_BY_ORDINAL(pint->u1.Ordinal)) continue;
-	    pii = (PIMAGE_IMPORT_BY_NAME)((char *)ext + (size_t)pint->u1.AddressOfData);
-	    name = (const char *)pii->Name;
-	    if (strncmp(name, prefix, sizeof(prefix) - 1) == 0) {
-		FARPROC addr = GetProcAddress(mine, name);
-		if (addr) return (FARPROC)piat->u1.Function == addr;
-	    }
-	}
-	desc++;
+        PIMAGE_THUNK_DATA pint = (PIMAGE_THUNK_DATA)((char *)ext + desc->Characteristics);
+        PIMAGE_THUNK_DATA piat = (PIMAGE_THUNK_DATA)((char *)ext + desc->FirstThunk);
+        for (; piat->u1.Function; piat++, pint++) {
+            static const char prefix[] = "rb_";
+            PIMAGE_IMPORT_BY_NAME pii;
+            const char *name;
+
+            if (IMAGE_SNAP_BY_ORDINAL(pint->u1.Ordinal)) continue;
+            pii = (PIMAGE_IMPORT_BY_NAME)((char *)ext + (size_t)pint->u1.AddressOfData);
+            name = (const char *)pii->Name;
+            if (strncmp(name, prefix, sizeof(prefix) - 1) == 0) {
+                FARPROC addr = GetProcAddress(mine, name);
+                if (addr) return (FARPROC)piat->u1.Function == addr;
+            }
+        }
+        desc++;
     }
     return 1;
 }
@@ -252,11 +256,11 @@ rb_w32_check_imported(HMODULE ext, HMODULE mine)
 
 #if defined(DLN_NEEDS_ALT_SEPARATOR) && DLN_NEEDS_ALT_SEPARATOR
 #define translit_separator(src) do { \
-	char *tmp = ALLOCA_N(char, strlen(src) + 1), *p = tmp, c; \
-	do { \
-	    *p++ = ((c = *file++) == '/') ? DLN_NEEDS_ALT_SEPARATOR : c; \
-	} while (c); \
-	(src) = tmp; \
+        char *tmp = ALLOCA_N(char, strlen(src) + 1), *p = tmp, c; \
+        do { \
+            *p++ = ((c = *file++) == '/') ? DLN_NEEDS_ALT_SEPARATOR : c; \
+        } while (c); \
+        (src) = tmp; \
     } while (0)
 #else
 #define translit_separator(str) (void)(str)
@@ -273,7 +277,7 @@ dln_incompatible_func(void *handle, const char *funcname, void *const fp, const
     if (!ex) return false;
     if (ex == fp) return false;
     if (dladdr(ex, &dli)) {
-	*libname = dli.dli_fname;
+        *libname = dli.dli_fname;
     }
     return true;
 }
@@ -287,15 +291,28 @@ dln_incompatible_library_p(void *handle, const char **libname)
 {
 #define check_func(func) \
     if (dln_incompatible_func(handle, EXTERNAL_PREFIX #func, (void *)&func, libname)) \
-	return true
+        return true
     check_func(ruby_xmalloc);
     return false;
 }
 COMPILER_WARNING_POP
 #endif
 
-#if defined(MAC_OS_X_VERSION_MIN_REQUIRED) && \
-    (MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_11)
+#if !defined(MAC_OS_X_VERSION_MIN_REQUIRED)
+/* assume others than old Mac OS X have no problem */
+# define dln_disable_dlclose() false
+
+#elif !defined(MAC_OS_X_VERSION_10_11) || \
+    (MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_11)
+/* targeting older versions only */
+# define dln_disable_dlclose() true
+
+#elif MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_11
+/* targeting newer versions only */
+# define dln_disable_dlclose() false
+
+#else
+/* support both versions, and check at runtime */
 # include <sys/sysctl.h>
 
 static bool
@@ -308,8 +325,6 @@ dln_disable_dlclose(void)
     if (rev < MAC_OS_X_VERSION_10_11) return true;
     return false;
 }
-#else
-# define dln_disable_dlclose() false
 #endif
 
 #if defined(_WIN32) || defined(USE_DLN_DLOPEN)
@@ -326,7 +341,7 @@ dln_open(const char *file)
     /* Convert the file path to wide char */
     WCHAR *winfile = rb_w32_mbstr_to_wstr(CP_UTF8, file, -1, NULL);
     if (!winfile) {
-	dln_memerror();
+        dln_memerror();
     }
 
     /* Load file */
@@ -334,15 +349,15 @@ dln_open(const char *file)
     free(winfile);
 
     if (!handle) {
-	error = dln_strerror();
-	goto failed;
+        error = dln_strerror();
+        goto failed;
     }
 
 # if defined(RUBY_EXPORT)
     if (!rb_w32_check_imported(handle, rb_libruby_handle())) {
-	FreeLibrary(handle);
-	error = incompatible;
-	goto failed;
+        FreeLibrary(handle);
+        error = incompatible;
+        goto failed;
     }
 # endif
 
@@ -367,24 +382,24 @@ dln_open(const char *file)
 
 # if defined(RUBY_EXPORT)
     {
-	const char *libruby_name = NULL;
-	if (dln_incompatible_library_p(handle, &libruby_name)) {
-	    if (dln_disable_dlclose()) {
-		/* dlclose() segfaults */
-		if (libruby_name) {
-		    dln_fatalerror("linked to incompatible %s - %s", libruby_name, file);
-		}
-		dln_fatalerror("%s - %s", incompatible, file);
-	    }
-	    else {
-		dlclose(handle);
-		if (libruby_name) {
-		    dln_loaderror("linked to incompatible %s - %s", libruby_name, file);
-		}
-		error = incompatible;
-		goto failed;
-	    }
-	}
+        const char *libruby_name = NULL;
+        if (dln_incompatible_library_p(handle, &libruby_name)) {
+            if (dln_disable_dlclose()) {
+                /* dlclose() segfaults */
+                if (libruby_name) {
+                    dln_fatalerror("linked to incompatible %s - %s", libruby_name, file);
+                }
+                dln_fatalerror("%s - %s", incompatible, file);
+            }
+            else {
+                dlclose(handle);
+                if (libruby_name) {
+                    dln_loaderror("linked to incompatible %s - %s", libruby_name, file);
+                }
+                error = incompatible;
+                goto failed;
+            }
+        }
     }
 # endif
 #endif
@@ -445,7 +460,7 @@ dln_load(const char *file)
     unsigned long long (*abi_version_fct)(void) = (unsigned long long(*)(void))dln_sym(handle, "ruby_abi_version");
     unsigned long long binary_abi_version = (*abi_version_fct)();
     if (binary_abi_version != ruby_abi_version() && abi_check_enabled_p()) {
-        dln_loaderror("ABI version of binary is incompatible with this Ruby. Try rebuilding this binary.");
+        dln_loaderror("incompatible ABI version of binary - %s", file);
     }
 #endif
 
@@ -460,17 +475,17 @@ dln_load(const char *file)
 
 #elif defined(_AIX)
     {
-	void (*init_fct)(void);
-
-	init_fct = (void(*)(void))load((char*)file, 1, 0);
-	if (init_fct == NULL) {
-	    aix_loaderror(file);
-	}
-	if (loadbind(0, (void*)dln_load, (void*)init_fct) == -1) {
-	    aix_loaderror(file);
-	}
-	(*init_fct)();
-	return (void*)init_fct;
+        void (*init_fct)(void);
+
+        init_fct = (void(*)(void))load((char*)file, 1, 0);
+        if (init_fct == NULL) {
+            aix_loaderror(file);
+        }
+        if (loadbind(0, (void*)dln_load, (void*)init_fct) == -1) {
+            aix_loaderror(file);
+        }
+        (*init_fct)();
+        return (void*)init_fct;
     }
 #else
     dln_notimplement();
diff --git a/dln_find.c b/dln_find.c
index 96e06d34c4..5d380f5d39 100644
--- a/dln_find.c
+++ b/dln_find.c
@@ -53,26 +53,26 @@ char *getenv();
 #endif
 
 static char *dln_find_1(const char *fname, const char *path, char *buf, size_t size, int exe_flag
-			DLN_FIND_EXTRA_ARG_DECL);
+                        DLN_FIND_EXTRA_ARG_DECL);
 
 char *
 dln_find_exe_r(const char *fname, const char *path, char *buf, size_t size
-	       DLN_FIND_EXTRA_ARG_DECL)
+               DLN_FIND_EXTRA_ARG_DECL)
 {
     char *envpath = 0;
 
     if (!path) {
-	path = getenv(PATH_ENV);
-	if (path) path = envpath = strdup(path);
+        path = getenv(PATH_ENV);
+        if (path) path = envpath = strdup(path);
     }
 
     if (!path) {
-	path =
-	    "/usr/local/bin" PATH_SEP
-	    "/usr/ucb" PATH_SEP
-	    "/usr/bin" PATH_SEP
-	    "/bin" PATH_SEP
-	    ".";
+        path =
+            "/usr/local/bin" PATH_SEP
+            "/usr/ucb" PATH_SEP
+            "/usr/bin" PATH_SEP
+            "/bin" PATH_SEP
+            ".";
     }
     buf = dln_find_1(fname, path, buf, size, 1 DLN_FIND_EXTRA_ARG);
     if (envpath) free(envpath);
@@ -81,7 +81,7 @@ dln_find_exe_r(const char *fname, const char *path, char *buf, size_t size
 
 char *
 dln_find_file_r(const char *fname, const char *path, char *buf, size_t size
-		DLN_FIND_EXTRA_ARG_DECL)
+                DLN_FIND_EXTRA_ARG_DECL)
 {
     if (!path) path = ".";
     return dln_find_1(fname, path, buf, size, 0 DLN_FIND_EXTRA_ARG);
@@ -89,8 +89,8 @@ dln_find_file_r(const char *fname, const char *path, char *buf, size_t size
 
 static char *
 dln_find_1(const char *fname, const char *path, char *fbuf, size_t size,
-	   int exe_flag /* non 0 if looking for executable. */
-	   DLN_FIND_EXTRA_ARG_DECL)
+           int exe_flag /* non 0 if looking for executable. */
+           DLN_FIND_EXTRA_ARG_DECL)
 {
     register const char *dp;
     register const char *ep;
@@ -99,7 +99,7 @@ dln_find_1(const char *fname, const char *path, char *fbuf, size_t size,
     size_t i, fnlen, fspace;
 #ifdef DOSISH
     static const char extension[][5] = {
-	EXECUTABLE_EXTS,
+        EXECUTABLE_EXTS,
     };
     size_t j;
     int is_abs = 0, has_path = 0;
@@ -110,21 +110,21 @@ dln_find_1(const char *fname, const char *path, char *fbuf, size_t size,
     static const char pathname_too_long[] = "openpath: pathname too long (ignored)\n\
 \tDirectory \"%.*s\"%s\n\tFile \"%.*s\"%s\n";
 #define PATHNAME_TOO_LONG() dln_warning(dln_warning_arg pathname_too_long, \
-					((bp - fbuf) > 100 ? 100 : (int)(bp - fbuf)), fbuf, \
-					((bp - fbuf) > 100 ? "..." : ""), \
-					(fnlen > 100 ? 100 : (int)fnlen), fname, \
-					(fnlen > 100 ? "..." : ""))
+                                        ((bp - fbuf) > 100 ? 100 : (int)(bp - fbuf)), fbuf, \
+                                        ((bp - fbuf) > 100 ? "..." : ""), \
+                                        (fnlen > 100 ? 100 : (int)fnlen), fname, \
+                                        (fnlen > 100 ? "..." : ""))
 
 #define RETURN_IF(expr) if (expr) return (char *)fname;
 
     RETURN_IF(!fname);
     fnlen = strlen(fname);
     if (fnlen >= size) {
-	dln_warning(dln_warning_arg
-		    "openpath: pathname too long (ignored)\n\tFile \"%.*s\"%s\n",
-		    (fnlen > 100 ? 100 : (int)fnlen), fname,
-		    (fnlen > 100 ? "..." : ""));
-	return NULL;
+        dln_warning(dln_warning_arg
+                    "openpath: pathname too long (ignored)\n\tFile \"%.*s\"%s\n",
+                    (fnlen > 100 ? 100 : (int)fnlen), fname,
+                    (fnlen > 100 ? "..." : ""));
+        return NULL;
     }
 #ifdef DOSISH
 # ifndef CharNext
@@ -132,52 +132,52 @@ dln_find_1(const char *fname, const char *path, char *fbuf, size_t size,
 # endif
 # ifdef DOSISH_DRIVE_LETTER
     if (((p[0] | 0x20) - 'a') < 26  && p[1] == ':') {
-	p += 2;
-	is_abs = 1;
+        p += 2;
+        is_abs = 1;
     }
 # endif
     switch (*p) {
       case '/': case '\\':
-	is_abs = 1;
-	p++;
+        is_abs = 1;
+        p++;
     }
     has_path = is_abs;
     while (*p) {
-	switch (*p) {
-	  case '/': case '\\':
-	    has_path = 1;
-	    ext = 0;
-	    p++;
-	    break;
-	  case '.':
-	    ext = p;
-	    p++;
-	    break;
-	  default:
-	    p = CharNext(p);
-	}
+        switch (*p) {
+          case '/': case '\\':
+            has_path = 1;
+            ext = 0;
+            p++;
+            break;
+          case '.':
+            ext = p;
+            p++;
+            break;
+          default:
+            p = CharNext(p);
+        }
     }
     if (ext) {
-	for (j = 0; STRCASECMP(ext, extension[j]); ) {
-	    if (++j == sizeof(extension) / sizeof(extension[0])) {
-		ext = 0;
-		break;
-	    }
-	}
+        for (j = 0; STRCASECMP(ext, extension[j]); ) {
+            if (++j == sizeof(extension) / sizeof(extension[0])) {
+                ext = 0;
+                break;
+            }
+        }
     }
     ep = bp = 0;
     if (!exe_flag) {
-	RETURN_IF(is_abs);
+        RETURN_IF(is_abs);
     }
     else if (has_path) {
-	RETURN_IF(ext);
-	i = p - fname;
-	if (i + 1 > size) goto toolong;
-	fspace = size - i - 1;
-	bp = fbuf;
-	ep = p;
-	memcpy(fbuf, fname, i + 1);
-	goto needs_extension;
+        RETURN_IF(ext);
+        i = p - fname;
+        if (i + 1 > size) goto toolong;
+        fspace = size - i - 1;
+        bp = fbuf;
+        ep = p;
+        memcpy(fbuf, fname, i + 1);
+        goto needs_extension;
     }
     p = fname;
 #endif
@@ -189,85 +189,85 @@ dln_find_1(const char *fname, const char *path, char *fbuf, size_t size,
 #undef RETURN_IF
 
     for (dp = path;; dp = ++ep) {
-	register size_t l;
-
-	/* extract a component */
-	ep = strchr(dp, PATH_SEP[0]);
-	if (ep == NULL)
-	    ep = dp+strlen(dp);
-
-	/* find the length of that component */
-	l = ep - dp;
-	bp = fbuf;
-	fspace = size - 2;
-	if (l > 0) {
-	    /*
-	    **	If the length of the component is zero length,
-	    **	start from the current directory.  If the
-	    **	component begins with "~", start from the
-	    **	user's $HOME environment variable.  Otherwise
-	    **	take the path literally.
-	    */
-
-	    if (*dp == '~' && (l == 1 ||
+        register size_t l;
+
+        /* extract a component */
+        ep = strchr(dp, PATH_SEP[0]);
+        if (ep == NULL)
+            ep = dp+strlen(dp);
+
+        /* find the length of that component */
+        l = ep - dp;
+        bp = fbuf;
+        fspace = size - 2;
+        if (l > 0) {
+            /*
+            **	If the length of the component is zero length,
+            **	start from the current directory.  If the
+            **	component begins with "~", start from the
+            **	user's $HOME environment variable.  Otherwise
+            **	take the path literally.
+            */
+
+            if (*dp == '~' && (l == 1 ||
 #if defined(DOSISH)
-			       dp[1] == '\\' ||
+                               dp[1] == '\\' ||
 #endif
-			       dp[1] == '/')) {
-		const char *home;
-
-		home = getenv("HOME");
-		if (home != NULL) {
-		    i = strlen(home);
-		    if (fspace < i)
-			goto toolong;
-		    fspace -= i;
-		    memcpy(bp, home, i);
-		    bp += i;
-		}
-		dp++;
-		l--;
-	    }
-	    if (l > 0) {
-		if (fspace < l)
-		    goto toolong;
-		fspace -= l;
-		memcpy(bp, dp, l);
-		bp += l;
-	    }
-
-	    /* add a "/" between directory and filename */
-	    if (ep[-1] != '/')
-		*bp++ = '/';
-	}
-
-	/* now append the file name */
-	i = fnlen;
-	if (fspace < i) {
+                               dp[1] == '/')) {
+                const char *home;
+
+                home = getenv("HOME");
+                if (home != NULL) {
+                    i = strlen(home);
+                    if (fspace < i)
+                        goto toolong;
+                    fspace -= i;
+                    memcpy(bp, home, i);
+                    bp += i;
+                }
+                dp++;
+                l--;
+            }
+            if (l > 0) {
+                if (fspace < l)
+                    goto toolong;
+                fspace -= l;
+                memcpy(bp, dp, l);
+                bp += l;
+            }
+
+            /* add a "/" between directory and filename */
+            if (ep[-1] != '/')
+                *bp++ = '/';
+        }
+
+        /* now append the file name */
+        i = fnlen;
+        if (fspace < i) {
             goto toolong;
-	}
-	fspace -= i;
-	memcpy(bp, fname, i + 1);
+        }
+        fspace -= i;
+        memcpy(bp, fname, i + 1);
 
 #if defined(DOSISH)
-	if (exe_flag && !ext) {
+        if (exe_flag && !ext) {
             goto needs_extension;
-	}
+        }
 #endif
 
 #ifndef S_ISREG
 # define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)
 #endif
-	if (stat(fbuf, &st) == 0 && S_ISREG(st.st_mode)) {
-	    if (exe_flag == 0) return fbuf;
-	    /* looking for executable */
-	    if (eaccess(fbuf, X_OK) == 0) return fbuf;
-	}
+        if (stat(fbuf, &st) == 0 && S_ISREG(st.st_mode)) {
+            if (exe_flag == 0) return fbuf;
+            /* looking for executable */
+            if (eaccess(fbuf, X_OK) == 0) return fbuf;
+        }
       next:
-	/* if not, and no other alternatives, life is bleak */
-	if (*ep == '\0') {
-	    return NULL;
-	}
+        /* if not, and no other alternatives, life is bleak */
+        if (*ep == '\0') {
+            return NULL;
+        }
         continue;
 
       toolong:
@@ -287,6 +287,6 @@ dln_find_1(const char *fname, const char *path, char *fbuf, size_t size,
         }
         goto next;
 #endif
-	/* otherwise try the next component in the search path */
+        /* otherwise try the next component in the search path */
     }
 }
diff --git a/dmyenc.c b/dmyenc.c
index 7e006e826c..75b8a2da43 100644
--- a/dmyenc.c
+++ b/dmyenc.c
@@ -5,6 +5,6 @@ void
 Init_enc(void)
 {
     if (require("enc/encdb.so") == 1) {
-	require("enc/trans/transdb.so");
+        require("enc/trans/transdb.so");
     }
 }
diff --git a/doc/.document b/doc/.document
index 84c1be6e5e..f589dda07c 100644
--- a/doc/.document
+++ b/doc/.document
@@ -1,6 +1,9 @@
 *.md
 *.rb
 *.rdoc
+contributing
 NEWS
 syntax
 optparse
+rdoc
+yjit
diff --git a/doc/ChangeLog-0.60_to_1.1 b/doc/ChangeLog-0.60_to_1.1
index ff3c376f4d..59d195e780 100644
--- a/doc/ChangeLog-0.60_to_1.1
+++ b/doc/ChangeLog-0.60_to_1.1
@@ -3573,7 +3573,7 @@ Fri Mar 17 15:56:44 1995  Yukihiro Matsumoto  (matz@ix-02)
 	* dln.c: dlopen��るマシン����らを使�よ��．���，�ゃん
 	  �動���る�����自信���．
 
-	* regex.c: virtual concatinationをや��．
+	* regex.c: virtual concatenationをや��．
 
 Thu Mar 16 11:32:57 1995  Yukihiro Matsumoto  (matz@ix-02)
 
diff --git a/doc/ChangeLog-1.9.3 b/doc/ChangeLog-1.9.3
index 58e3b6f67d..0f80eed2d5 100644
--- a/doc/ChangeLog-1.9.3
+++ b/doc/ChangeLog-1.9.3
@@ -23228,7 +23228,7 @@ Fri Sep 11 10:38:33 2009  URABE Shyouhei  <shyouhei@ruby-lang.org>
 
 	* lib/net/http.rb (Net::HTTPHeader::encode_kvpair): also call to_s
 	  to k.  A patch from swdyh <youhei@gmail.com>
-	  http://github.com/swdyh/ruby/tree/c847f43c2ccb679b9ff728f8b1b16c6ceeb57f39
+	  https://github.com/swdyh/ruby/tree/c847f43c2ccb679b9ff728f8b1b16c6ceeb57f39
 
 Fri Sep 11 09:45:11 2009  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
diff --git a/doc/ChangeLog-2.0.0 b/doc/ChangeLog-2.0.0
index b51d742203..9e654db189 100644
--- a/doc/ChangeLog-2.0.0
+++ b/doc/ChangeLog-2.0.0
@@ -16451,7 +16451,7 @@ Mon Mar  5 17:11:44 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 	  Exception#initialize doesn't use visible instance variable for
 	  the exception message, so call the method with the message.
 	  patched by Jingwen Owen Ou <jingweno AT gmail.com>.
-	  http://github.com/ruby/ruby/pull/41
+	  https://github.com/ruby/ruby/pull/41
 
 Mon Mar  5 16:50:22 2012  NAKAMURA Usaku  <usa@ruby-lang.org>
 
@@ -16858,13 +16858,13 @@ Fri Feb 24 13:54:33 2012  Aaron Patterson <aaron@tenderlovemaking.com>
 Fri Feb 24 12:07:34 2012  Ayumu AIZAWA  <ayumu.aizawa@gmail.com>
 
 	* lib/net/http.rb: Fix documentation. Patched from Florian Mhun
-	  via http://github.com/ruby/ruby/pull/96
+	  via https://github.com/ruby/ruby/pull/96
 
 Fri Feb 24 11:48:07 2012  Ayumu AIZAWA  <ayumu.aizawa@gmail.com>
 
 	* string.c (rb_str_prepend): Fix documentation for String#prepend.
-	  Patched from Franck Verrot via http://github.com/ruby/ruby/pull/98
-	  and Andrew Horsman via http://github.com/ruby/ruby/pull/55
+	  Patched from Franck Verrot via https://github.com/ruby/ruby/pull/98
+	  and Andrew Horsman via https://github.com/ruby/ruby/pull/55
 
 Fri Feb 24 10:08:33 2012  Eric Hodel  <drbrain@segment7.net>
 
diff --git a/doc/ChangeLog-2.3.0 b/doc/ChangeLog-2.3.0
index 7f3c4e672a..94996cffd0 100644
--- a/doc/ChangeLog-2.3.0
+++ b/doc/ChangeLog-2.3.0
@@ -170,7 +170,7 @@ Tue Dec 22 14:31:28 2015  Toru Iwase  <tietew@tietew.net>
 	  should return unfrozen new string.
 	  [ruby-core:72426] [Bug #11858]
 
-Tue Dec 22 05:39:58 2015  Takashi Kokubun  <takashikkbn@gmail.com>
+Tue Dec 22 05:39:58 2015  Takashi Kokubun  <k0kubun@ruby-lang.org>
 
 	* ext/cgi/escape/escape.c (preserve_original_state): Preserve
 	  original state for tainted and frozen.  [Fix GH-1166]
@@ -208,7 +208,7 @@ Mon Dec 21 09:33:17 2015  Karol Bucek  <kares@users.noreply.github.com>
 	* ext/openssl/lib/openssl/ssl.rb (OpenSSL::SSL::SSLSocket): fix
 	  NotImplementedError typo.  [Fix GH-1165]
 
-Sun Dec 20 20:54:51 2015  Takashi Kokubun  <takashikkbn@gmail.com>
+Sun Dec 20 20:54:51 2015  Takashi Kokubun  <k0kubun@ruby-lang.org>
 
 	* cgi/escape/escape.c: Optimize CGI.escapeHTML for
 	  ASCII-compatible encodings.  [Fix GH-1164]
@@ -476,7 +476,7 @@ Tue Dec 15 17:57:57 2015  Martin Duerst  <duerst@it.aoyama.ac.jp>
 	  to the correct one in the IANA registry (IBM037)
 	  and added an alias (ebcdic-cp-us)
 
-Tue Dec 15 16:19:26 2015  Takashi Kokubun  <takashikkbn@gmail.com>
+Tue Dec 15 16:19:26 2015  Takashi Kokubun  <k0kubun@ruby-lang.org>
 
 	* lib/erb.rb: Render erb with array buffer for function call optimization.
 	  [fix GH-1143]
@@ -488,7 +488,7 @@ Tue Dec 15 13:50:05 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 	* string.c (rb_str_oct): [DOC] mention radix indicators.
 	  [ruby-core:71310] [Bug #11648]
 
-Tue Dec 15 12:20:30 2015  Takashi Kokubun  <takashikkbn@gmail.com>
+Tue Dec 15 12:20:30 2015  Takashi Kokubun  <k0kubun@ruby-lang.org>
 
 	* lib/erb.rb: Simplify regexp to optimize erb scanner.
 	  [fix GH-1144]
@@ -2670,7 +2670,7 @@ Sat Nov  7 09:51:38 2015  Koichi Sasada  <ko1@atdot.net>
 	* vm_trace.c (rb_threadptr_exec_event_hooks_orig):
 	  maintain trace_running counter on internal events.
 
-	  This patch is made by Takashi Kokubun <takashikkbn@gmail.com>.
+	  This patch is made by Takashi Kokubun <k0kubun@ruby-lang.org>.
 	  [Bug #11603] https://github.com/ruby/ruby/pull/1059
 
 Sat Nov  7 03:32:27 2015  Koichi Sasada  <ko1@atdot.net>
@@ -5283,7 +5283,7 @@ Sat Aug  1 06:54:36 2015  Aaron Patterson <tenderlove@ruby-lang.org>
 
 	* ext/openssl/ossl_ssl.c (Init_ossl_ssl): OpenSSL declares these
 	  constants as longs, so we should follow that and use LONG2NUM.
-	  http://git.io/vOqxD
+	  https://github.com/openssl/openssl/blob/34750dc25d74e3db4c1ba43cd219d3f4825e4c65/include/openssl/ssl.h#L391
 
 Sat Aug  1 04:06:29 2015  Aaron Patterson <tenderlove@ruby-lang.org>
 
@@ -6754,7 +6754,8 @@ Thu Jul  2 09:51:44 2015  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
 Thu Jul  2 06:49:44 2015  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
 
 	* lib/rubygems: Update to RubyGems HEAD(c202db2).
-	  this version contains many enhancements see http://git.io/vtNwF
+	  this version contains many enhancements see
+	  https://github.com/rubygems/rubygems/blob/c202db2d681eb3c3a02f187d346fbb2e8d733b26/History.txt#L3
 	* test/rubygems: ditto.
 
 Wed Jul  1 23:50:34 2015  Kazuhiro NISHIYAMA  <zn@mbf.nifty.com>
diff --git a/doc/NEWS/NEWS-3.0.0.md b/doc/NEWS/NEWS-3.0.0.md
index 00c26fe585..bdbd47327b 100644
--- a/doc/NEWS/NEWS-3.0.0.md
+++ b/doc/NEWS/NEWS-3.0.0.md
@@ -512,6 +512,18 @@ Outstanding ones only.
 
     * This version is Ractor compatible.
 
+* URI
+
+    * URI.escape and URI.unescape have been removed.
+      Instead, use the following methods depending on your specific use case.
+
+        * CGI.escape
+        * URI.encode_www_form
+        * URI.encode_www_form_component
+        * CGI.unescape
+        * URI.decode_www_form
+        * URI.decode_www_form_component
+
 ## Compatibility issues
 
 Excluding feature bug fixes.
diff --git a/doc/case_mapping.rdoc b/doc/case_mapping.rdoc
index 29d7bc6c33..3c42154973 100644
--- a/doc/case_mapping.rdoc
+++ b/doc/case_mapping.rdoc
@@ -28,13 +28,13 @@ In Symbol:
 
 By default, all of these methods use full Unicode case mapping,
 which is suitable for most languages.
-See {Unicode Latin Case Chart}[https://www.unicode.org/charts/case].
+See {Section 3.13 (Default Case Algorithms) of the Unicode standard}[https://www.unicode.org/versions/latest/ch03.pdf].
 
 Non-ASCII case mapping and folding are supported for UTF-8,
 UTF-16BE/LE, UTF-32BE/LE, and ISO-8859-1~16 Strings/Symbols.
 
 Context-dependent case mapping as described in
-{Table 3-17 of the Unicode standard}[https://www.unicode.org/versions/Unicode13.0.0/ch03.pdf]
+{Table 3-17 (Context Specification for Casing) of the Unicode standard}[https://www.unicode.org/versions/latest/ch03.pdf]
 is currently not supported.
 
 In most cases, case conversions of a string have the same number of characters.
diff --git a/doc/command_injection.rdoc b/doc/command_injection.rdoc
index 8f1303bcf7..af09be23f0 100644
--- a/doc/command_injection.rdoc
+++ b/doc/command_injection.rdoc
@@ -8,7 +8,7 @@ They should not be called with unknown or unsanitized commands.
 These methods include:
 
 - Kernel.system
-- {`command` (backtick method)}[rdoc-ref:Kernel#`]
+- {\`command` (backtick method)}[rdoc-ref:Kernel#`]
   (also called by the expression <tt>%x[command]</tt>).
 - IO.popen(command).
 - IO.read(command).
diff --git a/doc/contributing.md b/doc/contributing.md
new file mode 100644
index 0000000000..a6c63de9b2
--- /dev/null
+++ b/doc/contributing.md
@@ -0,0 +1,12 @@
+# Contributing to Ruby
+
+This guide outlines ways to get started with contributing to Ruby:
+
+* [Reporting issues](contributing/reporting_issues.md): How to report issues, how to request features, and how backporting works
+* [Building Ruby](contributing/building_ruby.md): How to build Ruby on your local machine for development
+* [Testing Ruby](contributing/testing_ruby.md): How to test Ruby on your local machine once you've built it
+* [Making changes to Ruby](contributing/making_changes_to_ruby.md): How to submit pull requests
+  to change Ruby's documentation, code, test suite, or standard libraries
+* [Making changes to Ruby standard libraries](contributing/making_changes_to_stdlibs.md): How to build, test, and contribute to Ruby standard libraries
+* [Making changes to Ruby documentation](contributing/documentation_guide.md): How to make changes to Ruby documentation
+* [Benchmarking Ruby](https://github.com/ruby/ruby/tree/master/benchmark#make-benchmark): How to benchmark Ruby
diff --git a/doc/contributing.rdoc b/doc/contributing.rdoc
deleted file mode 100644
index 00875d1428..0000000000
--- a/doc/contributing.rdoc
+++ /dev/null
@@ -1,402 +0,0 @@
-= Contributing to Ruby
-
-Ruby has a vast and friendly community with hundreds of people contributing to
-a thriving open-source ecosystem. This guide is designed to cover ways for
-participating in the development of CRuby.
-
-There are plenty of ways for you to help even if you're not ready to write
-code or documentation.  You can help by reporting issues, testing patches, and
-trying out beta releases with your applications.
-
-== How To Report
-
-If you've encountered a bug in Ruby please report it to the redmine issue
-tracker available at {bugs.ruby-lang.org}[https://bugs.ruby-lang.org/].  Do not
-report security vulnerabilities here, there is a {separate
-channel}[rdoc-label:label-Reporting+Security+Issues] for them.
-
-There are a few simple steps you should follow in order to receive feedback
-on your ticket.
-
-* If you haven't already,
-  {sign up for an account}[https://bugs.ruby-lang.org/account/register] on the
-  bug tracker.
-* Try the latest version.
-
-  If you aren't already using the latest version, try installing a newer
-  stable release. See
-  {Downloading Ruby}[https://www.ruby-lang.org/en/downloads/].
-* Look to see if anyone already reported your issue, try
-  {searching on redmine}[https://bugs.ruby-lang.org/projects/ruby-master/issues]
-  for your problem.
-* If you can't find a ticket addressing your issue,
-  {create a new one}[https://bugs.ruby-lang.org/projects/ruby-master/issues/new].
-* Choose the target version, usually current. Bugs will be first fixed in the
-  current release and then {backported}[rdoc-label:label-Backport+Requests].
-* Fill in the Ruby version you're using when experiencing this issue
-  (<code>ruby -v</code>).
-* Attach any logs or reproducible programs to provide additional information.
-  Reproducible scripts should be as small as possible.
-* Briefly describe your problem.  A 2-3 sentence description will help give a
-  quick response.
-* Pick a category, such as core for common problems, or lib for a standard
-  library.
-* Check the {Maintainers
-  list}[https://bugs.ruby-lang.org/projects/ruby/wiki/Maintainers] and assign
-  the ticket if there is an active maintainer for the library or feature.
-* If the ticket doesn't have any replies after 10 days, you can send a
-  reminder.
-* Please reply to feedback requests. If a bug report doesn't get any feedback,
-  it'll eventually get rejected.
-
-=== Reporting to downstream distributions
-
-You can report downstream issues for the following distributions via their bug tracker:
-
-* {debian}[https://bugs.debian.org/cgi-bin/pkgreport.cgi?src=ruby-defaults]
-* {freebsd}[http://www.freebsd.org/cgi/query-pr-summary.cgi?text=ruby]
-* {redhat}[https://bugzilla.redhat.com/buglist.cgi?bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&bug_status=MODIFIED]
-* {macports}[https://trac.macports.org/query?status=assigned&status=new&status=reopened&port=~ruby]
-* etc (add your distribution bug tracker here)
-
-== Reporting Security Issues
-
-Security vulnerabilities receive special treatment since they may negatively
-affect many users. There is a private mailing list that all security issues
-should be reported to and will be handled discretely. Email the
-mailto:security@ruby-lang.org list and the problem will be published after
-fixes have been released. You can also encrypt the issue using {the PGP public
-key}[https://www.ruby-lang.org/security.asc] for the list.
-
-== Reporting Other Issues
-
-If you're having an issue with the website, or maybe the mailing list, you can
-contact the webmaster to help resolve the problem.
-
-The current webmaster is:
-
-* Hiroshi SHIBATA (hsbt)
-
-You can also report issues with the ruby-lang.org website on the issue tracker:
-
-* {issue tracker}[https://github.com/ruby/www.ruby-lang.org/issues]
-
-== Resolve Existing Issues
-
-As a next step beyond reporting issues you can help the core team resolve
-existing issues. If you check the Everyone's Issues list in GitHub Issues,
-you will find a lot of issues already requiring attention. What can you do for
-these? Quite a bit, actually:
-
-When a bug report goes for a while without any feedback, it goes to the bug
-graveyard which is unfortunate. If you check the {issues
-list}[https://bugs.ruby-lang.org/projects/ruby-master/issues] you will find lots
-of delinquent bugs that require attention.
-
-You can help by verifying the existing tickets, try to reproduce the reported
-issue on your own and comment if you still experience the bug. Some issues
-lack attention because of too much ambiguity, to help you can narrow down the
-problem and provide more specific details or instructions to reproduce the
-bug. You might also try contributing a failing test in the form of a patch,
-which we will cover later in this guide.
-
-It may also help to try out patches other contributors have submitted to
-redmine, if gone without notice. In this case the +patch+ command is your
-friend, see <code>man patch</code> for more information. Basically this would
-go something like this:
-
-  cd path/to/ruby
-  patch -p0 < path/to/patch
-
-You will then be prompted to apply the patch with the associated files. After
-building ruby again, you should try to run the tests and verify if the change
-actually worked or fixed the bug. It's important to provide valuable feedback
-on the patch that can help reach the overall goal, try to answer some of these
-questions:
-
-* What do you like about this change?
-* What would you do differently?
-* Are there any other edge cases not tested?
-* Is there any documentation that would be affected by this change?
-
-If you can answer some or all of these questions, you're on the right track.
-If your comment simply says "+1", then odds are that other reviewers aren't
-going to take it too seriously. Show that you took the time to review the
-patch.
-
-== How To Request Features
-
-If there's a new feature that you want to see added to Ruby, you will need to
-write a convincing proposal and patch to implement the feature.
-
-For new features in CRuby, use the {'Feature'
-tracker}[https://bugs.ruby-lang.org/projects/ruby-master/issues?set_filter=1&tracker_id=2]
-on ruby-master. For non-CRuby dependent features, features that would apply to
-alternate Ruby implementations such as JRuby and Rubinius, use the {CommonRuby
-tracker}[https://bugs.ruby-lang.org/projects/common-ruby].
-
-When writing a proposal be sure to check for previous discussions on the
-topic and have a solid use case. You will need to be persuasive and convince
-Matz on your new feature. You should also consider the potential compatibility
-issues that this new feature might raise.
-
-Consider making your feature into a gem, and if there are enough people who
-benefit from your feature it could help persuade ruby-core. Although feature
-requests can seem like an alluring way to contribute to Ruby, often these
-discussions can lead nowhere and exhaust time and energy that could be better
-spent fixing bugs. Choose your battles.
-
-A good template for a feature proposal should look something like this:
-
-[Abstract]
-  Summary of your feature
-[Background]
-  Describe current behavior and why it is problem. Related work, such as
-  solutions in other language helps us to understand the problem.
-[Proposal]
-  Describe your proposal in details
-[Details]
-  If it has complicated feature, describe it
-[Usecase]
-  How would your feature be used? Who will benefit from it?
-[Discussion]
-  Discuss about this proposal. A list of pros and cons will help start
-  discussion.
-[Limitation]
-  Limitation of your proposal
-[Another alternative proposal]
-  If there are alternative proposals, show them.
-[See also]
-  Links to the other related resources
-
-== Backport Requests
-
-When a new version of Ruby is released, it starts at patch level 0 (p0), and
-bugs will be fixed first on the master branch. If it's determined that a bug
-exists in a previous version of Ruby that is still in the bug fix stage of
-maintenance, then a patch will be backported. After the maintenance stage of a
-particular Ruby version ends, it goes into "security fix only" mode which
-means only security related vulnerabilities will be backported. Versions in
-End-of-life (EOL) will not receive any updates and it is recommended you
-upgrade as soon as possible.
-
-If a major security issue is found or after a certain amount of time since the
-last patch level release, a new patch-level release will be made.
-
-When submitting a backport request please confirm the bug has been fixed in
-newer versions and exists in maintenance mode versions. There is a backport
-tracker for each major version still in maintenance where you can request a
-particular revision merged in the affected version of Ruby.
-
-Each major version of Ruby has a release manager that should be assigned to
-handle backport requests. You can find the list of release managers on the
-{wiki}[https://bugs.ruby-lang.org/projects/ruby/wiki/ReleaseEngineering].
-
-=== Branches
-
-Status and maintainers of branches are listed on the
-{wiki}[https://bugs.ruby-lang.org/projects/ruby/wiki/ReleaseEngineering].
-
-== Running tests
-
-In order to help resolve existing issues and contributing patches to Ruby you
-need to be able to run the test suite.
-
-CRuby uses git for source control, the {git homepage}[https://git-scm.com/]
-has installation instructions with links to documentation for learning more
-about git. There is a mirror of the repository on {github}[https://github.com/ruby/ruby].
-For other resources see the {ruby-core documentation on
-ruby-lang.org}[https://www.ruby-lang.org/en/community/ruby-core/].
-
-Install the prerequisite dependencies for building the CRuby interpreter to
-run tests.
-
-* C compiler
-* autoconf - 2.67 or later, preferably 2.69.
-* bison - 2.0 or later, preferably 3.4.
-* gperf - 3.0.3 or later, preferably 3.1.
-* ruby - Ruby itself is prerequisite in order to build Ruby from source.
-  You should use [a maintained version of Ruby](https://www.ruby-lang.org/en/downloads/).
-
-You should also have access to development headers for the following
-libraries, but these are not required:
-
-* NDBM/QDBM
-* GDBM
-* OpenSSL/LibreSSL
-* readline/editline(libedit)
-* zlib
-* libffi
-* libyaml
-* libexecinfo (FreeBSD)
-
-Now let's build CRuby:
-
-* Checkout the CRuby source code:
-
-    git clone https://github.com/ruby/ruby.git ruby-master
-
-* Generate the configuration files and build:
-
-    cd ruby-master
-    ./autogen.sh
-    mkdir build && cd build # its good practice to build outside of source dir
-    mkdir ~/.rubies # we will install to .rubies/ruby-master in our home dir
-    ../configure --prefix="${HOME}/.rubies/ruby-master"
-    make up && make install
-
-After adding Ruby to your PATH, you should be ready to run the test suite:
-
-    make test
-
-You can also use +test-all+ to run all of the tests with the RUNRUBY
-interpreter just built. Use TESTS or RUNRUBYOPT to pass parameters, such as:
-
-    make test-all TESTS=-v
-
-This is also how you can run a specific test from our build dir:
-
-    make test-all TESTS=drb/test_drb.rb
-
-You can run +test+ and +test-all+ at once by +check+ .
-
-    make check
-
-For older versions of Ruby you will need to run the build setup again after
-checking out the associated branch in git, for example if you wanted to
-checkout 1.9.3:
-
-    git clone https://github.com/ruby/ruby.git --branch ruby_1_9_3
-
-Once you checked out the source code, you can update the local copy by:
-
-    make up
-
-Or, update, build, install and check, by just:
-
-    make love
-
-== Contributing Documentation
-
-If you're interested in contributing documentation directly to CRuby there is
-some information available at
-{Contributing}[https://github.com/ruby/ruby#contributing].
-
-There is also the {Ruby Reference
-Manual}[https://github.com/rurema/doctree/wiki] in Japanese.
-
-== Contributing A Patch
-
-=== Deciding what to patch
-
-Before you submit a patch, there are a few things you should know:
-
-* Pay attention to the maintenance policy for stable and maintained versions of Ruby.
-* Released versions in security mode will not merge feature changes.
-* Search for previous discussions on ruby-core to verify the maintenance policy
-* Patches must be distributed under Ruby's license.
-* This license may change in the future, you must join the discussion if you don't agree to the change
-
-To improve the chance your patch will be accepted please follow these simple rules:
-
-* Bug fixes should be committed on master first
-* Format of the patch file must be a unified diff (ie: diff -pu, svn diff, or git diff)
-* Don't introduce cosmetic changes
-* Follow the original coding style of the code
-* Don't mix different changes in one commit
-
-First thing you should do is check out the code if you haven't already:
-
-  git clone https://github.com/ruby/ruby.git ruby-master
-
-Now create a dedicated branch:
-
-  cd ruby-master
-  git checkout -b my_new_branch
-
-The name of your branch doesn't really matter because it will only exist on
-your local computer and won't be part of the official Ruby repository. It will
-be used to create patches based on the differences between your branch and
-master, or edge Ruby.
-
-=== Coding style
-
-Here are some general rules to follow when writing Ruby and C code for CRuby:
-
-* Indent 4 spaces for C without tabs (old codes might use tabs for eight-space indentation,
-  but newer codes recommend to use spaces only)
-* Indent 2 space tabs for Ruby
-* Do not use TABs in ruby codes
-* ANSI C style for 1.9+ for function declarations
-* Follow C90 (not C99) Standard
-* PascalStyle for class/module names.
-* UNDERSCORE_SEPARATED_UPPER_CASE for other constants.
-* Capitalize words.
-* ABBRs should be all upper case.
-* Do as others do
-
-=== Commit messages
-
-When you're ready to commit:
-
-   git commit path/to/files
-
-This will open your editor in which you write your commit message.
-Use the following style for commit messages:
-
-* Use a succinct subject line.
-* Include reasoning behind the change in the commit message, focusing on why
-  the change is being made.
-* Refer to redmine issue (such as Fixes [Bug #1234] or Implements
-  [Feature #3456]), or discussion on the mailing list
-  (such as [ruby-core:12345]).
-* For GitHub issues, use [GH-#] (such as [Fixes GH-234]).
-* Follow the style used by other committers.
-
-=== Contributing your code
-
-Now that you've got some code you want to contribute, let's get set up to
-generate a patch. Start by forking the github mirror, check the {github docs on
-forking}[https://help.github.com/articles/fork-a-repo] if you get stuck here.
-You will only need a github account if you intend to host your repository
-on github.
-
-Next copy the writable url for your fork and add it as a git remote, replace
-"my_username" with your github account name:
-
-    git remote add my_fork git@github.com:my_username/ruby.git
-    # Now we can push our branch to our fork
-    git push my_fork my_new_branch
-
-In order to generate a patch that you can upload to the bug tracker, we can use
-the github interface to review our changes just visit
-https://github.com/my_username/ruby/compare/master...my_new_branch
-
-Next, you can simply add '.patch' to the end of this URL and it will generate
-the patch for you, save the file to your computer and upload it to the bug
-tracker. Alternatively you can submit a pull request, but for the best chances
-to receive feedback add it is recommended you add it to redmine.
-
-Since git is a distributed system, you are welcome to host your git repository
-on any {publicly accessible hosting
-site}[https://git.wiki.kernel.org/index.php/GitHosting], including {hosting your
-own}[https://www.kernel.org/pub/software/scm/git/docs/user-manual.html#public-repositories]
-You may use the {'git format-patch'}[https://git-scm.com/docs/git-format-patch]
-command to generate patch files to upload to redmine.  You may also use
-the {'git request-pull'}[https://git-scm.com/docs/git-request-pull] command for
-formatting pull request messages to redmine.
-
-=== Updating the official repository
-
-If you are a committer, you can push changes directly into the official
-repository:
-
-    git push origin your-branch-name:master
-
-However, it is likely will have become outdated, and you will have to
-update it.  In that case, run:
-
-    git fetch origin
-    git rebase remotes/origin/master
-
-and then try pushing your changes again.
diff --git a/doc/contributing/building_ruby.md b/doc/contributing/building_ruby.md
new file mode 100644
index 0000000000..469c9d8361
--- /dev/null
+++ b/doc/contributing/building_ruby.md
@@ -0,0 +1,172 @@
+# Building Ruby
+
+## Quick start guide
+
+1. Install the prerequisite dependencies for building the CRuby interpreter:
+
+    * C compiler
+    * autoconf - 2.67 or later
+    * bison - 3.0 or later
+    * gperf - 3.0.3 or later
+    * ruby - 2.7 or later
+
+2. Install optional, recommended dependencies:
+
+    * OpenSSL/LibreSSL
+    * readline/editline (libedit)
+    * zlib
+    * libffi
+    * libyaml
+    * libexecinfo (FreeBSD)
+    * rustc - 1.58.0 or later (if you wish to build [YJIT](/doc/yjit/yjit.md))
+
+3. Checkout the CRuby source code:
+
+    ```
+    git clone https://github.com/ruby/ruby.git
+    ```
+
+4. Generate the configure file:
+
+    ```
+    ./autogen.sh
+    ```
+
+5. Create a `build` directory outside of the source directory:
+
+    ```
+    mkdir build && cd build
+    ```
+
+    While it's not necessary to build in a separate directory, it's good practice to do so.
+
+6. We'll install Ruby in `~/.rubies/ruby-master`, so create the directory:
+
+    ```
+    mkdir ~/.rubies
+    ```
+
+7. Run configure:
+
+    ```
+    ../configure --prefix="${HOME}/.rubies/ruby-master"
+    ```
+
+    - If you are frequently building Ruby, add the `--disable-install-doc` flag to not build documentation which will speed up the build process.
+
+8. Build Ruby:
+
+    ```
+    make install
+    ```
+
+    - If you're on macOS and installed \OpenSSL through Homebrew, you may encounter failure to build \OpenSSL that look like this:
+
+        ```
+        openssl:
+            Could not be configured. It will not be installed.
+            ruby/ext/openssl/extconf.rb: OpenSSL library could not be found. You might want to use --with-openssl-dir=<dir> option to specify the prefix where OpenSSL is installed.
+            Check ext/openssl/mkmf.log for more details.
+        ```
+
+        Adding `--with-openssl-dir=$(brew --prefix openssl)` to the list of options passed to configure may solve the issue.
+
+        Remember to delete your `build` directory and start again from the configure step.
+
+9. [Run tests](testing_ruby.md) to confirm your build succeeded.
+
+### Unexplainable Build Errors
+
+If you are having unexplainable build errors, after saving all your work, try running `git clean -xfd` in the source root to remove all git ignored local files. If you are working from a source directory that's been updated several times, you may have temporary build artifacts from previous releases which can cause build failures.
+
+## More details
+
+If you're interested in continuing development on Ruby, here are more details
+about Ruby's build to help out.
+
+### Running make scripts in parallel
+
+In GNU make and BSD make implementations, to run a specific make script in parallel, pass the flag `-j<number of processes>`. For instance,
+to run tests on 8 processes, use:
+
+```
+make test-all -j8
+```
+
+We can also set `MAKEFLAGS` to run _all_ `make` commands in parallel.
+
+Having the right `--jobs` flag will ensure all processors are utilized when building software projects. To do this effectively, you can set `MAKEFLAGS` in your shell configuration/profile:
+
+``` shell
+# On macOS with Fish shell:
+export MAKEFLAGS="--jobs "(sysctl -n hw.ncpu)
+
+# On macOS with Bash/ZSH shell:
+export MAKEFLAGS="--jobs $(sysctl -n hw.ncpu)"
+
+# On Linux with Fish shell:
+export MAKEFLAGS="--jobs "(nproc)
+
+# On Linux with Bash/ZSH shell:
+export MAKEFLAGS="--jobs $(nproc)"
+```
+
+### Miniruby vs Ruby
+
+Miniruby is a version of Ruby which has no external dependencies and lacks certain features.
+It can be useful in Ruby development because it allows for faster build times. Miniruby is
+built before Ruby. A functional Miniruby is required to build Ruby. To build Miniruby:
+
+```
+make miniruby
+```
+
+## Debugging
+
+You can use either lldb or gdb for debugging. Before debugging, you need to create a `test.rb`
+with the Ruby script you'd like to run. You can use the following make targets:
+
+* `make run`: Runs `test.rb` using Miniruby
+* `make lldb`: Runs `test.rb` using Miniruby in lldb
+* `make gdb`: Runs `test.rb` using Miniruby in gdb
+* `make runruby`: Runs `test.rb` using Ruby
+* `make lldb-ruby`: Runs `test.rb` using Ruby in lldb
+* `make gdb-ruby`: Runs `test.rb` using Ruby in gdb
+
+### Building with Address Sanitizer
+
+Using the address sanitizer is a great way to detect memory issues.
+
+``` shell
+./autogen.sh
+mkdir build && cd build
+export ASAN_OPTIONS="halt_on_error=0:use_sigaltstack=0:detect_leaks=0"
+../configure cppflags="-fsanitize=address -fno-omit-frame-pointer" optflags=-O0 LDFLAGS="-fsanitize=address -fno-omit-frame-pointer"
+make
+```
+
+On Linux it is important to specify `-O0` when debugging. This is especially true for ASAN which sometimes works incorrectly at higher optimisation levels.
+
+## How to measure coverage of C and Ruby code
+
+You need to be able to use gcc (gcov) and lcov visualizer.
+
+```
+./autogen.sh
+./configure --enable-gcov
+make
+make update-coverage
+rm -f test-coverage.dat
+make test-all COVERAGE=true
+make lcov
+open lcov-out/index.html
+```
+
+If you need only C code coverage, you can remove `COVERAGE=true` from the above process.
+You can also use `gcov` command directly to get per-file coverage.
+
+If you need only Ruby code coverage, you can remove `--enable-gcov`.
+Note that `test-coverage.dat` accumulates all runs of `make test-all`.
+Make sure that you remove the file if you want to measure one test run.
+
+You can see the coverage result of CI: https://rubyci.org/coverage
diff --git a/doc/contributing/documentation_guide.md b/doc/contributing/documentation_guide.md
new file mode 100644
index 0000000000..9cfd59d629
--- /dev/null
+++ b/doc/contributing/documentation_guide.md
@@ -0,0 +1,435 @@
+# Documentation Guide
+
+This guide discusses recommendations for documenting
+classes, modules, and methods
+in the Ruby core and in the Ruby standard library.
+
+## Generating documentation
+
+Most Ruby documentation lives in the source files and is written in
+[RDoc format](rdoc-ref:RDoc::Markup).
+
+Some pages live under the `doc` folder and can be written in either
+`.rdoc` or `.md` format, determined by the file extension.
+
+To generate the output of documentation changes in HTML in the
+`{build folder}/.ext/html` directory, run the following inside your
+build directory:
+
+```sh
+make html
+```
+
+Then you can preview your changes by opening
+`{build folder}/.ext/html/index.html` file in your browser.
+
+
+## Goal
+
+The goal of Ruby documentation is to impart the most important
+and relevant in the shortest time.
+The reader should be able to quickly understand the usefulness
+of the subject code and how to use it.
+
+Providing too little information is bad, but providing unimportant
+information or unnecessary examples is not good either.
+Use your judgment about what the user needs to know.
+
+## General Guidelines
+
+- Keep in mind that the reader may not be fluent in \English.
+- Write short declarative or imperative sentences.
+- Group sentences into (ideally short) paragraphs,
+  each covering a single topic.
+- Organize material with [headers](rdoc-ref:RDoc::Markup@Headers).
+- Refer to authoritative and relevant sources using
+  [links](rdoc-ref:RDoc::Markup@Links).
+- Use simple verb tenses: simple present, simple past, simple future.
+- Use simple sentence structure, not compound or complex structure.
+- Avoid:
+    - Excessive comma-separated phrases;
+      consider a [list](rdoc-ref:RDoc::Markup@Simple+Lists).
+    - Idioms and culture-specific references.
+    - Overuse of headers.
+    - Using US-ASCII-incompatible characters in C source files;
+      see [Characters](#label-Characters) below.
+
+### Characters
+
+Use only US-ASCII-compatible characters in a C source file.
+(If you use other characters, the Ruby CI will gently let you know.)
+
+If want to put ASCII-incompatible characters into the documentation
+for a C-coded class, module, or method, there are workarounds
+involving new files `doc/*.rdoc`:
+
+- For class `Foo` (defined in file `foo.c`),
+  create file `doc/foo.rdoc`, declare `class Foo; end`,
+  and place the class documentation above that declaration:
+
+    ```ruby
+    # Documentation for class Foo goes here.
+    class Foo; end
+    ```
+
+- Similarly, for module `Bar` (defined in file `bar.c`,
+  create file `doc/bar.rdoc`, declare `module Bar; end`,
+  and place the module documentation above that declaration:
+
+    ```ruby
+    # Documentation for module Bar goes here.
+    module Bar; end
+    ```
+
+- For a method, things are different.
+  Documenting a method as above disables the "click to toggle source" feature
+  in the rendered documentation.
+
+    Therefore it's best to use file inclusion:
+
+    - Retain the `call-seq` in the C code.
+    - Use file inclusion (`:include:`) to include text from an .rdoc file.
+
+    Example:
+
+    ```
+    /*
+     *  call-seq:
+     *    each_byte {|byte| ... } -> self
+     *    each_byte               -> enumerator
+     *
+     *  :include: doc/string/each_byte.rdoc
+     *
+     */
+    ```
+
+### \RDoc
+
+Ruby is documented using RDoc.
+For information on \RDoc syntax and features, see the
+[RDoc Markup Reference](rdoc-ref:RDoc::Markup@RDoc+Markup+Reference).
+
+### Output from `irb`
+
+For code examples, consider using interactive Ruby,
+[irb](https://ruby-doc.org/stdlib/libdoc/irb/rdoc/IRB.html).
+
+For a code example that includes `irb` output,
+consider aligning `# => ...` in successive lines.
+Alignment may sometimes aid readability:
+
+```ruby
+a = [1, 2, 3] #=> [1, 2, 3]
+a.shuffle!    #=> [2, 3, 1]
+a             #=> [2, 3, 1]
+```
+
+### Headers
+
+Organize a long discussion with [headers](rdoc-ref:RDoc::Markup@Headers).
+
+### Blank Lines
+
+A blank line begins a new paragraph.
+
+A [code block](rdoc-ref:RDoc::Markup@Paragraphs+and+Verbatim)
+or [list](rdoc-ref:RDoc::Markup@Simple+Lists)
+should be preceded by and followed by a blank line.
+This is unnecessary for the HTML output, but helps in the `ri` output.
+
+### \Method Names
+
+For a method name in text:
+
+- For a method in the current class or module,
+  use a double-colon for a singleton method,
+  or a hash mark for an instance method:
+  <tt>::bar</tt>, <tt>#baz</tt>.
+- Otherwise, include the class or module name
+  and use a dot for a singleton method,
+  or a hash mark for an instance method:
+  <tt>Foo.bar</tt>, <tt>Foo#baz</tt>.
+
+### Auto-Linking
+
+In general, \RDoc's auto-linking should not be suppressed.
+For example, we should write `Array`, not `\Array`.
+
+We might consider whether to suppress when:
+
+- The word in question does not refer to a Ruby entity
+  (e.g., some uses of _Class_ or _English_).
+- The reference is to the current class document
+  (e.g., _Array_ in the documentation for class `Array`).
+- The same reference is repeated many times
+  (e.g., _RDoc_ on this page).
+
+### HTML Tags
+
+In general, avoid using HTML tags (even in formats where it's allowed)
+because `ri` (the Ruby Interactive reference tool)
+may not render them properly.
+
+### Tables
+
+In particular, avoid building tables with HTML tags
+(<tt><table></tt>, etc.).
+
+Alternatives are:
+
+- The GFM (GitHub Flavored Markdown) table extension,
+  which is enabled by default. See
+  {GFM tables extension}[https://github.github.com/gfm/#tables-extension-].
+
+- A {verbatim text block}[rdoc-ref:RDoc::MarkupReference@Verbatim+Text+Blocks],
+  using spaces and punctuation to format the text.
+  Note that {text markup}[rdoc-ref:RDoc::MarkupReference@Text+Markup]
+  will not be honored.
+
+## Documenting Classes and Modules
+
+The general structure of the class or module documentation should be:
+
+- Synopsis
+- Common uses, with examples
+- "What's Here" summary (optional)
+
+### Synopsis
+
+The synopsis is a short description of what the class or module does
+and why the reader might want to use it.
+Avoid details in the synopsis.
+
+### Common Uses
+
+Show common uses of the class or module.
+Depending on the class or module, this section may vary greatly
+in both length and complexity.
+
+### What's Here Summary
+
+The documentation for a class or module may include a "What's Here" section.
+
+Guidelines:
+
+- The section title is `What's Here`.
+- Consider listing the parent class and any included modules; consider
+  [links](rdoc-ref:RDoc::Markup@Links)
+  to their "What's Here" sections if those exist.
+- List methods as a bullet list:
+
+    - Begin each item with the method name, followed by a colon
+      and a short description.
+    - If the method has aliases, mention them in parentheses before the colon
+      (and do not list the aliases separately).
+    - Check the rendered documentation to determine whether \RDoc has recognized
+      the method and linked to it;  if not, manually insert a
+      [link](rdoc-ref:RDoc::Markup@Links).
+
+- If there are numerous entries, consider grouping them into subsections with headers.
+- If there are more than a few such subsections,
+  consider adding a table of contents just below the main section title.
+
+## Documenting Methods
+
+### General Structure
+
+The general structure of the method documentation should be:
+
+- Calling sequence (for methods written in C).
+- Synopsis (short description).
+- Details and examples.
+- Argument description (if necessary).
+- Corner cases and exceptions.
+- Aliases.
+- Related methods (optional).
+
+### Calling Sequence (for methods written in C)
+
+For methods written in Ruby, \RDoc documents the calling sequence automatically.
+
+For methods written in C, \RDoc cannot determine what arguments
+the method accepts, so those need to be documented using \RDoc directive
+[`call-seq:`](rdoc-ref:RDoc::Markup@Method+arguments).
+
+For a singleton method, use the form:
+
+```
+class_name.method_name(method_args) {|block_args| ... } -> return_type
+```
+
+Example:
+
+```
+*  call-seq:
+*    Hash.new(default_value = nil) -> new_hash
+*    Hash.new {|hash, key| ... } -> new_hash
+```
+
+For an instance method, use the form
+(omitting any prefix, just as RDoc does for a Ruby-coded method):
+
+```
+method_name(method_args) {|block_args| ... } -> return_type
+```
+For example, in Array, use:
+
+```
+*  call-seq:
+*    count -> integer
+*    count(obj) -> integer
+*    count {|element| ... } -> integer
+```
+
+```
+* call-seq:
+*    <=> other -> -1, 0, 1, or nil
+```
+
+Arguments:
+
+- If the method does not accept arguments, omit the parentheses.
+- If the method accepts optional arguments:
+
+    - Separate each argument name and its default value with ` = `
+      (equal-sign with surrounding spaces).
+    - If the method has the same behavior with either an omitted
+      or an explicit argument, use a `call-seq` with optional arguments.
+      For example, use:
+
+        ```
+        respond_to?(symbol, include_all = false) -> true or false
+        ```
+
+    - If the behavior is different with an omitted or an explicit argument,
+      use a `call-seq` with separate lines.
+      For example, in Enumerable, use:
+
+        ```
+        *    max    -> element
+        *    max(n) -> array
+        ```
+
+Block:
+
+- If the method does not accept a block, omit the block.
+- If the method accepts a block, the `call-seq` should have `{|args| ... }`,
+  not `{|args| block }` or `{|args| code }`.
+
+Return types:
+
+- If the method can return multiple different types,
+  separate the types with "or" and, if necessary, commas.
+- If the method can return multiple types, use +object+.
+- If the method returns the receiver, use +self+.
+- If the method returns an object of the same class,
+  prefix `new_` if an only if the object is not  +self+;
+  example: `new_array`.
+
+Aliases:
+
+- Omit aliases from the `call-seq`, but mention them near the end (see below).
+
+### Synopsis
+
+The synopsis comes next, and is a short description of what the
+method does and why you would want to use it.  Ideally, this
+is a single sentence, but for more complex methods it may require
+an entire paragraph.
+
+For `Array#count`, the synopsis is:
+
+```
+Returns a count of specified elements.
+```
+
+This is great as it is short and descriptive.  Avoid documenting
+too much in the synopsis, stick to the most important information
+for the benefit of the reader.
+
+### Details and Examples
+
+Most non-trivial methods benefit from examples, as well as details
+beyond what is given in the synopsis.  In the details and examples
+section, you can document how the method handles different types
+of arguments, and provides examples on proper usage.  In this
+section, focus on how to use the method properly, not on how the
+method handles improper arguments or corner cases.
+
+Not every behavior of a method requires an example.  If the method
+is documented to return `self`, you don't need to provide an example
+showing the return value is the same as the receiver.  If the method
+is documented to return `nil`, you don't need to provide an example
+showing that it returns `nil`.  If the details mention that for a
+certain argument type, an empty array is returned, you don't need
+to provide an example for that.
+
+Only add an example if it provides the user additional information,
+do not add an example if it provides the same information given
+in the synopsis or details.  The purpose of examples is not to prove
+what the details are stating.
+
+### Argument Description (if necessary)
+
+For methods that require arguments, if not obvious and not explicitly
+mentioned in the details or implicitly shown in the examples, you can
+provide details about the types of arguments supported.  When discussing
+the types of arguments, use simple language even if less-precise, such
+as "level must be an integer", not "level must be an Integer-convertible
+object".  The vast majority of use will be with the expected type, not an
+argument that is explicitly convertible to the expected type, and
+documenting the difference is not important.
+
+For methods that take blocks, it can be useful to document the type of
+argument passed if it is not obvious, not explicitly mentioned in the
+details, and not implicitly shown in the examples.
+
+If there is more than one argument or block argument, use a
+[labeled list](rdoc-ref:RDoc::Markup@Labeled+Lists).
+
+### Corner Cases and Exceptions
+
+For corner cases of methods, such as atypical usage, briefly mention
+the behavior, but do not provide any examples.
+
+Only document exceptions raised if they are not obvious.  For example,
+if you have stated earlier than an argument type must be an integer,
+you do not need to document that a `TypeError` is raised if a non-integer
+is passed.  Do not provide examples of exceptions being raised unless
+that is a common case, such as `Hash#fetch` raising a `KeyError`.
+
+### Aliases
+
+Mention aliases in the form
+
+```
+// Array#find_index is an alias for Array#index.
+```
+
+### Related Methods (optional)
+
+In some cases, it is useful to document which methods are related to
+the current method.  For example, documentation for `Hash#[]` might
+mention `Hash#fetch` as a related method, and `Hash#merge` might mention
+`Hash#merge!` as a related method.
+
+- Consider which methods may be related
+  to the current method, and if you think the reader would benefit it,
+  at the end of the method documentation, add a line starting with
+  "Related: " (e.g. "Related: #fetch.").
+- Don't list more than three related methods.
+  If you think more than three methods are related,
+  list the three you think are most important.
+- Consider adding:
+
+    - A phrase suggesting how the related method is similar to,
+      or different from,the current method.
+      See an example at Time#getutc.
+    - Example code that illustrates the similarities and differences.
+      See examples at Time#ctime, Time#inspect, Time#to_s.
+
+### Methods Accepting Multiple Argument Types
+
+For methods that accept multiple argument types, in some cases it can
+be useful to document the different argument types separately.  It's
+best to use a separate paragraph for each case you are discussing.
diff --git a/doc/contributing/making_changes_to_ruby.md b/doc/contributing/making_changes_to_ruby.md
new file mode 100644
index 0000000000..260fadb7e3
--- /dev/null
+++ b/doc/contributing/making_changes_to_ruby.md
@@ -0,0 +1,28 @@
+# Contributing a pull request
+
+## Code style
+
+Here are some general rules to follow when writing Ruby and C code for CRuby:
+
+* Do not change code unrelated to your pull request (including style fixes)
+* Indent 4 spaces for C without tabs (tabs are two levels of indentation, equivalent to 8 spaces)
+* Indent 2 spaces for Ruby without tabs
+* ANSI C style for function declarations
+* Follow C99 Standard
+* PascalStyle for class/module names
+* UNDERSCORE_SEPARATED_UPPER_CASE for other constants
+* Abbreviations should be all upper case
+
+## Commit messages
+
+Use the following style for commit messages:
+
+* Use a succinct subject line
+* Include reasoning behind the change in the commit message, focusing on why the change is being made
+* Refer to  issue (such as `Fixes [Bug #1234]` or `Implements [Feature #3456]`), or discussion on the mailing list (such as [ruby-core:12345])
+
+## CI
+
+GitHub actions will run on each pull request.
+
+There is [a CI that runs on master](https://rubyci.org/). It has broad coverage of different systems and architectures, such as Solaris SPARC and macOS.
diff --git a/doc/contributing/making_changes_to_stdlibs.md b/doc/contributing/making_changes_to_stdlibs.md
new file mode 100644
index 0000000000..ef3811ea12
--- /dev/null
+++ b/doc/contributing/making_changes_to_stdlibs.md
@@ -0,0 +1,49 @@
+# Making Changes To Standard Libraries
+
+Everything in the [lib](https://github.com/ruby/ruby/tree/master/lib) directory is mirrored from a standalone repository into the Ruby repository.
+If you'd like to make contributions to standard libraries, do so in the standalone repositories, and the
+changes will be automatically mirrored into the Ruby repository.
+
+For example, CSV lives in [a separate repository](https://github.com/ruby/csv) and is mirrored into [Ruby](https://github.com/ruby/ruby/tree/master/lib/csv).
+
+## Maintainers
+
+You can find the list of maintainers [here](https://docs.ruby-lang.org/en/master/maintainers_rdoc.html#label-Maintainers).
+
+## Build
+
+First, install its dependencies using:
+
+```
+bundle install
+```
+
+### Libraries with C-extension
+
+If the library has a `/ext` directory, it has C files that you need to compile with:
+
+```
+bundle exec rake compile
+```
+
+## Running tests
+
+All standard libraries use [test-unit](https://github.com/test-unit/test-unit) as the test framework.
+
+To run all tests:
+
+```
+bundle exec rake test
+```
+
+To run a single test file:
+
+```
+bundle exec rake test TEST="test/test_foo.rb"
+```
+
+To run a single test case:
+
+```
+bundle exec rake test TEST="test/test_foo.rb" TESTOPS="--name=/test_mytest/"
+```
diff --git a/doc/contributing/reporting_issues.md b/doc/contributing/reporting_issues.md
new file mode 100644
index 0000000000..25516ffc6b
--- /dev/null
+++ b/doc/contributing/reporting_issues.md
@@ -0,0 +1,91 @@
+# Reporting Issues
+## Reporting security issues
+
+If you've found a security vulnerability, please follow
+[these instructions](https://www.ruby-lang.org/en/security/).
+
+## Reporting bugs
+
+If you've encountered a bug in Ruby, please report it to the Redmine issue
+tracker available at [bugs.ruby-lang.org](https://bugs.ruby-lang.org/), by
+following these steps:
+
+* Check if anyone has already reported your issue by
+  searching [the Redmine issue tracker](https://bugs.ruby-lang.org/projects/ruby-master/issues).
+* If you haven't already,
+  [sign up for an account](https://bugs.ruby-lang.org/account/register) on the
+  Redmine issue tracker.
+* If you can't find a ticket addressing your issue, please [create a new issue](https://bugs.ruby-lang.org/projects/ruby-master/issues/new). You will need to fill in the subject, description and Ruby version.
+
+    * Ensure the issue exists on Ruby master by trying to replicate your bug on
+      the head of master (see ["making changes to Ruby"](making_changes_to_ruby.md)).
+    * Write a concise subject and briefly describe your problem in the description section. If
+      your issue affects [a released version of Ruby](#label-Backport+requests), please say so.
+    * Fill in the Ruby version you're using when experiencing this issue
+      (the output of running `ruby -v`).
+    * Attach any logs or reproducible programs to provide additional information.
+      Any scripts should be as small as possible.
+* If the ticket doesn't have any replies after 10 days, you can send a
+  reminder.
+* Please reply to feedback requests. If a bug report doesn't get any feedback,
+  it'll eventually get rejected.
+
+### Reporting website issues
+
+If you're having an issue with the bug tracker or the mailing list, you can
+contact the webmaster, Hiroshi SHIBATA (hsbt@ruby-lang.org).
+
+You can report issues with ruby-lang.org on the
+[repo's issue tracker](https://github.com/ruby/www.ruby-lang.org/issues).
+
+## Requesting features
+
+If there's a new feature that you want to see added to Ruby, you will need to
+write a proposal on [the Redmine issue tracker](https://bugs.ruby-lang.org/projects/ruby-master/issues/new).
+When you open the issue, select `Feature` in the Tracker dropdown.
+
+When writing a proposal, be sure to check for previous discussions on the
+topic and have a solid use case. You should also consider the potential
+compatibility issues that this new feature might raise. Consider making
+your feature into a gem, and if there are enough people who benefit from
+your feature it could help persuade Ruby core.
+
+Here is a template you can use for a feature proposal:
+
+```
+[Abstract]
+  Briefly summarize your feature
+[Background]
+  Describe current behavior
+[Proposal]
+  Describe your feature in detail
+[Use cases]
+  Give specific example uses of your feature
+[Discussion]
+  Describe why this feature is necessary and better than using existing features
+[See also]
+  Link to other related resources (such as implementations in other languages)
+```
+
+## Backport requests
+
+If a bug exists in a released version of Ruby, please report this in the issue.
+Once this bug is fixed, the fix can be backported if deemed necessary. Only Ruby
+committers can request backporting, and backporting is done by the backport manager.
+New patch versions are released at the discretion of the backport manager.
+
+[Ruby versions](https://www.ruby-lang.org/en/downloads/) can be in one of three maintenance states:
+
+* Stable releases: backport any bug fixes
+* Security maintenance: only backport security fixes
+* End of life: no backports, please upgrade your Ruby version
+
+## Add context to existing issues
+
+There are several ways you can help with a bug that aren't directly
+resolving it. These include:
+
+* Verifying or reproducing the existing issue and reporting it
+* Adding more specific reproduction instructions
+* Contributing a failing test as a patch (see ["making changes to Ruby"](making_changes_to_ruby.md))
+* Testing patches that others have submitted (see ["making changes to Ruby"](making_changes_to_ruby.md))
diff --git a/doc/contributing/testing_ruby.md b/doc/contributing/testing_ruby.md
new file mode 100644
index 0000000000..6247686efc
--- /dev/null
+++ b/doc/contributing/testing_ruby.md
@@ -0,0 +1,138 @@
+# Testing Ruby
+
+## Test suites
+
+There are several test suites in the Ruby codebase:
+
+We can run any of the make scripts [in parallel](building_ruby.md#label-Running+make+scripts+in+parallel) to speed them up.
+
+1. [bootstraptest/](https://github.com/ruby/ruby/tree/master/bootstraptest)
+
+    This is a small test suite that runs on Miniruby (see [building Ruby](building_ruby.md#label-Miniruby+vs+Ruby)). We can run it with:
+
+    ```
+    make btest
+    ```
+
+    To run it with logs, we can use:
+
+    ```
+    make btest OPTS=-v
+    ```
+
+    To run individual bootstrap tests, we can either specify a list of filenames or use the `--sets` flag in the variable `BTESTS`:
+
+    ```
+    make btest BTESTS="bootstraptest/test_fork.rb bootstraptest/tes_gc.rb"
+    make btest BTESTS="--sets=fork,gc"
+    ```
+
+    If we want to run the bootstrap test suite on Ruby (not Miniruby), we can use:
+
+    ```
+    make test
+    ```
+
+    To run it with logs, we can use:
+
+    ```
+    make test OPTS=-v
+    ```
+
+    To run a file or directory with GNU make, we can use:
+
+    ```
+    make test/ruby/test_foo.rb
+    make test/ruby/test_foo.rb TESTOPTS="-n /test_bar/"
+    ```
+
+2. [test/](https://github.com/ruby/ruby/tree/master/test)
+
+    This is a more comprehensive test suite that runs on Ruby. We can run it with:
+
+    ```
+    make test-all
+    ```
+
+    We can run a specific test directory in this suite using the `TESTS` option, for example:
+
+    ```
+    make test-all TESTS=test/rubygems
+    ```
+
+    We can run a specific test file in this suite by also using the `TESTS` option, for example:
+
+    ```
+    make test-all TESTS=test/ruby/test_array.rb
+    ```
+
+    We can run a specific test in this suite using the `TESTS` option, specifying
+    first the file name, and then the test name, prefixed with `--name`. For example:
+
+    ```
+    make test-all TESTS="../test/ruby/test_alias.rb --name=/test_alias_with_zsuper_method/"
+    ```
+
+    To run these specs with logs, we can use:
+
+    ```
+    make test-all TESTS=-v
+    ```
+
+    If we would like to run both the `test/` and `bootstraptest/` test suites, we can run
+
+    ```
+    make check
+    ```
+
+3. [spec/ruby](https://github.com/ruby/ruby/tree/master/spec/ruby)
+
+    This is a test suite that exists in [the Ruby spec repository](https://github.com/ruby/spec) and is mirrored into the `spec/ruby` directory in the Ruby repository. It tests the behavior of the Ruby programming language. We can run this using:
+
+    ```
+    make test-spec
+    ```
+
+    To run a specific directory, we can use `MSPECOPT` to specify the directory:
+
+    ```
+    make test-spec MSPECOPT=spec/ruby/core/array
+    ```
+
+    To run a specific file, we can also use `MSPECOPT` to specify the file:
+
+    ```
+    make test-spec MSPECOPT=spec/ruby/core/array/any_spec.rb
+    ```
+
+    To run a specific test, we can use the `--example` flag to match against the test name:
+
+    ```
+    make test-spec MSPECOPT="../spec/ruby/core/array/any_spec.rb --example='is false if the array is empty'"
+    ```
+
+    To run these specs with logs, we can use:
+
+    ```
+    make test-spec MSPECOPT=-Vfs
+    ```
+
+    To run a ruby-spec file or directory with GNU make, we can use
+
+    ```
+    make spec/ruby/core/foo/bar_spec.rb
+    ```
+
+4. [spec/bundler](https://github.com/ruby/ruby/tree/master/spec/bundler)
+
+    The bundler test suite exists in [the RubyGems repository](https://github.com/rubygems/rubygems/tree/master/bundler/spec) and is mirrored into the `spec/bundler` directory in the Ruby repository. We can run this using:
+
+    ```
+    make test-bundler
+    ```
+
+    To run a specific bundler spec file, we can use `BUNDLER_SPECS` as follows:
+
+    ```
+    $ make test-bundler BUNDLER_SPECS=commands/exec_spec.rb
+    ```
diff --git a/doc/date/calendars.rdoc b/doc/date/calendars.rdoc
new file mode 100644
index 0000000000..b8690841b1
--- /dev/null
+++ b/doc/date/calendars.rdoc
@@ -0,0 +1,62 @@
+== Julian and Gregorian Calendars
+
+The difference between the
+{Julian calendar}[https://en.wikipedia.org/wiki/Julian_calendar]
+and the
+{Gregorian calendar}[https://en.wikipedia.org/wiki/Gregorian_calendar]
+may matter to your program if it uses dates before the switchovers.
+
+- October 15, 1582.
+- September 14, 1752.
+
+A date will be different in the two calendars, in general.
+
+=== Different switchover dates
+
+The reasons for the difference are religious/political histories.
+
+- On October 15, 1582, several countries changed
+  from the Julian calendar to the Gregorian calendar;
+  these included Italy, Poland, Portugal, and Spain.
+  Other contries in the Western world retained the Julian calendar.
+- On September 14, 1752, most of the British empire
+  changed from the Julian calendar to the Gregorian calendar.
+
+When your code uses a date before these switchover dates,
+it will matter whether it considers the switchover date
+to be the earlier date or the later date (or neither).
+
+See also {a concrete example here}[rdoc-ref:DateTime@When+should+you+use+DateTime+and+when+should+you+use+Time-3F].
+
+=== Argument +start+
+
+Certain methods in class \Date handle differences in the
+{Julian and Gregorian calendars}[rdoc-ref:calendars.rdoc@Julian+and+Gregorian+Calendars]
+by accepting an optional argument +start+, whose value may be:
+
+- Date::ITALY (the default): the created date is Julian
+  if before October 15, 1582, Gregorian otherwise:
+
+      d = Date.new(1582, 10, 15)
+      d.prev_day.julian? # => true
+      d.julian?          # => false
+      d.gregorian?       # => true
+
+- Date::ENGLAND: the created date is Julian if before September 14, 1752,
+  Gregorian otherwise:
+
+    d = Date.new(1752, 9, 14, Date::ENGLAND)
+    d.prev_day.julian? # => true
+    d.julian?          # => false
+    d.gregorian?       # => true
+
+- Date::JULIAN: the created date is Julian regardless of its value:
+
+    d = Date.new(1582, 10, 15, Date::JULIAN)
+    d.julian? # => true
+
+- Date::GREGORIAN: the created date is Gregorian regardless of its value:
+
+    d = Date.new(1752, 9, 14, Date::GREGORIAN)
+    d.prev_day.gregorian? # => true
+
diff --git a/doc/documentation_guide.rdoc b/doc/documentation_guide.rdoc
deleted file mode 100644
index ae006752a2..0000000000
--- a/doc/documentation_guide.rdoc
+++ /dev/null
@@ -1,327 +0,0 @@
-= Documentation Guide
-
-This guide discusses recommendations for documenting
-classes, modules, and methods
-in the Ruby core and in the Ruby standard library.
-
-== Goal
-
-The goal of Ruby documentation is to impart the most important
-and relevant in the shortest time.
-The reader should be able to quickly understand the usefulness
-of the subject code and how to use it.
-
-Providing too little information is bad, but providing unimportant
-information or unnecessary examples is not good either.
-Use your judgment about what the user needs to know.
-
-== General Guidelines
-
-- Keep in mind that the reader may not be fluent in \English.
-- Write short declarative or imperative sentences.
-- Group sentences into (ideally short) paragraphs,
-  each covering a single topic.
-- Organize material with {headers}[rdoc-ref:RDoc::Markup@Headers].
-- Refer to authoritative and relevant sources using
-  {links}[rdoc-ref:RDoc::Markup@Links].
-- Use simple verb tenses: simple present, simple past, simple future.
-- Use simple sentence structure, not compound or complex structure.
-- Avoid:
-
-  - Excessive comma-separated phrases;
-    consider a {list}[rdoc-ref:RDoc::Markup@Simple+Lists].
-  - Idioms and culture-specific references.
-  - Overuse of headers.
-  - Using US-ASCII-incompatible characters in C source files;
-    see {Characters}[#label-Characters] below.
-
-=== Characters
-
-Use only US-ASCII-compatible characters in a C source file.
-(If you use other characters, the Ruby CI will gently let you know.)
-
-If want to put ASCII-incompatible characters into the documentation
-for a C-coded class, module, or method, there are workarounds
-involving new files <tt>doc/*.rdoc</tt>:
-
-- For class +Foo+ (defined in file <tt>foo.c</tt>),
-  create file <tt>doc/foo.rdoc</tt>, declare <tt>class Foo; end</tt>,
-  and place the class documentation above that declaration:
-
-    # :markup: ruby
-    # Documentation for class Foo goes here.
-    class Foo; end
-
-- Similarly, for module +Bar+ (defined in file <tt>bar.c</tt>,
-  create file <tt>doc/bar.rdoc</tt>, declare <tt>module Bar; end</tt>,
-  and place the module documentation above that declaration:
-
-    # :markup: ruby
-    # Documentation for module Bar goes here.
-    module Bar; end
-
-- For a method, things are different.
-  Documenting a method as above disables the "click to toggle source" feature
-  in the rendered documentation.
-
-  Therefore it's best to use file inclusion:
-
-  - Retain the call-seq in the C code.
-  - Use file inclusion (+:include:+) to include text from an .rdoc file.
-
-  Example:
-
-    /*
-     *  call-seq:
-     *    each_byte {|byte| ... } -> self
-     *    each_byte               -> enumerator
-     *
-     *  \:include: doc/string/each_byte.rdoc
-     *
-     */
-
-=== \RDoc
-
-Ruby is documented using RDoc.
-For information on \RDoc syntax and features, see the
-{RDoc Markup Reference}[rdoc-ref:RDoc::Markup@RDoc+Markup+Reference].
-
-=== Output from <tt>irb</tt>
-
-For code examples, consider using interactive Ruby,
-{irb}[https://ruby-doc.org/stdlib/libdoc/irb/rdoc/IRB.html].
-
-For a code example that includes +irb+ output,
-consider aligning <tt># => ...</tt> in successive lines.
-Alignment may sometimes aid readability:
-
-  a = [1, 2, 3] #=> [1, 2, 3]
-  a.shuffle!    #=> [2, 3, 1]
-  a             #=> [2, 3, 1]
-
-=== Headers
-
-Organize a long discussion with {headers}[rdoc-ref:RDoc::Markup@Headers].
-
-=== Blank Lines
-
-A blank line begins a new paragraph.
-
-A {code block}[rdoc-ref:RDoc::Markup@Paragraphs+and+Verbatim]
-or {list}[rdoc-ref:RDoc::Markup@Simple+Lists]
-should be preceded by and followed by a blank line.
-This is unnecessary for the HTML output, but helps in the +ri+ output.
-
-=== Auto-Linking
-
-In general, \RDoc's auto-linking should not be suppressed.
-For example, we should write +Array+, not <tt>\Array</tt>.
-
-We might consider whether to suppress when:
-
-- The word in question does not refer to a Ruby entity
-  (e.g., some uses of _Class_ or _English_).
-- The reference is to the current class document
-  (e.g., _Array_ in the documentation for class +Array+).
-- The same reference is repeated many times
-  (e.g., _RDoc_ on this page).
-
-== Documenting Classes and Modules
-
-The general structure of the class or module documentation should be:
-
-* Synopsis
-* Common uses, with examples
-* "What's Here" summary (optional)
-
-=== Synopsis
-
-The synopsis is a short description of what the class or module does
-and why the reader might want to use it.
-Avoid details in the synopsis.
-
-=== Common Uses
-
-Show common uses of the class or module.
-Depending on the class or module, this section may vary greatly
-in both length and complexity.
-
-=== What's Here Summary
-
-The documentation for a class or module may include a "What's Here" section.
-
-Guidelines:
-
-- The section title is <tt>What's Here</tt>.
-- Consider listing the parent class and any included modules; consider
-  {links}[rdoc-ref:RDoc::Markup@Links]
-  to their "What's Here" sections if those exist.
-- List methods as a bullet list:
-
-  - Begin each item with the method name, followed by a colon
-    and a short description.
-  - If the method has aliases, mention them in parentheses before the colon
-    (and do not list the aliases separately).
-  - Check the rendered documentation to determine whether \RDoc has recognized
-    the method and linked to it;  if not, manually insert a
-    {link}[rdoc-ref:RDoc::Markup@Links].
-
-- If there are numerous entries, consider grouping them into subsections with headers.
-- If there are more than a few such subsections,
-  consider adding a table of contents just below the main section title.
-
-== Documenting Methods
-
-=== General Structure
-
-The general structure of the method documentation should be:
-
-* Calling sequence (for methods written in C).
-* Synopsis (short description).
-* Details and examples.
-* Argument description (if necessary).
-* Corner cases and exceptions.
-* Aliases.
-* Related methods (optional).
-
-=== Calling Sequence (for methods written in C)
-
-For methods written in Ruby, \RDoc documents the calling sequence automatically.
-
-For methods written in C, \RDoc cannot determine what arguments
-the method accepts, so those need to be documented using \RDoc directive
-{:call-seq:}[rdoc-ref:RDoc::Markup@Method+arguments].
-
-Example:
-
-  *  call-seq:
-  *    array.count -> integer
-  *    array.count(obj) -> integer
-  *    array.count {|element| ... } -> integer
-
-When creating the <tt>call-seq</tt>, use the form
-
-  receiver_type.method_name(arguments) {|block_arguments|} -> return_type
-
-Omit the parentheses for cases where the method does not accept arguments,
-and omit the block for cases where a block is not accepted.
-
-In the cases where method can return multiple different types, separate the
-types with "or".  If the method can return any type, use "object".  If the
-method returns the receiver, use "self".
-
-In cases where the method accepts optional arguments, use a <tt>call-seq</tt>
-with an optional argument if the method has the same behavior when an argument
-is omitted as when the argument is passed with the default value.  For example,
-use:
-
-  *     obj.respond_to?(symbol, include_all=false) -> true or false
-
-Instead of:
-
-  *     obj.respond_to?(symbol) -> true or false
-  *     obj.respond_to?(symbol, include_all) -> true or false
-
-However, as shown above for <tt>Array#count</tt>, use separate lines if the
-behavior is different if the argument is omitted.
-
-Omit aliases from the call-seq, but mention them near the end (see below).
-
-
-A +call-seq+ block should have <tt>{|x| ... }</tt>, not <tt>{|x| block }</tt> or <tt>{|x| code }</tt>.
-
-A +call-seq+ output should:
-
-- Have +self+, not +receiver+ or +array+.
-- Begin with +new_+ if and only if the output object is a new instance
-  of the receiver's class, to emphasize that the output object is not +self+.
-
-=== Synopsis
-
-The synopsis comes next, and is a short description of what the
-method does and why you would want to use it.  Ideally, this
-is a single sentence, but for more complex methods it may require
-an entire paragraph.
-
-For <tt>Array#count</tt>, the synopsis is:
-
-  Returns a count of specified elements.
-
-This is great as it is short and descriptive.  Avoid documenting
-too much in the synopsis, stick to the most important information
-for the benefit of the reader.
-
-=== Details and Examples
-
-Most non-trivial methods benefit from examples, as well as details
-beyond what is given in the synopsis.  In the details and examples
-section, you can document how the method handles different types
-of arguments, and provides examples on proper usage.  In this
-section, focus on how to use the method properly, not on how the
-method handles improper arguments or corner cases.
-
-Not every behavior of a method requires an example.  If the method
-is documented to return +self+, you don't need to provide an example
-showing the return value is the same as the receiver.  If the method
-is documented to return +nil+, you don't need to provide an example
-showing that it returns +nil+.  If the details mention that for a
-certain argument type, an empty array is returned, you don't need
-to provide an example for that.
-
-Only add an example if it provides the user additional information,
-do not add an example if it provides the same information given
-in the synopsis or details.  The purpose of examples is not to prove
-what the details are stating.
-
-=== Argument Description (if necessary)
-
-For methods that require arguments, if not obvious and not explicitly
-mentioned in the details or implicitly shown in the examples, you can
-provide details about the types of arguments supported.  When discussing
-the types of arguments, use simple language even if less-precise, such
-as "level must be an integer", not "level must be an Integer-convertible
-object".  The vast majority of use will be with the expected type, not an
-argument that is explicitly convertible to the expected type, and
-documenting the difference is not important.
-
-For methods that take blocks, it can be useful to document the type of
-argument passed if it is not obvious, not explicitly mentioned in the
-details, and not implicitly shown in the examples.
-
-If there is more than one argument or block argument, use a
-{labeled list}[rdoc-ref:RDoc::Markup@Labeled+Lists]}
-
-=== Corner Cases and Exceptions
-
-For corner cases of methods, such as atypical usage, briefly mention
-the behavior, but do not provide any examples.
-
-Only document exceptions raised if they are not obvious.  For example,
-if you have stated earlier than an argument type must be an integer,
-you do not need to document that a \TypeError is raised if a non-integer
-is passed.  Do not provide examples of exceptions being raised unless
-that is a common case, such as \Hash#fetch raising a \KeyError.
-
-=== Aliases
-
-Mention aliases in the form
-
-  Array#find_index is an alias for Array#index.
-
-=== Related Methods (optional)
-
-In some cases, it is useful to document which methods are related to
-the current method.  For example, documentation for \Hash#[] might
-mention \Hash#fetch as a related method, and \Hash#merge might mention
-\Hash#merge! as a related method.  Consider which methods may be related
-to the current method, and if you think the reader would benefit it,
-at the end of the method documentation, add a line starting with
-"Related: " (e.g. "Related: #fetch").  Don't list more than three
-related methods. If you think more than three methods are related,
-pick the three you think are most important and list those three.
-
-=== Methods Accepting Multiple Argument Types
-
-For methods that accept multiple argument types, in some cases it can
-be useful to document the different argument types separately.  It's
-best to use a separate paragraph for each case you are discussing.
diff --git a/doc/encodings.rdoc b/doc/encodings.rdoc
index c61ab11e9a..1f3c54d740 100644
--- a/doc/encodings.rdoc
+++ b/doc/encodings.rdoc
@@ -467,12 +467,13 @@ These keyword-value pairs specify encoding options:
     with a carriage-return character (<tt>"\r"</tt>).
   - <tt>:crlf_newline: true</tt>: Replace each line-feed character (<tt>"\n"</tt>)
     with a carriage-return/line-feed string (<tt>"\r\n"</tt>).
-  - <tt>:universal_newline: true</tt>: Replace each carriage-return/line-feed string
+  - <tt>:universal_newline: true</tt>: Replace each carriage-return
+    character (<tt>"\r"</tt>) and each carriage-return/line-feed string
     (<tt>"\r\n"</tt>) with a line-feed character (<tt>"\n"</tt>).
 
   Examples:
 
-    s = "\n \r\n"                              # => "\n \r\n"
-    s.encode('ASCII', cr_newline: true)        # => "\r \r\r"
-    s.encode('ASCII', crlf_newline: true)      # => "\r\n \r\r\n"
-    s.encode('ASCII', universal_newline: true) # => "\n \n"
+    s = "\n \r \r\n"                           # => "\n \r \r\n"
+    s.encode('ASCII', cr_newline: true)        # => "\r \r \r\r"
+    s.encode('ASCII', crlf_newline: true)      # => "\r\n \r \r\r\n"
+    s.encode('ASCII', universal_newline: true) # => "\n \n \n"
diff --git a/doc/examples/files.rdoc b/doc/examples/files.rdoc
new file mode 100644
index 0000000000..f736132770
--- /dev/null
+++ b/doc/examples/files.rdoc
@@ -0,0 +1,26 @@
+# English text with newlines.
+text = <<~EOT
+  First line
+  Second line
+
+  Fourth line
+  Fifth line
+EOT
+
+# Russian text.
+russian = "\u{442 435 441 442}" # => "те�т"
+
+# Binary data.
+data = "\u9990\u9991\u9992\u9993\u9994"
+
+# Text file.
+File.write('t.txt', text)
+
+# File with Russian text.
+File.write('t.rus', russian)
+
+# File with binary data.
+f = File.new('t.dat', 'wb:UTF-16')
+f.write(data)
+f.close
+
diff --git a/doc/extension.ja.rdoc b/doc/extension.ja.rdoc
index dbe814560e..93f5753cd1 100644
--- a/doc/extension.ja.rdoc
+++ b/doc/extension.ja.rdoc
@@ -1066,6 +1066,20 @@ Rubyã�®ã‚½ãƒ¼ã‚¹ã�¯ã�„ã��ã�¤ã�‹ã�«åˆ†é¡žã�™ã‚‹ã�“ã�¨ã�Œå‡ºæ�¥ã�¾ã�™ï¼Žã�“ã�®ã�†ã
 ����．�れら�ソース�今���説明���ん��解��る�
 ����．
 
+=== Ruby�ヘッダファイル
+
+<tt>$repo_root/include/ruby</tt>以下����<tt>make
+install</tt>�インストール�れ��．拡張ライブラリ�ら�，
+<tt>#include <ruby.h></tt>�インクルード�る必���り��．
++rbimpl_+，+RBIMPL_+�プレフィックス�付��実装�詳細���
+�シンボルを除�，����シンボル�公開API��．
+
+拡張ライブラリ�直接インクルード��る��，
+<tt>$repo_root/include/ruby/*.h</tt>���，対応�る
+<tt>HAVE_RUBY_*_H</tt>マクロ�
+<tt>$repo_root/include/ruby.h</tt>ヘッダー�定義�れ��るも
+���．
+
 === Ruby言語�コア
 
 class.c    :: クラス�モジュール
@@ -1681,6 +1695,9 @@ HAVE_RUBY_*_H ::
   を�味�る．����，HAVE_RUBY_ST_H �定義�れ��る場��
   ��る st.h ���� ruby/st.h を使用�る．
 
+  �れら�マクロ�対応�るヘッダーファイル�，拡張ライブラリ
+  �ら直接インクルード��もよ�．
+
 RB_EVENT_HOOKS_HAVE_CALLBACK_DATA ::
 
   rb_add_event_hook() �フック関数�渡� data を第3引数���
diff --git a/doc/extension.rdoc b/doc/extension.rdoc
index 01bbcd816b..ad9ae641d2 100644
--- a/doc/extension.rdoc
+++ b/doc/extension.rdoc
@@ -1055,9 +1055,9 @@ All symbols are public API with the exception of symbols prefixed with
 +rbimpl_+ or +RBIMPL_+. They are implementation details and shouldn't
 be used by C extensions.
 
-Only <tt>$repo_root/include/ruby/*.h</tt> are allowed to be <tt>#include</tt>-d
-by C extensions. Files under <tt>$repo_root/include/ruby/internal</tt>
-should not be <tt>#include</tt>-d directly.
+Only <tt>$repo_root/include/ruby/*.h</tt> whose corresponding macros
+are defined in the <tt>$repo_root/include/ruby.h</tt> header are
+allowed to be <tt>#include</tt>-d by C extensions.
 
 Header files under <tt>$repo_root/internal/</tt> or directly under the
 root <tt>$repo_root/*.h</tt> are not make-installed.
@@ -1932,6 +1932,9 @@ HAVE_RUBY_*_H ::
   instance, when HAVE_RUBY_ST_H is defined you should use ruby/st.h not
   mere st.h.
 
+  Header files corresponding to these macros may be <tt>#include</tt>
+  directly from extension libraries.
+
 RB_EVENT_HOOKS_HAVE_CALLBACK_DATA ::
 
   Means that rb_add_event_hook() takes the third argument `data', to be
diff --git a/doc/format_specifications.rdoc b/doc/format_specifications.rdoc
new file mode 100644
index 0000000000..e589524f27
--- /dev/null
+++ b/doc/format_specifications.rdoc
@@ -0,0 +1,348 @@
+== Format Specifications
+
+Several Ruby core classes have instance method +printf+ or +sprintf+:
+
+- ARGF#printf
+- IO#printf
+- Kernel#printf
+- Kernel#sprintf
+
+Each of these methods takes:
+
+- Argument +format_string+, which has zero or more
+  embedded _format_ _specifications_ (see below).
+- Arguments <tt>*arguments</tt>, which are zero or more objects to be formatted.
+
+Each of these methods prints or returns the string
+resulting from replacing each
+format specification embedded in +format_string+ with a string form
+of the corresponding argument among +arguments+.
+
+A simple example:
+
+  sprintf('Name: %s; value: %d', 'Foo', 0) # => "Name: Foo; value: 0"
+
+A format specification has the form:
+
+  %[flags][width][.precision]type
+
+It consists of:
+
+- A leading percent character.
+- Zero or more _flags_ (each is a character).
+- An optional _width_ _specifier_ (an integer).
+- An optional _precision_ _specifier_ (a period followed by a non-negative integer).
+- A _type_ _specifier_ (a character).
+
+Except for the leading percent character,
+the only required part is the type specifier, so we begin with that.
+
+=== Type Specifiers
+
+This section provides a brief explanation of each type specifier.
+The links lead to the details and examples.
+
+==== \Integer Type Specifiers
+
+- +b+ or +B+: Format +argument+ as a binary integer.
+  See {Specifiers b and B}[rdoc-ref:format_specifications.rdoc@Specifiers+b+and+B].
+- +d+, +i+, or +u+ (all are identical):
+  Format +argument+ as a decimal integer.
+  See {Specifier d}[rdoc-ref:format_specifications.rdoc@Specifier+d].
+- +o+: Format +argument+ as an octal integer.
+  See {Specifier o}[rdoc-ref:format_specifications.rdoc@Specifier+o].
+- +x+ or +X+: Format +argument+ as a hexadecimal integer.
+  See {Specifiers x and X}[rdoc-ref:format_specifications.rdoc@Specifiers+x+and+X].
+
+==== Floating-Point Type Specifiers
+
+- +a+ or +A+: Format +argument+ as hexadecimal floating-point number.
+  See {Specifiers a and A}[rdoc-ref:format_specifications.rdoc@Specifiers+a+and+A].
+- +e+ or +E+: Format +argument+ in scientific notation.
+  See {Specifiers e and E}[rdoc-ref:format_specifications.rdoc@Specifiers+e+and+E].
+- +f+: Format +argument+ as a decimal floating-point number.
+  See {Specifier f}[rdoc-ref:format_specifications.rdoc@Specifier+f].
+- +g+ or +G+: Format +argument+ in a "general" format.
+  See {Specifiers g and G}[rdoc-ref:format_specifications.rdoc@Specifiers+g+and+G].
+
+==== Other Type Specifiers
+
+- +c+: Format +argument+ as a character.
+  See {Specifier c}[rdoc-ref:format_specifications.rdoc@Specifier+c].
+- +p+: Format +argument+ as a string via <tt>argument.inspect</tt>.
+  See {Specifier p}[rdoc-ref:format_specifications.rdoc@Specifier+p].
+- +s+: Format +argument+ as a string via <tt>argument.to_s</tt>.
+  See {Specifier s}[rdoc-ref:format_specifications.rdoc@Specifier+s].
+- <tt>%</tt>: Format +argument+ (<tt>'%'</tt>) as a single percent character.
+  See {Specifier %}[rdoc-ref:format_specifications.rdoc@Specifier+-25].
+
+=== Flags
+
+The effect of a flag may vary greatly among type specifiers.
+These remarks are general in nature.
+See {type-specific details}[rdoc-ref:format_specifications.rdoc@Type+Specifier+Details+and+Examples].
+
+Multiple flags may be given with single type specifier;
+order does not matter.
+
+==== <tt>' '</tt> Flag
+
+Insert a space before a non-negative number:
+
+  sprintf('%d', 10)  # => "10"
+  sprintf('% d', 10) # => " 10"
+
+Insert a minus sign for negative value:
+
+  sprintf('%d', -10)  # => "-10"
+  sprintf('% d', -10) # => "-10"
+
+==== <tt>'#'</tt> Flag
+
+Use an alternate format; varies among types:
+
+  sprintf('%x', 100)  # => "64"
+  sprintf('%#x', 100) # => "0x64"
+
+==== <tt>'+'</tt> Flag
+
+Add a leading plus sign for a non-negative number:
+
+  sprintf('%x', 100)  # => "64"
+  sprintf('%+x', 100) # => "+64"
+
+==== <tt>'-'</tt> Flag
+
+Left justify the value in its field:
+
+  sprintf('%6d', 100)  # => "   100"
+  sprintf('%-6d', 100) # => "100   "
+
+==== <tt>'0'</tt> Flag
+
+Left-pad with zeros instead of spaces:
+
+  sprintf('%6d', 100)  # => "   100"
+  sprintf('%06d', 100) # => "000100"
+
+==== <tt>'*'</tt> Flag
+
+Use the next argument as the field width:
+
+  sprintf('%d', 20, 14)  # => "20"
+  sprintf('%*d', 20, 14) # => "                  14"
+
+==== <tt>'n$'</tt> Flag
+
+Format the (1-based) <tt>n</tt>th argument into this field:
+
+    sprintf("%s %s", 'world', 'hello')     # => "world hello"
+    sprintf("%2$s %1$s", 'world', 'hello') # => "hello world"
+
+=== Width Specifier
+
+In general, a width specifier determines the minimum width (in characters)
+of the formatted field:
+
+  sprintf('%10d', 100)  # => "       100"
+
+  # Left-justify if negative.
+  sprintf('%-10d', 100) # => "100       "
+
+  # Ignore if too small.
+  sprintf('%1d', 100)   # => "100"
+
+=== Precision Specifier
+
+A precision specifier is a decimal point followed by zero or more
+decimal digits.
+
+For integer type specifiers, the precision specifies the minimum number of
+digits to be written. If the precision is shorter than the integer, the result is
+padded with leading zeros. There is no modification or truncation of the result
+if the integer is longer than the precision:
+
+  sprintf('%.3d', 1)    # => "001"
+  sprintf('%.3d', 1000) # => "1000"
+
+  # If the precision is 0 and the value is 0, nothing is written
+  sprintf('%.d', 0)  # => ""
+  sprintf('%.0d', 0) # => ""
+
+For the +a+/+A+, +e+/+E+, +f+/+F+ specifiers, the precision specifies
+the number of digits after the decimal point to be written:
+
+  sprintf('%.2f', 3.14159)  # => "3.14"
+  sprintf('%.10f', 3.14159) # => "3.1415900000"
+
+  # With no precision specifier, defaults to 6-digit precision.
+  sprintf('%f', 3.14159)    # => "3.141590"
+
+For the +g+/+G+ specifiers, the precision specifies
+the number of significant digits to be written:
+
+  sprintf('%.2g', 123.45)  # => "1.2e+02"
+  sprintf('%.3g', 123.45)  # => "123"
+  sprintf('%.10g', 123.45) # =>  "123.45"
+
+  # With no precision specifier, defaults to 6 significant digits.
+  sprintf('%g', 123.456789) # => "123.457"
+
+For the +s+, +p+ specifiers, the precision specifies
+the number of characters to write:
+
+  sprintf('%s', Time.now)    # => "2022-05-04 11:59:16 -0400"
+  sprintf('%.10s', Time.now) # => "2022-05-04"
+
+=== Type Specifier Details and Examples
+
+==== Specifiers +a+ and +A+
+
+Format +argument+ as hexadecimal floating-point number:
+
+  sprintf('%a', 3.14159)   # => "0x1.921f9f01b866ep+1"
+  sprintf('%a', -3.14159)  # => "-0x1.921f9f01b866ep+1"
+  sprintf('%a', 4096)      # => "0x1p+12"
+  sprintf('%a', -4096)     # => "-0x1p+12"
+
+  # Capital 'A' means that alphabetical characters are printed in upper case.
+  sprintf('%A', 4096)      # => "0X1P+12"
+  sprintf('%A', -4096)     # => "-0X1P+12"
+
+==== Specifiers +b+ and +B+
+
+The two specifiers +b+ and +B+ behave identically
+except when flag <tt>'#'</tt>+ is used.
+
+Format +argument+ as a binary integer:
+
+  sprintf('%b', 1)  # => "1"
+  sprintf('%b', 4)  # => "100"
+
+  # Prefix '..' for negative value.
+  sprintf('%b', -4) # => "..100"
+
+  # Alternate format.
+  sprintf('%#b', 4)  # => "0b100"
+  sprintf('%#B', 4)  # => "0B100"
+
+==== Specifier +c+
+
+Format +argument+ as a single character:
+
+  sprintf('%c', 'A') # => "A"
+  sprintf('%c', 65)  # => "A"
+
+==== Specifier +d+
+
+Format +argument+ as a decimal integer:
+
+  sprintf('%d', 100)  # => "100"
+  sprintf('%d', -100) # => "-100"
+
+Flag <tt>'#'</tt> does not apply.
+
+==== Specifiers +e+ and +E+
+
+Format +argument+ in
+{scientific notation}[https://en.wikipedia.org/wiki/Scientific_notation]:
+
+  sprintf('%e', 3.14159)  # => "3.141590e+00"
+  sprintf('%E', -3.14159) # => "-3.141590E+00"
+
+==== Specifier +f+
+
+Format +argument+ as a floating-point number:
+
+  sprintf('%f', 3.14159)  # => "3.141590"
+  sprintf('%f', -3.14159) # => "-3.141590"
+
+Flag <tt>'#'</tt> does not apply.
+
+==== Specifiers +g+ and +G+
+
+Format +argument+ using exponential form (+e+/+E+ specifier)
+if the exponent is less than -4 or greater than or equal to the precision.
+Otherwise format +argument+ using floating-point form (+f+ specifier):
+
+  sprintf('%g', 100)  # => "100"
+  sprintf('%g', 100.0)  # => "100"
+  sprintf('%g', 3.14159)  # => "3.14159"
+  sprintf('%g', 100000000000)  # => "1e+11"
+  sprintf('%g', 0.000000000001)  # => "1e-12"
+
+  # Capital 'G' means use capital 'E'.
+  sprintf('%G', 100000000000)  # => "1E+11"
+  sprintf('%G', 0.000000000001)  # => "1E-12"
+
+  # Alternate format.
+  sprintf('%#g', 100000000000)  # => "1.00000e+11"
+  sprintf('%#g', 0.000000000001)  # => "1.00000e-12"
+  sprintf('%#G', 100000000000)  # => "1.00000E+11"
+  sprintf('%#G', 0.000000000001)  # => "1.00000E-12"
+
+==== Specifier +o+
+
+Format +argument+ as an octal integer.
+If +argument+ is negative, it will be formatted as a two's complement
+prefixed with +..7+:
+
+  sprintf('%o', 16)   # => "20"
+
+  # Prefix '..7' for negative value.
+  sprintf('%o', -16)  # => "..760"
+
+  # Prefix zero for alternate format if positive.
+  sprintf('%#o', 16)  # => "020"
+  sprintf('%#o', -16) # => "..760"
+
+==== Specifier +p+
+
+Format +argument+ as a string via <tt>argument.inspect</tt>:
+
+  t = Time.now
+  sprintf('%p', t)   # => "2022-05-01 13:42:07.1645683 -0500"
+
+==== Specifier +s+
+
+Format +argument+ as a string via <tt>argument.to_s</tt>:
+
+  t = Time.now
+  sprintf('%s', t) # => "2022-05-01 13:42:07 -0500"
+
+Flag <tt>'#'</tt> does not apply.
+
+==== Specifiers +x+ and +X+
+
+Format +argument+ as a hexadecimal integer.
+If +argument+ is negative, it will be formatted as a two's complement
+prefixed with +..f+:
+
+  sprintf('%x', 100)   # => "64"
+
+  # Prefix '..f' for negative value.
+  sprintf('%x', -100)  # => "..f9c"
+
+  # Use alternate format.
+  sprintf('%#x', 100)  # => "0x64"
+
+  # Alternate format for negative value.
+  sprintf('%#x', -100) # => "0x..f9c"
+
+==== Specifier <tt>%</tt>
+
+Format +argument+ (<tt>'%'</tt>) as a single percent character:
+
+  sprintf('%d %%', 100) # => "100 %"
+
+Flags do not apply.
+
+=== Reference by Name
+
+For more complex formatting, Ruby supports a reference by name.
+%<name>s style uses format style, but %{name} style doesn't.
+
+Examples:
+
+  sprintf("%<foo>d : %<bar>f", { :foo => 1, :bar => 2 }) # => 1 : 2.000000
+  sprintf("%{foo}f", { :foo => 1 })                      # => "1f"
diff --git a/doc/hacking.md b/doc/hacking.md
deleted file mode 100644
index e441a40554..0000000000
--- a/doc/hacking.md
+++ /dev/null
@@ -1,104 +0,0 @@
-# Ruby Hacking Guide
-
-This document gives  some helpful instructions which  should make your
-experience as a Ruby core developer easier.
-
-## Setup
-
-### Make
-
-It's common to want to compile things as quickly as possible. Ensuring
-`make`  has the  right `--jobs`  flag will  ensure all  processors are
-utilized when building  software projects To do  this effectively, you
-can set `MAKEFLAGS` in your shell configuration/profile:
-
-``` shell
-# On macOS with Fish shell:
-export MAKEFLAGS="--jobs "(sysctl -n hw.ncpu)
-
-# On macOS with Bash/ZSH shell:
-export MAKEFLAGS="--jobs $(sysctl -n hw.ncpu)"
-
-# On Linux with Fish shell:
-export MAKEFLAGS="--jobs "(nproc)
-
-# On Linux with Bash/ZSH shell:
-export MAKEFLAGS="--jobs $(nproc)"
-```
-
-## Configure Ruby
-
-It's generally advisable to use a build directory.
-
-``` shell
-./autogen.sh
-mkdir build
-cd build
-../configure --prefix $HOME/.rubies/ruby-head
-make install
-```
-
-### Without Documentation
-
-If you  are frequently  building Ruby,  this will  reduce the  time it
-takes to `make install`.
-
-``` shell
-../configure --disable-install-doc
-```
-
-## Running Ruby
-
-### Run Local Test Script
-
-You can create  a file in the Ruby source  root called `test.rb`.  You
-can build `miniruby` and execute this script:
-
-``` shell
-make run
-```
-
-If  you want  more  of the  standard library,  you  can use  `runruby`
-instead of `run`.
-
-## Running Tests
-
-You can run the following tests at once:
-
-``` shell
-make check
-```
-
-### Run Bootstrap Tests
-
-There are  a set of tests  in `bootstraptest/` which cover  most basic
-features of the core Ruby language.
-
-``` shell
-make test
-```
-
-### Run Extensive Tests
-
-There  are extensive  tests in  `test/` which  cover a  wide range  of
-features of the Ruby core language.
-
-``` shell
-make test-all
-```
-
-You can run specific tests by specifying their path:
-
-``` shell
-make test-all TESTS=../test/fiber/test_io.rb
-```
-
-### Run Ruby Spec Suite Tests
-
-The [Ruby Spec Suite](https://github.com/ruby/spec/) is a test suite
-that aims to provide an executable description for the behavior of the
-language.
-
-``` shell
-make test-spec
-```
diff --git a/doc/implicit_conversion.rdoc b/doc/implicit_conversion.rdoc
index 0c2a1d4971..ba15fa4bf4 100644
--- a/doc/implicit_conversion.rdoc
+++ b/doc/implicit_conversion.rdoc
@@ -2,6 +2,7 @@
 
 Some Ruby methods accept one or more objects
 that can be either:
+
 * <i>Of a given class</i>, and so accepted as is.
 * <i>Implicitly convertible to that class</i>, in which case
   the called method converts the object.
@@ -17,10 +18,15 @@ a specific conversion method:
 === Array-Convertible Objects
 
 An <i>Array-convertible object</i> is an object that:
+
 * Has instance method +to_ary+.
 * The method accepts no arguments.
 * The method returns an object +obj+ for which <tt>obj.kind_of?(Array)</tt> returns +true+.
 
+The Ruby core class that satisfies these requirements is:
+
+* Array
+
 The examples in this section use method <tt>Array#replace</tt>,
 which accepts an Array-convertible argument.
 
@@ -66,10 +72,15 @@ This class is not Array-convertible (method +to_ary+ returns non-Array):
 === Hash-Convertible Objects
 
 A <i>Hash-convertible object</i> is an object that:
+
 * Has instance method +to_hash+.
 * The method accepts no arguments.
 * The method returns an object +obj+ for which <tt>obj.kind_of?(Hash)</tt> returns +true+.
 
+The Ruby core class that satisfies these requirements is:
+
+* Hash
+
 The examples in this section use method <tt>Hash#merge</tt>,
 which accepts a Hash-convertible argument.
 
@@ -115,10 +126,18 @@ This class is not Hash-convertible (method +to_hash+ returns non-Hash):
 === Integer-Convertible Objects
 
 An <i>Integer-convertible object</i> is an object that:
+
 * Has instance method +to_int+.
 * The method accepts no arguments.
 * The method returns an object +obj+ for which <tt>obj.kind_of?(Integer)</tt> returns +true+.
 
+The Ruby core classes that satisfy these requirements are:
+
+* Integer
+* Float
+* Complex
+* Rational
+
 The examples in this section use method <tt>Array.new</tt>,
 which accepts an Integer-convertible argument.
 
@@ -159,6 +178,10 @@ A <i>String-convertible object</i> is an object that:
 * The method accepts no arguments.
 * The method returns an object +obj+ for which <tt>obj.kind_of?(String)</tt> returns +true+.
 
+The Ruby core class that satisfies these requirements is:
+
+* String
+
 The examples in this section use method <tt>String::new</tt>,
 which accepts a String-convertible argument.
 
diff --git a/doc/maintainers.rdoc b/doc/maintainers.rdoc
index ada0fcf325..7e0c35194f 100644
--- a/doc/maintainers.rdoc
+++ b/doc/maintainers.rdoc
@@ -119,6 +119,10 @@ Yukihiro Matsumoto (matz)
   Masatoshi SEKI (seki), Takashi Kokubun (k0kubun)
   https://github.com/ruby/erb
   https://rubygems.org/gems/erb
+[lib/error_highlight.rb, lib/error_highlight/*]
+  Yusuke Endoh (mame)
+  https://github.com/ruby/error_highlight
+  https://rubygems.org/gems/error_highlight
 [lib/fileutils.rb]
   _unmaintained_
   https://github.com/ruby/fileutils
@@ -209,6 +213,10 @@ Yukihiro Matsumoto (matz)
   Eric Hodel (drbrain), Hiroshi SHIBATA (hsbt)
   https://github.com/ruby/rdoc
   https://rubygems.org/gems/rdoc
+[lib/readline.rb]
+  aycabta
+  https://github.com/ruby/readline
+  https://rubygems.org/gems/readline
 [lib/reline.rb, lib/reline/*]
   aycabta
   https://github.com/ruby/reline
diff --git a/doc/make_cheatsheet.md b/doc/make_cheatsheet.md
deleted file mode 100644
index f679f69cb3..0000000000
--- a/doc/make_cheatsheet.md
+++ /dev/null
@@ -1,124 +0,0 @@
-# How to use "configure" and "make" commands for Ruby
-
-This is for developers of Ruby.
-If you are a user of Ruby, please see README.md.
-
-## In-place build
-
-```
-$ ./autogen.sh
-$ ./configure --prefix=$PWD/local
-$ make
-$ make install
-$ ./local/bin/ruby -e 'puts "Hello"'
-Hello
-```
-
-## Out-of-place build
-
-```
-$ ./autogen.sh
-$ mkdir ../ruby-build
-$ cd ../ruby-build
-$ ../ruby-src/configure --prefix=$PWD/local
-$ make
-$ make install
-$ ./local/bin/ruby -e 'puts "Hello"'
-Hello
-```
-
-## How to run the whole test suite
-
-```
-$ make check
-```
-
-It runs (about) four test suites:
-
-* `make test` (a test suite for the interpreter core)
-* `make test-all` (for all builtin classes and libraries)
-* `make test-spec` (a conformance test suite for Ruby implementations)
-* `make test-bundler` (a test suite for the bundler examples)
-
-## How to run the test suite with log
-
-```
-$ make test OPTS=-v
-
-$ make test-all TESTS=-v
-
-$ make test-spec MSPECOPT=-Vfs
-```
-
-## How to run a part of the test suite
-
-### Runs a directory
-```
-$ make test-all TESTS=test/rubygems
-$ make test-all TESTS=rubygems
-```
-
-### Runs a file
-```
-$ make test-all TESTS=test/ruby/test_foo.rb
-$ make test-all TESTS=ruby/foo
-```
-
-### Runs a test whose name includes test_bar
-```
-$ make test-all TESTS="test/ruby/test_foo.rb -n /test_bar/"
-```
-
-### Runs a file or directory with GNU make
-```
-$ make test/ruby/test_foo.rb
-$ make test/ruby/test_foo.rb TESTOPTS="-n /test_bar/"
-```
-
-### Runs a ruby-spec directory
-```
-$ make test-spec MSPECOPT=spec/ruby/core/foo
-```
-
-### Runs a ruby-spec file
-```
-$ make test-spec MSPECOPT=spec/ruby/core/foo/bar_spec.rb
-```
-
-### Runs a ruby-spec file or directory with GNU make
-```
-$ make spec/ruby/core/foo/bar_spec.rb
-```
-
-### Runs a bundler spec file
-```
-$ make test-bundler BUNDLER_SPECS=commands/exec_spec.rb:58
-```
-
-## How to measure coverage of C and Ruby code
-
-You need to be able to use gcc (gcov) and lcov visualizer.
-
-```
-$ ./autogen.sh
-$ ./configure --enable-gcov
-$ make
-$ make update-coverage
-$ rm -f test-coverage.dat
-$ make test-all COVERAGE=true
-$ make lcov
-$ open lcov-out/index.html
-```
-
-If you need only C code coverage, you can remove `COVERAGE=true` from the above process.
-You can also use `gcov` command directly to get per-file coverage.
-
-If you need only Ruby code coverage, you can remove `--enable-gcov`.
-Note that `test-coverage.dat` accumulates all runs of `make test-all`.
-Make sure that you remove the file if you want to measure one test run.
-
-You can see the coverage result of CI: https://rubyci.org/coverage
-
-## How to benchmark
-
-see https://github.com/ruby/ruby/tree/master/benchmark#make-benchmark
diff --git a/doc/matchdata/begin.rdoc b/doc/matchdata/begin.rdoc
new file mode 100644
index 0000000000..8046dd9d55
--- /dev/null
+++ b/doc/matchdata/begin.rdoc
@@ -0,0 +1,30 @@
+Returns the offset (in characters) of the beginning of the specified match.
+
+When non-negative integer argument +n+ is given,
+returns the offset of the beginning of the <tt>n</tt>th match:
+
+  m = /(.)(.)(\d+)(\d)/.match("THX1138.")
+  # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
+  m[0]       # => "HX1138"
+  m.begin(0) # => 1
+  m[3]       # => "113"
+  m.begin(3) # => 3
+
+  m = /(т)(е)(�)/.match('те�т')
+  # => #<MatchData "те�" 1:"т" 2:"е" 3:"�">
+  m[0]       # => "те�"
+  m.begin(0) # => 0
+  m[3]       # => "�"
+  m.begin(3) # => 2
+
+When string or symbol argument +name+ is given,
+returns the offset of the beginning for the named match:
+
+  m = /(?<foo>.)(.)(?<bar>.)/.match("hoge")
+  # => #<MatchData "hog" foo:"h" bar:"g">
+  m[:foo]        # => "h"
+  m.begin('foo') # => 0
+  m[:bar]        # => "g"
+  m.begin(:bar)  # => 2
+
+Related: MatchData#end, MatchData#offset, MatchData#byteoffset.
diff --git a/doc/matchdata/end.rdoc b/doc/matchdata/end.rdoc
new file mode 100644
index 0000000000..0209b2d2fc
--- /dev/null
+++ b/doc/matchdata/end.rdoc
@@ -0,0 +1,30 @@
+Returns the offset (in characters) of the end of the specified match.
+
+When non-negative integer argument +n+ is given,
+returns the offset of the end of the <tt>n</tt>th match:
+
+  m = /(.)(.)(\d+)(\d)/.match("THX1138.")
+  # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
+  m[0]     # => "HX1138"
+  m.end(0) # => 7
+  m[3]     # => "113"
+  m.end(3) # => 6
+
+  m = /(т)(е)(�)/.match('те�т')
+  # => #<MatchData "те�" 1:"т" 2:"е" 3:"�">
+  m[0]     # => "те�"
+  m.end(0) # => 3
+  m[3]     # => "�"
+  m.end(3) # => 3
+
+When string or symbol argument +name+ is given,
+returns the offset of the end for the named match:
+
+  m = /(?<foo>.)(.)(?<bar>.)/.match("hoge")
+  # => #<MatchData "hog" foo:"h" bar:"g">
+  m[:foo]      # => "h"
+  m.end('foo') # => 1
+  m[:bar]      # => "g"
+  m.end(:bar)  # => 3
+
+Related: MatchData#begin, MatchData#offset, MatchData#byteoffset.
diff --git a/doc/matchdata/offset.rdoc b/doc/matchdata/offset.rdoc
new file mode 100644
index 0000000000..0985316d76
--- /dev/null
+++ b/doc/matchdata/offset.rdoc
@@ -0,0 +1,31 @@
+Returns a 2-element array containing the beginning and ending
+offsets (in characters) of the specified match.
+
+When non-negative integer argument +n+ is given,
+returns the starting and ending offsets of the <tt>n</tt>th match:
+
+  m = /(.)(.)(\d+)(\d)/.match("THX1138.")
+  # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
+  m[0]        # => "HX1138"
+  m.offset(0) # => [1, 7]
+  m[3]        # => "113"
+  m.offset(3) # => [3, 6]
+
+  m = /(т)(е)(�)/.match('те�т')
+  # => #<MatchData "те�" 1:"т" 2:"е" 3:"�">
+  m[0]        # => "те�"
+  m.offset(0) # => [0, 3]
+  m[3]        # => "�"
+  m.offset(3) # => [2, 3]
+
+When string or symbol argument +name+ is given,
+returns the starting and ending offsets for the named match:
+
+  m = /(?<foo>.)(.)(?<bar>.)/.match("hoge")
+  # => #<MatchData "hog" foo:"h" bar:"g">
+  m[:foo]         # => "h"
+  m.offset('foo') # => [0, 1]
+  m[:bar]         # => "g"
+  m.offset(:bar)  # => [2, 3]
+
+Related: MatchData#byteoffset, MatchData#begin, MatchData#end.
diff --git a/doc/math/math.rdoc b/doc/math/math.rdoc
new file mode 100644
index 0000000000..7a89df951c
--- /dev/null
+++ b/doc/math/math.rdoc
@@ -0,0 +1,117 @@
+\Module \Math provides methods for basic trigonometric,
+logarithmic, and transcendental functions, and for extracting roots.
+
+You can write its constants and method calls thus:
+
+  Math::PI      # => 3.141592653589793
+  Math::E       # => 2.718281828459045
+  Math.sin(0.0) # => 0.0
+  Math.cos(0.0) # => 1.0
+
+If you include module \Math, you can write simpler forms:
+
+  include Math
+  PI       # => 3.141592653589793
+  E        # => 2.718281828459045
+  sin(0.0) # => 0.0
+  cos(0.0) # => 1.0
+
+For simplicity, the examples here assume:
+
+  include Math
+  INFINITY = Float::INFINITY
+
+The domains and ranges for the methods
+are denoted by open or closed intervals,
+using, respectively, parentheses or square brackets:
+
+- An open interval does not include the endpoints:
+
+    (-INFINITY, INFINITY)
+
+- A closed interval includes the endpoints:
+
+    [-1.0, 1.0]
+
+- A half-open interval includes one endpoint, but not the other:
+
+   [1.0, INFINITY)
+
+Many values returned by \Math methods are numerical approximations.
+This is because many such values are, in mathematics,
+of infinite precision, while in numerical computation
+the precision is finite.
+
+Thus, in mathematics, <i>cos(Ï€/2)</i> is exactly zero,
+but in our computation <tt>cos(PI/2)</tt> is a number very close to zero:
+
+  cos(PI/2) # => 6.123031769111886e-17
+
+For very large and very small returned values,
+we have added formatted numbers for clarity:
+
+  tan(PI/2)  # => 1.633123935319537e+16   # 16331239353195370.0
+  tan(PI)    # => -1.2246467991473532e-16 # -0.0000000000000001
+
+See class Float for the constants
+that affect Ruby's floating-point arithmetic.
+
+=== What's Here
+
+==== Trigonometric Functions
+
+- ::cos: Returns the cosine of the given argument.
+- ::sin: Returns the sine of the given argument.
+- ::tan: Returns the tangent of the given argument.
+
+==== Inverse Trigonometric Functions
+
+- ::acos: Returns the arc cosine of the given argument.
+- ::asin: Returns the arc sine of the given argument.
+- ::atan: Returns the arc tangent of the given argument.
+- ::atan2: Returns the arg tangent of two given arguments.
+
+==== Hyperbolic Trigonometric Functions
+
+- ::cosh: Returns the hyperbolic cosine of the given argument.
+- ::sinh: Returns the hyperbolic sine of the given argument.
+- ::tanh: Returns the hyperbolic tangent of the given argument.
+
+==== Inverse Hyperbolic Trigonometric Functions
+
+- ::acosh: Returns the inverse hyperbolic cosine of the given argument.
+- ::asinh: Returns the inverse hyperbolic sine of the given argument.
+- ::atanh: Returns the inverse hyperbolic tangent of the given argument.
+
+==== Exponentiation and Logarithmic Functions
+
+- ::exp: Returns the value of a given value raised to a given power.
+- ::log: Returns the logarithm of a given value in a given base.
+- ::log10: Returns the base 10 logarithm of the given argument.
+- ::log2: Returns the base 2 logarithm of the given argument.
+
+==== Fraction and Exponent Functions
+
+- ::frexp: Returns the fraction and exponent of the given argument.
+- ::ldexp: Returns the value for a given fraction and exponent.
+
+==== Root Functions
+
+- ::cbrt: Returns the cube root of the given argument.
+- ::sqrt: Returns the square root of the given argument.
+
+==== Error Functions
+
+- ::erf: Returns the value of the Gauss error function for the given argument.
+- ::erfc: Returns the value of the complementary error function
+  for the given argument.
+
+==== Gamma Functions
+
+- ::gamma: Returns the value of the gamma function for the given argument.
+- ::lgamma: Returns the value of the logarithmic gamma function
+  for the given argument.
+
+==== Hypotenuse Function
+
+- ::hypot: Returns <tt>sqrt(a**2 + b**2)</tt> for the given +a+ and +b+.
diff --git a/doc/mjit/mjit.md b/doc/mjit/mjit.md
new file mode 100644
index 0000000000..6f19ab3ea7
--- /dev/null
+++ b/doc/mjit/mjit.md
@@ -0,0 +1,39 @@
+# MJIT
+
+This document has some tips that might be useful when you work on MJIT.
+
+## Supported platforms
+
+The following platforms are either tested on CI or assumed to work.
+
+* OS: Linux, macOS
+* Arch: x86\_64, aarch64, arm64, i686, i386
+
+### Not supported
+
+The MJIT support for the following platforms is no longer maintained.
+
+* OS: Windows (mswin, MinGW), Solaris
+* Arch: SPARC, s390x
+
+## Developing MJIT
+
+### Bindgen
+
+If you see an "MJIT bindgen" GitHub Actions failure, please commit the `git diff` shown on the failed job.
+
+For doing the same thing locally, run `make mjit-bindgen` after installing libclang.
+macOS seems to have libclang by default. On Ubuntu, you can install it with `apt install libclang1`.
+
+### Always run make install
+
+Always run `make install` before running MJIT. It could easily cause a SEGV if you don't.
+MJIT looks for the installed header for security reasons.
+
+### --mjit-debug vs --mjit-debug=-ggdb3
+
+`--mjit-debug=[flags]` allows you to specify arbitrary flags while keeping other compiler flags like `-O3`,
+which is useful for profiling benchmarks.
+
+`--mjit-debug` alone, on the other hand, disables `-O3` and adds debug flags.
+If you're debugging MJIT, what you need to use is not `--mjit-debug=-ggdb3` but `--mjit-debug`.
diff --git a/doc/net-http/examples.rdoc b/doc/net-http/examples.rdoc
new file mode 100644
index 0000000000..c1366e7ad1
--- /dev/null
+++ b/doc/net-http/examples.rdoc
@@ -0,0 +1,31 @@
+Examples here assume that <tt>net/http</tt> has been required
+(which also requires +uri+):
+
+  require 'net/http'
+
+Many code examples here use these example websites:
+
+- https://jsonplaceholder.typicode.com.
+- http://example.com.
+
+Some examples also assume these variables:
+
+  uri = URI('https://jsonplaceholder.typicode.com/')
+  uri.freeze # Examples may not modify.
+  hostname = uri.hostname # => "jsonplaceholder.typicode.com"
+  path = uri.path         # => "/"
+  port = uri.port         # => 443
+
+So that example requests may be written as:
+
+  Net::HTTP.get(uri)
+  Net::HTTP.get(hostname, '/index.html')
+  Net::HTTP.start(hostname) do |http|
+    http.get('/todos/1')
+    http.get('/todos/2')
+  end
+
+An example that needs a modified URI first duplicates +uri+, then modifies the duplicate:
+
+  _uri = uri.dup
+  _uri.path = '/todos/1'
diff --git a/doc/net-http/included_getters.rdoc b/doc/net-http/included_getters.rdoc
new file mode 100644
index 0000000000..7ac327f4b4
--- /dev/null
+++ b/doc/net-http/included_getters.rdoc
@@ -0,0 +1,3 @@
+This class also includes (indirectly) module Net::HTTPHeader,
+which gives access to its
+{methods for getting headers}[rdoc-ref:Net::HTTPHeader@Getters].
diff --git a/doc/optparse/creates_option.rdoc b/doc/optparse/creates_option.rdoc
index ad52c6671b..ab672d5124 100644
--- a/doc/optparse/creates_option.rdoc
+++ b/doc/optparse/creates_option.rdoc
@@ -1,7 +1,7 @@
 Creates an option from the given parameters +params+.
-See {Parameters for New Options}[./option_params.rdoc].
+See {Parameters for New Options}[optparse/option_params.rdoc].
 
 The block, if given, is the handler for the created option.
 When the option is encountered during command-line parsing,
 the block is called with the argument given for the option, if any.
-See {Option Handlers}[./option_params.rdoc#label-Option+Handlers].
+See {Option Handlers}[optparse/option_params.rdoc#label-Option+Handlers].
diff --git a/doc/optparse/option_params.rdoc b/doc/optparse/option_params.rdoc
index b2e4e1a33c..ace2c4283f 100644
--- a/doc/optparse/option_params.rdoc
+++ b/doc/optparse/option_params.rdoc
@@ -418,7 +418,7 @@ A description parameter is any string parameter
 that is not recognized as an
 {option name}[#label-Option+Names] or a
 {terminator}[#label-Terminators];
-in other words, it does not begin with a hypnen.
+in other words, it does not begin with a hyphen.
 
 You may give any number of description parameters;
 each becomes a line in the text generated by option <tt>--help</tt>.
@@ -453,7 +453,7 @@ when the option is encountered.  The handler may be:
 
 ==== Handler Blocks
 
-An option hadler may be a block.
+An option handler may be a block.
 
 File +block.rb+ defines an option that has a handler block.
 
diff --git a/doc/optparse/tutorial.rdoc b/doc/optparse/tutorial.rdoc
index 19c86b93d8..b95089826d 100644
--- a/doc/optparse/tutorial.rdoc
+++ b/doc/optparse/tutorial.rdoc
@@ -657,7 +657,7 @@ Though you may never need to call it directly,
 here's the core method for defining an option:
 
 - \Method \OptionParser#make_switch accepts an array of parameters and a block.
-  See {Parameters for New Options}[./option_params.rdoc].
+  See {Parameters for New Options}[optparse/option_params.rdoc].
   This method is unlike others here in that it:
   - Accepts an <em>array of parameters</em>;
     others accept a <em>sequence of parameter arguments</em>.
diff --git a/doc/packed_data.rdoc b/doc/packed_data.rdoc
new file mode 100644
index 0000000000..ec13b24c69
--- /dev/null
+++ b/doc/packed_data.rdoc
@@ -0,0 +1,590 @@
+== Packed \Data
+
+Certain Ruby core methods deal with packing and unpacking data:
+
+- \Method Array#pack:
+  Formats each element in array +self+ into a binary string;
+  returns that string.
+- \Method String#unpack:
+  Extracts data from string +self+,
+  forming objects that become the elements of a new array;
+  returns that array.
+- \Method String#unpack1:
+  Does the same, but unpacks and returns only the first extracted object.
+
+Each of these methods accepts a string +template+,
+consisting of zero or more _directive_ characters,
+each followed by zero or more _modifier_ characters.
+
+Examples (directive <tt>'C'</tt> specifies 'unsigned character'):
+
+  [65].pack('C')      # => "A"  # One element, one directive.
+  [65, 66].pack('CC') # => "AB" # Two elements, two directives.
+  [65, 66].pack('C')  # => "A"  # Extra element is ignored.
+  [65].pack('')       # => ""   # No directives.
+  [65].pack('CC')               # Extra directive raises ArgumentError.
+
+  'A'.unpack('C')   # => [65]      # One character, one directive.
+  'AB'.unpack('CC') # => [65, 66]  # Two characters, two directives.
+  'AB'.unpack('C')  # => [65]      # Extra character is ignored.
+  'A'.unpack('CC')  # => [65, nil] # Extra directive generates nil.
+  'AB'.unpack('')   # => []        # No directives.
+
+The string +template+ may contain any mixture of valid directives
+(directive <tt>'c'</tt> specifies 'signed character'):
+
+  [65, -1].pack('cC')  # => "A\xFF"
+  "A\xFF".unpack('cC') # => [65, 255]
+
+The string +template+ may contain whitespace (which is ignored)
+and comments, each of which begins with character <tt>'#'</tt>
+and continues up to and including the next following newline:
+
+  [0,1].pack("  C  #foo \n  C  ")    # => "\x00\x01"
+  "\0\1".unpack("  C  #foo \n  C  ") # => [0, 1]
+
+Any directive may be followed by either of these modifiers:
+
+- <tt>'*'</tt> - The directive is to be applied as many times as needed:
+
+    [65, 66].pack('C*') # => "AB"
+    'AB'.unpack('C*')   # => [65, 66]
+
+- Integer +count+ - The directive is to be applied +count+ times:
+
+    [65, 66].pack('C2') # => "AB"
+    [65, 66].pack('C3') # Raises ArgumentError.
+    'AB'.unpack('C2')   # => [65, 66]
+    'AB'.unpack('C3')   # => [65, 66, nil]
+
+  Note: Directives in <tt>%w[A a Z m]</tt> use +count+ differently;
+  see {String Directives}[rdoc-ref:packed_data.rdoc@String+Directives].
+
+If elements don't fit the provided directive, only least significant bits are encoded:
+
+    [257].pack("C").unpack("C") # => [1]
+
+=== Packing \Method
+
+\Method Array#pack accepts optional keyword argument
++buffer+ that specifies the target string (instead of a new string):
+
+  [65, 66].pack('C*', buffer: 'foo') # => "fooAB"
+
+The method can accept a block:
+
+  # Packed string is passed to the block.
+  [65, 66].pack('C*') {|s| p s }    # => "AB"
+
+=== Unpacking Methods
+
+Methods String#unpack and String#unpack1 each accept
+an optional keyword argument +offset+ that specifies an offset
+into the string:
+
+  'ABC'.unpack('C*', offset: 1)  # => [66, 67]
+  'ABC'.unpack1('C*', offset: 1) # => 66
+
+Both methods can accept a block:
+
+  # Each unpacked object is passed to the block.
+  ret = []
+  "ABCD".unpack("C*") {|c| ret << c }
+  ret # => [65, 66, 67, 68]
+
+  # The single unpacked object is passed to the block.
+  'AB'.unpack1('C*') {|ele| p ele } # => 65
+
+=== \Integer Directives
+
+Each integer directive specifies the packing or unpacking
+for one element in the input or output array.
+
+==== 8-Bit \Integer Directives
+
+- <tt>'c'</tt> - 8-bit signed integer
+  (like C <tt>signed char</tt>):
+
+    [0, 1, 255].pack('c*')  # => "\x00\x01\xFF"
+    s = [0, 1, -1].pack('c*') # => "\x00\x01\xFF"
+    s.unpack('c*') # => [0, 1, -1]
+
+- <tt>'C'</tt> - 8-bit signed integer
+  (like C <tt>unsigned char</tt>):
+
+    [0, 1, 255].pack('C*')    # => "\x00\x01\xFF"
+    s = [0, 1, -1].pack('C*') # => "\x00\x01\xFF"
+    s.unpack('C*')            # => [0, 1, 255]
+
+==== 16-Bit \Integer Directives
+
+- <tt>'s'</tt> - 16-bit signed integer, native-endian
+  (like C <tt>int16_t</tt>):
+
+    [513, -514].pack('s*')      # => "\x01\x02\xFE\xFD"
+    s = [513, 65022].pack('s*') # => "\x01\x02\xFE\xFD"
+    s.unpack('s*')              # => [513, -514]
+
+- <tt>'S'</tt> - 16-bit unsigned integer, native-endian
+  (like C <tt>uint16_t</tt>):
+
+    [513, -514].pack('S*')      # => "\x01\x02\xFE\xFD"
+    s = [513, 65022].pack('S*') # => "\x01\x02\xFE\xFD"
+    s.unpack('S*')              # => [513, 65022]
+
+- <tt>'n'</tt> - 16-bit network integer, big-endian:
+
+    s = [0, 1, -1, 32767, -32768, 65535].pack('n*')
+    # => "\x00\x00\x00\x01\xFF\xFF\x7F\xFF\x80\x00\xFF\xFF"
+    s.unpack('n*')
+    # => [0, 1, 65535, 32767, 32768, 65535]
+
+- <tt>'v'</tt> - 16-bit VAX integer, little-endian:
+
+    s = [0, 1, -1, 32767, -32768, 65535].pack('v*')
+    # => "\x00\x00\x01\x00\xFF\xFF\xFF\x7F\x00\x80\xFF\xFF"
+    s.unpack('v*')
+    # => [0, 1, 65535, 32767, 32768, 65535]
+
+==== 32-Bit \Integer Directives
+
+- <tt>'l'</tt> - 32-bit signed integer, native-endian
+  (like C <tt>int32_t</tt>):
+
+    s = [67305985, -50462977].pack('l*')
+    # => "\x01\x02\x03\x04\xFF\xFE\xFD\xFC"
+    s.unpack('l*')
+    # => [67305985, -50462977]
+
+- <tt>'L'</tt> - 32-bit unsigned integer, native-endian
+  (like C <tt>uint32_t</tt>):
+
+    s = [67305985, 4244504319].pack('L*')
+    # => "\x01\x02\x03\x04\xFF\xFE\xFD\xFC"
+    s.unpack('L*')
+    # => [67305985, 4244504319]
+
+- <tt>'N'</tt> - 32-bit network integer, big-endian:
+
+    s = [0,1,-1].pack('N*')
+    # => "\x00\x00\x00\x00\x00\x00\x00\x01\xFF\xFF\xFF\xFF"
+    s.unpack('N*')
+    # => [0, 1, 4294967295]
+
+- <tt>'V'</tt> - 32-bit VAX integer, little-endian:
+
+    s = [0,1,-1].pack('V*')
+    # => "\x00\x00\x00\x00\x01\x00\x00\x00\xFF\xFF\xFF\xFF"
+    s.unpack('v*')
+    # => [0, 0, 1, 0, 65535, 65535]
+
+==== 64-Bit \Integer Directives
+
+- <tt>'q'</tt> - 64-bit signed integer, native-endian
+  (like C <tt>int64_t</tt>):
+
+    s = [578437695752307201, -506097522914230529].pack('q*')
+    # => "\x01\x02\x03\x04\x05\x06\a\b\xFF\xFE\xFD\xFC\xFB\xFA\xF9\xF8"
+    s.unpack('q*')
+    # => [578437695752307201, -506097522914230529]
+
+- <tt>'Q'</tt> - 64-bit unsigned integer, native-endian
+  (like C <tt>uint64_t</tt>):
+
+    s = [578437695752307201, 17940646550795321087].pack('Q*')
+    # => "\x01\x02\x03\x04\x05\x06\a\b\xFF\xFE\xFD\xFC\xFB\xFA\xF9\xF8"
+    s.unpack('Q*')
+    # => [578437695752307201, 17940646550795321087]
+
+==== Platform-Dependent \Integer Directives
+
+- <tt>'i'</tt> - Platform-dependent width signed integer,
+  native-endian (like C <tt>int</tt>):
+
+    s = [67305985, -50462977].pack('i*')
+    # => "\x01\x02\x03\x04\xFF\xFE\xFD\xFC"
+    s.unpack('i*')
+    # => [67305985, -50462977]
+
+- <tt>'I'</tt> - Platform-dependent width unsigned integer,
+  native-endian (like C <tt>unsigned int</tt>):
+
+    s = [67305985, -50462977].pack('I*')
+    # => "\x01\x02\x03\x04\xFF\xFE\xFD\xFC"
+    s.unpack('I*')
+    # => [67305985, 4244504319]
+
+==== Pointer Directives
+
+- <tt>'j'</tt> - 64-bit pointer-width signed integer,
+  native-endian (like C <tt>intptr_t</tt>):
+
+    s = [67305985, -50462977].pack('j*')
+    # => "\x01\x02\x03\x04\x00\x00\x00\x00\xFF\xFE\xFD\xFC\xFF\xFF\xFF\xFF"
+    s.unpack('j*')
+    # => [67305985, -50462977]
+
+- <tt>'j'</tt> - 64-bit pointer-width unsigned integer,
+  native-endian (like C <tt>uintptr_t</tt>):
+
+    s = [67305985, 4244504319].pack('J*')
+    # => "\x01\x02\x03\x04\x00\x00\x00\x00\xFF\xFE\xFD\xFC\x00\x00\x00\x00"
+    s.unpack('J*')
+    # => [67305985, 4244504319]
+
+==== Other \Integer Directives
+:
+- <tt>'U'</tt> - UTF-8 character:
+
+    s = [4194304].pack('U*')
+    # => "\xF8\x90\x80\x80\x80"
+    s.unpack('U*')
+    # => [4194304]
+
+- <tt>'w'</tt> - BER-encoded integer
+  (see {BER enocding}[https://en.wikipedia.org/wiki/X.690#BER_encoding]):
+
+    s = [1073741823].pack('w*')
+    # => "\x83\xFF\xFF\xFF\x7F"
+    s.unpack('w*')
+    # => [1073741823]
+
+==== Modifiers for \Integer Directives
+
+For directives in
+<tt>'i'</tt>,
+<tt>'I'</tt>,
+<tt>'s'</tt>,
+<tt>'S'</tt>,
+<tt>'l'</tt>,
+<tt>'L'</tt>,
+<tt>'q'</tt>,
+<tt>'Q'</tt>,
+<tt>'j'</tt>, and
+<tt>'J'</tt>,
+these modifiers may be suffixed:
+
+- <tt>'!'</tt> or <tt>'_'</tt> - Underlying platform’s native size.
+- <tt>'>'</tt> - Big-endian.
+- <tt>'<'</tt> - Little-endian.
+
+=== \Float Directives
+
+Each float directive specifies the packing or unpacking
+for one element in the input or output array.
+
+==== Single-Precision \Float Directives
+
+- <tt>'F'</tt> or <tt>'f'</tt> - Native format:
+
+    s = [3.0].pack('F') # => "\x00\x00@@"
+    s.unpack('F')       # => [3.0]
+
+- <tt>'e'</tt> - Little-endian:
+
+    s = [3.0].pack('e') # => "\x00\x00@@"
+    s.unpack('e')       # => [3.0]
+
+- <tt>'g'</tt> - Big-endian:
+
+    s = [3.0].pack('g') # => "@@\x00\x00"
+    s.unpack('g')       # => [3.0]
+
+==== Double-Precision \Float Directives
+
+- <tt>'D'</tt> or <tt>'d'</tt> - Native format:
+
+    s = [3.0].pack('D') # => "\x00\x00\x00\x00\x00\x00\b@"
+    s.unpack('D')       # => [3.0]
+
+- <tt>'E'</tt> - Little-endian:
+
+    s = [3.0].pack('E') # => "\x00\x00\x00\x00\x00\x00\b@"
+    s.unpack('E')       # => [3.0]
+
+- <tt>'G'</tt> - Big-endian:
+
+    s = [3.0].pack('G') # => "@\b\x00\x00\x00\x00\x00\x00"
+    s.unpack('G')       # => [3.0]
+
+A float directive may be infinity or not-a-number:
+
+  inf = 1.0/0.0                  # => Infinity
+  [inf].pack('f')                # => "\x00\x00\x80\x7F"
+  "\x00\x00\x80\x7F".unpack('f') # => [Infinity]
+
+  nan = inf/inf                  # => NaN
+  [nan].pack('f')                # => "\x00\x00\xC0\x7F"
+  "\x00\x00\xC0\x7F".unpack('f') # => [NaN]
+
+=== \String Directives
+
+Each string directive specifies the packing or unpacking
+for one byte in the input or output string.
+
+==== Binary \String Directives
+
+- <tt>'A'</tt> - Arbitrary binary string (space padded; count is width);
+  +nil+ is treated as the empty string:
+
+    ['foo'].pack('A')    # => "f"
+    ['foo'].pack('A*')   # => "foo"
+    ['foo'].pack('A2')   # => "fo"
+    ['foo'].pack('A4')   # => "foo "
+    [nil].pack('A')      # => " "
+    [nil].pack('A*')     # => ""
+    [nil].pack('A2')     # => "  "
+    [nil].pack('A4')     # => "    "
+
+    "foo\0".unpack('A')      # => ["f"]
+    "foo\0".unpack('A4')     # => ["foo"]
+    "foo\0bar".unpack('A10') # => ["foo\x00bar"] # Reads past "\0".
+    "foo ".unpack('A')       # => ["f"]
+    "foo ".unpack('A4')      # => ["foo"]
+    "foo".unpack('A4')       # => ["foo"]
+
+    russian = "\u{442 435 441 442}" # => "те�т"
+    russian.size         # => 4
+    russian.bytesize     # => 8
+    [russian].pack('A')  # => "\xD1"
+    [russian].pack('A*') # => "\xD1\x82\xD0\xB5\xD1\x81\xD1\x82"
+    russian.unpack('A')  # => ["\xD1"]
+    russian.unpack('A2') # => ["\xD1\x82"]
+    russian.unpack('A4') # => ["\xD1\x82\xD0\xB5"]
+    russian.unpack('A*') # => ["\xD1\x82\xD0\xB5\xD1\x81\xD1\x82"]
+
+- <tt>'a'</tt> - Arbitrary binary string (null padded; count is width):
+
+    ["foo"].pack('a')    # => "f"
+    ["foo"].pack('a*')   # => "foo"
+    ["foo"].pack('a2')   # => "fo"
+    ["foo\0"].pack('a4') # => "foo\x00"
+    [nil].pack('a')      # => "\x00"
+    [nil].pack('a*')     # => ""
+    [nil].pack('a2')     # => "\x00\x00"
+    [nil].pack('a4')     # => "\x00\x00\x00\x00"
+
+    "foo\0".unpack('a')     # => ["f"]
+    "foo\0".unpack('a4')    # => ["foo\x00"]
+    "foo ".unpack('a4')     # => ["foo "]
+    "foo".unpack('a4')      # => ["foo"]
+    "foo\0bar".unpack('a4') # => ["foo\x00"] # Reads past "\0".
+
+- <tt>'Z'</tt> - Same as <tt>'a'</tt>,
+  except that null is added or ignored with <tt>'*'</tt>:
+
+    ["foo"].pack('Z*')   # => "foo\x00"
+    [nil].pack('Z*')     # => "\x00"
+
+    "foo\0".unpack('Z*')    # => ["foo"]
+    "foo".unpack('Z*')      # => ["foo"]
+    "foo\0bar".unpack('Z*') # => ["foo"] # Does not read past "\0".
+
+==== Bit \String Directives
+
+- <tt>'B'</tt> - Bit string (high byte first):
+
+    ['11111111' + '00000000'].pack('B*') # => "\xFF\x00"
+    ['10000000' + '01000000'].pack('B*') # => "\x80@"
+
+    ['1'].pack('B0') # => ""
+    ['1'].pack('B1') # => "\x80"
+    ['1'].pack('B2') # => "\x80\x00"
+    ['1'].pack('B3') # => "\x80\x00"
+    ['1'].pack('B4') # => "\x80\x00\x00"
+    ['1'].pack('B5') # => "\x80\x00\x00"
+    ['1'].pack('B6') # => "\x80\x00\x00\x00"
+
+    "\xff\x00".unpack("B*") # => ["1111111100000000"]
+    "\x01\x02".unpack("B*") # => ["0000000100000010"]
+
+    "".unpack("B0")     # => [""]
+    "\x80".unpack("B1") # => ["1"]
+    "\x80".unpack("B2") # => ["10"]
+    "\x80".unpack("B3") # => ["100"]
+
+- <tt>'b'</tt> - Bit string (low byte first):
+
+    ['11111111' + '00000000'].pack('b*') # => "\xFF\x00"
+    ['10000000' + '01000000'].pack('b*') # => "\x01\x02"
+
+    ['1'].pack('b0') # => ""
+    ['1'].pack('b1') # => "\x01"
+    ['1'].pack('b2') # => "\x01\x00"
+    ['1'].pack('b3') # => "\x01\x00"
+    ['1'].pack('b4') # => "\x01\x00\x00"
+    ['1'].pack('b5') # => "\x01\x00\x00"
+    ['1'].pack('b6') # => "\x01\x00\x00\x00"
+
+    "\xff\x00".unpack("b*") # => ["1111111100000000"]
+    "\x01\x02".unpack("b*") # => ["1000000001000000"]
+
+    "".unpack("b0")     # => [""]
+    "\x01".unpack("b1") # => ["1"]
+    "\x01".unpack("b2") # => ["10"]
+    "\x01".unpack("b3") # => ["100"]
+
+==== Hex \String Directives
+
+- <tt>'H'</tt> - Hex string (high nibble first):
+
+    ['10ef'].pack('H*')    # => "\x10\xEF"
+    ['10ef'].pack('H0')    # => ""
+    ['10ef'].pack('H3')    # => "\x10\xE0"
+    ['10ef'].pack('H5')    # => "\x10\xEF\x00"
+
+    ['fff'].pack('H3')    # => "\xFF\xF0"
+    ['fff'].pack('H4')    # => "\xFF\xF0"
+    ['fff'].pack('H5')    # => "\xFF\xF0\x00"
+    ['fff'].pack('H6')    # => "\xFF\xF0\x00"
+    ['fff'].pack('H7')    # => "\xFF\xF0\x00\x00"
+    ['fff'].pack('H8')    # => "\xFF\xF0\x00\x00"
+
+    "\x10\xef".unpack('H*')    # => ["10ef"]
+    "\x10\xef".unpack('H0')    # => [""]
+    "\x10\xef".unpack('H1')    # => ["1"]
+    "\x10\xef".unpack('H2')    # => ["10"]
+    "\x10\xef".unpack('H3')    # => ["10e"]
+    "\x10\xef".unpack('H4')    # => ["10ef"]
+    "\x10\xef".unpack('H5')    # => ["10ef"]
+
+- <tt>'h'</tt> - Hex string (low nibble first):
+
+    ['10ef'].pack('h*') # => "\x01\xFE"
+    ['10ef'].pack('h0') # => ""
+    ['10ef'].pack('h3') # => "\x01\x0E"
+    ['10ef'].pack('h5') # => "\x01\xFE\x00"
+
+    ['fff'].pack('h3') # => "\xFF\x0F"
+    ['fff'].pack('h4') # => "\xFF\x0F"
+    ['fff'].pack('h5') # => "\xFF\x0F\x00"
+    ['fff'].pack('h6') # => "\xFF\x0F\x00"
+    ['fff'].pack('h7') # => "\xFF\x0F\x00\x00"
+    ['fff'].pack('h8') # => "\xFF\x0F\x00\x00"
+
+    "\x01\xfe".unpack('h*') # => ["10ef"]
+    "\x01\xfe".unpack('h0') # => [""]
+    "\x01\xfe".unpack('h1') # => ["1"]
+    "\x01\xfe".unpack('h2') # => ["10"]
+    "\x01\xfe".unpack('h3') # => ["10e"]
+    "\x01\xfe".unpack('h4') # => ["10ef"]
+    "\x01\xfe".unpack('h5') # => ["10ef"]
+
+==== Pointer \String Directives
+
+- <tt>'P'</tt> - Pointer to a structure (fixed-length string):
+
+    s = ['abc'].pack('P')  # => "\xE0O\x7F\xE5\xA1\x01\x00\x00"
+    s.unpack('P*')         # => ["abc"]
+    ".".unpack("P")        # => []
+    ("\0" * 8).unpack("P") # => [nil]
+    [nil].pack("P")        # => "\x00\x00\x00\x00\x00\x00\x00\x00"
+
+- <tt>'p'</tt> - Pointer to a null-terminated string:
+
+    s = ['abc'].pack('p')  # => "(\xE4u\xE5\xA1\x01\x00\x00"
+    s.unpack('p*')         # => ["abc"]
+    ".".unpack("p")        # => []
+    ("\0" * 8).unpack("p") # => [nil]
+    [nil].pack("p")        # => "\x00\x00\x00\x00\x00\x00\x00\x00"
+
+==== Other \String Directives
+
+- <tt>'M'</tt> - Quoted printable, MIME encoding;
+  text mode, but input must use LF and output LF;
+  (see {RFC 2045}[https://www.ietf.org/rfc/rfc2045.txt]):
+
+    ["a b c\td \ne"].pack('M') # => "a b c\td =\n\ne=\n"
+    ["\0"].pack('M')           # => "=00=\n"
+
+    ["a"*1023].pack('M') == ("a"*73+"=\n")*14+"a=\n"     # => true
+    ("a"*73+"=\na=\n").unpack('M') == ["a"*74]           # => true
+    (("a"*73+"=\n")*14+"a=\n").unpack('M') == ["a"*1023] # => true
+
+    "a b c\td =\n\ne=\n".unpack('M')    # => ["a b c\td \ne"]
+    "=00=\n".unpack('M')    # => ["\x00"]
+
+    "pre=31=32=33after".unpack('M') # => ["pre123after"]
+    "pre=\nafter".unpack('M')       # => ["preafter"]
+    "pre=\r\nafter".unpack('M')     # => ["preafter"]
+    "pre=".unpack('M')              # => ["pre="]
+    "pre=\r".unpack('M')            # => ["pre=\r"]
+    "pre=hoge".unpack('M')          # => ["pre=hoge"]
+    "pre==31after".unpack('M')      # => ["pre==31after"]
+    "pre===31after".unpack('M')     # => ["pre===31after"]
+
+- <tt>'m'</tt> - Base64 encoded string;
+  count specifies input bytes between each newline,
+  rounded down to nearest multiple of 3;
+  if count is zero, no newlines are added;
+  (see {RFC 4648}[https://www.ietf.org/rfc/rfc4648.txt]):
+
+    [""].pack('m')             # => ""
+    ["\0"].pack('m')           # => "AA==\n"
+    ["\0\0"].pack('m')         # => "AAA=\n"
+    ["\0\0\0"].pack('m')       # => "AAAA\n"
+    ["\377"].pack('m')         # => "/w==\n"
+    ["\377\377"].pack('m')     # => "//8=\n"
+    ["\377\377\377"].pack('m') # => "////\n"
+
+    "".unpack('m')       # => [""]
+    "AA==\n".unpack('m') # => ["\x00"]
+    "AAA=\n".unpack('m') # => ["\x00\x00"]
+    "AAAA\n".unpack('m') # => ["\x00\x00\x00"]
+    "/w==\n".unpack('m') # => ["\xFF"]
+    "//8=\n".unpack('m') # => ["\xFF\xFF"]
+    "////\n".unpack('m') # => ["\xFF\xFF\xFF"]
+    "A\n".unpack('m')    # => [""]
+    "AA\n".unpack('m')   # => ["\x00"]
+    "AA=\n".unpack('m')  # => ["\x00"]
+    "AAA\n".unpack('m')  # => ["\x00\x00"]
+
+    [""].pack('m0')             # => ""
+    ["\0"].pack('m0')           # => "AA=="
+    ["\0\0"].pack('m0')         # => "AAA="
+    ["\0\0\0"].pack('m0')       # => "AAAA"
+    ["\377"].pack('m0')         # => "/w=="
+    ["\377\377"].pack('m0')     # => "//8="
+    ["\377\377\377"].pack('m0') # => "////"
+
+    "".unpack('m0')     # => [""]
+    "AA==".unpack('m0') # => ["\x00"]
+    "AAA=".unpack('m0') # => ["\x00\x00"]
+    "AAAA".unpack('m0') # => ["\x00\x00\x00"]
+    "/w==".unpack('m0') # => ["\xFF"]
+    "//8=".unpack('m0') # => ["\xFF\xFF"]
+    "////".unpack('m0') # => ["\xFF\xFF\xFF"]
+
+- <tt>'u'</tt> - UU-encoded string:
+
+    [0].pack("U")          # => "\u0000"
+    [0x3fffffff].pack("U") # => "\xFC\xBF\xBF\xBF\xBF\xBF"
+    [0x40000000].pack("U") # => "\xFD\x80\x80\x80\x80\x80"
+    [0x7fffffff].pack("U") # => "\xFD\xBF\xBF\xBF\xBF\xBF"
+
+=== Offset Directives
+
+- <tt>'@'</tt> - Begin packing at the given byte offset;
+  for packing, null fill if necessary:
+
+    [1, 2].pack("C@0C") # => "\x02"
+    [1, 2].pack("C@1C") # => "\x01\x02"
+    [1, 2].pack("C@5C") # => "\x01\x00\x00\x00\x00\x02"
+
+    "\x01\x00\x00\x02".unpack("C@3C") # => [1, 2]
+    "\x00".unpack("@1C")              # => [nil]
+
+- <tt>'X'</tt> - Back up a byte:
+
+    [0, 1, 2].pack("CCXC")    # => "\x00\x02"
+    [0, 1, 2].pack("CCX2C")   # => "\x02"
+    "\x00\x02".unpack("CCXC") # => [0, 2, 2]
+
+=== Null Byte Direcive
+
+- <tt>'x'</tt> - Null byte:
+
+    [].pack("x0")                # => ""
+    [].pack("x")                 # => "\x00"
+    [].pack("x8")                # => "\x00\x00\x00\x00\x00\x00\x00\x00"
+    "\x00\x00\x02".unpack("CxC") # => [0, 2]
diff --git a/doc/rdoc/markup_reference.rb b/doc/rdoc/markup_reference.rb
new file mode 100644
index 0000000000..66ec6786c0
--- /dev/null
+++ b/doc/rdoc/markup_reference.rb
@@ -0,0 +1,1257 @@
+require 'rdoc'
+
+# \Class \RDoc::MarkupReference exists only to provide a suitable home
+# for a reference document for \RDoc markup.
+#
+# All objects defined in this class -- classes, modules, methods, aliases,
+# attributes, and constants -- are solely for illustrating \RDoc markup,
+# and have no other legitimate use.
+#
+# = \RDoc Markup Reference
+#
+# Notes:
+#
+# - Examples in this reference are Ruby code and comments;
+#   certain differences from other sources
+#   (such as C code and comments) are noted.
+# - An example that shows rendered HTML output
+#   displays that output in a blockquote:
+#
+#   Rendered HTML:
+#   >>>
+#     Some stuff
+#
+# \RDoc-generated documentation is derived from and controlled by:
+#
+# - Single-line or multi-line comments that precede certain definitions;
+#   see {Markup in Comments}[rdoc-ref:RDoc::MarkupReference@Markup+in+Comments].
+# - \RDoc directives in trailing comments (on the same line as code);
+#   see <tt>:nodoc:</tt>, <tt>:doc:</tt>, and <tt>:notnew</tt>.
+# - \RDoc directives in single-line comments;
+#   see other {Directives}[rdoc-ref:RDoc::MarkupReference@Directives].
+# - The Ruby code itself (but not from C code);
+#   see {Documentation Derived from Ruby Code}[rdoc-ref:RDoc::MarkupReference@Documentation+Derived+from+Ruby+Code].
+#
+# == Markup in Comments
+#
+# The treatment of markup in comments varies according to the type of file:
+#
+# - <tt>.rb</tt> (Ruby code file): markup is parsed from Ruby comments.
+# - <tt>.c</tt> (C code file): markup is parsed from C comments.
+# - <tt>.rdoc</tt> (RDoc text file): markup is parsed from the entire file.
+#
+# The comment associated with
+# a Ruby class, module, method, alias, constant, or attribute
+# becomes the documentation for that defined object:
+#
+# - In a Ruby file, that comment immediately precedes
+#   the definition of the object.
+# - In a C file, that comment immediately precedes
+#   the function that implements a method,
+#   or otherwise immediately precedes the definition of the object.
+#
+# In either a Ruby or a C file,
+# \RDoc ignores comments that do not precede object definitions.
+#
+# In an \RDoc file, the text is not associated with any code object,
+# but may (depending on how the documentation is built),
+# become a separate page.
+#
+# Almost all examples on this page are all RDoc-like;
+# that is, they have no comment markers like Ruby <tt>#</tt>
+# or C <tt>/* ... */</tt>.
+#
+# === Margins
+#
+# In a multi-line comment,
+# \RDoc looks for the comment's natural left margin,
+# which becomes the <em>base margin</em> for the comment
+# and is the initial <em>current margin</em> for for the comment.
+#
+# The current margin can change, and does so, for example in a list.
+#
+# === Blocks
+#
+# It's convenient to think of \RDoc markup input as a sequence of _blocks_
+# of various types (details at the links):
+#
+# - {Paragraph}[rdoc-ref:RDoc::MarkupReference@Paragraphs]:
+#   an ordinary paragraph.
+# - {Verbatim text block}[rdoc-ref:RDoc::MarkupReference@Verbatim+Text+Blocks]:
+#   a block of text to be rendered literally.
+# - {Code block}[rdoc-ref:RDoc::MarkupReference@Code+Blocks]:
+#   a verbatim text block containing Ruby code,
+#   to be rendered with code highlighting.
+# - {Block quote}[rdoc-ref:RDoc::MarkupReference@Block+Quotes]:
+#   a longish quoted passage, to be rendered with indentation
+#   instead of quote marks.
+# - {List}[rdoc-ref:RDoc::MarkupReference@Lists]: items for
+#   a bullet list, numbered list, lettered list, or labeled list.
+# - {Heading}[rdoc-ref:RDoc::MarkupReference@Headings]:
+#   a section heading.
+# - {Horizontal rule}[rdoc-ref:RDoc::MarkupReference@Horizontal+Rules]:
+#   a line across the rendered page.
+# - {Directive}[rdoc-ref:RDoc::MarkupReference@Directives]:
+#   various special directions for the rendering.
+# - {Text Markup}[rdoc-ref:RDoc:MarkupReference@Text+Markup]:
+#   text to be rendered in a special way.
+#
+# About the blocks:
+#
+# - Except for a paragraph, a block is distinguished by its indentation,
+#   or by unusual initial or embedded characters.
+# - Any block may appear independently
+#   (that is, not nested in another block);
+#   some blocks may be nested, as detailed below.
+#
+# ==== Paragraphs
+#
+# A paragraph consists of one or more non-empty lines of ordinary text,
+# each beginning at the current margin.
+#
+# Note: Here, <em>ordinary text</em> means text that is <em>not identified</em>
+# by indentation, or by unusual initial or embedded characters.
+# See below.
+#
+# Paragraphs are separated by one or more empty lines.
+#
+# Example input:
+#
+#   \RDoc produces HTML and command-line documentation for Ruby projects.
+#   \RDoc includes the rdoc and ri tools for generating and displaying
+#   documentation from the command-line.
+#
+#   You'll love it.
+#
+# Rendered HTML:
+# >>>
+#   \RDoc produces HTML and command-line documentation for Ruby projects.
+#   \RDoc includes the rdoc and ri tools for generating and displaying
+#   documentation from the command-line.
+#
+#   You'll love it.
+#
+# A paragraph may contain nested blocks, including:
+#
+# - {Verbatim text blocks}[rdoc-ref:RDoc::MarkupReference@Verbatim+Text+Blocks].
+# - {Code blocks}[rdoc-ref:RDoc::MarkupReference@Code+Blocks].
+# - {Block quotes}[rdoc-ref:RDoc::MarkupReference@Block+Quotes].
+# - {Lists}[rdoc-ref:RDoc::MarkupReference@Lists].
+# - {Headings}[rdoc-ref:RDoc::MarkupReference@Headings].
+# - {Horizontal rules}[rdoc-ref:RDoc::MarkupReference@Horizontal+Rules].
+# - {Text Markup}[rdoc-ref:RDoc:MarkupReference@Text+Markup].
+#
+# ==== Verbatim Text Blocks
+#
+# Text indented farther than the current margin becomes a <em>verbatim text block</em>
+# (or a code block, described next).
+# In the rendered HTML, such text:
+#
+# - Is indented.
+# - Has a contrasting background color.
+#
+# The verbatim text block ends at the first line beginning at the current margin.
+#
+# Example input:
+#
+#   This is not verbatim text.
+#
+#     This is verbatim text.
+#       Whitespace is honored.     # See?
+#         Whitespace is honored.     # See?
+#
+#     This is still the same verbatim text block.
+#
+#   This is not verbatim text.
+#
+# Rendered HTML:
+# >>>
+#   This is not verbatim text.
+#
+#     This is verbatim text.
+#       Whitespace is honored.     # See?
+#         Whitespace is honored.     # See?
+#
+#     This is still the same verbatim text block.
+#
+#   This is not verbatim text.
+#
+# A verbatim text block may not contain nested blocks of any kind
+# -- it's verbatim.
+#
+# ==== Code Blocks
+#
+# A special case of verbatim text is the <em>code block</em>,
+# which is merely verbatim text that \RDoc recognizes as Ruby code:
+#
+# In the rendered HTML, the code block:
+#
+# - Is indented.
+# - Has a contrasting background color.
+# - Has syntax highlighting.
+#
+# Example input:
+#
+#   Consider this method:
+#
+#     def foo(name = '', value = 0)
+#       @name = name      # Whitespace is still honored.
+#       @value = value
+#     end
+#
+#
+# Rendered HTML:
+# >>>
+#   Consider this method:
+#
+#     def foo(name = '', value = 0)
+#       @name = name      # Whitespace is still honored.
+#       @value = value
+#     end
+#
+# Pro tip:  If your indented Ruby code does not get highlighted,
+# it may contain a syntax error.
+#
+# A code block may not contain nested blocks of any kind
+# -- it's verbatim.
+#
+# ==== Block Quotes
+#
+# You can use the characters <tt>>>></tt> (unindented),
+# followed by indented text, to treat the text
+# as a {block quote}[https://en.wikipedia.org/wiki/Block_quotation]:
+#
+# Example input:
+#
+#   Here's a block quote:
+#   >>>
+#     Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer
+#     commodo quam iaculis massa posuere, dictum fringilla justo pulvinar.
+#     Quisque turpis erat, pharetra eu dui at, sollicitudin accumsan nulla.
+#
+#     Aenean congue ligula eu ligula molestie, eu pellentesque purus
+#     faucibus. In id leo non ligula condimentum lobortis. Duis vestibulum,
+#     diam in pellentesque aliquet, mi tellus placerat sapien, id euismod
+#     purus magna ut tortor.
+#
+# Rendered HTML:
+#
+# >>>
+#   Here's a block quote:
+#   >>>
+#     Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer
+#     commodo quam iaculis massa posuere, dictum fringilla justo pulvinar.
+#     Quisque turpis erat, pharetra eu dui at, sollicitudin accumsan nulla.
+#
+#     Aenean congue ligula eu ligula molestie, eu pellentesque purus
+#     faucibus. In id leo non ligula condimentum lobortis. Duis vestibulum,
+#     diam in pellentesque aliquet, mi tellus placerat sapien, id euismod
+#     purus magna ut tortor.
+#
+# Note that, unlike verbatim text, single newlines are not honored,
+# but that a double newline begins a new paragraph in the block quote.
+#
+# A block quote may contain nested blocks, including:
+#
+# - Other block quotes.
+# - {Paragraphs}[rdoc-ref:RDoc::MarkupReference@Paragraphs].
+# - {Verbatim text blocks}[rdoc-ref:RDoc::MarkupReference@Verbatim+Text+Blocks].
+# - {Code blocks}[rdoc-ref:RDoc::MarkupReference@Code+Blocks].
+# - {Lists}[rdoc-ref:RDoc::MarkupReference@Lists].
+# - {Headings}[rdoc-ref:RDoc::MarkupReference@Headings].
+# - {Horizontal rules}[rdoc-ref:RDoc::MarkupReference@Horizontal+Rules].
+# - {Text Markup}[rdoc-ref:RDoc:MarkupReference@Text+Markup].
+#
+# ==== Lists
+#
+# Each type of list item is marked by a special beginning:
+#
+# - Bullet list item: Begins with a hyphen or asterisk.
+# - Numbered list item: Begins with digits and a period.
+# - Lettered list item: Begins with an alphabetic character and a period.
+# - Labeled list item: Begins with one of:
+#   - Square-bracketed text.
+#   - A word followed by two colons.
+#
+# A list begins with a list item and continues, even across blank lines,
+# as long as list items of the same type are found at the same indentation level.
+#
+# A new list resets the current margin inward.
+# Additional lines of text aligned at that margin
+# are part of the continuing list item.
+#
+# A list item may be continued on additional lines that are aligned
+# with the first line.  See examples below.
+#
+# A list item may contain nested blocks, including:
+#
+# - Other lists of any type.
+# - {Paragraphs}[rdoc-ref:RDoc::MarkupReference@Paragraphs].
+# - {Verbatim text blocks}[rdoc-ref:RDoc::MarkupReference@Verbatim+Text+Blocks].
+# - {Code blocks}[rdoc-ref:RDoc::MarkupReference@Code+Blocks].
+# - {Block quotes}[rdoc-ref:RDoc::MarkupReference@Block+Quotes].
+# - {Headings}[rdoc-ref:RDoc::MarkupReference@Headings].
+# - {Horizontal rules}[rdoc-ref:RDoc::MarkupReference@Horizontal+Rules].
+# - {Text Markup}[rdoc-ref:RDoc:MarkupReference@Text+Markup].
+#
+# ===== Bullet Lists
+#
+# A bullet list item begins with a hyphen or asterisk.
+#
+# Example input:
+#
+#   - An item.
+#   - Another.
+#   - An item spanning
+#     multiple lines.
+#
+#   * Yet another.
+#   - Last one.
+#
+# Rendered HTML:
+# >>>
+#   - An item.
+#   - Another.
+#   - An item spanning
+#     multiple lines.
+#
+#   * Yet another.
+#   - Last one.
+#
+# ===== Numbered Lists
+#
+# A numbered list item begins with digits and a period.
+#
+# The items are automatically re-numbered.
+#
+# Example input:
+#
+#   100. An item.
+#   10. Another.
+#   1. An item spanning
+#      multiple lines.
+#
+#   1. Yet another.
+#   1000. Last one.
+#
+# Rendered HTML:
+# >>>
+#   100. An item.
+#   10. Another.
+#   1. An item spanning
+#      multiple lines.
+#
+#   1. Yet another.
+#   1000. Last one.
+#
+# ===== Lettered Lists
+#
+# A numbered list item begins with a letters and a period.
+#
+# The items are automatically "re-lettered."
+#
+# Example input:
+#
+#   z. An item.
+#   y. Another.
+#   x. An item spanning
+#      multiple lines.
+#
+#   x. Yet another.
+#   a. Last one.
+#
+# Rendered HTML:
+# >>>
+#   z. An item.
+#   y. Another.
+#
+#   x. Yet another.
+#   a. Last one.
+#
+# ===== Labeled Lists
+#
+# A labeled list item begins with one of:
+#
+# - Square-bracketed text: the label and text are on two lines.
+# - A word followed by two colons: the label and text are on the same line.
+#
+# Example input:
+#
+#   [foo] An item.
+#   bat:: Another.
+#   [bag] An item spanning
+#         multiple lines.
+#
+#   [bar baz] Yet another.
+#   bam:: Last one.
+#
+# Rendered HTML:
+# >>>
+#   [foo] An item.
+#   bat:: Another.
+#   [bag] An item spanning
+#         multiple lines.
+#
+#   [bar baz] Yet another.
+#   bam:: Last one.
+#
+# ==== Headings
+#
+# A heading begins with up to six equal-signs, followed by heading text.
+# Whitespace between those and the heading text is optional.
+#
+# Examples:
+#
+#   = Section 1
+#   == Section 1.1
+#   === Section 1.1.1
+#   === Section 1.1.2
+#   == Section 1.2
+#   = Section 2
+#   = Foo
+#   == Bar
+#   === Baz
+#   ==== Bam
+#   ===== Bat
+#   ====== Bad
+#   ============Still a Heading (Level 6)
+#   \== Not a Heading
+#
+# A heading may contain only one type of nested block:
+#
+# - {Text Markup}[rdoc-ref:RDoc:MarkupReference@Text+Markup].
+#
+# ==== Horizontal Rules
+#
+# A horizontal rule consists of a line with three or more hyphens
+# and nothing more.
+#
+# Example input:
+#
+#   ---
+#   --- Not a horizontal rule.
+#
+#   -- Also not a horizontal rule.
+#   ---
+#
+# Rendered HTML:
+# >>>
+#   ---
+#   --- Not a horizontal rule.
+#
+#   -- Also not a horizontal rule.
+#   ---
+#
+# ==== Directives
+#
+# ===== Directives for Allowing or Suppressing Documentation
+#
+# - <tt># :stopdoc:</tt>:
+#
+#   - Appears on a line by itself.
+#   - Specifies that \RDoc should ignore markup
+#     until next <tt>:startdoc:</tt> directive or end-of-file.
+#
+# - <tt># :startdoc:</tt>:
+#
+#   - Appears on a line by itself.
+#   - Specifies that \RDoc should resume parsing markup.
+#
+# - <tt># :enddoc:</tt>:
+#
+#   - Appears on a line by itself.
+#   - Specifies that \RDoc should ignore markup to end-of-file
+#     regardless of other directives.
+#
+# - <tt># :nodoc:</tt>:
+#
+#   - Appended to a line of code
+#     that defines a class, module, method, alias, constant, or attribute.
+#   - Specifies that the defined object should not be documented.
+#
+# - <tt># :nodoc: all</tt>:
+#
+#   - Appended to a line of code
+#     that defines a class or module.
+#   - Specifies that the class or module should not be documented.
+#     By default, however, a nested class or module _will_ be documented.
+#
+# - <tt># :doc:</tt>:
+#
+#   - Appended to a line of code
+#     that defines a class, module, method, alias, constant, or attribute.
+#   - Specifies the defined object should be documented, even if otherwise
+#     would not be documented.
+#
+# - <tt># :notnew:</tt> (aliased as <tt>:not_new:</tt> and <tt>:not-new:</tt>):
+#
+#   - Appended to a line of code
+#     that defines instance method +initialize+.
+#   - Specifies that singleton method +new+ should not be documented.
+#     By default, Ruby fakes a corresponding singleton method +new+,
+#     which \RDoc includes in the documentation.
+#     Note that instance method +initialize+ is private, and so by default
+#     is not documented.
+#
+# For Ruby code, but not for other \RDoc sources,
+# there is a shorthand for <tt>:stopdoc:</tt> and <tt>:startdoc:</tt>:
+#
+#   # Documented.
+#   #--
+#   # Not documented.
+#   #++
+#   # Documented.
+#
+# For C code, any of directives <tt>:startdoc:</tt>, <tt>:enddoc:</tt>,
+# and <tt>:nodoc:</tt> may appear in a stand-alone comment:
+#
+#   /* :startdoc: */
+#   /* :stopdoc: */
+#   /* :enddoc: */
+#
+# ===== Directive for Specifying \RDoc Source Format
+#
+# - <tt># :markup: _type_</tt>:
+#
+#   - Appears on a line by itself.
+#   - Specifies the format for the \RDoc input;
+#     parameter +type+ is one of +markdown+, +rd+, +rdoc+, +tomdoc+.
+#
+# ===== Directives for HTML Output
+#
+# - <tt># :title: _text_</tt>:
+#
+#   - Appears on a line by itself.
+#   - Specifies the title for the HTML output.
+#
+# - <tt># :main: _filename_</tt>:
+#   - Appears on a line by itself.
+#   - Specifies the HTML file to be displayed first.
+#
+# ===== Directives for Method Documentation
+#
+# - <tt># :call-seq:</tt>:
+#
+#   - Appears on a line by itself.
+#   - Specifies the calling sequence to be reported in the HTML,
+#     overriding the actual calling sequence in the code.
+#     See method #call_seq_directive.
+#
+#   Note that \RDoc can build the calling sequence for a Ruby-coded method,
+#   but not for other languages.
+#   You may want to override that by explicitly giving a <tt>:call-seq:</tt>
+#   directive if you want to include:
+#
+#   - A return type, which is not automatically inferred.
+#   - Multiple calling sequences.
+#
+#   For C code, the directive may appear in a stand-alone comment.
+#
+# - <tt># :args: _arg_names_</tt> (aliased as <tt>:arg:</tt>):
+#
+#   - Appears on a line by itself.
+#   - Specifies the arguments to be reported in the HTML,
+#     overriding the actual arguments in the code.
+#     See method #args_directive.
+#
+# - <tt># :yields: _arg_names_</tt> (aliased as <tt>:yield:</tt>):
+#
+#   - Appears on a line by itself.
+#   - Specifies the yield arguments to be reported in the HTML,
+#     overriding the actual yield in the code.
+#     See method #yields_directive.
+#
+# ===== Directives for Organizing Documentation
+#
+# By default, \RDoc groups:
+#
+# - Singleton methods together in alphabetical order.
+# - Instance methods and their aliases together in alphabetical order.
+# - Attributes and their aliases together in alphabetical order.
+#
+# You can use directives to modify those behaviors.
+#
+# - <tt># :section: _section_title_</tt>:
+#
+#   - Appears on a line by itself.
+#   - Specifies that following methods are to be grouped into the section
+#     with the given <em>section_title</em>,
+#     or into the default section if no title is given.
+#     The directive remains in effect until another such directive is given,
+#     but may be temporarily overridden by directive <tt>:category:</tt>.
+#     See below.
+#
+#   The comment block containing this directive:
+#
+#   - Must be separated by a blank line from the documentation for the next item.
+#   - May have one or more lines preceding the directive.
+#     These will be removed, along with any trailing lines that match them.
+#     Such lines may be visually helpful.
+#   - Lines of text that are not so removed become the descriptive text
+#     for the section.
+#
+#   Example:
+#
+#     # ----------------------------------------
+#     # :section: My Section
+#     # This is the section that I wrote.
+#     # See it glisten in the noon-day sun.
+#     # ----------------------------------------
+#
+#     ##
+#     # Comment for some_method
+#     def some_method
+#       # ...
+#     end
+#
+#   You can use directive <tt>:category:</tt> to temporarily
+#   override the current section.
+#
+# - <tt># :category: _section_title_</tt>:
+#
+#   - Appears on a line by itself.
+#   - Specifies that just one following method is to be included
+#     in the given section, or in the default section if no title is given.
+#     Subsequent methods are to be grouped into the current section.
+#
+# ===== Directive for Including a File
+#
+# - <tt># :include: _filepath_</tt>:
+#
+#   - Appears on a line by itself.
+#   - Specifies that the contents of the given file
+#     are to be included at this point.
+#     The file content is shifted to have the same indentation as the colon
+#     at the start of the directive.
+#
+#     The file is searched for in the directories
+#     given with the <tt>--include</tt> command-line option,
+#     or by default in the current directory.
+#
+#   For C code, the directive may appear in a stand-alone comment
+#
+# ==== Text Markup
+#
+# Text markup is metatext that affects HTML rendering:
+#
+# - Typeface: italic, bold, monofont.
+# - Character conversions: copyright, trademark, certain punctuation.
+# - Links.
+# - Escapes: marking text as "not markup."
+#
+# ===== Typeface Markup
+#
+# Typeface markup can specify that text is to be rendered
+# as italic, bold, or monofont.
+#
+# Typeface markup may contain only one type of nested block:
+#
+# - More typeface markup:
+#   italic, bold, monofont.
+#
+# ====== Italic
+#
+# Text may be marked as italic via HTML tag <tt><i></tt> or <tt><em></tt>.
+#
+# Example input:
+#
+#   <i>Italicized words</i> in a paragraph.
+#
+#   >>>
+#     <i>Italicized words in a block quote</i>.
+#
+#   - <i>Italicized words</i> in a list item.
+#
+#   ====== <i>Italicized words</i> in a Heading
+#
+#   <i>Italicized passage containing *bold* and +monofont+.</i>
+#
+# Rendered HTML:
+# >>>
+#   <i>Italicized words</i> in a paragraph.
+#
+#   >>>
+#     <i>Italicized words in a block quote</i>.
+#
+#   - <i>Italicized words</i> in a list item.
+#
+#   ====== <i>Italicized words</i> in a Heading
+#
+#   <i>Italicized passage containing *bold* and +monofont+.</i>
+#
+# A single word may be italicized via a shorthand:
+# prefixed and suffixed underscores.
+#
+# Example input:
+#
+#   _Italic_ in a paragraph.
+#
+#   >>>
+#     _Italic_ in a block quote.
+#
+#   - _Italic_ in a list item.
+#
+#   ====== _Italic_ in a Heading
+#
+# Rendered HTML:
+# >>>
+#   _Italic_ in a paragraph.
+#
+#   >>>
+#     _Italic_ in a block quote.
+#
+#   - _Italic_ in a list item.
+#
+#   ====== _Italic_ in a Heading
+#
+# ====== Bold
+#
+# Text may be marked as bold via HTML tag <tt><b></tt>.
+#
+# Example input:
+#
+#   <b>Bold words</b> in a paragraph.
+#
+#   >>>
+#     <b>Bold words</b> in a block quote.
+#
+#   - <b>Bold words</b> in a list item.
+#
+#   ====== <b>Bold words</b> in a Heading
+#
+#   <b>Bold passage containing _italics_ and +monofont+.</b>
+#
+# Rendered HTML:
+#
+# >>>
+#   <b>Bold words</b> in a paragraph.
+#
+#   >>>
+#     <b>Bold words</b> in a block quote.
+#
+#   - <b>Bold words</b> in a list item.
+#
+#   ====== <b>Bold words</b> in a Heading
+#
+#   <b>Bold passage containing _italics_ and +monofont+.</b>
+#
+# A single word may be made bold via a shorthand:
+# prefixed and suffixed asterisks.
+#
+# Example input:
+#
+#   *Bold* in a paragraph.
+#
+#   >>>
+#     *Bold* in a block quote.
+#
+#   - *Bold* in a list item.
+#
+#   ===== *Bold* in a Heading
+#
+# Rendered HTML:
+#
+# >>>
+#   *Bold* in a paragraph.
+#
+#   >>>
+#     *Bold* in a block quote.
+#
+#   - *Bold* in a list item.
+#
+#   ===== *Bold* in a Heading
+#
+# ====== Monofont
+#
+# Text may be marked as monofont
+# -- sometimes called 'typewriter font' --
+# via HTML tag <tt><tt></tt> or <tt><code></tt>.
+#
+# Example input:
+#
+#   <tt>Monofont words</tt> in a paragraph.
+#
+#   >>>
+#     <tt>Monofont words</tt> in a block quote.
+#
+#   - <tt>Monofont words</tt> in a list item.
+#
+#   ====== <tt>Monofont words</tt> in heading
+#
+#   <tt>Monofont passage containing _italics_ and *bold*.</tt>
+#
+# Rendered HTML:
+#
+# >>>
+#   <tt>Monofont words</tt> in a paragraph.
+#
+#   >>>
+#     <tt>Monofont words</tt> in a block quote.
+#
+#   - <tt>Monofont words</tt> in a list item.
+#
+#   ====== <tt>Monofont words</tt> in heading
+#
+#   <tt>Monofont passage containing _italics_ and *bold*.</tt>
+#
+# A single word may be made monofont by a shorthand:
+# prefixed and suffixed plus-signs.
+#
+# Example input:
+#
+#   +Monofont+ in a paragraph.
+#
+#   >>>
+#     +Monofont+ in a block quote.
+#
+#   - +Monofont+ in a list item.
+#
+#   ====== +Monofont+ in a Heading
+#
+# Rendered HTML:
+#
+# >>>
+#   +Monofont+ in a paragraph.
+#
+#   >>>
+#     +Monofont+ in a block quote.
+#
+#   - +Monofont+ in a list item.
+#
+#   ====== +Monofont+ in a Heading
+#
+# ==== Character Conversions
+#
+# Certain combinations of characters may be converted to special characters;
+# whether the conversion occurs depends on whether the special character
+# is available in the current encoding.
+#
+# - <tt>(c)</tt> converts to (c) (copyright character); must be lowercase.
+#
+# - <tt>(r)</tt> converts to (r) (registered trademark character); must be lowercase.
+#
+# - <tt>'foo'</tt> converts to 'foo' (smart single-quotes).
+#
+# - <tt>"foo"</tt> converts to "foo" (smart double-quotes).
+#
+# - <tt>foo ... bar</tt> converts to foo ... bar (1-character ellipsis).
+#
+# - <tt>foo -- bar</tt> converts to foo -- bar (1-character en-dash).
+#
+# - <tt>foo --- bar</tt> converts to foo --- bar (1-character em-dash).
+#
+# ==== Links
+#
+# Certain strings in \RDoc text are converted to links.
+# Any such link may be suppressed by prefixing a backslash.
+# This section shows how to link to various
+# targets.
+#
+# [Class]
+#
+#   - On-page: <tt>DummyClass</tt> links to DummyClass.
+#   - Off-page: <tt>RDoc::Alias</tt> links to RDoc::Alias.
+#
+# [Module]
+#
+#   - On-page: <tt>DummyModule</tt> links to DummyModule.
+#   - Off-page: <tt>RDoc</tt> links to RDoc.
+#
+# [Constant]
+#
+#   - On-page: <tt>DUMMY_CONSTANT</tt> links to DUMMY_CONSTANT.
+#   - Off-page: <tt>RDoc::Text::MARKUP_FORMAT</tt> links to RDoc::Text::MARKUP_FORMAT.
+#
+# [Singleton Method]
+#
+#   - On-page: <tt>::dummy_singleton_method</tt> links to ::dummy_singleton_method.
+#   - Off-page<tt>RDoc::TokenStream::to_html</tt> links to RDoc::TokenStream::to_html.
+#
+#   Note: Occasionally \RDoc is not linked to a method whose name
+#   has only special characters. Check whether the links you were expecting
+#   are actually there.  If not, you'll need to put in an explicit link;
+#   see below.
+#
+#   Pro tip: The link to any method is available in the alphabetical table of contents
+#   at the top left of the page for the class or module.
+#
+# [Instance Method]
+#
+#   - On-page: <tt>#dummy_instance_method</tt> links to #dummy_instance_method.
+#   - Off-page: <tt>RDoc::Alias#html_name</tt> links to RDoc::Alias#html_name.
+#
+#     See the Note and Pro Tip immediately above.
+#
+# [Attribute]
+#
+#   - On-page: <tt>#dummy_attribute</tt> links to #dummy_attribute.
+#   - Off-page: <tt>RDoc::Alias#name</tt> links to RDoc::Alias#name.
+#
+# [Alias]
+#
+#   - On-page: <tt>#dummy_instance_alias</tt> links to #dummy_instance_alias.
+#   - Off-page: <tt>RDoc::Alias#new_name</tt> links to RDoc::Alias#new_name.
+#
+# [Protocol +http+]
+#
+#   - Linked: <tt>http://yahoo.com</tt> links to http://yahoo.com.
+#
+# [Protocol +https+]
+#
+#   - Linked: <tt>https://github.com</tt> links to https://github.com.
+#
+# [Protocol +www+]
+#
+#   - Linked: <tt>www.yahoo.com</tt> links to www.yahoo.com.
+#
+# [Protocol +ftp+]
+#
+#   - Linked: <tt>ftp://nosuch.site</tt> links to ftp://nosuch.site.
+#
+# [Protocol +mailto+]
+#
+#   - Linked:  <tt>mailto:/foo@bar.com</tt> links to mailto://foo@bar.com.
+#
+# [Protocol +irc+]
+#
+#   - link: <tt>irc://irc.freenode.net/ruby</tt> links to irc://irc.freenode.net/ruby.
+#
+# [Image Filename Extensions]
+#
+#   - Link: <tt>https://www.ruby-lang.org/images/header-ruby-logo@2x.png</tt> is
+#     converted to an in-line HTML +img+ tag, which displays the image in the HTML:
+#
+#     https://www.ruby-lang.org/images/header-ruby-logo@2x.png
+#
+#     Also works for +bmp+, +gif+, +jpeg+, and +jpg+ files.
+#
+#     Note: Works only for a fully qualified URL.
+#
+# [Heading]
+#
+#   - Link: <tt>RDoc::RD@LICENSE</tt> links to RDoc::RDoc::RD@LICENSE.
+#
+#   Note that spaces in the actual heading are represented by <tt>+</tt> characters
+#   in the linkable text.
+#
+#   - Link: <tt>RDoc::Options@Saved+Options</tt>
+#     links to RDoc::Options@Saved+Options.
+#
+#   Punctuation and other special characters must be escaped like CGI.escape.
+#
+#   Pro tip: The link to any heading is available in the alphabetical table of contents
+#   at the top left of the page for the class or module.
+#
+# [Section]
+#
+#   See {Directives for Organizing Documentation}[#class-RDoc::MarkupReference-label-Directives+for+Organizing+Documentation].
+#
+#   - Link: <tt>RDoc::Markup::ToHtml@Visitor</tt> links to RDoc::Markup::ToHtml@Visitor.
+#
+#   If a section and a heading share the same name, the link target is the section.
+#
+# [Single-Word Text Link]
+#
+#   Use square brackets to create single-word text link:
+#
+#   - <tt>GitHub[https://github.com]</tt> links to GitHub[https://github.com].
+#
+# [Multi-Word Text Link]
+#
+#   Use square brackets and curly braces to create a multi-word text link.
+#
+#   - <tt>{GitHub home page}[https://github.com]</tt> links to
+#     {GitHub home page}[https://github.com].
+#
+# [<tt>rdoc-ref</tt> Scheme]
+#
+#   A link with the <tt>rdoc-ref:</tt> scheme links to the referenced item,
+#   if that item exists.
+#   The referenced item may be a class, module, method, file, etc.
+#
+#   - Class: <tt>Alias[rdoc-ref:RDoc::Alias]</tt> links to Alias[rdoc-ref:RDoc::Alias].
+#   - Module: <tt>RDoc[rdoc-ref:RDoc]</tt> links to RDoc[rdoc-ref:RDoc].
+#   - Method: <tt>foo[rdoc-ref:RDoc::Markup::ToHtml#handle_regexp_RDOCLINK]</tt>
+#     links to foo[rdoc-ref:RDoc::Markup::ToHtml#handle_regexp_RDOCLINK].
+#   - Constant: <tt>bar[rdoc-ref:RDoc::Markup::ToHtml::LIST_TYPE_TO_HTML]</tt>
+#     links to bar[rdoc-ref:RDoc::Markup::ToHtml::LIST_TYPE_TO_HTML].
+#   - Attribute: <tt>baz[rdoc-ref:RDoc::Markup::ToHtml#code_object]</tt>
+#     links to baz[rdoc-ref:RDoc::Markup::ToHtml#code_object].
+#   - Alias: <tt>bad[rdoc-ref:RDoc::MarkupReference#dummy_instance_alias]</tt> links to
+#     bad[rdoc-ref:RDoc::MarkupReference#dummy_instance_alias].
+#
+#   If the referenced item does not exist, no link is generated
+#   and entire <tt>rdoc-ref:</tt> square-bracketed clause is removed
+#   from the resulting text.
+#
+#   - <tt>Nosuch[rdoc-ref:RDoc::Nosuch]</tt> is rendered as
+#     Nosuch[rdoc-ref:RDoc::Nosuch].
+#
+#
+# [<tt>rdoc-label</tt> Scheme]
+#
+#   [Simple]
+#
+#     You can specify a link target using this form,
+#     where the second part cites the id of an HTML element.
+#
+#     This link refers to the constant +DUMMY_CONSTANT+ on this page:
+#
+#     - <tt>{DUMMY_CONSTANT}[rdoc-label:DUMMY_CONSTANT]</tt>
+#
+#     Thus:
+#
+#     {DUMMY_CONSTANT}[rdoc-label:DUMMY_CONSTANT]
+#
+#   [With Return]
+#
+#     You can specify both a link target and a local label
+#     that can be used as the target for a return link.
+#     These two links refer to each other:
+#
+#     - <tt>{go to addressee}[rdoc-label:addressee:sender]</tt>
+#     - <tt>{return to sender}[rdoc-label:sender:addressee]</tt>
+#
+#     Thus:
+#
+#     {go to addressee}[rdoc-label:addressee:sender]
+#
+#     Some text.
+#
+#     {return to sender}[rdoc-label:sender:addressee]
+#
+# [<tt>link:</tt> Scheme]
+#
+#   - <tt>link:README_rdoc.html</tt> links to link:README_rdoc.html.
+#
+# [<tt>rdoc-image</tt> Scheme]
+#
+#   Use the <tt>rdoc-image</tt> scheme to display an image that is also a link:
+#
+#     # {rdoc-image:path/to/image}[link_target]
+#
+#   - Link: <tt>{rdoc-image:https://www.ruby-lang.org/images/header-ruby-logo@2x.png}[https://www.ruby-lang.org]</tt>
+#     displays image <tt>https://www.ruby-lang.org/images/header-ruby-logo@2x.png</tt>
+#     as a link to <tt>https://www.ruby-lang.org</tt>.
+#
+#     {rdoc-image:https://www.ruby-lang.org/images/header-ruby-logo@2x.png}[https://www.ruby-lang.org]
+#
+#   A relative path as the target also works:
+#
+#   - Link: <tt>{rdoc-image:https://www.ruby-lang.org/images/header-ruby-logo@2x.png}[./Alias.html]</tt> links to <tt>./Alias.html</tt>
+#
+#     {rdoc-image:https://www.ruby-lang.org/images/header-ruby-logo@2x.png}[./Alias.html]
+#
+# === Escaping Text
+#
+# Text that would otherwise be interpreted as markup
+# can be "escaped," so that it is not interpreted as markup;
+# the escape character is the backslash (<tt>'\\'</tt>).
+#
+# In a verbatim text block or a code block,
+# the escape character is always preserved:
+#
+# Example input:
+#
+#   This is not verbatim text.
+#
+#     This is verbatim text, with an escape character \.
+#
+#   This is not a code block.
+#
+#     def foo
+#       'String with an escape character.'
+#     end
+#
+# Rendered HTML:
+#
+# >>>
+#   This is not verbatim text.
+#
+#     This is verbatim text, with an escape character \.
+#
+#   This is not a code block.
+#
+#     def foo
+#       'This is a code block with an escape character \.'
+#     end
+#
+# In typeface markup (italic, bold, or monofont),
+# an escape character is preserved unless it is immediately
+# followed by nested typeface markup.
+#
+# Example input:
+#
+#   This list is about escapes; it contains:
+#
+#   - <tt>Monofont text with unescaped nested _italic_</tt>.
+#   - <tt>Monofont text with escaped nested \_italic_</tt>.
+#   - <tt>Monofont text with an escape character \</tt>.
+#
+# Rendered HTML:
+#
+# >>>
+#   This list is about escapes; it contains:
+#
+#   - <tt>Monofont text with unescaped nested _italic_</tt>.
+#   - <tt>Monofont text with escaped nested \_italic_</tt>.
+#   - <tt>Monofont text with an escape character \ </tt>.
+#
+# In other text-bearing blocks
+# (paragraphs, block quotes, list items, headings):
+#
+# - A single escape character immediately followed by markup
+#   escapes the markup.
+# - A single escape character followed by whitespace is preserved.
+# - A single escape character anywhere else is ignored.
+# - A double escape character is rendered as a single backslash.
+#
+#   Example input:
+#
+#     This list is about escapes; it contains:
+#
+#     - An unescaped class name, RDoc, that will become a link.
+#     - An escaped class name, \RDoc, that will not become a link.
+#     - An escape character followed by whitespace \ .
+#     - An escape character \that is ignored.
+#     - A double escape character \\ that is rendered
+#       as a single backslash.
+#
+#   Rendered HTML:
+#
+#   >>>
+#     This list is about escapes; it contains:
+#
+#     - An unescaped class name, RDoc, that will become a link.
+#     - An escaped class name, \RDoc, that will not become a link.
+#     - An escape character followed by whitespace \ .
+#     - An escape character \that is ignored.
+#     - A double escape character \\ that is rendered
+#       as a single backslash.
+#
+# == Documentation Derived from Ruby Code
+#
+# [Class]
+#
+#   By default, \RDoc documents:
+#
+#   - \Class name.
+#   - Parent class.
+#   - Singleton methods.
+#   - Instance methods.
+#   - Aliases.
+#   - Constants.
+#   - Attributes.
+#
+# [Module]
+#
+#   By default, \RDoc documents:
+#
+#   - \Module name.
+#   - \Singleton methods.
+#   - Instance methods.
+#   - Aliases.
+#   - Constants.
+#   - Attributes.
+#
+# [Method]
+#
+#   By default, \RDoc documents:
+#
+#   - \Method name.
+#   - Arguments.
+#   - Yielded values.
+#
+#   See #method.
+#
+# [Alias]
+#
+#   By default, \RDoc documents:
+#
+#   - Alias name.
+#   - Aliased name.
+#
+#   See #dummy_instance_alias and #dummy_instance_method.
+#
+# [Constant]
+#
+#   By default, \RDoc documents:
+#
+#   - \Constant name.
+#
+#   See DUMMY_CONSTANT.
+#
+# [Attribute]
+#
+#   By default, \RDoc documents:
+#
+#   - Attribute name.
+#   - Attribute type (<tt>[R]</tt>, <tt>[W]</tt>, or <tt>[RW]</tt>)
+#
+#   See #dummy_attribute.
+#
+class RDoc::MarkupReference
+
+  class DummyClass; end
+  module DummyModule; end
+  def self.dummy_singleton_method(foo, bar); end
+  def dummy_instance_method(foo, bar); end;
+  alias dummy_instance_alias dummy_instance_method
+  attr_accessor :dummy_attribute
+  alias dummy_attribute_alias dummy_attribute
+  DUMMY_CONSTANT = ''
+
+  # :call-seq:
+  #   call_seq_directive(foo, bar)
+  #   Can be anything -> bar
+  #   Also anything more -> baz or bat
+  #
+  # The <tt>:call-seq:</tt> directive overrides the actual calling sequence
+  # found in the Ruby code.
+  #
+  # - It can specify anything at all.
+  # - It can have multiple calling sequences.
+  #
+  # This one includes <tt>Can be anything -> foo</tt>, which is nonsense.
+  #
+  # Note that the "arrow" is two characters, hyphen and right angle-bracket,
+  # which is made into a single character in the HTML.
+  #
+  # Click on the calling sequence to see the code.
+  #
+  # Here is the <tt>:call-seq:</tt> directive given for the method:
+  #
+  #   :call-seq:
+  #     call_seq_directive(foo, bar)
+  #     Can be anything -> bar
+  #     Also anything more -> baz or bat
+  #
+  def call_seq_directive
+    nil
+  end
+
+  # The <tt>:args:</tt> directive overrides the actual arguments found in the Ruby code.
+  #
+  # Click on the calling sequence to see the code.
+  #
+  def args_directive(foo, bar) # :args: baz
+    nil
+  end
+
+  # The <tt>:yields:</tt> directive overrides the actual yield found in the Ruby code.
+  #
+  # Click on the calling sequence to see the code.
+  #
+  def yields_directive(foo, bar) # :yields: 'bat'
+    yield 'baz'
+  end
+
+  # This method is documented only by \RDoc, except for these comments.
+  #
+  # Click on the calling sequence to see the code.
+  #
+  def method(foo, bar)
+    yield 'baz'
+  end
+
+end
diff --git a/doc/regexp.rdoc b/doc/regexp.rdoc
index 65d8cd46fa..92c7ecf66e 100644
--- a/doc/regexp.rdoc
+++ b/doc/regexp.rdoc
@@ -28,14 +28,21 @@ Specifically, <tt>/st/</tt> requires that the string contains the letter
 _s_ followed by the letter _t_, so it matches _haystack_, also.
 
 Note that any Regexp matching will raise a RuntimeError if timeout is set and
-exceeded. See "Timeout" section in detail.
+exceeded. See {"Timeout"}[#label-Timeout] section in detail.
+
+== \Regexp Interpolation
+
+A regexp may contain interpolated strings; trivially:
+
+  foo = 'bar'
+  /#{foo}/ # => /bar/
 
 == <tt>=~</tt> and Regexp#match
 
 Pattern matching may be achieved by using <tt>=~</tt> operator or Regexp#match
 method.
 
-=== <tt>=~</tt> operator
+=== <tt>=~</tt> Operator
 
 <tt>=~</tt> is Ruby's basic pattern-matching operator.  When one operand is a
 regular expression and the other is a string then the regular expression is
@@ -54,7 +61,7 @@ Using <tt>=~</tt> operator with a String and Regexp the <tt>$~</tt> global
 variable is set after a successful match.  <tt>$~</tt> holds a MatchData
 object. Regexp.last_match is equivalent to <tt>$~</tt>.
 
-=== Regexp#match method
+=== Regexp#match Method
 
 The #match method returns a MatchData object:
 
@@ -193,7 +200,7 @@ At least one uppercase character ('H'), at least one lowercase character
 
     "Hello".match(/[[:upper:]]+[[:lower:]]+l{2}o/) #=> #<MatchData "Hello">
 
-=== Greedy match
+=== Greedy Match
 
 Repetition is <i>greedy</i> by default: as many occurrences as possible
 are matched while still allowing the overall match to succeed. By
@@ -211,7 +218,7 @@ Both patterns below match the string. The first uses a greedy quantifier so
     /<.+>/.match("<a><b>")  #=> #<MatchData "<a><b>">
     /<.+?>/.match("<a><b>") #=> #<MatchData "<a>">
 
-=== Possessive match
+=== Possessive Match
 
 A quantifier followed by <tt>+</tt> matches <i>possessively</i>: once it
 has matched it does not backtrack. They behave like greedy quantifiers,
@@ -256,7 +263,7 @@ this backreference when doing substitution:
   "The cat sat in the hat".gsub(/[csh]at/, '\0s')
     # => "The cats sats in the hats"
 
-=== Named captures
+=== Named Captures
 
 Capture groups can be referred to by name when defined with the
 <tt>(?<</tt><i>name</i><tt>>)</tt> or <tt>(?'</tt><i>name</i><tt>')</tt>
@@ -543,12 +550,16 @@ characters, <i>anchoring</i> the match to a specific position.
 * <tt>(?<!</tt><i>pat</i><tt>)</tt> - <i>Negative lookbehind</i>
   assertion: ensures that the preceding characters do not match
   <i>pat</i>, but doesn't include those characters in the matched text
-* <tt>\K</tt> - Uses an positive lookbehind of the content preceding
-  <tt>\K</tt> in the regexp.  For example, the following two regexps are
-  almost equivalent:
 
-      /ab\Kc/
-      /(?<=ab)c/
+* <tt>\K</tt> - <i>Match reset</i>: the matched content preceding
+  <tt>\K</tt> in the regexp is excluded from the result.  For example,
+  the following two regexps are almost equivalent:
+
+      /ab\Kc/ =~ "abc"     #=> 0
+      /(?<=ab)c/ =~ "abc"  #=> 2
+
+  These match same string and <i>$&</i> equals <tt>"c"</tt>, while the
+  matched position is different.
 
   As are the following two regexps:
 
@@ -613,6 +624,11 @@ Options may also be used with <tt>Regexp.new</tt>:
     Regexp.new("abc # Comment", Regexp::EXTENDED)             #=> /abc # Comment/x
     Regexp.new("abc", Regexp::IGNORECASE | Regexp::MULTILINE) #=> /abc/mi
 
+    Regexp.new("abc", "i")           #=> /abc/i
+    Regexp.new("abc", "m")           #=> /abc/m
+    Regexp.new("abc # Comment", "x") #=> /abc # Comment/x
+    Regexp.new("abc", "im")          #=> /abc/mi
+
 == Free-Spacing Mode and Comments
 
 As mentioned above, the <tt>x</tt> option enables <i>free-spacing</i>
@@ -672,9 +688,10 @@ regexp's encoding can be explicitly fixed by supplying
        # raises Encoding::CompatibilityError: incompatible encoding regexp match
        #         (ISO-8859-1 regexp with UTF-8 string)
 
-== Special global variables
+== \Regexp Global Variables
 
 Pattern matching sets some global variables :
+
 * <tt>$~</tt> is equivalent to Regexp.last_match;
 * <tt>$&</tt> contains the complete matched text;
 * <tt>$`</tt> contains string before match;
@@ -764,7 +781,7 @@ with <i>a{0,29}</i>:
 
 == Timeout
 
-There are two APIs to set timeout. One is Timeout.timeout=, which is
+There are two APIs to set timeout. One is Regexp.timeout=, which is
 process-global configuration of timeout for Regexp matching.
 
     Regexp.timeout = 3
@@ -779,6 +796,6 @@ The other is timeout keyword of Regexp.new.
 
 When using Regexps to process untrusted input, you should use the timeout
 feature to avoid excessive backtracking. Otherwise, a malicious user can
-provide input to Regexp causing Denail-of-Service attack.
+provide input to Regexp causing Denial-of-Service attack.
 Note that the timeout is not set by default because an appropriate limit
 highly depends on an application requirement and context.
diff --git a/doc/standard_library.rdoc b/doc/standard_library.rdoc
index 1d3580163e..7c9938c5b0 100644
--- a/doc/standard_library.rdoc
+++ b/doc/standard_library.rdoc
@@ -31,12 +31,12 @@ Benchmark:: Provides methods to measure and report the time used to execute code
 Bundler:: Manage your Ruby application's gem dependencies
 CGI:: Support for the Common Gateway Interface protocol
 CSV:: Provides an interface to read and write CSV files and data
-DEBUGGER__:: Debugging functionality for Ruby
 Delegator:: Provides three abilities to delegate method calls to an object
 DidYouMean:: "Did you mean?" experience in Ruby
 DRb:: Distributed object system for Ruby
 English:: Provides references to special global variables with less cryptic names
 ERB:: An easy to use but powerful templating system for Ruby
+ErrorHighlight:: Highlight error location in your code
 FileUtils:: Several file utility methods for copying, moving, removing, etc
 Find:: This module supports top-down traversal of a set of file paths
 Forwardable:: Provides delegation of specified methods to a designated object
@@ -54,6 +54,8 @@ OpenURI:: An easy-to-use wrapper for Net::HTTP, Net::HTTPS and Net::FTP
 PP:: Provides a PrettyPrinter for Ruby objects
 PrettyPrinter:: Implements a pretty printing algorithm for readable structure
 PStore:: Implements a file based persistence mechanism based on a Hash
+Readline:: Wrapper for Readline extencion and Reline
+Reline:: GNU Readline and Editline by pure Ruby implementation.
 Resolv::  Thread-aware DNS resolver library in Ruby
 resolv-replace.rb:: Replace Socket DNS with Resolv
 RDoc:: Produces HTML and command-line documentation for Ruby
@@ -113,3 +115,4 @@ Matrix:: Represents a mathematical matrix.
 Prime:: Prime numbers and factorization library
 RBS:: RBS is a language to describe the structure of Ruby programs
 TypeProf:: A type analysis tool for Ruby code based on abstract interpretation
+DEBUGGER__:: Debugging functionality for Ruby
diff --git a/doc/strftime_formatting.rdoc b/doc/strftime_formatting.rdoc
new file mode 100644
index 0000000000..30a629bf68
--- /dev/null
+++ b/doc/strftime_formatting.rdoc
@@ -0,0 +1,527 @@
+== Formats for Dates and Times
+
+Several Ruby time-related classes have instance method +strftime+,
+which returns a formatted string representing all or part of a date or time:
+
+- Date#strftime.
+- DateTime#strftime.
+- Time#strftime.
+
+Each of these methods takes optional argument +format+,
+which has zero or more embedded _format_ _specifications_ (see below).
+
+Each of these methods returns the string resulting from replacing each
+format specification embedded in +format+ with a string form
+of one or more parts of the date or time.
+
+A simple example:
+
+  Time.now.strftime('%H:%M:%S') # => "14:02:07"
+
+A format specification has the form:
+
+  %[flags][width]conversion
+
+It consists of:
+
+- A leading percent character.
+- Zero or more _flags_ (each is a character).
+- An optional _width_ _specifier_ (an integer).
+- A _conversion_ _specifier_ (a character).
+
+Except for the leading percent character,
+the only required part is the conversion specifier, so we begin with that.
+
+=== Conversion Specifiers
+
+==== \Date (Year, Month, Day)
+
+- <tt>%Y</tt> - Year including century, zero-padded:
+
+    Time.now.strftime('%Y')        # => "2022"
+    Time.new(-1000).strftime('%Y') # => "-1000" # Before common era.
+    Time.new(10000).strftime('%Y') # => "10000" # Far future.
+    Time.new(10).strftime('%Y')    # => "0010"  # Zero-padded by default.
+
+- <tt>%y</tt> - Year without century, in range (0.99), zero-padded:
+
+    Time.now.strftime('%y')    # => "22"
+    Time.new(1).strftime('%y') # => "01" # Zero-padded by default.
+
+- <tt>%C</tt> - Century, zero-padded:
+
+    Time.now.strftime('%C')        # => "20"
+    Time.new(-1000).strftime('%C') # => "-10" # Before common era.
+    Time.new(10000).strftime('%C') # => "100" # Far future.
+    Time.new(100).strftime('%C')   # => "01"  # Zero-padded by default.
+
+- <tt>%m</tt> - Month of the year, in range (1..12), zero-padded:
+
+    Time.new(2022, 1).strftime('%m')  # => "01" # Zero-padded by default.
+    Time.new(2022, 12).strftime('%m') # => "12"
+
+- <tt>%B</tt> - Full month name, capitalized:
+
+    Time.new(2022, 1).strftime('%B')  # => "January"
+    Time.new(2022, 12).strftime('%B') # => "December"
+
+- <tt>%b</tt> - Abbreviated month name, capitalized:
+
+    Time.new(2022, 1).strftime('%b')  # => "Jan"
+    Time.new(2022, 12).strftime('%h') # => "Dec"
+
+- <tt>%h</tt> - Same as <tt>%b</tt>.
+
+- <tt>%d</tt> - Day of the month, in range (1..31), zero-padded:
+
+    Time.new(2002, 1, 1).strftime('%d')  # => "01"
+    Time.new(2002, 1, 31).strftime('%d') # => "31"
+
+- <tt>%e</tt> - Day of the month, in range (1..31), blank-padded:
+
+    Time.new(2002, 1, 1).strftime('%e')  # => " 1"
+    Time.new(2002, 1, 31).strftime('%e') # => "31"
+
+- <tt>%j</tt> - Day of the year, in range (1..366), zero-padded:
+
+    Time.new(2002, 1, 1).strftime('%j')   # => "001"
+    Time.new(2002, 12, 31).strftime('%j') # => "365"
+
+==== \Time (Hour, Minute, Second, Subsecond)
+
+- <tt>%H</tt> - Hour of the day, in range (0..23), zero-padded:
+
+    Time.new(2022, 1, 1, 1).strftime('%H')  # => "01"
+    Time.new(2022, 1, 1, 13).strftime('%H') # => "13"
+
+- <tt>%k</tt> - Hour of the day, in range (0..23), blank-padded:
+
+    Time.new(2022, 1, 1, 1).strftime('%k')  # => " 1"
+    Time.new(2022, 1, 1, 13).strftime('%k') # => "13"
+
+- <tt>%I</tt> - Hour of the day, in range (1..12), zero-padded:
+
+    Time.new(2022, 1, 1, 1).strftime('%I')  # => "01"
+    Time.new(2022, 1, 1, 13).strftime('%I') # => "01"
+
+- <tt>%l</tt> - Hour of the day, in range (1..12), blank-padded:
+
+    Time.new(2022, 1, 1, 1).strftime('%l')  # => " 1"
+    Time.new(2022, 1, 1, 13).strftime('%l') # => " 1"
+
+- <tt>%P</tt> - Meridian indicator, lowercase:
+
+    Time.new(2022, 1, 1, 1).strftime('%P')  # => "am"
+    Time.new(2022, 1, 1, 13).strftime('%P') # => "pm"
+
+- <tt>%p</tt> - Meridian indicator, uppercase:
+
+    Time.new(2022, 1, 1, 1).strftime('%p')  # => "AM"
+    Time.new(2022, 1, 1, 13).strftime('%p') # => "PM"
+
+- <tt>%M</tt> - Minute of the hour, in range (0..59), zero-padded:
+
+    Time.new(2022, 1, 1, 1, 0, 0).strftime('%M') # => "00"
+
+- <tt>%S</tt> - Second of the minute in range (0..59), zero-padded:
+
+    Time.new(2022, 1, 1, 1, 0, 0, 0).strftime('%S') # => "00"
+
+- <tt>%L</tt> - Millisecond of the second, in range (0..999), zero-padded:
+
+    Time.new(2022, 1, 1, 1, 0, 0, 0).strftime('%L') # => "000"
+
+- <tt>%N</tt> - Fractional seconds, default width is 9 digits (nanoseconds):
+
+    t = Time.now       # => 2022-06-29 07:10:20.3230914 -0500
+    t.strftime('%N')   # => "323091400"                  # Default.
+
+  Use {width specifiers}[rdoc-ref:strftime_formatting.rdoc@Width+Specifiers]
+  to adjust units:
+
+      t.strftime('%3N')  # => "323"                      # Milliseconds.
+      t.strftime('%6N')  # => "323091"                   # Microseconds.
+      t.strftime('%9N')  # => "323091400"                # Nanoseconds.
+      t.strftime('%12N') # => "323091400000"             # Picoseconds.
+      t.strftime('%15N') # => "323091400000000"          # Femptoseconds.
+      t.strftime('%18N') # => "323091400000000000"       # Attoseconds.
+      t.strftime('%21N') # => "323091400000000000000"    # Zeptoseconds.
+      t.strftime('%24N') # => "323091400000000000000000" # Yoctoseconds.
+
+- <tt>%s</tt> - Number of seconds since the epoch:
+
+    Time.now.strftime('%s') # => "1656505136"
+
+==== Timezone
+
+- <tt>%z</tt> - Timezone as hour and minute offset from UTC:
+
+    Time.now.strftime('%z') # => "-0500"
+
+- <tt>%Z</tt> - Timezone name (platform-dependent):
+
+    Time.now.strftime('%Z') # => "Central Daylight Time"
+
+==== Weekday
+
+- <tt>%A</tt> - Full weekday name:
+
+    Time.now.strftime('%A') # => "Wednesday"
+
+- <tt>%a</tt> - Abbreviated weekday name:
+
+    Time.now.strftime('%a') # => "Wed"
+
+- <tt>%u</tt> - Day of the week, in range (1..7), Monday is 1:
+
+    t = Time.new(2022, 6, 26) # => 2022-06-26 00:00:00 -0500
+    t.strftime('%a')          # => "Sun"
+    t.strftime('%u')          # => "7"
+
+- <tt>%w</tt> - Day of the week, in range (0..6), Sunday is 0:
+
+    t = Time.new(2022, 6, 26) # => 2022-06-26 00:00:00 -0500
+    t.strftime('%a')          # => "Sun"
+    t.strftime('%w')          # => "0"
+
+==== Week Number
+
+- <tt>%U</tt> - Week number of the year, in range (0..53), zero-padded,
+  where each week begins on a Sunday:
+
+    t = Time.new(2022, 6, 26) # => 2022-06-26 00:00:00 -0500
+    t.strftime('%a')          # => "Sun"
+    t.strftime('%U')          # => "26"
+
+- <tt>%W</tt> - Week number of the year, in range (0..53), zero-padded,
+  where each week begins on a Monday:
+
+    t = Time.new(2022, 6, 26) # => 2022-06-26 00:00:00 -0500
+    t.strftime('%a')          # => "Sun"
+    t.strftime('%W')          # => "25"
+
+==== Week Dates
+
+See {ISO 8601 week dates}[https://en.wikipedia.org/wiki/ISO_8601#Week_dates].
+
+    t0 = Time.new(2023, 1, 1) # => 2023-01-01 00:00:00 -0600
+    t1 = Time.new(2024, 1, 1) # => 2024-01-01 00:00:00 -0600
+
+- <tt>%G</tt> - Week-based year:
+
+    t0.strftime('%G') # => "2022"
+    t1.strftime('%G') # => "2024"
+
+- <tt>%g</tt> - Week-based year without century, in range (0..99), zero-padded:
+
+    t0.strftime('%g') # => "22"
+    t1.strftime('%g') # => "24"
+
+- <tt>%V</tt> - Week number of the week-based year, in range (1..53),
+  zero-padded:
+
+    t0.strftime('%V') # => "52"
+    t1.strftime('%V') # => "01"
+
+==== Literals
+
+- <tt>%n</tt> - Newline character "\n":
+
+    Time.now.strftime('%n') # => "\n"
+
+- <tt>%t</tt> - Tab character "\t":
+
+    Time.now.strftime('%t') # => "\t"
+
+- <tt>%%</tt> - Percent character '%':
+
+    Time.now.strftime('%%') # => "%"
+
+==== Shorthand Conversion Specifiers
+
+Each shorthand specifier here is shown with its corresponding
+longhand specifier.
+
+- <tt>%c</tt> - \Date and time:
+
+    Time.now.strftime('%c')             # => "Wed Jun 29 08:01:41 2022"
+    Time.now.strftime('%a %b %e %T %Y') # => "Wed Jun 29 08:02:07 2022"
+
+- <tt>%D</tt> - \Date:
+
+    Time.now.strftime('%D')       # => "06/29/22"
+    Time.now.strftime('%m/%d/%y') # => "06/29/22"
+
+- <tt>%F</tt> - ISO 8601 date:
+
+    Time.now.strftime('%F')       # => "2022-06-29"
+    Time.now.strftime('%Y-%m-%d') # => "2022-06-29"
+
+- <tt>%v</tt> - VMS date:
+
+    Time.now.strftime('%v')         # => "29-JUN-2022"
+    Time.now.strftime('%e-%^b-%4Y') # => "29-JUN-2022"
+
+- <tt>%x</tt> - Same as <tt>%D</tt>.
+
+- <tt>%X</tt> - Same as <tt>%T</tt>.
+
+- <tt>%r</tt> - 12-hour time:
+
+    Time.new(2022, 1, 1, 1).strftime('%r')           # => "01:00:00 AM"
+    Time.new(2022, 1, 1, 1).strftime('%I:%M:%S %p')  # => "01:00:00 AM"
+    Time.new(2022, 1, 1, 13).strftime('%r')          # => "01:00:00 PM"
+    Time.new(2022, 1, 1, 13).strftime('%I:%M:%S %p') # => "01:00:00 PM"
+
+- <tt>%R</tt> - 24-hour time:
+
+    Time.new(2022, 1, 1, 1).strftime('%R')     # => "01:00"
+    Time.new(2022, 1, 1, 1).strftime('%H:%M')  # => "01:00"
+    Time.new(2022, 1, 1, 13).strftime('%R')    # => "13:00"
+    Time.new(2022, 1, 1, 13).strftime('%H:%M') # => "13:00"
+
+- <tt>%T</tt> - 24-hour time:
+
+    Time.new(2022, 1, 1, 1).strftime('%T')        # => "01:00:00"
+    Time.new(2022, 1, 1, 1).strftime('%H:%M:%S')  # => "01:00:00"
+    Time.new(2022, 1, 1, 13).strftime('%T')       # => "13:00:00"
+    Time.new(2022, 1, 1, 13).strftime('%H:%M:%S') # => "13:00:00"
+
+- <tt>%+</tt> (not supported in Time#strftime) - \Date and time:
+
+    DateTime.now.strftime('%+')
+    # => "Wed Jun 29 08:31:53 -05:00 2022"
+    DateTime.now.strftime('%a %b %e %H:%M:%S %Z %Y')
+    # => "Wed Jun 29 08:32:18 -05:00 2022"
+
+=== Flags
+
+Flags may affect certain formatting specifications.
+
+Multiple flags may be given with a single conversion specified;
+order does not matter.
+
+==== Padding Flags
+
+- <tt>0</tt> - Pad with zeroes:
+
+    Time.new(10).strftime('%0Y') # => "0010"
+
+- <tt>_</tt> - Pad with blanks:
+
+    Time.new(10).strftime('%_Y') # => "  10"
+
+- <tt>-</tt> - Don't pad:
+
+    Time.new(10).strftime('%-Y') # => "10"
+
+==== Casing Flags
+
+- <tt>^</tt> - Upcase result:
+
+    Time.new(2022, 1).strftime('%B')  # => "January" # No casing flag.
+    Time.new(2022, 1).strftime('%^B') # => "JANUARY"
+
+- <tt>#</tt> - Swapcase result:
+
+    Time.now.strftime('%p')  # => "AM"
+    Time.now.strftime('%^p') # => "AM"
+    Time.now.strftime('%#p') # => "am"
+
+==== Timezone Flags
+
+- <tt>:</tt> - Put timezone as colon-separated hours and minutes:
+
+    Time.now.strftime('%:z')  # => "-05:00"
+
+- <tt>::</tt> - Put timezone as colon-separated hours, minutes, and seconds:
+
+    Time.now.strftime('%::z') # => "-05:00:00"
+
+=== Width Specifiers
+
+The integer width specifier gives a minimum width for the returned string:
+
+  Time.new(2002).strftime('%Y')       # => "2002"     # No width specifier.
+  Time.new(2002).strftime('%10Y')     # => "0000002002"
+  Time.new(2002, 12).strftime('%B')   # => "December" # No width specifier.
+  Time.new(2002, 12).strftime('%10B') # => "  December"
+  Time.new(2002, 12).strftime('%3B')  # => "December" # Ignored if too small.
+
+== Specialized Format Strings
+
+Here are a few specialized format strings,
+each based on an external standard.
+
+=== HTTP Format
+
+The HTTP date format is based on
+{RFC 2616}[https://datatracker.ietf.org/doc/html/rfc2616],
+and treats dates in the format <tt>'%a, %d %b %Y %T GMT'</tt>:
+
+  d = Date.new(2001, 2, 3) # => #<Date: 2001-02-03>
+  # Return HTTP-formatted string.
+  httpdate = d.httpdate    # => "Sat, 03 Feb 2001 00:00:00 GMT"
+  # Return new date parsed from HTTP-formatted string.
+  Date.httpdate(httpdate)  # => #<Date: 2001-02-03>
+  # Return hash parsed from HTTP-formatted string.
+  Date._httpdate(httpdate)
+  # => {:wday=>6, :mday=>3, :mon=>2, :year=>2001, :hour=>0, :min=>0, :sec=>0, :zone=>"GMT", :offset=>0}
+
+=== RFC 3339 Format
+
+The RFC 3339 date format is based on
+{RFC 3339}[https://datatracker.ietf.org/doc/html/rfc3339]:
+
+  d = Date.new(2001, 2, 3) # => #<Date: 2001-02-03>
+  # Return 3339-formatted string.
+  rfc3339 = d.rfc3339      # => "2001-02-03T00:00:00+00:00"
+  # Return new date parsed from 3339-formatted string.
+  Date.rfc3339(rfc3339)    # => #<Date: 2001-02-03>
+  # Return hash parsed from 3339-formatted string.
+  Date._rfc3339(rfc3339)
+  # => {:year=>2001, :mon=>2, :mday=>3, :hour=>0, :min=>0, :sec=>0, :zone=>"+00:00", :offset=>0}
+
+=== RFC 2822 Format
+
+The RFC 2822 date format is based on
+{RFC 2822}[https://datatracker.ietf.org/doc/html/rfc2822],
+and treats dates in the format <tt>'%a, %-d %b %Y %T %z'</tt>]:
+
+  d = Date.new(2001, 2, 3) # => #<Date: 2001-02-03>
+  # Return 2822-formatted string.
+  rfc2822 = d.rfc2822      # => "Sat, 3 Feb 2001 00:00:00 +0000"
+  # Return new date parsed from 2822-formatted string.
+  Date.rfc2822(rfc2822)    # => #<Date: 2001-02-03>
+  # Return hash parsed from 2822-formatted string.
+  Date._rfc2822(rfc2822)
+  # => {:wday=>6, :mday=>3, :mon=>2, :year=>2001, :hour=>0, :min=>0, :sec=>0, :zone=>"+0000", :offset=>0}
+
+=== JIS X 0301 Format
+
+The JIS X 0301 format includes the
+{Japanese era name}[https://en.wikipedia.org/wiki/Japanese_era_name],
+and treats dates in the format <tt>'%Y-%m-%d'</tt>
+with the first letter of the romanized era name prefixed:
+
+  d = Date.new(2001, 2, 3) # => #<Date: 2001-02-03>
+  # Return 0301-formatted string.
+  jisx0301 = d.jisx0301    # => "H13.02.03"
+  # Return new date parsed from 0301-formatted string.
+  Date.jisx0301(jisx0301)  # => #<Date: 2001-02-03>
+  # Return hash parsed from 0301-formatted string.
+  Date._jisx0301(jisx0301) # => {:year=>2001, :mon=>2, :mday=>3}
+
+=== ISO 8601 Format Specifications
+
+This section shows format specifications that are compatible with
+{ISO 8601}[https://en.wikipedia.org/wiki/ISO_8601].
+Details for various formats may be seen at the links.
+
+Examples in this section assume:
+
+  t = Time.now # => 2022-06-29 16:49:25.465246 -0500
+
+==== Dates
+
+See {ISO 8601 dates}[https://en.wikipedia.org/wiki/ISO_8601#Dates].
+
+- {Years}[https://en.wikipedia.org/wiki/ISO_8601#Years]:
+
+  - Basic year (+YYYY+):
+
+      t.strftime('%Y') # => "2022"
+
+  - Expanded year (<tt>±YYYYY</tt>):
+
+      t.strftime('+%5Y') # => "+02022"
+      t.strftime('-%5Y') # => "-02022"
+
+- {Calendar dates}[https://en.wikipedia.org/wiki/ISO_8601#Calendar_dates]:
+
+  - Basic date (+YYYYMMDD+):
+
+      t.strftime('%Y%m%d') # => "20220629"
+
+  - Extended date (<tt>YYYY-MM-DD</tt>):
+
+      t.strftime('%Y-%m-%d') # => "2022-06-29"
+
+  - Reduced extended date (<tt>YYYY-MM</tt>):
+
+      t.strftime('%Y-%m') # => "2022-06"
+
+- {Week dates}[https://en.wikipedia.org/wiki/ISO_8601#Week_dates]:
+
+  - Basic date (+YYYYWww+ or +YYYYWwwD+):
+
+      t.strftime('%Y%Ww')   # => "202226w"
+      t.strftime('%Y%Ww%u') # => "202226w3"
+
+  - Extended date (<tt>YYYY-Www</tt> or <tt>YYYY-Www-D<tt>):
+
+      t.strftime('%Y-%Ww')    # => "2022-26w"
+      t.strftime('%Y-%Ww-%u') # => "2022-26w-3"
+
+- {Ordinal dates}[https://en.wikipedia.org/wiki/ISO_8601#Ordinal_dates]:
+
+  - Basic date (+YYYYDDD+):
+
+      t.strftime('%Y%j') # => "2022180"
+
+  - Extended date (<tt>YYYY-DDD</tt>):
+
+      t.strftime('%Y-%j') # => "2022-180"
+
+==== Times
+
+See {ISO 8601 times}[https://en.wikipedia.org/wiki/ISO_8601#Times].
+
+- Times:
+
+  - Basic time (+Thhmmss.sss+, +Thhmmss+, +Thhmm+, or +Thh+):
+
+      t.strftime('T%H%M%S.%L') # => "T164925.465"
+      t.strftime('T%H%M%S')    # => "T164925"
+      t.strftime('T%H%M')      # => "T1649"
+      t.strftime('T%H')        # => "T16"
+
+  - Extended time (+Thh:mm:ss.sss+, +Thh:mm:ss+, or +Thh:mm+):
+
+      t.strftime('T%H:%M:%S.%L') # => "T16:49:25.465"
+      t.strftime('T%H:%M:%S')    # => "T16:49:25"
+      t.strftime('T%H:%M')       # => "T16:49"
+
+- {Time zone designators}[https://en.wikipedia.org/wiki/ISO_8601#Time_zone_designators]:
+
+  - Timezone (+time+ represents a valid time,
+    +hh+ represents a valid 2-digit hour,
+    and +mm+ represents a valid 2-digit minute):
+
+    - Basic timezone (<tt>time±hhmm</tt>, <tt>time±hh</tt>, or +timeZ+):
+
+        t.strftime('T%H%M%S%z')              # => "T164925-0500"
+        t.strftime('T%H%M%S%z').slice(0..-3) # => "T164925-05"
+        t.strftime('T%H%M%SZ')               # => "T164925Z"
+
+    - Extended timezone (<tt>time±hh:mm</tt>):
+
+        t.strftime('T%H:%M:%S%z') # => "T16:49:25-0500"
+
+  - See also:
+
+    - {Local time (unqualified)}[https://en.wikipedia.org/wiki/ISO_8601#Local_time_(unqualified)].
+    - {Coordinated Universal Time (UTC)}[https://en.wikipedia.org/wiki/ISO_8601#Coordinated_Universal_Time_(UTC)].
+    - {Time offsets from UTC}[https://en.wikipedia.org/wiki/ISO_8601#Time_offsets_from_UTC].
+
+==== Combined \Date and \Time
+
+See {ISO 8601 Combined date and time representations}[https://en.wikipedia.org/wiki/ISO_8601#Combined_date_and_time_representations].
+
+An ISO 8601 combined date and time representation may be any
+ISO 8601 date and any ISO 8601 time,
+separated by the letter +T+.
+
+For the relevant +strftime+ formats, see
+{Dates}[rdoc-ref:strftime_formatting.rdoc@Dates]
+and {Times}[rdoc-ref:strftime_formatting.rdoc@Times] above.
diff --git a/doc/string/start_with_p.rdoc b/doc/string/start_with_p.rdoc
index 1cfed76296..5d1f9f9543 100644
--- a/doc/string/start_with_p.rdoc
+++ b/doc/string/start_with_p.rdoc
@@ -1,6 +1,6 @@
 Returns whether +self+ starts with any of the given +string_or_regexp+.
 
-Matches patterns against the beginning of+self+.
+Matches patterns against the beginning of +self+.
 For each given +string_or_regexp+, the pattern is:
 
 - +string_or_regexp+ itself, if it is a Regexp.
diff --git a/doc/symbol/casecmp.rdoc b/doc/symbol/casecmp.rdoc
new file mode 100644
index 0000000000..9c286070b7
--- /dev/null
+++ b/doc/symbol/casecmp.rdoc
@@ -0,0 +1,27 @@
+Like Symbol#<=>, but case-insensitive;
+equivalent to <tt>self.to_s.casecmp(object.to_s)</tt>:
+
+  lower = :abc
+  upper = :ABC
+  upper.casecmp(lower) # => 0
+  lower.casecmp(lower) # => 0
+  lower.casecmp(upper) # => 0
+
+Returns nil if +self+ and +object+ have incompatible encodings,
+or if +object+ is not a symbol:
+
+  sym = 'äöü'.encode("ISO-8859-1").to_sym
+  other_sym = 'ÄÖÜ'
+  sym.casecmp(other_sym) # => nil
+  :foo.casecmp(2)        # => nil
+
+Unlike Symbol#casecmp?,
+case-insensitivity does not work for characters outside of 'A'..'Z' and 'a'..'z':
+
+  lower = :äöü
+  upper = :ÄÖÜ
+  upper.casecmp(lower) # => -1
+  lower.casecmp(lower) # => 0
+  lower.casecmp(upper) # => 1
+
+Related: Symbol#casecmp?, String#casecmp.
diff --git a/doc/symbol/casecmp_p.rdoc b/doc/symbol/casecmp_p.rdoc
new file mode 100644
index 0000000000..7102b54289
--- /dev/null
+++ b/doc/symbol/casecmp_p.rdoc
@@ -0,0 +1,26 @@
+Returns +true+ if +self+ and +object+ are equal after Unicode case folding,
+otherwise +false+:
+
+  lower = :abc
+  upper = :ABC
+  upper.casecmp?(lower) # => true
+  lower.casecmp?(lower) # => true
+  lower.casecmp?(upper) # => true
+
+Returns nil if +self+ and +object+ have incompatible encodings,
+or if +object+ is not a symbol:
+
+  sym = 'äöü'.encode("ISO-8859-1").to_sym
+  other_sym = 'ÄÖÜ'
+  sym.casecmp?(other_sym) # => nil
+  :foo.casecmp?(2)        # => nil
+
+Unlike Symbol#casecmp, works for characters outside of 'A'..'Z' and 'a'..'z':
+
+  lower = :äöü
+  upper = :ÄÖÜ
+  upper.casecmp?(lower) # => true
+  lower.casecmp?(lower) # => true
+  lower.casecmp?(upper) # => true
+
+Related: Symbol#casecmp, String#casecmp?.
diff --git a/doc/syntax/assignment.rdoc b/doc/syntax/assignment.rdoc
index a1806e4c48..1321bbf3ac 100644
--- a/doc/syntax/assignment.rdoc
+++ b/doc/syntax/assignment.rdoc
@@ -8,6 +8,9 @@ example assigns the number five to the local variable +v+:
 Assignment creates a local variable if the variable was not previously
 referenced.
 
+An assignment expression result is always the assigned value, including
+{assignment methods}[rdoc-ref:syntax/assignment.rdoc@Assignment+Methods].
+
 == Local Variable Names
 
 A local variable name must start with a lowercase US-ASCII letter or a
@@ -342,6 +345,9 @@ This prints:
   local_variables:
   @value: 42
 
+Note that the value returned by an assignment method is ignored whatever,
+since an assignment expression result is always the assignment value.
+
 == Abbreviated Assignment
 
 You can mix several of the operators and assignment.  To add 1 to an object
diff --git a/doc/syntax/literals.rdoc b/doc/syntax/literals.rdoc
index 32fe5110ce..b641433249 100644
--- a/doc/syntax/literals.rdoc
+++ b/doc/syntax/literals.rdoc
@@ -90,15 +90,36 @@ point numbers as well.
 
 === \Rational Literals
 
-You can write a Rational number as follows (suffixed +r+):
+You can write a Rational literal using a special suffix, <tt>'r'</tt>.
 
-  12r         #=> (12/1)
-  12.3r       #=> (123/10)
-
-A \Rational number is exact, whereas a \Float number may be inexact.
+Examples:
 
-  0.1r + 0.2r #=> (3/10)
-  0.1 + 0.2   #=> 0.30000000000000004
+  1r       # => (1/1)
+  2/3r     # => (2/3)   # With denominator.
+  -1r      # => (-1/1)  # With signs.
+  -2/3r    # => (-2/3)
+  2/-3r    # => (-2/3)
+  -2/-3r   # => (2/3)
+  +1/+3r   # => (1/3)
+  1.2r     # => (6/5)   # With fractional part.
+  1_1/2_1r # => (11/21) # With embedded underscores.
+  2/4r     # => (1/2)   # Automatically reduced.
+
+Syntax:
+
+  <rational-literal> = <numerator> [ '/' <denominator> ] 'r'
+  <numerator> = [ <sign> ] <digits> [ <fractional-part> ]
+  <fractional-part> = '.' <digits>
+  <denominator> = [ sign ] <digits>
+  <sign> = '-' | '+'
+  <digits> = <digit> { <digit> | '_' <digit> }
+  <digit> = '0' | '1' | '2' | '3' | '4' | '5' | '6' | '7' | '8' | '9'
+
+Note this, which is parsed as \Float numerator <tt>1.2</tt>
+divided by \Rational denominator <tt>3r</tt>,
+resulting in a \Float:
+
+  1.2/3r  # => 0.39999999999999997
 
 === \Complex Literals
 
@@ -256,6 +277,12 @@ the content.  Note that empty lines and lines consisting solely of literal tabs
 and spaces will be ignored for the purposes of determining indentation, but
 escaped tabs and spaces are considered non-indentation characters.
 
+For the purpose of measuring an indentation, a horizontal tab is regarded as a
+sequence of one to eight spaces such that the column position corresponding to
+its end is a multiple of eight.  The amount to be removed is counted in terms
+of the number of spaces.  If the boundary appears in the middle of a tab, that
+tab is not removed.
+
 A heredoc allows interpolation and escaped characters.  You may disable
 interpolation and escaping by surrounding the opening identifier with single
 quotes:
@@ -381,15 +408,15 @@ on the methods you need to implement.
 
 == \Regexp Literals
 
-A regular expression is created using "/":
+A regular expression may be created using leading and trailing
+slash (<tt>'/'</tt>) characters:
 
-  /my regular expression/
+  re = /foo/ # => /foo/
+  re.class   # => Regexp
 
-The regular expression may be followed by flags which adjust the matching
-behavior of the regular expression.  The "i" flag makes the regular expression
-case-insensitive:
-
-  /my regular expression/i
+The trailing slash may be followed by one or more _flag_ characters
+that modify the behavior.
+See {Regexp options}[rdoc-ref:Regexp@Options] for details.
 
 Interpolation may be used inside regular expressions along with escaped
 characters.  Note that a regular expression may require additional escaped
@@ -420,10 +447,10 @@ This proc will add one to its argument.
 Each of the literals in described in this section
 may use these paired delimiters:
 
-* <tt>[</tt> and </tt>]</tt>.
-* <tt>(</tt> and </tt>)</tt>.
-* <tt>{</tt> and </tt>}</tt>.
-* <tt><</tt> and </tt>></tt>.
+* <tt>[</tt> and <tt>]</tt>.
+* <tt>(</tt> and <tt>)</tt>.
+* <tt>{</tt> and <tt>}</tt>.
+* <tt><</tt> and <tt>></tt>.
 * Any other character, as both beginning and ending delimiters.
 
 These are demonstrated in the next section.
@@ -482,13 +509,23 @@ You can write a symbol with <tt>%s</tt>:
 
 === <tt>%r</tt>: Regexp Literals
 
-You can write a regular expression with <tt>%r</tt>:
+You can write a regular expression with <tt>%r</tt>;
+the character used as the leading and trailing delimiter
+may be (almost) any character:
+
+  %r/foo/             # => /foo/
+  %r:name/value pair: # => /name\/value pair/
+
+A few "symmetrical" character pairs may be used as delimiters:
 
-  r = %r[foo\sbar]   # => /foo\sbar/
-  'foo bar'.match(r) # => #<MatchData "foo bar">
-  r = %r[foo\sbar]i  # => /foo\sbar/i
-  'FOO BAR'.match(r) # => #<MatchData "FOO BAR">
+  %r[foo] # => /foo/
+  %r{foo} # => /foo/
+  %r(foo) # => /foo/
+  %r<foo> # => /foo/
 
+The trailing delimiter may be followed by one or more _flag_ characters
+that modify the behavior.
+See {Regexp options}[rdoc-ref:Regexp@Options] for details.
 
 === <tt>%x</tt>: Backtick Literals
 
diff --git a/doc/syntax/modules_and_classes.rdoc b/doc/syntax/modules_and_classes.rdoc
index 6122f6e08e..024815a5a6 100644
--- a/doc/syntax/modules_and_classes.rdoc
+++ b/doc/syntax/modules_and_classes.rdoc
@@ -155,8 +155,8 @@ Ruby has three types of visibility.  The default is +public+.  A public method
 may be called from any other object.
 
 The second visibility is +protected+.  When calling a protected method the
-sender must be a subclass of the receiver or the receiver must be a subclass of
-the sender.  Otherwise a NoMethodError will be raised.
+sender must inherit the Class or Module which defines the method.  Otherwise a
+NoMethodError will be raised.
 
 Protected visibility is most frequently used to define <code>==</code> and
 other comparison methods where the author does not wish to expose an object's
diff --git a/doc/time/in.rdoc b/doc/time/in.rdoc
deleted file mode 100644
index f47db76a35..0000000000
--- a/doc/time/in.rdoc
+++ /dev/null
@@ -1,7 +0,0 @@
-- <tt>in: zone</tt>: a timezone _zone_, which may be:
-  - A string offset from UTC.
-  - A single letter offset from UTC, in the range <tt>'A'..'Z'</tt>,
-    <tt>'J'</tt> (the so-called military timezone) excluded.
-  - An integer number of seconds.
-  - A timezone object;
-    see {Timezone Argument}[#class-Time-label-Timezone+Argument] for details.
diff --git a/doc/time/mon-min.rdoc b/doc/time/mon-min.rdoc
deleted file mode 100644
index 5bd430c74a..0000000000
--- a/doc/time/mon-min.rdoc
+++ /dev/null
@@ -1,8 +0,0 @@
-- +month+: a month value, which may be:
-  - An integer month in the range <tt>1..12</tt>.
-  - A 3-character string that matches regular expression
-    <tt>/jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec/i</tt>.
-- +day+: an integer day in the range <tt>1..31</tt>
-  (less than 31 for some months).
-- +hour+: an integer hour in the range <tt>0..23</tt>.
-- +min+: an integer minute in the range <tt>0..59</tt>.
diff --git a/doc/time/msec.rdoc b/doc/time/msec.rdoc
deleted file mode 100644
index ce5d1e6145..0000000000
--- a/doc/time/msec.rdoc
+++ /dev/null
@@ -1,2 +0,0 @@
-- +msec+ is the number of milliseconds (Integer, Float, or Rational)
-  in the range <tt>0..1000</tt>.
diff --git a/doc/time/nsec.rdoc b/doc/time/nsec.rdoc
deleted file mode 100644
index a2dfe2d608..0000000000
--- a/doc/time/nsec.rdoc
+++ /dev/null
@@ -1,2 +0,0 @@
-- +nsec+ is the number of nanoseconds (Integer, Float, or Rational)
-  in the range <tt>0..1000000000</tt>.
diff --git a/doc/time/sec.rdoc b/doc/time/sec.rdoc
deleted file mode 100644
index 049c712110..0000000000
--- a/doc/time/sec.rdoc
+++ /dev/null
@@ -1,2 +0,0 @@
-- +sec+ is the number of seconds (Integer, Float, or Rational)
-  in the range <tt>0..60</tt>.
diff --git a/doc/time/sec_i.rdoc b/doc/time/sec_i.rdoc
deleted file mode 100644
index 99c8eddc65..0000000000
--- a/doc/time/sec_i.rdoc
+++ /dev/null
@@ -1 +0,0 @@
-- +isec_i+ is the integer number of seconds in the range <tt>0..60</tt>.
diff --git a/doc/time/usec.rdoc b/doc/time/usec.rdoc
deleted file mode 100644
index bb5a46419a..0000000000
--- a/doc/time/usec.rdoc
+++ /dev/null
@@ -1,2 +0,0 @@
-- +usec+ is the number of microseconds (Integer, Float, or Rational)
-  in the range <tt>0..1000000</tt>.
diff --git a/doc/time/year.rdoc b/doc/time/year.rdoc
deleted file mode 100644
index 2222b830d7..0000000000
--- a/doc/time/year.rdoc
+++ /dev/null
@@ -1 +0,0 @@
-- +year+: an integer year.
diff --git a/doc/time/zone_and_in.rdoc b/doc/time/zone_and_in.rdoc
deleted file mode 100644
index e09e22874b..0000000000
--- a/doc/time/zone_and_in.rdoc
+++ /dev/null
@@ -1,8 +0,0 @@
-- +zone+: a timezone, which may be:
-  - A string offset from UTC.
-  - A single letter offset from UTC, in the range <tt>'A'..'Z'</tt>,
-    <tt>'J'</tt> (the so-called military timezone) excluded.
-  - An integer number of seconds.
-  - A timezone object;
-    see {Timezone Argument}[#class-Time-label-Timezone+Argument] for details.
-- <tt>in: zone</tt>: a timezone _zone_, which may be as above.
diff --git a/doc/timezones.rdoc b/doc/timezones.rdoc
new file mode 100644
index 0000000000..c3aae88fde
--- /dev/null
+++ b/doc/timezones.rdoc
@@ -0,0 +1,108 @@
+== Timezones
+
+=== Timezone Specifiers
+
+Certain \Time methods accept arguments that specify timezones:
+
+- Time.at: keyword argument +in:+.
+- Time.new: positional argument +zone+ or keyword argument +in:+.
+- Time.now: keyword argument +in:+.
+- Time#getlocal: positional argument +zone+.
+- Time#localtime: positional argument +zone+.
+
+The value given with any of these must be one of the following
+(each detailed below):
+
+- {Hours/minutes offset}[rdoc-ref:timezones.rdoc@Hours-2FMinutes+Offsets].
+- {Single-letter offset}[rdoc-ref:timezones.rdoc@Single-Letter+Offsets].
+- {Integer offset}[rdoc-ref:timezones.rdoc@Integer+Offsets].
+- {Timezone object}[rdoc-ref:timezones.rdoc@Timezone+Objects].
+
+==== Hours/Minutes Offsets
+
+The zone value may be a string offset from UTC
+in the form <tt>'+HH:MM'</tt> or <tt>'-HH:MM'</tt>,
+where:
+
+- +HH+ is the 2-digit hour in the range <tt>0..23</tt>.
+- +MM+ is the 2-digit minute in the range <tt>0..59</tt>.
+
+Examples:
+
+  t = Time.utc(2000, 1, 1, 20, 15, 1) # => 2000-01-01 20:15:01 UTC
+  Time.at(t, in: '-23:59')            # => 1999-12-31 20:16:01 -2359
+  Time.at(t, in: '+23:59')            # => 2000-01-02 20:14:01 +2359
+
+==== Single-Letter Offsets
+
+The zone value may be a  letter in the range <tt>'A'..'I'</tt>
+or <tt>'K'..'Z'</tt>;
+see {List of military time zones}[https://en.wikipedia.org/wiki/List_of_military_time_zones]:
+
+  t = Time.utc(2000, 1, 1, 20, 15, 1) # => 2000-01-01 20:15:01 UTC
+  Time.at(t, in: 'A')                 # => 2000-01-01 21:15:01 +0100
+  Time.at(t, in: 'I')                 # => 2000-01-02 05:15:01 +0900
+  Time.at(t, in: 'K')                 # => 2000-01-02 06:15:01 +1000
+  Time.at(t, in: 'Y')                 # => 2000-01-01 08:15:01 -1200
+  Time.at(t, in: 'Z')                 # => 2000-01-01 20:15:01 UTC
+
+==== \Integer Offsets
+
+The zone value may be an integer number of seconds
+in the range <tt>-86399..86399</tt>:
+
+  t = Time.utc(2000, 1, 1, 20, 15, 1) # => 2000-01-01 20:15:01 UTC
+  Time.at(t, in: -86399)              # => 1999-12-31 20:15:02 -235959
+  Time.at(t, in: 86399)               # => 2000-01-02 20:15:00 +235959
+
+==== Timezone Objects
+
+In most cases, the zone value may be an object
+responding to certain timezone methods.
+
+\Exceptions (timezone object not allowed):
+
+- Time.new with positional argument +zone+.
+- Time.now with keyword argument +in:+.
+
+The timezone methods are:
+
+- +local_to_utc+:
+
+  - Called when Time.new is invoked with +tz+
+    as the value of positional argument +zone+ or keyword argument +in:+.
+  - Argument: a <tt>Time::tm</tt> object.
+  - Returns: a \Time-like object in the UTC timezone.
+
+- +utc_to_local+:
+
+  - Called when Time.at or Time.now is invoked with +tz+
+    as the value for keyword argument +in:+,
+    and when Time#getlocal or Time#localtime is called with +tz+
+    as the value for positional argument +zone+.
+  - Argument: a <tt>Time::tm</tt> object.
+  - Returns: a \Time-like object in the local timezone.
+
+A custom timezone class may have these instance methods,
+which will be called if defined:
+
+- +abbr+:
+
+  - Called when Time#strftime is invoked with a format involving <tt>%Z</tt>.
+  - Argument: a <tt>Time::tm</tt> object.
+  - Returns: a string abbreviation for the timezone name.
+
+- +dst?+:
+
+  - Called when Time.at or Time.now is invoked with +tz+
+    as the value for keyword argument +in:+,
+    and when Time#getlocal or Time#localtime is called with +tz+
+    as the value for positional argument +zone+.
+  - Argument: a <tt>Time::tm</tt> object.
+  - Returns: whether the time is daylight saving time.
+
+- +name+:
+
+  - Called when <tt>Marshal.dump(t) is invoked
+  - Argument: none.
+  - Returns: the string name of the timezone.
diff --git a/doc/yjit/yjit.md b/doc/yjit/yjit.md
index 3c731247a3..67b2ffa5f0 100644
--- a/doc/yjit/yjit.md
+++ b/doc/yjit/yjit.md
@@ -8,99 +8,135 @@
 YJIT - Yet Another Ruby JIT
 ===========================
 
-**DISCLAIMER: Please note that this project is experimental. It is very much a work in progress, it may cause your software to crash, and current performance results will vary widely, especially on larger applications.**
-
 YJIT is a lightweight, minimalistic Ruby JIT built inside CRuby.
-It lazily compiles code using a Basic Block Versioning (BBV) architecture. The target use case is that of servers running
-Ruby on Rails, an area where MJIT has not yet managed to deliver speedups.
-To simplify development, we currently support only macOS and Linux on x86-64, but an ARM64 backend
-is part of future plans.
+It lazily compiles code using a Basic Block Versioning (BBV) architecture.
+The target use case is that of servers running Ruby on Rails.
+YJIT is currently supported for macOS, Linux and BSD on x86-64 and arm64/aarch64 CPUs.
 This project is open source and falls under the same license as CRuby.
 
+<p align="center"><b>
+    If you're using YJIT in production, please
+    <a href="mailto:maxime.chevalierboisvert@shopify.com">share your success stories with us!</a>
+ </b></p>
+
 If you wish to learn more about the approach taken, here are some conference talks and publications:
+- RubyKaigi 2022 keynote: [Stories from developing YJIT](https://www.youtube.com/watch?v=EMchdR9C8XM)
+- RubyKaigi 2022 talk: [Building a Lightweight IR and Backend for YJIT](https://www.youtube.com/watch?v=BbLGqTxTRp0)
 - RubyKaigi 2021 talk: [YJIT: Building a New JIT Compiler Inside CRuby](https://www.youtube.com/watch?v=PBVLf3yfMs8)
 - Blog post: [YJIT: Building a New JIT Compiler Inside CRuby](https://pointersgonewild.com/2021/06/02/yjit-building-a-new-jit-compiler-inside-cruby/)
+- VMIL 2021 paper: [YJIT: A Basic Block Versioning JIT Compiler for CRuby](https://dl.acm.org/doi/10.1145/3486606.3486781)
 - MoreVMs 2021 talk: [YJIT: Building a New JIT Compiler Inside CRuby](https://www.youtube.com/watch?v=vucLAqv7qpc)
 - ECOOP 2016 talk: [Interprocedural Type Specialization of JavaScript Programs Without Type Analysis](https://www.youtube.com/watch?v=sRNBY7Ss97A)
 - ECOOP 2016 paper: [Interprocedural Type Specialization of JavaScript Programs Without Type Analysis](https://drops.dagstuhl.de/opus/volltexte/2016/6101/pdf/LIPIcs-ECOOP-2016-7.pdf)
 - ECOOP 2015 talk: [Simple and Effective Type Check Removal through Lazy Basic Block Versioning](https://www.youtube.com/watch?v=S-aHBuoiYE0)
 - ECOOP 2015 paper: [Simple and Effective Type Check Removal through Lazy Basic Block Versioning](https://arxiv.org/pdf/1411.0352.pdf)
 
-To cite this repository in your publications, please use this bibtex snippet:
-
-```
-@misc{yjit_ruby_jit,
-  author = {Chevalier-Boisvert, Maxime and Wu, Alan and Patterson, Aaron},
-  title = {YJIT - Yet Another Ruby JIT},
-  year = {2021},
-  publisher = {GitHub},
-  journal = {GitHub repository},
-  howpublished = {\url{https://github.com/Shopify/yjit}},
+To cite YJIT in your publications, please cite the VMIL 2021 paper:
+
+```
+@inproceedings{yjit_vmil2021,
+author = {Chevalier-Boisvert, Maxime and Gibbs, Noah and Boussier, Jean and Wu, Si Xing (Alan) and Patterson, Aaron and Newton, Kevin and Hawthorn, John},
+title = {YJIT: A Basic Block Versioning JIT Compiler for CRuby},
+year = {2021},
+isbn = {9781450391092},
+publisher = {Association for Computing Machinery},
+address = {New York, NY, USA},
+url = {https://doi.org/10.1145/3486606.3486781},
+doi = {10.1145/3486606.3486781},
+booktitle = {Proceedings of the 13th ACM SIGPLAN International Workshop on Virtual Machines and Intermediate Languages},
+pages = {25–32},
+numpages = {8},
+keywords = {ruby, dynamically typed, compiler, optimization, just-in-time, bytecode},
+location = {Chicago, IL, USA},
+series = {VMIL 2021}
 }
 ```
 
 ## Current Limitations
 
-YJIT is a work in progress and as such may not yet be mature enough for mission-critical software. Below is a list of known limitations, all of which we plan to eventually address:
-
-- No garbage collection for generated code.
-- Currently supports only macOS and Linux.
-- Currently supports only x86-64 CPUs.
-
-Because there is no GC for generated code yet, your software could run out of executable memory if it is large enough. You can change how much executable memory is allocated using [YJIT's command-line options](#command-line-options).
+YJIT may not be suitable for certain applications. It currently only supports macOS and Linux on x86-64 and arm64/aarch64 CPUs. YJIT will use more memory than the Ruby interpreter because the JIT compiler needs to generate machine code in memory and maintain additional state information.
+You can change how much executable memory is allocated using [YJIT's command-line options](#command-line-options). There is a slight performance tradeoff because allocating less executable memory could result in the generated machine code being collected more often.
 
 ## Installation
 
-Current YJIT versions are installed by default with CRuby. Make sure to specify the "--yjit" command line option to enable it at runtime.
+### Requirements
 
-Experimental YJIT patches that have not yet been merged with CRuby can be found in ruby-build:
+You will need to install:
+- A C compiler such as GCC or Clang
+- GNU Make and Autoconf
+- The Rust compiler `rustc` and Cargo (if you want to build in dev/debug mode)
+  - The Rust version must be [>= 1.58.0](../../yjit/Cargo.toml).
 
-```
-ruby-build yjit-dev ~/.rubies/ruby-yjit-dev
-```
+To install the Rust build toolchain, we suggest following the [recommended installation method][rust-install]. Rust also provides first class [support][editor-tools] for many source code editors.
 
-They can also be found in the Shopify/yjit repository, which is cloned and build like CRuby.
+[rust-install]: https://www.rust-lang.org/tools/install
+[editor-tools]: https://www.rust-lang.org/tools
 
-Start by cloning the `Shopify/yjit` repository:
+### Building YJIT
 
-```
-git clone https://github.com/Shopify/yjit
+Start by cloning the `ruby/ruby` repository:
+
+```sh
+git clone https://github.com/ruby/ruby yjit
 cd yjit
 ```
 
-The YJIT `ruby` binary can be built with either GCC or Clang. For development, we recommend enabling debug symbols so that assertions are enabled as this makes debugging easier. Enabling debug mode will also make it possible for you to disassemble code generated by YJIT. However, this causes a performance hit. For maximum performance, compile with GCC, without the `-DRUBY_DEBUG` or `-DYJIT_STATS` build options. More detailed build instructions are provided in the [Ruby README](https://github.com/ruby/ruby#how-to-compile-and-install).
-To support disassembly of the generated code, `libcapstone` is also required (`brew install capstone` on MacOS, `sudo apt-get install -y libcapstone-dev` on Ubuntu/Debian and `sudo dnf -y install capstone-devel` on Fedora).
+The YJIT `ruby` binary can be built with either GCC or Clang. It can be built either in dev (debug) mode or in release mode. For maximum performance, compile YJIT in release mode with GCC. More detailed build instructions are provided in the [Ruby README](https://github.com/ruby/ruby#how-to-build).
 
-```
-# Configure with debugging/stats options for development, build and install
+```sh
+# Configure in release mode for maximum performance, build and install
 ./autogen.sh
-./configure cppflags="-DRUBY_DEBUG -DYJIT_STATS" --prefix=$HOME/.rubies/ruby-yjit --disable-install-doc --disable--install-rdoc
-make -j16 install
+./configure --enable-yjit --prefix=$HOME/.rubies/ruby-yjit --disable-install-doc
+make -j && make install
 ```
 
-On macOS, you may need to specify where to find openssl, libyaml and gdbm:
+or
 
+```sh
+# Configure in lower-performance dev (debug) mode for development, build and install
+./autogen.sh
+./configure --enable-yjit=dev --prefix=$HOME/.rubies/ruby-yjit --disable-install-doc
+make -j && make install
 ```
-# Configure with debugging/stats options for development, build and install
-./configure cppflags="-DRUBY_DEBUG -DYJIT_STATS" --prefix=$HOME/.rubies/ruby-yjit --disable-install-doc --disable--install-rdoc --with-opt-dir=$(brew --prefix openssl):$(brew --prefix readline):$(brew --prefix libyaml):$(brew --prefix gdbm)
-make -j16 install
+
+Dev mode includes extended YJIT statistics, but can be slow. For only statistics you can configure in stats mode:
+
+```sh
+# Configure in extended-stats mode without slow runtime checks, build and install
+./autogen.sh
+./configure --enable-yjit=stats --prefix=$HOME/.rubies/ruby-yjit --disable-install-doc
+make -j && make install
 ```
 
-Typically configure will choose default C compiler. To specify the C compiler, use
+On macOS, you may need to specify where to find some libraries:
+
+```sh
+# Install dependencies
+brew install openssl readline libyaml
+
+# Configure in dev (debug) mode for development, build and install
+./autogen.sh
+./configure --enable-yjit=dev --prefix=$HOME/.rubies/ruby-yjit --disable-install-doc --with-opt-dir="$(brew --prefix openssl):$(brew --prefix readline):$(brew --prefix libyaml)"
+make -j && make install
 ```
+
+Typically configure will choose the default C compiler. To specify the C compiler, use
+
+```sh
 # Choosing a specific c compiler
 export CC=/path/to/my/chosen/c/compiler
 ```
+
 before running `./configure`.
 
 You can test that YJIT works correctly by running:
 
-```
+```sh
 # Quick tests found in /bootstraptest
 make btest
 
 # Complete set of tests
-make -j16 test-all
+make -j test-all
 ```
 
 ## Usage
@@ -110,71 +146,111 @@ make -j16 test-all
 Once YJIT is built, you can either use `./miniruby` from within your build directory, or switch to the YJIT version of `ruby`
 by using the `chruby` tool:
 
-```
+```sh
 chruby ruby-yjit
 ruby myscript.rb
 ```
 
 You can dump statistics about compilation and execution by running YJIT with the `--yjit-stats` command-line option:
 
-```
+```sh
 ./miniruby --yjit-stats myscript.rb
 ```
 
 The machine code generated for a given method can be printed by adding `puts RubyVM::YJIT.disasm(method(:method_name))` to a Ruby script. Note that no code will be generated if the method is not compiled.
 
-
 ### Command-Line Options
 
 YJIT supports all command-line options supported by upstream CRuby, but also adds a few YJIT-specific options:
 
-- `--disable-yjit`: turn off YJIT (enabled by default)
-- `--yjit-stats`: produce statistics after the execution of a program (must compile with `cppflags=-DRUBY_DEBUG` to use this)
-- `--yjit-exec-mem-size=N`: size of the executable memory block to allocate, in MiB (default 256 MiB)
-- `--yjit-call-threshold=N`: number of calls after which YJIT begins to compile a function (default 2)
-- `--yjit-max-versions=N`: maximum number of versions to generate per basic block (default 4)
-- `--yjit-greedy-versioning`: greedy versioning mode (disabled by default, may increase code size)
+- `--yjit`: enable YJIT (disabled by default)
+- `--yjit-call-threshold=N`: number of calls after which YJIT begins to compile a function (default 30)
+- `--yjit-exec-mem-size=N`: size of the executable memory block to allocate, in MiB (default 64 MiB)
+- `--yjit-stats`: print statistics after the execution of a program (incurs a run-time cost)
+- `--yjit-trace-exits`: produce a Marshal dump of backtraces from specific exits. Automatically enables `--yjit-stats`
+
+Note that there is also an environment variable `RUBY_YJIT_ENABLE` which can be used to enable YJIT.
+This can be useful for some deployment scripts where specifying an extra command-line option to Ruby is not practical.
 
 ### Benchmarking
 
 We have collected a set of benchmarks and implemented a simple benchmarking harness in the [yjit-bench](https://github.com/Shopify/yjit-bench) repository. This benchmarking harness is designed to disable CPU frequency scaling, set process affinity and disable address space randomization so that the variance between benchmarking runs will be as small as possible. Please kindly note that we are at an early stage in this project.
 
-### Performance Tips
+## Performance Tips for Production Deployments
+
+While YJIT options default to what we think would work well for most workloads,
+they might not necessarily be the best configuration for your application.
+
+This section covers tips on improving YJIT performance in case YJIT does not
+speed up your application in production.
+
+### Increasing --yjit-exec-mem-size
+
+When JIT code size (`RubyVM::YJIT.runtime_stats[:code_region_size]`) reaches this value,
+YJIT triggers "code GC" that frees all JIT code and starts recompiling everything.
+Compiling code takes some time, so scheduling code GC too frequently slows down your application.
+Increasing `--yjit-exec-mem-size` may speed up your application if `RubyVM::YJIT.runtime_stats[:code_gc_count]` is not 0 or 1.
+
+### Running workers as long as possible
+
+It's helpful to call the same code as many times as possible before a process restarts.
+If a process is killed too frequently, the time taken for compiling methods may outweigh
+the speedup obtained by compiling them.
+
+You should monitor the number of requests each process has served.
+If you're periodically killing worker processes, e.g. with `unicorn-worker-killer` or `puma_worker_killer`,
+you may want to reduce the killing frequency or increase the limit.
+
+## Saving YJIT Memory Usage
+
+YJIT allocates memory for JIT code and metadata. Enabling YJIT generally results in more memory usage.
+
+This section goes over tips on minimizing YJIT memory usage in case it uses more than your capacity.
+
+### Increasing --yjit-call-threshold
+
+As of Ruby 3.2, `--yjit-call-threshold` defaults to 30. With this default, some applications end up
+compiling methods that are used only during the application boot. Increasing this option may help
+you reduce the size of JIT code and metadata. It's worth trying different values like `--yjit-call-threshold=100`.
+
+Note that increasing the value too much may result in compiling code too late.
+You should monitor how many requests each worker processes before it's restarted. For example,
+if each process only handles 1000 requests, `--yjit-call-threshold=1000` might be too large for your application.
+
+### Decreasing --yjit-exec-mem-size
+
+`--yjit-exec-mem-size` specifies the JIT code size, but YJIT also uses memory for its metadata,
+which often consumes more memory than JIT code. Generally, YJIT adds memory overhead by roughly
+3-4x of `--yjit-exec-mem-size` in production as of Ruby 3.2. You should multiply that by the number
+of worker processes to estimate the worst case memory overhead.
+
+Running code GC adds overhead, but it could be still faster than recovering from a whole process killed by OOM.
 
-This section contains tips on writing Ruby code that will run as fast as possible on YJIT. Some of this advice is based on current limitations of YJIT, while other advice is broadly applicable. It probably won't be practical to apply these tips everywhere in your codebase, but you can profile your code using a tool such as [stackprof](https://github.com/tmm1/stackprof) and refactor the specific methods that make up the largest fractions of the execution time.
+## Code Optimization Tips
 
-- Use exceptions for error recovery only, not as part of normal control-flow
+This section contains tips on writing Ruby code that will run as fast as possible on YJIT. Some of this advice is based on current limitations of YJIT, while other advice is broadly applicable. It probably won't be practical to apply these tips everywhere in your codebase. You should ideally start by profiling your application using a tool such as [stackprof](https://github.com/tmm1/stackprof) so that you can determine which methods make up most of the execution time. You can then refactor the specific methods that make up the largest fractions of the execution time. We do not recommend modifying your entire codebase based on the current limitations of YJIT.
+
+- Avoid using `OpenStruct`
 - Avoid redefining basic integer operations (i.e. +, -, <, >, etc.)
 - Avoid redefining the meaning of `nil`, equality, etc.
 - Avoid allocating objects in the hot parts of your code
-- Use while loops if you can, instead of `integer.times`
 - Minimize layers of indirection
   - Avoid classes that wrap objects if you can
   - Avoid methods that just call another method, trivial one liner methods
-- CRuby method calls are costly. Favor larger methods over smaller methods.
 - Try to write code so that the same variables always have the same type
+- Use `while` loops if you can, instead of C methods like `Array#each`
+  - This is not idiomatic Ruby, but could help in hot methods
+- CRuby method calls are costly. Avoid things such as methods that only return a value from a hash or return a constant.
 
-You can also compile YJIT in debug mode and use the `--yjit-stats` command-line option to see which bytecodes cause YJIT to exit, and refactor your code to avoid using these instructions in the hottest methods of your code.
-
-### Memory Statistics
-
-YJIT, including in production configuration, keeps track of the size of generated code. If you check YJIT.runtime_stats you can see them:
-
-```
-$ RUBYOPT="--yjit" irb
-irb(main):001:0> RubyVM::YJIT.runtime_stats
-=> {:inline_code_size=>331945, :outlined_code_size=>272980}
-```
-
-These are the size in bytes of generated inlined code and generated outlined code. If the combined sizes for generated code are very close to the total YJIT exec-mem-size (see above), YJIT will stop generating code once the limit is reached. Try to make sure you have enough exec-mem-size for the program you're running. By default YJIT will allocate 268,435,456 bytes (256 MiB) of space for generated inlined and outlined code.
+You can also use the `--yjit-stats` command-line option to see which bytecodes cause YJIT to exit, and refactor your code to avoid using these instructions in the hottest methods of your code.
 
 ### Other Statistics
 
-If you compile Ruby with RUBY_DEBUG and/or YJIT_STATS defined and run with "--yjit --yjit-stats", YJIT will track and return performance statistics in RubyVM::YJIT.runtime_stats.
+If you run `ruby` with `--yjit --yjit-stats`, YJIT will track and return performance statistics in `RubyVM::YJIT.runtime_stats`.
 
-```
+```rb
 $ RUBYOPT="--yjit --yjit-stats" irb
-irb(main):001:0> YJIT.runtime_stats
+irb(main):001:0> RubyVM::YJIT.runtime_stats
 =>
 {:inline_code_size=>340745,
  :outlined_code_size=>297664,
@@ -188,16 +264,24 @@ irb(main):001:0> YJIT.runtime_stats
 
 Some of the counters include:
 
-:exec_instruction - how many Ruby bytecode instructions have been executed
-:binding_allocations - number of bindings allocated
-:binding_set - number of variables set via a binding
-:vm_insns_count - number of instructions executed by the Ruby interpreter
-:compiled_iseq_count - number of bytecode sequences compiled
+* :exec_instruction - how many Ruby bytecode instructions have been executed
+* :binding_allocations - number of bindings allocated
+* :binding_set - number of variables set via a binding
+* :code_gc_count - number of garbage collections of compiled code since process start
+* :vm_insns_count - number of instructions executed by the Ruby interpreter
+* :compiled_iseq_count - number of bytecode sequences compiled
+* :inline_code_size - size in bytes of compiled YJIT blocks
+* :outline_code_size - size in bytes of YJIT error-handling compiled code
+* :side_exit_count - number of side exits taken at runtime
+* :total_exit_count - number of exits, including side exits, taken at runtime
+* :avg_len_in_yjit - avg. number of instructions in compiled blocks before exiting to interpreter
 
 Counters starting with "exit_" show reasons for YJIT code taking a side exit (return to the interpreter.) See yjit_hacking.md for more details.
 
 Performance counter names are not guaranteed to remain the same between Ruby versions. If you're curious what one does, it's usually best to search the source code for it &mdash; but it may change in a later Ruby version.
 
+The printed text after a --yjit-stats run includes other information that may be named differently than the information in runtime_stats.
+
 ## Contributing
 
 We welcome open source contributors. You should feel free to open new issues to report bugs or just to ask questions.
@@ -215,20 +299,36 @@ you can contribute things we will want to merge into YJIT.
 ### Source Code Organization
 
 The YJIT source code is divided between:
-- `yjit_asm.c`: x86 in-memory assembler we use to generate machine code
-- `yjit_codegen.c`: logic for translating Ruby bytecode to machine code
-- `yjit_core.c`: basic block versioning logic, core structure of YJIT
-- `yjit_iface.c`: code YJIT uses to interface with the rest of CRuby
+- `yjit.c`: code YJIT uses to interface with the rest of CRuby
 - `yjit.h`: C definitions YJIT exposes to the rest of the CRuby
 - `yjit.rb`: `YJIT` Ruby module that is exposed to Ruby
-- `misc/test_yjit_asm.sh`: script to compile and run the in-memory assembler tests
-- `misc/yjit_asm_tests.c`: tests for the in-memory assembler
+- `yjit/src/asm/*`: in-memory assembler we use to generate machine code
+- `yjit/src/codegen.rs`: logic for translating Ruby bytecode to machine code
+- `yjit/src/core.rb`: basic block versioning logic, core structure of YJIT
+- `yjit/src/stats.rs`: gathering of run-time statistics
+- `yjit/src/options.rs`: handling of command-line options
+- `yjit/bindgen/src/main.rs`: C bindings exposed to the Rust codebase through bindgen
+- `yjit/src/cruby.rs`: C bindings manually exposed to the Rust codebase
 
 The core of CRuby's interpreter logic is found in:
 - `insns.def`: defines Ruby's bytecode instructions (gets compiled into `vm.inc`)
 - `vm_insnshelper.c`: logic used by Ruby's bytecode instructions
 - `vm_exec.c`: Ruby interpreter loop
 
+### Generating C bindings with bindgen
+
+In order to expose C functions to the Rust codebase, you will need to generate C bindings:
+
+```sh
+CC=clang ./configure --enable-yjit=dev
+make -j yjit-bindgen
+```
+
+This uses the bindgen tools to generate/update `yjit/src/cruby_bindings.inc.rs` based on the
+bindings listed in `yjit/bindgen/src/main.rs`. Avoid manually editing this file
+as it could be automatically regenerated at a later time. If you need to manually add C bindings,
+add them to `yjit/cruby.rs` instead.
+
 ### Coding & Debugging Protips
 
 There are 3 test suites:
@@ -239,37 +339,79 @@ There are 3 test suites:
 
 The tests can be run in parallel like this:
 
-```
-make -j16 test-all RUN_OPTS="--yjit-call-threshold=1"
+```sh
+make -j test-all RUN_OPTS="--yjit-call-threshold=1"
 ```
 
 Or single-threaded like this, to more easily identify which specific test is failing:
 
-```
+```sh
 make test-all TESTOPTS=--verbose RUN_OPTS="--yjit-call-threshold=1"
 ```
 
 To debug a single test in `test-all`:
 
-```
+```sh
 make test-all TESTS='test/-ext-/marshal/test_usrmarshal.rb' RUNRUBYOPT=--debugger=lldb RUN_OPTS="--yjit-call-threshold=1"
 ```
 
 You can also run one specific test in `btest`:
 
-```
+```sh
 make btest BTESTS=bootstraptest/test_ractor.rb RUN_OPTS="--yjit-call-threshold=1"
 ```
 
 There are shortcuts to run/debug your own test/repro in `test.rb`:
 
-```
+```sh
 make run  # runs ./miniruby test.rb
 make lldb # launches ./miniruby test.rb in lldb
 ```
 
 You can use the Intel syntax for disassembly in LLDB, keeping it consistent with YJIT's disassembly:
 
-```
+```sh
 echo "settings set target.x86-disassembly-flavor intel" >> ~/.lldbinit
 ```
+
+## Running x86 YJIT on Apple's Rosetta
+
+For development purposes, it is possible to run x86 YJIT on an Apple M1 via Rosetta.  You can find basic
+instructions below, but there are a few caveats listed further down.
+
+First, install Rosetta:
+
+```sh
+$ softwareupdate --install-rosetta
+```
+
+Now any command can be run with Rosetta via the `arch` command line tool.
+
+Then you can start your shell in an x86 environment:
+
+```sh
+$ arch -x86_64 zsh
+```
+
+You can double check your current architecture via the `arch` command:
+
+```sh
+$ arch -x86_64 zsh
+$ arch
+i386
+```
+
+You may need to set the default target for `rustc` to x86-64, e.g.
+
+```sh
+$ rustup default stable-x86_64-apple-darwin
+```
+
+While in your i386 shell, install Cargo and Homebrew, then hack away!
+
+### Rosetta Caveats
+
+1. You must install a version of Homebrew for each architecture
+2. Cargo will install in $HOME/.cargo by default, and I don't know a good way to change architectures after install
+
+If you use Fish shell you can [read this link](https://tenderlovemaking.com/2022/01/07/homebrew-rosetta-and-ruby.html) for information on making the dev environment easier.
diff --git a/enc/Makefile.in b/enc/Makefile.in
index 5e5d39cd76..9d0c367134 100644
--- a/enc/Makefile.in
+++ b/enc/Makefile.in
@@ -22,6 +22,7 @@ TRANSSODIR = $(ENCSODIR)/trans
 DLEXT = @DLEXT@
 OBJEXT = @OBJEXT@
 LIBEXT = @LIBEXT@
+EXEEXT = @EXEEXT@
 TIMESTAMPDIR  = $(EXTOUT)/.timestamp
 ENC_TRANS_D   = $(TIMESTAMPDIR)/.enc-trans.time
 ENC_TRANS_SO_D = $(TIMESTAMPDIR)/.enc-trans.so.time
@@ -35,6 +36,7 @@ RUBY_SO_NAME = @RUBY_SO_NAME@
 LIBRUBY = @LIBRUBY@
 LIBRUBYARG_SHARED = @LIBRUBYARG_SHARED@
 LIBRUBYARG_STATIC = $(LIBRUBYARG_SHARED)
+BUILTRUBY = $(topdir)/miniruby$(EXEEXT)
 
 empty =
 AR = @AR@
@@ -49,7 +51,7 @@ optflags = @optflags@
 debugflags = @debugflags@
 warnflags = @warnflags@
 CCDLFLAGS = @CCDLFLAGS@
-INCFLAGS = -I. -I$(arch_hdrdir) -I$(hdrdir) -I$(top_srcdir)
+INCFLAGS = -I. -I$(arch_hdrdir) -I$(hdrdir) -I$(top_srcdir) @incflags@
 DEFS = @DEFS@
 CPPFLAGS = @CPPFLAGS@ -DONIG_ENC_REGISTER=rb_enc_register
 LDFLAGS = @LDFLAGS@
diff --git a/enc/ascii.c b/enc/ascii.c
index a2fef2f879..ae7db97f25 100644
--- a/enc/ascii.c
+++ b/enc/ascii.c
@@ -33,8 +33,8 @@
 # include "encindex.h"
 #endif
 
-#ifndef ENCINDEX_ASCII
-# define ENCINDEX_ASCII 0
+#ifndef ENCINDEX_ASCII_8BIT
+# define ENCINDEX_ASCII_8BIT 0
 #endif
 
 OnigEncodingDefine(ascii, ASCII) = {
@@ -55,7 +55,7 @@ OnigEncodingDefine(ascii, ASCII) = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   onigenc_single_byte_ascii_only_case_map,
-  ENCINDEX_ASCII,
+  ENCINDEX_ASCII_8BIT,
   ONIGENC_FLAG_NONE,
 };
 ENC_ALIAS("BINARY", "ASCII-8BIT")
diff --git a/enc/cesu_8.c b/enc/cesu_8.c
index decbb928f4..75f62df280 100644
--- a/enc/cesu_8.c
+++ b/enc/cesu_8.c
@@ -42,6 +42,8 @@
 #define VALID_CODE_LIMIT  0x0010ffff
 
 #define utf8_islead(c)     ((UChar )((c) & 0xc0) != 0x80)
+#define utf16_is_high_surrogate(v) ((v >> 10) == 0x36)
+#define utf16_is_low_surrogate(v)  ((v >> 10) == 0x37)
 
 static const int EncLen_CESU8[] = {
   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
@@ -283,6 +285,12 @@ is_mbc_newline(const UChar* p, const UChar* end, OnigEncoding enc)
   return 0;
 }
 
+static int
+utf8_decode_3byte_sequence(const UChar* p)
+{
+    return ((p[0] & 0xF) << 12) | ((p[1] & 0x3f) << 6) | (p[2] & 0x3f);
+}
+
 static OnigCodePoint
 mbc_to_code(const UChar* p, const UChar* end, OnigEncoding enc)
 {
@@ -295,11 +303,11 @@ mbc_to_code(const UChar* p, const UChar* end, OnigEncoding enc)
     case 2:
       return ((p[0] & 0x1F)  << 6) | (p[1] & 0x3f);
     case 3:
-      return ((p[0] & 0xF) << 12) | ((p[1] & 0x3f) << 6) | (p[2] & 0x3f);
+      return utf8_decode_3byte_sequence(p);
     case 6:
       {
-          int high = ((p[0] & 0xF) << 12) | ((p[1] & 0x3f) << 6) | (p[2] & 0x3f);
-          int low  = ((p[3] & 0xF) << 12) | ((p[4] & 0x3f) << 6) | (p[5] & 0x3f);
+          int high = utf8_decode_3byte_sequence(p);
+          int low  = utf8_decode_3byte_sequence(p + 3);
           return ((high & 0x03ff) << 10) + (low & 0x03ff) + 0x10000;
       }
   }
@@ -410,7 +418,6 @@ get_ctype_code_range(OnigCtype ctype, OnigCodePoint *sb_out,
   return onigenc_unicode_ctype_code_range(ctype, ranges);
 }
 
-
 static UChar*
 left_adjust_char_head(const UChar* start, const UChar* s, const UChar* end, OnigEncoding enc ARG_UNUSED)
 {
@@ -420,6 +427,14 @@ left_adjust_char_head(const UChar* start, const UChar* s, const UChar* end, Onig
   p = s;
 
   while (!utf8_islead(*p) && p > start) p--;
+
+  if (p > start && s - p == 2 && utf16_is_low_surrogate(utf8_decode_3byte_sequence(p))) {
+    const UChar *p_surrogate_pair = p - 1;
+    while (!utf8_islead(*p_surrogate_pair) && p_surrogate_pair > start) p_surrogate_pair--;
+    if (p - p_surrogate_pair == 3 && utf16_is_high_surrogate(utf8_decode_3byte_sequence(p_surrogate_pair))) {
+      return (UChar* )p_surrogate_pair;
+    }
+  }
   return (UChar* )p;
 }
 
diff --git a/enc/depend b/enc/depend
index 60c5a3ebb2..973ad93010 100644
--- a/enc/depend
+++ b/enc/depend
@@ -7018,6 +7018,7 @@ enc/trans/iso2022.$(OBJEXT): internal/attr/nodiscard.h
 enc/trans/iso2022.$(OBJEXT): internal/attr/noexcept.h
 enc/trans/iso2022.$(OBJEXT): internal/attr/noinline.h
 enc/trans/iso2022.$(OBJEXT): internal/attr/nonnull.h
+enc/trans/iso2022.$(OBJEXT): internal/attr/nonstring.h
 enc/trans/iso2022.$(OBJEXT): internal/attr/noreturn.h
 enc/trans/iso2022.$(OBJEXT): internal/attr/pure.h
 enc/trans/iso2022.$(OBJEXT): internal/attr/restrict.h
diff --git a/enc/encdb.c b/enc/encdb.c
index a1936df804..8247e9ff6a 100644
--- a/enc/encdb.c
+++ b/enc/encdb.c
@@ -17,7 +17,7 @@
 #define ENC_DEFINE(name) rb_encdb_declare(name)
 #define ENC_SET_BASE(name, orig) rb_enc_set_base((name), (orig))
 #define ENC_SET_DUMMY(name, orig) rb_enc_set_dummy(name)
-#define ENC_DUMMY_UNICODE(name) rb_encdb_set_unicode(rb_enc_set_dummy(ENC_REPLICATE((name), name "BE")))
+#define ENC_DUMMY_UNICODE(name) ENC_DUMMY(name)
 
 void
 Init_encdb(void)
diff --git a/enc/jis/props.h.blt b/enc/jis/props.h.blt
index 54aa94f8bc..508a084449 100644
--- a/enc/jis/props.h.blt
+++ b/enc/jis/props.h.blt
@@ -69,7 +69,7 @@ struct enc_property {
     unsigned char ctype;
 };
 
-static const struct enc_property *onig_jis_property(/*const char *str, unsigned int len*/);
+static const struct enc_property *onig_jis_property(register const char *str, register size_t len);
 #line 43 "enc/jis/props.kwd"
 struct enc_property;
 
@@ -82,7 +82,7 @@ struct enc_property;
 
 #ifndef GPERF_DOWNCASE
 #define GPERF_DOWNCASE 1
-static unsigned char gperf_downcase[256] =
+static const unsigned char gperf_downcase[256] =
   {
       0,   1,   2,   3,   4,   5,   6,   7,   8,   9,  10,  11,  12,  13,  14,
      15,  16,  17,  18,  19,  20,  21,  22,  23,  24,  25,  26,  27,  28,  29,
diff --git a/enc/jis/props.kwd b/enc/jis/props.kwd
index 659cf0aff4..9606828459 100644
--- a/enc/jis/props.kwd
+++ b/enc/jis/props.kwd
@@ -37,7 +37,7 @@ struct enc_property {
     unsigned char ctype;
 };
 
-static const struct enc_property *onig_jis_property(/*!ANSI{*/const char *str, unsigned int len/*}!ANSI*/);
+static const struct enc_property *onig_jis_property(register const char *str, register size_t len);
 %}
 
 struct enc_property;
diff --git a/enc/jis/props.src b/enc/jis/props.src
index 659cf0aff4..9606828459 100644
--- a/enc/jis/props.src
+++ b/enc/jis/props.src
@@ -37,7 +37,7 @@ struct enc_property {
     unsigned char ctype;
 };
 
-static const struct enc_property *onig_jis_property(/*!ANSI{*/const char *str, unsigned int len/*}!ANSI*/);
+static const struct enc_property *onig_jis_property(register const char *str, register size_t len);
 %}
 
 struct enc_property;
diff --git a/enc/make_encmake.rb b/enc/make_encmake.rb
index bc0597e3f4..fcfc2c9267 100755
--- a/enc/make_encmake.rb
+++ b/enc/make_encmake.rb
@@ -134,7 +134,7 @@ else
 end
 mkin = File.read(File.join($srcdir, "Makefile.in"))
 mkin.gsub!(/@(#{CONFIG.keys.join('|')})@/) {CONFIG[$1]}
-open(ARGV[0], 'wb') {|f|
+File.open(ARGV[0], 'wb') {|f|
   f.puts mkin, dep
 }
 if MODULE_TYPE == :static
diff --git a/enc/trans/newline.trans b/enc/trans/newline.trans
index 9e763407f9..95e082f5bd 100644
--- a/enc/trans/newline.trans
+++ b/enc/trans/newline.trans
@@ -17,10 +17,16 @@
   map_cr["0a"] = "0d"
 
   transcode_generate_node(ActionMap.parse(map_cr), "cr_newline")
+
+  map_normalize = {}
+  map_normalize["{00-ff}"] = :func_so
+
+  transcode_generate_node(ActionMap.parse(map_normalize), "lf_newline")
 %>
 
 <%= transcode_generated_code %>
 
+#define lf_newline universal_newline
 #define STATE (sp[0])
 #define NORMAL 0
 #define JUST_AFTER_CR 1
@@ -126,10 +132,24 @@ rb_cr_newline = {
     0, 0, 0, 0
 };
 
+static const rb_transcoder
+rb_lf_newline = {
+    "", "lf_newline", lf_newline,
+    TRANSCODE_TABLE_INFO,
+    1, /* input_unit_length */
+    1, /* max_input */
+    2, /* max_output */
+    asciicompat_converter, /* asciicompat_type */
+    2, universal_newline_init, universal_newline_init, /* state_size, state_init, state_fini */
+    0, 0, 0, fun_so_universal_newline,
+    universal_newline_finish
+};
+
 void
 Init_newline(void)
 {
     rb_register_transcoder(&rb_universal_newline);
     rb_register_transcoder(&rb_crlf_newline);
     rb_register_transcoder(&rb_cr_newline);
+    rb_register_transcoder(&rb_lf_newline);
 }
diff --git a/enc/unicode/14.0.0/casefold.h b/enc/unicode/15.0.0/casefold.h
index d387cff628..51120d867d 100644
--- a/enc/unicode/14.0.0/casefold.h
+++ b/enc/unicode/15.0.0/casefold.h
@@ -1,15 +1,15 @@
 /* DO NOT EDIT THIS FILE. */
-/* Generated by enc/unicode/case-folding.rb */
+/* Generated by enc-case-folding.rb */
 
 #if defined ONIG_UNICODE_VERSION_STRING && !( \
-      ONIG_UNICODE_VERSION_MAJOR == 14 && \
+      ONIG_UNICODE_VERSION_MAJOR == 15 && \
       ONIG_UNICODE_VERSION_MINOR == 0 && \
       ONIG_UNICODE_VERSION_TEENY == 0 && \
       1)
 # error ONIG_UNICODE_VERSION_STRING mismatch
 #endif
-#define ONIG_UNICODE_VERSION_STRING "14.0.0"
-#define ONIG_UNICODE_VERSION_MAJOR 14
+#define ONIG_UNICODE_VERSION_STRING "15.0.0"
+#define ONIG_UNICODE_VERSION_MAJOR 15
 #define ONIG_UNICODE_VERSION_MINOR 0
 #define ONIG_UNICODE_VERSION_TEENY 0
 
diff --git a/enc/unicode/14.0.0/name2ctype.h b/enc/unicode/15.0.0/name2ctype.h
index 99a3eeca19..a2c996423d 100644
--- a/enc/unicode/14.0.0/name2ctype.h
+++ b/enc/unicode/15.0.0/name2ctype.h
@@ -43,7 +43,7 @@ static const OnigCodePoint CR_NEWLINE[] = {
 
 /* 'Alpha': [[:Alpha:]] */
 static const OnigCodePoint CR_Alpha[] = {
-	722,
+	732,
 	0x0041, 0x005a,
 	0x0061, 0x007a,
 	0x00aa, 0x00aa,
@@ -178,8 +178,7 @@ static const OnigCodePoint CR_Alpha[] = {
 	0x0bca, 0x0bcc,
 	0x0bd0, 0x0bd0,
 	0x0bd7, 0x0bd7,
-	0x0c00, 0x0c03,
-	0x0c05, 0x0c0c,
+	0x0c00, 0x0c0c,
 	0x0c0e, 0x0c10,
 	0x0c12, 0x0c28,
 	0x0c2a, 0x0c39,
@@ -202,7 +201,7 @@ static const OnigCodePoint CR_Alpha[] = {
 	0x0cd5, 0x0cd6,
 	0x0cdd, 0x0cde,
 	0x0ce0, 0x0ce3,
-	0x0cf1, 0x0cf2,
+	0x0cf1, 0x0cf3,
 	0x0d00, 0x0d0c,
 	0x0d0e, 0x0d10,
 	0x0d12, 0x0d3a,
@@ -240,7 +239,7 @@ static const OnigCodePoint CR_Alpha[] = {
 	0x0f00, 0x0f00,
 	0x0f40, 0x0f47,
 	0x0f49, 0x0f6c,
-	0x0f71, 0x0f81,
+	0x0f71, 0x0f83,
 	0x0f88, 0x0f97,
 	0x0f99, 0x0fbc,
 	0x1000, 0x1036,
@@ -542,7 +541,7 @@ static const OnigCodePoint CR_Alpha[] = {
 	0x10fe0, 0x10ff6,
 	0x11000, 0x11045,
 	0x11071, 0x11075,
-	0x11082, 0x110b8,
+	0x11080, 0x110b8,
 	0x110c2, 0x110c2,
 	0x110d0, 0x110e8,
 	0x11100, 0x11132,
@@ -557,7 +556,7 @@ static const OnigCodePoint CR_Alpha[] = {
 	0x11200, 0x11211,
 	0x11213, 0x11234,
 	0x11237, 0x11237,
-	0x1123e, 0x1123e,
+	0x1123e, 0x11241,
 	0x11280, 0x11286,
 	0x11288, 0x11288,
 	0x1128a, 0x1128d,
@@ -637,12 +636,16 @@ static const OnigCodePoint CR_Alpha[] = {
 	0x11d93, 0x11d96,
 	0x11d98, 0x11d98,
 	0x11ee0, 0x11ef6,
+	0x11f00, 0x11f10,
+	0x11f12, 0x11f3a,
+	0x11f3e, 0x11f40,
 	0x11fb0, 0x11fb0,
 	0x12000, 0x12399,
 	0x12400, 0x1246e,
 	0x12480, 0x12543,
 	0x12f90, 0x12ff0,
-	0x13000, 0x1342e,
+	0x13000, 0x1342f,
+	0x13441, 0x13446,
 	0x14400, 0x14646,
 	0x16800, 0x16a38,
 	0x16a40, 0x16a5e,
@@ -666,7 +669,9 @@ static const OnigCodePoint CR_Alpha[] = {
 	0x1aff5, 0x1affb,
 	0x1affd, 0x1affe,
 	0x1b000, 0x1b122,
+	0x1b132, 0x1b132,
 	0x1b150, 0x1b152,
+	0x1b155, 0x1b155,
 	0x1b164, 0x1b167,
 	0x1b170, 0x1b2fb,
 	0x1bc00, 0x1bc6a,
@@ -705,16 +710,20 @@ static const OnigCodePoint CR_Alpha[] = {
 	0x1d7aa, 0x1d7c2,
 	0x1d7c4, 0x1d7cb,
 	0x1df00, 0x1df1e,
+	0x1df25, 0x1df2a,
 	0x1e000, 0x1e006,
 	0x1e008, 0x1e018,
 	0x1e01b, 0x1e021,
 	0x1e023, 0x1e024,
 	0x1e026, 0x1e02a,
+	0x1e030, 0x1e06d,
+	0x1e08f, 0x1e08f,
 	0x1e100, 0x1e12c,
 	0x1e137, 0x1e13d,
 	0x1e14e, 0x1e14e,
 	0x1e290, 0x1e2ad,
 	0x1e2c0, 0x1e2eb,
+	0x1e4d0, 0x1e4eb,
 	0x1e7e0, 0x1e7e6,
 	0x1e7e8, 0x1e7eb,
 	0x1e7ed, 0x1e7ee,
@@ -760,12 +769,13 @@ static const OnigCodePoint CR_Alpha[] = {
 	0x1f150, 0x1f169,
 	0x1f170, 0x1f189,
 	0x20000, 0x2a6df,
-	0x2a700, 0x2b738,
+	0x2a700, 0x2b739,
 	0x2b740, 0x2b81d,
 	0x2b820, 0x2cea1,
 	0x2ceb0, 0x2ebe0,
 	0x2f800, 0x2fa1d,
 	0x30000, 0x3134a,
+	0x31350, 0x323af,
 }; /* CR_Alpha */
 
 /* 'Blank': [[:Blank:]] */
@@ -790,7 +800,7 @@ static const OnigCodePoint CR_Cntrl[] = {
 
 /* 'Digit': [[:Digit:]] */
 static const OnigCodePoint CR_Digit[] = {
-	62,
+	64,
 	0x0030, 0x0039,
 	0x0660, 0x0669,
 	0x06f0, 0x06f9,
@@ -845,19 +855,21 @@ static const OnigCodePoint CR_Digit[] = {
 	0x11c50, 0x11c59,
 	0x11d50, 0x11d59,
 	0x11da0, 0x11da9,
+	0x11f50, 0x11f59,
 	0x16a60, 0x16a69,
 	0x16ac0, 0x16ac9,
 	0x16b50, 0x16b59,
 	0x1d7ce, 0x1d7ff,
 	0x1e140, 0x1e149,
 	0x1e2f0, 0x1e2f9,
+	0x1e4f0, 0x1e4f9,
 	0x1e950, 0x1e959,
 	0x1fbf0, 0x1fbf9,
 }; /* CR_Digit */
 
 /* 'Graph': [[:Graph:]] */
 static const OnigCodePoint CR_Graph[] = {
-	703,
+	712,
 	0x0021, 0x007e,
 	0x00a1, 0x0377,
 	0x037a, 0x037f,
@@ -980,7 +992,7 @@ static const OnigCodePoint CR_Graph[] = {
 	0x0cdd, 0x0cde,
 	0x0ce0, 0x0ce3,
 	0x0ce6, 0x0cef,
-	0x0cf1, 0x0cf2,
+	0x0cf1, 0x0cf3,
 	0x0d00, 0x0d0c,
 	0x0d0e, 0x0d10,
 	0x0d12, 0x0d44,
@@ -1010,7 +1022,7 @@ static const OnigCodePoint CR_Graph[] = {
 	0x0ea7, 0x0ebd,
 	0x0ec0, 0x0ec4,
 	0x0ec6, 0x0ec6,
-	0x0ec8, 0x0ecd,
+	0x0ec8, 0x0ece,
 	0x0ed0, 0x0ed9,
 	0x0edc, 0x0edf,
 	0x0f00, 0x0f47,
@@ -1285,7 +1297,7 @@ static const OnigCodePoint CR_Graph[] = {
 	0x10e80, 0x10ea9,
 	0x10eab, 0x10ead,
 	0x10eb0, 0x10eb1,
-	0x10f00, 0x10f27,
+	0x10efd, 0x10f27,
 	0x10f30, 0x10f59,
 	0x10f70, 0x10f89,
 	0x10fb0, 0x10fcb,
@@ -1302,7 +1314,7 @@ static const OnigCodePoint CR_Graph[] = {
 	0x11180, 0x111df,
 	0x111e1, 0x111f4,
 	0x11200, 0x11211,
-	0x11213, 0x1123e,
+	0x11213, 0x11241,
 	0x11280, 0x11286,
 	0x11288, 0x11288,
 	0x1128a, 0x1128d,
@@ -1355,6 +1367,7 @@ static const OnigCodePoint CR_Graph[] = {
 	0x11a00, 0x11a47,
 	0x11a50, 0x11aa2,
 	0x11ab0, 0x11af8,
+	0x11b00, 0x11b09,
 	0x11c00, 0x11c08,
 	0x11c0a, 0x11c36,
 	0x11c38, 0x11c45,
@@ -1376,6 +1389,9 @@ static const OnigCodePoint CR_Graph[] = {
 	0x11d93, 0x11d98,
 	0x11da0, 0x11da9,
 	0x11ee0, 0x11ef8,
+	0x11f00, 0x11f10,
+	0x11f12, 0x11f3a,
+	0x11f3e, 0x11f59,
 	0x11fb0, 0x11fb0,
 	0x11fc0, 0x11ff1,
 	0x11fff, 0x12399,
@@ -1383,8 +1399,7 @@ static const OnigCodePoint CR_Graph[] = {
 	0x12470, 0x12474,
 	0x12480, 0x12543,
 	0x12f90, 0x12ff2,
-	0x13000, 0x1342e,
-	0x13430, 0x13438,
+	0x13000, 0x13455,
 	0x14400, 0x14646,
 	0x16800, 0x16a38,
 	0x16a40, 0x16a5e,
@@ -1411,7 +1426,9 @@ static const OnigCodePoint CR_Graph[] = {
 	0x1aff5, 0x1affb,
 	0x1affd, 0x1affe,
 	0x1b000, 0x1b122,
+	0x1b132, 0x1b132,
 	0x1b150, 0x1b152,
+	0x1b155, 0x1b155,
 	0x1b164, 0x1b167,
 	0x1b170, 0x1b2fb,
 	0x1bc00, 0x1bc6a,
@@ -1426,6 +1443,7 @@ static const OnigCodePoint CR_Graph[] = {
 	0x1d100, 0x1d126,
 	0x1d129, 0x1d1ea,
 	0x1d200, 0x1d245,
+	0x1d2c0, 0x1d2d3,
 	0x1d2e0, 0x1d2f3,
 	0x1d300, 0x1d356,
 	0x1d360, 0x1d378,
@@ -1453,11 +1471,14 @@ static const OnigCodePoint CR_Graph[] = {
 	0x1da9b, 0x1da9f,
 	0x1daa1, 0x1daaf,
 	0x1df00, 0x1df1e,
+	0x1df25, 0x1df2a,
 	0x1e000, 0x1e006,
 	0x1e008, 0x1e018,
 	0x1e01b, 0x1e021,
 	0x1e023, 0x1e024,
 	0x1e026, 0x1e02a,
+	0x1e030, 0x1e06d,
+	0x1e08f, 0x1e08f,
 	0x1e100, 0x1e12c,
 	0x1e130, 0x1e13d,
 	0x1e140, 0x1e149,
@@ -1465,6 +1486,7 @@ static const OnigCodePoint CR_Graph[] = {
 	0x1e290, 0x1e2ae,
 	0x1e2c0, 0x1e2f9,
 	0x1e2ff, 0x1e2ff,
+	0x1e4d0, 0x1e4f9,
 	0x1e7e0, 0x1e7e6,
 	0x1e7e8, 0x1e7eb,
 	0x1e7ed, 0x1e7ee,
@@ -1523,10 +1545,10 @@ static const OnigCodePoint CR_Graph[] = {
 	0x1f250, 0x1f251,
 	0x1f260, 0x1f265,
 	0x1f300, 0x1f6d7,
-	0x1f6dd, 0x1f6ec,
+	0x1f6dc, 0x1f6ec,
 	0x1f6f0, 0x1f6fc,
-	0x1f700, 0x1f773,
-	0x1f780, 0x1f7d8,
+	0x1f700, 0x1f776,
+	0x1f77b, 0x1f7d9,
 	0x1f7e0, 0x1f7eb,
 	0x1f7f0, 0x1f7f0,
 	0x1f800, 0x1f80b,
@@ -1537,25 +1559,24 @@ static const OnigCodePoint CR_Graph[] = {
 	0x1f8b0, 0x1f8b1,
 	0x1f900, 0x1fa53,
 	0x1fa60, 0x1fa6d,
-	0x1fa70, 0x1fa74,
-	0x1fa78, 0x1fa7c,
-	0x1fa80, 0x1fa86,
-	0x1fa90, 0x1faac,
-	0x1fab0, 0x1faba,
-	0x1fac0, 0x1fac5,
-	0x1fad0, 0x1fad9,
-	0x1fae0, 0x1fae7,
-	0x1faf0, 0x1faf6,
+	0x1fa70, 0x1fa7c,
+	0x1fa80, 0x1fa88,
+	0x1fa90, 0x1fabd,
+	0x1fabf, 0x1fac5,
+	0x1face, 0x1fadb,
+	0x1fae0, 0x1fae8,
+	0x1faf0, 0x1faf8,
 	0x1fb00, 0x1fb92,
 	0x1fb94, 0x1fbca,
 	0x1fbf0, 0x1fbf9,
 	0x20000, 0x2a6df,
-	0x2a700, 0x2b738,
+	0x2a700, 0x2b739,
 	0x2b740, 0x2b81d,
 	0x2b820, 0x2cea1,
 	0x2ceb0, 0x2ebe0,
 	0x2f800, 0x2fa1d,
 	0x30000, 0x3134a,
+	0x31350, 0x323af,
 	0xe0001, 0xe0001,
 	0xe0020, 0xe007f,
 	0xe0100, 0xe01ef,
@@ -1565,7 +1586,7 @@ static const OnigCodePoint CR_Graph[] = {
 
 /* 'Lower': [[:Lower:]] */
 static const OnigCodePoint CR_Lower[] = {
-	664,
+	671,
 	0x0061, 0x007a,
 	0x00aa, 0x00aa,
 	0x00b5, 0x00b5,
@@ -1842,7 +1863,7 @@ static const OnigCodePoint CR_Lower[] = {
 	0x052f, 0x052f,
 	0x0560, 0x0588,
 	0x10d0, 0x10fa,
-	0x10fd, 0x10ff,
+	0x10fc, 0x10ff,
 	0x13f8, 0x13fd,
 	0x1c80, 0x1c88,
 	0x1d00, 0x1dbf,
@@ -2182,10 +2203,11 @@ static const OnigCodePoint CR_Lower[] = {
 	0xa7d5, 0xa7d5,
 	0xa7d7, 0xa7d7,
 	0xa7d9, 0xa7d9,
+	0xa7f2, 0xa7f4,
 	0xa7f6, 0xa7f6,
 	0xa7f8, 0xa7fa,
 	0xab30, 0xab5a,
-	0xab5c, 0xab68,
+	0xab5c, 0xab69,
 	0xab70, 0xabbf,
 	0xfb00, 0xfb06,
 	0xfb13, 0xfb17,
@@ -2196,6 +2218,10 @@ static const OnigCodePoint CR_Lower[] = {
 	0x105a3, 0x105b1,
 	0x105b3, 0x105b9,
 	0x105bb, 0x105bc,
+	0x10780, 0x10780,
+	0x10783, 0x10785,
+	0x10787, 0x107b0,
+	0x107b2, 0x107ba,
 	0x10cc0, 0x10cf2,
 	0x118c0, 0x118df,
 	0x16e60, 0x16e7f,
@@ -2229,12 +2255,14 @@ static const OnigCodePoint CR_Lower[] = {
 	0x1d7cb, 0x1d7cb,
 	0x1df00, 0x1df09,
 	0x1df0b, 0x1df1e,
+	0x1df25, 0x1df2a,
+	0x1e030, 0x1e06d,
 	0x1e922, 0x1e943,
 }; /* CR_Lower */
 
 /* 'Print': [[:Print:]] */
 static const OnigCodePoint CR_Print[] = {
-	700,
+	709,
 	0x0020, 0x007e,
 	0x00a0, 0x0377,
 	0x037a, 0x037f,
@@ -2357,7 +2385,7 @@ static const OnigCodePoint CR_Print[] = {
 	0x0cdd, 0x0cde,
 	0x0ce0, 0x0ce3,
 	0x0ce6, 0x0cef,
-	0x0cf1, 0x0cf2,
+	0x0cf1, 0x0cf3,
 	0x0d00, 0x0d0c,
 	0x0d0e, 0x0d10,
 	0x0d12, 0x0d44,
@@ -2387,7 +2415,7 @@ static const OnigCodePoint CR_Print[] = {
 	0x0ea7, 0x0ebd,
 	0x0ec0, 0x0ec4,
 	0x0ec6, 0x0ec6,
-	0x0ec8, 0x0ecd,
+	0x0ec8, 0x0ece,
 	0x0ed0, 0x0ed9,
 	0x0edc, 0x0edf,
 	0x0f00, 0x0f47,
@@ -2659,7 +2687,7 @@ static const OnigCodePoint CR_Print[] = {
 	0x10e80, 0x10ea9,
 	0x10eab, 0x10ead,
 	0x10eb0, 0x10eb1,
-	0x10f00, 0x10f27,
+	0x10efd, 0x10f27,
 	0x10f30, 0x10f59,
 	0x10f70, 0x10f89,
 	0x10fb0, 0x10fcb,
@@ -2676,7 +2704,7 @@ static const OnigCodePoint CR_Print[] = {
 	0x11180, 0x111df,
 	0x111e1, 0x111f4,
 	0x11200, 0x11211,
-	0x11213, 0x1123e,
+	0x11213, 0x11241,
 	0x11280, 0x11286,
 	0x11288, 0x11288,
 	0x1128a, 0x1128d,
@@ -2729,6 +2757,7 @@ static const OnigCodePoint CR_Print[] = {
 	0x11a00, 0x11a47,
 	0x11a50, 0x11aa2,
 	0x11ab0, 0x11af8,
+	0x11b00, 0x11b09,
 	0x11c00, 0x11c08,
 	0x11c0a, 0x11c36,
 	0x11c38, 0x11c45,
@@ -2750,6 +2779,9 @@ static const OnigCodePoint CR_Print[] = {
 	0x11d93, 0x11d98,
 	0x11da0, 0x11da9,
 	0x11ee0, 0x11ef8,
+	0x11f00, 0x11f10,
+	0x11f12, 0x11f3a,
+	0x11f3e, 0x11f59,
 	0x11fb0, 0x11fb0,
 	0x11fc0, 0x11ff1,
 	0x11fff, 0x12399,
@@ -2757,8 +2789,7 @@ static const OnigCodePoint CR_Print[] = {
 	0x12470, 0x12474,
 	0x12480, 0x12543,
 	0x12f90, 0x12ff2,
-	0x13000, 0x1342e,
-	0x13430, 0x13438,
+	0x13000, 0x13455,
 	0x14400, 0x14646,
 	0x16800, 0x16a38,
 	0x16a40, 0x16a5e,
@@ -2785,7 +2816,9 @@ static const OnigCodePoint CR_Print[] = {
 	0x1aff5, 0x1affb,
 	0x1affd, 0x1affe,
 	0x1b000, 0x1b122,
+	0x1b132, 0x1b132,
 	0x1b150, 0x1b152,
+	0x1b155, 0x1b155,
 	0x1b164, 0x1b167,
 	0x1b170, 0x1b2fb,
 	0x1bc00, 0x1bc6a,
@@ -2800,6 +2833,7 @@ static const OnigCodePoint CR_Print[] = {
 	0x1d100, 0x1d126,
 	0x1d129, 0x1d1ea,
 	0x1d200, 0x1d245,
+	0x1d2c0, 0x1d2d3,
 	0x1d2e0, 0x1d2f3,
 	0x1d300, 0x1d356,
 	0x1d360, 0x1d378,
@@ -2827,11 +2861,14 @@ static const OnigCodePoint CR_Print[] = {
 	0x1da9b, 0x1da9f,
 	0x1daa1, 0x1daaf,
 	0x1df00, 0x1df1e,
+	0x1df25, 0x1df2a,
 	0x1e000, 0x1e006,
 	0x1e008, 0x1e018,
 	0x1e01b, 0x1e021,
 	0x1e023, 0x1e024,
 	0x1e026, 0x1e02a,
+	0x1e030, 0x1e06d,
+	0x1e08f, 0x1e08f,
 	0x1e100, 0x1e12c,
 	0x1e130, 0x1e13d,
 	0x1e140, 0x1e149,
@@ -2839,6 +2876,7 @@ static const OnigCodePoint CR_Print[] = {
 	0x1e290, 0x1e2ae,
 	0x1e2c0, 0x1e2f9,
 	0x1e2ff, 0x1e2ff,
+	0x1e4d0, 0x1e4f9,
 	0x1e7e0, 0x1e7e6,
 	0x1e7e8, 0x1e7eb,
 	0x1e7ed, 0x1e7ee,
@@ -2897,10 +2935,10 @@ static const OnigCodePoint CR_Print[] = {
 	0x1f250, 0x1f251,
 	0x1f260, 0x1f265,
 	0x1f300, 0x1f6d7,
-	0x1f6dd, 0x1f6ec,
+	0x1f6dc, 0x1f6ec,
 	0x1f6f0, 0x1f6fc,
-	0x1f700, 0x1f773,
-	0x1f780, 0x1f7d8,
+	0x1f700, 0x1f776,
+	0x1f77b, 0x1f7d9,
 	0x1f7e0, 0x1f7eb,
 	0x1f7f0, 0x1f7f0,
 	0x1f800, 0x1f80b,
@@ -2911,25 +2949,24 @@ static const OnigCodePoint CR_Print[] = {
 	0x1f8b0, 0x1f8b1,
 	0x1f900, 0x1fa53,
 	0x1fa60, 0x1fa6d,
-	0x1fa70, 0x1fa74,
-	0x1fa78, 0x1fa7c,
-	0x1fa80, 0x1fa86,
-	0x1fa90, 0x1faac,
-	0x1fab0, 0x1faba,
-	0x1fac0, 0x1fac5,
-	0x1fad0, 0x1fad9,
-	0x1fae0, 0x1fae7,
-	0x1faf0, 0x1faf6,
+	0x1fa70, 0x1fa7c,
+	0x1fa80, 0x1fa88,
+	0x1fa90, 0x1fabd,
+	0x1fabf, 0x1fac5,
+	0x1face, 0x1fadb,
+	0x1fae0, 0x1fae8,
+	0x1faf0, 0x1faf8,
 	0x1fb00, 0x1fb92,
 	0x1fb94, 0x1fbca,
 	0x1fbf0, 0x1fbf9,
 	0x20000, 0x2a6df,
-	0x2a700, 0x2b738,
+	0x2a700, 0x2b739,
 	0x2b740, 0x2b81d,
 	0x2b820, 0x2cea1,
 	0x2ceb0, 0x2ebe0,
 	0x2f800, 0x2fa1d,
 	0x30000, 0x3134a,
+	0x31350, 0x323af,
 	0xe0001, 0xe0001,
 	0xe0020, 0xe007f,
 	0xe0100, 0xe01ef,
@@ -2939,7 +2976,7 @@ static const OnigCodePoint CR_Print[] = {
 
 /* 'XPosixPunct': [[:Punct:]] */
 static const OnigCodePoint CR_XPosixPunct[] = {
-	184,
+	186,
 	0x0021, 0x002f,
 	0x003a, 0x0040,
 	0x005b, 0x0060,
@@ -3109,9 +3146,11 @@ static const OnigCodePoint CR_XPosixPunct[] = {
 	0x11a3f, 0x11a46,
 	0x11a9a, 0x11a9c,
 	0x11a9e, 0x11aa2,
+	0x11b00, 0x11b09,
 	0x11c41, 0x11c45,
 	0x11c70, 0x11c71,
 	0x11ef7, 0x11ef8,
+	0x11f43, 0x11f4f,
 	0x11fff, 0x11fff,
 	0x12470, 0x12474,
 	0x12ff1, 0x12ff2,
@@ -3807,7 +3846,7 @@ static const OnigCodePoint CR_XDigit[] = {
 
 /* 'Word': [[:Word:]] */
 static const OnigCodePoint CR_Word[] = {
-	758,
+	770,
 	0x0030, 0x0039,
 	0x0041, 0x005a,
 	0x005f, 0x005f,
@@ -3965,7 +4004,7 @@ static const OnigCodePoint CR_Word[] = {
 	0x0cdd, 0x0cde,
 	0x0ce0, 0x0ce3,
 	0x0ce6, 0x0cef,
-	0x0cf1, 0x0cf2,
+	0x0cf1, 0x0cf3,
 	0x0d00, 0x0d0c,
 	0x0d0e, 0x0d10,
 	0x0d12, 0x0d44,
@@ -3998,7 +4037,7 @@ static const OnigCodePoint CR_Word[] = {
 	0x0ea7, 0x0ebd,
 	0x0ec0, 0x0ec4,
 	0x0ec6, 0x0ec6,
-	0x0ec8, 0x0ecd,
+	0x0ec8, 0x0ece,
 	0x0ed0, 0x0ed9,
 	0x0edc, 0x0edf,
 	0x0f00, 0x0f00,
@@ -4311,7 +4350,7 @@ static const OnigCodePoint CR_Word[] = {
 	0x10e80, 0x10ea9,
 	0x10eab, 0x10eac,
 	0x10eb0, 0x10eb1,
-	0x10f00, 0x10f1c,
+	0x10efd, 0x10f1c,
 	0x10f27, 0x10f27,
 	0x10f30, 0x10f50,
 	0x10f70, 0x10f85,
@@ -4334,7 +4373,7 @@ static const OnigCodePoint CR_Word[] = {
 	0x111dc, 0x111dc,
 	0x11200, 0x11211,
 	0x11213, 0x11237,
-	0x1123e, 0x1123e,
+	0x1123e, 0x11241,
 	0x11280, 0x11286,
 	0x11288, 0x11288,
 	0x1128a, 0x1128d,
@@ -4415,12 +4454,17 @@ static const OnigCodePoint CR_Word[] = {
 	0x11d93, 0x11d98,
 	0x11da0, 0x11da9,
 	0x11ee0, 0x11ef6,
+	0x11f00, 0x11f10,
+	0x11f12, 0x11f3a,
+	0x11f3e, 0x11f42,
+	0x11f50, 0x11f59,
 	0x11fb0, 0x11fb0,
 	0x12000, 0x12399,
 	0x12400, 0x1246e,
 	0x12480, 0x12543,
 	0x12f90, 0x12ff0,
-	0x13000, 0x1342e,
+	0x13000, 0x1342f,
+	0x13440, 0x13455,
 	0x14400, 0x14646,
 	0x16800, 0x16a38,
 	0x16a40, 0x16a5e,
@@ -4448,7 +4492,9 @@ static const OnigCodePoint CR_Word[] = {
 	0x1aff5, 0x1affb,
 	0x1affd, 0x1affe,
 	0x1b000, 0x1b122,
+	0x1b132, 0x1b132,
 	0x1b150, 0x1b152,
+	0x1b155, 0x1b155,
 	0x1b164, 0x1b167,
 	0x1b170, 0x1b2fb,
 	0x1bc00, 0x1bc6a,
@@ -4502,17 +4548,21 @@ static const OnigCodePoint CR_Word[] = {
 	0x1da9b, 0x1da9f,
 	0x1daa1, 0x1daaf,
 	0x1df00, 0x1df1e,
+	0x1df25, 0x1df2a,
 	0x1e000, 0x1e006,
 	0x1e008, 0x1e018,
 	0x1e01b, 0x1e021,
 	0x1e023, 0x1e024,
 	0x1e026, 0x1e02a,
+	0x1e030, 0x1e06d,
+	0x1e08f, 0x1e08f,
 	0x1e100, 0x1e12c,
 	0x1e130, 0x1e13d,
 	0x1e140, 0x1e149,
 	0x1e14e, 0x1e14e,
 	0x1e290, 0x1e2ae,
 	0x1e2c0, 0x1e2f9,
+	0x1e4d0, 0x1e4f9,
 	0x1e7e0, 0x1e7e6,
 	0x1e7e8, 0x1e7eb,
 	0x1e7ed, 0x1e7ee,
@@ -4559,18 +4609,19 @@ static const OnigCodePoint CR_Word[] = {
 	0x1f170, 0x1f189,
 	0x1fbf0, 0x1fbf9,
 	0x20000, 0x2a6df,
-	0x2a700, 0x2b738,
+	0x2a700, 0x2b739,
 	0x2b740, 0x2b81d,
 	0x2b820, 0x2cea1,
 	0x2ceb0, 0x2ebe0,
 	0x2f800, 0x2fa1d,
 	0x30000, 0x3134a,
+	0x31350, 0x323af,
 	0xe0100, 0xe01ef,
 }; /* CR_Word */
 
 /* 'Alnum': [[:Alnum:]] */
 static const OnigCodePoint CR_Alnum[] = {
-	760,
+	772,
 	0x0030, 0x0039,
 	0x0041, 0x005a,
 	0x0061, 0x007a,
@@ -4709,8 +4760,7 @@ static const OnigCodePoint CR_Alnum[] = {
 	0x0bd0, 0x0bd0,
 	0x0bd7, 0x0bd7,
 	0x0be6, 0x0bef,
-	0x0c00, 0x0c03,
-	0x0c05, 0x0c0c,
+	0x0c00, 0x0c0c,
 	0x0c0e, 0x0c10,
 	0x0c12, 0x0c28,
 	0x0c2a, 0x0c39,
@@ -4735,7 +4785,7 @@ static const OnigCodePoint CR_Alnum[] = {
 	0x0cdd, 0x0cde,
 	0x0ce0, 0x0ce3,
 	0x0ce6, 0x0cef,
-	0x0cf1, 0x0cf2,
+	0x0cf1, 0x0cf3,
 	0x0d00, 0x0d0c,
 	0x0d0e, 0x0d10,
 	0x0d12, 0x0d3a,
@@ -4778,7 +4828,7 @@ static const OnigCodePoint CR_Alnum[] = {
 	0x0f20, 0x0f29,
 	0x0f40, 0x0f47,
 	0x0f49, 0x0f6c,
-	0x0f71, 0x0f81,
+	0x0f71, 0x0f83,
 	0x0f88, 0x0f97,
 	0x0f99, 0x0fbc,
 	0x1000, 0x1036,
@@ -5088,7 +5138,7 @@ static const OnigCodePoint CR_Alnum[] = {
 	0x11000, 0x11045,
 	0x11066, 0x1106f,
 	0x11071, 0x11075,
-	0x11082, 0x110b8,
+	0x11080, 0x110b8,
 	0x110c2, 0x110c2,
 	0x110d0, 0x110e8,
 	0x110f0, 0x110f9,
@@ -5104,7 +5154,7 @@ static const OnigCodePoint CR_Alnum[] = {
 	0x11200, 0x11211,
 	0x11213, 0x11234,
 	0x11237, 0x11237,
-	0x1123e, 0x1123e,
+	0x1123e, 0x11241,
 	0x11280, 0x11286,
 	0x11288, 0x11288,
 	0x1128a, 0x1128d,
@@ -5194,12 +5244,17 @@ static const OnigCodePoint CR_Alnum[] = {
 	0x11d98, 0x11d98,
 	0x11da0, 0x11da9,
 	0x11ee0, 0x11ef6,
+	0x11f00, 0x11f10,
+	0x11f12, 0x11f3a,
+	0x11f3e, 0x11f40,
+	0x11f50, 0x11f59,
 	0x11fb0, 0x11fb0,
 	0x12000, 0x12399,
 	0x12400, 0x1246e,
 	0x12480, 0x12543,
 	0x12f90, 0x12ff0,
-	0x13000, 0x1342e,
+	0x13000, 0x1342f,
+	0x13441, 0x13446,
 	0x14400, 0x14646,
 	0x16800, 0x16a38,
 	0x16a40, 0x16a5e,
@@ -5226,7 +5281,9 @@ static const OnigCodePoint CR_Alnum[] = {
 	0x1aff5, 0x1affb,
 	0x1affd, 0x1affe,
 	0x1b000, 0x1b122,
+	0x1b132, 0x1b132,
 	0x1b150, 0x1b152,
+	0x1b155, 0x1b155,
 	0x1b164, 0x1b167,
 	0x1b170, 0x1b2fb,
 	0x1bc00, 0x1bc6a,
@@ -5266,11 +5323,14 @@ static const OnigCodePoint CR_Alnum[] = {
 	0x1d7c4, 0x1d7cb,
 	0x1d7ce, 0x1d7ff,
 	0x1df00, 0x1df1e,
+	0x1df25, 0x1df2a,
 	0x1e000, 0x1e006,
 	0x1e008, 0x1e018,
 	0x1e01b, 0x1e021,
 	0x1e023, 0x1e024,
 	0x1e026, 0x1e02a,
+	0x1e030, 0x1e06d,
+	0x1e08f, 0x1e08f,
 	0x1e100, 0x1e12c,
 	0x1e137, 0x1e13d,
 	0x1e140, 0x1e149,
@@ -5278,6 +5338,8 @@ static const OnigCodePoint CR_Alnum[] = {
 	0x1e290, 0x1e2ad,
 	0x1e2c0, 0x1e2eb,
 	0x1e2f0, 0x1e2f9,
+	0x1e4d0, 0x1e4eb,
+	0x1e4f0, 0x1e4f9,
 	0x1e7e0, 0x1e7e6,
 	0x1e7e8, 0x1e7eb,
 	0x1e7ed, 0x1e7ee,
@@ -5325,12 +5387,13 @@ static const OnigCodePoint CR_Alnum[] = {
 	0x1f170, 0x1f189,
 	0x1fbf0, 0x1fbf9,
 	0x20000, 0x2a6df,
-	0x2a700, 0x2b738,
+	0x2a700, 0x2b739,
 	0x2b740, 0x2b81d,
 	0x2b820, 0x2cea1,
 	0x2ceb0, 0x2ebe0,
 	0x2f800, 0x2fa1d,
 	0x30000, 0x3134a,
+	0x31350, 0x323af,
 }; /* CR_Alnum */
 
 /* 'ASCII': [[:ASCII:]] */
@@ -5341,7 +5404,7 @@ static const OnigCodePoint CR_ASCII[] = {
 
 /* 'Punct' */
 static const OnigCodePoint CR_Punct[] = {
-	189,
+	191,
 	0x0021, 0x0023,
 	0x0025, 0x002a,
 	0x002c, 0x002f,
@@ -5516,9 +5579,11 @@ static const OnigCodePoint CR_Punct[] = {
 	0x11a3f, 0x11a46,
 	0x11a9a, 0x11a9c,
 	0x11a9e, 0x11aa2,
+	0x11b00, 0x11b09,
 	0x11c41, 0x11c45,
 	0x11c70, 0x11c71,
 	0x11ef7, 0x11ef8,
+	0x11f43, 0x11f4f,
 	0x11fff, 0x11fff,
 	0x12470, 0x12474,
 	0x12ff1, 0x12ff2,
@@ -5542,7 +5607,7 @@ static const OnigCodePoint CR_Any[] = {
 
 /* 'Assigned': - */
 static const OnigCodePoint CR_Assigned[] = {
-	698,
+	707,
 	0x0000, 0x0377,
 	0x037a, 0x037f,
 	0x0384, 0x038a,
@@ -5664,7 +5729,7 @@ static const OnigCodePoint CR_Assigned[] = {
 	0x0cdd, 0x0cde,
 	0x0ce0, 0x0ce3,
 	0x0ce6, 0x0cef,
-	0x0cf1, 0x0cf2,
+	0x0cf1, 0x0cf3,
 	0x0d00, 0x0d0c,
 	0x0d0e, 0x0d10,
 	0x0d12, 0x0d44,
@@ -5694,7 +5759,7 @@ static const OnigCodePoint CR_Assigned[] = {
 	0x0ea7, 0x0ebd,
 	0x0ec0, 0x0ec4,
 	0x0ec6, 0x0ec6,
-	0x0ec8, 0x0ecd,
+	0x0ec8, 0x0ece,
 	0x0ed0, 0x0ed9,
 	0x0edc, 0x0edf,
 	0x0f00, 0x0f47,
@@ -5965,7 +6030,7 @@ static const OnigCodePoint CR_Assigned[] = {
 	0x10e80, 0x10ea9,
 	0x10eab, 0x10ead,
 	0x10eb0, 0x10eb1,
-	0x10f00, 0x10f27,
+	0x10efd, 0x10f27,
 	0x10f30, 0x10f59,
 	0x10f70, 0x10f89,
 	0x10fb0, 0x10fcb,
@@ -5982,7 +6047,7 @@ static const OnigCodePoint CR_Assigned[] = {
 	0x11180, 0x111df,
 	0x111e1, 0x111f4,
 	0x11200, 0x11211,
-	0x11213, 0x1123e,
+	0x11213, 0x11241,
 	0x11280, 0x11286,
 	0x11288, 0x11288,
 	0x1128a, 0x1128d,
@@ -6035,6 +6100,7 @@ static const OnigCodePoint CR_Assigned[] = {
 	0x11a00, 0x11a47,
 	0x11a50, 0x11aa2,
 	0x11ab0, 0x11af8,
+	0x11b00, 0x11b09,
 	0x11c00, 0x11c08,
 	0x11c0a, 0x11c36,
 	0x11c38, 0x11c45,
@@ -6056,6 +6122,9 @@ static const OnigCodePoint CR_Assigned[] = {
 	0x11d93, 0x11d98,
 	0x11da0, 0x11da9,
 	0x11ee0, 0x11ef8,
+	0x11f00, 0x11f10,
+	0x11f12, 0x11f3a,
+	0x11f3e, 0x11f59,
 	0x11fb0, 0x11fb0,
 	0x11fc0, 0x11ff1,
 	0x11fff, 0x12399,
@@ -6063,8 +6132,7 @@ static const OnigCodePoint CR_Assigned[] = {
 	0x12470, 0x12474,
 	0x12480, 0x12543,
 	0x12f90, 0x12ff2,
-	0x13000, 0x1342e,
-	0x13430, 0x13438,
+	0x13000, 0x13455,
 	0x14400, 0x14646,
 	0x16800, 0x16a38,
 	0x16a40, 0x16a5e,
@@ -6091,7 +6159,9 @@ static const OnigCodePoint CR_Assigned[] = {
 	0x1aff5, 0x1affb,
 	0x1affd, 0x1affe,
 	0x1b000, 0x1b122,
+	0x1b132, 0x1b132,
 	0x1b150, 0x1b152,
+	0x1b155, 0x1b155,
 	0x1b164, 0x1b167,
 	0x1b170, 0x1b2fb,
 	0x1bc00, 0x1bc6a,
@@ -6106,6 +6176,7 @@ static const OnigCodePoint CR_Assigned[] = {
 	0x1d100, 0x1d126,
 	0x1d129, 0x1d1ea,
 	0x1d200, 0x1d245,
+	0x1d2c0, 0x1d2d3,
 	0x1d2e0, 0x1d2f3,
 	0x1d300, 0x1d356,
 	0x1d360, 0x1d378,
@@ -6133,11 +6204,14 @@ static const OnigCodePoint CR_Assigned[] = {
 	0x1da9b, 0x1da9f,
 	0x1daa1, 0x1daaf,
 	0x1df00, 0x1df1e,
+	0x1df25, 0x1df2a,
 	0x1e000, 0x1e006,
 	0x1e008, 0x1e018,
 	0x1e01b, 0x1e021,
 	0x1e023, 0x1e024,
 	0x1e026, 0x1e02a,
+	0x1e030, 0x1e06d,
+	0x1e08f, 0x1e08f,
 	0x1e100, 0x1e12c,
 	0x1e130, 0x1e13d,
 	0x1e140, 0x1e149,
@@ -6145,6 +6219,7 @@ static const OnigCodePoint CR_Assigned[] = {
 	0x1e290, 0x1e2ae,
 	0x1e2c0, 0x1e2f9,
 	0x1e2ff, 0x1e2ff,
+	0x1e4d0, 0x1e4f9,
 	0x1e7e0, 0x1e7e6,
 	0x1e7e8, 0x1e7eb,
 	0x1e7ed, 0x1e7ee,
@@ -6203,10 +6278,10 @@ static const OnigCodePoint CR_Assigned[] = {
 	0x1f250, 0x1f251,
 	0x1f260, 0x1f265,
 	0x1f300, 0x1f6d7,
-	0x1f6dd, 0x1f6ec,
+	0x1f6dc, 0x1f6ec,
 	0x1f6f0, 0x1f6fc,
-	0x1f700, 0x1f773,
-	0x1f780, 0x1f7d8,
+	0x1f700, 0x1f776,
+	0x1f77b, 0x1f7d9,
 	0x1f7e0, 0x1f7eb,
 	0x1f7f0, 0x1f7f0,
 	0x1f800, 0x1f80b,
@@ -6217,25 +6292,24 @@ static const OnigCodePoint CR_Assigned[] = {
 	0x1f8b0, 0x1f8b1,
 	0x1f900, 0x1fa53,
 	0x1fa60, 0x1fa6d,
-	0x1fa70, 0x1fa74,
-	0x1fa78, 0x1fa7c,
-	0x1fa80, 0x1fa86,
-	0x1fa90, 0x1faac,
-	0x1fab0, 0x1faba,
-	0x1fac0, 0x1fac5,
-	0x1fad0, 0x1fad9,
-	0x1fae0, 0x1fae7,
-	0x1faf0, 0x1faf6,
+	0x1fa70, 0x1fa7c,
+	0x1fa80, 0x1fa88,
+	0x1fa90, 0x1fabd,
+	0x1fabf, 0x1fac5,
+	0x1face, 0x1fadb,
+	0x1fae0, 0x1fae8,
+	0x1faf0, 0x1faf8,
 	0x1fb00, 0x1fb92,
 	0x1fb94, 0x1fbca,
 	0x1fbf0, 0x1fbf9,
 	0x20000, 0x2a6df,
-	0x2a700, 0x2b738,
+	0x2a700, 0x2b739,
 	0x2b740, 0x2b81d,
 	0x2b820, 0x2cea1,
 	0x2ceb0, 0x2ebe0,
 	0x2f800, 0x2fa1d,
 	0x30000, 0x3134a,
+	0x31350, 0x323af,
 	0xe0001, 0xe0001,
 	0xe0020, 0xe007f,
 	0xe0100, 0xe01ef,
@@ -6245,7 +6319,7 @@ static const OnigCodePoint CR_Assigned[] = {
 
 /* 'C': Major Category */
 static const OnigCodePoint CR_C[] = {
-	701,
+	712,
 	0x0000, 0x001f,
 	0x007f, 0x009f,
 	0x00ad, 0x00ad,
@@ -6372,7 +6446,7 @@ static const OnigCodePoint CR_C[] = {
 	0x0cdf, 0x0cdf,
 	0x0ce4, 0x0ce5,
 	0x0cf0, 0x0cf0,
-	0x0cf3, 0x0cff,
+	0x0cf4, 0x0cff,
 	0x0d0d, 0x0d0d,
 	0x0d11, 0x0d11,
 	0x0d45, 0x0d45,
@@ -6402,7 +6476,7 @@ static const OnigCodePoint CR_C[] = {
 	0x0ebe, 0x0ebf,
 	0x0ec5, 0x0ec5,
 	0x0ec7, 0x0ec7,
-	0x0ece, 0x0ecf,
+	0x0ecf, 0x0ecf,
 	0x0eda, 0x0edb,
 	0x0ee0, 0x0eff,
 	0x0f48, 0x0f48,
@@ -6674,7 +6748,7 @@ static const OnigCodePoint CR_C[] = {
 	0x10e7f, 0x10e7f,
 	0x10eaa, 0x10eaa,
 	0x10eae, 0x10eaf,
-	0x10eb2, 0x10eff,
+	0x10eb2, 0x10efc,
 	0x10f28, 0x10f2f,
 	0x10f5a, 0x10f6f,
 	0x10f8a, 0x10faf,
@@ -6692,7 +6766,7 @@ static const OnigCodePoint CR_C[] = {
 	0x111e0, 0x111e0,
 	0x111f5, 0x111ff,
 	0x11212, 0x11212,
-	0x1123f, 0x1127f,
+	0x11242, 0x1127f,
 	0x11287, 0x11287,
 	0x11289, 0x11289,
 	0x1128e, 0x1128e,
@@ -6744,7 +6818,8 @@ static const OnigCodePoint CR_C[] = {
 	0x119e5, 0x119ff,
 	0x11a48, 0x11a4f,
 	0x11aa3, 0x11aaf,
-	0x11af9, 0x11bff,
+	0x11af9, 0x11aff,
+	0x11b0a, 0x11bff,
 	0x11c09, 0x11c09,
 	0x11c37, 0x11c37,
 	0x11c46, 0x11c4f,
@@ -6765,7 +6840,10 @@ static const OnigCodePoint CR_C[] = {
 	0x11d92, 0x11d92,
 	0x11d99, 0x11d9f,
 	0x11daa, 0x11edf,
-	0x11ef9, 0x11faf,
+	0x11ef9, 0x11eff,
+	0x11f11, 0x11f11,
+	0x11f3b, 0x11f3d,
+	0x11f5a, 0x11faf,
 	0x11fb1, 0x11fbf,
 	0x11ff2, 0x11ffe,
 	0x1239a, 0x123ff,
@@ -6773,7 +6851,8 @@ static const OnigCodePoint CR_C[] = {
 	0x12475, 0x1247f,
 	0x12544, 0x12f8f,
 	0x12ff3, 0x12fff,
-	0x1342f, 0x143ff,
+	0x13430, 0x1343f,
+	0x13456, 0x143ff,
 	0x14647, 0x167ff,
 	0x16a39, 0x16a3f,
 	0x16a5f, 0x16a5f,
@@ -6799,8 +6878,10 @@ static const OnigCodePoint CR_C[] = {
 	0x1aff4, 0x1aff4,
 	0x1affc, 0x1affc,
 	0x1afff, 0x1afff,
-	0x1b123, 0x1b14f,
-	0x1b153, 0x1b163,
+	0x1b123, 0x1b131,
+	0x1b133, 0x1b14f,
+	0x1b153, 0x1b154,
+	0x1b156, 0x1b163,
 	0x1b168, 0x1b16f,
 	0x1b2fc, 0x1bbff,
 	0x1bc6b, 0x1bc6f,
@@ -6815,7 +6896,8 @@ static const OnigCodePoint CR_C[] = {
 	0x1d127, 0x1d128,
 	0x1d173, 0x1d17a,
 	0x1d1eb, 0x1d1ff,
-	0x1d246, 0x1d2df,
+	0x1d246, 0x1d2bf,
+	0x1d2d4, 0x1d2df,
 	0x1d2f4, 0x1d2ff,
 	0x1d357, 0x1d35f,
 	0x1d379, 0x1d3ff,
@@ -6842,19 +6924,23 @@ static const OnigCodePoint CR_C[] = {
 	0x1da8c, 0x1da9a,
 	0x1daa0, 0x1daa0,
 	0x1dab0, 0x1deff,
-	0x1df1f, 0x1dfff,
+	0x1df1f, 0x1df24,
+	0x1df2b, 0x1dfff,
 	0x1e007, 0x1e007,
 	0x1e019, 0x1e01a,
 	0x1e022, 0x1e022,
 	0x1e025, 0x1e025,
-	0x1e02b, 0x1e0ff,
+	0x1e02b, 0x1e02f,
+	0x1e06e, 0x1e08e,
+	0x1e090, 0x1e0ff,
 	0x1e12d, 0x1e12f,
 	0x1e13e, 0x1e13f,
 	0x1e14a, 0x1e14d,
 	0x1e150, 0x1e28f,
 	0x1e2af, 0x1e2bf,
 	0x1e2fa, 0x1e2fe,
-	0x1e300, 0x1e7df,
+	0x1e300, 0x1e4cf,
+	0x1e4fa, 0x1e7df,
 	0x1e7e7, 0x1e7e7,
 	0x1e7ec, 0x1e7ec,
 	0x1e7ef, 0x1e7ef,
@@ -6912,11 +6998,11 @@ static const OnigCodePoint CR_C[] = {
 	0x1f249, 0x1f24f,
 	0x1f252, 0x1f25f,
 	0x1f266, 0x1f2ff,
-	0x1f6d8, 0x1f6dc,
+	0x1f6d8, 0x1f6db,
 	0x1f6ed, 0x1f6ef,
 	0x1f6fd, 0x1f6ff,
-	0x1f774, 0x1f77f,
-	0x1f7d9, 0x1f7df,
+	0x1f777, 0x1f77a,
+	0x1f7da, 0x1f7df,
 	0x1f7ec, 0x1f7ef,
 	0x1f7f1, 0x1f7ff,
 	0x1f80c, 0x1f80f,
@@ -6927,25 +7013,24 @@ static const OnigCodePoint CR_C[] = {
 	0x1f8b2, 0x1f8ff,
 	0x1fa54, 0x1fa5f,
 	0x1fa6e, 0x1fa6f,
-	0x1fa75, 0x1fa77,
 	0x1fa7d, 0x1fa7f,
-	0x1fa87, 0x1fa8f,
-	0x1faad, 0x1faaf,
-	0x1fabb, 0x1fabf,
-	0x1fac6, 0x1facf,
-	0x1fada, 0x1fadf,
-	0x1fae8, 0x1faef,
-	0x1faf7, 0x1faff,
+	0x1fa89, 0x1fa8f,
+	0x1fabe, 0x1fabe,
+	0x1fac6, 0x1facd,
+	0x1fadc, 0x1fadf,
+	0x1fae9, 0x1faef,
+	0x1faf9, 0x1faff,
 	0x1fb93, 0x1fb93,
 	0x1fbcb, 0x1fbef,
 	0x1fbfa, 0x1ffff,
 	0x2a6e0, 0x2a6ff,
-	0x2b739, 0x2b73f,
+	0x2b73a, 0x2b73f,
 	0x2b81e, 0x2b81f,
 	0x2cea2, 0x2ceaf,
 	0x2ebe1, 0x2f7ff,
 	0x2fa1e, 0x2ffff,
-	0x3134b, 0xe00ff,
+	0x3134b, 0x3134f,
+	0x323b0, 0xe00ff,
 	0xe01f0, 0x10ffff,
 }; /* CR_C */
 
@@ -6971,7 +7056,7 @@ static const OnigCodePoint CR_Cf[] = {
 	0xfff9, 0xfffb,
 	0x110bd, 0x110bd,
 	0x110cd, 0x110cd,
-	0x13430, 0x13438,
+	0x13430, 0x1343f,
 	0x1bca0, 0x1bca3,
 	0x1d173, 0x1d17a,
 	0xe0001, 0xe0001,
@@ -6980,7 +7065,7 @@ static const OnigCodePoint CR_Cf[] = {
 
 /* 'Cn': General Category */
 static const OnigCodePoint CR_Cn[] = {
-	698,
+	707,
 	0x0378, 0x0379,
 	0x0380, 0x0383,
 	0x038b, 0x038b,
@@ -7102,7 +7187,7 @@ static const OnigCodePoint CR_Cn[] = {
 	0x0cdf, 0x0cdf,
 	0x0ce4, 0x0ce5,
 	0x0cf0, 0x0cf0,
-	0x0cf3, 0x0cff,
+	0x0cf4, 0x0cff,
 	0x0d0d, 0x0d0d,
 	0x0d11, 0x0d11,
 	0x0d45, 0x0d45,
@@ -7132,7 +7217,7 @@ static const OnigCodePoint CR_Cn[] = {
 	0x0ebe, 0x0ebf,
 	0x0ec5, 0x0ec5,
 	0x0ec7, 0x0ec7,
-	0x0ece, 0x0ecf,
+	0x0ecf, 0x0ecf,
 	0x0eda, 0x0edb,
 	0x0ee0, 0x0eff,
 	0x0f48, 0x0f48,
@@ -7402,7 +7487,7 @@ static const OnigCodePoint CR_Cn[] = {
 	0x10e7f, 0x10e7f,
 	0x10eaa, 0x10eaa,
 	0x10eae, 0x10eaf,
-	0x10eb2, 0x10eff,
+	0x10eb2, 0x10efc,
 	0x10f28, 0x10f2f,
 	0x10f5a, 0x10f6f,
 	0x10f8a, 0x10faf,
@@ -7420,7 +7505,7 @@ static const OnigCodePoint CR_Cn[] = {
 	0x111e0, 0x111e0,
 	0x111f5, 0x111ff,
 	0x11212, 0x11212,
-	0x1123f, 0x1127f,
+	0x11242, 0x1127f,
 	0x11287, 0x11287,
 	0x11289, 0x11289,
 	0x1128e, 0x1128e,
@@ -7472,7 +7557,8 @@ static const OnigCodePoint CR_Cn[] = {
 	0x119e5, 0x119ff,
 	0x11a48, 0x11a4f,
 	0x11aa3, 0x11aaf,
-	0x11af9, 0x11bff,
+	0x11af9, 0x11aff,
+	0x11b0a, 0x11bff,
 	0x11c09, 0x11c09,
 	0x11c37, 0x11c37,
 	0x11c46, 0x11c4f,
@@ -7493,7 +7579,10 @@ static const OnigCodePoint CR_Cn[] = {
 	0x11d92, 0x11d92,
 	0x11d99, 0x11d9f,
 	0x11daa, 0x11edf,
-	0x11ef9, 0x11faf,
+	0x11ef9, 0x11eff,
+	0x11f11, 0x11f11,
+	0x11f3b, 0x11f3d,
+	0x11f5a, 0x11faf,
 	0x11fb1, 0x11fbf,
 	0x11ff2, 0x11ffe,
 	0x1239a, 0x123ff,
@@ -7501,8 +7590,7 @@ static const OnigCodePoint CR_Cn[] = {
 	0x12475, 0x1247f,
 	0x12544, 0x12f8f,
 	0x12ff3, 0x12fff,
-	0x1342f, 0x1342f,
-	0x13439, 0x143ff,
+	0x13456, 0x143ff,
 	0x14647, 0x167ff,
 	0x16a39, 0x16a3f,
 	0x16a5f, 0x16a5f,
@@ -7528,8 +7616,10 @@ static const OnigCodePoint CR_Cn[] = {
 	0x1aff4, 0x1aff4,
 	0x1affc, 0x1affc,
 	0x1afff, 0x1afff,
-	0x1b123, 0x1b14f,
-	0x1b153, 0x1b163,
+	0x1b123, 0x1b131,
+	0x1b133, 0x1b14f,
+	0x1b153, 0x1b154,
+	0x1b156, 0x1b163,
 	0x1b168, 0x1b16f,
 	0x1b2fc, 0x1bbff,
 	0x1bc6b, 0x1bc6f,
@@ -7543,7 +7633,8 @@ static const OnigCodePoint CR_Cn[] = {
 	0x1d0f6, 0x1d0ff,
 	0x1d127, 0x1d128,
 	0x1d1eb, 0x1d1ff,
-	0x1d246, 0x1d2df,
+	0x1d246, 0x1d2bf,
+	0x1d2d4, 0x1d2df,
 	0x1d2f4, 0x1d2ff,
 	0x1d357, 0x1d35f,
 	0x1d379, 0x1d3ff,
@@ -7570,19 +7661,23 @@ static const OnigCodePoint CR_Cn[] = {
 	0x1da8c, 0x1da9a,
 	0x1daa0, 0x1daa0,
 	0x1dab0, 0x1deff,
-	0x1df1f, 0x1dfff,
+	0x1df1f, 0x1df24,
+	0x1df2b, 0x1dfff,
 	0x1e007, 0x1e007,
 	0x1e019, 0x1e01a,
 	0x1e022, 0x1e022,
 	0x1e025, 0x1e025,
-	0x1e02b, 0x1e0ff,
+	0x1e02b, 0x1e02f,
+	0x1e06e, 0x1e08e,
+	0x1e090, 0x1e0ff,
 	0x1e12d, 0x1e12f,
 	0x1e13e, 0x1e13f,
 	0x1e14a, 0x1e14d,
 	0x1e150, 0x1e28f,
 	0x1e2af, 0x1e2bf,
 	0x1e2fa, 0x1e2fe,
-	0x1e300, 0x1e7df,
+	0x1e300, 0x1e4cf,
+	0x1e4fa, 0x1e7df,
 	0x1e7e7, 0x1e7e7,
 	0x1e7ec, 0x1e7ec,
 	0x1e7ef, 0x1e7ef,
@@ -7640,11 +7735,11 @@ static const OnigCodePoint CR_Cn[] = {
 	0x1f249, 0x1f24f,
 	0x1f252, 0x1f25f,
 	0x1f266, 0x1f2ff,
-	0x1f6d8, 0x1f6dc,
+	0x1f6d8, 0x1f6db,
 	0x1f6ed, 0x1f6ef,
 	0x1f6fd, 0x1f6ff,
-	0x1f774, 0x1f77f,
-	0x1f7d9, 0x1f7df,
+	0x1f777, 0x1f77a,
+	0x1f7da, 0x1f7df,
 	0x1f7ec, 0x1f7ef,
 	0x1f7f1, 0x1f7ff,
 	0x1f80c, 0x1f80f,
@@ -7655,25 +7750,24 @@ static const OnigCodePoint CR_Cn[] = {
 	0x1f8b2, 0x1f8ff,
 	0x1fa54, 0x1fa5f,
 	0x1fa6e, 0x1fa6f,
-	0x1fa75, 0x1fa77,
 	0x1fa7d, 0x1fa7f,
-	0x1fa87, 0x1fa8f,
-	0x1faad, 0x1faaf,
-	0x1fabb, 0x1fabf,
-	0x1fac6, 0x1facf,
-	0x1fada, 0x1fadf,
-	0x1fae8, 0x1faef,
-	0x1faf7, 0x1faff,
+	0x1fa89, 0x1fa8f,
+	0x1fabe, 0x1fabe,
+	0x1fac6, 0x1facd,
+	0x1fadc, 0x1fadf,
+	0x1fae9, 0x1faef,
+	0x1faf9, 0x1faff,
 	0x1fb93, 0x1fb93,
 	0x1fbcb, 0x1fbef,
 	0x1fbfa, 0x1ffff,
 	0x2a6e0, 0x2a6ff,
-	0x2b739, 0x2b73f,
+	0x2b73a, 0x2b73f,
 	0x2b81e, 0x2b81f,
 	0x2cea2, 0x2ceaf,
 	0x2ebe1, 0x2f7ff,
 	0x2fa1e, 0x2ffff,
-	0x3134b, 0xe0000,
+	0x3134b, 0x3134f,
+	0x323b0, 0xe0000,
 	0xe0002, 0xe001f,
 	0xe0080, 0xe00ff,
 	0xe01f0, 0xeffff,
@@ -7697,7 +7791,7 @@ static const OnigCodePoint CR_Cs[] = {
 
 /* 'L': Major Category */
 static const OnigCodePoint CR_L[] = {
-	648,
+	659,
 	0x0041, 0x005a,
 	0x0061, 0x007a,
 	0x00aa, 0x00aa,
@@ -8167,6 +8261,7 @@ static const OnigCodePoint CR_L[] = {
 	0x111dc, 0x111dc,
 	0x11200, 0x11211,
 	0x11213, 0x1122b,
+	0x1123f, 0x11240,
 	0x11280, 0x11286,
 	0x11288, 0x11288,
 	0x1128a, 0x1128d,
@@ -8229,11 +8324,15 @@ static const OnigCodePoint CR_L[] = {
 	0x11d6a, 0x11d89,
 	0x11d98, 0x11d98,
 	0x11ee0, 0x11ef2,
+	0x11f02, 0x11f02,
+	0x11f04, 0x11f10,
+	0x11f12, 0x11f33,
 	0x11fb0, 0x11fb0,
 	0x12000, 0x12399,
 	0x12480, 0x12543,
 	0x12f90, 0x12ff0,
-	0x13000, 0x1342e,
+	0x13000, 0x1342f,
+	0x13441, 0x13446,
 	0x14400, 0x14646,
 	0x16800, 0x16a38,
 	0x16a40, 0x16a5e,
@@ -8256,7 +8355,9 @@ static const OnigCodePoint CR_L[] = {
 	0x1aff5, 0x1affb,
 	0x1affd, 0x1affe,
 	0x1b000, 0x1b122,
+	0x1b132, 0x1b132,
 	0x1b150, 0x1b152,
+	0x1b155, 0x1b155,
 	0x1b164, 0x1b167,
 	0x1b170, 0x1b2fb,
 	0x1bc00, 0x1bc6a,
@@ -8294,11 +8395,14 @@ static const OnigCodePoint CR_L[] = {
 	0x1d7aa, 0x1d7c2,
 	0x1d7c4, 0x1d7cb,
 	0x1df00, 0x1df1e,
+	0x1df25, 0x1df2a,
+	0x1e030, 0x1e06d,
 	0x1e100, 0x1e12c,
 	0x1e137, 0x1e13d,
 	0x1e14e, 0x1e14e,
 	0x1e290, 0x1e2ad,
 	0x1e2c0, 0x1e2eb,
+	0x1e4d0, 0x1e4eb,
 	0x1e7e0, 0x1e7e6,
 	0x1e7e8, 0x1e7eb,
 	0x1e7ed, 0x1e7ee,
@@ -8340,17 +8444,18 @@ static const OnigCodePoint CR_L[] = {
 	0x1eea5, 0x1eea9,
 	0x1eeab, 0x1eebb,
 	0x20000, 0x2a6df,
-	0x2a700, 0x2b738,
+	0x2a700, 0x2b739,
 	0x2b740, 0x2b81d,
 	0x2b820, 0x2cea1,
 	0x2ceb0, 0x2ebe0,
 	0x2f800, 0x2fa1d,
 	0x30000, 0x3134a,
+	0x31350, 0x323af,
 }; /* CR_L */
 
 /* 'LC': General Category */
 static const OnigCodePoint CR_LC[] = {
-	142,
+	143,
 	0x0041, 0x005a,
 	0x0061, 0x007a,
 	0x00b5, 0x00b5,
@@ -8492,12 +8597,13 @@ static const OnigCodePoint CR_LC[] = {
 	0x1d7c4, 0x1d7cb,
 	0x1df00, 0x1df09,
 	0x1df0b, 0x1df1e,
+	0x1df25, 0x1df2a,
 	0x1e900, 0x1e943,
 }; /* CR_LC */
 
 /* 'Ll': General Category */
 static const OnigCodePoint CR_Ll[] = {
-	657,
+	658,
 	0x0061, 0x007a,
 	0x00b5, 0x00b5,
 	0x00df, 0x00f6,
@@ -9154,12 +9260,13 @@ static const OnigCodePoint CR_Ll[] = {
 	0x1d7cb, 0x1d7cb,
 	0x1df00, 0x1df09,
 	0x1df0b, 0x1df1e,
+	0x1df25, 0x1df2a,
 	0x1e922, 0x1e943,
 }; /* CR_Ll */
 
 /* 'Lm': General Category */
 static const OnigCodePoint CR_Lm[] = {
-	69,
+	71,
 	0x02b0, 0x02c1,
 	0x02c6, 0x02d1,
 	0x02e0, 0x02e4,
@@ -9227,13 +9334,15 @@ static const OnigCodePoint CR_Lm[] = {
 	0x1aff0, 0x1aff3,
 	0x1aff5, 0x1affb,
 	0x1affd, 0x1affe,
+	0x1e030, 0x1e06d,
 	0x1e137, 0x1e13d,
+	0x1e4eb, 0x1e4eb,
 	0x1e94b, 0x1e94b,
 }; /* CR_Lm */
 
 /* 'Lo': General Category */
 static const OnigCodePoint CR_Lo[] = {
-	501,
+	510,
 	0x00aa, 0x00aa,
 	0x00ba, 0x00ba,
 	0x01bb, 0x01bb,
@@ -9598,6 +9707,7 @@ static const OnigCodePoint CR_Lo[] = {
 	0x111dc, 0x111dc,
 	0x11200, 0x11211,
 	0x11213, 0x1122b,
+	0x1123f, 0x11240,
 	0x11280, 0x11286,
 	0x11288, 0x11288,
 	0x1128a, 0x1128d,
@@ -9659,11 +9769,15 @@ static const OnigCodePoint CR_Lo[] = {
 	0x11d6a, 0x11d89,
 	0x11d98, 0x11d98,
 	0x11ee0, 0x11ef2,
+	0x11f02, 0x11f02,
+	0x11f04, 0x11f10,
+	0x11f12, 0x11f33,
 	0x11fb0, 0x11fb0,
 	0x12000, 0x12399,
 	0x12480, 0x12543,
 	0x12f90, 0x12ff0,
-	0x13000, 0x1342e,
+	0x13000, 0x1342f,
+	0x13441, 0x13446,
 	0x14400, 0x14646,
 	0x16800, 0x16a38,
 	0x16a40, 0x16a5e,
@@ -9678,7 +9792,9 @@ static const OnigCodePoint CR_Lo[] = {
 	0x18800, 0x18cd5,
 	0x18d00, 0x18d08,
 	0x1b000, 0x1b122,
+	0x1b132, 0x1b132,
 	0x1b150, 0x1b152,
+	0x1b155, 0x1b155,
 	0x1b164, 0x1b167,
 	0x1b170, 0x1b2fb,
 	0x1bc00, 0x1bc6a,
@@ -9690,6 +9806,7 @@ static const OnigCodePoint CR_Lo[] = {
 	0x1e14e, 0x1e14e,
 	0x1e290, 0x1e2ad,
 	0x1e2c0, 0x1e2eb,
+	0x1e4d0, 0x1e4ea,
 	0x1e7e0, 0x1e7e6,
 	0x1e7e8, 0x1e7eb,
 	0x1e7ed, 0x1e7ee,
@@ -9729,12 +9846,13 @@ static const OnigCodePoint CR_Lo[] = {
 	0x1eea5, 0x1eea9,
 	0x1eeab, 0x1eebb,
 	0x20000, 0x2a6df,
-	0x2a700, 0x2b738,
+	0x2a700, 0x2b739,
 	0x2b740, 0x2b81d,
 	0x2b820, 0x2cea1,
 	0x2ceb0, 0x2ebe0,
 	0x2f800, 0x2fa1d,
 	0x30000, 0x3134a,
+	0x31350, 0x323af,
 }; /* CR_Lo */
 
 /* 'Lt': General Category */
@@ -10405,7 +10523,7 @@ static const OnigCodePoint CR_Lu[] = {
 
 /* 'M': Major Category */
 static const OnigCodePoint CR_M[] = {
-	299,
+	310,
 	0x0300, 0x036f,
 	0x0483, 0x0489,
 	0x0591, 0x05bd,
@@ -10486,6 +10604,7 @@ static const OnigCodePoint CR_M[] = {
 	0x0cca, 0x0ccd,
 	0x0cd5, 0x0cd6,
 	0x0ce2, 0x0ce3,
+	0x0cf3, 0x0cf3,
 	0x0d00, 0x0d03,
 	0x0d3b, 0x0d3c,
 	0x0d3e, 0x0d44,
@@ -10504,7 +10623,7 @@ static const OnigCodePoint CR_M[] = {
 	0x0e47, 0x0e4e,
 	0x0eb1, 0x0eb1,
 	0x0eb4, 0x0ebc,
-	0x0ec8, 0x0ecd,
+	0x0ec8, 0x0ece,
 	0x0f18, 0x0f19,
 	0x0f35, 0x0f35,
 	0x0f37, 0x0f37,
@@ -10606,6 +10725,7 @@ static const OnigCodePoint CR_M[] = {
 	0x10ae5, 0x10ae6,
 	0x10d24, 0x10d27,
 	0x10eab, 0x10eac,
+	0x10efd, 0x10eff,
 	0x10f46, 0x10f50,
 	0x10f82, 0x10f85,
 	0x11000, 0x11002,
@@ -10625,6 +10745,7 @@ static const OnigCodePoint CR_M[] = {
 	0x111ce, 0x111cf,
 	0x1122c, 0x11237,
 	0x1123e, 0x1123e,
+	0x11241, 0x11241,
 	0x112df, 0x112ea,
 	0x11300, 0x11303,
 	0x1133b, 0x1133c,
@@ -10672,6 +10793,12 @@ static const OnigCodePoint CR_M[] = {
 	0x11d90, 0x11d91,
 	0x11d93, 0x11d97,
 	0x11ef3, 0x11ef6,
+	0x11f00, 0x11f01,
+	0x11f03, 0x11f03,
+	0x11f34, 0x11f3a,
+	0x11f3e, 0x11f42,
+	0x13440, 0x13440,
+	0x13447, 0x13455,
 	0x16af0, 0x16af4,
 	0x16b30, 0x16b36,
 	0x16f4f, 0x16f4f,
@@ -10699,9 +10826,11 @@ static const OnigCodePoint CR_M[] = {
 	0x1e01b, 0x1e021,
 	0x1e023, 0x1e024,
 	0x1e026, 0x1e02a,
+	0x1e08f, 0x1e08f,
 	0x1e130, 0x1e136,
 	0x1e2ae, 0x1e2ae,
 	0x1e2ec, 0x1e2ef,
+	0x1e4ec, 0x1e4ef,
 	0x1e8d0, 0x1e8d6,
 	0x1e944, 0x1e94a,
 	0xe0100, 0xe01ef,
@@ -10709,7 +10838,7 @@ static const OnigCodePoint CR_M[] = {
 
 /* 'Mc': General Category */
 static const OnigCodePoint CR_Mc[] = {
-	177,
+	182,
 	0x0903, 0x0903,
 	0x093b, 0x093b,
 	0x093e, 0x0940,
@@ -10745,6 +10874,7 @@ static const OnigCodePoint CR_Mc[] = {
 	0x0cc7, 0x0cc8,
 	0x0cca, 0x0ccb,
 	0x0cd5, 0x0cd6,
+	0x0cf3, 0x0cf3,
 	0x0d02, 0x0d03,
 	0x0d3e, 0x0d40,
 	0x0d46, 0x0d48,
@@ -10883,6 +11013,10 @@ static const OnigCodePoint CR_Mc[] = {
 	0x11d93, 0x11d94,
 	0x11d96, 0x11d96,
 	0x11ef5, 0x11ef6,
+	0x11f03, 0x11f03,
+	0x11f34, 0x11f35,
+	0x11f3e, 0x11f3f,
+	0x11f41, 0x11f41,
 	0x16f51, 0x16f87,
 	0x16ff0, 0x16ff1,
 	0x1d165, 0x1d166,
@@ -10901,7 +11035,7 @@ static const OnigCodePoint CR_Me[] = {
 
 /* 'Mn': General Category */
 static const OnigCodePoint CR_Mn[] = {
-	336,
+	346,
 	0x0300, 0x036f,
 	0x0483, 0x0487,
 	0x0591, 0x05bd,
@@ -10994,7 +11128,7 @@ static const OnigCodePoint CR_Mn[] = {
 	0x0e47, 0x0e4e,
 	0x0eb1, 0x0eb1,
 	0x0eb4, 0x0ebc,
-	0x0ec8, 0x0ecd,
+	0x0ec8, 0x0ece,
 	0x0f18, 0x0f19,
 	0x0f35, 0x0f35,
 	0x0f37, 0x0f37,
@@ -11125,6 +11259,7 @@ static const OnigCodePoint CR_Mn[] = {
 	0x10ae5, 0x10ae6,
 	0x10d24, 0x10d27,
 	0x10eab, 0x10eac,
+	0x10efd, 0x10eff,
 	0x10f46, 0x10f50,
 	0x10f82, 0x10f85,
 	0x11001, 0x11001,
@@ -11147,6 +11282,7 @@ static const OnigCodePoint CR_Mn[] = {
 	0x11234, 0x11234,
 	0x11236, 0x11237,
 	0x1123e, 0x1123e,
+	0x11241, 0x11241,
 	0x112df, 0x112df,
 	0x112e3, 0x112ea,
 	0x11300, 0x11301,
@@ -11208,6 +11344,12 @@ static const OnigCodePoint CR_Mn[] = {
 	0x11d95, 0x11d95,
 	0x11d97, 0x11d97,
 	0x11ef3, 0x11ef4,
+	0x11f00, 0x11f01,
+	0x11f36, 0x11f3a,
+	0x11f40, 0x11f40,
+	0x11f42, 0x11f42,
+	0x13440, 0x13440,
+	0x13447, 0x13455,
 	0x16af0, 0x16af4,
 	0x16b30, 0x16b36,
 	0x16f4f, 0x16f4f,
@@ -11232,9 +11374,11 @@ static const OnigCodePoint CR_Mn[] = {
 	0x1e01b, 0x1e021,
 	0x1e023, 0x1e024,
 	0x1e026, 0x1e02a,
+	0x1e08f, 0x1e08f,
 	0x1e130, 0x1e136,
 	0x1e2ae, 0x1e2ae,
 	0x1e2ec, 0x1e2ef,
+	0x1e4ec, 0x1e4ef,
 	0x1e8d0, 0x1e8d6,
 	0x1e944, 0x1e94a,
 	0xe0100, 0xe01ef,
@@ -11242,7 +11386,7 @@ static const OnigCodePoint CR_Mn[] = {
 
 /* 'N': Major Category */
 static const OnigCodePoint CR_N[] = {
-	134,
+	137,
 	0x0030, 0x0039,
 	0x00b2, 0x00b3,
 	0x00b9, 0x00b9,
@@ -11356,6 +11500,7 @@ static const OnigCodePoint CR_N[] = {
 	0x11c50, 0x11c6c,
 	0x11d50, 0x11d59,
 	0x11da0, 0x11da9,
+	0x11f50, 0x11f59,
 	0x11fc0, 0x11fd4,
 	0x12400, 0x1246e,
 	0x16a60, 0x16a69,
@@ -11363,11 +11508,13 @@ static const OnigCodePoint CR_N[] = {
 	0x16b50, 0x16b59,
 	0x16b5b, 0x16b61,
 	0x16e80, 0x16e96,
+	0x1d2c0, 0x1d2d3,
 	0x1d2e0, 0x1d2f3,
 	0x1d360, 0x1d378,
 	0x1d7ce, 0x1d7ff,
 	0x1e140, 0x1e149,
 	0x1e2f0, 0x1e2f9,
+	0x1e4f0, 0x1e4f9,
 	0x1e8c7, 0x1e8cf,
 	0x1e950, 0x1e959,
 	0x1ec71, 0x1ecab,
@@ -11401,7 +11548,7 @@ static const OnigCodePoint CR_Nl[] = {
 
 /* 'No': General Category */
 static const OnigCodePoint CR_No[] = {
-	71,
+	72,
 	0x00b2, 0x00b3,
 	0x00b9, 0x00b9,
 	0x00bc, 0x00be,
@@ -11464,6 +11611,7 @@ static const OnigCodePoint CR_No[] = {
 	0x11fc0, 0x11fd4,
 	0x16b5b, 0x16b61,
 	0x16e80, 0x16e96,
+	0x1d2c0, 0x1d2d3,
 	0x1d2e0, 0x1d2f3,
 	0x1d360, 0x1d378,
 	0x1e8c7, 0x1e8cf,
@@ -11627,7 +11775,7 @@ static const OnigCodePoint CR_Pi[] = {
 
 /* 'Po': General Category */
 static const OnigCodePoint CR_Po[] = {
-	185,
+	187,
 	0x0021, 0x0023,
 	0x0025, 0x0027,
 	0x002a, 0x002a,
@@ -11798,9 +11946,11 @@ static const OnigCodePoint CR_Po[] = {
 	0x11a3f, 0x11a46,
 	0x11a9a, 0x11a9c,
 	0x11a9e, 0x11aa2,
+	0x11b00, 0x11b09,
 	0x11c41, 0x11c45,
 	0x11c70, 0x11c71,
 	0x11ef7, 0x11ef8,
+	0x11f43, 0x11f4f,
 	0x11fff, 0x11fff,
 	0x12470, 0x12474,
 	0x12ff1, 0x12ff2,
@@ -11901,7 +12051,7 @@ static const OnigCodePoint CR_Ps[] = {
 
 /* 'S': Major Category */
 static const OnigCodePoint CR_S[] = {
-	234,
+	232,
 	0x0024, 0x0024,
 	0x002b, 0x002b,
 	0x003c, 0x003e,
@@ -12111,10 +12261,10 @@ static const OnigCodePoint CR_S[] = {
 	0x1f250, 0x1f251,
 	0x1f260, 0x1f265,
 	0x1f300, 0x1f6d7,
-	0x1f6dd, 0x1f6ec,
+	0x1f6dc, 0x1f6ec,
 	0x1f6f0, 0x1f6fc,
-	0x1f700, 0x1f773,
-	0x1f780, 0x1f7d8,
+	0x1f700, 0x1f776,
+	0x1f77b, 0x1f7d9,
 	0x1f7e0, 0x1f7eb,
 	0x1f7f0, 0x1f7f0,
 	0x1f800, 0x1f80b,
@@ -12125,15 +12275,13 @@ static const OnigCodePoint CR_S[] = {
 	0x1f8b0, 0x1f8b1,
 	0x1f900, 0x1fa53,
 	0x1fa60, 0x1fa6d,
-	0x1fa70, 0x1fa74,
-	0x1fa78, 0x1fa7c,
-	0x1fa80, 0x1fa86,
-	0x1fa90, 0x1faac,
-	0x1fab0, 0x1faba,
-	0x1fac0, 0x1fac5,
-	0x1fad0, 0x1fad9,
-	0x1fae0, 0x1fae7,
-	0x1faf0, 0x1faf6,
+	0x1fa70, 0x1fa7c,
+	0x1fa80, 0x1fa88,
+	0x1fa90, 0x1fabd,
+	0x1fabf, 0x1fac5,
+	0x1face, 0x1fadb,
+	0x1fae0, 0x1fae8,
+	0x1faf0, 0x1faf8,
 	0x1fb00, 0x1fb92,
 	0x1fb94, 0x1fbca,
 }; /* CR_S */
@@ -12271,7 +12419,7 @@ static const OnigCodePoint CR_Sm[] = {
 
 /* 'So': General Category */
 static const OnigCodePoint CR_So[] = {
-	186,
+	184,
 	0x00a6, 0x00a6,
 	0x00a9, 0x00a9,
 	0x00ae, 0x00ae,
@@ -12433,10 +12581,10 @@ static const OnigCodePoint CR_So[] = {
 	0x1f260, 0x1f265,
 	0x1f300, 0x1f3fa,
 	0x1f400, 0x1f6d7,
-	0x1f6dd, 0x1f6ec,
+	0x1f6dc, 0x1f6ec,
 	0x1f6f0, 0x1f6fc,
-	0x1f700, 0x1f773,
-	0x1f780, 0x1f7d8,
+	0x1f700, 0x1f776,
+	0x1f77b, 0x1f7d9,
 	0x1f7e0, 0x1f7eb,
 	0x1f7f0, 0x1f7f0,
 	0x1f800, 0x1f80b,
@@ -12447,15 +12595,13 @@ static const OnigCodePoint CR_So[] = {
 	0x1f8b0, 0x1f8b1,
 	0x1f900, 0x1fa53,
 	0x1fa60, 0x1fa6d,
-	0x1fa70, 0x1fa74,
-	0x1fa78, 0x1fa7c,
-	0x1fa80, 0x1fa86,
-	0x1fa90, 0x1faac,
-	0x1fab0, 0x1faba,
-	0x1fac0, 0x1fac5,
-	0x1fad0, 0x1fad9,
-	0x1fae0, 0x1fae7,
-	0x1faf0, 0x1faf6,
+	0x1fa70, 0x1fa7c,
+	0x1fa80, 0x1fa88,
+	0x1fa90, 0x1fabd,
+	0x1fabf, 0x1fac5,
+	0x1face, 0x1fadb,
+	0x1fae0, 0x1fae8,
+	0x1faf0, 0x1faf8,
 	0x1fb00, 0x1fb92,
 	0x1fb94, 0x1fbca,
 }; /* CR_So */
@@ -12651,7 +12797,7 @@ static const OnigCodePoint CR_Math[] = {
 
 /* 'Cased': Derived Property */
 static const OnigCodePoint CR_Cased[] = {
-	151,
+	157,
 	0x0041, 0x005a,
 	0x0061, 0x007a,
 	0x00aa, 0x00aa,
@@ -12683,7 +12829,7 @@ static const OnigCodePoint CR_Cased[] = {
 	0x10c7, 0x10c7,
 	0x10cd, 0x10cd,
 	0x10d0, 0x10fa,
-	0x10fd, 0x10ff,
+	0x10fc, 0x10ff,
 	0x13a0, 0x13f5,
 	0x13f8, 0x13fd,
 	0x1c80, 0x1c88,
@@ -12743,10 +12889,10 @@ static const OnigCodePoint CR_Cased[] = {
 	0xa7d0, 0xa7d1,
 	0xa7d3, 0xa7d3,
 	0xa7d5, 0xa7d9,
-	0xa7f5, 0xa7f6,
+	0xa7f2, 0xa7f6,
 	0xa7f8, 0xa7fa,
 	0xab30, 0xab5a,
-	0xab5c, 0xab68,
+	0xab5c, 0xab69,
 	0xab70, 0xabbf,
 	0xfb00, 0xfb06,
 	0xfb13, 0xfb17,
@@ -12763,6 +12909,10 @@ static const OnigCodePoint CR_Cased[] = {
 	0x105a3, 0x105b1,
 	0x105b3, 0x105b9,
 	0x105bb, 0x105bc,
+	0x10780, 0x10780,
+	0x10783, 0x10785,
+	0x10787, 0x107b0,
+	0x107b2, 0x107ba,
 	0x10c80, 0x10cb2,
 	0x10cc0, 0x10cf2,
 	0x118a0, 0x118df,
@@ -12799,6 +12949,8 @@ static const OnigCodePoint CR_Cased[] = {
 	0x1d7c4, 0x1d7cb,
 	0x1df00, 0x1df09,
 	0x1df0b, 0x1df1e,
+	0x1df25, 0x1df2a,
+	0x1e030, 0x1e06d,
 	0x1e900, 0x1e943,
 	0x1f130, 0x1f149,
 	0x1f150, 0x1f169,
@@ -12807,7 +12959,7 @@ static const OnigCodePoint CR_Cased[] = {
 
 /* 'Case_Ignorable': Derived Property */
 static const OnigCodePoint CR_Case_Ignorable[] = {
-	427,
+	437,
 	0x0027, 0x0027,
 	0x002e, 0x002e,
 	0x003a, 0x003a,
@@ -12921,7 +13073,7 @@ static const OnigCodePoint CR_Case_Ignorable[] = {
 	0x0eb1, 0x0eb1,
 	0x0eb4, 0x0ebc,
 	0x0ec6, 0x0ec6,
-	0x0ec8, 0x0ecd,
+	0x0ec8, 0x0ece,
 	0x0f18, 0x0f19,
 	0x0f35, 0x0f35,
 	0x0f37, 0x0f37,
@@ -13110,6 +13262,7 @@ static const OnigCodePoint CR_Case_Ignorable[] = {
 	0x10ae5, 0x10ae6,
 	0x10d24, 0x10d27,
 	0x10eab, 0x10eac,
+	0x10efd, 0x10eff,
 	0x10f46, 0x10f50,
 	0x10f82, 0x10f85,
 	0x11001, 0x11001,
@@ -13134,6 +13287,7 @@ static const OnigCodePoint CR_Case_Ignorable[] = {
 	0x11234, 0x11234,
 	0x11236, 0x11237,
 	0x1123e, 0x1123e,
+	0x11241, 0x11241,
 	0x112df, 0x112df,
 	0x112e3, 0x112ea,
 	0x11300, 0x11301,
@@ -13195,7 +13349,12 @@ static const OnigCodePoint CR_Case_Ignorable[] = {
 	0x11d95, 0x11d95,
 	0x11d97, 0x11d97,
 	0x11ef3, 0x11ef4,
-	0x13430, 0x13438,
+	0x11f00, 0x11f01,
+	0x11f36, 0x11f3a,
+	0x11f40, 0x11f40,
+	0x11f42, 0x11f42,
+	0x13430, 0x13440,
+	0x13447, 0x13455,
 	0x16af0, 0x16af4,
 	0x16b30, 0x16b36,
 	0x16b40, 0x16b43,
@@ -13226,9 +13385,12 @@ static const OnigCodePoint CR_Case_Ignorable[] = {
 	0x1e01b, 0x1e021,
 	0x1e023, 0x1e024,
 	0x1e026, 0x1e02a,
+	0x1e030, 0x1e06d,
+	0x1e08f, 0x1e08f,
 	0x1e130, 0x1e13d,
 	0x1e2ae, 0x1e2ae,
 	0x1e2ec, 0x1e2ef,
+	0x1e4eb, 0x1e4ef,
 	0x1e8d0, 0x1e8d6,
 	0x1e944, 0x1e94b,
 	0x1f3fb, 0x1f3ff,
@@ -15879,7 +16041,7 @@ static const OnigCodePoint CR_Changes_When_Casemapped[] = {
 
 /* 'ID_Start': Derived Property */
 static const OnigCodePoint CR_ID_Start[] = {
-	648,
+	659,
 	0x0041, 0x005a,
 	0x0061, 0x007a,
 	0x00aa, 0x00aa,
@@ -16348,6 +16510,7 @@ static const OnigCodePoint CR_ID_Start[] = {
 	0x111dc, 0x111dc,
 	0x11200, 0x11211,
 	0x11213, 0x1122b,
+	0x1123f, 0x11240,
 	0x11280, 0x11286,
 	0x11288, 0x11288,
 	0x1128a, 0x1128d,
@@ -16410,12 +16573,16 @@ static const OnigCodePoint CR_ID_Start[] = {
 	0x11d6a, 0x11d89,
 	0x11d98, 0x11d98,
 	0x11ee0, 0x11ef2,
+	0x11f02, 0x11f02,
+	0x11f04, 0x11f10,
+	0x11f12, 0x11f33,
 	0x11fb0, 0x11fb0,
 	0x12000, 0x12399,
 	0x12400, 0x1246e,
 	0x12480, 0x12543,
 	0x12f90, 0x12ff0,
-	0x13000, 0x1342e,
+	0x13000, 0x1342f,
+	0x13441, 0x13446,
 	0x14400, 0x14646,
 	0x16800, 0x16a38,
 	0x16a40, 0x16a5e,
@@ -16438,7 +16605,9 @@ static const OnigCodePoint CR_ID_Start[] = {
 	0x1aff5, 0x1affb,
 	0x1affd, 0x1affe,
 	0x1b000, 0x1b122,
+	0x1b132, 0x1b132,
 	0x1b150, 0x1b152,
+	0x1b155, 0x1b155,
 	0x1b164, 0x1b167,
 	0x1b170, 0x1b2fb,
 	0x1bc00, 0x1bc6a,
@@ -16476,11 +16645,14 @@ static const OnigCodePoint CR_ID_Start[] = {
 	0x1d7aa, 0x1d7c2,
 	0x1d7c4, 0x1d7cb,
 	0x1df00, 0x1df1e,
+	0x1df25, 0x1df2a,
+	0x1e030, 0x1e06d,
 	0x1e100, 0x1e12c,
 	0x1e137, 0x1e13d,
 	0x1e14e, 0x1e14e,
 	0x1e290, 0x1e2ad,
 	0x1e2c0, 0x1e2eb,
+	0x1e4d0, 0x1e4eb,
 	0x1e7e0, 0x1e7e6,
 	0x1e7e8, 0x1e7eb,
 	0x1e7ed, 0x1e7ee,
@@ -16522,17 +16694,18 @@ static const OnigCodePoint CR_ID_Start[] = {
 	0x1eea5, 0x1eea9,
 	0x1eeab, 0x1eebb,
 	0x20000, 0x2a6df,
-	0x2a700, 0x2b738,
+	0x2a700, 0x2b739,
 	0x2b740, 0x2b81d,
 	0x2b820, 0x2cea1,
 	0x2ceb0, 0x2ebe0,
 	0x2f800, 0x2fa1d,
 	0x30000, 0x3134a,
+	0x31350, 0x323af,
 }; /* CR_ID_Start */
 
 /* 'ID_Continue': Derived Property */
 static const OnigCodePoint CR_ID_Continue[] = {
-	756,
+	768,
 	0x0030, 0x0039,
 	0x0041, 0x005a,
 	0x005f, 0x005f,
@@ -16691,7 +16864,7 @@ static const OnigCodePoint CR_ID_Continue[] = {
 	0x0cdd, 0x0cde,
 	0x0ce0, 0x0ce3,
 	0x0ce6, 0x0cef,
-	0x0cf1, 0x0cf2,
+	0x0cf1, 0x0cf3,
 	0x0d00, 0x0d0c,
 	0x0d0e, 0x0d10,
 	0x0d12, 0x0d44,
@@ -16724,7 +16897,7 @@ static const OnigCodePoint CR_ID_Continue[] = {
 	0x0ea7, 0x0ebd,
 	0x0ec0, 0x0ec4,
 	0x0ec6, 0x0ec6,
-	0x0ec8, 0x0ecd,
+	0x0ec8, 0x0ece,
 	0x0ed0, 0x0ed9,
 	0x0edc, 0x0edf,
 	0x0f00, 0x0f00,
@@ -17037,7 +17210,7 @@ static const OnigCodePoint CR_ID_Continue[] = {
 	0x10e80, 0x10ea9,
 	0x10eab, 0x10eac,
 	0x10eb0, 0x10eb1,
-	0x10f00, 0x10f1c,
+	0x10efd, 0x10f1c,
 	0x10f27, 0x10f27,
 	0x10f30, 0x10f50,
 	0x10f70, 0x10f85,
@@ -17060,7 +17233,7 @@ static const OnigCodePoint CR_ID_Continue[] = {
 	0x111dc, 0x111dc,
 	0x11200, 0x11211,
 	0x11213, 0x11237,
-	0x1123e, 0x1123e,
+	0x1123e, 0x11241,
 	0x11280, 0x11286,
 	0x11288, 0x11288,
 	0x1128a, 0x1128d,
@@ -17141,12 +17314,17 @@ static const OnigCodePoint CR_ID_Continue[] = {
 	0x11d93, 0x11d98,
 	0x11da0, 0x11da9,
 	0x11ee0, 0x11ef6,
+	0x11f00, 0x11f10,
+	0x11f12, 0x11f3a,
+	0x11f3e, 0x11f42,
+	0x11f50, 0x11f59,
 	0x11fb0, 0x11fb0,
 	0x12000, 0x12399,
 	0x12400, 0x1246e,
 	0x12480, 0x12543,
 	0x12f90, 0x12ff0,
-	0x13000, 0x1342e,
+	0x13000, 0x1342f,
+	0x13440, 0x13455,
 	0x14400, 0x14646,
 	0x16800, 0x16a38,
 	0x16a40, 0x16a5e,
@@ -17174,7 +17352,9 @@ static const OnigCodePoint CR_ID_Continue[] = {
 	0x1aff5, 0x1affb,
 	0x1affd, 0x1affe,
 	0x1b000, 0x1b122,
+	0x1b132, 0x1b132,
 	0x1b150, 0x1b152,
+	0x1b155, 0x1b155,
 	0x1b164, 0x1b167,
 	0x1b170, 0x1b2fb,
 	0x1bc00, 0x1bc6a,
@@ -17228,17 +17408,21 @@ static const OnigCodePoint CR_ID_Continue[] = {
 	0x1da9b, 0x1da9f,
 	0x1daa1, 0x1daaf,
 	0x1df00, 0x1df1e,
+	0x1df25, 0x1df2a,
 	0x1e000, 0x1e006,
 	0x1e008, 0x1e018,
 	0x1e01b, 0x1e021,
 	0x1e023, 0x1e024,
 	0x1e026, 0x1e02a,
+	0x1e030, 0x1e06d,
+	0x1e08f, 0x1e08f,
 	0x1e100, 0x1e12c,
 	0x1e130, 0x1e13d,
 	0x1e140, 0x1e149,
 	0x1e14e, 0x1e14e,
 	0x1e290, 0x1e2ae,
 	0x1e2c0, 0x1e2f9,
+	0x1e4d0, 0x1e4f9,
 	0x1e7e0, 0x1e7e6,
 	0x1e7e8, 0x1e7eb,
 	0x1e7ed, 0x1e7ee,
@@ -17282,18 +17466,19 @@ static const OnigCodePoint CR_ID_Continue[] = {
 	0x1eeab, 0x1eebb,
 	0x1fbf0, 0x1fbf9,
 	0x20000, 0x2a6df,
-	0x2a700, 0x2b738,
+	0x2a700, 0x2b739,
 	0x2b740, 0x2b81d,
 	0x2b820, 0x2cea1,
 	0x2ceb0, 0x2ebe0,
 	0x2f800, 0x2fa1d,
 	0x30000, 0x3134a,
+	0x31350, 0x323af,
 	0xe0100, 0xe01ef,
 }; /* CR_ID_Continue */
 
 /* 'XID_Start': Derived Property */
 static const OnigCodePoint CR_XID_Start[] = {
-	655,
+	666,
 	0x0041, 0x005a,
 	0x0061, 0x007a,
 	0x00aa, 0x00aa,
@@ -17769,6 +17954,7 @@ static const OnigCodePoint CR_XID_Start[] = {
 	0x111dc, 0x111dc,
 	0x11200, 0x11211,
 	0x11213, 0x1122b,
+	0x1123f, 0x11240,
 	0x11280, 0x11286,
 	0x11288, 0x11288,
 	0x1128a, 0x1128d,
@@ -17831,12 +18017,16 @@ static const OnigCodePoint CR_XID_Start[] = {
 	0x11d6a, 0x11d89,
 	0x11d98, 0x11d98,
 	0x11ee0, 0x11ef2,
+	0x11f02, 0x11f02,
+	0x11f04, 0x11f10,
+	0x11f12, 0x11f33,
 	0x11fb0, 0x11fb0,
 	0x12000, 0x12399,
 	0x12400, 0x1246e,
 	0x12480, 0x12543,
 	0x12f90, 0x12ff0,
-	0x13000, 0x1342e,
+	0x13000, 0x1342f,
+	0x13441, 0x13446,
 	0x14400, 0x14646,
 	0x16800, 0x16a38,
 	0x16a40, 0x16a5e,
@@ -17859,7 +18049,9 @@ static const OnigCodePoint CR_XID_Start[] = {
 	0x1aff5, 0x1affb,
 	0x1affd, 0x1affe,
 	0x1b000, 0x1b122,
+	0x1b132, 0x1b132,
 	0x1b150, 0x1b152,
+	0x1b155, 0x1b155,
 	0x1b164, 0x1b167,
 	0x1b170, 0x1b2fb,
 	0x1bc00, 0x1bc6a,
@@ -17897,11 +18089,14 @@ static const OnigCodePoint CR_XID_Start[] = {
 	0x1d7aa, 0x1d7c2,
 	0x1d7c4, 0x1d7cb,
 	0x1df00, 0x1df1e,
+	0x1df25, 0x1df2a,
+	0x1e030, 0x1e06d,
 	0x1e100, 0x1e12c,
 	0x1e137, 0x1e13d,
 	0x1e14e, 0x1e14e,
 	0x1e290, 0x1e2ad,
 	0x1e2c0, 0x1e2eb,
+	0x1e4d0, 0x1e4eb,
 	0x1e7e0, 0x1e7e6,
 	0x1e7e8, 0x1e7eb,
 	0x1e7ed, 0x1e7ee,
@@ -17943,17 +18138,18 @@ static const OnigCodePoint CR_XID_Start[] = {
 	0x1eea5, 0x1eea9,
 	0x1eeab, 0x1eebb,
 	0x20000, 0x2a6df,
-	0x2a700, 0x2b738,
+	0x2a700, 0x2b739,
 	0x2b740, 0x2b81d,
 	0x2b820, 0x2cea1,
 	0x2ceb0, 0x2ebe0,
 	0x2f800, 0x2fa1d,
 	0x30000, 0x3134a,
+	0x31350, 0x323af,
 }; /* CR_XID_Start */
 
 /* 'XID_Continue': Derived Property */
 static const OnigCodePoint CR_XID_Continue[] = {
-	763,
+	775,
 	0x0030, 0x0039,
 	0x0041, 0x005a,
 	0x005f, 0x005f,
@@ -18112,7 +18308,7 @@ static const OnigCodePoint CR_XID_Continue[] = {
 	0x0cdd, 0x0cde,
 	0x0ce0, 0x0ce3,
 	0x0ce6, 0x0cef,
-	0x0cf1, 0x0cf2,
+	0x0cf1, 0x0cf3,
 	0x0d00, 0x0d0c,
 	0x0d0e, 0x0d10,
 	0x0d12, 0x0d44,
@@ -18145,7 +18341,7 @@ static const OnigCodePoint CR_XID_Continue[] = {
 	0x0ea7, 0x0ebd,
 	0x0ec0, 0x0ec4,
 	0x0ec6, 0x0ec6,
-	0x0ec8, 0x0ecd,
+	0x0ec8, 0x0ece,
 	0x0ed0, 0x0ed9,
 	0x0edc, 0x0edf,
 	0x0f00, 0x0f00,
@@ -18465,7 +18661,7 @@ static const OnigCodePoint CR_XID_Continue[] = {
 	0x10e80, 0x10ea9,
 	0x10eab, 0x10eac,
 	0x10eb0, 0x10eb1,
-	0x10f00, 0x10f1c,
+	0x10efd, 0x10f1c,
 	0x10f27, 0x10f27,
 	0x10f30, 0x10f50,
 	0x10f70, 0x10f85,
@@ -18488,7 +18684,7 @@ static const OnigCodePoint CR_XID_Continue[] = {
 	0x111dc, 0x111dc,
 	0x11200, 0x11211,
 	0x11213, 0x11237,
-	0x1123e, 0x1123e,
+	0x1123e, 0x11241,
 	0x11280, 0x11286,
 	0x11288, 0x11288,
 	0x1128a, 0x1128d,
@@ -18569,12 +18765,17 @@ static const OnigCodePoint CR_XID_Continue[] = {
 	0x11d93, 0x11d98,
 	0x11da0, 0x11da9,
 	0x11ee0, 0x11ef6,
+	0x11f00, 0x11f10,
+	0x11f12, 0x11f3a,
+	0x11f3e, 0x11f42,
+	0x11f50, 0x11f59,
 	0x11fb0, 0x11fb0,
 	0x12000, 0x12399,
 	0x12400, 0x1246e,
 	0x12480, 0x12543,
 	0x12f90, 0x12ff0,
-	0x13000, 0x1342e,
+	0x13000, 0x1342f,
+	0x13440, 0x13455,
 	0x14400, 0x14646,
 	0x16800, 0x16a38,
 	0x16a40, 0x16a5e,
@@ -18602,7 +18803,9 @@ static const OnigCodePoint CR_XID_Continue[] = {
 	0x1aff5, 0x1affb,
 	0x1affd, 0x1affe,
 	0x1b000, 0x1b122,
+	0x1b132, 0x1b132,
 	0x1b150, 0x1b152,
+	0x1b155, 0x1b155,
 	0x1b164, 0x1b167,
 	0x1b170, 0x1b2fb,
 	0x1bc00, 0x1bc6a,
@@ -18656,17 +18859,21 @@ static const OnigCodePoint CR_XID_Continue[] = {
 	0x1da9b, 0x1da9f,
 	0x1daa1, 0x1daaf,
 	0x1df00, 0x1df1e,
+	0x1df25, 0x1df2a,
 	0x1e000, 0x1e006,
 	0x1e008, 0x1e018,
 	0x1e01b, 0x1e021,
 	0x1e023, 0x1e024,
 	0x1e026, 0x1e02a,
+	0x1e030, 0x1e06d,
+	0x1e08f, 0x1e08f,
 	0x1e100, 0x1e12c,
 	0x1e130, 0x1e13d,
 	0x1e140, 0x1e149,
 	0x1e14e, 0x1e14e,
 	0x1e290, 0x1e2ae,
 	0x1e2c0, 0x1e2f9,
+	0x1e4d0, 0x1e4f9,
 	0x1e7e0, 0x1e7e6,
 	0x1e7e8, 0x1e7eb,
 	0x1e7ed, 0x1e7ee,
@@ -18710,12 +18917,13 @@ static const OnigCodePoint CR_XID_Continue[] = {
 	0x1eeab, 0x1eebb,
 	0x1fbf0, 0x1fbf9,
 	0x20000, 0x2a6df,
-	0x2a700, 0x2b738,
+	0x2a700, 0x2b739,
 	0x2b740, 0x2b81d,
 	0x2b820, 0x2cea1,
 	0x2ceb0, 0x2ebe0,
 	0x2f800, 0x2fa1d,
 	0x30000, 0x3134a,
+	0x31350, 0x323af,
 	0xe0100, 0xe01ef,
 }; /* CR_XID_Continue */
 
@@ -18743,7 +18951,7 @@ static const OnigCodePoint CR_Default_Ignorable_Code_Point[] = {
 
 /* 'Grapheme_Extend': Derived Property */
 static const OnigCodePoint CR_Grapheme_Extend[] = {
-	353,
+	363,
 	0x0300, 0x036f,
 	0x0483, 0x0489,
 	0x0591, 0x05bd,
@@ -18846,7 +19054,7 @@ static const OnigCodePoint CR_Grapheme_Extend[] = {
 	0x0e47, 0x0e4e,
 	0x0eb1, 0x0eb1,
 	0x0eb4, 0x0ebc,
-	0x0ec8, 0x0ecd,
+	0x0ec8, 0x0ece,
 	0x0f18, 0x0f19,
 	0x0f35, 0x0f35,
 	0x0f37, 0x0f37,
@@ -18975,6 +19183,7 @@ static const OnigCodePoint CR_Grapheme_Extend[] = {
 	0x10ae5, 0x10ae6,
 	0x10d24, 0x10d27,
 	0x10eab, 0x10eac,
+	0x10efd, 0x10eff,
 	0x10f46, 0x10f50,
 	0x10f82, 0x10f85,
 	0x11001, 0x11001,
@@ -18997,6 +19206,7 @@ static const OnigCodePoint CR_Grapheme_Extend[] = {
 	0x11234, 0x11234,
 	0x11236, 0x11237,
 	0x1123e, 0x1123e,
+	0x11241, 0x11241,
 	0x112df, 0x112df,
 	0x112e3, 0x112ea,
 	0x11300, 0x11301,
@@ -19064,6 +19274,12 @@ static const OnigCodePoint CR_Grapheme_Extend[] = {
 	0x11d95, 0x11d95,
 	0x11d97, 0x11d97,
 	0x11ef3, 0x11ef4,
+	0x11f00, 0x11f01,
+	0x11f36, 0x11f3a,
+	0x11f40, 0x11f40,
+	0x11f42, 0x11f42,
+	0x13440, 0x13440,
+	0x13447, 0x13455,
 	0x16af0, 0x16af4,
 	0x16b30, 0x16b36,
 	0x16f4f, 0x16f4f,
@@ -19090,9 +19306,11 @@ static const OnigCodePoint CR_Grapheme_Extend[] = {
 	0x1e01b, 0x1e021,
 	0x1e023, 0x1e024,
 	0x1e026, 0x1e02a,
+	0x1e08f, 0x1e08f,
 	0x1e130, 0x1e136,
 	0x1e2ae, 0x1e2ae,
 	0x1e2ec, 0x1e2ef,
+	0x1e4ec, 0x1e4ef,
 	0x1e8d0, 0x1e8d6,
 	0x1e944, 0x1e94a,
 	0xe0020, 0xe007f,
@@ -19101,7 +19319,7 @@ static const OnigCodePoint CR_Grapheme_Extend[] = {
 
 /* 'Grapheme_Base': Derived Property */
 static const OnigCodePoint CR_Grapheme_Base[] = {
-	861,
+	875,
 	0x0020, 0x007e,
 	0x00a0, 0x00ac,
 	0x00ae, 0x02ff,
@@ -19251,7 +19469,7 @@ static const OnigCodePoint CR_Grapheme_Base[] = {
 	0x0cdd, 0x0cde,
 	0x0ce0, 0x0ce1,
 	0x0ce6, 0x0cef,
-	0x0cf1, 0x0cf2,
+	0x0cf1, 0x0cf3,
 	0x0d02, 0x0d0c,
 	0x0d0e, 0x0d10,
 	0x0d12, 0x0d3a,
@@ -19670,6 +19888,7 @@ static const OnigCodePoint CR_Grapheme_Base[] = {
 	0x11232, 0x11233,
 	0x11235, 0x11235,
 	0x11238, 0x1123d,
+	0x1123f, 0x11240,
 	0x11280, 0x11286,
 	0x11288, 0x11288,
 	0x1128a, 0x1128d,
@@ -19756,6 +19975,7 @@ static const OnigCodePoint CR_Grapheme_Base[] = {
 	0x11a97, 0x11a97,
 	0x11a9a, 0x11aa2,
 	0x11ab0, 0x11af8,
+	0x11b00, 0x11b09,
 	0x11c00, 0x11c08,
 	0x11c0a, 0x11c2f,
 	0x11c3e, 0x11c3e,
@@ -19779,6 +19999,11 @@ static const OnigCodePoint CR_Grapheme_Base[] = {
 	0x11da0, 0x11da9,
 	0x11ee0, 0x11ef2,
 	0x11ef5, 0x11ef8,
+	0x11f02, 0x11f10,
+	0x11f12, 0x11f35,
+	0x11f3e, 0x11f3f,
+	0x11f41, 0x11f41,
+	0x11f43, 0x11f59,
 	0x11fb0, 0x11fb0,
 	0x11fc0, 0x11ff1,
 	0x11fff, 0x12399,
@@ -19786,7 +20011,8 @@ static const OnigCodePoint CR_Grapheme_Base[] = {
 	0x12470, 0x12474,
 	0x12480, 0x12543,
 	0x12f90, 0x12ff2,
-	0x13000, 0x1342e,
+	0x13000, 0x1342f,
+	0x13441, 0x13446,
 	0x14400, 0x14646,
 	0x16800, 0x16a38,
 	0x16a40, 0x16a5e,
@@ -19814,7 +20040,9 @@ static const OnigCodePoint CR_Grapheme_Base[] = {
 	0x1aff5, 0x1affb,
 	0x1affd, 0x1affe,
 	0x1b000, 0x1b122,
+	0x1b132, 0x1b132,
 	0x1b150, 0x1b152,
+	0x1b155, 0x1b155,
 	0x1b164, 0x1b167,
 	0x1b170, 0x1b2fb,
 	0x1bc00, 0x1bc6a,
@@ -19834,6 +20062,7 @@ static const OnigCodePoint CR_Grapheme_Base[] = {
 	0x1d1ae, 0x1d1ea,
 	0x1d200, 0x1d241,
 	0x1d245, 0x1d245,
+	0x1d2c0, 0x1d2d3,
 	0x1d2e0, 0x1d2f3,
 	0x1d300, 0x1d356,
 	0x1d360, 0x1d378,
@@ -19863,6 +20092,8 @@ static const OnigCodePoint CR_Grapheme_Base[] = {
 	0x1da76, 0x1da83,
 	0x1da85, 0x1da8b,
 	0x1df00, 0x1df1e,
+	0x1df25, 0x1df2a,
+	0x1e030, 0x1e06d,
 	0x1e100, 0x1e12c,
 	0x1e137, 0x1e13d,
 	0x1e140, 0x1e149,
@@ -19871,6 +20102,8 @@ static const OnigCodePoint CR_Grapheme_Base[] = {
 	0x1e2c0, 0x1e2eb,
 	0x1e2f0, 0x1e2f9,
 	0x1e2ff, 0x1e2ff,
+	0x1e4d0, 0x1e4eb,
+	0x1e4f0, 0x1e4f9,
 	0x1e7e0, 0x1e7e6,
 	0x1e7e8, 0x1e7eb,
 	0x1e7ed, 0x1e7ee,
@@ -19930,10 +20163,10 @@ static const OnigCodePoint CR_Grapheme_Base[] = {
 	0x1f250, 0x1f251,
 	0x1f260, 0x1f265,
 	0x1f300, 0x1f6d7,
-	0x1f6dd, 0x1f6ec,
+	0x1f6dc, 0x1f6ec,
 	0x1f6f0, 0x1f6fc,
-	0x1f700, 0x1f773,
-	0x1f780, 0x1f7d8,
+	0x1f700, 0x1f776,
+	0x1f77b, 0x1f7d9,
 	0x1f7e0, 0x1f7eb,
 	0x1f7f0, 0x1f7f0,
 	0x1f800, 0x1f80b,
@@ -19944,30 +20177,29 @@ static const OnigCodePoint CR_Grapheme_Base[] = {
 	0x1f8b0, 0x1f8b1,
 	0x1f900, 0x1fa53,
 	0x1fa60, 0x1fa6d,
-	0x1fa70, 0x1fa74,
-	0x1fa78, 0x1fa7c,
-	0x1fa80, 0x1fa86,
-	0x1fa90, 0x1faac,
-	0x1fab0, 0x1faba,
-	0x1fac0, 0x1fac5,
-	0x1fad0, 0x1fad9,
-	0x1fae0, 0x1fae7,
-	0x1faf0, 0x1faf6,
+	0x1fa70, 0x1fa7c,
+	0x1fa80, 0x1fa88,
+	0x1fa90, 0x1fabd,
+	0x1fabf, 0x1fac5,
+	0x1face, 0x1fadb,
+	0x1fae0, 0x1fae8,
+	0x1faf0, 0x1faf8,
 	0x1fb00, 0x1fb92,
 	0x1fb94, 0x1fbca,
 	0x1fbf0, 0x1fbf9,
 	0x20000, 0x2a6df,
-	0x2a700, 0x2b738,
+	0x2a700, 0x2b739,
 	0x2b740, 0x2b81d,
 	0x2b820, 0x2cea1,
 	0x2ceb0, 0x2ebe0,
 	0x2f800, 0x2fa1d,
 	0x30000, 0x3134a,
+	0x31350, 0x323af,
 }; /* CR_Grapheme_Base */
 
 /* 'Grapheme_Link': Derived Property */
 static const OnigCodePoint CR_Grapheme_Link[] = {
-	55,
+	56,
 	0x094d, 0x094d,
 	0x09cd, 0x09cd,
 	0x0a4d, 0x0a4d,
@@ -20023,11 +20255,12 @@ static const OnigCodePoint CR_Grapheme_Link[] = {
 	0x11c3f, 0x11c3f,
 	0x11d44, 0x11d45,
 	0x11d97, 0x11d97,
+	0x11f41, 0x11f42,
 }; /* CR_Grapheme_Link */
 
 /* 'Common': Script */
 static const OnigCodePoint CR_Common[] = {
-	174,
+	173,
 	0x0000, 0x0040,
 	0x005b, 0x0060,
 	0x007b, 0x00a9,
@@ -20134,6 +20367,7 @@ static const OnigCodePoint CR_Common[] = {
 	0x1d183, 0x1d184,
 	0x1d18c, 0x1d1a9,
 	0x1d1ae, 0x1d1ea,
+	0x1d2c0, 0x1d2d3,
 	0x1d2e0, 0x1d2f3,
 	0x1d300, 0x1d356,
 	0x1d360, 0x1d378,
@@ -20174,10 +20408,10 @@ static const OnigCodePoint CR_Common[] = {
 	0x1f250, 0x1f251,
 	0x1f260, 0x1f265,
 	0x1f300, 0x1f6d7,
-	0x1f6dd, 0x1f6ec,
+	0x1f6dc, 0x1f6ec,
 	0x1f6f0, 0x1f6fc,
-	0x1f700, 0x1f773,
-	0x1f780, 0x1f7d8,
+	0x1f700, 0x1f776,
+	0x1f77b, 0x1f7d9,
 	0x1f7e0, 0x1f7eb,
 	0x1f7f0, 0x1f7f0,
 	0x1f800, 0x1f80b,
@@ -20188,15 +20422,13 @@ static const OnigCodePoint CR_Common[] = {
 	0x1f8b0, 0x1f8b1,
 	0x1f900, 0x1fa53,
 	0x1fa60, 0x1fa6d,
-	0x1fa70, 0x1fa74,
-	0x1fa78, 0x1fa7c,
-	0x1fa80, 0x1fa86,
-	0x1fa90, 0x1faac,
-	0x1fab0, 0x1faba,
-	0x1fac0, 0x1fac5,
-	0x1fad0, 0x1fad9,
-	0x1fae0, 0x1fae7,
-	0x1faf0, 0x1faf6,
+	0x1fa70, 0x1fa7c,
+	0x1fa80, 0x1fa88,
+	0x1fa90, 0x1fabd,
+	0x1fabf, 0x1fac5,
+	0x1face, 0x1fadb,
+	0x1fae0, 0x1fae8,
+	0x1faf0, 0x1faf8,
 	0x1fb00, 0x1fb92,
 	0x1fb94, 0x1fbca,
 	0x1fbf0, 0x1fbf9,
@@ -20206,7 +20438,7 @@ static const OnigCodePoint CR_Common[] = {
 
 /* 'Latin': Script */
 static const OnigCodePoint CR_Latin[] = {
-	38,
+	39,
 	0x0041, 0x005a,
 	0x0061, 0x007a,
 	0x00aa, 0x00aa,
@@ -20245,6 +20477,7 @@ static const OnigCodePoint CR_Latin[] = {
 	0x10787, 0x107b0,
 	0x107b2, 0x107ba,
 	0x1df00, 0x1df1e,
+	0x1df25, 0x1df2a,
 }; /* CR_Latin */
 
 /* 'Greek': Script */
@@ -20290,7 +20523,7 @@ static const OnigCodePoint CR_Greek[] = {
 
 /* 'Cyrillic': Script */
 static const OnigCodePoint CR_Cyrillic[] = {
-	8,
+	10,
 	0x0400, 0x0484,
 	0x0487, 0x052f,
 	0x1c80, 0x1c88,
@@ -20299,6 +20532,8 @@ static const OnigCodePoint CR_Cyrillic[] = {
 	0x2de0, 0x2dff,
 	0xa640, 0xa69f,
 	0xfe2e, 0xfe2f,
+	0x1e030, 0x1e06d,
+	0x1e08f, 0x1e08f,
 }; /* CR_Cyrillic */
 
 /* 'Armenian': Script */
@@ -20326,7 +20561,7 @@ static const OnigCodePoint CR_Hebrew[] = {
 
 /* 'Arabic': Script */
 static const OnigCodePoint CR_Arabic[] = {
-	57,
+	58,
 	0x0600, 0x0604,
 	0x0606, 0x060b,
 	0x060d, 0x061a,
@@ -20350,6 +20585,7 @@ static const OnigCodePoint CR_Arabic[] = {
 	0xfe70, 0xfe74,
 	0xfe76, 0xfefc,
 	0x10e60, 0x10e7e,
+	0x10efd, 0x10eff,
 	0x1ee00, 0x1ee03,
 	0x1ee05, 0x1ee1f,
 	0x1ee21, 0x1ee22,
@@ -20403,11 +20639,12 @@ static const OnigCodePoint CR_Thaana[] = {
 
 /* 'Devanagari': Script */
 static const OnigCodePoint CR_Devanagari[] = {
-	4,
+	5,
 	0x0900, 0x0950,
 	0x0955, 0x0963,
 	0x0966, 0x097f,
 	0xa8e0, 0xa8ff,
+	0x11b00, 0x11b09,
 }; /* CR_Devanagari */
 
 /* 'Bengali': Script */
@@ -20544,7 +20781,7 @@ static const OnigCodePoint CR_Kannada[] = {
 	0x0cdd, 0x0cde,
 	0x0ce0, 0x0ce3,
 	0x0ce6, 0x0cef,
-	0x0cf1, 0x0cf2,
+	0x0cf1, 0x0cf3,
 }; /* CR_Kannada */
 
 /* 'Malayalam': Script */
@@ -20595,7 +20832,7 @@ static const OnigCodePoint CR_Lao[] = {
 	0x0ea7, 0x0ebd,
 	0x0ec0, 0x0ec4,
 	0x0ec6, 0x0ec6,
-	0x0ec8, 0x0ecd,
+	0x0ec8, 0x0ece,
 	0x0ed0, 0x0ed9,
 	0x0edc, 0x0edf,
 }; /* CR_Lao */
@@ -20746,17 +20983,18 @@ static const OnigCodePoint CR_Mongolian[] = {
 
 /* 'Hiragana': Script */
 static const OnigCodePoint CR_Hiragana[] = {
-	5,
+	6,
 	0x3041, 0x3096,
 	0x309d, 0x309f,
 	0x1b001, 0x1b11f,
+	0x1b132, 0x1b132,
 	0x1b150, 0x1b152,
 	0x1f200, 0x1f200,
 }; /* CR_Hiragana */
 
 /* 'Katakana': Script */
 static const OnigCodePoint CR_Katakana[] = {
-	13,
+	14,
 	0x30a1, 0x30fa,
 	0x30fd, 0x30ff,
 	0x31f0, 0x31ff,
@@ -20769,6 +21007,7 @@ static const OnigCodePoint CR_Katakana[] = {
 	0x1affd, 0x1affe,
 	0x1b000, 0x1b000,
 	0x1b120, 0x1b122,
+	0x1b155, 0x1b155,
 	0x1b164, 0x1b167,
 }; /* CR_Katakana */
 
@@ -20782,7 +21021,7 @@ static const OnigCodePoint CR_Bopomofo[] = {
 
 /* 'Han': Script */
 static const OnigCodePoint CR_Han[] = {
-	20,
+	21,
 	0x2e80, 0x2e99,
 	0x2e9b, 0x2ef3,
 	0x2f00, 0x2fd5,
@@ -20797,12 +21036,13 @@ static const OnigCodePoint CR_Han[] = {
 	0x16fe2, 0x16fe3,
 	0x16ff0, 0x16ff1,
 	0x20000, 0x2a6df,
-	0x2a700, 0x2b738,
+	0x2a700, 0x2b739,
 	0x2b740, 0x2b81d,
 	0x2b820, 0x2cea1,
 	0x2ceb0, 0x2ebe0,
 	0x2f800, 0x2fa1d,
 	0x30000, 0x3134a,
+	0x31350, 0x323af,
 }; /* CR_Han */
 
 /* 'Yi': Script */
@@ -21165,9 +21405,8 @@ static const OnigCodePoint CR_Avestan[] = {
 
 /* 'Egyptian_Hieroglyphs': Script */
 static const OnigCodePoint CR_Egyptian_Hieroglyphs[] = {
-	2,
-	0x13000, 0x1342e,
-	0x13430, 0x13438,
+	1,
+	0x13000, 0x13455,
 }; /* CR_Egyptian_Hieroglyphs */
 
 /* 'Samaritan': Script */
@@ -21382,7 +21621,7 @@ static const OnigCodePoint CR_Pahawh_Hmong[] = {
 static const OnigCodePoint CR_Khojki[] = {
 	2,
 	0x11200, 0x11211,
-	0x11213, 0x1123e,
+	0x11213, 0x11241,
 }; /* CR_Khojki */
 
 /* 'Linear_A': Script */
@@ -21772,6 +22011,20 @@ static const OnigCodePoint CR_Vithkuqi[] = {
 	0x105bb, 0x105bc,
 }; /* CR_Vithkuqi */
 
+/* 'Kawi': Script */
+static const OnigCodePoint CR_Kawi[] = {
+	3,
+	0x11f00, 0x11f10,
+	0x11f12, 0x11f3a,
+	0x11f3e, 0x11f59,
+}; /* CR_Kawi */
+
+/* 'Nag_Mundari': Script */
+static const OnigCodePoint CR_Nag_Mundari[] = {
+	1,
+	0x1e4d0, 0x1e4f9,
+}; /* CR_Nag_Mundari */
+
 /* 'White_Space': Binary Property */
 #define CR_White_Space CR_Space
 
@@ -21853,7 +22106,7 @@ static const OnigCodePoint CR_Quotation_Mark[] = {
 
 /* 'Terminal_Punctuation': Binary Property */
 static const OnigCodePoint CR_Terminal_Punctuation[] = {
-	107,
+	108,
 	0x0021, 0x0021,
 	0x002c, 0x002c,
 	0x002e, 0x002e,
@@ -21953,6 +22206,7 @@ static const OnigCodePoint CR_Terminal_Punctuation[] = {
 	0x11c41, 0x11c43,
 	0x11c71, 0x11c71,
 	0x11ef7, 0x11ef8,
+	0x11f43, 0x11f44,
 	0x12470, 0x12474,
 	0x16a6e, 0x16a6f,
 	0x16af5, 0x16af5,
@@ -22118,7 +22372,7 @@ static const OnigCodePoint CR_Hex_Digit[] = {
 
 /* 'Other_Alphabetic': Binary Property */
 static const OnigCodePoint CR_Other_Alphabetic[] = {
-	233,
+	240,
 	0x0345, 0x0345,
 	0x05b0, 0x05bd,
 	0x05bf, 0x05bf,
@@ -22178,7 +22432,7 @@ static const OnigCodePoint CR_Other_Alphabetic[] = {
 	0x0bc6, 0x0bc8,
 	0x0bca, 0x0bcc,
 	0x0bd7, 0x0bd7,
-	0x0c00, 0x0c03,
+	0x0c00, 0x0c04,
 	0x0c3e, 0x0c44,
 	0x0c46, 0x0c48,
 	0x0c4a, 0x0c4c,
@@ -22190,6 +22444,7 @@ static const OnigCodePoint CR_Other_Alphabetic[] = {
 	0x0cca, 0x0ccc,
 	0x0cd5, 0x0cd6,
 	0x0ce2, 0x0ce3,
+	0x0cf3, 0x0cf3,
 	0x0d00, 0x0d03,
 	0x0d3e, 0x0d44,
 	0x0d46, 0x0d48,
@@ -22208,7 +22463,7 @@ static const OnigCodePoint CR_Other_Alphabetic[] = {
 	0x0eb4, 0x0eb9,
 	0x0ebb, 0x0ebc,
 	0x0ecd, 0x0ecd,
-	0x0f71, 0x0f81,
+	0x0f71, 0x0f83,
 	0x0f8d, 0x0f97,
 	0x0f99, 0x0fbc,
 	0x102b, 0x1036,
@@ -22281,7 +22536,7 @@ static const OnigCodePoint CR_Other_Alphabetic[] = {
 	0x11000, 0x11002,
 	0x11038, 0x11045,
 	0x11073, 0x11074,
-	0x11082, 0x11082,
+	0x11080, 0x11082,
 	0x110b0, 0x110b8,
 	0x110c2, 0x110c2,
 	0x11100, 0x11102,
@@ -22293,6 +22548,7 @@ static const OnigCodePoint CR_Other_Alphabetic[] = {
 	0x1122c, 0x11234,
 	0x11237, 0x11237,
 	0x1123e, 0x1123e,
+	0x11241, 0x11241,
 	0x112df, 0x112e8,
 	0x11300, 0x11303,
 	0x1133e, 0x11344,
@@ -22338,6 +22594,10 @@ static const OnigCodePoint CR_Other_Alphabetic[] = {
 	0x11d90, 0x11d91,
 	0x11d93, 0x11d96,
 	0x11ef3, 0x11ef6,
+	0x11f00, 0x11f01,
+	0x11f03, 0x11f03,
+	0x11f34, 0x11f3a,
+	0x11f3e, 0x11f40,
 	0x16f4f, 0x16f4f,
 	0x16f51, 0x16f87,
 	0x16f8f, 0x16f92,
@@ -22348,6 +22608,7 @@ static const OnigCodePoint CR_Other_Alphabetic[] = {
 	0x1e01b, 0x1e021,
 	0x1e023, 0x1e024,
 	0x1e026, 0x1e02a,
+	0x1e08f, 0x1e08f,
 	0x1e947, 0x1e947,
 	0x1f130, 0x1f149,
 	0x1f150, 0x1f169,
@@ -22356,7 +22617,7 @@ static const OnigCodePoint CR_Other_Alphabetic[] = {
 
 /* 'Ideographic': Binary Property */
 static const OnigCodePoint CR_Ideographic[] = {
-	19,
+	20,
 	0x3006, 0x3007,
 	0x3021, 0x3029,
 	0x3038, 0x303a,
@@ -22370,17 +22631,18 @@ static const OnigCodePoint CR_Ideographic[] = {
 	0x18d00, 0x18d08,
 	0x1b170, 0x1b2fb,
 	0x20000, 0x2a6df,
-	0x2a700, 0x2b738,
+	0x2a700, 0x2b739,
 	0x2b740, 0x2b81d,
 	0x2b820, 0x2cea1,
 	0x2ceb0, 0x2ebe0,
 	0x2f800, 0x2fa1d,
 	0x30000, 0x3134a,
+	0x31350, 0x323af,
 }; /* CR_Ideographic */
 
 /* 'Diacritic': Binary Property */
 static const OnigCodePoint CR_Diacritic[] = {
-	192,
+	195,
 	0x005e, 0x005e,
 	0x0060, 0x0060,
 	0x00a8, 0x00a8,
@@ -22520,6 +22782,7 @@ static const OnigCodePoint CR_Diacritic[] = {
 	0x107b2, 0x107ba,
 	0x10ae5, 0x10ae6,
 	0x10d22, 0x10d27,
+	0x10efd, 0x10eff,
 	0x10f46, 0x10f50,
 	0x10f82, 0x10f85,
 	0x11046, 0x11046,
@@ -22553,6 +22816,7 @@ static const OnigCodePoint CR_Diacritic[] = {
 	0x11d42, 0x11d42,
 	0x11d44, 0x11d45,
 	0x11d97, 0x11d97,
+	0x13447, 0x13455,
 	0x16af0, 0x16af4,
 	0x16b30, 0x16b36,
 	0x16f8f, 0x16f9f,
@@ -22567,6 +22831,7 @@ static const OnigCodePoint CR_Diacritic[] = {
 	0x1d17b, 0x1d182,
 	0x1d185, 0x1d18b,
 	0x1d1aa, 0x1d1ad,
+	0x1e030, 0x1e06d,
 	0x1e130, 0x1e136,
 	0x1e2ae, 0x1e2ae,
 	0x1e2ec, 0x1e2ef,
@@ -22615,7 +22880,7 @@ static const OnigCodePoint CR_Extender[] = {
 
 /* 'Other_Lowercase': Binary Property */
 static const OnigCodePoint CR_Other_Lowercase[] = {
-	20,
+	28,
 	0x00aa, 0x00aa,
 	0x00ba, 0x00ba,
 	0x02b0, 0x02b8,
@@ -22623,6 +22888,7 @@ static const OnigCodePoint CR_Other_Lowercase[] = {
 	0x02e0, 0x02e4,
 	0x0345, 0x0345,
 	0x037a, 0x037a,
+	0x10fc, 0x10fc,
 	0x1d2c, 0x1d6a,
 	0x1d78, 0x1d78,
 	0x1d9b, 0x1dbf,
@@ -22634,8 +22900,15 @@ static const OnigCodePoint CR_Other_Lowercase[] = {
 	0x2c7c, 0x2c7d,
 	0xa69c, 0xa69d,
 	0xa770, 0xa770,
+	0xa7f2, 0xa7f4,
 	0xa7f8, 0xa7f9,
 	0xab5c, 0xab5f,
+	0xab69, 0xab69,
+	0x10780, 0x10780,
+	0x10783, 0x10785,
+	0x10787, 0x107b0,
+	0x107b2, 0x107ba,
+	0x1e030, 0x1e06d,
 }; /* CR_Other_Lowercase */
 
 /* 'Other_Uppercase': Binary Property */
@@ -22724,7 +22997,7 @@ static const OnigCodePoint CR_Radical[] = {
 
 /* 'Unified_Ideograph': Binary Property */
 static const OnigCodePoint CR_Unified_Ideograph[] = {
-	15,
+	16,
 	0x3400, 0x4dbf,
 	0x4e00, 0x9fff,
 	0xfa0e, 0xfa0f,
@@ -22735,11 +23008,12 @@ static const OnigCodePoint CR_Unified_Ideograph[] = {
 	0xfa23, 0xfa24,
 	0xfa27, 0xfa29,
 	0x20000, 0x2a6df,
-	0x2a700, 0x2b738,
+	0x2a700, 0x2b739,
 	0x2b740, 0x2b81d,
 	0x2b820, 0x2cea1,
 	0x2ceb0, 0x2ebe0,
 	0x30000, 0x3134a,
+	0x31350, 0x323af,
 }; /* CR_Unified_Ideograph */
 
 /* 'Other_Default_Ignorable_Code_Point': Binary Property */
@@ -22773,7 +23047,7 @@ static const OnigCodePoint CR_Deprecated[] = {
 
 /* 'Soft_Dotted': Binary Property */
 static const OnigCodePoint CR_Soft_Dotted[] = {
-	32,
+	34,
 	0x0069, 0x006a,
 	0x012f, 0x012f,
 	0x0249, 0x0249,
@@ -22806,6 +23080,8 @@ static const OnigCodePoint CR_Soft_Dotted[] = {
 	0x1d65e, 0x1d65f,
 	0x1d692, 0x1d693,
 	0x1df1a, 0x1df1a,
+	0x1e04c, 0x1e04d,
+	0x1e068, 0x1e068,
 }; /* CR_Soft_Dotted */
 
 /* 'Logical_Order_Exception': Binary Property */
@@ -22840,7 +23116,7 @@ static const OnigCodePoint CR_Other_ID_Continue[] = {
 
 /* 'Sentence_Terminal': Binary Property */
 static const OnigCodePoint CR_Sentence_Terminal[] = {
-	79,
+	80,
 	0x0021, 0x0021,
 	0x002e, 0x002e,
 	0x003f, 0x003f,
@@ -22913,6 +23189,7 @@ static const OnigCodePoint CR_Sentence_Terminal[] = {
 	0x11a9b, 0x11a9c,
 	0x11c41, 0x11c42,
 	0x11ef7, 0x11ef8,
+	0x11f43, 0x11f44,
 	0x16a6e, 0x16a6f,
 	0x16af5, 0x16af5,
 	0x16b37, 0x16b38,
@@ -22994,7 +23271,7 @@ static const OnigCodePoint CR_Regional_Indicator[] = {
 
 /* 'Emoji': Emoji */
 static const OnigCodePoint CR_Emoji[] = {
-	153,
+	151,
 	0x0023, 0x0023,
 	0x002a, 0x002a,
 	0x0030, 0x0039,
@@ -23129,7 +23406,7 @@ static const OnigCodePoint CR_Emoji[] = {
 	0x1f680, 0x1f6c5,
 	0x1f6cb, 0x1f6d2,
 	0x1f6d5, 0x1f6d7,
-	0x1f6dd, 0x1f6e5,
+	0x1f6dc, 0x1f6e5,
 	0x1f6e9, 0x1f6e9,
 	0x1f6eb, 0x1f6ec,
 	0x1f6f0, 0x1f6f0,
@@ -23139,20 +23416,18 @@ static const OnigCodePoint CR_Emoji[] = {
 	0x1f90c, 0x1f93a,
 	0x1f93c, 0x1f945,
 	0x1f947, 0x1f9ff,
-	0x1fa70, 0x1fa74,
-	0x1fa78, 0x1fa7c,
-	0x1fa80, 0x1fa86,
-	0x1fa90, 0x1faac,
-	0x1fab0, 0x1faba,
-	0x1fac0, 0x1fac5,
-	0x1fad0, 0x1fad9,
-	0x1fae0, 0x1fae7,
-	0x1faf0, 0x1faf6,
+	0x1fa70, 0x1fa7c,
+	0x1fa80, 0x1fa88,
+	0x1fa90, 0x1fabd,
+	0x1fabf, 0x1fac5,
+	0x1face, 0x1fadb,
+	0x1fae0, 0x1fae8,
+	0x1faf0, 0x1faf8,
 }; /* CR_Emoji */
 
 /* 'Emoji_Presentation': Emoji */
 static const OnigCodePoint CR_Emoji_Presentation[] = {
-	83,
+	81,
 	0x231a, 0x231b,
 	0x23e9, 0x23ec,
 	0x23f0, 0x23f0,
@@ -23219,7 +23494,7 @@ static const OnigCodePoint CR_Emoji_Presentation[] = {
 	0x1f6cc, 0x1f6cc,
 	0x1f6d0, 0x1f6d2,
 	0x1f6d5, 0x1f6d7,
-	0x1f6dd, 0x1f6df,
+	0x1f6dc, 0x1f6df,
 	0x1f6eb, 0x1f6ec,
 	0x1f6f4, 0x1f6fc,
 	0x1f7e0, 0x1f7eb,
@@ -23227,15 +23502,13 @@ static const OnigCodePoint CR_Emoji_Presentation[] = {
 	0x1f90c, 0x1f93a,
 	0x1f93c, 0x1f945,
 	0x1f947, 0x1f9ff,
-	0x1fa70, 0x1fa74,
-	0x1fa78, 0x1fa7c,
-	0x1fa80, 0x1fa86,
-	0x1fa90, 0x1faac,
-	0x1fab0, 0x1faba,
-	0x1fac0, 0x1fac5,
-	0x1fad0, 0x1fad9,
-	0x1fae0, 0x1fae7,
-	0x1faf0, 0x1faf6,
+	0x1fa70, 0x1fa7c,
+	0x1fa80, 0x1fa88,
+	0x1fa90, 0x1fabd,
+	0x1fabf, 0x1fac5,
+	0x1face, 0x1fadb,
+	0x1fae0, 0x1fae8,
+	0x1faf0, 0x1faf8,
 }; /* CR_Emoji_Presentation */
 
 /* 'Emoji_Modifier': Emoji */
@@ -23286,7 +23559,7 @@ static const OnigCodePoint CR_Emoji_Modifier_Base[] = {
 	0x1f9cd, 0x1f9cf,
 	0x1f9d1, 0x1f9dd,
 	0x1fac3, 0x1fac5,
-	0x1faf0, 0x1faf6,
+	0x1faf0, 0x1faf8,
 }; /* CR_Emoji_Modifier_Base */
 
 /* 'Emoji_Component': Emoji */
@@ -23389,7 +23662,7 @@ static const OnigCodePoint CR_Extended_Pictographic[] = {
 
 /* 'Unknown': Script */
 static const OnigCodePoint CR_Unknown[] = {
-	696,
+	705,
 	0x0378, 0x0379,
 	0x0380, 0x0383,
 	0x038b, 0x038b,
@@ -23511,7 +23784,7 @@ static const OnigCodePoint CR_Unknown[] = {
 	0x0cdf, 0x0cdf,
 	0x0ce4, 0x0ce5,
 	0x0cf0, 0x0cf0,
-	0x0cf3, 0x0cff,
+	0x0cf4, 0x0cff,
 	0x0d0d, 0x0d0d,
 	0x0d11, 0x0d11,
 	0x0d45, 0x0d45,
@@ -23541,7 +23814,7 @@ static const OnigCodePoint CR_Unknown[] = {
 	0x0ebe, 0x0ebf,
 	0x0ec5, 0x0ec5,
 	0x0ec7, 0x0ec7,
-	0x0ece, 0x0ecf,
+	0x0ecf, 0x0ecf,
 	0x0eda, 0x0edb,
 	0x0ee0, 0x0eff,
 	0x0f48, 0x0f48,
@@ -23811,7 +24084,7 @@ static const OnigCodePoint CR_Unknown[] = {
 	0x10e7f, 0x10e7f,
 	0x10eaa, 0x10eaa,
 	0x10eae, 0x10eaf,
-	0x10eb2, 0x10eff,
+	0x10eb2, 0x10efc,
 	0x10f28, 0x10f2f,
 	0x10f5a, 0x10f6f,
 	0x10f8a, 0x10faf,
@@ -23829,7 +24102,7 @@ static const OnigCodePoint CR_Unknown[] = {
 	0x111e0, 0x111e0,
 	0x111f5, 0x111ff,
 	0x11212, 0x11212,
-	0x1123f, 0x1127f,
+	0x11242, 0x1127f,
 	0x11287, 0x11287,
 	0x11289, 0x11289,
 	0x1128e, 0x1128e,
@@ -23881,7 +24154,8 @@ static const OnigCodePoint CR_Unknown[] = {
 	0x119e5, 0x119ff,
 	0x11a48, 0x11a4f,
 	0x11aa3, 0x11aaf,
-	0x11af9, 0x11bff,
+	0x11af9, 0x11aff,
+	0x11b0a, 0x11bff,
 	0x11c09, 0x11c09,
 	0x11c37, 0x11c37,
 	0x11c46, 0x11c4f,
@@ -23902,7 +24176,10 @@ static const OnigCodePoint CR_Unknown[] = {
 	0x11d92, 0x11d92,
 	0x11d99, 0x11d9f,
 	0x11daa, 0x11edf,
-	0x11ef9, 0x11faf,
+	0x11ef9, 0x11eff,
+	0x11f11, 0x11f11,
+	0x11f3b, 0x11f3d,
+	0x11f5a, 0x11faf,
 	0x11fb1, 0x11fbf,
 	0x11ff2, 0x11ffe,
 	0x1239a, 0x123ff,
@@ -23910,8 +24187,7 @@ static const OnigCodePoint CR_Unknown[] = {
 	0x12475, 0x1247f,
 	0x12544, 0x12f8f,
 	0x12ff3, 0x12fff,
-	0x1342f, 0x1342f,
-	0x13439, 0x143ff,
+	0x13456, 0x143ff,
 	0x14647, 0x167ff,
 	0x16a39, 0x16a3f,
 	0x16a5f, 0x16a5f,
@@ -23937,8 +24213,10 @@ static const OnigCodePoint CR_Unknown[] = {
 	0x1aff4, 0x1aff4,
 	0x1affc, 0x1affc,
 	0x1afff, 0x1afff,
-	0x1b123, 0x1b14f,
-	0x1b153, 0x1b163,
+	0x1b123, 0x1b131,
+	0x1b133, 0x1b14f,
+	0x1b153, 0x1b154,
+	0x1b156, 0x1b163,
 	0x1b168, 0x1b16f,
 	0x1b2fc, 0x1bbff,
 	0x1bc6b, 0x1bc6f,
@@ -23952,7 +24230,8 @@ static const OnigCodePoint CR_Unknown[] = {
 	0x1d0f6, 0x1d0ff,
 	0x1d127, 0x1d128,
 	0x1d1eb, 0x1d1ff,
-	0x1d246, 0x1d2df,
+	0x1d246, 0x1d2bf,
+	0x1d2d4, 0x1d2df,
 	0x1d2f4, 0x1d2ff,
 	0x1d357, 0x1d35f,
 	0x1d379, 0x1d3ff,
@@ -23979,19 +24258,23 @@ static const OnigCodePoint CR_Unknown[] = {
 	0x1da8c, 0x1da9a,
 	0x1daa0, 0x1daa0,
 	0x1dab0, 0x1deff,
-	0x1df1f, 0x1dfff,
+	0x1df1f, 0x1df24,
+	0x1df2b, 0x1dfff,
 	0x1e007, 0x1e007,
 	0x1e019, 0x1e01a,
 	0x1e022, 0x1e022,
 	0x1e025, 0x1e025,
-	0x1e02b, 0x1e0ff,
+	0x1e02b, 0x1e02f,
+	0x1e06e, 0x1e08e,
+	0x1e090, 0x1e0ff,
 	0x1e12d, 0x1e12f,
 	0x1e13e, 0x1e13f,
 	0x1e14a, 0x1e14d,
 	0x1e150, 0x1e28f,
 	0x1e2af, 0x1e2bf,
 	0x1e2fa, 0x1e2fe,
-	0x1e300, 0x1e7df,
+	0x1e300, 0x1e4cf,
+	0x1e4fa, 0x1e7df,
 	0x1e7e7, 0x1e7e7,
 	0x1e7ec, 0x1e7ec,
 	0x1e7ef, 0x1e7ef,
@@ -24049,11 +24332,11 @@ static const OnigCodePoint CR_Unknown[] = {
 	0x1f249, 0x1f24f,
 	0x1f252, 0x1f25f,
 	0x1f266, 0x1f2ff,
-	0x1f6d8, 0x1f6dc,
+	0x1f6d8, 0x1f6db,
 	0x1f6ed, 0x1f6ef,
 	0x1f6fd, 0x1f6ff,
-	0x1f774, 0x1f77f,
-	0x1f7d9, 0x1f7df,
+	0x1f777, 0x1f77a,
+	0x1f7da, 0x1f7df,
 	0x1f7ec, 0x1f7ef,
 	0x1f7f1, 0x1f7ff,
 	0x1f80c, 0x1f80f,
@@ -24064,25 +24347,24 @@ static const OnigCodePoint CR_Unknown[] = {
 	0x1f8b2, 0x1f8ff,
 	0x1fa54, 0x1fa5f,
 	0x1fa6e, 0x1fa6f,
-	0x1fa75, 0x1fa77,
 	0x1fa7d, 0x1fa7f,
-	0x1fa87, 0x1fa8f,
-	0x1faad, 0x1faaf,
-	0x1fabb, 0x1fabf,
-	0x1fac6, 0x1facf,
-	0x1fada, 0x1fadf,
-	0x1fae8, 0x1faef,
-	0x1faf7, 0x1faff,
+	0x1fa89, 0x1fa8f,
+	0x1fabe, 0x1fabe,
+	0x1fac6, 0x1facd,
+	0x1fadc, 0x1fadf,
+	0x1fae9, 0x1faef,
+	0x1faf9, 0x1faff,
 	0x1fb93, 0x1fb93,
 	0x1fbcb, 0x1fbef,
 	0x1fbfa, 0x1ffff,
 	0x2a6e0, 0x2a6ff,
-	0x2b739, 0x2b73f,
+	0x2b73a, 0x2b73f,
 	0x2b81e, 0x2b81f,
 	0x2cea2, 0x2ceaf,
 	0x2ebe1, 0x2f7ff,
 	0x2fa1e, 0x2ffff,
-	0x3134b, 0xe0000,
+	0x3134b, 0x3134f,
+	0x323b0, 0xe0000,
 	0xe0002, 0xe001f,
 	0xe0080, 0xe00ff,
 	0xe01f0, 0x10ffff,
@@ -36632,10 +36914,730 @@ static const OnigCodePoint CR_Age_14_0[] = {
 	0xefffe, 0x10ffff,
 }; /* CR_Age_14_0 */
 
+/* 'Age_15_0': Derived Age 15.0 */
+static const OnigCodePoint CR_Age_15_0[] = {
+	715,
+	0x0000, 0x0377,
+	0x037a, 0x037f,
+	0x0384, 0x038a,
+	0x038c, 0x038c,
+	0x038e, 0x03a1,
+	0x03a3, 0x052f,
+	0x0531, 0x0556,
+	0x0559, 0x058a,
+	0x058d, 0x058f,
+	0x0591, 0x05c7,
+	0x05d0, 0x05ea,
+	0x05ef, 0x05f4,
+	0x0600, 0x070d,
+	0x070f, 0x074a,
+	0x074d, 0x07b1,
+	0x07c0, 0x07fa,
+	0x07fd, 0x082d,
+	0x0830, 0x083e,
+	0x0840, 0x085b,
+	0x085e, 0x085e,
+	0x0860, 0x086a,
+	0x0870, 0x088e,
+	0x0890, 0x0891,
+	0x0898, 0x0983,
+	0x0985, 0x098c,
+	0x098f, 0x0990,
+	0x0993, 0x09a8,
+	0x09aa, 0x09b0,
+	0x09b2, 0x09b2,
+	0x09b6, 0x09b9,
+	0x09bc, 0x09c4,
+	0x09c7, 0x09c8,
+	0x09cb, 0x09ce,
+	0x09d7, 0x09d7,
+	0x09dc, 0x09dd,
+	0x09df, 0x09e3,
+	0x09e6, 0x09fe,
+	0x0a01, 0x0a03,
+	0x0a05, 0x0a0a,
+	0x0a0f, 0x0a10,
+	0x0a13, 0x0a28,
+	0x0a2a, 0x0a30,
+	0x0a32, 0x0a33,
+	0x0a35, 0x0a36,
+	0x0a38, 0x0a39,
+	0x0a3c, 0x0a3c,
+	0x0a3e, 0x0a42,
+	0x0a47, 0x0a48,
+	0x0a4b, 0x0a4d,
+	0x0a51, 0x0a51,
+	0x0a59, 0x0a5c,
+	0x0a5e, 0x0a5e,
+	0x0a66, 0x0a76,
+	0x0a81, 0x0a83,
+	0x0a85, 0x0a8d,
+	0x0a8f, 0x0a91,
+	0x0a93, 0x0aa8,
+	0x0aaa, 0x0ab0,
+	0x0ab2, 0x0ab3,
+	0x0ab5, 0x0ab9,
+	0x0abc, 0x0ac5,
+	0x0ac7, 0x0ac9,
+	0x0acb, 0x0acd,
+	0x0ad0, 0x0ad0,
+	0x0ae0, 0x0ae3,
+	0x0ae6, 0x0af1,
+	0x0af9, 0x0aff,
+	0x0b01, 0x0b03,
+	0x0b05, 0x0b0c,
+	0x0b0f, 0x0b10,
+	0x0b13, 0x0b28,
+	0x0b2a, 0x0b30,
+	0x0b32, 0x0b33,
+	0x0b35, 0x0b39,
+	0x0b3c, 0x0b44,
+	0x0b47, 0x0b48,
+	0x0b4b, 0x0b4d,
+	0x0b55, 0x0b57,
+	0x0b5c, 0x0b5d,
+	0x0b5f, 0x0b63,
+	0x0b66, 0x0b77,
+	0x0b82, 0x0b83,
+	0x0b85, 0x0b8a,
+	0x0b8e, 0x0b90,
+	0x0b92, 0x0b95,
+	0x0b99, 0x0b9a,
+	0x0b9c, 0x0b9c,
+	0x0b9e, 0x0b9f,
+	0x0ba3, 0x0ba4,
+	0x0ba8, 0x0baa,
+	0x0bae, 0x0bb9,
+	0x0bbe, 0x0bc2,
+	0x0bc6, 0x0bc8,
+	0x0bca, 0x0bcd,
+	0x0bd0, 0x0bd0,
+	0x0bd7, 0x0bd7,
+	0x0be6, 0x0bfa,
+	0x0c00, 0x0c0c,
+	0x0c0e, 0x0c10,
+	0x0c12, 0x0c28,
+	0x0c2a, 0x0c39,
+	0x0c3c, 0x0c44,
+	0x0c46, 0x0c48,
+	0x0c4a, 0x0c4d,
+	0x0c55, 0x0c56,
+	0x0c58, 0x0c5a,
+	0x0c5d, 0x0c5d,
+	0x0c60, 0x0c63,
+	0x0c66, 0x0c6f,
+	0x0c77, 0x0c8c,
+	0x0c8e, 0x0c90,
+	0x0c92, 0x0ca8,
+	0x0caa, 0x0cb3,
+	0x0cb5, 0x0cb9,
+	0x0cbc, 0x0cc4,
+	0x0cc6, 0x0cc8,
+	0x0cca, 0x0ccd,
+	0x0cd5, 0x0cd6,
+	0x0cdd, 0x0cde,
+	0x0ce0, 0x0ce3,
+	0x0ce6, 0x0cef,
+	0x0cf1, 0x0cf3,
+	0x0d00, 0x0d0c,
+	0x0d0e, 0x0d10,
+	0x0d12, 0x0d44,
+	0x0d46, 0x0d48,
+	0x0d4a, 0x0d4f,
+	0x0d54, 0x0d63,
+	0x0d66, 0x0d7f,
+	0x0d81, 0x0d83,
+	0x0d85, 0x0d96,
+	0x0d9a, 0x0db1,
+	0x0db3, 0x0dbb,
+	0x0dbd, 0x0dbd,
+	0x0dc0, 0x0dc6,
+	0x0dca, 0x0dca,
+	0x0dcf, 0x0dd4,
+	0x0dd6, 0x0dd6,
+	0x0dd8, 0x0ddf,
+	0x0de6, 0x0def,
+	0x0df2, 0x0df4,
+	0x0e01, 0x0e3a,
+	0x0e3f, 0x0e5b,
+	0x0e81, 0x0e82,
+	0x0e84, 0x0e84,
+	0x0e86, 0x0e8a,
+	0x0e8c, 0x0ea3,
+	0x0ea5, 0x0ea5,
+	0x0ea7, 0x0ebd,
+	0x0ec0, 0x0ec4,
+	0x0ec6, 0x0ec6,
+	0x0ec8, 0x0ece,
+	0x0ed0, 0x0ed9,
+	0x0edc, 0x0edf,
+	0x0f00, 0x0f47,
+	0x0f49, 0x0f6c,
+	0x0f71, 0x0f97,
+	0x0f99, 0x0fbc,
+	0x0fbe, 0x0fcc,
+	0x0fce, 0x0fda,
+	0x1000, 0x10c5,
+	0x10c7, 0x10c7,
+	0x10cd, 0x10cd,
+	0x10d0, 0x1248,
+	0x124a, 0x124d,
+	0x1250, 0x1256,
+	0x1258, 0x1258,
+	0x125a, 0x125d,
+	0x1260, 0x1288,
+	0x128a, 0x128d,
+	0x1290, 0x12b0,
+	0x12b2, 0x12b5,
+	0x12b8, 0x12be,
+	0x12c0, 0x12c0,
+	0x12c2, 0x12c5,
+	0x12c8, 0x12d6,
+	0x12d8, 0x1310,
+	0x1312, 0x1315,
+	0x1318, 0x135a,
+	0x135d, 0x137c,
+	0x1380, 0x1399,
+	0x13a0, 0x13f5,
+	0x13f8, 0x13fd,
+	0x1400, 0x169c,
+	0x16a0, 0x16f8,
+	0x1700, 0x1715,
+	0x171f, 0x1736,
+	0x1740, 0x1753,
+	0x1760, 0x176c,
+	0x176e, 0x1770,
+	0x1772, 0x1773,
+	0x1780, 0x17dd,
+	0x17e0, 0x17e9,
+	0x17f0, 0x17f9,
+	0x1800, 0x1819,
+	0x1820, 0x1878,
+	0x1880, 0x18aa,
+	0x18b0, 0x18f5,
+	0x1900, 0x191e,
+	0x1920, 0x192b,
+	0x1930, 0x193b,
+	0x1940, 0x1940,
+	0x1944, 0x196d,
+	0x1970, 0x1974,
+	0x1980, 0x19ab,
+	0x19b0, 0x19c9,
+	0x19d0, 0x19da,
+	0x19de, 0x1a1b,
+	0x1a1e, 0x1a5e,
+	0x1a60, 0x1a7c,
+	0x1a7f, 0x1a89,
+	0x1a90, 0x1a99,
+	0x1aa0, 0x1aad,
+	0x1ab0, 0x1ace,
+	0x1b00, 0x1b4c,
+	0x1b50, 0x1b7e,
+	0x1b80, 0x1bf3,
+	0x1bfc, 0x1c37,
+	0x1c3b, 0x1c49,
+	0x1c4d, 0x1c88,
+	0x1c90, 0x1cba,
+	0x1cbd, 0x1cc7,
+	0x1cd0, 0x1cfa,
+	0x1d00, 0x1f15,
+	0x1f18, 0x1f1d,
+	0x1f20, 0x1f45,
+	0x1f48, 0x1f4d,
+	0x1f50, 0x1f57,
+	0x1f59, 0x1f59,
+	0x1f5b, 0x1f5b,
+	0x1f5d, 0x1f5d,
+	0x1f5f, 0x1f7d,
+	0x1f80, 0x1fb4,
+	0x1fb6, 0x1fc4,
+	0x1fc6, 0x1fd3,
+	0x1fd6, 0x1fdb,
+	0x1fdd, 0x1fef,
+	0x1ff2, 0x1ff4,
+	0x1ff6, 0x1ffe,
+	0x2000, 0x2064,
+	0x2066, 0x2071,
+	0x2074, 0x208e,
+	0x2090, 0x209c,
+	0x20a0, 0x20c0,
+	0x20d0, 0x20f0,
+	0x2100, 0x218b,
+	0x2190, 0x2426,
+	0x2440, 0x244a,
+	0x2460, 0x2b73,
+	0x2b76, 0x2b95,
+	0x2b97, 0x2cf3,
+	0x2cf9, 0x2d25,
+	0x2d27, 0x2d27,
+	0x2d2d, 0x2d2d,
+	0x2d30, 0x2d67,
+	0x2d6f, 0x2d70,
+	0x2d7f, 0x2d96,
+	0x2da0, 0x2da6,
+	0x2da8, 0x2dae,
+	0x2db0, 0x2db6,
+	0x2db8, 0x2dbe,
+	0x2dc0, 0x2dc6,
+	0x2dc8, 0x2dce,
+	0x2dd0, 0x2dd6,
+	0x2dd8, 0x2dde,
+	0x2de0, 0x2e5d,
+	0x2e80, 0x2e99,
+	0x2e9b, 0x2ef3,
+	0x2f00, 0x2fd5,
+	0x2ff0, 0x2ffb,
+	0x3000, 0x303f,
+	0x3041, 0x3096,
+	0x3099, 0x30ff,
+	0x3105, 0x312f,
+	0x3131, 0x318e,
+	0x3190, 0x31e3,
+	0x31f0, 0x321e,
+	0x3220, 0xa48c,
+	0xa490, 0xa4c6,
+	0xa4d0, 0xa62b,
+	0xa640, 0xa6f7,
+	0xa700, 0xa7ca,
+	0xa7d0, 0xa7d1,
+	0xa7d3, 0xa7d3,
+	0xa7d5, 0xa7d9,
+	0xa7f2, 0xa82c,
+	0xa830, 0xa839,
+	0xa840, 0xa877,
+	0xa880, 0xa8c5,
+	0xa8ce, 0xa8d9,
+	0xa8e0, 0xa953,
+	0xa95f, 0xa97c,
+	0xa980, 0xa9cd,
+	0xa9cf, 0xa9d9,
+	0xa9de, 0xa9fe,
+	0xaa00, 0xaa36,
+	0xaa40, 0xaa4d,
+	0xaa50, 0xaa59,
+	0xaa5c, 0xaac2,
+	0xaadb, 0xaaf6,
+	0xab01, 0xab06,
+	0xab09, 0xab0e,
+	0xab11, 0xab16,
+	0xab20, 0xab26,
+	0xab28, 0xab2e,
+	0xab30, 0xab6b,
+	0xab70, 0xabed,
+	0xabf0, 0xabf9,
+	0xac00, 0xd7a3,
+	0xd7b0, 0xd7c6,
+	0xd7cb, 0xd7fb,
+	0xd800, 0xfa6d,
+	0xfa70, 0xfad9,
+	0xfb00, 0xfb06,
+	0xfb13, 0xfb17,
+	0xfb1d, 0xfb36,
+	0xfb38, 0xfb3c,
+	0xfb3e, 0xfb3e,
+	0xfb40, 0xfb41,
+	0xfb43, 0xfb44,
+	0xfb46, 0xfbc2,
+	0xfbd3, 0xfd8f,
+	0xfd92, 0xfdc7,
+	0xfdcf, 0xfe19,
+	0xfe20, 0xfe52,
+	0xfe54, 0xfe66,
+	0xfe68, 0xfe6b,
+	0xfe70, 0xfe74,
+	0xfe76, 0xfefc,
+	0xfeff, 0xfeff,
+	0xff01, 0xffbe,
+	0xffc2, 0xffc7,
+	0xffca, 0xffcf,
+	0xffd2, 0xffd7,
+	0xffda, 0xffdc,
+	0xffe0, 0xffe6,
+	0xffe8, 0xffee,
+	0xfff9, 0x1000b,
+	0x1000d, 0x10026,
+	0x10028, 0x1003a,
+	0x1003c, 0x1003d,
+	0x1003f, 0x1004d,
+	0x10050, 0x1005d,
+	0x10080, 0x100fa,
+	0x10100, 0x10102,
+	0x10107, 0x10133,
+	0x10137, 0x1018e,
+	0x10190, 0x1019c,
+	0x101a0, 0x101a0,
+	0x101d0, 0x101fd,
+	0x10280, 0x1029c,
+	0x102a0, 0x102d0,
+	0x102e0, 0x102fb,
+	0x10300, 0x10323,
+	0x1032d, 0x1034a,
+	0x10350, 0x1037a,
+	0x10380, 0x1039d,
+	0x1039f, 0x103c3,
+	0x103c8, 0x103d5,
+	0x10400, 0x1049d,
+	0x104a0, 0x104a9,
+	0x104b0, 0x104d3,
+	0x104d8, 0x104fb,
+	0x10500, 0x10527,
+	0x10530, 0x10563,
+	0x1056f, 0x1057a,
+	0x1057c, 0x1058a,
+	0x1058c, 0x10592,
+	0x10594, 0x10595,
+	0x10597, 0x105a1,
+	0x105a3, 0x105b1,
+	0x105b3, 0x105b9,
+	0x105bb, 0x105bc,
+	0x10600, 0x10736,
+	0x10740, 0x10755,
+	0x10760, 0x10767,
+	0x10780, 0x10785,
+	0x10787, 0x107b0,
+	0x107b2, 0x107ba,
+	0x10800, 0x10805,
+	0x10808, 0x10808,
+	0x1080a, 0x10835,
+	0x10837, 0x10838,
+	0x1083c, 0x1083c,
+	0x1083f, 0x10855,
+	0x10857, 0x1089e,
+	0x108a7, 0x108af,
+	0x108e0, 0x108f2,
+	0x108f4, 0x108f5,
+	0x108fb, 0x1091b,
+	0x1091f, 0x10939,
+	0x1093f, 0x1093f,
+	0x10980, 0x109b7,
+	0x109bc, 0x109cf,
+	0x109d2, 0x10a03,
+	0x10a05, 0x10a06,
+	0x10a0c, 0x10a13,
+	0x10a15, 0x10a17,
+	0x10a19, 0x10a35,
+	0x10a38, 0x10a3a,
+	0x10a3f, 0x10a48,
+	0x10a50, 0x10a58,
+	0x10a60, 0x10a9f,
+	0x10ac0, 0x10ae6,
+	0x10aeb, 0x10af6,
+	0x10b00, 0x10b35,
+	0x10b39, 0x10b55,
+	0x10b58, 0x10b72,
+	0x10b78, 0x10b91,
+	0x10b99, 0x10b9c,
+	0x10ba9, 0x10baf,
+	0x10c00, 0x10c48,
+	0x10c80, 0x10cb2,
+	0x10cc0, 0x10cf2,
+	0x10cfa, 0x10d27,
+	0x10d30, 0x10d39,
+	0x10e60, 0x10e7e,
+	0x10e80, 0x10ea9,
+	0x10eab, 0x10ead,
+	0x10eb0, 0x10eb1,
+	0x10efd, 0x10f27,
+	0x10f30, 0x10f59,
+	0x10f70, 0x10f89,
+	0x10fb0, 0x10fcb,
+	0x10fe0, 0x10ff6,
+	0x11000, 0x1104d,
+	0x11052, 0x11075,
+	0x1107f, 0x110c2,
+	0x110cd, 0x110cd,
+	0x110d0, 0x110e8,
+	0x110f0, 0x110f9,
+	0x11100, 0x11134,
+	0x11136, 0x11147,
+	0x11150, 0x11176,
+	0x11180, 0x111df,
+	0x111e1, 0x111f4,
+	0x11200, 0x11211,
+	0x11213, 0x11241,
+	0x11280, 0x11286,
+	0x11288, 0x11288,
+	0x1128a, 0x1128d,
+	0x1128f, 0x1129d,
+	0x1129f, 0x112a9,
+	0x112b0, 0x112ea,
+	0x112f0, 0x112f9,
+	0x11300, 0x11303,
+	0x11305, 0x1130c,
+	0x1130f, 0x11310,
+	0x11313, 0x11328,
+	0x1132a, 0x11330,
+	0x11332, 0x11333,
+	0x11335, 0x11339,
+	0x1133b, 0x11344,
+	0x11347, 0x11348,
+	0x1134b, 0x1134d,
+	0x11350, 0x11350,
+	0x11357, 0x11357,
+	0x1135d, 0x11363,
+	0x11366, 0x1136c,
+	0x11370, 0x11374,
+	0x11400, 0x1145b,
+	0x1145d, 0x11461,
+	0x11480, 0x114c7,
+	0x114d0, 0x114d9,
+	0x11580, 0x115b5,
+	0x115b8, 0x115dd,
+	0x11600, 0x11644,
+	0x11650, 0x11659,
+	0x11660, 0x1166c,
+	0x11680, 0x116b9,
+	0x116c0, 0x116c9,
+	0x11700, 0x1171a,
+	0x1171d, 0x1172b,
+	0x11730, 0x11746,
+	0x11800, 0x1183b,
+	0x118a0, 0x118f2,
+	0x118ff, 0x11906,
+	0x11909, 0x11909,
+	0x1190c, 0x11913,
+	0x11915, 0x11916,
+	0x11918, 0x11935,
+	0x11937, 0x11938,
+	0x1193b, 0x11946,
+	0x11950, 0x11959,
+	0x119a0, 0x119a7,
+	0x119aa, 0x119d7,
+	0x119da, 0x119e4,
+	0x11a00, 0x11a47,
+	0x11a50, 0x11aa2,
+	0x11ab0, 0x11af8,
+	0x11b00, 0x11b09,
+	0x11c00, 0x11c08,
+	0x11c0a, 0x11c36,
+	0x11c38, 0x11c45,
+	0x11c50, 0x11c6c,
+	0x11c70, 0x11c8f,
+	0x11c92, 0x11ca7,
+	0x11ca9, 0x11cb6,
+	0x11d00, 0x11d06,
+	0x11d08, 0x11d09,
+	0x11d0b, 0x11d36,
+	0x11d3a, 0x11d3a,
+	0x11d3c, 0x11d3d,
+	0x11d3f, 0x11d47,
+	0x11d50, 0x11d59,
+	0x11d60, 0x11d65,
+	0x11d67, 0x11d68,
+	0x11d6a, 0x11d8e,
+	0x11d90, 0x11d91,
+	0x11d93, 0x11d98,
+	0x11da0, 0x11da9,
+	0x11ee0, 0x11ef8,
+	0x11f00, 0x11f10,
+	0x11f12, 0x11f3a,
+	0x11f3e, 0x11f59,
+	0x11fb0, 0x11fb0,
+	0x11fc0, 0x11ff1,
+	0x11fff, 0x12399,
+	0x12400, 0x1246e,
+	0x12470, 0x12474,
+	0x12480, 0x12543,
+	0x12f90, 0x12ff2,
+	0x13000, 0x13455,
+	0x14400, 0x14646,
+	0x16800, 0x16a38,
+	0x16a40, 0x16a5e,
+	0x16a60, 0x16a69,
+	0x16a6e, 0x16abe,
+	0x16ac0, 0x16ac9,
+	0x16ad0, 0x16aed,
+	0x16af0, 0x16af5,
+	0x16b00, 0x16b45,
+	0x16b50, 0x16b59,
+	0x16b5b, 0x16b61,
+	0x16b63, 0x16b77,
+	0x16b7d, 0x16b8f,
+	0x16e40, 0x16e9a,
+	0x16f00, 0x16f4a,
+	0x16f4f, 0x16f87,
+	0x16f8f, 0x16f9f,
+	0x16fe0, 0x16fe4,
+	0x16ff0, 0x16ff1,
+	0x17000, 0x187f7,
+	0x18800, 0x18cd5,
+	0x18d00, 0x18d08,
+	0x1aff0, 0x1aff3,
+	0x1aff5, 0x1affb,
+	0x1affd, 0x1affe,
+	0x1b000, 0x1b122,
+	0x1b132, 0x1b132,
+	0x1b150, 0x1b152,
+	0x1b155, 0x1b155,
+	0x1b164, 0x1b167,
+	0x1b170, 0x1b2fb,
+	0x1bc00, 0x1bc6a,
+	0x1bc70, 0x1bc7c,
+	0x1bc80, 0x1bc88,
+	0x1bc90, 0x1bc99,
+	0x1bc9c, 0x1bca3,
+	0x1cf00, 0x1cf2d,
+	0x1cf30, 0x1cf46,
+	0x1cf50, 0x1cfc3,
+	0x1d000, 0x1d0f5,
+	0x1d100, 0x1d126,
+	0x1d129, 0x1d1ea,
+	0x1d200, 0x1d245,
+	0x1d2c0, 0x1d2d3,
+	0x1d2e0, 0x1d2f3,
+	0x1d300, 0x1d356,
+	0x1d360, 0x1d378,
+	0x1d400, 0x1d454,
+	0x1d456, 0x1d49c,
+	0x1d49e, 0x1d49f,
+	0x1d4a2, 0x1d4a2,
+	0x1d4a5, 0x1d4a6,
+	0x1d4a9, 0x1d4ac,
+	0x1d4ae, 0x1d4b9,
+	0x1d4bb, 0x1d4bb,
+	0x1d4bd, 0x1d4c3,
+	0x1d4c5, 0x1d505,
+	0x1d507, 0x1d50a,
+	0x1d50d, 0x1d514,
+	0x1d516, 0x1d51c,
+	0x1d51e, 0x1d539,
+	0x1d53b, 0x1d53e,
+	0x1d540, 0x1d544,
+	0x1d546, 0x1d546,
+	0x1d54a, 0x1d550,
+	0x1d552, 0x1d6a5,
+	0x1d6a8, 0x1d7cb,
+	0x1d7ce, 0x1da8b,
+	0x1da9b, 0x1da9f,
+	0x1daa1, 0x1daaf,
+	0x1df00, 0x1df1e,
+	0x1df25, 0x1df2a,
+	0x1e000, 0x1e006,
+	0x1e008, 0x1e018,
+	0x1e01b, 0x1e021,
+	0x1e023, 0x1e024,
+	0x1e026, 0x1e02a,
+	0x1e030, 0x1e06d,
+	0x1e08f, 0x1e08f,
+	0x1e100, 0x1e12c,
+	0x1e130, 0x1e13d,
+	0x1e140, 0x1e149,
+	0x1e14e, 0x1e14f,
+	0x1e290, 0x1e2ae,
+	0x1e2c0, 0x1e2f9,
+	0x1e2ff, 0x1e2ff,
+	0x1e4d0, 0x1e4f9,
+	0x1e7e0, 0x1e7e6,
+	0x1e7e8, 0x1e7eb,
+	0x1e7ed, 0x1e7ee,
+	0x1e7f0, 0x1e7fe,
+	0x1e800, 0x1e8c4,
+	0x1e8c7, 0x1e8d6,
+	0x1e900, 0x1e94b,
+	0x1e950, 0x1e959,
+	0x1e95e, 0x1e95f,
+	0x1ec71, 0x1ecb4,
+	0x1ed01, 0x1ed3d,
+	0x1ee00, 0x1ee03,
+	0x1ee05, 0x1ee1f,
+	0x1ee21, 0x1ee22,
+	0x1ee24, 0x1ee24,
+	0x1ee27, 0x1ee27,
+	0x1ee29, 0x1ee32,
+	0x1ee34, 0x1ee37,
+	0x1ee39, 0x1ee39,
+	0x1ee3b, 0x1ee3b,
+	0x1ee42, 0x1ee42,
+	0x1ee47, 0x1ee47,
+	0x1ee49, 0x1ee49,
+	0x1ee4b, 0x1ee4b,
+	0x1ee4d, 0x1ee4f,
+	0x1ee51, 0x1ee52,
+	0x1ee54, 0x1ee54,
+	0x1ee57, 0x1ee57,
+	0x1ee59, 0x1ee59,
+	0x1ee5b, 0x1ee5b,
+	0x1ee5d, 0x1ee5d,
+	0x1ee5f, 0x1ee5f,
+	0x1ee61, 0x1ee62,
+	0x1ee64, 0x1ee64,
+	0x1ee67, 0x1ee6a,
+	0x1ee6c, 0x1ee72,
+	0x1ee74, 0x1ee77,
+	0x1ee79, 0x1ee7c,
+	0x1ee7e, 0x1ee7e,
+	0x1ee80, 0x1ee89,
+	0x1ee8b, 0x1ee9b,
+	0x1eea1, 0x1eea3,
+	0x1eea5, 0x1eea9,
+	0x1eeab, 0x1eebb,
+	0x1eef0, 0x1eef1,
+	0x1f000, 0x1f02b,
+	0x1f030, 0x1f093,
+	0x1f0a0, 0x1f0ae,
+	0x1f0b1, 0x1f0bf,
+	0x1f0c1, 0x1f0cf,
+	0x1f0d1, 0x1f0f5,
+	0x1f100, 0x1f1ad,
+	0x1f1e6, 0x1f202,
+	0x1f210, 0x1f23b,
+	0x1f240, 0x1f248,
+	0x1f250, 0x1f251,
+	0x1f260, 0x1f265,
+	0x1f300, 0x1f6d7,
+	0x1f6dc, 0x1f6ec,
+	0x1f6f0, 0x1f6fc,
+	0x1f700, 0x1f776,
+	0x1f77b, 0x1f7d9,
+	0x1f7e0, 0x1f7eb,
+	0x1f7f0, 0x1f7f0,
+	0x1f800, 0x1f80b,
+	0x1f810, 0x1f847,
+	0x1f850, 0x1f859,
+	0x1f860, 0x1f887,
+	0x1f890, 0x1f8ad,
+	0x1f8b0, 0x1f8b1,
+	0x1f900, 0x1fa53,
+	0x1fa60, 0x1fa6d,
+	0x1fa70, 0x1fa7c,
+	0x1fa80, 0x1fa88,
+	0x1fa90, 0x1fabd,
+	0x1fabf, 0x1fac5,
+	0x1face, 0x1fadb,
+	0x1fae0, 0x1fae8,
+	0x1faf0, 0x1faf8,
+	0x1fb00, 0x1fb92,
+	0x1fb94, 0x1fbca,
+	0x1fbf0, 0x1fbf9,
+	0x1fffe, 0x2a6df,
+	0x2a700, 0x2b739,
+	0x2b740, 0x2b81d,
+	0x2b820, 0x2cea1,
+	0x2ceb0, 0x2ebe0,
+	0x2f800, 0x2fa1d,
+	0x2fffe, 0x3134a,
+	0x31350, 0x323af,
+	0x3fffe, 0x3ffff,
+	0x4fffe, 0x4ffff,
+	0x5fffe, 0x5ffff,
+	0x6fffe, 0x6ffff,
+	0x7fffe, 0x7ffff,
+	0x8fffe, 0x8ffff,
+	0x9fffe, 0x9ffff,
+	0xafffe, 0xaffff,
+	0xbfffe, 0xbffff,
+	0xcfffe, 0xcffff,
+	0xdfffe, 0xdffff,
+	0xe0001, 0xe0001,
+	0xe0020, 0xe007f,
+	0xe0100, 0xe01ef,
+	0xefffe, 0x10ffff,
+}; /* CR_Age_15_0 */
+
 #endif /* USE_UNICODE_AGE_PROPERTIES */
 /* 'Grapheme_Cluster_Break_Prepend': Grapheme_Cluster_Break=Prepend */
 static const OnigCodePoint CR_Grapheme_Cluster_Break_Prepend[] = {
-	14,
+	15,
 	0x0600, 0x0605,
 	0x06dd, 0x06dd,
 	0x070f, 0x070f,
@@ -36650,6 +37652,7 @@ static const OnigCodePoint CR_Grapheme_Cluster_Break_Prepend[] = {
 	0x11a3a, 0x11a3a,
 	0x11a84, 0x11a89,
 	0x11d46, 0x11d46,
+	0x11f02, 0x11f02,
 }; /* CR_Grapheme_Cluster_Break_Prepend */
 
 /* 'Grapheme_Cluster_Break_CR': Grapheme_Cluster_Break=CR */
@@ -36677,7 +37680,7 @@ static const OnigCodePoint CR_Grapheme_Cluster_Break_Control[] = {
 	0x2060, 0x206f,
 	0xfeff, 0xfeff,
 	0xfff0, 0xfffb,
-	0x13430, 0x13438,
+	0x13430, 0x1343f,
 	0x1bca0, 0x1bca3,
 	0x1d173, 0x1d17a,
 	0xe0000, 0xe001f,
@@ -36687,7 +37690,7 @@ static const OnigCodePoint CR_Grapheme_Cluster_Break_Control[] = {
 
 /* 'Grapheme_Cluster_Break_Extend': Grapheme_Cluster_Break=Extend */
 static const OnigCodePoint CR_Grapheme_Cluster_Break_Extend[] = {
-	354,
+	364,
 	0x0300, 0x036f,
 	0x0483, 0x0489,
 	0x0591, 0x05bd,
@@ -36790,7 +37793,7 @@ static const OnigCodePoint CR_Grapheme_Cluster_Break_Extend[] = {
 	0x0e47, 0x0e4e,
 	0x0eb1, 0x0eb1,
 	0x0eb4, 0x0ebc,
-	0x0ec8, 0x0ecd,
+	0x0ec8, 0x0ece,
 	0x0f18, 0x0f19,
 	0x0f35, 0x0f35,
 	0x0f37, 0x0f37,
@@ -36919,6 +37922,7 @@ static const OnigCodePoint CR_Grapheme_Cluster_Break_Extend[] = {
 	0x10ae5, 0x10ae6,
 	0x10d24, 0x10d27,
 	0x10eab, 0x10eac,
+	0x10efd, 0x10eff,
 	0x10f46, 0x10f50,
 	0x10f82, 0x10f85,
 	0x11001, 0x11001,
@@ -36941,6 +37945,7 @@ static const OnigCodePoint CR_Grapheme_Cluster_Break_Extend[] = {
 	0x11234, 0x11234,
 	0x11236, 0x11237,
 	0x1123e, 0x1123e,
+	0x11241, 0x11241,
 	0x112df, 0x112df,
 	0x112e3, 0x112ea,
 	0x11300, 0x11301,
@@ -37008,6 +38013,12 @@ static const OnigCodePoint CR_Grapheme_Cluster_Break_Extend[] = {
 	0x11d95, 0x11d95,
 	0x11d97, 0x11d97,
 	0x11ef3, 0x11ef4,
+	0x11f00, 0x11f01,
+	0x11f36, 0x11f3a,
+	0x11f40, 0x11f40,
+	0x11f42, 0x11f42,
+	0x13440, 0x13440,
+	0x13447, 0x13455,
 	0x16af0, 0x16af4,
 	0x16b30, 0x16b36,
 	0x16f4f, 0x16f4f,
@@ -37034,9 +38045,11 @@ static const OnigCodePoint CR_Grapheme_Cluster_Break_Extend[] = {
 	0x1e01b, 0x1e021,
 	0x1e023, 0x1e024,
 	0x1e026, 0x1e02a,
+	0x1e08f, 0x1e08f,
 	0x1e130, 0x1e136,
 	0x1e2ae, 0x1e2ae,
 	0x1e2ec, 0x1e2ef,
+	0x1e4ec, 0x1e4ef,
 	0x1e8d0, 0x1e8d6,
 	0x1e944, 0x1e94a,
 	0x1f3fb, 0x1f3ff,
@@ -37049,7 +38062,7 @@ static const OnigCodePoint CR_Grapheme_Cluster_Break_Extend[] = {
 
 /* 'Grapheme_Cluster_Break_SpacingMark': Grapheme_Cluster_Break=SpacingMark */
 static const OnigCodePoint CR_Grapheme_Cluster_Break_SpacingMark[] = {
-	161,
+	165,
 	0x0903, 0x0903,
 	0x093b, 0x093b,
 	0x093e, 0x0940,
@@ -37081,6 +38094,7 @@ static const OnigCodePoint CR_Grapheme_Cluster_Break_SpacingMark[] = {
 	0x0cc3, 0x0cc4,
 	0x0cc7, 0x0cc8,
 	0x0cca, 0x0ccb,
+	0x0cf3, 0x0cf3,
 	0x0d02, 0x0d03,
 	0x0d3f, 0x0d40,
 	0x0d46, 0x0d48,
@@ -37183,7 +38197,6 @@ static const OnigCodePoint CR_Grapheme_Cluster_Break_SpacingMark[] = {
 	0x116ac, 0x116ac,
 	0x116ae, 0x116af,
 	0x116b6, 0x116b6,
-	0x11720, 0x11721,
 	0x11726, 0x11726,
 	0x1182c, 0x1182e,
 	0x11838, 0x11838,
@@ -37207,6 +38220,10 @@ static const OnigCodePoint CR_Grapheme_Cluster_Break_SpacingMark[] = {
 	0x11d93, 0x11d94,
 	0x11d96, 0x11d96,
 	0x11ef5, 0x11ef6,
+	0x11f03, 0x11f03,
+	0x11f34, 0x11f35,
+	0x11f3e, 0x11f3f,
+	0x11f41, 0x11f41,
 	0x16f51, 0x16f87,
 	0x16ff0, 0x16ff1,
 	0x1d166, 0x1d166,
@@ -39275,6 +40292,12 @@ static const OnigCodePoint CR_In_Yezidi[] = {
 	0x10e80, 0x10ebf,
 }; /* CR_In_Yezidi */
 
+/* 'In_Arabic_Extended_C': Block */
+static const OnigCodePoint CR_In_Arabic_Extended_C[] = {
+	1,
+	0x10ec0, 0x10eff,
+}; /* CR_In_Arabic_Extended_C */
+
 /* 'In_Old_Sogdian': Block */
 static const OnigCodePoint CR_In_Old_Sogdian[] = {
 	1,
@@ -39458,6 +40481,12 @@ static const OnigCodePoint CR_In_Pau_Cin_Hau[] = {
 	0x11ac0, 0x11aff,
 }; /* CR_In_Pau_Cin_Hau */
 
+/* 'In_Devanagari_Extended_A': Block */
+static const OnigCodePoint CR_In_Devanagari_Extended_A[] = {
+	1,
+	0x11b00, 0x11b5f,
+}; /* CR_In_Devanagari_Extended_A */
+
 /* 'In_Bhaiksuki': Block */
 static const OnigCodePoint CR_In_Bhaiksuki[] = {
 	1,
@@ -39488,6 +40517,12 @@ static const OnigCodePoint CR_In_Makasar[] = {
 	0x11ee0, 0x11eff,
 }; /* CR_In_Makasar */
 
+/* 'In_Kawi': Block */
+static const OnigCodePoint CR_In_Kawi[] = {
+	1,
+	0x11f00, 0x11f5f,
+}; /* CR_In_Kawi */
+
 /* 'In_Lisu_Supplement': Block */
 static const OnigCodePoint CR_In_Lisu_Supplement[] = {
 	1,
@@ -39533,7 +40568,7 @@ static const OnigCodePoint CR_In_Egyptian_Hieroglyphs[] = {
 /* 'In_Egyptian_Hieroglyph_Format_Controls': Block */
 static const OnigCodePoint CR_In_Egyptian_Hieroglyph_Format_Controls[] = {
 	1,
-	0x13430, 0x1343f,
+	0x13430, 0x1345f,
 }; /* CR_In_Egyptian_Hieroglyph_Format_Controls */
 
 /* 'In_Anatolian_Hieroglyphs': Block */
@@ -39680,6 +40715,12 @@ static const OnigCodePoint CR_In_Ancient_Greek_Musical_Notation[] = {
 	0x1d200, 0x1d24f,
 }; /* CR_In_Ancient_Greek_Musical_Notation */
 
+/* 'In_Kaktovik_Numerals': Block */
+static const OnigCodePoint CR_In_Kaktovik_Numerals[] = {
+	1,
+	0x1d2c0, 0x1d2df,
+}; /* CR_In_Kaktovik_Numerals */
+
 /* 'In_Mayan_Numerals': Block */
 static const OnigCodePoint CR_In_Mayan_Numerals[] = {
 	1,
@@ -39722,6 +40763,12 @@ static const OnigCodePoint CR_In_Glagolitic_Supplement[] = {
 	0x1e000, 0x1e02f,
 }; /* CR_In_Glagolitic_Supplement */
 
+/* 'In_Cyrillic_Extended_D': Block */
+static const OnigCodePoint CR_In_Cyrillic_Extended_D[] = {
+	1,
+	0x1e030, 0x1e08f,
+}; /* CR_In_Cyrillic_Extended_D */
+
 /* 'In_Nyiakeng_Puachue_Hmong': Block */
 static const OnigCodePoint CR_In_Nyiakeng_Puachue_Hmong[] = {
 	1,
@@ -39740,6 +40787,12 @@ static const OnigCodePoint CR_In_Wancho[] = {
 	0x1e2c0, 0x1e2ff,
 }; /* CR_In_Wancho */
 
+/* 'In_Nag_Mundari': Block */
+static const OnigCodePoint CR_In_Nag_Mundari[] = {
+	1,
+	0x1e4d0, 0x1e4ff,
+}; /* CR_In_Nag_Mundari */
+
 /* 'In_Ethiopic_Extended_B': Block */
 static const OnigCodePoint CR_In_Ethiopic_Extended_B[] = {
 	1,
@@ -39914,6 +40967,12 @@ static const OnigCodePoint CR_In_CJK_Unified_Ideographs_Extension_G[] = {
 	0x30000, 0x3134f,
 }; /* CR_In_CJK_Unified_Ideographs_Extension_G */
 
+/* 'In_CJK_Unified_Ideographs_Extension_H': Block */
+static const OnigCodePoint CR_In_CJK_Unified_Ideographs_Extension_H[] = {
+	1,
+	0x31350, 0x323af,
+}; /* CR_In_CJK_Unified_Ideographs_Extension_H */
+
 /* 'In_Tags': Block */
 static const OnigCodePoint CR_In_Tags[] = {
 	1,
@@ -39952,7 +41011,6 @@ static const OnigCodePoint CR_In_No_Block[] = {
 	0x10bb0, 0x10bff,
 	0x10c50, 0x10c7f,
 	0x10d40, 0x10e5f,
-	0x10ec0, 0x10eff,
 	0x11250, 0x1127f,
 	0x11380, 0x113ff,
 	0x114e0, 0x1157f,
@@ -39960,12 +41018,12 @@ static const OnigCodePoint CR_In_No_Block[] = {
 	0x11750, 0x117ff,
 	0x11850, 0x1189f,
 	0x11960, 0x1199f,
-	0x11b00, 0x11bff,
+	0x11b60, 0x11bff,
 	0x11cc0, 0x11cff,
 	0x11db0, 0x11edf,
-	0x11f00, 0x11faf,
+	0x11f60, 0x11faf,
 	0x12550, 0x12f8f,
-	0x13440, 0x143ff,
+	0x13460, 0x143ff,
 	0x14680, 0x167ff,
 	0x16b90, 0x16e3f,
 	0x16ea0, 0x16eff,
@@ -39974,12 +41032,13 @@ static const OnigCodePoint CR_In_No_Block[] = {
 	0x1b300, 0x1bbff,
 	0x1bcb0, 0x1ceff,
 	0x1cfd0, 0x1cfff,
-	0x1d250, 0x1d2df,
+	0x1d250, 0x1d2bf,
 	0x1d380, 0x1d3ff,
 	0x1dab0, 0x1deff,
-	0x1e030, 0x1e0ff,
+	0x1e090, 0x1e0ff,
 	0x1e150, 0x1e28f,
-	0x1e300, 0x1e7df,
+	0x1e300, 0x1e4cf,
+	0x1e500, 0x1e7df,
 	0x1e8e0, 0x1e8ff,
 	0x1e960, 0x1ec6f,
 	0x1ecc0, 0x1ecff,
@@ -39989,7 +41048,7 @@ static const OnigCodePoint CR_In_No_Block[] = {
 	0x2a6e0, 0x2a6ff,
 	0x2ebf0, 0x2f7ff,
 	0x2fa20, 0x2ffff,
-	0x31350, 0xdffff,
+	0x323b0, 0xdffff,
 	0xe0080, 0xe00ff,
 	0xe01f0, 0xeffff,
 }; /* CR_In_No_Block */
@@ -40233,6 +41292,8 @@ static const OnigCodePoint* const CodeRanges[] = {
   CR_Tangsa,
   CR_Toto,
   CR_Vithkuqi,
+  CR_Kawi,
+  CR_Nag_Mundari,
   CR_White_Space,
   CR_Bidi_Control,
   CR_Join_Control,
@@ -40299,6 +41360,7 @@ static const OnigCodePoint* const CodeRanges[] = {
   CR_Age_12_1,
   CR_Age_13_0,
   CR_Age_14_0,
+  CR_Age_15_0,
 #endif /* USE_UNICODE_AGE_PROPERTIES */
   CR_Grapheme_Cluster_Break_Prepend,
   CR_Grapheme_Cluster_Break_CR,
@@ -40522,6 +41584,7 @@ static const OnigCodePoint* const CodeRanges[] = {
   CR_In_Hanifi_Rohingya,
   CR_In_Rumi_Numeral_Symbols,
   CR_In_Yezidi,
+  CR_In_Arabic_Extended_C,
   CR_In_Old_Sogdian,
   CR_In_Sogdian,
   CR_In_Old_Uyghur,
@@ -40553,11 +41616,13 @@ static const OnigCodePoint* const CodeRanges[] = {
   CR_In_Soyombo,
   CR_In_Unified_Canadian_Aboriginal_Syllabics_Extended_A,
   CR_In_Pau_Cin_Hau,
+  CR_In_Devanagari_Extended_A,
   CR_In_Bhaiksuki,
   CR_In_Marchen,
   CR_In_Masaram_Gondi,
   CR_In_Gunjala_Gondi,
   CR_In_Makasar,
+  CR_In_Kawi,
   CR_In_Lisu_Supplement,
   CR_In_Tamil_Supplement,
   CR_In_Cuneiform,
@@ -40590,6 +41655,7 @@ static const OnigCodePoint* const CodeRanges[] = {
   CR_In_Byzantine_Musical_Symbols,
   CR_In_Musical_Symbols,
   CR_In_Ancient_Greek_Musical_Notation,
+  CR_In_Kaktovik_Numerals,
   CR_In_Mayan_Numerals,
   CR_In_Tai_Xuan_Jing_Symbols,
   CR_In_Counting_Rod_Numerals,
@@ -40597,9 +41663,11 @@ static const OnigCodePoint* const CodeRanges[] = {
   CR_In_Sutton_SignWriting,
   CR_In_Latin_Extended_G,
   CR_In_Glagolitic_Supplement,
+  CR_In_Cyrillic_Extended_D,
   CR_In_Nyiakeng_Puachue_Hmong,
   CR_In_Toto,
   CR_In_Wancho,
+  CR_In_Nag_Mundari,
   CR_In_Ethiopic_Extended_B,
   CR_In_Mende_Kikakui,
   CR_In_Adlam,
@@ -40629,6 +41697,7 @@ static const OnigCodePoint* const CodeRanges[] = {
   CR_In_CJK_Unified_Ideographs_Extension_F,
   CR_In_CJK_Compatibility_Ideographs_Supplement,
   CR_In_CJK_Unified_Ideographs_Extension_G,
+  CR_In_CJK_Unified_Ideographs_Extension_H,
   CR_In_Tags,
   CR_In_Variation_Selectors_Supplement,
   CR_In_Supplementary_Private_Use_Area_A,
@@ -40642,11 +41711,7 @@ struct uniname2ctype_struct {
 };
 #define uniname2ctype_offset(str) offsetof(struct uniname2ctype_pool_t, uniname2ctype_pool_##str)
 
-static const struct uniname2ctype_struct *uniname2ctype_p(
-#if !(1+0) /* if ANSI, old style not to conflict with generated prototype */
-    const char *, unsigned int
-#endif
-);
+static const struct uniname2ctype_struct *uniname2ctype_p(register const char *str, register size_t len);
 
 #ifndef USE_UNICODE_PROPERTIES
 #define TOTAL_KEYWORDS 15
@@ -40657,9 +41722,9 @@ static const struct uniname2ctype_struct *uniname2ctype_p(
 /* maximum key range = 15, duplicates = 0 */
 #else /* USE_UNICODE_PROPERTIES */
 #ifndef USE_UNICODE_AGE_PROPERTIES
-#define TOTAL_KEYWORDS 856
+#define TOTAL_KEYWORDS 866
 #else /* USE_UNICODE_AGE_PROPERTIES */
-#define TOTAL_KEYWORDS 880
+#define TOTAL_KEYWORDS 891
 #endif /* USE_UNICODE_AGE_PROPERTIES */
 #define MIN_WORD_LENGTH 1
 #define MAX_WORD_LENGTH 45
@@ -40708,13 +41773,13 @@ uniname2ctype_hash (register const char *str, register size_t len)
       6099, 6099, 6099, 6099, 6099, 6099, 6099, 6099, 6099, 6099,
 #else /* USE_UNICODE_AGE_PROPERTIES */
       6099, 6099, 6099, 6099, 6099, 6099,   12, 6099,    3,    1,
-         4,    8,   36,   24,   14,   16,   10,    7, 6099, 6099,
+         4,    8,   32,   26,   14,   17,   10,    7, 6099, 6099,
 #endif /* USE_UNICODE_AGE_PROPERTIES */
       6099, 6099, 6099, 6099, 6099, 6099, 6099, 6099, 6099, 6099,
       6099, 6099, 6099, 6099, 6099, 6099, 6099, 6099, 6099, 6099,
       6099, 6099, 6099, 6099, 6099, 6099, 6099, 6099, 6099, 6099,
       6099, 6099, 6099, 6099, 6099, 6099, 6099,    1, 1425,  113,
-       437,   37, 1086, 1071, 1051,    4, 1267,    9,  500,   88,
+       437,   37, 1086, 1071, 1051,    4, 1984,    9,  500,   88,
          8,   18, 1371, 1287,   54,  203,  310,  619, 1958,  603,
        275, 1624,   44,    1,   22, 6099, 6099, 6099, 6099, 6099
 #endif /* USE_UNICODE_PROPERTIES */
@@ -40944,6 +42009,7 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str636[sizeof("innewa")];
     char uniname2ctype_pool_str639[sizeof("sk")];
     char uniname2ctype_pool_str642[sizeof("control")];
+    char uniname2ctype_pool_str643[sizeof("inkawi")];
     char uniname2ctype_pool_str645[sizeof("inancientsymbols")];
     char uniname2ctype_pool_str647[sizeof("palm")];
     char uniname2ctype_pool_str650[sizeof("inlycian")];
@@ -40958,6 +42024,7 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str695[sizeof("inwarangciti")];
     char uniname2ctype_pool_str696[sizeof("sora")];
     char uniname2ctype_pool_str697[sizeof("inopticalcharacterrecognition")];
+    char uniname2ctype_pool_str700[sizeof("kawi")];
     char uniname2ctype_pool_str703[sizeof("inoldsogdian")];
     char uniname2ctype_pool_str705[sizeof("inmalayalam")];
     char uniname2ctype_pool_str707[sizeof("bamum")];
@@ -41078,11 +42145,13 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str1182[sizeof("inogham")];
     char uniname2ctype_pool_str1183[sizeof("cher")];
     char uniname2ctype_pool_str1185[sizeof("chakma")];
+    char uniname2ctype_pool_str1186[sizeof("inkaktoviknumerals")];
     char uniname2ctype_pool_str1190[sizeof("emoji")];
     char uniname2ctype_pool_str1191[sizeof("insiddham")];
     char uniname2ctype_pool_str1197[sizeof("cherokee")];
     char uniname2ctype_pool_str1198[sizeof("khar")];
     char uniname2ctype_pool_str1203[sizeof("inmongolian")];
+    char uniname2ctype_pool_str1204[sizeof("innagmundari")];
     char uniname2ctype_pool_str1207[sizeof("incherokeesupplement")];
     char uniname2ctype_pool_str1209[sizeof("manichaean")];
     char uniname2ctype_pool_str1212[sizeof("inolchiki")];
@@ -41126,48 +42195,46 @@ struct uniname2ctype_pool_t
 #ifdef USE_UNICODE_AGE_PROPERTIES
     char uniname2ctype_pool_str1257[sizeof("age=6.0")];
     char uniname2ctype_pool_str1258[sizeof("age=6.2")];
-    char uniname2ctype_pool_str1259[sizeof("age=7.0")];
+    char uniname2ctype_pool_str1259[sizeof("age=15.0")];
+    char uniname2ctype_pool_str1260[sizeof("age=7.0")];
     char uniname2ctype_pool_str1262[sizeof("age=6.3")];
 #endif /* USE_UNICODE_AGE_PROPERTIES */
     char uniname2ctype_pool_str1263[sizeof("cwt")];
 #ifdef USE_UNICODE_AGE_PROPERTIES
-    char uniname2ctype_pool_str1265[sizeof("age=5.1")];
+    char uniname2ctype_pool_str1265[sizeof("age=14.0")];
 #endif /* USE_UNICODE_AGE_PROPERTIES */
     char uniname2ctype_pool_str1266[sizeof("unassigned")];
 #ifdef USE_UNICODE_AGE_PROPERTIES
-    char uniname2ctype_pool_str1267[sizeof("age=5.0")];
-    char uniname2ctype_pool_str1268[sizeof("age=5.2")];
-    char uniname2ctype_pool_str1269[sizeof("age=14.0")];
+    char uniname2ctype_pool_str1267[sizeof("age=5.1")];
+    char uniname2ctype_pool_str1269[sizeof("age=5.0")];
+    char uniname2ctype_pool_str1270[sizeof("age=5.2")];
 #endif /* USE_UNICODE_AGE_PROPERTIES */
     char uniname2ctype_pool_str1271[sizeof("diacritic")];
+#ifdef USE_UNICODE_AGE_PROPERTIES
+    char uniname2ctype_pool_str1273[sizeof("age=4.1")];
+#endif /* USE_UNICODE_AGE_PROPERTIES */
     char uniname2ctype_pool_str1274[sizeof("ahom")];
 #ifdef USE_UNICODE_AGE_PROPERTIES
-    char uniname2ctype_pool_str1277[sizeof("age=4.1")];
-    char uniname2ctype_pool_str1279[sizeof("age=4.0")];
+    char uniname2ctype_pool_str1275[sizeof("age=4.0")];
 #endif /* USE_UNICODE_AGE_PROPERTIES */
     char uniname2ctype_pool_str1282[sizeof("incjkunifiedideographsextensione")];
-    char uniname2ctype_pool_str1284[sizeof("hani")];
     char uniname2ctype_pool_str1285[sizeof("khmr")];
-    char uniname2ctype_pool_str1287[sizeof("han")];
     char uniname2ctype_pool_str1289[sizeof("insinhala")];
     char uniname2ctype_pool_str1292[sizeof("inmiscellaneoustechnical")];
     char uniname2ctype_pool_str1297[sizeof("saur")];
-    char uniname2ctype_pool_str1298[sizeof("hano")];
     char uniname2ctype_pool_str1300[sizeof("guru")];
     char uniname2ctype_pool_str1301[sizeof("sundanese")];
     char uniname2ctype_pool_str1306[sizeof("punct")];
     char uniname2ctype_pool_str1314[sizeof("paucinhau")];
     char uniname2ctype_pool_str1317[sizeof("gurmukhi")];
-    char uniname2ctype_pool_str1323[sizeof("inkhojki")];
-    char uniname2ctype_pool_str1327[sizeof("hanunoo")];
     char uniname2ctype_pool_str1328[sizeof("chorasmian")];
-    char uniname2ctype_pool_str1330[sizeof("hira")];
     char uniname2ctype_pool_str1331[sizeof("logicalorderexception")];
     char uniname2ctype_pool_str1340[sizeof("khmer")];
     char uniname2ctype_pool_str1343[sizeof("limbu")];
     char uniname2ctype_pool_str1349[sizeof("chrs")];
     char uniname2ctype_pool_str1352[sizeof("oriya")];
     char uniname2ctype_pool_str1354[sizeof("inscriptionalpahlavi")];
+    char uniname2ctype_pool_str1356[sizeof("incyrillicextendedd")];
     char uniname2ctype_pool_str1358[sizeof("incjkunifiedideographsextensionc")];
     char uniname2ctype_pool_str1360[sizeof("cntrl")];
     char uniname2ctype_pool_str1365[sizeof("inlatinextendedadditional")];
@@ -41235,7 +42302,6 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str1587[sizeof("indogra")];
     char uniname2ctype_pool_str1597[sizeof("arab")];
     char uniname2ctype_pool_str1598[sizeof("medefaidrin")];
-    char uniname2ctype_pool_str1601[sizeof("hatran")];
     char uniname2ctype_pool_str1607[sizeof("inshorthandformatcontrols")];
     char uniname2ctype_pool_str1613[sizeof("phli")];
     char uniname2ctype_pool_str1617[sizeof("inimperialaramaic")];
@@ -41244,7 +42310,6 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str1623[sizeof("inanatolianhieroglyphs")];
     char uniname2ctype_pool_str1629[sizeof("punctuation")];
     char uniname2ctype_pool_str1635[sizeof("graphemeextend")];
-    char uniname2ctype_pool_str1636[sizeof("hatr")];
     char uniname2ctype_pool_str1643[sizeof("cwl")];
     char uniname2ctype_pool_str1644[sizeof("vith")];
     char uniname2ctype_pool_str1654[sizeof("ingeometricshapes")];
@@ -41302,7 +42367,6 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str1845[sizeof("oidc")];
     char uniname2ctype_pool_str1848[sizeof("bopo")];
     char uniname2ctype_pool_str1851[sizeof("cuneiform")];
-    char uniname2ctype_pool_str1857[sizeof("hex")];
     char uniname2ctype_pool_str1866[sizeof("caseignorable")];
     char uniname2ctype_pool_str1871[sizeof("inoldpersian")];
     char uniname2ctype_pool_str1881[sizeof("cwu")];
@@ -41321,10 +42385,8 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str1935[sizeof("oids")];
     char uniname2ctype_pool_str1936[sizeof("inarabicextendeda")];
     char uniname2ctype_pool_str1941[sizeof("modifierletter")];
-    char uniname2ctype_pool_str1948[sizeof("gujr")];
     char uniname2ctype_pool_str1950[sizeof("incjksymbolsandpunctuation")];
     char uniname2ctype_pool_str1956[sizeof("olower")];
-    char uniname2ctype_pool_str1957[sizeof("gujarati")];
     char uniname2ctype_pool_str1958[sizeof("bopomofo")];
     char uniname2ctype_pool_str1964[sizeof("inlisu")];
     char uniname2ctype_pool_str1967[sizeof("inoldpermic")];
@@ -41338,19 +42400,26 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str1993[sizeof("inbalinese")];
     char uniname2ctype_pool_str1994[sizeof("sorasompeng")];
     char uniname2ctype_pool_str1996[sizeof("closepunctuation")];
+    char uniname2ctype_pool_str2001[sizeof("hani")];
     char uniname2ctype_pool_str2002[sizeof("inmayannumerals")];
+    char uniname2ctype_pool_str2004[sizeof("han")];
     char uniname2ctype_pool_str2006[sizeof("inmiscellaneousmathematicalsymbolsb")];
     char uniname2ctype_pool_str2010[sizeof("inlepcha")];
     char uniname2ctype_pool_str2011[sizeof("patsyn")];
     char uniname2ctype_pool_str2012[sizeof("inlisusupplement")];
     char uniname2ctype_pool_str2014[sizeof("insyriacsupplement")];
+    char uniname2ctype_pool_str2015[sizeof("hano")];
     char uniname2ctype_pool_str2016[sizeof("newa")];
     char uniname2ctype_pool_str2023[sizeof("spacingmark")];
     char uniname2ctype_pool_str2024[sizeof("inpalmyrene")];
     char uniname2ctype_pool_str2026[sizeof("takr")];
     char uniname2ctype_pool_str2033[sizeof("xposixpunct")];
+    char uniname2ctype_pool_str2040[sizeof("inkhojki")];
     char uniname2ctype_pool_str2042[sizeof("taile")];
     char uniname2ctype_pool_str2043[sizeof("assigned")];
+    char uniname2ctype_pool_str2044[sizeof("hanunoo")];
+    char uniname2ctype_pool_str2047[sizeof("hira")];
+    char uniname2ctype_pool_str2048[sizeof("inarabicextendedc")];
     char uniname2ctype_pool_str2062[sizeof("newtailue")];
     char uniname2ctype_pool_str2070[sizeof("space")];
     char uniname2ctype_pool_str2073[sizeof("intelugu")];
@@ -41401,41 +42470,35 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str2278[sizeof("shaw")];
     char uniname2ctype_pool_str2279[sizeof("palmyrene")];
     char uniname2ctype_pool_str2283[sizeof("soyo")];
+    char uniname2ctype_pool_str2296[sizeof("incjkunifiedideographsextensionh")];
     char uniname2ctype_pool_str2305[sizeof("sgnw")];
     char uniname2ctype_pool_str2308[sizeof("toto")];
     char uniname2ctype_pool_str2312[sizeof("caucasianalbanian")];
     char uniname2ctype_pool_str2315[sizeof("inmathematicalalphanumericsymbols")];
     char uniname2ctype_pool_str2316[sizeof("incjkunifiedideographsextensiong")];
+    char uniname2ctype_pool_str2318[sizeof("hatran")];
     char uniname2ctype_pool_str2321[sizeof("taiviet")];
     char uniname2ctype_pool_str2323[sizeof("meroitichieroglyphs")];
     char uniname2ctype_pool_str2327[sizeof("ingeorgianextended")];
     char uniname2ctype_pool_str2331[sizeof("incjkunifiedideographsextensionf")];
     char uniname2ctype_pool_str2333[sizeof("oldpersian")];
-    char uniname2ctype_pool_str2341[sizeof("mahj")];
     char uniname2ctype_pool_str2343[sizeof("induployan")];
     char uniname2ctype_pool_str2344[sizeof("incyrillicextendedb")];
     char uniname2ctype_pool_str2345[sizeof("dash")];
-    char uniname2ctype_pool_str2350[sizeof("mahajani")];
-    char uniname2ctype_pool_str2351[sizeof("hang")];
+    char uniname2ctype_pool_str2353[sizeof("hatr")];
     char uniname2ctype_pool_str2361[sizeof("innyiakengpuachuehmong")];
     char uniname2ctype_pool_str2364[sizeof("incombiningdiacriticalmarks")];
-    char uniname2ctype_pool_str2370[sizeof("ingujarati")];
     char uniname2ctype_pool_str2373[sizeof("nl")];
     char uniname2ctype_pool_str2374[sizeof("incombiningdiacriticalmarksforsymbols")];
     char uniname2ctype_pool_str2375[sizeof("khudawadi")];
-    char uniname2ctype_pool_str2389[sizeof("ingunjalagondi")];
     char uniname2ctype_pool_str2397[sizeof("incjkradicalssupplement")];
     char uniname2ctype_pool_str2398[sizeof("inglagolitic")];
     char uniname2ctype_pool_str2405[sizeof("orkh")];
-    char uniname2ctype_pool_str2406[sizeof("hiragana")];
     char uniname2ctype_pool_str2414[sizeof("syrc")];
-    char uniname2ctype_pool_str2418[sizeof("inrejang")];
     char uniname2ctype_pool_str2427[sizeof("surrogate")];
-    char uniname2ctype_pool_str2428[sizeof("khoj")];
     char uniname2ctype_pool_str2433[sizeof("indevanagari")];
     char uniname2ctype_pool_str2434[sizeof("avestan")];
     char uniname2ctype_pool_str2437[sizeof("oldpermic")];
-    char uniname2ctype_pool_str2438[sizeof("hmng")];
     char uniname2ctype_pool_str2440[sizeof("ethi")];
     char uniname2ctype_pool_str2451[sizeof("ogam")];
     char uniname2ctype_pool_str2454[sizeof("rohg")];
@@ -41443,7 +42506,7 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str2464[sizeof("java")];
     char uniname2ctype_pool_str2470[sizeof("inphagspa")];
     char uniname2ctype_pool_str2475[sizeof("lepcha")];
-    char uniname2ctype_pool_str2476[sizeof("inenclosedcjklettersandmonths")];
+    char uniname2ctype_pool_str2476[sizeof("indevanagariextendeda")];
     char uniname2ctype_pool_str2478[sizeof("intifinagh")];
     char uniname2ctype_pool_str2479[sizeof("intagalog")];
     char uniname2ctype_pool_str2481[sizeof("incombiningdiacriticalmarkssupplement")];
@@ -41453,6 +42516,7 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str2513[sizeof("insymbolsandpictographsextendeda")];
     char uniname2ctype_pool_str2530[sizeof("syriac")];
     char uniname2ctype_pool_str2534[sizeof("inbengali")];
+    char uniname2ctype_pool_str2535[sizeof("nagm")];
     char uniname2ctype_pool_str2545[sizeof("extendedpictographic")];
     char uniname2ctype_pool_str2548[sizeof("buhd")];
     char uniname2ctype_pool_str2549[sizeof("javanese")];
@@ -41461,6 +42525,7 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str2567[sizeof("inlatin1supplement")];
     char uniname2ctype_pool_str2570[sizeof("ingothic")];
     char uniname2ctype_pool_str2572[sizeof("invariationselectors")];
+    char uniname2ctype_pool_str2574[sizeof("hex")];
     char uniname2ctype_pool_str2575[sizeof("inverticalforms")];
     char uniname2ctype_pool_str2576[sizeof("ebase")];
     char uniname2ctype_pool_str2582[sizeof("incurrencysymbols")];
@@ -41474,15 +42539,15 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str2652[sizeof("invedicextensions")];
     char uniname2ctype_pool_str2656[sizeof("inlimbu")];
     char uniname2ctype_pool_str2657[sizeof("olditalic")];
-    char uniname2ctype_pool_str2660[sizeof("rjng")];
+    char uniname2ctype_pool_str2665[sizeof("gujr")];
     char uniname2ctype_pool_str2666[sizeof("mathsymbol")];
     char uniname2ctype_pool_str2670[sizeof("incjkunifiedideographsextensionb")];
+    char uniname2ctype_pool_str2674[sizeof("gujarati")];
     char uniname2ctype_pool_str2688[sizeof("phagspa")];
     char uniname2ctype_pool_str2689[sizeof("invariationselectorssupplement")];
     char uniname2ctype_pool_str2694[sizeof("currencysymbol")];
     char uniname2ctype_pool_str2705[sizeof("inlinearbsyllabary")];
     char uniname2ctype_pool_str2726[sizeof("wancho")];
-    char uniname2ctype_pool_str2738[sizeof("hmnp")];
     char uniname2ctype_pool_str2750[sizeof("inpaucinhau")];
     char uniname2ctype_pool_str2761[sizeof("other")];
     char uniname2ctype_pool_str2762[sizeof("otheridcontinue")];
@@ -41492,7 +42557,6 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str2772[sizeof("warangciti")];
     char uniname2ctype_pool_str2775[sizeof("othernumber")];
     char uniname2ctype_pool_str2786[sizeof("digit")];
-    char uniname2ctype_pool_str2787[sizeof("hebr")];
     char uniname2ctype_pool_str2793[sizeof("nonspacingmark")];
     char uniname2ctype_pool_str2801[sizeof("titlecaseletter")];
     char uniname2ctype_pool_str2808[sizeof("inmeroiticcursive")];
@@ -41512,7 +42576,6 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str2871[sizeof("noncharactercodepoint")];
     char uniname2ctype_pool_str2879[sizeof("oldhungarian")];
     char uniname2ctype_pool_str2886[sizeof("insymbolsforlegacycomputing")];
-    char uniname2ctype_pool_str2901[sizeof("hangul")];
     char uniname2ctype_pool_str2902[sizeof("insmallformvariants")];
     char uniname2ctype_pool_str2904[sizeof("inhangulsyllables")];
     char uniname2ctype_pool_str2905[sizeof("emojipresentation")];
@@ -41524,15 +42587,12 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str2964[sizeof("inpsalterpahlavi")];
     char uniname2ctype_pool_str2966[sizeof("whitespace")];
     char uniname2ctype_pool_str2967[sizeof("finalpunctuation")];
-    char uniname2ctype_pool_str2969[sizeof("hung")];
     char uniname2ctype_pool_str2970[sizeof("orya")];
-    char uniname2ctype_pool_str2972[sizeof("hexdigit")];
     char uniname2ctype_pool_str2980[sizeof("phlp")];
     char uniname2ctype_pool_str2984[sizeof("inbamumsupplement")];
     char uniname2ctype_pool_str2986[sizeof("buhid")];
     char uniname2ctype_pool_str2987[sizeof("paragraphseparator")];
     char uniname2ctype_pool_str2988[sizeof("inalphabeticpresentationforms")];
-    char uniname2ctype_pool_str2993[sizeof("hluw")];
     char uniname2ctype_pool_str2997[sizeof("inlatinextendedg")];
     char uniname2ctype_pool_str3001[sizeof("elba")];
     char uniname2ctype_pool_str3002[sizeof("changeswhentitlecased")];
@@ -41549,30 +42609,39 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str3048[sizeof("tagbanwa")];
     char uniname2ctype_pool_str3052[sizeof("tamil")];
     char uniname2ctype_pool_str3053[sizeof("khitansmallscript")];
+    char uniname2ctype_pool_str3058[sizeof("mahj")];
+    char uniname2ctype_pool_str3067[sizeof("mahajani")];
+    char uniname2ctype_pool_str3068[sizeof("hang")];
     char uniname2ctype_pool_str3071[sizeof("tirh")];
     char uniname2ctype_pool_str3072[sizeof("sylotinagri")];
     char uniname2ctype_pool_str3082[sizeof("talu")];
+    char uniname2ctype_pool_str3084[sizeof("nagmundari")];
     char uniname2ctype_pool_str3086[sizeof("deva")];
+    char uniname2ctype_pool_str3087[sizeof("ingujarati")];
     char uniname2ctype_pool_str3091[sizeof("deprecated")];
     char uniname2ctype_pool_str3099[sizeof("inarabicpresentationformsb")];
     char uniname2ctype_pool_str3104[sizeof("devanagari")];
+    char uniname2ctype_pool_str3106[sizeof("ingunjalagondi")];
     char uniname2ctype_pool_str3107[sizeof("graphemeclusterbreak=t")];
     char uniname2ctype_pool_str3109[sizeof("graphemeclusterbreak=lvt")];
     char uniname2ctype_pool_str3110[sizeof("taitham")];
     char uniname2ctype_pool_str3111[sizeof("nbat")];
     char uniname2ctype_pool_str3118[sizeof("telu")];
+    char uniname2ctype_pool_str3123[sizeof("hiragana")];
     char uniname2ctype_pool_str3125[sizeof("nabataean")];
-    char uniname2ctype_pool_str3140[sizeof("inmahjongtiles")];
+    char uniname2ctype_pool_str3135[sizeof("inrejang")];
     char uniname2ctype_pool_str3142[sizeof("intangutsupplement")];
+    char uniname2ctype_pool_str3145[sizeof("khoj")];
+    char uniname2ctype_pool_str3155[sizeof("hmng")];
     char uniname2ctype_pool_str3157[sizeof("cyprominoan")];
     char uniname2ctype_pool_str3158[sizeof("inhebrew")];
     char uniname2ctype_pool_str3176[sizeof("inmathematicaloperators")];
     char uniname2ctype_pool_str3180[sizeof("inarabicsupplement")];
+    char uniname2ctype_pool_str3193[sizeof("inenclosedcjklettersandmonths")];
     char uniname2ctype_pool_str3209[sizeof("changeswhenlowercased")];
     char uniname2ctype_pool_str3212[sizeof("tangut")];
     char uniname2ctype_pool_str3215[sizeof("elbasan")];
     char uniname2ctype_pool_str3218[sizeof("osmanya")];
-    char uniname2ctype_pool_str3227[sizeof("inyijinghexagramsymbols")];
     char uniname2ctype_pool_str3237[sizeof("insuperscriptsandsubscripts")];
     char uniname2ctype_pool_str3239[sizeof("graphemeclusterbreak=extend")];
     char uniname2ctype_pool_str3240[sizeof("graphemeclusterbreak=prepend")];
@@ -41583,7 +42652,6 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str3275[sizeof("kayahli")];
     char uniname2ctype_pool_str3284[sizeof("inplayingcards")];
     char uniname2ctype_pool_str3287[sizeof("elym")];
-    char uniname2ctype_pool_str3290[sizeof("injavanese")];
     char uniname2ctype_pool_str3297[sizeof("graphemeclusterbreak=l")];
     char uniname2ctype_pool_str3303[sizeof("graphemeclusterbreak=control")];
     char uniname2ctype_pool_str3313[sizeof("ogrext")];
@@ -41599,6 +42667,7 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str3371[sizeof("cypriot")];
     char uniname2ctype_pool_str3372[sizeof("any")];
     char uniname2ctype_pool_str3373[sizeof("otheruppercase")];
+    char uniname2ctype_pool_str3377[sizeof("rjng")];
     char uniname2ctype_pool_str3391[sizeof("wspace")];
     char uniname2ctype_pool_str3396[sizeof("inindicsiyaqnumbers")];
     char uniname2ctype_pool_str3405[sizeof("inprivateusearea")];
@@ -41606,11 +42675,12 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str3428[sizeof("oupper")];
     char uniname2ctype_pool_str3433[sizeof("signwriting")];
     char uniname2ctype_pool_str3436[sizeof("nushu")];
-    char uniname2ctype_pool_str3452[sizeof("hanifirohingya")];
+    char uniname2ctype_pool_str3455[sizeof("hmnp")];
     char uniname2ctype_pool_str3458[sizeof("upper")];
     char uniname2ctype_pool_str3460[sizeof("insupplementalarrowsc")];
     char uniname2ctype_pool_str3483[sizeof("omath")];
     char uniname2ctype_pool_str3502[sizeof("modifiersymbol")];
+    char uniname2ctype_pool_str3504[sizeof("hebr")];
     char uniname2ctype_pool_str3505[sizeof("inhalfwidthandfullwidthforms")];
     char uniname2ctype_pool_str3511[sizeof("insupplementalmathematicaloperators")];
     char uniname2ctype_pool_str3532[sizeof("inpahawhhmong")];
@@ -41619,60 +42689,68 @@ struct uniname2ctype_pool_t
     char uniname2ctype_pool_str3580[sizeof("dupl")];
     char uniname2ctype_pool_str3590[sizeof("ogham")];
     char uniname2ctype_pool_str3613[sizeof("dashpunctuation")];
+    char uniname2ctype_pool_str3618[sizeof("hangul")];
     char uniname2ctype_pool_str3648[sizeof("inhanguljamoextendedb")];
     char uniname2ctype_pool_str3659[sizeof("bassavah")];
     char uniname2ctype_pool_str3664[sizeof("aghb")];
+    char uniname2ctype_pool_str3686[sizeof("hung")];
+    char uniname2ctype_pool_str3689[sizeof("hexdigit")];
     char uniname2ctype_pool_str3698[sizeof("incypriotsyllabary")];
     char uniname2ctype_pool_str3699[sizeof("indivesakuru")];
     char uniname2ctype_pool_str3701[sizeof("tibt")];
     char uniname2ctype_pool_str3705[sizeof("inlatinextendedb")];
+    char uniname2ctype_pool_str3710[sizeof("hluw")];
     char uniname2ctype_pool_str3713[sizeof("tibetan")];
     char uniname2ctype_pool_str3721[sizeof("inyisyllables")];
     char uniname2ctype_pool_str3744[sizeof("oldnortharabian")];
     char uniname2ctype_pool_str3754[sizeof("defaultignorablecodepoint")];
     char uniname2ctype_pool_str3766[sizeof("inhighprivateusesurrogates")];
-    char uniname2ctype_pool_str3770[sizeof("rejang")];
     char uniname2ctype_pool_str3799[sizeof("soyombo")];
     char uniname2ctype_pool_str3807[sizeof("otherdefaultignorablecodepoint")];
     char uniname2ctype_pool_str3842[sizeof("pahawhhmong")];
     char uniname2ctype_pool_str3845[sizeof("unifiedideograph")];
     char uniname2ctype_pool_str3850[sizeof("othermath")];
     char uniname2ctype_pool_str3854[sizeof("changeswhencasefolded")];
+    char uniname2ctype_pool_str3857[sizeof("inmahjongtiles")];
     char uniname2ctype_pool_str3868[sizeof("dep")];
     char uniname2ctype_pool_str3881[sizeof("divesakuru")];
     char uniname2ctype_pool_str3884[sizeof("graphemeclusterbreak=lf")];
     char uniname2ctype_pool_str3891[sizeof("uppercaseletter")];
     char uniname2ctype_pool_str3924[sizeof("insupplementalpunctuation")];
     char uniname2ctype_pool_str3942[sizeof("ethiopic")];
+    char uniname2ctype_pool_str3944[sizeof("inyijinghexagramsymbols")];
     char uniname2ctype_pool_str3949[sizeof("ecomp")];
     char uniname2ctype_pool_str3976[sizeof("inglagoliticsupplement")];
-    char uniname2ctype_pool_str3978[sizeof("hebrew")];
     char uniname2ctype_pool_str3998[sizeof("inbopomofoextended")];
-    char uniname2ctype_pool_str4066[sizeof("graphemeclusterbreak=zwj")];
+    char uniname2ctype_pool_str4007[sizeof("injavanese")];
     char uniname2ctype_pool_str4106[sizeof("otherpunctuation")];
     char uniname2ctype_pool_str4116[sizeof("tifinagh")];
     char uniname2ctype_pool_str4127[sizeof("tfng")];
+    char uniname2ctype_pool_str4169[sizeof("hanifirohingya")];
     char uniname2ctype_pool_str4231[sizeof("tavt")];
     char uniname2ctype_pool_str4308[sizeof("inboxdrawing")];
     char uniname2ctype_pool_str4309[sizeof("oldsoutharabian")];
-    char uniname2ctype_pool_str4321[sizeof("hyphen")];
     char uniname2ctype_pool_str4348[sizeof("inegyptianhieroglyphs")];
     char uniname2ctype_pool_str4361[sizeof("inegyptianhieroglyphformatcontrols")];
     char uniname2ctype_pool_str4459[sizeof("tagb")];
+    char uniname2ctype_pool_str4487[sizeof("rejang")];
     char uniname2ctype_pool_str4604[sizeof("tglg")];
     char uniname2ctype_pool_str4626[sizeof("tagalog")];
     char uniname2ctype_pool_str4627[sizeof("othergraphemeextend")];
     char uniname2ctype_pool_str4674[sizeof("insupplementaryprivateuseareaa")];
     char uniname2ctype_pool_str4683[sizeof("inhighsurrogates")];
+    char uniname2ctype_pool_str4695[sizeof("hebrew")];
     char uniname2ctype_pool_str4734[sizeof("duployan")];
     char uniname2ctype_pool_str4755[sizeof("graphemeclusterbreak=v")];
     char uniname2ctype_pool_str4756[sizeof("graphemeclusterbreak=lv")];
     char uniname2ctype_pool_str4772[sizeof("insupplementalarrowsb")];
+    char uniname2ctype_pool_str4783[sizeof("graphemeclusterbreak=zwj")];
     char uniname2ctype_pool_str4810[sizeof("telugu")];
     char uniname2ctype_pool_str4898[sizeof("zyyy")];
     char uniname2ctype_pool_str4982[sizeof("olduyghur")];
     char uniname2ctype_pool_str4986[sizeof("inhangulcompatibilityjamo")];
     char uniname2ctype_pool_str5018[sizeof("openpunctuation")];
+    char uniname2ctype_pool_str5038[sizeof("hyphen")];
     char uniname2ctype_pool_str5134[sizeof("insupplementalsymbolsandpictographs")];
     char uniname2ctype_pool_str5141[sizeof("egyp")];
     char uniname2ctype_pool_str5300[sizeof("nyiakengpuachuehmong")];
@@ -41849,6 +42927,7 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "innewa",
     "sk",
     "control",
+    "inkawi",
     "inancientsymbols",
     "palm",
     "inlycian",
@@ -41863,6 +42942,7 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "inwarangciti",
     "sora",
     "inopticalcharacterrecognition",
+    "kawi",
     "inoldsogdian",
     "inmalayalam",
     "bamum",
@@ -41995,11 +43075,13 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "inogham",
     "cher",
     "chakma",
+    "inkaktoviknumerals",
     "emoji",
     "insiddham",
     "cherokee",
     "khar",
     "inmongolian",
+    "innagmundari",
     "incherokeesupplement",
     "manichaean",
     "inolchiki",
@@ -42043,48 +43125,46 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
 #ifdef USE_UNICODE_AGE_PROPERTIES
     "age=6.0",
     "age=6.2",
+    "age=15.0",
     "age=7.0",
     "age=6.3",
 #endif /* USE_UNICODE_AGE_PROPERTIES */
     "cwt",
 #ifdef USE_UNICODE_AGE_PROPERTIES
-    "age=5.1",
+    "age=14.0",
 #endif /* USE_UNICODE_AGE_PROPERTIES */
     "unassigned",
 #ifdef USE_UNICODE_AGE_PROPERTIES
+    "age=5.1",
     "age=5.0",
     "age=5.2",
-    "age=14.0",
 #endif /* USE_UNICODE_AGE_PROPERTIES */
     "diacritic",
-    "ahom",
 #ifdef USE_UNICODE_AGE_PROPERTIES
     "age=4.1",
+#endif /* USE_UNICODE_AGE_PROPERTIES */
+    "ahom",
+#ifdef USE_UNICODE_AGE_PROPERTIES
     "age=4.0",
 #endif /* USE_UNICODE_AGE_PROPERTIES */
     "incjkunifiedideographsextensione",
-    "hani",
     "khmr",
-    "han",
     "insinhala",
     "inmiscellaneoustechnical",
     "saur",
-    "hano",
     "guru",
     "sundanese",
     "punct",
     "paucinhau",
     "gurmukhi",
-    "inkhojki",
-    "hanunoo",
     "chorasmian",
-    "hira",
     "logicalorderexception",
     "khmer",
     "limbu",
     "chrs",
     "oriya",
     "inscriptionalpahlavi",
+    "incyrillicextendedd",
     "incjkunifiedideographsextensionc",
 #endif /* USE_UNICODE_PROPERTIES */
     "cntrl",
@@ -42156,7 +43236,6 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "indogra",
     "arab",
     "medefaidrin",
-    "hatran",
     "inshorthandformatcontrols",
     "phli",
     "inimperialaramaic",
@@ -42165,7 +43244,6 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "inanatolianhieroglyphs",
     "punctuation",
     "graphemeextend",
-    "hatr",
     "cwl",
     "vith",
     "ingeometricshapes",
@@ -42223,7 +43301,6 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "oidc",
     "bopo",
     "cuneiform",
-    "hex",
     "caseignorable",
     "inoldpersian",
     "cwu",
@@ -42242,10 +43319,8 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "oids",
     "inarabicextendeda",
     "modifierletter",
-    "gujr",
     "incjksymbolsandpunctuation",
     "olower",
-    "gujarati",
     "bopomofo",
     "inlisu",
     "inoldpermic",
@@ -42259,12 +43334,15 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "inbalinese",
     "sorasompeng",
     "closepunctuation",
+    "hani",
     "inmayannumerals",
+    "han",
     "inmiscellaneousmathematicalsymbolsb",
     "inlepcha",
     "patsyn",
     "inlisusupplement",
     "insyriacsupplement",
+    "hano",
     "newa",
     "spacingmark",
     "inpalmyrene",
@@ -42274,8 +43352,12 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
 #ifndef USE_UNICODE_PROPERTIES
     "lower",
 #else /* USE_UNICODE_PROPERTIES */
+    "inkhojki",
     "taile",
     "assigned",
+    "hanunoo",
+    "hira",
+    "inarabicextendedc",
     "newtailue",
     "space",
     "intelugu",
@@ -42328,41 +43410,35 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "shaw",
     "palmyrene",
     "soyo",
+    "incjkunifiedideographsextensionh",
     "sgnw",
     "toto",
     "caucasianalbanian",
     "inmathematicalalphanumericsymbols",
     "incjkunifiedideographsextensiong",
+    "hatran",
     "taiviet",
     "meroitichieroglyphs",
     "ingeorgianextended",
     "incjkunifiedideographsextensionf",
     "oldpersian",
-    "mahj",
     "induployan",
     "incyrillicextendedb",
     "dash",
-    "mahajani",
-    "hang",
+    "hatr",
     "innyiakengpuachuehmong",
     "incombiningdiacriticalmarks",
-    "ingujarati",
     "nl",
     "incombiningdiacriticalmarksforsymbols",
     "khudawadi",
-    "ingunjalagondi",
     "incjkradicalssupplement",
     "inglagolitic",
     "orkh",
-    "hiragana",
     "syrc",
-    "inrejang",
     "surrogate",
-    "khoj",
     "indevanagari",
     "avestan",
     "oldpermic",
-    "hmng",
     "ethi",
     "ogam",
     "rohg",
@@ -42370,7 +43446,7 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "java",
     "inphagspa",
     "lepcha",
-    "inenclosedcjklettersandmonths",
+    "indevanagariextendeda",
     "intifinagh",
     "intagalog",
     "incombiningdiacriticalmarkssupplement",
@@ -42380,6 +43456,7 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "insymbolsandpictographsextendeda",
     "syriac",
     "inbengali",
+    "nagm",
     "extendedpictographic",
     "buhd",
     "javanese",
@@ -42388,6 +43465,7 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "inlatin1supplement",
     "ingothic",
     "invariationselectors",
+    "hex",
     "inverticalforms",
     "ebase",
     "incurrencysymbols",
@@ -42401,15 +43479,15 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "invedicextensions",
     "inlimbu",
     "olditalic",
-    "rjng",
+    "gujr",
     "mathsymbol",
     "incjkunifiedideographsextensionb",
+    "gujarati",
     "phagspa",
     "invariationselectorssupplement",
     "currencysymbol",
     "inlinearbsyllabary",
     "wancho",
-    "hmnp",
     "inpaucinhau",
     "other",
     "otheridcontinue",
@@ -42423,7 +43501,6 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
 #ifndef USE_UNICODE_PROPERTIES
     "blank"
 #else /* USE_UNICODE_PROPERTIES */
-    "hebr",
     "nonspacingmark",
     "titlecaseletter",
     "inmeroiticcursive",
@@ -42443,7 +43520,6 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "noncharactercodepoint",
     "oldhungarian",
     "insymbolsforlegacycomputing",
-    "hangul",
     "insmallformvariants",
     "inhangulsyllables",
     "emojipresentation",
@@ -42455,15 +43531,12 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "inpsalterpahlavi",
     "whitespace",
     "finalpunctuation",
-    "hung",
     "orya",
-    "hexdigit",
     "phlp",
     "inbamumsupplement",
     "buhid",
     "paragraphseparator",
     "inalphabeticpresentationforms",
-    "hluw",
     "inlatinextendedg",
     "elba",
     "changeswhentitlecased",
@@ -42480,30 +43553,39 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "tagbanwa",
     "tamil",
     "khitansmallscript",
+    "mahj",
+    "mahajani",
+    "hang",
     "tirh",
     "sylotinagri",
     "talu",
+    "nagmundari",
     "deva",
+    "ingujarati",
     "deprecated",
     "inarabicpresentationformsb",
     "devanagari",
+    "ingunjalagondi",
     "graphemeclusterbreak=t",
     "graphemeclusterbreak=lvt",
     "taitham",
     "nbat",
     "telu",
+    "hiragana",
     "nabataean",
-    "inmahjongtiles",
+    "inrejang",
     "intangutsupplement",
+    "khoj",
+    "hmng",
     "cyprominoan",
     "inhebrew",
     "inmathematicaloperators",
     "inarabicsupplement",
+    "inenclosedcjklettersandmonths",
     "changeswhenlowercased",
     "tangut",
     "elbasan",
     "osmanya",
-    "inyijinghexagramsymbols",
     "insuperscriptsandsubscripts",
     "graphemeclusterbreak=extend",
     "graphemeclusterbreak=prepend",
@@ -42514,7 +43596,6 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "kayahli",
     "inplayingcards",
     "elym",
-    "injavanese",
     "graphemeclusterbreak=l",
     "graphemeclusterbreak=control",
     "ogrext",
@@ -42530,6 +43611,7 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "cypriot",
     "any",
     "otheruppercase",
+    "rjng",
     "wspace",
     "inindicsiyaqnumbers",
     "inprivateusearea",
@@ -42537,11 +43619,12 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "oupper",
     "signwriting",
     "nushu",
-    "hanifirohingya",
+    "hmnp",
     "upper",
     "insupplementalarrowsc",
     "omath",
     "modifiersymbol",
+    "hebr",
     "inhalfwidthandfullwidthforms",
     "insupplementalmathematicaloperators",
     "inpahawhhmong",
@@ -42550,60 +43633,68 @@ static const struct uniname2ctype_pool_t uniname2ctype_pool_contents =
     "dupl",
     "ogham",
     "dashpunctuation",
+    "hangul",
     "inhanguljamoextendedb",
     "bassavah",
     "aghb",
+    "hung",
+    "hexdigit",
     "incypriotsyllabary",
     "indivesakuru",
     "tibt",
     "inlatinextendedb",
+    "hluw",
     "tibetan",
     "inyisyllables",
     "oldnortharabian",
     "defaultignorablecodepoint",
     "inhighprivateusesurrogates",
-    "rejang",
     "soyombo",
     "otherdefaultignorablecodepoint",
     "pahawhhmong",
     "unifiedideograph",
     "othermath",
     "changeswhencasefolded",
+    "inmahjongtiles",
     "dep",
     "divesakuru",
     "graphemeclusterbreak=lf",
     "uppercaseletter",
     "insupplementalpunctuation",
     "ethiopic",
+    "inyijinghexagramsymbols",
     "ecomp",
     "inglagoliticsupplement",
-    "hebrew",
     "inbopomofoextended",
-    "graphemeclusterbreak=zwj",
+    "injavanese",
     "otherpunctuation",
     "tifinagh",
     "tfng",
+    "hanifirohingya",
     "tavt",
     "inboxdrawing",
     "oldsoutharabian",
-    "hyphen",
     "inegyptianhieroglyphs",
     "inegyptianhieroglyphformatcontrols",
     "tagb",
+    "rejang",
     "tglg",
     "tagalog",
     "othergraphemeextend",
     "insupplementaryprivateuseareaa",
     "inhighsurrogates",
+    "hebrew",
     "duployan",
     "graphemeclusterbreak=v",
     "graphemeclusterbreak=lv",
     "insupplementalarrowsb",
+    "graphemeclusterbreak=zwj",
     "telugu",
     "zyyy",
     "olduyghur",
     "inhangulcompatibilityjamo",
     "openpunctuation",
+    "hyphen",
     "insupplementalsymbolsandpictographs",
     "egyp",
     "nyiakengpuachuehmong",
@@ -42639,13 +43730,13 @@ uniname2ctype_p (register const char *str, register size_t len)
       {uniname2ctype_offset(str48), 95},
       {uniname2ctype_offset(str49), 95},
       {-1}, {-1},
-      {uniname2ctype_offset(str52), 343},
+      {uniname2ctype_offset(str52), 346},
       {-1}, {-1},
       {uniname2ctype_offset(str55), 21},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str64), 44},
       {-1},
-      {uniname2ctype_offset(str66), 330},
+      {uniname2ctype_offset(str66), 333},
       {uniname2ctype_offset(str67), 52},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str71), 181},
@@ -42663,9 +43754,9 @@ uniname2ctype_p (register const char *str, register size_t len)
       {uniname2ctype_offset(str94), 33},
       {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str100), 149},
-      {uniname2ctype_offset(str101), 510},
+      {uniname2ctype_offset(str101), 513},
       {uniname2ctype_offset(str102), 108},
-      {uniname2ctype_offset(str103), 261},
+      {uniname2ctype_offset(str103), 263},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str107), 31},
       {uniname2ctype_offset(str108), 77},
@@ -42684,27 +43775,27 @@ uniname2ctype_p (register const char *str, register size_t len)
       {uniname2ctype_offset(str130), 42},
       {uniname2ctype_offset(str131), 172},
       {-1}, {-1},
-      {uniname2ctype_offset(str134), 494},
+      {uniname2ctype_offset(str134), 497},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str139), 170},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str145), 513},
-      {uniname2ctype_offset(str146), 569},
+      {uniname2ctype_offset(str145), 516},
+      {uniname2ctype_offset(str146), 575},
       {-1},
-      {uniname2ctype_offset(str148), 574},
-      {uniname2ctype_offset(str149), 531},
+      {uniname2ctype_offset(str148), 580},
+      {uniname2ctype_offset(str149), 535},
       {-1},
       {uniname2ctype_offset(str151), 18},
       {uniname2ctype_offset(str152), 169},
       {uniname2ctype_offset(str153), 160},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str158), 276},
+      {uniname2ctype_offset(str158), 278},
       {-1}, {-1},
-      {uniname2ctype_offset(str161), 324},
+      {uniname2ctype_offset(str161), 327},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str177), 349},
-      {uniname2ctype_offset(str178), 558},
+      {uniname2ctype_offset(str177), 352},
+      {uniname2ctype_offset(str178), 563},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str183), 75},
       {-1}, {-1},
@@ -42713,19 +43804,19 @@ uniname2ctype_p (register const char *str, register size_t len)
       {uniname2ctype_offset(str190), 208},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str203), 357},
-      {uniname2ctype_offset(str204), 485},
+      {uniname2ctype_offset(str203), 360},
+      {uniname2ctype_offset(str204), 488},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str210), 575},
+      {uniname2ctype_offset(str210), 581},
       {-1},
-      {uniname2ctype_offset(str212), 362},
+      {uniname2ctype_offset(str212), 365},
       {uniname2ctype_offset(str213), 115},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str218), 545},
+      {uniname2ctype_offset(str218), 549},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str226), 171},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str230), 526},
+      {uniname2ctype_offset(str230), 530},
       {uniname2ctype_offset(str231), 31},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str236), 25},
@@ -42737,64 +43828,64 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1},
       {uniname2ctype_offset(str253), 102},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str260), 562},
+      {uniname2ctype_offset(str260), 568},
       {-1}, {-1},
       {uniname2ctype_offset(str263), 161},
       {-1},
       {uniname2ctype_offset(str265), 19},
       {-1},
       {uniname2ctype_offset(str267), 79},
-      {uniname2ctype_offset(str268), 354},
+      {uniname2ctype_offset(str268), 357},
       {-1},
-      {uniname2ctype_offset(str270), 268},
+      {uniname2ctype_offset(str270), 270},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str274), 561},
-      {uniname2ctype_offset(str275), 514},
+      {uniname2ctype_offset(str274), 567},
+      {uniname2ctype_offset(str275), 517},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str281), 318},
+      {uniname2ctype_offset(str281), 321},
       {uniname2ctype_offset(str282), 40},
       {uniname2ctype_offset(str283), 79},
       {-1},
-      {uniname2ctype_offset(str285), 533},
+      {uniname2ctype_offset(str285), 537},
       {-1},
       {uniname2ctype_offset(str287), 144},
       {uniname2ctype_offset(str288), 144},
-      {uniname2ctype_offset(str289), 555},
+      {uniname2ctype_offset(str289), 560},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str293), 218},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str297), 212},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str301), 392},
+      {uniname2ctype_offset(str301), 395},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str311), 322},
+      {uniname2ctype_offset(str311), 325},
       {-1},
-      {uniname2ctype_offset(str313), 453},
+      {uniname2ctype_offset(str313), 456},
       {-1},
-      {uniname2ctype_offset(str315), 241},
+      {uniname2ctype_offset(str315), 243},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str320), 269},
+      {uniname2ctype_offset(str320), 271},
       {-1},
       {uniname2ctype_offset(str322), 129},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str328), 331},
+      {uniname2ctype_offset(str328), 334},
       {-1}, {-1},
       {uniname2ctype_offset(str331), 76},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str335), 556},
+      {uniname2ctype_offset(str335), 561},
       {-1}, {-1},
-      {uniname2ctype_offset(str338), 329},
+      {uniname2ctype_offset(str338), 332},
       {-1},
       {uniname2ctype_offset(str340), 76},
       {-1},
-      {uniname2ctype_offset(str342), 346},
+      {uniname2ctype_offset(str342), 349},
       {-1}, {-1},
       {uniname2ctype_offset(str345), 53},
-      {uniname2ctype_offset(str346), 268},
+      {uniname2ctype_offset(str346), 270},
       {-1},
-      {uniname2ctype_offset(str348), 423},
+      {uniname2ctype_offset(str348), 426},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str352), 529},
+      {uniname2ctype_offset(str352), 533},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str362), 163},
       {-1}, {-1}, {-1},
@@ -42802,14 +43893,14 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str373), 160},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str381), 550},
+      {uniname2ctype_offset(str381), 554},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str386), 368},
+      {uniname2ctype_offset(str386), 371},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str399), 327},
+      {uniname2ctype_offset(str399), 330},
       {-1},
-      {uniname2ctype_offset(str401), 544},
+      {uniname2ctype_offset(str401), 548},
       {-1}, {-1},
       {uniname2ctype_offset(str404), 81},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
@@ -42832,176 +43923,179 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1},
       {uniname2ctype_offset(str470), 22},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str475), 521},
+      {uniname2ctype_offset(str475), 524},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str480), 454},
+      {uniname2ctype_offset(str480), 457},
       {uniname2ctype_offset(str481), 188},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str486), 473},
+      {uniname2ctype_offset(str486), 476},
       {-1},
-      {uniname2ctype_offset(str488), 582},
+      {uniname2ctype_offset(str488), 588},
       {-1}, {-1},
-      {uniname2ctype_offset(str491), 467},
+      {uniname2ctype_offset(str491), 470},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str500), 127},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str504), 187},
-      {uniname2ctype_offset(str505), 247},
+      {uniname2ctype_offset(str505), 249},
       {uniname2ctype_offset(str506), 24},
       {-1}, {-1},
       {uniname2ctype_offset(str509), 24},
       {-1},
-      {uniname2ctype_offset(str511), 460},
+      {uniname2ctype_offset(str511), 463},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str520), 420},
+      {uniname2ctype_offset(str520), 423},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str533), 230},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str538), 91},
       {-1}, {-1},
-      {uniname2ctype_offset(str541), 549},
+      {uniname2ctype_offset(str541), 553},
       {-1},
       {uniname2ctype_offset(str543), 91},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str556), 542},
+      {uniname2ctype_offset(str556), 546},
       {-1},
-      {uniname2ctype_offset(str558), 347},
+      {uniname2ctype_offset(str558), 350},
       {uniname2ctype_offset(str559), 70},
-      {uniname2ctype_offset(str560), 512},
+      {uniname2ctype_offset(str560), 515},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str565), 615},
+      {uniname2ctype_offset(str565), 624},
       {uniname2ctype_offset(str566), 37},
       {-1},
       {uniname2ctype_offset(str568), 113},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str572), 499},
+      {uniname2ctype_offset(str572), 502},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str577), 602},
+      {uniname2ctype_offset(str577), 611},
       {-1},
       {uniname2ctype_offset(str579), 106},
       {-1}, {-1},
-      {uniname2ctype_offset(str582), 403},
-      {uniname2ctype_offset(str583), 477},
+      {uniname2ctype_offset(str582), 406},
+      {uniname2ctype_offset(str583), 480},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str590), 74},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str594), 168},
       {-1},
-      {uniname2ctype_offset(str596), 613},
+      {uniname2ctype_offset(str596), 622},
       {uniname2ctype_offset(str597), 146},
       {-1}, {-1},
-      {uniname2ctype_offset(str600), 487},
+      {uniname2ctype_offset(str600), 490},
       {-1},
       {uniname2ctype_offset(str602), 70},
       {-1},
-      {uniname2ctype_offset(str604), 573},
-      {uniname2ctype_offset(str605), 620},
+      {uniname2ctype_offset(str604), 579},
+      {uniname2ctype_offset(str605), 629},
       {-1}, {-1},
-      {uniname2ctype_offset(str608), 628},
+      {uniname2ctype_offset(str608), 637},
       {uniname2ctype_offset(str609), 229},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str614), 603},
+      {uniname2ctype_offset(str614), 612},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str624), 195},
-      {uniname2ctype_offset(str625), 444},
+      {uniname2ctype_offset(str625), 447},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str630), 29},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str636), 539},
+      {uniname2ctype_offset(str636), 543},
       {-1}, {-1},
       {uniname2ctype_offset(str639), 49},
       {-1}, {-1},
       {uniname2ctype_offset(str642), 19},
-      {-1}, {-1},
-      {uniname2ctype_offset(str645), 482},
+      {uniname2ctype_offset(str643), 564},
+      {-1},
+      {uniname2ctype_offset(str645), 485},
       {-1},
       {uniname2ctype_offset(str647), 192},
       {-1}, {-1},
-      {uniname2ctype_offset(str650), 484},
+      {uniname2ctype_offset(str650), 487},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str657), 51},
       {-1}, {-1},
-      {uniname2ctype_offset(str660), 266},
+      {uniname2ctype_offset(str660), 268},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1},
-      {uniname2ctype_offset(str672), 332},
+      {uniname2ctype_offset(str672), 335},
       {-1}, {-1},
       {uniname2ctype_offset(str675), 68},
       {-1}, {-1},
       {uniname2ctype_offset(str678), 171},
-      {uniname2ctype_offset(str679), 599},
+      {uniname2ctype_offset(str679), 607},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str683), 265},
+      {uniname2ctype_offset(str683), 267},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str692), 69},
       {-1}, {-1},
-      {uniname2ctype_offset(str695), 547},
+      {uniname2ctype_offset(str695), 551},
       {uniname2ctype_offset(str696), 175},
-      {uniname2ctype_offset(str697), 396},
-      {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str703), 523},
+      {uniname2ctype_offset(str697), 399},
+      {-1}, {-1},
+      {uniname2ctype_offset(str700), 236},
+      {-1}, {-1},
+      {uniname2ctype_offset(str703), 527},
       {-1},
-      {uniname2ctype_offset(str705), 344},
+      {uniname2ctype_offset(str705), 347},
       {-1},
       {uniname2ctype_offset(str707), 158},
-      {uniname2ctype_offset(str708), 581},
+      {uniname2ctype_offset(str708), 587},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str713), 373},
+      {uniname2ctype_offset(str713), 376},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str720), 72},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str737), 7},
-      {uniname2ctype_offset(str738), 370},
+      {uniname2ctype_offset(str738), 373},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str742), 6},
       {-1}, {-1},
-      {uniname2ctype_offset(str745), 267},
+      {uniname2ctype_offset(str745), 269},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str753), 238},
+      {uniname2ctype_offset(str753), 240},
       {-1},
-      {uniname2ctype_offset(str755), 511},
+      {uniname2ctype_offset(str755), 514},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str760), 428},
+      {uniname2ctype_offset(str760), 431},
       {uniname2ctype_offset(str761), 167},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str766), 156},
-      {uniname2ctype_offset(str767), 600},
+      {uniname2ctype_offset(str767), 608},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str771), 167},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str776), 266},
+      {uniname2ctype_offset(str776), 268},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str783), 156},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str787), 254},
+      {uniname2ctype_offset(str787), 256},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str791), 193},
       {-1}, {-1},
-      {uniname2ctype_offset(str794), 583},
+      {uniname2ctype_offset(str794), 589},
       {-1}, {-1},
       {uniname2ctype_offset(str797), 50},
       {-1},
-      {uniname2ctype_offset(str799), 608},
+      {uniname2ctype_offset(str799), 617},
       {-1}, {-1},
       {uniname2ctype_offset(str802), 13},
-      {uniname2ctype_offset(str803), 587},
+      {uniname2ctype_offset(str803), 593},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str809), 443},
+      {uniname2ctype_offset(str809), 446},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str814), 490},
+      {uniname2ctype_offset(str814), 493},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str818), 395},
+      {uniname2ctype_offset(str818), 398},
       {-1}, {-1},
-      {uniname2ctype_offset(str821), 479},
-      {uniname2ctype_offset(str822), 589},
+      {uniname2ctype_offset(str821), 482},
+      {uniname2ctype_offset(str822), 595},
       {uniname2ctype_offset(str823), 47},
       {uniname2ctype_offset(str824), 112},
-      {uniname2ctype_offset(str825), 441},
+      {uniname2ctype_offset(str825), 444},
       {-1}, {-1},
-      {uniname2ctype_offset(str828), 590},
+      {uniname2ctype_offset(str828), 596},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str838), 157},
       {-1}, {-1}, {-1},
@@ -43014,32 +44108,32 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str855), 67},
       {-1},
-      {uniname2ctype_offset(str857), 316},
+      {uniname2ctype_offset(str857), 319},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str875), 366},
+      {uniname2ctype_offset(str875), 369},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1},
-      {uniname2ctype_offset(str886), 401},
+      {uniname2ctype_offset(str886), 404},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str895), 409},
+      {uniname2ctype_offset(str895), 412},
       {-1}, {-1},
-      {uniname2ctype_offset(str898), 497},
+      {uniname2ctype_offset(str898), 500},
       {-1},
-      {uniname2ctype_offset(str900), 612},
+      {uniname2ctype_offset(str900), 621},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str906), 518},
-      {uniname2ctype_offset(str907), 446},
+      {uniname2ctype_offset(str906), 521},
+      {uniname2ctype_offset(str907), 449},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str920), 416},
+      {uniname2ctype_offset(str920), 419},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str924), 68},
-      {uniname2ctype_offset(str925), 592},
-      {uniname2ctype_offset(str926), 341},
+      {uniname2ctype_offset(str925), 599},
+      {uniname2ctype_offset(str926), 344},
       {-1},
-      {uniname2ctype_offset(str928), 536},
-      {uniname2ctype_offset(str929), 458},
+      {uniname2ctype_offset(str928), 540},
+      {uniname2ctype_offset(str929), 461},
       {uniname2ctype_offset(str930), 41},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
@@ -43048,13 +44142,13 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str961), 2},
       {-1},
-      {uniname2ctype_offset(str963), 255},
+      {uniname2ctype_offset(str963), 257},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1},
-      {uniname2ctype_offset(str974), 507},
+      {uniname2ctype_offset(str974), 510},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1},
-      {uniname2ctype_offset(str986), 367},
+      {uniname2ctype_offset(str986), 370},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str994), 85},
       {uniname2ctype_offset(str995), 104},
@@ -43062,21 +44156,21 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1010), 26},
       {-1}, {-1},
-      {uniname2ctype_offset(str1013), 492},
+      {uniname2ctype_offset(str1013), 495},
       {-1},
-      {uniname2ctype_offset(str1015), 481},
+      {uniname2ctype_offset(str1015), 484},
       {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1021), 67},
       {-1}, {-1},
       {uniname2ctype_offset(str1024), 53},
-      {uniname2ctype_offset(str1025), 456},
+      {uniname2ctype_offset(str1025), 459},
       {-1}, {-1},
       {uniname2ctype_offset(str1028), 136},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1032), 377},
+      {uniname2ctype_offset(str1032), 380},
       {-1}, {-1},
-      {uniname2ctype_offset(str1035), 319},
-      {uniname2ctype_offset(str1036), 563},
+      {uniname2ctype_offset(str1035), 322},
+      {uniname2ctype_offset(str1036), 569},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1049), 173},
@@ -43086,26 +44180,26 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1072), 197},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1081), 411},
+      {uniname2ctype_offset(str1081), 414},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1085), 257},
+      {uniname2ctype_offset(str1085), 259},
       {-1},
-      {uniname2ctype_offset(str1087), 593},
+      {uniname2ctype_offset(str1087), 600},
       {-1},
       {uniname2ctype_offset(str1089), 115},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1095), 248},
+      {uniname2ctype_offset(str1095), 250},
       {uniname2ctype_offset(str1096), 71},
-      {uniname2ctype_offset(str1097), 537},
+      {uniname2ctype_offset(str1097), 541},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1102), 520},
+      {uniname2ctype_offset(str1102), 523},
       {-1},
       {uniname2ctype_offset(str1104), 228},
       {uniname2ctype_offset(str1105), 217},
       {-1},
-      {uniname2ctype_offset(str1107), 538},
+      {uniname2ctype_offset(str1107), 542},
       {-1},
-      {uniname2ctype_offset(str1109), 237},
+      {uniname2ctype_offset(str1109), 239},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1114), 69},
       {uniname2ctype_offset(str1115), 11},
@@ -43114,7 +44208,7 @@ uniname2ctype_p (register const char *str, register size_t len)
       {uniname2ctype_offset(str1120), 60},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1134), 422},
+      {uniname2ctype_offset(str1134), 425},
       {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1140), 93},
       {-1},
@@ -43122,153 +44216,155 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1},
       {uniname2ctype_offset(str1145), 137},
       {uniname2ctype_offset(str1146), 131},
-      {uniname2ctype_offset(str1147), 264},
+      {uniname2ctype_offset(str1147), 266},
       {-1},
       {uniname2ctype_offset(str1149), 158},
       {uniname2ctype_offset(str1150), 98},
-      {uniname2ctype_offset(str1151), 495},
+      {uniname2ctype_offset(str1151), 498},
       {uniname2ctype_offset(str1152), 217},
       {uniname2ctype_offset(str1153), 138},
       {-1}, {-1},
-      {uniname2ctype_offset(str1156), 525},
+      {uniname2ctype_offset(str1156), 529},
       {uniname2ctype_offset(str1157), 203},
       {uniname2ctype_offset(str1158), 166},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1164), 238},
+      {uniname2ctype_offset(str1164), 240},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1168), 104},
       {-1},
-      {uniname2ctype_offset(str1170), 386},
-      {uniname2ctype_offset(str1171), 532},
+      {uniname2ctype_offset(str1170), 389},
+      {uniname2ctype_offset(str1171), 536},
       {-1}, {-1},
-      {uniname2ctype_offset(str1174), 323},
+      {uniname2ctype_offset(str1174), 326},
       {uniname2ctype_offset(str1175), 26},
       {uniname2ctype_offset(str1176), 208},
       {uniname2ctype_offset(str1177), 74},
-      {uniname2ctype_offset(str1178), 350},
+      {uniname2ctype_offset(str1178), 353},
       {-1},
       {uniname2ctype_offset(str1180), 183},
       {uniname2ctype_offset(str1181), 151},
-      {uniname2ctype_offset(str1182), 356},
+      {uniname2ctype_offset(str1182), 359},
       {uniname2ctype_offset(str1183), 101},
       {-1},
       {uniname2ctype_offset(str1185), 170},
-      {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1190), 270},
-      {uniname2ctype_offset(str1191), 541},
+      {uniname2ctype_offset(str1186), 597},
+      {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str1190), 272},
+      {uniname2ctype_offset(str1191), 545},
       {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1197), 101},
       {uniname2ctype_offset(str1198), 135},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1203), 363},
-      {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1207), 459},
+      {uniname2ctype_offset(str1203), 366},
+      {uniname2ctype_offset(str1204), 609},
+      {-1}, {-1},
+      {uniname2ctype_offset(str1207), 462},
       {-1},
       {uniname2ctype_offset(str1209), 186},
       {-1}, {-1},
-      {uniname2ctype_offset(str1212), 376},
+      {uniname2ctype_offset(str1212), 379},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1},
-      {uniname2ctype_offset(str1223), 578},
+      {uniname2ctype_offset(str1223), 584},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1227), 241},
+      {uniname2ctype_offset(str1227), 243},
       {-1},
       {uniname2ctype_offset(str1229), 235},
-      {uniname2ctype_offset(str1230), 265},
+      {uniname2ctype_offset(str1230), 267},
       {uniname2ctype_offset(str1231), 206},
-      {uniname2ctype_offset(str1232), 352},
+      {uniname2ctype_offset(str1232), 355},
       {uniname2ctype_offset(str1233), 73},
 #ifndef USE_UNICODE_AGE_PROPERTIES
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
 #else /* USE_UNICODE_AGE_PROPERTIES */
-      {uniname2ctype_offset(str1234), 296},
-      {uniname2ctype_offset(str1235), 298},
-      {uniname2ctype_offset(str1236), 295},
-      {uniname2ctype_offset(str1237), 297},
+      {uniname2ctype_offset(str1234), 298},
+      {uniname2ctype_offset(str1235), 300},
+      {uniname2ctype_offset(str1236), 297},
+      {uniname2ctype_offset(str1237), 299},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1241), 299},
-      {uniname2ctype_offset(str1242), 277},
+      {uniname2ctype_offset(str1241), 301},
+      {uniname2ctype_offset(str1242), 279},
 #endif /* USE_UNICODE_AGE_PROPERTIES */
       {uniname2ctype_offset(str1243), 25},
-      {uniname2ctype_offset(str1244), 338},
+      {uniname2ctype_offset(str1244), 341},
 #ifndef USE_UNICODE_AGE_PROPERTIES
       {-1},
 #else /* USE_UNICODE_AGE_PROPERTIES */
-      {uniname2ctype_offset(str1245), 279},
+      {uniname2ctype_offset(str1245), 281},
 #endif /* USE_UNICODE_AGE_PROPERTIES */
-      {uniname2ctype_offset(str1246), 432},
+      {uniname2ctype_offset(str1246), 435},
 #ifndef USE_UNICODE_AGE_PROPERTIES
       {-1},
 #else /* USE_UNICODE_AGE_PROPERTIES */
-      {uniname2ctype_offset(str1247), 278},
+      {uniname2ctype_offset(str1247), 280},
 #endif /* USE_UNICODE_AGE_PROPERTIES */
       {uniname2ctype_offset(str1248), 30},
 #ifndef USE_UNICODE_AGE_PROPERTIES
       {-1}, {-1}, {-1}, {-1}, {-1},
 #else /* USE_UNICODE_AGE_PROPERTIES */
-      {uniname2ctype_offset(str1249), 281},
-      {uniname2ctype_offset(str1250), 294},
-      {uniname2ctype_offset(str1251), 280},
-      {uniname2ctype_offset(str1252), 282},
-      {uniname2ctype_offset(str1253), 293},
+      {uniname2ctype_offset(str1249), 283},
+      {uniname2ctype_offset(str1250), 296},
+      {uniname2ctype_offset(str1251), 282},
+      {uniname2ctype_offset(str1252), 284},
+      {uniname2ctype_offset(str1253), 295},
 #endif /* USE_UNICODE_AGE_PROPERTIES */
-      {uniname2ctype_offset(str1254), 560},
+      {uniname2ctype_offset(str1254), 566},
 #ifndef USE_UNICODE_AGE_PROPERTIES
       {-1},
 #else /* USE_UNICODE_AGE_PROPERTIES */
-      {uniname2ctype_offset(str1255), 289},
+      {uniname2ctype_offset(str1255), 291},
 #endif /* USE_UNICODE_AGE_PROPERTIES */
-      {uniname2ctype_offset(str1256), 276},
+      {uniname2ctype_offset(str1256), 278},
 #ifndef USE_UNICODE_AGE_PROPERTIES
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1263), 64},
 #else /* USE_UNICODE_AGE_PROPERTIES */
-      {uniname2ctype_offset(str1257), 288},
-      {uniname2ctype_offset(str1258), 290},
-      {uniname2ctype_offset(str1259), 292},
+      {uniname2ctype_offset(str1257), 290},
+      {uniname2ctype_offset(str1258), 292},
+      {uniname2ctype_offset(str1259), 303},
+      {uniname2ctype_offset(str1260), 294},
+      {-1},
+      {uniname2ctype_offset(str1262), 293},
 #endif /* USE_UNICODE_AGE_PROPERTIES */
-      {-1}, {-1},
-#ifdef USE_UNICODE_AGE_PROPERTIES
-      {uniname2ctype_offset(str1262), 291},
       {uniname2ctype_offset(str1263), 64},
+#ifndef USE_UNICODE_AGE_PROPERTIES
+      {-1}, {-1},
+#else /* USE_UNICODE_AGE_PROPERTIES */
       {-1},
-      {uniname2ctype_offset(str1265), 286},
+      {uniname2ctype_offset(str1265), 302},
 #endif /* USE_UNICODE_AGE_PROPERTIES */
       {uniname2ctype_offset(str1266), 21},
 #ifndef USE_UNICODE_AGE_PROPERTIES
       {-1}, {-1}, {-1}, {-1},
 #else /* USE_UNICODE_AGE_PROPERTIES */
-      {uniname2ctype_offset(str1267), 285},
-      {uniname2ctype_offset(str1268), 287},
-      {uniname2ctype_offset(str1269), 300},
+      {uniname2ctype_offset(str1267), 288},
       {-1},
+      {uniname2ctype_offset(str1269), 287},
+      {uniname2ctype_offset(str1270), 289},
 #endif /* USE_UNICODE_AGE_PROPERTIES */
-      {uniname2ctype_offset(str1271), 248},
+      {uniname2ctype_offset(str1271), 250},
+#ifndef USE_UNICODE_AGE_PROPERTIES
       {-1}, {-1},
+#else /* USE_UNICODE_AGE_PROPERTIES */
+      {-1},
+      {uniname2ctype_offset(str1273), 286},
+#endif /* USE_UNICODE_AGE_PROPERTIES */
       {uniname2ctype_offset(str1274), 200},
 #ifndef USE_UNICODE_AGE_PROPERTIES
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
 #else /* USE_UNICODE_AGE_PROPERTIES */
-      {-1}, {-1},
-      {uniname2ctype_offset(str1277), 284},
-      {-1},
-      {uniname2ctype_offset(str1279), 283},
-      {-1}, {-1},
+      {uniname2ctype_offset(str1275), 285},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
 #endif /* USE_UNICODE_AGE_PROPERTIES */
-      {uniname2ctype_offset(str1282), 626},
-      {-1},
-      {uniname2ctype_offset(str1284), 110},
+      {uniname2ctype_offset(str1282), 635},
+      {-1}, {-1},
       {uniname2ctype_offset(str1285), 105},
-      {-1},
-      {uniname2ctype_offset(str1287), 110},
-      {-1},
-      {uniname2ctype_offset(str1289), 345},
+      {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str1289), 348},
       {-1}, {-1},
-      {uniname2ctype_offset(str1292), 394},
+      {uniname2ctype_offset(str1292), 397},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1297), 145},
-      {uniname2ctype_offset(str1298), 117},
-      {-1},
+      {-1}, {-1},
       {uniname2ctype_offset(str1300), 86},
       {uniname2ctype_offset(str1301), 141},
       {-1}, {-1}, {-1}, {-1},
@@ -43277,14 +44373,11 @@ uniname2ctype_p (register const char *str, register size_t len)
       {uniname2ctype_offset(str1314), 193},
       {-1}, {-1},
       {uniname2ctype_offset(str1317), 86},
-      {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1323), 535},
-      {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1327), 117},
-      {uniname2ctype_offset(str1328), 227},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1},
-      {uniname2ctype_offset(str1330), 107},
-      {uniname2ctype_offset(str1331), 261},
+      {uniname2ctype_offset(str1328), 227},
+      {-1}, {-1},
+      {uniname2ctype_offset(str1331), 263},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1340), 105},
       {-1}, {-1},
@@ -43295,18 +44388,20 @@ uniname2ctype_p (register const char *str, register size_t len)
       {uniname2ctype_offset(str1352), 88},
       {-1},
       {uniname2ctype_offset(str1354), 164},
-      {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1358), 624},
+      {-1},
+      {uniname2ctype_offset(str1356), 605},
+      {-1},
+      {uniname2ctype_offset(str1358), 633},
       {-1},
       {uniname2ctype_offset(str1360), 3},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1365), 384},
+      {uniname2ctype_offset(str1365), 387},
       {-1},
-      {uniname2ctype_offset(str1367), 530},
+      {uniname2ctype_offset(str1367), 534},
       {-1},
-      {uniname2ctype_offset(str1369), 256},
+      {uniname2ctype_offset(str1369), 258},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1373), 272},
+      {uniname2ctype_offset(str1373), 274},
       {-1},
       {uniname2ctype_offset(str1375), 135},
       {-1}, {-1}, {-1}, {-1},
@@ -43319,29 +44414,29 @@ uniname2ctype_p (register const char *str, register size_t len)
       {uniname2ctype_offset(str1392), 138},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1400), 201},
-      {uniname2ctype_offset(str1401), 397},
+      {uniname2ctype_offset(str1401), 400},
       {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1407), 224},
       {-1},
       {uniname2ctype_offset(str1409), 38},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1415), 570},
+      {uniname2ctype_offset(str1415), 576},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1419), 140},
       {uniname2ctype_offset(str1420), 140},
       {-1},
-      {uniname2ctype_offset(str1422), 321},
+      {uniname2ctype_offset(str1422), 324},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1426), 39},
       {-1},
       {uniname2ctype_offset(str1428), 181},
       {uniname2ctype_offset(str1429), 36},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1438), 434},
+      {uniname2ctype_offset(str1438), 437},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1442), 540},
+      {uniname2ctype_offset(str1442), 544},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1448), 505},
+      {uniname2ctype_offset(str1448), 508},
       {uniname2ctype_offset(str1449), 122},
       {-1},
       {uniname2ctype_offset(str1451), 203},
@@ -43352,109 +44447,106 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1},
       {uniname2ctype_offset(str1460), 215},
       {-1},
-      {uniname2ctype_offset(str1462), 554},
+      {uniname2ctype_offset(str1462), 559},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1470), 504},
-      {uniname2ctype_offset(str1471), 506},
+      {uniname2ctype_offset(str1470), 507},
+      {uniname2ctype_offset(str1471), 509},
       {-1}, {-1},
       {uniname2ctype_offset(str1474), 134},
-      {uniname2ctype_offset(str1475), 426},
-      {uniname2ctype_offset(str1476), 508},
+      {uniname2ctype_offset(str1475), 429},
+      {uniname2ctype_offset(str1476), 511},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1480), 245},
+      {uniname2ctype_offset(str1480), 247},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1489), 33},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1495), 260},
+      {uniname2ctype_offset(str1495), 262},
       {-1},
-      {uniname2ctype_offset(str1497), 496},
+      {uniname2ctype_offset(str1497), 499},
       {-1},
-      {uniname2ctype_offset(str1499), 611},
+      {uniname2ctype_offset(str1499), 620},
       {-1},
       {uniname2ctype_offset(str1501), 196},
       {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1507), 122},
       {uniname2ctype_offset(str1508), 231},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1517), 610},
+      {uniname2ctype_offset(str1517), 619},
       {-1}, {-1},
-      {uniname2ctype_offset(str1520), 237},
+      {uniname2ctype_offset(str1520), 239},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1524), 483},
+      {uniname2ctype_offset(str1524), 486},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1529), 120},
       {-1},
-      {uniname2ctype_offset(str1531), 419},
+      {uniname2ctype_offset(str1531), 422},
       {-1},
       {uniname2ctype_offset(str1533), 142},
       {-1}, {-1},
       {uniname2ctype_offset(str1536), 127},
-      {uniname2ctype_offset(str1537), 269},
+      {uniname2ctype_offset(str1537), 271},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1542), 465},
+      {uniname2ctype_offset(str1542), 468},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1547), 168},
       {-1},
-      {uniname2ctype_offset(str1549), 519},
+      {uniname2ctype_offset(str1549), 522},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1557), 85},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1563), 273},
+      {uniname2ctype_offset(str1563), 275},
       {-1},
-      {uniname2ctype_offset(str1565), 326},
+      {uniname2ctype_offset(str1565), 329},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1570), 210},
       {-1},
       {uniname2ctype_offset(str1572), 115},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1577), 564},
+      {uniname2ctype_offset(str1577), 570},
       {-1}, {-1},
       {uniname2ctype_offset(str1580), 131},
       {-1},
       {uniname2ctype_offset(str1582), 219},
       {uniname2ctype_offset(str1583), 125},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1587), 546},
+      {uniname2ctype_offset(str1587), 550},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1597), 81},
       {uniname2ctype_offset(str1598), 219},
-      {-1}, {-1},
-      {uniname2ctype_offset(str1601), 202},
-      {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1607), 586},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str1607), 592},
       {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1613), 164},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1617), 502},
-      {uniname2ctype_offset(str1618), 272},
+      {uniname2ctype_offset(str1617), 505},
+      {uniname2ctype_offset(str1618), 274},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1622), 385},
-      {uniname2ctype_offset(str1623), 567},
+      {uniname2ctype_offset(str1622), 388},
+      {uniname2ctype_offset(str1623), 573},
       {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1629), 39},
       {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1635), 72},
-      {uniname2ctype_offset(str1636), 202},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1643), 62},
       {uniname2ctype_offset(str1644), 235},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1654), 400},
-      {uniname2ctype_offset(str1655), 274},
+      {uniname2ctype_offset(str1654), 403},
+      {uniname2ctype_offset(str1655), 276},
       {-1},
       {uniname2ctype_offset(str1657), 114},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1662), 129},
       {-1},
-      {uniname2ctype_offset(str1664), 448},
+      {uniname2ctype_offset(str1664), 451},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1671), 340},
+      {uniname2ctype_offset(str1671), 343},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1675), 469},
+      {uniname2ctype_offset(str1675), 472},
       {-1},
-      {uniname2ctype_offset(str1677), 314},
+      {uniname2ctype_offset(str1677), 317},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1682), 625},
+      {uniname2ctype_offset(str1682), 634},
       {-1},
       {uniname2ctype_offset(str1684), 199},
       {-1},
@@ -43463,186 +44555,192 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1691), 124},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1699), 379},
+      {uniname2ctype_offset(str1699), 382},
       {-1},
-      {uniname2ctype_offset(str1701), 522},
+      {uniname2ctype_offset(str1701), 525},
       {-1}, {-1},
       {uniname2ctype_offset(str1704), 207},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1714), 207},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1722), 359},
+      {uniname2ctype_offset(str1722), 362},
       {-1},
-      {uniname2ctype_offset(str1724), 576},
+      {uniname2ctype_offset(str1724), 582},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1728), 221},
-      {uniname2ctype_offset(str1729), 442},
+      {uniname2ctype_offset(str1729), 445},
       {uniname2ctype_offset(str1730), 222},
-      {uniname2ctype_offset(str1731), 534},
-      {uniname2ctype_offset(str1732), 247},
+      {uniname2ctype_offset(str1731), 538},
+      {uniname2ctype_offset(str1732), 249},
       {uniname2ctype_offset(str1733), 123},
       {uniname2ctype_offset(str1734), 114},
-      {uniname2ctype_offset(str1735), 258},
+      {uniname2ctype_offset(str1735), 260},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1740), 129},
       {-1},
       {uniname2ctype_offset(str1742), 161},
       {-1}, {-1},
-      {uniname2ctype_offset(str1745), 524},
-      {uniname2ctype_offset(str1746), 402},
+      {uniname2ctype_offset(str1745), 528},
+      {uniname2ctype_offset(str1746), 405},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1750), 20},
       {-1},
-      {uniname2ctype_offset(str1752), 516},
+      {uniname2ctype_offset(str1752), 519},
       {uniname2ctype_offset(str1753), 148},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1757), 515},
+      {uniname2ctype_offset(str1757), 518},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1766), 73},
       {-1},
       {uniname2ctype_offset(str1768), 148},
-      {uniname2ctype_offset(str1769), 374},
+      {uniname2ctype_offset(str1769), 377},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1776), 126},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1781), 552},
+      {uniname2ctype_offset(str1781), 556},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1788), 97},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1793), 97},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1806), 348},
+      {uniname2ctype_offset(str1806), 351},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1810), 630},
-      {uniname2ctype_offset(str1811), 245},
+      {uniname2ctype_offset(str1810), 640},
+      {uniname2ctype_offset(str1811), 247},
       {-1},
-      {uniname2ctype_offset(str1813), 264},
+      {uniname2ctype_offset(str1813), 266},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1821), 224},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1828), 399},
+      {uniname2ctype_offset(str1828), 402},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1838), 614},
+      {uniname2ctype_offset(str1838), 623},
       {-1}, {-1},
-      {uniname2ctype_offset(str1841), 457},
-      {uniname2ctype_offset(str1842), 391},
+      {uniname2ctype_offset(str1841), 460},
+      {uniname2ctype_offset(str1842), 394},
       {uniname2ctype_offset(str1843), 65},
       {-1},
-      {uniname2ctype_offset(str1845), 263},
+      {uniname2ctype_offset(str1845), 265},
       {-1}, {-1},
       {uniname2ctype_offset(str1848), 109},
       {-1}, {-1},
       {uniname2ctype_offset(str1851), 137},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1857), 244},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1866), 61},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1871), 491},
+      {uniname2ctype_offset(str1871), 494},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1881), 63},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1888), 527},
-      {uniname2ctype_offset(str1889), 551},
+      {uniname2ctype_offset(str1888), 531},
+      {uniname2ctype_offset(str1889), 555},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1896), 617},
+      {uniname2ctype_offset(str1896), 626},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1902), 431},
+      {uniname2ctype_offset(str1902), 434},
       {-1},
-      {uniname2ctype_offset(str1904), 452},
-      {uniname2ctype_offset(str1905), 584},
+      {uniname2ctype_offset(str1904), 455},
+      {uniname2ctype_offset(str1905), 590},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1912), 580},
+      {uniname2ctype_offset(str1912), 586},
       {uniname2ctype_offset(str1913), 143},
       {-1}, {-1},
-      {uniname2ctype_offset(str1916), 588},
+      {uniname2ctype_offset(str1916), 594},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1924), 143},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1929), 429},
+      {uniname2ctype_offset(str1929), 432},
       {-1}, {-1},
-      {uniname2ctype_offset(str1932), 412},
+      {uniname2ctype_offset(str1932), 415},
       {-1}, {-1},
-      {uniname2ctype_offset(str1935), 262},
-      {uniname2ctype_offset(str1936), 335},
+      {uniname2ctype_offset(str1935), 264},
+      {uniname2ctype_offset(str1936), 338},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1941), 27},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1948), 87},
-      {-1},
-      {uniname2ctype_offset(str1950), 421},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str1950), 424},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1956), 250},
-      {uniname2ctype_offset(str1957), 87},
+      {uniname2ctype_offset(str1956), 252},
+      {-1},
       {uniname2ctype_offset(str1958), 109},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1964), 437},
+      {uniname2ctype_offset(str1964), 440},
       {-1}, {-1},
-      {uniname2ctype_offset(str1967), 489},
-      {uniname2ctype_offset(str1968), 634},
-      {uniname2ctype_offset(str1969), 249},
+      {uniname2ctype_offset(str1967), 492},
+      {uniname2ctype_offset(str1968), 644},
+      {uniname2ctype_offset(str1969), 251},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1974), 355},
+      {uniname2ctype_offset(str1974), 358},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str1981), 176},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str1985), 405},
+      {uniname2ctype_offset(str1985), 408},
       {-1}, {-1},
-      {uniname2ctype_offset(str1988), 438},
+      {uniname2ctype_offset(str1988), 441},
       {-1}, {-1},
       {uniname2ctype_offset(str1991), 1},
       {-1},
-      {uniname2ctype_offset(str1993), 372},
+      {uniname2ctype_offset(str1993), 375},
       {uniname2ctype_offset(str1994), 175},
       {-1},
       {uniname2ctype_offset(str1996), 42},
-      {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2002), 591},
-      {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2006), 407},
-      {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2010), 375},
-      {uniname2ctype_offset(str2011), 267},
-      {uniname2ctype_offset(str2012), 559},
+      {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str2001), 110},
+      {uniname2ctype_offset(str2002), 598},
       {-1},
-      {uniname2ctype_offset(str2014), 333},
+      {uniname2ctype_offset(str2004), 110},
+      {-1},
+      {uniname2ctype_offset(str2006), 410},
+      {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str2010), 378},
+      {uniname2ctype_offset(str2011), 269},
+      {uniname2ctype_offset(str2012), 565},
       {-1},
+      {uniname2ctype_offset(str2014), 336},
+      {uniname2ctype_offset(str2015), 117},
       {uniname2ctype_offset(str2016), 209},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2023), 32},
-      {uniname2ctype_offset(str2024), 503},
+      {uniname2ctype_offset(str2024), 506},
       {-1},
       {uniname2ctype_offset(str2026), 176},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2033), 8},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str2040), 539},
+      {-1},
       {uniname2ctype_offset(str2042), 121},
       {uniname2ctype_offset(str2043), 17},
+      {uniname2ctype_offset(str2044), 117},
+      {-1}, {-1},
+      {uniname2ctype_offset(str2047), 107},
+      {uniname2ctype_offset(str2048), 526},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2062), 130},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2070), 9},
       {-1}, {-1},
-      {uniname2ctype_offset(str2073), 342},
+      {uniname2ctype_offset(str2073), 345},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2077), 150},
-      {uniname2ctype_offset(str2078), 254},
+      {uniname2ctype_offset(str2078), 256},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1},
-      {uniname2ctype_offset(str2090), 275},
+      {uniname2ctype_offset(str2090), 277},
       {-1},
       {uniname2ctype_offset(str2092), 150},
       {-1}, {-1},
-      {uniname2ctype_offset(str2095), 353},
+      {uniname2ctype_offset(str2095), 356},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2103), 162},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2110), 123},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2114), 436},
-      {uniname2ctype_offset(str2115), 381},
+      {uniname2ctype_offset(str2114), 439},
+      {uniname2ctype_offset(str2115), 384},
       {-1},
       {uniname2ctype_offset(str2117), 174},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
@@ -43653,15 +44751,15 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1},
       {uniname2ctype_offset(str2137), 12},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2141), 242},
+      {uniname2ctype_offset(str2141), 244},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2145), 52},
-      {uniname2ctype_offset(str2146), 413},
+      {uniname2ctype_offset(str2146), 416},
       {-1}, {-1},
       {uniname2ctype_offset(str2149), 221},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2163), 249},
+      {uniname2ctype_offset(str2163), 251},
       {-1},
       {uniname2ctype_offset(str2165), 174},
       {uniname2ctype_offset(str2166), 5},
@@ -43674,107 +44772,100 @@ uniname2ctype_p (register const char *str, register size_t len)
       {uniname2ctype_offset(str2182), 216},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2195), 351},
-      {uniname2ctype_offset(str2196), 493},
+      {uniname2ctype_offset(str2195), 354},
+      {uniname2ctype_offset(str2196), 496},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1},
       {uniname2ctype_offset(str2207), 196},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2211), 20},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2216), 364},
+      {uniname2ctype_offset(str2216), 367},
       {uniname2ctype_offset(str2217), 128},
-      {uniname2ctype_offset(str2218), 543},
+      {uniname2ctype_offset(str2218), 547},
       {uniname2ctype_offset(str2219), 78},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2224), 450},
+      {uniname2ctype_offset(str2224), 453},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2228), 43},
       {uniname2ctype_offset(str2229), 35},
       {-1}, {-1},
-      {uniname2ctype_offset(str2232), 382},
+      {uniname2ctype_offset(str2232), 385},
       {uniname2ctype_offset(str2233), 216},
       {uniname2ctype_offset(str2234), 92},
-      {uniname2ctype_offset(str2235), 486},
+      {uniname2ctype_offset(str2235), 489},
       {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2241), 92},
       {-1}, {-1},
-      {uniname2ctype_offset(str2244), 440},
+      {uniname2ctype_offset(str2244), 443},
       {-1}, {-1},
       {uniname2ctype_offset(str2247), 36},
-      {uniname2ctype_offset(str2248), 595},
+      {uniname2ctype_offset(str2248), 602},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2276), 415},
+      {uniname2ctype_offset(str2276), 418},
       {-1},
       {uniname2ctype_offset(str2278), 124},
       {uniname2ctype_offset(str2279), 192},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2283), 214},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str2296), 639},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2305), 205},
       {-1}, {-1},
       {uniname2ctype_offset(str2308), 234},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2312), 177},
       {-1}, {-1},
-      {uniname2ctype_offset(str2315), 594},
-      {uniname2ctype_offset(str2316), 629},
-      {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str2315), 601},
+      {uniname2ctype_offset(str2316), 638},
+      {-1},
+      {uniname2ctype_offset(str2318), 202},
+      {-1}, {-1},
       {uniname2ctype_offset(str2321), 153},
       {-1},
       {uniname2ctype_offset(str2323), 172},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2327), 378},
+      {uniname2ctype_offset(str2327), 381},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2331), 627},
+      {uniname2ctype_offset(str2331), 636},
       {-1},
       {uniname2ctype_offset(str2333), 134},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2341), 185},
-      {-1},
-      {uniname2ctype_offset(str2343), 585},
-      {uniname2ctype_offset(str2344), 439},
-      {uniname2ctype_offset(str2345), 239},
-      {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2350), 185},
-      {uniname2ctype_offset(str2351), 99},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2361), 598},
-      {-1}, {-1},
-      {uniname2ctype_offset(str2364), 320},
-      {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2370), 339},
+      {uniname2ctype_offset(str2343), 591},
+      {uniname2ctype_offset(str2344), 442},
+      {uniname2ctype_offset(str2345), 241},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str2353), 202},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str2361), 606},
       {-1}, {-1},
+      {uniname2ctype_offset(str2364), 323},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2373), 37},
-      {uniname2ctype_offset(str2374), 389},
+      {uniname2ctype_offset(str2374), 392},
       {uniname2ctype_offset(str2375), 197},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2389), 557},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2397), 418},
-      {uniname2ctype_offset(str2398), 410},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str2397), 421},
+      {uniname2ctype_offset(str2398), 413},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2405), 165},
-      {uniname2ctype_offset(str2406), 107},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2414), 82},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2418), 449},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2427), 23},
-      {uniname2ctype_offset(str2428), 183},
-      {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2433), 336},
+      {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str2433), 339},
       {uniname2ctype_offset(str2434), 154},
       {-1}, {-1},
       {uniname2ctype_offset(str2437), 194},
-      {uniname2ctype_offset(str2438), 182},
-      {-1},
+      {-1}, {-1},
       {uniname2ctype_offset(str2440), 100},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1},
@@ -43782,36 +44873,36 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1},
       {uniname2ctype_offset(str2454), 220},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2460), 255},
+      {uniname2ctype_offset(str2460), 257},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2464), 159},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2470), 445},
+      {uniname2ctype_offset(str2470), 448},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2475), 142},
-      {uniname2ctype_offset(str2476), 430},
+      {uniname2ctype_offset(str2476), 558},
       {-1},
-      {uniname2ctype_offset(str2478), 414},
-      {uniname2ctype_offset(str2479), 358},
+      {uniname2ctype_offset(str2478), 417},
+      {uniname2ctype_offset(str2479), 361},
       {-1},
-      {uniname2ctype_offset(str2481), 383},
+      {uniname2ctype_offset(str2481), 386},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2500), 121},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2506), 528},
+      {uniname2ctype_offset(str2506), 532},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2511), 242},
+      {uniname2ctype_offset(str2511), 244},
       {-1},
-      {uniname2ctype_offset(str2513), 621},
+      {uniname2ctype_offset(str2513), 630},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2530), 82},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2534), 337},
+      {uniname2ctype_offset(str2534), 340},
+      {uniname2ctype_offset(str2535), 237},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1},
-      {uniname2ctype_offset(str2545), 275},
+      {uniname2ctype_offset(str2545), 277},
       {-1}, {-1},
       {uniname2ctype_offset(str2548), 118},
       {uniname2ctype_offset(str2549), 159},
@@ -43819,74 +44910,74 @@ uniname2ctype_p (register const char *str, register size_t len)
       {uniname2ctype_offset(str2551), 89},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2564), 369},
+      {uniname2ctype_offset(str2564), 372},
       {-1}, {-1},
-      {uniname2ctype_offset(str2567), 315},
+      {uniname2ctype_offset(str2567), 318},
       {-1}, {-1},
-      {uniname2ctype_offset(str2570), 488},
+      {uniname2ctype_offset(str2570), 491},
       {-1},
-      {uniname2ctype_offset(str2572), 470},
-      {-1}, {-1},
-      {uniname2ctype_offset(str2575), 471},
-      {uniname2ctype_offset(str2576), 273},
+      {uniname2ctype_offset(str2572), 473},
+      {-1},
+      {uniname2ctype_offset(str2574), 246},
+      {uniname2ctype_offset(str2575), 474},
+      {uniname2ctype_offset(str2576), 275},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2582), 388},
+      {uniname2ctype_offset(str2582), 391},
       {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2588), 154},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2602), 210},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2606), 371},
+      {uniname2ctype_offset(str2606), 374},
       {-1},
-      {uniname2ctype_offset(str2608), 455},
+      {uniname2ctype_offset(str2608), 458},
       {uniname2ctype_offset(str2609), 55},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2625), 260},
+      {uniname2ctype_offset(str2625), 262},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2648), 252},
+      {uniname2ctype_offset(str2648), 254},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2652), 380},
+      {uniname2ctype_offset(str2652), 383},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2656), 365},
+      {uniname2ctype_offset(str2656), 368},
       {uniname2ctype_offset(str2657), 112},
-      {-1}, {-1},
-      {uniname2ctype_offset(str2660), 147},
-      {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str2665), 87},
       {uniname2ctype_offset(str2666), 50},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2670), 623},
+      {uniname2ctype_offset(str2670), 632},
+      {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str2674), 87},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2688), 139},
-      {uniname2ctype_offset(str2689), 631},
+      {uniname2ctype_offset(str2689), 641},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2694), 48},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1},
-      {uniname2ctype_offset(str2705), 478},
+      {uniname2ctype_offset(str2705), 481},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1},
       {uniname2ctype_offset(str2726), 226},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1},
-      {uniname2ctype_offset(str2738), 225},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1},
-      {uniname2ctype_offset(str2750), 553},
+      {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str2750), 557},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1},
       {uniname2ctype_offset(str2761), 18},
-      {uniname2ctype_offset(str2762), 263},
+      {uniname2ctype_offset(str2762), 265},
       {-1}, {-1},
       {uniname2ctype_offset(str2765), 133},
       {uniname2ctype_offset(str2766), 54},
       {-1}, {-1},
-      {uniname2ctype_offset(str2769), 480},
+      {uniname2ctype_offset(str2769), 483},
       {-1}, {-1},
       {uniname2ctype_offset(str2772), 199},
       {-1}, {-1},
@@ -43894,94 +44985,87 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1},
       {uniname2ctype_offset(str2786), 4},
-      {uniname2ctype_offset(str2787), 80},
-      {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2793), 34},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2801), 29},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2808), 509},
+      {uniname2ctype_offset(str2808), 512},
       {-1},
       {uniname2ctype_offset(str2810), 226},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2816), 307},
+      {uniname2ctype_offset(str2816), 310},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2821), 390},
+      {uniname2ctype_offset(str2821), 393},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2830), 605},
+      {uniname2ctype_offset(str2830), 614},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2834), 361},
+      {uniname2ctype_offset(str2834), 364},
       {-1},
       {uniname2ctype_offset(str2836), 78},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1},
-      {uniname2ctype_offset(str2847), 246},
+      {uniname2ctype_offset(str2847), 248},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2852), 302},
+      {uniname2ctype_offset(str2852), 305},
       {-1}, {-1},
       {uniname2ctype_offset(str2855), 190},
       {uniname2ctype_offset(str2856), 66},
       {-1}, {-1},
-      {uniname2ctype_offset(str2859), 424},
+      {uniname2ctype_offset(str2859), 427},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2867), 306},
-      {uniname2ctype_offset(str2868), 246},
+      {uniname2ctype_offset(str2867), 309},
+      {uniname2ctype_offset(str2868), 248},
       {-1}, {-1},
-      {uniname2ctype_offset(str2871), 252},
+      {uniname2ctype_offset(str2871), 254},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2879), 204},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2886), 622},
+      {uniname2ctype_offset(str2886), 631},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2901), 99},
-      {uniname2ctype_offset(str2902), 474},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str2902), 477},
       {-1},
-      {uniname2ctype_offset(str2904), 461},
-      {uniname2ctype_offset(str2905), 271},
+      {uniname2ctype_offset(str2904), 464},
+      {uniname2ctype_offset(str2905), 273},
       {-1},
-      {uniname2ctype_offset(str2907), 271},
+      {uniname2ctype_offset(str2907), 273},
       {-1},
-      {uniname2ctype_offset(str2909), 571},
+      {uniname2ctype_offset(str2909), 577},
       {-1},
-      {uniname2ctype_offset(str2911), 447},
+      {uniname2ctype_offset(str2911), 450},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1},
-      {uniname2ctype_offset(str2941), 360},
+      {uniname2ctype_offset(str2941), 363},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1},
       {uniname2ctype_offset(str2953), 198},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1},
-      {uniname2ctype_offset(str2964), 517},
+      {uniname2ctype_offset(str2964), 520},
       {-1},
-      {uniname2ctype_offset(str2966), 236},
+      {uniname2ctype_offset(str2966), 238},
       {uniname2ctype_offset(str2967), 43},
-      {-1},
-      {uniname2ctype_offset(str2969), 204},
+      {-1}, {-1},
       {uniname2ctype_offset(str2970), 88},
-      {-1},
-      {uniname2ctype_offset(str2972), 244},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str2980), 195},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2984), 568},
+      {uniname2ctype_offset(str2984), 574},
       {-1},
       {uniname2ctype_offset(str2986), 118},
       {uniname2ctype_offset(str2987), 54},
-      {uniname2ctype_offset(str2988), 468},
-      {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2993), 201},
-      {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str2997), 596},
+      {uniname2ctype_offset(str2988), 471},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str2997), 603},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3001), 180},
       {uniname2ctype_offset(str3002), 64},
       {-1}, {-1},
-      {uniname2ctype_offset(str3005), 472},
-      {uniname2ctype_offset(str3006), 577},
+      {uniname2ctype_offset(str3005), 475},
+      {uniname2ctype_offset(str3006), 583},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3015), 83},
       {-1}, {-1},
@@ -43989,60 +45073,73 @@ uniname2ctype_p (register const char *str, register size_t len)
       {uniname2ctype_offset(str3019), 165},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3026), 83},
-      {uniname2ctype_offset(str3027), 500},
+      {uniname2ctype_offset(str3027), 503},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3035), 232},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3042), 211},
       {-1}, {-1},
-      {uniname2ctype_offset(str3045), 606},
+      {uniname2ctype_offset(str3045), 615},
       {-1}, {-1},
       {uniname2ctype_offset(str3048), 119},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3052), 89},
       {uniname2ctype_offset(str3053), 229},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3058), 185},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3067), 185},
+      {uniname2ctype_offset(str3068), 99},
+      {-1}, {-1},
       {uniname2ctype_offset(str3071), 198},
       {uniname2ctype_offset(str3072), 133},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3082), 130},
-      {-1}, {-1}, {-1},
+      {-1},
+      {uniname2ctype_offset(str3084), 237},
+      {-1},
       {uniname2ctype_offset(str3086), 84},
-      {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3091), 259},
+      {uniname2ctype_offset(str3087), 342},
+      {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3091), 261},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3099), 475},
+      {uniname2ctype_offset(str3099), 478},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3104), 84},
-      {-1}, {-1},
-      {uniname2ctype_offset(str3107), 310},
       {-1},
-      {uniname2ctype_offset(str3109), 312},
+      {uniname2ctype_offset(str3106), 562},
+      {uniname2ctype_offset(str3107), 313},
+      {-1},
+      {uniname2ctype_offset(str3109), 315},
       {uniname2ctype_offset(str3110), 152},
       {uniname2ctype_offset(str3111), 191},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3118), 90},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3123), 107},
+      {-1},
       {uniname2ctype_offset(str3125), 191},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3140), 607},
-      {-1},
-      {uniname2ctype_offset(str3142), 579},
+      {uniname2ctype_offset(str3135), 452},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3142), 585},
+      {-1}, {-1},
+      {uniname2ctype_offset(str3145), 183},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3155), 182},
+      {-1},
       {uniname2ctype_offset(str3157), 231},
-      {uniname2ctype_offset(str3158), 325},
+      {uniname2ctype_offset(str3158), 328},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3176), 393},
+      {uniname2ctype_offset(str3176), 396},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3180), 328},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3180), 331},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3193), 433},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3209), 62},
       {-1}, {-1},
       {uniname2ctype_offset(str3212), 211},
@@ -44050,97 +45147,97 @@ uniname2ctype_p (register const char *str, register size_t len)
       {uniname2ctype_offset(str3215), 180},
       {-1}, {-1},
       {uniname2ctype_offset(str3218), 125},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3227), 433},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3237), 387},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3237), 390},
       {-1},
-      {uniname2ctype_offset(str3239), 305},
-      {uniname2ctype_offset(str3240), 301},
+      {uniname2ctype_offset(str3239), 308},
+      {uniname2ctype_offset(str3240), 304},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3248), 213},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3254), 250},
+      {uniname2ctype_offset(str3254), 252},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1},
-      {uniname2ctype_offset(str3265), 601},
+      {uniname2ctype_offset(str3265), 610},
       {-1},
       {uniname2ctype_offset(str3267), 28},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3275), 146},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3284), 609},
+      {uniname2ctype_offset(str3284), 618},
       {-1}, {-1},
       {uniname2ctype_offset(str3287), 223},
-      {-1}, {-1},
-      {uniname2ctype_offset(str3290), 451},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3297), 308},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3297), 311},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3303), 304},
+      {uniname2ctype_offset(str3303), 307},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3313), 253},
+      {uniname2ctype_offset(str3313), 255},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3320), 223},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3328), 63},
-      {uniname2ctype_offset(str3329), 616},
+      {uniname2ctype_offset(str3329), 625},
       {-1},
       {uniname2ctype_offset(str3331), 222},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3338), 262},
+      {uniname2ctype_offset(str3338), 264},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3348), 404},
+      {uniname2ctype_offset(str3348), 407},
       {-1},
-      {uniname2ctype_offset(str3350), 498},
+      {uniname2ctype_offset(str3350), 501},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3355), 47},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3360), 334},
+      {uniname2ctype_offset(str3360), 337},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1},
       {uniname2ctype_offset(str3371), 126},
       {uniname2ctype_offset(str3372), 16},
-      {uniname2ctype_offset(str3373), 251},
+      {uniname2ctype_offset(str3373), 253},
+      {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3377), 147},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3391), 236},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3396), 604},
+      {uniname2ctype_offset(str3391), 238},
+      {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3396), 613},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3405), 466},
+      {uniname2ctype_offset(str3405), 469},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1},
       {uniname2ctype_offset(str3416), 51},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1},
-      {uniname2ctype_offset(str3428), 251},
+      {uniname2ctype_offset(str3428), 253},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3433), 205},
       {-1}, {-1},
       {uniname2ctype_offset(str3436), 213},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3452), 220},
-      {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3455), 225},
+      {-1}, {-1},
       {uniname2ctype_offset(str3458), 10},
       {-1},
-      {uniname2ctype_offset(str3460), 618},
+      {uniname2ctype_offset(str3460), 627},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3483), 243},
+      {uniname2ctype_offset(str3483), 245},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3502), 49},
-      {-1}, {-1},
-      {uniname2ctype_offset(str3505), 476},
+      {-1},
+      {uniname2ctype_offset(str3504), 80},
+      {uniname2ctype_offset(str3505), 479},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3511), 408},
+      {uniname2ctype_offset(str3511), 411},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1},
-      {uniname2ctype_offset(str3532), 572},
+      {uniname2ctype_offset(str3532), 578},
       {uniname2ctype_offset(str3533), 57},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
@@ -44156,11 +45253,13 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3613), 41},
+      {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3618), 99},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3648), 462},
+      {-1}, {-1},
+      {uniname2ctype_offset(str3648), 465},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1},
       {uniname2ctype_offset(str3659), 178},
@@ -44168,18 +45267,23 @@ uniname2ctype_p (register const char *str, register size_t len)
       {uniname2ctype_offset(str3664), 177},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3698), 501},
-      {uniname2ctype_offset(str3699), 548},
+      {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3686), 204},
+      {-1}, {-1},
+      {uniname2ctype_offset(str3689), 246},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3698), 504},
+      {uniname2ctype_offset(str3699), 552},
       {-1},
       {uniname2ctype_offset(str3701), 96},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3705), 317},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3705), 320},
+      {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3710), 201},
+      {-1}, {-1},
       {uniname2ctype_offset(str3713), 96},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3721), 435},
+      {uniname2ctype_offset(str3721), 438},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1},
@@ -44188,57 +45292,59 @@ uniname2ctype_p (register const char *str, register size_t len)
       {uniname2ctype_offset(str3754), 71},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1},
-      {uniname2ctype_offset(str3766), 464},
-      {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3770), 147},
+      {uniname2ctype_offset(str3766), 467},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1},
+      {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3799), 214},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3807), 258},
+      {uniname2ctype_offset(str3807), 260},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3842), 182},
       {-1}, {-1},
-      {uniname2ctype_offset(str3845), 257},
+      {uniname2ctype_offset(str3845), 259},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3850), 243},
+      {uniname2ctype_offset(str3850), 245},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3854), 65},
+      {-1}, {-1},
+      {uniname2ctype_offset(str3857), 616},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3868), 259},
+      {-1},
+      {uniname2ctype_offset(str3868), 261},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3881), 228},
       {-1}, {-1},
-      {uniname2ctype_offset(str3884), 303},
+      {uniname2ctype_offset(str3884), 306},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3891), 30},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3924), 417},
+      {uniname2ctype_offset(str3924), 420},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str3942), 100},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3949), 274},
+      {-1},
+      {uniname2ctype_offset(str3944), 436},
+      {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3949), 276},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str3976), 597},
-      {-1},
-      {uniname2ctype_offset(str3978), 80},
+      {uniname2ctype_offset(str3976), 604},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1},
-      {uniname2ctype_offset(str3998), 427},
+      {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str3998), 430},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str4007), 454},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
@@ -44246,13 +45352,10 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str4066), 313},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str4106), 45},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str4116), 132},
@@ -44263,14 +45366,15 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str4169), 220},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str4231), 153},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
@@ -44281,18 +45385,17 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str4308), 398},
+      {uniname2ctype_offset(str4308), 401},
       {uniname2ctype_offset(str4309), 162},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1},
-      {uniname2ctype_offset(str4321), 240},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str4348), 565},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1},
+      {uniname2ctype_offset(str4348), 571},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str4361), 566},
+      {uniname2ctype_offset(str4361), 572},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
@@ -44308,6 +45411,7 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str4487), 147},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
@@ -44320,42 +45424,45 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str4604), 116},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1},
       {uniname2ctype_offset(str4626), 116},
-      {uniname2ctype_offset(str4627), 253},
+      {uniname2ctype_offset(str4627), 255},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1},
-      {uniname2ctype_offset(str4674), 632},
+      {uniname2ctype_offset(str4674), 642},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str4683), 463},
+      {uniname2ctype_offset(str4683), 466},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1},
+      {uniname2ctype_offset(str4695), 80},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1}, {-1},
       {uniname2ctype_offset(str4734), 179},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1},
-      {uniname2ctype_offset(str4755), 309},
-      {uniname2ctype_offset(str4756), 311},
+      {uniname2ctype_offset(str4755), 312},
+      {uniname2ctype_offset(str4756), 314},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str4772), 406},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str4772), 409},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1},
+      {uniname2ctype_offset(str4783), 316},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1},
+      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {uniname2ctype_offset(str4810), 90},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
@@ -44380,7 +45487,7 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1},
       {uniname2ctype_offset(str4982), 232},
       {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str4986), 425},
+      {uniname2ctype_offset(str4986), 428},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
@@ -44388,6 +45495,8 @@ uniname2ctype_p (register const char *str, register size_t len)
       {uniname2ctype_offset(str5018), 46},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
+      {-1},
+      {uniname2ctype_offset(str5038), 242},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
@@ -44398,8 +45507,8 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str5134), 619},
+      {-1}, {-1}, {-1}, {-1}, {-1},
+      {uniname2ctype_offset(str5134), 628},
 #endif /* USE_UNICODE_PROPERTIES */
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
 #ifndef USE_UNICODE_PROPERTIES
@@ -44529,7 +45638,7 @@ uniname2ctype_p (register const char *str, register size_t len)
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
-      {uniname2ctype_offset(str6098), 633}
+      {uniname2ctype_offset(str6098), 643}
 #endif /* USE_UNICODE_PROPERTIES */
     };
 
@@ -44560,22 +45669,22 @@ uniname2ctype(const UChar *name, unsigned int len)
   return -1;
 }
 #if defined ONIG_UNICODE_VERSION_STRING && !( \
-      ONIG_UNICODE_VERSION_MAJOR == 14 && \
+      ONIG_UNICODE_VERSION_MAJOR == 15 && \
       ONIG_UNICODE_VERSION_MINOR == 0 && \
       ONIG_UNICODE_VERSION_TEENY == 0 && \
       1)
 # error ONIG_UNICODE_VERSION_STRING mismatch
 #endif
-#define ONIG_UNICODE_VERSION_STRING "14.0.0"
-#define ONIG_UNICODE_VERSION_MAJOR 14
+#define ONIG_UNICODE_VERSION_STRING "15.0.0"
+#define ONIG_UNICODE_VERSION_MAJOR 15
 #define ONIG_UNICODE_VERSION_MINOR 0
 #define ONIG_UNICODE_VERSION_TEENY 0
 #if defined ONIG_UNICODE_EMOJI_VERSION_STRING && !( \
-      ONIG_UNICODE_EMOJI_VERSION_MAJOR == 14 && \
+      ONIG_UNICODE_EMOJI_VERSION_MAJOR == 15 && \
       ONIG_UNICODE_EMOJI_VERSION_MINOR == 0 && \
       1)
 # error ONIG_UNICODE_EMOJI_VERSION_STRING mismatch
 #endif
-#define ONIG_UNICODE_EMOJI_VERSION_STRING "14.0"
-#define ONIG_UNICODE_EMOJI_VERSION_MAJOR 14
+#define ONIG_UNICODE_EMOJI_VERSION_STRING "15.0"
+#define ONIG_UNICODE_EMOJI_VERSION_MAJOR 15
 #define ONIG_UNICODE_EMOJI_VERSION_MINOR 0
diff --git a/enc/utf_16_32.h b/enc/utf_16_32.h
index 9f9216d8ff..4d669019bf 100644
--- a/enc/utf_16_32.h
+++ b/enc/utf_16_32.h
@@ -1,5 +1,5 @@
 #include "regenc.h"
 /* dummy for unsupported, stateful encoding */
-#define ENC_DUMMY_UNICODE(name) ENC_REPLICATE(name, name "BE")
+#define ENC_DUMMY_UNICODE(name) ENC_DUMMY(name)
 ENC_DUMMY_UNICODE("UTF-16");
 ENC_DUMMY_UNICODE("UTF-32");
diff --git a/encindex.h b/encindex.h
index 8457a7b39f..e6ddb1b0c2 100644
--- a/encindex.h
+++ b/encindex.h
@@ -20,7 +20,7 @@ extern "C" {
 #endif
 
 enum ruby_preserved_encindex {
-    RUBY_ENCINDEX_ASCII,
+    RUBY_ENCINDEX_ASCII_8BIT,
     RUBY_ENCINDEX_UTF_8,
     RUBY_ENCINDEX_US_ASCII,
 
@@ -40,7 +40,7 @@ enum ruby_preserved_encindex {
     RUBY_ENCINDEX_BUILTIN_MAX
 };
 
-#define ENCINDEX_ASCII       RUBY_ENCINDEX_ASCII
+#define ENCINDEX_ASCII_8BIT  RUBY_ENCINDEX_ASCII_8BIT
 #define ENCINDEX_UTF_8       RUBY_ENCINDEX_UTF_8
 #define ENCINDEX_US_ASCII    RUBY_ENCINDEX_US_ASCII
 #define ENCINDEX_UTF_16BE    RUBY_ENCINDEX_UTF_16BE
@@ -54,7 +54,7 @@ enum ruby_preserved_encindex {
 #define ENCINDEX_Windows_31J RUBY_ENCINDEX_Windows_31J
 #define ENCINDEX_BUILTIN_MAX RUBY_ENCINDEX_BUILTIN_MAX
 
-#define rb_ascii8bit_encindex() RUBY_ENCINDEX_ASCII
+#define rb_ascii8bit_encindex() RUBY_ENCINDEX_ASCII_8BIT
 #define rb_utf8_encindex()      RUBY_ENCINDEX_UTF_8
 #define rb_usascii_encindex()   RUBY_ENCINDEX_US_ASCII
 
diff --git a/encoding.c b/encoding.c
index 876b03e36f..2f4b47bdfa 100644
--- a/encoding.c
+++ b/encoding.c
@@ -17,6 +17,7 @@
 #include "internal.h"
 #include "internal/enc.h"
 #include "internal/encoding.h"
+#include "internal/error.h"
 #include "internal/inits.h"
 #include "internal/load.h"
 #include "internal/object.h"
@@ -49,16 +50,14 @@ void rb_encdb_declare(const char *name);
 int rb_encdb_replicate(const char *name, const char *orig);
 int rb_encdb_dummy(const char *name);
 int rb_encdb_alias(const char *alias, const char *orig);
-void rb_encdb_set_unicode(int index);
 #pragma GCC visibility pop
 #endif
 
 static ID id_encoding;
 VALUE rb_cEncoding;
 
-#define DEFAULT_ENCODING_LIST_CAPA 128
-static VALUE rb_default_encoding_list;
-static VALUE rb_additional_encoding_list;
+#define ENCODING_LIST_CAPA 256
+static VALUE rb_encoding_list;
 
 struct rb_encoding_entry {
     const char *name;
@@ -67,9 +66,8 @@ struct rb_encoding_entry {
 };
 
 static struct enc_table {
-    struct rb_encoding_entry *list;
+    struct rb_encoding_entry list[ENCODING_LIST_CAPA];
     int count;
-    int size;
     st_table *names;
 } global_enc_table;
 
@@ -128,47 +126,25 @@ enc_new(rb_encoding *encoding)
 static void
 enc_list_update(int index, rb_raw_encoding *encoding)
 {
-    if (index < DEFAULT_ENCODING_LIST_CAPA) {
-        VALUE list = rb_default_encoding_list;
-        if (list && NIL_P(rb_ary_entry(list, index))) {
-            /* initialize encoding data */
-            rb_ary_store(list, index, enc_new(encoding));
-        }
-    }
-    else {
-        RB_VM_LOCK_ENTER();
-        {
-            VALUE list = rb_additional_encoding_list;
-            if (list && NIL_P(rb_ary_entry(list, index))) {
-                /* initialize encoding data */
-                rb_ary_store(list, index - DEFAULT_ENCODING_LIST_CAPA, enc_new(encoding));
-            }
-        }
-        RB_VM_LOCK_LEAVE();
+    RUBY_ASSERT(index < ENCODING_LIST_CAPA);
+
+    VALUE list = rb_encoding_list;
+    if (list && NIL_P(rb_ary_entry(list, index))) {
+        /* initialize encoding data */
+        rb_ary_store(list, index, enc_new(encoding));
     }
 }
 
 static VALUE
 enc_list_lookup(int idx)
 {
-    VALUE list, enc;
+    VALUE list, enc = Qnil;
 
-    if (idx < DEFAULT_ENCODING_LIST_CAPA) {
-        if (!(list = rb_default_encoding_list)) {
-            rb_bug("rb_enc_from_encoding_index(%d): no rb_default_encoding_list", idx);
-        }
+    if (idx < ENCODING_LIST_CAPA) {
+        list = rb_encoding_list;
+        RUBY_ASSERT(list);
         enc = rb_ary_entry(list, idx);
     }
-    else {
-        RB_VM_LOCK_ENTER();
-        {
-            if (!(list = rb_additional_encoding_list)) {
-                rb_bug("rb_enc_from_encoding_index(%d): no rb_additional_encoding_list", idx);
-            }
-            enc = rb_ary_entry(list, idx - DEFAULT_ENCODING_LIST_CAPA);
-        }
-        RB_VM_LOCK_LEAVE();
-    }
 
     if (NIL_P(enc)) {
         rb_bug("rb_enc_from_encoding_index(%d): not created yet", idx);
@@ -210,7 +186,7 @@ check_encoding(rb_encoding *enc)
 {
     int index = rb_enc_to_index(enc);
     if (rb_enc_from_index(index) != enc)
-	return -1;
+        return -1;
     if (rb_enc_autoload_p(enc)) {
         index = rb_enc_autoload(enc);
     }
@@ -221,7 +197,7 @@ static int
 enc_check_encoding(VALUE obj)
 {
     if (!is_obj_encoding(obj)) {
-	return -1;
+        return -1;
     }
     return check_encoding(RDATA(obj)->data);
 }
@@ -231,7 +207,7 @@ static void
 not_encoding(VALUE enc)
 {
     rb_raise(rb_eTypeError, "wrong argument type %"PRIsVALUE" (expected Encoding)",
-	     rb_obj_class(enc));
+             rb_obj_class(enc));
 }
 
 static rb_encoding *
@@ -239,7 +215,7 @@ must_encoding(VALUE enc)
 {
     int index = enc_check_encoding(enc);
     if (index < 0) {
-	not_encoding(enc);
+        not_encoding(enc);
     }
     return DATA_PTR(enc);
 }
@@ -249,16 +225,16 @@ must_encindex(int index)
 {
     rb_encoding *enc = rb_enc_from_index(index);
     if (!enc) {
-	rb_raise(rb_eEncodingError, "encoding index out of bound: %d",
-		 index);
+        rb_raise(rb_eEncodingError, "encoding index out of bound: %d",
+                 index);
     }
     if (ENC_TO_ENCINDEX(enc) != (int)(index & ENC_INDEX_MASK)) {
-	rb_raise(rb_eEncodingError, "wrong encoding index %d for %s (expected %d)",
-		 index, rb_enc_name(enc), ENC_TO_ENCINDEX(enc));
+        rb_raise(rb_eEncodingError, "wrong encoding index %d for %s (expected %d)",
+                 index, rb_enc_name(enc), ENC_TO_ENCINDEX(enc));
     }
     if (rb_enc_autoload_p(enc) && rb_enc_autoload(enc) == -1) {
-	rb_loaderror("failed to load encoding (%s)",
-		     rb_enc_name(enc));
+        rb_loaderror("failed to load encoding (%s)",
+                     rb_enc_name(enc));
     }
     return enc;
 }
@@ -271,16 +247,16 @@ rb_to_encoding_index(VALUE enc)
 
     idx = enc_check_encoding(enc);
     if (idx >= 0) {
-	return idx;
+        return idx;
     }
     else if (NIL_P(enc = rb_check_string_type(enc))) {
-	return -1;
+        return -1;
     }
     if (!rb_enc_asciicompat(rb_enc_get(enc))) {
-	return -1;
+        return -1;
     }
     if (!(name = rb_str_to_cstr(enc))) {
-	return -1;
+        return -1;
     }
     return rb_enc_find_index(name);
 }
@@ -292,10 +268,10 @@ name_for_encoding(volatile VALUE *enc)
     const char *n;
 
     if (!rb_enc_asciicompat(rb_enc_get(name))) {
-	rb_raise(rb_eArgError, "invalid encoding name (non ASCII)");
+        rb_raise(rb_eArgError, "invalid encoding name (non ASCII)");
     }
     if (!(n = rb_str_to_cstr(name))) {
-	rb_raise(rb_eArgError, "invalid encoding name (NUL byte)");
+        rb_raise(rb_eArgError, "invalid encoding name (NUL byte)");
     }
     return n;
 }
@@ -314,7 +290,7 @@ str_to_encindex(VALUE enc)
 {
     int idx = str_find_encindex(enc);
     if (idx < 0) {
-	rb_raise(rb_eArgError, "unknown encoding name - %"PRIsVALUE, enc);
+        rb_raise(rb_eArgError, "unknown encoding name - %"PRIsVALUE, enc);
     }
     return idx;
 }
@@ -345,16 +321,10 @@ rb_find_encoding(VALUE enc)
 static int
 enc_table_expand(struct enc_table *enc_table, int newsize)
 {
-    struct rb_encoding_entry *ent;
-    int count = newsize;
-
-    if (enc_table->size >= newsize) return newsize;
-    newsize = (newsize + 7) / 8 * 8;
-    ent = REALLOC_N(enc_table->list, struct rb_encoding_entry, newsize);
-    memset(ent + enc_table->size, 0, sizeof(*ent)*(newsize - enc_table->size));
-    enc_table->list = ent;
-    enc_table->size = newsize;
-    return count;
+    if (newsize > ENCODING_LIST_CAPA) {
+        rb_raise(rb_eEncodingError, "too many encoding (> %d)", ENCODING_LIST_CAPA);
+    }
+    return newsize;
 }
 
 static int
@@ -365,20 +335,20 @@ enc_register_at(struct enc_table *enc_table, int index, const char *name, rb_enc
 
     if (!valid_encoding_name_p(name)) return -1;
     if (!ent->name) {
-	ent->name = name = strdup(name);
+        ent->name = name = strdup(name);
     }
     else if (STRCASECMP(name, ent->name)) {
-	return -1;
+        return -1;
     }
     encoding = (rb_raw_encoding *)ent->enc;
     if (!encoding) {
-	encoding = xmalloc(sizeof(rb_encoding));
+        encoding = xmalloc(sizeof(rb_encoding));
     }
     if (base_encoding) {
-	*encoding = *base_encoding;
+        *encoding = *base_encoding;
     }
     else {
-	memset(encoding, 0, sizeof(*ent->enc));
+        memset(encoding, 0, sizeof(*ent->enc));
     }
     encoding->name = name;
     encoding->ruby_encoding_index = index;
@@ -405,7 +375,7 @@ static rb_encoding *
 enc_from_index(struct enc_table *enc_table, int index)
 {
     if (UNLIKELY(index < 0 || enc_table->count <= (index &= ENC_INDEX_MASK))) {
-	return 0;
+        return 0;
     }
     return enc_table->list[index].enc;
 }
@@ -413,17 +383,7 @@ enc_from_index(struct enc_table *enc_table, int index)
 rb_encoding *
 rb_enc_from_index(int index)
 {
-    rb_encoding *enc;
-
-    switch (index) {
-      case ENCINDEX_ASCII:    return global_enc_ascii;
-      case ENCINDEX_UTF_8:    return global_enc_utf_8;
-      case ENCINDEX_US_ASCII: return global_enc_us_ascii;
-      default:
-        GLOBAL_ENC_TABLE_EVAL(enc_table,
-                              enc = enc_from_index(enc_table, index));
-        return enc;
-    }
+    return enc_from_index(&global_enc_table, index);
 }
 
 int
@@ -462,9 +422,9 @@ enc_registered(struct enc_table *enc_table, const char *name)
     st_data_t idx = 0;
 
     if (!name) return -1;
-    if (!enc_table->list) return -1;
+    if (!enc_table->names) return -1;
     if (st_lookup(enc_table->names, (st_data_t)name, &idx)) {
-	return (int)idx;
+        return (int)idx;
     }
     return -1;
 }
@@ -484,10 +444,13 @@ rb_encdb_declare(const char *name)
 }
 
 static void
-enc_check_duplication(struct enc_table *enc_table, const char *name)
+enc_check_addable(struct enc_table *enc_table, const char *name)
 {
     if (enc_registered(enc_table, name) >= 0) {
-	rb_raise(rb_eArgError, "encoding %s is already registered", name);
+        rb_raise(rb_eArgError, "encoding %s is already registered", name);
+    }
+    else if (!valid_encoding_name_p(name)) {
+        rb_raise(rb_eArgError, "invalid encoding name: %s", name);
     }
 }
 
@@ -524,11 +487,7 @@ rb_enc_set_base(const char *name, const char *orig)
 int
 rb_enc_set_dummy(int index)
 {
-    rb_encoding *enc;
-
-    GLOBAL_ENC_TABLE_EVAL(enc_table,
-                          enc = enc_table->list[index].enc);
-
+    rb_encoding *enc = global_enc_table.list[index].enc;
     ENC_SET_DUMMY((rb_raw_encoding *)enc);
     return index;
 }
@@ -538,7 +497,7 @@ enc_replicate(struct enc_table *enc_table, const char *name, rb_encoding *encodi
 {
     int idx;
 
-    enc_check_duplication(enc_table, name);
+    enc_check_addable(enc_table, name);
     idx = enc_register(enc_table, name, encoding);
     if (idx < 0) rb_raise(rb_eArgError, "invalid encoding name: %s", name);
     set_base_encoding(enc_table, idx, encoding);
@@ -569,7 +528,10 @@ rb_enc_replicate(const char *name, rb_encoding *encoding)
 static VALUE
 enc_replicate_m(VALUE encoding, VALUE name)
 {
-    int idx = rb_enc_replicate(name_for_encoding(&name), rb_to_encoding(encoding));
+    int idx;
+    rb_warn_deprecated_to_remove("3.3", "Encoding#replicate", "the original encoding");
+
+    idx = rb_enc_replicate(name_for_encoding(&name), rb_to_encoding(encoding));
     RB_GC_GUARD(name);
     return rb_enc_from_encoding_index(idx);
 }
@@ -581,11 +543,11 @@ enc_replicate_with_index(struct enc_table *enc_table, const char *name, rb_encod
         idx = enc_register(enc_table, name, origenc);
     }
     else {
-	idx = enc_register_at(enc_table, idx, name, origenc);
+        idx = enc_register_at(enc_table, idx, name, origenc);
     }
     if (idx >= 0) {
-	set_base_encoding(enc_table, idx, origenc);
-	set_encoding_const(name, rb_enc_from_index(idx));
+        set_base_encoding(enc_table, idx, origenc);
+        set_encoding_const(name, rb_enc_from_index(idx));
     }
     else {
         rb_raise(rb_eArgError, "failed to replicate encoding");
@@ -705,7 +667,7 @@ static int
 enc_alias_internal(struct enc_table *enc_table, const char *alias, int idx)
 {
     return st_insert2(enc_table->names, (st_data_t)alias, (st_data_t)idx,
-		      enc_dup_name);
+                      enc_dup_name);
 }
 
 static int
@@ -713,7 +675,7 @@ enc_alias(struct enc_table *enc_table, const char *alias, int idx)
 {
     if (!valid_encoding_name_p(alias)) return -1;
     if (!enc_alias_internal(enc_table, alias, idx))
-	set_encoding_const(alias, enc_from_index(enc_table, idx));
+        set_encoding_const(alias, enc_from_index(enc_table, idx));
     return idx;
 }
 
@@ -724,7 +686,7 @@ rb_enc_alias(const char *alias, const char *orig)
 
     GLOBAL_ENC_TABLE_ENTER(enc_table);
     {
-        enc_check_duplication(enc_table, alias);
+        enc_check_addable(enc_table, alias);
         if ((idx = rb_enc_find_index(orig)) < 0) {
             r =  -1;
         }
@@ -756,29 +718,23 @@ rb_encdb_alias(const char *alias, const char *orig)
     return r;
 }
 
-void
-rb_encdb_set_unicode(int index)
-{
-    rb_raw_encoding *enc = (rb_raw_encoding *)rb_enc_from_index(index);
-    ASSUME(enc);
-    enc->flags |= ONIGENC_FLAG_UNICODE;
-}
-
 static void
 rb_enc_init(struct enc_table *enc_table)
 {
     enc_table_expand(enc_table, ENCODING_COUNT + 1);
     if (!enc_table->names) {
-	enc_table->names = st_init_strcasetable();
+        enc_table->names = st_init_strcasetable_with_size(ENCODING_LIST_CAPA);
     }
+#define OnigEncodingASCII_8BIT OnigEncodingASCII
 #define ENC_REGISTER(enc) enc_register_at(enc_table, ENCINDEX_##enc, rb_enc_name(&OnigEncoding##enc), &OnigEncoding##enc)
-    ENC_REGISTER(ASCII);
+    ENC_REGISTER(ASCII_8BIT);
     ENC_REGISTER(UTF_8);
     ENC_REGISTER(US_ASCII);
-    global_enc_ascii = enc_table->list[ENCINDEX_ASCII].enc;
+    global_enc_ascii = enc_table->list[ENCINDEX_ASCII_8BIT].enc;
     global_enc_utf_8 = enc_table->list[ENCINDEX_UTF_8].enc;
     global_enc_us_ascii = enc_table->list[ENCINDEX_US_ASCII].enc;
 #undef ENC_REGISTER
+#undef OnigEncodingASCII_8BIT
 #define ENCDB_REGISTER(name, enc) enc_register_at(enc_table, ENCINDEX_##enc, name, NULL)
     ENCDB_REGISTER("UTF-16BE", UTF_16BE);
     ENCDB_REGISTER("UTF-16LE", UTF_16LE);
@@ -813,9 +769,9 @@ load_encoding(const char *name)
     int idx;
 
     while (s < e) {
-	if (!ISALNUM(*s)) *s = '_';
-	else if (ISUPPER(*s)) *s = (char)TOLOWER(*s);
-	++s;
+        if (!ISALNUM(*s)) *s = '_';
+        else if (ISUPPER(*s)) *s = (char)TOLOWER(*s);
+        ++s;
     }
     enclib = rb_fstring(enclib);
     ruby_debug = Qfalse;
@@ -848,16 +804,16 @@ enc_autoload_body(struct enc_table *enc_table, rb_encoding *enc)
 
     if (base) {
         int i = 0;
-	do {
-	    if (i >= enc_table->count) return -1;
-	} while (enc_table->list[i].enc != base && (++i, 1));
-	if (rb_enc_autoload_p(base)) {
-	    if (rb_enc_autoload(base) < 0) return -1;
-	}
-	i = enc->ruby_encoding_index;
-	enc_register_at(enc_table, i & ENC_INDEX_MASK, rb_enc_name(enc), base);
+        do {
+            if (i >= enc_table->count) return -1;
+        } while (enc_table->list[i].enc != base && (++i, 1));
+        if (rb_enc_autoload_p(base)) {
+            if (rb_enc_autoload(base) < 0) return -1;
+        }
+        i = enc->ruby_encoding_index;
+        enc_register_at(enc_table, i & ENC_INDEX_MASK, rb_enc_name(enc), base);
         ((rb_raw_encoding *)enc)->ruby_encoding_index = i;
-	i &= ENC_INDEX_MASK;
+        i &= ENC_INDEX_MASK;
         return i;
     }
     else {
@@ -880,25 +836,23 @@ rb_enc_autoload(rb_encoding *enc)
 int
 rb_enc_find_index(const char *name)
 {
-    int i;
+    int i = enc_registered(&global_enc_table, name);
     rb_encoding *enc;
 
-    GLOBAL_ENC_TABLE_EVAL(enc_table, i = enc_registered(enc_table, name));
-
     if (i < 0) {
-	i = load_encoding(name);
+        i = load_encoding(name);
     }
     else if (!(enc = rb_enc_from_index(i))) {
-	if (i != UNSPECIFIED_ENCODING) {
-	    rb_raise(rb_eArgError, "encoding %s is not registered", name);
-	}
+        if (i != UNSPECIFIED_ENCODING) {
+            rb_raise(rb_eArgError, "encoding %s is not registered", name);
+        }
     }
     else if (rb_enc_autoload_p(enc)) {
-	if (rb_enc_autoload(enc) < 0) {
-	    rb_warn("failed to load encoding (%s); use ASCII-8BIT instead",
-		    name);
-	    return 0;
-	}
+        if (rb_enc_autoload(enc) < 0) {
+            rb_warn("failed to load encoding (%s); use ASCII-8BIT instead",
+                    name);
+            return 0;
+        }
     }
     return i;
 }
@@ -931,11 +885,11 @@ enc_capable(VALUE obj)
       case T_REGEXP:
       case T_FILE:
       case T_SYMBOL:
-	return TRUE;
+        return TRUE;
       case T_DATA:
-	if (is_data_encoding(obj)) return TRUE;
+        if (is_data_encoding(obj)) return TRUE;
       default:
-	return FALSE;
+        return FALSE;
     }
 }
 
@@ -957,11 +911,11 @@ enc_get_index_str(VALUE str)
 {
     int i = ENCODING_GET_INLINED(str);
     if (i == ENCODING_INLINE_MAX) {
-	VALUE iv;
+        VALUE iv;
 
 #if 0
-	iv = rb_ivar_get(str, rb_id_encoding());
-	i = NUM2INT(iv);
+        iv = rb_ivar_get(str, rb_id_encoding());
+        i = NUM2INT(iv);
 #else
         /*
          * Tentatively, assume ASCII-8BIT, if encoding index instance
@@ -969,7 +923,7 @@ enc_get_index_str(VALUE str)
          * all instance variables are removed in `obj_free`.
          */
         iv = rb_attr_get(str, rb_id_encoding());
-        i = NIL_P(iv) ? ENCINDEX_ASCII : NUM2INT(iv);
+        i = NIL_P(iv) ? ENCINDEX_ASCII_8BIT : NUM2INT(iv);
 #endif
     }
     return i;
@@ -982,31 +936,31 @@ rb_enc_get_index(VALUE obj)
     VALUE tmp;
 
     if (SPECIAL_CONST_P(obj)) {
-	if (!SYMBOL_P(obj)) return -1;
-	obj = rb_sym2str(obj);
+        if (!SYMBOL_P(obj)) return -1;
+        obj = rb_sym2str(obj);
     }
     switch (BUILTIN_TYPE(obj)) {
       case T_STRING:
       case T_SYMBOL:
       case T_REGEXP:
-	i = enc_get_index_str(obj);
-	break;
+        i = enc_get_index_str(obj);
+        break;
       case T_FILE:
-	tmp = rb_funcallv(obj, rb_intern("internal_encoding"), 0, 0);
-	if (NIL_P(tmp)) {
-	    tmp = rb_funcallv(obj, rb_intern("external_encoding"), 0, 0);
-	}
-	if (is_obj_encoding(tmp)) {
-	    i = enc_check_encoding(tmp);
-	}
-	break;
+        tmp = rb_funcallv(obj, rb_intern("internal_encoding"), 0, 0);
+        if (NIL_P(tmp)) {
+            tmp = rb_funcallv(obj, rb_intern("external_encoding"), 0, 0);
+        }
+        if (is_obj_encoding(tmp)) {
+            i = enc_check_encoding(tmp);
+        }
+        break;
       case T_DATA:
-	if (is_data_encoding(obj)) {
-	    i = enc_check_encoding(obj);
-	}
-	break;
+        if (is_data_encoding(obj)) {
+            i = enc_check_encoding(obj);
+        }
+        break;
       default:
-	break;
+        break;
     }
     return i;
 }
@@ -1019,8 +973,8 @@ enc_set_index(VALUE obj, int idx)
     }
 
     if (idx < ENCODING_INLINE_MAX) {
-	ENCODING_SET_INLINED(obj, idx);
-	return;
+        ENCODING_SET_INLINED(obj, idx);
+        return;
     }
     ENCODING_SET_INLINED(obj, ENCODING_INLINE_MAX);
     rb_ivar_set(obj, rb_id_encoding(), INT2NUM(idx));
@@ -1044,19 +998,19 @@ rb_enc_associate_index(VALUE obj, int idx)
     rb_check_frozen(obj);
     oldidx = rb_enc_get_index(obj);
     if (oldidx == idx)
-	return obj;
+        return obj;
     if (SPECIAL_CONST_P(obj)) {
-	rb_raise(rb_eArgError, "cannot set encoding");
+        rb_raise(rb_eArgError, "cannot set encoding");
     }
     enc = must_encindex(idx);
     if (!ENC_CODERANGE_ASCIIONLY(obj) ||
-	!rb_enc_asciicompat(enc)) {
-	ENC_CODERANGE_CLEAR(obj);
+        !rb_enc_asciicompat(enc)) {
+        ENC_CODERANGE_CLEAR(obj);
     }
     termlen = rb_enc_mbminlen(enc);
     oldtermlen = rb_enc_mbminlen(rb_enc_from_index(oldidx));
     if (oldtermlen != termlen && RB_TYPE_P(obj, T_STRING)) {
-	rb_str_change_terminator_length(obj, oldtermlen, termlen);
+        rb_str_change_terminator_length(obj, oldtermlen, termlen);
     }
     enc_set_index(obj, idx);
     return obj;
@@ -1078,9 +1032,9 @@ static rb_encoding*
 rb_encoding_check(rb_encoding* enc, VALUE str1, VALUE str2)
 {
     if (!enc)
-	rb_raise(rb_eEncCompatError, "incompatible character encodings: %s and %s",
-		 rb_enc_name(rb_enc_get(str1)),
-		 rb_enc_name(rb_enc_get(str2)));
+        rb_raise(rb_eEncCompatError, "incompatible character encodings: %s and %s",
+                 rb_enc_name(rb_enc_get(str1)),
+                 rb_enc_name(rb_enc_get(str2)));
     return enc;
 }
 
@@ -1109,48 +1063,48 @@ enc_compatible_latter(VALUE str1, VALUE str2, int idx1, int idx2)
 
     isstr2 = RB_TYPE_P(str2, T_STRING);
     if (isstr2 && RSTRING_LEN(str2) == 0)
-	return enc1;
+        return enc1;
     isstr1 = RB_TYPE_P(str1, T_STRING);
     if (isstr1 && isstr2 && RSTRING_LEN(str1) == 0)
-	return (rb_enc_asciicompat(enc1) && rb_enc_str_asciionly_p(str2)) ? enc1 : enc2;
+        return (rb_enc_asciicompat(enc1) && rb_enc_str_asciionly_p(str2)) ? enc1 : enc2;
     if (!rb_enc_asciicompat(enc1) || !rb_enc_asciicompat(enc2)) {
-	return 0;
+        return 0;
     }
 
     /* objects whose encoding is the same of contents */
     if (!isstr2 && idx2 == ENCINDEX_US_ASCII)
-	return enc1;
+        return enc1;
     if (!isstr1 && idx1 == ENCINDEX_US_ASCII)
-	return enc2;
+        return enc2;
 
     if (!isstr1) {
-	VALUE tmp = str1;
-	int idx0 = idx1;
-	str1 = str2;
-	str2 = tmp;
-	idx1 = idx2;
-	idx2 = idx0;
-	idx0 = isstr1;
-	isstr1 = isstr2;
-	isstr2 = idx0;
+        VALUE tmp = str1;
+        int idx0 = idx1;
+        str1 = str2;
+        str2 = tmp;
+        idx1 = idx2;
+        idx2 = idx0;
+        idx0 = isstr1;
+        isstr1 = isstr2;
+        isstr2 = idx0;
     }
     if (isstr1) {
-	int cr1, cr2;
-
-	cr1 = rb_enc_str_coderange(str1);
-	if (isstr2) {
-	    cr2 = rb_enc_str_coderange(str2);
-	    if (cr1 != cr2) {
-		/* may need to handle ENC_CODERANGE_BROKEN */
-		if (cr1 == ENC_CODERANGE_7BIT) return enc2;
-		if (cr2 == ENC_CODERANGE_7BIT) return enc1;
-	    }
-	    if (cr2 == ENC_CODERANGE_7BIT) {
-		return enc1;
-	    }
-	}
-	if (cr1 == ENC_CODERANGE_7BIT)
-	    return enc2;
+        int cr1, cr2;
+
+        cr1 = rb_enc_str_coderange(str1);
+        if (isstr2) {
+            cr2 = rb_enc_str_coderange(str2);
+            if (cr1 != cr2) {
+                /* may need to handle ENC_CODERANGE_BROKEN */
+                if (cr1 == ENC_CODERANGE_7BIT) return enc2;
+                if (cr2 == ENC_CODERANGE_7BIT) return enc1;
+            }
+            if (cr2 == ENC_CODERANGE_7BIT) {
+                return enc1;
+            }
+        }
+        if (cr1 == ENC_CODERANGE_7BIT)
+            return enc2;
     }
     return 0;
 }
@@ -1165,10 +1119,10 @@ enc_compatible_str(VALUE str1, VALUE str2)
         return 0;
 
     if (idx1 == idx2) {
-	return rb_enc_from_index(idx1);
+        return rb_enc_from_index(idx1);
     }
     else {
-	return enc_compatible_latter(str1, str2, idx1, idx2);
+        return enc_compatible_latter(str1, str2, idx1, idx2);
     }
 }
 
@@ -1182,7 +1136,7 @@ rb_enc_compatible(VALUE str1, VALUE str2)
         return 0;
 
     if (idx1 == idx2) {
-	return rb_enc_from_index(idx1);
+        return rb_enc_from_index(idx1);
     }
 
     return enc_compatible_latter(str1, str2, idx1, idx2);
@@ -1207,7 +1161,7 @@ rb_obj_encoding(VALUE obj)
 {
     int idx = rb_enc_get_index(obj);
     if (idx < 0) {
-	rb_raise(rb_eTypeError, "unknown encoding");
+        rb_raise(rb_eTypeError, "unknown encoding");
     }
     return rb_enc_from_encoding_index(idx & ENC_INDEX_MASK);
 }
@@ -1274,7 +1228,7 @@ rb_enc_codepoint_len(const char *p, const char *e, int *len_p, rb_encoding *enc)
         rb_raise(rb_eArgError, "empty string");
     r = rb_enc_precise_mbclen(p, e, enc);
     if (!MBCLEN_CHARFOUND_P(r)) {
-	rb_raise(rb_eArgError, "invalid byte sequence in %s", rb_enc_name(enc));
+        rb_raise(rb_eArgError, "invalid byte sequence in %s", rb_enc_name(enc));
     }
     if (len_p) *len_p = MBCLEN_CHARFOUND_LEN(r);
     return rb_enc_mbc_to_codepoint(p, e, enc);
@@ -1285,7 +1239,7 @@ rb_enc_codelen(int c, rb_encoding *enc)
 {
     int n = ONIGENC_CODE_TO_MBCLEN(enc,c);
     if (n == 0) {
-	rb_raise(rb_eArgError, "invalid codepoint 0x%x in %s", c, rb_enc_name(enc));
+        rb_raise(rb_eArgError, "invalid codepoint 0x%x in %s", c, rb_enc_name(enc));
     }
     return n;
 }
@@ -1317,16 +1271,16 @@ enc_inspect(VALUE self)
     rb_encoding *enc;
 
     if (!is_data_encoding(self)) {
-	not_encoding(self);
+        not_encoding(self);
     }
     if (!(enc = DATA_PTR(self)) || rb_enc_from_index(rb_enc_to_index(enc)) != enc) {
-	rb_raise(rb_eTypeError, "broken Encoding");
+        rb_raise(rb_eTypeError, "broken Encoding");
     }
     return rb_enc_sprintf(rb_usascii_encoding(),
-			  "#<%"PRIsVALUE":%s%s%s>", rb_obj_class(self),
-			  rb_enc_name(enc),
-			  (ENC_DUMMY_P(enc) ? " (dummy)" : ""),
-			  rb_enc_autoload_p(enc) ? " (autoload)" : "");
+                          "#<%"PRIsVALUE":%s%s%s>", rb_obj_class(self),
+                          rb_enc_name(enc),
+                          (ENC_DUMMY_P(enc) ? " (dummy)" : ""),
+                          rb_enc_autoload_p(enc) ? " (autoload)" : "");
 }
 
 /*
@@ -1350,8 +1304,8 @@ enc_names_i(st_data_t name, st_data_t idx, st_data_t args)
     VALUE *arg = (VALUE *)args;
 
     if ((int)idx == (int)arg[0]) {
-	VALUE str = rb_fstring_cstr((char *)name);
-	rb_ary_push(arg[1], str);
+        VALUE str = rb_fstring_cstr((char *)name);
+        rb_ary_push(arg[1], str);
     }
     return ST_CONTINUE;
 }
@@ -1371,10 +1325,7 @@ enc_names(VALUE self)
 
     args[0] = (VALUE)rb_to_encoding_index(self);
     args[1] = rb_ary_new2(0);
-
-    GLOBAL_ENC_TABLE_EVAL(enc_table,
-                          st_foreach(enc_table->names, enc_names_i, (st_data_t)args));
-
+    st_foreach(global_enc_table.names, enc_names_i, (st_data_t)args);
     return args[1];
 }
 
@@ -1400,14 +1351,7 @@ static VALUE
 enc_list(VALUE klass)
 {
     VALUE ary = rb_ary_new2(0);
-
-    RB_VM_LOCK_ENTER();
-    {
-        rb_ary_replace(ary, rb_default_encoding_list);
-        rb_ary_concat(ary, rb_additional_encoding_list);
-    }
-    RB_VM_LOCK_LEAVE();
-
+    rb_ary_replace(ary, rb_encoding_list);
     return ary;
 }
 
@@ -1438,7 +1382,7 @@ enc_find(VALUE klass, VALUE enc)
 {
     int idx;
     if (is_obj_encoding(enc))
-	return enc;
+        return enc;
     idx = str_to_encindex(enc);
     if (idx == UNSPECIFIED_ENCODING) return Qnil;
     return rb_enc_from_encoding_index(idx);
@@ -1520,7 +1464,7 @@ rb_ascii8bit_encoding(void)
 int
 rb_ascii8bit_encindex(void)
 {
-    return ENCINDEX_ASCII;
+    return ENCINDEX_ASCII_8BIT;
 }
 
 rb_encoding *
@@ -1556,15 +1500,17 @@ rb_locale_encindex(void)
 
     if (idx < 0) idx = ENCINDEX_UTF_8;
 
-    GLOBAL_ENC_TABLE_ENTER(enc_table);
-    if (enc_registered(enc_table, "locale") < 0) {
+    if (enc_registered(&global_enc_table, "locale") < 0) {
 # if defined _WIN32
-	void Init_w32_codepage(void);
-	Init_w32_codepage();
+        void Init_w32_codepage(void);
+        Init_w32_codepage();
 # endif
-	enc_alias_internal(enc_table, "locale", idx);
+        GLOBAL_ENC_TABLE_ENTER(enc_table);
+        {
+            enc_alias_internal(enc_table, "locale", idx);
+        }
+        GLOBAL_ENC_TABLE_LEAVE();
     }
-    GLOBAL_ENC_TABLE_LEAVE();
 
     return idx;
 }
@@ -1578,13 +1524,8 @@ rb_locale_encoding(void)
 int
 rb_filesystem_encindex(void)
 {
-    int idx;
-
-    GLOBAL_ENC_TABLE_EVAL(enc_table,
-                          idx = enc_registered(enc_table, "filesystem"));
-
-    if (idx < 0)
-	idx = ENCINDEX_ASCII;
+    int idx = enc_registered(&global_enc_table, "filesystem");
+    if (idx < 0) idx = ENCINDEX_ASCII_8BIT;
     return idx;
 }
 
@@ -1607,15 +1548,22 @@ enc_set_default_encoding(struct default_encoding *def, VALUE encoding, const cha
     int overridden = FALSE;
 
     if (def->index != -2)
-	/* Already set */
-	overridden = TRUE;
+        /* Already set */
+        overridden = TRUE;
 
     GLOBAL_ENC_TABLE_ENTER(enc_table);
     {
         if (NIL_P(encoding)) {
             def->index = -1;
             def->enc = 0;
-            st_insert(enc_table->names, (st_data_t)strdup(name),
+            char *name_dup = strdup(name);
+
+            st_data_t existing_name = (st_data_t)name_dup;
+            if (st_delete(enc_table->names, &existing_name, NULL)) {
+                xfree((void *)existing_name);
+            }
+
+            st_insert(enc_table->names, (st_data_t)name_dup,
                       (st_data_t)UNSPECIFIED_ENCODING);
         }
         else {
@@ -1807,45 +1755,45 @@ set_encoding_const(const char *name, rb_encoding *enc)
 
     if (ISDIGIT(*s)) return;
     if (ISUPPER(*s)) {
-	hasupper = 1;
-	while (*++s && (ISALNUM(*s) || *s == '_')) {
-	    if (ISLOWER(*s)) haslower = 1;
-	}
+        hasupper = 1;
+        while (*++s && (ISALNUM(*s) || *s == '_')) {
+            if (ISLOWER(*s)) haslower = 1;
+        }
     }
     if (!*s) {
-	if (s - name > ENCODING_NAMELEN_MAX) return;
-	valid = 1;
-	rb_define_const(rb_cEncoding, name, encoding);
+        if (s - name > ENCODING_NAMELEN_MAX) return;
+        valid = 1;
+        rb_define_const(rb_cEncoding, name, encoding);
     }
     if (!valid || haslower) {
-	size_t len = s - name;
-	if (len > ENCODING_NAMELEN_MAX) return;
-	if (!haslower || !hasupper) {
-	    do {
-		if (ISLOWER(*s)) haslower = 1;
-		if (ISUPPER(*s)) hasupper = 1;
-	    } while (*++s && (!haslower || !hasupper));
-	    len = s - name;
-	}
-	len += strlen(s);
-	if (len++ > ENCODING_NAMELEN_MAX) return;
-	MEMCPY(s = ALLOCA_N(char, len), name, char, len);
-	name = s;
-	if (!valid) {
-	    if (ISLOWER(*s)) *s = ONIGENC_ASCII_CODE_TO_UPPER_CASE((int)*s);
-	    for (; *s; ++s) {
-		if (!ISALNUM(*s)) *s = '_';
-	    }
-	    if (hasupper) {
-		rb_define_const(rb_cEncoding, name, encoding);
-	    }
-	}
-	if (haslower) {
-	    for (s = (char *)name; *s; ++s) {
-		if (ISLOWER(*s)) *s = ONIGENC_ASCII_CODE_TO_UPPER_CASE((int)*s);
-	    }
-	    rb_define_const(rb_cEncoding, name, encoding);
-	}
+        size_t len = s - name;
+        if (len > ENCODING_NAMELEN_MAX) return;
+        if (!haslower || !hasupper) {
+            do {
+                if (ISLOWER(*s)) haslower = 1;
+                if (ISUPPER(*s)) hasupper = 1;
+            } while (*++s && (!haslower || !hasupper));
+            len = s - name;
+        }
+        len += strlen(s);
+        if (len++ > ENCODING_NAMELEN_MAX) return;
+        MEMCPY(s = ALLOCA_N(char, len), name, char, len);
+        name = s;
+        if (!valid) {
+            if (ISLOWER(*s)) *s = ONIGENC_ASCII_CODE_TO_UPPER_CASE((int)*s);
+            for (; *s; ++s) {
+                if (!ISALNUM(*s)) *s = '_';
+            }
+            if (hasupper) {
+                rb_define_const(rb_cEncoding, name, encoding);
+            }
+        }
+        if (haslower) {
+            for (s = (char *)name; *s; ++s) {
+                if (ISLOWER(*s)) *s = ONIGENC_ASCII_CODE_TO_UPPER_CASE((int)*s);
+            }
+            rb_define_const(rb_cEncoding, name, encoding);
+        }
     }
 }
 
@@ -1875,15 +1823,8 @@ rb_enc_name_list_i(st_data_t name, st_data_t idx, st_data_t arg)
 static VALUE
 rb_enc_name_list(VALUE klass)
 {
-    VALUE ary;
-
-    GLOBAL_ENC_TABLE_ENTER(enc_table);
-    {
-        ary = rb_ary_new2(enc_table->names->num_entries);
-        st_foreach(enc_table->names, rb_enc_name_list_i, (st_data_t)ary);
-    }
-    GLOBAL_ENC_TABLE_LEAVE();
-
+    VALUE ary = rb_ary_new2(global_enc_table.names->num_entries);
+    st_foreach(global_enc_table.names, rb_enc_name_list_i, (st_data_t)ary);
     return ary;
 }
 
@@ -1896,14 +1837,14 @@ rb_enc_aliases_enc_i(st_data_t name, st_data_t orig, st_data_t arg)
     VALUE key, str = rb_ary_entry(ary, idx);
 
     if (NIL_P(str)) {
-	rb_encoding *enc = rb_enc_from_index(idx);
+        rb_encoding *enc = rb_enc_from_index(idx);
 
-	if (!enc) return ST_CONTINUE;
-	if (STRCASECMP((char*)name, rb_enc_name(enc)) == 0) {
-	    return ST_CONTINUE;
-	}
-	str = rb_fstring_cstr(rb_enc_name(enc));
-	rb_ary_store(ary, idx, str);
+        if (!enc) return ST_CONTINUE;
+        if (STRCASECMP((char*)name, rb_enc_name(enc)) == 0) {
+            return ST_CONTINUE;
+        }
+        str = rb_fstring_cstr(rb_enc_name(enc));
+        rb_ary_store(ary, idx, str);
     }
     key = rb_fstring_cstr((char *)name);
     rb_hash_aset(aliases, key, str);
@@ -1929,8 +1870,7 @@ rb_enc_aliases(VALUE klass)
     aliases[0] = rb_hash_new();
     aliases[1] = rb_ary_new();
 
-    GLOBAL_ENC_TABLE_EVAL(enc_table,
-                          st_foreach(enc_table->names, rb_enc_aliases_enc_i, (st_data_t)aliases));
+    st_foreach(global_enc_table.names, rb_enc_aliases_enc_i, (st_data_t)aliases);
 
     return aliases[0];
 }
@@ -1999,18 +1939,12 @@ Init_Encoding(void)
 
     struct enc_table *enc_table = &global_enc_table;
 
-    if (DEFAULT_ENCODING_LIST_CAPA < enc_table->count) rb_bug("DEFAULT_ENCODING_LIST_CAPA is too small");
-
-    list = rb_additional_encoding_list = rb_ary_new();
-    RBASIC_CLEAR_CLASS(list);
-    rb_gc_register_mark_object(list);
-
-    list = rb_default_encoding_list = rb_ary_new2(DEFAULT_ENCODING_LIST_CAPA);
+    list = rb_encoding_list = rb_ary_new2(ENCODING_LIST_CAPA);
     RBASIC_CLEAR_CLASS(list);
     rb_gc_register_mark_object(list);
 
     for (i = 0; i < enc_table->count; ++i) {
-	rb_ary_push(list, enc_new(enc_table->list[i].enc));
+        rb_ary_push(list, enc_new(enc_table->list[i].enc));
     }
 
     rb_marshal_define_compat(rb_cEncoding, Qnil, 0, enc_m_loader);
@@ -2027,5 +1961,5 @@ Init_encodings(void)
 void
 rb_enc_foreach_name(int (*func)(st_data_t name, st_data_t idx, st_data_t arg), st_data_t arg)
 {
-    GLOBAL_ENC_TABLE_EVAL(enc_table, st_foreach(enc_table->names, func, arg));
+    st_foreach(global_enc_table.names, func, arg);
 }
diff --git a/enum.c b/enum.c
index bb12f18e0f..b3c715e0a1 100644
--- a/enum.c
+++ b/enum.c
@@ -65,9 +65,9 @@ static VALUE
 enum_yield(int argc, VALUE ary)
 {
     if (argc > 1)
-	return rb_yield_force_blockarg(ary);
+        return rb_yield_force_blockarg(ary);
     if (argc == 1)
-	return rb_yield(ary);
+        return rb_yield(ary);
     return rb_yield_values2(0, 0);
 }
 
@@ -77,9 +77,9 @@ enum_yield_array(VALUE ary)
     long len = RARRAY_LEN(ary);
 
     if (len > 1)
-	return rb_yield_force_blockarg(ary);
+        return rb_yield_force_blockarg(ary);
     if (len == 1)
-	return rb_yield(RARRAY_AREF(ary, 0));
+        return rb_yield(RARRAY_AREF(ary, 0));
     return rb_yield_values2(0, 0);
 }
 
@@ -90,7 +90,7 @@ grep_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, args))
     ENUM_WANT_SVALUE();
 
     if (RTEST(rb_funcallv(memo->v1, id_eqq, 1, &i)) == RTEST(memo->u3.value)) {
-	rb_ary_push(memo->v2, i);
+        rb_ary_push(memo->v2, i);
     }
     return Qnil;
 }
@@ -106,7 +106,7 @@ grep_regexp_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, args))
     converted_element = SYMBOL_P(i) ? i : rb_check_string_type(i);
     match = NIL_P(converted_element) ? Qfalse : rb_reg_match_p(memo->v1, i, 0);
     if (match == memo->u3.value) {
-	rb_ary_push(memo->v2, i);
+        rb_ary_push(memo->v2, i);
     }
     return Qnil;
 }
@@ -118,7 +118,7 @@ grep_iter_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, args))
     ENUM_WANT_SVALUE();
 
     if (RTEST(rb_funcallv(memo->v1, id_eqq, 1, &i)) == RTEST(memo->u3.value)) {
-	rb_ary_push(memo->v2, enum_yield(argc, i));
+        rb_ary_push(memo->v2, enum_yield(argc, i));
     }
     return Qnil;
 }
@@ -130,14 +130,14 @@ enum_grep0(VALUE obj, VALUE pat, VALUE test)
     struct MEMO *memo = MEMO_NEW(pat, ary, test);
     rb_block_call_func_t fn;
     if (rb_block_given_p()) {
-	fn = grep_iter_i;
+        fn = grep_iter_i;
     }
     else if (RB_TYPE_P(pat, T_REGEXP) &&
       LIKELY(rb_method_basic_definition_p(CLASS_OF(pat), idEqq))) {
-	fn = grep_regexp_i;
+        fn = grep_regexp_i;
     }
     else {
-	fn = grep_i;
+        fn = grep_i;
     }
     rb_block_call(obj, id_each, 0, 0, fn, (VALUE)memo);
 
@@ -214,13 +214,13 @@ static void
 imemo_count_up(struct MEMO *memo)
 {
     if (memo->flags & COUNT_BIGNUM) {
-	MEMO_V3_SET(memo, rb_int_succ(memo->u3.value));
+        MEMO_V3_SET(memo, rb_int_succ(memo->u3.value));
     }
     else if (++memo->u3.cnt == 0) {
-	/* overflow */
-	unsigned long buf[2] = {0, 1};
-	MEMO_V3_SET(memo, rb_big_unpack(buf, 2));
-	memo->flags |= COUNT_BIGNUM;
+        /* overflow */
+        unsigned long buf[2] = {0, 1};
+        MEMO_V3_SET(memo, rb_big_unpack(buf, 2));
+        memo->flags |= COUNT_BIGNUM;
     }
 }
 
@@ -228,10 +228,10 @@ static VALUE
 imemo_count_value(struct MEMO *memo)
 {
     if (memo->flags & COUNT_BIGNUM) {
-	return memo->u3.value;
+        return memo->u3.value;
     }
     else {
-	return ULONG2NUM(memo->u3.cnt);
+        return ULONG2NUM(memo->u3.cnt);
     }
 }
 
@@ -243,7 +243,7 @@ count_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, memop))
     ENUM_WANT_SVALUE();
 
     if (rb_equal(i, memo->v1)) {
-	imemo_count_up(memo);
+        imemo_count_up(memo);
     }
     return Qnil;
 }
@@ -254,7 +254,7 @@ count_iter_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, memop))
     struct MEMO *memo = MEMO_CAST(memop);
 
     if (RTEST(rb_yield_values2(argc, argv))) {
-	imemo_count_up(memo);
+        imemo_count_up(memo);
     }
     return Qnil;
 }
@@ -302,18 +302,18 @@ enum_count(int argc, VALUE *argv, VALUE obj)
     rb_block_call_func *func;
 
     if (argc == 0) {
-	if (rb_block_given_p()) {
-	    func = count_iter_i;
-	}
-	else {
-	    func = count_all_i;
-	}
+        if (rb_block_given_p()) {
+            func = count_iter_i;
+        }
+        else {
+            func = count_all_i;
+        }
     }
     else {
-	rb_scan_args(argc, argv, "1", &item);
-	if (rb_block_given_p()) {
-	    rb_warn("given block not used");
-	}
+        rb_scan_args(argc, argv, "1", &item);
+        if (rb_block_given_p()) {
+            rb_warn("given block not used");
+        }
         func = count_i;
     }
 
@@ -328,10 +328,10 @@ find_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, memop))
     ENUM_WANT_SVALUE();
 
     if (RTEST(enum_yield(argc, i))) {
-	struct MEMO *memo = MEMO_CAST(memop);
-	MEMO_V1_SET(memo, i);
-	memo->u3.cnt = 1;
-	rb_iter_break();
+        struct MEMO *memo = MEMO_CAST(memop);
+        MEMO_V1_SET(memo, i);
+        memo->u3.cnt = 1;
+        rb_iter_break();
     }
     return Qnil;
 }
@@ -368,10 +368,10 @@ enum_find(int argc, VALUE *argv, VALUE obj)
     memo = MEMO_NEW(Qundef, 0, 0);
     rb_block_call(obj, id_each, 0, 0, find_i, (VALUE)memo);
     if (memo->u3.cnt) {
-	return memo->v1;
+        return memo->v1;
     }
     if (!NIL_P(if_none)) {
-	return rb_funcallv(if_none, id_call, 0, 0);
+        return rb_funcallv(if_none, id_call, 0, 0);
     }
     return Qnil;
 }
@@ -384,8 +384,8 @@ find_index_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, memop))
     ENUM_WANT_SVALUE();
 
     if (rb_equal(i, memo->v2)) {
-	MEMO_V1_SET(memo, imemo_count_value(memo));
-	rb_iter_break();
+        MEMO_V1_SET(memo, imemo_count_value(memo));
+        rb_iter_break();
     }
     imemo_count_up(memo);
     return Qnil;
@@ -397,8 +397,8 @@ find_index_iter_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, memop))
     struct MEMO *memo = MEMO_CAST(memop);
 
     if (RTEST(rb_yield_values2(argc, argv))) {
-	MEMO_V1_SET(memo, imemo_count_value(memo));
-	rb_iter_break();
+        MEMO_V1_SET(memo, imemo_count_value(memo));
+        rb_iter_break();
     }
     imemo_count_up(memo);
     return Qnil;
@@ -440,10 +440,10 @@ enum_find_index(int argc, VALUE *argv, VALUE obj)
         func = find_index_iter_i;
     }
     else {
-	rb_scan_args(argc, argv, "1", &condition_value);
-	if (rb_block_given_p()) {
-	    rb_warn("given block not used");
-	}
+        rb_scan_args(argc, argv, "1", &condition_value);
+        if (rb_block_given_p()) {
+            rb_warn("given block not used");
+        }
         func = find_index_i;
     }
 
@@ -458,7 +458,7 @@ find_all_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, ary))
     ENUM_WANT_SVALUE();
 
     if (RTEST(enum_yield(argc, i))) {
-	rb_ary_push(ary, i);
+        rb_ary_push(ary, i);
     }
     return Qnil;
 }
@@ -566,7 +566,7 @@ reject_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, ary))
     ENUM_WANT_SVALUE();
 
     if (!RTEST(enum_yield(argc, i))) {
-	rb_ary_push(ary, i);
+        rb_ary_push(ary, i);
     }
     return Qnil;
 }
@@ -658,10 +658,10 @@ flat_map_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, ary))
     tmp = rb_check_array_type(i);
 
     if (NIL_P(tmp)) {
-	rb_ary_push(ary, i);
+        rb_ary_push(ary, i);
     }
     else {
-	rb_ary_concat(ary, tmp);
+        rb_ary_concat(ary, tmp);
     }
     return Qnil;
 }
@@ -779,11 +779,11 @@ inject_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, p))
 
     ENUM_WANT_SVALUE();
 
-    if (memo->v1 == Qundef) {
-	MEMO_V1_SET(memo, i);
+    if (UNDEF_P(memo->v1)) {
+        MEMO_V1_SET(memo, i);
     }
     else {
-	MEMO_V1_SET(memo, rb_yield_values(2, memo->v1, i));
+        MEMO_V1_SET(memo, rb_yield_values(2, memo->v1, i));
     }
     return Qnil;
 }
@@ -796,18 +796,18 @@ inject_op_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, p))
 
     ENUM_WANT_SVALUE();
 
-    if (memo->v1 == Qundef) {
-	MEMO_V1_SET(memo, i);
+    if (UNDEF_P(memo->v1)) {
+        MEMO_V1_SET(memo, i);
     }
     else if (SYMBOL_P(name = memo->u3.value)) {
-	const ID mid = SYM2ID(name);
-	MEMO_V1_SET(memo, rb_funcallv_public(memo->v1, mid, 1, &i));
+        const ID mid = SYM2ID(name);
+        MEMO_V1_SET(memo, rb_funcallv_public(memo->v1, mid, 1, &i));
     }
     else {
-	VALUE args[2];
-	args[0] = name;
-	args[1] = i;
-	MEMO_V1_SET(memo, rb_f_send(numberof(args), args, memo->v1));
+        VALUE args[2];
+        args[0] = name;
+        args[1] = i;
+        MEMO_V1_SET(memo, rb_f_send(numberof(args), args, memo->v1));
     }
     return Qnil;
 }
@@ -820,9 +820,9 @@ ary_inject_op(VALUE ary, VALUE init, VALUE op)
     long i, n;
 
     if (RARRAY_LEN(ary) == 0)
-        return init == Qundef ? Qnil : init;
+        return UNDEF_P(init) ? Qnil : init;
 
-    if (init == Qundef) {
+    if (UNDEF_P(init)) {
         v = RARRAY_AREF(ary, 0);
         i = 1;
         if (RARRAY_LEN(ary) == 1)
@@ -835,9 +835,9 @@ ary_inject_op(VALUE ary, VALUE init, VALUE op)
 
     id = SYM2ID(op);
     if (id == idPLUS) {
-	if (RB_INTEGER_TYPE_P(v) &&
-	    rb_method_basic_definition_p(rb_cInteger, idPLUS) &&
-	    rb_obj_respond_to(v, idPLUS, FALSE)) {
+        if (RB_INTEGER_TYPE_P(v) &&
+            rb_method_basic_definition_p(rb_cInteger, idPLUS) &&
+            rb_obj_respond_to(v, idPLUS, FALSE)) {
             n = 0;
             for (; i < RARRAY_LEN(ary); i++) {
                 e = RARRAY_AREF(ary, i);
@@ -1021,25 +1021,25 @@ enum_inject(int argc, VALUE *argv, VALUE obj)
 
     switch (num_args) {
       case 0:
-	init = Qundef;
-	break;
+        init = Qundef;
+        break;
       case 1:
-	if (rb_block_given_p()) {
-	    break;
-	}
-	id = rb_check_id(&init);
-	op = id ? ID2SYM(id) : init;
-	init = Qundef;
-	iter = inject_op_i;
-	break;
+        if (rb_block_given_p()) {
+            break;
+        }
+        id = rb_check_id(&init);
+        op = id ? ID2SYM(id) : init;
+        init = Qundef;
+        iter = inject_op_i;
+        break;
       case 2:
-	if (rb_block_given_p()) {
-	    rb_warning("given block not used");
-	}
-	id = rb_check_id(&op);
-	if (id) op = ID2SYM(id);
-	iter = inject_op_i;
-	break;
+        if (rb_block_given_p()) {
+            rb_warning("given block not used");
+        }
+        id = rb_check_id(&op);
+        if (id) op = ID2SYM(id);
+        iter = inject_op_i;
+        break;
     }
 
     if (iter == inject_op_i &&
@@ -1051,7 +1051,7 @@ enum_inject(int argc, VALUE *argv, VALUE obj)
 
     memo = MEMO_NEW(init, Qnil, op);
     rb_block_call(obj, id_each, 0, 0, iter, (VALUE)memo);
-    if (memo->v1 == Qundef) return Qnil;
+    if (UNDEF_P(memo->v1)) return Qnil;
     return memo->v1;
 }
 
@@ -1063,10 +1063,10 @@ partition_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, arys))
     ENUM_WANT_SVALUE();
 
     if (RTEST(enum_yield(argc, i))) {
-	ary = memo->v1;
+        ary = memo->v1;
     }
     else {
-	ary = memo->v2;
+        ary = memo->v2;
     }
     rb_ary_push(ary, i);
     return Qnil;
@@ -1124,11 +1124,11 @@ group_by_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, hash))
     group = enum_yield(argc, i);
     values = rb_hash_aref(hash, group);
     if (!RB_TYPE_P(values, T_ARRAY)) {
-	values = rb_ary_new3(1, i);
-	rb_hash_aset(hash, group, values);
+        values = rb_ary_new3(1, i);
+        rb_hash_aset(hash, group, values);
     }
     else {
-	rb_ary_push(values, i);
+        rb_ary_push(values, i);
     }
     return Qnil;
 }
@@ -1288,12 +1288,12 @@ enum_first(int argc, VALUE *argv, VALUE obj)
     struct MEMO *memo;
     rb_check_arity(argc, 0, 1);
     if (argc > 0) {
-	return enum_take(obj, argv[0]);
+        return enum_take(obj, argv[0]);
     }
     else {
-	memo = MEMO_NEW(Qnil, 0, 0);
-	rb_block_call(obj, id_each, 0, 0, first_i, (VALUE)memo);
-	return memo->v1;
+        memo = MEMO_NEW(Qnil, 0, 0);
+        rb_block_call(obj, id_each, 0, 0, first_i, (VALUE)memo);
+        return memo->v1;
     }
 }
 
@@ -1354,18 +1354,18 @@ sort_by_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, _data))
     v = enum_yield(argc, i);
 
     if (RBASIC(ary)->klass) {
-	rb_raise(rb_eRuntimeError, "sort_by reentered");
+        rb_raise(rb_eRuntimeError, "sort_by reentered");
     }
     if (RARRAY_LEN(data->buf) != SORT_BY_BUFSIZE*2) {
-	rb_raise(rb_eRuntimeError, "sort_by reentered");
+        rb_raise(rb_eRuntimeError, "sort_by reentered");
     }
 
     RARRAY_ASET(data->buf, data->n*2, v);
     RARRAY_ASET(data->buf, data->n*2+1, i);
     data->n++;
     if (data->n == SORT_BY_BUFSIZE) {
-	rb_ary_concat(ary, data->buf);
-	data->n = 0;
+        rb_ary_concat(ary, data->buf);
+        data->n = 0;
     }
     return Qnil;
 }
@@ -1373,19 +1373,18 @@ sort_by_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, _data))
 static int
 sort_by_cmp(const void *ap, const void *bp, void *data)
 {
-    struct cmp_opt_data cmp_opt = { 0, 0 };
     VALUE a;
     VALUE b;
     VALUE ary = (VALUE)data;
 
     if (RBASIC(ary)->klass) {
-	rb_raise(rb_eRuntimeError, "sort_by reentered");
+        rb_raise(rb_eRuntimeError, "sort_by reentered");
     }
 
     a = *(VALUE *)ap;
     b = *(VALUE *)bp;
 
-    return OPTIMIZED_CMP(a, b, cmp_opt);
+    return OPTIMIZED_CMP(a, b);
 }
 
 /*
@@ -1481,13 +1480,13 @@ enum_sort_by(VALUE obj)
     RETURN_SIZED_ENUMERATOR(obj, 0, 0, enum_size);
 
     if (RB_TYPE_P(obj, T_ARRAY) && RARRAY_LEN(obj) <= LONG_MAX/2) {
-	ary = rb_ary_new2(RARRAY_LEN(obj)*2);
+        ary = rb_ary_new2(RARRAY_LEN(obj)*2);
     }
     else {
-	ary = rb_ary_new();
+        ary = rb_ary_new();
     }
     RBASIC_CLEAR_CLASS(ary);
-    buf = rb_ary_tmp_new(SORT_BY_BUFSIZE*2);
+    buf = rb_ary_hidden_new(SORT_BY_BUFSIZE*2);
     rb_ary_store(buf, SORT_BY_BUFSIZE*2-1, Qnil);
     memo = MEMO_NEW(0, 0, 0);
     data = (struct sort_by_data *)&memo->v1;
@@ -1498,8 +1497,8 @@ enum_sort_by(VALUE obj)
     ary = data->ary;
     buf = data->buf;
     if (data->n) {
-	rb_ary_resize(buf, data->n*2);
-	rb_ary_concat(ary, buf);
+        rb_ary_resize(buf, data->n*2);
+        rb_ary_concat(ary, buf);
     }
     if (RARRAY_LEN(ary) > 2) {
         RARRAY_PTR_USE(ary, ptr,
@@ -1507,10 +1506,10 @@ enum_sort_by(VALUE obj)
                                   sort_by_cmp, (void *)ary));
     }
     if (RBASIC(ary)->klass) {
-	rb_raise(rb_eRuntimeError, "sort_by reentered");
+        rb_raise(rb_eRuntimeError, "sort_by reentered");
     }
     for (i=1; i<RARRAY_LEN(ary); i+=2) {
-	RARRAY_ASET(ary, i/2, RARRAY_AREF(ary, i));
+        RARRAY_ASET(ary, i/2, RARRAY_AREF(ary, i));
     }
     rb_ary_resize(ary, RARRAY_LEN(ary)/2);
     RBASIC_SET_CLASS_RAW(ary, rb_cArray);
@@ -1556,8 +1555,8 @@ enum_##name##_func(VALUE result, struct MEMO *memo)
 DEFINE_ENUMFUNCS(all)
 {
     if (!RTEST(result)) {
-	MEMO_V1_SET(memo, Qfalse);
-	rb_iter_break();
+        MEMO_V1_SET(memo, Qfalse);
+        rb_iter_break();
     }
     return Qnil;
 }
@@ -1617,8 +1616,8 @@ enum_all(int argc, VALUE *argv, VALUE obj)
 DEFINE_ENUMFUNCS(any)
 {
     if (RTEST(result)) {
-	MEMO_V1_SET(memo, Qtrue);
-	rb_iter_break();
+        MEMO_V1_SET(memo, Qtrue);
+        rb_iter_break();
     }
     return Qnil;
 }
@@ -1677,13 +1676,13 @@ enum_any(int argc, VALUE *argv, VALUE obj)
 DEFINE_ENUMFUNCS(one)
 {
     if (RTEST(result)) {
-	if (memo->v1 == Qundef) {
-	    MEMO_V1_SET(memo, Qtrue);
-	}
-	else if (memo->v1 == Qtrue) {
-	    MEMO_V1_SET(memo, Qfalse);
-	    rb_iter_break();
-	}
+        if (UNDEF_P(memo->v1)) {
+            MEMO_V1_SET(memo, Qtrue);
+        }
+        else if (memo->v1 == Qtrue) {
+            MEMO_V1_SET(memo, Qfalse);
+            rb_iter_break();
+        }
     }
     return Qnil;
 }
@@ -1713,11 +1712,10 @@ cmpint_reenter_check(struct nmin_data *data, VALUE val)
 static int
 nmin_cmp(const void *ap, const void *bp, void *_data)
 {
-    struct cmp_opt_data cmp_opt = { 0, 0 };
     struct nmin_data *data = (struct nmin_data *)_data;
     VALUE a = *(const VALUE *)ap, b = *(const VALUE *)bp;
 #define rb_cmpint(cmp, a, b) rb_cmpint(cmpint_reenter_check(data, (cmp)), a, b)
-    return OPTIMIZED_CMP(a, b, cmp_opt);
+    return OPTIMIZED_CMP(a, b);
 #undef rb_cmpint
 }
 
@@ -1745,7 +1743,7 @@ nmin_filter(struct nmin_data *data)
     long i, j;
 
     if (data->curlen <= data->n)
-	return;
+        return;
 
     n = data->n;
     beg = RARRAY_PTR(data->buf);
@@ -1765,46 +1763,46 @@ nmin_filter(struct nmin_data *data)
 } while (0)
 
     while (1) {
-	long pivot_index = left + (right-left)/2;
-	long num_pivots = 1;
-
-	SWAP(pivot_index, right);
-	pivot_index = right;
-
-	store_index = left;
-	i = left;
-	while (i <= right-num_pivots) {
-	    int c = data->cmpfunc(GETPTR(i), GETPTR(pivot_index), data);
-	    if (data->rev)
-		c = -c;
-	    if (c == 0) {
-	        SWAP(i, right-num_pivots);
-		num_pivots++;
-		continue;
-	    }
-	    if (c < 0) {
-		SWAP(i, store_index);
-		store_index++;
-	    }
-	    i++;
-	}
-	j = store_index;
-	for (i = right; right-num_pivots < i; i--) {
-	    if (i <= j)
-	        break;
-	    SWAP(j, i);
-	    j++;
-	}
-
-	if (store_index <= n && n <= store_index+num_pivots)
-	    break;
-
-	if (n < store_index) {
-	    right = store_index-1;
-	}
-	else {
-	    left = store_index+num_pivots;
-	}
+        long pivot_index = left + (right-left)/2;
+        long num_pivots = 1;
+
+        SWAP(pivot_index, right);
+        pivot_index = right;
+
+        store_index = left;
+        i = left;
+        while (i <= right-num_pivots) {
+            int c = data->cmpfunc(GETPTR(i), GETPTR(pivot_index), data);
+            if (data->rev)
+                c = -c;
+            if (c == 0) {
+                SWAP(i, right-num_pivots);
+                num_pivots++;
+                continue;
+            }
+            if (c < 0) {
+                SWAP(i, store_index);
+                store_index++;
+            }
+            i++;
+        }
+        j = store_index;
+        for (i = right; right-num_pivots < i; i--) {
+            if (i <= j)
+                break;
+            SWAP(j, i);
+            j++;
+        }
+
+        if (store_index <= n && n <= store_index+num_pivots)
+            break;
+
+        if (n < store_index) {
+            right = store_index-1;
+        }
+        else {
+            left = store_index+num_pivots;
+        }
     }
 #undef GETPTR
 #undef SWAP
@@ -1823,11 +1821,11 @@ nmin_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, _data))
     ENUM_WANT_SVALUE();
 
     if (data->by)
-	cmpv = enum_yield(argc, i);
+        cmpv = enum_yield(argc, i);
     else
-	cmpv = i;
+        cmpv = i;
 
-    if (data->limit != Qundef) {
+    if (!UNDEF_P(data->limit)) {
         int c = data->cmpfunc(&cmpv, &data->limit, data);
         if (data->rev)
             c = -c;
@@ -1836,13 +1834,13 @@ nmin_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, _data))
     }
 
     if (data->by)
-	rb_ary_push(data->buf, cmpv);
+        rb_ary_push(data->buf, cmpv);
     rb_ary_push(data->buf, i);
 
     data->curlen++;
 
     if (data->curlen == data->bufmax) {
-	nmin_filter(data);
+        nmin_filter(data);
     }
 
     return Qnil;
@@ -1863,28 +1861,28 @@ rb_nmin_run(VALUE obj, VALUE num, int by, int rev, int ary)
         rb_raise(rb_eArgError, "too big size");
     data.bufmax = data.n * 4;
     data.curlen = 0;
-    data.buf = rb_ary_tmp_new(data.bufmax * (by ? 2 : 1));
+    data.buf = rb_ary_hidden_new(data.bufmax * (by ? 2 : 1));
     data.limit = Qundef;
     data.cmpfunc = by ? nmin_cmp :
                    rb_block_given_p() ? nmin_block_cmp :
-		   nmin_cmp;
+                   nmin_cmp;
     data.rev = rev;
     data.by = by;
     if (ary) {
-	long i;
-	for (i = 0; i < RARRAY_LEN(obj); i++) {
-	    VALUE args[1];
-	    args[0] = RARRAY_AREF(obj, i);
+        long i;
+        for (i = 0; i < RARRAY_LEN(obj); i++) {
+            VALUE args[1];
+            args[0] = RARRAY_AREF(obj, i);
             nmin_i(obj, (VALUE)&data, 1, args, Qundef);
-	}
+        }
     }
     else {
-	rb_block_call(obj, id_each, 0, 0, nmin_i, (VALUE)&data);
+        rb_block_call(obj, id_each, 0, 0, nmin_i, (VALUE)&data);
     }
     nmin_filter(&data);
     result = data.buf;
     if (by) {
-	long i;
+        long i;
         RARRAY_PTR_USE(result, ptr, {
             ruby_qsort(ptr,
                        RARRAY_LEN(result)/2,
@@ -1894,7 +1892,7 @@ rb_nmin_run(VALUE obj, VALUE num, int by, int rev, int ary)
                 ptr[i/2] = ptr[i];
             }
         });
-	rb_ary_resize(result, RARRAY_LEN(result)/2);
+        rb_ary_resize(result, RARRAY_LEN(result)/2);
     }
     else {
         RARRAY_PTR_USE(result, ptr, {
@@ -1962,15 +1960,15 @@ enum_one(int argc, VALUE *argv, VALUE obj)
     WARN_UNUSED_BLOCK(argc);
     rb_block_call(obj, id_each, 0, 0, ENUMFUNC(one), (VALUE)memo);
     result = memo->v1;
-    if (result == Qundef) return Qfalse;
+    if (UNDEF_P(result)) return Qfalse;
     return result;
 }
 
 DEFINE_ENUMFUNCS(none)
 {
     if (RTEST(result)) {
-	MEMO_V1_SET(memo, Qfalse);
-	rb_iter_break();
+        MEMO_V1_SET(memo, Qfalse);
+        rb_iter_break();
     }
     return Qnil;
 }
@@ -2027,7 +2025,6 @@ enum_none(int argc, VALUE *argv, VALUE obj)
 
 struct min_t {
     VALUE min;
-    struct cmp_opt_data cmp_opt;
 };
 
 static VALUE
@@ -2037,13 +2034,13 @@ min_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, args))
 
     ENUM_WANT_SVALUE();
 
-    if (memo->min == Qundef) {
-	memo->min = i;
+    if (UNDEF_P(memo->min)) {
+        memo->min = i;
     }
     else {
-	if (OPTIMIZED_CMP(i, memo->min, memo->cmp_opt) < 0) {
-	    memo->min = i;
-	}
+        if (OPTIMIZED_CMP(i, memo->min) < 0) {
+            memo->min = i;
+        }
     }
     return Qnil;
 }
@@ -2056,14 +2053,14 @@ min_ii(RB_BLOCK_CALL_FUNC_ARGLIST(i, args))
 
     ENUM_WANT_SVALUE();
 
-    if (memo->min == Qundef) {
-	memo->min = i;
+    if (UNDEF_P(memo->min)) {
+        memo->min = i;
     }
     else {
-	cmp = rb_yield_values(2, i, memo->min);
-	if (rb_cmpint(cmp, i, memo->min) < 0) {
-	    memo->min = i;
-	}
+        cmp = rb_yield_values(2, i, memo->min);
+        if (rb_cmpint(cmp, i, memo->min) < 0) {
+            memo->min = i;
+        }
     }
     return Qnil;
 }
@@ -2130,7 +2127,7 @@ static VALUE
 enum_min(int argc, VALUE *argv, VALUE obj)
 {
     VALUE memo;
-    struct min_t *m = NEW_CMP_OPT_MEMO(struct min_t, memo);
+    struct min_t *m = NEW_MEMO_FOR(struct min_t, memo);
     VALUE result;
     VALUE num;
 
@@ -2138,22 +2135,19 @@ enum_min(int argc, VALUE *argv, VALUE obj)
        return rb_nmin_run(obj, num, 0, 0, 0);
 
     m->min = Qundef;
-    m->cmp_opt.opt_methods = 0;
-    m->cmp_opt.opt_inited = 0;
     if (rb_block_given_p()) {
-	rb_block_call(obj, id_each, 0, 0, min_ii, memo);
+        rb_block_call(obj, id_each, 0, 0, min_ii, memo);
     }
     else {
-	rb_block_call(obj, id_each, 0, 0, min_i, memo);
+        rb_block_call(obj, id_each, 0, 0, min_i, memo);
     }
     result = m->min;
-    if (result == Qundef) return Qnil;
+    if (UNDEF_P(result)) return Qnil;
     return result;
 }
 
 struct max_t {
     VALUE max;
-    struct cmp_opt_data cmp_opt;
 };
 
 static VALUE
@@ -2163,13 +2157,13 @@ max_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, args))
 
     ENUM_WANT_SVALUE();
 
-    if (memo->max == Qundef) {
-	memo->max = i;
+    if (UNDEF_P(memo->max)) {
+        memo->max = i;
     }
     else {
-	if (OPTIMIZED_CMP(i, memo->max, memo->cmp_opt) > 0) {
-	    memo->max = i;
-	}
+        if (OPTIMIZED_CMP(i, memo->max) > 0) {
+            memo->max = i;
+        }
     }
     return Qnil;
 }
@@ -2182,14 +2176,14 @@ max_ii(RB_BLOCK_CALL_FUNC_ARGLIST(i, args))
 
     ENUM_WANT_SVALUE();
 
-    if (memo->max == Qundef) {
-	memo->max = i;
+    if (UNDEF_P(memo->max)) {
+        memo->max = i;
     }
     else {
-	cmp = rb_yield_values(2, i, memo->max);
-	if (rb_cmpint(cmp, i, memo->max) > 0) {
-	    memo->max = i;
-	}
+        cmp = rb_yield_values(2, i, memo->max);
+        if (rb_cmpint(cmp, i, memo->max) > 0) {
+            memo->max = i;
+        }
     }
     return Qnil;
 }
@@ -2255,7 +2249,7 @@ static VALUE
 enum_max(int argc, VALUE *argv, VALUE obj)
 {
     VALUE memo;
-    struct max_t *m = NEW_CMP_OPT_MEMO(struct max_t, memo);
+    struct max_t *m = NEW_MEMO_FOR(struct max_t, memo);
     VALUE result;
     VALUE num;
 
@@ -2263,16 +2257,14 @@ enum_max(int argc, VALUE *argv, VALUE obj)
        return rb_nmin_run(obj, num, 0, 1, 0);
 
     m->max = Qundef;
-    m->cmp_opt.opt_methods = 0;
-    m->cmp_opt.opt_inited = 0;
     if (rb_block_given_p()) {
-	rb_block_call(obj, id_each, 0, 0, max_ii, (VALUE)memo);
+        rb_block_call(obj, id_each, 0, 0, max_ii, (VALUE)memo);
     }
     else {
-	rb_block_call(obj, id_each, 0, 0, max_i, (VALUE)memo);
+        rb_block_call(obj, id_each, 0, 0, max_i, (VALUE)memo);
     }
     result = m->max;
-    if (result == Qundef) return Qnil;
+    if (UNDEF_P(result)) return Qnil;
     return result;
 }
 
@@ -2280,7 +2272,6 @@ struct minmax_t {
     VALUE min;
     VALUE max;
     VALUE last;
-    struct cmp_opt_data cmp_opt;
 };
 
 static void
@@ -2288,19 +2279,19 @@ minmax_i_update(VALUE i, VALUE j, struct minmax_t *memo)
 {
     int n;
 
-    if (memo->min == Qundef) {
-	memo->min = i;
-	memo->max = j;
+    if (UNDEF_P(memo->min)) {
+        memo->min = i;
+        memo->max = j;
     }
     else {
-	n = OPTIMIZED_CMP(i, memo->min, memo->cmp_opt);
-	if (n < 0) {
-	    memo->min = i;
-	}
-	n = OPTIMIZED_CMP(j, memo->max, memo->cmp_opt);
-	if (n > 0) {
-	    memo->max = j;
-	}
+        n = OPTIMIZED_CMP(i, memo->min);
+        if (n < 0) {
+            memo->min = i;
+        }
+        n = OPTIMIZED_CMP(j, memo->max);
+        if (n > 0) {
+            memo->max = j;
+        }
     }
 }
 
@@ -2313,14 +2304,14 @@ minmax_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, _memo))
 
     ENUM_WANT_SVALUE();
 
-    if (memo->last == Qundef) {
+    if (UNDEF_P(memo->last)) {
         memo->last = i;
         return Qnil;
     }
     j = memo->last;
     memo->last = Qundef;
 
-    n = OPTIMIZED_CMP(j, i, memo->cmp_opt);
+    n = OPTIMIZED_CMP(j, i);
     if (n == 0)
         i = j;
     else if (n < 0) {
@@ -2340,19 +2331,19 @@ minmax_ii_update(VALUE i, VALUE j, struct minmax_t *memo)
 {
     int n;
 
-    if (memo->min == Qundef) {
-	memo->min = i;
-	memo->max = j;
+    if (UNDEF_P(memo->min)) {
+        memo->min = i;
+        memo->max = j;
     }
     else {
-	n = rb_cmpint(rb_yield_values(2, i, memo->min), i, memo->min);
-	if (n < 0) {
-	    memo->min = i;
-	}
-	n = rb_cmpint(rb_yield_values(2, j, memo->max), j, memo->max);
-	if (n > 0) {
-	    memo->max = j;
-	}
+        n = rb_cmpint(rb_yield_values(2, i, memo->min), i, memo->min);
+        if (n < 0) {
+            memo->min = i;
+        }
+        n = rb_cmpint(rb_yield_values(2, j, memo->max), j, memo->max);
+        if (n > 0) {
+            memo->max = j;
+        }
     }
 }
 
@@ -2365,7 +2356,7 @@ minmax_ii(RB_BLOCK_CALL_FUNC_ARGLIST(i, _memo))
 
     ENUM_WANT_SVALUE();
 
-    if (memo->last == Qundef) {
+    if (UNDEF_P(memo->last)) {
         memo->last = i;
         return Qnil;
     }
@@ -2422,24 +2413,22 @@ static VALUE
 enum_minmax(VALUE obj)
 {
     VALUE memo;
-    struct minmax_t *m = NEW_CMP_OPT_MEMO(struct minmax_t, memo);
+    struct minmax_t *m = NEW_MEMO_FOR(struct minmax_t, memo);
 
     m->min = Qundef;
     m->last = Qundef;
-    m->cmp_opt.opt_methods = 0;
-    m->cmp_opt.opt_inited = 0;
     if (rb_block_given_p()) {
-	rb_block_call(obj, id_each, 0, 0, minmax_ii, memo);
-	if (m->last != Qundef)
-	    minmax_ii_update(m->last, m->last, m);
+        rb_block_call(obj, id_each, 0, 0, minmax_ii, memo);
+        if (!UNDEF_P(m->last))
+            minmax_ii_update(m->last, m->last, m);
     }
     else {
-	rb_block_call(obj, id_each, 0, 0, minmax_i, memo);
-	if (m->last != Qundef)
-	    minmax_i_update(m->last, m->last, m);
+        rb_block_call(obj, id_each, 0, 0, minmax_i, memo);
+        if (!UNDEF_P(m->last))
+            minmax_i_update(m->last, m->last, m);
     }
-    if (m->min != Qundef) {
-	return rb_assoc_new(m->min, m->max);
+    if (!UNDEF_P(m->min)) {
+        return rb_assoc_new(m->min, m->max);
     }
     return rb_assoc_new(Qnil, Qnil);
 }
@@ -2447,20 +2436,19 @@ enum_minmax(VALUE obj)
 static VALUE
 min_by_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, args))
 {
-    struct cmp_opt_data cmp_opt = { 0, 0 };
     struct MEMO *memo = MEMO_CAST(args);
     VALUE v;
 
     ENUM_WANT_SVALUE();
 
     v = enum_yield(argc, i);
-    if (memo->v1 == Qundef) {
-	MEMO_V1_SET(memo, v);
-	MEMO_V2_SET(memo, i);
+    if (UNDEF_P(memo->v1)) {
+        MEMO_V1_SET(memo, v);
+        MEMO_V2_SET(memo, i);
     }
-    else if (OPTIMIZED_CMP(v, memo->v1, cmp_opt) < 0) {
-	MEMO_V1_SET(memo, v);
-	MEMO_V2_SET(memo, i);
+    else if (OPTIMIZED_CMP(v, memo->v1) < 0) {
+        MEMO_V1_SET(memo, v);
+        MEMO_V2_SET(memo, i);
     }
     return Qnil;
 }
@@ -2522,20 +2510,19 @@ enum_min_by(int argc, VALUE *argv, VALUE obj)
 static VALUE
 max_by_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, args))
 {
-    struct cmp_opt_data cmp_opt = { 0, 0 };
     struct MEMO *memo = MEMO_CAST(args);
     VALUE v;
 
     ENUM_WANT_SVALUE();
 
     v = enum_yield(argc, i);
-    if (memo->v1 == Qundef) {
-	MEMO_V1_SET(memo, v);
-	MEMO_V2_SET(memo, i);
+    if (UNDEF_P(memo->v1)) {
+        MEMO_V1_SET(memo, v);
+        MEMO_V2_SET(memo, i);
     }
-    else if (OPTIMIZED_CMP(v, memo->v1, cmp_opt) > 0) {
-	MEMO_V1_SET(memo, v);
-	MEMO_V2_SET(memo, i);
+    else if (OPTIMIZED_CMP(v, memo->v1) > 0) {
+        MEMO_V1_SET(memo, v);
+        MEMO_V2_SET(memo, i);
     }
     return Qnil;
 }
@@ -2606,30 +2593,27 @@ struct minmax_by_t {
 static void
 minmax_by_i_update(VALUE v1, VALUE v2, VALUE i1, VALUE i2, struct minmax_by_t *memo)
 {
-    struct cmp_opt_data cmp_opt = { 0, 0 };
-
-    if (memo->min_bv == Qundef) {
-	memo->min_bv = v1;
-	memo->max_bv = v2;
-	memo->min = i1;
-	memo->max = i2;
+    if (UNDEF_P(memo->min_bv)) {
+        memo->min_bv = v1;
+        memo->max_bv = v2;
+        memo->min = i1;
+        memo->max = i2;
     }
     else {
-	if (OPTIMIZED_CMP(v1, memo->min_bv, cmp_opt) < 0) {
-	    memo->min_bv = v1;
-	    memo->min = i1;
-	}
-	if (OPTIMIZED_CMP(v2, memo->max_bv, cmp_opt) > 0) {
-	    memo->max_bv = v2;
-	    memo->max = i2;
-	}
+        if (OPTIMIZED_CMP(v1, memo->min_bv) < 0) {
+            memo->min_bv = v1;
+            memo->min = i1;
+        }
+        if (OPTIMIZED_CMP(v2, memo->max_bv) > 0) {
+            memo->max_bv = v2;
+            memo->max = i2;
+        }
     }
 }
 
 static VALUE
 minmax_by_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, _memo))
 {
-    struct cmp_opt_data cmp_opt = { 0, 0 };
     struct minmax_by_t *memo = MEMO_FOR(struct minmax_by_t, _memo);
     VALUE vi, vj, j;
     int n;
@@ -2638,7 +2622,7 @@ minmax_by_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, _memo))
 
     vi = enum_yield(argc, i);
 
-    if (memo->last_bv == Qundef) {
+    if (UNDEF_P(memo->last_bv)) {
         memo->last_bv = vi;
         memo->last = i;
         return Qnil;
@@ -2647,7 +2631,7 @@ minmax_by_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, _memo))
     j = memo->last;
     memo->last_bv = Qundef;
 
-    n = OPTIMIZED_CMP(vj, vi, cmp_opt);
+    n = OPTIMIZED_CMP(vj, vi);
     if (n == 0) {
         i = j;
         vi = vj;
@@ -2705,7 +2689,7 @@ enum_minmax_by(VALUE obj)
     m->last_bv = Qundef;
     m->last = Qundef;
     rb_block_call(obj, id_each, 0, 0, minmax_by_i, memo);
-    if (m->last_bv != Qundef)
+    if (!UNDEF_P(m->last_bv))
         minmax_by_i_update(m->last_bv, m->last_bv, m->last, m->last, m);
     m = MEMO_FOR(struct minmax_by_t, memo);
     return rb_assoc_new(m->min, m->max);
@@ -2717,8 +2701,8 @@ member_i(RB_BLOCK_CALL_FUNC_ARGLIST(iter, args))
     struct MEMO *memo = MEMO_CAST(args);
 
     if (rb_equal(rb_enum_values_pack(argc, argv), memo->v1)) {
-	MEMO_V2_SET(memo, Qtrue);
-	rb_iter_break();
+        MEMO_V2_SET(memo, Qtrue);
+        rb_iter_break();
     }
     return Qnil;
 }
@@ -2935,14 +2919,14 @@ each_slice_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, m))
     rb_ary_push(ary, i);
 
     if (RARRAY_LEN(ary) == size) {
-	v = rb_yield(ary);
+        v = rb_yield(ary);
 
-	if (memo->v2) {
-	    MEMO_V1_SET(memo, rb_ary_new2(size));
-	}
-	else {
-	    rb_ary_clear(ary);
-	}
+        if (memo->v2) {
+            MEMO_V1_SET(memo, rb_ary_new2(size));
+        }
+        else {
+            rb_ary_clear(ary);
+        }
     }
 
     return v;
@@ -3018,14 +3002,14 @@ each_cons_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, args))
     ENUM_WANT_SVALUE();
 
     if (RARRAY_LEN(ary) == size) {
-	rb_ary_shift(ary);
+        rb_ary_shift(ary);
     }
     rb_ary_push(ary, i);
     if (RARRAY_LEN(ary) == size) {
-	if (memo->v2) {
-	    ary = rb_ary_dup(ary);
-	}
-	v = rb_yield(ary);
+        if (memo->v2) {
+            ary = rb_ary_dup(ary);
+        }
+        v = rb_yield(ary);
     }
     return v;
 }
@@ -3033,7 +3017,6 @@ each_cons_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, args))
 static VALUE
 enum_each_cons_size(VALUE obj, VALUE args, VALUE eobj)
 {
-    struct cmp_opt_data cmp_opt = { 0, 0 };
     const VALUE zero = LONG2FIX(0);
     VALUE n, size;
     long cons_size = NUM2LONG(RARRAY_AREF(args, 0));
@@ -3043,7 +3026,7 @@ enum_each_cons_size(VALUE obj, VALUE args, VALUE eobj)
     if (NIL_P(size)) return Qnil;
 
     n = add_int(size, 1 - cons_size);
-    return (OPTIMIZED_CMP(n, zero, cmp_opt) == -1) ? zero : n;
+    return (OPTIMIZED_CMP(n, zero) == -1) ? zero : n;
 }
 
 /*
@@ -3098,8 +3081,10 @@ each_with_object_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, memo))
  *  Calls the block once for each element, passing both the element
  *  and the given object:
  *
- *    (1..4).each_with_object([]) {|i, a| a.push(i**2) } # => [1, 4, 9, 16]
- *    h.each_with_object({}) {|element, h| k, v = *element; h[v] = k }
+ *    (1..4).each_with_object([]) {|i, a| a.push(i**2) }
+ *    # => [1, 4, 9, 16]
+ *
+ *    {foo: 0, bar: 1, baz: 2}.each_with_object({}) {|(k, v), h| h[v] = k }
  *    # => {0=>:foo, 1=>:bar, 2=>:baz}
  *
  *  With no block given, returns an Enumerator.
@@ -3128,20 +3113,20 @@ zip_ary(RB_BLOCK_CALL_FUNC_ARGLIST(val, memoval))
     tmp = rb_ary_new2(RARRAY_LEN(args) + 1);
     rb_ary_store(tmp, 0, rb_enum_values_pack(argc, argv));
     for (i=0; i<RARRAY_LEN(args); i++) {
-	VALUE e = RARRAY_AREF(args, i);
+        VALUE e = RARRAY_AREF(args, i);
 
-	if (RARRAY_LEN(e) <= n) {
-	    rb_ary_push(tmp, Qnil);
-	}
-	else {
-	    rb_ary_push(tmp, RARRAY_AREF(e, n));
-	}
+        if (RARRAY_LEN(e) <= n) {
+            rb_ary_push(tmp, Qnil);
+        }
+        else {
+            rb_ary_push(tmp, RARRAY_AREF(e, n));
+        }
     }
     if (NIL_P(result)) {
-	enum_yield_array(tmp);
+        enum_yield_array(tmp);
     }
     else {
-	rb_ary_push(result, tmp);
+        rb_ary_push(result, tmp);
     }
 
     RB_GC_GUARD(args);
@@ -3175,26 +3160,26 @@ zip_i(RB_BLOCK_CALL_FUNC_ARGLIST(val, memoval))
     tmp = rb_ary_new2(RARRAY_LEN(args) + 1);
     rb_ary_store(tmp, 0, rb_enum_values_pack(argc, argv));
     for (i=0; i<RARRAY_LEN(args); i++) {
-	if (NIL_P(RARRAY_AREF(args, i))) {
-	    rb_ary_push(tmp, Qnil);
-	}
-	else {
-	    VALUE v[2];
-
-	    v[1] = RARRAY_AREF(args, i);
-	    rb_rescue2(call_next, (VALUE)v, call_stop, (VALUE)v, rb_eStopIteration, (VALUE)0);
-	    if (v[0] == Qundef) {
-		RARRAY_ASET(args, i, Qnil);
-		v[0] = Qnil;
-	    }
-	    rb_ary_push(tmp, v[0]);
-	}
+        if (NIL_P(RARRAY_AREF(args, i))) {
+            rb_ary_push(tmp, Qnil);
+        }
+        else {
+            VALUE v[2];
+
+            v[1] = RARRAY_AREF(args, i);
+            rb_rescue2(call_next, (VALUE)v, call_stop, (VALUE)v, rb_eStopIteration, (VALUE)0);
+            if (UNDEF_P(v[0])) {
+                RARRAY_ASET(args, i, Qnil);
+                v[0] = Qnil;
+            }
+            rb_ary_push(tmp, v[0]);
+        }
     }
     if (NIL_P(result)) {
-	enum_yield_array(tmp);
+        enum_yield_array(tmp);
     }
     else {
-	rb_ary_push(result, tmp);
+        rb_ary_push(result, tmp);
     }
 
     RB_GC_GUARD(args);
@@ -3281,26 +3266,26 @@ enum_zip(int argc, VALUE *argv, VALUE obj)
 
     argv = RARRAY_PTR(args);
     for (i=0; i<argc; i++) {
-	VALUE ary = rb_check_array_type(argv[i]);
-	if (NIL_P(ary)) {
-	    allary = FALSE;
-	    break;
-	}
-	argv[i] = ary;
+        VALUE ary = rb_check_array_type(argv[i]);
+        if (NIL_P(ary)) {
+            allary = FALSE;
+            break;
+        }
+        argv[i] = ary;
     }
     if (!allary) {
-	static const VALUE sym_each = STATIC_ID2SYM(id_each);
-	CONST_ID(conv, "to_enum");
-	for (i=0; i<argc; i++) {
-	    if (!rb_respond_to(argv[i], id_each)) {
-		rb_raise(rb_eTypeError, "wrong argument type %"PRIsVALUE" (must respond to :each)",
-			 rb_obj_class(argv[i]));
+        static const VALUE sym_each = STATIC_ID2SYM(id_each);
+        CONST_ID(conv, "to_enum");
+        for (i=0; i<argc; i++) {
+            if (!rb_respond_to(argv[i], id_each)) {
+                rb_raise(rb_eTypeError, "wrong argument type %"PRIsVALUE" (must respond to :each)",
+                         rb_obj_class(argv[i]));
             }
-	    argv[i] = rb_funcallv(argv[i], conv, 1, &sym_each);
-	}
+            argv[i] = rb_funcallv(argv[i], conv, 1, &sym_each);
+        }
     }
     if (!rb_block_given_p()) {
-	result = rb_ary_new();
+        result = rb_ary_new();
     }
 
     /* TODO: use NODE_DOT2 as memo(v, v, -) */
@@ -3342,7 +3327,7 @@ enum_take(VALUE obj, VALUE n)
     long len = NUM2LONG(n);
 
     if (len < 0) {
-	rb_raise(rb_eArgError, "attempt to take negative size");
+        rb_raise(rb_eArgError, "attempt to take negative size");
     }
 
     if (len == 0) return rb_ary_new2(0);
@@ -3396,10 +3381,10 @@ drop_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, args))
 {
     struct MEMO *memo = MEMO_CAST(args);
     if (memo->u3.cnt == 0) {
-	rb_ary_push(memo->v1, rb_enum_values_pack(argc, argv));
+        rb_ary_push(memo->v1, rb_enum_values_pack(argc, argv));
     }
     else {
-	memo->u3.cnt--;
+        memo->u3.cnt--;
     }
     return Qnil;
 }
@@ -3431,7 +3416,7 @@ enum_drop(VALUE obj, VALUE n)
     long len = NUM2LONG(n);
 
     if (len < 0) {
-	rb_raise(rb_eArgError, "attempt to drop negative size");
+        rb_raise(rb_eArgError, "attempt to drop negative size");
     }
 
     result = rb_ary_new();
@@ -3448,10 +3433,10 @@ drop_while_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, args))
     ENUM_WANT_SVALUE();
 
     if (!memo->u3.state && !RTEST(enum_yield(argc, i))) {
-	memo->u3.state = TRUE;
+        memo->u3.state = TRUE;
     }
     if (memo->u3.state) {
-	rb_ary_push(memo->v1, i);
+        rb_ary_push(memo->v1, i);
     }
     return Qnil;
 }
@@ -3506,8 +3491,8 @@ enum_cycle_size(VALUE self, VALUE args, VALUE eobj)
     VALUE size;
 
     if (args && (RARRAY_LEN(args) > 0)) {
-	n = RARRAY_AREF(args, 0);
-	if (!NIL_P(n)) mul = NUM2LONG(n);
+        n = RARRAY_AREF(args, 0);
+        if (!NIL_P(n)) mul = NUM2LONG(n);
     }
 
     size = enum_size(self, args, 0);
@@ -3570,7 +3555,7 @@ enum_cycle(int argc, VALUE *argv, VALUE obj)
     if (len == 0) return Qnil;
     while (n < 0 || 0 < --n) {
         for (i=0; i<len; i++) {
-	    enum_yield_array(RARRAY_AREF(ary, i));
+            enum_yield_array(RARRAY_AREF(ary, i));
         }
     }
     return Qnil;
@@ -3597,22 +3582,22 @@ chunk_ii(RB_BLOCK_CALL_FUNC_ARGLIST(i, _argp))
 
     if (v == alone) {
         if (!NIL_P(argp->prev_value)) {
-	    s = rb_assoc_new(argp->prev_value, argp->prev_elts);
+            s = rb_assoc_new(argp->prev_value, argp->prev_elts);
             rb_funcallv(argp->yielder, id_lshift, 1, &s);
             argp->prev_value = argp->prev_elts = Qnil;
         }
-	v = rb_assoc_new(v, rb_ary_new3(1, i));
+        v = rb_assoc_new(v, rb_ary_new3(1, i));
         rb_funcallv(argp->yielder, id_lshift, 1, &v);
     }
     else if (NIL_P(v) || v == separator) {
         if (!NIL_P(argp->prev_value)) {
-	    v = rb_assoc_new(argp->prev_value, argp->prev_elts);
+            v = rb_assoc_new(argp->prev_value, argp->prev_elts);
             rb_funcallv(argp->yielder, id_lshift, 1, &v);
             argp->prev_value = argp->prev_elts = Qnil;
         }
     }
     else if (SYMBOL_P(v) && (s = rb_sym2str(v), RSTRING_PTR(s)[0] == '_')) {
-	rb_raise(rb_eRuntimeError, "symbols beginning with an underscore are reserved");
+        rb_raise(rb_eRuntimeError, "symbols beginning with an underscore are reserved");
     }
     else {
         if (NIL_P(argp->prev_value)) {
@@ -3624,7 +3609,7 @@ chunk_ii(RB_BLOCK_CALL_FUNC_ARGLIST(i, _argp))
                 rb_ary_push(argp->prev_elts, i);
             }
             else {
-		s = rb_assoc_new(argp->prev_value, argp->prev_elts);
+                s = rb_assoc_new(argp->prev_value, argp->prev_elts);
                 rb_funcallv(argp->yielder, id_lshift, 1, &s);
                 argp->prev_value = v;
                 argp->prev_elts = rb_ary_new3(1, i);
@@ -3650,8 +3635,8 @@ chunk_i(RB_BLOCK_CALL_FUNC_ARGLIST(yielder, enumerator))
     rb_block_call(enumerable, id_each, 0, 0, chunk_ii, arg);
     memo = MEMO_FOR(struct chunk_arg, arg);
     if (!NIL_P(memo->prev_elts)) {
-	arg = rb_assoc_new(memo->prev_value, memo->prev_elts);
-	rb_funcallv(memo->yielder, id_lshift, 1, &arg);
+        arg = rb_assoc_new(memo->prev_value, memo->prev_elts);
+        rb_funcallv(memo->yielder, id_lshift, 1, &arg);
     }
     return Qnil;
 }
@@ -3832,7 +3817,7 @@ slicebefore_i(RB_BLOCK_CALL_FUNC_ARGLIST(yielder, enumerator))
 /*
  *  call-seq:
  *    slice_before(pattern)       -> enumerator
- *    slice_before {|array| ... } -> enumerator
+ *    slice_before {|elt| ... } -> enumerator
  *
  *  With argument +pattern+, returns an enumerator that uses the pattern
  *  to partition elements into arrays ("slices").
@@ -4077,39 +4062,24 @@ sliceafter_i(RB_BLOCK_CALL_FUNC_ARGLIST(yielder, enumerator))
 
 /*
  *  call-seq:
- *    slice_after(pattern)       -> enumerator
- *    slice_after {|array| ... } -> enumerator
- *
- *  With argument +pattern+, returns an enumerator that uses the pattern
- *  to partition elements into arrays ("slices").
- *  An element ends the current slice if <tt>element === pattern</tt>:
+ *     enum.slice_after(pattern)       -> an_enumerator
+ *     enum.slice_after { |elt| bool } -> an_enumerator
  *
- *    a = %w[foo bar fop for baz fob fog bam foy]
- *    e = a.slice_after(/ba/) # => #<Enumerator: ...>
- *    e.each {|array| p array }
+ *  Creates an enumerator for each chunked elements.
+ *  The ends of chunks are defined by _pattern_ and the block.
  *
- *  Output:
+ *  If <code>_pattern_ === _elt_</code> returns <code>true</code> or the block
+ *  returns <code>true</code> for the element, the element is end of a
+ *  chunk.
  *
- *    ["foo", "bar"]
- *    ["fop", "for", "baz"]
- *    ["fob", "fog", "bam"]
- *    ["foy"]
+ *  The <code>===</code> and _block_ is called from the first element to the last
+ *  element of _enum_.
  *
- *  With a block, returns an enumerator that uses the block
- *  to partition elements into arrays.
- *  An element ends the current slice if its block return is a truthy value:
+ *  The result enumerator yields the chunked elements as an array.
+ *  So +each+ method can be called as follows:
  *
- *    e = (1..20).slice_after {|i| i % 4 == 2 } # => #<Enumerator: ...>
- *    e.each {|array| p array }
- *
- *  Output:
- *
- *    [1, 2]
- *    [3, 4, 5, 6]
- *    [7, 8, 9, 10]
- *    [11, 12, 13, 14]
- *    [15, 16, 17, 18]
- *    [19, 20]
+ *    enum.slice_after(pattern).each { |ary| ... }
+ *    enum.slice_after { |elt| bool }.each { |ary| ... }
  *
  *  Other methods of the Enumerator class and Enumerable module,
  *  such as +map+, etc., are also usable.
@@ -4168,15 +4138,15 @@ slicewhen_ii(RB_BLOCK_CALL_FUNC_ARGLIST(i, _memo))
 
     ENUM_WANT_SVALUE();
 
-    if (memo->prev_elt == Qundef) {
+    if (UNDEF_P(memo->prev_elt)) {
         /* The first element */
         memo->prev_elt = i;
         memo->prev_elts = rb_ary_new3(1, i);
     }
     else {
-	VALUE args[2];
-	args[0] = memo->prev_elt;
-	args[1] = i;
+        VALUE args[2];
+        args[0] = memo->prev_elt;
+        args[1] = i;
         split_p = RTEST(rb_funcallv(memo->pred, id_call, 2, args));
         UPDATE_MEMO;
 
@@ -4205,7 +4175,7 @@ slicewhen_i(RB_BLOCK_CALL_FUNC_ARGLIST(yielder, enumerator))
     VALUE enumerable;
     VALUE arg;
     struct slicewhen_arg *memo =
-	NEW_PARTIAL_MEMO_FOR(struct slicewhen_arg, arg, inverted);
+        NEW_PARTIAL_MEMO_FOR(struct slicewhen_arg, arg, inverted);
 
     enumerable = rb_ivar_get(enumerator, id_slicewhen_enum);
     memo->pred = rb_attr_get(enumerator, id_slicewhen_pred);
@@ -4223,23 +4193,65 @@ slicewhen_i(RB_BLOCK_CALL_FUNC_ARGLIST(yielder, enumerator))
 
 /*
  *  call-seq:
- *    slice_when {|element, next_element| ... } -> enumerator
+ *     enum.slice_when {|elt_before, elt_after| bool } -> an_enumerator
  *
- *  The returned enumerator uses the block
- *  to partition elements into arrays ("slices");
- *  it calls the block with each element and its successor;
- *  begins a new slice if and only if the block returns a truthy value:
+ *  Creates an enumerator for each chunked elements.
+ *  The beginnings of chunks are defined by the block.
  *
- *    a = [0, 1, 2, 4, 5, 6, 8, 9]
- *    e = a.slice_when {|i, j| j != i + 1 }
- *    e.each {|array| p array }
+ *  This method splits each chunk using adjacent elements,
+ *  _elt_before_ and _elt_after_,
+ *  in the receiver enumerator.
+ *  This method split chunks between _elt_before_ and _elt_after_ where
+ *  the block returns <code>true</code>.
  *
- *  Output:
+ *  The block is called the length of the receiver enumerator minus one.
+ *
+ *  The result enumerator yields the chunked elements as an array.
+ *  So +each+ method can be called as follows:
+ *
+ *    enum.slice_when { |elt_before, elt_after| bool }.each { |ary| ... }
+ *
+ *  Other methods of the Enumerator class and Enumerable module,
+ *  such as +to_a+, +map+, etc., are also usable.
  *
- *    [0, 1, 2]
- *    [4, 5, 6]
- *    [8, 9]
+ *  For example, one-by-one increasing subsequence can be chunked as follows:
  *
+ *    a = [1,2,4,9,10,11,12,15,16,19,20,21]
+ *    b = a.slice_when {|i, j| i+1 != j }
+ *    p b.to_a #=> [[1, 2], [4], [9, 10, 11, 12], [15, 16], [19, 20, 21]]
+ *    c = b.map {|a| a.length < 3 ? a : "#{a.first}-#{a.last}" }
+ *    p c #=> [[1, 2], [4], "9-12", [15, 16], "19-21"]
+ *    d = c.join(",")
+ *    p d #=> "1,2,4,9-12,15,16,19-21"
+ *
+ *  Near elements (threshold: 6) in sorted array can be chunked as follows:
+ *
+ *    a = [3, 11, 14, 25, 28, 29, 29, 41, 55, 57]
+ *    p a.slice_when {|i, j| 6 < j - i }.to_a
+ *    #=> [[3], [11, 14], [25, 28, 29, 29], [41], [55, 57]]
+ *
+ *  Increasing (non-decreasing) subsequence can be chunked as follows:
+ *
+ *    a = [0, 9, 2, 2, 3, 2, 7, 5, 9, 5]
+ *    p a.slice_when {|i, j| i > j }.to_a
+ *    #=> [[0, 9], [2, 2, 3], [2, 7], [5, 9], [5]]
+ *
+ *  Adjacent evens and odds can be chunked as follows:
+ *  (Enumerable#chunk is another way to do it.)
+ *
+ *    a = [7, 5, 9, 2, 0, 7, 9, 4, 2, 0]
+ *    p a.slice_when {|i, j| i.even? != j.even? }.to_a
+ *    #=> [[7, 5, 9], [2, 0], [7, 9], [4, 2, 0]]
+ *
+ *  Paragraphs (non-empty lines with trailing empty lines) can be chunked as follows:
+ *  (See Enumerable#chunk to ignore empty lines.)
+ *
+ *    lines = ["foo\n", "bar\n", "\n", "baz\n", "qux\n"]
+ *    p lines.slice_when {|l1, l2| /\A\s*\z/ =~ l1 && /\S/ =~ l2 }.to_a
+ *    #=> [["foo\n", "bar\n", "\n"], ["baz\n", "qux\n"]]
+ *
+ *  Enumerable#chunk_while does the same, except splitting when the block
+ *  returns <code>false</code> instead of <code>true</code>.
  */
 static VALUE
 enum_slice_when(VALUE enumerable)
@@ -4260,27 +4272,52 @@ enum_slice_when(VALUE enumerable)
 
 /*
  *  call-seq:
- *    chunk_while {|element, next_element| ... } -> enumerator
+ *     enum.chunk_while {|elt_before, elt_after| bool } -> an_enumerator
  *
- *  The returned Enumerator uses the block to partition elements
- *  into arrays ("chunks");
- *  it calls the block with each element and its successor;
- *  begins a new chunk if and only if the block returns a truthy value:
+ *  Creates an enumerator for each chunked elements.
+ *  The beginnings of chunks are defined by the block.
  *
- *  Example:
+ *  This method splits each chunk using adjacent elements,
+ *  _elt_before_ and _elt_after_,
+ *  in the receiver enumerator.
+ *  This method split chunks between _elt_before_ and _elt_after_ where
+ *  the block returns <code>false</code>.
  *
- *    a = [1, 2, 4, 9, 10, 11, 12, 15, 16, 19, 20, 21]
- *    e = a.chunk_while {|i, j| j == i + 1 }
- *    e.each {|array| p array }
+ *  The block is called the length of the receiver enumerator minus one.
  *
- *  Output:
+ *  The result enumerator yields the chunked elements as an array.
+ *  So +each+ method can be called as follows:
  *
- *    [1, 2]
- *    [4]
- *    [9, 10, 11, 12]
- *    [15, 16]
- *    [19, 20, 21]
+ *    enum.chunk_while { |elt_before, elt_after| bool }.each { |ary| ... }
+ *
+ *  Other methods of the Enumerator class and Enumerable module,
+ *  such as +to_a+, +map+, etc., are also usable.
+ *
+ *  For example, one-by-one increasing subsequence can be chunked as follows:
+ *
+ *    a = [1,2,4,9,10,11,12,15,16,19,20,21]
+ *    b = a.chunk_while {|i, j| i+1 == j }
+ *    p b.to_a #=> [[1, 2], [4], [9, 10, 11, 12], [15, 16], [19, 20, 21]]
+ *    c = b.map {|a| a.length < 3 ? a : "#{a.first}-#{a.last}" }
+ *    p c #=> [[1, 2], [4], "9-12", [15, 16], "19-21"]
+ *    d = c.join(",")
+ *    p d #=> "1,2,4,9-12,15,16,19-21"
+ *
+ *  Increasing (non-decreasing) subsequence can be chunked as follows:
+ *
+ *    a = [0, 9, 2, 2, 3, 2, 7, 5, 9, 5]
+ *    p a.chunk_while {|i, j| i <= j }.to_a
+ *    #=> [[0, 9], [2, 2, 3], [2, 7], [5, 9], [5]]
+ *
+ *  Adjacent evens and odds can be chunked as follows:
+ *  (Enumerable#chunk is another way to do it.)
+ *
+ *    a = [7, 5, 9, 2, 0, 7, 9, 4, 2, 0]
+ *    p a.chunk_while {|i, j| i.even? == j.even? }.to_a
+ *    #=> [[7, 5, 9], [2, 0], [7, 9], [4, 2, 0]]
  *
+ *  Enumerable#slice_when does the same, except splitting when the block
+ *  returns <code>true</code> instead of <code>false</code>.
  */
 static VALUE
 enum_chunk_while(VALUE enumerable)
@@ -4341,7 +4378,7 @@ sum_iter_bignum(VALUE i, struct enum_sum_memo *memo)
 static void
 sum_iter_rational(VALUE i, struct enum_sum_memo *memo)
 {
-    if (memo->r == Qundef) {
+    if (UNDEF_P(memo->r)) {
         memo->r = i;
     }
     else {
@@ -4422,7 +4459,7 @@ sum_iter(VALUE i, struct enum_sum_memo *memo)
     }
     else switch (TYPE(memo->v)) {
       default:      sum_iter_some_value(i, memo);    return;
-      case T_FLOAT: sum_iter_Kahan_Babuska(i, memo); return;
+      case T_FLOAT:
       case T_FIXNUM:
       case T_BIGNUM:
       case T_RATIONAL:
@@ -4562,7 +4599,7 @@ enum_sum(int argc, VALUE* argv, VALUE obj)
     else {
         if (memo.n != 0)
             memo.v = rb_fix_plus(LONG2FIX(memo.n), memo.v);
-        if (memo.r != Qundef) {
+        if (!UNDEF_P(memo.r)) {
             memo.v = rb_rational_plus(memo.r, memo.v);
         }
         return memo.v;
@@ -4611,7 +4648,7 @@ enum_uniq(VALUE obj)
 {
     VALUE hash, ret;
     rb_block_call_func *const func =
-	rb_block_given_p() ? uniq_iter : uniq_func;
+        rb_block_given_p() ? uniq_iter : uniq_func;
 
     hash = rb_obj_hide(rb_hash_new());
     rb_block_call(obj, id_each, 0, 0, func, hash);
@@ -4754,7 +4791,7 @@ enum_compact(VALUE obj)
  * - #grep_v: Returns elements selected by a given object
  *   or objects returned by a given block.
  * - #reduce, #inject: Returns the object formed by combining all elements.
- * - #sum: Returns the sum of the elements, using method +++.
+ * - #sum: Returns the sum of the elements, using method <tt>+</tt>.
  * - #zip: Combines each element with elements from other enumerables;
  *   returns the n-tuples or calls the block with each.
  * - #cycle: Calls the block with each element, cycling repeatedly.
diff --git a/enumerator.c b/enumerator.c
index be469ee38b..d587b63d32 100644
--- a/enumerator.c
+++ b/enumerator.c
@@ -20,6 +20,7 @@
 
 #include "id.h"
 #include "internal.h"
+#include "internal/class.h"
 #include "internal/enumerator.h"
 #include "internal/error.h"
 #include "internal/hash.h"
@@ -72,6 +73,8 @@
  *   puts %w[foo bar baz].map.with_index { |w, i| "#{i}:#{w}" }
  *   # => ["0:foo", "1:bar", "2:baz"]
  *
+ *  == External Iteration
+ *
  * An Enumerator can also be used as an external iterator.
  * For example, Enumerator#next returns the next value of the iterator
  * or raises StopIteration if the Enumerator is at the end.
@@ -82,15 +85,44 @@
  *   puts e.next   # => 3
  *   puts e.next   # raises StopIteration
  *
- * Note that enumeration sequence by +next+, +next_values+, +peek+ and
- * +peek_values+ do not affect other non-external
- * enumeration methods, unless the underlying iteration method itself has
- * side-effect, e.g. IO#each_line.
+ * +next+, +next_values+, +peek+ and +peek_values+ are the only methods
+ * which use external iteration (and Array#zip(Enumerable-not-Array) which uses +next+).
+ *
+ * These methods do not affect other internal enumeration methods,
+ * unless the underlying iteration method itself has side-effect, e.g. IO#each_line.
+ *
+ * External iteration differs *significantly* from internal iteration
+ * due to using a Fiber:
+ *  - The Fiber adds some overhead compared to internal enumeration.
+ *  - The stacktrace will only include the stack from the Enumerator, not above.
+ *  - Fiber-local variables are *not* inherited inside the Enumerator Fiber,
+ *    which instead starts with no Fiber-local variables.
+ *  - Fiber storage variables *are* inherited and are designed
+ *    to handle Enumerator Fibers. Assigning to a Fiber storage variable
+ *    only affects the current Fiber, so if you want to change state
+ *    in the caller Fiber of the Enumerator Fiber, you need to use an
+ *    extra indirection (e.g., use some object in the Fiber storage
+ *    variable and mutate some ivar of it).
+ *
+ * Concretely:
+ *   Thread.current[:fiber_local] = 1
+ *   Fiber[:storage_var] = 1
+ *   e = Enumerator.new do |y|
+ *     p Thread.current[:fiber_local] # for external iteration: nil, for internal iteration: 1
+ *     p Fiber[:storage_var] # => 1, inherited
+ *     Fiber[:storage_var] += 1
+ *     y << 42
+ *   end
+ *
+ *   p e.next # => 42
+ *   p Fiber[:storage_var] # => 1 (it ran in a different Fiber)
  *
- * Moreover, implementation typically uses fibers so performance could be
- * slower and exception stacktraces different than expected.
+ *   e.each { p _1 }
+ *   p Fiber[:storage_var] # => 2 (it ran in the same Fiber/"stack" as the current Fiber)
  *
- * You can use this to implement an internal iterator as follows:
+ *  == Convert External Iteration to Internal Iteration
+ *
+ * You can use an external iterator to implement an internal iterator as follows:
  *
  *   def ext_each(e)
  *     while true
@@ -125,14 +157,17 @@
  */
 VALUE rb_cEnumerator;
 static VALUE rb_cLazy;
-static ID id_rewind, id_new, id_to_enum;
+static ID id_rewind, id_new, id_to_enum, id_each_entry;
 static ID id_next, id_result, id_receiver, id_arguments, id_memo, id_method, id_force;
 static ID id_begin, id_end, id_step, id_exclude_end;
 static VALUE sym_each, sym_cycle, sym_yield;
 
 static VALUE lazy_use_super_method;
 
+extern ID ruby_static_id_cause;
+
 #define id_call idCall
+#define id_cause ruby_static_id_cause
 #define id_each idEach
 #define id_eqq idEqq
 #define id_initialize idInitialize
@@ -173,9 +208,11 @@ struct producer {
 
 typedef struct MEMO *lazyenum_proc_func(VALUE, struct MEMO *, VALUE, long);
 typedef VALUE lazyenum_size_func(VALUE, VALUE);
+typedef int lazyenum_precheck_func(VALUE proc_entry);
 typedef struct {
     lazyenum_proc_func *proc;
     lazyenum_size_func *size;
+    lazyenum_precheck_func *precheck;
 } lazyenum_funcs;
 
 struct proc_entry {
@@ -194,6 +231,12 @@ struct enum_chain {
     long pos;
 };
 
+static VALUE rb_cEnumProduct;
+
+struct enum_product {
+    VALUE enums;
+};
+
 VALUE rb_cArithSeq;
 
 /*
@@ -240,9 +283,9 @@ enumerator_memsize(const void *p)
 static const rb_data_type_t enumerator_data_type = {
     "enumerator",
     {
-	enumerator_mark,
-	enumerator_free,
-	enumerator_memsize,
+        enumerator_mark,
+        enumerator_free,
+        enumerator_memsize,
         enumerator_compact,
     },
     0, 0, RUBY_TYPED_FREE_IMMEDIATELY
@@ -254,8 +297,8 @@ enumerator_ptr(VALUE obj)
     struct enumerator *ptr;
 
     TypedData_Get_Struct(obj, struct enumerator, &enumerator_data_type, ptr);
-    if (!ptr || ptr->obj == Qundef) {
-	rb_raise(rb_eArgError, "uninitialized enumerator");
+    if (!ptr || UNDEF_P(ptr->obj)) {
+        rb_raise(rb_eArgError, "uninitialized enumerator");
     }
     return ptr;
 }
@@ -287,9 +330,9 @@ proc_entry_memsize(const void *p)
 static const rb_data_type_t proc_entry_data_type = {
     "proc_entry",
     {
-	proc_entry_mark,
-	proc_entry_free,
-	proc_entry_memsize,
+        proc_entry_mark,
+        proc_entry_free,
+        proc_entry_memsize,
         proc_entry_compact,
     },
 };
@@ -371,12 +414,12 @@ obj_to_enum(int argc, VALUE *argv, VALUE obj)
     VALUE enumerator, meth = sym_each;
 
     if (argc > 0) {
-	--argc;
-	meth = *argv++;
+        --argc;
+        meth = *argv++;
     }
     enumerator = rb_enumeratorize_with_size(obj, meth, argc, argv, 0);
     if (rb_block_given_p()) {
-	enumerator_ptr(enumerator)->size = rb_block_proc();
+        enumerator_ptr(enumerator)->size = rb_block_proc();
     }
     return enumerator;
 }
@@ -402,7 +445,7 @@ enumerator_init(VALUE enum_obj, VALUE obj, VALUE meth, int argc, const VALUE *ar
     TypedData_Get_Struct(enum_obj, struct enumerator, &enumerator_data_type, ptr);
 
     if (!ptr) {
-	rb_raise(rb_eArgError, "unallocated enumerator");
+        rb_raise(rb_eArgError, "unallocated enumerator");
     }
 
     ptr->obj  = obj;
@@ -482,14 +525,14 @@ enumerator_init_copy(VALUE obj, VALUE orig)
     if (!OBJ_INIT_COPY(obj, orig)) return obj;
     ptr0 = enumerator_ptr(orig);
     if (ptr0->fib) {
-	/* Fibers cannot be copied */
-	rb_raise(rb_eTypeError, "can't copy execution context");
+        /* Fibers cannot be copied */
+        rb_raise(rb_eTypeError, "can't copy execution context");
     }
 
     TypedData_Get_Struct(obj, struct enumerator, &enumerator_data_type, ptr1);
 
     if (!ptr1) {
-	rb_raise(rb_eArgError, "unallocated enumerator");
+        rb_raise(rb_eArgError, "unallocated enumerator");
     }
 
     ptr1->obj  = ptr0->obj;
@@ -513,8 +556,8 @@ rb_enumeratorize(VALUE obj, VALUE meth, int argc, const VALUE *argv)
     return rb_enumeratorize_with_size(obj, meth, argc, argv, 0);
 }
 
-static VALUE
-lazy_to_enum_i(VALUE self, VALUE meth, int argc, const VALUE *argv, rb_enumerator_size_func *size_fn, int kw_splat);
+static VALUE lazy_to_enum_i(VALUE self, VALUE meth, int argc, const VALUE *argv, rb_enumerator_size_func *size_fn, int kw_splat);
+static int lazy_precheck(VALUE procs);
 
 VALUE
 rb_enumeratorize_with_size_kw(VALUE obj, VALUE meth, int argc, const VALUE *argv, rb_enumerator_size_func *size_fn, int kw_splat)
@@ -547,8 +590,8 @@ enumerator_block_call(VALUE obj, rb_block_call_func *func, VALUE arg)
     ID meth = e->meth;
 
     if (e->args) {
-	argc = RARRAY_LENINT(e->args);
-	argv = RARRAY_CONST_PTR(e->args);
+        argc = RARRAY_LENINT(e->args);
+        argv = RARRAY_CONST_PTR(e->args);
     }
     return rb_block_call_kw(e->obj, meth, argc, argv, func, arg, e->kw_splat);
 }
@@ -592,25 +635,29 @@ enumerator_block_call(VALUE obj, rb_block_call_func *func, VALUE arg)
 static VALUE
 enumerator_each(int argc, VALUE *argv, VALUE obj)
 {
+    struct enumerator *e = enumerator_ptr(obj);
+
     if (argc > 0) {
-	struct enumerator *e = enumerator_ptr(obj = rb_obj_dup(obj));
-	VALUE args = e->args;
-	if (args) {
+        VALUE args = (e = enumerator_ptr(obj = rb_obj_dup(obj)))->args;
+        if (args) {
 #if SIZEOF_INT < SIZEOF_LONG
-	    /* check int range overflow */
-	    rb_long2int(RARRAY_LEN(args) + argc);
+            /* check int range overflow */
+            rb_long2int(RARRAY_LEN(args) + argc);
 #endif
-	    args = rb_ary_dup(args);
-	    rb_ary_cat(args, argv, argc);
-	}
-	else {
-	    args = rb_ary_new4(argc, argv);
-	}
-	e->args = args;
+            args = rb_ary_dup(args);
+            rb_ary_cat(args, argv, argc);
+        }
+        else {
+            args = rb_ary_new4(argc, argv);
+        }
+        e->args = args;
         e->size = Qnil;
         e->size_fn = 0;
     }
     if (!rb_block_given_p()) return obj;
+
+    if (!lazy_precheck(e->procs)) return Qnil;
+
     return enumerator_block_call(obj, 0, obj);
 }
 
@@ -622,7 +669,7 @@ enumerator_with_index_i(RB_BLOCK_CALL_FUNC_ARGLIST(val, m))
     MEMO_V1_SET(memo, rb_int_succ(idx));
 
     if (argc <= 1)
-	return rb_yield_values(2, val, idx);
+        return rb_yield_values(2, val, idx);
 
     return rb_yield_values(2, rb_ary_new4(argc, argv), idx);
 }
@@ -679,7 +726,7 @@ static VALUE
 enumerator_with_object_i(RB_BLOCK_CALL_FUNC_ARGLIST(val, memo))
 {
     if (argc <= 1)
-	return rb_yield_values(2, val, memo);
+        return rb_yield_values(2, val, memo);
 
     return rb_yield_values(2, rb_ary_new4(argc, argv), memo);
 }
@@ -729,7 +776,7 @@ next_ii(RB_BLOCK_CALL_FUNC_ARGLIST(i, obj))
     VALUE feedvalue = Qnil;
     VALUE args = rb_ary_new4(argc, argv);
     rb_fiber_yield(1, &args);
-    if (e->feedvalue != Qundef) {
+    if (!UNDEF_P(e->feedvalue)) {
         feedvalue = e->feedvalue;
         e->feedvalue = Qundef;
     }
@@ -763,22 +810,30 @@ get_next_values(VALUE obj, struct enumerator *e)
 {
     VALUE curr, vs;
 
-    if (e->stop_exc)
-	rb_exc_raise(e->stop_exc);
+    if (e->stop_exc) {
+        VALUE exc = e->stop_exc;
+        VALUE result = rb_attr_get(exc, id_result);
+        VALUE mesg = rb_attr_get(exc, idMesg);
+        if (!NIL_P(mesg)) mesg = rb_str_dup(mesg);
+        VALUE stop_exc = rb_exc_new_str(rb_eStopIteration, mesg);
+        rb_ivar_set(stop_exc, id_cause, exc);
+        rb_ivar_set(stop_exc, id_result, result);
+        rb_exc_raise(stop_exc);
+    }
 
     curr = rb_fiber_current();
 
     if (!e->fib || !rb_fiber_alive_p(e->fib)) {
-	next_init(obj, e);
+        next_init(obj, e);
     }
 
     vs = rb_fiber_resume(e->fib, 1, &curr);
     if (e->stop_exc) {
-	e->fib = 0;
-	e->dst = Qnil;
-	e->lookahead = Qundef;
-	e->feedvalue = Qundef;
-	rb_exc_raise(e->stop_exc);
+        e->fib = 0;
+        e->dst = Qnil;
+        e->lookahead = Qundef;
+        e->feedvalue = Qundef;
+        rb_exc_raise(e->stop_exc);
     }
     return vs;
 }
@@ -834,7 +889,7 @@ enumerator_next_values(VALUE obj)
     struct enumerator *e = enumerator_ptr(obj);
     VALUE vs;
 
-    if (e->lookahead != Qundef) {
+    if (!UNDEF_P(e->lookahead)) {
         vs = e->lookahead;
         e->lookahead = Qundef;
         return vs;
@@ -895,7 +950,7 @@ enumerator_peek_values(VALUE obj)
 {
     struct enumerator *e = enumerator_ptr(obj);
 
-    if (e->lookahead == Qundef) {
+    if (UNDEF_P(e->lookahead)) {
         e->lookahead = get_next_values(obj, e);
     }
     return e->lookahead;
@@ -1019,8 +1074,8 @@ enumerator_feed(VALUE obj, VALUE v)
 {
     struct enumerator *e = enumerator_ptr(obj);
 
-    if (e->feedvalue != Qundef) {
-	rb_raise(rb_eTypeError, "feed value already set");
+    if (!UNDEF_P(e->feedvalue)) {
+        rb_raise(rb_eTypeError, "feed value already set");
     }
     e->feedvalue = v;
 
@@ -1064,37 +1119,37 @@ inspect_enumerator(VALUE obj, VALUE dummy, int recur)
 
     cname = rb_obj_class(obj);
 
-    if (!e || e->obj == Qundef) {
-	return rb_sprintf("#<%"PRIsVALUE": uninitialized>", rb_class_path(cname));
+    if (!e || UNDEF_P(e->obj)) {
+        return rb_sprintf("#<%"PRIsVALUE": uninitialized>", rb_class_path(cname));
     }
 
     if (recur) {
-	str = rb_sprintf("#<%"PRIsVALUE": ...>", rb_class_path(cname));
-	return str;
+        str = rb_sprintf("#<%"PRIsVALUE": ...>", rb_class_path(cname));
+        return str;
     }
 
     if (e->procs) {
-	long i;
-
-	eobj = generator_ptr(e->obj)->obj;
-	/* In case procs chained enumerator traversing all proc entries manually */
-	if (rb_obj_class(eobj) == cname) {
-	    str = rb_inspect(eobj);
-	}
-	else {
-	    str = rb_sprintf("#<%"PRIsVALUE": %+"PRIsVALUE">", rb_class_path(cname), eobj);
-	}
-	for (i = 0; i < RARRAY_LEN(e->procs); i++) {
-	    str = rb_sprintf("#<%"PRIsVALUE": %"PRIsVALUE, cname, str);
-	    append_method(RARRAY_AREF(e->procs, i), str, e->meth, e->args);
-	    rb_str_buf_cat2(str, ">");
-	}
-	return str;
+        long i;
+
+        eobj = generator_ptr(e->obj)->obj;
+        /* In case procs chained enumerator traversing all proc entries manually */
+        if (rb_obj_class(eobj) == cname) {
+            str = rb_inspect(eobj);
+        }
+        else {
+            str = rb_sprintf("#<%"PRIsVALUE": %+"PRIsVALUE">", rb_class_path(cname), eobj);
+        }
+        for (i = 0; i < RARRAY_LEN(e->procs); i++) {
+            str = rb_sprintf("#<%"PRIsVALUE": %"PRIsVALUE, cname, str);
+            append_method(RARRAY_AREF(e->procs, i), str, e->meth, e->args);
+            rb_str_buf_cat2(str, ">");
+        }
+        return str;
     }
 
     eobj = rb_attr_get(obj, id_receiver);
     if (NIL_P(eobj)) {
-	eobj = e->obj;
+        eobj = e->obj;
     }
 
     /* (1..100).each_cons(2) => "#<Enumerator: 1..100:each_cons(2)>" */
@@ -1129,48 +1184,48 @@ append_method(VALUE obj, VALUE str, ID default_method, VALUE default_args)
 
     method = rb_attr_get(obj, id_method);
     if (method != Qfalse) {
-	if (!NIL_P(method)) {
-	    Check_Type(method, T_SYMBOL);
-	    method = rb_sym2str(method);
-	}
-	else {
-	    method = rb_id2str(default_method);
-	}
-	rb_str_buf_cat2(str, ":");
-	rb_str_buf_append(str, method);
+        if (!NIL_P(method)) {
+            Check_Type(method, T_SYMBOL);
+            method = rb_sym2str(method);
+        }
+        else {
+            method = rb_id2str(default_method);
+        }
+        rb_str_buf_cat2(str, ":");
+        rb_str_buf_append(str, method);
     }
 
     eargs = rb_attr_get(obj, id_arguments);
     if (NIL_P(eargs)) {
-	eargs = default_args;
+        eargs = default_args;
     }
     if (eargs != Qfalse) {
-	long   argc = RARRAY_LEN(eargs);
-	const VALUE *argv = RARRAY_CONST_PTR(eargs); /* WB: no new reference */
+        long   argc = RARRAY_LEN(eargs);
+        const VALUE *argv = RARRAY_CONST_PTR(eargs); /* WB: no new reference */
 
-	if (argc > 0) {
-	    VALUE kwds = Qnil;
+        if (argc > 0) {
+            VALUE kwds = Qnil;
 
-	    rb_str_buf_cat2(str, "(");
+            rb_str_buf_cat2(str, "(");
 
             if (RB_TYPE_P(argv[argc-1], T_HASH) && !RHASH_EMPTY_P(argv[argc-1])) {
-		int all_key = TRUE;
-		rb_hash_foreach(argv[argc-1], key_symbol_p, (VALUE)&all_key);
-		if (all_key) kwds = argv[--argc];
-	    }
+                int all_key = TRUE;
+                rb_hash_foreach(argv[argc-1], key_symbol_p, (VALUE)&all_key);
+                if (all_key) kwds = argv[--argc];
+            }
 
-	    while (argc--) {
-		VALUE arg = *argv++;
+            while (argc--) {
+                VALUE arg = *argv++;
 
-		rb_str_append(str, rb_inspect(arg));
-		rb_str_buf_cat2(str, ", ");
-	    }
-	    if (!NIL_P(kwds)) {
-		rb_hash_foreach(kwds, kwd_append, str);
-	    }
-	    rb_str_set_len(str, RSTRING_LEN(str)-2);
-	    rb_str_buf_cat2(str, ")");
-	}
+                rb_str_append(str, rb_inspect(arg));
+                rb_str_buf_cat2(str, ", ");
+            }
+            if (!NIL_P(kwds)) {
+                rb_hash_foreach(kwds, kwd_append, str);
+            }
+            rb_str_set_len(str, RSTRING_LEN(str)-2);
+            rb_str_buf_cat2(str, ")");
+        }
     }
 
     return str;
@@ -1209,31 +1264,31 @@ enumerator_size(VALUE obj)
     VALUE size;
 
     if (e->procs) {
-	struct generator *g = generator_ptr(e->obj);
-	VALUE receiver = rb_check_funcall(g->obj, id_size, 0, 0);
-	long i = 0;
-
-	for (i = 0; i < RARRAY_LEN(e->procs); i++) {
-	    VALUE proc = RARRAY_AREF(e->procs, i);
-	    struct proc_entry *entry = proc_entry_ptr(proc);
-	    lazyenum_size_func *size_fn = entry->fn->size;
-	    if (!size_fn) {
-		return Qnil;
-	    }
-	    receiver = (*size_fn)(proc, receiver);
-	}
-	return receiver;
+        struct generator *g = generator_ptr(e->obj);
+        VALUE receiver = rb_check_funcall(g->obj, id_size, 0, 0);
+        long i = 0;
+
+        for (i = 0; i < RARRAY_LEN(e->procs); i++) {
+            VALUE proc = RARRAY_AREF(e->procs, i);
+            struct proc_entry *entry = proc_entry_ptr(proc);
+            lazyenum_size_func *size_fn = entry->fn->size;
+            if (!size_fn) {
+                return Qnil;
+            }
+            receiver = (*size_fn)(proc, receiver);
+        }
+        return receiver;
     }
 
     if (e->size_fn) {
-	return (*e->size_fn)(e->obj, e->args, obj);
+        return (*e->size_fn)(e->obj, e->args, obj);
     }
     if (e->args) {
-	argc = (int)RARRAY_LEN(e->args);
-	argv = RARRAY_CONST_PTR(e->args);
+        argc = (int)RARRAY_LEN(e->args);
+        argv = RARRAY_CONST_PTR(e->args);
     }
     size = rb_check_funcall_kw(e->size, id_call, argc, argv, e->kw_splat);
-    if (size != Qundef) return size;
+    if (!UNDEF_P(size)) return size;
     return e->size;
 }
 
@@ -1265,9 +1320,9 @@ yielder_memsize(const void *p)
 static const rb_data_type_t yielder_data_type = {
     "yielder",
     {
-	yielder_mark,
-	yielder_free,
-	yielder_memsize,
+        yielder_mark,
+        yielder_free,
+        yielder_memsize,
         yielder_compact,
     },
     0, 0, RUBY_TYPED_FREE_IMMEDIATELY
@@ -1279,8 +1334,8 @@ yielder_ptr(VALUE obj)
     struct yielder *ptr;
 
     TypedData_Get_Struct(obj, struct yielder, &yielder_data_type, ptr);
-    if (!ptr || ptr->proc == Qundef) {
-	rb_raise(rb_eArgError, "uninitialized yielder");
+    if (!ptr || UNDEF_P(ptr->proc)) {
+        rb_raise(rb_eArgError, "uninitialized yielder");
     }
     return ptr;
 }
@@ -1306,7 +1361,7 @@ yielder_init(VALUE obj, VALUE proc)
     TypedData_Get_Struct(obj, struct yielder, &yielder_data_type, ptr);
 
     if (!ptr) {
-	rb_raise(rb_eArgError, "unallocated yielder");
+        rb_raise(rb_eArgError, "unallocated yielder");
     }
 
     ptr->proc = proc;
@@ -1405,9 +1460,9 @@ generator_memsize(const void *p)
 static const rb_data_type_t generator_data_type = {
     "generator",
     {
-	generator_mark,
-	generator_free,
-	generator_memsize,
+        generator_mark,
+        generator_free,
+        generator_memsize,
         generator_compact,
     },
     0, 0, RUBY_TYPED_FREE_IMMEDIATELY
@@ -1419,8 +1474,8 @@ generator_ptr(VALUE obj)
     struct generator *ptr;
 
     TypedData_Get_Struct(obj, struct generator, &generator_data_type, ptr);
-    if (!ptr || ptr->proc == Qundef) {
-	rb_raise(rb_eArgError, "uninitialized generator");
+    if (!ptr || UNDEF_P(ptr->proc)) {
+        rb_raise(rb_eArgError, "uninitialized generator");
     }
     return ptr;
 }
@@ -1447,7 +1502,7 @@ generator_init(VALUE obj, VALUE proc)
     TypedData_Get_Struct(obj, struct generator, &generator_data_type, ptr);
 
     if (!ptr) {
-	rb_raise(rb_eArgError, "unallocated generator");
+        rb_raise(rb_eArgError, "unallocated generator");
     }
 
     ptr->proc = proc;
@@ -1462,21 +1517,21 @@ generator_initialize(int argc, VALUE *argv, VALUE obj)
     VALUE proc;
 
     if (argc == 0) {
-	rb_need_block();
+        rb_need_block();
 
-	proc = rb_block_proc();
+        proc = rb_block_proc();
     }
     else {
-	rb_scan_args(argc, argv, "1", &proc);
+        rb_scan_args(argc, argv, "1", &proc);
 
-	if (!rb_obj_is_proc(proc))
-	    rb_raise(rb_eTypeError,
-		     "wrong argument type %"PRIsVALUE" (expected Proc)",
-		     rb_obj_class(proc));
+        if (!rb_obj_is_proc(proc))
+            rb_raise(rb_eTypeError,
+                     "wrong argument type %"PRIsVALUE" (expected Proc)",
+                     rb_obj_class(proc));
 
-	if (rb_block_given_p()) {
-	    rb_warn("given block not used");
-	}
+        if (rb_block_given_p()) {
+            rb_warn("given block not used");
+        }
     }
 
     return generator_init(obj, proc);
@@ -1495,7 +1550,7 @@ generator_init_copy(VALUE obj, VALUE orig)
     TypedData_Get_Struct(obj, struct generator, &generator_data_type, ptr1);
 
     if (!ptr1) {
-	rb_raise(rb_eArgError, "unallocated generator");
+        rb_raise(rb_eArgError, "unallocated generator");
     }
 
     ptr1->proc = ptr0->proc;
@@ -1512,7 +1567,7 @@ generator_each(int argc, VALUE *argv, VALUE obj)
 
     rb_ary_push(args, yielder_new());
     if (argc > 0) {
-	rb_ary_cat(args, argv, argc);
+        rb_ary_cat(args, argv, argc);
     }
 
     return rb_proc_call_kw(ptr->proc, args, RB_PASS_CALLED_KEYWORDS);
@@ -1523,7 +1578,7 @@ static VALUE
 enum_size(VALUE self)
 {
     VALUE r = rb_check_funcall(self, id_size, 0, 0);
-    return (r == Qundef) ? Qnil : r;
+    return UNDEF_P(r) ? Qnil : r;
 }
 
 static VALUE
@@ -1539,24 +1594,24 @@ lazy_init_iterator(RB_BLOCK_CALL_FUNC_ARGLIST(val, m))
 {
     VALUE result;
     if (argc == 1) {
-	VALUE args[2];
-	args[0] = m;
-	args[1] = val;
-	result = rb_yield_values2(2, args);
+        VALUE args[2];
+        args[0] = m;
+        args[1] = val;
+        result = rb_yield_values2(2, args);
     }
     else {
-	VALUE args;
-	int len = rb_long2int((long)argc + 1);
-	VALUE *nargv = ALLOCV_N(VALUE, args, len);
-
-	nargv[0] = m;
-	if (argc > 0) {
-	    MEMCPY(nargv + 1, argv, VALUE, argc);
-	}
-	result = rb_yield_values2(len, nargv);
-	ALLOCV_END(args);
-    }
-    if (result == Qundef) rb_iter_break();
+        VALUE args;
+        int len = rb_long2int((long)argc + 1);
+        VALUE *nargv = ALLOCV_N(VALUE, args, len);
+
+        nargv[0] = m;
+        if (argc > 0) {
+            MEMCPY(nargv + 1, argv, VALUE, argc);
+        }
+        result = rb_yield_values2(len, nargv);
+        ALLOCV_END(args);
+    }
+    if (UNDEF_P(result)) rb_iter_break();
     return Qnil;
 }
 
@@ -1590,7 +1645,7 @@ lazy_init_yielder(RB_BLOCK_CALL_FUNC_ARGLIST(_, m))
     struct MEMO *result;
 
     result = MEMO_NEW(m, rb_enum_values_pack(argc, argv),
-		      argc > 1 ? LAZY_MEMO_PACKED : 0);
+                      argc > 1 ? LAZY_MEMO_PACKED : 0);
     return lazy_yielder_result(result, yielder, procs_array, memos, 0);
 }
 
@@ -1615,19 +1670,19 @@ lazy_yielder_result(struct MEMO *result, VALUE yielder, VALUE procs_array, VALUE
     int cont = 1;
 
     for (; i < RARRAY_LEN(procs_array); i++) {
-	VALUE proc = RARRAY_AREF(procs_array, i);
-	struct proc_entry *entry = proc_entry_ptr(proc);
-	if (!(*entry->fn->proc)(proc, result, memos, i)) {
-	    cont = 0;
-	    break;
-	}
+        VALUE proc = RARRAY_AREF(procs_array, i);
+        struct proc_entry *entry = proc_entry_ptr(proc);
+        if (!(*entry->fn->proc)(proc, result, memos, i)) {
+            cont = 0;
+            break;
+        }
     }
 
     if (cont) {
-	rb_funcall2(yielder, idLTLT, 1, &(result->memo_value));
+        rb_funcall2(yielder, idLTLT, 1, &(result->memo_value));
     }
     if (LAZY_MEMO_BREAK_P(result)) {
-	rb_iter_break();
+        rb_iter_break();
     }
     return result->memo_value;
 }
@@ -1639,7 +1694,7 @@ lazy_init_block(RB_BLOCK_CALL_FUNC_ARGLIST(val, m))
 
     rb_ivar_set(val, id_memo, rb_ary_new2(RARRAY_LEN(procs)));
     rb_block_call(RARRAY_AREF(m, 0), id_each, 0, 0,
-		  lazy_init_yielder, rb_ary_new3(2, val, procs));
+                  lazy_init_yielder, rb_ary_new3(2, val, procs));
     return Qnil;
 }
 
@@ -1652,17 +1707,17 @@ lazy_generator_init(VALUE enumerator, VALUE procs)
     struct enumerator *e = enumerator_ptr(enumerator);
 
     if (RARRAY_LEN(procs) > 0) {
-	struct generator *old_gen_ptr = generator_ptr(e->obj);
-	obj = old_gen_ptr->obj;
+        struct generator *old_gen_ptr = generator_ptr(e->obj);
+        obj = old_gen_ptr->obj;
     }
     else {
-	obj = enumerator;
+        obj = enumerator;
     }
 
     generator = generator_allocate(rb_cGenerator);
 
     rb_block_call(generator, id_initialize, 0, 0,
-		  lazy_init_block, rb_ary_new3(2, obj, procs));
+                  lazy_init_block, rb_ary_new3(2, obj, procs));
 
     gen_ptr = generator_ptr(generator);
     gen_ptr->obj = obj;
@@ -1670,6 +1725,22 @@ lazy_generator_init(VALUE enumerator, VALUE procs)
     return generator;
 }
 
+static int
+lazy_precheck(VALUE procs)
+{
+    if (RTEST(procs)) {
+        long num_procs = RARRAY_LEN(procs), i = num_procs;
+        while (i-- > 0) {
+            VALUE proc = RARRAY_AREF(procs, i);
+            struct proc_entry *entry = proc_entry_ptr(proc);
+            lazyenum_precheck_func *precheck = entry->fn->precheck;
+            if (precheck && !precheck(proc)) return FALSE;
+        }
+    }
+
+    return TRUE;
+}
+
 /*
  * Document-class: Enumerator::Lazy
  *
@@ -1767,11 +1838,11 @@ lazy_initialize(int argc, VALUE *argv, VALUE self)
 
     rb_check_arity(argc, 1, 2);
     if (!rb_block_given_p()) {
-	rb_raise(rb_eArgError, "tried to call lazy new without a block");
+        rb_raise(rb_eArgError, "tried to call lazy new without a block");
     }
     obj = argv[0];
     if (argc > 1) {
-	size = argv[1];
+        size = argv[1];
     }
     generator = generator_allocate(rb_cGenerator);
     rb_block_call(generator, id_initialize, 0, 0, lazy_init_block_i, obj);
@@ -1790,7 +1861,8 @@ lazy_initialize(int argc, VALUE *argv, VALUE self)
  * Expands +lazy+ enumerator to an array.
  * See Enumerable#to_a.
  */
-static VALUE lazy_to_a(VALUE self)
+static VALUE
+lazy_to_a(VALUE self)
 {
 }
 #endif
@@ -1801,11 +1873,11 @@ lazy_set_args(VALUE lazy, VALUE args)
     ID id = rb_frame_this_func();
     rb_ivar_set(lazy, id_method, ID2SYM(id));
     if (NIL_P(args)) {
-	/* Qfalse indicates that the arguments are empty */
-	rb_ivar_set(lazy, id_arguments, Qfalse);
+        /* Qfalse indicates that the arguments are empty */
+        rb_ivar_set(lazy, id_arguments, Qfalse);
     }
     else {
-	rb_ivar_set(lazy, id_arguments, args);
+        rb_ivar_set(lazy, id_arguments, args);
     }
 }
 
@@ -1822,7 +1894,7 @@ lazy_set_method(VALUE lazy, VALUE args, rb_enumerator_size_func *size_fn)
 
 static VALUE
 lazy_add_method(VALUE obj, int argc, VALUE *argv, VALUE args, VALUE memo,
-		const lazyenum_funcs *fn)
+                const lazyenum_funcs *fn)
 {
     struct enumerator *new_e;
     VALUE new_obj;
@@ -1831,9 +1903,9 @@ lazy_add_method(VALUE obj, int argc, VALUE *argv, VALUE args, VALUE memo,
     struct enumerator *e = enumerator_ptr(obj);
     struct proc_entry *entry;
     VALUE entry_obj = TypedData_Make_Struct(rb_cObject, struct proc_entry,
-					    &proc_entry_data_type, entry);
+                                            &proc_entry_data_type, entry);
     if (rb_block_given_p()) {
-	entry->proc = rb_block_proc();
+        entry->proc = rb_block_proc();
     }
     entry->fn = fn;
     entry->memo = args;
@@ -1850,11 +1922,11 @@ lazy_add_method(VALUE obj, int argc, VALUE *argv, VALUE args, VALUE memo,
     new_e->procs = new_procs;
 
     if (argc > 0) {
-	new_e->meth = rb_to_id(*argv++);
-	--argc;
+        new_e->meth = rb_to_id(*argv++);
+        --argc;
     }
     else {
-	new_e->meth = id_each;
+        new_e->meth = id_each;
     }
     new_e->args = rb_ary_new4(argc, argv);
     return new_obj;
@@ -1934,15 +2006,15 @@ lazy_to_enum(int argc, VALUE *argv, VALUE self)
     VALUE lazy, meth = sym_each, super_meth;
 
     if (argc > 0) {
-	--argc;
-	meth = *argv++;
+        --argc;
+        meth = *argv++;
     }
     if (RTEST((super_meth = rb_hash_aref(lazy_use_super_method, meth)))) {
         meth = super_meth;
     }
     lazy = lazy_to_enum_i(self, meth, argc, argv, 0, rb_keyword_given_p());
     if (rb_block_given_p()) {
-	enumerator_ptr(lazy)->size = rb_block_proc();
+        enumerator_ptr(lazy)->size = rb_block_proc();
     }
     return lazy;
 }
@@ -1981,9 +2053,9 @@ lazyenum_yield_values(VALUE proc_entry, struct MEMO *result)
     int argc = 1;
     const VALUE *argv = &result->memo_value;
     if (LAZY_MEMO_PACKED_P(result)) {
-	const VALUE args = *argv;
-	argc = RARRAY_LENINT(args);
-	argv = RARRAY_CONST_PTR(args);
+        const VALUE args = *argv;
+        argc = RARRAY_LENINT(args);
+        argv = RARRAY_CONST_PTR(args);
     }
     return rb_proc_call_with_block(entry->proc, argc, argv, Qnil);
 }
@@ -2024,7 +2096,7 @@ static VALUE
 lazy_map(VALUE obj)
 {
     if (!rb_block_given_p()) {
-	rb_raise(rb_eArgError, "tried to call lazy map without a block");
+        rb_raise(rb_eArgError, "tried to call lazy map without a block");
     }
 
     return lazy_add_method(obj, 0, 0, Qnil, Qnil, &lazy_map_funcs);
@@ -2109,7 +2181,7 @@ static VALUE
 lazy_flat_map(VALUE obj)
 {
     if (!rb_block_given_p()) {
-	rb_raise(rb_eArgError, "tried to call lazy flat_map without a block");
+        rb_raise(rb_eArgError, "tried to call lazy flat_map without a block");
     }
 
     return lazy_add_method(obj, 0, 0, Qnil, Qnil, &lazy_flat_map_funcs);
@@ -2139,7 +2211,7 @@ static VALUE
 lazy_select(VALUE obj)
 {
     if (!rb_block_given_p()) {
-	rb_raise(rb_eArgError, "tried to call lazy select without a block");
+        rb_raise(rb_eArgError, "tried to call lazy select without a block");
     }
 
     return lazy_add_method(obj, 0, 0, Qnil, Qnil, &lazy_select_funcs);
@@ -2202,7 +2274,7 @@ static VALUE
 lazy_reject(VALUE obj)
 {
     if (!rb_block_given_p()) {
-	rb_raise(rb_eArgError, "tried to call lazy reject without a block");
+        rb_raise(rb_eArgError, "tried to call lazy reject without a block");
     }
 
     return lazy_add_method(obj, 0, 0, Qnil, Qnil, &lazy_reject_funcs);
@@ -2251,7 +2323,7 @@ static VALUE
 lazy_grep(VALUE obj, VALUE pattern)
 {
     const lazyenum_funcs *const funcs = rb_block_given_p() ?
-	&lazy_grep_iter_funcs : &lazy_grep_funcs;
+        &lazy_grep_iter_funcs : &lazy_grep_funcs;
     return lazy_add_method(obj, 0, 0, pattern, rb_ary_new3(1, pattern), funcs);
 }
 
@@ -2325,7 +2397,7 @@ lazy_zip_arrays_func(VALUE proc_entry, struct MEMO *result, VALUE memos, long me
     ary = rb_ary_new2(RARRAY_LEN(arrays) + 1);
     rb_ary_push(ary, result->memo_value);
     for (i = 0; i < RARRAY_LEN(arrays); i++) {
-	rb_ary_push(ary, rb_ary_entry(RARRAY_AREF(arrays, i), count));
+        rb_ary_push(ary, rb_ary_entry(RARRAY_AREF(arrays, i), count));
     }
     LAZY_MEMO_SET_VALUE(result, ary);
     LAZY_MEMO_SET_PACKED(result);
@@ -2343,19 +2415,19 @@ lazy_zip_func(VALUE proc_entry, struct MEMO *result, VALUE memos, long memo_inde
     long i;
 
     if (NIL_P(arg)) {
-	arg = rb_ary_new2(RARRAY_LEN(zip_args));
-	for (i = 0; i < RARRAY_LEN(zip_args); i++) {
-	    rb_ary_push(arg, rb_funcall(RARRAY_AREF(zip_args, i), id_to_enum, 0));
-	}
-	rb_ary_store(memos, memo_index, arg);
+        arg = rb_ary_new2(RARRAY_LEN(zip_args));
+        for (i = 0; i < RARRAY_LEN(zip_args); i++) {
+            rb_ary_push(arg, rb_funcall(RARRAY_AREF(zip_args, i), id_to_enum, 0));
+        }
+        rb_ary_store(memos, memo_index, arg);
     }
 
     ary = rb_ary_new2(RARRAY_LEN(arg) + 1);
     rb_ary_push(ary, result->memo_value);
     for (i = 0; i < RARRAY_LEN(arg); i++) {
-	v = rb_rescue2(call_next, RARRAY_AREF(arg, i), next_stopped, 0,
-		       rb_eStopIteration, (VALUE)0);
-	rb_ary_push(ary, v);
+        v = rb_rescue2(call_next, RARRAY_AREF(arg, i), next_stopped, 0,
+                       rb_eStopIteration, (VALUE)0);
+        rb_ary_push(ary, v);
     }
     LAZY_MEMO_SET_VALUE(result, ary);
     LAZY_MEMO_SET_PACKED(result);
@@ -2383,24 +2455,24 @@ lazy_zip(int argc, VALUE *argv, VALUE obj)
     const lazyenum_funcs *funcs = &lazy_zip_funcs[1];
 
     if (rb_block_given_p()) {
-	return rb_call_super(argc, argv);
+        return rb_call_super(argc, argv);
     }
 
     ary = rb_ary_new2(argc);
     for (i = 0; i < argc; i++) {
-	v = rb_check_array_type(argv[i]);
-	if (NIL_P(v)) {
-	    for (; i < argc; i++) {
-		if (!rb_respond_to(argv[i], id_each)) {
-		    rb_raise(rb_eTypeError, "wrong argument type %"PRIsVALUE" (must respond to :each)",
-			     rb_obj_class(argv[i]));
-		}
-	    }
-	    ary = rb_ary_new4(argc, argv);
-	    funcs = &lazy_zip_funcs[0];
-	    break;
-	}
-	rb_ary_push(ary, v);
+        v = rb_check_array_type(argv[i]);
+        if (NIL_P(v)) {
+            for (; i < argc; i++) {
+                if (!rb_respond_to(argv[i], id_each)) {
+                    rb_raise(rb_eTypeError, "wrong argument type %"PRIsVALUE" (must respond to :each)",
+                             rb_obj_class(argv[i]));
+                }
+            }
+            ary = rb_ary_new4(argc, argv);
+            funcs = &lazy_zip_funcs[0];
+            break;
+        }
+        rb_ary_push(ary, v);
     }
 
     return lazy_add_method(obj, 0, 0, ary, ary, funcs);
@@ -2414,17 +2486,12 @@ lazy_take_proc(VALUE proc_entry, struct MEMO *result, VALUE memos, long memo_ind
     VALUE memo = rb_ary_entry(memos, memo_index);
 
     if (NIL_P(memo)) {
-	memo = entry->memo;
+        memo = entry->memo;
     }
 
     remain = NUM2LONG(memo);
-    if (remain == 0) {
-	LAZY_MEMO_SET_BREAK(result);
-    }
-    else {
-	if (--remain == 0) LAZY_MEMO_SET_BREAK(result);
-	rb_ary_store(memos, memo_index, LONG2NUM(remain));
-    }
+    if (--remain == 0) LAZY_MEMO_SET_BREAK(result);
+    rb_ary_store(memos, memo_index, LONG2NUM(remain));
     return result;
 }
 
@@ -2433,12 +2500,19 @@ lazy_take_size(VALUE entry, VALUE receiver)
 {
     long len = NUM2LONG(RARRAY_AREF(rb_ivar_get(entry, id_arguments), 0));
     if (NIL_P(receiver) || (FIXNUM_P(receiver) && FIX2LONG(receiver) < len))
-	return receiver;
+        return receiver;
     return LONG2NUM(len);
 }
 
+static int
+lazy_take_precheck(VALUE proc_entry)
+{
+    struct proc_entry *entry = proc_entry_ptr(proc_entry);
+    return entry->memo != INT2FIX(0);
+}
+
 static const lazyenum_funcs lazy_take_funcs = {
-    lazy_take_proc, lazy_take_size,
+    lazy_take_proc, lazy_take_size, lazy_take_precheck,
 };
 
 /*
@@ -2452,20 +2526,14 @@ static VALUE
 lazy_take(VALUE obj, VALUE n)
 {
     long len = NUM2LONG(n);
-    int argc = 0;
-    VALUE argv[2];
 
     if (len < 0) {
-	rb_raise(rb_eArgError, "attempt to take negative size");
+        rb_raise(rb_eArgError, "attempt to take negative size");
     }
 
-    if (len == 0) {
-       argv[0] = sym_cycle;
-       argv[1] = INT2NUM(0);
-       argc = 2;
-    }
+    n = LONG2NUM(len);          /* no more conversion */
 
-    return lazy_add_method(obj, argc, argv, n, rb_ary_new3(1, n), &lazy_take_funcs);
+    return lazy_add_method(obj, 0, 0, n, rb_ary_new3(1, n), &lazy_take_funcs);
 }
 
 static struct MEMO *
@@ -2473,8 +2541,8 @@ lazy_take_while_proc(VALUE proc_entry, struct MEMO *result, VALUE memos, long me
 {
     VALUE take = lazyenum_yield_values(proc_entry, result);
     if (!RTEST(take)) {
-	LAZY_MEMO_SET_BREAK(result);
-	return 0;
+        LAZY_MEMO_SET_BREAK(result);
+        return 0;
     }
     return result;
 }
@@ -2494,7 +2562,7 @@ static VALUE
 lazy_take_while(VALUE obj)
 {
     if (!rb_block_given_p()) {
-	rb_raise(rb_eArgError, "tried to call lazy take_while without a block");
+        rb_raise(rb_eArgError, "tried to call lazy take_while without a block");
     }
 
     return lazy_add_method(obj, 0, 0, Qnil, Qnil, &lazy_take_while_funcs);
@@ -2505,10 +2573,10 @@ lazy_drop_size(VALUE proc_entry, VALUE receiver)
 {
     long len = NUM2LONG(RARRAY_AREF(rb_ivar_get(proc_entry, id_arguments), 0));
     if (NIL_P(receiver))
-	return receiver;
+        return receiver;
     if (FIXNUM_P(receiver)) {
-	len = FIX2LONG(receiver) - len;
-	return LONG2FIX(len < 0 ? 0 : len);
+        len = FIX2LONG(receiver) - len;
+        return LONG2FIX(len < 0 ? 0 : len);
     }
     return rb_funcall(receiver, '-', 1, LONG2NUM(len));
 }
@@ -2521,13 +2589,13 @@ lazy_drop_proc(VALUE proc_entry, struct MEMO *result, VALUE memos, long memo_ind
     VALUE memo = rb_ary_entry(memos, memo_index);
 
     if (NIL_P(memo)) {
-	memo = entry->memo;
+        memo = entry->memo;
     }
     remain = NUM2LONG(memo);
     if (remain > 0) {
-	--remain;
-	rb_ary_store(memos, memo_index, LONG2NUM(remain));
-	return 0;
+        --remain;
+        rb_ary_store(memos, memo_index, LONG2NUM(remain));
+        return 0;
     }
 
     return result;
@@ -2553,7 +2621,7 @@ lazy_drop(VALUE obj, VALUE n)
     argv[1] = n;
 
     if (len < 0) {
-	rb_raise(rb_eArgError, "attempt to drop negative size");
+        rb_raise(rb_eArgError, "attempt to drop negative size");
     }
 
     return lazy_add_method(obj, 2, argv, n, rb_ary_new3(1, n), &lazy_drop_funcs);
@@ -2566,13 +2634,13 @@ lazy_drop_while_proc(VALUE proc_entry, struct MEMO* result, VALUE memos, long me
     VALUE memo = rb_ary_entry(memos, memo_index);
 
     if (NIL_P(memo)) {
-	memo = entry->memo;
+        memo = entry->memo;
     }
 
     if (!RTEST(memo)) {
-	VALUE drop = lazyenum_yield_values(proc_entry, result);
-	if (RTEST(drop)) return 0;
-	rb_ary_store(memos, memo_index, Qtrue);
+        VALUE drop = lazyenum_yield_values(proc_entry, result);
+        if (RTEST(drop)) return 0;
+        rb_ary_store(memos, memo_index, Qtrue);
     }
     return result;
 }
@@ -2592,7 +2660,7 @@ static VALUE
 lazy_drop_while(VALUE obj)
 {
     if (!rb_block_given_p()) {
-	rb_raise(rb_eArgError, "tried to call lazy drop_while without a block");
+        rb_raise(rb_eArgError, "tried to call lazy drop_while without a block");
     }
 
     return lazy_add_method(obj, 0, 0, Qfalse, Qnil, &lazy_drop_while_funcs);
@@ -2747,7 +2815,8 @@ lazy_with_index(int argc, VALUE *argv, VALUE obj)
  *
  *  Like Enumerable#chunk, but chains operation to be lazy-evaluated.
  */
-static VALUE lazy_chunk(VALUE self)
+static VALUE
+lazy_chunk(VALUE self)
 {
 }
 
@@ -2757,7 +2826,8 @@ static VALUE lazy_chunk(VALUE self)
  *
  *  Like Enumerable#chunk_while, but chains operation to be lazy-evaluated.
  */
-static VALUE lazy_chunk_while(VALUE self)
+static VALUE
+lazy_chunk_while(VALUE self)
 {
 }
 
@@ -2768,7 +2838,8 @@ static VALUE lazy_chunk_while(VALUE self)
  *
  *  Like Enumerable#slice_after, but chains operation to be lazy-evaluated.
  */
-static VALUE lazy_slice_after(VALUE self)
+static VALUE
+lazy_slice_after(VALUE self)
 {
 }
 
@@ -2779,7 +2850,8 @@ static VALUE lazy_slice_after(VALUE self)
  *
  *  Like Enumerable#slice_before, but chains operation to be lazy-evaluated.
  */
-static VALUE lazy_slice_before(VALUE self)
+static VALUE
+lazy_slice_before(VALUE self)
 {
 }
 
@@ -2789,7 +2861,8 @@ static VALUE lazy_slice_before(VALUE self)
  *
  *  Like Enumerable#slice_when, but chains operation to be lazy-evaluated.
  */
-static VALUE lazy_slice_when(VALUE self)
+static VALUE
+lazy_slice_when(VALUE self)
 {
 }
 # endif
@@ -2911,7 +2984,7 @@ producer_ptr(VALUE obj)
     struct producer *ptr;
 
     TypedData_Get_Struct(obj, struct producer, &producer_data_type, ptr);
-    if (!ptr || ptr->proc == Qundef) {
+    if (!ptr || UNDEF_P(ptr->proc)) {
         rb_raise(rb_eArgError, "uninitialized producer");
     }
     return ptr;
@@ -2966,7 +3039,7 @@ producer_each_i(VALUE obj)
     init = ptr->init;
     proc = ptr->proc;
 
-    if (init == Qundef) {
+    if (UNDEF_P(init)) {
         curr = Qnil;
     }
     else {
@@ -3097,7 +3170,7 @@ enum_chain_ptr(VALUE obj)
     struct enum_chain *ptr;
 
     TypedData_Get_Struct(obj, struct enum_chain, &enum_chain_data_type, ptr);
-    if (!ptr || ptr->enums == Qundef) {
+    if (!ptr || UNDEF_P(ptr->enums)) {
         rb_raise(rb_eArgError, "uninitialized chain");
     }
     return ptr;
@@ -3290,7 +3363,7 @@ inspect_enum_chain(VALUE obj, VALUE dummy, int recur)
 
     TypedData_Get_Struct(obj, struct enum_chain, &enum_chain_data_type, ptr);
 
-    if (!ptr || ptr->enums == Qundef) {
+    if (!ptr || UNDEF_P(ptr->enums)) {
         return rb_sprintf("#<%"PRIsVALUE": uninitialized>", rb_class_path(klass));
     }
 
@@ -3348,6 +3421,356 @@ enumerator_plus(VALUE obj, VALUE eobj)
 }
 
 /*
+ * Document-class: Enumerator::Product
+ *
+ * Enumerator::Product generates a Cartesian product of any number of
+ * enumerable objects.  Iterating over the product of enumerable
+ * objects is roughly equivalent to nested each_entry loops where the
+ * loop for the rightmost object is put innermost.
+ *
+ *   innings = Enumerator::Product.new(1..9, ['top', 'bottom'])
+ *
+ *   innings.each do |i, h|
+ *     p [i, h]
+ *   end
+ *   # [1, "top"]
+ *   # [1, "bottom"]
+ *   # [2, "top"]
+ *   # [2, "bottom"]
+ *   # [3, "top"]
+ *   # [3, "bottom"]
+ *   # ...
+ *   # [9, "top"]
+ *   # [9, "bottom"]
+ *
+ * The method used against each enumerable object is `each_entry`
+ * instead of `each` so that the product of N enumerable objects
+ * yields an array of exactly N elements in each iteration.
+ *
+ * When no enumerator is given, it calls a given block once yielding
+ * an empty argument list.
+ *
+ * This type of objects can be created by Enumerator.product.
+ */
+
+static void
+enum_product_mark(void *p)
+{
+    struct enum_product *ptr = p;
+    rb_gc_mark_movable(ptr->enums);
+}
+
+static void
+enum_product_compact(void *p)
+{
+    struct enum_product *ptr = p;
+    ptr->enums = rb_gc_location(ptr->enums);
+}
+
+#define enum_product_free RUBY_TYPED_DEFAULT_FREE
+
+static size_t
+enum_product_memsize(const void *p)
+{
+    return sizeof(struct enum_product);
+}
+
+static const rb_data_type_t enum_product_data_type = {
+    "product",
+    {
+        enum_product_mark,
+        enum_product_free,
+        enum_product_memsize,
+        enum_product_compact,
+    },
+    0, 0, RUBY_TYPED_FREE_IMMEDIATELY
+};
+
+static struct enum_product *
+enum_product_ptr(VALUE obj)
+{
+    struct enum_product *ptr;
+
+    TypedData_Get_Struct(obj, struct enum_product, &enum_product_data_type, ptr);
+    if (!ptr || UNDEF_P(ptr->enums)) {
+        rb_raise(rb_eArgError, "uninitialized product");
+    }
+    return ptr;
+}
+
+/* :nodoc: */
+static VALUE
+enum_product_allocate(VALUE klass)
+{
+    struct enum_product *ptr;
+    VALUE obj;
+
+    obj = TypedData_Make_Struct(klass, struct enum_product, &enum_product_data_type, ptr);
+    ptr->enums = Qundef;
+
+    return obj;
+}
+
+/*
+ * call-seq:
+ *   Enumerator::Product.new(*enums) -> enum
+ *
+ * Generates a new enumerator object that generates a Cartesian
+ * product of given enumerable objects.
+ *
+ *   e = Enumerator::Product.new(1..3, [4, 5])
+ *   e.to_a #=> [[1, 4], [1, 5], [2, 4], [2, 5], [3, 4], [3, 5]]
+ *   e.size #=> 6
+ */
+static VALUE
+enum_product_initialize(int argc, VALUE *argv, VALUE obj)
+{
+    struct enum_product *ptr;
+    VALUE enums = Qnil, options = Qnil;
+
+    rb_scan_args(argc, argv, "*:", &enums, &options);
+
+    if (!NIL_P(options) && !RHASH_EMPTY_P(options)) {
+        rb_exc_raise(rb_keyword_error_new("unknown", rb_hash_keys(options)));
+    }
+
+    rb_check_frozen(obj);
+    TypedData_Get_Struct(obj, struct enum_product, &enum_product_data_type, ptr);
+
+    if (!ptr) rb_raise(rb_eArgError, "unallocated product");
+
+    ptr->enums = rb_obj_freeze(enums);
+
+    return obj;
+}
+
+/* :nodoc: */
+static VALUE
+enum_product_init_copy(VALUE obj, VALUE orig)
+{
+    struct enum_product *ptr0, *ptr1;
+
+    if (!OBJ_INIT_COPY(obj, orig)) return obj;
+    ptr0 = enum_product_ptr(orig);
+
+    TypedData_Get_Struct(obj, struct enum_product, &enum_product_data_type, ptr1);
+
+    if (!ptr1) rb_raise(rb_eArgError, "unallocated product");
+
+    ptr1->enums = ptr0->enums;
+
+    return obj;
+}
+
+static VALUE
+enum_product_total_size(VALUE enums)
+{
+    VALUE total = INT2FIX(1);
+    long i;
+
+    for (i = 0; i < RARRAY_LEN(enums); i++) {
+        VALUE size = enum_size(RARRAY_AREF(enums, i));
+
+        if (NIL_P(size) || (RB_TYPE_P(size, T_FLOAT) && isinf(NUM2DBL(size)))) {
+            return size;
+        }
+        if (!RB_INTEGER_TYPE_P(size)) {
+            return Qnil;
+        }
+
+        total = rb_funcall(total, '*', 1, size);
+    }
+
+    return total;
+}
+
+/*
+ * call-seq:
+ *   obj.size -> int, Float::INFINITY or nil
+ *
+ * Returns the total size of the enumerator product calculated by
+ * multiplying the sizes of enumerables in the product.  If any of the
+ * enumerables reports its size as nil or Float::INFINITY, that value
+ * is returned as the size.
+ */
+static VALUE
+enum_product_size(VALUE obj)
+{
+    return enum_product_total_size(enum_product_ptr(obj)->enums);
+}
+
+static VALUE
+enum_product_enum_size(VALUE obj, VALUE args, VALUE eobj)
+{
+    return enum_product_size(obj);
+}
+
+struct product_state {
+    VALUE  obj;
+    VALUE  block;
+    int    argc;
+    VALUE *argv;
+    int    index;
+};
+
+static VALUE product_each(VALUE, struct product_state *);
+
+static VALUE
+product_each_i(RB_BLOCK_CALL_FUNC_ARGLIST(value, state))
+{
+    struct product_state *pstate = (struct product_state *)state;
+    pstate->argv[pstate->index++] = value;
+
+    VALUE val = product_each(pstate->obj, pstate);
+    pstate->index--;
+    return val;
+}
+
+static VALUE
+product_each(VALUE obj, struct product_state *pstate)
+{
+    struct enum_product *ptr = enum_product_ptr(obj);
+    VALUE enums = ptr->enums;
+
+    if (pstate->index < pstate->argc) {
+        VALUE eobj = RARRAY_AREF(enums, pstate->index);
+
+        rb_block_call(eobj, id_each_entry, 0, NULL, product_each_i, (VALUE)pstate);
+    }
+    else {
+        rb_funcall(pstate->block, id_call, 1, rb_ary_new_from_values(pstate->argc, pstate->argv));
+    }
+
+    return obj;
+}
+
+static VALUE
+enum_product_run(VALUE obj, VALUE block)
+{
+    struct enum_product *ptr = enum_product_ptr(obj);
+    int argc = RARRAY_LENINT(ptr->enums);
+    struct product_state state = {
+        .obj = obj,
+        .block = block,
+        .index = 0,
+        .argc = argc,
+        .argv = ALLOCA_N(VALUE, argc),
+    };
+
+    return product_each(obj, &state);
+}
+
+/*
+ * call-seq:
+ *   obj.each { |...| ... } -> obj
+ *   obj.each -> enumerator
+ *
+ * Iterates over the elements of the first enumerable by calling the
+ * "each_entry" method on it with the given arguments, then proceeds
+ * to the following enumerables in sequence until all of the
+ * enumerables are exhausted.
+ *
+ * If no block is given, returns an enumerator.  Otherwise, returns self.
+ */
+static VALUE
+enum_product_each(VALUE obj)
+{
+    RETURN_SIZED_ENUMERATOR(obj, 0, 0, enum_product_enum_size);
+
+    return enum_product_run(obj, rb_block_proc());
+}
+
+/*
+ * call-seq:
+ *   obj.rewind -> obj
+ *
+ * Rewinds the product enumerator by calling the "rewind" method on
+ * each enumerable in reverse order.  Each call is performed only if
+ * the enumerable responds to the method.
+ */
+static VALUE
+enum_product_rewind(VALUE obj)
+{
+    struct enum_product *ptr = enum_product_ptr(obj);
+    VALUE enums = ptr->enums;
+    long i;
+
+    for (i = 0; i < RARRAY_LEN(enums); i++) {
+        rb_check_funcall(RARRAY_AREF(enums, i), id_rewind, 0, 0);
+    }
+
+    return obj;
+}
+
+static VALUE
+inspect_enum_product(VALUE obj, VALUE dummy, int recur)
+{
+    VALUE klass = rb_obj_class(obj);
+    struct enum_product *ptr;
+
+    TypedData_Get_Struct(obj, struct enum_product, &enum_product_data_type, ptr);
+
+    if (!ptr || UNDEF_P(ptr->enums)) {
+        return rb_sprintf("#<%"PRIsVALUE": uninitialized>", rb_class_path(klass));
+    }
+
+    if (recur) {
+        return rb_sprintf("#<%"PRIsVALUE": ...>", rb_class_path(klass));
+    }
+
+    return rb_sprintf("#<%"PRIsVALUE": %+"PRIsVALUE">", rb_class_path(klass), ptr->enums);
+}
+
+/*
+ * call-seq:
+ *   obj.inspect -> string
+ *
+ * Returns a printable version of the product enumerator.
+ */
+static VALUE
+enum_product_inspect(VALUE obj)
+{
+    return rb_exec_recursive(inspect_enum_product, obj, 0);
+}
+
+/*
+ * call-seq:
+ *   Enumerator.product(*enums) -> enumerator
+ *   Enumerator.product(*enums) { |elts| ... } -> enumerator
+ *
+ * Generates a new enumerator object that generates a Cartesian
+ * product of given enumerable objects.  This is equivalent to
+ * Enumerator::Product.new.
+ *
+ *   e = Enumerator.product(1..3, [4, 5])
+ *   e.to_a #=> [[1, 4], [1, 5], [2, 4], [2, 5], [3, 4], [3, 5]]
+ *   e.size #=> 6
+ *
+ * When a block is given, calls the block with each N-element array
+ * generated and returns +nil+.
+ */
+static VALUE
+enumerator_s_product(int argc, VALUE *argv, VALUE klass)
+{
+    VALUE enums = Qnil, options = Qnil, block = Qnil;
+
+    rb_scan_args(argc, argv, "*:&", &enums, &options, &block);
+
+    if (!NIL_P(options) && !RHASH_EMPTY_P(options)) {
+        rb_exc_raise(rb_keyword_error_new("unknown", rb_hash_keys(options)));
+    }
+
+    VALUE obj = enum_product_initialize(argc, argv, enum_product_allocate(rb_cEnumProduct));
+
+    if (!NIL_P(block)) {
+        enum_product_run(obj, block);
+        return Qnil;
+    }
+
+    return obj;
+}
+
+/*
  * Document-class: Enumerator::ArithmeticSequence
  *
  * Enumerator::ArithmeticSequence is a subclass of Enumerator,
@@ -3459,6 +3882,13 @@ rb_arithmetic_sequence_beg_len_step(VALUE obj, long *begp, long *lenp, long *ste
     *stepp = step;
 
     if (step < 0) {
+        if (aseq.exclude_end && !NIL_P(aseq.end)) {
+            /* Handle exclusion before range reversal */
+            aseq.end = LONG2NUM(NUM2LONG(aseq.end) + 1);
+
+            /* Don't exclude the previous beginning */
+            aseq.exclude_end = 0;
+        }
         VALUE tmp = aseq.begin;
         aseq.begin = aseq.end;
         aseq.end = tmp;
@@ -4214,6 +4644,22 @@ InitVM_Enumerator(void)
     rb_undef_method(rb_cEnumChain, "peek");
     rb_undef_method(rb_cEnumChain, "peek_values");
 
+    /* Product */
+    rb_cEnumProduct = rb_define_class_under(rb_cEnumerator, "Product", rb_cEnumerator);
+    rb_define_alloc_func(rb_cEnumProduct, enum_product_allocate);
+    rb_define_method(rb_cEnumProduct, "initialize", enum_product_initialize, -1);
+    rb_define_method(rb_cEnumProduct, "initialize_copy", enum_product_init_copy, 1);
+    rb_define_method(rb_cEnumProduct, "each", enum_product_each, 0);
+    rb_define_method(rb_cEnumProduct, "size", enum_product_size, 0);
+    rb_define_method(rb_cEnumProduct, "rewind", enum_product_rewind, 0);
+    rb_define_method(rb_cEnumProduct, "inspect", enum_product_inspect, 0);
+    rb_undef_method(rb_cEnumProduct, "feed");
+    rb_undef_method(rb_cEnumProduct, "next");
+    rb_undef_method(rb_cEnumProduct, "next_values");
+    rb_undef_method(rb_cEnumProduct, "peek");
+    rb_undef_method(rb_cEnumProduct, "peek_values");
+    rb_define_singleton_method(rb_cEnumerator, "product", enumerator_s_product, -1);
+
     /* ArithmeticSequence */
     rb_cArithSeq = rb_define_class_under(rb_cEnumerator, "ArithmeticSequence", rb_cEnumerator);
     rb_undef_alloc_func(rb_cArithSeq);
@@ -4249,6 +4695,7 @@ Init_Enumerator(void)
     id_method = rb_intern_const("method");
     id_force = rb_intern_const("force");
     id_to_enum = rb_intern_const("to_enum");
+    id_each_entry = rb_intern_const("each_entry");
     id_begin = rb_intern_const("begin");
     id_end = rb_intern_const("end");
     id_step = rb_intern_const("step");
diff --git a/error.c b/error.c
index 24df7ce064..726f57a4c0 100644
--- a/error.c
+++ b/error.c
@@ -34,6 +34,7 @@
 #include "internal/io.h"
 #include "internal/load.h"
 #include "internal/object.h"
+#include "internal/string.h"
 #include "internal/symbol.h"
 #include "internal/thread.h"
 #include "internal/variable.h"
@@ -82,7 +83,7 @@ static struct {
     st_table *id2enum, *enum2id;
 } warning_categories;
 
-extern const char ruby_description[];
+extern const char *rb_dynamic_description;
 
 static const char *
 rb_strerrno(int err)
@@ -99,54 +100,48 @@ static int
 err_position_0(char *buf, long len, const char *file, int line)
 {
     if (!file) {
-	return 0;
+        return 0;
     }
     else if (line == 0) {
-	return snprintf(buf, len, "%s: ", file);
+        return snprintf(buf, len, "%s: ", file);
     }
     else {
-	return snprintf(buf, len, "%s:%d: ", file, line);
+        return snprintf(buf, len, "%s:%d: ", file, line);
     }
 }
 
 RBIMPL_ATTR_FORMAT(RBIMPL_PRINTF_FORMAT, 5, 0)
 static VALUE
 err_vcatf(VALUE str, const char *pre, const char *file, int line,
-	  const char *fmt, va_list args)
+          const char *fmt, va_list args)
 {
     if (file) {
-	rb_str_cat2(str, file);
-	if (line) rb_str_catf(str, ":%d", line);
-	rb_str_cat2(str, ": ");
+        rb_str_cat2(str, file);
+        if (line) rb_str_catf(str, ":%d", line);
+        rb_str_cat2(str, ": ");
     }
     if (pre) rb_str_cat2(str, pre);
     rb_str_vcatf(str, fmt, args);
     return str;
 }
 
+static VALUE syntax_error_with_path(VALUE, VALUE, VALUE*, rb_encoding*);
+
 VALUE
 rb_syntax_error_append(VALUE exc, VALUE file, int line, int column,
-		       rb_encoding *enc, const char *fmt, va_list args)
+                       rb_encoding *enc, const char *fmt, va_list args)
 {
     const char *fn = NIL_P(file) ? NULL : RSTRING_PTR(file);
     if (!exc) {
-	VALUE mesg = rb_enc_str_new(0, 0, enc);
-	err_vcatf(mesg, NULL, fn, line, fmt, args);
-	rb_str_cat2(mesg, "\n");
-	rb_write_error_str(mesg);
+        VALUE mesg = rb_enc_str_new(0, 0, enc);
+        err_vcatf(mesg, NULL, fn, line, fmt, args);
+        rb_str_cat2(mesg, "\n");
+        rb_write_error_str(mesg);
     }
     else {
-	VALUE mesg;
-	if (NIL_P(exc)) {
-	    mesg = rb_enc_str_new(0, 0, enc);
-	    exc = rb_class_new_instance(1, &mesg, rb_eSyntaxError);
-	}
-	else {
-	    mesg = rb_attr_get(exc, idMesg);
-	    if (RSTRING_LEN(mesg) > 0 && *(RSTRING_END(mesg)-1) != '\n')
-		rb_str_cat_cstr(mesg, "\n");
-	}
-	err_vcatf(mesg, NULL, fn, line, fmt, args);
+        VALUE mesg;
+        exc = syntax_error_with_path(exc, file, &mesg, enc);
+        err_vcatf(mesg, NULL, fn, line, fmt, args);
     }
 
     return exc;
@@ -357,47 +352,42 @@ warn_vsprintf(rb_encoding *enc, const char *file, int line, const char *fmt, va_
     return rb_str_cat2(str, "\n");
 }
 
+#define with_warn_vsprintf(file, line, fmt) \
+    VALUE str; \
+    va_list args; \
+    va_start(args, fmt); \
+    str = warn_vsprintf(NULL, file, line, fmt, args); \
+    va_end(args);
+
 void
 rb_compile_warn(const char *file, int line, const char *fmt, ...)
 {
-    VALUE str;
-    va_list args;
-
-    if (NIL_P(ruby_verbose)) return;
-
-    va_start(args, fmt);
-    str = warn_vsprintf(NULL, file, line, fmt, args);
-    va_end(args);
-    rb_write_warning_str(str);
+    if (!NIL_P(ruby_verbose)) {
+        with_warn_vsprintf(file, line, fmt) {
+            rb_write_warning_str(str);
+        }
+    }
 }
 
 /* rb_compile_warning() reports only in verbose mode */
 void
 rb_compile_warning(const char *file, int line, const char *fmt, ...)
 {
-    VALUE str;
-    va_list args;
-
-    if (!RTEST(ruby_verbose)) return;
-
-    va_start(args, fmt);
-    str = warn_vsprintf(NULL, file, line, fmt, args);
-    va_end(args);
-    rb_write_warning_str(str);
+    if (RTEST(ruby_verbose)) {
+        with_warn_vsprintf(file, line, fmt) {
+            rb_write_warning_str(str);
+        }
+    }
 }
 
 void
 rb_category_compile_warn(rb_warning_category_t category, const char *file, int line, const char *fmt, ...)
 {
-    VALUE str;
-    va_list args;
-
-    if (NIL_P(ruby_verbose)) return;
-
-    va_start(args, fmt);
-    str = warn_vsprintf(NULL, file, line, fmt, args);
-    va_end(args);
-    rb_warn_category(str, rb_warning_category_to_name(category));
+    if (!NIL_P(ruby_verbose)) {
+        with_warn_vsprintf(file, line, fmt) {
+            rb_warn_category(str, rb_warning_category_to_name(category));
+        }
+    }
 }
 
 RBIMPL_ATTR_FORMAT(RBIMPL_PRINTF_FORMAT, 2, 0)
@@ -410,8 +400,10 @@ warning_string(rb_encoding *enc, const char *fmt, va_list args)
 }
 
 #define with_warning_string(mesg, enc, fmt) \
+    with_warning_string_from(mesg, enc, fmt, fmt)
+#define with_warning_string_from(mesg, enc, fmt, last_arg) \
     VALUE mesg; \
-    va_list args; va_start(args, fmt); \
+    va_list args; va_start(args, last_arg); \
     mesg = warning_string(enc, fmt, args); \
     va_end(args);
 
@@ -419,16 +411,16 @@ void
 rb_warn(const char *fmt, ...)
 {
     if (!NIL_P(ruby_verbose)) {
-	with_warning_string(mesg, 0, fmt) {
-	    rb_write_warning_str(mesg);
-	}
+        with_warning_string(mesg, 0, fmt) {
+            rb_write_warning_str(mesg);
+        }
     }
 }
 
 void
 rb_category_warn(rb_warning_category_t category, const char *fmt, ...)
 {
-    if (!NIL_P(ruby_verbose)) {
+    if (!NIL_P(ruby_verbose) && rb_warning_category_enabled_p(category)) {
         with_warning_string(mesg, 0, fmt) {
             rb_warn_category(mesg, rb_warning_category_to_name(category));
         }
@@ -439,9 +431,9 @@ void
 rb_enc_warn(rb_encoding *enc, const char *fmt, ...)
 {
     if (!NIL_P(ruby_verbose)) {
-	with_warning_string(mesg, enc, fmt) {
-	    rb_write_warning_str(mesg);
-	}
+        with_warning_string(mesg, enc, fmt) {
+            rb_write_warning_str(mesg);
+        }
     }
 }
 
@@ -450,9 +442,9 @@ void
 rb_warning(const char *fmt, ...)
 {
     if (RTEST(ruby_verbose)) {
-	with_warning_string(mesg, 0, fmt) {
-	    rb_write_warning_str(mesg);
-	}
+        with_warning_string(mesg, 0, fmt) {
+            rb_write_warning_str(mesg);
+        }
     }
 }
 
@@ -460,7 +452,7 @@ rb_warning(const char *fmt, ...)
 void
 rb_category_warning(rb_warning_category_t category, const char *fmt, ...)
 {
-    if (RTEST(ruby_verbose)) {
+    if (RTEST(ruby_verbose) && rb_warning_category_enabled_p(category)) {
         with_warning_string(mesg, 0, fmt) {
             rb_warn_category(mesg, rb_warning_category_to_name(category));
         }
@@ -480,9 +472,9 @@ void
 rb_enc_warning(rb_encoding *enc, const char *fmt, ...)
 {
     if (RTEST(ruby_verbose)) {
-	with_warning_string(mesg, enc, fmt) {
-	    rb_write_warning_str(mesg);
-	}
+        with_warning_string(mesg, enc, fmt) {
+            rb_write_warning_str(mesg);
+        }
     }
 }
 #endif
@@ -513,12 +505,9 @@ rb_warn_deprecated(const char *fmt, const char *suggest, ...)
 {
     if (!deprecation_warning_enabled()) return;
 
-    va_list args;
-    va_start(args, suggest);
-    VALUE mesg = warning_string(0, fmt, args);
-    va_end(args);
-
-    warn_deprecated(mesg, NULL, suggest);
+    with_warning_string_from(mesg, 0, fmt, suggest) {
+        warn_deprecated(mesg, NULL, suggest);
+    }
 }
 
 void
@@ -526,19 +515,16 @@ rb_warn_deprecated_to_remove(const char *removal, const char *fmt, const char *s
 {
     if (!deprecation_warning_enabled()) return;
 
-    va_list args;
-    va_start(args, suggest);
-    VALUE mesg = warning_string(0, fmt, args);
-    va_end(args);
-
-    warn_deprecated(mesg, removal, suggest);
+    with_warning_string_from(mesg, 0, fmt, suggest) {
+        warn_deprecated(mesg, removal, suggest);
+    }
 }
 
 static inline int
 end_with_asciichar(VALUE str, int c)
 {
     return RB_TYPE_P(str, T_STRING) &&
-	rb_str_end_with_asciichar(str, c);
+        rb_str_end_with_asciichar(str, c);
 }
 
 /* :nodoc: */
@@ -546,7 +532,7 @@ static VALUE
 warning_write(int argc, VALUE *argv, VALUE buf)
 {
     while (argc-- > 0) {
-	rb_str_append(buf, *argv++);
+        rb_str_append(buf, *argv++);
     }
     return buf;
 }
@@ -571,38 +557,38 @@ rb_warn_m(rb_execution_context_t *ec, VALUE exc, VALUE msgs, VALUE uplevel, VALU
             if (!NIL_P(location)) {
                 location = rb_ary_entry(location, 0);
             }
-	}
-	if (argc > 1 || !NIL_P(uplevel) || !end_with_asciichar(str, '\n')) {
-	    VALUE path;
-	    if (NIL_P(uplevel)) {
-		str = rb_str_tmp_new(0);
-	    }
-	    else if (NIL_P(location) ||
-		     NIL_P(path = rb_funcall(location, rb_intern("path"), 0))) {
-		str = rb_str_new_cstr("warning: ");
-	    }
-	    else {
-		str = rb_sprintf("%s:%ld: warning: ",
-		    rb_string_value_ptr(&path),
-		    NUM2LONG(rb_funcall(location, rb_intern("lineno"), 0)));
-	    }
-	    RBASIC_SET_CLASS(str, rb_cWarningBuffer);
-	    rb_io_puts(argc, argv, str);
-	    RBASIC_SET_CLASS(str, rb_cString);
-	}
+        }
+        if (argc > 1 || !NIL_P(uplevel) || !end_with_asciichar(str, '\n')) {
+            VALUE path;
+            if (NIL_P(uplevel)) {
+                str = rb_str_tmp_new(0);
+            }
+            else if (NIL_P(location) ||
+                     NIL_P(path = rb_funcall(location, rb_intern("path"), 0))) {
+                str = rb_str_new_cstr("warning: ");
+            }
+            else {
+                str = rb_sprintf("%s:%ld: warning: ",
+                    rb_string_value_ptr(&path),
+                    NUM2LONG(rb_funcall(location, rb_intern("lineno"), 0)));
+            }
+            RBASIC_SET_CLASS(str, rb_cWarningBuffer);
+            rb_io_puts(argc, argv, str);
+            RBASIC_SET_CLASS(str, rb_cString);
+        }
 
         if (!NIL_P(category)) {
             category = rb_to_symbol_type(category);
             rb_warning_category_from_name(category);
         }
 
-	if (exc == rb_mWarning) {
-	    rb_must_asciicompat(str);
-	    rb_write_error_str(str);
-	}
-	else {
+        if (exc == rb_mWarning) {
+            rb_must_asciicompat(str);
+            rb_write_error_str(str);
+        }
+        else {
             rb_warn_category(str, category);
-	}
+        }
     }
     return Qnil;
 }
@@ -621,7 +607,7 @@ rb_bug_reporter_add(void (*func)(FILE *, void *), void *data)
 {
     struct bug_reporters *reporter;
     if (bug_reporters_size >= MAX_BUG_REPORTERS) {
-	return 0; /* failed to register */
+        return 0; /* failed to register */
     }
     reporter = &bug_reporters[bug_reporters_size++];
     reporter->func = func;
@@ -640,7 +626,7 @@ bug_report_file(const char *file, int line)
     int len = err_position_0(buf, sizeof(buf), file, line);
 
     if ((ssize_t)fwrite(buf, 1, len, out) == (ssize_t)len ||
-	(ssize_t)fwrite(buf, 1, len, (out = stdout)) == (ssize_t)len) {
+        (ssize_t)fwrite(buf, 1, len, (out = stdout)) == (ssize_t)len) {
         return out;
     }
 
@@ -657,40 +643,45 @@ bug_important_message(FILE *out, const char *const msg, size_t len)
 
     if (!len) return;
     if (isatty(fileno(out))) {
-	static const char red[] = "\033[;31;1;7m";
-	static const char green[] = "\033[;32;7m";
-	static const char reset[] = "\033[m";
-	const char *e = strchr(p, '\n');
-	const int w = (int)(e - p);
-	do {
-	    int i = (int)(e - p);
-	    fputs(*p == ' ' ? green : red, out);
-	    fwrite(p, 1, e - p, out);
-	    for (; i < w; ++i) fputc(' ', out);
-	    fputs(reset, out);
-	    fputc('\n', out);
-	} while ((p = e + 1) < endmsg && (e = strchr(p, '\n')) != 0 && e > p + 1);
+        static const char red[] = "\033[;31;1;7m";
+        static const char green[] = "\033[;32;7m";
+        static const char reset[] = "\033[m";
+        const char *e = strchr(p, '\n');
+        const int w = (int)(e - p);
+        do {
+            int i = (int)(e - p);
+            fputs(*p == ' ' ? green : red, out);
+            fwrite(p, 1, e - p, out);
+            for (; i < w; ++i) fputc(' ', out);
+            fputs(reset, out);
+            fputc('\n', out);
+        } while ((p = e + 1) < endmsg && (e = strchr(p, '\n')) != 0 && e > p + 1);
     }
     fwrite(p, 1, endmsg - p, out);
 }
 
+#undef CRASH_REPORTER_MAY_BE_CREATED
+#if defined(__APPLE__) && \
+    (!defined(MAC_OS_X_VERSION_10_6) || MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_6 || defined(__POWERPC__)) /* 10.6 PPC case */
+# define CRASH_REPORTER_MAY_BE_CREATED
+#endif
 static void
 preface_dump(FILE *out)
 {
 #if defined __APPLE__
     static const char msg[] = ""
-	"-- Crash Report log information "
-	"--------------------------------------------\n"
-	"   See Crash Report log file in one of the following locations:\n"
-# if MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_6
-	"     * ~/Library/Logs/CrashReporter\n"
-	"     * /Library/Logs/CrashReporter\n"
+        "-- Crash Report log information "
+        "--------------------------------------------\n"
+        "   See Crash Report log file in one of the following locations:\n"
+# ifdef CRASH_REPORTER_MAY_BE_CREATED
+        "     * ~/Library/Logs/CrashReporter\n"
+        "     * /Library/Logs/CrashReporter\n"
 # endif
-	"     * ~/Library/Logs/DiagnosticReports\n"
-	"     * /Library/Logs/DiagnosticReports\n"
-	"   for more details.\n"
-	"Don't forget to include the above Crash Report log file in bug reports.\n"
-	"\n";
+        "     * ~/Library/Logs/DiagnosticReports\n"
+        "     * /Library/Logs/DiagnosticReports\n"
+        "   for more details.\n"
+        "Don't forget to include the above Crash Report log file in bug reports.\n"
+        "\n";
     const size_t msglen = sizeof(msg) - 1;
 #else
     const char *msg = NULL;
@@ -704,15 +695,15 @@ postscript_dump(FILE *out)
 {
 #if defined __APPLE__
     static const char msg[] = ""
-	"[IMPORTANT]"
-	/*" ------------------------------------------------"*/
-	"\n""Don't forget to include the Crash Report log file under\n"
-# if MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_10_6
-	"CrashReporter or "
+        "[IMPORTANT]"
+        /*" ------------------------------------------------"*/
+        "\n""Don't forget to include the Crash Report log file under\n"
+# ifdef CRASH_REPORTER_MAY_BE_CREATED
+        "CrashReporter or "
 # endif
-	"DiagnosticReports directory in bug reports.\n"
-	/*"------------------------------------------------------------\n"*/
-	"\n";
+        "DiagnosticReports directory in bug reports.\n"
+        /*"------------------------------------------------------------\n"*/
+        "\n";
     const size_t msglen = sizeof(msg) - 1;
 #else
     const char *msg = NULL;
@@ -730,7 +721,7 @@ bug_report_begin_valist(FILE *out, const char *fmt, va_list args)
     fputs("[BUG] ", out);
     vsnprintf(buf, sizeof(buf), fmt, args);
     fputs(buf, out);
-    snprintf(buf, sizeof(buf), "\n%s\n\n", ruby_description);
+    snprintf(buf, sizeof(buf), "\n%s\n\n", rb_dynamic_description);
     fputs(buf, out);
     preface_dump(out);
 }
@@ -747,11 +738,11 @@ bug_report_end(FILE *out)
 {
     /* call additional bug reporters */
     {
-	int i;
-	for (i=0; i<bug_reporters_size; i++) {
-	    struct bug_reporters *reporter = &bug_reporters[i];
-	    (*reporter->func)(out, reporter->data);
-	}
+        int i;
+        for (i=0; i<bug_reporters_size; i++) {
+            struct bug_reporters *reporter = &bug_reporters[i];
+            (*reporter->func)(out, reporter->data);
+        }
     }
     postscript_dump(out);
 }
@@ -759,18 +750,18 @@ bug_report_end(FILE *out)
 #define report_bug(file, line, fmt, ctx) do { \
     FILE *out = bug_report_file(file, line); \
     if (out) { \
-	bug_report_begin(out, fmt); \
-	rb_vm_bugreport(ctx); \
-	bug_report_end(out); \
+        bug_report_begin(out, fmt); \
+        rb_vm_bugreport(ctx); \
+        bug_report_end(out); \
     } \
 } while (0) \
 
 #define report_bug_valist(file, line, fmt, ctx, args) do { \
     FILE *out = bug_report_file(file, line); \
     if (out) { \
-	bug_report_begin_valist(out, fmt, args); \
-	rb_vm_bugreport(ctx); \
-	bug_report_end(out); \
+        bug_report_begin_valist(out, fmt, args); \
+        rb_vm_bugreport(ctx); \
+        bug_report_end(out); \
     } \
 } while (0) \
 
@@ -816,7 +807,7 @@ rb_bug_for_fatal_signal(ruby_sighandler_t default_sighandler, int sig, const voi
     int line = 0;
 
     if (GET_EC()) {
-	file = rb_source_location_cstr(&line);
+        file = rb_source_location_cstr(&line);
     }
 
     report_bug(file, line, fmt, ctx);
@@ -856,17 +847,17 @@ rb_async_bug_errno(const char *mesg, int errno_arg)
     WRITE_CONST(2, "\n");
 
     if (errno_arg == 0) {
-	WRITE_CONST(2, "errno == 0 (NOERROR)\n");
+        WRITE_CONST(2, "errno == 0 (NOERROR)\n");
     }
     else {
-	const char *errno_str = rb_strerrno(errno_arg);
+        const char *errno_str = rb_strerrno(errno_arg);
 
-	if (!errno_str)
-	    errno_str = "undefined errno";
-	write_or_abort(2, errno_str, strlen(errno_str));
+        if (!errno_str)
+            errno_str = "undefined errno";
+        write_or_abort(2, errno_str, strlen(errno_str));
     }
     WRITE_CONST(2, "\n\n");
-    write_or_abort(2, ruby_description, strlen(ruby_description));
+    write_or_abort(2, rb_dynamic_description, strlen(rb_dynamic_description));
     abort();
 }
 
@@ -882,7 +873,7 @@ rb_assert_failure(const char *file, int line, const char *name, const char *expr
     FILE *out = stderr;
     fprintf(out, "Assertion Failed: %s:%d:", file, line);
     if (name) fprintf(out, "%s:", name);
-    fprintf(out, "%s\n%s\n\n", expr, ruby_description);
+    fprintf(out, "%s\n%s\n\n", expr, rb_dynamic_description);
     preface_dump(out);
     rb_vm_bugreport(NULL);
     bug_report_end(out);
@@ -948,22 +939,22 @@ builtin_class_name(VALUE x)
     const char *etype;
 
     if (NIL_P(x)) {
-	etype = "nil";
+        etype = "nil";
     }
     else if (FIXNUM_P(x)) {
-	etype = "Integer";
+        etype = "Integer";
     }
     else if (SYMBOL_P(x)) {
-	etype = "Symbol";
+        etype = "Symbol";
     }
     else if (RB_TYPE_P(x, T_TRUE)) {
-	etype = "true";
+        etype = "true";
     }
     else if (RB_TYPE_P(x, T_FALSE)) {
-	etype = "false";
+        etype = "false";
     }
     else {
-	etype = NULL;
+        etype = NULL;
     }
     return etype;
 }
@@ -974,7 +965,7 @@ rb_builtin_class_name(VALUE x)
     const char *etype = builtin_class_name(x);
 
     if (!etype) {
-	etype = rb_obj_classname(x);
+        etype = rb_obj_classname(x);
     }
     return etype;
 }
@@ -991,14 +982,14 @@ unexpected_type(VALUE x, int xt, int t)
     if (tname) {
         mesg = rb_sprintf("wrong argument type %"PRIsVALUE" (expected %s)",
                           displaying_class_of(x), tname);
-	exc = rb_eTypeError;
+        exc = rb_eTypeError;
     }
     else if (xt > T_MASK && xt <= 0x3f) {
-	mesg = rb_sprintf("unknown type 0x%x (0x%x given, probably comes"
-			  " from extension library for ruby 1.8)", t, xt);
+        mesg = rb_sprintf("unknown type 0x%x (0x%x given, probably comes"
+                          " from extension library for ruby 1.8)", t, xt);
     }
     else {
-	mesg = rb_sprintf("unknown type 0x%x (0x%x given)", t, xt);
+        mesg = rb_sprintf("unknown type 0x%x (0x%x given)", t, xt);
     }
     rb_exc_raise(rb_exc_new_str(exc, mesg));
 }
@@ -1008,8 +999,8 @@ rb_check_type(VALUE x, int t)
 {
     int xt;
 
-    if (RB_UNLIKELY(x == Qundef)) {
-	rb_bug(UNDEF_LEAKED);
+    if (RB_UNLIKELY(UNDEF_P(x))) {
+        rb_bug(UNDEF_LEAKED);
     }
 
     xt = TYPE(x);
@@ -1022,15 +1013,15 @@ rb_check_type(VALUE x, int t)
          * So it is not enough to just check `T_DATA`, it must be
          * identified by its `type` using `Check_TypedStruct` instead.
          */
-	unexpected_type(x, xt, t);
+        unexpected_type(x, xt, t);
     }
 }
 
 void
 rb_unexpected_type(VALUE x, int t)
 {
-    if (RB_UNLIKELY(x == Qundef)) {
-	rb_bug(UNDEF_LEAKED);
+    if (RB_UNLIKELY(UNDEF_P(x))) {
+        rb_bug(UNDEF_LEAKED);
     }
 
     unexpected_type(x, TYPE(x), t);
@@ -1040,8 +1031,8 @@ int
 rb_typeddata_inherited_p(const rb_data_type_t *child, const rb_data_type_t *parent)
 {
     while (child) {
-	if (child == parent) return 1;
-	child = child->parent;
+        if (child == parent) return 1;
+        child = child->parent;
     }
     return 0;
 }
@@ -1050,8 +1041,8 @@ int
 rb_typeddata_is_kind_of(VALUE obj, const rb_data_type_t *data_type)
 {
     if (!RB_TYPE_P(obj, T_DATA) ||
-	!RTYPEDDATA_P(obj) || !rb_typeddata_inherited_p(RTYPEDDATA_TYPE(obj), data_type)) {
-	return 0;
+        !RTYPEDDATA_P(obj) || !rb_typeddata_inherited_p(RTYPEDDATA_TYPE(obj), data_type)) {
+        return 0;
     }
     return 1;
 }
@@ -1231,7 +1222,7 @@ VALUE
 rb_get_message(VALUE exc)
 {
     VALUE e = rb_check_funcall(exc, id_message, 0, 0);
-    if (e == Qundef) return Qnil;
+    if (UNDEF_P(e)) return Qnil;
     if (!RB_TYPE_P(e, T_STRING)) e = rb_check_string_type(e);
     return e;
 }
@@ -1246,7 +1237,7 @@ rb_get_detailed_message(VALUE exc, VALUE opt)
     else {
         e = rb_check_funcall_kw(exc, id_detailed_message, 1, &opt, 1);
     }
-    if (e == Qundef) return Qnil;
+    if (UNDEF_P(e)) return Qnil;
     if (!RB_TYPE_P(e, T_STRING)) e = rb_check_string_type(e);
     return e;
 }
@@ -1269,24 +1260,18 @@ check_highlight_keyword(VALUE opt, int auto_tty_detect)
     VALUE highlight = Qnil;
 
     if (!NIL_P(opt)) {
-        highlight = rb_hash_aref(opt, sym_highlight);
+        highlight = rb_hash_lookup(opt, sym_highlight);
 
         switch (highlight) {
           default:
-            rb_bool_expected(highlight, "highlight");
+            rb_bool_expected(highlight, "highlight", TRUE);
             UNREACHABLE;
-          case Qundef: highlight = Qnil; break;
           case Qtrue: case Qfalse: case Qnil: break;
         }
     }
 
     if (NIL_P(highlight)) {
-        if (auto_tty_detect) {
-            highlight = rb_stderr_tty_p() ? Qtrue : Qfalse;
-        }
-        else {
-            highlight = Qfalse;
-        }
+        highlight = RBOOL(auto_tty_detect && rb_stderr_tty_p());
     }
 
     return highlight;
@@ -1301,7 +1286,7 @@ check_order_keyword(VALUE opt)
         static VALUE kw_order;
         if (!kw_order) kw_order = ID2SYM(rb_intern_const("order"));
 
-        order = rb_hash_aref(opt, kw_order);
+        order = rb_hash_lookup(opt, kw_order);
 
         if (order != Qnil) {
             ID id = rb_check_id(&order);
@@ -1391,6 +1376,28 @@ exc_message(VALUE exc)
  *
  * This method is overridden by did_you_mean and error_highlight to add
  * their information.
+ *
+ * A user-defined exception class can also define their own
+ * +detailed_message+ method to add supplemental information.
+ * When +highlight+ is true, it can return a string containing escape
+ * sequences, but use widely-supported ones. It is recommended to limit
+ * the following codes:
+ *
+ * - Reset (+\e[0m+)
+ * - Bold (+\e[1m+)
+ * - Underline (+\e[4m+)
+ * - Foreground color except white and black
+ *   - Red (+\e[31m+)
+ *   - Green (+\e[32m+)
+ *   - Yellow (+\e[33m+)
+ *   - Blue (+\e[34m+)
+ *   - Magenta (+\e[35m+)
+ *   - Cyan (+\e[36m+)
+ *
+ * Use escape sequences carefully even if +highlight+ is true.
+ * Do not use escape sequences to express essential information;
+ * the message should be readable even if all escape sequences are
+ * ignored.
  */
 
 static VALUE
@@ -1428,8 +1435,15 @@ exc_inspect(VALUE exc)
     str = rb_str_buf_new2("#<");
     klass = rb_class_name(klass);
     rb_str_buf_append(str, klass);
-    rb_str_buf_cat(str, ": ", 2);
-    rb_str_buf_append(str, exc);
+
+    if (RTEST(rb_str_include(exc, rb_str_new2("\n")))) {
+        rb_str_catf(str, ":%+"PRIsVALUE, exc);
+    }
+    else {
+        rb_str_buf_cat(str, ": ", 2);
+        rb_str_buf_append(str, exc);
+    }
+
     rb_str_buf_cat(str, ">", 1);
 
     return str;
@@ -1478,8 +1492,8 @@ exc_backtrace(VALUE exc)
     obj = rb_attr_get(exc, id_bt);
 
     if (rb_backtrace_p(obj)) {
-	obj = rb_backtrace_to_str_ary(obj);
-	/* rb_ivar_set(exc, id_bt, obj); */
+        obj = rb_backtrace_to_str_ary(obj);
+        /* rb_ivar_set(exc, id_bt, obj); */
     }
 
     return obj;
@@ -1493,16 +1507,16 @@ rb_get_backtrace(VALUE exc)
     ID mid = id_backtrace;
     VALUE info;
     if (rb_method_basic_definition_p(CLASS_OF(exc), id_backtrace)) {
-	VALUE klass = rb_eException;
-	rb_execution_context_t *ec = GET_EC();
-	if (NIL_P(exc))
-	    return Qnil;
-	EXEC_EVENT_HOOK(ec, RUBY_EVENT_C_CALL, exc, mid, mid, klass, Qundef);
-	info = exc_backtrace(exc);
-	EXEC_EVENT_HOOK(ec, RUBY_EVENT_C_RETURN, exc, mid, mid, klass, info);
+        VALUE klass = rb_eException;
+        rb_execution_context_t *ec = GET_EC();
+        if (NIL_P(exc))
+            return Qnil;
+        EXEC_EVENT_HOOK(ec, RUBY_EVENT_C_CALL, exc, mid, mid, klass, Qundef);
+        info = exc_backtrace(exc);
+        EXEC_EVENT_HOOK(ec, RUBY_EVENT_C_RETURN, exc, mid, mid, klass, info);
     }
     else {
-	info = rb_funcallv(exc, mid, 0, 0);
+        info = rb_funcallv(exc, mid, 0, 0);
     }
     if (NIL_P(info)) return Qnil;
     return rb_check_backtrace(info);
@@ -1525,7 +1539,7 @@ exc_backtrace_locations(VALUE exc)
 
     obj = rb_attr_get(exc, id_bt_locations);
     if (!NIL_P(obj)) {
-	obj = rb_backtrace_to_location_ary(obj);
+        obj = rb_backtrace_to_location_ary(obj);
     }
     return obj;
 }
@@ -1537,17 +1551,17 @@ rb_check_backtrace(VALUE bt)
     static const char err[] = "backtrace must be Array of String";
 
     if (!NIL_P(bt)) {
-	if (RB_TYPE_P(bt, T_STRING)) return rb_ary_new3(1, bt);
-	if (rb_backtrace_p(bt)) return bt;
-	if (!RB_TYPE_P(bt, T_ARRAY)) {
-	    rb_raise(rb_eTypeError, err);
-	}
-	for (i=0;i<RARRAY_LEN(bt);i++) {
-	    VALUE e = RARRAY_AREF(bt, i);
-	    if (!RB_TYPE_P(e, T_STRING)) {
-		rb_raise(rb_eTypeError, err);
-	    }
-	}
+        if (RB_TYPE_P(bt, T_STRING)) return rb_ary_new3(1, bt);
+        if (rb_backtrace_p(bt)) return bt;
+        if (!RB_TYPE_P(bt, T_ARRAY)) {
+            rb_raise(rb_eTypeError, err);
+        }
+        for (i=0;i<RARRAY_LEN(bt);i++) {
+            VALUE e = RARRAY_AREF(bt, i);
+            if (!RB_TYPE_P(e, T_STRING)) {
+                rb_raise(rb_eTypeError, err);
+            }
+        }
     }
     return bt;
 }
@@ -1612,26 +1626,26 @@ exc_equal(VALUE exc, VALUE obj)
     if (exc == obj) return Qtrue;
 
     if (rb_obj_class(exc) != rb_obj_class(obj)) {
-	int state;
-
-	obj = rb_protect(try_convert_to_exception, obj, &state);
-	if (state || obj == Qundef) {
-	    rb_set_errinfo(Qnil);
-	    return Qfalse;
-	}
-	if (rb_obj_class(exc) != rb_obj_class(obj)) return Qfalse;
-	mesg = rb_check_funcall(obj, id_message, 0, 0);
-	if (mesg == Qundef) return Qfalse;
-	backtrace = rb_check_funcall(obj, id_backtrace, 0, 0);
-	if (backtrace == Qundef) return Qfalse;
+        int state;
+
+        obj = rb_protect(try_convert_to_exception, obj, &state);
+        if (state || UNDEF_P(obj)) {
+            rb_set_errinfo(Qnil);
+            return Qfalse;
+        }
+        if (rb_obj_class(exc) != rb_obj_class(obj)) return Qfalse;
+        mesg = rb_check_funcall(obj, id_message, 0, 0);
+        if (UNDEF_P(mesg)) return Qfalse;
+        backtrace = rb_check_funcall(obj, id_backtrace, 0, 0);
+        if (UNDEF_P(backtrace)) return Qfalse;
     }
     else {
-	mesg = rb_attr_get(obj, id_mesg);
-	backtrace = exc_backtrace(obj);
+        mesg = rb_attr_get(obj, id_mesg);
+        backtrace = exc_backtrace(obj);
     }
 
     if (!rb_equal(rb_attr_get(exc, id_mesg), mesg))
-	return Qfalse;
+        return Qfalse;
     return rb_equal(exc_backtrace(exc), backtrace);
 }
 
@@ -1652,37 +1666,37 @@ exit_initialize(int argc, VALUE *argv, VALUE exc)
 {
     VALUE status;
     if (argc > 0) {
-	status = *argv;
-
-	switch (status) {
-	  case Qtrue:
-	    status = INT2FIX(EXIT_SUCCESS);
-	    ++argv;
-	    --argc;
-	    break;
-	  case Qfalse:
-	    status = INT2FIX(EXIT_FAILURE);
-	    ++argv;
-	    --argc;
-	    break;
-	  default:
-	    status = rb_check_to_int(status);
-	    if (NIL_P(status)) {
-		status = INT2FIX(EXIT_SUCCESS);
-	    }
-	    else {
+        status = *argv;
+
+        switch (status) {
+          case Qtrue:
+            status = INT2FIX(EXIT_SUCCESS);
+            ++argv;
+            --argc;
+            break;
+          case Qfalse:
+            status = INT2FIX(EXIT_FAILURE);
+            ++argv;
+            --argc;
+            break;
+          default:
+            status = rb_check_to_int(status);
+            if (NIL_P(status)) {
+                status = INT2FIX(EXIT_SUCCESS);
+            }
+            else {
 #if EXIT_SUCCESS != 0
-		if (status == INT2FIX(0))
-		    status = INT2FIX(EXIT_SUCCESS);
+                if (status == INT2FIX(0))
+                    status = INT2FIX(EXIT_SUCCESS);
 #endif
-		++argv;
-		--argc;
-	    }
-	    break;
-	}
+                ++argv;
+                --argc;
+            }
+            break;
+        }
     }
     else {
-	status = INT2FIX(EXIT_SUCCESS);
+        status = INT2FIX(EXIT_SUCCESS);
     }
     rb_call_super(argc, argv);
     rb_ivar_set(exc, id_status, status);
@@ -1718,7 +1732,7 @@ exit_success_p(VALUE exc)
     int status;
 
     if (NIL_P(status_val))
-	return Qtrue;
+        return Qtrue;
     status = NUM2INT(status_val);
     return RBOOL(WIFEXITED(status) && WEXITSTATUS(status) == EXIT_SUCCESS);
 }
@@ -1726,7 +1740,7 @@ exit_success_p(VALUE exc)
 static VALUE
 err_init_recv(VALUE exc, VALUE recv)
 {
-    if (recv != Qundef) rb_ivar_set(exc, id_recv, recv);
+    if (!UNDEF_P(recv)) rb_ivar_set(exc, id_recv, recv);
     return exc;
 }
 
@@ -1804,7 +1818,9 @@ name_err_init_attr(VALUE exc, VALUE recv, VALUE method)
     cfp = rb_vm_get_ruby_level_next_cfp(ec, cfp);
     rb_ivar_set(exc, id_name, method);
     err_init_recv(exc, recv);
-    if (cfp) rb_ivar_set(exc, id_iseq, rb_iseqw_new(cfp->iseq));
+    if (cfp && VM_FRAME_TYPE(cfp) != VM_FRAME_MAGIC_DUMMY) {
+        rb_ivar_set(exc, id_iseq, rb_iseqw_new(cfp->iseq));
+    }
     return exc;
 }
 
@@ -1881,10 +1897,10 @@ name_err_local_variables(VALUE self)
     VALUE vars = rb_attr_get(self, id_local_variables);
 
     if (NIL_P(vars)) {
-	VALUE iseqw = rb_attr_get(self, id_iseq);
-	if (!NIL_P(iseqw)) vars = rb_iseqw_local_variables(iseqw);
-	if (NIL_P(vars)) vars = rb_ary_new();
-	rb_ivar_set(self, id_local_variables, vars);
+        VALUE iseqw = rb_attr_get(self, id_iseq);
+        if (!NIL_P(iseqw)) vars = rb_iseqw_local_variables(iseqw);
+        if (NIL_P(vars)) vars = rb_ary_new();
+        rb_ivar_set(self, id_local_variables, vars);
     }
     return vars;
 }
@@ -1960,9 +1976,9 @@ name_err_mesg_memsize(const void *p)
 static const rb_data_type_t name_err_mesg_data_type = {
     "name_err_mesg",
     {
-	name_err_mesg_mark,
-	name_err_mesg_free,
-	name_err_mesg_memsize,
+        name_err_mesg_mark,
+        name_err_mesg_free,
+        name_err_mesg_memsize,
     },
     0, 0, RUBY_TYPED_FREE_IMMEDIATELY
 };
@@ -2019,13 +2035,13 @@ name_err_mesg_equal(VALUE obj1, VALUE obj2)
 
     if (obj1 == obj2) return Qtrue;
     if (rb_obj_class(obj2) != rb_cNameErrorMesg)
-	return Qfalse;
+        return Qfalse;
 
     TypedData_Get_Struct(obj1, VALUE, &name_err_mesg_data_type, ptr1);
     TypedData_Get_Struct(obj2, VALUE, &name_err_mesg_data_type, ptr2);
     for (i=0; i<NAME_ERR_MESG_COUNT; i++) {
-	if (!rb_equal(ptr1[i], ptr2[i]))
-	    return Qfalse;
+        if (!rb_equal(ptr1[i], ptr2[i]))
+            return Qfalse;
     }
     return Qtrue;
 }
@@ -2051,49 +2067,49 @@ name_err_mesg_to_str(VALUE obj)
     mesg = ptr[NAME_ERR_MESG__MESG];
     if (NIL_P(mesg)) return Qnil;
     else {
-	struct RString s_str, d_str;
-	VALUE c, s, d = 0, args[4];
-	int state = 0, singleton = 0;
-	rb_encoding *usascii = rb_usascii_encoding();
+        struct RString s_str, d_str;
+        VALUE c, s, d = 0, args[4];
+        int state = 0, singleton = 0;
+        rb_encoding *usascii = rb_usascii_encoding();
 
 #define FAKE_CSTR(v, str) rb_setup_fake_str((v), (str), rb_strlen_lit(str), usascii)
-	obj = ptr[NAME_ERR_MESG__RECV];
-	switch (obj) {
-	  case Qnil:
-	    d = FAKE_CSTR(&d_str, "nil");
-	    break;
-	  case Qtrue:
-	    d = FAKE_CSTR(&d_str, "true");
-	    break;
-	  case Qfalse:
-	    d = FAKE_CSTR(&d_str, "false");
-	    break;
-	  default:
-	    d = rb_protect(name_err_mesg_receiver_name, obj, &state);
-	    if (state || d == Qundef || NIL_P(d))
-		d = rb_protect(rb_inspect, obj, &state);
-	    if (state) {
-		rb_set_errinfo(Qnil);
-	    }
-	    d = rb_check_string_type(d);
-	    if (NIL_P(d)) {
-		d = rb_any_to_s(obj);
-	    }
-	    singleton = (RSTRING_LEN(d) > 0 && RSTRING_PTR(d)[0] == '#');
-	    break;
-	}
-	if (!singleton) {
-	    s = FAKE_CSTR(&s_str, ":");
-	    c = rb_class_name(CLASS_OF(obj));
-	}
-	else {
-	    c = s = FAKE_CSTR(&s_str, "");
-	}
+        obj = ptr[NAME_ERR_MESG__RECV];
+        switch (obj) {
+          case Qnil:
+            d = FAKE_CSTR(&d_str, "nil");
+            break;
+          case Qtrue:
+            d = FAKE_CSTR(&d_str, "true");
+            break;
+          case Qfalse:
+            d = FAKE_CSTR(&d_str, "false");
+            break;
+          default:
+            d = rb_protect(name_err_mesg_receiver_name, obj, &state);
+            if (state || NIL_OR_UNDEF_P(d))
+                d = rb_protect(rb_inspect, obj, &state);
+            if (state) {
+                rb_set_errinfo(Qnil);
+            }
+            d = rb_check_string_type(d);
+            if (NIL_P(d)) {
+                d = rb_any_to_s(obj);
+            }
+            singleton = (RSTRING_LEN(d) > 0 && RSTRING_PTR(d)[0] == '#');
+            break;
+        }
+        if (!singleton) {
+            s = FAKE_CSTR(&s_str, ":");
+            c = rb_class_name(CLASS_OF(obj));
+        }
+        else {
+            c = s = FAKE_CSTR(&s_str, "");
+        }
         args[0] = rb_obj_as_string(ptr[NAME_ERR_MESG__NAME]);
-	args[1] = d;
-	args[2] = s;
-	args[3] = c;
-	mesg = rb_str_format(4, args, mesg);
+        args[1] = d;
+        args[2] = s;
+        args[3] = c;
+        mesg = rb_str_format(4, args, mesg);
     }
     return mesg;
 }
@@ -2125,11 +2141,11 @@ name_err_receiver(VALUE self)
     VALUE *ptr, recv, mesg;
 
     recv = rb_ivar_lookup(self, id_recv, Qundef);
-    if (recv != Qundef) return recv;
+    if (!UNDEF_P(recv)) return recv;
 
     mesg = rb_attr_get(self, id_mesg);
     if (!rb_typeddata_is_kind_of(mesg, &name_err_mesg_data_type)) {
-	rb_raise(rb_eArgError, "no receiver is available");
+        rb_raise(rb_eArgError, "no receiver is available");
     }
     ptr = DATA_PTR(mesg);
     return ptr[NAME_ERR_MESG__RECV];
@@ -2183,7 +2199,7 @@ key_err_receiver(VALUE self)
     VALUE recv;
 
     recv = rb_ivar_lookup(self, id_receiver, Qundef);
-    if (recv != Qundef) return recv;
+    if (!UNDEF_P(recv)) return recv;
     rb_raise(rb_eArgError, "no receiver is available");
 }
 
@@ -2200,7 +2216,7 @@ key_err_key(VALUE self)
     VALUE key;
 
     key = rb_ivar_lookup(self, id_key, Qundef);
-    if (key != Qundef) return key;
+    if (!UNDEF_P(key)) return key;
     rb_raise(rb_eArgError, "no key is available");
 }
 
@@ -2231,17 +2247,17 @@ key_err_initialize(int argc, VALUE *argv, VALUE self)
     rb_call_super(rb_scan_args(argc, argv, "01:", NULL, &options), argv);
 
     if (!NIL_P(options)) {
-	ID keywords[2];
-	VALUE values[numberof(keywords)];
-	int i;
-	keywords[0] = id_receiver;
-	keywords[1] = id_key;
-	rb_get_kwargs(options, keywords, 0, numberof(values), values);
-	for (i = 0; i < numberof(values); ++i) {
-	    if (values[i] != Qundef) {
-		rb_ivar_set(self, keywords[i], values[i]);
-	    }
-	}
+        ID keywords[2];
+        VALUE values[numberof(keywords)];
+        int i;
+        keywords[0] = id_receiver;
+        keywords[1] = id_key;
+        rb_get_kwargs(options, keywords, 0, numberof(values), values);
+        for (i = 0; i < numberof(values); ++i) {
+            if (!UNDEF_P(values[i])) {
+                rb_ivar_set(self, keywords[i], values[i]);
+            }
+        }
     }
 
     return self;
@@ -2260,7 +2276,7 @@ no_matching_pattern_key_err_matchee(VALUE self)
     VALUE matchee;
 
     matchee = rb_ivar_lookup(self, id_matchee, Qundef);
-    if (matchee != Qundef) return matchee;
+    if (!UNDEF_P(matchee)) return matchee;
     rb_raise(rb_eArgError, "no matchee is available");
 }
 
@@ -2277,7 +2293,7 @@ no_matching_pattern_key_err_key(VALUE self)
     VALUE key;
 
     key = rb_ivar_lookup(self, id_key, Qundef);
-    if (key != Qundef) return key;
+    if (!UNDEF_P(key)) return key;
     rb_raise(rb_eArgError, "no key is available");
 }
 
@@ -2304,7 +2320,7 @@ no_matching_pattern_key_err_initialize(int argc, VALUE *argv, VALUE self)
         keywords[1] = id_key;
         rb_get_kwargs(options, keywords, 0, numberof(values), values);
         for (i = 0; i < numberof(values); ++i) {
-            if (values[i] != Qundef) {
+            if (!UNDEF_P(values[i])) {
                 rb_ivar_set(self, keywords[i], values[i]);
             }
         }
@@ -2326,13 +2342,32 @@ syntax_error_initialize(int argc, VALUE *argv, VALUE self)
 {
     VALUE mesg;
     if (argc == 0) {
-	mesg = rb_fstring_lit("compile error");
-	argc = 1;
-	argv = &mesg;
+        mesg = rb_fstring_lit("compile error");
+        argc = 1;
+        argv = &mesg;
     }
     return rb_call_super(argc, argv);
 }
 
+static VALUE
+syntax_error_with_path(VALUE exc, VALUE path, VALUE *mesg, rb_encoding *enc)
+{
+    if (NIL_P(exc)) {
+        *mesg = rb_enc_str_new(0, 0, enc);
+        exc = rb_class_new_instance(1, mesg, rb_eSyntaxError);
+        rb_ivar_set(exc, id_i_path, path);
+    }
+    else {
+        if (rb_attr_get(exc, id_i_path) != path) {
+            rb_raise(rb_eArgError, "SyntaxError#path changed");
+        }
+        VALUE s = *mesg = rb_attr_get(exc, idMesg);
+        if (RSTRING_LEN(s) > 0 && *(RSTRING_END(s)-1) != '\n')
+            rb_str_cat_cstr(s, "\n");
+    }
+    return exc;
+}
+
 /*
  *  Document-module: Errno
  *
@@ -2371,30 +2406,30 @@ set_syserr(int n, const char *name)
     st_data_t error;
 
     if (!st_lookup(syserr_tbl, n, &error)) {
-	error = rb_define_class_under(rb_mErrno, name, rb_eSystemCallError);
+        error = rb_define_class_under(rb_mErrno, name, rb_eSystemCallError);
 
-	/* capture nonblock errnos for WaitReadable/WaitWritable subclasses */
-	switch (n) {
-	  case EAGAIN:
-	    rb_eEAGAIN = error;
+        /* capture nonblock errnos for WaitReadable/WaitWritable subclasses */
+        switch (n) {
+          case EAGAIN:
+            rb_eEAGAIN = error;
 
 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
-	    break;
-	  case EWOULDBLOCK:
+            break;
+          case EWOULDBLOCK:
 #endif
 
-	    rb_eEWOULDBLOCK = error;
-	    break;
-	  case EINPROGRESS:
-	    rb_eEINPROGRESS = error;
-	    break;
-	}
+            rb_eEWOULDBLOCK = error;
+            break;
+          case EINPROGRESS:
+            rb_eEINPROGRESS = error;
+            break;
+        }
 
-	rb_define_const(error, "Errno", INT2NUM(n));
-	st_add_direct(syserr_tbl, n, error);
+        rb_define_const(error, "Errno", INT2NUM(n));
+        st_add_direct(syserr_tbl, n, error);
     }
     else {
-	rb_define_const(rb_mErrno, name, error);
+        rb_define_const(rb_mErrno, name, error);
     }
     return error;
 }
@@ -2405,10 +2440,10 @@ get_syserr(int n)
     st_data_t error;
 
     if (!st_lookup(syserr_tbl, n, &error)) {
-	char name[8];	/* some Windows' errno have 5 digits. */
+        char name[8];	/* some Windows' errno have 5 digits. */
 
-	snprintf(name, sizeof(name), "E%03d", n);
-	error = set_syserr(n, name);
+        snprintf(name, sizeof(name), "E%03d", n);
+        error = set_syserr(n, name);
     }
     return error;
 }
@@ -2426,41 +2461,38 @@ get_syserr(int n)
 static VALUE
 syserr_initialize(int argc, VALUE *argv, VALUE self)
 {
-#if !defined(_WIN32)
-    char *strerror();
-#endif
     const char *err;
     VALUE mesg, error, func, errmsg;
     VALUE klass = rb_obj_class(self);
 
     if (klass == rb_eSystemCallError) {
-	st_data_t data = (st_data_t)klass;
-	rb_scan_args(argc, argv, "12", &mesg, &error, &func);
-	if (argc == 1 && FIXNUM_P(mesg)) {
-	    error = mesg; mesg = Qnil;
-	}
-	if (!NIL_P(error) && st_lookup(syserr_tbl, NUM2LONG(error), &data)) {
-	    klass = (VALUE)data;
-	    /* change class */
-	    if (!RB_TYPE_P(self, T_OBJECT)) { /* insurance to avoid type crash */
-		rb_raise(rb_eTypeError, "invalid instance type");
-	    }
-	    RBASIC_SET_CLASS(self, klass);
-	}
+        st_data_t data = (st_data_t)klass;
+        rb_scan_args(argc, argv, "12", &mesg, &error, &func);
+        if (argc == 1 && FIXNUM_P(mesg)) {
+            error = mesg; mesg = Qnil;
+        }
+        if (!NIL_P(error) && st_lookup(syserr_tbl, NUM2LONG(error), &data)) {
+            klass = (VALUE)data;
+            /* change class */
+            if (!RB_TYPE_P(self, T_OBJECT)) { /* insurance to avoid type crash */
+                rb_raise(rb_eTypeError, "invalid instance type");
+            }
+            RBASIC_SET_CLASS(self, klass);
+        }
     }
     else {
-	rb_scan_args(argc, argv, "02", &mesg, &func);
-	error = rb_const_get(klass, id_Errno);
+        rb_scan_args(argc, argv, "02", &mesg, &func);
+        error = rb_const_get(klass, id_Errno);
     }
     if (!NIL_P(error)) err = strerror(NUM2INT(error));
     else err = "unknown error";
 
     errmsg = rb_enc_str_new_cstr(err, rb_locale_encoding());
     if (!NIL_P(mesg)) {
-	VALUE str = StringValue(mesg);
+        VALUE str = StringValue(mesg);
 
-	if (!NIL_P(func)) rb_str_catf(errmsg, " @ %"PRIsVALUE, func);
-	rb_str_catf(errmsg, " - %"PRIsVALUE, str);
+        if (!NIL_P(func)) rb_str_catf(errmsg, " @ %"PRIsVALUE, func);
+        rb_str_catf(errmsg, " - %"PRIsVALUE, str);
     }
     mesg = errmsg;
 
@@ -2496,13 +2528,13 @@ syserr_eqq(VALUE self, VALUE exc)
     VALUE num, e;
 
     if (!rb_obj_is_kind_of(exc, rb_eSystemCallError)) {
-	if (!rb_respond_to(exc, id_errno)) return Qfalse;
+        if (!rb_respond_to(exc, id_errno)) return Qfalse;
     }
     else if (self == rb_eSystemCallError) return Qtrue;
 
     num = rb_attr_get(exc, id_errno);
     if (NIL_P(num)) {
-	num = rb_funcallv(exc, id_errno, 0, 0);
+        num = rb_funcallv(exc, id_errno, 0, 0);
     }
     e = rb_const_get(self, id_Errno);
     return RBOOL(FIXNUM_P(num) ? num == e : rb_equal(num, e));
@@ -2929,6 +2961,8 @@ ivar_copy_i(st_data_t key, st_data_t val, st_data_t exc)
     return ST_CONTINUE;
 }
 
+void rb_exc_check_circular_cause(VALUE exc);
+
 static VALUE
 exception_loader(VALUE exc, VALUE obj)
 {
@@ -2943,6 +2977,8 @@ exception_loader(VALUE exc, VALUE obj)
 
     rb_ivar_foreach(obj, ivar_copy_i, exc);
 
+    rb_exc_check_circular_cause(exc);
+
     if (rb_attr_get(exc, id_bt) == rb_attr_get(exc, id_bt_locations)) {
         rb_ivar_set(exc, id_bt_locations, Qnil);
     }
@@ -2994,9 +3030,16 @@ Init_Exception(void)
     rb_eSyntaxError = rb_define_class("SyntaxError", rb_eScriptError);
     rb_define_method(rb_eSyntaxError, "initialize", syntax_error_initialize, -1);
 
+    /* RDoc will use literal name value while parsing rb_attr,
+    *  and will render `idPath` as an attribute name without this trick */
+    ID path = idPath;
+
+    /* the path failed to parse */
+    rb_attr(rb_eSyntaxError, path, TRUE, FALSE, FALSE);
+
     rb_eLoadError   = rb_define_class("LoadError", rb_eScriptError);
     /* the path failed to load */
-    rb_attr(rb_eLoadError, rb_intern_const("path"), 1, 0, Qfalse);
+    rb_attr(rb_eLoadError, path, TRUE, FALSE, FALSE);
 
     rb_eNotImpError = rb_define_class("NotImplementedError", rb_eScriptError);
 
@@ -3150,8 +3193,8 @@ void
 rb_notimplement(void)
 {
     rb_raise(rb_eNotImpError,
-	     "%"PRIsVALUE"() function is unimplemented on this machine",
-	     rb_id2str(rb_frame_this_func()));
+             "%"PRIsVALUE"() function is unimplemented on this machine",
+             rb_id2str(rb_frame_this_func()));
 }
 
 void
@@ -3182,7 +3225,7 @@ make_errno_exc(const char *mesg)
 
     errno = 0;
     if (n == 0) {
-	rb_bug("rb_sys_fail(%s) - errno == 0", mesg ? mesg : "");
+        rb_bug("rb_sys_fail(%s) - errno == 0", mesg ? mesg : "");
     }
     return rb_syserr_new(n, mesg);
 }
@@ -3195,8 +3238,8 @@ make_errno_exc_str(VALUE mesg)
     errno = 0;
     if (!mesg) mesg = Qnil;
     if (n == 0) {
-	const char *s = !NIL_P(mesg) ? RSTRING_PTR(mesg) : "";
-	rb_bug("rb_sys_fail_str(%s) - errno == 0", s);
+        const char *s = !NIL_P(mesg) ? RSTRING_PTR(mesg) : "";
+        rb_bug("rb_sys_fail_str(%s) - errno == 0", s);
     }
     return rb_syserr_new_str(n, mesg);
 }
@@ -3262,10 +3305,10 @@ rb_syserr_new_path_in(const char *func_name, int n, VALUE path)
 
     if (!path) path = Qnil;
     if (n == 0) {
-	const char *s = !NIL_P(path) ? RSTRING_PTR(path) : "";
-	if (!func_name) func_name = "(null)";
-	rb_bug("rb_sys_fail_path_in(%s, %s) - errno == 0",
-	       func_name, s);
+        const char *s = !NIL_P(path) ? RSTRING_PTR(path) : "";
+        if (!func_name) func_name = "(null)";
+        rb_bug("rb_sys_fail_path_in(%s, %s) - errno == 0",
+               func_name, s);
     }
     args[0] = path;
     args[1] = rb_str_new_cstr(func_name);
@@ -3323,11 +3366,11 @@ void
 rb_sys_warn(const char *fmt, ...)
 {
     if (!NIL_P(ruby_verbose)) {
-	int errno_save = errno;
-	with_warning_string(mesg, 0, fmt) {
-	    syserr_warning(mesg, errno_save);
-	}
-	errno = errno_save;
+        int errno_save = errno;
+        with_warning_string(mesg, 0, fmt) {
+            syserr_warning(mesg, errno_save);
+        }
+        errno = errno_save;
     }
 }
 
@@ -3335,9 +3378,9 @@ void
 rb_syserr_warn(int err, const char *fmt, ...)
 {
     if (!NIL_P(ruby_verbose)) {
-	with_warning_string(mesg, 0, fmt) {
-	    syserr_warning(mesg, err);
-	}
+        with_warning_string(mesg, 0, fmt) {
+            syserr_warning(mesg, err);
+        }
     }
 }
 
@@ -3345,11 +3388,11 @@ void
 rb_sys_enc_warn(rb_encoding *enc, const char *fmt, ...)
 {
     if (!NIL_P(ruby_verbose)) {
-	int errno_save = errno;
-	with_warning_string(mesg, enc, fmt) {
-	    syserr_warning(mesg, errno_save);
-	}
-	errno = errno_save;
+        int errno_save = errno;
+        with_warning_string(mesg, enc, fmt) {
+            syserr_warning(mesg, errno_save);
+        }
+        errno = errno_save;
     }
 }
 
@@ -3357,9 +3400,9 @@ void
 rb_syserr_enc_warn(int err, rb_encoding *enc, const char *fmt, ...)
 {
     if (!NIL_P(ruby_verbose)) {
-	with_warning_string(mesg, enc, fmt) {
-	    syserr_warning(mesg, err);
-	}
+        with_warning_string(mesg, enc, fmt) {
+            syserr_warning(mesg, err);
+        }
     }
 }
 #endif
@@ -3368,11 +3411,11 @@ void
 rb_sys_warning(const char *fmt, ...)
 {
     if (RTEST(ruby_verbose)) {
-	int errno_save = errno;
-	with_warning_string(mesg, 0, fmt) {
-	    syserr_warning(mesg, errno_save);
-	}
-	errno = errno_save;
+        int errno_save = errno;
+        with_warning_string(mesg, 0, fmt) {
+            syserr_warning(mesg, errno_save);
+        }
+        errno = errno_save;
     }
 }
 
@@ -3381,9 +3424,9 @@ void
 rb_syserr_warning(int err, const char *fmt, ...)
 {
     if (RTEST(ruby_verbose)) {
-	with_warning_string(mesg, 0, fmt) {
-	    syserr_warning(mesg, err);
-	}
+        with_warning_string(mesg, 0, fmt) {
+            syserr_warning(mesg, err);
+        }
     }
 }
 #endif
@@ -3392,11 +3435,11 @@ void
 rb_sys_enc_warning(rb_encoding *enc, const char *fmt, ...)
 {
     if (RTEST(ruby_verbose)) {
-	int errno_save = errno;
-	with_warning_string(mesg, enc, fmt) {
-	    syserr_warning(mesg, errno_save);
-	}
-	errno = errno_save;
+        int errno_save = errno;
+        with_warning_string(mesg, enc, fmt) {
+            syserr_warning(mesg, errno_save);
+        }
+        errno = errno_save;
     }
 }
 
@@ -3404,9 +3447,9 @@ void
 rb_syserr_enc_warning(int err, rb_encoding *enc, const char *fmt, ...)
 {
     if (RTEST(ruby_verbose)) {
-	with_warning_string(mesg, enc, fmt) {
-	    syserr_warning(mesg, err);
-	}
+        with_warning_string(mesg, enc, fmt) {
+            syserr_warning(mesg, err);
+        }
     }
 }
 
@@ -3464,8 +3507,8 @@ rb_error_frozen_object(VALUE frozen_obj)
     rb_exec_recursive(inspect_frozen_obj, frozen_obj, mesg);
 
     if (!NIL_P(debug_info = rb_attr_get(frozen_obj, created_info))) {
-	VALUE path = rb_ary_entry(debug_info, 0);
-	VALUE line = rb_ary_entry(debug_info, 1);
+        VALUE path = rb_ary_entry(debug_info, 0);
+        VALUE line = rb_ary_entry(debug_info, 1);
 
         rb_str_catf(mesg, ", created at %"PRIsVALUE":%"PRIsVALUE, path, line);
     }
diff --git a/eval.c b/eval.c
index 237c0fbd66..a61dfb1289 100644
--- a/eval.c
+++ b/eval.c
@@ -21,6 +21,7 @@
 #include "gc.h"
 #include "internal.h"
 #include "internal/class.h"
+#include "internal/cont.h"
 #include "internal/error.h"
 #include "internal/eval.h"
 #include "internal/hash.h"
@@ -42,7 +43,7 @@ NORETURN(static void rb_raise_jump(VALUE, VALUE));
 void rb_ec_clear_current_thread_trace_func(const rb_execution_context_t *ec);
 void rb_ec_clear_all_trace_func(const rb_execution_context_t *ec);
 
-static int rb_ec_cleanup(rb_execution_context_t *ec, int ex);
+static int rb_ec_cleanup(rb_execution_context_t *ec, enum ruby_tag_type ex);
 static int rb_ec_exec_node(rb_execution_context_t *ec, void *n);
 
 VALUE rb_eLocalJumpError;
@@ -67,7 +68,7 @@ ruby_setup(void)
     enum ruby_tag_type state;
 
     if (GET_VM())
-	return 0;
+        return 0;
 
     ruby_init_stack((void *)&state);
 
@@ -85,9 +86,9 @@ ruby_setup(void)
 
     EC_PUSH_TAG(GET_EC());
     if ((state = EC_EXEC_TAG()) == TAG_NONE) {
-	rb_call_inits();
-	ruby_prog_init();
-	GET_VM()->running = 1;
+        rb_call_inits();
+        ruby_prog_init();
+        GET_VM()->running = 1;
     }
     EC_POP_TAG();
 
@@ -99,9 +100,11 @@ ruby_init(void)
 {
     int state = ruby_setup();
     if (state) {
-        if (RTEST(ruby_debug))
-            error_print(GET_EC());
-	exit(EXIT_FAILURE);
+        if (RTEST(ruby_debug)) {
+            rb_execution_context_t *ec = GET_EC();
+            rb_ec_error_print(ec, ec->errinfo);
+        }
+        exit(EXIT_FAILURE);
     }
 }
 
@@ -115,12 +118,13 @@ ruby_options(int argc, char **argv)
     ruby_init_stack((void *)&iseq);
     EC_PUSH_TAG(ec);
     if ((state = EC_EXEC_TAG()) == TAG_NONE) {
-	SAVE_ROOT_JMPBUF(GET_THREAD(), iseq = ruby_process_options(argc, argv));
+        SAVE_ROOT_JMPBUF(GET_THREAD(), iseq = ruby_process_options(argc, argv));
     }
     else {
         rb_ec_clear_current_thread_trace_func(ec);
-        state = error_handle(ec, state);
-	iseq = (void *)INT2FIX(state);
+        int exitcode = error_handle(ec, ec->errinfo, state);
+        ec->errinfo = Qnil; /* just been handled */
+        iseq = (void *)INT2FIX(exitcode);
     }
     EC_POP_TAG();
     return iseq;
@@ -136,7 +140,7 @@ rb_ec_fiber_scheduler_finalize(rb_execution_context_t *ec)
         rb_fiber_scheduler_set(Qnil);
     }
     else {
-        state = error_handle(ec, state);
+        state = error_handle(ec, ec->errinfo, state);
     }
     EC_POP_TAG();
 }
@@ -175,20 +179,21 @@ ruby_finalize(void)
 int
 ruby_cleanup(int ex)
 {
-    return rb_ec_cleanup(GET_EC(), ex);
+    return rb_ec_cleanup(GET_EC(), (enum ruby_tag_type)ex);
 }
 
 static int
-rb_ec_cleanup(rb_execution_context_t *ec, int ex0)
+rb_ec_cleanup(rb_execution_context_t *ec, enum ruby_tag_type ex)
 {
     int state;
-    volatile VALUE errs[2] = { Qundef, Qundef };
-    int nerr;
+    volatile VALUE save_error = Qundef;
+    volatile int sysex = EXIT_SUCCESS;
+    volatile int signaled = 0;
     rb_thread_t *th = rb_ec_thread_ptr(ec);
     rb_thread_t *const volatile th0 = th;
-    volatile int sysex = EXIT_SUCCESS;
     volatile int step = 0;
-    volatile int ex = ex0;
+    volatile VALUE message = Qnil;
+    VALUE buf;
 
     rb_threadptr_interrupt(th);
     rb_threadptr_check_signal(th);
@@ -198,60 +203,61 @@ rb_ec_cleanup(rb_execution_context_t *ec, int ex0)
         SAVE_ROOT_JMPBUF(th, { RUBY_VM_CHECK_INTS(ec); });
 
       step_0: step++;
-        errs[1] = ec->errinfo;
+        save_error = ec->errinfo;
         if (THROW_DATA_P(ec->errinfo)) ec->errinfo = Qnil;
-	ruby_init_stack(&errs[STACK_UPPER(errs, 0, 1)]);
+        ruby_init_stack(&message);
 
+        /* exits with failure but silently when an exception raised
+         * here */
         SAVE_ROOT_JMPBUF(th, rb_ec_teardown(ec));
 
       step_1: step++;
-	/* protect from Thread#raise */
-	th->status = THREAD_KILLED;
+        VALUE err = ec->errinfo;
+        volatile int mode0 = 0, mode1 = 0;
+        if (err != save_error && !NIL_P(err)) {
+            mode0 = exiting_split(err, &sysex, &signaled);
+        }
+
+        /* exceptions after here will be ignored */
+
+        /* build error message including causes */
+        err = ATOMIC_VALUE_EXCHANGE(save_error, Qnil);
+
+        if (!NIL_P(err) && !THROW_DATA_P(err)) {
+            mode1 = exiting_split(err, (mode0 & EXITING_WITH_STATUS) ? NULL : &sysex, &signaled);
+            if (mode1 & EXITING_WITH_MESSAGE) {
+                buf = rb_str_new(NULL, 0);
+                SAVE_ROOT_JMPBUF(th, rb_ec_error_print_detailed(ec, err, buf, Qundef));
+                message = buf;
+            }
+        }
+
+      step_2: step++;
+        /* protect from Thread#raise */
+        th->status = THREAD_KILLED;
 
-        errs[0] = ec->errinfo;
-	SAVE_ROOT_JMPBUF(th, rb_ractor_terminate_all());
+        SAVE_ROOT_JMPBUF(th, rb_ractor_terminate_all());
+
+      step_3: step++;
+        if (!NIL_P(buf = message)) {
+            warn_print_str(buf);
+        }
+        else if (!NIL_OR_UNDEF_P(err = save_error) ||
+                 (ex != TAG_NONE && !((mode0|mode1) & EXITING_WITH_STATUS))) {
+            sysex = error_handle(ec, err, ex);
+        }
     }
     else {
         th = th0;
-	switch (step) {
-	  case 0: goto step_0;
-	  case 1: goto step_1;
-	}
-	if (ex == 0) ex = state;
-    }
-    ec->errinfo = errs[1];
-    sysex = error_handle(ec, ex);
-
-    state = 0;
-    for (nerr = 0; nerr < numberof(errs); ++nerr) {
-	VALUE err = ATOMIC_VALUE_EXCHANGE(errs[nerr], Qnil);
-        VALUE sig;
-
-	if (!RTEST(err)) continue;
-
-        /* ec->errinfo contains a NODE while break'ing */
-	if (THROW_DATA_P(err)) continue;
-
-	if (rb_obj_is_kind_of(err, rb_eSystemExit)) {
-	    sysex = sysexit_status(err);
-	    break;
-	}
-	else if (rb_obj_is_kind_of(err, rb_eSignal)) {
-	    VALUE sig = rb_ivar_get(err, id_signo);
-	    state = NUM2INT(sig);
-	    break;
-	}
-        else if (rb_obj_is_kind_of(err, rb_eSystemCallError) &&
-                 FIXNUM_P(sig = rb_attr_get(err, id_signo))) {
-	    state = NUM2INT(sig);
-	    break;
+        switch (step) {
+          case 0: goto step_0;
+          case 1: goto step_1;
+          case 2: goto step_2;
+          case 3: goto step_3;
         }
-	else if (sysex == EXIT_SUCCESS) {
-	    sysex = EXIT_FAILURE;
-	}
     }
 
-    mjit_finish(true); // We still need ISeqs here.
+    mjit_finish(true); // We still need ISeqs here, so it's before rb_ec_finalize().
 
     rb_ec_finalize(ec);
 
@@ -262,7 +268,10 @@ rb_ec_cleanup(rb_execution_context_t *ec, int ex0)
     th = th0;
     rb_thread_stop_timer_thread();
     ruby_vm_destruct(th->vm);
-    if (state) ruby_default_signal(state);
+    // For YJIT, call this after ruby_vm_destruct() frees jit_cont for the root fiber.
+    rb_jit_cont_finish();
+
+    if (signaled) ruby_default_signal(signaled);
 
     return sysex;
 }
@@ -277,9 +286,9 @@ rb_ec_exec_node(rb_execution_context_t *ec, void *n)
     EC_PUSH_TAG(ec);
     if ((state = EC_EXEC_TAG()) == TAG_NONE) {
         rb_thread_t *const th = rb_ec_thread_ptr(ec);
-	SAVE_ROOT_JMPBUF(th, {
-	    rb_iseq_eval_main(iseq);
-	});
+        SAVE_ROOT_JMPBUF(th, {
+            rb_iseq_eval_main(iseq);
+        });
     }
     EC_POP_TAG();
     return state;
@@ -301,8 +310,8 @@ ruby_executable_node(void *n, int *status)
       case Qtrue:  s = EXIT_SUCCESS; break;
       case Qfalse: s = EXIT_FAILURE; break;
       default:
-	if (!FIXNUM_P(v)) return TRUE;
-	s = FIX2INT(v);
+        if (!FIXNUM_P(v)) return TRUE;
+        s = FIX2INT(v);
     }
     if (status) *status = s;
     return FALSE;
@@ -314,8 +323,8 @@ ruby_run_node(void *n)
     rb_execution_context_t *ec = GET_EC();
     int status;
     if (!ruby_executable_node(n, &status)) {
-        rb_ec_cleanup(ec, 0);
-	return status;
+        rb_ec_cleanup(ec, (NIL_P(ec->errinfo) ? TAG_NONE : TAG_RAISE));
+        return status;
     }
     ruby_init_stack((void *)&status);
     return rb_ec_cleanup(ec, rb_ec_exec_node(ec, n));
@@ -350,12 +359,12 @@ rb_mod_nesting(VALUE _)
     const rb_cref_t *cref = rb_vm_cref();
 
     while (cref && CREF_NEXT(cref)) {
-	VALUE klass = CREF_CLASS(cref);
-	if (!CREF_PUSHED_BY_EVAL(cref) &&
-	    !NIL_P(klass)) {
-	    rb_ary_push(ary, klass);
-	}
-	cref = CREF_NEXT(cref);
+        VALUE klass = CREF_CLASS(cref);
+        if (!CREF_PUSHED_BY_EVAL(cref) &&
+            !NIL_P(klass)) {
+            rb_ary_push(ary, klass);
+        }
+        cref = CREF_NEXT(cref);
     }
     return ary;
 }
@@ -391,23 +400,23 @@ rb_mod_s_constants(int argc, VALUE *argv, VALUE mod)
     void *data = 0;
 
     if (argc > 0 || mod != rb_cModule) {
-	return rb_mod_constants(argc, argv, mod);
+        return rb_mod_constants(argc, argv, mod);
     }
 
     while (cref) {
-	klass = CREF_CLASS(cref);
-	if (!CREF_PUSHED_BY_EVAL(cref) &&
-	    !NIL_P(klass)) {
-	    data = rb_mod_const_at(CREF_CLASS(cref), data);
-	    if (!cbase) {
-		cbase = klass;
-	    }
-	}
-	cref = CREF_NEXT(cref);
+        klass = CREF_CLASS(cref);
+        if (!CREF_PUSHED_BY_EVAL(cref) &&
+            !NIL_P(klass)) {
+            data = rb_mod_const_at(CREF_CLASS(cref), data);
+            if (!cbase) {
+                cbase = klass;
+            }
+        }
+        cref = CREF_NEXT(cref);
     }
 
     if (cbase) {
-	data = rb_mod_const_of(cbase, data);
+        data = rb_mod_const_of(cbase, data);
     }
     return rb_const_list(data);
 }
@@ -422,45 +431,45 @@ void
 rb_class_modify_check(VALUE klass)
 {
     if (SPECIAL_CONST_P(klass)) {
-	Check_Type(klass, T_CLASS);
+        Check_Type(klass, T_CLASS);
     }
     if (RB_TYPE_P(klass, T_MODULE)) {
         rb_module_set_initialized(klass);
     }
     if (OBJ_FROZEN(klass)) {
-	const char *desc;
-
-	if (FL_TEST(klass, FL_SINGLETON)) {
-	    desc = "object";
-	    klass = rb_ivar_get(klass, id__attached__);
-	    if (!SPECIAL_CONST_P(klass)) {
-		switch (BUILTIN_TYPE(klass)) {
-		  case T_MODULE:
-		  case T_ICLASS:
-		    desc = "Module";
-		    break;
-		  case T_CLASS:
-		    desc = "Class";
-		    break;
+        const char *desc;
+
+        if (FL_TEST(klass, FL_SINGLETON)) {
+            desc = "object";
+            klass = rb_ivar_get(klass, id__attached__);
+            if (!SPECIAL_CONST_P(klass)) {
+                switch (BUILTIN_TYPE(klass)) {
+                  case T_MODULE:
+                  case T_ICLASS:
+                    desc = "Module";
+                    break;
+                  case T_CLASS:
+                    desc = "Class";
+                    break;
                   default:
                     break;
-		}
-	    }
-	}
-	else {
-	    switch (BUILTIN_TYPE(klass)) {
-	      case T_MODULE:
-	      case T_ICLASS:
-		desc = "module";
-		break;
-	      case T_CLASS:
-		desc = "class";
-		break;
-	      default:
+                }
+            }
+        }
+        else {
+            switch (BUILTIN_TYPE(klass)) {
+              case T_MODULE:
+              case T_ICLASS:
+                desc = "module";
+                break;
+              case T_CLASS:
+                desc = "class";
+                break;
+              default:
                 Check_Type(klass, T_CLASS);
                 UNREACHABLE;
-	    }
-	}
+            }
+        }
         rb_frozen_error_raise(klass, "can't modify frozen %s: %"PRIsVALUE, desc, klass);
     }
 }
@@ -474,23 +483,23 @@ exc_setup_cause(VALUE exc, VALUE cause)
 {
 #if OPT_SUPPORT_JOKE
     if (NIL_P(cause)) {
-	ID id_true_cause;
-	CONST_ID(id_true_cause, "true_cause");
-
-	cause = rb_attr_get(rb_eFatal, id_true_cause);
-	if (NIL_P(cause)) {
-	    cause = rb_exc_new_cstr(rb_eFatal, "because using such Ruby");
-	    rb_ivar_set(cause, id_cause, INT2FIX(42)); /* the answer */
-	    OBJ_FREEZE(cause);
-	    rb_ivar_set(rb_eFatal, id_true_cause, cause);
-	}
+        ID id_true_cause;
+        CONST_ID(id_true_cause, "true_cause");
+
+        cause = rb_attr_get(rb_eFatal, id_true_cause);
+        if (NIL_P(cause)) {
+            cause = rb_exc_new_cstr(rb_eFatal, "because using such Ruby");
+            rb_ivar_set(cause, id_cause, INT2FIX(42)); /* the answer */
+            OBJ_FREEZE(cause);
+            rb_ivar_set(rb_eFatal, id_true_cause, cause);
+        }
     }
 #endif
     if (!NIL_P(cause) && cause != exc) {
-	rb_ivar_set(exc, id_cause, cause);
-	if (!rb_ivar_defined(cause, id_cause)) {
-	    rb_ivar_set(cause, id_cause, Qnil);
-	}
+        rb_ivar_set(exc, id_cause, cause);
+        if (!rb_ivar_defined(cause, id_cause)) {
+            rb_ivar_set(cause, id_cause, Qnil);
+        }
     }
     return exc;
 }
@@ -502,23 +511,23 @@ exc_setup_message(const rb_execution_context_t *ec, VALUE mesg, VALUE *cause)
     int nocircular = 0;
 
     if (NIL_P(mesg)) {
-	mesg = ec->errinfo;
-	if (INTERNAL_EXCEPTION_P(mesg)) EC_JUMP_TAG(ec, TAG_FATAL);
-	nocause = 1;
+        mesg = ec->errinfo;
+        if (INTERNAL_EXCEPTION_P(mesg)) EC_JUMP_TAG(ec, TAG_FATAL);
+        nocause = 1;
     }
     if (NIL_P(mesg)) {
-	mesg = rb_exc_new(rb_eRuntimeError, 0, 0);
-	nocause = 0;
+        mesg = rb_exc_new(rb_eRuntimeError, 0, 0);
+        nocause = 0;
         nocircular = 1;
     }
-    if (*cause == Qundef) {
-	if (nocause) {
-	    *cause = Qnil;
+    if (UNDEF_P(*cause)) {
+        if (nocause) {
+            *cause = Qnil;
             nocircular = 1;
-	}
-	else if (!rb_ivar_defined(mesg, id_cause)) {
-	    *cause = get_ec_errinfo(ec);
-	}
+        }
+        else if (!rb_ivar_defined(mesg, id_cause)) {
+            *cause = get_ec_errinfo(ec);
+        }
         else {
             nocircular = 1;
         }
@@ -527,13 +536,17 @@ exc_setup_message(const rb_execution_context_t *ec, VALUE mesg, VALUE *cause)
         rb_raise(rb_eTypeError, "exception object expected");
     }
 
-    if (!nocircular && !NIL_P(*cause) && *cause != Qundef && *cause != mesg) {
+    if (!nocircular && !NIL_P(*cause) && !UNDEF_P(*cause) && *cause != mesg) {
+#if 0 /* maybe critical for some cases */
+        rb_exc_check_circular_cause(*cause);
+#else
         VALUE c = *cause;
         while (!NIL_P(c = rb_attr_get(c, id_cause))) {
             if (c == mesg) {
                 rb_raise(rb_eArgError, "circular causes");
             }
         }
+#endif
     }
     return mesg;
 }
@@ -546,68 +559,68 @@ setup_exception(rb_execution_context_t *ec, int tag, volatile VALUE mesg, VALUE
     const char *file = rb_source_location_cstr(&line);
     const char *const volatile file0 = file;
 
-    if ((file && !NIL_P(mesg)) || (cause != Qundef))  {
-	volatile int state = 0;
-
-	EC_PUSH_TAG(ec);
-	if (EC_EXEC_TAG() == TAG_NONE && !(state = rb_ec_set_raised(ec))) {
-	    VALUE bt = rb_get_backtrace(mesg);
-	    if (!NIL_P(bt) || cause == Qundef) {
-		if (OBJ_FROZEN(mesg)) {
-		    mesg = rb_obj_dup(mesg);
-		}
-	    }
-            if (cause != Qundef && !THROW_DATA_P(cause)) {
-		exc_setup_cause(mesg, cause);
-	    }
-	    if (NIL_P(bt)) {
-		VALUE at = rb_ec_backtrace_object(ec);
-		rb_ivar_set(mesg, idBt_locations, at);
-		set_backtrace(mesg, at);
-	    }
-	    rb_ec_reset_raised(ec);
-	}
-	EC_POP_TAG();
+    if ((file && !NIL_P(mesg)) || !UNDEF_P(cause))  {
+        volatile int state = 0;
+
+        EC_PUSH_TAG(ec);
+        if (EC_EXEC_TAG() == TAG_NONE && !(state = rb_ec_set_raised(ec))) {
+            VALUE bt = rb_get_backtrace(mesg);
+            if (!NIL_P(bt) || UNDEF_P(cause)) {
+                if (OBJ_FROZEN(mesg)) {
+                    mesg = rb_obj_dup(mesg);
+                }
+            }
+            if (!UNDEF_P(cause) && !THROW_DATA_P(cause)) {
+                exc_setup_cause(mesg, cause);
+            }
+            if (NIL_P(bt)) {
+                VALUE at = rb_ec_backtrace_object(ec);
+                rb_ivar_set(mesg, idBt_locations, at);
+                set_backtrace(mesg, at);
+            }
+            rb_ec_reset_raised(ec);
+        }
+        EC_POP_TAG();
         file = file0;
-	if (state) goto fatal;
+        if (state) goto fatal;
     }
 
     if (!NIL_P(mesg)) {
-	ec->errinfo = mesg;
+        ec->errinfo = mesg;
     }
 
     if (RTEST(ruby_debug) && !NIL_P(e = ec->errinfo) &&
-	!rb_obj_is_kind_of(e, rb_eSystemExit)) {
-	enum ruby_tag_type state;
-
-	mesg = e;
-	EC_PUSH_TAG(ec);
-	if ((state = EC_EXEC_TAG()) == TAG_NONE) {
-	    ec->errinfo = Qnil;
-	    e = rb_obj_as_string(mesg);
-	    ec->errinfo = mesg;
-	    if (file && line) {
-		e = rb_sprintf("Exception `%"PRIsVALUE"' at %s:%d - %"PRIsVALUE"\n",
-			       rb_obj_class(mesg), file, line, e);
-	    }
-	    else if (file) {
-		e = rb_sprintf("Exception `%"PRIsVALUE"' at %s - %"PRIsVALUE"\n",
-			       rb_obj_class(mesg), file, e);
-	    }
-	    else {
-		e = rb_sprintf("Exception `%"PRIsVALUE"' - %"PRIsVALUE"\n",
-			       rb_obj_class(mesg), e);
-	    }
-	    warn_print_str(e);
-	}
-	EC_POP_TAG();
-	if (state == TAG_FATAL && ec->errinfo == exception_error) {
-	    ec->errinfo = mesg;
-	}
-	else if (state) {
-	    rb_ec_reset_raised(ec);
-	    EC_JUMP_TAG(ec, state);
-	}
+        !rb_obj_is_kind_of(e, rb_eSystemExit)) {
+        enum ruby_tag_type state;
+
+        mesg = e;
+        EC_PUSH_TAG(ec);
+        if ((state = EC_EXEC_TAG()) == TAG_NONE) {
+            ec->errinfo = Qnil;
+            e = rb_obj_as_string(mesg);
+            ec->errinfo = mesg;
+            if (file && line) {
+                e = rb_sprintf("Exception `%"PRIsVALUE"' at %s:%d - %"PRIsVALUE"\n",
+                               rb_obj_class(mesg), file, line, e);
+            }
+            else if (file) {
+                e = rb_sprintf("Exception `%"PRIsVALUE"' at %s - %"PRIsVALUE"\n",
+                               rb_obj_class(mesg), file, e);
+            }
+            else {
+                e = rb_sprintf("Exception `%"PRIsVALUE"' - %"PRIsVALUE"\n",
+                               rb_obj_class(mesg), e);
+            }
+            warn_print_str(e);
+        }
+        EC_POP_TAG();
+        if (state == TAG_FATAL && ec->errinfo == exception_error) {
+            ec->errinfo = mesg;
+        }
+        else if (state) {
+            rb_ec_reset_raised(ec);
+            EC_JUMP_TAG(ec, state);
+        }
     }
 
     if (rb_ec_set_raised(ec)) {
@@ -615,8 +628,8 @@ setup_exception(rb_execution_context_t *ec, int tag, volatile VALUE mesg, VALUE
     }
 
     if (tag != TAG_FATAL) {
-	RUBY_DTRACE_HOOK(RAISE, rb_obj_classname(ec->errinfo));
-	EXEC_EVENT_HOOK(ec, RUBY_EVENT_RAISE, ec->cfp->self, 0, 0, 0, mesg);
+        RUBY_DTRACE_HOOK(RAISE, rb_obj_classname(ec->errinfo));
+        EXEC_EVENT_HOOK(ec, RUBY_EVENT_RAISE, ec->cfp->self, 0, 0, 0, mesg);
     }
     return;
 
@@ -630,11 +643,15 @@ setup_exception(rb_execution_context_t *ec, int tag, volatile VALUE mesg, VALUE
 void
 rb_ec_setup_exception(const rb_execution_context_t *ec, VALUE mesg, VALUE cause)
 {
-    if (cause == Qundef) {
-	cause = get_ec_errinfo(ec);
+    if (UNDEF_P(cause)) {
+        cause = get_ec_errinfo(ec);
     }
     if (cause != mesg) {
-	rb_ivar_set(mesg, id_cause, cause);
+        if (THROW_DATA_P(cause)) {
+            cause = Qnil;
+        }
+
+        rb_ivar_set(mesg, id_cause, cause);
     }
 }
 
@@ -655,7 +672,7 @@ static void
 rb_exc_exception(VALUE mesg, int tag, VALUE cause)
 {
     if (!NIL_P(mesg)) {
-	mesg = make_exception(1, &mesg, FALSE);
+        mesg = make_exception(1, &mesg, FALSE);
     }
     rb_longjmp(GET_EC(), tag, mesg, cause);
 }
@@ -699,20 +716,20 @@ extract_raise_opts(int argc, VALUE *argv, VALUE *opts)
 {
     int i;
     if (argc > 0) {
-	VALUE opt;
-	argc = rb_scan_args(argc, argv, "*:", NULL, &opt);
-	if (!NIL_P(opt)) {
-	    if (!RHASH_EMPTY_P(opt)) {
-		ID keywords[1];
-		CONST_ID(keywords[0], "cause");
-		rb_get_kwargs(opt, keywords, 0, -1-raise_max_opt, opts);
-		if (!RHASH_EMPTY_P(opt)) argv[argc++] = opt;
-		return argc;
-	    }
-	}
+        VALUE opt;
+        argc = rb_scan_args(argc, argv, "*:", NULL, &opt);
+        if (!NIL_P(opt)) {
+            if (!RHASH_EMPTY_P(opt)) {
+                ID keywords[1];
+                CONST_ID(keywords[0], "cause");
+                rb_get_kwargs(opt, keywords, 0, -1-raise_max_opt, opts);
+                if (!RHASH_EMPTY_P(opt)) argv[argc++] = opt;
+                return argc;
+            }
+        }
     }
     for (i = 0; i < raise_max_opt; ++i) {
-	opts[i] = Qundef;
+        opts[i] = Qundef;
     }
     return argc;
 }
@@ -725,7 +742,7 @@ rb_f_raise(int argc, VALUE *argv)
 
     argc = extract_raise_opts(argc, argv, opts);
     if (argc == 0) {
-        if (*cause != Qundef) {
+        if (!UNDEF_P(*cause)) {
             rb_raise(rb_eArgError, "only cause is given with no arguments");
         }
         err = get_errinfo();
@@ -784,24 +801,24 @@ make_exception(int argc, const VALUE *argv, int isstr)
       case 0:
         return Qnil;
       case 1:
-	exc = argv[0];
+        exc = argv[0];
         if (isstr &&! NIL_P(exc)) {
-	    mesg = rb_check_string_type(exc);
-	    if (!NIL_P(mesg)) {
+            mesg = rb_check_string_type(exc);
+            if (!NIL_P(mesg)) {
                 return rb_exc_new3(rb_eRuntimeError, mesg);
-	    }
-	}
+            }
+        }
 
       case 2:
       case 3:
-	break;
+        break;
       default:
         rb_error_arity(argc, 0, 3);
     }
     if (NIL_P(mesg)) {
         mesg = rb_check_funcall(argv[0], idException, argc != 1, &argv[1]);
     }
-    if (mesg == Qundef) {
+    if (UNDEF_P(mesg)) {
         rb_raise(rb_eTypeError, "exception class/object expected");
     }
     if (!rb_obj_is_kind_of(mesg, rb_eException)) {
@@ -842,7 +859,7 @@ void
 rb_jump_tag(int tag)
 {
     if (UNLIKELY(tag < TAG_RETURN || tag > TAG_FATAL)) {
-	unknown_longjmp_status(tag);
+        unknown_longjmp_status(tag);
     }
     EC_JUMP_TAG(GET_EC(), tag);
 }
@@ -851,10 +868,10 @@ int
 rb_block_given_p(void)
 {
     if (rb_vm_frame_block_handler(GET_EC()->cfp) == VM_BLOCK_HANDLER_NONE) {
-	return FALSE;
+        return FALSE;
     }
     else {
-	return TRUE;
+        return TRUE;
     }
 }
 
@@ -872,7 +889,7 @@ void
 rb_need_block(void)
 {
     if (!rb_block_given_p()) {
-	rb_vm_localjump_error("no block given", Qnil, 0);
+        rb_vm_localjump_error("no block given", Qnil, 0);
     }
 }
 
@@ -901,48 +918,48 @@ rb_vrescue2(VALUE (* b_proc) (VALUE), VALUE data1,
     EC_PUSH_TAG(ec);
     if ((state = EC_EXEC_TAG()) == TAG_NONE) {
       retry_entry:
-	result = (*b_proc) (data1);
+        result = (*b_proc) (data1);
     }
     else if (result) {
-	/* escape from r_proc */
-	if (state == TAG_RETRY) {
-	    state = TAG_NONE;
-	    ec->errinfo = Qnil;
-	    result = Qfalse;
-	    goto retry_entry;
-	}
+        /* escape from r_proc */
+        if (state == TAG_RETRY) {
+            state = TAG_NONE;
+            ec->errinfo = Qnil;
+            result = Qfalse;
+            goto retry_entry;
+        }
     }
     else {
-	rb_vm_rewind_cfp(ec, cfp);
-
-	if (state == TAG_RAISE) {
-	    int handle = FALSE;
-	    VALUE eclass;
-	    va_list ap;
-
-	    result = Qnil;
-	    /* reuses args when raised again after retrying in r_proc */
-	    va_copy(ap, args);
-	    while ((eclass = va_arg(ap, VALUE)) != 0) {
-		if (rb_obj_is_kind_of(ec->errinfo, eclass)) {
-		    handle = TRUE;
-		    break;
-		}
-	    }
-	    va_end(ap);
-
-	    if (handle) {
-		state = TAG_NONE;
-		if (r_proc) {
-		    result = (*r_proc) (data2, ec->errinfo);
-		}
-		ec->errinfo = e_info;
-	    }
-	}
+        rb_vm_rewind_cfp(ec, cfp);
+
+        if (state == TAG_RAISE) {
+            int handle = FALSE;
+            VALUE eclass;
+            va_list ap;
+
+            result = Qnil;
+            /* reuses args when raised again after retrying in r_proc */
+            va_copy(ap, args);
+            while ((eclass = va_arg(ap, VALUE)) != 0) {
+                if (rb_obj_is_kind_of(ec->errinfo, eclass)) {
+                    handle = TRUE;
+                    break;
+                }
+            }
+            va_end(ap);
+
+            if (handle) {
+                state = TAG_NONE;
+                if (r_proc) {
+                    result = (*r_proc) (data2, ec->errinfo);
+                }
+                ec->errinfo = e_info;
+            }
+        }
     }
     EC_POP_TAG();
     if (state)
-	EC_JUMP_TAG(ec, state);
+        EC_JUMP_TAG(ec, state);
 
     return result;
 }
@@ -952,7 +969,7 @@ rb_rescue(VALUE (* b_proc)(VALUE), VALUE data1,
           VALUE (* r_proc)(VALUE, VALUE), VALUE data2)
 {
     return rb_rescue2(b_proc, data1, r_proc, data2, rb_eStandardError,
-		      (VALUE)0);
+                      (VALUE)0);
 }
 
 VALUE
@@ -965,10 +982,10 @@ rb_protect(VALUE (* proc) (VALUE), VALUE data, int *pstate)
 
     EC_PUSH_TAG(ec);
     if ((state = EC_EXEC_TAG()) == TAG_NONE) {
-	SAVE_ROOT_JMPBUF(rb_ec_thread_ptr(ec), result = (*proc) (data));
+        SAVE_ROOT_JMPBUF(rb_ec_thread_ptr(ec), result = (*proc) (data));
     }
     else {
-	rb_vm_rewind_cfp(ec, cfp);
+        rb_vm_rewind_cfp(ec, cfp);
     }
     EC_POP_TAG();
 
@@ -991,18 +1008,18 @@ rb_ensure(VALUE (*b_proc)(VALUE), VALUE data1, VALUE (*e_proc)(VALUE), VALUE dat
     ec->ensure_list = &ensure_list;
     EC_PUSH_TAG(ec);
     if ((state = EC_EXEC_TAG()) == TAG_NONE) {
-	result = (*b_proc) (data1);
+        result = (*b_proc) (data1);
     }
     EC_POP_TAG();
     errinfo = ec->errinfo;
     if (!NIL_P(errinfo) && !RB_TYPE_P(errinfo, T_OBJECT)) {
-	ec->errinfo = Qnil;
+        ec->errinfo = Qnil;
     }
     ec->ensure_list=ensure_list.next;
     (*ensure_list.entry.e_proc)(ensure_list.entry.data2);
     ec->errinfo = errinfo;
     if (state)
-	EC_JUMP_TAG(ec, state);
+        EC_JUMP_TAG(ec, state);
     return result;
 }
 
@@ -1012,10 +1029,10 @@ frame_func_id(const rb_control_frame_t *cfp)
     const rb_callable_method_entry_t *me = rb_vm_frame_method_entry(cfp);
 
     if (me) {
-	return me->def->original_id;
+        return me->def->original_id;
     }
     else {
-	return 0;
+        return 0;
     }
 }
 
@@ -1025,10 +1042,10 @@ frame_called_id(rb_control_frame_t *cfp)
     const rb_callable_method_entry_t *me = rb_vm_frame_method_entry(cfp);
 
     if (me) {
-	return me->called_id;
+        return me->called_id;
     }
     else {
-	return 0;
+        return 0;
     }
 }
 
@@ -1085,8 +1102,8 @@ rb_frame_last_func(void)
     ID mid;
 
     while (!(mid = frame_func_id(cfp)) &&
-	   (cfp = RUBY_VM_PREVIOUS_CONTROL_FRAME(cfp),
-	    !RUBY_VM_CONTROL_FRAME_STACK_OVERFLOW_P(ec, cfp)));
+           (cfp = RUBY_VM_PREVIOUS_CONTROL_FRAME(cfp),
+            !RUBY_VM_CONTROL_FRAME_STACK_OVERFLOW_P(ec, cfp)));
     return mid;
 }
 
@@ -1106,7 +1123,7 @@ static VALUE
 rb_mod_append_features(VALUE module, VALUE include)
 {
     if (!CLASS_OR_MODULE_P(include)) {
-	Check_Type(include, T_CLASS);
+        Check_Type(include, T_CLASS);
     }
     rb_include_module(include, module);
 
@@ -1129,20 +1146,20 @@ rb_mod_include(int argc, VALUE *argv, VALUE module)
     CONST_ID(id_append_features, "append_features");
     CONST_ID(id_included, "included");
 
-    if (FL_TEST(module, RMODULE_IS_REFINEMENT)) {
+    if (BUILTIN_TYPE(module) == T_MODULE && FL_TEST(module, RMODULE_IS_REFINEMENT)) {
         rb_raise(rb_eTypeError, "Refinement#include has been removed");
     }
 
     rb_check_arity(argc, 1, UNLIMITED_ARGUMENTS);
     for (i = 0; i < argc; i++) {
-	Check_Type(argv[i], T_MODULE);
+        Check_Type(argv[i], T_MODULE);
         if (FL_TEST(argv[i], RMODULE_IS_REFINEMENT)) {
             rb_raise(rb_eTypeError, "Cannot include refinement");
         }
     }
     while (argc--) {
-	rb_funcall(argv[argc], id_append_features, 1, module);
-	rb_funcall(argv[argc], id_included, 1, module);
+        rb_funcall(argv[argc], id_append_features, 1, module);
+        rb_funcall(argv[argc], id_included, 1, module);
     }
     return module;
 }
@@ -1163,7 +1180,7 @@ static VALUE
 rb_mod_prepend_features(VALUE module, VALUE prepend)
 {
     if (!CLASS_OR_MODULE_P(prepend)) {
-	Check_Type(prepend, T_CLASS);
+        Check_Type(prepend, T_CLASS);
     }
     rb_prepend_module(prepend, module);
 
@@ -1183,7 +1200,7 @@ rb_mod_prepend(int argc, VALUE *argv, VALUE module)
     int i;
     ID id_prepend_features, id_prepended;
 
-    if (FL_TEST(module, RMODULE_IS_REFINEMENT)) {
+    if (BUILTIN_TYPE(module) == T_MODULE && FL_TEST(module, RMODULE_IS_REFINEMENT)) {
         rb_raise(rb_eTypeError, "Refinement#prepend has been removed");
     }
 
@@ -1192,14 +1209,14 @@ rb_mod_prepend(int argc, VALUE *argv, VALUE module)
 
     rb_check_arity(argc, 1, UNLIMITED_ARGUMENTS);
     for (i = 0; i < argc; i++) {
-	Check_Type(argv[i], T_MODULE);
+        Check_Type(argv[i], T_MODULE);
         if (FL_TEST(argv[i], RMODULE_IS_REFINEMENT)) {
             rb_raise(rb_eTypeError, "Cannot prepend refinement");
         }
     }
     while (argc--) {
-	rb_funcall(argv[argc], id_prepend_features, 1, module);
-	rb_funcall(argv[argc], id_prepended, 1, module);
+        rb_funcall(argv[argc], id_prepend_features, 1, module);
+        rb_funcall(argv[argc], id_prepended, 1, module);
     }
     return module;
 }
@@ -1208,9 +1225,9 @@ static void
 ensure_class_or_module(VALUE obj)
 {
     if (!RB_TYPE_P(obj, T_CLASS) && !RB_TYPE_P(obj, T_MODULE)) {
-	rb_raise(rb_eTypeError,
-		 "wrong argument type %"PRIsVALUE" (expected Class or Module)",
-		 rb_obj_class(obj));
+        rb_raise(rb_eTypeError,
+                 "wrong argument type %"PRIsVALUE" (expected Class or Module)",
+                 rb_obj_class(obj));
     }
 }
 
@@ -1227,11 +1244,11 @@ static VALUE
 refinement_superclass(VALUE superclass)
 {
     if (RB_TYPE_P(superclass, T_MODULE)) {
-	/* FIXME: Should ancestors of superclass be used here? */
+        /* FIXME: Should ancestors of superclass be used here? */
         return rb_include_class_new(RCLASS_ORIGIN(superclass), rb_cBasicObject);
     }
     else {
-	return superclass;
+        return superclass;
     }
 }
 
@@ -1246,25 +1263,24 @@ rb_using_refinement(rb_cref_t *cref, VALUE klass, VALUE module)
     ensure_class_or_module(klass);
     Check_Type(module, T_MODULE);
     if (NIL_P(CREF_REFINEMENTS(cref))) {
-	CREF_REFINEMENTS_SET(cref, hidden_identity_hash_new());
+        CREF_REFINEMENTS_SET(cref, hidden_identity_hash_new());
     }
     else {
-	if (CREF_OMOD_SHARED(cref)) {
-	    CREF_REFINEMENTS_SET(cref, rb_hash_dup(CREF_REFINEMENTS(cref)));
-	    CREF_OMOD_SHARED_UNSET(cref);
-	}
-	if (!NIL_P(c = rb_hash_lookup(CREF_REFINEMENTS(cref), klass))) {
-	    superclass = c;
-	    while (c && RB_TYPE_P(c, T_ICLASS)) {
-		if (RBASIC(c)->klass == module) {
-		    /* already used refinement */
-		    return;
-		}
-		c = RCLASS_SUPER(c);
-	    }
-	}
-    }
-    FL_SET(module, RMODULE_IS_OVERLAID);
+        if (CREF_OMOD_SHARED(cref)) {
+            CREF_REFINEMENTS_SET(cref, rb_hash_dup(CREF_REFINEMENTS(cref)));
+            CREF_OMOD_SHARED_UNSET(cref);
+        }
+        if (!NIL_P(c = rb_hash_lookup(CREF_REFINEMENTS(cref), klass))) {
+            superclass = c;
+            while (c && RB_TYPE_P(c, T_ICLASS)) {
+                if (RBASIC(c)->klass == module) {
+                    /* already used refinement */
+                    return;
+                }
+                c = RCLASS_SUPER(c);
+            }
+        }
+    }
     superclass = refinement_superclass(superclass);
     c = iclass = rb_include_class_new(module, superclass);
     RB_OBJ_WRITE(c, &RCLASS_REFINED_CLASS(c), klass);
@@ -1273,8 +1289,7 @@ rb_using_refinement(rb_cref_t *cref, VALUE klass, VALUE module)
 
     module = RCLASS_SUPER(module);
     while (module && module != klass) {
-	FL_SET(module, RMODULE_IS_OVERLAID);
-	c = RCLASS_SET_SUPER(c, rb_include_class_new(module, RCLASS_SUPER(c)));
+        c = RCLASS_SET_SUPER(c, rb_include_class_new(module, RCLASS_SUPER(c)));
         RB_OBJ_WRITE(c, &RCLASS_REFINED_CLASS(c), klass);
         module = RCLASS_SUPER(module);
     }
@@ -1298,21 +1313,21 @@ using_module_recursive(const rb_cref_t *cref, VALUE klass)
 
     super = RCLASS_SUPER(klass);
     if (super) {
-	using_module_recursive(cref, super);
+        using_module_recursive(cref, super);
     }
     switch (BUILTIN_TYPE(klass)) {
       case T_MODULE:
-	module = klass;
-	break;
+        module = klass;
+        break;
 
       case T_ICLASS:
-	module = RBASIC(klass)->klass;
-	break;
+        module = RBASIC(klass)->klass;
+        break;
 
       default:
-	rb_raise(rb_eTypeError, "wrong argument type %s (expected Module)",
-		 rb_obj_classname(klass));
-	break;
+        rb_raise(rb_eTypeError, "wrong argument type %s (expected Module)",
+                 rb_obj_classname(klass));
+        break;
     }
     CONST_ID(id_refinements, "__refinements__");
     refinements = rb_attr_get(module, id_refinements);
@@ -1348,30 +1363,28 @@ rb_refinement_module_get_refined_class(VALUE module)
 
 static void
 add_activated_refinement(VALUE activated_refinements,
-			 VALUE klass, VALUE refinement)
+                         VALUE klass, VALUE refinement)
 {
     VALUE iclass, c, superclass = klass;
 
     if (!NIL_P(c = rb_hash_lookup(activated_refinements, klass))) {
-	superclass = c;
-	while (c && RB_TYPE_P(c, T_ICLASS)) {
-	    if (RBASIC(c)->klass == refinement) {
-		/* already used refinement */
-		return;
-	    }
-	    c = RCLASS_SUPER(c);
-	}
-    }
-    FL_SET(refinement, RMODULE_IS_OVERLAID);
+        superclass = c;
+        while (c && RB_TYPE_P(c, T_ICLASS)) {
+            if (RBASIC(c)->klass == refinement) {
+                /* already used refinement */
+                return;
+            }
+            c = RCLASS_SUPER(c);
+        }
+    }
     superclass = refinement_superclass(superclass);
     c = iclass = rb_include_class_new(refinement, superclass);
     RB_OBJ_WRITE(c, &RCLASS_REFINED_CLASS(c), klass);
     refinement = RCLASS_SUPER(refinement);
     while (refinement && refinement != klass) {
-	FL_SET(refinement, RMODULE_IS_OVERLAID);
-	c = RCLASS_SET_SUPER(c, rb_include_class_new(refinement, RCLASS_SUPER(c)));
+        c = RCLASS_SET_SUPER(c, rb_include_class_new(refinement, RCLASS_SUPER(c)));
         RB_OBJ_WRITE(c, &RCLASS_REFINED_CLASS(c), klass);
-	refinement = RCLASS_SUPER(refinement);
+        refinement = RCLASS_SUPER(refinement);
     }
     rb_hash_aset(activated_refinements, klass, iclass);
 }
@@ -1396,38 +1409,39 @@ rb_mod_refine(VALUE module, VALUE klass)
     VALUE block_handler = rb_vm_frame_block_handler(th->ec->cfp);
 
     if (block_handler == VM_BLOCK_HANDLER_NONE) {
-	rb_raise(rb_eArgError, "no block given");
+        rb_raise(rb_eArgError, "no block given");
     }
     if (vm_block_handler_type(block_handler) != block_handler_type_iseq) {
-	rb_raise(rb_eArgError, "can't pass a Proc as a block to Module#refine");
+        rb_raise(rb_eArgError, "can't pass a Proc as a block to Module#refine");
     }
 
     ensure_class_or_module(klass);
     CONST_ID(id_refinements, "__refinements__");
     refinements = rb_attr_get(module, id_refinements);
     if (NIL_P(refinements)) {
-	refinements = hidden_identity_hash_new();
-	rb_ivar_set(module, id_refinements, refinements);
+        refinements = hidden_identity_hash_new();
+        rb_ivar_set(module, id_refinements, refinements);
     }
     CONST_ID(id_activated_refinements, "__activated_refinements__");
     activated_refinements = rb_attr_get(module, id_activated_refinements);
     if (NIL_P(activated_refinements)) {
-	activated_refinements = hidden_identity_hash_new();
-	rb_ivar_set(module, id_activated_refinements,
-		    activated_refinements);
+        activated_refinements = hidden_identity_hash_new();
+        rb_ivar_set(module, id_activated_refinements,
+                    activated_refinements);
     }
     refinement = rb_hash_lookup(refinements, klass);
     if (NIL_P(refinement)) {
-	VALUE superclass = refinement_superclass(klass);
-	refinement = rb_refinement_new();
-	RCLASS_SET_SUPER(refinement, superclass);
-	FL_SET(refinement, RMODULE_IS_REFINEMENT);
-	CONST_ID(id_refined_class, "__refined_class__");
-	rb_ivar_set(refinement, id_refined_class, klass);
-	CONST_ID(id_defined_at, "__defined_at__");
-	rb_ivar_set(refinement, id_defined_at, module);
-	rb_hash_aset(refinements, klass, refinement);
-	add_activated_refinement(activated_refinements, klass, refinement);
+        VALUE superclass = refinement_superclass(klass);
+        refinement = rb_refinement_new();
+        RCLASS_SET_SUPER(refinement, superclass);
+        RUBY_ASSERT(BUILTIN_TYPE(refinement) == T_MODULE);
+        FL_SET(refinement, RMODULE_IS_REFINEMENT);
+        CONST_ID(id_refined_class, "__refined_class__");
+        rb_ivar_set(refinement, id_refined_class, klass);
+        CONST_ID(id_defined_at, "__defined_at__");
+        rb_ivar_set(refinement, id_defined_at, module);
+        rb_hash_aset(refinements, klass, refinement);
+        add_activated_refinement(activated_refinements, klass, refinement);
     }
     rb_yield_refine_block(refinement, activated_refinements);
     return refinement;
@@ -1439,7 +1453,7 @@ ignored_block(VALUE module, const char *klass)
     const char *anon = "";
     Check_Type(module, T_MODULE);
     if (!RTEST(rb_search_class_path(module))) {
-	anon = ", maybe for Module.new";
+        anon = ", maybe for Module.new";
     }
     rb_warn("%s""using doesn't call the given block""%s.", klass, anon);
 }
@@ -1458,14 +1472,14 @@ mod_using(VALUE self, VALUE module)
     rb_control_frame_t *prev_cfp = previous_frame(GET_EC());
 
     if (prev_frame_func()) {
-	rb_raise(rb_eRuntimeError,
-		 "Module#using is not permitted in methods");
+        rb_raise(rb_eRuntimeError,
+                 "Module#using is not permitted in methods");
     }
     if (prev_cfp && prev_cfp->self != self) {
-	rb_raise(rb_eRuntimeError, "Module#using is not called on self");
+        rb_raise(rb_eRuntimeError, "Module#using is not called on self");
     }
     if (rb_block_given_p()) {
-	ignored_block(module, "Module#");
+        ignored_block(module, "Module#");
     }
     rb_using_module(rb_vm_cref_replace_with_duplicated_cref(), module);
     return self;
@@ -1511,9 +1525,9 @@ used_modules_i(VALUE _, VALUE mod, VALUE ary)
 {
     ID id_defined_at;
     CONST_ID(id_defined_at, "__defined_at__");
-    while (FL_TEST(rb_class_of(mod), RMODULE_IS_REFINEMENT)) {
-	rb_ary_push(ary, rb_attr_get(rb_class_of(mod), id_defined_at));
-	mod = RCLASS_SUPER(mod);
+    while (BUILTIN_TYPE(rb_class_of(mod)) == T_MODULE && FL_TEST(rb_class_of(mod), RMODULE_IS_REFINEMENT)) {
+        rb_ary_push(ary, rb_attr_get(rb_class_of(mod), id_defined_at));
+        mod = RCLASS_SUPER(mod);
     }
     return ST_CONTINUE;
 }
@@ -1550,10 +1564,10 @@ rb_mod_s_used_modules(VALUE _)
     VALUE ary = rb_ary_new();
 
     while (cref) {
-	if (!NIL_P(CREF_REFINEMENTS(cref))) {
-	    rb_hash_foreach(CREF_REFINEMENTS(cref), used_modules_i, ary);
-	}
-	cref = CREF_NEXT(cref);
+        if (!NIL_P(CREF_REFINEMENTS(cref))) {
+            rb_hash_foreach(CREF_REFINEMENTS(cref), used_modules_i, ary);
+        }
+        cref = CREF_NEXT(cref);
     }
 
     return rb_funcall(ary, rb_intern("uniq"), 0);
@@ -1562,9 +1576,9 @@ rb_mod_s_used_modules(VALUE _)
 static int
 used_refinements_i(VALUE _, VALUE mod, VALUE ary)
 {
-    while (FL_TEST(rb_class_of(mod), RMODULE_IS_REFINEMENT)) {
+    while (BUILTIN_TYPE(rb_class_of(mod)) == T_MODULE && FL_TEST(rb_class_of(mod), RMODULE_IS_REFINEMENT)) {
         rb_ary_push(ary, rb_class_of(mod));
-	mod = RCLASS_SUPER(mod);
+        mod = RCLASS_SUPER(mod);
     }
     return ST_CONTINUE;
 }
@@ -1601,10 +1615,10 @@ rb_mod_s_used_refinements(VALUE _)
     VALUE ary = rb_ary_new();
 
     while (cref) {
-	if (!NIL_P(CREF_REFINEMENTS(cref))) {
-	    rb_hash_foreach(CREF_REFINEMENTS(cref), used_refinements_i, ary);
-	}
-	cref = CREF_NEXT(cref);
+        if (!NIL_P(CREF_REFINEMENTS(cref))) {
+            rb_hash_foreach(CREF_REFINEMENTS(cref), used_refinements_i, ary);
+        }
+        cref = CREF_NEXT(cref);
     }
 
     return ary;
@@ -1751,18 +1765,28 @@ rb_obj_extend(int argc, VALUE *argv, VALUE obj)
 
     rb_check_arity(argc, 1, UNLIMITED_ARGUMENTS);
     for (i = 0; i < argc; i++) {
-	Check_Type(argv[i], T_MODULE);
+        Check_Type(argv[i], T_MODULE);
         if (FL_TEST(argv[i], RMODULE_IS_REFINEMENT)) {
             rb_raise(rb_eTypeError, "Cannot extend object with refinement");
         }
     }
     while (argc--) {
-	rb_funcall(argv[argc], id_extend_object, 1, obj);
-	rb_funcall(argv[argc], id_extended, 1, obj);
+        rb_funcall(argv[argc], id_extend_object, 1, obj);
+        rb_funcall(argv[argc], id_extended, 1, obj);
     }
     return obj;
 }
 
+VALUE
+rb_top_main_class(const char *method)
+{
+    VALUE klass = GET_THREAD()->top_wrapper;
+
+    if (!klass) return rb_cObject;
+    rb_warning("main.%s in the wrapped load is effective only in wrapper module", method);
+    return klass;
+}
+
 /*
  *  call-seq:
  *     include(module, ...)   -> self
@@ -1775,13 +1799,7 @@ rb_obj_extend(int argc, VALUE *argv, VALUE obj)
 static VALUE
 top_include(int argc, VALUE *argv, VALUE self)
 {
-    rb_thread_t *th = GET_THREAD();
-
-    if (th->top_wrapper) {
-	rb_warning("main.include in the wrapped load is effective only in wrapper module");
-	return rb_mod_include(argc, argv, th->top_wrapper);
-    }
-    return rb_mod_include(argc, argv, rb_cObject);
+    return rb_mod_include(argc, argv, rb_top_main_class("include"));
 }
 
 /*
@@ -1795,14 +1813,16 @@ top_include(int argc, VALUE *argv, VALUE self)
 static VALUE
 top_using(VALUE self, VALUE module)
 {
-    const rb_cref_t *cref = rb_vm_cref();
+    const rb_cref_t *cref = CREF_NEXT(rb_vm_cref());;
     rb_control_frame_t *prev_cfp = previous_frame(GET_EC());
+    rb_thread_t *th = GET_THREAD();
 
-    if (CREF_NEXT(cref) || (prev_cfp && rb_vm_frame_method_entry(prev_cfp))) {
-	rb_raise(rb_eRuntimeError, "main.using is permitted only at toplevel");
+    if ((th->top_wrapper ? CREF_NEXT(cref) : cref) ||
+        (prev_cfp && rb_vm_frame_method_entry(prev_cfp))) {
+        rb_raise(rb_eRuntimeError, "main.using is permitted only at toplevel");
     }
     if (rb_block_given_p()) {
-	ignored_block(module, "main.");
+        ignored_block(module, "main.");
     }
     rb_using_module(rb_vm_cref_replace_with_duplicated_cref(), module);
     return self;
@@ -1815,17 +1835,17 @@ errinfo_place(const rb_execution_context_t *ec)
     const rb_control_frame_t *end_cfp = RUBY_VM_END_CONTROL_FRAME(ec);
 
     while (RUBY_VM_VALID_CONTROL_FRAME_P(cfp, end_cfp)) {
-	if (VM_FRAME_RUBYFRAME_P(cfp)) {
+        if (VM_FRAME_RUBYFRAME_P(cfp)) {
             if (ISEQ_BODY(cfp->iseq)->type == ISEQ_TYPE_RESCUE) {
-		return &cfp->ep[VM_ENV_INDEX_LAST_LVAR];
-	    }
+                return &cfp->ep[VM_ENV_INDEX_LAST_LVAR];
+            }
             else if (ISEQ_BODY(cfp->iseq)->type == ISEQ_TYPE_ENSURE &&
-		     !THROW_DATA_P(cfp->ep[VM_ENV_INDEX_LAST_LVAR]) &&
-		     !FIXNUM_P(cfp->ep[VM_ENV_INDEX_LAST_LVAR])) {
-		return &cfp->ep[VM_ENV_INDEX_LAST_LVAR];
-	    }
-	}
-	cfp = RUBY_VM_PREVIOUS_CONTROL_FRAME(cfp);
+                     !THROW_DATA_P(cfp->ep[VM_ENV_INDEX_LAST_LVAR]) &&
+                     !FIXNUM_P(cfp->ep[VM_ENV_INDEX_LAST_LVAR])) {
+                return &cfp->ep[VM_ENV_INDEX_LAST_LVAR];
+            }
+        }
+        cfp = RUBY_VM_PREVIOUS_CONTROL_FRAME(cfp);
     }
     return 0;
 }
@@ -1835,10 +1855,10 @@ rb_ec_get_errinfo(const rb_execution_context_t *ec)
 {
     const VALUE *ptr = errinfo_place(ec);
     if (ptr) {
-	return *ptr;
+        return *ptr;
     }
     else {
-	return ec->errinfo;
+        return ec->errinfo;
     }
 }
 
@@ -1864,7 +1884,7 @@ void
 rb_set_errinfo(VALUE err)
 {
     if (!NIL_P(err) && !rb_obj_is_kind_of(err, rb_eException)) {
-	rb_raise(rb_eTypeError, "assigning non-exception to $!");
+        rb_raise(rb_eTypeError, "assigning non-exception to $!");
     }
     GET_EC()->errinfo = err;
 }
@@ -1874,10 +1894,10 @@ errat_getter(ID id, VALUE *_)
 {
     VALUE err = get_errinfo();
     if (!NIL_P(err)) {
-	return rb_get_backtrace(err);
+        return rb_get_backtrace(err);
     }
     else {
-	return Qnil;
+        return Qnil;
     }
 }
 
@@ -1886,7 +1906,7 @@ errat_setter(VALUE val, ID id, VALUE *var)
 {
     VALUE err = get_errinfo();
     if (NIL_P(err)) {
-	rb_raise(rb_eArgError, "$! not set");
+        rb_raise(rb_eArgError, "$! not set");
     }
     set_backtrace(err, val);
 }
@@ -1907,10 +1927,10 @@ rb_f_method_name(VALUE _)
     ID fname = prev_frame_func(); /* need *method* ID */
 
     if (fname) {
-	return ID2SYM(fname);
+        return ID2SYM(fname);
     }
     else {
-	return Qnil;
+        return Qnil;
     }
 }
 
@@ -1929,10 +1949,10 @@ rb_f_callee_name(VALUE _)
     ID fname = prev_frame_callee(); /* need *callee* ID */
 
     if (fname) {
-	return ID2SYM(fname);
+        return ID2SYM(fname);
     }
     else {
-	return Qnil;
+        return Qnil;
     }
 }
 
@@ -1951,7 +1971,7 @@ f_current_dirname(VALUE _)
 {
     VALUE base = rb_current_realfilepath();
     if (NIL_P(base)) {
-	return Qnil;
+        return Qnil;
     }
     base = rb_file_dirname(base);
     return base;
@@ -2048,7 +2068,7 @@ Init_eval(void)
     rb_define_private_method(rb_cModule, "using", mod_using, 1);
     rb_define_method(rb_cModule, "refinements", mod_refinements, 0);
     rb_define_singleton_method(rb_cModule, "used_modules",
-			       rb_mod_s_used_modules, 0);
+                               rb_mod_s_used_modules, 0);
     rb_define_singleton_method(rb_cModule, "used_refinements",
                                rb_mod_s_used_refinements, 0);
     rb_undef_method(rb_cClass, "refine");
@@ -2067,9 +2087,9 @@ Init_eval(void)
     rb_define_singleton_method(rb_cModule, "constants", rb_mod_s_constants, -1);
 
     rb_define_private_method(rb_singleton_class(rb_vm_top_self()),
-			     "include", top_include, -1);
+                             "include", top_include, -1);
     rb_define_private_method(rb_singleton_class(rb_vm_top_self()),
-			     "using", top_using, 1);
+                             "using", top_using, 1);
 
     rb_define_method(rb_mKernel, "extend", rb_obj_extend, -1);
 
diff --git a/eval_error.c b/eval_error.c
index abbb708bd5..9806683000 100644
--- a/eval_error.c
+++ b/eval_error.c
@@ -10,8 +10,8 @@
 #ifdef HAVE_BUILTIN___BUILTIN_CONSTANT_P
 #define warn_print(x) RB_GNUC_EXTENSION_BLOCK(	\
     (__builtin_constant_p(x)) ? 		\
-	rb_write_error2((x), (long)strlen(x)) : \
-	rb_write_error(x)			\
+        rb_write_error2((x), (long)strlen(x)) : \
+        rb_write_error(x)			\
 )
 #else
 #define warn_print(x) rb_write_error(x)
@@ -29,7 +29,7 @@ error_pos(const VALUE str)
 {
     VALUE pos = error_pos_str();
     if (!NIL_P(pos)) {
-	write_warn_str(str, pos);
+        write_warn_str(str, pos);
     }
 }
 
@@ -40,18 +40,18 @@ error_pos_str(void)
     VALUE sourcefile = rb_source_location(&sourceline);
 
     if (!NIL_P(sourcefile)) {
-	ID caller_name;
-	if (sourceline == 0) {
-	    return rb_sprintf("%"PRIsVALUE": ", sourcefile);
-	}
-	else if ((caller_name = rb_frame_callee()) != 0) {
-	    return rb_sprintf("%"PRIsVALUE":%d:in `%"PRIsVALUE"': ",
-			      sourcefile, sourceline,
-			      rb_id2str(caller_name));
-	}
-	else {
-	    return rb_sprintf("%"PRIsVALUE":%d: ", sourcefile, sourceline);
-	}
+        ID caller_name;
+        if (sourceline == 0) {
+            return rb_sprintf("%"PRIsVALUE": ", sourcefile);
+        }
+        else if ((caller_name = rb_frame_callee()) != 0) {
+            return rb_sprintf("%"PRIsVALUE":%d:in `%"PRIsVALUE"': ",
+                              sourcefile, sourceline,
+                              rb_id2str(caller_name));
+        }
+        else {
+            return rb_sprintf("%"PRIsVALUE":%d: ", sourcefile, sourceline);
+        }
     }
     return Qnil;
 }
@@ -62,23 +62,17 @@ set_backtrace(VALUE info, VALUE bt)
     ID set_backtrace = rb_intern("set_backtrace");
 
     if (rb_backtrace_p(bt)) {
-	if (rb_method_basic_definition_p(CLASS_OF(info), set_backtrace)) {
-	    rb_exc_set_backtrace(info, bt);
-	    return;
-	}
-	else {
-	    bt = rb_backtrace_to_str_ary(bt);
-	}
+        if (rb_method_basic_definition_p(CLASS_OF(info), set_backtrace)) {
+            rb_exc_set_backtrace(info, bt);
+            return;
+        }
+        else {
+            bt = rb_backtrace_to_str_ary(bt);
+        }
     }
     rb_check_funcall(info, set_backtrace, 1, &bt);
 }
 
-static void
-error_print(rb_execution_context_t *ec)
-{
-    rb_ec_error_print(ec, ec->errinfo);
-}
-
 #define CSI_BEGIN "\033["
 #define CSI_SGR "m"
 
@@ -106,24 +100,24 @@ print_errinfo(const VALUE eclass, const VALUE errat, const VALUE emesg, const VA
     }
 
     if (eclass == rb_eRuntimeError && elen == 0) {
-	if (highlight) write_warn(str, underline);
-	write_warn(str, "unhandled exception");
-	if (highlight) write_warn(str, reset);
-	write_warn2(str, "\n", 1);
+        if (highlight) write_warn(str, underline);
+        write_warn(str, "unhandled exception");
+        if (highlight) write_warn(str, reset);
+        write_warn2(str, "\n", 1);
     }
     else {
-	VALUE epath;
-
-	epath = rb_class_name(eclass);
-	if (elen == 0) {
-	    if (highlight) write_warn(str, underline);
-	    write_warn_str(str, epath);
-	    if (highlight) write_warn(str, reset);
-	    write_warn(str, "\n");
-	}
-	else {
-	    write_warn_str(str, emesg);
-	    write_warn(str, "\n");
+        VALUE epath;
+
+        epath = rb_class_name(eclass);
+        if (elen == 0) {
+            if (highlight) write_warn(str, underline);
+            write_warn_str(str, epath);
+            if (highlight) write_warn(str, reset);
+            write_warn(str, "\n");
+        }
+        else {
+            write_warn_str(str, emesg);
+            write_warn(str, "\n");
         }
     }
 }
@@ -141,73 +135,73 @@ rb_decorate_message(const VALUE eclass, const VALUE emesg, int highlight)
         elen = RSTRING_LEN(emesg);
     }
     if (eclass == rb_eRuntimeError && elen == 0) {
-	if (highlight) write_warn(str, underline);
-	write_warn(str, "unhandled exception");
-	if (highlight) write_warn(str, reset);
+        if (highlight) write_warn(str, underline);
+        write_warn(str, "unhandled exception");
+        if (highlight) write_warn(str, reset);
     }
     else {
-	VALUE epath;
-
-	epath = rb_class_name(eclass);
-	if (elen == 0) {
-	    if (highlight) write_warn(str, underline);
-	    write_warn_str(str, epath);
-	    if (highlight) write_warn(str, reset);
-	}
-	else {
+        VALUE epath;
+
+        epath = rb_class_name(eclass);
+        if (elen == 0) {
+            if (highlight) write_warn(str, underline);
+            write_warn_str(str, epath);
+            if (highlight) write_warn(str, reset);
+        }
+        else {
             /* emesg is a String instance */
-	    const char *tail = 0;
+            const char *tail = 0;
 
             if (highlight) write_warn(str, bold);
-	    if (RSTRING_PTR(epath)[0] == '#')
-		epath = 0;
-	    if ((tail = memchr(einfo, '\n', elen)) != 0) {
+            if (RSTRING_PTR(epath)[0] == '#')
+                epath = 0;
+            if ((tail = memchr(einfo, '\n', elen)) != 0) {
                 write_warn2(str, einfo, tail - einfo);
-		tail++;		/* skip newline */
-	    }
-	    else {
+                tail++;		/* skip newline */
+            }
+            else {
                 write_warn_str(str, emesg);
-	    }
-	    if (epath) {
-		write_warn(str, " (");
-		if (highlight) write_warn(str, underline);
+            }
+            if (epath) {
+                write_warn(str, " (");
+                if (highlight) write_warn(str, underline);
                 write_warn_str(str, epath);
-		if (highlight) {
-		    write_warn(str, reset);
-		    write_warn(str, bold);
-		}
-		write_warn2(str, ")", 1);
-		if (highlight) write_warn(str, reset);
-	    }
-	    if (tail && einfo+elen > tail) {
-		if (!highlight) {
+                if (highlight) {
+                    write_warn(str, reset);
+                    write_warn(str, bold);
+                }
+                write_warn2(str, ")", 1);
+                if (highlight) write_warn(str, reset);
+            }
+            if (tail && einfo+elen > tail) {
+                if (!highlight) {
                     write_warn2(str, "\n", 1);
                     write_warn2(str, tail, einfo+elen-tail);
-		}
-		else {
-		    elen -= tail - einfo;
-		    einfo = tail;
+                }
+                else {
+                    elen -= tail - einfo;
+                    einfo = tail;
                     write_warn2(str, "\n", 1);
-		    while (elen > 0) {
-			tail = memchr(einfo, '\n', elen);
-			if (!tail || tail > einfo) {
-			    write_warn(str, bold);
+                    while (elen > 0) {
+                        tail = memchr(einfo, '\n', elen);
+                        if (!tail || tail > einfo) {
+                            write_warn(str, bold);
                             write_warn2(str, einfo, tail ? tail-einfo : elen);
-			    write_warn(str, reset);
-			    if (!tail) {
-				break;
-			    }
-			}
-			elen -= tail - einfo;
-			einfo = tail;
-			do ++tail; while (tail < einfo+elen && *tail == '\n');
+                            write_warn(str, reset);
+                            if (!tail) {
+                                break;
+                            }
+                        }
+                        elen -= tail - einfo;
+                        einfo = tail;
+                        do ++tail; while (tail < einfo+elen && *tail == '\n');
                         write_warn2(str, einfo, tail-einfo);
-			elen -= tail - einfo;
-			einfo = tail;
-		    }
-		}
-	    }
-	}
+                        elen -= tail - einfo;
+                        einfo = tail;
+                    }
+                }
+            }
+        }
     }
 
     return str;
@@ -217,13 +211,13 @@ static void
 print_backtrace(const VALUE eclass, const VALUE errat, const VALUE str, int reverse, long backtrace_limit)
 {
     if (!NIL_P(errat)) {
-	long i;
-	long len = RARRAY_LEN(errat);
-	const int threshold = 1000000000;
+        long i;
+        long len = RARRAY_LEN(errat);
+        const int threshold = 1000000000;
         int width = (len <= 1) ? INT_MIN : ((int)log10((double)(len > threshold ?
-					 ((len - 1) / threshold) :
-					 len - 1)) +
-		     (len < threshold ? 0 : 9) + 1);
+                                         ((len - 1) / threshold) :
+                                         len - 1)) +
+                     (len < threshold ? 0 : 9) + 1);
 
         long skip_start = -1, skip_len = 0;
 
@@ -244,19 +238,19 @@ print_backtrace(const VALUE eclass, const VALUE errat, const VALUE str, int reve
             skip_len = len - skip_start;
         }
 
-	for (i = 1; i < len; i++) {
-	    if (i == skip_start) {
-		write_warn_str(str, rb_sprintf("\t ... %ld levels...\n", skip_len));
-		i += skip_len;
+        for (i = 1; i < len; i++) {
+            if (i == skip_start) {
+                write_warn_str(str, rb_sprintf("\t ... %ld levels...\n", skip_len));
+                i += skip_len;
                 if (i >= len) break;
-	    }
-	    VALUE line = RARRAY_AREF(errat, reverse ? len - i : i);
-	    if (RB_TYPE_P(line, T_STRING)) {
-		VALUE bt = rb_str_new_cstr("\t");
-		if (reverse) rb_str_catf(bt, "%*ld: ", width, len - i);
-		write_warn_str(str, rb_str_catf(bt, "from %"PRIsVALUE"\n", line));
-	    }
-	}
+            }
+            VALUE line = RARRAY_AREF(errat, reverse ? len - i : i);
+            if (RB_TYPE_P(line, T_STRING)) {
+                VALUE bt = rb_str_new_cstr("\t");
+                if (reverse) rb_str_catf(bt, "%*ld: ", width, len - i);
+                write_warn_str(str, rb_str_catf(bt, "from %"PRIsVALUE"\n", line));
+            }
+        }
     }
 }
 
@@ -297,6 +291,17 @@ show_cause(VALUE errinfo, VALUE str, VALUE opt, VALUE highlight, VALUE reverse,
 }
 
 void
+rb_exc_check_circular_cause(VALUE exc)
+{
+    VALUE cause = exc, shown_causes = 0;
+    do {
+        if (shown_cause_p(cause, &shown_causes)) {
+            rb_raise(rb_eArgError, "circular causes");
+        }
+    } while (!NIL_P(cause = rb_attr_get(cause, id_cause)));
+}
+
+void
 rb_error_write(VALUE errinfo, VALUE emesg, VALUE errat, VALUE str, VALUE opt, VALUE highlight, VALUE reverse)
 {
     volatile VALUE eclass;
@@ -304,68 +309,68 @@ rb_error_write(VALUE errinfo, VALUE emesg, VALUE errat, VALUE str, VALUE opt, VA
     long backtrace_limit = rb_backtrace_length_limit;
 
     if (NIL_P(errinfo))
-	return;
+        return;
 
-    if (errat == Qundef) {
-	errat = Qnil;
+    if (UNDEF_P(errat)) {
+        errat = Qnil;
     }
     eclass = CLASS_OF(errinfo);
     if (reverse) {
-	static const char traceback[] = "Traceback "
-	    "(most recent call last):\n";
-	const int bold_part = rb_strlen_lit("Traceback");
-	char buff[sizeof(traceback)+sizeof(bold)+sizeof(reset)-2], *p = buff;
-	const char *msg = traceback;
-	long len = sizeof(traceback) - 1;
-	if (RTEST(highlight)) {
+        static const char traceback[] = "Traceback "
+            "(most recent call last):\n";
+        const int bold_part = rb_strlen_lit("Traceback");
+        char buff[sizeof(traceback)+sizeof(bold)+sizeof(reset)-2], *p = buff;
+        const char *msg = traceback;
+        long len = sizeof(traceback) - 1;
+        if (RTEST(highlight)) {
 #define APPEND(s, l) (memcpy(p, s, l), p += (l))
-	    APPEND(bold, sizeof(bold)-1);
-	    APPEND(traceback, bold_part);
-	    APPEND(reset, sizeof(reset)-1);
-	    APPEND(traceback + bold_part, sizeof(traceback)-bold_part-1);
+            APPEND(bold, sizeof(bold)-1);
+            APPEND(traceback, bold_part);
+            APPEND(reset, sizeof(reset)-1);
+            APPEND(traceback + bold_part, sizeof(traceback)-bold_part-1);
 #undef APPEND
-	    len = p - (msg = buff);
-	}
-	write_warn2(str, msg, len);
+            len = p - (msg = buff);
+        }
+        write_warn2(str, msg, len);
         show_cause(errinfo, str, opt, highlight, reverse, backtrace_limit, &shown_causes);
-	print_backtrace(eclass, errat, str, TRUE, backtrace_limit);
-	print_errinfo(eclass, errat, emesg, str, RTEST(highlight));
+        print_backtrace(eclass, errat, str, TRUE, backtrace_limit);
+        print_errinfo(eclass, errat, emesg, str, RTEST(highlight));
     }
     else {
-	print_errinfo(eclass, errat, emesg, str, RTEST(highlight));
-	print_backtrace(eclass, errat, str, FALSE, backtrace_limit);
+        print_errinfo(eclass, errat, emesg, str, RTEST(highlight));
+        print_backtrace(eclass, errat, str, FALSE, backtrace_limit);
         show_cause(errinfo, str, opt, highlight, reverse, backtrace_limit, &shown_causes);
     }
 }
 
-void
-rb_ec_error_print(rb_execution_context_t * volatile ec, volatile VALUE errinfo)
+static void
+rb_ec_error_print_detailed(rb_execution_context_t *const ec, const VALUE errinfo, const VALUE str, VALUE emesg0)
 {
     volatile uint8_t raised_flag = ec->raised_flag;
     volatile VALUE errat = Qundef;
-    volatile VALUE emesg = Qundef;
     volatile bool written = false;
+    volatile VALUE emesg = emesg0;
 
     VALUE opt = rb_hash_new();
     VALUE highlight = rb_stderr_tty_p() ? Qtrue : Qfalse;
     rb_hash_aset(opt, ID2SYM(rb_intern_const("highlight")), highlight);
 
     if (NIL_P(errinfo))
-	return;
+        return;
     rb_ec_raised_clear(ec);
 
     EC_PUSH_TAG(ec);
     if (EC_EXEC_TAG() == TAG_NONE) {
-	errat = rb_get_backtrace(errinfo);
+        errat = rb_get_backtrace(errinfo);
     }
-    if (emesg == Qundef) {
-	emesg = Qnil;
-	emesg = rb_get_detailed_message(errinfo, opt);
+    if (UNDEF_P(emesg)) {
+        emesg = Qnil;
+        emesg = rb_get_detailed_message(errinfo, opt);
     }
 
     if (!written) {
         written = true;
-        rb_error_write(errinfo, emesg, errat, Qnil, opt, highlight, Qfalse);
+        rb_error_write(errinfo, emesg, errat, str, opt, highlight, Qfalse);
     }
 
     EC_POP_TAG();
@@ -373,11 +378,17 @@ rb_ec_error_print(rb_execution_context_t * volatile ec, volatile VALUE errinfo)
     rb_ec_raised_set(ec, raised_flag);
 }
 
+void
+rb_ec_error_print(rb_execution_context_t *volatile ec, volatile VALUE errinfo)
+{
+    rb_ec_error_print_detailed(ec, errinfo, Qnil, Qundef);
+}
+
 #define undef_mesg_for(v, k) rb_fstring_lit("undefined"v" method `%1$s' for "k" `%2$s'")
 #define undef_mesg(v) ( \
-	is_mod ? \
-	undef_mesg_for(v, "module") : \
-	undef_mesg_for(v, "class"))
+        is_mod ? \
+        undef_mesg_for(v, "module") : \
+        undef_mesg_for(v, "class"))
 
 void
 rb_print_undef(VALUE klass, ID id, rb_method_visibility_t visi)
@@ -403,9 +414,9 @@ rb_print_undef_str(VALUE klass, VALUE name)
 
 #define inaccessible_mesg_for(v, k) rb_fstring_lit("method `%1$s' for "k" `%2$s' is "v)
 #define inaccessible_mesg(v) ( \
-	is_mod ? \
-	inaccessible_mesg_for(v, "module") : \
-	inaccessible_mesg_for(v, "class"))
+        is_mod ? \
+        inaccessible_mesg_for(v, "module") : \
+        inaccessible_mesg_for(v, "class"))
 
 void
 rb_print_inaccessible(VALUE klass, ID id, rb_method_visibility_t visi)
@@ -429,70 +440,109 @@ sysexit_status(VALUE err)
     return NUM2INT(st);
 }
 
+enum {
+    EXITING_WITH_MESSAGE = 1,
+    EXITING_WITH_STATUS = 2,
+    EXITING_WITH_SIGNAL = 4
+};
+static int
+exiting_split(VALUE errinfo, volatile int *exitcode, volatile int *sigstatus)
+{
+    int ex = EXIT_SUCCESS;
+    VALUE signo;
+    int sig = 0;
+    int result = 0;
+
+    if (NIL_P(errinfo)) return 0;
+
+    if (THROW_DATA_P(errinfo)) {
+        int throw_state = ((const struct vm_throw_data *)errinfo)->throw_state;
+        ex = throw_state & VM_THROW_STATE_MASK;
+        result |= EXITING_WITH_STATUS;
+    }
+    else if (rb_obj_is_kind_of(errinfo, rb_eSystemExit)) {
+        ex = sysexit_status(errinfo);
+        result |= EXITING_WITH_STATUS;
+    }
+    else if (rb_obj_is_kind_of(errinfo, rb_eSignal)) {
+        signo = rb_ivar_get(errinfo, id_signo);
+        sig = FIX2INT(signo);
+        result |= EXITING_WITH_SIGNAL;
+        /* no message when exiting by signal */
+        if (signo == INT2FIX(SIGSEGV) || !rb_obj_is_instance_of(errinfo, rb_eSignal))
+            /* except for SEGV and subclasses */
+            result |= EXITING_WITH_MESSAGE;
+    }
+    else if (rb_obj_is_kind_of(errinfo, rb_eSystemCallError) &&
+        FIXNUM_P(signo = rb_attr_get(errinfo, id_signo))) {
+        sig = FIX2INT(signo);
+        result |= EXITING_WITH_SIGNAL;
+        /* no message when exiting by error to be mapped to signal */
+    }
+    else {
+        ex = EXIT_FAILURE;
+        result |= EXITING_WITH_STATUS | EXITING_WITH_MESSAGE;
+    }
+
+    if (exitcode && (result & EXITING_WITH_STATUS))
+        *exitcode = ex;
+    if (sigstatus && (result & EXITING_WITH_SIGNAL))
+        *sigstatus = sig;
+
+    return result;
+}
+
 #define unknown_longjmp_status(status) \
     rb_bug("Unknown longjmp status %d", status)
 
 static int
-error_handle(rb_execution_context_t *ec, int ex)
+error_handle(rb_execution_context_t *ec, VALUE errinfo, enum ruby_tag_type ex)
 {
     int status = EXIT_FAILURE;
 
     if (rb_ec_set_raised(ec))
-	return EXIT_FAILURE;
+        return EXIT_FAILURE;
     switch (ex & TAG_MASK) {
       case 0:
-	status = EXIT_SUCCESS;
-	break;
+        status = EXIT_SUCCESS;
+        break;
 
       case TAG_RETURN:
-	error_pos(Qnil);
-	warn_print("unexpected return\n");
-	break;
+        error_pos(Qnil);
+        warn_print("unexpected return\n");
+        break;
       case TAG_NEXT:
-	error_pos(Qnil);
-	warn_print("unexpected next\n");
-	break;
+        error_pos(Qnil);
+        warn_print("unexpected next\n");
+        break;
       case TAG_BREAK:
-	error_pos(Qnil);
-	warn_print("unexpected break\n");
-	break;
+        error_pos(Qnil);
+        warn_print("unexpected break\n");
+        break;
       case TAG_REDO:
-	error_pos(Qnil);
-	warn_print("unexpected redo\n");
-	break;
+        error_pos(Qnil);
+        warn_print("unexpected redo\n");
+        break;
       case TAG_RETRY:
-	error_pos(Qnil);
-	warn_print("retry outside of rescue clause\n");
-	break;
+        error_pos(Qnil);
+        warn_print("retry outside of rescue clause\n");
+        break;
       case TAG_THROW:
-	/* TODO: fix me */
-	error_pos(Qnil);
-	warn_print("unexpected throw\n");
-	break;
-      case TAG_RAISE: {
-	VALUE errinfo = ec->errinfo;
-	if (rb_obj_is_kind_of(errinfo, rb_eSystemExit)) {
-	    status = sysexit_status(errinfo);
-	}
-	else if (rb_obj_is_instance_of(errinfo, rb_eSignal) &&
-		 rb_ivar_get(errinfo, id_signo) != INT2FIX(SIGSEGV)) {
-	    /* no message when exiting by signal */
-	}
-        else if (rb_obj_is_kind_of(errinfo, rb_eSystemCallError) &&
-                 FIXNUM_P(rb_attr_get(errinfo, id_signo))) {
-	    /* no message when exiting by error to be mapped to signal */
+        /* TODO: fix me */
+        error_pos(Qnil);
+        warn_print("unexpected throw\n");
+        break;
+      case TAG_RAISE:
+        if (!(exiting_split(errinfo, &status, NULL) & EXITING_WITH_MESSAGE)) {
+            break;
         }
-	else {
-	    rb_ec_error_print(ec, errinfo);
-	}
-	break;
-      }
+        /* fallthrough */
       case TAG_FATAL:
-	error_print(ec);
-	break;
+        rb_ec_error_print(ec, errinfo);
+        break;
       default:
-	unknown_longjmp_status(ex);
-	break;
+        unknown_longjmp_status(ex);
+        break;
     }
     rb_ec_reset_raised(ec);
     return status;
diff --git a/eval_intern.h b/eval_intern.h
index 0efbcb0441..6cbaa51361 100644
--- a/eval_intern.h
+++ b/eval_intern.h
@@ -329,9 +329,9 @@ static inline void
 translit_char(char *p, int from, int to)
 {
     while (*p) {
-	if ((unsigned char)*p == from)
-	    *p = to;
-	p = CharNext(p);
+        if ((unsigned char)*p == from)
+            *p = to;
+        p = CharNext(p);
     }
 }
 #endif
diff --git a/eval_jump.c b/eval_jump.c
index 2ea73b0da3..e8e74f4e70 100644
--- a/eval_jump.c
+++ b/eval_jump.c
@@ -40,7 +40,7 @@ rb_f_at_exit(VALUE _)
     VALUE proc;
 
     if (!rb_block_given_p()) {
-	rb_raise(rb_eArgError, "called without a block");
+        rb_raise(rb_eArgError, "called without a block");
     }
     proc = rb_block_proc();
     rb_set_end_proc(rb_call_end_proc, proc);
@@ -63,10 +63,10 @@ rb_set_end_proc(void (*func)(VALUE), VALUE data)
     rb_thread_t *th = GET_THREAD();
 
     if (th->top_wrapper) {
-	list = &ephemeral_end_procs;
+        list = &ephemeral_end_procs;
     }
     else {
-	list = &end_procs;
+        list = &end_procs;
     }
     link->next = *list;
     link->func = func;
@@ -81,13 +81,13 @@ rb_mark_end_proc(void)
 
     link = end_procs;
     while (link) {
-	rb_gc_mark(link->data);
-	link = link->next;
+        rb_gc_mark(link->data);
+        link = link->next;
     }
     link = ephemeral_end_procs;
     while (link) {
-	rb_gc_mark(link->data);
-	link = link->next;
+        rb_gc_mark(link->data);
+        link = link->next;
     }
 }
 
@@ -99,11 +99,11 @@ exec_end_procs_chain(struct end_proc_data *volatile *procs, VALUE *errp)
     VALUE errinfo = *errp;
 
     while ((link = *procs) != 0) {
-	*procs = link->next;
-	endproc = *link;
-	xfree(link);
-	(*endproc.func) (endproc.data);
-	*errp = errinfo;
+        *procs = link->next;
+        endproc = *link;
+        xfree(link);
+        (*endproc.func) (endproc.data);
+        *errp = errinfo;
     }
 }
 
@@ -116,15 +116,15 @@ rb_ec_exec_end_proc(rb_execution_context_t * ec)
     EC_PUSH_TAG(ec);
     if ((state = EC_EXEC_TAG()) == TAG_NONE) {
       again:
-	exec_end_procs_chain(&ephemeral_end_procs, &ec->errinfo);
-	exec_end_procs_chain(&end_procs, &ec->errinfo);
+        exec_end_procs_chain(&ephemeral_end_procs, &ec->errinfo);
+        exec_end_procs_chain(&end_procs, &ec->errinfo);
     }
     else {
-	EC_TMPPOP_TAG();
-        error_handle(ec, state);
-	if (!NIL_P(ec->errinfo)) errinfo = ec->errinfo;
-	EC_REPUSH_TAG();
-	goto again;
+        EC_TMPPOP_TAG();
+        error_handle(ec, ec->errinfo, state);
+        if (!NIL_P(ec->errinfo)) errinfo = ec->errinfo;
+        EC_REPUSH_TAG();
+        goto again;
     }
     EC_POP_TAG();
 
diff --git a/ext/-test-/abi/extconf.rb b/ext/-test-/abi/extconf.rb
index d786b15db9..3b090b7553 100644
--- a/ext/-test-/abi/extconf.rb
+++ b/ext/-test-/abi/extconf.rb
@@ -1,3 +1,4 @@
 # frozen_string_literal: false
+return unless RUBY_PATCHLEVEL < 0
 require_relative "../auto_ext.rb"
 auto_ext(inc: true)
diff --git a/ext/-test-/arith_seq/beg_len_step/beg_len_step.c b/ext/-test-/arith_seq/beg_len_step/beg_len_step.c
new file mode 100644
index 0000000000..40c8cbee82
--- /dev/null
+++ b/ext/-test-/arith_seq/beg_len_step/beg_len_step.c
@@ -0,0 +1,19 @@
+#include "ruby/ruby.h"
+
+static VALUE
+arith_seq_s_beg_len_step(VALUE mod, VALUE obj, VALUE len, VALUE err)
+{
+  VALUE r;
+  long beg, len2, step;
+
+  r = rb_arithmetic_sequence_beg_len_step(obj, &beg, &len2, &step, NUM2LONG(len), NUM2INT(err));
+
+  return rb_ary_new_from_args(4, r, LONG2NUM(beg), LONG2NUM(len2), LONG2NUM(step));
+}
+
+void
+Init_beg_len_step(void)
+{
+    VALUE cArithSeq = rb_path2class("Enumerator::ArithmeticSequence");
+    rb_define_singleton_method(cArithSeq, "__beg_len_step__", arith_seq_s_beg_len_step, 3);
+}
diff --git a/ext/-test-/arith_seq/beg_len_step/depend b/ext/-test-/arith_seq/beg_len_step/depend
new file mode 100644
index 0000000000..36a2c4c71b
--- /dev/null
+++ b/ext/-test-/arith_seq/beg_len_step/depend
@@ -0,0 +1,161 @@
+# AUTOGENERATED DEPENDENCIES START
+beg_len_step.o: $(RUBY_EXTCONF_H)
+beg_len_step.o: $(arch_hdrdir)/ruby/config.h
+beg_len_step.o: $(hdrdir)/ruby/assert.h
+beg_len_step.o: $(hdrdir)/ruby/backward.h
+beg_len_step.o: $(hdrdir)/ruby/backward/2/assume.h
+beg_len_step.o: $(hdrdir)/ruby/backward/2/attributes.h
+beg_len_step.o: $(hdrdir)/ruby/backward/2/bool.h
+beg_len_step.o: $(hdrdir)/ruby/backward/2/inttypes.h
+beg_len_step.o: $(hdrdir)/ruby/backward/2/limits.h
+beg_len_step.o: $(hdrdir)/ruby/backward/2/long_long.h
+beg_len_step.o: $(hdrdir)/ruby/backward/2/stdalign.h
+beg_len_step.o: $(hdrdir)/ruby/backward/2/stdarg.h
+beg_len_step.o: $(hdrdir)/ruby/defines.h
+beg_len_step.o: $(hdrdir)/ruby/intern.h
+beg_len_step.o: $(hdrdir)/ruby/internal/abi.h
+beg_len_step.o: $(hdrdir)/ruby/internal/anyargs.h
+beg_len_step.o: $(hdrdir)/ruby/internal/arithmetic.h
+beg_len_step.o: $(hdrdir)/ruby/internal/arithmetic/char.h
+beg_len_step.o: $(hdrdir)/ruby/internal/arithmetic/double.h
+beg_len_step.o: $(hdrdir)/ruby/internal/arithmetic/fixnum.h
+beg_len_step.o: $(hdrdir)/ruby/internal/arithmetic/gid_t.h
+beg_len_step.o: $(hdrdir)/ruby/internal/arithmetic/int.h
+beg_len_step.o: $(hdrdir)/ruby/internal/arithmetic/intptr_t.h
+beg_len_step.o: $(hdrdir)/ruby/internal/arithmetic/long.h
+beg_len_step.o: $(hdrdir)/ruby/internal/arithmetic/long_long.h
+beg_len_step.o: $(hdrdir)/ruby/internal/arithmetic/mode_t.h
+beg_len_step.o: $(hdrdir)/ruby/internal/arithmetic/off_t.h
+beg_len_step.o: $(hdrdir)/ruby/internal/arithmetic/pid_t.h
+beg_len_step.o: $(hdrdir)/ruby/internal/arithmetic/short.h
+beg_len_step.o: $(hdrdir)/ruby/internal/arithmetic/size_t.h
+beg_len_step.o: $(hdrdir)/ruby/internal/arithmetic/st_data_t.h
+beg_len_step.o: $(hdrdir)/ruby/internal/arithmetic/uid_t.h
+beg_len_step.o: $(hdrdir)/ruby/internal/assume.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/alloc_size.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/artificial.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/cold.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/const.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/constexpr.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/deprecated.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/diagnose_if.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/enum_extensibility.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/error.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/flag_enum.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/forceinline.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/format.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/maybe_unused.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/noalias.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/nodiscard.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/noexcept.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/noinline.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/nonnull.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/noreturn.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/pure.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/restrict.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/returns_nonnull.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/warning.h
+beg_len_step.o: $(hdrdir)/ruby/internal/attr/weakref.h
+beg_len_step.o: $(hdrdir)/ruby/internal/cast.h
+beg_len_step.o: $(hdrdir)/ruby/internal/compiler_is.h
+beg_len_step.o: $(hdrdir)/ruby/internal/compiler_is/apple.h
+beg_len_step.o: $(hdrdir)/ruby/internal/compiler_is/clang.h
+beg_len_step.o: $(hdrdir)/ruby/internal/compiler_is/gcc.h
+beg_len_step.o: $(hdrdir)/ruby/internal/compiler_is/intel.h
+beg_len_step.o: $(hdrdir)/ruby/internal/compiler_is/msvc.h
+beg_len_step.o: $(hdrdir)/ruby/internal/compiler_is/sunpro.h
+beg_len_step.o: $(hdrdir)/ruby/internal/compiler_since.h
+beg_len_step.o: $(hdrdir)/ruby/internal/config.h
+beg_len_step.o: $(hdrdir)/ruby/internal/constant_p.h
+beg_len_step.o: $(hdrdir)/ruby/internal/core.h
+beg_len_step.o: $(hdrdir)/ruby/internal/core/rarray.h
+beg_len_step.o: $(hdrdir)/ruby/internal/core/rbasic.h
+beg_len_step.o: $(hdrdir)/ruby/internal/core/rbignum.h
+beg_len_step.o: $(hdrdir)/ruby/internal/core/rclass.h
+beg_len_step.o: $(hdrdir)/ruby/internal/core/rdata.h
+beg_len_step.o: $(hdrdir)/ruby/internal/core/rfile.h
+beg_len_step.o: $(hdrdir)/ruby/internal/core/rhash.h
+beg_len_step.o: $(hdrdir)/ruby/internal/core/robject.h
+beg_len_step.o: $(hdrdir)/ruby/internal/core/rregexp.h
+beg_len_step.o: $(hdrdir)/ruby/internal/core/rstring.h
+beg_len_step.o: $(hdrdir)/ruby/internal/core/rstruct.h
+beg_len_step.o: $(hdrdir)/ruby/internal/core/rtypeddata.h
+beg_len_step.o: $(hdrdir)/ruby/internal/ctype.h
+beg_len_step.o: $(hdrdir)/ruby/internal/dllexport.h
+beg_len_step.o: $(hdrdir)/ruby/internal/dosish.h
+beg_len_step.o: $(hdrdir)/ruby/internal/error.h
+beg_len_step.o: $(hdrdir)/ruby/internal/eval.h
+beg_len_step.o: $(hdrdir)/ruby/internal/event.h
+beg_len_step.o: $(hdrdir)/ruby/internal/fl_type.h
+beg_len_step.o: $(hdrdir)/ruby/internal/gc.h
+beg_len_step.o: $(hdrdir)/ruby/internal/glob.h
+beg_len_step.o: $(hdrdir)/ruby/internal/globals.h
+beg_len_step.o: $(hdrdir)/ruby/internal/has/attribute.h
+beg_len_step.o: $(hdrdir)/ruby/internal/has/builtin.h
+beg_len_step.o: $(hdrdir)/ruby/internal/has/c_attribute.h
+beg_len_step.o: $(hdrdir)/ruby/internal/has/cpp_attribute.h
+beg_len_step.o: $(hdrdir)/ruby/internal/has/declspec_attribute.h
+beg_len_step.o: $(hdrdir)/ruby/internal/has/extension.h
+beg_len_step.o: $(hdrdir)/ruby/internal/has/feature.h
+beg_len_step.o: $(hdrdir)/ruby/internal/has/warning.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/array.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/bignum.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/class.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/compar.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/complex.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/cont.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/dir.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/enum.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/enumerator.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/error.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/eval.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/file.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/gc.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/hash.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/io.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/load.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/marshal.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/numeric.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/object.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/parse.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/proc.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/process.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/random.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/range.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/rational.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/re.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/ruby.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/select.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/select/largesize.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/signal.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/sprintf.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/string.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/struct.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/thread.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/time.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/variable.h
+beg_len_step.o: $(hdrdir)/ruby/internal/intern/vm.h
+beg_len_step.o: $(hdrdir)/ruby/internal/interpreter.h
+beg_len_step.o: $(hdrdir)/ruby/internal/iterator.h
+beg_len_step.o: $(hdrdir)/ruby/internal/memory.h
+beg_len_step.o: $(hdrdir)/ruby/internal/method.h
+beg_len_step.o: $(hdrdir)/ruby/internal/module.h
+beg_len_step.o: $(hdrdir)/ruby/internal/newobj.h
+beg_len_step.o: $(hdrdir)/ruby/internal/rgengc.h
+beg_len_step.o: $(hdrdir)/ruby/internal/scan_args.h
+beg_len_step.o: $(hdrdir)/ruby/internal/special_consts.h
+beg_len_step.o: $(hdrdir)/ruby/internal/static_assert.h
+beg_len_step.o: $(hdrdir)/ruby/internal/stdalign.h
+beg_len_step.o: $(hdrdir)/ruby/internal/stdbool.h
+beg_len_step.o: $(hdrdir)/ruby/internal/symbol.h
+beg_len_step.o: $(hdrdir)/ruby/internal/value.h
+beg_len_step.o: $(hdrdir)/ruby/internal/value_type.h
+beg_len_step.o: $(hdrdir)/ruby/internal/variable.h
+beg_len_step.o: $(hdrdir)/ruby/internal/warning_push.h
+beg_len_step.o: $(hdrdir)/ruby/internal/xmalloc.h
+beg_len_step.o: $(hdrdir)/ruby/missing.h
+beg_len_step.o: $(hdrdir)/ruby/ruby.h
+beg_len_step.o: $(hdrdir)/ruby/st.h
+beg_len_step.o: $(hdrdir)/ruby/subst.h
+beg_len_step.o: beg_len_step.c
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/-test-/arith_seq/beg_len_step/extconf.rb b/ext/-test-/arith_seq/beg_len_step/extconf.rb
new file mode 100644
index 0000000000..e72b3ad01f
--- /dev/null
+++ b/ext/-test-/arith_seq/beg_len_step/extconf.rb
@@ -0,0 +1,2 @@
+# frozen_string_literal: false
+create_makefile("-test-/arith_seq/beg_len_step")
diff --git a/ext/-test-/debug/inspector.c b/ext/-test-/debug/inspector.c
index f0c58e59f9..25f9d894d3 100644
--- a/ext/-test-/debug/inspector.c
+++ b/ext/-test-/debug/inspector.c
@@ -8,13 +8,13 @@ callback(const rb_debug_inspector_t *dbg_context, void *data)
     long i, len = RARRAY_LEN(locs);
     VALUE binds = rb_ary_new();
     for (i = 0; i < len; ++i) {
-	VALUE entry = rb_ary_new();
-	rb_ary_push(binds, entry);
-	rb_ary_push(entry, rb_debug_inspector_frame_self_get(dbg_context, i));
-	rb_ary_push(entry, rb_debug_inspector_frame_binding_get(dbg_context, i));
-	rb_ary_push(entry, rb_debug_inspector_frame_class_get(dbg_context, i));
-	rb_ary_push(entry, rb_debug_inspector_frame_iseq_get(dbg_context, i));
-	rb_ary_push(entry, rb_ary_entry(locs, i));
+        VALUE entry = rb_ary_new();
+        rb_ary_push(binds, entry);
+        rb_ary_push(entry, rb_debug_inspector_frame_self_get(dbg_context, i));
+        rb_ary_push(entry, rb_debug_inspector_frame_binding_get(dbg_context, i));
+        rb_ary_push(entry, rb_debug_inspector_frame_class_get(dbg_context, i));
+        rb_ary_push(entry, rb_debug_inspector_frame_iseq_get(dbg_context, i));
+        rb_ary_push(entry, rb_ary_entry(locs, i));
     }
     return binds;
 }
diff --git a/ext/-test-/debug/profile_frames.c b/ext/-test-/debug/profile_frames.c
index 1656ff7d4b..d2bba7d183 100644
--- a/ext/-test-/debug/profile_frames.c
+++ b/ext/-test-/debug/profile_frames.c
@@ -18,19 +18,20 @@ profile_frames(VALUE self, VALUE start_v, VALUE num_v)
     collected_size = rb_profile_frames(start, buff_size, buff, lines);
 
     for (i=0; i<collected_size; i++) {
-	VALUE ary = rb_ary_new();
-	rb_ary_push(ary, rb_profile_frame_path(buff[i]));
-	rb_ary_push(ary, rb_profile_frame_absolute_path(buff[i]));
-	rb_ary_push(ary, rb_profile_frame_label(buff[i]));
-	rb_ary_push(ary, rb_profile_frame_base_label(buff[i]));
-	rb_ary_push(ary, rb_profile_frame_full_label(buff[i]));
-	rb_ary_push(ary, rb_profile_frame_first_lineno(buff[i]));
-	rb_ary_push(ary, rb_profile_frame_classpath(buff[i]));
-	rb_ary_push(ary, rb_profile_frame_singleton_method_p(buff[i]));
-	rb_ary_push(ary, rb_profile_frame_method_name(buff[i]));
-	rb_ary_push(ary, rb_profile_frame_qualified_method_name(buff[i]));
-
-	rb_ary_push(result, ary);
+        VALUE ary = rb_ary_new();
+        rb_ary_push(ary, rb_profile_frame_path(buff[i]));
+        rb_ary_push(ary, rb_profile_frame_absolute_path(buff[i]));
+        rb_ary_push(ary, rb_profile_frame_label(buff[i]));
+        rb_ary_push(ary, rb_profile_frame_base_label(buff[i]));
+        rb_ary_push(ary, rb_profile_frame_full_label(buff[i]));
+        rb_ary_push(ary, rb_profile_frame_first_lineno(buff[i]));
+        rb_ary_push(ary, rb_profile_frame_classpath(buff[i]));
+        rb_ary_push(ary, rb_profile_frame_singleton_method_p(buff[i]));
+        rb_ary_push(ary, rb_profile_frame_method_name(buff[i]));
+        rb_ary_push(ary, rb_profile_frame_qualified_method_name(buff[i]));
+        rb_ary_push(ary, INT2NUM(lines[i]));
+
+        rb_ary_push(result, ary);
     }
 
     return result;
diff --git a/ext/-test-/econv/append.c b/ext/-test-/econv/append.c
new file mode 100644
index 0000000000..724cd136c0
--- /dev/null
+++ b/ext/-test-/econv/append.c
@@ -0,0 +1,15 @@
+#include "ruby/ruby.h"
+#include "ruby/encoding.h"
+
+static VALUE
+econv_append(VALUE self, VALUE src, VALUE dst)
+{
+    rb_econv_t *ec = DATA_PTR(self);
+    return rb_econv_str_append(ec, src, dst, 0);
+}
+
+void
+Init_econv_append(VALUE klass)
+{
+    rb_define_method(klass, "append", econv_append, 2);
+}
diff --git a/ext/-test-/econv/extconf.rb b/ext/-test-/econv/extconf.rb
new file mode 100644
index 0000000000..d786b15db9
--- /dev/null
+++ b/ext/-test-/econv/extconf.rb
@@ -0,0 +1,3 @@
+# frozen_string_literal: false
+require_relative "../auto_ext.rb"
+auto_ext(inc: true)
diff --git a/ext/-test-/econv/init.c b/ext/-test-/econv/init.c
new file mode 100644
index 0000000000..9772ebe71c
--- /dev/null
+++ b/ext/-test-/econv/init.c
@@ -0,0 +1,11 @@
+#include "ruby.h"
+
+#define init(n) {void Init_econv_##n(VALUE klass); Init_econv_##n(klass);}
+
+void
+Init_econv(void)
+{
+    VALUE mBug = rb_define_module("Bug");
+    VALUE klass = rb_define_class_under(mBug, "EConv", rb_path2class("Encoding::Converter"));
+    TEST_INIT_FUNCS(init);
+}
diff --git a/ext/-test-/enumerator_kw/enumerator_kw.c b/ext/-test-/enumerator_kw/enumerator_kw.c
index 947d2b37e6..9104c51869 100644
--- a/ext/-test-/enumerator_kw/enumerator_kw.c
+++ b/ext/-test-/enumerator_kw/enumerator_kw.c
@@ -14,7 +14,8 @@ enumerator_kw(int argc, VALUE *argv, VALUE self)
 }
 
 void
-Init_enumerator_kw(void) {
+Init_enumerator_kw(void)
+{
     VALUE module = rb_define_module("Bug");
     module = rb_define_module_under(module, "EnumeratorKw");
     rb_define_method(module, "m", enumerator_kw, -1);
diff --git a/ext/-test-/eval/eval.c b/ext/-test-/eval/eval.c
new file mode 100644
index 0000000000..983468fc34
--- /dev/null
+++ b/ext/-test-/eval/eval.c
@@ -0,0 +1,13 @@
+#include "ruby/ruby.h"
+
+static VALUE
+eval_string(VALUE self, VALUE str)
+{
+    return rb_eval_string(StringValueCStr(str));
+}
+
+void
+Init_eval(void)
+{
+    rb_define_global_function("rb_eval_string", eval_string, 1);
+}
diff --git a/ext/-test-/eval/extconf.rb b/ext/-test-/eval/extconf.rb
new file mode 100644
index 0000000000..cdbf6a8597
--- /dev/null
+++ b/ext/-test-/eval/extconf.rb
@@ -0,0 +1,2 @@
+require 'mkmf'
+create_makefile('-test-/eval')
diff --git a/ext/-test-/file/fs.c b/ext/-test-/file/fs.c
index 1a6c3d06dc..eb17e9768e 100644
--- a/ext/-test-/file/fs.c
+++ b/ext/-test-/file/fs.c
@@ -54,24 +54,24 @@ get_fsname(VALUE self, VALUE str)
     FilePathValue(str);
     str = rb_str_encode_ospath(str);
     if (STATFS(StringValueCStr(str), &st) == -1) {
-	rb_sys_fail_str(str);
+        rb_sys_fail_str(str);
     }
 # ifdef HAVE_STRUCT_STATFS_T_F_FSTYPENAME
     if (st.f_fstypename[0])
-	return CSTR(st.f_fstypename);
+        return CSTR(st.f_fstypename);
 # endif
 # ifdef HAVE_STRUCT_STATFS_T_F_TYPE
     switch (st.f_type) {
       case 0x9123683E: /* BTRFS_SUPER_MAGIC */
-	return CSTR("btrfs");
+        return CSTR("btrfs");
       case 0x7461636f: /* OCFS2_SUPER_MAGIC */
-	return CSTR("ocfs");
+        return CSTR("ocfs");
       case 0xEF53: /* EXT2_SUPER_MAGIC EXT3_SUPER_MAGIC EXT4_SUPER_MAGIC */
-	return CSTR("ext4");
+        return CSTR("ext4");
       case 0x58465342: /* XFS_SUPER_MAGIC */
-	return CSTR("xfs");
+        return CSTR("xfs");
       case 0x01021994: /* TMPFS_MAGIC */
-	return CSTR("tmpfs");
+        return CSTR("tmpfs");
     }
 # endif
 #endif
diff --git a/ext/-test-/funcall/funcall.c b/ext/-test-/funcall/funcall.c
index 43521bf2e9..a68d6de255 100644
--- a/ext/-test-/funcall/funcall.c
+++ b/ext/-test-/funcall/funcall.c
@@ -47,17 +47,17 @@ Init_funcall(void)
     VALUE cRelay = rb_define_module_under(cTestFuncall, "Relay");
 
     rb_define_singleton_method(cRelay,
-			       "with_funcall2",
-			       with_funcall2,
-			       -1);
+                               "with_funcall2",
+                               with_funcall2,
+                               -1);
     rb_define_singleton_method(cRelay,
                                "with_funcall_passing_block_kw",
                                with_funcall_passing_block_kw,
                                -1);
     rb_define_singleton_method(cRelay,
-			       "with_funcall_passing_block",
-			       with_funcall_passing_block,
-			       -1);
+                               "with_funcall_passing_block",
+                               with_funcall_passing_block,
+                               -1);
     rb_define_singleton_method(cRelay,
                                "with_funcallv_public_kw",
                                with_funcallv_public_kw,
diff --git a/ext/-test-/gvl/call_without_gvl/call_without_gvl.c b/ext/-test-/gvl/call_without_gvl/call_without_gvl.c
index 233635421b..97946e925d 100644
--- a/ext/-test-/gvl/call_without_gvl/call_without_gvl.c
+++ b/ext/-test-/gvl/call_without_gvl/call_without_gvl.c
@@ -17,7 +17,7 @@ thread_runnable_sleep(VALUE thread, VALUE timeout)
     struct timeval timeval;
 
     if (NIL_P(timeout)) {
-	rb_raise(rb_eArgError, "timeout must be non nil");
+        rb_raise(rb_eArgError, "timeout must be non nil");
     }
 
     timeval = rb_time_interval(timeout);
diff --git a/ext/-test-/marshal/internal_ivar/internal_ivar.c b/ext/-test-/marshal/internal_ivar/internal_ivar.c
index de0cf711aa..b2188f737a 100644
--- a/ext/-test-/marshal/internal_ivar/internal_ivar.c
+++ b/ext/-test-/marshal/internal_ivar/internal_ivar.c
@@ -36,10 +36,7 @@ Init_internal_ivar(void)
     VALUE newclass = rb_define_class_under(mMarshal, "InternalIVar", rb_cObject);
 
     id_normal_ivar = rb_intern_const("normal");
-#if 0
-    /* leave id_internal_ivar being 0 */
-    id_internal_ivar = rb_make_internal_id();
-#endif
+    id_internal_ivar = rb_intern_const("K");
     id_encoding_short = rb_intern_const("E");
     rb_define_method(newclass, "initialize", init, 3);
     rb_define_method(newclass, "normal", get_normal, 0);
diff --git a/ext/-test-/memory_status/memory_status.c b/ext/-test-/memory_status/memory_status.c
index afacbee785..f124c97ca1 100644
--- a/ext/-test-/memory_status/memory_status.c
+++ b/ext/-test-/memory_status/memory_status.c
@@ -34,7 +34,7 @@ read_status(VALUE self)
     taskinfo.virtual_size = 0;
     taskinfo.resident_size = 0;
     error = task_info(mach_task_self(), flavor,
-		      (task_info_t)&taskinfo, &out_count);
+                      (task_info_t)&taskinfo, &out_count);
     if (error != KERN_SUCCESS) return Qnil;
 #ifndef ULL2NUM
 /* "long long" does not exist here, use size_t instead.  */
@@ -50,7 +50,7 @@ read_status(VALUE self)
     PROCESS_MEMORY_COUNTERS c;
     c.cb = sizeof(c);
     if (!GetProcessMemoryInfo(GetCurrentProcess(), &c, c.cb))
-	return Qnil;
+        return Qnil;
     size = SIZET2NUM(c.PagefileUsage);
     rss = SIZET2NUM(c.WorkingSetSize);
     peak = SIZET2NUM(c.PeakWorkingSetSize);
@@ -68,13 +68,13 @@ Init_memory_status(void)
 {
     VALUE mMemory = rb_define_module("Memory");
     cMemoryStatus =
-	rb_struct_define_under(mMemory, "Status", "size",
+        rb_struct_define_under(mMemory, "Status", "size",
 #ifdef HAVE_RSS
-			       "rss",
+                               "rss",
 #endif
 #ifdef HAVE_PEAK
-			       "peak",
+                               "peak",
 #endif
-			       (char *)NULL);
+                               (char *)NULL);
     rb_define_method(cMemoryStatus, "_update", read_status, 0);
 }
diff --git a/ext/-test-/num2int/num2int.c b/ext/-test-/num2int/num2int.c
index 3aec3ccf3b..63a441fda6 100644
--- a/ext/-test-/num2int/num2int.c
+++ b/ext/-test-/num2int/num2int.c
@@ -4,7 +4,7 @@ static VALUE
 test_num2short(VALUE obj, VALUE num)
 {
     char buf[128];
-    sprintf(buf, "%d", NUM2SHORT(num));
+    snprintf(buf, sizeof(buf), "%d", NUM2SHORT(num));
     return rb_str_new_cstr(buf);
 }
 
@@ -12,7 +12,7 @@ static VALUE
 test_num2ushort(VALUE obj, VALUE num)
 {
     char buf[128];
-    sprintf(buf, "%u", NUM2USHORT(num));
+    snprintf(buf, sizeof(buf), "%u", NUM2USHORT(num));
     return rb_str_new_cstr(buf);
 }
 
@@ -20,7 +20,7 @@ static VALUE
 test_num2int(VALUE obj, VALUE num)
 {
     char buf[128];
-    sprintf(buf, "%d", NUM2INT(num));
+    snprintf(buf, sizeof(buf), "%d", NUM2INT(num));
     return rb_str_new_cstr(buf);
 }
 
@@ -28,7 +28,7 @@ static VALUE
 test_num2uint(VALUE obj, VALUE num)
 {
     char buf[128];
-    sprintf(buf, "%u", NUM2UINT(num));
+    snprintf(buf, sizeof(buf), "%u", NUM2UINT(num));
     return rb_str_new_cstr(buf);
 }
 
@@ -36,7 +36,7 @@ static VALUE
 test_num2long(VALUE obj, VALUE num)
 {
     char buf[128];
-    sprintf(buf, "%ld", NUM2LONG(num));
+    snprintf(buf, sizeof(buf), "%ld", NUM2LONG(num));
     return rb_str_new_cstr(buf);
 }
 
@@ -44,7 +44,7 @@ static VALUE
 test_num2ulong(VALUE obj, VALUE num)
 {
     char buf[128];
-    sprintf(buf, "%lu", NUM2ULONG(num));
+    snprintf(buf, sizeof(buf), "%lu", NUM2ULONG(num));
     return rb_str_new_cstr(buf);
 }
 
@@ -53,7 +53,7 @@ static VALUE
 test_num2ll(VALUE obj, VALUE num)
 {
     char buf[128];
-    sprintf(buf, "%"PRI_LL_PREFIX"d", NUM2LL(num));
+    snprintf(buf, sizeof(buf), "%"PRI_LL_PREFIX"d", NUM2LL(num));
     return rb_str_new_cstr(buf);
 }
 
@@ -61,7 +61,7 @@ static VALUE
 test_num2ull(VALUE obj, VALUE num)
 {
     char buf[128];
-    sprintf(buf, "%"PRI_LL_PREFIX"u", NUM2ULL(num));
+    snprintf(buf, sizeof(buf), "%"PRI_LL_PREFIX"u", NUM2ULL(num));
     return rb_str_new_cstr(buf);
 }
 #endif
@@ -70,7 +70,7 @@ static VALUE
 test_fix2short(VALUE obj, VALUE num)
 {
     char buf[128];
-    sprintf(buf, "%d", FIX2SHORT(num));
+    snprintf(buf, sizeof(buf), "%d", FIX2SHORT(num));
     return rb_str_new_cstr(buf);
 }
 
@@ -78,7 +78,7 @@ static VALUE
 test_fix2int(VALUE obj, VALUE num)
 {
     char buf[128];
-    sprintf(buf, "%d", FIX2INT(num));
+    snprintf(buf, sizeof(buf), "%d", FIX2INT(num));
     return rb_str_new_cstr(buf);
 }
 
@@ -86,7 +86,7 @@ static VALUE
 test_fix2uint(VALUE obj, VALUE num)
 {
     char buf[128];
-    sprintf(buf, "%u", FIX2UINT(num));
+    snprintf(buf, sizeof(buf), "%u", FIX2UINT(num));
     return rb_str_new_cstr(buf);
 }
 
@@ -94,7 +94,7 @@ static VALUE
 test_fix2long(VALUE obj, VALUE num)
 {
     char buf[128];
-    sprintf(buf, "%ld", FIX2LONG(num));
+    snprintf(buf, sizeof(buf), "%ld", FIX2LONG(num));
     return rb_str_new_cstr(buf);
 }
 
@@ -102,7 +102,7 @@ static VALUE
 test_fix2ulong(VALUE obj, VALUE num)
 {
     char buf[128];
-    sprintf(buf, "%lu", FIX2ULONG(num));
+    snprintf(buf, sizeof(buf), "%lu", FIX2ULONG(num));
     return rb_str_new_cstr(buf);
 }
 
diff --git a/ext/-test-/printf/printf.c b/ext/-test-/printf/printf.c
index e793bb7a48..889c0d9f0d 100644
--- a/ext/-test-/printf/printf.c
+++ b/ext/-test-/printf/printf.c
@@ -25,7 +25,7 @@ uint_to_str(char *p, char *e, unsigned int x)
     char *e0 = e;
     if (e <= p) return p;
     do {
-	*--e = x % 10 + '0';
+        *--e = x % 10 + '0';
     } while ((x /= 10) != 0 && e > p);
     memmove(p, e, e0 - e);
     return p + (e0 - e);
@@ -44,48 +44,48 @@ printf_test_call(int argc, VALUE *argv, VALUE self)
     if (RSTRING_LEN(type) != 1) rb_raise(rb_eArgError, "wrong length(%ld)", RSTRING_LEN(type));
     switch (cnv = RSTRING_PTR(type)[0]) {
       case 'd': case 'x': case 'o': case 'X':
-	n = NUM2INT(num);
-	break;
+        n = NUM2INT(num);
+        break;
       case 's':
-	s = StringValueCStr(num);
-	break;
+        s = StringValueCStr(num);
+        break;
       default: rb_raise(rb_eArgError, "wrong conversion(%c)", cnv);
     }
     *p++ = '%';
     if (!NIL_P(opt)) {
-	VALUE v;
-	Check_Type(opt, T_HASH);
-	if (RTEST(rb_hash_aref(opt, ID2SYM(rb_intern("space"))))) {
-	    *p++ = ' ';
-	}
-	if (RTEST(rb_hash_aref(opt, ID2SYM(rb_intern("hash"))))) {
-	    *p++ = '#';
-	}
-	if (RTEST(rb_hash_aref(opt, ID2SYM(rb_intern("plus"))))) {
-	    *p++ = '+';
-	}
-	if (RTEST(rb_hash_aref(opt, ID2SYM(rb_intern("minus"))))) {
-	    *p++ = '-';
-	}
-	if (RTEST(rb_hash_aref(opt, ID2SYM(rb_intern("zero"))))) {
-	    *p++ = '0';
-	}
-	if (!NIL_P(v = rb_hash_aref(opt, ID2SYM(rb_intern("width"))))) {
-	    p = uint_to_str(p, format + sizeof(format), NUM2UINT(v));
-	}
-	if (!NIL_P(v = rb_hash_aref(opt, ID2SYM(rb_intern("prec"))))) {
-	    *p++ = '.';
-	    if (FIXNUM_P(v))
-		p = uint_to_str(p, format + sizeof(format), NUM2UINT(v));
-	}
+        VALUE v;
+        Check_Type(opt, T_HASH);
+        if (RTEST(rb_hash_aref(opt, ID2SYM(rb_intern("space"))))) {
+            *p++ = ' ';
+        }
+        if (RTEST(rb_hash_aref(opt, ID2SYM(rb_intern("hash"))))) {
+            *p++ = '#';
+        }
+        if (RTEST(rb_hash_aref(opt, ID2SYM(rb_intern("plus"))))) {
+            *p++ = '+';
+        }
+        if (RTEST(rb_hash_aref(opt, ID2SYM(rb_intern("minus"))))) {
+            *p++ = '-';
+        }
+        if (RTEST(rb_hash_aref(opt, ID2SYM(rb_intern("zero"))))) {
+            *p++ = '0';
+        }
+        if (!NIL_P(v = rb_hash_aref(opt, ID2SYM(rb_intern("width"))))) {
+            p = uint_to_str(p, format + sizeof(format), NUM2UINT(v));
+        }
+        if (!NIL_P(v = rb_hash_aref(opt, ID2SYM(rb_intern("prec"))))) {
+            *p++ = '.';
+            if (FIXNUM_P(v))
+                p = uint_to_str(p, format + sizeof(format), NUM2UINT(v));
+        }
     }
     *p++ = cnv;
     *p++ = '\0';
     if (cnv == 's') {
-	result = rb_enc_sprintf(rb_usascii_encoding(), format, s);
+        result = rb_enc_sprintf(rb_usascii_encoding(), format, s);
     }
     else {
-	result = rb_enc_sprintf(rb_usascii_encoding(), format, n);
+        result = rb_enc_sprintf(rb_usascii_encoding(), format, n);
     }
     return rb_assoc_new(result, rb_usascii_str_new_cstr(format));
 }
diff --git a/ext/-test-/proc/super.c b/ext/-test-/proc/super.c
index dbe8af08f1..816520e1df 100644
--- a/ext/-test-/proc/super.c
+++ b/ext/-test-/proc/super.c
@@ -9,7 +9,7 @@ bug_proc_call_super(RB_BLOCK_CALL_FUNC_ARGLIST(yieldarg, procarg))
     args[1] = procarg;
     ret = rb_call_super(2, args);
     if (!NIL_P(blockarg)) {
-	ret = rb_proc_call(blockarg, ret);
+        ret = rb_proc_call(blockarg, ret);
     }
     return ret;
 }
diff --git a/ext/-test-/random/bad_version.c b/ext/-test-/random/bad_version.c
new file mode 100644
index 0000000000..dae63a6d19
--- /dev/null
+++ b/ext/-test-/random/bad_version.c
@@ -0,0 +1,135 @@
+#include "ruby/random.h"
+
+#if RUBY_RANDOM_INTERFACE_VERSION_MAJOR < RUBY_RANDOM_INTERFACE_VERSION_MAJOR_MAX
+# define DEFINE_VERSION_MAX 1
+#else
+# define DEFINE_VERSION_MAX 0
+#endif
+
+NORETURN(static void must_not_reach(void));
+static void
+must_not_reach(void)
+{
+    rb_raise(rb_eTypeError, "must not reach");
+}
+
+NORETURN(static void bad_version_init(rb_random_t *, const uint32_t *, size_t));
+static void
+bad_version_init(rb_random_t *rnd, const uint32_t *buf, size_t len)
+{
+    must_not_reach();
+}
+
+NORETURN(static void bad_version_init_int32(rb_random_t *, uint32_t));
+RB_RANDOM_DEFINE_INIT_INT32_FUNC(bad_version)
+
+NORETURN(static void bad_version_get_bytes(rb_random_t *, void *, size_t));
+static void
+bad_version_get_bytes(rb_random_t *rnd, void *p, size_t n)
+{
+    must_not_reach();
+}
+
+NORETURN(static uint32_t bad_version_get_int32(rb_random_t *));
+static uint32_t
+bad_version_get_int32(rb_random_t *rnd)
+{
+    must_not_reach();
+    UNREACHABLE_RETURN(0);
+}
+
+static VALUE
+bad_version_alloc(VALUE klass, const rb_data_type_t *type)
+{
+    rb_random_t *rnd;
+    VALUE obj = TypedData_Make_Struct(klass, rb_random_t, type, rnd);
+    rb_random_base_init(rnd);
+    return obj;
+}
+
+/* version 0 */
+static const rb_random_interface_t random_version_zero_if;
+
+static rb_random_data_type_t version_zero_type = {
+    "random/version_zero",
+    {
+        rb_random_mark,
+        RUBY_TYPED_DEFAULT_FREE,
+    },
+    RB_RANDOM_PARENT,
+    (void *)&random_version_zero_if,
+    RUBY_TYPED_FREE_IMMEDIATELY
+};
+
+static VALUE
+version_zero_alloc(VALUE klass)
+{
+    return bad_version_alloc(klass, &version_zero_type);
+}
+
+static void
+init_version_zero(VALUE mod, VALUE base)
+{
+    VALUE c = rb_define_class_under(mod, "VersionZero", base);
+    rb_define_alloc_func(c, version_zero_alloc);
+    RB_RANDOM_DATA_INIT_PARENT(version_zero_type);
+}
+
+#if DEFINE_VERSION_MAX
+/* version max */
+static const rb_random_interface_t random_version_max_if;
+static rb_random_data_type_t version_max_type = {
+    "random/version_max",
+    {
+        rb_random_mark,
+        RUBY_TYPED_DEFAULT_FREE,
+    },
+    RB_RANDOM_PARENT,
+    (void *)&random_version_max_if,
+    RUBY_TYPED_FREE_IMMEDIATELY
+};
+
+static VALUE
+version_max_alloc(VALUE klass)
+{
+    return bad_version_alloc(klass, &version_max_type);
+}
+
+static void
+init_version_max(VALUE mod, VALUE base)
+{
+    VALUE c = rb_define_class_under(mod, "VersionMax", base);
+    rb_define_alloc_func(c, version_max_alloc);
+    RB_RANDOM_DATA_INIT_PARENT(version_max_type);
+}
+#else
+static void
+init_version_max(mod, base)
+{
+}
+#endif
+
+void
+Init_random_bad_version(VALUE mod, VALUE base)
+{
+    init_version_zero(mod, base);
+    init_version_max(mod, base);
+}
+
+#undef RUBY_RANDOM_INTERFACE_VERSION_MAJOR
+
+#define RUBY_RANDOM_INTERFACE_VERSION_MAJOR 0
+static const rb_random_interface_t random_version_zero_if = {
+    0,
+    RB_RANDOM_INTERFACE_DEFINE(bad_version)
+};
+#undef RUBY_RANDOM_INTERFACE_VERSION_MAJOR
+
+#if DEFINE_VERSION_MAX
+#define RUBY_RANDOM_INTERFACE_VERSION_MAJOR RUBY_RANDOM_INTERFACE_VERSION_MAJOR_MAX
+static const rb_random_interface_t random_version_max_if = {
+    0,
+    RB_RANDOM_INTERFACE_DEFINE(bad_version)
+};
+#undef RUBY_RANDOM_INTERFACE_VERSION_MAJOR
+#endif
diff --git a/ext/-test-/random/depend b/ext/-test-/random/depend
index 602526cf7b..f2cbf7fc14 100644
--- a/ext/-test-/random/depend
+++ b/ext/-test-/random/depend
@@ -1,4 +1,164 @@
 # AUTOGENERATED DEPENDENCIES START
+bad_version.o: $(RUBY_EXTCONF_H)
+bad_version.o: $(arch_hdrdir)/ruby/config.h
+bad_version.o: $(hdrdir)/ruby/assert.h
+bad_version.o: $(hdrdir)/ruby/backward.h
+bad_version.o: $(hdrdir)/ruby/backward/2/assume.h
+bad_version.o: $(hdrdir)/ruby/backward/2/attributes.h
+bad_version.o: $(hdrdir)/ruby/backward/2/bool.h
+bad_version.o: $(hdrdir)/ruby/backward/2/inttypes.h
+bad_version.o: $(hdrdir)/ruby/backward/2/limits.h
+bad_version.o: $(hdrdir)/ruby/backward/2/long_long.h
+bad_version.o: $(hdrdir)/ruby/backward/2/stdalign.h
+bad_version.o: $(hdrdir)/ruby/backward/2/stdarg.h
+bad_version.o: $(hdrdir)/ruby/defines.h
+bad_version.o: $(hdrdir)/ruby/intern.h
+bad_version.o: $(hdrdir)/ruby/internal/abi.h
+bad_version.o: $(hdrdir)/ruby/internal/anyargs.h
+bad_version.o: $(hdrdir)/ruby/internal/arithmetic.h
+bad_version.o: $(hdrdir)/ruby/internal/arithmetic/char.h
+bad_version.o: $(hdrdir)/ruby/internal/arithmetic/double.h
+bad_version.o: $(hdrdir)/ruby/internal/arithmetic/fixnum.h
+bad_version.o: $(hdrdir)/ruby/internal/arithmetic/gid_t.h
+bad_version.o: $(hdrdir)/ruby/internal/arithmetic/int.h
+bad_version.o: $(hdrdir)/ruby/internal/arithmetic/intptr_t.h
+bad_version.o: $(hdrdir)/ruby/internal/arithmetic/long.h
+bad_version.o: $(hdrdir)/ruby/internal/arithmetic/long_long.h
+bad_version.o: $(hdrdir)/ruby/internal/arithmetic/mode_t.h
+bad_version.o: $(hdrdir)/ruby/internal/arithmetic/off_t.h
+bad_version.o: $(hdrdir)/ruby/internal/arithmetic/pid_t.h
+bad_version.o: $(hdrdir)/ruby/internal/arithmetic/short.h
+bad_version.o: $(hdrdir)/ruby/internal/arithmetic/size_t.h
+bad_version.o: $(hdrdir)/ruby/internal/arithmetic/st_data_t.h
+bad_version.o: $(hdrdir)/ruby/internal/arithmetic/uid_t.h
+bad_version.o: $(hdrdir)/ruby/internal/assume.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/alloc_size.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/artificial.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/cold.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/const.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/constexpr.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/deprecated.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/diagnose_if.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/enum_extensibility.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/error.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/flag_enum.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/forceinline.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/format.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/maybe_unused.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/noalias.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/nodiscard.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/noexcept.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/noinline.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/nonnull.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/noreturn.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/pure.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/restrict.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/returns_nonnull.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/warning.h
+bad_version.o: $(hdrdir)/ruby/internal/attr/weakref.h
+bad_version.o: $(hdrdir)/ruby/internal/cast.h
+bad_version.o: $(hdrdir)/ruby/internal/compiler_is.h
+bad_version.o: $(hdrdir)/ruby/internal/compiler_is/apple.h
+bad_version.o: $(hdrdir)/ruby/internal/compiler_is/clang.h
+bad_version.o: $(hdrdir)/ruby/internal/compiler_is/gcc.h
+bad_version.o: $(hdrdir)/ruby/internal/compiler_is/intel.h
+bad_version.o: $(hdrdir)/ruby/internal/compiler_is/msvc.h
+bad_version.o: $(hdrdir)/ruby/internal/compiler_is/sunpro.h
+bad_version.o: $(hdrdir)/ruby/internal/compiler_since.h
+bad_version.o: $(hdrdir)/ruby/internal/config.h
+bad_version.o: $(hdrdir)/ruby/internal/constant_p.h
+bad_version.o: $(hdrdir)/ruby/internal/core.h
+bad_version.o: $(hdrdir)/ruby/internal/core/rarray.h
+bad_version.o: $(hdrdir)/ruby/internal/core/rbasic.h
+bad_version.o: $(hdrdir)/ruby/internal/core/rbignum.h
+bad_version.o: $(hdrdir)/ruby/internal/core/rclass.h
+bad_version.o: $(hdrdir)/ruby/internal/core/rdata.h
+bad_version.o: $(hdrdir)/ruby/internal/core/rfile.h
+bad_version.o: $(hdrdir)/ruby/internal/core/rhash.h
+bad_version.o: $(hdrdir)/ruby/internal/core/robject.h
+bad_version.o: $(hdrdir)/ruby/internal/core/rregexp.h
+bad_version.o: $(hdrdir)/ruby/internal/core/rstring.h
+bad_version.o: $(hdrdir)/ruby/internal/core/rstruct.h
+bad_version.o: $(hdrdir)/ruby/internal/core/rtypeddata.h
+bad_version.o: $(hdrdir)/ruby/internal/ctype.h
+bad_version.o: $(hdrdir)/ruby/internal/dllexport.h
+bad_version.o: $(hdrdir)/ruby/internal/dosish.h
+bad_version.o: $(hdrdir)/ruby/internal/error.h
+bad_version.o: $(hdrdir)/ruby/internal/eval.h
+bad_version.o: $(hdrdir)/ruby/internal/event.h
+bad_version.o: $(hdrdir)/ruby/internal/fl_type.h
+bad_version.o: $(hdrdir)/ruby/internal/gc.h
+bad_version.o: $(hdrdir)/ruby/internal/glob.h
+bad_version.o: $(hdrdir)/ruby/internal/globals.h
+bad_version.o: $(hdrdir)/ruby/internal/has/attribute.h
+bad_version.o: $(hdrdir)/ruby/internal/has/builtin.h
+bad_version.o: $(hdrdir)/ruby/internal/has/c_attribute.h
+bad_version.o: $(hdrdir)/ruby/internal/has/cpp_attribute.h
+bad_version.o: $(hdrdir)/ruby/internal/has/declspec_attribute.h
+bad_version.o: $(hdrdir)/ruby/internal/has/extension.h
+bad_version.o: $(hdrdir)/ruby/internal/has/feature.h
+bad_version.o: $(hdrdir)/ruby/internal/has/warning.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/array.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/bignum.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/class.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/compar.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/complex.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/cont.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/dir.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/enum.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/enumerator.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/error.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/eval.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/file.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/gc.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/hash.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/io.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/load.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/marshal.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/numeric.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/object.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/parse.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/proc.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/process.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/random.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/range.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/rational.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/re.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/ruby.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/select.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/select/largesize.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/signal.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/sprintf.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/string.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/struct.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/thread.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/time.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/variable.h
+bad_version.o: $(hdrdir)/ruby/internal/intern/vm.h
+bad_version.o: $(hdrdir)/ruby/internal/interpreter.h
+bad_version.o: $(hdrdir)/ruby/internal/iterator.h
+bad_version.o: $(hdrdir)/ruby/internal/memory.h
+bad_version.o: $(hdrdir)/ruby/internal/method.h
+bad_version.o: $(hdrdir)/ruby/internal/module.h
+bad_version.o: $(hdrdir)/ruby/internal/newobj.h
+bad_version.o: $(hdrdir)/ruby/internal/rgengc.h
+bad_version.o: $(hdrdir)/ruby/internal/scan_args.h
+bad_version.o: $(hdrdir)/ruby/internal/special_consts.h
+bad_version.o: $(hdrdir)/ruby/internal/static_assert.h
+bad_version.o: $(hdrdir)/ruby/internal/stdalign.h
+bad_version.o: $(hdrdir)/ruby/internal/stdbool.h
+bad_version.o: $(hdrdir)/ruby/internal/symbol.h
+bad_version.o: $(hdrdir)/ruby/internal/value.h
+bad_version.o: $(hdrdir)/ruby/internal/value_type.h
+bad_version.o: $(hdrdir)/ruby/internal/variable.h
+bad_version.o: $(hdrdir)/ruby/internal/warning_push.h
+bad_version.o: $(hdrdir)/ruby/internal/xmalloc.h
+bad_version.o: $(hdrdir)/ruby/missing.h
+bad_version.o: $(hdrdir)/ruby/random.h
+bad_version.o: $(hdrdir)/ruby/ruby.h
+bad_version.o: $(hdrdir)/ruby/st.h
+bad_version.o: $(hdrdir)/ruby/subst.h
+bad_version.o: bad_version.c
 init.o: $(RUBY_EXTCONF_H)
 init.o: $(arch_hdrdir)/ruby/config.h
 init.o: $(hdrdir)/ruby.h
diff --git a/ext/-test-/random/loop.c b/ext/-test-/random/loop.c
index 0572096403..b789ab1d01 100644
--- a/ext/-test-/random/loop.c
+++ b/ext/-test-/random/loop.c
@@ -13,6 +13,7 @@ static const rb_random_interface_t random_loop_if = {
     RB_RANDOM_INTERFACE_DEFINE_WITH_REAL(loop)
 };
 
+RB_RANDOM_DEFINE_INIT_INT32_FUNC(loop)
 static size_t
 random_loop_memsize(const void *ptr)
 {
diff --git a/ext/-test-/rational/depend b/ext/-test-/rational/depend
index 8729695886..ce977821b8 100644
--- a/ext/-test-/rational/depend
+++ b/ext/-test-/rational/depend
@@ -174,5 +174,6 @@ rat.o: $(top_srcdir)/internal/static_assert.h
 rat.o: $(top_srcdir)/internal/vm.h
 rat.o: $(top_srcdir)/internal/warnings.h
 rat.o: $(top_srcdir)/ruby_assert.h
+rat.o: $(top_srcdir)/shape.h
 rat.o: rat.c
 # AUTOGENERATED DEPENDENCIES END
diff --git a/ext/-test-/rb_call_super_kw/rb_call_super_kw.c b/ext/-test-/rb_call_super_kw/rb_call_super_kw.c
index 7f094545d2..61681ed733 100644
--- a/ext/-test-/rb_call_super_kw/rb_call_super_kw.c
+++ b/ext/-test-/rb_call_super_kw/rb_call_super_kw.c
@@ -7,7 +7,8 @@ rb_call_super_kw_m(int argc, VALUE *argv, VALUE self)
 }
 
 void
-Init_rb_call_super_kw(void) {
+Init_rb_call_super_kw(void)
+{
     VALUE module = rb_define_module("Bug");
     module = rb_define_module_under(module, "RbCallSuperKw");
     rb_define_method(module, "m", rb_call_super_kw_m, -1);
diff --git a/ext/-test-/st/foreach/foreach.c b/ext/-test-/st/foreach/foreach.c
index 27ac18046f..cde49fb26d 100644
--- a/ext/-test-/st/foreach/foreach.c
+++ b/ext/-test-/st/foreach/foreach.c
@@ -12,22 +12,22 @@ static void
 force_unpack_check(struct checker *c, st_data_t key, st_data_t val)
 {
     if (c->nr == 0) {
-	st_data_t i;
+        st_data_t i;
 
-	if (c->tbl->bins != NULL) rb_bug("should be packed\n");
+        if (c->tbl->bins != NULL) rb_bug("should be packed\n");
 
-	/* force unpacking during iteration: */
-	for (i = 1; i < expect_size; i++)
-	    st_add_direct(c->tbl, i, i);
+        /* force unpacking during iteration: */
+        for (i = 1; i < expect_size; i++)
+            st_add_direct(c->tbl, i, i);
 
-	if (c->tbl->bins == NULL) rb_bug("should be unpacked\n");
+        if (c->tbl->bins == NULL) rb_bug("should be unpacked\n");
     }
 
     if (key != c->nr) {
-	rb_bug("unexpected key: %"PRIuVALUE" (expected %"PRIuVALUE")\n", (VALUE)key, (VALUE)c->nr);
+        rb_bug("unexpected key: %"PRIuVALUE" (expected %"PRIuVALUE")\n", (VALUE)key, (VALUE)c->nr);
     }
     if (val != c->nr) {
-	rb_bug("unexpected val: %"PRIuVALUE" (expected %"PRIuVALUE")\n", (VALUE)val, (VALUE)c->nr);
+        rb_bug("unexpected val: %"PRIuVALUE" (expected %"PRIuVALUE")\n", (VALUE)val, (VALUE)c->nr);
     }
 
     c->nr++;
@@ -39,34 +39,34 @@ unp_fec_i(st_data_t key, st_data_t val, st_data_t args, int error)
     struct checker *c = (struct checker *)args;
 
     if (error) {
-	if (c->test == ID2SYM(rb_intern("delete2")))
-	    return ST_STOP;
+        if (c->test == ID2SYM(rb_intern("delete2")))
+            return ST_STOP;
 
-	rb_bug("unexpected error");
+        rb_bug("unexpected error");
     }
 
     force_unpack_check(c, key, val);
 
     if (c->test == ID2SYM(rb_intern("check"))) {
-	return ST_CHECK;
+        return ST_CHECK;
     }
     if (c->test == ID2SYM(rb_intern("delete1"))) {
-	if (c->nr == 1) return ST_DELETE;
-	return ST_CHECK;
+        if (c->nr == 1) return ST_DELETE;
+        return ST_CHECK;
     }
     if (c->test == ID2SYM(rb_intern("delete2"))) {
-	if (c->nr == 1) {
-	    st_data_t k = 0;
-	    st_data_t v;
-
-	    if (!st_delete(c->tbl, &k, &v)) {
-		rb_bug("failed to delete\n");
-	    }
-	    if (v != 0) {
-		rb_bug("unexpected value deleted: %"PRIuVALUE" (expected 0)", (VALUE)v);
-	    }
-	}
-	return ST_CHECK;
+        if (c->nr == 1) {
+            st_data_t k = 0;
+            st_data_t v;
+
+            if (!st_delete(c->tbl, &k, &v)) {
+                rb_bug("failed to delete\n");
+            }
+            if (v != 0) {
+                rb_bug("unexpected value deleted: %"PRIuVALUE" (expected 0)", (VALUE)v);
+            }
+        }
+        return ST_CHECK;
     }
 
     rb_raise(rb_eArgError, "unexpected arg: %+"PRIsVALUE, c->test);
@@ -89,13 +89,13 @@ unp_fec(VALUE self, VALUE test)
     st_foreach_check(tbl, unp_fec_i, (st_data_t)&c, -1);
 
     if (c.test == ID2SYM(rb_intern("delete2"))) {
-	if (c.nr != 1) {
-	    rb_bug("mismatched iteration: %"PRIuVALUE" (expected 1)\n", (VALUE)c.nr);
-	}
+        if (c.nr != 1) {
+            rb_bug("mismatched iteration: %"PRIuVALUE" (expected 1)\n", (VALUE)c.nr);
+        }
     }
     else if (c.nr != expect_size) {
-	rb_bug("mismatched iteration: %"PRIuVALUE" (expected %"PRIuVALUE")\n",
-		(VALUE)c.nr, (VALUE)expect_size);
+        rb_bug("mismatched iteration: %"PRIuVALUE" (expected %"PRIuVALUE")\n",
+                (VALUE)c.nr, (VALUE)expect_size);
     }
 
     if (tbl->bins == NULL) rb_bug("should be unpacked\n");
@@ -112,22 +112,22 @@ unp_fe_i(st_data_t key, st_data_t val, st_data_t args)
 
     force_unpack_check(c, key, val);
     if (c->test == ID2SYM(rb_intern("unpacked"))) {
-	return ST_CONTINUE;
+        return ST_CONTINUE;
     }
     else if (c->test == ID2SYM(rb_intern("unpack_delete"))) {
-	if (c->nr == 1) {
-	    st_data_t k = 0;
-	    st_data_t v;
-
-	    if (!st_delete(c->tbl, &k, &v)) {
-		rb_bug("failed to delete\n");
-	    }
-	    if (v != 0) {
-		rb_bug("unexpected value deleted: %"PRIuVALUE" (expected 0)", (VALUE)v);
-	    }
-	    return ST_CONTINUE;
-	}
-	rb_bug("should never get here\n");
+        if (c->nr == 1) {
+            st_data_t k = 0;
+            st_data_t v;
+
+            if (!st_delete(c->tbl, &k, &v)) {
+                rb_bug("failed to delete\n");
+            }
+            if (v != 0) {
+                rb_bug("unexpected value deleted: %"PRIuVALUE" (expected 0)", (VALUE)v);
+            }
+            return ST_CONTINUE;
+        }
+        rb_bug("should never get here\n");
     }
 
     rb_raise(rb_eArgError, "unexpected arg: %+"PRIsVALUE, c->test);
@@ -150,13 +150,13 @@ unp_fe(VALUE self, VALUE test)
     st_foreach(tbl, unp_fe_i, (st_data_t)&c);
 
     if (c.test == ID2SYM(rb_intern("unpack_delete"))) {
-	if (c.nr != 1) {
-	    rb_bug("mismatched iteration: %"PRIuVALUE" (expected 1)\n", (VALUE)c.nr);
-	}
+        if (c.nr != 1) {
+            rb_bug("mismatched iteration: %"PRIuVALUE" (expected 1)\n", (VALUE)c.nr);
+        }
     }
     else if (c.nr != expect_size) {
-	rb_bug("mismatched iteration: %"PRIuVALUE" (expected %"PRIuVALUE"o)\n",
-		(VALUE)c.nr, (VALUE)expect_size);
+        rb_bug("mismatched iteration: %"PRIuVALUE" (expected %"PRIuVALUE"o)\n",
+                (VALUE)c.nr, (VALUE)expect_size);
     }
 
     if (tbl->bins == NULL) rb_bug("should be unpacked\n");
diff --git a/ext/-test-/st/numhash/numhash.c b/ext/-test-/st/numhash/numhash.c
index aa8015e86c..7e8d5d9fe2 100644
--- a/ext/-test-/st/numhash/numhash.c
+++ b/ext/-test-/st/numhash/numhash.c
@@ -42,7 +42,7 @@ numhash_aref(VALUE self, VALUE key)
     st_table *tbl = (st_table *)Check_TypedStruct(self, &numhash_type);
     if (!SPECIAL_CONST_P(key)) rb_raise(rb_eArgError, "not a special const");
     if (st_lookup(tbl, (st_data_t)key, &data))
-	return (VALUE)data;
+        return (VALUE)data;
     return Qnil;
 }
 
@@ -79,12 +79,12 @@ update_func(st_data_t *key, st_data_t *value, st_data_t arg, int existing)
     VALUE ret = rb_yield_values(existing ? 2 : 1, (VALUE)*key, (VALUE)*value);
     switch (ret) {
       case Qfalse:
-	return ST_STOP;
+        return ST_STOP;
       case Qnil:
-	return ST_DELETE;
+        return ST_DELETE;
       default:
-	*value = ret;
-	return ST_CONTINUE;
+        *value = ret;
+        return ST_CONTINUE;
     }
 }
 
@@ -93,9 +93,9 @@ numhash_update(VALUE self, VALUE key)
 {
     st_table *table = (st_table *)Check_TypedStruct(self, &numhash_type);
     if (st_update(table, (st_data_t)key, update_func, 0))
-	return Qtrue;
+        return Qtrue;
     else
-	return Qfalse;
+        return Qfalse;
 }
 
 #if SIZEOF_LONG == SIZEOF_VOIDP
@@ -117,7 +117,7 @@ numhash_delete_safe(VALUE self, VALUE key)
     st_table *table = (st_table *)Check_TypedStruct(self, &numhash_type);
     st_data_t val, k = (st_data_t)key;
     if (st_delete_safe(table, &k, &val, (st_data_t)self)) {
-	return val;
+        return val;
     }
     return Qnil;
 }
diff --git a/ext/-test-/st/update/update.c b/ext/-test-/st/update/update.c
index 979ad3e334..ea7fab12e1 100644
--- a/ext/-test-/st/update/update.c
+++ b/ext/-test-/st/update/update.c
@@ -7,12 +7,12 @@ update_func(st_data_t *key, st_data_t *value, st_data_t arg, int existing)
     VALUE ret = rb_yield_values(existing ? 2 : 1, (VALUE)*key, (VALUE)*value);
     switch (ret) {
       case Qfalse:
-	return ST_STOP;
+        return ST_STOP;
       case Qnil:
-	return ST_DELETE;
+        return ST_DELETE;
       default:
-	*value = ret;
-	return ST_CONTINUE;
+        *value = ret;
+        return ST_CONTINUE;
     }
 }
 
@@ -20,9 +20,9 @@ static VALUE
 test_st_update(VALUE self, VALUE key)
 {
     if (st_update(RHASH_TBL(self), (st_data_t)key, update_func, 0))
-	return Qtrue;
+        return Qtrue;
     else
-	return Qfalse;
+        return Qfalse;
 }
 
 void
diff --git a/ext/-test-/string/coderange.c b/ext/-test-/string/coderange.c
index bc998ca372..4197ecca9f 100644
--- a/ext/-test-/string/coderange.c
+++ b/ext/-test-/string/coderange.c
@@ -8,13 +8,13 @@ coderange_int2sym(int coderange)
 {
     switch (coderange) {
       case ENC_CODERANGE_7BIT:
-	return sym_7bit;
+        return sym_7bit;
       case ENC_CODERANGE_VALID:
-	return sym_valid;
+        return sym_valid;
       case ENC_CODERANGE_UNKNOWN:
-	return sym_unknown;
+        return sym_unknown;
       case ENC_CODERANGE_BROKEN:
-	return sym_broken;
+        return sym_broken;
     }
     rb_bug("wrong condition of coderange");
     UNREACHABLE_RETURN(Qnil);
diff --git a/ext/-test-/string/cstr.c b/ext/-test-/string/cstr.c
index 1eadb8b4fd..468ee7a3b1 100644
--- a/ext/-test-/string/cstr.c
+++ b/ext/-test-/string/cstr.c
@@ -42,11 +42,11 @@ bug_str_cstr_term_char(VALUE str)
     len = rb_enc_mbminlen(enc);
     c = rb_enc_precise_mbclen(s, s + len, enc);
     if (!MBCLEN_CHARFOUND_P(c)) {
-	c = (unsigned char)*s;
+        c = (unsigned char)*s;
     }
     else {
-	c = rb_enc_mbc_to_codepoint(s, s + len, enc);
-	if (!c) return Qnil;
+        c = rb_enc_mbc_to_codepoint(s, s + len, enc);
+        if (!c) return Qnil;
     }
     return rb_enc_uint_chr((unsigned int)c, enc);
 }
@@ -65,14 +65,14 @@ bug_str_unterminated_substring(VALUE str, VALUE vbeg, VALUE vlen)
 #if USE_RVARGC
         RSTRING(str)->as.embed.len = (short)len;
 #else
-	RSTRING(str)->basic.flags &= ~RSTRING_EMBED_LEN_MASK;
-	RSTRING(str)->basic.flags |= len << RSTRING_EMBED_LEN_SHIFT;
+        RSTRING(str)->basic.flags &= ~RSTRING_EMBED_LEN_MASK;
+        RSTRING(str)->basic.flags |= len << RSTRING_EMBED_LEN_SHIFT;
 #endif
         memmove(RSTRING(str)->as.embed.ary, RSTRING(str)->as.embed.ary + beg, len);
     }
     else {
-	RSTRING(str)->as.heap.ptr += beg;
-	RSTRING(str)->as.heap.len = len;
+        RSTRING(str)->as.heap.ptr += beg;
+        RSTRING(str)->as.heap.len = len;
     }
     return str;
 }
@@ -104,7 +104,7 @@ bug_str_s_cstr_term_char(VALUE self, VALUE str)
     const int term_fill_len = (termlen);\
     *term_fill_ptr = '\0';\
     if (UNLIKELY(term_fill_len > 1))\
-	memset(term_fill_ptr, 0, term_fill_len);\
+        memset(term_fill_ptr, 0, term_fill_len);\
 } while (0)
 
 static VALUE
diff --git a/ext/-test-/string/fstring.c b/ext/-test-/string/fstring.c
index 2374319fe3..64f079251d 100644
--- a/ext/-test-/string/fstring.c
+++ b/ext/-test-/string/fstring.c
@@ -12,13 +12,13 @@ bug_s_fstring(VALUE self, VALUE str)
 VALUE
 bug_s_rb_enc_interned_str(VALUE self, VALUE encoding)
 {
-    return rb_enc_interned_str("foo", 3, RDATA(encoding)->data);
+    return rb_enc_interned_str("foo", 3, NIL_P(encoding) ? NULL : RDATA(encoding)->data);
 }
 
 VALUE
 bug_s_rb_enc_str_new(VALUE self, VALUE encoding)
 {
-    return rb_enc_str_new("foo", 3, RDATA(encoding)->data);
+    return rb_enc_str_new("foo", 3, NIL_P(encoding) ? NULL : RDATA(encoding)->data);
 }
 
 void
diff --git a/ext/-test-/string/qsort.c b/ext/-test-/string/qsort.c
index fb7ea3d8cb..4a641e74e3 100644
--- a/ext/-test-/string/qsort.c
+++ b/ext/-test-/string/qsort.c
@@ -35,22 +35,22 @@ bug_str_qsort_bang(int argc, VALUE *argv, VALUE str)
     rb_scan_args(argc, argv, "03", &beg, &len, &size);
     l = RSTRING_LEN(str);
     if (!NIL_P(beg) && (b = NUM2INT(beg)) < 0 && (b += l) < 0) {
-	rb_raise(rb_eArgError, "out of bounds");
+        rb_raise(rb_eArgError, "out of bounds");
     }
     if (!NIL_P(size) && (s = NUM2INT(size)) < 0) {
-	rb_raise(rb_eArgError, "negative size");
+        rb_raise(rb_eArgError, "negative size");
     }
     if (NIL_P(len) ||
-	(((n = NUM2INT(len)) < 0) ?
-	 (rb_raise(rb_eArgError, "negative length"), 0) :
-	 (b + n * s > l))) {
-	n = (l - b) / s;
+        (((n = NUM2INT(len)) < 0) ?
+         (rb_raise(rb_eArgError, "negative length"), 0) :
+         (b + n * s > l))) {
+        n = (l - b) / s;
     }
     rb_str_modify(str);
     d.enc = rb_enc_get(str);
     d.elsize = s;
     ruby_qsort(RSTRING_PTR(str) + b, n, s,
-	       rb_block_given_p() ? cmp_1 : cmp_2, &d);
+               rb_block_given_p() ? cmp_1 : cmp_2, &d);
     return str;
 }
 
diff --git a/ext/-test-/string/set_len.c b/ext/-test-/string/set_len.c
index 219cea404c..049da2cdb5 100644
--- a/ext/-test-/string/set_len.c
+++ b/ext/-test-/string/set_len.c
@@ -7,8 +7,18 @@ bug_str_set_len(VALUE str, VALUE len)
     return str;
 }
 
+static VALUE
+bug_str_append(VALUE str, VALUE addendum)
+{
+    StringValue(addendum);
+    rb_str_modify_expand(str, RSTRING_LEN(addendum));
+    memcpy(RSTRING_END(str), RSTRING_PTR(addendum), RSTRING_LEN(addendum));
+    return str;
+}
+
 void
 Init_string_set_len(VALUE klass)
 {
     rb_define_method(klass, "set_len", bug_str_set_len, 1);
+    rb_define_method(klass, "append", bug_str_append, 1);
 }
diff --git a/ext/-test-/struct/member.c b/ext/-test-/struct/member.c
index 1d404039b4..f5400fe477 100644
--- a/ext/-test-/struct/member.c
+++ b/ext/-test-/struct/member.c
@@ -6,7 +6,7 @@ bug_struct_get(VALUE obj, VALUE name)
     ID id = rb_check_id(&name);
 
     if (!id) {
-	rb_name_error_str(name, "`%"PRIsVALUE"' is not a struct member", name);
+        rb_name_error_str(name, "`%"PRIsVALUE"' is not a struct member", name);
     }
     return rb_struct_getmember(obj, id);
 }
diff --git a/ext/-test-/symbol/type.c b/ext/-test-/symbol/type.c
index e51e09eb26..8d0e647340 100644
--- a/ext/-test-/symbol/type.c
+++ b/ext/-test-/symbol/type.c
@@ -2,12 +2,12 @@
 
 #ifdef HAVE_RB_IS_CONST_NAME
 # define get_symbol_type(type, t, name) do { \
-	ID id = rb_check_id(&name); \
-	t = (id ? rb_is_##type##_id(id) : rb_is_##type##_name(name)); \
+        ID id = rb_check_id(&name); \
+        t = (id ? rb_is_##type##_id(id) : rb_is_##type##_name(name)); \
     } while (0)
 #else
 # define get_symbol_type(type, t, name) do { \
-	t = rb_is_##type##_id(rb_to_id(name)); \
+        t = rb_is_##type##_id(rb_to_id(name)); \
     } while (0)
 #endif
 
diff --git a/ext/-test-/thread/instrumentation/depend b/ext/-test-/thread/instrumentation/depend
new file mode 100644
index 0000000000..e2fcd060d8
--- /dev/null
+++ b/ext/-test-/thread/instrumentation/depend
@@ -0,0 +1,164 @@
+# AUTOGENERATED DEPENDENCIES START
+instrumentation.o: $(RUBY_EXTCONF_H)
+instrumentation.o: $(arch_hdrdir)/ruby/config.h
+instrumentation.o: $(hdrdir)/ruby/assert.h
+instrumentation.o: $(hdrdir)/ruby/atomic.h
+instrumentation.o: $(hdrdir)/ruby/backward.h
+instrumentation.o: $(hdrdir)/ruby/backward/2/assume.h
+instrumentation.o: $(hdrdir)/ruby/backward/2/attributes.h
+instrumentation.o: $(hdrdir)/ruby/backward/2/bool.h
+instrumentation.o: $(hdrdir)/ruby/backward/2/inttypes.h
+instrumentation.o: $(hdrdir)/ruby/backward/2/limits.h
+instrumentation.o: $(hdrdir)/ruby/backward/2/long_long.h
+instrumentation.o: $(hdrdir)/ruby/backward/2/stdalign.h
+instrumentation.o: $(hdrdir)/ruby/backward/2/stdarg.h
+instrumentation.o: $(hdrdir)/ruby/defines.h
+instrumentation.o: $(hdrdir)/ruby/intern.h
+instrumentation.o: $(hdrdir)/ruby/internal/abi.h
+instrumentation.o: $(hdrdir)/ruby/internal/anyargs.h
+instrumentation.o: $(hdrdir)/ruby/internal/arithmetic.h
+instrumentation.o: $(hdrdir)/ruby/internal/arithmetic/char.h
+instrumentation.o: $(hdrdir)/ruby/internal/arithmetic/double.h
+instrumentation.o: $(hdrdir)/ruby/internal/arithmetic/fixnum.h
+instrumentation.o: $(hdrdir)/ruby/internal/arithmetic/gid_t.h
+instrumentation.o: $(hdrdir)/ruby/internal/arithmetic/int.h
+instrumentation.o: $(hdrdir)/ruby/internal/arithmetic/intptr_t.h
+instrumentation.o: $(hdrdir)/ruby/internal/arithmetic/long.h
+instrumentation.o: $(hdrdir)/ruby/internal/arithmetic/long_long.h
+instrumentation.o: $(hdrdir)/ruby/internal/arithmetic/mode_t.h
+instrumentation.o: $(hdrdir)/ruby/internal/arithmetic/off_t.h
+instrumentation.o: $(hdrdir)/ruby/internal/arithmetic/pid_t.h
+instrumentation.o: $(hdrdir)/ruby/internal/arithmetic/short.h
+instrumentation.o: $(hdrdir)/ruby/internal/arithmetic/size_t.h
+instrumentation.o: $(hdrdir)/ruby/internal/arithmetic/st_data_t.h
+instrumentation.o: $(hdrdir)/ruby/internal/arithmetic/uid_t.h
+instrumentation.o: $(hdrdir)/ruby/internal/assume.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/alloc_size.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/artificial.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/cold.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/const.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/constexpr.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/deprecated.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/diagnose_if.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/enum_extensibility.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/error.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/flag_enum.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/forceinline.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/format.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/maybe_unused.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/noalias.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/nodiscard.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/noexcept.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/noinline.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/nonnull.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/noreturn.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/pure.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/restrict.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/returns_nonnull.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/warning.h
+instrumentation.o: $(hdrdir)/ruby/internal/attr/weakref.h
+instrumentation.o: $(hdrdir)/ruby/internal/cast.h
+instrumentation.o: $(hdrdir)/ruby/internal/compiler_is.h
+instrumentation.o: $(hdrdir)/ruby/internal/compiler_is/apple.h
+instrumentation.o: $(hdrdir)/ruby/internal/compiler_is/clang.h
+instrumentation.o: $(hdrdir)/ruby/internal/compiler_is/gcc.h
+instrumentation.o: $(hdrdir)/ruby/internal/compiler_is/intel.h
+instrumentation.o: $(hdrdir)/ruby/internal/compiler_is/msvc.h
+instrumentation.o: $(hdrdir)/ruby/internal/compiler_is/sunpro.h
+instrumentation.o: $(hdrdir)/ruby/internal/compiler_since.h
+instrumentation.o: $(hdrdir)/ruby/internal/config.h
+instrumentation.o: $(hdrdir)/ruby/internal/constant_p.h
+instrumentation.o: $(hdrdir)/ruby/internal/core.h
+instrumentation.o: $(hdrdir)/ruby/internal/core/rarray.h
+instrumentation.o: $(hdrdir)/ruby/internal/core/rbasic.h
+instrumentation.o: $(hdrdir)/ruby/internal/core/rbignum.h
+instrumentation.o: $(hdrdir)/ruby/internal/core/rclass.h
+instrumentation.o: $(hdrdir)/ruby/internal/core/rdata.h
+instrumentation.o: $(hdrdir)/ruby/internal/core/rfile.h
+instrumentation.o: $(hdrdir)/ruby/internal/core/rhash.h
+instrumentation.o: $(hdrdir)/ruby/internal/core/robject.h
+instrumentation.o: $(hdrdir)/ruby/internal/core/rregexp.h
+instrumentation.o: $(hdrdir)/ruby/internal/core/rstring.h
+instrumentation.o: $(hdrdir)/ruby/internal/core/rstruct.h
+instrumentation.o: $(hdrdir)/ruby/internal/core/rtypeddata.h
+instrumentation.o: $(hdrdir)/ruby/internal/ctype.h
+instrumentation.o: $(hdrdir)/ruby/internal/dllexport.h
+instrumentation.o: $(hdrdir)/ruby/internal/dosish.h
+instrumentation.o: $(hdrdir)/ruby/internal/error.h
+instrumentation.o: $(hdrdir)/ruby/internal/eval.h
+instrumentation.o: $(hdrdir)/ruby/internal/event.h
+instrumentation.o: $(hdrdir)/ruby/internal/fl_type.h
+instrumentation.o: $(hdrdir)/ruby/internal/gc.h
+instrumentation.o: $(hdrdir)/ruby/internal/glob.h
+instrumentation.o: $(hdrdir)/ruby/internal/globals.h
+instrumentation.o: $(hdrdir)/ruby/internal/has/attribute.h
+instrumentation.o: $(hdrdir)/ruby/internal/has/builtin.h
+instrumentation.o: $(hdrdir)/ruby/internal/has/c_attribute.h
+instrumentation.o: $(hdrdir)/ruby/internal/has/cpp_attribute.h
+instrumentation.o: $(hdrdir)/ruby/internal/has/declspec_attribute.h
+instrumentation.o: $(hdrdir)/ruby/internal/has/extension.h
+instrumentation.o: $(hdrdir)/ruby/internal/has/feature.h
+instrumentation.o: $(hdrdir)/ruby/internal/has/warning.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/array.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/bignum.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/class.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/compar.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/complex.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/cont.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/dir.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/enum.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/enumerator.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/error.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/eval.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/file.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/gc.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/hash.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/io.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/load.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/marshal.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/numeric.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/object.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/parse.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/proc.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/process.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/random.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/range.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/rational.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/re.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/ruby.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/select.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/select/largesize.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/signal.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/sprintf.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/string.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/struct.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/thread.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/time.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/variable.h
+instrumentation.o: $(hdrdir)/ruby/internal/intern/vm.h
+instrumentation.o: $(hdrdir)/ruby/internal/interpreter.h
+instrumentation.o: $(hdrdir)/ruby/internal/iterator.h
+instrumentation.o: $(hdrdir)/ruby/internal/memory.h
+instrumentation.o: $(hdrdir)/ruby/internal/method.h
+instrumentation.o: $(hdrdir)/ruby/internal/module.h
+instrumentation.o: $(hdrdir)/ruby/internal/newobj.h
+instrumentation.o: $(hdrdir)/ruby/internal/rgengc.h
+instrumentation.o: $(hdrdir)/ruby/internal/scan_args.h
+instrumentation.o: $(hdrdir)/ruby/internal/special_consts.h
+instrumentation.o: $(hdrdir)/ruby/internal/static_assert.h
+instrumentation.o: $(hdrdir)/ruby/internal/stdalign.h
+instrumentation.o: $(hdrdir)/ruby/internal/stdbool.h
+instrumentation.o: $(hdrdir)/ruby/internal/symbol.h
+instrumentation.o: $(hdrdir)/ruby/internal/value.h
+instrumentation.o: $(hdrdir)/ruby/internal/value_type.h
+instrumentation.o: $(hdrdir)/ruby/internal/variable.h
+instrumentation.o: $(hdrdir)/ruby/internal/warning_push.h
+instrumentation.o: $(hdrdir)/ruby/internal/xmalloc.h
+instrumentation.o: $(hdrdir)/ruby/missing.h
+instrumentation.o: $(hdrdir)/ruby/ruby.h
+instrumentation.o: $(hdrdir)/ruby/st.h
+instrumentation.o: $(hdrdir)/ruby/subst.h
+instrumentation.o: $(hdrdir)/ruby/thread.h
+instrumentation.o: $(hdrdir)/ruby/thread_native.h
+instrumentation.o: instrumentation.c
+# AUTOGENERATED DEPENDENCIES END
diff --git a/ext/-test-/thread/instrumentation/extconf.rb b/ext/-test-/thread/instrumentation/extconf.rb
new file mode 100644
index 0000000000..a48ba3c045
--- /dev/null
+++ b/ext/-test-/thread/instrumentation/extconf.rb
@@ -0,0 +1,2 @@
+# frozen_string_literal: false
+create_makefile("-test-/thread/instrumentation")
diff --git a/ext/-test-/thread/instrumentation/instrumentation.c b/ext/-test-/thread/instrumentation/instrumentation.c
new file mode 100644
index 0000000000..d2a2c2740b
--- /dev/null
+++ b/ext/-test-/thread/instrumentation/instrumentation.c
@@ -0,0 +1,141 @@
+#include "ruby/ruby.h"
+#include "ruby/atomic.h"
+#include "ruby/thread.h"
+
+static rb_atomic_t started_count = 0;
+static rb_atomic_t ready_count = 0;
+static rb_atomic_t resumed_count = 0;
+static rb_atomic_t suspended_count = 0;
+static rb_atomic_t exited_count = 0;
+
+#if __STDC_VERSION__ >= 201112
+  #define RB_THREAD_LOCAL_SPECIFIER _Thread_local
+#elif defined(__GNUC__) && !defined(RB_THREAD_LOCAL_SPECIFIER_IS_UNSUPPORTED)
+  /* note that ICC (linux) and Clang are covered by __GNUC__ */
+  #define RB_THREAD_LOCAL_SPECIFIER __thread
+#else
+  #define RB_THREAD_LOCAL_SPECIFIER
+#endif
+
+static RB_THREAD_LOCAL_SPECIFIER unsigned int local_ready_count = 0;
+static RB_THREAD_LOCAL_SPECIFIER unsigned int local_resumed_count = 0;
+static RB_THREAD_LOCAL_SPECIFIER unsigned int local_suspended_count = 0;
+
+static void
+ex_callback(rb_event_flag_t event, const rb_internal_thread_event_data_t *event_data, void *user_data)
+{
+    switch (event) {
+      case RUBY_INTERNAL_THREAD_EVENT_STARTED:
+        RUBY_ATOMIC_INC(started_count);
+        break;
+      case RUBY_INTERNAL_THREAD_EVENT_READY:
+        RUBY_ATOMIC_INC(ready_count);
+        local_ready_count++;
+        break;
+      case RUBY_INTERNAL_THREAD_EVENT_RESUMED:
+        RUBY_ATOMIC_INC(resumed_count);
+        local_resumed_count++;
+        break;
+      case RUBY_INTERNAL_THREAD_EVENT_SUSPENDED:
+        RUBY_ATOMIC_INC(suspended_count);
+        local_suspended_count++;
+        break;
+      case RUBY_INTERNAL_THREAD_EVENT_EXITED:
+        RUBY_ATOMIC_INC(exited_count);
+        break;
+    }
+}
+
+static rb_internal_thread_event_hook_t * single_hook = NULL;
+
+static VALUE
+thread_counters(VALUE thread)
+{
+    VALUE array = rb_ary_new2(5);
+    rb_ary_push(array, UINT2NUM(started_count));
+    rb_ary_push(array, UINT2NUM(ready_count));
+    rb_ary_push(array, UINT2NUM(resumed_count));
+    rb_ary_push(array, UINT2NUM(suspended_count));
+    rb_ary_push(array, UINT2NUM(exited_count));
+    return array;
+}
+
+static VALUE
+thread_local_counters(VALUE thread)
+{
+    VALUE array = rb_ary_new2(3);
+    rb_ary_push(array, UINT2NUM(local_ready_count));
+    rb_ary_push(array, UINT2NUM(local_resumed_count));
+    rb_ary_push(array, UINT2NUM(local_suspended_count));
+    return array;
+}
+
+static VALUE
+thread_reset_counters(VALUE thread)
+{
+    RUBY_ATOMIC_SET(started_count, 0);
+    RUBY_ATOMIC_SET(ready_count, 0);
+    RUBY_ATOMIC_SET(resumed_count, 0);
+    RUBY_ATOMIC_SET(suspended_count, 0);
+    RUBY_ATOMIC_SET(exited_count, 0);
+    local_ready_count = 0;
+    local_resumed_count = 0;
+    local_suspended_count = 0;
+    return Qtrue;
+}
+
+static VALUE
+thread_register_callback(VALUE thread)
+{
+    single_hook = rb_internal_thread_add_event_hook(
+        ex_callback,
+        RUBY_INTERNAL_THREAD_EVENT_STARTED |
+        RUBY_INTERNAL_THREAD_EVENT_READY |
+        RUBY_INTERNAL_THREAD_EVENT_RESUMED |
+        RUBY_INTERNAL_THREAD_EVENT_SUSPENDED |
+        RUBY_INTERNAL_THREAD_EVENT_EXITED,
+        NULL
+    );
+
+    return Qnil;
+}
+
+static VALUE
+thread_unregister_callback(VALUE thread)
+{
+    if (single_hook) {
+        rb_internal_thread_remove_event_hook(single_hook);
+        single_hook = NULL;
+    }
+
+    return Qnil;
+}
+
+static VALUE
+thread_register_and_unregister_callback(VALUE thread)
+{
+    rb_internal_thread_event_hook_t * hooks[5];
+    for (int i = 0; i < 5; i++) {
+        hooks[i] = rb_internal_thread_add_event_hook(ex_callback, RUBY_INTERNAL_THREAD_EVENT_READY, NULL);
+    }
+
+    if (!rb_internal_thread_remove_event_hook(hooks[4])) return Qfalse;
+    if (!rb_internal_thread_remove_event_hook(hooks[0])) return Qfalse;
+    if (!rb_internal_thread_remove_event_hook(hooks[3])) return Qfalse;
+    if (!rb_internal_thread_remove_event_hook(hooks[2])) return Qfalse;
+    if (!rb_internal_thread_remove_event_hook(hooks[1])) return Qfalse;
+    return Qtrue;
+}
+
+void
+Init_instrumentation(void)
+{
+    VALUE mBug = rb_define_module("Bug");
+    VALUE klass = rb_define_module_under(mBug, "ThreadInstrumentation");
+    rb_define_singleton_method(klass, "counters", thread_counters, 0);
+    rb_define_singleton_method(klass, "local_counters", thread_local_counters, 0);
+    rb_define_singleton_method(klass, "reset_counters", thread_reset_counters, 0);
+    rb_define_singleton_method(klass, "register_callback", thread_register_callback, 0);
+    rb_define_singleton_method(klass, "unregister_callback", thread_unregister_callback, 0);
+    rb_define_singleton_method(klass, "register_and_unregister_callbacks", thread_register_and_unregister_callback, 0);
+}
diff --git a/ext/-test-/tracepoint/gc_hook.c b/ext/-test-/tracepoint/gc_hook.c
index 5fd46fa518..a3f4e7f68a 100644
--- a/ext/-test-/tracepoint/gc_hook.c
+++ b/ext/-test-/tracepoint/gc_hook.c
@@ -28,12 +28,12 @@ static void
 gc_start_end_i(VALUE tpval, void *data)
 {
     if (0) {
-	rb_trace_arg_t *tparg = rb_tracearg_from_tracepoint(tpval);
-	fprintf(stderr, "trace: %s\n", rb_tracearg_event_flag(tparg) == RUBY_INTERNAL_EVENT_GC_START ? "gc_start" : "gc_end");
+        rb_trace_arg_t *tparg = rb_tracearg_from_tracepoint(tpval);
+        fprintf(stderr, "trace: %s\n", rb_tracearg_event_flag(tparg) == RUBY_INTERNAL_EVENT_GC_START ? "gc_start" : "gc_end");
     }
 
     if (invoking == 0) {
-	rb_postponed_job_register(0, invoke_proc, data);
+        rb_postponed_job_register(0, invoke_proc, data);
     }
 }
 
@@ -45,19 +45,19 @@ set_gc_hook(VALUE module, VALUE proc, rb_event_flag_t event, const char *tp_str,
 
     /* disable previous keys */
     if (rb_ivar_defined(module, tp_key) != 0 &&
-	RTEST(tpval = rb_ivar_get(module, tp_key))) {
-	rb_tracepoint_disable(tpval);
-	rb_ivar_set(module, tp_key, Qnil);
+        RTEST(tpval = rb_ivar_get(module, tp_key))) {
+        rb_tracepoint_disable(tpval);
+        rb_ivar_set(module, tp_key, Qnil);
     }
 
     if (RTEST(proc)) {
-	if (!rb_obj_is_proc(proc)) {
-	    rb_raise(rb_eTypeError, "trace_func needs to be Proc");
-	}
+        if (!rb_obj_is_proc(proc)) {
+            rb_raise(rb_eTypeError, "trace_func needs to be Proc");
+        }
 
-	tpval = rb_tracepoint_new(0, event, gc_start_end_i, (void *)proc);
-	rb_ivar_set(module, tp_key, tpval);
-	rb_tracepoint_enable(tpval);
+        tpval = rb_tracepoint_new(0, event, gc_start_end_i, (void *)proc);
+        rb_ivar_set(module, tp_key, tpval);
+        rb_tracepoint_enable(tpval);
     }
 
     return proc;
@@ -67,7 +67,7 @@ static VALUE
 set_after_gc_start(VALUE module, VALUE proc)
 {
     return set_gc_hook(module, proc, RUBY_INTERNAL_EVENT_GC_START,
-		       "__set_after_gc_start_tpval__", "__set_after_gc_start_proc__");
+                       "__set_after_gc_start_tpval__", "__set_after_gc_start_proc__");
 }
 
 static VALUE
diff --git a/ext/-test-/tracepoint/tracepoint.c b/ext/-test-/tracepoint/tracepoint.c
index aa8c212f99..2826cc038c 100644
--- a/ext/-test-/tracepoint/tracepoint.c
+++ b/ext/-test-/tracepoint/tracepoint.c
@@ -21,35 +21,35 @@ tracepoint_track_objspace_events_i(VALUE tpval, void *data)
 
     switch (rb_tracearg_event_flag(tparg)) {
       case RUBY_INTERNAL_EVENT_NEWOBJ:
-	{
-	    VALUE obj = rb_tracearg_object(tparg);
-	    if (track->objects_count < objects_max)
-		track->objects[track->objects_count++] = obj;
-	    track->newobj_count++;
-	    break;
-	}
+        {
+            VALUE obj = rb_tracearg_object(tparg);
+            if (track->objects_count < objects_max)
+                track->objects[track->objects_count++] = obj;
+            track->newobj_count++;
+            break;
+        }
       case RUBY_INTERNAL_EVENT_FREEOBJ:
-	{
-	    track->free_count++;
-	    break;
-	}
+        {
+            track->free_count++;
+            break;
+        }
       case RUBY_INTERNAL_EVENT_GC_START:
-	{
-	    track->gc_start_count++;
-	    break;
-	}
+        {
+            track->gc_start_count++;
+            break;
+        }
       case RUBY_INTERNAL_EVENT_GC_END_MARK:
-	{
-	    track->gc_end_mark_count++;
-	    break;
-	}
+        {
+            track->gc_end_mark_count++;
+            break;
+        }
       case RUBY_INTERNAL_EVENT_GC_END_SWEEP:
-	{
-	    track->gc_end_sweep_count++;
-	    break;
-	}
+        {
+            track->gc_end_sweep_count++;
+            break;
+        }
       default:
-	rb_raise(rb_eRuntimeError, "unknown event");
+        rb_raise(rb_eRuntimeError, "unknown event");
     }
 }
 
@@ -58,9 +58,9 @@ tracepoint_track_objspace_events(VALUE self)
 {
     struct tracepoint_track track = {0, 0, 0, 0, 0,};
     VALUE tpval = rb_tracepoint_new(0, RUBY_INTERNAL_EVENT_NEWOBJ | RUBY_INTERNAL_EVENT_FREEOBJ |
-				    RUBY_INTERNAL_EVENT_GC_START | RUBY_INTERNAL_EVENT_GC_END_MARK |
-				    RUBY_INTERNAL_EVENT_GC_END_SWEEP,
-				    tracepoint_track_objspace_events_i, &track);
+                                    RUBY_INTERNAL_EVENT_GC_START | RUBY_INTERNAL_EVENT_GC_END_MARK |
+                                    RUBY_INTERNAL_EVENT_GC_END_SWEEP,
+                                    tracepoint_track_objspace_events_i, &track);
     VALUE result = rb_ary_new();
 
     rb_tracepoint_enable(tpval);
diff --git a/ext/-test-/typeddata/typeddata.c b/ext/-test-/typeddata/typeddata.c
index 2adfd56ae8..cf3178fd18 100644
--- a/ext/-test-/typeddata/typeddata.c
+++ b/ext/-test-/typeddata/typeddata.c
@@ -27,7 +27,7 @@ test_make(VALUE klass, VALUE num)
     unsigned long i, n = NUM2UINT(num);
 
     for (i = 0; i < n; i++) {
-	test_alloc(klass);
+        test_alloc(klass);
     }
 
     return Qnil;
diff --git a/ext/-test-/vm/at_exit.c b/ext/-test-/vm/at_exit.c
index 6cfbfafa9e..efc439b26a 100644
--- a/ext/-test-/vm/at_exit.c
+++ b/ext/-test-/vm/at_exit.c
@@ -23,14 +23,14 @@ register_at_exit(VALUE self, VALUE t)
 {
     switch (t) {
       case Qtrue:
-	ruby_vm_at_exit(print_begin);
-	break;
+        ruby_vm_at_exit(print_begin);
+        break;
       case Qfalse:
-	ruby_vm_at_exit(print_end);
-	break;
+        ruby_vm_at_exit(print_end);
+        break;
       default:
-	ruby_vm_at_exit(do_nothing);
-	break;
+        ruby_vm_at_exit(do_nothing);
+        break;
     }
     return self;
 }
diff --git a/ext/-test-/win32/console/attribute.c b/ext/-test-/win32/console/attribute.c
index e3e80a199f..b43ba23a5c 100644
--- a/ext/-test-/win32/console/attribute.c
+++ b/ext/-test-/win32/console/attribute.c
@@ -19,13 +19,13 @@ console_info(VALUE klass, VALUE io)
     CONSOLE_SCREEN_BUFFER_INFO csbi;
 
     if (!GetConsoleScreenBufferInfo(h, &csbi))
-	rb_syserr_fail(rb_w32_map_errno(GetLastError()), "not console");
+        rb_syserr_fail(rb_w32_map_errno(GetLastError()), "not console");
     return rb_struct_new(rb_cConsoleScreenBufferInfo,
-			 INT2FIX(csbi.dwSize.X),
-			 INT2FIX(csbi.dwSize.Y),
-			 INT2FIX(csbi.dwCursorPosition.X),
-			 INT2FIX(csbi.dwCursorPosition.Y),
-			 INT2FIX(csbi.wAttributes));
+                         INT2FIX(csbi.dwSize.X),
+                         INT2FIX(csbi.dwSize.Y),
+                         INT2FIX(csbi.dwCursorPosition.X),
+                         INT2FIX(csbi.dwCursorPosition.Y),
+                         INT2FIX(csbi.wAttributes));
 }
 
 static VALUE
@@ -44,9 +44,9 @@ void
 Init_attribute(VALUE m)
 {
     rb_cConsoleScreenBufferInfo = rb_struct_define_under(m, "ConsoleScreenBufferInfo",
-							 "size_x", "size_y",
-							 "cur_x", "cur_y",
-							 "attr", NULL);
+                                                         "size_x", "size_y",
+                                                         "cur_x", "cur_y",
+                                                         "attr", NULL);
     rb_define_singleton_method(m, "console_info", console_info, 1);
     rb_define_singleton_method(m, "console_attribute", console_set_attribute, 2);
 
diff --git a/ext/-test-/win32/fd_setsize/fd_setsize.c b/ext/-test-/win32/fd_setsize/fd_setsize.c
index 8da8b1eaa0..e29114a0ca 100644
--- a/ext/-test-/win32/fd_setsize/fd_setsize.c
+++ b/ext/-test-/win32/fd_setsize/fd_setsize.c
@@ -37,11 +37,11 @@ test_fdset(VALUE self)
     FD_ZERO(&set);
 
     for (i = 0; i < FD_SETSIZE * 2; i++) {
-	int sd = socket(AF_INET, SOCK_DGRAM, 0);
-	FD_SET(sd, &set);
-	if (set.fd_count > FD_SETSIZE) {
-	    return Qfalse;
-	}
+        int sd = socket(AF_INET, SOCK_DGRAM, 0);
+        FD_SET(sd, &set);
+        if (set.fd_count > FD_SETSIZE) {
+            return Qfalse;
+        }
     }
     return Qtrue;
 }
diff --git a/ext/bigdecimal/bigdecimal.c b/ext/bigdecimal/bigdecimal.c
index fc74c0be53..d6ea35c615 100644
--- a/ext/bigdecimal/bigdecimal.c
+++ b/ext/bigdecimal/bigdecimal.c
@@ -7,9 +7,7 @@
  */
 
 /* #define BIGDECIMAL_DEBUG 1 */
-#ifdef BIGDECIMAL_DEBUG
-# define BIGDECIMAL_ENABLE_VPRINT 1
-#endif
+
 #include "bigdecimal.h"
 #include "ruby/util.h"
 
@@ -61,6 +59,13 @@ static ID id_to_r;
 static ID id_eq;
 static ID id_half;
 
+#define RBD_NUM_ROUNDING_MODES 11
+
+static struct {
+    ID id;
+    uint8_t mode;
+} rbd_rounding_modes[RBD_NUM_ROUNDING_MODES];
+
 /* MACRO's to guard objects from GC by keeping them in stack */
 #ifdef RBIMPL_ATTR_MAYBE_UNUSED
 #define ENTER(n) RBIMPL_ATTR_MAYBE_UNUSED() volatile VALUE vStack[n];int iStack=0
@@ -102,10 +107,164 @@ static ID id_half;
 # define RB_OBJ_STRING(obj) StringValueCStr(obj)
 #endif
 
+#ifndef MAYBE_UNUSED
+# define MAYBE_UNUSED(x) x
+#endif
+
 #define BIGDECIMAL_POSITIVE_P(bd) ((bd)->sign > 0)
 #define BIGDECIMAL_NEGATIVE_P(bd) ((bd)->sign < 0)
 
 /*
+ * ================== Memory allocation ============================
+ */
+
+#ifdef BIGDECIMAL_DEBUG
+static size_t rbd_allocation_count = 0;   /* Memory allocation counter */
+static inline void
+atomic_allocation_count_inc(void)
+{
+    RUBY_ATOMIC_SIZE_INC(rbd_allocation_count);
+}
+static inline void
+atomic_allocation_count_dec_nounderflow(void)
+{
+    if (rbd_allocation_count == 0) return;
+    RUBY_ATOMIC_SIZE_DEC(rbd_allocation_count);
+}
+static void
+check_allocation_count_nonzero(void)
+{
+    if (rbd_allocation_count != 0) return;
+    rb_bug("[bigdecimal][rbd_free_struct] Too many memory free calls");
+}
+#else
+#   define atomic_allocation_count_inc() /* nothing */
+#   define atomic_allocation_count_dec_nounderflow() /* nothing */
+#   define check_allocation_count_nonzero() /* nothing */
+#endif /* BIGDECIMAL_DEBUG */
+
+PUREFUNC(static inline size_t rbd_struct_size(size_t const));
+
+static inline size_t
+rbd_struct_size(size_t const internal_digits)
+{
+    size_t const frac_len = (internal_digits == 0) ? 1 : internal_digits;
+    return offsetof(Real, frac) + frac_len * sizeof(DECDIG);
+}
+
+static inline Real *
+rbd_allocate_struct(size_t const internal_digits)
+{
+    size_t const size = rbd_struct_size(internal_digits);
+    Real *real = ruby_xcalloc(1, size);
+    atomic_allocation_count_inc();
+    real->MaxPrec = internal_digits;
+    return real;
+}
+
+static size_t
+rbd_calculate_internal_digits(size_t const digits, bool limit_precision)
+{
+    size_t const len = roomof(digits, BASE_FIG);
+    if (limit_precision) {
+        size_t const prec_limit = VpGetPrecLimit();
+        if (prec_limit > 0) {
+            /* NOTE: 2 more digits for rounding and division */
+            size_t const max_len = roomof(prec_limit, BASE_FIG) + 2;
+            if (len > max_len)
+                return max_len;
+        }
+    }
+
+    return len;
+}
+
+static inline Real *
+rbd_allocate_struct_decimal_digits(size_t const decimal_digits, bool limit_precision)
+{
+    size_t const internal_digits = rbd_calculate_internal_digits(decimal_digits, limit_precision);
+    return rbd_allocate_struct(internal_digits);
+}
+
+static VALUE BigDecimal_wrap_struct(VALUE obj, Real *vp);
+
+static Real *
+rbd_reallocate_struct(Real *real, size_t const internal_digits)
+{
+    size_t const size = rbd_struct_size(internal_digits);
+    VALUE obj = real ? real->obj : 0;
+    Real *new_real = (Real *)ruby_xrealloc(real, size);
+    new_real->MaxPrec = internal_digits;
+    if (obj) {
+        new_real->obj = 0;
+        BigDecimal_wrap_struct(obj, new_real);
+    }
+    return new_real;
+}
+
+static void
+rbd_free_struct(Real *real)
+{
+    if (real != NULL) {
+        check_allocation_count_nonzero();
+        ruby_xfree(real);
+        atomic_allocation_count_dec_nounderflow();
+    }
+}
+
+#define NewZero rbd_allocate_struct_zero
+static Real *
+rbd_allocate_struct_zero(int sign, size_t const digits, bool limit_precision)
+{
+    Real *real = rbd_allocate_struct_decimal_digits(digits, limit_precision);
+    VpSetZero(real, sign);
+    return real;
+}
+
+MAYBE_UNUSED(static inline Real * rbd_allocate_struct_zero_limited(int sign, size_t const digits));
+#define NewZeroLimited rbd_allocate_struct_zero_limited
+static inline Real *
+rbd_allocate_struct_zero_limited(int sign, size_t const digits)
+{
+    return rbd_allocate_struct_zero(sign, digits, true);
+}
+
+MAYBE_UNUSED(static inline Real * rbd_allocate_struct_zero_nolimit(int sign, size_t const digits));
+#define NewZeroNolimit rbd_allocate_struct_zero_nolimit
+static inline Real *
+rbd_allocate_struct_zero_nolimit(int sign, size_t const digits)
+{
+    return rbd_allocate_struct_zero(sign, digits, false);
+}
+
+#define NewOne rbd_allocate_struct_one
+static Real *
+rbd_allocate_struct_one(int sign, size_t const digits, bool limit_precision)
+{
+    Real *real = rbd_allocate_struct_decimal_digits(digits, limit_precision);
+    VpSetOne(real);
+    if (sign < 0)
+        VpSetSign(real, VP_SIGN_NEGATIVE_FINITE);
+    return real;
+}
+
+MAYBE_UNUSED(static inline Real * rbd_allocate_struct_one_limited(int sign, size_t const digits));
+#define NewOneLimited rbd_allocate_struct_one_limited
+static inline Real *
+rbd_allocate_struct_one_limited(int sign, size_t const digits)
+{
+    return rbd_allocate_struct_one(sign, digits, true);
+}
+
+MAYBE_UNUSED(static inline Real * rbd_allocate_struct_one_nolimit(int sign, size_t const digits));
+#define NewOneNolimit rbd_allocate_struct_one_nolimit
+static inline Real *
+rbd_allocate_struct_one_nolimit(int sign, size_t const digits)
+{
+    return rbd_allocate_struct_one(sign, digits, false);
+}
+
+/*
  * ================== Ruby Interface part ==========================
  */
 #define DoSomeOne(x,y,f) rb_num_coerce_bin(x,y,f)
@@ -120,10 +279,7 @@ static VALUE VpCheckGetValue(Real *p);
 static void  VpInternalRound(Real *c, size_t ixDigit, DECDIG vPrev, DECDIG v);
 static int   VpLimitRound(Real *c, size_t ixDigit);
 static Real *VpCopy(Real *pv, Real const* const x);
-
-#ifdef BIGDECIMAL_ENABLE_VPRINT
 static int VPrint(FILE *fp,const char *cntl_chr,Real *a);
-#endif
 
 /*
  *  **** BigDecimal part ****
@@ -138,7 +294,7 @@ static VALUE BigDecimal_negative_zero(void);
 static void
 BigDecimal_delete(void *pv)
 {
-    VpFree(pv);
+    rbd_free_struct(pv);
 }
 
 static size_t
@@ -161,6 +317,60 @@ static const rb_data_type_t BigDecimal_data_type = {
 #endif
 };
 
+static Real *
+rbd_allocate_struct_zero_wrap_klass(VALUE klass, int sign, size_t const digits, bool limit_precision)
+{
+    Real *real = rbd_allocate_struct_zero(sign, digits, limit_precision);
+    if (real != NULL) {
+        VALUE obj = TypedData_Wrap_Struct(klass, &BigDecimal_data_type, 0);
+        BigDecimal_wrap_struct(obj, real);
+    }
+    return real;
+}
+
+MAYBE_UNUSED(static inline Real * rbd_allocate_struct_zero_limited_wrap(int sign, size_t const digits));
+#define NewZeroWrapLimited rbd_allocate_struct_zero_limited_wrap
+static inline Real *
+rbd_allocate_struct_zero_limited_wrap(int sign, size_t const digits)
+{
+    return rbd_allocate_struct_zero_wrap_klass(rb_cBigDecimal, sign, digits, true);
+}
+
+MAYBE_UNUSED(static inline Real * rbd_allocate_struct_zero_nolimit_wrap(int sign, size_t const digits));
+#define NewZeroWrapNolimit rbd_allocate_struct_zero_nolimit_wrap
+static inline Real *
+rbd_allocate_struct_zero_nolimit_wrap(int sign, size_t const digits)
+{
+    return rbd_allocate_struct_zero_wrap_klass(rb_cBigDecimal, sign, digits, false);
+}
+
+static Real *
+rbd_allocate_struct_one_wrap_klass(VALUE klass, int sign, size_t const digits, bool limit_precision)
+{
+    Real *real = rbd_allocate_struct_one(sign, digits, limit_precision);
+    if (real != NULL) {
+        VALUE obj = TypedData_Wrap_Struct(klass, &BigDecimal_data_type, 0);
+        BigDecimal_wrap_struct(obj, real);
+    }
+    return real;
+}
+
+MAYBE_UNUSED(static inline Real * rbd_allocate_struct_one_limited_wrap(int sign, size_t const digits));
+#define NewOneWrapLimited rbd_allocate_struct_one_limited_wrap
+static inline Real *
+rbd_allocate_struct_one_limited_wrap(int sign, size_t const digits)
+{
+    return rbd_allocate_struct_one_wrap_klass(rb_cBigDecimal, sign, digits, true);
+}
+
+MAYBE_UNUSED(static inline Real * rbd_allocate_struct_one_nolimit_wrap(int sign, size_t const digits));
+#define NewOneWrapNolimit rbd_allocate_struct_one_nolimit_wrap
+static inline Real *
+rbd_allocate_struct_one_nolimit_wrap(int sign, size_t const digits)
+{
+    return rbd_allocate_struct_one_wrap_klass(rb_cBigDecimal, sign, digits, false);
+}
+
 static inline int
 is_kind_of_BigDecimal(VALUE const v)
 {
@@ -214,7 +424,7 @@ GetVpValueWithPrec(VALUE v, long prec, int must)
 
       case T_FIXNUM: {
         char szD[128];
-        sprintf(szD, "%ld", FIX2LONG(v));
+        snprintf(szD, 128, "%ld", FIX2LONG(v));
         v = rb_cstr_convert_to_BigDecimal(szD, VpBaseFig() * 2 + 1, must);
         break;
       }
@@ -249,7 +459,7 @@ SomeOneMayDoIt:
     return NULL; /* NULL means to coerce */
 }
 
-static Real*
+static inline Real*
 GetVpValue(VALUE v, int must)
 {
     return GetVpValueWithPrec(v, -1, must);
@@ -264,7 +474,7 @@ GetVpValue(VALUE v, int must)
  *    BigDecimal.double_fig # => 16
  *
  */
-static VALUE
+static inline VALUE
 BigDecimal_double_fig(VALUE self)
 {
     return INT2FIX(VpDblFig());
@@ -486,15 +696,15 @@ BigDecimal_precision_scale(VALUE self)
  *
  *  Returns the number of decimal significant digits in +self+.
  *
- *    BigDecimal("0").scale         # => 0
- *    BigDecimal("1").scale         # => 1
- *    BigDecimal("1.1").scale       # => 2
- *    BigDecimal("3.1415").scale    # => 5
- *    BigDecimal("-1e20").precision # => 1
- *    BigDecimal("1e-20").precision # => 1
- *    BigDecimal("Infinity").scale  # => 0
- *    BigDecimal("-Infinity").scale # => 0
- *    BigDecimal("NaN").scale       # => 0
+ *    BigDecimal("0").n_significant_digits         # => 0
+ *    BigDecimal("1").n_significant_digits         # => 1
+ *    BigDecimal("1.1").n_significant_digits       # => 2
+ *    BigDecimal("3.1415").n_significant_digits    # => 5
+ *    BigDecimal("-1e20").n_significant_digits     # => 1
+ *    BigDecimal("1e-20").n_significant_digits     # => 1
+ *    BigDecimal("Infinity").n_significant_digits  # => 0
+ *    BigDecimal("-Infinity").n_significant_digits # => 0
+ *    BigDecimal("NaN").n_significant_digits       # => 0
  */
 static VALUE
 BigDecimal_n_significant_digits(VALUE self)
@@ -573,13 +783,15 @@ BigDecimal_dump(int argc, VALUE *argv, VALUE self)
     char *psz;
     VALUE dummy;
     volatile VALUE dump;
+    size_t len;
 
     rb_scan_args(argc, argv, "01", &dummy);
     GUARD_OBJ(vp,GetVpValue(self, 1));
     dump = rb_str_new(0, VpNumOfChars(vp, "E")+50);
     psz = RSTRING_PTR(dump);
-    sprintf(psz, "%"PRIuSIZE":", VpMaxPrec(vp)*VpBaseFig());
-    VpToString(vp, psz+strlen(psz), 0, 0);
+    snprintf(psz, RSTRING_LEN(dump), "%"PRIuSIZE":", VpMaxPrec(vp)*VpBaseFig());
+    len = strlen(psz);
+    VpToString(vp, psz+len, RSTRING_LEN(dump)-len, 0, 0);
     rb_str_resize(dump, strlen(psz));
     return dump;
 }
@@ -623,18 +835,19 @@ check_rounding_mode_option(VALUE const opts)
     assert(RB_TYPE_P(opts, T_HASH));
 
     if (NIL_P(opts))
-        goto noopt;
+        goto no_opt;
 
     mode = rb_hash_lookup2(opts, ID2SYM(id_half), Qundef);
     if (mode == Qundef || NIL_P(mode))
-        goto noopt;
+        goto no_opt;
 
     if (SYMBOL_P(mode))
         mode = rb_sym2str(mode);
     else if (!RB_TYPE_P(mode, T_STRING)) {
-	VALUE str_mode = rb_check_string_type(mode);
-	if (NIL_P(str_mode)) goto invalid;
-	mode = str_mode;
+        VALUE str_mode = rb_check_string_type(mode);
+        if (NIL_P(str_mode))
+            goto invalid;
+        mode = str_mode;
     }
     s = RSTRING_PTR(mode);
     l = RSTRING_LEN(mode);
@@ -652,13 +865,11 @@ check_rounding_mode_option(VALUE const opts)
       default:
         break;
     }
+
   invalid:
-    if (NIL_P(mode))
-	rb_raise(rb_eArgError, "invalid rounding mode: nil");
-    else
-	rb_raise(rb_eArgError, "invalid rounding mode: %"PRIsVALUE, mode);
+    rb_raise(rb_eArgError, "invalid rounding mode (%"PRIsVALUE")", mode);
 
-  noopt:
+  no_opt:
     return VpGetRoundMode();
 }
 
@@ -667,34 +878,23 @@ check_rounding_mode(VALUE const v)
 {
     unsigned short sw;
     ID id;
-    switch (TYPE(v)) {
-      case T_SYMBOL:
-	id = SYM2ID(v);
-	if (id == id_up)
-	    return VP_ROUND_UP;
-	if (id == id_down || id == id_truncate)
-	    return VP_ROUND_DOWN;
-	if (id == id_half_up || id == id_default)
-	    return VP_ROUND_HALF_UP;
-	if (id == id_half_down)
-	    return VP_ROUND_HALF_DOWN;
-	if (id == id_half_even || id == id_banker)
-	    return VP_ROUND_HALF_EVEN;
-	if (id == id_ceiling || id == id_ceil)
-	    return VP_ROUND_CEIL;
-	if (id == id_floor)
-	    return VP_ROUND_FLOOR;
-	rb_raise(rb_eArgError, "invalid rounding mode");
-
-      default:
-	break;
+    if (RB_TYPE_P(v, T_SYMBOL)) {
+        int i;
+        id = SYM2ID(v);
+        for (i = 0; i < RBD_NUM_ROUNDING_MODES; ++i) {
+            if (rbd_rounding_modes[i].id == id) {
+                return rbd_rounding_modes[i].mode;
+            }
+        }
+        rb_raise(rb_eArgError, "invalid rounding mode (%"PRIsVALUE")", v);
     }
-
-    sw = NUM2USHORT(v);
-    if (!VpIsRoundMode(sw)) {
-	rb_raise(rb_eArgError, "invalid rounding mode");
+    else {
+        sw = NUM2USHORT(v);
+        if (!VpIsRoundMode(sw)) {
+            rb_raise(rb_eArgError, "invalid rounding mode (%"PRIsVALUE")", v);
+        }
+        return sw;
     }
-    return sw;
 }
 
 /*  call-seq:
@@ -933,11 +1133,17 @@ GetAddSubPrec(Real *a, Real *b)
     return mx;
 }
 
-static SIGNED_VALUE
-GetPrecisionInt(VALUE v)
+static inline SIGNED_VALUE
+check_int_precision(VALUE v)
 {
     SIGNED_VALUE n;
-    n = NUM2INT(v);
+#if SIZEOF_VALUE <= SIZEOF_LONG
+    n = (SIGNED_VALUE)NUM2LONG(v);
+#elif SIZEOF_VALUE <= SIZEOF_LONG_LONG
+    n = (SIGNED_VALUE)NUM2LL(v);
+#else
+#   error SIZEOF_VALUE is too large
+#endif
     if (n < 0) {
 	rb_raise(rb_eArgError, "negative precision");
     }
@@ -979,26 +1185,12 @@ VpCreateRbObject(size_t mx, const char *str, bool raise_exception)
     return VpNewRbClass(mx, str, rb_cBigDecimal, true, raise_exception);
 }
 
-#define VpAllocReal(prec) (Real *)VpMemAlloc(offsetof(Real, frac) + (prec) * sizeof(DECDIG))
-
-static Real *
-VpReallocReal(Real *pv, size_t prec)
-{
-    VALUE obj = pv ? pv->obj : 0;
-    Real *new_pv = (Real *)VpMemRealloc(pv, offsetof(Real, frac) + prec * sizeof(DECDIG));
-    if (obj) {
-        new_pv->obj = 0;
-        BigDecimal_wrap_struct(obj, new_pv);
-    }
-    return new_pv;
-}
-
 static Real *
 VpCopy(Real *pv, Real const* const x)
 {
     assert(x != NULL);
 
-    pv = VpReallocReal(pv, x->MaxPrec);
+    pv = rbd_reallocate_struct(pv, x->MaxPrec);
     pv->MaxPrec = x->MaxPrec;
     pv->Prec = x->Prec;
     pv->exponent = x->exponent;
@@ -1119,7 +1311,7 @@ BigDecimal_to_f(VALUE self)
 
     str = rb_str_new(0, VpNumOfChars(p, "E"));
     buf = RSTRING_PTR(str);
-    VpToString(p, buf, 0, 0);
+    VpToString(p, buf, RSTRING_LEN(str), 0, 0);
     errno = 0;
     d = strtod(buf, 0);
     if (errno == ERANGE) {
@@ -1276,17 +1468,17 @@ BigDecimal_add(VALUE self, VALUE r)
 
     mx = GetAddSubPrec(a, b);
     if (mx == (size_t)-1L) {
-        GUARD_OBJ(c, VpCreateRbObject(VpBaseFig() + 1, "0", true));
-	VpAddSub(c, a, b, 1);
+        GUARD_OBJ(c, NewZeroWrapLimited(1, VpBaseFig() + 1));
+        VpAddSub(c, a, b, 1);
     }
     else {
-        GUARD_OBJ(c, VpCreateRbObject(mx * (VpBaseFig() + 1), "0", true));
-	if(!mx) {
-	    VpSetInf(c, VpGetSign(a));
-	}
-	else {
-	    VpAddSub(c, a, b, 1);
-	}
+        GUARD_OBJ(c, NewZeroWrapLimited(1, mx * (VpBaseFig() + 1)));
+        if (!mx) {
+            VpSetInf(c, VpGetSign(a));
+        }
+        else {
+            VpAddSub(c, a, b, 1);
+        }
     }
     return VpCheckGetValue(c);
 }
@@ -1331,17 +1523,17 @@ BigDecimal_sub(VALUE self, VALUE r)
 
     mx = GetAddSubPrec(a,b);
     if (mx == (size_t)-1L) {
-        GUARD_OBJ(c, VpCreateRbObject(VpBaseFig() + 1, "0", true));
-	VpAddSub(c, a, b, -1);
+        GUARD_OBJ(c, NewZeroWrapLimited(1, VpBaseFig() + 1));
+        VpAddSub(c, a, b, -1);
     }
     else {
-        GUARD_OBJ(c,VpCreateRbObject(mx *(VpBaseFig() + 1), "0", true));
-	if (!mx) {
-	    VpSetInf(c,VpGetSign(a));
-	}
-	else {
-	    VpAddSub(c, a, b, -1);
-	}
+        GUARD_OBJ(c, NewZeroWrapLimited(1, mx *(VpBaseFig() + 1)));
+        if (!mx) {
+            VpSetInf(c,VpGetSign(a));
+        }
+        else {
+            VpAddSub(c, a, b, -1);
+        }
     }
     return VpCheckGetValue(c);
 }
@@ -1581,7 +1773,7 @@ BigDecimal_neg(VALUE self)
     ENTER(5);
     Real *c, *a;
     GUARD_OBJ(a, GetVpValue(self, 1));
-    GUARD_OBJ(c, VpCreateRbObject(a->Prec *(VpBaseFig() + 1), "0", true));
+    GUARD_OBJ(c, NewZeroWrapLimited(1, a->Prec *(VpBaseFig() + 1)));
     VpAsgn(c, a, -1);
     return VpCheckGetValue(c);
 }
@@ -1608,7 +1800,7 @@ BigDecimal_mult(VALUE self, VALUE r)
     SAVE(b);
 
     mx = a->Prec + b->Prec;
-    GUARD_OBJ(c, VpCreateRbObject(mx *(VpBaseFig() + 1), "0", true));
+    GUARD_OBJ(c, NewZeroWrapLimited(1, mx * (VpBaseFig() + 1)));
     VpMult(c, a, b);
     return VpCheckGetValue(c);
 }
@@ -1655,8 +1847,8 @@ BigDecimal_divide(VALUE self, VALUE r, Real **c, Real **res, Real **div)
     if (2*BIGDECIMAL_DOUBLE_FIGURES > mx)
         mx = 2*BIGDECIMAL_DOUBLE_FIGURES;
 
-    GUARD_OBJ((*c), VpCreateRbObject(mx + 2*BASE_FIG, "#0", true));
-    GUARD_OBJ((*res), VpCreateRbObject((mx + 1)*2 + 2*BASE_FIG, "#0", true));
+    GUARD_OBJ((*c), NewZeroWrapNolimit(1, mx + 2*BASE_FIG));
+    GUARD_OBJ((*res), NewZeroWrapNolimit(1, (mx + 1)*2 + 2*BASE_FIG));
     VpDivd(*c, *res, a, b);
 
     return Qnil;
@@ -1721,7 +1913,7 @@ BigDecimal_quo(int argc, VALUE *argv, VALUE self)
 
     argc = rb_scan_args(argc, argv, "11", &value, &digits);
     if (argc > 1) {
-        n = GetPrecisionInt(digits);
+        n = check_int_precision(digits);
     }
 
     if (n > 0) {
@@ -1811,12 +2003,12 @@ BigDecimal_DoDivmod(VALUE self, VALUE r, Real **div, Real **mod)
     if (2*BIGDECIMAL_DOUBLE_FIGURES > mx)
         mx = 2*BIGDECIMAL_DOUBLE_FIGURES;
 
-    GUARD_OBJ(c, VpCreateRbObject(mx + 2*BASE_FIG, "0", true));
-    GUARD_OBJ(res, VpCreateRbObject(mx*2 + 2*BASE_FIG, "#0", true));
+    GUARD_OBJ(c, NewZeroWrapLimited(1, mx + 2*BASE_FIG));
+    GUARD_OBJ(res, NewZeroWrapNolimit(1, mx*2 + 2*BASE_FIG));
     VpDivd(c, res, a, b);
 
     mx = c->Prec * BASE_FIG;
-    GUARD_OBJ(d, VpCreateRbObject(mx, "0", true));
+    GUARD_OBJ(d, NewZeroWrapLimited(1, mx));
     VpActiveRound(d, c, VP_ROUND_DOWN, 0);
 
     VpMult(res, d, b);
@@ -1824,10 +2016,10 @@ BigDecimal_DoDivmod(VALUE self, VALUE r, Real **div, Real **mod)
 
     if (!VpIsZero(c) && (VpGetSign(a) * VpGetSign(b) < 0)) {
         /* result adjustment for negative case */
-        res = VpReallocReal(res, d->MaxPrec);
+        res = rbd_reallocate_struct(res, d->MaxPrec);
         res->MaxPrec = d->MaxPrec;
         VpAddSub(res, d, VpOne(), -1);
-        GUARD_OBJ(d, VpCreateRbObject(GetAddSubPrec(c, b) * 2*BASE_FIG, "0", true));
+        GUARD_OBJ(d, NewZeroWrapLimited(1, GetAddSubPrec(c, b) * 2*BASE_FIG));
         VpAddSub(d, c, b, 1);
         *div = res;
         *mod = d;
@@ -1891,17 +2083,17 @@ BigDecimal_divremain(VALUE self, VALUE r, Real **dv, Real **rv)
     SAVE(b);
 
     mx = (a->MaxPrec + b->MaxPrec) *VpBaseFig();
-    GUARD_OBJ(c,   VpCreateRbObject(mx, "0", true));
-    GUARD_OBJ(res, VpCreateRbObject((mx+1) * 2 + (VpBaseFig() + 1), "#0", true));
-    GUARD_OBJ(rr,  VpCreateRbObject((mx+1) * 2 + (VpBaseFig() + 1), "#0", true));
-    GUARD_OBJ(ff,  VpCreateRbObject((mx+1) * 2 + (VpBaseFig() + 1), "#0", true));
+    GUARD_OBJ(c,   NewZeroWrapLimited(1, mx));
+    GUARD_OBJ(res, NewZeroWrapNolimit(1, (mx+1) * 2 + (VpBaseFig() + 1)));
+    GUARD_OBJ(rr,  NewZeroWrapNolimit(1, (mx+1) * 2 + (VpBaseFig() + 1)));
+    GUARD_OBJ(ff,  NewZeroWrapNolimit(1, (mx+1) * 2 + (VpBaseFig() + 1)));
 
     VpDivd(c, res, a, b);
 
     mx = c->Prec *(VpBaseFig() + 1);
 
-    GUARD_OBJ(d, VpCreateRbObject(mx, "0", true));
-    GUARD_OBJ(f, VpCreateRbObject(mx, "0", true));
+    GUARD_OBJ(d, NewZeroWrapLimited(1, mx));
+    GUARD_OBJ(f, NewZeroWrapLimited(1, mx));
 
     VpActiveRound(d, c, VP_ROUND_DOWN, 0); /* 0: round off */
 
@@ -1986,7 +2178,7 @@ BigDecimal_div2(VALUE self, VALUE b, VALUE n)
     }
 
     /* div in BigDecimal sense */
-    ix = GetPrecisionInt(n);
+    ix = check_int_precision(n);
     if (ix == 0) {
         return BigDecimal_div(self, b);
     }
@@ -1997,7 +2189,7 @@ BigDecimal_div2(VALUE self, VALUE b, VALUE n)
         size_t b_prec = ix;
         size_t pl = VpSetPrecLimit(0);
 
-        GUARD_OBJ(cv, VpCreateRbObject(mx + VpBaseFig(), "0", true));
+        GUARD_OBJ(cv, NewZeroWrapLimited(1, mx + VpBaseFig()));
         GUARD_OBJ(av, GetVpValue(self, 1));
         /* TODO: I want to refactor this precision control for a float value later
          *       by introducing an implicit conversion function instead of
@@ -2008,7 +2200,7 @@ BigDecimal_div2(VALUE self, VALUE b, VALUE n)
         GUARD_OBJ(bv, GetVpValueWithPrec(b, b_prec, 1));
         mx = av->Prec + bv->Prec + 2;
         if (mx <= cv->MaxPrec) mx = cv->MaxPrec + 1;
-        GUARD_OBJ(res, VpCreateRbObject((mx * 2  + 2)*VpBaseFig(), "#0", true));
+        GUARD_OBJ(res, NewZeroWrapNolimit(1, (mx * 2  + 2)*VpBaseFig()));
         VpDivd(cv, res, av, bv);
         VpSetPrecLimit(pl);
         VpLeftRound(cv, VpGetRoundMode(), ix);
@@ -2091,7 +2283,7 @@ BigDecimal_add2(VALUE self, VALUE b, VALUE n)
 {
     ENTER(2);
     Real *cv;
-    SIGNED_VALUE mx = GetPrecisionInt(n);
+    SIGNED_VALUE mx = check_int_precision(n);
     if (mx == 0) return BigDecimal_add(self, b);
     else {
 	size_t pl = VpSetPrecLimit(0);
@@ -2121,7 +2313,7 @@ BigDecimal_sub2(VALUE self, VALUE b, VALUE n)
 {
     ENTER(2);
     Real *cv;
-    SIGNED_VALUE mx = GetPrecisionInt(n);
+    SIGNED_VALUE mx = check_int_precision(n);
     if (mx == 0) return BigDecimal_sub(self, b);
     else {
 	size_t pl = VpSetPrecLimit(0);
@@ -2164,7 +2356,7 @@ BigDecimal_mult2(VALUE self, VALUE b, VALUE n)
 {
     ENTER(2);
     Real *cv;
-    SIGNED_VALUE mx = GetPrecisionInt(n);
+    SIGNED_VALUE mx = check_int_precision(n);
     if (mx == 0) return BigDecimal_mult(self, b);
     else {
 	size_t pl = VpSetPrecLimit(0);
@@ -2196,7 +2388,7 @@ BigDecimal_abs(VALUE self)
 
     GUARD_OBJ(a, GetVpValue(self, 1));
     mx = a->Prec *(VpBaseFig() + 1);
-    GUARD_OBJ(c, VpCreateRbObject(mx, "0", true));
+    GUARD_OBJ(c, NewZeroWrapLimited(1, mx));
     VpAsgn(c, a, 1);
     VpChangeSign(c, 1);
     return VpCheckGetValue(c);
@@ -2219,9 +2411,10 @@ BigDecimal_sqrt(VALUE self, VALUE nFig)
     GUARD_OBJ(a, GetVpValue(self, 1));
     mx = a->Prec * (VpBaseFig() + 1);
 
-    n = GetPrecisionInt(nFig) + VpDblFig() + BASE_FIG;
+    n = check_int_precision(nFig);
+    n += VpDblFig() + VpBaseFig();
     if (mx <= n) mx = n;
-    GUARD_OBJ(c, VpCreateRbObject(mx, "0", true));
+    GUARD_OBJ(c, NewZeroWrapLimited(1, mx));
     VpSqrt(c, a);
     return VpCheckGetValue(c);
 }
@@ -2237,7 +2430,7 @@ BigDecimal_fix(VALUE self)
 
     GUARD_OBJ(a, GetVpValue(self, 1));
     mx = a->Prec *(VpBaseFig() + 1);
-    GUARD_OBJ(c, VpCreateRbObject(mx, "0", true));
+    GUARD_OBJ(c, NewZeroWrapLimited(1, mx));
     VpActiveRound(c, a, VP_ROUND_DOWN, 0); /* 0: round off */
     return VpCheckGetValue(c);
 }
@@ -2310,7 +2503,7 @@ BigDecimal_round(int argc, VALUE *argv, VALUE self)
     pl = VpSetPrecLimit(0);
     GUARD_OBJ(a, GetVpValue(self, 1));
     mx = a->Prec * (VpBaseFig() + 1);
-    GUARD_OBJ(c, VpCreateRbObject(mx, "0", true));
+    GUARD_OBJ(c, NewZeroWrapLimited(1, mx));
     VpSetPrecLimit(pl);
     VpActiveRound(c, a, sw, iLoc);
     if (round_to_int) {
@@ -2356,7 +2549,7 @@ BigDecimal_truncate(int argc, VALUE *argv, VALUE self)
 
     GUARD_OBJ(a, GetVpValue(self, 1));
     mx = a->Prec * (VpBaseFig() + 1);
-    GUARD_OBJ(c, VpCreateRbObject(mx, "0", true));
+    GUARD_OBJ(c, NewZeroWrapLimited(1, mx));
     VpSetPrecLimit(pl);
     VpActiveRound(c, a, VP_ROUND_DOWN, iLoc); /* 0: truncate */
     if (argc == 0) {
@@ -2376,7 +2569,7 @@ BigDecimal_frac(VALUE self)
 
     GUARD_OBJ(a, GetVpValue(self, 1));
     mx = a->Prec * (VpBaseFig() + 1);
-    GUARD_OBJ(c, VpCreateRbObject(mx, "0", true));
+    GUARD_OBJ(c, NewZeroWrapLimited(1, mx));
     VpFrac(c, a);
     return VpCheckGetValue(c);
 }
@@ -2416,7 +2609,7 @@ BigDecimal_floor(int argc, VALUE *argv, VALUE self)
 
     GUARD_OBJ(a, GetVpValue(self, 1));
     mx = a->Prec * (VpBaseFig() + 1);
-    GUARD_OBJ(c, VpCreateRbObject(mx, "0", true));
+    GUARD_OBJ(c, NewZeroWrapLimited(1, mx));
     VpSetPrecLimit(pl);
     VpActiveRound(c, a, VP_ROUND_FLOOR, iLoc);
 #ifdef BIGDECIMAL_DEBUG
@@ -2462,7 +2655,7 @@ BigDecimal_ceil(int argc, VALUE *argv, VALUE self)
 
     GUARD_OBJ(a, GetVpValue(self, 1));
     mx = a->Prec * (VpBaseFig() + 1);
-    GUARD_OBJ(c, VpCreateRbObject(mx, "0", true));
+    GUARD_OBJ(c, NewZeroWrapLimited(1, mx));
     VpSetPrecLimit(pl);
     VpActiveRound(c, a, VP_ROUND_CEIL, iLoc);
     if (argc == 0) {
@@ -2566,10 +2759,10 @@ BigDecimal_to_s(int argc, VALUE *argv, VALUE self)
     psz = RSTRING_PTR(str);
 
     if (fmt) {
-	VpToFString(vp, psz, mc, fPlus);
+	VpToFString(vp, psz, RSTRING_LEN(str), mc, fPlus);
     }
     else {
-	VpToString (vp, psz, mc, fPlus);
+	VpToString (vp, psz, RSTRING_LEN(str), mc, fPlus);
     }
     rb_str_resize(str, strlen(psz));
     return str;
@@ -2611,7 +2804,7 @@ BigDecimal_split(VALUE self)
     GUARD_OBJ(vp, GetVpValue(self, 1));
     str = rb_str_new(0, VpNumOfChars(vp, "E"));
     psz1 = RSTRING_PTR(str);
-    VpSzMantissa(vp, psz1);
+    VpSzMantissa(vp, psz1, RSTRING_LEN(str));
     s = 1;
     if(psz1[0] == '-') {
 	size_t len = strlen(psz1 + 1);
@@ -2660,7 +2853,7 @@ BigDecimal_inspect(VALUE self)
     nc = VpNumOfChars(vp, "E");
 
     str = rb_str_new(0, nc);
-    VpToString(vp, RSTRING_PTR(str), 0, 0);
+    VpToString(vp, RSTRING_PTR(str), RSTRING_LEN(str), 0, 0);
     rb_str_resize(str, strlen(RSTRING_PTR(str)));
     return str;
 }
@@ -2770,7 +2963,7 @@ bigdecimal_power_by_bigdecimal(Real const* x, Real const* exp, ssize_t const n)
     volatile VALUE obj = exp->obj;
 
     if (VpIsZero(exp)) {
-        return VpCheckGetValue(VpCreateRbObject(n, "1", true));
+        return VpCheckGetValue(NewOneWrapLimited(1, n));
     }
 
     log_x = BigMath_log(x->obj, SSIZET2NUM(n+1));
@@ -2808,9 +3001,9 @@ BigDecimal_power(int argc, VALUE*argv, VALUE self)
     n = NIL_P(prec) ? (ssize_t)(x->Prec*VpBaseFig()) : NUM2SSIZET(prec);
 
     if (VpIsNaN(x)) {
-        y = VpCreateRbObject(n, "0", true);
-	RB_GC_GUARD(y->obj);
-	VpSetNaN(y);
+        y = NewZeroWrapLimited(1, n);
+        VpSetNaN(y);
+        RB_GC_GUARD(y->obj);
         return VpCheckGetValue(y);
     }
 
@@ -2879,136 +3072,126 @@ BigDecimal_power(int argc, VALUE*argv, VALUE self)
     }
 
     if (VpIsZero(x)) {
-	if (is_negative(vexp)) {
-            y = VpCreateRbObject(n, "#0", true);
-	    RB_GC_GUARD(y->obj);
-	    if (BIGDECIMAL_NEGATIVE_P(x)) {
-		if (is_integer(vexp)) {
-		    if (is_even(vexp)) {
-			/* (-0) ** (-even_integer)  -> Infinity */
-			VpSetPosInf(y);
-		    }
-		    else {
-			/* (-0) ** (-odd_integer)  -> -Infinity */
-			VpSetNegInf(y);
-		    }
-		}
-		else {
-		    /* (-0) ** (-non_integer)  -> Infinity */
-		    VpSetPosInf(y);
-		}
-	    }
-	    else {
-		/* (+0) ** (-num)  -> Infinity */
-		VpSetPosInf(y);
-	    }
+        if (is_negative(vexp)) {
+            y = NewZeroWrapNolimit(1, n);
+            if (BIGDECIMAL_NEGATIVE_P(x)) {
+                if (is_integer(vexp)) {
+                    if (is_even(vexp)) {
+                        /* (-0) ** (-even_integer)  -> Infinity */
+                        VpSetPosInf(y);
+                    }
+                    else {
+                        /* (-0) ** (-odd_integer)  -> -Infinity */
+                        VpSetNegInf(y);
+                    }
+                }
+                else {
+                    /* (-0) ** (-non_integer)  -> Infinity */
+                    VpSetPosInf(y);
+                }
+            }
+            else {
+                /* (+0) ** (-num)  -> Infinity */
+                VpSetPosInf(y);
+            }
+            RB_GC_GUARD(y->obj);
             return VpCheckGetValue(y);
-	}
-	else if (is_zero(vexp)) {
-            return VpCheckGetValue(VpCreateRbObject(n, "1", true));
-	}
-	else {
-            return VpCheckGetValue(VpCreateRbObject(n, "0", true));
-	}
+        }
+        else if (is_zero(vexp)) {
+            return VpCheckGetValue(NewOneWrapLimited(1, n));
+        }
+        else {
+            return VpCheckGetValue(NewZeroWrapLimited(1, n));
+        }
     }
 
     if (is_zero(vexp)) {
-        return VpCheckGetValue(VpCreateRbObject(n, "1", true));
+        return VpCheckGetValue(NewOneWrapLimited(1, n));
     }
     else if (is_one(vexp)) {
-	return self;
+        return self;
     }
 
     if (VpIsInf(x)) {
-	if (is_negative(vexp)) {
-	    if (BIGDECIMAL_NEGATIVE_P(x)) {
-		if (is_integer(vexp)) {
-		    if (is_even(vexp)) {
-			/* (-Infinity) ** (-even_integer) -> +0 */
-                        return VpCheckGetValue(VpCreateRbObject(n, "0", true));
-		    }
-		    else {
-			/* (-Infinity) ** (-odd_integer) -> -0 */
-                        return VpCheckGetValue(VpCreateRbObject(n, "-0", true));
-		    }
-		}
-		else {
-		    /* (-Infinity) ** (-non_integer) -> -0 */
-                    return VpCheckGetValue(VpCreateRbObject(n, "-0", true));
-		}
-	    }
-	    else {
-                return VpCheckGetValue(VpCreateRbObject(n, "0", true));
-	    }
-	}
-	else {
-            y = VpCreateRbObject(n, "0", true);
-	    if (BIGDECIMAL_NEGATIVE_P(x)) {
-		if (is_integer(vexp)) {
-		    if (is_even(vexp)) {
-			VpSetPosInf(y);
-		    }
-		    else {
-			VpSetNegInf(y);
-		    }
-		}
-		else {
-		    /* TODO: support complex */
-		    rb_raise(rb_eMathDomainError,
-			     "a non-integral exponent for a negative base");
-		}
-	    }
-	    else {
-		VpSetPosInf(y);
-	    }
+        if (is_negative(vexp)) {
+            if (BIGDECIMAL_NEGATIVE_P(x)) {
+                if (is_integer(vexp)) {
+                    if (is_even(vexp)) {
+                        /* (-Infinity) ** (-even_integer) -> +0 */
+                        return VpCheckGetValue(NewZeroWrapLimited(1, n));
+                    }
+                    else {
+                        /* (-Infinity) ** (-odd_integer) -> -0 */
+                        return VpCheckGetValue(NewZeroWrapLimited(-1, n));
+                    }
+                }
+                else {
+                    /* (-Infinity) ** (-non_integer) -> -0 */
+                    return VpCheckGetValue(NewZeroWrapLimited(-1, n));
+                }
+            }
+            else {
+                return VpCheckGetValue(NewZeroWrapLimited(1, n));
+            }
+        }
+        else {
+            y = NewZeroWrapLimited(1, n);
+            if (BIGDECIMAL_NEGATIVE_P(x)) {
+                if (is_integer(vexp)) {
+                    if (is_even(vexp)) {
+                        VpSetPosInf(y);
+                    }
+                    else {
+                        VpSetNegInf(y);
+                    }
+                }
+                else {
+                    /* TODO: support complex */
+                    rb_raise(rb_eMathDomainError,
+                            "a non-integral exponent for a negative base");
+                }
+            }
+            else {
+                VpSetPosInf(y);
+            }
             return VpCheckGetValue(y);
-	}
+        }
     }
 
     if (exp != NULL) {
-	return bigdecimal_power_by_bigdecimal(x, exp, n);
+        return bigdecimal_power_by_bigdecimal(x, exp, n);
     }
     else if (RB_TYPE_P(vexp, T_BIGNUM)) {
-	VALUE abs_value = BigDecimal_abs(self);
-	if (is_one(abs_value)) {
-            return VpCheckGetValue(VpCreateRbObject(n, "1", true));
-	}
-	else if (RTEST(rb_funcall(abs_value, '<', 1, INT2FIX(1)))) {
-	    if (is_negative(vexp)) {
-                y = VpCreateRbObject(n, "0", true);
-		if (is_even(vexp)) {
-		    VpSetInf(y, VpGetSign(x));
-		}
-		else {
-		    VpSetInf(y, -VpGetSign(x));
-		}
+        VALUE abs_value = BigDecimal_abs(self);
+        if (is_one(abs_value)) {
+            return VpCheckGetValue(NewOneWrapLimited(1, n));
+        }
+        else if (RTEST(rb_funcall(abs_value, '<', 1, INT2FIX(1)))) {
+            if (is_negative(vexp)) {
+                y = NewZeroWrapLimited(1, n);
+                VpSetInf(y, (is_even(vexp) ? 1 : -1) * VpGetSign(x));
                 return VpCheckGetValue(y);
-	    }
-	    else if (BIGDECIMAL_NEGATIVE_P(x) && is_even(vexp)) {
-                return VpCheckGetValue(VpCreateRbObject(n, "-0", true));
-	    }
-	    else {
-                return VpCheckGetValue(VpCreateRbObject(n, "0", true));
-	    }
-	}
-	else {
-	    if (is_positive(vexp)) {
-                y = VpCreateRbObject(n, "0", true);
-		if (is_even(vexp)) {
-		    VpSetInf(y, VpGetSign(x));
-		}
-		else {
-		    VpSetInf(y, -VpGetSign(x));
-		}
+            }
+            else if (BIGDECIMAL_NEGATIVE_P(x) && is_even(vexp)) {
+                return VpCheckGetValue(NewZeroWrapLimited(-1, n));
+            }
+            else {
+                return VpCheckGetValue(NewZeroWrapLimited(1, n));
+            }
+        }
+        else {
+            if (is_positive(vexp)) {
+                y = NewZeroWrapLimited(1, n);
+                VpSetInf(y, (is_even(vexp) ? 1 : -1) * VpGetSign(x));
                 return VpCheckGetValue(y);
-	    }
-	    else if (BIGDECIMAL_NEGATIVE_P(x) && is_even(vexp)) {
-                return VpCheckGetValue(VpCreateRbObject(n, "-0", true));
-	    }
-	    else {
-                return VpCheckGetValue(VpCreateRbObject(n, "0", true));
-	    }
-	}
+            }
+            else if (BIGDECIMAL_NEGATIVE_P(x) && is_even(vexp)) {
+                return VpCheckGetValue(NewZeroWrapLimited(-1, n));
+            }
+            else {
+                return VpCheckGetValue(NewZeroWrapLimited(1, n));
+            }
+        }
     }
 
     int_exp = FIX2LONG(vexp);
@@ -3017,15 +3200,15 @@ BigDecimal_power(int argc, VALUE*argv, VALUE self)
     if (ma == 0) ma = 1;
 
     if (VpIsDef(x)) {
-	mp = x->Prec * (VpBaseFig() + 1);
-        GUARD_OBJ(y, VpCreateRbObject(mp * (ma + 1), "0", true));
+        mp = x->Prec * (VpBaseFig() + 1);
+        GUARD_OBJ(y, NewZeroWrapLimited(1, mp * (ma + 1)));
     }
     else {
-        GUARD_OBJ(y, VpCreateRbObject(1, "0", true));
+        GUARD_OBJ(y, NewZeroWrapLimited(1, 1));
     }
     VpPowerByInt(y, x, int_exp);
     if (!NIL_P(prec) && VpIsDef(y)) {
-	VpMidRound(y, VpGetRoundMode(), n);
+        VpMidRound(y, VpGetRoundMode(), n);
     }
     return VpCheckGetValue(y);
 }
@@ -3114,7 +3297,7 @@ rb_uint64_convert_to_BigDecimal(uint64_t uval, RB_UNUSED_VAR(size_t digs), int r
 
     Real *vp;
     if (uval == 0) {
-        vp = VpAllocReal(1);
+        vp = rbd_allocate_struct(1);
         vp->MaxPrec = 1;
         vp->Prec = 1;
         vp->exponent = 1;
@@ -3122,7 +3305,7 @@ rb_uint64_convert_to_BigDecimal(uint64_t uval, RB_UNUSED_VAR(size_t digs), int r
         vp->frac[0] = 0;
     }
     else if (uval < BASE) {
-        vp = VpAllocReal(1);
+        vp = rbd_allocate_struct(1);
         vp->MaxPrec = 1;
         vp->Prec = 1;
         vp->exponent = 1;
@@ -3148,7 +3331,7 @@ rb_uint64_convert_to_BigDecimal(uint64_t uval, RB_UNUSED_VAR(size_t digs), int r
         }
 
         const size_t exp = len + ntz;
-        vp = VpAllocReal(len);
+        vp = rbd_allocate_struct(len);
         vp->MaxPrec = len;
         vp->Prec = len;
         vp->exponent = exp;
@@ -3281,7 +3464,7 @@ rb_float_convert_to_BigDecimal(VALUE val, size_t digs, int raise_exception)
 
     VALUE inum;
     size_t RB_UNUSED_VAR(prec) = 0;
-    size_t exp = 0;
+    SIGNED_VALUE exp = 0;
     if (decpt > 0) {
         if (decpt < len10) {
             /*
@@ -3493,12 +3676,15 @@ rb_convert_to_BigDecimal(VALUE val, size_t digs, int raise_exception)
  *    BigDecimal(value, exception: true) -> bigdecimal
  *    BigDecimal(value, ndigits, exception: true) -> bigdecimal
  *
- *   Returns the \BigDecimal converted from +value+
- *   with a precision of +ndigits+ decimal digits.
+ *  Returns the \BigDecimal converted from +value+
+ *  with a precision of +ndigits+ decimal digits.
+ *
+ *  When +ndigits+ is less than the number of significant digits
+ *  in the value, the result is rounded to that number of digits,
+ *  according to the current rounding mode; see BigDecimal.mode.
  *
- *   When +ndigits+ is less than the number of significant digits
- *   in the value, the result is rounded to that number of digits,
- *   according to the current rounding mode; see BigDecimal.mode.
+ *  When +ndigits+ is 0, the number of digits to correctly represent a float number
+ *  is determined automatically.
  *
  *  Returns +value+ converted to a \BigDecimal, depending on the type of +value+:
  *
@@ -3606,8 +3792,10 @@ BigDecimal_limit(int argc, VALUE *argv, VALUE self)
 
 /* Returns the sign of the value.
  *
- * Returns a positive value if > 0, a negative value if < 0, and a
- * zero if == 0.
+ * Returns a positive value if > 0, a negative value if < 0.
+ * It behaves the same with zeros -
+ * it returns a positive value for a positive zero (BigDecimal('0')) and
+ * a negative value for a negative zero (BigDecimal('-0')).
  *
  * The specific value returned indicates the type and sign of the BigDecimal,
  * as follows:
@@ -3771,18 +3959,16 @@ BigMath_s_exp(VALUE klass, VALUE x, VALUE vprec)
             return VpCheckGetValue(GetVpValueWithPrec(INT2FIX(0), prec, 1));
 	}
 	else {
-	    Real* vy;
-            vy = VpCreateRbObject(prec, "#0", true);
+	    Real* vy = NewZeroWrapNolimit(1, prec);
 	    VpSetInf(vy, VP_SIGN_POSITIVE_INFINITE);
 	    RB_GC_GUARD(vy->obj);
             return VpCheckGetValue(vy);
 	}
     }
     else if (nan) {
-	Real* vy;
-        vy = VpCreateRbObject(prec, "#0", true);
-	VpSetNaN(vy);
-	RB_GC_GUARD(vy->obj);
+        Real* vy = NewZeroWrapNolimit(1, prec);
+        VpSetNaN(vy);
+        RB_GC_GUARD(vy->obj);
         return VpCheckGetValue(vy);
     }
     else if (vx == NULL) {
@@ -3800,7 +3986,7 @@ BigMath_s_exp(VALUE klass, VALUE x, VALUE vprec)
 	VpSetSign(vx, 1);
     }
 
-    one = VpCheckGetValue(VpCreateRbObject(1, "1", true));
+    one = VpCheckGetValue(NewOneWrapLimited(1, 1));
     y   = one;
     d   = y;
     i   = 1;
@@ -3927,15 +4113,13 @@ get_vp_value:
 	break;
     }
     if (infinite && !negative) {
-	Real* vy;
-        vy = VpCreateRbObject(prec, "#0", true);
+        Real *vy = NewZeroWrapNolimit(1, prec);
 	RB_GC_GUARD(vy->obj);
 	VpSetInf(vy, VP_SIGN_POSITIVE_INFINITE);
         return VpCheckGetValue(vy);
     }
     else if (nan) {
-	Real* vy;
-        vy = VpCreateRbObject(prec, "#0", true);
+	Real* vy = NewZeroWrapNolimit(1, prec);
 	RB_GC_GUARD(vy->obj);
 	VpSetNaN(vy);
         return VpCheckGetValue(vy);
@@ -3949,7 +4133,7 @@ get_vp_value:
     }
     x = VpCheckGetValue(vx);
 
-    RB_GC_GUARD(one) = VpCheckGetValue(VpCreateRbObject(1, "1", true));
+    RB_GC_GUARD(one) = VpCheckGetValue(NewOneWrapLimited(1, 1));
     RB_GC_GUARD(two) = VpCheckGetValue(VpCreateRbObject(1, "2", true));
 
     n = prec + BIGDECIMAL_DOUBLE_FIGURES;
@@ -4414,20 +4598,31 @@ Init_bigdecimal(void)
     rb_define_singleton_method(rb_mBigMath, "exp", BigMath_s_exp, 2);
     rb_define_singleton_method(rb_mBigMath, "log", BigMath_s_log, 2);
 
-    id_up = rb_intern_const("up");
-    id_down = rb_intern_const("down");
-    id_truncate = rb_intern_const("truncate");
-    id_half_up = rb_intern_const("half_up");
-    id_default = rb_intern_const("default");
-    id_half_down = rb_intern_const("half_down");
-    id_half_even = rb_intern_const("half_even");
-    id_banker = rb_intern_const("banker");
-    id_ceiling = rb_intern_const("ceiling");
-    id_ceil = rb_intern_const("ceil");
-    id_floor = rb_intern_const("floor");
+#define ROUNDING_MODE(i, name, value) \
+    id_##name = rb_intern_const(#name); \
+    rbd_rounding_modes[i].id   = id_##name; \
+    rbd_rounding_modes[i].mode = value;
+
+    ROUNDING_MODE(0, up,        RBD_ROUND_UP);
+    ROUNDING_MODE(1, down,      RBD_ROUND_DOWN);
+    ROUNDING_MODE(2, half_up,   RBD_ROUND_HALF_UP);
+    ROUNDING_MODE(3, half_down, RBD_ROUND_HALF_DOWN);
+    ROUNDING_MODE(4, ceil,      RBD_ROUND_CEIL);
+    ROUNDING_MODE(5, floor,     RBD_ROUND_FLOOR);
+    ROUNDING_MODE(6, half_even, RBD_ROUND_HALF_EVEN);
+
+    ROUNDING_MODE(7,  default,   RBD_ROUND_DEFAULT);
+    ROUNDING_MODE(8,  truncate,  RBD_ROUND_TRUNCATE);
+    ROUNDING_MODE(9,  banker,    RBD_ROUND_BANKER);
+    ROUNDING_MODE(10, ceiling,   RBD_ROUND_CEILING);
+
+#undef ROUNDING_MODE
+
     id_to_r = rb_intern_const("to_r");
     id_eq = rb_intern_const("==");
     id_half = rb_intern_const("half");
+
+    (void)VPrint;  /* suppress unused warning */
 }
 
 /*
@@ -4447,7 +4642,7 @@ static int gfCheckVal = 1;      /* Value checking flag in VpNmlz()  */
 #endif /* BIGDECIMAL_DEBUG */
 
 static Real *VpConstOne;    /* constant 1.0 */
-static Real *VpPt5;        /* constant 0.5 */
+static Real *VpConstPt5;    /* constant 0.5 */
 #define maxnr 100UL    /* Maximum iterations for calculating sqrt. */
                 /* used in VpSqrt() */
 
@@ -4478,42 +4673,6 @@ static int VpRdup(Real *m, size_t ind_m);
 static int gnAlloc = 0; /* Memory allocation counter */
 #endif /* BIGDECIMAL_DEBUG */
 
-VP_EXPORT void *
-VpMemAlloc(size_t mb)
-{
-    void *p = xmalloc(mb);
-    memset(p, 0, mb);
-#ifdef BIGDECIMAL_DEBUG
-    gnAlloc++; /* Count allocation call */
-#endif /* BIGDECIMAL_DEBUG */
-    return p;
-}
-
-VP_EXPORT void *
-VpMemRealloc(void *ptr, size_t mb)
-{
-    return xrealloc(ptr, mb);
-}
-
-VP_EXPORT void
-VpFree(Real *pv)
-{
-    if (pv != NULL) {
-	xfree(pv);
-#ifdef BIGDECIMAL_DEBUG
-	gnAlloc--; /* Decrement allocation count */
-	if (gnAlloc == 0) {
-	    printf(" *************** All memories allocated freed ****************\n");
-	    /*getchar();*/
-	}
-	if (gnAlloc <  0) {
-	    printf(" ??????????? Too many memory free calls(%d) ?????????????\n", gnAlloc);
-	    /*getchar();*/
-	}
-#endif /* BIGDECIMAL_DEBUG */
-    }
-}
-
 /*
  * EXCEPTION Handling.
  */
@@ -4902,9 +5061,13 @@ VpInit(DECDIG BaseVal)
     /* Setup +/- Inf  NaN -0 */
     VpGetDoubleNegZero();
 
-    /* Allocates Vp constants. */
-    VpConstOne = VpAlloc(1UL, "1", 1, 1);
-    VpPt5 = VpAlloc(1UL, ".5", 1, 1);
+    /* Const 1.0 */
+    VpConstOne = NewOneNolimit(1, 1);
+
+    /* Const 0.5 */
+    VpConstPt5 = NewOneNolimit(1, 1);
+    VpConstPt5->exponent = 0;
+    VpConstPt5->frac[0] = 5*BASE1;
 
 #ifdef BIGDECIMAL_DEBUG
     gnAlloc = 0;
@@ -4993,7 +5156,7 @@ bigdecimal_parse_special_string(const char *str)
         p = str + table[i].len;
         while (*p && ISSPACE(*p)) ++p;
         if (*p == '\0') {
-            Real *vp = VpAllocReal(1);
+            Real *vp = rbd_allocate_struct(1);
             vp->MaxPrec = 1;
             switch (table[i].sign) {
               default:
@@ -5017,11 +5180,11 @@ bigdecimal_parse_special_string(const char *str)
 /*
  * Allocates variable.
  * [Input]
- *   mx ... allocation unit, if zero then mx is determined by szVal.
- *    The mx is the number of effective digits can to be stored.
- *   szVal ... value assigned(char). If szVal==NULL,then zero is assumed.
- *            If szVal[0]=='#' then Max. Prec. will not be considered(1.1.7),
- *            full precision specified by szVal is allocated.
+ *   mx ... The number of decimal digits to be allocated, if zero then mx is determined by szVal.
+ *          The mx will be the number of significant digits can to be stored.
+ *   szVal ... The value assigned(char). If szVal==NULL, then zero is assumed.
+ *             If szVal[0]=='#' then MaxPrec is not affected by the precision limit
+ *             so that the full precision specified by szVal is allocated.
  *
  * [Returns]
  *   Pointer to the newly allocated variable, or
@@ -5032,48 +5195,40 @@ VpAlloc(size_t mx, const char *szVal, int strict_p, int exc)
 {
     const char *orig_szVal = szVal;
     size_t i, j, ni, ipf, nf, ipe, ne, dot_seen, exp_seen, nalloc;
+    size_t len;
     char v, *psz;
     int  sign=1;
     Real *vp = NULL;
-    size_t mf = VpGetPrecLimit();
     VALUE buf;
 
-    mx = (mx + BASE_FIG - 1) / BASE_FIG;    /* Determine allocation unit. */
-    if (mx == 0) ++mx;
-
-    if (szVal) {
-        /* Skipping leading spaces */
-        while (ISSPACE(*szVal)) szVal++;
-
-        /* Processing the leading one `#` */
-        if (*szVal != '#') {
-            if (mf) {
-                mf = (mf + BASE_FIG - 1) / BASE_FIG + 2; /* Needs 1 more for div */
-                if (mx > mf) {
-                    mx = mf;
-                }
-            }
-        }
-        else {
-            ++szVal;
-        }
-    }
-    else {
+    if (szVal == NULL) {
       return_zero:
         /* necessary to be able to store */
         /* at least mx digits. */
         /* szVal==NULL ==> allocate zero value. */
-        vp = VpAllocReal(mx);
-        vp->MaxPrec = mx;    /* set max precision */
+        vp = rbd_allocate_struct(mx);
+        vp->MaxPrec = rbd_calculate_internal_digits(mx, false);  /* Must false */
         VpSetZero(vp, 1);    /* initialize vp to zero. */
         return vp;
     }
 
+    /* Skipping leading spaces */
+    while (ISSPACE(*szVal)) szVal++;
+
     /* Check on Inf & NaN */
     if ((vp = bigdecimal_parse_special_string(szVal)) != NULL) {
         return vp;
     }
 
+    /* Processing the leading one `#` */
+    if (*szVal != '#') {
+        len = rbd_calculate_internal_digits(mx, true);
+    }
+    else {
+        len = rbd_calculate_internal_digits(mx, false);
+        ++szVal;
+    }
+
     /* Scanning digits */
 
     /* A buffer for keeping scanned digits */
@@ -5235,11 +5390,11 @@ VpAlloc(size_t mx, const char *szVal, int strict_p, int exc)
 
     nalloc = (ni + nf + BASE_FIG - 1) / BASE_FIG + 1;    /* set effective allocation  */
     /* units for szVal[]  */
-    if (mx == 0) mx = 1;
-    nalloc = Max(nalloc, mx);
-    mx = nalloc;
-    vp = VpAllocReal(mx);
-    vp->MaxPrec = mx;        /* set max precision */
+    if (len == 0) len = 1;
+    nalloc = Max(nalloc, len);
+    len = nalloc;
+    vp = rbd_allocate_struct(len);
+    vp->MaxPrec = len;        /* set max precision */
     VpSetZero(vp, sign);
     VpCtoV(vp, psz, ni, psz + ipf, nf, psz + ipe, ne);
     rb_str_resize(buf, 0);
@@ -5804,7 +5959,7 @@ VpMult(Real *c, Real *a, Real *b)
 
     if (MxIndC < MxIndAB) {    /* The Max. prec. of c < Prec(a)+Prec(b) */
 	w = c;
-	c = VpAlloc((size_t)((MxIndAB + 1) * BASE_FIG), "#0", 1, 1);
+        c = NewZeroNolimit(1, (size_t)((MxIndAB + 1) * BASE_FIG));
 	MxIndC = MxIndAB;
     }
 
@@ -5812,8 +5967,8 @@ VpMult(Real *c, Real *a, Real *b)
 
     c->exponent = a->exponent;    /* set exponent */
     if (!AddExponent(c, b->exponent)) {
-	if (w) VpFree(c);
-	return 0;
+        if (w) rbd_free_struct(c);
+        return 0;
     }
     VpSetSign(c, VpGetSign(a) * VpGetSign(b));    /* set sign  */
     carry = 0;
@@ -5863,10 +6018,10 @@ VpMult(Real *c, Real *a, Real *b)
 	}
     }
     if (w != NULL) {        /* free work variable */
-	VpNmlz(c);
-	VpAsgn(w, c, 1);
-	VpFree(c);
-	c = w;
+        VpNmlz(c);
+        VpAsgn(w, c, 1);
+        rbd_free_struct(c);
+        c = w;
     }
     else {
 	VpLimitRound(c,0);
@@ -6235,7 +6390,6 @@ Exit:
  *     Note: % must not appear more than once
  *    a  ... VP variable to be printed
  */
-#ifdef BIGDECIMAL_ENABLE_VPRINT
 static int
 VPrint(FILE *fp, const char *cntl_chr, Real *a)
 {
@@ -6248,95 +6402,94 @@ VPrint(FILE *fp, const char *cntl_chr, Real *a)
     /*  nc : number of characters printed  */
     ZeroSup = 1;        /* Flag not to print the leading zeros as 0.00xxxxEnn */
     while (*(cntl_chr + j)) {
-	if (*(cntl_chr + j) == '%' && *(cntl_chr + j + 1) != '%') {
-	    nc = 0;
-	    if (VpIsNaN(a)) {
-		fprintf(fp, SZ_NaN);
-		nc += 8;
-	    }
-	    else if (VpIsPosInf(a)) {
-		fprintf(fp, SZ_INF);
-		nc += 8;
-	    }
-	    else if (VpIsNegInf(a)) {
-		fprintf(fp, SZ_NINF);
-		nc += 9;
-	    }
-	    else if (!VpIsZero(a)) {
-		if (BIGDECIMAL_NEGATIVE_P(a)) {
-		    fprintf(fp, "-");
-		    ++nc;
-		}
-		nc += fprintf(fp, "0.");
-		switch (*(cntl_chr + j + 1)) {
-		default:
-		    break;
+        if (*(cntl_chr + j) == '%' && *(cntl_chr + j + 1) != '%') {
+            nc = 0;
+            if (VpIsNaN(a)) {
+                fprintf(fp, SZ_NaN);
+                nc += 8;
+            }
+            else if (VpIsPosInf(a)) {
+                fprintf(fp, SZ_INF);
+                nc += 8;
+            }
+            else if (VpIsNegInf(a)) {
+                fprintf(fp, SZ_NINF);
+                nc += 9;
+            }
+            else if (!VpIsZero(a)) {
+                if (BIGDECIMAL_NEGATIVE_P(a)) {
+                    fprintf(fp, "-");
+                    ++nc;
+                }
+                nc += fprintf(fp, "0.");
+                switch (*(cntl_chr + j + 1)) {
+                  default:
+                    break;
 
-		case '0': case 'z':
-		    ZeroSup = 0;
-		    ++j;
-		    sep = cntl_chr[j] == 'z' ? BIGDECIMAL_COMPONENT_FIGURES : 10;
-		    break;
-		}
-		for (i = 0; i < a->Prec; ++i) {
-		    m = BASE1;
-		    e = a->frac[i];
-		    while (m) {
-			nn = e / m;
-			if (!ZeroSup || nn) {
-			    nc += fprintf(fp, "%lu", (unsigned long)nn);    /* The leading zero(s) */
-			    /* as 0.00xx will not */
-			    /* be printed. */
-			    ++nd;
-			    ZeroSup = 0;    /* Set to print succeeding zeros */
-			}
-			if (nd >= sep) {    /* print ' ' after every 10 digits */
-			    nd = 0;
-			    nc += fprintf(fp, " ");
-			}
-			e = e - nn * m;
-			m /= 10;
-		    }
-		}
-		nc += fprintf(fp, "E%"PRIdSIZE, VpExponent10(a));
-		nc += fprintf(fp, " (%"PRIdVALUE", %lu, %lu)", a->exponent, a->Prec, a->MaxPrec);
-	    }
-	    else {
-		nc += fprintf(fp, "0.0");
-	    }
-	}
-	else {
-	    ++nc;
-	    if (*(cntl_chr + j) == '\\') {
-		switch (*(cntl_chr + j + 1)) {
-		  case 'n':
-		    fprintf(fp, "\n");
-		    ++j;
-		    break;
-		  case 't':
-		    fprintf(fp, "\t");
-		    ++j;
-		    break;
-		  case 'b':
-		    fprintf(fp, "\n");
-		    ++j;
-		    break;
-		  default:
-		    fprintf(fp, "%c", *(cntl_chr + j));
-		    break;
-		}
-	    }
-	    else {
-		fprintf(fp, "%c", *(cntl_chr + j));
-		if (*(cntl_chr + j) == '%') ++j;
-	    }
-	}
-	j++;
+                  case '0': case 'z':
+                    ZeroSup = 0;
+                    ++j;
+                    sep = cntl_chr[j] == 'z' ? BIGDECIMAL_COMPONENT_FIGURES : 10;
+                    break;
+                }
+                for (i = 0; i < a->Prec; ++i) {
+                    m = BASE1;
+                    e = a->frac[i];
+                    while (m) {
+                        nn = e / m;
+                        if (!ZeroSup || nn) {
+                            nc += fprintf(fp, "%lu", (unsigned long)nn);    /* The leading zero(s) */
+                            /* as 0.00xx will not */
+                            /* be printed. */
+                            ++nd;
+                            ZeroSup = 0;    /* Set to print succeeding zeros */
+                        }
+                        if (nd >= sep) {    /* print ' ' after every 10 digits */
+                            nd = 0;
+                            nc += fprintf(fp, " ");
+                        }
+                        e = e - nn * m;
+                        m /= 10;
+                    }
+                }
+                nc += fprintf(fp, "E%"PRIdSIZE, VpExponent10(a));
+                nc += fprintf(fp, " (%"PRIdVALUE", %lu, %lu)", a->exponent, a->Prec, a->MaxPrec);
+            }
+            else {
+                nc += fprintf(fp, "0.0");
+            }
+        }
+        else {
+            ++nc;
+            if (*(cntl_chr + j) == '\\') {
+                switch (*(cntl_chr + j + 1)) {
+                  case 'n':
+                    fprintf(fp, "\n");
+                    ++j;
+                    break;
+                  case 't':
+                    fprintf(fp, "\t");
+                    ++j;
+                    break;
+                  case 'b':
+                    fprintf(fp, "\n");
+                    ++j;
+                    break;
+                  default:
+                    fprintf(fp, "%c", *(cntl_chr + j));
+                    break;
+                }
+            }
+            else {
+                fprintf(fp, "%c", *(cntl_chr + j));
+                if (*(cntl_chr + j) == '%') ++j;
+            }
+        }
+        j++;
     }
 
     return (int)nc;
 }
-#endif
 
 static void
 VpFormatSt(char *psz, size_t fFmt)
@@ -6381,188 +6534,254 @@ VpExponent10(Real *a)
 }
 
 VP_EXPORT void
-VpSzMantissa(Real *a,char *psz)
+VpSzMantissa(Real *a, char *buf, size_t buflen)
 {
     size_t i, n, ZeroSup;
     DECDIG_DBL m, e, nn;
 
     if (VpIsNaN(a)) {
-	sprintf(psz, SZ_NaN);
-	return;
+        snprintf(buf, buflen, SZ_NaN);
+        return;
     }
     if (VpIsPosInf(a)) {
-	sprintf(psz, SZ_INF);
+	snprintf(buf, buflen, SZ_INF);
 	return;
     }
     if (VpIsNegInf(a)) {
-	sprintf(psz, SZ_NINF);
+	snprintf(buf, buflen, SZ_NINF);
 	return;
     }
 
     ZeroSup = 1;        /* Flag not to print the leading zeros as 0.00xxxxEnn */
     if (!VpIsZero(a)) {
-	if (BIGDECIMAL_NEGATIVE_P(a)) *psz++ = '-';
-	n = a->Prec;
-	for (i = 0; i < n; ++i) {
-	    m = BASE1;
-	    e = a->frac[i];
-	    while (m) {
-		nn = e / m;
-		if (!ZeroSup || nn) {
-		    sprintf(psz, "%lu", (unsigned long)nn); /* The leading zero(s) */
-		    psz += strlen(psz);
-		    /* as 0.00xx will be ignored. */
-		    ZeroSup = 0; /* Set to print succeeding zeros */
-		}
-		e = e - nn * m;
-		m /= 10;
-	    }
-	}
-	*psz = 0;
-	while (psz[-1] == '0') *(--psz) = 0;
+        if (BIGDECIMAL_NEGATIVE_P(a)) *buf++ = '-';
+        n = a->Prec;
+        for (i = 0; i < n; ++i) {
+            m = BASE1;
+            e = a->frac[i];
+            while (m) {
+                nn = e / m;
+                if (!ZeroSup || nn) {
+                    snprintf(buf, buflen, "%lu", (unsigned long)nn); /* The leading zero(s) */
+                    buf += strlen(buf);
+                    /* as 0.00xx will be ignored. */
+                    ZeroSup = 0; /* Set to print succeeding zeros */
+                }
+                e = e - nn * m;
+                m /= 10;
+            }
+        }
+        *buf = 0;
+        while (buf[-1] == '0') *(--buf) = 0;
     }
     else {
-	if (VpIsPosZero(a)) sprintf(psz, "0");
-	else                sprintf(psz, "-0");
+	if (VpIsPosZero(a)) snprintf(buf, buflen, "0");
+	else                snprintf(buf, buflen, "-0");
     }
 }
 
 VP_EXPORT int
-VpToSpecialString(Real *a,char *psz,int fPlus)
+VpToSpecialString(Real *a, char *buf, size_t buflen, int fPlus)
 /* fPlus = 0: default, 1: set ' ' before digits, 2: set '+' before digits. */
 {
     if (VpIsNaN(a)) {
-	sprintf(psz,SZ_NaN);
-	return 1;
+        snprintf(buf, buflen, SZ_NaN);
+        return 1;
     }
 
     if (VpIsPosInf(a)) {
-	if (fPlus == 1) {
-	    *psz++ = ' ';
-	}
-	else if (fPlus == 2) {
-	    *psz++ = '+';
-	}
-	sprintf(psz, SZ_INF);
-	return 1;
+        if (fPlus == 1) {
+            *buf++ = ' ';
+        }
+        else if (fPlus == 2) {
+            *buf++ = '+';
+        }
+        snprintf(buf, buflen, SZ_INF);
+        return 1;
     }
     if (VpIsNegInf(a)) {
-	sprintf(psz, SZ_NINF);
-	return 1;
+        snprintf(buf, buflen, SZ_NINF);
+        return 1;
     }
     if (VpIsZero(a)) {
-	if (VpIsPosZero(a)) {
-	    if (fPlus == 1)      sprintf(psz, " 0.0");
-	    else if (fPlus == 2) sprintf(psz, "+0.0");
-	    else                 sprintf(psz,  "0.0");
-	}
-	else                     sprintf(psz, "-0.0");
-	return 1;
+        if (VpIsPosZero(a)) {
+            if (fPlus == 1)      snprintf(buf, buflen, " 0.0");
+            else if (fPlus == 2) snprintf(buf, buflen, "+0.0");
+            else                 snprintf(buf, buflen,  "0.0");
+        }
+        else                     snprintf(buf, buflen, "-0.0");
+        return 1;
     }
     return 0;
 }
 
 VP_EXPORT void
-VpToString(Real *a, char *psz, size_t fFmt, int fPlus)
+VpToString(Real *a, char *buf, size_t buflen, size_t fFmt, int fPlus)
 /* fPlus = 0: default, 1: set ' ' before digits, 2: set '+' before digits. */
 {
     size_t i, n, ZeroSup;
     DECDIG shift, m, e, nn;
-    char *pszSav = psz;
+    char *p = buf;
+    size_t plen = buflen;
     ssize_t ex;
 
-    if (VpToSpecialString(a, psz, fPlus)) return;
+    if (VpToSpecialString(a, buf, buflen, fPlus)) return;
 
     ZeroSup = 1;    /* Flag not to print the leading zeros as 0.00xxxxEnn */
 
-    if (BIGDECIMAL_NEGATIVE_P(a)) *psz++ = '-';
-    else if (fPlus == 1)  *psz++ = ' ';
-    else if (fPlus == 2)  *psz++ = '+';
+#define ADVANCE(n) do { \
+    if (plen < n) goto overflow; \
+    p += n; \
+    plen -= n; \
+} while (0)
+
+    if (BIGDECIMAL_NEGATIVE_P(a)) {
+        *p = '-';
+        ADVANCE(1);
+    }
+    else if (fPlus == 1) {
+        *p = ' ';
+        ADVANCE(1);
+    }
+    else if (fPlus == 2) {
+        *p = '+';
+        ADVANCE(1);
+    }
+
+    *p = '0'; ADVANCE(1);
+    *p = '.'; ADVANCE(1);
 
-    *psz++ = '0';
-    *psz++ = '.';
     n = a->Prec;
     for (i = 0; i < n; ++i) {
-	m = BASE1;
-	e = a->frac[i];
-	while (m) {
-	    nn = e / m;
-	    if (!ZeroSup || nn) {
-		sprintf(psz, "%lu", (unsigned long)nn);    /* The reading zero(s) */
-		psz += strlen(psz);
-		/* as 0.00xx will be ignored. */
-		ZeroSup = 0;    /* Set to print succeeding zeros */
-	    }
-	    e = e - nn * m;
-	    m /= 10;
-	}
+        m = BASE1;
+        e = a->frac[i];
+        while (m) {
+            nn = e / m;
+            if (!ZeroSup || nn) {
+                /* The reading zero(s) */
+                size_t n = (size_t)snprintf(p, plen, "%lu", (unsigned long)nn);
+                if (n > plen) goto overflow;
+                ADVANCE(n);
+                /* as 0.00xx will be ignored. */
+                ZeroSup = 0;    /* Set to print succeeding zeros */
+            }
+            e = e - nn * m;
+            m /= 10;
+        }
     }
+
     ex = a->exponent * (ssize_t)BASE_FIG;
     shift = BASE1;
     while (a->frac[0] / shift == 0) {
-	--ex;
-	shift /= 10;
+        --ex;
+        shift /= 10;
     }
-    while (psz[-1] == '0') {
-	*(--psz) = 0;
+    while (p - 1 > buf && p[-1] == '0') {
+        *(--p) = '\0';
+        ++plen;
     }
-    sprintf(psz, "e%"PRIdSIZE, ex);
-    if (fFmt) VpFormatSt(pszSav, fFmt);
+    snprintf(p, plen, "e%"PRIdSIZE, ex);
+    if (fFmt) VpFormatSt(buf, fFmt);
+
+  overflow:
+    return;
+#undef ADVANCE
 }
 
 VP_EXPORT void
-VpToFString(Real *a, char *psz, size_t fFmt, int fPlus)
+VpToFString(Real *a, char *buf, size_t buflen, size_t fFmt, int fPlus)
 /* fPlus = 0: default, 1: set ' ' before digits, 2: set '+' before digits. */
 {
     size_t i, n;
     DECDIG m, e, nn;
-    char *pszSav = psz;
+    char *p = buf;
+    size_t plen = buflen;
     ssize_t ex;
 
-    if (VpToSpecialString(a, psz, fPlus)) return;
+    if (VpToSpecialString(a, buf, buflen, fPlus)) return;
 
-    if (BIGDECIMAL_NEGATIVE_P(a)) *psz++ = '-';
-    else if (fPlus == 1)  *psz++ = ' ';
-    else if (fPlus == 2)  *psz++ = '+';
+#define ADVANCE(n) do { \
+    if (plen < n) goto overflow; \
+    p += n; \
+    plen -= n; \
+} while (0)
+
+
+    if (BIGDECIMAL_NEGATIVE_P(a)) {
+        *p = '-';
+        ADVANCE(1);
+    }
+    else if (fPlus == 1) {
+        *p = ' ';
+        ADVANCE(1);
+    }
+    else if (fPlus == 2) {
+        *p = '+';
+        ADVANCE(1);
+    }
 
     n  = a->Prec;
     ex = a->exponent;
     if (ex <= 0) {
-	*psz++ = '0';*psz++ = '.';
-	while (ex < 0) {
-	    for (i=0; i < BASE_FIG; ++i) *psz++ = '0';
-	    ++ex;
-	}
-	ex = -1;
+        *p = '0'; ADVANCE(1);
+        *p = '.'; ADVANCE(1);
+        while (ex < 0) {
+            for (i=0; i < BASE_FIG; ++i) {
+                *p = '0'; ADVANCE(1);
+            }
+            ++ex;
+        }
+        ex = -1;
     }
 
     for (i = 0; i < n; ++i) {
-	--ex;
-	if (i == 0 && ex >= 0) {
-	    sprintf(psz, "%lu", (unsigned long)a->frac[i]);
-	    psz += strlen(psz);
-	}
-	else {
-	    m = BASE1;
-	    e = a->frac[i];
-	    while (m) {
-		nn = e / m;
-		*psz++ = (char)(nn + '0');
-		e = e - nn * m;
-		m /= 10;
-	    }
-	}
-	if (ex == 0) *psz++ = '.';
+        --ex;
+        if (i == 0 && ex >= 0) {
+            size_t n = snprintf(p, plen, "%lu", (unsigned long)a->frac[i]);
+            if (n > plen) goto overflow;
+            ADVANCE(n);
+        }
+        else {
+            m = BASE1;
+            e = a->frac[i];
+            while (m) {
+                nn = e / m;
+                *p = (char)(nn + '0');
+                ADVANCE(1);
+                e = e - nn * m;
+                m /= 10;
+            }
+        }
+        if (ex == 0) {
+            *p = '.';
+            ADVANCE(1);
+        }
     }
     while (--ex>=0) {
-	m = BASE;
-	while (m /= 10) *psz++ = '0';
-	if (ex == 0)    *psz++ = '.';
+        m = BASE;
+        while (m /= 10) {
+            *p = '0';
+            ADVANCE(1);
+        }
+        if (ex == 0) {
+            *p = '.';
+            ADVANCE(1);
+        }
+    }
+
+    *p = '\0';
+    while (p - 1 > buf && p[-1] == '0') {
+        *(--p) = '\0';
+        ++plen;
+    }
+    if (p - 1 > buf && p[-1] == '.') {
+        snprintf(p, plen, "0");
     }
-    *psz = 0;
-    while (psz[-1] == '0') *(--psz) = 0;
-    if (psz[-1] == '.') sprintf(psz, "0");
-    if (fFmt) VpFormatSt(pszSav, fFmt);
+    if (fFmt) VpFormatSt(buf, fFmt);
+
+  overflow:
+    return;
+#undef ADVANCE
 }
 
 /*
@@ -6971,8 +7190,9 @@ VpSqrt(Real *y, Real *x)
     if (x->MaxPrec > (size_t)n) n = (ssize_t)x->MaxPrec;
 
     /* allocate temporally variables  */
-    f = VpAlloc(y->MaxPrec * (BASE_FIG + 2), "#1", 1, 1);
-    r = VpAlloc((n + n) * (BASE_FIG + 2), "#1", 1, 1);
+    /* TODO: reconsider MaxPrec of f and r */
+    f = NewOneNolimit(1, y->MaxPrec * (BASE_FIG + 2));
+    r = NewOneNolimit(1, (n + n) * (BASE_FIG + 2));
 
     nr = 0;
     y_prec = y->MaxPrec;
@@ -6997,16 +7217,21 @@ VpSqrt(Real *y, Real *x)
     f->MaxPrec = y->MaxPrec + 1;
     n = (SIGNED_VALUE)(y_prec * BASE_FIG);
     if (n < (SIGNED_VALUE)maxnr) n = (SIGNED_VALUE)maxnr;
+
+    /*
+     * Perform: y_{n+1} = (y_n - x/y_n) / 2
+     */
     do {
-	y->MaxPrec *= 2;
-	if (y->MaxPrec > y_prec) y->MaxPrec = y_prec;
-	f->MaxPrec = y->MaxPrec;
-	VpDivd(f, r, x, y);      /* f = x/y    */
-	VpAddSub(r, f, y, -1);   /* r = f - y  */
-	VpMult(f, VpPt5, r);     /* f = 0.5*r  */
-	if (VpIsZero(f))         goto converge;
-	VpAddSub(r, f, y, 1);    /* r = y + f  */
-	VpAsgn(y, r, 1);         /* y = r      */
+        y->MaxPrec *= 2;
+        if (y->MaxPrec > y_prec) y->MaxPrec = y_prec;
+        f->MaxPrec = y->MaxPrec;
+        VpDivd(f, r, x, y);        /* f = x/y    */
+        VpAddSub(r, f, y, -1);     /* r = f - y  */
+        VpMult(f, VpConstPt5, r);  /* f = 0.5*r  */
+        if (VpIsZero(f))
+            goto converge;
+        VpAddSub(r, f, y, 1);      /* r = y + f  */
+        VpAsgn(y, r, 1);           /* y = r      */
     } while (++nr < n);
 
 #ifdef BIGDECIMAL_DEBUG
@@ -7031,8 +7256,8 @@ converge:
     y->MaxPrec = y_prec;
 
 Exit:
-    VpFree(f);
-    VpFree(r);
+    rbd_free_struct(f);
+    rbd_free_struct(r);
     return 1;
 }
 
@@ -7423,9 +7648,10 @@ VpPowerByInt(Real *y, Real *x, SIGNED_VALUE n)
     }
 
     /* Allocate working variables  */
+    /* TODO: reconsider MaxPrec of w1 and w2 */
+    w1 = NewZeroNolimit(1, (y->MaxPrec + 2) * BASE_FIG);
+    w2 = NewZeroNolimit(1, (w1->MaxPrec * 2 + 1) * BASE_FIG);
 
-    w1 = VpAlloc((y->MaxPrec + 2) * BASE_FIG, "#0", 1, 1);
-    w2 = VpAlloc((w1->MaxPrec * 2 + 1) * BASE_FIG, "#0", 1, 1);
     /* calculation start */
 
     VpAsgn(y, x, 1);
@@ -7454,8 +7680,8 @@ Exit:
 	printf("  n=%"PRIdVALUE"\n", n);
     }
 #endif /* BIGDECIMAL_DEBUG */
-    VpFree(w2);
-    VpFree(w1);
+    rbd_free_struct(w2);
+    rbd_free_struct(w1);
     return 1;
 }
 
diff --git a/ext/bigdecimal/bigdecimal.gemspec b/ext/bigdecimal/bigdecimal.gemspec
index 2ed7d09373..d215757188 100644
--- a/ext/bigdecimal/bigdecimal.gemspec
+++ b/ext/bigdecimal/bigdecimal.gemspec
@@ -2,14 +2,14 @@
 
 Gem::Specification.new do |s|
   s.name          = "bigdecimal"
-  s.version       = "3.1.2"
+  s.version       = "3.1.3"
   s.authors       = ["Kenta Murata", "Zachary Scott", "Shigeo Kobayashi"]
   s.email         = ["mrkn@mrkn.jp"]
 
   s.summary       = "Arbitrary-precision decimal floating-point number library."
   s.description   = "This library provides arbitrary-precision decimal floating-point number class."
   s.homepage      = "https://github.com/ruby/bigdecimal"
-  s.license       = "Ruby"
+  s.licenses       = ["Ruby", "bsd-2-clause"]
 
   s.require_paths = %w[lib]
   s.extensions    = %w[ext/bigdecimal/extconf.rb]
diff --git a/ext/bigdecimal/bigdecimal.h b/ext/bigdecimal/bigdecimal.h
index bd1c46743e..54fed811fb 100644
--- a/ext/bigdecimal/bigdecimal.h
+++ b/ext/bigdecimal/bigdecimal.h
@@ -102,7 +102,7 @@ extern VALUE rb_cBigDecimal;
  */
 #define VP_EXPORT static
 
-/* Exception codes */
+/* Exception mode */
 #define VP_EXCEPTION_ALL        ((unsigned short)0x00FF)
 #define VP_EXCEPTION_INFINITY   ((unsigned short)0x0001)
 #define VP_EXCEPTION_NaN        ((unsigned short)0x0002)
@@ -115,18 +115,36 @@ extern VALUE rb_cBigDecimal;
 
 #define BIGDECIMAL_EXCEPTION_MODE_DEFAULT 0U
 
-/* Computation mode */
+/* This is used in BigDecimal#mode */
 #define VP_ROUND_MODE            ((unsigned short)0x0100)
-#define VP_ROUND_UP         1
-#define VP_ROUND_DOWN       2
-#define VP_ROUND_HALF_UP    3
-#define VP_ROUND_HALF_DOWN  4
-#define VP_ROUND_CEIL       5
-#define VP_ROUND_FLOOR      6
-#define VP_ROUND_HALF_EVEN  7
+
+/* Rounding mode */
+#define VP_ROUND_UP         RBD_ROUND_UP
+#define VP_ROUND_DOWN       RBD_ROUND_DOWN
+#define VP_ROUND_HALF_UP    RBD_ROUND_HALF_UP
+#define VP_ROUND_HALF_DOWN  RBD_ROUND_HALF_DOWN
+#define VP_ROUND_CEIL       RBD_ROUND_CEIL
+#define VP_ROUND_FLOOR      RBD_ROUND_FLOOR
+#define VP_ROUND_HALF_EVEN  RBD_ROUND_HALF_EVEN
+
+enum rbd_rounding_mode {
+    RBD_ROUND_UP          = 1,
+    RBD_ROUND_DOWN        = 2,
+    RBD_ROUND_HALF_UP     = 3,
+    RBD_ROUND_HALF_DOWN   = 4,
+    RBD_ROUND_CEIL        = 5,
+    RBD_ROUND_FLOOR       = 6,
+    RBD_ROUND_HALF_EVEN   = 7,
+
+    RBD_ROUND_DEFAULT  = RBD_ROUND_HALF_UP,
+    RBD_ROUND_TRUNCATE = RBD_ROUND_DOWN,
+    RBD_ROUND_BANKER   = RBD_ROUND_HALF_EVEN,
+    RBD_ROUND_CEILING  = RBD_ROUND_CEIL
+};
 
 #define BIGDECIMAL_ROUNDING_MODE_DEFAULT  VP_ROUND_HALF_UP
 
+/* Sign flag */
 #define VP_SIGN_NaN                0 /* NaN                      */
 #define VP_SIGN_POSITIVE_ZERO      1 /* Positive zero            */
 #define VP_SIGN_NEGATIVE_ZERO     -1 /* Negative zero            */
@@ -135,6 +153,7 @@ extern VALUE rb_cBigDecimal;
 #define VP_SIGN_POSITIVE_INFINITE  3 /* Positive infinite number */
 #define VP_SIGN_NEGATIVE_INFINITE -3 /* Negative infinite number */
 
+/* The size of fraction part array */
 #if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)
 #define	FLEXIBLE_ARRAY_SIZE /* */
 #elif defined(__GNUC__) && !defined(__STRICT_ANSI__)
@@ -205,9 +224,6 @@ VP_EXPORT int VpIsNegDoubleZero(double v);
 #endif
 VP_EXPORT size_t VpNumOfChars(Real *vp,const char *pszFmt);
 VP_EXPORT size_t VpInit(DECDIG BaseVal);
-VP_EXPORT void *VpMemAlloc(size_t mb);
-VP_EXPORT void *VpMemRealloc(void *ptr, size_t mb);
-VP_EXPORT void VpFree(Real *pv);
 VP_EXPORT Real *VpAlloc(size_t mx, const char *szVal, int strict_p, int exc);
 VP_EXPORT size_t VpAsgn(Real *c, Real *a, int isw);
 VP_EXPORT size_t VpAddSub(Real *c,Real *a,Real *b,int operation);
@@ -215,10 +231,10 @@ VP_EXPORT size_t VpMult(Real *c,Real *a,Real *b);
 VP_EXPORT size_t VpDivd(Real *c,Real *r,Real *a,Real *b);
 VP_EXPORT int VpComp(Real *a,Real *b);
 VP_EXPORT ssize_t VpExponent10(Real *a);
-VP_EXPORT void VpSzMantissa(Real *a,char *psz);
-VP_EXPORT int VpToSpecialString(Real *a,char *psz,int fPlus);
-VP_EXPORT void VpToString(Real *a, char *psz, size_t fFmt, int fPlus);
-VP_EXPORT void VpToFString(Real *a, char *psz, size_t fFmt, int fPlus);
+VP_EXPORT void VpSzMantissa(Real *a, char *buf, size_t bufsize);
+VP_EXPORT int VpToSpecialString(Real *a, char *buf, size_t bufsize, int fPlus);
+VP_EXPORT void VpToString(Real *a, char *buf, size_t bufsize, size_t fFmt, int fPlus);
+VP_EXPORT void VpToFString(Real *a, char *buf, size_t bufsize, size_t fFmt, int fPlus);
 VP_EXPORT int VpCtoV(Real *a, const char *int_chr, size_t ni, const char *frac, size_t nf, const char *exp_chr, size_t ne);
 VP_EXPORT int VpVtoD(double *d, SIGNED_VALUE *e, Real *m);
 VP_EXPORT void VpDtoV(Real *m,double d);
diff --git a/ext/bigdecimal/extconf.rb b/ext/bigdecimal/extconf.rb
index 9b0c55b21c..17e7905dd6 100644
--- a/ext/bigdecimal/extconf.rb
+++ b/ext/bigdecimal/extconf.rb
@@ -67,14 +67,10 @@ have_header("ruby/atomic.h")
 have_header("ruby/internal/has/builtin.h")
 have_header("ruby/internal/static_assert.h")
 
-have_type("struct RRational", "ruby.h")
 have_func("rb_rational_num", "ruby.h")
 have_func("rb_rational_den", "ruby.h")
-have_type("struct RComplex", "ruby.h")
 have_func("rb_complex_real", "ruby.h")
 have_func("rb_complex_imag", "ruby.h")
-have_func("rb_array_const_ptr", "ruby.h")
-have_func("rb_sym2str", "ruby.h")
 have_func("rb_opts_exception_p", "ruby.h")
 have_func("rb_category_warn", "ruby.h")
 have_const("RB_WARN_CATEGORY_DEPRECATED", "ruby.h")
diff --git a/ext/bigdecimal/lib/bigdecimal/jacobian.rb b/ext/bigdecimal/lib/bigdecimal/jacobian.rb
index 5e29304299..4448024c74 100644
--- a/ext/bigdecimal/lib/bigdecimal/jacobian.rb
+++ b/ext/bigdecimal/lib/bigdecimal/jacobian.rb
@@ -42,8 +42,8 @@ module Jacobian
   end
 
 
-  # Computes the derivative of f[i] at x[i].
-  # fx is the value of f at x.
+  # Computes the derivative of +f[i]+ at +x[i]+.
+  # +fx+ is the value of +f+ at +x+.
   def dfdxi(f,fx,x,i)
     nRetry = 0
     n = x.size
@@ -75,7 +75,7 @@ module Jacobian
     deriv
   end
 
-  # Computes the Jacobian of f at x. fx is the value of f at x.
+  # Computes the Jacobian of +f+ at +x+. +fx+ is the value of +f+ at +x+.
   def jacobian(f,fx,x)
     n = x.size
     dfdx = Array.new(n*n)
diff --git a/ext/bigdecimal/lib/bigdecimal/util.rb b/ext/bigdecimal/lib/bigdecimal/util.rb
index cb645d2a71..ad92f7cfe6 100644
--- a/ext/bigdecimal/lib/bigdecimal/util.rb
+++ b/ext/bigdecimal/lib/bigdecimal/util.rb
@@ -33,12 +33,16 @@ class Float < Numeric
   #
   # Returns the value of +float+ as a BigDecimal.
   # The +precision+ parameter is used to determine the number of
-  # significant digits for the result (the default is Float::DIG).
+  # significant digits for the result. When +precision+ is set to +0+,
+  # the number of digits to represent the float being converted is determined
+  # automatically.
+  # The default +precision+ is +0+.
   #
   #     require 'bigdecimal'
   #     require 'bigdecimal/util'
   #
   #     0.5.to_d         # => 0.5e0
+  #     1.234.to_d       # => 0.1234e1
   #     1.234.to_d(2)    # => 0.12e1
   #
   # See also BigDecimal::new.
diff --git a/ext/bigdecimal/missing.h b/ext/bigdecimal/missing.h
index 7969849158..325554b5f5 100644
--- a/ext/bigdecimal/missing.h
+++ b/ext/bigdecimal/missing.h
@@ -35,10 +35,10 @@ extern "C" {
 #endif /* RB_UNUSED_VAR */
 
 #if defined(_MSC_VER) && _MSC_VER >= 1310
-# define HAVE___ASSUME
+# define HAVE___ASSUME 1
 
 #elif defined(__INTEL_COMPILER) && __INTEL_COMPILER >= 1300
-# define HAVE___ASSUME
+# define HAVE___ASSUME 1
 #endif
 
 #ifndef UNREACHABLE
@@ -126,7 +126,7 @@ char *BigDecimal_dtoa(double d_, int mode, int ndigits, int *decpt, int *sign, c
 static inline VALUE
 rb_rational_num(VALUE rat)
 {
-#ifdef HAVE_TYPE_STRUCT_RRATIONAL
+#ifdef RRATIONAL
     return RRATIONAL(rat)->num;
 #else
     return rb_funcall(rat, rb_intern("numerator"), 0);
@@ -138,7 +138,7 @@ rb_rational_num(VALUE rat)
 static inline VALUE
 rb_rational_den(VALUE rat)
 {
-#ifdef HAVE_TYPE_STRUCT_RRATIONAL
+#ifdef RRATIONAL
     return RRATIONAL(rat)->den;
 #else
     return rb_funcall(rat, rb_intern("denominator"), 0);
@@ -152,7 +152,7 @@ rb_rational_den(VALUE rat)
 static inline VALUE
 rb_complex_real(VALUE cmp)
 {
-#ifdef HAVE_TYPE_STRUCT_RCOMPLEX
+#ifdef RCOMPLEX
   return RCOMPLEX(cmp)->real;
 #else
   return rb_funcall(cmp, rb_intern("real"), 0);
@@ -164,7 +164,7 @@ rb_complex_real(VALUE cmp)
 static inline VALUE
 rb_complex_imag(VALUE cmp)
 {
-# ifdef HAVE_TYPE_STRUCT_RCOMPLEX
+# ifdef RCOMPLEX
   return RCOMPLEX(cmp)->imag;
 # else
   return rb_funcall(cmp, rb_intern("imag"), 0);
@@ -172,45 +172,6 @@ rb_complex_imag(VALUE cmp)
 }
 #endif
 
-/* array */
-
-#ifndef FIX_CONST_VALUE_PTR
-# if defined(__fcc__) || defined(__fcc_version) || \
-    defined(__FCC__) || defined(__FCC_VERSION)
-/* workaround for old version of Fujitsu C Compiler (fcc) */
-#  define FIX_CONST_VALUE_PTR(x) ((const VALUE *)(x))
-# else
-#  define FIX_CONST_VALUE_PTR(x) (x)
-# endif
-#endif
-
-#ifndef HAVE_RB_ARRAY_CONST_PTR
-static inline const VALUE *
-rb_array_const_ptr(VALUE a)
-{
-    return FIX_CONST_VALUE_PTR((RBASIC(a)->flags & RARRAY_EMBED_FLAG) ?
-	RARRAY(a)->as.ary : RARRAY(a)->as.heap.ptr);
-}
-#endif
-
-#ifndef RARRAY_CONST_PTR
-# define RARRAY_CONST_PTR(a) rb_array_const_ptr(a)
-#endif
-
-#ifndef RARRAY_AREF
-# define RARRAY_AREF(a, i) (RARRAY_CONST_PTR(a)[i])
-#endif
-
-/* symbol */
-
-#ifndef HAVE_RB_SYM2STR
-static inline VALUE
-rb_sym2str(VALUE sym)
-{
-    return rb_id2str(SYM2ID(sym));
-}
-#endif
-
 /* st */
 
 #ifndef ST2FIX
diff --git a/ext/cgi/escape/escape.c b/ext/cgi/escape/escape.c
index f88b61478b..c5b76de596 100644
--- a/ext/cgi/escape/escape.c
+++ b/ext/cgi/escape/escape.c
@@ -37,7 +37,7 @@ escaped_length(VALUE str)
 {
     const long len = RSTRING_LEN(str);
     if (len >= LONG_MAX / HTML_ESCAPE_MAX_LEN) {
-	ruby_malloc_size_overflow(len, HTML_ESCAPE_MAX_LEN);
+        ruby_malloc_size_overflow(len, HTML_ESCAPE_MAX_LEN);
     }
     return len * HTML_ESCAPE_MAX_LEN;
 }
@@ -81,8 +81,8 @@ optimized_unescape_html(VALUE str)
     enum {UNICODE_MAX = 0x10ffff};
     rb_encoding *enc = rb_enc_get(str);
     unsigned long charlimit = (strcasecmp(rb_enc_name(enc), "UTF-8") == 0 ? UNICODE_MAX :
-			       strcasecmp(rb_enc_name(enc), "ISO-8859-1") == 0 ? 256 :
-			       128);
+                               strcasecmp(rb_enc_name(enc), "ISO-8859-1") == 0 ? 256 :
+                               128);
     long i, len, beg = 0;
     size_t clen, plen;
     int overflow;
@@ -94,89 +94,89 @@ optimized_unescape_html(VALUE str)
     cstr = RSTRING_PTR(str);
 
     for (i = 0; i < len; i++) {
-	unsigned long cc;
-	char c = cstr[i];
-	if (c != '&') continue;
-	plen = i - beg;
-	if (++i >= len) break;
-	c = (unsigned char)cstr[i];
+        unsigned long cc;
+        char c = cstr[i];
+        if (c != '&') continue;
+        plen = i - beg;
+        if (++i >= len) break;
+        c = (unsigned char)cstr[i];
 #define MATCH(s) (len - i >= (int)rb_strlen_lit(s) && \
-		  memcmp(&cstr[i], s, rb_strlen_lit(s)) == 0 && \
-		  (i += rb_strlen_lit(s) - 1, 1))
-	switch (c) {
-	  case 'a':
-	    ++i;
-	    if (MATCH("pos;")) {
-		c = '\'';
-	    }
-	    else if (MATCH("mp;")) {
-		c = '&';
-	    }
-	    else continue;
-	    break;
-	  case 'q':
-	    ++i;
-	    if (MATCH("uot;")) {
-		c = '"';
-	    }
-	    else continue;
-	    break;
-	  case 'g':
-	    ++i;
-	    if (MATCH("t;")) {
-		c = '>';
-	    }
-	    else continue;
-	    break;
-	  case 'l':
-	    ++i;
-	    if (MATCH("t;")) {
-		c = '<';
-	    }
-	    else continue;
-	    break;
-	  case '#':
-	    if (len - ++i >= 2 && ISDIGIT(cstr[i])) {
-		cc = ruby_scan_digits(&cstr[i], len-i, 10, &clen, &overflow);
-	    }
-	    else if ((cstr[i] == 'x' || cstr[i] == 'X') && len - ++i >= 2 && ISXDIGIT(cstr[i])) {
-		cc = ruby_scan_digits(&cstr[i], len-i, 16, &clen, &overflow);
-	    }
-	    else continue;
-	    i += clen;
-	    if (overflow || cc >= charlimit || cstr[i] != ';') continue;
-	    if (!dest) {
-		dest = rb_str_buf_new(len);
-	    }
-	    rb_str_cat(dest, cstr + beg, plen);
-	    if (charlimit > 256) {
-		rb_str_cat(dest, buf, rb_enc_mbcput((OnigCodePoint)cc, buf, enc));
-	    }
-	    else {
-		c = (unsigned char)cc;
-		rb_str_cat(dest, &c, 1);
-	    }
-	    beg = i + 1;
-	    continue;
-	  default:
-	    --i;
-	    continue;
-	}
-	if (!dest) {
-	    dest = rb_str_buf_new(len);
-	}
-	rb_str_cat(dest, cstr + beg, plen);
-	rb_str_cat(dest, &c, 1);
-	beg = i + 1;
+                  memcmp(&cstr[i], s, rb_strlen_lit(s)) == 0 && \
+                  (i += rb_strlen_lit(s) - 1, 1))
+        switch (c) {
+          case 'a':
+            ++i;
+            if (MATCH("pos;")) {
+                c = '\'';
+            }
+            else if (MATCH("mp;")) {
+                c = '&';
+            }
+            else continue;
+            break;
+          case 'q':
+            ++i;
+            if (MATCH("uot;")) {
+                c = '"';
+            }
+            else continue;
+            break;
+          case 'g':
+            ++i;
+            if (MATCH("t;")) {
+                c = '>';
+            }
+            else continue;
+            break;
+          case 'l':
+            ++i;
+            if (MATCH("t;")) {
+                c = '<';
+            }
+            else continue;
+            break;
+          case '#':
+            if (len - ++i >= 2 && ISDIGIT(cstr[i])) {
+                cc = ruby_scan_digits(&cstr[i], len-i, 10, &clen, &overflow);
+            }
+            else if ((cstr[i] == 'x' || cstr[i] == 'X') && len - ++i >= 2 && ISXDIGIT(cstr[i])) {
+                cc = ruby_scan_digits(&cstr[i], len-i, 16, &clen, &overflow);
+            }
+            else continue;
+            i += clen;
+            if (overflow || cc >= charlimit || cstr[i] != ';') continue;
+            if (!dest) {
+                dest = rb_str_buf_new(len);
+            }
+            rb_str_cat(dest, cstr + beg, plen);
+            if (charlimit > 256) {
+                rb_str_cat(dest, buf, rb_enc_mbcput((OnigCodePoint)cc, buf, enc));
+            }
+            else {
+                c = (unsigned char)cc;
+                rb_str_cat(dest, &c, 1);
+            }
+            beg = i + 1;
+            continue;
+          default:
+            --i;
+            continue;
+        }
+        if (!dest) {
+            dest = rb_str_buf_new(len);
+        }
+        rb_str_cat(dest, cstr + beg, plen);
+        rb_str_cat(dest, &c, 1);
+        beg = i + 1;
     }
 
     if (dest) {
-	rb_str_cat(dest, cstr + beg, len - beg);
-	preserve_original_state(str, dest);
-	return dest;
+        rb_str_cat(dest, cstr + beg, len - beg);
+        preserve_original_state(str, dest);
+        return dest;
     }
     else {
-	return rb_str_dup(str);
+        return rb_str_dup(str);
     }
 }
 
@@ -200,7 +200,7 @@ url_unreserved_char(unsigned char c)
 }
 
 static VALUE
-optimized_escape(VALUE str)
+optimized_escape(VALUE str, int plus_escape)
 {
     long i, len, beg = 0;
     VALUE dest = 0;
@@ -211,38 +211,38 @@ optimized_escape(VALUE str)
     cstr = RSTRING_PTR(str);
 
     for (i = 0; i < len; ++i) {
-	const unsigned char c = (unsigned char)cstr[i];
-	if (!url_unreserved_char(c)) {
-	    if (!dest) {
-		dest = rb_str_buf_new(len);
-	    }
-
-	    rb_str_cat(dest, cstr + beg, i - beg);
-	    beg = i + 1;
-
-	    if (c == ' ') {
-		rb_str_cat_cstr(dest, "+");
-	    }
-	    else {
-		buf[1] = upper_hexdigits[(c >> 4) & 0xf];
-		buf[2] = upper_hexdigits[c & 0xf];
-		rb_str_cat(dest, buf, 3);
-	    }
-	}
+        const unsigned char c = (unsigned char)cstr[i];
+        if (!url_unreserved_char(c)) {
+            if (!dest) {
+                dest = rb_str_buf_new(len);
+            }
+
+            rb_str_cat(dest, cstr + beg, i - beg);
+            beg = i + 1;
+
+            if (plus_escape && c == ' ') {
+                rb_str_cat_cstr(dest, "+");
+            }
+            else {
+                buf[1] = upper_hexdigits[(c >> 4) & 0xf];
+                buf[2] = upper_hexdigits[c & 0xf];
+                rb_str_cat(dest, buf, 3);
+            }
+        }
     }
 
     if (dest) {
-	rb_str_cat(dest, cstr + beg, len - beg);
-	preserve_original_state(str, dest);
-	return dest;
+        rb_str_cat(dest, cstr + beg, len - beg);
+        preserve_original_state(str, dest);
+        return dest;
     }
     else {
-	return rb_str_dup(str);
+        return rb_str_dup(str);
     }
 }
 
 static VALUE
-optimized_unescape(VALUE str, VALUE encoding)
+optimized_unescape(VALUE str, VALUE encoding, int unescape_plus)
 {
     long i, len, beg = 0;
     VALUE dest = 0;
@@ -254,52 +254,52 @@ optimized_unescape(VALUE str, VALUE encoding)
     cstr = RSTRING_PTR(str);
 
     for (i = 0; i < len; ++i) {
-	char buf[1];
-	const char c = cstr[i];
-	int clen = 0;
-	if (c == '%') {
-	    if (i + 3 > len) break;
-	    if (!ISXDIGIT(cstr[i+1])) continue;
-	    if (!ISXDIGIT(cstr[i+2])) continue;
-	    buf[0] = ((char_to_number(cstr[i+1]) << 4)
-		      | char_to_number(cstr[i+2]));
-	    clen = 2;
-	}
-	else if (c == '+') {
-	    buf[0] = ' ';
-	}
-	else {
-	    continue;
-	}
-
-	if (!dest) {
-	    dest = rb_str_buf_new(len);
-	}
-
-	rb_str_cat(dest, cstr + beg, i - beg);
-	i += clen;
-	beg = i + 1;
-
-	rb_str_cat(dest, buf, 1);
+        char buf[1];
+        const char c = cstr[i];
+        int clen = 0;
+        if (c == '%') {
+            if (i + 3 > len) break;
+            if (!ISXDIGIT(cstr[i+1])) continue;
+            if (!ISXDIGIT(cstr[i+2])) continue;
+            buf[0] = ((char_to_number(cstr[i+1]) << 4)
+                      | char_to_number(cstr[i+2]));
+            clen = 2;
+        }
+        else if (unescape_plus && c == '+') {
+            buf[0] = ' ';
+        }
+        else {
+            continue;
+        }
+
+        if (!dest) {
+            dest = rb_str_buf_new(len);
+        }
+
+        rb_str_cat(dest, cstr + beg, i - beg);
+        i += clen;
+        beg = i + 1;
+
+        rb_str_cat(dest, buf, 1);
     }
 
     if (dest) {
-	rb_str_cat(dest, cstr + beg, len - beg);
-	preserve_original_state(str, dest);
-	cr = ENC_CODERANGE_UNKNOWN;
+        rb_str_cat(dest, cstr + beg, len - beg);
+        preserve_original_state(str, dest);
+        cr = ENC_CODERANGE_UNKNOWN;
     }
     else {
-	dest = rb_str_dup(str);
-	cr = ENC_CODERANGE(str);
+        dest = rb_str_dup(str);
+        cr = ENC_CODERANGE(str);
     }
     origenc = rb_enc_get_index(str);
     if (origenc != encidx) {
-	rb_enc_associate_index(dest, encidx);
-	if (!ENC_CODERANGE_CLEAN_P(rb_enc_str_coderange(dest))) {
-	    rb_enc_associate_index(dest, origenc);
-	    if (cr != ENC_CODERANGE_UNKNOWN)
-		ENC_CODERANGE_SET(dest, cr);
-	}
+        rb_enc_associate_index(dest, encidx);
+        if (!ENC_CODERANGE_CLEAN_P(rb_enc_str_coderange(dest))) {
+            rb_enc_associate_index(dest, origenc);
+            if (cr != ENC_CODERANGE_UNKNOWN)
+                ENC_CODERANGE_SET(dest, cr);
+        }
     }
     return dest;
 }
@@ -317,10 +317,10 @@ cgiesc_escape_html(VALUE self, VALUE str)
     StringValue(str);
 
     if (rb_enc_str_asciicompat_p(str)) {
-	return optimized_escape_html(str);
+        return optimized_escape_html(str);
     }
     else {
-	return rb_call_super(1, &str);
+        return rb_call_super(1, &str);
     }
 }
 
@@ -337,10 +337,10 @@ cgiesc_unescape_html(VALUE self, VALUE str)
     StringValue(str);
 
     if (rb_enc_str_asciicompat_p(str)) {
-	return optimized_unescape_html(str);
+        return optimized_unescape_html(str);
     }
     else {
-	return rb_call_super(1, &str);
+        return rb_call_super(1, &str);
     }
 }
 
@@ -348,7 +348,7 @@ cgiesc_unescape_html(VALUE self, VALUE str)
  *  call-seq:
  *     CGI.escape(string) -> string
  *
- *  Returns URL-escaped string.
+ *  Returns URL-escaped string (+application/x-www-form-urlencoded+).
  *
  */
 static VALUE
@@ -357,10 +357,10 @@ cgiesc_escape(VALUE self, VALUE str)
     StringValue(str);
 
     if (rb_enc_str_asciicompat_p(str)) {
-	return optimized_escape(str);
+        return optimized_escape(str, 1);
     }
     else {
-	return rb_call_super(1, &str);
+        return rb_call_super(1, &str);
     }
 }
 
@@ -368,7 +368,7 @@ static VALUE
 accept_charset(int argc, VALUE *argv, VALUE self)
 {
     if (argc > 0)
-	return argv[0];
+        return argv[0];
     return rb_cvar_get(CLASS_OF(self), id_accept_charset);
 }
 
@@ -376,7 +376,7 @@ accept_charset(int argc, VALUE *argv, VALUE self)
  *  call-seq:
  *     CGI.unescape(string, encoding=@@accept_charset) -> string
  *
- *  Returns URL-unescaped string.
+ *  Returns URL-unescaped string (+application/x-www-form-urlencoded+).
  *
  */
 static VALUE
@@ -387,11 +387,54 @@ cgiesc_unescape(int argc, VALUE *argv, VALUE self)
     StringValue(str);
 
     if (rb_enc_str_asciicompat_p(str)) {
-	VALUE enc = accept_charset(argc-1, argv+1, self);
-	return optimized_unescape(str, enc);
+        VALUE enc = accept_charset(argc-1, argv+1, self);
+        return optimized_unescape(str, enc, 1);
+    }
+    else {
+        return rb_call_super(argc, argv);
+    }
+}
+
+/*
+ *  call-seq:
+ *     CGI.escapeURIComponent(string) -> string
+ *
+ *  Returns URL-escaped string following RFC 3986.
+ *
+ */
+static VALUE
+cgiesc_escape_uri_component(VALUE self, VALUE str)
+{
+    StringValue(str);
+
+    if (rb_enc_str_asciicompat_p(str)) {
+        return optimized_escape(str, 0);
+    }
+    else {
+        return rb_call_super(1, &str);
+    }
+}
+
+/*
+ *  call-seq:
+ *     CGI.unescapeURIComponent(string, encoding=@@accept_charset) -> string
+ *
+ *  Returns URL-unescaped string following RFC 3986.
+ *
+ */
+static VALUE
+cgiesc_unescape_uri_component(int argc, VALUE *argv, VALUE self)
+{
+    VALUE str = (rb_check_arity(argc, 1, 2), argv[0]);
+
+    StringValue(str);
+
+    if (rb_enc_str_asciicompat_p(str)) {
+        VALUE enc = accept_charset(argc-1, argv+1, self);
+        return optimized_unescape(str, enc, 0);
     }
     else {
-	return rb_call_super(argc, argv);
+        return rb_call_super(argc, argv);
     }
 }
 
@@ -414,6 +457,8 @@ InitVM_escape(void)
     rb_mUtil   = rb_define_module_under(rb_cCGI, "Util");
     rb_define_method(rb_mEscape, "escapeHTML", cgiesc_escape_html, 1);
     rb_define_method(rb_mEscape, "unescapeHTML", cgiesc_unescape_html, 1);
+    rb_define_method(rb_mEscape, "escapeURIComponent", cgiesc_escape_uri_component, 1);
+    rb_define_method(rb_mEscape, "unescapeURIComponent", cgiesc_unescape_uri_component, -1);
     rb_define_method(rb_mEscape, "escape", cgiesc_escape, 1);
     rb_define_method(rb_mEscape, "unescape", cgiesc_unescape, -1);
     rb_prepend_module(rb_mUtil, rb_mEscape);
diff --git a/ext/coverage/coverage.c b/ext/coverage/coverage.c
index 3dc2490d40..4578de54e4 100644
--- a/ext/coverage/coverage.c
+++ b/ext/coverage/coverage.c
@@ -24,11 +24,37 @@ static int current_mode;
 static VALUE me2counter = Qnil;
 
 /*
+ *  call-seq: Coverage.supported?(mode) -> true or false
+ *
+ *  Returns true if coverage measurement is supported for the given mode.
+ *
+ *  The mode should be one of the following symbols:
+ *  +:lines+, +:branches+, +:methods+, +:eval+.
+ *
+ *  Example:
+ *
+ *    Coverage.supported?(:lines)  #=> true
+ *    Coverage.supported?(:all)    #=> false
+ */
+static VALUE
+rb_coverage_supported(VALUE self, VALUE _mode)
+{
+    ID mode = RB_SYM2ID(_mode);
+
+    return RBOOL(
+        mode == rb_intern("lines") ||
+        mode == rb_intern("branches") ||
+        mode == rb_intern("methods") ||
+        mode == rb_intern("eval")
+    );
+}
+
+/*
  * call-seq:
- *    Coverage.setup                                              => nil
- *    Coverage.setup(:all)                                        => nil
- *    Coverage.setup(lines: bool, branches: bool, methods: bool)  => nil
- *    Coverage.setup(oneshot_lines: true)                         => nil
+ *    Coverage.setup                                                          => nil
+ *    Coverage.setup(:all)                                                    => nil
+ *    Coverage.setup(lines: bool, branches: bool, methods: bool, eval: bool)  => nil
+ *    Coverage.setup(oneshot_lines: true)                                     => nil
  *
  * Set up the coverage measurement.
  *
@@ -44,56 +70,57 @@ rb_coverage_setup(int argc, VALUE *argv, VALUE klass)
     int mode;
 
     if (current_state != IDLE) {
-	rb_raise(rb_eRuntimeError, "coverage measurement is already setup");
+        rb_raise(rb_eRuntimeError, "coverage measurement is already setup");
     }
 
     rb_scan_args(argc, argv, "01", &opt);
 
     if (argc == 0) {
-	mode = 0; /* compatible mode */
+        mode = 0; /* compatible mode */
     }
     else if (opt == ID2SYM(rb_intern("all"))) {
-	mode = COVERAGE_TARGET_LINES | COVERAGE_TARGET_BRANCHES | COVERAGE_TARGET_METHODS;
+        mode = COVERAGE_TARGET_LINES | COVERAGE_TARGET_BRANCHES | COVERAGE_TARGET_METHODS | COVERAGE_TARGET_EVAL;
     }
     else {
-	mode = 0;
-	opt = rb_convert_type(opt, T_HASH, "Hash", "to_hash");
-
-	if (RTEST(rb_hash_lookup(opt, ID2SYM(rb_intern("lines")))))
-	    mode |= COVERAGE_TARGET_LINES;
-	if (RTEST(rb_hash_lookup(opt, ID2SYM(rb_intern("branches")))))
-	    mode |= COVERAGE_TARGET_BRANCHES;
-	if (RTEST(rb_hash_lookup(opt, ID2SYM(rb_intern("methods")))))
-	    mode |= COVERAGE_TARGET_METHODS;
+        mode = 0;
+        opt = rb_convert_type(opt, T_HASH, "Hash", "to_hash");
+
+        if (RTEST(rb_hash_lookup(opt, ID2SYM(rb_intern("lines")))))
+            mode |= COVERAGE_TARGET_LINES;
+        if (RTEST(rb_hash_lookup(opt, ID2SYM(rb_intern("branches")))))
+            mode |= COVERAGE_TARGET_BRANCHES;
+        if (RTEST(rb_hash_lookup(opt, ID2SYM(rb_intern("methods")))))
+            mode |= COVERAGE_TARGET_METHODS;
         if (RTEST(rb_hash_lookup(opt, ID2SYM(rb_intern("oneshot_lines"))))) {
             if (mode & COVERAGE_TARGET_LINES)
                 rb_raise(rb_eRuntimeError, "cannot enable lines and oneshot_lines simultaneously");
             mode |= COVERAGE_TARGET_LINES;
             mode |= COVERAGE_TARGET_ONESHOT_LINES;
         }
+        if (RTEST(rb_hash_lookup(opt, ID2SYM(rb_intern("eval")))))
+            mode |= COVERAGE_TARGET_EVAL;
     }
 
     if (mode & COVERAGE_TARGET_METHODS) {
         me2counter = rb_ident_hash_new();
     }
     else {
-	me2counter = Qnil;
+        me2counter = Qnil;
     }
 
     coverages = rb_get_coverages();
     if (!RTEST(coverages)) {
-	coverages = rb_hash_new();
-	rb_obj_hide(coverages);
-	current_mode = mode;
-	if (mode == 0) mode = COVERAGE_TARGET_LINES;
-	rb_set_coverages(coverages, mode, me2counter);
+        coverages = rb_hash_new();
+        rb_obj_hide(coverages);
+        current_mode = mode;
+        if (mode == 0) mode = COVERAGE_TARGET_LINES;
+        rb_set_coverages(coverages, mode, me2counter);
         current_state = SUSPENDED;
     }
     else if (current_mode != mode) {
-	rb_raise(rb_eRuntimeError, "cannot change the measuring target during coverage measurement");
+        rb_raise(rb_eRuntimeError, "cannot change the measuring target during coverage measurement");
     }
 
-
     return Qnil;
 }
 
@@ -104,7 +131,7 @@ rb_coverage_setup(int argc, VALUE *argv, VALUE klass)
  * Start/resume the coverage measurement.
  *
  * Caveat: Currently, only process-global coverage measurement is supported.
- * You cannot measure per-thread covearge. If your process has multiple thread,
+ * You cannot measure per-thread coverage. If your process has multiple thread,
  * using Coverage.resume/suspend to capture code coverage executed from only
  * a limited code block, may yield misleading results.
  */
@@ -112,10 +139,10 @@ VALUE
 rb_coverage_resume(VALUE klass)
 {
     if (current_state == IDLE) {
-	rb_raise(rb_eRuntimeError, "coverage measurement is not set up yet");
+        rb_raise(rb_eRuntimeError, "coverage measurement is not set up yet");
     }
     if (current_state == RUNNING) {
-	rb_raise(rb_eRuntimeError, "coverage measurement is already running");
+        rb_raise(rb_eRuntimeError, "coverage measurement is already running");
     }
     rb_resume_coverages();
     current_state = RUNNING;
@@ -124,10 +151,10 @@ rb_coverage_resume(VALUE klass)
 
 /*
  * call-seq:
- *    Coverage.start                                              => nil
- *    Coverage.start(:all)                                        => nil
- *    Coverage.start(lines: bool, branches: bool, methods: bool)  => nil
- *    Coverage.start(oneshot_lines: true)                         => nil
+ *    Coverage.start                                                          => nil
+ *    Coverage.start(:all)                                                    => nil
+ *    Coverage.start(lines: bool, branches: bool, methods: bool, eval: bool)  => nil
+ *    Coverage.start(oneshot_lines: true)                                     => nil
  *
  * Enables the coverage measurement.
  * See the documentation of Coverage class in detail.
@@ -218,45 +245,45 @@ method_coverage_i(void *vstart, void *vend, size_t stride, void *data)
         void *poisoned = asan_poisoned_object_p(v);
         asan_unpoison_object(v, false);
 
-	if (RB_TYPE_P(v, T_IMEMO) && imemo_type(v) == imemo_ment) {
-	    const rb_method_entry_t *me = (rb_method_entry_t *) v;
-	    VALUE path, first_lineno, first_column, last_lineno, last_column;
-	    VALUE data[5], ncoverage, methods;
-	    VALUE methods_id = ID2SYM(rb_intern("methods"));
-	    VALUE klass;
-	    const rb_method_entry_t *me2 = rb_resolve_me_location(me, data);
-	    if (me != me2) continue;
-	    klass = me->owner;
-	    if (RB_TYPE_P(klass, T_ICLASS)) {
-		rb_bug("T_ICLASS");
-	    }
-	    path = data[0];
-	    first_lineno = data[1];
-	    first_column = data[2];
-	    last_lineno = data[3];
-	    last_column = data[4];
-	    if (FIX2LONG(first_lineno) <= 0) continue;
-	    ncoverage = rb_hash_aref(ncoverages, path);
-	    if (NIL_P(ncoverage)) continue;
-	    methods = rb_hash_aref(ncoverage, methods_id);
-
-	    {
-		VALUE method_id = ID2SYM(me->def->original_id);
-		VALUE rcount = rb_hash_aref(me2counter, (VALUE) me);
-		VALUE key = rb_ary_new_from_args(6, klass, method_id, first_lineno, first_column, last_lineno, last_column);
-		VALUE rcount2 = rb_hash_aref(methods, key);
-
-		if (NIL_P(rcount)) rcount = LONG2FIX(0);
-		if (NIL_P(rcount2)) rcount2 = LONG2FIX(0);
-		if (!POSFIXABLE(FIX2LONG(rcount) + FIX2LONG(rcount2))) {
-		    rcount = LONG2FIX(FIXNUM_MAX);
-		}
-		else {
-		    rcount = LONG2FIX(FIX2LONG(rcount) + FIX2LONG(rcount2));
-		}
-		rb_hash_aset(methods, key, rcount);
-	    }
-	}
+        if (RB_TYPE_P(v, T_IMEMO) && imemo_type(v) == imemo_ment) {
+            const rb_method_entry_t *me = (rb_method_entry_t *) v;
+            VALUE path, first_lineno, first_column, last_lineno, last_column;
+            VALUE data[5], ncoverage, methods;
+            VALUE methods_id = ID2SYM(rb_intern("methods"));
+            VALUE klass;
+            const rb_method_entry_t *me2 = rb_resolve_me_location(me, data);
+            if (me != me2) continue;
+            klass = me->owner;
+            if (RB_TYPE_P(klass, T_ICLASS)) {
+                rb_bug("T_ICLASS");
+            }
+            path = data[0];
+            first_lineno = data[1];
+            first_column = data[2];
+            last_lineno = data[3];
+            last_column = data[4];
+            if (FIX2LONG(first_lineno) <= 0) continue;
+            ncoverage = rb_hash_aref(ncoverages, path);
+            if (NIL_P(ncoverage)) continue;
+            methods = rb_hash_aref(ncoverage, methods_id);
+
+            {
+                VALUE method_id = ID2SYM(me->def->original_id);
+                VALUE rcount = rb_hash_aref(me2counter, (VALUE) me);
+                VALUE key = rb_ary_new_from_args(6, klass, method_id, first_lineno, first_column, last_lineno, last_column);
+                VALUE rcount2 = rb_hash_aref(methods, key);
+
+                if (NIL_P(rcount)) rcount = LONG2FIX(0);
+                if (NIL_P(rcount2)) rcount2 = LONG2FIX(0);
+                if (!POSFIXABLE(FIX2LONG(rcount) + FIX2LONG(rcount2))) {
+                    rcount = LONG2FIX(FIXNUM_MAX);
+                }
+                else {
+                    rcount = LONG2FIX(FIX2LONG(rcount) + FIX2LONG(rcount2));
+                }
+                rb_hash_aset(methods, key, rcount);
+            }
+        }
 
         if (poisoned) {
             asan_poison_object(v);
@@ -272,32 +299,32 @@ coverage_peek_result_i(st_data_t key, st_data_t val, st_data_t h)
     VALUE coverage = (VALUE)val;
     VALUE coverages = (VALUE)h;
     if (current_mode == 0) {
-	/* compatible mode */
-	VALUE lines = rb_ary_dup(RARRAY_AREF(coverage, COVERAGE_INDEX_LINES));
-	rb_ary_freeze(lines);
-	coverage = lines;
+        /* compatible mode */
+        VALUE lines = rb_ary_dup(RARRAY_AREF(coverage, COVERAGE_INDEX_LINES));
+        rb_ary_freeze(lines);
+        coverage = lines;
     }
     else {
-	VALUE h = rb_hash_new();
+        VALUE h = rb_hash_new();
 
-	if (current_mode & COVERAGE_TARGET_LINES) {
-	    VALUE lines = RARRAY_AREF(coverage, COVERAGE_INDEX_LINES);
+        if (current_mode & COVERAGE_TARGET_LINES) {
+            VALUE lines = RARRAY_AREF(coverage, COVERAGE_INDEX_LINES);
             const char *kw = (current_mode & COVERAGE_TARGET_ONESHOT_LINES) ? "oneshot_lines" : "lines";
-	    lines = rb_ary_dup(lines);
-	    rb_ary_freeze(lines);
+            lines = rb_ary_dup(lines);
+            rb_ary_freeze(lines);
             rb_hash_aset(h, ID2SYM(rb_intern(kw)), lines);
-	}
+        }
 
-	if (current_mode & COVERAGE_TARGET_BRANCHES) {
-	    VALUE branches = RARRAY_AREF(coverage, COVERAGE_INDEX_BRANCHES);
-	    rb_hash_aset(h, ID2SYM(rb_intern("branches")), branch_coverage(branches));
-	}
+        if (current_mode & COVERAGE_TARGET_BRANCHES) {
+            VALUE branches = RARRAY_AREF(coverage, COVERAGE_INDEX_BRANCHES);
+            rb_hash_aset(h, ID2SYM(rb_intern("branches")), branch_coverage(branches));
+        }
 
-	if (current_mode & COVERAGE_TARGET_METHODS) {
-	    rb_hash_aset(h, ID2SYM(rb_intern("methods")), rb_hash_new());
-	}
+        if (current_mode & COVERAGE_TARGET_METHODS) {
+            rb_hash_aset(h, ID2SYM(rb_intern("methods")), rb_hash_new());
+        }
 
-	coverage = h;
+        coverage = h;
     }
 
     rb_hash_aset(coverages, path, coverage);
@@ -322,13 +349,13 @@ rb_coverage_peek_result(VALUE klass)
     VALUE coverages = rb_get_coverages();
     VALUE ncoverages = rb_hash_new();
     if (!RTEST(coverages)) {
-	rb_raise(rb_eRuntimeError, "coverage measurement is not enabled");
+        rb_raise(rb_eRuntimeError, "coverage measurement is not enabled");
     }
     OBJ_WB_UNPROTECT(coverages);
     st_foreach(RHASH_TBL_RAW(coverages), coverage_peek_result_i, ncoverages);
 
     if (current_mode & COVERAGE_TARGET_METHODS) {
-	rb_objspace_each_objects(method_coverage_i, &ncoverages);
+        rb_objspace_each_objects(method_coverage_i, &ncoverages);
     }
 
     rb_hash_freeze(ncoverages);
@@ -354,7 +381,7 @@ VALUE
 rb_coverage_suspend(VALUE klass)
 {
     if (current_state != RUNNING) {
-	rb_raise(rb_eRuntimeError, "coverage measurement is not running");
+        rb_raise(rb_eRuntimeError, "coverage measurement is not running");
     }
     rb_suspend_coverages();
     current_state = SUSPENDED;
@@ -377,7 +404,7 @@ rb_coverage_result(int argc, VALUE *argv, VALUE klass)
     int stop = 1, clear = 1;
 
     if (current_state == IDLE) {
-	rb_raise(rb_eRuntimeError, "coverage measurement is not enabled");
+        rb_raise(rb_eRuntimeError, "coverage measurement is not enabled");
     }
 
     rb_scan_args(argc, argv, "01", &opt);
@@ -443,7 +470,7 @@ rb_coverage_running(VALUE klass)
  * This feature is experimental, so these APIs may be changed in future.
  *
  * Caveat: Currently, only process-global coverage measurement is supported.
- * You cannot measure per-thread covearge.
+ * You cannot measure per-thread coverage.
  *
  * = Usage
  *
@@ -589,6 +616,9 @@ void
 Init_coverage(void)
 {
     VALUE rb_mCoverage = rb_define_module("Coverage");
+
+    rb_define_singleton_method(rb_mCoverage, "supported?", rb_coverage_supported, 1);
+
     rb_define_module_function(rb_mCoverage, "setup", rb_coverage_setup, -1);
     rb_define_module_function(rb_mCoverage, "start", rb_coverage_start, -1);
     rb_define_module_function(rb_mCoverage, "resume", rb_coverage_resume, 0);
diff --git a/ext/coverage/depend b/ext/coverage/depend
index 7c6aa6c2d8..e7fab16484 100644
--- a/ext/coverage/depend
+++ b/ext/coverage/depend
@@ -165,10 +165,12 @@ coverage.o: $(top_srcdir)/ccan/check_type/check_type.h
 coverage.o: $(top_srcdir)/ccan/container_of/container_of.h
 coverage.o: $(top_srcdir)/ccan/list/list.h
 coverage.o: $(top_srcdir)/ccan/str/str.h
-coverage.o: $(top_srcdir)/darray.h
+coverage.o: $(top_srcdir)/constant.h
 coverage.o: $(top_srcdir)/gc.h
+coverage.o: $(top_srcdir)/id_table.h
 coverage.o: $(top_srcdir)/internal.h
 coverage.o: $(top_srcdir)/internal/array.h
+coverage.o: $(top_srcdir)/internal/basic_operators.h
 coverage.o: $(top_srcdir)/internal/compilers.h
 coverage.o: $(top_srcdir)/internal/gc.h
 coverage.o: $(top_srcdir)/internal/hash.h
@@ -177,12 +179,14 @@ coverage.o: $(top_srcdir)/internal/sanitizers.h
 coverage.o: $(top_srcdir)/internal/serial.h
 coverage.o: $(top_srcdir)/internal/static_assert.h
 coverage.o: $(top_srcdir)/internal/thread.h
+coverage.o: $(top_srcdir)/internal/variable.h
 coverage.o: $(top_srcdir)/internal/vm.h
 coverage.o: $(top_srcdir)/internal/warnings.h
 coverage.o: $(top_srcdir)/method.h
 coverage.o: $(top_srcdir)/node.h
 coverage.o: $(top_srcdir)/ruby_assert.h
 coverage.o: $(top_srcdir)/ruby_atomic.h
+coverage.o: $(top_srcdir)/shape.h
 coverage.o: $(top_srcdir)/thread_pthread.h
 coverage.o: $(top_srcdir)/vm_core.h
 coverage.o: $(top_srcdir)/vm_opts.h
diff --git a/ext/date/date.gemspec b/ext/date/date.gemspec
index cf07696976..660353ebc5 100644
--- a/ext/date/date.gemspec
+++ b/ext/date/date.gemspec
@@ -10,14 +10,22 @@ Gem::Specification.new do |s|
   s.summary = "A subclass of Object includes Comparable module for handling dates."
   s.description = "A subclass of Object includes Comparable module for handling dates."
 
-  s.require_path = %w{lib}
-  s.files = [
-    "lib/date.rb", "ext/date/date_core.c", "ext/date/date_parse.c", "ext/date/date_strftime.c",
-    "ext/date/date_strptime.c", "ext/date/date_tmx.h", "ext/date/extconf.rb", "ext/date/prereq.mk",
-    "ext/date/zonetab.h", "ext/date/zonetab.list"
-  ]
-  s.extensions = "ext/date/extconf.rb"
-  s.required_ruby_version = ">= 2.4.0"
+  if Gem::Platform === s.platform and s.platform =~ 'java' or RUBY_ENGINE == 'jruby'
+    s.platform = 'java'
+    # No files shipped, no require path, no-op for now on JRuby
+  else
+    s.require_path = %w{lib}
+
+    s.files = [
+      "README.md",
+      "lib/date.rb", "ext/date/date_core.c", "ext/date/date_parse.c", "ext/date/date_strftime.c",
+      "ext/date/date_strptime.c", "ext/date/date_tmx.h", "ext/date/extconf.rb", "ext/date/prereq.mk",
+      "ext/date/zonetab.h", "ext/date/zonetab.list"
+    ]
+    s.extensions = "ext/date/extconf.rb"
+  end
+
+  s.required_ruby_version = ">= 2.6.0"
 
   s.authors = ["Tadayoshi Funaba"]
   s.email = [nil]
diff --git a/ext/date/date_core.c b/ext/date/date_core.c
index c7b4459c89..21367c0ddf 100644
--- a/ext/date/date_core.c
+++ b/ext/date/date_core.c
@@ -27,6 +27,10 @@ static VALUE eDateError;
 static VALUE half_days_in_day, day_in_nanoseconds;
 static double positive_inf, negative_inf;
 
+// used by deconstruct_keys
+static VALUE sym_year, sym_month, sym_day, sym_yday, sym_wday;
+static VALUE sym_hour, sym_min, sym_sec, sym_sec_fraction, sym_zone;
+
 #define f_boolcast(x) ((x) ? Qtrue : Qfalse)
 
 #define f_abs(x) rb_funcall(x, rb_intern("abs"), 0)
@@ -60,7 +64,8 @@ static VALUE datetime_initialize(int argc, VALUE *argv, VALUE self);
 
 #define RETURN_FALSE_UNLESS_NUMERIC(obj) if(!RTEST(rb_obj_is_kind_of((obj), rb_cNumeric))) return Qfalse
 inline static void
-check_numeric(VALUE obj, const char* field) {
+check_numeric(VALUE obj, const char* field)
+{
     if(!RTEST(rb_obj_is_kind_of(obj, rb_cNumeric))) {
         rb_raise(rb_eTypeError, "invalid %s (not numeric)", field);
     }
@@ -465,6 +470,7 @@ c_find_ldoy(int y, double sg, int *rjd, int *ns)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static int
 c_find_fdom(int y, int m, double sg, int *rjd, int *ns)
 {
@@ -621,6 +627,7 @@ c_jd_to_weeknum(int jd, int f, double sg, int *ry, int *rw, int *rd)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static void
 c_nth_kday_to_jd(int y, int m, int n, int k, double sg, int *rjd, int *ns)
 {
@@ -646,6 +653,7 @@ c_jd_to_wday(int jd)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static void
 c_jd_to_nth_kday(int jd, double sg, int *ry, int *rm, int *rn, int *rk)
 {
@@ -758,6 +766,8 @@ c_valid_civil_p(int y, int m, int d, double sg,
 
     if (m < 0)
 	m += 13;
+    if (m < 1 || m > 12)
+	return 0;
     if (d < 0) {
 	if (!c_find_ldom(y, m, sg, rjd, ns))
 	    return 0;
@@ -822,6 +832,7 @@ c_valid_weeknum_p(int y, int w, int d, int f, double sg,
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static int
 c_valid_nth_kday_p(int y, int m, int n, int k, double sg,
 		   int *rm, int *rn, int *rk, int *rjd, int *ns)
@@ -963,6 +974,7 @@ ns_to_day(VALUE n)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 ms_to_sec(VALUE m)
 {
@@ -981,6 +993,7 @@ ns_to_sec(VALUE n)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 inline static VALUE
 ins_to_day(int n)
 {
@@ -1016,6 +1029,7 @@ day_to_sec(VALUE d)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 day_to_ns(VALUE d)
 {
@@ -1040,6 +1054,7 @@ sec_to_ns(VALUE s)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 isec_to_ns(int s)
 {
@@ -1066,6 +1081,7 @@ div_df(VALUE d, VALUE *f)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 div_sf(VALUE s, VALUE *f)
 {
@@ -1500,6 +1516,7 @@ m_df(union DateData *x)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 m_df_in_day(union DateData *x)
 {
@@ -1997,6 +2014,7 @@ expect_numeric(VALUE x)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static void
 civil_to_jd(VALUE y, int m, int d, double sg,
 	    VALUE *nth, int *ry,
@@ -2309,6 +2327,7 @@ valid_weeknum_p(VALUE y, int w, int d, int f, double sg,
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static int
 valid_nth_kday_p(VALUE y, int m, int n, int k, double sg,
 		 VALUE *nth, int *ry,
@@ -2446,6 +2465,7 @@ valid_jd_sub(int argc, VALUE *argv, VALUE klass, int need_jd)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 date_s__valid_jd_p(int argc, VALUE *argv, VALUE klass)
 {
@@ -2466,13 +2486,16 @@ date_s__valid_jd_p(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date.valid_jd?(jd[, start=Date::ITALY])  ->  bool
+ *   Date.valid_jd?(jd, start = Date::ITALY) -> true
  *
- * Just returns true.  It's nonsense, but is for symmetry.
+ * Implemented for compatibility;
+ * returns +true+ unless +jd+ is invalid (i.e., not a Numeric).
  *
- *    Date.valid_jd?(2451944)		#=> true
+ *   Date.valid_jd?(2451944) # => true
  *
- * See also ::jd.
+ * See argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
+ *
+ * Related: Date.jd.
  */
 static VALUE
 date_s_valid_jd_p(int argc, VALUE *argv, VALUE klass)
@@ -2532,6 +2555,7 @@ valid_civil_sub(int argc, VALUE *argv, VALUE klass, int need_jd)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 date_s__valid_civil_p(int argc, VALUE *argv, VALUE klass)
 {
@@ -2554,18 +2578,20 @@ date_s__valid_civil_p(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date.valid_civil?(year, month, mday[, start=Date::ITALY])  ->  bool
- *    Date.valid_date?(year, month, mday[, start=Date::ITALY])   ->  bool
+ *   Date.valid_civil?(year, month, mday, start = Date::ITALY) -> true or false
+ *
+ * Returns +true+ if the arguments define a valid ordinal date,
+ * +false+ otherwise:
  *
- * Returns true if the given calendar date is valid, and false if not.
- * Valid in this context is whether the arguments passed to this
- * method would be accepted by ::new.
+ *   Date.valid_date?(2001, 2, 3)  # => true
+ *   Date.valid_date?(2001, 2, 29) # => false
+ *   Date.valid_date?(2001, 2, -1) # => true
  *
- *    Date.valid_date?(2001,2,3)	#=> true
- *    Date.valid_date?(2001,2,29)	#=> false
- *    Date.valid_date?(2001,2,-1)	#=> true
+ * See argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
  *
- * See also ::jd and ::civil.
+ * Date.valid_date? is an alias for Date.valid_civil?.
+ *
+ * Related: Date.jd, Date.new.
  */
 static VALUE
 date_s_valid_civil_p(int argc, VALUE *argv, VALUE klass)
@@ -2621,6 +2647,7 @@ valid_ordinal_sub(int argc, VALUE *argv, VALUE klass, int need_jd)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 date_s__valid_ordinal_p(int argc, VALUE *argv, VALUE klass)
 {
@@ -2642,14 +2669,17 @@ date_s__valid_ordinal_p(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date.valid_ordinal?(year, yday[, start=Date::ITALY])  ->  bool
+ *   Date.valid_ordinal?(year, yday, start = Date::ITALY) -> true or false
  *
- * Returns true if the given ordinal date is valid, and false if not.
+ * Returns +true+ if the arguments define a valid ordinal date,
+ * +false+ otherwise:
  *
- *    Date.valid_ordinal?(2001,34)	#=> true
- *    Date.valid_ordinal?(2001,366)	#=> false
+ *   Date.valid_ordinal?(2001, 34)  # => true
+ *   Date.valid_ordinal?(2001, 366) # => false
  *
- * See also ::jd and ::ordinal.
+ * See argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
+ *
+ * Related: Date.jd, Date.ordinal.
  */
 static VALUE
 date_s_valid_ordinal_p(int argc, VALUE *argv, VALUE klass)
@@ -2704,6 +2734,7 @@ valid_commercial_sub(int argc, VALUE *argv, VALUE klass, int need_jd)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 date_s__valid_commercial_p(int argc, VALUE *argv, VALUE klass)
 {
@@ -2726,14 +2757,19 @@ date_s__valid_commercial_p(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date.valid_commercial?(cwyear, cweek, cwday[, start=Date::ITALY])  ->  bool
+ *   Date.valid_commercial?(cwyear, cweek, cwday, start = Date::ITALY) -> true or false
+ *
+ * Returns +true+ if the arguments define a valid commercial date,
+ * +false+ otherwise:
  *
- * Returns true if the given week date is valid, and false if not.
+ *   Date.valid_commercial?(2001, 5, 6) # => true
+ *   Date.valid_commercial?(2001, 5, 8) # => false
  *
- *    Date.valid_commercial?(2001,5,6)	#=> true
- *    Date.valid_commercial?(2001,5,8)	#=> false
+ * See Date.commercial.
  *
- * See also ::jd and ::commercial.
+ * See argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
+ *
+ * Related: Date.jd, Date.commercial.
  */
 static VALUE
 date_s_valid_commercial_p(int argc, VALUE *argv, VALUE klass)
@@ -2760,6 +2796,7 @@ date_s_valid_commercial_p(int argc, VALUE *argv, VALUE klass)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 valid_weeknum_sub(int argc, VALUE *argv, VALUE klass, int need_jd)
 {
@@ -2791,6 +2828,7 @@ valid_weeknum_sub(int argc, VALUE *argv, VALUE klass, int need_jd)
     }
 }
 
+/* :nodoc: */
 static VALUE
 date_s__valid_weeknum_p(int argc, VALUE *argv, VALUE klass)
 {
@@ -2811,6 +2849,7 @@ date_s__valid_weeknum_p(int argc, VALUE *argv, VALUE klass)
     return valid_weeknum_sub(5, argv2, klass, 1);
 }
 
+/* :nodoc: */
 static VALUE
 date_s_valid_weeknum_p(int argc, VALUE *argv, VALUE klass)
 {
@@ -2862,6 +2901,7 @@ valid_nth_kday_sub(int argc, VALUE *argv, VALUE klass, int need_jd)
     }
 }
 
+/* :nodoc: */
 static VALUE
 date_s__valid_nth_kday_p(int argc, VALUE *argv, VALUE klass)
 {
@@ -2882,6 +2922,7 @@ date_s__valid_nth_kday_p(int argc, VALUE *argv, VALUE klass)
     return valid_nth_kday_sub(5, argv2, klass, 1);
 }
 
+/* :nodoc: */
 static VALUE
 date_s_valid_nth_kday_p(int argc, VALUE *argv, VALUE klass)
 {
@@ -2904,6 +2945,7 @@ date_s_valid_nth_kday_p(int argc, VALUE *argv, VALUE klass)
     return Qtrue;
 }
 
+/* :nodoc: */
 static VALUE
 date_s_zone_to_diff(VALUE klass, VALUE str)
 {
@@ -2913,13 +2955,15 @@ date_s_zone_to_diff(VALUE klass, VALUE str)
 
 /*
  * call-seq:
- *    Date.julian_leap?(year)  ->  bool
+ *   Date.julian_leap?(year) -> true or false
+ *
+ * Returns +true+ if the given year is a leap year
+ * in the {proleptic Julian calendar}[https://en.wikipedia.org/wiki/Proleptic_Julian_calendar], +false+ otherwise:
  *
- * Returns true if the given year is a leap year of the proleptic
- * Julian calendar.
+ *   Date.julian_leap?(1900) # => true
+ *   Date.julian_leap?(1901) # => false
  *
- *    Date.julian_leap?(1900)		#=> true
- *    Date.julian_leap?(1901)		#=> false
+ * Related: Date.gregorian_leap?.
  */
 static VALUE
 date_s_julian_leap_p(VALUE klass, VALUE y)
@@ -2934,14 +2978,17 @@ date_s_julian_leap_p(VALUE klass, VALUE y)
 
 /*
  * call-seq:
- *    Date.gregorian_leap?(year)  ->  bool
- *    Date.leap?(year)            ->  bool
+ *   Date.gregorian_leap?(year) -> true or false
  *
- * Returns true if the given year is a leap year of the proleptic
- * Gregorian calendar.
+ * Returns +true+ if the given year is a leap year
+ * in the {proleptic Gregorian calendar}[https://en.wikipedia.org/wiki/Proleptic_Gregorian_calendar], +false+ otherwise:
  *
- *    Date.gregorian_leap?(1900)	#=> false
- *    Date.gregorian_leap?(2000)	#=> true
+ *   Date.gregorian_leap?(2000) # => true
+ *   Date.gregorian_leap?(2001) # => false
+ *
+ * Date.leap? is an alias for Date.gregorian_leap?.
+ *
+ * Related: Date.julian_leap?.
  */
 static VALUE
 date_s_gregorian_leap_p(VALUE klass, VALUE y)
@@ -3094,6 +3141,7 @@ old_to_new(VALUE ajd, VALUE of, VALUE sg,
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 date_s_new_bang(int argc, VALUE *argv, VALUE klass)
 {
@@ -3281,16 +3329,29 @@ static VALUE d_lite_plus(VALUE, VALUE);
 
 /*
  * call-seq:
- *    Date.jd([jd=0[, start=Date::ITALY]])  ->  date
+ *   Date.jd(jd = 0, start = Date::ITALY) -> date
+ *
+ * Returns a new \Date object formed from the arguments:
+ *
+ *   Date.jd(2451944).to_s # => "2001-02-03"
+ *   Date.jd(2451945).to_s # => "2001-02-04"
+ *   Date.jd(0).to_s       # => "-4712-01-01"
  *
- * Creates a date object denoting the given chronological Julian day
- * number.
+ * The returned date is:
  *
- *    Date.jd(2451944)		#=> #<Date: 2001-02-03 ...>
- *    Date.jd(2451945)		#=> #<Date: 2001-02-04 ...>
- *    Date.jd(0)		#=> #<Date: -4712-01-01 ...>
+ * - Gregorian, if the argument is greater than or equal to +start+:
  *
- * See also ::new.
+ *     Date::ITALY                         # => 2299161
+ *     Date.jd(Date::ITALY).gregorian?     # => true
+ *     Date.jd(Date::ITALY + 1).gregorian? # => true
+ *
+ * - Julian, otherwise
+ *
+ *     Date.jd(Date::ITALY - 1).julian?    # => true
+ *
+ * See argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
+ *
+ * Related: Date.new.
  */
 static VALUE
 date_s_jd(int argc, VALUE *argv, VALUE klass)
@@ -3329,19 +3390,33 @@ date_s_jd(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date.ordinal([year=-4712[, yday=1[, start=Date::ITALY]]])  ->  date
+ *   Date.ordinal(year = -4712, yday = 1, start = Date::ITALY) -> date
+ *
+ * Returns a new \Date object formed fom the arguments.
  *
- * Creates a date object denoting the given ordinal date.
+ * With no arguments, returns the date for January 1, -4712:
  *
- * The day of year should be a negative or a positive number (as a
- * relative day from the end of year when negative).  It should not be
- * zero.
+ *   Date.ordinal.to_s # => "-4712-01-01"
  *
- *    Date.ordinal(2001)	#=> #<Date: 2001-01-01 ...>
- *    Date.ordinal(2001,34)	#=> #<Date: 2001-02-03 ...>
- *    Date.ordinal(2001,-1)	#=> #<Date: 2001-12-31 ...>
+ * With argument +year+, returns the date for January 1 of that year:
  *
- * See also ::jd and ::new.
+ *   Date.ordinal(2001).to_s  # => "2001-01-01"
+ *   Date.ordinal(-2001).to_s # => "-2001-01-01"
+ *
+ * With positive argument +yday+ == +n+,
+ * returns the date for the +nth+ day of the given year:
+ *
+ *   Date.ordinal(2001, 14).to_s # => "2001-01-14"
+ *
+ * With negative argument +yday+, counts backward from the end of the year:
+ *
+ *   Date.ordinal(2001, -14).to_s # => "2001-12-18"
+ *
+ * Raises an exception if +yday+ is zero or out of range.
+ *
+ * See argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
+ *
+ * Related: Date.jd, Date.new.
  */
 static VALUE
 date_s_ordinal(int argc, VALUE *argv, VALUE klass)
@@ -3389,29 +3464,7 @@ date_s_ordinal(int argc, VALUE *argv, VALUE klass)
 }
 
 /*
- * call-seq:
- *    Date.civil([year=-4712[, month=1[, mday=1[, start=Date::ITALY]]]])  ->  date
- *    Date.new([year=-4712[, month=1[, mday=1[, start=Date::ITALY]]]])    ->  date
- *
- * Creates a date object denoting the given calendar date.
- *
- * In this class, BCE years are counted astronomically.  Thus, the
- * year before the year 1 is the year zero, and the year preceding the
- * year zero is the year -1.  The month and the day of month should be
- * a negative or a positive number (as a relative month/day from the
- * end of year/month when negative).  They should not be zero.
- *
- * The last argument should be a Julian day number which denotes the
- * day of calendar reform.  Date::ITALY (2299161=1582-10-15),
- * Date::ENGLAND (2361222=1752-09-14), Date::GREGORIAN (the proleptic
- * Gregorian calendar) and Date::JULIAN (the proleptic Julian
- * calendar) can be specified as a day of calendar reform.
- *
- *    Date.new(2001)		#=> #<Date: 2001-01-01 ...>
- *    Date.new(2001,2,3)	#=> #<Date: 2001-02-03 ...>
- *    Date.new(2001,2,-1)	#=> #<Date: 2001-02-28 ...>
- *
- * See also ::jd.
+ * Same as Date.new.
  */
 static VALUE
 date_s_civil(int argc, VALUE *argv, VALUE klass)
@@ -3419,6 +3472,31 @@ date_s_civil(int argc, VALUE *argv, VALUE klass)
     return date_initialize(argc, argv, d_lite_s_alloc_simple(klass));
 }
 
+/*
+ * call-seq:
+ *   Date.new(year = -4712, month = 1, mday = 1, start = Date::ITALY) -> date
+ *
+ * Returns a new \Date object constructed from the given arguments:
+ *
+ *   Date.new(2022).to_s        # => "2022-01-01"
+ *   Date.new(2022, 2).to_s     # => "2022-02-01"
+ *   Date.new(2022, 2, 4).to_s  # => "2022-02-04"
+ *
+ * Argument +month+ should be in range (1..12) or range (-12..-1);
+ * when the argument is negative, counts backward from the end of the year:
+ *
+ *   Date.new(2022, -11, 4).to_s # => "2022-02-04"
+ *
+ * Argument +mday+ should be in range (1..n) or range (-n..-1)
+ * where +n+ is the number of days in the month;
+ * when the argument is negative, counts backward from the end of the month.
+ *
+ * See argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
+ *
+ * Date.civil is an alias for Date.new.
+ *
+ * Related: Date.jd.
+ */
 static VALUE
 date_initialize(int argc, VALUE *argv, VALUE self)
 {
@@ -3483,19 +3561,47 @@ date_initialize(int argc, VALUE *argv, VALUE self)
 
 /*
  * call-seq:
- *    Date.commercial([cwyear=-4712[, cweek=1[, cwday=1[, start=Date::ITALY]]]])  ->  date
+ *   Date.commercial(cwyear = -4712, cweek = 1, cwday = 1, start = Date::ITALY) -> date
+ *
+ * Returns a new \Date object constructed from the arguments.
+ *
+ * Argument +cwyear+ gives the year, and should be an integer.
+ *
+ * Argument +cweek+ gives the index of the week within the year,
+ * and should be in range (1..53) or (-53..-1);
+ * in some years, 53 or -53 will be out-of-range;
+ * if negative, counts backward from the end of the year:
+ *
+ *   Date.commercial(2022, 1, 1).to_s  # => "2022-01-03"
+ *   Date.commercial(2022, 52, 1).to_s # => "2022-12-26"
+ *
+ * Argument +cwday+ gives the indes of the weekday within the week,
+ * and should be in range (1..7) or (-7..-1);
+ * 1 or -7 is Monday;
+ * if negative, counts backward from the end of the week:
+ *
+ *   Date.commercial(2022, 1, 1).to_s  # => "2022-01-03"
+ *   Date.commercial(2022, 1, -7).to_s # => "2022-01-03"
+ *
+ * When +cweek+ is 1:
+ *
+ * - If January 1 is a Friday, Saturday, or Sunday,
+ *   the first week begins in the week after:
  *
- * Creates a date object denoting the given week date.
+ *     Date::ABBR_DAYNAMES[Date.new(2023, 1, 1).wday] # => "Sun"
+ *     Date.commercial(2023, 1, 1).to_s # => "2023-01-02"
+       Date.commercial(2023, 1, 7).to_s # => "2023-01-08"
  *
- * The week and the day of week should be a negative or a positive
- * number (as a relative week/day from the end of year/week when
- * negative).  They should not be zero.
+ * - Otherwise, the first week is the week of January 1,
+ *   which may mean some of the days fall on the year before:
  *
- *    Date.commercial(2001)	#=> #<Date: 2001-01-01 ...>
- *    Date.commercial(2002)	#=> #<Date: 2001-12-31 ...>
- *    Date.commercial(2001,5,6)	#=> #<Date: 2001-02-03 ...>
+ *     Date::ABBR_DAYNAMES[Date.new(2020, 1, 1).wday] # => "Wed"
+ *     Date.commercial(2020, 1, 1).to_s # => "2019-12-30"
+       Date.commercial(2020, 1, 7).to_s # => "2020-01-05"
  *
- * See also ::jd and ::new.
+ * See argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
+ *
+ * Related: Date.jd, Date.new, Date.ordinal.
  */
 static VALUE
 date_s_commercial(int argc, VALUE *argv, VALUE klass)
@@ -3547,6 +3653,7 @@ date_s_commercial(int argc, VALUE *argv, VALUE klass)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 date_s_weeknum(int argc, VALUE *argv, VALUE klass)
 {
@@ -3596,6 +3703,7 @@ date_s_weeknum(int argc, VALUE *argv, VALUE klass)
     return ret;
 }
 
+/* :nodoc: */
 static VALUE
 date_s_nth_kday(int argc, VALUE *argv, VALUE klass)
 {
@@ -3670,11 +3778,14 @@ static void set_sg(union DateData *, double);
 
 /*
  * call-seq:
- *    Date.today([start=Date::ITALY])  ->  date
+ *   Date.today(start = Date::ITALY) -> date
+ *
+ * Returns a new \Date object constructed from the present date:
+ *
+ *   Date.today.to_s # => "2022-07-06"
  *
- * Creates a date object denoting the present day.
+ * See argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
  *
- *    Date.today   #=> #<Date: 2011-06-11 ...>
  */
 static VALUE
 date_s_today(int argc, VALUE *argv, VALUE klass)
@@ -4265,16 +4376,20 @@ date_s__strptime_internal(int argc, VALUE *argv, VALUE klass,
 
 /*
  * call-seq:
- *    Date._strptime(string[, format='%F'])  ->  hash
+ *   Date._strptime(string, format = '%F') -> hash
  *
- * Parses the given representation of date and time with the given
- * template, and returns a hash of parsed elements.  _strptime does
- * not support specification of flags and width unlike strftime.
+ * Returns a hash of values parsed from +string+
+ * according to the given +format+:
  *
- *    Date._strptime('2001-02-03', '%Y-%m-%d')
- *				#=> {:year=>2001, :mon=>2, :mday=>3}
+ *   Date._strptime('2001-02-03', '%Y-%m-%d') # => {:year=>2001, :mon=>2, :mday=>3}
  *
- * See also strptime(3) and #strftime.
+ * For other formats, see
+ * {Formats for Dates and Times}[rdoc-ref:strftime_formatting.rdoc].
+ * (Unlike Date.strftime, does not support flags and width.)
+ *
+ * See also {strptime(3)}[https://man7.org/linux/man-pages/man3/strptime.3.html].
+ *
+ * Related: Date.strptime (returns a \Date object).
  */
 static VALUE
 date_s__strptime(int argc, VALUE *argv, VALUE klass)
@@ -4284,21 +4399,28 @@ date_s__strptime(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date.strptime([string='-4712-01-01'[, format='%F'[, start=Date::ITALY]]])  ->  date
+ *   Date.strptime(string = '-4712-01-01', format = '%F', start = Date::ITALY) -> date
  *
- * Parses the given representation of date and time with the given
- * template, and creates a date object.  strptime does not support
- * specification of flags and width unlike strftime.
+ * Returns a new \Date object with values parsed from +string+,
+ * according to the given +format+:
  *
- *    Date.strptime('2001-02-03', '%Y-%m-%d')	#=> #<Date: 2001-02-03 ...>
- *    Date.strptime('03-02-2001', '%d-%m-%Y')	#=> #<Date: 2001-02-03 ...>
- *    Date.strptime('2001-034', '%Y-%j')	#=> #<Date: 2001-02-03 ...>
- *    Date.strptime('2001-W05-6', '%G-W%V-%u')	#=> #<Date: 2001-02-03 ...>
- *    Date.strptime('2001 04 6', '%Y %U %w')	#=> #<Date: 2001-02-03 ...>
- *    Date.strptime('2001 05 6', '%Y %W %u')	#=> #<Date: 2001-02-03 ...>
- *    Date.strptime('sat3feb01', '%a%d%b%y')	#=> #<Date: 2001-02-03 ...>
+ *   Date.strptime('2001-02-03', '%Y-%m-%d')  # => #<Date: 2001-02-03>
+ *   Date.strptime('03-02-2001', '%d-%m-%Y')  # => #<Date: 2001-02-03>
+ *   Date.strptime('2001-034', '%Y-%j')       # => #<Date: 2001-02-03>
+ *   Date.strptime('2001-W05-6', '%G-W%V-%u') # => #<Date: 2001-02-03>
+ *   Date.strptime('2001 04 6', '%Y %U %w')   # => #<Date: 2001-02-03>
+ *   Date.strptime('2001 05 6', '%Y %W %u')   # => #<Date: 2001-02-03>
+ *   Date.strptime('sat3feb01', '%a%d%b%y')   # => #<Date: 2001-02-03>
  *
- * See also strptime(3) and #strftime.
+ * For other formats, see
+ * {Formats for Dates and Times}[rdoc-ref:strftime_formatting.rdoc].
+ * (Unlike Date.strftime, does not support flags and width.)
+ *
+ * See argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
+ *
+ * See also {strptime(3)}[https://man7.org/linux/man-pages/man3/strptime.3.html].
+ *
+ * Related: Date._strptime (returns a hash).
  */
 static VALUE
 date_s_strptime(int argc, VALUE *argv, VALUE klass)
@@ -4385,25 +4507,32 @@ date_s__parse_internal(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date._parse(string[, comp=true], limit: 128)  ->  hash
+ *   Date._parse(string, comp = true, limit: 128) -> hash
  *
- * Parses the given representation of date and time, and returns a
- * hash of parsed elements.
+ * <b>Note</b>:
+ * This method recognizes many forms in +string+,
+ * but it is not a validator.
+ * For formats, see
+ * {"Specialized Format Strings" in Formats for Dates and Times}[rdoc-ref:strftime_formatting.rdoc@Specialized+Format+Strings]
  *
- * This method *does not* function as a validator.  If the input
- * string does not match valid formats strictly, you may get a cryptic
- * result.  Should consider to use `Date._strptime` or
- * `DateTime._strptime` instead of this method as possible.
+ * If +string+ does not specify a valid date,
+ * the result is unpredictable;
+ * consider using Date._strptime instead.
  *
- * If the optional second argument is true and the detected year is in
- * the range "00" to "99", considers the year a 2-digit form and makes
- * it full.
+ * Returns a hash of values parsed from +string+:
  *
- *    Date._parse('2001-02-03')	#=> {:year=>2001, :mon=>2, :mday=>3}
+ *   Date._parse('2001-02-03') # => {:year=>2001, :mon=>2, :mday=>3}
  *
- * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ * If +comp+ is +true+ and the given year is in the range <tt>(0..99)</tt>,
+ * the current century is supplied;
+ * otherwise, the year is taken as given:
+ *
+ *   Date._parse('01-02-03', true)  # => {:year=>2001, :mon=>2, :mday=>3}
+ *   Date._parse('01-02-03', false) # => {:year=>1, :mon=>2, :mday=>3}
+ *
+ * See argument {limit}[rdoc-ref:Date@Argument+limit].
+ *
+ * Related: Date.parse(returns a \Date object).
  */
 static VALUE
 date_s__parse(int argc, VALUE *argv, VALUE klass)
@@ -4413,27 +4542,36 @@ date_s__parse(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date.parse(string='-4712-01-01'[, comp=true[, start=Date::ITALY]], limit: 128)  ->  date
+ *   Date.parse(string = '-4712-01-01', comp = true, start = Date::ITALY, limit: 128) -> date
  *
- * Parses the given representation of date and time, and creates a
- * date object.
+ * <b>Note</b>:
+ * This method recognizes many forms in +string+,
+ * but it is not a validator.
+ * For formats, see
+ * {"Specialized Format Strings" in Formats for Dates and Times}[rdoc-ref:strftime_formatting.rdoc@Specialized+Format+Strings]
+ * If +string+ does not specify a valid date,
+ * the result is unpredictable;
+ * consider using Date._strptime instead.
  *
- * This method *does not* function as a validator.  If the input
- * string does not match valid formats strictly, you may get a cryptic
- * result.  Should consider to use `Date.strptime` instead of this
- * method as possible.
+ * Returns a new \Date object with values parsed from +string+:
  *
- * If the optional second argument is true and the detected year is in
- * the range "00" to "99", considers the year a 2-digit form and makes
- * it full.
+ *   Date.parse('2001-02-03')   # => #<Date: 2001-02-03>
+ *   Date.parse('20010203')     # => #<Date: 2001-02-03>
+ *   Date.parse('3rd Feb 2001') # => #<Date: 2001-02-03>
  *
- *    Date.parse('2001-02-03')		#=> #<Date: 2001-02-03 ...>
- *    Date.parse('20010203')		#=> #<Date: 2001-02-03 ...>
- *    Date.parse('3rd Feb 2001')	#=> #<Date: 2001-02-03 ...>
+ * If +comp+ is +true+ and the given year is in the range <tt>(0..99)</tt>,
+ * the current century is supplied;
+ * otherwise, the year is taken as given:
  *
- * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ *   Date.parse('01-02-03', true)  # => #<Date: 2001-02-03>
+ *   Date.parse('01-02-03', false) # => #<Date: 0001-02-03>
+ *
+ * See:
+ *
+ * - Argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
+ * - Argument {limit}[rdoc-ref:Date@Argument+limit].
+ *
+ * Related: Date._parse (returns a hash).
  */
 static VALUE
 date_s_parse(int argc, VALUE *argv, VALUE klass)
@@ -4472,13 +4610,18 @@ VALUE date__jisx0301(VALUE);
 
 /*
  * call-seq:
- *    Date._iso8601(string, limit: 128)  ->  hash
+ *   Date._iso8601(string, limit: 128) -> hash
  *
- * Returns a hash of parsed elements.
+ * Returns a hash of values parsed from +string+, which should contain
+ * an {ISO 8601 formatted date}[rdoc-ref:strftime_formatting.rdoc@ISO+8601+Format+Specifications]:
  *
- * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ *   d = Date.new(2001, 2, 3)
+ *   s = d.iso8601    # => "2001-02-03"
+ *   Date._iso8601(s) # => {:mday=>3, :year=>2001, :mon=>2}
+ *
+ * See argument {limit}[rdoc-ref:Date@Argument+limit].
+ *
+ * Related: Date.iso8601 (returns a \Date object).
  */
 static VALUE
 date_s__iso8601(int argc, VALUE *argv, VALUE klass)
@@ -4493,18 +4636,22 @@ date_s__iso8601(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date.iso8601(string='-4712-01-01'[, start=Date::ITALY], limit: 128)  ->  date
+ *   Date.iso8601(string = '-4712-01-01', start = Date::ITALY, limit: 128) -> date
  *
- * Creates a new Date object by parsing from a string according to
- * some typical ISO 8601 formats.
+ * Returns a new \Date object with values parsed from +string+,
+ * which should contain
+ * an {ISO 8601 formatted date}[rdoc-ref:strftime_formatting.rdoc@ISO+8601+Format+Specifications]:
  *
- *    Date.iso8601('2001-02-03')	#=> #<Date: 2001-02-03 ...>
- *    Date.iso8601('20010203')		#=> #<Date: 2001-02-03 ...>
- *    Date.iso8601('2001-W05-6')	#=> #<Date: 2001-02-03 ...>
+ *   d = Date.new(2001, 2, 3)
+ *   s = d.iso8601   # => "2001-02-03"
+ *   Date.iso8601(s) # => #<Date: 2001-02-03>
  *
- * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ * See:
+ *
+ * - Argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
+ * - Argument {limit}[rdoc-ref:Date@Argument+limit].
+ *
+ * Related: Date._iso8601 (returns a hash).
  */
 static VALUE
 date_s_iso8601(int argc, VALUE *argv, VALUE klass)
@@ -4533,13 +4680,19 @@ date_s_iso8601(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date._rfc3339(string, limit: 128)  ->  hash
+ *   Date._rfc3339(string, limit: 128) -> hash
  *
- * Returns a hash of parsed elements.
+ * Returns a hash of values parsed from +string+, which should be a valid
+ * {RFC 3339 format}[rdoc-ref:strftime_formatting.rdoc@RFC+3339+Format]:
  *
- * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ *   d = Date.new(2001, 2, 3)
+ *   s = d.rfc3339     # => "2001-02-03T00:00:00+00:00"
+ *   Date._rfc3339(s)
+ *   # => {:year=>2001, :mon=>2, :mday=>3, :hour=>0, :min=>0, :sec=>0, :zone=>"+00:00", :offset=>0}
+ *
+ * See argument {limit}[rdoc-ref:Date@Argument+limit].
+ *
+ * Related: Date.rfc3339 (returns a \Date object).
  */
 static VALUE
 date_s__rfc3339(int argc, VALUE *argv, VALUE klass)
@@ -4554,16 +4707,22 @@ date_s__rfc3339(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date.rfc3339(string='-4712-01-01T00:00:00+00:00'[, start=Date::ITALY], limit: 128)  ->  date
+ *   Date.rfc3339(string = '-4712-01-01T00:00:00+00:00', start = Date::ITALY, limit: 128) -> date
  *
- * Creates a new Date object by parsing from a string according to
- * some typical RFC 3339 formats.
+ * Returns a new \Date object with values parsed from +string+,
+ * which should be a valid
+ * {RFC 3339 format}[rdoc-ref:strftime_formatting.rdoc@RFC+3339+Format]:
  *
- *    Date.rfc3339('2001-02-03T04:05:06+07:00')	#=> #<Date: 2001-02-03 ...>
+ *   d = Date.new(2001, 2, 3)
+ *   s = d.rfc3339   # => "2001-02-03T00:00:00+00:00"
+ *   Date.rfc3339(s) # => #<Date: 2001-02-03>
  *
- * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ * See:
+ *
+ * - Argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
+ * - Argument {limit}[rdoc-ref:Date@Argument+limit].
+ *
+ * Related: Date._rfc3339 (returns a hash).
  */
 static VALUE
 date_s_rfc3339(int argc, VALUE *argv, VALUE klass)
@@ -4592,13 +4751,18 @@ date_s_rfc3339(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date._xmlschema(string, limit: 128)  ->  hash
+ *   Date._xmlschema(string, limit: 128) -> hash
  *
- * Returns a hash of parsed elements.
+ * Returns a hash of values parsed from +string+, which should be a valid
+ * XML date format:
  *
- * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ *   d = Date.new(2001, 2, 3)
+ *   s = d.xmlschema    # => "2001-02-03"
+ *   Date._xmlschema(s) # => {:year=>2001, :mon=>2, :mday=>3}
+ *
+ * See argument {limit}[rdoc-ref:Date@Argument+limit].
+ *
+ * Related: Date.xmlschema (returns a \Date object).
  */
 static VALUE
 date_s__xmlschema(int argc, VALUE *argv, VALUE klass)
@@ -4613,16 +4777,21 @@ date_s__xmlschema(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date.xmlschema(string='-4712-01-01'[, start=Date::ITALY], limit: 128)  ->  date
+ *   Date.xmlschema(string = '-4712-01-01', start = Date::ITALY, limit: 128)  ->  date
  *
- * Creates a new Date object by parsing from a string according to
- * some typical XML Schema formats.
+ * Returns a new \Date object with values parsed from +string+,
+ * which should be a valid XML date format:
  *
- *    Date.xmlschema('2001-02-03')	#=> #<Date: 2001-02-03 ...>
+ *   d = Date.new(2001, 2, 3)
+ *   s = d.xmlschema   # => "2001-02-03"
+ *   Date.xmlschema(s) # => #<Date: 2001-02-03>
  *
- * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ * See:
+ *
+ * - Argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
+ * - Argument {limit}[rdoc-ref:Date@Argument+limit].
+ *
+ * Related: Date._xmlschema (returns a hash).
  */
 static VALUE
 date_s_xmlschema(int argc, VALUE *argv, VALUE klass)
@@ -4651,14 +4820,21 @@ date_s_xmlschema(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date._rfc2822(string, limit: 128)  ->  hash
- *    Date._rfc822(string, limit: 128)   ->  hash
+ *   Date._rfc2822(string, limit: 128) -> hash
  *
- * Returns a hash of parsed elements.
+ * Returns a hash of values parsed from +string+, which should be a valid
+ * {RFC 2822 date format}[rdoc-ref:strftime_formatting.rdoc@RFC+2822+Format]:
  *
- * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ *   d = Date.new(2001, 2, 3)
+ *   s = d.rfc2822 # => "Sat, 3 Feb 2001 00:00:00 +0000"
+ *   Date._rfc2822(s)
+ *   # => {:wday=>6, :mday=>3, :mon=>2, :year=>2001, :hour=>0, :min=>0, :sec=>0, :zone=>"+0000", :offset=>0}
+ *
+ * See argument {limit}[rdoc-ref:Date@Argument+limit].
+ *
+ * Date._rfc822 is an alias for Date._rfc2822.
+ *
+ * Related: Date.rfc2822 (returns a \Date object).
  */
 static VALUE
 date_s__rfc2822(int argc, VALUE *argv, VALUE klass)
@@ -4673,18 +4849,24 @@ date_s__rfc2822(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date.rfc2822(string='Mon, 1 Jan -4712 00:00:00 +0000'[, start=Date::ITALY], limit: 128)  ->  date
- *    Date.rfc822(string='Mon, 1 Jan -4712 00:00:00 +0000'[, start=Date::ITALY], limit: 128)   ->  date
+ *   Date.rfc2822(string = 'Mon, 1 Jan -4712 00:00:00 +0000', start = Date::ITALY, limit: 128) -> date
  *
- * Creates a new Date object by parsing from a string according to
- * some typical RFC 2822 formats.
+ * Returns a new \Date object with values parsed from +string+,
+ * which should be a valid
+ * {RFC 2822 date format}[rdoc-ref:strftime_formatting.rdoc@RFC+2822+Format]:
  *
- *    Date.rfc2822('Sat, 3 Feb 2001 00:00:00 +0000')
- *						#=> #<Date: 2001-02-03 ...>
+ *   d = Date.new(2001, 2, 3)
+ *   s = d.rfc2822   # => "Sat, 3 Feb 2001 00:00:00 +0000"
+ *   Date.rfc2822(s) # => #<Date: 2001-02-03>
  *
- * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ * See:
+ *
+ * - Argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
+ * - Argument {limit}[rdoc-ref:Date@Argument+limit].
+ *
+ * Date.rfc822 is an alias for Date.rfc2822.
+ *
+ * Related: Date._rfc2822 (returns a hash).
  */
 static VALUE
 date_s_rfc2822(int argc, VALUE *argv, VALUE klass)
@@ -4712,13 +4894,17 @@ date_s_rfc2822(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date._httpdate(string, limit: 128)  ->  hash
+ *   Date._httpdate(string, limit: 128) -> hash
  *
- * Returns a hash of parsed elements.
+ * Returns a hash of values parsed from +string+, which should be a valid
+ * {HTTP date format}[rdoc-ref:strftime_formatting.rdoc@HTTP+Format]:
  *
- * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ *   d = Date.new(2001, 2, 3)
+ *   s = d.httpdate # => "Sat, 03 Feb 2001 00:00:00 GMT"
+ *   Date._httpdate(s)
+ *   # => {:wday=>6, :mday=>3, :mon=>2, :year=>2001, :hour=>0, :min=>0, :sec=>0, :zone=>"GMT", :offset=>0}
+ *
+ * Related: Date.httpdate (returns a \Date object).
  */
 static VALUE
 date_s__httpdate(int argc, VALUE *argv, VALUE klass)
@@ -4733,17 +4919,22 @@ date_s__httpdate(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date.httpdate(string='Mon, 01 Jan -4712 00:00:00 GMT'[, start=Date::ITALY], limit: 128)  ->  date
+ *   Date.httpdate(string = 'Mon, 01 Jan -4712 00:00:00 GMT', start = Date::ITALY, limit: 128) -> date
  *
- * Creates a new Date object by parsing from a string according to
- * some RFC 2616 format.
+ * Returns a new \Date object with values parsed from +string+,
+ * which should be a valid
+ * {HTTP date format}[rdoc-ref:strftime_formatting.rdoc@HTTP+Format]:
  *
- *    Date.httpdate('Sat, 03 Feb 2001 00:00:00 GMT')
- *						#=> #<Date: 2001-02-03 ...>
+ *   d = Date.new(2001, 2, 3)
+     s = d.httpdate   # => "Sat, 03 Feb 2001 00:00:00 GMT"
+     Date.httpdate(s) # => #<Date: 2001-02-03>
  *
- * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ * See:
+ *
+ * - Argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
+ * - Argument {limit}[rdoc-ref:Date@Argument+limit].
+ *
+ * Related: Date._httpdate (returns a hash).
  */
 static VALUE
 date_s_httpdate(int argc, VALUE *argv, VALUE klass)
@@ -4771,13 +4962,18 @@ date_s_httpdate(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date._jisx0301(string, limit: 128)  ->  hash
+ *   Date._jisx0301(string, limit: 128) -> hash
  *
- * Returns a hash of parsed elements.
+ * Returns a hash of values parsed from +string+, which should be a valid
+ * {JIS X 0301 date format}[rdoc-ref:strftime_formatting.rdoc@JIS+X+0301+Format]:
  *
- * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ *   d = Date.new(2001, 2, 3)
+ *   s = d.jisx0301    # => "H13.02.03"
+ *   Date._jisx0301(s) # => {:year=>2001, :mon=>2, :mday=>3}
+ *
+ * See argument {limit}[rdoc-ref:Date@Argument+limit].
+ *
+ * Related: Date.jisx0301 (returns a \Date object).
  */
 static VALUE
 date_s__jisx0301(int argc, VALUE *argv, VALUE klass)
@@ -4792,20 +4988,25 @@ date_s__jisx0301(int argc, VALUE *argv, VALUE klass)
 
 /*
  * call-seq:
- *    Date.jisx0301(string='-4712-01-01'[, start=Date::ITALY], limit: 128)  ->  date
+ *   Date.jisx0301(string = '-4712-01-01', start = Date::ITALY, limit: 128) -> date
  *
- * Creates a new Date object by parsing from a string according to
- * some typical JIS X 0301 formats.
+ * Returns a new \Date object with values parsed from +string+,
+ * which should be a valid {JIS X 0301 format}[rdoc-ref:strftime_formatting.rdoc@JIS+X+0301+Format]:
  *
- *    Date.jisx0301('H13.02.03')		#=> #<Date: 2001-02-03 ...>
+ *   d = Date.new(2001, 2, 3)
+ *   s = d.jisx0301   # => "H13.02.03"
+ *   Date.jisx0301(s) # => #<Date: 2001-02-03>
  *
  * For no-era year, legacy format, Heisei is assumed.
  *
- *    Date.jisx0301('13.02.03') 		#=> #<Date: 2001-02-03 ...>
+ *   Date.jisx0301('13.02.03') # => #<Date: 2001-02-03>
  *
- * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ * See:
+ *
+ * - Argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
+ * - Argument {limit}[rdoc-ref:Date@Argument+limit].
+ *
+ * Related: Date._jisx0301 (returns a hash).
  */
 static VALUE
 date_s_jisx0301(int argc, VALUE *argv, VALUE klass)
@@ -4997,6 +5198,7 @@ d_lite_initialize_copy(VALUE copy, VALUE date)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 d_lite_fill(VALUE self)
 {
@@ -5086,12 +5288,15 @@ d_lite_mjd(VALUE self)
 
 /*
  * call-seq:
- *    d.ld  ->  integer
+ *   ld -> integer
  *
- * Returns the Lilian day number.  This is a whole number, which is
- * adjusted by the offset as the local time.
+ * Returns the
+ * {Lilian day number}[https://en.wikipedia.org/wiki/Lilian_date],
+ * which is the number of days since the beginning of the Gregorian
+ * calendar, October 15, 1582.
+ *
+ *   Date.new(2001, 2, 3).ld # => 152784
  *
- *     Date.new(2001,2,3).ld		#=> 152784
  */
 static VALUE
 d_lite_ld(VALUE self)
@@ -5102,12 +5307,13 @@ d_lite_ld(VALUE self)
 
 /*
  * call-seq:
- *    d.year  ->  integer
+ *   year -> integer
+ *
+ * Returns the year:
  *
- * Returns the year.
+ *   Date.new(2001, 2, 3).year    # => 2001
+ *   (Date.new(1, 1, 1) - 1).year # => 0
  *
- *    Date.new(2001,2,3).year		#=> 2001
- *    (Date.new(1,1,1) - 1).year	#=> 0
  */
 static VALUE
 d_lite_year(VALUE self)
@@ -5118,11 +5324,12 @@ d_lite_year(VALUE self)
 
 /*
  * call-seq:
- *    d.yday  ->  fixnum
+ *   yday -> integer
+ *
+ * Returns the day of the year, in range (1..366):
  *
- * Returns the day of the year (1-366).
+ *   Date.new(2001, 2, 3).yday # => 34
  *
- *    Date.new(2001,2,3).yday		#=> 34
  */
 static VALUE
 d_lite_yday(VALUE self)
@@ -5133,12 +5340,13 @@ d_lite_yday(VALUE self)
 
 /*
  * call-seq:
- *    d.mon    ->  fixnum
- *    d.month  ->  fixnum
+ *   mon -> integer
  *
- * Returns the month (1-12).
+ * Returns the month in range (1..12):
  *
- *    Date.new(2001,2,3).mon		#=> 2
+ *   Date.new(2001, 2, 3).mon # => 2
+ *
+ * Date#month is an alias for Date#mon.
  */
 static VALUE
 d_lite_mon(VALUE self)
@@ -5149,12 +5357,13 @@ d_lite_mon(VALUE self)
 
 /*
  * call-seq:
- *    d.mday  ->  fixnum
- *    d.day   ->  fixnum
+ *   mday -> integer
+ *
+ * Returns the day of the month in range (1..31):
  *
- * Returns the day of the month (1-31).
+ *   Date.new(2001, 2, 3).mday # => 3
  *
- *    Date.new(2001,2,3).mday		#=> 3
+ * Date#day is an alias for Date#mday.
  */
 static VALUE
 d_lite_mday(VALUE self)
@@ -5165,11 +5374,12 @@ d_lite_mday(VALUE self)
 
 /*
  * call-seq:
- *    d.day_fraction  ->  rational
+ *   day_fraction -> rational
+ *
+ * Returns the fractional part of the day in range (Rational(0, 1)...Rational(1, 1)):
  *
- * Returns the fractional part of the day.
+ *   DateTime.new(2001,2,3,12).day_fraction # => (1/2)
  *
- *    DateTime.new(2001,2,3,12).day_fraction	#=> (1/2)
  */
 static VALUE
 d_lite_day_fraction(VALUE self)
@@ -5182,12 +5392,14 @@ d_lite_day_fraction(VALUE self)
 
 /*
  * call-seq:
- *    d.cwyear  ->  integer
+ *   cwyear -> integer
  *
- * Returns the calendar week based year.
+ * Returns commercial-date year for +self+
+ * (see Date.commercial):
+ *
+ *   Date.new(2001, 2, 3).cwyear # => 2001
+ *   Date.new(2000, 1, 1).cwyear # => 1999
  *
- *    Date.new(2001,2,3).cwyear		#=> 2001
- *    Date.new(2000,1,1).cwyear		#=> 1999
  */
 static VALUE
 d_lite_cwyear(VALUE self)
@@ -5198,11 +5410,13 @@ d_lite_cwyear(VALUE self)
 
 /*
  * call-seq:
- *    d.cweek  ->  fixnum
+ *   cweek -> integer
+ *
+ * Returns commercial-date week index for +self+
+ * (see Date.commercial):
  *
- * Returns the calendar week number (1-53).
+ *   Date.new(2001, 2, 3).cweek # => 5
  *
- *    Date.new(2001,2,3).cweek		#=> 5
  */
 static VALUE
 d_lite_cweek(VALUE self)
@@ -5213,11 +5427,14 @@ d_lite_cweek(VALUE self)
 
 /*
  * call-seq:
- *    d.cwday  ->  fixnum
+ *   cwday -> integer
  *
- * Returns the day of calendar week (1-7, Monday is 1).
+ * Returns the commercial-date weekday index for +self+
+ * (see Date.commercial);
+ * 1 is Monday:
+ *
+ *   Date.new(2001, 2, 3).cwday # => 6
  *
- *    Date.new(2001,2,3).cwday		#=> 6
  */
 static VALUE
 d_lite_cwday(VALUE self)
@@ -5227,6 +5444,7 @@ d_lite_cwday(VALUE self)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 d_lite_wnum0(VALUE self)
 {
@@ -5234,6 +5452,7 @@ d_lite_wnum0(VALUE self)
     return INT2FIX(m_wnum0(dat));
 }
 
+/* :nodoc: */
 static VALUE
 d_lite_wnum1(VALUE self)
 {
@@ -5244,11 +5463,12 @@ d_lite_wnum1(VALUE self)
 
 /*
  * call-seq:
- *    d.wday  ->  fixnum
+ *   wday -> integer
  *
- * Returns the day of week (0-6, Sunday is zero).
+ * Returns the day of week in range (0..6); Sunday is 0:
+ *
+ *   Date.new(2001, 2, 3).wday # => 6
  *
- *    Date.new(2001,2,3).wday		#=> 6
  */
 static VALUE
 d_lite_wday(VALUE self)
@@ -5259,9 +5479,9 @@ d_lite_wday(VALUE self)
 
 /*
  * call-seq:
- *    d.sunday?  ->  bool
+ *   sunday? -> true or false
  *
- * Returns true if the date is Sunday.
+ * Returns +true+ if +self+ is a Sunday, +false+ otherwise.
  */
 static VALUE
 d_lite_sunday_p(VALUE self)
@@ -5272,9 +5492,9 @@ d_lite_sunday_p(VALUE self)
 
 /*
  * call-seq:
- *    d.monday?  ->  bool
+ *   monday? -> true or false
  *
- * Returns true if the date is Monday.
+ * Returns +true+ if +self+ is a Monday, +false+ otherwise.
  */
 static VALUE
 d_lite_monday_p(VALUE self)
@@ -5285,9 +5505,9 @@ d_lite_monday_p(VALUE self)
 
 /*
  * call-seq:
- *    d.tuesday?  ->  bool
+ *   tuesday? -> true or false
  *
- * Returns true if the date is Tuesday.
+ * Returns +true+ if +self+ is a Tuesday, +false+ otherwise.
  */
 static VALUE
 d_lite_tuesday_p(VALUE self)
@@ -5298,9 +5518,9 @@ d_lite_tuesday_p(VALUE self)
 
 /*
  * call-seq:
- *    d.wednesday?  ->  bool
+ *   wednesday? -> true or false
  *
- * Returns true if the date is Wednesday.
+ * Returns +true+ if +self+ is a Wednesday, +false+ otherwise.
  */
 static VALUE
 d_lite_wednesday_p(VALUE self)
@@ -5311,9 +5531,9 @@ d_lite_wednesday_p(VALUE self)
 
 /*
  * call-seq:
- *    d.thursday?  ->  bool
+ *   thursday? -> true or false
  *
- * Returns true if the date is Thursday.
+ * Returns +true+ if +self+ is a Thursday, +false+ otherwise.
  */
 static VALUE
 d_lite_thursday_p(VALUE self)
@@ -5324,9 +5544,9 @@ d_lite_thursday_p(VALUE self)
 
 /*
  * call-seq:
- *    d.friday?  ->  bool
+ *   friday? -> true or false
  *
- * Returns true if the date is Friday.
+ * Returns +true+ if +self+ is a Friday, +false+ otherwise.
  */
 static VALUE
 d_lite_friday_p(VALUE self)
@@ -5337,9 +5557,9 @@ d_lite_friday_p(VALUE self)
 
 /*
  * call-seq:
- *    d.saturday?  ->  bool
+ *   saturday? -> true or false
  *
- * Returns true if the date is Saturday.
+ * Returns +true+ if +self+ is a Saturday, +false+ otherwise.
  */
 static VALUE
 d_lite_saturday_p(VALUE self)
@@ -5349,6 +5569,7 @@ d_lite_saturday_p(VALUE self)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 d_lite_nth_kday_p(VALUE self, VALUE n, VALUE k)
 {
@@ -5370,11 +5591,12 @@ d_lite_nth_kday_p(VALUE self, VALUE n, VALUE k)
 
 /*
  * call-seq:
- *    d.hour  ->  fixnum
+ *   hour -> integer
  *
- * Returns the hour (0-23).
+ * Returns the hour in range (0..23):
+ *
+ *   DateTime.new(2001, 2, 3, 4, 5, 6).hour # => 4
  *
- *    DateTime.new(2001,2,3,4,5,6).hour		#=> 4
  */
 static VALUE
 d_lite_hour(VALUE self)
@@ -5385,12 +5607,13 @@ d_lite_hour(VALUE self)
 
 /*
  * call-seq:
- *    d.min     ->  fixnum
- *    d.minute  ->  fixnum
+ *   min -> integer
+ *
+ * Returns the minute in range (0..59):
  *
- * Returns the minute (0-59).
+ *   DateTime.new(2001, 2, 3, 4, 5, 6).min # => 5
  *
- *    DateTime.new(2001,2,3,4,5,6).min		#=> 5
+ * Date#minute is an alias for Date#min.
  */
 static VALUE
 d_lite_min(VALUE self)
@@ -5401,12 +5624,13 @@ d_lite_min(VALUE self)
 
 /*
  * call-seq:
- *    d.sec     ->  fixnum
- *    d.second  ->  fixnum
+ *   sec -> integer
+ *
+ * Returns the second in range (0..59):
  *
- * Returns the second (0-59).
+ *   DateTime.new(2001, 2, 3, 4, 5, 6).sec # => 6
  *
- *    DateTime.new(2001,2,3,4,5,6).sec		#=> 6
+ * Date#second is an alias for Date#sec.
  */
 static VALUE
 d_lite_sec(VALUE self)
@@ -5417,12 +5641,14 @@ d_lite_sec(VALUE self)
 
 /*
  * call-seq:
- *    d.sec_fraction     ->  rational
- *    d.second_fraction  ->  rational
+ *   sec_fraction -> rational
  *
- * Returns the fractional part of the second.
+ * Returns the fractional part of the second in range
+ * (Rational(0, 1)...Rational(1, 1)):
  *
- *    DateTime.new(2001,2,3,4,5,6.5).sec_fraction	#=> (1/2)
+ *   DateTime.new(2001, 2, 3, 4, 5, 6.5).sec_fraction # => (1/2)
+ *
+ * Date#second_fraction is an alias for Date#sec_fraction.
  */
 static VALUE
 d_lite_sec_fraction(VALUE self)
@@ -5463,12 +5689,14 @@ d_lite_zone(VALUE self)
 
 /*
  * call-seq:
- *    d.julian?  ->  bool
+ *   d.julian? -> true or false
+ *
+ * Returns +true+ if the date is before the date of calendar reform,
+ * +false+ otherwise:
  *
- * Returns true if the date is before the day of calendar reform.
+ *   (Date.new(1582, 10, 15) - 1).julian? # => true
+ *   Date.new(1582, 10, 15).julian?       # => false
  *
- *     Date.new(1582,10,15).julian?		#=> false
- *     (Date.new(1582,10,15) - 1).julian?	#=> true
  */
 static VALUE
 d_lite_julian_p(VALUE self)
@@ -5479,12 +5707,14 @@ d_lite_julian_p(VALUE self)
 
 /*
  * call-seq:
- *    d.gregorian?  ->  bool
+ *   gregorian? -> true or false
  *
- * Returns true if the date is on or after the day of calendar reform.
+ * Returns +true+ if the date is on or after
+ * the date of calendar reform, +false+ otherwise:
+ *
+ *   Date.new(1582, 10, 15).gregorian?       # => true
+ *   (Date.new(1582, 10, 15) - 1).gregorian? # => false
  *
- *     Date.new(1582,10,15).gregorian?		#=> true
- *     (Date.new(1582,10,15) - 1).gregorian?	#=> false
  */
 static VALUE
 d_lite_gregorian_p(VALUE self)
@@ -5495,12 +5725,13 @@ d_lite_gregorian_p(VALUE self)
 
 /*
  * call-seq:
- *    d.leap?  ->  bool
+ *   leap? -> true or false
+ *
+ * Returns +true+ if the year is a leap year, +false+ otherwise:
  *
- * Returns true if the year is a leap year.
+ *   Date.new(2000).leap? # => true
+ *   Date.new(2001).leap? # => false
  *
- *    Date.new(2000).leap?	#=> true
- *    Date.new(2001).leap?	#=> false
  */
 static VALUE
 d_lite_leap_p(VALUE self)
@@ -5519,12 +5750,25 @@ d_lite_leap_p(VALUE self)
 
 /*
  * call-seq:
- *    d.start  ->  float
+ *   start -> float
+ *
+ * Returns the Julian start date for calendar reform;
+ * if not an infinity, the returned value is suitable
+ * for passing to Date#jd:
+ *
+ *   d = Date.new(2001, 2, 3, Date::ITALY)
+ *   s = d.start     # => 2299161.0
+ *   Date.jd(s).to_s # => "1582-10-15"
+ *
+ *   d = Date.new(2001, 2, 3, Date::ENGLAND)
+ *   s = d.start     # => 2361222.0
+ *   Date.jd(s).to_s # => "1752-09-14"
+ *
+ *   Date.new(2001, 2, 3, Date::GREGORIAN).start # => -Infinity
+ *   Date.new(2001, 2, 3, Date::JULIAN).start    # => Infinity
  *
- * Returns the Julian day number denoting the day of calendar reform.
+ * See argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
  *
- *    Date.new(2001,2,3).start			#=> 2299161.0
- *    Date.new(2001,2,3,Date::GREGORIAN).start	#=> -Infinity
  */
 static VALUE
 d_lite_start(VALUE self)
@@ -5589,12 +5833,17 @@ dup_obj_with_new_start(VALUE obj, double sg)
 
 /*
  * call-seq:
- *    d.new_start([start=Date::ITALY])  ->  date
+ *   new_start(start = Date::ITALY]) -> new_date
  *
- * Duplicates self and resets its day of calendar reform.
+ * Returns a copy of +self+ with the given +start+ value:
+ *
+ *   d0 = Date.new(2000, 2, 3)
+ *   d0.julian? # => false
+ *   d1 = d0.new_start(Date::JULIAN)
+ *   d1.julian? # => true
+ *
+ * See argument {start}[rdoc-ref:calendars.rdoc@Argument+start].
  *
- *    d = Date.new(1582,10,15)
- *    d.new_start(Date::JULIAN)		#=> #<Date: 1582-10-05 ...>
  */
 static VALUE
 d_lite_new_start(int argc, VALUE *argv, VALUE self)
@@ -5613,9 +5862,10 @@ d_lite_new_start(int argc, VALUE *argv, VALUE self)
 
 /*
  * call-seq:
- *    d.italy  ->  date
+ *   italy -> new_date
+ *
+ * Equivalent to Date#new_start with argument Date::ITALY.
  *
- * This method is equivalent to new_start(Date::ITALY).
  */
 static VALUE
 d_lite_italy(VALUE self)
@@ -5625,9 +5875,9 @@ d_lite_italy(VALUE self)
 
 /*
  * call-seq:
- *    d.england  ->  date
+ *   england -> new_date
  *
- * This method is equivalent to new_start(Date::ENGLAND).
+ * Equivalent to Date#new_start with argument Date::ENGLAND.
  */
 static VALUE
 d_lite_england(VALUE self)
@@ -5637,9 +5887,9 @@ d_lite_england(VALUE self)
 
 /*
  * call-seq:
- *    d.julian  ->  date
+ *   julian -> new_date
  *
- * This method is equivalent to new_start(Date::JULIAN).
+ * Equivalent to Date#new_start with argument Date::JULIAN.
  */
 static VALUE
 d_lite_julian(VALUE self)
@@ -5649,9 +5899,9 @@ d_lite_julian(VALUE self)
 
 /*
  * call-seq:
- *    d.gregorian  ->  date
+ *   gregorian -> new_date
  *
- * This method is equivalent to new_start(Date::GREGORIAN).
+ * Equivalent to Date#new_start with argument Date::GREGORIAN.
  */
 static VALUE
 d_lite_gregorian(VALUE self)
@@ -6132,9 +6382,9 @@ d_lite_minus(VALUE self, VALUE other)
 
 /*
  * call-seq:
- *    d.next_day([n=1])  ->  date
+ *   next_day(n = 1) -> new_date
  *
- * This method is equivalent to d + n.
+ * Equivalent to Date#+ with argument +n+.
  */
 static VALUE
 d_lite_next_day(int argc, VALUE *argv, VALUE self)
@@ -6149,9 +6399,9 @@ d_lite_next_day(int argc, VALUE *argv, VALUE self)
 
 /*
  * call-seq:
- *    d.prev_day([n=1])  ->  date
+ *   prev_day(n = 1) -> new_date
  *
- * This method is equivalent to d - n.
+ * Equivalent to Date#- with argument +n+.
  */
 static VALUE
 d_lite_prev_day(int argc, VALUE *argv, VALUE self)
@@ -6166,10 +6416,15 @@ d_lite_prev_day(int argc, VALUE *argv, VALUE self)
 
 /*
  * call-seq:
- *    d.succ  ->  date
- *    d.next  ->  date
+ *   d.next -> new_date
+ *
+ * Returns a new \Date object representing the following day:
+ *
+ *   d = Date.new(2001, 2, 3)
+ *   d.to_s      # => "2001-02-03"
+ *   d.next.to_s # => "2001-02-04"
  *
- * Returns a date object denoting the following day.
+ * Date#succ is an alias for Date#next.
  */
 static VALUE
 d_lite_next(VALUE self)
@@ -6179,26 +6434,30 @@ d_lite_next(VALUE self)
 
 /*
  * call-seq:
- *    d >> n  ->  date
+ *   d >> n -> new_date
  *
- * Returns a date object pointing +n+ months after self.
- * The argument +n+ should be a numeric value.
+ * Returns a new \Date object representing the date
+ * +n+ months later; +n+ should be a numeric:
  *
- *    Date.new(2001,2,3)  >>  1   #=> #<Date: 2001-03-03 ...>
- *    Date.new(2001,2,3)  >> -2   #=> #<Date: 2000-12-03 ...>
+ *   (Date.new(2001, 2, 3) >> 1).to_s  # => "2001-03-03"
+ *   (Date.new(2001, 2, 3) >> -2).to_s # => "2000-12-03"
  *
- * When the same day does not exist for the corresponding month,
- * the last day of the month is used instead:
+ * When the same day does not exist for the new month,
+ * the last day of that month is used instead:
  *
- *    Date.new(2001,1,28) >> 1   #=> #<Date: 2001-02-28 ...>
- *    Date.new(2001,1,31) >> 1   #=> #<Date: 2001-02-28 ...>
+ *   (Date.new(2001, 1, 31) >> 1).to_s  # => "2001-02-28"
+ *   (Date.new(2001, 1, 31) >> -4).to_s # => "2000-09-30"
  *
- * This also results in the following, possibly unexpected, behavior:
+ * This results in the following, possibly unexpected, behaviors:
  *
- *    Date.new(2001,1,31) >> 2         #=> #<Date: 2001-03-31 ...>
- *    Date.new(2001,1,31) >> 1 >> 1    #=> #<Date: 2001-03-28 ...>
+ *   d0 = Date.new(2001, 1, 31)
+ *   d1 = d0 >> 1 # => #<Date: 2001-02-28>
+ *   d2 = d1 >> 1 # => #<Date: 2001-03-28>
+ *
+ *   d0 = Date.new(2001, 1, 31)
+ *   d1 = d0 >> 1  # => #<Date: 2001-02-28>
+ *   d2 = d1 >> -1 # => #<Date: 2001-01-28>
  *
- *    Date.new(2001,1,31) >> 1 >> -1   #=> #<Date: 2001-01-28 ...>
  */
 static VALUE
 d_lite_rshift(VALUE self, VALUE other)
@@ -6243,24 +6502,28 @@ d_lite_rshift(VALUE self, VALUE other)
  * call-seq:
  *    d << n  ->  date
  *
- * Returns a date object pointing +n+ months before self.
- * The argument +n+ should be a numeric value.
+ * Returns a new \Date object representing the date
+ * +n+ months earlier; +n+ should be a numeric:
+ *
+ *   (Date.new(2001, 2, 3) << 1).to_s  # => "2001-01-03"
+ *   (Date.new(2001, 2, 3) << -2).to_s # => "2001-04-03"
  *
- *    Date.new(2001,2,3)  <<  1   #=> #<Date: 2001-01-03 ...>
- *    Date.new(2001,2,3)  << -2   #=> #<Date: 2001-04-03 ...>
+ * When the same day does not exist for the new month,
+ * the last day of that month is used instead:
  *
- * When the same day does not exist for the corresponding month,
- * the last day of the month is used instead:
+ *   (Date.new(2001, 3, 31) << 1).to_s  # => "2001-02-28"
+ *   (Date.new(2001, 3, 31) << -6).to_s # => "2001-09-30"
  *
- *    Date.new(2001,3,28) << 1   #=> #<Date: 2001-02-28 ...>
- *    Date.new(2001,3,31) << 1   #=> #<Date: 2001-02-28 ...>
+ * This results in the following, possibly unexpected, behaviors:
  *
- * This also results in the following, possibly unexpected, behavior:
+ *   d0 = Date.new(2001, 3, 31)
+ *   d0 << 2      # => #<Date: 2001-01-31>
+ *   d0 << 1 << 1 # => #<Date: 2001-01-28>
  *
- *    Date.new(2001,3,31) << 2         #=> #<Date: 2001-01-31 ...>
- *    Date.new(2001,3,31) << 1 << 1    #=> #<Date: 2001-01-28 ...>
+ *   d0 = Date.new(2001, 3, 31)
+ *   d1 = d0 << 1  # => #<Date: 2001-02-28>
+ *   d2 = d1 << -1 # => #<Date: 2001-03-28>
  *
- *    Date.new(2001,3,31) << 1 << -1   #=> #<Date: 2001-03-28 ...>
  */
 static VALUE
 d_lite_lshift(VALUE self, VALUE other)
@@ -6271,11 +6534,9 @@ d_lite_lshift(VALUE self, VALUE other)
 
 /*
  * call-seq:
- *    d.next_month([n=1])  ->  date
- *
- * This method is equivalent to d >> n.
+ *   next_month(n = 1) -> new_date
  *
- * See Date#>> for examples.
+ * Equivalent to #>> with argument +n+.
  */
 static VALUE
 d_lite_next_month(int argc, VALUE *argv, VALUE self)
@@ -6290,11 +6551,9 @@ d_lite_next_month(int argc, VALUE *argv, VALUE self)
 
 /*
  * call-seq:
- *    d.prev_month([n=1])  ->  date
+ *   prev_month(n = 1) -> new_date
  *
- * This method is equivalent to d << n.
- *
- * See Date#<< for examples.
+ * Equivalent to #<< with argument +n+.
  */
 static VALUE
 d_lite_prev_month(int argc, VALUE *argv, VALUE self)
@@ -6309,15 +6568,9 @@ d_lite_prev_month(int argc, VALUE *argv, VALUE self)
 
 /*
  * call-seq:
- *    d.next_year([n=1])  ->  date
- *
- * This method is equivalent to d >> (n * 12).
- *
- *    Date.new(2001,2,3).next_year      #=> #<Date: 2002-02-03 ...>
- *    Date.new(2008,2,29).next_year     #=> #<Date: 2009-02-28 ...>
- *    Date.new(2008,2,29).next_year(4)  #=> #<Date: 2012-02-29 ...>
+ *   next_year(n = 1) -> new_date
  *
- * See also Date#>>.
+ * Equivalent to #>> with argument <tt>n * 12</tt>.
  */
 static VALUE
 d_lite_next_year(int argc, VALUE *argv, VALUE self)
@@ -6332,15 +6585,9 @@ d_lite_next_year(int argc, VALUE *argv, VALUE self)
 
 /*
  * call-seq:
- *    d.prev_year([n=1])  ->  date
+ *   prev_year(n = 1) -> new_date
  *
- * This method is equivalent to d << (n * 12).
- *
- *    Date.new(2001,2,3).prev_year      #=> #<Date: 2000-02-03 ...>
- *    Date.new(2008,2,29).prev_year     #=> #<Date: 2007-02-28 ...>
- *    Date.new(2008,2,29).prev_year(4)  #=> #<Date: 2004-02-29 ...>
- *
- * See also Date#<<.
+ * Equivalent to #<< with argument <tt>n * 12</tt>.
  */
 static VALUE
 d_lite_prev_year(int argc, VALUE *argv, VALUE self)
@@ -6357,14 +6604,33 @@ static VALUE d_lite_cmp(VALUE, VALUE);
 
 /*
  * call-seq:
- *    d.step(limit[, step=1])              ->  enumerator
- *    d.step(limit[, step=1]){|date| ...}  ->  self
+ *   step(limit, step = 1){|date| ... } -> self
+ *
+ * Calls the block with specified dates;
+ * returns +self+.
+ *
+ * - The first +date+ is +self+.
+ * - Each successive +date+ is <tt>date + step</tt>,
+ *   where +step+ is the numeric step size in days.
+ * - The last date is the last one that is before or equal to +limit+,
+ *   which should be a \Date object.
+ *
+ * Example:
  *
- * Iterates evaluation of the given block, which takes a date object.
- * The limit should be a date object.
+ *   limit = Date.new(2001, 12, 31)
+ *   Date.new(2001).step(limit){|date| p date.to_s if date.mday == 31 }
  *
- *    Date.new(2001).step(Date.new(2001,-1,-1)).select{|d| d.sunday?}.size
- *				#=> 52
+ * Output:
+ *
+ *   "2001-01-31"
+ *   "2001-03-31"
+ *   "2001-05-31"
+ *   "2001-07-31"
+ *   "2001-08-31"
+ *   "2001-10-31"
+ *   "2001-12-31"
+ *
+ * Returns an Enumerator if no block is given.
  */
 static VALUE
 d_lite_step(int argc, VALUE *argv, VALUE self)
@@ -6407,10 +6673,9 @@ d_lite_step(int argc, VALUE *argv, VALUE self)
 
 /*
  * call-seq:
- *    d.upto(max)              ->  enumerator
- *    d.upto(max){|date| ...}  ->  self
+ *   upto(max){|date| ... } -> self
  *
- * This method is equivalent to step(max, 1){|date| ...}.
+ * Equivalent to #step with arguments +max+ and +1+.
  */
 static VALUE
 d_lite_upto(VALUE self, VALUE max)
@@ -6429,10 +6694,9 @@ d_lite_upto(VALUE self, VALUE max)
 
 /*
  * call-seq:
- *    d.downto(min)              ->  enumerator
- *    d.downto(min){|date| ...}  ->  self
+ *   downto(min){|date| ... } -> self
  *
- * This method is equivalent to step(min, -1){|date| ...}.
+ * Equivalent to #step with arguments +min+ and <tt>-1</tt>.
  */
 static VALUE
 d_lite_downto(VALUE self, VALUE min)
@@ -6520,19 +6784,43 @@ cmp_dd(VALUE self, VALUE other)
 
 /*
  * call-seq:
- *    d <=> other  -> -1, 0, +1 or nil
+ *   self <=> other  -> -1, 0, 1 or nil
+ *
+ * Compares +self+ and +other+, returning:
+ *
+ * - <tt>-1</tt> if +other+ is larger.
+ * - <tt>0</tt> if the two are equal.
+ * - <tt>1</tt> if +other+ is smaller.
+ * - +nil+ if the two are incomparable.
+ *
+ * Argument +other+ may be:
+ *
+ * - Another \Date object:
+ *
+ *     d = Date.new(2022, 7, 27) # => #<Date: 2022-07-27 ((2459788j,0s,0n),+0s,2299161j)>
+ *     prev_date = d.prev_day    # => #<Date: 2022-07-26 ((2459787j,0s,0n),+0s,2299161j)>
+ *     next_date = d.next_day    # => #<Date: 2022-07-28 ((2459789j,0s,0n),+0s,2299161j)>
+ *     d <=> next_date           # => -1
+ *     d <=> d                   # => 0
+ *     d <=> prev_date           # => 1
+ *
+ * - A DateTime object:
+ *
+ *     d <=> DateTime.new(2022, 7, 26) # => 1
+ *     d <=> DateTime.new(2022, 7, 27) # => 0
+ *     d <=> DateTime.new(2022, 7, 28) # => -1
+ *
+ * - A numeric (compares <tt>self.ajd</tt> to +other+):
+ *
+ *     d <=> 2459788 # => -1
+ *     d <=> 2459787 # => 1
+ *     d <=> 2459786 # => 1
+ *     d <=> d.ajd   # => 0
  *
- * Compares the two dates and returns -1, zero, 1 or nil.  The other
- * should be a date object or a numeric value as an astronomical
- * Julian day number.
+ * - Any other object:
  *
- *    Date.new(2001,2,3) <=> Date.new(2001,2,4)   #=> -1
- *    Date.new(2001,2,3) <=> Date.new(2001,2,3)   #=> 0
- *    Date.new(2001,2,3) <=> Date.new(2001,2,2)   #=> 1
- *    Date.new(2001,2,3) <=> Object.new           #=> nil
- *    Date.new(2001,2,3) <=> Rational(4903887,2)  #=> 0
+ *     d <=> Object.new # => nil
  *
- * See also Comparable.
  */
 static VALUE
 d_lite_cmp(VALUE self, VALUE other)
@@ -6592,20 +6880,39 @@ equal_gen(VALUE self, VALUE other)
 
 /*
  * call-seq:
- *    d === other  ->  bool
- *
- * Returns true if they are the same day.
- *
- *    Date.new(2001,2,3) === Date.new(2001,2,3)
- * 					#=> true
- *    Date.new(2001,2,3) === Date.new(2001,2,4)
- *					#=> false
- *    DateTime.new(2001,2,3) === DateTime.new(2001,2,3,12)
- *					#=> true
- *    DateTime.new(2001,2,3) === DateTime.new(2001,2,3,0,0,0,'+24:00')
- *					#=> true
- *    DateTime.new(2001,2,3) === DateTime.new(2001,2,4,0,0,0,'+24:00')
- *					#=> false
+ *   self === other -> true, false, or nil.
+ *
+ * Returns +true+ if +self+ and +other+ represent the same date,
+ * +false+ if not, +nil+ if the two are not comparable.
+ *
+ * Argument +other+ may be:
+ *
+ * - Another \Date object:
+ *
+ *     d = Date.new(2022, 7, 27) # => #<Date: 2022-07-27 ((2459788j,0s,0n),+0s,2299161j)>
+ *     prev_date = d.prev_day    # => #<Date: 2022-07-26 ((2459787j,0s,0n),+0s,2299161j)>
+ *     next_date = d.next_day    # => #<Date: 2022-07-28 ((2459789j,0s,0n),+0s,2299161j)>
+ *     d === prev_date           # => false
+ *     d === d                   # => true
+ *     d === next_date           # => false
+ *
+ * - A DateTime object:
+ *
+ *     d === DateTime.new(2022, 7, 26) # => false
+ *     d === DateTime.new(2022, 7, 27) # => true
+ *     d === DateTime.new(2022, 7, 28) # => false
+ *
+ * - A numeric (compares <tt>self.jd</tt> to +other+):
+ *
+ *     d === 2459788 # => true
+ *     d === 2459787 # => false
+ *     d === 2459786 # => false
+ *     d === d.jd    # => true
+ *
+ * - An object not comparable:
+ *
+ *     d === Object.new # => nil
+ *
  */
 static VALUE
 d_lite_equal(VALUE self, VALUE other)
@@ -6668,12 +6975,14 @@ static VALUE strftimev(const char *, VALUE,
 
 /*
  * call-seq:
- *    d.to_s  ->  string
+ *   to_s -> string
  *
- * Returns a string in an ISO 8601 format. (This method doesn't use the
- * expanded representations.)
+ * Returns a string representation of the date in +self+
+ * in {ISO 8601 extended date format}[rdoc-ref:strftime_formatting.rdoc@ISO+8601+Format+Specifications]
+ * (<tt>'%Y-%m-%d'</tt>):
+ *
+ *   Date.new(2001, 2, 3).to_s # => "2001-02-03"
  *
- *     Date.new(2001,2,3).to_s	#=> "2001-02-03"
  */
 static VALUE
 d_lite_to_s(VALUE self)
@@ -6682,6 +6991,7 @@ d_lite_to_s(VALUE self)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 mk_inspect_raw(union DateData *x, VALUE klass)
 {
@@ -6731,6 +7041,7 @@ mk_inspect_raw(union DateData *x, VALUE klass)
     }
 }
 
+/* :nodoc: */
 static VALUE
 d_lite_inspect_raw(VALUE self)
 {
@@ -6752,14 +7063,13 @@ mk_inspect(union DateData *x, VALUE klass, VALUE to_s)
 
 /*
  * call-seq:
- *    d.inspect  ->  string
+ *   inspect -> string
  *
- * Returns the value as a string for inspection.
+ * Returns a string representation of +self+:
+ *
+ *   Date.new(2001, 2, 3).inspect
+ *   # => "#<Date: 2001-02-03 ((2451944j,0s,0n),+0s,2299161j)>"
  *
- *    Date.new(2001,2,3).inspect
- *		#=> "#<Date: 2001-02-03>"
- *    DateTime.new(2001,2,3,4,5,6,'-7').inspect
- *		#=> "#<DateTime: 2001-02-03T04:05:06-07:00>"
  */
 static VALUE
 d_lite_inspect(VALUE self)
@@ -6941,180 +7251,16 @@ date_strftime_internal(int argc, VALUE *argv, VALUE self,
 
 /*
  * call-seq:
- *    d.strftime([format='%F'])  ->  string
- *
- * Formats date according to the directives in the given format
- * string.
- * The directives begin with a percent (%) character.
- * Any text not listed as a directive will be passed through to the
- * output string.
- *
- * A directive consists of a percent (%) character,
- * zero or more flags, an optional minimum field width,
- * an optional modifier, and a conversion specifier
- * as follows.
- *
- *    %<flags><width><modifier><conversion>
- *
- * Flags:
- *    -  don't pad a numerical output.
- *    _  use spaces for padding.
- *    0  use zeros for padding.
- *    ^  upcase the result string.
- *    #  change case.
- *
- * The minimum field width specifies the minimum width.
- *
- * The modifiers are "E", "O", ":", "::" and ":::".
- * "E" and "O" are ignored.  No effect to result currently.
- *
- * Format directives:
- *
- *    Date (Year, Month, Day):
- *      %Y - Year with century (can be negative, 4 digits at least)
- *              -0001, 0000, 1995, 2009, 14292, etc.
- *      %C - year / 100 (round down.  20 in 2009)
- *      %y - year % 100 (00..99)
- *
- *      %m - Month of the year, zero-padded (01..12)
- *              %_m  blank-padded ( 1..12)
- *              %-m  no-padded (1..12)
- *      %B - The full month name (``January'')
- *              %^B  uppercased (``JANUARY'')
- *      %b - The abbreviated month name (``Jan'')
- *              %^b  uppercased (``JAN'')
- *      %h - Equivalent to %b
- *
- *      %d - Day of the month, zero-padded (01..31)
- *              %-d  no-padded (1..31)
- *      %e - Day of the month, blank-padded ( 1..31)
- *
- *      %j - Day of the year (001..366)
- *
- *    Time (Hour, Minute, Second, Subsecond):
- *      %H - Hour of the day, 24-hour clock, zero-padded (00..23)
- *      %k - Hour of the day, 24-hour clock, blank-padded ( 0..23)
- *      %I - Hour of the day, 12-hour clock, zero-padded (01..12)
- *      %l - Hour of the day, 12-hour clock, blank-padded ( 1..12)
- *      %P - Meridian indicator, lowercase (``am'' or ``pm'')
- *      %p - Meridian indicator, uppercase (``AM'' or ``PM'')
- *
- *      %M - Minute of the hour (00..59)
- *
- *      %S - Second of the minute (00..60)
- *
- *      %L - Millisecond of the second (000..999)
- *      %N - Fractional seconds digits, default is 9 digits (nanosecond)
- *              %3N  millisecond (3 digits)   %15N femtosecond (15 digits)
- *              %6N  microsecond (6 digits)   %18N attosecond  (18 digits)
- *              %9N  nanosecond  (9 digits)   %21N zeptosecond (21 digits)
- *              %12N picosecond (12 digits)   %24N yoctosecond (24 digits)
- *
- *    Time zone:
- *      %z - Time zone as hour and minute offset from UTC (e.g. +0900)
- *              %:z - hour and minute offset from UTC with a colon (e.g. +09:00)
- *              %::z - hour, minute and second offset from UTC (e.g. +09:00:00)
- *              %:::z - hour, minute and second offset from UTC
- *                                                (e.g. +09, +09:30, +09:30:30)
- *      %Z - Equivalent to %:z (e.g. +09:00)
- *
- *    Weekday:
- *      %A - The full weekday name (``Sunday'')
- *              %^A  uppercased (``SUNDAY'')
- *      %a - The abbreviated name (``Sun'')
- *              %^a  uppercased (``SUN'')
- *      %u - Day of the week (Monday is 1, 1..7)
- *      %w - Day of the week (Sunday is 0, 0..6)
- *
- *    ISO 8601 week-based year and week number:
- *    The week 1 of YYYY starts with a Monday and includes YYYY-01-04.
- *    The days in the year before the first week are in the last week of
- *    the previous year.
- *      %G - The week-based year
- *      %g - The last 2 digits of the week-based year (00..99)
- *      %V - Week number of the week-based year (01..53)
- *
- *    Week number:
- *    The week 1 of YYYY starts with a Sunday or Monday (according to %U
- *    or %W).  The days in the year before the first week are in week 0.
- *      %U - Week number of the year.  The week starts with Sunday.  (00..53)
- *      %W - Week number of the year.  The week starts with Monday.  (00..53)
- *
- *    Seconds since the Unix Epoch:
- *      %s - Number of seconds since 1970-01-01 00:00:00 UTC.
- *      %Q - Number of milliseconds since 1970-01-01 00:00:00 UTC.
- *
- *    Literal string:
- *      %n - Newline character (\n)
- *      %t - Tab character (\t)
- *      %% - Literal ``%'' character
- *
- *    Combination:
- *      %c - date and time (%a %b %e %T %Y)
- *      %D - Date (%m/%d/%y)
- *      %F - The ISO 8601 date format (%Y-%m-%d)
- *      %v - VMS date (%e-%^b-%Y)
- *      %x - Same as %D
- *      %X - Same as %T
- *      %r - 12-hour time (%I:%M:%S %p)
- *      %R - 24-hour time (%H:%M)
- *      %T - 24-hour time (%H:%M:%S)
- *      %+ - date(1) (%a %b %e %H:%M:%S %Z %Y)
- *
- * This method is similar to the strftime() function defined in ISO C
- * and POSIX.
- * Several directives (%a, %A, %b, %B, %c, %p, %r, %x, %X, %E*, %O* and %Z)
- * are locale dependent in the function.
- * However, this method is locale independent.
- * So, the result may differ even if the same format string is used in other
- * systems such as C.
- * It is good practice to avoid %x and %X because there are corresponding
- * locale independent representations, %D and %T.
- *
- * Examples:
- *
- *    d = DateTime.new(2007,11,19,8,37,48,"-06:00")
- *				#=> #<DateTime: 2007-11-19T08:37:48-0600 ...>
- *    d.strftime("Printed on %m/%d/%Y")   #=> "Printed on 11/19/2007"
- *    d.strftime("at %I:%M%p")            #=> "at 08:37AM"
- *
- * Various ISO 8601 formats:
- *    %Y%m%d           => 20071119                  Calendar date (basic)
- *    %F               => 2007-11-19                Calendar date (extended)
- *    %Y-%m            => 2007-11                   Calendar date, reduced accuracy, specific month
- *    %Y               => 2007                      Calendar date, reduced accuracy, specific year
- *    %C               => 20                        Calendar date, reduced accuracy, specific century
- *    %Y%j             => 2007323                   Ordinal date (basic)
- *    %Y-%j            => 2007-323                  Ordinal date (extended)
- *    %GW%V%u          => 2007W471                  Week date (basic)
- *    %G-W%V-%u        => 2007-W47-1                Week date (extended)
- *    %GW%V            => 2007W47                   Week date, reduced accuracy, specific week (basic)
- *    %G-W%V           => 2007-W47                  Week date, reduced accuracy, specific week (extended)
- *    %H%M%S           => 083748                    Local time (basic)
- *    %T               => 08:37:48                  Local time (extended)
- *    %H%M             => 0837                      Local time, reduced accuracy, specific minute (basic)
- *    %H:%M            => 08:37                     Local time, reduced accuracy, specific minute (extended)
- *    %H               => 08                        Local time, reduced accuracy, specific hour
- *    %H%M%S,%L        => 083748,000                Local time with decimal fraction, comma as decimal sign (basic)
- *    %T,%L            => 08:37:48,000              Local time with decimal fraction, comma as decimal sign (extended)
- *    %H%M%S.%L        => 083748.000                Local time with decimal fraction, full stop as decimal sign (basic)
- *    %T.%L            => 08:37:48.000              Local time with decimal fraction, full stop as decimal sign (extended)
- *    %H%M%S%z         => 083748-0600               Local time and the difference from UTC (basic)
- *    %T%:z            => 08:37:48-06:00            Local time and the difference from UTC (extended)
- *    %Y%m%dT%H%M%S%z  => 20071119T083748-0600      Date and time of day for calendar date (basic)
- *    %FT%T%:z         => 2007-11-19T08:37:48-06:00 Date and time of day for calendar date (extended)
- *    %Y%jT%H%M%S%z    => 2007323T083748-0600       Date and time of day for ordinal date (basic)
- *    %Y-%jT%T%:z      => 2007-323T08:37:48-06:00   Date and time of day for ordinal date (extended)
- *    %GW%V%uT%H%M%S%z => 2007W471T083748-0600      Date and time of day for week date (basic)
- *    %G-W%V-%uT%T%:z  => 2007-W47-1T08:37:48-06:00 Date and time of day for week date (extended)
- *    %Y%m%dT%H%M      => 20071119T0837             Calendar date and local time (basic)
- *    %FT%R            => 2007-11-19T08:37          Calendar date and local time (extended)
- *    %Y%jT%H%MZ       => 2007323T0837Z             Ordinal date and UTC of day (basic)
- *    %Y-%jT%RZ        => 2007-323T08:37Z           Ordinal date and UTC of day (extended)
- *    %GW%V%uT%H%M%z   => 2007W471T0837-0600        Week date and local time and difference from UTC (basic)
- *    %G-W%V-%uT%R%:z  => 2007-W47-1T08:37-06:00    Week date and local time and difference from UTC (extended)
- *
- * See also strftime(3) and ::strptime.
+ *   strftime(format = '%F') -> string
+ *
+ * Returns a string representation of the date in +self+,
+ * formatted according the given +format+:
+ *
+ *   Date.new(2001, 2, 3).strftime # => "2001-02-03"
+ *
+ * For other formats, see
+ * {Formats for Dates and Times}[rdoc-ref:strftime_formatting.rdoc].
+ *
  */
 static VALUE
 d_lite_strftime(int argc, VALUE *argv, VALUE self)
@@ -7142,13 +7288,17 @@ strftimev(const char *fmt, VALUE self,
 
 /*
  * call-seq:
- *    d.asctime  ->  string
- *    d.ctime    ->  string
+ *   asctime -> string
  *
- * Returns a string in asctime(3) format (but without "\n\0" at the
- * end).  This method is equivalent to strftime('%c').
+ * Equivalent to #strftime with argument <tt>'%a %b %e %T %Y'</tt>
+ * (or its {shorthand form}[rdoc-ref:strftime_formatting.rdoc@Shorthand+Conversion+Specifiers]
+ * <tt>'%c'</tt>):
  *
- * See also asctime(3) or ctime(3).
+ *   Date.new(2001, 2, 3).asctime # => "Sat Feb  3 00:00:00 2001"
+ *
+ * See {asctime}[https://linux.die.net/man/3/asctime].
+ *
+ * Date#ctime is an alias for Date#asctime.
  */
 static VALUE
 d_lite_asctime(VALUE self)
@@ -7158,10 +7308,15 @@ d_lite_asctime(VALUE self)
 
 /*
  * call-seq:
- *    d.iso8601    ->  string
- *    d.xmlschema  ->  string
+ *   iso8601    ->  string
+ *
+ * Equivalent to #strftime with argument <tt>'%Y-%m-%d'</tt>
+ * (or its {shorthand form}[rdoc-ref:strftime_formatting.rdoc@Shorthand+Conversion+Specifiers]
+ * <tt>'%F'</tt>);
  *
- * This method is equivalent to strftime('%F').
+ *   Date.new(2001, 2, 3).iso8601 # => "2001-02-03"
+ *
+ * Date#xmlschema is an alias for Date#iso8601.
  */
 static VALUE
 d_lite_iso8601(VALUE self)
@@ -7171,9 +7326,13 @@ d_lite_iso8601(VALUE self)
 
 /*
  * call-seq:
- *    d.rfc3339  ->  string
+ *   rfc3339 -> string
+ *
+ * Equivalent to #strftime with argument <tt>'%FT%T%:z'</tt>;
+ * see {Formats for Dates and Times}[rdoc-ref:strftime_formatting.rdoc]:
+ *
+ *   Date.new(2001, 2, 3).rfc3339 # => "2001-02-03T00:00:00+00:00"
  *
- * This method is equivalent to strftime('%FT%T%:z').
  */
 static VALUE
 d_lite_rfc3339(VALUE self)
@@ -7183,10 +7342,14 @@ d_lite_rfc3339(VALUE self)
 
 /*
  * call-seq:
- *    d.rfc2822  ->  string
- *    d.rfc822   ->  string
+ *   rfc2822 -> string
+ *
+ * Equivalent to #strftime with argument <tt>'%a, %-d %b %Y %T %z'</tt>;
+ * see {Formats for Dates and Times}[rdoc-ref:strftime_formatting.rdoc]:
  *
- * This method is equivalent to strftime('%a, %-d %b %Y %T %z').
+ *   Date.new(2001, 2, 3).rfc2822 # => "Sat, 3 Feb 2001 00:00:00 +0000"
+ *
+ * Date#rfc822 is an alias for Date#rfc2822.
  */
 static VALUE
 d_lite_rfc2822(VALUE self)
@@ -7196,10 +7359,13 @@ d_lite_rfc2822(VALUE self)
 
 /*
  * call-seq:
- *    d.httpdate  ->  string
+ *   httpdate -> string
+ *
+ * Equivalent to #strftime with argument <tt>'%a, %d %b %Y %T GMT'</tt>;
+ * see {Formats for Dates and Times}[rdoc-ref:strftime_formatting.rdoc]:
+ *
+ *   Date.new(2001, 2, 3).httpdate # => "Sat, 03 Feb 2001 00:00:00 GMT"
  *
- * This method is equivalent to strftime('%a, %d %b %Y %T GMT').
- * See also RFC 2616.
  */
 static VALUE
 d_lite_httpdate(VALUE self)
@@ -7250,11 +7416,13 @@ jisx0301_date_format(char *fmt, size_t size, VALUE jd, VALUE y)
 
 /*
  * call-seq:
- *    d.jisx0301  ->  string
+ *   jisx0301 -> string
  *
- * Returns a string in a JIS X 0301 format.
+ * Returns a string representation of the date in +self+
+ * in JIS X 0301 format.
+ *
+ *   Date.new(2001, 2, 3).jisx0301 # => "H13.02.03"
  *
- *    Date.new(2001,2,3).jisx0301	#=> "H13.02.03"
  */
 static VALUE
 d_lite_jisx0301(VALUE self)
@@ -7269,7 +7437,98 @@ d_lite_jisx0301(VALUE self)
     return strftimev(fmt, self, set_tmx);
 }
 
+static VALUE
+deconstruct_keys(VALUE self, VALUE keys, int is_datetime)
+{
+    VALUE h = rb_hash_new();
+    long i;
+
+    get_d1(self);
+
+    if (NIL_P(keys)) {
+        rb_hash_aset(h, sym_year, m_real_year(dat));
+        rb_hash_aset(h, sym_month, INT2FIX(m_mon(dat)));
+        rb_hash_aset(h, sym_day, INT2FIX(m_mday(dat)));
+        rb_hash_aset(h, sym_yday, INT2FIX(m_yday(dat)));
+        rb_hash_aset(h, sym_wday, INT2FIX(m_wday(dat)));
+        if (is_datetime) {
+            rb_hash_aset(h, sym_hour, INT2FIX(m_hour(dat)));
+            rb_hash_aset(h, sym_min, INT2FIX(m_min(dat)));
+            rb_hash_aset(h, sym_sec, INT2FIX(m_sec(dat)));
+            rb_hash_aset(h, sym_sec_fraction, m_sf_in_sec(dat));
+            rb_hash_aset(h, sym_zone, m_zone(dat));
+        }
+
+        return h;
+    }
+    if (!RB_TYPE_P(keys, T_ARRAY)) {
+        rb_raise(rb_eTypeError,
+                 "wrong argument type %"PRIsVALUE" (expected Array or nil)",
+                 rb_obj_class(keys));
+
+    }
+
+    for (i=0; i<RARRAY_LEN(keys); i++) {
+        VALUE key = RARRAY_AREF(keys, i);
+
+        if (sym_year == key) rb_hash_aset(h, key, m_real_year(dat));
+        if (sym_month == key) rb_hash_aset(h, key, INT2FIX(m_mon(dat)));
+        if (sym_day == key) rb_hash_aset(h, key, INT2FIX(m_mday(dat)));
+        if (sym_yday == key) rb_hash_aset(h, key, INT2FIX(m_yday(dat)));
+        if (sym_wday == key) rb_hash_aset(h, key, INT2FIX(m_wday(dat)));
+        if (is_datetime) {
+            if (sym_hour == key) rb_hash_aset(h, key, INT2FIX(m_hour(dat)));
+            if (sym_min == key) rb_hash_aset(h, key, INT2FIX(m_min(dat)));
+            if (sym_sec == key) rb_hash_aset(h, key, INT2FIX(m_sec(dat)));
+            if (sym_sec_fraction == key) rb_hash_aset(h, key, m_sf_in_sec(dat));
+            if (sym_zone == key) rb_hash_aset(h, key, m_zone(dat));
+        }
+    }
+    return h;
+}
+
+/*
+ *  call-seq:
+ *    deconstruct_keys(array_of_names_or_nil) -> hash
+ *
+ *  Returns a hash of the name/value pairs, to use in pattern matching.
+ *  Possible keys are: <tt>:year</tt>, <tt>:month</tt>, <tt>:day</tt>,
+ *  <tt>:wday</tt>, <tt>:yday</tt>.
+ *
+ *  Possible usages:
+ *
+ *    d = Date.new(2022, 10, 5)
+ *
+ *    if d in wday: 3, day: ..7  # uses deconstruct_keys underneath
+ *      puts "first Wednesday of the month"
+ *    end
+ *    #=> prints "first Wednesday of the month"
+ *
+ *    case d
+ *    in year: ...2022
+ *      puts "too old"
+ *    in month: ..9
+ *      puts "quarter 1-3"
+ *    in wday: 1..5, month:
+ *      puts "working day in month #{month}"
+ *    end
+ *    #=> prints "working day in month 10"
+ *
+ *  Note that deconstruction by pattern can also be combined with class check:
+ *
+ *    if d in Date(wday: 3, day: ..7)
+ *      puts "first Wednesday of the month"
+ *    end
+ *
+ */
+static VALUE
+d_lite_deconstruct_keys(VALUE self, VALUE keys)
+{
+    return deconstruct_keys(self, keys, /* is_datetime=false */ 0);
+}
+
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 d_lite_marshal_dump_old(VALUE self)
 {
@@ -7557,17 +7816,7 @@ datetime_s_ordinal(int argc, VALUE *argv, VALUE klass)
 }
 
 /*
- * call-seq:
- *    DateTime.civil([year=-4712[, month=1[, mday=1[, hour=0[, minute=0[, second=0[, offset=0[, start=Date::ITALY]]]]]]]])  ->  datetime
- *    DateTime.new([year=-4712[, month=1[, mday=1[, hour=0[, minute=0[, second=0[, offset=0[, start=Date::ITALY]]]]]]]])    ->  datetime
- *
- * Creates a DateTime object denoting the given calendar date.
- *
- *    DateTime.new(2001,2,3)	#=> #<DateTime: 2001-02-03T00:00:00+00:00 ...>
- *    DateTime.new(2001,2,3,4,5,6,'+7')
- *				#=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
- *    DateTime.new(2001,-11,-26,-20,-55,-54,'+7')
- *				#=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
+ * Same as DateTime.new.
  */
 static VALUE
 datetime_s_civil(int argc, VALUE *argv, VALUE klass)
@@ -7757,6 +8006,7 @@ datetime_s_commercial(int argc, VALUE *argv, VALUE klass)
 }
 
 #ifndef NDEBUG
+/* :nodoc: */
 static VALUE
 datetime_s_weeknum(int argc, VALUE *argv, VALUE klass)
 {
@@ -7826,6 +8076,7 @@ datetime_s_weeknum(int argc, VALUE *argv, VALUE klass)
     return ret;
 }
 
+/* :nodoc: */
 static VALUE
 datetime_s_nth_kday(int argc, VALUE *argv, VALUE klass)
 {
@@ -8171,9 +8422,9 @@ datetime_s_strptime(int argc, VALUE *argv, VALUE klass)
  * Parses the given representation of date and time, and creates a
  * DateTime object.
  *
- * This method *does not* function as a validator.  If the input
+ * This method *does* *not* function as a validator.  If the input
  * string does not match valid formats strictly, you may get a cryptic
- * result.  Should consider to use `DateTime.strptime` instead of this
+ * result.  Should consider to use DateTime.strptime instead of this
  * method as possible.
  *
  * If the optional second argument is true and the detected year is in
@@ -8187,8 +8438,8 @@ datetime_s_strptime(int argc, VALUE *argv, VALUE klass)
  *				#=> #<DateTime: 2001-02-03T16:05:06+00:00 ...>
  *
  * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ * You can stop this check by passing <code>limit: nil</code>, but note
+ * that it may take a long time to parse.
  */
 static VALUE
 datetime_s_parse(int argc, VALUE *argv, VALUE klass)
@@ -8234,8 +8485,8 @@ datetime_s_parse(int argc, VALUE *argv, VALUE klass)
  *				#=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
  *
  * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ * You can stop this check by passing <code>limit: nil</code>, but note
+ * that it may take a long time to parse.
  */
 static VALUE
 datetime_s_iso8601(int argc, VALUE *argv, VALUE klass)
@@ -8274,8 +8525,8 @@ datetime_s_iso8601(int argc, VALUE *argv, VALUE klass)
  *				#=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
  *
  * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ * You can stop this check by passing <code>limit: nil</code>, but note
+ * that it may take a long time to parse.
  */
 static VALUE
 datetime_s_rfc3339(int argc, VALUE *argv, VALUE klass)
@@ -8314,8 +8565,8 @@ datetime_s_rfc3339(int argc, VALUE *argv, VALUE klass)
  *				#=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
  *
  * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ * You can stop this check by passing <code>limit: nil</code>, but note
+ * that it may take a long time to parse.
  */
 static VALUE
 datetime_s_xmlschema(int argc, VALUE *argv, VALUE klass)
@@ -8355,8 +8606,8 @@ datetime_s_xmlschema(int argc, VALUE *argv, VALUE klass)
  *				#=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
  *
  * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ * You can stop this check by passing <code>limit: nil</code>, but note
+ * that it may take a long time to parse.
  */
 static VALUE
 datetime_s_rfc2822(int argc, VALUE *argv, VALUE klass)
@@ -8395,8 +8646,8 @@ datetime_s_rfc2822(int argc, VALUE *argv, VALUE klass)
  *				#=> #<DateTime: 2001-02-03T04:05:06+00:00 ...>
  *
  * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ * You can stop this check by passing <code>limit: nil</code>, but note
+ * that it may take a long time to parse.
  */
 static VALUE
 datetime_s_httpdate(int argc, VALUE *argv, VALUE klass)
@@ -8440,8 +8691,8 @@ datetime_s_httpdate(int argc, VALUE *argv, VALUE klass)
  *				#=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
  *
  * Raise an ArgumentError when the string length is longer than _limit_.
- * You can stop this check by passing `limit: nil`, but note that
- * it may take a long time to parse.
+ * You can stop this check by passing <code>limit: nil</code>, but note
+ * that it may take a long time to parse.
  */
 static VALUE
 datetime_s_jisx0301(int argc, VALUE *argv, VALUE klass)
@@ -8487,181 +8738,16 @@ dt_lite_to_s(VALUE self)
 
 /*
  * call-seq:
- *    dt.strftime([format='%FT%T%:z'])  ->  string
- *
- * Formats date according to the directives in the given format
- * string.
- * The directives begin with a percent (%) character.
- * Any text not listed as a directive will be passed through to the
- * output string.
- *
- * A directive consists of a percent (%) character,
- * zero or more flags, an optional minimum field width,
- * an optional modifier, and a conversion specifier
- * as follows.
- *
- *    %<flags><width><modifier><conversion>
- *
- * Flags:
- *    -  don't pad a numerical output.
- *    _  use spaces for padding.
- *    0  use zeros for padding.
- *    ^  upcase the result string.
- *    #  change case.
- *    :  use colons for %z.
- *
- * The minimum field width specifies the minimum width.
- *
- * The modifiers are "E" and "O".
- * They are ignored.
- *
- * Format directives:
- *
- *    Date (Year, Month, Day):
- *      %Y - Year with century (can be negative, 4 digits at least)
- *              -0001, 0000, 1995, 2009, 14292, etc.
- *      %C - year / 100 (round down.  20 in 2009)
- *      %y - year % 100 (00..99)
- *
- *      %m - Month of the year, zero-padded (01..12)
- *              %_m  blank-padded ( 1..12)
- *              %-m  no-padded (1..12)
- *      %B - The full month name (``January'')
- *              %^B  uppercased (``JANUARY'')
- *      %b - The abbreviated month name (``Jan'')
- *              %^b  uppercased (``JAN'')
- *      %h - Equivalent to %b
- *
- *      %d - Day of the month, zero-padded (01..31)
- *              %-d  no-padded (1..31)
- *      %e - Day of the month, blank-padded ( 1..31)
- *
- *      %j - Day of the year (001..366)
- *
- *    Time (Hour, Minute, Second, Subsecond):
- *      %H - Hour of the day, 24-hour clock, zero-padded (00..23)
- *      %k - Hour of the day, 24-hour clock, blank-padded ( 0..23)
- *      %I - Hour of the day, 12-hour clock, zero-padded (01..12)
- *      %l - Hour of the day, 12-hour clock, blank-padded ( 1..12)
- *      %P - Meridian indicator, lowercase (``am'' or ``pm'')
- *      %p - Meridian indicator, uppercase (``AM'' or ``PM'')
- *
- *      %M - Minute of the hour (00..59)
- *
- *      %S - Second of the minute (00..60)
- *
- *      %L - Millisecond of the second (000..999)
- *      %N - Fractional seconds digits, default is 9 digits (nanosecond)
- *              %3N  millisecond (3 digits)   %15N femtosecond (15 digits)
- *              %6N  microsecond (6 digits)   %18N attosecond  (18 digits)
- *              %9N  nanosecond  (9 digits)   %21N zeptosecond (21 digits)
- *              %12N picosecond (12 digits)   %24N yoctosecond (24 digits)
- *
- *    Time zone:
- *      %z - Time zone as hour and minute offset from UTC (e.g. +0900)
- *              %:z - hour and minute offset from UTC with a colon (e.g. +09:00)
- *              %::z - hour, minute and second offset from UTC (e.g. +09:00:00)
- *              %:::z - hour, minute and second offset from UTC
- *                                                (e.g. +09, +09:30, +09:30:30)
- *      %Z - Equivalent to %:z (e.g. +09:00)
- *
- *    Weekday:
- *      %A - The full weekday name (``Sunday'')
- *              %^A  uppercased (``SUNDAY'')
- *      %a - The abbreviated name (``Sun'')
- *              %^a  uppercased (``SUN'')
- *      %u - Day of the week (Monday is 1, 1..7)
- *      %w - Day of the week (Sunday is 0, 0..6)
- *
- *    ISO 8601 week-based year and week number:
- *    The week 1 of YYYY starts with a Monday and includes YYYY-01-04.
- *    The days in the year before the first week are in the last week of
- *    the previous year.
- *      %G - The week-based year
- *      %g - The last 2 digits of the week-based year (00..99)
- *      %V - Week number of the week-based year (01..53)
- *
- *    Week number:
- *    The week 1 of YYYY starts with a Sunday or Monday (according to %U
- *    or %W).  The days in the year before the first week are in week 0.
- *      %U - Week number of the year.  The week starts with Sunday.  (00..53)
- *      %W - Week number of the year.  The week starts with Monday.  (00..53)
- *
- *    Seconds since the Unix Epoch:
- *      %s - Number of seconds since 1970-01-01 00:00:00 UTC.
- *      %Q - Number of milliseconds since 1970-01-01 00:00:00 UTC.
- *
- *    Literal string:
- *      %n - Newline character (\n)
- *      %t - Tab character (\t)
- *      %% - Literal ``%'' character
- *
- *    Combination:
- *      %c - date and time (%a %b %e %T %Y)
- *      %D - Date (%m/%d/%y)
- *      %F - The ISO 8601 date format (%Y-%m-%d)
- *      %v - VMS date (%e-%^b-%Y)
- *      %x - Same as %D
- *      %X - Same as %T
- *      %r - 12-hour time (%I:%M:%S %p)
- *      %R - 24-hour time (%H:%M)
- *      %T - 24-hour time (%H:%M:%S)
- *      %+ - date(1) (%a %b %e %H:%M:%S %Z %Y)
- *
- * This method is similar to the strftime() function defined in ISO C
- * and POSIX.
- * Several directives (%a, %A, %b, %B, %c, %p, %r, %x, %X, %E*, %O* and %Z)
- * are locale dependent in the function.
- * However, this method is locale independent.
- * So, the result may differ even if the same format string is used in other
- * systems such as C.
- * It is good practice to avoid %x and %X because there are corresponding
- * locale independent representations, %D and %T.
- *
- * Examples:
- *
- *    d = DateTime.new(2007,11,19,8,37,48,"-06:00")
- *				#=> #<DateTime: 2007-11-19T08:37:48-0600 ...>
- *    d.strftime("Printed on %m/%d/%Y")   #=> "Printed on 11/19/2007"
- *    d.strftime("at %I:%M%p")            #=> "at 08:37AM"
- *
- * Various ISO 8601 formats:
- *    %Y%m%d           => 20071119                  Calendar date (basic)
- *    %F               => 2007-11-19                Calendar date (extended)
- *    %Y-%m            => 2007-11                   Calendar date, reduced accuracy, specific month
- *    %Y               => 2007                      Calendar date, reduced accuracy, specific year
- *    %C               => 20                        Calendar date, reduced accuracy, specific century
- *    %Y%j             => 2007323                   Ordinal date (basic)
- *    %Y-%j            => 2007-323                  Ordinal date (extended)
- *    %GW%V%u          => 2007W471                  Week date (basic)
- *    %G-W%V-%u        => 2007-W47-1                Week date (extended)
- *    %GW%V            => 2007W47                   Week date, reduced accuracy, specific week (basic)
- *    %G-W%V           => 2007-W47                  Week date, reduced accuracy, specific week (extended)
- *    %H%M%S           => 083748                    Local time (basic)
- *    %T               => 08:37:48                  Local time (extended)
- *    %H%M             => 0837                      Local time, reduced accuracy, specific minute (basic)
- *    %H:%M            => 08:37                     Local time, reduced accuracy, specific minute (extended)
- *    %H               => 08                        Local time, reduced accuracy, specific hour
- *    %H%M%S,%L        => 083748,000                Local time with decimal fraction, comma as decimal sign (basic)
- *    %T,%L            => 08:37:48,000              Local time with decimal fraction, comma as decimal sign (extended)
- *    %H%M%S.%L        => 083748.000                Local time with decimal fraction, full stop as decimal sign (basic)
- *    %T.%L            => 08:37:48.000              Local time with decimal fraction, full stop as decimal sign (extended)
- *    %H%M%S%z         => 083748-0600               Local time and the difference from UTC (basic)
- *    %T%:z            => 08:37:48-06:00            Local time and the difference from UTC (extended)
- *    %Y%m%dT%H%M%S%z  => 20071119T083748-0600      Date and time of day for calendar date (basic)
- *    %FT%T%:z         => 2007-11-19T08:37:48-06:00 Date and time of day for calendar date (extended)
- *    %Y%jT%H%M%S%z    => 2007323T083748-0600       Date and time of day for ordinal date (basic)
- *    %Y-%jT%T%:z      => 2007-323T08:37:48-06:00   Date and time of day for ordinal date (extended)
- *    %GW%V%uT%H%M%S%z => 2007W471T083748-0600      Date and time of day for week date (basic)
- *    %G-W%V-%uT%T%:z  => 2007-W47-1T08:37:48-06:00 Date and time of day for week date (extended)
- *    %Y%m%dT%H%M      => 20071119T0837             Calendar date and local time (basic)
- *    %FT%R            => 2007-11-19T08:37          Calendar date and local time (extended)
- *    %Y%jT%H%MZ       => 2007323T0837Z             Ordinal date and UTC of day (basic)
- *    %Y-%jT%RZ        => 2007-323T08:37Z           Ordinal date and UTC of day (extended)
- *    %GW%V%uT%H%M%z   => 2007W471T0837-0600        Week date and local time and difference from UTC (basic)
- *    %G-W%V-%uT%R%:z  => 2007-W47-1T08:37-06:00    Week date and local time and difference from UTC (extended)
- *
- * See also strftime(3) and ::strptime.
+ *   strftime(format = '%FT%T%:z') -> string
+ *
+ * Returns a string representation of +self+,
+ * formatted according the given +format:
+ *
+ *   DateTime.now.strftime # => "2022-07-01T11:03:19-05:00"
+ *
+ * For other formats, see
+ * {Formats for Dates and Times}[doc/strftime_formatting.rdoc].
+ *
  */
 static VALUE
 dt_lite_strftime(int argc, VALUE *argv, VALUE self)
@@ -8749,6 +8835,47 @@ dt_lite_jisx0301(int argc, VALUE *argv, VALUE self)
 			 iso8601_timediv(self, n));
 }
 
+/*
+ *  call-seq:
+ *    deconstruct_keys(array_of_names_or_nil) -> hash
+ *
+ *  Returns a hash of the name/value pairs, to use in pattern matching.
+ *  Possible keys are: <tt>:year</tt>, <tt>:month</tt>, <tt>:day</tt>,
+ *  <tt>:wday</tt>, <tt>:yday</tt>, <tt>:hour</tt>, <tt>:min</tt>,
+ *  <tt>:sec</tt>, <tt>:sec_fraction</tt>, <tt>:zone</tt>.
+ *
+ *  Possible usages:
+ *
+ *    dt = DateTime.new(2022, 10, 5, 13, 30)
+ *
+ *    if d in wday: 1..5, hour: 10..18  # uses deconstruct_keys underneath
+ *      puts "Working time"
+ *    end
+ *    #=> prints "Working time"
+ *
+ *    case dt
+ *    in year: ...2022
+ *      puts "too old"
+ *    in month: ..9
+ *      puts "quarter 1-3"
+ *    in wday: 1..5, month:
+ *      puts "working day in month #{month}"
+ *    end
+ *    #=> prints "working day in month 10"
+ *
+ *  Note that deconstruction by pattern can also be combined with class check:
+ *
+ *    if d in DateTime(wday: 1..5, hour: 10..18, day: ..7)
+ *      puts "Working time, first week of the month"
+ *    end
+ *
+ */
+static VALUE
+dt_lite_deconstruct_keys(VALUE self, VALUE keys)
+{
+    return deconstruct_keys(self, keys, /* is_datetime=true */ 1);
+}
+
 /* conversions */
 
 #define f_subsec(x) rb_funcall(x, rb_intern("subsec"), 0)
@@ -8827,7 +8954,7 @@ time_to_datetime(VALUE self)
     ret = d_complex_new_internal(cDateTime,
 				 nth, 0,
 				 0, sf,
-				 of, DEFAULT_SG,
+				 of, GREGORIAN,
 				 ry, m, d,
 				 h, min, s,
 				 HAVE_CIVIL | HAVE_TIME);
@@ -8840,10 +8967,15 @@ time_to_datetime(VALUE self)
 
 /*
  * call-seq:
- *    d.to_time  ->  time
+ *   to_time -> time
+ *
+ * Returns a new Time object with the same value as +self+;
+ * if +self+ is a Julian date, derives its Gregorian date
+ * for conversion to the \Time object:
+ *
+ *   Date.new(2001, 2, 3).to_time               # => 2001-02-03 00:00:00 -0600
+ *   Date.new(2001, 2, 3, Date::JULIAN).to_time # => 2001-02-16 00:00:00 -0600
  *
- * Returns a Time object which denotes self. If self is a julian date,
- * convert it to a gregorian date before converting it to Time.
  */
 static VALUE
 date_to_time(VALUE self)
@@ -8864,9 +8996,9 @@ date_to_time(VALUE self)
 
 /*
  * call-seq:
- *    d.to_date  ->  self
+ *   to_date -> self
  *
- * Returns self.
+ * Returns +self+.
  */
 static VALUE
 date_to_date(VALUE self)
@@ -8878,7 +9010,10 @@ date_to_date(VALUE self)
  * call-seq:
  *    d.to_datetime  -> datetime
  *
- * Returns a DateTime object which denotes self.
+ * Returns a DateTime whose value is the same as +self+:
+ *
+ *   Date.new(2001, 2, 3).to_datetime # => #<DateTime: 2001-02-03T00:00:00+00:00>
+ *
  */
 static VALUE
 date_to_datetime(VALUE self)
@@ -8923,12 +9058,17 @@ date_to_datetime(VALUE self)
 static VALUE
 datetime_to_time(VALUE self)
 {
-    volatile VALUE dup = dup_obj(self);
+    get_d1(self);
+
+    if (m_julian_p(dat)) {
+	self = d_lite_gregorian(self);
+	get_d1a(self);
+	dat = adat;
+    }
+
     {
 	VALUE t;
 
-	get_d1(dup);
-
 	t = rb_funcall(rb_cTime,
 		   rb_intern("new"),
                    7,
@@ -8996,6 +9136,7 @@ datetime_to_datetime(VALUE self)
 #define MIN_JD -327
 #define MAX_JD 366963925
 
+/* :nodoc: */
 static int
 test_civil(int from, int to, double sg)
 {
@@ -9016,6 +9157,7 @@ test_civil(int from, int to, double sg)
     return 1;
 }
 
+/* :nodoc: */
 static VALUE
 date_s_test_civil(VALUE klass)
 {
@@ -9036,6 +9178,7 @@ date_s_test_civil(VALUE klass)
     return Qtrue;
 }
 
+/* :nodoc: */
 static int
 test_ordinal(int from, int to, double sg)
 {
@@ -9056,6 +9199,7 @@ test_ordinal(int from, int to, double sg)
     return 1;
 }
 
+/* :nodoc: */
 static VALUE
 date_s_test_ordinal(VALUE klass)
 {
@@ -9076,6 +9220,7 @@ date_s_test_ordinal(VALUE klass)
     return Qtrue;
 }
 
+/* :nodoc: */
 static int
 test_commercial(int from, int to, double sg)
 {
@@ -9096,6 +9241,7 @@ test_commercial(int from, int to, double sg)
     return 1;
 }
 
+/* :nodoc: */
 static VALUE
 date_s_test_commercial(VALUE klass)
 {
@@ -9116,6 +9262,7 @@ date_s_test_commercial(VALUE klass)
     return Qtrue;
 }
 
+/* :nodoc: */
 static int
 test_weeknum(int from, int to, int f, double sg)
 {
@@ -9136,6 +9283,7 @@ test_weeknum(int from, int to, int f, double sg)
     return 1;
 }
 
+/* :nodoc: */
 static VALUE
 date_s_test_weeknum(VALUE klass)
 {
@@ -9160,6 +9308,7 @@ date_s_test_weeknum(VALUE klass)
     return Qtrue;
 }
 
+/* :nodoc: */
 static int
 test_nth_kday(int from, int to, double sg)
 {
@@ -9180,6 +9329,7 @@ test_nth_kday(int from, int to, double sg)
     return 1;
 }
 
+/* :nodoc: */
 static VALUE
 date_s_test_nth_kday(VALUE klass)
 {
@@ -9200,6 +9350,7 @@ date_s_test_nth_kday(VALUE klass)
     return Qtrue;
 }
 
+/* :nodoc: */
 static int
 test_unit_v2v(VALUE i,
 	      VALUE (* conv1)(VALUE),
@@ -9211,6 +9362,7 @@ test_unit_v2v(VALUE i,
     return f_eqeq_p(o, i);
 }
 
+/* :nodoc: */
 static int
 test_unit_v2v_iter2(VALUE (* conv1)(VALUE),
 		    VALUE (* conv2)(VALUE))
@@ -9242,6 +9394,7 @@ test_unit_v2v_iter2(VALUE (* conv1)(VALUE),
     return 1;
 }
 
+/* :nodoc: */
 static int
 test_unit_v2v_iter(VALUE (* conv1)(VALUE),
 		   VALUE (* conv2)(VALUE))
@@ -9253,6 +9406,7 @@ test_unit_v2v_iter(VALUE (* conv1)(VALUE),
     return 1;
 }
 
+/* :nodoc: */
 static VALUE
 date_s_test_unit_conv(VALUE klass)
 {
@@ -9267,6 +9421,7 @@ date_s_test_unit_conv(VALUE klass)
     return Qtrue;
 }
 
+/* :nodoc: */
 static VALUE
 date_s_test_all(VALUE klass)
 {
@@ -9333,6 +9488,7 @@ mk_ary_of_str(long len, const char *a[])
     return o;
 }
 
+/* :nodoc: */
 static VALUE
 d_lite_zero(VALUE x)
 {
@@ -9350,6 +9506,17 @@ Init_date_core(void)
     id_ge_p = rb_intern_const(">=");
     id_eqeq_p = rb_intern_const("==");
 
+    sym_year = ID2SYM(rb_intern_const("year"));
+    sym_month = ID2SYM(rb_intern_const("month"));
+    sym_yday = ID2SYM(rb_intern_const("yday"));
+    sym_wday = ID2SYM(rb_intern_const("wday"));
+    sym_day = ID2SYM(rb_intern_const("day"));
+    sym_hour = ID2SYM(rb_intern_const("hour"));
+    sym_min = ID2SYM(rb_intern_const("min"));
+    sym_sec = ID2SYM(rb_intern_const("sec"));
+    sym_sec_fraction = ID2SYM(rb_intern_const("sec_fraction"));
+    sym_zone = ID2SYM(rb_intern_const("zone"));
+
     half_days_in_day = rb_rational_new2(INT2FIX(1), INT2FIX(2));
 
 #if (LONG_MAX / DAY_IN_SECONDS) > SECOND_IN_NANOSECONDS
@@ -9370,152 +9537,81 @@ Init_date_core(void)
     negative_inf = -INFINITY;
 
     /*
-     * date and datetime class - Tadayoshi Funaba 1998-2011
-     *
-     * 'date' provides two classes: Date and DateTime.
-     *
-     * == Terms and Definitions
-     *
-     * Some terms and definitions are based on ISO 8601 and JIS X 0301.
+     * \Class \Date provides methods for storing and manipulating
+     * calendar dates.
      *
-     * === Calendar Date
+     * Consider using
+     * {class Time}[rdoc-ref:Time]
+     * instead of class \Date if:
      *
-     * The calendar date is a particular day of a calendar year,
-     * identified by its ordinal number within a calendar month within
-     * that year.
+     * - You need both dates and times; \Date handles only dates.
+     * - You need only Gregorian dates (and not Julian dates);
+     *   see {Julian and Gregorian Calendars}[rdoc-ref:calendars.rdoc].
      *
-     * In those classes, this is so-called "civil".
+     * A \Date object, once created, is immutable, and cannot be modified.
      *
-     * === Ordinal Date
+     * == Creating a \Date
      *
-     * The ordinal date is a particular day of a calendar year identified
-     * by its ordinal number within the year.
+     * You can create a date for the current date, using Date.today:
      *
-     * In those classes, this is so-called "ordinal".
+     *   Date.today # => #<Date: 1999-12-31>
      *
-     * === Week Date
+     * You can create a specific date from various combinations of arguments:
      *
-     * The week date is a date identified by calendar week and day numbers.
+     * - Date.new takes integer year, month, and day-of-month:
      *
-     * The calendar week is a seven day period within a calendar year,
-     * starting on a Monday and identified by its ordinal number within
-     * the year; the first calendar week of the year is the one that
-     * includes the first Thursday of that year. In the Gregorian
-     * calendar, this is equivalent to the week which includes January 4.
+     *     Date.new(1999, 12, 31) # => #<Date: 1999-12-31>
      *
-     * In those classes, this is so-called "commercial".
+     * - Date.ordinal takes integer year and day-of-year:
      *
-     * === Julian Day Number
+     *     Date.ordinal(1999, 365) # => #<Date: 1999-12-31>
      *
-     * The Julian day number is in elapsed days since noon (Greenwich Mean
-     * Time) on January 1, 4713 BCE (in the Julian calendar).
+     * - Date.jd takes integer Julian day:
      *
-     * In this document, the astronomical Julian day number is the same as
-     * the original Julian day number. And the chronological Julian day
-     * number is a variation of the Julian day number. Its days begin at
-     * midnight on local time.
+     *     Date.jd(2451544) # => #<Date: 1999-12-31>
      *
-     * In this document, when the term "Julian day number" simply appears,
-     * it just refers to "chronological Julian day number", not the
-     * original.
+     * - Date.commercial takes integer commercial data (year, week, day-of-week):
      *
-     * In those classes, those are so-called "ajd" and "jd".
+     *     Date.commercial(1999, 52, 5) # => #<Date: 1999-12-31>
      *
-     * === Modified Julian Day Number
+     * - Date.parse takes a string, which it parses heuristically:
      *
-     * The modified Julian day number is in elapsed days since midnight
-     * (Coordinated Universal Time) on November 17, 1858 CE (in the
-     * Gregorian calendar).
+     *     Date.parse('1999-12-31')    # => #<Date: 1999-12-31>
+     *     Date.parse('31-12-1999')    # => #<Date: 1999-12-31>
+     *     Date.parse('1999-365')      # => #<Date: 1999-12-31>
+     *     Date.parse('1999-W52-5')    # => #<Date: 1999-12-31>
      *
-     * In this document, the astronomical modified Julian day number is
-     * the same as the original modified Julian day number. And the
-     * chronological modified Julian day number is a variation of the
-     * modified Julian day number. Its days begin at midnight on local
-     * time.
+     * - Date.strptime takes a date string and a format string,
+     *   then parses the date string according to the format string:
      *
-     * In this document, when the term "modified Julian day number" simply
-     * appears, it just refers to "chronological modified Julian day
-     * number", not the original.
+     *     Date.strptime('1999-12-31', '%Y-%m-%d')  # => #<Date: 1999-12-31>
+     *     Date.strptime('31-12-1999', '%d-%m-%Y')  # => #<Date: 1999-12-31>
+     *     Date.strptime('1999-365', '%Y-%j')       # => #<Date: 1999-12-31>
+     *     Date.strptime('1999-W52-5', '%G-W%V-%u') # => #<Date: 1999-12-31>
+     *     Date.strptime('1999 52 5', '%Y %U %w')   # => #<Date: 1999-12-31>
+     *     Date.strptime('1999 52 5', '%Y %W %u')   # => #<Date: 1999-12-31>
+     *     Date.strptime('fri31dec99', '%a%d%b%y')  # => #<Date: 1999-12-31>
      *
-     * In those classes, those are so-called "amjd" and "mjd".
-     *
-     * == Date
-     *
-     * A subclass of Object that includes the Comparable module and
-     * easily handles date.
-     *
-     * A Date object is created with Date::new, Date::jd, Date::ordinal,
-     * Date::commercial, Date::parse, Date::strptime, Date::today,
-     * Time#to_date, etc.
-     *
-     *     require 'date'
+     * See also the specialized methods in
+     * {"Specialized Format Strings" in Formats for Dates and Times}[rdoc-ref:strftime_formatting.rdoc@Specialized+Format+Strings]
      *
-     *     Date.new(2001,2,3)
-     *	    #=> #<Date: 2001-02-03 ...>
-     *     Date.jd(2451944)
-     *	    #=> #<Date: 2001-02-03 ...>
-     *     Date.ordinal(2001,34)
-     *	    #=> #<Date: 2001-02-03 ...>
-     *     Date.commercial(2001,5,6)
-     *	    #=> #<Date: 2001-02-03 ...>
-     *     Date.parse('2001-02-03')
-     *	    #=> #<Date: 2001-02-03 ...>
-     *     Date.strptime('03-02-2001', '%d-%m-%Y')
-     *	    #=> #<Date: 2001-02-03 ...>
-     *     Time.new(2001,2,3).to_date
-     *	    #=> #<Date: 2001-02-03 ...>
+     * == Argument +limit+
      *
-     * All date objects are immutable; hence cannot modify themselves.
+     * Certain singleton methods in \Date that parse string arguments
+     * also take optional keyword argument +limit+,
+     * which can limit the length of the string argument.
      *
-     * The concept of a date object can be represented as a tuple
-     * of the day count, the offset and the day of calendar reform.
+     * When +limit+ is:
      *
-     * The day count denotes the absolute position of a temporal
-     * dimension. The offset is relative adjustment, which determines
-     * decoded local time with the day count. The day of calendar
-     * reform denotes the start day of the new style. The old style
-     * of the West is the Julian calendar which was adopted by
-     * Caesar. The new style is the Gregorian calendar, which is the
-     * current civil calendar of many countries.
-     *
-     * The day count is virtually the astronomical Julian day number.
-     * The offset in this class is usually zero, and cannot be
-     * specified directly.
-     *
-     * A Date object can be created with an optional argument,
-     * the day of calendar reform as a Julian day number, which
-     * should be 2298874 to 2426355 or negative/positive infinity.
-     * The default value is +Date::ITALY+ (2299161=1582-10-15).
-     * See also sample/cal.rb.
-     *
-     *     $ ruby sample/cal.rb -c it 10 1582
-     *         October 1582
-     *      S  M Tu  W Th  F  S
-     *         1  2  3  4 15 16
-     *     17 18 19 20 21 22 23
-     *     24 25 26 27 28 29 30
-     *     31
-     *
-     *     $ ruby sample/cal.rb -c gb  9 1752
-     *        September 1752
-     *      S  M Tu  W Th  F  S
-     *            1  2 14 15 16
-     *     17 18 19 20 21 22 23
-     *     24 25 26 27 28 29 30
-     *
-     * A Date object has various methods. See each reference.
-     *
-     *     d = Date.parse('3rd Feb 2001')
-     *					#=> #<Date: 2001-02-03 ...>
-     *     d.year			#=> 2001
-     *     d.mon			#=> 2
-     *     d.mday			#=> 3
-     *     d.wday			#=> 6
-     *     d += 1			#=> #<Date: 2001-02-04 ...>
-     *     d.strftime('%a %d %b %Y')	#=> "Sun 04 Feb 2001"
+     * - Non-negative:
+     *   raises ArgumentError if the string length is greater than _limit_.
+     * - Other numeric or +nil+: ignores +limit+.
+     * - Other non-numeric: raises TypeError.
      *
      */
     cDate = rb_define_class("Date", rb_cObject);
+
+    /* Exception for invalid date/time */
     eDateError = rb_define_class_under(cDate, "Error", rb_eArgError);
 
     rb_include_module(cDate, rb_mComparable);
@@ -9742,6 +9838,8 @@ Init_date_core(void)
     rb_define_method(cDate, "httpdate", d_lite_httpdate, 0);
     rb_define_method(cDate, "jisx0301", d_lite_jisx0301, 0);
 
+    rb_define_method(cDate, "deconstruct_keys", d_lite_deconstruct_keys, 1);
+
 #ifndef NDEBUG
     rb_define_method(cDate, "marshal_dump_old", d_lite_marshal_dump_old, 0);
 #endif
@@ -9952,6 +10050,8 @@ Init_date_core(void)
     rb_define_method(cDateTime, "rfc3339", dt_lite_rfc3339, -1);
     rb_define_method(cDateTime, "jisx0301", dt_lite_jisx0301, -1);
 
+    rb_define_method(cDateTime, "deconstruct_keys", dt_lite_deconstruct_keys, 1);
+
     /* conversions */
 
     rb_define_method(rb_cTime, "to_time", time_to_time, 0);
diff --git a/ext/date/date_parse.c b/ext/date/date_parse.c
index 95274d5baa..c6f26ecb91 100644
--- a/ext/date/date_parse.c
+++ b/ext/date/date_parse.c
@@ -413,7 +413,6 @@ VALUE
 date_zone_to_diff(VALUE str)
 {
     VALUE offset = Qnil;
-    VALUE vbuf = 0;
     long l = RSTRING_LEN(str);
     const char *s = RSTRING_PTR(str);
 
@@ -439,16 +438,26 @@ date_zone_to_diff(VALUE str)
 	    l -= w;
 	    dst = 1;
 	}
+
 	{
+	    const char *zn = s;
 	    long sl = shrunk_size(s, l);
+	    char shrunk_buff[MAX_WORD_LENGTH]; /* no terminator to be added */
+	    const struct zone *z = 0;
+
+	    if (sl <= 0) {
+		sl = l;
+	    }
+	    else if (sl <= MAX_WORD_LENGTH) {
+		char *d = shrunk_buff;
+		sl = shrink_space(d, s, l);
+		zn = d;
+	    }
+
 	    if (sl > 0 && sl <= MAX_WORD_LENGTH) {
-		char *d = ALLOCV_N(char, vbuf, sl);
-		l = shrink_space(d, s, l);
-		s = d;
+		z = zonetab(zn, (unsigned int)sl);
 	    }
-	}
-	if (l > 0 && l <= MAX_WORD_LENGTH) {
-	    const struct zone *z = zonetab(s, (unsigned int)l);
+
 	    if (z) {
 		int d = z->offset;
 		if (dst)
@@ -457,6 +466,7 @@ date_zone_to_diff(VALUE str)
 		goto ok;
 	    }
 	}
+
 	{
 	    char *p;
 	    int sign = 0;
@@ -473,27 +483,53 @@ date_zone_to_diff(VALUE str)
 		s++;
 		l--;
 
+#define out_of_range(v, min, max) ((v) < (min) || (max) < (v))
 		hour = STRTOUL(s, &p, 10);
 		if (*p == ':') {
+		    if (out_of_range(hour, 0, 23)) return Qnil;
 		    s = ++p;
 		    min = STRTOUL(s, &p, 10);
+		    if (out_of_range(min, 0, 59)) return Qnil;
 		    if (*p == ':') {
 			s = ++p;
 			sec = STRTOUL(s, &p, 10);
+			if (out_of_range(sec, 0, 59)) return Qnil;
 		    }
-		    goto num;
 		}
-		if (*p == ',' || *p == '.') {
-		    char *e = 0;
-		    p++;
-		    min = STRTOUL(p, &e, 10) * 3600;
+		else if (*p == ',' || *p == '.') {
+		    /* fractional hour */
+		    size_t n;
+		    int ov;
+		    /* no over precision for offset; 10**-7 hour = 0.36
+		     * milliseconds should be enough. */
+		    const size_t max_digits = 7; /* 36 * 10**7 < 32-bit FIXNUM_MAX */
+
+		    if (out_of_range(hour, 0, 23)) return Qnil;
+
+		    n = (s + l) - ++p;
+		    if (n > max_digits) n = max_digits;
+		    sec = ruby_scan_digits(p, n, 10, &n, &ov);
+		    if ((p += n) < s + l && *p >= ('5' + !(sec & 1)) && *p <= '9') {
+			/* round half to even */
+			sec++;
+		    }
+		    sec *= 36;
 		    if (sign) {
 			hour = -hour;
-			min = -min;
+			sec = -sec;
+		    }
+		    if (n <= 2) {
+			/* HH.nn or HH.n */
+			if (n == 1) sec *= 10;
+			offset = INT2FIX(sec + hour * 3600);
+		    }
+		    else {
+			VALUE denom = rb_int_positive_pow(10, (int)(n - 2));
+			offset = f_add(rb_rational_new(INT2FIX(sec), denom), INT2FIX(hour * 3600));
+			if (rb_rational_den(offset) == INT2FIX(1)) {
+			    offset = rb_rational_num(offset);
+			}
 		    }
-		    offset = rb_rational_new(INT2FIX(min),
-					     rb_int_positive_pow(10, (int)(e - p)));
-		    offset = f_add(INT2FIX(hour * 3600), offset);
 		    goto ok;
 		}
 		else if (l > 2) {
@@ -506,18 +542,16 @@ date_zone_to_diff(VALUE str)
 			min  = ruby_scan_digits(&s[2 - l % 2], 2, 10, &n, &ov);
 		    if (l >= 5)
 			sec  = ruby_scan_digits(&s[4 - l % 2], 2, 10, &n, &ov);
-		    goto num;
 		}
-	      num:
 		sec += min * 60 + hour * 3600;
 		if (sign) sec = -sec;
 		offset = INT2FIX(sec);
+#undef out_of_range
 	    }
 	}
     }
     RB_GC_GUARD(str);
   ok:
-    ALLOCV_END(vbuf);
     return offset;
 }
 
diff --git a/ext/date/date_strptime.c b/ext/date/date_strptime.c
index 7b06a31471..f731629df1 100644
--- a/ext/date/date_strptime.c
+++ b/ext/date/date_strptime.c
@@ -10,28 +10,15 @@
 static const char *day_names[] = {
     "Sunday", "Monday", "Tuesday", "Wednesday",
     "Thursday", "Friday", "Saturday",
-    "Sun", "Mon", "Tue", "Wed",
-    "Thu", "Fri", "Sat"
 };
+static const int ABBREVIATED_DAY_NAME_LENGTH = 3;
 
 static const char *month_names[] = {
     "January", "February", "March", "April",
     "May", "June", "July", "August", "September",
     "October", "November", "December",
-    "Jan", "Feb", "Mar", "Apr", "May", "Jun",
-    "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
-};
-
-static const char *merid_names[] = {
-    "am", "pm",
-    "a.m.", "p.m."
-};
-
-static const char *extz_pats[] = {
-    ":z",
-    "::z",
-    ":::z"
 };
+static const int ABBREVIATED_MONTH_NAME_LENGTH = 3;
 
 #define sizeof_array(o) (sizeof o / sizeof o[0])
 
@@ -75,7 +62,7 @@ num_pattern_p(const char *s)
 #define NUM_PATTERN_P() num_pattern_p(&fmt[fi + 1])
 
 static long
-read_digits(const char *s, VALUE *n, size_t width)
+read_digits(const char *s, size_t slen, VALUE *n, size_t width)
 {
     size_t l;
 
@@ -83,7 +70,7 @@ read_digits(const char *s, VALUE *n, size_t width)
         return 0;
 
     l = 0;
-    while (ISDIGIT(s[l])) {
+    while (l < slen && ISDIGIT(s[l])) {
         if (++l == width) break;
     }
 
@@ -131,7 +118,7 @@ do { \
 #define READ_DIGITS(n,w) \
 do { \
     size_t l; \
-    l = read_digits(&str[si], &n, w); \
+    l = read_digits(&str[si], slen - si, &n, w); \
     if (l == 0) \
 	fail();	\
     si += l; \
@@ -161,6 +148,12 @@ do { \
 
 VALUE date_zone_to_diff(VALUE);
 
+static inline int
+head_match_p(size_t len, const char *name, const char *str, size_t slen, size_t si)
+{
+    return slen - si >= len && strncasecmp(name, &str[si], len) == 0;
+}
+
 static size_t
 date__strptime_internal(const char *str, size_t slen,
 			const char *fmt, size_t flen, VALUE hash)
@@ -168,9 +161,18 @@ date__strptime_internal(const char *str, size_t slen,
     size_t si, fi;
     int c;
 
+#define HEAD_MATCH_P(len, name) head_match_p(len, name, str, slen, si)
     si = fi = 0;
 
     while (fi < flen) {
+	if (isspace((unsigned char)fmt[fi])) {
+	    while (si < slen && isspace((unsigned char)str[si]))
+		si++;
+	    while (++fi < flen && isspace((unsigned char)fmt[fi]));
+	    continue;
+	}
+
+	if (si >= slen) fail();
 
 	switch (fmt[fi]) {
 	  case '%':
@@ -194,12 +196,11 @@ date__strptime_internal(const char *str, size_t slen,
 		{
 		    int i;
 
-		    for (i = 0; i < (int)sizeof_array(extz_pats); i++)
-			if (strncmp(extz_pats[i], &fmt[fi],
-					strlen(extz_pats[i])) == 0) {
-			    fi += i;
-			    goto again;
-			}
+		    for (i = 1; i < 3 && fi + i < flen && fmt[fi+i] == ':'; ++i);
+		    if (fmt[fi+i] == 'z') {
+			fi += i - 1;
+			goto again;
+		    }
 		    fail();
 		}
 
@@ -209,10 +210,12 @@ date__strptime_internal(const char *str, size_t slen,
 		    int i;
 
 		    for (i = 0; i < (int)sizeof_array(day_names); i++) {
-			size_t l = strlen(day_names[i]);
-			if (strncasecmp(day_names[i], &str[si], l) == 0) {
+			const char *day_name = day_names[i];
+			size_t l = strlen(day_name);
+			if (HEAD_MATCH_P(l, day_name) ||
+			    HEAD_MATCH_P(l = ABBREVIATED_DAY_NAME_LENGTH, day_name)) {
 			    si += l;
-			    set_hash("wday", INT2FIX(i % 7));
+			    set_hash("wday", INT2FIX(i));
 			    goto matched;
 			}
 		    }
@@ -225,10 +228,12 @@ date__strptime_internal(const char *str, size_t slen,
 		    int i;
 
 		    for (i = 0; i < (int)sizeof_array(month_names); i++) {
-			size_t l = strlen(month_names[i]);
-			if (strncasecmp(month_names[i], &str[si], l) == 0) {
+			const char *month_name = month_names[i];
+			size_t l = strlen(month_name);
+			if (HEAD_MATCH_P(l, month_name) ||
+			    HEAD_MATCH_P(l = ABBREVIATED_MONTH_NAME_LENGTH, month_name)) {
 			    si += l;
-			    set_hash("mon", INT2FIX((i % 12) + 1));
+			    set_hash("mon", INT2FIX(i + 1));
 			    goto matched;
 			}
 		    }
@@ -402,18 +407,19 @@ date__strptime_internal(const char *str, size_t slen,
 
 	      case 'P':
 	      case 'p':
+		if (slen - si < 2) fail();
 		{
-		    int i;
-
-		    for (i = 0; i < 4; i++) {
-			size_t l = strlen(merid_names[i]);
-			if (strncasecmp(merid_names[i], &str[si], l) == 0) {
-			    si += l;
-			    set_hash("_merid", INT2FIX((i % 2) == 0 ? 0 : 12));
-			    goto matched;
-			}
+		    char c = str[si];
+		    const int hour = (c == 'P' || c == 'p') ? 12 : 0;
+		    if (!hour && !(c == 'A' || c == 'a')) fail();
+		    if ((c = str[si+1]) == '.') {
+			if (slen - si < 4 || str[si+3] != '.') fail();
+			c = str[si += 2];
 		    }
-		    fail();
+		    if (!(c == 'M' || c == 'm')) fail();
+		    si += 2;
+		    set_hash("_merid", INT2FIX(hour));
+		    goto matched;
 		}
 
 	      case 'Q':
@@ -587,7 +593,7 @@ date__strptime_internal(const char *str, size_t slen,
 
 		    b = rb_backref_get();
 		    rb_match_busy(b);
-		    m = f_match(pat, rb_usascii_str_new2(&str[si]));
+		    m = f_match(pat, rb_usascii_str_new(&str[si], slen - si));
 
 		    if (!NIL_P(m)) {
 			VALUE s, l, o;
@@ -619,22 +625,13 @@ date__strptime_internal(const char *str, size_t slen,
 		if (str[si] != '%')
 		    fail();
 		si++;
-		if (fi < flen)
-		    if (str[si] != fmt[fi])
+		if (fi < flen) {
+		    if (si >= slen || str[si] != fmt[fi])
 			fail();
-		si++;
+		    si++;
+		}
 		goto matched;
 	    }
-	  case ' ':
-	  case '\t':
-	  case '\n':
-	  case '\v':
-	  case '\f':
-	  case '\r':
-	    while (isspace((unsigned char)str[si]))
-		si++;
-	    fi++;
-	    break;
 	  default:
 	  ordinal:
 	    if (str[si] != fmt[fi])
diff --git a/ext/date/lib/date.rb b/ext/date/lib/date.rb
index 5770187a8e..a9fe3ce4b0 100644
--- a/ext/date/lib/date.rb
+++ b/ext/date/lib/date.rb
@@ -4,8 +4,12 @@
 require 'date_core'
 
 class Date
-  VERSION = '3.2.2' # :nodoc:
+  VERSION = "3.3.3" # :nodoc:
 
+  # call-seq:
+  #   infinite? -> false
+  #
+  # Returns +false+
   def infinite?
     false
   end
diff --git a/ext/date/zonetab.h b/ext/date/zonetab.h
index d82b011dc1..7ced9e0308 100644
--- a/ext/date/zonetab.h
+++ b/ext/date/zonetab.h
@@ -36,7 +36,7 @@ struct zone {
     int name;
     int offset;
 };
-static const struct zone *zonetab();
+static const struct zone *zonetab(register const char *str, register size_t len);
 #line 9 "zonetab.list"
 struct zone;
 
@@ -49,7 +49,7 @@ struct zone;
 
 #ifndef GPERF_DOWNCASE
 #define GPERF_DOWNCASE 1
-static unsigned char gperf_downcase[256] =
+static const unsigned char gperf_downcase[256] =
   {
       0,   1,   2,   3,   4,   5,   6,   7,   8,   9,  10,  11,  12,  13,  14,
      15,  16,  17,  18,  19,  20,  21,  22,  23,  24,  25,  26,  27,  28,  29,
diff --git a/ext/date/zonetab.list b/ext/date/zonetab.list
index d2f902d2d5..748aec1d8a 100644
--- a/ext/date/zonetab.list
+++ b/ext/date/zonetab.list
@@ -3,7 +3,7 @@ struct zone {
     int name;
     int offset;
 };
-static const struct zone *zonetab();
+static const struct zone *zonetab(register const char *str, register size_t len);
 %}
 
 struct zone;
diff --git a/ext/digest/bubblebabble/bubblebabble.c b/ext/digest/bubblebabble/bubblebabble.c
index 6557e43c9d..358ab416b9 100644
--- a/ext/digest/bubblebabble/bubblebabble.c
+++ b/ext/digest/bubblebabble/bubblebabble.c
@@ -37,7 +37,7 @@ bubblebabble_str_new(VALUE str_digest)
     digest_len = RSTRING_LEN(str_digest);
 
     if ((LONG_MAX - 2) / 3 < (digest_len | 1)) {
-	rb_raise(rb_eRuntimeError, "digest string too long");
+        rb_raise(rb_eRuntimeError, "digest string too long");
     }
 
     str = rb_str_new(0, (digest_len | 1) * 3 + 2);
diff --git a/ext/digest/digest.c b/ext/digest/digest.c
index 83f4ee42fc..68837a674c 100644
--- a/ext/digest/digest.c
+++ b/ext/digest/digest.c
@@ -154,7 +154,7 @@ static void
 rb_digest_instance_method_unimpl(VALUE self, const char *method)
 {
     rb_raise(rb_eRuntimeError, "%s does not implement %s()",
-	     rb_obj_classname(self), method);
+             rb_obj_classname(self), method);
 }
 
 /*
@@ -383,8 +383,8 @@ rb_digest_instance_equal(VALUE self, VALUE other)
     StringValue(str2);
 
     if (RSTRING_LEN(str1) == RSTRING_LEN(str2) &&
-	rb_str_cmp(str1, str2) == 0) {
-	return Qtrue;
+        rb_str_cmp(str1, str2) == 0) {
+        return Qtrue;
     }
     return Qfalse;
 }
@@ -602,7 +602,7 @@ static inline void
 algo_init(const rb_digest_metadata_t *algo, void *pctx)
 {
     if (algo->init_func(pctx) != 1) {
-	rb_raise(rb_eRuntimeError, "Digest initialization failed.");
+        rb_raise(rb_eRuntimeError, "Digest initialization failed.");
     }
 }
 
@@ -614,7 +614,7 @@ rb_digest_base_alloc(VALUE klass)
     void *pctx;
 
     if (klass == rb_cDigest_Base) {
-	rb_raise(rb_eNotImpError, "Digest::Base is an abstract class");
+        rb_raise(rb_eNotImpError, "Digest::Base is an abstract class");
     }
 
     algo = get_digest_base_metadata(klass);
@@ -639,7 +639,7 @@ rb_digest_base_copy(VALUE copy, VALUE obj)
 
     algo = get_digest_obj_metadata(copy);
     if (algo != get_digest_obj_metadata(obj))
-	rb_raise(rb_eTypeError, "different algorithms");
+        rb_raise(rb_eTypeError, "different algorithms");
 
     TypedData_Get_Struct(obj, void, &digest_type, pctx1);
     TypedData_Get_Struct(copy, void, &digest_type, pctx2);
diff --git a/ext/digest/digest.h b/ext/digest/digest.h
index 0d4f0e7cc2..8a4c5b7e4e 100644
--- a/ext/digest/digest.h
+++ b/ext/digest/digest.h
@@ -38,7 +38,7 @@ rb_digest_##name##_update(void *ctx, unsigned char *ptr, size_t size) \
     const unsigned int stride = 16384; \
  \
     for (; size > stride; size -= stride, ptr += stride) { \
-	name##_Update(ctx, ptr, stride); \
+        name##_Update(ctx, ptr, stride); \
     } \
     if (size > 0) name##_Update(ctx, ptr, size); \
 }
diff --git a/ext/digest/digest_conf.rb b/ext/digest/digest_conf.rb
index 1b929d8732..36a7d75289 100644
--- a/ext/digest/digest_conf.rb
+++ b/ext/digest/digest_conf.rb
@@ -3,7 +3,7 @@
 def digest_conf(name)
   unless with_config("bundled-#{name}")
     cc = with_config("common-digest")
-    if cc == true or /\b#{name}\b/ =~ cc
+    if cc != false or /\b#{name}\b/ =~ cc
       if File.exist?("#$srcdir/#{name}cc.h") and
         have_header("CommonCrypto/CommonDigest.h")
         $defs << "-D#{name.upcase}_USE_COMMONDIGEST"
diff --git a/ext/digest/lib/digest/version.rb b/ext/digest/lib/digest/version.rb
index 79e6aeee99..42fd7acf6e 100644
--- a/ext/digest/lib/digest/version.rb
+++ b/ext/digest/lib/digest/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module Digest
-  VERSION = "3.1.0"
+  VERSION = "3.1.1"
 end
diff --git a/ext/digest/md5/depend b/ext/digest/md5/depend
index 0353e7a40d..ea1ceec7fd 100644
--- a/ext/digest/md5/depend
+++ b/ext/digest/md5/depend
@@ -326,5 +326,6 @@ md5init.o: $(hdrdir)/ruby/subst.h
 md5init.o: $(srcdir)/../defs.h
 md5init.o: $(srcdir)/../digest.h
 md5init.o: md5.h
+md5init.o: md5cc.h
 md5init.o: md5init.c
 # AUTOGENERATED DEPENDENCIES END
diff --git a/ext/digest/sha1/depend b/ext/digest/sha1/depend
index a4e454d214..48aaef158b 100644
--- a/ext/digest/sha1/depend
+++ b/ext/digest/sha1/depend
@@ -326,5 +326,6 @@ sha1init.o: $(hdrdir)/ruby/subst.h
 sha1init.o: $(srcdir)/../defs.h
 sha1init.o: $(srcdir)/../digest.h
 sha1init.o: sha1.h
+sha1init.o: sha1cc.h
 sha1init.o: sha1init.c
 # AUTOGENERATED DEPENDENCIES END
diff --git a/ext/digest/sha2/depend b/ext/digest/sha2/depend
index 2fb598aa48..47a859068c 100644
--- a/ext/digest/sha2/depend
+++ b/ext/digest/sha2/depend
@@ -325,5 +325,6 @@ sha2init.o: $(hdrdir)/ruby/st.h
 sha2init.o: $(hdrdir)/ruby/subst.h
 sha2init.o: $(srcdir)/../digest.h
 sha2init.o: sha2.h
+sha2init.o: sha2cc.h
 sha2init.o: sha2init.c
 # AUTOGENERATED DEPENDENCIES END
diff --git a/ext/digest/sha2/sha2init.c b/ext/digest/sha2/sha2init.c
index 6ed275eb71..94cccf3feb 100644
--- a/ext/digest/sha2/sha2init.c
+++ b/ext/digest/sha2/sha2init.c
@@ -47,7 +47,7 @@ Init_sha2(void)
     cDigest_SHA##bitlen = rb_define_class_under(mDigest, "SHA" #bitlen, cDigest_Base); \
 \
     rb_ivar_set(cDigest_SHA##bitlen, id_metadata, \
-		rb_digest_make_metadata(&sha##bitlen));
+                rb_digest_make_metadata(&sha##bitlen));
 
     FOREACH_BITLEN(DEFINE_ALGO_CLASS)
 }
diff --git a/ext/erb/escape/escape.c b/ext/erb/escape/escape.c
new file mode 100644
index 0000000000..67b2d1ef34
--- /dev/null
+++ b/ext/erb/escape/escape.c
@@ -0,0 +1,95 @@
+#include "ruby.h"
+#include "ruby/encoding.h"
+
+static VALUE rb_cERB, rb_mEscape, rb_cCGI;
+static ID id_escapeHTML;
+
+#define HTML_ESCAPE_MAX_LEN 6
+
+static const struct {
+    uint8_t len;
+    char str[HTML_ESCAPE_MAX_LEN+1];
+} html_escape_table[UCHAR_MAX+1] = {
+#define HTML_ESCAPE(c, str) [c] = {rb_strlen_lit(str), str}
+    HTML_ESCAPE('\'', "&#39;"),
+    HTML_ESCAPE('&', "&amp;"),
+    HTML_ESCAPE('"', "&quot;"),
+    HTML_ESCAPE('<', "&lt;"),
+    HTML_ESCAPE('>', "&gt;"),
+#undef HTML_ESCAPE
+};
+
+static inline void
+preserve_original_state(VALUE orig, VALUE dest)
+{
+    rb_enc_associate(dest, rb_enc_get(orig));
+}
+
+static inline long
+escaped_length(VALUE str)
+{
+    const long len = RSTRING_LEN(str);
+    if (len >= LONG_MAX / HTML_ESCAPE_MAX_LEN) {
+        ruby_malloc_size_overflow(len, HTML_ESCAPE_MAX_LEN);
+    }
+    return len * HTML_ESCAPE_MAX_LEN;
+}
+
+static VALUE
+optimized_escape_html(VALUE str)
+{
+    VALUE vbuf;
+    char *buf = ALLOCV_N(char, vbuf, escaped_length(str));
+    const char *cstr = RSTRING_PTR(str);
+    const char *end = cstr + RSTRING_LEN(str);
+
+    char *dest = buf;
+    while (cstr < end) {
+        const unsigned char c = *cstr++;
+        uint8_t len = html_escape_table[c].len;
+        if (len) {
+            memcpy(dest, html_escape_table[c].str, len);
+            dest += len;
+        }
+        else {
+            *dest++ = c;
+        }
+    }
+
+    VALUE escaped = str;
+    if (RSTRING_LEN(str) < (dest - buf)) {
+        escaped = rb_str_new(buf, dest - buf);
+        preserve_original_state(str, escaped);
+    }
+    ALLOCV_END(vbuf);
+    return escaped;
+}
+
+// ERB::Util.html_escape is different from CGI.escapeHTML in the following two parts:
+//   * ERB::Util.html_escape converts an argument with #to_s first (only if it's not T_STRING)
+//   * ERB::Util.html_escape does not allocate a new string when nothing needs to be escaped
+static VALUE
+erb_escape_html(VALUE self, VALUE str)
+{
+    if (!RB_TYPE_P(str, T_STRING)) {
+        str = rb_convert_type(str, T_STRING, "String", "to_s");
+    }
+
+    if (rb_enc_str_asciicompat_p(str)) {
+        return optimized_escape_html(str);
+    }
+    else {
+        return rb_funcall(rb_cCGI, id_escapeHTML, 1, str);
+    }
+}
+
+void
+Init_escape(void)
+{
+    rb_cERB = rb_define_class("ERB", rb_cObject);
+    rb_mEscape = rb_define_module_under(rb_cERB, "Escape");
+    rb_define_module_function(rb_mEscape, "html_escape", erb_escape_html, 1);
+
+    rb_cCGI = rb_define_class("CGI", rb_cObject);
+    id_escapeHTML = rb_intern("escapeHTML");
+}
diff --git a/ext/erb/escape/extconf.rb b/ext/erb/escape/extconf.rb
new file mode 100644
index 0000000000..c1002548ad
--- /dev/null
+++ b/ext/erb/escape/extconf.rb
@@ -0,0 +1,7 @@
+require 'mkmf'
+
+if RUBY_ENGINE == 'truffleruby'
+  File.write('Makefile', dummy_makefile($srcdir).join)
+else
+  create_makefile 'erb/escape'
+end
diff --git a/ext/etc/etc.c b/ext/etc/etc.c
index 9a691d6e34..6c7145b40b 100644
--- a/ext/etc/etc.c
+++ b/ext/etc/etc.c
@@ -47,12 +47,16 @@ static VALUE sGroup;
 #define HAVE_UNAME 1
 #endif
 
-#ifndef _WIN32
-char *getenv();
+#ifdef STDC_HEADERS
+# include <stdlib.h>
+#else
+# ifdef HAVE_STDLIB_H
+#  include <stdlib.h>
+# endif
 #endif
 char *getlogin();
 
-#define RUBY_ETC_VERSION "1.4.0"
+#define RUBY_ETC_VERSION "1.4.2"
 
 #ifdef HAVE_RB_DEPRECATE_CONSTANT
 void rb_deprecate_constant(VALUE mod, const char *name);
@@ -190,7 +194,8 @@ setup_passwd(struct passwd *pwd)
 /* call-seq:
  *	getpwuid(uid)	->  Passwd
  *
- * Returns the /etc/passwd information for the user with the given integer +uid+.
+ * Returns the <tt>/etc/passwd</tt> information for the user with the given
+ * integer +uid+.
  *
  * The information is returned as a Passwd struct.
  *
@@ -229,8 +234,8 @@ etc_getpwuid(int argc, VALUE *argv, VALUE obj)
 /* call-seq:
  *	getpwnam(name)	->  Passwd
  *
- * Returns the /etc/passwd information for the user with specified login
- * +name+.
+ * Returns the <tt>/etc/passwd</tt> information for the user with specified
+ * login +name+.
  *
  * The information is returned as a Passwd struct.
  *
@@ -295,7 +300,7 @@ each_passwd(void)
  *	Etc.passwd			->  Passwd
  *
  * Provides a convenient Ruby iterator which executes a block for each entry
- * in the /etc/passwd file.
+ * in the <tt>/etc/passwd</tt> file.
  *
  * The code block is passed an Passwd struct.
  *
@@ -330,13 +335,14 @@ etc_passwd(VALUE obj)
  *	Etc::Passwd.each { |struct| block }	->  Passwd
  *	Etc::Passwd.each			->  Enumerator
  *
- * Iterates for each entry in the /etc/passwd file if a block is given.
+ * Iterates for each entry in the <tt>/etc/passwd</tt> file if a block is
+ * given.
  *
  * If no block is given, returns the Enumerator.
  *
  * The code block is passed an Passwd struct.
  *
- * See ::getpwent above for details.
+ * See Etc.getpwent above for details.
  *
  * Example:
  *
@@ -360,8 +366,8 @@ etc_each_passwd(VALUE obj)
     return obj;
 }
 
-/* Resets the process of reading the /etc/passwd file, so that the next call
- * to ::getpwent will return the first entry again.
+/* Resets the process of reading the <tt>/etc/passwd</tt> file, so that the
+ * next call to ::getpwent will return the first entry again.
  */
 static VALUE
 etc_setpwent(VALUE obj)
@@ -372,8 +378,8 @@ etc_setpwent(VALUE obj)
     return Qnil;
 }
 
-/* Ends the process of scanning through the /etc/passwd file begun with
- * ::getpwent, and closes the file.
+/* Ends the process of scanning through the <tt>/etc/passwd</tt> file begun
+ * with ::getpwent, and closes the file.
  */
 static VALUE
 etc_endpwent(VALUE obj)
@@ -384,7 +390,7 @@ etc_endpwent(VALUE obj)
     return Qnil;
 }
 
-/* Returns an entry from the /etc/passwd file.
+/* Returns an entry from the <tt>/etc/passwd</tt> file.
  *
  * The first time it is called it opens the file and returns the first entry;
  * each successive call returns the next entry, or +nil+ if the end of the file
@@ -435,7 +441,7 @@ setup_group(struct group *grp)
  *	getgrgid(group_id)  ->	Group
  *
  * Returns information about the group with specified integer +group_id+,
- * as found in /etc/group.
+ * as found in <tt>/etc/group</tt>.
  *
  * The information is returned as a Group struct.
  *
@@ -473,7 +479,7 @@ etc_getgrgid(int argc, VALUE *argv, VALUE obj)
  *	getgrnam(name)	->  Group
  *
  * Returns information about the group with specified +name+, as found in
- * /etc/group.
+ * <tt>/etc/group</tt>.
  *
  * The information is returned as a Group struct.
  *
@@ -536,7 +542,7 @@ each_group(void)
 #endif
 
 /* Provides a convenient Ruby iterator which executes a block for each entry
- * in the /etc/group file.
+ * in the <tt>/etc/group</tt> file.
  *
  * The code block is passed an Group struct.
  *
@@ -572,7 +578,8 @@ etc_group(VALUE obj)
  *	Etc::Group.each { |group| block }   ->	obj
  *	Etc::Group.each			    ->	Enumerator
  *
- * Iterates for each entry in the /etc/group file if a block is given.
+ * Iterates for each entry in the <tt>/etc/group</tt> file if a block is
+ * given.
  *
  * If no block is given, returns the Enumerator.
  *
@@ -599,8 +606,8 @@ etc_each_group(VALUE obj)
 }
 #endif
 
-/* Resets the process of reading the /etc/group file, so that the next call
- * to ::getgrent will return the first entry again.
+/* Resets the process of reading the <tt>/etc/group</tt> file, so that the
+ * next call to ::getgrent will return the first entry again.
  */
 static VALUE
 etc_setgrent(VALUE obj)
@@ -611,8 +618,8 @@ etc_setgrent(VALUE obj)
     return Qnil;
 }
 
-/* Ends the process of scanning through the /etc/group file begun by
- * ::getgrent, and closes the file.
+/* Ends the process of scanning through the <tt>/etc/group</tt> file begun
+ * by ::getgrent, and closes the file.
  */
 static VALUE
 etc_endgrent(VALUE obj)
@@ -623,7 +630,7 @@ etc_endgrent(VALUE obj)
     return Qnil;
 }
 
-/* Returns an entry from the /etc/group file.
+/* Returns an entry from the <tt>/etc/group</tt> file.
  *
  * The first time it is called it opens the file and returns the first entry;
  * each successive call returns the next entry, or +nil+ if the end of the file
@@ -657,9 +664,11 @@ VALUE rb_w32_conv_from_wchar(const WCHAR *wstr, rb_encoding *enc);
 /*
  * Returns system configuration directory.
  *
- * This is typically "/etc", but is modified by the prefix used when Ruby was
- * compiled. For example, if Ruby is built and installed in /usr/local,
- * returns "/usr/local/etc" on other platforms than Windows.
+ * This is typically <code>"/etc"</code>, but is modified by the prefix used
+ * when Ruby was compiled. For example, if Ruby is built and installed in
+ * <tt>/usr/local</tt>, returns <code>"/usr/local/etc"</code> on other
+ * platforms than Windows.
+ *
  * On Windows, this always returns the directory provided by the system.
  */
 static VALUE
@@ -1067,11 +1076,12 @@ etc_nprocessors(VALUE obj)
 
 /*
  * The Etc module provides access to information typically stored in
- * files in the /etc directory on Unix systems.
+ * files in the <tt>/etc</tt> directory on Unix systems.
  *
  * The information accessible consists of the information found in the
- * /etc/passwd and /etc/group files, plus information about the system's
- * temporary directory (/tmp) and configuration directory (/etc).
+ * <tt>/etc/passwd</tt> and <tt>/etc/group</tt> files, plus information
+ * about the system's temporary directory (<tt>/tmp</tt>) and configuration
+ * directory (<tt>/etc</tt>).
  *
  * The Etc module provides a more reliable way to access information about
  * the logged in user than environment variables such as +$USER+.
@@ -1096,9 +1106,9 @@ Init_etc(void)
 {
     VALUE mEtc;
 
-    #ifdef HAVE_RB_EXT_RACTOR_SAFE
-	RB_EXT_RACTOR_SAFE(true);
-    #endif
+#ifdef HAVE_RB_EXT_RACTOR_SAFE
+    RB_EXT_RACTOR_SAFE(true);
+#endif
     mEtc = rb_define_module("Etc");
     rb_define_const(mEtc, "VERSION", rb_str_new_cstr(RUBY_ETC_VERSION));
     init_constants(mEtc);
@@ -1159,14 +1169,17 @@ Init_etc(void)
 				      NULL);
 #if 0
     /*
-     * Passwd is a Struct that contains the following members:
+     * Passwd is a placeholder Struct for user database on Unix systems.
+     *
+     * === The struct contains the following members
      *
      * name::
      *	    contains the short login name of the user as a String.
      * passwd::
      *	    contains the encrypted password of the user as a String.
-     *	    an 'x' is returned if shadow passwords are in use. An '*' is returned
-     *      if the user cannot log in using a password.
+     *	    an <code>'x'</code> is returned if shadow passwords are in
+     *	    use. An <code>'*'</code> is returned if the user cannot
+     *	    log in using a password.
      * uid::
      *	    contains the integer user ID (uid) of the user.
      * gid::
@@ -1176,25 +1189,24 @@ Init_etc(void)
      * shell::
      *	    contains the path to the login shell of the user as a String.
      *
-     * === The following members below are optional, and must be compiled with special flags:
+     * === The following members below are system-dependent
      *
      * gecos::
      *     contains a longer String description of the user, such as
      *	   a full name. Some Unix systems provide structured information in the
      *     gecos field, but this is system-dependent.
-     *     must be compiled with +HAVE_STRUCT_PASSWD_PW_GECOS+
      * change::
-     *     password change time(integer) must be compiled with +HAVE_STRUCT_PASSWD_PW_CHANGE+
+     *     password change time(integer).
      * quota::
-     *     quota value(integer) must be compiled with +HAVE_STRUCT_PASSWD_PW_QUOTA+
+     *     quota value(integer).
      * age::
-     *     password age(integer) must be compiled with +HAVE_STRUCT_PASSWD_PW_AGE+
+     *     password age(integer).
      * class::
-     *     user access class(string) must be compiled with +HAVE_STRUCT_PASSWD_PW_CLASS+
+     *     user access class(string).
      * comment::
-     *     comment(string) must be compiled with +HAVE_STRUCT_PASSWD_PW_COMMENT+
+     *     comment(string).
      * expire::
-     *	    account expiration time(integer) must be compiled with +HAVE_STRUCT_PASSWD_PW_EXPIRE+
+     *	    account expiration time(integer).
      */
     sPasswd = rb_define_class_under(mEtc, "Passwd", rb_cStruct);
 #endif
@@ -1210,9 +1222,9 @@ Init_etc(void)
 
 #if 0
     /*
-     * Group is a Struct that is only available when compiled with +HAVE_GETGRENT+.
+     * Group is a placeholder Struct for user group database on Unix systems.
      *
-     * The struct contains the following members:
+     * === The struct contains the following members
      *
      * name::
      *	    contains the name of the group as a String.
@@ -1221,7 +1233,7 @@ Init_etc(void)
      *	    returned if password access to the group is not available; an empty
      *	    string is returned if no password is needed to obtain membership of
      *	    the group.
-     *	    Must be compiled with +HAVE_STRUCT_GROUP_GR_PASSWD+.
+     *	    This is system-dependent.
      * gid::
      *	    contains the group's numeric ID as an integer.
      * mem::
diff --git a/ext/extmk.rb b/ext/extmk.rb
index a440af27fc..4e77a7167b 100755
--- a/ext/extmk.rb
+++ b/ext/extmk.rb
@@ -37,6 +37,7 @@ require 'rbconfig'
 
 $topdir = "."
 $top_srcdir = srcdir
+inplace = File.identical?($top_srcdir, $topdir)
 
 $" << "mkmf.rb"
 load File.expand_path("lib/mkmf.rb", srcdir)
@@ -65,12 +66,17 @@ end
 
 def atomic_write_open(filename)
   filename_new = filename + ".new.#$$"
-  open(filename_new, "wb") do |f|
+  clean = false
+  File.open(filename_new, "wbx") do |f|
+    clean = true
     yield f
   end
   if File.binread(filename_new) != (File.binread(filename) rescue nil)
     File.rename(filename_new, filename)
-  else
+    clean = false
+  end
+ensure
+  if clean
     File.unlink(filename_new)
   end
 end
@@ -130,6 +136,14 @@ def extract_makefile(makefile, keep = true)
   true
 end
 
+def create_makefile(target, srcprefix = nil)
+  if $static and target.include?("/")
+    base = File.basename(target)
+    $defs << "-DInit_#{base}=Init_#{target.tr('/', '_')}"
+  end
+  super
+end
+
 def extmake(target, basedir = 'ext', maybestatic = true)
   FileUtils.mkpath target unless File.directory?(target)
   begin
@@ -138,7 +152,7 @@ def extmake(target, basedir = 'ext', maybestatic = true)
     d = target
     until (d = File.dirname(d)) == '.'
       if File.exist?("#{$top_srcdir}/#{basedir}/#{d}/extconf.rb")
-        parent = (/^all:\s*install/ =~ IO.read("#{d}/Makefile") rescue false)
+        parent = (/^all:\s*install/ =~ File.read("#{d}/Makefile") rescue false)
         break
       end
     end
@@ -157,8 +171,6 @@ def extmake(target, basedir = 'ext', maybestatic = true)
     $mdir = target
     $srcdir = File.join($top_srcdir, basedir, $mdir)
     $preload = nil
-    $objs = []
-    $srcs = []
     $extso = []
     makefile = "./Makefile"
     static = $static
@@ -192,7 +204,7 @@ def extmake(target, basedir = 'ext', maybestatic = true)
       begin
 	$extconf_h = nil
 	ok &&= extract_makefile(makefile)
-	old_objs = $objs
+	old_objs = $objs || []
 	old_cleanfiles = $distcleanfiles | $cleanfiles
 	conf = ["#{$srcdir}/makefile.rb", "#{$srcdir}/extconf.rb"].find {|f| File.exist?(f)}
 	if (!ok || ($extconf_h && !File.exist?($extconf_h)) ||
@@ -255,6 +267,8 @@ def extmake(target, basedir = 'ext', maybestatic = true)
     unless $destdir.to_s.empty? or $mflags.defined?("DESTDIR")
       args += ["DESTDIR=" + relative_from($destdir, "../"+prefix)]
     end
+    $objs ||= []
+    $srcs ||= []
     if $static and ok and !$objs.empty? and !noinstall
       args += ["static"]
       $extlist.push [(maybestatic ? $static : false), target, $target, $preload]
@@ -411,8 +425,10 @@ if CROSS_COMPILING
   $ruby = $mflags.defined?("MINIRUBY") || CONFIG['MINIRUBY']
 elsif sep = config_string('BUILD_FILE_SEPARATOR')
   $ruby = "$(topdir:/=#{sep})#{sep}miniruby" + EXEEXT
-else
+elsif CONFIG['EXTSTATIC']
   $ruby = '$(topdir)/miniruby' + EXEEXT
+else
+  $ruby = '$(topdir)/ruby' + EXEEXT
 end
 $ruby = [$ruby]
 $ruby << "-I'$(topdir)'"
@@ -424,6 +440,7 @@ end
 topruby = $ruby
 $ruby = topruby.join(' ')
 $mflags << "ruby=#$ruby"
+$builtruby = '$(topdir)/miniruby' + EXEEXT # Must be an executable path
 
 MTIMES = [__FILE__, 'rbconfig.rb', srcdir+'/lib/mkmf.rb'].collect {|f| File.mtime(f)}
 
@@ -438,9 +455,8 @@ if $extstatic
 end
 for dir in ["ext", File::join($top_srcdir, "ext")]
   setup = File::join(dir, CONFIG['setup'])
-  if File.file? setup
-    f = open(setup)
-    while line = f.gets()
+  if (f = File.stat(setup) and f.file? rescue next)
+    File.foreach(setup) do |line|
       line.chomp!
       line.sub!(/#.*$/, '')
       next if /^\s*$/ =~ line
@@ -457,7 +473,6 @@ for dir in ["ext", File::join($top_srcdir, "ext")]
     end
     MTIMES << f.mtime
     $setup = setup
-    f.close
     break
   end
 end unless $extstatic
@@ -521,12 +536,20 @@ cond = proc {|ext, *|
 end
 ext_prefix = ext_prefix[$top_srcdir.size+1..-2]
 
+@ext_prefix = ext_prefix
+@inplace = inplace
 extend Module.new {
+
   def timestamp_file(name, target_prefix = nil)
     if @gemname and name == '$(TARGET_SO_DIR)'
-      name = "$(arch)/gems/#{@gemname}#{target_prefix}"
+      gem = true
+      name = "$(gem_platform)/$(ruby_version)/gems/#{@gemname}#{target_prefix}"
+    end
+    path = super.sub(%r[/\.extout\.(?:-\.)?], '/.')
+    if gem
+      nil while path.sub!(%r[/\.(gem_platform|ruby_version)\.-(?=\.)], '/$(\1)/')
     end
-    super.sub(%r[/\.extout\.(?:-\.)?], '/.')
+    path
   end
 
   def configuration(srcdir)
@@ -534,29 +557,81 @@ extend Module.new {
   end
 
   def create_makefile(*args, &block)
-    return super unless @gemname
+    unless @gemname
+      if $static and (target = args.first).include?("/")
+        base = File.basename(target)
+        $defs << "-DInit_#{base}=Init_#{target.tr('/', '_')}"
+      end
+      return super
+    end
     super(*args) do |conf|
       conf.find do |s|
+        s.sub!(%r(^(srcdir *= *)\$\(top_srcdir\)/\.bundle/gems/[^/]+(?=/))) {
+          "gem_#{$&}\n" "#{$1}$(gem_srcdir)"
+        }
+        s.sub!(/^(TIMESTAMP_DIR *= *)\$\(extout\)/) {
+          "TARGET_TOPDIR = $(topdir)/.bundle\n" "#{$1}$(TARGET_TOPDIR)"
+        }
         s.sub!(/^(TARGET_SO_DIR *= *)\$\(RUBYARCHDIR\)/) {
-          "TARGET_GEM_DIR = $(topdir)/.bundle/extensions/$(gem_platform)/$(ruby_version)/#{@gemname}\n"\
+          "TARGET_GEM_DIR = $(TARGET_TOPDIR)/extensions/$(gem_platform)"\
+          "/$(ruby_version)#{$enable_shared ? '' : '-static'}/#{@gemname}\n"\
           "#{$1}$(TARGET_GEM_DIR)$(target_prefix)"
         }
       end
-      conf.any? {|s| /^TARGET *= *\S/ =~ s} and conf << %{
+
+      gemlib = File.directory?("#{$top_srcdir}/#{@ext_prefix}/#{@gemname}/lib")
+      if conf.any? {|s| /^TARGET *= *\S/ =~ s}
+        conf << %{
 gem_platform = #{Gem::Platform.local}
 
 # default target
 all:
 
+gem = #{@gemname}
+
 build_complete = $(TARGET_GEM_DIR)/gem.build_complete
 install-so: build_complete
+clean-so:: clean-build_complete
+
 build_complete: $(build_complete)
 $(build_complete): $(TARGET_SO)
 	$(Q) $(TOUCH) $@
 
-clean-so::
+clean-build_complete:
 	-$(Q)$(RM) $(build_complete)
+
+install: gemspec
+clean: clean-gemspec
+
+gemspec = $(TARGET_TOPDIR)/specifications/$(gem).gemspec
+$(gemspec): $(gem_srcdir)/.bundled.$(gem).gemspec
+	$(Q) $(MAKEDIRS) $(@D)
+	$(Q) $(COPY) $(gem_srcdir)/.bundled.$(gem).gemspec $@
+
+gemspec: $(gemspec)
+
+clean-gemspec:
+	-$(Q)$(RM) $(gemspec)
 }
+
+        if gemlib
+          conf << %{
+install-rb: gemlib
+clean-rb:: clean-gemlib
+
+LN_S = #{config_string('LN_S')}
+CP_R = #{config_string('CP')} -r
+
+gemlib = $(TARGET_TOPDIR)/gems/$(gem)/lib
+gemlib:#{%{ $(gemlib)\n$(gemlib): $(gem_srcdir)/lib} if $nmake}
+	$(Q) #{@inplace ? '$(NULLCMD) ' : ''}$(RUBY) $(top_srcdir)/tool/ln_sr.rb -q -f -T $(gem_srcdir)/lib $(gemlib)
+
+clean-gemlib:
+	$(Q) $(#{@inplace ? 'NULLCMD' : 'RM_RF'}) $(gemlib)
+}
+        end
+      end
+
       conf
     end
   end
@@ -658,6 +733,8 @@ begin
     mf.puts "ECHO1 = $(V:1=@:)"
     mf.puts "ECHO = $(ECHO1:0=@echo)"
     mf.puts "MFLAGS = -$(MAKEFLAGS)" if $nmake
+    mf.puts "override MFLAGS := $(filter-out -j%,$(MFLAGS))" if $gnumake
+    mf.puts "ext_build_dir = #{File.dirname($command_output)}"
     mf.puts
 
     def mf.macro(name, values, max = 70)
@@ -700,6 +777,7 @@ begin
     mf.macro "SUBMAKEOPTS", submakeopts
     mf.macro "NOTE_MESG", %w[$(RUBY) $(top_srcdir)/tool/lib/colorize.rb skip]
     mf.macro "NOTE_NAME", %w[$(RUBY) $(top_srcdir)/tool/lib/colorize.rb fail]
+    %w[RM RMDIRS RMDIR RMALL].each {|w| mf.macro w, [RbConfig::CONFIG[w]]}
     mf.puts
     targets = %w[all install static install-so install-rb clean distclean realclean]
     targets.each do |tgt|
@@ -734,16 +812,20 @@ begin
       exts.each do |d|
         d = d[0..-2]
         t = "#{d}#{tgt}"
-        if  /^(dist|real)?clean$/ =~ tgt
+        if clean = /^(dist|real)?clean$/.match(tgt)
           deps = exts.select {|e|e.start_with?(d)}.map {|e|"#{e[0..-2]}#{tgt}"} - [t]
-          pd = ' ' + deps.join(' ') unless deps.empty?
+          pd = [' clean-local', *deps].join(' ')
         else
           pext = File.dirname(d)
           pd = " #{pext}/#{tgt}" if exts.include?("#{pext}/.")
         end
         mf.puts "#{t}:#{pd}\n\t$(Q)#{submake} $(MFLAGS) V=$(V) $(@F)"
+        if clean and clean.begin(1)
+          mf.puts "\t$(Q)$(RM) $(ext_build_dir)/exts.mk\n\t$(Q)$(RMDIRS) -p $(@D)"
+        end
       end
     end
+    mf.puts "\n""clean-local:\n\t$(Q)$(RM) $(ext_build_dir)/*~ $(ext_build_dir)/*.bak $(ext_build_dir)/core"
     mf.puts "\n""extso:\n"
     mf.puts "\t@echo EXTSO=$(EXTSO)"
 
diff --git a/ext/fcntl/fcntl.gemspec b/ext/fcntl/fcntl.gemspec
index 048e101aa5..09d3fc2568 100644
--- a/ext/fcntl/fcntl.gemspec
+++ b/ext/fcntl/fcntl.gemspec
@@ -3,7 +3,7 @@
 
 Gem::Specification.new do |spec|
   spec.name          = "fcntl"
-  spec.version       = "1.0.1"
+  spec.version       = "1.0.2"
   spec.authors       = ["Yukihiro Matsumoto"]
   spec.email         = ["matz@ruby-lang.org"]
 
diff --git a/ext/fiddle/closure.c b/ext/fiddle/closure.c
index 3679e5c9ad..892f522a62 100644
--- a/ext/fiddle/closure.c
+++ b/ext/fiddle/closure.c
@@ -56,6 +56,8 @@ closure_memsize(const void * ptr)
 const rb_data_type_t closure_data_type = {
     "fiddle/closure",
     {0, dealloc, closure_memsize,},
+    0, 0,
+    RUBY_TYPED_FREE_IMMEDIATELY,
 };
 
 struct callback_args {
@@ -90,7 +92,7 @@ with_gvl_callback(void *ptr)
 	  case TYPE_INT:
 	    rb_ary_push(params, INT2NUM(*(int *)x->args[i]));
 	    break;
-	  case -TYPE_INT:
+	  case TYPE_UINT:
 	    rb_ary_push(params, UINT2NUM(*(unsigned int *)x->args[i]));
 	    break;
 	  case TYPE_VOIDP:
@@ -101,19 +103,19 @@ with_gvl_callback(void *ptr)
 	  case TYPE_LONG:
 	    rb_ary_push(params, LONG2NUM(*(long *)x->args[i]));
 	    break;
-	  case -TYPE_LONG:
+	  case TYPE_ULONG:
 	    rb_ary_push(params, ULONG2NUM(*(unsigned long *)x->args[i]));
 	    break;
 	  case TYPE_CHAR:
 	    rb_ary_push(params, INT2NUM(*(signed char *)x->args[i]));
 	    break;
-	  case -TYPE_CHAR:
+	  case TYPE_UCHAR:
 	    rb_ary_push(params, UINT2NUM(*(unsigned char *)x->args[i]));
 	    break;
 	  case TYPE_SHORT:
 	    rb_ary_push(params, INT2NUM(*(signed short *)x->args[i]));
 	    break;
-	  case -TYPE_SHORT:
+	  case TYPE_USHORT:
 	    rb_ary_push(params, UINT2NUM(*(unsigned short *)x->args[i]));
 	    break;
 	  case TYPE_DOUBLE:
@@ -126,7 +128,7 @@ with_gvl_callback(void *ptr)
 	  case TYPE_LONG_LONG:
 	    rb_ary_push(params, LL2NUM(*(LONG_LONG *)x->args[i]));
 	    break;
-	  case -TYPE_LONG_LONG:
+	  case TYPE_ULONG_LONG:
 	    rb_ary_push(params, ULL2NUM(*(unsigned LONG_LONG *)x->args[i]));
 	    break;
 #endif
@@ -149,7 +151,7 @@ with_gvl_callback(void *ptr)
       case TYPE_LONG:
 	*(long *)x->resp = NUM2LONG(ret);
 	break;
-      case -TYPE_LONG:
+      case TYPE_ULONG:
 	*(unsigned long *)x->resp = NUM2ULONG(ret);
 	break;
       case TYPE_CHAR:
@@ -157,9 +159,9 @@ with_gvl_callback(void *ptr)
       case TYPE_INT:
 	*(ffi_sarg *)x->resp = NUM2INT(ret);
 	break;
-      case -TYPE_CHAR:
-      case -TYPE_SHORT:
-      case -TYPE_INT:
+      case TYPE_UCHAR:
+      case TYPE_USHORT:
+      case TYPE_UINT:
 	*(ffi_arg *)x->resp = NUM2UINT(ret);
 	break;
       case TYPE_VOIDP:
@@ -175,7 +177,7 @@ with_gvl_callback(void *ptr)
       case TYPE_LONG_LONG:
 	*(LONG_LONG *)x->resp = NUM2LL(ret);
 	break;
-      case -TYPE_LONG_LONG:
+      case TYPE_ULONG_LONG:
 	*(unsigned LONG_LONG *)x->resp = NUM2ULL(ret);
 	break;
 #endif
@@ -224,9 +226,27 @@ allocate(VALUE klass)
     return i;
 }
 
+static fiddle_closure *
+get_raw(VALUE self)
+{
+    fiddle_closure *closure;
+    TypedData_Get_Struct(self, fiddle_closure, &closure_data_type, closure);
+    if (!closure) {
+        rb_raise(rb_eArgError, "already freed: %+"PRIsVALUE, self);
+    }
+    return closure;
+}
+
+typedef struct {
+    VALUE self;
+    int argc;
+    VALUE *argv;
+} initialize_data;
+
 static VALUE
-initialize(int rbargc, VALUE argv[], VALUE self)
+initialize_body(VALUE user_data)
 {
+    initialize_data *data = (initialize_data *)user_data;
     VALUE ret;
     VALUE args;
     VALUE normalized_args;
@@ -237,14 +257,14 @@ initialize(int rbargc, VALUE argv[], VALUE self)
     ffi_status result;
     int i, argc;
 
-    if (2 == rb_scan_args(rbargc, argv, "21", &ret, &args, &abi))
-	abi = INT2NUM(FFI_DEFAULT_ABI);
+    if (2 == rb_scan_args(data->argc, data->argv, "21", &ret, &args, &abi))
+        abi = INT2NUM(FFI_DEFAULT_ABI);
 
     Check_Type(args, T_ARRAY);
 
     argc = RARRAY_LENINT(args);
 
-    TypedData_Get_Struct(self, fiddle_closure, &closure_data_type, cl);
+    TypedData_Get_Struct(data->self, fiddle_closure, &closure_data_type, cl);
 
     cl->argv = (ffi_type **)xcalloc(argc + 1, sizeof(ffi_type *));
 
@@ -257,8 +277,8 @@ initialize(int rbargc, VALUE argv[], VALUE self)
     cl->argv[argc] = NULL;
 
     ret = rb_fiddle_type_ensure(ret);
-    rb_iv_set(self, "@ctype", ret);
-    rb_iv_set(self, "@args", normalized_args);
+    rb_iv_set(data->self, "@ctype", ret);
+    rb_iv_set(data->self, "@args", normalized_args);
 
     cif = &cl->cif;
     pcl = cl->pcl;
@@ -269,38 +289,75 @@ initialize(int rbargc, VALUE argv[], VALUE self)
                           rb_fiddle_int_to_ffi_type(NUM2INT(ret)),
                           cl->argv);
 
-    if (FFI_OK != result)
-	rb_raise(rb_eRuntimeError, "error prepping CIF %d", result);
+    if (FFI_OK != result) {
+        rb_raise(rb_eRuntimeError, "error prepping CIF %d", result);
+    }
 
 #if USE_FFI_CLOSURE_ALLOC
     result = ffi_prep_closure_loc(pcl, cif, callback,
-		(void *)self, cl->code);
+                                  (void *)(data->self), cl->code);
 #else
-    result = ffi_prep_closure(pcl, cif, callback, (void *)self);
+    result = ffi_prep_closure(pcl, cif, callback, (void *)(data->self));
     cl->code = (void *)pcl;
     i = mprotect(pcl, sizeof(*pcl), PROT_READ | PROT_EXEC);
     if (i) {
-	rb_sys_fail("mprotect");
+        rb_sys_fail("mprotect");
     }
 #endif
 
-    if (FFI_OK != result)
-	rb_raise(rb_eRuntimeError, "error prepping closure %d", result);
+    if (FFI_OK != result) {
+        rb_raise(rb_eRuntimeError, "error prepping closure %d", result);
+    }
 
-    return self;
+    return data->self;
 }
 
 static VALUE
-to_i(VALUE self)
+initialize_rescue(VALUE user_data, VALUE exception)
 {
-    fiddle_closure * cl;
-    void *code;
+    initialize_data *data = (initialize_data *)user_data;
+    dealloc(RTYPEDDATA_DATA(data->self));
+    RTYPEDDATA_DATA(data->self) = NULL;
+    rb_exc_raise(exception);
+    return data->self;
+}
 
-    TypedData_Get_Struct(self, fiddle_closure, &closure_data_type, cl);
+static VALUE
+initialize(int argc, VALUE *argv, VALUE self)
+{
+    initialize_data data;
+    data.self = self;
+    data.argc = argc;
+    data.argv = argv;
+    return rb_rescue(initialize_body, (VALUE)&data,
+                     initialize_rescue, (VALUE)&data);
+}
 
-    code = cl->code;
+static VALUE
+to_i(VALUE self)
+{
+    fiddle_closure *closure = get_raw(self);
+    return PTR2NUM(closure->code);
+}
 
-    return PTR2NUM(code);
+static VALUE
+closure_free(VALUE self)
+{
+    fiddle_closure *closure;
+    TypedData_Get_Struct(self, fiddle_closure, &closure_data_type, closure);
+    if (closure) {
+        dealloc(closure);
+        RTYPEDDATA_DATA(self) = NULL;
+    }
+    return RUBY_Qnil;
+}
+
+static VALUE
+closure_freed_p(VALUE self)
+{
+    fiddle_closure *closure;
+    TypedData_Get_Struct(self, fiddle_closure, &closure_data_type, closure);
+    return closure ? RUBY_Qfalse : RUBY_Qtrue;
 }
 
 void
@@ -353,8 +410,24 @@ Init_fiddle_closure(void)
     /*
      * Document-method: to_i
      *
-     * Returns the memory address for this closure
+     * Returns the memory address for this closure.
      */
     rb_define_method(cFiddleClosure, "to_i", to_i, 0);
+
+    /*
+     * Document-method: free
+     *
+     * Free this closure explicitly. You can't use this closure anymore.
+     *
+     * If this closure is already freed, this does nothing.
+     */
+    rb_define_method(cFiddleClosure, "free", closure_free, 0);
+
+    /*
+     * Document-method: freed?
+     *
+     * Whether this closure was freed explicitly.
+     */
+    rb_define_method(cFiddleClosure, "freed?", closure_freed_p, 0);
 }
 /* vim: set noet sw=4 sts=4 */
diff --git a/ext/fiddle/conversions.c b/ext/fiddle/conversions.c
index 6e0ce36378..3b70f7de4c 100644
--- a/ext/fiddle/conversions.c
+++ b/ext/fiddle/conversions.c
@@ -211,32 +211,32 @@ rb_fiddle_value_to_generic(int type, VALUE *src, fiddle_generic *dst)
       case TYPE_CHAR:
 	dst->schar = (signed char)NUM2INT(*src);
 	break;
-      case -TYPE_CHAR:
+      case TYPE_UCHAR:
 	dst->uchar = (unsigned char)NUM2UINT(*src);
 	break;
       case TYPE_SHORT:
 	dst->sshort = (unsigned short)NUM2INT(*src);
 	break;
-      case -TYPE_SHORT:
+      case TYPE_USHORT:
 	dst->sshort = (signed short)NUM2UINT(*src);
 	break;
       case TYPE_INT:
 	dst->sint = NUM2INT(*src);
 	break;
-      case -TYPE_INT:
+      case TYPE_UINT:
 	dst->uint = NUM2UINT(*src);
 	break;
       case TYPE_LONG:
 	dst->slong = NUM2LONG(*src);
 	break;
-      case -TYPE_LONG:
+      case TYPE_ULONG:
 	dst->ulong = NUM2ULONG(*src);
 	break;
 #if HAVE_LONG_LONG
       case TYPE_LONG_LONG:
 	dst->slong_long = NUM2LL(*src);
 	break;
-      case -TYPE_LONG_LONG:
+      case TYPE_ULONG_LONG:
 	dst->ulong_long = NUM2ULL(*src);
 	break;
 #endif
@@ -283,24 +283,24 @@ rb_fiddle_generic_to_value(VALUE rettype, fiddle_generic retval)
           PTR2NUM((void *)retval.pointer));
       case TYPE_CHAR:
 	return INT2NUM((signed char)retval.fffi_sarg);
-      case -TYPE_CHAR:
+      case TYPE_UCHAR:
 	return INT2NUM((unsigned char)retval.fffi_arg);
       case TYPE_SHORT:
 	return INT2NUM((signed short)retval.fffi_sarg);
-      case -TYPE_SHORT:
+      case TYPE_USHORT:
 	return INT2NUM((unsigned short)retval.fffi_arg);
       case TYPE_INT:
 	return INT2NUM((signed int)retval.fffi_sarg);
-      case -TYPE_INT:
+      case TYPE_UINT:
 	return UINT2NUM((unsigned int)retval.fffi_arg);
       case TYPE_LONG:
 	return LONG2NUM(retval.slong);
-      case -TYPE_LONG:
+      case TYPE_ULONG:
 	return ULONG2NUM(retval.ulong);
 #if HAVE_LONG_LONG
       case TYPE_LONG_LONG:
 	return LL2NUM(retval.slong_long);
-      case -TYPE_LONG_LONG:
+      case TYPE_ULONG_LONG:
 	return ULL2NUM(retval.ulong_long);
 #endif
       case TYPE_FLOAT:
diff --git a/ext/fiddle/extconf.rb b/ext/fiddle/extconf.rb
index 93b4f9d4fa..cf8b5223bb 100644
--- a/ext/fiddle/extconf.rb
+++ b/ext/fiddle/extconf.rb
@@ -46,7 +46,7 @@ end
 
 libffi_version = nil
 have_libffi = false
-bundle = enable_config('bundled-libffi')
+bundle = with_config("libffi-source-dir")
 unless bundle
   dir_config 'libffi'
 
@@ -67,27 +67,11 @@ unless bundle
 end
 
 unless have_libffi
-  # for https://github.com/ruby/fiddle
-  extlibs_rb = File.expand_path("../../bin/extlibs.rb", $srcdir)
-  if bundle && File.exist?(extlibs_rb)
-    require "fileutils"
-    require_relative "../../bin/extlibs"
-    extlibs = ExtLibs.new
-    cache_dir = File.expand_path("../../tmp/.download_cache", $srcdir)
-    ext_dir = File.expand_path("../../ext", $srcdir)
-    Dir.glob("#{$srcdir}/libffi-*/").each{|dir| FileUtils.rm_rf(dir)}
-    extlibs.run(["--cache=#{cache_dir}", ext_dir])
-  end
-  if bundle != false
-    libffi_package_name = Dir.glob("#{$srcdir}/libffi-*/")
-                            .map {|n| File.basename(n)}
-                            .max_by {|n| n.scan(/\d+/).map(&:to_i)}
-  end
-  unless libffi_package_name
-    raise "missing libffi. Please install libffi."
+  if bundle
+    libffi_srcdir = libffi_package_name = bundle
+  else
+    raise "missing libffi. Please install libffi or use --with-libffi-source-dir with libffi source location."
   end
-
-  libffi_srcdir = "#{$srcdir}/#{libffi_package_name}"
   ffi_header = 'ffi.h'
   libffi = Struct.new(*%I[dir srcdir builddir include lib a cflags ldflags opt arch]).new
   libffi.dir = libffi_package_name
@@ -167,7 +151,7 @@ if libffi_version
   libffi_version = libffi_version.gsub(/-rc\d+/, '')
   libffi_version = (libffi_version.split('.').map(&:to_i) + [0,0])[0,3]
   $defs.push(%{-DRUBY_LIBFFI_MODVERSION=#{ '%d%03d%03d' % libffi_version }})
-  puts "libffi_version: #{libffi_version.join('.')}"
+  warn "libffi_version: #{libffi_version.join('.')}"
 end
 
 case
@@ -226,7 +210,7 @@ types.each do |type, signed|
 end
 
 if libffi
-  $LOCAL_LIBS.prepend("./#{libffi.a} ").strip! # to exts.mk
+  $LOCAL_LIBS.prepend("#{libffi.a} ").strip! # to exts.mk
   $INCFLAGS.gsub!(/-I#{libffi.dir}/, '-I$(LIBFFI_DIR)')
 end
 create_makefile 'fiddle' do |conf|
diff --git a/ext/fiddle/extlibs b/ext/fiddle/extlibs
deleted file mode 100644
index 68dac46a95..0000000000
--- a/ext/fiddle/extlibs
+++ /dev/null
@@ -1,13 +0,0 @@
-ver = 3.2.1
-pkg = libffi-$(ver)
-
-https://ftp.osuosl.org/pub/blfs/conglomeration/libffi/$(pkg).tar.gz \
-  md5:83b89587607e3eb65c70d361f13bab43 \
-  sha512:980ca30a8d76f963fca722432b1fe5af77d7a4e4d2eac5144fbc5374d4c596609a293440573f4294207e1bdd9fda80ad1e1cafb2ffb543df5a275bc3bd546483 \
-  #
-	win32/$(pkg)-mswin.patch -p0
-
-$(pkg)/config.guess -> /tool/config.guess
-$(pkg)/config.sub -> /tool/config.sub
-
-! chdir: $(pkg)| autoconf || exit 0
diff --git a/ext/fiddle/fiddle.c b/ext/fiddle/fiddle.c
index a8b5123269..c06cd5634a 100644
--- a/ext/fiddle/fiddle.c
+++ b/ext/fiddle/fiddle.c
@@ -164,137 +164,193 @@ Init_fiddle(void)
      */
     rb_eFiddleDLError = rb_define_class_under(mFiddle, "DLError", rb_eFiddleError);
 
-    /* Document-const: TYPE_VOID
+    VALUE mFiddleTypes = rb_define_module_under(mFiddle, "Types");
+
+    /* Document-const: Fiddle::Types::VOID
      *
      * C type - void
      */
-    rb_define_const(mFiddle, "TYPE_VOID",      INT2NUM(TYPE_VOID));
+    rb_define_const(mFiddleTypes, "VOID",      INT2NUM(TYPE_VOID));
 
-    /* Document-const: TYPE_VOIDP
+    /* Document-const: Fiddle::Types::VOIDP
      *
      * C type - void*
      */
-    rb_define_const(mFiddle, "TYPE_VOIDP",     INT2NUM(TYPE_VOIDP));
+    rb_define_const(mFiddleTypes, "VOIDP",     INT2NUM(TYPE_VOIDP));
 
-    /* Document-const: TYPE_CHAR
+    /* Document-const: Fiddle::Types::CHAR
      *
      * C type - char
      */
-    rb_define_const(mFiddle, "TYPE_CHAR",      INT2NUM(TYPE_CHAR));
+    rb_define_const(mFiddleTypes, "CHAR",      INT2NUM(TYPE_CHAR));
 
-    /* Document-const: TYPE_SHORT
+    /* Document-const: Fiddle::Types::UCHAR
+     *
+     * C type - unsigned char
+     */
+    rb_define_const(mFiddleTypes, "UCHAR",      INT2NUM(TYPE_UCHAR));
+
+    /* Document-const: Fiddle::Types::SHORT
      *
      * C type - short
      */
-    rb_define_const(mFiddle, "TYPE_SHORT",     INT2NUM(TYPE_SHORT));
+    rb_define_const(mFiddleTypes, "SHORT",     INT2NUM(TYPE_SHORT));
 
-    /* Document-const: TYPE_INT
+    /* Document-const: Fiddle::Types::USHORT
+     *
+     * C type - unsigned short
+     */
+    rb_define_const(mFiddleTypes, "USHORT",     INT2NUM(TYPE_USHORT));
+
+    /* Document-const: Fiddle::Types::INT
      *
      * C type - int
      */
-    rb_define_const(mFiddle, "TYPE_INT",       INT2NUM(TYPE_INT));
+    rb_define_const(mFiddleTypes, "INT",       INT2NUM(TYPE_INT));
+
+    /* Document-const: Fiddle::Types::UINT
+     *
+     * C type - unsigned int
+     */
+    rb_define_const(mFiddleTypes, "UINT",       INT2NUM(TYPE_UINT));
+
+    /* Document-const: Fiddle::Types::LONG
+     *
+     * C type - long
+     */
+    rb_define_const(mFiddleTypes, "LONG",      INT2NUM(TYPE_LONG));
 
-    /* Document-const: TYPE_LONG
+    /* Document-const: Fiddle::Types::ULONG
      *
      * C type - long
      */
-    rb_define_const(mFiddle, "TYPE_LONG",      INT2NUM(TYPE_LONG));
+    rb_define_const(mFiddleTypes, "ULONG",      INT2NUM(TYPE_ULONG));
 
 #if HAVE_LONG_LONG
-    /* Document-const: TYPE_LONG_LONG
+    /* Document-const: Fiddle::Types::LONG_LONG
+     *
+     * C type - long long
+     */
+    rb_define_const(mFiddleTypes, "LONG_LONG", INT2NUM(TYPE_LONG_LONG));
+
+    /* Document-const: Fiddle::Types::ULONG_LONG
      *
      * C type - long long
      */
-    rb_define_const(mFiddle, "TYPE_LONG_LONG", INT2NUM(TYPE_LONG_LONG));
+    rb_define_const(mFiddleTypes, "ULONG_LONG", INT2NUM(TYPE_ULONG_LONG));
 #endif
 
 #ifdef TYPE_INT8_T
-    /* Document-const: TYPE_INT8_T
+    /* Document-const: Fiddle::Types::INT8_T
      *
      * C type - int8_t
      */
-    rb_define_const(mFiddle, "TYPE_INT8_T",    INT2NUM(TYPE_INT8_T));
+    rb_define_const(mFiddleTypes, "INT8_T",    INT2NUM(TYPE_INT8_T));
+
+    /* Document-const: Fiddle::Types::UINT8_T
+     *
+     * C type - uint8_t
+     */
+    rb_define_const(mFiddleTypes, "UINT8_T",    INT2NUM(TYPE_UINT8_T));
 #endif
 
 #ifdef TYPE_INT16_T
-    /* Document-const: TYPE_INT16_T
+    /* Document-const: Fiddle::Types::INT16_T
      *
      * C type - int16_t
      */
-    rb_define_const(mFiddle, "TYPE_INT16_T",   INT2NUM(TYPE_INT16_T));
+    rb_define_const(mFiddleTypes, "INT16_T",   INT2NUM(TYPE_INT16_T));
+
+    /* Document-const: Fiddle::Types::UINT16_T
+     *
+     * C type - uint16_t
+     */
+    rb_define_const(mFiddleTypes, "UINT16_T",   INT2NUM(TYPE_UINT16_T));
 #endif
 
 #ifdef TYPE_INT32_T
-    /* Document-const: TYPE_INT32_T
+    /* Document-const: Fiddle::Types::INT32_T
      *
      * C type - int32_t
      */
-    rb_define_const(mFiddle, "TYPE_INT32_T",   INT2NUM(TYPE_INT32_T));
+    rb_define_const(mFiddleTypes, "INT32_T",   INT2NUM(TYPE_INT32_T));
+
+    /* Document-const: Fiddle::Types::UINT32_T
+     *
+     * C type - uint32_t
+     */
+    rb_define_const(mFiddleTypes, "UINT32_T",   INT2NUM(TYPE_UINT32_T));
 #endif
 
 #ifdef TYPE_INT64_T
-    /* Document-const: TYPE_INT64_T
+    /* Document-const: Fiddle::Types::INT64_T
      *
      * C type - int64_t
      */
-    rb_define_const(mFiddle, "TYPE_INT64_T",   INT2NUM(TYPE_INT64_T));
+    rb_define_const(mFiddleTypes, "INT64_T",   INT2NUM(TYPE_INT64_T));
+
+    /* Document-const: Fiddle::Types::UINT64_T
+     *
+     * C type - uint64_t
+     */
+    rb_define_const(mFiddleTypes, "UINT64_T",   INT2NUM(TYPE_UINT64_T));
 #endif
 
-    /* Document-const: TYPE_FLOAT
+    /* Document-const: Fiddle::Types::FLOAT
      *
      * C type - float
      */
-    rb_define_const(mFiddle, "TYPE_FLOAT",     INT2NUM(TYPE_FLOAT));
+    rb_define_const(mFiddleTypes, "FLOAT",     INT2NUM(TYPE_FLOAT));
 
-    /* Document-const: TYPE_DOUBLE
+    /* Document-const: Fiddle::Types::DOUBLE
      *
      * C type - double
      */
-    rb_define_const(mFiddle, "TYPE_DOUBLE",    INT2NUM(TYPE_DOUBLE));
+    rb_define_const(mFiddleTypes, "DOUBLE",    INT2NUM(TYPE_DOUBLE));
 
 #ifdef HAVE_FFI_PREP_CIF_VAR
-    /* Document-const: TYPE_VARIADIC
+    /* Document-const: Fiddle::Types::VARIADIC
      *
      * C type - ...
      */
-    rb_define_const(mFiddle, "TYPE_VARIADIC",  INT2NUM(TYPE_VARIADIC));
+    rb_define_const(mFiddleTypes, "VARIADIC",  INT2NUM(TYPE_VARIADIC));
 #endif
 
-    /* Document-const: TYPE_CONST_STRING
+    /* Document-const: Fiddle::Types::CONST_STRING
      *
      * C type - const char* ('\0' terminated const char*)
      */
-    rb_define_const(mFiddle, "TYPE_CONST_STRING",  INT2NUM(TYPE_CONST_STRING));
+    rb_define_const(mFiddleTypes, "CONST_STRING",  INT2NUM(TYPE_CONST_STRING));
 
-    /* Document-const: TYPE_SIZE_T
+    /* Document-const: Fiddle::Types::SIZE_T
      *
      * C type - size_t
      */
-    rb_define_const(mFiddle, "TYPE_SIZE_T",   INT2NUM(TYPE_SIZE_T));
+    rb_define_const(mFiddleTypes, "SIZE_T",   INT2NUM(TYPE_SIZE_T));
 
-    /* Document-const: TYPE_SSIZE_T
+    /* Document-const: Fiddle::Types::SSIZE_T
      *
      * C type - ssize_t
      */
-    rb_define_const(mFiddle, "TYPE_SSIZE_T",   INT2NUM(TYPE_SSIZE_T));
+    rb_define_const(mFiddleTypes, "SSIZE_T",   INT2NUM(TYPE_SSIZE_T));
 
-    /* Document-const: TYPE_PTRDIFF_T
+    /* Document-const: Fiddle::Types::PTRDIFF_T
      *
      * C type - ptrdiff_t
      */
-    rb_define_const(mFiddle, "TYPE_PTRDIFF_T", INT2NUM(TYPE_PTRDIFF_T));
+    rb_define_const(mFiddleTypes, "PTRDIFF_T", INT2NUM(TYPE_PTRDIFF_T));
 
-    /* Document-const: TYPE_INTPTR_T
+    /* Document-const: Fiddle::Types::INTPTR_T
      *
      * C type - intptr_t
      */
-    rb_define_const(mFiddle, "TYPE_INTPTR_T",  INT2NUM(TYPE_INTPTR_T));
+    rb_define_const(mFiddleTypes, "INTPTR_T",  INT2NUM(TYPE_INTPTR_T));
 
-    /* Document-const: TYPE_UINTPTR_T
+    /* Document-const: Fiddle::Types::UINTPTR_T
      *
      * C type - uintptr_t
      */
-    rb_define_const(mFiddle, "TYPE_UINTPTR_T",  INT2NUM(TYPE_UINTPTR_T));
+    rb_define_const(mFiddleTypes, "UINTPTR_T",  INT2NUM(TYPE_UINTPTR_T));
 
     /* Document-const: ALIGN_VOIDP
      *
@@ -422,30 +478,60 @@ Init_fiddle(void)
      */
     rb_define_const(mFiddle, "SIZEOF_CHAR",  INT2NUM(sizeof(char)));
 
+    /* Document-const: SIZEOF_UCHAR
+     *
+     * size of a unsigned char
+     */
+    rb_define_const(mFiddle, "SIZEOF_UCHAR",  INT2NUM(sizeof(unsigned char)));
+
     /* Document-const: SIZEOF_SHORT
      *
      * size of a short
      */
     rb_define_const(mFiddle, "SIZEOF_SHORT", INT2NUM(sizeof(short)));
 
+    /* Document-const: SIZEOF_USHORT
+     *
+     * size of a unsigned short
+     */
+    rb_define_const(mFiddle, "SIZEOF_USHORT", INT2NUM(sizeof(unsigned short)));
+
     /* Document-const: SIZEOF_INT
      *
      * size of an int
      */
     rb_define_const(mFiddle, "SIZEOF_INT",   INT2NUM(sizeof(int)));
 
+    /* Document-const: SIZEOF_UINT
+     *
+     * size of an unsigned int
+     */
+    rb_define_const(mFiddle, "SIZEOF_UINT",   INT2NUM(sizeof(unsigned int)));
+
     /* Document-const: SIZEOF_LONG
      *
      * size of a long
      */
     rb_define_const(mFiddle, "SIZEOF_LONG",  INT2NUM(sizeof(long)));
 
+    /* Document-const: SIZEOF_ULONG
+     *
+     * size of a unsigned long
+     */
+    rb_define_const(mFiddle, "SIZEOF_ULONG",  INT2NUM(sizeof(unsigned long)));
+
 #if HAVE_LONG_LONG
     /* Document-const: SIZEOF_LONG_LONG
      *
      * size of a long long
      */
     rb_define_const(mFiddle, "SIZEOF_LONG_LONG",  INT2NUM(sizeof(LONG_LONG)));
+
+    /* Document-const: SIZEOF_ULONG_LONG
+     *
+     * size of a unsigned long long
+     */
+    rb_define_const(mFiddle, "SIZEOF_ULONG_LONG",  INT2NUM(sizeof(unsigned LONG_LONG)));
 #endif
 
     /* Document-const: SIZEOF_INT8_T
@@ -454,24 +540,48 @@ Init_fiddle(void)
      */
     rb_define_const(mFiddle, "SIZEOF_INT8_T",  INT2NUM(sizeof(int8_t)));
 
+    /* Document-const: SIZEOF_UINT8_T
+     *
+     * size of a uint8_t
+     */
+    rb_define_const(mFiddle, "SIZEOF_UINT8_T",  INT2NUM(sizeof(uint8_t)));
+
     /* Document-const: SIZEOF_INT16_T
      *
      * size of a int16_t
      */
     rb_define_const(mFiddle, "SIZEOF_INT16_T", INT2NUM(sizeof(int16_t)));
 
+    /* Document-const: SIZEOF_UINT16_T
+     *
+     * size of a uint16_t
+     */
+    rb_define_const(mFiddle, "SIZEOF_UINT16_T", INT2NUM(sizeof(uint16_t)));
+
     /* Document-const: SIZEOF_INT32_T
      *
      * size of a int32_t
      */
     rb_define_const(mFiddle, "SIZEOF_INT32_T", INT2NUM(sizeof(int32_t)));
 
+    /* Document-const: SIZEOF_UINT32_T
+     *
+     * size of a uint32_t
+     */
+    rb_define_const(mFiddle, "SIZEOF_UINT32_T", INT2NUM(sizeof(uint32_t)));
+
     /* Document-const: SIZEOF_INT64_T
      *
      * size of a int64_t
      */
     rb_define_const(mFiddle, "SIZEOF_INT64_T", INT2NUM(sizeof(int64_t)));
 
+    /* Document-const: SIZEOF_UINT64_T
+     *
+     * size of a uint64_t
+     */
+    rb_define_const(mFiddle, "SIZEOF_UINT64_T", INT2NUM(sizeof(uint64_t)));
+
     /* Document-const: SIZEOF_FLOAT
      *
      * size of a float
@@ -540,6 +650,30 @@ Init_fiddle(void)
     rb_define_module_function(mFiddle, "realloc", rb_fiddle_realloc, 2);
     rb_define_module_function(mFiddle, "free", rb_fiddle_free, 1);
 
+    /* Document-const: Qtrue
+     *
+     * The value of Qtrue
+     */
+    rb_define_const(mFiddle, "Qtrue", INT2NUM(Qtrue));
+
+    /* Document-const: Qfalse
+     *
+     * The value of Qfalse
+     */
+    rb_define_const(mFiddle, "Qfalse", INT2NUM(Qfalse));
+
+    /* Document-const: Qnil
+     *
+     * The value of Qnil
+     */
+    rb_define_const(mFiddle, "Qnil", INT2NUM(Qnil));
+
+    /* Document-const: Qundef
+     *
+     * The value of Qundef
+     */
+    rb_define_const(mFiddle, "Qundef", INT2NUM(Qundef));
+
     Init_fiddle_function();
     Init_fiddle_closure();
     Init_fiddle_handle();
diff --git a/ext/fiddle/fiddle.gemspec b/ext/fiddle/fiddle.gemspec
index a9c0ec4026..878109395b 100644
--- a/ext/fiddle/fiddle.gemspec
+++ b/ext/fiddle/fiddle.gemspec
@@ -20,15 +20,12 @@ Gem::Specification.new do |spec|
     "LICENSE.txt",
     "README.md",
     "Rakefile",
-    "bin/downloader.rb",
-    "bin/extlibs.rb",
     "ext/fiddle/closure.c",
     "ext/fiddle/closure.h",
     "ext/fiddle/conversions.c",
     "ext/fiddle/conversions.h",
     "ext/fiddle/depend",
     "ext/fiddle/extconf.rb",
-    "ext/fiddle/extlibs",
     "ext/fiddle/fiddle.c",
     "ext/fiddle/fiddle.h",
     "ext/fiddle/function.c",
diff --git a/ext/fiddle/fiddle.h b/ext/fiddle/fiddle.h
index 9de62a58cc..10eb9ceedb 100644
--- a/ext/fiddle/fiddle.h
+++ b/ext/fiddle/fiddle.h
@@ -111,11 +111,16 @@
 #define TYPE_VOID  0
 #define TYPE_VOIDP 1
 #define TYPE_CHAR  2
+#define TYPE_UCHAR  -TYPE_CHAR
 #define TYPE_SHORT 3
+#define TYPE_USHORT -TYPE_SHORT
 #define TYPE_INT   4
+#define TYPE_UINT   -TYPE_INT
 #define TYPE_LONG  5
+#define TYPE_ULONG  -TYPE_LONG
 #if HAVE_LONG_LONG
 #define TYPE_LONG_LONG 6
+#define TYPE_ULONG_LONG -TYPE_LONG_LONG
 #endif
 #define TYPE_FLOAT 7
 #define TYPE_DOUBLE 8
@@ -123,11 +128,18 @@
 #define TYPE_CONST_STRING 10
 
 #define TYPE_INT8_T TYPE_CHAR
+#define TYPE_UINT8_T -TYPE_INT8_T
+
 #if SIZEOF_SHORT == 2
 # define TYPE_INT16_T TYPE_SHORT
 #elif SIZEOF_INT == 2
 # define TYPE_INT16_T TYPE_INT
 #endif
+
+#ifdef TYPE_INT16_T
+# define TYPE_UINT16_T -TYPE_INT16_T
+#endif
+
 #if SIZEOF_SHORT == 4
 # define TYPE_INT32_T TYPE_SHORT
 #elif SIZEOF_INT == 4
@@ -135,6 +147,11 @@
 #elif SIZEOF_LONG == 4
 # define TYPE_INT32_T TYPE_LONG
 #endif
+
+#ifdef TYPE_INT32_T
+#define TYPE_UINT32_T -TYPE_INT32_T
+#endif
+
 #if SIZEOF_INT == 8
 # define TYPE_INT64_T TYPE_INT
 #elif SIZEOF_LONG == 8
@@ -143,6 +160,10 @@
 # define TYPE_INT64_T TYPE_LONG_LONG
 #endif
 
+#ifdef TYPE_INT64_T
+#define TYPE_UINT64_T -TYPE_INT64_T
+#endif
+
 #ifndef TYPE_SSIZE_T
 # if SIZEOF_SIZE_T == SIZEOF_INT
 #   define TYPE_SSIZE_T TYPE_INT
diff --git a/ext/fiddle/handle.c b/ext/fiddle/handle.c
index 76b90909d3..ae8cc3a581 100644
--- a/ext/fiddle/handle.c
+++ b/ext/fiddle/handle.c
@@ -321,8 +321,10 @@ rb_fiddle_handle_s_sym(VALUE self, VALUE sym)
     return fiddle_handle_sym(RTLD_NEXT, sym);
 }
 
-static VALUE
-fiddle_handle_sym(void *handle, VALUE symbol)
+typedef void (*fiddle_void_func)(void);
+
+static fiddle_void_func
+fiddle_handle_find_func(void *handle, VALUE symbol)
 {
 #if defined(HAVE_DLERROR)
     const char *err;
@@ -330,13 +332,13 @@ fiddle_handle_sym(void *handle, VALUE symbol)
 #else
 # define CHECK_DLERROR
 #endif
-    void (*func)();
+    fiddle_void_func func;
     const char *name = StringValueCStr(symbol);
 
 #ifdef HAVE_DLERROR
     dlerror();
 #endif
-    func = (void (*)())(VALUE)dlsym(handle, name);
+    func = (fiddle_void_func)(VALUE)dlsym(handle, name);
     CHECK_DLERROR;
 #if defined(FUNC_STDCALL)
     if( !func ){
@@ -379,6 +381,53 @@ fiddle_handle_sym(void *handle, VALUE symbol)
 	xfree(name_n);
     }
 #endif
+
+    return func;
+}
+
+static VALUE
+rb_fiddle_handle_s_sym_defined(VALUE self, VALUE sym)
+{
+    fiddle_void_func func;
+
+    func = fiddle_handle_find_func(RTLD_NEXT, sym);
+
+    if( func ) {
+	return PTR2NUM(func);
+    }
+    else {
+	return Qnil;
+    }
+}
+
+static VALUE
+rb_fiddle_handle_sym_defined(VALUE self, VALUE sym)
+{
+    struct dl_handle *fiddle_handle;
+    fiddle_void_func func;
+
+    TypedData_Get_Struct(self, struct dl_handle, &fiddle_handle_data_type, fiddle_handle);
+    if( ! fiddle_handle->open ){
+	rb_raise(rb_eFiddleDLError, "closed handle");
+    }
+
+    func = fiddle_handle_find_func(fiddle_handle->ptr, sym);
+
+    if( func ) {
+	return PTR2NUM(func);
+    }
+    else {
+	return Qnil;
+    }
+}
+
+static VALUE
+fiddle_handle_sym(void *handle, VALUE symbol)
+{
+    fiddle_void_func func;
+
+    func = fiddle_handle_find_func(handle, symbol);
+
     if( !func ){
 	rb_raise(rb_eFiddleDLError, "unknown symbol \"%"PRIsVALUE"\"", symbol);
     }
@@ -468,6 +517,7 @@ Init_fiddle_handle(void)
     rb_cHandle = rb_define_class_under(mFiddle, "Handle", rb_cObject);
     rb_define_alloc_func(rb_cHandle, rb_fiddle_handle_s_allocate);
     rb_define_singleton_method(rb_cHandle, "sym", rb_fiddle_handle_s_sym, 1);
+    rb_define_singleton_method(rb_cHandle, "sym_defined?", rb_fiddle_handle_s_sym_defined, 1);
     rb_define_singleton_method(rb_cHandle, "[]", rb_fiddle_handle_s_sym,  1);
 
     /* Document-const: NEXT
@@ -526,6 +576,7 @@ Init_fiddle_handle(void)
     rb_define_method(rb_cHandle, "close", rb_fiddle_handle_close, 0);
     rb_define_method(rb_cHandle, "sym",  rb_fiddle_handle_sym, 1);
     rb_define_method(rb_cHandle, "[]",  rb_fiddle_handle_sym,  1);
+    rb_define_method(rb_cHandle, "sym_defined?", rb_fiddle_handle_sym_defined, 1);
     rb_define_method(rb_cHandle, "file_name", rb_fiddle_handle_file_name, 0);
     rb_define_method(rb_cHandle, "disable_close", rb_fiddle_handle_disable_close, 0);
     rb_define_method(rb_cHandle, "enable_close", rb_fiddle_handle_enable_close, 0);
diff --git a/ext/fiddle/lib/fiddle.rb b/ext/fiddle/lib/fiddle.rb
index 4512989310..6137c487c6 100644
--- a/ext/fiddle/lib/fiddle.rb
+++ b/ext/fiddle/lib/fiddle.rb
@@ -58,7 +58,36 @@ module Fiddle
   #
   # See Fiddle::Handle.new for more.
   def dlopen library
-    Fiddle::Handle.new library
+    begin
+      Fiddle::Handle.new(library)
+    rescue DLError => error
+      case RUBY_PLATFORM
+      when /linux/
+        case error.message
+        when /\A(\/.+?): (?:invalid ELF header|file too short)/
+          # This may be a linker script:
+          # https://sourceware.org/binutils/docs/ld.html#Scripts
+          path = $1
+        else
+          raise
+        end
+      else
+        raise
+      end
+
+      File.open(path) do |input|
+        input.each_line do |line|
+          case line
+          when /\A\s*(?:INPUT|GROUP)\s*\(\s*([^\s,\)]+)/
+            # TODO: Should we support multiple files?
+            return dlopen($1)
+          end
+        end
+      end
+
+      # Not found
+      raise
+    end
   end
   module_function :dlopen
 
@@ -67,4 +96,8 @@ module Fiddle
   RTLD_GLOBAL = Handle::RTLD_GLOBAL # :nodoc:
   RTLD_LAZY   = Handle::RTLD_LAZY   # :nodoc:
   RTLD_NOW    = Handle::RTLD_NOW    # :nodoc:
+
+  Fiddle::Types.constants.each do |type|
+    const_set "TYPE_#{type}", Fiddle::Types.const_get(type)
+  end
 end
diff --git a/ext/fiddle/lib/fiddle/closure.rb b/ext/fiddle/lib/fiddle/closure.rb
index c865a63c20..7e0077ea52 100644
--- a/ext/fiddle/lib/fiddle/closure.rb
+++ b/ext/fiddle/lib/fiddle/closure.rb
@@ -1,6 +1,31 @@
 # frozen_string_literal: true
 module Fiddle
   class Closure
+    class << self
+      # Create a new closure. If a block is given, the created closure
+      # is automatically freed after the given block is executed.
+      #
+      # The all given arguments are passed to Fiddle::Closure.new. So
+      # using this method without block equals to Fiddle::Closure.new.
+      #
+      # == Example
+      #
+      #   Fiddle::Closure.create(TYPE_INT, [TYPE_INT]) do |closure|
+      #     # closure is freed automatically when this block is finished.
+      #   end
+      def create(*args)
+        if block_given?
+          closure = new(*args)
+          begin
+            yield(closure)
+          ensure
+            closure.free
+          end
+        else
+          new(*args)
+        end
+      end
+    end
 
     # the C type of the return of the FFI closure
     attr_reader :ctype
diff --git a/ext/fiddle/lib/fiddle/cparser.rb b/ext/fiddle/lib/fiddle/cparser.rb
index 93a05513c9..9a70402953 100644
--- a/ext/fiddle/lib/fiddle/cparser.rb
+++ b/ext/fiddle/lib/fiddle/cparser.rb
@@ -164,23 +164,23 @@ module Fiddle
         unless Fiddle.const_defined?(:TYPE_LONG_LONG)
           raise(RuntimeError, "unsupported type: #{ty}")
         end
-        return -TYPE_LONG_LONG
+        return TYPE_ULONG_LONG
       when /\A(?:signed\s+)?long(?:\s+int\s+)?(?:\s+\w+)?\z/
         return TYPE_LONG
       when /\Aunsigned\s+long(?:\s+int\s+)?(?:\s+\w+)?\z/
-        return -TYPE_LONG
+        return TYPE_ULONG
       when /\A(?:signed\s+)?int(?:\s+\w+)?\z/
         return TYPE_INT
       when /\A(?:unsigned\s+int|uint)(?:\s+\w+)?\z/
-        return -TYPE_INT
+        return TYPE_UINT
       when /\A(?:signed\s+)?short(?:\s+int\s+)?(?:\s+\w+)?\z/
         return TYPE_SHORT
       when /\Aunsigned\s+short(?:\s+int\s+)?(?:\s+\w+)?\z/
-        return -TYPE_SHORT
+        return TYPE_USHORT
       when /\A(?:signed\s+)?char(?:\s+\w+)?\z/
         return TYPE_CHAR
       when /\Aunsigned\s+char(?:\s+\w+)?\z/
-        return  -TYPE_CHAR
+        return  TYPE_UCHAR
       when /\Aint8_t(?:\s+\w+)?\z/
         unless Fiddle.const_defined?(:TYPE_INT8_T)
           raise(RuntimeError, "unsupported type: #{ty}")
@@ -190,7 +190,7 @@ module Fiddle
         unless Fiddle.const_defined?(:TYPE_INT8_T)
           raise(RuntimeError, "unsupported type: #{ty}")
         end
-        return -TYPE_INT8_T
+        return TYPE_UINT8_T
       when /\Aint16_t(?:\s+\w+)?\z/
         unless Fiddle.const_defined?(:TYPE_INT16_T)
           raise(RuntimeError, "unsupported type: #{ty}")
@@ -200,7 +200,7 @@ module Fiddle
         unless Fiddle.const_defined?(:TYPE_INT16_T)
           raise(RuntimeError, "unsupported type: #{ty}")
         end
-        return -TYPE_INT16_T
+        return TYPE_UINT16_T
       when /\Aint32_t(?:\s+\w+)?\z/
         unless Fiddle.const_defined?(:TYPE_INT32_T)
           raise(RuntimeError, "unsupported type: #{ty}")
@@ -210,7 +210,7 @@ module Fiddle
         unless Fiddle.const_defined?(:TYPE_INT32_T)
           raise(RuntimeError, "unsupported type: #{ty}")
         end
-        return -TYPE_INT32_T
+        return TYPE_UINT32_T
       when /\Aint64_t(?:\s+\w+)?\z/
         unless Fiddle.const_defined?(:TYPE_INT64_T)
           raise(RuntimeError, "unsupported type: #{ty}")
@@ -220,7 +220,7 @@ module Fiddle
         unless Fiddle.const_defined?(:TYPE_INT64_T)
           raise(RuntimeError, "unsupported type: #{ty}")
         end
-        return -TYPE_INT64_T
+        return TYPE_UINT64_T
       when /\Afloat(?:\s+\w+)?\z/
         return TYPE_FLOAT
       when /\Adouble(?:\s+\w+)?\z/
diff --git a/ext/fiddle/lib/fiddle/pack.rb b/ext/fiddle/lib/fiddle/pack.rb
index 22eccedb76..545b985d50 100644
--- a/ext/fiddle/lib/fiddle/pack.rb
+++ b/ext/fiddle/lib/fiddle/pack.rb
@@ -11,24 +11,24 @@ module Fiddle
       TYPE_LONG  => ALIGN_LONG,
       TYPE_FLOAT => ALIGN_FLOAT,
       TYPE_DOUBLE => ALIGN_DOUBLE,
-      -TYPE_CHAR  => ALIGN_CHAR,
-      -TYPE_SHORT => ALIGN_SHORT,
-      -TYPE_INT   => ALIGN_INT,
-      -TYPE_LONG  => ALIGN_LONG,
+      TYPE_UCHAR  => ALIGN_CHAR,
+      TYPE_USHORT => ALIGN_SHORT,
+      TYPE_UINT   => ALIGN_INT,
+      TYPE_ULONG  => ALIGN_LONG,
     }
 
     PACK_MAP = {
-      TYPE_VOIDP => "l!",
+      TYPE_VOIDP => "L!",
       TYPE_CHAR  => "c",
       TYPE_SHORT => "s!",
       TYPE_INT   => "i!",
       TYPE_LONG  => "l!",
       TYPE_FLOAT => "f",
       TYPE_DOUBLE => "d",
-      -TYPE_CHAR  => "c",
-      -TYPE_SHORT => "s!",
-      -TYPE_INT   => "i!",
-      -TYPE_LONG  => "l!",
+      TYPE_UCHAR  => "C",
+      TYPE_USHORT => "S!",
+      TYPE_UINT   => "I!",
+      TYPE_ULONG  => "L!",
     }
 
     SIZE_MAP = {
@@ -39,16 +39,17 @@ module Fiddle
       TYPE_LONG  => SIZEOF_LONG,
       TYPE_FLOAT => SIZEOF_FLOAT,
       TYPE_DOUBLE => SIZEOF_DOUBLE,
-      -TYPE_CHAR  => SIZEOF_CHAR,
-      -TYPE_SHORT => SIZEOF_SHORT,
-      -TYPE_INT   => SIZEOF_INT,
-      -TYPE_LONG  => SIZEOF_LONG,
+      TYPE_UCHAR  => SIZEOF_CHAR,
+      TYPE_USHORT => SIZEOF_SHORT,
+      TYPE_UINT   => SIZEOF_INT,
+      TYPE_ULONG  => SIZEOF_LONG,
     }
     if defined?(TYPE_LONG_LONG)
-      ALIGN_MAP[TYPE_LONG_LONG] = ALIGN_MAP[-TYPE_LONG_LONG] = ALIGN_LONG_LONG
-      PACK_MAP[TYPE_LONG_LONG] = PACK_MAP[-TYPE_LONG_LONG] = "q"
-      SIZE_MAP[TYPE_LONG_LONG] = SIZE_MAP[-TYPE_LONG_LONG] = SIZEOF_LONG_LONG
-      PACK_MAP[TYPE_VOIDP] = "q" if SIZEOF_LONG_LONG == SIZEOF_VOIDP
+      ALIGN_MAP[TYPE_LONG_LONG] = ALIGN_MAP[TYPE_ULONG_LONG] = ALIGN_LONG_LONG
+      PACK_MAP[TYPE_LONG_LONG] = "q"
+      PACK_MAP[TYPE_ULONG_LONG] = "Q"
+      SIZE_MAP[TYPE_LONG_LONG] = SIZE_MAP[TYPE_ULONG_LONG] = SIZEOF_LONG_LONG
+      PACK_MAP[TYPE_VOIDP] = "Q" if SIZEOF_LONG_LONG == SIZEOF_VOIDP
     end
 
     def align(addr, align)
diff --git a/ext/fiddle/lib/fiddle/version.rb b/ext/fiddle/lib/fiddle/version.rb
index db6504b650..719dc62e37 100644
--- a/ext/fiddle/lib/fiddle/version.rb
+++ b/ext/fiddle/lib/fiddle/version.rb
@@ -1,3 +1,3 @@
 module Fiddle
-  VERSION = "1.1.0"
+  VERSION = "1.1.1"
 end
diff --git a/ext/io/console/console.c b/ext/io/console/console.c
index 4ec24178c4..21454a73fa 100644
--- a/ext/io/console/console.c
+++ b/ext/io/console/console.c
@@ -75,7 +75,7 @@ getattr(int fd, conmode *t)
 #define SET_LAST_ERROR (0)
 #endif
 
-static ID id_getc, id_console, id_close, id_min, id_time, id_intr;
+static ID id_getc, id_console, id_close;
 #if ENABLE_IO_GETPASS
 static ID id_gets, id_chomp_bang;
 #endif
@@ -112,18 +112,34 @@ rb_f_send(int argc, VALUE *argv, VALUE recv)
 }
 #endif
 
+enum rawmode_opt_ids {
+    kwd_min,
+    kwd_time,
+    kwd_intr,
+    rawmode_opt_id_count
+};
+static ID rawmode_opt_ids[rawmode_opt_id_count];
+
 typedef struct {
     int vmin;
     int vtime;
     int intr;
 } rawmode_arg_t;
 
+#ifndef UNDEF_P
+# define UNDEF_P(obj) ((obj) == Qundef)
+#endif
+#ifndef NIL_OR_UNDEF_P
+# define NIL_OR_UNDEF_P(obj) (NIL_P(obj) || UNDEF_P(obj))
+#endif
+
 static rawmode_arg_t *
 rawmode_opt(int *argcp, VALUE *argv, int min_argc, int max_argc, rawmode_arg_t *opts)
 {
     int argc = *argcp;
     rawmode_arg_t *optp = NULL;
     VALUE vopts = Qnil;
+    VALUE optvals[rawmode_opt_id_count];
 #ifdef RB_SCAN_ARGS_PASS_CALLED_KEYWORDS
     argc = rb_scan_args(argc, argv, "*:", NULL, &vopts);
 #else
@@ -138,19 +154,20 @@ rawmode_opt(int *argcp, VALUE *argv, int min_argc, int max_argc, rawmode_arg_t *
     }
 #endif
     rb_check_arity(argc, min_argc, max_argc);
-    if (!NIL_P(vopts)) {
-	VALUE vmin = rb_hash_aref(vopts, ID2SYM(id_min));
-	VALUE vtime = rb_hash_aref(vopts, ID2SYM(id_time));
-	VALUE intr = rb_hash_aref(vopts, ID2SYM(id_intr));
+    if (rb_get_kwargs(vopts, rawmode_opt_ids,
+		      0, rawmode_opt_id_count, optvals)) {
+	VALUE vmin = optvals[kwd_min];
+	VALUE vtime = optvals[kwd_time];
+	VALUE intr = optvals[kwd_intr];
 	/* default values by `stty raw` */
 	opts->vmin = 1;
 	opts->vtime = 0;
 	opts->intr = 0;
-	if (!NIL_P(vmin)) {
+	if (!NIL_OR_UNDEF_P(vmin)) {
 	    opts->vmin = NUM2INT(vmin);
 	    optp = opts;
 	}
-	if (!NIL_P(vtime)) {
+	if (!NIL_OR_UNDEF_P(vtime)) {
 	    VALUE v10 = INT2FIX(10);
 	    vtime = rb_funcall3(vtime, '*', 1, &v10);
 	    opts->vtime = NUM2INT(vtime);
@@ -165,6 +182,7 @@ rawmode_opt(int *argcp, VALUE *argv, int min_argc, int max_argc, rawmode_arg_t *
 	    opts->intr = 0;
 	    optp = opts;
 	    break;
+	  case Qundef:
 	  case Qnil:
 	    break;
 	  default:
@@ -1633,9 +1651,11 @@ Init_console(void)
 #endif
     id_console = rb_intern("console");
     id_close = rb_intern("close");
-    id_min = rb_intern("min");
-    id_time = rb_intern("time");
-    id_intr = rb_intern("intr");
+#define init_rawmode_opt_id(name) \
+    rawmode_opt_ids[kwd_##name] = rb_intern(#name)
+    init_rawmode_opt_id(min);
+    init_rawmode_opt_id(time);
+    init_rawmode_opt_id(intr);
 #ifndef HAVE_RB_F_SEND
     id___send__ = rb_intern("__send__");
 #endif
diff --git a/ext/io/console/depend b/ext/io/console/depend
index 06ccdde70d..36747ef583 100644
--- a/ext/io/console/depend
+++ b/ext/io/console/depend
@@ -185,7 +185,7 @@ win32_vk.inc: win32_vk.list
 	-e 'n=$$F[1] and (n.strip!; /\AVK_/=~n) and' \
 	-e   'puts(%[#ifndef #{n}\n# define #{n} UNDEFINED_VK\n#endif])' \
 	$< && \
-	gperf --ignore-case -E -C -P -p -j1 -i 1 -g -o -t -K ofs -N console_win32_vk -k* $< \
+	gperf --ignore-case -L ANSI-C -E -C -P -p -j1 -i 1 -g -o -t -K ofs -N console_win32_vk -k* $< \
 	| sed -f $(top_srcdir)/tool/gperf.sed \
 	) > $(@F)
 
diff --git a/ext/io/console/io-console.gemspec b/ext/io/console/io-console.gemspec
index aa57f8ac52..d26a757b01 100644
--- a/ext/io/console/io-console.gemspec
+++ b/ext/io/console/io-console.gemspec
@@ -1,5 +1,5 @@
 # -*- ruby -*-
-_VERSION = "0.5.11"
+_VERSION = "0.6.0"
 
 Gem::Specification.new do |s|
   s.name = "io-console"
diff --git a/ext/io/console/win32_vk.inc b/ext/io/console/win32_vk.inc
index cbec7bef15..d15b1219fb 100644
--- a/ext/io/console/win32_vk.inc
+++ b/ext/io/console/win32_vk.inc
@@ -480,7 +480,7 @@
 # define VK_OEM_CLEAR UNDEFINED_VK
 #endif
 /* ANSI-C code produced by gperf version 3.1 */
-/* Command-line: gperf --ignore-case -E -C -P -p -j1 -i 1 -g -o -t -K ofs -N console_win32_vk -k'*' win32_vk.list  */
+/* Command-line: gperf --ignore-case -L ANSI-C -E -C -P -p -j1 -i 1 -g -o -t -K ofs -N console_win32_vk -k'*' win32_vk.list  */
 
 #if !((' ' == 32) && ('!' == 33) && ('"' == 34) && ('#' == 35) \
       && ('%' == 37) && ('&' == 38) && ('\'' == 39) && ('(' == 40) \
@@ -509,18 +509,17 @@
 #error "gperf generated tables don't work with this execution character set. Please report a bug to <bug-gperf@gnu.org>."
 #endif
 
-#define gperf_offsetof(s, n) (short)offsetof(struct s##_t, s##_str##n)
 #line 1 "win32_vk.list"
 
 struct vktable {short ofs; unsigned short vk;};
-static const struct vktable *console_win32_vk(/*const char *, unsigned int*/);
+static const struct vktable *console_win32_vk(const char *, size_t);
 #line 5 "win32_vk.list"
 struct vktable;
 /* maximum key range = 245, duplicates = 0 */
 
 #ifndef GPERF_DOWNCASE
 #define GPERF_DOWNCASE 1
-static unsigned char gperf_downcase[256] =
+static const unsigned char gperf_downcase[256] =
   {
       0,   1,   2,   3,   4,   5,   6,   7,   8,   9,  10,  11,  12,  13,  14,
      15,  16,  17,  18,  19,  20,  21,  22,  23,  24,  25,  26,  27,  28,  29,
@@ -1007,368 +1006,368 @@ console_win32_vk (register const char *str, register size_t len)
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1},
 #line 40 "win32_vk.list"
-      {gperf_offsetof(stringpool, 12), VK_UP},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str12, VK_UP},
 #line 52 "win32_vk.list"
-      {gperf_offsetof(stringpool, 13), VK_APPS},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str13, VK_APPS},
 #line 159 "win32_vk.list"
-      {gperf_offsetof(stringpool, 14), VK_CRSEL},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str14, VK_CRSEL},
 #line 34 "win32_vk.list"
-      {gperf_offsetof(stringpool, 15), VK_SPACE},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str15, VK_SPACE},
 #line 95 "win32_vk.list"
-      {gperf_offsetof(stringpool, 16), VK_SCROLL},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str16, VK_SCROLL},
 #line 29 "win32_vk.list"
-      {gperf_offsetof(stringpool, 17), VK_ESCAPE},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str17, VK_ESCAPE},
 #line 9 "win32_vk.list"
-      {gperf_offsetof(stringpool, 18), VK_CANCEL},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str18, VK_CANCEL},
 #line 32 "win32_vk.list"
-      {gperf_offsetof(stringpool, 19), VK_ACCEPT},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str19, VK_ACCEPT},
 #line 66 "win32_vk.list"
-      {gperf_offsetof(stringpool, 20), VK_SEPARATOR},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str20, VK_SEPARATOR},
 #line 43 "win32_vk.list"
-      {gperf_offsetof(stringpool, 21), VK_SELECT},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str21, VK_SELECT},
 #line 18 "win32_vk.list"
-      {gperf_offsetof(stringpool, 22), VK_CONTROL},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str22, VK_CONTROL},
 #line 166 "win32_vk.list"
-      {gperf_offsetof(stringpool, 23), VK_OEM_CLEAR},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str23, VK_OEM_CLEAR},
 #line 145 "win32_vk.list"
-      {gperf_offsetof(stringpool, 24), VK_OEM_RESET},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str24, VK_OEM_RESET},
 #line 155 "win32_vk.list"
-      {gperf_offsetof(stringpool, 25), VK_OEM_AUTO},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str25, VK_OEM_AUTO},
 #line 151 "win32_vk.list"
-      {gperf_offsetof(stringpool, 26), VK_OEM_CUSEL},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str26, VK_OEM_CUSEL},
       {-1},
 #line 22 "win32_vk.list"
-      {gperf_offsetof(stringpool, 28), VK_KANA},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str28, VK_KANA},
 #line 127 "win32_vk.list"
-      {gperf_offsetof(stringpool, 29), VK_OEM_PLUS},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str29, VK_OEM_PLUS},
 #line 35 "win32_vk.list"
-      {gperf_offsetof(stringpool, 30), VK_PRIOR},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str30, VK_PRIOR},
 #line 152 "win32_vk.list"
-      {gperf_offsetof(stringpool, 31), VK_OEM_ATTN},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str31, VK_OEM_ATTN},
 #line 20 "win32_vk.list"
-      {gperf_offsetof(stringpool, 32), VK_PAUSE},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str32, VK_PAUSE},
 #line 13 "win32_vk.list"
-      {gperf_offsetof(stringpool, 33), VK_BACK},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str33, VK_BACK},
 #line 144 "win32_vk.list"
-      {gperf_offsetof(stringpool, 34), VK_PACKET},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str34, VK_PACKET},
 #line 105 "win32_vk.list"
-      {gperf_offsetof(stringpool, 35), VK_RCONTROL},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str35, VK_RCONTROL},
 #line 104 "win32_vk.list"
-      {gperf_offsetof(stringpool, 36), VK_LCONTROL},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str36, VK_LCONTROL},
 #line 37 "win32_vk.list"
-      {gperf_offsetof(stringpool, 37), VK_END},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str37, VK_END},
 #line 38 "win32_vk.list"
-      {gperf_offsetof(stringpool, 38), VK_HOME},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str38, VK_HOME},
 #line 44 "win32_vk.list"
-      {gperf_offsetof(stringpool, 39), VK_PRINT},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str39, VK_PRINT},
 #line 94 "win32_vk.list"
-      {gperf_offsetof(stringpool, 40), VK_NUMLOCK},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str40, VK_NUMLOCK},
 #line 39 "win32_vk.list"
-      {gperf_offsetof(stringpool, 41), VK_LEFT},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str41, VK_LEFT},
 #line 25 "win32_vk.list"
-      {gperf_offsetof(stringpool, 42), VK_JUNJA},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str42, VK_JUNJA},
 #line 19 "win32_vk.list"
-      {gperf_offsetof(stringpool, 43), VK_MENU},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str43, VK_MENU},
 #line 150 "win32_vk.list"
-      {gperf_offsetof(stringpool, 44), VK_OEM_WSCTRL},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str44, VK_OEM_WSCTRL},
 #line 156 "win32_vk.list"
-      {gperf_offsetof(stringpool, 45), VK_OEM_ENLW},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str45, VK_OEM_ENLW},
 #line 36 "win32_vk.list"
-      {gperf_offsetof(stringpool, 46), VK_NEXT},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str46, VK_NEXT},
 #line 51 "win32_vk.list"
-      {gperf_offsetof(stringpool, 47), VK_RWIN},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str47, VK_RWIN},
 #line 50 "win32_vk.list"
-      {gperf_offsetof(stringpool, 48), VK_LWIN},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str48, VK_LWIN},
 #line 21 "win32_vk.list"
-      {gperf_offsetof(stringpool, 49), VK_CAPITAL},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str49, VK_CAPITAL},
 #line 49 "win32_vk.list"
-      {gperf_offsetof(stringpool, 50), VK_HELP},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str50, VK_HELP},
 #line 164 "win32_vk.list"
-      {gperf_offsetof(stringpool, 51), VK_NONAME},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str51, VK_NONAME},
 #line 8 "win32_vk.list"
-      {gperf_offsetof(stringpool, 52), VK_RBUTTON},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str52, VK_RBUTTON},
 #line 7 "win32_vk.list"
-      {gperf_offsetof(stringpool, 53), VK_LBUTTON},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str53, VK_LBUTTON},
 #line 96 "win32_vk.list"
-      {gperf_offsetof(stringpool, 54), VK_OEM_NEC_EQUAL},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str54, VK_OEM_NEC_EQUAL},
       {-1},
 #line 47 "win32_vk.list"
-      {gperf_offsetof(stringpool, 56), VK_INSERT},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str56, VK_INSERT},
 #line 27 "win32_vk.list"
-      {gperf_offsetof(stringpool, 57), VK_HANJA},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str57, VK_HANJA},
       {-1}, {-1},
 #line 46 "win32_vk.list"
-      {gperf_offsetof(stringpool, 60), VK_SNAPSHOT},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str60, VK_SNAPSHOT},
 #line 158 "win32_vk.list"
-      {gperf_offsetof(stringpool, 61), VK_ATTN},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str61, VK_ATTN},
 #line 14 "win32_vk.list"
-      {gperf_offsetof(stringpool, 62), VK_TAB},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str62, VK_TAB},
 #line 157 "win32_vk.list"
-      {gperf_offsetof(stringpool, 63), VK_OEM_BACKTAB},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str63, VK_OEM_BACKTAB},
 #line 143 "win32_vk.list"
-      {gperf_offsetof(stringpool, 64), VK_ICO_CLEAR},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str64, VK_ICO_CLEAR},
 #line 30 "win32_vk.list"
-      {gperf_offsetof(stringpool, 65), VK_CONVERT},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str65, VK_CONVERT},
 #line 16 "win32_vk.list"
-      {gperf_offsetof(stringpool, 66), VK_RETURN},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str66, VK_RETURN},
 #line 146 "win32_vk.list"
-      {gperf_offsetof(stringpool, 67), VK_OEM_JUMP},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str67, VK_OEM_JUMP},
       {-1}, {-1}, {-1},
 #line 111 "win32_vk.list"
-      {gperf_offsetof(stringpool, 71), VK_BROWSER_STOP},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str71, VK_BROWSER_STOP},
 #line 26 "win32_vk.list"
-      {gperf_offsetof(stringpool, 72), VK_FINAL},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str72, VK_FINAL},
 #line 163 "win32_vk.list"
-      {gperf_offsetof(stringpool, 73), VK_ZOOM},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str73, VK_ZOOM},
 #line 28 "win32_vk.list"
-      {gperf_offsetof(stringpool, 74), VK_KANJI},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str74, VK_KANJI},
 #line 48 "win32_vk.list"
-      {gperf_offsetof(stringpool, 75), VK_DELETE},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str75, VK_DELETE},
 #line 128 "win32_vk.list"
-      {gperf_offsetof(stringpool, 76), VK_OEM_COMMA},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str76, VK_OEM_COMMA},
 #line 67 "win32_vk.list"
-      {gperf_offsetof(stringpool, 77), VK_SUBTRACT},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str77, VK_SUBTRACT},
       {-1},
 #line 10 "win32_vk.list"
-      {gperf_offsetof(stringpool, 79), VK_MBUTTON},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str79, VK_MBUTTON},
 #line 78 "win32_vk.list"
-      {gperf_offsetof(stringpool, 80), VK_F9},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str80, VK_F9},
 #line 17 "win32_vk.list"
-      {gperf_offsetof(stringpool, 81), VK_SHIFT},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str81, VK_SHIFT},
 #line 103 "win32_vk.list"
-      {gperf_offsetof(stringpool, 82), VK_RSHIFT},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str82, VK_RSHIFT},
 #line 102 "win32_vk.list"
-      {gperf_offsetof(stringpool, 83), VK_LSHIFT},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str83, VK_LSHIFT},
 #line 65 "win32_vk.list"
-      {gperf_offsetof(stringpool, 84), VK_ADD},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str84, VK_ADD},
 #line 31 "win32_vk.list"
-      {gperf_offsetof(stringpool, 85), VK_NONCONVERT},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str85, VK_NONCONVERT},
 #line 160 "win32_vk.list"
-      {gperf_offsetof(stringpool, 86), VK_EXSEL},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str86, VK_EXSEL},
 #line 126 "win32_vk.list"
-      {gperf_offsetof(stringpool, 87), VK_OEM_1},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str87, VK_OEM_1},
 #line 138 "win32_vk.list"
-      {gperf_offsetof(stringpool, 88), VK_OEM_AX},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str88, VK_OEM_AX},
 #line 108 "win32_vk.list"
-      {gperf_offsetof(stringpool, 89), VK_BROWSER_BACK},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str89, VK_BROWSER_BACK},
 #line 137 "win32_vk.list"
-      {gperf_offsetof(stringpool, 90), VK_OEM_8},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str90, VK_OEM_8},
 #line 129 "win32_vk.list"
-      {gperf_offsetof(stringpool, 91), VK_OEM_MINUS},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str91, VK_OEM_MINUS},
 #line 162 "win32_vk.list"
-      {gperf_offsetof(stringpool, 92), VK_PLAY},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str92, VK_PLAY},
 #line 131 "win32_vk.list"
-      {gperf_offsetof(stringpool, 93), VK_OEM_2},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str93, VK_OEM_2},
 #line 15 "win32_vk.list"
-      {gperf_offsetof(stringpool, 94), VK_CLEAR},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str94, VK_CLEAR},
 #line 99 "win32_vk.list"
-      {gperf_offsetof(stringpool, 95), VK_OEM_FJ_TOUROKU},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str95, VK_OEM_FJ_TOUROKU},
 #line 147 "win32_vk.list"
-      {gperf_offsetof(stringpool, 96), VK_OEM_PA1},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str96, VK_OEM_PA1},
 #line 140 "win32_vk.list"
-      {gperf_offsetof(stringpool, 97), VK_ICO_HELP},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str97, VK_ICO_HELP},
 #line 112 "win32_vk.list"
-      {gperf_offsetof(stringpool, 98), VK_BROWSER_SEARCH},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str98, VK_BROWSER_SEARCH},
 #line 53 "win32_vk.list"
-      {gperf_offsetof(stringpool, 99), VK_SLEEP},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str99, VK_SLEEP},
       {-1},
 #line 70 "win32_vk.list"
-      {gperf_offsetof(stringpool, 101), VK_F1},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str101, VK_F1},
 #line 148 "win32_vk.list"
-      {gperf_offsetof(stringpool, 102), VK_OEM_PA2},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str102, VK_OEM_PA2},
 #line 154 "win32_vk.list"
-      {gperf_offsetof(stringpool, 103), VK_OEM_COPY},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str103, VK_OEM_COPY},
 #line 77 "win32_vk.list"
-      {gperf_offsetof(stringpool, 104), VK_F8},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str104, VK_F8},
 #line 88 "win32_vk.list"
-      {gperf_offsetof(stringpool, 105), VK_F19},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str105, VK_F19},
 #line 41 "win32_vk.list"
-      {gperf_offsetof(stringpool, 106), VK_RIGHT},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str106, VK_RIGHT},
 #line 71 "win32_vk.list"
-      {gperf_offsetof(stringpool, 107), VK_F2},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str107, VK_F2},
 #line 135 "win32_vk.list"
-      {gperf_offsetof(stringpool, 108), VK_OEM_6},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str108, VK_OEM_6},
 #line 87 "win32_vk.list"
-      {gperf_offsetof(stringpool, 109), VK_F18},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str109, VK_F18},
       {-1},
 #line 117 "win32_vk.list"
-      {gperf_offsetof(stringpool, 111), VK_VOLUME_UP},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str111, VK_VOLUME_UP},
       {-1}, {-1},
 #line 120 "win32_vk.list"
-      {gperf_offsetof(stringpool, 114), VK_MEDIA_STOP},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str114, VK_MEDIA_STOP},
 #line 130 "win32_vk.list"
-      {gperf_offsetof(stringpool, 115), VK_OEM_PERIOD},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str115, VK_OEM_PERIOD},
       {-1},
 #line 161 "win32_vk.list"
-      {gperf_offsetof(stringpool, 117), VK_EREOF},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str117, VK_EREOF},
       {-1}, {-1}, {-1},
 #line 114 "win32_vk.list"
-      {gperf_offsetof(stringpool, 121), VK_BROWSER_HOME},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str121, VK_BROWSER_HOME},
 #line 75 "win32_vk.list"
-      {gperf_offsetof(stringpool, 122), VK_F6},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str122, VK_F6},
       {-1},
 #line 110 "win32_vk.list"
-      {gperf_offsetof(stringpool, 124), VK_BROWSER_REFRESH},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str124, VK_BROWSER_REFRESH},
       {-1},
 #line 165 "win32_vk.list"
-      {gperf_offsetof(stringpool, 126), VK_PA1},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str126, VK_PA1},
 #line 142 "win32_vk.list"
-      {gperf_offsetof(stringpool, 127), VK_PROCESSKEY},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str127, VK_PROCESSKEY},
 #line 68 "win32_vk.list"
-      {gperf_offsetof(stringpool, 128), VK_DECIMAL},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str128, VK_DECIMAL},
 #line 132 "win32_vk.list"
-      {gperf_offsetof(stringpool, 129), VK_OEM_3},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str129, VK_OEM_3},
 #line 107 "win32_vk.list"
-      {gperf_offsetof(stringpool, 130), VK_RMENU},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str130, VK_RMENU},
 #line 106 "win32_vk.list"
-      {gperf_offsetof(stringpool, 131), VK_LMENU},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str131, VK_LMENU},
 #line 98 "win32_vk.list"
-      {gperf_offsetof(stringpool, 132), VK_OEM_FJ_MASSHOU},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str132, VK_OEM_FJ_MASSHOU},
 #line 54 "win32_vk.list"
-      {gperf_offsetof(stringpool, 133), VK_NUMPAD0},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str133, VK_NUMPAD0},
 #line 24 "win32_vk.list"
-      {gperf_offsetof(stringpool, 134), VK_HANGUL},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str134, VK_HANGUL},
 #line 63 "win32_vk.list"
-      {gperf_offsetof(stringpool, 135), VK_NUMPAD9},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str135, VK_NUMPAD9},
 #line 23 "win32_vk.list"
-      {gperf_offsetof(stringpool, 136), VK_HANGEUL},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str136, VK_HANGEUL},
 #line 134 "win32_vk.list"
-      {gperf_offsetof(stringpool, 137), VK_OEM_5},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str137, VK_OEM_5},
 #line 149 "win32_vk.list"
-      {gperf_offsetof(stringpool, 138), VK_OEM_PA3},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str138, VK_OEM_PA3},
 #line 115 "win32_vk.list"
-      {gperf_offsetof(stringpool, 139), VK_VOLUME_MUTE},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str139, VK_VOLUME_MUTE},
 #line 133 "win32_vk.list"
-      {gperf_offsetof(stringpool, 140), VK_OEM_4},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str140, VK_OEM_4},
 #line 122 "win32_vk.list"
-      {gperf_offsetof(stringpool, 141), VK_LAUNCH_MAIL},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str141, VK_LAUNCH_MAIL},
 #line 97 "win32_vk.list"
-      {gperf_offsetof(stringpool, 142), VK_OEM_FJ_JISHO},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str142, VK_OEM_FJ_JISHO},
 #line 72 "win32_vk.list"
-      {gperf_offsetof(stringpool, 143), VK_F3},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str143, VK_F3},
 #line 101 "win32_vk.list"
-      {gperf_offsetof(stringpool, 144), VK_OEM_FJ_ROYA},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str144, VK_OEM_FJ_ROYA},
 #line 100 "win32_vk.list"
-      {gperf_offsetof(stringpool, 145), VK_OEM_FJ_LOYA},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str145, VK_OEM_FJ_LOYA},
       {-1},
 #line 42 "win32_vk.list"
-      {gperf_offsetof(stringpool, 147), VK_DOWN},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str147, VK_DOWN},
       {-1},
 #line 153 "win32_vk.list"
-      {gperf_offsetof(stringpool, 149), VK_OEM_FINISH},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str149, VK_OEM_FINISH},
       {-1},
 #line 74 "win32_vk.list"
-      {gperf_offsetof(stringpool, 151), VK_F5},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str151, VK_F5},
       {-1},
 #line 136 "win32_vk.list"
-      {gperf_offsetof(stringpool, 153), VK_OEM_7},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str153, VK_OEM_7},
 #line 73 "win32_vk.list"
-      {gperf_offsetof(stringpool, 154), VK_F4},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str154, VK_F4},
 #line 86 "win32_vk.list"
-      {gperf_offsetof(stringpool, 155), VK_F17},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str155, VK_F17},
 #line 55 "win32_vk.list"
-      {gperf_offsetof(stringpool, 156), VK_NUMPAD1},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str156, VK_NUMPAD1},
 #line 141 "win32_vk.list"
-      {gperf_offsetof(stringpool, 157), VK_ICO_00},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str157, VK_ICO_00},
       {-1},
 #line 62 "win32_vk.list"
-      {gperf_offsetof(stringpool, 159), VK_NUMPAD8},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str159, VK_NUMPAD8},
       {-1}, {-1},
 #line 56 "win32_vk.list"
-      {gperf_offsetof(stringpool, 162), VK_NUMPAD2},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str162, VK_NUMPAD2},
       {-1},
 #line 124 "win32_vk.list"
-      {gperf_offsetof(stringpool, 164), VK_LAUNCH_APP1},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str164, VK_LAUNCH_APP1},
 #line 109 "win32_vk.list"
-      {gperf_offsetof(stringpool, 165), VK_BROWSER_FORWARD},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str165, VK_BROWSER_FORWARD},
       {-1},
 #line 76 "win32_vk.list"
-      {gperf_offsetof(stringpool, 167), VK_F7},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str167, VK_F7},
       {-1}, {-1},
 #line 125 "win32_vk.list"
-      {gperf_offsetof(stringpool, 170), VK_LAUNCH_APP2},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str170, VK_LAUNCH_APP2},
 #line 64 "win32_vk.list"
-      {gperf_offsetof(stringpool, 171), VK_MULTIPLY},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str171, VK_MULTIPLY},
       {-1}, {-1},
 #line 45 "win32_vk.list"
-      {gperf_offsetof(stringpool, 174), VK_EXECUTE},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str174, VK_EXECUTE},
       {-1},
 #line 113 "win32_vk.list"
-      {gperf_offsetof(stringpool, 176), VK_BROWSER_FAVORITES},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str176, VK_BROWSER_FAVORITES},
 #line 60 "win32_vk.list"
-      {gperf_offsetof(stringpool, 177), VK_NUMPAD6},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str177, VK_NUMPAD6},
       {-1},
 #line 85 "win32_vk.list"
-      {gperf_offsetof(stringpool, 179), VK_F16},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str179, VK_F16},
       {-1}, {-1},
 #line 79 "win32_vk.list"
-      {gperf_offsetof(stringpool, 182), VK_F10},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str182, VK_F10},
       {-1}, {-1},
 #line 116 "win32_vk.list"
-      {gperf_offsetof(stringpool, 185), VK_VOLUME_DOWN},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str185, VK_VOLUME_DOWN},
       {-1}, {-1},
 #line 89 "win32_vk.list"
-      {gperf_offsetof(stringpool, 188), VK_F20},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str188, VK_F20},
 #line 119 "win32_vk.list"
-      {gperf_offsetof(stringpool, 189), VK_MEDIA_PREV_TRACK},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str189, VK_MEDIA_PREV_TRACK},
       {-1},
 #line 33 "win32_vk.list"
-      {gperf_offsetof(stringpool, 191), VK_MODECHANGE},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str191, VK_MODECHANGE},
       {-1}, {-1}, {-1}, {-1}, {-1},
 #line 83 "win32_vk.list"
-      {gperf_offsetof(stringpool, 197), VK_F14},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str197, VK_F14},
 #line 57 "win32_vk.list"
-      {gperf_offsetof(stringpool, 198), VK_NUMPAD3},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str198, VK_NUMPAD3},
 #line 11 "win32_vk.list"
-      {gperf_offsetof(stringpool, 199), VK_XBUTTON1},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str199, VK_XBUTTON1},
       {-1}, {-1}, {-1},
 #line 93 "win32_vk.list"
-      {gperf_offsetof(stringpool, 203), VK_F24},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str203, VK_F24},
       {-1},
 #line 12 "win32_vk.list"
-      {gperf_offsetof(stringpool, 205), VK_XBUTTON2},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str205, VK_XBUTTON2},
 #line 59 "win32_vk.list"
-      {gperf_offsetof(stringpool, 206), VK_NUMPAD5},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str206, VK_NUMPAD5},
       {-1}, {-1},
 #line 58 "win32_vk.list"
-      {gperf_offsetof(stringpool, 209), VK_NUMPAD4},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str209, VK_NUMPAD4},
       {-1}, {-1}, {-1}, {-1}, {-1},
 #line 121 "win32_vk.list"
-      {gperf_offsetof(stringpool, 215), VK_MEDIA_PLAY_PAUSE},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str215, VK_MEDIA_PLAY_PAUSE},
       {-1},
 #line 123 "win32_vk.list"
-      {gperf_offsetof(stringpool, 217), VK_LAUNCH_MEDIA_SELECT},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str217, VK_LAUNCH_MEDIA_SELECT},
 #line 80 "win32_vk.list"
-      {gperf_offsetof(stringpool, 218), VK_F11},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str218, VK_F11},
       {-1},
 #line 139 "win32_vk.list"
-      {gperf_offsetof(stringpool, 220), VK_OEM_102},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str220, VK_OEM_102},
 #line 118 "win32_vk.list"
-      {gperf_offsetof(stringpool, 221), VK_MEDIA_NEXT_TRACK},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str221, VK_MEDIA_NEXT_TRACK},
 #line 61 "win32_vk.list"
-      {gperf_offsetof(stringpool, 222), VK_NUMPAD7},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str222, VK_NUMPAD7},
       {-1},
 #line 90 "win32_vk.list"
-      {gperf_offsetof(stringpool, 224), VK_F21},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str224, VK_F21},
       {-1},
 #line 82 "win32_vk.list"
-      {gperf_offsetof(stringpool, 226), VK_F13},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str226, VK_F13},
       {-1}, {-1},
 #line 81 "win32_vk.list"
-      {gperf_offsetof(stringpool, 229), VK_F12},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str229, VK_F12},
       {-1}, {-1},
 #line 92 "win32_vk.list"
-      {gperf_offsetof(stringpool, 232), VK_F23},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str232, VK_F23},
       {-1}, {-1},
 #line 91 "win32_vk.list"
-      {gperf_offsetof(stringpool, 235), VK_F22},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str235, VK_F22},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
 #line 84 "win32_vk.list"
-      {gperf_offsetof(stringpool, 242), VK_F15},
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str242, VK_F15},
       {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1}, {-1},
       {-1}, {-1}, {-1}, {-1},
 #line 69 "win32_vk.list"
-      {gperf_offsetof(stringpool, 256), VK_DIVIDE}
+      {(int)(size_t)&((struct stringpool_t *)0)->stringpool_str256, VK_DIVIDE}
     };
 
   if (len <= MAX_WORD_LENGTH && len >= MIN_WORD_LENGTH)
diff --git a/ext/io/console/win32_vk.list b/ext/io/console/win32_vk.list
index 7909a4d1f0..5df3d6da57 100644
--- a/ext/io/console/win32_vk.list
+++ b/ext/io/console/win32_vk.list
@@ -1,6 +1,6 @@
 %{
 struct vktable {short ofs; unsigned short vk;};
-static const struct vktable *console_win32_vk(/*!ANSI{*/const char *, unsigned int/*}!ANSI*/);
+static const struct vktable *console_win32_vk(const char *, size_t);
 %}
 struct vktable
 %%
diff --git a/ext/io/nonblock/io-nonblock.gemspec b/ext/io/nonblock/io-nonblock.gemspec
index 34d736650b..d6df21a84d 100644
--- a/ext/io/nonblock/io-nonblock.gemspec
+++ b/ext/io/nonblock/io-nonblock.gemspec
@@ -1,6 +1,6 @@
 Gem::Specification.new do |spec|
   spec.name          = "io-nonblock"
-  spec.version       = "0.1.0"
+  spec.version       = "0.2.0"
   spec.authors       = ["Nobu Nakada"]
   spec.email         = ["nobu@ruby-lang.org"]
 
@@ -13,13 +13,13 @@ Gem::Specification.new do |spec|
   spec.metadata["homepage_uri"] = spec.homepage
   spec.metadata["source_code_uri"] = spec.homepage
 
-  spec.files         = Dir.chdir(File.expand_path('..', __FILE__)) do
-    %x[git ls-files -z].split("\x0").reject do |f|
-      f.match(%r{\A(?:test|spec|features)/|\A\.(?:git|travis)})
-    end
-  end
+  spec.files         = %w[
+    COPYING
+    README.md
+    ext/io/nonblock/depend
+    ext/io/nonblock/extconf.rb
+    ext/io/nonblock/nonblock.c
+  ]
   spec.extensions    = %w[ext/io/nonblock/extconf.rb]
-  spec.bindir        = "exe"
-  spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
   spec.require_paths = ["lib"]
 end
diff --git a/ext/io/nonblock/nonblock.c b/ext/io/nonblock/nonblock.c
index 1c0bdc68e7..b8a40ff38e 100644
--- a/ext/io/nonblock/nonblock.c
+++ b/ext/io/nonblock/nonblock.c
@@ -19,14 +19,14 @@
 
 #ifdef F_GETFL
 static int
-io_nonblock_mode(int fd)
+get_fcntl_flags(int fd)
 {
     int f = fcntl(fd, F_GETFL);
     if (f == -1) rb_sys_fail(0);
     return f;
 }
 #else
-#define io_nonblock_mode(fd) ((void)(fd), 0)
+#define get_fcntl_flags(fd) ((void)(fd), 0)
 #endif
 
 #ifdef F_GETFL
@@ -41,7 +41,7 @@ rb_io_nonblock_p(VALUE io)
 {
     rb_io_t *fptr;
     GetOpenFile(io, fptr);
-    if (io_nonblock_mode(fptr->fd) & O_NONBLOCK)
+    if (get_fcntl_flags(fptr->fd) & O_NONBLOCK)
 	return Qtrue;
     return Qfalse;
 }
@@ -50,6 +50,13 @@ rb_io_nonblock_p(VALUE io)
 #endif
 
 #ifdef F_SETFL
+static void
+set_fcntl_flags(int fd, int f)
+{
+    if (fcntl(fd, F_SETFL, f) == -1)
+	rb_sys_fail(0);
+}
+
 static int
 io_nonblock_set(int fd, int f, int nb)
 {
@@ -63,8 +70,7 @@ io_nonblock_set(int fd, int f, int nb)
 	    return 0;
 	f &= ~O_NONBLOCK;
     }
-    if (fcntl(fd, F_SETFL, f) == -1)
-	rb_sys_fail(0);
+    set_fcntl_flags(fd, f);
     return 1;
 }
 
@@ -74,6 +80,46 @@ io_nonblock_set(int fd, int f, int nb)
  *
  * Enables non-blocking mode on a stream when set to
  * +true+, and blocking mode when set to +false+.
+ *
+ * This method set or clear O_NONBLOCK flag for the file descriptor
+ * in <em>ios</em>.
+ *
+ * The behavior of most IO methods is not affected by this flag
+ * because they retry system calls to complete their task
+ * after EAGAIN and partial read/write.
+ * (An exception is IO#syswrite which doesn't retry.)
+ *
+ * This method can be used to clear non-blocking mode of standard I/O.
+ * Since nonblocking methods (read_nonblock, etc.) set non-blocking mode but
+ * they doesn't clear it, this method is usable as follows.
+ *
+ *   END { STDOUT.nonblock = false }
+ *   STDOUT.write_nonblock("foo")
+ *
+ * Since the flag is shared across processes and
+ * many non-Ruby commands doesn't expect standard I/O with non-blocking mode,
+ * it would be safe to clear the flag before Ruby program exits.
+ *
+ * For example following Ruby program leaves STDIN/STDOUT/STDER non-blocking mode.
+ * (STDIN, STDOUT and STDERR are connected to a terminal.
+ * So making one of them nonblocking-mode effects other two.)
+ * Thus cat command try to read from standard input and
+ * it causes "Resource temporarily unavailable" error (EAGAIN).
+ *
+ *   % ruby -e '
+ *   STDOUT.write_nonblock("foo\n")'; cat
+ *   foo
+ *   cat: -: Resource temporarily unavailable
+ *
+ * Clearing the flag makes the behavior of cat command normal.
+ * (cat command waits input from standard input.)
+ *
+ *   % ruby -rio/nonblock -e '
+ *   END { STDOUT.nonblock = false }
+ *   STDOUT.write_nonblock("foo")
+ *   '; cat
+ *   foo
+ *
  */
 static VALUE
 rb_io_nonblock_set(VALUE io, VALUE nb)
@@ -83,7 +129,7 @@ rb_io_nonblock_set(VALUE io, VALUE nb)
     if (RTEST(nb))
 	rb_io_set_nonblock(fptr);
     else
-	io_nonblock_set(fptr->fd, io_nonblock_mode(fptr->fd), RTEST(nb));
+	io_nonblock_set(fptr->fd, get_fcntl_flags(fptr->fd), RTEST(nb));
     return io;
 }
 
@@ -91,15 +137,14 @@ static VALUE
 io_nonblock_restore(VALUE arg)
 {
     int *restore = (int *)arg;
-    if (fcntl(restore[0], F_SETFL, restore[1]) == -1)
-	rb_sys_fail(0);
+    set_fcntl_flags(restore[0], restore[1]);
     return Qnil;
 }
 
 /*
  * call-seq:
- *   io.nonblock {|io| } -> io
- *   io.nonblock(boolean) {|io| } -> io
+ *   io.nonblock {|io| } -> object
+ *   io.nonblock(boolean) {|io| } -> object
  *
  * Yields +self+ in non-blocking mode.
  *
@@ -119,7 +164,7 @@ rb_io_nonblock_block(int argc, VALUE *argv, VALUE io)
 	rb_scan_args(argc, argv, "01", &v);
 	nb = RTEST(v);
     }
-    f = io_nonblock_mode(fptr->fd);
+    f = get_fcntl_flags(fptr->fd);
     restore[0] = fptr->fd;
     restore[1] = f;
     if (!io_nonblock_set(fptr->fd, f, nb))
diff --git a/ext/io/wait/extconf.rb b/ext/io/wait/extconf.rb
index eecdcce99f..c6230b7783 100644
--- a/ext/io/wait/extconf.rb
+++ b/ext/io/wait/extconf.rb
@@ -5,7 +5,7 @@ if RUBY_VERSION < "2.6"
   File.write("Makefile", dummy_makefile($srcdir).join(""))
 else
   target = "io/wait"
-  have_func("rb_io_wait")
+  have_func("rb_io_wait", "ruby/io.h")
   unless macro_defined?("DOSISH", "#include <ruby.h>")
     have_header(ioctl_h = "sys/ioctl.h") or ioctl_h = nil
     fionread = %w[sys/ioctl.h sys/filio.h sys/socket.h].find do |h|
diff --git a/ext/io/wait/io-wait.gemspec b/ext/io/wait/io-wait.gemspec
index ad1624585b..ebc1f6f5c7 100644
--- a/ext/io/wait/io-wait.gemspec
+++ b/ext/io/wait/io-wait.gemspec
@@ -1,10 +1,10 @@
-_VERSION = "0.2.2.pre1"
+_VERSION = "0.3.0"
 
 Gem::Specification.new do |spec|
   spec.name          = "io-wait"
   spec.version       = _VERSION
-  spec.authors       = ["Nobu Nakada"]
-  spec.email         = ["nobu@ruby-lang.org"]
+  spec.authors       = ["Nobu Nakada", "Charles Oliver Nutter"]
+  spec.email         = ["nobu@ruby-lang.org", "headius@headius.com"]
 
   spec.summary       = %q{Waits until IO is readable or writable without blocking.}
   spec.description   = %q{Waits until IO is readable or writable without blocking.}
@@ -16,11 +16,23 @@ Gem::Specification.new do |spec|
 
   spec.files         = Dir.chdir(File.expand_path('..', __FILE__)) do
     `git ls-files -z`.split("\x0").reject do |f|
-      (f == __FILE__) || f.match(%r{\A(?:(?:bin|test|spec|features|rakelib)/|\.(?:git|travis|circleci)|appveyor|Rakefile)})
+      File.identical?(f, __FILE__) || f.match(%r{\A(?:(?:bin|test|spec|features|rakelib)/|\.(?:git|travis|circleci)|appveyor|Rakefile)})
     end
   end
-  spec.extensions    = %w[ext/io/wait/extconf.rb]
   spec.bindir        = "exe"
   spec.executables   = []
   spec.require_paths = ["lib"]
+
+  jruby = true if Gem::Platform.new('java') =~ spec.platform or RUBY_ENGINE == 'jruby'
+  spec.files.delete_if do |f|
+    f.end_with?(".java") or
+      f.start_with?("ext/") && (jruby ^ f.start_with?("ext/java/"))
+  end
+  if jruby
+    spec.platform = 'java'
+    spec.files << "lib/io/wait.jar"
+    spec.require_paths += ["ext/java/lib"]
+  else
+    spec.extensions    = %w[ext/io/wait/extconf.rb]
+  end
 end
diff --git a/ext/io/wait/wait.c b/ext/io/wait/wait.c
index 568c7b54a8..d74afb580b 100644
--- a/ext/io/wait/wait.c
+++ b/ext/io/wait/wait.c
@@ -41,22 +41,17 @@
 #endif
 
 #ifndef HAVE_RB_IO_WAIT
-static VALUE io_ready_p _((VALUE io));
-static VALUE io_wait_readable _((int argc, VALUE *argv, VALUE io));
-static VALUE io_wait_writable _((int argc, VALUE *argv, VALUE io));
-void Init_wait _((void));
-
 static struct timeval *
 get_timeout(int argc, VALUE *argv, struct timeval *timerec)
 {
     VALUE timeout = Qnil;
     rb_check_arity(argc, 0, 1);
     if (!argc || NIL_P(timeout = argv[0])) {
-	return NULL;
+        return NULL;
     }
     else {
-	*timerec = rb_time_interval(timeout);
-	return timerec;
+        *timerec = rb_time_interval(timeout);
+        return timerec;
     }
 }
 
@@ -65,7 +60,7 @@ wait_for_single_fd(rb_io_t *fptr, int events, struct timeval *tv)
 {
     int i = rb_wait_for_single_fd(fptr->fd, events, tv);
     if (i < 0)
-	rb_sys_fail(0);
+        rb_sys_fail(0);
     rb_io_check_closed(fptr);
     return (i & events);
 }
@@ -100,21 +95,24 @@ io_nread(VALUE io)
 
 #ifdef HAVE_RB_IO_WAIT
 static VALUE
-io_wait_event(VALUE io, int event, VALUE timeout)
+io_wait_event(VALUE io, int event, VALUE timeout, int return_io)
 {
     VALUE result = rb_io_wait(io, RB_INT2NUM(event), timeout);
 
     if (!RB_TEST(result)) {
-	return Qnil;
+        return Qnil;
     }
 
     int mask = RB_NUM2INT(result);
 
     if (mask & event) {
-	return io;
+        if (return_io)
+            return io;
+        else
+            return result;
     }
     else {
-	return Qfalse;
+        return Qfalse;
     }
 }
 #endif
@@ -142,15 +140,15 @@ io_ready_p(VALUE io)
     if (rb_io_read_pending(fptr)) return Qtrue;
 
 #ifndef HAVE_RB_IO_WAIT
-    if (wait_for_single_fd(fptr, RB_WAITFD_IN, &tv))
-	return Qtrue;
+    return wait_for_single_fd(fptr, RB_WAITFD_IN, &tv) ? Qtrue : Qfalse;
 #else
-    if (RTEST(io_wait_event(io, RUBY_IO_READABLE, RB_INT2NUM(0))))
-	return Qtrue;
+    return io_wait_event(io, RUBY_IO_READABLE, RB_INT2NUM(0), 1);
 #endif
-    return Qfalse;
 }
 
+/* Ruby 3.2+ can define these methods. This macro indicates that case. */
+#ifndef RUBY_IO_WAIT_METHODS
+
 /*
  * call-seq:
  *   io.wait_readable          -> truthy or falsy
@@ -182,14 +180,14 @@ io_wait_readable(int argc, VALUE *argv, VALUE io)
 
 #ifndef HAVE_RB_IO_WAIT
     if (wait_for_single_fd(fptr, RB_WAITFD_IN, tv)) {
-	return io;
+        return io;
     }
     return Qnil;
 #else
     rb_check_arity(argc, 0, 1);
     VALUE timeout = (argc == 1 ? argv[0] : Qnil);
 
-    return io_wait_event(io, RUBY_IO_READABLE, timeout);
+    return io_wait_event(io, RUBY_IO_READABLE, timeout, 1);
 #endif
 }
 
@@ -218,14 +216,14 @@ io_wait_writable(int argc, VALUE *argv, VALUE io)
 #ifndef HAVE_RB_IO_WAIT
     tv = get_timeout(argc, argv, &timerec);
     if (wait_for_single_fd(fptr, RB_WAITFD_OUT, tv)) {
-	return io;
+        return io;
     }
     return Qnil;
 #else
     rb_check_arity(argc, 0, 1);
     VALUE timeout = (argc == 1 ? argv[0] : Qnil);
 
-    return io_wait_event(io, RUBY_IO_WRITABLE, timeout);
+    return io_wait_event(io, RUBY_IO_WRITABLE, timeout, 1);
 #endif
 }
 
@@ -236,7 +234,8 @@ io_wait_writable(int argc, VALUE *argv, VALUE io)
  *   io.wait_priority(timeout) -> truthy or falsy
  *
  * Waits until IO is priority and returns a truthy value or a falsy
- * value when times out.
+ * value when times out. Priority data is sent and received using
+ * the Socket::MSG_OOB flag and is typically limited to streams.
  *
  * You must require 'io/wait' to use this method.
  */
@@ -253,7 +252,7 @@ io_wait_priority(int argc, VALUE *argv, VALUE io)
     rb_check_arity(argc, 0, 1);
     VALUE timeout = argc == 1 ? argv[0] : Qnil;
 
-    return io_wait_event(io, RUBY_IO_PRIORITY, timeout);
+    return io_wait_event(io, RUBY_IO_PRIORITY, timeout, 1);
 }
 #endif
 
@@ -261,40 +260,52 @@ static int
 wait_mode_sym(VALUE mode)
 {
     if (mode == ID2SYM(rb_intern("r"))) {
-	return RB_WAITFD_IN;
+        return RB_WAITFD_IN;
     }
     if (mode == ID2SYM(rb_intern("read"))) {
-	return RB_WAITFD_IN;
+        return RB_WAITFD_IN;
     }
     if (mode == ID2SYM(rb_intern("readable"))) {
-	return RB_WAITFD_IN;
+        return RB_WAITFD_IN;
     }
     if (mode == ID2SYM(rb_intern("w"))) {
-	return RB_WAITFD_OUT;
+        return RB_WAITFD_OUT;
     }
     if (mode == ID2SYM(rb_intern("write"))) {
-	return RB_WAITFD_OUT;
+        return RB_WAITFD_OUT;
     }
     if (mode == ID2SYM(rb_intern("writable"))) {
-	return RB_WAITFD_OUT;
+        return RB_WAITFD_OUT;
     }
     if (mode == ID2SYM(rb_intern("rw"))) {
-	return RB_WAITFD_IN|RB_WAITFD_OUT;
+        return RB_WAITFD_IN|RB_WAITFD_OUT;
     }
     if (mode == ID2SYM(rb_intern("read_write"))) {
-	return RB_WAITFD_IN|RB_WAITFD_OUT;
+        return RB_WAITFD_IN|RB_WAITFD_OUT;
     }
     if (mode == ID2SYM(rb_intern("readable_writable"))) {
-	return RB_WAITFD_IN|RB_WAITFD_OUT;
+        return RB_WAITFD_IN|RB_WAITFD_OUT;
     }
     rb_raise(rb_eArgError, "unsupported mode: %"PRIsVALUE, mode);
     return 0;
 }
 
+#ifdef HAVE_RB_IO_WAIT
+static inline rb_io_event_t
+io_event_from_value(VALUE value)
+{
+    int events = RB_NUM2INT(value);
+
+    if (events <= 0) rb_raise(rb_eArgError, "Events must be positive integer!");
+
+    return events;
+}
+#endif
+
 /*
  * call-seq:
- *   io.wait(events, timeout) -> truthy or falsy
- *   io.wait(timeout = nil, mode = :read) -> truthy or falsy.
+ *   io.wait(events, timeout) -> event mask, false or nil
+ *   io.wait(timeout = nil, mode = :read) -> self, true, or false
  *
  * Waits until the IO becomes ready for the specified events and returns the
  * subset of events that become ready, or a falsy value when times out.
@@ -322,61 +333,77 @@ io_wait(int argc, VALUE *argv, VALUE io)
 
     GetOpenFile(io, fptr);
     for (i = 0; i < argc; ++i) {
-	if (SYMBOL_P(argv[i])) {
-	    event |= wait_mode_sym(argv[i]);
-	}
-	else {
-	    *(tv = &timerec) = rb_time_interval(argv[i]);
-	}
+        if (SYMBOL_P(argv[i])) {
+            event |= wait_mode_sym(argv[i]);
+        }
+        else {
+            *(tv = &timerec) = rb_time_interval(argv[i]);
+        }
     }
     /* rb_time_interval() and might_mode() might convert the argument */
     rb_io_check_closed(fptr);
     if (!event) event = RB_WAITFD_IN;
     if ((event & RB_WAITFD_IN) && rb_io_read_pending(fptr))
-	return Qtrue;
+        return Qtrue;
     if (wait_for_single_fd(fptr, event, tv))
-	return io;
+        return io;
     return Qnil;
 #else
     VALUE timeout = Qundef;
     rb_io_event_t events = 0;
+    int i, return_io = 0;
 
+    /* The documented signature for this method is actually incorrect.
+     * A single timeout is allowed in any position, and multiple symbols can be given.
+     * Whether this is intentional or not, I don't know, and as such I consider this to
+     * be a legacy/slow path. */
     if (argc != 2 || (RB_SYMBOL_P(argv[0]) || RB_SYMBOL_P(argv[1]))) {
-	for (int i = 0; i < argc; i += 1) {
-	    if (RB_SYMBOL_P(argv[i])) {
-		events |= wait_mode_sym(argv[i]);
-	    }
-	    else if (timeout == Qundef) {
-		rb_time_interval(timeout = argv[i]);
-	    }
-	    else {
-		rb_raise(rb_eArgError, "timeout given more than once");
-	    }
-	}
-	if (timeout == Qundef) timeout = Qnil;
+        /* We'd prefer to return the actual mask, but this form would return the io itself: */
+        return_io = 1;
+
+        /* Slow/messy path: */
+        for (i = 0; i < argc; i += 1) {
+            if (RB_SYMBOL_P(argv[i])) {
+                events |= wait_mode_sym(argv[i]);
+            }
+            else if (timeout == Qundef) {
+                rb_time_interval(timeout = argv[i]);
+            }
+            else {
+                rb_raise(rb_eArgError, "timeout given more than once");
+            }
+        }
+
+        if (timeout == Qundef) timeout = Qnil;
+
+        if (events == 0) {
+            events = RUBY_IO_READABLE;
+        }
     }
-    else /* argc == 2 */ {
-	events = RB_NUM2UINT(argv[0]);
-	timeout = argv[1];
-    }
-
-    if (events == 0) {
-	events = RUBY_IO_READABLE;
+    else /* argc == 2 and neither are symbols */ {
+        /* This is the fast path: */
+        events = io_event_from_value(argv[0]);
+        timeout = argv[1];
     }
 
     if (events & RUBY_IO_READABLE) {
-	rb_io_t *fptr = NULL;
-	RB_IO_POINTER(io, fptr);
-
-	if (rb_io_read_pending(fptr)) {
-	    return Qtrue;
-	}
+        rb_io_t *fptr = NULL;
+        RB_IO_POINTER(io, fptr);
+
+        if (rb_io_read_pending(fptr)) {
+            /* This was the original behaviour: */
+            if (return_io) return Qtrue;
+            /* New behaviour always returns an event mask: */
+            else return RB_INT2NUM(RUBY_IO_READABLE);
+        }
     }
 
-    return io_wait_event(io, events, timeout);
+    return io_wait_event(io, events, timeout, return_io);
 #endif
 }
 
+#endif /* RUBY_IO_WAIT_METHODS */
+
 /*
  * IO wait methods
  */
@@ -391,6 +418,7 @@ Init_wait(void)
     rb_define_method(rb_cIO, "nread", io_nread, 0);
     rb_define_method(rb_cIO, "ready?", io_ready_p, 0);
 
+#ifndef RUBY_IO_WAIT_METHODS
     rb_define_method(rb_cIO, "wait", io_wait, -1);
 
     rb_define_method(rb_cIO, "wait_readable", io_wait_readable, -1);
@@ -398,4 +426,5 @@ Init_wait(void)
 #ifdef HAVE_RB_IO_WAIT
     rb_define_method(rb_cIO, "wait_priority", io_wait_priority, -1);
 #endif
+#endif
 }
diff --git a/ext/json/VERSION b/ext/json/VERSION
index 6a6a3d8e35..ec1cf33c3f 100644
--- a/ext/json/VERSION
+++ b/ext/json/VERSION
@@ -1 +1 @@
-2.6.1
+2.6.3
diff --git a/ext/json/generator/generator.c b/ext/json/generator/generator.c
index e3a83472e1..98d0ea46c3 100644
--- a/ext/json/generator/generator.c
+++ b/ext/json/generator/generator.c
@@ -997,10 +997,10 @@ static void generate_json_float(FBuffer *buffer, VALUE Vstate, JSON_Generator_St
     if (!allow_nan) {
         if (isinf(value)) {
             fbuffer_free(buffer);
-            rb_raise(eGeneratorError, "%u: %"PRIsVALUE" not allowed in JSON", __LINE__, RB_OBJ_STRING(tmp));
+            rb_raise(eGeneratorError, "%"PRIsVALUE" not allowed in JSON", RB_OBJ_STRING(tmp));
         } else if (isnan(value)) {
             fbuffer_free(buffer);
-            rb_raise(eGeneratorError, "%u: %"PRIsVALUE" not allowed in JSON", __LINE__, RB_OBJ_STRING(tmp));
+            rb_raise(eGeneratorError, "%"PRIsVALUE" not allowed in JSON", RB_OBJ_STRING(tmp));
         }
     }
     fbuffer_append_str(buffer, tmp);
diff --git a/ext/json/lib/json/version.rb b/ext/json/lib/json/version.rb
index 35e8dd3252..3d4326d836 100644
--- a/ext/json/lib/json/version.rb
+++ b/ext/json/lib/json/version.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: false
 module JSON
   # JSON version
-  VERSION         = '2.6.1'
+  VERSION         = '2.6.3'
   VERSION_ARRAY   = VERSION.split(/\./).map { |x| x.to_i } # :nodoc:
   VERSION_MAJOR   = VERSION_ARRAY[0] # :nodoc:
   VERSION_MINOR   = VERSION_ARRAY[1] # :nodoc:
diff --git a/ext/json/parser/extconf.rb b/ext/json/parser/extconf.rb
index feb586e1b4..4723a02aee 100644
--- a/ext/json/parser/extconf.rb
+++ b/ext/json/parser/extconf.rb
@@ -1,8 +1,8 @@
 # frozen_string_literal: false
 require 'mkmf'
 
-have_func("rb_enc_raise", "ruby.h")
-have_func("rb_enc_interned_str", "ruby.h")
+have_func("rb_enc_raise", "ruby/encoding.h")
+have_func("rb_enc_interned_str", "ruby/encoding.h")
 
 # checking if String#-@ (str_uminus) dedupes... '
 begin
diff --git a/ext/json/parser/parser.c b/ext/json/parser/parser.c
index b1dc8810c3..9bd7f1971e 100644
--- a/ext/json/parser/parser.c
+++ b/ext/json/parser/parser.c
@@ -948,7 +948,7 @@ static char *JSON_parse_value(JSON_Parser *json, char *p, char *pe, VALUE *resul
 
 					{p = p - 1; } {p+= 1; cs = 29; goto _out;}
 				} else {
-					rb_enc_raise(EXC_ENCODING eParserError, "%u: unexpected token at '%s'", __LINE__, p);
+					rb_enc_raise(EXC_ENCODING eParserError, "unexpected token at '%s'", p);
 				}
 			}
 			np = JSON_parse_float(json, p, pe, result);
@@ -990,7 +990,7 @@ static char *JSON_parse_value(JSON_Parser *json, char *p, char *pe, VALUE *resul
 			if (json->allow_nan) {
 				*result = CInfinity;
 			} else {
-				rb_enc_raise(EXC_ENCODING eParserError, "%u: unexpected token at '%s'", __LINE__, p - 8);
+				rb_enc_raise(EXC_ENCODING eParserError, "unexpected token at '%s'", p - 8);
 			}
 		}
 
@@ -1002,7 +1002,7 @@ static char *JSON_parse_value(JSON_Parser *json, char *p, char *pe, VALUE *resul
 			if (json->allow_nan) {
 				*result = CNaN;
 			} else {
-				rb_enc_raise(EXC_ENCODING eParserError, "%u: unexpected token at '%s'", __LINE__, p - 2);
+				rb_enc_raise(EXC_ENCODING eParserError, "unexpected token at '%s'", p - 2);
 			}
 		}
 
@@ -2348,7 +2348,7 @@ static char *JSON_parse_array(JSON_Parser *json, char *p, char *pe, VALUE *resul
 	if(cs >= JSON_array_first_final) {
 		return p + 1;
 	} else {
-		rb_enc_raise(EXC_ENCODING eParserError, "%u: unexpected token at '%s'", __LINE__, p);
+		rb_enc_raise(EXC_ENCODING eParserError, "unexpected token at '%s'", p);
 		return NULL;
 	}
 }
@@ -2363,9 +2363,17 @@ static VALUE json_string_unescape(char *string, char *stringEnd, int intern, int
 	char buf[4];
 
 	if (bufferSize > MAX_STACK_BUFFER_SIZE) {
+# ifdef HAVE_RB_ENC_INTERNED_STR
+		bufferStart = buffer = ALLOC_N(char, bufferSize ? bufferSize : 1);
+# else
 		bufferStart = buffer = ALLOC_N(char, bufferSize);
+# endif
 	} else {
+# ifdef HAVE_RB_ENC_INTERNED_STR
+		bufferStart = buffer = ALLOCA_N(char, bufferSize ? bufferSize : 1);
+# else
 		bufferStart = buffer = ALLOCA_N(char, bufferSize);
+# endif
 	}
 
 	while (pe < stringEnd) {
@@ -2405,7 +2413,7 @@ static VALUE json_string_unescape(char *string, char *stringEnd, int intern, int
 					}
 					rb_enc_raise(
 					EXC_ENCODING eParserError,
-					"%u: incomplete unicode character escape sequence at '%s'", __LINE__, p
+					"incomplete unicode character escape sequence at '%s'", p
 					);
 				} else {
 					UTF32 ch = unescape_unicode((unsigned char *) ++pe);
@@ -2418,7 +2426,7 @@ static VALUE json_string_unescape(char *string, char *stringEnd, int intern, int
 							}
 							rb_enc_raise(
 							EXC_ENCODING eParserError,
-							"%u: incomplete surrogate pair at '%s'", __LINE__, p
+							"incomplete surrogate pair at '%s'", p
 							);
 						}
 						if (pe[0] == '\\' && pe[1] == 'u') {
@@ -2950,6 +2958,7 @@ static const char MAYBE_UNUSED(_JSON_nfa_pop_trans)[] = {
 *
 *  Parses the current JSON text _source_ and returns the complete data
 *  structure as a result.
+*  It raises JSON::ParseError if fail to parse.
 */
 static VALUE cParser_parse(VALUE self)
 {
@@ -3216,7 +3225,7 @@ static VALUE cParser_parse(VALUE self)
 	if (cs >= JSON_first_final && p == pe) {
 		return result;
 	} else {
-		rb_enc_raise(EXC_ENCODING eParserError, "%u: unexpected token at '%s'", __LINE__, p);
+		rb_enc_raise(EXC_ENCODING eParserError, "unexpected token at '%s'", p);
 		return Qnil;
 	}
 }
diff --git a/ext/json/parser/parser.rl b/ext/json/parser/parser.rl
index f7be1a5acc..2dbdc7ef24 100644
--- a/ext/json/parser/parser.rl
+++ b/ext/json/parser/parser.rl
@@ -222,14 +222,14 @@ static char *JSON_parse_object(JSON_Parser *json, char *p, char *pe, VALUE *resu
         if (json->allow_nan) {
             *result = CNaN;
         } else {
-            rb_enc_raise(EXC_ENCODING eParserError, "%u: unexpected token at '%s'", __LINE__, p - 2);
+            rb_enc_raise(EXC_ENCODING eParserError, "unexpected token at '%s'", p - 2);
         }
     }
     action parse_infinity {
         if (json->allow_nan) {
             *result = CInfinity;
         } else {
-            rb_enc_raise(EXC_ENCODING eParserError, "%u: unexpected token at '%s'", __LINE__, p - 8);
+            rb_enc_raise(EXC_ENCODING eParserError, "unexpected token at '%s'", p - 8);
         }
     }
     action parse_string {
@@ -245,7 +245,7 @@ static char *JSON_parse_object(JSON_Parser *json, char *p, char *pe, VALUE *resu
                 fexec p + 10;
                 fhold; fbreak;
             } else {
-                rb_enc_raise(EXC_ENCODING eParserError, "%u: unexpected token at '%s'", __LINE__, p);
+                rb_enc_raise(EXC_ENCODING eParserError, "unexpected token at '%s'", p);
             }
         }
         np = JSON_parse_float(json, fpc, pe, result);
@@ -447,7 +447,7 @@ static char *JSON_parse_array(JSON_Parser *json, char *p, char *pe, VALUE *resul
     if(cs >= JSON_array_first_final) {
         return p + 1;
     } else {
-        rb_enc_raise(EXC_ENCODING eParserError, "%u: unexpected token at '%s'", __LINE__, p);
+        rb_enc_raise(EXC_ENCODING eParserError, "unexpected token at '%s'", p);
         return NULL;
     }
 }
@@ -462,9 +462,17 @@ static VALUE json_string_unescape(char *string, char *stringEnd, int intern, int
     char buf[4];
 
     if (bufferSize > MAX_STACK_BUFFER_SIZE) {
+# ifdef HAVE_RB_ENC_INTERNED_STR
+      bufferStart = buffer = ALLOC_N(char, bufferSize ? bufferSize : 1);
+# else
       bufferStart = buffer = ALLOC_N(char, bufferSize);
+# endif
     } else {
+# ifdef HAVE_RB_ENC_INTERNED_STR
+      bufferStart = buffer = ALLOCA_N(char, bufferSize ? bufferSize : 1);
+# else
       bufferStart = buffer = ALLOCA_N(char, bufferSize);
+# endif
     }
 
     while (pe < stringEnd) {
@@ -504,7 +512,7 @@ static VALUE json_string_unescape(char *string, char *stringEnd, int intern, int
                       }
                       rb_enc_raise(
                         EXC_ENCODING eParserError,
-                        "%u: incomplete unicode character escape sequence at '%s'", __LINE__, p
+                        "incomplete unicode character escape sequence at '%s'", p
                       );
                     } else {
                         UTF32 ch = unescape_unicode((unsigned char *) ++pe);
@@ -517,7 +525,7 @@ static VALUE json_string_unescape(char *string, char *stringEnd, int intern, int
                               }
                               rb_enc_raise(
                                 EXC_ENCODING eParserError,
-                                "%u: incomplete surrogate pair at '%s'", __LINE__, p
+                                "incomplete surrogate pair at '%s'", p
                                 );
                             }
                             if (pe[0] == '\\' && pe[1] == 'u') {
@@ -839,6 +847,7 @@ static VALUE cParser_initialize(int argc, VALUE *argv, VALUE self)
  *
  *  Parses the current JSON text _source_ and returns the complete data
  *  structure as a result.
+ *  It raises JSON::ParseError if fail to parse.
  */
 static VALUE cParser_parse(VALUE self)
 {
@@ -855,7 +864,7 @@ static VALUE cParser_parse(VALUE self)
   if (cs >= JSON_first_final && p == pe) {
     return result;
   } else {
-    rb_enc_raise(EXC_ENCODING eParserError, "%u: unexpected token at '%s'", __LINE__, p);
+    rb_enc_raise(EXC_ENCODING eParserError, "unexpected token at '%s'", p);
     return Qnil;
   }
 }
diff --git a/ext/nkf/nkf-utf8/nkf.c b/ext/nkf/nkf-utf8/nkf.c
index 08b372ffab..6888a43918 100644
--- a/ext/nkf/nkf-utf8/nkf.c
+++ b/ext/nkf/nkf-utf8/nkf.c
@@ -144,7 +144,7 @@ static void w_oconv(nkf_char c2, nkf_char c1);
 static void w_oconv16(nkf_char c2, nkf_char c1);
 static void w_oconv32(nkf_char c2, nkf_char c1);
 
-typedef struct {
+typedef const struct {
     const char *name;
     nkf_char (*iconv)(nkf_char c2, nkf_char c1, nkf_char c0);
     void (*oconv)(nkf_char c2, nkf_char c1);
@@ -158,10 +158,10 @@ nkf_native_encoding NkfEncodingUTF_8 =		{ "UTF-8", w_iconv, w_oconv };
 nkf_native_encoding NkfEncodingUTF_16 =		{ "UTF-16", w_iconv16, w_oconv16 };
 nkf_native_encoding NkfEncodingUTF_32 =		{ "UTF-32", w_iconv32, w_oconv32 };
 
-typedef struct {
-    const int id;
+typedef const struct {
+    int id;
     const char *name;
-    const nkf_native_encoding *base_encoding;
+    nkf_native_encoding *base_encoding;
 } nkf_encoding;
 
 nkf_encoding nkf_encoding_table[] = {
@@ -204,9 +204,9 @@ nkf_encoding nkf_encoding_table[] = {
     {-1,		NULL,			NULL}
 };
 
-struct {
+static const struct {
     const char *name;
-    const int id;
+    int id;
 } encoding_name_to_id_table[] = {
     {"US-ASCII",		ASCII},
     {"ASCII",			ASCII},
@@ -4286,7 +4286,7 @@ static const unsigned char *mime_pattern[] = {
 
 
 /* $B3:Ev$9$k%3!<%I$NM%@hEY$r>e$2$k$?$a$NL\0u(B */
-nkf_char (*mime_priority_func[])(nkf_char c2, nkf_char c1, nkf_char c0) = {
+static nkf_char (*const mime_priority_func[])(nkf_char c2, nkf_char c1, nkf_char c0) = {
     e_iconv, s_iconv, 0, 0, 0, 0, 0,
 #if defined(UTF8_INPUT_ENABLE)
     w_iconv, w_iconv,
diff --git a/ext/nkf/nkf.c b/ext/nkf/nkf.c
index 533f9b782f..c6ddee1976 100644
--- a/ext/nkf/nkf.c
+++ b/ext/nkf/nkf.c
@@ -65,11 +65,11 @@ rb_encoding* rb_nkf_enc_get(const char *name)
 {
     int idx = rb_enc_find_index(name);
     if (idx < 0) {
-	nkf_encoding *nkf_enc = nkf_enc_find(name);
-	idx = rb_enc_find_index(nkf_enc_name(nkf_enc_to_base_encoding(nkf_enc)));
-	if (idx < 0) {
-	    idx = rb_define_dummy_encoding(name);
-	}
+        nkf_encoding *nkf_enc = nkf_enc_find(name);
+        idx = rb_enc_find_index(nkf_enc_name(nkf_enc_to_base_encoding(nkf_enc)));
+        if (idx < 0) {
+            idx = rb_define_dummy_encoding(name);
+        }
     }
     return rb_enc_from_index(idx);
 }
@@ -83,40 +83,40 @@ int nkf_split_options(const char *arg)
     int is_single_quoted = FALSE;
     int is_double_quoted = FALSE;
     for(i = 0; arg[i]; i++){
-	if(j == 255){
-	    return -1;
-	}else if(is_single_quoted){
-	    if(arg[i] == '\''){
-		is_single_quoted = FALSE;
-	    }else{
-		option[j++] = arg[i];
-	    }
-	}else if(is_escaped){
-	    is_escaped = FALSE;
-	    option[j++] = arg[i];
-	}else if(arg[i] == '\\'){
-	    is_escaped = TRUE;
-	}else if(is_double_quoted){
-	    if(arg[i] == '"'){
-		is_double_quoted = FALSE;
-	    }else{
-		option[j++] = arg[i];
-	    }
-	}else if(arg[i] == '\''){
-	    is_single_quoted = TRUE;
-	}else if(arg[i] == '"'){
-	    is_double_quoted = TRUE;
-	}else if(arg[i] == ' '){
-	    option[j] = '\0';
-	    options(option);
-	    j = 0;
-	}else{
-	    option[j++] = arg[i];
-	}
+        if(j == 255){
+            return -1;
+        }else if(is_single_quoted){
+            if(arg[i] == '\''){
+                is_single_quoted = FALSE;
+            }else{
+                option[j++] = arg[i];
+            }
+        }else if(is_escaped){
+            is_escaped = FALSE;
+            option[j++] = arg[i];
+        }else if(arg[i] == '\\'){
+            is_escaped = TRUE;
+        }else if(is_double_quoted){
+            if(arg[i] == '"'){
+                is_double_quoted = FALSE;
+            }else{
+                option[j++] = arg[i];
+            }
+        }else if(arg[i] == '\''){
+            is_single_quoted = TRUE;
+        }else if(arg[i] == '"'){
+            is_double_quoted = TRUE;
+        }else if(arg[i] == ' '){
+            option[j] = '\0';
+            options(option);
+            j = 0;
+        }else{
+            option[j++] = arg[i];
+        }
     }
     if(j){
-	option[j] = '\0';
-	options(option);
+        option[j] = '\0';
+        options(option);
     }
     return count;
 }
@@ -170,9 +170,9 @@ rb_nkf_convert(VALUE obj, VALUE opt, VALUE src)
     rb_str_set_len(tmp, output_ctr);
 
     if (mimeout_f)
-	rb_enc_associate(tmp, rb_usascii_encoding());
+        rb_enc_associate(tmp, rb_usascii_encoding());
     else
-	rb_enc_associate(tmp, rb_nkf_enc_get(nkf_enc_name(output_encoding)));
+        rb_enc_associate(tmp, rb_nkf_enc_get(nkf_enc_name(output_encoding)));
 
     return tmp;
 }
@@ -274,7 +274,7 @@ rb_nkf_guess(VALUE obj, VALUE src)
  *
  *  {de/en}crypt ROT13/47
  *
- *  === -h[123] --hiragana --katakana --katakana-hiragana
+ *  === \-h[123] --hiragana --katakana --katakana-hiragana
  *
  *  [-h1 --hiragana] Katakana to Hiragana conversion.
  *
@@ -299,7 +299,7 @@ rb_nkf_guess(VALUE obj, VALUE src)
  *
  *  New line preserving line folding.
  *
- *  === -Z[0-3]
+ *  === \-Z[0-3]
  *
  *  Convert X0208 alphabet (Fullwidth Alphabets) to ASCII.
  *
@@ -318,7 +318,7 @@ rb_nkf_guess(VALUE obj, VALUE src)
  *  With <b>-x</b>, try to preserve X0208 kana and do not convert X0201 kana to X0208.
  *  In JIS output, ESC-(-I is used. In EUC output, SSO is used.
  *
- *  === -B[0-2]
+ *  === \-B[0-2]
  *
  *  Assume broken JIS-Kanji input, which lost ESC.
  *  Useful when your site is using old B-News Nihongo patch.
@@ -336,7 +336,7 @@ rb_nkf_guess(VALUE obj, VALUE src)
  *
  *  Delete \r in line feed, Add \r in line feed.
  *
- *  === -m[BQN0]
+ *  === \-m[BQN0]
  *
  *  MIME ISO-2022-JP/ISO8859-1 decode. (DEFAULT)
  *  To see ISO8859-1 (Latin-1) -l is necessary.
@@ -365,7 +365,7 @@ rb_nkf_guess(VALUE obj, VALUE src)
  *  Input and output code is ISO8859-1 (Latin-1) and ISO-2022-JP.
  *  <b>-s</b>, <b>-e</b> and <b>-x</b> are not compatible with this option.
  *
- *  === -L[uwm]
+ *  === \-L[uwm]
  *
  *  new line mode
  *  Without this option, nkf doesn't convert line breaks.
diff --git a/ext/nkf/nkf.gemspec b/ext/nkf/nkf.gemspec
index 2d77c71ff8..7f3bd4a4b1 100644
--- a/ext/nkf/nkf.gemspec
+++ b/ext/nkf/nkf.gemspec
@@ -1,6 +1,6 @@
 Gem::Specification.new do |spec|
   spec.name          = "nkf"
-  spec.version       = "0.1.1"
+  spec.version       = "0.1.2"
   spec.authors       = ["NARUSE Yui"]
   spec.email         = ["naruse@airemix.jp"]
 
diff --git a/ext/objspace/depend b/ext/objspace/depend
index 377b803d2a..52797664e0 100644
--- a/ext/objspace/depend
+++ b/ext/objspace/depend
@@ -158,12 +158,14 @@ object_tracing.o: $(hdrdir)/ruby/missing.h
 object_tracing.o: $(hdrdir)/ruby/ruby.h
 object_tracing.o: $(hdrdir)/ruby/st.h
 object_tracing.o: $(hdrdir)/ruby/subst.h
+object_tracing.o: $(top_srcdir)/gc.h
 object_tracing.o: $(top_srcdir)/internal.h
 object_tracing.o: object_tracing.c
 object_tracing.o: objspace.h
 objspace.o: $(RUBY_EXTCONF_H)
 objspace.o: $(arch_hdrdir)/ruby/config.h
 objspace.o: $(hdrdir)/ruby/assert.h
+objspace.o: $(hdrdir)/ruby/atomic.h
 objspace.o: $(hdrdir)/ruby/backward.h
 objspace.o: $(hdrdir)/ruby/backward/2/assume.h
 objspace.o: $(hdrdir)/ruby/backward/2/attributes.h
@@ -336,10 +338,16 @@ objspace.o: $(hdrdir)/ruby/regex.h
 objspace.o: $(hdrdir)/ruby/ruby.h
 objspace.o: $(hdrdir)/ruby/st.h
 objspace.o: $(hdrdir)/ruby/subst.h
+objspace.o: $(hdrdir)/ruby/thread_native.h
+objspace.o: $(top_srcdir)/ccan/check_type/check_type.h
+objspace.o: $(top_srcdir)/ccan/container_of/container_of.h
+objspace.o: $(top_srcdir)/ccan/list/list.h
+objspace.o: $(top_srcdir)/ccan/str/str.h
 objspace.o: $(top_srcdir)/gc.h
 objspace.o: $(top_srcdir)/id_table.h
 objspace.o: $(top_srcdir)/internal.h
 objspace.o: $(top_srcdir)/internal/array.h
+objspace.o: $(top_srcdir)/internal/basic_operators.h
 objspace.o: $(top_srcdir)/internal/class.h
 objspace.o: $(top_srcdir)/internal/compilers.h
 objspace.o: $(top_srcdir)/internal/gc.h
@@ -348,9 +356,17 @@ objspace.o: $(top_srcdir)/internal/imemo.h
 objspace.o: $(top_srcdir)/internal/sanitizers.h
 objspace.o: $(top_srcdir)/internal/serial.h
 objspace.o: $(top_srcdir)/internal/static_assert.h
+objspace.o: $(top_srcdir)/internal/vm.h
 objspace.o: $(top_srcdir)/internal/warnings.h
+objspace.o: $(top_srcdir)/method.h
 objspace.o: $(top_srcdir)/node.h
+objspace.o: $(top_srcdir)/ruby_assert.h
+objspace.o: $(top_srcdir)/ruby_atomic.h
+objspace.o: $(top_srcdir)/shape.h
 objspace.o: $(top_srcdir)/symbol.h
+objspace.o: $(top_srcdir)/thread_pthread.h
+objspace.o: $(top_srcdir)/vm_core.h
+objspace.o: $(top_srcdir)/vm_opts.h
 objspace.o: objspace.c
 objspace.o: {$(VPATH)}id.h
 objspace_dump.o: $(RUBY_EXTCONF_H)
@@ -533,10 +549,13 @@ objspace_dump.o: $(top_srcdir)/ccan/check_type/check_type.h
 objspace_dump.o: $(top_srcdir)/ccan/container_of/container_of.h
 objspace_dump.o: $(top_srcdir)/ccan/list/list.h
 objspace_dump.o: $(top_srcdir)/ccan/str/str.h
-objspace_dump.o: $(top_srcdir)/darray.h
+objspace_dump.o: $(top_srcdir)/constant.h
 objspace_dump.o: $(top_srcdir)/gc.h
+objspace_dump.o: $(top_srcdir)/id_table.h
 objspace_dump.o: $(top_srcdir)/internal.h
 objspace_dump.o: $(top_srcdir)/internal/array.h
+objspace_dump.o: $(top_srcdir)/internal/basic_operators.h
+objspace_dump.o: $(top_srcdir)/internal/class.h
 objspace_dump.o: $(top_srcdir)/internal/compilers.h
 objspace_dump.o: $(top_srcdir)/internal/gc.h
 objspace_dump.o: $(top_srcdir)/internal/hash.h
@@ -545,12 +564,15 @@ objspace_dump.o: $(top_srcdir)/internal/sanitizers.h
 objspace_dump.o: $(top_srcdir)/internal/serial.h
 objspace_dump.o: $(top_srcdir)/internal/static_assert.h
 objspace_dump.o: $(top_srcdir)/internal/string.h
+objspace_dump.o: $(top_srcdir)/internal/variable.h
 objspace_dump.o: $(top_srcdir)/internal/vm.h
 objspace_dump.o: $(top_srcdir)/internal/warnings.h
 objspace_dump.o: $(top_srcdir)/method.h
 objspace_dump.o: $(top_srcdir)/node.h
 objspace_dump.o: $(top_srcdir)/ruby_assert.h
 objspace_dump.o: $(top_srcdir)/ruby_atomic.h
+objspace_dump.o: $(top_srcdir)/shape.h
+objspace_dump.o: $(top_srcdir)/symbol.h
 objspace_dump.o: $(top_srcdir)/thread_pthread.h
 objspace_dump.o: $(top_srcdir)/vm_core.h
 objspace_dump.o: $(top_srcdir)/vm_opts.h
diff --git a/ext/objspace/lib/objspace.rb b/ext/objspace/lib/objspace.rb
index 0298b0646c..6865fdda4c 100644
--- a/ext/objspace/lib/objspace.rb
+++ b/ext/objspace/lib/objspace.rb
@@ -6,14 +6,15 @@ module ObjectSpace
   class << self
     private :_dump
     private :_dump_all
+    private :_dump_shapes
   end
 
   module_function
 
   # call-seq:
-  #   ObjectSpace.dump(obj[, output: :string]) # => "{ ... }"
-  #   ObjectSpace.dump(obj, output: :file)     # => #<File:/tmp/rubyobj20131125-88733-1xkfmpv.json>
-  #   ObjectSpace.dump(obj, output: :stdout)   # => nil
+  #   ObjectSpace.dump(obj[, output: :string]) -> "{ ... }"
+  #   ObjectSpace.dump(obj, output: :file) -> #<File:/tmp/rubyobj20131125-88733-1xkfmpv.json>
+  #   ObjectSpace.dump(obj, output: :stdout) -> nil
   #
   # Dump the contents of a ruby object as JSON.
   #
@@ -42,38 +43,88 @@ module ObjectSpace
   end
 
 
-  #  call-seq:
-  #    ObjectSpace.dump_all([output: :file]) # => #<File:/tmp/rubyheap20131125-88469-laoj3v.json>
-  #    ObjectSpace.dump_all(output: :stdout) # => nil
-  #    ObjectSpace.dump_all(output: :string) # => "{...}\n{...}\n..."
-  #    ObjectSpace.dump_all(output:
-  #      File.open('heap.json','w'))         # => #<File:heap.json>
-  #    ObjectSpace.dump_all(output: :string,
-  #      since: 42)                          # => "{...}\n{...}\n..."
+  # call-seq:
+  #   ObjectSpace.dump_all([output: :file]) -> #<File:/tmp/rubyheap20131125-88469-laoj3v.json>
+  #   ObjectSpace.dump_all(output: :stdout) -> nil
+  #   ObjectSpace.dump_all(output: :string) -> "{...}\n{...}\n..."
+  #   ObjectSpace.dump_all(output: File.open('heap.json','w')) -> #<File:heap.json>
+  #   ObjectSpace.dump_all(output: :string, since: 42) -> "{...}\n{...}\n..."
+  #
+  # Dump the contents of the ruby heap as JSON.
+  #
+  # _full_ must be a boolean. If true all heap slots are dumped including the empty ones (T_NONE).
+  #
+  # _since_ must be a non-negative integer or +nil+.
   #
-  #  Dump the contents of the ruby heap as JSON.
+  # If _since_ is a positive integer, only objects of that generation and
+  # newer generations are dumped. The current generation can be accessed using
+  # GC::count. Objects that were allocated without object allocation tracing enabled
+  # are ignored. See ::trace_object_allocations for more information and
+  # examples.
   #
-  #  _since_ must be a non-negative integer or +nil+.
+  # If _since_ is omitted or is +nil+, all objects are dumped.
   #
-  #  If _since_ is a positive integer, only objects of that generation and
-  #  newer generations are dumped. The current generation can be accessed using
-  #  GC::count.
+  # _shapes_ must be a boolean or a non-negative integer.
   #
-  #  Objects that were allocated without object allocation tracing enabled
-  #  are ignored. See ::trace_object_allocations for more information and
-  #  examples.
+  # If _shapes_ is a positive integer, only shapes newer than the provided
+  # shape id are dumped. The current shape_id can be accessed using <tt>RubyVM.stat(:next_shape_id)</tt>.
   #
-  #  If _since_ is omitted or is +nil+, all objects are dumped.
+  # If _shapes_ is +false+, no shapes are dumped.
+  #
+  # To only dump objects allocated past a certain point you can combine _since_ and _shapes_:
+  #   ObjectSpace.trace_object_allocations
+  #   GC.start
+  #   gc_generation = GC.count
+  #   shape_generation = RubyVM.stat(:next_shape_id)
+  #   call_method_to_instrument
+  #   ObjectSpace.dump_all(since: gc_generation, shapes: shape_generation)
+  #
+  # This method is only expected to work with C Ruby.
+  # This is an experimental method and is subject to change.
+  # In particular, the function signature and output format are
+  # not guaranteed to be compatible in future versions of ruby.
+  def dump_all(output: :file, full: false, since: nil, shapes: true)
+    out = case output
+    when :file, nil
+      require 'tempfile'
+      Tempfile.create(%w(rubyheap .json))
+    when :stdout
+      STDOUT
+    when :string
+      +''
+    when IO
+      output
+    else
+      raise ArgumentError, "wrong output option: #{output.inspect}"
+    end
+
+    shapes = 0 if shapes == true
+    ret = _dump_all(out, full, since, shapes)
+    return nil if output == :stdout
+    ret
+  end
+
+  #  call-seq:
+  #    ObjectSpace.dump_shapes([output: :file]) -> #<File:/tmp/rubyshapes20131125-88469-laoj3v.json>
+  #    ObjectSpace.dump_shapes(output: :stdout) -> nil
+  #    ObjectSpace.dump_shapes(output: :string) -> "{...}\n{...}\n..."
+  #    ObjectSpace.dump_shapes(output: File.open('shapes.json','w')) -> #<File:shapes.json>
+  #    ObjectSpace.dump_all(output: :string, since: 42) -> "{...}\n{...}\n..."
+  #
+  #  Dump the contents of the ruby shape tree as JSON.
+  #
+  #  If _shapes_ is a positive integer, only shapes newer than the provided
+  #  shape id are dumped. The current shape_id can be accessed using <tt>RubyVM.stat(:next_shape_id)</tt>.
   #
   #  This method is only expected to work with C Ruby.
   #  This is an experimental method and is subject to change.
   #  In particular, the function signature and output format are
   #  not guaranteed to be compatible in future versions of ruby.
-  def dump_all(output: :file, full: false, since: nil)
+  def dump_shapes(output: :file, since: 0)
     out = case output
     when :file, nil
       require 'tempfile'
-      Tempfile.create(%w(rubyheap .json))
+      Tempfile.create(%w(rubyshapes .json))
     when :stdout
       STDOUT
     when :string
@@ -84,7 +135,7 @@ module ObjectSpace
       raise ArgumentError, "wrong output option: #{output.inspect}"
     end
 
-    ret = _dump_all(out, full, since)
+    ret = _dump_shapes(out, since)
     return nil if output == :stdout
     ret
   end
diff --git a/ext/objspace/object_tracing.c b/ext/objspace/object_tracing.c
index 66d6baa491..8c54d51eab 100644
--- a/ext/objspace/object_tracing.c
+++ b/ext/objspace/object_tracing.c
@@ -13,6 +13,7 @@
 
 **********************************************************************/
 
+#include "gc.h"
 #include "internal.h"
 #include "ruby/debug.h"
 #include "objspace.h"
@@ -31,24 +32,24 @@ static const char *
 make_unique_str(st_table *tbl, const char *str, long len)
 {
     if (!str) {
-	return NULL;
+        return NULL;
     }
     else {
-	st_data_t n;
-	char *result;
-
-	if (st_lookup(tbl, (st_data_t)str, &n)) {
-	    st_insert(tbl, (st_data_t)str, n+1);
-	    st_get_key(tbl, (st_data_t)str, &n);
-	    result = (char *)n;
-	}
-	else {
-	    result = (char *)ruby_xmalloc(len+1);
-	    strncpy(result, str, len);
-	    result[len] = 0;
-	    st_add_direct(tbl, (st_data_t)result, 1);
-	}
-	return result;
+        st_data_t n;
+        char *result;
+
+        if (st_lookup(tbl, (st_data_t)str, &n)) {
+            st_insert(tbl, (st_data_t)str, n+1);
+            st_get_key(tbl, (st_data_t)str, &n);
+            result = (char *)n;
+        }
+        else {
+            result = (char *)ruby_xmalloc(len+1);
+            strncpy(result, str, len);
+            result[len] = 0;
+            st_add_direct(tbl, (st_data_t)result, 1);
+        }
+        return result;
     }
 }
 
@@ -56,17 +57,17 @@ static void
 delete_unique_str(st_table *tbl, const char *str)
 {
     if (str) {
-	st_data_t n;
-
-	st_lookup(tbl, (st_data_t)str, &n);
-	if (n == 1) {
-	    n = (st_data_t)str;
-	    st_delete(tbl, &n, 0);
-	    ruby_xfree((char *)n);
-	}
-	else {
-	    st_insert(tbl, (st_data_t)str, n-1);
-	}
+        st_data_t n;
+
+        st_lookup(tbl, (st_data_t)str, &n);
+        if (n == 1) {
+            n = (st_data_t)str;
+            st_delete(tbl, &n, 0);
+            ruby_xfree((char *)n);
+        }
+        else {
+            st_insert(tbl, (st_data_t)str, n-1);
+        }
     }
 }
 
@@ -87,18 +88,18 @@ newobj_i(VALUE tpval, void *data)
     st_data_t v;
 
     if (st_lookup(arg->object_table, (st_data_t)obj, &v)) {
-	info = (struct allocation_info *)v;
-	if (arg->keep_remains) {
-	    if (info->living) {
-		/* do nothing. there is possibility to keep living if FREEOBJ events while suppressing tracing */
-	    }
-	}
-	/* reuse info */
-	delete_unique_str(arg->str_table, info->path);
-	delete_unique_str(arg->str_table, info->class_path);
+        info = (struct allocation_info *)v;
+        if (arg->keep_remains) {
+            if (info->living) {
+                /* do nothing. there is possibility to keep living if FREEOBJ events while suppressing tracing */
+            }
+        }
+        /* reuse info */
+        delete_unique_str(arg->str_table, info->path);
+        delete_unique_str(arg->str_table, info->class_path);
     }
     else {
-	info = (struct allocation_info *)ruby_xmalloc(sizeof(struct allocation_info));
+        info = (struct allocation_info *)ruby_xmalloc(sizeof(struct allocation_info));
     }
     info->living = 1;
     info->flags = RBASIC(obj)->flags;
@@ -121,20 +122,26 @@ freeobj_i(VALUE tpval, void *data)
     st_data_t v;
     struct allocation_info *info;
 
+    /* Modifying the st table can cause allocations, which can trigger GC.
+     * Since freeobj_i is called during GC, it must not trigger another GC. */
+    VALUE gc_disabled = rb_gc_disable_no_rest();
+
     if (arg->keep_remains) {
-	if (st_lookup(arg->object_table, obj, &v)) {
-	    info = (struct allocation_info *)v;
-	    info->living = 0;
-	}
+        if (st_lookup(arg->object_table, obj, &v)) {
+            info = (struct allocation_info *)v;
+            info->living = 0;
+        }
     }
     else {
-	if (st_delete(arg->object_table, &obj, &v)) {
-	    info = (struct allocation_info *)v;
-	    delete_unique_str(arg->str_table, info->path);
-	    delete_unique_str(arg->str_table, info->class_path);
-	    ruby_xfree(info);
-	}
+        if (st_delete(arg->object_table, &obj, &v)) {
+            info = (struct allocation_info *)v;
+            delete_unique_str(arg->str_table, info->path);
+            delete_unique_str(arg->str_table, info->class_path);
+            ruby_xfree(info);
+        }
     }
+
+    if (gc_disabled == Qfalse) rb_gc_enable();
 }
 
 static int
@@ -236,12 +243,12 @@ get_traceobj_arg(void)
         VALUE obj = TypedData_Make_Struct(rb_cObject, struct traceobj_arg, &allocation_info_tracer_type, tmp_trace_arg);
         traceobj_arg = obj;
         rb_gc_register_mark_object(traceobj_arg);
-	tmp_trace_arg->running = 0;
-	tmp_trace_arg->keep_remains = tmp_keep_remains;
-	tmp_trace_arg->newobj_trace = 0;
-	tmp_trace_arg->freeobj_trace = 0;
-	tmp_trace_arg->object_table = st_init_numtable();
-	tmp_trace_arg->str_table = st_init_strtable();
+        tmp_trace_arg->running = 0;
+        tmp_trace_arg->keep_remains = tmp_keep_remains;
+        tmp_trace_arg->newobj_trace = 0;
+        tmp_trace_arg->freeobj_trace = 0;
+        tmp_trace_arg->object_table = st_init_numtable();
+        tmp_trace_arg->str_table = st_init_strtable();
     }
     return tmp_trace_arg;
 }
@@ -258,15 +265,15 @@ trace_object_allocations_start(VALUE self)
     struct traceobj_arg *arg = get_traceobj_arg();
 
     if (arg->running++ > 0) {
-	/* do nothing */
+        /* do nothing */
     }
     else {
-	if (arg->newobj_trace == 0) {
-	    arg->newobj_trace = rb_tracepoint_new(0, RUBY_INTERNAL_EVENT_NEWOBJ, newobj_i, arg);
-	    arg->freeobj_trace = rb_tracepoint_new(0, RUBY_INTERNAL_EVENT_FREEOBJ, freeobj_i, arg);
-	}
-	rb_tracepoint_enable(arg->newobj_trace);
-	rb_tracepoint_enable(arg->freeobj_trace);
+        if (arg->newobj_trace == 0) {
+            arg->newobj_trace = rb_tracepoint_new(0, RUBY_INTERNAL_EVENT_NEWOBJ, newobj_i, arg);
+            arg->freeobj_trace = rb_tracepoint_new(0, RUBY_INTERNAL_EVENT_FREEOBJ, freeobj_i, arg);
+        }
+        rb_tracepoint_enable(arg->newobj_trace);
+        rb_tracepoint_enable(arg->freeobj_trace);
     }
 
     return Qnil;
@@ -287,7 +294,7 @@ trace_object_allocations_stop(VALUE self)
     struct traceobj_arg *arg = get_traceobj_arg();
 
     if (arg->running > 0) {
-	arg->running--;
+        arg->running--;
     }
 
     if (arg->running == 0) {
@@ -374,8 +381,8 @@ object_allocations_reporter_i(st_data_t key, st_data_t val, st_data_t ptr)
     else                  fprintf(out, "C: %p", (void *)info->klass);
     fprintf(out, "@%s:%lu", info->path ? info->path : "", info->line);
     if (!NIL_P(info->mid)) {
-	VALUE m = rb_sym2str(info->mid);
-	fprintf(out, " (%s)", RSTRING_PTR(m));
+        VALUE m = rb_sym2str(info->mid);
+        fprintf(out, " (%s)", RSTRING_PTR(m));
     }
     fprintf(out, ")\n");
 
@@ -387,7 +394,7 @@ object_allocations_reporter(FILE *out, void *ptr)
 {
     fprintf(out, "== object_allocations_reporter: START\n");
     if (tmp_trace_arg) {
-	st_foreach(tmp_trace_arg->object_table, object_allocations_reporter_i, (st_data_t)out);
+        st_foreach(tmp_trace_arg->object_table, object_allocations_reporter_i, (st_data_t)out);
     }
     fprintf(out, "== object_allocations_reporter: END\n");
 }
@@ -397,8 +404,8 @@ trace_object_allocations_debug_start(VALUE self)
 {
     tmp_keep_remains = 1;
     if (object_allocations_reporter_registered == 0) {
-	object_allocations_reporter_registered = 1;
-	rb_bug_reporter_add(object_allocations_reporter, 0);
+        object_allocations_reporter_registered = 1;
+        rb_bug_reporter_add(object_allocations_reporter, 0);
     }
 
     return trace_object_allocations_start(self);
@@ -408,10 +415,10 @@ static struct allocation_info *
 lookup_allocation_info(VALUE obj)
 {
     if (tmp_trace_arg) {
-	st_data_t info;
-	if (st_lookup(tmp_trace_arg->object_table, obj, &info)) {
-	    return (struct allocation_info *)info;
-	}
+        st_data_t info;
+        if (st_lookup(tmp_trace_arg->object_table, obj, &info)) {
+            return (struct allocation_info *)info;
+        }
     }
     return NULL;
 }
@@ -435,10 +442,10 @@ allocation_sourcefile(VALUE self, VALUE obj)
     struct allocation_info *info = lookup_allocation_info(obj);
 
     if (info && info->path) {
-	return rb_str_new2(info->path);
+        return rb_str_new2(info->path);
     }
     else {
-	return Qnil;
+        return Qnil;
     }
 }
 
@@ -455,10 +462,10 @@ allocation_sourceline(VALUE self, VALUE obj)
     struct allocation_info *info = lookup_allocation_info(obj);
 
     if (info) {
-	return INT2FIX(info->line);
+        return INT2FIX(info->line);
     }
     else {
-	return Qnil;
+        return Qnil;
     }
 }
 
@@ -486,10 +493,10 @@ allocation_class_path(VALUE self, VALUE obj)
     struct allocation_info *info = lookup_allocation_info(obj);
 
     if (info && info->class_path) {
-	return rb_str_new2(info->class_path);
+        return rb_str_new2(info->class_path);
     }
     else {
-	return Qnil;
+        return Qnil;
     }
 }
 
@@ -518,10 +525,10 @@ allocation_method_id(VALUE self, VALUE obj)
 {
     struct allocation_info *info = lookup_allocation_info(obj);
     if (info) {
-	return info->mid;
+        return info->mid;
     }
     else {
-	return Qnil;
+        return Qnil;
     }
 }
 
@@ -550,10 +557,10 @@ allocation_generation(VALUE self, VALUE obj)
 {
     struct allocation_info *info = lookup_allocation_info(obj);
     if (info) {
-	return SIZET2NUM(info->generation);
+        return SIZET2NUM(info->generation);
     }
     else {
-	return Qnil;
+        return Qnil;
     }
 }
 
diff --git a/ext/objspace/objspace.c b/ext/objspace/objspace.c
index bd80e540cf..ca08604c95 100644
--- a/ext/objspace/objspace.c
+++ b/ext/objspace/objspace.c
@@ -62,9 +62,9 @@ total_i(VALUE v, void *ptr)
     struct total_data *data = (struct total_data *)ptr;
 
     if (!rb_objspace_internal_object_p(v)) {
-          if (data->klass == 0 || rb_obj_is_kind_of(v, data->klass)) {
-              data->total += rb_obj_memsize_of(v);
-          }
+        if (data->klass == 0 || rb_obj_is_kind_of(v, data->klass)) {
+            data->total += rb_obj_memsize_of(v);
+        }
     }
 }
 
@@ -140,7 +140,7 @@ memsize_of_all_m(int argc, VALUE *argv, VALUE self)
     struct total_data data = {0, 0};
 
     if (argc > 0) {
-	rb_scan_args(argc, argv, "01", &data.klass);
+        rb_scan_args(argc, argv, "01", &data.klass);
     }
 
     each_object_with_flags(total_i, &data);
@@ -190,33 +190,33 @@ type2sym(enum ruby_value_type i)
     VALUE type;
     switch (i) {
 #define CASE_TYPE(t) case t: type = ID2SYM(rb_intern(#t)); break;
-	CASE_TYPE(T_NONE);
-	CASE_TYPE(T_OBJECT);
-	CASE_TYPE(T_CLASS);
-	CASE_TYPE(T_MODULE);
-	CASE_TYPE(T_FLOAT);
-	CASE_TYPE(T_STRING);
-	CASE_TYPE(T_REGEXP);
-	CASE_TYPE(T_ARRAY);
-	CASE_TYPE(T_HASH);
-	CASE_TYPE(T_STRUCT);
-	CASE_TYPE(T_BIGNUM);
-	CASE_TYPE(T_FILE);
-	CASE_TYPE(T_DATA);
-	CASE_TYPE(T_MATCH);
-	CASE_TYPE(T_COMPLEX);
-	CASE_TYPE(T_RATIONAL);
-	CASE_TYPE(T_NIL);
-	CASE_TYPE(T_TRUE);
-	CASE_TYPE(T_FALSE);
-	CASE_TYPE(T_SYMBOL);
-	CASE_TYPE(T_FIXNUM);
-	CASE_TYPE(T_UNDEF);
-	CASE_TYPE(T_IMEMO);
-	CASE_TYPE(T_NODE);
-	CASE_TYPE(T_ICLASS);
+        CASE_TYPE(T_NONE);
+        CASE_TYPE(T_OBJECT);
+        CASE_TYPE(T_CLASS);
+        CASE_TYPE(T_MODULE);
+        CASE_TYPE(T_FLOAT);
+        CASE_TYPE(T_STRING);
+        CASE_TYPE(T_REGEXP);
+        CASE_TYPE(T_ARRAY);
+        CASE_TYPE(T_HASH);
+        CASE_TYPE(T_STRUCT);
+        CASE_TYPE(T_BIGNUM);
+        CASE_TYPE(T_FILE);
+        CASE_TYPE(T_DATA);
+        CASE_TYPE(T_MATCH);
+        CASE_TYPE(T_COMPLEX);
+        CASE_TYPE(T_RATIONAL);
+        CASE_TYPE(T_NIL);
+        CASE_TYPE(T_TRUE);
+        CASE_TYPE(T_FALSE);
+        CASE_TYPE(T_SYMBOL);
+        CASE_TYPE(T_FIXNUM);
+        CASE_TYPE(T_UNDEF);
+        CASE_TYPE(T_IMEMO);
+        CASE_TYPE(T_NODE);
+        CASE_TYPE(T_ICLASS);
         CASE_TYPE(T_MOVED);
-	CASE_TYPE(T_ZOMBIE);
+        CASE_TYPE(T_ZOMBIE);
 #undef CASE_TYPE
       default: rb_bug("type2sym: unknown type (%d)", i);
     }
@@ -255,17 +255,17 @@ count_objects_size(int argc, VALUE *argv, VALUE os)
     VALUE hash = setup_hash(argc, argv);
 
     for (i = 0; i <= T_MASK; i++) {
-	counts[i] = 0;
+        counts[i] = 0;
     }
 
     each_object_with_flags(cos_i, &counts[0]);
 
     for (i = 0; i <= T_MASK; i++) {
-	if (counts[i]) {
-	    VALUE type = type2sym(i);
-	    total += counts[i];
-	    rb_hash_aset(hash, type, SIZET2NUM(counts[i]));
-	}
+        if (counts[i]) {
+            VALUE type = type2sym(i);
+            total += counts[i];
+            rb_hash_aset(hash, type, SIZET2NUM(counts[i]));
+        }
     }
     rb_hash_aset(hash, ID2SYM(rb_intern("TOTAL")), SIZET2NUM(total));
     return hash;
@@ -379,127 +379,128 @@ count_nodes(int argc, VALUE *argv, VALUE os)
     VALUE hash = setup_hash(argc, argv);
 
     for (i = 0; i <= NODE_LAST; i++) {
-	nodes[i] = 0;
+        nodes[i] = 0;
     }
 
     each_object_with_flags(cn_i, &nodes[0]);
 
     for (i=0; i<NODE_LAST; i++) {
-	if (nodes[i] != 0) {
-	    VALUE node;
-	    switch (i) {
+        if (nodes[i] != 0) {
+            VALUE node;
+            switch (i) {
 #define COUNT_NODE(n) case n: node = ID2SYM(rb_intern(#n)); goto set
-		COUNT_NODE(NODE_SCOPE);
-		COUNT_NODE(NODE_BLOCK);
-		COUNT_NODE(NODE_IF);
-		COUNT_NODE(NODE_UNLESS);
-		COUNT_NODE(NODE_CASE);
-		COUNT_NODE(NODE_CASE2);
-		COUNT_NODE(NODE_CASE3);
-		COUNT_NODE(NODE_WHEN);
-		COUNT_NODE(NODE_IN);
-		COUNT_NODE(NODE_WHILE);
-		COUNT_NODE(NODE_UNTIL);
-		COUNT_NODE(NODE_ITER);
-		COUNT_NODE(NODE_FOR);
-		COUNT_NODE(NODE_FOR_MASGN);
-		COUNT_NODE(NODE_BREAK);
-		COUNT_NODE(NODE_NEXT);
-		COUNT_NODE(NODE_REDO);
-		COUNT_NODE(NODE_RETRY);
-		COUNT_NODE(NODE_BEGIN);
-		COUNT_NODE(NODE_RESCUE);
-		COUNT_NODE(NODE_RESBODY);
-		COUNT_NODE(NODE_ENSURE);
-		COUNT_NODE(NODE_AND);
-		COUNT_NODE(NODE_OR);
-		COUNT_NODE(NODE_MASGN);
-		COUNT_NODE(NODE_LASGN);
-		COUNT_NODE(NODE_DASGN);
-		COUNT_NODE(NODE_GASGN);
-		COUNT_NODE(NODE_IASGN);
-		COUNT_NODE(NODE_CDECL);
-		COUNT_NODE(NODE_CVASGN);
-		COUNT_NODE(NODE_OP_ASGN1);
-		COUNT_NODE(NODE_OP_ASGN2);
-		COUNT_NODE(NODE_OP_ASGN_AND);
-		COUNT_NODE(NODE_OP_ASGN_OR);
-		COUNT_NODE(NODE_OP_CDECL);
-		COUNT_NODE(NODE_CALL);
-		COUNT_NODE(NODE_OPCALL);
-		COUNT_NODE(NODE_FCALL);
-		COUNT_NODE(NODE_VCALL);
-		COUNT_NODE(NODE_QCALL);
-		COUNT_NODE(NODE_SUPER);
-		COUNT_NODE(NODE_ZSUPER);
-		COUNT_NODE(NODE_LIST);
-		COUNT_NODE(NODE_ZLIST);
-		COUNT_NODE(NODE_VALUES);
-		COUNT_NODE(NODE_HASH);
-		COUNT_NODE(NODE_RETURN);
-		COUNT_NODE(NODE_YIELD);
-		COUNT_NODE(NODE_LVAR);
-		COUNT_NODE(NODE_DVAR);
-		COUNT_NODE(NODE_GVAR);
-		COUNT_NODE(NODE_IVAR);
-		COUNT_NODE(NODE_CONST);
-		COUNT_NODE(NODE_CVAR);
-		COUNT_NODE(NODE_NTH_REF);
-		COUNT_NODE(NODE_BACK_REF);
-		COUNT_NODE(NODE_MATCH);
-		COUNT_NODE(NODE_MATCH2);
-		COUNT_NODE(NODE_MATCH3);
-		COUNT_NODE(NODE_LIT);
-		COUNT_NODE(NODE_STR);
-		COUNT_NODE(NODE_DSTR);
-		COUNT_NODE(NODE_XSTR);
-		COUNT_NODE(NODE_DXSTR);
-		COUNT_NODE(NODE_EVSTR);
-		COUNT_NODE(NODE_DREGX);
-		COUNT_NODE(NODE_ONCE);
-		COUNT_NODE(NODE_ARGS);
-		COUNT_NODE(NODE_ARGS_AUX);
-		COUNT_NODE(NODE_OPT_ARG);
-		COUNT_NODE(NODE_KW_ARG);
-		COUNT_NODE(NODE_POSTARG);
-		COUNT_NODE(NODE_ARGSCAT);
-		COUNT_NODE(NODE_ARGSPUSH);
-		COUNT_NODE(NODE_SPLAT);
-		COUNT_NODE(NODE_BLOCK_PASS);
-		COUNT_NODE(NODE_DEFN);
-		COUNT_NODE(NODE_DEFS);
-		COUNT_NODE(NODE_ALIAS);
-		COUNT_NODE(NODE_VALIAS);
-		COUNT_NODE(NODE_UNDEF);
-		COUNT_NODE(NODE_CLASS);
-		COUNT_NODE(NODE_MODULE);
-		COUNT_NODE(NODE_SCLASS);
-		COUNT_NODE(NODE_COLON2);
-		COUNT_NODE(NODE_COLON3);
-		COUNT_NODE(NODE_DOT2);
-		COUNT_NODE(NODE_DOT3);
-		COUNT_NODE(NODE_FLIP2);
-		COUNT_NODE(NODE_FLIP3);
-		COUNT_NODE(NODE_SELF);
-		COUNT_NODE(NODE_NIL);
-		COUNT_NODE(NODE_TRUE);
-		COUNT_NODE(NODE_FALSE);
-		COUNT_NODE(NODE_ERRINFO);
-		COUNT_NODE(NODE_DEFINED);
-		COUNT_NODE(NODE_POSTEXE);
-		COUNT_NODE(NODE_DSYM);
-		COUNT_NODE(NODE_ATTRASGN);
-		COUNT_NODE(NODE_LAMBDA);
-		COUNT_NODE(NODE_ARYPTN);
-		COUNT_NODE(NODE_FNDPTN);
-		COUNT_NODE(NODE_HSHPTN);
+                COUNT_NODE(NODE_SCOPE);
+                COUNT_NODE(NODE_BLOCK);
+                COUNT_NODE(NODE_IF);
+                COUNT_NODE(NODE_UNLESS);
+                COUNT_NODE(NODE_CASE);
+                COUNT_NODE(NODE_CASE2);
+                COUNT_NODE(NODE_CASE3);
+                COUNT_NODE(NODE_WHEN);
+                COUNT_NODE(NODE_IN);
+                COUNT_NODE(NODE_WHILE);
+                COUNT_NODE(NODE_UNTIL);
+                COUNT_NODE(NODE_ITER);
+                COUNT_NODE(NODE_FOR);
+                COUNT_NODE(NODE_FOR_MASGN);
+                COUNT_NODE(NODE_BREAK);
+                COUNT_NODE(NODE_NEXT);
+                COUNT_NODE(NODE_REDO);
+                COUNT_NODE(NODE_RETRY);
+                COUNT_NODE(NODE_BEGIN);
+                COUNT_NODE(NODE_RESCUE);
+                COUNT_NODE(NODE_RESBODY);
+                COUNT_NODE(NODE_ENSURE);
+                COUNT_NODE(NODE_AND);
+                COUNT_NODE(NODE_OR);
+                COUNT_NODE(NODE_MASGN);
+                COUNT_NODE(NODE_LASGN);
+                COUNT_NODE(NODE_DASGN);
+                COUNT_NODE(NODE_GASGN);
+                COUNT_NODE(NODE_IASGN);
+                COUNT_NODE(NODE_CDECL);
+                COUNT_NODE(NODE_CVASGN);
+                COUNT_NODE(NODE_OP_ASGN1);
+                COUNT_NODE(NODE_OP_ASGN2);
+                COUNT_NODE(NODE_OP_ASGN_AND);
+                COUNT_NODE(NODE_OP_ASGN_OR);
+                COUNT_NODE(NODE_OP_CDECL);
+                COUNT_NODE(NODE_CALL);
+                COUNT_NODE(NODE_OPCALL);
+                COUNT_NODE(NODE_FCALL);
+                COUNT_NODE(NODE_VCALL);
+                COUNT_NODE(NODE_QCALL);
+                COUNT_NODE(NODE_SUPER);
+                COUNT_NODE(NODE_ZSUPER);
+                COUNT_NODE(NODE_LIST);
+                COUNT_NODE(NODE_ZLIST);
+                COUNT_NODE(NODE_VALUES);
+                COUNT_NODE(NODE_HASH);
+                COUNT_NODE(NODE_RETURN);
+                COUNT_NODE(NODE_YIELD);
+                COUNT_NODE(NODE_LVAR);
+                COUNT_NODE(NODE_DVAR);
+                COUNT_NODE(NODE_GVAR);
+                COUNT_NODE(NODE_IVAR);
+                COUNT_NODE(NODE_CONST);
+                COUNT_NODE(NODE_CVAR);
+                COUNT_NODE(NODE_NTH_REF);
+                COUNT_NODE(NODE_BACK_REF);
+                COUNT_NODE(NODE_MATCH);
+                COUNT_NODE(NODE_MATCH2);
+                COUNT_NODE(NODE_MATCH3);
+                COUNT_NODE(NODE_LIT);
+                COUNT_NODE(NODE_STR);
+                COUNT_NODE(NODE_DSTR);
+                COUNT_NODE(NODE_XSTR);
+                COUNT_NODE(NODE_DXSTR);
+                COUNT_NODE(NODE_EVSTR);
+                COUNT_NODE(NODE_DREGX);
+                COUNT_NODE(NODE_ONCE);
+                COUNT_NODE(NODE_ARGS);
+                COUNT_NODE(NODE_ARGS_AUX);
+                COUNT_NODE(NODE_OPT_ARG);
+                COUNT_NODE(NODE_KW_ARG);
+                COUNT_NODE(NODE_POSTARG);
+                COUNT_NODE(NODE_ARGSCAT);
+                COUNT_NODE(NODE_ARGSPUSH);
+                COUNT_NODE(NODE_SPLAT);
+                COUNT_NODE(NODE_BLOCK_PASS);
+                COUNT_NODE(NODE_DEFN);
+                COUNT_NODE(NODE_DEFS);
+                COUNT_NODE(NODE_ALIAS);
+                COUNT_NODE(NODE_VALIAS);
+                COUNT_NODE(NODE_UNDEF);
+                COUNT_NODE(NODE_CLASS);
+                COUNT_NODE(NODE_MODULE);
+                COUNT_NODE(NODE_SCLASS);
+                COUNT_NODE(NODE_COLON2);
+                COUNT_NODE(NODE_COLON3);
+                COUNT_NODE(NODE_DOT2);
+                COUNT_NODE(NODE_DOT3);
+                COUNT_NODE(NODE_FLIP2);
+                COUNT_NODE(NODE_FLIP3);
+                COUNT_NODE(NODE_SELF);
+                COUNT_NODE(NODE_NIL);
+                COUNT_NODE(NODE_TRUE);
+                COUNT_NODE(NODE_FALSE);
+                COUNT_NODE(NODE_ERRINFO);
+                COUNT_NODE(NODE_DEFINED);
+                COUNT_NODE(NODE_POSTEXE);
+                COUNT_NODE(NODE_DSYM);
+                COUNT_NODE(NODE_ATTRASGN);
+                COUNT_NODE(NODE_LAMBDA);
+                COUNT_NODE(NODE_ARYPTN);
+                COUNT_NODE(NODE_FNDPTN);
+                COUNT_NODE(NODE_HSHPTN);
+                COUNT_NODE(NODE_ERROR);
 #undef COUNT_NODE
-	      case NODE_LAST: break;
-	    }
-	    UNREACHABLE;
-	  set:
-	    rb_hash_aset(hash, node, SIZET2NUM(nodes[i]));
-	}
+              case NODE_LAST: break;
+            }
+            UNREACHABLE;
+          set:
+            rb_hash_aset(hash, node, SIZET2NUM(nodes[i]));
+        }
     }
     return hash;
 }
@@ -629,20 +630,22 @@ count_imemo_objects(int argc, VALUE *argv, VALUE self)
     VALUE hash = setup_hash(argc, argv);
 
     if (imemo_type_ids[0] == 0) {
-        imemo_type_ids[0] = rb_intern("imemo_env");
-	imemo_type_ids[1] = rb_intern("imemo_cref");
-	imemo_type_ids[2] = rb_intern("imemo_svar");
-	imemo_type_ids[3] = rb_intern("imemo_throw_data");
-	imemo_type_ids[4] = rb_intern("imemo_ifunc");
-	imemo_type_ids[5] = rb_intern("imemo_memo");
-	imemo_type_ids[6] = rb_intern("imemo_ment");
-	imemo_type_ids[7] = rb_intern("imemo_iseq");
-	imemo_type_ids[8] = rb_intern("imemo_tmpbuf");
-        imemo_type_ids[9] = rb_intern("imemo_ast");
-        imemo_type_ids[10] = rb_intern("imemo_parser_strterm");
-        imemo_type_ids[11] = rb_intern("imemo_callinfo");
-        imemo_type_ids[12] = rb_intern("imemo_callcache");
-        imemo_type_ids[13] = rb_intern("imemo_constcache");
+#define INIT_IMEMO_TYPE_ID(n) (imemo_type_ids[n] = rb_intern_const(#n))
+        INIT_IMEMO_TYPE_ID(imemo_env);
+        INIT_IMEMO_TYPE_ID(imemo_cref);
+        INIT_IMEMO_TYPE_ID(imemo_svar);
+        INIT_IMEMO_TYPE_ID(imemo_throw_data);
+        INIT_IMEMO_TYPE_ID(imemo_ifunc);
+        INIT_IMEMO_TYPE_ID(imemo_memo);
+        INIT_IMEMO_TYPE_ID(imemo_ment);
+        INIT_IMEMO_TYPE_ID(imemo_iseq);
+        INIT_IMEMO_TYPE_ID(imemo_tmpbuf);
+        INIT_IMEMO_TYPE_ID(imemo_ast);
+        INIT_IMEMO_TYPE_ID(imemo_parser_strterm);
+        INIT_IMEMO_TYPE_ID(imemo_callinfo);
+        INIT_IMEMO_TYPE_ID(imemo_callcache);
+        INIT_IMEMO_TYPE_ID(imemo_constcache);
+#undef INIT_IMEMO_TYPE_ID
     }
 
     each_object_with_flags(count_imemo_objects_i, (void *)hash);
@@ -815,26 +818,26 @@ reachable_object_from_root_i(const char *category, VALUE obj, void *ptr)
     VALUE category_objects;
 
     if (category == data->last_category) {
-	category_str = data->last_category_str;
-	category_objects = data->last_category_objects;
+        category_str = data->last_category_str;
+        category_objects = data->last_category_objects;
     }
     else {
-	data->last_category = category;
-	category_str = data->last_category_str = rb_str_new2(category);
-	category_objects = data->last_category_objects = rb_ident_hash_new();
-	if (!NIL_P(rb_hash_lookup(data->categories, category_str))) {
-	    rb_bug("reachable_object_from_root_i: category should insert at once");
-	}
-	rb_hash_aset(data->categories, category_str, category_objects);
+        data->last_category = category;
+        category_str = data->last_category_str = rb_str_new2(category);
+        category_objects = data->last_category_objects = rb_ident_hash_new();
+        if (!NIL_P(rb_hash_lookup(data->categories, category_str))) {
+            rb_bug("reachable_object_from_root_i: category should insert at once");
+        }
+        rb_hash_aset(data->categories, category_str, category_objects);
     }
 
     if (rb_objspace_markable_object_p(obj) &&
-	obj != data->categories &&
-	obj != data->last_category_objects) {
-	if (rb_objspace_internal_object_p(obj)) {
-	    obj = iow_newobj(obj);
-	}
-	rb_hash_aset(category_objects, obj, obj);
+        obj != data->categories &&
+        obj != data->last_category_objects) {
+        if (rb_objspace_internal_object_p(obj)) {
+            obj = iow_newobj(obj);
+        }
+        rb_hash_aset(category_objects, obj, obj);
     }
 }
 
@@ -870,14 +873,14 @@ static VALUE
 wrap_klass_iow(VALUE klass)
 {
     if (!RTEST(klass)) {
-	return Qnil;
+        return Qnil;
     }
     else if (RB_TYPE_P(klass, T_ICLASS) ||
              CLASS_OF(klass) == Qfalse /* hidden object */) {
-	return iow_newobj(klass);
+        return iow_newobj(klass);
     }
     else {
-	return klass;
+        return klass;
     }
 }
 
@@ -896,7 +899,7 @@ objspace_internal_class_of(VALUE self, VALUE obj)
     VALUE klass;
 
     if (rb_typeddata_is_kind_of(obj, &iow_data_type)) {
-	obj = (VALUE)DATA_PTR(obj);
+        obj = (VALUE)DATA_PTR(obj);
     }
 
     if (RB_TYPE_P(obj, T_IMEMO)) {
@@ -923,17 +926,17 @@ objspace_internal_super_of(VALUE self, VALUE obj)
     VALUE super;
 
     if (rb_typeddata_is_kind_of(obj, &iow_data_type)) {
-	obj = (VALUE)DATA_PTR(obj);
+        obj = (VALUE)DATA_PTR(obj);
     }
 
     switch (OBJ_BUILTIN_TYPE(obj)) {
       case T_MODULE:
       case T_CLASS:
       case T_ICLASS:
-	super = RCLASS_SUPER(obj);
-	break;
+        super = RCLASS_SUPER(obj);
+        break;
       default:
-	rb_raise(rb_eArgError, "class or module is expected");
+        rb_raise(rb_eArgError, "class or module is expected");
     }
 
     return wrap_klass_iow(super);
diff --git a/ext/objspace/objspace_dump.c b/ext/objspace/objspace_dump.c
index b570acbd95..c3cc9a1e7b 100644
--- a/ext/objspace/objspace_dump.c
+++ b/ext/objspace/objspace_dump.c
@@ -13,10 +13,15 @@
 **********************************************************************/
 
 #include "gc.h"
+#include "id_table.h"
 #include "internal.h"
+#include "internal/array.h"
+#include "internal/class.h"
 #include "internal/hash.h"
 #include "internal/string.h"
 #include "internal/sanitizers.h"
+#include "symbol.h"
+#include "shape.h"
 #include "node.h"
 #include "objspace.h"
 #include "ruby/debug.h"
@@ -41,6 +46,7 @@ struct dump_config {
     unsigned int full_heap: 1;
     unsigned int partial_dump;
     size_t since;
+    size_t shapes_since;
     unsigned long buffer_len;
     char buffer[BUFFER_CAPACITY];
 };
@@ -76,7 +82,8 @@ buffer_ensure_capa(struct dump_config *dc, unsigned long requested)
     }
 }
 
-static void buffer_append(struct dump_config *dc, const char *cstr, unsigned long len)
+static void
+buffer_append(struct dump_config *dc, const char *cstr, unsigned long len)
 {
     if (LIKELY(len > 0)) {
         buffer_ensure_capa(dc, len);
@@ -142,10 +149,10 @@ dump_append_sizet(struct dump_config *dc, const size_t number)
 }
 
 static void
-dump_append_c(struct dump_config *dc, char c)
+dump_append_c(struct dump_config *dc, unsigned char c)
 {
     if (c <= 0x1f) {
-        const unsigned int width = (sizeof(c) * CHAR_BIT / 4) + 5;
+        const unsigned int width = rb_strlen_lit("\\u0000") + 1;
         buffer_ensure_capa(dc, width);
         unsigned long required = snprintf(dc->buffer + dc->buffer_len, width, "\\u00%02x", c);
         RUBY_ASSERT(required <= width);
@@ -163,7 +170,7 @@ dump_append_ref(struct dump_config *dc, VALUE ref)
 {
     RUBY_ASSERT(ref > 0);
 
-    char buffer[((sizeof(VALUE) * CHAR_BIT + 3) / 4) + 4];
+    char buffer[roomof(sizeof(VALUE) * CHAR_BIT, 4) + rb_strlen_lit("\"0x\"")];
     char *buffer_start, *buffer_end;
 
     buffer_start = buffer_end = &buffer[sizeof(buffer)];
@@ -235,32 +242,32 @@ obj_type(VALUE obj)
 {
     switch (BUILTIN_TYPE(obj)) {
 #define CASE_TYPE(type) case T_##type: return #type
-	CASE_TYPE(NONE);
-	CASE_TYPE(NIL);
-	CASE_TYPE(OBJECT);
-	CASE_TYPE(CLASS);
-	CASE_TYPE(ICLASS);
-	CASE_TYPE(MODULE);
-	CASE_TYPE(FLOAT);
-	CASE_TYPE(STRING);
-	CASE_TYPE(REGEXP);
-	CASE_TYPE(ARRAY);
-	CASE_TYPE(HASH);
-	CASE_TYPE(STRUCT);
-	CASE_TYPE(BIGNUM);
-	CASE_TYPE(FILE);
-	CASE_TYPE(FIXNUM);
-	CASE_TYPE(TRUE);
-	CASE_TYPE(FALSE);
-	CASE_TYPE(DATA);
-	CASE_TYPE(MATCH);
-	CASE_TYPE(SYMBOL);
-	CASE_TYPE(RATIONAL);
-	CASE_TYPE(COMPLEX);
-	CASE_TYPE(IMEMO);
-	CASE_TYPE(UNDEF);
-	CASE_TYPE(NODE);
-	CASE_TYPE(ZOMBIE);
+        CASE_TYPE(NONE);
+        CASE_TYPE(NIL);
+        CASE_TYPE(OBJECT);
+        CASE_TYPE(CLASS);
+        CASE_TYPE(ICLASS);
+        CASE_TYPE(MODULE);
+        CASE_TYPE(FLOAT);
+        CASE_TYPE(STRING);
+        CASE_TYPE(REGEXP);
+        CASE_TYPE(ARRAY);
+        CASE_TYPE(HASH);
+        CASE_TYPE(STRUCT);
+        CASE_TYPE(BIGNUM);
+        CASE_TYPE(FILE);
+        CASE_TYPE(FIXNUM);
+        CASE_TYPE(TRUE);
+        CASE_TYPE(FALSE);
+        CASE_TYPE(DATA);
+        CASE_TYPE(MATCH);
+        CASE_TYPE(SYMBOL);
+        CASE_TYPE(RATIONAL);
+        CASE_TYPE(COMPLEX);
+        CASE_TYPE(IMEMO);
+        CASE_TYPE(UNDEF);
+        CASE_TYPE(NODE);
+        CASE_TYPE(ZOMBIE);
 #undef CASE_TYPE
       default: break;
     }
@@ -313,6 +320,17 @@ reachable_object_i(VALUE ref, void *data)
     dc->cur_obj_references++;
 }
 
+static bool
+dump_string_ascii_only(const char *str, long size)
+{
+    for (long i = 0; i < size; i++) {
+        if (str[i] & 0x80) {
+            return false;
+        }
+    }
+    return true;
+}
+
 static void
 dump_append_string_content(struct dump_config *dc, VALUE obj)
 {
@@ -323,12 +341,34 @@ dump_append_string_content(struct dump_config *dc, VALUE obj)
         dump_append_sizet(dc, rb_str_capacity(obj));
     }
 
-    if (is_ascii_string(obj)) {
-        dump_append(dc, ", \"value\":");
-        dump_append_string_value(dc, obj);
+    if (RSTRING_LEN(obj) && rb_enc_asciicompat(rb_enc_from_index(ENCODING_GET(obj)))) {
+        int cr = ENC_CODERANGE(obj);
+        if (cr == RUBY_ENC_CODERANGE_UNKNOWN) {
+            if (dump_string_ascii_only(RSTRING_PTR(obj), RSTRING_LEN(obj))) {
+                cr = RUBY_ENC_CODERANGE_7BIT;
+            }
+        }
+        if (cr == RUBY_ENC_CODERANGE_7BIT) {
+            dump_append(dc, ", \"value\":");
+            dump_append_string_value(dc, obj);
+        }
+    }
+}
+
+static inline void
+dump_append_id(struct dump_config *dc, ID id)
+{
+    if (is_instance_id(id)) {
+        dump_append_string_value(dc, rb_sym2str(ID2SYM(id)));
+    }
+    else {
+        dump_append(dc, "\"ID_INTERNAL(");
+        dump_append_sizet(dc, rb_id_to_serial(id));
+        dump_append(dc, ")\"");
     }
 }
 
+
 static void
 dump_object(VALUE obj, struct dump_config *dc)
 {
@@ -345,7 +385,11 @@ dump_object(VALUE obj, struct dump_config *dc)
 
     dc->cur_obj = obj;
     dc->cur_obj_references = 0;
-    dc->cur_obj_klass = BUILTIN_TYPE(obj) == T_NODE ? 0 : RBASIC_CLASS(obj);
+    if (BUILTIN_TYPE(obj) == T_NODE || BUILTIN_TYPE(obj) == T_IMEMO) {
+        dc->cur_obj_klass = 0;
+    } else {
+        dc->cur_obj_klass = RBASIC_CLASS(obj);
+    }
 
     if (dc->partial_dump && (!ainfo || ainfo->generation < dc->since)) {
         return;
@@ -361,6 +405,10 @@ dump_object(VALUE obj, struct dump_config *dc)
     dump_append(dc, obj_type(obj));
     dump_append(dc, "\"");
 
+    size_t shape_id = rb_shape_get_shape_id(obj);
+    dump_append(dc, ", \"shape_id\":");
+    dump_append_sizet(dc, shape_id);
+
     dump_append(dc, ", \"slot_size\":");
     dump_append_sizet(dc, dc->cur_page_slot_size);
 
@@ -389,8 +437,6 @@ dump_object(VALUE obj, struct dump_config *dc)
       case T_STRING:
         if (STR_EMBED_P(obj))
             dump_append(dc, ", \"embedded\":true");
-        if (is_broken_string(obj))
-            dump_append(dc, ", \"broken\":true");
         if (FL_TEST(obj, RSTRING_FSTR))
             dump_append(dc, ", \"fstring\":true");
         if (STR_SHARED_P(obj))
@@ -403,6 +449,27 @@ dump_object(VALUE obj, struct dump_config *dc)
             dump_append(dc, rb_enc_name(rb_enc_from_index(ENCODING_GET(obj))));
             dump_append(dc, "\"");
         }
+
+        dump_append(dc, ", \"coderange\":\"");
+        switch (RB_ENC_CODERANGE(obj)) {
+          case RUBY_ENC_CODERANGE_UNKNOWN:
+            dump_append(dc, "unknown");
+            break;
+          case RUBY_ENC_CODERANGE_7BIT:
+            dump_append(dc, "7bit");
+            break;
+          case RUBY_ENC_CODERANGE_VALID:
+            dump_append(dc, "valid");
+            break;
+          case RUBY_ENC_CODERANGE_BROKEN:
+            dump_append(dc, "broken");
+            break;
+        }
+        dump_append(dc, "\"");
+
+        if (RB_ENC_CODERANGE(obj) == RUBY_ENC_CODERANGE_BROKEN)
+            dump_append(dc, ", \"broken\":true");
+
         break;
 
       case T_HASH:
@@ -417,7 +484,7 @@ dump_object(VALUE obj, struct dump_config *dc)
       case T_ARRAY:
         dump_append(dc, ", \"length\":");
         dump_append_ld(dc, RARRAY_LEN(obj));
-        if (RARRAY_LEN(obj) > 0 && FL_TEST(obj, ELTS_SHARED))
+        if (RARRAY_LEN(obj) > 0 && FL_TEST(obj, RARRAY_SHARED_FLAG))
             dump_append(dc, ", \"shared\":true");
         if (FL_TEST(obj, RARRAY_EMBED_FLAG))
             dump_append(dc, ", \"embedded\":true");
@@ -431,6 +498,9 @@ dump_object(VALUE obj, struct dump_config *dc)
         break;
 
       case T_CLASS:
+        dump_append(dc, ", \"variation_count\":");
+        dump_append_d(dc, RCLASS_EXT(obj)->variation_count);
+
       case T_MODULE:
         if (rb_class_get_superclass(obj)) {
             dump_append(dc, ", \"superclass\":");
@@ -443,7 +513,8 @@ dump_object(VALUE obj, struct dump_config *dc)
                 dump_append(dc, ", \"name\":\"");
                 dump_append(dc, RSTRING_PTR(mod_name));
                 dump_append(dc, "\"");
-            } else {
+            }
+            else {
                 VALUE real_mod_name = rb_mod_name(rb_class_real(obj));
                 if (RTEST(real_mod_name)) {
                     dump_append(dc, ", \"real_class_name\":\"");
@@ -474,7 +545,10 @@ dump_object(VALUE obj, struct dump_config *dc)
 
       case T_OBJECT:
         dump_append(dc, ", \"ivars\":");
-        dump_append_lu(dc, ROBJECT_NUMIV(obj));
+        dump_append_lu(dc, ROBJECT_IV_COUNT(obj));
+        if (rb_shape_obj_too_complex(obj)) {
+            dump_append(dc, ", \"too_complex_shape\":true");
+        }
         break;
 
       case T_FILE:
@@ -486,8 +560,8 @@ dump_object(VALUE obj, struct dump_config *dc)
         break;
 
       case T_ZOMBIE:
-          dump_append(dc, "}\n");
-          return;
+        dump_append(dc, "}\n");
+        return;
 
       default:
         break;
@@ -545,8 +619,8 @@ heap_i(void *vstart, void *vend, size_t stride, void *data)
         asan_unpoison_object(v, false);
         dc->cur_page_slot_size = stride;
 
-	if (dc->full_heap || RBASIC(v)->flags)
-	    dump_object(v, dc);
+        if (dc->full_heap || RBASIC(v)->flags)
+            dump_object(v, dc);
 
         if (ptr) {
             asan_poison_object(v);
@@ -578,7 +652,7 @@ root_obj_i(const char *category, VALUE obj, void *data)
 }
 
 static void
-dump_output(struct dump_config *dc, VALUE output, VALUE full, VALUE since)
+dump_output(struct dump_config *dc, VALUE output, VALUE full, VALUE since, VALUE shapes)
 {
 
     dc->full_heap = 0;
@@ -587,7 +661,8 @@ dump_output(struct dump_config *dc, VALUE output, VALUE full, VALUE since)
     if (TYPE(output) == T_STRING) {
         dc->stream = Qfalse;
         dc->string = output;
-    } else {
+    }
+    else {
         dc->stream = output;
         dc->string = Qfalse;
     }
@@ -599,9 +674,12 @@ dump_output(struct dump_config *dc, VALUE output, VALUE full, VALUE since)
     if (RTEST(since)) {
         dc->partial_dump = 1;
         dc->since = NUM2SIZET(since);
-    } else {
+    }
+    else {
         dc->partial_dump = 0;
     }
+
+    dc->shapes_since = RTEST(shapes) ? NUM2SIZET(shapes) : 0;
 }
 
 static VALUE
@@ -611,12 +689,14 @@ dump_result(struct dump_config *dc)
 
     if (dc->string) {
         return dc->string;
-    } else {
+    }
+    else {
         rb_io_flush(dc->stream);
         return dc->stream;
     }
 }
 
+/* :nodoc: */
 static VALUE
 objspace_dump(VALUE os, VALUE obj, VALUE output)
 {
@@ -625,18 +705,87 @@ objspace_dump(VALUE os, VALUE obj, VALUE output)
         dc.cur_page_slot_size = rb_gc_obj_slot_size(obj);
     }
 
-    dump_output(&dc, output, Qnil, Qnil);
+    dump_output(&dc, output, Qnil, Qnil, Qnil);
 
     dump_object(obj, &dc);
 
     return dump_result(&dc);
 }
 
+static void
+shape_i(rb_shape_t *shape, void *data)
+{
+    struct dump_config *dc = (struct dump_config *)data;
+
+    size_t shape_id = rb_shape_id(shape);
+    if (shape_id < dc->shapes_since) {
+        return;
+    }
+
+    dump_append(dc, "{\"address\":");
+    dump_append_ref(dc, (VALUE)shape);
+
+    dump_append(dc, ", \"type\":\"SHAPE\", \"id\":");
+    dump_append_sizet(dc, shape_id);
+
+    if (shape->type != SHAPE_ROOT) {
+        dump_append(dc, ", \"parent_id\":");
+        dump_append_lu(dc, shape->parent_id);
+    }
+
+    dump_append(dc, ", \"depth\":");
+    dump_append_sizet(dc, rb_shape_depth(shape));
+
+    dump_append(dc, ", \"shape_type\":");
+    switch((enum shape_type)shape->type) {
+      case SHAPE_ROOT:
+        dump_append(dc, "\"ROOT\"");
+        break;
+      case SHAPE_IVAR:
+        dump_append(dc, "\"IVAR\"");
+
+        dump_append(dc, ",\"edge_name\":");
+        dump_append_id(dc, shape->edge_name);
+
+        break;
+      case SHAPE_FROZEN:
+        dump_append(dc, "\"FROZEN\"");
+        break;
+      case SHAPE_CAPACITY_CHANGE:
+        dump_append(dc, "\"CAPACITY_CHANGE\"");
+        dump_append(dc, ", \"capacity\":");
+        dump_append_sizet(dc, shape->capacity);
+        break;
+      case SHAPE_INITIAL_CAPACITY:
+        dump_append(dc, "\"INITIAL_CAPACITY\"");
+        dump_append(dc, ", \"capacity\":");
+        dump_append_sizet(dc, shape->capacity);
+        break;
+      case SHAPE_T_OBJECT:
+        dump_append(dc, "\"T_OBJECT\"");
+        break;
+      case SHAPE_OBJ_TOO_COMPLEX:
+        dump_append(dc, "\"OBJ_TOO_COMPLEX\"");
+        break;
+      default:
+        rb_bug("[objspace] unexpected shape type");
+    }
+
+    dump_append(dc, ", \"edges\":");
+    dump_append_sizet(dc, rb_shape_edges_count(shape));
+
+    dump_append(dc, ", \"memsize\":");
+    dump_append_sizet(dc, rb_shape_memsize(shape));
+
+    dump_append(dc, "}\n");
+}
+
+/* :nodoc: */
 static VALUE
-objspace_dump_all(VALUE os, VALUE output, VALUE full, VALUE since)
+objspace_dump_all(VALUE os, VALUE output, VALUE full, VALUE since, VALUE shapes)
 {
     struct dump_config dc = {0,};
-    dump_output(&dc, output, full, since);
+    dump_output(&dc, output, full, since, shapes);
 
     if (!dc.partial_dump || dc.since == 0) {
         /* dump roots */
@@ -644,12 +793,29 @@ objspace_dump_all(VALUE os, VALUE output, VALUE full, VALUE since)
         if (dc.roots) dump_append(&dc, "]}\n");
     }
 
+    if (RTEST(shapes)) {
+        rb_shape_each_shape(shape_i, &dc);
+    }
+
     /* dump all objects */
     rb_objspace_each_objects(heap_i, &dc);
 
     return dump_result(&dc);
 }
 
+/* :nodoc: */
+static VALUE
+objspace_dump_shapes(VALUE os, VALUE output, VALUE shapes)
+{
+    struct dump_config dc = {0,};
+    dump_output(&dc, output, Qfalse, Qnil, shapes);
+
+    if (RTEST(shapes)) {
+        rb_shape_each_shape(shape_i, &dc);
+    }
+    return dump_result(&dc);
+}
+
 void
 Init_objspace_dump(VALUE rb_mObjSpace)
 {
@@ -659,7 +825,8 @@ Init_objspace_dump(VALUE rb_mObjSpace)
 #endif
 
     rb_define_module_function(rb_mObjSpace, "_dump", objspace_dump, 2);
-    rb_define_module_function(rb_mObjSpace, "_dump_all", objspace_dump_all, 3);
+    rb_define_module_function(rb_mObjSpace, "_dump_all", objspace_dump_all, 4);
+    rb_define_module_function(rb_mObjSpace, "_dump_shapes", objspace_dump_shapes, 2);
 
     /* force create static IDs */
     rb_obj_gc_flags(rb_mObjSpace, 0, 0);
diff --git a/ext/openssl/History.md b/ext/openssl/History.md
index 479ec3b4a2..1e0df7dd87 100644
--- a/ext/openssl/History.md
+++ b/ext/openssl/History.md
@@ -1,3 +1,77 @@
+Version 3.1.0
+=============
+
+Ruby/OpenSSL 3.1 will be maintained for the lifetime of Ruby 3.2.
+
+Merged bug fixes in 2.2.3 and 3.0.2. Among the new features and changes are:
+
+Notable changes
+---------------
+
+* Add `OpenSSL::SSL::SSLContext#ciphersuites=` to allow setting TLS 1.3 cipher
+  suites.
+  [[GitHub #493]](https://github.com/ruby/openssl/pull/493)
+* Add `OpenSSL::SSL::SSLSocket#export_keying_material` for exporting keying
+  material of the session, as defined in RFC 5705.
+  [[GitHub #530]](https://github.com/ruby/openssl/pull/530)
+* Add `OpenSSL::SSL::SSLContext#keylog_cb=` for setting the TLS key logging
+  callback, which is useful for supporting NSS's SSLKEYLOGFILE debugging output.
+  [[GitHub #536]](https://github.com/ruby/openssl/pull/536)
+* Remove the default digest algorithm from `OpenSSL::OCSP::BasicResponse#sign`
+  and `OpenSSL::OCSP::Request#sign`. Omitting the 5th parameter of these
+  methods used to be equivalent of specifying SHA-1. This default value is now
+  removed and we will let the underlying OpenSSL library decide instead.
+  [[GitHub #507]](https://github.com/ruby/openssl/pull/507)
+* Add `OpenSSL::BN#mod_sqrt`.
+  [[GitHub #553]](https://github.com/ruby/openssl/pull/553)
+* Allow calling `OpenSSL::Cipher#update` with an empty string. This was
+  prohibited to workaround an ancient bug in OpenSSL.
+  [[GitHub #568]](https://github.com/ruby/openssl/pull/568)
+* Fix build on platforms without socket support, such as WASI. `OpenSSL::SSL`
+  will not be defined if OpenSSL is compiled with `OPENSSL_NO_SOCK`.
+  [[GitHub #558]](https://github.com/ruby/openssl/pull/558)
+* Improve support for recent LibreSSL versions. This includes HKDF support in
+  LibreSSL 3.6 and Ed25519 support in LibreSSL 3.7.
+
+
+Version 3.0.2
+=============
+
+Merged changes in 2.2.3. Additionally, the following issues are fixed by this
+release.
+
+Bug fixes
+---------
+
+* Fix OpenSSL::PKey::EC#check_key not working correctly on OpenSSL 3.0.
+  [[GitHub #563]](https://github.com/ruby/openssl/issues/563)
+  [[GitHub #580]](https://github.com/ruby/openssl/pull/580)
+
+
+Version 3.0.1
+=============
+
+Merged changes in 2.1.4 and 2.2.2. Additionally, the following issues are fixed
+by this release.
+
+Bug fixes
+---------
+
+* Add missing type check in OpenSSL::PKey::PKey#sign's optional parameters.
+  [[GitHub #531]](https://github.com/ruby/openssl/pull/531)
+* Work around OpenSSL 3.0's HMAC issues with a zero-length key.
+  [[GitHub #538]](https://github.com/ruby/openssl/pull/538)
+* Fix a regression in OpenSSL::PKey::DSA.generate's default of 'q' size.
+  [[GitHub #483]](https://github.com/ruby/openssl/issues/483)
+  [[GitHub #539]](https://github.com/ruby/openssl/pull/539)
+* Restore OpenSSL::PKey.read's ability to decode "openssl ecparam -genkey"
+  output when linked against OpenSSL 3.0.
+  [[GitHub #535]](https://github.com/ruby/openssl/pull/535)
+  [[GitHub #540]](https://github.com/ruby/openssl/pull/540)
+* Restore error checks in OpenSSL::PKey::EC#{to_der,to_pem}.
+  [[GitHub #541]](https://github.com/ruby/openssl/pull/541)
+
+
 Version 3.0.0
 =============
 
@@ -100,6 +174,27 @@ Notable changes
     [[GitHub #342]](https://github.com/ruby/openssl/issues/342)
 
 
+Version 2.2.3
+=============
+
+Bug fixes
+---------
+
+* Fix serveral methods in OpenSSL::PKey::EC::Point attempting to raise an error
+  with an incorrect class, which would end up with a TypeError.
+  [[GitHub #570]](https://github.com/ruby/openssl/pull/570)
+* Fix OpenSSL::PKey::EC::Point#eql? and OpenSSL::PKey::EC::Group#eql?
+  incorrectly treated OpenSSL's internal errors as "not equal".
+  [[GitHub #564]](https://github.com/ruby/openssl/pull/564)
+* Fix build with LibreSSL 3.5 or later.
+
+
+Version 2.2.2
+=============
+
+Merged changes in 2.1.4.
+
+
 Version 2.2.1
 =============
 
@@ -194,6 +289,16 @@ Notable changes
   [[GitHub #297]](https://github.com/ruby/openssl/pull/297)
 
 
+Version 2.1.4
+=============
+
+Bug fixes
+---------
+
+* Do not use pkg-config if --with-openssl-dir option is specified.
+ [[GitHub #486]](https://github.com/ruby/openssl/pull/486)
+
+
 Version 2.1.3
 =============
 
diff --git a/ext/openssl/extconf.rb b/ext/openssl/extconf.rb
index 467f7e7a86..bc3e4d3a21 100644
--- a/ext/openssl/extconf.rb
+++ b/ext/openssl/extconf.rb
@@ -13,7 +13,7 @@
 
 require "mkmf"
 
-dir_config("openssl")
+dir_config_given = dir_config("openssl").any?
 dir_config("kerberos")
 
 Logging::message "=== OpenSSL for Ruby configurator ===\n"
@@ -25,8 +25,9 @@ Logging::message "=== OpenSSL for Ruby configurator ===\n"
 if with_config("debug") or enable_config("debug")
   $defs.push("-DOSSL_DEBUG")
 end
+$defs.push("-D""OPENSSL_SUPPRESS_DEPRECATED")
 
-have_func("rb_io_maybe_wait") # Ruby 3.1
+have_func("rb_io_maybe_wait(0, Qnil, Qnil, Qnil)", "ruby/io.h") # Ruby 3.1
 
 Logging::message "=== Checking for system dependent stuff... ===\n"
 have_library("nsl", "t_open")
@@ -92,7 +93,7 @@ def find_openssl_library
 end
 
 Logging::message "=== Checking for required stuff... ===\n"
-pkg_config_found = pkg_config("openssl") && have_header("openssl/ssl.h")
+pkg_config_found = !dir_config_given && pkg_config("openssl") && have_header("openssl/ssl.h")
 
 if !pkg_config_found && !find_openssl_library
   Logging::message "=== Checking for required stuff failed. ===\n"
@@ -120,8 +121,13 @@ if is_libressl && ($mswin || $mingw)
 end
 
 Logging::message "=== Checking for OpenSSL features... ===\n"
+evp_h = "openssl/evp.h".freeze
+x509_h = "openssl/x509.h".freeze
+ts_h = "openssl/ts.h".freeze
+ssl_h = "openssl/ssl.h".freeze
+
 # compile options
-have_func("RAND_egd")
+have_func("RAND_egd()", "openssl/rand.h")
 engines = %w{dynamic 4758cca aep atalla chil
              cswift nuron sureware ubsec padlock capi gmp gost cryptodev}
 engines.each { |name|
@@ -132,64 +138,59 @@ engines.each { |name|
 if !have_struct_member("SSL", "ctx", "openssl/ssl.h") || is_libressl
   $defs.push("-DHAVE_OPAQUE_OPENSSL")
 end
-have_func("EVP_MD_CTX_new")
-have_func("EVP_MD_CTX_free")
-have_func("EVP_MD_CTX_pkey_ctx")
-have_func("X509_STORE_get_ex_data")
-have_func("X509_STORE_set_ex_data")
-have_func("X509_STORE_get_ex_new_index")
-have_func("X509_CRL_get0_signature")
-have_func("X509_REQ_get0_signature")
-have_func("X509_REVOKED_get0_serialNumber")
-have_func("X509_REVOKED_get0_revocationDate")
-have_func("X509_get0_tbs_sigalg")
-have_func("X509_STORE_CTX_get0_untrusted")
-have_func("X509_STORE_CTX_get0_cert")
-have_func("X509_STORE_CTX_get0_chain")
-have_func("OCSP_SINGLERESP_get0_id")
-have_func("SSL_CTX_get_ciphers")
-have_func("X509_up_ref")
-have_func("X509_CRL_up_ref")
-have_func("X509_STORE_up_ref")
-have_func("SSL_SESSION_up_ref")
-have_func("EVP_PKEY_up_ref")
-have_func("SSL_CTX_set_min_proto_version(NULL, 0)", "openssl/ssl.h")
-have_func("SSL_CTX_get_security_level")
-have_func("X509_get0_notBefore")
-have_func("SSL_SESSION_get_protocol_version")
-have_func("TS_STATUS_INFO_get0_status")
-have_func("TS_STATUS_INFO_get0_text")
-have_func("TS_STATUS_INFO_get0_failure_info")
-have_func("TS_VERIFY_CTS_set_certs(NULL, NULL)", "openssl/ts.h")
-have_func("TS_VERIFY_CTX_set_store")
-have_func("TS_VERIFY_CTX_add_flags")
-have_func("TS_RESP_CTX_set_time_cb")
-have_func("EVP_PBE_scrypt")
-have_func("SSL_CTX_set_post_handshake_auth")
+have_func("EVP_MD_CTX_new()", evp_h)
+have_func("EVP_MD_CTX_free(NULL)", evp_h)
+have_func("EVP_MD_CTX_pkey_ctx(NULL)", evp_h)
+have_func("X509_STORE_get_ex_data(NULL, 0)", x509_h)
+have_func("X509_STORE_set_ex_data(NULL, 0, NULL)", x509_h)
+have_func("X509_STORE_get_ex_new_index(0, NULL, NULL, NULL, NULL)", x509_h)
+have_func("X509_CRL_get0_signature(NULL, NULL, NULL)", x509_h)
+have_func("X509_REQ_get0_signature(NULL, NULL, NULL)", x509_h)
+have_func("X509_REVOKED_get0_serialNumber(NULL)", x509_h)
+have_func("X509_REVOKED_get0_revocationDate(NULL)", x509_h)
+have_func("X509_get0_tbs_sigalg(NULL)", x509_h)
+have_func("X509_STORE_CTX_get0_untrusted(NULL)", x509_h)
+have_func("X509_STORE_CTX_get0_cert(NULL)", x509_h)
+have_func("X509_STORE_CTX_get0_chain(NULL)", x509_h)
+have_func("OCSP_SINGLERESP_get0_id(NULL)", "openssl/ocsp.h")
+have_func("SSL_CTX_get_ciphers(NULL)", ssl_h)
+have_func("X509_up_ref(NULL)", x509_h)
+have_func("X509_CRL_up_ref(NULL)", x509_h)
+have_func("X509_STORE_up_ref(NULL)", x509_h)
+have_func("SSL_SESSION_up_ref(NULL)", ssl_h)
+have_func("EVP_PKEY_up_ref(NULL)", evp_h)
+have_func("SSL_CTX_set_min_proto_version(NULL, 0)", ssl_h)
+have_func("SSL_CTX_get_security_level(NULL)", ssl_h)
+have_func("X509_get0_notBefore(NULL)", x509_h)
+have_func("SSL_SESSION_get_protocol_version(NULL)", ssl_h)
+have_func("TS_STATUS_INFO_get0_status(NULL)", ts_h)
+have_func("TS_STATUS_INFO_get0_text(NULL)", ts_h)
+have_func("TS_STATUS_INFO_get0_failure_info(NULL)", ts_h)
+have_func("TS_VERIFY_CTS_set_certs(NULL, NULL)", ts_h)
+have_func("TS_VERIFY_CTX_set_store(NULL, NULL)", ts_h)
+have_func("TS_VERIFY_CTX_add_flags(NULL, 0)", ts_h)
+have_func("TS_RESP_CTX_set_time_cb(NULL, NULL, NULL)", ts_h)
+have_func("EVP_PBE_scrypt(\"\", 0, (unsigned char *)\"\", 0, 0, 0, 0, 0, NULL, 0)", evp_h)
+have_func("SSL_CTX_set_post_handshake_auth(NULL, 0)", ssl_h)
 
 # added in 1.1.1
-have_func("EVP_PKEY_check")
+have_func("EVP_PKEY_check(NULL)", evp_h)
+have_func("EVP_PKEY_new_raw_private_key(0, NULL, (unsigned char *)\"\", 0)", evp_h)
+have_func("SSL_CTX_set_ciphersuites(NULL, \"\")", ssl_h)
 
 # added in 3.0.0
-openssl_3 =
-have_func("SSL_set0_tmp_dh_pkey")
-have_func("ERR_get_error_all")
-have_func("TS_VERIFY_CTX_set_certs(NULL, NULL)", "openssl/ts.h")
-have_func("SSL_CTX_load_verify_file")
-have_func("BN_check_prime")
-have_func("EVP_MD_CTX_get0_md")
-have_func("EVP_MD_CTX_get_pkey_ctx")
-have_func("EVP_PKEY_eq")
-have_func("EVP_PKEY_dup")
+have_func("SSL_set0_tmp_dh_pkey(NULL, NULL)", ssl_h)
+have_func("ERR_get_error_all(NULL, NULL, NULL, NULL, NULL)", "openssl/err.h")
+have_func("TS_VERIFY_CTX_set_certs(NULL, NULL)", ts_h)
+have_func("SSL_CTX_load_verify_file(NULL, \"\")", ssl_h)
+have_func("BN_check_prime(NULL, NULL, NULL)", "openssl/bn.h")
+have_func("EVP_MD_CTX_get0_md(NULL)", evp_h)
+have_func("EVP_MD_CTX_get_pkey_ctx(NULL)", evp_h)
+have_func("EVP_PKEY_eq(NULL, NULL)", evp_h)
+have_func("EVP_PKEY_dup(NULL)", evp_h)
 
 Logging::message "=== Checking done. ===\n"
 
-if openssl_3
-  if $warnflags.sub!(/-W\K(?=deprecated-declarations)/, 'no-')
-    $warnflags << " -Wno-incompatible-pointer-types-discards-qualifiers"
-  end
-end
-
 create_header
 create_makefile("openssl")
 Logging::message "Done.\n"
diff --git a/ext/openssl/lib/openssl/pkey.rb b/ext/openssl/lib/openssl/pkey.rb
index c3e0629091..0414658a10 100644
--- a/ext/openssl/lib/openssl/pkey.rb
+++ b/ext/openssl/lib/openssl/pkey.rb
@@ -167,8 +167,16 @@ module OpenSSL::PKey
       # +size+::
       #   The desired key size in bits.
       def generate(size, &blk)
+        # FIPS 186-4 specifies four (L,N) pairs: (1024,160), (2048,224),
+        # (2048,256), and (3072,256).
+        #
+        # q size is derived here with compatibility with
+        # DSA_generator_parameters_ex() which previous versions of ruby/openssl
+        # used to call.
+        qsize = size >= 2048 ? 256 : 160
         dsaparams = OpenSSL::PKey.generate_parameters("DSA", {
           "dsa_paramgen_bits" => size,
+          "dsa_paramgen_q_bits" => qsize,
         }, &blk)
         OpenSSL::PKey.generate_key(dsaparams)
       end
@@ -355,7 +363,8 @@ module OpenSSL::PKey
     #    rsa.private_encrypt(string, padding) -> String
     #
     # Encrypt +string+ with the private key.  +padding+ defaults to
-    # PKCS1_PADDING. The encrypted string output can be decrypted using
+    # PKCS1_PADDING, which is known to be insecure but is kept for backwards
+    # compatibility. The encrypted string output can be decrypted using
     # #public_decrypt.
     #
     # <b>Deprecated in version 3.0</b>.
@@ -378,7 +387,8 @@ module OpenSSL::PKey
     #    rsa.public_decrypt(string, padding) -> String
     #
     # Decrypt +string+, which has been encrypted with the private key, with the
-    # public key.  +padding+ defaults to PKCS1_PADDING.
+    # public key.  +padding+ defaults to PKCS1_PADDING which is known to be
+    # insecure but is kept for backwards compatibility.
     #
     # <b>Deprecated in version 3.0</b>.
     # Consider using PKey::PKey#sign_raw and PKey::PKey#verify_raw, and
@@ -399,7 +409,8 @@ module OpenSSL::PKey
     #    rsa.public_encrypt(string, padding) -> String
     #
     # Encrypt +string+ with the public key.  +padding+ defaults to
-    # PKCS1_PADDING. The encrypted string output can be decrypted using
+    # PKCS1_PADDING, which is known to be insecure but is kept for backwards
+    # compatibility. The encrypted string output can be decrypted using
     # #private_decrypt.
     #
     # <b>Deprecated in version 3.0</b>.
@@ -420,7 +431,8 @@ module OpenSSL::PKey
     #    rsa.private_decrypt(string, padding) -> String
     #
     # Decrypt +string+, which has been encrypted with the public key, with the
-    # private key. +padding+ defaults to PKCS1_PADDING.
+    # private key. +padding+ defaults to PKCS1_PADDING, which is known to be
+    # insecure but is kept for backwards compatibility.
     #
     # <b>Deprecated in version 3.0</b>.
     # Consider using PKey::PKey#encrypt and PKey::PKey#decrypt instead.
diff --git a/ext/openssl/lib/openssl/ssl.rb b/ext/openssl/lib/openssl/ssl.rb
index a9103ecd27..ea8bb2a18e 100644
--- a/ext/openssl/lib/openssl/ssl.rb
+++ b/ext/openssl/lib/openssl/ssl.rb
@@ -11,6 +11,9 @@
 =end
 
 require "openssl/buffering"
+
+if defined?(OpenSSL::SSL)
+
 require "io/nonblock"
 require "ipaddr"
 require "socket"
@@ -540,3 +543,5 @@ YoaOffgTf5qxiwkjnlVZQc3whgnEt9FpVMvQ9eknyeGB5KHfayAc3+hUAvI3/Cr3
     end
   end
 end
+
+end
diff --git a/ext/openssl/lib/openssl/version.rb b/ext/openssl/lib/openssl/version.rb
index 5e60604353..4163f55064 100644
--- a/ext/openssl/lib/openssl/version.rb
+++ b/ext/openssl/lib/openssl/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module OpenSSL
-  VERSION = "3.0.0"
+  VERSION = "3.1.0"
 end
diff --git a/ext/openssl/openssl.gemspec b/ext/openssl/openssl.gemspec
index c6cd818336..8d83b69193 100644
--- a/ext/openssl/openssl.gemspec
+++ b/ext/openssl/openssl.gemspec
@@ -1,6 +1,6 @@
 Gem::Specification.new do |spec|
   spec.name          = "openssl"
-  spec.version       = "3.0.0"
+  spec.version       = "3.1.0"
   spec.authors       = ["Martin Bosslet", "SHIBATA Hiroshi", "Zachary Scott", "Kazuki Yamaguchi"]
   spec.email         = ["ruby-core@ruby-lang.org"]
   spec.summary       = %q{OpenSSL provides SSL, TLS and general purpose cryptography.}
diff --git a/ext/openssl/ossl.h b/ext/openssl/ossl.h
index 4b5126893b..facb80aa73 100644
--- a/ext/openssl/ossl.h
+++ b/ext/openssl/ossl.h
@@ -43,13 +43,19 @@
 #ifndef LIBRESSL_VERSION_NUMBER
 # define OSSL_IS_LIBRESSL 0
 # define OSSL_OPENSSL_PREREQ(maj, min, pat) \
-      (OPENSSL_VERSION_NUMBER >= (maj << 28) | (min << 20) | (pat << 12))
+      (OPENSSL_VERSION_NUMBER >= ((maj << 28) | (min << 20) | (pat << 12)))
 # define OSSL_LIBRESSL_PREREQ(maj, min, pat) 0
 #else
 # define OSSL_IS_LIBRESSL 1
 # define OSSL_OPENSSL_PREREQ(maj, min, pat) 0
 # define OSSL_LIBRESSL_PREREQ(maj, min, pat) \
-      (LIBRESSL_VERSION_NUMBER >= (maj << 28) | (min << 20) | (pat << 12))
+      (LIBRESSL_VERSION_NUMBER >= ((maj << 28) | (min << 20) | (pat << 12)))
+#endif
+
+#if OSSL_OPENSSL_PREREQ(3, 0, 0)
+# define OSSL_3_const const
+#else
+# define OSSL_3_const /* const */
 #endif
 
 #if !defined(OPENSSL_NO_ENGINE) && !OSSL_OPENSSL_PREREQ(3, 0, 0)
diff --git a/ext/openssl/ossl_asn1.c b/ext/openssl/ossl_asn1.c
index a61d3eefb1..71c452c88a 100644
--- a/ext/openssl/ossl_asn1.c
+++ b/ext/openssl/ossl_asn1.c
@@ -509,7 +509,8 @@ ossl_asn1_get_asn1type(VALUE obj)
     ASN1_TYPE *ret;
     VALUE value, rflag;
     void *ptr;
-    void (*free_func)();
+    typedef void free_func_type(void *);
+    free_func_type *free_func;
     int tag;
 
     tag = ossl_asn1_default_tag(obj);
@@ -522,16 +523,16 @@ ossl_asn1_get_asn1type(VALUE obj)
     case V_ASN1_INTEGER:         /* FALLTHROUGH */
     case V_ASN1_ENUMERATED:
 	ptr = obj_to_asn1int(value);
-	free_func = ASN1_INTEGER_free;
+	free_func = (free_func_type *)ASN1_INTEGER_free;
 	break;
     case V_ASN1_BIT_STRING:
         rflag = rb_attr_get(obj, sivUNUSED_BITS);
 	ptr = obj_to_asn1bstr(value, NUM2INT(rflag));
-	free_func = ASN1_BIT_STRING_free;
+	free_func = (free_func_type *)ASN1_BIT_STRING_free;
 	break;
     case V_ASN1_NULL:
 	ptr = obj_to_asn1null(value);
-	free_func = ASN1_NULL_free;
+	free_func = (free_func_type *)ASN1_NULL_free;
 	break;
     case V_ASN1_OCTET_STRING:    /* FALLTHROUGH */
     case V_ASN1_UTF8STRING:      /* FALLTHROUGH */
@@ -546,24 +547,24 @@ ossl_asn1_get_asn1type(VALUE obj)
     case V_ASN1_UNIVERSALSTRING: /* FALLTHROUGH */
     case V_ASN1_BMPSTRING:
 	ptr = obj_to_asn1str(value);
-	free_func = ASN1_STRING_free;
+	free_func = (free_func_type *)ASN1_STRING_free;
 	break;
     case V_ASN1_OBJECT:
 	ptr = obj_to_asn1obj(value);
-	free_func = ASN1_OBJECT_free;
+	free_func = (free_func_type *)ASN1_OBJECT_free;
 	break;
     case V_ASN1_UTCTIME:
 	ptr = obj_to_asn1utime(value);
-	free_func = ASN1_TIME_free;
+	free_func = (free_func_type *)ASN1_TIME_free;
 	break;
     case V_ASN1_GENERALIZEDTIME:
 	ptr = obj_to_asn1gtime(value);
-	free_func = ASN1_TIME_free;
+	free_func = (free_func_type *)ASN1_TIME_free;
 	break;
     case V_ASN1_SET:             /* FALLTHROUGH */
     case V_ASN1_SEQUENCE:
 	ptr = obj_to_asn1derstr(obj);
-	free_func = ASN1_STRING_free;
+	free_func = (free_func_type *)ASN1_STRING_free;
 	break;
     default:
 	ossl_raise(eASN1Error, "unsupported ASN.1 type");
@@ -1522,7 +1523,7 @@ Init_ossl_asn1(void)
      *
      * An Array that stores the name of a given tag number. These names are
      * the same as the name of the tag constant that is additionally defined,
-     * e.g. +UNIVERSAL_TAG_NAME[2] = "INTEGER"+ and +OpenSSL::ASN1::INTEGER = 2+.
+     * e.g. <tt>UNIVERSAL_TAG_NAME[2] = "INTEGER"</tt> and <tt>OpenSSL::ASN1::INTEGER = 2</tt>.
      *
      * == Example usage
      *
diff --git a/ext/openssl/ossl_bn.c b/ext/openssl/ossl_bn.c
index 56fa0ec302..bf2bac3679 100644
--- a/ext/openssl/ossl_bn.c
+++ b/ext/openssl/ossl_bn.c
@@ -577,22 +577,33 @@ BIGNUM_2c(gcd)
  */
 BIGNUM_2c(mod_sqr)
 
+#define BIGNUM_2cr(func)					\
+    static VALUE						\
+    ossl_bn_##func(VALUE self, VALUE other)			\
+    {								\
+	BIGNUM *bn1, *bn2 = GetBNPtr(other), *result;		\
+	VALUE obj;						\
+	GetBN(self, bn1);					\
+	obj = NewBN(rb_obj_class(self));			\
+	if (!(result = BN_##func(NULL, bn1, bn2, ossl_bn_ctx)))	\
+	    ossl_raise(eBNError, NULL);				\
+	SetBN(obj, result);					\
+	return obj;						\
+    }
+
 /*
+ * Document-method: OpenSSL::BN#mod_sqrt
+ * call-seq:
+ *   bn.mod_sqrt(bn2) => aBN
+ */
+BIGNUM_2cr(mod_sqrt)
+
+/*
+ * Document-method: OpenSSL::BN#mod_inverse
  * call-seq:
  *    bn.mod_inverse(bn2) => aBN
  */
-static VALUE
-ossl_bn_mod_inverse(VALUE self, VALUE other)
-{
-    BIGNUM *bn1, *bn2 = GetBNPtr(other), *result;
-    VALUE obj;
-    GetBN(self, bn1);
-    obj = NewBN(rb_obj_class(self));
-    if (!(result = BN_mod_inverse(NULL, bn1, bn2, ossl_bn_ctx)))
-        ossl_raise(eBNError, "BN_mod_inverse");
-    SetBN(obj, result);
-    return obj;
-}
+BIGNUM_2cr(mod_inverse)
 
 /*
  * call-seq:
@@ -1234,6 +1245,7 @@ Init_ossl_bn(void)
     rb_define_method(cBN, "mod_sub", ossl_bn_mod_sub, 2);
     rb_define_method(cBN, "mod_mul", ossl_bn_mod_mul, 2);
     rb_define_method(cBN, "mod_sqr", ossl_bn_mod_sqr, 1);
+    rb_define_method(cBN, "mod_sqrt", ossl_bn_mod_sqrt, 1);
     rb_define_method(cBN, "**", ossl_bn_exp, 1);
     rb_define_method(cBN, "mod_exp", ossl_bn_mod_exp, 2);
     rb_define_method(cBN, "gcd", ossl_bn_gcd, 1);
diff --git a/ext/openssl/ossl_cipher.c b/ext/openssl/ossl_cipher.c
index d9c7891433..cb8fbc3ca2 100644
--- a/ext/openssl/ossl_cipher.c
+++ b/ext/openssl/ossl_cipher.c
@@ -384,8 +384,7 @@ ossl_cipher_update(int argc, VALUE *argv, VALUE self)
 
     StringValue(data);
     in = (unsigned char *)RSTRING_PTR(data);
-    if ((in_len = RSTRING_LEN(data)) == 0)
-        ossl_raise(rb_eArgError, "data must not be empty");
+    in_len = RSTRING_LEN(data);
     GetCipher(self, ctx);
     out_len = in_len+EVP_CIPHER_CTX_block_size(ctx);
     if (out_len <= 0) {
diff --git a/ext/openssl/ossl_hmac.c b/ext/openssl/ossl_hmac.c
index bfe3a74b12..1a5f471a27 100644
--- a/ext/openssl/ossl_hmac.c
+++ b/ext/openssl/ossl_hmac.c
@@ -97,11 +97,19 @@ ossl_hmac_initialize(VALUE self, VALUE key, VALUE digest)
 
     GetHMAC(self, ctx);
     StringValue(key);
+#ifdef HAVE_EVP_PKEY_NEW_RAW_PRIVATE_KEY
+    pkey = EVP_PKEY_new_raw_private_key(EVP_PKEY_HMAC, NULL,
+                                        (unsigned char *)RSTRING_PTR(key),
+                                        RSTRING_LENINT(key));
+    if (!pkey)
+        ossl_raise(eHMACError, "EVP_PKEY_new_raw_private_key");
+#else
     pkey = EVP_PKEY_new_mac_key(EVP_PKEY_HMAC, NULL,
                                 (unsigned char *)RSTRING_PTR(key),
                                 RSTRING_LENINT(key));
     if (!pkey)
         ossl_raise(eHMACError, "EVP_PKEY_new_mac_key");
+#endif
     if (EVP_DigestSignInit(ctx, NULL, ossl_evp_get_digestbyname(digest),
                            NULL, pkey) != 1) {
         EVP_PKEY_free(pkey);
diff --git a/ext/openssl/ossl_kdf.c b/ext/openssl/ossl_kdf.c
index 7fa38b865e..0d25a7304b 100644
--- a/ext/openssl/ossl_kdf.c
+++ b/ext/openssl/ossl_kdf.c
@@ -3,7 +3,7 @@
  * Copyright (C) 2007, 2017 Ruby/OpenSSL Project Authors
  */
 #include "ossl.h"
-#if OPENSSL_VERSION_NUMBER >= 0x10100000 && !defined(LIBRESSL_VERSION_NUMBER)
+#if OSSL_OPENSSL_PREREQ(1, 1, 0) || OSSL_LIBRESSL_PREREQ(3, 6, 0)
 # include <openssl/kdf.h>
 #endif
 
@@ -141,7 +141,7 @@ kdf_scrypt(int argc, VALUE *argv, VALUE self)
 }
 #endif
 
-#if OPENSSL_VERSION_NUMBER >= 0x10100000 && !defined(LIBRESSL_VERSION_NUMBER)
+#if OSSL_OPENSSL_PREREQ(1, 1, 0) || OSSL_LIBRESSL_PREREQ(3, 6, 0)
 /*
  * call-seq:
  *    KDF.hkdf(ikm, salt:, info:, length:, hash:) -> String
@@ -305,7 +305,7 @@ Init_ossl_kdf(void)
 #if defined(HAVE_EVP_PBE_SCRYPT)
     rb_define_module_function(mKDF, "scrypt", kdf_scrypt, -1);
 #endif
-#if OPENSSL_VERSION_NUMBER >= 0x10100000 && !defined(LIBRESSL_VERSION_NUMBER)
+#if OSSL_OPENSSL_PREREQ(1, 1, 0) || OSSL_LIBRESSL_PREREQ(3, 6, 0)
     rb_define_module_function(mKDF, "hkdf", kdf_hkdf, -1);
 #endif
 }
diff --git a/ext/openssl/ossl_ocsp.c b/ext/openssl/ossl_ocsp.c
index 1e87484afc..9c8d768d87 100644
--- a/ext/openssl/ossl_ocsp.c
+++ b/ext/openssl/ossl_ocsp.c
@@ -382,7 +382,7 @@ ossl_ocspreq_sign(int argc, VALUE *argv, VALUE self)
     if (!NIL_P(flags))
 	flg = NUM2INT(flags);
     if (NIL_P(digest))
-	md = EVP_sha1();
+	md = NULL;
     else
 	md = ossl_evp_get_digestbyname(digest);
     if (NIL_P(certs))
@@ -1033,7 +1033,7 @@ ossl_ocspbres_sign(int argc, VALUE *argv, VALUE self)
     if (!NIL_P(flags))
 	flg = NUM2INT(flags);
     if (NIL_P(digest))
-	md = EVP_sha1();
+	md = NULL;
     else
 	md = ossl_evp_get_digestbyname(digest);
     if (NIL_P(certs))
diff --git a/ext/openssl/ossl_pkey.c b/ext/openssl/ossl_pkey.c
index 2a4835a28d..476256679b 100644
--- a/ext/openssl/ossl_pkey.c
+++ b/ext/openssl/ossl_pkey.c
@@ -99,17 +99,56 @@ ossl_pkey_read_generic(BIO *bio, VALUE pass)
     /* First check DER */
     if (OSSL_DECODER_from_bio(dctx, bio) == 1)
         goto out;
+    OSSL_BIO_reset(bio);
 
     /* Then check PEM; multiple OSSL_DECODER_from_bio() calls may be needed */
-    OSSL_BIO_reset(bio);
     if (OSSL_DECODER_CTX_set_input_type(dctx, "PEM") != 1)
         goto out;
-    while (OSSL_DECODER_from_bio(dctx, bio) != 1) {
-        if (BIO_eof(bio))
+    /*
+     * First check for private key formats. This is to keep compatibility with
+     * ruby/openssl < 3.0 which decoded the following as a private key.
+     *
+     *     $ openssl ecparam -name prime256v1 -genkey -outform PEM
+     *     -----BEGIN EC PARAMETERS-----
+     *     BggqhkjOPQMBBw==
+     *     -----END EC PARAMETERS-----
+     *     -----BEGIN EC PRIVATE KEY-----
+     *     MHcCAQEEIAG8ugBbA5MHkqnZ9ujQF93OyUfL9tk8sxqM5Wv5tKg5oAoGCCqGSM49
+     *     AwEHoUQDQgAEVcjhJfkwqh5C7kGuhAf8XaAjVuG5ADwb5ayg/cJijCgs+GcXeedj
+     *     86avKpGH84DXUlB23C/kPt+6fXYlitUmXQ==
+     *     -----END EC PRIVATE KEY-----
+     *
+     * While the first PEM block is a proper encoding of ECParameters, thus
+     * OSSL_DECODER_from_bio() would pick it up, ruby/openssl used to return
+     * the latter instead. Existing applications expect this behavior.
+     *
+     * Note that normally, the input is supposed to contain a single decodable
+     * PEM block only, so this special handling should not create a new problem.
+     */
+    OSSL_DECODER_CTX_set_selection(dctx, EVP_PKEY_KEYPAIR);
+    while (1) {
+        if (OSSL_DECODER_from_bio(dctx, bio) == 1)
             goto out;
+        if (BIO_eof(bio))
+            break;
         pos2 = BIO_tell(bio);
         if (pos2 < 0 || pos2 <= pos)
+            break;
+        ossl_clear_error();
+        pos = pos2;
+    }
+
+    OSSL_BIO_reset(bio);
+    OSSL_DECODER_CTX_set_selection(dctx, 0);
+    while (1) {
+        if (OSSL_DECODER_from_bio(dctx, bio) == 1)
             goto out;
+        if (BIO_eof(bio))
+            break;
+        pos2 = BIO_tell(bio);
+        if (pos2 < 0 || pos2 <= pos)
+            break;
+        ossl_clear_error();
         pos = pos2;
     }
 
@@ -200,6 +239,7 @@ static VALUE
 pkey_ctx_apply_options0(VALUE args_v)
 {
     VALUE *args = (VALUE *)args_v;
+    Check_Type(args[1], T_HASH);
 
     rb_block_call(args[1], rb_intern("each"), 0, NULL,
                   pkey_ctx_apply_options_i, args[0]);
@@ -670,7 +710,7 @@ ossl_pkey_export_traditional(int argc, VALUE *argv, VALUE self, int to_der)
 	}
     }
     else {
-#if OPENSSL_VERSION_NUMBER >= 0x10100000 && !defined(LIBRESSL_VERSION_NUMBER)
+#if OSSL_OPENSSL_PREREQ(1, 1, 0) || OSSL_LIBRESSL_PREREQ(3, 5, 0)
 	if (!PEM_write_bio_PrivateKey_traditional(bio, pkey, enc, NULL, 0,
 						  ossl_pem_passwd_cb,
 						  (void *)pass)) {
@@ -911,7 +951,7 @@ ossl_pkey_sign(int argc, VALUE *argv, VALUE self)
             rb_jump_tag(state);
         }
     }
-#if OPENSSL_VERSION_NUMBER >= 0x10101000 && !defined(LIBRESSL_VERSION_NUMBER)
+#if OSSL_OPENSSL_PREREQ(1, 1, 1) || OSSL_LIBRESSL_PREREQ(3, 4, 0)
     if (EVP_DigestSign(ctx, NULL, &siglen, (unsigned char *)RSTRING_PTR(data),
                        RSTRING_LEN(data)) < 1) {
         EVP_MD_CTX_free(ctx);
@@ -1016,7 +1056,7 @@ ossl_pkey_verify(int argc, VALUE *argv, VALUE self)
             rb_jump_tag(state);
         }
     }
-#if OPENSSL_VERSION_NUMBER >= 0x10101000 && !defined(LIBRESSL_VERSION_NUMBER)
+#if OSSL_OPENSSL_PREREQ(1, 1, 1) || OSSL_LIBRESSL_PREREQ(3, 4, 0)
     ret = EVP_DigestVerify(ctx, (unsigned char *)RSTRING_PTR(sig),
                            RSTRING_LEN(sig), (unsigned char *)RSTRING_PTR(data),
                            RSTRING_LEN(data));
diff --git a/ext/openssl/ossl_pkey.h b/ext/openssl/ossl_pkey.h
index 38fb9fad10..10669b824c 100644
--- a/ext/openssl/ossl_pkey.h
+++ b/ext/openssl/ossl_pkey.h
@@ -92,7 +92,7 @@ void Init_ossl_ec(void);
  */									\
 static VALUE ossl_##_keytype##_get_##_name(VALUE self)			\
 {									\
-	_type *obj;							\
+	const _type *obj;						\
 	const BIGNUM *bn;						\
 									\
 	Get##_type(self, obj);						\
diff --git a/ext/openssl/ossl_pkey_dh.c b/ext/openssl/ossl_pkey_dh.c
index 696455dcfd..83c41378fe 100644
--- a/ext/openssl/ossl_pkey_dh.c
+++ b/ext/openssl/ossl_pkey_dh.c
@@ -178,7 +178,7 @@ ossl_dh_initialize_copy(VALUE self, VALUE other)
 static VALUE
 ossl_dh_is_public(VALUE self)
 {
-    DH *dh;
+    OSSL_3_const DH *dh;
     const BIGNUM *bn;
 
     GetDH(self, dh);
@@ -197,14 +197,14 @@ ossl_dh_is_public(VALUE self)
 static VALUE
 ossl_dh_is_private(VALUE self)
 {
-    DH *dh;
+    OSSL_3_const DH *dh;
     const BIGNUM *bn;
 
     GetDH(self, dh);
     DH_get0_key(dh, NULL, &bn);
 
 #if !defined(OPENSSL_NO_ENGINE)
-    return (bn || DH_get0_engine(dh)) ? Qtrue : Qfalse;
+    return (bn || DH_get0_engine((DH *)dh)) ? Qtrue : Qfalse;
 #else
     return bn ? Qtrue : Qfalse;
 #endif
@@ -223,7 +223,7 @@ ossl_dh_is_private(VALUE self)
 static VALUE
 ossl_dh_export(VALUE self)
 {
-    DH *dh;
+    OSSL_3_const DH *dh;
     BIO *out;
     VALUE str;
 
@@ -252,7 +252,7 @@ ossl_dh_export(VALUE self)
 static VALUE
 ossl_dh_to_der(VALUE self)
 {
-    DH *dh;
+    OSSL_3_const DH *dh;
     unsigned char *p;
     long len;
     VALUE str;
@@ -280,7 +280,7 @@ ossl_dh_to_der(VALUE self)
 static VALUE
 ossl_dh_get_params(VALUE self)
 {
-    DH *dh;
+    OSSL_3_const DH *dh;
     VALUE hash;
     const BIGNUM *p, *q, *g, *pub_key, *priv_key;
 
diff --git a/ext/openssl/ossl_pkey_dsa.c b/ext/openssl/ossl_pkey_dsa.c
index 25404aa7f5..b097f8c9d2 100644
--- a/ext/openssl/ossl_pkey_dsa.c
+++ b/ext/openssl/ossl_pkey_dsa.c
@@ -24,7 +24,7 @@
 } while (0)
 
 static inline int
-DSA_HAS_PRIVATE(DSA *dsa)
+DSA_HAS_PRIVATE(OSSL_3_const DSA *dsa)
 {
     const BIGNUM *bn;
     DSA_get0_key(dsa, NULL, &bn);
@@ -32,7 +32,7 @@ DSA_HAS_PRIVATE(DSA *dsa)
 }
 
 static inline int
-DSA_PRIVATE(VALUE obj, DSA *dsa)
+DSA_PRIVATE(VALUE obj, OSSL_3_const DSA *dsa)
 {
     return DSA_HAS_PRIVATE(dsa) || OSSL_PKEY_IS_PRIVATE(obj);
 }
@@ -179,7 +179,7 @@ ossl_dsa_initialize_copy(VALUE self, VALUE other)
 static VALUE
 ossl_dsa_is_public(VALUE self)
 {
-    DSA *dsa;
+    const DSA *dsa;
     const BIGNUM *bn;
 
     GetDSA(self, dsa);
@@ -198,7 +198,7 @@ ossl_dsa_is_public(VALUE self)
 static VALUE
 ossl_dsa_is_private(VALUE self)
 {
-    DSA *dsa;
+    OSSL_3_const DSA *dsa;
 
     GetDSA(self, dsa);
 
@@ -225,7 +225,7 @@ ossl_dsa_is_private(VALUE self)
 static VALUE
 ossl_dsa_export(int argc, VALUE *argv, VALUE self)
 {
-    DSA *dsa;
+    OSSL_3_const DSA *dsa;
 
     GetDSA(self, dsa);
     if (DSA_HAS_PRIVATE(dsa))
@@ -244,7 +244,7 @@ ossl_dsa_export(int argc, VALUE *argv, VALUE self)
 static VALUE
 ossl_dsa_to_der(VALUE self)
 {
-    DSA *dsa;
+    OSSL_3_const DSA *dsa;
 
     GetDSA(self, dsa);
     if (DSA_HAS_PRIVATE(dsa))
@@ -265,7 +265,7 @@ ossl_dsa_to_der(VALUE self)
 static VALUE
 ossl_dsa_get_params(VALUE self)
 {
-    DSA *dsa;
+    OSSL_3_const DSA *dsa;
     VALUE hash;
     const BIGNUM *p, *q, *g, *pub_key, *priv_key;
 
diff --git a/ext/openssl/ossl_pkey_ec.c b/ext/openssl/ossl_pkey_ec.c
index dee215447d..92842f95ac 100644
--- a/ext/openssl/ossl_pkey_ec.c
+++ b/ext/openssl/ossl_pkey_ec.c
@@ -227,7 +227,7 @@ ossl_ec_key_initialize_copy(VALUE self, VALUE other)
 static VALUE
 ossl_ec_key_get_group(VALUE self)
 {
-    EC_KEY *ec;
+    OSSL_3_const EC_KEY *ec;
     const EC_GROUP *group;
 
     GetEC(self, ec);
@@ -272,7 +272,7 @@ ossl_ec_key_set_group(VALUE self, VALUE group_v)
  */
 static VALUE ossl_ec_key_get_private_key(VALUE self)
 {
-    EC_KEY *ec;
+    OSSL_3_const EC_KEY *ec;
     const BIGNUM *bn;
 
     GetEC(self, ec);
@@ -323,7 +323,7 @@ static VALUE ossl_ec_key_set_private_key(VALUE self, VALUE private_key)
  */
 static VALUE ossl_ec_key_get_public_key(VALUE self)
 {
-    EC_KEY *ec;
+    OSSL_3_const EC_KEY *ec;
     const EC_POINT *point;
 
     GetEC(self, ec);
@@ -375,7 +375,7 @@ static VALUE ossl_ec_key_set_public_key(VALUE self, VALUE public_key)
  */
 static VALUE ossl_ec_key_is_public(VALUE self)
 {
-    EC_KEY *ec;
+    OSSL_3_const EC_KEY *ec;
 
     GetEC(self, ec);
 
@@ -391,7 +391,7 @@ static VALUE ossl_ec_key_is_public(VALUE self)
  */
 static VALUE ossl_ec_key_is_private(VALUE self)
 {
-    EC_KEY *ec;
+    OSSL_3_const EC_KEY *ec;
 
     GetEC(self, ec);
 
@@ -411,9 +411,11 @@ static VALUE ossl_ec_key_is_private(VALUE self)
 static VALUE
 ossl_ec_key_export(int argc, VALUE *argv, VALUE self)
 {
-    EC_KEY *ec;
+    OSSL_3_const EC_KEY *ec;
 
     GetEC(self, ec);
+    if (EC_KEY_get0_public_key(ec) == NULL)
+        ossl_raise(eECError, "can't export - no public key set");
     if (EC_KEY_get0_private_key(ec))
         return ossl_pkey_export_traditional(argc, argv, self, 0);
     else
@@ -429,9 +431,11 @@ ossl_ec_key_export(int argc, VALUE *argv, VALUE self)
 static VALUE
 ossl_ec_key_to_der(VALUE self)
 {
-    EC_KEY *ec;
+    OSSL_3_const EC_KEY *ec;
 
     GetEC(self, ec);
+    if (EC_KEY_get0_public_key(ec) == NULL)
+        ossl_raise(eECError, "can't export - no public key set");
     if (EC_KEY_get0_private_key(ec))
         return ossl_pkey_export_traditional(0, NULL, self, 1);
     else
@@ -479,16 +483,28 @@ static VALUE ossl_ec_key_check_key(VALUE self)
 #ifdef HAVE_EVP_PKEY_CHECK
     EVP_PKEY *pkey;
     EVP_PKEY_CTX *pctx;
-    int ret;
+    const EC_KEY *ec;
 
     GetPKey(self, pkey);
+    GetEC(self, ec);
     pctx = EVP_PKEY_CTX_new(pkey, /* engine */NULL);
     if (!pctx)
-        ossl_raise(eDHError, "EVP_PKEY_CTX_new");
-    ret = EVP_PKEY_public_check(pctx);
+        ossl_raise(eECError, "EVP_PKEY_CTX_new");
+
+    if (EC_KEY_get0_private_key(ec) != NULL) {
+        if (EVP_PKEY_check(pctx) != 1) {
+            EVP_PKEY_CTX_free(pctx);
+            ossl_raise(eECError, "EVP_PKEY_check");
+        }
+    }
+    else {
+        if (EVP_PKEY_public_check(pctx) != 1) {
+            EVP_PKEY_CTX_free(pctx);
+            ossl_raise(eECError, "EVP_PKEY_public_check");
+        }
+    }
+
     EVP_PKEY_CTX_free(pctx);
-    if (ret != 1)
-        ossl_raise(eECError, "EVP_PKEY_public_check");
 #else
     EC_KEY *ec;
 
@@ -664,10 +680,11 @@ static VALUE ossl_ec_group_eql(VALUE a, VALUE b)
     GetECGroup(a, group1);
     GetECGroup(b, group2);
 
-    if (EC_GROUP_cmp(group1, group2, ossl_bn_ctx) == 1)
-       return Qfalse;
-
-    return Qtrue;
+    switch (EC_GROUP_cmp(group1, group2, ossl_bn_ctx)) {
+    case 0: return Qtrue;
+    case 1: return Qfalse;
+    default: ossl_raise(eEC_GROUP, "EC_GROUP_cmp");
+    }
 }
 
 /*
@@ -1228,10 +1245,13 @@ static VALUE ossl_ec_point_eql(VALUE a, VALUE b)
     GetECPoint(b, point2);
     GetECGroup(group_v1, group);
 
-    if (EC_POINT_cmp(group, point1, point2, ossl_bn_ctx) == 1)
-        return Qfalse;
+    switch (EC_POINT_cmp(group, point1, point2, ossl_bn_ctx)) {
+    case 0: return Qtrue;
+    case 1: return Qfalse;
+    default: ossl_raise(eEC_POINT, "EC_POINT_cmp");
+    }
 
-    return Qtrue;
+    UNREACHABLE;
 }
 
 /*
@@ -1249,7 +1269,7 @@ static VALUE ossl_ec_point_is_at_infinity(VALUE self)
     switch (EC_POINT_is_at_infinity(group, point)) {
     case 1: return Qtrue;
     case 0: return Qfalse;
-    default: ossl_raise(cEC_POINT, "EC_POINT_is_at_infinity");
+    default: ossl_raise(eEC_POINT, "EC_POINT_is_at_infinity");
     }
 
     UNREACHABLE;
@@ -1270,7 +1290,7 @@ static VALUE ossl_ec_point_is_on_curve(VALUE self)
     switch (EC_POINT_is_on_curve(group, point, ossl_bn_ctx)) {
     case 1: return Qtrue;
     case 0: return Qfalse;
-    default: ossl_raise(cEC_POINT, "EC_POINT_is_on_curve");
+    default: ossl_raise(eEC_POINT, "EC_POINT_is_on_curve");
     }
 
     UNREACHABLE;
@@ -1293,7 +1313,7 @@ static VALUE ossl_ec_point_make_affine(VALUE self)
     rb_warn("OpenSSL::PKey::EC::Point#make_affine! is deprecated");
 #if !OSSL_OPENSSL_PREREQ(3, 0, 0)
     if (EC_POINT_make_affine(group, point, ossl_bn_ctx) != 1)
-        ossl_raise(cEC_POINT, "EC_POINT_make_affine");
+        ossl_raise(eEC_POINT, "EC_POINT_make_affine");
 #endif
 
     return self;
@@ -1312,7 +1332,7 @@ static VALUE ossl_ec_point_invert(VALUE self)
     GetECPointGroup(self, group);
 
     if (EC_POINT_invert(group, point, ossl_bn_ctx) != 1)
-        ossl_raise(cEC_POINT, "EC_POINT_invert");
+        ossl_raise(eEC_POINT, "EC_POINT_invert");
 
     return self;
 }
@@ -1330,7 +1350,7 @@ static VALUE ossl_ec_point_set_to_infinity(VALUE self)
     GetECPointGroup(self, group);
 
     if (EC_POINT_set_to_infinity(group, point) != 1)
-        ossl_raise(cEC_POINT, "EC_POINT_set_to_infinity");
+        ossl_raise(eEC_POINT, "EC_POINT_set_to_infinity");
 
     return self;
 }
diff --git a/ext/openssl/ossl_pkey_rsa.c b/ext/openssl/ossl_pkey_rsa.c
index 4d66010f49..072adabe62 100644
--- a/ext/openssl/ossl_pkey_rsa.c
+++ b/ext/openssl/ossl_pkey_rsa.c
@@ -24,7 +24,7 @@
 } while (0)
 
 static inline int
-RSA_HAS_PRIVATE(RSA *rsa)
+RSA_HAS_PRIVATE(OSSL_3_const RSA *rsa)
 {
     const BIGNUM *e, *d;
 
@@ -33,7 +33,7 @@ RSA_HAS_PRIVATE(RSA *rsa)
 }
 
 static inline int
-RSA_PRIVATE(VALUE obj, RSA *rsa)
+RSA_PRIVATE(VALUE obj, OSSL_3_const RSA *rsa)
 {
     return RSA_HAS_PRIVATE(rsa) || OSSL_PKEY_IS_PRIVATE(obj);
 }
@@ -174,7 +174,7 @@ ossl_rsa_initialize_copy(VALUE self, VALUE other)
 static VALUE
 ossl_rsa_is_public(VALUE self)
 {
-    RSA *rsa;
+    OSSL_3_const RSA *rsa;
 
     GetRSA(self, rsa);
     /*
@@ -193,7 +193,7 @@ ossl_rsa_is_public(VALUE self)
 static VALUE
 ossl_rsa_is_private(VALUE self)
 {
-    RSA *rsa;
+    OSSL_3_const RSA *rsa;
 
     GetRSA(self, rsa);
 
@@ -203,7 +203,7 @@ ossl_rsa_is_private(VALUE self)
 static int
 can_export_rsaprivatekey(VALUE self)
 {
-    RSA *rsa;
+    OSSL_3_const RSA *rsa;
     const BIGNUM *n, *e, *d, *p, *q, *dmp1, *dmq1, *iqmp;
 
     GetRSA(self, rsa);
@@ -453,7 +453,7 @@ ossl_rsa_verify_pss(int argc, VALUE *argv, VALUE self)
 static VALUE
 ossl_rsa_get_params(VALUE self)
 {
-    RSA *rsa;
+    OSSL_3_const RSA *rsa;
     VALUE hash;
     const BIGNUM *n, *e, *d, *p, *q, *dmp1, *dmq1, *iqmp;
 
diff --git a/ext/openssl/ossl_ssl.c b/ext/openssl/ossl_ssl.c
index 9a0682a7cd..f63992664a 100644
--- a/ext/openssl/ossl_ssl.c
+++ b/ext/openssl/ossl_ssl.c
@@ -11,11 +11,15 @@
  */
 #include "ossl.h"
 
+#ifndef OPENSSL_NO_SOCK
 #define numberof(ary) (int)(sizeof(ary)/sizeof((ary)[0]))
 
+#if !defined(OPENSSL_NO_NEXTPROTONEG) && !OSSL_IS_LIBRESSL
+# define OSSL_USE_NEXTPROTONEG
+#endif
+
 #if !defined(TLS1_3_VERSION) && \
-    defined(LIBRESSL_VERSION_NUMBER) && \
-    LIBRESSL_VERSION_NUMBER >= 0x3020000fL
+    OSSL_LIBRESSL_PREREQ(3, 2, 0) && !OSSL_LIBRESSL_PREREQ(3, 4, 0)
 #  define TLS1_3_VERSION 0x0304
 #endif
 
@@ -30,7 +34,6 @@
 } while (0)
 
 VALUE mSSL;
-static VALUE mSSLExtConfig;
 static VALUE eSSLError;
 VALUE cSSLContext;
 VALUE cSSLSocket;
@@ -49,7 +52,7 @@ static ID id_i_cert_store, id_i_ca_file, id_i_ca_path, id_i_verify_mode,
 	  id_i_session_id_context, id_i_session_get_cb, id_i_session_new_cb,
 	  id_i_session_remove_cb, id_i_npn_select_cb, id_i_npn_protocols,
 	  id_i_alpn_select_cb, id_i_alpn_protocols, id_i_servername_cb,
-	  id_i_verify_hostname;
+	  id_i_verify_hostname, id_i_keylog_cb;
 static ID id_i_io, id_i_context, id_i_hostname;
 
 static int ossl_ssl_ex_vcb_idx;
@@ -291,7 +294,7 @@ ossl_tmp_dh_callback(SSL *ssl, int is_export, int keylength)
     if (!pkey)
 	return NULL;
 
-    return EVP_PKEY_get0_DH(pkey);
+    return (DH *)EVP_PKEY_get0_DH(pkey);
 }
 #endif /* OPENSSL_NO_DH */
 
@@ -441,6 +444,54 @@ ossl_sslctx_session_new_cb(SSL *ssl, SSL_SESSION *sess)
     return 0;
 }
 
+#if OPENSSL_VERSION_NUMBER >= 0x10101000 && !defined(LIBRESSL_VERSION_NUMBER)
+/*
+ * It is only compatible with OpenSSL >= 1.1.1. Even if LibreSSL implements
+ * SSL_CTX_set_keylog_callback() from v3.4.2, it does nothing (see
+ * https://github.com/libressl-portable/openbsd/commit/648d39f0f035835d0653342d139883b9661e9cb6).
+ */
+
+struct ossl_call_keylog_cb_args {
+    VALUE ssl_obj;
+    const char * line;
+};
+
+static VALUE
+ossl_call_keylog_cb(VALUE args_v)
+{
+    VALUE sslctx_obj, cb, line_v;
+    struct ossl_call_keylog_cb_args *args = (struct ossl_call_keylog_cb_args *) args_v;
+
+    sslctx_obj = rb_attr_get(args->ssl_obj, id_i_context);
+
+    cb = rb_attr_get(sslctx_obj, id_i_keylog_cb);
+    if (NIL_P(cb)) return Qnil;
+
+    line_v = rb_str_new_cstr(args->line);
+
+    return rb_funcall(cb, id_call, 2, args->ssl_obj, line_v);
+}
+
+static void
+ossl_sslctx_keylog_cb(const SSL *ssl, const char *line)
+{
+    VALUE ssl_obj;
+    struct ossl_call_keylog_cb_args args;
+    int state = 0;
+
+    OSSL_Debug("SSL keylog callback entered");
+
+    ssl_obj = (VALUE)SSL_get_ex_data(ssl, ossl_ssl_ex_ptr_idx);
+    args.ssl_obj = ssl_obj;
+    args.line = line;
+
+    rb_protect(ossl_call_keylog_cb, (VALUE)&args, &state);
+    if (state) {
+        rb_ivar_set(ssl_obj, ID_callback_state, INT2NUM(state));
+    }
+}
+#endif
+
 static VALUE
 ossl_call_session_remove_cb(VALUE ary)
 {
@@ -655,7 +706,7 @@ ssl_npn_select_cb_common(SSL *ssl, VALUE cb, const unsigned char **out,
     return SSL_TLSEXT_ERR_OK;
 }
 
-#ifndef OPENSSL_NO_NEXTPROTONEG
+#ifdef OSSL_USE_NEXTPROTONEG
 static int
 ssl_npn_advertise_cb(SSL *ssl, const unsigned char **out, unsigned int *outlen,
 		     void *arg)
@@ -852,7 +903,7 @@ ossl_sslctx_setup(VALUE self)
     val = rb_attr_get(self, id_i_verify_depth);
     if(!NIL_P(val)) SSL_CTX_set_verify_depth(ctx, NUM2INT(val));
 
-#ifndef OPENSSL_NO_NEXTPROTONEG
+#ifdef OSSL_USE_NEXTPROTONEG
     val = rb_attr_get(self, id_i_npn_protocols);
     if (!NIL_P(val)) {
 	VALUE encoded = ssl_encode_npn_protocols(val);
@@ -911,6 +962,18 @@ ossl_sslctx_setup(VALUE self)
 	OSSL_Debug("SSL TLSEXT servername callback added");
     }
 
+#if OPENSSL_VERSION_NUMBER >= 0x10101000 && !defined(LIBRESSL_VERSION_NUMBER)
+    /*
+     * It is only compatible with OpenSSL >= 1.1.1. Even if LibreSSL implements
+     * SSL_CTX_set_keylog_callback() from v3.4.2, it does nothing (see
+     * https://github.com/libressl-portable/openbsd/commit/648d39f0f035835d0653342d139883b9661e9cb6).
+     */
+    if (RTEST(rb_attr_get(self, id_i_keylog_cb))) {
+        SSL_CTX_set_keylog_callback(ctx, ossl_sslctx_keylog_cb);
+        OSSL_Debug("SSL keylog callback added");
+    }
+#endif
+
     return Qtrue;
 }
 
@@ -959,27 +1022,13 @@ ossl_sslctx_get_ciphers(VALUE self)
     return ary;
 }
 
-/*
- * call-seq:
- *    ctx.ciphers = "cipher1:cipher2:..."
- *    ctx.ciphers = [name, ...]
- *    ctx.ciphers = [[name, version, bits, alg_bits], ...]
- *
- * Sets the list of available cipher suites for this context.  Note in a server
- * context some ciphers require the appropriate certificates.  For example, an
- * RSA cipher suite can only be chosen when an RSA certificate is available.
- */
 static VALUE
-ossl_sslctx_set_ciphers(VALUE self, VALUE v)
+build_cipher_string(VALUE v)
 {
-    SSL_CTX *ctx;
     VALUE str, elem;
     int i;
 
-    rb_check_frozen(self);
-    if (NIL_P(v))
-	return v;
-    else if (RB_TYPE_P(v, T_ARRAY)) {
+    if (RB_TYPE_P(v, T_ARRAY)) {
         str = rb_str_new(0, 0);
         for (i = 0; i < RARRAY_LEN(v); i++) {
             elem = rb_ary_entry(v, i);
@@ -993,14 +1042,67 @@ ossl_sslctx_set_ciphers(VALUE self, VALUE v)
         StringValue(str);
     }
 
+    return str;
+}
+
+/*
+ * call-seq:
+ *    ctx.ciphers = "cipher1:cipher2:..."
+ *    ctx.ciphers = [name, ...]
+ *    ctx.ciphers = [[name, version, bits, alg_bits], ...]
+ *
+ * Sets the list of available cipher suites for this context.  Note in a server
+ * context some ciphers require the appropriate certificates.  For example, an
+ * RSA cipher suite can only be chosen when an RSA certificate is available.
+ */
+static VALUE
+ossl_sslctx_set_ciphers(VALUE self, VALUE v)
+{
+    SSL_CTX *ctx;
+    VALUE str;
+
+    rb_check_frozen(self);
+    if (NIL_P(v))
+        return v;
+
+    str = build_cipher_string(v);
+
     GetSSLCTX(self, ctx);
-    if (!SSL_CTX_set_cipher_list(ctx, StringValueCStr(str))) {
+    if (!SSL_CTX_set_cipher_list(ctx, StringValueCStr(str)))
         ossl_raise(eSSLError, "SSL_CTX_set_cipher_list");
-    }
 
     return v;
 }
 
+#ifdef HAVE_SSL_CTX_SET_CIPHERSUITES
+/*
+ * call-seq:
+ *    ctx.ciphersuites = "cipher1:cipher2:..."
+ *    ctx.ciphersuites = [name, ...]
+ *    ctx.ciphersuites = [[name, version, bits, alg_bits], ...]
+ *
+ * Sets the list of available TLSv1.3 cipher suites for this context.
+ */
+static VALUE
+ossl_sslctx_set_ciphersuites(VALUE self, VALUE v)
+{
+    SSL_CTX *ctx;
+    VALUE str;
+
+    rb_check_frozen(self);
+    if (NIL_P(v))
+        return v;
+
+    str = build_cipher_string(v);
+
+    GetSSLCTX(self, ctx);
+    if (!SSL_CTX_set_ciphersuites(ctx, StringValueCStr(str)))
+        ossl_raise(eSSLError, "SSL_CTX_set_ciphersuites");
+
+    return v;
+}
+#endif
+
 #ifndef OPENSSL_NO_DH
 /*
  * call-seq:
@@ -1439,7 +1541,6 @@ ossl_sslctx_flush_sessions(int argc, VALUE *argv, VALUE self)
 /*
  * SSLSocket class
  */
-#ifndef OPENSSL_NO_SOCK
 static inline int
 ssl_started(SSL *ssl)
 {
@@ -1602,11 +1703,16 @@ no_exception_p(VALUE opts)
     return 0;
 }
 
+// Provided by Ruby 3.2.0 and later in order to support the default IO#timeout.
+#ifndef RUBY_IO_TIMEOUT_DEFAULT
+#define RUBY_IO_TIMEOUT_DEFAULT Qnil
+#endif
+
 static void
 io_wait_writable(rb_io_t *fptr)
 {
 #ifdef HAVE_RB_IO_MAYBE_WAIT
-    rb_io_maybe_wait_writable(errno, fptr->self, Qnil);
+    rb_io_maybe_wait_writable(errno, fptr->self, RUBY_IO_TIMEOUT_DEFAULT);
 #else
     rb_io_wait_writable(fptr->fd);
 #endif
@@ -1616,14 +1722,14 @@ static void
 io_wait_readable(rb_io_t *fptr)
 {
 #ifdef HAVE_RB_IO_MAYBE_WAIT
-    rb_io_maybe_wait_readable(errno, fptr->self, Qnil);
+    rb_io_maybe_wait_readable(errno, fptr->self, RUBY_IO_TIMEOUT_DEFAULT);
 #else
     rb_io_wait_readable(fptr->fd);
 #endif
 }
 
 static VALUE
-ossl_start_ssl(VALUE self, int (*func)(), const char *funcname, VALUE opts)
+ossl_start_ssl(VALUE self, int (*func)(SSL *), const char *funcname, VALUE opts)
 {
     SSL *ssl;
     rb_io_t *fptr;
@@ -2342,7 +2448,7 @@ ossl_ssl_get_client_ca_list(VALUE self)
     return ossl_x509name_sk2ary(ca);
 }
 
-# ifndef OPENSSL_NO_NEXTPROTONEG
+# ifdef OSSL_USE_NEXTPROTONEG
 /*
  * call-seq:
  *    ssl.npn_protocol => String | nil
@@ -2392,6 +2498,49 @@ ossl_ssl_alpn_protocol(VALUE self)
 
 /*
  * call-seq:
+ *    session.export_keying_material(label, length) -> String
+ *
+ * Enables use of shared session key material in accordance with RFC 5705.
+ */
+static VALUE
+ossl_ssl_export_keying_material(int argc, VALUE *argv, VALUE self)
+{
+    SSL *ssl;
+    VALUE str;
+    VALUE label;
+    VALUE length;
+    VALUE context;
+    unsigned char *p;
+    size_t len;
+    int use_ctx = 0;
+    unsigned char *ctx = NULL;
+    size_t ctx_len = 0;
+    int ret;
+
+    rb_scan_args(argc, argv, "21", &label, &length, &context);
+    StringValue(label);
+
+    GetSSL(self, ssl);
+
+    len = (size_t)NUM2LONG(length);
+    str = rb_str_new(0, len);
+    p = (unsigned char *)RSTRING_PTR(str);
+    if (!NIL_P(context)) {
+	use_ctx = 1;
+	StringValue(context);
+	ctx = (unsigned char *)RSTRING_PTR(context);
+	ctx_len = RSTRING_LEN(context);
+    }
+    ret = SSL_export_keying_material(ssl, p, len, (char *)RSTRING_PTR(label),
+				     RSTRING_LENINT(label), ctx, ctx_len, use_ctx);
+    if (ret == 0 || ret == -1) {
+	ossl_raise(eSSLError, "SSL_export_keying_material");
+    }
+    return str;
+}
+
+/*
+ * call-seq:
  *    ssl.tmp_key => PKey or nil
  *
  * Returns the ephemeral key used in case of forward secrecy cipher.
@@ -2419,6 +2568,7 @@ Init_ossl_ssl(void)
     rb_mWaitWritable = rb_define_module_under(rb_cIO, "WaitWritable");
 #endif
 
+#ifndef OPENSSL_NO_SOCK
     id_call = rb_intern_const("call");
     ID_callback_state = rb_intern_const("callback_state");
 
@@ -2441,16 +2591,6 @@ Init_ossl_ssl(void)
      */
     mSSL = rb_define_module_under(mOSSL, "SSL");
 
-    /* Document-module: OpenSSL::ExtConfig
-     *
-     * This module contains configuration information about the SSL extension,
-     * for example if socket support is enabled, or the host name TLS extension
-     * is enabled.  Constants in this module will always be defined, but contain
-     * +true+ or +false+ values depending on the configuration of your OpenSSL
-     * installation.
-     */
-    mSSLExtConfig = rb_define_module_under(mOSSL, "ExtConfig");
-
     /* Document-class: OpenSSL::SSL::SSLError
      *
      * Generic error class raised by SSLSocket and SSLContext.
@@ -2613,8 +2753,6 @@ Init_ossl_ssl(void)
      */
     rb_attr(cSSLContext, rb_intern_const("session_remove_cb"), 1, 1, Qfalse);
 
-    rb_define_const(mSSLExtConfig, "HAVE_TLSEXT_HOST_NAME", Qtrue);
-
     /*
      * A callback invoked whenever a new handshake is initiated on an
      * established connection. May be used to disable renegotiation entirely.
@@ -2635,7 +2773,7 @@ Init_ossl_ssl(void)
      *   end
      */
     rb_attr(cSSLContext, rb_intern_const("renegotiation_cb"), 1, 1, Qfalse);
-#ifndef OPENSSL_NO_NEXTPROTONEG
+#ifdef OSSL_USE_NEXTPROTONEG
     /*
      * An Enumerable of Strings. Each String represents a protocol to be
      * advertised as the list of supported protocols for Next Protocol
@@ -2697,12 +2835,38 @@ Init_ossl_ssl(void)
      */
     rb_attr(cSSLContext, rb_intern_const("alpn_select_cb"), 1, 1, Qfalse);
 
+    /*
+     * A callback invoked when TLS key material is generated or received, in
+     * order to allow applications to store this keying material for debugging
+     * purposes.
+     *
+     * The callback is invoked with an SSLSocket and a string containing the
+     * key material in the format used by NSS for its SSLKEYLOGFILE debugging
+     * output.
+     *
+     * It is only compatible with OpenSSL >= 1.1.1. Even if LibreSSL implements
+     * SSL_CTX_set_keylog_callback() from v3.4.2, it does nothing (see
+     * https://github.com/libressl-portable/openbsd/commit/648d39f0f035835d0653342d139883b9661e9cb6).
+     *
+     * === Example
+     *
+     *   context.keylog_cb = proc do |_sock, line|
+     *     File.open('ssl_keylog_file', "a") do |f|
+     *       f.write("#{line}\n")
+     *     end
+     *   end
+     */
+    rb_attr(cSSLContext, rb_intern_const("keylog_cb"), 1, 1, Qfalse);
+
     rb_define_alias(cSSLContext, "ssl_timeout", "timeout");
     rb_define_alias(cSSLContext, "ssl_timeout=", "timeout=");
     rb_define_private_method(cSSLContext, "set_minmax_proto_version",
 			     ossl_sslctx_set_minmax_proto_version, 2);
     rb_define_method(cSSLContext, "ciphers",     ossl_sslctx_get_ciphers, 0);
     rb_define_method(cSSLContext, "ciphers=",    ossl_sslctx_set_ciphers, 1);
+#ifdef HAVE_SSL_CTX_SET_CIPHERSUITES
+    rb_define_method(cSSLContext, "ciphersuites=", ossl_sslctx_set_ciphersuites, 1);
+#endif
 #ifndef OPENSSL_NO_DH
     rb_define_method(cSSLContext, "tmp_dh=", ossl_sslctx_set_tmp_dh, 1);
 #endif
@@ -2779,11 +2943,6 @@ Init_ossl_ssl(void)
      * Document-class: OpenSSL::SSL::SSLSocket
      */
     cSSLSocket = rb_define_class_under(mSSL, "SSLSocket", rb_cObject);
-#ifdef OPENSSL_NO_SOCK
-    rb_define_const(mSSLExtConfig, "OPENSSL_NO_SOCK", Qtrue);
-    rb_define_method(cSSLSocket, "initialize", rb_f_notimplement, -1);
-#else
-    rb_define_const(mSSLExtConfig, "OPENSSL_NO_SOCK", Qfalse);
     rb_define_alloc_func(cSSLSocket, ossl_ssl_s_alloc);
     rb_define_method(cSSLSocket, "initialize", ossl_ssl_initialize, -1);
     rb_undef_method(cSSLSocket, "initialize_copy");
@@ -2814,10 +2973,10 @@ Init_ossl_ssl(void)
     rb_define_method(cSSLSocket, "peer_finished_message", ossl_ssl_get_peer_finished, 0);
     rb_define_method(cSSLSocket, "tmp_key", ossl_ssl_tmp_key, 0);
     rb_define_method(cSSLSocket, "alpn_protocol", ossl_ssl_alpn_protocol, 0);
-# ifndef OPENSSL_NO_NEXTPROTONEG
+    rb_define_method(cSSLSocket, "export_keying_material", ossl_ssl_export_keying_material, -1);
+# ifdef OSSL_USE_NEXTPROTONEG
     rb_define_method(cSSLSocket, "npn_protocol", ossl_ssl_npn_protocol, 0);
 # endif
-#endif
 
     rb_define_const(mSSL, "VERIFY_NONE", INT2NUM(SSL_VERIFY_NONE));
     rb_define_const(mSSL, "VERIFY_PEER", INT2NUM(SSL_VERIFY_PEER));
@@ -2974,8 +3133,10 @@ Init_ossl_ssl(void)
     DefIVarID(alpn_select_cb);
     DefIVarID(servername_cb);
     DefIVarID(verify_hostname);
+    DefIVarID(keylog_cb);
 
     DefIVarID(io);
     DefIVarID(context);
     DefIVarID(hostname);
+#endif /* !defined(OPENSSL_NO_SOCK) */
 }
diff --git a/ext/openssl/ossl_ssl_session.c b/ext/openssl/ossl_ssl_session.c
index 92eb1365fe..139a474b04 100644
--- a/ext/openssl/ossl_ssl_session.c
+++ b/ext/openssl/ossl_ssl_session.c
@@ -4,6 +4,7 @@
 
 #include "ossl.h"
 
+#ifndef OPENSSL_NO_SOCK
 VALUE cSSLSession;
 static VALUE eSSLSession;
 
@@ -299,6 +300,7 @@ static VALUE ossl_ssl_session_to_text(VALUE self)
 	return ossl_membio2str(out);
 }
 
+#endif /* !defined(OPENSSL_NO_SOCK) */
 
 void Init_ossl_ssl_session(void)
 {
@@ -307,6 +309,7 @@ void Init_ossl_ssl_session(void)
     mSSL = rb_define_module_under(mOSSL, "SSL");
     eOSSLError = rb_define_class_under(mOSSL, "OpenSSLError", rb_eStandardError);
 #endif
+#ifndef OPENSSL_NO_SOCK
 	cSSLSession = rb_define_class_under(mSSL, "Session", rb_cObject);
 	eSSLSession = rb_define_class_under(cSSLSession, "SessionError", eOSSLError);
 
@@ -324,4 +327,5 @@ void Init_ossl_ssl_session(void)
 	rb_define_method(cSSLSession, "to_der", ossl_ssl_session_to_der, 0);
 	rb_define_method(cSSLSession, "to_pem", ossl_ssl_session_to_pem, 0);
 	rb_define_method(cSSLSession, "to_text", ossl_ssl_session_to_text, 0);
+#endif /* !defined(OPENSSL_NO_SOCK) */
 }
diff --git a/ext/openssl/ossl_x509cert.c b/ext/openssl/ossl_x509cert.c
index 996f184170..9443541645 100644
--- a/ext/openssl/ossl_x509cert.c
+++ b/ext/openssl/ossl_x509cert.c
@@ -642,12 +642,12 @@ ossl_x509_set_extensions(VALUE self, VALUE ary)
 	OSSL_Check_Kind(RARRAY_AREF(ary, i), cX509Ext);
     }
     GetX509(self, x509);
-    while ((ext = X509_delete_ext(x509, 0)))
-	X509_EXTENSION_free(ext);
+    for (i = X509_get_ext_count(x509); i > 0; i--)
+        X509_EXTENSION_free(X509_delete_ext(x509, 0));
     for (i=0; i<RARRAY_LEN(ary); i++) {
 	ext = GetX509ExtPtr(RARRAY_AREF(ary, i));
 	if (!X509_add_ext(x509, ext, -1)) { /* DUPs ext */
-	    ossl_raise(eX509CertError, NULL);
+	    ossl_raise(eX509CertError, "X509_add_ext");
 	}
     }
 
diff --git a/ext/openssl/ossl_x509crl.c b/ext/openssl/ossl_x509crl.c
index 863f0286c0..6c1d915370 100644
--- a/ext/openssl/ossl_x509crl.c
+++ b/ext/openssl/ossl_x509crl.c
@@ -474,12 +474,12 @@ ossl_x509crl_set_extensions(VALUE self, VALUE ary)
 	OSSL_Check_Kind(RARRAY_AREF(ary, i), cX509Ext);
     }
     GetX509CRL(self, crl);
-    while ((ext = X509_CRL_delete_ext(crl, 0)))
-	X509_EXTENSION_free(ext);
+    for (i = X509_CRL_get_ext_count(crl); i > 0; i--)
+        X509_EXTENSION_free(X509_CRL_delete_ext(crl, 0));
     for (i=0; i<RARRAY_LEN(ary); i++) {
 	ext = GetX509ExtPtr(RARRAY_AREF(ary, i)); /* NO NEED TO DUP */
 	if (!X509_CRL_add_ext(crl, ext, -1)) {
-	    ossl_raise(eX509CRLError, NULL);
+	    ossl_raise(eX509CRLError, "X509_CRL_add_ext");
 	}
     }
 
diff --git a/ext/openssl/ossl_x509req.c b/ext/openssl/ossl_x509req.c
index 6eb91e9c2f..77a7d3f2ff 100644
--- a/ext/openssl/ossl_x509req.c
+++ b/ext/openssl/ossl_x509req.c
@@ -380,13 +380,13 @@ ossl_x509req_set_attributes(VALUE self, VALUE ary)
 	OSSL_Check_Kind(RARRAY_AREF(ary, i), cX509Attr);
     }
     GetX509Req(self, req);
-    while ((attr = X509_REQ_delete_attr(req, 0)))
-	X509_ATTRIBUTE_free(attr);
+    for (i = X509_REQ_get_attr_count(req); i > 0; i--)
+        X509_ATTRIBUTE_free(X509_REQ_delete_attr(req, 0));
     for (i=0;i<RARRAY_LEN(ary); i++) {
 	item = RARRAY_AREF(ary, i);
 	attr = GetX509AttrPtr(item);
 	if (!X509_REQ_add1_attr(req, attr)) {
-	    ossl_raise(eX509ReqError, NULL);
+	    ossl_raise(eX509ReqError, "X509_REQ_add1_attr");
 	}
     }
     return ary;
diff --git a/ext/openssl/ossl_x509revoked.c b/ext/openssl/ossl_x509revoked.c
index 5fe6853430..10b8aa4ad6 100644
--- a/ext/openssl/ossl_x509revoked.c
+++ b/ext/openssl/ossl_x509revoked.c
@@ -223,13 +223,13 @@ ossl_x509revoked_set_extensions(VALUE self, VALUE ary)
 	OSSL_Check_Kind(RARRAY_AREF(ary, i), cX509Ext);
     }
     GetX509Rev(self, rev);
-    while ((ext = X509_REVOKED_delete_ext(rev, 0)))
-	X509_EXTENSION_free(ext);
+    for (i = X509_REVOKED_get_ext_count(rev); i > 0; i--)
+        X509_EXTENSION_free(X509_REVOKED_delete_ext(rev, 0));
     for (i=0; i<RARRAY_LEN(ary); i++) {
 	item = RARRAY_AREF(ary, i);
 	ext = GetX509ExtPtr(item);
 	if(!X509_REVOKED_add_ext(rev, ext, -1)) {
-	    ossl_raise(eX509RevError, NULL);
+	    ossl_raise(eX509RevError, "X509_REVOKED_add_ext");
 	}
     }
 
diff --git a/ext/pathname/lib/pathname.rb b/ext/pathname/lib/pathname.rb
index 3799d589d5..7bdfd0eb39 100644
--- a/ext/pathname/lib/pathname.rb
+++ b/ext/pathname/lib/pathname.rb
@@ -338,6 +338,8 @@ class Pathname
 
   #
   # Appends a pathname fragment to +self+ to produce a new Pathname object.
+  # Since +other+ is considered as a path relative to +self+, if +other+ is
+  # an absolute path, the new Pathname object is created from just +other+.
   #
   #   p1 = Pathname.new("/usr")      # Pathname:/usr
   #   p2 = p1 + "bin/ruby"           # Pathname:/usr/bin/ruby
@@ -399,6 +401,8 @@ class Pathname
 
   #
   # Joins the given pathnames onto +self+ to create a new Pathname object.
+  # This is effectively the same as using Pathname#+ to append +self+ and
+  # all arguments sequentially.
   #
   #   path0 = Pathname.new("/usr")                # Pathname:/usr
   #   path0 = path0.join("bin/ruby")              # Pathname:/usr/bin/ruby
@@ -574,9 +578,9 @@ class Pathname    # * Find *
 end
 
 
-class Pathname    # * FileUtils *
-  autoload(:FileUtils, 'fileutils')
+autoload(:FileUtils, 'fileutils')
 
+class Pathname    # * FileUtils *
   # Creates a full path, including any intermediate directories that don't yet
   # exist.
   #
@@ -588,11 +592,12 @@ class Pathname    # * FileUtils *
 
   # Recursively deletes a directory, including all directories beneath it.
   #
-  # See FileUtils.rm_r
-  def rmtree
+  # See FileUtils.rm_rf
+  def rmtree(noop: nil, verbose: nil, secure: nil)
     # The name "rmtree" is borrowed from File::Path of Perl.
     # File::Path provides "mkpath" and "rmtree".
-    FileUtils.rm_r(@path)
+    require 'fileutils'
+    FileUtils.rm_rf(@path, noop: noop, verbose: verbose, secure: secure)
     nil
   end
 end
diff --git a/ext/pathname/pathname.c b/ext/pathname/pathname.c
index 00ca85205b..8ee4bcec5b 100644
--- a/ext/pathname/pathname.c
+++ b/ext/pathname/pathname.c
@@ -35,6 +35,7 @@ static ID id_lchmod;
 static ID id_lchown;
 static ID id_link;
 static ID id_lstat;
+static ID id_lutime;
 static ID id_mkdir;
 static ID id_mtime;
 static ID id_open;
@@ -765,6 +766,19 @@ path_utime(VALUE self, VALUE atime, VALUE mtime)
 }
 
 /*
+ * Update the access and modification times of the file.
+ *
+ * Same as Pathname#utime, but does not follow symbolic links.
+ *
+ * See File.lutime.
+ */
+static VALUE
+path_lutime(VALUE self, VALUE atime, VALUE mtime)
+{
+    return rb_funcall(rb_cFile, id_lutime, 3, atime, mtime, get_strpath(self));
+}
+
+/*
  * Returns the last component of the path.
  *
  * See File.basename.
@@ -1212,7 +1226,7 @@ path_entries(VALUE self)
     ary = rb_funcall(rb_cDir, id_entries, 1, str);
     ary = rb_convert_type(ary, T_ARRAY, "Array", "to_ary");
     for (i = 0; i < RARRAY_LEN(ary); i++) {
-	VALUE elt = RARRAY_AREF(ary, i);
+        VALUE elt = RARRAY_AREF(ary, i);
         elt = rb_class_new_instance(1, &elt, klass);
         rb_ary_store(ary, i, elt);
     }
@@ -1465,6 +1479,7 @@ path_f_pathname(VALUE self, VALUE str)
  * - #make_symlink(old)
  * - #truncate(length)
  * - #utime(atime, mtime)
+ * - #lutime(atime, mtime)
  * - #basename(*args)
  * - #dirname
  * - #extname
@@ -1563,6 +1578,7 @@ Init_pathname(void)
     rb_define_method(rb_cPathname, "make_symlink", path_make_symlink, 1);
     rb_define_method(rb_cPathname, "truncate", path_truncate, 1);
     rb_define_method(rb_cPathname, "utime", path_utime, 2);
+    rb_define_method(rb_cPathname, "lutime", path_lutime, 2);
     rb_define_method(rb_cPathname, "basename", path_basename, -1);
     rb_define_method(rb_cPathname, "dirname", path_dirname, 0);
     rb_define_method(rb_cPathname, "extname", path_extname, 0);
@@ -1646,6 +1662,7 @@ InitVM_pathname(void)
     id_lchown = rb_intern("lchown");
     id_link = rb_intern("link");
     id_lstat = rb_intern("lstat");
+    id_lutime = rb_intern("lutime");
     id_mkdir = rb_intern("mkdir");
     id_mtime = rb_intern("mtime");
     id_open = rb_intern("open");
diff --git a/ext/pathname/pathname.gemspec b/ext/pathname/pathname.gemspec
index c9c0b84e69..92bc02b0db 100644
--- a/ext/pathname/pathname.gemspec
+++ b/ext/pathname/pathname.gemspec
@@ -1,6 +1,6 @@
 Gem::Specification.new do |spec|
   spec.name          = "pathname"
-  spec.version       = "0.2.0"
+  spec.version       = "0.2.1"
   spec.authors       = ["Tanaka Akira"]
   spec.email         = ["akr@fsij.org"]
 
diff --git a/ext/psych/extconf.rb b/ext/psych/extconf.rb
index b9cd12033d..41daf8c238 100644
--- a/ext/psych/extconf.rb
+++ b/ext/psych/extconf.rb
@@ -6,37 +6,9 @@ if $mswin or $mingw or $cygwin
   $CPPFLAGS << " -DYAML_DECLARE_STATIC"
 end
 
-yaml_source = with_config("libyaml-source-dir") || enable_config("bundled-libyaml", false)
-unless yaml_source # default to pre-installed libyaml
-  pkg_config('yaml-0.1')
-  dir_config('libyaml')
-  unless find_header('yaml.h') && find_library('yaml', 'yaml_get_version')
-    yaml_source = true # fallback to the bundled source if exists
-  end
-end
-
-if yaml_source == true
-  # search the latest libyaml source under $srcdir
-  yaml_source = Dir.glob("#{$srcdir}/yaml{,-*}/").max_by {|n| File.basename(n).scan(/\d+/).map(&:to_i)}
-  unless yaml_source
-    download_failure = "failed to download libyaml source"
-    begin
-      require_relative '../../tool/extlibs.rb'
-      extlibs = ExtLibs.new(cache_dir: File.expand_path("../../tmp/download_cache", $srcdir))
-      unless extlibs.process_under($srcdir)
-        raise download_failure
-      end
-    rescue
-      # Implicitly captures Exception#cause. Newer rubies show it in the backtrace.
-      raise download_failure
-    end
-    yaml_source, = Dir.glob("#{$srcdir}/yaml-*/")
-    raise "libyaml not found" unless yaml_source
-  end
-elsif yaml_source
-  yaml_source = yaml_source.gsub(/\$\((\w+)\)|\$\{(\w+)\}/) {ENV[$1||$2]}
-end
+yaml_source = with_config("libyaml-source-dir")
 if yaml_source
+  yaml_source = yaml_source.gsub(/\$\((\w+)\)|\$\{(\w+)\}/) {ENV[$1||$2]}
   yaml_source = yaml_source.chomp("/")
   yaml_configure = "#{File.expand_path(yaml_source)}/configure"
   unless File.exist?(yaml_configure)
@@ -64,6 +36,11 @@ if yaml_source
   libyaml = "libyaml.#$LIBEXT"
   $cleanfiles << libyaml
   $LOCAL_LIBS.prepend("$(LIBYAML) ")
+else # default to pre-installed libyaml
+  pkg_config('yaml-0.1')
+  dir_config('libyaml')
+  find_header('yaml.h') or abort "yaml.h not found"
+  find_library('yaml', 'yaml_get_version') or abort "libyaml not found"
 end
 
 create_makefile 'psych' do |mk|
diff --git a/ext/psych/extlibs b/ext/psych/extlibs
deleted file mode 100644
index 108aad42af..0000000000
--- a/ext/psych/extlibs
+++ /dev/null
@@ -1,11 +0,0 @@
-ver = 0.2.5
-pkg = yaml-$(ver)
-
-https://github.com/yaml/libyaml/releases/download/$(ver)/$(pkg).tar.gz \
-	rmd160:cc175ed640046722fb7790de828002633407b6b9 \
-	sha256:c642ae9b75fee120b2d96c712538bd2cf283228d2337df2cf2988e3c02678ef4 \
-	sha512:dadd7d8e0d88b5ebab005e5d521d56d541580198aa497370966b98c904586e642a1cd4f3881094eb57624f218d50db77417bbfd0ffdce50340f011e35e8c4c02 \
-	#
-
-$(pkg)/config/config.guess -> /tool/config.guess
-$(pkg)/config/config.sub -> /tool/config.sub
diff --git a/ext/psych/lib/psych.rb b/ext/psych/lib/psych.rb
index 42d79efb83..4a2ab58514 100644
--- a/ext/psych/lib/psych.rb
+++ b/ext/psych/lib/psych.rb
@@ -307,7 +307,7 @@ module Psych
   # A Psych::DisallowedClass exception will be raised if the yaml contains a
   # class that isn't in the +permitted_classes+ list.
   #
-  # A Psych::BadAlias exception will be raised if the yaml contains aliases
+  # A Psych::AliasesNotEnabled exception will be raised if the yaml contains aliases
   # but the +aliases+ keyword argument is set to false.
   #
   # +filename+ will be used in the exception message if any exception is raised
diff --git a/ext/psych/lib/psych/exception.rb b/ext/psych/lib/psych/exception.rb
index f473b95a3b..d7469a4b30 100644
--- a/ext/psych/lib/psych/exception.rb
+++ b/ext/psych/lib/psych/exception.rb
@@ -6,6 +6,20 @@ module Psych
   class BadAlias < Exception
   end
 
+  # Subclasses `BadAlias` for backwards compatibility
+  class AliasesNotEnabled < BadAlias
+    def initialize
+      super "Alias parsing was not enabled. To enable it, pass `aliases: true` to `Psych::load` or `Psych::safe_load`."
+    end
+  end
+
+  # Subclasses `BadAlias` for backwards compatibility
+  class AnchorNotDefined < BadAlias
+    def initialize anchor_name
+      super "An alias referenced an unknown anchor: #{anchor_name}"
+    end
+  end
+
   class DisallowedClass < Exception
     def initialize action, klass_name
       super "Tried to #{action} unspecified class: #{klass_name}"
diff --git a/ext/psych/lib/psych/parser.rb b/ext/psych/lib/psych/parser.rb
index 39bc8289be..2181c730e5 100644
--- a/ext/psych/lib/psych/parser.rb
+++ b/ext/psych/lib/psych/parser.rb
@@ -48,5 +48,18 @@ module Psych
       @handler = handler
       @external_encoding = ANY
     end
+
+    ###
+    # call-seq:
+    #    parser.parse(yaml)
+    #
+    # Parse the YAML document contained in +yaml+.  Events will be called on
+    # the handler set on the parser instance.
+    #
+    # See Psych::Parser and Psych::Parser#handler
+
+    def parse yaml, path = yaml.respond_to?(:path) ? yaml.path : "<unknown>"
+      _native_parse @handler, yaml, path
+    end
   end
 end
diff --git a/ext/psych/lib/psych/scalar_scanner.rb b/ext/psych/lib/psych/scalar_scanner.rb
index 58deea3baa..3cb4bf3c7e 100644
--- a/ext/psych/lib/psych/scalar_scanner.rb
+++ b/ext/psych/lib/psych/scalar_scanner.rb
@@ -63,7 +63,7 @@ module Psych
       elsif string.match?(/^\d{4}-(?:1[012]|0\d|\d)-(?:[12]\d|3[01]|0\d|\d)$/)
         require 'date'
         begin
-          class_loader.date.strptime(string, '%Y-%m-%d')
+          class_loader.date.strptime(string, '%F', Date::GREGORIAN)
         rescue ArgumentError
           string
         end
@@ -95,7 +95,7 @@ module Psych
         if string.match?(/\A[-+]?\.\Z/)
           string
         else
-          Float(string.gsub(/[,_]|\.([Ee]|$)/, '\1'))
+          Float(string.delete(',_').gsub(/\.([Ee]|$)/, '\1'))
         end
       elsif string.match?(integer_regex)
         parse_int string
@@ -107,7 +107,7 @@ module Psych
     ###
     # Parse and return an int from +string+
     def parse_int string
-      Integer(string.gsub(/[,_]/, ''))
+      Integer(string.delete(',_'))
     end
 
     ###
diff --git a/ext/psych/lib/psych/versions.rb b/ext/psych/lib/psych/versions.rb
index 3cfd59e751..a592a6916c 100644
--- a/ext/psych/lib/psych/versions.rb
+++ b/ext/psych/lib/psych/versions.rb
@@ -2,9 +2,9 @@
 
 module Psych
   # The version of Psych you are using
-  VERSION = '4.0.3'
+  VERSION = '5.0.1'
 
   if RUBY_ENGINE == 'jruby'
-    DEFAULT_SNAKEYAML_VERSION = '1.28'.freeze
+    DEFAULT_SNAKEYAML_VERSION = '1.33'.freeze
   end
 end
diff --git a/ext/psych/lib/psych/visitors/to_ruby.rb b/ext/psych/lib/psych/visitors/to_ruby.rb
index 935bc74f21..8614251ca9 100644
--- a/ext/psych/lib/psych/visitors/to_ruby.rb
+++ b/ext/psych/lib/psych/visitors/to_ruby.rb
@@ -80,7 +80,9 @@ module Psych
         when "!ruby/object:DateTime"
           class_loader.date_time
           require 'date' unless defined? DateTime
-          @ss.parse_time(o.value).to_datetime
+          t = @ss.parse_time(o.value)
+          DateTime.civil(*t.to_a[0, 6].reverse, Rational(t.utc_offset, 86400)) +
+            (t.subsec/86400)
         when '!ruby/encoding'
           ::Encoding.find o.value
         when "!ruby/object:Complex"
@@ -323,7 +325,7 @@ module Psych
       end
 
       def visit_Psych_Nodes_Alias o
-        @st.fetch(o.anchor) { raise BadAlias, "Unknown alias: #{o.anchor}" }
+        @st.fetch(o.anchor) { raise AnchorNotDefined, o.anchor }
       end
 
       private
@@ -427,7 +429,7 @@ module Psych
 
     class NoAliasRuby < ToRuby
       def visit_Psych_Nodes_Alias o
-        raise BadAlias, "Unknown alias: #{o.anchor}"
+        raise AliasesNotEnabled
       end
     end
   end
diff --git a/ext/psych/lib/psych/visitors/yaml_tree.rb b/ext/psych/lib/psych/visitors/yaml_tree.rb
index 316a3a9496..31858798e4 100644
--- a/ext/psych/lib/psych/visitors/yaml_tree.rb
+++ b/ext/psych/lib/psych/visitors/yaml_tree.rb
@@ -192,12 +192,13 @@ module Psych
         register o, @emitter.scalar(o.inspect, nil, '!ruby/regexp', false, false, Nodes::Scalar::ANY)
       end
 
+      def visit_Date o
+        register o, visit_Integer(o.gregorian)
+      end
+
       def visit_DateTime o
-        formatted = if o.offset.zero?
-                      o.strftime("%Y-%m-%d %H:%M:%S.%9N Z".freeze)
-                    else
-                      o.strftime("%Y-%m-%d %H:%M:%S.%9N %:z".freeze)
-                    end
+        t = o.italy
+        formatted = format_time t, t.offset.zero?
         tag = '!ruby/object:DateTime'
         register o, @emitter.scalar(formatted, nil, tag, false, false, Nodes::Scalar::ANY)
       end
@@ -235,7 +236,6 @@ module Psych
       end
       alias :visit_TrueClass :visit_Integer
       alias :visit_FalseClass :visit_Integer
-      alias :visit_Date :visit_Integer
 
       def visit_Float o
         if o.nan?
@@ -482,8 +482,8 @@ module Psych
         @emitter.end_mapping
       end
 
-      def format_time time
-        if time.utc?
+      def format_time time, utc = time.utc?
+        if utc
           time.strftime("%Y-%m-%d %H:%M:%S.%9N Z")
         else
           time.strftime("%Y-%m-%d %H:%M:%S.%9N %:z")
diff --git a/ext/psych/psych_parser.c b/ext/psych/psych_parser.c
index fd550b671a..9c5179cc44 100644
--- a/ext/psych/psych_parser.c
+++ b/ext/psych/psych_parser.c
@@ -79,21 +79,25 @@ static VALUE allocate(VALUE klass)
 
 static VALUE make_exception(yaml_parser_t * parser, VALUE path)
 {
-    size_t line, column;
-    VALUE ePsychSyntaxError;
+    if (parser->error == YAML_MEMORY_ERROR) {
+	return rb_eNoMemError;
+    } else {
+	size_t line, column;
+	VALUE ePsychSyntaxError;
 
-    line = parser->context_mark.line + 1;
-    column = parser->context_mark.column + 1;
+	line = parser->context_mark.line + 1;
+	column = parser->context_mark.column + 1;
 
-    ePsychSyntaxError = rb_const_get(mPsych, rb_intern("SyntaxError"));
+	ePsychSyntaxError = rb_const_get(mPsych, rb_intern("SyntaxError"));
 
-    return rb_funcall(ePsychSyntaxError, rb_intern("new"), 6,
-	    path,
-	    SIZET2NUM(line),
-	    SIZET2NUM(column),
-	    SIZET2NUM(parser->problem_offset),
-	    parser->problem ? rb_usascii_str_new2(parser->problem) : Qnil,
-	    parser->context ? rb_usascii_str_new2(parser->context) : Qnil);
+	return rb_funcall(ePsychSyntaxError, rb_intern("new"), 6,
+		path,
+		SIZET2NUM(line),
+		SIZET2NUM(column),
+		SIZET2NUM(parser->problem_offset),
+		parser->problem ? rb_usascii_str_new2(parser->problem) : Qnil,
+		parser->context ? rb_usascii_str_new2(parser->context) : Qnil);
+    }
 }
 
 static VALUE transcode_string(VALUE src, int * parser_encoding)
@@ -241,18 +245,8 @@ static VALUE protected_event_location(VALUE pointer)
     return rb_funcall3(args[0], id_event_location, 4, args + 1);
 }
 
-/*
- * call-seq:
- *    parser.parse(yaml)
- *
- * Parse the YAML document contained in +yaml+.  Events will be called on
- * the handler set on the parser instance.
- *
- * See Psych::Parser and Psych::Parser#handler
- */
-static VALUE parse(int argc, VALUE *argv, VALUE self)
+static VALUE parse(VALUE self, VALUE handler, VALUE yaml, VALUE path)
 {
-    VALUE yaml, path;
     yaml_parser_t * parser;
     yaml_event_t event;
     int done = 0;
@@ -260,14 +254,6 @@ static VALUE parse(int argc, VALUE *argv, VALUE self)
     int parser_encoding = YAML_ANY_ENCODING;
     int encoding = rb_utf8_encindex();
     rb_encoding * internal_enc = rb_default_internal_encoding();
-    VALUE handler = rb_iv_get(self, "@handler");
-
-    if (rb_scan_args(argc, argv, "11", &yaml, &path) == 1) {
-	if(rb_respond_to(yaml, id_path))
-	    path = rb_funcall(yaml, id_path, 0);
-	else
-	    path = rb_str_new2("<unknown>");
-    }
 
     TypedData_Get_Struct(self, yaml_parser_t, &psych_parser_type, parser);
 
@@ -293,7 +279,7 @@ static VALUE parse(int argc, VALUE *argv, VALUE self)
 	VALUE event_args[5];
 	VALUE start_line, start_column, end_line, end_column;
 
-	if(!yaml_parser_parse(parser, &event)) {
+	if(parser->error || !yaml_parser_parse(parser, &event)) {
 	    VALUE exception;
 
 	    exception = make_exception(parser, path);
@@ -558,7 +544,7 @@ void Init_psych_parser(void)
 
     rb_require("psych/syntax_error");
 
-    rb_define_method(cPsychParser, "parse", parse, -1);
+    rb_define_private_method(cPsychParser, "_native_parse", parse, 3);
     rb_define_method(cPsychParser, "mark", mark, 0);
 
     id_read            = rb_intern("read");
diff --git a/ext/pty/depend b/ext/pty/depend
index c43d3dcf9a..f251caae3f 100644
--- a/ext/pty/depend
+++ b/ext/pty/depend
@@ -181,5 +181,6 @@ pty.o: $(top_srcdir)/internal/process.h
 pty.o: $(top_srcdir)/internal/signal.h
 pty.o: $(top_srcdir)/internal/static_assert.h
 pty.o: $(top_srcdir)/internal/warnings.h
+pty.o: $(top_srcdir)/shape.h
 pty.o: pty.c
 # AUTOGENERATED DEPENDENCIES END
diff --git a/ext/pty/extconf.rb b/ext/pty/extconf.rb
index 038bdf4d2c..ba0c4286fd 100644
--- a/ext/pty/extconf.rb
+++ b/ext/pty/extconf.rb
@@ -7,10 +7,12 @@ if /mswin|mingw|bccwin/ !~ RUBY_PLATFORM
   have_header("sys/stropts.h")
   have_func("setresuid")
   have_header("libutil.h")
-  have_header("util.h") # OpenBSD openpty
   have_header("pty.h")
   have_header("pwd.h")
-  util = have_library("util", "openpty")
+  if /openbsd/ =~ RUBY_PLATFORM
+    have_header("util.h") # OpenBSD openpty
+    util = have_library("util", "openpty")
+  end
   if have_func("posix_openpt") or
       (util or have_func("openpty")) or
       have_func("_getpty") or
diff --git a/ext/pty/lib/expect.rb b/ext/pty/lib/expect.rb
index 5dbfa09ae9..22cbf54115 100644
--- a/ext/pty/lib/expect.rb
+++ b/ext/pty/lib/expect.rb
@@ -1,19 +1,19 @@
 # frozen_string_literal: true
 $expect_verbose = false
 
-# Expect library adds the IO instance method #expect, which does similar act to
-# tcl's expect extension.
-#
-# In order to use this method, you must require expect:
-#
-#   require 'expect'
-#
-# Please see #expect for usage.
 class IO
   # call-seq:
   #   IO#expect(pattern,timeout=9999999)                  ->  Array
   #   IO#expect(pattern,timeout=9999999) { |result| ... } ->  nil
   #
+  # The +expect+ library adds instance method IO#expect,
+  # which is similar to the
+  # {TCL expect extension}[https://www.tcl.tk/man/expect5.31/expect.1.html].
+  #
+  # To use this method, you must require +expect+:
+  #
+  #   require 'expect'
+  #
   # Reads from the IO until the given +pattern+ matches or the +timeout+ is over.
   #
   # It returns an array with the read buffer, followed by the matches.
diff --git a/ext/pty/pty.c b/ext/pty/pty.c
index cb663ab2de..acec33f9bf 100644
--- a/ext/pty/pty.c
+++ b/ext/pty/pty.c
@@ -107,8 +107,8 @@ chfunc(void *data, char *errbuf, size_t errbuf_len)
     int slave = carg->slave;
 
 #define ERROR_EXIT(str) do { \
-	strlcpy(errbuf, (str), errbuf_len); \
-	return -1; \
+        strlcpy(errbuf, (str), errbuf_len); \
+        return -1; \
     } while (0)
 
     /*
@@ -166,32 +166,32 @@ chfunc(void *data, char *errbuf, size_t errbuf_len)
 
 static void
 establishShell(int argc, VALUE *argv, struct pty_info *info,
-	       char SlaveName[DEVICELEN])
+               char SlaveName[DEVICELEN])
 {
     int 		master, slave, status = 0;
     rb_pid_t		pid;
-    char		*p, *getenv();
+    char		*p;
     VALUE		v;
     struct child_info   carg;
     char		errbuf[32];
 
     if (argc == 0) {
-	const char *shellname = "/bin/sh";
+        const char *shellname = "/bin/sh";
 
-	if ((p = getenv("SHELL")) != NULL) {
-	    shellname = p;
-	}
-	else {
+        if ((p = getenv("SHELL")) != NULL) {
+            shellname = p;
+        }
+        else {
 #if defined HAVE_PWD_H
-	    const char *username = getenv("USER");
-	    struct passwd *pwent = getpwnam(username ? username : getlogin());
-	    if (pwent && pwent->pw_shell)
-		shellname = pwent->pw_shell;
+            const char *username = getenv("USER");
+            struct passwd *pwent = getpwnam(username ? username : getlogin());
+            if (pwent && pwent->pw_shell)
+                shellname = pwent->pw_shell;
 #endif
-	}
-	v = rb_str_new2(shellname);
-	argc = 1;
-	argv = &v;
+        }
+        v = rb_str_new2(shellname);
+        argc = 1;
+        argv = &v;
     }
 
     carg.execarg_obj = rb_execarg_new(argc, argv, 1, 0);
@@ -207,13 +207,13 @@ establishShell(int argc, VALUE *argv, struct pty_info *info,
     pid = rb_fork_async_signal_safe(&status, chfunc, &carg, Qnil, errbuf, sizeof(errbuf));
 
     if (pid < 0) {
-	int e = errno;
-	close(master);
-	close(slave);
+        int e = errno;
+        close(master);
+        close(slave);
         rb_execarg_parent_end(carg.execarg_obj);
-	errno = e;
-	if (status) rb_jump_tag(status);
-	rb_sys_fail(errbuf[0] ? errbuf : "fork failed");
+        errno = e;
+        if (status) rb_jump_tag(status);
+        rb_sys_fail(errbuf[0] ? errbuf : "fork failed");
     }
 
     close(slave);
@@ -268,14 +268,14 @@ get_device_once(int *master, int *slave, char SlaveName[DEVICELEN], int nomesg,
     rb_fd_fix_cloexec(masterfd);
 #else
     {
-	int flags = O_RDWR|O_NOCTTY;
+        int flags = O_RDWR|O_NOCTTY;
 # if defined(O_CLOEXEC)
-	/* glibc posix_openpt() in GNU/Linux calls open("/dev/ptmx", flags) internally.
-	 * So version dependency on GNU/Linux is the same as O_CLOEXEC with open().
-	 * O_CLOEXEC is available since Linux 2.6.23.  Linux 2.6.18 silently ignore it. */
-	flags |= O_CLOEXEC;
+        /* glibc posix_openpt() in GNU/Linux calls open("/dev/ptmx", flags) internally.
+         * So version dependency on GNU/Linux is the same as O_CLOEXEC with open().
+         * O_CLOEXEC is available since Linux 2.6.23.  Linux 2.6.18 silently ignore it. */
+        flags |= O_CLOEXEC;
 # endif
-	if ((masterfd = posix_openpt(flags)) == -1) goto error;
+        if ((masterfd = posix_openpt(flags)) == -1) goto error;
     }
     rb_fd_fix_cloexec(masterfd);
     if (rb_grantpt(masterfd) == -1) goto error;
@@ -310,15 +310,15 @@ get_device_once(int *master, int *slave, char SlaveName[DEVICELEN], int nomesg,
  * or the same interface function.
  */
     if (openpty(master, slave, SlaveName,
-		(struct termios *)0, (struct winsize *)0) == -1) {
-	if (!fail) return -1;
-	rb_raise(rb_eRuntimeError, "openpty() failed");
+                (struct termios *)0, (struct winsize *)0) == -1) {
+        if (!fail) return -1;
+        rb_raise(rb_eRuntimeError, "openpty() failed");
     }
     rb_fd_fix_cloexec(*master);
     rb_fd_fix_cloexec(*slave);
     if (no_mesg(SlaveName, nomesg) == -1) {
-	if (!fail) return -1;
-	rb_raise(rb_eRuntimeError, "can't chmod slave pty");
+        if (!fail) return -1;
+        rb_raise(rb_eRuntimeError, "can't chmod slave pty");
     }
 
     return 0;
@@ -329,8 +329,8 @@ get_device_once(int *master, int *slave, char SlaveName[DEVICELEN], int nomesg,
     mode_t mode = nomesg ? 0600 : 0622;
 
     if (!(name = _getpty(master, O_RDWR, mode, 0))) {
-	if (!fail) return -1;
-	rb_raise(rb_eRuntimeError, "_getpty() failed");
+        if (!fail) return -1;
+        rb_raise(rb_eRuntimeError, "_getpty() failed");
     }
     rb_fd_fix_cloexec(*master);
 
@@ -386,42 +386,42 @@ get_device_once(int *master, int *slave, char SlaveName[DEVICELEN], int nomesg,
     char MasterName[DEVICELEN];
 
 #define HEX1(c) \
-	c"0",c"1",c"2",c"3",c"4",c"5",c"6",c"7", \
-	c"8",c"9",c"a",c"b",c"c",c"d",c"e",c"f"
+        c"0",c"1",c"2",c"3",c"4",c"5",c"6",c"7", \
+        c"8",c"9",c"a",c"b",c"c",c"d",c"e",c"f"
 
 #if defined(_IBMESA)  /* AIX/ESA */
     static const char MasterDevice[] = "/dev/ptyp%s";
     static const char SlaveDevice[] = "/dev/ttyp%s";
     static const char deviceNo[][3] = {
-	HEX1("0"), HEX1("1"), HEX1("2"), HEX1("3"),
-	HEX1("4"), HEX1("5"), HEX1("6"), HEX1("7"),
-	HEX1("8"), HEX1("9"), HEX1("a"), HEX1("b"),
-	HEX1("c"), HEX1("d"), HEX1("e"), HEX1("f"),
+        HEX1("0"), HEX1("1"), HEX1("2"), HEX1("3"),
+        HEX1("4"), HEX1("5"), HEX1("6"), HEX1("7"),
+        HEX1("8"), HEX1("9"), HEX1("a"), HEX1("b"),
+        HEX1("c"), HEX1("d"), HEX1("e"), HEX1("f"),
     };
 #else /* 4.2BSD */
     static const char MasterDevice[] = "/dev/pty%s";
     static const char SlaveDevice[] = "/dev/tty%s";
     static const char deviceNo[][3] = {
-	HEX1("p"), HEX1("q"), HEX1("r"), HEX1("s"),
+        HEX1("p"), HEX1("q"), HEX1("r"), HEX1("s"),
     };
 #endif
 #undef HEX1
     for (i = 0; i < numberof(deviceNo); i++) {
-	const char *const devno = deviceNo[i];
-	snprintf(MasterName, sizeof MasterName, MasterDevice, devno);
-	if ((masterfd = rb_cloexec_open(MasterName,O_RDWR,0)) >= 0) {
+        const char *const devno = deviceNo[i];
+        snprintf(MasterName, sizeof MasterName, MasterDevice, devno);
+        if ((masterfd = rb_cloexec_open(MasterName,O_RDWR,0)) >= 0) {
             rb_update_max_fd(masterfd);
-	    *master = masterfd;
-	    snprintf(SlaveName, DEVICELEN, SlaveDevice, devno);
-	    if ((slavefd = rb_cloexec_open(SlaveName,O_RDWR,0)) >= 0) {
+            *master = masterfd;
+            snprintf(SlaveName, DEVICELEN, SlaveDevice, devno);
+            if ((slavefd = rb_cloexec_open(SlaveName,O_RDWR,0)) >= 0) {
                 rb_update_max_fd(slavefd);
-		*slave = slavefd;
-		if (chown(SlaveName, getuid(), getgid()) != 0) goto error;
-		if (chmod(SlaveName, nomesg ? 0600 : 0622) != 0) goto error;
-		return 0;
-	    }
-	    close(masterfd);
-	}
+                *slave = slavefd;
+                if (chown(SlaveName, getuid(), getgid()) != 0) goto error;
+                if (chmod(SlaveName, nomesg ? 0600 : 0622) != 0) goto error;
+                return 0;
+            }
+            close(masterfd);
+        }
     }
   error:
     if (slavefd != -1) close(slavefd);
@@ -435,8 +435,8 @@ static void
 getDevice(int *master, int *slave, char SlaveName[DEVICELEN], int nomesg)
 {
     if (get_device_once(master, slave, SlaveName, nomesg, 0)) {
-	rb_gc();
-	get_device_once(master, slave, SlaveName, nomesg, 1);
+        rb_gc();
+        get_device_once(master, slave, SlaveName, nomesg, 1);
     }
 }
 
@@ -519,7 +519,7 @@ pty_open(VALUE klass)
 
     assoc = rb_assoc_new(master_io, slave_file);
     if (rb_block_given_p()) {
-	return rb_ensure(rb_yield, assoc, pty_close_pty, assoc);
+        return rb_ensure(rb_yield, assoc, pty_close_pty, assoc);
     }
     return assoc;
 }
@@ -531,7 +531,7 @@ pty_detach_process(VALUE v)
 #ifdef WNOHANG
     int st;
     if (rb_waitpid(info->child_pid, &st, WNOHANG) <= 0)
-	return Qnil;
+        return Qnil;
 #endif
     rb_detach_process(info->child_pid);
     return Qnil;
@@ -539,10 +539,10 @@ pty_detach_process(VALUE v)
 
 /*
  * call-seq:
- *   PTY.spawn(command_line)  { |r, w, pid| ... }
- *   PTY.spawn(command_line)  => [r, w, pid]
- *   PTY.spawn(command, arguments, ...)  { |r, w, pid| ... }
- *   PTY.spawn(command, arguments, ...)  => [r, w, pid]
+ *   PTY.spawn([env,] command_line)  { |r, w, pid| ... }
+ *   PTY.spawn([env,] command_line)  => [r, w, pid]
+ *   PTY.spawn([env,] command, arguments, ...)  { |r, w, pid| ... }
+ *   PTY.spawn([env,] command, arguments, ...)  => [r, w, pid]
  *
  * Spawns the specified command on a newly allocated pty. You can also use the
  * alias ::getpty.
@@ -550,6 +550,13 @@ pty_detach_process(VALUE v)
  * The command's controlling tty is set to the slave device of the pty
  * and its standard input/output/error is redirected to the slave device.
  *
+ * +env+ is an optional hash that provides additional environment variables to the spawned pty.
+ *
+ *   # sets FOO to "bar"
+ *   PTY.spawn({"FOO"=>"bar"}, "printenv", "FOO") { |r,w,pid| p r.read } #=> "bar\r\n"
+ *   # unsets FOO
+ *   PTY.spawn({"FOO"=>nil}, "printenv", "FOO") { |r,w,pid| p r.read } #=> ""
+ *
  * +command+ and +command_line+ are the full commands to run, given a String.
  * Any additional +arguments+ will be passed to the command.
  *
@@ -597,8 +604,8 @@ pty_getpty(int argc, VALUE *argv, VALUE self)
     rb_ary_store(res,2,PIDT2NUM(info.child_pid));
 
     if (rb_block_given_p()) {
-	rb_ensure(rb_yield, res, pty_detach_process, (VALUE)&info);
-	return Qnil;
+        rb_ensure(rb_yield, res, pty_detach_process, (VALUE)&info);
+        return Qnil;
     }
     return res;
 }
@@ -618,13 +625,13 @@ raise_from_check(rb_pid_t pid, int status)
 ---->> Either IF_STOPPED or WIFSTOPPED is needed <<----
 #endif /* WIFSTOPPED | IF_STOPPED */
     if (WIFSTOPPED(status)) { /* suspend */
-	state = "stopped";
+        state = "stopped";
     }
     else if (kill(pid, 0) == 0) {
-	state = "changed";
+        state = "changed";
     }
     else {
-	state = "exited";
+        state = "exited";
     }
     msg = rb_sprintf("pty - %s: %ld", state, (long)pid);
     exc = rb_exc_new_str(eChildExited, msg);
@@ -657,12 +664,12 @@ pty_check(int argc, VALUE *argv, VALUE self)
     int status;
     const int flag =
 #ifdef WNOHANG
-	WNOHANG|
+        WNOHANG|
 #endif
 #ifdef WUNTRACED
-	WUNTRACED|
+        WUNTRACED|
 #endif
-	0;
+        0;
 
     rb_scan_args(argc, argv, "11", &pid, &exc);
     cpid = rb_waitpid(NUM2PIDT(pid), &status, flag);
diff --git a/ext/racc/cparse/cparse.c b/ext/racc/cparse/cparse.c
index f71ed2bba9..f752eb7749 100644
--- a/ext/racc/cparse/cparse.c
+++ b/ext/racc/cparse/cparse.c
@@ -7,8 +7,6 @@
     This library is free software.
     You can distribute/modify this program under the same terms of ruby.
 
-    $originalId: cparse.c,v 1.8 2006/07/06 11:39:46 aamine Exp $
-
 */
 
 #include <ruby.h>
@@ -24,7 +22,7 @@
                         Important Constants
 ----------------------------------------------------------------------- */
 
-#define RACC_VERSION "1.4.15"
+#define RACC_VERSION "1.6.2"
 
 #define DEFAULT_TOKEN -1
 #define ERROR_TOKEN    1
diff --git a/ext/readline/readline-ext.gemspec b/ext/readline/readline-ext.gemspec
index 0c6f70ba91..1e16edbfe6 100644
--- a/ext/readline/readline-ext.gemspec
+++ b/ext/readline/readline-ext.gemspec
@@ -1,6 +1,6 @@
 Gem::Specification.new do |spec|
   spec.name          = "readline-ext"
-  spec.version       = "0.1.4"
+  spec.version       = "0.1.5"
   spec.authors       = ["Yukihiro Matsumoto"]
   spec.email         = ["matz@ruby-lang.org"]
 
diff --git a/ext/readline/readline.c b/ext/readline/readline.c
index 5ae037dd41..fc254ce315 100644
--- a/ext/readline/readline.c
+++ b/ext/readline/readline.c
@@ -376,8 +376,8 @@ prepare_readline(void)
 {
     static int initialized = 0;
     if (!initialized) {
-	rl_initialize();
-	initialized = 1;
+        rl_initialize();
+        initialized = 1;
     }
 
     if (readline_instream) {
diff --git a/ext/ripper/depend b/ext/ripper/depend
index 80a6d62346..856283e177 100644
--- a/ext/ripper/depend
+++ b/ext/ripper/depend
@@ -17,12 +17,9 @@ ripper.o: ripper.c
 all: check
 static: check
 
-ripper.y: $(srcdir)/tools/preproc.rb $(srcdir)/tools/dsl.rb $(top_srcdir)/parse.y {$(VPATH)}id.h
+ripper.y: $(srcdir)/tools/preproc.rb $(srcdir)/tools/dsl.rb $(top_srcdir)/parse.y $(top_srcdir)/defs/id.def
 	$(ECHO) extracting $@ from $(top_srcdir)/parse.y
-	$(Q) $(RUBY) $(top_srcdir)/tool/id2token.rb --path-separator=.$(PATH_SEPARATOR)./ \
-		--vpath=$(VPATH)$(PATH_SEPARATOR)$(top_srcdir) id.h $(top_srcdir)/parse.y > ripper.tmp.y
-	$(Q) $(RUBY) $(top_srcdir)/tool/pure_parser.rb ripper.tmp.y $(BISON)
-	$(Q) $(RM) ripper.tmp.y.bak
+	$(Q) $(RUBY) $(top_srcdir)/tool/id2token.rb $(top_srcdir)/parse.y > ripper.tmp.y
 	$(Q) $(RUBY) $(srcdir)/tools/preproc.rb ripper.tmp.y --output=$@
 	$(Q) $(RM) ripper.tmp.y
 
@@ -234,6 +231,7 @@ ripper.o: $(top_srcdir)/internal/bits.h
 ripper.o: $(top_srcdir)/internal/compile.h
 ripper.o: $(top_srcdir)/internal/compilers.h
 ripper.o: $(top_srcdir)/internal/complex.h
+ripper.o: $(top_srcdir)/internal/encoding.h
 ripper.o: $(top_srcdir)/internal/error.h
 ripper.o: $(top_srcdir)/internal/fixnum.h
 ripper.o: $(top_srcdir)/internal/gc.h
@@ -255,6 +253,7 @@ ripper.o: $(top_srcdir)/internal/warnings.h
 ripper.o: $(top_srcdir)/node.h
 ripper.o: $(top_srcdir)/regenc.h
 ripper.o: $(top_srcdir)/ruby_assert.h
+ripper.o: $(top_srcdir)/shape.h
 ripper.o: $(top_srcdir)/symbol.h
 ripper.o: ../../probes.h
 ripper.o: eventids2.c
diff --git a/ext/ripper/eventids2.c b/ext/ripper/eventids2.c
index ac38663f2d..05687497ac 100644
--- a/ext/ripper/eventids2.c
+++ b/ext/ripper/eventids2.c
@@ -1,22 +1,3 @@
-enum {
-    tIGNORED_NL  = tLAST_TOKEN + 1,
-# define tIGNORED_NL ((enum yytokentype)tIGNORED_NL)
-    tCOMMENT,
-# define tCOMMENT ((enum yytokentype)tCOMMENT)
-    tEMBDOC_BEG,
-# define tEMBDOC_BEG ((enum yytokentype)tEMBDOC_BEG)
-    tEMBDOC,
-# define tEMBDOC ((enum yytokentype)tEMBDOC)
-    tEMBDOC_END,
-# define tEMBDOC_END ((enum yytokentype)tEMBDOC_END)
-    tHEREDOC_BEG,
-# define tHEREDOC_BEG ((enum yytokentype)tHEREDOC_BEG)
-    tHEREDOC_END,
-# define tHEREDOC_END ((enum yytokentype)tHEREDOC_END)
-    k__END__,
-# define k__END__ ((enum yytokentype)k__END__)
-};
-
 typedef struct {
     ID ripper_id_backref;
     ID ripper_id_backtick;
diff --git a/ext/ripper/lib/ripper/lexer.rb b/ext/ripper/lib/ripper/lexer.rb
index 19c59e2ccc..a0f1cbeaa8 100644
--- a/ext/ripper/lib/ripper/lexer.rb
+++ b/ext/ripper/lib/ripper/lexer.rb
@@ -228,7 +228,7 @@ class Ripper
 
     def on_heredoc_end(tok)
       @buf.push Elem.new([lineno(), column()], __callee__, tok, state())
-      @buf = @stack.pop
+      @buf = @stack.pop unless @stack.empty?
     end
 
     def _push_token(tok)
@@ -242,7 +242,12 @@ class Ripper
     end
 
     def on_error2(mesg, elem)
-      @errors.push Elem.new(elem.pos, __callee__, elem.tok, elem.state, mesg)
+      if elem
+        elem = Elem.new(elem.pos, __callee__, elem.tok, elem.state, mesg)
+      else
+        elem = Elem.new([lineno(), column()], __callee__, token(), state(), mesg)
+      end
+      @errors.push elem
     end
     PARSER_EVENTS.grep(/_error\z/) do |e|
       arity = PARSER_EVENT_TABLE.fetch(e)
diff --git a/ext/ripper/tools/preproc.rb b/ext/ripper/tools/preproc.rb
index b838a78db7..cd85a5da61 100644
--- a/ext/ripper/tools/preproc.rb
+++ b/ext/ripper/tools/preproc.rb
@@ -47,7 +47,7 @@ def prelude(f, out)
     when /\A%%/
       out << "%%\n"
       return
-    when /\A%token/
+    when /\A%token/, /\A} <node>/
       out << line.sub(/<\w+>/, '<val>')
     when /\A%type/
       out << line.sub(/<\w+>/, '<val>')
diff --git a/ext/socket/addrinfo.h b/ext/socket/addrinfo.h
index f0b977d79c..eb9eb8ae0e 100644
--- a/ext/socket/addrinfo.h
+++ b/ext/socket/addrinfo.h
@@ -129,14 +129,14 @@
 
 #ifndef HAVE_TYPE_STRUCT_ADDRINFO
 struct addrinfo {
-	int	ai_flags;	/* AI_PASSIVE, AI_CANONNAME */
-	int	ai_family;	/* PF_xxx */
-	int	ai_socktype;	/* SOCK_xxx */
-	int	ai_protocol;	/* 0 or IPPROTO_xxx for IPv4 and IPv6 */
-	size_t	ai_addrlen;	/* length of ai_addr */
-	char	*ai_canonname;	/* canonical name for hostname */
-	struct sockaddr *ai_addr;	/* binary address */
-	struct addrinfo *ai_next;	/* next structure in linked list */
+        int	ai_flags;	/* AI_PASSIVE, AI_CANONNAME */
+        int	ai_family;	/* PF_xxx */
+        int	ai_socktype;	/* SOCK_xxx */
+        int	ai_protocol;	/* 0 or IPPROTO_xxx for IPv4 and IPv6 */
+        size_t	ai_addrlen;	/* length of ai_addr */
+        char	*ai_canonname;	/* canonical name for hostname */
+        struct sockaddr *ai_addr;	/* binary address */
+        struct addrinfo *ai_next;	/* next structure in linked list */
 };
 #endif
 
@@ -158,18 +158,18 @@ struct addrinfo {
 #endif
 
 extern int getaddrinfo __P((
-	const char *hostname, const char *servname,
-	const struct addrinfo *hints,
-	struct addrinfo **res));
+        const char *hostname, const char *servname,
+        const struct addrinfo *hints,
+        struct addrinfo **res));
 
 extern int getnameinfo __P((
-	const struct sockaddr *sa,
-	socklen_t salen,
-	char *host,
-	socklen_t hostlen,
-	char *serv,
-	socklen_t servlen,
-	int flags));
+        const struct sockaddr *sa,
+        socklen_t salen,
+        char *host,
+        socklen_t hostlen,
+        char *serv,
+        socklen_t servlen,
+        int flags));
 
 extern void freehostent __P((struct hostent *));
 extern void freeaddrinfo __P((struct addrinfo *));
diff --git a/ext/socket/ancdata.c b/ext/socket/ancdata.c
index aa62cab0ec..7406177de2 100644
--- a/ext/socket/ancdata.c
+++ b/ext/socket/ancdata.c
@@ -333,11 +333,11 @@ ancillary_timestamp(VALUE self)
     if (level == SOL_SOCKET && type == SCM_BINTIME &&
         RSTRING_LEN(data) == sizeof(struct bintime)) {
         struct bintime bt;
-	VALUE d, timev;
+        VALUE d, timev;
         memcpy((char*)&bt, RSTRING_PTR(data), sizeof(bt));
-	d = ULL2NUM(0x100000000ULL);
-	d = mul(d,d);
-	timev = add(TIMET2NUM(bt.sec), quo(ULL2NUM(bt.frac), d));
+        d = ULL2NUM(0x100000000ULL);
+        d = mul(d,d);
+        timev = add(TIMET2NUM(bt.sec), quo(ULL2NUM(bt.frac), d));
         result = rb_time_num_new(timev, Qnil);
     }
 # endif
@@ -697,7 +697,7 @@ anc_inspect_passcred_credentials(int level, int type, VALUE data, VALUE ret)
         struct ucred cred;
         memcpy(&cred, RSTRING_PTR(data), sizeof(struct ucred));
         rb_str_catf(ret, " pid=%u uid=%u gid=%u", cred.pid, cred.uid, cred.gid);
-	rb_str_cat2(ret, " (ucred)");
+        rb_str_cat2(ret, " (ucred)");
         return 1;
     }
     else {
@@ -712,7 +712,7 @@ static int
 anc_inspect_socket_creds(int level, int type, VALUE data, VALUE ret)
 {
     if (level != SOL_SOCKET && type != SCM_CREDS)
-	return 0;
+        return 0;
 
     /*
      * FreeBSD has struct cmsgcred and struct sockcred.
@@ -727,46 +727,46 @@ anc_inspect_socket_creds(int level, int type, VALUE data, VALUE ret)
 
 #if defined(HAVE_TYPE_STRUCT_CMSGCRED) /* FreeBSD */
     if (RSTRING_LEN(data) == sizeof(struct cmsgcred)) {
-	struct cmsgcred cred;
+        struct cmsgcred cred;
         memcpy(&cred, RSTRING_PTR(data), sizeof(struct cmsgcred));
         rb_str_catf(ret, " pid=%u", cred.cmcred_pid);
         rb_str_catf(ret, " uid=%u", cred.cmcred_uid);
         rb_str_catf(ret, " euid=%u", cred.cmcred_euid);
         rb_str_catf(ret, " gid=%u", cred.cmcred_gid);
-	if (cred.cmcred_ngroups) {
-	    int i;
-	    const char *sep = " groups=";
-	    for (i = 0; i < cred.cmcred_ngroups; i++) {
-		rb_str_catf(ret, "%s%u", sep, cred.cmcred_groups[i]);
-		sep = ",";
-	    }
-	}
-	rb_str_cat2(ret, " (cmsgcred)");
+        if (cred.cmcred_ngroups) {
+            int i;
+            const char *sep = " groups=";
+            for (i = 0; i < cred.cmcred_ngroups; i++) {
+                rb_str_catf(ret, "%s%u", sep, cred.cmcred_groups[i]);
+                sep = ",";
+            }
+        }
+        rb_str_cat2(ret, " (cmsgcred)");
         return 1;
     }
 #endif
 #if defined(HAVE_TYPE_STRUCT_SOCKCRED) /* FreeBSD, NetBSD */
     if ((size_t)RSTRING_LEN(data) >= SOCKCREDSIZE(0)) {
-	struct sockcred cred0, *cred;
+        struct sockcred cred0, *cred;
         memcpy(&cred0, RSTRING_PTR(data), SOCKCREDSIZE(0));
-	if ((size_t)RSTRING_LEN(data) == SOCKCREDSIZE(cred0.sc_ngroups)) {
-	    cred = (struct sockcred *)ALLOCA_N(char, SOCKCREDSIZE(cred0.sc_ngroups));
-	    memcpy(cred, RSTRING_PTR(data), SOCKCREDSIZE(cred0.sc_ngroups));
-	    rb_str_catf(ret, " uid=%u", cred->sc_uid);
-	    rb_str_catf(ret, " euid=%u", cred->sc_euid);
-	    rb_str_catf(ret, " gid=%u", cred->sc_gid);
-	    rb_str_catf(ret, " egid=%u", cred->sc_egid);
-	    if (cred0.sc_ngroups) {
-		int i;
-		const char *sep = " groups=";
-		for (i = 0; i < cred0.sc_ngroups; i++) {
-		    rb_str_catf(ret, "%s%u", sep, cred->sc_groups[i]);
-		    sep = ",";
-		}
-	    }
-	    rb_str_cat2(ret, " (sockcred)");
-	    return 1;
-	}
+        if ((size_t)RSTRING_LEN(data) == SOCKCREDSIZE(cred0.sc_ngroups)) {
+            cred = (struct sockcred *)ALLOCA_N(char, SOCKCREDSIZE(cred0.sc_ngroups));
+            memcpy(cred, RSTRING_PTR(data), SOCKCREDSIZE(cred0.sc_ngroups));
+            rb_str_catf(ret, " uid=%u", cred->sc_uid);
+            rb_str_catf(ret, " euid=%u", cred->sc_euid);
+            rb_str_catf(ret, " gid=%u", cred->sc_gid);
+            rb_str_catf(ret, " egid=%u", cred->sc_egid);
+            if (cred0.sc_ngroups) {
+                int i;
+                const char *sep = " groups=";
+                for (i = 0; i < cred0.sc_ngroups; i++) {
+                    rb_str_catf(ret, "%s%u", sep, cred->sc_groups[i]);
+                    sep = ",";
+                }
+            }
+            rb_str_cat2(ret, " (sockcred)");
+            return 1;
+        }
     }
 #endif
     return 0;
@@ -906,37 +906,37 @@ inspect_bintime_as_abstime(int level, int optname, VALUE data, VALUE ret)
     if (RSTRING_LEN(data) == sizeof(struct bintime)) {
         struct bintime bt;
         struct tm tm;
-	uint64_t frac_h, frac_l;
-	uint64_t scale_h, scale_l;
-	uint64_t tmp1, tmp2;
-	uint64_t res_h, res_l;
+        uint64_t frac_h, frac_l;
+        uint64_t scale_h, scale_l;
+        uint64_t tmp1, tmp2;
+        uint64_t res_h, res_l;
         char buf[32];
         memcpy((char*)&bt, RSTRING_PTR(data), sizeof(bt));
         LOCALTIME(bt.sec, tm);
         strftime(buf, sizeof(buf), "%Y-%m-%d %H:%M:%S", &tm);
 
-	/* res_h = frac * 10**19 / 2**64 */
+        /* res_h = frac * 10**19 / 2**64 */
 
-	frac_h = bt.frac >> 32;
-	frac_l = bt.frac & 0xffffffff;
+        frac_h = bt.frac >> 32;
+        frac_l = bt.frac & 0xffffffff;
 
-	scale_h = 0x8ac72304; /* 0x8ac7230489e80000 == 10**19 */
-	scale_l = 0x89e80000;
+        scale_h = 0x8ac72304; /* 0x8ac7230489e80000 == 10**19 */
+        scale_l = 0x89e80000;
 
-	res_h = frac_h * scale_h;
-	res_l = frac_l * scale_l;
+        res_h = frac_h * scale_h;
+        res_l = frac_l * scale_l;
 
-	tmp1 = frac_h * scale_l;
-	res_h += tmp1 >> 32;
-	tmp2 = res_l;
-	res_l += tmp1 & 0xffffffff;
-	if (res_l < tmp2) res_h++;
+        tmp1 = frac_h * scale_l;
+        res_h += tmp1 >> 32;
+        tmp2 = res_l;
+        res_l += tmp1 & 0xffffffff;
+        if (res_l < tmp2) res_h++;
 
-	tmp1 = frac_l * scale_h;
-	res_h += tmp1 >> 32;
-	tmp2 = res_l;
-	res_l += tmp1 & 0xffffffff;
-	if (res_l < tmp2) res_h++;
+        tmp1 = frac_l * scale_h;
+        res_h += tmp1 >> 32;
+        tmp2 = res_l;
+        res_l += tmp1 & 0xffffffff;
+        if (res_l < tmp2) res_h++;
 
         rb_str_catf(ret, " %s.%019"PRIu64, buf, res_h);
         return 1;
@@ -1136,8 +1136,8 @@ rb_sendmsg(int fd, const struct msghdr *msg, int flags)
 
 static VALUE
 bsock_sendmsg_internal(VALUE sock, VALUE data, VALUE vflags,
-		       VALUE dest_sockaddr, VALUE controls, VALUE ex,
-		       int nonblock)
+                       VALUE dest_sockaddr, VALUE controls, VALUE ex,
+                       int nonblock)
 {
     rb_io_t *fptr;
     struct msghdr mh;
@@ -1160,15 +1160,15 @@ bsock_sendmsg_internal(VALUE sock, VALUE data, VALUE vflags,
     tmp = rb_str_tmp_frozen_acquire(data);
 
     if (!RB_TYPE_P(controls, T_ARRAY)) {
-	controls = rb_ary_new();
+        controls = rb_ary_new();
     }
     controls_num = RARRAY_LENINT(controls);
 
     if (controls_num) {
 #if defined(HAVE_STRUCT_MSGHDR_MSG_CONTROL)
-	int i;
-	size_t last_pad = 0;
-	const VALUE *controls_ptr = RARRAY_CONST_PTR(controls);
+        int i;
+        size_t last_pad = 0;
+        const VALUE *controls_ptr = RARRAY_CONST_PTR(controls);
 #if defined(__NetBSD__)
         int last_level = 0;
         int last_type = 0;
@@ -1215,9 +1215,9 @@ bsock_sendmsg_internal(VALUE sock, VALUE data, VALUE vflags,
             last_level = cmh.cmsg_level;
             last_type = cmh.cmsg_type;
 #endif
-	    last_pad = cspace - cmh.cmsg_len;
+            last_pad = cspace - cmh.cmsg_len;
         }
-	if (last_pad) {
+        if (last_pad) {
             /*
              * This code removes the last padding from msg_controllen.
              *
@@ -1242,10 +1242,10 @@ bsock_sendmsg_internal(VALUE sock, VALUE data, VALUE vflags,
             if (last_level == SOL_SOCKET && last_type == SCM_RIGHTS)
                 rb_str_set_len(controls_str, RSTRING_LEN(controls_str)-last_pad);
 #endif
-	}
-	RB_GC_GUARD(controls);
+        }
+        RB_GC_GUARD(controls);
 #else
-	rb_raise(rb_eNotImpError, "control message for sendmsg is unimplemented");
+        rb_raise(rb_eNotImpError, "control message for sendmsg is unimplemented");
 #endif
     }
 
@@ -1256,7 +1256,7 @@ bsock_sendmsg_internal(VALUE sock, VALUE data, VALUE vflags,
 #endif
 
     if (!NIL_P(dest_sockaddr))
-	SockAddrStringValue(dest_sockaddr);
+        SockAddrStringValue(dest_sockaddr);
 
     rb_io_check_closed(fptr);
 
@@ -1284,20 +1284,20 @@ bsock_sendmsg_internal(VALUE sock, VALUE data, VALUE vflags,
     ss = rb_sendmsg(fptr->fd, &mh, flags);
 
     if (ss == -1) {
-	int e;
-        if (!nonblock && rb_io_maybe_wait_writable(errno, fptr->self, Qnil)) {
+        int e;
+        if (!nonblock && rb_io_maybe_wait_writable(errno, fptr->self, RUBY_IO_TIMEOUT_DEFAULT)) {
             rb_io_check_closed(fptr);
             goto retry;
         }
-	e = errno;
-	if (nonblock && (e == EWOULDBLOCK || e == EAGAIN)) {
-	    if (ex == Qfalse) {
-		return sym_wait_writable;
-	    }
-	    rb_readwrite_syserr_fail(RB_IO_WAIT_WRITABLE, e,
-				     "sendmsg(2) would block");
-	}
-	rb_syserr_fail(e, "sendmsg(2)");
+        e = errno;
+        if (nonblock && (e == EWOULDBLOCK || e == EAGAIN)) {
+            if (ex == Qfalse) {
+                return sym_wait_writable;
+            }
+            rb_readwrite_syserr_fail(RB_IO_WAIT_WRITABLE, e,
+                                     "sendmsg(2) would block");
+        }
+        rb_syserr_fail(e, "sendmsg(2)");
     }
 #if defined(HAVE_STRUCT_MSGHDR_MSG_CONTROL)
     RB_GC_GUARD(controls_str);
@@ -1311,20 +1311,20 @@ bsock_sendmsg_internal(VALUE sock, VALUE data, VALUE vflags,
 #if defined(HAVE_SENDMSG)
 VALUE
 rsock_bsock_sendmsg(VALUE sock, VALUE data, VALUE flags, VALUE dest_sockaddr,
-		    VALUE controls)
+                    VALUE controls)
 {
     return bsock_sendmsg_internal(sock, data, flags, dest_sockaddr, controls,
-				  Qtrue, 0);
+                                  Qtrue, 0);
 }
 #endif
 
 #if defined(HAVE_SENDMSG)
 VALUE
 rsock_bsock_sendmsg_nonblock(VALUE sock, VALUE data, VALUE flags,
-			     VALUE dest_sockaddr, VALUE controls, VALUE ex)
+                             VALUE dest_sockaddr, VALUE controls, VALUE ex)
 {
     return bsock_sendmsg_internal(sock, data, flags, dest_sockaddr,
-				  controls, ex, 1);
+                                  controls, ex, 1);
 }
 #endif
 
@@ -1422,12 +1422,12 @@ make_io_for_unix_rights(VALUE ctl, struct cmsghdr *cmh, char *msg_end)
 {
     if (cmh->cmsg_level == SOL_SOCKET && cmh->cmsg_type == SCM_RIGHTS) {
         int *fdp, *end;
-	VALUE ary = rb_ary_new();
-	rb_ivar_set(ctl, rb_intern("unix_rights"), ary);
+        VALUE ary = rb_ary_new();
+        rb_ivar_set(ctl, rb_intern("unix_rights"), ary);
         fdp = (int *)CMSG_DATA(cmh);
         end = (int *)((char *)cmh + cmh->cmsg_len);
         while ((char *)fdp + sizeof(int) <= (char *)end &&
-	       (char *)fdp + sizeof(int) <= msg_end) {
+               (char *)fdp + sizeof(int) <= msg_end) {
             int fd = *fdp;
             struct stat stbuf;
             VALUE io;
@@ -1443,15 +1443,15 @@ make_io_for_unix_rights(VALUE ctl, struct cmsghdr *cmh, char *msg_end)
             rb_ary_push(ary, io);
             fdp++;
         }
-	OBJ_FREEZE(ary);
+        OBJ_FREEZE(ary);
     }
 }
 #endif
 
 static VALUE
 bsock_recvmsg_internal(VALUE sock,
-		VALUE vmaxdatlen, VALUE vflags, VALUE vmaxctllen,
-		VALUE scm_rights, VALUE ex, int nonblock)
+                VALUE vmaxdatlen, VALUE vflags, VALUE vmaxctllen,
+                VALUE scm_rights, VALUE ex, int nonblock)
 {
     rb_io_t *fptr;
     int grow_buffer;
@@ -1505,28 +1505,28 @@ bsock_recvmsg_internal(VALUE sock,
 
 #if !defined(HAVE_STRUCT_MSGHDR_MSG_CONTROL)
     if (grow_buffer) {
-	int socktype;
-	socklen_t optlen = (socklen_t)sizeof(socktype);
+        int socktype;
+        socklen_t optlen = (socklen_t)sizeof(socktype);
         if (getsockopt(fptr->fd, SOL_SOCKET, SO_TYPE, (void*)&socktype, &optlen) == -1) {
-	    rb_sys_fail("getsockopt(SO_TYPE)");
-	}
-	if (socktype == SOCK_STREAM)
-	    grow_buffer = 0;
+            rb_sys_fail("getsockopt(SO_TYPE)");
+        }
+        if (socktype == SOCK_STREAM)
+            grow_buffer = 0;
     }
 #endif
 
   retry:
     if (NIL_P(dat_str))
-	dat_str = rb_str_tmp_new(maxdatlen);
+        dat_str = rb_str_tmp_new(maxdatlen);
     else
-	rb_str_resize(dat_str, maxdatlen);
+        rb_str_resize(dat_str, maxdatlen);
     datbuf = RSTRING_PTR(dat_str);
 
 #if defined(HAVE_STRUCT_MSGHDR_MSG_CONTROL)
     if (NIL_P(ctl_str))
-	ctl_str = rb_str_tmp_new(maxctllen);
+        ctl_str = rb_str_tmp_new(maxctllen);
     else
-	rb_str_resize(ctl_str, maxctllen);
+        rb_str_resize(ctl_str, maxctllen);
     ctlbuf = RSTRING_PTR(ctl_str);
 #endif
 
@@ -1556,20 +1556,20 @@ bsock_recvmsg_internal(VALUE sock,
     ss = rb_recvmsg(fptr->fd, &mh, flags);
 
     if (ss == -1) {
-	int e;
-        if (!nonblock && rb_io_maybe_wait_readable(errno, fptr->self, Qnil)) {
+        int e;
+        if (!nonblock && rb_io_maybe_wait_readable(errno, fptr->self, RUBY_IO_TIMEOUT_DEFAULT)) {
             rb_io_check_closed(fptr);
             goto retry;
         }
-	e = errno;
-	if (nonblock && (e == EWOULDBLOCK || e == EAGAIN)) {
+        e = errno;
+        if (nonblock && (e == EWOULDBLOCK || e == EAGAIN)) {
             if (ex == Qfalse) {
                 return sym_wait_readable;
             }
-	    rb_readwrite_syserr_fail(RB_IO_WAIT_READABLE, e, "recvmsg(2) would block");
+            rb_readwrite_syserr_fail(RB_IO_WAIT_READABLE, e, "recvmsg(2) would block");
         }
 #if defined(HAVE_STRUCT_MSGHDR_MSG_CONTROL)
-	if (!gc_done && (e == EMFILE || e == EMSGSIZE)) {
+        if (!gc_done && (e == EMFILE || e == EMSGSIZE)) {
           /*
            * When SCM_RIGHTS hit the file descriptors limit:
            * - Linux 2.6.18 causes success with MSG_CTRUNC
@@ -1579,24 +1579,24 @@ bsock_recvmsg_internal(VALUE sock,
           gc_and_retry:
             rb_gc();
             gc_done = 1;
-	    goto retry;
+            goto retry;
         }
 #else
-	if (NIL_P(vmaxdatlen) && grow_buffer && e == EMSGSIZE)
-	    ss = (ssize_t)iov.iov_len;
-	else
+        if (NIL_P(vmaxdatlen) && grow_buffer && e == EMSGSIZE)
+            ss = (ssize_t)iov.iov_len;
+        else
 #endif
-	rb_syserr_fail(e, "recvmsg(2)");
+        rb_syserr_fail(e, "recvmsg(2)");
     }
 
     if (grow_buffer) {
-	int grown = 0;
-	if (NIL_P(vmaxdatlen) && ss != -1 && ss == (ssize_t)iov.iov_len) {
+        int grown = 0;
+        if (NIL_P(vmaxdatlen) && ss != -1 && ss == (ssize_t)iov.iov_len) {
             if (SIZE_MAX/2 < maxdatlen)
                 rb_raise(rb_eArgError, "max data length too big");
-	    maxdatlen *= 2;
-	    grown = 1;
-	}
+            maxdatlen *= 2;
+            grown = 1;
+        }
 #if defined(HAVE_STRUCT_MSGHDR_MSG_CONTROL)
         if (NIL_P(vmaxctllen) && (mh.msg_flags & MSG_CTRUNC)) {
 #define BIG_ENOUGH_SPACE 65536
@@ -1605,9 +1605,9 @@ bsock_recvmsg_internal(VALUE sock,
                 /* there are big space bug truncated.
                  * file descriptors limit? */
                 if (!gc_done) {
-		    rsock_discard_cmsg_resource(&mh, (flags & MSG_PEEK) != 0);
+                    rsock_discard_cmsg_resource(&mh, (flags & MSG_PEEK) != 0);
                     goto gc_and_retry;
-		}
+                }
             }
             else {
                 if (SIZE_MAX/2 < maxctllen)
@@ -1616,13 +1616,13 @@ bsock_recvmsg_internal(VALUE sock,
                 grown = 1;
             }
 #undef BIG_ENOUGH_SPACE
-	}
+        }
 #endif
-	if (grown) {
+        if (grown) {
             rsock_discard_cmsg_resource(&mh, (flags & MSG_PEEK) != 0);
-	    goto retry;
-	}
-	else {
+            goto retry;
+        }
+        else {
             grow_buffer = 0;
             if (flags != orig_flags) {
                 rsock_discard_cmsg_resource(&mh, (flags & MSG_PEEK) != 0);
@@ -1636,31 +1636,31 @@ bsock_recvmsg_internal(VALUE sock,
         dat_str = rb_str_new(datbuf, ss);
     else {
         rb_str_resize(dat_str, ss);
-	rb_obj_reveal(dat_str, rb_cString);
+        rb_obj_reveal(dat_str, rb_cString);
     }
 
     ret = rb_ary_new3(3, dat_str,
                          rsock_io_socket_addrinfo(sock, mh.msg_name, mh.msg_namelen),
 #if defined(HAVE_STRUCT_MSGHDR_MSG_CONTROL)
-			 INT2NUM(mh.msg_flags)
+                         INT2NUM(mh.msg_flags)
 #else
-			 Qnil
+                         Qnil
 #endif
-			 );
+                         );
 
 #if defined(HAVE_STRUCT_MSGHDR_MSG_CONTROL)
     family = rsock_getfamily(fptr);
     if (mh.msg_controllen) {
-	char *msg_end = (char *)mh.msg_control + mh.msg_controllen;
+        char *msg_end = (char *)mh.msg_control + mh.msg_controllen;
         for (cmh = CMSG_FIRSTHDR(&mh); cmh != NULL; cmh = CMSG_NXTHDR(&mh, cmh)) {
             VALUE ctl;
-	    char *ctl_end;
+            char *ctl_end;
             size_t clen;
             if (cmh->cmsg_len == 0) {
                 rb_raise(rb_eTypeError, "invalid control message (cmsg_len == 0)");
             }
             ctl_end = (char*)cmh + cmh->cmsg_len;
-	    clen = (ctl_end <= msg_end ? ctl_end : msg_end) - (char*)CMSG_DATA(cmh);
+            clen = (ctl_end <= msg_end ? ctl_end : msg_end) - (char*)CMSG_DATA(cmh);
             ctl = ancdata_new(family, cmh->cmsg_level, cmh->cmsg_type, rb_str_new((char*)CMSG_DATA(cmh), clen));
             if (request_scm_rights)
                 make_io_for_unix_rights(ctl, cmh, msg_end);
@@ -1679,7 +1679,7 @@ bsock_recvmsg_internal(VALUE sock,
 #if defined(HAVE_RECVMSG)
 VALUE
 rsock_bsock_recvmsg(VALUE sock, VALUE dlen, VALUE flags, VALUE clen,
-		    VALUE scm_rights)
+                    VALUE scm_rights)
 {
     VALUE ex = Qtrue;
     return bsock_recvmsg_internal(sock, dlen, flags, clen, scm_rights, ex, 0);
@@ -1689,7 +1689,7 @@ rsock_bsock_recvmsg(VALUE sock, VALUE dlen, VALUE flags, VALUE clen,
 #if defined(HAVE_RECVMSG)
 VALUE
 rsock_bsock_recvmsg_nonblock(VALUE sock, VALUE dlen, VALUE flags, VALUE clen,
-			     VALUE scm_rights, VALUE ex)
+                             VALUE scm_rights, VALUE ex)
 {
     return bsock_recvmsg_internal(sock, dlen, flags, clen, scm_rights, ex, 1);
 }
diff --git a/ext/socket/basicsocket.c b/ext/socket/basicsocket.c
index 44fb7a4eb7..54c369f6fc 100644
--- a/ext/socket/basicsocket.c
+++ b/ext/socket/basicsocket.c
@@ -94,16 +94,16 @@ bsock_shutdown(int argc, VALUE *argv, VALUE sock)
 
     rb_scan_args(argc, argv, "01", &howto);
     if (howto == Qnil)
-	how = SHUT_RDWR;
+        how = SHUT_RDWR;
     else {
-	how = rsock_shutdown_how_arg(howto);
+        how = rsock_shutdown_how_arg(howto);
         if (how != SHUT_WR && how != SHUT_RD && how != SHUT_RDWR) {
-	    rb_raise(rb_eArgError, "`how' should be either :SHUT_RD, :SHUT_WR, :SHUT_RDWR");
-	}
+            rb_raise(rb_eArgError, "`how' should be either :SHUT_RD, :SHUT_WR, :SHUT_RDWR");
+        }
     }
     GetOpenFile(sock, fptr);
     if (shutdown(fptr->fd, how) == -1)
-	rb_sys_fail("shutdown(2)");
+        rb_sys_fail("shutdown(2)");
 
     return INT2FIX(0);
 }
@@ -126,7 +126,7 @@ bsock_close_read(VALUE sock)
     GetOpenFile(sock, fptr);
     shutdown(fptr->fd, 0);
     if (!(fptr->mode & FMODE_WRITABLE)) {
-	return rb_io_close(sock);
+        return rb_io_close(sock);
     }
     fptr->mode &= ~FMODE_READABLE;
 
@@ -155,7 +155,7 @@ bsock_close_write(VALUE sock)
 
     GetOpenFile(sock, fptr);
     if (!(fptr->mode & FMODE_READABLE)) {
-	return rb_io_close(sock);
+        return rb_io_close(sock);
     }
     shutdown(fptr->fd, 1);
     fptr->mode &= ~FMODE_WRITABLE;
@@ -246,21 +246,21 @@ bsock_setsockopt(int argc, VALUE *argv, VALUE sock)
 
     switch (TYPE(val)) {
       case T_FIXNUM:
-	i = FIX2INT(val);
-	goto numval;
+        i = FIX2INT(val);
+        goto numval;
       case T_FALSE:
-	i = 0;
-	goto numval;
+        i = 0;
+        goto numval;
       case T_TRUE:
-	i = 1;
+        i = 1;
       numval:
-	v = (char*)&i; vlen = (int)sizeof(i);
-	break;
+        v = (char*)&i; vlen = (int)sizeof(i);
+        break;
       default:
-	StringValue(val);
-	v = RSTRING_PTR(val);
-	vlen = RSTRING_SOCKLEN(val);
-	break;
+        StringValue(val);
+        v = RSTRING_PTR(val);
+        vlen = RSTRING_SOCKLEN(val);
+        break;
     }
 
     rb_io_check_closed(fptr);
@@ -357,7 +357,7 @@ bsock_getsockopt(VALUE sock, VALUE lev, VALUE optname)
     rb_io_check_closed(fptr);
 
     if (getsockopt(fptr->fd, level, option, buf, &len) < 0)
-	rsock_sys_fail_path("getsockopt(2)", fptr->pathv);
+        rsock_sys_fail_path("getsockopt(2)", fptr->pathv);
 
     return rsock_sockopt_new(family, level, option, rb_str_new(buf, len));
 }
@@ -385,7 +385,7 @@ bsock_getsockname(VALUE sock)
 
     GetOpenFile(sock, fptr);
     if (getsockname(fptr->fd, &buf.addr, &len) < 0)
-	rb_sys_fail("getsockname(2)");
+        rb_sys_fail("getsockname(2)");
     if (len0 < len) len = len0;
     return rb_str_new((char*)&buf, len);
 }
@@ -416,7 +416,7 @@ bsock_getpeername(VALUE sock)
 
     GetOpenFile(sock, fptr);
     if (getpeername(fptr->fd, &buf.addr, &len) < 0)
-	rb_sys_fail("getpeername(2)");
+        rb_sys_fail("getpeername(2)");
     if (len0 < len) len = len0;
     return rb_str_new((char*)&buf, len);
 }
@@ -453,7 +453,7 @@ bsock_getpeereid(VALUE self)
     gid_t egid;
     GetOpenFile(self, fptr);
     if (getpeereid(fptr->fd, &euid, &egid) == -1)
-	rb_sys_fail("getpeereid(3)");
+        rb_sys_fail("getpeereid(3)");
     return rb_assoc_new(UIDT2NUM(euid), GIDT2NUM(egid));
 #elif defined(SO_PEERCRED) /* GNU/Linux */
     rb_io_t *fptr;
@@ -461,7 +461,7 @@ bsock_getpeereid(VALUE self)
     socklen_t len = sizeof(cred);
     GetOpenFile(self, fptr);
     if (getsockopt(fptr->fd, SOL_SOCKET, SO_PEERCRED, &cred, &len) == -1)
-	rb_sys_fail("getsockopt(SO_PEERCRED)");
+        rb_sys_fail("getsockopt(SO_PEERCRED)");
     return rb_assoc_new(UIDT2NUM(cred.uid), GIDT2NUM(cred.gid));
 #elif defined(HAVE_GETPEERUCRED) /* Solaris */
     rb_io_t *fptr;
@@ -469,7 +469,7 @@ bsock_getpeereid(VALUE self)
     VALUE ret;
     GetOpenFile(self, fptr);
     if (getpeerucred(fptr->fd, &uc) == -1)
-	rb_sys_fail("getpeerucred(3C)");
+        rb_sys_fail("getpeerucred(3C)");
     ret = rb_assoc_new(UIDT2NUM(ucred_geteuid(uc)), GIDT2NUM(ucred_getegid(uc)));
     ucred_free(uc);
     return ret;
@@ -506,7 +506,7 @@ bsock_local_address(VALUE sock)
 
     GetOpenFile(sock, fptr);
     if (getsockname(fptr->fd, &buf.addr, &len) < 0)
-	rb_sys_fail("getsockname(2)");
+        rb_sys_fail("getsockname(2)");
     if (len0 < len) len = len0;
     return rsock_fd_socket_addrinfo(fptr->fd, &buf.addr, len);
 }
@@ -540,7 +540,7 @@ bsock_remote_address(VALUE sock)
 
     GetOpenFile(sock, fptr);
     if (getpeername(fptr->fd, &buf.addr, &len) < 0)
-	rb_sys_fail("getpeername(2)");
+        rb_sys_fail("getpeername(2)");
     if (len0 < len) len = len0;
     return rsock_fd_socket_addrinfo(fptr->fd, &buf.addr, len);
 }
@@ -601,7 +601,7 @@ rsock_bsock_send(int argc, VALUE *argv, VALUE socket)
 
         if (n >= 0) return SSIZET2NUM(n);
 
-        if (rb_io_maybe_wait_writable(errno, socket, Qnil)) {
+        if (rb_io_maybe_wait_writable(errno, socket, RUBY_IO_TIMEOUT_DEFAULT)) {
             continue;
         }
 
@@ -656,10 +656,10 @@ bsock_do_not_reverse_lookup_set(VALUE sock, VALUE state)
 
     GetOpenFile(sock, fptr);
     if (RTEST(state)) {
-	fptr->mode |= FMODE_NOREVLOOKUP;
+        fptr->mode |= FMODE_NOREVLOOKUP;
     }
     else {
-	fptr->mode &= ~FMODE_NOREVLOOKUP;
+        fptr->mode &= ~FMODE_NOREVLOOKUP;
     }
     return sock;
 }
@@ -747,9 +747,9 @@ rsock_init_basicsocket(void)
     rb_undef_method(rb_cBasicSocket, "initialize");
 
     rb_define_singleton_method(rb_cBasicSocket, "do_not_reverse_lookup",
-			       bsock_do_not_rev_lookup, 0);
+                               bsock_do_not_rev_lookup, 0);
     rb_define_singleton_method(rb_cBasicSocket, "do_not_reverse_lookup=",
-			       bsock_do_not_rev_lookup_set, 1);
+                               bsock_do_not_rev_lookup_set, 1);
     rb_define_singleton_method(rb_cBasicSocket, "for_fd", bsock_s_for_fd, 1);
 
     rb_define_method(rb_cBasicSocket, "close_read", bsock_close_read, 0);
@@ -770,23 +770,23 @@ rsock_init_basicsocket(void)
 
     /* for ext/socket/lib/socket.rb use only: */
     rb_define_private_method(rb_cBasicSocket,
-			     "__recv_nonblock", bsock_recv_nonblock, 4);
+                             "__recv_nonblock", bsock_recv_nonblock, 4);
 
 #if MSG_DONTWAIT_RELIABLE
     rb_define_private_method(rb_cBasicSocket,
-			     "__read_nonblock", rsock_read_nonblock, 3);
+                             "__read_nonblock", rsock_read_nonblock, 3);
     rb_define_private_method(rb_cBasicSocket,
-			     "__write_nonblock", rsock_write_nonblock, 2);
+                             "__write_nonblock", rsock_write_nonblock, 2);
 #endif
 
     /* in ancdata.c */
     rb_define_private_method(rb_cBasicSocket, "__sendmsg",
-			     rsock_bsock_sendmsg, 4);
+                             rsock_bsock_sendmsg, 4);
     rb_define_private_method(rb_cBasicSocket, "__sendmsg_nonblock",
-			     rsock_bsock_sendmsg_nonblock, 5);
+                             rsock_bsock_sendmsg_nonblock, 5);
     rb_define_private_method(rb_cBasicSocket, "__recvmsg",
-			     rsock_bsock_recvmsg, 4);
+                             rsock_bsock_recvmsg, 4);
     rb_define_private_method(rb_cBasicSocket, "__recvmsg_nonblock",
-			    rsock_bsock_recvmsg_nonblock, 5);
+                            rsock_bsock_recvmsg_nonblock, 5);
 
 }
diff --git a/ext/socket/constants.c b/ext/socket/constants.c
index 1bbb53b173..1213f2ae17 100644
--- a/ext/socket/constants.c
+++ b/ext/socket/constants.c
@@ -26,14 +26,14 @@ constant_arg(VALUE arg, int (*str_to_int)(const char*, long, int*), const char *
         goto str;
     }
     else if (!NIL_P(tmp = rb_check_string_type(arg))) {
-	arg = tmp;
+        arg = tmp;
       str:
         ptr = RSTRING_PTR(arg);
         if (str_to_int(ptr, RSTRING_LEN(arg), &ret) == -1)
-	    rb_raise(rb_eSocket, "%s: %s", errmsg, ptr);
+            rb_raise(rb_eSocket, "%s: %s", errmsg, ptr);
     }
     else {
-	ret = NUM2INT(arg);
+        ret = NUM2INT(arg);
     }
     return ret;
 }
diff --git a/ext/socket/depend b/ext/socket/depend
index ffe2fce844..28c5540cd6 100644
--- a/ext/socket/depend
+++ b/ext/socket/depend
@@ -197,6 +197,7 @@ ancdata.o: $(top_srcdir)/internal/string.h
 ancdata.o: $(top_srcdir)/internal/thread.h
 ancdata.o: $(top_srcdir)/internal/vm.h
 ancdata.o: $(top_srcdir)/internal/warnings.h
+ancdata.o: $(top_srcdir)/shape.h
 ancdata.o: ancdata.c
 ancdata.o: constdefs.h
 ancdata.o: rubysocket.h
@@ -388,6 +389,7 @@ basicsocket.o: $(top_srcdir)/internal/string.h
 basicsocket.o: $(top_srcdir)/internal/thread.h
 basicsocket.o: $(top_srcdir)/internal/vm.h
 basicsocket.o: $(top_srcdir)/internal/warnings.h
+basicsocket.o: $(top_srcdir)/shape.h
 basicsocket.o: basicsocket.c
 basicsocket.o: constdefs.h
 basicsocket.o: rubysocket.h
@@ -579,6 +581,7 @@ constants.o: $(top_srcdir)/internal/string.h
 constants.o: $(top_srcdir)/internal/thread.h
 constants.o: $(top_srcdir)/internal/vm.h
 constants.o: $(top_srcdir)/internal/warnings.h
+constants.o: $(top_srcdir)/shape.h
 constants.o: constants.c
 constants.o: constdefs.c
 constants.o: constdefs.h
@@ -771,6 +774,7 @@ ifaddr.o: $(top_srcdir)/internal/string.h
 ifaddr.o: $(top_srcdir)/internal/thread.h
 ifaddr.o: $(top_srcdir)/internal/vm.h
 ifaddr.o: $(top_srcdir)/internal/warnings.h
+ifaddr.o: $(top_srcdir)/shape.h
 ifaddr.o: constdefs.h
 ifaddr.o: ifaddr.c
 ifaddr.o: rubysocket.h
@@ -962,6 +966,7 @@ init.o: $(top_srcdir)/internal/string.h
 init.o: $(top_srcdir)/internal/thread.h
 init.o: $(top_srcdir)/internal/vm.h
 init.o: $(top_srcdir)/internal/warnings.h
+init.o: $(top_srcdir)/shape.h
 init.o: constdefs.h
 init.o: init.c
 init.o: rubysocket.h
@@ -1153,6 +1158,7 @@ ipsocket.o: $(top_srcdir)/internal/string.h
 ipsocket.o: $(top_srcdir)/internal/thread.h
 ipsocket.o: $(top_srcdir)/internal/vm.h
 ipsocket.o: $(top_srcdir)/internal/warnings.h
+ipsocket.o: $(top_srcdir)/shape.h
 ipsocket.o: constdefs.h
 ipsocket.o: ipsocket.c
 ipsocket.o: rubysocket.h
@@ -1344,6 +1350,7 @@ option.o: $(top_srcdir)/internal/string.h
 option.o: $(top_srcdir)/internal/thread.h
 option.o: $(top_srcdir)/internal/vm.h
 option.o: $(top_srcdir)/internal/warnings.h
+option.o: $(top_srcdir)/shape.h
 option.o: constdefs.h
 option.o: option.c
 option.o: rubysocket.h
@@ -1535,6 +1542,7 @@ raddrinfo.o: $(top_srcdir)/internal/string.h
 raddrinfo.o: $(top_srcdir)/internal/thread.h
 raddrinfo.o: $(top_srcdir)/internal/vm.h
 raddrinfo.o: $(top_srcdir)/internal/warnings.h
+raddrinfo.o: $(top_srcdir)/shape.h
 raddrinfo.o: constdefs.h
 raddrinfo.o: raddrinfo.c
 raddrinfo.o: rubysocket.h
@@ -1726,6 +1734,7 @@ socket.o: $(top_srcdir)/internal/string.h
 socket.o: $(top_srcdir)/internal/thread.h
 socket.o: $(top_srcdir)/internal/vm.h
 socket.o: $(top_srcdir)/internal/warnings.h
+socket.o: $(top_srcdir)/shape.h
 socket.o: constdefs.h
 socket.o: rubysocket.h
 socket.o: socket.c
@@ -1917,6 +1926,7 @@ sockssocket.o: $(top_srcdir)/internal/string.h
 sockssocket.o: $(top_srcdir)/internal/thread.h
 sockssocket.o: $(top_srcdir)/internal/vm.h
 sockssocket.o: $(top_srcdir)/internal/warnings.h
+sockssocket.o: $(top_srcdir)/shape.h
 sockssocket.o: constdefs.h
 sockssocket.o: rubysocket.h
 sockssocket.o: sockport.h
@@ -2108,6 +2118,7 @@ tcpserver.o: $(top_srcdir)/internal/string.h
 tcpserver.o: $(top_srcdir)/internal/thread.h
 tcpserver.o: $(top_srcdir)/internal/vm.h
 tcpserver.o: $(top_srcdir)/internal/warnings.h
+tcpserver.o: $(top_srcdir)/shape.h
 tcpserver.o: constdefs.h
 tcpserver.o: rubysocket.h
 tcpserver.o: sockport.h
@@ -2299,6 +2310,7 @@ tcpsocket.o: $(top_srcdir)/internal/string.h
 tcpsocket.o: $(top_srcdir)/internal/thread.h
 tcpsocket.o: $(top_srcdir)/internal/vm.h
 tcpsocket.o: $(top_srcdir)/internal/warnings.h
+tcpsocket.o: $(top_srcdir)/shape.h
 tcpsocket.o: constdefs.h
 tcpsocket.o: rubysocket.h
 tcpsocket.o: sockport.h
@@ -2490,6 +2502,7 @@ udpsocket.o: $(top_srcdir)/internal/string.h
 udpsocket.o: $(top_srcdir)/internal/thread.h
 udpsocket.o: $(top_srcdir)/internal/vm.h
 udpsocket.o: $(top_srcdir)/internal/warnings.h
+udpsocket.o: $(top_srcdir)/shape.h
 udpsocket.o: constdefs.h
 udpsocket.o: rubysocket.h
 udpsocket.o: sockport.h
@@ -2681,6 +2694,7 @@ unixserver.o: $(top_srcdir)/internal/string.h
 unixserver.o: $(top_srcdir)/internal/thread.h
 unixserver.o: $(top_srcdir)/internal/vm.h
 unixserver.o: $(top_srcdir)/internal/warnings.h
+unixserver.o: $(top_srcdir)/shape.h
 unixserver.o: constdefs.h
 unixserver.o: rubysocket.h
 unixserver.o: sockport.h
@@ -2872,6 +2886,7 @@ unixsocket.o: $(top_srcdir)/internal/string.h
 unixsocket.o: $(top_srcdir)/internal/thread.h
 unixsocket.o: $(top_srcdir)/internal/vm.h
 unixsocket.o: $(top_srcdir)/internal/warnings.h
+unixsocket.o: $(top_srcdir)/shape.h
 unixsocket.o: constdefs.h
 unixsocket.o: rubysocket.h
 unixsocket.o: sockport.h
diff --git a/ext/socket/extconf.rb b/ext/socket/extconf.rb
index b70a862414..37ff216560 100644
--- a/ext/socket/extconf.rb
+++ b/ext/socket/extconf.rb
@@ -316,6 +316,7 @@ end
   netpacket/packet.h
   net/ethernet.h
   sys/un.h
+  afunix.h
   ifaddrs.h
   sys/ioctl.h
   sys/sockio.h
@@ -551,7 +552,7 @@ EOS
   end
 
   if !have_macro("IPPROTO_IPV6", headers) && have_const("IPPROTO_IPV6", headers)
-    IO.read(File.join(File.dirname(__FILE__), "mkconstants.rb")).sub(/\A.*^__END__$/m, '').split(/\r?\n/).grep(/\AIPPROTO_\w*/){$&}.each {|name|
+    File.read(File.join(File.dirname(__FILE__), "mkconstants.rb")).sub(/\A.*^__END__$/m, '').split(/\r?\n/).grep(/\AIPPROTO_\w*/){$&}.each {|name|
       have_const(name, headers) unless $defs.include?("-DHAVE_CONST_#{name.upcase}")
     }
   end
@@ -655,12 +656,20 @@ EOS
   end
 
   hdr = "netinet6/in6.h"
-  if /darwin/ =~ RUBY_PLATFORM and !try_compile(<<"SRC", nil, :werror=>true)
+  /darwin/ =~ RUBY_PLATFORM and
+  checking_for("if apple's #{hdr} needs s6_addr patch") {!try_compile(<<"SRC", nil, :werror=>true)} and
 #include <netinet/in.h>
 int t(struct in6_addr *addr) {return IN6_IS_ADDR_UNSPECIFIED(addr);}
 SRC
-    print "fixing apple's netinet6/in6.h ..."; $stdout.flush
-    in6 = File.read("/usr/include/#{hdr}")
+  checking_for("fixing apple's #{hdr}", "%s") do
+    file = xpopen(%w"clang -include netinet/in.h -E -xc -", in: IO::NULL) do |f|
+      re = %r[^# *\d+ *"(.*/netinet/in\.h)"]
+      Logging.message "  grep(#{re})\n"
+      f.read[re, 1]
+    end
+    Logging.message "Substitute from #{file}\n"
+
+    in6 = File.read(file)
     if in6.gsub!(/\*\(const\s+__uint32_t\s+\*\)\(const\s+void\s+\*\)\(&(\(\w+\))->s6_addr\[(\d+)\]\)/) do
         i, r = $2.to_i.divmod(4)
         if r.zero?
@@ -670,12 +679,12 @@ SRC
         end
       end
       FileUtils.mkdir_p(File.dirname(hdr))
-      open(hdr, "w") {|f| f.write(in6)}
+      File.write(hdr, in6)
       $distcleanfiles << hdr
       $distcleandirs << File.dirname(hdr)
-      puts "done"
+      "done"
     else
-      puts "not needed"
+      "not needed"
     end
   end
   create_makefile("socket")
diff --git a/ext/socket/getaddrinfo.c b/ext/socket/getaddrinfo.c
index ce6dc40478..95a2feb3be 100644
--- a/ext/socket/getaddrinfo.c
+++ b/ext/socket/getaddrinfo.c
@@ -98,42 +98,42 @@ static struct in6_addr faith_prefix = IN6ADDR_ANY_INIT;
 
 static const char in_addrany[] = { 0, 0, 0, 0 };
 static const char in6_addrany[] = {
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
 };
 static const char in_loopback[] = { 127, 0, 0, 1 };
 static const char in6_loopback[] = {
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
+        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
 };
 
 struct sockinet {
-	u_char	si_len;
-	u_char	si_family;
-	u_short	si_port;
+        u_char	si_len;
+        u_char	si_family;
+        u_short	si_port;
 };
 
 static const struct afd {
-	int a_af;
-	int a_addrlen;
-	int a_socklen;
-	int a_off;
-	const char *a_addrany;
-	const char *a_loopback;
+        int a_af;
+        int a_addrlen;
+        int a_socklen;
+        int a_off;
+        const char *a_addrany;
+        const char *a_loopback;
 } afdl [] = {
 #ifdef INET6
 #define N_INET6 0
-	{PF_INET6, sizeof(struct in6_addr),
-	 sizeof(struct sockaddr_in6),
-	 offsetof(struct sockaddr_in6, sin6_addr),
-	 in6_addrany, in6_loopback},
+        {PF_INET6, sizeof(struct in6_addr),
+         sizeof(struct sockaddr_in6),
+         offsetof(struct sockaddr_in6, sin6_addr),
+         in6_addrany, in6_loopback},
 #define N_INET  1
 #else
 #define N_INET  0
 #endif
-	{PF_INET, sizeof(struct in_addr),
-	 sizeof(struct sockaddr_in),
-	 offsetof(struct sockaddr_in, sin_addr),
-	 in_addrany, in_loopback},
-	{0, 0, 0, 0, NULL, NULL},
+        {PF_INET, sizeof(struct in_addr),
+         sizeof(struct sockaddr_in),
+         offsetof(struct sockaddr_in, sin_addr),
+         in_addrany, in_loopback},
+        {0, 0, 0, 0, NULL, NULL},
 };
 
 #ifdef INET6
@@ -143,58 +143,58 @@ static const struct afd {
 #endif
 
 static int get_name __P((const char *, const struct afd *,
-			  struct addrinfo **, char *, struct addrinfo *,
-			  int));
+                          struct addrinfo **, char *, struct addrinfo *,
+                          int));
 static int get_addr __P((const char *, int, struct addrinfo **,
-			struct addrinfo *, int));
+                        struct addrinfo *, int));
 static int str_isnumber __P((const char *));
 
 #ifndef HAVE_GAI_STRERROR
 static const char *const ai_errlist[] = {
-	"success.",
-	"address family for hostname not supported.",	/* EAI_ADDRFAMILY */
-	"temporary failure in name resolution.",	/* EAI_AGAIN      */
-	"invalid value for ai_flags.",		       	/* EAI_BADFLAGS   */
-	"non-recoverable failure in name resolution.", 	/* EAI_FAIL       */
-	"ai_family not supported.",			/* EAI_FAMILY     */
-	"memory allocation failure.", 			/* EAI_MEMORY     */
-	"no address associated with hostname.", 	/* EAI_NODATA     */
-	"hostname nor servname provided, or not known.",/* EAI_NONAME     */
-	"servname not supported for ai_socktype.",	/* EAI_SERVICE    */
-	"ai_socktype not supported.", 			/* EAI_SOCKTYPE   */
-	"system error returned in errno.", 		/* EAI_SYSTEM     */
-	"invalid value for hints.",			/* EAI_BADHINTS	  */
-	"resolved protocol is unknown.",		/* EAI_PROTOCOL   */
-	"unknown error.", 				/* EAI_MAX        */
+        "success.",
+        "address family for hostname not supported.",	/* EAI_ADDRFAMILY */
+        "temporary failure in name resolution.",	/* EAI_AGAIN      */
+        "invalid value for ai_flags.",		       	/* EAI_BADFLAGS   */
+        "non-recoverable failure in name resolution.", 	/* EAI_FAIL       */
+        "ai_family not supported.",			/* EAI_FAMILY     */
+        "memory allocation failure.", 			/* EAI_MEMORY     */
+        "no address associated with hostname.", 	/* EAI_NODATA     */
+        "hostname nor servname provided, or not known.",/* EAI_NONAME     */
+        "servname not supported for ai_socktype.",	/* EAI_SERVICE    */
+        "ai_socktype not supported.", 			/* EAI_SOCKTYPE   */
+        "system error returned in errno.", 		/* EAI_SYSTEM     */
+        "invalid value for hints.",			/* EAI_BADHINTS	  */
+        "resolved protocol is unknown.",		/* EAI_PROTOCOL   */
+        "unknown error.", 				/* EAI_MAX        */
 };
 #endif
 
 #define GET_CANONNAME(ai, str) \
 if (pai->ai_flags & AI_CANONNAME) {\
-	if (((ai)->ai_canonname = (char *)malloc(strlen(str) + 1)) != NULL) {\
-		strcpy((ai)->ai_canonname, (str));\
-	} else {\
-		error = EAI_MEMORY;\
-		goto free;\
-	}\
+        if (((ai)->ai_canonname = (char *)malloc(strlen(str) + 1)) != NULL) {\
+                strcpy((ai)->ai_canonname, (str));\
+        } else {\
+                error = EAI_MEMORY;\
+                goto free;\
+        }\
 }
 
 #define GET_AI(ai, afd, addr, port) {\
-	char *p;\
-	if (((ai) = (struct addrinfo *)malloc(sizeof(struct addrinfo) +\
-					      ((afd)->a_socklen)))\
-	    == NULL) {\
-		error = EAI_MEMORY;\
-		goto free;\
-	}\
-	memcpy((ai), pai, sizeof(struct addrinfo));\
-	(ai)->ai_addr = (struct sockaddr *)((ai) + 1);\
-	(ai)->ai_family = (afd)->a_af;\
-	(ai)->ai_addrlen = (afd)->a_socklen;\
-	INIT_SOCKADDR((ai)->ai_addr, (afd)->a_af, (afd)->a_socklen);\
-	((struct sockinet *)(ai)->ai_addr)->si_port = (port);\
-	p = (char *)((ai)->ai_addr);\
-	memcpy(p + (afd)->a_off, (addr), (afd)->a_addrlen);\
+        char *p;\
+        if (((ai) = (struct addrinfo *)malloc(sizeof(struct addrinfo) +\
+                                              ((afd)->a_socklen)))\
+            == NULL) {\
+                error = EAI_MEMORY;\
+                goto free;\
+        }\
+        memcpy((ai), pai, sizeof(struct addrinfo));\
+        (ai)->ai_addr = (struct sockaddr *)((ai) + 1);\
+        (ai)->ai_family = (afd)->a_af;\
+        (ai)->ai_addrlen = (afd)->a_socklen;\
+        INIT_SOCKADDR((ai)->ai_addr, (afd)->a_af, (afd)->a_socklen);\
+        ((struct sockinet *)(ai)->ai_addr)->si_port = (port);\
+        p = (char *)((ai)->ai_addr);\
+        memcpy(p + (afd)->a_off, (addr), (afd)->a_addrlen);\
 }
 
 #define ERR(err) { error = (err); goto bad; }
@@ -206,36 +206,36 @@ const
 char *
 gai_strerror(int ecode)
 {
-	if (ecode < 0 || ecode > EAI_MAX)
-		ecode = EAI_MAX;
-	return (char *)ai_errlist[ecode];
+        if (ecode < 0 || ecode > EAI_MAX)
+                ecode = EAI_MAX;
+        return (char *)ai_errlist[ecode];
 }
 #endif
 
 void
 freeaddrinfo(struct addrinfo *ai)
 {
-	struct addrinfo *next;
-
-	do {
-		next = ai->ai_next;
-		if (ai->ai_canonname)
-			free(ai->ai_canonname);
-		/* no need to free(ai->ai_addr) */
-		free(ai);
-	} while ((ai = next) != NULL);
+        struct addrinfo *next;
+
+        do {
+                next = ai->ai_next;
+                if (ai->ai_canonname)
+                        free(ai->ai_canonname);
+                /* no need to free(ai->ai_addr) */
+                free(ai);
+        } while ((ai = next) != NULL);
 }
 
 static int
 str_isnumber(const char *p)
 {
-	char *q = (char *)p;
-	while (*q) {
-		if (! isdigit(*q))
-			return NO;
-		q++;
-	}
-	return YES;
+        char *q = (char *)p;
+        while (*q) {
+                if (! isdigit(*q))
+                        return NO;
+                q++;
+        }
+        return YES;
 }
 
 #ifndef HAVE_INET_PTON
@@ -243,435 +243,435 @@ str_isnumber(const char *p)
 static int
 inet_pton(int af, const char *hostname, void *pton)
 {
-	struct in_addr in;
+        struct in_addr in;
 
 #ifdef HAVE_INET_ATON
-	if (!inet_aton(hostname, &in))
-	    return 0;
+        if (!inet_aton(hostname, &in))
+            return 0;
 #else
-	int d1, d2, d3, d4;
-	char ch;
-
-	if (sscanf(hostname, "%d.%d.%d.%d%c", &d1, &d2, &d3, &d4, &ch) == 4 &&
-	    0 <= d1 && d1 <= 255 && 0 <= d2 && d2 <= 255 &&
-	    0 <= d3 && d3 <= 255 && 0 <= d4 && d4 <= 255) {
-	    in.s_addr = htonl(
-		((long) d1 << 24) | ((long) d2 << 16) |
-		((long) d3 << 8) | ((long) d4 << 0));
-	}
-	else {
-	    return 0;
-	}
-#endif
-	memcpy(pton, &in, sizeof(in));
-	return 1;
+        int d1, d2, d3, d4;
+        char ch;
+
+        if (sscanf(hostname, "%d.%d.%d.%d%c", &d1, &d2, &d3, &d4, &ch) == 4 &&
+            0 <= d1 && d1 <= 255 && 0 <= d2 && d2 <= 255 &&
+            0 <= d3 && d3 <= 255 && 0 <= d4 && d4 <= 255) {
+            in.s_addr = htonl(
+                ((long) d1 << 24) | ((long) d2 << 16) |
+                ((long) d3 << 8) | ((long) d4 << 0));
+        }
+        else {
+            return 0;
+        }
+#endif
+        memcpy(pton, &in, sizeof(in));
+        return 1;
 }
 #endif
 
 int
 getaddrinfo(const char *hostname, const char *servname, const struct addrinfo *hints, struct addrinfo **res)
 {
-	struct addrinfo sentinel;
-	struct addrinfo *top = NULL;
-	struct addrinfo *cur;
-	int i, error = 0;
-	char pton[PTON_MAX];
-	struct addrinfo ai;
-	struct addrinfo *pai;
-	u_short port;
+        struct addrinfo sentinel;
+        struct addrinfo *top = NULL;
+        struct addrinfo *cur;
+        int i, error = 0;
+        char pton[PTON_MAX];
+        struct addrinfo ai;
+        struct addrinfo *pai;
+        u_short port;
 
 #ifdef FAITH
-	static int firsttime = 1;
-
-	if (firsttime) {
-		/* translator hack */
-		{
-			char *q = getenv("GAI");
-			if (q && inet_pton(AF_INET6, q, &faith_prefix) == 1)
-				translate = YES;
-		}
-		firsttime = 0;
-	}
-#endif
-
-	/* initialize file static vars */
-	sentinel.ai_next = NULL;
-	cur = &sentinel;
-	pai = &ai;
-	pai->ai_flags = 0;
-	pai->ai_family = PF_UNSPEC;
-	pai->ai_socktype = ANY;
-	pai->ai_protocol = ANY;
-	pai->ai_addrlen = 0;
-	pai->ai_canonname = NULL;
-	pai->ai_addr = NULL;
-	pai->ai_next = NULL;
-	port = ANY;
-
-	if (hostname == NULL && servname == NULL)
-		return EAI_NONAME;
-	if (hints) {
-		/* error check for hints */
-		if (hints->ai_addrlen || hints->ai_canonname ||
-		    hints->ai_addr || hints->ai_next)
-			ERR(EAI_BADHINTS); /* xxx */
-		if (hints->ai_flags & ~AI_MASK)
-			ERR(EAI_BADFLAGS);
-		switch (hints->ai_family) {
-		case PF_UNSPEC:
-		case PF_INET:
+        static int firsttime = 1;
+
+        if (firsttime) {
+                /* translator hack */
+                {
+                        char *q = getenv("GAI");
+                        if (q && inet_pton(AF_INET6, q, &faith_prefix) == 1)
+                                translate = YES;
+                }
+                firsttime = 0;
+        }
+#endif
+
+        /* initialize file static vars */
+        sentinel.ai_next = NULL;
+        cur = &sentinel;
+        pai = &ai;
+        pai->ai_flags = 0;
+        pai->ai_family = PF_UNSPEC;
+        pai->ai_socktype = ANY;
+        pai->ai_protocol = ANY;
+        pai->ai_addrlen = 0;
+        pai->ai_canonname = NULL;
+        pai->ai_addr = NULL;
+        pai->ai_next = NULL;
+        port = ANY;
+
+        if (hostname == NULL && servname == NULL)
+                return EAI_NONAME;
+        if (hints) {
+                /* error check for hints */
+                if (hints->ai_addrlen || hints->ai_canonname ||
+                    hints->ai_addr || hints->ai_next)
+                        ERR(EAI_BADHINTS); /* xxx */
+                if (hints->ai_flags & ~AI_MASK)
+                        ERR(EAI_BADFLAGS);
+                switch (hints->ai_family) {
+                case PF_UNSPEC:
+                case PF_INET:
 #ifdef INET6
-		case PF_INET6:
-#endif
-			break;
-		default:
-			ERR(EAI_FAMILY);
-		}
-		memcpy(pai, hints, sizeof(*pai));
-		switch (pai->ai_socktype) {
-		case ANY:
-			switch (pai->ai_protocol) {
-			case ANY:
-				break;
-			case IPPROTO_UDP:
-				pai->ai_socktype = SOCK_DGRAM;
-				break;
-			case IPPROTO_TCP:
-				pai->ai_socktype = SOCK_STREAM;
-				break;
-			default:
+                case PF_INET6:
+#endif
+                        break;
+                default:
+                        ERR(EAI_FAMILY);
+                }
+                memcpy(pai, hints, sizeof(*pai));
+                switch (pai->ai_socktype) {
+                case ANY:
+                        switch (pai->ai_protocol) {
+                        case ANY:
+                                break;
+                        case IPPROTO_UDP:
+                                pai->ai_socktype = SOCK_DGRAM;
+                                break;
+                        case IPPROTO_TCP:
+                                pai->ai_socktype = SOCK_STREAM;
+                                break;
+                        default:
 #if defined(SOCK_RAW)
-				pai->ai_socktype = SOCK_RAW;
+                                pai->ai_socktype = SOCK_RAW;
 #endif
-				break;
-			}
-			break;
+                                break;
+                        }
+                        break;
 #if defined(SOCK_RAW)
-		case SOCK_RAW:
-			break;
-#endif
-		case SOCK_DGRAM:
-			if (pai->ai_protocol != IPPROTO_UDP &&
-			    pai->ai_protocol != ANY)
-				ERR(EAI_BADHINTS);	/*xxx*/
-			pai->ai_protocol = IPPROTO_UDP;
-			break;
-		case SOCK_STREAM:
-			if (pai->ai_protocol != IPPROTO_TCP &&
-			    pai->ai_protocol != ANY)
-				ERR(EAI_BADHINTS);	/*xxx*/
-			pai->ai_protocol = IPPROTO_TCP;
-			break;
-		default:
-			ERR(EAI_SOCKTYPE);
-			break;
-		}
-	}
-
-	/*
-	 * service port
-	 */
-	if (servname) {
-		if (str_isnumber(servname)) {
-			if (pai->ai_socktype == ANY) {
-				/* caller accept *ANY* socktype */
-				pai->ai_socktype = SOCK_DGRAM;
-				pai->ai_protocol = IPPROTO_UDP;
-			}
-			port = htons((unsigned short)atoi(servname));
+                case SOCK_RAW:
+                        break;
+#endif
+                case SOCK_DGRAM:
+                        if (pai->ai_protocol != IPPROTO_UDP &&
+                            pai->ai_protocol != ANY)
+                                ERR(EAI_BADHINTS);	/*xxx*/
+                        pai->ai_protocol = IPPROTO_UDP;
+                        break;
+                case SOCK_STREAM:
+                        if (pai->ai_protocol != IPPROTO_TCP &&
+                            pai->ai_protocol != ANY)
+                                ERR(EAI_BADHINTS);	/*xxx*/
+                        pai->ai_protocol = IPPROTO_TCP;
+                        break;
+                default:
+                        ERR(EAI_SOCKTYPE);
+                        break;
+                }
+        }
+
+        /*
+         * service port
+         */
+        if (servname) {
+                if (str_isnumber(servname)) {
+                        if (pai->ai_socktype == ANY) {
+                                /* caller accept *ANY* socktype */
+                                pai->ai_socktype = SOCK_DGRAM;
+                                pai->ai_protocol = IPPROTO_UDP;
+                        }
+                        port = htons((unsigned short)atoi(servname));
                 } else if (pai->ai_flags & AI_NUMERICSERV) {
                         ERR(EAI_NONAME);
-		} else {
-			struct servent *sp;
-			const char *proto;
-
-			proto = NULL;
-			switch (pai->ai_socktype) {
-			case ANY:
-				proto = NULL;
-				break;
-			case SOCK_DGRAM:
-				proto = "udp";
-				break;
-			case SOCK_STREAM:
-				proto = "tcp";
-				break;
-			default:
-				fprintf(stderr, "panic!\n");
-				break;
-			}
-			if ((sp = getservbyname((char*)servname, proto)) == NULL)
-				ERR(EAI_SERVICE);
-			port = sp->s_port;
-			if (pai->ai_socktype == ANY)
-				if (strcmp(sp->s_proto, "udp") == 0) {
-					pai->ai_socktype = SOCK_DGRAM;
-					pai->ai_protocol = IPPROTO_UDP;
-				} else if (strcmp(sp->s_proto, "tcp") == 0) {
-					pai->ai_socktype = SOCK_STREAM;
-					pai->ai_protocol = IPPROTO_TCP;
-				} else
-					ERR(EAI_PROTOCOL);	/*xxx*/
-		}
-	}
-
-	/*
-	 * hostname == NULL.
-	 * passive socket -> anyaddr (0.0.0.0 or ::)
-	 * non-passive socket -> localhost (127.0.0.1 or ::1)
-	 */
-	if (hostname == NULL) {
-		const struct afd *afd;
-		int s;
-
-		for (afd = &afdl[0]; afd->a_af; afd++) {
-			if (!(pai->ai_family == PF_UNSPEC
-			   || pai->ai_family == afd->a_af)) {
-				continue;
-			}
-
-			/*
-			 * filter out AFs that are not supported by the kernel
-			 * XXX errno?
-			 */
-			s = socket(afd->a_af, SOCK_DGRAM, 0);
-			if (s < 0)
-				continue;
-
-			close(s);
-
-			if (pai->ai_flags & AI_PASSIVE) {
-				GET_AI(cur->ai_next, afd, afd->a_addrany, port);
-				/* xxx meaningless?
-				 * GET_CANONNAME(cur->ai_next, "anyaddr");
-				 */
-			} else {
-				GET_AI(cur->ai_next, afd, afd->a_loopback,
-					port);
-				/* xxx meaningless?
-				 * GET_CANONNAME(cur->ai_next, "localhost");
-				 */
-			}
-			cur = cur->ai_next;
-		}
-		top = sentinel.ai_next;
-		if (top)
-			goto good;
-		else
-			ERR(EAI_FAMILY);
-	}
-
-	/* hostname as numeric name */
-	for (i = 0; afdl[i].a_af; i++) {
-		if (inet_pton(afdl[i].a_af, hostname, pton)) {
-			u_long v4a;
+                } else {
+                        struct servent *sp;
+                        const char *proto;
+
+                        proto = NULL;
+                        switch (pai->ai_socktype) {
+                        case ANY:
+                                proto = NULL;
+                                break;
+                        case SOCK_DGRAM:
+                                proto = "udp";
+                                break;
+                        case SOCK_STREAM:
+                                proto = "tcp";
+                                break;
+                        default:
+                                fprintf(stderr, "panic!\n");
+                                break;
+                        }
+                        if ((sp = getservbyname((char*)servname, proto)) == NULL)
+                                ERR(EAI_SERVICE);
+                        port = sp->s_port;
+                        if (pai->ai_socktype == ANY)
+                                if (strcmp(sp->s_proto, "udp") == 0) {
+                                        pai->ai_socktype = SOCK_DGRAM;
+                                        pai->ai_protocol = IPPROTO_UDP;
+                                } else if (strcmp(sp->s_proto, "tcp") == 0) {
+                                        pai->ai_socktype = SOCK_STREAM;
+                                        pai->ai_protocol = IPPROTO_TCP;
+                                } else
+                                        ERR(EAI_PROTOCOL);	/*xxx*/
+                }
+        }
+
+        /*
+         * hostname == NULL.
+         * passive socket -> anyaddr (0.0.0.0 or ::)
+         * non-passive socket -> localhost (127.0.0.1 or ::1)
+         */
+        if (hostname == NULL) {
+                const struct afd *afd;
+                int s;
+
+                for (afd = &afdl[0]; afd->a_af; afd++) {
+                        if (!(pai->ai_family == PF_UNSPEC
+                           || pai->ai_family == afd->a_af)) {
+                                continue;
+                        }
+
+                        /*
+                         * filter out AFs that are not supported by the kernel
+                         * XXX errno?
+                         */
+                        s = socket(afd->a_af, SOCK_DGRAM, 0);
+                        if (s < 0)
+                                continue;
+
+                        close(s);
+
+                        if (pai->ai_flags & AI_PASSIVE) {
+                                GET_AI(cur->ai_next, afd, afd->a_addrany, port);
+                                /* xxx meaningless?
+                                 * GET_CANONNAME(cur->ai_next, "anyaddr");
+                                 */
+                        } else {
+                                GET_AI(cur->ai_next, afd, afd->a_loopback,
+                                        port);
+                                /* xxx meaningless?
+                                 * GET_CANONNAME(cur->ai_next, "localhost");
+                                 */
+                        }
+                        cur = cur->ai_next;
+                }
+                top = sentinel.ai_next;
+                if (top)
+                        goto good;
+                else
+                        ERR(EAI_FAMILY);
+        }
+
+        /* hostname as numeric name */
+        for (i = 0; afdl[i].a_af; i++) {
+                if (inet_pton(afdl[i].a_af, hostname, pton)) {
+                        u_long v4a;
 #ifdef INET6
-			u_char pfx;
-#endif
-
-			switch (afdl[i].a_af) {
-			case AF_INET:
-				v4a = ((struct in_addr *)pton)->s_addr;
-				if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a))
-					pai->ai_flags &= ~AI_CANONNAME;
-				v4a >>= IN_CLASSA_NSHIFT;
-				if (v4a == 0 || v4a == IN_LOOPBACKNET)
-					pai->ai_flags &= ~AI_CANONNAME;
-				break;
+                        u_char pfx;
+#endif
+
+                        switch (afdl[i].a_af) {
+                        case AF_INET:
+                                v4a = ((struct in_addr *)pton)->s_addr;
+                                if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a))
+                                        pai->ai_flags &= ~AI_CANONNAME;
+                                v4a >>= IN_CLASSA_NSHIFT;
+                                if (v4a == 0 || v4a == IN_LOOPBACKNET)
+                                        pai->ai_flags &= ~AI_CANONNAME;
+                                break;
 #ifdef INET6
-			case AF_INET6:
-				pfx = ((struct in6_addr *)pton)->s6_addr[0];
-				if (pfx == 0 || pfx == 0xfe || pfx == 0xff)
-					pai->ai_flags &= ~AI_CANONNAME;
-				break;
-#endif
-			}
-
-			if (pai->ai_family == afdl[i].a_af ||
-			    pai->ai_family == PF_UNSPEC) {
-				if (! (pai->ai_flags & AI_CANONNAME)) {
-					GET_AI(top, &afdl[i], pton, port);
-					goto good;
-				}
-				/*
-				 * if AI_CANONNAME and if reverse lookup
-				 * fail, return ai anyway to pacify
-				 * calling application.
-				 *
-				 * XXX getaddrinfo() is a name->address
-				 * translation function, and it looks strange
-				 * that we do addr->name translation here.
-				 */
-				get_name(pton, &afdl[i], &top, pton, pai, port);
-				goto good;
-			} else
-				ERR(EAI_FAMILY);	/*xxx*/
-		}
-	}
-
-	if (pai->ai_flags & AI_NUMERICHOST)
-		ERR(EAI_NONAME);
-
-	/* hostname as alphabetical name */
-	error = get_addr(hostname, pai->ai_family, &top, pai, port);
-	if (error == 0) {
-		if (top) {
+                        case AF_INET6:
+                                pfx = ((struct in6_addr *)pton)->s6_addr[0];
+                                if (pfx == 0 || pfx == 0xfe || pfx == 0xff)
+                                        pai->ai_flags &= ~AI_CANONNAME;
+                                break;
+#endif
+                        }
+
+                        if (pai->ai_family == afdl[i].a_af ||
+                            pai->ai_family == PF_UNSPEC) {
+                                if (! (pai->ai_flags & AI_CANONNAME)) {
+                                        GET_AI(top, &afdl[i], pton, port);
+                                        goto good;
+                                }
+                                /*
+                                 * if AI_CANONNAME and if reverse lookup
+                                 * fail, return ai anyway to pacify
+                                 * calling application.
+                                 *
+                                 * XXX getaddrinfo() is a name->address
+                                 * translation function, and it looks strange
+                                 * that we do addr->name translation here.
+                                 */
+                                get_name(pton, &afdl[i], &top, pton, pai, port);
+                                goto good;
+                        } else
+                                ERR(EAI_FAMILY);	/*xxx*/
+                }
+        }
+
+        if (pai->ai_flags & AI_NUMERICHOST)
+                ERR(EAI_NONAME);
+
+        /* hostname as alphabetical name */
+        error = get_addr(hostname, pai->ai_family, &top, pai, port);
+        if (error == 0) {
+                if (top) {
  good:
-			*res = top;
-			return SUCCESS;
-		} else
-			error = EAI_FAIL;
-	}
+                        *res = top;
+                        return SUCCESS;
+                } else
+                        error = EAI_FAIL;
+        }
  free:
-	if (top)
-		freeaddrinfo(top);
+        if (top)
+                freeaddrinfo(top);
  bad:
-	*res = NULL;
-	return error;
+        *res = NULL;
+        return error;
 }
 
 static int
 get_name(const char *addr, const struct afd *afd, struct addrinfo **res, char *numaddr, struct addrinfo *pai, int port0)
 {
-	u_short port = port0 & 0xffff;
-	struct hostent *hp;
-	struct addrinfo *cur;
-	int error = 0;
+        u_short port = port0 & 0xffff;
+        struct hostent *hp;
+        struct addrinfo *cur;
+        int error = 0;
 #ifdef INET6
-	int h_error;
+        int h_error;
 #endif
 
 #ifdef INET6
-	hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error);
+        hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error);
 #else
-	hp = gethostbyaddr((char*)addr, afd->a_addrlen, AF_INET);
+        hp = gethostbyaddr((char*)addr, afd->a_addrlen, AF_INET);
 #endif
-	if (hp && hp->h_name && hp->h_name[0] && hp->h_addr_list[0]) {
-		GET_AI(cur, afd, hp->h_addr_list[0], port);
-		GET_CANONNAME(cur, hp->h_name);
-	} else
-		GET_AI(cur, afd, numaddr, port);
+        if (hp && hp->h_name && hp->h_name[0] && hp->h_addr_list[0]) {
+                GET_AI(cur, afd, hp->h_addr_list[0], port);
+                GET_CANONNAME(cur, hp->h_name);
+        } else
+                GET_AI(cur, afd, numaddr, port);
 
 #ifdef INET6
-	if (hp)
-		freehostent(hp);
+        if (hp)
+                freehostent(hp);
 #endif
-	*res = cur;
-	return SUCCESS;
+        *res = cur;
+        return SUCCESS;
  free:
-	if (cur)
-		freeaddrinfo(cur);
+        if (cur)
+                freeaddrinfo(cur);
 #ifdef INET6
-	if (hp)
-		freehostent(hp);
+        if (hp)
+                freehostent(hp);
 #endif
  /* bad: */
-	*res = NULL;
-	return error;
+        *res = NULL;
+        return error;
 }
 
 static int
 get_addr(const char *hostname, int af, struct addrinfo **res, struct addrinfo *pai, int port0)
 {
-	u_short port = port0 & 0xffff;
-	struct addrinfo sentinel;
-	struct hostent *hp;
-	struct addrinfo *top, *cur;
-	const struct afd *afd;
-	int i, error = 0, h_error;
-	char *ap;
-
-	top = NULL;
-	sentinel.ai_next = NULL;
-	cur = &sentinel;
+        u_short port = port0 & 0xffff;
+        struct addrinfo sentinel;
+        struct hostent *hp;
+        struct addrinfo *top, *cur;
+        const struct afd *afd;
+        int i, error = 0, h_error;
+        char *ap;
+
+        top = NULL;
+        sentinel.ai_next = NULL;
+        cur = &sentinel;
 #ifdef INET6
-	if (af == AF_UNSPEC) {
-		hp = getipnodebyname(hostname, AF_INET6,
-				AI_ADDRCONFIG|AI_ALL|AI_V4MAPPED, &h_error);
-	} else
-		hp = getipnodebyname(hostname, af, AI_ADDRCONFIG, &h_error);
+        if (af == AF_UNSPEC) {
+                hp = getipnodebyname(hostname, AF_INET6,
+                                AI_ADDRCONFIG|AI_ALL|AI_V4MAPPED, &h_error);
+        } else
+                hp = getipnodebyname(hostname, af, AI_ADDRCONFIG, &h_error);
 #else
-	if (strlen(hostname) >= NI_MAXHOST) ERR(EAI_NODATA);
-	hp = gethostbyname((char*)hostname);
-	h_error = h_errno;
-#endif
-	if (hp == NULL) {
-		switch (h_error) {
-		case HOST_NOT_FOUND:
-		case NO_DATA:
-			error = EAI_NODATA;
-			break;
-		case TRY_AGAIN:
-			error = EAI_AGAIN;
-			break;
-		case NO_RECOVERY:
-		default:
-			error = EAI_FAIL;
-			break;
-		}
-		goto bad;
-	}
-
-	if ((hp->h_name == NULL) || (hp->h_name[0] == 0) ||
-	    (hp->h_addr_list[0] == NULL))
-		ERR(EAI_FAIL);
-
-	for (i = 0; (ap = hp->h_addr_list[i]) != NULL; i++) {
-		switch (af) {
+        if (strlen(hostname) >= NI_MAXHOST) ERR(EAI_NODATA);
+        hp = gethostbyname((char*)hostname);
+        h_error = h_errno;
+#endif
+        if (hp == NULL) {
+                switch (h_error) {
+                case HOST_NOT_FOUND:
+                case NO_DATA:
+                        error = EAI_NODATA;
+                        break;
+                case TRY_AGAIN:
+                        error = EAI_AGAIN;
+                        break;
+                case NO_RECOVERY:
+                default:
+                        error = EAI_FAIL;
+                        break;
+                }
+                goto bad;
+        }
+
+        if ((hp->h_name == NULL) || (hp->h_name[0] == 0) ||
+            (hp->h_addr_list[0] == NULL))
+                ERR(EAI_FAIL);
+
+        for (i = 0; (ap = hp->h_addr_list[i]) != NULL; i++) {
+                switch (af) {
 #ifdef INET6
-		case AF_INET6:
-			afd = &afdl[N_INET6];
-			break;
+                case AF_INET6:
+                        afd = &afdl[N_INET6];
+                        break;
 #endif
 #ifndef INET6
-		default:	/* AF_UNSPEC */
+                default:	/* AF_UNSPEC */
 #endif
-		case AF_INET:
-			afd = &afdl[N_INET];
-			break;
+                case AF_INET:
+                        afd = &afdl[N_INET];
+                        break;
 #ifdef INET6
-		default:	/* AF_UNSPEC */
-			if (IN6_IS_ADDR_V4MAPPED((struct in6_addr *)ap)) {
-				ap += sizeof(struct in6_addr) -
-					sizeof(struct in_addr);
-				afd = &afdl[N_INET];
-			} else
-				afd = &afdl[N_INET6];
-			break;
-#endif
-		}
+                default:	/* AF_UNSPEC */
+                        if (IN6_IS_ADDR_V4MAPPED((struct in6_addr *)ap)) {
+                                ap += sizeof(struct in6_addr) -
+                                        sizeof(struct in_addr);
+                                afd = &afdl[N_INET];
+                        } else
+                                afd = &afdl[N_INET6];
+                        break;
+#endif
+                }
 #ifdef FAITH
-		if (translate && afd->a_af == AF_INET) {
-			struct in6_addr *in6;
-
-			GET_AI(cur->ai_next, &afdl[N_INET6], ap, port);
-			in6 = &((struct sockaddr_in6 *)cur->ai_next->ai_addr)->sin6_addr;
-			memcpy(&in6->s6_addr, &faith_prefix,
-			       sizeof(struct in6_addr) - sizeof(struct in_addr));
-			memcpy(&in6->s6_addr + sizeof(struct in_addr), ap,
-			       sizeof(struct in_addr));
-		} else
+                if (translate && afd->a_af == AF_INET) {
+                        struct in6_addr *in6;
+
+                        GET_AI(cur->ai_next, &afdl[N_INET6], ap, port);
+                        in6 = &((struct sockaddr_in6 *)cur->ai_next->ai_addr)->sin6_addr;
+                        memcpy(&in6->s6_addr, &faith_prefix,
+                               sizeof(struct in6_addr) - sizeof(struct in_addr));
+                        memcpy(&in6->s6_addr + sizeof(struct in_addr), ap,
+                               sizeof(struct in_addr));
+                } else
 #endif /* FAITH */
-		GET_AI(cur->ai_next, afd, ap, port);
-		if (cur == &sentinel) {
-			top = cur->ai_next;
-			GET_CANONNAME(top, hp->h_name);
-		}
-		cur = cur->ai_next;
-	}
+                GET_AI(cur->ai_next, afd, ap, port);
+                if (cur == &sentinel) {
+                        top = cur->ai_next;
+                        GET_CANONNAME(top, hp->h_name);
+                }
+                cur = cur->ai_next;
+        }
 #ifdef INET6
-	freehostent(hp);
+        freehostent(hp);
 #endif
-	*res = top;
-	return SUCCESS;
+        *res = top;
+        return SUCCESS;
  free:
-	if (top)
-		freeaddrinfo(top);
+        if (top)
+                freeaddrinfo(top);
 #ifdef INET6
-	if (hp)
-		freehostent(hp);
+        if (hp)
+                freehostent(hp);
 #endif
  bad:
-	*res = NULL;
-	return error;
+        *res = NULL;
+        return error;
 }
diff --git a/ext/socket/getnameinfo.c b/ext/socket/getnameinfo.c
index 94a5eb9439..ae5284fab6 100644
--- a/ext/socket/getnameinfo.c
+++ b/ext/socket/getnameinfo.c
@@ -84,30 +84,30 @@ typedef int socklen_t;
 #define NO  0
 
 struct sockinet {
-	u_char	si_len;
-	u_char	si_family;
-	u_short	si_port;
+        u_char	si_len;
+        u_char	si_family;
+        u_short	si_port;
 };
 
 static struct afd {
-	int a_af;
-	int a_addrlen;
-	int a_socklen;
-	int a_off;
+        int a_af;
+        int a_addrlen;
+        int a_socklen;
+        int a_off;
 } afdl [] = {
 #ifdef INET6
 #define N_INET6 0
-	{PF_INET6, sizeof(struct in6_addr),
-	 sizeof(struct sockaddr_in6),
-	 offsetof(struct sockaddr_in6, sin6_addr)},
+        {PF_INET6, sizeof(struct in6_addr),
+         sizeof(struct sockaddr_in6),
+         offsetof(struct sockaddr_in6, sin6_addr)},
 #define N_INET  1
 #else
 #define N_INET  0
 #endif
-	{PF_INET, sizeof(struct in_addr),
-	 sizeof(struct sockaddr_in),
-	 offsetof(struct sockaddr_in, sin_addr)},
-	{0, 0, 0, 0},
+        {PF_INET, sizeof(struct in_addr),
+         sizeof(struct sockaddr_in),
+         offsetof(struct sockaddr_in, sin_addr)},
+        {0, 0, 0, 0},
 };
 
 #define ENI_NOSOCKET 	0
@@ -121,123 +121,123 @@ static struct afd {
 int
 getnameinfo(const struct sockaddr *sa, socklen_t salen, char *host, socklen_t hostlen, char *serv, socklen_t servlen, int flags)
 {
-	struct afd *afd;
-	struct hostent *hp;
-	u_short port;
-	int family, len, i;
-	char *addr, *p;
-	u_long v4a;
+        struct afd *afd;
+        struct hostent *hp;
+        u_short port;
+        int family, len, i;
+        char *addr, *p;
+        u_long v4a;
 #ifdef INET6
-	u_char pfx;
+        u_char pfx;
 #endif
-	int h_error;
-	char numserv[512];
-	char numaddr[512];
+        int h_error;
+        char numserv[512];
+        char numaddr[512];
 
-	if (sa == NULL)
-		return ENI_NOSOCKET;
+        if (sa == NULL)
+                return ENI_NOSOCKET;
 
-	if (!VALIDATE_SOCKLEN(sa, salen)) return ENI_SALEN;
+        if (!VALIDATE_SOCKLEN(sa, salen)) return ENI_SALEN;
         len = salen;
 
-	family = sa->sa_family;
-	for (i = 0; afdl[i].a_af; i++)
-		if (afdl[i].a_af == family) {
-			afd = &afdl[i];
-			goto found;
-		}
-	return ENI_FAMILY;
+        family = sa->sa_family;
+        for (i = 0; afdl[i].a_af; i++)
+                if (afdl[i].a_af == family) {
+                        afd = &afdl[i];
+                        goto found;
+                }
+        return ENI_FAMILY;
 
  found:
-	if (len != afd->a_socklen) return ENI_SALEN;
-
-	port = ((struct sockinet *)sa)->si_port; /* network byte order */
-	addr = (char *)sa + afd->a_off;
-
-	if (serv == NULL || servlen == 0) {
-		/* what we should do? */
-	} else if (flags & NI_NUMERICSERV) {
-		snprintf(numserv, sizeof(numserv), "%d", ntohs(port));
-		if (strlen(numserv) + 1 > servlen)
-			return ENI_MEMORY;
-		strcpy(serv, numserv);
-	} else {
+        if (len != afd->a_socklen) return ENI_SALEN;
+
+        port = ((struct sockinet *)sa)->si_port; /* network byte order */
+        addr = (char *)sa + afd->a_off;
+
+        if (serv == NULL || servlen == 0) {
+                /* what we should do? */
+        } else if (flags & NI_NUMERICSERV) {
+                snprintf(numserv, sizeof(numserv), "%d", ntohs(port));
+                if (strlen(numserv) + 1 > servlen)
+                        return ENI_MEMORY;
+                strcpy(serv, numserv);
+        } else {
 #if defined(HAVE_GETSERVBYPORT)
-		struct servent *sp = getservbyport(port, (flags & NI_DGRAM) ? "udp" : "tcp");
-		if (sp) {
-			if (strlen(sp->s_name) + 1 > servlen)
-				return ENI_MEMORY;
-			strcpy(serv, sp->s_name);
-		} else
-			return ENI_NOSERVNAME;
+                struct servent *sp = getservbyport(port, (flags & NI_DGRAM) ? "udp" : "tcp");
+                if (sp) {
+                        if (strlen(sp->s_name) + 1 > servlen)
+                                return ENI_MEMORY;
+                        strcpy(serv, sp->s_name);
+                } else
+                        return ENI_NOSERVNAME;
 #else
-		return ENI_NOSERVNAME;
-#endif
-	}
-
-	switch (sa->sa_family) {
-	case AF_INET:
-		v4a = ntohl(((struct sockaddr_in *)sa)->sin_addr.s_addr);
-		if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a))
-			flags |= NI_NUMERICHOST;
-		v4a >>= IN_CLASSA_NSHIFT;
-		if (v4a == 0)
-			flags |= NI_NUMERICHOST;
-		break;
+                return ENI_NOSERVNAME;
+#endif
+        }
+
+        switch (sa->sa_family) {
+        case AF_INET:
+                v4a = ntohl(((struct sockaddr_in *)sa)->sin_addr.s_addr);
+                if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a))
+                        flags |= NI_NUMERICHOST;
+                v4a >>= IN_CLASSA_NSHIFT;
+                if (v4a == 0)
+                        flags |= NI_NUMERICHOST;
+                break;
 #ifdef INET6
-	case AF_INET6:
+        case AF_INET6:
 #ifdef HAVE_ADDR8
-		pfx = ((struct sockaddr_in6 *)sa)->sin6_addr.s6_addr8[0];
+                pfx = ((struct sockaddr_in6 *)sa)->sin6_addr.s6_addr8[0];
 #else
-		pfx = ((struct sockaddr_in6 *)sa)->sin6_addr.s6_addr[0];
-#endif
-		if (pfx == 0 || pfx == 0xfe || pfx == 0xff)
-			flags |= NI_NUMERICHOST;
-		break;
-#endif
-	}
-	if (host == NULL || hostlen == 0) {
-		/* what should we do? */
-	} else if (flags & NI_NUMERICHOST) {
-		if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))
-		    == NULL)
-			return ENI_SYSTEM;
-		if (strlen(numaddr) > hostlen)
-			return ENI_MEMORY;
-		strcpy(host, numaddr);
-	} else {
+                pfx = ((struct sockaddr_in6 *)sa)->sin6_addr.s6_addr[0];
+#endif
+                if (pfx == 0 || pfx == 0xfe || pfx == 0xff)
+                        flags |= NI_NUMERICHOST;
+                break;
+#endif
+        }
+        if (host == NULL || hostlen == 0) {
+                /* what should we do? */
+        } else if (flags & NI_NUMERICHOST) {
+                if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))
+                    == NULL)
+                        return ENI_SYSTEM;
+                if (strlen(numaddr) > hostlen)
+                        return ENI_MEMORY;
+                strcpy(host, numaddr);
+        } else {
 #ifdef INET6
-		hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error);
+                hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error);
 #else
-		hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af);
-		h_error = h_errno;
+                hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af);
+                h_error = h_errno;
 #endif
 
-		if (hp) {
-			if (flags & NI_NOFQDN) {
-				p = strchr(hp->h_name, '.');
-				if (p) *p = '\0';
-			}
-			if (strlen(hp->h_name) + 1 > hostlen) {
+                if (hp) {
+                        if (flags & NI_NOFQDN) {
+                                p = strchr(hp->h_name, '.');
+                                if (p) *p = '\0';
+                        }
+                        if (strlen(hp->h_name) + 1 > hostlen) {
 #ifdef INET6
-				freehostent(hp);
+                                freehostent(hp);
 #endif
-				return ENI_MEMORY;
-			}
-			strcpy(host, hp->h_name);
+                                return ENI_MEMORY;
+                        }
+                        strcpy(host, hp->h_name);
 #ifdef INET6
-			freehostent(hp);
-#endif
-		} else {
-			if (flags & NI_NAMEREQD)
-				return ENI_NOHOSTNAME;
-			if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))
-			    == NULL)
-				return ENI_NOHOSTNAME;
-			if (strlen(numaddr) > hostlen)
-				return ENI_MEMORY;
-			strcpy(host, numaddr);
-		}
-	}
-	return SUCCESS;
+                        freehostent(hp);
+#endif
+                } else {
+                        if (flags & NI_NAMEREQD)
+                                return ENI_NOHOSTNAME;
+                        if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))
+                            == NULL)
+                                return ENI_NOHOSTNAME;
+                        if (strlen(numaddr) > hostlen)
+                                return ENI_MEMORY;
+                        strcpy(host, numaddr);
+                }
+        }
+        return SUCCESS;
 }
diff --git a/ext/socket/ifaddr.c b/ext/socket/ifaddr.c
index 1da259bd6f..ab163dcc8f 100644
--- a/ext/socket/ifaddr.c
+++ b/ext/socket/ifaddr.c
@@ -104,7 +104,7 @@ rsock_getifaddrs(void)
         rb_sys_fail("getifaddrs");
 
     if (!ifaddrs) {
-	return rb_ary_new();
+        return rb_ary_new();
     }
 
     numifaddrs = 0;
@@ -128,9 +128,9 @@ rsock_getifaddrs(void)
     result = rb_ary_new2(numifaddrs);
     rb_ary_push(result, addr);
     for (i = 1; i < numifaddrs; i++) {
-	addr = TypedData_Wrap_Struct(rb_cSockIfaddr, &ifaddr_type, &root->ary[i]);
-	root->refcount++;
-	rb_ary_push(result, addr);
+        addr = TypedData_Wrap_Struct(rb_cSockIfaddr, &ifaddr_type, &root->ary[i]);
+        root->refcount++;
+        rb_ary_push(result, addr);
     }
 
     return result;
diff --git a/ext/socket/init.c b/ext/socket/init.c
index 359696e626..557d4374a5 100644
--- a/ext/socket/init.c
+++ b/ext/socket/init.c
@@ -41,7 +41,7 @@ rsock_raise_socket_error(const char *reason, int error)
 #ifdef EAI_SYSTEM
     int e;
     if (error == EAI_SYSTEM && (e = errno) != 0)
-	rb_syserr_fail(e, reason);
+        rb_syserr_fail(e, reason);
 #endif
 #ifdef _WIN32
     rb_encoding *enc = rb_default_internal_encoding();
@@ -71,7 +71,7 @@ rsock_init_sock(VALUE sock, int fd)
     fp->mode = FMODE_READWRITE|FMODE_DUPLEX;
     rb_io_ascii8bit_binmode(sock);
     if (rsock_do_not_reverse_lookup) {
-	fp->mode |= FMODE_NOREVLOOKUP;
+        fp->mode |= FMODE_NOREVLOOKUP;
     }
     rb_io_synchronized(fp);
 
@@ -85,7 +85,7 @@ rsock_sendto_blocking(void *data)
     VALUE mesg = arg->mesg;
     ssize_t ret;
     do_write_retry(sendto(arg->fd, RSTRING_PTR(mesg), RSTRING_LEN(mesg),
-			  arg->flags, arg->to, arg->tolen));
+                          arg->flags, arg->to, arg->tolen));
     return (VALUE)ret;
 }
 
@@ -96,7 +96,7 @@ rsock_send_blocking(void *data)
     VALUE mesg = arg->mesg;
     ssize_t ret;
     do_write_retry(send(arg->fd, RSTRING_PTR(mesg), RSTRING_LEN(mesg),
-			arg->flags));
+                        arg->flags));
     return (VALUE)ret;
 }
 
@@ -132,9 +132,9 @@ rsock_strbuf(VALUE str, long buflen)
     StringValue(str);
     len = RSTRING_LEN(str);
     if (len >= buflen) {
-	rb_str_modify(str);
+        rb_str_modify(str);
     } else {
-	rb_str_modify_expand(str, buflen - len);
+        rb_str_modify_expand(str, buflen - len);
     }
     return str;
 }
@@ -189,7 +189,7 @@ rsock_s_recvfrom(VALUE socket, int argc, VALUE *argv, enum sock_recv_type from)
 
         if (slen >= 0) break;
 
-        if (!rb_io_maybe_wait_readable(errno, socket, Qnil))
+        if (!rb_io_maybe_wait_readable(errno, socket, RUBY_IO_TIMEOUT_DEFAULT))
             rb_sys_fail("recvfrom(2)");
     }
 
@@ -197,32 +197,32 @@ rsock_s_recvfrom(VALUE socket, int argc, VALUE *argv, enum sock_recv_type from)
     rb_str_set_len(str, slen);
     switch (from) {
       case RECV_RECV:
-	return str;
+        return str;
       case RECV_IP:
 #if 0
-	if (arg.alen != sizeof(struct sockaddr_in)) {
-	    rb_raise(rb_eTypeError, "sockaddr size differs - should not happen");
-	}
+        if (arg.alen != sizeof(struct sockaddr_in)) {
+            rb_raise(rb_eTypeError, "sockaddr size differs - should not happen");
+        }
 #endif
-	if (arg.alen && arg.alen != sizeof(arg.buf)) /* OSX doesn't return a from result for connection-oriented sockets */
-	    return rb_assoc_new(str, rsock_ipaddr(&arg.buf.addr, arg.alen, fptr->mode & FMODE_NOREVLOOKUP));
-	else
-	    return rb_assoc_new(str, Qnil);
+        if (arg.alen && arg.alen != sizeof(arg.buf)) /* OSX doesn't return a from result for connection-oriented sockets */
+            return rb_assoc_new(str, rsock_ipaddr(&arg.buf.addr, arg.alen, fptr->mode & FMODE_NOREVLOOKUP));
+        else
+            return rb_assoc_new(str, Qnil);
 
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
       case RECV_UNIX:
         return rb_assoc_new(str, rsock_unixaddr(&arg.buf.un, arg.alen));
 #endif
       case RECV_SOCKET:
-	return rb_assoc_new(str, rsock_io_socket_addrinfo(socket, &arg.buf.addr, arg.alen));
+        return rb_assoc_new(str, rsock_io_socket_addrinfo(socket, &arg.buf.addr, arg.alen));
       default:
-	rb_bug("rsock_s_recvfrom called with bad value");
+        rb_bug("rsock_s_recvfrom called with bad value");
     }
 }
 
 VALUE
 rsock_s_recvfrom_nonblock(VALUE sock, VALUE len, VALUE flg, VALUE str,
-			  VALUE ex, enum sock_recv_type from)
+                          VALUE ex, enum sock_recv_type from)
 {
     rb_io_t *fptr;
     union_sockaddr buf;
@@ -245,14 +245,14 @@ rsock_s_recvfrom_nonblock(VALUE sock, VALUE len, VALUE flg, VALUE str,
 
     GetOpenFile(sock, fptr);
     if (rb_io_read_pending(fptr)) {
-	rb_raise(rb_eIOError, "recvfrom for buffered IO");
+        rb_raise(rb_eIOError, "recvfrom for buffered IO");
     }
     fd = fptr->fd;
 
     rb_io_check_closed(fptr);
 
     if (!MSG_DONTWAIT_RELIABLE)
-	rb_io_set_nonblock(fptr);
+        rb_io_set_nonblock(fptr);
 
     len0 = alen;
     slen = recvfrom(fd, RSTRING_PTR(str), buflen, flags, &buf.addr, &alen);
@@ -260,20 +260,20 @@ rsock_s_recvfrom_nonblock(VALUE sock, VALUE len, VALUE flg, VALUE str,
         alen = len0;
 
     if (slen < 0) {
-	int e = errno;
-	switch (e) {
-	  case EAGAIN:
+        int e = errno;
+        switch (e) {
+          case EAGAIN:
 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
-	  case EWOULDBLOCK:
+          case EWOULDBLOCK:
 #endif
             if (ex == Qfalse)
-		return sym_wait_readable;
+                return sym_wait_readable;
             rb_readwrite_syserr_fail(RB_IO_WAIT_READABLE, e, "recvfrom(2) would block");
-	}
-	rb_syserr_fail(e, "recvfrom(2)");
+        }
+        rb_syserr_fail(e, "recvfrom(2)");
     }
     if (slen != RSTRING_LEN(str)) {
-	rb_str_set_len(str, slen);
+        rb_str_set_len(str, slen);
     }
     switch (from) {
       case RECV_RECV:
@@ -324,31 +324,31 @@ rsock_read_nonblock(VALUE sock, VALUE length, VALUE buf, VALUE ex)
     GetOpenFile(sock, fptr);
 
     if (len == 0) {
-	rb_str_set_len(str, 0);
-	return str;
+        rb_str_set_len(str, 0);
+        return str;
     }
 
     ptr = RSTRING_PTR(str);
     n = read_buffered_data(ptr, len, fptr);
     if (n <= 0) {
-	n = (long)recv(fptr->fd, ptr, len, MSG_DONTWAIT);
-	if (n < 0) {
-	    int e = errno;
-	    if ((e == EWOULDBLOCK || e == EAGAIN)) {
-		if (ex == Qfalse) return sym_wait_readable;
-		rb_readwrite_syserr_fail(RB_IO_WAIT_READABLE,
-					 e, "read would block");
-	    }
-	    rb_syserr_fail_path(e, fptr->pathv);
-	}
+        n = (long)recv(fptr->fd, ptr, len, MSG_DONTWAIT);
+        if (n < 0) {
+            int e = errno;
+            if ((e == EWOULDBLOCK || e == EAGAIN)) {
+                if (ex == Qfalse) return sym_wait_readable;
+                rb_readwrite_syserr_fail(RB_IO_WAIT_READABLE,
+                                         e, "read would block");
+            }
+            rb_syserr_fail_path(e, fptr->pathv);
+        }
     }
     if (n != RSTRING_LEN(str)) {
-	rb_str_modify(str);
-	rb_str_set_len(str, n);
+        rb_str_modify(str);
+        rb_str_set_len(str, n);
     }
     if (n == 0) {
-	if (ex == Qfalse) return Qnil;
-	rb_eof_error();
+        if (ex == Qfalse) return Qnil;
+        rb_eof_error();
     }
 
     return str;
@@ -362,7 +362,7 @@ rsock_write_nonblock(VALUE sock, VALUE str, VALUE ex)
     long n;
 
     if (!RB_TYPE_P(str, T_STRING))
-	str = rb_obj_as_string(str);
+        str = rb_obj_as_string(str);
 
     sock = rb_io_get_write_io(sock);
     GetOpenFile(sock, fptr);
@@ -374,7 +374,7 @@ rsock_write_nonblock(VALUE sock, VALUE str, VALUE ex)
      * are not userspace-buffered in Ruby by default.
      */
     if (fptr->wbuf.len > 0) {
-	rb_io_flush(sock);
+        rb_io_flush(sock);
     }
 
 #ifdef __APPLE__
@@ -382,19 +382,19 @@ rsock_write_nonblock(VALUE sock, VALUE str, VALUE ex)
 #endif
     n = (long)send(fptr->fd, RSTRING_PTR(str), RSTRING_LEN(str), MSG_DONTWAIT);
     if (n < 0) {
-	int e = errno;
+        int e = errno;
 
 #ifdef __APPLE__
-	if (e == EPROTOTYPE) {
-	    goto again;
-	}
-#endif
-	if (e == EWOULDBLOCK || e == EAGAIN) {
-	    if (ex == Qfalse) return sym_wait_writable;
-	    rb_readwrite_syserr_fail(RB_IO_WAIT_WRITABLE, e,
-				    "write would block");
-	}
-	rb_syserr_fail_path(e, fptr->pathv);
+        if (e == EPROTOTYPE) {
+            goto again;
+        }
+#endif
+        if (e == EWOULDBLOCK || e == EAGAIN) {
+            if (ex == Qfalse) return sym_wait_writable;
+            rb_readwrite_syserr_fail(RB_IO_WAIT_WRITABLE, e,
+                                    "write would block");
+        }
+        rb_syserr_fail_path(e, fptr->pathv);
     }
 
     return LONG2FIX(n);
@@ -497,11 +497,11 @@ wait_connectable(int fd, struct timeval *timeout)
        * interrupted connect()
        */
 
-	/* when the connection timed out, no errno is set and revents is 0. */
-	if (timeout && revents == 0) {
-	    errno = ETIMEDOUT;
-	    return -1;
-	}
+        /* when the connection timed out, no errno is set and revents is 0. */
+        if (timeout && revents == 0) {
+            errno = ETIMEDOUT;
+            return -1;
+        }
       case EINTR:
 #ifdef ERESTART
       case ERESTART:
@@ -516,7 +516,7 @@ wait_connectable(int fd, struct timeval *timeout)
 #ifdef EISCONN
       case EISCONN:
 #endif
-	return 0; /* success */
+        return 0; /* success */
       default:
         /* likely (but not limited to): ECONNREFUSED, ETIMEDOUT, EHOSTUNREACH */
         errno = sockerr;
@@ -634,27 +634,27 @@ cloexec_accept(int socket, struct sockaddr *address, socklen_t *address_len)
 
 VALUE
 rsock_s_accept_nonblock(VALUE klass, VALUE ex, rb_io_t *fptr,
-			struct sockaddr *sockaddr, socklen_t *len)
+                        struct sockaddr *sockaddr, socklen_t *len)
 {
     int fd2;
 
     rb_io_set_nonblock(fptr);
     fd2 = cloexec_accept(fptr->fd, (struct sockaddr*)sockaddr, len);
     if (fd2 < 0) {
-	int e = errno;
-	switch (e) {
-	  case EAGAIN:
+        int e = errno;
+        switch (e) {
+          case EAGAIN:
 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
-	  case EWOULDBLOCK:
+          case EWOULDBLOCK:
 #endif
-	  case ECONNABORTED:
+          case ECONNABORTED:
 #if defined EPROTO
-	  case EPROTO:
+          case EPROTO:
 #endif
             if (ex == Qfalse)
-		return sym_wait_readable;
+                return sym_wait_readable;
             rb_readwrite_syserr_fail(RB_IO_WAIT_READABLE, e, "accept(2) would block");
-	}
+        }
         rb_syserr_fail(e, "accept(2)");
     }
     rb_update_max_fd(fd2);
@@ -705,7 +705,7 @@ rsock_s_accept(VALUE klass, VALUE io, struct sockaddr *sockaddr, socklen_t *len)
             retry = 1;
             goto retry;
           default:
-            if (!rb_io_maybe_wait_readable(error, io, Qnil)) break;
+            if (!rb_io_maybe_wait_readable(error, io, RUBY_IO_TIMEOUT_DEFAULT)) break;
             retry = 0;
             goto retry;
         }
@@ -730,11 +730,11 @@ rsock_getfamily(rb_io_t *fptr)
     if (cached) {
         switch (cached) {
 #ifdef AF_UNIX
-	    case FMODE_UNIX: return AF_UNIX;
+            case FMODE_UNIX: return AF_UNIX;
 #endif
-	    case FMODE_INET: return AF_INET;
-	    case FMODE_INET6: return AF_INET6;
-	}
+            case FMODE_INET: return AF_INET;
+            case FMODE_INET6: return AF_INET6;
+        }
     }
 
     ss.addr.sa_family = AF_UNSPEC;
diff --git a/ext/socket/ipsocket.c b/ext/socket/ipsocket.c
index b5cdc60080..0c13620258 100644
--- a/ext/socket/ipsocket.c
+++ b/ext/socket/ipsocket.c
@@ -14,8 +14,8 @@ struct inetsock_arg
 {
     VALUE sock;
     struct {
-	VALUE host, serv;
-	struct rb_addrinfo *res;
+        VALUE host, serv;
+        struct rb_addrinfo *res;
     } remote, local;
     int type;
     int fd;
@@ -28,15 +28,15 @@ inetsock_cleanup(VALUE v)
 {
     struct inetsock_arg *arg = (void *)v;
     if (arg->remote.res) {
-	rb_freeaddrinfo(arg->remote.res);
-	arg->remote.res = 0;
+        rb_freeaddrinfo(arg->remote.res);
+        arg->remote.res = 0;
     }
     if (arg->local.res) {
-	rb_freeaddrinfo(arg->local.res);
-	arg->local.res = 0;
+        rb_freeaddrinfo(arg->local.res);
+        arg->local.res = 0;
     }
     if (arg->fd >= 0) {
-	close(arg->fd);
+        close(arg->fd);
     }
     return Qnil;
 }
@@ -61,8 +61,8 @@ init_inetsock_internal(VALUE v)
     }
 
     arg->remote.res = rsock_addrinfo(arg->remote.host, arg->remote.serv,
-				     family, SOCK_STREAM,
-				     (type == INET_SERVER) ? AI_PASSIVE : 0);
+                                     family, SOCK_STREAM,
+                                     (type == INET_SERVER) ? AI_PASSIVE : 0);
 
 
     /*
@@ -70,15 +70,15 @@ init_inetsock_internal(VALUE v)
      */
 
     if (type != INET_SERVER && (!NIL_P(arg->local.host) || !NIL_P(arg->local.serv))) {
-	arg->local.res = rsock_addrinfo(arg->local.host, arg->local.serv,
-					family, SOCK_STREAM, 0);
+        arg->local.res = rsock_addrinfo(arg->local.host, arg->local.serv,
+                                        family, SOCK_STREAM, 0);
     }
 
     arg->fd = fd = -1;
     for (res = arg->remote.res->ai; res; res = res->ai_next) {
 #if !defined(INET6) && defined(AF_INET6)
-	if (res->ai_family == AF_INET6)
-	    continue;
+        if (res->ai_family == AF_INET6)
+            continue;
 #endif
         lres = NULL;
         if (arg->local.res) {
@@ -94,73 +94,73 @@ init_inetsock_internal(VALUE v)
                 lres = arg->local.res->ai;
             }
         }
-	status = rsock_socket(res->ai_family,res->ai_socktype,res->ai_protocol);
-	syscall = "socket(2)";
-	fd = status;
-	if (fd < 0) {
-	    error = errno;
-	    continue;
-	}
-	arg->fd = fd;
-	if (type == INET_SERVER) {
+        status = rsock_socket(res->ai_family,res->ai_socktype,res->ai_protocol);
+        syscall = "socket(2)";
+        fd = status;
+        if (fd < 0) {
+            error = errno;
+            continue;
+        }
+        arg->fd = fd;
+        if (type == INET_SERVER) {
 #if !defined(_WIN32) && !defined(__CYGWIN__)
-	    status = 1;
-	    setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
-		       (char*)&status, (socklen_t)sizeof(status));
+            status = 1;
+            setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
+                       (char*)&status, (socklen_t)sizeof(status));
 #endif
-	    status = bind(fd, res->ai_addr, res->ai_addrlen);
-	    syscall = "bind(2)";
-	}
-	else {
-	    if (lres) {
+            status = bind(fd, res->ai_addr, res->ai_addrlen);
+            syscall = "bind(2)";
+        }
+        else {
+            if (lres) {
 #if !defined(_WIN32) && !defined(__CYGWIN__)
                 status = 1;
                 setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
                            (char*)&status, (socklen_t)sizeof(status));
 #endif
-		status = bind(fd, lres->ai_addr, lres->ai_addrlen);
-		local = status;
-		syscall = "bind(2)";
-	    }
-
-	    if (status >= 0) {
-		status = rsock_connect(fd, res->ai_addr, res->ai_addrlen,
-				       (type == INET_SOCKS), tv);
-		syscall = "connect(2)";
-	    }
-	}
-
-	if (status < 0) {
-	    error = errno;
-	    close(fd);
-	    arg->fd = fd = -1;
-	    continue;
-	} else
-	    break;
+                status = bind(fd, lres->ai_addr, lres->ai_addrlen);
+                local = status;
+                syscall = "bind(2)";
+            }
+
+            if (status >= 0) {
+                status = rsock_connect(fd, res->ai_addr, res->ai_addrlen,
+                                       (type == INET_SOCKS), tv);
+                syscall = "connect(2)";
+            }
+        }
+
+        if (status < 0) {
+            error = errno;
+            close(fd);
+            arg->fd = fd = -1;
+            continue;
+        } else
+            break;
     }
     if (status < 0) {
-	VALUE host, port;
-
-	if (local < 0) {
-	    host = arg->local.host;
-	    port = arg->local.serv;
-	} else {
-	    host = arg->remote.host;
-	    port = arg->remote.serv;
-	}
+        VALUE host, port;
+
+        if (local < 0) {
+            host = arg->local.host;
+            port = arg->local.serv;
+        } else {
+            host = arg->remote.host;
+            port = arg->remote.serv;
+        }
 
-	rsock_syserr_fail_host_port(error, syscall, host, port);
+        rsock_syserr_fail_host_port(error, syscall, host, port);
     }
 
     arg->fd = -1;
 
     if (type == INET_SERVER) {
-	status = listen(fd, SOMAXCONN);
-	if (status < 0) {
-	    error = errno;
-	    close(fd);
-	    rb_syserr_fail(error, "listen(2)");
-	}
+        status = listen(fd, SOMAXCONN);
+        if (status < 0) {
+            error = errno;
+            close(fd);
+            rb_syserr_fail(error, "listen(2)");
+        }
     }
 
     /* create new instance */
@@ -169,8 +169,8 @@ init_inetsock_internal(VALUE v)
 
 VALUE
 rsock_init_inetsock(VALUE sock, VALUE remote_host, VALUE remote_serv,
-	            VALUE local_host, VALUE local_serv, int type,
-		    VALUE resolv_timeout, VALUE connect_timeout)
+                    VALUE local_host, VALUE local_serv, int type,
+                    VALUE resolv_timeout, VALUE connect_timeout)
 {
     struct inetsock_arg arg;
     arg.sock = sock;
@@ -185,7 +185,7 @@ rsock_init_inetsock(VALUE sock, VALUE remote_host, VALUE remote_serv,
     arg.resolv_timeout = resolv_timeout;
     arg.connect_timeout = connect_timeout;
     return rb_ensure(init_inetsock_internal, (VALUE)&arg,
-		     inetsock_cleanup, (VALUE)&arg);
+                     inetsock_cleanup, (VALUE)&arg);
 }
 
 static ID id_numeric, id_hostname;
@@ -201,11 +201,11 @@ rsock_revlookup_flag(VALUE revlookup, int *norevlookup)
       case Qfalse: return_norevlookup(1);
       case Qnil: break;
       default:
-	Check_Type(revlookup, T_SYMBOL);
-	id = SYM2ID(revlookup);
-	if (id == id_numeric) return_norevlookup(1);
-	if (id == id_hostname) return_norevlookup(0);
-	rb_raise(rb_eArgError, "invalid reverse_lookup flag: :%s", rb_id2name(id));
+        Check_Type(revlookup, T_SYMBOL);
+        id = SYM2ID(revlookup);
+        if (id == id_numeric) return_norevlookup(1);
+        if (id == id_hostname) return_norevlookup(0);
+        rb_raise(rb_eArgError, "invalid reverse_lookup flag: :%s", rb_id2name(id));
     }
     return 0;
 #undef return_norevlookup
@@ -226,24 +226,24 @@ ip_inspect(VALUE sock)
     socklen_t len = (socklen_t)sizeof addr;
     ID id;
     if (fptr && fptr->fd >= 0 &&
-	getsockname(fptr->fd, &addr.addr, &len) >= 0 &&
-	(id = rsock_intern_family(addr.addr.sa_family)) != 0) {
-	VALUE family = rb_id2str(id);
-	char hbuf[1024], pbuf[1024];
-	long slen = RSTRING_LEN(str);
-	const char last = (slen > 1 && RSTRING_PTR(str)[slen - 1] == '>') ?
-	    (--slen, '>') : 0;
-	str = rb_str_subseq(str, 0, slen);
-	rb_str_cat_cstr(str, ", ");
-	rb_str_append(str, family);
-	if (!rb_getnameinfo(&addr.addr, len, hbuf, sizeof(hbuf),
-			    pbuf, sizeof(pbuf), NI_NUMERICHOST | NI_NUMERICSERV)) {
-	    rb_str_cat_cstr(str, ", ");
-	    rb_str_cat_cstr(str, hbuf);
-	    rb_str_cat_cstr(str, ", ");
-	    rb_str_cat_cstr(str, pbuf);
-	}
-	if (last) rb_str_cat(str, &last, 1);
+        getsockname(fptr->fd, &addr.addr, &len) >= 0 &&
+        (id = rsock_intern_family(addr.addr.sa_family)) != 0) {
+        VALUE family = rb_id2str(id);
+        char hbuf[1024], pbuf[1024];
+        long slen = RSTRING_LEN(str);
+        const char last = (slen > 1 && RSTRING_PTR(str)[slen - 1] == '>') ?
+            (--slen, '>') : 0;
+        str = rb_str_subseq(str, 0, slen);
+        rb_str_cat_cstr(str, ", ");
+        rb_str_append(str, family);
+        if (!rb_getnameinfo(&addr.addr, len, hbuf, sizeof(hbuf),
+                            pbuf, sizeof(pbuf), NI_NUMERICHOST | NI_NUMERICSERV)) {
+            rb_str_cat_cstr(str, ", ");
+            rb_str_cat_cstr(str, hbuf);
+            rb_str_cat_cstr(str, ", ");
+            rb_str_cat_cstr(str, pbuf);
+        }
+        if (last) rb_str_cat(str, &last, 1);
     }
     return str;
 }
@@ -282,9 +282,9 @@ ip_addr(int argc, VALUE *argv, VALUE sock)
     GetOpenFile(sock, fptr);
 
     if (argc < 1 || !rsock_revlookup_flag(argv[0], &norevlookup))
-	norevlookup = fptr->mode & FMODE_NOREVLOOKUP;
+        norevlookup = fptr->mode & FMODE_NOREVLOOKUP;
     if (getsockname(fptr->fd, &addr.addr, &len) < 0)
-	rb_sys_fail("getsockname(2)");
+        rb_sys_fail("getsockname(2)");
     return rsock_ipaddr(&addr.addr, len, norevlookup);
 }
 
@@ -323,9 +323,9 @@ ip_peeraddr(int argc, VALUE *argv, VALUE sock)
     GetOpenFile(sock, fptr);
 
     if (argc < 1 || !rsock_revlookup_flag(argv[0], &norevlookup))
-	norevlookup = fptr->mode & FMODE_NOREVLOOKUP;
+        norevlookup = fptr->mode & FMODE_NOREVLOOKUP;
     if (getpeername(fptr->fd, &addr.addr, &len) < 0)
-	rb_sys_fail("getpeername(2)");
+        rb_sys_fail("getpeername(2)");
     return rsock_ipaddr(&addr.addr, len, norevlookup);
 }
 
diff --git a/ext/socket/lib/socket.rb b/ext/socket/lib/socket.rb
index d756a32a5a..eecdc7d4b8 100644
--- a/ext/socket/lib/socket.rb
+++ b/ext/socket/lib/socket.rb
@@ -1,7 +1,11 @@
 # frozen_string_literal: true
 
 require 'socket.so'
-require 'io/wait'
+
+unless IO.method_defined?(:wait_writable, false)
+  # It's only required on older Rubies < v3.2:
+  require 'io/wait'
+end
 
 class Addrinfo
   # creates an Addrinfo object from the arguments.
@@ -197,7 +201,7 @@ class Addrinfo
     sock = Socket.new(self.pfamily, self.socktype, self.protocol)
     begin
       sock.ipv6only! if self.ipv6?
-      sock.setsockopt(:SOCKET, :REUSEADDR, 1)
+      sock.setsockopt(:SOCKET, :REUSEADDR, 1) unless self.pfamily == Socket::PF_UNIX
       sock.bind(self)
       sock.listen(backlog)
     rescue Exception
@@ -606,7 +610,6 @@ class Socket < BasicSocket
   # _opts_ may have following options:
   #
   # [:connect_timeout] specify the timeout in seconds.
-  # [:resolv_timeout] specify the name resolution timeout in seconds.
   #
   # If a block is given, the block is called with the socket.
   # The value of the block is returned.
diff --git a/ext/socket/mkconstants.rb b/ext/socket/mkconstants.rb
index 577958a358..5e6c0668f6 100644
--- a/ext/socket/mkconstants.rb
+++ b/ext/socket/mkconstants.rb
@@ -626,6 +626,7 @@ SO_SNDTIMEO	nil	Send timeout
 SO_ACCEPTCONN	nil	Socket has had listen() called on it
 SO_USELOOPBACK	nil	Bypass hardware when possible
 SO_ACCEPTFILTER	nil	There is an accept filter
+SO_USER_COOKIE	nil	Setting an identifier for ipfw purpose mainly
 SO_DONTTRUNC	nil	Retain unread data
 SO_WANTMORE	nil	Give a hint when more data is ready
 SO_WANTOOBFLAG	nil	OOB data is wanted in MSG_FLAG on receive
@@ -661,6 +662,10 @@ SO_SELECT_ERR_QUEUE     nil     Make select() detect socket error queue with err
 SO_BUSY_POLL    nil     Set the threshold in microseconds for low latency polling (Linux 3.11)
 SO_MAX_PACING_RATE      nil     Cap the rate computed by transport layer. [bytes per second] (Linux 3.13)
 SO_BPF_EXTENSIONS       nil     Query supported BPF extensions (Linux 3.14)
+SO_SETFIB       nil     Set the associated routing table for the socket (FreeBSD)
+SO_RTABLE               nil     Set the routing table for this socket (OpenBSD)
+SO_INCOMING_CPU         nil     Receive the cpu attached to the socket (Linux 3.19)
+SO_INCOMING_NAPI_ID     nil     Receive the napi ID attached to a RX queue (Linux 4.12)
 
 SOPRI_INTERACTIVE	nil	Interactive socket priority
 SOPRI_NORMAL	nil	Normal socket priority
@@ -670,9 +675,11 @@ IPX_TYPE
 
 TCP_NODELAY	nil	Don't delay sending to coalesce packets
 TCP_MAXSEG	nil	Set maximum segment size
+TCP_CONNECTION_INFO     nil     Retrieve information about this socket (macOS)
 TCP_CORK	nil	Don't send partial frames (Linux 2.2, glibc 2.2)
 TCP_DEFER_ACCEPT	nil	Don't notify a listening socket until data is ready (Linux 2.4, glibc 2.2)
 TCP_INFO	nil	Retrieve information about this socket (Linux 2.4, glibc 2.2)
+TCP_KEEPALIVE	nil	Idle time before keepalive probes are sent (macOS)
 TCP_KEEPCNT	nil	Maximum number of keepalive probes allowed before dropping a connection (Linux 2.4, glibc 2.2)
 TCP_KEEPIDLE	nil	Idle time before keepalive probes are sent (Linux 2.4, glibc 2.2)
 TCP_KEEPINTVL	nil	Time between keepalive probes (Linux 2.4, glibc 2.2)
diff --git a/ext/socket/option.c b/ext/socket/option.c
index 4b33b3f1d3..0d818d0c70 100644
--- a/ext/socket/option.c
+++ b/ext/socket/option.c
@@ -31,7 +31,7 @@ VALUE rb_cSockOpt;
     ((len) == (size) ? \
      (void)0 : \
      rb_raise(rb_eTypeError, "size differ.  expected as "#size"=%d but %ld", \
-	      (int)size, (long)(len)))
+              (int)size, (long)(len)))
 
 static VALUE
 sockopt_pack_byte(VALUE value)
@@ -309,7 +309,7 @@ sockopt_bool(VALUE self)
     StringValue(data);
     len = RSTRING_LEN(data);
     if (len == 1) {
-	return *RSTRING_PTR(data) == 0 ? Qfalse : Qtrue;
+        return *RSTRING_PTR(data) == 0 ? Qfalse : Qtrue;
     }
     check_size(len, sizeof(int));
     memcpy((char*)&i, RSTRING_PTR(data), len);
@@ -420,7 +420,7 @@ sockopt_ipv4_multicast_loop(VALUE self)
 
 #if defined(IPPROTO_IP) && defined(IP_MULTICAST_LOOP)
     if (family == AF_INET && level == IPPROTO_IP && optname == IP_MULTICAST_LOOP) {
-	return XCAT(sockopt_,TYPE_IP_MULTICAST_LOOP)(self);
+        return XCAT(sockopt_,TYPE_IP_MULTICAST_LOOP)(self);
     }
 #endif
     rb_raise(rb_eTypeError, "ipv4_multicast_loop socket option expected");
@@ -471,7 +471,7 @@ sockopt_ipv4_multicast_ttl(VALUE self)
 
 #if defined(IPPROTO_IP) && defined(IP_MULTICAST_TTL)
     if (family == AF_INET && level == IPPROTO_IP && optname == IP_MULTICAST_TTL) {
-	return XCAT(sockopt_,TYPE_IP_MULTICAST_TTL)(self);
+        return XCAT(sockopt_,TYPE_IP_MULTICAST_TTL)(self);
     }
 #endif
     rb_raise(rb_eTypeError, "ipv4_multicast_ttl socket option expected");
@@ -657,8 +657,8 @@ inet_ntop(int af, const void *addr, char *numaddr, size_t numaddr_len)
 #else
     unsigned long x = ntohl(*(unsigned long*)addr);
     snprintf(numaddr, numaddr_len, "%d.%d.%d.%d",
-	     (int) (x>>24) & 0xff, (int) (x>>16) & 0xff,
-	     (int) (x>> 8) & 0xff, (int) (x>> 0) & 0xff);
+             (int) (x>>24) & 0xff, (int) (x>>16) & 0xff,
+             (int) (x>> 8) & 0xff, (int) (x>> 0) & 0xff);
 #endif
     return numaddr;
 }
@@ -670,10 +670,10 @@ rb_if_indextoname(const char *succ_prefix, const char *fail_prefix, unsigned int
 {
 #if defined(HAVE_IF_INDEXTONAME)
     char ifbuf[IFNAMSIZ];
-    if (if_indextoname(ifindex, ifbuf) == NULL)
-        return snprintf(buf, len, "%s%u", fail_prefix, ifindex);
-    else
+    if (if_indextoname(ifindex, ifbuf))
         return snprintf(buf, len, "%s%s", succ_prefix, ifbuf);
+    else
+        return snprintf(buf, len, "%s%u", fail_prefix, ifindex);
 #else
 #   ifndef IFNAMSIZ
 #       define IFNAMSIZ (sizeof(unsigned int)*3+1)
@@ -1059,16 +1059,16 @@ inspect_tcp_info(int level, int optname, VALUE data, VALUE ret)
         rb_str_catf(ret, " fackets=%u", s.tcpi_fackets);
 #endif
 #ifdef HAVE_STRUCT_TCP_INFO_TCPI_LAST_DATA_SENT
-	inspect_tcpi_last_data_sent(ret, s.tcpi_last_data_sent);
+        inspect_tcpi_last_data_sent(ret, s.tcpi_last_data_sent);
 #endif
 #ifdef HAVE_STRUCT_TCP_INFO_TCPI_LAST_ACK_SENT
-	inspect_tcpi_last_ack_sent(ret, s.tcpi_last_ack_sent);
+        inspect_tcpi_last_ack_sent(ret, s.tcpi_last_ack_sent);
 #endif
 #ifdef HAVE_STRUCT_TCP_INFO_TCPI_LAST_DATA_RECV
-	inspect_tcpi_last_data_recv(ret, s.tcpi_last_data_recv);
+        inspect_tcpi_last_data_recv(ret, s.tcpi_last_data_recv);
 #endif
 #ifdef HAVE_STRUCT_TCP_INFO_TCPI_LAST_ACK_RECV
-	inspect_tcpi_last_ack_recv(ret, s.tcpi_last_ack_recv);
+        inspect_tcpi_last_ack_recv(ret, s.tcpi_last_ack_recv);
 #endif
 #ifdef HAVE_STRUCT_TCP_INFO_TCPI_PMTU
         rb_str_catf(ret, " pmtu=%u", s.tcpi_pmtu);
@@ -1077,10 +1077,10 @@ inspect_tcp_info(int level, int optname, VALUE data, VALUE ret)
         rb_str_catf(ret, " rcv_ssthresh=%u", s.tcpi_rcv_ssthresh);
 #endif
 #ifdef HAVE_STRUCT_TCP_INFO_TCPI_RTT
-	inspect_tcpi_rtt(ret, s.tcpi_rtt);
+        inspect_tcpi_rtt(ret, s.tcpi_rtt);
 #endif
 #ifdef HAVE_STRUCT_TCP_INFO_TCPI_RTTVAR
-	inspect_tcpi_rttvar(ret, s.tcpi_rttvar);
+        inspect_tcpi_rttvar(ret, s.tcpi_rttvar);
 #endif
 #ifdef HAVE_STRUCT_TCP_INFO_TCPI_SND_SSTHRESH
         rb_str_catf(ret, " snd_ssthresh=%u", s.tcpi_snd_ssthresh);
@@ -1150,7 +1150,7 @@ inspect_peercred(int level, int optname, VALUE data, VALUE ret)
         RUBY_SOCK_PEERCRED cred;
         memcpy(&cred, RSTRING_PTR(data), sizeof(RUBY_SOCK_PEERCRED));
         rb_str_catf(ret, " pid=%u euid=%u egid=%u",
-		    (unsigned)cred.pid, (unsigned)cred.uid, (unsigned)cred.gid);
+                    (unsigned)cred.pid, (unsigned)cred.uid, (unsigned)cred.gid);
         rb_str_cat2(ret, " (ucred)");
         return 1;
     }
@@ -1171,14 +1171,14 @@ inspect_local_peercred(int level, int optname, VALUE data, VALUE ret)
             return 0;
         rb_str_catf(ret, " version=%u", cred.cr_version);
         rb_str_catf(ret, " euid=%u", cred.cr_uid);
-	if (cred.cr_ngroups) {
-	    int i;
-	    const char *sep = " groups=";
-	    for (i = 0; i < cred.cr_ngroups; i++) {
-		rb_str_catf(ret, "%s%u", sep, cred.cr_groups[i]);
-		sep = ",";
-	    }
-	}
+        if (cred.cr_ngroups) {
+            int i;
+            const char *sep = " groups=";
+            for (i = 0; i < cred.cr_ngroups; i++) {
+                rb_str_catf(ret, "%s%u", sep, cred.cr_groups[i]);
+                sep = ",";
+            }
+        }
         rb_str_cat2(ret, " (xucred)");
         return 1;
     }
@@ -1216,42 +1216,42 @@ sockopt_inspect(VALUE self)
 
     family_id = rsock_intern_family_noprefix(family);
     if (family_id)
-	rb_str_catf(ret, " %s", rb_id2name(family_id));
+        rb_str_catf(ret, " %s", rb_id2name(family_id));
     else
         rb_str_catf(ret, " family:%d", family);
 
     if (level == SOL_SOCKET) {
         rb_str_cat2(ret, " SOCKET");
 
-	optname_id = rsock_intern_so_optname(optname);
-	if (optname_id)
-	    rb_str_catf(ret, " %s", rb_id2name(optname_id));
-	else
-	    rb_str_catf(ret, " optname:%d", optname);
+        optname_id = rsock_intern_so_optname(optname);
+        if (optname_id)
+            rb_str_catf(ret, " %s", rb_id2name(optname_id));
+        else
+            rb_str_catf(ret, " optname:%d", optname);
     }
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
     else if (family == AF_UNIX) {
-	rb_str_catf(ret, " level:%d", level);
+        rb_str_catf(ret, " level:%d", level);
 
-	optname_id = rsock_intern_local_optname(optname);
-	if (optname_id)
-	    rb_str_catf(ret, " %s", rb_id2name(optname_id));
-	else
-	    rb_str_catf(ret, " optname:%d", optname);
+        optname_id = rsock_intern_local_optname(optname);
+        if (optname_id)
+            rb_str_catf(ret, " %s", rb_id2name(optname_id));
+        else
+            rb_str_catf(ret, " optname:%d", optname);
     }
 #endif
     else if (IS_IP_FAMILY(family)) {
-	level_id = rsock_intern_iplevel(level);
-	if (level_id)
-	    rb_str_catf(ret, " %s", rb_id2name(level_id));
-	else
-	    rb_str_catf(ret, " level:%d", level);
-
-	v = optname_to_sym(level, optname);
-	if (SYMBOL_P(v))
-	    rb_str_catf(ret, " %"PRIsVALUE, rb_sym2str(v));
-	else
-	    rb_str_catf(ret, " optname:%d", optname);
+        level_id = rsock_intern_iplevel(level);
+        if (level_id)
+            rb_str_catf(ret, " %s", rb_id2name(level_id));
+        else
+            rb_str_catf(ret, " level:%d", level);
+
+        v = optname_to_sym(level, optname);
+        if (SYMBOL_P(v))
+            rb_str_catf(ret, " %"PRIsVALUE, rb_sym2str(v));
+        else
+            rb_str_catf(ret, " optname:%d", optname);
     }
     else {
         rb_str_catf(ret, " level:%d", level);
@@ -1393,7 +1393,7 @@ sockopt_inspect(VALUE self)
         }
         break;
 
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
       case AF_UNIX:
         switch (level) {
           case 0:
diff --git a/ext/socket/raddrinfo.c b/ext/socket/raddrinfo.c
index 8772572d2e..45b4cad38f 100644
--- a/ext/socket/raddrinfo.c
+++ b/ext/socket/raddrinfo.c
@@ -24,28 +24,28 @@ static const int lookup_order_table[] = {
 
 static int
 ruby_getaddrinfo(const char *nodename, const char *servname,
-		 const struct addrinfo *hints, struct addrinfo **res)
+                 const struct addrinfo *hints, struct addrinfo **res)
 {
     struct addrinfo tmp_hints;
     int i, af, error;
 
     if (hints->ai_family != PF_UNSPEC) {
-	return getaddrinfo(nodename, servname, hints, res);
+        return getaddrinfo(nodename, servname, hints, res);
     }
 
     for (i = 0; i < LOOKUP_ORDERS; i++) {
-	af = lookup_order_table[i];
-	MEMCPY(&tmp_hints, hints, struct addrinfo, 1);
-	tmp_hints.ai_family = af;
-	error = getaddrinfo(nodename, servname, &tmp_hints, res);
-	if (error) {
-	    if (tmp_hints.ai_family == PF_UNSPEC) {
-		break;
-	    }
-	}
-	else {
-	    break;
-	}
+        af = lookup_order_table[i];
+        MEMCPY(&tmp_hints, hints, struct addrinfo, 1);
+        tmp_hints.ai_family = af;
+        error = getaddrinfo(nodename, servname, &tmp_hints, res);
+        if (error) {
+            if (tmp_hints.ai_family == PF_UNSPEC) {
+                break;
+            }
+        }
+        else {
+            break;
+        }
     }
 
     return error;
@@ -56,17 +56,17 @@ ruby_getaddrinfo(const char *nodename, const char *servname,
 #if defined(_AIX)
 static int
 ruby_getaddrinfo__aix(const char *nodename, const char *servname,
-		      const struct addrinfo *hints, struct addrinfo **res)
+                      const struct addrinfo *hints, struct addrinfo **res)
 {
     int error = getaddrinfo(nodename, servname, hints, res);
     struct addrinfo *r;
     if (error)
-	return error;
+        return error;
     for (r = *res; r != NULL; r = r->ai_next) {
-	if (r->ai_addr->sa_family == 0)
-	    r->ai_addr->sa_family = r->ai_family;
-	if (r->ai_addr->sa_len == 0)
-	    r->ai_addr->sa_len = r->ai_addrlen;
+        if (r->ai_addr->sa_family == 0)
+            r->ai_addr->sa_family = r->ai_family;
+        if (r->ai_addr->sa_len == 0)
+            r->ai_addr->sa_len = r->ai_addrlen;
     }
     return 0;
 }
@@ -74,21 +74,21 @@ ruby_getaddrinfo__aix(const char *nodename, const char *servname,
 #define getaddrinfo(node,serv,hints,res) ruby_getaddrinfo__aix((node),(serv),(hints),(res))
 static int
 ruby_getnameinfo__aix(const struct sockaddr *sa, size_t salen,
-		      char *host, size_t hostlen,
-		      char *serv, size_t servlen, int flags)
+                      char *host, size_t hostlen,
+                      char *serv, size_t servlen, int flags)
 {
     struct sockaddr_in6 *sa6;
     u_int32_t *a6;
 
     if (sa->sa_family == AF_INET6) {
-	sa6 = (struct sockaddr_in6 *)sa;
-	a6 = sa6->sin6_addr.u6_addr.u6_addr32;
+        sa6 = (struct sockaddr_in6 *)sa;
+        a6 = sa6->sin6_addr.u6_addr.u6_addr32;
 
-	if (a6[0] == 0 && a6[1] == 0 && a6[2] == 0 && a6[3] == 0) {
-	    strncpy(host, "::", hostlen);
-	    snprintf(serv, servlen, "%d", sa6->sin6_port);
-	    return 0;
-	}
+        if (a6[0] == 0 && a6[1] == 0 && a6[2] == 0 && a6[3] == 0) {
+            strncpy(host, "::", hostlen);
+            snprintf(serv, servlen, "%d", sa6->sin6_port);
+            return 0;
+        }
     }
     return getnameinfo(sa, salen, host, hostlen, serv, servlen, flags);
 }
@@ -102,7 +102,7 @@ static int str_is_number(const char *);
 #if defined(__APPLE__)
 static int
 ruby_getaddrinfo__darwin(const char *nodename, const char *servname,
-			 const struct addrinfo *hints, struct addrinfo **res)
+                         const struct addrinfo *hints, struct addrinfo **res)
 {
     /* fix [ruby-core:29427] */
     const char *tmp_servname;
@@ -112,12 +112,12 @@ ruby_getaddrinfo__darwin(const char *nodename, const char *servname,
     tmp_servname = servname;
     MEMCPY(&tmp_hints, hints, struct addrinfo, 1);
     if (nodename && servname) {
-	if (str_is_number(tmp_servname) && atoi(servname) == 0) {
-	    tmp_servname = NULL;
+        if (str_is_number(tmp_servname) && atoi(servname) == 0) {
+            tmp_servname = NULL;
 #ifdef AI_NUMERICSERV
-	    if (tmp_hints.ai_flags) tmp_hints.ai_flags &= ~AI_NUMERICSERV;
+            if (tmp_hints.ai_flags) tmp_hints.ai_flags &= ~AI_NUMERICSERV;
 #endif
-	}
+        }
     }
 
     error = getaddrinfo(nodename, tmp_servname, &tmp_hints, res);
@@ -193,7 +193,7 @@ nogvl_getaddrinfo(void *arg)
      * it cause getaddrinfo to return EAI_SYSTEM/ENOENT. [ruby-list:49420]
      */
     if (ret == EAI_SYSTEM && errno == ENOENT)
-	ret = EAI_NONAME;
+        ret = EAI_NONAME;
 #endif
     return (void *)(VALUE)ret;
 }
@@ -212,15 +212,15 @@ numeric_getaddrinfo(const char *node, const char *service,
     int port;
 
     if (node && parse_numeric_port(service, &port)) {
-	static const struct {
-	    int socktype;
-	    int protocol;
-	} list[] = {
-	    { SOCK_STREAM, IPPROTO_TCP },
-	    { SOCK_DGRAM, IPPROTO_UDP },
-	    { SOCK_RAW, 0 }
-	};
-	struct addrinfo *ai = NULL;
+        static const struct {
+            int socktype;
+            int protocol;
+        } list[] = {
+            { SOCK_STREAM, IPPROTO_TCP },
+            { SOCK_DGRAM, IPPROTO_UDP },
+            { SOCK_RAW, 0 }
+        };
+        struct addrinfo *ai = NULL;
         int hint_family = hints ? hints->ai_family : PF_UNSPEC;
         int hint_socktype = hints ? hints->ai_socktype : 0;
         int hint_protocol = hints ? hints->ai_protocol : 0;
@@ -287,8 +287,9 @@ numeric_getaddrinfo(const char *node, const char *service,
 void
 rb_freeaddrinfo(struct rb_addrinfo *ai)
 {
-    if (!ai->allocated_by_malloc)
-        freeaddrinfo(ai->ai);
+    if (!ai->allocated_by_malloc) {
+        if (ai->ai) freeaddrinfo(ai->ai);
+    }
     else {
         struct addrinfo *ai1, *ai2;
         ai1 = ai->ai;
@@ -319,9 +320,9 @@ nogvl_getnameinfo(void *arg)
 {
     struct getnameinfo_arg *ptr = arg;
     return (void *)(VALUE)getnameinfo(ptr->sa, ptr->salen,
-				      ptr->host, (socklen_t)ptr->hostlen,
-				      ptr->serv, (socklen_t)ptr->servlen,
-				      ptr->flags);
+                                      ptr->host, (socklen_t)ptr->hostlen,
+                                      ptr->serv, (socklen_t)ptr->servlen,
+                                      ptr->flags);
 }
 #endif
 
@@ -587,7 +588,7 @@ rsock_fd_family(int fd)
 
     if (fd < 0 || getsockname(fd, &sa, &sa_len) != 0 ||
         (size_t)sa_len < offsetof(struct sockaddr, sa_family) + sizeof(sa.sa_family)) {
-	return AF_UNSPEC;
+        return AF_UNSPEC;
     }
     return sa.sa_family;
 }
@@ -618,8 +619,7 @@ rsock_ipaddr(struct sockaddr *sockaddr, socklen_t sockaddrlen, int norevlookup)
         family = rb_str_dup(rb_id2str(id));
     }
     else {
-        sprintf(pbuf, "unknown:%d", sockaddr->sa_family);
-        family = rb_str_new2(pbuf);
+        family = rb_sprintf("unknown:%d", sockaddr->sa_family);
     }
 
     addr1 = Qnil;
@@ -645,7 +645,7 @@ rsock_ipaddr(struct sockaddr *sockaddr, socklen_t sockaddrlen, int norevlookup)
     return ary;
 }
 
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
 static long
 unixsocket_len(const struct sockaddr_un *su, socklen_t socklen)
 {
@@ -677,19 +677,19 @@ rsock_unix_sockaddr_len(VALUE path)
 {
 #ifdef __linux__
     if (RSTRING_LEN(path) == 0) {
-	/* autobind; see unix(7) for details. */
-	return (socklen_t) sizeof(sa_family_t);
+        /* autobind; see unix(7) for details. */
+        return (socklen_t) sizeof(sa_family_t);
     }
     else if (RSTRING_PTR(path)[0] == '\0') {
-	/* abstract namespace; see unix(7) for details. */
+        /* abstract namespace; see unix(7) for details. */
         if (SOCKLEN_MAX - offsetof(struct sockaddr_un, sun_path) < (size_t)RSTRING_LEN(path))
             rb_raise(rb_eArgError, "Linux abstract socket too long");
-	return (socklen_t) offsetof(struct sockaddr_un, sun_path) +
-	    RSTRING_SOCKLEN(path);
+        return (socklen_t) offsetof(struct sockaddr_un, sun_path) +
+            RSTRING_SOCKLEN(path);
     }
     else {
 #endif
-	return (socklen_t) sizeof(struct sockaddr_un);
+        return (socklen_t) sizeof(struct sockaddr_un);
 #ifdef __linux__
     }
 #endif
@@ -727,7 +727,7 @@ make_hostent_internal(VALUE v)
     rb_ary_push(ary, rb_str_new2(hostp));
 
     if (addr->ai_canonname && strlen(addr->ai_canonname) < NI_MAXHOST &&
-	(h = gethostbyname(addr->ai_canonname))) {
+        (h = gethostbyname(addr->ai_canonname))) {
         names = rb_ary_new();
         if (h->h_aliases != NULL) {
             for (pch = h->h_aliases; *pch; pch++) {
@@ -875,19 +875,19 @@ call_getaddrinfo(VALUE node, VALUE service,
     hints.ai_family = NIL_P(family) ? PF_UNSPEC : rsock_family_arg(family);
 
     if (!NIL_P(socktype)) {
-	hints.ai_socktype = rsock_socktype_arg(socktype);
+        hints.ai_socktype = rsock_socktype_arg(socktype);
     }
     if (!NIL_P(protocol)) {
-	hints.ai_protocol = NUM2INT(protocol);
+        hints.ai_protocol = NUM2INT(protocol);
     }
     if (!NIL_P(flags)) {
-	hints.ai_flags = NUM2INT(flags);
+        hints.ai_flags = NUM2INT(flags);
     }
 
     res = rsock_getaddrinfo(node, service, &hints, socktype_hack);
 
     if (res == NULL)
-	rb_raise(rb_eSocket, "host not found");
+        rb_raise(rb_eSocket, "host not found");
     return res;
 }
 
@@ -1018,7 +1018,7 @@ addrinfo_list_new(VALUE node, VALUE service, VALUE family, VALUE socktype, VALUE
 }
 
 
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
 static void
 init_unix_addrinfo(rb_addrinfo_t *rai, VALUE path, int socktype)
 {
@@ -1037,7 +1037,7 @@ init_unix_addrinfo(rb_addrinfo_t *rai, VALUE path, int socktype)
 
     len = rsock_unix_sockaddr_len(path);
     init_addrinfo(rai, (struct sockaddr *)&un, len,
-		  PF_UNIX, socktype, 0, Qnil, Qnil);
+                  PF_UNIX, socktype, 0, Qnil, Qnil);
 }
 
 static long
@@ -1119,7 +1119,7 @@ addrinfo_initialize(int argc, VALUE *argv, VALUE self)
         int af;
         StringValue(afamily);
         if (rsock_family_to_int(RSTRING_PTR(afamily), RSTRING_LEN(afamily), &af) == -1)
-	    rb_raise(rb_eSocket, "unknown address family: %s", StringValueCStr(afamily));
+            rb_raise(rb_eSocket, "unknown address family: %s", StringValueCStr(afamily));
         switch (af) {
           case AF_INET: /* ["AF_INET", 46102, "localhost.localdomain", "127.0.0.1"] */
 #ifdef INET6
@@ -1147,7 +1147,7 @@ addrinfo_initialize(int argc, VALUE *argv, VALUE self)
             break;
           }
 
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
           case AF_UNIX: /* ["AF_UNIX", "/tmp/sock"] */
           {
             VALUE path = rb_ary_entry(sockaddr_ary, 1);
@@ -1209,45 +1209,45 @@ rsock_inspect_sockaddr(struct sockaddr *sockaddr_arg, socklen_t socklen, VALUE r
     else {
         switch (sockaddr->addr.sa_family) {
           case AF_UNSPEC:
-	  {
-	    rb_str_cat2(ret, "UNSPEC");
+          {
+            rb_str_cat2(ret, "UNSPEC");
             break;
-	  }
+          }
 
           case AF_INET:
           {
             struct sockaddr_in *addr;
             int port;
-	    addr = &sockaddr->in;
-	    if ((socklen_t)(((char*)&addr->sin_addr)-(char*)addr+0+1) <= socklen)
-		rb_str_catf(ret, "%d", ((unsigned char*)&addr->sin_addr)[0]);
-	    else
-		rb_str_cat2(ret, "?");
-	    if ((socklen_t)(((char*)&addr->sin_addr)-(char*)addr+1+1) <= socklen)
-		rb_str_catf(ret, ".%d", ((unsigned char*)&addr->sin_addr)[1]);
-	    else
-		rb_str_cat2(ret, ".?");
-	    if ((socklen_t)(((char*)&addr->sin_addr)-(char*)addr+2+1) <= socklen)
-		rb_str_catf(ret, ".%d", ((unsigned char*)&addr->sin_addr)[2]);
-	    else
-		rb_str_cat2(ret, ".?");
-	    if ((socklen_t)(((char*)&addr->sin_addr)-(char*)addr+3+1) <= socklen)
-		rb_str_catf(ret, ".%d", ((unsigned char*)&addr->sin_addr)[3]);
-	    else
-		rb_str_cat2(ret, ".?");
-
-	    if ((socklen_t)(((char*)&addr->sin_port)-(char*)addr+(int)sizeof(addr->sin_port)) < socklen) {
-		port = ntohs(addr->sin_port);
-		if (port)
-		    rb_str_catf(ret, ":%d", port);
-	    }
-	    else {
-		rb_str_cat2(ret, ":?");
-	    }
-	    if ((socklen_t)sizeof(struct sockaddr_in) != socklen)
-		rb_str_catf(ret, " (%d bytes for %d bytes sockaddr_in)",
-		  (int)socklen,
-		  (int)sizeof(struct sockaddr_in));
+            addr = &sockaddr->in;
+            if ((socklen_t)(((char*)&addr->sin_addr)-(char*)addr+0+1) <= socklen)
+                rb_str_catf(ret, "%d", ((unsigned char*)&addr->sin_addr)[0]);
+            else
+                rb_str_cat2(ret, "?");
+            if ((socklen_t)(((char*)&addr->sin_addr)-(char*)addr+1+1) <= socklen)
+                rb_str_catf(ret, ".%d", ((unsigned char*)&addr->sin_addr)[1]);
+            else
+                rb_str_cat2(ret, ".?");
+            if ((socklen_t)(((char*)&addr->sin_addr)-(char*)addr+2+1) <= socklen)
+                rb_str_catf(ret, ".%d", ((unsigned char*)&addr->sin_addr)[2]);
+            else
+                rb_str_cat2(ret, ".?");
+            if ((socklen_t)(((char*)&addr->sin_addr)-(char*)addr+3+1) <= socklen)
+                rb_str_catf(ret, ".%d", ((unsigned char*)&addr->sin_addr)[3]);
+            else
+                rb_str_cat2(ret, ".?");
+
+            if ((socklen_t)(((char*)&addr->sin_port)-(char*)addr+(int)sizeof(addr->sin_port)) < socklen) {
+                port = ntohs(addr->sin_port);
+                if (port)
+                    rb_str_catf(ret, ":%d", port);
+            }
+            else {
+                rb_str_cat2(ret, ":?");
+            }
+            if ((socklen_t)sizeof(struct sockaddr_in) != socklen)
+                rb_str_catf(ret, " (%d bytes for %d bytes sockaddr_in)",
+                  (int)socklen,
+                  (int)sizeof(struct sockaddr_in));
             break;
           }
 
@@ -1287,7 +1287,7 @@ rsock_inspect_sockaddr(struct sockaddr *sockaddr_arg, socklen_t socklen, VALUE r
           }
 #endif
 
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
           case AF_UNIX:
           {
             struct sockaddr_un *addr = &sockaddr->un;
@@ -1398,20 +1398,20 @@ rsock_inspect_sockaddr(struct sockaddr *sockaddr_arg, socklen_t socklen, VALUE r
 #endif
 
 #if defined(AF_LINK) && defined(HAVE_TYPE_STRUCT_SOCKADDR_DL)
-	  /* AF_LINK is defined in 4.4BSD derivations since Net2.
-	     link_ntoa is also defined at Net2.
+          /* AF_LINK is defined in 4.4BSD derivations since Net2.
+             link_ntoa is also defined at Net2.
              However Debian GNU/kFreeBSD defines AF_LINK but
              don't have link_ntoa.  */
           case AF_LINK:
-	  {
-	    /*
-	     * Simple implementation using link_ntoa():
-	     * This doesn't work on Debian GNU/kFreeBSD 6.0.7 (squeeze).
+          {
+            /*
+             * Simple implementation using link_ntoa():
+             * This doesn't work on Debian GNU/kFreeBSD 6.0.7 (squeeze).
              * Also, the format is bit different.
-	     *
-	     * rb_str_catf(ret, "LINK %s", link_ntoa(&sockaddr->dl));
-	     * break;
-	     */
+             *
+             * rb_str_catf(ret, "LINK %s", link_ntoa(&sockaddr->dl));
+             * break;
+             */
             struct sockaddr_dl *addr = &sockaddr->dl;
             char *np = NULL, *ap = NULL, *endp;
             int nlen = 0, alen = 0;
@@ -1438,14 +1438,14 @@ rsock_inspect_sockaddr(struct sockaddr *sockaddr_arg, socklen_t socklen, VALUE r
                     alen = (int)(endp - ap);
             }
 
-	    CATSEP;
+            CATSEP;
             if (np)
                 rb_str_catf(ret, "%.*s", nlen, np);
             else
                 rb_str_cat2(ret, "?");
 
             if (ap && 0 < alen) {
-		CATSEP;
+                CATSEP;
                 for (i = 0; i < alen; i++)
                     rb_str_catf(ret, "%s%02x", i == 0 ? "" : ":", (unsigned char)ap[i]);
             }
@@ -1456,10 +1456,10 @@ rsock_inspect_sockaddr(struct sockaddr *sockaddr_arg, socklen_t socklen, VALUE r
                 /* longer length is possible behavior because struct sockaddr_dl has "minimum work area, can be larger" as the last field.
                  * cf. Net2:/usr/src/sys/net/if_dl.h. */
                 socklen < (socklen_t)(offsetof(struct sockaddr_dl, sdl_data) + addr->sdl_nlen + addr->sdl_alen + addr->sdl_slen)) {
-		CATSEP;
+                CATSEP;
                 rb_str_catf(ret, "(%d bytes for %d bytes sockaddr_dl)",
                     (int)socklen, (int)sizeof(struct sockaddr_dl));
-	    }
+            }
 
             rb_str_cat2(ret, "]");
 #undef CATSEP
@@ -1623,7 +1623,7 @@ addrinfo_mdump(VALUE self)
     afamily = rb_id2str(id);
 
     switch(afamily_int) {
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
       case AF_UNIX:
       {
         sockaddr = rb_str_new(rai->addr.un.sun_path, rai_unixsocket_len(rai));
@@ -1716,7 +1716,7 @@ addrinfo_mload(VALUE self, VALUE ary)
 
     v = rb_ary_entry(ary, 1);
     switch(afamily) {
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
       case AF_UNIX:
       {
         struct sockaddr_un uaddr;
@@ -2009,7 +2009,7 @@ addrinfo_ip_unpack(VALUE self)
     VALUE ret, portstr;
 
     if (!IS_IP_FAMILY(family))
-	rb_raise(rb_eSocket, "need IPv4 or IPv6 address");
+        rb_raise(rb_eSocket, "need IPv4 or IPv6 address");
 
     vflags = INT2NUM(NI_NUMERICHOST|NI_NUMERICSERV);
     ret = addrinfo_getnameinfo(1, &vflags, self);
@@ -2036,7 +2036,7 @@ addrinfo_ip_address(VALUE self)
     VALUE ret;
 
     if (!IS_IP_FAMILY(family))
-	rb_raise(rb_eSocket, "need IPv4 or IPv6 address");
+        rb_raise(rb_eSocket, "need IPv4 or IPv6 address");
 
     vflags = INT2NUM(NI_NUMERICHOST|NI_NUMERICSERV);
     ret = addrinfo_getnameinfo(1, &vflags, self);
@@ -2062,9 +2062,9 @@ addrinfo_ip_port(VALUE self)
     if (!IS_IP_FAMILY(family)) {
       bad_family:
 #ifdef AF_INET6
-	rb_raise(rb_eSocket, "need IPv4 or IPv6 address");
+        rb_raise(rb_eSocket, "need IPv4 or IPv6 address");
 #else
-	rb_raise(rb_eSocket, "need IPv4 address");
+        rb_raise(rb_eSocket, "need IPv4 address");
 #endif
     }
 
@@ -2084,7 +2084,7 @@ addrinfo_ip_port(VALUE self)
 #endif
 
       default:
-	goto bad_family;
+        goto bad_family;
     }
 
     return INT2NUM(port);
@@ -2192,7 +2192,7 @@ addrinfo_ipv6_multicast_p(VALUE self)
 }
 
 /*
- * Returns true for IPv6 link local address (ff80::/10).
+ * Returns true for IPv6 link local address (fe80::/10).
  * It returns false otherwise.
  */
 static VALUE
@@ -2204,7 +2204,7 @@ addrinfo_ipv6_linklocal_p(VALUE self)
 }
 
 /*
- * Returns true for IPv6 site local address (ffc0::/10).
+ * Returns true for IPv6 site local address (fec0::/10).
  * It returns false otherwise.
  */
 static VALUE
@@ -2344,7 +2344,7 @@ addrinfo_ipv6_to_ipv4(VALUE self)
 
 #endif
 
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
 /*
  * call-seq:
  *   addrinfo.unix_path => path
@@ -2362,7 +2362,7 @@ addrinfo_unix_path(VALUE self)
     long n;
 
     if (family != AF_UNIX)
-	rb_raise(rb_eSocket, "need AF_UNIX address");
+        rb_raise(rb_eSocket, "need AF_UNIX address");
 
     addr = &rai->addr.un;
 
@@ -2429,10 +2429,10 @@ addrinfo_s_getaddrinfo(int argc, VALUE *argv, VALUE self)
     VALUE node, service, family, socktype, protocol, flags, opts, timeout;
 
     rb_scan_args(argc, argv, "24:", &node, &service, &family, &socktype,
-		 &protocol, &flags, &opts);
+                 &protocol, &flags, &opts);
     rb_get_kwargs(opts, &id_timeout, 0, 1, &timeout);
     if (timeout == Qundef) {
-	timeout = Qnil;
+        timeout = Qnil;
     }
 
     return addrinfo_list_new(node, service, family, socktype, protocol, flags, timeout);
@@ -2492,7 +2492,7 @@ addrinfo_s_udp(VALUE self, VALUE host, VALUE port)
             INT2NUM(PF_UNSPEC), INT2NUM(SOCK_DGRAM), INT2NUM(IPPROTO_UDP), INT2FIX(0));
 }
 
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
 
 /*
  * call-seq:
@@ -2630,7 +2630,7 @@ rsock_init_addrinfo(void)
     rb_define_singleton_method(rb_cAddrinfo, "ip", addrinfo_s_ip, 1);
     rb_define_singleton_method(rb_cAddrinfo, "tcp", addrinfo_s_tcp, 2);
     rb_define_singleton_method(rb_cAddrinfo, "udp", addrinfo_s_udp, 2);
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
     rb_define_singleton_method(rb_cAddrinfo, "unix", addrinfo_s_unix, -1);
 #endif
 
@@ -2671,7 +2671,7 @@ rsock_init_addrinfo(void)
     rb_define_method(rb_cAddrinfo, "ipv6_to_ipv4", addrinfo_ipv6_to_ipv4, 0);
 #endif
 
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
     rb_define_method(rb_cAddrinfo, "unix_path", addrinfo_unix_path, 0);
 #endif
 
diff --git a/ext/socket/rubysocket.h b/ext/socket/rubysocket.h
index c0d40addca..5f803ba0da 100644
--- a/ext/socket/rubysocket.h
+++ b/ext/socket/rubysocket.h
@@ -33,6 +33,9 @@
 #endif
 
 #ifdef _WIN32
+#  include <winsock2.h>
+#  include <ws2tcpip.h>
+#  include <iphlpapi.h>
 #  if defined(_MSC_VER)
 #    undef HAVE_TYPE_STRUCT_SOCKADDR_DL
 #  endif
@@ -69,6 +72,11 @@
 #  include <sys/un.h>
 #endif
 
+#ifdef HAVE_AFUNIX_H
+// Windows doesn't have sys/un.h, but it does have afunix.h just to be special:
+#  include <afunix.h>
+#endif
+
 #if defined(HAVE_FCNTL)
 #  ifdef HAVE_SYS_SELECT_H
 #    include <sys/select.h>
@@ -268,7 +276,7 @@ extern VALUE rb_cIPSocket;
 extern VALUE rb_cTCPSocket;
 extern VALUE rb_cTCPServer;
 extern VALUE rb_cUDPSocket;
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
 extern VALUE rb_cUNIXSocket;
 extern VALUE rb_cUNIXServer;
 #endif
@@ -336,7 +344,7 @@ VALUE rsock_sockaddr_obj(struct sockaddr *addr, socklen_t len);
 
 int rsock_revlookup_flag(VALUE revlookup, int *norevlookup);
 
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
 VALUE rsock_unixpath_str(struct sockaddr_un *sockaddr, socklen_t len);
 VALUE rsock_unixaddr(struct sockaddr_un *sockaddr, socklen_t len);
 socklen_t rsock_unix_sockaddr_len(VALUE path);
@@ -368,23 +376,23 @@ enum sock_recv_type {
 };
 
 VALUE rsock_s_recvfrom_nonblock(VALUE sock, VALUE len, VALUE flg, VALUE str,
-			        VALUE ex, enum sock_recv_type from);
+                                VALUE ex, enum sock_recv_type from);
 VALUE rsock_s_recvfrom(VALUE sock, int argc, VALUE *argv, enum sock_recv_type from);
 
 int rsock_connect(int fd, const struct sockaddr *sockaddr, int len, int socks, struct timeval *timeout);
 
 VALUE rsock_s_accept(VALUE klass, VALUE io, struct sockaddr *sockaddr, socklen_t *len);
 VALUE rsock_s_accept_nonblock(VALUE klass, VALUE ex, rb_io_t *fptr,
-			      struct sockaddr *sockaddr, socklen_t *len);
+                              struct sockaddr *sockaddr, socklen_t *len);
 VALUE rsock_sock_listen(VALUE sock, VALUE log);
 
 VALUE rsock_sockopt_new(int family, int level, int optname, VALUE data);
 
 #if defined(HAVE_SENDMSG)
 VALUE rsock_bsock_sendmsg(VALUE sock, VALUE data, VALUE flags,
-			  VALUE dest_sockaddr, VALUE controls);
+                          VALUE dest_sockaddr, VALUE controls);
 VALUE rsock_bsock_sendmsg_nonblock(VALUE sock, VALUE data, VALUE flags,
-			     VALUE dest_sockaddr, VALUE controls, VALUE ex);
+                             VALUE dest_sockaddr, VALUE controls, VALUE ex);
 #else
 #define rsock_bsock_sendmsg rb_f_notimplement
 #define rsock_bsock_sendmsg_nonblock rb_f_notimplement
@@ -392,9 +400,9 @@ VALUE rsock_bsock_sendmsg_nonblock(VALUE sock, VALUE data, VALUE flags,
 
 #if defined(HAVE_RECVMSG)
 VALUE rsock_bsock_recvmsg(VALUE sock, VALUE dlen, VALUE clen, VALUE flags,
-			  VALUE scm_rights);
+                          VALUE scm_rights);
 VALUE rsock_bsock_recvmsg_nonblock(VALUE sock, VALUE dlen, VALUE clen,
-				   VALUE flags, VALUE scm_rights, VALUE ex);
+                                   VALUE flags, VALUE scm_rights, VALUE ex);
 ssize_t rsock_recvmsg(int socket, struct msghdr *message, int flags);
 #else
 #define rsock_bsock_recvmsg rb_f_notimplement
diff --git a/ext/socket/socket.c b/ext/socket/socket.c
index 4ba1c6cd61..eb74f7a936 100644
--- a/ext/socket/socket.c
+++ b/ext/socket/socket.c
@@ -26,7 +26,11 @@ rsock_syserr_fail_host_port(int err, const char *mesg, VALUE host, VALUE port)
     VALUE message;
 
     message = rb_sprintf("%s for %+"PRIsVALUE" port % "PRIsVALUE"",
-			 mesg, host, port);
+                         mesg, host, port);
+
+    if (err == ETIMEDOUT) {
+        rb_exc_raise(rb_exc_new3(rb_eIOTimeoutError, message));
+    }
 
     rb_syserr_fail_str(err, message);
 }
@@ -43,11 +47,11 @@ rsock_syserr_fail_path(int err, const char *mesg, VALUE path)
     VALUE message;
 
     if (RB_TYPE_P(path, T_STRING)) {
-	message = rb_sprintf("%s for % "PRIsVALUE"", mesg, path);
-	rb_syserr_fail_str(err, message);
+        message = rb_sprintf("%s for % "PRIsVALUE"", mesg, path);
+        rb_syserr_fail_str(err, message);
     }
     else {
-	rb_syserr_fail(err, mesg);
+        rb_syserr_fail(err, mesg);
     }
 }
 
@@ -96,12 +100,12 @@ rsock_syserr_fail_raddrinfo_or_sockaddr(int err, const char *mesg, VALUE addr, V
     if (NIL_P(rai)) {
         StringValue(addr);
 
-	rsock_syserr_fail_sockaddr(err, mesg,
+        rsock_syserr_fail_sockaddr(err, mesg,
             (struct sockaddr *)RSTRING_PTR(addr),
             (socklen_t)RSTRING_LEN(addr)); /* overflow should be checked already */
     }
     else
-	rsock_syserr_fail_raddrinfo(err, mesg, rai);
+        rsock_syserr_fail_raddrinfo(err, mesg, rai);
 }
 
 static void
@@ -256,7 +260,7 @@ rsock_sock_s_socketpair(int argc, VALUE *argv, VALUE klass)
     p = NUM2INT(protocol);
     ret = rsock_socketpair(d, t, p, sp);
     if (ret < 0) {
-	rb_sys_fail("socketpair(2)");
+        rb_sys_fail("socketpair(2)");
     }
 
     s1 = rsock_init_sock(rb_obj_alloc(klass), sp[0]);
@@ -395,7 +399,7 @@ sock_connect(VALUE sock, VALUE addr)
     fd = fptr->fd;
     n = rsock_connect(fd, (struct sockaddr*)RSTRING_PTR(addr), RSTRING_SOCKLEN(addr), 0, NULL);
     if (n < 0) {
-	rsock_sys_fail_raddrinfo_or_sockaddr("connect(2)", addr, rai);
+        rsock_sys_fail_raddrinfo_or_sockaddr("connect(2)", addr, rai);
     }
 
     return INT2FIX(n);
@@ -415,19 +419,19 @@ sock_connect_nonblock(VALUE sock, VALUE addr, VALUE ex)
     rb_io_set_nonblock(fptr);
     n = connect(fptr->fd, (struct sockaddr*)RSTRING_PTR(addr), RSTRING_SOCKLEN(addr));
     if (n < 0) {
-	int e = errno;
-	if (e == EINPROGRESS) {
+        int e = errno;
+        if (e == EINPROGRESS) {
             if (ex == Qfalse) {
                 return sym_wait_writable;
             }
             rb_readwrite_syserr_fail(RB_IO_WAIT_WRITABLE, e, "connect(2) would block");
-	}
-	if (e == EISCONN) {
+        }
+        if (e == EISCONN) {
             if (ex == Qfalse) {
                 return INT2FIX(0);
             }
-	}
-	rsock_syserr_fail_raddrinfo_or_sockaddr(e, "connect(2)", addr, rai);
+        }
+        rsock_syserr_fail_raddrinfo_or_sockaddr(e, "connect(2)", addr, rai);
     }
 
     return INT2FIX(n);
@@ -528,7 +532,7 @@ sock_bind(VALUE sock, VALUE addr)
     SockAddrStringValueWithAddrinfo(addr, rai);
     GetOpenFile(sock, fptr);
     if (bind(fptr->fd, (struct sockaddr*)RSTRING_PTR(addr), RSTRING_SOCKLEN(addr)) < 0)
-	rsock_sys_fail_raddrinfo_or_sockaddr("bind(2)", addr, rai);
+        rsock_sys_fail_raddrinfo_or_sockaddr("bind(2)", addr, rai);
 
     return INT2FIX(0);
 }
@@ -612,7 +616,7 @@ rsock_sock_listen(VALUE sock, VALUE log)
     backlog = NUM2INT(log);
     GetOpenFile(sock, fptr);
     if (listen(fptr->fd, backlog) < 0)
-	rb_sys_fail("listen(2)");
+        rb_sys_fail("listen(2)");
 
     return INT2FIX(0);
 }
@@ -774,7 +778,7 @@ sock_accept_nonblock(VALUE sock, VALUE ex)
     sock2 = rsock_s_accept_nonblock(rb_cSocket, ex, fptr, addr, &len);
 
     if (SYMBOL_P(sock2)) /* :wait_readable */
-	return sock2;
+        return sock2;
     return rb_assoc_new(sock2, rsock_io_socket_addrinfo(sock2, &buf.addr, len));
 }
 
@@ -855,19 +859,19 @@ sock_gethostname(VALUE obj)
 
     name = rb_str_new(0, len);
     while (gethostname(RSTRING_PTR(name), len) < 0) {
-	int e = errno;
-	switch (e) {
-	  case ENAMETOOLONG:
+        int e = errno;
+        switch (e) {
+          case ENAMETOOLONG:
 #ifdef __linux__
-	  case EINVAL:
-	    /* glibc before version 2.1 uses EINVAL instead of ENAMETOOLONG */
+          case EINVAL:
+            /* glibc before version 2.1 uses EINVAL instead of ENAMETOOLONG */
 #endif
-	    break;
-	  default:
-	    rb_syserr_fail(e, "gethostname(3)");
-	}
-	rb_str_modify_expand(name, len);
-	len += len;
+            break;
+          default:
+            rb_syserr_fail(e, "gethostname(3)");
+        }
+        rb_str_modify_expand(name, len);
+        len += len;
     }
     rb_str_resize(name, strlen(RSTRING_PTR(name)));
     return name;
@@ -897,18 +901,18 @@ make_addrinfo(struct rb_addrinfo *res0, int norevlookup)
     struct addrinfo *res;
 
     if (res0 == NULL) {
-	rb_raise(rb_eSocket, "host not found");
+        rb_raise(rb_eSocket, "host not found");
     }
     base = rb_ary_new();
     for (res = res0->ai; res; res = res->ai_next) {
-	ary = rsock_ipaddr(res->ai_addr, res->ai_addrlen, norevlookup);
-	if (res->ai_canonname) {
-	    RARRAY_ASET(ary, 2, rb_str_new2(res->ai_canonname));
-	}
-	rb_ary_push(ary, INT2FIX(res->ai_family));
-	rb_ary_push(ary, INT2FIX(res->ai_socktype));
-	rb_ary_push(ary, INT2FIX(res->ai_protocol));
-	rb_ary_push(base, ary);
+        ary = rsock_ipaddr(res->ai_addr, res->ai_addrlen, norevlookup);
+        if (res->ai_canonname) {
+            RARRAY_ASET(ary, 2, rb_str_new2(res->ai_canonname));
+        }
+        rb_ary_push(ary, INT2FIX(res->ai_family));
+        rb_ary_push(ary, INT2FIX(res->ai_socktype));
+        rb_ary_push(ary, INT2FIX(res->ai_protocol));
+        rb_ary_push(base, ary);
     }
     return base;
 }
@@ -920,18 +924,18 @@ sock_sockaddr(struct sockaddr *addr, socklen_t len)
 
     switch (addr->sa_family) {
       case AF_INET:
-	ptr = (char*)&((struct sockaddr_in*)addr)->sin_addr.s_addr;
-	len = (socklen_t)sizeof(((struct sockaddr_in*)addr)->sin_addr.s_addr);
-	break;
+        ptr = (char*)&((struct sockaddr_in*)addr)->sin_addr.s_addr;
+        len = (socklen_t)sizeof(((struct sockaddr_in*)addr)->sin_addr.s_addr);
+        break;
 #ifdef AF_INET6
       case AF_INET6:
-	ptr = (char*)&((struct sockaddr_in6*)addr)->sin6_addr.s6_addr;
-	len = (socklen_t)sizeof(((struct sockaddr_in6*)addr)->sin6_addr.s6_addr);
-	break;
+        ptr = (char*)&((struct sockaddr_in6*)addr)->sin6_addr.s6_addr;
+        len = (socklen_t)sizeof(((struct sockaddr_in6*)addr)->sin6_addr.s6_addr);
+        break;
 #endif
       default:
         rb_raise(rb_eSocket, "unknown socket family:%d", addr->sa_family);
-	break;
+        break;
     }
     return rb_str_new(ptr, len);
 }
@@ -961,7 +965,7 @@ sock_s_gethostbyname(VALUE obj, VALUE host)
 {
     rb_warn("Socket.gethostbyname is deprecated; use Addrinfo.getaddrinfo instead.");
     struct rb_addrinfo *res =
-	rsock_addrinfo(host, Qnil, AF_UNSPEC, SOCK_STREAM, AI_CANONNAME);
+        rsock_addrinfo(host, Qnil, AF_UNSPEC, SOCK_STREAM, AI_CANONNAME);
     return rsock_make_hostent(host, res, sock_sockaddr);
 }
 
@@ -1004,20 +1008,20 @@ sock_s_gethostbyaddr(int argc, VALUE *argv, VALUE _)
     rb_scan_args(argc, argv, "11", &addr, &family);
     StringValue(addr);
     if (!NIL_P(family)) {
-	t = rsock_family_arg(family);
+        t = rsock_family_arg(family);
     }
 #ifdef AF_INET6
     else if (RSTRING_LEN(addr) == 16) {
-	t = AF_INET6;
+        t = AF_INET6;
     }
 #endif
     h = gethostbyaddr(RSTRING_PTR(addr), RSTRING_SOCKLEN(addr), t);
     if (h == NULL) {
 #ifdef HAVE_HSTRERROR
-	extern int h_errno;
-	rb_raise(rb_eSocket, "%s", (char*)hstrerror(h_errno));
+        extern int h_errno;
+        rb_raise(rb_eSocket, "%s", (char*)hstrerror(h_errno));
 #else
-	rb_raise(rb_eSocket, "host not found");
+        rb_raise(rb_eSocket, "host not found");
 #endif
     }
     ary = rb_ary_new();
@@ -1025,14 +1029,14 @@ sock_s_gethostbyaddr(int argc, VALUE *argv, VALUE _)
     names = rb_ary_new();
     rb_ary_push(ary, names);
     if (h->h_aliases != NULL) {
-	for (pch = h->h_aliases; *pch; pch++) {
-	    rb_ary_push(names, rb_str_new2(*pch));
-	}
+        for (pch = h->h_aliases; *pch; pch++) {
+            rb_ary_push(names, rb_str_new2(*pch));
+        }
     }
     rb_ary_push(ary, INT2NUM(h->h_addrtype));
 #ifdef h_addr
     for (pch = h->h_addr_list; *pch; pch++) {
-	rb_ary_push(ary, rb_str_new(*pch, h->h_length));
+        rb_ary_push(ary, rb_str_new(*pch, h->h_length));
     }
 #else
     rb_ary_push(ary, rb_str_new(h->h_addr, h->h_length));
@@ -1069,15 +1073,15 @@ sock_s_getservbyname(int argc, VALUE *argv, VALUE _)
     if (!NIL_P(proto)) protoname = StringValueCStr(proto);
     sp = getservbyname(servicename, protoname);
     if (sp) {
-	port = ntohs(sp->s_port);
+        port = ntohs(sp->s_port);
     }
     else {
-	char *end;
+        char *end;
 
-	port = STRTOUL(servicename, &end, 0);
-	if (*end != '\0') {
-	    rb_raise(rb_eSocket, "no such service %s/%s", servicename, protoname);
-	}
+        port = STRTOUL(servicename, &end, 0);
+        if (*end != '\0') {
+            rb_raise(rb_eSocket, "no such service %s/%s", servicename, protoname);
+        }
     }
     return INT2FIX(port);
 }
@@ -1106,14 +1110,14 @@ sock_s_getservbyport(int argc, VALUE *argv, VALUE _)
     rb_scan_args(argc, argv, "11", &port, &proto);
     portnum = NUM2LONG(port);
     if (portnum != (uint16_t)portnum) {
-	const char *s = portnum > 0 ? "big" : "small";
-	rb_raise(rb_eRangeError, "integer %ld too %s to convert into `int16_t'", portnum, s);
+        const char *s = portnum > 0 ? "big" : "small";
+        rb_raise(rb_eRangeError, "integer %ld too %s to convert into `int16_t'", portnum, s);
     }
     if (!NIL_P(proto)) protoname = StringValueCStr(proto);
 
     sp = getservbyport((int)htons((uint16_t)portnum), protoname);
     if (!sp) {
-	rb_raise(rb_eSocket, "no such service for port %d/%s", (int)portnum, protoname);
+        rb_raise(rb_eSocket, "no such service for port %d/%s", (int)portnum, protoname);
     }
     return rb_str_new2(sp->s_name);
 }
@@ -1167,16 +1171,16 @@ sock_s_getaddrinfo(int argc, VALUE *argv, VALUE _)
     hints.ai_family = NIL_P(family) ? PF_UNSPEC : rsock_family_arg(family);
 
     if (!NIL_P(socktype)) {
-	hints.ai_socktype = rsock_socktype_arg(socktype);
+        hints.ai_socktype = rsock_socktype_arg(socktype);
     }
     if (!NIL_P(protocol)) {
-	hints.ai_protocol = NUM2INT(protocol);
+        hints.ai_protocol = NUM2INT(protocol);
     }
     if (!NIL_P(flags)) {
-	hints.ai_flags = NUM2INT(flags);
+        hints.ai_flags = NUM2INT(flags);
     }
     if (NIL_P(revlookup) || !rsock_revlookup_flag(revlookup, &norevlookup)) {
-	norevlookup = rsock_do_not_reverse_lookup;
+        norevlookup = rsock_do_not_reverse_lookup;
     }
 
     res = rsock_getaddrinfo(host, port, &hints, 0);
@@ -1226,82 +1230,82 @@ sock_s_getnameinfo(int argc, VALUE *argv, VALUE _)
 
     fl = 0;
     if (!NIL_P(flags)) {
-	fl = NUM2INT(flags);
+        fl = NUM2INT(flags);
     }
     tmp = rb_check_sockaddr_string_type(sa);
     if (!NIL_P(tmp)) {
-	sa = tmp;
-	if (sizeof(ss) < (size_t)RSTRING_LEN(sa)) {
-	    rb_raise(rb_eTypeError, "sockaddr length too big");
-	}
-	memcpy(&ss, RSTRING_PTR(sa), RSTRING_LEN(sa));
+        sa = tmp;
+        if (sizeof(ss) < (size_t)RSTRING_LEN(sa)) {
+            rb_raise(rb_eTypeError, "sockaddr length too big");
+        }
+        memcpy(&ss, RSTRING_PTR(sa), RSTRING_LEN(sa));
         if (!VALIDATE_SOCKLEN(&ss.addr, RSTRING_LEN(sa))) {
-	    rb_raise(rb_eTypeError, "sockaddr size differs - should not happen");
-	}
-	sap = &ss.addr;
+            rb_raise(rb_eTypeError, "sockaddr size differs - should not happen");
+        }
+        sap = &ss.addr;
         salen = RSTRING_SOCKLEN(sa);
-	goto call_nameinfo;
+        goto call_nameinfo;
     }
     tmp = rb_check_array_type(sa);
     if (!NIL_P(tmp)) {
-	sa = tmp;
-	MEMZERO(&hints, struct addrinfo, 1);
-	if (RARRAY_LEN(sa) == 3) {
-	    af = RARRAY_AREF(sa, 0);
-	    port = RARRAY_AREF(sa, 1);
-	    host = RARRAY_AREF(sa, 2);
-	}
-	else if (RARRAY_LEN(sa) >= 4) {
-	    af = RARRAY_AREF(sa, 0);
-	    port = RARRAY_AREF(sa, 1);
-	    host = RARRAY_AREF(sa, 3);
-	    if (NIL_P(host)) {
-		host = RARRAY_AREF(sa, 2);
-	    }
-	    else {
-		/*
-		 * 4th element holds numeric form, don't resolve.
-		 * see rsock_ipaddr().
-		 */
+        sa = tmp;
+        MEMZERO(&hints, struct addrinfo, 1);
+        if (RARRAY_LEN(sa) == 3) {
+            af = RARRAY_AREF(sa, 0);
+            port = RARRAY_AREF(sa, 1);
+            host = RARRAY_AREF(sa, 2);
+        }
+        else if (RARRAY_LEN(sa) >= 4) {
+            af = RARRAY_AREF(sa, 0);
+            port = RARRAY_AREF(sa, 1);
+            host = RARRAY_AREF(sa, 3);
+            if (NIL_P(host)) {
+                host = RARRAY_AREF(sa, 2);
+            }
+            else {
+                /*
+                 * 4th element holds numeric form, don't resolve.
+                 * see rsock_ipaddr().
+                 */
 #ifdef AI_NUMERICHOST /* AIX 4.3.3 doesn't have AI_NUMERICHOST. */
-		hints.ai_flags |= AI_NUMERICHOST;
+                hints.ai_flags |= AI_NUMERICHOST;
 #endif
-	    }
-	}
-	else {
-	    rb_raise(rb_eArgError, "array size should be 3 or 4, %ld given",
-		     RARRAY_LEN(sa));
-	}
-	hints.ai_socktype = (fl & NI_DGRAM) ? SOCK_DGRAM : SOCK_STREAM;
-	/* af */
+            }
+        }
+        else {
+            rb_raise(rb_eArgError, "array size should be 3 or 4, %ld given",
+                     RARRAY_LEN(sa));
+        }
+        hints.ai_socktype = (fl & NI_DGRAM) ? SOCK_DGRAM : SOCK_STREAM;
+        /* af */
         hints.ai_family = NIL_P(af) ? PF_UNSPEC : rsock_family_arg(af);
-	res = rsock_getaddrinfo(host, port, &hints, 0);
-	sap = res->ai->ai_addr;
+        res = rsock_getaddrinfo(host, port, &hints, 0);
+        sap = res->ai->ai_addr;
         salen = res->ai->ai_addrlen;
     }
     else {
-	rb_raise(rb_eTypeError, "expecting String or Array");
+        rb_raise(rb_eTypeError, "expecting String or Array");
     }
 
   call_nameinfo:
     error = rb_getnameinfo(sap, salen, hbuf, sizeof(hbuf),
-			   pbuf, sizeof(pbuf), fl);
+                           pbuf, sizeof(pbuf), fl);
     if (error) goto error_exit_name;
     if (res) {
-	for (r = res->ai->ai_next; r; r = r->ai_next) {
-	    char hbuf2[1024], pbuf2[1024];
+        for (r = res->ai->ai_next; r; r = r->ai_next) {
+            char hbuf2[1024], pbuf2[1024];
 
-	    sap = r->ai_addr;
+            sap = r->ai_addr;
             salen = r->ai_addrlen;
-	    error = rb_getnameinfo(sap, salen, hbuf2, sizeof(hbuf2),
-				   pbuf2, sizeof(pbuf2), fl);
-	    if (error) goto error_exit_name;
-	    if (strcmp(hbuf, hbuf2) != 0|| strcmp(pbuf, pbuf2) != 0) {
-		rb_freeaddrinfo(res);
-		rb_raise(rb_eSocket, "sockaddr resolved to multiple nodename");
-	    }
-	}
-	rb_freeaddrinfo(res);
+            error = rb_getnameinfo(sap, salen, hbuf2, sizeof(hbuf2),
+                                   pbuf2, sizeof(pbuf2), fl);
+            if (error) goto error_exit_name;
+            if (strcmp(hbuf, hbuf2) != 0|| strcmp(pbuf, pbuf2) != 0) {
+                rb_freeaddrinfo(res);
+                rb_raise(rb_eSocket, "sockaddr resolved to multiple nodename");
+            }
+        }
+        rb_freeaddrinfo(res);
     }
     return rb_assoc_new(rb_str_new2(hbuf), rb_str_new2(pbuf));
 
@@ -1379,7 +1383,7 @@ sock_s_unpack_sockaddr_in(VALUE self, VALUE addr)
     return rb_assoc_new(INT2NUM(ntohs(sockaddr->sin_port)), host);
 }
 
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
 
 /*
  * call-seq:
@@ -1437,8 +1441,8 @@ sock_s_unpack_sockaddr_un(VALUE self, VALUE addr)
         rb_raise(rb_eArgError, "not an AF_UNIX sockaddr");
     }
     if (sizeof(struct sockaddr_un) < (size_t)RSTRING_LEN(addr)) {
-	rb_raise(rb_eTypeError, "too long sockaddr_un - %ld longer than %d",
-		 RSTRING_LEN(addr), (int)sizeof(struct sockaddr_un));
+        rb_raise(rb_eTypeError, "too long sockaddr_un - %ld longer than %d",
+                 RSTRING_LEN(addr), (int)sizeof(struct sockaddr_un));
     }
     path = rsock_unixpath_str(sockaddr, RSTRING_SOCKLEN(addr));
     return path;
@@ -1467,7 +1471,7 @@ sockaddr_len(struct sockaddr *addr)
         return (socklen_t)sizeof(struct sockaddr_in6);
 #endif
 
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
       case AF_UNIX:
         return (socklen_t)sizeof(struct sockaddr_un);
 #endif
@@ -1502,19 +1506,19 @@ sockaddr_obj(struct sockaddr *addr, socklen_t len)
 
 #if defined(__KAME__) && defined(AF_INET6)
     if (addr->sa_family == AF_INET6) {
-	/* KAME uses the 2nd 16bit word of link local IPv6 address as interface index internally */
+        /* KAME uses the 2nd 16bit word of link local IPv6 address as interface index internally */
         /* http://orange.kame.net/dev/cvsweb.cgi/kame/IMPLEMENTATION */
-	/* convert fe80:1::1 to fe80::1%1 */
+        /* convert fe80:1::1 to fe80::1%1 */
         len = (socklen_t)sizeof(struct sockaddr_in6);
-	memcpy(&addr6, addr, len);
-	addr = (struct sockaddr *)&addr6;
-	if (IN6_IS_ADDR_LINKLOCAL(&addr6.sin6_addr) &&
-	    addr6.sin6_scope_id == 0 &&
-	    (addr6.sin6_addr.s6_addr[2] || addr6.sin6_addr.s6_addr[3])) {
-	    addr6.sin6_scope_id = (addr6.sin6_addr.s6_addr[2] << 8) | addr6.sin6_addr.s6_addr[3];
-	    addr6.sin6_addr.s6_addr[2] = 0;
-	    addr6.sin6_addr.s6_addr[3] = 0;
-	}
+        memcpy(&addr6, addr, len);
+        addr = (struct sockaddr *)&addr6;
+        if (IN6_IS_ADDR_LINKLOCAL(&addr6.sin6_addr) &&
+            addr6.sin6_scope_id == 0 &&
+            (addr6.sin6_addr.s6_addr[2] || addr6.sin6_addr.s6_addr[3])) {
+            addr6.sin6_scope_id = (addr6.sin6_addr.s6_addr[2] << 8) | addr6.sin6_addr.s6_addr[3];
+            addr6.sin6_addr.s6_addr[2] = 0;
+            addr6.sin6_addr.s6_addr[3] = 0;
+        }
     }
 #endif
 
@@ -1612,8 +1616,8 @@ socket_s_ip_address_list(VALUE self)
 
     ret = ioctl(fd, SIOCGLIFNUM, &ln);
     if (ret == -1) {
-	reason = "SIOCGLIFNUM";
-	goto finish;
+        reason = "SIOCGLIFNUM";
+        goto finish;
     }
 
     memset(&lc, 0, sizeof(lc));
@@ -1624,13 +1628,13 @@ socket_s_ip_address_list(VALUE self)
 
     ret = ioctl(fd, SIOCGLIFCONF, &lc);
     if (ret == -1) {
-	reason = "SIOCGLIFCONF";
-	goto finish;
+        reason = "SIOCGLIFCONF";
+        goto finish;
     }
 
     list = rb_ary_new();
     for (i = 0; i < ln.lifn_count; i++) {
-	struct lifreq *req = &lc.lifc_req[i];
+        struct lifreq *req = &lc.lifc_req[i];
         if (IS_IP_FAMILY(req->lifr_addr.ss_family)) {
             if (req->lifr_addr.ss_family == AF_INET6 &&
                 IN6_IS_ADDR_LINKLOCAL(&((struct sockaddr_in6 *)(&req->lifr_addr))->sin6_addr) &&
@@ -1651,13 +1655,13 @@ socket_s_ip_address_list(VALUE self)
   finish:
     save_errno = errno;
     if (lc.lifc_buf != NULL)
-	xfree(lc.lifc_req);
+        xfree(lc.lifc_req);
     if (fd != -1)
-	close(fd);
+        close(fd);
     errno = save_errno;
 
     if (reason)
-	rb_syserr_fail(save_errno, reason);
+        rb_syserr_fail(save_errno, reason);
     return list;
 
 #elif defined(SIOCGIFCONF)
@@ -1695,17 +1699,17 @@ socket_s_ip_address_list(VALUE self)
     /* fprintf(stderr, "conf.ifc_len: %d\n", conf.ifc_len); */
 
     if (bufsize - EXTRA_SPACE < conf.ifc_len) {
-	if (bufsize < conf.ifc_len) {
-	    /* NetBSD returns required size for all interfaces. */
-	    bufsize = conf.ifc_len + EXTRA_SPACE;
-	}
-	else {
-	    bufsize = bufsize << 1;
-	}
-	if (buf == initbuf)
-	    buf = NULL;
-	buf = xrealloc(buf, bufsize);
-	goto retry;
+        if (bufsize < conf.ifc_len) {
+            /* NetBSD returns required size for all interfaces. */
+            bufsize = conf.ifc_len + EXTRA_SPACE;
+        }
+        else {
+            bufsize = bufsize << 1;
+        }
+        if (buf == initbuf)
+            buf = NULL;
+        buf = xrealloc(buf, bufsize);
+        goto retry;
     }
 
     close(fd);
@@ -1714,10 +1718,10 @@ socket_s_ip_address_list(VALUE self)
     list = rb_ary_new();
     req = conf.ifc_req;
     while ((char*)req < (char*)conf.ifc_req + conf.ifc_len) {
-	struct sockaddr *addr = &req->ifr_addr;
+        struct sockaddr *addr = &req->ifr_addr;
         if (IS_IP_FAMILY(addr->sa_family)) {
-	    rb_ary_push(list, sockaddr_obj(addr, sockaddr_len(addr)));
-	}
+            rb_ary_push(list, sockaddr_obj(addr, sockaddr_len(addr)));
+        }
 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
 # ifndef _SIZEOF_ADDR_IFREQ
 #  define _SIZEOF_ADDR_IFREQ(r) \
@@ -1726,9 +1730,9 @@ socket_s_ip_address_list(VALUE self)
             (r).ifr_addr.sa_len - sizeof(struct sockaddr) : \
             0))
 # endif
-	req = (struct ifreq *)((char*)req + _SIZEOF_ADDR_IFREQ(*req));
+        req = (struct ifreq *)((char*)req + _SIZEOF_ADDR_IFREQ(*req));
 #else
-	req = (struct ifreq *)((char*)req + sizeof(struct ifreq));
+        req = (struct ifreq *)((char*)req + sizeof(struct ifreq));
 #endif
     }
 
@@ -1738,57 +1742,57 @@ socket_s_ip_address_list(VALUE self)
     if (buf != initbuf)
         xfree(buf);
     if (fd != -1)
-	close(fd);
+        close(fd);
     errno = save_errno;
 
     if (reason)
-	rb_syserr_fail(save_errno, reason);
+        rb_syserr_fail(save_errno, reason);
     return list;
 
 #undef EXTRA_SPACE
 #elif defined(_WIN32)
     typedef struct ip_adapter_unicast_address_st {
-	unsigned LONG_LONG dummy0;
-	struct ip_adapter_unicast_address_st *Next;
-	struct {
-	    struct sockaddr *lpSockaddr;
-	    int iSockaddrLength;
-	} Address;
-	int dummy1;
-	int dummy2;
-	int dummy3;
-	long dummy4;
-	long dummy5;
-	long dummy6;
+        unsigned LONG_LONG dummy0;
+        struct ip_adapter_unicast_address_st *Next;
+        struct {
+            struct sockaddr *lpSockaddr;
+            int iSockaddrLength;
+        } Address;
+        int dummy1;
+        int dummy2;
+        int dummy3;
+        long dummy4;
+        long dummy5;
+        long dummy6;
     } ip_adapter_unicast_address_t;
     typedef struct ip_adapter_anycast_address_st {
-	unsigned LONG_LONG dummy0;
-	struct ip_adapter_anycast_address_st *Next;
-	struct {
-	    struct sockaddr *lpSockaddr;
-	    int iSockaddrLength;
-	} Address;
+        unsigned LONG_LONG dummy0;
+        struct ip_adapter_anycast_address_st *Next;
+        struct {
+            struct sockaddr *lpSockaddr;
+            int iSockaddrLength;
+        } Address;
     } ip_adapter_anycast_address_t;
     typedef struct ip_adapter_addresses_st {
-	unsigned LONG_LONG dummy0;
-	struct ip_adapter_addresses_st *Next;
-	void *dummy1;
-	ip_adapter_unicast_address_t *FirstUnicastAddress;
-	ip_adapter_anycast_address_t *FirstAnycastAddress;
-	void *dummy2;
-	void *dummy3;
-	void *dummy4;
-	void *dummy5;
-	void *dummy6;
-	BYTE dummy7[8];
-	DWORD dummy8;
-	DWORD dummy9;
-	DWORD dummy10;
-	DWORD IfType;
-	int OperStatus;
-	DWORD dummy12;
-	DWORD dummy13[16];
-	void *dummy14;
+        unsigned LONG_LONG dummy0;
+        struct ip_adapter_addresses_st *Next;
+        void *dummy1;
+        ip_adapter_unicast_address_t *FirstUnicastAddress;
+        ip_adapter_anycast_address_t *FirstAnycastAddress;
+        void *dummy2;
+        void *dummy3;
+        void *dummy4;
+        void *dummy5;
+        void *dummy6;
+        BYTE dummy7[8];
+        DWORD dummy8;
+        DWORD dummy9;
+        DWORD dummy10;
+        DWORD IfType;
+        int OperStatus;
+        DWORD dummy12;
+        DWORD dummy13[16];
+        void *dummy14;
     } ip_adapter_addresses_t;
     typedef ULONG (WINAPI *GetAdaptersAddresses_t)(ULONG, ULONG, PVOID, ip_adapter_addresses_t *, PULONG);
     HMODULE h;
@@ -1800,49 +1804,49 @@ socket_s_ip_address_list(VALUE self)
 
     h = LoadLibrary("iphlpapi.dll");
     if (!h)
-	rb_notimplement();
+        rb_notimplement();
     pGetAdaptersAddresses = (GetAdaptersAddresses_t)GetProcAddress(h, "GetAdaptersAddresses");
     if (!pGetAdaptersAddresses) {
-	FreeLibrary(h);
-	rb_notimplement();
+        FreeLibrary(h);
+        rb_notimplement();
     }
 
     ret = pGetAdaptersAddresses(AF_UNSPEC, 0, NULL, NULL, &len);
     if (ret != ERROR_SUCCESS && ret != ERROR_BUFFER_OVERFLOW) {
-	errno = rb_w32_map_errno(ret);
-	FreeLibrary(h);
-	rb_sys_fail("GetAdaptersAddresses");
+        errno = rb_w32_map_errno(ret);
+        FreeLibrary(h);
+        rb_sys_fail("GetAdaptersAddresses");
     }
     adapters = (ip_adapter_addresses_t *)ALLOCA_N(BYTE, len);
     ret = pGetAdaptersAddresses(AF_UNSPEC, 0, NULL, adapters, &len);
     if (ret != ERROR_SUCCESS) {
-	errno = rb_w32_map_errno(ret);
-	FreeLibrary(h);
-	rb_sys_fail("GetAdaptersAddresses");
+        errno = rb_w32_map_errno(ret);
+        FreeLibrary(h);
+        rb_sys_fail("GetAdaptersAddresses");
     }
 
     list = rb_ary_new();
     for (; adapters; adapters = adapters->Next) {
-	ip_adapter_unicast_address_t *uni;
-	ip_adapter_anycast_address_t *any;
-	if (adapters->OperStatus != 1)	/* 1 means IfOperStatusUp */
-	    continue;
-	for (uni = adapters->FirstUnicastAddress; uni; uni = uni->Next) {
+        ip_adapter_unicast_address_t *uni;
+        ip_adapter_anycast_address_t *any;
+        if (adapters->OperStatus != 1)	/* 1 means IfOperStatusUp */
+            continue;
+        for (uni = adapters->FirstUnicastAddress; uni; uni = uni->Next) {
 #ifndef INET6
-	    if (uni->Address.lpSockaddr->sa_family == AF_INET)
+            if (uni->Address.lpSockaddr->sa_family == AF_INET)
 #else
-	    if (IS_IP_FAMILY(uni->Address.lpSockaddr->sa_family))
+            if (IS_IP_FAMILY(uni->Address.lpSockaddr->sa_family))
 #endif
-		rb_ary_push(list, sockaddr_obj(uni->Address.lpSockaddr, uni->Address.iSockaddrLength));
-	}
-	for (any = adapters->FirstAnycastAddress; any; any = any->Next) {
+                rb_ary_push(list, sockaddr_obj(uni->Address.lpSockaddr, uni->Address.iSockaddrLength));
+        }
+        for (any = adapters->FirstAnycastAddress; any; any = any->Next) {
 #ifndef INET6
-	    if (any->Address.lpSockaddr->sa_family == AF_INET)
+            if (any->Address.lpSockaddr->sa_family == AF_INET)
 #else
-	    if (IS_IP_FAMILY(any->Address.lpSockaddr->sa_family))
+            if (IS_IP_FAMILY(any->Address.lpSockaddr->sa_family))
 #endif
-		rb_ary_push(list, sockaddr_obj(any->Address.lpSockaddr, any->Address.iSockaddrLength));
-	}
+                rb_ary_push(list, sockaddr_obj(any->Address.lpSockaddr, any->Address.iSockaddrLength));
+        }
     }
 
     FreeLibrary(h);
@@ -1986,7 +1990,7 @@ Init_socket(void)
 
     /* for ext/socket/lib/socket.rb use only: */
     rb_define_private_method(rb_cSocket,
-			     "__connect_nonblock", sock_connect_nonblock, 2);
+                             "__connect_nonblock", sock_connect_nonblock, 2);
 
     rb_define_method(rb_cSocket, "bind", sock_bind, 1);
     rb_define_method(rb_cSocket, "listen", rsock_sock_listen, 1);
@@ -1994,7 +1998,7 @@ Init_socket(void)
 
     /* for ext/socket/lib/socket.rb use only: */
     rb_define_private_method(rb_cSocket,
-			     "__accept_nonblock", sock_accept_nonblock, 1);
+                             "__accept_nonblock", sock_accept_nonblock, 1);
 
     rb_define_method(rb_cSocket, "sysaccept", sock_sysaccept, 0);
 
@@ -2002,7 +2006,7 @@ Init_socket(void)
 
     /* for ext/socket/lib/socket.rb use only: */
     rb_define_private_method(rb_cSocket,
-			     "__recvfrom_nonblock", sock_recvfrom_nonblock, 4);
+                             "__recvfrom_nonblock", sock_recvfrom_nonblock, 4);
 
     rb_define_singleton_method(rb_cSocket, "socketpair", rsock_sock_s_socketpair, -1);
     rb_define_singleton_method(rb_cSocket, "pair", rsock_sock_s_socketpair, -1);
@@ -2016,7 +2020,7 @@ Init_socket(void)
     rb_define_singleton_method(rb_cSocket, "sockaddr_in", sock_s_pack_sockaddr_in, 2);
     rb_define_singleton_method(rb_cSocket, "pack_sockaddr_in", sock_s_pack_sockaddr_in, 2);
     rb_define_singleton_method(rb_cSocket, "unpack_sockaddr_in", sock_s_unpack_sockaddr_in, 1);
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
     rb_define_singleton_method(rb_cSocket, "sockaddr_un", sock_s_pack_sockaddr_un, 1);
     rb_define_singleton_method(rb_cSocket, "pack_sockaddr_un", sock_s_pack_sockaddr_un, 1);
     rb_define_singleton_method(rb_cSocket, "unpack_sockaddr_un", sock_s_unpack_sockaddr_un, 1);
diff --git a/ext/socket/sockssocket.c b/ext/socket/sockssocket.c
index b8b7e12998..f263ac3804 100644
--- a/ext/socket/sockssocket.c
+++ b/ext/socket/sockssocket.c
@@ -30,8 +30,8 @@ socks_init(VALUE sock, VALUE host, VALUE port)
     static int init = 0;
 
     if (init == 0) {
-	SOCKSinit("ruby");
-	init = 1;
+        SOCKSinit("ruby");
+        init = 1;
     }
 
     return rsock_init_inetsock(sock, host, port, Qnil, Qnil, INET_SOCKS, Qnil, Qnil);
diff --git a/ext/socket/tcpserver.c b/ext/socket/tcpserver.c
index 675733c6f9..04e5a0bb51 100644
--- a/ext/socket/tcpserver.c
+++ b/ext/socket/tcpserver.c
@@ -133,7 +133,7 @@ rsock_init_tcpserver(void)
     rb_cTCPServer = rb_define_class("TCPServer", rb_cTCPSocket);
     rb_define_method(rb_cTCPServer, "accept", tcp_accept, 0);
     rb_define_private_method(rb_cTCPServer,
-			     "__accept_nonblock", tcp_accept_nonblock, 1);
+                             "__accept_nonblock", tcp_accept_nonblock, 1);
     rb_define_method(rb_cTCPServer, "sysaccept", tcp_sysaccept, 0);
     rb_define_method(rb_cTCPServer, "initialize", tcp_svr_init, -1);
     rb_define_method(rb_cTCPServer, "listen", rsock_sock_listen, 1); /* in socket.c */
diff --git a/ext/socket/tcpsocket.c b/ext/socket/tcpsocket.c
index 51e77a0de9..03787272f3 100644
--- a/ext/socket/tcpsocket.c
+++ b/ext/socket/tcpsocket.c
@@ -32,22 +32,22 @@ tcp_init(int argc, VALUE *argv, VALUE sock)
     VALUE connect_timeout = Qnil;
 
     if (!keyword_ids[0]) {
-	CONST_ID(keyword_ids[0], "resolv_timeout");
-	CONST_ID(keyword_ids[1], "connect_timeout");
+        CONST_ID(keyword_ids[0], "resolv_timeout");
+        CONST_ID(keyword_ids[1], "connect_timeout");
     }
 
     rb_scan_args(argc, argv, "22:", &remote_host, &remote_serv,
-			&local_host, &local_serv, &opt);
+                        &local_host, &local_serv, &opt);
 
     if (!NIL_P(opt)) {
-	rb_get_kwargs(opt, keyword_ids, 0, 2, kwargs);
-	if (kwargs[0] != Qundef) { resolv_timeout = kwargs[0]; }
-	if (kwargs[1] != Qundef) { connect_timeout = kwargs[1]; }
+        rb_get_kwargs(opt, keyword_ids, 0, 2, kwargs);
+        if (kwargs[0] != Qundef) { resolv_timeout = kwargs[0]; }
+        if (kwargs[1] != Qundef) { connect_timeout = kwargs[1]; }
     }
 
     return rsock_init_inetsock(sock, remote_host, remote_serv,
-			       local_host, local_serv, INET_CLIENT,
-			       resolv_timeout, connect_timeout);
+                               local_host, local_serv, INET_CLIENT,
+                               resolv_timeout, connect_timeout);
 }
 
 static VALUE
@@ -80,7 +80,7 @@ tcp_s_gethostbyname(VALUE obj, VALUE host)
 {
     rb_warn("TCPSocket.gethostbyname is deprecated; use Addrinfo.getaddrinfo instead.");
     struct rb_addrinfo *res =
-	rsock_addrinfo(host, Qnil, AF_UNSPEC, SOCK_STREAM, AI_CANONNAME);
+        rsock_addrinfo(host, Qnil, AF_UNSPEC, SOCK_STREAM, AI_CANONNAME);
     return rsock_make_hostent(host, res, tcp_sockaddr);
 }
 
diff --git a/ext/socket/udpsocket.c b/ext/socket/udpsocket.c
index 2bfd7c8560..5224e48a96 100644
--- a/ext/socket/udpsocket.c
+++ b/ext/socket/udpsocket.c
@@ -33,11 +33,11 @@ udp_init(int argc, VALUE *argv, VALUE sock)
     int fd;
 
     if (rb_scan_args(argc, argv, "01", &arg) == 1) {
-	family = rsock_family_arg(arg);
+        family = rsock_family_arg(arg);
     }
     fd = rsock_socket(family, SOCK_DGRAM, 0);
     if (fd < 0) {
-	rb_sys_fail("socket(2) - udp");
+        rb_sys_fail("socket(2) - udp");
     }
 
     return rsock_init_sock(sock, fd);
@@ -60,9 +60,9 @@ udp_connect_internal(VALUE v)
     rb_io_check_closed(fptr = arg->fptr);
     fd = fptr->fd;
     for (res = arg->res->ai; res; res = res->ai_next) {
-	if (rsock_connect(fd, res->ai_addr, res->ai_addrlen, 0, NULL) >= 0) {
-	    return Qtrue;
-	}
+        if (rsock_connect(fd, res->ai_addr, res->ai_addrlen, 0, NULL) >= 0) {
+            return Qtrue;
+        }
     }
     return Qfalse;
 }
@@ -92,7 +92,7 @@ udp_connect(VALUE sock, VALUE host, VALUE port)
     GetOpenFile(sock, arg.fptr);
     arg.res = rsock_addrinfo(host, port, rsock_fd_family(arg.fptr->fd), SOCK_DGRAM, 0);
     ret = rb_ensure(udp_connect_internal, (VALUE)&arg,
-		    rsock_freeaddrinfo, (VALUE)arg.res);
+                    rsock_freeaddrinfo, (VALUE)arg.res);
     if (!ret) rsock_sys_fail_host_port("connect(2)", host, port);
     return INT2FIX(0);
 }
@@ -108,10 +108,10 @@ udp_bind_internal(VALUE v)
     rb_io_check_closed(fptr = arg->fptr);
     fd = fptr->fd;
     for (res = arg->res->ai; res; res = res->ai_next) {
-	if (bind(fd, res->ai_addr, res->ai_addrlen) < 0) {
-	    continue;
-	}
-	return Qtrue;
+        if (bind(fd, res->ai_addr, res->ai_addrlen) < 0) {
+            continue;
+        }
+        return Qtrue;
     }
     return Qfalse;
 }
@@ -137,7 +137,7 @@ udp_bind(VALUE sock, VALUE host, VALUE port)
     GetOpenFile(sock, arg.fptr);
     arg.res = rsock_addrinfo(host, port, rsock_fd_family(arg.fptr->fd), SOCK_DGRAM, 0);
     ret = rb_ensure(udp_bind_internal, (VALUE)&arg,
-		    rsock_freeaddrinfo, (VALUE)arg.res);
+                    rsock_freeaddrinfo, (VALUE)arg.res);
     if (!ret) rsock_sys_fail_host_port("bind(2)", host, port);
     return INT2FIX(0);
 }
@@ -170,7 +170,7 @@ udp_send_internal(VALUE v)
 
         if (n >= 0) return RB_SSIZE2NUM(n);
 
-        if (rb_io_maybe_wait_writable(errno, fptr->self, Qnil)) {
+        if (rb_io_maybe_wait_writable(errno, fptr->self, RUBY_IO_TIMEOUT_DEFAULT)) {
             goto retry;
         }
     }
@@ -207,7 +207,7 @@ udp_send(int argc, VALUE *argv, VALUE sock)
     VALUE ret;
 
     if (argc == 2 || argc == 3) {
-	return rsock_bsock_send(argc, argv, sock);
+        return rsock_bsock_send(argc, argv, sock);
     }
     rb_scan_args(argc, argv, "4", &arg.sarg.mesg, &flags, &host, &port);
 
@@ -217,7 +217,7 @@ udp_send(int argc, VALUE *argv, VALUE sock)
     arg.sarg.flags = NUM2INT(flags);
     arg.res = rsock_addrinfo(host, port, rsock_fd_family(arg.fptr->fd), SOCK_DGRAM, 0);
     ret = rb_ensure(udp_send_internal, (VALUE)&arg,
-		    rsock_freeaddrinfo, (VALUE)arg.res);
+                    rsock_freeaddrinfo, (VALUE)arg.res);
     if (!ret) rsock_sys_fail_host_port("sendto(2)", host, port);
     return ret;
 }
@@ -246,5 +246,5 @@ rsock_init_udpsocket(void)
 
     /* for ext/socket/lib/socket.rb use only: */
     rb_define_private_method(rb_cUDPSocket,
-			     "__recvfrom_nonblock", udp_recvfrom_nonblock, 4);
+                             "__recvfrom_nonblock", udp_recvfrom_nonblock, 4);
 }
diff --git a/ext/socket/unixserver.c b/ext/socket/unixserver.c
index 890f9d3fae..0ea5ac083c 100644
--- a/ext/socket/unixserver.c
+++ b/ext/socket/unixserver.c
@@ -10,7 +10,7 @@
 
 #include "rubysocket.h"
 
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
 /*
  * call-seq:
  *   UNIXServer.new(path) => unixserver
@@ -66,7 +66,7 @@ unix_accept_nonblock(VALUE sock, VALUE ex)
     GetOpenFile(sock, fptr);
     fromlen = (socklen_t)sizeof(from);
     return rsock_s_accept_nonblock(rb_cUNIXSocket, ex, fptr,
-			           (struct sockaddr *)&from, &fromlen);
+                                   (struct sockaddr *)&from, &fromlen);
 }
 
 /*
@@ -101,7 +101,7 @@ unix_sysaccept(VALUE server)
 void
 rsock_init_unixserver(void)
 {
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
     /*
      * Document-class: UNIXServer < UNIXSocket
      *
@@ -113,7 +113,7 @@ rsock_init_unixserver(void)
     rb_define_method(rb_cUNIXServer, "accept", unix_accept, 0);
 
     rb_define_private_method(rb_cUNIXServer,
-			     "__accept_nonblock", unix_accept_nonblock, 1);
+                             "__accept_nonblock", unix_accept_nonblock, 1);
 
     rb_define_method(rb_cUNIXServer, "sysaccept", unix_sysaccept, 0);
     rb_define_method(rb_cUNIXServer, "listen", rsock_sock_listen, 1); /* in socket.c */
diff --git a/ext/socket/unixsocket.c b/ext/socket/unixsocket.c
index 857cfa6002..26ab76fc9f 100644
--- a/ext/socket/unixsocket.c
+++ b/ext/socket/unixsocket.c
@@ -10,7 +10,7 @@
 
 #include "rubysocket.h"
 
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
 struct unixsock_arg {
     struct sockaddr_un *sockaddr;
     socklen_t sockaddrlen;
@@ -22,7 +22,7 @@ unixsock_connect_internal(VALUE a)
 {
     struct unixsock_arg *arg = (struct unixsock_arg *)a;
     return (VALUE)rsock_connect(arg->fd, (struct sockaddr*)arg->sockaddr,
-			        arg->sockaddrlen, 0, NULL);
+                                arg->sockaddrlen, 0, NULL);
 }
 
 static VALUE
@@ -43,6 +43,10 @@ unixsock_path_value(VALUE path)
         }
     }
 #endif
+#ifdef _WIN32
+    /* UNIXSocket requires UTF-8 per spec. */
+    path = rb_str_export_to_enc(path, rb_utf8_encoding());
+#endif
     return rb_get_path(path);
 }
 
@@ -66,42 +70,42 @@ rsock_init_unixsock(VALUE sock, VALUE path, int server)
 
     fd = rsock_socket(AF_UNIX, SOCK_STREAM, 0);
     if (fd < 0) {
-	rsock_sys_fail_path("socket(2)", path);
+        rsock_sys_fail_path("socket(2)", path);
     }
 
     if (server) {
         status = bind(fd, (struct sockaddr*)&sockaddr, sockaddrlen);
     }
     else {
-	int prot;
-	struct unixsock_arg arg;
-	arg.sockaddr = &sockaddr;
-	arg.sockaddrlen = sockaddrlen;
-	arg.fd = fd;
+        int prot;
+        struct unixsock_arg arg;
+        arg.sockaddr = &sockaddr;
+        arg.sockaddrlen = sockaddrlen;
+        arg.fd = fd;
         status = (int)rb_protect(unixsock_connect_internal, (VALUE)&arg, &prot);
-	if (prot) {
-	    close(fd);
-	    rb_jump_tag(prot);
-	}
+        if (prot) {
+            close(fd);
+            rb_jump_tag(prot);
+        }
     }
 
     if (status < 0) {
-	int e = errno;
-	close(fd);
-	rsock_syserr_fail_path(e, "connect(2)", path);
+        int e = errno;
+        close(fd);
+        rsock_syserr_fail_path(e, "connect(2)", path);
     }
 
     if (server) {
-	if (listen(fd, SOMAXCONN) < 0) {
-	    int e = errno;
-	    close(fd);
-	    rsock_syserr_fail_path(e, "listen(2)", path);
-	}
+        if (listen(fd, SOMAXCONN) < 0) {
+            int e = errno;
+            close(fd);
+            rsock_syserr_fail_path(e, "listen(2)", path);
+        }
     }
 
     rsock_init_sock(sock, fd);
     if (server) {
-	GetOpenFile(sock, fptr);
+        GetOpenFile(sock, fptr);
         fptr->pathv = rb_str_new_frozen(path);
     }
 
@@ -143,13 +147,13 @@ unix_path(VALUE sock)
 
     GetOpenFile(sock, fptr);
     if (NIL_P(fptr->pathv)) {
-	struct sockaddr_un addr;
-	socklen_t len = (socklen_t)sizeof(addr);
-	socklen_t len0 = len;
-	if (getsockname(fptr->fd, (struct sockaddr*)&addr, &len) < 0)
+        struct sockaddr_un addr;
+        socklen_t len = (socklen_t)sizeof(addr);
+        socklen_t len0 = len;
+        if (getsockname(fptr->fd, (struct sockaddr*)&addr, &len) < 0)
             rsock_sys_fail_path("getsockname(2)", fptr->pathv);
         if (len0 < len) len = len0;
-	fptr->pathv = rb_obj_freeze(rsock_unixpath_str(&addr, len));
+        fptr->pathv = rb_obj_freeze(rsock_unixpath_str(&addr, len));
     }
     return rb_str_dup(fptr->pathv);
 }
@@ -240,21 +244,21 @@ unix_send_io(VALUE sock, VALUE val)
 
 #if FD_PASSING_BY_MSG_CONTROL
     union {
-	struct cmsghdr hdr;
-	char pad[sizeof(struct cmsghdr)+8+sizeof(int)+8];
+        struct cmsghdr hdr;
+        char pad[sizeof(struct cmsghdr)+8+sizeof(int)+8];
     } cmsg;
 #endif
 
     if (rb_obj_is_kind_of(val, rb_cIO)) {
         rb_io_t *valfptr;
-	GetOpenFile(val, valfptr);
-	fd = valfptr->fd;
+        GetOpenFile(val, valfptr);
+        fd = valfptr->fd;
     }
     else if (FIXNUM_P(val)) {
         fd = FIX2INT(val);
     }
     else {
-	rb_raise(rb_eTypeError, "neither IO nor file descriptor");
+        rb_raise(rb_eTypeError, "neither IO nor file descriptor");
     }
 
     GetOpenFile(sock, fptr);
@@ -285,8 +289,8 @@ unix_send_io(VALUE sock, VALUE val)
 
     arg.fd = fptr->fd;
     while ((int)BLOCKING_REGION_FD(sendmsg_blocking, &arg) == -1) {
-	if (!rb_io_wait_writable(arg.fd))
-	    rsock_sys_fail_path("sendmsg(2)", fptr->pathv);
+        if (!rb_io_wait_writable(arg.fd))
+            rsock_sys_fail_path("sendmsg(2)", fptr->pathv);
     }
 
     return Qnil;
@@ -348,16 +352,16 @@ unix_recv_io(int argc, VALUE *argv, VALUE sock)
     int fd;
 #if FD_PASSING_BY_MSG_CONTROL
     union {
-	struct cmsghdr hdr;
-	char pad[sizeof(struct cmsghdr)+8+sizeof(int)+8];
+        struct cmsghdr hdr;
+        char pad[sizeof(struct cmsghdr)+8+sizeof(int)+8];
     } cmsg;
 #endif
 
     rb_scan_args(argc, argv, "02", &klass, &mode);
     if (argc == 0)
-	klass = rb_cIO;
+        klass = rb_cIO;
     if (argc <= 1)
-	mode = Qnil;
+        mode = Qnil;
 
 retry:
     GetOpenFile(sock, fptr);
@@ -400,8 +404,8 @@ retry:
             rb_gc_for_fd(e);
             goto retry;
         }
-	if (!rb_io_wait_readable(arg.fd))
-	    rsock_syserr_fail_path(e, "recvmsg(2)", fptr->pathv);
+        if (!rb_io_wait_readable(arg.fd))
+            rsock_syserr_fail_path(e, "recvmsg(2)", fptr->pathv);
     }
 
 #if FD_PASSING_BY_MSG_CONTROL
@@ -412,41 +416,41 @@ retry:
             rb_gc_for_fd(EMFILE);
             goto retry;
         }
-	rb_raise(rb_eSocket,
-		 "file descriptor was not passed (msg_controllen=%d smaller than sizeof(struct cmsghdr)=%d)",
-		 (int)arg.msg.msg_controllen, (int)sizeof(struct cmsghdr));
+        rb_raise(rb_eSocket,
+                 "file descriptor was not passed (msg_controllen=%d smaller than sizeof(struct cmsghdr)=%d)",
+                 (int)arg.msg.msg_controllen, (int)sizeof(struct cmsghdr));
     }
     if (cmsg.hdr.cmsg_level != SOL_SOCKET) {
-	rb_raise(rb_eSocket,
-		 "file descriptor was not passed (cmsg_level=%d, %d expected)",
-		 cmsg.hdr.cmsg_level, SOL_SOCKET);
+        rb_raise(rb_eSocket,
+                 "file descriptor was not passed (cmsg_level=%d, %d expected)",
+                 cmsg.hdr.cmsg_level, SOL_SOCKET);
     }
     if (cmsg.hdr.cmsg_type != SCM_RIGHTS) {
-	rb_raise(rb_eSocket,
-		 "file descriptor was not passed (cmsg_type=%d, %d expected)",
-		 cmsg.hdr.cmsg_type, SCM_RIGHTS);
+        rb_raise(rb_eSocket,
+                 "file descriptor was not passed (cmsg_type=%d, %d expected)",
+                 cmsg.hdr.cmsg_type, SCM_RIGHTS);
     }
     if (arg.msg.msg_controllen < (socklen_t)CMSG_LEN(sizeof(int))) {
-	rb_raise(rb_eSocket,
-		 "file descriptor was not passed (msg_controllen=%d smaller than CMSG_LEN(sizeof(int))=%d)",
-		 (int)arg.msg.msg_controllen, (int)CMSG_LEN(sizeof(int)));
+        rb_raise(rb_eSocket,
+                 "file descriptor was not passed (msg_controllen=%d smaller than CMSG_LEN(sizeof(int))=%d)",
+                 (int)arg.msg.msg_controllen, (int)CMSG_LEN(sizeof(int)));
     }
     if ((socklen_t)CMSG_SPACE(sizeof(int)) < arg.msg.msg_controllen) {
-	rb_raise(rb_eSocket,
-		 "file descriptor was not passed (msg_controllen=%d bigger than CMSG_SPACE(sizeof(int))=%d)",
-		 (int)arg.msg.msg_controllen, (int)CMSG_SPACE(sizeof(int)));
+        rb_raise(rb_eSocket,
+                 "file descriptor was not passed (msg_controllen=%d bigger than CMSG_SPACE(sizeof(int))=%d)",
+                 (int)arg.msg.msg_controllen, (int)CMSG_SPACE(sizeof(int)));
     }
     if (cmsg.hdr.cmsg_len != CMSG_LEN(sizeof(int))) {
-	rsock_discard_cmsg_resource(&arg.msg, 0);
-	rb_raise(rb_eSocket,
-		 "file descriptor was not passed (cmsg_len=%d, %d expected)",
-		 (int)cmsg.hdr.cmsg_len, (int)CMSG_LEN(sizeof(int)));
+        rsock_discard_cmsg_resource(&arg.msg, 0);
+        rb_raise(rb_eSocket,
+                 "file descriptor was not passed (cmsg_len=%d, %d expected)",
+                 (int)cmsg.hdr.cmsg_len, (int)CMSG_LEN(sizeof(int)));
     }
 #else
     if (arg.msg.msg_accrightslen != sizeof(fd)) {
-	rb_raise(rb_eSocket,
-		 "file descriptor was not passed (accrightslen=%d, %d expected)",
-		 arg.msg.msg_accrightslen, (int)sizeof(fd));
+        rb_raise(rb_eSocket,
+                 "file descriptor was not passed (accrightslen=%d, %d expected)",
+                 arg.msg.msg_accrightslen, (int)sizeof(fd));
     }
 #endif
 
@@ -458,15 +462,15 @@ retry:
     rb_maygvl_fd_fix_cloexec(fd);
 
     if (klass == Qnil)
-	return INT2FIX(fd);
+        return INT2FIX(fd);
     else {
-	ID for_fd;
-	int ff_argc;
-	VALUE ff_argv[2];
-	CONST_ID(for_fd, "for_fd");
-	ff_argc = mode == Qnil ? 1 : 2;
-	ff_argv[0] = INT2FIX(fd);
-	ff_argv[1] = mode;
+        ID for_fd;
+        int ff_argc;
+        VALUE ff_argv[2];
+        CONST_ID(for_fd, "for_fd");
+        ff_argc = mode == Qnil ? 1 : 2;
+        ff_argv[0] = INT2FIX(fd);
+        ff_argv[1] = mode;
         return rb_funcallv(klass, for_fd, ff_argc, ff_argv);
     }
 }
@@ -556,9 +560,9 @@ unix_s_socketpair(int argc, VALUE *argv, VALUE klass)
     domain = INT2FIX(PF_UNIX);
     rb_scan_args(argc, argv, "02", &type, &protocol);
     if (argc == 0)
-	type = INT2FIX(SOCK_STREAM);
+        type = INT2FIX(SOCK_STREAM);
     if (argc <= 1)
-	protocol = INT2FIX(0);
+        protocol = INT2FIX(0);
 
     args[0] = domain;
     args[1] = type;
@@ -571,7 +575,7 @@ unix_s_socketpair(int argc, VALUE *argv, VALUE klass)
 void
 rsock_init_unixsocket(void)
 {
-#ifdef HAVE_SYS_UN_H
+#ifdef HAVE_TYPE_STRUCT_SOCKADDR_UN
     /*
      * Document-class: UNIXSocket < BasicSocket
      *
diff --git a/ext/stringio/stringio.c b/ext/stringio/stringio.c
index 8df07e80f6..0054766dac 100644
--- a/ext/stringio/stringio.c
+++ b/ext/stringio/stringio.c
@@ -12,7 +12,7 @@
 
 **********************************************************************/
 
-#define STRINGIO_VERSION "3.0.1"
+#define STRINGIO_VERSION "3.0.4"
 
 #include "ruby.h"
 #include "ruby/io.h"
@@ -67,15 +67,20 @@ strio_extract_modeenc(VALUE *vmode_p, VALUE *vperm_p, VALUE opthash,
 	    e = strchr(++n, ':');
 	    len = e ? e - n : (long)strlen(n);
 	    if (len > 0 && len <= ENCODING_MAXNAMELEN) {
+		rb_encoding *enc;
 		if (e) {
 		    memcpy(encname, n, len);
 		    encname[len] = '\0';
 		    n = encname;
 		}
-		convconfig_p->enc = rb_enc_find(n);
+		enc = rb_enc_find(n);
+		if (e)
+		    convconfig_p->enc2 = enc;
+		else
+		    convconfig_p->enc = enc;
 	    }
 	    if (e && (len = strlen(++e)) > 0 && len <= ENCODING_MAXNAMELEN) {
-		convconfig_p->enc2 = rb_enc_find(e);
+		convconfig_p->enc = rb_enc_find(e);
 	    }
 	}
     }
@@ -252,9 +257,20 @@ strio_s_allocate(VALUE klass)
 }
 
 /*
- * call-seq: StringIO.new(string=""[, mode])
+ * call-seq:
+ *   StringIO.new(string = '', mode = 'r+') -> new_stringio
+ *
+ * Note that +mode+ defaults to <tt>'r'</tt> if +string+ is frozen.
+ *
+ * Returns a new \StringIO instance formed from +string+ and +mode+;
+ * see {Access Modes}[rdoc-ref:File@Access+Modes]:
  *
- * Creates new StringIO instance from with _string_ and _mode_.
+ *   strio = StringIO.new # => #<StringIO>
+ *   strio.close
+ *
+ * The instance should be closed when no longer needed.
+ *
+ * Related: StringIO.open (accepts block; closes automatically).
  */
 static VALUE
 strio_initialize(int argc, VALUE *argv, VALUE self)
@@ -387,11 +403,26 @@ strio_finalize(VALUE self)
 }
 
 /*
- * call-seq: StringIO.open(string=""[, mode]) {|strio| ...}
+ * call-seq:
+ *   StringIO.open(string = '', mode = 'r+') {|strio| ... }
+ *
+ * Note that +mode+ defaults to <tt>'r'</tt> if +string+ is frozen.
+ *
+ * Creates a new \StringIO instance formed from +string+ and +mode+;
+ * see {Access Modes}[rdoc-ref:File@Access+Modes].
+ *
+ * With no block, returns the new instance:
+ *
+ *   strio = StringIO.open # => #<StringIO>
+ *
+ * With a block, calls the block with the new instance
+ * and returns the block's value;
+ * closes the instance on block exit.
  *
- * Equivalent to StringIO.new except that when it is called with a block, it
- * yields with the new instance and closes it, and returns the result which
- * returned from the block.
+ *   StringIO.open {|strio| p strio }
+ *   # => #<StringIO>
+ *
+ * Related: StringIO.new.
  */
 static VALUE
 strio_s_open(int argc, VALUE *argv, VALUE klass)
@@ -477,9 +508,23 @@ strio_unimpl(int argc, VALUE *argv, VALUE self)
 }
 
 /*
- * call-seq: strio.string     -> string
+ * call-seq:
+ *   string -> string
+ *
+ * Returns underlying string:
+ *
+ *   StringIO.open('foo') do |strio|
+ *     p strio.string
+ *     strio.string = 'bar'
+ *     p strio.string
+ *   end
+ *
+ * Output:
+ *
+ *   "foo"
+ *   "bar"
  *
- * Returns underlying String object, the subject of IO.
+ * Related: StringIO#string= (assigns the underlying string).
  */
 static VALUE
 strio_get_string(VALUE self)
@@ -489,9 +534,23 @@ strio_get_string(VALUE self)
 
 /*
  * call-seq:
- *   strio.string = string  -> string
+ *   string = other_string -> other_string
  *
- * Changes underlying String object, the subject of IO.
+ * Assigns the underlying string as +other_string+, and sets position to zero;
+ * returns +other_string+:
+ *
+ *   StringIO.open('foo') do |strio|
+ *     p strio.string
+ *     strio.string = 'bar'
+ *     p strio.string
+ *   end
+ *
+ * Output:
+ *
+ *   "foo"
+ *   "bar"
+ *
+ * Related: StringIO#string (returns the underlying string).
  */
 static VALUE
 strio_set_string(VALUE self, VALUE string)
@@ -509,10 +568,13 @@ strio_set_string(VALUE self, VALUE string)
 
 /*
  * call-seq:
- *   strio.close  -> nil
+ *   close -> nil
+ *
+ * Closes +self+ for both reading and writing.
  *
- * Closes a StringIO. The stream is unavailable for any further data
- * operations; an +IOError+ is raised if such an attempt is made.
+ * Raises IOError if reading or writing is attempted.
+ *
+ * Related: StringIO#close_read, StringIO#close_write.
  */
 static VALUE
 strio_close(VALUE self)
@@ -524,10 +586,13 @@ strio_close(VALUE self)
 
 /*
  * call-seq:
- *   strio.close_read    -> nil
+ *   close_read -> nil
+ *
+ * Closes +self+ for reading; closed-write setting remains unchanged.
+ *
+ * Raises IOError if reading is attempted.
  *
- * Closes the read end of a StringIO.  Will raise an +IOError+ if the
- * receiver is not readable.
+ * Related: StringIO#close, StringIO#close_write.
  */
 static VALUE
 strio_close_read(VALUE self)
@@ -542,10 +607,13 @@ strio_close_read(VALUE self)
 
 /*
  * call-seq:
- *   strio.close_write    -> nil
+ *   close_write -> nil
  *
- * Closes the write end of a StringIO.  Will raise an  +IOError+ if the
- * receiver is not writeable.
+ * Closes +self+ for writing; closed-read setting remains unchanged.
+ *
+ * Raises IOError if writing is attempted.
+ *
+ * Related: StringIO#close, StringIO#close_read.
  */
 static VALUE
 strio_close_write(VALUE self)
@@ -560,9 +628,10 @@ strio_close_write(VALUE self)
 
 /*
  * call-seq:
- *   strio.closed?    -> true or false
+ *   closed? -> true or false
  *
- * Returns +true+ if the stream is completely closed, +false+ otherwise.
+ * Returns +true+ if +self+ is closed for both reading and writing,
+ * +false+ otherwise.
  */
 static VALUE
 strio_closed(VALUE self)
@@ -574,9 +643,9 @@ strio_closed(VALUE self)
 
 /*
  * call-seq:
- *   strio.closed_read?    -> true or false
+ *   closed_read? -> true or false
  *
- * Returns +true+ if the stream is not readable, +false+ otherwise.
+ * Returns +true+ if +self+ is closed for reading, +false+ otherwise.
  */
 static VALUE
 strio_closed_read(VALUE self)
@@ -588,9 +657,9 @@ strio_closed_read(VALUE self)
 
 /*
  * call-seq:
- *   strio.closed_write?    -> true or false
+ *   closed_write? -> true or false
  *
- * Returns +true+ if the stream is not writable, +false+ otherwise.
+ * Returns +true+ if +self+ is closed for writing, +false+ otherwise.
  */
 static VALUE
 strio_closed_write(VALUE self)
@@ -610,11 +679,14 @@ strio_to_read(VALUE self)
 
 /*
  * call-seq:
- *   strio.eof     -> true or false
- *   strio.eof?    -> true or false
+ *   eof? -> true or false
+ *
+ * Returns +true+ if positioned at end-of-stream, +false+ otherwise;
+ * see {Position}[rdoc-ref:File@Position].
  *
- * Returns true if the stream is at the end of the data (underlying string).
- * The stream must be opened for reading or an +IOError+ will be raised.
+ * Raises IOError if the stream is not opened for reading.
+ *
+ * StreamIO#eof is an alias for StreamIO#eof?.
  */
 static VALUE
 strio_eof(VALUE self)
@@ -644,13 +716,10 @@ strio_copy(VALUE copy, VALUE orig)
 
 /*
  * call-seq:
- *   strio.lineno    -> integer
+ *   lineno -> current_line_number
  *
- * Returns the current line number. The stream must be
- * opened for reading. +lineno+ counts the number of times  +gets+ is
- * called, rather than the number of newlines  encountered. The two
- * values will differ if +gets+ is  called with a separator other than
- * newline.  See also the  <code>$.</code> variable.
+ * Returns the current line number in +self+;
+ * see {Line Number}[rdoc-ref:IO@Line+Number].
  */
 static VALUE
 strio_get_lineno(VALUE self)
@@ -660,10 +729,10 @@ strio_get_lineno(VALUE self)
 
 /*
  * call-seq:
- *   strio.lineno = integer    -> integer
+ *   lineno = new_line_number -> new_line_number
  *
- * Manually sets the current line number to the given value.
- * <code>$.</code> is updated only on the next read.
+ * Sets the current line number in +self+ to the given +new_line_number+;
+ * see {Line Number}[rdoc-ref:IO@Line+Number].
  */
 static VALUE
 strio_set_lineno(VALUE self, VALUE lineno)
@@ -674,9 +743,10 @@ strio_set_lineno(VALUE self, VALUE lineno)
 
 /*
  * call-seq:
- *   strio.binmode    -> stringio
+ *   binmode -> self
  *
- * Puts stream into binary mode. See IO#binmode.
+ * Sets the data mode in +self+ to binary mode;
+ * see {Data Mode}[rdoc-ref:File@Data+Mode].
  *
  */
 static VALUE
@@ -700,11 +770,27 @@ strio_binmode(VALUE self)
 
 /*
  * call-seq:
- *   strio.reopen(other_StrIO)     -> strio
- *   strio.reopen(string, mode)    -> strio
+ *   reopen(other, mode = 'r+') -> self
+ *
+ * Reinitializes the stream with the given +other+ (string or StringIO) and +mode+;
+ * see IO.new:
+ *
+ *   StringIO.open('foo') do |strio|
+ *     p strio.string
+ *     strio.reopen('bar')
+ *     p strio.string
+ *     other_strio = StringIO.new('baz')
+ *     strio.reopen(other_strio)
+ *     p strio.string
+ *     other_strio.close
+ *   end
+ *
+ * Output:
+ *
+ *   "foo"
+ *   "bar"
+ *   "baz"
  *
- * Reinitializes the stream with the given <i>other_StrIO</i> or _string_
- * and _mode_ (see StringIO#new).
  */
 static VALUE
 strio_reopen(int argc, VALUE *argv, VALUE self)
@@ -718,10 +804,12 @@ strio_reopen(int argc, VALUE *argv, VALUE self)
 
 /*
  * call-seq:
- *   strio.pos     -> integer
- *   strio.tell    -> integer
+ *   pos -> stream_position
  *
- * Returns the current offset (in bytes).
+ * Returns the current position (in bytes);
+ * see {Position}[rdoc-ref:IO@Position].
+ *
+ * StringIO#tell is an alias for StringIO#pos.
  */
 static VALUE
 strio_get_pos(VALUE self)
@@ -731,9 +819,10 @@ strio_get_pos(VALUE self)
 
 /*
  * call-seq:
- *   strio.pos = integer    -> integer
+ *   pos = new_position -> new_position
  *
- * Seeks to the given position (in bytes).
+ * Sets the current position (in bytes);
+ * see {Position}[rdoc-ref:IO@Position].
  */
 static VALUE
 strio_set_pos(VALUE self, VALUE pos)
@@ -749,10 +838,11 @@ strio_set_pos(VALUE self, VALUE pos)
 
 /*
  * call-seq:
- *   strio.rewind    -> 0
+ *   rewind -> 0
  *
- * Positions the stream to the beginning of input, resetting
- * +lineno+ to zero.
+ * Sets the current position and line number to zero;
+ * see {Position}[rdoc-ref:IO@Position]
+ * and {Line Number}[rdoc-ref:IO@Line+Number].
  */
 static VALUE
 strio_rewind(VALUE self)
@@ -765,10 +855,11 @@ strio_rewind(VALUE self)
 
 /*
  * call-seq:
- *   strio.seek(amount, whence=SEEK_SET) -> 0
+ *   seek(offset, whence = SEEK_SET) -> 0
  *
- * Seeks to a given offset _amount_ in the stream according to
- * the value of _whence_ (see IO#seek).
+ * Sets the current position to the given integer +offset+ (in bytes),
+ * with respect to a given constant +whence+;
+ * see {Position}[rdoc-ref:IO@Position].
  */
 static VALUE
 strio_seek(int argc, VALUE *argv, VALUE self)
@@ -804,9 +895,9 @@ strio_seek(int argc, VALUE *argv, VALUE self)
 
 /*
  * call-seq:
- *   strio.sync    -> true
+ *   sync -> true
  *
- * Returns +true+ always.
+ * Returns +true+; implemented only for compatibility with other stream classes.
  */
 static VALUE
 strio_get_sync(VALUE self)
@@ -821,10 +912,12 @@ strio_get_sync(VALUE self)
 
 /*
  * call-seq:
- *   strio.each_byte {|byte| block }  -> strio
- *   strio.each_byte                  -> anEnumerator
+ *   each_byte {|byte| ... } -> self
+ *
+ * With a block given, calls the block with each remaining byte in the stream;
+ * see {Byte IO}[rdoc-ref:IO@Byte+IO].
  *
- * See IO#each_byte.
+ * With no block given, returns an enumerator.
  */
 static VALUE
 strio_each_byte(VALUE self)
@@ -842,9 +935,10 @@ strio_each_byte(VALUE self)
 
 /*
  * call-seq:
- *   strio.getc   -> string or nil
+ *   getc -> character or nil
  *
- * See IO#getc.
+ * Reads and returns the next character from the stream;
+ * see {Character IO}[rdoc-ref:IO@Character+IO].
  */
 static VALUE
 strio_getc(VALUE self)
@@ -867,9 +961,10 @@ strio_getc(VALUE self)
 
 /*
  * call-seq:
- *   strio.getbyte   -> fixnum or nil
+ *   getbyte -> byte or nil
  *
- * See IO#getbyte.
+ * Reads and returns the next 8-bit byte from the stream;
+ * see {Byte IO}[rdoc-ref:IO@Byte+IO].
  */
 static VALUE
 strio_getbyte(VALUE self)
@@ -905,12 +1000,10 @@ strio_extend(struct StringIO *ptr, long pos, long len)
 
 /*
  * call-seq:
- *   strio.ungetc(string)   -> nil
+ *   ungetc(character) -> nil
  *
- * Pushes back one character (passed as a parameter)
- * such that a subsequent buffered read will return it.  There is no
- * limitation for multiple pushbacks including pushing back behind the
- * beginning of the buffer string.
+ * Pushes back ("unshifts") a character or integer onto the stream;
+ * see {Character IO}[rdoc-ref:IO@Character+IO].
  */
 static VALUE
 strio_ungetc(VALUE self, VALUE c)
@@ -945,9 +1038,10 @@ strio_ungetc(VALUE self, VALUE c)
 
 /*
  * call-seq:
- *   strio.ungetbyte(fixnum)   -> nil
+ *   ungetbyte(byte) -> nil
  *
- * See IO#ungetbyte
+ * Pushes back ("unshifts") an 8-bit byte onto the stream;
+ * see {Byte IO}[rdoc-ref:IO@Byte+IO].
  */
 static VALUE
 strio_ungetbyte(VALUE self, VALUE c)
@@ -984,7 +1078,7 @@ strio_unget_bytes(struct StringIO *ptr, const char *cp, long cl)
     len = RSTRING_LEN(str);
     rest = pos - len;
     if (cl > pos) {
-	long ex = (rest < 0 ? cl-pos : cl+rest);
+	long ex = cl - (rest < 0 ? pos : len);
 	rb_str_modify_expand(str, ex);
 	rb_str_set_len(str, len + ex);
 	s = RSTRING_PTR(str);
@@ -1007,9 +1101,10 @@ strio_unget_bytes(struct StringIO *ptr, const char *cp, long cl)
 
 /*
  * call-seq:
- *   strio.readchar   -> string
+ *   readchar -> string
  *
- * See IO#readchar.
+ * Like +getc+, but raises an exception if already at end-of-stream;
+ * see {Character IO}[rdoc-ref:IO@Character+IO].
  */
 static VALUE
 strio_readchar(VALUE self)
@@ -1021,9 +1116,10 @@ strio_readchar(VALUE self)
 
 /*
  * call-seq:
- *   strio.readbyte   -> fixnum
+ *   readbyte -> byte
  *
- * See IO#readbyte.
+ * Like +getbyte+, but raises an exception if already at end-of-stream;
+ * see {Byte IO}[rdoc-ref:IO@Byte+IO].
  */
 static VALUE
 strio_readbyte(VALUE self)
@@ -1035,10 +1131,12 @@ strio_readbyte(VALUE self)
 
 /*
  * call-seq:
- *   strio.each_char {|char| block }  -> strio
- *   strio.each_char                  -> anEnumerator
+ *   each_char {|c| ... } -> self
+ *
+ * With a block given, calls the block with each remaining character in the stream;
+ * see {Character IO}[rdoc-ref:IO@Character+IO].
  *
- * See IO#each_char.
+ * With no block given, returns an enumerator.
  */
 static VALUE
 strio_each_char(VALUE self)
@@ -1055,10 +1153,12 @@ strio_each_char(VALUE self)
 
 /*
  * call-seq:
- *   strio.each_codepoint {|c| block }  -> strio
- *   strio.each_codepoint               -> anEnumerator
+ *   each_codepoint {|codepoint| ... } -> self
  *
- * See IO#each_codepoint.
+ * With a block given, calls the block with each remaining codepoint in the stream;
+ * see {Codepoint IO}[rdoc-ref:IO@Codepoint+IO].
+ *
+ * With no block given, returns an enumerator.
  */
 static VALUE
 strio_each_codepoint(VALUE self)
@@ -1125,8 +1225,10 @@ prepare_getline_args(struct getline_arg *arg, int argc, VALUE *argv)
 {
     VALUE str, lim, opts;
     long limit = -1;
+    int respect_chomp;
 
     argc = rb_scan_args(argc, argv, "02:", &str, &lim, &opts);
+    respect_chomp = argc == 0 || !NIL_P(str);
     switch (argc) {
       case 0:
 	str = rb_rs;
@@ -1160,7 +1262,9 @@ prepare_getline_args(struct getline_arg *arg, int argc, VALUE *argv)
 	    keywords[0] = rb_intern_const("chomp");
 	}
 	rb_get_kwargs(opts, keywords, 0, 1, &vchomp);
-	arg->chomp = (vchomp != Qundef) && RTEST(vchomp);
+        if (respect_chomp) {
+	    arg->chomp = (vchomp != Qundef) && RTEST(vchomp);
+        }
     }
     return arg;
 }
@@ -1181,7 +1285,7 @@ strio_getline(struct getline_arg *arg, struct StringIO *ptr)
     const char *s, *e, *p;
     long n, limit = arg->limit;
     VALUE str = arg->rs;
-    int w = 0;
+    long w = 0;
     rb_encoding *enc = get_enc(ptr);
 
     if (ptr->pos >= (n = RSTRING_LEN(ptr->string))) {
@@ -1200,6 +1304,7 @@ strio_getline(struct getline_arg *arg, struct StringIO *ptr)
 	str = strio_substr(ptr, ptr->pos, e - s - w, enc);
     }
     else if ((n = RSTRING_LEN(str)) == 0) {
+        const char *paragraph_end = NULL;
 	p = s;
 	while (p[(p + 1 < e) && (*p == '\r') && 0] == '\n') {
 	    p += *p == '\r';
@@ -1209,19 +1314,21 @@ strio_getline(struct getline_arg *arg, struct StringIO *ptr)
 	}
 	s = p;
 	while ((p = memchr(p, '\n', e - p)) && (p != e)) {
-	    if (*++p == '\n') {
-		e = p + 1;
-		w = (arg->chomp ? 1 : 0);
-		break;
-	    }
-	    else if (*p == '\r' && p < e && p[1] == '\n') {
-		e = p + 2;
-		w = (arg->chomp ? 2 : 0);
-		break;
-	    }
+            p++;
+            if (!((p < e && *p == '\n') ||
+                  (p + 1 < e && *p == '\r' && *(p+1) == '\n'))) {
+                continue;
+            }
+            paragraph_end = p - ((*(p-2) == '\r') ? 2 : 1);
+            while ((p < e && *p == '\n') ||
+                   (p + 1 < e && *p == '\r' && *(p+1) == '\n')) {
+                p += (*p == '\r') ? 2 : 1;
+            }
+            e = p;
+            break;
 	}
-	if (!w && arg->chomp) {
-	    w = chomp_newline_width(s, e);
+	if (arg->chomp && paragraph_end) {
+	    w = e - paragraph_end;
 	}
 	str = strio_substr(ptr, s - RSTRING_PTR(ptr->string), e - s - w, enc);
     }
@@ -1233,11 +1340,13 @@ strio_getline(struct getline_arg *arg, struct StringIO *ptr)
 	str = strio_substr(ptr, ptr->pos, e - s - w, enc);
     }
     else {
-	if (n < e - s) {
-	    if (e - s < 1024) {
+	if (n < e - s + arg->chomp) {
+	    /* unless chomping, RS at the end does not matter */
+	    if (e - s < 1024 || n == e - s) {
 		for (p = s; p + n <= e; ++p) {
 		    if (MEMCMP(p, RSTRING_PTR(str), char, n) == 0) {
-			e = p + (arg->chomp ? 0 : n);
+			e = p + n;
+			w = (arg->chomp ? n : 0);
 			break;
 		    }
 		}
@@ -1260,11 +1369,13 @@ strio_getline(struct getline_arg *arg, struct StringIO *ptr)
 
 /*
  * call-seq:
- *   strio.gets(sep=$/, chomp: false)     -> string or nil
- *   strio.gets(limit, chomp: false)      -> string or nil
- *   strio.gets(sep, limit, chomp: false) -> string or nil
+ *   gets(sep = $/, chomp: false) -> string or nil
+ *   gets(limit, chomp: false) -> string or nil
+ *   gets(sep, limit, chomp: false) -> string or nil
  *
- * See IO#gets.
+ * Reads and returns a line from the stream;
+ * assigns the return value to <tt>$_</tt>;
+ * see {Line IO}[rdoc-ref:IO@Line+IO].
  */
 static VALUE
 strio_gets(int argc, VALUE *argv, VALUE self)
@@ -1284,11 +1395,12 @@ strio_gets(int argc, VALUE *argv, VALUE self)
 
 /*
  * call-seq:
- *   strio.readline(sep=$/, chomp: false)     -> string
- *   strio.readline(limit, chomp: false)      -> string or nil
- *   strio.readline(sep, limit, chomp: false) -> string or nil
+ *   readline(sep = $/, chomp: false) -> string
+ *   readline(limit, chomp: false) -> string
+ *   readline(sep, limit, chomp: false) -> string
  *
- * See IO#readline.
+ * Reads a line as with IO#gets, but raises EOFError if already at end-of-file;
+ * see {Line IO}[rdoc-ref:IO@Line+IO].
  */
 static VALUE
 strio_readline(int argc, VALUE *argv, VALUE self)
@@ -1300,17 +1412,16 @@ strio_readline(int argc, VALUE *argv, VALUE self)
 
 /*
  * call-seq:
- *   strio.each(sep=$/, chomp: false) {|line| block }         -> strio
- *   strio.each(limit, chomp: false) {|line| block }          -> strio
- *   strio.each(sep, limit, chomp: false) {|line| block }     -> strio
- *   strio.each(...)                                          -> anEnumerator
+ *   each_line(sep = $/, chomp: false) {|line| ... }   -> self
+ *   each_line(limit, chomp: false) {|line| ... }      -> self
+ *   each_line(sep, limit, chomp: false) {|line| ... } -> self
  *
- *   strio.each_line(sep=$/, chomp: false) {|line| block }     -> strio
- *   strio.each_line(limit, chomp: false) {|line| block }      -> strio
- *   strio.each_line(sep, limit, chomp: false) {|line| block } -> strio
- *   strio.each_line(...)                                      -> anEnumerator
+ * Calls the block with each remaining line read from the stream;
+ * does nothing if already at end-of-file;
+ * returns +self+.
+ * See {Line IO}[rdoc-ref:IO@Line+IO].
  *
- * See IO#each.
+ * StringIO#each is an alias for StringIO#each_line.
  */
 static VALUE
 strio_each(int argc, VALUE *argv, VALUE self)
@@ -1655,7 +1766,7 @@ strio_truncate(VALUE self, VALUE len)
     if (plen < l) {
 	MEMZERO(RSTRING_PTR(string) + plen, char, l - plen);
     }
-    return len;
+    return INT2FIX(0);
 }
 
 /*
@@ -1711,7 +1822,14 @@ strio_set_encoding(int argc, VALUE *argv, VALUE self)
 	enc = rb_default_external_encoding();
     }
     else {
-	enc = rb_to_encoding(ext_enc);
+	enc = rb_find_encoding(ext_enc);
+	if (!enc) {
+	    struct rb_io_enc_t convconfig;
+	    int oflags, fmode;
+	    VALUE vmode = rb_str_append(rb_str_new_cstr("r:"), ext_enc);
+	    rb_io_extract_modeenc(&vmode, 0, Qnil, &oflags, &fmode, &convconfig);
+	    enc = convconfig.enc2;
+	}
     }
     ptr->enc = enc;
     if (WRITABLE(self)) {
@@ -1731,24 +1849,16 @@ strio_set_encoding_by_bom(VALUE self)
 }
 
 /*
- * Pseudo I/O on String object, with interface corresponding to IO.
+ * \IO streams for strings, with access similar to
+ * {IO}[rdoc-ref:IO];
+ * see {IO}[rdoc-ref:IO].
  *
- * Commonly used to simulate <code>$stdio</code> or <code>$stderr</code>
+ * === About the Examples
  *
- * === Examples
+ * Examples on this page assume that \StringIO has been required:
  *
  *   require 'stringio'
  *
- *   # Writing stream emulation
- *   io = StringIO.new
- *   io.puts "Hello World"
- *   io.string #=> "Hello World\n"
- *
- *   # Reading stream emulation
- *   io = StringIO.new "first\nsecond\nlast\n"
- *   io.getc #=> "f"
- *   io.gets #=> "irst\n"
- *   io.read #=> "second\nlast\n"
  */
 void
 Init_stringio(void)
diff --git a/ext/stringio/stringio.gemspec b/ext/stringio/stringio.gemspec
index 524d976cfb..1015d261f5 100644
--- a/ext/stringio/stringio.gemspec
+++ b/ext/stringio/stringio.gemspec
@@ -1,4 +1,4 @@
-# -*- encoding: utf-8 -*-
+# -*- coding: utf-8 -*-
 # frozen_string_literal: true
 
 source_version = ["", "ext/stringio/"].find do |dir|
@@ -16,11 +16,18 @@ Gem::Specification.new do |s|
 
   s.required_rubygems_version = Gem::Requirement.new(">= 2.6")
   s.require_paths = ["lib"]
-  s.authors = ["Nobu Nakada"]
+  s.authors = ["Nobu Nakada", "Charles Oliver Nutter"]
   s.description = "Pseudo `IO` class from/to `String`."
-  s.email = "nobu@ruby-lang.org"
-  s.extensions = ["ext/stringio/extconf.rb"]
-  s.files = ["README.md", "ext/stringio/extconf.rb", "ext/stringio/stringio.c"]
+  s.email = ["nobu@ruby-lang.org", "headius@headius.com"]
+  s.files = ["README.md"]
+  jruby = true if Gem::Platform.new('java') =~ s.platform or RUBY_ENGINE == 'jruby'
+  if jruby
+    s.files += ["lib/stringio.rb", "lib/stringio.jar"]
+    s.platform = "java"
+  else
+    s.extensions = ["ext/stringio/extconf.rb"]
+    s.files += ["ext/stringio/extconf.rb", "ext/stringio/stringio.c"]
+  end
   s.homepage = "https://github.com/ruby/stringio"
   s.licenses = ["Ruby", "BSD-2-Clause"]
   s.required_ruby_version = ">= 2.5"
diff --git a/ext/strscan/extconf.rb b/ext/strscan/extconf.rb
index f0ecbf85d8..3c311d2364 100644
--- a/ext/strscan/extconf.rb
+++ b/ext/strscan/extconf.rb
@@ -1,5 +1,10 @@
 # frozen_string_literal: true
 require 'mkmf'
-$INCFLAGS << " -I$(top_srcdir)" if $extmk
-have_func("onig_region_memsize", "ruby.h")
-create_makefile 'strscan'
+if RUBY_ENGINE == 'ruby'
+  $INCFLAGS << " -I$(top_srcdir)" if $extmk
+  have_func("onig_region_memsize(NULL)")
+  have_func("rb_reg_onig_match", "ruby/re.h")
+  create_makefile 'strscan'
+else
+  File.write('Makefile', dummy_makefile("").join)
+end
diff --git a/ext/strscan/strscan.c b/ext/strscan/strscan.c
index e1426380b4..16d669d8a5 100644
--- a/ext/strscan/strscan.c
+++ b/ext/strscan/strscan.c
@@ -22,7 +22,7 @@ extern size_t onig_region_memsize(const struct re_registers *regs);
 
 #include <stdbool.h>
 
-#define STRSCAN_VERSION "3.0.1"
+#define STRSCAN_VERSION "3.0.7"
 
 /* =======================================================================
                          Data Type Definitions
@@ -435,11 +435,11 @@ strscan_get_pos(VALUE self)
  *
  * In short, it's a 0-based index into the string.
  *
- *   s = StringScanner.new("abcädeföghi")
- *   s.charpos           # -> 0
- *   s.scan_until(/ä/)   # -> "abcä"
- *   s.pos               # -> 5
- *   s.charpos           # -> 4
+ *   s = StringScanner.new("abc\u00e4def\u00f6ghi")
+ *   s.charpos                # -> 0
+ *   s.scan_until(/\u00e4/)   # -> "abc\u00E4"
+ *   s.pos                    # -> 5
+ *   s.charpos                # -> 4
  */
 static VALUE
 strscan_get_charpos(VALUE self)
@@ -539,6 +539,68 @@ adjust_register_position(struct strscanner *p, long position)
     }
 }
 
+/* rb_reg_onig_match is available in Ruby 3.3 and later. */
+#ifndef HAVE_RB_REG_ONIG_MATCH
+static OnigPosition
+rb_reg_onig_match(VALUE re, VALUE str,
+                  OnigPosition (*match)(regex_t *reg, VALUE str, struct re_registers *regs, void *args),
+                  void *args, struct re_registers *regs)
+{
+    regex_t *reg = rb_reg_prepare_re(re, str);
+
+    bool tmpreg = reg != RREGEXP_PTR(re);
+    if (!tmpreg) RREGEXP(re)->usecnt++;
+
+    OnigPosition result = match(reg, str, regs, args);
+
+    if (!tmpreg) RREGEXP(re)->usecnt--;
+    if (tmpreg) {
+        if (RREGEXP(re)->usecnt) {
+            onig_free(reg);
+        }
+        else {
+            onig_free(RREGEXP_PTR(re));
+            RREGEXP_PTR(re) = reg;
+        }
+    }
+
+    if (result < 0) {
+        if (result != ONIG_MISMATCH) {
+            rb_raise(ScanError, "regexp buffer overflow");
+        }
+    }
+
+    return result;
+}
+#endif
+
+static OnigPosition
+strscan_match(regex_t *reg, VALUE str, struct re_registers *regs, void *args_ptr)
+{
+    struct strscanner *p = (struct strscanner *)args_ptr;
+
+    return onig_match(reg,
+                      match_target(p),
+                      (UChar* )(CURPTR(p) + S_RESTLEN(p)),
+                      (UChar* )CURPTR(p),
+                      regs,
+                      ONIG_OPTION_NONE);
+}
+
+static OnigPosition
+strscan_search(regex_t *reg, VALUE str, struct re_registers *regs, void *args_ptr)
+{
+    struct strscanner *p = (struct strscanner *)args_ptr;
+
+    return onig_search(reg,
+                       match_target(p),
+                       (UChar *)(CURPTR(p) + S_RESTLEN(p)),
+                       (UChar *)CURPTR(p),
+                       (UChar *)(CURPTR(p) + S_RESTLEN(p)),
+                       regs,
+                       ONIG_OPTION_NONE);
+}
+
 static VALUE
 strscan_do_scan(VALUE self, VALUE pattern, int succptr, int getstr, int headonly)
 {
@@ -560,47 +622,14 @@ strscan_do_scan(VALUE self, VALUE pattern, int succptr, int getstr, int headonly
     }
 
     if (RB_TYPE_P(pattern, T_REGEXP)) {
-        regex_t *rb_reg_prepare_re(VALUE re, VALUE str);
-        regex_t *re;
-        long ret;
-        int tmpreg;
-
         p->regex = pattern;
-        re = rb_reg_prepare_re(pattern, p->str);
-        tmpreg = re != RREGEXP_PTR(pattern);
-        if (!tmpreg) RREGEXP(pattern)->usecnt++;
-
-        if (headonly) {
-            ret = onig_match(re,
-                             match_target(p),
-                             (UChar* )(CURPTR(p) + S_RESTLEN(p)),
-                             (UChar* )CURPTR(p),
-                             &(p->regs),
-                             ONIG_OPTION_NONE);
-        }
-        else {
-            ret = onig_search(re,
-                              match_target(p),
-                              (UChar* )(CURPTR(p) + S_RESTLEN(p)),
-                              (UChar* )CURPTR(p),
-                              (UChar* )(CURPTR(p) + S_RESTLEN(p)),
-                              &(p->regs),
-                              ONIG_OPTION_NONE);
-        }
-        if (!tmpreg) RREGEXP(pattern)->usecnt--;
-        if (tmpreg) {
-            if (RREGEXP(pattern)->usecnt) {
-                onig_free(re);
-            }
-            else {
-                onig_free(RREGEXP_PTR(pattern));
-                RREGEXP_PTR(pattern) = re;
-            }
-        }
+        OnigPosition ret = rb_reg_onig_match(pattern,
+                                             p->str,
+                                             headonly ? strscan_match : strscan_search,
+                                             (void *)p,
+                                             &(p->regs));
 
-        if (ret == -2) rb_raise(ScanError, "regexp buffer overflow");
-        if (ret < 0) {
-            /* not matched */
+        if (ret == ONIG_MISMATCH) {
             return Qnil;
         }
     }
@@ -1038,8 +1067,9 @@ strscan_empty_p(VALUE self)
  * This method is obsolete; use #eos? instead.
  *
  *   s = StringScanner.new('test string')
- *   s.eos?              # These two
- *   s.rest?             # are opposites.
+ *   # These two are opposites
+ *   s.eos? # => false
+ *   s.rest? # => true
  */
 static VALUE
 strscan_rest_p(VALUE self)
@@ -1458,6 +1488,56 @@ strscan_fixed_anchor_p(VALUE self)
     return p->fixed_anchor_p ? Qtrue : Qfalse;
 }
 
+typedef struct {
+    VALUE self;
+    VALUE captures;
+} named_captures_data;
+
+static int
+named_captures_iter(const OnigUChar *name,
+                    const OnigUChar *name_end,
+                    int back_num,
+                    int *back_refs,
+                    OnigRegex regex,
+                    void *arg)
+{
+    named_captures_data *data = arg;
+
+    VALUE key = rb_str_new((const char *)name, name_end - name);
+    VALUE value = RUBY_Qnil;
+    int i;
+    for (i = 0; i < back_num; i++) {
+        value = strscan_aref(data->self, INT2NUM(back_refs[i]));
+    }
+    rb_hash_aset(data->captures, key, value);
+    return 0;
+}
+
+/*
+ * call-seq:
+ *   scanner.named_captures -> hash
+ *
+ * Returns a hash of string variables matching the regular expression.
+ *
+ *   scan = StringScanner.new('foobarbaz')
+ *   scan.match?(/(?<f>foo)(?<r>bar)(?<z>baz)/)
+ *   scan.named_captures # -> {"f"=>"foo", "r"=>"bar", "z"=>"baz"}
+ */
+static VALUE
+strscan_named_captures(VALUE self)
+{
+    struct strscanner *p;
+    GET_SCANNER(self, p);
+    named_captures_data data;
+    data.self = self;
+    data.captures = rb_hash_new();
+    if (!RB_NIL_P(p->regex)) {
+        onig_foreach_name(RREGEXP_PTR(p->regex), named_captures_iter, &data);
+    }
+
+    return data.captures;
+}
+
 /* =======================================================================
                               Ruby Interface
    ======================================================================= */
@@ -1468,6 +1548,8 @@ strscan_fixed_anchor_p(VALUE self)
  * StringScanner provides for lexical scanning operations on a String.  Here is
  * an example of its usage:
  *
+ *   require 'strscan'
+ *
  *   s = StringScanner.new('This is an example string')
  *   s.eos?               # -> false
  *
@@ -1650,4 +1732,6 @@ Init_strscan(void)
     rb_define_method(StringScanner, "inspect",     strscan_inspect,     0);
 
     rb_define_method(StringScanner, "fixed_anchor?", strscan_fixed_anchor_p, 0);
+
+    rb_define_method(StringScanner, "named_captures", strscan_named_captures, 0);
 }
diff --git a/ext/strscan/strscan.gemspec b/ext/strscan/strscan.gemspec
index 5d8119ea4c..8a61c7abe6 100644
--- a/ext/strscan/strscan.gemspec
+++ b/ext/strscan/strscan.gemspec
@@ -16,13 +16,26 @@ Gem::Specification.new do |s|
   s.summary = "Provides lexical scanning operations on a String."
   s.description = "Provides lexical scanning operations on a String."
 
-  s.require_path = %w{lib}
-  s.files = %w{ext/strscan/extconf.rb ext/strscan/strscan.c}
-  s.extensions = %w{ext/strscan/extconf.rb}
+  files = [
+    "COPYING",
+    "LICENSE.txt",
+  ]
+  if RUBY_ENGINE == "jruby"
+    s.require_paths = %w{ext/jruby/lib lib}
+    files << "ext/jruby/lib/strscan.rb"
+    files << "lib/strscan.jar"
+    s.platform = "java"
+  else
+    s.require_paths = %w{lib}
+    files << "ext/strscan/extconf.rb"
+    files << "ext/strscan/strscan.c"
+    s.extensions = %w{ext/strscan/extconf.rb}
+  end
+  s.files = files
   s.required_ruby_version = ">= 2.4.0"
 
-  s.authors = ["Minero Aoki", "Sutou Kouhei"]
-  s.email = [nil, "kou@cozmixng.org"]
+  s.authors = ["Minero Aoki", "Sutou Kouhei", "Charles Oliver Nutter"]
+  s.email = [nil, "kou@cozmixng.org", "headius@headius.com"]
   s.homepage = "https://github.com/ruby/strscan"
   s.licenses = ["Ruby", "BSD-2-Clause"]
 end
diff --git a/ext/syslog/syslog.c b/ext/syslog/syslog.c
index 4c540fc9c7..8f3674aa8d 100644
--- a/ext/syslog/syslog.c
+++ b/ext/syslog/syslog.c
@@ -165,15 +165,15 @@ static VALUE mSyslog_open(int argc, VALUE *argv, VALUE self)
     syslog_ident = strdup(ident_ptr);
 
     if (NIL_P(opt)) {
-	syslog_options = LOG_PID | LOG_CONS;
+        syslog_options = LOG_PID | LOG_CONS;
     } else {
-	syslog_options = NUM2INT(opt);
+        syslog_options = NUM2INT(opt);
     }
 
     if (NIL_P(fac)) {
-	syslog_facility = LOG_USER;
+        syslog_facility = LOG_USER;
     } else {
-	syslog_facility = NUM2INT(fac);
+        syslog_facility = NUM2INT(fac);
     }
 
     openlog(syslog_ident, syslog_options, syslog_facility);
@@ -307,7 +307,7 @@ static VALUE mSyslog_log(int argc, VALUE *argv, VALUE self)
     pri = *argv++;
 
     if (!FIXNUM_P(pri)) {
-	rb_raise(rb_eTypeError, "type mismatch: %"PRIsVALUE" given", rb_obj_class(pri));
+        rb_raise(rb_eTypeError, "type mismatch: %"PRIsVALUE" given", rb_obj_class(pri));
     }
 
     syslog_write(FIX2INT(pri), argc, argv);
@@ -322,14 +322,14 @@ static VALUE mSyslog_inspect(VALUE self)
     Check_Type(self, T_MODULE);
 
     if (!syslog_opened)
-	return rb_sprintf("<#%"PRIsVALUE": opened=false>", self);
+        return rb_sprintf("<#%"PRIsVALUE": opened=false>", self);
 
     return rb_sprintf("<#%"PRIsVALUE": opened=true, ident=\"%s\", options=%d, facility=%d, mask=%d>",
-		      self,
-		      syslog_ident,
-		      syslog_options,
-		      syslog_facility,
-		      syslog_mask);
+                      self,
+                      syslog_ident,
+                      syslog_options,
+                      syslog_facility,
+                      syslog_mask);
 }
 
 /* Returns self, for backward compatibility.
diff --git a/ext/syslog/syslog.gemspec b/ext/syslog/syslog.gemspec
index 8f73f5ad0d..6aa2e9570d 100644
--- a/ext/syslog/syslog.gemspec
+++ b/ext/syslog/syslog.gemspec
@@ -1,6 +1,6 @@
 Gem::Specification.new do |spec|
   spec.name          = "syslog"
-  spec.version       = "0.1.0"
+  spec.version       = "0.1.1"
   spec.authors       = ["Akinori MUSHA"]
   spec.email         = ["knu@idaemons.org"]
 
diff --git a/ext/win32/lib/win32/registry.rb b/ext/win32/lib/win32/registry.rb
index b5b99ff684..bda8bb012f 100644
--- a/ext/win32/lib/win32/registry.rb
+++ b/ext/win32/lib/win32/registry.rb
@@ -69,7 +69,11 @@ For detail, see the MSDN[http://msdn.microsoft.com/library/en-us/sysinfo/base/pr
   WCHAR_NUL = "\0".encode(WCHAR).freeze
   WCHAR_CR = "\r".encode(WCHAR).freeze
   WCHAR_SIZE = WCHAR_NUL.bytesize
-  LOCALE = Encoding.find(Encoding.locale_charmap)
+  begin
+    LOCALE = Encoding.find(Encoding.locale_charmap)
+  rescue ArgumentError
+    LOCALE = Encoding::UTF_8
+  end
 
   class Registry
 
@@ -740,14 +744,11 @@ For detail, see the MSDN[http://msdn.microsoft.com/library/en-us/sysinfo/base/pr
     # method returns.
     #
     def write(name, type, data)
-      termsize = 0
       case type
       when REG_SZ, REG_EXPAND_SZ
-        data = data.encode(WCHAR)
-        termsize = WCHAR_SIZE
+        data = data.encode(WCHAR) << WCHAR_NUL
       when REG_MULTI_SZ
         data = data.to_a.map {|s| s.encode(WCHAR)}.join(WCHAR_NUL) << WCHAR_NUL
-        termsize = WCHAR_SIZE
       when REG_BINARY, REG_NONE
         data = data.to_s
       when REG_DWORD
@@ -759,7 +760,7 @@ For detail, see the MSDN[http://msdn.microsoft.com/library/en-us/sysinfo/base/pr
       else
         raise TypeError, "Unsupported type #{Registry.type2name(type)}"
       end
-      API.SetValue(@hkey, name, type, data, data.bytesize + termsize)
+      API.SetValue(@hkey, name, type, data, data.bytesize)
     end
 
     #
diff --git a/ext/win32/resolv/resolv.c b/ext/win32/resolv/resolv.c
index f19243ccc1..8a50ef7824 100644
--- a/ext/win32/resolv/resolv.c
+++ b/ext/win32/resolv/resolv.c
@@ -29,19 +29,19 @@ get_dns_server_list(VALUE self)
 
     ret = GetNetworkParams(NULL, &buflen);
     if (ret != NO_ERROR && ret != ERROR_BUFFER_OVERFLOW) {
-	w32error_raise(ret);
+        w32error_raise(ret);
     }
     fixedinfo = ALLOCV(buf, buflen);
     ret = GetNetworkParams(fixedinfo, &buflen);
     if (ret == NO_ERROR) {
-	const IP_ADDR_STRING *ipaddr = &fixedinfo->DnsServerList;
-	nameservers = rb_ary_new();
-	do {
-	    const char *s = ipaddr->IpAddress.String;
-	    if (!*s) continue;
-	    if (strcmp(s, "0.0.0.0") == 0) continue;
-	    rb_ary_push(nameservers, rb_str_new_cstr(s));
-	} while ((ipaddr = ipaddr->Next) != NULL);
+        const IP_ADDR_STRING *ipaddr = &fixedinfo->DnsServerList;
+        nameservers = rb_ary_new();
+        do {
+            const char *s = ipaddr->IpAddress.String;
+            if (!*s) continue;
+            if (strcmp(s, "0.0.0.0") == 0) continue;
+            rb_ary_push(nameservers, rb_str_new_cstr(s));
+        } while ((ipaddr = ipaddr->Next) != NULL);
     }
     ALLOCV_END(buf);
     if (ret != NO_ERROR) w32error_raise(ret);
diff --git a/ext/win32ole/win32ole.c b/ext/win32ole/win32ole.c
index d77347b3a3..3f083bb12d 100644
--- a/ext/win32ole/win32ole.c
+++ b/ext/win32ole/win32ole.c
@@ -454,12 +454,12 @@ vtdate2rbtime(double date)
     double sec;
     VariantTimeToSystemTime(date, &st);
     v = rb_funcall(rb_cTime, rb_intern("new"), 6,
-		      RB_INT2FIX(st.wYear),
-		      RB_INT2FIX(st.wMonth),
-		      RB_INT2FIX(st.wDay),
-		      RB_INT2FIX(st.wHour),
-		      RB_INT2FIX(st.wMinute),
-		      RB_INT2FIX(st.wSecond));
+                      RB_INT2FIX(st.wYear),
+                      RB_INT2FIX(st.wMonth),
+                      RB_INT2FIX(st.wDay),
+                      RB_INT2FIX(st.wHour),
+                      RB_INT2FIX(st.wMinute),
+                      RB_INT2FIX(st.wSecond));
     st.wYear = RB_FIX2INT(rb_funcall(v, rb_intern("year"), 0));
     st.wMonth = RB_FIX2INT(rb_funcall(v, rb_intern("month"), 0));
     st.wDay = RB_FIX2INT(rb_funcall(v, rb_intern("mday"), 0));
@@ -568,16 +568,16 @@ load_conv_function51932(void)
     void *p;
     if (!pIMultiLanguage) {
 #if defined(HAVE_TYPE_IMULTILANGUAGE2)
-	hr = CoCreateInstance(&CLSID_CMultiLanguage, NULL, CLSCTX_INPROC_SERVER,
-		              &IID_IMultiLanguage2, &p);
+        hr = CoCreateInstance(&CLSID_CMultiLanguage, NULL, CLSCTX_INPROC_SERVER,
+                              &IID_IMultiLanguage2, &p);
 #elif defined(HAVE_TYPE_IMULTILANGUAGE)
-	hr = CoCreateInstance(&CLSID_CMultiLanguage, NULL, CLSCTX_INPROC_SERVER,
-		              &IID_IMultiLanguage, &p);
+        hr = CoCreateInstance(&CLSID_CMultiLanguage, NULL, CLSCTX_INPROC_SERVER,
+                              &IID_IMultiLanguage, &p);
 #endif
-	if (FAILED(hr)) {
-	    failed_load_conv51932();
-	}
-	pIMultiLanguage = p;
+        if (FAILED(hr)) {
+            failed_load_conv51932();
+        }
+        pIMultiLanguage = p;
     }
 }
 #define need_conv_function51932() (load_conv_function51932(), 1)
@@ -624,7 +624,7 @@ ole_init_cp(void)
     rb_encoding *encdef;
     encdef = rb_default_internal_encoding();
     if (!encdef) {
-	encdef = rb_default_external_encoding();
+        encdef = rb_default_external_encoding();
     }
     cp = ole_encoding2cp(encdef);
     set_ole_codepage(cp);
@@ -650,38 +650,38 @@ ole_cp2encoding(UINT cp)
     int idx;
 
     if (!code_page_installed(cp)) {
-	switch(cp) {
-	  case CP_ACP:
-	    cp = GetACP();
-	    break;
-	  case CP_OEMCP:
-	    cp = GetOEMCP();
-	    break;
-	  case CP_MACCP:
-	  case CP_THREAD_ACP:
-	    if (!pGetCPInfoEx) {
-		pGetCPInfoEx = (BOOL (*)(UINT, DWORD, struct myCPINFOEX *))
-		    GetProcAddress(GetModuleHandle("kernel32"), "GetCPInfoEx");
-		if (!pGetCPInfoEx) {
-		    pGetCPInfoEx = (void*)-1;
-		}
-	    }
-	    buf = ALLOCA_N(struct myCPINFOEX, 1);
-	    ZeroMemory(buf, sizeof(struct myCPINFOEX));
-	    if (pGetCPInfoEx == (void*)-1 || !pGetCPInfoEx(cp, 0, buf)) {
-		rb_raise(eWIN32OLERuntimeError, "cannot map codepage to encoding.");
-		break;	/* never reach here */
-	    }
-	    cp = buf->CodePage;
-	    break;
-	  case CP_SYMBOL:
-	  case CP_UTF7:
-	  case CP_UTF8:
-	    break;
-	  case 51932:
-	    load_conv_function51932();
-	    break;
-	  default:
+        switch(cp) {
+          case CP_ACP:
+            cp = GetACP();
+            break;
+          case CP_OEMCP:
+            cp = GetOEMCP();
+            break;
+          case CP_MACCP:
+          case CP_THREAD_ACP:
+            if (!pGetCPInfoEx) {
+                pGetCPInfoEx = (BOOL (*)(UINT, DWORD, struct myCPINFOEX *))
+                    GetProcAddress(GetModuleHandle("kernel32"), "GetCPInfoEx");
+                if (!pGetCPInfoEx) {
+                    pGetCPInfoEx = (void*)-1;
+                }
+            }
+            buf = ALLOCA_N(struct myCPINFOEX, 1);
+            ZeroMemory(buf, sizeof(struct myCPINFOEX));
+            if (pGetCPInfoEx == (void*)-1 || !pGetCPInfoEx(cp, 0, buf)) {
+                rb_raise(eWIN32OLERuntimeError, "cannot map codepage to encoding.");
+                break;	/* never reach here */
+            }
+            cp = buf->CodePage;
+            break;
+          case CP_SYMBOL:
+          case CP_UTF7:
+          case CP_UTF8:
+            break;
+          case 51932:
+            load_conv_function51932();
+            break;
+          default:
             rb_raise(eWIN32OLERuntimeError, "codepage should be WIN32OLE::CP_ACP, WIN32OLE::CP_OEMCP, WIN32OLE::CP_MACCP, WIN32OLE::CP_THREAD_ACP, WIN32OLE::CP_SYMBOL, WIN32OLE::CP_UTF7, WIN32OLE::CP_UTF8, or installed codepage.");
             break;
         }
@@ -690,7 +690,7 @@ ole_cp2encoding(UINT cp)
     enc_name = rb_sprintf("CP%d", cp);
     idx = rb_enc_find_index(enc_cstr = StringValueCStr(enc_name));
     if (idx < 0)
-	idx = rb_define_dummy_encoding(enc_cstr);
+        idx = rb_define_dummy_encoding(enc_cstr);
     return rb_enc_from_index(idx);
 }
 
@@ -700,14 +700,14 @@ ole_ml_wc2mb_conv0(LPWSTR pw, LPSTR pm, UINT *size)
 {
     DWORD dw = 0;
     return pIMultiLanguage->lpVtbl->ConvertStringFromUnicode(pIMultiLanguage,
-		    &dw, cWIN32OLE_cp, pw, NULL, pm, size);
+                    &dw, cWIN32OLE_cp, pw, NULL, pm, size);
 }
 #define ole_ml_wc2mb_conv(pw, pm, size, onfailure) do { \
-	HRESULT hr = ole_ml_wc2mb_conv0(pw, pm, &size); \
-	if (FAILED(hr)) { \
-	    onfailure; \
-	    ole_raise(hr, eWIN32OLERuntimeError, "fail to convert Unicode to CP%d", cWIN32OLE_cp); \
-	} \
+        HRESULT hr = ole_ml_wc2mb_conv0(pw, pm, &size); \
+        if (FAILED(hr)) { \
+            onfailure; \
+            ole_raise(hr, eWIN32OLERuntimeError, "fail to convert Unicode to CP%d", cWIN32OLE_cp); \
+        } \
     } while (0)
 #endif
 
@@ -720,11 +720,11 @@ ole_wc2mb_alloc(LPWSTR pw, char *(alloc)(UINT size, void *arg), void *arg)
     UINT size = 0;
     if (conv_51932(cWIN32OLE_cp)) {
 #ifndef pIMultiLanguage
-	ole_ml_wc2mb_conv(pw, NULL, size, {});
-	pm = alloc(size, arg);
-	if (size) ole_ml_wc2mb_conv(pw, pm, size, xfree(pm));
-	pm[size] = '\0';
-	return pm;
+        ole_ml_wc2mb_conv(pw, NULL, size, {});
+        pm = alloc(size, arg);
+        if (size) ole_ml_wc2mb_conv(pw, pm, size, xfree(pm));
+        pm[size] = '\0';
+        return pm;
 #endif
     }
     size = ole_wc2mb_conv(pw, NULL, 0);
@@ -816,8 +816,8 @@ ole_initialize(void)
     HRESULT hr;
 
     if(!g_uninitialize_hooked) {
-	rb_add_event_hook(ole_uninitialize_hook, RUBY_EVENT_THREAD_END, Qnil);
-	g_uninitialize_hooked = TRUE;
+        rb_add_event_hook(ole_uninitialize_hook, RUBY_EVENT_THREAD_END, Qnil);
+        g_uninitialize_hooked = TRUE;
     }
 
     if(g_ole_initialized == FALSE) {
@@ -911,21 +911,21 @@ ole_mb2wc(char *pm, int len, UINT cp)
 
     if (conv_51932(cp)) {
 #ifndef pIMultiLanguage
-	DWORD dw = 0;
-	UINT n = len;
-	HRESULT hr = pIMultiLanguage->lpVtbl->ConvertStringToUnicode(pIMultiLanguage,
-		&dw, cp, pm, &n, NULL, &size);
-	if (FAILED(hr)) {
+        DWORD dw = 0;
+        UINT n = len;
+        HRESULT hr = pIMultiLanguage->lpVtbl->ConvertStringToUnicode(pIMultiLanguage,
+                &dw, cp, pm, &n, NULL, &size);
+        if (FAILED(hr)) {
             ole_raise(hr, eWIN32OLERuntimeError, "fail to convert CP%d to Unicode", cp);
-	}
-	pw = SysAllocStringLen(NULL, size);
-	n = len;
-	hr = pIMultiLanguage->lpVtbl->ConvertStringToUnicode(pIMultiLanguage,
-		&dw, cp, pm, &n, pw, &size);
-	if (FAILED(hr)) {
+        }
+        pw = SysAllocStringLen(NULL, size);
+        n = len;
+        hr = pIMultiLanguage->lpVtbl->ConvertStringToUnicode(pIMultiLanguage,
+                &dw, cp, pm, &n, pw, &size);
+        if (FAILED(hr)) {
             ole_raise(hr, eWIN32OLERuntimeError, "fail to convert CP%d to Unicode", cp);
-	}
-	return pw;
+        }
+        return pw;
 #endif
     }
     size = MultiByteToWideChar(cp, 0, pm, len, NULL, 0);
@@ -1737,11 +1737,11 @@ reg_get_val(HKEY hkey, const char *subkey)
         if (err == ERROR_SUCCESS) {
             pbuf[size] = '\0';
             if (dwtype == REG_EXPAND_SZ) {
-		char* pbuf2 = (char *)pbuf;
-		DWORD len = ExpandEnvironmentStrings(pbuf2, NULL, 0);
-		pbuf = ALLOC_N(char, len + 1);
-		ExpandEnvironmentStrings(pbuf2, pbuf, len + 1);
-		free(pbuf2);
+                char* pbuf2 = (char *)pbuf;
+                DWORD len = ExpandEnvironmentStrings(pbuf2, NULL, 0);
+                pbuf = ALLOC_N(char, len + 1);
+                ExpandEnvironmentStrings(pbuf2, pbuf, len + 1);
+                free(pbuf2);
             }
             val = rb_str_new2((char *)pbuf);
         }
@@ -2555,7 +2555,7 @@ hash2named_arg(VALUE key, VALUE val, VALUE pop)
         rb_raise(rb_eTypeError, "wrong argument type (expected String or Symbol)");
     }
     if (RB_TYPE_P(key, T_SYMBOL)) {
-	key = rb_sym2str(key);
+        key = rb_sym2str(key);
     }
 
     /* pNamedArgs[0] is <method name>, so "index + 1" */
@@ -2619,10 +2619,10 @@ ole_invoke(int argc, VALUE *argv, VALUE self, USHORT wFlags, BOOL is_bracket)
 
     rb_scan_args(argc, argv, "1*", &cmd, &paramS);
     if(!RB_TYPE_P(cmd, T_STRING) && !RB_TYPE_P(cmd, T_SYMBOL) && !is_bracket) {
-	rb_raise(rb_eTypeError, "method is wrong type (expected String or Symbol)");
+        rb_raise(rb_eTypeError, "method is wrong type (expected String or Symbol)");
     }
     if (RB_TYPE_P(cmd, T_SYMBOL)) {
-	cmd = rb_sym2str(cmd);
+        cmd = rb_sym2str(cmd);
     }
     pole = oledata_get_struct(self);
     if(!pole->pDispatch) {
@@ -2631,7 +2631,7 @@ ole_invoke(int argc, VALUE *argv, VALUE self, USHORT wFlags, BOOL is_bracket)
     if (is_bracket) {
         DispID = DISPID_VALUE;
         argc += 1;
-	rb_ary_unshift(paramS, cmd);
+        rb_ary_unshift(paramS, cmd);
     } else {
         wcmdname = ole_vstr2wc(cmd);
         hr = pole->pDispatch->lpVtbl->GetIDsOfNames( pole->pDispatch, &IID_NULL,
@@ -3639,7 +3639,7 @@ fole_respond_to(VALUE self, VALUE method)
     pole = oledata_get_struct(self);
     wcmdname = ole_vstr2wc(method);
     hr = pole->pDispatch->lpVtbl->GetIDsOfNames( pole->pDispatch, &IID_NULL,
-	    &wcmdname, 1, cWIN32OLE_lcid, &DispID);
+            &wcmdname, 1, cWIN32OLE_lcid, &DispID);
     SysFreeString(wcmdname);
     return SUCCEEDED(hr) ? Qtrue : Qfalse;
 }
diff --git a/ext/win32ole/win32ole.gemspec b/ext/win32ole/win32ole.gemspec
index 977555c98d..b6ea8e8a55 100644
--- a/ext/win32ole/win32ole.gemspec
+++ b/ext/win32ole/win32ole.gemspec
@@ -1,6 +1,6 @@
 Gem::Specification.new do |spec|
   spec.name          = "win32ole"
-  spec.version       = "1.8.8"
+  spec.version       = "1.8.9"
   spec.authors       = ["Masaki Suketa"]
   spec.email         = ["suke@ruby-lang.org"]
 
diff --git a/ext/win32ole/win32ole_event.c b/ext/win32ole/win32ole_event.c
index 93e4d6bad5..45ebf13433 100644
--- a/ext/win32ole/win32ole_event.c
+++ b/ext/win32ole/win32ole_event.c
@@ -200,7 +200,7 @@ STDMETHODIMP EVENTSINK_Invoke(
     }
     outargv = Qnil;
     if (is_outarg == Qtrue) {
-	outargv = rb_ary_new();
+        outargv = rb_ary_new();
         rb_ary_push(args, outargv);
     }
 
@@ -413,15 +413,15 @@ hash2ptr_dispparams(VALUE hash, ITypeInfo *pTypeInfo, DISPID dispid, DISPPARAMS
                                      bstrs, pdispparams->cArgs + 1,
                                      &len);
     if (FAILED(hr))
-	return;
+        return;
 
     for (i = 0; i < len - 1; i++) {
-	key = WC2VSTR(bstrs[i + 1]);
+        key = WC2VSTR(bstrs[i + 1]);
         val = rb_hash_aref(hash, RB_UINT2NUM(i));
-	if (val == Qnil)
-	    val = rb_hash_aref(hash, key);
-	if (val == Qnil)
-	    val = rb_hash_aref(hash, rb_str_intern(key));
+        if (val == Qnil)
+            val = rb_hash_aref(hash, key);
+        if (val == Qnil)
+            val = rb_hash_aref(hash, rb_str_intern(key));
         pvar = &pdispparams->rgvarg[pdispparams->cArgs-i-1];
         ole_val2ptr_variant(val, pvar);
     }
@@ -433,7 +433,7 @@ hash2result(VALUE hash)
     VALUE ret = Qnil;
     ret = rb_hash_aref(hash, rb_str_new2("return"));
     if (ret == Qnil)
-	ret = rb_hash_aref(hash, rb_str_intern(rb_str_new2("return")));
+        ret = rb_hash_aref(hash, rb_str_intern(rb_str_new2("return")));
     return ret;
 }
 
@@ -610,7 +610,7 @@ find_coclass(
 
     hr = pTypeInfo->lpVtbl->GetContainingTypeLib(pTypeInfo, &pTypeLib, NULL);
     if (FAILED(hr)) {
-	return hr;
+        return hr;
     }
     count = pTypeLib->lpVtbl->GetTypeInfoCount(pTypeLib);
     for (i = 0; i < count && !found; i++) {
diff --git a/ext/win32ole/win32ole_typelib.c b/ext/win32ole/win32ole_typelib.c
index 651dc2d75f..fb68bebda8 100644
--- a/ext/win32ole/win32ole_typelib.c
+++ b/ext/win32ole/win32ole_typelib.c
@@ -285,7 +285,7 @@ oletypelib_get_libattr(ITypeLib *pTypeLib, TLIBATTR **ppTLibAttr)
     hr = pTypeLib->lpVtbl->GetLibAttr(pTypeLib, ppTLibAttr);
     if (FAILED(hr)) {
         ole_raise(hr, eWIN32OLERuntimeError,
-		  "failed to get library attribute(TLIBATTR) from ITypeLib");
+                  "failed to get library attribute(TLIBATTR) from ITypeLib");
     }
 }
 
@@ -588,13 +588,13 @@ foletypelib_path(VALUE self)
     pTypeLib = itypelib(self);
     oletypelib_get_libattr(pTypeLib, &pTLibAttr);
     hr = QueryPathOfRegTypeLib(&pTLibAttr->guid,
-	                       pTLibAttr->wMajorVerNum,
-			       pTLibAttr->wMinorVerNum,
-			       lcid,
-			       &bstr);
+                               pTLibAttr->wMajorVerNum,
+                               pTLibAttr->wMinorVerNum,
+                               lcid,
+                               &bstr);
     if (FAILED(hr)) {
-	pTypeLib->lpVtbl->ReleaseTLibAttr(pTypeLib, pTLibAttr);
-	ole_raise(hr, eWIN32OLERuntimeError, "failed to QueryPathOfRegTypeTypeLib");
+        pTypeLib->lpVtbl->ReleaseTLibAttr(pTypeLib, pTLibAttr);
+        ole_raise(hr, eWIN32OLERuntimeError, "failed to QueryPathOfRegTypeTypeLib");
     }
 
     pTypeLib->lpVtbl->ReleaseTLibAttr(pTypeLib, pTLibAttr);
@@ -722,7 +722,7 @@ typelib_file_from_typelib(VALUE ole)
             if (ver == Qnil)
                 break;
             err = reg_open_vkey(hclsid, ver, &hversion);
-			if (err != ERROR_SUCCESS || fver > atof(StringValuePtr(ver)))
+                        if (err != ERROR_SUCCESS || fver > atof(StringValuePtr(ver)))
                 continue;
             fver = atof(StringValuePtr(ver));
             typelib = reg_get_val(hversion, NULL);
diff --git a/ext/zlib/zlib.c b/ext/zlib/zlib.c
index 20079a5d4c..aefdba0ebd 100644
--- a/ext/zlib/zlib.c
+++ b/ext/zlib/zlib.c
@@ -25,7 +25,7 @@
 # define VALGRIND_MAKE_MEM_UNDEFINED(p, n) 0
 #endif
 
-#define RUBY_ZLIB_VERSION "2.1.1"
+#define RUBY_ZLIB_VERSION "3.0.0"
 
 #ifndef RB_PASS_CALLED_KEYWORDS
 # define rb_class_new_instance_kw(argc, argv, klass, kw_splat) rb_class_new_instance(argc, argv, klass)
diff --git a/file.c b/file.c
index e65e548c9a..3a8439ef07 100644
--- a/file.c
+++ b/file.c
@@ -115,6 +115,8 @@ int flock(int, int);
 # define link(f, t)      rb_w32_ulink((f), (t))
 # undef unlink
 # define unlink(p)       rb_w32_uunlink(p)
+# undef readlink
+# define readlink(f, t, l)    rb_w32_ureadlink((f), (t), (l))
 # undef rename
 # define rename(f, t)    rb_w32_urename((f), (t))
 # undef symlink
@@ -182,15 +184,15 @@ file_path_convert(VALUE name)
     int fname_encidx = ENCODING_GET(name);
     int fs_encidx;
     if (ENCINDEX_US_ASCII != fname_encidx &&
-	ENCINDEX_ASCII != fname_encidx &&
-	(fs_encidx = rb_filesystem_encindex()) != fname_encidx &&
-	rb_default_internal_encoding() &&
-	!rb_enc_str_asciionly_p(name)) {
-	/* Don't call rb_filesystem_encoding() before US-ASCII and ASCII-8BIT */
-	/* fs_encoding should be ascii compatible */
-	rb_encoding *fname_encoding = rb_enc_from_index(fname_encidx);
-	rb_encoding *fs_encoding = rb_enc_from_index(fs_encidx);
-	name = rb_str_conv_enc(name, fname_encoding, fs_encoding);
+        ENCINDEX_ASCII_8BIT != fname_encidx &&
+        (fs_encidx = rb_filesystem_encindex()) != fname_encidx &&
+        rb_default_internal_encoding() &&
+        !rb_enc_str_asciionly_p(name)) {
+        /* Don't call rb_filesystem_encoding() before US-ASCII and ASCII-8BIT */
+        /* fs_encoding should be ascii compatible */
+        rb_encoding *fname_encoding = rb_enc_from_index(fname_encidx);
+        rb_encoding *fs_encoding = rb_enc_from_index(fs_encidx);
+        name = rb_str_conv_enc(name, fname_encoding, fs_encoding);
     }
 #endif
     return name;
@@ -201,8 +203,8 @@ check_path_encoding(VALUE str)
 {
     rb_encoding *enc = rb_enc_get(str);
     if (!rb_enc_asciicompat(enc)) {
-	rb_raise(rb_eEncCompatError, "path name must be ASCII-compatible (%s): %"PRIsVALUE,
-		 rb_enc_name(enc), rb_str_inspect(str));
+        rb_raise(rb_eEncCompatError, "path name must be ASCII-compatible (%s): %"PRIsVALUE,
+                 rb_enc_name(enc), rb_str_inspect(str));
     }
     return enc;
 }
@@ -214,7 +216,7 @@ rb_get_path_check_to_string(VALUE obj)
     ID to_path;
 
     if (RB_TYPE_P(obj, T_STRING)) {
-	return obj;
+        return obj;
     }
     CONST_ID(to_path, "to_path");
     tmp = rb_check_funcall_default(obj, to_path, 0, 0, obj);
@@ -229,7 +231,7 @@ rb_get_path_check_convert(VALUE obj)
 
     check_path_encoding(obj);
     if (!rb_str_to_cstr(obj)) {
-	rb_raise(rb_eArgError, "path name contains null byte");
+        rb_raise(rb_eArgError, "path name contains null byte");
     }
 
     return rb_str_new4(obj);
@@ -253,14 +255,14 @@ rb_str_encode_ospath(VALUE path)
 #if USE_OSPATH
     int encidx = ENCODING_GET(path);
 #if 0 && defined _WIN32
-    if (encidx == ENCINDEX_ASCII) {
-	encidx = rb_filesystem_encindex();
+    if (encidx == ENCINDEX_ASCII_8BIT) {
+        encidx = rb_filesystem_encindex();
     }
 #endif
-    if (encidx != ENCINDEX_ASCII && encidx != ENCINDEX_UTF_8) {
-	rb_encoding *enc = rb_enc_from_index(encidx);
-	rb_encoding *utf8 = rb_utf8_encoding();
-	path = rb_str_conv_enc(path, enc, utf8);
+    if (encidx != ENCINDEX_ASCII_8BIT && encidx != ENCINDEX_UTF_8) {
+        rb_encoding *enc = rb_enc_from_index(encidx);
+        rb_encoding *utf8 = rb_utf8_encoding();
+        path = rb_str_conv_enc(path, enc, utf8);
     }
 #endif
     return path;
@@ -268,15 +270,55 @@ rb_str_encode_ospath(VALUE path)
 
 #ifdef __APPLE__
 # define NORMALIZE_UTF8PATH 1
+
+# ifdef HAVE_WORKING_FORK
+static void
+rb_CFString_class_initialize_before_fork(void)
+{
+    /*
+     * Since macOS 13, CFString family API used in
+     * rb_str_append_normalized_ospath may internally use Objective-C classes
+     * (NSTaggedPointerString and NSPlaceholderMutableString) for small strings.
+     *
+     * On the other hand, Objective-C classes should not be used for the first
+     * time in a fork()'ed but not exec()'ed process. Violations for this rule
+     * can result deadlock during class initialization, so Objective-C runtime
+     * conservatively crashes on such cases by default.
+     *
+     * Therefore, we need to use CFString API to initialize Objective-C classes
+     * used internally *before* fork().
+     *
+     * For future changes, please note that this initialization process cannot
+     * be done in ctor because NSTaggedPointerString in CoreFoundation is enabled
+     * after CFStringInitializeTaggedStrings(), which is called during loading
+     * Objective-C runtime after ctor.
+     * For more details, see https://bugs.ruby-lang.org/issues/18912
+     */
+
+    /* Enough small but non-empty ASCII string to fit in NSTaggedPointerString. */
+    const char small_str[] = "/";
+    long len = sizeof(small_str) - 1;
+
+    const CFAllocatorRef alloc = kCFAllocatorDefault;
+    CFStringRef s = CFStringCreateWithBytesNoCopy(alloc,
+                                                  (const UInt8 *)small_str,
+                                                  len, kCFStringEncodingUTF8,
+                                                  FALSE, kCFAllocatorNull);
+    CFMutableStringRef m = CFStringCreateMutableCopy(alloc, len, s);
+    CFRelease(m);
+    CFRelease(s);
+}
+# endif
+
 static VALUE
 rb_str_append_normalized_ospath(VALUE str, const char *ptr, long len)
 {
     CFIndex buflen = 0;
     CFRange all;
     CFStringRef s = CFStringCreateWithBytesNoCopy(kCFAllocatorDefault,
-						  (const UInt8 *)ptr, len,
-						  kCFStringEncodingUTF8, FALSE,
-						  kCFAllocatorNull);
+                                                  (const UInt8 *)ptr, len,
+                                                  kCFStringEncodingUTF8, FALSE,
+                                                  kCFAllocatorNull);
     CFMutableStringRef m = CFStringCreateMutableCopy(kCFAllocatorDefault, len, s);
     long oldlen = RSTRING_LEN(str);
 
@@ -285,7 +327,7 @@ rb_str_append_normalized_ospath(VALUE str, const char *ptr, long len)
     CFStringGetBytes(m, all, kCFStringEncodingUTF8, '?', FALSE, NULL, 0, &buflen);
     rb_str_modify_expand(str, buflen);
     CFStringGetBytes(m, all, kCFStringEncodingUTF8, '?', FALSE,
-		     (UInt8 *)(RSTRING_PTR(str) + oldlen), buflen, &buflen);
+                     (UInt8 *)(RSTRING_PTR(str) + oldlen), buflen, &buflen);
     rb_str_set_len(str, oldlen + buflen);
     CFRelease(m);
     CFRelease(s);
@@ -303,34 +345,34 @@ rb_str_normalize_ospath(const char *ptr, long len)
     rb_enc_associate(str, enc);
 
     while (p < e) {
-	int l, c;
-	int r = rb_enc_precise_mbclen(p, e, enc);
-	if (!MBCLEN_CHARFOUND_P(r)) {
-	    /* invalid byte shall not happen but */
-	    static const char invalid[3] = "\xEF\xBF\xBD";
-	    rb_str_append_normalized_ospath(str, p1, p-p1);
-	    rb_str_cat(str, invalid, sizeof(invalid));
-	    p += 1;
-	    p1 = p;
-	    continue;
-	}
-	l = MBCLEN_CHARFOUND_LEN(r);
-	c = rb_enc_mbc_to_codepoint(p, e, enc);
-	if ((0x2000 <= c && c <= 0x2FFF) || (0xF900 <= c && c <= 0xFAFF) ||
-		(0x2F800 <= c && c <= 0x2FAFF)) {
-	    if (p - p1 > 0) {
-		rb_str_append_normalized_ospath(str, p1, p-p1);
-	    }
-	    rb_str_cat(str, p, l);
-	    p += l;
-	    p1 = p;
-	}
-	else {
-	    p += l;
-	}
+        int l, c;
+        int r = rb_enc_precise_mbclen(p, e, enc);
+        if (!MBCLEN_CHARFOUND_P(r)) {
+            /* invalid byte shall not happen but */
+            static const char invalid[3] = "\xEF\xBF\xBD";
+            rb_str_append_normalized_ospath(str, p1, p-p1);
+            rb_str_cat(str, invalid, sizeof(invalid));
+            p += 1;
+            p1 = p;
+            continue;
+        }
+        l = MBCLEN_CHARFOUND_LEN(r);
+        c = rb_enc_mbc_to_codepoint(p, e, enc);
+        if ((0x2000 <= c && c <= 0x2FFF) || (0xF900 <= c && c <= 0xFAFF) ||
+                (0x2F800 <= c && c <= 0x2FAFF)) {
+            if (p - p1 > 0) {
+                rb_str_append_normalized_ospath(str, p1, p-p1);
+            }
+            rb_str_cat(str, p, l);
+            p += l;
+            p1 = p;
+        }
+        else {
+            p += l;
+        }
     }
     if (p - p1 > 0) {
-	rb_str_append_normalized_ospath(str, p1, p-p1);
+        rb_str_append_normalized_ospath(str, p1, p-p1);
     }
 
     return str;
@@ -343,27 +385,27 @@ ignored_char_p(const char *p, const char *e, rb_encoding *enc)
     if (p+3 > e) return 0;
     switch ((unsigned char)*p) {
       case 0xe2:
-	switch ((unsigned char)p[1]) {
-	  case 0x80:
-	    c = (unsigned char)p[2];
-	    /* c >= 0x200c && c <= 0x200f */
-	    if (c >= 0x8c && c <= 0x8f) return 3;
-	    /* c >= 0x202a && c <= 0x202e */
-	    if (c >= 0xaa && c <= 0xae) return 3;
-	    return 0;
-	  case 0x81:
-	    c = (unsigned char)p[2];
-	    /* c >= 0x206a && c <= 0x206f */
-	    if (c >= 0xaa && c <= 0xaf) return 3;
-	    return 0;
-	}
-	break;
+        switch ((unsigned char)p[1]) {
+          case 0x80:
+            c = (unsigned char)p[2];
+            /* c >= 0x200c && c <= 0x200f */
+            if (c >= 0x8c && c <= 0x8f) return 3;
+            /* c >= 0x202a && c <= 0x202e */
+            if (c >= 0xaa && c <= 0xae) return 3;
+            return 0;
+          case 0x81:
+            c = (unsigned char)p[2];
+            /* c >= 0x206a && c <= 0x206f */
+            if (c >= 0xaa && c <= 0xaf) return 3;
+            return 0;
+        }
+        break;
       case 0xef:
-	/* c == 0xfeff */
-	if ((unsigned char)p[1] == 0xbb &&
-	    (unsigned char)p[2] == 0xbf)
-	    return 3;
-	break;
+        /* c == 0xfeff */
+        if ((unsigned char)p[1] == 0xbb &&
+            (unsigned char)p[2] == 0xbf)
+            return 3;
+        break;
     }
     return 0;
 }
@@ -393,10 +435,10 @@ no_gvl_apply2files(void *ptr)
     struct apply_arg *aa = ptr;
 
     for (aa->i = 0; aa->i < aa->argc; aa->i++) {
-	if (aa->func(aa->fn[aa->i].ptr, aa->arg) < 0) {
-	    aa->errnum = errno;
-	    break;
-	}
+        if (aa->func(aa->fn[aa->i].ptr, aa->arg) < 0) {
+            aa->errnum = errno;
+            break;
+        }
     }
     return 0;
 }
@@ -420,63 +462,28 @@ apply2files(int (*func)(const char *, void *), int argc, VALUE *argv, void *arg)
     aa->func = func;
 
     for (aa->i = 0; aa->i < argc; aa->i++) {
-	VALUE path = rb_get_path(argv[aa->i]);
+        VALUE path = rb_get_path(argv[aa->i]);
 
-	path = rb_str_encode_ospath(path);
-	aa->fn[aa->i].ptr = RSTRING_PTR(path);
-	aa->fn[aa->i].path = path;
+        path = rb_str_encode_ospath(path);
+        aa->fn[aa->i].ptr = RSTRING_PTR(path);
+        aa->fn[aa->i].path = path;
     }
 
     rb_thread_call_without_gvl(no_gvl_apply2files, aa, RUBY_UBF_IO, 0);
     if (aa->errnum) {
 #ifdef UTIME_EINVAL
-	if (func == utime_internal) {
-	    utime_failed(aa);
-	}
+        if (func == utime_internal) {
+            utime_failed(aa);
+        }
 #endif
-	rb_syserr_fail_path(aa->errnum, aa->fn[aa->i].path);
+        rb_syserr_fail_path(aa->errnum, aa->fn[aa->i].path);
     }
     if (v) {
-	ALLOCV_END(v);
+        ALLOCV_END(v);
     }
     return LONG2FIX(argc);
 }
 
-/*
- *  call-seq:
- *     file.path  ->  filename
- *     file.to_path  ->  filename
- *
- *  Returns the pathname used to create <i>file</i> as a string. Does
- *  not normalize the name.
- *
- *  The pathname may not point to the file corresponding to <i>file</i>.
- *  For instance, the pathname becomes void when the file has been
- *  moved or deleted.
- *
- *  This method raises IOError for a <i>file</i> created using
- *  File::Constants::TMPFILE because they don't have a pathname.
- *
- *     File.new("testfile").path               #=> "testfile"
- *     File.new("/tmp/../tmp/xxx", "w").path   #=> "/tmp/../tmp/xxx"
- *
- */
-
-static VALUE
-rb_file_path(VALUE obj)
-{
-    rb_io_t *fptr;
-
-    fptr = RFILE(rb_io_taint_check(obj))->fptr;
-    rb_io_check_initialized(fptr);
-
-    if (NIL_P(fptr->pathv)) {
-        rb_raise(rb_eIOError, "File is unnamed (TMPFILE?)");
-    }
-
-    return rb_str_dup(fptr->pathv);
-}
-
 static size_t
 stat_memsize(const void *p)
 {
@@ -496,9 +503,9 @@ stat_new_0(VALUE klass, const struct stat *st)
     VALUE obj = TypedData_Wrap_Struct(klass, &stat_data_type, 0);
 
     if (st) {
-	nst = ALLOC(struct stat);
-	*nst = *st;
-	RTYPEDDATA_DATA(obj) = nst;
+        nst = ALLOC(struct stat);
+        *nst = *st;
+        RTYPEDDATA_DATA(obj) = nst;
     }
     return obj;
 }
@@ -978,7 +985,7 @@ rb_stat_atime(VALUE self)
 
 /*
  *  call-seq:
- *     stat.mtime  ->  aTime
+ *     stat.mtime  ->  time
  *
  *  Returns the modification time of <i>stat</i>.
  *
@@ -994,7 +1001,7 @@ rb_stat_mtime(VALUE self)
 
 /*
  *  call-seq:
- *     stat.ctime  ->  aTime
+ *     stat.ctime  ->  time
  *
  *  Returns the change time for <i>stat</i> (that is, the time
  *  directory information about the file was changed, not the file
@@ -1015,7 +1022,7 @@ rb_stat_ctime(VALUE self)
 #if defined(HAVE_STAT_BIRTHTIME)
 /*
  *  call-seq:
- *     stat.birthtime  ->  aTime
+ *     stat.birthtime  ->  time
  *
  *  Returns the birth time for <i>stat</i>.
  *
@@ -1065,24 +1072,24 @@ rb_stat_inspect(VALUE self)
     VALUE str;
     size_t i;
     static const struct {
-	const char *name;
-	VALUE (*func)(VALUE);
+        const char *name;
+        VALUE (*func)(VALUE);
     } member[] = {
-	{"dev",	    rb_stat_dev},
-	{"ino",	    rb_stat_ino},
-	{"mode",    rb_stat_mode},
-	{"nlink",   rb_stat_nlink},
-	{"uid",	    rb_stat_uid},
-	{"gid",	    rb_stat_gid},
-	{"rdev",    rb_stat_rdev},
-	{"size",    rb_stat_size},
-	{"blksize", rb_stat_blksize},
-	{"blocks",  rb_stat_blocks},
-	{"atime",   rb_stat_atime},
-	{"mtime",   rb_stat_mtime},
-	{"ctime",   rb_stat_ctime},
+        {"dev",	    rb_stat_dev},
+        {"ino",	    rb_stat_ino},
+        {"mode",    rb_stat_mode},
+        {"nlink",   rb_stat_nlink},
+        {"uid",	    rb_stat_uid},
+        {"gid",	    rb_stat_gid},
+        {"rdev",    rb_stat_rdev},
+        {"size",    rb_stat_size},
+        {"blksize", rb_stat_blksize},
+        {"blocks",  rb_stat_blocks},
+        {"atime",   rb_stat_atime},
+        {"mtime",   rb_stat_mtime},
+        {"ctime",   rb_stat_ctime},
 #if defined(HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC)
-	{"birthtime",   rb_stat_birthtime},
+        {"birthtime",   rb_stat_birthtime},
 #endif
     };
 
@@ -1097,23 +1104,23 @@ rb_stat_inspect(VALUE self)
     rb_str_buf_cat2(str, " ");
 
     for (i = 0; i < sizeof(member)/sizeof(member[0]); i++) {
-	VALUE v;
-
-	if (i > 0) {
-	    rb_str_buf_cat2(str, ", ");
-	}
-	rb_str_buf_cat2(str, member[i].name);
-	rb_str_buf_cat2(str, "=");
-	v = (*member[i].func)(self);
-	if (i == 2) {		/* mode */
-	    rb_str_catf(str, "0%lo", (unsigned long)NUM2ULONG(v));
-	}
-	else if (i == 0 || i == 6) { /* dev/rdev */
-	    rb_str_catf(str, "0x%"PRI_DEVT_PREFIX"x", NUM2DEVT(v));
-	}
-	else {
-	    rb_str_append(str, rb_inspect(v));
-	}
+        VALUE v;
+
+        if (i > 0) {
+            rb_str_buf_cat2(str, ", ");
+        }
+        rb_str_buf_cat2(str, member[i].name);
+        rb_str_buf_cat2(str, "=");
+        v = (*member[i].func)(self);
+        if (i == 2) {		/* mode */
+            rb_str_catf(str, "0%lo", (unsigned long)NUM2ULONG(v));
+        }
+        else if (i == 0 || i == 6) { /* dev/rdev */
+            rb_str_catf(str, "0x%"PRI_DEVT_PREFIX"x", NUM2DEVT(v));
+        }
+        else {
+            rb_str_append(str, rb_inspect(v));
+        }
     }
     rb_str_buf_cat2(str, ">");
 
@@ -1123,8 +1130,8 @@ rb_stat_inspect(VALUE self)
 typedef struct no_gvl_stat_data {
     struct stat *st;
     union {
-	const char *path;
-	int fd;
+        const char *path;
+        int fd;
     } file;
 } no_gvl_stat_data;
 
@@ -1162,7 +1169,7 @@ stat_without_gvl(const char *path, struct stat *st)
     data.st = st;
 
     return (int)(VALUE)rb_thread_call_without_gvl(no_gvl_stat, &data,
-						  RUBY_UBF_IO, NULL);
+                                                  RUBY_UBF_IO, NULL);
 }
 
 #if !defined(HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC) && \
@@ -1292,16 +1299,16 @@ rb_stat(VALUE file, struct stat *st)
 
     tmp = rb_check_convert_type_with_id(file, T_FILE, "IO", idTo_io);
     if (!NIL_P(tmp)) {
-	rb_io_t *fptr;
+        rb_io_t *fptr;
 
-	GetOpenFile(tmp, fptr);
-	result = fstat_without_gvl(fptr->fd, st);
-	file = tmp;
+        GetOpenFile(tmp, fptr);
+        result = fstat_without_gvl(fptr->fd, st);
+        file = tmp;
     }
     else {
-	FilePathValue(file);
-	file = rb_str_encode_ospath(file);
-	result = stat_without_gvl(RSTRING_PTR(file), st);
+        FilePathValue(file);
+        file = rb_str_encode_ospath(file);
+        result = stat_without_gvl(RSTRING_PTR(file), st);
     }
     RB_GC_GUARD(file);
     return result;
@@ -1309,11 +1316,11 @@ rb_stat(VALUE file, struct stat *st)
 
 /*
  *  call-seq:
- *     File.stat(file_name)   ->  stat
+ *    File.stat(filepath) ->  stat
  *
- *  Returns a File::Stat object for the named file (see File::Stat).
+ *  Returns a File::Stat object for the file at +filepath+ (see File::Stat):
  *
- *     File.stat("testfile").mtime   #=> Tue Apr 08 12:58:04 CDT 2003
+ *    File.stat('t.txt').class # => File::Stat
  *
  */
 
@@ -1325,7 +1332,7 @@ rb_file_s_stat(VALUE klass, VALUE fname)
     FilePathValue(fname);
     fname = rb_str_encode_ospath(fname);
     if (stat_without_gvl(RSTRING_PTR(fname), &st) < 0) {
-	rb_sys_fail_path(fname);
+        rb_sys_fail_path(fname);
     }
     return rb_stat_new(&st);
 }
@@ -1353,7 +1360,7 @@ rb_io_stat(VALUE obj)
 
     GetOpenFile(obj, fptr);
     if (fstat(fptr->fd, &st) == -1) {
-	rb_sys_fail_path(fptr->pathv);
+        rb_sys_fail_path(fptr->pathv);
     }
     return rb_stat_new(&st);
 }
@@ -1375,21 +1382,20 @@ lstat_without_gvl(const char *path, struct stat *st)
     data.st = st;
 
     return (int)(VALUE)rb_thread_call_without_gvl(no_gvl_lstat, &data,
-						    RUBY_UBF_IO, NULL);
+                                                    RUBY_UBF_IO, NULL);
 }
 #endif /* HAVE_LSTAT */
 
 /*
  *  call-seq:
- *     File.lstat(file_name)   -> stat
+ *    File.lstat(filepath) -> stat
  *
- *  Same as File::stat, but does not follow the last symbolic link.
- *  Instead, reports on the link itself.
+ *  Like File::stat, but does not follow the last symbolic link;
+ *  instead, returns a File::Stat object for the link itself.
  *
- *     File.symlink("testfile", "link2test")   #=> 0
- *     File.stat("testfile").size              #=> 66
- *     File.lstat("link2test").size            #=> 8
- *     File.stat("link2test").size             #=> 66
+ *    File.symlink('t.txt', 'symlink')
+ *    File.stat('symlink').size  # => 47
+ *    File.lstat('symlink').size # => 5
  *
  */
 
@@ -1402,7 +1408,7 @@ rb_file_s_lstat(VALUE klass, VALUE fname)
     FilePathValue(fname);
     fname = rb_str_encode_ospath(fname);
     if (lstat_without_gvl(StringValueCStr(fname), &st) == -1) {
-	rb_sys_fail_path(fname);
+        rb_sys_fail_path(fname);
     }
     return rb_stat_new(&st);
 #else
@@ -1412,16 +1418,16 @@ rb_file_s_lstat(VALUE klass, VALUE fname)
 
 /*
  *  call-seq:
- *     file.lstat   ->  stat
+ *    lstat -> stat
  *
- *  Same as IO#stat, but does not follow the last symbolic link.
- *  Instead, reports on the link itself.
+ *  Like File#stat, but does not follow the last symbolic link;
+ *  instead, returns a File::Stat object for the link itself:
+ *
+ *    File.symlink('t.txt', 'symlink')
+ *    f = File.new('symlink')
+ *    f.stat.size  # => 47
+ *    f.lstat.size # => 11
  *
- *     File.symlink("testfile", "link2test")   #=> 0
- *     File.stat("testfile").size              #=> 66
- *     f = File.new("link2test")
- *     f.lstat.size                            #=> 8
- *     f.stat.size                             #=> 66
  */
 
 static VALUE
@@ -1436,7 +1442,7 @@ rb_file_lstat(VALUE obj)
     if (NIL_P(fptr->pathv)) return Qnil;
     path = rb_str_encode_ospath(fptr->pathv);
     if (lstat_without_gvl(RSTRING_PTR(path), &st) == -1) {
-	rb_sys_fail_path(fptr->pathv);
+        rb_sys_fail_path(fptr->pathv);
     }
     return rb_stat_new(&st);
 #else
@@ -1457,19 +1463,19 @@ rb_group_member(GETGROUPS_T gid)
     int anum = -1;
 
     if (getgid() == gid || getegid() == gid)
-	return TRUE;
+        return TRUE;
 
     groups = getgroups(0, NULL);
     gary = ALLOCV_N(GETGROUPS_T, v, groups);
     anum = getgroups(groups, gary);
     while (--anum >= 0) {
-	if (gary[anum] == gid) {
-	    rv = TRUE;
-	    break;
-	}
+        if (gary[anum] == gid) {
+            rv = TRUE;
+            break;
+        }
     }
     if (v)
-	ALLOCV_END(v);
+        ALLOCV_END(v);
 
     return rv;
 #endif
@@ -1495,28 +1501,28 @@ eaccess(const char *path, int mode)
 
     /* no setuid nor setgid. run shortcut. */
     if (getuid() == euid && getgid() == getegid())
-	return access(path, mode);
+        return access(path, mode);
 
     if (STAT(path, &st) < 0)
-	return -1;
+        return -1;
 
     if (euid == 0) {
-	/* Root can read or write any file. */
-	if (!(mode & X_OK))
-	    return 0;
+        /* Root can read or write any file. */
+        if (!(mode & X_OK))
+            return 0;
 
-	/* Root can execute any file that has any one of the execute
-	   bits set. */
-	if (st.st_mode & S_IXUGO)
-	    return 0;
+        /* Root can execute any file that has any one of the execute
+           bits set. */
+        if (st.st_mode & S_IXUGO)
+            return 0;
 
-	return -1;
+        return -1;
     }
 
     if (st.st_uid == euid)        /* owner */
-	mode <<= 6;
+        mode <<= 6;
     else if (rb_group_member(st.st_gid))
-	mode <<= 3;
+        mode <<= 3;
 
     if ((int)(st.st_mode & mode) == mode) return 0;
 
@@ -1551,7 +1557,7 @@ rb_eaccess(VALUE fname, int mode)
     aa.mode = mode;
 
     return (int)(VALUE)rb_thread_call_without_gvl(nogvl_eaccess, &aa,
-						RUBY_UBF_IO, 0);
+                                                RUBY_UBF_IO, 0);
 }
 
 static void *
@@ -1573,7 +1579,7 @@ rb_access(VALUE fname, int mode)
     aa.mode = mode;
 
     return (int)(VALUE)rb_thread_call_without_gvl(nogvl_access, &aa,
-						RUBY_UBF_IO, 0);
+                                                RUBY_UBF_IO, 0);
 }
 
 /*
@@ -1590,15 +1596,20 @@ rb_access(VALUE fname, int mode)
  * Document-method: directory?
  *
  * call-seq:
- *   File.directory?(file_name)   ->  true or false
+ *   File.directory?(path) -> true or false
  *
- * Returns <code>true</code> if the named file is a directory,
- * or a symlink that points at a directory, and <code>false</code>
- * otherwise.
+ * With string +object+ given, returns +true+ if +path+ is a string path
+ * leading to a directory, or to a symbolic link to a directory; +false+ otherwise:
  *
- * _file_name_ can be an IO object.
+ *   File.directory?('.')              # => true
+ *   File.directory?('foo')            # => false
+ *   File.symlink('.', 'dirlink')      # => 0
+ *   File.directory?('dirlink')        # => true
+ *   File.symlink('t,txt', 'filelink') # => 0
+ *   File.directory?('filelink')       # => false
+ *
+ * Argument +path+ can be an IO object.
  *
- *    File.directory?(".")
  */
 
 VALUE
@@ -1617,11 +1628,14 @@ rb_file_directory_p(VALUE obj, VALUE fname)
 
 /*
  * call-seq:
- *   File.pipe?(file_name)   ->  true or false
+ *   File.pipe?(filepath) -> true or false
  *
- * Returns <code>true</code> if the named file is a pipe.
+ * Returns +true+ if +filepath+ points to a pipe, +false+ otherwise:
+ *
+ *   File.mkfifo('tmp/fifo')
+ *   File.pipe?('tmp/fifo') # => true
+ *   File.pipe?('t.txt')    # => false
  *
- * _file_name_ can be an IO object.
  */
 
 static VALUE
@@ -1643,9 +1657,14 @@ rb_file_pipe_p(VALUE obj, VALUE fname)
 
 /*
  * call-seq:
- *   File.symlink?(file_name)   ->  true or false
+ *   File.symlink?(filepath) -> true or false
+ *
+ * Returns +true+ if +filepath+ points to a symbolic link, +false+ otherwise:
+ *
+ *   symlink = File.symlink('t.txt', 'symlink')
+ *   File.symlink?('symlink') # => true
+ *   File.symlink?('t.txt')   # => false
  *
- * Returns <code>true</code> if the named file is a symbolic link.
  */
 
 static VALUE
@@ -1679,11 +1698,14 @@ rb_file_symlink_p(VALUE obj, VALUE fname)
 
 /*
  * call-seq:
- *   File.socket?(file_name)   ->  true or false
+ *   File.socket?(filepath)   ->  true or false
  *
- * Returns <code>true</code> if the named file is a socket.
+ * Returns +true+ if +filepath+ points to a socket, +false+ otherwise:
+ *
+ *   require 'socket'
+ *   File.socket?(Socket.new(:INET, :STREAM)) # => true
+ *   File.socket?(File.new('t.txt'))          # => false
  *
- * _file_name_ can be an IO object.
  */
 
 static VALUE
@@ -1708,18 +1730,20 @@ rb_file_socket_p(VALUE obj, VALUE fname)
 
     if (rb_stat(fname, &st) < 0) return Qfalse;
     if (S_ISSOCK(st.st_mode)) return Qtrue;
-
 #endif
+
     return Qfalse;
 }
 
 /*
  * call-seq:
- *   File.blockdev?(file_name)   ->  true or false
+ *   File.blockdev?(filepath) -> true or false
  *
- * Returns <code>true</code> if the named file is a block device.
+ * Returns +true+ if +filepath+ points to a block device, +false+ otherwise:
+ *
+ *   File.blockdev?('/dev/sda1')       # => true
+ *   File.blockdev?(File.new('t.tmp')) # => false
  *
- * _file_name_ can be an IO object.
  */
 
 static VALUE
@@ -1745,11 +1769,13 @@ rb_file_blockdev_p(VALUE obj, VALUE fname)
 
 /*
  * call-seq:
- *   File.chardev?(file_name)   ->  true or false
+ *   File.chardev?(filepath) -> true or false
  *
- * Returns <code>true</code> if the named file is a character device.
+ * Returns +true+ if +filepath+ points to a character device, +false+ otherwise.
+ *
+  *  File.chardev?($stdin)     # => true
+ *   File.chardev?('t.txt')     # => false
  *
- * _file_name_ can be an IO object.
  */
 static VALUE
 rb_file_chardev_p(VALUE obj, VALUE fname)
@@ -1852,7 +1878,7 @@ rb_file_world_readable_p(VALUE obj, VALUE fname)
 
     if (rb_stat(fname, &st) < 0) return Qnil;
     if ((st.st_mode & (S_IROTH)) == S_IROTH) {
-	return UINT2NUM(st.st_mode & (S_IRUGO|S_IWUGO|S_IXUGO));
+        return UINT2NUM(st.st_mode & (S_IRUGO|S_IWUGO|S_IXUGO));
     }
 #endif
     return Qnil;
@@ -1916,7 +1942,7 @@ rb_file_world_writable_p(VALUE obj, VALUE fname)
 
     if (rb_stat(fname, &st) < 0) return Qnil;
     if ((st.st_mode & (S_IWOTH)) == S_IWOTH) {
-	return UINT2NUM(st.st_mode & (S_IRUGO|S_IWUGO|S_IXUGO));
+        return UINT2NUM(st.st_mode & (S_IRUGO|S_IWUGO|S_IXUGO));
     }
 #endif
     return Qnil;
@@ -2144,7 +2170,7 @@ rb_file_sticky_p(VALUE obj, VALUE fname)
 #ifdef S_ISVTX
     return check3rdbyte(fname, S_ISVTX);
 #else
-    return Qnil;
+    return Qfalse;
 #endif
 }
 
@@ -2199,9 +2225,9 @@ rb_file_s_size(VALUE klass, VALUE fname)
     struct stat st;
 
     if (rb_stat(fname, &st) < 0) {
-	int e = errno;
-	FilePathValue(fname);
-	rb_syserr_fail_path(e, fname);
+        int e = errno;
+        FilePathValue(fname);
+        rb_syserr_fail_path(e, fname);
     }
     return OFFT2NUM(st.st_size);
 }
@@ -2212,36 +2238,36 @@ rb_file_ftype(const struct stat *st)
     const char *t;
 
     if (S_ISREG(st->st_mode)) {
-	t = "file";
+        t = "file";
     }
     else if (S_ISDIR(st->st_mode)) {
-	t = "directory";
+        t = "directory";
     }
     else if (S_ISCHR(st->st_mode)) {
-	t = "characterSpecial";
+        t = "characterSpecial";
     }
 #ifdef S_ISBLK
     else if (S_ISBLK(st->st_mode)) {
-	t = "blockSpecial";
+        t = "blockSpecial";
     }
 #endif
 #ifdef S_ISFIFO
     else if (S_ISFIFO(st->st_mode)) {
-	t = "fifo";
+        t = "fifo";
     }
 #endif
 #ifdef S_ISLNK
     else if (S_ISLNK(st->st_mode)) {
-	t = "link";
+        t = "link";
     }
 #endif
 #ifdef S_ISSOCK
     else if (S_ISSOCK(st->st_mode)) {
-	t = "socket";
+        t = "socket";
     }
 #endif
     else {
-	t = "unknown";
+        t = "unknown";
     }
 
     return rb_usascii_str_new2(t);
@@ -2270,7 +2296,7 @@ rb_file_s_ftype(VALUE klass, VALUE fname)
     FilePathValue(fname);
     fname = rb_str_encode_ospath(fname);
     if (lstat_without_gvl(StringValueCStr(fname), &st) == -1) {
-	rb_sys_fail_path(fname);
+        rb_sys_fail_path(fname);
     }
 
     return rb_file_ftype(&st);
@@ -2294,9 +2320,9 @@ rb_file_s_atime(VALUE klass, VALUE fname)
     struct stat st;
 
     if (rb_stat(fname, &st) < 0) {
-	int e = errno;
-	FilePathValue(fname);
-	rb_syserr_fail_path(e, fname);
+        int e = errno;
+        FilePathValue(fname);
+        rb_syserr_fail_path(e, fname);
     }
     return stat_atime(&st);
 }
@@ -2320,7 +2346,7 @@ rb_file_atime(VALUE obj)
 
     GetOpenFile(obj, fptr);
     if (fstat(fptr->fd, &st) == -1) {
-	rb_sys_fail_path(fptr->pathv);
+        rb_sys_fail_path(fptr->pathv);
     }
     return stat_atime(&st);
 }
@@ -2343,9 +2369,9 @@ rb_file_s_mtime(VALUE klass, VALUE fname)
     struct stat st;
 
     if (rb_stat(fname, &st) < 0) {
-	int e = errno;
-	FilePathValue(fname);
-	rb_syserr_fail_path(e, fname);
+        int e = errno;
+        FilePathValue(fname);
+        rb_syserr_fail_path(e, fname);
     }
     return stat_mtime(&st);
 }
@@ -2368,7 +2394,7 @@ rb_file_mtime(VALUE obj)
 
     GetOpenFile(obj, fptr);
     if (fstat(fptr->fd, &st) == -1) {
-	rb_sys_fail_path(fptr->pathv);
+        rb_sys_fail_path(fptr->pathv);
     }
     return stat_mtime(&st);
 }
@@ -2395,9 +2421,9 @@ rb_file_s_ctime(VALUE klass, VALUE fname)
     struct stat st;
 
     if (rb_stat(fname, &st) < 0) {
-	int e = errno;
-	FilePathValue(fname);
-	rb_syserr_fail_path(e, fname);
+        int e = errno;
+        FilePathValue(fname);
+        rb_syserr_fail_path(e, fname);
     }
     return stat_ctime(&st);
 }
@@ -2423,7 +2449,7 @@ rb_file_ctime(VALUE obj)
 
     GetOpenFile(obj, fptr);
     if (fstat(fptr->fd, &st) == -1) {
-	rb_sys_fail_path(fptr->pathv);
+        rb_sys_fail_path(fptr->pathv);
     }
     return stat_ctime(&st);
 }
@@ -2449,9 +2475,9 @@ rb_file_s_birthtime(VALUE klass, VALUE fname)
     statx_data st;
 
     if (rb_statx(fname, &st, STATX_BTIME) < 0) {
-	int e = errno;
-	FilePathValue(fname);
-	rb_syserr_fail_path(e, fname);
+        int e = errno;
+        FilePathValue(fname);
+        rb_syserr_fail_path(e, fname);
     }
     return statx_birthtime(&st, fname);
 }
@@ -2480,7 +2506,7 @@ rb_file_birthtime(VALUE obj)
 
     GetOpenFile(obj, fptr);
     if (fstatx_without_gvl(fptr->fd, &st, STATX_BTIME) == -1) {
-	rb_sys_fail_path(fptr->pathv);
+        rb_sys_fail_path(fptr->pathv);
     }
     return statx_birthtime(&st, fptr->pathv);
 }
@@ -2498,7 +2524,7 @@ rb_file_birthtime(VALUE obj)
  *
  */
 
-off_t
+rb_off_t
 rb_file_size(VALUE file)
 {
     if (RB_TYPE_P(file, T_FILE)) {
@@ -2584,18 +2610,18 @@ rb_file_chmod(VALUE obj, VALUE vmode)
     GetOpenFile(obj, fptr);
 #ifdef HAVE_FCHMOD
     if (fchmod(fptr->fd, mode) == -1) {
-	if (HAVE_FCHMOD || errno != ENOSYS)
-	    rb_sys_fail_path(fptr->pathv);
+        if (HAVE_FCHMOD || errno != ENOSYS)
+            rb_sys_fail_path(fptr->pathv);
     }
     else {
-	if (!HAVE_FCHMOD) return INT2FIX(0);
+        if (!HAVE_FCHMOD) return INT2FIX(0);
     }
 #endif
 #if !defined HAVE_FCHMOD || !HAVE_FCHMOD
     if (NIL_P(fptr->pathv)) return Qnil;
     path = rb_str_encode_ospath(fptr->pathv);
     if (chmod(RSTRING_PTR(path), mode) == -1)
-	rb_sys_fail_path(fptr->pathv);
+        rb_sys_fail_path(fptr->pathv);
 #endif
 
     return INT2FIX(0);
@@ -2636,7 +2662,7 @@ static inline rb_uid_t
 to_uid(VALUE u)
 {
     if (NIL_P(u)) {
-	return (rb_uid_t)-1;
+        return (rb_uid_t)-1;
     }
     return NUM2UIDT(u);
 }
@@ -2645,7 +2671,7 @@ static inline rb_gid_t
 to_gid(VALUE g)
 {
     if (NIL_P(g)) {
-	return (rb_gid_t)-1;
+        return (rb_gid_t)-1;
     }
     return NUM2GIDT(g);
 }
@@ -2721,10 +2747,10 @@ rb_file_chown(VALUE obj, VALUE owner, VALUE group)
     if (NIL_P(fptr->pathv)) return Qnil;
     path = rb_str_encode_ospath(fptr->pathv);
     if (chown(RSTRING_PTR(path), o, g) == -1)
-	rb_sys_fail_path(fptr->pathv);
+        rb_sys_fail_path(fptr->pathv);
 #else
     if (fchown(fptr->fd, o, g) == -1)
-	rb_sys_fail_path(fptr->pathv);
+        rb_sys_fail_path(fptr->pathv);
 #endif
 
     return INT2FIX(0);
@@ -2781,32 +2807,32 @@ utime_failed(struct apply_arg *aa)
     struct utime_args *ua = aa->arg;
 
     if (ua->tsp && e == EINVAL) {
-	VALUE e[2], a = Qnil, m = Qnil;
-	int d = 0;
-	VALUE atime = ua->atime;
-	VALUE mtime = ua->mtime;
-
-	if (!NIL_P(atime)) {
-	    a = rb_inspect(atime);
-	}
-	if (!NIL_P(mtime) && mtime != atime && !rb_equal(atime, mtime)) {
-	    m = rb_inspect(mtime);
-	}
-	if (NIL_P(a)) e[0] = m;
-	else if (NIL_P(m) || rb_str_cmp(a, m) == 0) e[0] = a;
-	else {
-	    e[0] = rb_str_plus(a, rb_str_new_cstr(" or "));
-	    rb_str_append(e[0], m);
-	    d = 1;
-	}
-	if (!NIL_P(e[0])) {
-	    if (path) {
-		if (!d) e[0] = rb_str_dup(e[0]);
-		rb_str_append(rb_str_cat2(e[0], " for "), path);
-	    }
-	    e[1] = INT2FIX(EINVAL);
-	    rb_exc_raise(rb_class_new_instance(2, e, rb_eSystemCallError));
-	}
+        VALUE e[2], a = Qnil, m = Qnil;
+        int d = 0;
+        VALUE atime = ua->atime;
+        VALUE mtime = ua->mtime;
+
+        if (!NIL_P(atime)) {
+            a = rb_inspect(atime);
+        }
+        if (!NIL_P(mtime) && mtime != atime && !rb_equal(atime, mtime)) {
+            m = rb_inspect(mtime);
+        }
+        if (NIL_P(a)) e[0] = m;
+        else if (NIL_P(m) || rb_str_cmp(a, m) == 0) e[0] = a;
+        else {
+            e[0] = rb_str_plus(a, rb_str_new_cstr(" or "));
+            rb_str_append(e[0], m);
+            d = 1;
+        }
+        if (!NIL_P(e[0])) {
+            if (path) {
+                if (!d) e[0] = rb_str_dup(e[0]);
+                rb_str_append(rb_str_cat2(e[0], " for "), path);
+            }
+            e[1] = INT2FIX(EINVAL);
+            rb_exc_raise(rb_class_new_instance(2, e, rb_eSystemCallError));
+        }
     }
     rb_syserr_fail_path(e, path);
 }
@@ -2814,6 +2840,29 @@ utime_failed(struct apply_arg *aa)
 
 #if defined(HAVE_UTIMES)
 
+# if !defined(HAVE_UTIMENSAT)
+/* utimensat() is not found, runtime check is not needed */
+# elif defined(__APPLE__) && \
+    (!defined(MAC_OS_X_VERSION_13_0) || (MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_X_VERSION_13_0))
+
+#   if defined(__has_attribute) && __has_attribute(availability)
+typedef int utimensat_func(int, const char *, const struct timespec [2], int);
+
+RBIMPL_WARNING_PUSH()
+RBIMPL_WARNING_IGNORED(-Wunguarded-availability-new)
+static inline utimensat_func *
+rb_utimensat(void)
+{
+    return &utimensat;
+}
+RBIMPL_WARNING_POP()
+
+#   define utimensat rb_utimensat()
+#   else /* __API_AVAILABLE macro does nothing on gcc */
+__attribute__((weak)) int utimensat(int, const char *, const struct timespec [2], int);
+#   endif
+# endif
+
 static int
 utime_internal(const char *path, void *arg)
 {
@@ -2822,35 +2871,40 @@ utime_internal(const char *path, void *arg)
     struct timeval tvbuf[2], *tvp = NULL;
 
 #if defined(HAVE_UTIMENSAT)
+# if defined(__APPLE__)
+    const int try_utimensat = utimensat != NULL;
+    const int try_utimensat_follow = utimensat != NULL;
+# else
+#   define TRY_UTIMENSAT 1
     static int try_utimensat = 1;
 # ifdef AT_SYMLINK_NOFOLLOW
     static int try_utimensat_follow = 1;
 # else
     const int try_utimensat_follow = 0;
 # endif
+# endif
     int flags = 0;
 
     if (v->follow ? try_utimensat_follow : try_utimensat) {
 # ifdef AT_SYMLINK_NOFOLLOW
-	if (v->follow) {
-	    flags = AT_SYMLINK_NOFOLLOW;
-	}
+        if (v->follow) {
+            flags = AT_SYMLINK_NOFOLLOW;
+        }
 # endif
 
-	if (utimensat(AT_FDCWD, path, tsp, flags) < 0) {
-            if (errno == ENOSYS) {
+        int result = utimensat(AT_FDCWD, path, tsp, flags);
+# ifdef TRY_UTIMENSAT
+        if (result < 0 && errno == ENOSYS) {
 # ifdef AT_SYMLINK_NOFOLLOW
-		try_utimensat_follow = 0;
+            try_utimensat_follow = 0;
 # endif
-		if (!v->follow)
-		    try_utimensat = 0;
-                goto no_utimensat;
-            }
-            return -1; /* calls utime_failed */
+            if (!v->follow)
+                try_utimensat = 0;
         }
-        return 0;
+        else
+# endif
+            return result;
     }
-no_utimensat:
 #endif
 
     if (tsp) {
@@ -2904,12 +2958,12 @@ utime_internal_i(int argc, VALUE *argv, int follow)
     args.follow = follow;
 
     if (!NIL_P(args.atime) || !NIL_P(args.mtime)) {
-	tsp = tss;
-	tsp[0] = rb_time_timespec(args.atime);
-	if (args.atime == args.mtime)
-	    tsp[1] = tsp[0];
-	else
-	    tsp[1] = rb_time_timespec(args.mtime);
+        tsp = tss;
+        tsp[0] = rb_time_timespec(args.atime);
+        if (args.atime == args.mtime)
+            tsp[1] = tsp[0];
+        else
+            tsp[1] = rb_time_timespec(args.mtime);
     }
     args.tsp = tsp;
 
@@ -2973,7 +3027,7 @@ syserr_fail2_in(const char *func, int e, VALUE s1, VALUE s2)
 #endif
 
     if (e == EEXIST) {
-	rb_syserr_fail_path(e, rb_str_ellipsize(s2, max_pathlen));
+        rb_syserr_fail_path(e, rb_str_ellipsize(s2, max_pathlen));
     }
     str = rb_str_new_cstr("(");
     rb_str_append(str, rb_str_ellipsize(s1, max_pathlen));
@@ -3009,7 +3063,7 @@ rb_file_s_link(VALUE klass, VALUE from, VALUE to)
     to = rb_str_encode_ospath(to);
 
     if (link(StringValueCStr(from), StringValueCStr(to)) < 0) {
-	sys_fail2(from, to);
+        sys_fail2(from, to);
     }
     return INT2FIX(0);
 }
@@ -3039,7 +3093,7 @@ rb_file_s_symlink(VALUE klass, VALUE from, VALUE to)
     to = rb_str_encode_ospath(to);
 
     if (symlink(StringValueCStr(from), StringValueCStr(to)) < 0) {
-	sys_fail2(from, to);
+        sys_fail2(from, to);
     }
     return INT2FIX(0);
 }
@@ -3065,7 +3119,6 @@ rb_file_s_readlink(VALUE klass, VALUE path)
     return rb_readlink(path, rb_filesystem_encoding());
 }
 
-#ifndef _WIN32
 struct readlink_arg {
     const char *path;
     char *buf;
@@ -3090,7 +3143,7 @@ readlink_without_gvl(VALUE path, VALUE buf, size_t size)
     ra.size = size;
 
     return (ssize_t)rb_thread_call_without_gvl(nogvl_readlink, &ra,
-						RUBY_UBF_IO, 0);
+                                                RUBY_UBF_IO, 0);
 }
 
 VALUE
@@ -3105,23 +3158,22 @@ rb_readlink(VALUE path, rb_encoding *enc)
     v = rb_enc_str_new(0, size, enc);
     while ((rv = readlink_without_gvl(path, v, size)) == size
 #ifdef _AIX
-	    || (rv < 0 && errno == ERANGE) /* quirky behavior of GPFS */
+            || (rv < 0 && errno == ERANGE) /* quirky behavior of GPFS */
 #endif
-	) {
-	rb_str_modify_expand(v, size);
-	size *= 2;
-	rb_str_set_len(v, size);
+        ) {
+        rb_str_modify_expand(v, size);
+        size *= 2;
+        rb_str_set_len(v, size);
     }
     if (rv < 0) {
-	int e = errno;
-	rb_str_resize(v, 0);
-	rb_syserr_fail_path(e, path);
+        int e = errno;
+        rb_str_resize(v, 0);
+        rb_syserr_fail_path(e, path);
     }
     rb_str_resize(v, rv);
 
     return v;
 }
-#endif
 #else
 #define rb_file_s_readlink rb_f_notimplement
 #endif
@@ -3193,18 +3245,18 @@ rb_file_s_rename(VALUE klass, VALUE from, VALUE to)
     errno = 0;
 #endif
     if ((int)(VALUE)rb_thread_call_without_gvl(no_gvl_rename, &ra,
-					 RUBY_UBF_IO, 0) < 0) {
-	int e = errno;
+                                         RUBY_UBF_IO, 0) < 0) {
+        int e = errno;
 #if defined DOSISH
-	switch (e) {
-	  case EEXIST:
-	    if (chmod(ra.dst, 0666) == 0 &&
-		unlink(ra.dst) == 0 &&
-		rename(ra.src, ra.dst) == 0)
-		return INT2FIX(0);
-	}
+        switch (e) {
+          case EEXIST:
+            if (chmod(ra.dst, 0666) == 0 &&
+                unlink(ra.dst) == 0 &&
+                rename(ra.src, ra.dst) == 0)
+                return INT2FIX(0);
+        }
 #endif
-	syserr_fail2(e, from, to);
+        syserr_fail2(e, from, to);
     }
 
     return INT2FIX(0);
@@ -3232,11 +3284,11 @@ rb_file_s_umask(int argc, VALUE *argv, VALUE _)
 
     switch (argc) {
       case 0:
-	omask = umask(0);
-	umask(omask);
+        omask = umask(0);
+        umask(omask);
         break;
       case 1:
-	omask = umask(NUM2MODET(argv[0]));
+        omask = umask(NUM2MODET(argv[0]));
         break;
       default:
         rb_error_arity(argc, 0, 1);
@@ -3301,10 +3353,10 @@ static inline int
 has_drive_letter(const char *buf)
 {
     if (ISALPHA(buf[0]) && buf[1] == ':') {
-	return 1;
+        return 1;
     }
     else {
-	return 0;
+        return 0;
     }
 }
 
@@ -3325,13 +3377,13 @@ getcwdofdrv(int drv)
     */
     oldcwd = ruby_getcwd();
     if (chdir(drive) == 0) {
-	drvcwd = ruby_getcwd();
-	chdir(oldcwd);
-	xfree(oldcwd);
+        drvcwd = ruby_getcwd();
+        chdir(oldcwd);
+        xfree(oldcwd);
     }
     else {
-	/* perhaps the drive is not exist. we return only drive letter */
-	drvcwd = strdup(drive);
+        /* perhaps the drive is not exist. we return only drive letter */
+        drvcwd = strdup(drive);
     }
     return drvcwd;
 }
@@ -3342,10 +3394,10 @@ not_same_drive(VALUE path, int drive)
     const char *p = RSTRING_PTR(path);
     if (RSTRING_LEN(path) < 2) return 0;
     if (has_drive_letter(p)) {
-	return TOLOWER(p[0]) != TOLOWER(drive);
+        return TOLOWER(p[0]) != TOLOWER(drive);
     }
     else {
-	return has_unc(p);
+        return has_unc(p);
     }
 }
 #endif
@@ -3366,7 +3418,7 @@ char *
 rb_enc_path_next(const char *s, const char *e, rb_encoding *enc)
 {
     while (s < e && !isdirsep(*s)) {
-	Inc(s, e, enc);
+        Inc(s, e, enc);
     }
     return (char *)s;
 }
@@ -3382,16 +3434,16 @@ rb_enc_path_skip_prefix(const char *path, const char *end, rb_encoding *enc)
 #if defined(DOSISH_UNC) || defined(DOSISH_DRIVE_LETTER)
 #ifdef DOSISH_UNC
     if (path + 2 <= end && isdirsep(path[0]) && isdirsep(path[1])) {
-	path += 2;
-	while (path < end && isdirsep(*path)) path++;
-	if ((path = rb_enc_path_next(path, end, enc)) < end && path[0] && path[1] && !isdirsep(path[1]))
-	    path = rb_enc_path_next(path + 1, end, enc);
-	return (char *)path;
+        path += 2;
+        while (path < end && isdirsep(*path)) path++;
+        if ((path = rb_enc_path_next(path, end, enc)) < end && path[0] && path[1] && !isdirsep(path[1]))
+            path = rb_enc_path_next(path + 1, end, enc);
+        return (char *)path;
     }
 #endif
 #ifdef DOSISH_DRIVE_LETTER
     if (has_drive_letter(path))
-	return (char *)(path + 2);
+        return (char *)(path + 2);
 #endif
 #endif
     return (char *)path;
@@ -3415,15 +3467,15 @@ rb_enc_path_last_separator(const char *path, const char *end, rb_encoding *enc)
 {
     char *last = NULL;
     while (path < end) {
-	if (isdirsep(*path)) {
-	    const char *tmp = path++;
-	    while (path < end && isdirsep(*path)) path++;
-	    if (path >= end) break;
-	    last = (char *)tmp;
-	}
-	else {
-	    Inc(path, end, enc);
-	}
+        if (isdirsep(*path)) {
+            const char *tmp = path++;
+            while (path < end && isdirsep(*path)) path++;
+            if (path >= end) break;
+            last = (char *)tmp;
+        }
+        else {
+            Inc(path, end, enc);
+        }
     }
     return last;
 }
@@ -3432,14 +3484,14 @@ static char *
 chompdirsep(const char *path, const char *end, rb_encoding *enc)
 {
     while (path < end) {
-	if (isdirsep(*path)) {
-	    const char *last = path++;
-	    while (path < end && isdirsep(*path)) path++;
-	    if (path >= end) return (char *)last;
-	}
-	else {
-	    Inc(path, end, enc);
-	}
+        if (isdirsep(*path)) {
+            const char *last = path++;
+            while (path < end && isdirsep(*path)) path++;
+            if (path >= end) return (char *)last;
+        }
+        else {
+            Inc(path, end, enc);
+        }
     }
     return (char *)path;
 }
@@ -3471,20 +3523,20 @@ ntfs_tail(const char *path, const char *end, rb_encoding *enc)
 {
     while (path < end && *path == '.') path++;
     while (path < end && !isADS(*path)) {
-	if (istrailinggarbage(*path)) {
-	    const char *last = path++;
-	    while (path < end && istrailinggarbage(*path)) path++;
-	    if (path >= end || isADS(*path)) return (char *)last;
-	}
-	else if (isdirsep(*path)) {
-	    const char *last = path++;
-	    while (path < end && isdirsep(*path)) path++;
-	    if (path >= end) return (char *)last;
-	    if (isADS(*path)) path++;
-	}
-	else {
-	    Inc(path, end, enc);
-	}
+        if (istrailinggarbage(*path)) {
+            const char *last = path++;
+            while (path < end && istrailinggarbage(*path)) path++;
+            if (path >= end || isADS(*path)) return (char *)last;
+        }
+        else if (isdirsep(*path)) {
+            const char *last = path++;
+            while (path < end && isdirsep(*path)) path++;
+            if (path >= end) return (char *)last;
+            if (isADS(*path)) path++;
+        }
+        else {
+            Inc(path, end, enc);
+        }
     }
     return (char *)path;
 }
@@ -3493,11 +3545,11 @@ ntfs_tail(const char *path, const char *end, rb_encoding *enc)
 #define BUFCHECK(cond) do {\
     bdiff = p - buf;\
     if (cond) {\
-	do {buflen *= 2;} while (cond);\
-	rb_str_resize(result, buflen);\
-	buf = RSTRING_PTR(result);\
-	p = buf + bdiff;\
-	pend = buf + buflen;\
+        do {buflen *= 2;} while (cond);\
+        rb_str_resize(result, buflen);\
+        buf = RSTRING_PTR(result);\
+        p = buf + bdiff;\
+        pend = buf + buflen;\
     }\
 } while (0)
 
@@ -3546,9 +3598,9 @@ copy_home_path(VALUE result, const char *dir)
 #if defined DOSISH || defined __CYGWIN__
     enc = rb_enc_from_index(encidx);
     for (bend = (p = buf) + dirlen; p < bend; Inc(p, bend, enc)) {
-	if (*p == '\\') {
-	    *p = '/';
-	}
+        if (*p == '\\') {
+            *p = '/';
+        }
     }
 #endif
     return result;
@@ -3579,11 +3631,11 @@ rb_home_dir_of(VALUE user, VALUE result)
     pwPtr = getpwnam(username);
 #else
     if (strcasecmp(username, getlogin()) == 0)
-	dir = pwPtr = getenv("HOME");
+        dir = pwPtr = getenv("HOME");
 #endif
     if (!pwPtr) {
-	endpwent();
-	rb_raise(rb_eArgError, "user %"PRIsVALUE" doesn't exist", user);
+        endpwent();
+        rb_raise(rb_eArgError, "user %"PRIsVALUE" doesn't exist", user);
     }
 #ifdef HAVE_PWD_H
     dir = pwPtr->pw_dir;
@@ -3640,7 +3692,7 @@ rb_default_home_dir(VALUE result)
     }
 #endif
     if (!dir) {
-	rb_raise(rb_eArgError, "couldn't find HOME environment -- expanding `~'");
+        rb_raise(rb_eArgError, "couldn't find HOME environment -- expanding `~'");
     }
     return copy_home_path(result, dir);
 }
@@ -3665,15 +3717,15 @@ append_fspath(VALUE result, VALUE fname, char *dir, rb_encoding **enc, rb_encodi
     size_t dirlen = strlen(dir), buflen = rb_str_capacity(result);
 
     if (NORMALIZE_UTF8PATH || *enc != fsenc) {
-	rb_encoding *direnc = fs_enc_check(fname, dirname = ospath_new(dir, dirlen, fsenc));
-	if (direnc != fsenc) {
-	    dirname = rb_str_conv_enc(dirname, fsenc, direnc);
-	    RSTRING_GETMEM(dirname, cwdp, dirlen);
-	}
-	else if (NORMALIZE_UTF8PATH) {
-	    RSTRING_GETMEM(dirname, cwdp, dirlen);
-	}
-	*enc = direnc;
+        rb_encoding *direnc = fs_enc_check(fname, dirname = ospath_new(dir, dirlen, fsenc));
+        if (direnc != fsenc) {
+            dirname = rb_str_conv_enc(dirname, fsenc, direnc);
+            RSTRING_GETMEM(dirname, cwdp, dirlen);
+        }
+        else if (NORMALIZE_UTF8PATH) {
+            RSTRING_GETMEM(dirname, cwdp, dirlen);
+        }
+        *enc = direnc;
     }
     do {buflen *= 2;} while (dirlen > buflen);
     rb_str_resize(result, buflen);
@@ -3699,115 +3751,115 @@ rb_file_expand_path_internal(VALUE fname, VALUE dname, int abs_mode, int long_na
     BUFINIT();
 
     if (s[0] == '~' && abs_mode == 0) {      /* execute only if NOT absolute_path() */
-	long userlen = 0;
-	if (isdirsep(s[1]) || s[1] == '\0') {
-	    buf = 0;
-	    b = 0;
-	    rb_str_set_len(result, 0);
-	    if (*++s) ++s;
-	    rb_default_home_dir(result);
-	}
-	else {
-	    s = nextdirsep(b = s, fend, enc);
-	    b++; /* b[0] is '~' */
-	    userlen = s - b;
-	    BUFCHECK(bdiff + userlen >= buflen);
-	    memcpy(p, b, userlen);
-	    ENC_CODERANGE_CLEAR(result);
-	    rb_str_set_len(result, userlen);
-	    rb_enc_associate(result, enc);
-	    rb_home_dir_of(result, result);
-	    buf = p + 1;
-	    p += userlen;
-	}
-	if (!rb_is_absolute_path(RSTRING_PTR(result))) {
-	    if (userlen) {
-		rb_enc_raise(enc, rb_eArgError, "non-absolute home of %.*s%.0"PRIsVALUE,
-			     (int)userlen, b, fname);
-	    }
-	    else {
-		rb_raise(rb_eArgError, "non-absolute home");
-	    }
-	}
-	BUFINIT();
-	p = pend;
+        long userlen = 0;
+        if (isdirsep(s[1]) || s[1] == '\0') {
+            buf = 0;
+            b = 0;
+            rb_str_set_len(result, 0);
+            if (*++s) ++s;
+            rb_default_home_dir(result);
+        }
+        else {
+            s = nextdirsep(b = s, fend, enc);
+            b++; /* b[0] is '~' */
+            userlen = s - b;
+            BUFCHECK(bdiff + userlen >= buflen);
+            memcpy(p, b, userlen);
+            ENC_CODERANGE_CLEAR(result);
+            rb_str_set_len(result, userlen);
+            rb_enc_associate(result, enc);
+            rb_home_dir_of(result, result);
+            buf = p + 1;
+            p += userlen;
+        }
+        if (!rb_is_absolute_path(RSTRING_PTR(result))) {
+            if (userlen) {
+                rb_enc_raise(enc, rb_eArgError, "non-absolute home of %.*s%.0"PRIsVALUE,
+                             (int)userlen, b, fname);
+            }
+            else {
+                rb_raise(rb_eArgError, "non-absolute home");
+            }
+        }
+        BUFINIT();
+        p = pend;
     }
 #ifdef DOSISH_DRIVE_LETTER
     /* skip drive letter */
     else if (has_drive_letter(s)) {
-	if (isdirsep(s[2])) {
-	    /* specified drive letter, and full path */
-	    /* skip drive letter */
-	    BUFCHECK(bdiff + 2 >= buflen);
-	    memcpy(p, s, 2);
-	    p += 2;
-	    s += 2;
-	    rb_enc_copy(result, fname);
-	}
-	else {
-	    /* specified drive, but not full path */
-	    int same = 0;
-	    if (!NIL_P(dname) && !not_same_drive(dname, s[0])) {
-		rb_file_expand_path_internal(dname, Qnil, abs_mode, long_name, result);
-		BUFINIT();
-		if (has_drive_letter(p) && TOLOWER(p[0]) == TOLOWER(s[0])) {
-		    /* ok, same drive */
-		    same = 1;
-		}
-	    }
-	    if (!same) {
-		char *e = append_fspath(result, fname, getcwdofdrv(*s), &enc, fsenc);
-		BUFINIT();
-		p = e;
-	    }
-	    else {
-		rb_enc_associate(result, enc = fs_enc_check(result, fname));
-		p = pend;
-	    }
-	    p = chompdirsep(skiproot(buf, p, enc), p, enc);
-	    s += 2;
-	}
+        if (isdirsep(s[2])) {
+            /* specified drive letter, and full path */
+            /* skip drive letter */
+            BUFCHECK(bdiff + 2 >= buflen);
+            memcpy(p, s, 2);
+            p += 2;
+            s += 2;
+            rb_enc_copy(result, fname);
+        }
+        else {
+            /* specified drive, but not full path */
+            int same = 0;
+            if (!NIL_P(dname) && !not_same_drive(dname, s[0])) {
+                rb_file_expand_path_internal(dname, Qnil, abs_mode, long_name, result);
+                BUFINIT();
+                if (has_drive_letter(p) && TOLOWER(p[0]) == TOLOWER(s[0])) {
+                    /* ok, same drive */
+                    same = 1;
+                }
+            }
+            if (!same) {
+                char *e = append_fspath(result, fname, getcwdofdrv(*s), &enc, fsenc);
+                BUFINIT();
+                p = e;
+            }
+            else {
+                rb_enc_associate(result, enc = fs_enc_check(result, fname));
+                p = pend;
+            }
+            p = chompdirsep(skiproot(buf, p, enc), p, enc);
+            s += 2;
+        }
     }
 #endif
     else if (!rb_is_absolute_path(s)) {
-	if (!NIL_P(dname)) {
-	    rb_file_expand_path_internal(dname, Qnil, abs_mode, long_name, result);
-	    rb_enc_associate(result, fs_enc_check(result, fname));
-	    BUFINIT();
-	    p = pend;
-	}
-	else {
-	    char *e = append_fspath(result, fname, ruby_getcwd(), &enc, fsenc);
-	    BUFINIT();
-	    p = e;
-	}
+        if (!NIL_P(dname)) {
+            rb_file_expand_path_internal(dname, Qnil, abs_mode, long_name, result);
+            rb_enc_associate(result, fs_enc_check(result, fname));
+            BUFINIT();
+            p = pend;
+        }
+        else {
+            char *e = append_fspath(result, fname, ruby_getcwd(), &enc, fsenc);
+            BUFINIT();
+            p = e;
+        }
 #if defined DOSISH || defined __CYGWIN__
-	if (isdirsep(*s)) {
-	    /* specified full path, but not drive letter nor UNC */
-	    /* we need to get the drive letter or UNC share name */
-	    p = skipprefix(buf, p, enc);
-	}
-	else
+        if (isdirsep(*s)) {
+            /* specified full path, but not drive letter nor UNC */
+            /* we need to get the drive letter or UNC share name */
+            p = skipprefix(buf, p, enc);
+        }
+        else
 #endif
-	    p = chompdirsep(skiproot(buf, p, enc), p, enc);
+            p = chompdirsep(skiproot(buf, p, enc), p, enc);
     }
     else {
-	size_t len;
-	b = s;
-	do s++; while (isdirsep(*s));
-	len = s - b;
-	p = buf + len;
-	BUFCHECK(bdiff >= buflen);
-	memset(buf, '/', len);
-	rb_str_set_len(result, len);
-	rb_enc_associate(result, fs_enc_check(result, fname));
+        size_t len;
+        b = s;
+        do s++; while (isdirsep(*s));
+        len = s - b;
+        p = buf + len;
+        BUFCHECK(bdiff >= buflen);
+        memset(buf, '/', len);
+        rb_str_set_len(result, len);
+        rb_enc_associate(result, fs_enc_check(result, fname));
     }
     if (p > buf && p[-1] == '/')
-	--p;
+        --p;
     else {
-	rb_str_set_len(result, p-buf);
-	BUFCHECK(bdiff + 1 >= buflen);
-	*p = '/';
+        rb_str_set_len(result, p-buf);
+        BUFCHECK(bdiff + 1 >= buflen);
+        *p = '/';
     }
 
     rb_str_set_len(result, p-buf+1);
@@ -3817,213 +3869,213 @@ rb_file_expand_path_internal(VALUE fname, VALUE dname, int abs_mode, int long_na
 
     b = s;
     while (*s) {
-	switch (*s) {
-	  case '.':
-	    if (b == s++) {	/* beginning of path element */
-		switch (*s) {
-		  case '\0':
-		    b = s;
-		    break;
-		  case '.':
-		    if (*(s+1) == '\0' || isdirsep(*(s+1))) {
-			/* We must go back to the parent */
-			char *n;
-			*p = '\0';
-			if (!(n = strrdirsep(root, p, enc))) {
-			    *p = '/';
-			}
-			else {
-			    p = n;
-			}
-			b = ++s;
-		    }
+        switch (*s) {
+          case '.':
+            if (b == s++) {	/* beginning of path element */
+                switch (*s) {
+                  case '\0':
+                    b = s;
+                    break;
+                  case '.':
+                    if (*(s+1) == '\0' || isdirsep(*(s+1))) {
+                        /* We must go back to the parent */
+                        char *n;
+                        *p = '\0';
+                        if (!(n = strrdirsep(root, p, enc))) {
+                            *p = '/';
+                        }
+                        else {
+                            p = n;
+                        }
+                        b = ++s;
+                    }
 #if USE_NTFS
-		    else {
-			do ++s; while (istrailinggarbage(*s));
-		    }
+                    else {
+                        do ++s; while (istrailinggarbage(*s));
+                    }
 #endif
-		    break;
-		  case '/':
+                    break;
+                  case '/':
 #if defined DOSISH || defined __CYGWIN__
-		  case '\\':
-#endif
-		    b = ++s;
-		    break;
-		  default:
-		    /* ordinary path element, beginning don't move */
-		    break;
-		}
-	    }
+                  case '\\':
+#endif
+                    b = ++s;
+                    break;
+                  default:
+                    /* ordinary path element, beginning don't move */
+                    break;
+                }
+            }
 #if USE_NTFS
-	    else {
-		--s;
-	      case ' ': {
-		const char *e = s;
-		while (s < fend && istrailinggarbage(*s)) s++;
-		if (s >= fend) {
-		    s = e;
-		    goto endpath;
-		}
-	      }
-	    }
-#endif
-	    break;
-	  case '/':
+            else {
+                --s;
+              case ' ': {
+                const char *e = s;
+                while (s < fend && istrailinggarbage(*s)) s++;
+                if (s >= fend) {
+                    s = e;
+                    goto endpath;
+                }
+              }
+            }
+#endif
+            break;
+          case '/':
 #if defined DOSISH || defined __CYGWIN__
-	  case '\\':
-#endif
-	    if (s > b) {
-		WITH_ROOTDIFF(BUFCOPY(b, s-b));
-		*p = '/';
-	    }
-	    b = ++s;
-	    break;
-	  default:
+          case '\\':
+#endif
+            if (s > b) {
+                WITH_ROOTDIFF(BUFCOPY(b, s-b));
+                *p = '/';
+            }
+            b = ++s;
+            break;
+          default:
 #ifdef __APPLE__
-	    {
-		int n = ignored_char_p(s, fend, enc);
-		if (n) {
-		    if (s > b) {
-			WITH_ROOTDIFF(BUFCOPY(b, s-b));
-			*p = '\0';
-		    }
-		    b = s += n;
-		    break;
-		}
-	    }
-#endif
-	    Inc(s, fend, enc);
-	    break;
-	}
+            {
+                int n = ignored_char_p(s, fend, enc);
+                if (n) {
+                    if (s > b) {
+                        WITH_ROOTDIFF(BUFCOPY(b, s-b));
+                        *p = '\0';
+                    }
+                    b = s += n;
+                    break;
+                }
+            }
+#endif
+            Inc(s, fend, enc);
+            break;
+        }
     }
 
     if (s > b) {
 #if USE_NTFS
 # if USE_NTFS_ADS
-	static const char prime[] = ":$DATA";
-	enum {prime_len = sizeof(prime) -1};
+        static const char prime[] = ":$DATA";
+        enum {prime_len = sizeof(prime) -1};
 # endif
       endpath:
 # if USE_NTFS_ADS
-	if (s > b + prime_len && strncasecmp(s - prime_len, prime, prime_len) == 0) {
-	    /* alias of stream */
-	    /* get rid of a bug of x64 VC++ */
-	    if (isADS(*(s - (prime_len+1)))) {
-		s -= prime_len + 1; /* prime */
-	    }
-	    else if (memchr(b, ':', s - prime_len - b)) {
-		s -= prime_len;	/* alternative */
-	    }
-	}
+        if (s > b + prime_len && strncasecmp(s - prime_len, prime, prime_len) == 0) {
+            /* alias of stream */
+            /* get rid of a bug of x64 VC++ */
+            if (isADS(*(s - (prime_len+1)))) {
+                s -= prime_len + 1; /* prime */
+            }
+            else if (memchr(b, ':', s - prime_len - b)) {
+                s -= prime_len;	/* alternative */
+            }
+        }
 # endif
 #endif
-	BUFCOPY(b, s-b);
-	rb_str_set_len(result, p-buf);
+        BUFCOPY(b, s-b);
+        rb_str_set_len(result, p-buf);
     }
     if (p == skiproot(buf, p + !!*p, enc) - 1) p++;
 
 #if USE_NTFS
     *p = '\0';
     if ((s = strrdirsep(b = buf, p, enc)) != 0 && !strpbrk(s, "*?")) {
-	VALUE tmp, v;
-	size_t len;
-	int encidx;
-	WCHAR *wstr;
-	WIN32_FIND_DATAW wfd;
-	HANDLE h;
+        VALUE tmp, v;
+        size_t len;
+        int encidx;
+        WCHAR *wstr;
+        WIN32_FIND_DATAW wfd;
+        HANDLE h;
 #ifdef __CYGWIN__
 #ifdef HAVE_CYGWIN_CONV_PATH
-	char *w32buf = NULL;
-	const int flags = CCP_POSIX_TO_WIN_A | CCP_RELATIVE;
+        char *w32buf = NULL;
+        const int flags = CCP_POSIX_TO_WIN_A | CCP_RELATIVE;
 #else
-	char w32buf[MAXPATHLEN];
-#endif
-	const char *path;
-	ssize_t bufsize;
-	int lnk_added = 0, is_symlink = 0;
-	struct stat st;
-	p = (char *)s;
-	len = strlen(p);
-	if (lstat_without_gvl(buf, &st) == 0 && S_ISLNK(st.st_mode)) {
-	    is_symlink = 1;
-	    if (len > 4 && STRCASECMP(p + len - 4, ".lnk") != 0) {
-		lnk_added = 1;
-	    }
-	}
-	path = *buf ? buf : "/";
+        char w32buf[MAXPATHLEN];
+#endif
+        const char *path;
+        ssize_t bufsize;
+        int lnk_added = 0, is_symlink = 0;
+        struct stat st;
+        p = (char *)s;
+        len = strlen(p);
+        if (lstat_without_gvl(buf, &st) == 0 && S_ISLNK(st.st_mode)) {
+            is_symlink = 1;
+            if (len > 4 && STRCASECMP(p + len - 4, ".lnk") != 0) {
+                lnk_added = 1;
+            }
+        }
+        path = *buf ? buf : "/";
 #ifdef HAVE_CYGWIN_CONV_PATH
-	bufsize = cygwin_conv_path(flags, path, NULL, 0);
-	if (bufsize > 0) {
-	    bufsize += len;
-	    if (lnk_added) bufsize += 4;
-	    w32buf = ALLOCA_N(char, bufsize);
-	    if (cygwin_conv_path(flags, path, w32buf, bufsize) == 0) {
-		b = w32buf;
-	    }
-	}
+        bufsize = cygwin_conv_path(flags, path, NULL, 0);
+        if (bufsize > 0) {
+            bufsize += len;
+            if (lnk_added) bufsize += 4;
+            w32buf = ALLOCA_N(char, bufsize);
+            if (cygwin_conv_path(flags, path, w32buf, bufsize) == 0) {
+                b = w32buf;
+            }
+        }
 #else
-	bufsize = MAXPATHLEN;
-	if (cygwin_conv_to_win32_path(path, w32buf) == 0) {
-	    b = w32buf;
-	}
-#endif
-	if (is_symlink && b == w32buf) {
-	    *p = '\\';
-	    strlcat(w32buf, p, bufsize);
-	    if (lnk_added) {
-		strlcat(w32buf, ".lnk", bufsize);
-	    }
-	}
-	else {
-	    lnk_added = 0;
-	}
-	*p = '/';
-#endif
-	rb_str_set_len(result, p - buf + strlen(p));
-	encidx = ENCODING_GET(result);
-	tmp = result;
-	if (encidx != ENCINDEX_UTF_8 && rb_enc_str_coderange(result) != ENC_CODERANGE_7BIT) {
-	    tmp = rb_str_encode_ospath(result);
-	}
-	len = MultiByteToWideChar(CP_UTF8, 0, RSTRING_PTR(tmp), -1, NULL, 0);
-	wstr = ALLOCV_N(WCHAR, v, len);
-	MultiByteToWideChar(CP_UTF8, 0, RSTRING_PTR(tmp), -1, wstr, len);
-	if (tmp != result) rb_str_set_len(tmp, 0);
-	h = FindFirstFileW(wstr, &wfd);
-	ALLOCV_END(v);
-	if (h != INVALID_HANDLE_VALUE) {
-	    size_t wlen;
-	    FindClose(h);
-	    len = lstrlenW(wfd.cFileName);
+        bufsize = MAXPATHLEN;
+        if (cygwin_conv_to_win32_path(path, w32buf) == 0) {
+            b = w32buf;
+        }
+#endif
+        if (is_symlink && b == w32buf) {
+            *p = '\\';
+            strlcat(w32buf, p, bufsize);
+            if (lnk_added) {
+                strlcat(w32buf, ".lnk", bufsize);
+            }
+        }
+        else {
+            lnk_added = 0;
+        }
+        *p = '/';
+#endif
+        rb_str_set_len(result, p - buf + strlen(p));
+        encidx = ENCODING_GET(result);
+        tmp = result;
+        if (encidx != ENCINDEX_UTF_8 && !is_ascii_string(result)) {
+            tmp = rb_str_encode_ospath(result);
+        }
+        len = MultiByteToWideChar(CP_UTF8, 0, RSTRING_PTR(tmp), -1, NULL, 0);
+        wstr = ALLOCV_N(WCHAR, v, len);
+        MultiByteToWideChar(CP_UTF8, 0, RSTRING_PTR(tmp), -1, wstr, len);
+        if (tmp != result) rb_str_set_len(tmp, 0);
+        h = FindFirstFileW(wstr, &wfd);
+        ALLOCV_END(v);
+        if (h != INVALID_HANDLE_VALUE) {
+            size_t wlen;
+            FindClose(h);
+            len = lstrlenW(wfd.cFileName);
 #ifdef __CYGWIN__
-	    if (lnk_added && len > 4 &&
-		wcscasecmp(wfd.cFileName + len - 4, L".lnk") == 0) {
-		wfd.cFileName[len -= 4] = L'\0';
-	    }
+            if (lnk_added && len > 4 &&
+                wcscasecmp(wfd.cFileName + len - 4, L".lnk") == 0) {
+                wfd.cFileName[len -= 4] = L'\0';
+            }
 #else
-	    p = (char *)s;
-#endif
-	    ++p;
-	    wlen = (int)len;
-	    len = WideCharToMultiByte(CP_UTF8, 0, wfd.cFileName, wlen, NULL, 0, NULL, NULL);
-	    if (tmp == result) {
-		BUFCHECK(bdiff + len >= buflen);
-		WideCharToMultiByte(CP_UTF8, 0, wfd.cFileName, wlen, p, len + 1, NULL, NULL);
-	    }
-	    else {
-		rb_str_modify_expand(tmp, len);
-		WideCharToMultiByte(CP_UTF8, 0, wfd.cFileName, wlen, RSTRING_PTR(tmp), len + 1, NULL, NULL);
-		rb_str_cat_conv_enc_opts(result, bdiff, RSTRING_PTR(tmp), len,
-					 rb_utf8_encoding(), 0, Qnil);
-		BUFINIT();
-		rb_str_resize(tmp, 0);
-	    }
-	    p += len;
-	}
+            p = (char *)s;
+#endif
+            ++p;
+            wlen = (int)len;
+            len = WideCharToMultiByte(CP_UTF8, 0, wfd.cFileName, wlen, NULL, 0, NULL, NULL);
+            if (tmp == result) {
+                BUFCHECK(bdiff + len >= buflen);
+                WideCharToMultiByte(CP_UTF8, 0, wfd.cFileName, wlen, p, len + 1, NULL, NULL);
+            }
+            else {
+                rb_str_modify_expand(tmp, len);
+                WideCharToMultiByte(CP_UTF8, 0, wfd.cFileName, wlen, RSTRING_PTR(tmp), len + 1, NULL, NULL);
+                rb_str_cat_conv_enc_opts(result, bdiff, RSTRING_PTR(tmp), len,
+                                         rb_utf8_encoding(), 0, Qnil);
+                BUFINIT();
+                rb_str_resize(tmp, 0);
+            }
+            p += len;
+        }
 #ifdef __CYGWIN__
-	else {
-	    p += strlen(p);
-	}
+        else {
+            p += strlen(p);
+        }
 #endif
     }
 #endif
@@ -4035,7 +4087,7 @@ rb_file_expand_path_internal(VALUE fname, VALUE dname, int abs_mode, int long_na
 }
 #endif /* _WIN32 */
 
-#define EXPAND_PATH_BUFFER() rb_usascii_str_new(0, MAXPATHLEN + 2)
+#define EXPAND_PATH_BUFFER() rb_usascii_str_new(0, 1)
 
 static VALUE
 str_shrink(VALUE str)
@@ -4172,27 +4224,27 @@ enum rb_realpath_mode {
 
 static int
 realpath_rec(long *prefixlenp, VALUE *resolvedp, const char *unresolved, VALUE fallback,
-	     VALUE loopcheck, enum rb_realpath_mode mode, int last)
+             VALUE loopcheck, enum rb_realpath_mode mode, int last)
 {
     const char *pend = unresolved + strlen(unresolved);
     rb_encoding *enc = rb_enc_get(*resolvedp);
     ID resolving;
     CONST_ID(resolving, "resolving");
     while (unresolved < pend) {
-	const char *testname = unresolved;
-	const char *unresolved_firstsep = rb_enc_path_next(unresolved, pend, enc);
-	long testnamelen = unresolved_firstsep - unresolved;
-	const char *unresolved_nextname = unresolved_firstsep;
+        const char *testname = unresolved;
+        const char *unresolved_firstsep = rb_enc_path_next(unresolved, pend, enc);
+        long testnamelen = unresolved_firstsep - unresolved;
+        const char *unresolved_nextname = unresolved_firstsep;
         while (unresolved_nextname < pend && isdirsep(*unresolved_nextname))
-	    unresolved_nextname++;
+            unresolved_nextname++;
         unresolved = unresolved_nextname;
         if (testnamelen == 1 && testname[0] == '.') {
         }
         else if (testnamelen == 2 && testname[0] == '.' && testname[1] == '.') {
             if (*prefixlenp < RSTRING_LEN(*resolvedp)) {
-		const char *resolved_str = RSTRING_PTR(*resolvedp);
-		const char *resolved_names = resolved_str + *prefixlenp;
-		const char *lastsep = strrdirsep(resolved_names, resolved_str + RSTRING_LEN(*resolvedp), enc);
+                const char *resolved_str = RSTRING_PTR(*resolvedp);
+                const char *resolved_names = resolved_str + *prefixlenp;
+                const char *lastsep = strrdirsep(resolved_names, resolved_str + RSTRING_LEN(*resolvedp), enc);
                 long len = lastsep ? lastsep - resolved_names : 0;
                 rb_str_resize(*resolvedp, *prefixlenp + len);
             }
@@ -4203,20 +4255,20 @@ realpath_rec(long *prefixlenp, VALUE *resolvedp, const char *unresolved, VALUE f
             if (*prefixlenp < RSTRING_LEN(testpath))
                 rb_str_cat2(testpath, "/");
 #if defined(DOSISH_UNC) || defined(DOSISH_DRIVE_LETTER)
-	    if (*prefixlenp > 1 && *prefixlenp == RSTRING_LEN(testpath)) {
-		const char *prefix = RSTRING_PTR(testpath);
-		const char *last = rb_enc_left_char_head(prefix, prefix + *prefixlenp - 1, prefix + *prefixlenp, enc);
-		if (!isdirsep(*last)) rb_str_cat2(testpath, "/");
-	    }
+            if (*prefixlenp > 1 && *prefixlenp == RSTRING_LEN(testpath)) {
+                const char *prefix = RSTRING_PTR(testpath);
+                const char *last = rb_enc_left_char_head(prefix, prefix + *prefixlenp - 1, prefix + *prefixlenp, enc);
+                if (!isdirsep(*last)) rb_str_cat2(testpath, "/");
+            }
 #endif
             rb_str_cat(testpath, testname, testnamelen);
             checkval = rb_hash_aref(loopcheck, testpath);
             if (!NIL_P(checkval)) {
                 if (checkval == ID2SYM(resolving)) {
-		    if (mode == RB_REALPATH_CHECK) {
-			errno = ELOOP;
-			return -1;
-		    }
+                    if (mode == RB_REALPATH_CHECK) {
+                        errno = ELOOP;
+                        return -1;
+                    }
                     rb_syserr_fail_path(ELOOP, testpath);
                 }
                 else {
@@ -4228,49 +4280,49 @@ realpath_rec(long *prefixlenp, VALUE *resolvedp, const char *unresolved, VALUE f
                 int ret;
                 ret = lstat_without_gvl(RSTRING_PTR(testpath), &sbuf);
                 if (ret == -1) {
-		    int e = errno;
-		    if (e == ENOENT && !NIL_P(fallback)) {
-			if (stat_without_gvl(RSTRING_PTR(fallback), &sbuf) == 0) {
-			    rb_str_replace(*resolvedp, fallback);
-			    return 0;
-			}
-		    }
-		    if (mode == RB_REALPATH_CHECK) return -1;
-		    if (e == ENOENT) {
-			if (mode == RB_REALPATH_STRICT || !last || *unresolved_firstsep)
-			    rb_syserr_fail_path(e, testpath);
+                    int e = errno;
+                    if (e == ENOENT && !NIL_P(fallback)) {
+                        if (stat_without_gvl(RSTRING_PTR(fallback), &sbuf) == 0) {
+                            rb_str_replace(*resolvedp, fallback);
+                            return 0;
+                        }
+                    }
+                    if (mode == RB_REALPATH_CHECK) return -1;
+                    if (e == ENOENT) {
+                        if (mode == RB_REALPATH_STRICT || !last || *unresolved_firstsep)
+                            rb_syserr_fail_path(e, testpath);
                         *resolvedp = testpath;
                         break;
                     }
                     else {
-			rb_syserr_fail_path(e, testpath);
+                        rb_syserr_fail_path(e, testpath);
                     }
                 }
 #ifdef HAVE_READLINK
                 if (S_ISLNK(sbuf.st_mode)) {
-		    VALUE link;
-		    VALUE link_orig = Qnil;
-		    const char *link_prefix, *link_names;
+                    VALUE link;
+                    VALUE link_orig = Qnil;
+                    const char *link_prefix, *link_names;
                     long link_prefixlen;
                     rb_hash_aset(loopcheck, testpath, ID2SYM(resolving));
-		    link = rb_readlink(testpath, enc);
+                    link = rb_readlink(testpath, enc);
                     link_prefix = RSTRING_PTR(link);
-		    link_names = skipprefixroot(link_prefix, link_prefix + RSTRING_LEN(link), rb_enc_get(link));
-		    link_prefixlen = link_names - link_prefix;
-		    if (link_prefixlen > 0) {
-			rb_encoding *tmpenc, *linkenc = rb_enc_get(link);
-			link_orig = link;
-			link = rb_str_subseq(link, 0, link_prefixlen);
-			tmpenc = fs_enc_check(*resolvedp, link);
-			if (tmpenc != linkenc) link = rb_str_conv_enc(link, linkenc, tmpenc);
-			*resolvedp = link;
-			*prefixlenp = link_prefixlen;
-		    }
-		    if (realpath_rec(prefixlenp, resolvedp, link_names, testpath,
-				     loopcheck, mode, !*unresolved_firstsep))
-			return -1;
-		    RB_GC_GUARD(link_orig);
-		    rb_hash_aset(loopcheck, testpath, rb_str_dup_frozen(*resolvedp));
+                    link_names = skipprefixroot(link_prefix, link_prefix + RSTRING_LEN(link), rb_enc_get(link));
+                    link_prefixlen = link_names - link_prefix;
+                    if (link_prefixlen > 0) {
+                        rb_encoding *tmpenc, *linkenc = rb_enc_get(link);
+                        link_orig = link;
+                        link = rb_str_subseq(link, 0, link_prefixlen);
+                        tmpenc = fs_enc_check(*resolvedp, link);
+                        if (tmpenc != linkenc) link = rb_str_conv_enc(link, linkenc, tmpenc);
+                        *resolvedp = link;
+                        *prefixlenp = link_prefixlen;
+                    }
+                    if (realpath_rec(prefixlenp, resolvedp, link_names, testpath,
+                                     loopcheck, mode, !*unresolved_firstsep))
+                        return -1;
+                    RB_GC_GUARD(link_orig);
+                    rb_hash_aset(loopcheck, testpath, rb_str_dup_frozen(*resolvedp));
                 }
                 else
 #endif
@@ -4316,11 +4368,11 @@ rb_check_realpath_emulate(VALUE basedir, VALUE path, rb_encoding *origenc, enum
     }
 
     if (!NIL_P(basedir)) {
-	RSTRING_GETMEM(basedir, ptr, len);
-	basedir_names = skipprefixroot(ptr, ptr + len, rb_enc_get(basedir));
+        RSTRING_GETMEM(basedir, ptr, len);
+        basedir_names = skipprefixroot(ptr, ptr + len, rb_enc_get(basedir));
         if (ptr != basedir_names) {
-	    resolved = rb_str_subseq(basedir, 0, basedir_names - ptr);
-	    goto root_found;
+            resolved = rb_str_subseq(basedir, 0, basedir_names - ptr);
+            goto root_found;
         }
     }
 
@@ -4339,38 +4391,38 @@ rb_check_realpath_emulate(VALUE basedir, VALUE path, rb_encoding *origenc, enum
     }
 #ifdef FILE_ALT_SEPARATOR
     while (prefixptr < ptr) {
-	if (*prefixptr == FILE_ALT_SEPARATOR) {
-	    *prefixptr = '/';
-	}
-	Inc(prefixptr, pend, enc);
+        if (*prefixptr == FILE_ALT_SEPARATOR) {
+            *prefixptr = '/';
+        }
+        Inc(prefixptr, pend, enc);
     }
 #endif
 
     switch (rb_enc_to_index(enc)) {
-      case ENCINDEX_ASCII:
+      case ENCINDEX_ASCII_8BIT:
       case ENCINDEX_US_ASCII:
-	rb_enc_associate_index(resolved, rb_filesystem_encindex());
+        rb_enc_associate_index(resolved, rb_filesystem_encindex());
     }
 
     loopcheck = rb_hash_new();
     if (curdir_names) {
-	if (realpath_rec(&prefixlen, &resolved, curdir_names, Qnil, loopcheck, mode, 0))
-	    return Qnil;
+        if (realpath_rec(&prefixlen, &resolved, curdir_names, Qnil, loopcheck, mode, 0))
+            return Qnil;
     }
     if (basedir_names) {
-	if (realpath_rec(&prefixlen, &resolved, basedir_names, Qnil, loopcheck, mode, 0))
-	    return Qnil;
+        if (realpath_rec(&prefixlen, &resolved, basedir_names, Qnil, loopcheck, mode, 0))
+            return Qnil;
     }
     if (realpath_rec(&prefixlen, &resolved, path_names, Qnil, loopcheck, mode, 1))
-	return Qnil;
+        return Qnil;
 
     if (origenc && origenc != rb_enc_get(resolved)) {
-	if (rb_enc_str_asciionly_p(resolved)) {
-	    rb_enc_associate(resolved, origenc);
-	}
-	else {
-	    resolved = rb_str_conv_enc(resolved, NULL, origenc);
-	}
+        if (rb_enc_str_asciionly_p(resolved)) {
+            rb_enc_associate(resolved, origenc);
+        }
+        else {
+            resolved = rb_str_conv_enc(resolved, NULL, origenc);
+        }
     }
 
     RB_GC_GUARD(unresolved_path);
@@ -4451,9 +4503,9 @@ rb_check_realpath_internal(VALUE basedir, VALUE path, rb_encoding *origenc, enum
         rb_enc_associate(resolved, origenc);
     }
 
-    if (rb_enc_str_coderange(resolved) == ENC_CODERANGE_BROKEN) {
+    if (is_broken_string(resolved)) {
         rb_enc_associate(resolved, rb_filesystem_encoding());
-        if (rb_enc_str_coderange(resolved) == ENC_CODERANGE_BROKEN) {
+        if (is_broken_string(resolved)) {
             rb_enc_associate(resolved, rb_ascii8bit_encoding());
         }
     }
@@ -4480,7 +4532,7 @@ VALUE
 rb_realpath_internal(VALUE basedir, VALUE path, int strict)
 {
     const enum rb_realpath_mode mode =
-	strict ? RB_REALPATH_STRICT : RB_REALPATH_DIR;
+        strict ? RB_REALPATH_STRICT : RB_REALPATH_DIR;
     return rb_check_realpath_internal(basedir, path, rb_enc_get(path), mode);
 }
 
@@ -4544,15 +4596,15 @@ rmext(const char *p, long l0, long l1, const char *e, long l2, rb_encoding *enc)
 
     c = rb_enc_codepoint_len(e, e + l2, &len1, enc);
     if (rb_enc_ascget(e + len1, e + l2, &len2, enc) == '*' && len1 + len2 == l2) {
-	if (c == '.') return l0;
-	s = p;
-	e = p + l1;
-	last = e;
-	while (s < e) {
-	    if (rb_enc_codepoint_len(s, e, &len1, enc) == c) last = s;
-	    s += len1;
-	}
-	return last - p;
+        if (c == '.') return l0;
+        s = p;
+        e = p + l1;
+        last = e;
+        while (s < e) {
+            if (rb_enc_codepoint_len(s, e, &len1, enc) == c) last = s;
+            s += len1;
+        }
+        return last - p;
     }
     if (l1 < l2) return l1;
 
@@ -4564,7 +4616,7 @@ rmext(const char *p, long l0, long l1, const char *e, long l2, rb_encoding *enc)
 #define fncomp strncmp
 #endif
     if (fncomp(s, e, l2) == 0) {
-	return l1-l2;
+        return l1-l2;
     }
     return 0;
 }
@@ -4584,51 +4636,51 @@ ruby_enc_find_basename(const char *name, long *baselen, long *alllen, rb_encodin
     root = name;
 #endif
     while (isdirsep(*name))
-	name++;
+        name++;
     if (!*name) {
-	p = name - 1;
-	f = 1;
+        p = name - 1;
+        f = 1;
 #if defined DOSISH_DRIVE_LETTER || defined DOSISH_UNC
-	if (name != root) {
-	    /* has slashes */
-	}
+        if (name != root) {
+            /* has slashes */
+        }
 #ifdef DOSISH_DRIVE_LETTER
-	else if (*p == ':') {
-	    p++;
-	    f = 0;
-	}
+        else if (*p == ':') {
+            p++;
+            f = 0;
+        }
 #endif
 #ifdef DOSISH_UNC
-	else {
-	    p = "/";
-	}
+        else {
+            p = "/";
+        }
 #endif
 #endif
     }
     else {
-	if (!(p = strrdirsep(name, end, enc))) {
-	    p = name;
-	}
-	else {
-	    while (isdirsep(*p)) p++; /* skip last / */
-	}
+        if (!(p = strrdirsep(name, end, enc))) {
+            p = name;
+        }
+        else {
+            while (isdirsep(*p)) p++; /* skip last / */
+        }
 #if USE_NTFS
-	n = ntfs_tail(p, end, enc) - p;
+        n = ntfs_tail(p, end, enc) - p;
 #else
-	n = chompdirsep(p, end, enc) - p;
+        n = chompdirsep(p, end, enc) - p;
 #endif
-	for (q = p; q - p < n && *q == '.'; q++);
-	for (e = 0; q - p < n; Inc(q, end, enc)) {
-	    if (*q == '.') e = q;
-	}
-	if (e) f = e - p;
-	else f = n;
+        for (q = p; q - p < n && *q == '.'; q++);
+        for (e = 0; q - p < n; Inc(q, end, enc)) {
+            if (*q == '.') e = q;
+        }
+        if (e) f = e - p;
+        else f = n;
     }
 
     if (baselen)
-	*baselen = f;
+        *baselen = f;
     if (alllen)
-	*alllen = n;
+        *alllen = n;
     return p;
 }
 
@@ -4659,33 +4711,33 @@ rb_file_s_basename(int argc, VALUE *argv, VALUE _)
 
     fext = Qnil;
     if (rb_check_arity(argc, 1, 2) == 2) {
-	fext = argv[1];
-	StringValue(fext);
-	enc = check_path_encoding(fext);
+        fext = argv[1];
+        StringValue(fext);
+        enc = check_path_encoding(fext);
     }
     fname = argv[0];
     FilePathStringValue(fname);
     if (NIL_P(fext) || !(enc = rb_enc_compatible(fname, fext))) {
-	enc = rb_enc_get(fname);
-	fext = Qnil;
+        enc = rb_enc_get(fname);
+        fext = Qnil;
     }
     if ((n = RSTRING_LEN(fname)) == 0 || !*(name = RSTRING_PTR(fname)))
-	return rb_str_new_shared(fname);
+        return rb_str_new_shared(fname);
 
     p = ruby_enc_find_basename(name, &f, &n, enc);
     if (n >= 0) {
-	if (NIL_P(fext)) {
-	    f = n;
-	}
-	else {
-	    const char *fp;
-	    fp = StringValueCStr(fext);
-	    if (!(f = rmext(p, f, n, fp, RSTRING_LEN(fext), enc))) {
-		f = n;
-	    }
-	    RB_GC_GUARD(fext);
-	}
-	if (f == RSTRING_LEN(fname)) return rb_str_new_shared(fname);
+        if (NIL_P(fext)) {
+            f = n;
+        }
+        else {
+            const char *fp;
+            fp = StringValueCStr(fext);
+            if (!(f = rmext(p, f, n, fp, RSTRING_LEN(fext), enc))) {
+                f = n;
+            }
+            RB_GC_GUARD(fext);
+        }
+        if (f == RSTRING_LEN(fname)) return rb_str_new_shared(fname);
     }
 
     basename = rb_str_new(p, f);
@@ -4719,7 +4771,7 @@ rb_file_s_dirname(int argc, VALUE *argv, VALUE klass)
 {
     int n = 1;
     if ((argc = rb_check_arity(argc, 1, 2)) > 1) {
-	n = NUM2INT(argv[1]);
+        n = NUM2INT(argv[1]);
     }
     return rb_file_dirname_n(argv[0], n);
 }
@@ -4747,58 +4799,58 @@ rb_file_dirname_n(VALUE fname, int n)
     root = skiproot(name, end, enc);
 #ifdef DOSISH_UNC
     if (root > name + 1 && isdirsep(*name))
-	root = skipprefix(name = root - 2, end, enc);
+        root = skipprefix(name = root - 2, end, enc);
 #else
     if (root > name + 1)
-	name = root - 1;
+        name = root - 1;
 #endif
     if (n > (end - root + 1) / 2) {
-	p = root;
+        p = root;
     }
     else {
-	int i;
-	switch (n) {
-	  case 0:
-	    p = end;
-	    break;
-	  case 1:
-	    if (!(p = strrdirsep(root, end, enc))) p = root;
-	    break;
-	  default:
-	    seps = ALLOCV_N(const char *, sepsv, n);
-	    for (i = 0; i < n; ++i) seps[i] = root;
-	    i = 0;
-	    for (p = root; p < end; ) {
-		if (isdirsep(*p)) {
-		    const char *tmp = p++;
-		    while (p < end && isdirsep(*p)) p++;
-		    if (p >= end) break;
-		    seps[i++] = tmp;
-		    if (i == n) i = 0;
-		}
-		else {
-		    Inc(p, end, enc);
-		}
-	    }
-	    p = seps[i];
-	    ALLOCV_END(sepsv);
-	    break;
-	}
+        int i;
+        switch (n) {
+          case 0:
+            p = end;
+            break;
+          case 1:
+            if (!(p = strrdirsep(root, end, enc))) p = root;
+            break;
+          default:
+            seps = ALLOCV_N(const char *, sepsv, n);
+            for (i = 0; i < n; ++i) seps[i] = root;
+            i = 0;
+            for (p = root; p < end; ) {
+                if (isdirsep(*p)) {
+                    const char *tmp = p++;
+                    while (p < end && isdirsep(*p)) p++;
+                    if (p >= end) break;
+                    seps[i++] = tmp;
+                    if (i == n) i = 0;
+                }
+                else {
+                    Inc(p, end, enc);
+                }
+            }
+            p = seps[i];
+            ALLOCV_END(sepsv);
+            break;
+        }
     }
     if (p == name)
-	return rb_usascii_str_new2(".");
+        return rb_usascii_str_new2(".");
 #ifdef DOSISH_DRIVE_LETTER
     if (has_drive_letter(name) && isdirsep(*(name + 2))) {
-	const char *top = skiproot(name + 2, end, enc);
-	dirname = rb_str_new(name, 3);
-	rb_str_cat(dirname, top, p - top);
+        const char *top = skiproot(name + 2, end, enc);
+        dirname = rb_str_new(name, 3);
+        rb_str_cat(dirname, top, p - top);
     }
     else
 #endif
     dirname = rb_str_new(name, p - name);
 #ifdef DOSISH_DRIVE_LETTER
     if (has_drive_letter(name) && root == name + 2 && p - name == 2)
-	rb_str_cat(dirname, ".", 1);
+        rb_str_cat(dirname, ".", 1);
 #endif
     rb_enc_copy(dirname, fname);
     return dirname;
@@ -4813,7 +4865,7 @@ rb_file_dirname_n(VALUE fname, int n)
  *   dotfile       top       0
  *   end with dot  dot       1
  *   .ext          dot       len of .ext
- *   .ext:stream   dot       len of .ext without :stream (NT only)
+ *   .ext:stream   dot       len of .ext without :stream (NTFS only)
  *
  */
 const char *
@@ -4823,48 +4875,48 @@ ruby_enc_find_extname(const char *name, long *len, rb_encoding *enc)
 
     p = strrdirsep(name, end, enc);	/* get the last path component */
     if (!p)
-	p = name;
+        p = name;
     else
-	do name = ++p; while (isdirsep(*p));
+        do name = ++p; while (isdirsep(*p));
 
     e = 0;
     while (*p && *p == '.') p++;
     while (*p) {
-	if (*p == '.' || istrailinggarbage(*p)) {
+        if (*p == '.' || istrailinggarbage(*p)) {
 #if USE_NTFS
-	    const char *last = p++, *dot = last;
-	    while (istrailinggarbage(*p)) {
-		if (*p == '.') dot = p;
-		p++;
-	    }
-	    if (!*p || isADS(*p)) {
-		p = last;
-		break;
-	    }
-	    if (*last == '.' || dot > last) e = dot;
-	    continue;
+            const char *last = p++, *dot = last;
+            while (istrailinggarbage(*p)) {
+                if (*p == '.') dot = p;
+                p++;
+            }
+            if (!*p || isADS(*p)) {
+                p = last;
+                break;
+            }
+            if (*last == '.' || dot > last) e = dot;
+            continue;
 #else
-	    e = p;	  /* get the last dot of the last component */
+            e = p;	  /* get the last dot of the last component */
 #endif
-	}
+        }
 #if USE_NTFS
-	else if (isADS(*p)) {
-	    break;
-	}
+        else if (isADS(*p)) {
+            break;
+        }
 #endif
-	else if (isdirsep(*p))
-	    break;
-	Inc(p, end, enc);
+        else if (isdirsep(*p))
+            break;
+        Inc(p, end, enc);
     }
 
     if (len) {
-	/* no dot, or the only dot is first or end? */
-	if (!e || e == name)
-	    *len = 0;
-	else if (e+1 == p)
-	    *len = 1;
-	else
-	    *len = p - e;
+        /* no dot, or the only dot is first or end? */
+        if (!e || e == name)
+            *len = 0;
+        else if (e+1 == p)
+            *len = 1;
+        else
+            *len = p - e;
     }
     return e;
 }
@@ -4907,7 +4959,7 @@ rb_file_s_extname(VALUE klass, VALUE fname)
     len = RSTRING_LEN(fname);
     e = ruby_enc_find_extname(name, &len, rb_enc_get(fname));
     if (len < 1)
-	return rb_str_new(0, 0);
+        return rb_str_new(0, 0);
     extname = rb_str_subseq(fname, e - name, len); /* keep the dot, too! */
     return extname;
 }
@@ -4967,53 +5019,53 @@ rb_file_join(VALUE ary)
 
     len = 1;
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	tmp = RARRAY_AREF(ary, i);
-	if (RB_TYPE_P(tmp, T_STRING)) {
-	    check_path_encoding(tmp);
-	    len += RSTRING_LEN(tmp);
-	}
-	else {
-	    len += 10;
-	}
+        tmp = RARRAY_AREF(ary, i);
+        if (RB_TYPE_P(tmp, T_STRING)) {
+            check_path_encoding(tmp);
+            len += RSTRING_LEN(tmp);
+        }
+        else {
+            len += 10;
+        }
     }
     len += RARRAY_LEN(ary) - 1;
     result = rb_str_buf_new(len);
     RBASIC_CLEAR_CLASS(result);
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	tmp = RARRAY_AREF(ary, i);
-	switch (OBJ_BUILTIN_TYPE(tmp)) {
-	  case T_STRING:
-	    if (!checked) check_path_encoding(tmp);
-	    StringValueCStr(tmp);
-	    break;
-	  case T_ARRAY:
-	    if (ary == tmp) {
-		rb_raise(rb_eArgError, "recursive array");
-	    }
-	    else {
-		tmp = rb_exec_recursive(file_inspect_join, ary, tmp);
-	    }
-	    break;
-	  default:
-	    FilePathStringValue(tmp);
-	    checked = FALSE;
-	}
-	RSTRING_GETMEM(result, name, len);
-	if (i == 0) {
-	    rb_enc_copy(result, tmp);
-	}
-	else {
-	    tail = chompdirsep(name, name + len, rb_enc_get(result));
-	    if (RSTRING_PTR(tmp) && isdirsep(RSTRING_PTR(tmp)[0])) {
-		rb_str_set_len(result, tail - name);
-	    }
-	    else if (!*tail) {
-		rb_str_cat(result, "/", 1);
-	    }
-	}
-	enc = fs_enc_check(result, tmp);
-	rb_str_buf_append(result, tmp);
-	rb_enc_associate(result, enc);
+        tmp = RARRAY_AREF(ary, i);
+        switch (OBJ_BUILTIN_TYPE(tmp)) {
+          case T_STRING:
+            if (!checked) check_path_encoding(tmp);
+            StringValueCStr(tmp);
+            break;
+          case T_ARRAY:
+            if (ary == tmp) {
+                rb_raise(rb_eArgError, "recursive array");
+            }
+            else {
+                tmp = rb_exec_recursive(file_inspect_join, ary, tmp);
+            }
+            break;
+          default:
+            FilePathStringValue(tmp);
+            checked = FALSE;
+        }
+        RSTRING_GETMEM(result, name, len);
+        if (i == 0) {
+            rb_enc_copy(result, tmp);
+        }
+        else {
+            tail = chompdirsep(name, name + len, rb_enc_get(result));
+            if (RSTRING_PTR(tmp) && isdirsep(RSTRING_PTR(tmp)[0])) {
+                rb_str_set_len(result, tail - name);
+            }
+            else if (!*tail) {
+                rb_str_cat(result, "/", 1);
+            }
+        }
+        enc = fs_enc_check(result, tmp);
+        rb_str_buf_append(result, tmp);
+        rb_enc_associate(result, enc);
     }
     RBASIC_SET_CLASS_RAW(result, rb_cString);
 
@@ -5037,41 +5089,17 @@ rb_file_s_join(VALUE klass, VALUE args)
     return rb_file_join(args);
 }
 
-#if defined(HAVE_TRUNCATE) || defined(HAVE_CHSIZE)
+#if defined(HAVE_TRUNCATE)
 struct truncate_arg {
     const char *path;
-#if defined(HAVE_TRUNCATE)
-#define NUM2POS(n) NUM2OFFT(n)
-    off_t pos;
-#else
-#define NUM2POS(n) NUM2LONG(n)
-    long pos;
-#endif
+    rb_off_t pos;
 };
 
 static void *
 nogvl_truncate(void *ptr)
 {
     struct truncate_arg *ta = ptr;
-#ifdef HAVE_TRUNCATE
     return (void *)(VALUE)truncate(ta->path, ta->pos);
-#else /* defined(HAVE_CHSIZE) */
-    {
-	int tmpfd = rb_cloexec_open(ta->path, 0, 0);
-
-	if (tmpfd < 0)
-	    return (void *)-1;
-	rb_update_max_fd(tmpfd);
-	if (chsize(tmpfd, ta->pos) < 0) {
-	    int e = errno;
-	    close(tmpfd);
-	    errno = e;
-	    return (void *)-1;
-	}
-	close(tmpfd);
-	return 0;
-    }
-#endif
 }
 
 /*
@@ -5095,32 +5123,25 @@ rb_file_s_truncate(VALUE klass, VALUE path, VALUE len)
     struct truncate_arg ta;
     int r;
 
-    ta.pos = NUM2POS(len);
+    ta.pos = NUM2OFFT(len);
     FilePathValue(path);
     path = rb_str_encode_ospath(path);
     ta.path = StringValueCStr(path);
 
     r = (int)(VALUE)rb_thread_call_without_gvl(nogvl_truncate, &ta,
-						RUBY_UBF_IO, NULL);
+                                                RUBY_UBF_IO, NULL);
     if (r < 0)
-	rb_sys_fail_path(path);
+        rb_sys_fail_path(path);
     return INT2FIX(0);
-#undef NUM2POS
 }
 #else
 #define rb_file_s_truncate rb_f_notimplement
 #endif
 
-#if defined(HAVE_FTRUNCATE) || defined(HAVE_CHSIZE)
+#if defined(HAVE_FTRUNCATE)
 struct ftruncate_arg {
     int fd;
-#if defined(HAVE_FTRUNCATE)
-#define NUM2POS(n) NUM2OFFT(n)
-    off_t pos;
-#else
-#define NUM2POS(n) NUM2LONG(n)
-    long pos;
-#endif
+    rb_off_t pos;
 };
 
 static VALUE
@@ -5128,11 +5149,7 @@ nogvl_ftruncate(void *ptr)
 {
     struct ftruncate_arg *fa = ptr;
 
-#ifdef HAVE_FTRUNCATE
     return (VALUE)ftruncate(fa->fd, fa->pos);
-#else /* defined(HAVE_CHSIZE) */
-    return (VALUE)chsize(fa->fd, fa->pos);
-#endif
 }
 
 /*
@@ -5155,18 +5172,17 @@ rb_file_truncate(VALUE obj, VALUE len)
     rb_io_t *fptr;
     struct ftruncate_arg fa;
 
-    fa.pos = NUM2POS(len);
+    fa.pos = NUM2OFFT(len);
     GetOpenFile(obj, fptr);
     if (!(fptr->mode & FMODE_WRITABLE)) {
-	rb_raise(rb_eIOError, "not opened for writing");
+        rb_raise(rb_eIOError, "not opened for writing");
     }
     rb_io_flush_raw(obj, 0);
     fa.fd = fptr->fd;
     if ((int)rb_thread_io_blocking_region(nogvl_ftruncate, &fa, fa.fd) < 0) {
-	rb_sys_fail_path(fptr->pathv);
+        rb_sys_fail_path(fptr->pathv);
     }
     return INT2FIX(0);
-#undef NUM2POS
 }
 #else
 #define rb_file_truncate rb_f_notimplement
@@ -5199,8 +5215,8 @@ rb_thread_flock(void *data)
 
 #ifdef __CYGWIN__
     if (GetLastError() == ERROR_NOT_LOCKED) {
-	ret = 0;
-	errno = old_errno;
+        ret = 0;
+        errno = old_errno;
     }
 #endif
     return (VALUE)ret;
@@ -5262,33 +5278,33 @@ rb_file_flock(VALUE obj, VALUE operation)
     op[0] = fptr->fd;
 
     if (fptr->mode & FMODE_WRITABLE) {
-	rb_io_flush_raw(obj, 0);
+        rb_io_flush_raw(obj, 0);
     }
     while ((int)rb_thread_io_blocking_region(rb_thread_flock, op, fptr->fd) < 0) {
-	int e = errno;
-	switch (e) {
-	  case EAGAIN:
-	  case EACCES:
+        int e = errno;
+        switch (e) {
+          case EAGAIN:
+          case EACCES:
 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
-	  case EWOULDBLOCK:
+          case EWOULDBLOCK:
 #endif
-	    if (op1 & LOCK_NB) return Qfalse;
+            if (op1 & LOCK_NB) return Qfalse;
 
-	    time.tv_sec = 0;
-	    time.tv_usec = 100 * 1000;	/* 0.1 sec */
-	    rb_thread_wait_for(time);
-	    rb_io_check_closed(fptr);
-	    continue;
+            time.tv_sec = 0;
+            time.tv_usec = 100 * 1000;	/* 0.1 sec */
+            rb_thread_wait_for(time);
+            rb_io_check_closed(fptr);
+            continue;
 
-	  case EINTR:
+          case EINTR:
 #if defined(ERESTART)
-	  case ERESTART:
+          case ERESTART:
 #endif
-	    break;
+            break;
 
-	  default:
-	    rb_syserr_fail_path(e, fptr->pathv);
-	}
+          default:
+            rb_syserr_fail_path(e, fptr->pathv);
+        }
     }
     return INT2FIX(0);
 }
@@ -5301,9 +5317,9 @@ test_check(int n, int argc, VALUE *argv)
     n+=1;
     rb_check_arity(argc, n, n);
     for (i=1; i<n; i++) {
-	if (!RB_TYPE_P(argv[i], T_FILE)) {
-	    FilePathValue(argv[i]);
-	}
+        if (!RB_TYPE_P(argv[i], T_FILE)) {
+            FilePathValue(argv[i]);
+        }
     }
 }
 
@@ -5326,8 +5342,7 @@ test_check(int n, int argc, VALUE *argv)
  *    "d"  | boolean | True if file1 exists and is a directory
  *    "e"  | boolean | True if file1 exists
  *    "f"  | boolean | True if file1 exists and is a regular file
- *    "g"  | boolean | True if file1 has the \CF{setgid} bit
- *         |         | set (false under NT)
+ *    "g"  | boolean | True if file1 has the setgid bit set
  *    "G"  | boolean | True if file1 exists and has a group
  *         |         | ownership equal to the caller's group
  *    "k"  | boolean | True if file1 exists and has the sticky bit set
@@ -5378,128 +5393,128 @@ rb_f_test(int argc, VALUE *argv, VALUE _)
         goto unknown;
     }
     if (strchr("bcdefgGkloOprRsSuwWxXz", cmd)) {
-	CHECK(1);
-	switch (cmd) {
-	  case 'b':
-	    return rb_file_blockdev_p(0, argv[1]);
+        CHECK(1);
+        switch (cmd) {
+          case 'b':
+            return rb_file_blockdev_p(0, argv[1]);
 
-	  case 'c':
-	    return rb_file_chardev_p(0, argv[1]);
+          case 'c':
+            return rb_file_chardev_p(0, argv[1]);
 
-	  case 'd':
-	    return rb_file_directory_p(0, argv[1]);
+          case 'd':
+            return rb_file_directory_p(0, argv[1]);
 
-	  case 'e':
-	    return rb_file_exist_p(0, argv[1]);
+          case 'e':
+            return rb_file_exist_p(0, argv[1]);
 
-	  case 'f':
-	    return rb_file_file_p(0, argv[1]);
+          case 'f':
+            return rb_file_file_p(0, argv[1]);
 
-	  case 'g':
-	    return rb_file_sgid_p(0, argv[1]);
+          case 'g':
+            return rb_file_sgid_p(0, argv[1]);
 
-	  case 'G':
-	    return rb_file_grpowned_p(0, argv[1]);
+          case 'G':
+            return rb_file_grpowned_p(0, argv[1]);
 
-	  case 'k':
-	    return rb_file_sticky_p(0, argv[1]);
+          case 'k':
+            return rb_file_sticky_p(0, argv[1]);
 
-	  case 'l':
-	    return rb_file_symlink_p(0, argv[1]);
+          case 'l':
+            return rb_file_symlink_p(0, argv[1]);
 
-	  case 'o':
-	    return rb_file_owned_p(0, argv[1]);
+          case 'o':
+            return rb_file_owned_p(0, argv[1]);
 
-	  case 'O':
-	    return rb_file_rowned_p(0, argv[1]);
+          case 'O':
+            return rb_file_rowned_p(0, argv[1]);
 
-	  case 'p':
-	    return rb_file_pipe_p(0, argv[1]);
+          case 'p':
+            return rb_file_pipe_p(0, argv[1]);
 
-	  case 'r':
-	    return rb_file_readable_p(0, argv[1]);
+          case 'r':
+            return rb_file_readable_p(0, argv[1]);
 
-	  case 'R':
-	    return rb_file_readable_real_p(0, argv[1]);
+          case 'R':
+            return rb_file_readable_real_p(0, argv[1]);
 
-	  case 's':
-	    return rb_file_size_p(0, argv[1]);
+          case 's':
+            return rb_file_size_p(0, argv[1]);
 
-	  case 'S':
-	    return rb_file_socket_p(0, argv[1]);
+          case 'S':
+            return rb_file_socket_p(0, argv[1]);
 
-	  case 'u':
-	    return rb_file_suid_p(0, argv[1]);
+          case 'u':
+            return rb_file_suid_p(0, argv[1]);
 
-	  case 'w':
-	    return rb_file_writable_p(0, argv[1]);
+          case 'w':
+            return rb_file_writable_p(0, argv[1]);
 
-	  case 'W':
-	    return rb_file_writable_real_p(0, argv[1]);
+          case 'W':
+            return rb_file_writable_real_p(0, argv[1]);
 
-	  case 'x':
-	    return rb_file_executable_p(0, argv[1]);
+          case 'x':
+            return rb_file_executable_p(0, argv[1]);
 
-	  case 'X':
-	    return rb_file_executable_real_p(0, argv[1]);
+          case 'X':
+            return rb_file_executable_real_p(0, argv[1]);
 
-	  case 'z':
-	    return rb_file_zero_p(0, argv[1]);
-	}
+          case 'z':
+            return rb_file_zero_p(0, argv[1]);
+        }
     }
 
     if (strchr("MAC", cmd)) {
-	struct stat st;
-	VALUE fname = argv[1];
-
-	CHECK(1);
-	if (rb_stat(fname, &st) == -1) {
-	    int e = errno;
-	    FilePathValue(fname);
-	    rb_syserr_fail_path(e, fname);
-	}
-
-	switch (cmd) {
-	  case 'A':
-	    return stat_atime(&st);
-	  case 'M':
-	    return stat_mtime(&st);
-	  case 'C':
-	    return stat_ctime(&st);
-	}
+        struct stat st;
+        VALUE fname = argv[1];
+
+        CHECK(1);
+        if (rb_stat(fname, &st) == -1) {
+            int e = errno;
+            FilePathValue(fname);
+            rb_syserr_fail_path(e, fname);
+        }
+
+        switch (cmd) {
+          case 'A':
+            return stat_atime(&st);
+          case 'M':
+            return stat_mtime(&st);
+          case 'C':
+            return stat_ctime(&st);
+        }
     }
 
     if (cmd == '-') {
-	CHECK(2);
-	return rb_file_identical_p(0, argv[1], argv[2]);
+        CHECK(2);
+        return rb_file_identical_p(0, argv[1], argv[2]);
     }
 
     if (strchr("=<>", cmd)) {
-	struct stat st1, st2;
+        struct stat st1, st2;
         struct timespec t1, t2;
 
-	CHECK(2);
-	if (rb_stat(argv[1], &st1) < 0) return Qfalse;
-	if (rb_stat(argv[2], &st2) < 0) return Qfalse;
+        CHECK(2);
+        if (rb_stat(argv[1], &st1) < 0) return Qfalse;
+        if (rb_stat(argv[2], &st2) < 0) return Qfalse;
 
         t1 = stat_mtimespec(&st1);
         t2 = stat_mtimespec(&st2);
 
-	switch (cmd) {
-	  case '=':
-	    if (t1.tv_sec == t2.tv_sec && t1.tv_nsec == t2.tv_nsec) return Qtrue;
-	    return Qfalse;
+        switch (cmd) {
+          case '=':
+            if (t1.tv_sec == t2.tv_sec && t1.tv_nsec == t2.tv_nsec) return Qtrue;
+            return Qfalse;
 
-	  case '>':
-	    if (t1.tv_sec > t2.tv_sec) return Qtrue;
-	    if (t1.tv_sec == t2.tv_sec && t1.tv_nsec > t2.tv_nsec) return Qtrue;
-	    return Qfalse;
+          case '>':
+            if (t1.tv_sec > t2.tv_sec) return Qtrue;
+            if (t1.tv_sec == t2.tv_sec && t1.tv_nsec > t2.tv_nsec) return Qtrue;
+            return Qfalse;
 
-	  case '<':
-	    if (t1.tv_sec < t2.tv_sec) return Qtrue;
-	    if (t1.tv_sec == t2.tv_sec && t1.tv_nsec < t2.tv_nsec) return Qtrue;
-	    return Qfalse;
-	}
+          case '<':
+            if (t1.tv_sec < t2.tv_sec) return Qtrue;
+            if (t1.tv_sec == t2.tv_sec && t1.tv_nsec < t2.tv_nsec) return Qtrue;
+            return Qfalse;
+        }
     }
   unknown:
     /* unknown command */
@@ -5548,11 +5563,12 @@ rb_stat_init(VALUE obj, VALUE fname)
     FilePathValue(fname);
     fname = rb_str_encode_ospath(fname);
     if (STAT(StringValueCStr(fname), &st) == -1) {
-	rb_sys_fail_path(fname);
+        rb_sys_fail_path(fname);
     }
+
     if (DATA_PTR(obj)) {
-	xfree(DATA_PTR(obj));
-	DATA_PTR(obj) = NULL;
+        xfree(DATA_PTR(obj));
+        DATA_PTR(obj) = NULL;
     }
     nst = ALLOC(struct stat);
     *nst = st;
@@ -5569,13 +5585,13 @@ rb_stat_init_copy(VALUE copy, VALUE orig)
 
     if (!OBJ_INIT_COPY(copy, orig)) return copy;
     if (DATA_PTR(copy)) {
-	xfree(DATA_PTR(copy));
-	DATA_PTR(copy) = 0;
+        xfree(DATA_PTR(copy));
+        DATA_PTR(copy) = 0;
     }
     if (DATA_PTR(orig)) {
-	nst = ALLOC(struct stat);
-	*nst = *(struct stat*)DATA_PTR(orig);
-	DATA_PTR(copy) = nst;
+        nst = ALLOC(struct stat);
+        *nst = *(struct stat*)DATA_PTR(orig);
+        DATA_PTR(copy) = nst;
     }
 
     return copy;
@@ -5758,7 +5774,7 @@ rb_stat_rowned(VALUE obj)
  *     stat.grpowned?   -> true or false
  *
  *  Returns true if the effective group id of the process is the same as
- *  the group id of <i>stat</i>. On Windows NT, returns <code>false</code>.
+ *  the group id of <i>stat</i>. On Windows, returns <code>false</code>.
  *
  *     File.stat("testfile").grpowned?      #=> true
  *     File.stat("/etc/passwd").grpowned?   #=> false
@@ -5795,11 +5811,11 @@ rb_stat_r(VALUE obj)
 #endif
 #ifdef S_IRUSR
     if (rb_stat_owned(obj))
-	return RBOOL(st->st_mode & S_IRUSR);
+        return RBOOL(st->st_mode & S_IRUSR);
 #endif
 #ifdef S_IRGRP
     if (rb_stat_grpowned(obj))
-	return RBOOL(st->st_mode & S_IRGRP);
+        return RBOOL(st->st_mode & S_IRGRP);
 #endif
 #ifdef S_IROTH
     if (!(st->st_mode & S_IROTH)) return Qfalse;
@@ -5828,11 +5844,11 @@ rb_stat_R(VALUE obj)
 #endif
 #ifdef S_IRUSR
     if (rb_stat_rowned(obj))
-	return RBOOL(st->st_mode & S_IRUSR);
+        return RBOOL(st->st_mode & S_IRUSR);
 #endif
 #ifdef S_IRGRP
     if (rb_group_member(get_stat(obj)->st_gid))
-	return RBOOL(st->st_mode & S_IRGRP);
+        return RBOOL(st->st_mode & S_IRGRP);
 #endif
 #ifdef S_IROTH
     if (!(st->st_mode & S_IROTH)) return Qfalse;
@@ -5859,10 +5875,10 @@ rb_stat_wr(VALUE obj)
 #ifdef S_IROTH
     struct stat *st = get_stat(obj);
     if ((st->st_mode & (S_IROTH)) == S_IROTH) {
-	return UINT2NUM(st->st_mode & (S_IRUGO|S_IWUGO|S_IXUGO));
+        return UINT2NUM(st->st_mode & (S_IRUGO|S_IWUGO|S_IXUGO));
     }
     else {
-	return Qnil;
+        return Qnil;
     }
 #endif
 }
@@ -5888,11 +5904,11 @@ rb_stat_w(VALUE obj)
 #endif
 #ifdef S_IWUSR
     if (rb_stat_owned(obj))
-	return RBOOL(st->st_mode & S_IWUSR);
+        return RBOOL(st->st_mode & S_IWUSR);
 #endif
 #ifdef S_IWGRP
     if (rb_stat_grpowned(obj))
-	return RBOOL(st->st_mode & S_IWGRP);
+        return RBOOL(st->st_mode & S_IWGRP);
 #endif
 #ifdef S_IWOTH
     if (!(st->st_mode & S_IWOTH)) return Qfalse;
@@ -5921,11 +5937,11 @@ rb_stat_W(VALUE obj)
 #endif
 #ifdef S_IWUSR
     if (rb_stat_rowned(obj))
-	return RBOOL(st->st_mode & S_IWUSR);
+        return RBOOL(st->st_mode & S_IWUSR);
 #endif
 #ifdef S_IWGRP
     if (rb_group_member(get_stat(obj)->st_gid))
-	return RBOOL(st->st_mode & S_IWGRP);
+        return RBOOL(st->st_mode & S_IWGRP);
 #endif
 #ifdef S_IWOTH
     if (!(st->st_mode & S_IWOTH)) return Qfalse;
@@ -5952,10 +5968,10 @@ rb_stat_ww(VALUE obj)
 #ifdef S_IROTH
     struct stat *st = get_stat(obj);
     if ((st->st_mode & (S_IWOTH)) == S_IWOTH) {
-	return UINT2NUM(st->st_mode & (S_IRUGO|S_IWUGO|S_IXUGO));
+        return UINT2NUM(st->st_mode & (S_IRUGO|S_IWUGO|S_IXUGO));
     }
     else {
-	return Qnil;
+        return Qnil;
     }
 #endif
 }
@@ -5980,16 +5996,16 @@ rb_stat_x(VALUE obj)
 
 #ifdef USE_GETEUID
     if (geteuid() == 0) {
-	return RBOOL(st->st_mode & S_IXUGO);
+        return RBOOL(st->st_mode & S_IXUGO);
     }
 #endif
 #ifdef S_IXUSR
     if (rb_stat_owned(obj))
-	return RBOOL(st->st_mode & S_IXUSR);
+        return RBOOL(st->st_mode & S_IXUSR);
 #endif
 #ifdef S_IXGRP
     if (rb_stat_grpowned(obj))
-	return RBOOL(st->st_mode & S_IXGRP);
+        return RBOOL(st->st_mode & S_IXGRP);
 #endif
 #ifdef S_IXOTH
     if (!(st->st_mode & S_IXOTH)) return Qfalse;
@@ -6012,16 +6028,16 @@ rb_stat_X(VALUE obj)
 
 #ifdef USE_GETEUID
     if (getuid() == 0) {
-	return RBOOL(st->st_mode & S_IXUGO);
+        return RBOOL(st->st_mode & S_IXUGO);
     }
 #endif
 #ifdef S_IXUSR
     if (rb_stat_rowned(obj))
-	return RBOOL(st->st_mode & S_IXUSR);
+        return RBOOL(st->st_mode & S_IXUSR);
 #endif
 #ifdef S_IXGRP
     if (rb_group_member(get_stat(obj)->st_gid))
-	return RBOOL(st->st_mode & S_IXGRP);
+        return RBOOL(st->st_mode & S_IXGRP);
 #endif
 #ifdef S_IXOTH
     if (!(st->st_mode & S_IXOTH)) return Qfalse;
@@ -6080,7 +6096,7 @@ rb_stat_z(VALUE obj)
 static VALUE
 rb_stat_s(VALUE obj)
 {
-    off_t size = get_stat(obj)->st_size;
+    rb_off_t size = get_stat(obj)->st_size;
 
     if (size == 0) return Qnil;
     return OFFT2NUM(size);
@@ -6186,14 +6202,14 @@ rb_file_s_mkfifo(int argc, VALUE *argv, VALUE _)
     ma.mode = 0666;
     rb_check_arity(argc, 1, 2);
     if (argc > 1) {
-	ma.mode = NUM2MODET(argv[1]);
+        ma.mode = NUM2MODET(argv[1]);
     }
     path = argv[0];
     FilePathValue(path);
     path = rb_str_encode_ospath(path);
     ma.path = RSTRING_PTR(path);
     if (rb_thread_call_without_gvl(nogvl_mkfifo, &ma, RUBY_UBF_IO, 0)) {
-	rb_sys_fail_path(path);
+        rb_sys_fail_path(path);
     }
     return INT2FIX(0);
 }
@@ -6243,16 +6259,16 @@ path_check_0(VALUE path)
     char *p = 0, *s;
 
     if (!rb_is_absolute_path(p0)) {
-	char *buf = ruby_getcwd();
-	VALUE newpath;
+        char *buf = ruby_getcwd();
+        VALUE newpath;
 
-	newpath = rb_str_new2(buf);
-	xfree(buf);
+        newpath = rb_str_new2(buf);
+        xfree(buf);
 
-	rb_str_cat2(newpath, "/");
-	rb_str_cat2(newpath, p0);
-	path = newpath;
-	p0 = RSTRING_PTR(path);
+        rb_str_cat2(newpath, "/");
+        rb_str_cat2(newpath, p0);
+        path = newpath;
+        p0 = RSTRING_PTR(path);
     }
     e0 = p0 + RSTRING_LEN(path);
     enc = rb_enc_get(path);
@@ -6260,28 +6276,28 @@ path_check_0(VALUE path)
 #ifndef S_IWOTH
 # define S_IWOTH 002
 #endif
-	if (STAT(p0, &st) == 0 && S_ISDIR(st.st_mode) && (st.st_mode & S_IWOTH)
+        if (STAT(p0, &st) == 0 && S_ISDIR(st.st_mode) && (st.st_mode & S_IWOTH)
 #ifdef S_ISVTX
-	    && !(p && (st.st_mode & S_ISVTX))
+            && !(p && (st.st_mode & S_ISVTX))
 #endif
-	    && !access(p0, W_OK)) {
-	    rb_enc_warn(enc, "Insecure world writable dir %s in PATH, mode 0%"
+            && !access(p0, W_OK)) {
+            rb_enc_warn(enc, "Insecure world writable dir %s in PATH, mode 0%"
 #if SIZEOF_DEV_T > SIZEOF_INT
-			PRI_MODET_PREFIX"o",
+                        PRI_MODET_PREFIX"o",
 #else
-			"o",
+                        "o",
 #endif
-			p0, st.st_mode);
-	    if (p) *p = '/';
-	    RB_GC_GUARD(path);
-	    return 0;
-	}
-	s = strrdirsep(p0, e0, enc);
-	if (p) *p = '/';
-	if (!s || s == p0) return 1;
-	p = s;
-	e0 = p;
-	*p = '\0';
+                        p0, st.st_mode);
+            if (p) *p = '/';
+            RB_GC_GUARD(path);
+            return 0;
+        }
+        s = strrdirsep(p0, e0, enc);
+        if (p) *p = '/';
+        if (!s || s == p0) return 1;
+        p = s;
+        e0 = p;
+        *p = '\0';
     }
 }
 #endif
@@ -6301,13 +6317,13 @@ rb_path_check(const char *path)
     if (!p) p = pend;
 
     for (;;) {
-	if (!path_check_0(rb_str_new(p0, p - p0))) {
-	    return 0;		/* not safe */
-	}
-	p0 = p + 1;
-	if (p0 > pend) break;
-	p = strchr(p0, sep);
-	if (!p) p = pend;
+        if (!path_check_0(rb_str_new(p0, p - p0))) {
+            return 0;		/* not safe */
+        }
+        p0 = p + 1;
+        if (p0 > pend) break;
+        p = strchr(p0, sep);
+        if (!p) p = pend;
     }
 #endif
     return 1;
@@ -6322,18 +6338,18 @@ ruby_is_fd_loadable(int fd)
     struct stat st;
 
     if (fstat(fd, &st) < 0)
-	return 0;
+        return 0;
 
     if (S_ISREG(st.st_mode))
-	return 1;
+        return 1;
 
     if (S_ISFIFO(st.st_mode) || S_ISCHR(st.st_mode))
-	return -1;
+        return -1;
 
     if (S_ISDIR(st.st_mode))
-	errno = EISDIR;
+        errno = EISDIR;
     else
-	errno = ENXIO;
+        errno = ENXIO;
 
     return 0;
 #endif
@@ -6350,11 +6366,11 @@ rb_file_load_ok(const char *path)
     */
     int mode = (O_RDONLY |
 #if defined O_NONBLOCK
-		O_NONBLOCK |
+                O_NONBLOCK |
 #elif defined O_NDELAY
-		O_NDELAY |
+                O_NDELAY |
 #endif
-		0);
+                0);
     int fd = rb_cloexec_open(path, mode, 0);
     if (fd == -1) return 0;
     rb_update_max_fd(fd);
@@ -6376,7 +6392,7 @@ static VALUE
 copy_path_class(VALUE path, VALUE orig)
 {
     int encidx = rb_enc_get_index(orig);
-    if (encidx == ENCINDEX_ASCII || encidx == ENCINDEX_US_ASCII)
+    if (encidx == ENCINDEX_ASCII_8BIT || encidx == ENCINDEX_US_ASCII)
         encidx = rb_filesystem_encindex();
     rb_enc_associate_index(path, encidx);
     str_shrink(path);
@@ -6396,24 +6412,24 @@ rb_find_file_ext(VALUE *filep, const char *const *ext)
     if (!ext[0]) return 0;
 
     if (f[0] == '~') {
-	fname = file_expand_path_1(fname);
-	f = RSTRING_PTR(fname);
-	*filep = fname;
-	expanded = 1;
+        fname = file_expand_path_1(fname);
+        f = RSTRING_PTR(fname);
+        *filep = fname;
+        expanded = 1;
     }
 
     if (expanded || rb_is_absolute_path(f) || is_explicit_relative(f)) {
-	if (!expanded) fname = file_expand_path_1(fname);
-	fnlen = RSTRING_LEN(fname);
-	for (i=0; ext[i]; i++) {
-	    rb_str_cat2(fname, ext[i]);
-	    if (rb_file_load_ok(RSTRING_PTR(fname))) {
-		*filep = copy_path_class(fname, *filep);
-		return (int)(i+1);
-	    }
-	    rb_str_set_len(fname, fnlen);
-	}
-	return 0;
+        if (!expanded) fname = file_expand_path_1(fname);
+        fnlen = RSTRING_LEN(fname);
+        for (i=0; ext[i]; i++) {
+            rb_str_cat2(fname, ext[i]);
+            if (rb_file_load_ok(RSTRING_PTR(fname))) {
+                *filep = copy_path_class(fname, *filep);
+                return (int)(i+1);
+            }
+            rb_str_set_len(fname, fnlen);
+        }
+        return 0;
     }
 
     RB_GC_GUARD(load_path) = rb_get_expanded_load_path();
@@ -6425,19 +6441,19 @@ rb_find_file_ext(VALUE *filep, const char *const *ext)
     tmp = rb_str_tmp_new(MAXPATHLEN + 2);
     rb_enc_associate_index(tmp, rb_usascii_encindex());
     for (j=0; ext[j]; j++) {
-	rb_str_cat2(fname, ext[j]);
-	for (i = 0; i < RARRAY_LEN(load_path); i++) {
-	    VALUE str = RARRAY_AREF(load_path, i);
+        rb_str_cat2(fname, ext[j]);
+        for (i = 0; i < RARRAY_LEN(load_path); i++) {
+            VALUE str = RARRAY_AREF(load_path, i);
 
             RB_GC_GUARD(str) = rb_get_path(str);
-	    if (RSTRING_LEN(str) == 0) continue;
-	    rb_file_expand_path_internal(fname, str, 0, 0, tmp);
-	    if (rb_file_load_ok(RSTRING_PTR(tmp))) {
-		*filep = copy_path_class(tmp, *filep);
-		return (int)(j+1);
-	    }
-	}
-	rb_str_set_len(fname, fnlen);
+            if (RSTRING_LEN(str) == 0) continue;
+            rb_file_expand_path_internal(fname, str, 0, 0, tmp);
+            if (rb_file_load_ok(RSTRING_PTR(tmp))) {
+                *filep = copy_path_class(tmp, *filep);
+                return (int)(j+1);
+            }
+        }
+        rb_str_set_len(fname, fnlen);
     }
     rb_str_resize(tmp, 0);
     RB_GC_GUARD(load_path);
@@ -6452,51 +6468,49 @@ rb_find_file(VALUE path)
     int expanded = 0;
 
     if (f[0] == '~') {
-	tmp = file_expand_path_1(path);
-	path = copy_path_class(tmp, path);
-	f = RSTRING_PTR(path);
-	expanded = 1;
+        tmp = file_expand_path_1(path);
+        path = copy_path_class(tmp, path);
+        f = RSTRING_PTR(path);
+        expanded = 1;
     }
 
     if (expanded || rb_is_absolute_path(f) || is_explicit_relative(f)) {
-	if (!rb_file_load_ok(f)) return 0;
-	if (!expanded)
-	    path = copy_path_class(file_expand_path_1(path), path);
-	return path;
+        if (!rb_file_load_ok(f)) return 0;
+        if (!expanded)
+            path = copy_path_class(file_expand_path_1(path), path);
+        return path;
     }
 
     RB_GC_GUARD(load_path) = rb_get_expanded_load_path();
     if (load_path) {
-	long i;
+        long i;
 
-	tmp = rb_str_tmp_new(MAXPATHLEN + 2);
-	rb_enc_associate_index(tmp, rb_usascii_encindex());
-	for (i = 0; i < RARRAY_LEN(load_path); i++) {
-	    VALUE str = RARRAY_AREF(load_path, i);
+        tmp = rb_str_tmp_new(MAXPATHLEN + 2);
+        rb_enc_associate_index(tmp, rb_usascii_encindex());
+        for (i = 0; i < RARRAY_LEN(load_path); i++) {
+            VALUE str = RARRAY_AREF(load_path, i);
             RB_GC_GUARD(str) = rb_get_path(str);
-	    if (RSTRING_LEN(str) > 0) {
-		rb_file_expand_path_internal(path, str, 0, 0, tmp);
-		f = RSTRING_PTR(tmp);
-		if (rb_file_load_ok(f)) goto found;
-	    }
-	}
-	rb_str_resize(tmp, 0);
-	return 0;
+            if (RSTRING_LEN(str) > 0) {
+                rb_file_expand_path_internal(path, str, 0, 0, tmp);
+                f = RSTRING_PTR(tmp);
+                if (rb_file_load_ok(f)) goto found;
+            }
+        }
+        rb_str_resize(tmp, 0);
+        return 0;
     }
     else {
-	return 0;		/* no path, no load */
+        return 0;		/* no path, no load */
     }
 
   found:
     return copy_path_class(tmp, path);
 }
 
-static void
-define_filetest_function(const char *name, VALUE (*func)(ANYARGS), int argc)
-{
-    rb_define_module_function(rb_mFileTest, name, func, argc);
-    rb_define_singleton_method(rb_cFile, name, func, argc);
-}
+#define define_filetest_function(name, func, argc) do {        \
+    rb_define_module_function(rb_mFileTest, name, func, argc); \
+    rb_define_singleton_method(rb_cFile, name, func, argc);    \
+} while(false)
 
 const char ruby_null_device[] =
 #if defined DOSISH
@@ -6516,6 +6530,602 @@ const char ruby_null_device[] =
  *  \Class \File extends module FileTest, supporting such singleton methods
  *  as <tt>File.exist?</tt>.
  *
+ *  === About the Examples
+ *
+ *  Many examples here use these variables:
+ *
+ *    :include: doc/examples/files.rdoc
+ *
+ *  == Access Modes
+ *
+ *  \Methods File.new and File.open each create a \File object for a given file path.
+ *
+ *  === \String Access Modes
+ *
+ *  \Methods File.new and File.open each may take string argument +mode+, which:
+ *
+ *  - Begins with a 1- or 2-character
+ *    {read/write mode}[rdoc-ref:File@Read-2FWrite+Mode].
+ *  - May also contain a 1-character {data mode}[rdoc-ref:File@Data+Mode].
+ *  - May also contain a 1-character
+ *    {file-create mode}[rdoc-ref:File@File-Create+Mode].
+ *
+ *  ==== Read/Write Mode
+ *
+ *  The read/write +mode+ determines:
+ *
+ *  - Whether the file is to be initially truncated.
+ *
+ *  - Whether reading is allowed, and if so:
+ *
+ *    - The initial read position in the file.
+ *    - Where in the file reading can occur.
+ *
+ *  - Whether writing is allowed, and if so:
+ *
+ *    - The initial write position in the file.
+ *    - Where in the file writing can occur.
+ *
+ *  These tables summarize:
+ *
+ *    Read/Write Modes for Existing File
+ *
+ *    |------|-----------|----------|----------|----------|-----------|
+ *    | R/W  | Initial   |          | Initial  |          | Initial   |
+ *    | Mode | Truncate? |  Read    | Read Pos |  Write   | Write Pos |
+ *    |------|-----------|----------|----------|----------|-----------|
+ *    | 'r'  |    No     | Anywhere |    0     |   Error  |     -     |
+ *    | 'w'  |    Yes    |   Error  |    -     | Anywhere |     0     |
+ *    | 'a'  |    No     |   Error  |    -     | End only |    End    |
+ *    | 'r+' |    No     | Anywhere |    0     | Anywhere |     0     |
+ *    | 'w+' |    Yes    | Anywhere |    0     | Anywhere |     0     |
+ *    | 'a+' |    No     | Anywhere |   End    | End only |    End    |
+ *    |------|-----------|----------|----------|----------|-----------|
+ *
+ *    Read/Write Modes for \File To Be Created
+ *
+ *    |------|----------|----------|----------|-----------|
+ *    | R/W  |          | Initial  |          | Initial   |
+ *    | Mode |  Read    | Read Pos |  Write   | Write Pos |
+ *    |------|----------|----------|----------|-----------|
+ *    | 'w'  |   Error  |    -     | Anywhere |     0     |
+ *    | 'a'  |   Error  |    -     | End only |     0     |
+ *    | 'w+' | Anywhere |    0     | Anywhere |     0     |
+ *    | 'a+' | Anywhere |    0     | End only |    End    |
+ *    |------|----------|----------|----------|-----------|
+ *
+ *  Note that modes <tt>'r'</tt> and <tt>'r+'</tt> are not allowed
+ *  for a non-existent file (exception raised).
+ *
+ *  In the tables:
+ *
+ *  - +Anywhere+ means that methods IO#rewind, IO#pos=, and IO#seek
+ *    may be used to change the file's position,
+ *    so that allowed reading or writing may occur anywhere in the file.
+ *  - <tt>End only</tt> means that writing can occur only at end-of-file,
+ *    and that methods IO#rewind, IO#pos=, and IO#seek do not affect writing.
+ *  - +Error+ means that an exception is raised if disallowed reading or writing
+ *    is attempted.
+ *
+ *  ===== Read/Write Modes for Existing \File
+ *
+ *  - <tt>'r'</tt>:
+ *
+ *    - File is not initially truncated:
+ *
+ *        f = File.new('t.txt') # => #<File:t.txt>
+ *        f.size == 0           # => false
+ *
+ *    - File's initial read position is 0:
+ *
+ *        f.pos # => 0
+ *
+ *    - File may be read anywhere; see IO#rewind, IO#pos=, IO#seek:
+ *
+ *        f.readline # => "First line\n"
+ *        f.readline # => "Second line\n"
+ *
+ *        f.rewind
+ *        f.readline # => "First line\n"
+ *
+ *        f.pos = 1
+ *        f.readline # => "irst line\n"
+ *
+ *        f.seek(1, :CUR)
+ *        f.readline # => "econd line\n"
+ *
+ *    - Writing is not allowed:
+ *
+ *        f.write('foo') # Raises IOError.
+ *
+ *  - <tt>'w'</tt>:
+ *
+ *    - File is initially truncated:
+ *
+ *        path = 't.tmp'
+ *        File.write(path, text)
+ *        f = File.new(path, 'w')
+ *        f.size == 0 # => true
+ *
+ *    - File's initial write position is 0:
+ *
+ *        f.pos # => 0
+ *
+ *    - File may be written anywhere (even past end-of-file);
+ *      see IO#rewind, IO#pos=, IO#seek:
+ *
+ *        f.write('foo')
+ *        f.flush
+ *        File.read(path) # => "foo"
+ *        f.pos # => 3
+ *
+ *        f.write('bar')
+ *        f.flush
+ *        File.read(path) # => "foobar"
+ *        f.pos # => 6
+ *
+ *        f.rewind
+ *        f.write('baz')
+ *        f.flush
+ *        File.read(path) # => "bazbar"
+ *        f.pos # => 3
+ *
+ *        f.pos = 3
+ *        f.write('foo')
+ *        f.flush
+ *        File.read(path) # => "bazfoo"
+ *        f.pos # => 6
+ *
+ *        f.seek(-3, :END)
+ *        f.write('bam')
+ *        f.flush
+ *        File.read(path) # => "bazbam"
+ *        f.pos # => 6
+ *
+ *        f.pos = 8
+ *        f.write('bah')  # Zero padding as needed.
+ *        f.flush
+ *        File.read(path) # => "bazbam\u0000\u0000bah"
+ *        f.pos # => 11
+ *
+ *    - Reading is not allowed:
+ *
+ *        f.read # Raises IOError.
+ *
+ *  - <tt>'a'</tt>:
+ *
+ *    - File is not initially truncated:
+ *
+ *        path = 't.tmp'
+ *        File.write(path, 'foo')
+ *        f = File.new(path, 'a')
+ *        f.size == 0 # => false
+ *
+ *    - File's initial position is 0 (but is ignored):
+ *
+ *        f.pos # => 0
+ *
+ *    - File may be written only at end-of-file;
+ *      IO#rewind, IO#pos=, IO#seek do not affect writing:
+ *
+ *        f.write('bar')
+ *        f.flush
+ *        File.read(path) # => "foobar"
+ *        f.write('baz')
+ *        f.flush
+ *        File.read(path) # => "foobarbaz"
+ *
+ *        f.rewind
+ *        f.write('bat')
+ *        f.flush
+ *        File.read(path) # => "foobarbazbat"
+ *
+ *    - Reading is not allowed:
+ *
+ *        f.read # Raises IOError.
+ *
+ *  - <tt>'r+'</tt>:
+ *
+ *    - File is not initially truncated:
+ *
+ *        path = 't.tmp'
+ *        File.write(path, text)
+ *        f = File.new(path, 'r+')
+ *        f.size == 0 # => false
+ *
+ *    - File's initial read position is 0:
+ *
+ *        f.pos # => 0
+ *
+ *    - File may be read or written anywhere (even past end-of-file);
+ *      see IO#rewind, IO#pos=, IO#seek:
+ *
+ *        f.readline # => "First line\n"
+ *        f.readline # => "Second line\n"
+ *
+ *        f.rewind
+ *        f.readline # => "First line\n"
+ *
+ *        f.pos = 1
+ *        f.readline # => "irst line\n"
+ *
+ *        f.seek(1, :CUR)
+ *        f.readline # => "econd line\n"
+ *
+ *        f.rewind
+ *        f.write('WWW')
+ *        f.flush
+ *        File.read(path)
+ *        # => "WWWst line\nSecond line\nFourth line\nFifth line\n"
+ *
+ *        f.pos = 10
+ *        f.write('XXX')
+ *        f.flush
+ *        File.read(path)
+ *        # => "WWWst lineXXXecond line\nFourth line\nFifth line\n"
+ *
+ *        f.seek(-6, :END)
+ *        # => 0
+ *        f.write('YYY')
+ *        # => 3
+ *        f.flush
+ *        # => #<File:t.tmp>
+ *        File.read(path)
+ *        # => "WWWst lineXXXecond line\nFourth line\nFifth YYYe\n"
+ *
+ *        f.seek(2, :END)
+ *        f.write('ZZZ') # Zero padding as needed.
+ *        f.flush
+ *        File.read(path)
+ *        # => "WWWst lineXXXecond line\nFourth line\nFifth YYYe\n\u0000\u0000ZZZ"
+ *
+ *
+ *  - <tt>'a+'</tt>:
+ *
+ *    - File is not initially truncated:
+ *
+ *        path = 't.tmp'
+ *        File.write(path, 'foo')
+ *        f = File.new(path, 'a+')
+ *        f.size == 0 # => false
+ *
+ *    - File's initial read position is 0:
+ *
+ *        f.pos # => 0
+ *
+ *    - File may be written only at end-of-file;
+ *      IO#rewind, IO#pos=, IO#seek do not affect writing:
+ *
+ *        f.write('bar')
+ *        f.flush
+ *        File.read(path)      # => "foobar"
+ *        f.write('baz')
+ *        f.flush
+ *        File.read(path)      # => "foobarbaz"
+ *
+ *        f.rewind
+ *        f.write('bat')
+ *        f.flush
+ *        File.read(path) # => "foobarbazbat"
+ *
+ *    - File may be read anywhere; see IO#rewind, IO#pos=, IO#seek:
+ *
+ *        f.rewind
+ *        f.read # => "foobarbazbat"
+ *
+ *        f.pos = 3
+ *        f.read # => "barbazbat"
+ *
+ *        f.seek(-3, :END)
+ *        f.read # => "bat"
+ *
+ *  ===== Read/Write Modes for \File To Be Created
+ *
+ *  Note that modes <tt>'r'</tt> and <tt>'r+'</tt> are not allowed
+ *  for a non-existent file (exception raised).
+ *
+ *  - <tt>'w'</tt>:
+ *
+ *    - File's initial write position is 0:
+ *
+ *        path = 't.tmp'
+ *        FileUtils.rm_f(path)
+ *        f = File.new(path, 'w')
+ *        f.pos # => 0
+ *
+ *    - File may be written anywhere (even past end-of-file);
+ *      see IO#rewind, IO#pos=, IO#seek:
+ *
+ *        f.write('foo')
+ *        f.flush
+ *        File.read(path) # => "foo"
+ *        f.pos # => 3
+ *
+ *        f.write('bar')
+ *        f.flush
+ *        File.read(path) # => "foobar"
+ *        f.pos # => 6
+ *
+ *        f.rewind
+ *        f.write('baz')
+ *        f.flush
+ *        File.read(path) # => "bazbar"
+ *        f.pos # => 3
+ *
+ *        f.pos = 3
+ *        f.write('foo')
+ *        f.flush
+ *        File.read(path) # => "bazfoo"
+ *        f.pos # => 6
+ *
+ *        f.seek(-3, :END)
+ *        f.write('bam')
+ *        f.flush
+ *        File.read(path) # => "bazbam"
+ *        f.pos # => 6
+ *
+ *        f.pos = 8
+ *        f.write('bah')  # Zero padding as needed.
+ *        f.flush
+ *        File.read(path) # => "bazbam\u0000\u0000bah"
+ *        f.pos # => 11
+ *
+ *    - Reading is not allowed:
+ *
+ *        f.read # Raises IOError.
+ *
+ *  - <tt>'a'</tt>:
+ *
+ *    - File's initial write position is 0:
+ *
+ *        path = 't.tmp'
+ *        FileUtils.rm_f(path)
+ *        f = File.new(path, 'a')
+ *        f.pos # => 0
+ *
+ *    - Writing occurs only at end-of-file:
+ *
+ *        f.write('foo')
+ *        f.pos # => 3
+ *        f.write('bar')
+ *        f.pos # => 6
+ *        f.flush
+ *        File.read(path) # => "foobar"
+ *
+ *        f.rewind
+ *        f.write('baz')
+ *        f.flush
+ *        File.read(path) # => "foobarbaz"
+ *
+ *    - Reading is not allowed:
+ *
+ *        f.read # Raises IOError.
+ *
+ *  - <tt>'w+'</tt>:
+ *
+ *    - File's initial position is 0:
+ *
+ *        path = 't.tmp'
+ *        FileUtils.rm_f(path)
+ *        f = File.new(path, 'w+')
+ *        f.pos # => 0
+ *
+ *    - File may be written anywhere (even past end-of-file);
+ *      see IO#rewind, IO#pos=, IO#seek:
+ *
+ *        f.write('foo')
+ *        f.flush
+ *        File.read(path) # => "foo"
+ *        f.pos # => 3
+ *
+ *        f.write('bar')
+ *        f.flush
+ *        File.read(path) # => "foobar"
+ *        f.pos # => 6
+ *
+ *        f.rewind
+ *        f.write('baz')
+ *        f.flush
+ *        File.read(path) # => "bazbar"
+ *        f.pos # => 3
+ *
+ *        f.pos = 3
+ *        f.write('foo')
+ *        f.flush
+ *        File.read(path) # => "bazfoo"
+ *        f.pos # => 6
+ *
+ *        f.seek(-3, :END)
+ *        f.write('bam')
+ *        f.flush
+ *        File.read(path) # => "bazbam"
+ *        f.pos # => 6
+ *
+ *        f.pos = 8
+ *        f.write('bah')  # Zero padding as needed.
+ *        f.flush
+ *        File.read(path) # => "bazbam\u0000\u0000bah"
+ *        f.pos # => 11
+ *
+ *    - File may be read anywhere (even past end-of-file);
+ *      see IO#rewind, IO#pos=, IO#seek:
+ *
+ *        f.rewind
+ *        # => 0
+ *        f.read
+ *        # => "bazbam\u0000\u0000bah"
+ *
+ *        f.pos = 3
+ *        # => 3
+ *        f.read
+ *        # => "bam\u0000\u0000bah"
+ *
+ *        f.seek(-3, :END)
+ *        # => 0
+ *        f.read
+ *        # => "bah"
+ *
+ *  - <tt>'a+'</tt>:
+ *
+ *    - File's initial write position is 0:
+ *
+ *        path = 't.tmp'
+ *        FileUtils.rm_f(path)
+ *        f = File.new(path, 'a+')
+ *        f.pos # => 0
+ *
+ *    - Writing occurs only at end-of-file:
+ *
+ *        f.write('foo')
+ *        f.pos # => 3
+ *        f.write('bar')
+ *        f.pos # => 6
+ *        f.flush
+ *        File.read(path) # => "foobar"
+ *
+ *        f.rewind
+ *        f.write('baz')
+ *        f.flush
+ *        File.read(path) # => "foobarbaz"
+ *
+ *    - File may be read anywhere (even past end-of-file);
+ *      see IO#rewind, IO#pos=, IO#seek:
+ *
+ *        f.rewind
+ *        f.read # => "foobarbaz"
+ *
+ *        f.pos = 3
+ *        f.read # => "barbaz"
+ *
+ *        f.seek(-3, :END)
+ *        f.read # => "baz"
+ *
+ *        f.pos = 800
+ *        f.read # => ""
+ *
+ *  ==== \Data Mode
+ *
+ *  To specify whether data is to be treated as text or as binary data,
+ *  either of the following may be suffixed to any of the string read/write modes
+ *  above:
+ *
+ *  - <tt>'t'</tt>: Text data; sets the default external encoding
+ *    to <tt>Encoding::UTF_8</tt>;
+ *    on Windows, enables conversion between EOL and CRLF
+ *    and enables interpreting <tt>0x1A</tt> as an end-of-file marker.
+ *  - <tt>'b'</tt>: Binary data; sets the default external encoding
+ *    to <tt>Encoding::ASCII_8BIT</tt>;
+ *    on Windows, suppresses conversion between EOL and CRLF
+ *    and disables interpreting <tt>0x1A</tt> as an end-of-file marker.
+ *
+ *  If neither is given, the stream defaults to text data.
+ *
+ *  Examples:
+ *
+ *    File.new('t.txt', 'rt')
+ *    File.new('t.dat', 'rb')
+ *
+ *  When the data mode is specified, the read/write mode may not be omitted,
+ *  and the data mode must precede the file-create mode, if given:
+ *
+ *    File.new('t.dat', 'b')   # Raises an exception.
+ *    File.new('t.dat', 'rxb') # Raises an exception.
+ *
+ *  ==== \File-Create Mode
+ *
+ *  The following may be suffixed to any writable string mode above:
+ *
+ *  - <tt>'x'</tt>: Creates the file if it does not exist;
+ *    raises an exception if the file exists.
+ *
+ *  Example:
+ *
+ *    File.new('t.tmp', 'wx')
+ *
+ *  When the file-create mode is specified, the read/write mode may not be omitted,
+ *  and the file-create mode must follow the data mode:
+ *
+ *    File.new('t.dat', 'x')   # Raises an exception.
+ *    File.new('t.dat', 'rxb') # Raises an exception.
+ *
+ *  === \Integer Access Modes
+ *
+ *  When mode is an integer it must be one or more of the following constants,
+ *  which may be combined by the bitwise OR operator <tt>|</tt>:
+ *
+ *  - +File::RDONLY+: Open for reading only.
+ *  - +File::WRONLY+: Open for writing only.
+ *  - +File::RDWR+: Open for reading and writing.
+ *  - +File::APPEND+: Open for appending only.
+ *
+ *  Examples:
+ *
+ *    File.new('t.txt', File::RDONLY)
+ *    File.new('t.tmp', File::RDWR | File::CREAT | File::EXCL)
+ *
+ *  Note: Method IO#set_encoding does not allow the mode to be specified as an integer.
+ *
+ *  === File-Create Mode Specified as an \Integer
+ *
+ *  These constants may also be ORed into the integer mode:
+ *
+ *  - +File::CREAT+: Create file if it does not exist.
+ *  - +File::EXCL+: Raise an exception if +File::CREAT+ is given and the file exists.
+ *
+ *  === \Data Mode Specified as an \Integer
+ *
+ *  \Data mode cannot be specified as an integer.
+ *  When the stream access mode is given as an integer,
+ *  the data mode is always text, never binary.
+ *
+ *  Note that although there is a constant +File::BINARY+,
+ *  setting its value in an integer stream mode has no effect;
+ *  this is because, as documented in File::Constants,
+ *  the +File::BINARY+ value disables line code conversion,
+ *  but does not change the external encoding.
+ *
+ *  === Encodings
+ *
+ *  Any of the string modes above may specify encodings -
+ *  either external encoding only or both external and internal encodings -
+ *  by appending one or both encoding names, separated by colons:
+ *
+ *    f = File.new('t.dat', 'rb')
+ *    f.external_encoding # => #<Encoding:ASCII-8BIT>
+ *    f.internal_encoding # => nil
+ *    f = File.new('t.dat', 'rb:UTF-16')
+ *    f.external_encoding # => #<Encoding:UTF-16 (dummy)>
+ *    f.internal_encoding # => nil
+ *    f = File.new('t.dat', 'rb:UTF-16:UTF-16')
+ *    f.external_encoding # => #<Encoding:UTF-16 (dummy)>
+ *    f.internal_encoding # => #<Encoding:UTF-16>
+ *    f.close
+ *
+ *  The numerous encoding names are available in array Encoding.name_list:
+ *
+ *    Encoding.name_list.take(3) # => ["ASCII-8BIT", "UTF-8", "US-ASCII"]
+ *
+ *  When the external encoding is set, strings read are tagged by that encoding
+ *  when reading, and strings written are converted to that encoding when
+ *  writing.
+ *
+ *  When both external and internal encodings are set,
+ *  strings read are converted from external to internal encoding,
+ *  and strings written are converted from internal to external encoding.
+ *  For further details about transcoding input and output,
+ *  see {Encodings}[rdoc-ref:encodings.rdoc@Encodings].
+ *
+ *  If the external encoding is <tt>'BOM|UTF-8'</tt>, <tt>'BOM|UTF-16LE'</tt>
+ *  or <tt>'BOM|UTF16-BE'</tt>,
+ *  Ruby checks for a Unicode BOM in the input document
+ *  to help determine the encoding.
+ *  For UTF-16 encodings the file open mode must be binary.
+ *  If the BOM is found,
+ *  it is stripped and the external encoding from the BOM is used.
+ *
+ *  Note that the BOM-style encoding option is case insensitive,
+ *  so <tt>'bom|utf-8'</tt> is also valid.
+ *
  *  == \File Permissions
  *
  *  A \File object has _permissions_, an octal integer representing
@@ -6567,7 +7177,7 @@ const char ruby_null_device[] =
  *    f.chmod(0644)
  *    f.chmod(0444)
  *
- *  == \File Constants
+ *  == \File \Constants
  *
  *  Various constants for use in \File and \IO methods
  *  may be found in module File::Constants;
@@ -6639,7 +7249,7 @@ const char ruby_null_device[] =
  *
  *  - ::blockdev?: Returns whether the file at the given path is a block device.
  *  - ::chardev?: Returns whether the file at the given path is a character device.
- *  - ::directory?: Returns whether the file at the given path is a diretory.
+ *  - ::directory?: Returns whether the file at the given path is a directory.
  *  - ::executable?: Returns whether the file at the given path is executable
  *    by the effective user and group of the current process.
  *  - ::executable_real?: Returns whether the file at the given path is executable
@@ -6710,6 +7320,10 @@ const char ruby_null_device[] =
 void
 Init_File(void)
 {
+#if defined(__APPLE__) && defined(HAVE_WORKING_FORK)
+    rb_CFString_class_initialize_before_fork();
+#endif
+
     VALUE separator;
 
     rb_mFileTest = rb_define_module("FileTest");
@@ -6906,8 +7520,6 @@ Init_File(void)
     /* Name of the null device */
     rb_define_const(rb_mFConst, "NULL", rb_fstring_cstr(ruby_null_device));
 
-    rb_define_method(rb_cFile, "path",  rb_file_path, 0);
-    rb_define_method(rb_cFile, "to_path",  rb_file_path, 0);
     rb_define_global_function("test", rb_f_test, -1);
 
     rb_cStat = rb_define_class_under(rb_cFile, "Stat", rb_cObject);
diff --git a/gc.c b/gc.c
index 2a2d1a169a..919d57989a 100644
--- a/gc.c
+++ b/gc.c
@@ -87,6 +87,11 @@
 #include <emscripten.h>
 #endif
 
+#ifdef HAVE_MACH_TASK_EXCEPTION_PORTS
+# include <mach/task.h>
+# include <mach/mach_init.h>
+# include <mach/mach_port.h>
+#endif
 #undef LIST_HEAD /* ccan/list conflicts with BSD-origin sys/queue.h. */
 
 #include "constant.h"
@@ -133,6 +138,7 @@
 #include "ractor_core.h"
 
 #include "builtin.h"
+#include "shape.h"
 
 #define rb_setjmp(env) RUBY_SETJMP(env)
 #define rb_jmp_buf rb_jmpbuf_t
@@ -568,64 +574,77 @@ struct RMoved {
     VALUE flags;
     VALUE dummy;
     VALUE destination;
+    shape_id_t original_shape_id;
 };
 
 #define RMOVED(obj) ((struct RMoved *)(obj))
 
 typedef struct RVALUE {
     union {
-	struct {
-	    VALUE flags;		/* always 0 for freed obj */
-	    struct RVALUE *next;
-	} free;
+        struct {
+            VALUE flags;		/* always 0 for freed obj */
+            struct RVALUE *next;
+        } free;
         struct RMoved  moved;
-	struct RBasic  basic;
-	struct RObject object;
-	struct RClass  klass;
-	struct RFloat  flonum;
-	struct RString string;
-	struct RArray  array;
-	struct RRegexp regexp;
-	struct RHash   hash;
-	struct RData   data;
-	struct RTypedData   typeddata;
-	struct RStruct rstruct;
-	struct RBignum bignum;
-	struct RFile   file;
-	struct RMatch  match;
-	struct RRational rational;
-	struct RComplex complex;
+        struct RBasic  basic;
+        struct RObject object;
+        struct RClass  klass;
+        struct RFloat  flonum;
+        struct RString string;
+        struct RArray  array;
+        struct RRegexp regexp;
+        struct RHash   hash;
+        struct RData   data;
+        struct RTypedData   typeddata;
+        struct RStruct rstruct;
+        struct RBignum bignum;
+        struct RFile   file;
+        struct RMatch  match;
+        struct RRational rational;
+        struct RComplex complex;
         struct RSymbol symbol;
-	union {
-	    rb_cref_t cref;
-	    struct vm_svar svar;
-	    struct vm_throw_data throw_data;
-	    struct vm_ifunc ifunc;
-	    struct MEMO memo;
-	    struct rb_method_entry_struct ment;
-	    const rb_iseq_t iseq;
-	    rb_env_t env;
-	    struct rb_imemo_tmpbuf_struct alloc;
-	    rb_ast_t ast;
-	} imemo;
-	struct {
-	    struct RBasic basic;
-	    VALUE v1;
-	    VALUE v2;
-	    VALUE v3;
-	} values;
+        union {
+            rb_cref_t cref;
+            struct vm_svar svar;
+            struct vm_throw_data throw_data;
+            struct vm_ifunc ifunc;
+            struct MEMO memo;
+            struct rb_method_entry_struct ment;
+            const rb_iseq_t iseq;
+            rb_env_t env;
+            struct rb_imemo_tmpbuf_struct alloc;
+            rb_ast_t ast;
+        } imemo;
+        struct {
+            struct RBasic basic;
+            VALUE v1;
+            VALUE v2;
+            VALUE v3;
+        } values;
     } as;
+
+    /* Start of RVALUE_OVERHEAD.
+     * Do not directly read these members from the RVALUE as they're located
+     * at the end of the slot (which may differ in size depending on the size
+     * pool). */
+#if RACTOR_CHECK_MODE
+    uint32_t _ractor_belonging_id;
+#endif
 #if GC_DEBUG
     const char *file;
     int line;
 #endif
 } RVALUE;
 
-#if GC_DEBUG
-STATIC_ASSERT(sizeof_rvalue, offsetof(RVALUE, file) == SIZEOF_VALUE * 5);
+#if RACTOR_CHECK_MODE
+# define RVALUE_OVERHEAD (sizeof(RVALUE) - offsetof(RVALUE, _ractor_belonging_id))
+#elif GC_DEBUG
+# define RVALUE_OVERHEAD (sizeof(RVALUE) - offsetof(RVALUE, file))
 #else
-STATIC_ASSERT(sizeof_rvalue, sizeof(RVALUE) == SIZEOF_VALUE * 5);
+# define RVALUE_OVERHEAD 0
 #endif
+
+STATIC_ASSERT(sizeof_rvalue, sizeof(RVALUE) == (SIZEOF_VALUE * 5) + RVALUE_OVERHEAD);
 STATIC_ASSERT(alignof_rvalue, RUBY_ALIGNOF(RVALUE) == SIZEOF_VALUE);
 
 typedef uintptr_t bits_t;
@@ -690,14 +709,12 @@ typedef struct rb_size_pool_struct {
     /* Basic statistics */
     size_t total_allocated_pages;
     size_t total_freed_pages;
+    size_t force_major_gc_count;
 
 #if USE_RVARGC
     /* Sweeping statistics */
     size_t freed_slots;
     size_t empty_slots;
-
-    /* Global statistics */
-    size_t force_major_gc_count;
 #endif
 
     rb_heap_t eden_heap;
@@ -713,27 +730,27 @@ enum gc_mode {
 
 typedef struct rb_objspace {
     struct {
-	size_t limit;
-	size_t increase;
+        size_t limit;
+        size_t increase;
 #if MALLOC_ALLOCATED_SIZE
-	size_t allocated_size;
-	size_t allocations;
+        size_t allocated_size;
+        size_t allocations;
 #endif
 
     } malloc_params;
 
     struct {
-	unsigned int mode : 2;
-	unsigned int immediate_sweep : 1;
-	unsigned int dont_gc : 1;
-	unsigned int dont_incremental : 1;
-	unsigned int during_gc : 1;
+        unsigned int mode : 2;
+        unsigned int immediate_sweep : 1;
+        unsigned int dont_gc : 1;
+        unsigned int dont_incremental : 1;
+        unsigned int during_gc : 1;
         unsigned int during_compacting : 1;
-	unsigned int gc_stressful: 1;
-	unsigned int has_hook: 1;
-	unsigned int during_minor_gc : 1;
+        unsigned int gc_stressful: 1;
+        unsigned int has_hook: 1;
+        unsigned int during_minor_gc : 1;
 #if GC_ENABLE_INCREMENTAL_MARK
-	unsigned int during_incremental_marking : 1;
+        unsigned int during_incremental_marking : 1;
 #endif
         unsigned int measure_gc : 1;
     } flags;
@@ -745,70 +762,70 @@ typedef struct rb_objspace {
     rb_size_pool_t size_pools[SIZE_POOL_COUNT];
 
     struct {
-	rb_atomic_t finalizing;
+        rb_atomic_t finalizing;
     } atomic_flags;
 
     mark_stack_t mark_stack;
     size_t marked_slots;
 
     struct {
-	struct heap_page **sorted;
-	size_t allocated_pages;
-	size_t allocatable_pages;
-	size_t sorted_length;
-	uintptr_t range[2];
-	size_t freeable_pages;
-
-	/* final */
-	size_t final_slots;
-	VALUE deferred_final;
+        struct heap_page **sorted;
+        size_t allocated_pages;
+        size_t allocatable_pages;
+        size_t sorted_length;
+        uintptr_t range[2];
+        size_t freeable_pages;
+
+        /* final */
+        size_t final_slots;
+        VALUE deferred_final;
     } heap_pages;
 
     st_table *finalizer_table;
 
     struct {
-	int run;
-	unsigned int latest_gc_info;
-	gc_profile_record *records;
-	gc_profile_record *current_record;
-	size_t next_index;
-	size_t size;
+        int run;
+        unsigned int latest_gc_info;
+        gc_profile_record *records;
+        gc_profile_record *current_record;
+        size_t next_index;
+        size_t size;
 
 #if GC_PROFILE_MORE_DETAIL
-	double prepare_time;
+        double prepare_time;
 #endif
-	double invoke_time;
+        double invoke_time;
 
-	size_t minor_gc_count;
-	size_t major_gc_count;
-	size_t compact_count;
-	size_t read_barrier_faults;
+        size_t minor_gc_count;
+        size_t major_gc_count;
+        size_t compact_count;
+        size_t read_barrier_faults;
 #if RGENGC_PROFILE > 0
-	size_t total_generated_normal_object_count;
-	size_t total_generated_shady_object_count;
-	size_t total_shade_operation_count;
-	size_t total_promoted_count;
-	size_t total_remembered_normal_object_count;
-	size_t total_remembered_shady_object_count;
+        size_t total_generated_normal_object_count;
+        size_t total_generated_shady_object_count;
+        size_t total_shade_operation_count;
+        size_t total_promoted_count;
+        size_t total_remembered_normal_object_count;
+        size_t total_remembered_shady_object_count;
 
 #if RGENGC_PROFILE >= 2
-	size_t generated_normal_object_count_types[RUBY_T_MASK];
-	size_t generated_shady_object_count_types[RUBY_T_MASK];
-	size_t shade_operation_count_types[RUBY_T_MASK];
-	size_t promoted_types[RUBY_T_MASK];
-	size_t remembered_normal_object_count_types[RUBY_T_MASK];
-	size_t remembered_shady_object_count_types[RUBY_T_MASK];
+        size_t generated_normal_object_count_types[RUBY_T_MASK];
+        size_t generated_shady_object_count_types[RUBY_T_MASK];
+        size_t shade_operation_count_types[RUBY_T_MASK];
+        size_t promoted_types[RUBY_T_MASK];
+        size_t remembered_normal_object_count_types[RUBY_T_MASK];
+        size_t remembered_shady_object_count_types[RUBY_T_MASK];
 #endif
 #endif /* RGENGC_PROFILE */
 
-	/* temporary profiling space */
-	double gc_sweep_start_time;
-	size_t total_allocated_objects_at_gc_start;
-	size_t heap_used_at_gc_start;
+        /* temporary profiling space */
+        double gc_sweep_start_time;
+        size_t total_allocated_objects_at_gc_start;
+        size_t heap_used_at_gc_start;
 
-	/* basic statistics */
-	size_t count;
-	size_t total_freed_objects;
+        /* basic statistics */
+        size_t count;
+        size_t total_freed_objects;
         uint64_t total_time_ns;
         struct timespec start_time;
     } profile;
@@ -817,35 +834,37 @@ typedef struct rb_objspace {
     VALUE gc_stress_mode;
 
     struct {
-	VALUE parent_object;
-	int need_major_gc;
-	size_t last_major_gc;
-	size_t uncollectible_wb_unprotected_objects;
-	size_t uncollectible_wb_unprotected_objects_limit;
-	size_t old_objects;
-	size_t old_objects_limit;
+        VALUE parent_object;
+        int need_major_gc;
+        size_t last_major_gc;
+        size_t uncollectible_wb_unprotected_objects;
+        size_t uncollectible_wb_unprotected_objects_limit;
+        size_t old_objects;
+        size_t old_objects_limit;
 
 #if RGENGC_ESTIMATE_OLDMALLOC
-	size_t oldmalloc_increase;
-	size_t oldmalloc_increase_limit;
+        size_t oldmalloc_increase;
+        size_t oldmalloc_increase_limit;
 #endif
 
 #if RGENGC_CHECK_MODE >= 2
-	struct st_table *allrefs_table;
-	size_t error_count;
+        struct st_table *allrefs_table;
+        size_t error_count;
 #endif
     } rgengc;
 
     struct {
         size_t considered_count_table[T_MASK];
         size_t moved_count_table[T_MASK];
+        size_t moved_up_count_table[T_MASK];
+        size_t moved_down_count_table[T_MASK];
         size_t total_moved;
     } rcompactor;
 
 #if GC_ENABLE_INCREMENTAL_MARK
     struct {
-	size_t pooled_slots;
-	size_t step_slots;
+        size_t pooled_slots;
+        size_t step_slots;
     } rincgc;
 #endif
 
@@ -865,7 +884,7 @@ typedef struct rb_objspace {
 
 #define BASE_SLOT_SIZE sizeof(RVALUE)
 
-#define CEILDIV(i, mod) (((i) + (mod) - 1)/(mod))
+#define CEILDIV(i, mod) roomof(i, mod)
 enum {
     HEAP_PAGE_ALIGN = (1UL << HEAP_PAGE_ALIGN_LOG),
     HEAP_PAGE_ALIGN_MASK = (~(~0UL << HEAP_PAGE_ALIGN_LOG)),
@@ -881,39 +900,58 @@ enum {
 # define INCREMENTAL_MARK_STEP_ALLOCATIONS 500
 #endif
 
-#ifdef HAVE_MMAP
+#undef INIT_HEAP_PAGE_ALLOC_USE_MMAP
+/* Must define either HEAP_PAGE_ALLOC_USE_MMAP or
+ * INIT_HEAP_PAGE_ALLOC_USE_MMAP. */
+
+#ifndef HAVE_MMAP
+/* We can't use mmap of course, if it is not available. */
+static const bool HEAP_PAGE_ALLOC_USE_MMAP = false;
+
+#elif defined(__wasm__)
 /* wasmtime does not have proper support for mmap.
  * See https://github.com/bytecodealliance/wasmtime/blob/main/docs/WASI-rationale.md#why-no-mmap-and-friends
  */
-# if defined(__wasm__)
 static const bool HEAP_PAGE_ALLOC_USE_MMAP = false;
-# elif HAVE_CONST_PAGE_SIZE
-/* If we have the HEAP_PAGE and it is a constant, then we can directly use it. */
+
+#elif HAVE_CONST_PAGE_SIZE
+/* If we have the PAGE_SIZE and it is a constant, then we can directly use it. */
 static const bool HEAP_PAGE_ALLOC_USE_MMAP = (PAGE_SIZE <= HEAP_PAGE_SIZE);
-# elif defined(PAGE_MAX_SIZE) && (PAGE_MAX_SIZE <= HEAP_PAGE_SIZE)
-/* PAGE_SIZE <= HEAP_PAGE_SIZE */
+
+#elif defined(PAGE_MAX_SIZE) && (PAGE_MAX_SIZE <= HEAP_PAGE_SIZE)
+/* If we can use the maximum page size. */
 static const bool HEAP_PAGE_ALLOC_USE_MMAP = true;
-# else
-/* Otherwise, fall back to determining if we can use mmap during runtime. */
-#  define HEAP_PAGE_ALLOC_USE_MMAP (heap_page_alloc_use_mmap != false)
 
-static bool heap_page_alloc_use_mmap;
-# endif
-#elif !defined(__MINGW32__) && !defined(_WIN32)
+#elif defined(PAGE_SIZE)
+/* If the PAGE_SIZE macro can be used dynamically. */
+# define INIT_HEAP_PAGE_ALLOC_USE_MMAP (PAGE_SIZE <= HEAP_PAGE_SIZE)
+
+#elif defined(HAVE_SYSCONF) && defined(_SC_PAGE_SIZE)
+/* If we can use sysconf to determine the page size. */
+# define INIT_HEAP_PAGE_ALLOC_USE_MMAP (sysconf(_SC_PAGE_SIZE) <= HEAP_PAGE_SIZE)
+
+#else
+/* Otherwise we can't determine the system page size, so don't use mmap. */
 static const bool HEAP_PAGE_ALLOC_USE_MMAP = false;
 #endif
 
+#ifdef INIT_HEAP_PAGE_ALLOC_USE_MMAP
+/* We can determine the system page size at runtime. */
+# define HEAP_PAGE_ALLOC_USE_MMAP (heap_page_alloc_use_mmap != false)
+
+static bool heap_page_alloc_use_mmap;
+#endif
+
 struct heap_page {
     short slot_size;
     short total_slots;
     short free_slots;
-    short pinned_slots;
     short final_slots;
     struct {
-	unsigned int before_sweep : 1;
-	unsigned int has_remembered_objects : 1;
-	unsigned int has_uncollectible_shady_objects : 1;
-	unsigned int in_tomb : 1;
+        unsigned int before_sweep : 1;
+        unsigned int has_remembered_objects : 1;
+        unsigned int has_uncollectible_shady_objects : 1;
+        unsigned int in_tomb : 1;
     } flags;
 
     rb_size_pool_t *size_pool;
@@ -933,6 +971,24 @@ struct heap_page {
     bits_t pinned_bits[HEAP_PAGE_BITMAP_LIMIT];
 };
 
+/*
+ * When asan is enabled, this will prohibit writing to the freelist until it is unlocked
+ */
+static void
+asan_lock_freelist(struct heap_page *page)
+{
+    asan_poison_memory_region(&page->freelist, sizeof(RVALUE*));
+}
+
+/*
+ * When asan is enabled, this will enable the ability to write to the freelist
+ */
+static void
+asan_unlock_freelist(struct heap_page *page)
+{
+    asan_unpoison_memory_region(&page->freelist, sizeof(RVALUE*), false);
+}
+
 #define GET_PAGE_BODY(x)   ((struct heap_page_body *)((bits_t)(x) & ~(HEAP_PAGE_ALIGN_MASK)))
 #define GET_PAGE_HEADER(x) (&GET_PAGE_BODY(x)->header)
 #define GET_HEAP_PAGE(x)   (GET_PAGE_HEADER(x)->page)
@@ -1009,9 +1065,9 @@ gc_mode_verify(enum gc_mode mode)
       case gc_mode_marking:
       case gc_mode_sweeping:
       case gc_mode_compacting:
-	break;
+        break;
       default:
-	rb_bug("gc_mode_verify: unreachable (%d)", (int)mode);
+        rb_bug("gc_mode_verify: unreachable (%d)", (int)mode);
     }
 #endif
     return mode;
@@ -1197,6 +1253,9 @@ static void gc_marks_continue(rb_objspace_t *objspace, rb_size_pool_t *size_pool
 
 static void gc_sweep(rb_objspace_t *objspace);
 static void gc_sweep_start(rb_objspace_t *objspace);
+#if USE_RVARGC
+static void gc_sweep_finish_size_pool(rb_objspace_t *objspace, rb_size_pool_t *size_pool);
+#endif
 static void gc_sweep_finish(rb_objspace_t *objspace);
 static int  gc_sweep_step(rb_objspace_t *objspace, rb_size_pool_t *size_pool, rb_heap_t *heap);
 static void gc_sweep_rest(rb_objspace_t *objspace);
@@ -1241,8 +1300,8 @@ static inline void gc_prof_set_malloc_info(rb_objspace_t *);
 static inline void gc_prof_set_heap_info(rb_objspace_t *);
 
 #define TYPED_UPDATE_IF_MOVED(_objspace, _type, _thing) do { \
-    if (gc_object_moved_p(_objspace, (VALUE)_thing)) { \
-       *((_type *)(&_thing)) = (_type)RMOVED((_thing))->destination; \
+    if (gc_object_moved_p((_objspace), (VALUE)(_thing))) {    \
+        *(_type *)&(_thing) = (_type)RMOVED(_thing)->destination; \
     } \
 } while (0)
 
@@ -1313,6 +1372,27 @@ tick(void)
     return val;
 }
 
+/* Implementation for macOS PPC by @nobu
+ * See: https://github.com/ruby/ruby/pull/5975#discussion_r890045558
+ */
+#elif defined(__POWERPC__) && defined(__APPLE__)
+typedef unsigned long long tick_t;
+#define PRItick "llu"
+
+static __inline__ tick_t
+tick(void)
+{
+    unsigned long int upper, lower, tmp;
+    # define mftbu(r) __asm__ volatile("mftbu   %0" : "=r"(r))
+    # define mftb(r)  __asm__ volatile("mftb    %0" : "=r"(r))
+        do {
+            mftbu(upper);
+            mftb(lower);
+            mftbu(tmp);
+        } while (tmp != upper);
+    return ((tick_t)upper << 32) | lower;
+}
+
 #elif defined(__aarch64__) &&  defined(__GNUC__)
 typedef unsigned long tick_t;
 #define PRItick "lu"
@@ -1381,6 +1461,21 @@ asan_unpoison_object_temporary(VALUE obj)
     return ptr;
 }
 
+static inline void *
+asan_poison_object_restore(VALUE obj, void *ptr)
+{
+    if (ptr) {
+        asan_poison_object(obj);
+    }
+    return NULL;
+}
+
+#define asan_unpoisoning_object(obj) \
+    for (void *poisoned = asan_unpoison_object_temporary(obj), \
+              *unpoisoning = &poisoned; /* flag to loop just once */ \
+         unpoisoning; \
+         unpoisoning = asan_poison_object_restore(obj, poisoned))
+
 #define FL_CHECK2(name, x, pred) \
     ((RGENGC_CHECK_MODE && SPECIAL_CONST_P(x)) ? \
      (rb_bug(name": SPECIAL_CONST (%p)", (void *)(x)), 0) : (pred))
@@ -1542,8 +1637,7 @@ gc_object_moved_p(rb_objspace_t * objspace, VALUE obj)
         return FALSE;
     }
     else {
-        void *poisoned = asan_poisoned_object_p(obj);
-        asan_unpoison_object(obj, false);
+        void *poisoned = asan_unpoison_object_temporary(obj);
 
         int ret =  BUILTIN_TYPE(obj) == T_MOVED;
         /* Re-poison slot if it's not the one we want */
@@ -1656,14 +1750,14 @@ RVALUE_AGE_INC(rb_objspace_t *objspace, VALUE obj)
     int age = RVALUE_FLAGS_AGE(flags);
 
     if (RGENGC_CHECK_MODE && age == RVALUE_OLD_AGE) {
-	rb_bug("RVALUE_AGE_INC: can not increment age of OLD object %s.", obj_info(obj));
+        rb_bug("RVALUE_AGE_INC: can not increment age of OLD object %s.", obj_info(obj));
     }
 
     age++;
     RBASIC(obj)->flags = RVALUE_FLAGS_AGE_SET(flags, age);
 
     if (age == RVALUE_OLD_AGE) {
-	RVALUE_OLD_UNCOLLECTIBLE_SET(objspace, obj);
+        RVALUE_OLD_UNCOLLECTIBLE_SET(objspace, obj);
     }
     check_rvalue_consistency(obj);
 }
@@ -1707,13 +1801,13 @@ RVALUE_DEMOTE(rb_objspace_t *objspace, VALUE obj)
     GC_ASSERT(RVALUE_OLD_P(obj));
 
     if (!is_incremental_marking(objspace) && RVALUE_REMEMBERED(obj)) {
-	CLEAR_IN_BITMAP(GET_HEAP_MARKING_BITS(obj), obj);
+        CLEAR_IN_BITMAP(GET_HEAP_MARKING_BITS(obj), obj);
     }
 
     RVALUE_DEMOTE_RAW(objspace, obj);
 
     if (RVALUE_MARKED(obj)) {
-	objspace->rgengc.old_objects--;
+        objspace->rgengc.old_objects--;
     }
 
     check_rvalue_consistency(obj);
@@ -1794,30 +1888,30 @@ void
 rb_objspace_free(rb_objspace_t *objspace)
 {
     if (is_lazy_sweeping(objspace))
-	rb_bug("lazy sweeping underway when freeing object space");
+        rb_bug("lazy sweeping underway when freeing object space");
 
     if (objspace->profile.records) {
-	free(objspace->profile.records);
-	objspace->profile.records = 0;
+        free(objspace->profile.records);
+        objspace->profile.records = 0;
     }
 
     if (global_list) {
-	struct gc_list *list, *next;
-	for (list = global_list; list; list = next) {
-	    next = list->next;
-	    xfree(list);
-	}
+        struct gc_list *list, *next;
+        for (list = global_list; list; list = next) {
+            next = list->next;
+            xfree(list);
+        }
     }
     if (heap_pages_sorted) {
-	size_t i;
-	for (i = 0; i < heap_allocated_pages; ++i) {
-	    heap_page_free(objspace, heap_pages_sorted[i]);
-	}
-	free(heap_pages_sorted);
-	heap_allocated_pages = 0;
-	heap_pages_sorted_length = 0;
-	heap_pages_lomem = 0;
-	heap_pages_himem = 0;
+        size_t i;
+        for (i = 0; i < heap_allocated_pages; ++i) {
+            heap_page_free(objspace, heap_pages_sorted[i]);
+        }
+        free(heap_pages_sorted);
+        heap_allocated_pages = 0;
+        heap_pages_sorted_length = 0;
+        heap_pages_lomem = 0;
+        heap_pages_himem = 0;
 
         for (int i = 0; i < SIZE_POOL_COUNT; i++) {
             rb_size_pool_t *size_pool = &size_pools[i];
@@ -1844,15 +1938,15 @@ heap_pages_expand_sorted_to(rb_objspace_t *objspace, size_t next_length)
               next_length, size);
 
     if (heap_pages_sorted_length > 0) {
-	sorted = (struct heap_page **)realloc(heap_pages_sorted, size);
-	if (sorted) heap_pages_sorted = sorted;
+        sorted = (struct heap_page **)realloc(heap_pages_sorted, size);
+        if (sorted) heap_pages_sorted = sorted;
     }
     else {
-	sorted = heap_pages_sorted = (struct heap_page **)malloc(size);
+        sorted = heap_pages_sorted = (struct heap_page **)malloc(size);
     }
 
     if (sorted == 0) {
-	rb_memerror();
+        rb_memerror();
     }
 
     heap_pages_sorted_length = next_length;
@@ -1874,7 +1968,7 @@ heap_pages_expand_sorted(rb_objspace_t *objspace)
     }
 
     if (next_length > heap_pages_sorted_length) {
-	heap_pages_expand_sorted_to(objspace, next_length);
+        heap_pages_expand_sorted_to(objspace, next_length);
     }
 
     GC_ASSERT(heap_allocatable_pages(objspace) + heap_eden_total_pages(objspace) <= heap_pages_sorted_length);
@@ -1897,12 +1991,12 @@ heap_page_add_freeobj(rb_objspace_t *objspace, struct heap_page *page, VALUE obj
 
     asan_unpoison_object(obj, false);
 
-    asan_unpoison_memory_region(&page->freelist, sizeof(RVALUE*), false);
+    asan_unlock_freelist(page);
 
     p->as.free.flags = 0;
     p->as.free.next = page->freelist;
     page->freelist = p;
-    asan_poison_memory_region(&page->freelist, sizeof(RVALUE*));
+    asan_lock_freelist(page);
 
     if (RGENGC_CHECK_MODE &&
         /* obj should belong to page */
@@ -1919,7 +2013,7 @@ heap_page_add_freeobj(rb_objspace_t *objspace, struct heap_page *page, VALUE obj
 static inline void
 heap_add_freepage(rb_heap_t *heap, struct heap_page *page)
 {
-    asan_unpoison_memory_region(&page->freelist, sizeof(RVALUE*), false);
+    asan_unlock_freelist(page);
     GC_ASSERT(page->free_slots != 0);
     GC_ASSERT(page->freelist != NULL);
 
@@ -1928,14 +2022,14 @@ heap_add_freepage(rb_heap_t *heap, struct heap_page *page)
 
     RUBY_DEBUG_LOG("page:%p freelist:%p", (void *)page, (void *)page->freelist);
 
-    asan_poison_memory_region(&page->freelist, sizeof(RVALUE*));
+    asan_lock_freelist(page);
 }
 
 #if GC_ENABLE_INCREMENTAL_MARK
 static inline void
 heap_add_poolpage(rb_objspace_t *objspace, rb_heap_t *heap, struct heap_page *page)
 {
-    asan_unpoison_memory_region(&page->freelist, sizeof(RVALUE*), false);
+    asan_unlock_freelist(page);
     GC_ASSERT(page->free_slots != 0);
     GC_ASSERT(page->freelist != NULL);
 
@@ -1943,7 +2037,7 @@ heap_add_poolpage(rb_objspace_t *objspace, rb_heap_t *heap, struct heap_page *pa
     heap->pooled_pages = page;
     objspace->rincgc.pooled_slots += page->free_slots;
 
-    asan_poison_memory_region(&page->freelist, sizeof(RVALUE*));
+    asan_lock_freelist(page);
 }
 #endif
 
@@ -1962,19 +2056,17 @@ heap_page_body_free(struct heap_page_body *page_body)
 {
     GC_ASSERT((uintptr_t)page_body % HEAP_PAGE_ALIGN == 0);
 
-#ifdef HAVE_MMAP
     if (HEAP_PAGE_ALLOC_USE_MMAP) {
+#ifdef HAVE_MMAP
         GC_ASSERT(HEAP_PAGE_SIZE % sysconf(_SC_PAGE_SIZE) == 0);
         if (munmap(page_body, HEAP_PAGE_SIZE)) {
             rb_bug("heap_page_body_free: munmap failed");
         }
+#endif
     }
     else {
         rb_aligned_free(page_body, HEAP_PAGE_SIZE);
     }
-#else
-    rb_aligned_free(page_body, HEAP_PAGE_SIZE);
-#endif
 }
 
 static void
@@ -2020,7 +2112,7 @@ heap_pages_free_unused_pages(rb_objspace_t *objspace)
         GC_ASSERT(himem <= heap_pages_himem);
         heap_pages_himem = himem;
 
-	GC_ASSERT(j == heap_allocated_pages);
+        GC_ASSERT(j == heap_allocated_pages);
     }
 }
 
@@ -2029,8 +2121,8 @@ heap_page_body_allocate(void)
 {
     struct heap_page_body *page_body;
 
-#ifdef HAVE_MMAP
     if (HEAP_PAGE_ALLOC_USE_MMAP) {
+#ifdef HAVE_MMAP
         GC_ASSERT(HEAP_PAGE_ALIGN % sysconf(_SC_PAGE_SIZE) == 0);
 
         char *ptr = mmap(NULL, HEAP_PAGE_ALIGN + HEAP_PAGE_SIZE,
@@ -2061,13 +2153,11 @@ heap_page_body_allocate(void)
         }
 
         page_body = (struct heap_page_body *)aligned;
+#endif
     }
     else {
         page_body = rb_aligned_malloc(HEAP_PAGE_ALIGN, HEAP_PAGE_SIZE);
     }
-#else
-    page_body = rb_aligned_malloc(HEAP_PAGE_ALIGN, HEAP_PAGE_SIZE);
-#endif
 
     GC_ASSERT((uintptr_t)page_body % HEAP_PAGE_ALIGN == 0);
 
@@ -2086,20 +2176,20 @@ heap_page_allocate(rb_objspace_t *objspace, rb_size_pool_t *size_pool)
     /* assign heap_page body (contains heap_page_header and RVALUEs) */
     struct heap_page_body *page_body = heap_page_body_allocate();
     if (page_body == 0) {
-	rb_memerror();
+        rb_memerror();
     }
 
     /* assign heap_page entry */
     page = calloc1(sizeof(struct heap_page));
     if (page == 0) {
         heap_page_body_free(page_body);
-	rb_memerror();
+        rb_memerror();
     }
 
     /* adjust obj_limit (object number available in this page) */
     start = (uintptr_t)((VALUE)page_body + sizeof(struct heap_page_header));
 
-    if ((VALUE)start % BASE_SLOT_SIZE != 0) {
+    if (start % BASE_SLOT_SIZE != 0) {
         int delta = BASE_SLOT_SIZE - (start % BASE_SLOT_SIZE);
         start = start + delta;
         GC_ASSERT(NUM_IN_PAGE(start) == 0 || NUM_IN_PAGE(start) == 1);
@@ -2114,7 +2204,7 @@ heap_page_allocate(rb_objspace_t *objspace, rb_size_pool_t *size_pool)
 
         GC_ASSERT(NUM_IN_PAGE(start) * BASE_SLOT_SIZE % stride == 0);
 
-	limit = (HEAP_PAGE_SIZE - (int)(start - (uintptr_t)page_body))/(int)stride;
+        limit = (HEAP_PAGE_SIZE - (int)(start - (uintptr_t)page_body))/(int)stride;
     }
     end = start + (limit * (int)stride);
 
@@ -2122,23 +2212,23 @@ heap_page_allocate(rb_objspace_t *objspace, rb_size_pool_t *size_pool)
     lo = 0;
     hi = (uintptr_t)heap_allocated_pages;
     while (lo < hi) {
-	struct heap_page *mid_page;
+        struct heap_page *mid_page;
 
-	mid = (lo + hi) / 2;
-	mid_page = heap_pages_sorted[mid];
-	if ((uintptr_t)mid_page->start < start) {
-	    lo = mid + 1;
-	}
-	else if ((uintptr_t)mid_page->start > start) {
-	    hi = mid;
-	}
-	else {
-	    rb_bug("same heap page is allocated: %p at %"PRIuVALUE, (void *)page_body, (VALUE)mid);
-	}
+        mid = (lo + hi) / 2;
+        mid_page = heap_pages_sorted[mid];
+        if ((uintptr_t)mid_page->start < start) {
+            lo = mid + 1;
+        }
+        else if ((uintptr_t)mid_page->start > start) {
+            hi = mid;
+        }
+        else {
+            rb_bug("same heap page is allocated: %p at %"PRIuVALUE, (void *)page_body, (VALUE)mid);
+        }
     }
 
     if (hi < (uintptr_t)heap_allocated_pages) {
-	MEMMOVE(&heap_pages_sorted[hi+1], &heap_pages_sorted[hi], struct heap_page_header*, heap_allocated_pages - hi);
+        MEMMOVE(&heap_pages_sorted[hi+1], &heap_pages_sorted[hi], struct heap_page_header*, heap_allocated_pages - hi);
     }
 
     heap_pages_sorted[hi] = page;
@@ -2152,8 +2242,8 @@ heap_page_allocate(rb_objspace_t *objspace, rb_size_pool_t *size_pool)
     size_pool->total_allocated_pages++;
 
     if (heap_allocated_pages > heap_pages_sorted_length) {
-	rb_bug("heap_page_allocate: allocated(%"PRIdSIZE") > sorted(%"PRIdSIZE")",
-	       heap_allocated_pages, heap_pages_sorted_length);
+        rb_bug("heap_page_allocate: allocated(%"PRIdSIZE") > sorted(%"PRIdSIZE")",
+               heap_allocated_pages, heap_pages_sorted_length);
     }
 
     if (heap_pages_lomem == 0 || heap_pages_lomem > start) heap_pages_lomem = start;
@@ -2166,12 +2256,12 @@ heap_page_allocate(rb_objspace_t *objspace, rb_size_pool_t *size_pool)
     page_body->header.page = page;
 
     for (p = start; p != end; p += stride) {
-	gc_report(3, objspace, "assign_heap_page: %p is added to freelist\n", (void *)p);
-	heap_page_add_freeobj(objspace, page, (VALUE)p);
+        gc_report(3, objspace, "assign_heap_page: %p is added to freelist\n", (void *)p);
+        heap_page_add_freeobj(objspace, page, (VALUE)p);
     }
     page->free_slots = limit;
 
-    asan_poison_memory_region(&page->freelist, sizeof(RVALUE*));
+    asan_lock_freelist(page);
     return page;
 }
 
@@ -2181,12 +2271,12 @@ heap_page_resurrect(rb_objspace_t *objspace, rb_size_pool_t *size_pool)
     struct heap_page *page = 0, *next;
 
     ccan_list_for_each_safe(&SIZE_POOL_TOMB_HEAP(size_pool)->pages, page, next, page_node) {
-        asan_unpoison_memory_region(&page->freelist, sizeof(RVALUE*), false);
-	if (page->freelist != NULL) {
-	    heap_unlink_page(objspace, &size_pool->tomb_heap, page);
-            asan_poison_memory_region(&page->freelist, sizeof(RVALUE*));
-	    return page;
-	}
+        asan_unlock_freelist(page);
+        if (page->freelist != NULL) {
+            heap_unlink_page(objspace, &size_pool->tomb_heap, page);
+            asan_lock_freelist(page);
+            return page;
+        }
     }
 
     return NULL;
@@ -2203,8 +2293,8 @@ heap_page_create(rb_objspace_t *objspace, rb_size_pool_t *size_pool)
     page = heap_page_resurrect(objspace, size_pool);
 
     if (page == NULL) {
-	page = heap_page_allocate(objspace, size_pool);
-	method = "allocate";
+        page = heap_page_allocate(objspace, size_pool);
+        method = "allocate";
     }
     if (0) fprintf(stderr, "heap_page_create: %s - %p, "
                    "heap_allocated_pages: %"PRIdSIZE", "
@@ -2241,45 +2331,49 @@ heap_add_pages(rb_objspace_t *objspace, rb_size_pool_t *size_pool, rb_heap_t *he
     size_pool_allocatable_pages_set(objspace, size_pool, add);
 
     for (i = 0; i < add; i++) {
-	heap_assign_page(objspace, size_pool, heap);
+        heap_assign_page(objspace, size_pool, heap);
     }
 
     GC_ASSERT(size_pool->allocatable_pages == 0);
 }
 
 static size_t
-heap_extend_pages(rb_objspace_t *objspace, size_t free_slots, size_t total_slots, size_t used)
+heap_extend_pages(rb_objspace_t *objspace, rb_size_pool_t *size_pool, size_t free_slots, size_t total_slots, size_t used)
 {
     double goal_ratio = gc_params.heap_free_slots_goal_ratio;
     size_t next_used;
 
     if (goal_ratio == 0.0) {
-	next_used = (size_t)(used * gc_params.growth_factor);
+        next_used = (size_t)(used * gc_params.growth_factor);
+    }
+    else if (total_slots == 0) {
+        int multiple = size_pool->slot_size / BASE_SLOT_SIZE;
+        next_used = (gc_params.heap_init_slots * multiple) / HEAP_PAGE_OBJ_LIMIT;
     }
     else {
-	/* Find `f' where free_slots = f * total_slots * goal_ratio
-	 * => f = (total_slots - free_slots) / ((1 - goal_ratio) * total_slots)
-	 */
-	double f = (double)(total_slots - free_slots) / ((1 - goal_ratio) * total_slots);
+        /* Find `f' where free_slots = f * total_slots * goal_ratio
+         * => f = (total_slots - free_slots) / ((1 - goal_ratio) * total_slots)
+         */
+        double f = (double)(total_slots - free_slots) / ((1 - goal_ratio) * total_slots);
 
-	if (f > gc_params.growth_factor) f = gc_params.growth_factor;
-	if (f < 1.0) f = 1.1;
+        if (f > gc_params.growth_factor) f = gc_params.growth_factor;
+        if (f < 1.0) f = 1.1;
 
-	next_used = (size_t)(f * used);
+        next_used = (size_t)(f * used);
 
-	if (0) {
-	    fprintf(stderr,
-		    "free_slots(%8"PRIuSIZE")/total_slots(%8"PRIuSIZE")=%1.2f,"
-		    " G(%1.2f), f(%1.2f),"
-		    " used(%8"PRIuSIZE") => next_used(%8"PRIuSIZE")\n",
-		    free_slots, total_slots, free_slots/(double)total_slots,
-		    goal_ratio, f, used, next_used);
-	}
+        if (0) {
+            fprintf(stderr,
+                    "free_slots(%8"PRIuSIZE")/total_slots(%8"PRIuSIZE")=%1.2f,"
+                    " G(%1.2f), f(%1.2f),"
+                    " used(%8"PRIuSIZE") => next_used(%8"PRIuSIZE")\n",
+                    free_slots, total_slots, free_slots/(double)total_slots,
+                    goal_ratio, f, used, next_used);
+        }
     }
 
     if (gc_params.growth_max_slots > 0) {
-	size_t max_used = (size_t)(used + gc_params.growth_max_slots/HEAP_PAGE_OBJ_LIMIT);
-	if (next_used > max_used) next_used = max_used;
+        size_t max_used = (size_t)(used + gc_params.growth_max_slots/HEAP_PAGE_OBJ_LIMIT);
+        if (next_used > max_used) next_used = max_used;
     }
 
     size_t extend_page_count = next_used - used;
@@ -2293,37 +2387,80 @@ static int
 heap_increment(rb_objspace_t *objspace, rb_size_pool_t *size_pool, rb_heap_t *heap)
 {
     if (size_pool->allocatable_pages > 0) {
-	gc_report(1, objspace, "heap_increment: heap_pages_sorted_length: %"PRIdSIZE", "
+        gc_report(1, objspace, "heap_increment: heap_pages_sorted_length: %"PRIdSIZE", "
                   "heap_pages_inc: %"PRIdSIZE", heap->total_pages: %"PRIdSIZE"\n",
-		  heap_pages_sorted_length, size_pool->allocatable_pages, heap->total_pages);
+                  heap_pages_sorted_length, size_pool->allocatable_pages, heap->total_pages);
 
-	GC_ASSERT(heap_allocatable_pages(objspace) + heap_eden_total_pages(objspace) <= heap_pages_sorted_length);
-	GC_ASSERT(heap_allocated_pages <= heap_pages_sorted_length);
+        GC_ASSERT(heap_allocatable_pages(objspace) + heap_eden_total_pages(objspace) <= heap_pages_sorted_length);
+        GC_ASSERT(heap_allocated_pages <= heap_pages_sorted_length);
 
-	heap_assign_page(objspace, size_pool, heap);
-	return TRUE;
+        heap_assign_page(objspace, size_pool, heap);
+        return TRUE;
     }
     return FALSE;
 }
 
 static void
-heap_prepare(rb_objspace_t *objspace, rb_size_pool_t *size_pool, rb_heap_t *heap)
+gc_continue(rb_objspace_t *objspace, rb_size_pool_t *size_pool, rb_heap_t *heap)
 {
-    GC_ASSERT(heap->free_pages == NULL);
-
-    if (is_incremental_marking(objspace)) {
-	gc_marks_continue(objspace, size_pool, heap);
+    /* Continue marking if in incremental marking. */
+    if (heap->free_pages == NULL && is_incremental_marking(objspace)) {
+        gc_marks_continue(objspace, size_pool, heap);
     }
 
+    /* Continue sweeping if in lazy sweeping or the previous incremental
+     * marking finished and did not yield a free page. */
     if (heap->free_pages == NULL && is_lazy_sweeping(objspace)) {
         gc_sweep_continue(objspace, size_pool, heap);
     }
+}
+
+static void
+heap_prepare(rb_objspace_t *objspace, rb_size_pool_t *size_pool, rb_heap_t *heap)
+{
+    GC_ASSERT(heap->free_pages == NULL);
 
+    /* Continue incremental marking or lazy sweeping, if in any of those steps. */
+    gc_continue(objspace, size_pool, heap);
+
+    /* If we still don't have a free page and not allowed to create a new page,
+     * we should start a new GC cycle. */
     if (heap->free_pages == NULL &&
-        (will_be_incremental_marking(objspace) || heap_increment(objspace, size_pool, heap) == FALSE) &&
-	gc_start(objspace, GPR_FLAG_NEWOBJ) == FALSE) {
-	rb_memerror();
+            (will_be_incremental_marking(objspace) ||
+                (heap_increment(objspace, size_pool, heap) == FALSE))) {
+        if (gc_start(objspace, GPR_FLAG_NEWOBJ) == FALSE) {
+            rb_memerror();
+        }
+        else {
+            /* Do steps of incremental marking or lazy sweeping if the GC run permits. */
+            gc_continue(objspace, size_pool, heap);
+
+            /* If we're not incremental marking (e.g. a minor GC) or finished
+             * sweeping and still don't have a free page, then
+             * gc_sweep_finish_size_pool should allow us to create a new page. */
+            if (heap->free_pages == NULL && !heap_increment(objspace, size_pool, heap)) {
+                if (objspace->rgengc.need_major_gc == GPR_FLAG_NONE) {
+                    rb_bug("cannot create a new page after GC");
+                }
+                else { // Major GC is required, which will allow us to create new page
+                    if (gc_start(objspace, GPR_FLAG_NEWOBJ) == FALSE) {
+                        rb_memerror();
+                    }
+                    else {
+                        /* Do steps of incremental marking or lazy sweeping. */
+                        gc_continue(objspace, size_pool, heap);
+
+                        if (heap->free_pages == NULL &&
+                                !heap_increment(objspace, size_pool, heap)) {
+                            rb_bug("cannot create a new page after major GC");
+                        }
+                    }
+                }
+            }
+        }
     }
+
+    GC_ASSERT(heap->free_pages != NULL);
 }
 
 void
@@ -2337,6 +2474,7 @@ rb_objspace_set_event_hook(const rb_event_flag_t event)
 static void
 gc_event_hook_body(rb_execution_context_t *ec, rb_objspace_t *objspace, const rb_event_flag_t event, VALUE data)
 {
+    if (UNLIKELY(!ec->cfp)) return;
     const VALUE *pc = ec->cfp->pc;
     if (pc && VM_FRAME_RUBYFRAME_P(ec->cfp)) {
         /* increment PC because source line is calculated with PC-1 */
@@ -2352,7 +2490,7 @@ gc_event_hook_body(rb_execution_context_t *ec, rb_objspace_t *objspace, const rb
 #define gc_event_hook_prep(objspace, event, data, prep) do { \
     if (UNLIKELY(gc_event_hook_needed_p(objspace, event))) { \
         prep; \
-	gc_event_hook_body(GET_EC(), (objspace), (event), (data)); \
+        gc_event_hook_body(GET_EC(), (objspace), (event), (data)); \
     } \
 } while (0)
 
@@ -2451,7 +2589,7 @@ newobj_init(VALUE klass, VALUE flags, int wb_protected, rb_objspace_t *objspace,
 size_t
 rb_gc_obj_slot_size(VALUE obj)
 {
-    return GET_HEAP_PAGE(obj)->slot_size;
+    return GET_HEAP_PAGE(obj)->slot_size - RVALUE_OVERHEAD;
 }
 
 static inline size_t
@@ -2466,9 +2604,17 @@ size_pool_slot_size(unsigned char pool_id)
     GC_ASSERT(size_pools[pool_id].slot_size == (short)slot_size);
 #endif
 
+    slot_size -= RVALUE_OVERHEAD;
+
     return slot_size;
 }
 
+size_t
+rb_size_pool_slot_size(unsigned char pool_id)
+{
+    return size_pool_slot_size(pool_id);
+}
+
 bool
 rb_gc_size_allocatable_p(size_t size)
 {
@@ -2523,16 +2669,17 @@ heap_next_free_page(rb_objspace_t *objspace, rb_size_pool_t *size_pool, rb_heap_
 
     struct heap_page *page;
 
-    while (heap->free_pages == NULL) {
+    if (heap->free_pages == NULL) {
         heap_prepare(objspace, size_pool, heap);
     }
+
     page = heap->free_pages;
     heap->free_pages = page->free_next;
 
     GC_ASSERT(page->free_slots != 0);
     RUBY_DEBUG_LOG("page:%p freelist:%p cnt:%d", (void *)page, (void *)page->freelist, page->free_slots);
 
-    asan_unpoison_memory_region(&page->freelist, sizeof(RVALUE*), false);
+    asan_unlock_freelist(page);
 
     return page;
 }
@@ -2573,6 +2720,8 @@ static inline size_t
 size_pool_idx_for_size(size_t size)
 {
 #if USE_RVARGC
+    size += RVALUE_OVERHEAD;
+
     size_t slot_count = CEILDIV(size, BASE_SLOT_SIZE);
 
     /* size_pool_idx is ceil(log2(slot_count)) */
@@ -2647,6 +2796,12 @@ newobj_alloc(rb_objspace_t *objspace, rb_ractor_t *cr, size_t size_pool_idx, boo
     return obj;
 }
 
+static void
+newobj_zero_slot(VALUE obj)
+{
+    memset((char *)obj + sizeof(struct RBasic), 0, rb_gc_obj_slot_size(obj) - sizeof(struct RBasic));
+}
+
 ALWAYS_INLINE(static VALUE newobj_slowpath(VALUE klass, VALUE flags, rb_objspace_t *objspace, rb_ractor_t *cr, int wb_protected, size_t size_pool_idx));
 
 static inline VALUE
@@ -2672,9 +2827,12 @@ newobj_slowpath(VALUE klass, VALUE flags, rb_objspace_t *objspace, rb_ractor_t *
         }
 
         obj = newobj_alloc(objspace, cr, size_pool_idx, true);
+#if SHAPE_IN_BASIC_FLAGS
+        flags |= (VALUE)(size_pool_idx) << SHAPE_FLAG_SHIFT;
+#endif
         newobj_init(klass, flags, wb_protected, objspace, obj);
 
-        gc_event_hook_prep(objspace, RUBY_INTERNAL_EVENT_NEWOBJ, obj, newobj_fill(obj, 0, 0, 0));
+        gc_event_hook_prep(objspace, RUBY_INTERNAL_EVENT_NEWOBJ, obj, newobj_zero_slot(obj));
     }
     RB_VM_LOCK_LEAVE_CR_LEV(cr, &lev);
 
@@ -2723,6 +2881,9 @@ newobj_of0(VALUE klass, VALUE flags, int wb_protected, rb_ractor_t *cr, size_t a
                   gc_event_hook_available_p(objspace)) &&
             wb_protected) {
         obj = newobj_alloc(objspace, cr, size_pool_idx, false);
+#if SHAPE_IN_BASIC_FLAGS
+        flags |= (VALUE)size_pool_idx << SHAPE_FLAG_SHIFT;
+#endif
         newobj_init(klass, flags, wb_protected, objspace, obj);
     }
     else {
@@ -2776,30 +2937,66 @@ rb_ec_wb_protected_newobj_of(rb_execution_context_t *ec, VALUE klass, VALUE flag
 VALUE
 rb_newobj(void)
 {
-    return newobj_of(0, T_NONE, 0, 0, 0, FALSE, sizeof(RVALUE));
+    return newobj_of(0, T_NONE, 0, 0, 0, FALSE, RVALUE_SIZE);
+}
+
+static size_t
+rb_obj_embedded_size(uint32_t numiv)
+{
+    return offsetof(struct RObject, as.ary) + (sizeof(VALUE) * numiv);
+}
+
+static VALUE
+rb_class_instance_allocate_internal(VALUE klass, VALUE flags, bool wb_protected)
+{
+    GC_ASSERT((flags & RUBY_T_MASK) == T_OBJECT);
+    GC_ASSERT(flags & ROBJECT_EMBED);
+
+    size_t size;
+#if USE_RVARGC
+    uint32_t index_tbl_num_entries = RCLASS_EXT(klass)->max_iv_count;
+
+    size = rb_obj_embedded_size(index_tbl_num_entries);
+    if (!rb_gc_size_allocatable_p(size)) {
+        size = sizeof(struct RObject);
+    }
+#else
+    size = sizeof(struct RObject);
+#endif
+
+    VALUE obj = newobj_of(klass, flags, 0, 0, 0, wb_protected, size);
+    RUBY_ASSERT(rb_shape_get_shape(obj)->type == SHAPE_ROOT ||
+            rb_shape_get_shape(obj)->type == SHAPE_INITIAL_CAPACITY);
+
+    // Set the shape to the specific T_OBJECT shape which is always
+    // SIZE_POOL_COUNT away from the root shape.
+    ROBJECT_SET_SHAPE_ID(obj, ROBJECT_SHAPE_ID(obj) + SIZE_POOL_COUNT);
+
+#if RUBY_DEBUG
+    RUBY_ASSERT(!rb_shape_obj_too_complex(obj));
+    VALUE *ptr = ROBJECT_IVPTR(obj);
+    for (size_t i = 0; i < ROBJECT_IV_CAPACITY(obj); i++) {
+        ptr[i] = Qundef;
+    }
+#endif
+
+    return obj;
 }
 
 VALUE
 rb_newobj_of(VALUE klass, VALUE flags)
 {
     if ((flags & RUBY_T_MASK) == T_OBJECT) {
-        st_table *index_tbl = RCLASS_IV_INDEX_TBL(klass);
-
-        VALUE obj = newobj_of(klass, (flags | ROBJECT_EMBED) & ~FL_WB_PROTECTED , Qundef, Qundef, Qundef, flags & FL_WB_PROTECTED, sizeof(RVALUE));
-
-        if (index_tbl && index_tbl->num_entries > ROBJECT_EMBED_LEN_MAX) {
-            rb_init_iv_list(obj);
-        }
-        return obj;
+        return rb_class_instance_allocate_internal(klass, (flags | ROBJECT_EMBED) & ~FL_WB_PROTECTED, flags & FL_WB_PROTECTED);
     }
     else {
-        return newobj_of(klass, flags & ~FL_WB_PROTECTED, 0, 0, 0, flags & FL_WB_PROTECTED, sizeof(RVALUE));
+        return newobj_of(klass, flags & ~FL_WB_PROTECTED, 0, 0, 0, flags & FL_WB_PROTECTED, RVALUE_SIZE);
     }
 }
 
 #define UNEXPECTED_NODE(func) \
     rb_bug(#func"(): GC does not handle T_NODE 0x%x(%p) 0x%"PRIxVALUE, \
-	   BUILTIN_TYPE(obj), (void*)(obj), RBASIC(obj)->flags)
+           BUILTIN_TYPE(obj), (void*)(obj), RBASIC(obj)->flags)
 
 const char *
 rb_imemo_name(enum imemo_type type)
@@ -2831,7 +3028,7 @@ rb_imemo_name(enum imemo_type type)
 VALUE
 rb_imemo_new(enum imemo_type type, VALUE v1, VALUE v2, VALUE v3, VALUE v0)
 {
-    size_t size = sizeof(RVALUE);
+    size_t size = RVALUE_SIZE;
     VALUE flags = T_IMEMO | (type << FL_USHIFT);
     return newobj_of(v0, flags, v1, v2, v3, TRUE, size);
 }
@@ -2839,7 +3036,7 @@ rb_imemo_new(enum imemo_type type, VALUE v1, VALUE v2, VALUE v3, VALUE v0)
 static VALUE
 rb_imemo_tmpbuf_new(VALUE v1, VALUE v2, VALUE v3, VALUE v0)
 {
-    size_t size = sizeof(RVALUE);
+    size_t size = sizeof(struct rb_imemo_tmpbuf_struct);
     VALUE flags = T_IMEMO | (imemo_tmpbuf << FL_USHIFT);
     return newobj_of(v0, flags, v1, v2, v3, FALSE, size);
 }
@@ -2900,20 +3097,10 @@ rb_imemo_new_debug(enum imemo_type type, VALUE v1, VALUE v2, VALUE v3, VALUE v0,
 }
 #endif
 
-VALUE
+MJIT_FUNC_EXPORTED VALUE
 rb_class_allocate_instance(VALUE klass)
 {
-    st_table *index_tbl = RCLASS_IV_INDEX_TBL(klass);
-
-    VALUE flags = T_OBJECT | ROBJECT_EMBED;
-
-    VALUE obj = newobj_of(klass, flags, Qundef, Qundef, Qundef, RGENGC_WB_PROTECTED_OBJECT, sizeof(RVALUE));
-
-    if (index_tbl && index_tbl->num_entries > ROBJECT_EMBED_LEN_MAX) {
-        rb_init_iv_list(obj);
-    }
-
-    return obj;
+    return rb_class_instance_allocate_internal(klass, T_OBJECT | ROBJECT_EMBED, RGENGC_WB_PROTECTED_OBJECT);
 }
 
 static inline void
@@ -2930,7 +3117,7 @@ rb_data_object_wrap(VALUE klass, void *datap, RUBY_DATA_FUNC dmark, RUBY_DATA_FU
 {
     RUBY_ASSERT_ALWAYS(dfree != (RUBY_DATA_FUNC)1);
     if (klass) rb_data_object_check(klass);
-    return newobj_of(klass, T_DATA, (VALUE)dmark, (VALUE)dfree, (VALUE)datap, FALSE, sizeof(RVALUE));
+    return newobj_of(klass, T_DATA, (VALUE)dmark, (VALUE)dfree, (VALUE)datap, FALSE, sizeof(struct RTypedData));
 }
 
 VALUE
@@ -2946,7 +3133,7 @@ rb_data_typed_object_wrap(VALUE klass, void *datap, const rb_data_type_t *type)
 {
     RBIMPL_NONNULL_ARG(type);
     if (klass) rb_data_object_check(klass);
-    return newobj_of(klass, T_DATA, (VALUE)type, (VALUE)1, (VALUE)datap, type->flags & RUBY_FL_WB_PROTECTED, sizeof(RVALUE));
+    return newobj_of(klass, T_DATA, (VALUE)type, (VALUE)1, (VALUE)datap, type->flags & RUBY_FL_WB_PROTECTED, sizeof(struct RTypedData));
 }
 
 VALUE
@@ -2961,11 +3148,11 @@ size_t
 rb_objspace_data_type_memsize(VALUE obj)
 {
     if (RTYPEDDATA_P(obj)) {
-	const rb_data_type_t *type = RTYPEDDATA_TYPE(obj);
-	const void *ptr = RTYPEDDATA_DATA(obj);
-	if (ptr && type->function.dsize) {
-	    return type->function.dsize(ptr);
-	}
+        const rb_data_type_t *type = RTYPEDDATA_TYPE(obj);
+        const void *ptr = RTYPEDDATA_DATA(obj);
+        if (ptr && type->function.dsize) {
+            return type->function.dsize(ptr);
+        }
     }
     return 0;
 }
@@ -2974,10 +3161,10 @@ const char *
 rb_objspace_data_type_name(VALUE obj)
 {
     if (RTYPEDDATA_P(obj)) {
-	return RTYPEDDATA_TYPE(obj)->wrap_struct_name;
+        return RTYPEDDATA_TYPE(obj)->wrap_struct_name;
     }
     else {
-	return 0;
+        return 0;
     }
 }
 
@@ -3065,20 +3252,6 @@ rb_free_const_table(struct rb_id_table *tbl)
     rb_id_table_free(tbl);
 }
 
-static int
-free_iv_index_tbl_free_i(st_data_t key, st_data_t value, st_data_t data)
-{
-    xfree((void *)value);
-    return ST_CONTINUE;
-}
-
-static void
-iv_index_tbl_free(struct st_table *tbl)
-{
-    st_foreach(tbl, free_iv_index_tbl_free_i, 0);
-    st_free_table(tbl);
-}
-
 // alive: if false, target pointers can be freed already.
 //        To check it, we need objspace parameter.
 static void
@@ -3088,8 +3261,7 @@ vm_ccs_free(struct rb_class_cc_entries *ccs, int alive, rb_objspace_t *objspace,
         for (int i=0; i<ccs->len; i++) {
             const struct rb_callcache *cc = ccs->entries[i].cc;
             if (!alive) {
-                void *ptr = asan_poisoned_object_p((VALUE)cc);
-                asan_unpoison_object((VALUE)cc, false);
+                void *ptr = asan_unpoison_object_temporary((VALUE)cc);
                 // ccs can be free'ed.
                 if (is_pointer_to_heap(objspace, (void *)cc) &&
                     IMEMO_TYPE_P(cc, imemo_callcache) &&
@@ -3260,15 +3432,15 @@ obj_free(rb_objspace_t *objspace, VALUE obj)
       case T_FIXNUM:
       case T_TRUE:
       case T_FALSE:
-	rb_bug("obj_free() called for broken object");
-	break;
+        rb_bug("obj_free() called for broken object");
+        break;
       default:
         break;
     }
 
     if (FL_TEST(obj, FL_EXIVAR)) {
-	rb_free_generic_ivar((VALUE)obj);
-	FL_UNSET(obj, FL_EXIVAR);
+        rb_free_generic_ivar((VALUE)obj);
+        FL_UNSET(obj, FL_EXIVAR);
     }
 
     if (FL_TEST(obj, FL_SEEN_OBJ_ID) && !FL_TEST(obj, FL_FINALIZE)) {
@@ -3279,16 +3451,20 @@ obj_free(rb_objspace_t *objspace, VALUE obj)
 
 #if RGENGC_CHECK_MODE
 #define CHECK(x) if (x(obj) != FALSE) rb_bug("obj_free: " #x "(%s) != FALSE", obj_info(obj))
-	CHECK(RVALUE_WB_UNPROTECTED);
-	CHECK(RVALUE_MARKED);
-	CHECK(RVALUE_MARKING);
-	CHECK(RVALUE_UNCOLLECTIBLE);
+        CHECK(RVALUE_WB_UNPROTECTED);
+        CHECK(RVALUE_MARKED);
+        CHECK(RVALUE_MARKING);
+        CHECK(RVALUE_UNCOLLECTIBLE);
 #undef CHECK
 #endif
 
     switch (BUILTIN_TYPE(obj)) {
       case T_OBJECT:
-        if (RANY(obj)->as.basic.flags & ROBJECT_EMBED) {
+        if (rb_shape_obj_too_complex(obj)) {
+            RB_DEBUG_COUNTER_INC(obj_obj_too_complex);
+            st_free_table(ROBJECT_IV_HASH(obj));
+        }
+        else if (RANY(obj)->as.basic.flags & ROBJECT_EMBED) {
             RB_DEBUG_COUNTER_INC(obj_obj_embed);
         }
         else if (ROBJ_TRANSIENT_P(obj)) {
@@ -3301,45 +3477,39 @@ obj_free(rb_objspace_t *objspace, VALUE obj)
         break;
       case T_MODULE:
       case T_CLASS:
-	rb_id_table_free(RCLASS_M_TBL(obj));
+        rb_id_table_free(RCLASS_M_TBL(obj));
         cc_table_free(objspace, obj, FALSE);
-	if (RCLASS_IV_TBL(obj)) {
-	    st_free_table(RCLASS_IV_TBL(obj));
-	}
-	if (RCLASS_CONST_TBL(obj)) {
-	    rb_free_const_table(RCLASS_CONST_TBL(obj));
-	}
-	if (RCLASS_IV_INDEX_TBL(obj)) {
-            iv_index_tbl_free(RCLASS_IV_INDEX_TBL(obj));
-	}
-	if (RCLASS_CVC_TBL(obj)) {
+        if (RCLASS_IVPTR(obj)) {
+            xfree(RCLASS_IVPTR(obj));
+        }
+        if (RCLASS_CONST_TBL(obj)) {
+            rb_free_const_table(RCLASS_CONST_TBL(obj));
+        }
+        if (RCLASS_CVC_TBL(obj)) {
             rb_id_table_foreach_values(RCLASS_CVC_TBL(obj), cvar_table_free_i, NULL);
             rb_id_table_free(RCLASS_CVC_TBL(obj));
-	}
+        }
         rb_class_remove_subclass_head(obj);
-	rb_class_remove_from_module_subclasses(obj);
-	rb_class_remove_from_super_subclasses(obj);
+        rb_class_remove_from_module_subclasses(obj);
+        rb_class_remove_from_super_subclasses(obj);
         if (FL_TEST_RAW(obj, RCLASS_SUPERCLASSES_INCLUDE_SELF)) {
             xfree(RCLASS_SUPERCLASSES(obj));
         }
-#if SIZEOF_SERIAL_T != SIZEOF_VALUE && USE_RVARGC
-        xfree(RCLASS(obj)->class_serial_ptr);
-#endif
 
-#if !USE_RVARGC
-	if (RCLASS_EXT(obj))
+#if SIZE_POOL_COUNT == 1
+        if (RCLASS_EXT(obj))
             xfree(RCLASS_EXT(obj));
 #endif
 
         (void)RB_DEBUG_COUNTER_INC_IF(obj_module_ptr, BUILTIN_TYPE(obj) == T_MODULE);
         (void)RB_DEBUG_COUNTER_INC_IF(obj_class_ptr, BUILTIN_TYPE(obj) == T_CLASS);
-	break;
+        break;
       case T_STRING:
-	rb_str_free(obj);
-	break;
+        rb_str_free(obj);
+        break;
       case T_ARRAY:
         rb_ary_free(obj);
-	break;
+        break;
       case T_HASH:
 #if USE_DEBUG_COUNTER
         switch (RHASH_SIZE(obj)) {
@@ -3397,53 +3567,53 @@ obj_free(rb_objspace_t *objspace, VALUE obj)
             GC_ASSERT(RHASH_ST_TABLE_P(obj));
             st_free_table(RHASH(obj)->as.st);
         }
-	break;
+        break;
       case T_REGEXP:
-	if (RANY(obj)->as.regexp.ptr) {
-	    onig_free(RANY(obj)->as.regexp.ptr);
+        if (RANY(obj)->as.regexp.ptr) {
+            onig_free(RANY(obj)->as.regexp.ptr);
             RB_DEBUG_COUNTER_INC(obj_regexp_ptr);
-	}
-	break;
+        }
+        break;
       case T_DATA:
-	if (DATA_PTR(obj)) {
-	    int free_immediately = FALSE;
-	    void (*dfree)(void *);
-	    void *data = DATA_PTR(obj);
-
-	    if (RTYPEDDATA_P(obj)) {
-		free_immediately = (RANY(obj)->as.typeddata.type->flags & RUBY_TYPED_FREE_IMMEDIATELY) != 0;
-		dfree = RANY(obj)->as.typeddata.type->function.dfree;
-		if (0 && free_immediately == 0) {
-		    /* to expose non-free-immediate T_DATA */
-		    fprintf(stderr, "not immediate -> %s\n", RANY(obj)->as.typeddata.type->wrap_struct_name);
-		}
-	    }
-	    else {
-		dfree = RANY(obj)->as.data.dfree;
-	    }
-
-	    if (dfree) {
-		if (dfree == RUBY_DEFAULT_FREE) {
-		    xfree(data);
+        if (DATA_PTR(obj)) {
+            int free_immediately = FALSE;
+            void (*dfree)(void *);
+            void *data = DATA_PTR(obj);
+
+            if (RTYPEDDATA_P(obj)) {
+                free_immediately = (RANY(obj)->as.typeddata.type->flags & RUBY_TYPED_FREE_IMMEDIATELY) != 0;
+                dfree = RANY(obj)->as.typeddata.type->function.dfree;
+                if (0 && free_immediately == 0) {
+                    /* to expose non-free-immediate T_DATA */
+                    fprintf(stderr, "not immediate -> %s\n", RANY(obj)->as.typeddata.type->wrap_struct_name);
+                }
+            }
+            else {
+                dfree = RANY(obj)->as.data.dfree;
+            }
+
+            if (dfree) {
+                if (dfree == RUBY_DEFAULT_FREE) {
+                    xfree(data);
                     RB_DEBUG_COUNTER_INC(obj_data_xfree);
-		}
-		else if (free_immediately) {
-		    (*dfree)(data);
+                }
+                else if (free_immediately) {
+                    (*dfree)(data);
                     RB_DEBUG_COUNTER_INC(obj_data_imm_free);
-		}
-		else {
-		    make_zombie(objspace, obj, dfree, data);
+                }
+                else {
+                    make_zombie(objspace, obj, dfree, data);
                     RB_DEBUG_COUNTER_INC(obj_data_zombie);
-		    return FALSE;
-		}
-	    }
+                    return FALSE;
+                }
+            }
             else {
                 RB_DEBUG_COUNTER_INC(obj_data_empty);
             }
-	}
-	break;
+        }
+        break;
       case T_MATCH:
-	if (RANY(obj)->as.match.rmatch) {
+        if (RANY(obj)->as.match.rmatch) {
             struct rmatch *rm = RANY(obj)->as.match.rmatch;
 #if USE_DEBUG_COUNTER
             if (rm->regs.num_regs >= 8) {
@@ -3456,21 +3626,21 @@ obj_free(rb_objspace_t *objspace, VALUE obj)
                 RB_DEBUG_COUNTER_INC(obj_match_under4);
             }
 #endif
-	    onig_region_free(&rm->regs, 0);
+            onig_region_free(&rm->regs, 0);
             if (rm->char_offset)
-		xfree(rm->char_offset);
-	    xfree(rm);
+                xfree(rm->char_offset);
+            xfree(rm);
 
             RB_DEBUG_COUNTER_INC(obj_match_ptr);
-	}
-	break;
+        }
+        break;
       case T_FILE:
-	if (RANY(obj)->as.file.fptr) {
-	    make_io_zombie(objspace, obj);
+        if (RANY(obj)->as.file.fptr) {
+            make_io_zombie(objspace, obj);
             RB_DEBUG_COUNTER_INC(obj_file_ptr);
-	    return FALSE;
-	}
-	break;
+            return FALSE;
+        }
+        break;
       case T_RATIONAL:
         RB_DEBUG_COUNTER_INC(obj_rational);
         break;
@@ -3478,44 +3648,44 @@ obj_free(rb_objspace_t *objspace, VALUE obj)
         RB_DEBUG_COUNTER_INC(obj_complex);
         break;
       case T_MOVED:
-	break;
+        break;
       case T_ICLASS:
-	/* Basically , T_ICLASS shares table with the module */
+        /* Basically , T_ICLASS shares table with the module */
         if (RICLASS_OWNS_M_TBL_P(obj)) {
             /* Method table is not shared for origin iclasses of classes */
             rb_id_table_free(RCLASS_M_TBL(obj));
         }
-	if (RCLASS_CALLABLE_M_TBL(obj) != NULL) {
-	    rb_id_table_free(RCLASS_CALLABLE_M_TBL(obj));
-	}
+        if (RCLASS_CALLABLE_M_TBL(obj) != NULL) {
+            rb_id_table_free(RCLASS_CALLABLE_M_TBL(obj));
+        }
         rb_class_remove_subclass_head(obj);
         cc_table_free(objspace, obj, FALSE);
-	rb_class_remove_from_module_subclasses(obj);
-	rb_class_remove_from_super_subclasses(obj);
-#if !USE_RVARGC
+        rb_class_remove_from_module_subclasses(obj);
+        rb_class_remove_from_super_subclasses(obj);
+#if !RCLASS_EXT_EMBEDDED
         xfree(RCLASS_EXT(obj));
 #endif
 
         RB_DEBUG_COUNTER_INC(obj_iclass_ptr);
-	break;
+        break;
 
       case T_FLOAT:
         RB_DEBUG_COUNTER_INC(obj_float);
-	break;
+        break;
 
       case T_BIGNUM:
-	if (!BIGNUM_EMBED_P(obj) && BIGNUM_DIGITS(obj)) {
-	    xfree(BIGNUM_DIGITS(obj));
+        if (!BIGNUM_EMBED_P(obj) && BIGNUM_DIGITS(obj)) {
+            xfree(BIGNUM_DIGITS(obj));
             RB_DEBUG_COUNTER_INC(obj_bignum_ptr);
-	}
+        }
         else {
             RB_DEBUG_COUNTER_INC(obj_bignum_embed);
         }
-	break;
+        break;
 
       case T_NODE:
-	UNEXPECTED_NODE(obj_free);
-	break;
+        UNEXPECTED_NODE(obj_free);
+        break;
 
       case T_STRUCT:
         if ((RBASIC(obj)->flags & RSTRUCT_EMBED_LEN_MASK) ||
@@ -3528,39 +3698,39 @@ obj_free(rb_objspace_t *objspace, VALUE obj)
         else {
             xfree((void *)RANY(obj)->as.rstruct.as.heap.ptr);
             RB_DEBUG_COUNTER_INC(obj_struct_ptr);
-	}
-	break;
+        }
+        break;
 
       case T_SYMBOL:
-	{
+        {
             rb_gc_free_dsymbol(obj);
             RB_DEBUG_COUNTER_INC(obj_symbol);
-	}
-	break;
+        }
+        break;
 
       case T_IMEMO:
-	switch (imemo_type(obj)) {
-	  case imemo_ment:
-	    rb_free_method_entry(&RANY(obj)->as.imemo.ment);
+        switch (imemo_type(obj)) {
+          case imemo_ment:
+            rb_free_method_entry(&RANY(obj)->as.imemo.ment);
             RB_DEBUG_COUNTER_INC(obj_imemo_ment);
-	    break;
-	  case imemo_iseq:
-	    rb_iseq_free(&RANY(obj)->as.imemo.iseq);
+            break;
+          case imemo_iseq:
+            rb_iseq_free(&RANY(obj)->as.imemo.iseq);
             RB_DEBUG_COUNTER_INC(obj_imemo_iseq);
-	    break;
-	  case imemo_env:
-	    GC_ASSERT(VM_ENV_ESCAPED_P(RANY(obj)->as.imemo.env.ep));
-	    xfree((VALUE *)RANY(obj)->as.imemo.env.env);
+            break;
+          case imemo_env:
+            GC_ASSERT(VM_ENV_ESCAPED_P(RANY(obj)->as.imemo.env.ep));
+            xfree((VALUE *)RANY(obj)->as.imemo.env.env);
             RB_DEBUG_COUNTER_INC(obj_imemo_env);
-	    break;
-	  case imemo_tmpbuf:
-	    xfree(RANY(obj)->as.imemo.alloc.ptr);
+            break;
+          case imemo_tmpbuf:
+            xfree(RANY(obj)->as.imemo.alloc.ptr);
             RB_DEBUG_COUNTER_INC(obj_imemo_tmpbuf);
-	    break;
-	  case imemo_ast:
-	    rb_ast_free(&RANY(obj)->as.imemo.ast);
+            break;
+          case imemo_ast:
+            rb_ast_free(&RANY(obj)->as.imemo.ast);
             RB_DEBUG_COUNTER_INC(obj_imemo_ast);
-	    break;
+            break;
           case imemo_cref:
             RB_DEBUG_COUNTER_INC(obj_imemo_cref);
             break;
@@ -3588,20 +3758,20 @@ obj_free(rb_objspace_t *objspace, VALUE obj)
           case imemo_constcache:
             RB_DEBUG_COUNTER_INC(obj_imemo_constcache);
             break;
-	}
-	return TRUE;
+        }
+        return TRUE;
 
       default:
-	rb_bug("gc_sweep(): unknown data type 0x%x(%p) 0x%"PRIxVALUE,
-	       BUILTIN_TYPE(obj), (void*)obj, RBASIC(obj)->flags);
+        rb_bug("gc_sweep(): unknown data type 0x%x(%p) 0x%"PRIxVALUE,
+               BUILTIN_TYPE(obj), (void*)obj, RBASIC(obj)->flags);
     }
 
     if (FL_TEST(obj, FL_FINALIZE)) {
         make_zombie(objspace, obj, 0, 0);
-	return FALSE;
+        return FALSE;
     }
     else {
-	return TRUE;
+        return TRUE;
     }
 }
 
@@ -3640,18 +3810,9 @@ Init_heap(void)
 {
     rb_objspace_t *objspace = &rb_objspace;
 
-#if defined(HAVE_MMAP) && !defined(__wasm__) && !HAVE_CONST_PAGE_SIZE && !defined(PAGE_MAX_SIZE)
+#if defined(INIT_HEAP_PAGE_ALLOC_USE_MMAP)
     /* Need to determine if we can use mmap at runtime. */
-# ifdef PAGE_SIZE
-    /* If the PAGE_SIZE macro can be used. */
-    heap_page_alloc_use_mmap = PAGE_SIZE <= HEAP_PAGE_SIZE;
-# elif defined(HAVE_SYSCONF) && defined(_SC_PAGE_SIZE)
-    /* If we can use sysconf to determine the page size. */
-    heap_page_alloc_use_mmap = sysconf(_SC_PAGE_SIZE) <= HEAP_PAGE_SIZE;
-# else
-    /* Otherwise we can't determine the system page size, so don't use mmap. */
-    heap_page_alloc_use_mmap = FALSE;
-# endif
+    heap_page_alloc_use_mmap = INIT_HEAP_PAGE_ALLOC_USE_MMAP;
 #endif
 
     objspace->next_object_id = INT2FIX(OBJ_ID_INITIAL);
@@ -3773,7 +3934,8 @@ objspace_each_objects_try(VALUE arg)
             uintptr_t pstart = (uintptr_t)page->start;
             uintptr_t pend = pstart + (page->total_slots * size_pool->slot_size);
 
-            if ((*data->callback)((void *)pstart, (void *)pend, size_pool->slot_size, data->data)) {
+            if (!__asan_region_is_poisoned((void *)pstart, pend - pstart) &&
+                (*data->callback)((void *)pstart, (void *)pend, size_pool->slot_size, data->data)) {
                 break;
             }
 
@@ -3867,31 +4029,30 @@ static int
 internal_object_p(VALUE obj)
 {
     RVALUE *p = (RVALUE *)obj;
-    void *ptr = __asan_region_is_poisoned(p, SIZEOF_VALUE);
-    asan_unpoison_object(obj, false);
+    void *ptr = asan_unpoison_object_temporary(obj);
     bool used_p = p->as.basic.flags;
 
     if (used_p) {
         switch (BUILTIN_TYPE(obj)) {
-	  case T_NODE:
-	    UNEXPECTED_NODE(internal_object_p);
-	    break;
-	  case T_NONE:
+          case T_NODE:
+            UNEXPECTED_NODE(internal_object_p);
+            break;
+          case T_NONE:
           case T_MOVED:
-	  case T_IMEMO:
-	  case T_ICLASS:
-	  case T_ZOMBIE:
-	    break;
-	  case T_CLASS:
-	    if (!p->as.basic.klass) break;
-	    if (FL_TEST(obj, FL_SINGLETON)) {
-		return rb_singleton_class_internal_p(obj);
-	    }
-	    return 0;
-	  default:
-	    if (!p->as.basic.klass) break;
-	    return 0;
-	}
+          case T_IMEMO:
+          case T_ICLASS:
+          case T_ZOMBIE:
+            break;
+          case T_CLASS:
+            if (!p->as.basic.klass) break;
+            if (FL_TEST(obj, FL_SINGLETON)) {
+                return rb_singleton_class_internal_p(obj);
+            }
+            return 0;
+          default:
+            if (!p->as.basic.klass) break;
+            return 0;
+        }
     }
     if (ptr || ! used_p) {
         asan_poison_object(obj);
@@ -3912,14 +4073,14 @@ os_obj_of_i(void *vstart, void *vend, size_t stride, void *data)
 
     VALUE v = (VALUE)vstart;
     for (; v != (VALUE)vend; v += stride) {
-	if (!internal_object_p(v)) {
-	    if (!oes->of || rb_obj_is_kind_of(v, oes->of)) {
+        if (!internal_object_p(v)) {
+            if (!oes->of || rb_obj_is_kind_of(v, oes->of)) {
                 if (!rb_multi_ractor_p() || rb_ractor_shareable_p(v)) {
                     rb_yield(v);
                     oes->num++;
                 }
-	    }
-	}
+            }
+        }
     }
 
     return 0;
@@ -4011,8 +4172,8 @@ static void
 should_be_callable(VALUE block)
 {
     if (!rb_obj_respond_to(block, idCall, TRUE)) {
-	rb_raise(rb_eArgError, "wrong type argument %"PRIsVALUE" (should be callable)",
-		 rb_obj_class(block));
+        rb_raise(rb_eArgError, "wrong type argument %"PRIsVALUE" (should be callable)",
+                 rb_obj_class(block));
     }
 }
 
@@ -4020,8 +4181,8 @@ static void
 should_be_finalizable(VALUE obj)
 {
     if (!FL_ABLE(obj)) {
-	rb_raise(rb_eArgError, "cannot define finalizer for %s",
-		 rb_obj_classname(obj));
+        rb_raise(rb_eArgError, "cannot define finalizer for %s",
+                 rb_obj_classname(obj));
     }
     rb_check_frozen(obj);
 }
@@ -4096,10 +4257,10 @@ define_final(int argc, VALUE *argv, VALUE os)
     rb_scan_args(argc, argv, "11", &obj, &block);
     should_be_finalizable(obj);
     if (argc == 1) {
-	block = rb_block_proc();
+        block = rb_block_proc();
     }
     else {
-	should_be_callable(block);
+        should_be_callable(block);
     }
 
     if (rb_callable_receiver(block) == obj) {
@@ -4119,28 +4280,28 @@ define_final0(VALUE obj, VALUE block)
     RBASIC(obj)->flags |= FL_FINALIZE;
 
     if (st_lookup(finalizer_table, obj, &data)) {
-	table = (VALUE)data;
+        table = (VALUE)data;
 
-	/* avoid duplicate block, table is usually small */
-	{
-	    long len = RARRAY_LEN(table);
-	    long i;
+        /* avoid duplicate block, table is usually small */
+        {
+            long len = RARRAY_LEN(table);
+            long i;
 
             for (i = 0; i < len; i++) {
                 VALUE recv = RARRAY_AREF(table, i);
                 if (rb_equal(recv, block)) {
                     block = recv;
                     goto end;
-		}
-	    }
-	}
+                }
+            }
+        }
 
-	rb_ary_push(table, block);
+        rb_ary_push(table, block);
     }
     else {
-	table = rb_ary_new3(1, block);
-	RBASIC_CLEAR_CLASS(table);
-	st_add_direct(finalizer_table, obj, table);
+        table = rb_ary_new3(1, block);
+        RBASIC_CLEAR_CLASS(table);
+        st_add_direct(finalizer_table, obj, table);
     }
   end:
     block = rb_ary_new3(2, INT2FIX(0), block);
@@ -4165,8 +4326,8 @@ rb_gc_copy_finalizer(VALUE dest, VALUE obj)
 
     if (!FL_TEST(obj, FL_FINALIZE)) return;
     if (st_lookup(finalizer_table, obj, &data)) {
-	table = (VALUE)data;
-	st_insert(finalizer_table, dest, table);
+        table = (VALUE)data;
+        st_insert(finalizer_table, dest, table);
     }
     FL_SET(dest, FL_FINALIZE);
 }
@@ -4180,10 +4341,10 @@ run_single_final(VALUE cmd, VALUE objid)
 static void
 warn_exception_in_finalizer(rb_execution_context_t *ec, VALUE final)
 {
-    if (final != Qundef && !NIL_P(ruby_verbose)) {
-	VALUE errinfo = ec->errinfo;
-	rb_warn("Exception in finalizer %+"PRIsVALUE, final);
-	rb_ec_error_print(ec, errinfo);
+    if (!UNDEF_P(final) && !NIL_P(ruby_verbose)) {
+        VALUE errinfo = ec->errinfo;
+        rb_warn("Exception in finalizer %+"PRIsVALUE, final);
+        rb_ec_error_print(ec, errinfo);
     }
 }
 
@@ -4193,33 +4354,37 @@ run_finalizer(rb_objspace_t *objspace, VALUE obj, VALUE table)
     long i;
     enum ruby_tag_type state;
     volatile struct {
-	VALUE errinfo;
-	VALUE objid;
-	VALUE final;
-	rb_control_frame_t *cfp;
-	long finished;
+        VALUE errinfo;
+        VALUE objid;
+        VALUE final;
+        rb_control_frame_t *cfp;
+        VALUE *sp;
+        long finished;
     } saved;
+
     rb_execution_context_t * volatile ec = GET_EC();
 #define RESTORE_FINALIZER() (\
-	ec->cfp = saved.cfp, \
-	ec->errinfo = saved.errinfo)
+        ec->cfp = saved.cfp, \
+        ec->cfp->sp = saved.sp, \
+        ec->errinfo = saved.errinfo)
 
     saved.errinfo = ec->errinfo;
     saved.objid = rb_obj_id(obj);
     saved.cfp = ec->cfp;
+    saved.sp = ec->cfp->sp;
     saved.finished = 0;
     saved.final = Qundef;
 
     EC_PUSH_TAG(ec);
     state = EC_EXEC_TAG();
     if (state != TAG_NONE) {
-	++saved.finished;	/* skip failed finalizer */
-	warn_exception_in_finalizer(ec, ATOMIC_VALUE_EXCHANGE(saved.final, Qundef));
+        ++saved.finished;	/* skip failed finalizer */
+        warn_exception_in_finalizer(ec, ATOMIC_VALUE_EXCHANGE(saved.final, Qundef));
     }
     for (i = saved.finished;
-	 RESTORE_FINALIZER(), i<RARRAY_LEN(table);
-	 saved.finished = ++i) {
-	run_single_final(saved.final = RARRAY_AREF(table, i), saved.objid);
+         RESTORE_FINALIZER(), i<RARRAY_LEN(table);
+         saved.finished = ++i) {
+        run_single_final(saved.final = RARRAY_AREF(table, i), saved.objid);
     }
     EC_POP_TAG();
 #undef RESTORE_FINALIZER
@@ -4231,12 +4396,12 @@ run_final(rb_objspace_t *objspace, VALUE zombie)
     st_data_t key, table;
 
     if (RZOMBIE(zombie)->dfree) {
-	RZOMBIE(zombie)->dfree(RZOMBIE(zombie)->data);
+        RZOMBIE(zombie)->dfree(RZOMBIE(zombie)->data);
     }
 
     key = (st_data_t)zombie;
     if (st_delete(finalizer_table, &key, &table)) {
-	run_finalizer(objspace, zombie, (VALUE)table);
+        run_finalizer(objspace, zombie, (VALUE)table);
     }
 }
 
@@ -4250,7 +4415,7 @@ finalize_list(rb_objspace_t *objspace, VALUE zombie)
         next_zombie = RZOMBIE(zombie)->next;
         page = GET_HEAP_PAGE(zombie);
 
-	run_final(objspace, zombie);
+        run_final(objspace, zombie);
 
         RB_VM_LOCK_ENTER();
         {
@@ -4279,7 +4444,7 @@ finalize_deferred_heap_pages(rb_objspace_t *objspace)
 {
     VALUE zombie;
     while ((zombie = ATOMIC_VALUE_EXCHANGE(heap_pages_deferred_final, 0)) != 0) {
-	finalize_list(objspace, zombie);
+        finalize_list(objspace, zombie);
     }
 }
 
@@ -4306,7 +4471,7 @@ static void
 gc_finalize_deferred_register(rb_objspace_t *objspace)
 {
     if (rb_postponed_job_register_one(0, gc_finalize_deferred, objspace) == 0) {
-	rb_bug("gc_finalize_deferred_register: can't register finalizer.");
+        rb_bug("gc_finalize_deferred_register: can't register finalizer.");
     }
 }
 
@@ -4352,16 +4517,16 @@ rb_objspace_call_finalizer(rb_objspace_t *objspace)
 
     /* force to run finalizer */
     while (finalizer_table->num_entries) {
-	struct force_finalize_list *list = 0;
-	st_foreach(finalizer_table, force_chain_object, (st_data_t)&list);
-	while (list) {
-	    struct force_finalize_list *curr = list;
-	    st_data_t obj = (st_data_t)curr->obj;
-	    run_finalizer(objspace, curr->obj, curr->table);
-	    st_delete(finalizer_table, &obj, 0);
-	    list = curr->next;
-	    xfree(curr);
-	}
+        struct force_finalize_list *list = 0;
+        st_foreach(finalizer_table, force_chain_object, (st_data_t)&list);
+        while (list) {
+            struct force_finalize_list *curr = list;
+            st_data_t obj = (st_data_t)curr->obj;
+            run_finalizer(objspace, curr->obj, curr->table);
+            st_delete(finalizer_table, &obj, 0);
+            list = curr->next;
+            xfree(curr);
+        }
     }
 
     /* prohibit GC because force T_DATA finalizers can break an object graph consistency */
@@ -4380,39 +4545,38 @@ rb_objspace_call_finalizer(rb_objspace_t *objspace)
         uintptr_t pend = p + page->total_slots * stride;
         for (; p < pend; p += stride) {
             VALUE vp = (VALUE)p;
-            void *poisoned = asan_poisoned_object_p(vp);
-            asan_unpoison_object(vp, false);
+            void *poisoned = asan_unpoison_object_temporary(vp);
             switch (BUILTIN_TYPE(vp)) {
-	      case T_DATA:
-		if (!DATA_PTR(p) || !RANY(p)->as.data.dfree) break;
+              case T_DATA:
+                if (!DATA_PTR(p) || !RANY(p)->as.data.dfree) break;
                 if (rb_obj_is_thread(vp)) break;
                 if (rb_obj_is_mutex(vp)) break;
                 if (rb_obj_is_fiber(vp)) break;
                 if (rb_obj_is_main_ractor(vp)) break;
                 if (RTYPEDDATA_P(vp)) {
-		    RDATA(p)->dfree = RANY(p)->as.typeddata.type->function.dfree;
-		}
+                    RDATA(p)->dfree = RANY(p)->as.typeddata.type->function.dfree;
+                }
                 RANY(p)->as.free.flags = 0;
-		if (RANY(p)->as.data.dfree == RUBY_DEFAULT_FREE) {
-		    xfree(DATA_PTR(p));
-		}
-		else if (RANY(p)->as.data.dfree) {
+                if (RANY(p)->as.data.dfree == RUBY_DEFAULT_FREE) {
+                    xfree(DATA_PTR(p));
+                }
+                else if (RANY(p)->as.data.dfree) {
                     make_zombie(objspace, vp, RANY(p)->as.data.dfree, RANY(p)->as.data.data);
-		}
-		break;
-	      case T_FILE:
-		if (RANY(p)->as.file.fptr) {
+                }
+                break;
+              case T_FILE:
+                if (RANY(p)->as.file.fptr) {
                     make_io_zombie(objspace, vp);
-		}
-		break;
+                }
+                break;
               default:
                 break;
-	    }
+            }
             if (poisoned) {
                 GC_ASSERT(BUILTIN_TYPE(vp) == T_NONE);
                 asan_poison_object(vp);
             }
-	}
+        }
     }
 
     gc_exit(objspace, gc_enter_event_finalizer, &lock_lev);
@@ -4436,13 +4600,13 @@ static inline int
 is_garbage_object(rb_objspace_t *objspace, VALUE ptr)
 {
     if (!is_lazy_sweeping(objspace) ||
-	is_swept_object(objspace, ptr) ||
-	MARKED_IN_BITMAP(GET_HEAP_MARK_BITS(ptr), ptr)) {
+        is_swept_object(objspace, ptr) ||
+        MARKED_IN_BITMAP(GET_HEAP_MARK_BITS(ptr), ptr)) {
 
-	return FALSE;
+        return FALSE;
     }
     else {
-	return TRUE;
+        return TRUE;
     }
 }
 
@@ -4453,16 +4617,16 @@ is_live_object(rb_objspace_t *objspace, VALUE ptr)
       case T_NONE:
       case T_MOVED:
       case T_ZOMBIE:
-	return FALSE;
+        return FALSE;
       default:
         break;
     }
 
     if (!is_garbage_object(objspace, ptr)) {
-	return TRUE;
+        return TRUE;
     }
     else {
-	return FALSE;
+        return FALSE;
     }
 }
 
@@ -4541,13 +4705,13 @@ id2ref(VALUE objid)
         if ((ptr % sizeof(RVALUE)) == (4 << 2)) {
             ID symid = ptr / sizeof(RVALUE);
             p0 = (void *)ptr;
-            if (rb_id2str(symid) == 0)
+            if (!rb_static_id_valid_p(symid))
                 rb_raise(rb_eRangeError, "%p is not symbol id value", p0);
             return ID2SYM(symid);
         }
     }
 
-    if ((orig = id2ref_obj_tbl(objspace, objid)) != Qundef &&
+    if (!UNDEF_P(orig = id2ref_obj_tbl(objspace, objid)) &&
         is_live_object(objspace, orig)) {
 
         if (!rb_multi_ractor_p() || rb_ractor_shareable_p(orig)) {
@@ -4566,6 +4730,7 @@ id2ref(VALUE objid)
     }
 }
 
+/* :nodoc: */
 static VALUE
 os_id2ref(VALUE os, VALUE objid)
 {
@@ -4718,139 +4883,134 @@ obj_memsize_of(VALUE obj, int use_all_types)
     size_t size = 0;
 
     if (SPECIAL_CONST_P(obj)) {
-	return 0;
+        return 0;
     }
 
     if (FL_TEST(obj, FL_EXIVAR)) {
-	size += rb_generic_ivar_memsize(obj);
+        size += rb_generic_ivar_memsize(obj);
     }
 
     switch (BUILTIN_TYPE(obj)) {
       case T_OBJECT:
-	if (!(RBASIC(obj)->flags & ROBJECT_EMBED)) {
-	    size += ROBJECT_NUMIV(obj) * sizeof(VALUE);
-	}
-	break;
+        if (rb_shape_obj_too_complex(obj)) {
+            size += rb_st_memsize(ROBJECT_IV_HASH(obj));
+        }
+        else if (!(RBASIC(obj)->flags & ROBJECT_EMBED)) {
+            size += ROBJECT_IV_CAPACITY(obj) * sizeof(VALUE);
+        }
+        break;
       case T_MODULE:
       case T_CLASS:
-	if (RCLASS_EXT(obj)) {
+        if (RCLASS_EXT(obj)) {
             if (RCLASS_M_TBL(obj)) {
                 size += rb_id_table_memsize(RCLASS_M_TBL(obj));
             }
-	    if (RCLASS_IV_TBL(obj)) {
-		size += st_memsize(RCLASS_IV_TBL(obj));
-	    }
-	    if (RCLASS_CVC_TBL(obj)) {
-		size += rb_id_table_memsize(RCLASS_CVC_TBL(obj));
-	    }
-	    if (RCLASS_IV_INDEX_TBL(obj)) {
-                // TODO: more correct value
-		size += st_memsize(RCLASS_IV_INDEX_TBL(obj));
-	    }
-            if (RCLASS_EXT(obj)->iv_tbl) {
-                size += st_memsize(RCLASS_EXT(obj)->iv_tbl);
-	    }
+            // class IV sizes are allocated as powers of two
+            size += SIZEOF_VALUE << bit_length(RCLASS_IV_COUNT(obj));
+            if (RCLASS_CVC_TBL(obj)) {
+                size += rb_id_table_memsize(RCLASS_CVC_TBL(obj));
+            }
             if (RCLASS_EXT(obj)->const_tbl) {
                 size += rb_id_table_memsize(RCLASS_EXT(obj)->const_tbl);
-	    }
+            }
             if (RCLASS_CC_TBL(obj)) {
                 size += cc_table_memsize(RCLASS_CC_TBL(obj));
             }
             if (FL_TEST_RAW(obj, RCLASS_SUPERCLASSES_INCLUDE_SELF)) {
                 size += (RCLASS_SUPERCLASS_DEPTH(obj) + 1) * sizeof(VALUE);
             }
-#if !USE_RVARGC
-	    size += sizeof(rb_classext_t);
+#if SIZE_POOL_COUNT == 1
+            size += sizeof(rb_classext_t);
 #endif
-	}
-	break;
+        }
+        break;
       case T_ICLASS:
         if (RICLASS_OWNS_M_TBL_P(obj)) {
-	    if (RCLASS_M_TBL(obj)) {
-		size += rb_id_table_memsize(RCLASS_M_TBL(obj));
-	    }
-	}
+            if (RCLASS_M_TBL(obj)) {
+                size += rb_id_table_memsize(RCLASS_M_TBL(obj));
+            }
+        }
         if (RCLASS_EXT(obj) && RCLASS_CC_TBL(obj)) {
             size += cc_table_memsize(RCLASS_CC_TBL(obj));
         }
-	break;
+        break;
       case T_STRING:
-	size += rb_str_memsize(obj);
-	break;
+        size += rb_str_memsize(obj);
+        break;
       case T_ARRAY:
-	size += rb_ary_memsize(obj);
-	break;
+        size += rb_ary_memsize(obj);
+        break;
       case T_HASH:
         if (RHASH_AR_TABLE_P(obj)) {
             if (RHASH_AR_TABLE(obj) != NULL) {
                 size_t rb_hash_ar_table_size(void);
                 size += rb_hash_ar_table_size();
             }
-	}
+        }
         else {
             VM_ASSERT(RHASH_ST_TABLE(obj) != NULL);
             size += st_memsize(RHASH_ST_TABLE(obj));
         }
-	break;
+        break;
       case T_REGEXP:
-	if (RREGEXP_PTR(obj)) {
-	    size += onig_memsize(RREGEXP_PTR(obj));
-	}
-	break;
+        if (RREGEXP_PTR(obj)) {
+            size += onig_memsize(RREGEXP_PTR(obj));
+        }
+        break;
       case T_DATA:
-	if (use_all_types) size += rb_objspace_data_type_memsize(obj);
-	break;
+        if (use_all_types) size += rb_objspace_data_type_memsize(obj);
+        break;
       case T_MATCH:
-	if (RMATCH(obj)->rmatch) {
+        if (RMATCH(obj)->rmatch) {
             struct rmatch *rm = RMATCH(obj)->rmatch;
-	    size += onig_region_memsize(&rm->regs);
-	    size += sizeof(struct rmatch_offset) * rm->char_offset_num_allocated;
-	    size += sizeof(struct rmatch);
-	}
-	break;
+            size += onig_region_memsize(&rm->regs);
+            size += sizeof(struct rmatch_offset) * rm->char_offset_num_allocated;
+            size += sizeof(struct rmatch);
+        }
+        break;
       case T_FILE:
-	if (RFILE(obj)->fptr) {
-	    size += rb_io_memsize(RFILE(obj)->fptr);
-	}
-	break;
+        if (RFILE(obj)->fptr) {
+            size += rb_io_memsize(RFILE(obj)->fptr);
+        }
+        break;
       case T_RATIONAL:
       case T_COMPLEX:
         break;
       case T_IMEMO:
         size += imemo_memsize(obj);
-	break;
+        break;
 
       case T_FLOAT:
       case T_SYMBOL:
-	break;
+        break;
 
       case T_BIGNUM:
-	if (!(RBASIC(obj)->flags & BIGNUM_EMBED_FLAG) && BIGNUM_DIGITS(obj)) {
-	    size += BIGNUM_LEN(obj) * sizeof(BDIGIT);
-	}
-	break;
+        if (!(RBASIC(obj)->flags & BIGNUM_EMBED_FLAG) && BIGNUM_DIGITS(obj)) {
+            size += BIGNUM_LEN(obj) * sizeof(BDIGIT);
+        }
+        break;
 
       case T_NODE:
-	UNEXPECTED_NODE(obj_memsize_of);
-	break;
+        UNEXPECTED_NODE(obj_memsize_of);
+        break;
 
       case T_STRUCT:
-	if ((RBASIC(obj)->flags & RSTRUCT_EMBED_LEN_MASK) == 0 &&
-	    RSTRUCT(obj)->as.heap.ptr) {
-	    size += sizeof(VALUE) * RSTRUCT_LEN(obj);
-	}
-	break;
+        if ((RBASIC(obj)->flags & RSTRUCT_EMBED_LEN_MASK) == 0 &&
+            RSTRUCT(obj)->as.heap.ptr) {
+            size += sizeof(VALUE) * RSTRUCT_LEN(obj);
+        }
+        break;
 
       case T_ZOMBIE:
       case T_MOVED:
-	break;
+        break;
 
       default:
-	rb_bug("objspace/memsize_of(): unknown data type 0x%x(%p)",
-	       BUILTIN_TYPE(obj), (void*)obj);
+        rb_bug("objspace/memsize_of(): unknown data type 0x%x(%p)",
+               BUILTIN_TYPE(obj), (void*)obj);
     }
 
-    return size + GET_HEAP_PAGE(obj)->slot_size;
+    return size + rb_gc_obj_slot_size(obj);
 }
 
 size_t
@@ -4961,7 +5121,7 @@ count_objects(int argc, VALUE *argv, VALUE os)
     }
 
     for (i = 0; i < heap_allocated_pages; i++) {
-	struct heap_page *page = heap_pages_sorted[i];
+        struct heap_page *page = heap_pages_sorted[i];
         short stride = page->slot_size;
 
         uintptr_t p = (uintptr_t)page->start;
@@ -4970,20 +5130,19 @@ count_objects(int argc, VALUE *argv, VALUE os)
             VALUE vp = (VALUE)p;
             GC_ASSERT((NUM_IN_PAGE(vp) * BASE_SLOT_SIZE) % page->slot_size == 0);
 
-            void *poisoned = asan_poisoned_object_p(vp);
-            asan_unpoison_object(vp, false);
+            void *poisoned = asan_unpoison_object_temporary(vp);
             if (RANY(p)->as.basic.flags) {
                 counts[BUILTIN_TYPE(vp)]++;
-	    }
-	    else {
-		freed++;
-	    }
+            }
+            else {
+                freed++;
+            }
             if (poisoned) {
                 GC_ASSERT(BUILTIN_TYPE(vp) == T_NONE);
                 asan_poison_object(vp);
             }
-	}
-	total += page->total_slots;
+        }
+        total += page->total_slots;
     }
 
     if (NIL_P(hash)) {
@@ -5042,18 +5201,26 @@ gc_setup_mark_bits(struct heap_page *page)
 }
 
 static int gc_is_moveable_obj(rb_objspace_t *objspace, VALUE obj);
-static VALUE gc_move(rb_objspace_t *objspace, VALUE scan, VALUE free, size_t slot_size);
+static VALUE gc_move(rb_objspace_t *objspace, VALUE scan, VALUE free, size_t src_slot_size, size_t slot_size);
 
-static void
-lock_page_body(rb_objspace_t *objspace, struct heap_page_body *body)
-{
 #if defined(_WIN32)
-    DWORD old_protect;
+enum {HEAP_PAGE_LOCK = PAGE_NOACCESS, HEAP_PAGE_UNLOCK = PAGE_READWRITE};
 
-    if (!VirtualProtect(body, HEAP_PAGE_SIZE, PAGE_NOACCESS, &old_protect)) {
+static BOOL
+protect_page_body(struct heap_page_body *body, DWORD protect)
+{
+    DWORD old_protect;
+    return VirtualProtect(body, HEAP_PAGE_SIZE, protect, &old_protect) != 0;
+}
 #else
-    if (mprotect(body, HEAP_PAGE_SIZE, PROT_NONE)) {
+enum {HEAP_PAGE_LOCK = PROT_NONE, HEAP_PAGE_UNLOCK = PROT_READ | PROT_WRITE};
+#define protect_page_body(body, protect) !mprotect((body), HEAP_PAGE_SIZE, (protect))
 #endif
+
+static void
+lock_page_body(rb_objspace_t *objspace, struct heap_page_body *body)
+{
+    if (!protect_page_body(body, HEAP_PAGE_LOCK)) {
         rb_bug("Couldn't protect page %p, errno: %s", (void *)body, strerror(errno));
     }
     else {
@@ -5064,13 +5231,7 @@ lock_page_body(rb_objspace_t *objspace, struct heap_page_body *body)
 static void
 unlock_page_body(rb_objspace_t *objspace, struct heap_page_body *body)
 {
-#if defined(_WIN32)
-    DWORD old_protect;
-
-    if (!VirtualProtect(body, HEAP_PAGE_SIZE, PAGE_READWRITE, &old_protect)) {
-#else
-    if (mprotect(body, HEAP_PAGE_SIZE, PROT_READ | PROT_WRITE)) {
-#endif
+    if (!protect_page_body(body, HEAP_PAGE_UNLOCK)) {
         rb_bug("Couldn't unprotect page %p, errno: %s", (void *)body, strerror(errno));
     }
     else {
@@ -5081,35 +5242,43 @@ unlock_page_body(rb_objspace_t *objspace, struct heap_page_body *body)
 static bool
 try_move(rb_objspace_t *objspace, rb_heap_t *heap, struct heap_page *free_page, VALUE src)
 {
+    GC_ASSERT(gc_is_moveable_obj(objspace, src));
+
+    struct heap_page *src_page = GET_HEAP_PAGE(src);
     if (!free_page) {
         return false;
     }
 
-    /* We should return true if either src is sucessfully moved, or src is
+    /* We should return true if either src is successfully moved, or src is
      * unmoveable. A false return will cause the sweeping cursor to be
      * incremented to the next page, and src will attempt to move again */
-    if (gc_is_moveable_obj(objspace, src)) {
-        GC_ASSERT(MARKED_IN_BITMAP(GET_HEAP_MARK_BITS(src), src));
-
-        VALUE dest = (VALUE)free_page->freelist;
-        asan_unpoison_object(dest, false);
-        if (!dest) {
-            /* if we can't get something from the freelist then the page must be
-             * full */
-            return false;
-        }
-        free_page->freelist = RANY(dest)->as.free.next;
-
-        GC_ASSERT(RB_BUILTIN_TYPE(dest) == T_NONE);
-        GC_ASSERT(free_page->slot_size == GET_HEAP_PAGE(src)->slot_size);
+    GC_ASSERT(MARKED_IN_BITMAP(GET_HEAP_MARK_BITS(src), src));
+
+    asan_unlock_freelist(free_page);
+    VALUE dest = (VALUE)free_page->freelist;
+    asan_lock_freelist(free_page);
+    asan_unpoison_object(dest, false);
+    if (!dest) {
+        /* if we can't get something from the freelist then the page must be
+         * full */
+        return false;
+    }
+    free_page->freelist = RANY(dest)->as.free.next;
 
-        objspace->rcompactor.moved_count_table[BUILTIN_TYPE(src)]++;
-        objspace->rcompactor.total_moved++;
+    GC_ASSERT(RB_BUILTIN_TYPE(dest) == T_NONE);
 
-        gc_move(objspace, src, dest, free_page->slot_size);
-        gc_pin(objspace, src);
-        free_page->free_slots--;
+    if (src_page->slot_size > free_page->slot_size) {
+        objspace->rcompactor.moved_down_count_table[BUILTIN_TYPE(src)]++;
+    }
+    else if (free_page->slot_size > src_page->slot_size) {
+        objspace->rcompactor.moved_up_count_table[BUILTIN_TYPE(src)]++;
     }
+    objspace->rcompactor.moved_count_table[BUILTIN_TYPE(src)]++;
+    objspace->rcompactor.total_moved++;
+
+    gc_move(objspace, src, dest, src_page->slot_size, free_page->slot_size);
+    gc_pin(objspace, src);
+    free_page->free_slots--;
 
     return true;
 }
@@ -5128,26 +5297,45 @@ gc_unprotect_pages(rb_objspace_t *objspace, rb_heap_t *heap)
 static void gc_update_references(rb_objspace_t * objspace);
 static void invalidate_moved_page(rb_objspace_t *objspace, struct heap_page *page);
 
+#ifndef GC_CAN_COMPILE_COMPACTION
 #if defined(__wasi__) /* WebAssembly doesn't support signals */
-# define GC_COMPACTION_SUPPORTED 0
+# define GC_CAN_COMPILE_COMPACTION 0
 #else
+# define GC_CAN_COMPILE_COMPACTION 1
+#endif
+#endif
+
+#if defined(__MINGW32__) || defined(_WIN32)
 # define GC_COMPACTION_SUPPORTED 1
+#else
+/* If not MinGW, Windows, or does not have mmap, we cannot use mprotect for
+ * the read barrier, so we must disable compaction. */
+# define GC_COMPACTION_SUPPORTED (GC_CAN_COMPILE_COMPACTION && HEAP_PAGE_ALLOC_USE_MMAP)
 #endif
 
-#if GC_COMPACTION_SUPPORTED
+#if GC_CAN_COMPILE_COMPACTION
 static void
-read_barrier_handler(uintptr_t address)
+read_barrier_handler(uintptr_t original_address)
 {
     VALUE obj;
     rb_objspace_t * objspace = &rb_objspace;
 
-    address -= address % BASE_SLOT_SIZE;
+    /* Calculate address aligned to slots. */
+    uintptr_t address = original_address - (original_address % BASE_SLOT_SIZE);
 
     obj = (VALUE)address;
 
+    struct heap_page_body *page_body = GET_PAGE_BODY(obj);
+
+    /* If the page_body is NULL, then mprotect cannot handle it and will crash
+     * with "Cannot allocate memory". */
+    if (page_body == NULL) {
+        rb_bug("read_barrier_handler: segmentation fault at %p", (void *)original_address);
+    }
+
     RB_VM_LOCK_ENTER();
     {
-        unlock_page_body(objspace, GET_PAGE_BODY(obj));
+        unlock_page_body(objspace, page_body);
 
         objspace->profile.read_barrier_faults++;
 
@@ -5157,7 +5345,7 @@ read_barrier_handler(uintptr_t address)
 }
 #endif
 
-#if !GC_COMPACTION_SUPPORTED
+#if !GC_CAN_COMPILE_COMPACTION
 static void
 uninstall_handlers(void)
 {
@@ -5211,6 +5399,38 @@ install_handlers(void)
 static struct sigaction old_sigbus_handler;
 static struct sigaction old_sigsegv_handler;
 
+#ifdef HAVE_MACH_TASK_EXCEPTION_PORTS
+static exception_mask_t old_exception_masks[32];
+static mach_port_t old_exception_ports[32];
+static exception_behavior_t old_exception_behaviors[32];
+static thread_state_flavor_t old_exception_flavors[32];
+static mach_msg_type_number_t old_exception_count;
+
+static void
+disable_mach_bad_access_exc(void)
+{
+    old_exception_count = sizeof(old_exception_masks) / sizeof(old_exception_masks[0]);
+    task_swap_exception_ports(
+        mach_task_self(), EXC_MASK_BAD_ACCESS,
+        MACH_PORT_NULL, EXCEPTION_DEFAULT, 0,
+        old_exception_masks, &old_exception_count,
+        old_exception_ports, old_exception_behaviors, old_exception_flavors
+    );
+}
+
+static void
+restore_mach_bad_access_exc(void)
+{
+    for (mach_msg_type_number_t i = 0; i < old_exception_count; i++) {
+        task_set_exception_ports(
+            mach_task_self(),
+            old_exception_masks[i], old_exception_ports[i],
+            old_exception_behaviors[i], old_exception_flavors[i]
+        );
+    }
+}
+#endif
+
 static void
 read_barrier_signal(int sig, siginfo_t * info, void * data)
 {
@@ -5225,11 +5445,16 @@ read_barrier_signal(int sig, siginfo_t * info, void * data)
     sigaddset(&set, SIGBUS);
     sigaddset(&set, SIGSEGV);
     sigprocmask(SIG_UNBLOCK, &set, &prev_set);
-
+#ifdef HAVE_MACH_TASK_EXCEPTION_PORTS
+    disable_mach_bad_access_exc();
+#endif
     // run handler
     read_barrier_handler((uintptr_t)info->si_addr);
 
     // reset SEGV/BUS handlers
+#ifdef HAVE_MACH_TASK_EXCEPTION_PORTS
+    restore_mach_bad_access_exc();
+#endif
     sigaction(SIGBUS, &prev_sigbus, NULL);
     sigaction(SIGSEGV, &prev_sigsegv, NULL);
     sigprocmask(SIG_SETMASK, &prev_set, NULL);
@@ -5238,6 +5463,9 @@ read_barrier_signal(int sig, siginfo_t * info, void * data)
 static void
 uninstall_handlers(void)
 {
+#ifdef HAVE_MACH_TASK_EXCEPTION_PORTS
+    restore_mach_bad_access_exc();
+#endif
     sigaction(SIGBUS, &old_sigbus_handler, NULL);
     sigaction(SIGSEGV, &old_sigsegv_handler, NULL);
 }
@@ -5253,6 +5481,9 @@ install_handlers(void)
 
     sigaction(SIGBUS, &action, &old_sigbus_handler);
     sigaction(SIGSEGV, &action, &old_sigsegv_handler);
+#ifdef HAVE_MACH_TASK_EXCEPTION_PORTS
+    disable_mach_bad_access_exc();
+#endif
 }
 #endif
 
@@ -5404,8 +5635,7 @@ static inline void
 gc_sweep_page(rb_objspace_t *objspace, rb_heap_t *heap, struct gc_sweep_context *ctx)
 {
     struct heap_page *sweep_page = ctx->page;
-
-    int i;
+    GC_ASSERT(SIZE_POOL_EDEN_HEAP(sweep_page->size_pool) == heap);
 
     uintptr_t p;
     bits_t *bits, bitset;
@@ -5429,6 +5659,13 @@ gc_sweep_page(rb_objspace_t *objspace, rb_heap_t *heap, struct gc_sweep_context
         bits[BITMAP_INDEX(p) + page_rvalue_count / BITS_BITLENGTH] |= ~(((bits_t)1 << out_of_range_bits) - 1);
     }
 
+    /* The last bitmap plane may not be used if the last plane does not
+     * have enough space for the slot_size. In that case, the last plane must
+     * be skipped since none of the bits will be set. */
+    int bitmap_plane_count = CEILDIV(NUM_IN_PAGE(p) + page_rvalue_count, BITS_BITLENGTH);
+    GC_ASSERT(bitmap_plane_count == HEAP_PAGE_BITMAP_LIMIT - 1 ||
+                  bitmap_plane_count == HEAP_PAGE_BITMAP_LIMIT);
+
     // Skip out of range slots at the head of the page
     bitset = ~bits[0];
     bitset >>= NUM_IN_PAGE(p);
@@ -5437,7 +5674,7 @@ gc_sweep_page(rb_objspace_t *objspace, rb_heap_t *heap, struct gc_sweep_context
     }
     p += (BITS_BITLENGTH - NUM_IN_PAGE(p)) * BASE_SLOT_SIZE;
 
-    for (i=1; i < HEAP_PAGE_BITMAP_LIMIT; i++) {
+    for (int i = 1; i < bitmap_plane_count; i++) {
         bitset = ~bits[i];
         if (bitset) {
             gc_sweep_plane(objspace, heap, p, bitset, ctx);
@@ -5451,15 +5688,15 @@ gc_sweep_page(rb_objspace_t *objspace, rb_heap_t *heap, struct gc_sweep_context
 
 #if GC_PROFILE_MORE_DETAIL
     if (gc_prof_enabled(objspace)) {
-	gc_profile_record *record = gc_prof_record(objspace);
-	record->removing_objects += ctx->final_slots + ctx->freed_slots;
-	record->empty_objects += ctx->empty_slots;
+        gc_profile_record *record = gc_prof_record(objspace);
+        record->removing_objects += ctx->final_slots + ctx->freed_slots;
+        record->empty_objects += ctx->empty_slots;
     }
 #endif
     if (0) fprintf(stderr, "gc_sweep_page(%"PRIdSIZE"): total_slots: %d, freed_slots: %d, empty_slots: %d, final_slots: %d\n",
-		   rb_gc_count(),
-		   sweep_page->total_slots,
-		   ctx->freed_slots, ctx->empty_slots, ctx->final_slots);
+                   rb_gc_count(),
+                   sweep_page->total_slots,
+                   ctx->freed_slots, ctx->empty_slots, ctx->final_slots);
 
     sweep_page->free_slots += ctx->freed_slots + ctx->empty_slots;
     objspace->profile.total_freed_objects += ctx->freed_slots;
@@ -5467,17 +5704,19 @@ gc_sweep_page(rb_objspace_t *objspace, rb_heap_t *heap, struct gc_sweep_context
     if (heap_pages_deferred_final && !finalizing) {
         rb_thread_t *th = GET_THREAD();
         if (th) {
-	    gc_finalize_deferred_register(objspace);
+            gc_finalize_deferred_register(objspace);
         }
     }
 
 #if RGENGC_CHECK_MODE
     short freelist_len = 0;
+    asan_unlock_freelist(sweep_page);
     RVALUE *ptr = sweep_page->freelist;
     while (ptr) {
         freelist_len++;
         ptr = ptr->as.free.next;
     }
+    asan_lock_freelist(sweep_page);
     if (freelist_len != sweep_page->free_slots) {
         rb_bug("inconsistent freelist length: expected %d but was %d", sweep_page->free_slots, freelist_len);
     }
@@ -5535,7 +5774,7 @@ static void
 heap_page_freelist_append(struct heap_page *page, RVALUE *freelist)
 {
     if (freelist) {
-        asan_unpoison_memory_region(&page->freelist, sizeof(RVALUE*), false);
+        asan_unlock_freelist(page);
         if (page->freelist) {
             RVALUE *p = page->freelist;
             asan_unpoison_object((VALUE)p, false);
@@ -5551,7 +5790,7 @@ heap_page_freelist_append(struct heap_page *page, RVALUE *freelist)
         else {
             page->freelist = freelist;
         }
-        asan_poison_memory_region(&page->freelist, sizeof(RVALUE*));
+        asan_lock_freelist(page);
     }
 }
 
@@ -5586,8 +5825,18 @@ gc_sweep_start(rb_objspace_t *objspace)
 
     for (int i = 0; i < SIZE_POOL_COUNT; i++) {
         rb_size_pool_t *size_pool = &size_pools[i];
+        rb_heap_t *heap = SIZE_POOL_EDEN_HEAP(size_pool);
 
-        gc_sweep_start_heap(objspace, SIZE_POOL_EDEN_HEAP(size_pool));
+        gc_sweep_start_heap(objspace, heap);
+
+#if USE_RVARGC
+        /* We should call gc_sweep_finish_size_pool for size pools with no pages. */
+        if (heap->sweeping_page == NULL) {
+            GC_ASSERT(heap->total_pages == 0);
+            GC_ASSERT(heap->total_slots == 0);
+            gc_sweep_finish_size_pool(objspace, size_pool);
+        }
+#endif
     }
 
     rb_ractor_t *r = NULL;
@@ -5607,13 +5856,39 @@ gc_sweep_finish_size_pool(rb_objspace_t *objspace, rb_size_pool_t *size_pool)
 
     size_t min_free_slots = (size_t)(total_slots * gc_params.heap_free_slots_min_ratio);
 
+    /* If we don't have enough slots and we have pages on the tomb heap, move
+     * pages from the tomb heap to the eden heap. This may prevent page
+     * creation thrashing (frequently allocating and deallocting pages) and
+     * GC thrashing (running GC more frequently than required). */
+    struct heap_page *resurrected_page;
+    while ((swept_slots < min_free_slots || swept_slots < gc_params.heap_init_slots) &&
+            (resurrected_page = heap_page_resurrect(objspace, size_pool))) {
+        swept_slots += resurrected_page->free_slots;
+
+        heap_add_page(objspace, size_pool, heap, resurrected_page);
+        heap_add_freepage(heap, resurrected_page);
+    }
+
+    /* Some size pools may have very few pages (or even no pages). These size pools
+     * should still have allocatable pages. */
+    if (min_free_slots < gc_params.heap_init_slots && swept_slots < gc_params.heap_init_slots) {
+        int multiple = size_pool->slot_size / BASE_SLOT_SIZE;
+        size_t extra_slots = gc_params.heap_init_slots - swept_slots;
+        size_t extend_page_count = CEILDIV(extra_slots * multiple, HEAP_PAGE_OBJ_LIMIT);
+        if (extend_page_count > size_pool->allocatable_pages) {
+            size_pool_allocatable_pages_set(objspace, size_pool, extend_page_count);
+        }
+    }
+
     if (swept_slots < min_free_slots) {
         bool grow_heap = is_full_marking(objspace);
 
         if (!is_full_marking(objspace)) {
-            /* The heap is a growth heap if it freed more slots than had empty slots. */
-            bool is_growth_heap = size_pool->empty_slots == 0 ||
-                                    size_pool->freed_slots > size_pool->empty_slots;
+            /* The heap is a growth heap if it freed more slots than had empty
+             * slots and used up all of its allocatable pages. */
+            bool is_growth_heap = (size_pool->empty_slots == 0 ||
+                                       size_pool->freed_slots > size_pool->empty_slots) &&
+                                   size_pool->allocatable_pages == 0;
 
             if (objspace->profile.count - objspace->rgengc.last_major_gc < RVALUE_OLD_AGE) {
                 grow_heap = TRUE;
@@ -5625,13 +5900,11 @@ gc_sweep_finish_size_pool(rb_objspace_t *objspace, rb_size_pool_t *size_pool)
         }
 
         if (grow_heap) {
-            size_t extend_page_count = heap_extend_pages(objspace, swept_slots, total_slots, total_pages);
+            size_t extend_page_count = heap_extend_pages(objspace, size_pool, swept_slots, total_slots, total_pages);
 
             if (extend_page_count > size_pool->allocatable_pages) {
                 size_pool_allocatable_pages_set(objspace, size_pool, extend_page_count);
             }
-
-            heap_increment(objspace, size_pool, SIZE_POOL_EDEN_HEAP(size_pool));
         }
     }
 }
@@ -5720,41 +5993,41 @@ gc_sweep_step(rb_objspace_t *objspace, rb_size_pool_t *size_pool, rb_heap_t *hea
 
         heap->sweeping_page = ccan_list_next(&heap->pages, sweep_page, page_node);
 
-	if (sweep_page->final_slots + free_slots == sweep_page->total_slots &&
-	    heap_pages_freeable_pages > 0 &&
-	    unlink_limit > 0) {
-	    heap_pages_freeable_pages--;
-	    unlink_limit--;
-	    /* there are no living objects -> move this page to tomb heap */
-	    heap_unlink_page(objspace, heap, sweep_page);
-	    heap_add_page(objspace, size_pool, SIZE_POOL_TOMB_HEAP(size_pool), sweep_page);
-	}
-	else if (free_slots > 0) {
+        if (sweep_page->final_slots + free_slots == sweep_page->total_slots &&
+            heap_pages_freeable_pages > 0 &&
+            unlink_limit > 0) {
+            heap_pages_freeable_pages--;
+            unlink_limit--;
+            /* there are no living objects -> move this page to tomb heap */
+            heap_unlink_page(objspace, heap, sweep_page);
+            heap_add_page(objspace, size_pool, SIZE_POOL_TOMB_HEAP(size_pool), sweep_page);
+        }
+        else if (free_slots > 0) {
 #if USE_RVARGC
             size_pool->freed_slots += ctx.freed_slots;
             size_pool->empty_slots += ctx.empty_slots;
 #endif
 
 #if GC_ENABLE_INCREMENTAL_MARK
-	    if (need_pool) {
+            if (need_pool) {
                 heap_add_poolpage(objspace, heap, sweep_page);
                 need_pool = FALSE;
-	    }
-	    else {
+            }
+            else {
                 heap_add_freepage(heap, sweep_page);
                 swept_slots += free_slots;
                 if (swept_slots > GC_INCREMENTAL_SWEEP_SLOT_COUNT) {
                     break;
                 }
-	    }
+            }
 #else
             heap_add_freepage(heap, sweep_page);
             break;
 #endif
-	}
-	else {
-	    sweep_page->free_next = NULL;
-	}
+        }
+        else {
+            sweep_page->free_next = NULL;
+        }
     } while ((sweep_page = heap->sweeping_page));
 
     if (!heap->sweeping_page) {
@@ -5834,9 +6107,19 @@ invalidate_moved_plane(rb_objspace_t *objspace, struct heap_page *page, uintptr_
 
                     object = rb_gc_location(forwarding_object);
 
-                    gc_move(objspace, object, forwarding_object, page->slot_size);
+                    shape_id_t original_shape_id = 0;
+                    if (RB_TYPE_P(object, T_OBJECT)) {
+                        original_shape_id = RMOVED(forwarding_object)->original_shape_id;
+                    }
+
+                    gc_move(objspace, object, forwarding_object, GET_HEAP_PAGE(object)->slot_size, page->slot_size);
                     /* forwarding_object is now our actual object, and "object"
                      * is the free slot for the original page */
+
+                    if (original_shape_id) {
+                        ROBJECT_SET_SHAPE_ID(forwarding_object, original_shape_id);
+                    }
+
                     struct heap_page *orig_page = GET_HEAP_PAGE(object);
                     orig_page->free_slots++;
                     heap_page_add_freeobj(objspace, orig_page, object);
@@ -5903,6 +6186,8 @@ gc_compact_start(rb_objspace_t *objspace)
 
     memset(objspace->rcompactor.considered_count_table, 0, T_MASK * sizeof(size_t));
     memset(objspace->rcompactor.moved_count_table, 0, T_MASK * sizeof(size_t));
+    memset(objspace->rcompactor.moved_up_count_table, 0, T_MASK * sizeof(size_t));
+    memset(objspace->rcompactor.moved_down_count_table, 0, T_MASK * sizeof(size_t));
 
     /* Set up read barrier for pages containing MOVED objects */
     install_handlers();
@@ -5924,11 +6209,11 @@ gc_sweep(rb_objspace_t *objspace)
 
     if (immediate_sweep) {
 #if !GC_ENABLE_LAZY_SWEEP
-	gc_prof_sweep_timer_start(objspace);
+        gc_prof_sweep_timer_start(objspace);
 #endif
-	gc_sweep_rest(objspace);
+        gc_sweep_rest(objspace);
 #if !GC_ENABLE_LAZY_SWEEP
-	gc_prof_sweep_timer_stop(objspace);
+        gc_prof_sweep_timer_stop(objspace);
 #endif
     }
     else {
@@ -5973,8 +6258,8 @@ mark_stack_size(mark_stack_t *stack)
     stack_chunk_t *chunk = stack->chunk ? stack->chunk->next : NULL;
 
     while (chunk) {
-	size += stack->limit;
-	chunk = chunk->next;
+        size += stack->limit;
+        chunk = chunk->next;
     }
     return size;
 }
@@ -6099,11 +6384,11 @@ push_mark_stack(mark_stack_t *stack, VALUE data)
       case T_ZOMBIE:
       case T_UNDEF:
       case T_MASK:
-	rb_bug("push_mark_stack() called for broken object");
-	break;
+        rb_bug("push_mark_stack() called for broken object");
+        break;
 
       case T_NODE:
-	UNEXPECTED_NODE(push_mark_stack);
+        UNEXPECTED_NODE(push_mark_stack);
         break;
     }
 
@@ -6123,7 +6408,7 @@ pop_mark_stack(mark_stack_t *stack, VALUE *data)
         pop_mark_stack_chunk(stack);
     }
     else {
-	*data = stack->chunk->data[--stack->index];
+        *data = stack->chunk->data[--stack->index];
     }
     return TRUE;
 }
@@ -6156,7 +6441,7 @@ init_mark_stack(mark_stack_t *stack)
 # define STACK_LENGTH  (size_t)(STACK_END - STACK_START + 1)
 #else
 # define STACK_LENGTH  ((STACK_END < STACK_START) ? (size_t)(STACK_START - STACK_END) \
-			: (size_t)(STACK_END - STACK_START + 1))
+                        : (size_t)(STACK_END - STACK_START + 1))
 #endif
 #if !STACK_GROW_DIRECTION
 int ruby_stack_grow_direction;
@@ -6225,7 +6510,7 @@ each_location(rb_objspace_t *objspace, register const VALUE *x, register long n,
     while (n--) {
         v = *x;
         cb(objspace, v);
-	x++;
+        x++;
     }
 }
 
@@ -6424,7 +6709,7 @@ mark_method_entry(rb_objspace_t *objspace, const rb_method_entry_t *me)
     gc_mark(objspace, me->defined_class);
 
     if (def) {
-	switch (def->type) {
+        switch (def->type) {
           case VM_METHOD_TYPE_ISEQ:
             if (def->body.iseq.iseqptr) gc_mark(objspace, (VALUE)def->body.iseq.iseqptr);
             gc_mark(objspace, (VALUE)def->body.iseq.cref);
@@ -6435,29 +6720,29 @@ mark_method_entry(rb_objspace_t *objspace, const rb_method_entry_t *me)
                 gc_mark_and_pin(objspace, (VALUE)me);
             }
             break;
-	  case VM_METHOD_TYPE_ATTRSET:
-	  case VM_METHOD_TYPE_IVAR:
-	    gc_mark(objspace, def->body.attr.location);
-	    break;
-	  case VM_METHOD_TYPE_BMETHOD:
+          case VM_METHOD_TYPE_ATTRSET:
+          case VM_METHOD_TYPE_IVAR:
+            gc_mark(objspace, def->body.attr.location);
+            break;
+          case VM_METHOD_TYPE_BMETHOD:
             gc_mark(objspace, def->body.bmethod.proc);
             if (def->body.bmethod.hooks) rb_hook_list_mark(def->body.bmethod.hooks);
-	    break;
-	  case VM_METHOD_TYPE_ALIAS:
-	    gc_mark(objspace, (VALUE)def->body.alias.original_me);
-	    return;
-	  case VM_METHOD_TYPE_REFINED:
-	    gc_mark(objspace, (VALUE)def->body.refined.orig_me);
-	    gc_mark(objspace, (VALUE)def->body.refined.owner);
-	    break;
-	  case VM_METHOD_TYPE_CFUNC:
-	  case VM_METHOD_TYPE_ZSUPER:
-	  case VM_METHOD_TYPE_MISSING:
-	  case VM_METHOD_TYPE_OPTIMIZED:
-	  case VM_METHOD_TYPE_UNDEF:
-	  case VM_METHOD_TYPE_NOTIMPLEMENTED:
-	    break;
-	}
+            break;
+          case VM_METHOD_TYPE_ALIAS:
+            gc_mark(objspace, (VALUE)def->body.alias.original_me);
+            return;
+          case VM_METHOD_TYPE_REFINED:
+            gc_mark(objspace, (VALUE)def->body.refined.orig_me);
+            gc_mark(objspace, (VALUE)def->body.refined.owner);
+            break;
+          case VM_METHOD_TYPE_CFUNC:
+          case VM_METHOD_TYPE_ZSUPER:
+          case VM_METHOD_TYPE_MISSING:
+          case VM_METHOD_TYPE_OPTIMIZED:
+          case VM_METHOD_TYPE_UNDEF:
+          case VM_METHOD_TYPE_NOTIMPLEMENTED:
+            break;
+        }
     }
 }
 
@@ -6474,7 +6759,7 @@ static void
 mark_m_tbl(rb_objspace_t *objspace, struct rb_id_table *tbl)
 {
     if (tbl) {
-	rb_id_table_foreach_values(tbl, mark_method_entry_i, objspace);
+        rb_id_table_foreach_values(tbl, mark_method_entry_i, objspace);
     }
 }
 
@@ -6537,8 +6822,10 @@ mark_current_machine_context(rb_objspace_t *objspace, rb_execution_context_t *ec
 static void
 mark_current_machine_context(rb_objspace_t *objspace, rb_execution_context_t *ec)
 {
-    rb_wasm_scan_stack(rb_mark_locations);
-    each_stack_location(objspace, ec, rb_stack_range_tmp[0], rb_stack_range_tmp[1], gc_mark_maybe);
+    VALUE *stack_start, *stack_end;
+    SET_STACK_END;
+    GET_STACK_BOUNDS(stack_start, stack_end, 1);
+    each_stack_location(objspace, ec, stack_start, stack_end, gc_mark_maybe);
 
     rb_wasm_scan_locals(rb_mark_locations);
     each_stack_location(objspace, ec, rb_stack_range_tmp[0], rb_stack_range_tmp[1], gc_mark_maybe);
@@ -6552,8 +6839,8 @@ static void
 mark_current_machine_context(rb_objspace_t *objspace, rb_execution_context_t *ec)
 {
     union {
-	rb_jmp_buf j;
-	VALUE v[sizeof(rb_jmp_buf) / (sizeof(VALUE))];
+        rb_jmp_buf j;
+        VALUE v[sizeof(rb_jmp_buf) / (sizeof(VALUE))];
     } save_regs_gc_mark;
     VALUE *stack_start, *stack_end;
 
@@ -6592,15 +6879,15 @@ rb_gc_mark_machine_stack(const rb_execution_context_t *ec)
 
 static void
 each_stack_location(rb_objspace_t *objspace, const rb_execution_context_t *ec,
-		     const VALUE *stack_start, const VALUE *stack_end, void (*cb)(rb_objspace_t *, VALUE))
+                     const VALUE *stack_start, const VALUE *stack_end, void (*cb)(rb_objspace_t *, VALUE))
 {
 
     gc_mark_locations(objspace, stack_start, stack_end, cb);
 
 #if defined(__mc68000__)
     gc_mark_locations(objspace,
-		      (VALUE*)((char*)stack_start + 2),
-		      (VALUE*)((char*)stack_end - 2), cb);
+                      (VALUE*)((char*)stack_start + 2),
+                      (VALUE*)((char*)stack_end - 2), cb);
 #endif
 }
 
@@ -6622,8 +6909,7 @@ gc_mark_maybe(rb_objspace_t *objspace, VALUE obj)
     (void)VALGRIND_MAKE_MEM_DEFINED(&obj, sizeof(obj));
 
     if (is_pointer_to_heap(objspace, (void *)obj)) {
-        void *ptr = __asan_region_is_poisoned((void *)obj, SIZEOF_VALUE);
-        asan_unpoison_object(obj, false);
+        void *ptr = asan_unpoison_object_temporary(obj);
 
         /* Garbage can live on the stack, so do not mark or pin */
         switch (BUILTIN_TYPE(obj)) {
@@ -6664,20 +6950,20 @@ gc_remember_unprotected(rb_objspace_t *objspace, VALUE obj)
     bits_t *uncollectible_bits = &page->uncollectible_bits[0];
 
     if (!MARKED_IN_BITMAP(uncollectible_bits, obj)) {
-	page->flags.has_uncollectible_shady_objects = TRUE;
-	MARK_IN_BITMAP(uncollectible_bits, obj);
-	objspace->rgengc.uncollectible_wb_unprotected_objects++;
+        page->flags.has_uncollectible_shady_objects = TRUE;
+        MARK_IN_BITMAP(uncollectible_bits, obj);
+        objspace->rgengc.uncollectible_wb_unprotected_objects++;
 
 #if RGENGC_PROFILE > 0
-	objspace->profile.total_remembered_shady_object_count++;
+        objspace->profile.total_remembered_shady_object_count++;
 #if RGENGC_PROFILE >= 2
-	objspace->profile.remembered_shady_object_count_types[BUILTIN_TYPE(obj)]++;
+        objspace->profile.remembered_shady_object_count_types[BUILTIN_TYPE(obj)]++;
 #endif
 #endif
-	return TRUE;
+        return TRUE;
     }
     else {
-	return FALSE;
+        return FALSE;
     }
 }
 
@@ -6687,32 +6973,32 @@ rgengc_check_relation(rb_objspace_t *objspace, VALUE obj)
     const VALUE old_parent = objspace->rgengc.parent_object;
 
     if (old_parent) { /* parent object is old */
-	if (RVALUE_WB_UNPROTECTED(obj)) {
-	    if (gc_remember_unprotected(objspace, obj)) {
-		gc_report(2, objspace, "relation: (O->S) %s -> %s\n", obj_info(old_parent), obj_info(obj));
-	    }
-	}
-	else {
-	    if (!RVALUE_OLD_P(obj)) {
-		if (RVALUE_MARKED(obj)) {
-		    /* An object pointed from an OLD object should be OLD. */
-		    gc_report(2, objspace, "relation: (O->unmarked Y) %s -> %s\n", obj_info(old_parent), obj_info(obj));
-		    RVALUE_AGE_SET_OLD(objspace, obj);
-		    if (is_incremental_marking(objspace)) {
-			if (!RVALUE_MARKING(obj)) {
-			    gc_grey(objspace, obj);
-			}
-		    }
-		    else {
-			rgengc_remember(objspace, obj);
-		    }
-		}
-		else {
-		    gc_report(2, objspace, "relation: (O->Y) %s -> %s\n", obj_info(old_parent), obj_info(obj));
-		    RVALUE_AGE_SET_CANDIDATE(objspace, obj);
-		}
-	    }
-	}
+        if (RVALUE_WB_UNPROTECTED(obj)) {
+            if (gc_remember_unprotected(objspace, obj)) {
+                gc_report(2, objspace, "relation: (O->S) %s -> %s\n", obj_info(old_parent), obj_info(obj));
+            }
+        }
+        else {
+            if (!RVALUE_OLD_P(obj)) {
+                if (RVALUE_MARKED(obj)) {
+                    /* An object pointed from an OLD object should be OLD. */
+                    gc_report(2, objspace, "relation: (O->unmarked Y) %s -> %s\n", obj_info(old_parent), obj_info(obj));
+                    RVALUE_AGE_SET_OLD(objspace, obj);
+                    if (is_incremental_marking(objspace)) {
+                        if (!RVALUE_MARKING(obj)) {
+                            gc_grey(objspace, obj);
+                        }
+                    }
+                    else {
+                        rgengc_remember(objspace, obj);
+                    }
+                }
+                else {
+                    gc_report(2, objspace, "relation: (O->Y) %s -> %s\n", obj_info(old_parent), obj_info(obj));
+                    RVALUE_AGE_SET_CANDIDATE(objspace, obj);
+                }
+            }
+        }
     }
 
     GC_ASSERT(old_parent == objspace->rgengc.parent_object);
@@ -6728,7 +7014,7 @@ gc_grey(rb_objspace_t *objspace, VALUE obj)
 
 #if GC_ENABLE_INCREMENTAL_MARK
     if (is_incremental_marking(objspace)) {
-	MARK_IN_BITMAP(GET_HEAP_MARKING_BITS(obj), obj);
+        MARK_IN_BITMAP(GET_HEAP_MARKING_BITS(obj), obj);
     }
 #endif
 
@@ -6744,14 +7030,14 @@ gc_aging(rb_objspace_t *objspace, VALUE obj)
     check_rvalue_consistency(obj);
 
     if (!RVALUE_PAGE_WB_UNPROTECTED(page, obj)) {
-	if (!RVALUE_OLD_P(obj)) {
-	    gc_report(3, objspace, "gc_aging: YOUNG: %s\n", obj_info(obj));
-	    RVALUE_AGE_INC(objspace, obj);
-	}
-	else if (is_full_marking(objspace)) {
-	    GC_ASSERT(RVALUE_PAGE_UNCOLLECTIBLE(page, obj) == FALSE);
-	    RVALUE_PAGE_OLD_UNCOLLECTIBLE_SET(objspace, page, obj);
-	}
+        if (!RVALUE_OLD_P(obj)) {
+            gc_report(3, objspace, "gc_aging: YOUNG: %s\n", obj_info(obj));
+            RVALUE_AGE_INC(objspace, obj);
+        }
+        else if (is_full_marking(objspace)) {
+            GC_ASSERT(RVALUE_PAGE_UNCOLLECTIBLE(page, obj) == FALSE);
+            RVALUE_PAGE_OLD_UNCOLLECTIBLE_SET(objspace, page, obj);
+        }
     }
     check_rvalue_consistency(obj);
 
@@ -6765,8 +7051,8 @@ static void
 gc_mark_ptr(rb_objspace_t *objspace, VALUE obj)
 {
     if (LIKELY(during_gc)) {
-	rgengc_check_relation(objspace, obj);
-	if (!gc_mark_set(objspace, obj)) return; /* already marked */
+        rgengc_check_relation(objspace, obj);
+        if (!gc_mark_set(objspace, obj)) return; /* already marked */
 
         if (0) { // for debug GC marking miss
             if (objspace->rgengc.parent_object) {
@@ -6783,8 +7069,8 @@ gc_mark_ptr(rb_objspace_t *objspace, VALUE obj)
             rp(obj);
             rb_bug("try to mark T_NONE object"); /* check here will help debugging */
         }
-	gc_aging(objspace, obj);
-	gc_grey(objspace, obj);
+        gc_aging(objspace, obj);
+        gc_grey(objspace, obj);
     }
     else {
         reachable_objects_from_callback(obj);
@@ -6843,10 +7129,10 @@ static inline void
 gc_mark_set_parent(rb_objspace_t *objspace, VALUE obj)
 {
     if (RVALUE_OLD_P(obj)) {
-	objspace->rgengc.parent_object = obj;
+        objspace->rgengc.parent_object = obj;
     }
     else {
-	objspace->rgengc.parent_object = Qfalse;
+        objspace->rgengc.parent_object = Qfalse;
     }
 }
 
@@ -6855,8 +7141,8 @@ gc_mark_imemo(rb_objspace_t *objspace, VALUE obj)
 {
     switch (imemo_type(obj)) {
       case imemo_env:
-	{
-	    const rb_env_t *env = (const rb_env_t *)obj;
+        {
+            const rb_env_t *env = (const rb_env_t *)obj;
 
             if (LIKELY(env->ep)) {
                 // just after newobj() can be NULL here.
@@ -6867,50 +7153,50 @@ gc_mark_imemo(rb_objspace_t *objspace, VALUE obj)
                 gc_mark(objspace, (VALUE)rb_vm_env_prev_env(env));
                 gc_mark(objspace, (VALUE)env->iseq);
             }
-	}
-	return;
+        }
+        return;
       case imemo_cref:
-	gc_mark(objspace, RANY(obj)->as.imemo.cref.klass_or_self);
-	gc_mark(objspace, (VALUE)RANY(obj)->as.imemo.cref.next);
-	gc_mark(objspace, RANY(obj)->as.imemo.cref.refinements);
-	return;
+        gc_mark(objspace, RANY(obj)->as.imemo.cref.klass_or_self);
+        gc_mark(objspace, (VALUE)RANY(obj)->as.imemo.cref.next);
+        gc_mark(objspace, RANY(obj)->as.imemo.cref.refinements);
+        return;
       case imemo_svar:
-	gc_mark(objspace, RANY(obj)->as.imemo.svar.cref_or_me);
-	gc_mark(objspace, RANY(obj)->as.imemo.svar.lastline);
-	gc_mark(objspace, RANY(obj)->as.imemo.svar.backref);
-	gc_mark(objspace, RANY(obj)->as.imemo.svar.others);
-	return;
+        gc_mark(objspace, RANY(obj)->as.imemo.svar.cref_or_me);
+        gc_mark(objspace, RANY(obj)->as.imemo.svar.lastline);
+        gc_mark(objspace, RANY(obj)->as.imemo.svar.backref);
+        gc_mark(objspace, RANY(obj)->as.imemo.svar.others);
+        return;
       case imemo_throw_data:
-	gc_mark(objspace, RANY(obj)->as.imemo.throw_data.throw_obj);
-	return;
+        gc_mark(objspace, RANY(obj)->as.imemo.throw_data.throw_obj);
+        return;
       case imemo_ifunc:
-	gc_mark_maybe(objspace, (VALUE)RANY(obj)->as.imemo.ifunc.data);
-	return;
+        gc_mark_maybe(objspace, (VALUE)RANY(obj)->as.imemo.ifunc.data);
+        return;
       case imemo_memo:
-	gc_mark(objspace, RANY(obj)->as.imemo.memo.v1);
-	gc_mark(objspace, RANY(obj)->as.imemo.memo.v2);
-	gc_mark_maybe(objspace, RANY(obj)->as.imemo.memo.u3.value);
-	return;
+        gc_mark(objspace, RANY(obj)->as.imemo.memo.v1);
+        gc_mark(objspace, RANY(obj)->as.imemo.memo.v2);
+        gc_mark_maybe(objspace, RANY(obj)->as.imemo.memo.u3.value);
+        return;
       case imemo_ment:
-	mark_method_entry(objspace, &RANY(obj)->as.imemo.ment);
-	return;
+        mark_method_entry(objspace, &RANY(obj)->as.imemo.ment);
+        return;
       case imemo_iseq:
-	rb_iseq_mark((rb_iseq_t *)obj);
-	return;
+        rb_iseq_mark((rb_iseq_t *)obj);
+        return;
       case imemo_tmpbuf:
-	{
-	    const rb_imemo_tmpbuf_t *m = &RANY(obj)->as.imemo.alloc;
-	    do {
-		rb_gc_mark_locations(m->ptr, m->ptr + m->cnt);
-	    } while ((m = m->next) != NULL);
-	}
-	return;
+        {
+            const rb_imemo_tmpbuf_t *m = &RANY(obj)->as.imemo.alloc;
+            do {
+                rb_gc_mark_locations(m->ptr, m->ptr + m->cnt);
+            } while ((m = m->next) != NULL);
+        }
+        return;
       case imemo_ast:
-	rb_ast_mark(&RANY(obj)->as.imemo.ast);
-	return;
+        rb_ast_mark(&RANY(obj)->as.imemo.ast);
+        return;
       case imemo_parser_strterm:
-	rb_strterm_mark(obj);
-	return;
+        rb_strterm_mark(obj);
+        return;
       case imemo_callinfo:
         return;
       case imemo_callcache:
@@ -6928,11 +7214,13 @@ gc_mark_imemo(rb_objspace_t *objspace, VALUE obj)
         return;
 #if VM_CHECK_MODE > 0
       default:
-	VM_UNREACHABLE(gc_mark_imemo);
+        VM_UNREACHABLE(gc_mark_imemo);
 #endif
     }
 }
 
+static void mark_cvc_tbl(rb_objspace_t *objspace, VALUE klass);
+
 static void
 gc_mark_children(rb_objspace_t *objspace, VALUE obj)
 {
@@ -6940,7 +7228,7 @@ gc_mark_children(rb_objspace_t *objspace, VALUE obj)
     gc_mark_set_parent(objspace, obj);
 
     if (FL_TEST(obj, FL_EXIVAR)) {
-	rb_mark_generic_ivar(obj);
+        rb_mark_generic_ivar(obj);
     }
 
     switch (BUILTIN_TYPE(obj)) {
@@ -6953,16 +7241,16 @@ gc_mark_children(rb_objspace_t *objspace, VALUE obj)
 
       case T_NIL:
       case T_FIXNUM:
-	rb_bug("rb_gc_mark() called for broken object");
-	break;
+        rb_bug("rb_gc_mark() called for broken object");
+        break;
 
       case T_NODE:
-	UNEXPECTED_NODE(rb_gc_mark);
-	break;
+        UNEXPECTED_NODE(rb_gc_mark);
+        break;
 
       case T_IMEMO:
-	gc_mark_imemo(objspace, obj);
-	return;
+        gc_mark_imemo(objspace, obj);
+        return;
 
       default:
         break;
@@ -6976,84 +7264,105 @@ gc_mark_children(rb_objspace_t *objspace, VALUE obj)
         if (RCLASS_SUPER(obj)) {
             gc_mark(objspace, RCLASS_SUPER(obj));
         }
-	if (!RCLASS_EXT(obj)) break;
+        if (!RCLASS_EXT(obj)) break;
 
         mark_m_tbl(objspace, RCLASS_M_TBL(obj));
+        mark_cvc_tbl(objspace, obj);
         cc_table_mark(objspace, obj);
-        mark_tbl_no_pin(objspace, RCLASS_IV_TBL(obj));
-	mark_const_tbl(objspace, RCLASS_CONST_TBL(obj));
-	break;
+        for (attr_index_t i = 0; i < RCLASS_IV_COUNT(obj); i++) {
+            gc_mark(objspace, RCLASS_IVPTR(obj)[i]);
+        }
+        mark_const_tbl(objspace, RCLASS_CONST_TBL(obj));
+        break;
 
       case T_ICLASS:
         if (RICLASS_OWNS_M_TBL_P(obj)) {
-	    mark_m_tbl(objspace, RCLASS_M_TBL(obj));
-	}
+            mark_m_tbl(objspace, RCLASS_M_TBL(obj));
+        }
         if (RCLASS_SUPER(obj)) {
             gc_mark(objspace, RCLASS_SUPER(obj));
         }
-	if (!RCLASS_EXT(obj)) break;
-	mark_m_tbl(objspace, RCLASS_CALLABLE_M_TBL(obj));
+        if (!RCLASS_EXT(obj)) break;
+
+        if (RCLASS_INCLUDER(obj)) {
+            gc_mark(objspace, RCLASS_INCLUDER(obj));
+        }
+        mark_m_tbl(objspace, RCLASS_CALLABLE_M_TBL(obj));
         cc_table_mark(objspace, obj);
-	break;
+        break;
 
       case T_ARRAY:
-        if (FL_TEST(obj, ELTS_SHARED)) {
-            VALUE root = any->as.array.as.heap.aux.shared_root;
+        if (ARY_SHARED_P(obj)) {
+            VALUE root = ARY_SHARED_ROOT(obj);
             gc_mark(objspace, root);
-	}
-	else {
-	    long i, len = RARRAY_LEN(obj);
+        }
+        else {
+            long i, len = RARRAY_LEN(obj);
             const VALUE *ptr = RARRAY_CONST_PTR_TRANSIENT(obj);
-	    for (i=0; i < len; i++) {
+            for (i=0; i < len; i++) {
                 gc_mark(objspace, ptr[i]);
-	    }
+            }
 
             if (LIKELY(during_gc)) {
-                if (!FL_TEST_RAW(obj, RARRAY_EMBED_FLAG) &&
-                    RARRAY_TRANSIENT_P(obj)) {
+                if (!ARY_EMBED_P(obj) && RARRAY_TRANSIENT_P(obj)) {
                     rb_transient_heap_mark(obj, ptr);
                 }
             }
         }
-	break;
+        break;
 
       case T_HASH:
         mark_hash(objspace, obj);
-	break;
+        break;
 
       case T_STRING:
-	if (STR_SHARED_P(obj)) {
-	    gc_mark(objspace, any->as.string.as.heap.aux.shared);
-	}
-	break;
+        if (STR_SHARED_P(obj)) {
+            gc_mark(objspace, any->as.string.as.heap.aux.shared);
+        }
+        break;
 
       case T_DATA:
-	{
-	    void *const ptr = DATA_PTR(obj);
-	    if (ptr) {
-		RUBY_DATA_FUNC mark_func = RTYPEDDATA_P(obj) ?
-		    any->as.typeddata.type->function.dmark :
-		    any->as.data.dmark;
-		if (mark_func) (*mark_func)(ptr);
-	    }
-	}
-	break;
+        {
+            void *const ptr = DATA_PTR(obj);
+            if (ptr) {
+                RUBY_DATA_FUNC mark_func = RTYPEDDATA_P(obj) ?
+                    any->as.typeddata.type->function.dmark :
+                    any->as.data.dmark;
+                if (mark_func) (*mark_func)(ptr);
+            }
+        }
+        break;
 
       case T_OBJECT:
         {
-            const VALUE * const ptr = ROBJECT_IVPTR(obj);
+            rb_shape_t *shape = rb_shape_get_shape_by_id(ROBJECT_SHAPE_ID(obj));
+            if (rb_shape_obj_too_complex(obj)) {
+                mark_tbl_no_pin(objspace, ROBJECT_IV_HASH(obj));
+            }
+            else {
+                const VALUE * const ptr = ROBJECT_IVPTR(obj);
 
-            uint32_t i, len = ROBJECT_NUMIV(obj);
-            for (i  = 0; i < len; i++) {
-                gc_mark(objspace, ptr[i]);
+                uint32_t i, len = ROBJECT_IV_COUNT(obj);
+                for (i  = 0; i < len; i++) {
+                    gc_mark(objspace, ptr[i]);
+                }
+
+                if (LIKELY(during_gc) &&
+                        ROBJ_TRANSIENT_P(obj)) {
+                    rb_transient_heap_mark(obj, ptr);
+                }
             }
+            if (shape) {
+                VALUE klass = RBASIC_CLASS(obj);
 
-            if (LIKELY(during_gc) &&
-                    ROBJ_TRANSIENT_P(obj)) {
-                rb_transient_heap_mark(obj, ptr);
+                // Increment max_iv_count if applicable, used to determine size pool allocation
+                uint32_t num_of_ivs = shape->next_iv_index;
+                if (RCLASS_EXT(klass)->max_iv_count < num_of_ivs) {
+                    RCLASS_EXT(klass)->max_iv_count = num_of_ivs;
+                }
             }
         }
-	break;
+        break;
 
       case T_FILE:
         if (any->as.file.fptr) {
@@ -7064,32 +7373,33 @@ gc_mark_children(rb_objspace_t *objspace, VALUE obj)
             gc_mark(objspace, any->as.file.fptr->writeconv_pre_ecopts);
             gc_mark(objspace, any->as.file.fptr->encs.ecopts);
             gc_mark(objspace, any->as.file.fptr->write_lock);
+            gc_mark(objspace, any->as.file.fptr->timeout);
         }
         break;
 
       case T_REGEXP:
         gc_mark(objspace, any->as.regexp.src);
-	break;
+        break;
 
       case T_MATCH:
-	gc_mark(objspace, any->as.match.regexp);
-	if (any->as.match.str) {
-	    gc_mark(objspace, any->as.match.str);
-	}
-	break;
+        gc_mark(objspace, any->as.match.regexp);
+        if (any->as.match.str) {
+            gc_mark(objspace, any->as.match.str);
+        }
+        break;
 
       case T_RATIONAL:
-	gc_mark(objspace, any->as.rational.num);
-	gc_mark(objspace, any->as.rational.den);
-	break;
+        gc_mark(objspace, any->as.rational.num);
+        gc_mark(objspace, any->as.rational.den);
+        break;
 
       case T_COMPLEX:
-	gc_mark(objspace, any->as.complex.real);
-	gc_mark(objspace, any->as.complex.imag);
-	break;
+        gc_mark(objspace, any->as.complex.real);
+        gc_mark(objspace, any->as.complex.imag);
+        break;
 
       case T_STRUCT:
-	{
+        {
             long i;
             const long len = RSTRUCT_LEN(obj);
             const VALUE * const ptr = RSTRUCT_CONST_PTR(obj);
@@ -7102,19 +7412,19 @@ gc_mark_children(rb_objspace_t *objspace, VALUE obj)
                 RSTRUCT_TRANSIENT_P(obj)) {
                 rb_transient_heap_mark(obj, ptr);
             }
-	}
-	break;
+        }
+        break;
 
       default:
 #if GC_DEBUG
-	rb_gcdebug_print_obj_condition((VALUE)obj);
+        rb_gcdebug_print_obj_condition((VALUE)obj);
 #endif
         if (BUILTIN_TYPE(obj) == T_MOVED)   rb_bug("rb_gc_mark(): %p is T_MOVED", (void *)obj);
-	if (BUILTIN_TYPE(obj) == T_NONE)   rb_bug("rb_gc_mark(): %p is T_NONE", (void *)obj);
-	if (BUILTIN_TYPE(obj) == T_ZOMBIE) rb_bug("rb_gc_mark(): %p is T_ZOMBIE", (void *)obj);
-	rb_bug("rb_gc_mark(): unknown data type 0x%x(%p) %s",
-	       BUILTIN_TYPE(obj), (void *)any,
-	       is_pointer_to_heap(objspace, any) ? "corrupted object" : "non object");
+        if (BUILTIN_TYPE(obj) == T_NONE)   rb_bug("rb_gc_mark(): %p is T_NONE", (void *)obj);
+        if (BUILTIN_TYPE(obj) == T_ZOMBIE) rb_bug("rb_gc_mark(): %p is T_ZOMBIE", (void *)obj);
+        rb_bug("rb_gc_mark(): unknown data type 0x%x(%p) %s",
+               BUILTIN_TYPE(obj), (void *)any,
+               is_pointer_to_heap(objspace, any) ? "corrupted object" : "non object");
     }
 }
 
@@ -7133,39 +7443,39 @@ gc_mark_stacked_objects(rb_objspace_t *objspace, int incremental, size_t count)
 #endif
 
     while (pop_mark_stack(mstack, &obj)) {
-	if (obj == Qundef) continue; /* skip */
+        if (UNDEF_P(obj)) continue; /* skip */
 
-	if (RGENGC_CHECK_MODE && !RVALUE_MARKED(obj)) {
-	    rb_bug("gc_mark_stacked_objects: %s is not marked.", obj_info(obj));
-	}
+        if (RGENGC_CHECK_MODE && !RVALUE_MARKED(obj)) {
+            rb_bug("gc_mark_stacked_objects: %s is not marked.", obj_info(obj));
+        }
         gc_mark_children(objspace, obj);
 
 #if GC_ENABLE_INCREMENTAL_MARK
-	if (incremental) {
-	    if (RGENGC_CHECK_MODE && !RVALUE_MARKING(obj)) {
-		rb_bug("gc_mark_stacked_objects: incremental, but marking bit is 0");
-	    }
-	    CLEAR_IN_BITMAP(GET_HEAP_MARKING_BITS(obj), obj);
-	    popped_count++;
+        if (incremental) {
+            if (RGENGC_CHECK_MODE && !RVALUE_MARKING(obj)) {
+                rb_bug("gc_mark_stacked_objects: incremental, but marking bit is 0");
+            }
+            CLEAR_IN_BITMAP(GET_HEAP_MARKING_BITS(obj), obj);
+            popped_count++;
 
-	    if (popped_count + (objspace->marked_slots - marked_slots_at_the_beginning) > count) {
-		break;
-	    }
-	}
-	else {
-	    /* just ignore marking bits */
-	}
+            if (popped_count + (objspace->marked_slots - marked_slots_at_the_beginning) > count) {
+                break;
+            }
+        }
+        else {
+            /* just ignore marking bits */
+        }
 #endif
     }
 
     if (RGENGC_CHECK_MODE >= 3) gc_verify_internal_consistency(objspace);
 
     if (is_mark_stack_empty(mstack)) {
-	shrink_stack_chunk_cache(mstack);
-	return TRUE;
+        shrink_stack_chunk_cache(mstack);
+        return TRUE;
     }
     else {
-	return FALSE;
+        return FALSE;
     }
 }
 
@@ -7192,13 +7502,13 @@ show_mark_ticks(void)
     int i;
     fprintf(stderr, "mark ticks result:\n");
     for (i=0; i<MAX_TICKS; i++) {
-	const char *category = mark_ticks_categories[i];
-	if (category) {
-	    fprintf(stderr, "%s\t%8lu\n", category, (unsigned long)mark_ticks[i]);
-	}
-	else {
-	    break;
-	}
+        const char *category = mark_ticks_categories[i];
+        if (category) {
+            fprintf(stderr, "%s\t%8lu\n", category, (unsigned long)mark_ticks[i]);
+        }
+        else {
+            break;
+        }
     }
 }
 
@@ -7217,7 +7527,7 @@ gc_mark_roots(rb_objspace_t *objspace, const char **categoryp)
     const char *prev_category = 0;
 
     if (mark_ticks_categories[0] == 0) {
-	atexit(show_mark_ticks);
+        atexit(show_mark_ticks);
     }
 #endif
 
@@ -7228,10 +7538,10 @@ gc_mark_roots(rb_objspace_t *objspace, const char **categoryp)
 #if PRINT_ROOT_TICKS
 #define MARK_CHECKPOINT_PRINT_TICK(category) do { \
     if (prev_category) { \
-	tick_t t = tick(); \
-	mark_ticks[tick_count] = t - start_tick; \
-	mark_ticks_categories[tick_count] = prev_category; \
-	tick_count++; \
+        tick_t t = tick(); \
+        mark_ticks[tick_count] = t - start_tick; \
+        mark_ticks_categories[tick_count] = prev_category; \
+        tick_count++; \
     } \
     prev_category = category; \
     start_tick = tick(); \
@@ -7312,8 +7622,8 @@ static void
 reflist_add(struct reflist *refs, VALUE obj)
 {
     if (refs->pos == refs->size) {
-	refs->size *= 2;
-	SIZED_REALLOC_N(refs->list, VALUE, refs->size, refs->size/2);
+        refs->size *= 2;
+        SIZED_REALLOC_N(refs->list, VALUE, refs->size, refs->size/2);
     }
 
     refs->list[refs->pos++] = obj;
@@ -7324,14 +7634,14 @@ reflist_dump(struct reflist *refs)
 {
     int i;
     for (i=0; i<refs->pos; i++) {
-	VALUE obj = refs->list[i];
-	if (IS_ROOTSIG(obj)) { /* root */
-	    fprintf(stderr, "<root@%s>", GET_ROOTSIG(obj));
-	}
-	else {
-	    fprintf(stderr, "<%s>", obj_info(obj));
-	}
-	if (i+1 < refs->pos) fprintf(stderr, ", ");
+        VALUE obj = refs->list[i];
+        if (IS_ROOTSIG(obj)) { /* root */
+            fprintf(stderr, "<root@%s>", GET_ROOTSIG(obj));
+        }
+        else {
+            fprintf(stderr, "<%s>", obj_info(obj));
+        }
+        if (i+1 < refs->pos) fprintf(stderr, ", ");
     }
 }
 
@@ -7340,8 +7650,8 @@ reflist_referred_from_machine_context(struct reflist *refs)
 {
     int i;
     for (i=0; i<refs->pos; i++) {
-	VALUE obj = refs->list[i];
-	if (IS_ROOTSIG(obj) && strcmp(GET_ROOTSIG(obj), "machine_context") == 0) return 1;
+        VALUE obj = refs->list[i];
+        if (IS_ROOTSIG(obj) && strcmp(GET_ROOTSIG(obj), "machine_context") == 0) return 1;
     }
     return 0;
 }
@@ -7369,13 +7679,13 @@ allrefs_add(struct allrefs *data, VALUE obj)
 
     if (st_lookup(data->references, obj, &r)) {
         refs = (struct reflist *)r;
-	reflist_add(refs, data->root_obj);
-	return 0;
+        reflist_add(refs, data->root_obj);
+        return 0;
     }
     else {
-	refs = reflist_create(data->root_obj);
-	st_insert(data->references, obj, (st_data_t)refs);
-	return 1;
+        refs = reflist_create(data->root_obj);
+        st_insert(data->references, obj, (st_data_t)refs);
+        return 1;
     }
 }
 
@@ -7385,7 +7695,7 @@ allrefs_i(VALUE obj, void *ptr)
     struct allrefs *data = (struct allrefs *)ptr;
 
     if (allrefs_add(data, obj)) {
-	push_mark_stack(&data->mark_stack, obj);
+        push_mark_stack(&data->mark_stack, obj);
     }
 }
 
@@ -7397,7 +7707,7 @@ allrefs_roots_i(VALUE obj, void *ptr)
     data->root_obj = MAKE_ROOTSIG(data->category);
 
     if (allrefs_add(data, obj)) {
-	push_mark_stack(&data->mark_stack, obj);
+        push_mark_stack(&data->mark_stack, obj);
     }
 }
 #define PUSH_MARK_FUNC_DATA(v) do { \
@@ -7430,7 +7740,7 @@ objspace_allrefs(rb_objspace_t *objspace)
 
     /* traverse rest objects reachable from root objects */
     while (pop_mark_stack(&data.mark_stack, &obj)) {
-	rb_objspace_reachable_objects_from(data.root_obj = obj, allrefs_i, &data);
+        rb_objspace_reachable_objects_from(data.root_obj = obj, allrefs_i, &data);
     }
     free_stack_chunks(&data.mark_stack);
 
@@ -7483,18 +7793,18 @@ gc_check_after_marks_i(st_data_t k, st_data_t v, st_data_t ptr)
 
     /* object should be marked or oldgen */
     if (!MARKED_IN_BITMAP(GET_HEAP_MARK_BITS(obj), obj)) {
-	fprintf(stderr, "gc_check_after_marks_i: %s is not marked and not oldgen.\n", obj_info(obj));
-	fprintf(stderr, "gc_check_after_marks_i: %p is referred from ", (void *)obj);
-	reflist_dump(refs);
-
-	if (reflist_referred_from_machine_context(refs)) {
-	    fprintf(stderr, " (marked from machine stack).\n");
-	    /* marked from machine context can be false positive */
-	}
-	else {
-	    objspace->rgengc.error_count++;
-	    fprintf(stderr, "\n");
-	}
+        fprintf(stderr, "gc_check_after_marks_i: %s is not marked and not oldgen.\n", obj_info(obj));
+        fprintf(stderr, "gc_check_after_marks_i: %p is referred from ", (void *)obj);
+        reflist_dump(refs);
+
+        if (reflist_referred_from_machine_context(refs)) {
+            fprintf(stderr, " (marked from machine stack).\n");
+            /* marked from machine context can be false positive */
+        }
+        else {
+            objspace->rgengc.error_count++;
+            fprintf(stderr, "\n");
+        }
     }
     return ST_CONTINUE;
 }
@@ -7511,14 +7821,14 @@ gc_marks_check(rb_objspace_t *objspace, st_foreach_callback_func *checker_func,
     objspace->rgengc.allrefs_table = objspace_allrefs(objspace);
 
     if (checker_func) {
-	st_foreach(objspace->rgengc.allrefs_table, checker_func, (st_data_t)objspace);
+        st_foreach(objspace->rgengc.allrefs_table, checker_func, (st_data_t)objspace);
     }
 
     if (objspace->rgengc.error_count > 0) {
 #if RGENGC_CHECK_MODE >= 5
-	allrefs_dump(objspace);
+        allrefs_dump(objspace);
 #endif
-	if (checker_name) rb_bug("%s: GC has problem.", checker_name);
+        if (checker_name) rb_bug("%s: GC has problem.", checker_name);
     }
 
     objspace_allrefs_destruct(objspace->rgengc.allrefs_table);
@@ -7552,12 +7862,12 @@ check_generation_i(const VALUE child, void *ptr)
     if (RGENGC_CHECK_MODE) GC_ASSERT(RVALUE_OLD_P(parent));
 
     if (!RVALUE_OLD_P(child)) {
-	if (!RVALUE_REMEMBERED(parent) &&
-	    !RVALUE_REMEMBERED(child) &&
-	    !RVALUE_UNCOLLECTIBLE(child)) {
-	    fprintf(stderr, "verify_internal_consistency_reachable_i: WB miss (O->Y) %s -> %s\n", obj_info(parent), obj_info(child));
-	    data->err_count++;
-	}
+        if (!RVALUE_REMEMBERED(parent) &&
+            !RVALUE_REMEMBERED(child) &&
+            !RVALUE_UNCOLLECTIBLE(child)) {
+            fprintf(stderr, "verify_internal_consistency_reachable_i: WB miss (O->Y) %s -> %s\n", obj_info(parent), obj_info(child));
+            data->err_count++;
+        }
     }
 }
 
@@ -7568,9 +7878,9 @@ check_color_i(const VALUE child, void *ptr)
     const VALUE parent = data->parent;
 
     if (!RVALUE_WB_UNPROTECTED(parent) && RVALUE_WHITE_P(child)) {
-	fprintf(stderr, "verify_internal_consistency_reachable_i: WB miss (B->W) - %s -> %s\n",
-		obj_info(parent), obj_info(child));
-	data->err_count++;
+        fprintf(stderr, "verify_internal_consistency_reachable_i: WB miss (B->W) - %s -> %s\n",
+                obj_info(parent), obj_info(child));
+        data->err_count++;
     }
 }
 
@@ -7595,12 +7905,11 @@ verify_internal_consistency_i(void *page_start, void *page_end, size_t stride,
     rb_objspace_t *objspace = data->objspace;
 
     for (obj = (VALUE)page_start; obj != (VALUE)page_end; obj += stride) {
-        void *poisoned = asan_poisoned_object_p(obj);
-        asan_unpoison_object(obj, false);
+        void *poisoned = asan_unpoison_object_temporary(obj);
 
-	if (is_live_object(objspace, obj)) {
-	    /* count objects */
-	    data->live_object_count++;
+        if (is_live_object(objspace, obj)) {
+            /* count objects */
+            data->live_object_count++;
             data->parent = obj;
 
             /* Normally, we don't expect T_MOVED objects to be in the heap.
@@ -7610,30 +7919,30 @@ verify_internal_consistency_i(void *page_start, void *page_end, size_t stride,
                 rb_objspace_reachable_objects_from(obj, check_children_i, (void *)data);
             }
 
-	    /* check health of children */
-	    if (RVALUE_OLD_P(obj)) data->old_object_count++;
-	    if (RVALUE_WB_UNPROTECTED(obj) && RVALUE_UNCOLLECTIBLE(obj)) data->remembered_shady_count++;
-
-	    if (!is_marking(objspace) && RVALUE_OLD_P(obj)) {
-		/* reachable objects from an oldgen object should be old or (young with remember) */
-		data->parent = obj;
-		rb_objspace_reachable_objects_from(obj, check_generation_i, (void *)data);
-	    }
-
-	    if (is_incremental_marking(objspace)) {
-		if (RVALUE_BLACK_P(obj)) {
-		    /* reachable objects from black objects should be black or grey objects */
-		    data->parent = obj;
-		    rb_objspace_reachable_objects_from(obj, check_color_i, (void *)data);
-		}
-	    }
-	}
-	else {
-	    if (BUILTIN_TYPE(obj) == T_ZOMBIE) {
-		GC_ASSERT((RBASIC(obj)->flags & ~FL_SEEN_OBJ_ID) == T_ZOMBIE);
-		data->zombie_object_count++;
-	    }
-	}
+            /* check health of children */
+            if (RVALUE_OLD_P(obj)) data->old_object_count++;
+            if (RVALUE_WB_UNPROTECTED(obj) && RVALUE_UNCOLLECTIBLE(obj)) data->remembered_shady_count++;
+
+            if (!is_marking(objspace) && RVALUE_OLD_P(obj)) {
+                /* reachable objects from an oldgen object should be old or (young with remember) */
+                data->parent = obj;
+                rb_objspace_reachable_objects_from(obj, check_generation_i, (void *)data);
+            }
+
+            if (is_incremental_marking(objspace)) {
+                if (RVALUE_BLACK_P(obj)) {
+                    /* reachable objects from black objects should be black or grey objects */
+                    data->parent = obj;
+                    rb_objspace_reachable_objects_from(obj, check_color_i, (void *)data);
+                }
+            }
+        }
+        else {
+            if (BUILTIN_TYPE(obj) == T_ZOMBIE) {
+                GC_ASSERT((RBASIC(obj)->flags & ~FL_SEEN_OBJ_ID) == T_ZOMBIE);
+                data->zombie_object_count++;
+            }
+        }
         if (poisoned) {
             GC_ASSERT(BUILTIN_TYPE(obj) == T_NONE);
             asan_poison_object(obj);
@@ -7658,18 +7967,18 @@ gc_verify_heap_page(rb_objspace_t *objspace, struct heap_page *page, VALUE obj)
 
     for (uintptr_t ptr = start; ptr < end; ptr += slot_size) {
         VALUE val = (VALUE)ptr;
-        void *poisoned = asan_poisoned_object_p(val);
-        asan_unpoison_object(val, false);
-
-	if (RBASIC(val) == 0) free_objects++;
-	if (BUILTIN_TYPE(val) == T_ZOMBIE) zombie_objects++;
-	if (RVALUE_PAGE_UNCOLLECTIBLE(page, val) && RVALUE_PAGE_WB_UNPROTECTED(page, val)) {
-	    has_remembered_shady = TRUE;
-	}
-	if (RVALUE_PAGE_MARKING(page, val)) {
-	    has_remembered_old = TRUE;
-	    remembered_old_objects++;
-	}
+        void *poisoned = asan_unpoison_object_temporary(val);
+        enum ruby_value_type type = BUILTIN_TYPE(val);
+
+        if (type == T_NONE) free_objects++;
+        if (type == T_ZOMBIE) zombie_objects++;
+        if (RVALUE_PAGE_UNCOLLECTIBLE(page, val) && RVALUE_PAGE_WB_UNPROTECTED(page, val)) {
+            has_remembered_shady = TRUE;
+        }
+        if (RVALUE_PAGE_MARKING(page, val)) {
+            has_remembered_old = TRUE;
+            remembered_old_objects++;
+        }
 
         if (poisoned) {
             GC_ASSERT(BUILTIN_TYPE(val) == T_NONE);
@@ -7678,31 +7987,31 @@ gc_verify_heap_page(rb_objspace_t *objspace, struct heap_page *page, VALUE obj)
     }
 
     if (!is_incremental_marking(objspace) &&
-	page->flags.has_remembered_objects == FALSE && has_remembered_old == TRUE) {
+        page->flags.has_remembered_objects == FALSE && has_remembered_old == TRUE) {
 
         for (uintptr_t ptr = start; ptr < end; ptr += slot_size) {
             VALUE val = (VALUE)ptr;
-	    if (RVALUE_PAGE_MARKING(page, val)) {
-		fprintf(stderr, "marking -> %s\n", obj_info(val));
-	    }
-	}
-	rb_bug("page %p's has_remembered_objects should be false, but there are remembered old objects (%d). %s",
-	       (void *)page, remembered_old_objects, obj ? obj_info(obj) : "");
+            if (RVALUE_PAGE_MARKING(page, val)) {
+                fprintf(stderr, "marking -> %s\n", obj_info(val));
+            }
+        }
+        rb_bug("page %p's has_remembered_objects should be false, but there are remembered old objects (%d). %s",
+               (void *)page, remembered_old_objects, obj ? obj_info(obj) : "");
     }
 
     if (page->flags.has_uncollectible_shady_objects == FALSE && has_remembered_shady == TRUE) {
-	rb_bug("page %p's has_remembered_shady should be false, but there are remembered shady objects. %s",
-	       (void *)page, obj ? obj_info(obj) : "");
+        rb_bug("page %p's has_remembered_shady should be false, but there are remembered shady objects. %s",
+               (void *)page, obj ? obj_info(obj) : "");
     }
 
     if (0) {
-	/* free_slots may not equal to free_objects */
-	if (page->free_slots != free_objects) {
-	    rb_bug("page %p's free_slots should be %d, but %d\n", (void *)page, page->free_slots, free_objects);
-	}
+        /* free_slots may not equal to free_objects */
+        if (page->free_slots != free_objects) {
+            rb_bug("page %p's free_slots should be %d, but %d\n", (void *)page, page->free_slots, free_objects);
+        }
     }
     if (page->final_slots != zombie_objects) {
-	rb_bug("page %p's final_slots should be %d, but %d\n", (void *)page, page->final_slots, zombie_objects);
+        rb_bug("page %p's final_slots should be %d, but %d\n", (void *)page, page->final_slots, zombie_objects);
     }
 
     return remembered_old_objects;
@@ -7715,7 +8024,7 @@ gc_verify_heap_pages_(rb_objspace_t *objspace, struct ccan_list_head *head)
     struct heap_page *page = 0;
 
     ccan_list_for_each(head, page, page_node) {
-        asan_unpoison_memory_region(&page->freelist, sizeof(RVALUE*), false);
+        asan_unlock_freelist(page);
         RVALUE *p = page->freelist;
         while (p) {
             VALUE vp = (VALUE)p;
@@ -7727,11 +8036,11 @@ gc_verify_heap_pages_(rb_objspace_t *objspace, struct ccan_list_head *head)
             p = p->as.free.next;
             asan_poison_object(prev);
         }
-        asan_poison_memory_region(&page->freelist, sizeof(RVALUE*));
+        asan_lock_freelist(page);
 
-	if (page->flags.has_remembered_objects == FALSE) {
-	    remembered_old_objects += gc_verify_heap_page(objspace, page, Qfalse);
-	}
+        if (page->flags.has_remembered_objects == FALSE) {
+            remembered_old_objects += gc_verify_heap_page(objspace, page, Qfalse);
+        }
     }
 
     return remembered_old_objects;
@@ -7786,11 +8095,11 @@ gc_verify_internal_consistency_(rb_objspace_t *objspace)
 
     if (data.err_count != 0) {
 #if RGENGC_CHECK_MODE >= 5
-	objspace->rgengc.error_count = data.err_count;
-	gc_marks_check(objspace, NULL, NULL);
-	allrefs_dump(objspace);
+        objspace->rgengc.error_count = data.err_count;
+        gc_marks_check(objspace, NULL, NULL);
+        allrefs_dump(objspace);
 #endif
-	rb_bug("gc_verify_internal_consistency: found internal inconsistency.");
+        rb_bug("gc_verify_internal_consistency: found internal inconsistency.");
     }
 
     /* check heap_page status */
@@ -7801,39 +8110,39 @@ gc_verify_internal_consistency_(rb_objspace_t *objspace)
     if (!is_lazy_sweeping(objspace) &&
         !finalizing &&
         ruby_single_main_ractor != NULL) {
-	if (objspace_live_slots(objspace) != data.live_object_count) {
-	    fprintf(stderr, "heap_pages_final_slots: %"PRIdSIZE", "
+        if (objspace_live_slots(objspace) != data.live_object_count) {
+            fprintf(stderr, "heap_pages_final_slots: %"PRIdSIZE", "
                     "objspace->profile.total_freed_objects: %"PRIdSIZE"\n",
-		    heap_pages_final_slots, objspace->profile.total_freed_objects);
-	    rb_bug("inconsistent live slot number: expect %"PRIuSIZE", but %"PRIuSIZE".",
+                    heap_pages_final_slots, objspace->profile.total_freed_objects);
+            rb_bug("inconsistent live slot number: expect %"PRIuSIZE", but %"PRIuSIZE".",
                    objspace_live_slots(objspace), data.live_object_count);
-	}
+        }
     }
 
     if (!is_marking(objspace)) {
-	if (objspace->rgengc.old_objects != data.old_object_count) {
-	    rb_bug("inconsistent old slot number: expect %"PRIuSIZE", but %"PRIuSIZE".",
+        if (objspace->rgengc.old_objects != data.old_object_count) {
+            rb_bug("inconsistent old slot number: expect %"PRIuSIZE", but %"PRIuSIZE".",
                    objspace->rgengc.old_objects, data.old_object_count);
-	}
-	if (objspace->rgengc.uncollectible_wb_unprotected_objects != data.remembered_shady_count) {
+        }
+        if (objspace->rgengc.uncollectible_wb_unprotected_objects != data.remembered_shady_count) {
             rb_bug("inconsistent number of wb unprotected objects: expect %"PRIuSIZE", but %"PRIuSIZE".",
                    objspace->rgengc.uncollectible_wb_unprotected_objects, data.remembered_shady_count);
-	}
+        }
     }
 
     if (!finalizing) {
-	size_t list_count = 0;
+        size_t list_count = 0;
 
-	{
-	    VALUE z = heap_pages_deferred_final;
-	    while (z) {
-		list_count++;
-		z = RZOMBIE(z)->next;
-	    }
-	}
+        {
+            VALUE z = heap_pages_deferred_final;
+            while (z) {
+                list_count++;
+                z = RZOMBIE(z)->next;
+            }
+        }
 
-	if (heap_pages_final_slots != data.zombie_object_count ||
-	    heap_pages_final_slots != list_count) {
+        if (heap_pages_final_slots != data.zombie_object_count ||
+            heap_pages_final_slots != list_count) {
 
             rb_bug("inconsistent finalizing object count:\n"
                     "  expect %"PRIuSIZE"\n"
@@ -7842,7 +8151,7 @@ gc_verify_internal_consistency_(rb_objspace_t *objspace)
                     heap_pages_final_slots,
                     data.zombie_object_count,
                     list_count);
-	}
+        }
     }
 
     gc_report(5, objspace, "gc_verify_internal_consistency: OK\n");
@@ -7913,20 +8222,20 @@ gc_marks_start(rb_objspace_t *objspace, int full_mark)
         size_t incremental_marking_steps = (objspace->rincgc.pooled_slots / INCREMENTAL_MARK_STEP_ALLOCATIONS) + 1;
         objspace->rincgc.step_slots = (objspace->marked_slots * 2) / incremental_marking_steps;
 
-	if (0) fprintf(stderr, "objspace->marked_slots: %"PRIdSIZE", "
+        if (0) fprintf(stderr, "objspace->marked_slots: %"PRIdSIZE", "
                        "objspace->rincgc.pooled_page_num: %"PRIdSIZE", "
                        "objspace->rincgc.step_slots: %"PRIdSIZE", \n",
                        objspace->marked_slots, objspace->rincgc.pooled_slots, objspace->rincgc.step_slots);
 #endif
-	objspace->flags.during_minor_gc = FALSE;
+        objspace->flags.during_minor_gc = FALSE;
         if (ruby_enable_autocompact) {
             objspace->flags.during_compacting |= TRUE;
         }
-	objspace->profile.major_gc_count++;
-	objspace->rgengc.uncollectible_wb_unprotected_objects = 0;
-	objspace->rgengc.old_objects = 0;
-	objspace->rgengc.last_major_gc = objspace->profile.count;
-	objspace->marked_slots = 0;
+        objspace->profile.major_gc_count++;
+        objspace->rgengc.uncollectible_wb_unprotected_objects = 0;
+        objspace->rgengc.old_objects = 0;
+        objspace->rgengc.last_major_gc = objspace->profile.count;
+        objspace->marked_slots = 0;
 
         for (int i = 0; i < SIZE_POOL_COUNT; i++) {
             rb_size_pool_t *size_pool = &size_pools[i];
@@ -7936,10 +8245,10 @@ gc_marks_start(rb_objspace_t *objspace, int full_mark)
         }
     }
     else {
-	objspace->flags.during_minor_gc = TRUE;
-	objspace->marked_slots =
-	  objspace->rgengc.old_objects + objspace->rgengc.uncollectible_wb_unprotected_objects; /* uncollectible objects are marked already */
-	objspace->profile.minor_gc_count++;
+        objspace->flags.during_minor_gc = TRUE;
+        objspace->marked_slots =
+          objspace->rgengc.old_objects + objspace->rgengc.uncollectible_wb_unprotected_objects; /* uncollectible objects are marked already */
+        objspace->profile.minor_gc_count++;
 
         for (int i = 0; i < SIZE_POOL_COUNT; i++) {
             rgengc_rememberset_mark(objspace, SIZE_POOL_EDEN_HEAP(&size_pools[i]));
@@ -7976,22 +8285,22 @@ gc_marks_wb_unprotected_objects(rb_objspace_t *objspace, rb_heap_t *heap)
     struct heap_page *page = 0;
 
     ccan_list_for_each(&heap->pages, page, page_node) {
-	bits_t *mark_bits = page->mark_bits;
-	bits_t *wbun_bits = page->wb_unprotected_bits;
+        bits_t *mark_bits = page->mark_bits;
+        bits_t *wbun_bits = page->wb_unprotected_bits;
         uintptr_t p = page->start;
-	size_t j;
+        size_t j;
 
         bits_t bits = mark_bits[0] & wbun_bits[0];
         bits >>= NUM_IN_PAGE(p);
         gc_marks_wb_unprotected_objects_plane(objspace, p, bits);
         p += (BITS_BITLENGTH - NUM_IN_PAGE(p)) * BASE_SLOT_SIZE;
 
-	for (j=1; j<HEAP_PAGE_BITMAP_LIMIT; j++) {
-	    bits_t bits = mark_bits[j] & wbun_bits[j];
+        for (j=1; j<HEAP_PAGE_BITMAP_LIMIT; j++) {
+            bits_t bits = mark_bits[j] & wbun_bits[j];
 
             gc_marks_wb_unprotected_objects_plane(objspace, p, bits);
             p += BITS_BITLENGTH * BASE_SLOT_SIZE;
-	}
+        }
     }
 
     gc_mark_stacked_objects_all(objspace);
@@ -8004,22 +8313,22 @@ gc_marks_finish(rb_objspace_t *objspace)
 #if GC_ENABLE_INCREMENTAL_MARK
     /* finish incremental GC */
     if (is_incremental_marking(objspace)) {
-	if (RGENGC_CHECK_MODE && is_mark_stack_empty(&objspace->mark_stack) == 0) {
-	    rb_bug("gc_marks_finish: mark stack is not empty (%"PRIdSIZE").",
+        if (RGENGC_CHECK_MODE && is_mark_stack_empty(&objspace->mark_stack) == 0) {
+            rb_bug("gc_marks_finish: mark stack is not empty (%"PRIdSIZE").",
                    mark_stack_size(&objspace->mark_stack));
-	}
+        }
 
-	gc_mark_roots(objspace, 0);
+        gc_mark_roots(objspace, 0);
         while (gc_mark_stacked_objects_incremental(objspace, INT_MAX) == false);
 
 #if RGENGC_CHECK_MODE >= 2
-	if (gc_verify_heap_pages(objspace) != 0) {
-	    rb_bug("gc_marks_finish (incremental): there are remembered old objects.");
-	}
+        if (gc_verify_heap_pages(objspace) != 0) {
+            rb_bug("gc_marks_finish (incremental): there are remembered old objects.");
+        }
 #endif
 
-	objspace->flags.during_incremental_marking = FALSE;
-	/* check children of all marked wb-unprotected objects */
+        objspace->flags.during_incremental_marking = FALSE;
+        /* check children of all marked wb-unprotected objects */
         for (int i = 0; i < SIZE_POOL_COUNT; i++) {
             gc_marks_wb_unprotected_objects(objspace, SIZE_POOL_EDEN_HEAP(&size_pools[i]));
         }
@@ -8031,10 +8340,10 @@ gc_marks_finish(rb_objspace_t *objspace)
 #endif
 
     if (is_full_marking(objspace)) {
-	/* See the comment about RUBY_GC_HEAP_OLDOBJECT_LIMIT_FACTOR */
-	const double r = gc_params.oldobject_limit_factor;
-	objspace->rgengc.uncollectible_wb_unprotected_objects_limit = (size_t)(objspace->rgengc.uncollectible_wb_unprotected_objects * r);
-	objspace->rgengc.old_objects_limit = (size_t)(objspace->rgengc.old_objects * r);
+        /* See the comment about RUBY_GC_HEAP_OLDOBJECT_LIMIT_FACTOR */
+        const double r = gc_params.oldobject_limit_factor;
+        objspace->rgengc.uncollectible_wb_unprotected_objects_limit = (size_t)(objspace->rgengc.uncollectible_wb_unprotected_objects * r);
+        objspace->rgengc.old_objects_limit = (size_t)(objspace->rgengc.old_objects * r);
     }
 
 #if RGENGC_CHECK_MODE >= 4
@@ -8044,81 +8353,81 @@ gc_marks_finish(rb_objspace_t *objspace)
 #endif
 
     {
-	/* decide full GC is needed or not */
+        /* decide full GC is needed or not */
         size_t total_slots = heap_allocatable_slots(objspace) + heap_eden_total_slots(objspace);
-	size_t sweep_slots = total_slots - objspace->marked_slots; /* will be swept slots */
-	size_t max_free_slots = (size_t)(total_slots * gc_params.heap_free_slots_max_ratio);
-	size_t min_free_slots = (size_t)(total_slots * gc_params.heap_free_slots_min_ratio);
-	int full_marking = is_full_marking(objspace);
+        size_t sweep_slots = total_slots - objspace->marked_slots; /* will be swept slots */
+        size_t max_free_slots = (size_t)(total_slots * gc_params.heap_free_slots_max_ratio);
+        size_t min_free_slots = (size_t)(total_slots * gc_params.heap_free_slots_min_ratio);
+        int full_marking = is_full_marking(objspace);
         const int r_cnt = GET_VM()->ractor.cnt;
         const int r_mul = r_cnt > 8 ? 8 : r_cnt; // upto 8
 
         GC_ASSERT(heap_eden_total_slots(objspace) >= objspace->marked_slots);
 
-	/* setup free-able page counts */
+        /* setup free-able page counts */
         if (max_free_slots < gc_params.heap_init_slots * r_mul) {
             max_free_slots = gc_params.heap_init_slots * r_mul;
         }
 
-	if (sweep_slots > max_free_slots) {
-	    heap_pages_freeable_pages = (sweep_slots - max_free_slots) / HEAP_PAGE_OBJ_LIMIT;
-	}
-	else {
-	    heap_pages_freeable_pages = 0;
-	}
+        if (sweep_slots > max_free_slots) {
+            heap_pages_freeable_pages = (sweep_slots - max_free_slots) / HEAP_PAGE_OBJ_LIMIT;
+        }
+        else {
+            heap_pages_freeable_pages = 0;
+        }
 
         /* check free_min */
         if (min_free_slots < gc_params.heap_free_slots * r_mul) {
             min_free_slots = gc_params.heap_free_slots * r_mul;
         }
 
-	if (sweep_slots < min_free_slots) {
-	    if (!full_marking) {
-		if (objspace->profile.count - objspace->rgengc.last_major_gc < RVALUE_OLD_AGE) {
-		    full_marking = TRUE;
-		    /* do not update last_major_gc, because full marking is not done. */
+        if (sweep_slots < min_free_slots) {
+            if (!full_marking) {
+                if (objspace->profile.count - objspace->rgengc.last_major_gc < RVALUE_OLD_AGE) {
+                    full_marking = TRUE;
+                    /* do not update last_major_gc, because full marking is not done. */
                     /* goto increment; */
-		}
-		else {
-		    gc_report(1, objspace, "gc_marks_finish: next is full GC!!)\n");
-		    objspace->rgengc.need_major_gc |= GPR_FLAG_MAJOR_BY_NOFREE;
-		}
-	    }
+                }
+                else {
+                    gc_report(1, objspace, "gc_marks_finish: next is full GC!!)\n");
+                    objspace->rgengc.need_major_gc |= GPR_FLAG_MAJOR_BY_NOFREE;
+                }
+            }
 
 #if !USE_RVARGC
             if (full_marking) {
               /* increment: */
-		gc_report(1, objspace, "gc_marks_finish: heap_set_increment!!\n");
+                gc_report(1, objspace, "gc_marks_finish: heap_set_increment!!\n");
                 rb_size_pool_t *size_pool = &size_pools[0];
-                size_pool_allocatable_pages_set(objspace, size_pool, heap_extend_pages(objspace, sweep_slots, total_slots, heap_allocated_pages + heap_allocatable_pages(objspace)));
+                size_pool_allocatable_pages_set(objspace, size_pool, heap_extend_pages(objspace, size_pool, sweep_slots, total_slots, heap_allocated_pages + heap_allocatable_pages(objspace)));
 
                 heap_increment(objspace, size_pool, SIZE_POOL_EDEN_HEAP(size_pool));
-	    }
-#endif
-	}
-
-	if (full_marking) {
-	    /* See the comment about RUBY_GC_HEAP_OLDOBJECT_LIMIT_FACTOR */
-	    const double r = gc_params.oldobject_limit_factor;
-	    objspace->rgengc.uncollectible_wb_unprotected_objects_limit = (size_t)(objspace->rgengc.uncollectible_wb_unprotected_objects * r);
-	    objspace->rgengc.old_objects_limit = (size_t)(objspace->rgengc.old_objects * r);
-	}
-
-	if (objspace->rgengc.uncollectible_wb_unprotected_objects > objspace->rgengc.uncollectible_wb_unprotected_objects_limit) {
-	    objspace->rgengc.need_major_gc |= GPR_FLAG_MAJOR_BY_SHADY;
-	}
-	if (objspace->rgengc.old_objects > objspace->rgengc.old_objects_limit) {
-	    objspace->rgengc.need_major_gc |= GPR_FLAG_MAJOR_BY_OLDGEN;
-	}
-	if (RGENGC_FORCE_MAJOR_GC) {
-	    objspace->rgengc.need_major_gc = GPR_FLAG_MAJOR_BY_FORCE;
-	}
-
-	gc_report(1, objspace, "gc_marks_finish (marks %"PRIdSIZE" objects, "
+            }
+#endif
+        }
+
+        if (full_marking) {
+            /* See the comment about RUBY_GC_HEAP_OLDOBJECT_LIMIT_FACTOR */
+            const double r = gc_params.oldobject_limit_factor;
+            objspace->rgengc.uncollectible_wb_unprotected_objects_limit = (size_t)(objspace->rgengc.uncollectible_wb_unprotected_objects * r);
+            objspace->rgengc.old_objects_limit = (size_t)(objspace->rgengc.old_objects * r);
+        }
+
+        if (objspace->rgengc.uncollectible_wb_unprotected_objects > objspace->rgengc.uncollectible_wb_unprotected_objects_limit) {
+            objspace->rgengc.need_major_gc |= GPR_FLAG_MAJOR_BY_SHADY;
+        }
+        if (objspace->rgengc.old_objects > objspace->rgengc.old_objects_limit) {
+            objspace->rgengc.need_major_gc |= GPR_FLAG_MAJOR_BY_OLDGEN;
+        }
+        if (RGENGC_FORCE_MAJOR_GC) {
+            objspace->rgengc.need_major_gc = GPR_FLAG_MAJOR_BY_FORCE;
+        }
+
+        gc_report(1, objspace, "gc_marks_finish (marks %"PRIdSIZE" objects, "
                   "old %"PRIdSIZE" objects, total %"PRIdSIZE" slots, "
                   "sweep %"PRIdSIZE" slots, increment: %"PRIdSIZE", next GC: %s)\n",
                   objspace->marked_slots, objspace->rgengc.old_objects, heap_eden_total_slots(objspace), sweep_slots, heap_allocatable_pages(objspace),
-		  objspace->rgengc.need_major_gc ? "major" : "minor");
+                  objspace->rgengc.need_major_gc ? "major" : "minor");
     }
 
     rb_transient_heap_finish_marking();
@@ -8147,15 +8456,68 @@ gc_compact_heap_cursors_met_p(rb_heap_t *heap)
     return heap->sweeping_page == heap->compact_cursor;
 }
 
+static rb_size_pool_t *
+gc_compact_destination_pool(rb_objspace_t *objspace, rb_size_pool_t *src_pool, VALUE src)
+{
+    size_t obj_size;
+    size_t idx = 0;
+
+    switch (BUILTIN_TYPE(src)) {
+      case T_ARRAY:
+        obj_size = rb_ary_size_as_embedded(src);
+        break;
+
+      case T_OBJECT:
+        if (rb_shape_obj_too_complex(src)) {
+            return &size_pools[0];
+        }
+        else {
+            obj_size = rb_obj_embedded_size(ROBJECT_IV_CAPACITY(src));
+        }
+        break;
+
+      case T_STRING:
+        obj_size = rb_str_size_as_embedded(src);
+        break;
+
+      default:
+        return src_pool;
+    }
+
+    if (rb_gc_size_allocatable_p(obj_size)){
+        idx = size_pool_idx_for_size(obj_size);
+    }
+    return &size_pools[idx];
+}
+
 static bool
-gc_compact_move(rb_objspace_t *objspace, rb_heap_t *heap, VALUE src)
+gc_compact_move(rb_objspace_t *objspace, rb_heap_t *heap, rb_size_pool_t *size_pool, VALUE src)
 {
     GC_ASSERT(BUILTIN_TYPE(src) != T_MOVED);
-    rb_heap_t *dheap = heap;
+    GC_ASSERT(gc_is_moveable_obj(objspace, src));
+
+    rb_size_pool_t *dest_pool = gc_compact_destination_pool(objspace, size_pool, src);
+    rb_heap_t *dheap = SIZE_POOL_EDEN_HEAP(dest_pool);
+    rb_shape_t *new_shape = NULL;
+    rb_shape_t *orig_shape = NULL;
 
     if (gc_compact_heap_cursors_met_p(dheap)) {
-        return false;
+        return dheap != heap;
+    }
+
+    if (RB_TYPE_P(src, T_OBJECT)) {
+        orig_shape = rb_shape_get_shape(src);
+        if (dheap != heap && !rb_shape_obj_too_complex(src)) {
+            rb_shape_t *initial_shape = rb_shape_get_shape_by_id((shape_id_t)((dest_pool - size_pools) + SIZE_POOL_COUNT));
+            new_shape = rb_shape_traverse_from_new_root(initial_shape, orig_shape);
+
+            if (!new_shape) {
+                dest_pool = size_pool;
+                dheap = heap;
+            }
+        }
     }
+
     while (!try_move(objspace, dheap, dheap->free_pages, src)) {
         struct gc_sweep_context ctx = {
             .page = dheap->sweeping_page,
@@ -8163,21 +8525,38 @@ gc_compact_move(rb_objspace_t *objspace, rb_heap_t *heap, VALUE src)
             .freed_slots = 0,
             .empty_slots = 0,
         };
-        gc_sweep_page(objspace, heap, &ctx);
+
+        /* The page of src could be partially compacted, so it may contain
+         * T_MOVED. Sweeping a page may read objects on this page, so we
+         * need to lock the page. */
+        lock_page_body(objspace, GET_PAGE_BODY(src));
+        gc_sweep_page(objspace, dheap, &ctx);
+        unlock_page_body(objspace, GET_PAGE_BODY(src));
+
         if (dheap->sweeping_page->free_slots > 0) {
             heap_add_freepage(dheap, dheap->sweeping_page);
         };
 
         dheap->sweeping_page = ccan_list_next(&dheap->pages, dheap->sweeping_page, page_node);
         if (gc_compact_heap_cursors_met_p(dheap)) {
-            return false;
+            return dheap != heap;
+        }
+    }
+
+    if (orig_shape) {
+        if (new_shape) {
+            VALUE dest = rb_gc_location(src);
+            rb_shape_set_shape(dest, new_shape);
         }
+        RMOVED(src)->original_shape_id = rb_shape_id(orig_shape);
     }
+
     return true;
 }
 
 static bool
-gc_compact_plane(rb_objspace_t *objspace, rb_heap_t *heap, uintptr_t p, bits_t bitset, struct heap_page *page) {
+gc_compact_plane(rb_objspace_t *objspace, rb_size_pool_t *size_pool, rb_heap_t *heap, uintptr_t p, bits_t bitset, struct heap_page *page)
+{
     short slot_size = page->slot_size;
     short slot_bits = slot_size / BASE_SLOT_SIZE;
     GC_ASSERT(slot_bits > 0);
@@ -8189,9 +8568,11 @@ gc_compact_plane(rb_objspace_t *objspace, rb_heap_t *heap, uintptr_t p, bits_t b
         if (bitset & 1) {
             objspace->rcompactor.considered_count_table[BUILTIN_TYPE(vp)]++;
 
-            if (!gc_compact_move(objspace, heap, vp)) {
-                //the cursors met. bubble up
-                return false;
+            if (gc_is_moveable_obj(objspace, vp)) {
+                if (!gc_compact_move(objspace, heap, size_pool, vp)) {
+                    //the cursors met. bubble up
+                    return false;
+                }
             }
         }
         p += slot_size;
@@ -8218,7 +8599,7 @@ gc_compact_page(rb_objspace_t *objspace, rb_size_pool_t *size_pool, rb_heap_t *h
     bitset = (mark_bits[0] & ~pin_bits[0]);
     bitset >>= NUM_IN_PAGE(p);
     if (bitset) {
-        if (!gc_compact_plane(objspace, heap, (uintptr_t)p, bitset, page))
+        if (!gc_compact_plane(objspace, size_pool, heap, (uintptr_t)p, bitset, page))
             return false;
     }
     p += (BITS_BITLENGTH - NUM_IN_PAGE(p)) * BASE_SLOT_SIZE;
@@ -8226,7 +8607,7 @@ gc_compact_page(rb_objspace_t *objspace, rb_size_pool_t *size_pool, rb_heap_t *h
     for (int j = 1; j < HEAP_PAGE_BITMAP_LIMIT; j++) {
         bitset = (mark_bits[j] & ~pin_bits[j]);
         if (bitset) {
-            if (!gc_compact_plane(objspace, heap, (uintptr_t)p, bitset, page))
+            if (!gc_compact_plane(objspace, size_pool, heap, (uintptr_t)p, bitset, page))
                 return false;
         }
         p += BITS_BITLENGTH * BASE_SLOT_SIZE;
@@ -8236,7 +8617,8 @@ gc_compact_page(rb_objspace_t *objspace, rb_size_pool_t *size_pool, rb_heap_t *h
 }
 
 static bool
-gc_compact_all_compacted_p(rb_objspace_t *objspace) {
+gc_compact_all_compacted_p(rb_objspace_t *objspace)
+{
     for (int i = 0; i < SIZE_POOL_COUNT; i++) {
         rb_size_pool_t *size_pool = &size_pools[i];
         rb_heap_t *heap = SIZE_POOL_EDEN_HEAP(size_pool);
@@ -8270,7 +8652,6 @@ gc_sweep_compact(rb_objspace_t *objspace)
             struct heap_page *start_page = heap->compact_cursor;
 
             if (!gc_compact_page(objspace, size_pool, heap, start_page)) {
-                GC_ASSERT(heap->sweeping_page == heap->compact_cursor);
                 lock_page_body(objspace, GET_PAGE_BODY(start_page->start));
 
                 continue;
@@ -8305,7 +8686,7 @@ gc_marks_rest(rb_objspace_t *objspace)
         while (gc_mark_stacked_objects_incremental(objspace, INT_MAX) == FALSE);
     }
     else {
-	gc_mark_stacked_objects_all(objspace);
+        gc_mark_stacked_objects_all(objspace);
     }
 
     gc_marks_finish(objspace);
@@ -8364,29 +8745,29 @@ static void
 gc_report_body(int level, rb_objspace_t *objspace, const char *fmt, ...)
 {
     if (level <= RGENGC_DEBUG) {
-	char buf[1024];
-	FILE *out = stderr;
-	va_list args;
-	const char *status = " ";
+        char buf[1024];
+        FILE *out = stderr;
+        va_list args;
+        const char *status = " ";
 
-	if (during_gc) {
-	    status = is_full_marking(objspace) ? "+" : "-";
-	}
-	else {
-	    if (is_lazy_sweeping(objspace)) {
-		status = "S";
-	    }
-	    if (is_incremental_marking(objspace)) {
-		status = "M";
-	    }
-	}
+        if (during_gc) {
+            status = is_full_marking(objspace) ? "+" : "-";
+        }
+        else {
+            if (is_lazy_sweeping(objspace)) {
+                status = "S";
+            }
+            if (is_incremental_marking(objspace)) {
+                status = "M";
+            }
+        }
 
-	va_start(args, fmt);
-	vsnprintf(buf, 1024, fmt, args);
-	va_end(args);
+        va_start(args, fmt);
+        vsnprintf(buf, 1024, fmt, args);
+        va_end(args);
 
-	fprintf(out, "%s|", status);
-	fputs(buf, out);
+        fprintf(out, "%s|", status);
+        fputs(buf, out);
     }
 }
 
@@ -8407,12 +8788,12 @@ rgengc_remembersetbits_set(rb_objspace_t *objspace, VALUE obj)
     GC_ASSERT(!is_incremental_marking(objspace));
 
     if (MARKED_IN_BITMAP(bits, obj)) {
-	return FALSE;
+        return FALSE;
     }
     else {
-	page->flags.has_remembered_objects = TRUE;
-	MARK_IN_BITMAP(bits, obj);
-	return TRUE;
+        page->flags.has_remembered_objects = TRUE;
+        MARK_IN_BITMAP(bits, obj);
+        return TRUE;
     }
 }
 
@@ -8423,22 +8804,22 @@ static int
 rgengc_remember(rb_objspace_t *objspace, VALUE obj)
 {
     gc_report(6, objspace, "rgengc_remember: %s %s\n", obj_info(obj),
-	      rgengc_remembersetbits_get(objspace, obj) ? "was already remembered" : "is remembered now");
+              rgengc_remembersetbits_get(objspace, obj) ? "was already remembered" : "is remembered now");
 
     check_rvalue_consistency(obj);
 
     if (RGENGC_CHECK_MODE) {
-	if (RVALUE_WB_UNPROTECTED(obj)) rb_bug("rgengc_remember: %s is not wb protected.", obj_info(obj));
+        if (RVALUE_WB_UNPROTECTED(obj)) rb_bug("rgengc_remember: %s is not wb protected.", obj_info(obj));
     }
 
 #if RGENGC_PROFILE > 0
     if (!rgengc_remembered(objspace, obj)) {
-	if (RVALUE_WB_UNPROTECTED(obj) == 0) {
-	    objspace->profile.total_remembered_normal_object_count++;
+        if (RVALUE_WB_UNPROTECTED(obj) == 0) {
+            objspace->profile.total_remembered_normal_object_count++;
 #if RGENGC_PROFILE >= 2
-	    objspace->profile.remembered_normal_object_count_types[BUILTIN_TYPE(obj)]++;
+            objspace->profile.remembered_normal_object_count_types[BUILTIN_TYPE(obj)]++;
 #endif
-	}
+        }
     }
 #endif /* RGENGC_PROFILE > 0 */
 
@@ -8494,38 +8875,38 @@ rgengc_rememberset_mark(rb_objspace_t *objspace, rb_heap_t *heap)
     gc_report(1, objspace, "rgengc_rememberset_mark: start\n");
 
     ccan_list_for_each(&heap->pages, page, page_node) {
-	if (page->flags.has_remembered_objects | page->flags.has_uncollectible_shady_objects) {
+        if (page->flags.has_remembered_objects | page->flags.has_uncollectible_shady_objects) {
             uintptr_t p = page->start;
-	    bits_t bitset, bits[HEAP_PAGE_BITMAP_LIMIT];
-	    bits_t *marking_bits = page->marking_bits;
-	    bits_t *uncollectible_bits = page->uncollectible_bits;
-	    bits_t *wb_unprotected_bits = page->wb_unprotected_bits;
+            bits_t bitset, bits[HEAP_PAGE_BITMAP_LIMIT];
+            bits_t *marking_bits = page->marking_bits;
+            bits_t *uncollectible_bits = page->uncollectible_bits;
+            bits_t *wb_unprotected_bits = page->wb_unprotected_bits;
 #if PROFILE_REMEMBERSET_MARK
-	    if (page->flags.has_remembered_objects && page->flags.has_uncollectible_shady_objects) has_both++;
-	    else if (page->flags.has_remembered_objects) has_old++;
-	    else if (page->flags.has_uncollectible_shady_objects) has_shady++;
+            if (page->flags.has_remembered_objects && page->flags.has_uncollectible_shady_objects) has_both++;
+            else if (page->flags.has_remembered_objects) has_old++;
+            else if (page->flags.has_uncollectible_shady_objects) has_shady++;
 #endif
-	    for (j=0; j<HEAP_PAGE_BITMAP_LIMIT; j++) {
-		bits[j] = marking_bits[j] | (uncollectible_bits[j] & wb_unprotected_bits[j]);
-		marking_bits[j] = 0;
-	    }
-	    page->flags.has_remembered_objects = FALSE;
+            for (j=0; j<HEAP_PAGE_BITMAP_LIMIT; j++) {
+                bits[j] = marking_bits[j] | (uncollectible_bits[j] & wb_unprotected_bits[j]);
+                marking_bits[j] = 0;
+            }
+            page->flags.has_remembered_objects = FALSE;
 
             bitset = bits[0];
             bitset >>= NUM_IN_PAGE(p);
             rgengc_rememberset_mark_plane(objspace, p, bitset);
             p += (BITS_BITLENGTH - NUM_IN_PAGE(p)) * BASE_SLOT_SIZE;
 
-	    for (j=1; j < HEAP_PAGE_BITMAP_LIMIT; j++) {
-		bitset = bits[j];
+            for (j=1; j < HEAP_PAGE_BITMAP_LIMIT; j++) {
+                bitset = bits[j];
                 rgengc_rememberset_mark_plane(objspace, p, bitset);
                 p += BITS_BITLENGTH * BASE_SLOT_SIZE;
-	    }
-	}
+            }
+        }
 #if PROFILE_REMEMBERSET_MARK
-	else {
-	    skip++;
-	}
+        else {
+            skip++;
+        }
 #endif
     }
 
@@ -8541,12 +8922,12 @@ rgengc_mark_and_rememberset_clear(rb_objspace_t *objspace, rb_heap_t *heap)
     struct heap_page *page = 0;
 
     ccan_list_for_each(&heap->pages, page, page_node) {
-	memset(&page->mark_bits[0],       0, HEAP_PAGE_BITMAP_SIZE);
-	memset(&page->uncollectible_bits[0], 0, HEAP_PAGE_BITMAP_SIZE);
+        memset(&page->mark_bits[0],       0, HEAP_PAGE_BITMAP_SIZE);
+        memset(&page->uncollectible_bits[0], 0, HEAP_PAGE_BITMAP_SIZE);
         memset(&page->marking_bits[0],    0, HEAP_PAGE_BITMAP_SIZE);
         memset(&page->pinned_bits[0],     0, HEAP_PAGE_BITMAP_SIZE);
-	page->flags.has_uncollectible_shady_objects = FALSE;
-	page->flags.has_remembered_objects = FALSE;
+        page->flags.has_uncollectible_shady_objects = FALSE;
+        page->flags.has_remembered_objects = FALSE;
     }
 }
 
@@ -8558,9 +8939,9 @@ static void
 gc_writebarrier_generational(VALUE a, VALUE b, rb_objspace_t *objspace)
 {
     if (RGENGC_CHECK_MODE) {
-	if (!RVALUE_OLD_P(a)) rb_bug("gc_writebarrier_generational: %s is not an old object.", obj_info(a));
-	if ( RVALUE_OLD_P(b)) rb_bug("gc_writebarrier_generational: %s is an old object.", obj_info(b));
-	if (is_incremental_marking(objspace)) rb_bug("gc_writebarrier_generational: called while incremental marking: %s -> %s", obj_info(a), obj_info(b));
+        if (!RVALUE_OLD_P(a)) rb_bug("gc_writebarrier_generational: %s is not an old object.", obj_info(a));
+        if ( RVALUE_OLD_P(b)) rb_bug("gc_writebarrier_generational: %s is an old object.", obj_info(b));
+        if (is_incremental_marking(objspace)) rb_bug("gc_writebarrier_generational: called while incremental marking: %s -> %s", obj_info(a), obj_info(b));
     }
 
 #if 1
@@ -8571,17 +8952,17 @@ gc_writebarrier_generational(VALUE a, VALUE b, rb_objspace_t *objspace)
             rgengc_remember(objspace, a);
         }
         RB_VM_LOCK_LEAVE_NO_BARRIER();
-	gc_report(1, objspace, "gc_writebarrier_generational: %s (remembered) -> %s\n", obj_info(a), obj_info(b));
+        gc_report(1, objspace, "gc_writebarrier_generational: %s (remembered) -> %s\n", obj_info(a), obj_info(b));
     }
 #else
     /* mark `b' and remember */
     MARK_IN_BITMAP(GET_HEAP_MARK_BITS(b), b);
     if (RVALUE_WB_UNPROTECTED(b)) {
-	gc_remember_unprotected(objspace, b);
+        gc_remember_unprotected(objspace, b);
     }
     else {
-	RVALUE_AGE_SET_OLD(objspace, b);
-	rgengc_remember(objspace, b);
+        RVALUE_AGE_SET_OLD(objspace, b);
+        rgengc_remember(objspace, b);
     }
 
     gc_report(1, objspace, "gc_writebarrier_generational: %s -> %s (remembered)\n", obj_info(a), obj_info(b));
@@ -8610,26 +8991,26 @@ gc_writebarrier_incremental(VALUE a, VALUE b, rb_objspace_t *objspace)
     gc_report(2, objspace, "gc_writebarrier_incremental: [LG] %p -> %s\n", (void *)a, obj_info(b));
 
     if (RVALUE_BLACK_P(a)) {
-	if (RVALUE_WHITE_P(b)) {
-	    if (!RVALUE_WB_UNPROTECTED(a)) {
-		gc_report(2, objspace, "gc_writebarrier_incremental: [IN] %p -> %s\n", (void *)a, obj_info(b));
-		gc_mark_from(objspace, b, a);
-	    }
-	}
-	else if (RVALUE_OLD_P(a) && !RVALUE_OLD_P(b)) {
-	    if (!RVALUE_WB_UNPROTECTED(b)) {
-		gc_report(1, objspace, "gc_writebarrier_incremental: [GN] %p -> %s\n", (void *)a, obj_info(b));
-		RVALUE_AGE_SET_OLD(objspace, b);
-
-		if (RVALUE_BLACK_P(b)) {
-		    gc_grey(objspace, b);
-		}
-	    }
-	    else {
-		gc_report(1, objspace, "gc_writebarrier_incremental: [LL] %p -> %s\n", (void *)a, obj_info(b));
-		gc_remember_unprotected(objspace, b);
-	    }
-	}
+        if (RVALUE_WHITE_P(b)) {
+            if (!RVALUE_WB_UNPROTECTED(a)) {
+                gc_report(2, objspace, "gc_writebarrier_incremental: [IN] %p -> %s\n", (void *)a, obj_info(b));
+                gc_mark_from(objspace, b, a);
+            }
+        }
+        else if (RVALUE_OLD_P(a) && !RVALUE_OLD_P(b)) {
+            if (!RVALUE_WB_UNPROTECTED(b)) {
+                gc_report(1, objspace, "gc_writebarrier_incremental: [GN] %p -> %s\n", (void *)a, obj_info(b));
+                RVALUE_AGE_SET_OLD(objspace, b);
+
+                if (RVALUE_BLACK_P(b)) {
+                    gc_grey(objspace, b);
+                }
+            }
+            else {
+                gc_report(1, objspace, "gc_writebarrier_incremental: [LL] %p -> %s\n", (void *)a, obj_info(b));
+                gc_remember_unprotected(objspace, b);
+            }
+        }
 
         if (UNLIKELY(objspace->flags.during_compacting)) {
             MARK_IN_BITMAP(GET_HEAP_PINNED_BITS(b), b);
@@ -8645,8 +9026,10 @@ rb_gc_writebarrier(VALUE a, VALUE b)
 {
     rb_objspace_t *objspace = &rb_objspace;
 
-    if (RGENGC_CHECK_MODE && SPECIAL_CONST_P(a)) rb_bug("rb_gc_writebarrier: a is special const");
-    if (RGENGC_CHECK_MODE && SPECIAL_CONST_P(b)) rb_bug("rb_gc_writebarrier: b is special const");
+    if (RGENGC_CHECK_MODE) {
+        if (SPECIAL_CONST_P(a)) rb_bug("rb_gc_writebarrier: a is special const: %"PRIxVALUE, a);
+        if (SPECIAL_CONST_P(b)) rb_bug("rb_gc_writebarrier: b is special const: %"PRIxVALUE, b);
+    }
 
   retry:
     if (!is_incremental_marking(objspace)) {
@@ -8680,33 +9063,37 @@ void
 rb_gc_writebarrier_unprotect(VALUE obj)
 {
     if (RVALUE_WB_UNPROTECTED(obj)) {
-	return;
+        return;
     }
     else {
-	rb_objspace_t *objspace = &rb_objspace;
+        rb_objspace_t *objspace = &rb_objspace;
 
-	gc_report(2, objspace, "rb_gc_writebarrier_unprotect: %s %s\n", obj_info(obj),
-		  rgengc_remembered(objspace, obj) ? " (already remembered)" : "");
+        gc_report(2, objspace, "rb_gc_writebarrier_unprotect: %s %s\n", obj_info(obj),
+                  rgengc_remembered(objspace, obj) ? " (already remembered)" : "");
 
-	if (RVALUE_OLD_P(obj)) {
-	    gc_report(1, objspace, "rb_gc_writebarrier_unprotect: %s\n", obj_info(obj));
-	    RVALUE_DEMOTE(objspace, obj);
-	    gc_mark_set(objspace, obj);
-	    gc_remember_unprotected(objspace, obj);
+        RB_VM_LOCK_ENTER_NO_BARRIER();
+        {
+            if (RVALUE_OLD_P(obj)) {
+                gc_report(1, objspace, "rb_gc_writebarrier_unprotect: %s\n", obj_info(obj));
+                RVALUE_DEMOTE(objspace, obj);
+                gc_mark_set(objspace, obj);
+                gc_remember_unprotected(objspace, obj);
 
 #if RGENGC_PROFILE
-	    objspace->profile.total_shade_operation_count++;
+                objspace->profile.total_shade_operation_count++;
 #if RGENGC_PROFILE >= 2
-	    objspace->profile.shade_operation_count_types[BUILTIN_TYPE(obj)]++;
+                objspace->profile.shade_operation_count_types[BUILTIN_TYPE(obj)]++;
 #endif /* RGENGC_PROFILE >= 2 */
 #endif /* RGENGC_PROFILE */
-	}
-	else {
-	    RVALUE_AGE_RESET(obj);
-	}
+            }
+            else {
+                RVALUE_AGE_RESET(obj);
+            }
 
-        RB_DEBUG_COUNTER_INC(obj_wb_unprotect);
-	MARK_IN_BITMAP(GET_HEAP_WB_UNPROTECTED_BITS(obj), obj);
+            RB_DEBUG_COUNTER_INC(obj_wb_unprotect);
+            MARK_IN_BITMAP(GET_HEAP_WB_UNPROTECTED_BITS(obj), obj);
+        }
+        RB_VM_LOCK_LEAVE_NO_BARRIER();
     }
 }
 
@@ -8721,14 +9108,14 @@ rb_gc_writebarrier_remember(VALUE obj)
     gc_report(1, objspace, "rb_gc_writebarrier_remember: %s\n", obj_info(obj));
 
     if (is_incremental_marking(objspace)) {
-	if (RVALUE_BLACK_P(obj)) {
-	    gc_grey(objspace, obj);
-	}
+        if (RVALUE_BLACK_P(obj)) {
+            gc_grey(objspace, obj);
+        }
     }
     else {
-	if (RVALUE_OLD_P(obj)) {
-	    rgengc_remember(objspace, obj);
-	}
+        if (RVALUE_OLD_P(obj)) {
+            rgengc_remember(objspace, obj);
+        }
     }
 }
 
@@ -8753,25 +9140,25 @@ rb_gc_unprotect_logging(void *objptr, const char *filename, int line)
     VALUE obj = (VALUE)objptr;
 
     if (rgengc_unprotect_logging_table == 0) {
-	rgengc_unprotect_logging_table = st_init_strtable();
-	atexit(rgengc_unprotect_logging_exit_func);
+        rgengc_unprotect_logging_table = st_init_strtable();
+        atexit(rgengc_unprotect_logging_exit_func);
     }
 
     if (RVALUE_WB_UNPROTECTED(obj) == 0) {
-	char buff[0x100];
-	st_data_t cnt = 1;
-	char *ptr = buff;
+        char buff[0x100];
+        st_data_t cnt = 1;
+        char *ptr = buff;
 
-	snprintf(ptr, 0x100 - 1, "%s|%s:%d", obj_info(obj), filename, line);
+        snprintf(ptr, 0x100 - 1, "%s|%s:%d", obj_info(obj), filename, line);
 
-	if (st_lookup(rgengc_unprotect_logging_table, (st_data_t)ptr, &cnt)) {
-	    cnt++;
-	}
-	else {
-	    ptr = (strdup)(buff);
-	    if (!ptr) rb_memerror();
-	}
-	st_insert(rgengc_unprotect_logging_table, (st_data_t)ptr, cnt);
+        if (st_lookup(rgengc_unprotect_logging_table, (st_data_t)ptr, &cnt)) {
+            cnt++;
+        }
+        else {
+            ptr = (strdup)(buff);
+            if (!ptr) rb_memerror();
+        }
+        st_insert(rgengc_unprotect_logging_table, (st_data_t)ptr, cnt);
     }
 }
 
@@ -8781,13 +9168,13 @@ rb_copy_wb_protected_attribute(VALUE dest, VALUE obj)
     rb_objspace_t *objspace = &rb_objspace;
 
     if (RVALUE_WB_UNPROTECTED(obj) && !RVALUE_WB_UNPROTECTED(dest)) {
-	if (!RVALUE_OLD_P(dest)) {
-	    MARK_IN_BITMAP(GET_HEAP_WB_UNPROTECTED_BITS(dest), dest);
-	    RVALUE_AGE_RESET_RAW(dest);
-	}
-	else {
-	    RVALUE_DEMOTE(objspace, dest);
-	}
+        if (!RVALUE_OLD_P(dest)) {
+            MARK_IN_BITMAP(GET_HEAP_WB_UNPROTECTED_BITS(dest), dest);
+            RVALUE_AGE_RESET_RAW(dest);
+        }
+        else {
+            RVALUE_DEMOTE(objspace, dest);
+        }
     }
 
     check_rvalue_consistency(dest);
@@ -8816,11 +9203,11 @@ rb_obj_gc_flags(VALUE obj, ID* flags, size_t max)
 
     if (!ID_marked) {
 #define I(s) ID_##s = rb_intern(#s);
-	I(marked);
-	I(wb_protected);
-	I(old);
-	I(marking);
-	I(uncollectible);
+        I(marked);
+        I(wb_protected);
+        I(old);
+        I(marking);
+        I(uncollectible);
         I(pinned);
 #undef I
     }
@@ -8879,7 +9266,7 @@ rb_gc_register_mark_object(VALUE obj)
         VALUE ary = rb_ary_last(0, 0, ary_ary);
 
         if (NIL_P(ary) || RARRAY_LEN(ary) >= MARK_OBJECT_ARY_BUCKET_SIZE) {
-            ary = rb_ary_tmp_new(MARK_OBJECT_ARY_BUCKET_SIZE);
+            ary = rb_ary_hidden_new(MARK_OBJECT_ARY_BUCKET_SIZE);
             rb_ary_push(ary_ary, ary);
         }
 
@@ -8894,10 +9281,23 @@ rb_gc_register_address(VALUE *addr)
     rb_objspace_t *objspace = &rb_objspace;
     struct gc_list *tmp;
 
+    VALUE obj = *addr;
+
     tmp = ALLOC(struct gc_list);
     tmp->next = global_list;
     tmp->varptr = addr;
     global_list = tmp;
+
+    /*
+     * Because some C extensions have assignment-then-register bugs,
+     * we guard `obj` here so that it would not get swept defensively.
+     */
+    RB_GC_GUARD(obj);
+    if (0 && !SPECIAL_CONST_P(obj)) {
+	rb_warn("Object is assigned to registering address already: %"PRIsVALUE,
+		rb_obj_class(obj));
+	rb_print_backtrace();
+    }
 }
 
 void
@@ -8907,19 +9307,19 @@ rb_gc_unregister_address(VALUE *addr)
     struct gc_list *tmp = global_list;
 
     if (tmp->varptr == addr) {
-	global_list = tmp->next;
-	xfree(tmp);
-	return;
+        global_list = tmp->next;
+        xfree(tmp);
+        return;
     }
     while (tmp->next) {
-	if (tmp->next->varptr == addr) {
-	    struct gc_list *t = tmp->next;
+        if (tmp->next->varptr == addr) {
+            struct gc_list *t = tmp->next;
 
-	    tmp->next = tmp->next->next;
-	    xfree(t);
-	    break;
-	}
-	tmp = tmp->next;
+            tmp->next = tmp->next->next;
+            xfree(t);
+            break;
+        }
+        tmp = tmp->next;
     }
 }
 
@@ -8963,7 +9363,7 @@ ready_to_gc(rb_objspace_t *objspace)
         return FALSE;
     }
     else {
-	return TRUE;
+        return TRUE;
     }
 }
 
@@ -8972,65 +9372,65 @@ gc_reset_malloc_info(rb_objspace_t *objspace, bool full_mark)
 {
     gc_prof_set_malloc_info(objspace);
     {
-	size_t inc = ATOMIC_SIZE_EXCHANGE(malloc_increase, 0);
-	size_t old_limit = malloc_limit;
-
-	if (inc > malloc_limit) {
-	    malloc_limit = (size_t)(inc * gc_params.malloc_limit_growth_factor);
-	    if (malloc_limit > gc_params.malloc_limit_max) {
-		malloc_limit = gc_params.malloc_limit_max;
-	    }
-	}
-	else {
-	    malloc_limit = (size_t)(malloc_limit * 0.98); /* magic number */
-	    if (malloc_limit < gc_params.malloc_limit_min) {
-		malloc_limit = gc_params.malloc_limit_min;
-	    }
-	}
-
-	if (0) {
-	    if (old_limit != malloc_limit) {
-		fprintf(stderr, "[%"PRIuSIZE"] malloc_limit: %"PRIuSIZE" -> %"PRIuSIZE"\n",
-			rb_gc_count(), old_limit, malloc_limit);
-	    }
-	    else {
-		fprintf(stderr, "[%"PRIuSIZE"] malloc_limit: not changed (%"PRIuSIZE")\n",
-			rb_gc_count(), malloc_limit);
-	    }
-	}
+        size_t inc = ATOMIC_SIZE_EXCHANGE(malloc_increase, 0);
+        size_t old_limit = malloc_limit;
+
+        if (inc > malloc_limit) {
+            malloc_limit = (size_t)(inc * gc_params.malloc_limit_growth_factor);
+            if (malloc_limit > gc_params.malloc_limit_max) {
+                malloc_limit = gc_params.malloc_limit_max;
+            }
+        }
+        else {
+            malloc_limit = (size_t)(malloc_limit * 0.98); /* magic number */
+            if (malloc_limit < gc_params.malloc_limit_min) {
+                malloc_limit = gc_params.malloc_limit_min;
+            }
+        }
+
+        if (0) {
+            if (old_limit != malloc_limit) {
+                fprintf(stderr, "[%"PRIuSIZE"] malloc_limit: %"PRIuSIZE" -> %"PRIuSIZE"\n",
+                        rb_gc_count(), old_limit, malloc_limit);
+            }
+            else {
+                fprintf(stderr, "[%"PRIuSIZE"] malloc_limit: not changed (%"PRIuSIZE")\n",
+                        rb_gc_count(), malloc_limit);
+            }
+        }
     }
 
     /* reset oldmalloc info */
 #if RGENGC_ESTIMATE_OLDMALLOC
     if (!full_mark) {
-	if (objspace->rgengc.oldmalloc_increase > objspace->rgengc.oldmalloc_increase_limit) {
-	    objspace->rgengc.need_major_gc |= GPR_FLAG_MAJOR_BY_OLDMALLOC;
-	    objspace->rgengc.oldmalloc_increase_limit =
-	      (size_t)(objspace->rgengc.oldmalloc_increase_limit * gc_params.oldmalloc_limit_growth_factor);
-
-	    if (objspace->rgengc.oldmalloc_increase_limit > gc_params.oldmalloc_limit_max) {
-		objspace->rgengc.oldmalloc_increase_limit = gc_params.oldmalloc_limit_max;
-	    }
-	}
-
-	if (0) fprintf(stderr, "%"PRIdSIZE"\t%d\t%"PRIuSIZE"\t%"PRIuSIZE"\t%"PRIdSIZE"\n",
-		       rb_gc_count(),
-		       objspace->rgengc.need_major_gc,
-		       objspace->rgengc.oldmalloc_increase,
-		       objspace->rgengc.oldmalloc_increase_limit,
-		       gc_params.oldmalloc_limit_max);
+        if (objspace->rgengc.oldmalloc_increase > objspace->rgengc.oldmalloc_increase_limit) {
+            objspace->rgengc.need_major_gc |= GPR_FLAG_MAJOR_BY_OLDMALLOC;
+            objspace->rgengc.oldmalloc_increase_limit =
+              (size_t)(objspace->rgengc.oldmalloc_increase_limit * gc_params.oldmalloc_limit_growth_factor);
+
+            if (objspace->rgengc.oldmalloc_increase_limit > gc_params.oldmalloc_limit_max) {
+                objspace->rgengc.oldmalloc_increase_limit = gc_params.oldmalloc_limit_max;
+            }
+        }
+
+        if (0) fprintf(stderr, "%"PRIdSIZE"\t%d\t%"PRIuSIZE"\t%"PRIuSIZE"\t%"PRIdSIZE"\n",
+                       rb_gc_count(),
+                       objspace->rgengc.need_major_gc,
+                       objspace->rgengc.oldmalloc_increase,
+                       objspace->rgengc.oldmalloc_increase_limit,
+                       gc_params.oldmalloc_limit_max);
     }
     else {
-	/* major GC */
-	objspace->rgengc.oldmalloc_increase = 0;
-
-	if ((objspace->profile.latest_gc_info & GPR_FLAG_MAJOR_BY_OLDMALLOC) == 0) {
-	    objspace->rgengc.oldmalloc_increase_limit =
-	      (size_t)(objspace->rgengc.oldmalloc_increase_limit / ((gc_params.oldmalloc_limit_growth_factor - 1)/10 + 1));
-	    if (objspace->rgengc.oldmalloc_increase_limit < gc_params.oldmalloc_limit_min) {
-		objspace->rgengc.oldmalloc_increase_limit = gc_params.oldmalloc_limit_min;
-	    }
-	}
+        /* major GC */
+        objspace->rgengc.oldmalloc_increase = 0;
+
+        if ((objspace->profile.latest_gc_info & GPR_FLAG_MAJOR_BY_OLDMALLOC) == 0) {
+            objspace->rgengc.oldmalloc_increase_limit =
+              (size_t)(objspace->rgengc.oldmalloc_increase_limit / ((gc_params.oldmalloc_limit_growth_factor - 1)/10 + 1));
+            if (objspace->rgengc.oldmalloc_increase_limit < gc_params.oldmalloc_limit_min) {
+                objspace->rgengc.oldmalloc_increase_limit = gc_params.oldmalloc_limit_min;
+            }
+        }
     }
 #endif
 }
@@ -9093,49 +9493,49 @@ gc_start(rb_objspace_t *objspace, unsigned int reason)
 #endif
 
     if (ruby_gc_stressful) {
-	int flag = FIXNUM_P(ruby_gc_stress_mode) ? FIX2INT(ruby_gc_stress_mode) : 0;
+        int flag = FIXNUM_P(ruby_gc_stress_mode) ? FIX2INT(ruby_gc_stress_mode) : 0;
 
-	if ((flag & (1<<gc_stress_no_major)) == 0) {
-	    do_full_mark = TRUE;
-	}
+        if ((flag & (1<<gc_stress_no_major)) == 0) {
+            do_full_mark = TRUE;
+        }
 
-	objspace->flags.immediate_sweep = !(flag & (1<<gc_stress_no_immediate_sweep));
+        objspace->flags.immediate_sweep = !(flag & (1<<gc_stress_no_immediate_sweep));
     }
     else {
-	if (objspace->rgengc.need_major_gc) {
-	    reason |= objspace->rgengc.need_major_gc;
-	    do_full_mark = TRUE;
-	}
-	else if (RGENGC_FORCE_MAJOR_GC) {
-	    reason = GPR_FLAG_MAJOR_BY_FORCE;
-	    do_full_mark = TRUE;
-	}
+        if (objspace->rgengc.need_major_gc) {
+            reason |= objspace->rgengc.need_major_gc;
+            do_full_mark = TRUE;
+        }
+        else if (RGENGC_FORCE_MAJOR_GC) {
+            reason = GPR_FLAG_MAJOR_BY_FORCE;
+            do_full_mark = TRUE;
+        }
 
-	objspace->rgengc.need_major_gc = GPR_FLAG_NONE;
+        objspace->rgengc.need_major_gc = GPR_FLAG_NONE;
     }
 
     if (do_full_mark && (reason & GPR_FLAG_MAJOR_MASK) == 0) {
-	reason |= GPR_FLAG_MAJOR_BY_FORCE; /* GC by CAPI, METHOD, and so on. */
+        reason |= GPR_FLAG_MAJOR_BY_FORCE; /* GC by CAPI, METHOD, and so on. */
     }
 
 #if GC_ENABLE_INCREMENTAL_MARK
     if (!GC_ENABLE_INCREMENTAL_MARK || objspace->flags.dont_incremental || immediate_mark) {
-	objspace->flags.during_incremental_marking = FALSE;
+        objspace->flags.during_incremental_marking = FALSE;
     }
     else {
-	objspace->flags.during_incremental_marking = do_full_mark;
+        objspace->flags.during_incremental_marking = do_full_mark;
     }
 #endif
 
     if (!GC_ENABLE_LAZY_SWEEP || objspace->flags.dont_incremental) {
-	objspace->flags.immediate_sweep = TRUE;
+        objspace->flags.immediate_sweep = TRUE;
     }
 
     if (objspace->flags.immediate_sweep) reason |= GPR_FLAG_IMMEDIATE_SWEEP;
 
     gc_report(1, objspace, "gc_start(reason: %x) => %u, %d, %d\n",
-	      reason,
-	      do_full_mark, !is_incremental_marking(objspace), objspace->flags.immediate_sweep);
+              reason,
+              do_full_mark, !is_incremental_marking(objspace), objspace->flags.immediate_sweep);
 
 #if USE_DEBUG_COUNTER
     RB_DEBUG_COUNTER_INC(gc_count);
@@ -9171,7 +9571,7 @@ gc_start(rb_objspace_t *objspace, unsigned int reason)
 
     gc_prof_timer_start(objspace);
     {
-	gc_marks(objspace, do_full_mark);
+        gc_marks(objspace, do_full_mark);
     }
     gc_prof_timer_stop(objspace);
 
@@ -9187,17 +9587,17 @@ gc_rest(rb_objspace_t *objspace)
 
     if (marking || sweeping) {
         unsigned int lock_lev;
-	gc_enter(objspace, gc_enter_event_rest, &lock_lev);
+        gc_enter(objspace, gc_enter_event_rest, &lock_lev);
 
         if (RGENGC_CHECK_MODE >= 2) gc_verify_internal_consistency(objspace);
 
-	if (is_incremental_marking(objspace)) {
+        if (is_incremental_marking(objspace)) {
             gc_marks_rest(objspace);
         }
-	if (is_lazy_sweeping(objspace)) {
-	    gc_sweep_rest(objspace);
-	}
-	gc_exit(objspace, gc_enter_event_rest, &lock_lev);
+        if (is_lazy_sweeping(objspace)) {
+            gc_sweep_rest(objspace);
+        }
+        gc_exit(objspace, gc_enter_event_rest, &lock_lev);
     }
 }
 
@@ -9211,18 +9611,18 @@ gc_current_status_fill(rb_objspace_t *objspace, char *buff)
 {
     int i = 0;
     if (is_marking(objspace)) {
-	buff[i++] = 'M';
-	if (is_full_marking(objspace))        buff[i++] = 'F';
+        buff[i++] = 'M';
+        if (is_full_marking(objspace))        buff[i++] = 'F';
 #if GC_ENABLE_INCREMENTAL_MARK
-	if (is_incremental_marking(objspace)) buff[i++] = 'I';
+        if (is_incremental_marking(objspace)) buff[i++] = 'I';
 #endif
     }
     else if (is_sweeping(objspace)) {
-	buff[i++] = 'S';
-	if (is_lazy_sweeping(objspace))      buff[i++] = 'L';
+        buff[i++] = 'S';
+        if (is_lazy_sweeping(objspace))      buff[i++] = 'L';
     }
     else {
-	buff[i++] = 'N';
+        buff[i++] = 'N';
     }
     buff[i] = '\0';
 }
@@ -9246,31 +9646,31 @@ static inline void
 gc_record(rb_objspace_t *objspace, int direction, const char *event)
 {
     if (direction == 0) { /* enter */
-	enter_count++;
-	enter_tick = tick();
-	gc_current_status_fill(objspace, last_gc_status);
+        enter_count++;
+        enter_tick = tick();
+        gc_current_status_fill(objspace, last_gc_status);
     }
     else { /* exit */
-	tick_t exit_tick = tick();
-	char current_gc_status[0x10];
-	gc_current_status_fill(objspace, current_gc_status);
+        tick_t exit_tick = tick();
+        char current_gc_status[0x10];
+        gc_current_status_fill(objspace, current_gc_status);
 #if 1
-	/* [last mutator time] [gc time] [event] */
-	fprintf(stderr, "%"PRItick"\t%"PRItick"\t%s\t[%s->%s|%c]\n",
-		enter_tick - last_exit_tick,
-		exit_tick - enter_tick,
-		event,
-		last_gc_status, current_gc_status,
-		(objspace->profile.latest_gc_info & GPR_FLAG_MAJOR_MASK) ? '+' : '-');
-	last_exit_tick = exit_tick;
+        /* [last mutator time] [gc time] [event] */
+        fprintf(stderr, "%"PRItick"\t%"PRItick"\t%s\t[%s->%s|%c]\n",
+                enter_tick - last_exit_tick,
+                exit_tick - enter_tick,
+                event,
+                last_gc_status, current_gc_status,
+                (objspace->profile.latest_gc_info & GPR_FLAG_MAJOR_MASK) ? '+' : '-');
+        last_exit_tick = exit_tick;
 #else
-	/* [enter_tick] [gc time] [event] */
-	fprintf(stderr, "%"PRItick"\t%"PRItick"\t%s\t[%s->%s|%c]\n",
-		enter_tick,
-		exit_tick - enter_tick,
-		event,
-		last_gc_status, current_gc_status,
-		(objspace->profile.latest_gc_info & GPR_FLAG_MAJOR_MASK) ? '+' : '-');
+        /* [enter_tick] [gc time] [event] */
+        fprintf(stderr, "%"PRItick"\t%"PRItick"\t%s\t[%s->%s|%c]\n",
+                enter_tick,
+                exit_tick - enter_tick,
+                event,
+                last_gc_status, current_gc_status,
+                (objspace->profile.latest_gc_info & GPR_FLAG_MAJOR_MASK) ? '+' : '-');
 #endif
     }
 }
@@ -9392,8 +9792,6 @@ gc_enter(rb_objspace_t *objspace, enum gc_enter_event event, unsigned int *lock_
     if (UNLIKELY(during_gc != 0)) rb_bug("during_gc != 0");
     if (RGENGC_CHECK_MODE >= 3) gc_verify_internal_consistency(objspace);
 
-    mjit_gc_start_hook();
-
     during_gc = TRUE;
     RUBY_DEBUG_LOG("%s (%s)",gc_enter_event_cstr(event), gc_current_status(objspace));
     gc_report(1, objspace, "gc_enter: %s [%s]\n", gc_enter_event_cstr(event), gc_current_status(objspace));
@@ -9412,7 +9810,6 @@ gc_exit(rb_objspace_t *objspace, enum gc_enter_event event, unsigned int *lock_l
     gc_report(1, objspace, "gc_exit: %s [%s]\n", gc_enter_event_cstr(event), gc_current_status(objspace));
     during_gc = FALSE;
 
-    mjit_gc_exit_hook();
     gc_exit_clock(objspace, event);
     RB_VM_LOCK_LEAVE_LEV(lock_lev);
 
@@ -9437,20 +9834,20 @@ garbage_collect_with_gvl(rb_objspace_t *objspace, unsigned int reason)
 {
     if (dont_gc_val()) return TRUE;
     if (ruby_thread_has_gvl_p()) {
-	return garbage_collect(objspace, reason);
+        return garbage_collect(objspace, reason);
     }
     else {
-	if (ruby_native_thread_p()) {
-	    struct objspace_and_reason oar;
-	    oar.objspace = objspace;
-	    oar.reason = reason;
-	    return (int)(VALUE)rb_thread_call_with_gvl(gc_with_gvl, (void *)&oar);
-	}
-	else {
-	    /* no ruby thread */
-	    fprintf(stderr, "[FATAL] failed to allocate memory\n");
-	    exit(EXIT_FAILURE);
-	}
+        if (ruby_native_thread_p()) {
+            struct objspace_and_reason oar;
+            oar.objspace = objspace;
+            oar.reason = reason;
+            return (int)(VALUE)rb_thread_call_with_gvl(gc_with_gvl, (void *)&oar);
+        }
+        else {
+            /* no ruby thread */
+            fprintf(stderr, "[FATAL] failed to allocate memory\n");
+            exit(EXIT_FAILURE);
+        }
     }
 }
 
@@ -9465,17 +9862,7 @@ gc_start_internal(rb_execution_context_t *ec, VALUE self, VALUE full_mark, VALUE
 
     /* For now, compact implies full mark / sweep, so ignore other flags */
     if (RTEST(compact)) {
-        /* If not MinGW, Windows, or does not have mmap, we cannot use mprotect for
-         * the read barrier, so we must disable compaction. */
-#if !defined(__MINGW32__) && !defined(_WIN32)
-        if (!HEAP_PAGE_ALLOC_USE_MMAP) {
-            rb_raise(rb_eNotImpError, "Compaction isn't available on this platform");
-        }
-#endif
-
-#if !GC_COMPACTION_SUPPORTED
-        rb_raise(rb_eNotImpError, "Compaction isn't available on this platform");
-#endif
+        GC_ASSERT(GC_COMPACTION_SUPPORTED);
 
         reason |= GPR_FLAG_COMPACT;
     }
@@ -9548,8 +9935,19 @@ gc_is_moveable_obj(rb_objspace_t *objspace, VALUE obj)
     return FALSE;
 }
 
+/* Used in places that could malloc, which can cause the GC to run. We need to
+ * temporarily disable the GC to allow the malloc to happen. */
+#define COULD_MALLOC_REGION_START() \
+    GC_ASSERT(during_gc); \
+    VALUE _already_disabled = rb_gc_disable_no_rest(); \
+    during_gc = false;
+
+#define COULD_MALLOC_REGION_END() \
+    during_gc = true; \
+    if (_already_disabled == Qfalse) rb_objspace_gc_enable(objspace);
+
 static VALUE
-gc_move(rb_objspace_t *objspace, VALUE scan, VALUE free, size_t slot_size)
+gc_move(rb_objspace_t *objspace, VALUE scan, VALUE free, size_t src_slot_size, size_t slot_size)
 {
     int marked;
     int wb_unprotected;
@@ -9576,11 +9974,12 @@ gc_move(rb_objspace_t *objspace, VALUE scan, VALUE free, size_t slot_size)
     CLEAR_IN_BITMAP(GET_HEAP_MARKING_BITS((VALUE)src), (VALUE)src);
 
     if (FL_TEST((VALUE)src, FL_EXIVAR)) {
-        /* Same deal as below. Generic ivars are held in st tables.
-         * Resizing the table could cause a GC to happen and we can't allow it */
-        VALUE already_disabled = rb_gc_disable_no_rest();
-        rb_mv_generic_ivar((VALUE)src, (VALUE)dest);
-        if (already_disabled == Qfalse) rb_objspace_gc_enable(objspace);
+        /* Resizing the st table could cause a malloc */
+        COULD_MALLOC_REGION_START();
+        {
+            rb_mv_generic_ivar((VALUE)src, (VALUE)dest);
+        }
+        COULD_MALLOC_REGION_END();
     }
 
     st_data_t srcid = (st_data_t)src, id;
@@ -9589,18 +9988,26 @@ gc_move(rb_objspace_t *objspace, VALUE scan, VALUE free, size_t slot_size)
      * the object to object id mapping. */
     if (st_lookup(objspace->obj_to_id_tbl, srcid, &id)) {
         gc_report(4, objspace, "Moving object with seen id: %p -> %p\n", (void *)src, (void *)dest);
-        /* inserting in the st table can cause the GC to run. We need to
-         * prevent re-entry in to the GC since `gc_move` is running in the GC,
-         * so temporarily disable the GC around the st table mutation */
-        VALUE already_disabled = rb_gc_disable_no_rest();
-        st_delete(objspace->obj_to_id_tbl, &srcid, 0);
-        st_insert(objspace->obj_to_id_tbl, (st_data_t)dest, id);
-        if (already_disabled == Qfalse) rb_objspace_gc_enable(objspace);
+        /* Resizing the st table could cause a malloc */
+        COULD_MALLOC_REGION_START();
+        {
+            st_delete(objspace->obj_to_id_tbl, &srcid, 0);
+            st_insert(objspace->obj_to_id_tbl, (st_data_t)dest, id);
+        }
+        COULD_MALLOC_REGION_END();
     }
 
     /* Move the object */
-    memcpy(dest, src, slot_size);
-    memset(src, 0, slot_size);
+    memcpy(dest, src, MIN(src_slot_size, slot_size));
+
+    if (RVALUE_OVERHEAD > 0) {
+        void *dest_overhead = (void *)(((uintptr_t)dest) + slot_size - RVALUE_OVERHEAD);
+        void *src_overhead = (void *)(((uintptr_t)src) + src_slot_size - RVALUE_OVERHEAD);
+
+        memcpy(dest_overhead, src_overhead, RVALUE_OVERHEAD);
+    }
+
+    memset(src, 0, src_slot_size);
 
     /* Set bits for object in new location */
     if (marking) {
@@ -9640,6 +10047,7 @@ gc_move(rb_objspace_t *objspace, VALUE scan, VALUE free, size_t slot_size)
     return (VALUE)src;
 }
 
+#if GC_CAN_COMPILE_COMPACTION
 static int
 compare_free_slots(const void *left, const void *right, void *dummy)
 {
@@ -9688,31 +10096,76 @@ gc_sort_heap_by_empty_slots(rb_objspace_t *objspace)
         free(page_list);
     }
 }
+#endif
 
 static void
 gc_ref_update_array(rb_objspace_t * objspace, VALUE v)
 {
-    long i, len;
+    if (ARY_SHARED_P(v)) {
+#if USE_RVARGC
+        VALUE old_root = RARRAY(v)->as.heap.aux.shared_root;
+#endif
 
-    if (FL_TEST(v, ELTS_SHARED))
-        return;
+        UPDATE_IF_MOVED(objspace, RARRAY(v)->as.heap.aux.shared_root);
+
+#if USE_RVARGC
+        VALUE new_root = RARRAY(v)->as.heap.aux.shared_root;
+        // If the root is embedded and its location has changed
+        if (ARY_EMBED_P(new_root) && new_root != old_root) {
+            size_t offset = (size_t)(RARRAY(v)->as.heap.ptr - RARRAY(old_root)->as.ary);
+            GC_ASSERT(RARRAY(v)->as.heap.ptr >= RARRAY(old_root)->as.ary);
+            RARRAY(v)->as.heap.ptr = RARRAY(new_root)->as.ary + offset;
+        }
+#endif
+    }
+    else {
+        long len = RARRAY_LEN(v);
+
+        if (len > 0) {
+            VALUE *ptr = (VALUE *)RARRAY_CONST_PTR_TRANSIENT(v);
+            for (long i = 0; i < len; i++) {
+                UPDATE_IF_MOVED(objspace, ptr[i]);
+            }
+        }
 
-    len = RARRAY_LEN(v);
-    if (len > 0) {
-        VALUE *ptr = (VALUE *)RARRAY_CONST_PTR_TRANSIENT(v);
-        for (i = 0; i < len; i++) {
-            UPDATE_IF_MOVED(objspace, ptr[i]);
+#if USE_RVARGC
+        if (rb_gc_obj_slot_size(v) >= rb_ary_size_as_embedded(v)) {
+            if (rb_ary_embeddable_p(v)) {
+                rb_ary_make_embedded(v);
+            }
         }
+#endif
     }
 }
 
 static void
-gc_ref_update_object(rb_objspace_t * objspace, VALUE v)
+gc_ref_update_object(rb_objspace_t *objspace, VALUE v)
 {
     VALUE *ptr = ROBJECT_IVPTR(v);
 
-    uint32_t i, len = ROBJECT_NUMIV(v);
-    for (i = 0; i < len; i++) {
+    if (rb_shape_obj_too_complex(v)) {
+        rb_gc_update_tbl_refs(ROBJECT_IV_HASH(v));
+        return;
+    }
+
+#if USE_RVARGC
+    size_t slot_size = rb_gc_obj_slot_size(v);
+    size_t embed_size = rb_obj_embedded_size(ROBJECT_IV_CAPACITY(v));
+    if (slot_size >= embed_size && !RB_FL_TEST_RAW(v, ROBJECT_EMBED)) {
+        // Object can be re-embedded
+        memcpy(ROBJECT(v)->as.ary, ptr, sizeof(VALUE) * ROBJECT_IV_COUNT(v));
+        RB_FL_SET_RAW(v, ROBJECT_EMBED);
+        if (ROBJ_TRANSIENT_P(v)) {
+            ROBJ_TRANSIENT_UNSET(v);
+        }
+        else {
+            xfree(ptr);
+        }
+        ptr = ROBJECT(v)->as.ary;
+    }
+#endif
+
+    for (uint32_t i = 0; i < ROBJECT_IV_COUNT(v); i++) {
         UPDATE_IF_MOVED(objspace, ptr[i]);
     }
 }
@@ -9959,8 +10412,7 @@ rb_gc_location(VALUE value)
     VALUE destination;
 
     if (!SPECIAL_CONST_P(value)) {
-        void *poisoned = asan_poisoned_object_p(value);
-        asan_unpoison_object(value, false);
+        void *poisoned = asan_unpoison_object_temporary(value);
 
         if (BUILTIN_TYPE(value) == T_MOVED) {
             destination = (VALUE)RMOVED(value)->destination;
@@ -10040,9 +10492,14 @@ static enum rb_id_table_iterator_result
 update_cvc_tbl_i(VALUE cvc_entry, void *data)
 {
     struct rb_cvar_class_tbl_entry *entry;
+    rb_objspace_t * objspace = (rb_objspace_t *)data;
 
     entry = (struct rb_cvar_class_tbl_entry *)cvc_entry;
 
+    if (entry->cref) {
+        TYPED_UPDATE_IF_MOVED(objspace, rb_cref_t *, entry->cref);
+    }
+
     entry->class_value = rb_gc_location(entry->class_value);
 
     return ID_TABLE_CONTINUE;
@@ -10058,6 +10515,28 @@ update_cvc_tbl(rb_objspace_t *objspace, VALUE klass)
 }
 
 static enum rb_id_table_iterator_result
+mark_cvc_tbl_i(VALUE cvc_entry, void *data)
+{
+    struct rb_cvar_class_tbl_entry *entry;
+
+    entry = (struct rb_cvar_class_tbl_entry *)cvc_entry;
+
+    RUBY_ASSERT(entry->cref == 0 || (BUILTIN_TYPE((VALUE)entry->cref) == T_IMEMO && IMEMO_TYPE_P(entry->cref, imemo_cref)));
+    rb_gc_mark((VALUE) entry->cref);
+
+    return ID_TABLE_CONTINUE;
+}
+
+static void
+mark_cvc_tbl(rb_objspace_t *objspace, VALUE klass)
+{
+    struct rb_id_table *tbl = RCLASS_CVC_TBL(klass);
+    if (tbl) {
+        rb_id_table_foreach_values(tbl, mark_cvc_tbl_i, objspace);
+    }
+}
+
+static enum rb_id_table_iterator_result
 update_const_table(VALUE value, void *data)
 {
     rb_const_entry_t *ce = (rb_const_entry_t *)value;
@@ -10090,26 +10569,13 @@ update_subclass_entries(rb_objspace_t *objspace, rb_subclass_entry_t *entry)
     }
 }
 
-static int
-update_iv_index_tbl_i(st_data_t key, st_data_t value, st_data_t arg)
-{
-    rb_objspace_t *objspace = (rb_objspace_t *)arg;
-    struct rb_iv_index_tbl_entry *ent = (struct rb_iv_index_tbl_entry *)value;
-    UPDATE_IF_MOVED(objspace, ent->class_value);
-    return ST_CONTINUE;
-}
-
 static void
 update_class_ext(rb_objspace_t *objspace, rb_classext_t *ext)
 {
     UPDATE_IF_MOVED(objspace, ext->origin_);
+    UPDATE_IF_MOVED(objspace, ext->includer);
     UPDATE_IF_MOVED(objspace, ext->refined_class);
     update_subclass_entries(objspace, ext->subclasses);
-
-    // ext->iv_index_tbl
-    if (ext->iv_index_tbl) {
-        st_foreach(ext->iv_index_tbl, update_iv_index_tbl_i, (st_data_t)objspace);
-    }
 }
 
 static void
@@ -10141,7 +10607,9 @@ gc_update_object_references(rb_objspace_t *objspace, VALUE obj)
         update_cvc_tbl(objspace, obj);
         update_superclasses(objspace, obj);
 
-        gc_update_tbl_refs(objspace, RCLASS_IV_TBL(obj));
+        for (attr_index_t i = 0; i < RCLASS_IV_COUNT(obj); i++) {
+            UPDATE_IF_MOVED(objspace, RCLASS_IVPTR(obj)[i]);
+        }
 
         update_class_ext(objspace, RCLASS_EXT(obj));
         update_const_tbl(objspace, RCLASS_CONST_TBL(obj));
@@ -10156,9 +10624,6 @@ gc_update_object_references(rb_objspace_t *objspace, VALUE obj)
             UPDATE_IF_MOVED(objspace, RCLASS(obj)->super);
         }
         if (!RCLASS_EXT(obj)) break;
-        if (RCLASS_IV_TBL(obj)) {
-            gc_update_tbl_refs(objspace, RCLASS_IV_TBL(obj));
-        }
         update_class_ext(objspace, RCLASS_EXT(obj));
         update_m_tbl(objspace, RCLASS_CALLABLE_M_TBL(obj));
         update_cc_tbl(objspace, obj);
@@ -10177,12 +10642,7 @@ gc_update_object_references(rb_objspace_t *objspace, VALUE obj)
         return;
 
       case T_ARRAY:
-        if (FL_TEST(obj, ELTS_SHARED)) {
-            UPDATE_IF_MOVED(objspace, any->as.array.as.heap.aux.shared_root);
-        }
-        else {
-            gc_ref_update_array(objspace, obj);
-        }
+        gc_ref_update_array(objspace, obj);
         break;
 
       case T_HASH:
@@ -10191,23 +10651,33 @@ gc_update_object_references(rb_objspace_t *objspace, VALUE obj)
         break;
 
       case T_STRING:
-        if (STR_SHARED_P(obj)) {
+        {
+#if USE_RVARGC
+#endif
+
+            if (STR_SHARED_P(obj)) {
 #if USE_RVARGC
-            VALUE orig_shared = any->as.string.as.heap.aux.shared;
+                VALUE old_root = any->as.string.as.heap.aux.shared;
 #endif
-            UPDATE_IF_MOVED(objspace, any->as.string.as.heap.aux.shared);
+                UPDATE_IF_MOVED(objspace, any->as.string.as.heap.aux.shared);
 #if USE_RVARGC
-            VALUE shared = any->as.string.as.heap.aux.shared;
-            if (STR_EMBED_P(shared)) {
-                size_t offset = (size_t)any->as.string.as.heap.ptr - (size_t)RSTRING(orig_shared)->as.embed.ary;
-                GC_ASSERT(any->as.string.as.heap.ptr >= RSTRING(orig_shared)->as.embed.ary);
-                GC_ASSERT(offset <= (size_t)RSTRING(shared)->as.embed.len);
-                any->as.string.as.heap.ptr = RSTRING(shared)->as.embed.ary + offset;
+                VALUE new_root = any->as.string.as.heap.aux.shared;
+                rb_str_update_shared_ary(obj, old_root, new_root);
+#endif
+            }
+
+#if USE_RVARGC
+            /* If, after move the string is not embedded, and can fit in the
+             * slot it's been placed in, then re-embed it. */
+            if (rb_gc_obj_slot_size(obj) >= rb_str_size_as_embedded(obj)) {
+                if (!STR_EMBED_P(obj) && rb_str_reembeddable_p(obj)) {
+                    rb_str_make_embedded(obj);
+                }
             }
 #endif
-        }
-        break;
 
+            break;
+        }
       case T_DATA:
         /* Call the compaction callback, if it exists */
         {
@@ -10298,15 +10768,14 @@ static int
 gc_ref_update(void *vstart, void *vend, size_t stride, rb_objspace_t * objspace, struct heap_page *page)
 {
     VALUE v = (VALUE)vstart;
-    asan_unpoison_memory_region(&page->freelist, sizeof(RVALUE*), false);
-    asan_poison_memory_region(&page->freelist, sizeof(RVALUE*));
+    asan_unlock_freelist(page);
+    asan_lock_freelist(page);
     page->flags.has_uncollectible_shady_objects = FALSE;
     page->flags.has_remembered_objects = FALSE;
 
     /* For each object on the page */
     for (; v != (VALUE)vend; v += stride) {
-        void *poisoned = asan_poisoned_object_p(v);
-        asan_unpoison_object(v, false);
+        void *poisoned = asan_unpoison_object_temporary(v);
 
         switch (BUILTIN_TYPE(v)) {
           case T_NONE:
@@ -10378,14 +10847,29 @@ gc_update_references(rb_objspace_t *objspace)
     gc_update_table_refs(objspace, finalizer_table);
 }
 
+#if GC_CAN_COMPILE_COMPACTION
+/*
+ *  call-seq:
+ *     GC.latest_compact_info -> hash
+ *
+ * Returns information about object moved in the most recent \GC compaction.
+ *
+ * The returned hash has two keys :considered and :moved.  The hash for
+ * :considered lists the number of objects that were considered for movement
+ * by the compactor, and the :moved hash lists the number of objects that
+ * were actually moved.  Some objects can't be moved (maybe they were pinned)
+ * so these numbers can be used to calculate compaction efficiency.
+ */
 static VALUE
-gc_compact_stats(rb_execution_context_t *ec, VALUE self)
+gc_compact_stats(VALUE self)
 {
     size_t i;
     rb_objspace_t *objspace = &rb_objspace;
     VALUE h = rb_hash_new();
     VALUE considered = rb_hash_new();
     VALUE moved = rb_hash_new();
+    VALUE moved_up = rb_hash_new();
+    VALUE moved_down = rb_hash_new();
 
     for (i=0; i<T_MASK; i++) {
         if (objspace->rcompactor.considered_count_table[i]) {
@@ -10395,14 +10879,28 @@ gc_compact_stats(rb_execution_context_t *ec, VALUE self)
         if (objspace->rcompactor.moved_count_table[i]) {
             rb_hash_aset(moved, type_sym(i), SIZET2NUM(objspace->rcompactor.moved_count_table[i]));
         }
+
+        if (objspace->rcompactor.moved_up_count_table[i]) {
+            rb_hash_aset(moved_up, type_sym(i), SIZET2NUM(objspace->rcompactor.moved_up_count_table[i]));
+        }
+
+        if (objspace->rcompactor.moved_down_count_table[i]) {
+            rb_hash_aset(moved_down, type_sym(i), SIZET2NUM(objspace->rcompactor.moved_down_count_table[i]));
+        }
     }
 
     rb_hash_aset(h, ID2SYM(rb_intern("considered")), considered);
     rb_hash_aset(h, ID2SYM(rb_intern("moved")), moved);
+    rb_hash_aset(h, ID2SYM(rb_intern("moved_up")), moved_up);
+    rb_hash_aset(h, ID2SYM(rb_intern("moved_down")), moved_down);
 
     return h;
 }
+#else
+#  define gc_compact_stats rb_f_notimplement
+#endif
 
+#if GC_CAN_COMPILE_COMPACTION
 static void
 root_obj_check_moved_i(const char *category, VALUE obj, void *data)
 {
@@ -10429,8 +10927,7 @@ heap_check_moved_i(void *vstart, void *vend, size_t stride, void *data)
             /* Moved object still on the heap, something may have a reference. */
         }
         else {
-            void *poisoned = asan_poisoned_object_p(v);
-            asan_unpoison_object(v, false);
+            void *poisoned = asan_unpoison_object_temporary(v);
 
             switch (BUILTIN_TYPE(v)) {
               case T_NONE:
@@ -10452,32 +10949,66 @@ heap_check_moved_i(void *vstart, void *vend, size_t stride, void *data)
     return 0;
 }
 
+/*
+ *  call-seq:
+ *     GC.compact
+ *
+ * This function compacts objects together in Ruby's heap.  It eliminates
+ * unused space (or fragmentation) in the heap by moving objects in to that
+ * unused space.  This function returns a hash which contains statistics about
+ * which objects were moved.  See <tt>GC.latest_gc_info</tt> for details about
+ * compaction statistics.
+ *
+ * This method is implementation specific and not expected to be implemented
+ * in any implementation besides MRI.
+ *
+ * To test whether \GC compaction is supported, use the idiom:
+ *
+ *   GC.respond_to?(:compact)
+ */
 static VALUE
-gc_compact(rb_execution_context_t *ec, VALUE self)
+gc_compact(VALUE self)
 {
     /* Run GC with compaction enabled */
-    gc_start_internal(ec, self, Qtrue, Qtrue, Qtrue, Qtrue);
+    gc_start_internal(NULL, self, Qtrue, Qtrue, Qtrue, Qtrue);
 
-    return gc_compact_stats(ec, self);
+    return gc_compact_stats(self);
 }
+#else
+#  define gc_compact rb_f_notimplement
+#endif
 
+#if GC_CAN_COMPILE_COMPACTION
 static VALUE
-gc_verify_compaction_references(rb_execution_context_t *ec, VALUE self, VALUE double_heap, VALUE toward_empty)
+gc_verify_compaction_references(rb_execution_context_t *ec, VALUE self, VALUE double_heap, VALUE expand_heap, VALUE toward_empty)
 {
     rb_objspace_t *objspace = &rb_objspace;
 
     /* Clear the heap. */
-    gc_start_internal(ec, self, Qtrue, Qtrue, Qtrue, Qfalse);
+    gc_start_internal(NULL, self, Qtrue, Qtrue, Qtrue, Qfalse);
+    size_t growth_slots = gc_params.heap_init_slots;
+
+    if (RTEST(double_heap)) {
+        rb_warn("double_heap is deprecated, please use expand_heap instead");
+    }
 
     RB_VM_LOCK_ENTER();
     {
         gc_rest(objspace);
 
-        if (RTEST(double_heap)) {
+        /* if both double_heap and expand_heap are set, expand_heap takes precedence */
+        if (RTEST(double_heap) || RTEST(expand_heap)) {
             for (int i = 0; i < SIZE_POOL_COUNT; i++) {
                 rb_size_pool_t *size_pool = &size_pools[i];
                 rb_heap_t *heap = SIZE_POOL_EDEN_HEAP(size_pool);
-                heap_add_pages(objspace, size_pool, heap, heap->total_pages);
+
+                if (RTEST(expand_heap)) {
+                    size_t required_pages = growth_slots / size_pool->slot_size;
+                    heap_add_pages(objspace, size_pool, heap, MAX(required_pages, heap->total_pages));
+                }
+                else {
+                    heap_add_pages(objspace, size_pool, heap, heap->total_pages);
+                }
             }
         }
 
@@ -10487,13 +11018,16 @@ gc_verify_compaction_references(rb_execution_context_t *ec, VALUE self, VALUE do
     }
     RB_VM_LOCK_LEAVE();
 
-    gc_start_internal(ec, self, Qtrue, Qtrue, Qtrue, Qtrue);
+    gc_start_internal(NULL, self, Qtrue, Qtrue, Qtrue, Qtrue);
 
     objspace_reachable_objects_from_root(objspace, root_obj_check_moved_i, NULL);
     objspace_each_objects(objspace, heap_check_moved_i, NULL, TRUE);
 
-    return gc_compact_stats(ec, self);
+    return gc_compact_stats(self);
 }
+#else
+#  define gc_verify_compaction_references (rb_builtin_arity3_function_type)rb_f_notimplement
+#endif
 
 VALUE
 rb_gc_start(void)
@@ -10549,7 +11083,7 @@ gc_count(rb_execution_context_t *ec, VALUE self)
 static VALUE
 gc_info_decode(rb_objspace_t *objspace, const VALUE hash_or_key, const unsigned int orig_flags)
 {
-    static VALUE sym_major_by = Qnil, sym_gc_by, sym_immediate_sweep, sym_have_finalizer, sym_state;
+    static VALUE sym_major_by = Qnil, sym_gc_by, sym_immediate_sweep, sym_have_finalizer, sym_state, sym_need_major_by;
     static VALUE sym_nofree, sym_oldgen, sym_shady, sym_force, sym_stress;
 #if RGENGC_ESTIMATE_OLDMALLOC
     static VALUE sym_oldmalloc;
@@ -10557,7 +11091,7 @@ gc_info_decode(rb_objspace_t *objspace, const VALUE hash_or_key, const unsigned
     static VALUE sym_newobj, sym_malloc, sym_method, sym_capi;
     static VALUE sym_none, sym_marking, sym_sweeping;
     VALUE hash = Qnil, key = Qnil;
-    VALUE major_by;
+    VALUE major_by, need_major_by;
     unsigned int flags = orig_flags ? orig_flags : objspace->profile.latest_gc_info;
 
     if (SYMBOL_P(hash_or_key)) {
@@ -10577,6 +11111,7 @@ gc_info_decode(rb_objspace_t *objspace, const VALUE hash_or_key, const unsigned
         S(immediate_sweep);
         S(have_finalizer);
         S(state);
+        S(need_major_by);
 
         S(stress);
         S(nofree);
@@ -10614,6 +11149,20 @@ gc_info_decode(rb_objspace_t *objspace, const VALUE hash_or_key, const unsigned
       Qnil;
     SET(major_by, major_by);
 
+    if (orig_flags == 0) { /* set need_major_by only if flags not set explicitly */
+        unsigned int need_major_flags = objspace->rgengc.need_major_gc;
+        need_major_by =
+            (need_major_flags & GPR_FLAG_MAJOR_BY_NOFREE) ? sym_nofree :
+            (need_major_flags & GPR_FLAG_MAJOR_BY_OLDGEN) ? sym_oldgen :
+            (need_major_flags & GPR_FLAG_MAJOR_BY_SHADY)  ? sym_shady :
+            (need_major_flags & GPR_FLAG_MAJOR_BY_FORCE)  ? sym_force :
+#if RGENGC_ESTIMATE_OLDMALLOC
+            (need_major_flags & GPR_FLAG_MAJOR_BY_OLDMALLOC) ? sym_oldmalloc :
+#endif
+            Qnil;
+        SET(need_major_by, need_major_by);
+    }
+
     SET(gc_by,
         (flags & GPR_FLAG_NEWOBJ) ? sym_newobj :
         (flags & GPR_FLAG_MALLOC) ? sym_malloc :
@@ -10711,44 +11260,44 @@ setup_gc_stat_symbols(void)
 {
     if (gc_stat_symbols[0] == 0) {
 #define S(s) gc_stat_symbols[gc_stat_sym_##s] = ID2SYM(rb_intern_const(#s))
-	S(count);
+        S(count);
         S(time);
-	S(heap_allocated_pages);
-	S(heap_sorted_length);
-	S(heap_allocatable_pages);
-	S(heap_available_slots);
-	S(heap_live_slots);
-	S(heap_free_slots);
-	S(heap_final_slots);
-	S(heap_marked_slots);
-	S(heap_eden_pages);
-	S(heap_tomb_pages);
-	S(total_allocated_pages);
-	S(total_freed_pages);
-	S(total_allocated_objects);
-	S(total_freed_objects);
-	S(malloc_increase_bytes);
-	S(malloc_increase_bytes_limit);
-	S(minor_gc_count);
-	S(major_gc_count);
-	S(compact_count);
-	S(read_barrier_faults);
-	S(total_moved_objects);
-	S(remembered_wb_unprotected_objects);
-	S(remembered_wb_unprotected_objects_limit);
-	S(old_objects);
-	S(old_objects_limit);
+        S(heap_allocated_pages);
+        S(heap_sorted_length);
+        S(heap_allocatable_pages);
+        S(heap_available_slots);
+        S(heap_live_slots);
+        S(heap_free_slots);
+        S(heap_final_slots);
+        S(heap_marked_slots);
+        S(heap_eden_pages);
+        S(heap_tomb_pages);
+        S(total_allocated_pages);
+        S(total_freed_pages);
+        S(total_allocated_objects);
+        S(total_freed_objects);
+        S(malloc_increase_bytes);
+        S(malloc_increase_bytes_limit);
+        S(minor_gc_count);
+        S(major_gc_count);
+        S(compact_count);
+        S(read_barrier_faults);
+        S(total_moved_objects);
+        S(remembered_wb_unprotected_objects);
+        S(remembered_wb_unprotected_objects_limit);
+        S(old_objects);
+        S(old_objects_limit);
 #if RGENGC_ESTIMATE_OLDMALLOC
-	S(oldmalloc_increase_bytes);
-	S(oldmalloc_increase_bytes_limit);
+        S(oldmalloc_increase_bytes);
+        S(oldmalloc_increase_bytes_limit);
 #endif
 #if RGENGC_PROFILE
-	S(total_generated_normal_object_count);
-	S(total_generated_shady_object_count);
-	S(total_shade_operation_count);
-	S(total_promoted_count);
-	S(total_remembered_normal_object_count);
-	S(total_remembered_shady_object_count);
+        S(total_generated_normal_object_count);
+        S(total_generated_shady_object_count);
+        S(total_shade_operation_count);
+        S(total_promoted_count);
+        S(total_remembered_normal_object_count);
+        S(total_remembered_shady_object_count);
 #endif /* RGENGC_PROFILE */
 #undef S
     }
@@ -10763,20 +11312,20 @@ gc_stat_internal(VALUE hash_or_sym)
     setup_gc_stat_symbols();
 
     if (RB_TYPE_P(hash_or_sym, T_HASH)) {
-	hash = hash_or_sym;
+        hash = hash_or_sym;
     }
     else if (SYMBOL_P(hash_or_sym)) {
-	key = hash_or_sym;
+        key = hash_or_sym;
     }
     else {
-	rb_raise(rb_eTypeError, "non-hash or symbol argument");
+        rb_raise(rb_eTypeError, "non-hash or symbol argument");
     }
 
 #define SET(name, attr) \
     if (key == gc_stat_symbols[gc_stat_sym_##name]) \
-	return attr; \
+        return attr; \
     else if (hash != Qnil) \
-	rb_hash_aset(hash, gc_stat_symbols[gc_stat_sym_##name], SIZET2NUM(attr));
+        rb_hash_aset(hash, gc_stat_symbols[gc_stat_sym_##name], SIZET2NUM(attr));
 
     SET(count, objspace->profile.count);
     SET(time, (size_t) (objspace->profile.total_time_ns / (1000 * 1000) /* ns -> ms */)); // TODO: UINT64T2NUM
@@ -10823,17 +11372,17 @@ gc_stat_internal(VALUE hash_or_sym)
 #undef SET
 
     if (!NIL_P(key)) { /* matched key should return above */
-	rb_raise(rb_eArgError, "unknown key: %"PRIsVALUE, rb_sym2str(key));
+        rb_raise(rb_eArgError, "unknown key: %"PRIsVALUE, rb_sym2str(key));
     }
 
 #if defined(RGENGC_PROFILE) && RGENGC_PROFILE >= 2
     if (hash != Qnil) {
-	gc_count_add_each_types(hash, "generated_normal_object_count_types", objspace->profile.generated_normal_object_count_types);
-	gc_count_add_each_types(hash, "generated_shady_object_count_types", objspace->profile.generated_shady_object_count_types);
-	gc_count_add_each_types(hash, "shade_operation_count_types", objspace->profile.shade_operation_count_types);
-	gc_count_add_each_types(hash, "promoted_types", objspace->profile.promoted_types);
-	gc_count_add_each_types(hash, "remembered_normal_object_count_types", objspace->profile.remembered_normal_object_count_types);
-	gc_count_add_each_types(hash, "remembered_shady_object_count_types", objspace->profile.remembered_shady_object_count_types);
+        gc_count_add_each_types(hash, "generated_normal_object_count_types", objspace->profile.generated_normal_object_count_types);
+        gc_count_add_each_types(hash, "generated_shady_object_count_types", objspace->profile.generated_shady_object_count_types);
+        gc_count_add_each_types(hash, "shade_operation_count_types", objspace->profile.shade_operation_count_types);
+        gc_count_add_each_types(hash, "promoted_types", objspace->profile.promoted_types);
+        gc_count_add_each_types(hash, "remembered_normal_object_count_types", objspace->profile.remembered_normal_object_count_types);
+        gc_count_add_each_types(hash, "remembered_shady_object_count_types", objspace->profile.remembered_shady_object_count_types);
     }
 #endif
 
@@ -10865,12 +11414,12 @@ size_t
 rb_gc_stat(VALUE key)
 {
     if (SYMBOL_P(key)) {
-	size_t value = gc_stat_internal(key);
-	return value;
+        size_t value = gc_stat_internal(key);
+        return value;
     }
     else {
-	gc_stat_internal(key);
-	return 0;
+        gc_stat_internal(key);
+        return 0;
     }
 }
 
@@ -10884,6 +11433,7 @@ enum gc_stat_heap_sym {
     gc_stat_heap_sym_heap_tomb_slots,
     gc_stat_heap_sym_total_allocated_pages,
     gc_stat_heap_sym_total_freed_pages,
+    gc_stat_heap_sym_force_major_gc_count,
     gc_stat_heap_sym_last
 };
 
@@ -10902,6 +11452,7 @@ setup_gc_stat_heap_symbols(void)
         S(heap_tomb_slots);
         S(total_allocated_pages);
         S(total_freed_pages);
+        S(force_major_gc_count);
 #undef S
     }
 }
@@ -10944,6 +11495,7 @@ gc_stat_heap_internal(int size_pool_idx, VALUE hash_or_sym)
     SET(heap_tomb_slots, SIZE_POOL_TOMB_HEAP(size_pool)->total_slots);
     SET(total_allocated_pages, size_pool->total_allocated_pages);
     SET(total_freed_pages, size_pool->total_freed_pages);
+    SET(force_major_gc_count, size_pool->force_major_gc_count);
 #undef SET
 
     if (!NIL_P(key)) { /* matched key should return above */
@@ -11081,30 +11633,44 @@ gc_disable(rb_execution_context_t *ec, VALUE _)
     return rb_gc_disable();
 }
 
+#if GC_CAN_COMPILE_COMPACTION
+/*
+ *  call-seq:
+ *     GC.auto_compact = flag
+ *
+ *  Updates automatic compaction mode.
+ *
+ *  When enabled, the compactor will execute on every major collection.
+ *
+ *  Enabling compaction will degrade performance on major collections.
+ */
 static VALUE
-gc_set_auto_compact(rb_execution_context_t *ec, VALUE _, VALUE v)
+gc_set_auto_compact(VALUE _, VALUE v)
 {
-    /* If not MinGW, Windows, or does not have mmap, we cannot use mprotect for
-     * the read barrier, so we must disable automatic compaction. */
-#if !defined(__MINGW32__) && !defined(_WIN32)
-    if (!HEAP_PAGE_ALLOC_USE_MMAP) {
-        rb_raise(rb_eNotImpError, "Automatic compaction isn't available on this platform");
-    }
-#endif
-
-#if !GC_COMPACTION_SUPPORTED
-    rb_raise(rb_eNotImpError, "Automatic compaction isn't available on this platform");
-#endif
+    GC_ASSERT(GC_COMPACTION_SUPPORTED);
 
     ruby_enable_autocompact = RTEST(v);
     return v;
 }
+#else
+#  define gc_set_auto_compact rb_f_notimplement
+#endif
 
+#if GC_CAN_COMPILE_COMPACTION
+/*
+ *  call-seq:
+ *     GC.auto_compact    -> true or false
+ *
+ *  Returns whether or not automatic compaction has been enabled.
+ */
 static VALUE
-gc_get_auto_compact(rb_execution_context_t *ec, VALUE _)
+gc_get_auto_compact(VALUE _)
 {
     return RBOOL(ruby_enable_autocompact);
 }
+#else
+#  define gc_get_auto_compact rb_f_notimplement
+#endif
 
 static int
 get_envparam_size(const char *name, size_t *default_value, size_t lower_bound)
@@ -11113,53 +11679,53 @@ get_envparam_size(const char *name, size_t *default_value, size_t lower_bound)
     ssize_t val;
 
     if (ptr != NULL && *ptr) {
-	size_t unit = 0;
-	char *end;
+        size_t unit = 0;
+        char *end;
 #if SIZEOF_SIZE_T == SIZEOF_LONG_LONG
-	val = strtoll(ptr, &end, 0);
+        val = strtoll(ptr, &end, 0);
 #else
-	val = strtol(ptr, &end, 0);
-#endif
-	switch (*end) {
-	  case 'k': case 'K':
-	    unit = 1024;
-	    ++end;
-	    break;
-	  case 'm': case 'M':
-	    unit = 1024*1024;
-	    ++end;
-	    break;
-	  case 'g': case 'G':
-	    unit = 1024*1024*1024;
-	    ++end;
-	    break;
-	}
-	while (*end && isspace((unsigned char)*end)) end++;
-	if (*end) {
-	    if (RTEST(ruby_verbose)) fprintf(stderr, "invalid string for %s: %s\n", name, ptr);
-	    return 0;
-	}
-	if (unit > 0) {
-	    if (val < -(ssize_t)(SIZE_MAX / 2 / unit) || (ssize_t)(SIZE_MAX / 2 / unit) < val) {
-		if (RTEST(ruby_verbose)) fprintf(stderr, "%s=%s is ignored because it overflows\n", name, ptr);
-		return 0;
-	    }
-	    val *= unit;
-	}
-	if (val > 0 && (size_t)val > lower_bound) {
-	    if (RTEST(ruby_verbose)) {
-		fprintf(stderr, "%s=%"PRIdSIZE" (default value: %"PRIuSIZE")\n", name, val, *default_value);
-	    }
-	    *default_value = (size_t)val;
-	    return 1;
-	}
-	else {
-	    if (RTEST(ruby_verbose)) {
-		fprintf(stderr, "%s=%"PRIdSIZE" (default value: %"PRIuSIZE") is ignored because it must be greater than %"PRIuSIZE".\n",
-			name, val, *default_value, lower_bound);
-	    }
-	    return 0;
-	}
+        val = strtol(ptr, &end, 0);
+#endif
+        switch (*end) {
+          case 'k': case 'K':
+            unit = 1024;
+            ++end;
+            break;
+          case 'm': case 'M':
+            unit = 1024*1024;
+            ++end;
+            break;
+          case 'g': case 'G':
+            unit = 1024*1024*1024;
+            ++end;
+            break;
+        }
+        while (*end && isspace((unsigned char)*end)) end++;
+        if (*end) {
+            if (RTEST(ruby_verbose)) fprintf(stderr, "invalid string for %s: %s\n", name, ptr);
+            return 0;
+        }
+        if (unit > 0) {
+            if (val < -(ssize_t)(SIZE_MAX / 2 / unit) || (ssize_t)(SIZE_MAX / 2 / unit) < val) {
+                if (RTEST(ruby_verbose)) fprintf(stderr, "%s=%s is ignored because it overflows\n", name, ptr);
+                return 0;
+            }
+            val *= unit;
+        }
+        if (val > 0 && (size_t)val > lower_bound) {
+            if (RTEST(ruby_verbose)) {
+                fprintf(stderr, "%s=%"PRIdSIZE" (default value: %"PRIuSIZE")\n", name, val, *default_value);
+            }
+            *default_value = (size_t)val;
+            return 1;
+        }
+        else {
+            if (RTEST(ruby_verbose)) {
+                fprintf(stderr, "%s=%"PRIdSIZE" (default value: %"PRIuSIZE") is ignored because it must be greater than %"PRIuSIZE".\n",
+                        name, val, *default_value, lower_bound);
+            }
+            return 0;
+        }
     }
     return 0;
 }
@@ -11171,32 +11737,32 @@ get_envparam_double(const char *name, double *default_value, double lower_bound,
     double val;
 
     if (ptr != NULL && *ptr) {
-	char *end;
-	val = strtod(ptr, &end);
-	if (!*ptr || *end) {
-	    if (RTEST(ruby_verbose)) fprintf(stderr, "invalid string for %s: %s\n", name, ptr);
-	    return 0;
-	}
-
-	if (accept_zero && val == 0.0) {
-	    goto accept;
-	}
-	else if (val <= lower_bound) {
-	    if (RTEST(ruby_verbose)) {
-		fprintf(stderr, "%s=%f (default value: %f) is ignored because it must be greater than %f.\n",
-			name, val, *default_value, lower_bound);
-	    }
-	}
-	else if (upper_bound != 0.0 && /* ignore upper_bound if it is 0.0 */
-		 val > upper_bound) {
-	    if (RTEST(ruby_verbose)) {
-		fprintf(stderr, "%s=%f (default value: %f) is ignored because it must be lower than %f.\n",
-			name, val, *default_value, upper_bound);
-	    }
-	}
-	else {
+        char *end;
+        val = strtod(ptr, &end);
+        if (!*ptr || *end) {
+            if (RTEST(ruby_verbose)) fprintf(stderr, "invalid string for %s: %s\n", name, ptr);
+            return 0;
+        }
+
+        if (accept_zero && val == 0.0) {
             goto accept;
-	}
+        }
+        else if (val <= lower_bound) {
+            if (RTEST(ruby_verbose)) {
+                fprintf(stderr, "%s=%f (default value: %f) is ignored because it must be greater than %f.\n",
+                        name, val, *default_value, lower_bound);
+            }
+        }
+        else if (upper_bound != 0.0 && /* ignore upper_bound if it is 0.0 */
+                 val > upper_bound) {
+            if (RTEST(ruby_verbose)) {
+                fprintf(stderr, "%s=%f (default value: %f) is ignored because it must be lower than %f.\n",
+                        name, val, *default_value, upper_bound);
+            }
+        }
+        else {
+            goto accept;
+        }
     }
     return 0;
 
@@ -11207,24 +11773,25 @@ get_envparam_double(const char *name, double *default_value, double lower_bound,
 }
 
 static void
-gc_set_initial_pages(void)
+gc_set_initial_pages(rb_objspace_t *objspace)
 {
-    size_t min_pages;
-    rb_objspace_t *objspace = &rb_objspace;
-
     gc_rest(objspace);
 
-    min_pages = gc_params.heap_init_slots / HEAP_PAGE_OBJ_LIMIT;
-
-    size_t pages_per_class = (min_pages - heap_eden_total_pages(objspace)) / SIZE_POOL_COUNT;
-
     for (int i = 0; i < SIZE_POOL_COUNT; i++) {
         rb_size_pool_t *size_pool = &size_pools[i];
 
-        heap_add_pages(objspace, size_pool, SIZE_POOL_EDEN_HEAP(size_pool), pages_per_class);
+        if (gc_params.heap_init_slots > size_pool->eden_heap.total_slots) {
+            size_t slots = gc_params.heap_init_slots - size_pool->eden_heap.total_slots;
+            int multiple = size_pool->slot_size / BASE_SLOT_SIZE;
+            size_pool->allocatable_pages = slots * multiple / HEAP_PAGE_OBJ_LIMIT;
+        }
+        else {
+            /* We already have more slots than heap_init_slots allows, so
+             * prevent creating more pages. */
+            size_pool->allocatable_pages = 0;
+        }
     }
-
-    heap_add_pages(objspace, &size_pools[0], SIZE_POOL_EDEN_HEAP(&size_pools[0]), min_pages - heap_eden_total_pages(objspace));
+    heap_pages_expand_sorted(objspace);
 }
 
 /*
@@ -11275,26 +11842,26 @@ ruby_gc_set_params(void)
     rb_objspace_t *objspace = &rb_objspace;
     /* RUBY_GC_HEAP_FREE_SLOTS */
     if (get_envparam_size("RUBY_GC_HEAP_FREE_SLOTS", &gc_params.heap_free_slots, 0)) {
-	/* ok */
+        /* ok */
     }
 
     /* RUBY_GC_HEAP_INIT_SLOTS */
     if (get_envparam_size("RUBY_GC_HEAP_INIT_SLOTS", &gc_params.heap_init_slots, 0)) {
-	gc_set_initial_pages();
+        gc_set_initial_pages(objspace);
     }
 
     get_envparam_double("RUBY_GC_HEAP_GROWTH_FACTOR", &gc_params.growth_factor, 1.0, 0.0, FALSE);
     get_envparam_size  ("RUBY_GC_HEAP_GROWTH_MAX_SLOTS", &gc_params.growth_max_slots, 0);
     get_envparam_double("RUBY_GC_HEAP_FREE_SLOTS_MIN_RATIO", &gc_params.heap_free_slots_min_ratio,
-			0.0, 1.0, FALSE);
+                        0.0, 1.0, FALSE);
     get_envparam_double("RUBY_GC_HEAP_FREE_SLOTS_MAX_RATIO", &gc_params.heap_free_slots_max_ratio,
-			gc_params.heap_free_slots_min_ratio, 1.0, FALSE);
+                        gc_params.heap_free_slots_min_ratio, 1.0, FALSE);
     get_envparam_double("RUBY_GC_HEAP_FREE_SLOTS_GOAL_RATIO", &gc_params.heap_free_slots_goal_ratio,
-			gc_params.heap_free_slots_min_ratio, gc_params.heap_free_slots_max_ratio, TRUE);
+                        gc_params.heap_free_slots_min_ratio, gc_params.heap_free_slots_max_ratio, TRUE);
     get_envparam_double("RUBY_GC_HEAP_OLDOBJECT_LIMIT_FACTOR", &gc_params.oldobject_limit_factor, 0.0, 0.0, TRUE);
 
     if (get_envparam_size("RUBY_GC_MALLOC_LIMIT", &gc_params.malloc_limit_min, 0)) {
-	malloc_limit = gc_params.malloc_limit_min;
+        malloc_limit = gc_params.malloc_limit_min;
     }
     get_envparam_size  ("RUBY_GC_MALLOC_LIMIT_MAX", &gc_params.malloc_limit_max, 0);
     if (!gc_params.malloc_limit_max) { /* ignore max-check if 0 */
@@ -11304,7 +11871,7 @@ ruby_gc_set_params(void)
 
 #if RGENGC_ESTIMATE_OLDMALLOC
     if (get_envparam_size("RUBY_GC_OLDMALLOC_LIMIT", &gc_params.oldmalloc_limit_min, 0)) {
-	objspace->rgengc.oldmalloc_increase_limit = gc_params.oldmalloc_limit_min;
+        objspace->rgengc.oldmalloc_increase_limit = gc_params.oldmalloc_limit_min;
     }
     get_envparam_size  ("RUBY_GC_OLDMALLOC_LIMIT_MAX", &gc_params.oldmalloc_limit_max, 0);
     get_envparam_double("RUBY_GC_OLDMALLOC_LIMIT_GROWTH_FACTOR", &gc_params.oldmalloc_limit_growth_factor, 1.0, 0.0, FALSE);
@@ -11448,16 +12015,16 @@ static void
 ruby_memerror(void)
 {
     if (ruby_thread_has_gvl_p()) {
-	rb_memerror();
+        rb_memerror();
     }
     else {
-	if (ruby_native_thread_p()) {
-	    rb_thread_call_with_gvl(ruby_memerror_body, 0);
-	}
-	else {
-	    /* no ruby thread */
-	    fprintf(stderr, "[FATAL] failed to allocate memory\n");
-	}
+        if (ruby_native_thread_p()) {
+            rb_thread_call_with_gvl(ruby_memerror_body, 0);
+        }
+        else {
+            /* no ruby thread */
+            fprintf(stderr, "[FATAL] failed to allocate memory\n");
+        }
     }
     exit(EXIT_FAILURE);
 }
@@ -11482,16 +12049,16 @@ rb_memerror(void)
 
     exc = nomem_error;
     if (!exc ||
-	rb_ec_raised_p(ec, RAISED_NOMEMORY)) {
-	fprintf(stderr, "[FATAL] failed to allocate memory\n");
-	exit(EXIT_FAILURE);
+        rb_ec_raised_p(ec, RAISED_NOMEMORY)) {
+        fprintf(stderr, "[FATAL] failed to allocate memory\n");
+        exit(EXIT_FAILURE);
     }
     if (rb_ec_raised_p(ec, RAISED_NOMEMORY)) {
-	rb_ec_raised_clear(ec);
+        rb_ec_raised_clear(ec);
     }
     else {
-	rb_ec_raised_set(ec, RAISED_NOMEMORY);
-	exc = ruby_vm_special_exception_copy(exc);
+        rb_ec_raised_set(ec, RAISED_NOMEMORY);
+        exc = ruby_vm_special_exception_copy(exc);
     }
     ec->errinfo = exc;
     EC_JUMP_TAG(ec, TAG_RAISE);
@@ -11567,9 +12134,9 @@ atomic_sub_nounderflow(size_t *var, size_t sub)
     if (sub == 0) return;
 
     while (1) {
-	size_t val = *var;
-	if (val < sub) sub = val;
-	if (ATOMIC_SIZE_CAS(*var, val, val-sub) == val) break;
+        size_t val = *var;
+        if (val < sub) sub = val;
+        if (ATOMIC_SIZE_CAS(*var, val, val-sub) == val) break;
     }
 }
 
@@ -11591,11 +12158,11 @@ static inline bool
 objspace_malloc_increase_report(rb_objspace_t *objspace, void *mem, size_t new_size, size_t old_size, enum memop_type type)
 {
     if (0) fprintf(stderr, "increase - ptr: %p, type: %s, new_size: %"PRIdSIZE", old_size: %"PRIdSIZE"\n",
-		   mem,
-		   type == MEMOP_TYPE_MALLOC  ? "malloc" :
-		   type == MEMOP_TYPE_FREE    ? "free  " :
-		   type == MEMOP_TYPE_REALLOC ? "realloc": "error",
-		   new_size, old_size);
+                   mem,
+                   type == MEMOP_TYPE_MALLOC  ? "malloc" :
+                   type == MEMOP_TYPE_FREE    ? "free  " :
+                   type == MEMOP_TYPE_REALLOC ? "realloc": "error",
+                   new_size, old_size);
     return false;
 }
 
@@ -11603,62 +12170,62 @@ static bool
 objspace_malloc_increase_body(rb_objspace_t *objspace, void *mem, size_t new_size, size_t old_size, enum memop_type type)
 {
     if (new_size > old_size) {
-	ATOMIC_SIZE_ADD(malloc_increase, new_size - old_size);
+        ATOMIC_SIZE_ADD(malloc_increase, new_size - old_size);
 #if RGENGC_ESTIMATE_OLDMALLOC
-	ATOMIC_SIZE_ADD(objspace->rgengc.oldmalloc_increase, new_size - old_size);
+        ATOMIC_SIZE_ADD(objspace->rgengc.oldmalloc_increase, new_size - old_size);
 #endif
     }
     else {
-	atomic_sub_nounderflow(&malloc_increase, old_size - new_size);
+        atomic_sub_nounderflow(&malloc_increase, old_size - new_size);
 #if RGENGC_ESTIMATE_OLDMALLOC
-	atomic_sub_nounderflow(&objspace->rgengc.oldmalloc_increase, old_size - new_size);
+        atomic_sub_nounderflow(&objspace->rgengc.oldmalloc_increase, old_size - new_size);
 #endif
     }
 
     if (type == MEMOP_TYPE_MALLOC) {
       retry:
-	if (malloc_increase > malloc_limit && ruby_native_thread_p() && !dont_gc_val()) {
-	    if (ruby_thread_has_gvl_p() && is_lazy_sweeping(objspace)) {
-		gc_rest(objspace); /* gc_rest can reduce malloc_increase */
-		goto retry;
-	    }
-	    garbage_collect_with_gvl(objspace, GPR_FLAG_MALLOC);
-	}
+        if (malloc_increase > malloc_limit && ruby_native_thread_p() && !dont_gc_val()) {
+            if (ruby_thread_has_gvl_p() && is_lazy_sweeping(objspace)) {
+                gc_rest(objspace); /* gc_rest can reduce malloc_increase */
+                goto retry;
+            }
+            garbage_collect_with_gvl(objspace, GPR_FLAG_MALLOC);
+        }
     }
 
 #if MALLOC_ALLOCATED_SIZE
     if (new_size >= old_size) {
-	ATOMIC_SIZE_ADD(objspace->malloc_params.allocated_size, new_size - old_size);
+        ATOMIC_SIZE_ADD(objspace->malloc_params.allocated_size, new_size - old_size);
     }
     else {
-	size_t dec_size = old_size - new_size;
-	size_t allocated_size = objspace->malloc_params.allocated_size;
+        size_t dec_size = old_size - new_size;
+        size_t allocated_size = objspace->malloc_params.allocated_size;
 
 #if MALLOC_ALLOCATED_SIZE_CHECK
-	if (allocated_size < dec_size) {
-	    rb_bug("objspace_malloc_increase: underflow malloc_params.allocated_size.");
-	}
+        if (allocated_size < dec_size) {
+            rb_bug("objspace_malloc_increase: underflow malloc_params.allocated_size.");
+        }
 #endif
-	atomic_sub_nounderflow(&objspace->malloc_params.allocated_size, dec_size);
+        atomic_sub_nounderflow(&objspace->malloc_params.allocated_size, dec_size);
     }
 
     switch (type) {
       case MEMOP_TYPE_MALLOC:
-	ATOMIC_SIZE_INC(objspace->malloc_params.allocations);
-	break;
+        ATOMIC_SIZE_INC(objspace->malloc_params.allocations);
+        break;
       case MEMOP_TYPE_FREE:
-	{
-	    size_t allocations = objspace->malloc_params.allocations;
-	    if (allocations > 0) {
-		atomic_sub_nounderflow(&objspace->malloc_params.allocations, 1);
-	    }
+        {
+            size_t allocations = objspace->malloc_params.allocations;
+            if (allocations > 0) {
+                atomic_sub_nounderflow(&objspace->malloc_params.allocations, 1);
+            }
 #if MALLOC_ALLOCATED_SIZE_CHECK
-	    else {
-		GC_ASSERT(objspace->malloc_params.allocations > 0);
-	    }
+            else {
+                GC_ASSERT(objspace->malloc_params.allocations > 0);
+            }
 #endif
-	}
-	break;
+        }
+        break;
       case MEMOP_TYPE_REALLOC: /* ignore */ break;
     }
 #endif
@@ -11667,8 +12234,8 @@ objspace_malloc_increase_body(rb_objspace_t *objspace, void *mem, size_t new_siz
 
 #define objspace_malloc_increase(...) \
     for (bool malloc_increase_done = objspace_malloc_increase_report(__VA_ARGS__); \
-	 !malloc_increase_done; \
-	 malloc_increase_done = objspace_malloc_increase_body(__VA_ARGS__))
+         !malloc_increase_done; \
+         malloc_increase_done = objspace_malloc_increase_body(__VA_ARGS__))
 
 struct malloc_obj_info { /* 4 words */
     size_t size;
@@ -11696,6 +12263,16 @@ objspace_malloc_prepare(rb_objspace_t *objspace, size_t size)
     return size;
 }
 
+static bool
+malloc_during_gc_p(rb_objspace_t *objspace)
+{
+    /* malloc is not allowed during GC when we're not using multiple ractors
+     * (since ractors can run while another thread is sweeping) and when we
+     * have the GVL (since if we don't have the GVL, we'll try to acquire the
+     * GVL which will block and ensure the other thread finishes GC). */
+    return during_gc && !rb_multi_ractor_p() && ruby_thread_has_gvl_p();
+}
+
 static inline void *
 objspace_malloc_fixup(rb_objspace_t *objspace, void *mem, size_t size)
 {
@@ -11719,10 +12296,16 @@ objspace_malloc_fixup(rb_objspace_t *objspace, void *mem, size_t size)
 }
 
 #if defined(__GNUC__) && RUBY_DEBUG
-#define RB_BUG_INSTEAD_OF_RB_MEMERROR
+#define RB_BUG_INSTEAD_OF_RB_MEMERROR 1
 #endif
 
-#ifdef RB_BUG_INSTEAD_OF_RB_MEMERROR
+#ifndef RB_BUG_INSTEAD_OF_RB_MEMERROR
+# define RB_BUG_INSTEAD_OF_RB_MEMERROR 0
+#endif
+
+#define GC_MEMERROR(...) \
+    ((RB_BUG_INSTEAD_OF_RB_MEMERROR+0) ? rb_bug("" __VA_ARGS__) : rb_memerror())
+
 #define TRY_WITH_GC(siz, expr) do {                          \
         const gc_profile_record_flag gpr =                   \
             GPR_FLAG_FULL_MARK           |                   \
@@ -11736,29 +12319,27 @@ objspace_malloc_fixup(rb_objspace_t *objspace, void *mem, size_t size)
         }                                                    \
         else if (!garbage_collect_with_gvl(objspace, gpr)) { \
             /* @shyouhei thinks this doesn't happen */       \
-            rb_bug("TRY_WITH_GC: could not GC");             \
+            GC_MEMERROR("TRY_WITH_GC: could not GC");        \
         }                                                    \
         else if ((expr)) {                                   \
             /* Success on 2nd try */                         \
         }                                                    \
         else {                                               \
-            rb_bug("TRY_WITH_GC: could not allocate:"        \
-                   "%"PRIdSIZE" bytes for %s",               \
-                   siz, # expr);                             \
+            GC_MEMERROR("TRY_WITH_GC: could not allocate:"   \
+                        "%"PRIdSIZE" bytes for %s",          \
+                        siz, # expr);                        \
         }                                                    \
     } while (0)
-#else
-#define TRY_WITH_GC(siz, alloc) do { \
-        objspace_malloc_gc_stress(objspace); \
-	if (!(alloc) && \
-            (!garbage_collect_with_gvl(objspace, GPR_FLAG_FULL_MARK | \
-                GPR_FLAG_IMMEDIATE_MARK | GPR_FLAG_IMMEDIATE_SWEEP | \
-                GPR_FLAG_MALLOC) || \
-	     !(alloc))) { \
-	    ruby_memerror(); \
-	} \
-    } while (0)
-#endif
+
+static void
+check_malloc_not_in_gc(rb_objspace_t *objspace, const char *msg)
+{
+    if (UNLIKELY(malloc_during_gc_p(objspace))) {
+        dont_gc_on();
+        during_gc = false;
+        rb_bug("Cannot %s during GC", msg);
+    }
+}
 
 /* these shouldn't be called directly.
  * objspace_* functions do not check allocation size.
@@ -11766,6 +12347,8 @@ objspace_malloc_fixup(rb_objspace_t *objspace, void *mem, size_t size)
 static void *
 objspace_xmalloc0(rb_objspace_t *objspace, size_t size)
 {
+    check_malloc_not_in_gc(objspace, "malloc");
+
     void *mem;
 
     size = objspace_malloc_prepare(objspace, size);
@@ -11783,6 +12366,8 @@ xmalloc2_size(const size_t count, const size_t elsize)
 static void *
 objspace_xrealloc(rb_objspace_t *objspace, void *ptr, size_t new_size, size_t old_size)
 {
+    check_malloc_not_in_gc(objspace, "realloc");
+
     void *mem;
 
     if (!ptr) return objspace_xmalloc0(objspace, new_size);
@@ -11840,7 +12425,7 @@ objspace_xrealloc(rb_objspace_t *objspace, void *ptr, size_t new_size, size_t ol
 #endif
 
     old_size = objspace_malloc_size(objspace, ptr, old_size);
-    TRY_WITH_GC(new_size, mem = realloc(ptr, new_size));
+    TRY_WITH_GC(new_size, mem = RB_GNUC_EXTENSION_BLOCK(realloc(ptr, new_size)));
     new_size = objspace_malloc_size(objspace, mem, new_size);
 
 #if CALC_EXACT_MALLOC_SIZE
@@ -11982,8 +12567,9 @@ objspace_xfree(rb_objspace_t *objspace, void *ptr, size_t old_size)
     old_size = objspace_malloc_size(objspace, ptr, old_size);
 
     objspace_malloc_increase(objspace, ptr, 0, old_size, MEMOP_TYPE_FREE) {
-	free(ptr);
-	RB_DEBUG_COUNTER_INC(heap_xfree);
+        free(ptr);
+        ptr = NULL;
+        RB_DEBUG_COUNTER_INC(heap_xfree);
     }
 }
 
@@ -11997,7 +12583,7 @@ void *
 ruby_xmalloc_body(size_t size)
 {
     if ((ssize_t)size < 0) {
-	negative_size_allocation_error("too large allocation size");
+        negative_size_allocation_error("too large allocation size");
     }
     return ruby_xmalloc0(size);
 }
@@ -12006,8 +12592,8 @@ void
 ruby_malloc_size_overflow(size_t count, size_t elsize)
 {
     rb_raise(rb_eArgError,
-	     "malloc: possible integer overflow (%"PRIuSIZE"*%"PRIuSIZE")",
-	     count, elsize);
+             "malloc: possible integer overflow (%"PRIuSIZE"*%"PRIuSIZE")",
+             count, elsize);
 }
 
 void *
@@ -12019,6 +12605,13 @@ ruby_xmalloc2_body(size_t n, size_t size)
 static void *
 objspace_xcalloc(rb_objspace_t *objspace, size_t size)
 {
+    if (UNLIKELY(malloc_during_gc_p(objspace))) {
+        rb_warn("calloc during GC detected, this could cause crashes if it triggers another GC");
+#if RGENGC_CHECK_MODE || RUBY_DEBUG
+        rb_bug("Cannot calloc during GC");
+#endif
+    }
+
     void *mem;
 
     size = objspace_malloc_prepare(objspace, size);
@@ -12039,7 +12632,7 @@ void *
 ruby_sized_xrealloc(void *ptr, size_t new_size, size_t old_size)
 {
     if ((ssize_t)new_size < 0) {
-	negative_size_allocation_error("too large allocation size");
+        negative_size_allocation_error("too large allocation size");
     }
 
     return objspace_xrealloc(&rb_objspace, ptr, new_size, old_size);
@@ -12073,8 +12666,16 @@ ruby_xrealloc2_body(void *ptr, size_t n, size_t size)
 void
 ruby_sized_xfree(void *x, size_t size)
 {
-    if (x) {
-	objspace_xfree(&rb_objspace, x, size);
+    if (LIKELY(x)) {
+        /* It's possible for a C extension's pthread destructor function set by pthread_key_create
+         * to be called after ruby_vm_destruct and attempt to free memory. Fall back to mimfree in
+         * that case. */
+        if (LIKELY(GET_VM())) {
+            objspace_xfree(&rb_objspace, x, size);
+        }
+        else {
+            ruby_mimfree(x);
+        }
     }
 }
 
@@ -12184,7 +12785,7 @@ rb_alloc_tmp_buffer(volatile VALUE *store, long len)
     long cnt;
 
     if (len < 0 || (cnt = (long)roomof(len, sizeof(VALUE))) < 0) {
-	rb_raise(rb_eArgError, "negative buffer size (or size too big)");
+        rb_raise(rb_eArgError, "negative buffer size (or size too big)");
     }
 
     return rb_alloc_tmp_buffer_with_count(store, len, cnt);
@@ -12195,9 +12796,9 @@ rb_free_tmp_buffer(volatile VALUE *store)
 {
     rb_imemo_tmpbuf_t *s = (rb_imemo_tmpbuf_t*)ATOMIC_VALUE_EXCHANGE(*store, 0);
     if (s) {
-	void *ptr = ATOMIC_PTR_EXCHANGE(s->ptr, 0);
-	s->cnt = 0;
-	ruby_xfree(ptr);
+        void *ptr = ATOMIC_PTR_EXCHANGE(s->ptr, 0);
+        s->cnt = 0;
+        ruby_xfree(ptr);
     }
 }
 
@@ -12238,10 +12839,10 @@ rb_gc_adjust_memory_usage(ssize_t diff)
 {
     rb_objspace_t *objspace = &rb_objspace;
     if (diff > 0) {
-	objspace_malloc_increase(objspace, 0, diff, 0, MEMOP_TYPE_REALLOC);
+        objspace_malloc_increase(objspace, 0, diff, 0, MEMOP_TYPE_REALLOC);
     }
     else if (diff < 0) {
-	objspace_malloc_increase(objspace, 0, 0, -diff, MEMOP_TYPE_REALLOC);
+        objspace_malloc_increase(objspace, 0, 0, -diff, MEMOP_TYPE_REALLOC);
     }
 }
 
@@ -12268,12 +12869,47 @@ wmap_mark_map(st_data_t key, st_data_t val, st_data_t arg)
 }
 #endif
 
+static int
+wmap_replace_ref(st_data_t *key, st_data_t *value, st_data_t _argp, int existing)
+{
+    *key = rb_gc_location((VALUE)*key);
+
+    VALUE *values = (VALUE *)*value;
+    VALUE size = values[0];
+
+    for (VALUE index = 1; index <= size; index++) {
+        values[index] = rb_gc_location(values[index]);
+    }
+
+    return ST_CONTINUE;
+}
+
+static int
+wmap_foreach_replace(st_data_t key, st_data_t value, st_data_t _argp, int error)
+{
+    if (rb_gc_location((VALUE)key) != (VALUE)key) {
+        return ST_REPLACE;
+    }
+
+    VALUE *values = (VALUE *)value;
+    VALUE size = values[0];
+
+    for (VALUE index = 1; index <= size; index++) {
+        VALUE val = values[index];
+        if (rb_gc_location(val) != val) {
+            return ST_REPLACE;
+        }
+    }
+
+    return ST_CONTINUE;
+}
+
 static void
 wmap_compact(void *ptr)
 {
     struct weakmap *w = ptr;
     if (w->wmap2obj) rb_gc_update_tbl_refs(w->wmap2obj);
-    if (w->obj2wmap) rb_gc_update_tbl_refs(w->obj2wmap);
+    if (w->obj2wmap) st_foreach_with_replace(w->obj2wmap, wmap_foreach_replace, wmap_replace_ref, (st_data_t)NULL);
     w->final = rb_gc_location(w->final);
 }
 
@@ -12302,6 +12938,7 @@ wmap_free(void *ptr)
     st_foreach(w->obj2wmap, wmap_free_map, 0);
     st_free_table(w->obj2wmap);
     st_free_table(w->wmap2obj);
+    xfree(w);
 }
 
 static int
@@ -12327,9 +12964,9 @@ wmap_memsize(const void *ptr)
 static const rb_data_type_t weakmap_type = {
     "weakmap",
     {
-	wmap_mark,
-	wmap_free,
-	wmap_memsize,
+        wmap_mark,
+        wmap_free,
+        wmap_memsize,
         wmap_compact,
     },
     0, 0, RUBY_TYPED_FREE_IMMEDIATELY
@@ -12352,42 +12989,58 @@ static int
 wmap_live_p(rb_objspace_t *objspace, VALUE obj)
 {
     if (SPECIAL_CONST_P(obj)) return TRUE;
-    if (is_pointer_to_heap(objspace, (void *)obj)) {
-        void *poisoned = asan_unpoison_object_temporary(obj);
+    /* If is_pointer_to_heap returns false, the page could be in the tomb heap
+     * or have already been freed. */
+    if (!is_pointer_to_heap(objspace, (void *)obj)) return FALSE;
 
-        enum ruby_value_type t = BUILTIN_TYPE(obj);
-        int ret = (!(t == T_NONE || t >= T_FIXNUM || t == T_ICLASS) &&
-                   is_live_object(objspace, obj));
+    void *poisoned = asan_unpoison_object_temporary(obj);
 
-        if (poisoned) {
-            asan_poison_object(obj);
-        }
+    enum ruby_value_type t = BUILTIN_TYPE(obj);
+    int ret = (!(t == T_NONE || t >= T_FIXNUM || t == T_ICLASS) &&
+                is_live_object(objspace, obj));
 
-        return ret;
+    if (poisoned) {
+        asan_poison_object(obj);
     }
-    return TRUE;
+
+    return ret;
 }
 
 static int
-wmap_final_func(st_data_t *key, st_data_t *value, st_data_t arg, int existing)
+wmap_remove_inverse_ref(st_data_t *key, st_data_t *val, st_data_t arg, int existing)
 {
-    VALUE wmap, *ptr, size, i, j;
     if (!existing) return ST_STOP;
-    wmap = (VALUE)arg, ptr = (VALUE *)*value;
-    for (i = j = 1, size = ptr[0]; i <= size; ++i) {
-	if (ptr[i] != wmap) {
-	    ptr[j++] = ptr[i];
-	}
+
+    VALUE old_ref = (VALUE)arg;
+
+    VALUE *values = (VALUE *)*val;
+    VALUE size = values[0];
+
+    if (size == 1) {
+        // fast path, we only had one backref
+        RUBY_ASSERT(values[1] == old_ref);
+        ruby_sized_xfree(values, 2 * sizeof(VALUE));
+        return ST_DELETE;
     }
-    if (j == 1) {
-	ruby_sized_xfree(ptr, i * sizeof(VALUE));
-	return ST_DELETE;
+
+    bool found = false;
+    VALUE index = 1;
+    for (; index <= size; index++) {
+        if (values[index] == old_ref) {
+            found = true;
+            break;
+        }
     }
-    if (j < i) {
-        SIZED_REALLOC_N(ptr, VALUE, j + 1, i);
-	ptr[0] = j;
-	*value = (st_data_t)ptr;
+    if (!found) return ST_STOP;
+
+    if (size > index) {
+        MEMMOVE(&values[index], &values[index + 1], VALUE, size - index);
     }
+
+    size -= 1;
+    values[0] = size;
+    SIZED_REALLOC_N(values, VALUE, size + 1, size + 2);
+    *val = (st_data_t)values;
     return ST_CONTINUE;
 }
 
@@ -12401,26 +13054,26 @@ wmap_finalize(RB_BLOCK_CALL_FUNC_ARGLIST(objid, self))
 
     TypedData_Get_Struct(self, struct weakmap, &weakmap_type, w);
     /* Get reference from object id. */
-    if ((obj = id2ref_obj_tbl(&rb_objspace, objid)) == Qundef) {
+    if (UNDEF_P(obj = id2ref_obj_tbl(&rb_objspace, objid))) {
         rb_bug("wmap_finalize: objid is not found.");
     }
 
     /* obj is original referenced object and/or weak reference. */
     orig = (st_data_t)obj;
     if (st_delete(w->obj2wmap, &orig, &data)) {
-	rids = (VALUE *)data;
-	size = *rids++;
-	for (i = 0; i < size; ++i) {
-	    wmap = (st_data_t)rids[i];
-	    st_delete(w->wmap2obj, &wmap, NULL);
-	}
-	ruby_sized_xfree((VALUE *)data, (size + 1) * sizeof(VALUE));
+        rids = (VALUE *)data;
+        size = *rids++;
+        for (i = 0; i < size; ++i) {
+            wmap = (st_data_t)rids[i];
+            st_delete(w->wmap2obj, &wmap, NULL);
+        }
+        ruby_sized_xfree((VALUE *)data, (size + 1) * sizeof(VALUE));
     }
 
     wmap = (st_data_t)obj;
     if (st_delete(w->wmap2obj, &wmap, &orig)) {
-	wmap = (st_data_t)obj;
-	st_update(w->obj2wmap, orig, wmap_final_func, wmap);
+        wmap = (st_data_t)obj;
+        st_update(w->obj2wmap, orig, wmap_remove_inverse_ref, wmap);
     }
     return self;
 }
@@ -12453,11 +13106,11 @@ wmap_inspect_i(st_data_t key, st_data_t val, st_data_t arg)
     VALUE k = (VALUE)key, v = (VALUE)val;
 
     if (RSTRING_PTR(str)[0] == '#') {
-	rb_str_cat2(str, ", ");
+        rb_str_cat2(str, ", ");
     }
     else {
-	rb_str_cat2(str, ": ");
-	RSTRING_PTR(str)[0] = '#';
+        rb_str_cat2(str, ": ");
+        RSTRING_PTR(str)[0] = '#';
     }
     wmap_inspect_append(objspace, str, k);
     rb_str_cat2(str, " => ");
@@ -12477,9 +13130,9 @@ wmap_inspect(VALUE self)
     TypedData_Get_Struct(self, struct weakmap, &weakmap_type, w);
     str = rb_sprintf("-<%"PRIsVALUE":%p", c, (void *)self);
     if (w->wmap2obj) {
-	args.objspace = &rb_objspace;
-	args.value = str;
-	st_foreach(w->wmap2obj, wmap_inspect_i, (st_data_t)&args);
+        args.objspace = &rb_objspace;
+        args.value = str;
+        st_foreach(w->wmap2obj, wmap_inspect_i, (st_data_t)&args);
     }
     RSTRING_PTR(str)[0] = '#';
     rb_str_cat2(str, ">");
@@ -12635,14 +13288,22 @@ wmap_aset_update(st_data_t *key, st_data_t *val, st_data_t arg, int existing)
 {
     VALUE size, *ptr, *optr;
     if (existing) {
-	size = (ptr = optr = (VALUE *)*val)[0];
-	++size;
+        size = (ptr = optr = (VALUE *)*val)[0];
+
+        for (VALUE index = 1; index <= size; index++) {
+            if (ptr[index] == (VALUE)arg) {
+                // The reference was already registered.
+                return ST_STOP;
+            }
+        }
+
+        ++size;
         SIZED_REALLOC_N(ptr, VALUE, size + 1, size);
     }
     else {
-	optr = 0;
-	size = 1;
-	ptr = ruby_xmalloc0(2 * sizeof(VALUE));
+        optr = 0;
+        size = 1;
+        ptr = ruby_xmalloc0(2 * sizeof(VALUE));
     }
     ptr[0] = size;
     ptr[size] = (VALUE)arg;
@@ -12651,6 +13312,23 @@ wmap_aset_update(st_data_t *key, st_data_t *val, st_data_t arg, int existing)
     return ST_CONTINUE;
 }
 
+struct wmap_aset_replace_args {
+    VALUE new_value;
+    VALUE old_value;
+};
+
+static int
+wmap_aset_replace_value(st_data_t *key, st_data_t *val, st_data_t _args, int existing)
+{
+    struct wmap_aset_replace_args *args = (struct wmap_aset_replace_args *)_args;
+
+    if (existing) {
+        args->old_value = *val;
+    }
+    *val = (st_data_t)args->new_value;
+    return ST_CONTINUE;
+}
+
 /* Creates a weak reference from the given key to the given value */
 static VALUE
 wmap_aset(VALUE self, VALUE key, VALUE value)
@@ -12665,8 +13343,25 @@ wmap_aset(VALUE self, VALUE key, VALUE value)
         define_final0(key, w->final);
     }
 
-    st_update(w->obj2wmap, (st_data_t)value, wmap_aset_update, key);
-    st_insert(w->wmap2obj, (st_data_t)key, (st_data_t)value);
+    struct wmap_aset_replace_args aset_args = {
+        .new_value = value,
+        .old_value = Qundef,
+    };
+    st_update(w->wmap2obj, (st_data_t)key, wmap_aset_replace_value, (st_data_t)&aset_args);
+
+    // If the value is unchanged, we have nothing to do.
+    if (value != aset_args.old_value) {
+        if (!UNDEF_P(aset_args.old_value) && FL_ABLE(aset_args.old_value)) {
+            // That key existed and had an inverse reference, we need to clear the outdated inverse reference.
+            st_update(w->obj2wmap, (st_data_t)aset_args.old_value, wmap_remove_inverse_ref, key);
+        }
+
+        if (FL_ABLE(value)) {
+            // If the value has no finalizer, we don't need to keep the inverse reference
+            st_update(w->obj2wmap, (st_data_t)value, wmap_aset_update, key);
+        }
+    }
+
     return nonspecial_obj_id(value);
 }
 
@@ -12692,14 +13387,14 @@ static VALUE
 wmap_aref(VALUE self, VALUE key)
 {
     VALUE obj = wmap_lookup(self, key);
-    return obj != Qundef ? obj : Qnil;
+    return !UNDEF_P(obj) ? obj : Qnil;
 }
 
 /* Returns +true+ if +key+ is registered */
 static VALUE
 wmap_has_key(VALUE self, VALUE key)
 {
-    return RBOOL(wmap_lookup(self, key) != Qundef);
+    return RBOOL(!UNDEF_P(wmap_lookup(self, key)));
 }
 
 /* Returns the number of referenced objects */
@@ -12754,17 +13449,17 @@ current_process_time(struct timespec *ts)
 
 #ifdef _WIN32
     {
-	FILETIME creation_time, exit_time, kernel_time, user_time;
+        FILETIME creation_time, exit_time, kernel_time, user_time;
         ULARGE_INTEGER ui;
 
         if (GetProcessTimes(GetCurrentProcess(),
-			    &creation_time, &exit_time, &kernel_time, &user_time) != 0) {
+                            &creation_time, &exit_time, &kernel_time, &user_time) != 0) {
             memcpy(&ui, &user_time, sizeof(FILETIME));
 #define PER100NSEC (uint64_t)(1000 * 1000 * 10)
             ts->tv_nsec = (long)(ui.QuadPart % PER100NSEC);
             ts->tv_sec  = (time_t)(ui.QuadPart / PER100NSEC);
             return true;
-	}
+        }
     }
 #endif
 
@@ -12788,44 +13483,44 @@ static inline void
 gc_prof_setup_new_record(rb_objspace_t *objspace, unsigned int reason)
 {
     if (objspace->profile.run) {
-	size_t index = objspace->profile.next_index;
-	gc_profile_record *record;
-
-	/* create new record */
-	objspace->profile.next_index++;
-
-	if (!objspace->profile.records) {
-	    objspace->profile.size = GC_PROFILE_RECORD_DEFAULT_SIZE;
-	    objspace->profile.records = malloc(xmalloc2_size(sizeof(gc_profile_record), objspace->profile.size));
-	}
-	if (index >= objspace->profile.size) {
-	    void *ptr;
-	    objspace->profile.size += 1000;
-	    ptr = realloc(objspace->profile.records, xmalloc2_size(sizeof(gc_profile_record), objspace->profile.size));
-	    if (!ptr) rb_memerror();
-	    objspace->profile.records = ptr;
-	}
-	if (!objspace->profile.records) {
-	    rb_bug("gc_profile malloc or realloc miss");
-	}
-	record = objspace->profile.current_record = &objspace->profile.records[objspace->profile.next_index - 1];
-	MEMZERO(record, gc_profile_record, 1);
-
-	/* setup before-GC parameter */
-	record->flags = reason | (ruby_gc_stressful ? GPR_FLAG_STRESS : 0);
+        size_t index = objspace->profile.next_index;
+        gc_profile_record *record;
+
+        /* create new record */
+        objspace->profile.next_index++;
+
+        if (!objspace->profile.records) {
+            objspace->profile.size = GC_PROFILE_RECORD_DEFAULT_SIZE;
+            objspace->profile.records = malloc(xmalloc2_size(sizeof(gc_profile_record), objspace->profile.size));
+        }
+        if (index >= objspace->profile.size) {
+            void *ptr;
+            objspace->profile.size += 1000;
+            ptr = realloc(objspace->profile.records, xmalloc2_size(sizeof(gc_profile_record), objspace->profile.size));
+            if (!ptr) rb_memerror();
+            objspace->profile.records = ptr;
+        }
+        if (!objspace->profile.records) {
+            rb_bug("gc_profile malloc or realloc miss");
+        }
+        record = objspace->profile.current_record = &objspace->profile.records[objspace->profile.next_index - 1];
+        MEMZERO(record, gc_profile_record, 1);
+
+        /* setup before-GC parameter */
+        record->flags = reason | (ruby_gc_stressful ? GPR_FLAG_STRESS : 0);
 #if MALLOC_ALLOCATED_SIZE
-	record->allocated_size = malloc_allocated_size;
+        record->allocated_size = malloc_allocated_size;
 #endif
 #if GC_PROFILE_MORE_DETAIL && GC_PROFILE_DETAIL_MEMORY
 #ifdef RUSAGE_SELF
-	{
-	    struct rusage usage;
-	    if (getrusage(RUSAGE_SELF, &usage) == 0) {
-		record->maxrss = usage.ru_maxrss;
-		record->minflt = usage.ru_minflt;
-		record->majflt = usage.ru_majflt;
-	    }
-	}
+        {
+            struct rusage usage;
+            if (getrusage(RUSAGE_SELF, &usage) == 0) {
+                record->maxrss = usage.ru_maxrss;
+                record->minflt = usage.ru_minflt;
+                record->majflt = usage.ru_majflt;
+            }
+        }
 #endif
 #endif
     }
@@ -12835,12 +13530,12 @@ static inline void
 gc_prof_timer_start(rb_objspace_t *objspace)
 {
     if (gc_prof_enabled(objspace)) {
-	gc_profile_record *record = gc_prof_record(objspace);
+        gc_profile_record *record = gc_prof_record(objspace);
 #if GC_PROFILE_MORE_DETAIL
-	record->prepare_time = objspace->profile.prepare_time;
+        record->prepare_time = objspace->profile.prepare_time;
 #endif
-	record->gc_time = 0;
-	record->gc_invoke_time = getrusage_time();
+        record->gc_time = 0;
+        record->gc_invoke_time = getrusage_time();
     }
 }
 
@@ -12849,10 +13544,10 @@ elapsed_time_from(double time)
 {
     double now = getrusage_time();
     if (now > time) {
-	return now - time;
+        return now - time;
     }
     else {
-	return 0;
+        return 0;
     }
 }
 
@@ -12860,9 +13555,9 @@ static inline void
 gc_prof_timer_stop(rb_objspace_t *objspace)
 {
     if (gc_prof_enabled(objspace)) {
-	gc_profile_record *record = gc_prof_record(objspace);
-	record->gc_time = elapsed_time_from(record->gc_invoke_time);
-	record->gc_invoke_time -= objspace->profile.invoke_time;
+        gc_profile_record *record = gc_prof_record(objspace);
+        record->gc_time = elapsed_time_from(record->gc_invoke_time);
+        record->gc_invoke_time -= objspace->profile.invoke_time;
     }
 }
 
@@ -12874,7 +13569,7 @@ gc_prof_mark_timer_start(rb_objspace_t *objspace)
     RUBY_DTRACE_GC_HOOK(MARK_BEGIN);
 #if GC_PROFILE_MORE_DETAIL
     if (gc_prof_enabled(objspace)) {
-	gc_prof_record(objspace)->gc_mark_time = getrusage_time();
+        gc_prof_record(objspace)->gc_mark_time = getrusage_time();
     }
 #endif
 }
@@ -12886,7 +13581,7 @@ gc_prof_mark_timer_stop(rb_objspace_t *objspace)
 #if GC_PROFILE_MORE_DETAIL
     if (gc_prof_enabled(objspace)) {
         gc_profile_record *record = gc_prof_record(objspace);
-	record->gc_mark_time = elapsed_time_from(record->gc_mark_time);
+        record->gc_mark_time = elapsed_time_from(record->gc_mark_time);
     }
 #endif
 }
@@ -12896,11 +13591,11 @@ gc_prof_sweep_timer_start(rb_objspace_t *objspace)
 {
     RUBY_DTRACE_GC_HOOK(SWEEP_BEGIN);
     if (gc_prof_enabled(objspace)) {
-	gc_profile_record *record = gc_prof_record(objspace);
+        gc_profile_record *record = gc_prof_record(objspace);
 
-	if (record->gc_time > 0 || GC_PROFILE_MORE_DETAIL) {
-	    objspace->profile.gc_sweep_start_time = getrusage_time();
-	}
+        if (record->gc_time > 0 || GC_PROFILE_MORE_DETAIL) {
+            objspace->profile.gc_sweep_start_time = getrusage_time();
+        }
     }
 }
 
@@ -12910,23 +13605,23 @@ gc_prof_sweep_timer_stop(rb_objspace_t *objspace)
     RUBY_DTRACE_GC_HOOK(SWEEP_END);
 
     if (gc_prof_enabled(objspace)) {
-	double sweep_time;
-	gc_profile_record *record = gc_prof_record(objspace);
-
-	if (record->gc_time > 0) {
-	    sweep_time = elapsed_time_from(objspace->profile.gc_sweep_start_time);
-	    /* need to accumulate GC time for lazy sweep after gc() */
-	    record->gc_time += sweep_time;
-	}
-	else if (GC_PROFILE_MORE_DETAIL) {
-	    sweep_time = elapsed_time_from(objspace->profile.gc_sweep_start_time);
-	}
+        double sweep_time;
+        gc_profile_record *record = gc_prof_record(objspace);
+
+        if (record->gc_time > 0) {
+            sweep_time = elapsed_time_from(objspace->profile.gc_sweep_start_time);
+            /* need to accumulate GC time for lazy sweep after gc() */
+            record->gc_time += sweep_time;
+        }
+        else if (GC_PROFILE_MORE_DETAIL) {
+            sweep_time = elapsed_time_from(objspace->profile.gc_sweep_start_time);
+        }
 
 #if GC_PROFILE_MORE_DETAIL
-	record->gc_sweep_time += sweep_time;
-	if (heap_pages_deferred_final) record->flags |= GPR_FLAG_HAVE_FINALIZE;
+        record->gc_sweep_time += sweep_time;
+        if (heap_pages_deferred_final) record->flags |= GPR_FLAG_HAVE_FINALIZE;
 #endif
-	if (heap_pages_deferred_final) objspace->profile.latest_gc_info |= GPR_FLAG_HAVE_FINALIZE;
+        if (heap_pages_deferred_final) objspace->profile.latest_gc_info |= GPR_FLAG_HAVE_FINALIZE;
     }
 }
 
@@ -12936,8 +13631,8 @@ gc_prof_set_malloc_info(rb_objspace_t *objspace)
 #if GC_PROFILE_MORE_DETAIL
     if (gc_prof_enabled(objspace)) {
         gc_profile_record *record = gc_prof_record(objspace);
-	record->allocate_increase = malloc_increase;
-	record->allocate_limit = malloc_limit;
+        record->allocate_increase = malloc_increase;
+        record->allocate_limit = malloc_limit;
     }
 #endif
 }
@@ -12946,19 +13641,19 @@ static inline void
 gc_prof_set_heap_info(rb_objspace_t *objspace)
 {
     if (gc_prof_enabled(objspace)) {
-	gc_profile_record *record = gc_prof_record(objspace);
-	size_t live = objspace->profile.total_allocated_objects_at_gc_start - objspace->profile.total_freed_objects;
-	size_t total = objspace->profile.heap_used_at_gc_start * HEAP_PAGE_OBJ_LIMIT;
+        gc_profile_record *record = gc_prof_record(objspace);
+        size_t live = objspace->profile.total_allocated_objects_at_gc_start - objspace->profile.total_freed_objects;
+        size_t total = objspace->profile.heap_used_at_gc_start * HEAP_PAGE_OBJ_LIMIT;
 
 #if GC_PROFILE_MORE_DETAIL
-	record->heap_use_pages = objspace->profile.heap_used_at_gc_start;
-	record->heap_live_objects = live;
-	record->heap_free_objects = total - live;
+        record->heap_use_pages = objspace->profile.heap_used_at_gc_start;
+        record->heap_live_objects = live;
+        record->heap_free_objects = total - live;
 #endif
 
-	record->heap_total_objects = total;
-	record->heap_use_size = live * sizeof(RVALUE);
-	record->heap_total_size = total * sizeof(RVALUE);
+        record->heap_total_objects = total;
+        record->heap_use_size = live * sizeof(RVALUE);
+        record->heap_total_size = total * sizeof(RVALUE);
     }
 }
 
@@ -12966,7 +13661,7 @@ gc_prof_set_heap_info(rb_objspace_t *objspace)
  *  call-seq:
  *    GC::Profiler.clear          -> nil
  *
- *  Clears the GC profiler data.
+ *  Clears the \GC profiler data.
  *
  */
 
@@ -13044,14 +13739,14 @@ gc_profile_record_get(VALUE _)
     rb_objspace_t *objspace = (&rb_objspace);
 
     if (!objspace->profile.run) {
-	return Qnil;
+        return Qnil;
     }
 
     for (i =0; i < objspace->profile.next_index; i++) {
-	gc_profile_record *record = &objspace->profile.records[i];
+        gc_profile_record *record = &objspace->profile.records[i];
 
-	prof = rb_hash_new();
-	rb_hash_aset(prof, ID2SYM(rb_intern("GC_FLAGS")), gc_info_decode(0, rb_hash_new(), record->flags));
+        prof = rb_hash_new();
+        rb_hash_aset(prof, ID2SYM(rb_intern("GC_FLAGS")), gc_info_decode(0, rb_hash_new(), record->flags));
         rb_hash_aset(prof, ID2SYM(rb_intern("GC_TIME")), DBL2NUM(record->gc_time));
         rb_hash_aset(prof, ID2SYM(rb_intern("GC_INVOKE_TIME")), DBL2NUM(record->gc_invoke_time));
         rb_hash_aset(prof, ID2SYM(rb_intern("HEAP_USE_SIZE")), SIZET2NUM(record->heap_use_size));
@@ -13068,18 +13763,18 @@ gc_profile_record_get(VALUE _)
         rb_hash_aset(prof, ID2SYM(rb_intern("HEAP_LIVE_OBJECTS")), SIZET2NUM(record->heap_live_objects));
         rb_hash_aset(prof, ID2SYM(rb_intern("HEAP_FREE_OBJECTS")), SIZET2NUM(record->heap_free_objects));
 
-	rb_hash_aset(prof, ID2SYM(rb_intern("REMOVING_OBJECTS")), SIZET2NUM(record->removing_objects));
-	rb_hash_aset(prof, ID2SYM(rb_intern("EMPTY_OBJECTS")), SIZET2NUM(record->empty_objects));
+        rb_hash_aset(prof, ID2SYM(rb_intern("REMOVING_OBJECTS")), SIZET2NUM(record->removing_objects));
+        rb_hash_aset(prof, ID2SYM(rb_intern("EMPTY_OBJECTS")), SIZET2NUM(record->empty_objects));
 
-	rb_hash_aset(prof, ID2SYM(rb_intern("HAVE_FINALIZE")), RBOOL(record->flags & GPR_FLAG_HAVE_FINALIZE));
+        rb_hash_aset(prof, ID2SYM(rb_intern("HAVE_FINALIZE")), RBOOL(record->flags & GPR_FLAG_HAVE_FINALIZE));
 #endif
 
 #if RGENGC_PROFILE > 0
-	rb_hash_aset(prof, ID2SYM(rb_intern("OLD_OBJECTS")), SIZET2NUM(record->old_objects));
-	rb_hash_aset(prof, ID2SYM(rb_intern("REMEMBERED_NORMAL_OBJECTS")), SIZET2NUM(record->remembered_normal_objects));
-	rb_hash_aset(prof, ID2SYM(rb_intern("REMEMBERED_SHADY_OBJECTS")), SIZET2NUM(record->remembered_shady_objects));
+        rb_hash_aset(prof, ID2SYM(rb_intern("OLD_OBJECTS")), SIZET2NUM(record->old_objects));
+        rb_hash_aset(prof, ID2SYM(rb_intern("REMEMBERED_NORMAL_OBJECTS")), SIZET2NUM(record->remembered_normal_objects));
+        rb_hash_aset(prof, ID2SYM(rb_intern("REMEMBERED_SHADY_OBJECTS")), SIZET2NUM(record->remembered_shady_objects));
 #endif
-	rb_ary_push(gc_profile, prof);
+        rb_ary_push(gc_profile, prof);
     }
 
     return gc_profile;
@@ -13095,8 +13790,8 @@ gc_profile_dump_major_reason(unsigned int flags, char *buff)
     int i = 0;
 
     if (reason == GPR_FLAG_NONE) {
-	buff[0] = '-';
-	buff[1] = 0;
+        buff[0] = '-';
+        buff[1] = 0;
     }
     else {
 #define C(x, s) \
@@ -13105,11 +13800,11 @@ gc_profile_dump_major_reason(unsigned int flags, char *buff)
       if (i >= MAJOR_REASON_MAX) rb_bug("gc_profile_dump_major_reason: overflow"); \
       buff[i] = 0; \
   }
-	C(NOFREE, N);
-	C(OLDGEN, O);
-	C(SHADY,  S);
+        C(NOFREE, N);
+        C(OLDGEN, O);
+        C(SHADY,  S);
 #if RGENGC_ESTIMATE_OLDMALLOC
-	C(OLDMALLOC, M);
+        C(OLDMALLOC, M);
 #endif
 #undef C
     }
@@ -13127,88 +13822,88 @@ gc_profile_dump_on(VALUE out, VALUE (*append)(VALUE, VALUE))
 #endif
 
     if (objspace->profile.run && count /* > 1 */) {
-	size_t i;
-	const gc_profile_record *record;
+        size_t i;
+        const gc_profile_record *record;
 
-	append(out, rb_sprintf("GC %"PRIuSIZE" invokes.\n", objspace->profile.count));
-	append(out, rb_str_new_cstr("Index    Invoke Time(sec)       Use Size(byte)     Total Size(byte)         Total Object                    GC Time(ms)\n"));
+        append(out, rb_sprintf("GC %"PRIuSIZE" invokes.\n", objspace->profile.count));
+        append(out, rb_str_new_cstr("Index    Invoke Time(sec)       Use Size(byte)     Total Size(byte)         Total Object                    GC Time(ms)\n"));
 
-	for (i = 0; i < count; i++) {
-	    record = &objspace->profile.records[i];
-	    append(out, rb_sprintf("%5"PRIuSIZE" %19.3f %20"PRIuSIZE" %20"PRIuSIZE" %20"PRIuSIZE" %30.20f\n",
-				   i+1, record->gc_invoke_time, record->heap_use_size,
-				   record->heap_total_size, record->heap_total_objects, record->gc_time*1000));
-	}
+        for (i = 0; i < count; i++) {
+            record = &objspace->profile.records[i];
+            append(out, rb_sprintf("%5"PRIuSIZE" %19.3f %20"PRIuSIZE" %20"PRIuSIZE" %20"PRIuSIZE" %30.20f\n",
+                                   i+1, record->gc_invoke_time, record->heap_use_size,
+                                   record->heap_total_size, record->heap_total_objects, record->gc_time*1000));
+        }
 
 #if GC_PROFILE_MORE_DETAIL
         const char *str = "\n\n" \
-				    "More detail.\n" \
-				    "Prepare Time = Previously GC's rest sweep time\n"
-				    "Index Flags          Allocate Inc.  Allocate Limit"
+                                    "More detail.\n" \
+                                    "Prepare Time = Previously GC's rest sweep time\n"
+                                    "Index Flags          Allocate Inc.  Allocate Limit"
 #if CALC_EXACT_MALLOC_SIZE
-				    "  Allocated Size"
+                                    "  Allocated Size"
 #endif
-				    "  Use Page     Mark Time(ms)    Sweep Time(ms)  Prepare Time(ms)  LivingObj    FreeObj RemovedObj   EmptyObj"
+                                    "  Use Page     Mark Time(ms)    Sweep Time(ms)  Prepare Time(ms)  LivingObj    FreeObj RemovedObj   EmptyObj"
 #if RGENGC_PROFILE
-				    " OldgenObj RemNormObj RemShadObj"
+                                    " OldgenObj RemNormObj RemShadObj"
 #endif
 #if GC_PROFILE_DETAIL_MEMORY
-				    " MaxRSS(KB) MinorFLT MajorFLT"
+                                    " MaxRSS(KB) MinorFLT MajorFLT"
 #endif
                                     "\n";
         append(out, rb_str_new_cstr(str));
 
-	for (i = 0; i < count; i++) {
-	    record = &objspace->profile.records[i];
-	    append(out, rb_sprintf("%5"PRIuSIZE" %4s/%c/%6s%c %13"PRIuSIZE" %15"PRIuSIZE
+        for (i = 0; i < count; i++) {
+            record = &objspace->profile.records[i];
+            append(out, rb_sprintf("%5"PRIuSIZE" %4s/%c/%6s%c %13"PRIuSIZE" %15"PRIuSIZE
 #if CALC_EXACT_MALLOC_SIZE
-				   " %15"PRIuSIZE
+                                   " %15"PRIuSIZE
 #endif
-				   " %9"PRIuSIZE" %17.12f %17.12f %17.12f %10"PRIuSIZE" %10"PRIuSIZE" %10"PRIuSIZE" %10"PRIuSIZE
+                                   " %9"PRIuSIZE" %17.12f %17.12f %17.12f %10"PRIuSIZE" %10"PRIuSIZE" %10"PRIuSIZE" %10"PRIuSIZE
 #if RGENGC_PROFILE
-				   "%10"PRIuSIZE" %10"PRIuSIZE" %10"PRIuSIZE
+                                   "%10"PRIuSIZE" %10"PRIuSIZE" %10"PRIuSIZE
 #endif
 #if GC_PROFILE_DETAIL_MEMORY
-				   "%11ld %8ld %8ld"
-#endif
-
-				   "\n",
-				   i+1,
-				   gc_profile_dump_major_reason(record->flags, reason_str),
-				   (record->flags & GPR_FLAG_HAVE_FINALIZE) ? 'F' : '.',
-				   (record->flags & GPR_FLAG_NEWOBJ) ? "NEWOBJ" :
-				   (record->flags & GPR_FLAG_MALLOC) ? "MALLOC" :
-				   (record->flags & GPR_FLAG_METHOD) ? "METHOD" :
-				   (record->flags & GPR_FLAG_CAPI)   ? "CAPI__" : "??????",
-				   (record->flags & GPR_FLAG_STRESS) ? '!' : ' ',
-				   record->allocate_increase, record->allocate_limit,
+                                   "%11ld %8ld %8ld"
+#endif
+
+                                   "\n",
+                                   i+1,
+                                   gc_profile_dump_major_reason(record->flags, reason_str),
+                                   (record->flags & GPR_FLAG_HAVE_FINALIZE) ? 'F' : '.',
+                                   (record->flags & GPR_FLAG_NEWOBJ) ? "NEWOBJ" :
+                                   (record->flags & GPR_FLAG_MALLOC) ? "MALLOC" :
+                                   (record->flags & GPR_FLAG_METHOD) ? "METHOD" :
+                                   (record->flags & GPR_FLAG_CAPI)   ? "CAPI__" : "??????",
+                                   (record->flags & GPR_FLAG_STRESS) ? '!' : ' ',
+                                   record->allocate_increase, record->allocate_limit,
 #if CALC_EXACT_MALLOC_SIZE
-				   record->allocated_size,
+                                   record->allocated_size,
 #endif
-				   record->heap_use_pages,
-				   record->gc_mark_time*1000,
-				   record->gc_sweep_time*1000,
-				   record->prepare_time*1000,
+                                   record->heap_use_pages,
+                                   record->gc_mark_time*1000,
+                                   record->gc_sweep_time*1000,
+                                   record->prepare_time*1000,
 
-				   record->heap_live_objects,
-				   record->heap_free_objects,
-				   record->removing_objects,
-				   record->empty_objects
+                                   record->heap_live_objects,
+                                   record->heap_free_objects,
+                                   record->removing_objects,
+                                   record->empty_objects
 #if RGENGC_PROFILE
-				   ,
-				   record->old_objects,
-				   record->remembered_normal_objects,
-				   record->remembered_shady_objects
+                                   ,
+                                   record->old_objects,
+                                   record->remembered_normal_objects,
+                                   record->remembered_shady_objects
 #endif
 #if GC_PROFILE_DETAIL_MEMORY
-				   ,
-				   record->maxrss / 1024,
-				   record->minflt,
-				   record->majflt
+                                   ,
+                                   record->maxrss / 1024,
+                                   record->minflt,
+                                   record->majflt
 #endif
 
-		       ));
-	}
+                       ));
+        }
 #endif
     }
 }
@@ -13266,12 +13961,12 @@ gc_profile_total_time(VALUE self)
     rb_objspace_t *objspace = &rb_objspace;
 
     if (objspace->profile.run && objspace->profile.next_index > 0) {
-	size_t i;
-	size_t count = objspace->profile.next_index;
+        size_t i;
+        size_t count = objspace->profile.next_index;
 
-	for (i = 0; i < count; i++) {
-	    time += objspace->profile.records[i].gc_time;
-	}
+        for (i = 0; i < count; i++) {
+            time += objspace->profile.records[i].gc_time;
+        }
     }
     return DBL2NUM(time);
 }
@@ -13280,7 +13975,7 @@ gc_profile_total_time(VALUE self)
  *  call-seq:
  *    GC::Profiler.enabled?	-> true or false
  *
- *  The current status of GC profile mode.
+ *  The current status of \GC profile mode.
  */
 
 static VALUE
@@ -13294,7 +13989,7 @@ gc_profile_enable_get(VALUE self)
  *  call-seq:
  *    GC::Profiler.enable	-> nil
  *
- *  Starts the GC profiler.
+ *  Starts the \GC profiler.
  *
  */
 
@@ -13311,7 +14006,7 @@ gc_profile_enable(VALUE _)
  *  call-seq:
  *    GC::Profiler.disable	-> nil
  *
- *  Stops the GC profiler.
+ *  Stops the \GC profiler.
  *
  */
 
@@ -13334,36 +14029,36 @@ type_name(int type, VALUE obj)
 {
     switch (type) {
 #define TYPE_NAME(t) case (t): return #t;
-	    TYPE_NAME(T_NONE);
-	    TYPE_NAME(T_OBJECT);
-	    TYPE_NAME(T_CLASS);
-	    TYPE_NAME(T_MODULE);
-	    TYPE_NAME(T_FLOAT);
-	    TYPE_NAME(T_STRING);
-	    TYPE_NAME(T_REGEXP);
-	    TYPE_NAME(T_ARRAY);
-	    TYPE_NAME(T_HASH);
-	    TYPE_NAME(T_STRUCT);
-	    TYPE_NAME(T_BIGNUM);
-	    TYPE_NAME(T_FILE);
-	    TYPE_NAME(T_MATCH);
-	    TYPE_NAME(T_COMPLEX);
-	    TYPE_NAME(T_RATIONAL);
-	    TYPE_NAME(T_NIL);
-	    TYPE_NAME(T_TRUE);
-	    TYPE_NAME(T_FALSE);
-	    TYPE_NAME(T_SYMBOL);
-	    TYPE_NAME(T_FIXNUM);
-	    TYPE_NAME(T_UNDEF);
-	    TYPE_NAME(T_IMEMO);
-	    TYPE_NAME(T_ICLASS);
+            TYPE_NAME(T_NONE);
+            TYPE_NAME(T_OBJECT);
+            TYPE_NAME(T_CLASS);
+            TYPE_NAME(T_MODULE);
+            TYPE_NAME(T_FLOAT);
+            TYPE_NAME(T_STRING);
+            TYPE_NAME(T_REGEXP);
+            TYPE_NAME(T_ARRAY);
+            TYPE_NAME(T_HASH);
+            TYPE_NAME(T_STRUCT);
+            TYPE_NAME(T_BIGNUM);
+            TYPE_NAME(T_FILE);
+            TYPE_NAME(T_MATCH);
+            TYPE_NAME(T_COMPLEX);
+            TYPE_NAME(T_RATIONAL);
+            TYPE_NAME(T_NIL);
+            TYPE_NAME(T_TRUE);
+            TYPE_NAME(T_FALSE);
+            TYPE_NAME(T_SYMBOL);
+            TYPE_NAME(T_FIXNUM);
+            TYPE_NAME(T_UNDEF);
+            TYPE_NAME(T_IMEMO);
+            TYPE_NAME(T_ICLASS);
             TYPE_NAME(T_MOVED);
-	    TYPE_NAME(T_ZOMBIE);
+            TYPE_NAME(T_ZOMBIE);
       case T_DATA:
-	if (obj && rb_objspace_data_type_name(obj)) {
-	    return rb_objspace_data_type_name(obj);
-	}
-	return "T_DATA";
+        if (obj && rb_objspace_data_type_name(obj)) {
+            return rb_objspace_data_type_name(obj);
+        }
+        return "T_DATA";
 #undef TYPE_NAME
     }
     return "unknown";
@@ -13395,24 +14090,15 @@ rb_method_type_name(rb_method_type_t type)
     rb_bug("rb_method_type_name: unreachable (type: %d)", type);
 }
 
-/* from array.c */
-# define ARY_SHARED_P(ary) \
-    (GC_ASSERT(!FL_TEST((ary), ELTS_SHARED) || !FL_TEST((ary), RARRAY_EMBED_FLAG)), \
-     FL_TEST((ary),ELTS_SHARED)!=0)
-# define ARY_EMBED_P(ary) \
-    (GC_ASSERT(!FL_TEST((ary), ELTS_SHARED) || !FL_TEST((ary), RARRAY_EMBED_FLAG)), \
-     FL_TEST((ary), RARRAY_EMBED_FLAG)!=0)
-
 static void
-rb_raw_iseq_info(char *buff, const int buff_size, const rb_iseq_t *iseq)
+rb_raw_iseq_info(char *const buff, const size_t buff_size, const rb_iseq_t *iseq)
 {
     if (buff_size > 0 && ISEQ_BODY(iseq) && ISEQ_BODY(iseq)->location.label && !RB_TYPE_P(ISEQ_BODY(iseq)->location.pathobj, T_MOVED)) {
-	VALUE path = rb_iseq_path(iseq);
-        VALUE n = ISEQ_BODY(iseq)->location.first_lineno;
+        VALUE path = rb_iseq_path(iseq);
+        int n = ISEQ_BODY(iseq)->location.first_lineno;
         snprintf(buff, buff_size, " %s@%s:%d",
                  RSTRING_PTR(ISEQ_BODY(iseq)->location.label),
-		 RSTRING_PTR(path),
-		 n ? FIX2INT(n) : 0 );
+                 RSTRING_PTR(path), n);
     }
 }
 
@@ -13425,33 +14111,39 @@ str_len_no_raise(VALUE str)
     return (int)len;
 }
 
-const char *
-rb_raw_obj_info(char *buff, const int buff_size, VALUE obj)
+#define BUFF_ARGS buff + pos, buff_size - pos
+#define APPEND_F(...) if ((pos += snprintf(BUFF_ARGS, "" __VA_ARGS__)) >= buff_size) goto end
+#define APPEND_S(s) do { \
+        if ((pos + (int)rb_strlen_lit(s)) >= buff_size) { \
+            goto end; \
+        } \
+        else { \
+            memcpy(buff + pos, (s), rb_strlen_lit(s) + 1); \
+        } \
+    } while (0)
+#define TF(c) ((c) != 0 ? "true" : "false")
+#define C(c, s) ((c) != 0 ? (s) : " ")
+
+static size_t
+rb_raw_obj_info_common(char *const buff, const size_t buff_size, const VALUE obj)
 {
-    int pos = 0;
-    void *poisoned = asan_poisoned_object_p(obj);
-    asan_unpoison_object(obj, false);
+    size_t pos = 0;
 
-#define BUFF_ARGS buff + pos, buff_size - pos
-#define APPENDF(f) if ((pos += snprintf f) >= buff_size) goto end
     if (SPECIAL_CONST_P(obj)) {
-        APPENDF((BUFF_ARGS, "%s", obj_type_name(obj)));
+        APPEND_F("%s", obj_type_name(obj));
 
         if (FIXNUM_P(obj)) {
-            APPENDF((BUFF_ARGS, " %ld", FIX2LONG(obj)));
+            APPEND_F(" %ld", FIX2LONG(obj));
         }
         else if (SYMBOL_P(obj)) {
-            APPENDF((BUFF_ARGS, " %s", rb_id2name(SYM2ID(obj))));
+            APPEND_F(" %s", rb_id2name(SYM2ID(obj)));
         }
     }
     else {
-#define TF(c) ((c) != 0 ? "true" : "false")
-#define C(c, s) ((c) != 0 ? (s) : " ")
-	const int type = BUILTIN_TYPE(obj);
-	const int age = RVALUE_FLAGS_AGE(RBASIC(obj)->flags);
+        const int age = RVALUE_FLAGS_AGE(RBASIC(obj)->flags);
 
         if (is_pointer_to_heap(&rb_objspace, (void *)obj)) {
-            APPENDF((BUFF_ARGS, "%p [%d%s%s%s%s%s%s] %s ",
+            APPEND_F("%p [%d%s%s%s%s%s%s] %s ",
                      (void *)obj, age,
                      C(RVALUE_UNCOLLECTIBLE_BITMAP(obj),  "L"),
                      C(RVALUE_MARK_BITMAP(obj),           "M"),
@@ -13459,102 +14151,111 @@ rb_raw_obj_info(char *buff, const int buff_size, VALUE obj)
                      C(RVALUE_MARKING_BITMAP(obj),        "R"),
                      C(RVALUE_WB_UNPROTECTED_BITMAP(obj), "U"),
                      C(rb_objspace_garbage_object_p(obj), "G"),
-                     obj_type_name(obj)));
+                     obj_type_name(obj));
         }
         else {
             /* fake */
-            APPENDF((BUFF_ARGS, "%p [%dXXXX] %s",
+            APPEND_F("%p [%dXXXX] %s",
                      (void *)obj, age,
-                     obj_type_name(obj)));
+                     obj_type_name(obj));
         }
 
-	if (internal_object_p(obj)) {
-	    /* ignore */
-	}
-	else if (RBASIC(obj)->klass == 0) {
-            APPENDF((BUFF_ARGS, "(temporary internal)"));
-	}
-	else {
-            if (RTEST(RBASIC(obj)->klass)) {
+        if (internal_object_p(obj)) {
+            /* ignore */
+        }
+        else if (RBASIC(obj)->klass == 0) {
+            APPEND_S("(temporary internal)");
+        }
+        else if (RTEST(RBASIC(obj)->klass)) {
             VALUE class_path = rb_class_path_cached(RBASIC(obj)->klass);
-	    if (!NIL_P(class_path)) {
-                APPENDF((BUFF_ARGS, "(%s)", RSTRING_PTR(class_path)));
-	    }
+            if (!NIL_P(class_path)) {
+                APPEND_F("(%s)", RSTRING_PTR(class_path));
             }
-	}
+        }
 
 #if GC_DEBUG
-        APPENDF((BUFF_ARGS, "@%s:%d", RANY(obj)->file, RANY(obj)->line));
+        APPEND_F("@%s:%d", RANY(obj)->file, RANY(obj)->line);
 #endif
+    }
+  end:
+
+    return pos;
+}
+
+static size_t
+rb_raw_obj_info_buitin_type(char *const buff, const size_t buff_size, const VALUE obj, size_t pos)
+{
+    if (LIKELY(pos < buff_size) && !SPECIAL_CONST_P(obj)) {
+        const enum ruby_value_type type = BUILTIN_TYPE(obj);
 
-	switch (type) {
-	  case T_NODE:
-	    UNEXPECTED_NODE(rb_raw_obj_info);
-	    break;
-	  case T_ARRAY:
-            if (FL_TEST(obj, ELTS_SHARED)) {
-                APPENDF((BUFF_ARGS, "shared -> %s",
-                         rb_obj_info(RARRAY(obj)->as.heap.aux.shared_root)));
+        switch (type) {
+          case T_NODE:
+            UNEXPECTED_NODE(rb_raw_obj_info);
+            break;
+          case T_ARRAY:
+            if (ARY_SHARED_P(obj)) {
+                APPEND_S("shared -> ");
+                rb_raw_obj_info(BUFF_ARGS, ARY_SHARED_ROOT(obj));
             }
-            else if (FL_TEST(obj, RARRAY_EMBED_FLAG)) {
-                APPENDF((BUFF_ARGS, "[%s%s] len: %ld (embed)",
+            else if (ARY_EMBED_P(obj)) {
+                APPEND_F("[%s%s] len: %ld (embed)",
                          C(ARY_EMBED_P(obj),  "E"),
                          C(ARY_SHARED_P(obj), "S"),
-                         RARRAY_LEN(obj)));
+                         RARRAY_LEN(obj));
             }
             else {
-                APPENDF((BUFF_ARGS, "[%s%s%s] len: %ld, capa:%ld ptr:%p",
+                APPEND_F("[%s%s%s] len: %ld, capa:%ld ptr:%p",
                          C(ARY_EMBED_P(obj),  "E"),
                          C(ARY_SHARED_P(obj), "S"),
                          C(RARRAY_TRANSIENT_P(obj), "T"),
                          RARRAY_LEN(obj),
                          ARY_EMBED_P(obj) ? -1L : RARRAY(obj)->as.heap.aux.capa,
-                         (void *)RARRAY_CONST_PTR_TRANSIENT(obj)));
+                         (void *)RARRAY_CONST_PTR_TRANSIENT(obj));
             }
-	    break;
-	  case T_STRING: {
+            break;
+          case T_STRING: {
             if (STR_SHARED_P(obj)) {
-                APPENDF((BUFF_ARGS, " [shared] len: %ld", RSTRING_LEN(obj)));
+                APPEND_F(" [shared] len: %ld", RSTRING_LEN(obj));
             }
             else {
-                if (STR_EMBED_P(obj)) APPENDF((BUFF_ARGS, " [embed]"));
+                if (STR_EMBED_P(obj)) APPEND_S(" [embed]");
 
-                APPENDF((BUFF_ARGS, " len: %ld, capa: %" PRIdSIZE, RSTRING_LEN(obj), rb_str_capacity(obj)));
+                APPEND_F(" len: %ld, capa: %" PRIdSIZE, RSTRING_LEN(obj), rb_str_capacity(obj));
             }
-            APPENDF((BUFF_ARGS, " \"%.*s\"", str_len_no_raise(obj), RSTRING_PTR(obj)));
-	    break;
-	  }
+            APPEND_F(" \"%.*s\"", str_len_no_raise(obj), RSTRING_PTR(obj));
+            break;
+          }
           case T_SYMBOL: {
-              VALUE fstr = RSYMBOL(obj)->fstr;
-              ID id = RSYMBOL(obj)->id;
-              if (RB_TYPE_P(fstr, T_STRING)) {
-                  APPENDF((BUFF_ARGS, ":%s id:%d", RSTRING_PTR(fstr), (unsigned int)id));
-              }
-              else {
-                  APPENDF((BUFF_ARGS, "(%p) id:%d", (void *)fstr, (unsigned int)id));
-              }
-              break;
+            VALUE fstr = RSYMBOL(obj)->fstr;
+            ID id = RSYMBOL(obj)->id;
+            if (RB_TYPE_P(fstr, T_STRING)) {
+                APPEND_F(":%s id:%d", RSTRING_PTR(fstr), (unsigned int)id);
+            }
+            else {
+                APPEND_F("(%p) id:%d", (void *)fstr, (unsigned int)id);
+            }
+            break;
           }
           case T_MOVED: {
-            APPENDF((BUFF_ARGS, "-> %p", (void*)rb_gc_location(obj)));
+            APPEND_F("-> %p", (void*)rb_gc_location(obj));
             break;
           }
           case T_HASH: {
-              APPENDF((BUFF_ARGS, "[%c%c] %"PRIdSIZE,
-                       RHASH_AR_TABLE_P(obj) ? 'A' : 'S',
-                       RHASH_TRANSIENT_P(obj) ? 'T' : ' ',
-                       RHASH_SIZE(obj)));
-              break;
+            APPEND_F("[%c%c] %"PRIdSIZE,
+                     RHASH_AR_TABLE_P(obj) ? 'A' : 'S',
+                     RHASH_TRANSIENT_P(obj) ? 'T' : ' ',
+                     RHASH_SIZE(obj));
+            break;
           }
           case T_CLASS:
           case T_MODULE:
             {
                 VALUE class_path = rb_class_path_cached(obj);
                 if (!NIL_P(class_path)) {
-                    APPENDF((BUFF_ARGS, "%s", RSTRING_PTR(class_path)));
+                    APPEND_F("%s", RSTRING_PTR(class_path));
                 }
                 else {
-                    APPENDF((BUFF_ARGS, "(annon)"));
+                    APPEND_S("(annon)");
                 }
                 break;
             }
@@ -13562,55 +14263,55 @@ rb_raw_obj_info(char *buff, const int buff_size, VALUE obj)
             {
                 VALUE class_path = rb_class_path_cached(RBASIC_CLASS(obj));
                 if (!NIL_P(class_path)) {
-                    APPENDF((BUFF_ARGS, "src:%s", RSTRING_PTR(class_path)));
+                    APPEND_F("src:%s", RSTRING_PTR(class_path));
                 }
                 break;
             }
           case T_OBJECT:
             {
-                uint32_t len = ROBJECT_NUMIV(obj);
+                uint32_t len = ROBJECT_IV_CAPACITY(obj);
 
                 if (RANY(obj)->as.basic.flags & ROBJECT_EMBED) {
-                    APPENDF((BUFF_ARGS, "(embed) len:%d", len));
+                    APPEND_F("(embed) len:%d", len);
                 }
                 else {
                     VALUE *ptr = ROBJECT_IVPTR(obj);
-                    APPENDF((BUFF_ARGS, "len:%d ptr:%p", len, (void *)ptr));
+                    APPEND_F("len:%d ptr:%p", len, (void *)ptr);
                 }
             }
             break;
-	  case T_DATA: {
-	    const struct rb_block *block;
-	    const rb_iseq_t *iseq;
-	    if (rb_obj_is_proc(obj) &&
-		(block = vm_proc_block(obj)) != NULL &&
-		(vm_block_type(block) == block_type_iseq) &&
-		(iseq = vm_block_iseq(block)) != NULL) {
+          case T_DATA: {
+            const struct rb_block *block;
+            const rb_iseq_t *iseq;
+            if (rb_obj_is_proc(obj) &&
+                (block = vm_proc_block(obj)) != NULL &&
+                (vm_block_type(block) == block_type_iseq) &&
+                (iseq = vm_block_iseq(block)) != NULL) {
                 rb_raw_iseq_info(BUFF_ARGS, iseq);
-	    }
+            }
             else if (rb_ractor_p(obj)) {
                 rb_ractor_t *r = (void *)DATA_PTR(obj);
                 if (r) {
-                    APPENDF((BUFF_ARGS, "r:%d", r->pub.id));
+                    APPEND_F("r:%d", r->pub.id);
+                }
+            }
+            else {
+                const char * const type_name = rb_objspace_data_type_name(obj);
+                if (type_name) {
+                    APPEND_F("%s", type_name);
                 }
             }
-	    else {
-		const char * const type_name = rb_objspace_data_type_name(obj);
-		if (type_name) {
-                    APPENDF((BUFF_ARGS, "%s", type_name));
-		}
-	    }
-	    break;
-	  }
-	  case T_IMEMO: {
-            APPENDF((BUFF_ARGS, "<%s> ", rb_imemo_name(imemo_type(obj))));
-
-	    switch (imemo_type(obj)) {
-	      case imemo_ment:
+            break;
+          }
+          case T_IMEMO: {
+            APPEND_F("<%s> ", rb_imemo_name(imemo_type(obj)));
+
+            switch (imemo_type(obj)) {
+              case imemo_ment:
                 {
                     const rb_method_entry_t *me = &RANY(obj)->as.imemo.ment;
 
-                    APPENDF((BUFF_ARGS, ":%s (%s%s%s%s) type:%s alias:%d owner:%p defined_class:%p",
+                    APPEND_F(":%s (%s%s%s%s) type:%s aliased:%d owner:%p defined_class:%p",
                              rb_id2name(me->called_id),
                              METHOD_ENTRY_VISI(me) == METHOD_VISI_PUBLIC ?  "pub" :
                              METHOD_ENTRY_VISI(me) == METHOD_VISI_PRIVATE ? "pri" : "pro",
@@ -13618,14 +14319,16 @@ rb_raw_obj_info(char *buff, const int buff_size, VALUE obj)
                              METHOD_ENTRY_CACHED(me) ? ",cc" : "",
                              METHOD_ENTRY_INVALIDATED(me) ? ",inv" : "",
                              me->def ? rb_method_type_name(me->def->type) : "NULL",
-                             me->def ? me->def->alias_count : -1,
+                             me->def ? me->def->aliased : -1,
                              (void *)me->owner, // obj_info(me->owner),
-                             (void *)me->defined_class)); //obj_info(me->defined_class)));
+                             (void *)me->defined_class); //obj_info(me->defined_class)));
 
                     if (me->def) {
                         switch (me->def->type) {
                           case VM_METHOD_TYPE_ISEQ:
-                            APPENDF((BUFF_ARGS, " (iseq:%s)", obj_info((VALUE)me->def->body.iseq.iseqptr)));
+                            APPEND_S(" (iseq:");
+                            rb_raw_obj_info(BUFF_ARGS, (VALUE)me->def->body.iseq.iseqptr);
+                            APPEND_S(")");
                             break;
                           default:
                             break;
@@ -13634,19 +14337,19 @@ rb_raw_obj_info(char *buff, const int buff_size, VALUE obj)
 
                     break;
                 }
-	      case imemo_iseq: {
-		const rb_iseq_t *iseq = (const rb_iseq_t *)obj;
+              case imemo_iseq: {
+                const rb_iseq_t *iseq = (const rb_iseq_t *)obj;
                 rb_raw_iseq_info(BUFF_ARGS, iseq);
-		break;
-	      }
+                break;
+              }
               case imemo_callinfo:
                 {
                     const struct rb_callinfo *ci = (const struct rb_callinfo *)obj;
-                    APPENDF((BUFF_ARGS, "(mid:%s, flag:%x argc:%d, kwarg:%s)",
+                    APPEND_F("(mid:%s, flag:%x argc:%d, kwarg:%s)",
                              rb_id2name(vm_ci_mid(ci)),
                              vm_ci_flag(ci),
                              vm_ci_argc(ci),
-                             vm_ci_kwarg(ci) ? "available" : "NULL"));
+                             vm_ci_kwarg(ci) ? "available" : "NULL");
                     break;
                 }
               case imemo_callcache:
@@ -13655,50 +14358,71 @@ rb_raw_obj_info(char *buff, const int buff_size, VALUE obj)
                     VALUE class_path = cc->klass ? rb_class_path_cached(cc->klass) : Qnil;
                     const rb_callable_method_entry_t *cme = vm_cc_cme(cc);
 
-                    APPENDF((BUFF_ARGS, "(klass:%s cme:%s%s (%p) call:%p",
+                    APPEND_F("(klass:%s cme:%s%s (%p) call:%p",
                              NIL_P(class_path) ? (cc->klass ? "??" : "<NULL>") : RSTRING_PTR(class_path),
                              cme ? rb_id2name(cme->called_id) : "<NULL>",
                              cme ? (METHOD_ENTRY_INVALIDATED(cme) ? " [inv]" : "") : "",
                              (void *)cme,
-                             (void *)vm_cc_call(cc)));
+                             (void *)vm_cc_call(cc));
                     break;
                 }
-	      default:
-		break;
-	    }
-	  }
-	  default:
-	    break;
-	}
-#undef TF
-#undef C
+              default:
+                break;
+            }
+          }
+          default:
+            break;
+        }
     }
   end:
-    if (poisoned) {
-        asan_poison_object(obj);
+
+    return pos;
+}
+
+#undef TF
+#undef C
+
+const char *
+rb_raw_obj_info(char *const buff, const size_t buff_size, VALUE obj)
+{
+    asan_unpoisoning_object(obj) {
+        size_t pos = rb_raw_obj_info_common(buff, buff_size, obj);
+        pos = rb_raw_obj_info_buitin_type(buff, buff_size, obj, pos);
+        if (pos >= buff_size) {} // truncated
     }
 
     return buff;
-#undef APPENDF
-#undef BUFF_ARGS
 }
 
+#undef APPEND_S
+#undef APPEND_F
+#undef BUFF_ARGS
+
 #if RGENGC_OBJ_INFO
 #define OBJ_INFO_BUFFERS_NUM  10
 #define OBJ_INFO_BUFFERS_SIZE 0x100
-static int obj_info_buffers_index = 0;
+static rb_atomic_t obj_info_buffers_index = 0;
 static char obj_info_buffers[OBJ_INFO_BUFFERS_NUM][OBJ_INFO_BUFFERS_SIZE];
 
-static const char *
-obj_info(VALUE obj)
+/* Increments *var atomically and resets *var to 0 when maxval is
+ * reached. Returns the wraparound old *var value (0...maxval). */
+static rb_atomic_t
+atomic_inc_wraparound(rb_atomic_t *var, const rb_atomic_t maxval)
 {
-    const int index = obj_info_buffers_index++;
-    char *const buff = &obj_info_buffers[index][0];
-
-    if (obj_info_buffers_index >= OBJ_INFO_BUFFERS_NUM) {
-	obj_info_buffers_index = 0;
+    rb_atomic_t oldval = RUBY_ATOMIC_FETCH_ADD(*var, 1);
+    if (UNLIKELY(oldval >= maxval - 1)) { // wraparound *var
+        const rb_atomic_t newval = oldval + 1;
+        RUBY_ATOMIC_CAS(*var, newval, newval % maxval);
+        oldval %= maxval;
     }
+    return oldval;
+}
 
+static const char *
+obj_info(VALUE obj)
+{
+    rb_atomic_t index = atomic_inc_wraparound(&obj_info_buffers_index, OBJ_INFO_BUFFERS_NUM);
+    char *const buff = obj_info_buffers[index];
     return rb_raw_obj_info(buff, OBJ_INFO_BUFFERS_SIZE, obj);
 }
 #else
@@ -13797,7 +14521,7 @@ rb_gcdebug_add_stress_to_class(int argc, VALUE *argv, VALUE self)
     rb_objspace_t *objspace = &rb_objspace;
 
     if (!stress_to_class) {
-	stress_to_class = rb_ary_tmp_new(argc);
+        stress_to_class = rb_ary_hidden_new(argc);
     }
     rb_ary_cat(stress_to_class, argv, argc);
     return self;
@@ -13818,12 +14542,12 @@ rb_gcdebug_remove_stress_to_class(int argc, VALUE *argv, VALUE self)
     int i;
 
     if (stress_to_class) {
-	for (i = 0; i < argc; ++i) {
-	    rb_ary_delete_same(stress_to_class, argv[i]);
-	}
-	if (RARRAY_LEN(stress_to_class) == 0) {
-	    stress_to_class = 0;
-	}
+        for (i = 0; i < argc; ++i) {
+            rb_ary_delete_same(stress_to_class, argv[i]);
+        }
+        if (RARRAY_LEN(stress_to_class) == 0) {
+            stress_to_class = 0;
+        }
     }
     return Qnil;
 }
@@ -13886,6 +14610,22 @@ rb_gcdebug_remove_stress_to_class(int argc, VALUE *argv, VALUE self)
  */
 
 #include "gc.rbinc"
+/*
+ *  call-seq:
+ *      GC.using_rvargc? -> true or false
+ *
+ *  Returns true if using experimental feature Variable Width Allocation, false
+ *  otherwise.
+ */
+static VALUE
+gc_using_rvargc_p(VALUE mod)
+{
+#if USE_RVARGC
+    return Qtrue;
+#else
+    return Qfalse;
+#endif
+}
 
 void
 Init_GC(void)
@@ -13899,7 +14639,8 @@ Init_GC(void)
 
     gc_constants = rb_hash_new();
     rb_hash_aset(gc_constants, ID2SYM(rb_intern("DEBUG")), RBOOL(GC_DEBUG));
-    rb_hash_aset(gc_constants, ID2SYM(rb_intern("BASE_SLOT_SIZE")), SIZET2NUM(BASE_SLOT_SIZE));
+    rb_hash_aset(gc_constants, ID2SYM(rb_intern("BASE_SLOT_SIZE")), SIZET2NUM(BASE_SLOT_SIZE - RVALUE_OVERHEAD));
+    rb_hash_aset(gc_constants, ID2SYM(rb_intern("RVALUE_OVERHEAD")), SIZET2NUM(RVALUE_OVERHEAD));
     rb_hash_aset(gc_constants, ID2SYM(rb_intern("RVALUE_SIZE")), SIZET2NUM(sizeof(RVALUE)));
     rb_hash_aset(gc_constants, ID2SYM(rb_intern("HEAP_PAGE_OBJ_LIMIT")), SIZET2NUM(HEAP_PAGE_OBJ_LIMIT));
     rb_hash_aset(gc_constants, ID2SYM(rb_intern("HEAP_PAGE_BITMAP_SIZE")), SIZET2NUM(HEAP_PAGE_BITMAP_SIZE));
@@ -13937,23 +14678,23 @@ Init_GC(void)
     rb_define_module_function(rb_mObjSpace, "count_objects", count_objects, -1);
 
     {
-	VALUE rb_cWeakMap = rb_define_class_under(rb_mObjSpace, "WeakMap", rb_cObject);
-	rb_define_alloc_func(rb_cWeakMap, wmap_allocate);
-	rb_define_method(rb_cWeakMap, "[]=", wmap_aset, 2);
-	rb_define_method(rb_cWeakMap, "[]", wmap_aref, 1);
-	rb_define_method(rb_cWeakMap, "include?", wmap_has_key, 1);
-	rb_define_method(rb_cWeakMap, "member?", wmap_has_key, 1);
-	rb_define_method(rb_cWeakMap, "key?", wmap_has_key, 1);
-	rb_define_method(rb_cWeakMap, "inspect", wmap_inspect, 0);
-	rb_define_method(rb_cWeakMap, "each", wmap_each, 0);
-	rb_define_method(rb_cWeakMap, "each_pair", wmap_each, 0);
-	rb_define_method(rb_cWeakMap, "each_key", wmap_each_key, 0);
-	rb_define_method(rb_cWeakMap, "each_value", wmap_each_value, 0);
-	rb_define_method(rb_cWeakMap, "keys", wmap_keys, 0);
-	rb_define_method(rb_cWeakMap, "values", wmap_values, 0);
-	rb_define_method(rb_cWeakMap, "size", wmap_size, 0);
-	rb_define_method(rb_cWeakMap, "length", wmap_size, 0);
-	rb_include_module(rb_cWeakMap, rb_mEnumerable);
+        VALUE rb_cWeakMap = rb_define_class_under(rb_mObjSpace, "WeakMap", rb_cObject);
+        rb_define_alloc_func(rb_cWeakMap, wmap_allocate);
+        rb_define_method(rb_cWeakMap, "[]=", wmap_aset, 2);
+        rb_define_method(rb_cWeakMap, "[]", wmap_aref, 1);
+        rb_define_method(rb_cWeakMap, "include?", wmap_has_key, 1);
+        rb_define_method(rb_cWeakMap, "member?", wmap_has_key, 1);
+        rb_define_method(rb_cWeakMap, "key?", wmap_has_key, 1);
+        rb_define_method(rb_cWeakMap, "inspect", wmap_inspect, 0);
+        rb_define_method(rb_cWeakMap, "each", wmap_each, 0);
+        rb_define_method(rb_cWeakMap, "each_pair", wmap_each, 0);
+        rb_define_method(rb_cWeakMap, "each_key", wmap_each_key, 0);
+        rb_define_method(rb_cWeakMap, "each_value", wmap_each_value, 0);
+        rb_define_method(rb_cWeakMap, "keys", wmap_keys, 0);
+        rb_define_method(rb_cWeakMap, "values", wmap_values, 0);
+        rb_define_method(rb_cWeakMap, "size", wmap_size, 0);
+        rb_define_method(rb_cWeakMap, "length", wmap_size, 0);
+        rb_include_module(rb_cWeakMap, rb_mEnumerable);
     }
 
     /* internal methods */
@@ -13964,30 +14705,48 @@ Init_GC(void)
     rb_define_singleton_method(rb_mGC, "malloc_allocations", gc_malloc_allocations, 0);
 #endif
 
+    rb_define_singleton_method(rb_mGC, "using_rvargc?", gc_using_rvargc_p, 0);
+
+    if (GC_COMPACTION_SUPPORTED) {
+        rb_define_singleton_method(rb_mGC, "compact", gc_compact, 0);
+        rb_define_singleton_method(rb_mGC, "auto_compact", gc_get_auto_compact, 0);
+        rb_define_singleton_method(rb_mGC, "auto_compact=", gc_set_auto_compact, 1);
+        rb_define_singleton_method(rb_mGC, "latest_compact_info", gc_compact_stats, 0);
+    }
+    else {
+        rb_define_singleton_method(rb_mGC, "compact", rb_f_notimplement, 0);
+        rb_define_singleton_method(rb_mGC, "auto_compact", rb_f_notimplement, 0);
+        rb_define_singleton_method(rb_mGC, "auto_compact=", rb_f_notimplement, 1);
+        rb_define_singleton_method(rb_mGC, "latest_compact_info", rb_f_notimplement, 0);
+        /* When !GC_COMPACTION_SUPPORTED, this method is not defined in gc.rb */
+        rb_define_singleton_method(rb_mGC, "verify_compaction_references", rb_f_notimplement, -1);
+    }
+
 #if GC_DEBUG_STRESS_TO_CLASS
     rb_define_singleton_method(rb_mGC, "add_stress_to_class", rb_gcdebug_add_stress_to_class, -1);
     rb_define_singleton_method(rb_mGC, "remove_stress_to_class", rb_gcdebug_remove_stress_to_class, -1);
 #endif
 
     {
-	VALUE opts;
-	/* GC build options */
-	rb_define_const(rb_mGC, "OPTS", opts = rb_ary_new());
+        VALUE opts;
+        /* \GC build options */
+        rb_define_const(rb_mGC, "OPTS", opts = rb_ary_new());
 #define OPT(o) if (o) rb_ary_push(opts, rb_fstring_lit(#o))
-	OPT(GC_DEBUG);
-	OPT(USE_RGENGC);
-	OPT(RGENGC_DEBUG);
-	OPT(RGENGC_CHECK_MODE);
-	OPT(RGENGC_PROFILE);
-	OPT(RGENGC_ESTIMATE_OLDMALLOC);
-	OPT(GC_PROFILE_MORE_DETAIL);
-	OPT(GC_ENABLE_LAZY_SWEEP);
-	OPT(CALC_EXACT_MALLOC_SIZE);
-	OPT(MALLOC_ALLOCATED_SIZE);
-	OPT(MALLOC_ALLOCATED_SIZE_CHECK);
-	OPT(GC_PROFILE_DETAIL_MEMORY);
+        OPT(GC_DEBUG);
+        OPT(USE_RGENGC);
+        OPT(RGENGC_DEBUG);
+        OPT(RGENGC_CHECK_MODE);
+        OPT(RGENGC_PROFILE);
+        OPT(RGENGC_ESTIMATE_OLDMALLOC);
+        OPT(GC_PROFILE_MORE_DETAIL);
+        OPT(GC_ENABLE_LAZY_SWEEP);
+        OPT(CALC_EXACT_MALLOC_SIZE);
+        OPT(MALLOC_ALLOCATED_SIZE);
+        OPT(MALLOC_ALLOCATED_SIZE_CHECK);
+        OPT(GC_PROFILE_DETAIL_MEMORY);
+        OPT(GC_COMPACTION_SUPPORTED);
 #undef OPT
-	OBJ_FREEZE(opts);
+        OBJ_FREEZE(opts);
     }
 }
 
diff --git a/gc.h b/gc.h
index 84c8eade63..23218c1a9e 100644
--- a/gc.h
+++ b/gc.h
@@ -6,10 +6,12 @@
 #define SET_MACHINE_STACK_END(p) __asm__ __volatile__ ("movq\t%%rsp, %0" : "=r" (*(p)))
 #elif defined(__i386) && defined(__GNUC__)
 #define SET_MACHINE_STACK_END(p) __asm__ __volatile__ ("movl\t%%esp, %0" : "=r" (*(p)))
-#elif (defined(__powerpc__) || defined(__powerpc64__)) && defined(__GNUC__) && !defined(_AIX)
+#elif (defined(__powerpc__) || defined(__powerpc64__)) && defined(__GNUC__) && !defined(_AIX) && !defined(__APPLE__) // Not Apple is NEEDED to unbreak ppc64 build on Darwin. Don't ask.
 #define SET_MACHINE_STACK_END(p) __asm__ __volatile__ ("mr\t%0, %%r1" : "=r" (*(p)))
 #elif (defined(__powerpc__) || defined(__powerpc64__)) && defined(__GNUC__) && defined(_AIX)
 #define SET_MACHINE_STACK_END(p) __asm__ __volatile__ ("mr %0,1" : "=r" (*(p)))
+#elif defined(__POWERPC__) && defined(__APPLE__) // Darwin ppc and ppc64
+#define SET_MACHINE_STACK_END(p) __asm__ volatile("mr %0, r1" : "=r" (*(p)))
 #elif defined(__aarch64__) && defined(__GNUC__)
 #define SET_MACHINE_STACK_END(p) __asm__ __volatile__ ("mov\t%0, sp" : "=r" (*(p)))
 #else
@@ -20,9 +22,9 @@ NOINLINE(void rb_gc_set_stack_end(VALUE **stack_end_p));
 
 #define RB_GC_SAVE_MACHINE_CONTEXT(th)				\
     do {							\
-	FLUSH_REGISTER_WINDOWS;					\
-	setjmp((th)->ec->machine.regs);				\
-	SET_MACHINE_STACK_END(&(th)->ec->machine.stack_end);	\
+        FLUSH_REGISTER_WINDOWS;					\
+        setjmp((th)->ec->machine.regs);				\
+        SET_MACHINE_STACK_END(&(th)->ec->machine.stack_end);	\
     } while (0)
 
 /* for GC debug */
@@ -44,13 +46,13 @@ static inline void
 rb_gc_debug_body(const char *mode, const char *msg, int st, void *ptr)
 {
     if (st == 0) {
-	ruby_gc_debug_indent--;
+        ruby_gc_debug_indent--;
     }
     rb_gc_debug_indent();
     ruby_debug_printf("%s: %s %s (%p)\n", mode, st ? "->" : "<-", msg, ptr);
 
     if (st) {
-	ruby_gc_debug_indent++;
+        ruby_gc_debug_indent++;
     }
 
     fflush(stdout);
@@ -88,9 +90,9 @@ rb_gc_debug_body(const char *mode, const char *msg, int st, void *ptr)
 RUBY_EXTERN int ruby_stack_grow_direction;
 int ruby_get_stack_grow_direction(volatile VALUE *addr);
 # define stack_growup_p(x) (			\
-	(ruby_stack_grow_direction ?		\
-	 ruby_stack_grow_direction :		\
-	 ruby_get_stack_grow_direction(x)) > 0)
+        (ruby_stack_grow_direction ?		\
+         ruby_stack_grow_direction :		\
+         ruby_get_stack_grow_direction(x)) > 0)
 # define STACK_UPPER(x, a, b) (stack_growup_p(x) ? (a) : (b))
 #endif
 
@@ -112,12 +114,12 @@ int ruby_get_stack_grow_direction(volatile VALUE *addr);
 #define IS_STACK_DIR_UPPER() STACK_DIR_UPPER(1,0)
 
 const char *rb_obj_info(VALUE obj);
-const char *rb_raw_obj_info(char *buff, const int buff_size, VALUE obj);
-
-VALUE rb_gc_disable_no_rest(void);
+const char *rb_raw_obj_info(char *const buff, const size_t buff_size, VALUE obj);
 
 struct rb_thread_struct;
 
+size_t rb_size_pool_slot_size(unsigned char pool_id);
+
 RUBY_SYMBOL_EXPORT_BEGIN
 
 /* exports for objspace module */
@@ -138,6 +140,8 @@ void rb_objspace_each_objects_without_setup(
 
 size_t rb_gc_obj_slot_size(VALUE obj);
 
+VALUE rb_gc_disable_no_rest(void);
+
 RUBY_SYMBOL_EXPORT_END
 
 #endif /* RUBY_GC_H */
diff --git a/gc.rb b/gc.rb
index e9fb8f883b..57aeeb9131 100644
--- a/gc.rb
+++ b/gc.rb
@@ -6,7 +6,7 @@
 #  Some of the underlying methods are also available via the ObjectSpace
 #  module.
 #
-#  You may obtain information about the operation of the GC through
+#  You may obtain information about the operation of the \GC through
 #  GC::Profiler.
 module GC
 
@@ -24,7 +24,7 @@ module GC
   #
   #     def GC.start(full_mark: true, immediate_sweep: true); end
   #
-  #  Use full_mark: false to perform a minor GC.
+  #  Use full_mark: false to perform a minor \GC.
   #  Use immediate_sweep: false to defer sweeping (use lazy sweep).
   #
   #  Note: These keyword arguments are implementation and version dependent. They
@@ -39,27 +39,6 @@ module GC
   end
 
   #  call-seq:
-  #     GC.auto_compact    -> true or false
-  #
-  #  Returns whether or not automatic compaction has been enabled.
-  #
-  def self.auto_compact
-    Primitive.gc_get_auto_compact
-  end
-
-  #  call-seq:
-  #     GC.auto_compact = flag
-  #
-  #  Updates automatic compaction mode.
-  #
-  #  When enabled, the compactor will execute on every major collection.
-  #
-  #  Enabling compaction will degrade performance on major collections.
-  def self.auto_compact=(flag)
-    Primitive.gc_set_auto_compact(flag)
-  end
-
-  #  call-seq:
   #     GC.enable    -> true or false
   #
   #  Enables garbage collection, returning +true+ if garbage
@@ -88,7 +67,7 @@ module GC
   #  call-seq:
   #    GC.stress	    -> integer, true or false
   #
-  #  Returns current status of GC stress mode.
+  #  Returns current status of \GC stress mode.
   def self.stress
     Primitive.gc_stress_get
   end
@@ -96,9 +75,9 @@ module GC
   #  call-seq:
   #    GC.stress = flag          -> flag
   #
-  #  Updates the GC stress mode.
+  #  Updates the \GC stress mode.
   #
-  #  When stress mode is enabled, the GC is invoked at every GC opportunity:
+  #  When stress mode is enabled, the \GC is invoked at every \GC opportunity:
   #  all memory and object allocations.
   #
   #  Enabling stress mode will degrade performance, it is only for debugging.
@@ -114,9 +93,9 @@ module GC
   #  call-seq:
   #     GC.count -> Integer
   #
-  #  The number of times GC occurred.
+  #  The number of times \GC occurred.
   #
-  #  It returns the number of times GC occurred since the process started.
+  #  It returns the number of times \GC occurred since the process started.
   def self.count
     Primitive.gc_count
   end
@@ -126,12 +105,12 @@ module GC
   #     GC.stat(hash) -> Hash
   #     GC.stat(:key) -> Numeric
   #
-  #  Returns a Hash containing information about the GC.
+  #  Returns a Hash containing information about the \GC.
   #
   #  The contents of the hash are implementation specific and may change in
   #  the future without notice.
   #
-  #  The hash includes information about internal statistics about GC such as:
+  #  The hash includes information about internal statistics about \GC such as:
   #
   #  [count]
   #    The total number of garbage collections ran since application start
@@ -144,7 +123,7 @@ module GC
   #    The number of pages that can fit into the buffer that holds references to
   #    all pages
   #  [heap_allocatable_pages]
-  #    The total number of pages the application could allocate without additional GC
+  #    The total number of pages the application could allocate without additional \GC
   #  [heap_available_slots]
   #    The total number of slots in all `:heap_allocated_pages`
   #  [heap_live_slots]
@@ -154,7 +133,7 @@ module GC
   #  [heap_final_slots]
   #    The total number of slots with pending finalizers to be run
   #  [heap_marked_slots]
-  #    The total number of objects marked in the last GC
+  #    The total number of objects marked in the last \GC
   #  [heap_eden_pages]
   #    The total number of pages which contain at least one live slot
   #  [heap_tomb_pages]
@@ -168,9 +147,9 @@ module GC
   #  [total_freed_objects]
   #    The cumulative number of objects freed since application start
   #  [malloc_increase_bytes]
-  #    Amount of memory allocated on the heap for objects. Decreased by any GC
+  #    Amount of memory allocated on the heap for objects. Decreased by any \GC
   #  [malloc_increase_bytes_limit]
-  #    When `:malloc_increase_bytes` crosses this limit, GC is triggered
+  #    When `:malloc_increase_bytes` crosses this limit, \GC is triggered
   #  [minor_gc_count]
   #    The total number of minor garbage collections run since process start
   #  [major_gc_count]
@@ -186,15 +165,15 @@ module GC
   #    The total number of objects without write barriers
   #  [remembered_wb_unprotected_objects_limit]
   #    When `:remembered_wb_unprotected_objects` crosses this limit,
-  #    major GC is triggered
+  #    major \GC is triggered
   #  [old_objects]
   #    Number of live, old objects which have survived at least 3 garbage collections
   #  [old_objects_limit]
-  #    When `:old_objects` crosses this limit, major GC is triggered
+  #    When `:old_objects` crosses this limit, major \GC is triggered
   #  [oldmalloc_increase_bytes]
-  #    Amount of memory allocated on the heap for objects. Decreased by major GC
+  #    Amount of memory allocated on the heap for objects. Decreased by major \GC
   #  [oldmalloc_increase_bytes_limit]
-  #    When `:old_malloc_increase_bytes` crosses this limit, major GC is triggered
+  #    When `:old_malloc_increase_bytes` crosses this limit, major \GC is triggered
   #
   #  If the optional argument, hash, is given,
   #  it is overwritten and returned.
@@ -212,7 +191,7 @@ module GC
   #    GC.stat_heap(heap_name, hash) -> Hash
   #    GC.stat_heap(heap_name, :key) -> Numeric
   #
-  # Returns information for memory pools in the GC.
+  # Returns information for memory pools in the \GC.
   #
   # If the first optional argument, +heap_name+, is passed in and not +nil+, it
   # returns a +Hash+ containing information about the particular memory pool.
@@ -239,12 +218,12 @@ module GC
     Primitive.gc_stat_heap heap_name, hash_or_key
   end
 
-  #  call-seq:
-  #     GC.latest_gc_info -> {:gc_by=>:newobj}
+  # call-seq:
+  #     GC.latest_gc_info -> hash
   #     GC.latest_gc_info(hash) -> hash
   #     GC.latest_gc_info(:major_by) -> :malloc
   #
-  #  Returns information about the most recent garbage collection.
+  # Returns information about the most recent garbage collection.
   #
   # If the optional argument, hash, is given,
   # it is overwritten and returned.
@@ -253,69 +232,32 @@ module GC
     Primitive.gc_latest_gc_info hash_or_key
   end
 
-  #  call-seq:
-  #     GC.latest_compact_info -> {:considered=>{:T_CLASS=>11}, :moved=>{:T_CLASS=>11}}
-  #
-  #  Returns information about object moved in the most recent GC compaction.
-  #
-  # The returned hash has two keys :considered and :moved.  The hash for
-  # :considered lists the number of objects that were considered for movement
-  # by the compactor, and the :moved hash lists the number of objects that
-  # were actually moved.  Some objects can't be moved (maybe they were pinned)
-  # so these numbers can be used to calculate compaction efficiency.
-  def self.latest_compact_info
-    Primitive.gc_compact_stats
-  end
-
-  #  call-seq:
-  #     GC.compact
-  #
-  # This function compacts objects together in Ruby's heap.  It eliminates
-  # unused space (or fragmentation) in the heap by moving objects in to that
-  # unused space.  This function returns a hash which contains statistics about
-  # which objects were moved.  See `GC.latest_gc_info` for details about
-  # compaction statistics.
-  #
-  # This method is implementation specific and not expected to be implemented
-  # in any implementation besides MRI.
-  def self.compact
-    Primitive.gc_compact
+  if respond_to?(:compact)
+    # call-seq:
+    #    GC.verify_compaction_references(toward: nil, double_heap: false) -> hash
+    #
+    # Verify compaction reference consistency.
+    #
+    # This method is implementation specific.  During compaction, objects that
+    # were moved are replaced with T_MOVED objects.  No object should have a
+    # reference to a T_MOVED object after compaction.
+    #
+    # This function expands the heap to ensure room to move all objects,
+    # compacts the heap to make sure everything moves, updates all references,
+    # then performs a full \GC.  If any object contains a reference to a T_MOVED
+    # object, that object should be pushed on the mark stack, and will
+    # make a SEGV.
+    def self.verify_compaction_references(toward: nil, double_heap: false, expand_heap: false)
+      Primitive.gc_verify_compaction_references(double_heap, expand_heap, toward == :empty)
+    end
   end
 
   # call-seq:
-  #    GC.verify_compaction_references(toward: nil, double_heap: false) -> hash
-  #
-  # Verify compaction reference consistency.
-  #
-  # This method is implementation specific.  During compaction, objects that
-  # were moved are replaced with T_MOVED objects.  No object should have a
-  # reference to a T_MOVED object after compaction.
-  #
-  # This function doubles the heap to ensure room to move all objects,
-  # compacts the heap to make sure everything moves, updates all references,
-  # then performs a full GC.  If any object contains a reference to a T_MOVED
-  # object, that object should be pushed on the mark stack, and will
-  # make a SEGV.
-  def self.verify_compaction_references(toward: nil, double_heap: false)
-    Primitive.gc_verify_compaction_references(double_heap, toward == :empty)
-  end
-
-  # call-seq:
-  #     GC.using_rvargc? -> true or false
-  #
-  # Returns true if using experimental feature Variable Width Allocation, false
-  # otherwise.
-  def self.using_rvargc? # :nodoc:
-    GC::INTERNAL_CONSTANTS[:SIZE_POOL_COUNT] > 1
-  end
-
-
-  # call-seq:
   #    GC.measure_total_time = true/false
   #
-  # Enable to measure GC time.
+  # Enable to measure \GC time.
   # You can get the result with <tt>GC.stat(:time)</tt>.
-  # Note that GC time measurement can cause some performance overhead.
+  # Note that \GC time measurement can cause some performance overhead.
   def self.measure_total_time=(flag)
     Primitive.cstmt! %{
       rb_objspace.flags.measure_gc = RTEST(flag) ? TRUE : FALSE;
@@ -337,7 +279,7 @@ module GC
   # call-seq:
   #    GC.total_time -> int
   #
-  # Return measured GC total time in nano seconds.
+  # Return measured \GC total time in nano seconds.
   def self.total_time
     Primitive.cexpr! %{
       ULL2NUM(rb_objspace.profile.total_time_ns)
diff --git a/gem_prelude.rb b/gem_prelude.rb
index 94ada316aa..f382021ca3 100644
--- a/gem_prelude.rb
+++ b/gem_prelude.rb
@@ -17,3 +17,10 @@ begin
 rescue LoadError
   warn "`did_you_mean' was not loaded."
 end if defined?(DidYouMean)
+
+begin
+  require 'syntax_suggest/core_ext'
+rescue LoadError
+  warn "`syntax_suggest' was not loaded."
+end if defined?(SyntaxSuggest)
+
diff --git a/gems/bundled_gems b/gems/bundled_gems
index 04c62954eb..d37d869d41 100644
--- a/gems/bundled_gems
+++ b/gems/bundled_gems
@@ -1,16 +1,16 @@
 # gem-name version-to-bundle repository-url [optional-commit-hash-to-test-or-defaults-to-v-version]
-minitest 5.15.0 https://github.com/seattlerb/minitest
-power_assert 2.0.1 https://github.com/ruby/power_assert
-rake 13.0.6 https://github.com/ruby/rake
-test-unit 3.5.3 https://github.com/test-unit/test-unit 3.5.3
-rexml 3.2.5 https://github.com/ruby/rexml
-rss 0.2.9 https://github.com/ruby/rss 0.2.9
-net-ftp 0.1.3 https://github.com/ruby/net-ftp
-net-imap 0.2.3 https://github.com/ruby/net-imap
-net-pop 0.1.1 https://github.com/ruby/net-pop
-net-smtp 0.3.1 https://github.com/ruby/net-smtp
-matrix 0.4.2 https://github.com/ruby/matrix
-prime 0.1.2 https://github.com/ruby/prime
-rbs 2.3.2 https://github.com/ruby/rbs
-typeprof 0.21.2 https://github.com/ruby/typeprof 8577943c042145af4c87914fa323c0a854da2e6d
-debug 1.5.0 https://github.com/ruby/debug 1fce2583d1e71419998507898ba5f7eea815133f
+minitest        5.25.1  https://github.com/seattlerb/minitest
+power_assert    2.0.3   https://github.com/ruby/power_assert
+rake            13.0.6  https://github.com/ruby/rake
+test-unit       3.5.7   https://github.com/test-unit/test-unit
+rexml           3.3.9   https://github.com/ruby/rexml
+rss             0.3.1   https://github.com/ruby/rss
+net-ftp         0.2.1   https://github.com/ruby/net-ftp
+net-imap        0.3.9   https://github.com/ruby/net-imap
+net-pop         0.1.2   https://github.com/ruby/net-pop
+net-smtp        0.3.4   https://github.com/ruby/net-smtp
+matrix          0.4.2   https://github.com/ruby/matrix
+prime           0.1.2   https://github.com/ruby/prime
+rbs             2.8.2   https://github.com/ruby/rbs
+typeprof        0.21.3  https://github.com/ruby/typeprof
+debug           1.7.1   https://github.com/ruby/debug
diff --git a/gems/lib/core_assertions.rb b/gems/lib/core_assertions.rb
new file mode 100644
index 0000000000..7334063885
--- /dev/null
+++ b/gems/lib/core_assertions.rb
@@ -0,0 +1 @@
+require_relative "../../tool/lib/core_assertions.rb"
diff --git a/gems/lib/envutil.rb b/gems/lib/envutil.rb
new file mode 100644
index 0000000000..d684c22cf2
--- /dev/null
+++ b/gems/lib/envutil.rb
@@ -0,0 +1 @@
+require_relative "../../tool/lib/envutil.rb"
diff --git a/tool/dummy-rake-compiler/rake/extensiontask.rb b/gems/lib/rake/extensiontask.rb
index 62b7ff8018..fdbe8d8874 100644
--- a/tool/dummy-rake-compiler/rake/extensiontask.rb
+++ b/gems/lib/rake/extensiontask.rb
@@ -1,8 +1,11 @@
+require "rake/tasklib" unless defined?(Rake::TaskLib)
+
 module Rake
   class ExtensionTask < TaskLib
     def initialize(...)
-      task :compile do
+      task :compile do |args|
         puts "Dummy `compile` task defined in #{__FILE__}"
+        puts "#{args.name} => #{args.prereqs.join(' ')}"
       end
     end
   end
diff --git a/goruby.c b/goruby.c
index c90fc97b0a..5d45277207 100644
--- a/goruby.c
+++ b/goruby.c
@@ -37,21 +37,21 @@ goruby_options(int argc, char **argv)
     void *ret;
 
     if ((isatty(0) && isatty(1) && isatty(2)) && (pipe(rw) == 0)) {
-	ssize_t n;
-	infd = dup(0);
-	if (infd < 0) {
-	    close(rw[0]);
-	    close(rw[1]);
-	    goto no_irb;
-	}
-	dup2(rw[0], 0);
-	close(rw[0]);
-	n = write(rw[1], cmd, sizeof(cmd) - 1);
-	close(rw[1]);
-	ret = n > 0 ? ruby_options(argc, argv) : NULL;
-	dup2(infd, 0);
-	close(infd);
-	return ret;
+        ssize_t n;
+        infd = dup(0);
+        if (infd < 0) {
+            close(rw[0]);
+            close(rw[1]);
+            goto no_irb;
+        }
+        dup2(rw[0], 0);
+        close(rw[0]);
+        n = write(rw[1], cmd, sizeof(cmd) - 1);
+        close(rw[1]);
+        ret = n > 0 ? ruby_options(argc, argv) : NULL;
+        dup2(infd, 0);
+        close(infd);
+        return ret;
     }
   no_irb:
     return ruby_options(argc, argv);
@@ -62,7 +62,7 @@ goruby_run_node(void *arg)
 {
     int state;
     if (NIL_P(rb_protect(init_golf, Qtrue, &state))) {
-	return state == EXIT_SUCCESS ? EXIT_FAILURE : state;
+        return state == EXIT_SUCCESS ? EXIT_FAILURE : state;
     }
     return ruby_run_node(arg);
 }
diff --git a/hash.c b/hash.c
index da85fd35c6..d2dce30624 100644
--- a/hash.c
+++ b/hash.c
@@ -28,6 +28,7 @@
 #include "internal.h"
 #include "internal/array.h"
 #include "internal/bignum.h"
+#include "internal/basic_operators.h"
 #include "internal/class.h"
 #include "internal/cont.h"
 #include "internal/error.h"
@@ -35,6 +36,7 @@
 #include "internal/object.h"
 #include "internal/proc.h"
 #include "internal/symbol.h"
+#include "internal/thread.h"
 #include "internal/time.h"
 #include "internal/vm.h"
 #include "probes.h"
@@ -92,9 +94,11 @@ rb_hash_freeze(VALUE hash)
 VALUE rb_cHash;
 
 static VALUE envtbl;
-static ID id_hash, id_default, id_flatten_bang;
+static ID id_hash, id_flatten_bang;
 static ID id_hash_iter_lev;
 
+#define id_default idDefault
+
 VALUE
 rb_hash_set_ifnone(VALUE hash, VALUE ifnone)
 {
@@ -107,12 +111,12 @@ rb_any_cmp(VALUE a, VALUE b)
 {
     if (a == b) return 0;
     if (RB_TYPE_P(a, T_STRING) && RBASIC(a)->klass == rb_cString &&
-	RB_TYPE_P(b, T_STRING) && RBASIC(b)->klass == rb_cString) {
-	return rb_str_hash_cmp(a, b);
+        RB_TYPE_P(b, T_STRING) && RBASIC(b)->klass == rb_cString) {
+        return rb_str_hash_cmp(a, b);
     }
-    if (a == Qundef || b == Qundef) return -1;
+    if (UNDEF_P(a) || UNDEF_P(b)) return -1;
     if (SYMBOL_P(a) && SYMBOL_P(b)) {
-	return a != b;
+        return a != b;
     }
 
     return !rb_eql(a, b);
@@ -155,7 +159,7 @@ any_hash(VALUE a, st_index_t (*other_func)(VALUE))
 
     switch (TYPE(a)) {
       case T_SYMBOL:
-	if (STATIC_SYM_P(a)) {
+        if (STATIC_SYM_P(a)) {
             hnum = a >> (RUBY_SPECIAL_SHIFT + ID_SCOPE_SHIFT);
             hnum = rb_hash_start(hnum);
         }
@@ -167,25 +171,25 @@ any_hash(VALUE a, st_index_t (*other_func)(VALUE))
       case T_TRUE:
       case T_FALSE:
       case T_NIL:
-	hnum = rb_objid_hash((st_index_t)a);
+        hnum = rb_objid_hash((st_index_t)a);
         break;
       case T_STRING:
-	hnum = rb_str_hash(a);
+        hnum = rb_str_hash(a);
         break;
       case T_BIGNUM:
-	hval = rb_big_hash(a);
-	hnum = FIX2LONG(hval);
+        hval = rb_big_hash(a);
+        hnum = FIX2LONG(hval);
         break;
       case T_FLOAT: /* prevent pathological behavior: [Bug #10761] */
-	hnum = rb_dbl_long_hash(rb_float_value(a));
+        hnum = rb_dbl_long_hash(rb_float_value(a));
         break;
       default:
-	hnum = other_func(a);
+        hnum = other_func(a);
     }
     if ((SIGNED_VALUE)hnum > 0)
-	hnum &= FIXNUM_MAX;
+        hnum &= FIXNUM_MAX;
     else
-	hnum |= FIXNUM_MIN;
+        hnum |= FIXNUM_MIN;
     return (long)hnum;
 }
 
@@ -194,8 +198,8 @@ obj_any_hash(VALUE obj)
 {
     VALUE hval = rb_check_funcall_basic_kw(obj, id_hash, rb_mKernel, 0, 0, 0);
 
-    if (hval == Qundef) {
-        hval = rb_exec_recursive_outer(hash_recursive, obj, 0);
+    if (UNDEF_P(hval)) {
+        hval = rb_exec_recursive_outer_mid(hash_recursive, obj, 0, id_hash);
     }
 
     while (!FIXNUM_P(hval)) {
@@ -217,7 +221,7 @@ obj_any_hash(VALUE obj)
     return FIX2LONG(hval);
 }
 
-static st_index_t
+st_index_t
 rb_any_hash(VALUE a)
 {
     return any_hash(a, obj_any_hash);
@@ -303,6 +307,19 @@ objid_hash(VALUE obj)
  *
  * Certain core classes such as Integer use built-in hash calculations and
  * do not call the #hash method when used as a hash key.
+ *
+ * When implementing your own #hash based on multiple values, the best
+ * practice is to combine the class and any values using the hash code of an
+ * array:
+ *
+ * For example:
+ *
+ *   def hash
+ *     [self.class, a, b, c].hash
+ *   end
+ *
+ * The reason for this is that the Array#hash method already has logic for
+ * safely and efficiently combining multiple hash values.
  *--
  * \private
  *++
@@ -344,6 +361,9 @@ const struct st_hash_type rb_hashtype_ident = {
     rb_ident_hash,
 };
 
+#define RHASH_IDENTHASH_P(hash) (RHASH_TYPE(hash) == &identhash)
+#define RHASH_STRING_KEY_P(hash, key) (!RHASH_IDENTHASH_P(hash) && (rb_obj_class(key) == rb_cString))
+
 typedef st_index_t st_hash_t;
 
 /*
@@ -423,7 +443,7 @@ ar_cleared_entry(VALUE hash, unsigned int index)
          * so you need to check key == Qundef
          */
         ar_table_pair *pair = RHASH_AR_TABLE_REF(hash, index);
-        return pair->key == Qundef;
+        return UNDEF_P(pair->key);
     }
     else {
         return FALSE;
@@ -503,8 +523,8 @@ hash_verify_(VALUE hash, const char *file, int line)
                 ar_table_pair *pair = RHASH_AR_TABLE_REF(hash, i);
                 k = pair->key;
                 v = pair->val;
-                HASH_ASSERT(k != Qundef);
-                HASH_ASSERT(v != Qundef);
+                HASH_ASSERT(!UNDEF_P(k));
+                HASH_ASSERT(!UNDEF_P(v));
                 n++;
             }
         }
@@ -750,31 +770,39 @@ ar_free_and_clear_table(VALUE hash)
     HASH_ASSERT(RHASH_TRANSIENT_P(hash) == 0);
 }
 
-static void
-ar_try_convert_table(VALUE hash)
-{
-    if (!RHASH_AR_TABLE_P(hash)) return;
-
-    const unsigned size = RHASH_AR_TABLE_SIZE(hash);
+void rb_st_add_direct_with_hash(st_table *tab, st_data_t key, st_data_t value, st_hash_t hash); // st.c
 
-    st_table *new_tab;
-    st_index_t i;
+enum ar_each_key_type {
+    ar_each_key_copy,
+    ar_each_key_cmp,
+    ar_each_key_insert,
+};
 
-    if (size < RHASH_AR_TABLE_MAX_SIZE) {
-        return;
+static inline int
+ar_each_key(ar_table *ar, int max, enum ar_each_key_type type, st_data_t *dst_keys, st_table *new_tab, st_hash_t *hashes)
+{
+    for (int i = 0; i < max; i++) {
+        ar_table_pair *pair = &ar->pairs[i];
+
+        switch (type) {
+          case ar_each_key_copy:
+            dst_keys[i] = pair->key;
+            break;
+          case ar_each_key_cmp:
+            if (dst_keys[i] != pair->key) return 1;
+            break;
+          case ar_each_key_insert:
+            if (UNDEF_P(pair->key)) continue; // deleted entry
+            rb_st_add_direct_with_hash(new_tab, pair->key, pair->val, hashes[i]);
+            break;
+        }
     }
 
-    new_tab = st_init_table_with_size(&objhash, size * 2);
-
-    for (i = 0; i < RHASH_AR_TABLE_MAX_BOUND; i++) {
-        ar_table_pair *pair = RHASH_AR_TABLE_REF(hash, i);
-        st_add_direct(new_tab, pair->key, pair->val);
-    }
-    ar_free_and_clear_table(hash);
-    RHASH_ST_TABLE_SET(hash, new_tab);
-    return;
+    return 0;
 }
 
+
+
 static st_table *
 ar_force_convert_table(VALUE hash, const char *file, int line)
 {
@@ -785,22 +813,32 @@ ar_force_convert_table(VALUE hash, const char *file, int line)
     }
 
     if (RHASH_AR_TABLE(hash)) {
-        unsigned i, bound = RHASH_AR_TABLE_BOUND(hash);
+        ar_table *ar = RHASH_AR_TABLE(hash);
+        st_hash_t hashes[RHASH_AR_TABLE_MAX_SIZE];
+        unsigned int bound, size;
+
+        // prepare hash values
+        do {
+            st_data_t keys[RHASH_AR_TABLE_MAX_SIZE];
+            bound = RHASH_AR_TABLE_BOUND(hash);
+            size = RHASH_AR_TABLE_SIZE(hash);
+            ar_each_key(ar, bound, ar_each_key_copy, keys, NULL, NULL);
+
+            for (unsigned int i = 0; i < bound; i++) {
+                // do_hash calls #hash method and it can modify hash object
+                hashes[i] = UNDEF_P(keys[i]) ? 0 : ar_do_hash(keys[i]);
+            }
 
-#if defined(RHASH_CONVERT_TABLE_DEBUG) && RHASH_CONVERT_TABLE_DEBUG
-        rb_obj_info_dump(hash);
-        fprintf(stderr, "force_convert: %s:%d\n", file, line);
-        RB_DEBUG_COUNTER_INC(obj_hash_force_convert);
-#endif
+            // check if modified
+            if (UNLIKELY(!RHASH_AR_TABLE_P(hash))) return RHASH_ST_TABLE(hash);
+            if (UNLIKELY(RHASH_AR_TABLE_BOUND(hash) != bound)) continue;
+            if (UNLIKELY(ar_each_key(ar, bound, ar_each_key_cmp, keys, NULL, NULL))) continue;
+        } while (0);
 
-        new_tab = st_init_table_with_size(&objhash, RHASH_AR_TABLE_SIZE(hash));
 
-        for (i = 0; i < bound; i++) {
-            if (ar_cleared_entry(hash, i)) continue;
-
-            ar_table_pair *pair = RHASH_AR_TABLE_REF(hash, i);
-            st_add_direct(new_tab, pair->key, pair->val);
-        }
+        // make st
+        new_tab = st_init_table_with_size(&objhash, size);
+        ar_each_key(ar, bound, ar_each_key_insert, NULL, new_tab, hashes);
         ar_free_and_clear_table(hash);
     }
     else {
@@ -949,7 +987,7 @@ ar_foreach(VALUE hash, st_foreach_callback_func *func, st_data_t arg)
 
 static int
 ar_foreach_check(VALUE hash, st_foreach_check_callback_func *func, st_data_t arg,
-                     st_data_t never)
+                 st_data_t never)
 {
     if (RHASH_AR_TABLE_SIZE(hash) > 0) {
         unsigned i, ret = 0, bound = RHASH_AR_TABLE_BOUND(hash);
@@ -970,13 +1008,13 @@ ar_foreach_check(VALUE hash, st_foreach_check_callback_func *func, st_data_t arg
 
             switch (retval) {
               case ST_CHECK: {
-                  pair = RHASH_AR_TABLE_REF(hash, i);
-                  if (pair->key == never) break;
-                  ret = ar_find_entry_hint(hash, hint, key);
-                  if (ret == RHASH_AR_TABLE_MAX_BOUND) {
-                      retval = (*func)(0, 0, arg, 1);
-                      return 2;
-                  }
+                pair = RHASH_AR_TABLE_REF(hash, i);
+                if (pair->key == never) break;
+                ret = ar_find_entry_hint(hash, hint, key);
+                if (ret == RHASH_AR_TABLE_MAX_BOUND) {
+                    retval = (*func)(0, 0, arg, 1);
+                    return 2;
+                }
               }
               case ST_CONTINUE:
                 break;
@@ -984,11 +1022,11 @@ ar_foreach_check(VALUE hash, st_foreach_check_callback_func *func, st_data_t arg
               case ST_REPLACE:
                 return 0;
               case ST_DELETE: {
-                  if (!ar_cleared_entry(hash, i)) {
-                      ar_clear_entry(hash, i);
-                      RHASH_AR_TABLE_SIZE_DEC(hash);
-                  }
-                  break;
+                if (!ar_cleared_entry(hash, i)) {
+                    ar_clear_entry(hash, i);
+                    RHASH_AR_TABLE_SIZE_DEC(hash);
+                }
+                break;
               }
             }
         }
@@ -1305,7 +1343,7 @@ foreach_safe_i(st_data_t key, st_data_t value, st_data_t args, int error)
     if (error) return ST_STOP;
     status = (*arg->func)(key, value, arg->arg);
     if (status == ST_CONTINUE) {
-	return ST_CHECK;
+        return ST_CHECK;
     }
     return status;
 }
@@ -1319,7 +1357,7 @@ st_foreach_safe(st_table *table, st_foreach_func *func, st_data_t a)
     arg.func = (st_foreach_func *)func;
     arg.arg = a;
     if (st_foreach_check(table, foreach_safe_i, (st_data_t)&arg, 0)) {
-	rb_raise(rb_eRuntimeError, "hash modified during iteration");
+        rb_raise(rb_eRuntimeError, "hash modified during iteration");
     }
 }
 
@@ -1332,15 +1370,8 @@ struct hash_foreach_arg {
 };
 
 static int
-hash_ar_foreach_iter(st_data_t key, st_data_t value, st_data_t argp, int error)
+hash_iter_status_check(int status)
 {
-    struct hash_foreach_arg *arg = (struct hash_foreach_arg *)argp;
-    int status;
-
-    if (error) return ST_STOP;
-    status = (*arg->func)((VALUE)key, (VALUE)value, arg->arg);
-    /* TODO: rehash check? rb_raise(rb_eRuntimeError, "rehash occurred during iteration"); */
-
     switch (status) {
       case ST_DELETE:
         return ST_DELETE;
@@ -1349,31 +1380,38 @@ hash_ar_foreach_iter(st_data_t key, st_data_t value, st_data_t argp, int error)
       case ST_STOP:
         return ST_STOP;
     }
+
     return ST_CHECK;
 }
 
 static int
+hash_ar_foreach_iter(st_data_t key, st_data_t value, st_data_t argp, int error)
+{
+    struct hash_foreach_arg *arg = (struct hash_foreach_arg *)argp;
+
+    if (error) return ST_STOP;
+
+    int status = (*arg->func)((VALUE)key, (VALUE)value, arg->arg);
+    /* TODO: rehash check? rb_raise(rb_eRuntimeError, "rehash occurred during iteration"); */
+
+    return hash_iter_status_check(status);
+}
+
+static int
 hash_foreach_iter(st_data_t key, st_data_t value, st_data_t argp, int error)
 {
     struct hash_foreach_arg *arg = (struct hash_foreach_arg *)argp;
-    int status;
-    st_table *tbl;
 
     if (error) return ST_STOP;
-    tbl = RHASH_ST_TABLE(arg->hash);
-    status = (*arg->func)((VALUE)key, (VALUE)value, arg->arg);
+
+    st_table *tbl = RHASH_ST_TABLE(arg->hash);
+    int status = (*arg->func)((VALUE)key, (VALUE)value, arg->arg);
+
     if (RHASH_ST_TABLE(arg->hash) != tbl) {
-    	rb_raise(rb_eRuntimeError, "rehash occurred during iteration");
-    }
-    switch (status) {
-      case ST_DELETE:
-	return ST_DELETE;
-      case ST_CONTINUE:
-	break;
-      case ST_STOP:
-	return ST_STOP;
+        rb_raise(rb_eRuntimeError, "rehash occurred during iteration");
     }
-    return ST_CHECK;
+
+    return hash_iter_status_check(status);
 }
 
 static int
@@ -1392,13 +1430,19 @@ iter_lev_in_ivar_set(VALUE hash, int lev)
     rb_ivar_set_internal(hash, id_hash_iter_lev, INT2FIX(lev));
 }
 
-static int
+static inline int
 iter_lev_in_flags(VALUE hash)
 {
     unsigned int u = (unsigned int)((RBASIC(hash)->flags >> RHASH_LEV_SHIFT) & RHASH_LEV_MAX);
     return (int)u;
 }
 
+static inline void
+iter_lev_in_flags_set(VALUE hash, int lev)
+{
+    RBASIC(hash)->flags = ((RBASIC(hash)->flags & ~RHASH_LEV_MASK) | ((VALUE)lev << RHASH_LEV_SHIFT));
+}
+
 static int
 RHASH_ITER_LEV(VALUE hash)
 {
@@ -1422,7 +1466,7 @@ hash_iter_lev_inc(VALUE hash)
     }
     else {
         lev += 1;
-        RBASIC(hash)->flags = ((RBASIC(hash)->flags & ~RHASH_LEV_MASK) | ((VALUE)lev << RHASH_LEV_SHIFT));
+        iter_lev_in_flags_set(hash, lev);
         if (lev == RHASH_LEV_MAX) {
             iter_lev_in_ivar_set(hash, lev);
         }
@@ -1440,7 +1484,7 @@ hash_iter_lev_dec(VALUE hash)
     }
     else {
         HASH_ASSERT(lev > 0);
-        RBASIC(hash)->flags = ((RBASIC(hash)->flags & ~RHASH_LEV_MASK) | ((lev-1) << RHASH_LEV_SHIFT));
+        iter_lev_in_flags_set(hash, lev - 1);
     }
 }
 
@@ -1519,6 +1563,16 @@ rb_hash_foreach(VALUE hash, rb_foreach_func *func, VALUE farg)
     hash_verify(hash);
 }
 
+void rb_st_compact_table(st_table *tab);
+
+static void
+compact_after_delete(VALUE hash)
+{
+    if (RHASH_ITER_LEV(hash) == 0 && RHASH_ST_TABLE_P(hash)) {
+        rb_st_compact_table(RHASH_ST_TABLE(hash));
+    }
+}
+
 static VALUE
 hash_alloc_flags(VALUE klass, VALUE flags, VALUE ifnone)
 {
@@ -1575,6 +1629,12 @@ rb_hash_new_with_size(st_index_t size)
     return ret;
 }
 
+VALUE
+rb_hash_new_capa(long capa)
+{
+    return rb_hash_new_with_size((st_index_t)capa);
+}
+
 static VALUE
 hash_copy(VALUE ret, VALUE hash)
 {
@@ -1685,7 +1745,7 @@ rb_hash_stlike_update(VALUE hash, st_data_t key, st_update_callback_func *func,
     if (RHASH_AR_TABLE_P(hash)) {
         int result = ar_update(hash, key, func, arg);
         if (result == -1) {
-            ar_try_convert_table(hash);
+            ar_force_convert_table(hash, __FILE__, __LINE__);
         }
         else {
             return result;
@@ -1755,12 +1815,12 @@ static void
 set_proc_default(VALUE hash, VALUE proc)
 {
     if (rb_proc_lambda_p(proc)) {
-	int n = rb_proc_arity(proc);
+        int n = rb_proc_arity(proc);
 
-	if (n != 2 && (n >= 0 || n < -3)) {
-	    if (n < 0) n = -n-1;
-	    rb_raise(rb_eTypeError, "default_proc takes two arguments (2 for %d)", n);
-	}
+        if (n != 2 && (n >= 0 || n < -3)) {
+            if (n < 0) n = -n-1;
+            rb_raise(rb_eTypeError, "default_proc takes two arguments (2 for %d)", n);
+        }
     }
 
     FL_SET_RAW(hash, RHASH_PROC_DEFAULT);
@@ -1805,14 +1865,14 @@ rb_hash_initialize(int argc, VALUE *argv, VALUE hash)
 
     rb_hash_modify(hash);
     if (rb_block_given_p()) {
-	rb_check_arity(argc, 0, 0);
-	ifnone = rb_block_proc();
-	SET_PROC_DEFAULT(hash, ifnone);
+        rb_check_arity(argc, 0, 0);
+        ifnone = rb_block_proc();
+        SET_PROC_DEFAULT(hash, ifnone);
     }
     else {
-	rb_check_arity(argc, 0, 1);
-	ifnone = argc == 0 ? Qnil : argv[0];
-	RHASH_SET_IFNONE(hash, ifnone);
+        rb_check_arity(argc, 0, 1);
+        ifnone = argc == 0 ? Qnil : argv[0];
+        RHASH_SET_IFNONE(hash, ifnone);
     }
 
     return hash;
@@ -1860,42 +1920,42 @@ rb_hash_s_create(int argc, VALUE *argv, VALUE klass)
 
     if (argc == 1) {
         tmp = rb_hash_s_try_convert(Qnil, argv[0]);
-	if (!NIL_P(tmp)) {
-	    hash = hash_alloc(klass);
+        if (!NIL_P(tmp)) {
+            hash = hash_alloc(klass);
             hash_copy(hash, tmp);
-	    return hash;
-	}
-
-	tmp = rb_check_array_type(argv[0]);
-	if (!NIL_P(tmp)) {
-	    long i;
-
-	    hash = hash_alloc(klass);
-	    for (i = 0; i < RARRAY_LEN(tmp); ++i) {
-		VALUE e = RARRAY_AREF(tmp, i);
-		VALUE v = rb_check_array_type(e);
-		VALUE key, val = Qnil;
-
-		if (NIL_P(v)) {
-		    rb_raise(rb_eArgError, "wrong element type %s at %ld (expected array)",
-			     rb_builtin_class_name(e), i);
-		}
-		switch (RARRAY_LEN(v)) {
-		  default:
-		    rb_raise(rb_eArgError, "invalid number of elements (%ld for 1..2)",
-			     RARRAY_LEN(v));
-		  case 2:
-		    val = RARRAY_AREF(v, 1);
-		  case 1:
-		    key = RARRAY_AREF(v, 0);
-		    rb_hash_aset(hash, key, val);
-		}
-	    }
-	    return hash;
-	}
+            return hash;
+        }
+
+        tmp = rb_check_array_type(argv[0]);
+        if (!NIL_P(tmp)) {
+            long i;
+
+            hash = hash_alloc(klass);
+            for (i = 0; i < RARRAY_LEN(tmp); ++i) {
+                VALUE e = RARRAY_AREF(tmp, i);
+                VALUE v = rb_check_array_type(e);
+                VALUE key, val = Qnil;
+
+                if (NIL_P(v)) {
+                    rb_raise(rb_eArgError, "wrong element type %s at %ld (expected array)",
+                             rb_builtin_class_name(e), i);
+                }
+                switch (RARRAY_LEN(v)) {
+                  default:
+                    rb_raise(rb_eArgError, "invalid number of elements (%ld for 1..2)",
+                             RARRAY_LEN(v));
+                  case 2:
+                    val = RARRAY_AREF(v, 1);
+                  case 1:
+                    key = RARRAY_AREF(v, 0);
+                    rb_hash_aset(hash, key, val);
+                }
+            }
+            return hash;
+        }
     }
     if (argc % 2 != 0) {
-	rb_raise(rb_eArgError, "odd number of arguments for Hash");
+        rb_raise(rb_eArgError, "odd number of arguments for Hash");
     }
 
     hash = hash_alloc(klass);
@@ -2018,7 +2078,7 @@ rb_hash_rehash(VALUE hash)
     st_table *tbl;
 
     if (RHASH_ITER_LEV(hash) > 0) {
-	rb_raise(rb_eRuntimeError, "rehash during iteration");
+        rb_raise(rb_eRuntimeError, "rehash during iteration");
     }
     rb_hash_modify_check(hash);
     if (RHASH_AR_TABLE_P(hash)) {
@@ -2050,17 +2110,31 @@ call_default_proc(VALUE proc, VALUE hash, VALUE key)
     return rb_proc_call_with_block(proc, 2, args, Qnil);
 }
 
+static bool
+rb_hash_default_unredefined(VALUE hash)
+{
+    VALUE klass = RBASIC_CLASS(hash);
+    if (LIKELY(klass == rb_cHash)) {
+        return !!BASIC_OP_UNREDEFINED_P(BOP_DEFAULT, HASH_REDEFINED_OP_FLAG);
+    }
+    else {
+        return LIKELY(rb_method_basic_definition_p(klass, id_default));
+    }
+}
+
 VALUE
 rb_hash_default_value(VALUE hash, VALUE key)
 {
-    if (LIKELY(rb_method_basic_definition_p(CLASS_OF(hash), id_default))) {
-	VALUE ifnone = RHASH_IFNONE(hash);
-        if (!FL_TEST(hash, RHASH_PROC_DEFAULT)) return ifnone;
-	if (key == Qundef) return Qnil;
+    RUBY_ASSERT(RB_TYPE_P(hash, T_HASH));
+
+    if (LIKELY(rb_hash_default_unredefined(hash))) {
+        VALUE ifnone = RHASH_IFNONE(hash);
+        if (LIKELY(!FL_TEST_RAW(hash, RHASH_PROC_DEFAULT))) return ifnone;
+        if (UNDEF_P(key)) return Qnil;
         return call_default_proc(ifnone, hash, key);
     }
     else {
-	return rb_funcall(hash, id_default, 1, key);
+        return rb_funcall(hash, id_default, 1, key);
     }
 }
 
@@ -2164,7 +2238,7 @@ rb_hash_fetch_m(int argc, VALUE *argv, VALUE hash)
 
     block_given = rb_block_given_p();
     if (block_given && argc == 2) {
-	rb_warn("block supersedes default value argument");
+        rb_warn("block supersedes default value argument");
     }
 
     if (hash_stlike_lookup(hash, key, &val)) {
@@ -2222,8 +2296,8 @@ rb_hash_default(int argc, VALUE *argv, VALUE hash)
     rb_check_arity(argc, 0, 1);
     ifnone = RHASH_IFNONE(hash);
     if (FL_TEST(hash, RHASH_PROC_DEFAULT)) {
-	if (argc == 0) return Qnil;
-	return call_default_proc(ifnone, hash, argv[0]);
+        if (argc == 0) return Qnil;
+        return call_default_proc(ifnone, hash, argv[0]);
     }
     return ifnone;
 }
@@ -2265,7 +2339,7 @@ static VALUE
 rb_hash_default_proc(VALUE hash)
 {
     if (FL_TEST(hash, RHASH_PROC_DEFAULT)) {
-	return RHASH_IFNONE(hash);
+        return RHASH_IFNONE(hash);
     }
     return Qnil;
 }
@@ -2291,14 +2365,14 @@ rb_hash_set_default_proc(VALUE hash, VALUE proc)
 
     rb_hash_modify_check(hash);
     if (NIL_P(proc)) {
-	SET_DEFAULT(hash, proc);
-	return proc;
+        SET_DEFAULT(hash, proc);
+        return proc;
     }
     b = rb_check_convert_type_with_id(proc, T_DATA, "Proc", idTo_proc);
     if (NIL_P(b) || !rb_obj_is_proc(b)) {
-	rb_raise(rb_eTypeError,
-		 "wrong default_proc type %s (expected Proc)",
-		 rb_obj_classname(proc));
+        rb_raise(rb_eTypeError,
+                 "wrong default_proc type %s (expected Proc)",
+                 rb_obj_classname(proc));
     }
     proc = b;
     SET_PROC_DEFAULT(hash, proc);
@@ -2311,8 +2385,8 @@ key_i(VALUE key, VALUE value, VALUE arg)
     VALUE *args = (VALUE *)arg;
 
     if (rb_equal(value, args[0])) {
-	args[1] = key;
-	return ST_STOP;
+        args[1] = key;
+        return ST_STOP;
     }
     return ST_CONTINUE;
 }
@@ -2382,11 +2456,11 @@ rb_hash_delete(VALUE hash, VALUE key)
 {
     VALUE deleted_value = rb_hash_delete_entry(hash, key);
 
-    if (deleted_value != Qundef) { /* likely pass */
-	return deleted_value;
+    if (!UNDEF_P(deleted_value)) { /* likely pass */
+        return deleted_value;
     }
     else {
-	return Qnil;
+        return Qnil;
     }
 }
 
@@ -2425,16 +2499,17 @@ rb_hash_delete_m(VALUE hash, VALUE key)
     rb_hash_modify_check(hash);
     val = rb_hash_delete_entry(hash, key);
 
-    if (val != Qundef) {
-	return val;
+    if (!UNDEF_P(val)) {
+        compact_after_delete(hash);
+        return val;
     }
     else {
-	if (rb_block_given_p()) {
-	    return rb_yield(key);
-	}
-	else {
-	    return Qnil;
-	}
+        if (rb_block_given_p()) {
+            return rb_yield(key);
+        }
+        else {
+            return Qnil;
+        }
     }
 }
 
@@ -2474,15 +2549,15 @@ rb_hash_shift(VALUE hash)
 
     rb_hash_modify_check(hash);
     if (RHASH_AR_TABLE_P(hash)) {
-	var.key = Qundef;
-	if (RHASH_ITER_LEV(hash) == 0) {
+        var.key = Qundef;
+        if (RHASH_ITER_LEV(hash) == 0) {
             if (ar_shift(hash, &var.key, &var.val)) {
-		return rb_assoc_new(var.key, var.val);
-	    }
-	}
-	else {
+                return rb_assoc_new(var.key, var.val);
+            }
+        }
+        else {
             rb_hash_foreach(hash, shift_i_safe, (VALUE)&var);
-            if (var.key != Qundef) {
+            if (!UNDEF_P(var.key)) {
                 rb_hash_delete_entry(hash, var.key);
                 return rb_assoc_new(var.key, var.val);
             }
@@ -2496,12 +2571,12 @@ rb_hash_shift(VALUE hash)
             }
         }
         else {
-	    rb_hash_foreach(hash, shift_i_safe, (VALUE)&var);
-	    if (var.key != Qundef) {
-		rb_hash_delete_entry(hash, var.key);
-		return rb_assoc_new(var.key, var.val);
-	    }
-	}
+            rb_hash_foreach(hash, shift_i_safe, (VALUE)&var);
+            if (!UNDEF_P(var.key)) {
+                rb_hash_delete_entry(hash, var.key);
+                return rb_assoc_new(var.key, var.val);
+            }
+        }
     }
     return Qnil;
 }
@@ -2510,8 +2585,8 @@ static int
 delete_if_i(VALUE key, VALUE value, VALUE hash)
 {
     if (RTEST(rb_yield_values(2, key, value))) {
-	rb_hash_modify(hash);
-	return ST_DELETE;
+        rb_hash_modify(hash);
+        return ST_DELETE;
     }
     return ST_CONTINUE;
 }
@@ -2546,6 +2621,7 @@ rb_hash_delete_if(VALUE hash)
     rb_hash_modify_check(hash);
     if (!RHASH_TABLE_EMPTY_P(hash)) {
         rb_hash_foreach(hash, delete_if_i, hash);
+        compact_after_delete(hash);
     }
     return hash;
 }
@@ -2608,7 +2684,8 @@ rb_hash_reject(VALUE hash)
     RETURN_SIZED_ENUMERATOR(hash, 0, 0, hash_enum_size);
     result = hash_dup_with_compare_by_id(hash);
     if (!RHASH_EMPTY_P(hash)) {
-	rb_hash_foreach(result, delete_if_i, result);
+        rb_hash_foreach(result, delete_if_i, result);
+        compact_after_delete(result);
     }
     return result;
 }
@@ -2636,10 +2713,10 @@ rb_hash_slice(int argc, VALUE *argv, VALUE hash)
     result = copy_compare_by_id(rb_hash_new_with_size(argc), hash);
 
     for (i = 0; i < argc; i++) {
-	key = argv[i];
-	value = rb_hash_lookup2(hash, key, Qundef);
-	if (value != Qundef)
-	    rb_hash_aset(result, key, value);
+        key = argv[i];
+        value = rb_hash_lookup2(hash, key, Qundef);
+        if (!UNDEF_P(value))
+            rb_hash_aset(result, key, value);
     }
 
     return result;
@@ -2668,6 +2745,7 @@ rb_hash_except(int argc, VALUE *argv, VALUE hash)
         key = argv[i];
         rb_hash_delete(result, key);
     }
+    compact_after_delete(result);
 
     return result;
 }
@@ -2692,7 +2770,7 @@ rb_hash_values_at(int argc, VALUE *argv, VALUE hash)
     long i;
 
     for (i=0; i<argc; i++) {
-	rb_ary_push(result, rb_hash_aref(hash, argv[i]));
+        rb_ary_push(result, rb_hash_aref(hash, argv[i]));
     }
     return result;
 }
@@ -2724,7 +2802,7 @@ rb_hash_fetch_values(int argc, VALUE *argv, VALUE hash)
     long i;
 
     for (i=0; i<argc; i++) {
-	rb_ary_push(result, rb_hash_fetch(hash, argv[i]));
+        rb_ary_push(result, rb_hash_fetch(hash, argv[i]));
     }
     return result;
 }
@@ -2733,8 +2811,8 @@ static int
 keep_if_i(VALUE key, VALUE value, VALUE hash)
 {
     if (!RTEST(rb_yield_values(2, key, value))) {
-	rb_hash_modify(hash);
-	return ST_DELETE;
+        rb_hash_modify(hash);
+        return ST_DELETE;
     }
     return ST_CONTINUE;
 }
@@ -2764,7 +2842,8 @@ rb_hash_select(VALUE hash)
     RETURN_SIZED_ENUMERATOR(hash, 0, 0, hash_enum_size);
     result = hash_dup_with_compare_by_id(hash);
     if (!RHASH_EMPTY_P(hash)) {
-	rb_hash_foreach(result, keep_if_i, result);
+        rb_hash_foreach(result, keep_if_i, result);
+        compact_after_delete(result);
     }
     return result;
 }
@@ -2856,6 +2935,7 @@ rb_hash_clear(VALUE hash)
     }
     else {
         st_clear(RHASH_ST_TABLE(hash));
+        compact_after_delete(hash);
     }
 
     return hash;
@@ -2875,7 +2955,7 @@ rb_hash_key_str(VALUE key)
         return rb_fstring(key);
     }
     else {
-	return rb_str_new_frozen(key);
+        return rb_str_new_frozen(key);
     }
 }
 
@@ -2883,7 +2963,7 @@ static int
 hash_aset_str(st_data_t *key, st_data_t *val, struct update_arg *arg, int existing)
 {
     if (!existing && !RB_OBJ_FROZEN(*key)) {
-	*key = rb_hash_key_str(*key);
+        *key = rb_hash_key_str(*key);
     }
     return hash_aset(key, val, arg, existing);
 }
@@ -2925,15 +3005,15 @@ rb_hash_aset(VALUE hash, VALUE key, VALUE val)
     rb_hash_modify(hash);
 
     if (RHASH_TABLE_NULL_P(hash)) {
-	if (iter_lev > 0) no_new_key();
+        if (iter_lev > 0) no_new_key();
         ar_alloc_table(hash);
     }
 
-    if (RHASH_TYPE(hash) == &identhash || rb_obj_class(key) != rb_cString) {
-	RHASH_UPDATE_ITER(hash, iter_lev, key, hash_aset, val);
+    if (!RHASH_STRING_KEY_P(hash, key)) {
+        RHASH_UPDATE_ITER(hash, iter_lev, key, hash_aset, val);
     }
     else {
-	RHASH_UPDATE_ITER(hash, iter_lev, key, hash_aset_str, val);
+        RHASH_UPDATE_ITER(hash, iter_lev, key, hash_aset_str, val);
     }
     return val;
 }
@@ -3143,9 +3223,9 @@ rb_hash_each_pair(VALUE hash)
 {
     RETURN_SIZED_ENUMERATOR(hash, 0, 0, hash_enum_size);
     if (rb_block_pair_yield_optimizable())
-	rb_hash_foreach(hash, each_pair_i_fast, 0);
+        rb_hash_foreach(hash, each_pair_i_fast, 0);
     else
-	rb_hash_foreach(hash, each_pair_i, 0);
+        rb_hash_foreach(hash, each_pair_i, 0);
     return hash;
 }
 
@@ -3161,7 +3241,7 @@ transform_keys_hash_i(VALUE key, VALUE value, VALUE transarg)
     struct transform_keys_args *p = (void *)transarg;
     VALUE trans = p->trans, result = p->result;
     VALUE new_key = rb_hash_lookup2(trans, key, Qundef);
-    if (new_key == Qundef) {
+    if (UNDEF_P(new_key)) {
         if (p->block_given)
             new_key = rb_yield(key);
         else
@@ -3274,7 +3354,7 @@ rb_hash_transform_keys_bang(int argc, VALUE *argv, VALUE hash)
     if (!RHASH_TABLE_EMPTY_P(hash)) {
         long i;
         VALUE new_keys = hash_alloc(0);
-        VALUE pairs = rb_ary_tmp_new(RHASH_SIZE(hash) * 2);
+        VALUE pairs = rb_ary_hidden_new(RHASH_SIZE(hash) * 2);
         rb_hash_foreach(hash, flatten_i, pairs);
         for (i = 0; i < RARRAY_LEN(pairs); i += 2) {
             VALUE key = RARRAY_AREF(pairs, i), new_key, val;
@@ -3282,7 +3362,7 @@ rb_hash_transform_keys_bang(int argc, VALUE *argv, VALUE hash)
             if (!trans) {
                 new_key = rb_yield(key);
             }
-            else if ((new_key = rb_hash_lookup2(trans, key, Qundef)) != Qundef) {
+            else if (!UNDEF_P(new_key = rb_hash_lookup2(trans, key, Qundef))) {
                 /* use the transformed key */
             }
             else if (block_given) {
@@ -3301,6 +3381,7 @@ rb_hash_transform_keys_bang(int argc, VALUE *argv, VALUE hash)
         rb_ary_clear(pairs);
         rb_hash_clear(new_keys);
     }
+    compact_after_delete(hash);
     return hash;
 }
 
@@ -3351,6 +3432,7 @@ rb_hash_transform_values(VALUE hash)
 
     if (!RHASH_EMPTY_P(hash)) {
         rb_hash_stlike_foreach_with_replace(result, transform_values_foreach_func, transform_values_foreach_replace, result);
+        compact_after_delete(result);
     }
 
     return result;
@@ -3419,10 +3501,10 @@ inspect_i(VALUE key, VALUE value, VALUE str)
 
     str2 = rb_inspect(key);
     if (RSTRING_LEN(str) > 1) {
-	rb_str_buf_cat_ascii(str, ", ");
+        rb_str_buf_cat_ascii(str, ", ");
     }
     else {
-	rb_enc_copy(str, str2);
+        rb_enc_copy(str, str2);
     }
     rb_str_buf_append(str, str2);
     rb_str_buf_cat_ascii(str, "=>");
@@ -3460,7 +3542,7 @@ static VALUE
 rb_hash_inspect(VALUE hash)
 {
     if (RHASH_EMPTY_P(hash))
-	return rb_usascii_str_new2("{}");
+        return rb_usascii_str_new2("{}");
     return rb_exec_recursive(inspect_hash, hash, 0);
 }
 
@@ -3535,7 +3617,7 @@ rb_hash_to_h(VALUE hash)
         return rb_hash_to_h_block(hash);
     }
     if (rb_obj_class(hash) != rb_cHash) {
-	const VALUE flags = RBASIC(hash)->flags;
+        const VALUE flags = RBASIC(hash)->flags;
         hash = hash_dup(hash, rb_cHash, flags & RHASH_PROC_DEFAULT);
     }
     return hash;
@@ -3576,10 +3658,10 @@ rb_hash_keys(VALUE hash)
             }
         });
         rb_gc_writebarrier_remember(keys);
-	rb_ary_set_len(keys, size);
+        rb_ary_set_len(keys, size);
     }
     else {
-	rb_hash_foreach(hash, keys_i, keys);
+        rb_hash_foreach(hash, keys_i, keys);
     }
 
     return keys;
@@ -3624,11 +3706,11 @@ rb_hash_values(VALUE hash)
                 size = st_values(table, ptr, size);
             });
         }
-	rb_ary_set_len(values, size);
+        rb_ary_set_len(values, size);
     }
 
     else {
-	rb_hash_foreach(hash, values_i, values);
+        rb_hash_foreach(hash, values_i, values);
     }
 
     return values;
@@ -3658,8 +3740,8 @@ rb_hash_search_value(VALUE key, VALUE value, VALUE arg)
     VALUE *data = (VALUE *)arg;
 
     if (rb_equal(value, data[1])) {
-	data[0] = Qtrue;
-	return ST_STOP;
+        data[0] = Qtrue;
+        return ST_STOP;
     }
     return ST_CONTINUE;
 }
@@ -3730,23 +3812,23 @@ hash_equal(VALUE hash1, VALUE hash2, int eql)
 
     if (hash1 == hash2) return Qtrue;
     if (!RB_TYPE_P(hash2, T_HASH)) {
-	if (!rb_respond_to(hash2, idTo_hash)) {
-	    return Qfalse;
-	}
-	if (eql) {
-	    if (rb_eql(hash2, hash1)) {
-		return Qtrue;
-	    }
-	    else {
-		return Qfalse;
-	    }
-	}
-	else {
-	    return rb_equal(hash2, hash1);
-	}
+        if (!rb_respond_to(hash2, idTo_hash)) {
+            return Qfalse;
+        }
+        if (eql) {
+            if (rb_eql(hash2, hash1)) {
+                return Qtrue;
+            }
+            else {
+                return Qfalse;
+            }
+        }
+        else {
+            return rb_equal(hash2, hash1);
+        }
     }
     if (RHASH_SIZE(hash1) != RHASH_SIZE(hash2))
-	return Qfalse;
+        return Qfalse;
     if (!RHASH_TABLE_EMPTY_P(hash1) && !RHASH_TABLE_EMPTY_P(hash2)) {
         if (RHASH_TYPE(hash1) != RHASH_TYPE(hash2)) {
             return Qfalse;
@@ -3761,7 +3843,7 @@ hash_equal(VALUE hash1, VALUE hash2, int eql)
 #if 0
     if (!(rb_equal(RHASH_IFNONE(hash1), RHASH_IFNONE(hash2)) &&
           FL_TEST(hash1, RHASH_PROC_DEFAULT) == FL_TEST(hash2, RHASH_PROC_DEFAULT)))
-	return Qfalse;
+        return Qfalse;
 #endif
     return Qtrue;
 }
@@ -3849,7 +3931,7 @@ rb_hash_hash(VALUE hash)
     st_index_t hval = rb_hash_start(size);
     hval = rb_hash_uint(hval, (st_index_t)rb_hash_hash);
     if (size) {
-	rb_hash_foreach(hash, hash_i, (VALUE)&hval);
+        rb_hash_foreach(hash, hash_i, (VALUE)&hval);
     }
     hval = rb_hash_end(hval);
     return ST2FIX(hval);
@@ -3887,18 +3969,9 @@ rb_hash_invert(VALUE hash)
 }
 
 static int
-rb_hash_update_callback(st_data_t *key, st_data_t *value, struct update_arg *arg, int existing)
-{
-    *value = arg->arg;
-    return ST_CONTINUE;
-}
-
-NOINSERT_UPDATE_CALLBACK(rb_hash_update_callback)
-
-static int
 rb_hash_update_i(VALUE key, VALUE value, VALUE hash)
 {
-    RHASH_UPDATE(hash, key, rb_hash_update_callback, value);
+    rb_hash_aset(hash, key, value);
     return ST_CONTINUE;
 }
 
@@ -3910,6 +3983,9 @@ rb_hash_update_block_callback(st_data_t *key, st_data_t *value, struct update_ar
     if (existing) {
         newvalue = (st_data_t)rb_yield_values(3, (VALUE)*key, (VALUE)*value, (VALUE)newvalue);
     }
+    else if (RHASH_STRING_KEY_P(arg->hash, *key) && !RB_OBJ_FROZEN(*key)) {
+        *key = rb_hash_key_str(*key);
+    }
     *value = newvalue;
     return ST_CONTINUE;
 }
@@ -4005,7 +4081,7 @@ rb_hash_update_func_callback(st_data_t *key, st_data_t *value, struct update_arg
     VALUE newvalue = uf_arg->value;
 
     if (existing) {
-	newvalue = (*uf_arg->func)((VALUE)*key, (VALUE)*value, newvalue);
+        newvalue = (*uf_arg->func)((VALUE)*key, (VALUE)*value, newvalue);
     }
     *value = newvalue;
     return ST_CONTINUE;
@@ -4030,13 +4106,13 @@ rb_hash_update_by(VALUE hash1, VALUE hash2, rb_hash_update_func *func)
     rb_hash_modify(hash1);
     hash2 = to_hash(hash2);
     if (func) {
-	struct update_func_arg arg;
-	arg.hash = hash1;
-	arg.func = func;
-	rb_hash_foreach(hash2, rb_hash_update_func_i, (VALUE)&arg);
+        struct update_func_arg arg;
+        arg.hash = hash1;
+        arg.func = func;
+        rb_hash_foreach(hash2, rb_hash_update_func_i, (VALUE)&arg);
     }
     else {
-	rb_hash_foreach(hash2, rb_hash_update_i, hash1);
+        rb_hash_foreach(hash2, rb_hash_update_i, hash1);
     }
     return hash1;
 }
@@ -4131,8 +4207,8 @@ assoc_i(VALUE key, VALUE val, VALUE arg)
     VALUE *args = (VALUE *)arg;
 
     if (RTEST(rb_equal(args[0], key))) {
-	args[1] = rb_assoc_new(key, val);
-	return ST_STOP;
+        args[1] = rb_assoc_new(key, val);
+        return ST_STOP;
     }
     return ST_CONTINUE;
 }
@@ -4162,20 +4238,20 @@ rb_hash_assoc(VALUE hash, VALUE key)
     table = RHASH_ST_TABLE(hash);
     orighash = table->type;
 
-    if (orighash != &identhash) {
-	VALUE value;
-	struct reset_hash_type_arg ensure_arg;
-	struct st_hash_type assochash;
+    if (!RHASH_IDENTHASH_P(hash)) {
+        VALUE value;
+        struct reset_hash_type_arg ensure_arg;
+        struct st_hash_type assochash;
 
-	assochash.compare = assoc_cmp;
-	assochash.hash = orighash->hash;
+        assochash.compare = assoc_cmp;
+        assochash.hash = orighash->hash;
         table->type = &assochash;
-	args[0] = hash;
-	args[1] = key;
-	ensure_arg.hash = hash;
-	ensure_arg.orighash = orighash;
-	value = rb_ensure(lookup2_call, (VALUE)&args, reset_hash_type, (VALUE)&ensure_arg);
-	if (value != Qundef) return rb_assoc_new(key, value);
+        args[0] = hash;
+        args[1] = key;
+        ensure_arg.hash = hash;
+        ensure_arg.orighash = orighash;
+        value = rb_ensure(lookup2_call, (VALUE)&args, reset_hash_type, (VALUE)&ensure_arg);
+        if (!UNDEF_P(value)) return rb_assoc_new(key, value);
     }
 
     args[0] = key;
@@ -4190,8 +4266,8 @@ rassoc_i(VALUE key, VALUE val, VALUE arg)
     VALUE *args = (VALUE *)arg;
 
     if (RTEST(rb_equal(args[0], val))) {
-	args[1] = rb_assoc_new(key, val);
-	return ST_STOP;
+        args[1] = rb_assoc_new(key, val);
+        return ST_STOP;
     }
     return ST_CONTINUE;
 }
@@ -4271,26 +4347,26 @@ rb_hash_flatten(int argc, VALUE *argv, VALUE hash)
     rb_check_arity(argc, 0, 1);
 
     if (argc) {
-	int level = NUM2INT(argv[0]);
+        int level = NUM2INT(argv[0]);
 
-	if (level == 0) return rb_hash_to_a(hash);
+        if (level == 0) return rb_hash_to_a(hash);
 
-	ary = rb_ary_new_capa(RHASH_SIZE(hash) * 2);
-	rb_hash_foreach(hash, flatten_i, ary);
-	level--;
+        ary = rb_ary_new_capa(RHASH_SIZE(hash) * 2);
+        rb_hash_foreach(hash, flatten_i, ary);
+        level--;
 
-	if (level > 0) {
-	    VALUE ary_flatten_level = INT2FIX(level);
-	    rb_funcallv(ary, id_flatten_bang, 1, &ary_flatten_level);
-	}
-	else if (level < 0) {
-	    /* flatten recursively */
-	    rb_funcallv(ary, id_flatten_bang, 0, 0);
-	}
+        if (level > 0) {
+            VALUE ary_flatten_level = INT2FIX(level);
+            rb_funcallv(ary, id_flatten_bang, 1, &ary_flatten_level);
+        }
+        else if (level < 0) {
+            /* flatten recursively */
+            rb_funcallv(ary, id_flatten_bang, 0, 0);
+        }
     }
     else {
-	ary = rb_ary_new_capa(RHASH_SIZE(hash) * 2);
-	rb_hash_foreach(hash, flatten_i, ary);
+        ary = rb_ary_new_capa(RHASH_SIZE(hash) * 2);
+        rb_hash_foreach(hash, flatten_i, ary);
     }
 
     return ary;
@@ -4300,7 +4376,7 @@ static int
 delete_if_nil(VALUE key, VALUE value, VALUE hash)
 {
     if (NIL_P(value)) {
-	return ST_DELETE;
+        return ST_DELETE;
     }
     return ST_CONTINUE;
 }
@@ -4309,7 +4385,7 @@ static int
 set_if_not_nil(VALUE key, VALUE value, VALUE hash)
 {
     if (!NIL_P(value)) {
-	rb_hash_aset(hash, key, value);
+        rb_hash_aset(hash, key, value);
     }
     return ST_CONTINUE;
 }
@@ -4329,7 +4405,7 @@ rb_hash_compact(VALUE hash)
 {
     VALUE result = rb_hash_new();
     if (!RHASH_EMPTY_P(hash)) {
-	rb_hash_foreach(hash, set_if_not_nil, result);
+        rb_hash_foreach(hash, set_if_not_nil, result);
     }
     return result;
 }
@@ -4352,9 +4428,9 @@ rb_hash_compact_bang(VALUE hash)
     rb_hash_modify_check(hash);
     n = RHASH_SIZE(hash);
     if (n) {
-	rb_hash_foreach(hash, delete_if_nil, hash);
+        rb_hash_foreach(hash, delete_if_nil, hash);
         if (n != RHASH_SIZE(hash))
-	    return hash;
+            return hash;
     }
     return Qnil;
 }
@@ -4422,7 +4498,7 @@ rb_hash_compare_by_id(VALUE hash)
 MJIT_FUNC_EXPORTED VALUE
 rb_hash_compare_by_id_p(VALUE hash)
 {
-    return RBOOL(RHASH_ST_TABLE_P(hash) && RHASH_ST_TABLE(hash)->type == &identhash);
+    return RBOOL(RHASH_IDENTHASH_P(hash));
 }
 
 VALUE
@@ -4458,8 +4534,8 @@ any_p_i(VALUE key, VALUE value, VALUE arg)
 {
     VALUE ret = rb_yield(rb_assoc_new(key, value));
     if (RTEST(ret)) {
-	*(VALUE *)arg = Qtrue;
-	return ST_STOP;
+        *(VALUE *)arg = Qtrue;
+        return ST_STOP;
     }
     return ST_CONTINUE;
 }
@@ -4469,8 +4545,8 @@ any_p_i_fast(VALUE key, VALUE value, VALUE arg)
 {
     VALUE ret = rb_yield_values(2, key, value);
     if (RTEST(ret)) {
-	*(VALUE *)arg = Qtrue;
-	return ST_STOP;
+        *(VALUE *)arg = Qtrue;
+        return ST_STOP;
     }
     return ST_CONTINUE;
 }
@@ -4480,8 +4556,8 @@ any_p_i_pattern(VALUE key, VALUE value, VALUE arg)
 {
     VALUE ret = rb_funcall(((VALUE *)arg)[1], idEqq, 1, rb_assoc_new(key, value));
     if (RTEST(ret)) {
-	*(VALUE *)arg = Qtrue;
-	return ST_STOP;
+        *(VALUE *)arg = Qtrue;
+        return ST_STOP;
     }
     return ST_CONTINUE;
 }
@@ -4527,19 +4603,19 @@ rb_hash_any_p(int argc, VALUE *argv, VALUE hash)
         if (rb_block_given_p()) {
             rb_warn("given block not used");
         }
-	args[1] = argv[0];
+        args[1] = argv[0];
 
-	rb_hash_foreach(hash, any_p_i_pattern, (VALUE)args);
+        rb_hash_foreach(hash, any_p_i_pattern, (VALUE)args);
     }
     else {
-	if (!rb_block_given_p()) {
-	    /* yields pairs, never false */
-	    return Qtrue;
-	}
+        if (!rb_block_given_p()) {
+            /* yields pairs, never false */
+            return Qtrue;
+        }
         if (rb_block_pair_yield_optimizable())
-	    rb_hash_foreach(hash, any_p_i_fast, (VALUE)args);
-	else
-	    rb_hash_foreach(hash, any_p_i, (VALUE)args);
+            rb_hash_foreach(hash, any_p_i_fast, (VALUE)args);
+        else
+            rb_hash_foreach(hash, any_p_i, (VALUE)args);
     }
     return args[0];
 }
@@ -4588,7 +4664,7 @@ hash_le_i(VALUE key, VALUE value, VALUE arg)
 {
     VALUE *args = (VALUE *)arg;
     VALUE v = rb_hash_lookup2(args[0], key, Qundef);
-    if (v != Qundef && rb_equal(value, v)) return ST_CONTINUE;
+    if (!UNDEF_P(v) && rb_equal(value, v)) return ST_CONTINUE;
     args[1] = Qfalse;
     return ST_STOP;
 }
@@ -4740,7 +4816,7 @@ rb_hash_add_new_element(VALUE hash, VALUE key, VALUE val)
         if (ret != -1) {
             return ret;
         }
-        ar_try_convert_table(hash);
+        ar_force_convert_table(hash, __FILE__, __LINE__);
     }
     tbl = RHASH_TBL_RAW(hash);
     return st_update(tbl, (st_data_t)key, add_new_i, (st_data_t)args);
@@ -4892,12 +4968,12 @@ get_env_cstr(
     char *var;
     rb_encoding *enc = rb_enc_get(str);
     if (!rb_enc_asciicompat(enc)) {
-	rb_raise(rb_eArgError, "bad environment variable %s: ASCII incompatible encoding: %s",
-		 name, rb_enc_name(enc));
+        rb_raise(rb_eArgError, "bad environment variable %s: ASCII incompatible encoding: %s",
+                 name, rb_enc_name(enc));
     }
     var = RSTRING_PTR(str);
     if (memchr(var, '\0', RSTRING_LEN(str))) {
-	rb_raise(rb_eArgError, "bad environment variable %s: contains null byte", name);
+        rb_raise(rb_eArgError, "bad environment variable %s: contains null byte", name);
     }
     return rb_str_fill_terminator(str, 1); /* ASCII compatible */
 }
@@ -4919,7 +4995,7 @@ env_name(volatile VALUE *s)
 static VALUE env_aset(VALUE nm, VALUE val);
 
 static void
-reset_by_modified_env(const char *nam)
+reset_by_modified_env(const char *nam, const char *val)
 {
     /*
      * ENV['TZ'] = nil has a special meaning.
@@ -4928,7 +5004,7 @@ reset_by_modified_env(const char *nam)
      * This hack might works only on Linux glibc.
      */
     if (ENVMATCH(nam, TZ_ENV)) {
-        ruby_reset_timezone();
+        ruby_reset_timezone(val);
     }
 }
 
@@ -4936,7 +5012,7 @@ static VALUE
 env_delete(VALUE name)
 {
     const char *nam = env_name(name);
-    reset_by_modified_env(nam);
+    reset_by_modified_env(nam, NULL);
     VALUE val = getenv_with_lock(nam);
 
     if (!NIL_P(val)) {
@@ -5037,17 +5113,17 @@ env_fetch(int argc, VALUE *argv, VALUE _)
     key = argv[0];
     block_given = rb_block_given_p();
     if (block_given && argc == 2) {
-	rb_warn("block supersedes default value argument");
+        rb_warn("block supersedes default value argument");
     }
     nam = env_name(key);
     env = getenv_with_lock(nam);
 
     if (NIL_P(env)) {
-	if (block_given) return rb_yield(key);
-	if (argc == 1) {
-	    rb_key_err_raise(rb_sprintf("key not found: \"%"PRIsVALUE"\"", key), envtbl, key);
-	}
-	return argv[1];
+        if (block_given) return rb_yield(key);
+        if (argc == 1) {
+            rb_key_err_raise(rb_sprintf("key not found: \"%"PRIsVALUE"\"", key), envtbl, key);
+        }
+        return argv[1];
     }
     return env;
 }
@@ -5059,7 +5135,7 @@ in_origenv(const char *str)
 {
     char **env;
     for (env = origenviron; *env; ++env) {
-	if (*env == str) return 1;
+        if (*env == str) return 1;
     }
     return 0;
 }
@@ -5074,8 +5150,8 @@ envix(const char *nam)
 
     env = GET_ENVIRON(environ);
     for (i = 0; env[i]; i++) {
-	if (ENVNMATCH(env[i],nam,len) && env[i][len] == '=')
-	    break;			/* memcmp must come first to avoid */
+        if (ENVNMATCH(env[i],nam,len) && env[i][len] == '=')
+            break;			/* memcmp must come first to avoid */
     }					/* potential SEGV's */
     FREE_ENVIRON(environ);
     return i;
@@ -5105,16 +5181,16 @@ static int
 check_envsize(size_t n)
 {
     if (_WIN32_WINNT < 0x0600 && rb_w32_osver() < 6) {
-	/* https://msdn.microsoft.com/en-us/library/windows/desktop/ms682653(v=vs.85).aspx */
-	/* Windows Server 2003 and Windows XP: The maximum size of the
-	 * environment block for the process is 32,767 characters. */
-	WCHAR* p = GetEnvironmentStringsW();
-	if (!p) return -1; /* never happen */
-	n += getenvsize(p);
-	FreeEnvironmentStringsW(p);
-	if (n >= getenvblocksize()) {
-	    return -1;
-	}
+        /* https://msdn.microsoft.com/en-us/library/windows/desktop/ms682653(v=vs.85).aspx */
+        /* Windows Server 2003 and Windows XP: The maximum size of the
+         * environment block for the process is 32,767 characters. */
+        WCHAR* p = GetEnvironmentStringsW();
+        if (!p) return -1; /* never happen */
+        n += getenvsize(p);
+        FreeEnvironmentStringsW(p);
+        if (n >= getenvblocksize()) {
+            return -1;
+        }
     }
     return 0;
 }
@@ -5135,7 +5211,7 @@ static const char *
 check_envname(const char *name)
 {
     if (strchr(name, '=')) {
-	invalid_envname(name);
+        invalid_envname(name);
     }
     return name;
 }
@@ -5156,26 +5232,26 @@ ruby_setenv(const char *name, const char *value)
     check_envname(name);
     len = MultiByteToWideChar(CP_UTF8, 0, name, -1, NULL, 0);
     if (value) {
-	int len2;
-	len2 = MultiByteToWideChar(CP_UTF8, 0, value, -1, NULL, 0);
-	if (check_envsize((size_t)len + len2)) { /* len and len2 include '\0' */
-	    goto fail;  /* 2 for '=' & '\0' */
-	}
-	wname = ALLOCV_N(WCHAR, buf, len + len2);
-	wvalue = wname + len;
-	MultiByteToWideChar(CP_UTF8, 0, name, -1, wname, len);
-	MultiByteToWideChar(CP_UTF8, 0, value, -1, wvalue, len2);
+        int len2;
+        len2 = MultiByteToWideChar(CP_UTF8, 0, value, -1, NULL, 0);
+        if (check_envsize((size_t)len + len2)) { /* len and len2 include '\0' */
+            goto fail;  /* 2 for '=' & '\0' */
+        }
+        wname = ALLOCV_N(WCHAR, buf, len + len2);
+        wvalue = wname + len;
+        MultiByteToWideChar(CP_UTF8, 0, name, -1, wname, len);
+        MultiByteToWideChar(CP_UTF8, 0, value, -1, wvalue, len2);
 #ifndef HAVE__WPUTENV_S
-	wname[len-1] = L'=';
+        wname[len-1] = L'=';
 #endif
     }
     else {
-	wname = ALLOCV_N(WCHAR, buf, len + 1);
-	MultiByteToWideChar(CP_UTF8, 0, name, -1, wname, len);
-	wvalue = wname + len;
-	*wvalue = L'\0';
+        wname = ALLOCV_N(WCHAR, buf, len + 1);
+        MultiByteToWideChar(CP_UTF8, 0, name, -1, wname, len);
+        wvalue = wname + len;
+        *wvalue = L'\0';
 #ifndef HAVE__WPUTENV_S
-	wname[len-1] = L'=';
+        wname[len-1] = L'=';
 #endif
     }
 
@@ -5193,13 +5269,13 @@ ruby_setenv(const char *name, const char *value)
     /* even if putenv() failed, clean up and try to delete the
      * variable from the system area. */
     if (!value || !*value) {
-	/* putenv() doesn't handle empty value */
-	if (!SetEnvironmentVariable(name, value) &&
-	    GetLastError() != ERROR_ENVVAR_NOT_FOUND) goto fail;
+        /* putenv() doesn't handle empty value */
+        if (!SetEnvironmentVariable(name, value) &&
+            GetLastError() != ERROR_ENVVAR_NOT_FOUND) goto fail;
     }
     if (failed) {
       fail:
-	invalid_envname(name);
+        invalid_envname(name);
     }
 #elif defined(HAVE_SETENV) && defined(HAVE_UNSETENV)
     if (value) {
@@ -5269,7 +5345,7 @@ ruby_setenv(const char *name, const char *value)
         ENV_UNLOCK();
 
         if (ret) {
-	    free(mem_ptr);
+            free(mem_ptr);
             rb_sys_fail_str(rb_sprintf("putenv(%s)", name));
         }
     }
@@ -5386,7 +5462,7 @@ env_aset(VALUE nm, VALUE val)
 
     if (NIL_P(val)) {
         env_delete(nm);
-	return Qnil;
+        return Qnil;
     }
     SafeStringValue(nm);
     SafeStringValue(val);
@@ -5396,7 +5472,7 @@ env_aset(VALUE nm, VALUE val)
     get_env_ptr(value, val);
 
     ruby_setenv(name, value);
-    reset_by_modified_env(name);
+    reset_by_modified_env(name, value);
     return val;
 }
 
@@ -5492,7 +5568,7 @@ env_each_key(VALUE ehash)
     RETURN_SIZED_ENUMERATOR(ehash, 0, 0, rb_env_size);
     keys = env_keys(FALSE);
     for (i=0; i<RARRAY_LEN(keys); i++) {
-	rb_yield(RARRAY_AREF(keys, i));
+        rb_yield(RARRAY_AREF(keys, i));
     }
     return ehash;
 }
@@ -5564,7 +5640,7 @@ env_each_value(VALUE ehash)
     RETURN_SIZED_ENUMERATOR(ehash, 0, 0, rb_env_size);
     values = env_values();
     for (i=0; i<RARRAY_LEN(values); i++) {
-	rb_yield(RARRAY_AREF(values, i));
+        rb_yield(RARRAY_AREF(values, i));
     }
     return ehash;
 }
@@ -5614,13 +5690,13 @@ env_each_pair(VALUE ehash)
 
     if (rb_block_pair_yield_optimizable()) {
         for (i=0; i<RARRAY_LEN(ary); i+=2) {
-	    rb_yield_values(2, RARRAY_AREF(ary, i), RARRAY_AREF(ary, i+1));
-	}
+            rb_yield_values(2, RARRAY_AREF(ary, i), RARRAY_AREF(ary, i+1));
+        }
     }
     else {
-	for (i=0; i<RARRAY_LEN(ary); i+=2) {
-	    rb_yield(rb_assoc_new(RARRAY_AREF(ary, i), RARRAY_AREF(ary, i+1)));
-	}
+        for (i=0; i<RARRAY_LEN(ary); i+=2) {
+            rb_yield(rb_assoc_new(RARRAY_AREF(ary, i), RARRAY_AREF(ary, i+1)));
+        }
     }
 
     return ehash;
@@ -5659,13 +5735,13 @@ env_reject_bang(VALUE ehash)
     keys = env_keys(FALSE);
     RBASIC_CLEAR_CLASS(keys);
     for (i=0; i<RARRAY_LEN(keys); i++) {
-	VALUE val = rb_f_getenv(Qnil, RARRAY_AREF(keys, i));
-	if (!NIL_P(val)) {
-	    if (RTEST(rb_yield_values(2, RARRAY_AREF(keys, i), val))) {
+        VALUE val = rb_f_getenv(Qnil, RARRAY_AREF(keys, i));
+        if (!NIL_P(val)) {
+            if (RTEST(rb_yield_values(2, RARRAY_AREF(keys, i), val))) {
                 env_delete(RARRAY_AREF(keys, i));
-		del++;
-	    }
-	}
+                del++;
+            }
+        }
     }
     RB_GC_GUARD(keys);
     if (del == 0) return Qnil;
@@ -5725,7 +5801,7 @@ env_values_at(int argc, VALUE *argv, VALUE _)
 
     result = rb_ary_new();
     for (i=0; i<argc; i++) {
-	rb_ary_push(result, rb_f_getenv(Qnil, argv[i]));
+        rb_ary_push(result, rb_f_getenv(Qnil, argv[i]));
     }
     return result;
 }
@@ -5762,13 +5838,13 @@ env_select(VALUE ehash)
     result = rb_hash_new();
     keys = env_keys(FALSE);
     for (i = 0; i < RARRAY_LEN(keys); ++i) {
-	VALUE key = RARRAY_AREF(keys, i);
-	VALUE val = rb_f_getenv(Qnil, key);
-	if (!NIL_P(val)) {
-	    if (RTEST(rb_yield_values(2, key, val))) {
-		rb_hash_aset(result, key, val);
-	    }
-	}
+        VALUE key = RARRAY_AREF(keys, i);
+        VALUE val = rb_f_getenv(Qnil, key);
+        if (!NIL_P(val)) {
+            if (RTEST(rb_yield_values(2, key, val))) {
+                rb_hash_aset(result, key, val);
+            }
+        }
     }
     RB_GC_GUARD(keys);
 
@@ -5823,13 +5899,13 @@ env_select_bang(VALUE ehash)
     keys = env_keys(FALSE);
     RBASIC_CLEAR_CLASS(keys);
     for (i=0; i<RARRAY_LEN(keys); i++) {
-	VALUE val = rb_f_getenv(Qnil, RARRAY_AREF(keys, i));
-	if (!NIL_P(val)) {
-	    if (!RTEST(rb_yield_values(2, RARRAY_AREF(keys, i), val))) {
+        VALUE val = rb_f_getenv(Qnil, RARRAY_AREF(keys, i));
+        if (!NIL_P(val)) {
+            if (!RTEST(rb_yield_values(2, RARRAY_AREF(keys, i), val))) {
                 env_delete(RARRAY_AREF(keys, i));
-		del++;
-	    }
-	}
+                del++;
+            }
+        }
     }
     RB_GC_GUARD(keys);
     if (del == 0) return Qnil;
@@ -5951,24 +6027,23 @@ env_to_s(VALUE _)
 static VALUE
 env_inspect(VALUE _)
 {
-    VALUE i;
     VALUE str = rb_str_buf_new2("{");
+    rb_encoding *enc = env_encoding();
 
     ENV_LOCK();
     {
         char **env = GET_ENVIRON(environ);
         while (*env) {
-            char *s = strchr(*env, '=');
+            const char *s = strchr(*env, '=');
 
             if (env != environ) {
                 rb_str_buf_cat2(str, ", ");
             }
             if (s) {
-                rb_str_buf_cat2(str, "\"");
-                rb_str_buf_cat(str, *env, s-*env);
-                rb_str_buf_cat2(str, "\"=>");
-                i = rb_inspect(rb_str_new2(s+1));
-                rb_str_buf_append(str, i);
+                rb_str_buf_append(str, rb_str_inspect(env_enc_str_new(*env, s-*env, enc)));
+                rb_str_buf_cat2(str, "=>");
+                s++;
+                rb_str_buf_append(str, rb_str_inspect(env_enc_str_new(s, strlen(s), enc)));
             }
             env++;
         }
@@ -6080,7 +6155,7 @@ env_empty_p(VALUE _)
         if (env[0] != 0) {
             empty = false;
         }
-	FREE_ENVIRON(environ);
+        FREE_ENVIRON(environ);
     }
     ENV_UNLOCK();
 
@@ -6297,7 +6372,7 @@ env_to_hash(void)
                              env_str_new2(s+1));
             }
             env++;
-	}
+        }
         FREE_ENVIRON(environ);
     }
     ENV_UNLOCK();
@@ -6561,7 +6636,7 @@ env_update_block_i(VALUE key, VALUE val, VALUE _)
 {
     VALUE oldval = rb_f_getenv(Qnil, key);
     if (!NIL_P(oldval)) {
-	val = rb_yield_values(3, key, oldval, val);
+        val = rb_yield_values(3, key, oldval, val);
     }
     env_aset(key, val);
     return ST_CONTINUE;
@@ -6569,10 +6644,12 @@ env_update_block_i(VALUE key, VALUE val, VALUE _)
 
 /*
  * call-seq:
- *   ENV.update(hash)                                     -> ENV
- *   ENV.update(hash) { |name, env_val, hash_val| block } -> ENV
- *   ENV.merge!(hash)                                     -> ENV
- *   ENV.merge!(hash) { |name, env_val, hash_val| block } -> ENV
+ *   ENV.update                                              -> ENV
+ *   ENV.update(*hashes)                                     -> ENV
+ *   ENV.update(*hashes) { |name, env_val, hash_val| block } -> ENV
+ *   ENV.merge!                                              -> ENV
+ *   ENV.merge!(*hashes)                                     -> ENV
+ *   ENV.merge!(*hashes) { |name, env_val, hash_val| block } -> ENV
  *
  * ENV.update is an alias for ENV.merge!.
  *
@@ -6604,41 +6681,39 @@ env_update_block_i(VALUE key, VALUE val, VALUE _)
  * those following are ignored.
  */
 static VALUE
-env_update(VALUE env, VALUE hash)
+env_update(int argc, VALUE *argv, VALUE env)
 {
-    if (env == hash) return env;
-    hash = to_hash(hash);
     rb_foreach_func *func = rb_block_given_p() ?
         env_update_block_i : env_update_i;
-    rb_hash_foreach(hash, func, 0);
+    for (int i = 0; i < argc; ++i) {
+        VALUE hash = argv[i];
+        if (env == hash) continue;
+        hash = to_hash(hash);
+        rb_hash_foreach(hash, func, 0);
+    }
     return env;
 }
 
+NORETURN(static VALUE env_clone(int, VALUE *, VALUE));
 /*
  * call-seq:
- *   ENV.clone(freeze: nil) -> ENV
+ *   ENV.clone(freeze: nil) # raises TypeError
  *
- * Returns ENV itself, and warns because ENV is a wrapper for the
- * process-wide environment variables and a clone is useless.
- * If +freeze+ keyword is given and not +nil+ or +false+, raises ArgumentError.
- * If +freeze+ keyword is given and +true+, raises TypeError, as ENV storage
- * cannot be frozen.
+ * Raises TypeError, because ENV is a wrapper for the process-wide
+ * environment variables and a clone is useless.
+ * Use #to_h to get a copy of ENV data as a hash.
  */
 static VALUE
 env_clone(int argc, VALUE *argv, VALUE obj)
 {
     if (argc) {
-        VALUE opt, kwfreeze;
+        VALUE opt;
         if (rb_scan_args(argc, argv, "0:", &opt) < argc) {
-            kwfreeze = rb_get_freeze_opt(1, &opt);
-            if (RTEST(kwfreeze)) {
-                rb_raise(rb_eTypeError, "cannot freeze ENV");
-            }
+            rb_get_freeze_opt(1, &opt);
         }
     }
 
-    rb_warn_deprecated("ENV.clone", "ENV.to_h");
-    return envtbl;
+    rb_raise(rb_eTypeError, "Cannot clone ENV, use ENV.to_h to get a copy of ENV as a hash");
 }
 
 NORETURN(static VALUE env_dup(VALUE));
@@ -7144,7 +7219,6 @@ void
 Init_Hash(void)
 {
     id_hash = rb_intern_const("hash");
-    id_default = rb_intern_const("default");
     id_flatten_bang = rb_intern_const("flatten!");
     id_hash_iter_lev = rb_make_internal_id();
 
@@ -7438,8 +7512,8 @@ Init_Hash(void)
     rb_define_singleton_method(envtbl, "freeze", env_freeze, 0);
     rb_define_singleton_method(envtbl, "invert", env_invert, 0);
     rb_define_singleton_method(envtbl, "replace", env_replace, 1);
-    rb_define_singleton_method(envtbl, "update", env_update, 1);
-    rb_define_singleton_method(envtbl, "merge!", env_update, 1);
+    rb_define_singleton_method(envtbl, "update", env_update, -1);
+    rb_define_singleton_method(envtbl, "merge!", env_update, -1);
     rb_define_singleton_method(envtbl, "inspect", env_inspect, 0);
     rb_define_singleton_method(envtbl, "rehash", env_none, 0);
     rb_define_singleton_method(envtbl, "to_a", env_to_a, 0);
diff --git a/hrtime.h b/hrtime.h
index 4ac3d54723..7ed4e6b04c 100644
--- a/hrtime.h
+++ b/hrtime.h
@@ -36,6 +36,7 @@
 #define RB_HRTIME_PER_MSEC (RB_HRTIME_PER_USEC * (rb_hrtime_t)1000)
 #define RB_HRTIME_PER_SEC  (RB_HRTIME_PER_MSEC * (rb_hrtime_t)1000)
 #define RB_HRTIME_MAX      UINT64_MAX
+#define RB_HRTIME_MIN      ((rb_hrtime_t)0)
 
 /*
  * Lets try to support time travelers.  Lets assume anybody with a time machine
@@ -91,6 +92,15 @@ rb_hrtime_add(rb_hrtime_t a, rb_hrtime_t b)
     return c;
 }
 
+static inline rb_hrtime_t
+rb_hrtime_sub(rb_hrtime_t a, rb_hrtime_t b)
+{
+    if (a < b) {
+        return RB_HRTIME_MIN;
+    }
+    return a - b;
+}
+
 /*
  * convert a timeval struct to rb_hrtime_t, clamping at RB_HRTIME_MAX
  */
@@ -196,6 +206,7 @@ double2hrtime(rb_hrtime_t *hrt, double d)
     const double TIMESPEC_SEC_MAX_PLUS_ONE = 2.0 * (TIMESPEC_SEC_MAX_as_double / 2.0 + 1.0);
 
     if (TIMESPEC_SEC_MAX_PLUS_ONE <= d) {
+        *hrt = RB_HRTIME_MAX;
         return NULL;
     }
     else if (d <= 0) {
diff --git a/id_table.c b/id_table.c
index a1b09ba0ed..a9a041b955 100644
--- a/id_table.c
+++ b/id_table.c
@@ -85,9 +85,9 @@ rb_id_table_init(struct rb_id_table *tbl, int capa)
 {
     MEMZERO(tbl, struct rb_id_table, 1);
     if (capa > 0) {
-	capa = round_capa(capa);
-	tbl->capa = (int)capa;
-	tbl->items = ZALLOC_N(item_t, capa);
+        capa = round_capa(capa);
+        tbl->capa = (int)capa;
+        tbl->items = ZALLOC_N(item_t, capa);
     }
     return tbl;
 }
@@ -130,16 +130,16 @@ static int
 hash_table_index(struct rb_id_table* tbl, id_key_t key)
 {
     if (tbl->capa > 0) {
-	int mask = tbl->capa - 1;
-	int ix = key & mask;
-	int d = 1;
-	while (key != ITEM_GET_KEY(tbl, ix)) {
-	    if (!ITEM_COLLIDED(tbl, ix))
-		return -1;
-	    ix = (ix + d) & mask;
-	    d++;
-	}
-	return ix;
+        int mask = tbl->capa - 1;
+        int ix = key & mask;
+        int d = 1;
+        while (key != ITEM_GET_KEY(tbl, ix)) {
+            if (!ITEM_COLLIDED(tbl, ix))
+                return -1;
+            ix = (ix + d) & mask;
+            d++;
+        }
+        return ix;
     }
     return -1;
 }
@@ -152,13 +152,13 @@ hash_table_raw_insert(struct rb_id_table *tbl, id_key_t key, VALUE val)
     int d = 1;
     assert(key != 0);
     while (ITEM_KEY_ISSET(tbl, ix)) {
-	ITEM_SET_COLLIDED(tbl, ix);
-	ix = (ix + d) & mask;
-	d++;
+        ITEM_SET_COLLIDED(tbl, ix);
+        ix = (ix + d) & mask;
+        d++;
     }
     tbl->num++;
     if (!ITEM_COLLIDED(tbl, ix)) {
-	tbl->used++;
+        tbl->used++;
     }
     ITEM_SET_KEY(tbl, ix, key);
     tbl->items[ix].val = val;
@@ -168,16 +168,16 @@ static int
 hash_delete_index(struct rb_id_table *tbl, int ix)
 {
     if (ix >= 0) {
-	if (!ITEM_COLLIDED(tbl, ix)) {
-	    tbl->used--;
-	}
-	tbl->num--;
-	ITEM_SET_KEY(tbl, ix, 0);
-	tbl->items[ix].val = 0;
-	return TRUE;
+        if (!ITEM_COLLIDED(tbl, ix)) {
+            tbl->used--;
+        }
+        tbl->num--;
+        ITEM_SET_KEY(tbl, ix, 0);
+        tbl->items[ix].val = 0;
+        return TRUE;
     }
     else {
-	return FALSE;
+        return FALSE;
     }
 }
 
@@ -185,24 +185,24 @@ static void
 hash_table_extend(struct rb_id_table* tbl)
 {
     if (tbl->used + (tbl->used >> 1) >= tbl->capa) {
-	int new_cap = round_capa(tbl->num + (tbl->num >> 1));
-	int i;
-	item_t* old;
-	struct rb_id_table tmp_tbl = {0, 0, 0};
-	if (new_cap < tbl->capa) {
-	    new_cap = round_capa(tbl->used + (tbl->used >> 1));
-	}
-	tmp_tbl.capa = new_cap;
-	tmp_tbl.items = ZALLOC_N(item_t, new_cap);
-	for (i = 0; i < tbl->capa; i++) {
-	    id_key_t key = ITEM_GET_KEY(tbl, i);
-	    if (key != 0) {
-		hash_table_raw_insert(&tmp_tbl, key, tbl->items[i].val);
-	    }
-	}
-	old = tbl->items;
-	*tbl = tmp_tbl;
-	xfree(old);
+        int new_cap = round_capa(tbl->num + (tbl->num >> 1));
+        int i;
+        item_t* old;
+        struct rb_id_table tmp_tbl = {0, 0, 0};
+        if (new_cap < tbl->capa) {
+            new_cap = round_capa(tbl->used + (tbl->used >> 1));
+        }
+        tmp_tbl.capa = new_cap;
+        tmp_tbl.items = ZALLOC_N(item_t, new_cap);
+        for (i = 0; i < tbl->capa; i++) {
+            id_key_t key = ITEM_GET_KEY(tbl, i);
+            if (key != 0) {
+                hash_table_raw_insert(&tmp_tbl, key, tbl->items[i].val);
+            }
+        }
+        old = tbl->items;
+        *tbl = tmp_tbl;
+        xfree(old);
     }
 }
 
@@ -216,9 +216,9 @@ hash_table_show(struct rb_id_table *tbl)
 
     fprintf(stderr, "tbl: %p (capa: %d, num: %d, used: %d)\n", tbl, tbl->capa, tbl->num, tbl->used);
     for (i=0; i<capa; i++) {
-	if (ITEM_KEY_ISSET(tbl, i)) {
-	    fprintf(stderr, " -> [%d] %s %d\n", i, rb_id2name(key2id(keys[i])), (int)keys[i]);
-	}
+        if (ITEM_KEY_ISSET(tbl, i)) {
+            fprintf(stderr, " -> [%d] %s %d\n", i, rb_id2name(key2id(keys[i])), (int)keys[i]);
+        }
     }
 }
 #endif
@@ -231,10 +231,10 @@ rb_id_table_lookup(struct rb_id_table *tbl, ID id, VALUE *valp)
 
     if (index >= 0) {
         *valp = tbl->items[index].val;
-	return TRUE;
+        return TRUE;
     }
     else {
-	return FALSE;
+        return FALSE;
     }
 }
 
@@ -244,11 +244,11 @@ rb_id_table_insert_key(struct rb_id_table *tbl, const id_key_t key, const VALUE
     const int index = hash_table_index(tbl, key);
 
     if (index >= 0) {
-	tbl->items[index].val = val;
+        tbl->items[index].val = val;
     }
     else {
-	hash_table_extend(tbl);
-	hash_table_raw_insert(tbl, key, val);
+        hash_table_extend(tbl);
+        hash_table_raw_insert(tbl, key, val);
     }
     return TRUE;
 }
@@ -273,16 +273,16 @@ rb_id_table_foreach(struct rb_id_table *tbl, rb_id_table_foreach_func_t *func, v
     int i, capa = tbl->capa;
 
     for (i=0; i<capa; i++) {
-	if (ITEM_KEY_ISSET(tbl, i)) {
-	    const id_key_t key = ITEM_GET_KEY(tbl, i);
-	    enum rb_id_table_iterator_result ret = (*func)(key2id(key), tbl->items[i].val, data);
-	    assert(key != 0);
-
-	    if (ret == ID_TABLE_DELETE)
-		hash_delete_index(tbl, i);
-	    else if (ret == ID_TABLE_STOP)
-		return;
-	}
+        if (ITEM_KEY_ISSET(tbl, i)) {
+            const id_key_t key = ITEM_GET_KEY(tbl, i);
+            enum rb_id_table_iterator_result ret = (*func)(key2id(key), tbl->items[i].val, data);
+            assert(key != 0);
+
+            if (ret == ID_TABLE_DELETE)
+                hash_delete_index(tbl, i);
+            else if (ret == ID_TABLE_STOP)
+                return;
+        }
     }
 }
 
@@ -292,14 +292,14 @@ rb_id_table_foreach_values(struct rb_id_table *tbl, rb_id_table_foreach_values_f
     int i, capa = tbl->capa;
 
     for (i=0; i<capa; i++) {
-	if (ITEM_KEY_ISSET(tbl, i)) {
-	    enum rb_id_table_iterator_result ret = (*func)(tbl->items[i].val, data);
-
-	    if (ret == ID_TABLE_DELETE)
-		hash_delete_index(tbl, i);
-	    else if (ret == ID_TABLE_STOP)
-		return;
-	}
+        if (ITEM_KEY_ISSET(tbl, i)) {
+            enum rb_id_table_iterator_result ret = (*func)(tbl->items[i].val, data);
+
+            if (ret == ID_TABLE_DELETE)
+                hash_delete_index(tbl, i);
+            else if (ret == ID_TABLE_STOP)
+                return;
+        }
     }
 }
 
diff --git a/id_table.h b/id_table.h
index 9d9eb5648e..f72e2d1d92 100644
--- a/id_table.h
+++ b/id_table.h
@@ -19,7 +19,6 @@ struct rb_id_table *rb_id_table_create(size_t size);
 void rb_id_table_free(struct rb_id_table *tbl);
 void rb_id_table_clear(struct rb_id_table *tbl);
 
-size_t rb_id_table_size(const struct rb_id_table *tbl);
 size_t rb_id_table_memsize(const struct rb_id_table *tbl);
 
 int rb_id_table_insert(struct rb_id_table *tbl, ID id, VALUE val);
@@ -33,4 +32,8 @@ void rb_id_table_foreach(struct rb_id_table *tbl, rb_id_table_foreach_func_t *fu
 void rb_id_table_foreach_values(struct rb_id_table *tbl, rb_id_table_foreach_values_func_t *func, void *data);
 void rb_id_table_foreach_values_with_replace(struct rb_id_table *tbl, rb_id_table_foreach_values_func_t *func, rb_id_table_update_value_callback_func_t *replace, void *data);
 
+RUBY_SYMBOL_EXPORT_BEGIN
+size_t rb_id_table_size(const struct rb_id_table *tbl);
+RUBY_SYMBOL_EXPORT_END
+
 #endif	/* RUBY_ID_TABLE_H */
diff --git a/include/ruby/assert.h b/include/ruby/assert.h
index c9f2c3fbef..0c052363bc 100644
--- a/include/ruby/assert.h
+++ b/include/ruby/assert.h
@@ -103,7 +103,7 @@
 # /* keep NDEBUG undefined */
 
 #elif (RBIMPL_NDEBUG == 0) && (RBIMPL_RUBY_DEBUG == 0)
-# /* The (*1) situation in avobe diagram. */
+# /* The (*1) situation in above diagram. */
 # define RUBY_DEBUG 0
 # define RUBY_NDEBUG 1
 # define NDEBUG
diff --git a/include/ruby/debug.h b/include/ruby/debug.h
index c88da9c43d..f95acdb17e 100644
--- a/include/ruby/debug.h
+++ b/include/ruby/debug.h
@@ -207,6 +207,17 @@ typedef VALUE (*rb_debug_inspector_func_t)(const rb_debug_inspector_t *dc, void
 VALUE rb_debug_inspector_open(rb_debug_inspector_func_t func, void *data);
 
 /**
+ * Queries  the backtrace  object  of the  context.   This is  as  if you  call
+ * `caller_locations` at the point of debugger.
+ *
+ * @param[in]  dc  A debug context.
+ * @return     An array  of `Thread::Backtrace::Location` which  represents the
+ *             current point of execution at `dc`.
+
+ */
+VALUE rb_debug_inspector_backtrace_locations(const rb_debug_inspector_t *dc);
+
+/**
  * Queries the current receiver of the passed context's upper frame.
  *
  * @param[in]  dc           A debug context.
@@ -250,15 +261,27 @@ VALUE rb_debug_inspector_frame_binding_get(const rb_debug_inspector_t *dc, long
 VALUE rb_debug_inspector_frame_iseq_get(const rb_debug_inspector_t *dc, long index);
 
 /**
- * Queries  the backtrace  object  of the  context.   This is  as  if you  call
- * `caller_locations` at the point of debugger.
+ * Queries the depth of the passed context's upper frame.
  *
- * @param[in]  dc  A debug context.
- * @return     An array  of `Thread::Backtrace::Location` which  represents the
- *             current point of execution at `dc`.
+ * Note that the depth is not same as the frame index because debug_inspector
+ * skips some special frames but the depth counts all frames.
+ *
+ * @param[in]  dc           A debug context.
+ * @param[in]  index        Index of the frame from top to bottom.
+ * @exception  rb_eArgError `index` out of range.
+ * @retval     The depth at `index`-th frame in Integer.
+ */
+VALUE rb_debug_inspector_frame_depth(const rb_debug_inspector_t *dc, long index);
+
+// A macro to recognize `rb_debug_inspector_frame_depth()` is available or not
+#define RB_DEBUG_INSPECTOR_FRAME_DEPTH(dc, index) rb_debug_inspector_frame_depth(dc, index)
 
+/**
+ * Return current frmae depth.
+ *
+ * @retval     The depth of the current frame in Integer.
  */
-VALUE rb_debug_inspector_backtrace_locations(const rb_debug_inspector_t *dc);
+VALUE rb_debug_inspector_current_depth(void);
 
 /** @} */
 
diff --git a/include/ruby/fiber/scheduler.h b/include/ruby/fiber/scheduler.h
index 3ea52beb95..250b39b6df 100644
--- a/include/ruby/fiber/scheduler.h
+++ b/include/ruby/fiber/scheduler.h
@@ -23,6 +23,8 @@
 
 RBIMPL_SYMBOL_EXPORT_BEGIN()
 
+#define RUBY_FIBER_SCHEDULER_VERSION 2
+
 struct timeval;
 
 /**
@@ -43,10 +45,12 @@ struct timeval;
  * @return              A `VALUE` which contains the result and/or errno.
  */
 static inline VALUE
-rb_fiber_scheduler_io_result(ssize_t result, int error) {
+rb_fiber_scheduler_io_result(ssize_t result, int error)
+{
     if (result == -1) {
         return RB_INT2NUM(-error);
-    } else {
+    }
+    else {
         return RB_SIZE2NUM(result);
     }
 }
@@ -63,11 +67,13 @@ rb_fiber_scheduler_io_result(ssize_t result, int error) {
  * @return              The original result of the system call.
  */
 static inline ssize_t
-rb_fiber_scheduler_io_result_apply(VALUE result) {
+rb_fiber_scheduler_io_result_apply(VALUE result)
+{
     if (RB_FIXNUM_P(result) && RB_NUM2INT(result) < 0) {
         errno = -RB_NUM2INT(result);
         return -1;
-    } else {
+    }
+    else {
         return RB_NUM2SIZE(result);
     }
 }
@@ -140,7 +146,7 @@ VALUE rb_fiber_scheduler_make_timeout(struct timeval *timeout);
 VALUE rb_fiber_scheduler_close(VALUE scheduler);
 
 /**
- * Nonblocking  `sleep`.   Depending  on  scheduler  implementation,  this  for
+ * Non-blocking  `sleep`.  Depending  on  scheduler  implementation,  this  for
  * instance switches to another fiber etc.
  *
  * @param[in]  scheduler  Target scheduler.
@@ -168,7 +174,7 @@ int rb_fiber_scheduler_supports_process_wait(VALUE scheduler);
 #endif
 
 /**
- * Nonblocking  `waitpid`.  Depending  on  scheduler  implementation, this  for
+ * Non-blocking `waitpid`.  Depending  on  scheduler  implementation, this  for
  * instance switches to another fiber etc.
  *
  * @param[in]  scheduler  Target scheduler.
@@ -179,7 +185,7 @@ int rb_fiber_scheduler_supports_process_wait(VALUE scheduler);
 VALUE rb_fiber_scheduler_process_wait(VALUE scheduler, rb_pid_t pid, int flags);
 
 /**
- * Nonblocking  wait   for  the  passed   "blocker",  which  is   for  instance
+ * Non-blocking  wait  for  the  passed   "blocker",  which  is   for  instance
  * `Thread.join` or `Mutex.lock`.  Depending  on scheduler implementation, this
  * for instance switches to another fiber etc.
  *
@@ -201,8 +207,8 @@ VALUE rb_fiber_scheduler_block(VALUE scheduler, VALUE blocker, VALUE timeout);
 VALUE rb_fiber_scheduler_unblock(VALUE scheduler, VALUE blocker, VALUE fiber);
 
 /**
- * Nonblocking version of rb_io_wait().  Depending on scheduler implementation,
- * this for instance switches to another fiber etc.
+ * Non-blocking version of rb_io_wait().  Depending on scheduler
+ * implementation, this for instance switches to another fiber etc.
  *
  * The  "events" here  is a  Ruby level  integer, which  is an  OR-ed value  of
  * `IO::READABLE`, `IO::WRITABLE`, and `IO::PRIORITY`.
@@ -216,7 +222,7 @@ VALUE rb_fiber_scheduler_unblock(VALUE scheduler, VALUE blocker, VALUE fiber);
 VALUE rb_fiber_scheduler_io_wait(VALUE scheduler, VALUE io, VALUE events, VALUE timeout);
 
 /**
- * Nonblocking  wait until  the passed  IO  is ready  for reading.   This is  a
+ * Non-blocking  wait until the passed  IO  is ready  for reading.   This is  a
  * special  case   of  rb_fiber_scheduler_io_wait(),  where  the   interest  is
  * `IO::READABLE` and timeout is never.
  *
@@ -227,7 +233,7 @@ VALUE rb_fiber_scheduler_io_wait(VALUE scheduler, VALUE io, VALUE events, VALUE
 VALUE rb_fiber_scheduler_io_wait_readable(VALUE scheduler, VALUE io);
 
 /**
- * Nonblocking  wait until  the passed  IO  is ready  for writing.   This is  a
+ * Non-blocking  wait until  the passed  IO  is ready  for writing.   This is a
  * special  case   of  rb_fiber_scheduler_io_wait(),  where  the   interest  is
  * `IO::WRITABLE` and timeout is never.
  *
@@ -238,61 +244,86 @@ VALUE rb_fiber_scheduler_io_wait_readable(VALUE scheduler, VALUE io);
 VALUE rb_fiber_scheduler_io_wait_writable(VALUE scheduler, VALUE io);
 
 /**
- * Nonblocking read from the passed IO.
+ * Non-blocking version of `IO.select`.
+ *
+ * It's possible that this will be emulated using a thread, so you should not
+ * rely on it for high performance.
+ *
+ * @param[in]  scheduler    Target scheduler.
+ * @param[in]  readables    An array of readable objects.
+ * @param[in]  writables    An array of writable objects.
+ * @param[in]  exceptables  An array of objects that might encounter exceptional conditions.
+ * @param[in]  timeout      Numeric timeout or nil.
+ * @return     What `scheduler.io_select` returns, normally a 3-tuple of arrays of ready objects.
+ */
+VALUE rb_fiber_scheduler_io_select(VALUE scheduler, VALUE readables, VALUE writables, VALUE exceptables, VALUE timeout);
+
+/**
+ * Non-blocking version of `IO.select`, `argv` variant.
+ */
+VALUE rb_fiber_scheduler_io_selectv(VALUE scheduler, int argc, VALUE *argv);
+
+/**
+ * Non-blocking read from the passed IO.
  *
  * @param[in]   scheduler    Target scheduler.
  * @param[out]  io           An io object to read from.
  * @param[out]  buffer       Return buffer.
  * @param[in]   length       Requested number of bytes to read.
+ * @param[in]   offset       The offset in the buffer to read to.
  * @retval      RUBY_Qundef  `scheduler` doesn't have `#io_read`.
  * @return      otherwise    What `scheduler.io_read` returns `[-errno, size]`.
  */
-VALUE rb_fiber_scheduler_io_read(VALUE scheduler, VALUE io, VALUE buffer, size_t length);
+VALUE rb_fiber_scheduler_io_read(VALUE scheduler, VALUE io, VALUE buffer, size_t length, size_t offset);
 
 /**
- * Nonblocking write to the passed IO.
+ * Non-blocking write to the passed IO.
  *
  * @param[in]   scheduler    Target scheduler.
  * @param[out]  io           An io object to write to.
  * @param[in]   buffer       What to write.
  * @param[in]   length       Number of bytes to write.
+ * @param[in]   offset       The offset in the buffer to write from.
  * @retval      RUBY_Qundef  `scheduler` doesn't have `#io_write`.
  * @return      otherwise    What `scheduler.io_write` returns `[-errno, size]`.
  */
-VALUE rb_fiber_scheduler_io_write(VALUE scheduler, VALUE io, VALUE buffer, size_t length);
+VALUE rb_fiber_scheduler_io_write(VALUE scheduler, VALUE io, VALUE buffer, size_t length, size_t offset);
 
 /**
- * Nonblocking read from the passed IO at the specified offset.
+ * Non-blocking read from the passed IO at the specified offset.
  *
  * @param[in]   scheduler    Target scheduler.
  * @param[out]  io           An io object to read from.
- * @param[out]  buffer       Return buffer.
+ * @param[in]   from         The offset in the given IO to read the data from.
+ * @param[out]  buffer       The buffer to read the data to.
  * @param[in]   length       Requested number of bytes to read.
- * @param[in]   offset       The offset in the given IO to read the data from.
+ * @param[in]   offset       The offset in the buffer to read to.
  * @retval      RUBY_Qundef  `scheduler` doesn't have `#io_read`.
  * @return      otherwise    What `scheduler.io_read` returns.
  */
-VALUE rb_fiber_scheduler_io_pread(VALUE scheduler, VALUE io, VALUE buffer, size_t length, off_t offset);
+VALUE rb_fiber_scheduler_io_pread(VALUE scheduler, VALUE io, rb_off_t from, VALUE buffer, size_t length, size_t offset);
 
 /**
- * Nonblocking write to the passed IO at the specified offset.
+ * Non-blocking write to the passed IO at the specified offset.
  *
  * @param[in]   scheduler    Target scheduler.
  * @param[out]  io           An io object to write to.
- * @param[in]   buffer       What to write.
+ * @param[in]   from         The offset in the given IO to write the data to.
+ * @param[in]   buffer       The buffer to write the data from.
  * @param[in]   length       Number of bytes to write.
- * @param[in]   offset       The offset in the given IO to write the data to.
+ * @param[in]   offset       The offset in the buffer to write from.
  * @retval      RUBY_Qundef  `scheduler` doesn't have `#io_write`.
  * @return      otherwise    What `scheduler.io_write` returns.
  */
-VALUE rb_fiber_scheduler_io_pwrite(VALUE scheduler, VALUE io, VALUE buffer, size_t length, off_t offset);
+VALUE rb_fiber_scheduler_io_pwrite(VALUE scheduler, VALUE io, rb_off_t from, VALUE buffer, size_t length, size_t offset);
 
 /**
- * Nonblocking read from the passed IO using a native buffer.
+ * Non-blocking read from the passed IO using a native buffer.
  *
  * @param[in]   scheduler    Target scheduler.
  * @param[out]  io           An io object to read from.
  * @param[out]  buffer       Return buffer.
+ * @param[in]   size         Size of the return buffer.
  * @param[in]   length       Requested number of bytes to read.
  * @retval      RUBY_Qundef  `scheduler` doesn't have `#io_read`.
  * @return      otherwise    What `scheduler.io_read` returns.
@@ -300,11 +331,12 @@ VALUE rb_fiber_scheduler_io_pwrite(VALUE scheduler, VALUE io, VALUE buffer, size
 VALUE rb_fiber_scheduler_io_read_memory(VALUE scheduler, VALUE io, void *buffer, size_t size, size_t length);
 
 /**
- * Nonblocking write to the passed IO using a native buffer.
+ * Non-blocking write to the passed IO using a native buffer.
  *
  * @param[in]   scheduler    Target scheduler.
  * @param[out]  io           An io object to write to.
  * @param[in]   buffer       What to write.
+ * @param[in]   size         Size of the buffer.
  * @param[in]   length       Number of bytes to write.
  * @retval      RUBY_Qundef  `scheduler` doesn't have `#io_write`.
  * @return      otherwise    What `scheduler.io_write` returns.
@@ -312,7 +344,7 @@ VALUE rb_fiber_scheduler_io_read_memory(VALUE scheduler, VALUE io, void *buffer,
 VALUE rb_fiber_scheduler_io_write_memory(VALUE scheduler, VALUE io, const void *buffer, size_t size, size_t length);
 
 /**
- * Nonblocking close the given IO.
+ * Non-blocking close the given IO.
  *
  * @param[in]  scheduler    Target scheduler.
  * @param[in]  io           An io object to close.
@@ -322,7 +354,7 @@ VALUE rb_fiber_scheduler_io_write_memory(VALUE scheduler, VALUE io, const void *
 VALUE rb_fiber_scheduler_io_close(VALUE scheduler, VALUE io);
 
 /**
- * Nonblocking DNS lookup.
+ * Non-blocking DNS lookup.
  *
  * @param[in]  scheduler    Target scheduler.
  * @param[in]  hostname     A host name to query.
@@ -331,6 +363,12 @@ VALUE rb_fiber_scheduler_io_close(VALUE scheduler, VALUE io);
  */
 VALUE rb_fiber_scheduler_address_resolve(VALUE scheduler, VALUE hostname);
 
+/**
+ * Create and schedule a non-blocking fiber.
+ *
+ */
+VALUE rb_fiber_scheduler_fiber(VALUE scheduler, int argc, VALUE *argv, int kw_splat);
+
 RBIMPL_SYMBOL_EXPORT_END()
 
 #endif /* RUBY_FIBER_SCHEDULER_H */
diff --git a/include/ruby/internal/abi.h b/include/ruby/internal/abi.h
index 98a63927c5..44111a0055 100644
--- a/include/ruby/internal/abi.h
+++ b/include/ruby/internal/abi.h
@@ -1,6 +1,8 @@
 #ifndef RUBY_ABI_H
 #define RUBY_ABI_H
 
+#ifdef RUBY_ABI_VERSION /* should match the definition in config.h */
+
 /* This number represents Ruby's ABI version.
  *
  * In development Ruby, it should be bumped every time an ABI incompatible
@@ -19,16 +21,17 @@
  * - Backwards compatible refactors.
  * - Editing comments.
  *
- * In released versions of Ruby, this number should not be changed since teeny
+ * In released versions of Ruby, this number is not defined since teeny
  * versions of Ruby should guarantee ABI compatibility.
  */
-#define RUBY_ABI_VERSION 1
+#define RUBY_ABI_VERSION 3
 
 /* Windows does not support weak symbols so ruby_abi_version will not exist
  * in the shared library. */
-#if defined(HAVE_FUNC_WEAK) && !defined(_WIN32) && !defined(__MINGW32__)
+#if defined(HAVE_FUNC_WEAK) && !defined(_WIN32) && !defined(__MINGW32__) && !defined(__CYGWIN__)
 # define RUBY_DLN_CHECK_ABI
 #endif
+#endif  /* RUBY_ABI_VERSION */
 
 #ifdef RUBY_DLN_CHECK_ABI
 
@@ -39,7 +42,11 @@ extern "C" {
 RUBY_FUNC_EXPORTED unsigned long long __attribute__((weak))
 ruby_abi_version(void)
 {
+# ifdef RUBY_ABI_VERSION
     return RUBY_ABI_VERSION;
+# else
+    return 0;
+# endif
 }
 
 # ifdef __cplusplus
diff --git a/include/ruby/internal/anyargs.h b/include/ruby/internal/anyargs.h
index 9d8d16fdab..e4c6d155cc 100644
--- a/include/ruby/internal/anyargs.h
+++ b/include/ruby/internal/anyargs.h
@@ -84,12 +84,15 @@
 
 #elif defined(_WIN32) || defined(__CYGWIN__)
 # /* Skip due to [Bug #16134] */
+# define RBIMPL_CAST_FN_PTR 1
 
 #elif ! RBIMPL_HAS_ATTRIBUTE(transparent_union)
 # /* :TODO: improve here, please find a way to support. */
+# define RBIMPL_CAST_FN_PTR 1
 
 #elif ! defined(HAVE_VA_ARGS_MACRO)
 # /* :TODO: improve here, please find a way to support. */
+# define RBIMPL_CAST_FN_PTR 1
 
 #else
 # /** @cond INTERNAL_MACRO */
@@ -239,15 +242,16 @@
 # define RBIMPL_ANYARGS_DISPATCH_rb_define_method_13(n)           RBIMPL_ANYARGS_DISPATCH((n) == 13, rb_define_method_13,           RBIMPL_ANYARGS_DISPATCH_rb_define_method_12(n))
 # define RBIMPL_ANYARGS_DISPATCH_rb_define_method_14(n)           RBIMPL_ANYARGS_DISPATCH((n) == 14, rb_define_method_14,           RBIMPL_ANYARGS_DISPATCH_rb_define_method_13(n))
 # define RBIMPL_ANYARGS_DISPATCH_rb_define_method_15(n)           RBIMPL_ANYARGS_DISPATCH((n) == 15, rb_define_method_15,           RBIMPL_ANYARGS_DISPATCH_rb_define_method_14(n))
-# define RBIMPL_ANYARGS_DISPATCH_rb_define_singleton_method(n, f) RBIMPL_ANYARGS_DISPATCH(RBIMPL_CFUNC_IS_rb_f_notimplement(f), rb_define_singleton_method_m3, RBIMPL_ANYARGS_DISPATCH_rb_define_singleton_method_15(n))
-# define RBIMPL_ANYARGS_DISPATCH_rb_define_protected_method(n, f) RBIMPL_ANYARGS_DISPATCH(RBIMPL_CFUNC_IS_rb_f_notimplement(f), rb_define_protected_method_m3, RBIMPL_ANYARGS_DISPATCH_rb_define_protected_method_15(n))
-# define RBIMPL_ANYARGS_DISPATCH_rb_define_private_method(n, f)   RBIMPL_ANYARGS_DISPATCH(RBIMPL_CFUNC_IS_rb_f_notimplement(f), rb_define_private_method_m3,   RBIMPL_ANYARGS_DISPATCH_rb_define_private_method_15(n))
-# define RBIMPL_ANYARGS_DISPATCH_rb_define_module_function(n, f)  RBIMPL_ANYARGS_DISPATCH(RBIMPL_CFUNC_IS_rb_f_notimplement(f), rb_define_module_function_m3,  RBIMPL_ANYARGS_DISPATCH_rb_define_module_function_15(n))
-# define RBIMPL_ANYARGS_DISPATCH_rb_define_global_function(n, f)  RBIMPL_ANYARGS_DISPATCH(RBIMPL_CFUNC_IS_rb_f_notimplement(f), rb_define_global_function_m3,  RBIMPL_ANYARGS_DISPATCH_rb_define_global_function_15(n))
-# define RBIMPL_ANYARGS_DISPATCH_rb_define_method_id(n, f)        RBIMPL_ANYARGS_DISPATCH(RBIMPL_CFUNC_IS_rb_f_notimplement(f), rb_define_method_id_m3,        RBIMPL_ANYARGS_DISPATCH_rb_define_method_id_15(n))
-# define RBIMPL_ANYARGS_DISPATCH_rb_define_method(n, f)           RBIMPL_ANYARGS_DISPATCH(RBIMPL_CFUNC_IS_rb_f_notimplement(f), rb_define_method_m3,           RBIMPL_ANYARGS_DISPATCH_rb_define_method_15(n))
+# define RBIMPL_ANYARGS_DISPATCH_rb_define_singleton_method(n, f) RBIMPL_ANYARGS_DISPATCH(RBIMPL_CFUNC_IS_rb_f_notimplement(f), rb_define_singleton_method_notimpl, RBIMPL_ANYARGS_DISPATCH_rb_define_singleton_method_15(n))
+# define RBIMPL_ANYARGS_DISPATCH_rb_define_protected_method(n, f) RBIMPL_ANYARGS_DISPATCH(RBIMPL_CFUNC_IS_rb_f_notimplement(f), rb_define_protected_method_notimpl, RBIMPL_ANYARGS_DISPATCH_rb_define_protected_method_15(n))
+# define RBIMPL_ANYARGS_DISPATCH_rb_define_private_method(n, f)   RBIMPL_ANYARGS_DISPATCH(RBIMPL_CFUNC_IS_rb_f_notimplement(f), rb_define_private_method_notimpl,   RBIMPL_ANYARGS_DISPATCH_rb_define_private_method_15(n))
+# define RBIMPL_ANYARGS_DISPATCH_rb_define_module_function(n, f)  RBIMPL_ANYARGS_DISPATCH(RBIMPL_CFUNC_IS_rb_f_notimplement(f), rb_define_module_function_notimpl,  RBIMPL_ANYARGS_DISPATCH_rb_define_module_function_15(n))
+# define RBIMPL_ANYARGS_DISPATCH_rb_define_global_function(n, f)  RBIMPL_ANYARGS_DISPATCH(RBIMPL_CFUNC_IS_rb_f_notimplement(f), rb_define_global_function_notimpl,  RBIMPL_ANYARGS_DISPATCH_rb_define_global_function_15(n))
+# define RBIMPL_ANYARGS_DISPATCH_rb_define_method_id(n, f)        RBIMPL_ANYARGS_DISPATCH(RBIMPL_CFUNC_IS_rb_f_notimplement(f), rb_define_method_id_notimpl,        RBIMPL_ANYARGS_DISPATCH_rb_define_method_id_15(n))
+# define RBIMPL_ANYARGS_DISPATCH_rb_define_method(n, f)           RBIMPL_ANYARGS_DISPATCH(RBIMPL_CFUNC_IS_rb_f_notimplement(f), rb_define_method_notimpl,           RBIMPL_ANYARGS_DISPATCH_rb_define_method_15(n))
 # define RBIMPL_ANYARGS_ATTRSET(sym) RBIMPL_ATTR_MAYBE_UNUSED() RBIMPL_ATTR_NONNULL(()) RBIMPL_ATTR_WEAKREF(sym)
 # define RBIMPL_ANYARGS_DECL(sym, ...) \
+RBIMPL_ANYARGS_ATTRSET(sym) static void sym ## _notimpl(__VA_ARGS__, VALUE(*)(int, const VALUE *, VALUE, VALUE), int); \
 RBIMPL_ANYARGS_ATTRSET(sym) static void sym ## _m3(__VA_ARGS__, VALUE(*)(ANYARGS), int); \
 RBIMPL_ANYARGS_ATTRSET(sym) static void sym ## _m2(__VA_ARGS__, VALUE(*)(VALUE, VALUE), int); \
 RBIMPL_ANYARGS_ATTRSET(sym) static void sym ## _m1(__VA_ARGS__, VALUE(*)(int, union { VALUE *x; const VALUE *y; } __attribute__((__transparent_union__)), VALUE), int); \
@@ -347,6 +351,25 @@ RBIMPL_ANYARGS_DECL(rb_define_method, VALUE, const char *)
 
 #endif /* __cplusplus */
 
+#if defined(RBIMPL_CAST_FN_PTR) && !defined(__cplusplus)
+/* In C23, K&R style prototypes are gone and so `void foo(ANYARGS)` became
+ * equivalent to `void foo(void)` unlike in earlier versions. This is a problem
+ * for rb_define_* functions since that makes all valid functions one can pass
+ * trip -Wincompatible-pointer-types, which we treat as errors. This is mostly
+ * not a problem for the __builtin_choose_expr path, but outside of that we
+ * need to add a cast for compatibility.
+ */
+#define rb_define_method(klass, mid, func, arity)           rb_define_method((klass), (mid), (VALUE (*)(ANYARGS))(func), (arity))
+#define rb_define_method_id(klass, mid, func, arity)        rb_define_method_id((klass), (mid), (VALUE (*)(ANYARGS))(func), (arity))
+#define rb_define_singleton_method(obj, mid, func, arity)   rb_define_singleton_method((obj), (mid), (VALUE (*)(ANYARGS))(func), (arity))
+#define rb_define_protected_method(klass, mid, func, arity) rb_define_protected_method((klass), (mid), (VALUE (*)(ANYARGS))(func), (arity))
+#define rb_define_private_method(klass, mid, func, arity)   rb_define_private_method((klass), (mid), (VALUE (*)(ANYARGS))(func), (arity))
+#define rb_define_module_function(mod, mid, func, arity)    rb_define_module_function((mod), (mid), (VALUE (*)(ANYARGS))(func), (arity))
+#define rb_define_global_function(mid, func, arity)         rb_define_global_function((mid), (VALUE (*)(ANYARGS))(func), (arity))
+
+#undef RBIMPL_CAST_FN_PTR
+#endif /* defined(RBIMPL_CAST_FN_PTR) && !defined(__cplusplus) */
+
 /**
  * This  macro is  to properly  cast  a function  parameter of  *_define_method
  * family.  It  has been  around since  1.x era so  you can  maximise backwards
diff --git a/include/ruby/internal/arithmetic.h b/include/ruby/internal/arithmetic.h
index 3f7840c384..7ebb4a86f1 100644
--- a/include/ruby/internal/arithmetic.h
+++ b/include/ruby/internal/arithmetic.h
@@ -18,7 +18,8 @@
  *             Do not  expect for  instance `__VA_ARGS__` is  always available.
  *             We assume C99  for ruby itself but we don't  assume languages of
  *             extension libraries.  They could be written in C++98.
- * @brief      Conversion between C's arithmtic types and Ruby's numeric types.
+ * @brief      Conversion  between  C's arithmetic  types  and  Ruby's  numeric
+ *             types.
  */
 #include "ruby/internal/arithmetic/char.h"
 #include "ruby/internal/arithmetic/double.h"
diff --git a/include/ruby/internal/arithmetic/long.h b/include/ruby/internal/arithmetic/long.h
index 792f7be179..6b8fd8ffc3 100644
--- a/include/ruby/internal/arithmetic/long.h
+++ b/include/ruby/internal/arithmetic/long.h
@@ -115,7 +115,7 @@ RB_INT2FIX(long i)
     /* :NOTE: VALUE can be wider than long.  As j being unsigned, 2j+1 is fully
      * defined. Also it can be compiled into a single LEA instruction. */
     const unsigned long j = i;
-    const unsigned long k = 2 * j + RUBY_FIXNUM_FLAG;
+    const unsigned long k = (j << 1) + RUBY_FIXNUM_FLAG;
     const long          l = k;
     const SIGNED_VALUE  m = l; /* Sign extend */
     const VALUE         n = m;
diff --git a/include/ruby/internal/attr/nodiscard.h b/include/ruby/internal/attr/nodiscard.h
index 087192a7a8..c3ae118942 100644
--- a/include/ruby/internal/attr/nodiscard.h
+++ b/include/ruby/internal/attr/nodiscard.h
@@ -26,7 +26,7 @@
 
 /**
  * Wraps  (or simulates)  `[[nodiscard]]`.  In  C++  (at least  since C++20)  a
- * nodiscard attribute can  have a message why the result  shall not be ignoed.
+ * nodiscard attribute can  have a message why the result shall not be ignored.
  * However GCC attribute and SAL annotation cannot take them.
  */
 #if RBIMPL_HAS_CPP_ATTRIBUTE(nodiscard)
diff --git a/include/ruby/internal/attr/nonstring.h b/include/ruby/internal/attr/nonstring.h
new file mode 100644
index 0000000000..de26e926d4
--- /dev/null
+++ b/include/ruby/internal/attr/nonstring.h
@@ -0,0 +1,32 @@
+#ifndef RBIMPL_ATTR_NONSTRING_H                        /*-*-C++-*-vi:se ft=cpp:*/
+#define RBIMPL_ATTR_NONSTRING_H
+/**
+ * @file
+ * @author     Ruby developers <ruby-core@ruby-lang.org>
+ * @copyright  This  file  is   a  part  of  the   programming  language  Ruby.
+ *             Permission  is hereby  granted,  to  either redistribute  and/or
+ *             modify this file, provided that  the conditions mentioned in the
+ *             file COPYING are met.  Consult the file for details.
+ * @warning    Symbols   prefixed  with   either  `RBIMPL`   or  `rbimpl`   are
+ *             implementation details.   Don't take  them as canon.  They could
+ *             rapidly appear then vanish.  The name (path) of this header file
+ *             is also an  implementation detail.  Do not expect  it to persist
+ *             at the place it is now.  Developers are free to move it anywhere
+ *             anytime at will.
+ * @note       To  ruby-core:  remember  that   this  header  can  be  possibly
+ *             recursively included  from extension  libraries written  in C++.
+ *             Do not  expect for  instance `__VA_ARGS__` is  always available.
+ *             We assume C99  for ruby itself but we don't  assume languages of
+ *             extension libraries.  They could be written in C++98.
+ * @brief      Defines #RBIMPL_ATTR_NONSTRING.
+ */
+#include "ruby/internal/has/attribute.h"
+
+/** Wraps (or simulates) `__attribute__((nonstring))` */
+#if RBIMPL_HAS_ATTRIBUTE(nonstring)
+# define RBIMPL_ATTR_NONSTRING() __attribute__((nonstring))
+#else
+# define RBIMPL_ATTR_NONSTRING() /* void */
+#endif
+
+#endif /* RBIMPL_ATTR_NONSTRING_H */
diff --git a/include/ruby/internal/config.h b/include/ruby/internal/config.h
index 0c434e5b05..aa63376d7c 100644
--- a/include/ruby/internal/config.h
+++ b/include/ruby/internal/config.h
@@ -113,6 +113,8 @@
 # define UNALIGNED_WORD_ACCESS 1
 #elif defined(__powerpc64__)
 # define UNALIGNED_WORD_ACCESS 1
+#elif defined(__POWERPC__) // __POWERPC__ is defined for ppc and ppc64 on Darwin
+# define UNALIGNED_WORD_ACCESS 1
 #elif defined(__aarch64__)
 # define UNALIGNED_WORD_ACCESS 1
 #elif defined(__mc68020__)
diff --git a/include/ruby/internal/core/rarray.h b/include/ruby/internal/core/rarray.h
index d9e08839cb..c3bb40be25 100644
--- a/include/ruby/internal/core/rarray.h
+++ b/include/ruby/internal/core/rarray.h
@@ -131,7 +131,7 @@ enum ruby_rarray_flags {
      * store array elements.  It was a bad idea to expose this to them.
      */
 #if USE_RVARGC
-    RARRAY_EMBED_LEN_MASK  = RUBY_FL_USER8 | RUBY_FL_USER7 | RUBY_FL_USER6 |
+    RARRAY_EMBED_LEN_MASK  = RUBY_FL_USER9 | RUBY_FL_USER8 | RUBY_FL_USER7 | RUBY_FL_USER6 |
                                  RUBY_FL_USER5 | RUBY_FL_USER4 | RUBY_FL_USER3
 #else
     RARRAY_EMBED_LEN_MASK  = RUBY_FL_USER4 | RUBY_FL_USER3
@@ -488,14 +488,6 @@ rb_array_ptr_use_end(VALUE a,
  * This is an  implementation detail of #RARRAY_PTR_USE.  People do  not use it
  * directly.
  */
-#define RARRAY_PTR_USE_START(a) rb_array_ptr_use_start(a, 0)
-
-/**
- * @private
- *
- * This is an  implementation detail of #RARRAY_PTR_USE.  People do  not use it
- * directly.
- */
 #define RARRAY_PTR_USE_END(a) rb_array_ptr_use_end(a, 0)
 
 /**
@@ -527,22 +519,6 @@ rb_array_ptr_use_end(VALUE a,
     RBIMPL_RARRAY_STMT(0, ary, ptr_name, expr)
 
 /**
- * @private
- *
- * This is  an implementation  detail of #RARRAY_PTR_USE_TRANSIENT.   People do
- * not use it directly.
- */
-#define RARRAY_PTR_USE_START_TRANSIENT(a) rb_array_ptr_use_start(a, 1)
-
-/**
- * @private
- *
- * This is  an implementation  detail of #RARRAY_PTR_USE_TRANSIENT.   People do
- * not use it directly.
- */
-#define RARRAY_PTR_USE_END_TRANSIENT(a) rb_array_ptr_use_end(a, 1)
-
-/**
  * Identical to #RARRAY_PTR_USE, except the pointer can be a transient one.
  *
  * @param  ary       An object of ::RArray.
diff --git a/include/ruby/internal/core/rclass.h b/include/ruby/internal/core/rclass.h
index 13a33a28bd..b0b6bfc80c 100644
--- a/include/ruby/internal/core/rclass.h
+++ b/include/ruby/internal/core/rclass.h
@@ -26,9 +26,7 @@
 #include "ruby/internal/cast.h"
 
 /** @cond INTERNAL_MACRO */
-#define RMODULE_IS_OVERLAID              RMODULE_IS_OVERLAID
 #define RMODULE_IS_REFINEMENT            RMODULE_IS_REFINEMENT
-#define RMODULE_INCLUDED_INTO_REFINEMENT RMODULE_INCLUDED_INTO_REFINEMENT
 /** @endcond */
 
 /**
@@ -55,57 +53,12 @@
  * Why is it here, given RClass itself is not?
  */
 enum ruby_rmodule_flags {
-
-    /**
-     * This flag has something to do with refinements... I guess?  It is set on
-     * occasions  for modules  that are  refined by  refinements, but  it seems
-     * ...  nobody cares  about  such things?   Not sure  but  this flag  could
-     * perhaps be a write-only information.
-     */
-    RMODULE_IS_OVERLAID              = RUBY_FL_USER2,
-
     /**
      * This flag has something to do  with refinements.  A module created using
      * rb_mod_refine()  has this  flag set.   This  is the  bit which  controls
      * difference between normal inclusion versus refinements.
      */
-    RMODULE_IS_REFINEMENT            = RUBY_FL_USER3,
-
-    /**
-     * This flag  has something  to do  with refinements.  This  is set  when a
-     * (non-refinement)  module is  included into  another module,  which is  a
-     * refinement.  This amends the way `super` searches for a super method.
-     *
-     * ```ruby
-     * class Foo
-     *   def foo
-     *     "Foo"
-     *   end
-     * end
-     *
-     * module Bar
-     *   def foo
-     *     "[#{super}]" # this
-     *   end
-     * end
-     *
-     * module Baz
-     *   refine Foo do
-     *     include Bar
-     *     def foo
-     *       "<#{super}>"
-     *     end
-     *   end
-     * end
-     *
-     * using Baz
-     * Foo.new.foo # => "[<Foo>]"
-     * ```
-     *
-     * The  `super`  marked  with  "this"   comment  shall  look  for  overlaid
-     * `Foo#foo`, which is not the ordinal method lookup direction.
-     */
-    RMODULE_INCLUDED_INTO_REFINEMENT = RUBY_FL_USER4
+    RMODULE_IS_REFINEMENT            = RUBY_FL_USER3
 };
 
 struct RClass; /* Opaque, declared here for RCLASS() macro. */
diff --git a/include/ruby/internal/core/robject.h b/include/ruby/internal/core/robject.h
index f2028063a6..b1c2e1b0a9 100644
--- a/include/ruby/internal/core/robject.h
+++ b/include/ruby/internal/core/robject.h
@@ -37,16 +37,15 @@
 /**
  * Convenient casting macro.
  *
- * @param   obj  An object, which is in fact an ::RRegexp.
- * @return  The passed object casted to ::RRegexp.
+ * @param   obj  An object, which is in fact an ::RObject.
+ * @return  The passed object casted to ::RObject.
  */
 #define ROBJECT(obj)          RBIMPL_CAST((struct RObject *)(obj))
 /** @cond INTERNAL_MACRO */
 #define ROBJECT_EMBED_LEN_MAX ROBJECT_EMBED_LEN_MAX
 #define ROBJECT_EMBED         ROBJECT_EMBED
-#define ROBJECT_NUMIV         ROBJECT_NUMIV
+#define ROBJECT_IV_CAPACITY   ROBJECT_IV_CAPACITY
 #define ROBJECT_IVPTR         ROBJECT_IVPTR
-#define ROBJECT_IV_INDEX_TBL  ROBJECT_IV_INDEX_TBL
 /** @endcond */
 
 /**
@@ -75,6 +74,7 @@ enum ruby_robject_flags {
     ROBJECT_EMBED = RUBY_FL_USER1
 };
 
+#if !USE_RVARGC
 /**
  * This is an enum because GDB wants it (rather than a macro).  People need not
  * bother.
@@ -83,6 +83,7 @@ enum ruby_robject_consts {
     /** Max possible number of instance variables that can be embedded. */
     ROBJECT_EMBED_LEN_MAX = RBIMPL_EMBED_LEN_MAX_OF(VALUE)
 };
+#endif
 
 struct st_table;
 
@@ -103,13 +104,6 @@ struct RObject {
          * this pattern.
          */
         struct {
-
-            /**
-             * Number of instance variables.  This is per object; objects might
-             * differ in this field even if they have the identical classes.
-             */
-            uint32_t numiv;
-
             /** Pointer to a C array that holds instance variables. */
             VALUE *ivptr;
 
@@ -121,38 +115,35 @@ struct RObject {
              *
              * This is a shortcut for `RCLASS_IV_INDEX_TBL(rb_obj_class(obj))`.
              */
-            struct st_table *iv_index_tbl;
+            struct rb_id_table *iv_index_tbl;
         } heap;
 
-        /**
-         * Embedded instance  variables.  When  an object  is small  enough, it
+#if USE_RVARGC
+        /* Embedded instance variables. When an object is small enough, it
          * uses this area to store the instance variables.
+         *
+         * This is a length 1 array because:
+         *   1. GCC has a bug that does not optimize C flexible array members
+         *      (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102452)
+         *   2. Zero length arrays are not supported by all compilers
          */
+        VALUE ary[1];
+#else
+        /**
+        * Embedded instance  variables.  When  an object  is small  enough, it
+        * uses this area to store the instance variables.
+        */
         VALUE ary[ROBJECT_EMBED_LEN_MAX];
+#endif
     } as;
 };
 
-RBIMPL_ATTR_PURE_UNLESS_DEBUG()
-RBIMPL_ATTR_ARTIFICIAL()
-/**
- * Queries the number of instance variables.
- *
- * @param[in]  obj  Object in question.
- * @return     Its number of instance variables.
- * @pre        `obj` must be an instance of ::RObject.
- */
-static inline uint32_t
-ROBJECT_NUMIV(VALUE obj)
-{
-    RBIMPL_ASSERT_TYPE(obj, RUBY_T_OBJECT);
-
-    if (RB_FL_ANY_RAW(obj, ROBJECT_EMBED)) {
-        return ROBJECT_EMBED_LEN_MAX;
-    }
-    else {
-        return ROBJECT(obj)->as.heap.numiv;
-    }
-}
+/* Offsets for YJIT */
+#ifndef __cplusplus
+static const int32_t ROBJECT_OFFSET_AS_HEAP_IVPTR = offsetof(struct RObject, as.heap.ivptr);
+static const int32_t ROBJECT_OFFSET_AS_HEAP_IV_INDEX_TBL = offsetof(struct RObject, as.heap.iv_index_tbl);
+static const int32_t ROBJECT_OFFSET_AS_ARY = offsetof(struct RObject, as.ary);
+#endif
 
 RBIMPL_ATTR_PURE_UNLESS_DEBUG()
 RBIMPL_ATTR_ARTIFICIAL()
diff --git a/include/ruby/internal/encoding/ctype.h b/include/ruby/internal/encoding/ctype.h
index 64aaf0a990..05c314aeb3 100644
--- a/include/ruby/internal/encoding/ctype.h
+++ b/include/ruby/internal/encoding/ctype.h
@@ -36,8 +36,8 @@ RBIMPL_SYMBOL_EXPORT_BEGIN()
  * @param[in]  p          Pointer to a possibly-middle of a character.
  * @param[in]  end        End of the string.
  * @param[in]  enc        Encoding.
- * @retval     0          It isn't.
- * @retval     otherwise  It is.
+ * @retval     false      It isn't.
+ * @retval     true       It is.
  */
 static inline bool
 rb_enc_is_newline(const char *p,  const char *e, rb_encoding *enc)
@@ -53,11 +53,11 @@ rb_enc_is_newline(const char *p,  const char *e, rb_encoding *enc)
  * encoding.  The "character type" here is a set of macros defined in onigmo.h,
  * like `ONIGENC_CTYPE_PUNCT`.
  *
- * @param[in]  c    An `OnigCodePoint` value.
- * @param[in]  t    An `OnigCtype` value.
- * @param[in]  enc  A `rb_encoding*` value.
- * @retval     1    `c` is of `t` in `enc`.
- * @retval     0    Otherwise.
+ * @param[in]  c          An `OnigCodePoint` value.
+ * @param[in]  t          An `OnigCtype` value.
+ * @param[in]  enc        A `rb_encoding*` value.
+ * @retval     true       `c` is of `t` in `enc`.
+ * @retval     false      Otherwise.
  */
 static inline bool
 rb_enc_isctype(OnigCodePoint c, OnigCtype t, rb_encoding *enc)
@@ -68,10 +68,10 @@ rb_enc_isctype(OnigCodePoint c, OnigCtype t, rb_encoding *enc)
 /**
  * Identical to rb_isascii(), except it additionally takes an encoding.
  *
- * @param[in]  c    A code point.
- * @param[in]  enc  An encoding.
- * @retval     0    `c` is out of range of ASCII character set in `enc`.
- * @retval     1    Otherwise.
+ * @param[in]  c          A code point.
+ * @param[in]  enc        An encoding.
+ * @retval     false      `c` is out of range of ASCII character set in `enc`.
+ * @retval     true       Otherwise.
  *
  * @internal
  *
@@ -87,10 +87,10 @@ rb_enc_isascii(OnigCodePoint c, rb_encoding *enc)
 /**
  * Identical to rb_isalpha(), except it additionally takes an encoding.
  *
- * @param[in]  c    A code point.
- * @param[in]  enc  An encoding.
- * @retval     1    `enc` classifies `c` as "ALPHA".
- * @retval     0    Otherwise.
+ * @param[in]  c          A code point.
+ * @param[in]  enc        An encoding.
+ * @retval     true       `enc` classifies `c` as "ALPHA".
+ * @retval     false      Otherwise.
  */
 static inline bool
 rb_enc_isalpha(OnigCodePoint c, rb_encoding *enc)
@@ -101,10 +101,10 @@ rb_enc_isalpha(OnigCodePoint c, rb_encoding *enc)
 /**
  * Identical to rb_islower(), except it additionally takes an encoding.
  *
- * @param[in]  c    A code point.
- * @param[in]  enc  An encoding.
- * @retval     1    `enc` classifies `c` as "LOWER".
- * @retval     0    Otherwise.
+ * @param[in]  c          A code point.
+ * @param[in]  enc        An encoding.
+ * @retval     true       `enc` classifies `c` as "LOWER".
+ * @retval     false      Otherwise.
  */
 static inline bool
 rb_enc_islower(OnigCodePoint c, rb_encoding *enc)
@@ -115,10 +115,10 @@ rb_enc_islower(OnigCodePoint c, rb_encoding *enc)
 /**
  * Identical to rb_isupper(), except it additionally takes an encoding.
  *
- * @param[in]  c    A code point.
- * @param[in]  enc  An encoding.
- * @retval     1    `enc` classifies `c` as "UPPER".
- * @retval     0    Otherwise.
+ * @param[in]  c          A code point.
+ * @param[in]  enc        An encoding.
+ * @retval     true       `enc` classifies `c` as "UPPER".
+ * @retval     false      Otherwise.
  */
 static inline bool
 rb_enc_isupper(OnigCodePoint c, rb_encoding *enc)
@@ -127,12 +127,26 @@ rb_enc_isupper(OnigCodePoint c, rb_encoding *enc)
 }
 
 /**
+ * Identical to rb_iscntrl(), except it additionally takes an encoding.
+ *
+ * @param[in]  c          A code point.
+ * @param[in]  enc        An encoding.
+ * @retval     true       `enc` classifies `c` as "CNTRL".
+ * @retval     false      Otherwise.
+ */
+static inline bool
+rb_enc_iscntrl(OnigCodePoint c, rb_encoding *enc)
+{
+    return ONIGENC_IS_CODE_CNTRL(enc, c);
+}
+
+/**
  * Identical to rb_ispunct(), except it additionally takes an encoding.
  *
- * @param[in]  c    A code point.
- * @param[in]  enc  An encoding.
- * @retval     1    `enc` classifies `c` as "PUNCT".
- * @retval     0    Otherwise.
+ * @param[in]  c          A code point.
+ * @param[in]  enc        An encoding.
+ * @retval     true       `enc` classifies `c` as "PUNCT".
+ * @retval     false      Otherwise.
  */
 static inline bool
 rb_enc_ispunct(OnigCodePoint c, rb_encoding *enc)
@@ -143,10 +157,10 @@ rb_enc_ispunct(OnigCodePoint c, rb_encoding *enc)
 /**
  * Identical to rb_isalnum(), except it additionally takes an encoding.
  *
- * @param[in]  c    A code point.
- * @param[in]  enc  An encoding.
- * @retval     1    `enc` classifies `c` as "ANUM".
- * @retval     0    Otherwise.
+ * @param[in]  c          A code point.
+ * @param[in]  enc        An encoding.
+ * @retval     true       `enc` classifies `c` as "ANUM".
+ * @retval     false      Otherwise.
  */
 static inline bool
 rb_enc_isalnum(OnigCodePoint c, rb_encoding *enc)
@@ -157,10 +171,10 @@ rb_enc_isalnum(OnigCodePoint c, rb_encoding *enc)
 /**
  * Identical to rb_isprint(), except it additionally takes an encoding.
  *
- * @param[in]  c    A code point.
- * @param[in]  enc  An encoding.
- * @retval     1    `enc` classifies `c` as "PRINT".
- * @retval     0    Otherwise.
+ * @param[in]  c          A code point.
+ * @param[in]  enc        An encoding.
+ * @retval     true       `enc` classifies `c` as "PRINT".
+ * @retval     false      Otherwise.
  */
 static inline bool
 rb_enc_isprint(OnigCodePoint c, rb_encoding *enc)
@@ -171,10 +185,10 @@ rb_enc_isprint(OnigCodePoint c, rb_encoding *enc)
 /**
  * Identical to rb_isspace(), except it additionally takes an encoding.
  *
- * @param[in]  c    A code point.
- * @param[in]  enc  An encoding.
- * @retval     1    `enc` classifies `c` as "PRINT".
- * @retval     0    Otherwise.
+ * @param[in]  c          A code point.
+ * @param[in]  enc        An encoding.
+ * @retval     true       `enc` classifies `c` as "PRINT".
+ * @retval     false      Otherwise.
  */
 static inline bool
 rb_enc_isspace(OnigCodePoint c, rb_encoding *enc)
@@ -185,10 +199,10 @@ rb_enc_isspace(OnigCodePoint c, rb_encoding *enc)
 /**
  * Identical to rb_isdigit(), except it additionally takes an encoding.
  *
- * @param[in]  c    A code point.
- * @param[in]  enc  An encoding.
- * @retval     1    `enc` classifies `c` as "DIGIT".
- * @retval     0    Otherwise.
+ * @param[in]  c          A code point.
+ * @param[in]  enc        An encoding.
+ * @retval     true       `enc` classifies `c` as "DIGIT".
+ * @retval     false      Otherwise.
  */
 static inline bool
 rb_enc_isdigit(OnigCodePoint c, rb_encoding *enc)
@@ -235,6 +249,7 @@ RBIMPL_SYMBOL_EXPORT_END()
 #define rb_enc_isdigit    rb_enc_isdigit
 #define rb_enc_islower    rb_enc_islower
 #define rb_enc_isprint    rb_enc_isprint
+#define rb_enc_iscntrl    rb_enc_iscntrl
 #define rb_enc_ispunct    rb_enc_ispunct
 #define rb_enc_isspace    rb_enc_isspace
 #define rb_enc_isupper    rb_enc_isupper
diff --git a/include/ruby/internal/encoding/encoding.h b/include/ruby/internal/encoding/encoding.h
index 22deb8f8c9..4748ca806b 100644
--- a/include/ruby/internal/encoding/encoding.h
+++ b/include/ruby/internal/encoding/encoding.h
@@ -643,10 +643,12 @@ rb_enc_code_to_mbclen(int c, rb_encoding *enc)
  * Identical to rb_enc_uint_chr(),  except it writes back to  the passed buffer
  * instead of allocating one.
  *
- * @param[in]   c    Code point.
- * @param[out]  buf  Return buffer.
- * @param[in]   enc  Target encoding scheme.
- * @post        `c` is encoded according to `enc`, then written to `buf`.
+ * @param[in]  c          Code point.
+ * @param[out] buf        Return buffer.
+ * @param[in]  enc        Target encoding scheme.
+ * @retval     <= 0       `c` is invalid in `enc`.
+ * @return     otherwise  Number of bytes written to `buf`.
+ * @post       `c` is encoded according to `enc`, then written to `buf`.
  *
  * @internal
  *
diff --git a/include/ruby/internal/encoding/transcode.h b/include/ruby/internal/encoding/transcode.h
index 60c96a41c9..7f26d2eae9 100644
--- a/include/ruby/internal/encoding/transcode.h
+++ b/include/ruby/internal/encoding/transcode.h
@@ -476,16 +476,16 @@ enum ruby_econv_flag_type {
     RUBY_ECONV_UNDEF_HEX_CHARREF                = 0x00000030,
 
     /** Decorators are there. */
-    RUBY_ECONV_DECORATOR_MASK                   = 0x0000ff00,
+    RUBY_ECONV_DECORATOR_MASK                   = 0x0001ff00,
 
     /** Newline converters are there. */
-    RUBY_ECONV_NEWLINE_DECORATOR_MASK           = 0x00003f00,
+    RUBY_ECONV_NEWLINE_DECORATOR_MASK           = 0x00007f00,
 
     /** (Unclear; seems unused). */
     RUBY_ECONV_NEWLINE_DECORATOR_READ_MASK      = 0x00000f00,
 
     /** (Unclear; seems unused). */
-    RUBY_ECONV_NEWLINE_DECORATOR_WRITE_MASK     = 0x00003000,
+    RUBY_ECONV_NEWLINE_DECORATOR_WRITE_MASK     = 0x00007000,
 
     /** Universal newline mode. */
     RUBY_ECONV_UNIVERSAL_NEWLINE_DECORATOR      = 0x00000100,
@@ -496,11 +496,14 @@ enum ruby_econv_flag_type {
     /** CRLF to CR conversion shall happen. */
     RUBY_ECONV_CR_NEWLINE_DECORATOR             = 0x00002000,
 
+    /** CRLF to LF conversion shall happen. */
+    RUBY_ECONV_LF_NEWLINE_DECORATOR             = 0x00004000,
+
     /** Texts shall be XML-escaped. */
-    RUBY_ECONV_XML_TEXT_DECORATOR               = 0x00004000,
+    RUBY_ECONV_XML_TEXT_DECORATOR               = 0x00008000,
 
     /** Texts shall be AttrValue escaped */
-    RUBY_ECONV_XML_ATTR_CONTENT_DECORATOR       = 0x00008000,
+    RUBY_ECONV_XML_ATTR_CONTENT_DECORATOR       = 0x00010000,
 
     /** (Unclear; seems unused). */
     RUBY_ECONV_STATEFUL_DECORATOR_MASK          = 0x00f00000,
@@ -529,6 +532,7 @@ enum ruby_econv_flag_type {
 #define ECONV_UNIVERSAL_NEWLINE_DECORATOR       RUBY_ECONV_UNIVERSAL_NEWLINE_DECORATOR  /**< @old{RUBY_ECONV_UNIVERSAL_NEWLINE_DECORATOR} */
 #define ECONV_CRLF_NEWLINE_DECORATOR            RUBY_ECONV_CRLF_NEWLINE_DECORATOR       /**< @old{RUBY_ECONV_CRLF_NEWLINE_DECORATOR} */
 #define ECONV_CR_NEWLINE_DECORATOR              RUBY_ECONV_CR_NEWLINE_DECORATOR         /**< @old{RUBY_ECONV_CR_NEWLINE_DECORATOR} */
+#define ECONV_LF_NEWLINE_DECORATOR              RUBY_ECONV_LF_NEWLINE_DECORATOR         /**< @old{RUBY_ECONV_LF_NEWLINE_DECORATOR} */
 #define ECONV_XML_TEXT_DECORATOR                RUBY_ECONV_XML_TEXT_DECORATOR           /**< @old{RUBY_ECONV_XML_TEXT_DECORATOR} */
 #define ECONV_XML_ATTR_CONTENT_DECORATOR        RUBY_ECONV_XML_ATTR_CONTENT_DECORATOR   /**< @old{RUBY_ECONV_XML_ATTR_CONTENT_DECORATOR} */
 #define ECONV_STATEFUL_DECORATOR_MASK           RUBY_ECONV_STATEFUL_DECORATOR_MASK      /**< @old{RUBY_ECONV_STATEFUL_DECORATOR_MASK} */
@@ -543,10 +547,10 @@ enum ruby_econv_flag_type {
      */
 
     /** Indicates the input is a part of much larger one. */
-    RUBY_ECONV_PARTIAL_INPUT                    = 0x00010000,
+    RUBY_ECONV_PARTIAL_INPUT                    = 0x00020000,
 
     /** Instructs the converter to stop after output. */
-    RUBY_ECONV_AFTER_OUTPUT                     = 0x00020000,
+    RUBY_ECONV_AFTER_OUTPUT                     = 0x00040000,
 #define ECONV_PARTIAL_INPUT                     RUBY_ECONV_PARTIAL_INPUT /**< @old{RUBY_ECONV_PARTIAL_INPUT} */
 #define ECONV_AFTER_OUTPUT                      RUBY_ECONV_AFTER_OUTPUT  /**< @old{RUBY_ECONV_AFTER_OUTPUT} */
 
diff --git a/include/ruby/internal/eval.h b/include/ruby/internal/eval.h
index 34a53849da..5bcbb97746 100644
--- a/include/ruby/internal/eval.h
+++ b/include/ruby/internal/eval.h
@@ -28,10 +28,12 @@ RBIMPL_SYMBOL_EXPORT_BEGIN()
 
 RBIMPL_ATTR_NONNULL(())
 /**
- * Evaluates the given string in an isolated binding.
+ * Evaluates the given string.
  *
- * Here  "isolated"  means  that  the   binding  does  not  inherit  any  other
- * bindings.  This behaves same as the binding for required libraries.
+ * In case  it is called  from within a  C-backended method, the  evaluation is
+ * done under  the current binding.  However  there can be no  method.  On such
+ * situation this  function evaluates  in an  isolated binding,  like `require`
+ * runs in a separate one.
  *
  * `__FILE__`  will  be  `"(eval)"`,  and  `__LINE__`  starts  from  1  in  the
  * evaluation.
@@ -39,6 +41,31 @@ RBIMPL_ATTR_NONNULL(())
  * @param[in]  str            Ruby code to evaluate.
  * @exception  rb_eException  Raises an exception on error.
  * @return     The evaluated result.
+ *
+ * @internal
+ *
+ * @shyouhei's old tale about the birth and growth of this function:
+ *
+ * At  the beginning,  there  was no  rb_eval_string().   @shyouhei heard  that
+ * @shugo, author of  Apache httpd's mod_ruby module, requested  @matz for this
+ * API.  He wanted a way so that mod_ruby can evaluate ruby scripts one by one,
+ * separately, in each different contexts.  So  this function was made.  It was
+ * designed to be a global interpreter entry point like ruby_run_node().
+ *
+ * The  way it  is implemented  however  allows extension  libraries (not  just
+ * programs like  Apache httpd) to call  this function.  Because its  name says
+ * nothing  about the  initial design,  people  started to  think of  it as  an
+ * orthodox  way  to  call  ruby  level  `eval`  method  from  their  extension
+ * libraries.  Even our `extension.rdoc` has had a description of this function
+ * basically according to this understanding.
+ *
+ * The old  (mod_ruby like) usage still  works.  But over time,  usages of this
+ * function from extension libraries got  popular, while mod_ruby faded out; is
+ * no  longer maintained  now.  Devs  decided to  actively support  both.  This
+ * function  now auto-detects  how  it is  called, and  switches  how it  works
+ * depending on it.
+ *
+ * @see https://bugs.ruby-lang.org/issues/18780
  */
 VALUE rb_eval_string(const char *str);
 
diff --git a/include/ruby/internal/fl_type.h b/include/ruby/internal/fl_type.h
index c51bd2e9d9..7383426b23 100644
--- a/include/ruby/internal/fl_type.h
+++ b/include/ruby/internal/fl_type.h
@@ -941,21 +941,8 @@ RB_OBJ_FREEZE_RAW(VALUE obj)
     RB_FL_SET_RAW(obj, RUBY_FL_FREEZE);
 }
 
-/**
- * Prevents further modifications to the given object.  ::rb_eFrozenError shall
- * be raised if modification is attempted.
- *
- * @param[out]  x  Object in question.
- */
-static inline void
-rb_obj_freeze_inline(VALUE x)
-{
-    if (RB_FL_ABLE(x)) {
-        RB_OBJ_FREEZE_RAW(x);
-        if (RBASIC_CLASS(x) && !(RBASIC(x)->flags & RUBY_FL_SINGLETON)) {
-            rb_freeze_singleton_class(x);
-        }
-    }
-}
+RUBY_SYMBOL_EXPORT_BEGIN
+void rb_obj_freeze_inline(VALUE obj);
+RUBY_SYMBOL_EXPORT_END
 
 #endif /* RBIMPL_FL_TYPE_H */
diff --git a/include/ruby/internal/gc.h b/include/ruby/internal/gc.h
index 66fc14e511..054e4b0f9c 100644
--- a/include/ruby/internal/gc.h
+++ b/include/ruby/internal/gc.h
@@ -26,10 +26,15 @@
 RBIMPL_SYMBOL_EXPORT_BEGIN()
 
 /**
- * Inform the garbage collector that `valptr` points to a live Ruby object that
- * should not be moved. Note that extensions should use this API on global
- * constants instead of assuming constants defined in Ruby are always alive.
- * Ruby code can remove global constants.
+ * Inform the garbage  collector that the global or static  variable pointed by
+ * `valptr` stores  a live  Ruby object  that should not  be moved.   Note that
+ * extensions  should use  this API  on  global constants  instead of  assuming
+ * constants defined  in Ruby are  always alive.   Ruby code can  remove global
+ * constants.
+ *
+ * Because this  registration itself has  a possibility  to trigger a  GC, this
+ * function  must be  called  before any  GC-able objects  is  assigned to  the
+ * address pointed by `valptr`.
  */
 void rb_gc_register_address(VALUE *valptr);
 
diff --git a/include/ruby/internal/intern/array.h b/include/ruby/internal/intern/array.h
index 17964bf810..2262c6f0c6 100644
--- a/include/ruby/internal/intern/array.h
+++ b/include/ruby/internal/intern/array.h
@@ -107,14 +107,14 @@ VALUE rb_ary_new_from_args(long n, ...);
 VALUE rb_ary_new_from_values(long n, const VALUE *elts);
 
 /**
- * Allocates a  "temporary" array.   This is  a hidden  empty array.   Handy on
- * occasions.
+ * Allocates a hidden (no class) empty array.
  *
  * @param[in]  capa  Designed capacity of the array.
  * @return     A hidden, empty array.
  * @see        rb_obj_hide()
  */
-VALUE rb_ary_tmp_new(long capa);
+VALUE rb_ary_hidden_new(long capa);
+#define rb_ary_tmp_new rb_ary_hidden_new
 
 /**
  * Destroys the given array for no reason.
diff --git a/include/ruby/internal/intern/class.h b/include/ruby/internal/intern/class.h
index 2181ab93c7..0fb2d001bc 100644
--- a/include/ruby/internal/intern/class.h
+++ b/include/ruby/internal/intern/class.h
@@ -200,6 +200,18 @@ VALUE rb_class_descendants(VALUE klass);
  */
 VALUE rb_class_subclasses(VALUE klass);
 
+
+/**
+ *  Returns the attached object for a singleton class.
+ *  If the given class is not a singleton class, raises a TypeError.
+ *
+ * @param[in]  klass A class.
+ * @return     The object which has the singleton class `klass`.
+ *
+ * @internal
+ */
+VALUE rb_class_attached_object(VALUE klass);
+
 /**
  * Generates an array of symbols, which are the list of method names defined in
  * the passed class.
diff --git a/include/ruby/internal/intern/cont.h b/include/ruby/internal/intern/cont.h
index 37493009f5..32647f48aa 100644
--- a/include/ruby/internal/intern/cont.h
+++ b/include/ruby/internal/intern/cont.h
@@ -39,6 +39,28 @@ RBIMPL_SYMBOL_EXPORT_BEGIN()
 VALUE rb_fiber_new(rb_block_call_func_t func, VALUE callback_obj);
 
 /**
+ * Creates a Fiber instance from a C-backended block with the specified
+ * storage.
+ *
+ * If the given storage is Qundef or Qtrue, this function is equivalent to
+ * rb_fiber_new() which inherits storage from the current fiber.
+ *
+ * Specifying Qtrue is experimental and may be changed in the future.
+ *
+ * If the given storage is Qnil, this function will lazy initialize the
+ * internal storage which starts of empty (without any inheritance).
+ *
+ * Otherwise, the given storage is used as the internal storage.
+ *
+ * @param[in]  func          A function, to become the fiber's body.
+ * @param[in]  callback_obj  Passed as-is to `func`.
+ * @param[in]  storage       The way to set up the storage for the fiber.
+ * @return     An allocated  new instance  of rb_cFiber, which  is ready  to be
+ *             "resume"d.
+ */
+VALUE rb_fiber_new_storage(rb_block_call_func_t func, VALUE callback_obj, VALUE storage);
+
+/**
  * Queries  the fiber  which  is  calling this  function.   Any ruby  execution
  * context has its fiber, either explicitly or implicitly.
  *
diff --git a/include/ruby/internal/intern/file.h b/include/ruby/internal/intern/file.h
index 2dc60c7ba7..79820fdc61 100644
--- a/include/ruby/internal/intern/file.h
+++ b/include/ruby/internal/intern/file.h
@@ -206,7 +206,7 @@ int rb_is_absolute_path(const char *path);
  *              unpredictable.  POSIX's `<sys/stat.h>` states  that "the use of
  *              this field is unspecified" then.
  */
-off_t rb_file_size(VALUE file);
+rb_off_t rb_file_size(VALUE file);
 
 RBIMPL_SYMBOL_EXPORT_END()
 
diff --git a/include/ruby/internal/intern/gc.h b/include/ruby/internal/intern/gc.h
index e7b8008729..2ee1d257db 100644
--- a/include/ruby/internal/intern/gc.h
+++ b/include/ruby/internal/intern/gc.h
@@ -26,7 +26,7 @@
 # include <stddef.h>                       /* size_t */
 #endif
 
-#if HAVE_SYS_TYPES_H
+#ifdef HAVE_SYS_TYPES_H
 # include <sys/types.h>                    /* ssize_t */
 #endif
 
@@ -71,7 +71,7 @@ RBIMPL_ATTR_NONNULL((1))
  *              addressable.
  * @param[out]  start  Pointer to an array of objects.
  * @param[out]  end    Pointer that terminates the array of objects.
- * @post        Objects from `start` to `end`, both inclusive, are marked.
+ * @post        Objects from `start` (included) to `end` (excluded) are marked.
  *
  * @internal
  *
diff --git a/include/ruby/internal/intern/hash.h b/include/ruby/internal/intern/hash.h
index 3cce7f61c7..af8dfd5d8f 100644
--- a/include/ruby/internal/intern/hash.h
+++ b/include/ruby/internal/intern/hash.h
@@ -107,6 +107,17 @@ VALUE rb_hash(VALUE obj);
 VALUE rb_hash_new(void);
 
 /**
+ * Identical to rb_hash_new(), except it additionally specifies how many keys
+ * it is expected to contain. This way you can create a hash that is large enough
+ * for your need. For large hashes it means it won't need to be reallocated and
+ * rehashed as much, improving performance.
+ *
+ * @param[in]  capa  Designed capacity of the hash.
+ * @return     An empty Hash, whose capacity is `capa`.
+ */
+VALUE rb_hash_new_capa(long capa);
+
+/**
  * Duplicates a hash.
  *
  * @param[in]  hash  An instance of ::rb_cHash.
diff --git a/include/ruby/internal/intern/object.h b/include/ruby/internal/intern/object.h
index 19af49b140..b9ffa57c06 100644
--- a/include/ruby/internal/intern/object.h
+++ b/include/ruby/internal/intern/object.h
@@ -92,8 +92,8 @@ VALUE rb_class_new_instance_kw(int argc, const VALUE *argv, VALUE klass, int kw_
  *
  * @param[in]  lhs          Comparison left hand side.
  * @param[in]  rhs          Comparison right hand side.
- * @retval     RUBY_Qtrue   They are equal.
- * @retval     RUBY_Qfalse  Otherwise.
+ * @retval     non-zero     They are equal.
+ * @retval     0            Otherwise.
  * @note       This  function  actually  calls `lhs.eql?(rhs)`  so  you  cannot
  *             implement your class' `#eql?` method using it.
  */
diff --git a/include/ruby/internal/intern/select/posix.h b/include/ruby/internal/intern/select/posix.h
index 5f828e66e2..0a9b0b2e51 100644
--- a/include/ruby/internal/intern/select/posix.h
+++ b/include/ruby/internal/intern/select/posix.h
@@ -136,7 +136,7 @@ rb_fd_max(const rb_fdset_t *f)
 }
 
 /** @cond INTERNAL_MACRO */
-/* :FIXME: What are these?  They don't exist for shibling implementations. */
+/* :FIXME: What are these?  They don't exist for sibling implementations. */
 #define rb_fd_init_copy(d, s) (*(d) = *(s))
 #define rb_fd_term(f)   ((void)(f))
 /** @endcond */
diff --git a/include/ruby/internal/memory.h b/include/ruby/internal/memory.h
index aa3464465d..6884db195d 100644
--- a/include/ruby/internal/memory.h
+++ b/include/ruby/internal/memory.h
@@ -287,12 +287,12 @@ typedef uint128_t DSIZE_T;
     RBIMPL_CAST((type *)alloca(rbimpl_size_mul_or_raise(sizeof(type), (n))))
 
 /**
- * Identical to #RB_ALLOCV_N(), except it  implicitly assumes the type of array
- * is ::VALUE.
+ * Identical to #RB_ALLOCV_N(), except that it allocates a number of bytes and
+ * returns a void* .
  *
  * @param   v  A variable to hold the just-in-case opaque Ruby object.
  * @param   n  Size of allocation, in bytes.
- * @return  An array of `n` bytes of ::VALUE.
+ * @return  A void pointer to `n` bytes storage.
  * @note    `n` may be evaluated twice.
  */
 #define RB_ALLOCV(v, n)        \
@@ -363,7 +363,7 @@ typedef uint128_t DSIZE_T;
  * @return  `p1`.
  * @post    First `n` elements of `p2` are copied into `p1`.
  */
-#define MEMCPY(p1,p2,type,n) memcpy((p1), (p2), rbimpl_size_mul_or_raise(sizeof(type), (n)))
+#define MEMCPY(p1,p2,type,n) ruby_nonempty_memcpy((p1), (p2), rbimpl_size_mul_or_raise(sizeof(type), (n)))
 
 /**
  * Handy macro to call memmove.
@@ -644,7 +644,6 @@ rb_alloc_tmp_buffer2(volatile VALUE *store, long count, size_t elsize)
     return rb_alloc_tmp_buffer_with_count(store, total_size, cnt);
 }
 
-#if ! defined(__MINGW32__) && ! defined(__DOXYGEN__)
 RBIMPL_SYMBOL_EXPORT_BEGIN()
 RBIMPL_ATTR_NOALIAS()
 RBIMPL_ATTR_NONNULL((1))
@@ -663,8 +662,5 @@ ruby_nonempty_memcpy(void *dest, const void *src, size_t n)
     }
 }
 RBIMPL_SYMBOL_EXPORT_END()
-#undef memcpy
-#define memcpy ruby_nonempty_memcpy
-#endif
 
 #endif /* RBIMPL_MEMORY_H */
diff --git a/include/ruby/internal/scan_args.h b/include/ruby/internal/scan_args.h
index cf5b18f77d..1ed2bf6368 100644
--- a/include/ruby/internal/scan_args.h
+++ b/include/ruby/internal/scan_args.h
@@ -100,7 +100,7 @@ RBIMPL_ATTR_NONNULL((2, 3))
  * param-arg-spec        := pre-arg-spec [post-arg-spec] / post-arg-spec /
  *                          pre-opt-post-arg-spec
  * pre-arg-spec          := num-of-leading-mandatory-args
-                            [num-of-optional-args]
+ *                          [num-of-optional-args]
  * post-arg-spec         := sym-for-variable-length-args
  *                          [num-of-trailing-mandatory-args]
  * pre-opt-post-arg-spec := num-of-leading-mandatory-args num-of-optional-args
diff --git a/include/ruby/internal/special_consts.h b/include/ruby/internal/special_consts.h
index 38934e4da3..dc0a6b41d6 100644
--- a/include/ruby/internal/special_consts.h
+++ b/include/ruby/internal/special_consts.h
@@ -76,6 +76,8 @@
 #define RB_SPECIAL_CONST_P RB_SPECIAL_CONST_P
 #define RB_STATIC_SYM_P    RB_STATIC_SYM_P
 #define RB_TEST            RB_TEST
+#define RB_UNDEF_P         RB_UNDEF_P
+#define RB_NIL_OR_UNDEF_P  RB_NIL_OR_UNDEF_P
 /** @endcond */
 
 /** special constants - i.e. non-zero and non-fixnum constants */
@@ -94,9 +96,9 @@ ruby_special_consts {
     RUBY_SYMBOL_FLAG,           /**< Flag to denote a static symbol. */
 #elif USE_FLONUM
     RUBY_Qfalse         = 0x00, /* ...0000 0000 */
+    RUBY_Qnil           = 0x04, /* ...0000 0100 */
     RUBY_Qtrue          = 0x14, /* ...0001 0100 */
-    RUBY_Qnil           = 0x08, /* ...0000 1000 */
-    RUBY_Qundef         = 0x34, /* ...0011 0100 */
+    RUBY_Qundef         = 0x24, /* ...0010 0100 */
     RUBY_IMMEDIATE_MASK = 0x07, /* ...0000 0111 */
     RUBY_FIXNUM_FLAG    = 0x01, /* ...xxxx xxx1 */
     RUBY_FLONUM_MASK    = 0x03, /* ...0000 0011 */
@@ -104,14 +106,14 @@ ruby_special_consts {
     RUBY_SYMBOL_FLAG    = 0x0c, /* ...xxxx 1100 */
 #else
     RUBY_Qfalse         = 0x00, /* ...0000 0000 */
-    RUBY_Qtrue          = 0x02, /* ...0000 0010 */
-    RUBY_Qnil           = 0x04, /* ...0000 0100 */
-    RUBY_Qundef         = 0x06, /* ...0000 0110 */
+    RUBY_Qnil           = 0x02, /* ...0000 0010 */
+    RUBY_Qtrue          = 0x06, /* ...0000 0110 */
+    RUBY_Qundef         = 0x0a, /* ...0000 1010 */
     RUBY_IMMEDIATE_MASK = 0x03, /* ...0000 0011 */
     RUBY_FIXNUM_FLAG    = 0x01, /* ...xxxx xxx1 */
     RUBY_FLONUM_MASK    = 0x00, /* any values ANDed with FLONUM_MASK cannot be FLONUM_FLAG */
     RUBY_FLONUM_FLAG    = 0x02, /* ...0000 0010 */
-    RUBY_SYMBOL_FLAG    = 0x0e, /* ...0000 1110 */
+    RUBY_SYMBOL_FLAG    = 0x0e, /* ...xxxx 1110 */
 #endif
 
     RUBY_SPECIAL_SHIFT  = 8 /**< Least significant 8 bits are reserved. */
@@ -136,12 +138,21 @@ static inline bool
 RB_TEST(VALUE obj)
 {
     /*
+     * if USE_FLONUM
      *  Qfalse:  ....0000 0000
-     *  Qnil:    ....0000 1000
-     * ~Qnil:    ....1111 0111
+     *  Qnil:    ....0000 0100
+     * ~Qnil:    ....1111 1011
      *  v        ....xxxx xxxx
      * ----------------------------
-     *  RTEST(v) ....xxxx 0xxx
+     *  RTEST(v) ....xxxx x0xx
+     *
+     * if ! USE_FLONUM
+     *  Qfalse:  ....0000 0000
+     *  Qnil:    ....0000 0010
+     * ~Qnil:    ....1111 1101
+     *  v        ....xxxx xxxx
+     * ----------------------------
+     *  RTEST(v) ....xxxx xx0x
      *
      *  RTEST(v) can be 0 if and only if (v == Qfalse || v == Qnil).
      */
@@ -168,6 +179,62 @@ RBIMPL_ATTR_CONST()
 RBIMPL_ATTR_CONSTEXPR(CXX11)
 RBIMPL_ATTR_ARTIFICIAL()
 /**
+ * Checks if the given object is undef.
+ *
+ * @param[in]  obj    An arbitrary ruby object.
+ * @retval     true   `obj` is ::RUBY_Qundef.
+ * @retval     false  Anything else.
+ */
+static inline bool
+RB_UNDEF_P(VALUE obj)
+{
+    return obj == RUBY_Qundef;
+}
+
+RBIMPL_ATTR_CONST()
+RBIMPL_ATTR_CONSTEXPR(CXX14)
+RBIMPL_ATTR_ARTIFICIAL()
+/**
+ * Checks if the given object is nil or undef.  Can be used to see if
+ * a keyword argument is not given or given `nil`.
+ *
+ * @param[in]  obj    An arbitrary ruby object.
+ * @retval     true   `obj` is ::RUBY_Qnil or ::RUBY_Qundef.
+ * @retval     false  Anything else.
+ */
+static inline bool
+RB_NIL_OR_UNDEF_P(VALUE obj)
+{
+    /*
+     * if USE_FLONUM
+     *  Qundef:       ....0010 0100
+     *  Qnil:         ....0000 0100
+     *  mask:         ....1101 1111
+     *  common_bits:  ....0000 0100
+     * ---------------------------------
+     *  Qnil & mask   ....0000 0100
+     *  Qundef & mask ....0000 0100
+     *
+     * if ! USE_FLONUM
+     *  Qundef:       ....0000 1010
+     *  Qnil:         ....0000 0010
+     *  mask:         ....1111 0111
+     *  common_bits:  ....0000 0010
+     * ----------------------------
+     *  Qnil & mask   ....0000 0010
+     *  Qundef & mask ....0000 0010
+     *
+     *  NIL_OR_UNDEF_P(v) can be true only when v is Qundef or Qnil.
+     */
+    const VALUE mask = ~(RUBY_Qundef ^ RUBY_Qnil);
+    const VALUE common_bits = RUBY_Qundef & RUBY_Qnil;
+    return (obj & mask) == common_bits;
+}
+
+RBIMPL_ATTR_CONST()
+RBIMPL_ATTR_CONSTEXPR(CXX11)
+RBIMPL_ATTR_ARTIFICIAL()
+/**
  * Checks if the given object is a so-called Fixnum.
  *
  * @param[in]  obj    An arbitrary ruby object.
@@ -259,7 +326,7 @@ RBIMPL_ATTR_ARTIFICIAL()
 static inline bool
 RB_SPECIAL_CONST_P(VALUE obj)
 {
-    return RB_IMMEDIATE_P(obj) || ! RB_TEST(obj);
+    return RB_IMMEDIATE_P(obj) || obj == RUBY_Qfalse;
 }
 
 RBIMPL_ATTR_CONST()
diff --git a/include/ruby/io.h b/include/ruby/io.h
index 36857db8f8..88029b1bb9 100644
--- a/include/ruby/io.h
+++ b/include/ruby/io.h
@@ -55,12 +55,23 @@
 #include "ruby/internal/value.h"
 #include "ruby/backward/2/attributes.h" /* PACKED_STRUCT_UNALIGNED */
 
+// IO#wait, IO#wait_readable, IO#wait_writable, IO#wait_priority are defined by this implementation.
+#define RUBY_IO_WAIT_METHODS
+
+// Used as the default timeout argument to `rb_io_wait` to use the `IO#timeout` value.
+#define RUBY_IO_TIMEOUT_DEFAULT Qnil
+
 RBIMPL_SYMBOL_EXPORT_BEGIN()
 
 struct stat;
 struct timeval;
 
 /**
+ * Indicates that a timeout has occurred while performing an IO operation.
+ */
+RUBY_EXTERN VALUE rb_eIOTimeoutError;
+
+/**
  * Type of events that an IO can wait.
  *
  * @internal
@@ -95,6 +106,34 @@ PACKED_STRUCT_UNALIGNED(struct rb_io_buffer_t {
 /** @alias{rb_io_buffer_t} */
 typedef struct rb_io_buffer_t rb_io_buffer_t;
 
+/** Decomposed encoding flags (e.g. `"enc:enc2""`). */
+/*
+ * enc  enc2 read action                      write action
+ * NULL NULL force_encoding(default_external) write the byte sequence of str
+ * e1   NULL force_encoding(e1)               convert str.encoding to e1
+ * e1   e2   convert from e2 to e1            convert str.encoding to e2
+ */
+struct rb_io_enc_t {
+    /** Internal encoding. */
+    rb_encoding *enc;
+    /** External encoding. */
+    rb_encoding *enc2;
+    /**
+     * Flags.
+     *
+     * @see enum ::ruby_econv_flag_type
+     */
+    int ecflags;
+    /**
+     * Flags as Ruby hash.
+     *
+     * @internal
+     *
+     * This is set.  But used from nowhere maybe?
+     */
+    VALUE ecopts;
+};
+
 /** Ruby's IO, metadata and buffers. */
 typedef struct rb_io_t {
 
@@ -138,36 +177,7 @@ typedef struct rb_io_t {
      */
     VALUE tied_io_for_writing;
 
-    /** Decomposed encoding flags (e.g. `"enc:enc2""`). */
-    /*
-     * enc  enc2 read action                      write action
-     * NULL NULL force_encoding(default_external) write the byte sequence of str
-     * e1   NULL force_encoding(e1)               convert str.encoding to e1
-     * e1   e2   convert from e2 to e1            convert str.encoding to e2
-     */
-    struct rb_io_enc_t {
-        /** Internal encoding. */
-        rb_encoding *enc;
-
-        /** External encoding. */
-        rb_encoding *enc2;
-
-        /**
-         * Flags.
-         *
-         * @see enum ::ruby_econv_flag_type
-         */
-        int ecflags;
-
-        /**
-         * Flags as Ruby hash.
-         *
-         * @internal
-         *
-         * This is set.  But used from nowhere maybe?
-         */
-        VALUE ecopts;
-    } encs; /**< Decomposed encoding flags. */
+    struct rb_io_enc_t encs; /**< Decomposed encoding flags. */
 
     /** Encoding converter used when reading from this IO. */
     rb_econv_t *readconv;
@@ -212,6 +222,11 @@ typedef struct rb_io_t {
      * This of course doesn't help inter-process IO interleaves, though.
      */
     VALUE write_lock;
+
+    /**
+     * The timeout associated with this IO when performing blocking operations.
+     */
+    VALUE timeout;
 } rb_io_t;
 
 /** @alias{rb_io_enc_t} */
@@ -652,10 +667,23 @@ VALUE rb_io_get_write_io(VALUE io);
 VALUE rb_io_set_write_io(VALUE io, VALUE w);
 
 /**
- * Sets an IO to a "nonblock mode".  This amends the way an IO operates so that
- * instead of waiting for rooms for  read/write, it returns errors.  In case of
- * multiplexed IO  situations it can be  vital for IO operations  not to block.
- * This is the key API to achieve that property.
+ * Instructs the OS to put its internal file structure into "nonblocking mode".
+ * This is  an in-Kernel concept.   Reading from/writing  to that file  using C
+ * function calls would return  -1 with errno set.  However when  it comes to a
+ * ruby program,  we hide that error  behind our `IO#read` method.   Ruby level
+ * `IO#read` blocks  regardless of this flag.   If you want to  avoid blocking,
+ * you should consider using methods like `IO#readpartial`.
+ *
+ * ```ruby
+ * require 'io/nonblock'
+ * STDIN.nonblock = true
+ * STDIN.gets # blocks.
+ * ```
+ *
+ * As of  writing there is  a room  of this API  in Fiber schedulers.   A Fiber
+ * scheduler could be written in a  way its behaviour depends on this property.
+ * You  need an  in-depth  understanding  of how  schedulers  work to  properly
+ * leverage this, though.
  *
  * @note  Note   however  that   nonblocking-ness  propagates   across  process
  *        boundaries.  You must  really carefully watch your  step when turning
@@ -830,13 +858,37 @@ int rb_io_wait_writable(int fd);
 int rb_wait_for_single_fd(int fd, int events, struct timeval *tv);
 
 /**
+ * Get the timeout associated with the specified io object.
+ *
+ * @param[in]  io                   An IO object.
+ * @retval     RUBY_Qnil            There is no associated timeout.
+ * @retval     Otherwise            The timeout value.
+ */
+VALUE rb_io_timeout(VALUE io);
+
+/**
+ * Set the timeout associated with the specified io object. This timeout is
+ * used as a best effort timeout to prevent operations from blocking forever.
+ *
+ * @param[in]  io                   An IO object.
+ * @param[in]  timeout              A timeout value. Must respond to #to_f.
+ * @
+ */
+VALUE rb_io_set_timeout(VALUE io, VALUE timeout);
+
+/**
  * Blocks until  the passed IO  is ready for  the passed events.   The "events"
  * here is  a Ruby level  integer, which is  an OR-ed value  of `IO::READABLE`,
  * `IO::WRITable`, and `IO::PRIORITY`.
  *
+ * If timeout is `Qnil`, it will use the default timeout as given by
+ * `rb_io_timeout(io)`.
+ *
  * @param[in]  io                   An IO object to wait.
  * @param[in]  events               See above.
  * @param[in]  timeout              Time, or numeric seconds since UNIX epoch.
+ *                                  If Qnil, use the default timeout. If Qfalse
+ *                                  or Qundef, wait forever.
  * @exception  rb_eIOError          `io` is not open.
  * @exception  rb_eRangeError       `timeout` is out of range.
  * @exception  rb_eSystemCallError  `select(2)` failed for some reason.
@@ -888,13 +940,8 @@ VALUE rb_io_maybe_wait(int error, VALUE io, VALUE events, VALUE timeout);
  * @exception  rb_eIOError          `io` is not open.
  * @exception  rb_eRangeError       `timeout` is out of range.
  * @exception  rb_eSystemCallError  `select(2)` failed for some reason.
- * @exception  rb_eTypeError        Operation timed out.
- * @return     Always returns ::RUBY_IO_READABLE.
- *
- * @internal
- *
- * Because rb_io_maybe_wait()  returns ::RUBY_Qfalse on timeout,  this function
- * fails to convert that value to `int`, and raises ::rb_eTypeError.
+ * @retval     0                    Operation timed out.
+ * @retval     Otherwise            Always returns ::RUBY_IO_READABLE.
  */
 int rb_io_maybe_wait_readable(int error, VALUE io, VALUE timeout);
 
@@ -909,13 +956,8 @@ int rb_io_maybe_wait_readable(int error, VALUE io, VALUE timeout);
  * @exception  rb_eIOError          `io` is not open.
  * @exception  rb_eRangeError       `timeout` is out of range.
  * @exception  rb_eSystemCallError  `select(2)` failed for some reason.
- * @exception  rb_eTypeError        Operation timed out.
- * @return     Always returns ::RUBY_IO_WRITABLE.
- *
- * @internal
- *
- * Because rb_io_maybe_wait()  returns ::RUBY_Qfalse on timeout,  this function
- * fails to convert that value to `int`, and raises ::rb_eTypeError.
+ * @retval     0                    Operation timed out.
+ * @retval     Otherwise            Always returns ::RUBY_IO_WRITABLE.
  */
 int rb_io_maybe_wait_writable(int error, VALUE io, VALUE timeout);
 
diff --git a/include/ruby/io/buffer.h b/include/ruby/io/buffer.h
index 907fec20bb..e4b855d8e7 100644
--- a/include/ruby/io/buffer.h
+++ b/include/ruby/io/buffer.h
@@ -1,5 +1,5 @@
-#ifndef RUBY_IO_BUFFER_T
-#define RUBY_IO_BUFFER_T 1
+#ifndef RUBY_IO_BUFFER_H
+#define RUBY_IO_BUFFER_H
 /**
  * @file
  * @author     Samuel Williams
@@ -21,6 +21,8 @@ RBIMPL_SYMBOL_EXPORT_BEGIN()
 // WARNING: This entire interface is experimental and may change in the future!
 #define RB_IO_BUFFER_EXPERIMENTAL 1
 
+#define RUBY_IO_BUFFER_VERSION 2
+
 RUBY_EXTERN VALUE rb_cIOBuffer;
 RUBY_EXTERN size_t RUBY_IO_BUFFER_PAGE_SIZE;
 RUBY_EXTERN size_t RUBY_IO_BUFFER_DEFAULT_SIZE;
@@ -35,6 +37,9 @@ enum rb_io_buffer_flags {
     // A non-private mapping is marked as external.
     RB_IO_BUFFER_MAPPED = 4,
 
+    // A mapped buffer that is also shared.
+    RB_IO_BUFFER_SHARED = 8,
+
     // The buffer is locked and cannot be resized.
     // More specifically, it means we can't change the base address or size.
     // A buffer is typically locked before a system call that uses the data.
@@ -51,21 +56,17 @@ enum rb_io_buffer_endian {
     RB_IO_BUFFER_LITTLE_ENDIAN = 4,
     RB_IO_BUFFER_BIG_ENDIAN = 8,
 
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
-    RB_IO_BUFFER_HOST_ENDIAN = RB_IO_BUFFER_LITTLE_ENDIAN,
-#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+#if defined(WORDS_BIGENDIAN)
     RB_IO_BUFFER_HOST_ENDIAN = RB_IO_BUFFER_BIG_ENDIAN,
-#elif REG_DWORD == REG_DWORD_LITTLE_ENDIAN
+#else
     RB_IO_BUFFER_HOST_ENDIAN = RB_IO_BUFFER_LITTLE_ENDIAN,
-#elif REG_DWORD == REG_DWORD_BIG_ENDIAN
-    RB_IO_BUFFER_HOST_ENDIAN = RB_IO_BUFFER_BIG_ENDIAN,
 #endif
 
     RB_IO_BUFFER_NETWORK_ENDIAN = RB_IO_BUFFER_BIG_ENDIAN
 };
 
 VALUE rb_io_buffer_new(void *base, size_t size, enum rb_io_buffer_flags flags);
-VALUE rb_io_buffer_map(VALUE io, size_t size, off_t offset, enum rb_io_buffer_flags flags);
+VALUE rb_io_buffer_map(VALUE io, size_t size, rb_off_t offset, enum rb_io_buffer_flags flags);
 
 VALUE rb_io_buffer_lock(VALUE self);
 VALUE rb_io_buffer_unlock(VALUE self);
@@ -81,11 +82,11 @@ void rb_io_buffer_resize(VALUE self, size_t size);
 void rb_io_buffer_clear(VALUE self, uint8_t value, size_t offset, size_t length);
 
 // The length is the minimum required length.
-VALUE rb_io_buffer_read(VALUE self, VALUE io, size_t length);
-VALUE rb_io_buffer_pread(VALUE self, VALUE io, size_t length, off_t offset);
-VALUE rb_io_buffer_write(VALUE self, VALUE io, size_t length);
-VALUE rb_io_buffer_pwrite(VALUE self, VALUE io, size_t length, off_t offset);
+VALUE rb_io_buffer_read(VALUE self, VALUE io, size_t length, size_t offset);
+VALUE rb_io_buffer_pread(VALUE self, VALUE io, rb_off_t from, size_t length, size_t offset);
+VALUE rb_io_buffer_write(VALUE self, VALUE io, size_t length, size_t offset);
+VALUE rb_io_buffer_pwrite(VALUE self, VALUE io, rb_off_t from, size_t length, size_t offset);
 
 RBIMPL_SYMBOL_EXPORT_END()
 
-#endif  /* RUBY_IO_BUFFER_T */
+#endif  /* RUBY_IO_BUFFER_H */
diff --git a/include/ruby/memory_view.h b/include/ruby/memory_view.h
index 83931038a0..1ddca2d46f 100644
--- a/include/ruby/memory_view.h
+++ b/include/ruby/memory_view.h
@@ -16,7 +16,7 @@
 # include <stddef.h>                       /* size_t */
 #endif
 
-#if HAVE_SYS_TYPES_H
+#ifdef HAVE_SYS_TYPES_H
 # include <sys/types.h>                    /* ssize_t */
 #endif
 
diff --git a/include/ruby/onigmo.h b/include/ruby/onigmo.h
index a7ef59c7c8..8d7c601703 100644
--- a/include/ruby/onigmo.h
+++ b/include/ruby/onigmo.h
@@ -356,9 +356,9 @@ int onigenc_ascii_only_case_map(OnigCaseFoldType* flagP, const OnigUChar** pp, c
 #define ONIGENC_PRECISE_MBC_ENC_LEN(enc,p,e)   (enc)->precise_mbc_enc_len(p,e,enc)
 
 ONIG_EXTERN
-int onigenc_mbclen_approximate(const OnigUChar* p,const OnigUChar* e, const struct OnigEncodingTypeST* enc);
+int onigenc_mbclen(const OnigUChar* p,const OnigUChar* e, const struct OnigEncodingTypeST* enc);
 
-#define ONIGENC_MBC_ENC_LEN(enc,p,e)           onigenc_mbclen_approximate(p,e,enc)
+#define ONIGENC_MBC_ENC_LEN(enc,p,e)           onigenc_mbclen(p,e,enc)
 #define ONIGENC_MBC_MAXLEN(enc)               ((enc)->max_enc_len)
 #define ONIGENC_MBC_MAXLEN_DIST(enc)           ONIGENC_MBC_MAXLEN(enc)
 #define ONIGENC_MBC_MINLEN(enc)               ((enc)->min_enc_len)
@@ -744,6 +744,8 @@ typedef struct {
 typedef struct {
   int lower;
   int upper;
+  long base_num;
+  long inner_num;
 } OnigRepeatRange;
 
 typedef void (*OnigWarnFunc)(const char* s);
@@ -852,6 +854,8 @@ OnigPosition onig_search_gpos(OnigRegex, const OnigUChar* str, const OnigUChar*
 ONIG_EXTERN
 OnigPosition onig_match(OnigRegex, const OnigUChar* str, const OnigUChar* end, const OnigUChar* at, OnigRegion* region, OnigOptionType option);
 ONIG_EXTERN
+int onig_check_linear_time(OnigRegex reg);
+ONIG_EXTERN
 OnigRegion* onig_region_new(void);
 ONIG_EXTERN
 void onig_region_init(OnigRegion* region);
diff --git a/include/ruby/random.h b/include/ruby/random.h
index 657b37f034..39bdb6f3e3 100644
--- a/include/ruby/random.h
+++ b/include/ruby/random.h
@@ -16,6 +16,26 @@
 
 #include "ruby/ruby.h"
 
+/*
+ * version
+ * 0: before versioning; deprecated
+ * 1: added version, flags and init_32bit function
+ */
+#define RUBY_RANDOM_INTERFACE_VERSION_MAJOR 1
+#define RUBY_RANDOM_INTERFACE_VERSION_MINOR 0
+
+#define RUBY_RANDOM_PASTE_VERSION_SUFFIX(x, y, z) x##_##y##_##z
+#define RUBY_RANDOM_WITH_VERSION_SUFFIX(name, major, minor) \
+    RUBY_RANDOM_PASTE_VERSION_SUFFIX(name, major, minor)
+#define rb_random_data_type \
+    RUBY_RANDOM_WITH_VERSION_SUFFIX(rb_random_data_type, \
+                                    RUBY_RANDOM_INTERFACE_VERSION_MAJOR, \
+                                    RUBY_RANDOM_INTERFACE_VERSION_MINOR)
+#define RUBY_RANDOM_INTERFACE_VERSION_INITIALIZER \
+    {RUBY_RANDOM_INTERFACE_VERSION_MAJOR, RUBY_RANDOM_INTERFACE_VERSION_MINOR}
+#define RUBY_RANDOM_INTERFACE_VERSION_MAJOR_MAX 0xff
+#define RUBY_RANDOM_INTERFACE_VERSION_MINOR_MAX 0xff
+
 RBIMPL_SYMBOL_EXPORT_BEGIN()
 
 /**
@@ -48,6 +68,17 @@ typedef void rb_random_init_func(rb_random_t *rng, const uint32_t *buf, size_t l
 
 RBIMPL_ATTR_NONNULL(())
 /**
+ * This is the type of functions called when your random object is initialised.
+ * Passed data is the seed integer.
+ *
+ * @param[out]  rng  Your random struct to fill in.
+ * @param[in]   data Seed, single word.
+ * @post        `rng` is initialised using the passed seeds.
+ */
+typedef void rb_random_init_int32_func(rb_random_t *rng, uint32_t data);
+
+RBIMPL_ATTR_NONNULL(())
+/**
  * This is the type of functions  called from your object's `#rand` method.
  *
  * @param[out]  rng  Your random struct to extract an integer from.
@@ -84,9 +115,24 @@ typedef struct {
     /** Number of bits of seed numbers. */
     size_t default_seed_bits;
 
-    /** Initialiser function. */
+    /**
+     * Major/minor versions of this interface
+     */
+    struct {
+        uint8_t major, minor;
+    } version;
+
+    /**
+     * Reserved flags
+     */
+    uint16_t flags;
+
+    /** Function to initialize from uint32_t array. */
     rb_random_init_func *init;
 
+    /** Function to initialize from single uint32_t. */
+    rb_random_init_int32_func *init_int32;
+
     /** Function to obtain a random integer. */
     rb_random_get_int32_func *get_int32;
 
@@ -130,11 +176,12 @@ typedef struct {
 } rb_random_interface_t;
 
 /**
- * This utility macro defines  3 functions named prefix_init, prefix_get_int32,
- * prefix_get_bytes.
+ * This utility macro defines 4 functions named prefix_init, prefix_init_int32,
+ * prefix_get_int32, prefix_get_bytes.
  */
 #define RB_RANDOM_INTERFACE_DECLARE(prefix) \
     static void prefix##_init(rb_random_t *, const uint32_t *, size_t); \
+    static void prefix##_init_int32(rb_random_t *, uint32_t); \
     static unsigned int prefix##_get_int32(rb_random_t *); \
     static void prefix##_get_bytes(rb_random_t *, void *, size_t)
 
@@ -161,7 +208,9 @@ typedef struct {
  * ```
  */
 #define RB_RANDOM_INTERFACE_DEFINE(prefix) \
+    RUBY_RANDOM_INTERFACE_VERSION_INITIALIZER, 0, \
     prefix##_init, \
+    prefix##_init_int32, \
     prefix##_get_int32, \
     prefix##_get_bytes
 
@@ -173,6 +222,12 @@ typedef struct {
     RB_RANDOM_INTERFACE_DEFINE(prefix), \
     prefix##_get_real
 
+#define RB_RANDOM_DEFINE_INIT_INT32_FUNC(prefix) \
+    static void prefix##_init_int32(rb_random_t *rnd, uint32_t data) \
+    { \
+        prefix##_init(rnd, &data, 1); \
+    }
+
 #if defined _WIN32 && !defined __CYGWIN__
 typedef rb_data_type_t rb_random_data_type_t;
 # define RB_RANDOM_PARENT 0
@@ -189,7 +244,7 @@ typedef const rb_data_type_t rb_random_data_type_t;
  *     0, RB_RANDOM_INTERFACE_DEFINE(your),
  * };
  *
- * static inline constexpr your_prng = {
+ * static inline constexpr rb_random_data_type_t your_prng_type = {
  *     "your PRNG",
  *     { rb_random_mark, },
  *     RB_RANDOM_PARENT,                 // <<-- HERE
diff --git a/include/ruby/ruby.h b/include/ruby/ruby.h
index 108127a93c..444940ca3a 100644
--- a/include/ruby/ruby.h
+++ b/include/ruby/ruby.h
@@ -108,7 +108,7 @@ VALUE rb_get_path_no_checksafe(VALUE);
 # define rb_varargs_argc_check_runtime(argc, vargc) \
     (((argc) <= (vargc)) ? (argc) : \
      (rb_fatal("argc(%d) exceeds actual arguments(%d)", \
-	       argc, vargc), 0))
+               argc, vargc), 0))
 # define rb_varargs_argc_valid_p(argc, vargc) \
     ((argc) == 0 ? (vargc) <= 1 : /* [ruby-core:85266] [Bug #14425] */ \
      (argc) == (vargc))
@@ -117,16 +117,16 @@ VALUE rb_get_path_no_checksafe(VALUE);
 ERRORFUNC((" argument length doesn't match"), int rb_varargs_bad_length(int,int));
 #   else
 #     define rb_varargs_bad_length(argc, vargc) \
-	((argc)/rb_varargs_argc_valid_p(argc, vargc))
+        ((argc)/rb_varargs_argc_valid_p(argc, vargc))
 #   endif
 #   define rb_varargs_argc_check(argc, vargc) \
     __builtin_choose_expr(__builtin_constant_p(argc), \
-	(rb_varargs_argc_valid_p(argc, vargc) ? (argc) : \
-	 rb_varargs_bad_length(argc, vargc)), \
-	rb_varargs_argc_check_runtime(argc, vargc))
+        (rb_varargs_argc_valid_p(argc, vargc) ? (argc) : \
+         rb_varargs_bad_length(argc, vargc)), \
+        rb_varargs_argc_check_runtime(argc, vargc))
 # else
 #   define rb_varargs_argc_check(argc, vargc) \
-	rb_varargs_argc_check_runtime(argc, vargc)
+        rb_varargs_argc_check_runtime(argc, vargc)
 # endif
 #endif
 /** @endcond */
@@ -277,24 +277,24 @@ int ruby_vsnprintf(char *str, size_t n, char const *fmt, va_list ap);
 #elif defined(__GNUC__) && defined(HAVE_VA_ARGS_MACRO) && defined(__OPTIMIZE__)
 # define rb_yield_values(argc, ...) \
 __extension__({ \
-	const int rb_yield_values_argc = (argc); \
-	const VALUE rb_yield_values_args[] = {__VA_ARGS__}; \
-	const int rb_yield_values_nargs = \
-	    (int)(sizeof(rb_yield_values_args) / sizeof(VALUE)); \
-	rb_yield_values2( \
-	    rb_varargs_argc_check(rb_yield_values_argc, rb_yield_values_nargs), \
-	    rb_yield_values_nargs ? rb_yield_values_args : NULL); \
+        const int rb_yield_values_argc = (argc); \
+        const VALUE rb_yield_values_args[] = {__VA_ARGS__}; \
+        const int rb_yield_values_nargs = \
+            (int)(sizeof(rb_yield_values_args) / sizeof(VALUE)); \
+        rb_yield_values2( \
+            rb_varargs_argc_check(rb_yield_values_argc, rb_yield_values_nargs), \
+            rb_yield_values_nargs ? rb_yield_values_args : NULL); \
     })
 
 # define rb_funcall(recv, mid, argc, ...) \
 __extension__({ \
-	const int rb_funcall_argc = (argc); \
-	const VALUE rb_funcall_args[] = {__VA_ARGS__}; \
-	const int rb_funcall_nargs = \
-	    (int)(sizeof(rb_funcall_args) / sizeof(VALUE)); \
+        const int rb_funcall_argc = (argc); \
+        const VALUE rb_funcall_args[] = {__VA_ARGS__}; \
+        const int rb_funcall_nargs = \
+            (int)(sizeof(rb_funcall_args) / sizeof(VALUE)); \
         rb_funcallv(recv, mid, \
-	    rb_varargs_argc_check(rb_funcall_argc, rb_funcall_nargs), \
-	    rb_funcall_nargs ? rb_funcall_args : NULL); \
+            rb_varargs_argc_check(rb_funcall_argc, rb_funcall_nargs), \
+            rb_funcall_nargs ? rb_funcall_args : NULL); \
     })
 #endif
 /** @endcond */
diff --git a/include/ruby/st.h b/include/ruby/st.h
index 1e4bb80686..f35ab43603 100644
--- a/include/ruby/st.h
+++ b/include/ruby/st.h
@@ -98,6 +98,8 @@ struct st_table {
 
 enum st_retval {ST_CONTINUE, ST_STOP, ST_DELETE, ST_CHECK, ST_REPLACE};
 
+size_t rb_st_table_size(const struct st_table *tbl);
+#define st_table_size rb_st_table_size
 st_table *rb_st_init_table(const struct st_hash_type *);
 #define st_init_table rb_st_init_table
 st_table *rb_st_init_table_with_size(const struct st_hash_type *, st_index_t);
diff --git a/include/ruby/thread.h b/include/ruby/thread.h
index 18c792b386..0b5b1ca0f3 100644
--- a/include/ruby/thread.h
+++ b/include/ruby/thread.h
@@ -128,7 +128,7 @@ RBIMPL_ATTR_NONNULL((1))
  *                 your code to see if it is actually worth releasing the GVL.
  */
 void *rb_thread_call_without_gvl(void *(*func)(void *), void *data1,
-				 rb_unblock_function_t *ubf, void *data2);
+                                 rb_unblock_function_t *ubf, void *data2);
 
 RBIMPL_ATTR_NONNULL((1))
 /**
@@ -152,7 +152,7 @@ RBIMPL_ATTR_NONNULL((1))
  * @return         What `func` returned, or 0 in case `func` did not return.
  */
 void *rb_thread_call_without_gvl2(void *(*func)(void *), void *data1,
-				  rb_unblock_function_t *ubf, void *data2);
+                                  rb_unblock_function_t *ubf, void *data2);
 
 /*
  * XXX: unstable/unapproved - out-of-tree code should NOT not depend
@@ -190,6 +190,46 @@ void *rb_nogvl(void *(*func)(void *), void *data1,
  */
 #define RUBY_CALL_WO_GVL_FLAG_SKIP_CHECK_INTS_
 
+#define RUBY_INTERNAL_THREAD_EVENT_STARTED    1 << 0 /** thread started */
+#define RUBY_INTERNAL_THREAD_EVENT_READY      1 << 1 /** acquiring GVL */
+#define RUBY_INTERNAL_THREAD_EVENT_RESUMED    1 << 2 /** acquired GVL */
+#define RUBY_INTERNAL_THREAD_EVENT_SUSPENDED  1 << 3 /** released GVL */
+#define RUBY_INTERNAL_THREAD_EVENT_EXITED     1 << 4 /** thread terminated */
+#define RUBY_INTERNAL_THREAD_EVENT_MASK       0xff /** All Thread events */
+
+typedef void rb_internal_thread_event_data_t; // for future extension.
+
+typedef void (*rb_internal_thread_event_callback)(rb_event_flag_t event,
+              const rb_internal_thread_event_data_t *event_data,
+              void *user_data);
+typedef struct rb_internal_thread_event_hook rb_internal_thread_event_hook_t;
+
+/**
+ * Registers a thread event hook function.
+ *
+ * @param[in]  func    A callback.
+ * @param[in]  events  A set of events that `func` should run.
+ * @param[in]  data    Passed as-is to `func`.
+ * @return     An opaque pointer to the hook, to unregister it later.
+ * @note       This functionality is a noop on Windows.
+ * @warning    This function MUST not be called from a thread event callback.
+ */
+rb_internal_thread_event_hook_t *rb_internal_thread_add_event_hook(
+        rb_internal_thread_event_callback func, rb_event_flag_t events,
+        void *data);
+
+
+/**
+ * Unregister the passed hook.
+ *
+ * @param[in]  hook.  The hook to unregister.
+ * @return     Wether the hook was found and unregistered.
+ * @note       This functionality is a noop on Windows.
+ * @warning    This function MUST not be called from a thread event callback.
+*/
+bool rb_internal_thread_remove_event_hook(
+        rb_internal_thread_event_hook_t * hook);
+
 RBIMPL_SYMBOL_EXPORT_END()
 
 #endif /* RUBY_THREAD_H */
diff --git a/include/ruby/util.h b/include/ruby/util.h
index b2bc1a09f6..e8727a3200 100644
--- a/include/ruby/util.h
+++ b/include/ruby/util.h
@@ -19,7 +19,7 @@
 # include <stddef.h>                       /* size_t */
 #endif
 
-#if HAVE_SYS_TYPES_H
+#ifdef HAVE_SYS_TYPES_H
 # include <sys/types.h>                    /* ssize_t */
 #endif
 
@@ -124,7 +124,7 @@ unsigned long ruby_scan_hex(const char *str, size_t len, size_t *ret);
 # define ruby_qsort qsort_r
 #else
 void ruby_qsort(void *, const size_t, const size_t,
-		int (*)(const void *, const void *, void *), void *);
+                int (*)(const void *, const void *, void *), void *);
 #endif
 
 RBIMPL_ATTR_NONNULL((1))
diff --git a/include/ruby/version.h b/include/ruby/version.h
index f10b58f9c7..18b3abc8d7 100644
--- a/include/ruby/version.h
+++ b/include/ruby/version.h
@@ -137,7 +137,8 @@ RUBY_EXTERN const int  ruby_patchlevel;
 
 /**
  * This is what `ruby -v` prints to the standard error.  Something like:
- * `"ruby 2.5.9p229 (2021-04-05 revision 67829) [x86_64-linux]"`
+ * `"ruby 2.5.9p229 (2021-04-05 revision 67829) [x86_64-linux]"`. This doesn't
+ * include runtime options like a JIT being enabled.
  */
 RUBY_EXTERN const char ruby_description[];
 
diff --git a/include/ruby/win32.h b/include/ruby/win32.h
index a3f466d627..18de3a17d8 100644
--- a/include/ruby/win32.h
+++ b/include/ruby/win32.h
@@ -19,11 +19,6 @@ RUBY_SYMBOL_EXPORT_BEGIN
  */
 
 /*
- * Definitions for NT port of Perl
- */
-
-
-/*
  * Ok now we can include the normal include files.
  */
 
@@ -130,8 +125,15 @@ typedef unsigned int uintptr_t;
 #define O_SHARE_DELETE 0x20000000 /* for rb_w32_open(), rb_w32_wopen() */
 
 typedef int clockid_t;
+#if defined(__MINGW32__)
+#undef CLOCK_PROCESS_CPUTIME_ID
+#undef CLOCK_THREAD_CPUTIME_ID
+#undef CLOCK_REALTIME_COARSE
+#endif
+#if defined(HAVE_CLOCK_GETTIME) && !defined(CLOCK_REALTIME)
 #define CLOCK_REALTIME  0
 #define CLOCK_MONOTONIC 1
+#endif
 
 #undef utime
 #undef lseek
@@ -195,7 +197,6 @@ struct stati128 {
   long st_ctimensec;
 };
 
-#define off_t __int64
 #define stat stati128
 #undef SIZEOF_STRUCT_STAT_ST_INO
 #define SIZEOF_STRUCT_STAT_ST_INO sizeof(unsigned __int64)
@@ -303,7 +304,6 @@ extern DWORD  rb_w32_osver(void);
 extern int rb_w32_uchown(const char *, int, int);
 extern int rb_w32_ulink(const char *, const char *);
 extern ssize_t rb_w32_ureadlink(const char *, char *, size_t);
-extern ssize_t rb_w32_wreadlink(const WCHAR *, WCHAR *, size_t);
 extern int rb_w32_usymlink(const char *src, const char *link);
 extern int gettimeofday(struct timeval *, struct timezone *);
 extern int clock_gettime(clockid_t, struct timespec *);
@@ -394,6 +394,7 @@ scalb(double a, long b)
 #endif
 
 #define S_IFLNK 0xa000
+#define S_IFSOCK 0xc000
 
 /*
  * define this so we can do inplace editing
@@ -401,9 +402,9 @@ scalb(double a, long b)
 
 #define SUFFIX
 
-extern int rb_w32_ftruncate(int fd, off_t length);
-extern int rb_w32_truncate(const char *path, off_t length);
-extern int rb_w32_utruncate(const char *path, off_t length);
+extern int rb_w32_ftruncate(int fd, rb_off_t length);
+extern int rb_w32_truncate(const char *path, rb_off_t length);
+extern int rb_w32_utruncate(const char *path, rb_off_t length);
 
 #undef HAVE_FTRUNCATE
 #define HAVE_FTRUNCATE 1
@@ -702,10 +703,10 @@ extern char *rb_w32_strerror(int);
 #endif
 
 struct tms {
-	long	tms_utime;
-	long	tms_stime;
-	long	tms_cutime;
-	long	tms_cstime;
+        long	tms_utime;
+        long	tms_stime;
+        long	tms_cutime;
+        long	tms_cstime;
 };
 
 int rb_w32_times(struct tms *);
@@ -722,7 +723,7 @@ int  rb_w32_fclose(FILE*);
 int  rb_w32_pipe(int[2]);
 ssize_t rb_w32_read(int, void *, size_t);
 ssize_t rb_w32_write(int, const void *, size_t);
-off_t  rb_w32_lseek(int, off_t, int);
+rb_off_t  rb_w32_lseek(int, rb_off_t, int);
 int  rb_w32_uutime(const char *, const struct utimbuf *);
 int  rb_w32_uutimes(const char *, const struct timeval *);
 int  rb_w32_uutimensat(int /* must be AT_FDCWD */, const char *, const struct timespec *, int /* must be 0 */);
@@ -815,7 +816,7 @@ double rb_w32_pow(double x, double y);
 #define MAP_ANON	0x1000
 #define MAP_ANONYMOUS	MAP_ANON
 
-extern void *rb_w32_mmap(void *, size_t, int, int, int, off_t);
+extern void *rb_w32_mmap(void *, size_t, int, int, int, rb_off_t);
 extern int rb_w32_munmap(void *, size_t);
 extern int rb_w32_mprotect(void *, size_t, int);
 
diff --git a/inits.c b/inits.c
index 8c230c6df0..e809b56cc9 100644
--- a/inits.c
+++ b/inits.c
@@ -20,6 +20,7 @@ static void Init_builtin_prelude(void);
 void
 rb_call_inits(void)
 {
+    CALL(default_shapes);
     CALL(Thread_Mutex);
 #if USE_TRANSIENT_HEAP
     CALL(TransientHeap);
@@ -77,6 +78,7 @@ rb_call_inits(void)
     CALL(vm_stack_canary);
     CALL(ast);
     CALL(gc_stress);
+    CALL(shape);
 
     // enable builtin loading
     CALL(builtin);
@@ -97,10 +99,16 @@ rb_call_builtin_inits(void)
     BUILTIN(warning);
     BUILTIN(array);
     BUILTIN(kernel);
+    BUILTIN(symbol);
     BUILTIN(timev);
+    BUILTIN(thread_sync);
     BUILTIN(yjit);
     BUILTIN(nilclass);
     BUILTIN(marshal);
+#if USE_MJIT
+    BUILTIN(mjit);
+    BUILTIN(mjit_c);
+#endif
     Init_builtin_prelude();
 }
 #undef CALL
diff --git a/insns.def b/insns.def
index b5dea9c10c..9f5ee7095a 100644
--- a/insns.def
+++ b/insns.def
@@ -109,14 +109,14 @@ getblockparam
     VM_ASSERT(VM_ENV_LOCAL_P(ep));
 
     if (!VM_ENV_FLAGS(ep, VM_FRAME_FLAG_MODIFIED_BLOCK_PARAM)) {
-	val = rb_vm_bh_to_procval(ec, VM_ENV_BLOCK_HANDLER(ep));
-	vm_env_write(ep, -(int)idx, val);
-	VM_ENV_FLAGS_SET(ep, VM_FRAME_FLAG_MODIFIED_BLOCK_PARAM);
+        val = rb_vm_bh_to_procval(ec, VM_ENV_BLOCK_HANDLER(ep));
+        vm_env_write(ep, -(int)idx, val);
+        VM_ENV_FLAGS_SET(ep, VM_FRAME_FLAG_MODIFIED_BLOCK_PARAM);
     }
     else {
-	val = *(ep - idx);
-	RB_DEBUG_COUNTER_INC(lvar_get);
-	(void)RB_DEBUG_COUNTER_INC_IF(lvar_get_dynamic, level > 0);
+        val = *(ep - idx);
+        RB_DEBUG_COUNTER_INC(lvar_get);
+        (void)RB_DEBUG_COUNTER_INC_IF(lvar_get_dynamic, level > 0);
     }
 }
 
@@ -150,35 +150,35 @@ getblockparamproxy
     VM_ASSERT(VM_ENV_LOCAL_P(ep));
 
     if (!VM_ENV_FLAGS(ep, VM_FRAME_FLAG_MODIFIED_BLOCK_PARAM)) {
-	VALUE block_handler = VM_ENV_BLOCK_HANDLER(ep);
-
-	if (block_handler) {
-	    switch (vm_block_handler_type(block_handler)) {
-	      case block_handler_type_iseq:
-	      case block_handler_type_ifunc:
-		val = rb_block_param_proxy;
-		break;
-	      case block_handler_type_symbol:
-		val = rb_sym_to_proc(VM_BH_TO_SYMBOL(block_handler));
-		goto INSN_LABEL(set);
-	      case block_handler_type_proc:
-		val = VM_BH_TO_PROC(block_handler);
-		goto INSN_LABEL(set);
-	      default:
-		VM_UNREACHABLE(getblockparamproxy);
-	    }
-	}
-	else {
-	    val = Qnil;
-	  INSN_LABEL(set):
-	    vm_env_write(ep, -(int)idx, val);
-	    VM_ENV_FLAGS_SET(ep, VM_FRAME_FLAG_MODIFIED_BLOCK_PARAM);
-	}
+        VALUE block_handler = VM_ENV_BLOCK_HANDLER(ep);
+
+        if (block_handler) {
+            switch (vm_block_handler_type(block_handler)) {
+              case block_handler_type_iseq:
+              case block_handler_type_ifunc:
+                val = rb_block_param_proxy;
+                break;
+              case block_handler_type_symbol:
+                val = rb_sym_to_proc(VM_BH_TO_SYMBOL(block_handler));
+                goto INSN_LABEL(set);
+              case block_handler_type_proc:
+                val = VM_BH_TO_PROC(block_handler);
+                goto INSN_LABEL(set);
+              default:
+                VM_UNREACHABLE(getblockparamproxy);
+            }
+        }
+        else {
+            val = Qnil;
+          INSN_LABEL(set):
+            vm_env_write(ep, -(int)idx, val);
+            VM_ENV_FLAGS_SET(ep, VM_FRAME_FLAG_MODIFIED_BLOCK_PARAM);
+        }
     }
     else {
-	val = *(ep - idx);
-	RB_DEBUG_COUNTER_INC(lvar_get);
-	(void)RB_DEBUG_COUNTER_INC_IF(lvar_get_dynamic, level > 0);
+        val = *(ep - idx);
+        RB_DEBUG_COUNTER_INC(lvar_get);
+        (void)RB_DEBUG_COUNTER_INC_IF(lvar_get_dynamic, level > 0);
     }
 }
 
@@ -253,6 +253,29 @@ setclassvariable
     vm_setclassvariable(GET_ISEQ(), GET_CFP(), id,  val, ic);
 }
 
+DEFINE_INSN
+opt_getconstant_path
+(IC ic)
+()
+(VALUE val)
+// attr bool leaf = false; /* may autoload or raise */
+{
+    const ID *segments = ic->segments;
+    struct iseq_inline_constant_cache_entry *ice = ic->entry;
+    if (ice && vm_ic_hit_p(ice, GET_EP())) {
+        val = ice->value;
+
+        VM_ASSERT(val == vm_get_ev_const_chain(ec, segments));
+    } else {
+        ruby_vm_constant_cache_misses++;
+        val = vm_get_ev_const_chain(ec, segments);
+        vm_ic_track_const_chain(GET_CFP(), ic, segments);
+        // Because leaf=false, we need to undo the PC increment to get the address to this instruction
+        // INSN_ATTR(width) == 2
+        vm_ic_update(GET_ISEQ(), ic, val, GET_EP(), GET_PC() - 2);
+    }
+}
+
 /* Get constant variable id. If klass is Qnil and allow_nil is Qtrue, constants
    are searched in the current scope. Otherwise, get constant under klass
    class or module.
@@ -597,6 +620,25 @@ swap
     /* none */
 }
 
+/* reverse stack top N order. */
+DEFINE_INSN
+opt_reverse
+(rb_num_t n)
+(...)
+(...)
+// attr rb_snum_t sp_inc = 0;
+{
+    rb_num_t i;
+    VALUE *sp = STACK_ADDR_FROM_TOP(n);
+
+    for (i=0; i<n/2; i++) {
+	VALUE v0 = sp[i];
+	VALUE v1 = TOPN(i);
+	sp[i] = v1;
+	TOPN(i) = v0;
+    }
+}
+
 /* for stack caching. */
 DEFINE_INSN_IF(STACK_CACHING)
 reput
@@ -655,7 +697,7 @@ defined
 {
     val = Qnil;
     if (vm_defined(ec, GET_CFP(), op_type, obj, v)) {
-      val = pushval;
+        val = pushval;
     }
 }
 
@@ -715,8 +757,8 @@ defineclass
 
     /* enter scope */
     vm_push_frame(ec, class_iseq, VM_FRAME_MAGIC_CLASS | VM_ENV_FLAG_LOCAL, klass,
-		  GET_BLOCK_HANDLER(),
-		  (VALUE)vm_cref_push(ec, klass, NULL, FALSE, FALSE),
+                  GET_BLOCK_HANDLER(),
+                  (VALUE)vm_cref_push(ec, klass, NULL, FALSE, FALSE),
                   ISEQ_BODY(class_iseq)->iseq_encoded, GET_SP(),
                   ISEQ_BODY(class_iseq)->local_table_size,
                   ISEQ_BODY(class_iseq)->stack_max);
@@ -920,19 +962,19 @@ leave
         const VALUE *const bp = vm_base_ptr(GET_CFP());
         if (GET_SP() != bp) {
             vm_stack_consistency_error(ec, GET_CFP(), bp);
-	}
+        }
     }
 
     if (vm_pop_frame(ec, GET_CFP(), GET_EP())) {
 #if OPT_CALL_THREADED_CODE
-	rb_ec_thread_ptr(ec)->retval = val;
-	return 0;
+        rb_ec_thread_ptr(ec)->retval = val;
+        return 0;
 #else
-	return val;
+        return val;
 #endif
     }
     else {
-	RESTORE_REGS();
+        RESTORE_REGS();
     }
 }
 
@@ -981,8 +1023,8 @@ branchif
 // attr bool leaf = leafness_of_check_ints; /* has rb_threadptr_execute_interrupts() */
 {
     if (RTEST(val)) {
-	RUBY_VM_CHECK_INTS(ec);
-	JUMP(dst);
+        RUBY_VM_CHECK_INTS(ec);
+        JUMP(dst);
     }
 }
 
@@ -996,8 +1038,8 @@ branchunless
 // attr bool leaf = leafness_of_check_ints; /* has rb_threadptr_execute_interrupts() */
 {
     if (!RTEST(val)) {
-	RUBY_VM_CHECK_INTS(ec);
-	JUMP(dst);
+        RUBY_VM_CHECK_INTS(ec);
+        JUMP(dst);
     }
 }
 
@@ -1011,8 +1053,8 @@ branchnil
 // attr bool leaf = leafness_of_check_ints; /* has rb_threadptr_execute_interrupts() */
 {
     if (NIL_P(val)) {
-	RUBY_VM_CHECK_INTS(ec);
-	JUMP(dst);
+        RUBY_VM_CHECK_INTS(ec);
+        JUMP(dst);
     }
 }
 
@@ -1020,46 +1062,6 @@ branchnil
 /* for optimize                                           */
 /**********************************************************/
 
-/* push inline-cached value and go to dst if it is valid */
-DEFINE_INSN
-opt_getinlinecache
-(OFFSET dst, IC ic)
-()
-(VALUE val)
-{
-    struct iseq_inline_constant_cache_entry *ice = ic->entry;
-
-    // If there isn't an entry, then we're going to walk through the ISEQ
-    // starting at this instruction until we get to the associated
-    // opt_setinlinecache and associate this inline cache with every getconstant
-    // listed in between. We're doing this here instead of when the instructions
-    // are first compiled because it's possible to turn off inline caches and we
-    // want this to work in either case.
-    if (!ice) {
-        vm_ic_compile(GET_CFP(), ic);
-    }
-
-    if (ice && vm_ic_hit_p(ice, GET_EP())) {
-        val = ice->value;
-        JUMP(dst);
-    }
-    else {
-        ruby_vm_constant_cache_misses++;
-        val = Qnil;
-    }
-}
-
-/* set inline cache */
-DEFINE_INSN
-opt_setinlinecache
-(IC ic)
-(VALUE val)
-(VALUE val)
-// attr bool leaf = false;
-{
-    vm_ic_update(GET_ISEQ(), ic, val, GET_EP());
-}
-
 /* run iseq only once */
 DEFINE_INSN
 once
@@ -1081,7 +1083,7 @@ opt_case_dispatch
     OFFSET dst = vm_case_dispatch(hash, else_offset, key);
 
     if (dst) {
-	JUMP(dst);
+        JUMP(dst);
     }
 }
 
@@ -1340,12 +1342,12 @@ opt_aset_with
     VALUE tmp = vm_opt_aset_with(recv, key, val);
 
     if (tmp != Qundef) {
-	val = tmp;
+        val = tmp;
     }
     else {
 #ifndef MJIT_HEADER
-	TOPN(0) = rb_str_resurrect(key);
-	PUSH(val);
+        TOPN(0) = rb_str_resurrect(key);
+        PUSH(val);
 #endif
         CALL_SIMPLE_METHOD();
     }
@@ -1364,7 +1366,7 @@ opt_aref_with
 
     if (val == Qundef) {
 #ifndef MJIT_HEADER
-	PUSH(rb_str_resurrect(key));
+        PUSH(rb_str_resurrect(key));
 #endif
         CALL_SIMPLE_METHOD();
     }
@@ -1467,9 +1469,9 @@ opt_call_c_function
     reg_cfp = (funcptr)(ec, reg_cfp);
 
     if (reg_cfp == 0) {
-	VALUE err = ec->errinfo;
-	ec->errinfo = Qnil;
-	THROW_EXCEPTION(err);
+        VALUE err = ec->errinfo;
+        ec->errinfo = Qnil;
+        THROW_EXCEPTION(err);
     }
 
     RESTORE_REGS();
diff --git a/internal.h b/internal.h
index 00a8295295..b63af50616 100644
--- a/internal.h
+++ b/internal.h
@@ -25,6 +25,9 @@
 /* Prevent compiler from reordering access */
 #define ACCESS_ONCE(type,x) (*((volatile type *)&(x)))
 
+#define UNDEF_P         RB_UNDEF_P
+#define NIL_OR_UNDEF_P  RB_NIL_OR_UNDEF_P
+
 #include "ruby/ruby.h"
 
 /* Following macros were formerly defined in this header but moved to somewhere
@@ -48,9 +51,6 @@
 #undef RHASH_TBL
 #undef RHASH_EMPTY_P
 
-/* internal/object.h */
-#undef ROBJECT_IV_INDEX_TBL
-
 /* internal/struct.h */
 #undef RSTRUCT_LEN
 #undef RSTRUCT_PTR
@@ -106,4 +106,8 @@ RUBY_SYMBOL_EXPORT_END
 #define RBOOL(v) ((v) ? Qtrue : Qfalse)
 #define RB_BIGNUM_TYPE_P(x) RB_TYPE_P((x), T_BIGNUM)
 
+#ifndef __MINGW32__
+#undef memcpy
+#define memcpy ruby_nonempty_memcpy
+#endif
 #endif /* RUBY_INTERNAL_H */
diff --git a/internal/array.h b/internal/array.h
index 60f66f31bf..a0d16dec3f 100644
--- a/internal/array.h
+++ b/internal/array.h
@@ -18,18 +18,24 @@
 # define ARRAY_DEBUG (0+RUBY_DEBUG)
 #endif
 
-#define RARRAY_PTR_IN_USE_FLAG FL_USER14
+#define RARRAY_SHARED_FLAG      ELTS_SHARED
+#define RARRAY_SHARED_ROOT_FLAG FL_USER12
+#define RARRAY_PTR_IN_USE_FLAG  FL_USER14
 
 /* array.c */
 VALUE rb_ary_last(int, const VALUE *, VALUE);
 void rb_ary_set_len(VALUE, long);
 void rb_ary_delete_same(VALUE, VALUE);
-VALUE rb_ary_tmp_new_fill(long capa);
+VALUE rb_ary_hidden_new_fill(long capa);
 VALUE rb_ary_at(VALUE, VALUE);
 size_t rb_ary_memsize(VALUE);
 VALUE rb_to_array_type(VALUE obj);
 VALUE rb_to_array(VALUE obj);
 void rb_ary_cancel_sharing(VALUE ary);
+size_t rb_ary_size_as_embedded(VALUE ary);
+void rb_ary_make_embedded(VALUE ary);
+bool rb_ary_embeddable_p(VALUE ary);
+VALUE rb_ary_diff(VALUE ary1, VALUE ary2);
 
 static inline VALUE rb_ary_entry_internal(VALUE ary, long offset);
 static inline bool ARY_PTR_USING_P(VALUE ary);
@@ -69,6 +75,50 @@ ARY_PTR_USING_P(VALUE ary)
     return FL_TEST_RAW(ary, RARRAY_PTR_IN_USE_FLAG);
 }
 
+RBIMPL_ATTR_MAYBE_UNUSED()
+static inline int
+ary_should_not_be_shared_and_embedded(VALUE ary)
+{
+    return !FL_ALL_RAW(ary, RARRAY_SHARED_FLAG|RARRAY_EMBED_FLAG);
+}
+
+static inline bool
+ARY_SHARED_P(VALUE ary)
+{
+    assert(RB_TYPE_P(ary, T_ARRAY));
+    assert(ary_should_not_be_shared_and_embedded(ary));
+    return FL_TEST_RAW(ary, RARRAY_SHARED_FLAG);
+}
+
+static inline bool
+ARY_EMBED_P(VALUE ary)
+{
+    assert(RB_TYPE_P(ary, T_ARRAY));
+    assert(ary_should_not_be_shared_and_embedded(ary));
+    return FL_TEST_RAW(ary, RARRAY_EMBED_FLAG);
+}
+
+static inline VALUE
+ARY_SHARED_ROOT(VALUE ary)
+{
+    assert(ARY_SHARED_P(ary));
+    return RARRAY(ary)->as.heap.aux.shared_root;
+}
+
+static inline bool
+ARY_SHARED_ROOT_P(VALUE ary)
+{
+    assert(RB_TYPE_P(ary, T_ARRAY));
+    return FL_TEST_RAW(ary, RARRAY_SHARED_ROOT_FLAG);
+}
+
+static inline long
+ARY_SHARED_ROOT_REFCNT(VALUE ary)
+{
+    assert(ARY_SHARED_ROOT_P(ary));
+    return RARRAY(ary)->as.heap.aux.capa;
+}
+
 static inline void
 RARY_TRANSIENT_SET(VALUE ary)
 {
diff --git a/internal/basic_operators.h b/internal/basic_operators.h
new file mode 100644
index 0000000000..2cd9f50073
--- /dev/null
+++ b/internal/basic_operators.h
@@ -0,0 +1,64 @@
+#ifndef INTERNAL_BOP_H                                /*-*-C-*-vi:se ft=c:*/
+#define INTERNAL_BOP_H
+
+#include "internal.h"
+#include "ruby/internal/dllexport.h"
+
+enum ruby_basic_operators {
+    BOP_PLUS,
+    BOP_MINUS,
+    BOP_MULT,
+    BOP_DIV,
+    BOP_MOD,
+    BOP_EQ,
+    BOP_EQQ,
+    BOP_LT,
+    BOP_LE,
+    BOP_LTLT,
+    BOP_AREF,
+    BOP_ASET,
+    BOP_LENGTH,
+    BOP_SIZE,
+    BOP_EMPTY_P,
+    BOP_NIL_P,
+    BOP_SUCC,
+    BOP_GT,
+    BOP_GE,
+    BOP_NOT,
+    BOP_NEQ,
+    BOP_MATCH,
+    BOP_FREEZE,
+    BOP_UMINUS,
+    BOP_MAX,
+    BOP_MIN,
+    BOP_CALL,
+    BOP_AND,
+    BOP_OR,
+    BOP_CMP,
+    BOP_DEFAULT,
+
+    BOP_LAST_
+};
+
+MJIT_SYMBOL_EXPORT_BEGIN
+RUBY_EXTERN short ruby_vm_redefined_flag[BOP_LAST_];
+MJIT_SYMBOL_EXPORT_END
+
+/* optimize insn */
+#define INTEGER_REDEFINED_OP_FLAG (1 << 0)
+#define FLOAT_REDEFINED_OP_FLAG  (1 << 1)
+#define STRING_REDEFINED_OP_FLAG (1 << 2)
+#define ARRAY_REDEFINED_OP_FLAG  (1 << 3)
+#define HASH_REDEFINED_OP_FLAG   (1 << 4)
+/* #define BIGNUM_REDEFINED_OP_FLAG (1 << 5) */
+#define SYMBOL_REDEFINED_OP_FLAG (1 << 6)
+#define TIME_REDEFINED_OP_FLAG   (1 << 7)
+#define REGEXP_REDEFINED_OP_FLAG (1 << 8)
+#define NIL_REDEFINED_OP_FLAG    (1 << 9)
+#define TRUE_REDEFINED_OP_FLAG   (1 << 10)
+#define FALSE_REDEFINED_OP_FLAG  (1 << 11)
+#define PROC_REDEFINED_OP_FLAG   (1 << 12)
+
+#define BASIC_OP_UNREDEFINED_P(op, klass) (LIKELY((ruby_vm_redefined_flag[(op)]&(klass)) == 0))
+
+#endif
diff --git a/internal/class.h b/internal/class.h
index be2f703fc8..63917e867f 100644
--- a/internal/class.h
+++ b/internal/class.h
@@ -14,6 +14,10 @@
 #include "ruby/internal/stdbool.h"     /* for bool */
 #include "ruby/intern.h"        /* for rb_alloc_func_t */
 #include "ruby/ruby.h"          /* for struct RBasic */
+#include "shape.h"
+#include "ruby_assert.h"
+#include "vm_core.h"
+#include "method.h"             /* for rb_cref_t */
 
 #ifdef RCLASS_SUPER
 # undef RCLASS_SUPER
@@ -25,24 +29,15 @@ struct rb_subclass_entry {
     struct rb_subclass_entry *prev;
 };
 
-struct rb_iv_index_tbl_entry {
-    uint32_t index;
-    rb_serial_t class_serial;
-    VALUE class_value;
-};
-
 struct rb_cvar_class_tbl_entry {
     uint32_t index;
     rb_serial_t global_cvar_state;
+    const rb_cref_t * cref;
     VALUE class_value;
 };
 
 struct rb_classext_struct {
-    struct st_table *iv_index_tbl; // ID -> struct rb_iv_index_tbl_entry
-    struct st_table *iv_tbl;
-#if SIZEOF_SERIAL_T == SIZEOF_VALUE /* otherwise m_tbl is in struct RClass */
-    struct rb_id_table *m_tbl;
-#endif
+    VALUE *iv_ptr;
     struct rb_id_table *const_tbl;
     struct rb_id_table *callable_m_tbl;
     struct rb_id_table *cc_tbl; /* ID -> [[ci, cc1], cc2, ...] */
@@ -57,63 +52,42 @@ struct rb_classext_struct {
      * included. Hopefully that makes sense.
      */
     struct rb_subclass_entry *module_subclass_entry;
-#if SIZEOF_SERIAL_T != SIZEOF_VALUE && !USE_RVARGC /* otherwise class_serial is in struct RClass */
-    rb_serial_t class_serial;
-#endif
     const VALUE origin_;
     const VALUE refined_class;
     rb_alloc_func_t allocator;
     const VALUE includer;
+    uint32_t max_iv_count;
+    uint32_t variation_count;
+#if !SHAPE_IN_BASIC_FLAGS
+    shape_id_t shape_id;
+#endif
 };
 
 struct RClass {
     struct RBasic basic;
     VALUE super;
-#if !USE_RVARGC
-    struct rb_classext_struct *ptr;
-#endif
-#if SIZEOF_SERIAL_T == SIZEOF_VALUE
-    /* Class serial is as wide as VALUE.  Place it here. */
-    rb_serial_t class_serial;
-#else
-    /* Class serial does not fit into struct RClass. Place m_tbl instead. */
     struct rb_id_table *m_tbl;
-# if USE_RVARGC
-    rb_serial_t *class_serial_ptr;
-# endif
+#if SIZE_POOL_COUNT == 1
+    struct rb_classext_struct *ptr;
 #endif
 };
 
 typedef struct rb_subclass_entry rb_subclass_entry_t;
 typedef struct rb_classext_struct rb_classext_t;
 
-#if USE_RVARGC
+#if RCLASS_EXT_EMBEDDED
 #  define RCLASS_EXT(c) ((rb_classext_t *)((char *)(c) + sizeof(struct RClass)))
 #else
 #  define RCLASS_EXT(c) (RCLASS(c)->ptr)
 #endif
-#define RCLASS_IV_TBL(c) (RCLASS_EXT(c)->iv_tbl)
 #define RCLASS_CONST_TBL(c) (RCLASS_EXT(c)->const_tbl)
-#if SIZEOF_SERIAL_T == SIZEOF_VALUE
-# define RCLASS_M_TBL(c) (RCLASS_EXT(c)->m_tbl)
-#else
-# define RCLASS_M_TBL(c) (RCLASS(c)->m_tbl)
-#endif
+#define RCLASS_M_TBL(c) (RCLASS(c)->m_tbl)
+#define RCLASS_IVPTR(c) (RCLASS_EXT(c)->iv_ptr)
 #define RCLASS_CALLABLE_M_TBL(c) (RCLASS_EXT(c)->callable_m_tbl)
 #define RCLASS_CC_TBL(c) (RCLASS_EXT(c)->cc_tbl)
 #define RCLASS_CVC_TBL(c) (RCLASS_EXT(c)->cvc_tbl)
-#define RCLASS_IV_INDEX_TBL(c) (RCLASS_EXT(c)->iv_index_tbl)
 #define RCLASS_ORIGIN(c) (RCLASS_EXT(c)->origin_)
 #define RCLASS_REFINED_CLASS(c) (RCLASS_EXT(c)->refined_class)
-#if SIZEOF_SERIAL_T == SIZEOF_VALUE
-# define RCLASS_SERIAL(c) (RCLASS(c)->class_serial)
-#else
-# if USE_RVARGC
-#  define RCLASS_SERIAL(c) (*RCLASS(c)->class_serial_ptr)
-# else
-#  define RCLASS_SERIAL(c) (RCLASS_EXT(c)->class_serial)
-# endif
-#endif
 #define RCLASS_INCLUDER(c) (RCLASS_EXT(c)->includer)
 #define RCLASS_SUBCLASS_ENTRY(c) (RCLASS_EXT(c)->subclass_entry)
 #define RCLASS_MODULE_SUBCLASS_ENTRY(c) (RCLASS_EXT(c)->module_subclass_entry)
@@ -122,10 +96,10 @@ typedef struct rb_classext_struct rb_classext_t;
 #define RCLASS_SUPERCLASS_DEPTH(c) (RCLASS_EXT(c)->superclass_depth)
 #define RCLASS_SUPERCLASSES(c) (RCLASS_EXT(c)->superclasses)
 
-#define RICLASS_IS_ORIGIN FL_USER5
-#define RCLASS_CLONED     FL_USER6
-#define RCLASS_SUPERCLASSES_INCLUDE_SELF FL_USER7
-#define RICLASS_ORIGIN_SHARED_MTBL FL_USER8
+#define RICLASS_IS_ORIGIN FL_USER0
+#define RCLASS_CLONED     FL_USER1
+#define RCLASS_SUPERCLASSES_INCLUDE_SELF FL_USER2
+#define RICLASS_ORIGIN_SHARED_MTBL FL_USER3
 
 /* class.c */
 void rb_class_subclass_add(VALUE super, VALUE klass);
@@ -145,10 +119,12 @@ void rb_class_foreach_subclass(VALUE klass, void (*f)(VALUE, VALUE), VALUE);
 void rb_class_detach_subclasses(VALUE);
 void rb_class_detach_module_subclasses(VALUE);
 void rb_class_remove_from_module_subclasses(VALUE);
+VALUE rb_define_class_id_under_no_pin(VALUE outer, ID id, VALUE super);
 VALUE rb_obj_methods(int argc, const VALUE *argv, VALUE obj);
 VALUE rb_obj_protected_methods(int argc, const VALUE *argv, VALUE obj);
 VALUE rb_obj_private_methods(int argc, const VALUE *argv, VALUE obj);
 VALUE rb_obj_public_methods(int argc, const VALUE *argv, VALUE obj);
+VALUE rb_class_undefined_instance_methods(VALUE mod);
 VALUE rb_special_singleton_class(VALUE);
 VALUE rb_singleton_class_clone_and_attach(VALUE obj, VALUE attach);
 VALUE rb_singleton_class_get(VALUE obj);
diff --git a/internal/cmdlineopt.h b/internal/cmdlineopt.h
index adc76fc2e4..bf52f1214b 100644
--- a/internal/cmdlineopt.h
+++ b/internal/cmdlineopt.h
@@ -26,9 +26,6 @@ typedef struct ruby_cmdline_options {
 #if USE_MJIT
     struct mjit_options mjit;
 #endif
-#if YJIT_SUPPORTED_P
-    struct rb_yjit_options yjit;
-#endif
 
     int sflag, xflag;
     unsigned int warning: 1;
@@ -39,6 +36,9 @@ typedef struct ruby_cmdline_options {
     unsigned int do_split: 1;
     unsigned int do_search: 1;
     unsigned int setids: 2;
+#if USE_YJIT
+    unsigned int yjit: 1;
+#endif
 } ruby_cmdline_options_t;
 
 struct ruby_opt_message {
diff --git a/internal/compar.h b/internal/compar.h
index 5e336adafa..9115e4bd63 100644
--- a/internal/compar.h
+++ b/internal/compar.h
@@ -8,38 +8,18 @@
  *             file COPYING are met.  Consult the file for details.
  * @brief      Internal header for Comparable.
  */
-#include "internal/vm.h"        /* for rb_method_basic_definition_p */
+#include "internal/basic_operators.h"
 
 #define STRING_P(s) (RB_TYPE_P((s), T_STRING) && CLASS_OF(s) == rb_cString)
 
-enum {
-    cmp_opt_Integer,
-    cmp_opt_String,
-    cmp_opt_Float,
-    cmp_optimizable_count
-};
+#define CMP_OPTIMIZABLE(type) BASIC_OP_UNREDEFINED_P(BOP_CMP, type##_REDEFINED_OP_FLAG)
 
-struct cmp_opt_data {
-    unsigned int opt_methods;
-    unsigned int opt_inited;
-};
-
-#define NEW_CMP_OPT_MEMO(type, value) \
-    NEW_PARTIAL_MEMO_FOR(type, value, cmp_opt)
-#define CMP_OPTIMIZABLE_BIT(type) (1U << TOKEN_PASTE(cmp_opt_,type))
-#define CMP_OPTIMIZABLE(data, type) \
-    (((data).opt_inited & CMP_OPTIMIZABLE_BIT(type)) ? \
-     ((data).opt_methods & CMP_OPTIMIZABLE_BIT(type)) : \
-     (((data).opt_inited |= CMP_OPTIMIZABLE_BIT(type)), \
-      rb_method_basic_definition_p(TOKEN_PASTE(rb_c,type), id_cmp) && \
-      ((data).opt_methods |= CMP_OPTIMIZABLE_BIT(type))))
-
-#define OPTIMIZED_CMP(a, b, data) \
-    ((FIXNUM_P(a) && FIXNUM_P(b) && CMP_OPTIMIZABLE(data, Integer)) ? \
+#define OPTIMIZED_CMP(a, b) \
+    ((FIXNUM_P(a) && FIXNUM_P(b) && CMP_OPTIMIZABLE(INTEGER)) ? \
      (((long)a > (long)b) ? 1 : ((long)a < (long)b) ? -1 : 0) : \
-     (STRING_P(a) && STRING_P(b) && CMP_OPTIMIZABLE(data, String)) ? \
+     (STRING_P(a) && STRING_P(b) && CMP_OPTIMIZABLE(STRING)) ? \
      rb_str_cmp(a, b) : \
-     (RB_FLOAT_TYPE_P(a) && RB_FLOAT_TYPE_P(b) && CMP_OPTIMIZABLE(data, Float)) ? \
+     (RB_FLOAT_TYPE_P(a) && RB_FLOAT_TYPE_P(b) && CMP_OPTIMIZABLE(FLOAT)) ? \
      rb_float_cmp(a, b) : \
      rb_cmpint(rb_funcallv(a, id_cmp, 1, &b), a, b))
 
diff --git a/internal/cont.h b/internal/cont.h
index 5ab120e9ab..c3b091668a 100644
--- a/internal/cont.h
+++ b/internal/cont.h
@@ -9,16 +9,24 @@
  * @brief      Internal header for Fiber.
  */
 #include "ruby/ruby.h"          /* for VALUE */
+#include "iseq.h"
 
 struct rb_thread_struct;        /* in vm_core.h */
 struct rb_fiber_struct;         /* in cont.c */
+struct rb_execution_context_struct; /* in vm_core.c */
 
 /* cont.c */
 void rb_fiber_reset_root_local_storage(struct rb_thread_struct *);
 void ruby_register_rollback_func_for_ensure(VALUE (*ensure_func)(VALUE), VALUE (*rollback_func)(VALUE));
-void rb_fiber_init_mjit_cont(struct rb_fiber_struct *fiber);
+void rb_jit_cont_init(void);
+void rb_jit_cont_each_iseq(rb_iseq_callback callback, void *data);
+void rb_jit_cont_finish(void);
+
+// Copy locals from the current execution to the specified fiber.
+VALUE rb_fiber_inherit_storage(struct rb_execution_context_struct *ec, struct rb_fiber_struct *fiber);
 
 VALUE rb_fiberptr_self(struct rb_fiber_struct *fiber);
 unsigned int rb_fiberptr_blocking(struct rb_fiber_struct *fiber);
+struct rb_execution_context_struct * rb_fiberptr_get_ec(struct rb_fiber_struct *fiber);
 
 #endif /* INTERNAL_CONT_H */
diff --git a/internal/encoding.h b/internal/encoding.h
index c48cb24b04..a3b81bd388 100644
--- a/internal/encoding.h
+++ b/internal/encoding.h
@@ -12,6 +12,9 @@
 #include "ruby/encoding.h"      /* for rb_encoding */
 
 #define rb_enc_autoload_p(enc) (!rb_enc_mbmaxlen(enc))
+#define rb_is_usascii_enc(enc) ((enc) == rb_usascii_encoding())
+#define rb_is_ascii8bit_enc(enc) ((enc) == rb_ascii8bit_encoding())
+#define rb_is_locale_enc(enc) ((enc) == rb_locale_encoding())
 
 /* encoding.c */
 ID rb_id_encoding(void);
@@ -24,7 +27,6 @@ int rb_encdb_dummy(const char *name);
 void rb_encdb_declare(const char *name);
 void rb_enc_set_base(const char *name, const char *orig);
 int rb_enc_set_dummy(int index);
-void rb_encdb_set_unicode(int index);
 PUREFUNC(int rb_data_is_encoding(VALUE obj));
 
 #endif /* INTERNAL_ENCODING_H */
diff --git a/internal/eval.h b/internal/eval.h
index 73bb656d96..e594d8516d 100644
--- a/internal/eval.h
+++ b/internal/eval.h
@@ -21,6 +21,7 @@ extern ID ruby_static_id_status;
 VALUE rb_refinement_module_get_refined_class(VALUE module);
 void rb_class_modify_check(VALUE);
 NORETURN(VALUE rb_f_raise(int argc, VALUE *argv));
+VALUE rb_top_main_class(const char *method);
 
 /* eval_error.c */
 VALUE rb_get_backtrace(VALUE info);
diff --git a/internal/fixnum.h b/internal/fixnum.h
index cdb60ee1ff..8c251adef1 100644
--- a/internal/fixnum.h
+++ b/internal/fixnum.h
@@ -18,7 +18,7 @@
 #if HAVE_LONG_LONG && SIZEOF_LONG * 2 <= SIZEOF_LONG_LONG
 # define DLONG LONG_LONG
 # define DL2NUM(x) LL2NUM(x)
-#elif defined(HAVE_INT128_T)
+#elif defined(HAVE_INT128_T) && !(defined(__OpenBSD__) && defined(__mips64__))
 # define DLONG int128_t
 # define DL2NUM(x) (RB_FIXABLE(x) ? LONG2FIX(x) : rb_int128t2big(x))
 VALUE rb_int128t2big(int128_t n); /* in bignum.c */
diff --git a/internal/gc.h b/internal/gc.h
index 3346089754..e54a5dce9d 100644
--- a/internal/gc.h
+++ b/internal/gc.h
@@ -67,12 +67,16 @@ struct rb_objspace; /* in vm_core.h */
     rb_obj_write((VALUE)(a), UNALIGNED_MEMBER_ACCESS((VALUE *)(slot)), \
                  (VALUE)(b), __FILE__, __LINE__)
 
-#if USE_RVARGC
-# define SIZE_POOL_COUNT 4
+// We use SIZE_POOL_COUNT number of shape IDs for transitions out of different size pools
+// The next available shapd ID will be the SPECIAL_CONST_SHAPE_ID
+#if USE_RVARGC && (SIZEOF_UINT64_T == SIZEOF_VALUE)
+# define SIZE_POOL_COUNT 5
 #else
 # define SIZE_POOL_COUNT 1
 #endif
 
+#define RCLASS_EXT_EMBEDDED (SIZE_POOL_COUNT > 1)
+
 typedef struct ractor_newobj_size_pool_cache {
     struct RVALUE *freelist;
     struct heap_page *using_page;
diff --git a/internal/hash.h b/internal/hash.h
index 657e5eff3c..64832c9610 100644
--- a/internal/hash.h
+++ b/internal/hash.h
@@ -73,6 +73,7 @@ VALUE rb_hash_default_value(VALUE hash, VALUE key);
 VALUE rb_hash_set_default_proc(VALUE hash, VALUE proc);
 long rb_dbl_long_hash(double d);
 st_table *rb_init_identtable(void);
+st_index_t rb_any_hash(VALUE a);
 VALUE rb_to_hash_type(VALUE obj);
 VALUE rb_hash_key_str(VALUE);
 VALUE rb_hash_values(VALUE hash);
diff --git a/internal/imemo.h b/internal/imemo.h
index ea36c4514f..91b524e0a6 100644
--- a/internal/imemo.h
+++ b/internal/imemo.h
@@ -10,7 +10,7 @@
  */
 #include "ruby/internal/config.h"
 #include <stddef.h>             /* for size_t */
-#include "internal/array.h"     /* for rb_ary_tmp_new_fill */
+#include "internal/array.h"     /* for rb_ary_hidden_new_fill */
 #include "internal/gc.h"        /* for RB_OBJ_WRITE */
 #include "ruby/internal/stdbool.h"     /* for bool */
 #include "ruby/ruby.h"          /* for rb_block_call_func_t */
@@ -121,14 +121,13 @@ struct MEMO {
 #define MEMO_NEW(a, b, c) ((struct MEMO *)rb_imemo_new(imemo_memo, (VALUE)(a), (VALUE)(b), (VALUE)(c), 0))
 #define MEMO_FOR(type, value) ((type *)RARRAY_PTR(value))
 #define NEW_MEMO_FOR(type, value) \
-  ((value) = rb_ary_tmp_new_fill(type_roomof(type, VALUE)), MEMO_FOR(type, value))
+  ((value) = rb_ary_hidden_new_fill(type_roomof(type, VALUE)), MEMO_FOR(type, value))
 #define NEW_PARTIAL_MEMO_FOR(type, value, member) \
-  ((value) = rb_ary_tmp_new_fill(type_roomof(type, VALUE)), \
+  ((value) = rb_ary_hidden_new_fill(type_roomof(type, VALUE)), \
    rb_ary_set_len((value), offsetof(type, member) / sizeof(VALUE)), \
    MEMO_FOR(type, value))
 
 typedef struct rb_imemo_tmpbuf_struct rb_imemo_tmpbuf_t;
-VALUE rb_imemo_new(enum imemo_type type, VALUE v1, VALUE v2, VALUE v3, VALUE v0);
 rb_imemo_tmpbuf_t *rb_imemo_tmpbuf_parser_heap(void *buf, rb_imemo_tmpbuf_t *old_heap, size_t cnt);
 struct vm_ifunc *rb_vm_ifunc_new(rb_block_call_func_t func, const void *data, int min_argc, int max_argc);
 void rb_strterm_mark(VALUE obj);
diff --git a/internal/numeric.h b/internal/numeric.h
index 19069cb3bc..89bc54b307 100644
--- a/internal/numeric.h
+++ b/internal/numeric.h
@@ -35,12 +35,16 @@ enum ruby_num_rounding_mode {
     RUBY_NUM_ROUND_DEFAULT = ROUND_DEFAULT,
 };
 
+/* same as internal.h */
+#define numberof(array) ((int)(sizeof(array) / sizeof((array)[0])))
+#define roomof(x, y) (((x) + (y) - 1) / (y))
+#define type_roomof(x, y) roomof(sizeof(x), sizeof(y))
+
 #if SIZEOF_DOUBLE <= SIZEOF_VALUE
 typedef double rb_float_value_type;
 #else
 typedef struct {
-    VALUE values[(SIZEOF_DOUBLE + SIZEOF_VALUE - 1) / SIZEOF_VALUE];
-    /* roomof() needs internal.h, and the order of some macros may matter */
+    VALUE values[roomof(SIZEOF_DOUBLE, SIZEOF_VALUE)];
 } rb_float_value_type;
 #endif
 
diff --git a/internal/object.h b/internal/object.h
index f560fb7f9f..7b54e13dd2 100644
--- a/internal/object.h
+++ b/internal/object.h
@@ -9,11 +9,6 @@
  * @brief      Internal header for Object.
  */
 #include "ruby/ruby.h"          /* for VALUE */
-#include "internal/class.h"     /* for RCLASS_IV_INDEX_TBL */
-
-#ifdef ROBJECT_IV_INDEX_TBL
-# undef ROBJECT_IV_INDEX_TBL
-#endif
 
 /* object.c */
 VALUE rb_class_search_ancestor(VALUE klass, VALUE super);
@@ -22,11 +17,10 @@ double rb_num_to_dbl(VALUE val);
 VALUE rb_obj_dig(int argc, VALUE *argv, VALUE self, VALUE notfound);
 VALUE rb_immutable_obj_clone(int, VALUE *, VALUE);
 VALUE rb_check_convert_type_with_id(VALUE,int,const char*,ID);
-int rb_bool_expected(VALUE, const char *);
+int rb_bool_expected(VALUE, const char *, int raise);
 static inline void RBASIC_CLEAR_CLASS(VALUE obj);
 static inline void RBASIC_SET_CLASS_RAW(VALUE obj, VALUE klass);
 static inline void RBASIC_SET_CLASS(VALUE obj, VALUE klass);
-static inline struct st_table *ROBJECT_IV_INDEX_TBL_inline(VALUE obj);
 
 RUBY_SYMBOL_EXPORT_BEGIN
 /* object.c (export) */
@@ -64,20 +58,4 @@ RBASIC_SET_CLASS(VALUE obj, VALUE klass)
     RBASIC_SET_CLASS_RAW(obj, klass);
     RB_OBJ_WRITTEN(obj, oldv, klass);
 }
-
-RBIMPL_ATTR_PURE()
-static inline struct st_table *
-ROBJECT_IV_INDEX_TBL_inline(VALUE obj)
-{
-    if (RB_FL_ANY_RAW(obj, ROBJECT_EMBED)) {
-        VALUE klass = rb_obj_class(obj);
-        return RCLASS_IV_INDEX_TBL(klass);
-    }
-    else {
-        const struct RObject *const ptr = ROBJECT(obj);
-        return ptr->as.heap.iv_index_tbl;
-    }
-}
-#define ROBJECT_IV_INDEX_TBL ROBJECT_IV_INDEX_TBL_inline
-
 #endif /* INTERNAL_OBJECT_H */
diff --git a/internal/parse.h b/internal/parse.h
index d9f5b56bc5..f242c384ad 100644
--- a/internal/parse.h
+++ b/internal/parse.h
@@ -15,6 +15,8 @@ struct rb_iseq_struct;          /* in vm_core.h */
 VALUE rb_parser_set_yydebug(VALUE, VALUE);
 void *rb_parser_load_file(VALUE parser, VALUE name);
 void rb_parser_keep_script_lines(VALUE vparser);
+void rb_parser_error_tolerant(VALUE vparser);
+void rb_parser_keep_tokens(VALUE vparser);
 
 RUBY_SYMBOL_EXPORT_BEGIN
 VALUE rb_parser_set_context(VALUE, const struct rb_iseq_struct *, int);
diff --git a/internal/string.h b/internal/string.h
index 18b01862f7..12edbff2b1 100644
--- a/internal/string.h
+++ b/internal/string.h
@@ -43,6 +43,8 @@ char *rb_str_to_cstr(VALUE str);
 const char *ruby_escaped_char(int c);
 void rb_str_make_independent(VALUE str);
 int rb_enc_str_coderange_scan(VALUE str, rb_encoding *enc);
+int rb_ascii8bit_appendable_encoding_index(rb_encoding *enc, unsigned int code);
+VALUE rb_str_include(VALUE str, VALUE arg);
 
 static inline bool STR_EMBED_P(VALUE str);
 static inline bool STR_SHARED_P(VALUE str);
@@ -59,6 +61,10 @@ void rb_str_tmp_frozen_release(VALUE str, VALUE tmp);
 VALUE rb_setup_fake_str(struct RString *fake_str, const char *name, long len, rb_encoding *enc);
 VALUE rb_str_upto_each(VALUE, VALUE, int, int (*each)(VALUE, VALUE), VALUE);
 VALUE rb_str_upto_endless_each(VALUE, int (*each)(VALUE, VALUE), VALUE);
+void rb_str_make_embedded(VALUE);
+size_t rb_str_size_as_embedded(VALUE);
+bool rb_str_reembeddable_p(VALUE);
+void rb_str_update_shared_ary(VALUE str, VALUE old_root, VALUE new_root);
 RUBY_SYMBOL_EXPORT_END
 
 MJIT_SYMBOL_EXPORT_BEGIN
@@ -100,7 +106,7 @@ STR_EMBED_P(VALUE str)
 static inline bool
 STR_SHARED_P(VALUE str)
 {
-    return FL_ALL_RAW(str, STR_NOEMBED | ELTS_SHARED);
+    return FL_ALL_RAW(str, STR_NOEMBED | STR_SHARED);
 }
 
 static inline bool
diff --git a/internal/symbol.h b/internal/symbol.h
index 4f041330f9..30c81ea004 100644
--- a/internal/symbol.h
+++ b/internal/symbol.h
@@ -30,6 +30,7 @@ PUREFUNC(int rb_is_attrset_sym(VALUE sym));
 ID rb_make_internal_id(void);
 ID rb_make_temporary_id(size_t n);
 void rb_gc_free_dsymbol(VALUE);
+int rb_static_id_valid_p(ID id);
 
 #if __has_builtin(__builtin_constant_p)
 #define rb_sym_intern_ascii_cstr(ptr) \
diff --git a/internal/thread.h b/internal/thread.h
index 919ad96580..c3e54de683 100644
--- a/internal/thread.h
+++ b/internal/thread.h
@@ -20,6 +20,7 @@ struct rb_thread_struct;        /* in vm_core.h */
 #define COVERAGE_TARGET_BRANCHES 2
 #define COVERAGE_TARGET_METHODS  4
 #define COVERAGE_TARGET_ONESHOT_LINES 8
+#define COVERAGE_TARGET_EVAL 16
 
 VALUE rb_obj_is_mutex(VALUE obj);
 VALUE rb_suppress_tracing(VALUE (*func)(VALUE), VALUE arg);
@@ -28,6 +29,7 @@ VALUE rb_get_coverages(void);
 int rb_get_coverage_mode(void);
 VALUE rb_default_coverage(int);
 VALUE rb_thread_shield_new(void);
+bool rb_thread_shield_owned(VALUE self);
 VALUE rb_thread_shield_wait(VALUE self);
 VALUE rb_thread_shield_release(VALUE self);
 VALUE rb_thread_shield_destroy(VALUE self);
@@ -35,6 +37,7 @@ int rb_thread_to_be_killed(VALUE thread);
 void rb_mutex_allow_trap(VALUE self, int val);
 VALUE rb_uninterruptible(VALUE (*b_proc)(VALUE), VALUE data);
 VALUE rb_mutex_owned_p(VALUE self);
+VALUE rb_exec_recursive_outer_mid(VALUE (*f)(VALUE g, VALUE h, int r), VALUE g, VALUE h, ID mid);
 
 int rb_thread_wait_for_single_fd(int fd, int events, struct timeval * timeout);
 
diff --git a/internal/time.h b/internal/time.h
index a3bf0587ec..e21b3574f6 100644
--- a/internal/time.h
+++ b/internal/time.h
@@ -28,7 +28,10 @@ struct timeval rb_time_timeval(VALUE);
 RUBY_SYMBOL_EXPORT_BEGIN
 /* time.c (export) */
 void ruby_reset_leap_second_info(void);
-void ruby_reset_timezone(void);
+#ifdef RBIMPL_ATTR_DEPRECATED_INTERNAL_ONLY
+RBIMPL_ATTR_DEPRECATED_INTERNAL_ONLY()
+#endif
+void ruby_reset_timezone(const char *);
 RUBY_SYMBOL_EXPORT_END
 
 #endif /* INTERNAL_TIME_H */
diff --git a/internal/variable.h b/internal/variable.h
index 4b67bef907..6dec6a6759 100644
--- a/internal/variable.h
+++ b/internal/variable.h
@@ -13,10 +13,11 @@
 #include "constant.h"           /* for rb_const_entry_t */
 #include "ruby/internal/stdbool.h"     /* for bool */
 #include "ruby/ruby.h"          /* for VALUE */
+#include "shape.h"              /* for rb_shape_t */
 
 /* global variable */
 
-#define ROBJECT_TRANSIENT_FLAG    FL_USER13
+#define ROBJECT_TRANSIENT_FLAG    FL_USER2
 
 /* variable.c */
 void rb_gc_mark_global_tbl(void);
@@ -24,7 +25,6 @@ void rb_gc_update_global_tbl(void);
 size_t rb_generic_ivar_memsize(VALUE);
 VALUE rb_search_class_path(VALUE);
 VALUE rb_attr_delete(VALUE, ID);
-VALUE rb_ivar_lookup(VALUE obj, ID id, VALUE undef);
 void rb_autoload_str(VALUE mod, ID id, VALUE file);
 VALUE rb_autoload_at_p(VALUE, ID, int);
 NORETURN(VALUE rb_mod_const_missing(VALUE,VALUE));
@@ -35,7 +35,10 @@ void rb_gvar_ractor_local(const char *name);
 static inline bool ROBJ_TRANSIENT_P(VALUE obj);
 static inline void ROBJ_TRANSIENT_SET(VALUE obj);
 static inline void ROBJ_TRANSIENT_UNSET(VALUE obj);
-uint32_t rb_obj_ensure_iv_index_mapping(VALUE obj, ID id);
+
+struct gen_ivtbl;
+int rb_gen_ivtbl_get(VALUE obj, ID id, struct gen_ivtbl **ivtbl);
+int rb_obj_evacuate_ivs_to_hash_table(ID key, VALUE val, st_data_t arg);
 
 RUBY_SYMBOL_EXPORT_BEGIN
 /* variable.c (export) */
@@ -47,11 +50,15 @@ void rb_iv_tbl_copy(VALUE dst, VALUE src);
 RUBY_SYMBOL_EXPORT_END
 
 MJIT_SYMBOL_EXPORT_BEGIN
+VALUE rb_ivar_lookup(VALUE obj, ID id, VALUE undef);
 VALUE rb_gvar_get(ID);
 VALUE rb_gvar_set(ID, VALUE);
 VALUE rb_gvar_defined(ID);
 void rb_const_warn_if_deprecated(const rb_const_entry_t *, VALUE, ID);
-void rb_init_iv_list(VALUE obj);
+rb_shape_t * rb_grow_iv_list(VALUE obj);
+void rb_ensure_iv_list_size(VALUE obj, uint32_t len, uint32_t newsize);
+struct gen_ivtbl *rb_ensure_generic_iv_list_size(VALUE obj, rb_shape_t *shape, uint32_t newsize);
+attr_index_t rb_obj_ivar_set(VALUE obj, ID id, VALUE val);
 MJIT_SYMBOL_EXPORT_END
 
 static inline bool
diff --git a/internal/vm.h b/internal/vm.h
index c6c6b2ccc2..cf245c6579 100644
--- a/internal/vm.h
+++ b/internal/vm.h
@@ -40,7 +40,7 @@ enum method_missing_reason {
 };
 
 /* vm_insnhelper.h */
-rb_serial_t rb_next_class_serial(void);
+VALUE rb_vm_push_frame_fname(struct rb_execution_context_struct *ec, VALUE fname);
 
 /* vm.c */
 VALUE rb_obj_is_thread(VALUE obj);
diff --git a/io.c b/io.c
index 32704d9d17..99ec59da29 100644
--- a/io.c
+++ b/io.c
@@ -75,10 +75,6 @@
 #include <sys/fcntl.h>
 #endif
 
-#if !HAVE_OFF_T && !defined(off_t)
-# define off_t  long
-#endif
-
 #ifdef HAVE_SYS_TIME_H
 # include <sys/time.h>
 #endif
@@ -149,10 +145,6 @@
 #define O_ACCMODE (O_RDONLY | O_WRONLY | O_RDWR)
 #endif
 
-#if SIZEOF_OFF_T > SIZEOF_LONG && !defined(HAVE_LONG_LONG)
-# error off_t is bigger than long, but you have no long long...
-#endif
-
 #ifndef PIPE_BUF
 # ifdef _POSIX_PIPE_BUF
 #  define PIPE_BUF _POSIX_PIPE_BUF
@@ -175,6 +167,8 @@ off_t __syscall(quad_t number, ...);
 #define IO_RBUF_CAPA_FOR(fptr) (NEED_READCONV(fptr) ? IO_CBUF_CAPA_MIN : IO_RBUF_CAPA_MIN)
 #define IO_WBUF_CAPA_MIN  8192
 
+#define IO_MAX_BUFFER_GROWTH 8 * 1024 * 1024 // 8MB
+
 /* define system APIs */
 #ifdef _WIN32
 #undef open
@@ -186,6 +180,7 @@ off_t __syscall(quad_t number, ...);
 VALUE rb_cIO;
 VALUE rb_eEOFError;
 VALUE rb_eIOError;
+VALUE rb_eIOTimeoutError;
 VALUE rb_mWaitReadable;
 VALUE rb_mWaitWritable;
 
@@ -254,7 +249,7 @@ rb_update_max_fd(int fd)
     }
 
     while (max_fd < afd) {
-	max_fd = ATOMIC_CAS(max_file_descriptor, max_fd, afd);
+        max_fd = ATOMIC_CAS(max_file_descriptor, max_fd, afd);
     }
 }
 
@@ -299,7 +294,7 @@ rb_fix_detect_o_cloexec(int fd)
         rb_bug("rb_fix_detect_o_cloexec: fcntl(%d, F_GETFD) failed: %s", fd, strerror(errno));
 
     if (flags & FD_CLOEXEC)
-	return 1;
+        return 1;
 #endif /* fall through if O_CLOEXEC does not work: */
     rb_maygvl_fd_fix_cloexec(fd);
     return 0;
@@ -339,13 +334,13 @@ rb_cloexec_open(const char *pathname, int flags, mode_t mode)
 
     if (ret < 0) return ret;
     if (ret <= 2 || o_cloexec_state == 0) {
-	rb_maygvl_fd_fix_cloexec(ret);
+        rb_maygvl_fd_fix_cloexec(ret);
     }
     else if (o_cloexec_state > 0) {
-	return ret;
+        return ret;
     }
     else {
-	o_cloexec_state = rb_fix_detect_o_cloexec(ret);
+        o_cloexec_state = rb_fix_detect_o_cloexec(ret);
     }
     return ret;
 }
@@ -501,7 +496,7 @@ rb_cloexec_fcntl_dupfd(int fd, int minfd)
 
 #if defined(_WIN32)
 #define WAIT_FD_IN_WIN32(fptr) \
-    (rb_w32_io_cancelable_p((fptr)->fd) ? Qnil : rb_io_wait(fptr->self, RB_INT2NUM(RUBY_IO_READABLE), Qnil))
+    (rb_w32_io_cancelable_p((fptr)->fd) ? Qnil : rb_io_wait(fptr->self, RB_INT2NUM(RUBY_IO_READABLE), RUBY_IO_TIMEOUT_DEFAULT))
 #else
 #define WAIT_FD_IN_WIN32(fptr)
 #endif
@@ -598,19 +593,19 @@ raise_on_write(rb_io_t *fptr, int e, VALUE errinfo)
 
 #define NEED_NEWLINE_DECORATOR_ON_READ_CHECK(fptr) do {\
     if (NEED_NEWLINE_DECORATOR_ON_READ(fptr)) {\
-	if (((fptr)->mode & FMODE_READABLE) &&\
-	    !((fptr)->encs.ecflags & ECONV_NEWLINE_DECORATOR_MASK)) {\
-	    setmode((fptr)->fd, O_BINARY);\
-	}\
-	else {\
-	    setmode((fptr)->fd, O_TEXT);\
-	}\
+        if (((fptr)->mode & FMODE_READABLE) &&\
+            !((fptr)->encs.ecflags & ECONV_NEWLINE_DECORATOR_MASK)) {\
+            setmode((fptr)->fd, O_BINARY);\
+        }\
+        else {\
+            setmode((fptr)->fd, O_TEXT);\
+        }\
     }\
 } while(0)
 
 #define SET_UNIVERSAL_NEWLINE_DECORATOR_IF_ENC2(enc2, ecflags) do {\
     if ((enc2) && ((ecflags) & ECONV_DEFAULT_NEWLINE_DECORATOR)) {\
-	(ecflags) |= ECONV_UNIVERSAL_NEWLINE_DECORATOR;\
+        (ecflags) |= ECONV_UNIVERSAL_NEWLINE_DECORATOR;\
     }\
 } while(0)
 
@@ -620,7 +615,7 @@ raise_on_write(rb_io_t *fptr, int e, VALUE errinfo)
 static void
 io_unread(rb_io_t *fptr)
 {
-    off_t r, pos;
+    rb_off_t r, pos;
     ssize_t read_size;
     long i;
     long newlines = 0;
@@ -630,28 +625,28 @@ io_unread(rb_io_t *fptr)
 
     rb_io_check_closed(fptr);
     if (fptr->rbuf.len == 0 || fptr->mode & FMODE_DUPLEX) {
-	return;
+        return;
     }
 
     errno = 0;
     if (!rb_w32_fd_is_text(fptr->fd)) {
-	r = lseek(fptr->fd, -fptr->rbuf.len, SEEK_CUR);
-	if (r < 0 && errno) {
-	    if (errno == ESPIPE)
-		fptr->mode |= FMODE_DUPLEX;
-	    return;
-	}
+        r = lseek(fptr->fd, -fptr->rbuf.len, SEEK_CUR);
+        if (r < 0 && errno) {
+            if (errno == ESPIPE)
+                fptr->mode |= FMODE_DUPLEX;
+            return;
+        }
 
-	fptr->rbuf.off = 0;
-	fptr->rbuf.len = 0;
-	return;
+        fptr->rbuf.off = 0;
+        fptr->rbuf.len = 0;
+        return;
     }
 
     pos = lseek(fptr->fd, 0, SEEK_CUR);
     if (pos < 0 && errno) {
-	if (errno == ESPIPE)
-	    fptr->mode |= FMODE_DUPLEX;
-	return;
+        if (errno == ESPIPE)
+            fptr->mode |= FMODE_DUPLEX;
+        return;
     }
 
     /* add extra offset for removed '\r' in rbuf */
@@ -660,36 +655,36 @@ io_unread(rb_io_t *fptr)
 
     /* if the end of rbuf is '\r', rbuf doesn't have '\r' within rbuf.len */
     if (*(fptr->rbuf.ptr + fptr->rbuf.capa - 1) == '\r') {
-	newlines++;
+        newlines++;
     }
 
     for (i = 0; i < fptr->rbuf.len; i++) {
-	if (*p == '\n') newlines++;
-	if (extra_max == newlines) break;
-	p++;
+        if (*p == '\n') newlines++;
+        if (extra_max == newlines) break;
+        p++;
     }
 
     buf = ALLOC_N(char, fptr->rbuf.len + newlines);
     while (newlines >= 0) {
-	r = lseek(fptr->fd, pos - fptr->rbuf.len - newlines, SEEK_SET);
-	if (newlines == 0) break;
-	if (r < 0) {
-	    newlines--;
-	    continue;
-	}
-	read_size = _read(fptr->fd, buf, fptr->rbuf.len + newlines);
-	if (read_size < 0) {
-	    int e = errno;
-	    free(buf);
-	    rb_syserr_fail_path(e, fptr->pathv);
-	}
-	if (read_size == fptr->rbuf.len) {
-	    lseek(fptr->fd, r, SEEK_SET);
-	    break;
-	}
-	else {
-	    newlines--;
-	}
+        r = lseek(fptr->fd, pos - fptr->rbuf.len - newlines, SEEK_SET);
+        if (newlines == 0) break;
+        if (r < 0) {
+            newlines--;
+            continue;
+        }
+        read_size = _read(fptr->fd, buf, fptr->rbuf.len + newlines);
+        if (read_size < 0) {
+            int e = errno;
+            free(buf);
+            rb_syserr_fail_path(e, fptr->pathv);
+        }
+        if (read_size == fptr->rbuf.len) {
+            lseek(fptr->fd, r, SEEK_SET);
+            break;
+        }
+        else {
+            newlines--;
+        }
     }
     free(buf);
     fptr->rbuf.off = 0;
@@ -710,7 +705,7 @@ set_binary_mode_with_seek_cur(rb_io_t *fptr)
     if (!rb_w32_fd_is_text(fptr->fd)) return O_BINARY;
 
     if (fptr->rbuf.len == 0 || fptr->mode & FMODE_DUPLEX) {
-	return setmode(fptr->fd, O_BINARY);
+        return setmode(fptr->fd, O_BINARY);
     }
     flush_before_seek(fptr);
     return setmode(fptr->fd, O_BINARY);
@@ -779,7 +774,7 @@ void
 rb_io_check_initialized(rb_io_t *fptr)
 {
     if (!fptr) {
-	rb_raise(rb_eIOError, "uninitialized stream");
+        rb_raise(rb_eIOError, "uninitialized stream");
     }
 }
 
@@ -827,10 +822,10 @@ rb_io_set_write_io(VALUE io, VALUE w)
     VALUE write_io;
     rb_io_t *fptr = rb_io_get_fptr(io);
     if (!RTEST(w)) {
-	w = 0;
+        w = 0;
     }
     else {
-	GetWriteIO(w);
+        GetWriteIO(w);
     }
     write_io = fptr->tied_io_for_writing;
     fptr->tied_io_for_writing = w;
@@ -839,6 +834,54 @@ rb_io_set_write_io(VALUE io, VALUE w)
 
 /*
  *  call-seq:
+ *    timeout -> duration or nil
+ *
+ *  Get the internal timeout duration or nil if it was not set.
+ *
+ */
+VALUE
+rb_io_timeout(VALUE self)
+{
+    rb_io_t *fptr = rb_io_get_fptr(self);
+
+    return fptr->timeout;
+}
+
+/*
+ *  call-seq:
+ *    timeout = duration -> duration
+ *    timeout = nil -> nil
+ *
+ *  Set the internal timeout to the specified duration or nil. The timeout
+ *  applies to all blocking operations where possible.
+ *
+ *  This affects the following methods (but is not limited to): #gets, #puts,
+ *  #read, #write, #wait_readable and #wait_writable. This also affects
+ *  blocking socket operations like Socket#accept and Socket#connect.
+ *
+ *  Some operations like File#open and IO#close are not affected by the
+ *  timeout. A timeout during a write operation may leave the IO in an
+ *  inconsistent state, e.g. data was partially written. Generally speaking, a
+ *  timeout is a last ditch effort to prevent an application from hanging on
+ *  slow I/O operations, such as those that occur during a slowloris attack.
+ */
+VALUE
+rb_io_set_timeout(VALUE self, VALUE timeout)
+{
+    // Validate it:
+    if (RTEST(timeout)) {
+        rb_time_interval(timeout);
+    }
+
+    rb_io_t *fptr = rb_io_get_fptr(self);
+
+    fptr->timeout = timeout;
+
+    return self;
+}
+
+/*
+ *  call-seq:
  *    IO.try_convert(object) -> new_io or nil
  *
  *  Attempts to convert +object+ into an \IO object via method +to_io+;
@@ -859,7 +902,7 @@ rb_io_s_try_convert(VALUE dummy, VALUE io)
 static void
 io_unread(rb_io_t *fptr)
 {
-    off_t r;
+    rb_off_t r;
     rb_io_check_closed(fptr);
     if (fptr->rbuf.len == 0 || fptr->mode & FMODE_DUPLEX)
         return;
@@ -889,17 +932,17 @@ io_ungetbyte(VALUE str, rb_io_t *fptr)
         fptr->rbuf.off = 0;
         fptr->rbuf.len = 0;
 #if SIZEOF_LONG > SIZEOF_INT
-	if (len > INT_MAX)
-	    rb_raise(rb_eIOError, "ungetbyte failed");
+        if (len > INT_MAX)
+            rb_raise(rb_eIOError, "ungetbyte failed");
 #endif
-	if (len > min_capa)
-	    fptr->rbuf.capa = (int)len;
-	else
-	    fptr->rbuf.capa = min_capa;
+        if (len > min_capa)
+            fptr->rbuf.capa = (int)len;
+        else
+            fptr->rbuf.capa = min_capa;
         fptr->rbuf.ptr = ALLOC_N(char, fptr->rbuf.capa);
     }
     if (fptr->rbuf.capa < len + fptr->rbuf.len) {
-	rb_raise(rb_eIOError, "ungetbyte failed");
+        rb_raise(rb_eIOError, "ungetbyte failed");
     }
     if (fptr->rbuf.off < len) {
         MEMMOVE(fptr->rbuf.ptr+fptr->rbuf.capa-fptr->rbuf.len,
@@ -936,15 +979,15 @@ rb_io_check_char_readable(rb_io_t *fptr)
 {
     rb_io_check_closed(fptr);
     if (!(fptr->mode & FMODE_READABLE)) {
-	rb_raise(rb_eIOError, "not opened for reading");
+        rb_raise(rb_eIOError, "not opened for reading");
     }
     if (fptr->wbuf.len) {
         if (io_fflush(fptr) < 0)
             rb_sys_fail_on_write(fptr);
     }
     if (fptr->tied_io_for_writing) {
-	rb_io_t *wfptr;
-	GetOpenFile(fptr->tied_io_for_writing, wfptr);
+        rb_io_t *wfptr;
+        GetOpenFile(fptr->tied_io_for_writing, wfptr);
         if (io_fflush(wfptr) < 0)
             rb_sys_fail_on_write(wfptr);
     }
@@ -955,7 +998,7 @@ rb_io_check_byte_readable(rb_io_t *fptr)
 {
     rb_io_check_char_readable(fptr);
     if (READ_CHAR_PENDING(fptr)) {
-	rb_raise(rb_eIOError, "byte oriented read for character buffered IO");
+        rb_raise(rb_eIOError, "byte oriented read for character buffered IO");
     }
 }
 
@@ -969,7 +1012,7 @@ static rb_encoding*
 io_read_encoding(rb_io_t *fptr)
 {
     if (fptr->encs.enc) {
-	return fptr->encs.enc;
+        return fptr->encs.enc;
     }
     return rb_default_external_encoding();
 }
@@ -978,7 +1021,7 @@ static rb_encoding*
 io_input_encoding(rb_io_t *fptr)
 {
     if (fptr->encs.enc2) {
-	return fptr->encs.enc2;
+        return fptr->encs.enc2;
     }
     return io_read_encoding(fptr);
 }
@@ -988,7 +1031,7 @@ rb_io_check_writable(rb_io_t *fptr)
 {
     rb_io_check_closed(fptr);
     if (!(fptr->mode & FMODE_WRITABLE)) {
-	rb_raise(rb_eIOError, "not opened for writing");
+        rb_raise(rb_eIOError, "not opened for writing");
     }
     if (fptr->rbuf.len) {
         io_unread(fptr);
@@ -1008,7 +1051,7 @@ void
 rb_io_read_check(rb_io_t *fptr)
 {
     if (!READ_DATA_PENDING(fptr)) {
-        rb_io_wait(fptr->self, RB_INT2NUM(RUBY_IO_READABLE), Qnil);
+        rb_io_wait(fptr->self, RB_INT2NUM(RUBY_IO_READABLE), RUBY_IO_TIMEOUT_DEFAULT);
     }
     return;
 }
@@ -1017,8 +1060,8 @@ int
 rb_gc_for_fd(int err)
 {
     if (err == EMFILE || err == ENFILE || err == ENOMEM) {
-	rb_gc();
-	return 1;
+        rb_gc();
+        return 1;
     }
     return 0;
 }
@@ -1030,13 +1073,13 @@ ruby_dup(int orig)
 
     fd = rb_cloexec_dup(orig);
     if (fd < 0) {
-	int e = errno;
-	if (rb_gc_for_fd(e)) {
-	    fd = rb_cloexec_dup(orig);
-	}
-	if (fd < 0) {
-	    rb_syserr_fail(e, 0);
-	}
+        int e = errno;
+        if (rb_gc_for_fd(e)) {
+            fd = rb_cloexec_dup(orig);
+        }
+        if (fd < 0) {
+            rb_syserr_fail(e, 0);
+        }
     }
     rb_update_max_fd(fd);
     return fd;
@@ -1060,62 +1103,124 @@ struct io_internal_read_struct {
     VALUE th;
     rb_io_t *fptr;
     int nonblock;
+    int fd;
+
     void *buf;
     size_t capa;
+    struct timeval *timeout;
 };
 
 struct io_internal_write_struct {
+    VALUE th;
+    rb_io_t *fptr;
+    int nonblock;
     int fd;
+
     const void *buf;
     size_t capa;
+    struct timeval *timeout;
 };
 
 #ifdef HAVE_WRITEV
 struct io_internal_writev_struct {
+    VALUE th;
+    rb_io_t *fptr;
+    int nonblock;
     int fd;
+
     int iovcnt;
     const struct iovec *iov;
+    struct timeval *timeout;
 };
 #endif
 
-static int nogvl_wait_for(VALUE th, rb_io_t *fptr, short events);
+static int nogvl_wait_for(VALUE th, rb_io_t *fptr, short events, struct timeval *timeout);
+
+/**
+ * Wait for the given events on the given file descriptor.
+ * Returns -1 if an error or timeout occurred. +errno+ will be set.
+ * Returns the event mask if an event occurred.
+ */
+static inline int
+io_internal_wait(VALUE thread, rb_io_t *fptr, int error, int events, struct timeval *timeout)
+{
+    int ready = nogvl_wait_for(thread, fptr, events, timeout);
+
+    if (ready > 0) {
+        return ready;
+    }
+    else if (ready == 0) {
+        errno = ETIMEDOUT;
+        return -1;
+    }
+
+    errno = error;
+    return -1;
+}
+
 static VALUE
 internal_read_func(void *ptr)
 {
     struct io_internal_read_struct *iis = ptr;
-    ssize_t r;
-retry:
-    r = read(iis->fptr->fd, iis->buf, iis->capa);
-    if (r < 0 && !iis->nonblock) {
-        int e = errno;
-        if (io_again_p(e)) {
-            if (nogvl_wait_for(iis->th, iis->fptr, RB_WAITFD_IN) != -1) {
+    ssize_t result;
+
+    if (iis->timeout && !iis->nonblock) {
+        if (io_internal_wait(iis->th, iis->fptr, 0, RB_WAITFD_IN, iis->timeout) == -1) {
+            return -1;
+        }
+    }
+
+  retry:
+    result = read(iis->fd, iis->buf, iis->capa);
+
+    if (result < 0 && !iis->nonblock) {
+        if (io_again_p(errno)) {
+            if (io_internal_wait(iis->th, iis->fptr, errno, RB_WAITFD_IN, iis->timeout) == -1) {
+                return -1;
+            }
+            else {
                 goto retry;
             }
-            errno = e;
         }
     }
-    return r;
+
+    return result;
 }
 
 #if defined __APPLE__
-# define do_write_retry(code) do {ret = code;} while (ret == -1 && errno == EPROTOTYPE)
+# define do_write_retry(code) do {result = code;} while (result == -1 && errno == EPROTOTYPE)
 #else
-# define do_write_retry(code) ret = code
+# define do_write_retry(code) result = code
 #endif
+
 static VALUE
 internal_write_func(void *ptr)
 {
     struct io_internal_write_struct *iis = ptr;
-    ssize_t ret;
+    ssize_t result;
+
+    if (iis->timeout && !iis->nonblock) {
+        if (io_internal_wait(iis->th, iis->fptr, 0, RB_WAITFD_OUT, iis->timeout) == -1) {
+            return -1;
+        }
+    }
+
+  retry:
     do_write_retry(write(iis->fd, iis->buf, iis->capa));
-    return (VALUE)ret;
-}
 
-static void*
-internal_write_func2(void *ptr)
-{
-    return (void*)internal_write_func(ptr);
+    if (result < 0 && !iis->nonblock) {
+        int e = errno;
+        if (io_again_p(e)) {
+            if (io_internal_wait(iis->th, iis->fptr, errno, RB_WAITFD_OUT, iis->timeout) == -1) {
+                return -1;
+            }
+            else {
+                goto retry;
+            }
+        }
+    }
+
+    return result;
 }
 
 #ifdef HAVE_WRITEV
@@ -1123,20 +1228,40 @@ static VALUE
 internal_writev_func(void *ptr)
 {
     struct io_internal_writev_struct *iis = ptr;
-    ssize_t ret;
+    ssize_t result;
+
+    if (iis->timeout && !iis->nonblock) {
+        if (io_internal_wait(iis->th, iis->fptr, 0, RB_WAITFD_OUT, iis->timeout) == -1) {
+            return -1;
+        }
+    }
+
+  retry:
     do_write_retry(writev(iis->fd, iis->iov, iis->iovcnt));
-    return (VALUE)ret;
+
+    if (result < 0 && !iis->nonblock) {
+        if (io_again_p(errno)) {
+            if (io_internal_wait(iis->th, iis->fptr, errno, RB_WAITFD_OUT, iis->timeout) == -1) {
+                return -1;
+            }
+            else {
+                goto retry;
+            }
+        }
+    }
+
+    return result;
 }
 #endif
 
 static ssize_t
-rb_read_internal(rb_io_t *fptr, void *buf, size_t count)
+rb_io_read_memory(rb_io_t *fptr, void *buf, size_t count)
 {
     VALUE scheduler = rb_fiber_scheduler_current();
     if (scheduler != Qnil) {
         VALUE result = rb_fiber_scheduler_io_read_memory(scheduler, fptr->self, buf, count, 0);
 
-        if (result != Qundef) {
+        if (!UNDEF_P(result)) {
             return rb_fiber_scheduler_io_result_apply(result);
         }
     }
@@ -1145,58 +1270,90 @@ rb_read_internal(rb_io_t *fptr, void *buf, size_t count)
         .th = rb_thread_current(),
         .fptr = fptr,
         .nonblock = 0,
+        .fd = fptr->fd,
+
         .buf = buf,
-        .capa = count
+        .capa = count,
+        .timeout = NULL,
     };
 
+    struct timeval timeout_storage;
+
+    if (fptr->timeout != Qnil) {
+        timeout_storage = rb_time_interval(fptr->timeout);
+        iis.timeout = &timeout_storage;
+    }
+
     return (ssize_t)rb_thread_io_blocking_region(internal_read_func, &iis, fptr->fd);
 }
 
 static ssize_t
-rb_write_internal(rb_io_t *fptr, const void *buf, size_t count)
+rb_io_write_memory(rb_io_t *fptr, const void *buf, size_t count)
 {
     VALUE scheduler = rb_fiber_scheduler_current();
     if (scheduler != Qnil) {
         VALUE result = rb_fiber_scheduler_io_write_memory(scheduler, fptr->self, buf, count, 0);
 
-        if (result != Qundef) {
+        if (!UNDEF_P(result)) {
             return rb_fiber_scheduler_io_result_apply(result);
         }
     }
 
     struct io_internal_write_struct iis = {
+        .th = rb_thread_current(),
+        .fptr = fptr,
+        .nonblock = 0,
         .fd = fptr->fd,
+
         .buf = buf,
-        .capa = count
+        .capa = count,
+        .timeout = NULL
     };
 
-    if (fptr->write_lock && rb_mutex_owned_p(fptr->write_lock))
-        return (ssize_t)rb_thread_call_without_gvl2(internal_write_func2, &iis, RUBY_UBF_IO, NULL);
-    else
-        return (ssize_t)rb_thread_io_blocking_region(internal_write_func, &iis, fptr->fd);
+    struct timeval timeout_storage;
+
+    if (fptr->timeout != Qnil) {
+        timeout_storage = rb_time_interval(fptr->timeout);
+        iis.timeout = &timeout_storage;
+    }
+
+    return (ssize_t)rb_thread_io_blocking_region(internal_write_func, &iis, fptr->fd);
 }
 
 #ifdef HAVE_WRITEV
 static ssize_t
 rb_writev_internal(rb_io_t *fptr, const struct iovec *iov, int iovcnt)
 {
+    if (!iovcnt) return 0;
+
     VALUE scheduler = rb_fiber_scheduler_current();
     if (scheduler != Qnil) {
-        for (int i = 0; i < iovcnt; i += 1) {
-            VALUE result = rb_fiber_scheduler_io_write_memory(scheduler, fptr->self, iov[i].iov_base, iov[i].iov_len, 0);
+        // This path assumes at least one `iov`:
+        VALUE result = rb_fiber_scheduler_io_write_memory(scheduler, fptr->self, iov[0].iov_base, iov[0].iov_len, 0);
 
-            if (result != Qundef) {
-                return rb_fiber_scheduler_io_result_apply(result);
-            }
+        if (!UNDEF_P(result)) {
+            return rb_fiber_scheduler_io_result_apply(result);
         }
     }
 
     struct io_internal_writev_struct iis = {
+        .th = rb_thread_current(),
+        .fptr = fptr,
+        .nonblock = 0,
         .fd = fptr->fd,
+
         .iov = iov,
         .iovcnt = iovcnt,
+        .timeout = NULL
     };
 
+    struct timeval timeout_storage;
+
+    if (fptr->timeout != Qnil) {
+        timeout_storage = rb_time_interval(fptr->timeout);
+        iis.timeout = &timeout_storage;
+    }
+
     return (ssize_t)rb_thread_io_blocking_region(internal_writev_func, &iis, fptr->fd);
 }
 #endif
@@ -1209,28 +1366,18 @@ io_flush_buffer_sync(void *arg)
     ssize_t r = write(fptr->fd, fptr->wbuf.ptr+fptr->wbuf.off, (size_t)l);
 
     if (fptr->wbuf.len <= r) {
-	fptr->wbuf.off = 0;
-	fptr->wbuf.len = 0;
-	return 0;
+        fptr->wbuf.off = 0;
+        fptr->wbuf.len = 0;
+        return 0;
     }
+
     if (0 <= r) {
-	fptr->wbuf.off += (int)r;
-	fptr->wbuf.len -= (int)r;
-	errno = EAGAIN;
+        fptr->wbuf.off += (int)r;
+        fptr->wbuf.len -= (int)r;
+        errno = EAGAIN;
     }
-    return (VALUE)-1;
-}
 
-static void*
-io_flush_buffer_sync2(void *arg)
-{
-    VALUE result = io_flush_buffer_sync(arg);
-
-    /*
-     * rb_thread_call_without_gvl2 uses 0 as interrupted.
-     * So, we need to avoid to use 0.
-     */
-    return !result ? (void*)1 : (void*)result;
+    return (VALUE)-1;
 }
 
 static VALUE
@@ -1240,36 +1387,14 @@ io_flush_buffer_async(VALUE arg)
     return rb_thread_io_blocking_region(io_flush_buffer_sync, fptr, fptr->fd);
 }
 
-static VALUE
-io_flush_buffer_async2(VALUE arg)
-{
-    rb_io_t *fptr = (rb_io_t *)arg;
-    VALUE ret;
-
-    ret = (VALUE)rb_thread_call_without_gvl2(io_flush_buffer_sync2, fptr, RUBY_UBF_IO, NULL);
-
-    if (!ret) {
-	/* pending async interrupt is there. */
-	errno = EAGAIN;
-	return -1;
-    }
-    else if (ret == 1) {
-	return 0;
-    }
-    return ret;
-}
-
 static inline int
 io_flush_buffer(rb_io_t *fptr)
 {
-    if (fptr->write_lock) {
-	if (rb_mutex_owned_p(fptr->write_lock))
-	    return (int)io_flush_buffer_async2((VALUE)fptr);
-	else
-	    return (int)rb_mutex_synchronize(fptr->write_lock, io_flush_buffer_async2, (VALUE)fptr);
+    if (!NIL_P(fptr->write_lock) && rb_mutex_owned_p(fptr->write_lock)) {
+        return (int)io_flush_buffer_async((VALUE)fptr);
     }
     else {
-	return (int)io_flush_buffer_async((VALUE)fptr);
+        return (int)rb_mutex_synchronize(fptr->write_lock, io_flush_buffer_async, (VALUE)fptr);
     }
 }
 
@@ -1282,7 +1407,7 @@ io_fflush(rb_io_t *fptr)
         return 0;
 
     while (fptr->wbuf.len > 0 && io_flush_buffer(fptr) != 0) {
-        if (!rb_io_maybe_wait_writable(errno, fptr->self, Qnil))
+        if (!rb_io_maybe_wait_writable(errno, fptr->self, RUBY_IO_TIMEOUT_DEFAULT))
             return -1;
 
         rb_io_check_closed(fptr);
@@ -1306,6 +1431,10 @@ rb_io_wait(VALUE io, VALUE events, VALUE timeout)
     struct timeval tv_storage;
     struct timeval *tv = NULL;
 
+    if (NIL_OR_UNDEF_P(timeout)) {
+        timeout = fptr->timeout;
+    }
+
     if (timeout != Qnil) {
         tv_storage = rb_time_interval(timeout);
         tv = &tv_storage;
@@ -1524,7 +1653,7 @@ make_writeconv(rb_io_t *fptr)
         ecflags = fptr->encs.ecflags & ~ECONV_NEWLINE_DECORATOR_READ_MASK;
         ecopts = fptr->encs.ecopts;
 
-        if (!fptr->encs.enc || (fptr->encs.enc == rb_ascii8bit_encoding() && !fptr->encs.enc2)) {
+        if (!fptr->encs.enc || (rb_is_ascii8bit_enc(fptr->encs.enc) && !fptr->encs.enc2)) {
             /* no encoding conversion */
             fptr->writeconv_pre_ecflags = 0;
             fptr->writeconv_pre_ecopts = Qnil;
@@ -1580,72 +1709,111 @@ struct write_arg {
 };
 
 #ifdef HAVE_WRITEV
-static VALUE
-io_binwrite_string(VALUE arg)
+static ssize_t
+io_binwrite_string_internal(rb_io_t *fptr, const char *ptr, long length)
 {
-    struct binwrite_arg *p = (struct binwrite_arg *)arg;
-    rb_io_t *fptr = p->fptr;
-    long r;
-
     if (fptr->wbuf.len) {
-	struct iovec iov[2];
+        struct iovec iov[2];
+
+        iov[0].iov_base = fptr->wbuf.ptr+fptr->wbuf.off;
+        iov[0].iov_len = fptr->wbuf.len;
+        iov[1].iov_base = (void*)ptr;
+        iov[1].iov_len = length;
 
-	iov[0].iov_base = fptr->wbuf.ptr+fptr->wbuf.off;
-	iov[0].iov_len = fptr->wbuf.len;
-	iov[1].iov_base = (char *)p->ptr;
-	iov[1].iov_len = p->length;
+        ssize_t result = rb_writev_internal(fptr, iov, 2);
 
-	r = rb_writev_internal(fptr, iov, 2);
+        if (result < 0)
+            return result;
 
-        if (r < 0)
-            return r;
+        if (result >= fptr->wbuf.len) {
+            // We wrote more than the internal buffer:
+            result -= fptr->wbuf.len;
+            fptr->wbuf.off = 0;
+            fptr->wbuf.len = 0;
+        }
+        else {
+            // We only wrote less data than the internal buffer:
+            fptr->wbuf.off += (int)result;
+            fptr->wbuf.len -= (int)result;
 
-	if (fptr->wbuf.len <= r) {
-	    r -= fptr->wbuf.len;
-	    fptr->wbuf.off = 0;
-	    fptr->wbuf.len = 0;
-	}
-	else {
-	    fptr->wbuf.off += (int)r;
-	    fptr->wbuf.len -= (int)r;
-	    r = 0L;
-	}
+            result = 0;
+        }
+
+        return result;
     }
     else {
-	r = rb_write_internal(fptr, p->ptr, p->length);
+        return rb_io_write_memory(fptr, ptr, length);
     }
-
-    return r;
 }
 #else
+static ssize_t
+io_binwrite_string_internal(rb_io_t *fptr, const char *ptr, long length)
+{
+    long remaining = length;
+
+    if (fptr->wbuf.len) {
+        if (fptr->wbuf.len+length <= fptr->wbuf.capa) {
+            if (fptr->wbuf.capa < fptr->wbuf.off+fptr->wbuf.len+length) {
+                MEMMOVE(fptr->wbuf.ptr, fptr->wbuf.ptr+fptr->wbuf.off, char, fptr->wbuf.len);
+                fptr->wbuf.off = 0;
+            }
+
+            MEMMOVE(fptr->wbuf.ptr+fptr->wbuf.off+fptr->wbuf.len, ptr, char, length);
+            fptr->wbuf.len += (int)length;
+
+            // We copied the entire incoming data to the internal buffer:
+            remaining = 0;
+        }
+
+        // Flush the internal buffer:
+        if (io_fflush(fptr) < 0) {
+            return -1;
+        }
+
+        // If all the data was buffered, we are done:
+        if (remaining == 0) {
+            return length;
+        }
+    }
+
+    // Otherwise, we should write the data directly:
+    return rb_io_write_memory(fptr, ptr, length);
+}
+#endif
+
 static VALUE
 io_binwrite_string(VALUE arg)
 {
     struct binwrite_arg *p = (struct binwrite_arg *)arg;
-    rb_io_t *fptr = p->fptr;
-    long l, len;
 
-    l = len = p->length;
+    const char *ptr = p->ptr;
+    size_t remaining = p->length;
 
-    if (fptr->wbuf.len) {
-	if (fptr->wbuf.len+len <= fptr->wbuf.capa) {
-	    if (fptr->wbuf.capa < fptr->wbuf.off+fptr->wbuf.len+len) {
-		MEMMOVE(fptr->wbuf.ptr, fptr->wbuf.ptr+fptr->wbuf.off, char, fptr->wbuf.len);
-		fptr->wbuf.off = 0;
-	    }
-	    MEMMOVE(fptr->wbuf.ptr+fptr->wbuf.off+fptr->wbuf.len, p->ptr, char, len);
-	    fptr->wbuf.len += (int)len;
-	    l = 0;
-	}
-	if (io_fflush(fptr) < 0)
-	    return -2L; /* fail in fflush */
-	if (l == 0)
-	    return len;
+    while (remaining) {
+        // Write as much as possible:
+        ssize_t result = io_binwrite_string_internal(p->fptr, ptr, remaining);
+
+        if (result == 0) {
+            // If only the internal buffer is written, result will be zero [bytes of given data written]. This means we
+            // should try again immediately.
+        }
+        else if (result > 0) {
+            if ((size_t)result == remaining) break;
+            ptr += result;
+            remaining -= result;
+        }
+        // Wait for it to become writable:
+        else if (rb_io_maybe_wait_writable(errno, p->fptr->self, RUBY_IO_TIMEOUT_DEFAULT)) {
+            rb_io_check_closed(p->fptr);
+        }
+        else {
+            // The error was unrelated to waiting for it to become writable, so we fail:
+            return -1;
+        }
     }
 
-    return rb_write_internal(p->fptr, p->ptr, p->length);
+    return p->length;
 }
-#endif
 
 inline static void
 io_allocate_write_buffer(rb_io_t *fptr, int sync)
@@ -1655,70 +1823,66 @@ io_allocate_write_buffer(rb_io_t *fptr, int sync)
         fptr->wbuf.len = 0;
         fptr->wbuf.capa = IO_WBUF_CAPA_MIN;
         fptr->wbuf.ptr = ALLOC_N(char, fptr->wbuf.capa);
+    }
+
+    if (NIL_P(fptr->write_lock)) {
         fptr->write_lock = rb_mutex_new();
         rb_mutex_allow_trap(fptr->write_lock, 1);
     }
 }
 
+static inline int
+io_binwrite_requires_flush_write(rb_io_t *fptr, long len, int nosync)
+{
+    // If the requested operation was synchronous and the output mode is synchronus or a TTY:
+    if (!nosync && (fptr->mode & (FMODE_SYNC|FMODE_TTY)))
+        return 1;
+
+    // If the amount of data we want to write exceeds the internal buffer:
+    if (fptr->wbuf.ptr && fptr->wbuf.capa <= fptr->wbuf.len + len)
+        return 1;
+
+    // Otherwise, we can append to the internal buffer:
+    return 0;
+}
+
 static long
 io_binwrite(VALUE str, const char *ptr, long len, rb_io_t *fptr, int nosync)
 {
-    long n, r, offset = 0;
+    if (len <= 0) return len;
 
-    /* don't write anything if current thread has a pending interrupt. */
+    // Don't write anything if current thread has a pending interrupt:
     rb_thread_check_ints();
 
-    if ((n = len) <= 0) return n;
-
     io_allocate_write_buffer(fptr, !nosync);
 
-    if ((!nosync && (fptr->mode & (FMODE_SYNC|FMODE_TTY))) ||
-        (fptr->wbuf.ptr && fptr->wbuf.capa <= fptr->wbuf.len + len)) {
+    if (io_binwrite_requires_flush_write(fptr, len, nosync)) {
         struct binwrite_arg arg;
 
         arg.fptr = fptr;
         arg.str = str;
-      retry:
-        arg.ptr = ptr + offset;
-        arg.length = n;
+        arg.ptr = ptr;
+        arg.length = len;
 
-        if (fptr->write_lock) {
-            r = rb_mutex_synchronize(fptr->write_lock, io_binwrite_string, (VALUE)&arg);
+        if (!NIL_P(fptr->write_lock)) {
+            return rb_mutex_synchronize(fptr->write_lock, io_binwrite_string, (VALUE)&arg);
         }
         else {
-            r = io_binwrite_string((VALUE)&arg);
-        }
-
-        /* xxx: other threads may modify given string. */
-        if (r == n) return len;
-        if (0 <= r) {
-            offset += r;
-            n -= r;
-            errno = EAGAIN;
+            return io_binwrite_string((VALUE)&arg);
         }
-
-        if (r == -2L)
-            return -1L;
-        if (rb_io_maybe_wait_writable(errno, fptr->self, Qnil)) {
-            rb_io_check_closed(fptr);
-
-            if (offset < len)
-                goto retry;
+    }
+    else {
+        if (fptr->wbuf.off) {
+            if (fptr->wbuf.len)
+                MEMMOVE(fptr->wbuf.ptr, fptr->wbuf.ptr+fptr->wbuf.off, char, fptr->wbuf.len);
+            fptr->wbuf.off = 0;
         }
 
-        return -1L;
-    }
+        MEMMOVE(fptr->wbuf.ptr+fptr->wbuf.off+fptr->wbuf.len, ptr, char, len);
+        fptr->wbuf.len += (int)len;
 
-    if (fptr->wbuf.off) {
-        if (fptr->wbuf.len)
-            MEMMOVE(fptr->wbuf.ptr, fptr->wbuf.ptr+fptr->wbuf.off, char, fptr->wbuf.len);
-        fptr->wbuf.off = 0;
+        return len;
     }
-
-    MEMMOVE(fptr->wbuf.ptr+fptr->wbuf.off+fptr->wbuf.len, ptr+offset, char, len);
-    fptr->wbuf.len += (int)len;
-
-    return len;
 }
 
 # define MODE_BTMODE(a,b,c) ((fmode & FMODE_BINMODE) ? (b) : \
@@ -1733,7 +1897,7 @@ do_writeconv(VALUE str, rb_io_t *fptr, int *converted)
 {
     if (NEED_WRITECONV(fptr)) {
         VALUE common_encoding = Qnil;
-	SET_BINARY_MODE(fptr);
+        SET_BINARY_MODE(fptr);
 
         make_writeconv(fptr);
 
@@ -1757,27 +1921,27 @@ do_writeconv(VALUE str, rb_io_t *fptr, int *converted)
         if (!NIL_P(common_encoding)) {
             str = rb_str_encode(str, common_encoding,
                 fptr->writeconv_pre_ecflags, fptr->writeconv_pre_ecopts);
-	    *converted = 1;
+            *converted = 1;
         }
 
         if (fptr->writeconv) {
             str = rb_econv_str_convert(fptr->writeconv, str, ECONV_PARTIAL_INPUT);
-	    *converted = 1;
+            *converted = 1;
         }
     }
 #if RUBY_CRLF_ENVIRONMENT
 #define fmode (fptr->mode)
     else if (MODE_BTMODE(DEFAULT_TEXTMODE,0,1)) {
-	if ((fptr->mode & FMODE_READABLE) &&
-	    !(fptr->encs.ecflags & ECONV_NEWLINE_DECORATOR_MASK)) {
-	    setmode(fptr->fd, O_BINARY);
-	}
-	else {
-	    setmode(fptr->fd, O_TEXT);
-	}
-	if (!rb_enc_asciicompat(rb_enc_get(str))) {
-	    rb_raise(rb_eArgError, "ASCII incompatible string written for text mode IO without encoding conversion: %s",
-	    rb_enc_name(rb_enc_get(str)));
+        if ((fptr->mode & FMODE_READABLE) &&
+            !(fptr->encs.ecflags & ECONV_NEWLINE_DECORATOR_MASK)) {
+            setmode(fptr->fd, O_BINARY);
+        }
+        else {
+            setmode(fptr->fd, O_TEXT);
+        }
+        if (!rb_enc_asciicompat(rb_enc_get(str))) {
+            rb_raise(rb_eArgError, "ASCII incompatible string written for text mode IO without encoding conversion: %s",
+            rb_enc_name(rb_enc_get(str)));
         }
     }
 #undef fmode
@@ -1792,15 +1956,17 @@ io_fwrite(VALUE str, rb_io_t *fptr, int nosync)
     VALUE tmp;
     long n, len;
     const char *ptr;
+
 #ifdef _WIN32
     if (fptr->mode & FMODE_TTY) {
-	long len = rb_w32_write_console(str, fptr->fd);
-	if (len > 0) return len;
+        long len = rb_w32_write_console(str, fptr->fd);
+        if (len > 0) return len;
     }
 #endif
+
     str = do_writeconv(str, fptr, &converted);
     if (converted)
-	OBJ_FREEZE(str);
+        OBJ_FREEZE(str);
 
     tmp = rb_str_tmp_frozen_acquire(str);
     RSTRING_GETMEM(tmp, ptr, len);
@@ -1830,10 +1996,12 @@ io_write(VALUE io, VALUE str, int nosync)
     io = GetWriteIO(io);
     str = rb_obj_as_string(str);
     tmp = rb_io_check_io(io);
+
     if (NIL_P(tmp)) {
-	/* port is not IO, call write method for it. */
-	return rb_funcall(io, id_write, 1, str);
+        /* port is not IO, call write method for it. */
+        return rb_funcall(io, id_write, 1, str);
     }
+
     io = tmp;
     if (RSTRING_LEN(str) == 0) return INT2FIX(0);
 
@@ -1849,105 +2017,124 @@ io_write(VALUE io, VALUE str, int nosync)
 #ifdef HAVE_WRITEV
 struct binwritev_arg {
     rb_io_t *fptr;
-    const struct iovec *iov;
+    struct iovec *iov;
     int iovcnt;
+    size_t total;
 };
 
 static VALUE
-call_writev_internal(VALUE arg)
+io_binwritev_internal(VALUE arg)
 {
     struct binwritev_arg *p = (struct binwritev_arg *)arg;
-    return rb_writev_internal(p->fptr, p->iov, p->iovcnt);
+
+    size_t remaining = p->total;
+    size_t offset = 0;
+
+    rb_io_t *fptr = p->fptr;
+    struct iovec *iov = p->iov;
+    int iovcnt = p->iovcnt;
+
+    while (remaining) {
+        long result = rb_writev_internal(fptr, iov, iovcnt);
+
+        if (result >= 0) {
+            offset += result;
+            if (fptr->wbuf.ptr && fptr->wbuf.len) {
+                if (offset < (size_t)fptr->wbuf.len) {
+                    fptr->wbuf.off += result;
+                    fptr->wbuf.len -= result;
+                }
+                else {
+                    offset -= (size_t)fptr->wbuf.len;
+                    fptr->wbuf.off = 0;
+                    fptr->wbuf.len = 0;
+                }
+            }
+
+            if (offset == p->total) {
+                return p->total;
+            }
+
+            while (result >= (ssize_t)iov->iov_len) {
+                /* iovcnt > 0 */
+                result -= iov->iov_len;
+                iov->iov_len = 0;
+                iov++;
+
+                if (!--iovcnt) {
+                    // I don't believe this code path can ever occur.
+                    return offset;
+                }
+            }
+
+            iov->iov_base = (char *)iov->iov_base + result;
+            iov->iov_len -= result;
+        }
+        else if (rb_io_maybe_wait_writable(errno, fptr->self, RUBY_IO_TIMEOUT_DEFAULT)) {
+            rb_io_check_closed(fptr);
+        }
+        else {
+            return -1;
+        }
+    }
+
+    return offset;
 }
 
 static long
 io_binwritev(struct iovec *iov, int iovcnt, rb_io_t *fptr)
 {
-    int i;
-    long r, total = 0, written_len = 0;
-
-    /* don't write anything if current thread has a pending interrupt. */
+    // Don't write anything if current thread has a pending interrupt:
     rb_thread_check_ints();
 
     if (iovcnt == 0) return 0;
-    for (i = 1; i < iovcnt; i++) total += iov[i].iov_len;
+
+    size_t total = 0;
+    for (int i = 1; i < iovcnt; i++) total += iov[i].iov_len;
 
     io_allocate_write_buffer(fptr, 1);
 
     if (fptr->wbuf.ptr && fptr->wbuf.len) {
-        long offset = fptr->wbuf.off + fptr->wbuf.len;
-        if (offset + total <= fptr->wbuf.capa) {
-            for (i = 1; i < iovcnt; i++) {
+        // The end of the buffered data:
+        size_t offset = fptr->wbuf.off + fptr->wbuf.len;
+
+        if (offset + total <= (size_t)fptr->wbuf.capa) {
+            for (int i = 1; i < iovcnt; i++) {
                 memcpy(fptr->wbuf.ptr+offset, iov[i].iov_base, iov[i].iov_len);
                 offset += iov[i].iov_len;
             }
 
             fptr->wbuf.len += total;
+
             return total;
         }
         else {
             iov[0].iov_base = fptr->wbuf.ptr + fptr->wbuf.off;
-            iov[0].iov_len  = fptr->wbuf.len;
+            iov[0].iov_len = fptr->wbuf.len;
         }
     }
     else {
+        // The first iov is reserved for the internal buffer, and it's empty.
         iov++;
-        if (!--iovcnt) return 0;
-    }
-
-  retry:
-    if (fptr->write_lock) {
-        struct binwritev_arg arg;
-        arg.fptr = fptr;
-        arg.iov  = iov;
-        arg.iovcnt = iovcnt;
-        r = rb_mutex_synchronize(fptr->write_lock, call_writev_internal, (VALUE)&arg);
-    }
-    else {
-        r = rb_writev_internal(fptr, iov, iovcnt);
-    }
-
-    if (r >= 0) {
-        written_len += r;
-        if (fptr->wbuf.ptr && fptr->wbuf.len) {
-            if (written_len < fptr->wbuf.len) {
-                fptr->wbuf.off += r;
-                fptr->wbuf.len -= r;
-            }
-            else {
-                written_len -= fptr->wbuf.len;
-                fptr->wbuf.off = 0;
-                fptr->wbuf.len = 0;
-            }
-        }
 
-        if (written_len == total) return total;
-
-        while (r >= (ssize_t)iov->iov_len) {
-            /* iovcnt > 0 */
-            r -= iov->iov_len;
-            iov->iov_len = 0;
-            iov++;
-
-            if (!--iovcnt) {
-                // assert(written_len == total);
-
-                return total;
-            }
+        if (!--iovcnt) {
+            // If there are no other io vectors we are done.
+            return 0;
         }
+    }
 
-        iov->iov_base = (char *)iov->iov_base + r;
-        iov->iov_len -= r;
+    struct binwritev_arg arg;
+    arg.fptr = fptr;
+    arg.iov = iov;
+    arg.iovcnt = iovcnt;
+    arg.total = total;
 
-        errno = EAGAIN;
+    if (!NIL_P(fptr->write_lock)) {
+        return rb_mutex_synchronize(fptr->write_lock, io_binwritev_internal, (VALUE)&arg);
     }
-
-    if (rb_io_maybe_wait_writable(errno, fptr->self, Qnil)) {
-        rb_io_check_closed(fptr);
-        goto retry;
+    else {
+        return io_binwritev_internal((VALUE)&arg);
     }
-
-    return -1L;
 }
 
 static long
@@ -2048,7 +2235,8 @@ io_writev(int argc, const VALUE *argv, VALUE io)
  *    write(*objects) -> integer
  *
  *  Writes each of the given +objects+ to +self+,
- *  which must be opened for writing (see IO@Modes);
+ *  which must be opened for writing
+ *  (see {Access Modes}[rdoc-ref:File@Access+Modes]);
  *  returns the total number bytes written;
  *  each of +objects+ that is not a string is converted via method +to_s+:
  *
@@ -2060,6 +2248,7 @@ io_writev(int argc, const VALUE *argv, VALUE io)
  *    Hello, World!
  *    foobar2
  *
+ *  Related: IO#read.
  */
 
 static VALUE
@@ -2096,8 +2285,7 @@ rb_io_writev(VALUE io, int argc, const VALUE *argv)
 
         do rb_io_write(io, *argv++); while (--argc);
 
-        /* unused right now */
-        return argv[0];
+        return Qnil;
     }
 
     return rb_funcallv(io, id_write, argc, argv);
@@ -2108,7 +2296,7 @@ rb_io_writev(VALUE io, int argc, const VALUE *argv)
  *    self << object -> self
  *
  *  Writes the given +object+ to +self+,
- *  which must be opened for writing (see IO@Modes);
+ *  which must be opened for writing (see {Access Modes}[rdoc-ref:File@Access+Modes]);
  *  returns +self+;
  *  if +object+ is not a string, it is converted via method +to_s+:
  *
@@ -2138,7 +2326,7 @@ nogvl_fsync(void *ptr)
 
 #ifdef _WIN32
     if (GetFileType((HANDLE)rb_w32_get_osfhandle(fptr->fd)) != FILE_TYPE_DISK)
-	return 0;
+        return 0;
 #endif
     return (VALUE)fsync(fptr->fd);
 }
@@ -2208,7 +2396,7 @@ static VALUE
 rb_io_tell(VALUE io)
 {
     rb_io_t *fptr;
-    off_t pos;
+    rb_off_t pos;
 
     GetOpenFile(io, fptr);
     pos = io_tell(fptr);
@@ -2221,7 +2409,7 @@ static VALUE
 rb_io_seek(VALUE io, VALUE offset, int whence)
 {
     rb_io_t *fptr;
-    off_t pos;
+    rb_off_t pos;
 
     pos = NUM2OFFT(offset);
     GetOpenFile(io, fptr);
@@ -2305,7 +2493,7 @@ rb_io_seek_m(int argc, VALUE *argv, VALUE io)
     int whence = SEEK_SET;
 
     if (rb_scan_args(argc, argv, "11", &offset, &ptrname) == 2) {
-	whence = interpret_seek_whence(ptrname);
+        whence = interpret_seek_whence(ptrname);
     }
 
     return rb_io_seek(io, offset, whence);
@@ -2332,7 +2520,7 @@ static VALUE
 rb_io_set_pos(VALUE io, VALUE offset)
 {
     rb_io_t *fptr;
-    off_t pos;
+    rb_off_t pos;
 
     pos = NUM2OFFT(offset);
     GetOpenFile(io, fptr);
@@ -2376,11 +2564,11 @@ rb_io_rewind(VALUE io)
     GetOpenFile(io, fptr);
     if (io_seek(fptr, 0L, 0) < 0 && errno) rb_sys_fail_path(fptr->pathv);
     if (io == ARGF.current_file) {
-	ARGF.lineno -= fptr->lineno;
+        ARGF.lineno -= fptr->lineno;
     }
     fptr->lineno = 0;
     if (fptr->readconv) {
-	clear_readconv(fptr);
+        clear_readconv(fptr);
     }
 
     return INT2FIX(0);
@@ -2389,12 +2577,12 @@ rb_io_rewind(VALUE io)
 static int
 fptr_wait_readable(rb_io_t *fptr)
 {
-    int ret = rb_io_maybe_wait_readable(errno, fptr->self, Qnil);
+    int result = rb_io_maybe_wait_readable(errno, fptr->self, RUBY_IO_TIMEOUT_DEFAULT);
 
-    if (ret)
+    if (result)
         rb_io_check_closed(fptr);
 
-    return ret;
+    return result;
 }
 
 static int
@@ -2413,7 +2601,7 @@ io_fillbuf(rb_io_t *fptr)
     }
     if (fptr->rbuf.len == 0) {
       retry:
-        r = rb_read_internal(fptr, fptr->rbuf.ptr, fptr->rbuf.capa);
+        r = rb_io_read_memory(fptr, fptr->rbuf.ptr, fptr->rbuf.capa);
 
         if (r < 0) {
             if (fptr_wait_readable(fptr))
@@ -2450,7 +2638,7 @@ io_fillbuf(rb_io_t *fptr)
  *    f.close
  *
  *  Raises an exception unless the stream is opened for reading;
- *  see {Mode}[rdoc-ref:IO@Mode].
+ *  see {Mode}[rdoc-ref:File@Access+Modes].
  *
  *  If +self+ is a stream such as pipe or socket, this method
  *  blocks until the other end sends some data or closes it:
@@ -2470,7 +2658,7 @@ io_fillbuf(rb_io_t *fptr)
  *  IO#sysread may not behave as you intend with IO#eof?, unless you
  *  call IO#rewind first (which is not available for some streams).
  *
- *  I#eof? is an alias for IO#eof.
+ *  IO#eof? is an alias for IO#eof.
  *
  */
 
@@ -2487,7 +2675,7 @@ rb_io_eof(VALUE io)
     READ_CHECK(fptr);
 #if RUBY_CRLF_ENVIRONMENT
     if (!NEED_READCONV(fptr) && NEED_NEWLINE_DECORATOR_ON_READ(fptr)) {
-	return RBOOL(eof(fptr->fd));;
+        return RBOOL(eof(fptr->fd));;
     }
 #endif
     return RBOOL(io_fillbuf(fptr) < 0);
@@ -2554,10 +2742,10 @@ rb_io_set_sync(VALUE io, VALUE sync)
     io = GetWriteIO(io);
     GetOpenFile(io, fptr);
     if (RTEST(sync)) {
-	fptr->mode |= FMODE_SYNC;
+        fptr->mode |= FMODE_SYNC;
     }
     else {
-	fptr->mode &= ~FMODE_SYNC;
+        fptr->mode &= ~FMODE_SYNC;
     }
     return sync;
 }
@@ -2591,7 +2779,7 @@ rb_io_fsync(VALUE io)
     if (io_fflush(fptr) < 0)
         rb_sys_fail_on_write(fptr);
     if ((int)rb_thread_io_blocking_region(nogvl_fsync, fptr, fptr->fd) < 0)
-	rb_sys_fail_path(fptr->pathv);
+        rb_sys_fail_path(fptr->pathv);
     return INT2FIX(0);
 }
 #else
@@ -2613,7 +2801,7 @@ nogvl_fdatasync(void *ptr)
 
 #ifdef _WIN32
     if (GetFileType((HANDLE)rb_w32_get_osfhandle(fptr->fd)) != FILE_TYPE_DISK)
-	return 0;
+        return 0;
 #endif
     return (VALUE)fdatasync(fptr->fd);
 }
@@ -2641,7 +2829,7 @@ rb_io_fdatasync(VALUE io)
         rb_sys_fail_on_write(fptr);
 
     if ((int)rb_thread_io_blocking_region(nogvl_fdatasync, fptr, fptr->fd) == 0)
-	return INT2FIX(0);
+        return INT2FIX(0);
 
     /* fall back */
     return rb_io_fsync(io);
@@ -2719,10 +2907,33 @@ rb_io_pid(VALUE io)
 
     GetOpenFile(io, fptr);
     if (!fptr->pid)
-	return Qnil;
+        return Qnil;
     return PIDT2NUM(fptr->pid);
 }
 
+/*
+ *  call-seq:
+ *    path -> string or nil
+ *
+ *  Returns the path associated with the IO, or +nil+ if there is no path
+ *  associated with the IO. It is not guaranteed that the path exists on
+ *  the filesystem.
+ *
+ *    $stdin.path # => "<STDIN>"
+ *
+ *    File.open("testfile") {|f| f.path} # => "testfile"
+ */
+
+static VALUE
+rb_io_path(VALUE io)
+{
+    rb_io_t *fptr = RFILE(io)->fptr;
+
+    if (!fptr)
+        return Qnil;
+
+    return rb_obj_dup(fptr->pathv);
+}
 
 /*
  *  call-seq:
@@ -2750,16 +2961,16 @@ rb_io_inspect(VALUE obj)
     rb_str_cat2(result, ":");
     if (NIL_P(fptr->pathv)) {
         if (fptr->fd < 0) {
-	    rb_str_cat(result, closed+1, strlen(closed)-1);
+            rb_str_cat(result, closed+1, strlen(closed)-1);
         }
         else {
-	    rb_str_catf(result, "fd %d", fptr->fd);
+            rb_str_catf(result, "fd %d", fptr->fd);
         }
     }
     else {
-	rb_str_append(result, fptr->pathv);
+        rb_str_append(result, fptr->pathv);
         if (fptr->fd < 0) {
-	    rb_str_cat(result, closed, strlen(closed));
+            rb_str_cat(result, closed, strlen(closed));
         }
     }
     return rb_str_cat2(result, ">");
@@ -2805,7 +3016,7 @@ io_bufread(char *ptr, long len, rb_io_t *fptr)
         while (n > 0) {
           again:
             rb_io_check_closed(fptr);
-            c = rb_read_internal(fptr, ptr+offset, n);
+            c = rb_io_read_memory(fptr, ptr+offset, n);
             if (c == 0) break;
             if (c < 0) {
                 if (fptr_wait_readable(fptr))
@@ -2868,27 +3079,27 @@ static long
 remain_size(rb_io_t *fptr)
 {
     struct stat st;
-    off_t siz = READ_DATA_PENDING_COUNT(fptr);
-    off_t pos;
+    rb_off_t siz = READ_DATA_PENDING_COUNT(fptr);
+    rb_off_t pos;
 
     if (fstat(fptr->fd, &st) == 0  && S_ISREG(st.st_mode)
 #if defined(__HAIKU__)
-	&& (st.st_dev > 3)
+        && (st.st_dev > 3)
 #endif
-	)
+        )
     {
         if (io_fflush(fptr) < 0)
             rb_sys_fail_on_write(fptr);
-	pos = lseek(fptr->fd, 0, SEEK_CUR);
-	if (st.st_size >= pos && pos >= 0) {
-	    siz += st.st_size - pos;
-	    if (siz > LONG_MAX) {
-		rb_raise(rb_eIOError, "file too big for single read");
-	    }
-	}
+        pos = lseek(fptr->fd, 0, SEEK_CUR);
+        if (st.st_size >= pos && pos >= 0) {
+            siz += st.st_size - pos;
+            if (siz > LONG_MAX) {
+                rb_raise(rb_eIOError, "file too big for single read");
+            }
+        }
     }
     else {
-	siz += BUFSIZ;
+        siz += BUFSIZ;
     }
     return (long)siz;
 }
@@ -2900,6 +3111,8 @@ io_enc_str(VALUE str, rb_io_t *fptr)
     return str;
 }
 
+static rb_encoding *io_read_encoding(rb_io_t *fptr);
+
 static void
 make_readconv(rb_io_t *fptr, int size)
 {
@@ -2911,7 +3124,7 @@ make_readconv(rb_io_t *fptr, int size)
         ecopts = fptr->encs.ecopts;
         if (fptr->encs.enc2) {
             sname = rb_enc_name(fptr->encs.enc2);
-            dname = rb_enc_name(fptr->encs.enc);
+            dname = rb_enc_name(io_read_encoding(fptr));
         }
         else {
             sname = dname = "";
@@ -2921,7 +3134,7 @@ make_readconv(rb_io_t *fptr, int size)
             rb_exc_raise(rb_econv_open_exc(sname, dname, ecflags));
         fptr->cbuf.off = 0;
         fptr->cbuf.len = 0;
-	if (size < IO_CBUF_CAPA_MIN) size = IO_CBUF_CAPA_MIN;
+        if (size < IO_CBUF_CAPA_MIN) size = IO_CBUF_CAPA_MIN;
         fptr->cbuf.capa = size;
         fptr->cbuf.ptr = ALLOC_N(char, fptr->cbuf.capa);
     }
@@ -2978,27 +3191,27 @@ fill_cbuf(rb_io_t *fptr, int ec_flags)
 
         if (res == econv_finished) {
             return MORE_CHAR_FINISHED;
-	}
+        }
 
         if (res == econv_source_buffer_empty) {
             if (fptr->rbuf.len == 0) {
-		READ_CHECK(fptr);
+                READ_CHECK(fptr);
                 if (io_fillbuf(fptr) < 0) {
-		    if (!fptr->readconv) {
-			return MORE_CHAR_FINISHED;
-		    }
+                    if (!fptr->readconv) {
+                        return MORE_CHAR_FINISHED;
+                    }
                     ds = dp = (unsigned char *)fptr->cbuf.ptr + fptr->cbuf.off + fptr->cbuf.len;
                     de = (unsigned char *)fptr->cbuf.ptr + fptr->cbuf.capa;
                     res = rb_econv_convert(fptr->readconv, NULL, NULL, &dp, de, 0);
                     fptr->cbuf.len += (int)(dp - ds);
                     rb_econv_check_error(fptr->readconv);
-		    break;
+                    break;
                 }
             }
         }
     }
     if (cbuf_len0 != fptr->cbuf.len)
-	return MORE_CHAR_SUSPENDED;
+        return MORE_CHAR_SUSPENDED;
 
     return MORE_CHAR_FINISHED;
 }
@@ -3018,14 +3231,14 @@ io_shift_cbuf(rb_io_t *fptr, int len, VALUE *strp)
 {
     VALUE str = Qnil;
     if (strp) {
-	str = *strp;
-	if (NIL_P(str)) {
-	    *strp = str = rb_str_new(fptr->cbuf.ptr+fptr->cbuf.off, len);
-	}
-	else {
-	    rb_str_cat(str, fptr->cbuf.ptr+fptr->cbuf.off, len);
-	}
-	rb_enc_associate(str, fptr->encs.enc);
+        str = *strp;
+        if (NIL_P(str)) {
+            *strp = str = rb_str_new(fptr->cbuf.ptr+fptr->cbuf.off, len);
+        }
+        else {
+            rb_str_cat(str, fptr->cbuf.ptr+fptr->cbuf.off, len);
+        }
+        rb_enc_associate(str, fptr->encs.enc);
     }
     fptr->cbuf.off += len;
     fptr->cbuf.len -= len;
@@ -3043,22 +3256,25 @@ static int
 io_setstrbuf(VALUE *str, long len)
 {
 #ifdef _WIN32
-    len = (len + 1) & ~1L;	/* round up for wide char */
+    if (len > 0)
+        len = (len + 1) & ~1L;	/* round up for wide char */
 #endif
     if (NIL_P(*str)) {
-	*str = rb_str_new(0, len);
-	return TRUE;
+        *str = rb_str_new(0, len);
+        return TRUE;
     }
     else {
-	VALUE s = StringValue(*str);
-	long clen = RSTRING_LEN(s);
-	if (clen >= len) {
-	    rb_str_modify(s);
-	    return FALSE;
-	}
-	len -= clen;
-    }
-    rb_str_modify_expand(*str, len);
+        VALUE s = StringValue(*str);
+        long clen = RSTRING_LEN(s);
+        if (clen >= len) {
+            rb_str_modify(s);
+            return FALSE;
+        }
+        len -= clen;
+    }
+    if ((rb_str_capacity(*str) - (size_t)RSTRING_LEN(*str)) < (size_t)len) {
+        rb_str_modify_expand(*str, len);
+    }
     return FALSE;
 }
 
@@ -3067,7 +3283,7 @@ static void
 io_shrink_read_string(VALUE str, long n)
 {
     if (rb_str_capacity(str) - n > MAX_REALLOC_GAP) {
-	rb_str_resize(str, n);
+        rb_str_resize(str, n);
     }
 }
 
@@ -3075,9 +3291,9 @@ static void
 io_set_read_length(VALUE str, long n, int shrinkable)
 {
     if (RSTRING_LEN(str) != n) {
-	rb_str_modify(str);
-	rb_str_set_len(str, n);
-	if (shrinkable) io_shrink_read_string(str, n);
+        rb_str_modify(str);
+        rb_str_set_len(str, n);
+        if (shrinkable) io_shrink_read_string(str, n);
     }
 }
 
@@ -3092,28 +3308,28 @@ read_all(rb_io_t *fptr, long siz, VALUE str)
     int shrinkable;
 
     if (NEED_READCONV(fptr)) {
-	int first = !NIL_P(str);
-	SET_BINARY_MODE(fptr);
-	shrinkable = io_setstrbuf(&str,0);
+        int first = !NIL_P(str);
+        SET_BINARY_MODE(fptr);
+        shrinkable = io_setstrbuf(&str,0);
         make_readconv(fptr, 0);
         while (1) {
             VALUE v;
             if (fptr->cbuf.len) {
-		if (first) rb_str_set_len(str, first = 0);
+                if (first) rb_str_set_len(str, first = 0);
                 io_shift_cbuf(fptr, fptr->cbuf.len, &str);
             }
             v = fill_cbuf(fptr, 0);
             if (v != MORE_CHAR_SUSPENDED && v != MORE_CHAR_FINISHED) {
                 if (fptr->cbuf.len) {
-		    if (first) rb_str_set_len(str, first = 0);
+                    if (first) rb_str_set_len(str, first = 0);
                     io_shift_cbuf(fptr, fptr->cbuf.len, &str);
                 }
                 rb_exc_raise(v);
             }
             if (v == MORE_CHAR_FINISHED) {
                 clear_readconv(fptr);
-		if (first) rb_str_set_len(str, first = 0);
-		if (shrinkable) io_shrink_read_string(str, RSTRING_LEN(str));
+                if (first) rb_str_set_len(str, first = 0);
+                if (shrinkable) io_shrink_read_string(str, RSTRING_LEN(str));
                 return io_enc_str(str, fptr);
             }
         }
@@ -3129,19 +3345,29 @@ read_all(rb_io_t *fptr, long siz, VALUE str)
     if (siz == 0) siz = BUFSIZ;
     shrinkable = io_setstrbuf(&str, siz);
     for (;;) {
-	READ_CHECK(fptr);
-	n = io_fread(str, bytes, siz - bytes, fptr);
-	if (n == 0 && bytes == 0) {
-	    rb_str_set_len(str, 0);
-	    break;
-	}
-	bytes += n;
-	rb_str_set_len(str, bytes);
-	if (cr != ENC_CODERANGE_BROKEN)
-	    pos += rb_str_coderange_scan_restartable(RSTRING_PTR(str) + pos, RSTRING_PTR(str) + bytes, enc, &cr);
-	if (bytes < siz) break;
-	siz += BUFSIZ;
-	rb_str_modify_expand(str, BUFSIZ);
+        READ_CHECK(fptr);
+        n = io_fread(str, bytes, siz - bytes, fptr);
+        if (n == 0 && bytes == 0) {
+            rb_str_set_len(str, 0);
+            break;
+        }
+        bytes += n;
+        rb_str_set_len(str, bytes);
+        if (cr != ENC_CODERANGE_BROKEN)
+            pos += rb_str_coderange_scan_restartable(RSTRING_PTR(str) + pos, RSTRING_PTR(str) + bytes, enc, &cr);
+        if (bytes < siz) break;
+        siz += BUFSIZ;
+
+        size_t capa = rb_str_capacity(str);
+        if (capa < (size_t)RSTRING_LEN(str) + BUFSIZ) {
+            if (capa < BUFSIZ) {
+                capa = BUFSIZ;
+            }
+            else if (capa > IO_MAX_BUFFER_GROWTH) {
+                capa = IO_MAX_BUFFER_GROWTH;
+            }
+            rb_str_modify_expand(str, capa);
+        }
     }
     if (shrinkable) io_shrink_read_string(str, RSTRING_LEN(str));
     str = io_enc_str(str, fptr);
@@ -3153,12 +3379,12 @@ void
 rb_io_set_nonblock(rb_io_t *fptr)
 {
     if (rb_fd_set_nonblock(fptr->fd) != 0) {
-	rb_sys_fail_path(fptr->pathv);
+        rb_sys_fail_path(fptr->pathv);
     }
 }
 
 static VALUE
-read_internal_call(VALUE arg)
+io_read_memory_call(VALUE arg)
 {
     struct io_internal_read_struct *iis = (struct io_internal_read_struct *)arg;
 
@@ -3166,7 +3392,7 @@ read_internal_call(VALUE arg)
     if (scheduler != Qnil) {
         VALUE result = rb_fiber_scheduler_io_read_memory(scheduler, iis->fptr->self, iis->buf, iis->capa, 0);
 
-        if (result != Qundef) {
+        if (!UNDEF_P(result)) {
             // This is actually returned as a pseudo-VALUE and later cast to a long:
             return (VALUE)rb_fiber_scheduler_io_result_apply(result);
         }
@@ -3176,9 +3402,9 @@ read_internal_call(VALUE arg)
 }
 
 static long
-read_internal_locktmp(VALUE str, struct io_internal_read_struct *iis)
+io_read_memory_locktmp(VALUE str, struct io_internal_read_struct *iis)
 {
-    return (long)rb_str_locktmp_ensure(str, read_internal_call, (VALUE)iis);
+    return (long)rb_str_locktmp_ensure(str, io_read_memory_call, (VALUE)iis);
 }
 
 #define no_exception_p(opts) !rb_opts_exception_p((opts), TRUE)
@@ -3195,7 +3421,7 @@ io_getpartial(int argc, VALUE *argv, VALUE io, int no_exception, int nonblock)
     rb_scan_args(argc, argv, "11", &length, &str);
 
     if ((len = NUM2LONG(length)) < 0) {
-	rb_raise(rb_eArgError, "negative length %ld given", len);
+        rb_raise(rb_eArgError, "negative length %ld given", len);
     }
 
     shrinkable = io_setstrbuf(&str, len);
@@ -3204,8 +3430,8 @@ io_getpartial(int argc, VALUE *argv, VALUE io, int no_exception, int nonblock)
     rb_io_check_byte_readable(fptr);
 
     if (len == 0) {
-	io_set_read_length(str, 0, shrinkable);
-	return str;
+        io_set_read_length(str, 0, shrinkable);
+        return str;
     }
 
     if (!nonblock)
@@ -3216,23 +3442,25 @@ io_getpartial(int argc, VALUE *argv, VALUE io, int no_exception, int nonblock)
         if (nonblock) {
             rb_io_set_nonblock(fptr);
         }
-	io_setstrbuf(&str, len);
+        io_setstrbuf(&str, len);
         iis.th = rb_thread_current();
         iis.fptr = fptr;
         iis.nonblock = nonblock;
+        iis.fd = fptr->fd;
         iis.buf = RSTRING_PTR(str);
         iis.capa = len;
-        n = read_internal_locktmp(str, &iis);
+        iis.timeout = NULL;
+        n = io_read_memory_locktmp(str, &iis);
         if (n < 0) {
-	    int e = errno;
+            int e = errno;
             if (!nonblock && fptr_wait_readable(fptr))
                 goto again;
-	    if (nonblock && (io_again_p(e))) {
+            if (nonblock && (io_again_p(e))) {
                 if (no_exception)
                     return sym_wait_readable;
                 else
-		    rb_readwrite_syserr_fail(RB_IO_WAIT_READABLE,
-					     e, "read would block");
+                    rb_readwrite_syserr_fail(RB_IO_WAIT_READABLE,
+                                             e, "read would block");
             }
             rb_syserr_fail_path(e, fptr->pathv);
         }
@@ -3367,35 +3595,37 @@ io_read_nonblock(rb_execution_context_t *ec, VALUE io, VALUE length, VALUE str,
     int shrinkable;
 
     if ((len = NUM2LONG(length)) < 0) {
-	rb_raise(rb_eArgError, "negative length %ld given", len);
+        rb_raise(rb_eArgError, "negative length %ld given", len);
     }
 
     shrinkable = io_setstrbuf(&str, len);
-    rb_bool_expected(ex, "exception");
+    rb_bool_expected(ex, "exception", TRUE);
 
     GetOpenFile(io, fptr);
     rb_io_check_byte_readable(fptr);
 
     if (len == 0) {
-	io_set_read_length(str, 0, shrinkable);
-	return str;
+        io_set_read_length(str, 0, shrinkable);
+        return str;
     }
 
     n = read_buffered_data(RSTRING_PTR(str), len, fptr);
     if (n <= 0) {
-	rb_io_set_nonblock(fptr);
-	shrinkable |= io_setstrbuf(&str, len);
+        rb_fd_set_nonblock(fptr->fd);
+        shrinkable |= io_setstrbuf(&str, len);
         iis.fptr = fptr;
         iis.nonblock = 1;
+        iis.fd = fptr->fd;
         iis.buf = RSTRING_PTR(str);
         iis.capa = len;
-        n = read_internal_locktmp(str, &iis);
+        iis.timeout = NULL;
+        n = io_read_memory_locktmp(str, &iis);
         if (n < 0) {
-	    int e = errno;
-	    if (io_again_p(e)) {
+            int e = errno;
+            if (io_again_p(e)) {
                 if (!ex) return sym_wait_readable;
-		rb_readwrite_syserr_fail(RB_IO_WAIT_READABLE,
-					 e, "read would block");
+                rb_readwrite_syserr_fail(RB_IO_WAIT_READABLE,
+                                         e, "read would block");
             }
             rb_syserr_fail_path(e, fptr->pathv);
         }
@@ -3404,7 +3634,7 @@ io_read_nonblock(rb_execution_context_t *ec, VALUE io, VALUE length, VALUE str,
 
     if (n == 0) {
         if (!ex) return Qnil;
-	rb_eof_error();
+        rb_eof_error();
     }
 
     return str;
@@ -3418,8 +3648,8 @@ io_write_nonblock(rb_execution_context_t *ec, VALUE io, VALUE str, VALUE ex)
     long n;
 
     if (!RB_TYPE_P(str, T_STRING))
-	str = rb_obj_as_string(str);
-    rb_bool_expected(ex, "exception");
+        str = rb_obj_as_string(str);
+    rb_bool_expected(ex, "exception", TRUE);
 
     io = GetWriteIO(io);
     GetOpenFile(io, fptr);
@@ -3428,21 +3658,21 @@ io_write_nonblock(rb_execution_context_t *ec, VALUE io, VALUE str, VALUE ex)
     if (io_fflush(fptr) < 0)
         rb_sys_fail_on_write(fptr);
 
-    rb_io_set_nonblock(fptr);
+    rb_fd_set_nonblock(fptr->fd);
     n = write(fptr->fd, RSTRING_PTR(str), RSTRING_LEN(str));
     RB_GC_GUARD(str);
 
     if (n < 0) {
-	int e = errno;
-	if (io_again_p(e)) {
+        int e = errno;
+        if (io_again_p(e)) {
             if (!ex) {
-		return sym_wait_writable;
-	    }
-	    else {
-		rb_readwrite_syserr_fail(RB_IO_WAIT_WRITABLE, e, "write would block");
-	    }
-	}
-	rb_syserr_fail_path(e, fptr->pathv);
+                return sym_wait_writable;
+            }
+            else {
+                rb_readwrite_syserr_fail(RB_IO_WAIT_WRITABLE, e, "write would block");
+            }
+        }
+        rb_syserr_fail_path(e, fptr->pathv);
     }
 
     return LONG2FIX(n);
@@ -3450,14 +3680,13 @@ io_write_nonblock(rb_execution_context_t *ec, VALUE io, VALUE str, VALUE ex)
 
 /*
  *  call-seq:
- *    read(maxlen = nil)             -> string or nil
- *    read(maxlen = nil, out_string) -> out_string or nil
+ *    read(maxlen = nil, out_string = nil) -> new_string, out_string, or nil
  *
- *  Reads bytes from the stream (in binary mode):
+ *  Reads bytes from the stream; the stream must be opened for reading
+ *  (see {Access Modes}[rdoc-ref:File@Access+Modes]):
  *
- *  - If +maxlen+ is +nil+, reads all bytes.
- *  - Otherwise reads +maxlen+ bytes, if available.
- *  - Otherwise reads all bytes.
+ *  - If +maxlen+ is +nil+, reads all bytes using the stream's data mode.
+ *  - Otherwise reads up to +maxlen+ bytes in binary mode.
  *
  *  Returns a string (either a new string or the given +out_string+)
  *  containing the bytes read.
@@ -3517,6 +3746,7 @@ io_write_nonblock(rb_execution_context_t *ec, VALUE io, VALUE str, VALUE ex)
  *  If you need the behavior like a single read(2) system call,
  *  consider #readpartial, #read_nonblock, and #sysread.
  *
+ *  Related: IO#write.
  */
 
 static VALUE
@@ -3533,13 +3763,13 @@ io_read(int argc, VALUE *argv, VALUE io)
     rb_scan_args(argc, argv, "02", &length, &str);
 
     if (NIL_P(length)) {
-	GetOpenFile(io, fptr);
-	rb_io_check_char_readable(fptr);
-	return read_all(fptr, remain_size(fptr), str);
+        GetOpenFile(io, fptr);
+        rb_io_check_char_readable(fptr);
+        return read_all(fptr, remain_size(fptr), str);
     }
     len = NUM2LONG(length);
     if (len < 0) {
-	rb_raise(rb_eArgError, "negative length %ld given", len);
+        rb_raise(rb_eArgError, "negative length %ld given", len);
     }
 
     shrinkable = io_setstrbuf(&str,len);
@@ -3547,8 +3777,8 @@ io_read(int argc, VALUE *argv, VALUE io)
     GetOpenFile(io, fptr);
     rb_io_check_byte_readable(fptr);
     if (len == 0) {
-	io_set_read_length(str, 0, shrinkable);
-	return str;
+        io_set_read_length(str, 0, shrinkable);
+        return str;
     }
 
     READ_CHECK(fptr);
@@ -3559,7 +3789,7 @@ io_read(int argc, VALUE *argv, VALUE io)
     io_set_read_length(str, n, shrinkable);
 #if RUBY_CRLF_ENVIRONMENT
     if (previous_mode == O_TEXT) {
-	setmode(fptr->fd, O_TEXT);
+        setmode(fptr->fd, O_TEXT);
     }
 #endif
     if (n == 0) return Qnil;
@@ -3572,17 +3802,42 @@ rscheck(const char *rsptr, long rslen, VALUE rs)
 {
     if (!rs) return;
     if (RSTRING_PTR(rs) != rsptr && RSTRING_LEN(rs) != rslen)
-	rb_raise(rb_eRuntimeError, "rs modified");
+        rb_raise(rb_eRuntimeError, "rs modified");
+}
+
+static const char *
+search_delim(const char *p, long len, int delim, rb_encoding *enc)
+{
+    if (rb_enc_mbminlen(enc) == 1) {
+        p = memchr(p, delim, len);
+        if (p) return p + 1;
+    }
+    else {
+        const char *end = p + len;
+        while (p < end) {
+            int r = rb_enc_precise_mbclen(p, end, enc);
+            if (!MBCLEN_CHARFOUND_P(r)) {
+                p += rb_enc_mbminlen(enc);
+                continue;
+            }
+            int n = MBCLEN_CHARFOUND_LEN(r);
+            if (rb_enc_mbc_to_codepoint(p, end, enc) == (unsigned int)delim) {
+                return p + n;
+            }
+            p += n;
+        }
+    }
+    return NULL;
 }
 
 static int
-appendline(rb_io_t *fptr, int delim, VALUE *strp, long *lp)
+appendline(rb_io_t *fptr, int delim, VALUE *strp, long *lp, rb_encoding *enc)
 {
     VALUE str = *strp;
     long limit = *lp;
 
     if (NEED_READCONV(fptr)) {
-	SET_BINARY_MODE(fptr);
+        SET_BINARY_MODE(fptr);
         make_readconv(fptr, 0);
         do {
             const char *p, *e;
@@ -3591,9 +3846,9 @@ appendline(rb_io_t *fptr, int delim, VALUE *strp, long *lp)
                 p = READ_CHAR_PENDING_PTR(fptr);
                 if (0 < limit && limit < searchlen)
                     searchlen = (int)limit;
-                e = memchr(p, delim, searchlen);
+                e = search_delim(p, searchlen, delim, enc);
                 if (e) {
-		    int len = (int)(e-p+1);
+                    int len = (int)(e-p);
                     if (NIL_P(str))
                         *strp = str = rb_str_new(p, len);
                     else
@@ -3626,32 +3881,32 @@ appendline(rb_io_t *fptr, int delim, VALUE *strp, long *lp)
 
     NEED_NEWLINE_DECORATOR_ON_READ_CHECK(fptr);
     do {
-	long pending = READ_DATA_PENDING_COUNT(fptr);
-	if (pending > 0) {
-	    const char *p = READ_DATA_PENDING_PTR(fptr);
-	    const char *e;
-	    long last;
-
-	    if (limit > 0 && pending > limit) pending = limit;
-	    e = memchr(p, delim, pending);
-	    if (e) pending = e - p + 1;
-	    if (!NIL_P(str)) {
-		last = RSTRING_LEN(str);
-		rb_str_resize(str, last + pending);
-	    }
-	    else {
+        long pending = READ_DATA_PENDING_COUNT(fptr);
+        if (pending > 0) {
+            const char *p = READ_DATA_PENDING_PTR(fptr);
+            const char *e;
+            long last;
+
+            if (limit > 0 && pending > limit) pending = limit;
+            e = search_delim(p, pending, delim, enc);
+            if (e) pending = e - p;
+            if (!NIL_P(str)) {
+                last = RSTRING_LEN(str);
+                rb_str_resize(str, last + pending);
+            }
+            else {
                 last = 0;
-		*strp = str = rb_str_buf_new(pending);
-		rb_str_set_len(str, pending);
-	    }
-	    read_buffered_data(RSTRING_PTR(str) + last, pending, fptr); /* must not fail */
-	    limit -= pending;
-	    *lp = limit;
-	    if (e) return delim;
-	    if (limit == 0)
-		return (unsigned char)RSTRING_PTR(str)[RSTRING_LEN(str)-1];
-	}
-	READ_CHECK(fptr);
+                *strp = str = rb_str_buf_new(pending);
+                rb_str_set_len(str, pending);
+            }
+            read_buffered_data(RSTRING_PTR(str) + last, pending, fptr); /* must not fail */
+            limit -= pending;
+            *lp = limit;
+            if (e) return delim;
+            if (limit == 0)
+                return (unsigned char)RSTRING_PTR(str)[RSTRING_LEN(str)-1];
+        }
+        READ_CHECK(fptr);
     } while (io_fillbuf(fptr) >= 0);
     *lp = limit;
     return EOF;
@@ -3661,47 +3916,47 @@ static inline int
 swallow(rb_io_t *fptr, int term)
 {
     if (NEED_READCONV(fptr)) {
-	rb_encoding *enc = io_read_encoding(fptr);
-	int needconv = rb_enc_mbminlen(enc) != 1;
-	SET_BINARY_MODE(fptr);
-	make_readconv(fptr, 0);
-	do {
-	    size_t cnt;
-	    while ((cnt = READ_CHAR_PENDING_COUNT(fptr)) > 0) {
-		const char *p = READ_CHAR_PENDING_PTR(fptr);
-		int i;
-		if (!needconv) {
-		    if (*p != term) return TRUE;
-		    i = (int)cnt;
-		    while (--i && *++p == term);
-		}
-		else {
-		    const char *e = p + cnt;
-		    if (rb_enc_ascget(p, e, &i, enc) != term) return TRUE;
-		    while ((p += i) < e && rb_enc_ascget(p, e, &i, enc) == term);
-		    i = (int)(e - p);
-		}
-		io_shift_cbuf(fptr, (int)cnt - i, NULL);
-	    }
-	} while (more_char(fptr) != MORE_CHAR_FINISHED);
-	return FALSE;
+        rb_encoding *enc = io_read_encoding(fptr);
+        int needconv = rb_enc_mbminlen(enc) != 1;
+        SET_BINARY_MODE(fptr);
+        make_readconv(fptr, 0);
+        do {
+            size_t cnt;
+            while ((cnt = READ_CHAR_PENDING_COUNT(fptr)) > 0) {
+                const char *p = READ_CHAR_PENDING_PTR(fptr);
+                int i;
+                if (!needconv) {
+                    if (*p != term) return TRUE;
+                    i = (int)cnt;
+                    while (--i && *++p == term);
+                }
+                else {
+                    const char *e = p + cnt;
+                    if (rb_enc_ascget(p, e, &i, enc) != term) return TRUE;
+                    while ((p += i) < e && rb_enc_ascget(p, e, &i, enc) == term);
+                    i = (int)(e - p);
+                }
+                io_shift_cbuf(fptr, (int)cnt - i, NULL);
+            }
+        } while (more_char(fptr) != MORE_CHAR_FINISHED);
+        return FALSE;
     }
 
     NEED_NEWLINE_DECORATOR_ON_READ_CHECK(fptr);
     do {
-	size_t cnt;
-	while ((cnt = READ_DATA_PENDING_COUNT(fptr)) > 0) {
-	    char buf[1024];
-	    const char *p = READ_DATA_PENDING_PTR(fptr);
-	    int i;
-	    if (cnt > sizeof buf) cnt = sizeof buf;
-	    if (*p != term) return TRUE;
-	    i = (int)cnt;
-	    while (--i && *++p == term);
-	    if (!read_buffered_data(buf, cnt - i, fptr)) /* must not fail */
-		rb_sys_fail_path(fptr->pathv);
-	}
-	READ_CHECK(fptr);
+        size_t cnt;
+        while ((cnt = READ_DATA_PENDING_COUNT(fptr)) > 0) {
+            char buf[1024];
+            const char *p = READ_DATA_PENDING_PTR(fptr);
+            int i;
+            if (cnt > sizeof buf) cnt = sizeof buf;
+            if (*p != term) return TRUE;
+            i = (int)cnt;
+            while (--i && *++p == term);
+            if (!read_buffered_data(buf, cnt - i, fptr)) /* must not fail */
+                rb_sys_fail_path(fptr->pathv);
+        }
+        READ_CHECK(fptr);
     } while (io_fillbuf(fptr) == 0);
     return FALSE;
 }
@@ -3715,43 +3970,43 @@ rb_io_getline_fast(rb_io_t *fptr, rb_encoding *enc, int chomp)
     int cr = 0;
 
     do {
-	int pending = READ_DATA_PENDING_COUNT(fptr);
+        int pending = READ_DATA_PENDING_COUNT(fptr);
 
-	if (pending > 0) {
-	    const char *p = READ_DATA_PENDING_PTR(fptr);
-	    const char *e;
-	    int chomplen = 0;
+        if (pending > 0) {
+            const char *p = READ_DATA_PENDING_PTR(fptr);
+            const char *e;
+            int chomplen = 0;
 
-	    e = memchr(p, '\n', pending);
-	    if (e) {
+            e = memchr(p, '\n', pending);
+            if (e) {
                 pending = (int)(e - p + 1);
-		if (chomp) {
-		    chomplen = (pending > 1 && *(e-1) == '\r') + 1;
-		}
-	    }
-	    if (NIL_P(str)) {
-		str = rb_str_new(p, pending - chomplen);
-		fptr->rbuf.off += pending;
-		fptr->rbuf.len -= pending;
-	    }
-	    else {
-		rb_str_resize(str, len + pending - chomplen);
-		read_buffered_data(RSTRING_PTR(str)+len, pending - chomplen, fptr);
-		fptr->rbuf.off += chomplen;
-		fptr->rbuf.len -= chomplen;
+                if (chomp) {
+                    chomplen = (pending > 1 && *(e-1) == '\r') + 1;
+                }
+            }
+            if (NIL_P(str)) {
+                str = rb_str_new(p, pending - chomplen);
+                fptr->rbuf.off += pending;
+                fptr->rbuf.len -= pending;
+            }
+            else {
+                rb_str_resize(str, len + pending - chomplen);
+                read_buffered_data(RSTRING_PTR(str)+len, pending - chomplen, fptr);
+                fptr->rbuf.off += chomplen;
+                fptr->rbuf.len -= chomplen;
                 if (pending == 1 && chomplen == 1 && len > 0) {
                     if (RSTRING_PTR(str)[len-1] == '\r') {
                         rb_str_resize(str, --len);
                         break;
                     }
                 }
-	    }
-	    len += pending - chomplen;
-	    if (cr != ENC_CODERANGE_BROKEN)
-		pos += rb_str_coderange_scan_restartable(RSTRING_PTR(str) + pos, RSTRING_PTR(str) + len, enc, &cr);
-	    if (e) break;
-	}
-	READ_CHECK(fptr);
+            }
+            len += pending - chomplen;
+            if (cr != ENC_CODERANGE_BROKEN)
+                pos += rb_str_coderange_scan_restartable(RSTRING_PTR(str) + pos, RSTRING_PTR(str) + len, enc, &cr);
+            if (e) break;
+        }
+        READ_CHECK(fptr);
     } while (io_fillbuf(fptr) >= 0);
     if (NIL_P(str)) return Qnil;
 
@@ -3774,13 +4029,13 @@ extract_getline_opts(VALUE opts, struct getline_arg *args)
 {
     int chomp = FALSE;
     if (!NIL_P(opts)) {
-	static ID kwds[1];
-	VALUE vchomp;
-	if (!kwds[0]) {
-	    kwds[0] = rb_intern_const("chomp");
-	}
-	rb_get_kwargs(opts, kwds, 0, -2, &vchomp);
-	chomp = (vchomp != Qundef) && RTEST(vchomp);
+        static ID kwds[1];
+        VALUE vchomp;
+        if (!kwds[0]) {
+            kwds[0] = rb_intern_const("chomp");
+        }
+        rb_get_kwargs(opts, kwds, 0, -2, &vchomp);
+        chomp = (!UNDEF_P(vchomp)) && RTEST(vchomp);
     }
     args->chomp = chomp;
 }
@@ -3801,7 +4056,7 @@ extract_getline_args(int argc, VALUE *argv, struct getline_arg *args)
         }
     }
     else if (2 <= argc) {
-	rs = argv[0], lim = argv[1];
+        rs = argv[0], lim = argv[1];
         if (!NIL_P(rs))
             StringValue(rs);
     }
@@ -3816,25 +4071,25 @@ check_getline_args(VALUE *rsp, long *limit, VALUE io)
     VALUE rs = *rsp;
 
     if (!NIL_P(rs)) {
-	rb_encoding *enc_rs, *enc_io;
-
-	GetOpenFile(io, fptr);
-	enc_rs = rb_enc_get(rs);
-	enc_io = io_read_encoding(fptr);
-	if (enc_io != enc_rs &&
-	    (rb_enc_str_coderange(rs) != ENC_CODERANGE_7BIT ||
-	     (RSTRING_LEN(rs) > 0 && !rb_enc_asciicompat(enc_io)))) {
+        rb_encoding *enc_rs, *enc_io;
+
+        GetOpenFile(io, fptr);
+        enc_rs = rb_enc_get(rs);
+        enc_io = io_read_encoding(fptr);
+        if (enc_io != enc_rs &&
+            (!is_ascii_string(rs) ||
+             (RSTRING_LEN(rs) > 0 && !rb_enc_asciicompat(enc_io)))) {
             if (rs == rb_default_rs) {
                 rs = rb_enc_str_new(0, 0, enc_io);
                 rb_str_buf_cat_ascii(rs, "\n");
-		*rsp = rs;
+                *rsp = rs;
             }
             else {
                 rb_raise(rb_eArgError, "encoding mismatch: %s IO with %s RS",
                          rb_enc_name(enc_io),
                          rb_enc_name(enc_rs));
             }
-	}
+        }
     }
 }
 
@@ -3857,77 +4112,86 @@ rb_io_getline_0(VALUE rs, long limit, int chomp, rb_io_t *fptr)
 
     rb_io_check_char_readable(fptr);
     if (NIL_P(rs) && limit < 0) {
-	str = read_all(fptr, 0, Qnil);
-	if (RSTRING_LEN(str) == 0) return Qnil;
-	if (chomp) rb_str_chomp_string(str, rb_default_rs);
+        str = read_all(fptr, 0, Qnil);
+        if (RSTRING_LEN(str) == 0) return Qnil;
     }
     else if (limit == 0) {
-	return rb_enc_str_new(0, 0, io_read_encoding(fptr));
+        return rb_enc_str_new(0, 0, io_read_encoding(fptr));
     }
     else if (rs == rb_default_rs && limit < 0 && !NEED_READCONV(fptr) &&
              rb_enc_asciicompat(enc = io_read_encoding(fptr))) {
-	NEED_NEWLINE_DECORATOR_ON_READ_CHECK(fptr);
-	return rb_io_getline_fast(fptr, enc, chomp);
+        NEED_NEWLINE_DECORATOR_ON_READ_CHECK(fptr);
+        return rb_io_getline_fast(fptr, enc, chomp);
     }
     else {
-	int c, newline = -1;
-	const char *rsptr = 0;
-	long rslen = 0;
-	int rspara = 0;
+        int c, newline = -1;
+        const char *rsptr = 0;
+        long rslen = 0;
+        int rspara = 0;
         int extra_limit = 16;
-	int chomp_cr = chomp;
+        int chomp_cr = chomp;
 
-	SET_BINARY_MODE(fptr);
+        SET_BINARY_MODE(fptr);
         enc = io_read_encoding(fptr);
 
-	if (!NIL_P(rs)) {
-	    rslen = RSTRING_LEN(rs);
-	    if (rslen == 0) {
-		rsptr = "\n\n";
-		rslen = 2;
-		rspara = 1;
-		swallow(fptr, '\n');
-		rs = 0;
-		if (!rb_enc_asciicompat(enc)) {
-		    rs = rb_usascii_str_new(rsptr, rslen);
-		    rs = rb_str_encode(rs, rb_enc_from_encoding(enc), 0, Qnil);
-		    OBJ_FREEZE(rs);
-		    rsptr = RSTRING_PTR(rs);
-		    rslen = RSTRING_LEN(rs);
-		}
-	    }
-	    else {
-		rsptr = RSTRING_PTR(rs);
-	    }
-	    newline = (unsigned char)rsptr[rslen - 1];
-	    chomp_cr = chomp && rslen == 1 && newline == '\n';
-	}
-
-	/* MS - Optimization */
-	while ((c = appendline(fptr, newline, &str, &limit)) != EOF) {
+        if (!NIL_P(rs)) {
+            rslen = RSTRING_LEN(rs);
+            if (rslen == 0) {
+                rsptr = "\n\n";
+                rslen = 2;
+                rspara = 1;
+                swallow(fptr, '\n');
+                rs = 0;
+                if (!rb_enc_asciicompat(enc)) {
+                    rs = rb_usascii_str_new(rsptr, rslen);
+                    rs = rb_str_encode(rs, rb_enc_from_encoding(enc), 0, Qnil);
+                    OBJ_FREEZE(rs);
+                    rsptr = RSTRING_PTR(rs);
+                    rslen = RSTRING_LEN(rs);
+                }
+                newline = '\n';
+            }
+            else if (rb_enc_mbminlen(enc) == 1) {
+                 rsptr = RSTRING_PTR(rs);
+                 newline = (unsigned char)rsptr[rslen - 1];
+            }
+            else {
+                rs = rb_str_encode(rs, rb_enc_from_encoding(enc), 0, Qnil);
+                rsptr = RSTRING_PTR(rs);
+                const char *e = rsptr + rslen;
+                const char *last = rb_enc_prev_char(rsptr, e, e, enc);
+                int n;
+                newline = rb_enc_codepoint_len(last, e, &n, enc);
+                if (last + n != e) rb_raise(rb_eArgError, "broken separator");
+            }
+            chomp_cr = chomp && newline == '\n' && rslen == rb_enc_mbminlen(enc);
+        }
+
+        /* MS - Optimization */
+        while ((c = appendline(fptr, newline, &str, &limit, enc)) != EOF) {
             const char *s, *p, *pp, *e;
 
-	    if (c == newline) {
-		if (RSTRING_LEN(str) < rslen) continue;
-		s = RSTRING_PTR(str);
+            if (c == newline) {
+                if (RSTRING_LEN(str) < rslen) continue;
+                s = RSTRING_PTR(str);
                 e = RSTRING_END(str);
-		p = e - rslen;
-		pp = rb_enc_left_char_head(s, p, e, enc);
-		if (pp != p) continue;
-		if (!rspara) rscheck(rsptr, rslen, rs);
-		if (memcmp(p, rsptr, rslen) == 0) {
-		    if (chomp) {
-			if (chomp_cr && p > s && *(p-1) == '\r') --p;
-			rb_str_set_len(str, p - s);
-		    }
-		    break;
-		}
-	    }
-	    if (limit == 0) {
-		s = RSTRING_PTR(str);
-		p = RSTRING_END(str);
-		pp = rb_enc_left_char_head(s, p-1, p, enc);
-                if (extra_limit &&
+                p = e - rslen;
+                pp = rb_enc_left_char_head(s, p, e, enc);
+                if (pp != p) continue;
+                if (!rspara) rscheck(rsptr, rslen, rs);
+                if (memcmp(p, rsptr, rslen) == 0) {
+                    if (chomp) {
+                        if (chomp_cr && p > s && *(p-1) == '\r') --p;
+                        rb_str_set_len(str, p - s);
+                    }
+                    break;
+                }
+            }
+            if (limit == 0) {
+                s = RSTRING_PTR(str);
+                p = RSTRING_END(str);
+                pp = rb_enc_prev_char(s, p, p, enc);
+                if (extra_limit && pp &&
                     MBCLEN_NEEDMORE_P(rb_enc_precise_mbclen(pp, p, enc))) {
                     /* relax the limit while incomplete character.
                      * extra_limit limits the relax length */
@@ -3938,17 +4202,17 @@ rb_io_getline_0(VALUE rs, long limit, int chomp, rb_io_t *fptr)
                     nolimit = 1;
                     break;
                 }
-	    }
-	}
+            }
+        }
 
-	if (rspara && c != EOF)
-	    swallow(fptr, '\n');
-	if (!NIL_P(str))
+        if (rspara && c != EOF)
+            swallow(fptr, '\n');
+        if (!NIL_P(str))
             str = io_enc_str(str, fptr);
     }
 
     if (!NIL_P(str) && !nolimit) {
-	fptr->lineno++;
+        fptr->lineno++;
     }
 
     return str;
@@ -3965,13 +4229,13 @@ rb_io_getline_1(VALUE rs, long limit, int chomp, VALUE io)
     old_lineno = fptr->lineno;
     str = rb_io_getline_0(rs, limit, chomp, fptr);
     if (!NIL_P(str) && (new_lineno = fptr->lineno) != old_lineno) {
-	if (io == ARGF.current_file) {
-	    ARGF.lineno += new_lineno - old_lineno;
-	    ARGF.last_lineno = ARGF.lineno;
-	}
-	else {
-	    ARGF.last_lineno = new_lineno;
-	}
+        if (io == ARGF.current_file) {
+            ARGF.lineno += new_lineno - old_lineno;
+            ARGF.last_lineno = ARGF.lineno;
+        }
+        else {
+            ARGF.last_lineno = new_lineno;
+        }
     }
 
     return str;
@@ -4002,13 +4266,13 @@ rb_io_gets_internal(VALUE io)
 
 /*
  *  call-seq:
- *    gets(sep = $/, **line_opts)   -> string or nil
- *    gets(limit, **line_opts)      -> string or nil
- *    gets(sep, limit, **line_opts) -> string or nil
+ *    gets(sep = $/, chomp: false)   -> string or nil
+ *    gets(limit, chomp: false)      -> string or nil
+ *    gets(sep, limit, chomp: false) -> string or nil
  *
- *  Reads and returns a line from the stream
- *  (see {Lines}[rdoc-ref:IO@Lines]);
+ *  Reads and returns a line from the stream;
  *  assigns the return value to <tt>$_</tt>.
+ *  See {Line IO}[rdoc-ref:IO@Line+IO].
  *
  *  With no arguments given, returns the next line
  *  as determined by line separator <tt>$/</tt>, or +nil+ if none:
@@ -4046,7 +4310,7 @@ rb_io_gets_internal(VALUE io)
  *
  *  With only integer argument +limit+ given,
  *  limits the number of bytes in the line;
- *  see {Line Limit}}[rdoc-ref:IO@Line+Limit]:
+ *  see {Line Limit}[rdoc-ref:IO@Line+Limit]:
  *
  *    # No more than one line.
  *    File.open('t.txt') {|f| f.gets(10) } # => "First line"
@@ -4060,8 +4324,8 @@ rb_io_gets_internal(VALUE io)
  *    or +nil+ if none.
  *  - But returns no more bytes than are allowed by the limit.
  *
- *  For all forms above, optional keyword arguments +line_opts+ specify
- *  {Line Options}[rdoc-ref:IO@Line+Options]:
+ *  Optional keyword argument +chomp+ specifies whether line separators
+ *  are to be omitted:
  *
  *    f = File.open('t.txt')
  *    # Chomp the lines.
@@ -4090,8 +4354,8 @@ rb_io_gets_m(int argc, VALUE *argv, VALUE io)
  *  call-seq:
  *    lineno -> integer
  *
- *  Returns the current line number for the stream.
- *  See {Line Number}[rdoc-ref:IO@Line+Number].
+ *  Returns the current line number for the stream;
+ *  see {Line Number}[rdoc-ref:IO@Line+Number].
  *
  */
 
@@ -4109,8 +4373,8 @@ rb_io_lineno(VALUE io)
  *  call-seq:
  *    lineno = integer -> integer
  *
- *  Sets and returns the line number for the stream.
- *  See {Line Number}[rdoc-ref:IO@Line+Number].
+ *  Sets and returns the line number for the stream;
+ *  see {Line Number}[rdoc-ref:IO@Line+Number].
  *
  */
 
@@ -4127,12 +4391,14 @@ rb_io_set_lineno(VALUE io, VALUE lineno)
 
 /*
  *  call-seq:
- *    readline(sep = $/, **line_opts)   -> string
- *    readline(limit, **line_opts)      -> string
- *    readline(sep, limit, **line_opts) -> string
+ *    readline(sep = $/, chomp: false)   -> string
+ *    readline(limit, chomp: false)      -> string
+ *    readline(sep, limit, chomp: false) -> string
  *
- *  Reads a line as with IO#gets, but raises EOFError if already at end-of-file.
+ *  Reads a line as with IO#gets, but raises EOFError if already at end-of-stream.
  *
+ *  Optional keyword argument +chomp+ specifies whether line separators
+ *  are to be omitted.
  */
 
 static VALUE
@@ -4141,7 +4407,7 @@ rb_io_readline(int argc, VALUE *argv, VALUE io)
     VALUE line = rb_io_gets_m(argc, argv, io);
 
     if (NIL_P(line)) {
-	rb_eof_error();
+        rb_eof_error();
     }
     return line;
 }
@@ -4150,13 +4416,13 @@ static VALUE io_readlines(const struct getline_arg *arg, VALUE io);
 
 /*
  *  call-seq:
- *    readlines(sep = $/, **line_opts)   -> array
- *    readlines(limit, **line_opts)       -> array
- *    readlines(sep, limit, **line_opts) -> array
+ *    readlines(sep = $/, chomp: false)   -> array
+ *    readlines(limit, chomp: false)       -> array
+ *    readlines(sep, limit, chomp: false) -> array
  *
- *  Reads and returns all remaining line from the stream
- *  (see {Lines}[rdoc-ref:IO@Lines]);
+ *  Reads and returns all remaining line from the stream;
  *  does not modify <tt>$_</tt>.
+ *  See {Line IO}[rdoc-ref:IO@Line+IO].
  *
  *  With no arguments given, returns lines
  *  as determined by line separator <tt>$/</tt>, or +nil+ if none:
@@ -4191,7 +4457,7 @@ static VALUE io_readlines(const struct getline_arg *arg, VALUE io);
  *
  *  With only integer argument +limit+ given,
  *  limits the number of bytes in each line;
- *  see {Line Limit}}[rdoc-ref:IO@Line+Limit]:
+ *  see {Line Limit}[rdoc-ref:IO@Line+Limit]:
  *
  *    f = File.new('t.txt')
  *    f.readlines(8)
@@ -4204,8 +4470,8 @@ static VALUE io_readlines(const struct getline_arg *arg, VALUE io);
  *  - Returns lines as determined by line separator +sep+.
  *  - But returns no more bytes in a line than are allowed by the limit.
  *
- *  For all forms above, optional keyword arguments +line_opts+ specify
- *  {Line Options}[rdoc-ref:IO@Line+Options]:
+ *  Optional keyword argument +chomp+ specifies whether line separators
+ *  are to be omitted:
  *
  *    f = File.new('t.txt')
  *    f.readlines(chomp: true)
@@ -4229,25 +4495,25 @@ io_readlines(const struct getline_arg *arg, VALUE io)
     VALUE line, ary;
 
     if (arg->limit == 0)
-	rb_raise(rb_eArgError, "invalid limit: 0 for readlines");
+        rb_raise(rb_eArgError, "invalid limit: 0 for readlines");
     ary = rb_ary_new();
     while (!NIL_P(line = rb_io_getline_1(arg->rs, arg->limit, arg->chomp, io))) {
-	rb_ary_push(ary, line);
+        rb_ary_push(ary, line);
     }
     return ary;
 }
 
 /*
  *  call-seq:
- *    each_line(sep = $/, **line_opts) {|line| ... }   -> self
- *    each_line(limit, **line_opts) {|line| ... }      -> self
- *    each_line(sep, limit, **line_opts) {|line| ... } -> self
+ *    each_line(sep = $/, chomp: false) {|line| ... }   -> self
+ *    each_line(limit, chomp: false) {|line| ... }      -> self
+ *    each_line(sep, limit, chomp: false) {|line| ... } -> self
  *    each_line                                   -> enumerator
  *
- *  Calls the block with each remaining line read from the stream
- *  (see {Lines}[rdoc-ref:IO@Lines]);
- *  does nothing if already at end-of-file;
+ *  Calls the block with each remaining line read from the stream;
  *  returns +self+.
+ *  Does nothing if already at end-of-stream;
+ *  See {Line IO}[rdoc-ref:IO@Line+IO].
  *
  *  With no arguments given, reads lines
  *  as determined by line separator <tt>$/</tt>:
@@ -4303,7 +4569,7 @@ io_readlines(const struct getline_arg *arg, VALUE io)
  *
  *  With only integer argument +limit+ given,
  *  limits the number of bytes in each line;
- *  see {Line Limit}}[rdoc-ref:IO@Line+Limit]:
+ *  see {Line Limit}[rdoc-ref:IO@Line+Limit]:
  *
  *    f = File.new('t.txt')
  *    f.each_line(8) {|line| p line }
@@ -4327,8 +4593,8 @@ io_readlines(const struct getline_arg *arg, VALUE io)
  *  - Calls with the next line as determined by line separator +sep+.
  *  - But returns no more bytes than are allowed by the limit.
  *
- *  For all forms above, optional keyword arguments +line_opts+ specify
- *  {Line Options}[rdoc-ref:IO@Line+Options]:
+ *  Optional keyword argument +chomp+ specifies whether line separators
+ *  are to be omitted:
  *
  *    f = File.new('t.txt')
  *    f.each_line(chomp: true) {|line| p line }
@@ -4357,9 +4623,9 @@ rb_io_each_line(int argc, VALUE *argv, VALUE io)
     RETURN_ENUMERATOR(io, argc, argv);
     prepare_getline_args(argc, argv, &args, io);
     if (args.limit == 0)
-	rb_raise(rb_eArgError, "invalid limit: 0 for each_line");
+        rb_raise(rb_eArgError, "invalid limit: 0 for each_line");
     while (!NIL_P(str = rb_io_getline_1(args.rs, args.limit, args.chomp, io))) {
-	rb_yield(str);
+        rb_yield(str);
     }
     return io;
 }
@@ -4369,7 +4635,8 @@ rb_io_each_line(int argc, VALUE *argv, VALUE io)
  *    each_byte {|byte| ... } -> self
  *    each_byte               -> enumerator
  *
- *  Calls the given block with each byte (0..255) in the stream; returns +self+:
+ *  Calls the given block with each byte (0..255) in the stream; returns +self+.
+ *  See {Byte IO}[rdoc-ref:IO@Byte+IO].
  *
  *    f = File.new('t.rus')
  *    a = []
@@ -4392,14 +4659,14 @@ rb_io_each_byte(VALUE io)
     GetOpenFile(io, fptr);
 
     do {
-	while (fptr->rbuf.len > 0) {
-	    char *p = fptr->rbuf.ptr + fptr->rbuf.off++;
-	    fptr->rbuf.len--;
-	    rb_yield(INT2FIX(*p & 0xff));
-	    rb_io_check_byte_readable(fptr);
-	    errno = 0;
-	}
-	READ_CHECK(fptr);
+        while (fptr->rbuf.len > 0) {
+            char *p = fptr->rbuf.ptr + fptr->rbuf.off++;
+            fptr->rbuf.len--;
+            rb_yield(INT2FIX(*p & 0xff));
+            rb_io_check_byte_readable(fptr);
+            errno = 0;
+        }
+        READ_CHECK(fptr);
     } while (io_fillbuf(fptr) >= 0);
     return io;
 }
@@ -4411,17 +4678,17 @@ io_getc(rb_io_t *fptr, rb_encoding *enc)
     VALUE str;
 
     if (NEED_READCONV(fptr)) {
-	rb_encoding *read_enc = io_read_encoding(fptr);
+        rb_encoding *read_enc = io_read_encoding(fptr);
 
-	str = Qnil;
-	SET_BINARY_MODE(fptr);
+        str = Qnil;
+        SET_BINARY_MODE(fptr);
         make_readconv(fptr, 0);
 
         while (1) {
             if (fptr->cbuf.len) {
-		r = rb_enc_precise_mbclen(fptr->cbuf.ptr+fptr->cbuf.off,
-			fptr->cbuf.ptr+fptr->cbuf.off+fptr->cbuf.len,
-			read_enc);
+                r = rb_enc_precise_mbclen(fptr->cbuf.ptr+fptr->cbuf.off,
+                        fptr->cbuf.ptr+fptr->cbuf.off+fptr->cbuf.len,
+                        read_enc);
                 if (!MBCLEN_NEEDMORE_P(r))
                     break;
                 if (fptr->cbuf.len == fptr->cbuf.capa) {
@@ -4431,16 +4698,16 @@ io_getc(rb_io_t *fptr, rb_encoding *enc)
 
             if (more_char(fptr) == MORE_CHAR_FINISHED) {
                 if (fptr->cbuf.len == 0) {
-		    clear_readconv(fptr);
-		    return Qnil;
-		}
+                    clear_readconv(fptr);
+                    return Qnil;
+                }
                 /* return an unit of an incomplete character just before EOF */
-		str = rb_enc_str_new(fptr->cbuf.ptr+fptr->cbuf.off, 1, read_enc);
-		fptr->cbuf.off += 1;
-		fptr->cbuf.len -= 1;
+                str = rb_enc_str_new(fptr->cbuf.ptr+fptr->cbuf.off, 1, read_enc);
+                fptr->cbuf.off += 1;
+                fptr->cbuf.len -= 1;
                 if (fptr->cbuf.len == 0) clear_readconv(fptr);
-		ENC_CODERANGE_SET(str, ENC_CODERANGE_BROKEN);
-		return str;
+                ENC_CODERANGE_SET(str, ENC_CODERANGE_BROKEN);
+                return str;
             }
         }
         if (MBCLEN_INVALID_P(r)) {
@@ -4448,62 +4715,62 @@ io_getc(rb_io_t *fptr, rb_encoding *enc)
                               fptr->cbuf.ptr+fptr->cbuf.off+fptr->cbuf.len,
                               read_enc);
             io_shift_cbuf(fptr, r, &str);
-	    cr = ENC_CODERANGE_BROKEN;
-	}
-	else {
-	    io_shift_cbuf(fptr, MBCLEN_CHARFOUND_LEN(r), &str);
-	    cr = ENC_CODERANGE_VALID;
-	    if (MBCLEN_CHARFOUND_LEN(r) == 1 && rb_enc_asciicompat(read_enc) &&
-		ISASCII(RSTRING_PTR(str)[0])) {
-		cr = ENC_CODERANGE_7BIT;
-	    }
-	}
-	str = io_enc_str(str, fptr);
-	ENC_CODERANGE_SET(str, cr);
-	return str;
+            cr = ENC_CODERANGE_BROKEN;
+        }
+        else {
+            io_shift_cbuf(fptr, MBCLEN_CHARFOUND_LEN(r), &str);
+            cr = ENC_CODERANGE_VALID;
+            if (MBCLEN_CHARFOUND_LEN(r) == 1 && rb_enc_asciicompat(read_enc) &&
+                ISASCII(RSTRING_PTR(str)[0])) {
+                cr = ENC_CODERANGE_7BIT;
+            }
+        }
+        str = io_enc_str(str, fptr);
+        ENC_CODERANGE_SET(str, cr);
+        return str;
     }
 
     NEED_NEWLINE_DECORATOR_ON_READ_CHECK(fptr);
     if (io_fillbuf(fptr) < 0) {
-	return Qnil;
+        return Qnil;
     }
     if (rb_enc_asciicompat(enc) && ISASCII(fptr->rbuf.ptr[fptr->rbuf.off])) {
-	str = rb_str_new(fptr->rbuf.ptr+fptr->rbuf.off, 1);
-	fptr->rbuf.off += 1;
-	fptr->rbuf.len -= 1;
-	cr = ENC_CODERANGE_7BIT;
+        str = rb_str_new(fptr->rbuf.ptr+fptr->rbuf.off, 1);
+        fptr->rbuf.off += 1;
+        fptr->rbuf.len -= 1;
+        cr = ENC_CODERANGE_7BIT;
     }
     else {
-	r = rb_enc_precise_mbclen(fptr->rbuf.ptr+fptr->rbuf.off, fptr->rbuf.ptr+fptr->rbuf.off+fptr->rbuf.len, enc);
-	if (MBCLEN_CHARFOUND_P(r) &&
-	    (n = MBCLEN_CHARFOUND_LEN(r)) <= fptr->rbuf.len) {
-	    str = rb_str_new(fptr->rbuf.ptr+fptr->rbuf.off, n);
-	    fptr->rbuf.off += n;
-	    fptr->rbuf.len -= n;
-	    cr = ENC_CODERANGE_VALID;
-	}
-	else if (MBCLEN_NEEDMORE_P(r)) {
-	    str = rb_str_new(fptr->rbuf.ptr+fptr->rbuf.off, fptr->rbuf.len);
-	    fptr->rbuf.len = 0;
-	  getc_needmore:
-	    if (io_fillbuf(fptr) != -1) {
-		rb_str_cat(str, fptr->rbuf.ptr+fptr->rbuf.off, 1);
-		fptr->rbuf.off++;
-		fptr->rbuf.len--;
-		r = rb_enc_precise_mbclen(RSTRING_PTR(str), RSTRING_PTR(str)+RSTRING_LEN(str), enc);
-		if (MBCLEN_NEEDMORE_P(r)) {
-		    goto getc_needmore;
-		}
-		else if (MBCLEN_CHARFOUND_P(r)) {
-		    cr = ENC_CODERANGE_VALID;
-		}
-	    }
-	}
-	else {
-	    str = rb_str_new(fptr->rbuf.ptr+fptr->rbuf.off, 1);
-	    fptr->rbuf.off++;
-	    fptr->rbuf.len--;
-	}
+        r = rb_enc_precise_mbclen(fptr->rbuf.ptr+fptr->rbuf.off, fptr->rbuf.ptr+fptr->rbuf.off+fptr->rbuf.len, enc);
+        if (MBCLEN_CHARFOUND_P(r) &&
+            (n = MBCLEN_CHARFOUND_LEN(r)) <= fptr->rbuf.len) {
+            str = rb_str_new(fptr->rbuf.ptr+fptr->rbuf.off, n);
+            fptr->rbuf.off += n;
+            fptr->rbuf.len -= n;
+            cr = ENC_CODERANGE_VALID;
+        }
+        else if (MBCLEN_NEEDMORE_P(r)) {
+            str = rb_str_new(fptr->rbuf.ptr+fptr->rbuf.off, fptr->rbuf.len);
+            fptr->rbuf.len = 0;
+          getc_needmore:
+            if (io_fillbuf(fptr) != -1) {
+                rb_str_cat(str, fptr->rbuf.ptr+fptr->rbuf.off, 1);
+                fptr->rbuf.off++;
+                fptr->rbuf.len--;
+                r = rb_enc_precise_mbclen(RSTRING_PTR(str), RSTRING_PTR(str)+RSTRING_LEN(str), enc);
+                if (MBCLEN_NEEDMORE_P(r)) {
+                    goto getc_needmore;
+                }
+                else if (MBCLEN_CHARFOUND_P(r)) {
+                    cr = ENC_CODERANGE_VALID;
+                }
+            }
+        }
+        else {
+            str = rb_str_new(fptr->rbuf.ptr+fptr->rbuf.off, 1);
+            fptr->rbuf.off++;
+            fptr->rbuf.len--;
+        }
     }
     if (!cr) cr = ENC_CODERANGE_BROKEN;
     str = io_enc_str(str, fptr);
@@ -4516,7 +4783,8 @@ io_getc(rb_io_t *fptr, rb_encoding *enc)
  *    each_char {|c| ... } -> self
  *    each_char            -> enumerator
  *
- *  Calls the given block with each character in the stream; returns +self+:
+ *  Calls the given block with each character in the stream; returns +self+.
+ *  See {Character IO}[rdoc-ref:IO@Character+IO].
  *
  *    f = File.new('t.rus')
  *    a = []
@@ -4582,87 +4850,87 @@ rb_io_each_codepoint(VALUE io)
 
     READ_CHECK(fptr);
     if (NEED_READCONV(fptr)) {
-	SET_BINARY_MODE(fptr);
-	r = 1;		/* no invalid char yet */
-	for (;;) {
-	    make_readconv(fptr, 0);
-	    for (;;) {
-		if (fptr->cbuf.len) {
-		    if (fptr->encs.enc)
-			r = rb_enc_precise_mbclen(fptr->cbuf.ptr+fptr->cbuf.off,
-						  fptr->cbuf.ptr+fptr->cbuf.off+fptr->cbuf.len,
-						  fptr->encs.enc);
-		    else
-			r = ONIGENC_CONSTRUCT_MBCLEN_CHARFOUND(1);
-		    if (!MBCLEN_NEEDMORE_P(r))
-			break;
-		    if (fptr->cbuf.len == fptr->cbuf.capa) {
-			rb_raise(rb_eIOError, "too long character");
-		    }
-		}
-		if (more_char(fptr) == MORE_CHAR_FINISHED) {
+        SET_BINARY_MODE(fptr);
+        r = 1;		/* no invalid char yet */
+        for (;;) {
+            make_readconv(fptr, 0);
+            for (;;) {
+                if (fptr->cbuf.len) {
+                    if (fptr->encs.enc)
+                        r = rb_enc_precise_mbclen(fptr->cbuf.ptr+fptr->cbuf.off,
+                                                  fptr->cbuf.ptr+fptr->cbuf.off+fptr->cbuf.len,
+                                                  fptr->encs.enc);
+                    else
+                        r = ONIGENC_CONSTRUCT_MBCLEN_CHARFOUND(1);
+                    if (!MBCLEN_NEEDMORE_P(r))
+                        break;
+                    if (fptr->cbuf.len == fptr->cbuf.capa) {
+                        rb_raise(rb_eIOError, "too long character");
+                    }
+                }
+                if (more_char(fptr) == MORE_CHAR_FINISHED) {
                     clear_readconv(fptr);
-		    if (!MBCLEN_CHARFOUND_P(r)) {
-			enc = fptr->encs.enc;
-			goto invalid;
-		    }
-		    return io;
-		}
-	    }
-	    if (MBCLEN_INVALID_P(r)) {
-		enc = fptr->encs.enc;
-		goto invalid;
-	    }
-	    n = MBCLEN_CHARFOUND_LEN(r);
-	    if (fptr->encs.enc) {
-		c = rb_enc_codepoint(fptr->cbuf.ptr+fptr->cbuf.off,
-				     fptr->cbuf.ptr+fptr->cbuf.off+fptr->cbuf.len,
-				     fptr->encs.enc);
-	    }
-	    else {
-		c = (unsigned char)fptr->cbuf.ptr[fptr->cbuf.off];
-	    }
-	    fptr->cbuf.off += n;
-	    fptr->cbuf.len -= n;
-	    rb_yield(UINT2NUM(c));
+                    if (!MBCLEN_CHARFOUND_P(r)) {
+                        enc = fptr->encs.enc;
+                        goto invalid;
+                    }
+                    return io;
+                }
+            }
+            if (MBCLEN_INVALID_P(r)) {
+                enc = fptr->encs.enc;
+                goto invalid;
+            }
+            n = MBCLEN_CHARFOUND_LEN(r);
+            if (fptr->encs.enc) {
+                c = rb_enc_codepoint(fptr->cbuf.ptr+fptr->cbuf.off,
+                                     fptr->cbuf.ptr+fptr->cbuf.off+fptr->cbuf.len,
+                                     fptr->encs.enc);
+            }
+            else {
+                c = (unsigned char)fptr->cbuf.ptr[fptr->cbuf.off];
+            }
+            fptr->cbuf.off += n;
+            fptr->cbuf.len -= n;
+            rb_yield(UINT2NUM(c));
             rb_io_check_byte_readable(fptr);
-	}
+        }
     }
     NEED_NEWLINE_DECORATOR_ON_READ_CHECK(fptr);
     enc = io_input_encoding(fptr);
     while (io_fillbuf(fptr) >= 0) {
-	r = rb_enc_precise_mbclen(fptr->rbuf.ptr+fptr->rbuf.off,
-				  fptr->rbuf.ptr+fptr->rbuf.off+fptr->rbuf.len, enc);
-	if (MBCLEN_CHARFOUND_P(r) &&
-	    (n = MBCLEN_CHARFOUND_LEN(r)) <= fptr->rbuf.len) {
-	    c = rb_enc_codepoint(fptr->rbuf.ptr+fptr->rbuf.off,
-				 fptr->rbuf.ptr+fptr->rbuf.off+fptr->rbuf.len, enc);
-	    fptr->rbuf.off += n;
-	    fptr->rbuf.len -= n;
-	    rb_yield(UINT2NUM(c));
-	}
-	else if (MBCLEN_INVALID_P(r)) {
+        r = rb_enc_precise_mbclen(fptr->rbuf.ptr+fptr->rbuf.off,
+                                  fptr->rbuf.ptr+fptr->rbuf.off+fptr->rbuf.len, enc);
+        if (MBCLEN_CHARFOUND_P(r) &&
+            (n = MBCLEN_CHARFOUND_LEN(r)) <= fptr->rbuf.len) {
+            c = rb_enc_codepoint(fptr->rbuf.ptr+fptr->rbuf.off,
+                                 fptr->rbuf.ptr+fptr->rbuf.off+fptr->rbuf.len, enc);
+            fptr->rbuf.off += n;
+            fptr->rbuf.len -= n;
+            rb_yield(UINT2NUM(c));
+        }
+        else if (MBCLEN_INVALID_P(r)) {
             goto invalid;
-	}
-	else if (MBCLEN_NEEDMORE_P(r)) {
-	    char cbuf[8], *p = cbuf;
-	    int more = MBCLEN_NEEDMORE_LEN(r);
-	    if (more > numberof(cbuf)) goto invalid;
-	    more += n = fptr->rbuf.len;
-	    if (more > numberof(cbuf)) goto invalid;
-	    while ((n = (int)read_buffered_data(p, more, fptr)) > 0 &&
-		   (p += n, (more -= n) > 0)) {
-		if (io_fillbuf(fptr) < 0) goto invalid;
-		if ((n = fptr->rbuf.len) > more) n = more;
-	    }
-	    r = rb_enc_precise_mbclen(cbuf, p, enc);
-	    if (!MBCLEN_CHARFOUND_P(r)) goto invalid;
-	    c = rb_enc_codepoint(cbuf, p, enc);
-	    rb_yield(UINT2NUM(c));
-	}
-	else {
-	    continue;
-	}
+        }
+        else if (MBCLEN_NEEDMORE_P(r)) {
+            char cbuf[8], *p = cbuf;
+            int more = MBCLEN_NEEDMORE_LEN(r);
+            if (more > numberof(cbuf)) goto invalid;
+            more += n = fptr->rbuf.len;
+            if (more > numberof(cbuf)) goto invalid;
+            while ((n = (int)read_buffered_data(p, more, fptr)) > 0 &&
+                   (p += n, (more -= n) > 0)) {
+                if (io_fillbuf(fptr) < 0) goto invalid;
+                if ((n = fptr->rbuf.len) > more) n = more;
+            }
+            r = rb_enc_precise_mbclen(cbuf, p, enc);
+            if (!MBCLEN_CHARFOUND_P(r)) goto invalid;
+            c = rb_enc_codepoint(cbuf, p, enc);
+            rb_yield(UINT2NUM(c));
+        }
+        else {
+            continue;
+        }
         rb_io_check_byte_readable(fptr);
     }
     return io;
@@ -4677,7 +4945,8 @@ rb_io_each_codepoint(VALUE io)
  *    getc -> character or nil
  *
  *  Reads and returns the next 1-character string from the stream;
- *  returns +nil+ if already at end-of-file:
+ *  returns +nil+ if already at end-of-stream.
+ *  See {Character IO}[rdoc-ref:IO@Character+IO].
  *
  *    f = File.open('t.txt')
  *    f.getc     # => "F"
@@ -4709,7 +4978,8 @@ rb_io_getc(VALUE io)
  *    readchar -> string
  *
  *  Reads and returns the next 1-character string from the stream;
- *  raises EOFError if already at end-of-file:
+ *  raises EOFError if already at end-of-stream.
+ *  See {Character IO}[rdoc-ref:IO@Character+IO].
  *
  *    f = File.open('t.txt')
  *    f.readchar     # => "F"
@@ -4728,7 +4998,7 @@ rb_io_readchar(VALUE io)
     VALUE c = rb_io_getc(io);
 
     if (NIL_P(c)) {
-	rb_eof_error();
+        rb_eof_error();
     }
     return c;
 }
@@ -4738,7 +5008,8 @@ rb_io_readchar(VALUE io)
  *    getbyte -> integer or nil
  *
  *  Reads and returns the next byte (in range 0..255) from the stream;
- *  returns +nil+ if already at end-of-file:
+ *  returns +nil+ if already at end-of-stream.
+ *  See {Byte IO}[rdoc-ref:IO@Byte+IO].
  *
  *    f = File.open('t.txt')
  *    f.getbyte # => 70
@@ -4748,7 +5019,6 @@ rb_io_readchar(VALUE io)
  *    f.close
  *
  *  Related: IO#readbyte (may raise EOFError).
- *
  */
 
 VALUE
@@ -4769,7 +5039,7 @@ rb_io_getbyte(VALUE io)
         }
     }
     if (io_fillbuf(fptr) < 0) {
-	return Qnil;
+        return Qnil;
     }
     fptr->rbuf.off++;
     fptr->rbuf.len--;
@@ -4782,7 +5052,8 @@ rb_io_getbyte(VALUE io)
  *    readbyte -> integer
  *
  *  Reads and returns the next byte (in range 0..255) from the stream;
- *  raises EOFError if already at end-of-file:
+ *  raises EOFError if already at end-of-stream.
+ *  See {Byte IO}[rdoc-ref:IO@Byte+IO].
  *
  *    f = File.open('t.txt')
  *    f.readbyte # => 70
@@ -4801,7 +5072,7 @@ rb_io_readbyte(VALUE io)
     VALUE c = rb_io_getbyte(io);
 
     if (NIL_P(c)) {
-	rb_eof_error();
+        rb_eof_error();
     }
     return c;
 }
@@ -4813,10 +5084,11 @@ rb_io_readbyte(VALUE io)
  *
  *  Pushes back ("unshifts") the given data onto the stream's buffer,
  *  placing the data so that it is next to be read; returns +nil+.
+ *  See {Byte IO}[rdoc-ref:IO@Byte+IO].
  *
  *  Note that:
  *
- *  - Calling the method hs no effect with unbuffered reads (such as IO#sysread).
+ *  - Calling the method has no effect with unbuffered reads (such as IO#sysread).
  *  - Calling #rewind on the stream discards the pushed-back data.
  *
  *  When argument +integer+ is given, uses only its low-order byte:
@@ -4873,10 +5145,11 @@ rb_io_ungetbyte(VALUE io, VALUE b)
  *
  *  Pushes back ("unshifts") the given data onto the stream's buffer,
  *  placing the data so that it is next to be read; returns +nil+.
+ *  See {Character IO}[rdoc-ref:IO@Character+IO].
  *
  *  Note that:
  *
- *  - Calling the method hs no effect with unbuffered reads (such as IO#sysread).
+ *  - Calling the method has no effect with unbuffered reads (such as IO#sysread).
  *  - Calling #rewind on the stream discards the pushed-back data.
  *
  *  When argument +integer+ is given, interprets the integer as a character:
@@ -4915,20 +5188,20 @@ rb_io_ungetc(VALUE io, VALUE c)
     GetOpenFile(io, fptr);
     rb_io_check_char_readable(fptr);
     if (FIXNUM_P(c)) {
-	c = rb_enc_uint_chr(FIX2UINT(c), io_read_encoding(fptr));
+        c = rb_enc_uint_chr(FIX2UINT(c), io_read_encoding(fptr));
     }
     else if (RB_BIGNUM_TYPE_P(c)) {
-	c = rb_enc_uint_chr(NUM2UINT(c), io_read_encoding(fptr));
+        c = rb_enc_uint_chr(NUM2UINT(c), io_read_encoding(fptr));
     }
     else {
-	SafeStringValue(c);
+        SafeStringValue(c);
     }
     if (NEED_READCONV(fptr)) {
-	SET_BINARY_MODE(fptr);
+        SET_BINARY_MODE(fptr);
         len = RSTRING_LEN(c);
 #if SIZEOF_LONG > SIZEOF_INT
-	if (len > INT_MAX)
-	    rb_raise(rb_eIOError, "ungetc failed");
+        if (len > INT_MAX)
+            rb_raise(rb_eIOError, "ungetc failed");
 #endif
         make_readconv(fptr, (int)len);
         if (fptr->cbuf.capa - fptr->cbuf.len < len)
@@ -4944,7 +5217,7 @@ rb_io_ungetc(VALUE io, VALUE c)
         MEMMOVE(fptr->cbuf.ptr+fptr->cbuf.off, RSTRING_PTR(c), char, len);
     }
     else {
-	NEED_NEWLINE_DECORATOR_ON_READ_CHECK(fptr);
+        NEED_NEWLINE_DECORATOR_ON_READ_CHECK(fptr);
         io_ungetbyte(c, fptr);
     }
     return Qnil;
@@ -4957,8 +5230,10 @@ rb_io_ungetc(VALUE io, VALUE c)
  *  Returns +true+ if the stream is associated with a terminal device (tty),
  *  +false+ otherwise:
  *
- *     File.new('t.txt').isatty    #=> false
- *     File.new('/dev/tty').isatty #=> true
+ *    f = File.new('t.txt').isatty    #=> false
+ *    f.close
+ *    f = File.new('/dev/tty').isatty #=> true
+ *    f.close
  *
  *  IO#tty? is an alias for IO#isatty.
  *
@@ -5084,7 +5359,6 @@ finish_writeconv(rb_io_t *fptr, int noalloc)
 
     if (!fptr->wbuf.ptr) {
         unsigned char buf[1024];
-        long r;
 
         res = econv_destination_buffer_full;
         while (res == econv_destination_buffer_full) {
@@ -5092,19 +5366,20 @@ finish_writeconv(rb_io_t *fptr, int noalloc)
             de = buf + sizeof(buf);
             res = rb_econv_convert(fptr->writeconv, NULL, NULL, &dp, de, 0);
             while (dp-ds) {
-              retry:
-                r = rb_write_internal(fptr, ds, dp-ds);
-                if (r == dp-ds)
-                    break;
-                if (0 <= r) {
-                    ds += r;
+                size_t remaining = dp-ds;
+                long result = rb_io_write_memory(fptr, ds, remaining);
+
+                if (result > 0) {
+                    ds += result;
+                    if ((size_t)result == remaining) break;
                 }
-                if (rb_io_maybe_wait_writable(errno, fptr->self, Qnil)) {
+                else if (rb_io_maybe_wait_writable(errno, fptr->self, RUBY_IO_TIMEOUT_DEFAULT)) {
                     if (fptr->fd < 0)
                         return noalloc ? Qtrue : rb_exc_new3(rb_eIOError, rb_str_new_cstr(closed_stream));
-                    goto retry;
                 }
-                return noalloc ? Qtrue : INT2NUM(errno);
+                else {
+                    return noalloc ? Qtrue : INT2NUM(errno);
+                }
             }
             if (res == econv_invalid_byte_sequence ||
                 res == econv_incomplete_input ||
@@ -5119,8 +5394,9 @@ finish_writeconv(rb_io_t *fptr, int noalloc)
     res = econv_destination_buffer_full;
     while (res == econv_destination_buffer_full) {
         if (fptr->wbuf.len == fptr->wbuf.capa) {
-            if (io_fflush(fptr) < 0)
+            if (io_fflush(fptr) < 0) {
                 return noalloc ? Qtrue : INT2NUM(errno);
+            }
         }
 
         ds = dp = (unsigned char *)fptr->wbuf.ptr + fptr->wbuf.off + fptr->wbuf.len;
@@ -5193,20 +5469,20 @@ static void
 fptr_finalize_flush(rb_io_t *fptr, int noraise, int keepgvl,
                     struct ccan_list_head *busy)
 {
-    VALUE err = Qnil;
+    VALUE error = Qnil;
     int fd = fptr->fd;
     FILE *stdio_file = fptr->stdio_file;
     int mode = fptr->mode;
 
     if (fptr->writeconv) {
-        if (fptr->write_lock && !noraise) {
+        if (!NIL_P(fptr->write_lock) && !noraise) {
             struct finish_writeconv_arg arg;
             arg.fptr = fptr;
             arg.noalloc = noraise;
-            err = rb_mutex_synchronize(fptr->write_lock, finish_writeconv_sync, (VALUE)&arg);
+            error = rb_mutex_synchronize(fptr->write_lock, finish_writeconv_sync, (VALUE)&arg);
         }
         else {
-            err = finish_writeconv(fptr, noraise);
+            error = finish_writeconv(fptr, noraise);
         }
     }
     if (fptr->wbuf.len) {
@@ -5214,8 +5490,9 @@ fptr_finalize_flush(rb_io_t *fptr, int noraise, int keepgvl,
             io_flush_buffer_sync(fptr);
         }
         else {
-            if (io_fflush(fptr) < 0 && NIL_P(err))
-        	err = INT2NUM(errno);
+            if (io_fflush(fptr) < 0 && NIL_P(error)) {
+                error = INT2NUM(errno);
+            }
         }
     }
 
@@ -5241,14 +5518,17 @@ fptr_finalize_flush(rb_io_t *fptr, int noraise, int keepgvl,
     //     VALUE scheduler = rb_fiber_scheduler_current();
     //     if (scheduler != Qnil) {
     //         VALUE result = rb_fiber_scheduler_io_close(scheduler, fptr->self);
-    //         if (result != Qundef) done = 1;
+    //         if (!UNDEF_P(result)) done = 1;
     //     }
     // }
 
     if (!done && stdio_file) {
         // stdio_file is deallocated anyway even if fclose failed.
-        if ((maygvl_fclose(stdio_file, noraise) < 0) && NIL_P(err))
-            if (!noraise) err = INT2NUM(errno);
+        if ((maygvl_fclose(stdio_file, noraise) < 0) && NIL_P(error)) {
+            if (!noraise) {
+                error = INT2NUM(errno);
+            }
+        }
 
         done = 1;
     }
@@ -5259,17 +5539,20 @@ fptr_finalize_flush(rb_io_t *fptr, int noraise, int keepgvl,
 
         keepgvl |= !(mode & FMODE_WRITABLE);
         keepgvl |= noraise;
-        if ((maygvl_close(fd, keepgvl) < 0) && NIL_P(err))
-            if (!noraise) err = INT2NUM(errno);
+        if ((maygvl_close(fd, keepgvl) < 0) && NIL_P(error)) {
+            if (!noraise) {
+                error = INT2NUM(errno);
+            }
+        }
 
         done = 1;
     }
 
-    if (!NIL_P(err) && !noraise) {
-        if (RB_INTEGER_TYPE_P(err))
-            rb_syserr_fail_path(NUM2INT(err), fptr->pathv);
+    if (!NIL_P(error) && !noraise) {
+        if (RB_INTEGER_TYPE_P(error))
+            rb_syserr_fail_path(NUM2INT(error), fptr->pathv);
         else
-            rb_exc_raise(err);
+            rb_exc_raise(error);
     }
 }
 
@@ -5286,10 +5569,10 @@ static void
 rb_io_fptr_cleanup(rb_io_t *fptr, int noraise)
 {
     if (fptr->finalize) {
-	(*fptr->finalize)(fptr, noraise);
+        (*fptr->finalize)(fptr, noraise);
     }
     else {
-	fptr_finalize(fptr, noraise);
+        fptr_finalize(fptr, noraise);
     }
 }
 
@@ -5338,7 +5621,7 @@ rb_io_fptr_finalize_internal(void *ptr)
     fptr->pathv = Qnil;
     if (0 <= fptr->fd)
         rb_io_fptr_cleanup(fptr, TRUE);
-    fptr->write_lock = 0;
+    fptr->write_lock = Qnil;
     free_io_buffer(&fptr->rbuf);
     free_io_buffer(&fptr->wbuf);
     clear_codeconv(fptr);
@@ -5431,12 +5714,32 @@ rb_io_close(VALUE io)
  *  call-seq:
  *    close -> nil
  *
- *  Closes the stream, if it is open, after flushing any buffered writes
- *  to the operating system; does nothing if the stream is already closed.
- *  A stream is automatically closed when claimed by the garbage collector.
+ *  Closes the stream for both reading and writing
+ *  if open for either or both; returns +nil+.
+ *  See {Open and Closed Streams}[rdoc-ref:IO@Open+and+Closed+Streams].
+ *
+ *  If the stream is open for writing, flushes any buffered writes
+ *  to the operating system before closing.
  *
- *  If the stream was opened by IO.popen, #close sets global variable <tt>$?</tt>.
+ *  If the stream was opened by IO.popen, sets global variable <tt>$?</tt>
+ *  (child exit status).
+ *
+ *  Example:
  *
+ *    IO.popen('ruby', 'r+') do |pipe|
+ *      puts pipe.closed?
+ *      pipe.close
+ *      puts $?
+ *      puts pipe.closed?
+ *    end
+ *
+ *  Output:
+ *
+ *    false
+ *    pid 13760 exit 0
+ *    true
+ *
+ *  Related: IO#close_read, IO#close_write, IO#closed?.
  */
 
 static VALUE
@@ -5463,9 +5766,9 @@ ignore_closed_stream(VALUE io, VALUE exc)
     enum {mesg_len = sizeof(closed_stream)-1};
     VALUE mesg = rb_attr_get(exc, idMesg);
     if (!RB_TYPE_P(mesg, T_STRING) ||
-	RSTRING_LEN(mesg) != mesg_len ||
-	memcmp(RSTRING_PTR(mesg), closed_stream, mesg_len)) {
-	rb_exc_raise(exc);
+        RSTRING_LEN(mesg) != mesg_len ||
+        memcmp(RSTRING_PTR(mesg), closed_stream, mesg_len)) {
+        rb_exc_raise(exc);
     }
     return io;
 }
@@ -5474,9 +5777,9 @@ static VALUE
 io_close(VALUE io)
 {
     VALUE closed = rb_check_funcall(io, rb_intern("closed?"), 0, 0);
-    if (closed != Qundef && RTEST(closed)) return io;
+    if (!UNDEF_P(closed) && RTEST(closed)) return io;
     rb_rescue2(io_call_close, io, ignore_closed_stream, io,
-	       rb_eIOError, (VALUE)0);
+               rb_eIOError, (VALUE)0);
     return io;
 }
 
@@ -5485,17 +5788,24 @@ io_close(VALUE io)
  *    closed? -> true or false
  *
  *  Returns +true+ if the stream is closed for both reading and writing,
- *  +false+ otherwise:
+ *  +false+ otherwise.
+ *  See {Open and Closed Streams}[rdoc-ref:IO@Open+and+Closed+Streams].
  *
- *    f = File.new('t.txt')
- *    f.close        # => nil
- *    f.closed?      # => true
- *    f = IO.popen('/bin/sh','r+')
- *    f.close_write  # => nil
- *    f.closed?      # => false
- *    f.close_read   # => nil
- *    f.closed?      # => true
+ *    IO.popen('ruby', 'r+') do |pipe|
+ *      puts pipe.closed?
+ *      pipe.close_read
+ *      puts pipe.closed?
+ *      pipe.close_write
+ *      puts pipe.closed?
+ *    end
+ *
+ *  Output:
  *
+ *    false
+ *    false
+ *    true
+ *
+ *  Related: IO#close_read, IO#close_write, IO#close.
  */
 
 
@@ -5522,15 +5832,32 @@ rb_io_closed(VALUE io)
  *  call-seq:
  *    close_read -> nil
  *
- *  Closes the read end of a duplexed stream (i.e., one that is both readable
- *  and writable, such as a pipe); does nothing if already closed:
+ *  Closes the stream for reading if open for reading;
+ *  returns +nil+.
+ *  See {Open and Closed Streams}[rdoc-ref:IO@Open+and+Closed+Streams].
+ *
+ *  If the stream was opened by IO.popen and is also closed for writing,
+ *  sets global variable <tt>$?</tt> (child exit status).
+ *
+ *  Example:
+ *
+ *    IO.popen('ruby', 'r+') do |pipe|
+ *      puts pipe.closed?
+ *      pipe.close_write
+ *      puts pipe.closed?
+ *      pipe.close_read
+ *      puts $?
+ *      puts pipe.closed?
+ *    end
  *
- *    f = IO.popen('/bin/sh','r+')
- *    f.close_read
- *    f.readlines # Raises IOError
+ *  Output:
  *
- *  Raises an exception if the stream is not duplexed.
+ *    false
+ *    false
+ *    pid 14748 exit 0
+ *    true
  *
+ *  Related: IO#close, IO#close_write, IO#closed?.
  */
 
 static VALUE
@@ -5555,21 +5882,21 @@ rb_io_close_read(VALUE io)
 
     write_io = GetWriteIO(io);
     if (io != write_io) {
-	rb_io_t *wfptr;
-	wfptr = rb_io_get_fptr(rb_io_taint_check(write_io));
-	wfptr->pid = fptr->pid;
-	fptr->pid = 0;
+        rb_io_t *wfptr;
+        wfptr = rb_io_get_fptr(rb_io_taint_check(write_io));
+        wfptr->pid = fptr->pid;
+        fptr->pid = 0;
         RFILE(io)->fptr = wfptr;
-	/* bind to write_io temporarily to get rid of memory/fd leak */
-	fptr->tied_io_for_writing = 0;
-	RFILE(write_io)->fptr = fptr;
-	rb_io_fptr_cleanup(fptr, FALSE);
-	/* should not finalize fptr because another thread may be reading it */
+        /* bind to write_io temporarily to get rid of memory/fd leak */
+        fptr->tied_io_for_writing = 0;
+        RFILE(write_io)->fptr = fptr;
+        rb_io_fptr_cleanup(fptr, FALSE);
+        /* should not finalize fptr because another thread may be reading it */
         return Qnil;
     }
 
     if ((fptr->mode & (FMODE_DUPLEX|FMODE_WRITABLE)) == FMODE_WRITABLE) {
-	rb_raise(rb_eIOError, "closing non-duplex IO for reading");
+        rb_raise(rb_eIOError, "closing non-duplex IO for reading");
     }
     return rb_io_close(io);
 }
@@ -5578,13 +5905,32 @@ rb_io_close_read(VALUE io)
  *  call-seq:
  *    close_write -> nil
  *
- *  Closes the write end of a duplexed stream (i.e., one that is both readable
- *  and writable, such as a pipe); does nothing if already closed:
+ *  Closes the stream for writing if open for writing;
+ *  returns +nil+.
+ *  See {Open and Closed Streams}[rdoc-ref:IO@Open+and+Closed+Streams].
+ *
+ *  Flushes any buffered writes to the operating system before closing.
+ *
+ *  If the stream was opened by IO.popen and is also closed for reading,
+ *  sets global variable <tt>$?</tt> (child exit status).
  *
- *    f = IO.popen('/bin/sh', 'r+')
- *    f.close_write
- *    f.print 'nowhere' # Raises IOError.
+ *    IO.popen('ruby', 'r+') do |pipe|
+ *      puts pipe.closed?
+ *      pipe.close_read
+ *      puts pipe.closed?
+ *      pipe.close_write
+ *      puts $?
+ *      puts pipe.closed?
+ *    end
+ *
+ *  Output:
  *
+ *    false
+ *    false
+ *    pid 15044 exit 0
+ *    true
+ *
+ *  Related: IO#close, IO#close_read, IO#closed?.
  */
 
 static VALUE
@@ -5604,17 +5950,17 @@ rb_io_close_write(VALUE io)
             rb_sys_fail_path(fptr->pathv);
         fptr->mode &= ~FMODE_WRITABLE;
         if (!(fptr->mode & FMODE_READABLE))
-	    return rb_io_close(write_io);
+            return rb_io_close(write_io);
         return Qnil;
     }
 
     if ((fptr->mode & (FMODE_DUPLEX|FMODE_READABLE)) == FMODE_READABLE) {
-	rb_raise(rb_eIOError, "closing non-duplex IO for writing");
+        rb_raise(rb_eIOError, "closing non-duplex IO for writing");
     }
 
     if (io != write_io) {
-	fptr = rb_io_get_fptr(rb_io_taint_check(io));
-	fptr->tied_io_for_writing = 0;
+        fptr = rb_io_get_fptr(rb_io_taint_check(io));
+        fptr->tied_io_for_writing = 0;
     }
     rb_io_close(write_io);
     return Qnil;
@@ -5637,19 +5983,19 @@ rb_io_sysseek(int argc, VALUE *argv, VALUE io)
     VALUE offset, ptrname;
     int whence = SEEK_SET;
     rb_io_t *fptr;
-    off_t pos;
+    rb_off_t pos;
 
     if (rb_scan_args(argc, argv, "11", &offset, &ptrname) == 2) {
-	whence = interpret_seek_whence(ptrname);
+        whence = interpret_seek_whence(ptrname);
     }
     pos = NUM2OFFT(offset);
     GetOpenFile(io, fptr);
     if ((fptr->mode & FMODE_READABLE) &&
         (READ_DATA_BUFFERED(fptr) || READ_CHAR_PENDING(fptr))) {
-	rb_raise(rb_eIOError, "sysseek for buffered IO");
+        rb_raise(rb_eIOError, "sysseek for buffered IO");
     }
     if ((fptr->mode & FMODE_WRITABLE) && fptr->wbuf.len) {
-	rb_warn("sysseek for buffered IO");
+        rb_warn("sysseek for buffered IO");
     }
     errno = 0;
     pos = lseek(fptr->fd, pos, whence);
@@ -5685,19 +6031,19 @@ rb_io_syswrite(VALUE io, VALUE str)
     const char *ptr;
 
     if (!RB_TYPE_P(str, T_STRING))
-	str = rb_obj_as_string(str);
+        str = rb_obj_as_string(str);
 
     io = GetWriteIO(io);
     GetOpenFile(io, fptr);
     rb_io_check_writable(fptr);
 
     if (fptr->wbuf.len) {
-	rb_warn("syswrite for buffered IO");
+        rb_warn("syswrite for buffered IO");
     }
 
     tmp = rb_str_tmp_frozen_acquire(str);
     RSTRING_GETMEM(tmp, ptr, len);
-    n = rb_write_internal(fptr, ptr, len);
+    n = rb_io_write_memory(fptr, ptr, len);
     if (n < 0) rb_sys_fail_path(fptr->pathv);
     rb_str_tmp_frozen_release(str, tmp);
 
@@ -5743,9 +6089,11 @@ rb_io_sysread(int argc, VALUE *argv, VALUE io)
     iis.th = rb_thread_current();
     iis.fptr = fptr;
     iis.nonblock = 0;
+    iis.fd = fptr->fd;
     iis.buf = RSTRING_PTR(str);
     iis.capa = ilen;
-    n = read_internal_locktmp(str, &iis);
+    iis.timeout = NULL;
+    n = io_read_memory_locktmp(str, &iis);
 
     if (n < 0) {
         rb_sys_fail_path(fptr->pathv);
@@ -5765,7 +6113,7 @@ struct prdwr_internal_arg {
     int fd;
     void *buf;
     size_t count;
-    off_t offset;
+    rb_off_t offset;
 };
 #endif /* HAVE_PREAD || HAVE_PWRITE */
 
@@ -5839,11 +6187,11 @@ rb_io_pread(int argc, VALUE *argv, VALUE io)
     n = (ssize_t)rb_ensure(pread_internal_call, (VALUE)&arg, rb_str_unlocktmp, str);
 
     if (n < 0) {
-	rb_sys_fail_path(fptr->pathv);
+        rb_sys_fail_path(fptr->pathv);
     }
     io_set_read_length(str, n, shrinkable);
     if (n == 0 && arg.count > 0) {
-	rb_eof_error();
+        rb_eof_error();
     }
 
     return str;
@@ -5895,7 +6243,7 @@ rb_io_pwrite(VALUE io, VALUE str, VALUE offset)
     VALUE tmp;
 
     if (!RB_TYPE_P(str, T_STRING))
-	str = rb_obj_as_string(str);
+        str = rb_obj_as_string(str);
 
     arg.offset = NUM2OFFT(offset);
 
@@ -5933,10 +6281,10 @@ rb_io_binmode(VALUE io)
     fptr->writeconv_pre_ecflags &= ~ECONV_NEWLINE_DECORATOR_MASK;
 #ifdef O_BINARY
     if (!fptr->readconv) {
-	SET_BINARY_MODE_WITH_SEEK_CUR(fptr);
+        SET_BINARY_MODE_WITH_SEEK_CUR(fptr);
     }
     else {
-	setmode(fptr->fd, O_BINARY);
+        setmode(fptr->fd, O_BINARY);
     }
 #endif
     return io;
@@ -5980,7 +6328,7 @@ rb_io_ascii8bit_binmode(VALUE io)
  *    binmode -> self
  *
  *  Sets the stream's data mode as binary
- *  (see {Data Mode}[rdoc-ref:IO@Data+Mode]).
+ *  (see {Data Mode}[rdoc-ref:File@Data+Mode]).
  *
  *  A stream's data mode may not be changed from binary to text.
  *
@@ -6004,7 +6352,7 @@ rb_io_binmode_m(VALUE io)
  *    binmode? -> true or false
  *
  *  Returns +true+ if the stream is on binary mode, +false+ otherwise.
- *  See {Data Mode}[rdoc-ref:IO@Data+Mode].
+ *  See {Data Mode}[rdoc-ref:File@Data+Mode].
  *
  */
 static VALUE
@@ -6019,23 +6367,23 @@ static const char*
 rb_io_fmode_modestr(int fmode)
 {
     if (fmode & FMODE_APPEND) {
-	if ((fmode & FMODE_READWRITE) == FMODE_READWRITE) {
-	    return MODE_BTMODE("a+", "ab+", "at+");
-	}
-	return MODE_BTMODE("a", "ab", "at");
+        if ((fmode & FMODE_READWRITE) == FMODE_READWRITE) {
+            return MODE_BTMODE("a+", "ab+", "at+");
+        }
+        return MODE_BTMODE("a", "ab", "at");
     }
     switch (fmode & FMODE_READWRITE) {
       default:
-	rb_raise(rb_eArgError, "invalid access fmode 0x%x", fmode);
+        rb_raise(rb_eArgError, "invalid access fmode 0x%x", fmode);
       case FMODE_READABLE:
-	return MODE_BTMODE("r", "rb", "rt");
+        return MODE_BTMODE("r", "rb", "rt");
       case FMODE_WRITABLE:
-	return MODE_BTXMODE("w", "wb", "wt", "wx", "wbx", "wtx");
+        return MODE_BTXMODE("w", "wb", "wt", "wx", "wbx", "wtx");
       case FMODE_READWRITE:
-	if (fmode & FMODE_CREATE) {
+        if (fmode & FMODE_CREATE) {
             return MODE_BTXMODE("w+", "wb+", "wt+", "w+x", "wb+x", "wt+x");
-	}
-	return MODE_BTMODE("r+", "rb+", "rt+");
+        }
+        return MODE_BTMODE("r+", "rb+", "rt+");
     }
 }
 
@@ -6058,27 +6406,27 @@ rb_io_modestr_fmode(const char *modestr)
 
     switch (*m++) {
       case 'r':
-	fmode |= FMODE_READABLE;
-	break;
+        fmode |= FMODE_READABLE;
+        break;
       case 'w':
-	fmode |= FMODE_WRITABLE | FMODE_TRUNC | FMODE_CREATE;
-	break;
+        fmode |= FMODE_WRITABLE | FMODE_TRUNC | FMODE_CREATE;
+        break;
       case 'a':
-	fmode |= FMODE_WRITABLE | FMODE_APPEND | FMODE_CREATE;
-	break;
+        fmode |= FMODE_WRITABLE | FMODE_APPEND | FMODE_CREATE;
+        break;
       default:
         goto error;
     }
 
     while (*m) {
         switch (*m++) {
-	  case 'b':
+          case 'b':
             fmode |= FMODE_BINMODE;
             break;
-	  case 't':
+          case 't':
             fmode |= FMODE_TEXTMODE;
             break;
-	  case '+':
+          case '+':
             fmode |= FMODE_READWRITE;
             break;
           case 'x':
@@ -6086,12 +6434,12 @@ rb_io_modestr_fmode(const char *modestr)
                 goto error;
             fmode |= FMODE_EXCL;
             break;
-	  default:
+          default:
             goto error;
-	  case ':':
-	    p = strchr(m, ':');
-	    if (io_encname_bom_p(m, p ? (long)(p - m) : (long)strlen(m)))
-		fmode |= FMODE_SETENC_BY_BOM;
+          case ':':
+            p = strchr(m, ':');
+            if (io_encname_bom_p(m, p ? (long)(p - m) : (long)strlen(m)))
+                fmode |= FMODE_SETENC_BY_BOM;
             goto finished;
         }
     }
@@ -6114,31 +6462,31 @@ rb_io_oflags_fmode(int oflags)
 
     switch (oflags & O_ACCMODE) {
       case O_RDONLY:
-	fmode = FMODE_READABLE;
-	break;
+        fmode = FMODE_READABLE;
+        break;
       case O_WRONLY:
-	fmode = FMODE_WRITABLE;
-	break;
+        fmode = FMODE_WRITABLE;
+        break;
       case O_RDWR:
-	fmode = FMODE_READWRITE;
-	break;
+        fmode = FMODE_READWRITE;
+        break;
     }
 
     if (oflags & O_APPEND) {
-	fmode |= FMODE_APPEND;
+        fmode |= FMODE_APPEND;
     }
     if (oflags & O_TRUNC) {
-	fmode |= FMODE_TRUNC;
+        fmode |= FMODE_TRUNC;
     }
     if (oflags & O_CREAT) {
-	fmode |= FMODE_CREATE;
+        fmode |= FMODE_CREATE;
     }
     if (oflags & O_EXCL) {
         fmode |= FMODE_EXCL;
     }
 #ifdef O_BINARY
     if (oflags & O_BINARY) {
-	fmode |= FMODE_BINMODE;
+        fmode |= FMODE_BINMODE;
     }
 #endif
 
@@ -6203,25 +6551,25 @@ rb_io_oflags_modestr(int oflags)
     }
     accmode = oflags & (O_RDONLY|O_WRONLY|O_RDWR);
     if (oflags & O_APPEND) {
-	if (accmode == O_WRONLY) {
-	    return MODE_BINARY("a", "ab");
-	}
-	if (accmode == O_RDWR) {
-	    return MODE_BINARY("a+", "ab+");
-	}
+        if (accmode == O_WRONLY) {
+            return MODE_BINARY("a", "ab");
+        }
+        if (accmode == O_RDWR) {
+            return MODE_BINARY("a+", "ab+");
+        }
     }
     switch (accmode) {
       default:
-	rb_raise(rb_eArgError, "invalid access oflags 0x%x", oflags);
+        rb_raise(rb_eArgError, "invalid access oflags 0x%x", oflags);
       case O_RDONLY:
-	return MODE_BINARY("r", "rb");
+        return MODE_BINARY("r", "rb");
       case O_WRONLY:
-	return MODE_BINARY("w", "wb");
+        return MODE_BINARY("w", "wb");
       case O_RDWR:
-	if (oflags & O_TRUNC) {
-	    return MODE_BINARY("w+", "wb+");
-	}
-	return MODE_BINARY("r+", "rb+");
+        if (oflags & O_TRUNC) {
+            return MODE_BINARY("w+", "wb+");
+        }
+        return MODE_BINARY("r+", "rb+");
     }
 }
 
@@ -6236,25 +6584,25 @@ rb_io_ext_int_to_encs(rb_encoding *ext, rb_encoding *intern, rb_encoding **enc,
     int default_ext = 0;
 
     if (ext == NULL) {
-	ext = rb_default_external_encoding();
-	default_ext = 1;
+        ext = rb_default_external_encoding();
+        default_ext = 1;
     }
-    if (ext == rb_ascii8bit_encoding()) {
-	/* If external is ASCII-8BIT, no transcoding */
-	intern = NULL;
+    if (rb_is_ascii8bit_enc(ext)) {
+        /* If external is ASCII-8BIT, no transcoding */
+        intern = NULL;
     }
     else if (intern == NULL) {
-	intern = rb_default_internal_encoding();
+        intern = rb_default_internal_encoding();
     }
     if (intern == NULL || intern == (rb_encoding *)Qnil ||
-	(!(fmode & FMODE_SETENC_BY_BOM) && (intern == ext))) {
-	/* No internal encoding => use external + no transcoding */
-	*enc = (default_ext && intern != ext) ? NULL : ext;
-	*enc2 = NULL;
+        (!(fmode & FMODE_SETENC_BY_BOM) && (intern == ext))) {
+        /* No internal encoding => use external + no transcoding */
+        *enc = (default_ext && intern != ext) ? NULL : ext;
+        *enc2 = NULL;
     }
     else {
-	*enc = intern;
-	*enc2 = ext;
+        *enc = intern;
+        *enc2 = ext;
     }
 }
 
@@ -6266,7 +6614,7 @@ unsupported_encoding(const char *name, rb_encoding *enc)
 
 static void
 parse_mode_enc(const char *estr, rb_encoding *estr_enc,
-	       rb_encoding **enc_p, rb_encoding **enc2_p, int *fmode_p)
+               rb_encoding **enc_p, rb_encoding **enc2_p, int *fmode_p)
 {
     const char *p;
     char encname[ENCODING_MAXNAMELEN+1];
@@ -6280,53 +6628,53 @@ parse_mode_enc(const char *estr, rb_encoding *estr_enc,
     p = strrchr(estr, ':');
     len = p ? (p++ - estr) : (long)strlen(estr);
     if ((fmode & FMODE_SETENC_BY_BOM) || io_encname_bom_p(estr, len)) {
-	estr += bom_prefix_len;
-	len -= bom_prefix_len;
-	if (!STRNCASECMP(estr, utf_prefix, utf_prefix_len)) {
-	    fmode |= FMODE_SETENC_BY_BOM;
-	}
-	else {
-	    rb_enc_warn(estr_enc, "BOM with non-UTF encoding %s is nonsense", estr);
-	    fmode &= ~FMODE_SETENC_BY_BOM;
-	}
+        estr += bom_prefix_len;
+        len -= bom_prefix_len;
+        if (!STRNCASECMP(estr, utf_prefix, utf_prefix_len)) {
+            fmode |= FMODE_SETENC_BY_BOM;
+        }
+        else {
+            rb_enc_warn(estr_enc, "BOM with non-UTF encoding %s is nonsense", estr);
+            fmode &= ~FMODE_SETENC_BY_BOM;
+        }
     }
     if (len == 0 || len > ENCODING_MAXNAMELEN) {
-	idx = -1;
+        idx = -1;
     }
     else {
-	if (p) {
-	    memcpy(encname, estr, len);
-	    encname[len] = '\0';
-	    estr = encname;
-	}
-	idx = rb_enc_find_index(estr);
+        if (p) {
+            memcpy(encname, estr, len);
+            encname[len] = '\0';
+            estr = encname;
+        }
+        idx = rb_enc_find_index(estr);
     }
     if (fmode_p) *fmode_p = fmode;
 
     if (idx >= 0)
-	ext_enc = rb_enc_from_index(idx);
+        ext_enc = rb_enc_from_index(idx);
     else {
-	if (idx != -2)
-	    unsupported_encoding(estr, estr_enc);
-	ext_enc = NULL;
+        if (idx != -2)
+            unsupported_encoding(estr, estr_enc);
+        ext_enc = NULL;
     }
 
     int_enc = NULL;
     if (p) {
-	if (*p == '-' && *(p+1) == '\0') {
-	    /* Special case - "-" => no transcoding */
-	    int_enc = (rb_encoding *)Qnil;
-	}
-	else {
-	    idx2 = rb_enc_find_index(p);
-	    if (idx2 < 0)
-		unsupported_encoding(p, estr_enc);
-	    else if (!(fmode & FMODE_SETENC_BY_BOM) && (idx2 == idx)) {
-		int_enc = (rb_encoding *)Qnil;
-	    }
-	    else
-		int_enc = rb_enc_from_index(idx2);
-	}
+        if (*p == '-' && *(p+1) == '\0') {
+            /* Special case - "-" => no transcoding */
+            int_enc = (rb_encoding *)Qnil;
+        }
+        else {
+            idx2 = rb_enc_find_index(p);
+            if (idx2 < 0)
+                unsupported_encoding(p, estr_enc);
+            else if (!(fmode & FMODE_SETENC_BY_BOM) && (idx2 == idx)) {
+                int_enc = (rb_encoding *)Qnil;
+            }
+            else
+                int_enc = rb_enc_from_index(idx2);
+        }
     }
 
     rb_io_ext_int_to_encs(ext_enc, int_enc, enc_p, enc2_p, fmode);
@@ -6341,62 +6689,62 @@ rb_io_extract_encoding_option(VALUE opt, rb_encoding **enc_p, rb_encoding **enc2
     rb_encoding *intencoding = NULL;
 
     if (!NIL_P(opt)) {
-	VALUE v;
-	v = rb_hash_lookup2(opt, sym_encoding, Qnil);
-	if (v != Qnil) encoding = v;
-	v = rb_hash_lookup2(opt, sym_extenc, Qundef);
-	if (v != Qnil) extenc = v;
-	v = rb_hash_lookup2(opt, sym_intenc, Qundef);
-	if (v != Qundef) intenc = v;
-    }
-    if ((extenc != Qundef || intenc != Qundef) && !NIL_P(encoding)) {
-	if (!NIL_P(ruby_verbose)) {
-	    int idx = rb_to_encoding_index(encoding);
-	    if (idx >= 0) encoding = rb_enc_from_encoding(rb_enc_from_index(idx));
-	    rb_warn("Ignoring encoding parameter '%"PRIsVALUE"': %s_encoding is used",
-		    encoding, extenc == Qundef ? "internal" : "external");
-	}
-	encoding = Qnil;
-    }
-    if (extenc != Qundef && !NIL_P(extenc)) {
-	extencoding = rb_to_encoding(extenc);
-    }
-    if (intenc != Qundef) {
-	if (NIL_P(intenc)) {
-	    /* internal_encoding: nil => no transcoding */
-	    intencoding = (rb_encoding *)Qnil;
-	}
-	else if (!NIL_P(tmp = rb_check_string_type(intenc))) {
-	    char *p = StringValueCStr(tmp);
-
-	    if (*p == '-' && *(p+1) == '\0') {
-		/* Special case - "-" => no transcoding */
-		intencoding = (rb_encoding *)Qnil;
-	    }
-	    else {
-		intencoding = rb_to_encoding(intenc);
-	    }
-	}
-	else {
-	    intencoding = rb_to_encoding(intenc);
-	}
-	if (extencoding == intencoding) {
-	    intencoding = (rb_encoding *)Qnil;
-	}
+        VALUE v;
+        v = rb_hash_lookup2(opt, sym_encoding, Qnil);
+        if (v != Qnil) encoding = v;
+        v = rb_hash_lookup2(opt, sym_extenc, Qundef);
+        if (v != Qnil) extenc = v;
+        v = rb_hash_lookup2(opt, sym_intenc, Qundef);
+        if (!UNDEF_P(v)) intenc = v;
+    }
+    if ((!UNDEF_P(extenc) || !UNDEF_P(intenc)) && !NIL_P(encoding)) {
+        if (!NIL_P(ruby_verbose)) {
+            int idx = rb_to_encoding_index(encoding);
+            if (idx >= 0) encoding = rb_enc_from_encoding(rb_enc_from_index(idx));
+            rb_warn("Ignoring encoding parameter '%"PRIsVALUE"': %s_encoding is used",
+                    encoding, UNDEF_P(extenc) ? "internal" : "external");
+        }
+        encoding = Qnil;
+    }
+    if (!UNDEF_P(extenc) && !NIL_P(extenc)) {
+        extencoding = rb_to_encoding(extenc);
+    }
+    if (!UNDEF_P(intenc)) {
+        if (NIL_P(intenc)) {
+            /* internal_encoding: nil => no transcoding */
+            intencoding = (rb_encoding *)Qnil;
+        }
+        else if (!NIL_P(tmp = rb_check_string_type(intenc))) {
+            char *p = StringValueCStr(tmp);
+
+            if (*p == '-' && *(p+1) == '\0') {
+                /* Special case - "-" => no transcoding */
+                intencoding = (rb_encoding *)Qnil;
+            }
+            else {
+                intencoding = rb_to_encoding(intenc);
+            }
+        }
+        else {
+            intencoding = rb_to_encoding(intenc);
+        }
+        if (extencoding == intencoding) {
+            intencoding = (rb_encoding *)Qnil;
+        }
     }
     if (!NIL_P(encoding)) {
-	extracted = 1;
-	if (!NIL_P(tmp = rb_check_string_type(encoding))) {
-	    parse_mode_enc(StringValueCStr(tmp), rb_enc_get(tmp),
-			   enc_p, enc2_p, fmode_p);
-	}
-	else {
-	    rb_io_ext_int_to_encs(rb_to_encoding(encoding), NULL, enc_p, enc2_p, 0);
-	}
-    }
-    else if (extenc != Qundef || intenc != Qundef) {
         extracted = 1;
-	rb_io_ext_int_to_encs(extencoding, intencoding, enc_p, enc2_p, 0);
+        if (!NIL_P(tmp = rb_check_string_type(encoding))) {
+            parse_mode_enc(StringValueCStr(tmp), rb_enc_get(tmp),
+                           enc_p, enc2_p, fmode_p);
+        }
+        else {
+            rb_io_ext_int_to_encs(rb_to_encoding(encoding), NULL, enc_p, enc2_p, 0);
+        }
+    }
+    else if (!UNDEF_P(extenc) || !UNDEF_P(intenc)) {
+        extracted = 1;
+        rb_io_ext_int_to_encs(extencoding, intencoding, enc_p, enc2_p, 0);
     }
     return extracted;
 }
@@ -6415,17 +6763,17 @@ validate_enc_binmode(int *fmode_p, int ecflags, rb_encoding *enc, rb_encoding *e
         rb_raise(rb_eArgError, "ASCII incompatible encoding needs binmode");
 
     if ((fmode & FMODE_BINMODE) && (ecflags & ECONV_NEWLINE_DECORATOR_MASK)) {
-	rb_raise(rb_eArgError, "newline decorator with binary mode");
+        rb_raise(rb_eArgError, "newline decorator with binary mode");
     }
     if (!(fmode & FMODE_BINMODE) &&
-	(DEFAULT_TEXTMODE || (ecflags & ECONV_NEWLINE_DECORATOR_MASK))) {
-	fmode |= FMODE_TEXTMODE;
-	*fmode_p = fmode;
+        (DEFAULT_TEXTMODE || (ecflags & ECONV_NEWLINE_DECORATOR_MASK))) {
+        fmode |= FMODE_TEXTMODE;
+        *fmode_p = fmode;
     }
 #if !DEFAULT_TEXTMODE
     else if (!(ecflags & ECONV_NEWLINE_DECORATOR_MASK)) {
-	fmode &= ~FMODE_TEXTMODE;
-	*fmode_p = fmode;
+        fmode &= ~FMODE_TEXTMODE;
+        *fmode_p = fmode;
     }
 #endif
 }
@@ -6434,28 +6782,28 @@ static void
 extract_binmode(VALUE opthash, int *fmode)
 {
     if (!NIL_P(opthash)) {
-	VALUE v;
-	v = rb_hash_aref(opthash, sym_textmode);
-	if (!NIL_P(v)) {
-	    if (*fmode & FMODE_TEXTMODE)
-		rb_raise(rb_eArgError, "textmode specified twice");
-	    if (*fmode & FMODE_BINMODE)
-		rb_raise(rb_eArgError, "both textmode and binmode specified");
-	    if (RTEST(v))
-		*fmode |= FMODE_TEXTMODE;
-	}
-	v = rb_hash_aref(opthash, sym_binmode);
-	if (!NIL_P(v)) {
-	    if (*fmode & FMODE_BINMODE)
-		rb_raise(rb_eArgError, "binmode specified twice");
-	    if (*fmode & FMODE_TEXTMODE)
-		rb_raise(rb_eArgError, "both textmode and binmode specified");
-	    if (RTEST(v))
-		*fmode |= FMODE_BINMODE;
-	}
-
-	if ((*fmode & FMODE_BINMODE) && (*fmode & FMODE_TEXTMODE))
-	    rb_raise(rb_eArgError, "both textmode and binmode specified");
+        VALUE v;
+        v = rb_hash_aref(opthash, sym_textmode);
+        if (!NIL_P(v)) {
+            if (*fmode & FMODE_TEXTMODE)
+                rb_raise(rb_eArgError, "textmode specified twice");
+            if (*fmode & FMODE_BINMODE)
+                rb_raise(rb_eArgError, "both textmode and binmode specified");
+            if (RTEST(v))
+                *fmode |= FMODE_TEXTMODE;
+        }
+        v = rb_hash_aref(opthash, sym_binmode);
+        if (!NIL_P(v)) {
+            if (*fmode & FMODE_BINMODE)
+                rb_raise(rb_eArgError, "binmode specified twice");
+            if (*fmode & FMODE_TEXTMODE)
+                rb_raise(rb_eArgError, "both textmode and binmode specified");
+            if (RTEST(v))
+                *fmode |= FMODE_BINMODE;
+        }
+
+        if ((*fmode & FMODE_BINMODE) && (*fmode & FMODE_TEXTMODE))
+            rb_raise(rb_eArgError, "both textmode and binmode specified");
     }
 }
 
@@ -6498,24 +6846,24 @@ rb_io_extract_modeenc(VALUE *vmode_p, VALUE *vperm_p, VALUE opthash,
             has_enc = 1;
             parse_mode_enc(p+1, rb_enc_get(vmode), &enc, &enc2, &fmode);
         }
-	else {
-	    rb_encoding *e;
+        else {
+            rb_encoding *e;
 
-	    e = (fmode & FMODE_BINMODE) ? rb_ascii8bit_encoding() : NULL;
-	    rb_io_ext_int_to_encs(e, NULL, &enc, &enc2, fmode);
-	}
+            e = (fmode & FMODE_BINMODE) ? rb_ascii8bit_encoding() : NULL;
+            rb_io_ext_int_to_encs(e, NULL, &enc, &enc2, fmode);
+        }
     }
 
     if (NIL_P(opthash)) {
-	ecflags = (fmode & FMODE_READABLE) ?
-	    MODE_BTMODE(ECONV_DEFAULT_NEWLINE_DECORATOR,
-			0, ECONV_UNIVERSAL_NEWLINE_DECORATOR) : 0;
+        ecflags = (fmode & FMODE_READABLE) ?
+            MODE_BTMODE(ECONV_DEFAULT_NEWLINE_DECORATOR,
+                        0, ECONV_UNIVERSAL_NEWLINE_DECORATOR) : 0;
 #ifdef TEXTMODE_NEWLINE_DECORATOR_ON_WRITE
-	ecflags |= (fmode & FMODE_WRITABLE) ?
-	    MODE_BTMODE(TEXTMODE_NEWLINE_DECORATOR_ON_WRITE,
-			0, TEXTMODE_NEWLINE_DECORATOR_ON_WRITE) : 0;
+        ecflags |= (fmode & FMODE_WRITABLE) ?
+            MODE_BTMODE(TEXTMODE_NEWLINE_DECORATOR_ON_WRITE,
+                        0, TEXTMODE_NEWLINE_DECORATOR_ON_WRITE) : 0;
 #endif
-	SET_UNIVERSAL_NEWLINE_DECORATOR_IF_ENC2(enc2, ecflags);
+        SET_UNIVERSAL_NEWLINE_DECORATOR_IF_ENC2(enc2, ecflags);
         ecopts = Qnil;
         if (fmode & FMODE_BINMODE) {
 #ifdef O_BINARY
@@ -6531,57 +6879,57 @@ rb_io_extract_modeenc(VALUE *vmode_p, VALUE *vperm_p, VALUE opthash,
 #endif
     }
     else {
-	VALUE v;
-	if (!has_vmode) {
-	    v = rb_hash_aref(opthash, sym_mode);
-	    if (!NIL_P(v)) {
-		if (!NIL_P(vmode)) {
-		    rb_raise(rb_eArgError, "mode specified twice");
-		}
-		has_vmode = 1;
-		vmode = v;
-		goto vmode_handle;
-	    }
-	}
-	v = rb_hash_aref(opthash, sym_flags);
-	if (!NIL_P(v)) {
-	    v = rb_to_int(v);
-	    oflags |= NUM2INT(v);
-	    vmode = INT2NUM(oflags);
-	    fmode = rb_io_oflags_fmode(oflags);
-	}
-	extract_binmode(opthash, &fmode);
-	if (fmode & FMODE_BINMODE) {
+        VALUE v;
+        if (!has_vmode) {
+            v = rb_hash_aref(opthash, sym_mode);
+            if (!NIL_P(v)) {
+                if (!NIL_P(vmode)) {
+                    rb_raise(rb_eArgError, "mode specified twice");
+                }
+                has_vmode = 1;
+                vmode = v;
+                goto vmode_handle;
+            }
+        }
+        v = rb_hash_aref(opthash, sym_flags);
+        if (!NIL_P(v)) {
+            v = rb_to_int(v);
+            oflags |= NUM2INT(v);
+            vmode = INT2NUM(oflags);
+            fmode = rb_io_oflags_fmode(oflags);
+        }
+        extract_binmode(opthash, &fmode);
+        if (fmode & FMODE_BINMODE) {
 #ifdef O_BINARY
             oflags |= O_BINARY;
 #endif
-	    if (!has_enc)
-		rb_io_ext_int_to_encs(rb_ascii8bit_encoding(), NULL, &enc, &enc2, fmode);
-	}
+            if (!has_enc)
+                rb_io_ext_int_to_encs(rb_ascii8bit_encoding(), NULL, &enc, &enc2, fmode);
+        }
 #if DEFAULT_TEXTMODE
-	else if (NIL_P(vmode)) {
-	    fmode |= DEFAULT_TEXTMODE;
-	}
-#endif
-	v = rb_hash_aref(opthash, sym_perm);
-	if (!NIL_P(v)) {
-	    if (vperm_p) {
-		if (!NIL_P(*vperm_p)) {
-		    rb_raise(rb_eArgError, "perm specified twice");
-		}
-		*vperm_p = v;
-	    }
-	    else {
-		/* perm no use, just ignore */
-	    }
-	}
-	ecflags = (fmode & FMODE_READABLE) ?
-	    MODE_BTMODE(ECONV_DEFAULT_NEWLINE_DECORATOR,
-			0, ECONV_UNIVERSAL_NEWLINE_DECORATOR) : 0;
+        else if (NIL_P(vmode)) {
+            fmode |= DEFAULT_TEXTMODE;
+        }
+#endif
+        v = rb_hash_aref(opthash, sym_perm);
+        if (!NIL_P(v)) {
+            if (vperm_p) {
+                if (!NIL_P(*vperm_p)) {
+                    rb_raise(rb_eArgError, "perm specified twice");
+                }
+                *vperm_p = v;
+            }
+            else {
+                /* perm no use, just ignore */
+            }
+        }
+        ecflags = (fmode & FMODE_READABLE) ?
+            MODE_BTMODE(ECONV_DEFAULT_NEWLINE_DECORATOR,
+                        0, ECONV_UNIVERSAL_NEWLINE_DECORATOR) : 0;
 #ifdef TEXTMODE_NEWLINE_DECORATOR_ON_WRITE
-	ecflags |= (fmode & FMODE_WRITABLE) ?
-	    MODE_BTMODE(TEXTMODE_NEWLINE_DECORATOR_ON_WRITE,
-			0, TEXTMODE_NEWLINE_DECORATOR_ON_WRITE) : 0;
+        ecflags |= (fmode & FMODE_WRITABLE) ?
+            MODE_BTMODE(TEXTMODE_NEWLINE_DECORATOR_ON_WRITE,
+                        0, TEXTMODE_NEWLINE_DECORATOR_ON_WRITE) : 0;
 #endif
 
         if (rb_io_extract_encoding_option(opthash, &enc, &enc2, &fmode)) {
@@ -6589,8 +6937,8 @@ rb_io_extract_modeenc(VALUE *vmode_p, VALUE *vperm_p, VALUE opthash,
                 rb_raise(rb_eArgError, "encoding specified twice");
             }
         }
-	SET_UNIVERSAL_NEWLINE_DECORATOR_IF_ENC2(enc2, ecflags);
-	ecflags = rb_econv_prepare_options(opthash, &ecopts, ecflags);
+        SET_UNIVERSAL_NEWLINE_DECORATOR_IF_ENC2(enc2, ecflags);
+        ecflags = rb_econv_prepare_options(opthash, &ecopts, ecflags);
     }
 
     validate_enc_binmode(&fmode, ecflags, enc, enc2);
@@ -6642,13 +6990,13 @@ rb_sysopen(VALUE fname, int oflags, mode_t perm)
 
     fd = rb_sysopen_internal(&data);
     if (fd < 0) {
-	int e = errno;
-	if (rb_gc_for_fd(e)) {
-	    fd = rb_sysopen_internal(&data);
-	}
-	if (fd < 0) {
-	    rb_syserr_fail_path(e, fname);
-	}
+        int e = errno;
+        if (rb_gc_for_fd(e)) {
+            fd = rb_sysopen_internal(&data);
+        }
+        if (fd < 0) {
+            rb_syserr_fail_path(e, fname);
+        }
     }
     return fd;
 }
@@ -6663,32 +7011,32 @@ rb_fdopen(int fd, const char *modestr)
 #endif
     file = fdopen(fd, modestr);
     if (!file) {
-	int e = errno;
+        int e = errno;
 #if defined(__sun)
-	if (e == 0) {
-	    rb_gc();
-	    errno = 0;
-	    file = fdopen(fd, modestr);
-	}
-	else
-#endif
-	if (rb_gc_for_fd(e)) {
-	    file = fdopen(fd, modestr);
-	}
-	if (!file) {
+        if (e == 0) {
+            rb_gc();
+            errno = 0;
+            file = fdopen(fd, modestr);
+        }
+        else
+#endif
+        if (rb_gc_for_fd(e)) {
+            file = fdopen(fd, modestr);
+        }
+        if (!file) {
 #ifdef _WIN32
-	    if (e == 0) e = EINVAL;
+            if (e == 0) e = EINVAL;
 #elif defined(__sun)
-	    if (e == 0) e = EMFILE;
+            if (e == 0) e = EMFILE;
 #endif
-	    rb_syserr_fail(e, 0);
-	}
+            rb_syserr_fail(e, 0);
+        }
     }
 
     /* xxx: should be _IONBF?  A buffer in FILE may have trouble. */
 #ifdef USE_SETVBUF
     if (setvbuf(file, NULL, _IOFBF, 0) != 0)
-	rb_warn("setvbuf() can't be honoured (fd=%d)", fd);
+        rb_warn("setvbuf() can't be honoured (fd=%d)", fd);
 #endif
     return file;
 }
@@ -6716,53 +7064,53 @@ io_strip_bom(VALUE io)
     if (NIL_P(b1 = rb_io_getbyte(io))) return 0;
     switch (b1) {
       case INT2FIX(0xEF):
-	if (NIL_P(b2 = rb_io_getbyte(io))) break;
-	if (b2 == INT2FIX(0xBB) && !NIL_P(b3 = rb_io_getbyte(io))) {
-	    if (b3 == INT2FIX(0xBF)) {
-		return rb_utf8_encindex();
-	    }
-	    rb_io_ungetbyte(io, b3);
-	}
-	rb_io_ungetbyte(io, b2);
-	break;
+        if (NIL_P(b2 = rb_io_getbyte(io))) break;
+        if (b2 == INT2FIX(0xBB) && !NIL_P(b3 = rb_io_getbyte(io))) {
+            if (b3 == INT2FIX(0xBF)) {
+                return rb_utf8_encindex();
+            }
+            rb_io_ungetbyte(io, b3);
+        }
+        rb_io_ungetbyte(io, b2);
+        break;
 
       case INT2FIX(0xFE):
-	if (NIL_P(b2 = rb_io_getbyte(io))) break;
-	if (b2 == INT2FIX(0xFF)) {
-	    return ENCINDEX_UTF_16BE;
-	}
-	rb_io_ungetbyte(io, b2);
-	break;
+        if (NIL_P(b2 = rb_io_getbyte(io))) break;
+        if (b2 == INT2FIX(0xFF)) {
+            return ENCINDEX_UTF_16BE;
+        }
+        rb_io_ungetbyte(io, b2);
+        break;
 
       case INT2FIX(0xFF):
-	if (NIL_P(b2 = rb_io_getbyte(io))) break;
-	if (b2 == INT2FIX(0xFE)) {
-	    b3 = rb_io_getbyte(io);
-	    if (b3 == INT2FIX(0) && !NIL_P(b4 = rb_io_getbyte(io))) {
-		if (b4 == INT2FIX(0)) {
-		    return ENCINDEX_UTF_32LE;
-		}
-		rb_io_ungetbyte(io, b4);
-	    }
+        if (NIL_P(b2 = rb_io_getbyte(io))) break;
+        if (b2 == INT2FIX(0xFE)) {
+            b3 = rb_io_getbyte(io);
+            if (b3 == INT2FIX(0) && !NIL_P(b4 = rb_io_getbyte(io))) {
+                if (b4 == INT2FIX(0)) {
+                    return ENCINDEX_UTF_32LE;
+                }
+                rb_io_ungetbyte(io, b4);
+            }
             rb_io_ungetbyte(io, b3);
             return ENCINDEX_UTF_16LE;
-	}
-	rb_io_ungetbyte(io, b2);
-	break;
+        }
+        rb_io_ungetbyte(io, b2);
+        break;
 
       case INT2FIX(0):
-	if (NIL_P(b2 = rb_io_getbyte(io))) break;
-	if (b2 == INT2FIX(0) && !NIL_P(b3 = rb_io_getbyte(io))) {
-	    if (b3 == INT2FIX(0xFE) && !NIL_P(b4 = rb_io_getbyte(io))) {
-		if (b4 == INT2FIX(0xFF)) {
-		    return ENCINDEX_UTF_32BE;
-		}
-		rb_io_ungetbyte(io, b4);
-	    }
-	    rb_io_ungetbyte(io, b3);
-	}
-	rb_io_ungetbyte(io, b2);
-	break;
+        if (NIL_P(b2 = rb_io_getbyte(io))) break;
+        if (b2 == INT2FIX(0) && !NIL_P(b3 = rb_io_getbyte(io))) {
+            if (b3 == INT2FIX(0xFE) && !NIL_P(b4 = rb_io_getbyte(io))) {
+                if (b4 == INT2FIX(0xFF)) {
+                    return ENCINDEX_UTF_32BE;
+                }
+                rb_io_ungetbyte(io, b4);
+            }
+            rb_io_ungetbyte(io, b3);
+        }
+        rb_io_ungetbyte(io, b2);
+        break;
     }
     rb_io_ungetbyte(io, b1);
     return 0;
@@ -6782,27 +7130,27 @@ io_set_encoding_by_bom(VALUE io)
                         rb_io_internal_encoding(io), Qnil);
     }
     else {
-	fptr->encs.enc2 = NULL;
+        fptr->encs.enc2 = NULL;
     }
     return extenc;
 }
 
 static VALUE
 rb_file_open_generic(VALUE io, VALUE filename, int oflags, int fmode,
-		     const convconfig_t *convconfig, mode_t perm)
+                     const convconfig_t *convconfig, mode_t perm)
 {
     VALUE pathv;
     rb_io_t *fptr;
     convconfig_t cc;
     if (!convconfig) {
-	/* Set to default encodings */
-	rb_io_ext_int_to_encs(NULL, NULL, &cc.enc, &cc.enc2, fmode);
+        /* Set to default encodings */
+        rb_io_ext_int_to_encs(NULL, NULL, &cc.enc, &cc.enc2, fmode);
         cc.ecflags = 0;
         cc.ecopts = Qnil;
         convconfig = &cc;
     }
     validate_enc_binmode(&fmode, convconfig->ecflags,
-			 convconfig->enc, convconfig->enc2);
+                         convconfig->enc, convconfig->enc2);
 
     MakeOpenFile(io, fptr);
     fptr->mode = fmode;
@@ -6831,16 +7179,16 @@ rb_file_open_internal(VALUE io, VALUE filename, const char *modestr)
 
     if (p) {
         parse_mode_enc(p+1, rb_usascii_encoding(),
-		       &convconfig.enc, &convconfig.enc2, &fmode);
+                       &convconfig.enc, &convconfig.enc2, &fmode);
         convconfig.ecflags = 0;
         convconfig.ecopts = Qnil;
     }
     else {
-	rb_encoding *e;
-	/* Set to default encodings */
+        rb_encoding *e;
+        /* Set to default encodings */
 
-	e = (fmode & FMODE_BINMODE) ? rb_ascii8bit_encoding() : NULL;
-	rb_io_ext_int_to_encs(e, NULL, &convconfig.enc, &convconfig.enc2, fmode);
+        e = (fmode & FMODE_BINMODE) ? rb_ascii8bit_encoding() : NULL;
+        rb_io_ext_int_to_encs(e, NULL, &convconfig.enc, &convconfig.enc2, fmode);
         convconfig.ecflags = 0;
         convconfig.ecopts = Qnil;
     }
@@ -6889,12 +7237,12 @@ pipe_del_fptr(rb_io_t *fptr)
     struct pipe_list *tmp;
 
     while ((tmp = *prev) != 0) {
-	if (tmp->fptr == fptr) {
-	    *prev = tmp->next;
-	    free(tmp);
-	    return;
-	}
-	prev = &tmp->next;
+        if (tmp->fptr == fptr) {
+            *prev = tmp->next;
+            free(tmp);
+            return;
+        }
+        prev = &tmp->next;
     }
 }
 
@@ -6906,9 +7254,9 @@ pipe_atexit(void)
     struct pipe_list *tmp;
 
     while (list) {
-	tmp = list->next;
-	rb_io_fptr_finalize(list->fptr);
-	list = tmp;
+        tmp = list->next;
+        rb_io_fptr_finalize(list->fptr);
+        list = tmp;
     }
 }
 #endif
@@ -6944,14 +7292,14 @@ fptr_copy_finalizer(rb_io_t *fptr, const rb_io_t *orig)
 
 #if defined(__CYGWIN__) || !defined(HAVE_WORKING_FORK)
     if (old_finalize != pipe_finalize) {
-	struct pipe_list *list;
-	for (list = pipe_list; list; list = list->next) {
-	    if (list->fptr == fptr) break;
-	}
-	if (!list) pipe_add_fptr(fptr);
+        struct pipe_list *list;
+        for (list = pipe_list; list; list = list->next) {
+            if (list->fptr == fptr) break;
+        }
+        if (!list) pipe_add_fptr(fptr);
     }
     else {
-	pipe_del_fptr(fptr);
+        pipe_del_fptr(fptr);
     }
 #endif
 }
@@ -7102,15 +7450,15 @@ rb_close_before_exec(int lowfd, int maxhint, VALUE noclose_fds)
         if (!NIL_P(noclose_fds) &&
             RTEST(rb_hash_lookup(noclose_fds, INT2FIX(fd)))) /* async-signal-safe */
             continue;
-	ret = fcntl(fd, F_GETFD); /* async-signal-safe */
-	if (ret != -1 && !(ret & FD_CLOEXEC)) {
+        ret = fcntl(fd, F_GETFD); /* async-signal-safe */
+        if (ret != -1 && !(ret & FD_CLOEXEC)) {
             fcntl(fd, F_SETFD, ret|FD_CLOEXEC); /* async-signal-safe */
         }
 # define CONTIGUOUS_CLOSED_FDS 20
         if (ret != -1) {
-	    if (max < fd + CONTIGUOUS_CLOSED_FDS)
-		max = fd + CONTIGUOUS_CLOSED_FDS;
-	}
+            if (max < fd + CONTIGUOUS_CLOSED_FDS)
+                max = fd + CONTIGUOUS_CLOSED_FDS;
+        }
     }
 #endif
 }
@@ -7140,7 +7488,7 @@ char *rb_execarg_commandline(const struct rb_execarg *eargp, VALUE *prog);
 #ifndef __EMSCRIPTEN__
 static VALUE
 pipe_open(VALUE execarg_obj, const char *modestr, int fmode,
-	  const convconfig_t *convconfig)
+          const convconfig_t *convconfig)
 {
     struct rb_execarg *eargp = NIL_P(execarg_obj) ? NULL : rb_execarg_get(execarg_obj);
     VALUE prog = eargp ? (eargp->use_shell ? eargp->invoke.sh.shell_script : eargp->invoke.cmd.command_name) : Qfalse ;
@@ -7161,12 +7509,12 @@ pipe_open(VALUE execarg_obj, const char *modestr, int fmode,
 #if defined(HAVE_SPAWNV)
 # if defined(HAVE_SPAWNVE)
 #   define DO_SPAWN(cmd, args, envp) ((args) ? \
-				      spawnve(P_NOWAIT, (cmd), (args), (envp)) : \
-				      spawne(P_NOWAIT, (cmd), (envp)))
+                                      spawnve(P_NOWAIT, (cmd), (args), (envp)) : \
+                                      spawne(P_NOWAIT, (cmd), (envp)))
 # else
 #   define DO_SPAWN(cmd, args, envp) ((args) ? \
-				      spawnv(P_NOWAIT, (cmd), (args)) : \
-				      spawn(P_NOWAIT, (cmd)))
+                                      spawnv(P_NOWAIT, (cmd), (args)) : \
+                                      spawn(P_NOWAIT, (cmd)))
 # endif
 # if !defined(HAVE_WORKING_FORK)
     char **args = NULL;
@@ -7213,19 +7561,19 @@ pipe_open(VALUE execarg_obj, const char *modestr, int fmode,
             rb_execarg_addopt(execarg_obj, INT2FIX(0), INT2FIX(arg.write_pair[0]));
             rb_execarg_addopt(execarg_obj, INT2FIX(1), INT2FIX(arg.pair[1]));
         }
-	break;
+        break;
       case FMODE_READABLE:
         if (rb_pipe(arg.pair) < 0)
             rb_sys_fail_str(prog);
         if (eargp)
             rb_execarg_addopt(execarg_obj, INT2FIX(1), INT2FIX(arg.pair[1]));
-	break;
+        break;
       case FMODE_WRITABLE:
         if (rb_pipe(arg.pair) < 0)
             rb_sys_fail_str(prog);
         if (eargp)
             rb_execarg_addopt(execarg_obj, INT2FIX(0), INT2FIX(arg.pair[0]));
-	break;
+        break;
       default:
         rb_sys_fail_str(prog);
     }
@@ -7241,59 +7589,59 @@ pipe_open(VALUE execarg_obj, const char *modestr, int fmode,
         }
 
 # if defined(HAVE_WORKING_FORK)
-	pid = rb_fork_async_signal_safe(&status, popen_exec, &arg, arg.eargp->redirect_fds, errmsg, sizeof(errmsg));
+        pid = rb_fork_async_signal_safe(&status, popen_exec, &arg, arg.eargp->redirect_fds, errmsg, sizeof(errmsg));
 # else
-	rb_execarg_run_options(eargp, sargp, NULL, 0);
+        rb_execarg_run_options(eargp, sargp, NULL, 0);
 #   if defined(HAVE_SPAWNVE)
-	if (eargp->envp_str) envp = (char **)RSTRING_PTR(eargp->envp_str);
+        if (eargp->envp_str) envp = (char **)RSTRING_PTR(eargp->envp_str);
 #   endif
         while ((pid = DO_SPAWN(cmd, args, envp)) < 0) {
-	    /* exec failed */
-	    switch (e = errno) {
-	      case EAGAIN:
+            /* exec failed */
+            switch (e = errno) {
+              case EAGAIN:
 #   if EWOULDBLOCK != EAGAIN
-	      case EWOULDBLOCK:
+              case EWOULDBLOCK:
 #   endif
-		rb_thread_sleep(1);
-		continue;
-	    }
-	    break;
-	}
-	if (eargp)
-	    rb_execarg_run_options(sargp, NULL, NULL, 0);
+                rb_thread_sleep(1);
+                continue;
+            }
+            break;
+        }
+        if (eargp)
+            rb_execarg_run_options(sargp, NULL, NULL, 0);
 # endif
         rb_execarg_parent_end(execarg_obj);
     }
     else {
 # if defined(HAVE_WORKING_FORK)
-	pid = rb_call_proc__fork();
-	if (pid == 0) {		/* child */
-	    popen_redirect(&arg);
-	    rb_io_synchronized(RFILE(orig_stdout)->fptr);
-	    rb_io_synchronized(RFILE(orig_stderr)->fptr);
-	    return Qnil;
-	}
+        pid = rb_call_proc__fork();
+        if (pid == 0) {		/* child */
+            popen_redirect(&arg);
+            rb_io_synchronized(RFILE(orig_stdout)->fptr);
+            rb_io_synchronized(RFILE(orig_stderr)->fptr);
+            return Qnil;
+        }
 # else
-	rb_notimplement();
+        rb_notimplement();
 # endif
     }
 
     /* parent */
     if (pid < 0) {
 # if defined(HAVE_WORKING_FORK)
-	e = errno;
+        e = errno;
 # endif
-	close(arg.pair[0]);
-	close(arg.pair[1]);
+        close(arg.pair[0]);
+        close(arg.pair[1]);
         if ((fmode & (FMODE_READABLE|FMODE_WRITABLE)) == (FMODE_READABLE|FMODE_WRITABLE)) {
             close(arg.write_pair[0]);
             close(arg.write_pair[1]);
         }
 # if defined(HAVE_WORKING_FORK)
         if (errmsg[0])
-	    rb_syserr_fail(e, errmsg);
+            rb_syserr_fail(e, errmsg);
 # endif
-	rb_syserr_fail_str(e, prog);
+        rb_syserr_fail_str(e, prog);
     }
     if ((fmode & FMODE_READABLE) && (fmode & FMODE_WRITABLE)) {
         close(arg.pair[1]);
@@ -7312,14 +7660,14 @@ pipe_open(VALUE execarg_obj, const char *modestr, int fmode,
 #else
     cmd = rb_execarg_commandline(eargp, &prog);
     if (!NIL_P(execarg_obj)) {
-	rb_execarg_parent_start(execarg_obj);
-	rb_execarg_run_options(eargp, sargp, NULL, 0);
+        rb_execarg_parent_start(execarg_obj);
+        rb_execarg_run_options(eargp, sargp, NULL, 0);
     }
     fp = popen(cmd, modestr);
     e = errno;
     if (eargp) {
         rb_execarg_parent_end(execarg_obj);
-	rb_execarg_run_options(sargp, NULL, NULL, 0);
+        rb_execarg_run_options(sargp, NULL, NULL, 0);
     }
     if (!fp) rb_syserr_fail_path(e, prog);
     fd = fileno(fp);
@@ -7333,19 +7681,19 @@ pipe_open(VALUE execarg_obj, const char *modestr, int fmode,
     if (convconfig) {
         fptr->encs = *convconfig;
 #if RUBY_CRLF_ENVIRONMENT
-	if (fptr->encs.ecflags & ECONV_DEFAULT_NEWLINE_DECORATOR) {
-	    fptr->encs.ecflags |= ECONV_UNIVERSAL_NEWLINE_DECORATOR;
-	}
+        if (fptr->encs.ecflags & ECONV_DEFAULT_NEWLINE_DECORATOR) {
+            fptr->encs.ecflags |= ECONV_UNIVERSAL_NEWLINE_DECORATOR;
+        }
 #endif
     }
     else {
-	if (NEED_NEWLINE_DECORATOR_ON_READ(fptr)) {
-	    fptr->encs.ecflags |= ECONV_UNIVERSAL_NEWLINE_DECORATOR;
-	}
+        if (NEED_NEWLINE_DECORATOR_ON_READ(fptr)) {
+            fptr->encs.ecflags |= ECONV_UNIVERSAL_NEWLINE_DECORATOR;
+        }
 #ifdef TEXTMODE_NEWLINE_DECORATOR_ON_WRITE
-	if (NEED_NEWLINE_DECORATOR_ON_WRITE(fptr)) {
-	    fptr->encs.ecflags |= TEXTMODE_NEWLINE_DECORATOR_ON_WRITE;
-	}
+        if (NEED_NEWLINE_DECORATOR_ON_WRITE(fptr)) {
+            fptr->encs.ecflags |= TEXTMODE_NEWLINE_DECORATOR_ON_WRITE;
+        }
 #endif
     }
     fptr->pid = pid;
@@ -7369,7 +7717,7 @@ pipe_open(VALUE execarg_obj, const char *modestr, int fmode,
 #else
 static VALUE
 pipe_open(VALUE execarg_obj, const char *modestr, int fmode,
-	  const convconfig_t *convconfig)
+          const convconfig_t *convconfig)
 {
     rb_raise(rb_eNotImpError, "popen() is not available");
 }
@@ -7380,10 +7728,10 @@ is_popen_fork(VALUE prog)
 {
     if (RSTRING_LEN(prog) == 1 && RSTRING_PTR(prog)[0] == '-') {
 #if !defined(HAVE_WORKING_FORK)
-	rb_raise(rb_eNotImpError,
-		 "fork() function is unimplemented on this machine");
+        rb_raise(rb_eNotImpError,
+                 "fork() function is unimplemented on this machine");
 #else
-	return TRUE;
+        return TRUE;
 #endif
     }
     return FALSE;
@@ -7391,7 +7739,7 @@ is_popen_fork(VALUE prog)
 
 static VALUE
 pipe_open_s(VALUE prog, const char *modestr, int fmode,
-	    const convconfig_t *convconfig)
+            const convconfig_t *convconfig)
 {
     int argc = 1;
     VALUE *argv = &prog;
@@ -7407,7 +7755,7 @@ pipe_close(VALUE io)
 {
     rb_io_t *fptr = io_close_fptr(io);
     if (fptr) {
-	fptr_waitpid(fptr, rb_thread_to_be_killed(rb_thread_current()));
+        fptr_waitpid(fptr, rb_thread_to_be_killed(rb_thread_current()));
     }
     return Qnil;
 }
@@ -7435,7 +7783,7 @@ static VALUE popen_finish(VALUE port, VALUE klass);
  *  and the block's value is assigned to global variable <tt>$?</tt> and returned.
  *
  *  Optional argument +mode+ may be any valid \IO mode.
- *  See IO@Modes.
+ *  See {Access Modes}[rdoc-ref:File@Access+Modes].
  *
  *  Required argument +cmd+ determines which of the following occurs:
  *
@@ -7524,7 +7872,7 @@ static VALUE popen_finish(VALUE port, VALUE klass);
  *
  *  - <tt>cmd[0][0]</tt> (the first string in the nested array) is the name of a program that is run.
  *  - <tt>cmd[0][1]</tt> (the second string in the nested array) is set as the program's <tt>argv[0]</tt>.
- *  - <tt>cmd[1..-1] (the strings in the outer array) are the program's arguments.
+ *  - <tt>cmd[1..-1]</tt> (the strings in the outer array) are the program's arguments.
  *
  *  Example (sets <tt>$0</tt> to 'foo'):
  *
@@ -7581,15 +7929,15 @@ rb_io_s_popen(int argc, VALUE *argv, VALUE klass)
     if (argc > 1 && !NIL_P(env = rb_check_hash_type(argv[0]))) --argc, ++argv;
     switch (argc) {
       case 2:
-	pmode = argv[1];
+        pmode = argv[1];
       case 1:
-	pname = argv[0];
-	break;
+        pname = argv[0];
+        break;
       default:
-	{
-	    int ex = !NIL_P(opt);
-	    rb_error_arity(argc + ex, 1 + ex, 2 + ex);
-	}
+        {
+            int ex = !NIL_P(opt);
+            rb_error_arity(argc + ex, 1 + ex, 2 + ex);
+        }
     }
     return popen_finish(rb_io_popen(pname, pmode, env, opt), klass);
 }
@@ -7604,26 +7952,26 @@ rb_io_popen(VALUE pname, VALUE pmode, VALUE env, VALUE opt)
 
     tmp = rb_check_array_type(pname);
     if (!NIL_P(tmp)) {
-	long len = RARRAY_LEN(tmp);
+        long len = RARRAY_LEN(tmp);
 #if SIZEOF_LONG > SIZEOF_INT
-	if (len > INT_MAX) {
-	    rb_raise(rb_eArgError, "too many arguments");
-	}
+        if (len > INT_MAX) {
+            rb_raise(rb_eArgError, "too many arguments");
+        }
 #endif
         execarg_obj = rb_execarg_new((int)len, RARRAY_CONST_PTR(tmp), FALSE, FALSE);
-	RB_GC_GUARD(tmp);
+        RB_GC_GUARD(tmp);
     }
     else {
-	SafeStringValue(pname);
-	execarg_obj = Qnil;
-	if (!is_popen_fork(pname))
+        SafeStringValue(pname);
+        execarg_obj = Qnil;
+        if (!is_popen_fork(pname))
             execarg_obj = rb_execarg_new(1, &pname, TRUE, FALSE);
     }
     if (!NIL_P(execarg_obj)) {
-	if (!NIL_P(opt))
-	    opt = rb_execarg_extract_options(execarg_obj, opt);
-	if (!NIL_P(env))
-	    rb_execarg_setenv(execarg_obj, env);
+        if (!NIL_P(opt))
+            opt = rb_execarg_extract_options(execarg_obj, opt);
+        if (!NIL_P(env))
+            rb_execarg_setenv(execarg_obj, env);
     }
     rb_io_extract_modeenc(&pmode, 0, opt, &oflags, &fmode, &convconfig);
     modestr = rb_io_oflags_modestr(oflags);
@@ -7635,18 +7983,18 @@ static VALUE
 popen_finish(VALUE port, VALUE klass)
 {
     if (NIL_P(port)) {
-	/* child */
-	if (rb_block_given_p()) {
-	    rb_yield(Qnil);
+        /* child */
+        if (rb_block_given_p()) {
+            rb_protect(rb_yield, Qnil, NULL);
             rb_io_flush(rb_ractor_stdout());
             rb_io_flush(rb_ractor_stderr());
-	    _exit(0);
-	}
-	return Qnil;
+            _exit(0);
+        }
+        return Qnil;
     }
     RBASIC_SET_CLASS(port, klass);
     if (rb_block_given_p()) {
-	return rb_ensure(rb_yield, port, pipe_close, port);
+        return rb_ensure(rb_yield, port, pipe_close, port);
     }
     return port;
 }
@@ -7725,7 +8073,7 @@ rb_io_s_open(int argc, VALUE *argv, VALUE klass)
     VALUE io = rb_class_new_instance_kw(argc, argv, klass, RB_PASS_CALLED_KEYWORDS);
 
     if (rb_block_given_p()) {
-	return rb_ensure(rb_yield, io, io_close, io);
+        return rb_ensure(rb_yield, io, io_close, io);
     }
 
     return io;
@@ -7765,8 +8113,8 @@ rb_io_s_sysopen(int argc, VALUE *argv, VALUE _)
     else if (!NIL_P(intmode = rb_check_to_integer(vmode, "to_int")))
         oflags = NUM2INT(intmode);
     else {
-	SafeStringValue(vmode);
-	oflags = rb_io_modestr_oflags(StringValueCStr(vmode));
+        SafeStringValue(vmode);
+        oflags = rb_io_modestr_oflags(StringValueCStr(vmode));
     }
     if (NIL_P(vperm)) perm = 0666;
     else              perm = NUM2MODET(vperm);
@@ -7896,32 +8244,32 @@ rb_f_open(int argc, VALUE *argv, VALUE _)
     int redirect = FALSE;
 
     if (argc >= 1) {
-	CONST_ID(to_open, "to_open");
-	if (rb_respond_to(argv[0], to_open)) {
-	    redirect = TRUE;
-	}
-	else {
-	    VALUE tmp = argv[0];
-	    FilePathValue(tmp);
-	    if (NIL_P(tmp)) {
-		redirect = TRUE;
-	    }
-	    else {
+        CONST_ID(to_open, "to_open");
+        if (rb_respond_to(argv[0], to_open)) {
+            redirect = TRUE;
+        }
+        else {
+            VALUE tmp = argv[0];
+            FilePathValue(tmp);
+            if (NIL_P(tmp)) {
+                redirect = TRUE;
+            }
+            else {
                 VALUE cmd = check_pipe_command(tmp);
                 if (!NIL_P(cmd)) {
-		    argv[0] = cmd;
-		    return rb_io_s_popen(argc, argv, rb_cIO);
-		}
-	    }
-	}
+                    argv[0] = cmd;
+                    return rb_io_s_popen(argc, argv, rb_cIO);
+                }
+            }
+        }
     }
     if (redirect) {
         VALUE io = rb_funcallv_kw(argv[0], to_open, argc-1, argv+1, RB_PASS_CALLED_KEYWORDS);
 
-	if (rb_block_given_p()) {
-	    return rb_ensure(rb_yield, io, io_close, io);
-	}
-	return io;
+        if (rb_block_given_p()) {
+            return rb_ensure(rb_yield, io, io_close, io);
+        }
+        return io;
     }
     return rb_io_s_open(argc, argv, rb_cFile);
 }
@@ -7942,15 +8290,15 @@ rb_io_open(VALUE io, VALUE filename, VALUE vmode, VALUE vperm, VALUE opt)
 
 static VALUE
 rb_io_open_generic(VALUE klass, VALUE filename, int oflags, int fmode,
-		   const convconfig_t *convconfig, mode_t perm)
+                   const convconfig_t *convconfig, mode_t perm)
 {
     VALUE cmd;
     if (klass == rb_cIO && !NIL_P(cmd = check_pipe_command(filename))) {
-	return pipe_open_s(cmd, rb_io_oflags_modestr(oflags), fmode, convconfig);
+        return pipe_open_s(cmd, rb_io_oflags_modestr(oflags), fmode, convconfig);
     }
     else {
-	return rb_file_open_generic(io_alloc(klass), filename,
-				    oflags, fmode, convconfig, perm);
+        return rb_file_open_generic(io_alloc(klass), filename,
+                                    oflags, fmode, convconfig, perm);
     }
 }
 
@@ -7959,7 +8307,7 @@ io_reopen(VALUE io, VALUE nfile)
 {
     rb_io_t *fptr, *orig;
     int fd, fd2;
-    off_t pos = 0;
+    rb_off_t pos = 0;
 
     nfile = rb_io_get_io(nfile);
     GetOpenFile(io, fptr);
@@ -7970,11 +8318,11 @@ io_reopen(VALUE io, VALUE nfile)
         if ((fptr->stdio_file == stdin && !(orig->mode & FMODE_READABLE)) ||
             (fptr->stdio_file == stdout && !(orig->mode & FMODE_WRITABLE)) ||
             (fptr->stdio_file == stderr && !(orig->mode & FMODE_WRITABLE))) {
-	    rb_raise(rb_eArgError,
-		     "%s can't change access mode from \"%s\" to \"%s\"",
-		     PREP_STDIO_NAME(fptr), rb_io_fmode_modestr(fptr->mode),
-		     rb_io_fmode_modestr(orig->mode));
-	}
+            rb_raise(rb_eArgError,
+                     "%s can't change access mode from \"%s\" to \"%s\"",
+                     PREP_STDIO_NAME(fptr), rb_io_fmode_modestr(fptr->mode),
+                     rb_io_fmode_modestr(orig->mode));
+        }
     }
     if (fptr->mode & FMODE_WRITABLE) {
         if (io_fflush(fptr) < 0)
@@ -7984,7 +8332,7 @@ io_reopen(VALUE io, VALUE nfile)
         flush_before_seek(fptr);
     }
     if (orig->mode & FMODE_READABLE) {
-	pos = io_tell(orig);
+        pos = io_tell(orig);
     }
     if (orig->mode & FMODE_WRITABLE) {
         if (io_fflush(orig) < 0)
@@ -8002,13 +8350,13 @@ io_reopen(VALUE io, VALUE nfile)
     fd = fptr->fd;
     fd2 = orig->fd;
     if (fd != fd2) {
-	if (IS_PREP_STDIO(fptr) || fd <= 2 || !fptr->stdio_file) {
-	    /* need to keep FILE objects of stdin, stdout and stderr */
-	    if (rb_cloexec_dup2(fd2, fd) < 0)
-		rb_sys_fail_path(orig->pathv);
+        if (IS_PREP_STDIO(fptr) || fd <= 2 || !fptr->stdio_file) {
+            /* need to keep FILE objects of stdin, stdout and stderr */
+            if (rb_cloexec_dup2(fd2, fd) < 0)
+                rb_sys_fail_path(orig->pathv);
             rb_update_max_fd(fd);
-	}
-	else {
+        }
+        else {
             fclose(fptr->stdio_file);
             fptr->stdio_file = 0;
             fptr->fd = -1;
@@ -8016,20 +8364,20 @@ io_reopen(VALUE io, VALUE nfile)
                 rb_sys_fail_path(orig->pathv);
             rb_update_max_fd(fd);
             fptr->fd = fd;
-	}
-	rb_thread_fd_close(fd);
-	if ((orig->mode & FMODE_READABLE) && pos >= 0) {
-	    if (io_seek(fptr, pos, SEEK_SET) < 0 && errno) {
-		rb_sys_fail_path(fptr->pathv);
-	    }
-	    if (io_seek(orig, pos, SEEK_SET) < 0 && errno) {
-		rb_sys_fail_path(orig->pathv);
-	    }
-	}
+        }
+        rb_thread_fd_close(fd);
+        if ((orig->mode & FMODE_READABLE) && pos >= 0) {
+            if (io_seek(fptr, pos, SEEK_SET) < 0 && errno) {
+                rb_sys_fail_path(fptr->pathv);
+            }
+            if (io_seek(orig, pos, SEEK_SET) < 0 && errno) {
+                rb_sys_fail_path(orig->pathv);
+            }
+        }
     }
 
     if (fptr->mode & FMODE_BINMODE) {
-	rb_io_binmode(io);
+        rb_io_binmode(io);
     }
 
     RBASIC_SET_CLASS(io, rb_obj_class(nfile));
@@ -8043,8 +8391,8 @@ static int
 rb_freopen(VALUE fname, const char *mode, FILE *fp)
 {
     if (!freopen(RSTRING_PTR(fname), mode, fp)) {
-	RB_GC_GUARD(fname);
-	return errno;
+        RB_GC_GUARD(fname);
+        return errno;
     }
     return 0;
 }
@@ -8092,44 +8440,44 @@ rb_io_reopen(int argc, VALUE *argv, VALUE file)
     rb_io_t *fptr;
 
     if (rb_scan_args(argc, argv, "11:", &fname, &nmode, &opt) == 1) {
-	VALUE tmp = rb_io_check_io(fname);
-	if (!NIL_P(tmp)) {
-	    return io_reopen(file, tmp);
-	}
+        VALUE tmp = rb_io_check_io(fname);
+        if (!NIL_P(tmp)) {
+            return io_reopen(file, tmp);
+        }
     }
 
     FilePathValue(fname);
     rb_io_taint_check(file);
     fptr = RFILE(file)->fptr;
     if (!fptr) {
-	fptr = RFILE(file)->fptr = ZALLOC(rb_io_t);
+        fptr = RFILE(file)->fptr = ZALLOC(rb_io_t);
     }
 
     if (!NIL_P(nmode) || !NIL_P(opt)) {
-	int fmode;
-	convconfig_t convconfig;
+        int fmode;
+        convconfig_t convconfig;
 
-	rb_io_extract_modeenc(&nmode, 0, opt, &oflags, &fmode, &convconfig);
-	if (IS_PREP_STDIO(fptr) &&
+        rb_io_extract_modeenc(&nmode, 0, opt, &oflags, &fmode, &convconfig);
+        if (IS_PREP_STDIO(fptr) &&
             ((fptr->mode & FMODE_READWRITE) & (fmode & FMODE_READWRITE)) !=
             (fptr->mode & FMODE_READWRITE)) {
-	    rb_raise(rb_eArgError,
-		     "%s can't change access mode from \"%s\" to \"%s\"",
-		     PREP_STDIO_NAME(fptr), rb_io_fmode_modestr(fptr->mode),
-		     rb_io_fmode_modestr(fmode));
-	}
-	fptr->mode = fmode;
-	fptr->encs = convconfig;
+            rb_raise(rb_eArgError,
+                     "%s can't change access mode from \"%s\" to \"%s\"",
+                     PREP_STDIO_NAME(fptr), rb_io_fmode_modestr(fptr->mode),
+                     rb_io_fmode_modestr(fmode));
+        }
+        fptr->mode = fmode;
+        fptr->encs = convconfig;
     }
     else {
-	oflags = rb_io_fmode_oflags(fptr->mode);
+        oflags = rb_io_fmode_oflags(fptr->mode);
     }
 
     fptr->pathv = fname;
     if (fptr->fd < 0) {
         fptr->fd = rb_sysopen(fptr->pathv, oflags, 0666);
-	fptr->stdio_file = 0;
-	return file;
+        fptr->stdio_file = 0;
+        return file;
     }
 
     if (fptr->mode & FMODE_WRITABLE) {
@@ -8139,9 +8487,9 @@ rb_io_reopen(int argc, VALUE *argv, VALUE file)
     fptr->rbuf.off = fptr->rbuf.len = 0;
 
     if (fptr->stdio_file) {
-	int e = rb_freopen(rb_str_encode_ospath(fptr->pathv),
-			   rb_io_oflags_modestr(oflags),
-			   fptr->stdio_file);
+        int e = rb_freopen(rb_str_encode_ospath(fptr->pathv),
+                           rb_io_oflags_modestr(oflags),
+                           fptr->stdio_file);
         if (e) rb_syserr_fail_path(e, fptr->pathv);
         fptr->fd = fileno(fptr->stdio_file);
         rb_fd_fix_cloexec(fptr->fd);
@@ -8159,14 +8507,14 @@ rb_io_reopen(int argc, VALUE *argv, VALUE file)
         }
     }
     else {
-	int tmpfd = rb_sysopen(fptr->pathv, oflags, 0666);
-	int err = 0;
-	if (rb_cloexec_dup2(tmpfd, fptr->fd) < 0)
-	    err = errno;
-	(void)close(tmpfd);
-	if (err) {
-	    rb_syserr_fail_path(err, fptr->pathv);
-	}
+        int tmpfd = rb_sysopen(fptr->pathv, oflags, 0666);
+        int err = 0;
+        if (rb_cloexec_dup2(tmpfd, fptr->fd) < 0)
+            err = errno;
+        (void)close(tmpfd);
+        if (err) {
+            rb_syserr_fail_path(err, fptr->pathv);
+        }
     }
 
     return file;
@@ -8179,7 +8527,7 @@ rb_io_init_copy(VALUE dest, VALUE io)
     rb_io_t *fptr, *orig;
     int fd;
     VALUE write_io;
-    off_t pos;
+    rb_off_t pos;
 
     io = rb_io_get_io(io);
     if (!OBJ_INIT_COPY(dest, io)) return dest;
@@ -8193,6 +8541,7 @@ rb_io_init_copy(VALUE dest, VALUE io)
     fptr->encs = orig->encs;
     fptr->pid = orig->pid;
     fptr->lineno = orig->lineno;
+    fptr->timeout = orig->timeout;
     if (!NIL_P(orig->pathv)) fptr->pathv = orig->pathv;
     fptr_copy_finalizer(fptr, orig);
 
@@ -8202,7 +8551,7 @@ rb_io_init_copy(VALUE dest, VALUE io)
     if (0 <= pos)
         io_seek(fptr, pos, SEEK_SET);
     if (fptr->mode & FMODE_BINMODE) {
-	rb_io_binmode(dest);
+        rb_io_binmode(dest);
     }
 
     write_io = GetWriteIO(io);
@@ -8220,7 +8569,10 @@ rb_io_init_copy(VALUE dest, VALUE io)
  *    printf(format_string, *objects) -> nil
  *
  *  Formats and writes +objects+ to the stream.
- *  See Kernel#sprintf for formatting details.
+ *
+ *  For details on +format_string+, see
+ *  {Format Specifications}[rdoc-ref:format_specifications.rdoc].
+ *
  */
 
 VALUE
@@ -8232,14 +8584,17 @@ rb_io_printf(int argc, const VALUE *argv, VALUE out)
 
 /*
  *  call-seq:
- *    printf(string, *objects)               -> nil
- *    printf(io, string, *objects) -> nil
+ *    printf(format_string, *objects)               -> nil
+ *    printf(io, format_string, *objects) -> nil
  *
  *  Equivalent to:
  *
- *    io.write(sprintf(string, *objects))
+ *    io.write(sprintf(format_string, *objects))
  *
- *  With the single argument +string+, formats +objects+ into the string,
+ *  For details on +format_string+, see
+ *  {Format Specifications}[rdoc-ref:format_specifications.rdoc].
+ *
+ *  With the single argument +format_string+, formats +objects+ into the string,
  *  then writes the formatted string to $stdout:
  *
  *    printf('%4.4d %10s %2.2f', 24, 24, 24.0)
@@ -8248,7 +8603,7 @@ rb_io_printf(int argc, const VALUE *argv, VALUE out)
  *
  *    0024         24 24.00#
  *
- *  With arguments +io+ and +string, formats +objects+ into the string,
+ *  With arguments +io+ and +format_string+, formats +objects+ into the string,
  *  then writes the formatted string to +io+:
  *
  *    printf($stderr, '%4.4d %10s %2.2f', 24, 24, 24.0)
@@ -8268,12 +8623,12 @@ rb_f_printf(int argc, VALUE *argv, VALUE _)
 
     if (argc == 0) return Qnil;
     if (RB_TYPE_P(argv[0], T_STRING)) {
-	out = rb_ractor_stdout();
+        out = rb_ractor_stdout();
     }
     else {
-	out = argv[0];
-	argv++;
-	argc--;
+        out = argv[0];
+        argv++;
+        argc--;
     }
     rb_io_write(out, rb_f_sprintf(argc, argv));
 
@@ -8297,6 +8652,7 @@ deprecated_str_setter(VALUE val, ID id, VALUE *var)
  *  Writes the given objects to the stream; returns +nil+.
  *  Appends the output record separator <tt>$OUTPUT_RECORD_SEPARATOR</tt>
  *  (<tt>$\\</tt>), if it is not +nil+.
+ *  See {Line IO}[rdoc-ref:IO@Line+IO].
  *
  *  With argument +objects+ given, for each object:
  *
@@ -8353,21 +8709,21 @@ rb_io_print(int argc, const VALUE *argv, VALUE out)
 
     /* if no argument given, print `$_' */
     if (argc == 0) {
-	argc = 1;
-	line = rb_lastline_get();
-	argv = &line;
+        argc = 1;
+        line = rb_lastline_get();
+        argv = &line;
     }
     if (argc > 1 && !NIL_P(rb_output_fs)) {
         rb_category_warn(RB_WARN_CATEGORY_DEPRECATED, "$, is set to non-nil value");
     }
     for (i=0; i<argc; i++) {
-	if (!NIL_P(rb_output_fs) && i>0) {
-	    rb_io_write(out, rb_output_fs);
-	}
-	rb_io_write(out, argv[i]);
+        if (!NIL_P(rb_output_fs) && i>0) {
+            rb_io_write(out, rb_output_fs);
+        }
+        rb_io_write(out, argv[i]);
     }
     if (argc > 0 && !NIL_P(rb_output_rs)) {
-	rb_io_write(out, rb_output_rs);
+        rb_io_write(out, rb_output_rs);
     }
 
     return Qnil;
@@ -8434,6 +8790,7 @@ rb_f_print(int argc, const VALUE *argv, VALUE _)
  *    putc(object) -> object
  *
  *  Writes a character to the stream.
+ *  See {Character IO}[rdoc-ref:IO@Character+IO].
  *
  *  If +object+ is numeric, converts to integer if necessary,
  *  then writes the character whose code is the
@@ -8454,11 +8811,11 @@ rb_io_putc(VALUE io, VALUE ch)
 {
     VALUE str;
     if (RB_TYPE_P(ch, T_STRING)) {
-	str = rb_str_substr(ch, 0, 1);
+        str = rb_str_substr(ch, 0, 1);
     }
     else {
-	char c = NUM2CHR(ch);
-	str = rb_str_new(&c, 1);
+        char c = NUM2CHR(ch);
+        str = rb_str_new(&c, 1);
     }
     rb_io_write(io, str);
     return ch;
@@ -8488,7 +8845,7 @@ rb_f_putc(VALUE recv, VALUE ch)
 {
     VALUE r_stdout = rb_ractor_stdout();
     if (recv == r_stdout) {
-	return rb_io_putc(recv, ch);
+        return rb_io_putc(recv, ch);
     }
     return forward(r_stdout, rb_intern("putc"), 1, &ch);
 }
@@ -8504,7 +8861,7 @@ rb_str_end_with_asciichar(VALUE str, int c)
 
     if (len == 0) return 0;
     if ((n = rb_enc_mbminlen(enc)) == 1) {
-	return ptr[len - 1] == c;
+        return ptr[len - 1] == c;
     }
     return rb_enc_ascget(ptr + ((len - 1) / n) * n, ptr + len, &n, enc) == c;
 }
@@ -8516,15 +8873,15 @@ io_puts_ary(VALUE ary, VALUE out, int recur)
     long i;
 
     if (recur) {
-	tmp = rb_str_new2("[...]");
-	rb_io_puts(1, &tmp, out);
-	return Qtrue;
+        tmp = rb_str_new2("[...]");
+        rb_io_puts(1, &tmp, out);
+        return Qtrue;
     }
     ary = rb_check_array_type(ary);
     if (NIL_P(ary)) return Qfalse;
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	tmp = RARRAY_AREF(ary, i);
-	rb_io_puts(1, &tmp, out);
+        tmp = RARRAY_AREF(ary, i);
+        rb_io_puts(1, &tmp, out);
     }
     return Qtrue;
 }
@@ -8537,6 +8894,7 @@ io_puts_ary(VALUE ary, VALUE out, int recur)
  *  returns +nil+.\
  *  Writes a newline after each that does not already end with a newline sequence.
  *  If called without arguments, writes a newline.
+ *  See {Line IO}[rdoc-ref:IO@Line+IO].
  *
  *  Note that each added newline is the character <tt>"\n"<//tt>,
  *  not the output record separator (<tt>$\\</tt>).
@@ -8578,31 +8936,38 @@ io_puts_ary(VALUE ary, VALUE out, int recur)
 VALUE
 rb_io_puts(int argc, const VALUE *argv, VALUE out)
 {
-    int i, n;
     VALUE line, args[2];
 
     /* if no argument given, print newline. */
     if (argc == 0) {
-	rb_io_write(out, rb_default_rs);
-	return Qnil;
+        rb_io_write(out, rb_default_rs);
+        return Qnil;
     }
-    for (i=0; i<argc; i++) {
-	if (RB_TYPE_P(argv[i], T_STRING)) {
-	    line = argv[i];
-	    goto string;
-	}
-	if (rb_exec_recursive(io_puts_ary, argv[i], out)) {
-	    continue;
-	}
-	line = rb_obj_as_string(argv[i]);
-      string:
-	n = 0;
-	args[n++] = line;
-	if (RSTRING_LEN(line) == 0 ||
-            !rb_str_end_with_asciichar(line, '\n')) {
-	    args[n++] = rb_default_rs;
-	}
-	rb_io_writev(out, n, args);
+    for (int i = 0; i < argc; i++) {
+        // Convert the argument to a string:
+        if (RB_TYPE_P(argv[i], T_STRING)) {
+            line = argv[i];
+        }
+        else if (rb_exec_recursive(io_puts_ary, argv[i], out)) {
+            continue;
+        }
+        else {
+            line = rb_obj_as_string(argv[i]);
+        }
+
+        // Write the line:
+        int n = 0;
+        if (RSTRING_LEN(line) == 0) {
+            args[n++] = rb_default_rs;
+        }
+        else {
+            args[n++] = line;
+            if (!rb_str_end_with_asciichar(line, '\n')) {
+                args[n++] = rb_default_rs;
+            }
+        }
+
+        rb_io_writev(out, n, args);
     }
 
     return Qnil;
@@ -8622,7 +8987,7 @@ rb_f_puts(int argc, VALUE *argv, VALUE recv)
 {
     VALUE r_stdout = rb_ractor_stdout();
     if (recv == r_stdout) {
-	return rb_io_puts(argc, argv, recv);
+        return rb_io_puts(argc, argv, recv);
     }
     return forward(r_stdout, rb_intern("puts"), argc, argv);
 }
@@ -8636,10 +9001,10 @@ rb_p_write(VALUE str)
     VALUE r_stdout = rb_ractor_stdout();
     if (RB_TYPE_P(r_stdout, T_FILE) &&
         rb_method_basic_definition_p(CLASS_OF(r_stdout), id_write)) {
-	io_writev(2, args, r_stdout);
+        io_writev(2, args, r_stdout);
     }
     else {
-	rb_io_writev(r_stdout, 2, args);
+        rb_io_writev(r_stdout, 2, args);
     }
     return Qnil;
 }
@@ -8656,14 +9021,14 @@ rb_p_result(int argc, const VALUE *argv)
     VALUE ret = Qnil;
 
     if (argc == 1) {
-	ret = argv[0];
+        ret = argv[0];
     }
     else if (argc > 1) {
-	ret = rb_ary_new4(argc, argv);
+        ret = rb_ary_new4(argc, argv);
     }
     VALUE r_stdout = rb_ractor_stdout();
     if (RB_TYPE_P(r_stdout, T_FILE)) {
-	rb_io_flush(r_stdout);
+        rb_uninterruptible(rb_io_flush, r_stdout);
     }
     return ret;
 }
@@ -8747,17 +9112,17 @@ rb_write_error2(const char *mesg, long len)
     VALUE out = rb_ractor_stderr();
     if (rb_stderr_to_original_p(out)) {
 #ifdef _WIN32
-	if (isatty(fileno(stderr))) {
-	    if (rb_w32_write_console(rb_str_new(mesg, len), fileno(stderr)) > 0) return;
-	}
+        if (isatty(fileno(stderr))) {
+            if (rb_w32_write_console(rb_str_new(mesg, len), fileno(stderr)) > 0) return;
+        }
 #endif
-	if (fwrite(mesg, sizeof(char), (size_t)len, stderr) < (size_t)len) {
-	    /* failed to write to stderr, what can we do? */
-	    return;
-	}
+        if (fwrite(mesg, sizeof(char), (size_t)len, stderr) < (size_t)len) {
+            /* failed to write to stderr, what can we do? */
+            return;
+        }
     }
     else {
-	rb_io_write(out, rb_str_new(mesg, len));
+        rb_io_write(out, rb_str_new(mesg, len));
     }
 }
 
@@ -8773,20 +9138,20 @@ rb_write_error_str(VALUE mesg)
     VALUE out = rb_ractor_stderr();
     /* a stopgap measure for the time being */
     if (rb_stderr_to_original_p(out)) {
-	size_t len = (size_t)RSTRING_LEN(mesg);
+        size_t len = (size_t)RSTRING_LEN(mesg);
 #ifdef _WIN32
-	if (isatty(fileno(stderr))) {
-	    if (rb_w32_write_console(mesg, fileno(stderr)) > 0) return;
-	}
+        if (isatty(fileno(stderr))) {
+            if (rb_w32_write_console(mesg, fileno(stderr)) > 0) return;
+        }
 #endif
-	if (fwrite(RSTRING_PTR(mesg), sizeof(char), len, stderr) < len) {
-	    RB_GC_GUARD(mesg);
-	    return;
-	}
+        if (fwrite(RSTRING_PTR(mesg), sizeof(char), len, stderr) < len) {
+            RB_GC_GUARD(mesg);
+            return;
+        }
     }
     else {
-	/* may unlock GVL, and  */
-	rb_io_write(out, mesg);
+        /* may unlock GVL, and  */
+        rb_io_write(out, mesg);
     }
 }
 
@@ -8794,7 +9159,7 @@ int
 rb_stderr_tty_p(void)
 {
     if (rb_stderr_to_original_p(rb_ractor_stderr()))
-	return isatty(fileno(stderr));
+        return isatty(fileno(stderr));
     return 0;
 }
 
@@ -8802,9 +9167,9 @@ static void
 must_respond_to(ID mid, VALUE val, ID id)
 {
     if (!rb_respond_to(val, mid)) {
-	rb_raise(rb_eTypeError, "%"PRIsVALUE" must have %"PRIsVALUE" method, %"PRIsVALUE" given",
-		 rb_id2str(id), rb_id2str(mid),
-		 rb_obj_class(val));
+        rb_raise(rb_eTypeError, "%"PRIsVALUE" must have %"PRIsVALUE" method, %"PRIsVALUE" given",
+                 rb_id2str(id), rb_id2str(mid),
+                 rb_obj_class(val));
     }
 }
 
@@ -8856,10 +9221,11 @@ prep_io(int fd, int fmode, VALUE klass, const char *path)
     fp->self = io;
     fp->fd = fd;
     fp->mode = fmode;
+    fp->timeout = Qnil;
     if (!io_check_tty(fp)) {
 #ifdef __CYGWIN__
-	fp->mode |= FMODE_BINMODE;
-	setmode(fd, O_BINARY);
+        fp->mode |= FMODE_BINMODE;
+        setmode(fd, O_BINARY);
 #endif
     }
     if (path) fp->pathv = rb_obj_freeze(rb_str_new_cstr(path));
@@ -8888,7 +9254,7 @@ prep_stdio(FILE *f, int fmode, VALUE klass, const char *path)
 #ifdef TEXTMODE_NEWLINE_DECORATOR_ON_WRITE
     fptr->encs.ecflags |= TEXTMODE_NEWLINE_DECORATOR_ON_WRITE;
     if (fmode & FMODE_READABLE) {
-	fptr->encs.ecflags |= ECONV_UNIVERSAL_NEWLINE_DECORATOR;
+        fptr->encs.ecflags |= ECONV_UNIVERSAL_NEWLINE_DECORATOR;
     }
 #endif
     fptr->stdio_file = f;
@@ -8959,7 +9325,8 @@ rb_io_fptr_new(void)
     fp->encs.enc2 = NULL;
     fp->encs.ecflags = 0;
     fp->encs.ecopts = Qnil;
-    fp->write_lock = 0;
+    fp->write_lock = Qnil;
+    fp->timeout = Qnil;
     return fp;
 }
 
@@ -9003,8 +9370,8 @@ rb_io_make_open_file(VALUE obj)
  *    io = IO.new(fd)
  *    io.external_encoding # => #<Encoding:UTF-8> # Not ASCII-8BIT.
  *
- *  Optional argument +mode+ (defaults to 'r') must specify a valid mode
- *  see IO@Modes:
+ *  Optional argument +mode+ (defaults to 'r') must specify a valid mode;
+ *  see {Access Modes}[rdoc-ref:File@Access+Modes]:
  *
  *    IO.new(fd, 'w')         # => #<IO:fd 3>
  *    IO.new(fd, File::WRONLY) # => #<IO:fd 3>
@@ -9041,7 +9408,7 @@ rb_io_initialize(int argc, VALUE *argv, VALUE io)
 
     fd = NUM2INT(fnum);
     if (rb_reserved_fd_p(fd)) {
-	rb_raise(rb_eArgError, "The given fd is not accessible because RubyVM reserves it");
+        rb_raise(rb_eArgError, "The given fd is not accessible because RubyVM reserves it");
     }
 #if defined(HAVE_FCNTL) && defined(F_GETFL)
     oflags = fcntl(fd, F_GETFL);
@@ -9053,29 +9420,42 @@ rb_io_initialize(int argc, VALUE *argv, VALUE io)
 #if defined(HAVE_FCNTL) && defined(F_GETFL)
     ofmode = rb_io_oflags_fmode(oflags);
     if (NIL_P(vmode)) {
-	fmode = ofmode;
+        fmode = ofmode;
     }
     else if ((~ofmode & fmode) & FMODE_READWRITE) {
-	VALUE error = INT2FIX(EINVAL);
-	rb_exc_raise(rb_class_new_instance(1, &error, rb_eSystemCallError));
+        VALUE error = INT2FIX(EINVAL);
+        rb_exc_raise(rb_class_new_instance(1, &error, rb_eSystemCallError));
     }
 #endif
-    if (!NIL_P(opt) && rb_hash_aref(opt, sym_autoclose) == Qfalse) {
-	fmode |= FMODE_PREP;
+    VALUE path = Qnil;
+
+    if (!NIL_P(opt)) {
+        if (rb_hash_aref(opt, sym_autoclose) == Qfalse) {
+            fmode |= FMODE_PREP;
+        }
+
+        path = rb_hash_aref(opt, RB_ID2SYM(idPath));
+        if (!NIL_P(path)) {
+            StringValue(path);
+            path = rb_str_new_frozen(path);
+        }
     }
+
     MakeOpenFile(io, fp);
     fp->self = io;
     fp->fd = fd;
     fp->mode = fmode;
     fp->encs = convconfig;
+    fp->pathv = path;
+    fp->timeout = Qnil;
     clear_codeconv(fp);
     io_check_tty(fp);
     if (fileno(stdin) == fd)
-	fp->stdio_file = stdin;
+        fp->stdio_file = stdin;
     else if (fileno(stdout) == fd)
-	fp->stdio_file = stdout;
+        fp->stdio_file = stdout;
     else if (fileno(stderr) == fd)
-	fp->stdio_file = stderr;
+        fp->stdio_file = stderr;
 
     if (fmode & FMODE_SETENC_BY_BOM) io_set_encoding_by_bom(io);
     return io;
@@ -9138,46 +9518,47 @@ rb_io_set_encoding_by_bom(VALUE io)
  *
  *  Argument +path+ must be a valid file path:
  *
- *    File.new('/etc/fstab')
- *    File.new('t.txt')
+ *    f = File.new('/etc/fstab')
+ *    f.close
+ *    f = File.new('t.txt')
+ *    f.close
  *
- *  Optional argument +mode+ (defaults to 'r') must specify a valid mode
- *  see IO@Modes:
+ *  Optional argument +mode+ (defaults to 'r') must specify a valid mode;
+ *  see {Access Modes}[rdoc-ref:File@Access+Modes]:
  *
- *    File.new('t.tmp', 'w')
- *    File.new('t.tmp', File::RDONLY)
+ *    f = File.new('t.tmp', 'w')
+ *    f.close
+ *    f = File.new('t.tmp', File::RDONLY)
+ *    f.close
  *
  *  Optional argument +perm+ (defaults to 0666) must specify valid permissions
- *  see {File Permissions}[rdoc-ref:IO@File+Permissions]:
+ *  see {File Permissions}[rdoc-ref:File@File+Permissions]:
  *
- *    File.new('t.tmp', File::CREAT, 0644)
- *    File.new('t.tmp', File::CREAT, 0444)
+ *    f = File.new('t.tmp', File::CREAT, 0644)
+ *    f.close
+ *    f = File.new('t.tmp', File::CREAT, 0444)
+ *    f.close
  *
  *  Optional keyword arguments +opts+ specify:
  *
  *  - {Open Options}[rdoc-ref:IO@Open+Options].
  *  - {Encoding options}[rdoc-ref:encodings.rdoc@Encoding+Options].
  *
- *  Examples:
- *
- *    File.new('t.tmp', autoclose: true)
- *    File.new('t.tmp', internal_encoding: nil)
- *
  */
 
 static VALUE
 rb_file_initialize(int argc, VALUE *argv, VALUE io)
 {
     if (RFILE(io)->fptr) {
-	rb_raise(rb_eRuntimeError, "reinitializing File");
+        rb_raise(rb_eRuntimeError, "reinitializing File");
     }
     if (0 < argc && argc < 3) {
-	VALUE fd = rb_check_to_int(argv[0]);
+        VALUE fd = rb_check_to_int(argv[0]);
 
-	if (!NIL_P(fd)) {
-	    argv[0] = fd;
-	    return rb_io_initialize(argc, argv, io);
-	}
+        if (!NIL_P(fd)) {
+            argv[0] = fd;
+            return rb_io_initialize(argc, argv, io);
+        }
     }
     rb_open_file(argc, argv, io);
 
@@ -9189,10 +9570,10 @@ static VALUE
 rb_io_s_new(int argc, VALUE *argv, VALUE klass)
 {
     if (rb_block_given_p()) {
-	VALUE cname = rb_obj_as_string(klass);
+        VALUE cname = rb_obj_as_string(klass);
 
-	rb_warn("%"PRIsVALUE"::new() does not take block; use %"PRIsVALUE"::open() instead",
-		cname, cname);
+        rb_warn("%"PRIsVALUE"::new() does not take block; use %"PRIsVALUE"::open() instead",
+                cname, cname);
     }
     return rb_class_new_instance_kw(argc, argv, klass, RB_PASS_CALLED_KEYWORDS);
 }
@@ -9253,12 +9634,223 @@ rb_io_set_autoclose(VALUE io, VALUE autoclose)
     rb_io_t *fptr;
     GetOpenFile(io, fptr);
     if (!RTEST(autoclose))
-	fptr->mode |= FMODE_PREP;
+        fptr->mode |= FMODE_PREP;
     else
-	fptr->mode &= ~FMODE_PREP;
+        fptr->mode &= ~FMODE_PREP;
     return autoclose;
 }
 
+static VALUE
+io_wait_event(VALUE io, int event, VALUE timeout, int return_io)
+{
+    VALUE result = rb_io_wait(io, RB_INT2NUM(event), timeout);
+
+    if (!RB_TEST(result)) {
+        return Qnil;
+    }
+
+    int mask = RB_NUM2INT(result);
+
+    if (mask & event) {
+        if (return_io)
+            return io;
+        else
+            return result;
+    }
+    else {
+        return Qfalse;
+    }
+}
+
+/*
+ * call-seq:
+ *   io.wait_readable          -> truthy or falsy
+ *   io.wait_readable(timeout) -> truthy or falsy
+ *
+ * Waits until IO is readable and returns a truthy value, or a falsy
+ * value when times out.  Returns a truthy value immediately when
+ * buffered data is available.
+ */
+
+static VALUE
+io_wait_readable(int argc, VALUE *argv, VALUE io)
+{
+    rb_io_t *fptr;
+
+    RB_IO_POINTER(io, fptr);
+    rb_io_check_readable(fptr);
+
+    if (rb_io_read_pending(fptr)) return Qtrue;
+
+    rb_check_arity(argc, 0, 1);
+    VALUE timeout = (argc == 1 ? argv[0] : Qnil);
+
+    return io_wait_event(io, RUBY_IO_READABLE, timeout, 1);
+}
+
+/*
+ * call-seq:
+ *   io.wait_writable          -> truthy or falsy
+ *   io.wait_writable(timeout) -> truthy or falsy
+ *
+ * Waits until IO is writable and returns a truthy value or a falsy
+ * value when times out.
+ */
+static VALUE
+io_wait_writable(int argc, VALUE *argv, VALUE io)
+{
+    rb_io_t *fptr;
+
+    RB_IO_POINTER(io, fptr);
+    rb_io_check_writable(fptr);
+
+    rb_check_arity(argc, 0, 1);
+    VALUE timeout = (argc == 1 ? argv[0] : Qnil);
+
+    return io_wait_event(io, RUBY_IO_WRITABLE, timeout, 1);
+}
+
+/*
+ * call-seq:
+ *   io.wait_priority          -> truthy or falsy
+ *   io.wait_priority(timeout) -> truthy or falsy
+ *
+ * Waits until IO is priority and returns a truthy value or a falsy
+ * value when times out. Priority data is sent and received using
+ * the Socket::MSG_OOB flag and is typically limited to streams.
+ */
+static VALUE
+io_wait_priority(int argc, VALUE *argv, VALUE io)
+{
+    rb_io_t *fptr = NULL;
+
+    RB_IO_POINTER(io, fptr);
+    rb_io_check_readable(fptr);
+
+    if (rb_io_read_pending(fptr)) return Qtrue;
+
+    rb_check_arity(argc, 0, 1);
+    VALUE timeout = argc == 1 ? argv[0] : Qnil;
+
+    return io_wait_event(io, RUBY_IO_PRIORITY, timeout, 1);
+}
+
+static int
+wait_mode_sym(VALUE mode)
+{
+    if (mode == ID2SYM(rb_intern("r"))) {
+        return RB_WAITFD_IN;
+    }
+    if (mode == ID2SYM(rb_intern("read"))) {
+        return RB_WAITFD_IN;
+    }
+    if (mode == ID2SYM(rb_intern("readable"))) {
+        return RB_WAITFD_IN;
+    }
+    if (mode == ID2SYM(rb_intern("w"))) {
+        return RB_WAITFD_OUT;
+    }
+    if (mode == ID2SYM(rb_intern("write"))) {
+        return RB_WAITFD_OUT;
+    }
+    if (mode == ID2SYM(rb_intern("writable"))) {
+        return RB_WAITFD_OUT;
+    }
+    if (mode == ID2SYM(rb_intern("rw"))) {
+        return RB_WAITFD_IN|RB_WAITFD_OUT;
+    }
+    if (mode == ID2SYM(rb_intern("read_write"))) {
+        return RB_WAITFD_IN|RB_WAITFD_OUT;
+    }
+    if (mode == ID2SYM(rb_intern("readable_writable"))) {
+        return RB_WAITFD_IN|RB_WAITFD_OUT;
+    }
+
+    rb_raise(rb_eArgError, "unsupported mode: %"PRIsVALUE, mode);
+}
+
+static inline rb_io_event_t
+io_event_from_value(VALUE value)
+{
+    int events = RB_NUM2INT(value);
+
+    if (events <= 0) rb_raise(rb_eArgError, "Events must be positive integer!");
+
+    return events;
+}
+
+/*
+ * call-seq:
+ *   io.wait(events, timeout) -> event mask, false or nil
+ *   io.wait(timeout = nil, mode = :read) -> self, true, or false
+ *
+ * Waits until the IO becomes ready for the specified events and returns the
+ * subset of events that become ready, or a falsy value when times out.
+ *
+ * The events can be a bit mask of +IO::READABLE+, +IO::WRITABLE+ or
+ * +IO::PRIORITY+.
+ *
+ * Returns an event mask (truthy value) immediately when buffered data is available.
+ *
+ * Optional parameter +mode+ is one of +:read+, +:write+, or
+ * +:read_write+.
+ */
+
+static VALUE
+io_wait(int argc, VALUE *argv, VALUE io)
+{
+    VALUE timeout = Qundef;
+    rb_io_event_t events = 0;
+    int return_io = 0;
+
+    // The documented signature for this method is actually incorrect.
+    // A single timeout is allowed in any position, and multiple symbols can be given.
+    // Whether this is intentional or not, I don't know, and as such I consider this to
+    // be a legacy/slow path.
+    if (argc != 2 || (RB_SYMBOL_P(argv[0]) || RB_SYMBOL_P(argv[1]))) {
+        // We'd prefer to return the actual mask, but this form would return the io itself:
+        return_io = 1;
+
+        // Slow/messy path:
+        for (int i = 0; i < argc; i += 1) {
+            if (RB_SYMBOL_P(argv[i])) {
+                events |= wait_mode_sym(argv[i]);
+            }
+            else if (UNDEF_P(timeout)) {
+                rb_time_interval(timeout = argv[i]);
+            }
+            else {
+                rb_raise(rb_eArgError, "timeout given more than once");
+            }
+        }
+
+        if (UNDEF_P(timeout)) timeout = Qnil;
+
+        if (events == 0) {
+            events = RUBY_IO_READABLE;
+        }
+    }
+    else /* argc == 2 and neither are symbols */ {
+        // This is the fast path:
+        events = io_event_from_value(argv[0]);
+        timeout = argv[1];
+    }
+
+    if (events & RUBY_IO_READABLE) {
+        rb_io_t *fptr = NULL;
+        RB_IO_POINTER(io, fptr);
+
+        if (rb_io_read_pending(fptr)) {
+            // This was the original behaviour:
+            if (return_io) return Qtrue;
+            // New behaviour always returns an event mask:
+            else return RB_INT2NUM(RUBY_IO_READABLE);
+        }
+    }
+
+    return io_wait_event(io, events, timeout, return_io);
+}
+
 static void
 argf_mark(void *ptr)
 {
@@ -9329,11 +9921,11 @@ argf_initialize_copy(VALUE argf, VALUE orig)
  *  call-seq:
  *     ARGF.lineno = integer  -> integer
  *
- *  Sets the line number of +ARGF+ as a whole to the given +Integer+.
+ *  Sets the line number of ARGF as a whole to the given Integer.
  *
- *  +ARGF+ sets the line number automatically as you read data, so normally
+ *  ARGF sets the line number automatically as you read data, so normally
  *  you will not need to set it explicitly. To access the current line number
- *  use +ARGF.lineno+.
+ *  use ARGF.lineno.
  *
  *  For example:
  *
@@ -9348,7 +9940,7 @@ argf_set_lineno(VALUE argf, VALUE val)
 {
     ARGF.lineno = NUM2INT(val);
     ARGF.last_lineno = ARGF.lineno;
-    return Qnil;
+    return val;
 }
 
 /*
@@ -9356,7 +9948,7 @@ argf_set_lineno(VALUE argf, VALUE val)
  *     ARGF.lineno  -> integer
  *
  *  Returns the current line number of ARGF as a whole. This value
- *  can be set manually with +ARGF.lineno=+.
+ *  can be set manually with ARGF.lineno=.
  *
  *  For example:
  *
@@ -9381,7 +9973,7 @@ argf_forward(int argc, VALUE *argv, VALUE argf)
     (ARGF.current_file == rb_stdin && !RB_TYPE_P(ARGF.current_file, T_FILE))
 #define ARGF_FORWARD(argc, argv) do {\
     if (ARGF_GENERIC_INPUT_P())\
-	return argf_forward((argc), (argv), argf);\
+        return argf_forward((argc), (argv), argf);\
 } while (0)
 #define NEXT_ARGF_FORWARD(argc, argv) do {\
     if (!next_argv()) return Qnil;\
@@ -9394,7 +9986,7 @@ argf_close(VALUE argf)
     VALUE file = ARGF.current_file;
     if (file == rb_stdin) return;
     if (RB_TYPE_P(file, T_FILE)) {
-	rb_io_set_write_io(file, Qnil);
+        rb_io_set_write_io(file, Qnil);
     }
     io_close(file);
     ARGF.init_p = -1;
@@ -9417,163 +10009,163 @@ argf_next_argv(VALUE argf)
     }
 
     if (ARGF.init_p == 0) {
-	if (!NIL_P(ARGF.argv) && RARRAY_LEN(ARGF.argv) > 0) {
-	    ARGF.next_p = 1;
-	}
-	else {
-	    ARGF.next_p = -1;
-	}
-	ARGF.init_p = 1;
+        if (!NIL_P(ARGF.argv) && RARRAY_LEN(ARGF.argv) > 0) {
+            ARGF.next_p = 1;
+        }
+        else {
+            ARGF.next_p = -1;
+        }
+        ARGF.init_p = 1;
     }
     else {
-	if (NIL_P(ARGF.argv)) {
-	    ARGF.next_p = -1;
-	}
-	else if (ARGF.next_p == -1 && RARRAY_LEN(ARGF.argv) > 0) {
-	    ARGF.next_p = 1;
-	}
+        if (NIL_P(ARGF.argv)) {
+            ARGF.next_p = -1;
+        }
+        else if (ARGF.next_p == -1 && RARRAY_LEN(ARGF.argv) > 0) {
+            ARGF.next_p = 1;
+        }
     }
 
     if (ARGF.next_p == 1) {
-	if (ARGF.init_p == 1) argf_close(argf);
+        if (ARGF.init_p == 1) argf_close(argf);
       retry:
-	if (RARRAY_LEN(ARGF.argv) > 0) {
-	    VALUE filename = rb_ary_shift(ARGF.argv);
-	    FilePathValue(filename);
-	    ARGF.filename = filename;
-	    filename = rb_str_encode_ospath(filename);
-	    fn = StringValueCStr(filename);
-	    if (RSTRING_LEN(filename) == 1 && fn[0] == '-') {
-		ARGF.current_file = rb_stdin;
-		if (ARGF.inplace) {
-		    rb_warn("Can't do inplace edit for stdio; skipping");
-		    goto retry;
-		}
-	    }
-	    else {
-		VALUE write_io = Qnil;
-		int fr = rb_sysopen(filename, O_RDONLY, 0);
-
-		if (ARGF.inplace) {
-		    struct stat st;
+        if (RARRAY_LEN(ARGF.argv) > 0) {
+            VALUE filename = rb_ary_shift(ARGF.argv);
+            FilePathValue(filename);
+            ARGF.filename = filename;
+            filename = rb_str_encode_ospath(filename);
+            fn = StringValueCStr(filename);
+            if (RSTRING_LEN(filename) == 1 && fn[0] == '-') {
+                ARGF.current_file = rb_stdin;
+                if (ARGF.inplace) {
+                    rb_warn("Can't do inplace edit for stdio; skipping");
+                    goto retry;
+                }
+            }
+            else {
+                VALUE write_io = Qnil;
+                int fr = rb_sysopen(filename, O_RDONLY, 0);
+
+                if (ARGF.inplace) {
+                    struct stat st;
 #ifndef NO_SAFE_RENAME
-		    struct stat st2;
-#endif
-		    VALUE str;
-		    int fw;
-
-		    if (RB_TYPE_P(r_stdout, T_FILE) && r_stdout != orig_stdout) {
-			rb_io_close(r_stdout);
-		    }
-		    fstat(fr, &st);
-		    str = filename;
-		    if (!NIL_P(ARGF.inplace)) {
-			VALUE suffix = ARGF.inplace;
-			str = rb_str_dup(str);
-			if (NIL_P(rb_str_cat_conv_enc_opts(str, RSTRING_LEN(str),
-							   RSTRING_PTR(suffix), RSTRING_LEN(suffix),
-							   rb_enc_get(suffix), 0, Qnil))) {
-			    rb_str_append(str, suffix);
-			}
+                    struct stat st2;
+#endif
+                    VALUE str;
+                    int fw;
+
+                    if (RB_TYPE_P(r_stdout, T_FILE) && r_stdout != orig_stdout) {
+                        rb_io_close(r_stdout);
+                    }
+                    fstat(fr, &st);
+                    str = filename;
+                    if (!NIL_P(ARGF.inplace)) {
+                        VALUE suffix = ARGF.inplace;
+                        str = rb_str_dup(str);
+                        if (NIL_P(rb_str_cat_conv_enc_opts(str, RSTRING_LEN(str),
+                                                           RSTRING_PTR(suffix), RSTRING_LEN(suffix),
+                                                           rb_enc_get(suffix), 0, Qnil))) {
+                            rb_str_append(str, suffix);
+                        }
 #ifdef NO_SAFE_RENAME
-			(void)close(fr);
-			(void)unlink(RSTRING_PTR(str));
-			if (rename(fn, RSTRING_PTR(str)) < 0) {
-			    rb_warn("Can't rename %"PRIsVALUE" to %"PRIsVALUE": %s, skipping file",
-				    filename, str, strerror(errno));
-			    goto retry;
-			}
-			fr = rb_sysopen(str, O_RDONLY, 0);
+                        (void)close(fr);
+                        (void)unlink(RSTRING_PTR(str));
+                        if (rename(fn, RSTRING_PTR(str)) < 0) {
+                            rb_warn("Can't rename %"PRIsVALUE" to %"PRIsVALUE": %s, skipping file",
+                                    filename, str, strerror(errno));
+                            goto retry;
+                        }
+                        fr = rb_sysopen(str, O_RDONLY, 0);
 #else
-			if (rename(fn, RSTRING_PTR(str)) < 0) {
-			    rb_warn("Can't rename %"PRIsVALUE" to %"PRIsVALUE": %s, skipping file",
-				    filename, str, strerror(errno));
-			    close(fr);
-			    goto retry;
-			}
-#endif
-		    }
-		    else {
+                        if (rename(fn, RSTRING_PTR(str)) < 0) {
+                            rb_warn("Can't rename %"PRIsVALUE" to %"PRIsVALUE": %s, skipping file",
+                                    filename, str, strerror(errno));
+                            close(fr);
+                            goto retry;
+                        }
+#endif
+                    }
+                    else {
 #ifdef NO_SAFE_RENAME
-			rb_fatal("Can't do inplace edit without backup");
+                        rb_fatal("Can't do inplace edit without backup");
 #else
-			if (unlink(fn) < 0) {
-			    rb_warn("Can't remove %"PRIsVALUE": %s, skipping file",
-				    filename, strerror(errno));
-			    close(fr);
-			    goto retry;
-			}
-#endif
-		    }
-		    fw = rb_sysopen(filename, O_WRONLY|O_CREAT|O_TRUNC, 0666);
+                        if (unlink(fn) < 0) {
+                            rb_warn("Can't remove %"PRIsVALUE": %s, skipping file",
+                                    filename, strerror(errno));
+                            close(fr);
+                            goto retry;
+                        }
+#endif
+                    }
+                    fw = rb_sysopen(filename, O_WRONLY|O_CREAT|O_TRUNC, 0666);
 #ifndef NO_SAFE_RENAME
-		    fstat(fw, &st2);
+                    fstat(fw, &st2);
 #ifdef HAVE_FCHMOD
-		    fchmod(fw, st.st_mode);
+                    fchmod(fw, st.st_mode);
 #else
-		    chmod(fn, st.st_mode);
+                    chmod(fn, st.st_mode);
 #endif
-		    if (st.st_uid!=st2.st_uid || st.st_gid!=st2.st_gid) {
-			int err;
+                    if (st.st_uid!=st2.st_uid || st.st_gid!=st2.st_gid) {
+                        int err;
 #ifdef HAVE_FCHOWN
-			err = fchown(fw, st.st_uid, st.st_gid);
+                        err = fchown(fw, st.st_uid, st.st_gid);
 #else
-			err = chown(fn, st.st_uid, st.st_gid);
-#endif
-			if (err && getuid() == 0 && st2.st_uid == 0) {
-			    const char *wkfn = RSTRING_PTR(filename);
-			    rb_warn("Can't set owner/group of %"PRIsVALUE" to same as %"PRIsVALUE": %s, skipping file",
-				    filename, str, strerror(errno));
-			    (void)close(fr);
-			    (void)close(fw);
-			    (void)unlink(wkfn);
-			    goto retry;
-			}
-		    }
-#endif
-		    write_io = prep_io(fw, FMODE_WRITABLE, rb_cFile, fn);
-		    rb_ractor_stdout_set(write_io);
-		    if (stdout_binmode) rb_io_binmode(rb_stdout);
-		}
-		fmode = FMODE_READABLE;
-		if (!ARGF.binmode) {
-		    fmode |= DEFAULT_TEXTMODE;
-		}
-		ARGF.current_file = prep_io(fr, fmode, rb_cFile, fn);
-		if (!NIL_P(write_io)) {
-		    rb_io_set_write_io(ARGF.current_file, write_io);
-		}
-		RB_GC_GUARD(filename);
-	    }
-	    if (ARGF.binmode) rb_io_ascii8bit_binmode(ARGF.current_file);
-	    GetOpenFile(ARGF.current_file, fptr);
-	    if (ARGF.encs.enc) {
-		fptr->encs = ARGF.encs;
+                        err = chown(fn, st.st_uid, st.st_gid);
+#endif
+                        if (err && getuid() == 0 && st2.st_uid == 0) {
+                            const char *wkfn = RSTRING_PTR(filename);
+                            rb_warn("Can't set owner/group of %"PRIsVALUE" to same as %"PRIsVALUE": %s, skipping file",
+                                    filename, str, strerror(errno));
+                            (void)close(fr);
+                            (void)close(fw);
+                            (void)unlink(wkfn);
+                            goto retry;
+                        }
+                    }
+#endif
+                    write_io = prep_io(fw, FMODE_WRITABLE, rb_cFile, fn);
+                    rb_ractor_stdout_set(write_io);
+                    if (stdout_binmode) rb_io_binmode(rb_stdout);
+                }
+                fmode = FMODE_READABLE;
+                if (!ARGF.binmode) {
+                    fmode |= DEFAULT_TEXTMODE;
+                }
+                ARGF.current_file = prep_io(fr, fmode, rb_cFile, fn);
+                if (!NIL_P(write_io)) {
+                    rb_io_set_write_io(ARGF.current_file, write_io);
+                }
+                RB_GC_GUARD(filename);
+            }
+            if (ARGF.binmode) rb_io_ascii8bit_binmode(ARGF.current_file);
+            GetOpenFile(ARGF.current_file, fptr);
+            if (ARGF.encs.enc) {
+                fptr->encs = ARGF.encs;
                 clear_codeconv(fptr);
-	    }
-	    else {
-		fptr->encs.ecflags &= ~ECONV_NEWLINE_DECORATOR_MASK;
-		if (!ARGF.binmode) {
-		    fptr->encs.ecflags |= ECONV_DEFAULT_NEWLINE_DECORATOR;
+            }
+            else {
+                fptr->encs.ecflags &= ~ECONV_NEWLINE_DECORATOR_MASK;
+                if (!ARGF.binmode) {
+                    fptr->encs.ecflags |= ECONV_DEFAULT_NEWLINE_DECORATOR;
 #ifdef TEXTMODE_NEWLINE_DECORATOR_ON_WRITE
-		    fptr->encs.ecflags |= TEXTMODE_NEWLINE_DECORATOR_ON_WRITE;
+                    fptr->encs.ecflags |= TEXTMODE_NEWLINE_DECORATOR_ON_WRITE;
 #endif
-		}
-	    }
-	    ARGF.next_p = 0;
-	}
-	else {
-	    ARGF.next_p = 1;
-	    return FALSE;
-	}
+                }
+            }
+            ARGF.next_p = 0;
+        }
+        else {
+            ARGF.next_p = 1;
+            return FALSE;
+        }
     }
     else if (ARGF.next_p == -1) {
-	ARGF.current_file = rb_stdin;
-	ARGF.filename = rb_str_new2("-");
-	if (ARGF.inplace) {
-	    rb_warn("Can't do inplace edit for stdio");
-	    rb_ractor_stdout_set(orig_stdout);
-	}
+        ARGF.current_file = rb_stdin;
+        ARGF.filename = rb_str_new2("-");
+        if (ARGF.inplace) {
+            rb_warn("Can't do inplace edit for stdio");
+            rb_ractor_stdout_set(orig_stdout);
+        }
     }
     if (ARGF.init_p == -1) ARGF.init_p = 1;
     return TRUE;
@@ -9588,24 +10180,24 @@ argf_getline(int argc, VALUE *argv, VALUE argf)
   retry:
     if (!next_argv()) return Qnil;
     if (ARGF_GENERIC_INPUT_P()) {
-	line = forward_current(idGets, argc, argv);
+        line = forward_current(idGets, argc, argv);
     }
     else {
-	if (argc == 0 && rb_rs == rb_default_rs) {
-	    line = rb_io_gets(ARGF.current_file);
-	}
-	else {
-	    line = rb_io_getline(argc, argv, ARGF.current_file);
-	}
-	if (NIL_P(line) && ARGF.next_p != -1) {
-	    argf_close(argf);
-	    ARGF.next_p = 1;
-	    goto retry;
-	}
+        if (argc == 0 && rb_rs == rb_default_rs) {
+            line = rb_io_gets(ARGF.current_file);
+        }
+        else {
+            line = rb_io_getline(argc, argv, ARGF.current_file);
+        }
+        if (NIL_P(line) && ARGF.next_p != -1) {
+            argf_close(argf);
+            ARGF.next_p = 1;
+            goto retry;
+        }
     }
     if (!NIL_P(line)) {
-	ARGF.lineno = ++lineno;
-	ARGF.last_lineno = ARGF.lineno;
+        ARGF.lineno = ++lineno;
+        ARGF.last_lineno = ARGF.lineno;
     }
     return line;
 }
@@ -9625,6 +10217,12 @@ argf_lineno_setter(VALUE val, ID id, VALUE *var)
     ARGF.last_lineno = ARGF.lineno = n;
 }
 
+void
+rb_reset_argf_lineno(long n)
+{
+    ARGF.last_lineno = ARGF.lineno = n;
+}
+
 static VALUE argf_gets(int, VALUE *, VALUE);
 
 /*
@@ -9664,7 +10262,7 @@ static VALUE
 rb_f_gets(int argc, VALUE *argv, VALUE recv)
 {
     if (recv == argf) {
-	return argf_gets(argc, argv, argf);
+        return argf_gets(argc, argv, argf);
     }
     return forward(argf, idGets, argc, argv);
 }
@@ -9675,10 +10273,10 @@ rb_f_gets(int argc, VALUE *argv, VALUE recv)
  *     ARGF.gets(limit [, getline_args])      -> string or nil
  *     ARGF.gets(sep, limit [, getline_args]) -> string or nil
  *
- *  Returns the next line from the current file in +ARGF+.
+ *  Returns the next line from the current file in ARGF.
  *
  *  By default lines are assumed to be separated by <code>$/</code>;
- *  to use a different character as a separator, supply it as a +String+
+ *  to use a different character as a separator, supply it as a String
  *  for the _sep_ argument.
  *
  *  The optional _limit_ argument specifies how many characters of each line
@@ -9704,21 +10302,21 @@ rb_gets(void)
     VALUE line;
 
     if (rb_rs != rb_default_rs) {
-	return rb_f_gets(0, 0, argf);
+        return rb_f_gets(0, 0, argf);
     }
 
   retry:
     if (!next_argv()) return Qnil;
     line = rb_io_gets(ARGF.current_file);
     if (NIL_P(line) && ARGF.next_p != -1) {
-	rb_io_close(ARGF.current_file);
-	ARGF.next_p = 1;
-	goto retry;
+        rb_io_close(ARGF.current_file);
+        ARGF.next_p = 1;
+        goto retry;
     }
     rb_lastline_set(line);
     if (!NIL_P(line)) {
-	ARGF.lineno++;
-	ARGF.last_lineno = ARGF.lineno;
+        ARGF.lineno++;
+        ARGF.last_lineno = ARGF.lineno;
     }
 
     return line;
@@ -9728,9 +10326,9 @@ static VALUE argf_readline(int, VALUE *, VALUE);
 
 /*
  *  call-seq:
- *    readline(sep = $/, **line_opts)   -> string
- *    readline(limit, **line_opts)      -> string
- *    readline(sep, limit, **line_opts) -> string
+ *    readline(sep = $/, chomp: false)   -> string
+ *    readline(limit, chomp: false)      -> string
+ *    readline(sep, limit, chomp: false) -> string
  *
  *  Equivalent to method Kernel#gets, except that it raises an exception
  *  if called at end-of-stream:
@@ -9739,13 +10337,15 @@ static VALUE argf_readline(int, VALUE *, VALUE);
  *    ["First line\n", "Second line\n", "\n", "Fourth line\n", "Fifth line\n"]
  *    in `readline': end of file reached (EOFError)
  *
+ *  Optional keyword argument +chomp+ specifies whether line separators
+ *  are to be omitted.
  */
 
 static VALUE
 rb_f_readline(int argc, VALUE *argv, VALUE recv)
 {
     if (recv == argf) {
-	return argf_readline(argc, argv, argf);
+        return argf_readline(argc, argv, argf);
     }
     return forward(argf, rb_intern("readline"), argc, argv);
 }
@@ -9757,16 +10357,16 @@ rb_f_readline(int argc, VALUE *argv, VALUE recv)
  *     ARGF.readline(limit)      -> string
  *     ARGF.readline(sep, limit) -> string
  *
- *  Returns the next line from the current file in +ARGF+.
+ *  Returns the next line from the current file in ARGF.
  *
  *  By default lines are assumed to be separated by <code>$/</code>;
- *  to use a different character as a separator, supply it as a +String+
+ *  to use a different character as a separator, supply it as a String
  *  for the _sep_ argument.
  *
  *  The optional _limit_ argument specifies how many characters of each line
  *  to return. By default all characters are returned.
  *
- *  An +EOFError+ is raised at the end of the file.
+ *  An EOFError is raised at the end of the file.
  */
 static VALUE
 argf_readline(int argc, VALUE *argv, VALUE argf)
@@ -9777,7 +10377,7 @@ argf_readline(int argc, VALUE *argv, VALUE argf)
     ARGF_FORWARD(argc, argv);
     line = argf_gets(argc, argv, argf);
     if (NIL_P(line)) {
-	rb_eof_error();
+        rb_eof_error();
     }
 
     return line;
@@ -9787,13 +10387,13 @@ static VALUE argf_readlines(int, VALUE *, VALUE);
 
 /*
  *  call-seq:
- *    readlines(sep = $/, **line_opts)   -> array
- *    readlines(limit, **line_opts)       -> array
- *    readlines(sep, limit, **line_opts) -> array
+ *    readlines(sep = $/, chomp: false, **enc_opts)   -> array
+ *    readlines(limit, chomp: false, **enc_opts)       -> array
+ *    readlines(sep, limit, chomp: false, **enc_opts) -> array
  *
  *  Returns an array containing the lines returned by calling
- *  Kernel#gets until the end-of-file is reached;
- *  (see {Lines}[rdoc-ref:IO@Lines]).
+ *  Kernel#gets until the end-of-stream is reached;
+ *  (see {Line IO}[rdoc-ref:IO@Line+IO]).
  *
  *  With only string argument +sep+ given,
  *  returns the remaining lines as determined by line separator +sep+,
@@ -9832,39 +10432,38 @@ static VALUE argf_readlines(int, VALUE *, VALUE);
  *  With arguments +sep+ and +limit+ given, combines the two behaviors;
  *  see {Line Separator and Line Limit}[rdoc-ref:IO@Line+Separator+and+Line+Limit].
  *
- *  For all forms above, optional keyword arguments specify:
- *
- *  - {Line Options}[rdoc-ref:IO@Line+Options].
- *  - {Encoding options}[rdoc-ref:encodings.rdoc@Encoding+Options].
- *
- *  Examples:
+ *  Optional keyword argument +chomp+ specifies whether line separators
+ *  are to be omitted:
  *
  *    $ cat t.txt | ruby -e "p readlines(chomp: true)"
  *    ["First line", "Second line", "", "Fourth line", "Fifth line"]
  *
+ *  Optional keyword arguments +enc_opts+ specify encoding options;
+ *  see {Encoding options}[rdoc-ref:encodings.rdoc@Encoding+Options].
+ *
  */
 
 static VALUE
 rb_f_readlines(int argc, VALUE *argv, VALUE recv)
 {
     if (recv == argf) {
-	return argf_readlines(argc, argv, argf);
+        return argf_readlines(argc, argv, argf);
     }
     return forward(argf, rb_intern("readlines"), argc, argv);
 }
 
 /*
  *  call-seq:
- *     ARGF.readlines(sep=$/)     -> array
+ *     ARGF.readlines(sep = $/)     -> array
  *     ARGF.readlines(limit)      -> array
  *     ARGF.readlines(sep, limit) -> array
  *
- *     ARGF.to_a(sep=$/)     -> array
+ *     ARGF.to_a(sep = $/)     -> array
  *     ARGF.to_a(limit)      -> array
  *     ARGF.to_a(sep, limit) -> array
  *
- *  Reads +ARGF+'s current file in its entirety, returning an +Array+ of its
- *  lines, one line per element. Lines are assumed to be separated by _sep_.
+ *  Reads each file in ARGF in its entirety, returning an Array containing
+ *  lines from the files. Lines are assumed to be separated by _sep_.
  *
  *     lines = ARGF.readlines
  *     lines[0]                #=> "This is line one\n"
@@ -9877,17 +10476,17 @@ argf_readlines(int argc, VALUE *argv, VALUE argf)
 
     ary = rb_ary_new();
     while (next_argv()) {
-	if (ARGF_GENERIC_INPUT_P()) {
-	    lines = forward_current(rb_intern("readlines"), argc, argv);
-	}
-	else {
-	    lines = rb_io_readlines(argc, argv, ARGF.current_file);
-	    argf_close(argf);
-	}
-	ARGF.next_p = 1;
-	rb_ary_concat(ary, lines);
-	ARGF.lineno = lineno + RARRAY_LEN(ary);
-	ARGF.last_lineno = ARGF.lineno;
+        if (ARGF_GENERIC_INPUT_P()) {
+            lines = forward_current(rb_intern("readlines"), argc, argv);
+        }
+        else {
+            lines = rb_io_readlines(argc, argv, ARGF.current_file);
+            argf_close(argf);
+        }
+        ARGF.next_p = 1;
+        rb_ary_concat(ary, lines);
+        ARGF.lineno = lineno + RARRAY_LEN(ary);
+        ARGF.last_lineno = ARGF.lineno;
     }
     ARGF.init_p = 0;
     return ary;
@@ -9952,63 +10551,63 @@ select_internal(VALUE read, VALUE write, VALUE except, struct timeval *tp, rb_fd
     struct timeval timerec;
 
     if (!NIL_P(read)) {
-	Check_Type(read, T_ARRAY);
-	for (i=0; i<RARRAY_LEN(read); i++) {
-	    GetOpenFile(rb_io_get_io(RARRAY_AREF(read, i)), fptr);
-	    rb_fd_set(fptr->fd, &fds[0]);
-	    if (READ_DATA_PENDING(fptr) || READ_CHAR_PENDING(fptr)) { /* check for buffered data */
-		pending++;
-		rb_fd_set(fptr->fd, &fds[3]);
-	    }
-	    if (max < fptr->fd) max = fptr->fd;
-	}
-	if (pending) {		/* no blocking if there's buffered data */
-	    timerec.tv_sec = timerec.tv_usec = 0;
-	    tp = &timerec;
-	}
-	rp = &fds[0];
+        Check_Type(read, T_ARRAY);
+        for (i=0; i<RARRAY_LEN(read); i++) {
+            GetOpenFile(rb_io_get_io(RARRAY_AREF(read, i)), fptr);
+            rb_fd_set(fptr->fd, &fds[0]);
+            if (READ_DATA_PENDING(fptr) || READ_CHAR_PENDING(fptr)) { /* check for buffered data */
+                pending++;
+                rb_fd_set(fptr->fd, &fds[3]);
+            }
+            if (max < fptr->fd) max = fptr->fd;
+        }
+        if (pending) {		/* no blocking if there's buffered data */
+            timerec.tv_sec = timerec.tv_usec = 0;
+            tp = &timerec;
+        }
+        rp = &fds[0];
     }
     else
-	rp = 0;
+        rp = 0;
 
     if (!NIL_P(write)) {
-	Check_Type(write, T_ARRAY);
-	for (i=0; i<RARRAY_LEN(write); i++) {
+        Check_Type(write, T_ARRAY);
+        for (i=0; i<RARRAY_LEN(write); i++) {
             VALUE write_io = GetWriteIO(rb_io_get_io(RARRAY_AREF(write, i)));
-	    GetOpenFile(write_io, fptr);
-	    rb_fd_set(fptr->fd, &fds[1]);
-	    if (max < fptr->fd) max = fptr->fd;
-	}
-	wp = &fds[1];
+            GetOpenFile(write_io, fptr);
+            rb_fd_set(fptr->fd, &fds[1]);
+            if (max < fptr->fd) max = fptr->fd;
+        }
+        wp = &fds[1];
     }
     else
-	wp = 0;
+        wp = 0;
 
     if (!NIL_P(except)) {
-	Check_Type(except, T_ARRAY);
-	for (i=0; i<RARRAY_LEN(except); i++) {
+        Check_Type(except, T_ARRAY);
+        for (i=0; i<RARRAY_LEN(except); i++) {
             VALUE io = rb_io_get_io(RARRAY_AREF(except, i));
             VALUE write_io = GetWriteIO(io);
-	    GetOpenFile(io, fptr);
-	    rb_fd_set(fptr->fd, &fds[2]);
-	    if (max < fptr->fd) max = fptr->fd;
+            GetOpenFile(io, fptr);
+            rb_fd_set(fptr->fd, &fds[2]);
+            if (max < fptr->fd) max = fptr->fd;
             if (io != write_io) {
                 GetOpenFile(write_io, fptr);
                 rb_fd_set(fptr->fd, &fds[2]);
                 if (max < fptr->fd) max = fptr->fd;
             }
-	}
-	ep = &fds[2];
+        }
+        ep = &fds[2];
     }
     else {
-	ep = 0;
+        ep = 0;
     }
 
     max++;
 
     n = rb_thread_fd_select(max, rp, wp, ep, tp);
     if (n < 0) {
-	rb_sys_fail(0);
+        rb_sys_fail(0);
     }
     if (!pending && n == 0) return Qnil; /* returns nil on timeout */
 
@@ -10018,48 +10617,48 @@ select_internal(VALUE read, VALUE write, VALUE except, struct timeval *tp, rb_fd
     rb_ary_push(res, ep?rb_ary_new():rb_ary_new2(0));
 
     if (rp) {
-	list = RARRAY_AREF(res, 0);
-	for (i=0; i< RARRAY_LEN(read); i++) {
-	    VALUE obj = rb_ary_entry(read, i);
-	    VALUE io = rb_io_get_io(obj);
-	    GetOpenFile(io, fptr);
-	    if (rb_fd_isset(fptr->fd, &fds[0]) ||
-		rb_fd_isset(fptr->fd, &fds[3])) {
-		rb_ary_push(list, obj);
-	    }
-	}
+        list = RARRAY_AREF(res, 0);
+        for (i=0; i< RARRAY_LEN(read); i++) {
+            VALUE obj = rb_ary_entry(read, i);
+            VALUE io = rb_io_get_io(obj);
+            GetOpenFile(io, fptr);
+            if (rb_fd_isset(fptr->fd, &fds[0]) ||
+                rb_fd_isset(fptr->fd, &fds[3])) {
+                rb_ary_push(list, obj);
+            }
+        }
     }
 
     if (wp) {
-	list = RARRAY_AREF(res, 1);
-	for (i=0; i< RARRAY_LEN(write); i++) {
-	    VALUE obj = rb_ary_entry(write, i);
-	    VALUE io = rb_io_get_io(obj);
-	    VALUE write_io = GetWriteIO(io);
-	    GetOpenFile(write_io, fptr);
-	    if (rb_fd_isset(fptr->fd, &fds[1])) {
-		rb_ary_push(list, obj);
-	    }
-	}
+        list = RARRAY_AREF(res, 1);
+        for (i=0; i< RARRAY_LEN(write); i++) {
+            VALUE obj = rb_ary_entry(write, i);
+            VALUE io = rb_io_get_io(obj);
+            VALUE write_io = GetWriteIO(io);
+            GetOpenFile(write_io, fptr);
+            if (rb_fd_isset(fptr->fd, &fds[1])) {
+                rb_ary_push(list, obj);
+            }
+        }
     }
 
     if (ep) {
-	list = RARRAY_AREF(res, 2);
-	for (i=0; i< RARRAY_LEN(except); i++) {
-	    VALUE obj = rb_ary_entry(except, i);
-	    VALUE io = rb_io_get_io(obj);
-	    VALUE write_io = GetWriteIO(io);
-	    GetOpenFile(io, fptr);
-	    if (rb_fd_isset(fptr->fd, &fds[2])) {
-		rb_ary_push(list, obj);
-	    }
-	    else if (io != write_io) {
-		GetOpenFile(write_io, fptr);
-		if (rb_fd_isset(fptr->fd, &fds[2])) {
-		    rb_ary_push(list, obj);
-		}
-	    }
-	}
+        list = RARRAY_AREF(res, 2);
+        for (i=0; i< RARRAY_LEN(except); i++) {
+            VALUE obj = rb_ary_entry(except, i);
+            VALUE io = rb_io_get_io(obj);
+            VALUE write_io = GetWriteIO(io);
+            GetOpenFile(io, fptr);
+            if (rb_fd_isset(fptr->fd, &fds[2])) {
+                rb_ary_push(list, obj);
+            }
+            else if (io != write_io) {
+                GetOpenFile(write_io, fptr);
+                if (rb_fd_isset(fptr->fd, &fds[2])) {
+                    rb_ary_push(list, obj);
+                }
+            }
+        }
     }
 
     return res;			/* returns an empty array on interrupt */
@@ -10086,7 +10685,7 @@ select_end(VALUE arg)
     int i;
 
     for (i = 0; i < numberof(p->fdsets); ++i)
-	rb_fd_term(&p->fdsets[i]);
+        rb_fd_term(&p->fdsets[i]);
     return Qnil;
 }
 
@@ -10097,8 +10696,8 @@ static VALUE sym_normal,   sym_sequential, sym_random,
 struct io_advise_struct {
     int fd;
     int advice;
-    off_t offset;
-    off_t len;
+    rb_off_t offset;
+    rb_off_t len;
 };
 
 static VALUE
@@ -10113,39 +10712,39 @@ io_advise_sym_to_const(VALUE sym)
 {
 #ifdef POSIX_FADV_NORMAL
     if (sym == sym_normal)
-	return INT2NUM(POSIX_FADV_NORMAL);
+        return INT2NUM(POSIX_FADV_NORMAL);
 #endif
 
 #ifdef POSIX_FADV_RANDOM
     if (sym == sym_random)
-	return INT2NUM(POSIX_FADV_RANDOM);
+        return INT2NUM(POSIX_FADV_RANDOM);
 #endif
 
 #ifdef POSIX_FADV_SEQUENTIAL
     if (sym == sym_sequential)
-	return INT2NUM(POSIX_FADV_SEQUENTIAL);
+        return INT2NUM(POSIX_FADV_SEQUENTIAL);
 #endif
 
 #ifdef POSIX_FADV_WILLNEED
     if (sym == sym_willneed)
-	return INT2NUM(POSIX_FADV_WILLNEED);
+        return INT2NUM(POSIX_FADV_WILLNEED);
 #endif
 
 #ifdef POSIX_FADV_DONTNEED
     if (sym == sym_dontneed)
-	return INT2NUM(POSIX_FADV_DONTNEED);
+        return INT2NUM(POSIX_FADV_DONTNEED);
 #endif
 
 #ifdef POSIX_FADV_NOREUSE
     if (sym == sym_noreuse)
-	return INT2NUM(POSIX_FADV_NOREUSE);
+        return INT2NUM(POSIX_FADV_NOREUSE);
 #endif
 
     return Qnil;
 }
 
 static VALUE
-do_io_advise(rb_io_t *fptr, VALUE advice, off_t offset, off_t len)
+do_io_advise(rb_io_t *fptr, VALUE advice, rb_off_t offset, rb_off_t len)
 {
     int rv;
     struct io_advise_struct ias;
@@ -10158,7 +10757,7 @@ do_io_advise(rb_io_t *fptr, VALUE advice, off_t offset, off_t len)
      * silently ignore it. Because IO::advise is only hint.
      */
     if (NIL_P(num_adv))
-	return Qnil;
+        return Qnil;
 
     ias.fd     = fptr->fd;
     ias.advice = NUM2INT(num_adv);
@@ -10167,14 +10766,14 @@ do_io_advise(rb_io_t *fptr, VALUE advice, off_t offset, off_t len)
 
     rv = (int)rb_thread_io_blocking_region(io_advise_internal, &ias, fptr->fd);
     if (rv && rv != ENOSYS) {
-	/* posix_fadvise(2) doesn't set errno. On success it returns 0; otherwise
-	   it returns the error code. */
-	VALUE message = rb_sprintf("%"PRIsVALUE" "
-				   "(%"PRI_OFFT_PREFIX"d, "
-				   "%"PRI_OFFT_PREFIX"d, "
-				   "%"PRIsVALUE")",
-				   fptr->pathv, offset, len, advice);
-	rb_syserr_fail_str(rv, message);
+        /* posix_fadvise(2) doesn't set errno. On success it returns 0; otherwise
+           it returns the error code. */
+        VALUE message = rb_sprintf("%"PRIsVALUE" "
+                                   "(%"PRI_OFFT_PREFIX"d, "
+                                   "%"PRI_OFFT_PREFIX"d, "
+                                   "%"PRIsVALUE")",
+                                   fptr->pathv, offset, len, advice);
+        rb_syserr_fail_str(rv, message);
     }
 
     return Qnil;
@@ -10186,15 +10785,15 @@ static void
 advice_arg_check(VALUE advice)
 {
     if (!SYMBOL_P(advice))
-	rb_raise(rb_eTypeError, "advice must be a Symbol");
+        rb_raise(rb_eTypeError, "advice must be a Symbol");
 
     if (advice != sym_normal &&
-	advice != sym_sequential &&
-	advice != sym_random &&
-	advice != sym_willneed &&
-	advice != sym_dontneed &&
-	advice != sym_noreuse) {
-	rb_raise(rb_eNotImpError, "Unsupported advice: %+"PRIsVALUE, advice);
+        advice != sym_sequential &&
+        advice != sym_random &&
+        advice != sym_willneed &&
+        advice != sym_dontneed &&
+        advice != sym_noreuse) {
+        rb_raise(rb_eNotImpError, "Unsupported advice: %+"PRIsVALUE, advice);
     }
 }
 
@@ -10235,7 +10834,7 @@ static VALUE
 rb_io_advise(int argc, VALUE *argv, VALUE io)
 {
     VALUE advice, offset, len;
-    off_t off, l;
+    rb_off_t off, l;
     rb_io_t *fptr;
 
     rb_scan_args(argc, argv, "12", &advice, &offset, &len);
@@ -10407,6 +11006,13 @@ rb_io_advise(int argc, VALUE *argv, VALUE io)
 static VALUE
 rb_f_select(int argc, VALUE *argv, VALUE obj)
 {
+    VALUE scheduler = rb_fiber_scheduler_current();
+    if (scheduler != Qnil) {
+        // It's optionally supported.
+        VALUE result = rb_fiber_scheduler_io_selectv(scheduler, argc, argv);
+        if (!UNDEF_P(result)) return result;
+    }
+
     VALUE timeout;
     struct select_args args;
     struct timeval timerec;
@@ -10414,15 +11020,15 @@ rb_f_select(int argc, VALUE *argv, VALUE obj)
 
     rb_scan_args(argc, argv, "13", &args.read, &args.write, &args.except, &timeout);
     if (NIL_P(timeout)) {
-	args.timeout = 0;
+        args.timeout = 0;
     }
     else {
-	timerec = rb_time_interval(timeout);
-	args.timeout = &timerec;
+        timerec = rb_time_interval(timeout);
+        args.timeout = &timerec;
     }
 
     for (i = 0; i < numberof(args.fdsets); ++i)
-	rb_fd_init(&args.fdsets[i]);
+        rb_fd_init(&args.fdsets[i]);
 
     return rb_ensure(select_call, (VALUE)&args, select_end, (VALUE)&args);
 }
@@ -10474,15 +11080,15 @@ linux_iocparm_len(ioctl_req_t cmd)
     long len;
 
     if ((cmd & 0xFFFF0000) == 0) {
-	/* legacy and unstructured ioctl number. */
-	return DEFAULT_IOCTL_NARG_LEN;
+        /* legacy and unstructured ioctl number. */
+        return DEFAULT_IOCTL_NARG_LEN;
     }
 
     len = _IOC_SIZE(cmd);
 
     /* paranoia check for silly drivers which don't keep ioctl convention */
     if (len < DEFAULT_IOCTL_NARG_LEN)
-	len = DEFAULT_IOCTL_NARG_LEN;
+        len = DEFAULT_IOCTL_NARG_LEN;
 
     return len;
 }
@@ -10528,113 +11134,113 @@ fcntl_narg_len(ioctl_req_t cmd)
     switch (cmd) {
 #ifdef F_DUPFD
       case F_DUPFD:
-	len = sizeof(fcntl_arg_t);
-	break;
+        len = sizeof(fcntl_arg_t);
+        break;
 #endif
 #ifdef F_DUP2FD /* bsd specific */
       case F_DUP2FD:
-	len = sizeof(int);
-	break;
+        len = sizeof(int);
+        break;
 #endif
 #ifdef F_DUPFD_CLOEXEC /* linux specific */
       case F_DUPFD_CLOEXEC:
-	len = sizeof(fcntl_arg_t);
-	break;
+        len = sizeof(fcntl_arg_t);
+        break;
 #endif
 #ifdef F_GETFD
       case F_GETFD:
-	len = 1;
-	break;
+        len = 1;
+        break;
 #endif
 #ifdef F_SETFD
       case F_SETFD:
-	len = sizeof(fcntl_arg_t);
-	break;
+        len = sizeof(fcntl_arg_t);
+        break;
 #endif
 #ifdef F_GETFL
       case F_GETFL:
-	len = 1;
-	break;
+        len = 1;
+        break;
 #endif
 #ifdef F_SETFL
       case F_SETFL:
-	len = sizeof(fcntl_arg_t);
-	break;
+        len = sizeof(fcntl_arg_t);
+        break;
 #endif
 #ifdef F_GETOWN
       case F_GETOWN:
-	len = 1;
-	break;
+        len = 1;
+        break;
 #endif
 #ifdef F_SETOWN
       case F_SETOWN:
-	len = sizeof(fcntl_arg_t);
-	break;
+        len = sizeof(fcntl_arg_t);
+        break;
 #endif
 #ifdef F_GETOWN_EX /* linux specific */
       case F_GETOWN_EX:
-	len = sizeof(struct f_owner_ex);
-	break;
+        len = sizeof(struct f_owner_ex);
+        break;
 #endif
 #ifdef F_SETOWN_EX /* linux specific */
       case F_SETOWN_EX:
-	len = sizeof(struct f_owner_ex);
-	break;
+        len = sizeof(struct f_owner_ex);
+        break;
 #endif
 #ifdef F_GETLK
       case F_GETLK:
-	len = sizeof(struct flock);
-	break;
+        len = sizeof(struct flock);
+        break;
 #endif
 #ifdef F_SETLK
       case F_SETLK:
-	len = sizeof(struct flock);
-	break;
+        len = sizeof(struct flock);
+        break;
 #endif
 #ifdef F_SETLKW
       case F_SETLKW:
-	len = sizeof(struct flock);
-	break;
+        len = sizeof(struct flock);
+        break;
 #endif
 #ifdef F_READAHEAD /* bsd specific */
       case F_READAHEAD:
-	len = sizeof(int);
-	break;
+        len = sizeof(int);
+        break;
 #endif
 #ifdef F_RDAHEAD /* Darwin specific */
       case F_RDAHEAD:
-	len = sizeof(int);
-	break;
+        len = sizeof(int);
+        break;
 #endif
 #ifdef F_GETSIG /* linux specific */
       case F_GETSIG:
-	len = 1;
-	break;
+        len = 1;
+        break;
 #endif
 #ifdef F_SETSIG /* linux specific */
       case F_SETSIG:
-	len = sizeof(fcntl_arg_t);
-	break;
+        len = sizeof(fcntl_arg_t);
+        break;
 #endif
 #ifdef F_GETLEASE /* linux specific */
       case F_GETLEASE:
-	len = 1;
-	break;
+        len = 1;
+        break;
 #endif
 #ifdef F_SETLEASE /* linux specific */
       case F_SETLEASE:
-	len = sizeof(fcntl_arg_t);
-	break;
+        len = sizeof(fcntl_arg_t);
+        break;
 #endif
 #ifdef F_NOTIFY /* linux specific */
       case F_NOTIFY:
-	len = sizeof(fcntl_arg_t);
-	break;
+        len = sizeof(fcntl_arg_t);
+        break;
 #endif
 
       default:
-	len = 256;
-	break;
+        len = 256;
+        break;
     }
 
     return len;
@@ -10656,40 +11262,40 @@ setup_narg(ioctl_req_t cmd, VALUE *argp, long (*narg_len)(ioctl_req_t))
     VALUE arg = *argp;
 
     if (!RTEST(arg)) {
-	narg = 0;
+        narg = 0;
     }
     else if (FIXNUM_P(arg)) {
-	narg = FIX2LONG(arg);
+        narg = FIX2LONG(arg);
     }
     else if (arg == Qtrue) {
-	narg = 1;
+        narg = 1;
     }
     else {
-	VALUE tmp = rb_check_string_type(arg);
-
-	if (NIL_P(tmp)) {
-	    narg = NUM2LONG(arg);
-	}
-	else {
-	    char *ptr;
-	    long len, slen;
-
-	    *argp = arg = tmp;
-	    len = narg_len(cmd);
-	    rb_str_modify(arg);
-
-	    slen = RSTRING_LEN(arg);
-	    /* expand for data + sentinel. */
-	    if (slen < len+1) {
-		rb_str_resize(arg, len+1);
-		MEMZERO(RSTRING_PTR(arg)+slen, char, len-slen);
-		slen = len+1;
-	    }
-	    /* a little sanity check here */
-	    ptr = RSTRING_PTR(arg);
-	    ptr[slen - 1] = NARG_SENTINEL;
-	    narg = (long)(SIGNED_VALUE)ptr;
-	}
+        VALUE tmp = rb_check_string_type(arg);
+
+        if (NIL_P(tmp)) {
+            narg = NUM2LONG(arg);
+        }
+        else {
+            char *ptr;
+            long len, slen;
+
+            *argp = arg = tmp;
+            len = narg_len(cmd);
+            rb_str_modify(arg);
+
+            slen = RSTRING_LEN(arg);
+            /* expand for data + sentinel. */
+            if (slen < len+1) {
+                rb_str_resize(arg, len+1);
+                MEMZERO(RSTRING_PTR(arg)+slen, char, len-slen);
+                slen = len+1;
+            }
+            /* a little sanity check here */
+            ptr = RSTRING_PTR(arg);
+            ptr[slen - 1] = NARG_SENTINEL;
+            narg = (long)(SIGNED_VALUE)ptr;
+        }
     }
 
     return narg;
@@ -10700,12 +11306,12 @@ finish_narg(int retval, VALUE arg, const rb_io_t *fptr)
 {
     if (retval < 0) rb_sys_fail_path(fptr->pathv);
     if (RB_TYPE_P(arg, T_STRING)) {
-	char *ptr;
-	long slen;
-	RSTRING_GETMEM(arg, ptr, slen);
-	if (ptr[slen-1] != NARG_SENTINEL)
-	    rb_raise(rb_eArgError, "return value overflowed string");
-	ptr[slen-1] = '\0';
+        char *ptr;
+        long slen;
+        RSTRING_GETMEM(arg, ptr, slen);
+        if (ptr[slen-1] != NARG_SENTINEL)
+            rb_raise(rb_eArgError, "return value overflowed string");
+        ptr[slen-1] = '\0';
     }
 
     return INT2NUM(retval);
@@ -10770,7 +11376,7 @@ nogvl_fcntl(void *ptr)
 
 #if defined(F_DUPFD)
     if (arg->cmd == F_DUPFD)
-	return (VALUE)rb_cloexec_fcntl_dupfd(arg->fd, (int)arg->narg);
+        return (VALUE)rb_cloexec_fcntl_dupfd(arg->fd, (int)arg->narg);
 #endif
     return (VALUE)fcntl(arg->fd, arg->cmd, arg->narg);
 }
@@ -10787,15 +11393,15 @@ do_fcntl(int fd, int cmd, long narg)
 
     retval = (int)rb_thread_io_blocking_region(nogvl_fcntl, &arg, fd);
     if (retval != -1) {
-	switch (cmd) {
+        switch (cmd) {
 #if defined(F_DUPFD)
-	  case F_DUPFD:
+          case F_DUPFD:
 #endif
 #if defined(F_DUPFD_CLOEXEC)
-	  case F_DUPFD_CLOEXEC:
+          case F_DUPFD_CLOEXEC:
 #endif
-	    rb_update_max_fd(retval);
-	}
+            rb_update_max_fd(retval);
+        }
     }
 
     return retval;
@@ -10913,52 +11519,52 @@ rb_f_syscall(int argc, VALUE *argv, VALUE _)
     }
 
     if (argc == 0)
-	rb_raise(rb_eArgError, "too few arguments for syscall");
+        rb_raise(rb_eArgError, "too few arguments for syscall");
     if (argc > numberof(arg))
-	rb_raise(rb_eArgError, "too many arguments for syscall");
+        rb_raise(rb_eArgError, "too many arguments for syscall");
     num = NUM2SYSCALLID(argv[0]); ++argv;
     for (i = argc - 1; i--; ) {
-	VALUE v = rb_check_string_type(argv[i]);
+        VALUE v = rb_check_string_type(argv[i]);
 
-	if (!NIL_P(v)) {
-	    SafeStringValue(v);
-	    rb_str_modify(v);
-	    arg[i] = (VALUE)StringValueCStr(v);
-	}
-	else {
-	    arg[i] = (VALUE)NUM2LONG(argv[i]);
-	}
+        if (!NIL_P(v)) {
+            SafeStringValue(v);
+            rb_str_modify(v);
+            arg[i] = (VALUE)StringValueCStr(v);
+        }
+        else {
+            arg[i] = (VALUE)NUM2LONG(argv[i]);
+        }
     }
 
     switch (argc) {
       case 1:
-	retval = SYSCALL(num);
-	break;
+        retval = SYSCALL(num);
+        break;
       case 2:
-	retval = SYSCALL(num, arg[0]);
-	break;
+        retval = SYSCALL(num, arg[0]);
+        break;
       case 3:
-	retval = SYSCALL(num, arg[0],arg[1]);
-	break;
+        retval = SYSCALL(num, arg[0],arg[1]);
+        break;
       case 4:
-	retval = SYSCALL(num, arg[0],arg[1],arg[2]);
-	break;
+        retval = SYSCALL(num, arg[0],arg[1],arg[2]);
+        break;
       case 5:
-	retval = SYSCALL(num, arg[0],arg[1],arg[2],arg[3]);
-	break;
+        retval = SYSCALL(num, arg[0],arg[1],arg[2],arg[3]);
+        break;
       case 6:
-	retval = SYSCALL(num, arg[0],arg[1],arg[2],arg[3],arg[4]);
-	break;
+        retval = SYSCALL(num, arg[0],arg[1],arg[2],arg[3],arg[4]);
+        break;
       case 7:
-	retval = SYSCALL(num, arg[0],arg[1],arg[2],arg[3],arg[4],arg[5]);
-	break;
+        retval = SYSCALL(num, arg[0],arg[1],arg[2],arg[3],arg[4],arg[5]);
+        break;
       case 8:
-	retval = SYSCALL(num, arg[0],arg[1],arg[2],arg[3],arg[4],arg[5],arg[6]);
-	break;
+        retval = SYSCALL(num, arg[0],arg[1],arg[2],arg[3],arg[4],arg[5],arg[6]);
+        break;
     }
 
     if (retval == -1)
-	rb_sys_fail(0);
+        rb_sys_fail(0);
     return RETVAL2NUM(retval);
 #undef SYSCALL
 #undef NUM2SYSCALLID
@@ -10990,51 +11596,51 @@ io_encoding_set(rb_io_t *fptr, VALUE v1, VALUE v2, VALUE opt)
     VALUE ecopts, tmp;
 
     if (!NIL_P(v2)) {
-	enc2 = find_encoding(v1);
-	tmp = rb_check_string_type(v2);
-	if (!NIL_P(tmp)) {
-	    if (RSTRING_LEN(tmp) == 1 && RSTRING_PTR(tmp)[0] == '-') {
-		/* Special case - "-" => no transcoding */
-		enc = enc2;
-		enc2 = NULL;
-	    }
-	    else
-		enc = find_encoding(v2);
-	    if (enc == enc2) {
-		/* Special case - "-" => no transcoding */
-		enc2 = NULL;
-	    }
-	}
-	else {
-	    enc = find_encoding(v2);
-	    if (enc == enc2) {
-		/* Special case - "-" => no transcoding */
-		enc2 = NULL;
-	    }
-	}
-	SET_UNIVERSAL_NEWLINE_DECORATOR_IF_ENC2(enc2, ecflags);
-	ecflags = rb_econv_prepare_options(opt, &ecopts, ecflags);
+        enc2 = find_encoding(v1);
+        tmp = rb_check_string_type(v2);
+        if (!NIL_P(tmp)) {
+            if (RSTRING_LEN(tmp) == 1 && RSTRING_PTR(tmp)[0] == '-') {
+                /* Special case - "-" => no transcoding */
+                enc = enc2;
+                enc2 = NULL;
+            }
+            else
+                enc = find_encoding(v2);
+            if (enc == enc2) {
+                /* Special case - "-" => no transcoding */
+                enc2 = NULL;
+            }
+        }
+        else {
+            enc = find_encoding(v2);
+            if (enc == enc2) {
+                /* Special case - "-" => no transcoding */
+                enc2 = NULL;
+            }
+        }
+        SET_UNIVERSAL_NEWLINE_DECORATOR_IF_ENC2(enc2, ecflags);
+        ecflags = rb_econv_prepare_options(opt, &ecopts, ecflags);
     }
     else {
-	if (NIL_P(v1)) {
-	    /* Set to default encodings */
-	    rb_io_ext_int_to_encs(NULL, NULL, &enc, &enc2, 0);
-	    SET_UNIVERSAL_NEWLINE_DECORATOR_IF_ENC2(enc2, ecflags);
+        if (NIL_P(v1)) {
+            /* Set to default encodings */
+            rb_io_ext_int_to_encs(NULL, NULL, &enc, &enc2, 0);
+            SET_UNIVERSAL_NEWLINE_DECORATOR_IF_ENC2(enc2, ecflags);
             ecopts = Qnil;
-	}
-	else {
-	    tmp = rb_check_string_type(v1);
-	    if (!NIL_P(tmp) && rb_enc_asciicompat(enc = rb_enc_get(tmp))) {
+        }
+        else {
+            tmp = rb_check_string_type(v1);
+            if (!NIL_P(tmp) && rb_enc_asciicompat(enc = rb_enc_get(tmp))) {
                 parse_mode_enc(RSTRING_PTR(tmp), enc, &enc, &enc2, NULL);
-		SET_UNIVERSAL_NEWLINE_DECORATOR_IF_ENC2(enc2, ecflags);
+                SET_UNIVERSAL_NEWLINE_DECORATOR_IF_ENC2(enc2, ecflags);
                 ecflags = rb_econv_prepare_options(opt, &ecopts, ecflags);
-	    }
-	    else {
-		rb_io_ext_int_to_encs(find_encoding(v1), NULL, &enc, &enc2, 0);
-		SET_UNIVERSAL_NEWLINE_DECORATOR_IF_ENC2(enc2, ecflags);
+            }
+            else {
+                rb_io_ext_int_to_encs(find_encoding(v1), NULL, &enc, &enc2, 0);
+                SET_UNIVERSAL_NEWLINE_DECORATOR_IF_ENC2(enc2, ecflags);
                 ecopts = Qnil;
-	    }
-	}
+            }
+        }
     }
     validate_enc_binmode(&fptr->mode, ecflags, enc, enc2);
     fptr->encs.enc = enc;
@@ -11166,9 +11772,9 @@ rb_io_s_pipe(int argc, VALUE *argv, VALUE klass)
     args[2] = INT2FIX(O_RDONLY);
     r = rb_protect(io_new_instance, (VALUE)args, &state);
     if (state) {
-	close(pipes[0]);
-	close(pipes[1]);
-	rb_jump_tag(state);
+        close(pipes[0]);
+        close(pipes[1]);
+        rb_jump_tag(state);
     }
     GetOpenFile(r, fptr);
 
@@ -11178,18 +11784,18 @@ rb_io_s_pipe(int argc, VALUE *argv, VALUE klass)
     ies_args.opt = opt;
     rb_protect(io_encoding_set_v, (VALUE)&ies_args, &state);
     if (state) {
-	close(pipes[1]);
+        close(pipes[1]);
         io_close(r);
-	rb_jump_tag(state);
+        rb_jump_tag(state);
     }
 
     args[1] = INT2NUM(pipes[1]);
     args[2] = INT2FIX(O_WRONLY);
     w = rb_protect(io_new_instance, (VALUE)args, &state);
     if (state) {
-	close(pipes[1]);
-	if (!NIL_P(r)) rb_io_close(r);
-	rb_jump_tag(state);
+        close(pipes[1]);
+        if (!NIL_P(r)) rb_io_close(r);
+        rb_jump_tag(state);
     }
     GetOpenFile(w, fptr2);
     rb_io_synchronized(fptr2);
@@ -11203,30 +11809,30 @@ rb_io_s_pipe(int argc, VALUE *argv, VALUE klass)
 
 #if DEFAULT_TEXTMODE
     if ((fptr->mode & FMODE_TEXTMODE) && (fmode & FMODE_BINMODE)) {
-	fptr->mode &= ~FMODE_TEXTMODE;
-	setmode(fptr->fd, O_BINARY);
+        fptr->mode &= ~FMODE_TEXTMODE;
+        setmode(fptr->fd, O_BINARY);
     }
 #if RUBY_CRLF_ENVIRONMENT
     if (fptr->encs.ecflags & ECONV_DEFAULT_NEWLINE_DECORATOR) {
-	fptr->encs.ecflags |= ECONV_UNIVERSAL_NEWLINE_DECORATOR;
+        fptr->encs.ecflags |= ECONV_UNIVERSAL_NEWLINE_DECORATOR;
     }
 #endif
 #endif
     fptr->mode |= fmode;
 #if DEFAULT_TEXTMODE
     if ((fptr2->mode & FMODE_TEXTMODE) && (fmode & FMODE_BINMODE)) {
-	fptr2->mode &= ~FMODE_TEXTMODE;
-	setmode(fptr2->fd, O_BINARY);
+        fptr2->mode &= ~FMODE_TEXTMODE;
+        setmode(fptr2->fd, O_BINARY);
     }
 #endif
     fptr2->mode |= fmode;
 
     ret = rb_assoc_new(r, w);
     if (rb_block_given_p()) {
-	VALUE rw[2];
-	rw[0] = r;
-	rw[1] = w;
-	return rb_ensure(rb_yield, ret, pipe_pair_close, (VALUE)rw);
+        VALUE rw[2];
+        rw[0] = r;
+        rw[1] = w;
+        return rb_ensure(rb_yield, ret, pipe_pair_close, (VALUE)rw);
     }
     return ret;
 }
@@ -11250,15 +11856,15 @@ open_key_args(VALUE klass, int argc, VALUE *argv, VALUE opt, struct foreach_arg
     arg->argc = argc;
     arg->argv = argv;
     if (NIL_P(opt)) {
-	vmode = INT2NUM(O_RDONLY);
-	vperm = INT2FIX(0666);
+        vmode = INT2NUM(O_RDONLY);
+        vperm = INT2FIX(0666);
     }
     else if (!NIL_P(v = rb_hash_aref(opt, sym_open_args))) {
-	int n;
+        int n;
 
-	v = rb_to_array_type(v);
-	n = RARRAY_LENINT(v);
-	rb_check_arity(n, 0, 3); /* rb_io_open */
+        v = rb_to_array_type(v);
+        n = RARRAY_LENINT(v);
+        rb_check_arity(n, 0, 3); /* rb_io_open */
         rb_scan_args_kw(RB_SCAN_ARGS_LAST_HASH_KEYWORDS, n, RARRAY_CONST_PTR(v), "02:", &vmode, &vperm, &opt);
     }
     arg->io = rb_io_open(klass, path, vmode, vperm, opt);
@@ -11270,9 +11876,11 @@ io_s_foreach(VALUE v)
     struct getline_arg *arg = (void *)v;
     VALUE str;
 
+    if (arg->limit == 0)
+        rb_raise(rb_eArgError, "invalid limit: 0 for foreach");
     while (!NIL_P(str = rb_io_getline_1(arg->rs, arg->limit, arg->chomp, arg->io))) {
-	rb_lastline_set(str);
-	rb_yield(str);
+        rb_lastline_set(str);
+        rb_yield(str);
     }
     rb_lastline_set(Qnil);
     return Qnil;
@@ -11378,7 +11986,7 @@ rb_io_s_foreach(int argc, VALUE *argv, VALUE self)
     struct foreach_arg arg;
     struct getline_arg garg;
 
-    argc = rb_scan_args(argc, argv, "13:", NULL, NULL, NULL, NULL, &opt);
+    argc = rb_scan_args(argc, argv, "12:", NULL, NULL, NULL, &opt);
     RETURN_ENUMERATOR(self, orig_argc, argv);
     extract_getline_args(argc-1, argv+1, &garg);
     open_key_args(self, argc, argv, opt, &arg);
@@ -11473,7 +12081,7 @@ rb_io_s_readlines(int argc, VALUE *argv, VALUE io)
     struct foreach_arg arg;
     struct getline_arg garg;
 
-    argc = rb_scan_args(argc, argv, "13:", NULL, NULL, NULL, NULL, &opt);
+    argc = rb_scan_args(argc, argv, "12:", NULL, NULL, NULL, &opt);
     extract_getline_args(argc-1, argv+1, &garg);
     open_key_args(io, argc, argv, opt, &arg);
     if (NIL_P(arg.io)) return Qnil;
@@ -11528,12 +12136,16 @@ seek_before_access(VALUE argp)
  *    IO.read('| cat t.txt')
  *    # => "First line\nSecond line\n\nThird line\nFourth line\n"
  *
- *  With only argument +path+ given, reads and returns the entire content
+ *  With only argument +path+ given, reads in text mode and returns the entire content
  *  of the file at the given path:
  *
  *    IO.read('t.txt')
  *    # => "First line\nSecond line\n\nThird line\nFourth line\n"
  *
+ *  On Windows, text mode can terminate reading and leave bytes in the file
+ *  unread when encountering certain special bytes. Consider using
+ *  IO.binread if all bytes in the file should be read.
+ *
  *  For both forms, command and path, the remaining arguments are the same.
  *
  *  With argument +length+, returns +length+ bytes if available:
@@ -11565,17 +12177,17 @@ rb_io_s_read(int argc, VALUE *argv, VALUE io)
     open_key_args(io, argc, argv, opt, &arg);
     if (NIL_P(arg.io)) return Qnil;
     if (!NIL_P(offset)) {
-	struct seek_arg sarg;
-	int state = 0;
-	sarg.io = arg.io;
-	sarg.offset = offset;
-	sarg.mode = SEEK_SET;
-	rb_protect(seek_before_access, (VALUE)&sarg, &state);
-	if (state) {
-	    rb_io_close(arg.io);
-	    rb_jump_tag(state);
-	}
-	if (arg.argc == 2) arg.argc = 1;
+        struct seek_arg sarg;
+        int state = 0;
+        sarg.io = arg.io;
+        sarg.offset = offset;
+        sarg.mode = SEEK_SET;
+        rb_protect(seek_before_access, (VALUE)&sarg, &state);
+        if (state) {
+            rb_io_close(arg.io);
+            rb_jump_tag(state);
+        }
+        if (arg.argc == 2) arg.argc = 1;
     }
     return rb_ensure(io_s_read, (VALUE)&arg, rb_io_close, arg.io);
 }
@@ -11600,10 +12212,10 @@ rb_io_s_binread(int argc, VALUE *argv, VALUE io)
     VALUE offset;
     struct foreach_arg arg;
     enum {
-	fmode = FMODE_READABLE|FMODE_BINMODE,
-	oflags = O_RDONLY
+        fmode = FMODE_READABLE|FMODE_BINMODE,
+        oflags = O_RDONLY
 #ifdef O_BINARY
-		|O_BINARY
+                |O_BINARY
 #endif
     };
     convconfig_t convconfig = {NULL, NULL, 0, Qnil};
@@ -11616,16 +12228,16 @@ rb_io_s_binread(int argc, VALUE *argv, VALUE io)
     arg.argv = argv+1;
     arg.argc = (argc > 1) ? 1 : 0;
     if (!NIL_P(offset)) {
-	struct seek_arg sarg;
-	int state = 0;
-	sarg.io = arg.io;
-	sarg.offset = offset;
-	sarg.mode = SEEK_SET;
-	rb_protect(seek_before_access, (VALUE)&sarg, &state);
-	if (state) {
-	    rb_io_close(arg.io);
-	    rb_jump_tag(state);
-	}
+        struct seek_arg sarg;
+        int state = 0;
+        sarg.io = arg.io;
+        sarg.offset = offset;
+        sarg.mode = SEEK_SET;
+        rb_protect(seek_before_access, (VALUE)&sarg, &state);
+        if (state) {
+            rb_io_close(arg.io);
+            rb_jump_tag(state);
+        }
     }
     return rb_ensure(io_s_read, (VALUE)&arg, rb_io_close, arg.io);
 }
@@ -11775,15 +12387,15 @@ rb_io_s_binwrite(int argc, VALUE *argv, VALUE io)
 struct copy_stream_struct {
     VALUE src;
     VALUE dst;
-    off_t copy_length; /* (off_t)-1 if not specified */
-    off_t src_offset; /* (off_t)-1 if not specified */
+    rb_off_t copy_length; /* (rb_off_t)-1 if not specified */
+    rb_off_t src_offset; /* (rb_off_t)-1 if not specified */
 
     rb_io_t *src_fptr;
     rb_io_t *dst_fptr;
     unsigned close_src : 1;
     unsigned close_dst : 1;
     int error_no;
-    off_t total;
+    rb_off_t total;
     const char *syserr;
     const char *notimp;
     VALUE th;
@@ -11815,18 +12427,18 @@ maygvl_copy_stream_continue_p(int has_gvl, struct copy_stream_struct *stp)
 #if defined(ERESTART)
       case ERESTART:
 #endif
-	if (rb_thread_interrupted(stp->th)) {
+        if (rb_thread_interrupted(stp->th)) {
             if (has_gvl)
                 rb_thread_execute_interrupts(stp->th);
             else
                 rb_thread_call_with_gvl(exec_interrupts, (void *)stp->th);
         }
-	return TRUE;
+        return TRUE;
     }
     return FALSE;
 }
 
-struct wait_for_single_fd {
+struct fiber_scheduler_wait_for_arguments {
     VALUE scheduler;
 
     rb_io_t *fptr;
@@ -11836,11 +12448,11 @@ struct wait_for_single_fd {
 };
 
 static void *
-rb_thread_fiber_scheduler_wait_for(void * _args)
+fiber_scheduler_wait_for(void * _arguments)
 {
-    struct wait_for_single_fd *args = (struct wait_for_single_fd *)_args;
+    struct fiber_scheduler_wait_for_arguments *arguments = (struct fiber_scheduler_wait_for_arguments *)_arguments;
 
-    args->result = rb_fiber_scheduler_io_wait(args->scheduler, args->fptr->self, INT2NUM(args->events), Qnil);
+    arguments->result = rb_fiber_scheduler_io_wait(arguments->scheduler, arguments->fptr->self, INT2NUM(arguments->events), RUBY_IO_TIMEOUT_DEFAULT);
 
     return NULL;
 }
@@ -11850,12 +12462,12 @@ rb_thread_fiber_scheduler_wait_for(void * _args)
 STATIC_ASSERT(pollin_expected, POLLIN == RB_WAITFD_IN);
 STATIC_ASSERT(pollout_expected, POLLOUT == RB_WAITFD_OUT);
 static int
-nogvl_wait_for(VALUE th, rb_io_t *fptr, short events)
+nogvl_wait_for(VALUE th, rb_io_t *fptr, short events, struct timeval *timeout)
 {
     VALUE scheduler = rb_fiber_scheduler_current_for_thread(th);
     if (scheduler != Qnil) {
-        struct wait_for_single_fd args = {.scheduler = scheduler, .fptr = fptr, .events = events};
-        rb_thread_call_with_gvl(rb_thread_fiber_scheduler_wait_for, &args);
+        struct fiber_scheduler_wait_for_arguments args = {.scheduler = scheduler, .fptr = fptr, .events = events};
+        rb_thread_call_with_gvl(fiber_scheduler_wait_for, &args);
         return RTEST(args.result);
     }
 
@@ -11867,22 +12479,32 @@ nogvl_wait_for(VALUE th, rb_io_t *fptr, short events)
     fds.fd = fd;
     fds.events = events;
 
-    return poll(&fds, 1, -1);
+    int timeout_milliseconds = -1;
+
+    if (timeout) {
+        timeout_milliseconds = (int)(timeout->tv_sec * 1000) + (int)(timeout->tv_usec / 1000);
+    }
+
+    return poll(&fds, 1, timeout_milliseconds);
 }
 #else /* !USE_POLL */
 #  define IOWAIT_SYSCALL "select"
 static int
-nogvl_wait_for(VALUE th, rb_io_t *fptr, short events)
+nogvl_wait_for(VALUE th, rb_io_t *fptr, short events, struct timeval *timeout)
 {
     VALUE scheduler = rb_fiber_scheduler_current_for_thread(th);
     if (scheduler != Qnil) {
-        struct wait_for_single_fd args = {.scheduler = scheduler, .fptr = fptr, .events = events};
-        rb_thread_call_with_gvl(rb_thread_fiber_scheduler_wait_for, &args);
+        struct fiber_scheduler_wait_for_arguments args = {.scheduler = scheduler, .fptr = fptr, .events = events};
+        rb_thread_call_with_gvl(fiber_scheduler_wait_for, &args);
         return RTEST(args.result);
     }
 
     int fd = fptr->fd;
-    if (fd == -1) return 0;
+
+    if (fd == -1) {
+        errno = EBADF;
+        return -1;
+    }
 
     rb_fdset_t fds;
     int ret;
@@ -11892,16 +12514,18 @@ nogvl_wait_for(VALUE th, rb_io_t *fptr, short events)
 
     switch (events) {
       case RB_WAITFD_IN:
-        ret = rb_fd_select(fd + 1, &fds, 0, 0, 0);
+        ret = rb_fd_select(fd + 1, &fds, 0, 0, timeout);
         break;
       case RB_WAITFD_OUT:
-        ret = rb_fd_select(fd + 1, 0, &fds, 0, 0);
+        ret = rb_fd_select(fd + 1, 0, &fds, 0, timeout);
         break;
       default:
         VM_UNREACHABLE(nogvl_wait_for);
     }
 
     rb_fd_term(&fds);
+
+    // On timeout, this returns 0.
     return ret;
 }
 #endif /* !USE_POLL */
@@ -11916,7 +12540,7 @@ maygvl_copy_stream_wait_read(int has_gvl, struct copy_stream_struct *stp)
             ret = RB_NUM2INT(rb_io_wait(stp->src, RB_INT2NUM(RUBY_IO_READABLE), Qnil));
         }
         else {
-            ret = nogvl_wait_for(stp->th, stp->src_fptr, RB_WAITFD_IN);
+            ret = nogvl_wait_for(stp->th, stp->src_fptr, RB_WAITFD_IN, NULL);
         }
     } while (ret < 0 && maygvl_copy_stream_continue_p(has_gvl, stp));
 
@@ -11934,7 +12558,7 @@ nogvl_copy_stream_wait_write(struct copy_stream_struct *stp)
     int ret;
 
     do {
-	ret = nogvl_wait_for(stp->th, stp->dst_fptr, RB_WAITFD_OUT);
+        ret = nogvl_wait_for(stp->th, stp->dst_fptr, RB_WAITFD_OUT, NULL);
     } while (ret < 0 && maygvl_copy_stream_continue_p(0, stp));
 
     if (ret < 0) {
@@ -11948,7 +12572,7 @@ nogvl_copy_stream_wait_write(struct copy_stream_struct *stp)
 #ifdef USE_COPY_FILE_RANGE
 
 static ssize_t
-simple_copy_file_range(int in_fd, off_t *in_offset, int out_fd, off_t *out_offset, size_t count, unsigned int flags)
+simple_copy_file_range(int in_fd, rb_off_t *in_offset, int out_fd, rb_off_t *out_offset, size_t count, unsigned int flags)
 {
 #ifdef HAVE_COPY_FILE_RANGE
     return copy_file_range(in_fd, in_offset, out_fd, out_offset, count, flags);
@@ -11961,43 +12585,43 @@ static int
 nogvl_copy_file_range(struct copy_stream_struct *stp)
 {
     ssize_t ss;
-    off_t src_size;
-    off_t copy_length, src_offset, *src_offset_ptr;
+    rb_off_t src_size;
+    rb_off_t copy_length, src_offset, *src_offset_ptr;
 
     if (!S_ISREG(stp->src_stat.st_mode))
         return 0;
 
     src_size = stp->src_stat.st_size;
     src_offset = stp->src_offset;
-    if (src_offset >= (off_t)0) {
-	src_offset_ptr = &src_offset;
+    if (src_offset >= (rb_off_t)0) {
+        src_offset_ptr = &src_offset;
     }
     else {
-	src_offset_ptr = NULL; /* if src_offset_ptr is NULL, then bytes are read from in_fd starting from the file offset */
+        src_offset_ptr = NULL; /* if src_offset_ptr is NULL, then bytes are read from in_fd starting from the file offset */
     }
 
     copy_length = stp->copy_length;
-    if (copy_length < (off_t)0) {
-        if (src_offset < (off_t)0) {
-	    off_t current_offset;
+    if (copy_length < (rb_off_t)0) {
+        if (src_offset < (rb_off_t)0) {
+            rb_off_t current_offset;
             errno = 0;
             current_offset = lseek(stp->src_fptr->fd, 0, SEEK_CUR);
-            if (current_offset < (off_t)0 && errno) {
+            if (current_offset < (rb_off_t)0 && errno) {
                 stp->syserr = "lseek";
                 stp->error_no = errno;
                 return (int)current_offset;
             }
             copy_length = src_size - current_offset;
-	}
-	else {
+        }
+        else {
             copy_length = src_size - src_offset;
-	}
+        }
     }
 
   retry_copy_file_range:
 # if SIZEOF_OFF_T > SIZEOF_SIZE_T
     /* we are limited by the 32-bit ssize_t return value on 32-bit */
-    ss = (copy_length > (off_t)SSIZE_MAX) ? SSIZE_MAX : (ssize_t)copy_length;
+    ss = (copy_length > (rb_off_t)SSIZE_MAX) ? SSIZE_MAX : (ssize_t)copy_length;
 # else
     ss = (ssize_t)copy_length;
 # endif
@@ -12010,39 +12634,39 @@ nogvl_copy_file_range(struct copy_stream_struct *stp)
         }
     }
     if (ss < 0) {
-	if (maygvl_copy_stream_continue_p(0, stp)) {
+        if (maygvl_copy_stream_continue_p(0, stp)) {
             goto retry_copy_file_range;
-	}
+        }
         switch (errno) {
-	  case EINVAL:
-	  case EPERM: /* copy_file_range(2) doesn't exist (may happen in
-			 docker container) */
+          case EINVAL:
+          case EPERM: /* copy_file_range(2) doesn't exist (may happen in
+                         docker container) */
 #ifdef ENOSYS
-	  case ENOSYS:
+          case ENOSYS:
 #endif
 #ifdef EXDEV
-	  case EXDEV: /* in_fd and out_fd are not on the same filesystem */
+          case EXDEV: /* in_fd and out_fd are not on the same filesystem */
 #endif
             return 0;
-	  case EAGAIN:
+          case EAGAIN:
 #if EWOULDBLOCK != EAGAIN
-	  case EWOULDBLOCK:
+          case EWOULDBLOCK:
 #endif
             {
                 int ret = nogvl_copy_stream_wait_write(stp);
                 if (ret < 0) return ret;
             }
             goto retry_copy_file_range;
-	  case EBADF:
-	    {
-		int e = errno;
-		int flags = fcntl(stp->dst_fptr->fd, F_GETFL);
+          case EBADF:
+            {
+                int e = errno;
+                int flags = fcntl(stp->dst_fptr->fd, F_GETFL);
 
-		if (flags != -1 && flags & O_APPEND) {
-		    return 0;
-		}
-		errno = e;
-	    }
+                if (flags != -1 && flags & O_APPEND) {
+                    return 0;
+                }
+                errno = e;
+            }
         }
         stp->syserr = "copy_file_range";
         stp->error_no = errno;
@@ -12056,11 +12680,11 @@ nogvl_copy_file_range(struct copy_stream_struct *stp)
 static int
 nogvl_fcopyfile(struct copy_stream_struct *stp)
 {
-    off_t cur, ss = 0;
-    const off_t src_offset = stp->src_offset;
+    rb_off_t cur, ss = 0;
+    const rb_off_t src_offset = stp->src_offset;
     int ret;
 
-    if (stp->copy_length >= (off_t)0) {
+    if (stp->copy_length >= (rb_off_t)0) {
         /* copy_length can't be specified in fcopyfile(3) */
         return 0;
     }
@@ -12070,30 +12694,30 @@ nogvl_fcopyfile(struct copy_stream_struct *stp)
 
     if (!S_ISREG(stp->dst_stat.st_mode))
         return 0;
-    if (lseek(stp->dst_fptr->fd, 0, SEEK_CUR) > (off_t)0) /* if dst IO was already written */
+    if (lseek(stp->dst_fptr->fd, 0, SEEK_CUR) > (rb_off_t)0) /* if dst IO was already written */
         return 0;
     if (fcntl(stp->dst_fptr->fd, F_GETFL) & O_APPEND) {
         /* fcopyfile(3) appends src IO to dst IO and then truncates
          * dst IO to src IO's original size. */
-        off_t end = lseek(stp->dst_fptr->fd, 0, SEEK_END);
+        rb_off_t end = lseek(stp->dst_fptr->fd, 0, SEEK_END);
         lseek(stp->dst_fptr->fd, 0, SEEK_SET);
-        if (end > (off_t)0) return 0;
+        if (end > (rb_off_t)0) return 0;
     }
 
-    if (src_offset > (off_t)0) {
-        off_t r;
+    if (src_offset > (rb_off_t)0) {
+        rb_off_t r;
 
         /* get current offset */
         errno = 0;
         cur = lseek(stp->src_fptr->fd, 0, SEEK_CUR);
-        if (cur < (off_t)0 && errno) {
+        if (cur < (rb_off_t)0 && errno) {
             stp->error_no = errno;
             return 1;
         }
 
         errno = 0;
         r = lseek(stp->src_fptr->fd, src_offset, SEEK_SET);
-        if (r < (off_t)0 && errno) {
+        if (r < (rb_off_t)0 && errno) {
             stp->error_no = errno;
             return 1;
         }
@@ -12105,12 +12729,12 @@ nogvl_fcopyfile(struct copy_stream_struct *stp)
 
     if (ret == 0) { /* success */
         stp->total = ss;
-        if (src_offset > (off_t)0) {
-            off_t r;
+        if (src_offset > (rb_off_t)0) {
+            rb_off_t r;
             errno = 0;
             /* reset offset */
             r = lseek(stp->src_fptr->fd, cur, SEEK_SET);
-            if (r < (off_t)0 && errno) {
+            if (r < (rb_off_t)0 && errno) {
                 stp->error_no = errno;
                 return 1;
             }
@@ -12141,7 +12765,7 @@ nogvl_fcopyfile(struct copy_stream_struct *stp)
 #  endif
 
 static ssize_t
-simple_sendfile(int out_fd, int in_fd, off_t *offset, off_t count)
+simple_sendfile(int out_fd, int in_fd, rb_off_t *offset, rb_off_t count)
 {
     return sendfile(out_fd, in_fd, offset, (size_t)count);
 }
@@ -12153,11 +12777,11 @@ simple_sendfile(int out_fd, int in_fd, off_t *offset, off_t count)
 #  define USE_SENDFILE
 
 static ssize_t
-simple_sendfile(int out_fd, int in_fd, off_t *offset, off_t count)
+simple_sendfile(int out_fd, int in_fd, rb_off_t *offset, rb_off_t count)
 {
     int r;
-    off_t pos = offset ? *offset : lseek(in_fd, 0, SEEK_CUR);
-    off_t sbytes;
+    rb_off_t pos = offset ? *offset : lseek(in_fd, 0, SEEK_CUR);
+    rb_off_t sbytes;
 #  ifdef __APPLE__
     r = sendfile(in_fd, out_fd, pos, &count, NULL, 0);
     sbytes = count;
@@ -12166,10 +12790,10 @@ simple_sendfile(int out_fd, int in_fd, off_t *offset, off_t count)
 #  endif
     if (r != 0 && sbytes == 0) return r;
     if (offset) {
-	*offset += sbytes;
+        *offset += sbytes;
     }
     else {
-	lseek(in_fd, sbytes, SEEK_CUR);
+        lseek(in_fd, sbytes, SEEK_CUR);
     }
     return (ssize_t)sbytes;
 }
@@ -12183,9 +12807,9 @@ static int
 nogvl_copy_stream_sendfile(struct copy_stream_struct *stp)
 {
     ssize_t ss;
-    off_t src_size;
-    off_t copy_length;
-    off_t src_offset;
+    rb_off_t src_size;
+    rb_off_t copy_length;
+    rb_off_t src_offset;
     int use_pread;
 
     if (!S_ISREG(stp->src_stat.st_mode))
@@ -12194,21 +12818,21 @@ nogvl_copy_stream_sendfile(struct copy_stream_struct *stp)
     src_size = stp->src_stat.st_size;
 #ifndef __linux__
     if ((stp->dst_stat.st_mode & S_IFMT) != S_IFSOCK)
-	return 0;
+        return 0;
 #endif
 
     src_offset = stp->src_offset;
-    use_pread = src_offset >= (off_t)0;
+    use_pread = src_offset >= (rb_off_t)0;
 
     copy_length = stp->copy_length;
-    if (copy_length < (off_t)0) {
+    if (copy_length < (rb_off_t)0) {
         if (use_pread)
             copy_length = src_size - src_offset;
         else {
-            off_t cur;
+            rb_off_t cur;
             errno = 0;
             cur = lseek(stp->src_fptr->fd, 0, SEEK_CUR);
-            if (cur < (off_t)0 && errno) {
+            if (cur < (rb_off_t)0 && errno) {
                 stp->syserr = "lseek";
                 stp->error_no = errno;
                 return (int)cur;
@@ -12220,7 +12844,7 @@ nogvl_copy_stream_sendfile(struct copy_stream_struct *stp)
   retry_sendfile:
 # if SIZEOF_OFF_T > SIZEOF_SIZE_T
     /* we are limited by the 32-bit ssize_t return value on 32-bit */
-    ss = (copy_length > (off_t)SSIZE_MAX) ? SSIZE_MAX : (ssize_t)copy_length;
+    ss = (copy_length > (rb_off_t)SSIZE_MAX) ? SSIZE_MAX : (ssize_t)copy_length;
 # else
     ss = (ssize_t)copy_length;
 # endif
@@ -12238,22 +12862,22 @@ nogvl_copy_stream_sendfile(struct copy_stream_struct *stp)
         }
     }
     if (ss < 0) {
-	if (maygvl_copy_stream_continue_p(0, stp))
-	    goto retry_sendfile;
+        if (maygvl_copy_stream_continue_p(0, stp))
+            goto retry_sendfile;
         switch (errno) {
-	  case EINVAL:
+          case EINVAL:
 #ifdef ENOSYS
-	  case ENOSYS:
+          case ENOSYS:
 #endif
 #ifdef EOPNOTSUP
-	  /* some RedHat kernels may return EOPNOTSUP on an NFS mount.
-	     see also: [Feature #16965] */
-	  case EOPNOTSUP:
+          /* some RedHat kernels may return EOPNOTSUP on an NFS mount.
+             see also: [Feature #16965] */
+          case EOPNOTSUP:
 #endif
             return 0;
-	  case EAGAIN:
+          case EAGAIN:
 #if EWOULDBLOCK != EAGAIN
-	  case EWOULDBLOCK:
+          case EWOULDBLOCK:
 #endif
             {
                 int ret;
@@ -12285,17 +12909,17 @@ static ssize_t
 maygvl_read(int has_gvl, rb_io_t *fptr, void *buf, size_t count)
 {
     if (has_gvl)
-        return rb_read_internal(fptr, buf, count);
+        return rb_io_read_memory(fptr, buf, count);
     else
         return read(fptr->fd, buf, count);
 }
 
 static ssize_t
-maygvl_copy_stream_read(int has_gvl, struct copy_stream_struct *stp, char *buf, size_t len, off_t offset)
+maygvl_copy_stream_read(int has_gvl, struct copy_stream_struct *stp, char *buf, size_t len, rb_off_t offset)
 {
     ssize_t ss;
   retry_read:
-    if (offset < (off_t)0) {
+    if (offset < (rb_off_t)0) {
         ss = maygvl_read(has_gvl, stp->src_fptr, buf, len);
     }
     else {
@@ -12310,12 +12934,12 @@ maygvl_copy_stream_read(int has_gvl, struct copy_stream_struct *stp, char *buf,
         return 0;
     }
     if (ss < 0) {
-	if (maygvl_copy_stream_continue_p(has_gvl, stp))
-	    goto retry_read;
+        if (maygvl_copy_stream_continue_p(has_gvl, stp))
+            goto retry_read;
         switch (errno) {
-	  case EAGAIN:
+          case EAGAIN:
 #if EWOULDBLOCK != EAGAIN
-	  case EWOULDBLOCK:
+          case EWOULDBLOCK:
 #endif
             {
                 int ret = maygvl_copy_stream_wait_read(has_gvl, stp);
@@ -12323,12 +12947,12 @@ maygvl_copy_stream_read(int has_gvl, struct copy_stream_struct *stp, char *buf,
             }
             goto retry_read;
 #ifdef ENOSYS
-	  case ENOSYS:
+          case ENOSYS:
             stp->notimp = "pread";
             return ss;
 #endif
         }
-        stp->syserr = offset < (off_t)0 ?  "read" : "pread";
+        stp->syserr = offset < (rb_off_t)0 ?  "read" : "pread";
         stp->error_no = errno;
     }
     return ss;
@@ -12367,31 +12991,31 @@ nogvl_copy_stream_read_write(struct copy_stream_struct *stp)
     size_t len;
     ssize_t ss;
     int ret;
-    off_t copy_length;
+    rb_off_t copy_length;
+    rb_off_t src_offset;
     int use_eof;
-    off_t src_offset;
     int use_pread;
 
     copy_length = stp->copy_length;
-    use_eof = copy_length < (off_t)0;
+    use_eof = copy_length < (rb_off_t)0;
     src_offset = stp->src_offset;
-    use_pread = src_offset >= (off_t)0;
+    use_pread = src_offset >= (rb_off_t)0;
 
     if (use_pread && stp->close_src) {
-        off_t r;
-	errno = 0;
+        rb_off_t r;
+        errno = 0;
         r = lseek(stp->src_fptr->fd, src_offset, SEEK_SET);
-        if (r < (off_t)0 && errno) {
+        if (r < (rb_off_t)0 && errno) {
             stp->syserr = "lseek";
             stp->error_no = errno;
             return;
         }
-        src_offset = (off_t)-1;
+        src_offset = (rb_off_t)-1;
         use_pread = 0;
     }
 
     while (use_eof || 0 < copy_length) {
-        if (!use_eof && copy_length < (off_t)sizeof(buf)) {
+        if (!use_eof && copy_length < (rb_off_t)sizeof(buf)) {
             len = (size_t)copy_length;
         }
         else {
@@ -12403,7 +13027,7 @@ nogvl_copy_stream_read_write(struct copy_stream_struct *stp)
                 src_offset += ss;
         }
         else {
-            ss = maygvl_copy_stream_read(0, stp, buf, len, (off_t)-1);
+            ss = maygvl_copy_stream_read(0, stp, buf, len, (rb_off_t)-1);
         }
         if (ss <= 0) /* EOF or error */
             return;
@@ -12428,7 +13052,7 @@ nogvl_copy_stream_func(void *arg)
 #ifdef USE_COPY_FILE_RANGE
     ret = nogvl_copy_file_range(stp);
     if (ret != 0)
-	goto finish; /* error or success */
+        goto finish; /* error or success */
 #endif
 
 #ifdef HAVE_FCOPYFILE
@@ -12458,27 +13082,28 @@ copy_stream_fallback_body(VALUE arg)
     const int buflen = 16*1024;
     VALUE n;
     VALUE buf = rb_str_buf_new(buflen);
-    off_t rest = stp->copy_length;
-    off_t off = stp->src_offset;
+    rb_off_t rest = stp->copy_length;
+    rb_off_t off = stp->src_offset;
     ID read_method = id_readpartial;
 
     if (!stp->src_fptr) {
-	if (!rb_respond_to(stp->src, read_method)) {
-	    read_method = id_read;
-	}
+        if (!rb_respond_to(stp->src, read_method)) {
+            read_method = id_read;
+        }
     }
 
     while (1) {
         long numwrote;
         long l;
-        if (stp->copy_length < (off_t)0) {
+        rb_str_make_independent(buf);
+        if (stp->copy_length < (rb_off_t)0) {
             l = buflen;
         }
         else {
-	    if (rest == 0) {
-		rb_str_resize(buf, 0);
-		break;
-	    }
+            if (rest == 0) {
+                rb_str_resize(buf, 0);
+                break;
+            }
             l = buflen < rest ? buflen : (long)rest;
         }
         if (!stp->src_fptr) {
@@ -12496,16 +13121,16 @@ copy_stream_fallback_body(VALUE arg)
                 return Qnil;
             if (ss == 0)
                 rb_eof_error();
-            if (off >= (off_t)0)
+            if (off >= (rb_off_t)0)
                 off += ss;
         }
         n = rb_io_write(stp->dst, buf);
         numwrote = NUM2LONG(n);
         stp->total += numwrote;
         rest -= numwrote;
-	if (read_method == id_read && RSTRING_LEN(buf) == 0) {
-	    break;
-	}
+        if (read_method == id_read && RSTRING_LEN(buf) == 0) {
+            break;
+        }
     }
 
     return Qnil;
@@ -12514,8 +13139,8 @@ copy_stream_fallback_body(VALUE arg)
 static VALUE
 copy_stream_fallback(struct copy_stream_struct *stp)
 {
-    if (!stp->src_fptr && stp->src_offset >= (off_t)0) {
-	rb_raise(rb_eArgError, "cannot specify src_offset for non-IO");
+    if (!stp->src_fptr && stp->src_offset >= (rb_off_t)0) {
+        rb_raise(rb_eArgError, "cannot specify src_offset for non-IO");
     }
     rb_rescue2(copy_stream_fallback_body, (VALUE)stp,
                (VALUE (*) (VALUE, VALUE))0, (VALUE)0,
@@ -12530,37 +13155,37 @@ copy_stream_body(VALUE arg)
     VALUE src_io = stp->src, dst_io = stp->dst;
     const int common_oflags = 0
 #ifdef O_NOCTTY
-	| O_NOCTTY
+        | O_NOCTTY
 #endif
-	;
+        ;
 
     stp->th = rb_thread_current();
 
     stp->total = 0;
 
     if (src_io == argf ||
-	!(RB_TYPE_P(src_io, T_FILE) ||
-	  RB_TYPE_P(src_io, T_STRING) ||
-	  rb_respond_to(src_io, rb_intern("to_path")))) {
+        !(RB_TYPE_P(src_io, T_FILE) ||
+          RB_TYPE_P(src_io, T_STRING) ||
+          rb_respond_to(src_io, rb_intern("to_path")))) {
         stp->src_fptr = NULL;
     }
     else {
         int stat_ret;
-	VALUE tmp_io = rb_io_check_io(src_io);
-	if (!NIL_P(tmp_io)) {
-	    src_io = tmp_io;
-	}
-	else if (!RB_TYPE_P(src_io, T_FILE)) {
-	    VALUE args[2];
-	    FilePathValue(src_io);
-	    args[0] = src_io;
-	    args[1] = INT2NUM(O_RDONLY|common_oflags);
-	    src_io = rb_class_new_instance(2, args, rb_cFile);
-	    stp->src = src_io;
-	    stp->close_src = 1;
-	}
-	RB_IO_POINTER(src_io, stp->src_fptr);
-	rb_io_check_byte_readable(stp->src_fptr);
+        VALUE tmp_io = rb_io_check_io(src_io);
+        if (!NIL_P(tmp_io)) {
+            src_io = tmp_io;
+        }
+        else if (!RB_TYPE_P(src_io, T_FILE)) {
+            VALUE args[2];
+            FilePathValue(src_io);
+            args[0] = src_io;
+            args[1] = INT2NUM(O_RDONLY|common_oflags);
+            src_io = rb_class_new_instance(2, args, rb_cFile);
+            stp->src = src_io;
+            stp->close_src = 1;
+        }
+        RB_IO_POINTER(src_io, stp->src_fptr);
+        rb_io_check_byte_readable(stp->src_fptr);
 
         stat_ret = fstat(stp->src_fptr->fd, &stp->src_stat);
         if (stat_ret < 0) {
@@ -12571,33 +13196,33 @@ copy_stream_body(VALUE arg)
     }
 
     if (dst_io == argf ||
-	!(RB_TYPE_P(dst_io, T_FILE) ||
-	  RB_TYPE_P(dst_io, T_STRING) ||
-	  rb_respond_to(dst_io, rb_intern("to_path")))) {
-	stp->dst_fptr = NULL;
+        !(RB_TYPE_P(dst_io, T_FILE) ||
+          RB_TYPE_P(dst_io, T_STRING) ||
+          rb_respond_to(dst_io, rb_intern("to_path")))) {
+        stp->dst_fptr = NULL;
     }
     else {
         int stat_ret;
         VALUE tmp_io = rb_io_check_io(dst_io);
-	if (!NIL_P(tmp_io)) {
-	    dst_io = GetWriteIO(tmp_io);
-	}
-	else if (!RB_TYPE_P(dst_io, T_FILE)) {
-	    VALUE args[3];
-	    FilePathValue(dst_io);
-	    args[0] = dst_io;
-	    args[1] = INT2NUM(O_WRONLY|O_CREAT|O_TRUNC|common_oflags);
-	    args[2] = INT2FIX(0666);
-	    dst_io = rb_class_new_instance(3, args, rb_cFile);
-	    stp->dst = dst_io;
-	    stp->close_dst = 1;
-	}
-	else {
-	    dst_io = GetWriteIO(dst_io);
-	    stp->dst = dst_io;
-	}
-	RB_IO_POINTER(dst_io, stp->dst_fptr);
-	rb_io_check_writable(stp->dst_fptr);
+        if (!NIL_P(tmp_io)) {
+            dst_io = GetWriteIO(tmp_io);
+        }
+        else if (!RB_TYPE_P(dst_io, T_FILE)) {
+            VALUE args[3];
+            FilePathValue(dst_io);
+            args[0] = dst_io;
+            args[1] = INT2NUM(O_WRONLY|O_CREAT|O_TRUNC|common_oflags);
+            args[2] = INT2FIX(0666);
+            dst_io = rb_class_new_instance(3, args, rb_cFile);
+            stp->dst = dst_io;
+            stp->close_dst = 1;
+        }
+        else {
+            dst_io = GetWriteIO(dst_io);
+            stp->dst = dst_io;
+        }
+        RB_IO_POINTER(dst_io, stp->dst_fptr);
+        rb_io_check_writable(stp->dst_fptr);
 
         stat_ret = fstat(stp->dst_fptr->fd, &stp->dst_stat);
         if (stat_ret < 0) {
@@ -12609,15 +13234,15 @@ copy_stream_body(VALUE arg)
 
 #ifdef O_BINARY
     if (stp->src_fptr)
-	SET_BINARY_MODE_WITH_SEEK_CUR(stp->src_fptr);
+        SET_BINARY_MODE_WITH_SEEK_CUR(stp->src_fptr);
 #endif
     if (stp->dst_fptr)
-	io_ascii8bit_binmode(stp->dst_fptr);
+        io_ascii8bit_binmode(stp->dst_fptr);
 
-    if (stp->src_offset < (off_t)0 && stp->src_fptr && stp->src_fptr->rbuf.len) {
+    if (stp->src_offset < (rb_off_t)0 && stp->src_fptr && stp->src_fptr->rbuf.len) {
         size_t len = stp->src_fptr->rbuf.len;
         VALUE str;
-        if (stp->copy_length >= (off_t)0 && stp->copy_length < (off_t)len) {
+        if (stp->copy_length >= (rb_off_t)0 && stp->copy_length < (rb_off_t)len) {
             len = (size_t)stp->copy_length;
         }
         str = rb_str_buf_new(len);
@@ -12628,15 +13253,15 @@ copy_stream_body(VALUE arg)
                 rb_sys_fail_on_write(stp->dst_fptr);
         }
         else /* others such as StringIO */
-	    rb_io_write(dst_io, str);
+            rb_io_write(dst_io, str);
         rb_str_resize(str, 0);
         stp->total += len;
-        if (stp->copy_length >= (off_t)0)
+        if (stp->copy_length >= (rb_off_t)0)
             stp->copy_length -= len;
     }
 
     if (stp->dst_fptr && io_fflush(stp->dst_fptr) < 0) {
-	rb_raise(rb_eIOError, "flush failed");
+        rb_raise(rb_eIOError, "flush failed");
     }
 
     if (stp->copy_length == 0)
@@ -12671,7 +13296,7 @@ copy_stream_finalize(VALUE arg)
         rb_syserr_fail(stp->error_no, stp->syserr);
     }
     if (stp->notimp) {
-	rb_raise(rb_eNotImpError, "%s() not implemented", stp->notimp);
+        rb_raise(rb_eNotImpError, "%s() not implemented", stp->notimp);
     }
     return Qnil;
 }
@@ -12744,12 +13369,12 @@ rb_io_s_copy_stream(int argc, VALUE *argv, VALUE io)
     st.dst_fptr = NULL;
 
     if (NIL_P(length))
-        st.copy_length = (off_t)-1;
+        st.copy_length = (rb_off_t)-1;
     else
         st.copy_length = NUM2OFFT(length);
 
     if (NIL_P(src_offset))
-        st.src_offset = (off_t)-1;
+        st.src_offset = (rb_off_t)-1;
     else
         st.src_offset = NUM2OFFT(src_offset);
 
@@ -12765,7 +13390,7 @@ rb_io_s_copy_stream(int argc, VALUE *argv, VALUE io)
  *  Returns the Encoding object that represents the encoding of the stream,
  *  or +nil+ if the stream is in write mode and no encoding is specified.
  *
- *  See {Encodings}[rdoc-ref:IO@Encodings].
+ *  See {Encodings}[rdoc-ref:File@Encodings].
  *
  */
 
@@ -12775,12 +13400,12 @@ rb_io_external_encoding(VALUE io)
     rb_io_t *fptr = RFILE(rb_io_taint_check(io))->fptr;
 
     if (fptr->encs.enc2) {
-	return rb_enc_from_encoding(fptr->encs.enc2);
+        return rb_enc_from_encoding(fptr->encs.enc2);
     }
     if (fptr->mode & FMODE_WRITABLE) {
-	if (fptr->encs.enc)
-	    return rb_enc_from_encoding(fptr->encs.enc);
-	return Qnil;
+        if (fptr->encs.enc)
+            return rb_enc_from_encoding(fptr->encs.enc);
+        return Qnil;
     }
     return rb_enc_from_encoding(io_read_encoding(fptr));
 }
@@ -12793,7 +13418,7 @@ rb_io_external_encoding(VALUE io)
  *  if conversion is specified,
  *  or +nil+ otherwise.
  *
- *  See {Encodings}[rdoc-ref:IO@Encodings].
+ *  See {Encodings}[rdoc-ref:File@Encodings].
  *
  */
 
@@ -12812,7 +13437,7 @@ rb_io_internal_encoding(VALUE io)
  *    set_encoding(ext_enc, int_enc, **enc_opts)  -> self
  *    set_encoding('ext_enc:int_enc', **enc_opts) -> self
  *
- *  See {Encodings}[rdoc-ref:IO@Encodings].
+ *  See {Encodings}[rdoc-ref:File@Encodings].
  *
  *  Argument +ext_enc+, if given, must be an Encoding object;
  *  it is assigned as the encoding for the stream.
@@ -12874,16 +13499,27 @@ global_argf_p(VALUE arg)
     return arg == argf;
 }
 
+typedef VALUE (*argf_encoding_func)(VALUE io);
+
+static VALUE
+argf_encoding(VALUE argf, argf_encoding_func func)
+{
+    if (!RTEST(ARGF.current_file)) {
+        return rb_enc_default_external();
+    }
+    return func(rb_io_check_io(ARGF.current_file));
+}
+
 /*
  *  call-seq:
  *     ARGF.external_encoding   -> encoding
  *
- *  Returns the external encoding for files read from +ARGF+ as an +Encoding+
+ *  Returns the external encoding for files read from ARGF as an Encoding
  *  object. The external encoding is the encoding of the text as stored in a
- *  file. Contrast with +ARGF.internal_encoding+, which is the encoding used
- *  to represent this text within Ruby.
+ *  file. Contrast with ARGF.internal_encoding, which is the encoding used to
+ *  represent this text within Ruby.
  *
- *  To set the external encoding use +ARGF.set_encoding+.
+ *  To set the external encoding use ARGF.set_encoding.
  *
  *  For example:
  *
@@ -12893,20 +13529,17 @@ global_argf_p(VALUE arg)
 static VALUE
 argf_external_encoding(VALUE argf)
 {
-    if (!RTEST(ARGF.current_file)) {
-	return rb_enc_from_encoding(rb_default_external_encoding());
-    }
-    return rb_io_external_encoding(rb_io_check_io(ARGF.current_file));
+    return argf_encoding(argf, rb_io_external_encoding);
 }
 
 /*
  *  call-seq:
  *     ARGF.internal_encoding   -> encoding
  *
- *  Returns the internal encoding for strings read from +ARGF+ as an
- *  +Encoding+ object.
+ *  Returns the internal encoding for strings read from ARGF as an
+ *  Encoding object.
  *
- *  If +ARGF.set_encoding+ has been called with two encoding names, the second
+ *  If ARGF.set_encoding has been called with two encoding names, the second
  *  is returned. Otherwise, if +Encoding.default_external+ has been set, that
  *  value is returned. Failing that, if a default external encoding was
  *  specified on the command-line, that value is used. If the encoding is
@@ -12915,10 +13548,7 @@ argf_external_encoding(VALUE argf)
 static VALUE
 argf_internal_encoding(VALUE argf)
 {
-    if (!RTEST(ARGF.current_file)) {
-	return rb_enc_from_encoding(rb_default_external_encoding());
-    }
-    return rb_io_internal_encoding(rb_io_check_io(ARGF.current_file));
+    return argf_encoding(argf, rb_io_internal_encoding);
 }
 
 /*
@@ -12942,7 +13572,7 @@ argf_internal_encoding(VALUE argf)
  *  specifies the internal encoding.
  *
  *  If the external encoding and the internal encoding are specified, the
- *  optional +Hash+ argument can be used to adjust the conversion process. The
+ *  optional Hash argument can be used to adjust the conversion process. The
  *  structure of this hash is explained in the String#encode documentation.
  *
  *  For example:
@@ -12958,7 +13588,7 @@ argf_set_encoding(int argc, VALUE *argv, VALUE argf)
     rb_io_t *fptr;
 
     if (!next_argv()) {
-	rb_raise(rb_eArgError, "no stream to set encoding");
+        rb_raise(rb_eArgError, "no stream to set encoding");
     }
     rb_io_set_encoding(argc, argv, ARGF.current_file);
     GetOpenFile(ARGF.current_file, fptr);
@@ -12971,7 +13601,7 @@ argf_set_encoding(int argc, VALUE *argv, VALUE argf)
  *     ARGF.tell  -> Integer
  *     ARGF.pos   -> Integer
  *
- *  Returns the current offset (in bytes) of the current file in +ARGF+.
+ *  Returns the current offset (in bytes) of the current file in ARGF.
  *
  *     ARGF.pos    #=> 0
  *     ARGF.gets   #=> "This is line one\n"
@@ -12982,7 +13612,7 @@ static VALUE
 argf_tell(VALUE argf)
 {
     if (!next_argv()) {
-	rb_raise(rb_eArgError, "no stream to tell");
+        rb_raise(rb_eArgError, "no stream to tell");
     }
     ARGF_FORWARD(0, 0);
     return rb_io_tell(ARGF.current_file);
@@ -12992,14 +13622,14 @@ argf_tell(VALUE argf)
  *  call-seq:
  *     ARGF.seek(amount, whence=IO::SEEK_SET)  -> 0
  *
- *  Seeks to offset _amount_ (an +Integer+) in the +ARGF+ stream according to
+ *  Seeks to offset _amount_ (an Integer) in the ARGF stream according to
  *  the value of _whence_. See IO#seek for further details.
  */
 static VALUE
 argf_seek_m(int argc, VALUE *argv, VALUE argf)
 {
     if (!next_argv()) {
-	rb_raise(rb_eArgError, "no stream to seek");
+        rb_raise(rb_eArgError, "no stream to seek");
     }
     ARGF_FORWARD(argc, argv);
     return rb_io_seek_m(argc, argv, ARGF.current_file);
@@ -13009,7 +13639,7 @@ argf_seek_m(int argc, VALUE *argv, VALUE argf)
  *  call-seq:
  *     ARGF.pos = position  -> Integer
  *
- *  Seeks to the position given by _position_ (in bytes) in +ARGF+.
+ *  Seeks to the position given by _position_ (in bytes) in ARGF.
  *
  *  For example:
  *
@@ -13020,7 +13650,7 @@ static VALUE
 argf_set_pos(VALUE argf, VALUE offset)
 {
     if (!next_argv()) {
-	rb_raise(rb_eArgError, "no stream to set position");
+        rb_raise(rb_eArgError, "no stream to set position");
     }
     ARGF_FORWARD(1, &offset);
     return rb_io_set_pos(ARGF.current_file, offset);
@@ -13031,7 +13661,7 @@ argf_set_pos(VALUE argf, VALUE offset)
  *     ARGF.rewind   -> 0
  *
  *  Positions the current file to the beginning of input, resetting
- *  +ARGF.lineno+ to zero.
+ *  ARGF.lineno to zero.
  *
  *     ARGF.readline   #=> "This is line one\n"
  *     ARGF.rewind     #=> 0
@@ -13045,13 +13675,13 @@ argf_rewind(VALUE argf)
     int old_lineno;
 
     if (!next_argv()) {
-	rb_raise(rb_eArgError, "no stream to rewind");
+        rb_raise(rb_eArgError, "no stream to rewind");
     }
     ARGF_FORWARD(0, 0);
     old_lineno = RFILE(ARGF.current_file)->fptr->lineno;
     ret = rb_io_rewind(ARGF.current_file);
     if (!global_argf_p(argf)) {
-	ARGF.last_lineno = ARGF.lineno -= old_lineno;
+        ARGF.last_lineno = ARGF.lineno -= old_lineno;
     }
     return ret;
 }
@@ -13062,7 +13692,7 @@ argf_rewind(VALUE argf)
  *     ARGF.to_i      -> integer
  *
  *  Returns an integer representing the numeric file descriptor for
- *  the current file. Raises an +ArgumentError+ if there isn't a current file.
+ *  the current file. Raises an ArgumentError if there isn't a current file.
  *
  *     ARGF.fileno    #=> 3
  */
@@ -13070,7 +13700,7 @@ static VALUE
 argf_fileno(VALUE argf)
 {
     if (!next_argv()) {
-	rb_raise(rb_eArgError, "no stream");
+        rb_raise(rb_eArgError, "no stream");
     }
     ARGF_FORWARD(0, 0);
     return rb_io_fileno(ARGF.current_file);
@@ -13080,8 +13710,8 @@ argf_fileno(VALUE argf)
  *  call-seq:
  *     ARGF.to_io     -> IO
  *
- *  Returns an +IO+ object representing the current file. This will be a
- *  +File+ object unless the current file is a stream such as STDIN.
+ *  Returns an IO object representing the current file. This will be a
+ *  File object unless the current file is a stream such as STDIN.
  *
  *  For example:
  *
@@ -13101,8 +13731,8 @@ argf_to_io(VALUE argf)
  *     ARGF.eof?  -> true or false
  *     ARGF.eof   -> true or false
  *
- *  Returns true if the current file in +ARGF+ is at end of file, i.e. it has
- *  no data to read. The stream must be opened for reading or an +IOError+
+ *  Returns true if the current file in ARGF is at end of file, i.e. it has
+ *  no data to read. The stream must be opened for reading or an IOError
  *  will be raised.
  *
  *     $ echo "eof" | ruby argf.rb
@@ -13119,12 +13749,12 @@ argf_eof(VALUE argf)
 {
     next_argv();
     if (RTEST(ARGF.current_file)) {
-	if (ARGF.init_p == 0) return Qtrue;
-	next_argv();
-	ARGF_FORWARD(0, 0);
-	if (rb_io_eof(ARGF.current_file)) {
-	    return Qtrue;
-	}
+        if (ARGF.init_p == 0) return Qtrue;
+        next_argv();
+        ARGF_FORWARD(0, 0);
+        if (rb_io_eof(ARGF.current_file)) {
+            return Qtrue;
+        }
     }
     return Qfalse;
 }
@@ -13185,39 +13815,39 @@ argf_read(int argc, VALUE *argv, VALUE argf)
 
     rb_scan_args(argc, argv, "02", &length, &str);
     if (!NIL_P(length)) {
-	len = NUM2LONG(argv[0]);
+        len = NUM2LONG(argv[0]);
     }
     if (!NIL_P(str)) {
-	StringValue(str);
-	rb_str_resize(str,0);
-	argv[1] = Qnil;
+        StringValue(str);
+        rb_str_resize(str,0);
+        argv[1] = Qnil;
     }
 
   retry:
     if (!next_argv()) {
-	return str;
+        return str;
     }
     if (ARGF_GENERIC_INPUT_P()) {
-	tmp = argf_forward(argc, argv, argf);
+        tmp = argf_forward(argc, argv, argf);
     }
     else {
-	tmp = io_read(argc, argv, ARGF.current_file);
+        tmp = io_read(argc, argv, ARGF.current_file);
     }
     if (NIL_P(str)) str = tmp;
     else if (!NIL_P(tmp)) rb_str_append(str, tmp);
     if (NIL_P(tmp) || NIL_P(length)) {
-	if (ARGF.next_p != -1) {
-	    argf_close(argf);
-	    ARGF.next_p = 1;
-	    goto retry;
-	}
+        if (ARGF.next_p != -1) {
+            argf_close(argf);
+            ARGF.next_p = 1;
+            goto retry;
+        }
     }
     else if (argc >= 1) {
-	long slen = RSTRING_LEN(str);
-	if (slen < len) {
+        long slen = RSTRING_LEN(str);
+        if (slen < len) {
             argv[0] = LONG2NUM(len - slen);
-	    goto retry;
-	}
+            goto retry;
+        }
     }
     return str;
 }
@@ -13300,18 +13930,18 @@ argf_getpartial(int argc, VALUE *argv, VALUE argf, VALUE opts, int nonblock)
     no_exception = no_exception_p(opts);
 
     if (!next_argv()) {
-	if (!NIL_P(str)) {
-	    rb_str_resize(str, 0);
-	}
+        if (!NIL_P(str)) {
+            rb_str_resize(str, 0);
+        }
         rb_eof_error();
     }
     if (ARGF_GENERIC_INPUT_P()) {
         VALUE (*const rescue_does_nothing)(VALUE, VALUE) = 0;
-	struct argf_call_arg arg;
-	arg.argc = argc;
-	arg.argv = argv;
-	arg.argf = argf;
-	tmp = rb_rescue2(argf_forward_call, (VALUE)&arg,
+        struct argf_call_arg arg;
+        arg.argc = argc;
+        arg.argv = argv;
+        arg.argf = argf;
+        tmp = rb_rescue2(argf_forward_call, (VALUE)&arg,
                          rescue_does_nothing, Qnil, rb_eEOFError, (VALUE)0);
     }
     else {
@@ -13325,7 +13955,7 @@ argf_getpartial(int argc, VALUE *argv, VALUE argf, VALUE opts, int nonblock)
         ARGF.next_p = 1;
         if (RARRAY_LEN(ARGF.argv) == 0) {
             return io_nonblock_eof(no_exception);
-	}
+        }
         if (NIL_P(str))
             str = rb_str_new(NULL, 0);
         return str;
@@ -13337,10 +13967,10 @@ argf_getpartial(int argc, VALUE *argv, VALUE argf, VALUE opts, int nonblock)
  *  call-seq:
  *     ARGF.getc  -> String or nil
  *
- *  Reads the next character from +ARGF+ and returns it as a +String+. Returns
+ *  Reads the next character from ARGF and returns it as a String. Returns
  *  +nil+ at the end of the stream.
  *
- *  +ARGF+ treats the files named on the command line as a single file created
+ *  ARGF treats the files named on the command line as a single file created
  *  by concatenating their contents. After returning the last character of the
  *  first file, it returns the first character of the second file, and so on.
  *
@@ -13364,15 +13994,15 @@ argf_getc(VALUE argf)
   retry:
     if (!next_argv()) return Qnil;
     if (ARGF_GENERIC_INPUT_P()) {
-	ch = forward_current(rb_intern("getc"), 0, 0);
+        ch = forward_current(rb_intern("getc"), 0, 0);
     }
     else {
-	ch = rb_io_getc(ARGF.current_file);
+        ch = rb_io_getc(ARGF.current_file);
     }
     if (NIL_P(ch) && ARGF.next_p != -1) {
-	argf_close(argf);
-	ARGF.next_p = 1;
-	goto retry;
+        argf_close(argf);
+        ARGF.next_p = 1;
+        goto retry;
     }
 
     return ch;
@@ -13382,7 +14012,7 @@ argf_getc(VALUE argf)
  *  call-seq:
  *     ARGF.getbyte  -> Integer or nil
  *
- *  Gets the next 8-bit byte (0..255) from +ARGF+. Returns +nil+ if called at
+ *  Gets the next 8-bit byte (0..255) from ARGF. Returns +nil+ if called at
  *  the end of the stream.
  *
  *  For example:
@@ -13404,15 +14034,15 @@ argf_getbyte(VALUE argf)
   retry:
     if (!next_argv()) return Qnil;
     if (!RB_TYPE_P(ARGF.current_file, T_FILE)) {
-	ch = forward_current(rb_intern("getbyte"), 0, 0);
+        ch = forward_current(rb_intern("getbyte"), 0, 0);
     }
     else {
-	ch = rb_io_getbyte(ARGF.current_file);
+        ch = rb_io_getbyte(ARGF.current_file);
     }
     if (NIL_P(ch) && ARGF.next_p != -1) {
-	argf_close(argf);
-	ARGF.next_p = 1;
-	goto retry;
+        argf_close(argf);
+        ARGF.next_p = 1;
+        goto retry;
     }
 
     return ch;
@@ -13422,8 +14052,8 @@ argf_getbyte(VALUE argf)
  *  call-seq:
  *     ARGF.readchar  -> String or nil
  *
- *  Reads the next character from +ARGF+ and returns it as a +String+. Raises
- *  an +EOFError+ after the last character of the last file has been read.
+ *  Reads the next character from ARGF and returns it as a String. Raises
+ *  an EOFError after the last character of the last file has been read.
  *
  *  For example:
  *
@@ -13444,15 +14074,15 @@ argf_readchar(VALUE argf)
   retry:
     if (!next_argv()) rb_eof_error();
     if (!RB_TYPE_P(ARGF.current_file, T_FILE)) {
-	ch = forward_current(rb_intern("getc"), 0, 0);
+        ch = forward_current(rb_intern("getc"), 0, 0);
     }
     else {
-	ch = rb_io_getc(ARGF.current_file);
+        ch = rb_io_getc(ARGF.current_file);
     }
     if (NIL_P(ch) && ARGF.next_p != -1) {
-	argf_close(argf);
-	ARGF.next_p = 1;
-	goto retry;
+        argf_close(argf);
+        ARGF.next_p = 1;
+        goto retry;
     }
 
     return ch;
@@ -13462,8 +14092,8 @@ argf_readchar(VALUE argf)
  *  call-seq:
  *     ARGF.readbyte  -> Integer
  *
- *  Reads the next 8-bit byte from ARGF and returns it as an +Integer+. Raises
- *  an +EOFError+ after the last byte of the last file has been read.
+ *  Reads the next 8-bit byte from ARGF and returns it as an Integer. Raises
+ *  an EOFError after the last byte of the last file has been read.
  *
  *  For example:
  *
@@ -13484,7 +14114,7 @@ argf_readbyte(VALUE argf)
     NEXT_ARGF_FORWARD(0, 0);
     c = argf_getbyte(argf);
     if (NIL_P(c)) {
-	rb_eof_error();
+        rb_eof_error();
     }
     return c;
 }
@@ -13497,7 +14127,7 @@ argf_block_call_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, argf))
     const VALUE current = ARGF.current_file;
     rb_yield_values2(argc, argv);
     if (ARGF.init_p == -1 || current != ARGF.current_file) {
-	rb_iter_break_value(Qundef);
+        rb_iter_break_value(Qundef);
     }
     return Qnil;
 }
@@ -13510,14 +14140,14 @@ static void
 argf_block_call(ID mid, int argc, VALUE *argv, VALUE argf)
 {
     VALUE ret = ARGF_block_call(mid, argc, argv, argf_block_call_i, argf);
-    if (ret != Qundef) ARGF.next_p = 1;
+    if (!UNDEF_P(ret)) ARGF.next_p = 1;
 }
 
 static VALUE
 argf_block_call_line_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, argf))
 {
     if (!global_argf_p(argf)) {
-	ARGF.last_lineno = ++ARGF.lineno;
+        ARGF.last_lineno = ++ARGF.lineno;
     }
     return argf_block_call_i(i, argf, argc, argv, blockarg);
 }
@@ -13526,7 +14156,7 @@ static void
 argf_block_call_line(ID mid, int argc, VALUE *argv, VALUE argf)
 {
     VALUE ret = ARGF_block_call(mid, argc, argv, argf_block_call_line_i, argf);
-    if (ret != Qundef) ARGF.next_p = 1;
+    if (!UNDEF_P(ret)) ARGF.next_p = 1;
 }
 
 /*
@@ -13543,15 +14173,15 @@ argf_block_call_line(ID mid, int argc, VALUE *argv, VALUE argf)
  *  which defaults to your platform's newline character) of each file in
  *  +ARGV+. If a block is supplied, each line in turn will be yielded to the
  *  block, otherwise an enumerator is returned.
- *  The optional _limit_ argument is an +Integer+ specifying the maximum
+ *  The optional _limit_ argument is an Integer specifying the maximum
  *  length of each line; longer lines will be split according to this limit.
  *
  *  This method allows you to treat the files supplied on the command line as
  *  a single file consisting of the concatenation of each named file. After
  *  the last line of the first file has been returned, the first line of the
- *  second file is returned. The +ARGF.filename+ and +ARGF.lineno+ methods can
- *  be used to determine the filename of the current line and line number of
- *  the whole input, respectively.
+ *  second file is returned. The ARGF.filename and ARGF.lineno methods can be
+ *  used to determine the filename of the current line and line number of the
+ *  whole input, respectively.
  *
  *  For example, the following code prints out each line of each named file
  *  prefixed with its line number, displaying the filename once per file:
@@ -13574,7 +14204,7 @@ argf_each_line(int argc, VALUE *argv, VALUE argf)
 {
     RETURN_ENUMERATOR(argf, argc, argv);
     FOREACH_ARGF() {
-	argf_block_call_line(rb_intern("each_line"), argc, argv, argf);
+        argf_block_call_line(rb_intern("each_line"), argc, argv, argf);
     }
     return argf;
 }
@@ -13585,12 +14215,12 @@ argf_each_line(int argc, VALUE *argv, VALUE argf)
  *     ARGF.each_byte                  -> an_enumerator
  *
  *  Iterates over each byte of each file in +ARGV+.
- *  A byte is returned as an +Integer+ in the range 0..255.
+ *  A byte is returned as an Integer in the range 0..255.
  *
  *  This method allows you to treat the files supplied on the command line as
  *  a single file consisting of the concatenation of each named file. After
  *  the last byte of the first file has been returned, the first byte of the
- *  second file is returned. The +ARGF.filename+ method can be used to
+ *  second file is returned. The ARGF.filename method can be used to
  *  determine the filename of the current byte.
  *
  *  If no block is given, an enumerator is returned instead.
@@ -13605,7 +14235,7 @@ argf_each_byte(VALUE argf)
 {
     RETURN_ENUMERATOR(argf, 0, 0);
     FOREACH_ARGF() {
-	argf_block_call(rb_intern("each_byte"), 0, 0, argf);
+        argf_block_call(rb_intern("each_byte"), 0, 0, argf);
     }
     return argf;
 }
@@ -13615,12 +14245,12 @@ argf_each_byte(VALUE argf)
  *     ARGF.each_char {|char| block }  -> ARGF
  *     ARGF.each_char                  -> an_enumerator
  *
- *  Iterates over each character of each file in +ARGF+.
+ *  Iterates over each character of each file in ARGF.
  *
  *  This method allows you to treat the files supplied on the command line as
  *  a single file consisting of the concatenation of each named file. After
  *  the last character of the first file has been returned, the first
- *  character of the second file is returned. The +ARGF.filename+ method can
+ *  character of the second file is returned. The ARGF.filename method can
  *  be used to determine the name of the file in which the current character
  *  appears.
  *
@@ -13631,7 +14261,7 @@ argf_each_char(VALUE argf)
 {
     RETURN_ENUMERATOR(argf, 0, 0);
     FOREACH_ARGF() {
-	argf_block_call(rb_intern("each_char"), 0, 0, argf);
+        argf_block_call(rb_intern("each_char"), 0, 0, argf);
     }
     return argf;
 }
@@ -13641,12 +14271,12 @@ argf_each_char(VALUE argf)
  *     ARGF.each_codepoint {|codepoint| block }  -> ARGF
  *     ARGF.each_codepoint                       -> an_enumerator
  *
- *  Iterates over each codepoint of each file in +ARGF+.
+ *  Iterates over each codepoint of each file in ARGF.
  *
  *  This method allows you to treat the files supplied on the command line as
  *  a single file consisting of the concatenation of each named file. After
  *  the last codepoint of the first file has been returned, the first
- *  codepoint of the second file is returned. The +ARGF.filename+ method can
+ *  codepoint of the second file is returned. The ARGF.filename method can
  *  be used to determine the name of the file in which the current codepoint
  *  appears.
  *
@@ -13657,7 +14287,7 @@ argf_each_codepoint(VALUE argf)
 {
     RETURN_ENUMERATOR(argf, 0, 0);
     FOREACH_ARGF() {
-	argf_block_call(rb_intern("each_codepoint"), 0, 0, argf);
+        argf_block_call(rb_intern("each_codepoint"), 0, 0, argf);
     }
     return argf;
 }
@@ -13701,7 +14331,7 @@ argf_filename_getter(ID id, VALUE *var)
  *  call-seq:
  *     ARGF.file  -> IO or File object
  *
- *  Returns the current file as an +IO+ or +File+ object.
+ *  Returns the current file as an IO or File object.
  *  <code>$stdin</code> is returned when the current file is STDIN.
  *
  *  For example:
@@ -13726,7 +14356,7 @@ argf_file(VALUE argf)
  *  call-seq:
  *     ARGF.binmode  -> ARGF
  *
- *  Puts +ARGF+ into binary mode. Once a stream is in binary mode, it cannot
+ *  Puts ARGF into binary mode. Once a stream is in binary mode, it cannot
  *  be reset to non-binary mode. This option has the following effects:
  *
  *  *  Newline conversion is disabled.
@@ -13747,8 +14377,8 @@ argf_binmode_m(VALUE argf)
  *  call-seq:
  *     ARGF.binmode?  -> true or false
  *
- *  Returns true if +ARGF+ is being read in binary mode; false otherwise.
- *  To enable binary mode use +ARGF.binmode+.
+ *  Returns true if ARGF is being read in binary mode; false otherwise.
+ *  To enable binary mode use ARGF.binmode.
  *
  *  For example:
  *
@@ -13780,8 +14410,8 @@ static VALUE
 argf_skip(VALUE argf)
 {
     if (ARGF.init_p && ARGF.next_p == 0) {
-	argf_close(argf);
-	ARGF.next_p = 1;
+        argf_close(argf);
+        ARGF.next_p = 1;
     }
     return argf;
 }
@@ -13791,7 +14421,7 @@ argf_skip(VALUE argf)
  *     ARGF.close  -> ARGF
  *
  *  Closes the current file and skips to the next file in ARGV. If there are
- *  no more files to open, just closes the current file. +STDIN+ will not be
+ *  no more files to open, just closes the current file. STDIN will not be
  *  closed.
  *
  *  For example:
@@ -13809,7 +14439,7 @@ argf_close_m(VALUE argf)
     next_argv();
     argf_close(argf);
     if (ARGF.next_p != -1) {
-	ARGF.next_p = 1;
+        ARGF.next_p = 1;
     }
     ARGF.lineno = 0;
     return argf;
@@ -13820,7 +14450,7 @@ argf_close_m(VALUE argf)
  *     ARGF.closed?  -> true or false
  *
  *  Returns _true_ if the current file has been closed; _false_ otherwise. Use
- *  +ARGF.close+ to actually close the current file.
+ *  ARGF.close to actually close the current file.
  */
 static VALUE
 argf_closed(VALUE argf)
@@ -13846,9 +14476,9 @@ argf_to_s(VALUE argf)
  *  call-seq:
  *     ARGF.inplace_mode  -> String
  *
- *  Returns the file extension appended to the names of modified files under
- *  in-place edit mode. This value can be set using +ARGF.inplace_mode=+ or
- *  passing the +-i+ switch to the Ruby binary.
+ *  Returns the file extension appended to the names of backup copies of
+ *  modified files under in-place edit mode. This value can be set using
+ *  ARGF.inplace_mode= or passing the +-i+ switch to the Ruby binary.
  */
 static VALUE
 argf_inplace_mode_get(VALUE argf)
@@ -13869,8 +14499,8 @@ opt_i_get(ID id, VALUE *var)
  *     ARGF.inplace_mode = ext  -> ARGF
  *
  *  Sets the filename extension for in-place editing mode to the given String.
- *  Each file being edited has this value appended to its filename. The
- *  modified file is saved under this new name.
+ *  The backup copy of each file being edited has this value appended to its
+ *  filename.
  *
  *  For example:
  *
@@ -13881,20 +14511,21 @@ opt_i_get(ID id, VALUE *var)
  *        print line.sub("foo","bar")
  *      end
  *
- *  Each line of _file.txt_ has the first occurrence of "foo" replaced with
- *  "bar", then the new line is written out to _file.txt.bak_.
+ *  First, _file.txt.bak_ is created as a backup copy of _file.txt_.
+ *  Then, each line of _file.txt_ has the first occurrence of "foo" replaced with
+ *  "bar".
  */
 static VALUE
 argf_inplace_mode_set(VALUE argf, VALUE val)
 {
     if (!RTEST(val)) {
-	ARGF.inplace = Qfalse;
+        ARGF.inplace = Qfalse;
     }
     else if (StringValueCStr(val), !RSTRING_LEN(val)) {
-	ARGF.inplace = Qnil;
+        ARGF.inplace = Qnil;
     }
     else {
-	ARGF.inplace = rb_str_new_frozen(val);
+        ARGF.inplace = rb_str_new_frozen(val);
     }
     return argf;
 }
@@ -13954,7 +14585,7 @@ static VALUE
 argf_write_io(VALUE argf)
 {
     if (!RTEST(ARGF.current_file)) {
-	rb_raise(rb_eIOError, "not opened for writing");
+        rb_raise(rb_eIOError, "not opened for writing");
     }
     return GetWriteIO(ARGF.current_file);
 }
@@ -13984,41 +14615,41 @@ rb_readwrite_syserr_fail(enum rb_io_wait_readwrite waiting, int n, const char *m
     arg = mesg ? rb_str_new2(mesg) : Qnil;
     switch (waiting) {
       case RB_IO_WAIT_WRITABLE:
-	switch (n) {
-	  case EAGAIN:
+        switch (n) {
+          case EAGAIN:
             c = rb_eEAGAINWaitWritable;
-	    break;
+            break;
 #if EAGAIN != EWOULDBLOCK
-	  case EWOULDBLOCK:
+          case EWOULDBLOCK:
             c = rb_eEWOULDBLOCKWaitWritable;
-	    break;
+            break;
 #endif
-	  case EINPROGRESS:
+          case EINPROGRESS:
             c = rb_eEINPROGRESSWaitWritable;
-	    break;
-	  default:
+            break;
+          default:
             rb_mod_syserr_fail_str(rb_mWaitWritable, n, arg);
-	}
+        }
         break;
       case RB_IO_WAIT_READABLE:
-	switch (n) {
-	  case EAGAIN:
+        switch (n) {
+          case EAGAIN:
             c = rb_eEAGAINWaitReadable;
-	    break;
+            break;
 #if EAGAIN != EWOULDBLOCK
-	  case EWOULDBLOCK:
+          case EWOULDBLOCK:
             c = rb_eEWOULDBLOCKWaitReadable;
-	    break;
+            break;
 #endif
-	  case EINPROGRESS:
+          case EINPROGRESS:
             c = rb_eEINPROGRESSWaitReadable;
-	    break;
-	  default:
+            break;
+          default:
             rb_mod_syserr_fail_str(rb_mWaitReadable, n, arg);
-	}
+        }
         break;
       default:
-	rb_bug("invalid read/write type passed to rb_readwrite_sys_fail: %d", waiting);
+        rb_bug("invalid read/write type passed to rb_readwrite_sys_fail: %d", waiting);
     }
     rb_exc_raise(rb_class_new_instance(1, &arg, c));
 }
@@ -14060,9 +14691,9 @@ set_LAST_READ_LINE(VALUE val, ID _x, VALUE *_y)
  * methods exist in two forms,
  *
  * one that returns +nil+ when the end of file is reached, the other
- * raises +EOFError+.
+ * raises EOFError.
  *
- * +EOFError+ is a subclass of +IOError+.
+ * EOFError is a subclass of IOError.
  *
  *    file = File.open("/etc/hosts")
  *    file.read
@@ -14074,11 +14705,11 @@ set_LAST_READ_LINE(VALUE val, ID _x, VALUE *_y)
 /*
  * Document-class:  ARGF
  *
- * +ARGF+ is a stream designed for use in scripts that process files given as
+ * ARGF is a stream designed for use in scripts that process files given as
  * command-line arguments or passed in via STDIN.
  *
  * The arguments passed to your script are stored in the +ARGV+ Array, one
- * argument per element. +ARGF+ assumes that any arguments that aren't
+ * argument per element. ARGF assumes that any arguments that aren't
  * filenames have been removed from +ARGV+. For example:
  *
  *     $ ruby argf.rb --verbose file1 file2
@@ -14087,15 +14718,15 @@ set_LAST_READ_LINE(VALUE val, ID _x, VALUE *_y)
  *     option = ARGV.shift #=> "--verbose"
  *     ARGV  #=> ["file1", "file2"]
  *
- * You can now use +ARGF+ to work with a concatenation of each of these named
- * files. For instance, +ARGF.read+ will return the contents of _file1_
+ * You can now use ARGF to work with a concatenation of each of these named
+ * files. For instance, ARGF.read will return the contents of _file1_
  * followed by the contents of _file2_.
  *
- * After a file in +ARGV+ has been read +ARGF+ removes it from the Array.
+ * After a file in +ARGV+ has been read ARGF removes it from the Array.
  * Thus, after all files have been read +ARGV+ will be empty.
  *
- * You can manipulate +ARGV+ yourself to control what +ARGF+ operates on. If
- * you remove a file from +ARGV+, it is ignored by +ARGF+; if you add files to
+ * You can manipulate +ARGV+ yourself to control what ARGF operates on. If
+ * you remove a file from +ARGV+, it is ignored by ARGF; if you add files to
  * +ARGV+, they are treated as if they were named on the command line. For
  * example:
  *
@@ -14105,7 +14736,7 @@ set_LAST_READ_LINE(VALUE val, ID _x, VALUE *_y)
  *     ARGV.replace ["file2", "file3"]
  *     ARGF.read      # Returns the contents of file2 and file3
  *
- * If +ARGV+ is empty, +ARGF+ acts as if it contained STDIN, i.e. the data
+ * If +ARGV+ is empty, ARGF acts as if it contained STDIN, i.e. the data
  * piped to your script. For example:
  *
  *     $ echo "glark" | ruby -e 'p ARGF.read'
@@ -14124,7 +14755,10 @@ set_LAST_READ_LINE(VALUE val, ID _x, VALUE *_y)
  *  The global constant ARGF (also accessible as <tt>$<</tt>)
  *  provides an IO-like stream that allows access to all file paths
  *  found in ARGV (or found in STDIN if ARGV is empty).
- *  Note that ARGF is not itself a subclass of \IO.
+ *  ARGF is not itself a subclass of \IO.
+ *
+ *  \Class StringIO provides an IO-like stream that handles a String.
+ *  \StringIO is not itself a subclass of \IO.
  *
  *  Important objects based on \IO include:
  *
@@ -14142,20 +14776,23 @@ set_LAST_READ_LINE(VALUE val, ID _x, VALUE *_y)
  *  - Kernel#open: Returns a new \IO object connected to a given source:
  *    stream, file, or subprocess.
  *
- *  An \IO stream has:
+ *  Like a \File stream, an \IO stream has:
  *
  *  - A read/write mode, which may be read-only, write-only, or read/write;
- *    see {Read/Write Mode}[rdoc-ref:IO@Read-2FWrite+Mode].
+ *    see {Read/Write Mode}[rdoc-ref:File@Read-2FWrite+Mode].
  *  - A data mode, which may be text-only or binary;
- *    see {Data Mode}[rdoc-ref:IO@Data+Mode].
+ *    see {Data Mode}[rdoc-ref:File@Data+Mode].
+ *  - Internal and external encodings;
+ *    see {Encodings}[rdoc-ref:File@Encodings].
+ *
+ *  And like other \IO streams, it has:
+ *
  *  - A position, which determines where in the stream the next
  *    read or write is to occur;
  *    see {Position}[rdoc-ref:IO@Position].
  *  - A line number, which is a special, line-oriented, "position"
  *    (different from the position mentioned above);
  *    see {Line Number}[rdoc-ref:IO@Line+Number].
- *  - Internal and external encodings;
- *    see {Encodings}[rdoc-ref:IO@Encodings].
  *
  *  == Extension <tt>io/console</tt>
  *
@@ -14165,213 +14802,146 @@ set_LAST_READ_LINE(VALUE val, ID _x, VALUE *_y)
  *
  *  == Example Files
  *
- *  Many examples here use these filenames and their corresponding files:
- *
- *  - <tt>t.txt</tt>: A text-only file that is assumed to exist via:
- *
- *      text = <<~EOT
- *        First line
- *        Second line
- *
- *        Fourth line
- *        Fifth line
- *      EOT
- *      File.write('t.txt', text)
- *
- *  - <tt>t.dat</tt>: A data file that is assumed to exist via:
- *
- *      data = "\u9990\u9991\u9992\u9993\u9994"
- *      f = File.open('t.dat', 'wb:UTF-16')
- *      f.write(data)
- *      f.close
- *
- *  - <tt>t.rus</tt>: A Russian-language text file that is assumed to exist via:
- *
- *      File.write('t.rus', "\u{442 435 441 442}")
- *
- *  - <tt>t.tmp</tt>: A file that is assumed _not_ to exist.
- *
- *  == Modes
- *
- *  A number of \IO method calls must or may specify a _mode_ for the stream;
- *  the mode determines how stream is to be accessible, including:
+ *  Many examples here use these variables:
  *
- *  - Whether the stream is to be read-only, write-only, or read-write.
- *  - Whether the stream is positioned at its beginning or its end.
- *  - Whether the stream treats data as text-only or binary.
- *  - The external and internal encodings.
+ *    :include: doc/examples/files.rdoc
  *
- *  === Read/Write Mode
- *
- *  ==== Read/Write Mode Specified as an \Integer
- *
- *  When +mode+ is an integer it must be one or more (combined by bitwise OR (<tt>|</tt>)
- *  of the modes defined in File::Constants:
- *
- *  - +File::RDONLY+: Open for reading only.
- *  - +File::WRONLY+: Open for writing only.
- *  - +File::RDWR+: Open for reading and writing.
- *  - +File::APPEND+: Open for appending only.
- *  - +File::CREAT+: Create file if it does not exist.
- *  - +File::EXCL+: Raise an exception if +File::CREAT+ is given and the file exists.
- *
- *  Examples:
+ *  == Open Options
  *
- *    File.new('t.txt', File::RDONLY)
- *    File.new('t.tmp', File::RDWR | File::CREAT | File::EXCL)
+ *  A number of \IO methods accept optional keyword arguments
+ *  that determine how a new stream is to be opened:
  *
- *  Note: Method IO#set_encoding does not allow the mode to be specified as an integer.
+ *  - +:mode+: Stream mode.
+ *  - +:flags+: \Integer file open flags;
+ *    If +mode+ is also given, the two are bitwise-ORed.
+ *  - +:external_encoding+: External encoding for the stream.
+ *  - +:internal_encoding+: Internal encoding for the stream.
+ *    <tt>'-'</tt> is a synonym for the default internal encoding.
+ *    If the value is +nil+ no conversion occurs.
+ *  - +:encoding+: Specifies external and internal encodings as <tt>'extern:intern'</tt>.
+ *  - +:textmode+: If a truthy value, specifies the mode as text-only, binary otherwise.
+ *  - +:binmode+: If a truthy value, specifies the mode as binary, text-only otherwise.
+ *  - +:autoclose+: If a truthy value, specifies that the +fd+ will close
+ *    when the stream closes; otherwise it remains open.
+ *  - +:path:+ If a string value is provided, it is used in #inspect and is available as
+ *    #path method.
  *
- *  ==== Read/Write Mode Specified As a \String
+ *  Also available are the options offered in String#encode,
+ *  which may control conversion between external internal encoding.
  *
- *  When +mode+ is a string it must begin with one of the following:
+ *  == Basic \IO
  *
- *  - <tt>'r'</tt>: Read-only stream, positioned at the beginning;
- *    the stream cannot be changed to writable.
- *  - <tt>'w'</tt>: Write-only stream, positioned at the beginning;
- *    the stream cannot be changed to readable.
- *  - <tt>'a'</tt>: Write-only stream, positioned at the end;
- *    every write appends to the end;
- *    the stream cannot be changed to readable.
- *  - <tt>'r+'</tt>: Read-write stream, positioned at the beginning.
- *  - <tt>'w+'</tt>: Read-write stream, positioned at the end.
- *  - <tt>'a+'</tt>: Read-write stream, positioned at the end.
+ *  You can perform basic stream \IO with these methods,
+ *  which typically operate on multi-byte strings:
  *
- *  For a writable file stream (that is, any except read-only),
- *  the file is truncated to zero if it exists,
- *  and is created if it does not exist.
+ *  - IO#read: Reads and returns some or all of the remaining bytes from the stream.
+ *  - IO#write: Writes zero or more strings to the stream;
+ *    each given object that is not already a string is converted via +to_s+.
  *
- *  Examples:
+ *  === Position
  *
- *    File.open('t.txt', 'r')
- *    File.open('t.tmp', 'w')
+ *  An \IO stream has a nonnegative integer _position_,
+ *  which is the byte offset at which the next read or write is to occur.
+ *  A new stream has position zero (and line number zero);
+ *  method +rewind+ resets the position (and line number) to zero.
  *
- *  === Data Mode
+ *  The relevant methods:
  *
- *  Either of the following may be suffixed to any of the string read/write modes above:
+ *  - IO#tell (aliased as +#pos+): Returns the current position (in bytes) in the stream.
+ *  - IO#pos=: Sets the position of the stream to a given integer +new_position+ (in bytes).
+ *  - IO#seek: Sets the position of the stream to a given integer +offset+ (in bytes),
+ *    relative to a given position +whence+
+ *    (indicating the beginning, end, or current position).
+ *  - IO#rewind: Positions the stream at the beginning (also resetting the line number).
  *
- *  - <tt>'t'</tt>: Text data; sets the default external encoding to +Encoding::UTF_8+;
- *    on Windows, enables conversion between EOL and CRLF.
- *  - <tt>'b'</tt>: Binary data; sets the default external encoding to +Encoding::ASCII_8BIT+;
- *    on Windows, suppresses conversion between EOL and CRLF.
+ *  === Open and Closed Streams
  *
- *  If neither is given, the stream defaults to text data.
+ *  A new \IO stream may be open for reading, open for writing, or both.
  *
- *  Examples:
+ *  A stream is automatically closed when claimed by the garbage collector.
  *
- *    File.open('t.txt', 'rt')
- *    File.open('t.dat', 'rb')
+ *  Attempted reading or writing on a closed stream raises an exception.
  *
- *  The following may be suffixed to any writable string mode above:
+ *  The relevant methods:
  *
- *  - <tt>'x'</tt>: Creates the file if it does not exist;
- *    raises an exception if the file exists.
+ *  - IO#close: Closes the stream for both reading and writing.
+ *  - IO#close_read: Closes the stream for reading.
+ *  - IO#close_write: Closes the stream for writing.
+ *  - IO#closed?: Returns whether the stream is closed.
  *
- *  Example:
+ *  === End-of-Stream
  *
- *    File.open('t.tmp', 'wx')
+ *  You can query whether a stream is positioned at its end:
  *
- *  == Encodings
+ *  - IO#eof? (also aliased as +#eof+): Returns whether the stream is at end-of-stream.
  *
- *  Any of the string modes above may specify encodings --
- *  either external encoding only or both external and internal encodings --
- *  by appending one or both encoding names, separated by colons:
+ *  You can reposition to end-of-stream by using method IO#seek:
  *
- *    f = File.new('t.dat', 'rb')
- *    f.external_encoding # => #<Encoding:ASCII-8BIT>
- *    f.internal_encoding # => nil
- *    f = File.new('t.dat', 'rb:UTF-16')
- *    f.external_encoding # => #<Encoding:UTF-16 (dummy)>
- *    f.internal_encoding # => nil
- *    f = File.new('t.dat', 'rb:UTF-16:UTF-16')
- *    f.external_encoding # => #<Encoding:UTF-16 (dummy)>
- *    f.internal_encoding # => #<Encoding:UTF-16>
+ *    f = File.new('t.txt')
+ *    f.eof? # => false
+ *    f.seek(0, :END)
+ *    f.eof? # => true
  *    f.close
  *
- *  The numerous encoding names are available in array Encoding.name_list:
+ *  Or by reading all stream content (which is slower than using IO#seek):
  *
- *    Encoding.name_list.size    # => 175
- *    Encoding.name_list.take(3) # => ["ASCII-8BIT", "UTF-8", "US-ASCII"]
- *
- *  When the external encoding is set,
- *  strings read are tagged by that encoding
- *  when reading, and strings written are converted to that
- *  encoding when writing.
+ *    f.rewind
+ *    f.eof? # => false
+ *    f.read # => "First line\nSecond line\n\nFourth line\nFifth line\n"
+ *    f.eof? # => true
  *
- *  When both external and internal encodings are set,
- *  strings read are converted from external to internal encoding,
- *  and strings written are converted from internal to external encoding.
- *  For further details about transcoding input and output, see Encoding.
+ *  == Line \IO
  *
- *  If the external encoding is <tt>'BOM|UTF-8'</tt>, <tt>'BOM|UTF-16LE'</tt>
- *  or <tt>'BOM|UTF16-BE'</tt>, Ruby checks for
- *  a Unicode BOM in the input document to help determine the encoding.  For
- *  UTF-16 encodings the file open mode must be binary.
- *  If the BOM is found, it is stripped and the external encoding from the BOM is used.
+ *  You can read an \IO stream line-by-line using these methods:
  *
- *  Note that the BOM-style encoding option is case insensitive,
- *  so 'bom|utf-8' is also valid.)
+ *  - IO#each_line: Reads each remaining line, passing it to the given block.
+ *  - IO#gets: Returns the next line.
+ *  - IO#readline: Like #gets, but raises an exception at end-of-stream.
+ *  - IO#readlines: Returns all remaining lines in an array.
  *
- *  == Open Options
+ *  Each of these reader methods accepts:
  *
- *  A number of \IO methods accept optional keyword arguments
- *  that determine how a new stream is to be opened:
+ *  - An optional line separator, +sep+;
+ *    see {Line Separator}[rdoc-ref:IO@Line+Separator].
+ *  - An optional line-size limit, +limit+;
+ *    see {Line Limit}[rdoc-ref:IO@Line+Limit].
  *
- *  - +:mode+: Stream mode.
- *  - +:flags+: \Integer file open flags;
- *    If +mode+ is also given, the two are bitwise-ORed.
- *  - +:external_encoding+: External encoding for the stream.
- *  - +:internal_encoding+: Internal encoding for the stream.
- *    <tt>'-'</tt> is a synonym for the default internal encoding.
- *    If the value is +nil+ no conversion occurs.
- *  - +:encoding+: Specifies external and internal encodings as <tt>'extern:intern'</tt>.
- *  - +:textmode+: If a truthy value, specifies the mode as text-only, binary otherwise.
- *  - +:binmode+: If a truthy value, specifies the mode as binary, text-only otherwise.
- *  - +:autoclose+: If a truthy value, specifies that the +fd+ will close
- *    when the stream closes; otherwise it remains open.
- *
- *  Also available are the options offered in String#encode,
- *  which may control conversion between external internal encoding.
+ *  For each of these reader methods, reading may begin mid-line,
+ *  depending on the stream's position;
+ *  see {Position}[rdoc-ref:IO@Position]:
  *
- *  == Lines
+ *    f = File.new('t.txt')
+ *    f.pos = 27
+ *    f.each_line {|line| p line }
+ *    f.close
  *
- *  Some reader methods in \IO are line-oriented;
- *  such a method reads one or more lines,
- *  which are separated by an implicit or explicit line separator.
+ *  Output:
  *
- *  These methods include:
+ *    "rth line\n"
+ *    "Fifth line\n"
  *
- *  - Kernel#gets
- *  - Kernel#readline
- *  - Kernel#readlines
- *  - IO.foreach
- *  - IO.readlines
- *  - IO#each_line
- *  - IO#gets
- *  - IO#readline
- *  - IO#readlines
- *  - ARGF.each
- *  - ARGF.gets
- *  - ARGF.readline
- *  - ARGF.readlines
+ *  You can write to an \IO stream line-by-line using this method:
  *
- *  Each of these methods returns +nil+ if called when already at end-of-stream,
- *  except for IO#readline, which raises an exception.
+ *  - IO#puts: Writes objects to the stream.
  *
- *  Each of these methods may be called with:
+ *  === Line Separator
  *
- *  - An optional line separator, +sep+.
- *  - An optional line-size limit, +limit+.
- *  - Both +sep+ and +limit+.
+ *  Each of these methods uses a <i>line separator</i>,
+ *  which is the string that delimits lines:
  *
- *  === Line Separator
+ *  - IO.foreach.
+ *  - IO.readlines.
+ *  - IO#each_line.
+ *  - IO#gets.
+ *  - IO#readline.
+ *  - IO#readlines.
  *
  *  The default line separator is the given by the global variable <tt>$/</tt>,
- *  whose value is often <tt>"\n"</tt>.
+ *  whose value is by default <tt>"\n"</tt>.
  *  The line to be read next is all data from the current position
  *  to the next line separator:
  *
- *    f = File.open('t.txt')
+ *    f = File.new('t.txt')
  *    f.gets # => "First line\n"
  *    f.gets # => "Second line\n"
  *    f.gets # => "\n"
@@ -14406,9 +14976,18 @@ set_LAST_READ_LINE(VALUE val, ID _x, VALUE *_y)
  *
  *  === Line Limit
  *
- *  The line to be read may be further defined by an optional argument +limit+,
- *  which specifies that the line may not be (much) longer than the given limit;
- *  a multi-byte character will not be split, and so a line may be slightly longer
+ *  Each of these methods uses a <i>line limit</i>,
+ *  which specifies that the number of bytes returned may not be (much) longer
+ *  than the given +limit+;
+ *
+ *  - IO.foreach.
+ *  - IO.readlines.
+ *  - IO#each_line.
+ *  - IO#gets.
+ *  - IO#readline.
+ *  - IO#readlines.
+ *
+ *  A multi-byte character will not be split, and so a line may be slightly longer
  *  than the given limit.
  *
  *  If +limit+ is not given, the line is determined only by +sep+.
@@ -14424,10 +15003,10 @@ set_LAST_READ_LINE(VALUE val, ID _x, VALUE *_y)
  *    File.open('t.txt') {|f| f.gets(12) } # => "First line\n"
  *
  *    # Text with 2-byte characters, which will not be split.
- *    File.open('r.rus') {|f| f.gets(1).size } # => 1
- *    File.open('r.rus') {|f| f.gets(2).size } # => 1
- *    File.open('r.rus') {|f| f.gets(3).size } # => 2
- *    File.open('r.rus') {|f| f.gets(4).size } # => 2
+ *    File.open('t.rus') {|f| f.gets(1).size } # => 1
+ *    File.open('t.rus') {|f| f.gets(2).size } # => 1
+ *    File.open('t.rus') {|f| f.gets(3).size } # => 2
+ *    File.open('t.rus') {|f| f.gets(4).size } # => 2
  *
  *  === Line Separator and Line Limit
  *
@@ -14444,17 +15023,38 @@ set_LAST_READ_LINE(VALUE val, ID _x, VALUE *_y)
  *
  *  === Line Number
  *
- *  A readable \IO stream has a _line_ _number_,
- *  which is the non-negative integer line number
- *  in the stream where the next read will occur.
+ *  A readable \IO stream has a non-negative integer <i>line number</i>.
+ *
+ *  The relevant methods:
+ *
+ *  - IO#lineno: Returns the line number.
+ *  - IO#lineno=: Resets and returns the line number.
  *
- *  A new stream is initially has line number +0+.
+ *  Unless modified by a call to method IO#lineno=,
+ *  the line number is the number of lines read
+ *  by certain line-oriented methods,
+ *  according to the given line separator +sep+:
  *
- *  \Method IO#lineno returns the line number.
+ *  - IO.foreach: Increments the line number on each call to the block.
+ *  - IO#each_line: Increments the line number on each call to the block.
+ *  - IO#gets: Increments the line number.
+ *  - IO#readline: Increments the line number.
+ *  - IO#readlines: Increments the line number for each line read.
+ *
+ *  A new stream is initially has line number zero (and position zero);
+ *  method +rewind+ resets the line number (and position) to zero:
+ *
+ *    f = File.new('t.txt')
+ *    f.lineno # => 0
+ *    f.gets   # => "First line\n"
+ *    f.lineno # => 1
+ *    f.rewind
+ *    f.lineno # => 0
+ *    f.close
  *
  *  Reading lines from a stream usually changes its line number:
  *
- *    f = File.open('t.txt', 'r')
+ *    f = File.new('t.txt', 'r')
  *    f.lineno   # => 0
  *    f.readline # => "This is line one.\n"
  *    f.lineno   # => 1
@@ -14467,24 +15067,87 @@ set_LAST_READ_LINE(VALUE val, ID _x, VALUE *_y)
  *
  *  Iterating over lines in a stream usually changes its line number:
  *
- *       f = File.open('t.txt')
- *       f.each_line do |line|
- *         p "position=#{f.pos} eof?=#{f.eof?} line=#{line}"
- *       end
- *       f.close
+ *    File.open('t.txt') do |f|
+ *      f.each_line do |line|
+ *        p "position=#{f.pos} eof?=#{f.eof?} lineno=#{f.lineno}"
+ *      end
+ *    end
  *
  *  Output:
  *
- *   "position=19 eof?=false line=This is line one.\n"
- *   "position=45 eof?=false line=This is the second line.\n"
- *   "position=70 eof?=true line=This is the third line.\n"
+ *    "position=11 eof?=false lineno=1"
+ *    "position=23 eof?=false lineno=2"
+ *    "position=24 eof?=false lineno=3"
+ *    "position=36 eof?=false lineno=4"
+ *    "position=47 eof?=true lineno=5"
  *
- *  === Line Options
+ *  Unlike the stream's {position}[rdoc-ref:IO@Position],
+ *  the line number does not affect where the next read or write will occur:
  *
- *  A number of \IO methods accept optional keyword arguments
- *  that determine how lines in a stream are to be treated:
+ *    f = File.new('t.txt')
+ *    f.lineno = 1000
+ *    f.lineno # => 1000
+ *    f.gets   # => "First line\n"
+ *    f.lineno # => 1001
+ *    f.close
+ *
+ *  Associated with the line number is the global variable <tt>$.</tt>:
+ *
+ *  - When a stream is opened, <tt>$.</tt> is not set;
+ *    its value is left over from previous activity in the process:
+ *
+ *      $. = 41
+ *      f = File.new('t.txt')
+ *      $. = 41
+ *      # => 41
+ *      f.close
+ *
+ *  - When a stream is read, <tt>#.</tt> is set to the line number for that stream:
+ *
+ *      f0 = File.new('t.txt')
+ *      f1 = File.new('t.dat')
+ *      f0.readlines # => ["First line\n", "Second line\n", "\n", "Fourth line\n", "Fifth line\n"]
+ *      $.           # => 5
+ *      f1.readlines # => ["\xFE\xFF\x99\x90\x99\x91\x99\x92\x99\x93\x99\x94"]
+ *      $.           # => 1
+ *      f0.close
+ *      f1.close
+ *
+ *  - Methods IO#rewind and IO#seek do not affect <tt>$.</tt>:
+ *
+ *      f = File.new('t.txt')
+ *      f.readlines # => ["First line\n", "Second line\n", "\n", "Fourth line\n", "Fifth line\n"]
+ *      $.          # => 5
+ *      f.rewind
+ *      f.seek(0, :SET)
+ *      $.          # => 5
+ *      f.close
+ *
+ *  == Character \IO
+ *
+ *  You can process an \IO stream character-by-character using these methods:
+ *
+ *  - IO#getc: Reads and returns the next character from the stream.
+ *  - IO#readchar: Like #getc, but raises an exception at end-of-stream.
+ *  - IO#ungetc: Pushes back ("unshifts") a character or integer onto the stream.
+ *  - IO#putc: Writes a character to the stream.
+ *  - IO#each_char: Reads each remaining character in the stream,
+ *    passing the character to the given block.
+ *  == Byte \IO
  *
- *  - +:chomp+: If +true+, line separators are omitted; default is +false+.
+ *  You can process an \IO stream byte-by-byte using these methods:
+ *
+ *  - IO#getbyte: Returns the next 8-bit byte as an integer in range 0..255.
+ *  - IO#readbyte: Like #getbyte, but raises an exception if at end-of-stream.
+ *  - IO#ungetbyte: Pushes back ("unshifts") a byte back onto the stream.
+ *  - IO#each_byte: Reads each remaining byte in the stream,
+ *    passing the byte to the given block.
+ *
+ *  == Codepoint \IO
+ *
+ *  You can process an \IO stream codepoint-by-codepoint:
+ *
+ *  - IO#each_codepoint: Reads each remaining codepoint, passing it to the given block.
  *
  *  == What's Here
  *
@@ -14533,11 +15196,11 @@ set_LAST_READ_LINE(VALUE val, ID _x, VALUE *_y)
  *  - #read_nonblock: the next _n_ bytes read from +self+ for a given _n_,
  *    in non-block mode.
  *  - #readbyte: Returns the next byte read from +self+;
- *    same as #getbyte, but raises an exception on end-of-file.
+ *    same as #getbyte, but raises an exception on end-of-stream.
  *  - #readchar: Returns the next character read from +self+;
- *    same as #getc, but raises an exception on end-of-file.
+ *    same as #getc, but raises an exception on end-of-stream.
  *  - #readline: Returns the next line read from +self+;
- *    same as #getline, but raises an exception of end-of-file.
+ *    same as #getline, but raises an exception of end-of-stream.
  *  - #readlines: Returns an array of all lines read read from +self+.
  *  - #readpartial: Returns up to the given number of bytes from +self+.
  *
@@ -14597,7 +15260,7 @@ set_LAST_READ_LINE(VALUE val, ID _x, VALUE *_y)
  *  - #binmode?: Returns whether +self+ is in binary mode.
  *  - #close_on_exec?: Returns the close-on-exec flag for +self+.
  *  - #closed?: Returns whether +self+ is closed.
- *  - #eof? (aliased as #eof): Returns whether +self+ is at end-of-file.
+ *  - #eof? (aliased as #eof): Returns whether +self+ is at end-of-stream.
  *  - #external_encoding: Returns the external encoding object for +self+.
  *  - #fileno (aliased as #to_i): Returns the integer file descriptor for +self+
  *  - #internal_encoding: Returns the internal encoding object for +self+.
@@ -14647,11 +15310,11 @@ Init_IO(void)
 #include <sys/cygwin.h>
     static struct __cygwin_perfile pf[] =
     {
-	{"", O_RDONLY | O_BINARY},
-	{"", O_WRONLY | O_BINARY},
-	{"", O_RDWR | O_BINARY},
-	{"", O_APPEND | O_BINARY},
-	{NULL, 0}
+        {"", O_RDONLY | O_BINARY},
+        {"", O_WRONLY | O_BINARY},
+        {"", O_RDWR | O_BINARY},
+        {"", O_APPEND | O_BINARY},
+        {NULL, 0}
     };
     cygwin_internal(CW_PERFILE, pf);
 #endif
@@ -14688,6 +15351,8 @@ Init_IO(void)
     rb_cIO = rb_define_class("IO", rb_cObject);
     rb_include_module(rb_cIO, rb_mEnumerable);
 
+    rb_eIOTimeoutError = rb_define_class_under(rb_cIO, "TimeoutError", rb_eIOError);
+
     rb_define_const(rb_cIO, "READABLE", INT2NUM(RUBY_IO_READABLE));
     rb_define_const(rb_cIO, "WRITABLE", INT2NUM(RUBY_IO_WRITABLE));
     rb_define_const(rb_cIO, "PRIORITY", INT2NUM(RUBY_IO_PRIORITY));
@@ -14786,23 +15451,26 @@ Init_IO(void)
     rb_define_alias(rb_cIO, "to_i", "fileno");
     rb_define_method(rb_cIO, "to_io", rb_io_to_io, 0);
 
-    rb_define_method(rb_cIO, "fsync",   rb_io_fsync, 0);
-    rb_define_method(rb_cIO, "fdatasync",   rb_io_fdatasync, 0);
-    rb_define_method(rb_cIO, "sync",   rb_io_sync, 0);
-    rb_define_method(rb_cIO, "sync=",  rb_io_set_sync, 1);
+    rb_define_method(rb_cIO, "timeout", rb_io_timeout, 0);
+    rb_define_method(rb_cIO, "timeout=", rb_io_set_timeout, 1);
 
-    rb_define_method(rb_cIO, "lineno",   rb_io_lineno, 0);
-    rb_define_method(rb_cIO, "lineno=",  rb_io_set_lineno, 1);
+    rb_define_method(rb_cIO, "fsync", rb_io_fsync, 0);
+    rb_define_method(rb_cIO, "fdatasync", rb_io_fdatasync, 0);
+    rb_define_method(rb_cIO, "sync", rb_io_sync, 0);
+    rb_define_method(rb_cIO, "sync=", rb_io_set_sync, 1);
 
-    rb_define_method(rb_cIO, "readlines",  rb_io_readlines, -1);
+    rb_define_method(rb_cIO, "lineno", rb_io_lineno, 0);
+    rb_define_method(rb_cIO, "lineno=", rb_io_set_lineno, 1);
 
-    rb_define_method(rb_cIO, "readpartial",  io_readpartial, -1);
-    rb_define_method(rb_cIO, "read",  io_read, -1);
+    rb_define_method(rb_cIO, "readlines", rb_io_readlines, -1);
+
+    rb_define_method(rb_cIO, "readpartial", io_readpartial, -1);
+    rb_define_method(rb_cIO, "read", io_read, -1);
     rb_define_method(rb_cIO, "write", io_write_m, -1);
-    rb_define_method(rb_cIO, "gets",  rb_io_gets_m, -1);
-    rb_define_method(rb_cIO, "readline",  rb_io_readline, -1);
-    rb_define_method(rb_cIO, "getc",  rb_io_getc, 0);
-    rb_define_method(rb_cIO, "getbyte",  rb_io_getbyte, 0);
+    rb_define_method(rb_cIO, "gets", rb_io_gets_m, -1);
+    rb_define_method(rb_cIO, "readline", rb_io_readline, -1);
+    rb_define_method(rb_cIO, "getc", rb_io_getc, 0);
+    rb_define_method(rb_cIO, "getbyte", rb_io_getbyte, 0);
     rb_define_method(rb_cIO, "readchar",  rb_io_readchar, 0);
     rb_define_method(rb_cIO, "readbyte",  rb_io_readbyte, 0);
     rb_define_method(rb_cIO, "ungetbyte",rb_io_ungetbyte, 1);
@@ -14849,6 +15517,10 @@ Init_IO(void)
     rb_define_method(rb_cIO, "ioctl", rb_io_ioctl, -1);
     rb_define_method(rb_cIO, "fcntl", rb_io_fcntl, -1);
     rb_define_method(rb_cIO, "pid", rb_io_pid, 0);
+
+    rb_define_method(rb_cIO, "path", rb_io_path, 0);
+    rb_define_method(rb_cIO, "to_path", rb_io_path, 0);
+
     rb_define_method(rb_cIO, "inspect",  rb_io_inspect, 0);
 
     rb_define_method(rb_cIO, "external_encoding", rb_io_external_encoding, 0);
@@ -14859,6 +15531,12 @@ Init_IO(void)
     rb_define_method(rb_cIO, "autoclose?", rb_io_autoclose_p, 0);
     rb_define_method(rb_cIO, "autoclose=", rb_io_set_autoclose, 1);
 
+    rb_define_method(rb_cIO, "wait", io_wait, -1);
+
+    rb_define_method(rb_cIO, "wait_readable", io_wait_readable, -1);
+    rb_define_method(rb_cIO, "wait_writable", io_wait_writable, -1);
+    rb_define_method(rb_cIO, "wait_priority", io_wait_priority, -1);
+
     rb_define_virtual_variable("$stdin",  stdin_getter,  stdin_setter);
     rb_define_virtual_variable("$stdout", stdout_getter, stdout_setter);
     rb_define_virtual_variable("$>",      stdout_getter, stdout_setter);
@@ -14869,13 +15547,12 @@ Init_IO(void)
     rb_gvar_ractor_local("$>");
     rb_gvar_ractor_local("$stderr");
 
-    rb_stdin  = rb_io_prep_stdin();
-    rb_stdout = rb_io_prep_stdout();
-    rb_stderr = rb_io_prep_stderr();
-
     rb_global_variable(&rb_stdin);
+    rb_stdin  = rb_io_prep_stdin();
     rb_global_variable(&rb_stdout);
+    rb_stdout = rb_io_prep_stdout();
     rb_global_variable(&rb_stderr);
+    rb_stderr = rb_io_prep_stderr();
 
     orig_stdout = rb_stdout;
     orig_stderr = rb_stderr;
diff --git a/io_buffer.c b/io_buffer.c
index fb18e729a6..87b51c0b8c 100644
--- a/io_buffer.c
+++ b/io_buffer.c
@@ -11,15 +11,19 @@
 #include "ruby/fiber/scheduler.h"
 
 #include "internal.h"
-#include "internal/string.h"
+#include "internal/array.h"
 #include "internal/bits.h"
 #include "internal/error.h"
+#include "internal/numeric.h"
+#include "internal/string.h"
+#include "internal/thread.h"
 
 VALUE rb_cIOBuffer;
 VALUE rb_eIOBufferLockedError;
 VALUE rb_eIOBufferAllocationError;
 VALUE rb_eIOBufferAccessError;
 VALUE rb_eIOBufferInvalidatedError;
+VALUE rb_eIOBufferMaskError;
 
 size_t RUBY_IO_BUFFER_PAGE_SIZE;
 size_t RUBY_IO_BUFFER_DEFAULT_SIZE;
@@ -43,7 +47,7 @@ struct rb_io_buffer {
 };
 
 static inline void *
-io_buffer_map_memory(size_t size)
+io_buffer_map_memory(size_t size, int flags)
 {
 #if defined(_WIN32)
     void * base = VirtualAlloc(0, size, MEM_COMMIT, PAGE_READWRITE);
@@ -52,7 +56,15 @@ io_buffer_map_memory(size_t size)
         rb_sys_fail("io_buffer_map_memory:VirtualAlloc");
     }
 #else
-    void * base = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0);
+    int mmap_flags = MAP_ANONYMOUS;
+    if (flags & RB_IO_BUFFER_SHARED) {
+        mmap_flags |= MAP_SHARED;
+    }
+    else {
+        mmap_flags |= MAP_PRIVATE;
+    }
+
+    void * base = mmap(NULL, size, PROT_READ | PROT_WRITE, mmap_flags, -1, 0);
 
     if (base == MAP_FAILED) {
         rb_sys_fail("io_buffer_map_memory:mmap");
@@ -63,7 +75,7 @@ io_buffer_map_memory(size_t size)
 }
 
 static void
-io_buffer_map_file(struct rb_io_buffer *data, int descriptor, size_t size, off_t offset, enum rb_io_buffer_flags flags)
+io_buffer_map_file(struct rb_io_buffer *buffer, int descriptor, size_t size, rb_off_t offset, enum rb_io_buffer_flags flags)
 {
 #if defined(_WIN32)
     HANDLE file = (HANDLE)_get_osfhandle(descriptor);
@@ -72,7 +84,7 @@ io_buffer_map_file(struct rb_io_buffer *data, int descriptor, size_t size, off_t
     DWORD protect = PAGE_READONLY, access = FILE_MAP_READ;
 
     if (flags & RB_IO_BUFFER_READONLY) {
-        data->flags |= RB_IO_BUFFER_READONLY;
+        buffer->flags |= RB_IO_BUFFER_READONLY;
     }
     else {
         protect = PAGE_READWRITE;
@@ -84,10 +96,12 @@ io_buffer_map_file(struct rb_io_buffer *data, int descriptor, size_t size, off_t
 
     if (flags & RB_IO_BUFFER_PRIVATE) {
         access |= FILE_MAP_COPY;
-        data->flags |= RB_IO_BUFFER_PRIVATE;
-    } else {
-        // This buffer refers to external data.
-        data->flags |= RB_IO_BUFFER_EXTERNAL;
+        buffer->flags |= RB_IO_BUFFER_PRIVATE;
+    }
+    else {
+        // This buffer refers to external buffer.
+        buffer->flags |= RB_IO_BUFFER_EXTERNAL;
+        buffer->flags |= RB_IO_BUFFER_SHARED;
     }
 
     void *base = MapViewOfFile(mapping, access, (DWORD)(offset >> 32), (DWORD)(offset & 0xFFFFFFFF), size);
@@ -97,23 +111,24 @@ io_buffer_map_file(struct rb_io_buffer *data, int descriptor, size_t size, off_t
         rb_sys_fail("io_buffer_map_file:MapViewOfFile");
     }
 
-    data->mapping = mapping;
+    buffer->mapping = mapping;
 #else
     int protect = PROT_READ, access = 0;
 
     if (flags & RB_IO_BUFFER_READONLY) {
-        data->flags |= RB_IO_BUFFER_READONLY;
+        buffer->flags |= RB_IO_BUFFER_READONLY;
     }
     else {
         protect |= PROT_WRITE;
     }
 
     if (flags & RB_IO_BUFFER_PRIVATE) {
-        data->flags |= RB_IO_BUFFER_PRIVATE;
+        buffer->flags |= RB_IO_BUFFER_PRIVATE;
     }
     else {
-        // This buffer refers to external data.
-        data->flags |= RB_IO_BUFFER_EXTERNAL;
+        // This buffer refers to external buffer.
+        buffer->flags |= RB_IO_BUFFER_EXTERNAL;
+        buffer->flags |= RB_IO_BUFFER_SHARED;
         access |= MAP_SHARED;
     }
 
@@ -124,10 +139,10 @@ io_buffer_map_file(struct rb_io_buffer *data, int descriptor, size_t size, off_t
     }
 #endif
 
-    data->base = base;
-    data->size = size;
+    buffer->base = base;
+    buffer->size = size;
 
-    data->flags |= RB_IO_BUFFER_MAPPED;
+    buffer->flags |= RB_IO_BUFFER_MAPPED;
 }
 
 static inline void
@@ -157,18 +172,18 @@ io_buffer_experimental(void)
 }
 
 static void
-io_buffer_zero(struct rb_io_buffer *data)
+io_buffer_zero(struct rb_io_buffer *buffer)
 {
-    data->base = NULL;
-    data->size = 0;
+    buffer->base = NULL;
+    buffer->size = 0;
 #if defined(_WIN32)
-    data->mapping = NULL;
+    buffer->mapping = NULL;
 #endif
-    data->source = Qnil;
+    buffer->source = Qnil;
 }
 
 static void
-io_buffer_initialize(struct rb_io_buffer *data, void *base, size_t size, enum rb_io_buffer_flags flags, VALUE source)
+io_buffer_initialize(struct rb_io_buffer *buffer, void *base, size_t size, enum rb_io_buffer_flags flags, VALUE source)
 {
     if (base) {
         // If we are provided a pointer, we use it.
@@ -179,50 +194,53 @@ io_buffer_initialize(struct rb_io_buffer *data, void *base, size_t size, enum rb
             base = calloc(size, 1);
         }
         else if (flags & RB_IO_BUFFER_MAPPED) {
-            base = io_buffer_map_memory(size);
+            base = io_buffer_map_memory(size, flags);
         }
 
         if (!base) {
             rb_raise(rb_eIOBufferAllocationError, "Could not allocate buffer!");
         }
-    } else {
+    }
+    else {
         // Otherwise we don't do anything.
         return;
     }
 
-    data->base = base;
-    data->size = size;
-    data->flags = flags;
-    data->source = source;
+    buffer->base = base;
+    buffer->size = size;
+    buffer->flags = flags;
+    buffer->source = source;
 }
 
 static int
-io_buffer_free(struct rb_io_buffer *data)
+io_buffer_free(struct rb_io_buffer *buffer)
 {
-    if (data->base) {
-        if (data->flags & RB_IO_BUFFER_INTERNAL) {
-            free(data->base);
+    if (buffer->base) {
+        if (buffer->flags & RB_IO_BUFFER_INTERNAL) {
+            free(buffer->base);
         }
 
-        if (data->flags & RB_IO_BUFFER_MAPPED) {
-            io_buffer_unmap(data->base, data->size);
+        if (buffer->flags & RB_IO_BUFFER_MAPPED) {
+            io_buffer_unmap(buffer->base, buffer->size);
         }
 
-        if (RB_TYPE_P(data->source, T_STRING)) {
-            rb_str_unlocktmp(data->source);
-        }
+        // Previously we had this, but we found out due to the way GC works, we
+        // can't refer to any other Ruby objects here.
+        // if (RB_TYPE_P(buffer->source, T_STRING)) {
+        //     rb_str_unlocktmp(buffer->source);
+        // }
 
-        data->base = NULL;
+        buffer->base = NULL;
 
 #if defined(_WIN32)
-        if (data->mapping) {
-            CloseHandle(data->mapping);
-            data->mapping = NULL;
+        if (buffer->mapping) {
+            CloseHandle(buffer->mapping);
+            buffer->mapping = NULL;
         }
 #endif
-        data->size = 0;
-        data->flags = 0;
-        data->source = Qnil;
+        buffer->size = 0;
+        buffer->flags = 0;
+        buffer->source = Qnil;
 
         return 1;
     }
@@ -231,30 +249,30 @@ io_buffer_free(struct rb_io_buffer *data)
 }
 
 void
-rb_io_buffer_type_mark(void *_data)
+rb_io_buffer_type_mark(void *_buffer)
 {
-    struct rb_io_buffer *data = _data;
-    rb_gc_mark(data->source);
+    struct rb_io_buffer *buffer = _buffer;
+    rb_gc_mark(buffer->source);
 }
 
 void
-rb_io_buffer_type_free(void *_data)
+rb_io_buffer_type_free(void *_buffer)
 {
-    struct rb_io_buffer *data = _data;
+    struct rb_io_buffer *buffer = _buffer;
 
-    io_buffer_free(data);
+    io_buffer_free(buffer);
 
-    free(data);
+    free(buffer);
 }
 
 size_t
-rb_io_buffer_type_size(const void *_data)
+rb_io_buffer_type_size(const void *_buffer)
 {
-    const struct rb_io_buffer *data = _data;
+    const struct rb_io_buffer *buffer = _buffer;
     size_t total = sizeof(struct rb_io_buffer);
 
-    if (data->flags) {
-        total += data->size;
+    if (buffer->flags) {
+        total += buffer->size;
     }
 
     return total;
@@ -271,32 +289,195 @@ static const rb_data_type_t rb_io_buffer_type = {
     .flags = RUBY_TYPED_FREE_IMMEDIATELY,
 };
 
+// Extract an offset argument, which must be a positive integer.
+static inline size_t
+io_buffer_extract_offset(VALUE argument)
+{
+    if (rb_int_negative_p(argument)) {
+        rb_raise(rb_eArgError, "Offset can't be negative!");
+    }
+
+    return NUM2SIZET(argument);
+}
+
+// Extract a length argument, which must be a positive integer.
+// Length is generally considered a mutable property of an object and
+// semantically should be considered a subset of "size" as a concept.
+static inline size_t
+io_buffer_extract_length(VALUE argument)
+{
+    if (rb_int_negative_p(argument)) {
+        rb_raise(rb_eArgError, "Length can't be negative!");
+    }
+
+    return NUM2SIZET(argument);
+}
+
+// Extract a size argument, which must be a positive integer.
+// Size is generally considered an immutable property of an object.
+static inline size_t
+io_buffer_extract_size(VALUE argument)
+{
+    if (rb_int_negative_p(argument)) {
+        rb_raise(rb_eArgError, "Size can't be negative!");
+    }
+
+    return NUM2SIZET(argument);
+}
+
+// Compute the default length for a buffer, given an offset into that buffer.
+// The default length is the size of the buffer minus the offset. The offset
+// must be less than the size of the buffer otherwise the length will be
+// invalid; in that case, an ArgumentError exception will be raised.
+static inline size_t
+io_buffer_default_length(const struct rb_io_buffer *buffer, size_t offset)
+{
+    if (offset > buffer->size) {
+        rb_raise(rb_eArgError, "The given offset is bigger than the buffer size!");
+    }
+
+    // Note that the "length" is computed by the size the offset.
+    return buffer->size - offset;
+}
+
+// Extract the optional length and offset arguments, returning the buffer.
+// The length and offset are optional, but if they are provided, they must be
+// positive integers. If the length is not provided, the default length is
+// computed from the buffer size and offset. If the offset is not provided, it
+// defaults to zero.
+static inline struct rb_io_buffer *
+io_buffer_extract_length_offset(VALUE self, int argc, VALUE argv[], size_t *length, size_t *offset)
+{
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
+
+    if (argc >= 2) {
+        *offset = io_buffer_extract_offset(argv[1]);
+    }
+    else {
+        *offset = 0;
+    }
+
+    if (argc >= 1 && !NIL_P(argv[0])) {
+        *length = io_buffer_extract_length(argv[0]);
+    }
+    else {
+        *length = io_buffer_default_length(buffer, *offset);
+    }
+
+    return buffer;
+}
+
+// Extract the optional offset and length arguments, returning the buffer.
+// Similar to `io_buffer_extract_length_offset` but with the order of
+// arguments reversed.
+static inline struct rb_io_buffer *
+io_buffer_extract_offset_length(VALUE self, int argc, VALUE argv[], size_t *offset, size_t *length)
+{
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
+
+    if (argc >= 1) {
+        *offset = io_buffer_extract_offset(argv[0]);
+    }
+    else {
+        *offset = 0;
+    }
+
+    if (argc >= 2) {
+        *length = io_buffer_extract_length(argv[1]);
+    }
+    else {
+        *length = io_buffer_default_length(buffer, *offset);
+    }
+
+    return buffer;
+}
+
 VALUE
 rb_io_buffer_type_allocate(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    VALUE instance = TypedData_Make_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    VALUE instance = TypedData_Make_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
+
+    io_buffer_zero(buffer);
+
+    return instance;
+}
+
+static VALUE io_buffer_for_make_instance(VALUE klass, VALUE string, enum rb_io_buffer_flags flags)
+{
+    VALUE instance = rb_io_buffer_type_allocate(klass);
+
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(instance, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    io_buffer_zero(data);
+    flags |= RB_IO_BUFFER_EXTERNAL;
+
+    if (RB_OBJ_FROZEN(string))
+        flags |= RB_IO_BUFFER_READONLY;
+
+    if (!(flags & RB_IO_BUFFER_READONLY))
+        rb_str_modify(string);
+
+    io_buffer_initialize(buffer, RSTRING_PTR(string), RSTRING_LEN(string), flags, string);
 
     return instance;
 }
 
+struct io_buffer_for_yield_instance_arguments {
+    VALUE klass;
+    VALUE string;
+    VALUE instance;
+    enum rb_io_buffer_flags flags;
+};
+
+static VALUE
+io_buffer_for_yield_instance(VALUE _arguments)
+{
+    struct io_buffer_for_yield_instance_arguments *arguments = (struct io_buffer_for_yield_instance_arguments *)_arguments;
+
+    arguments->instance = io_buffer_for_make_instance(arguments->klass, arguments->string, arguments->flags);
+
+    rb_str_locktmp(arguments->string);
+
+    return rb_yield(arguments->instance);
+}
+
+static VALUE
+io_buffer_for_yield_instance_ensure(VALUE _arguments)
+{
+    struct io_buffer_for_yield_instance_arguments *arguments = (struct io_buffer_for_yield_instance_arguments *)_arguments;
+
+    if (arguments->instance != Qnil) {
+        rb_io_buffer_free(arguments->instance);
+    }
+
+    rb_str_unlocktmp(arguments->string);
+
+    return Qnil;
+}
+
 /*
- *  call-seq: IO::Buffer.for(string) -> io_buffer
+ *  call-seq:
+ *    IO::Buffer.for(string) -> readonly io_buffer
+ *    IO::Buffer.for(string) {|io_buffer| ... read/write io_buffer ...}
  *
- *  Creates a IO::Buffer from the given string's memory. The buffer remains
- *  associated with the string, and writing to a buffer will update the string's
- *  contents.
+ *  Creates a IO::Buffer from the given string's memory. Without a block a
+ *  frozen internal copy of the string is created efficiently and used as the
+ *  buffer source. When a block is provided, the buffer is associated directly
+ *  with the string's internal buffer and updating the buffer will update the
+ *  string.
  *
  *  Until #free is invoked on the buffer, either explicitly or via the garbage
  *  collector, the source string will be locked and cannot be modified.
  *
  *  If the string is frozen, it will create a read-only buffer which cannot be
- *  modified.
+ *  modified. If the string is shared, it may trigger a copy-on-write when
+ *  using the block form.
  *
  *    string = 'test'
- *    buffer = IO::Buffer.for(str)
+ *    buffer = IO::Buffer.for(string)
  *    buffer.external? #=> true
  *
  *    buffer.get_string(0, 1)
@@ -306,29 +487,35 @@ rb_io_buffer_type_allocate(VALUE self)
  *
  *    buffer.resize(100)
  *    # in `resize': Cannot resize external buffer! (IO::Buffer::AccessError)
+ *
+ *    IO::Buffer.for(string) do |buffer|
+ *      buffer.set_string("T")
+ *      string
+ *      # => "Test"
+ *    end
  */
 VALUE
 rb_io_buffer_type_for(VALUE klass, VALUE string)
 {
-    io_buffer_experimental();
-
     StringValue(string);
 
-    VALUE instance = rb_io_buffer_type_allocate(klass);
-
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(instance, struct rb_io_buffer, &rb_io_buffer_type, data);
+    // If the string is frozen, both code paths are okay.
+    // If the string is not frozen, if a block is not given, it must be frozen.
+    if (rb_block_given_p()) {
+        struct io_buffer_for_yield_instance_arguments arguments = {
+            .klass = klass,
+            .string = string,
+            .instance = Qnil,
+            .flags = 0,
+        };
 
-    rb_str_locktmp(string);
-
-    enum rb_io_buffer_flags flags = RB_IO_BUFFER_EXTERNAL;
-
-    if (RB_OBJ_FROZEN(string))
-        flags |= RB_IO_BUFFER_READONLY;
-
-    io_buffer_initialize(data, RSTRING_PTR(string), RSTRING_LEN(string), flags, string);
-
-    return instance;
+        return rb_ensure(io_buffer_for_yield_instance, (VALUE)&arguments, io_buffer_for_yield_instance_ensure, (VALUE)&arguments);
+    }
+    else {
+        // This internally returns the source string if it's already frozen.
+        string = rb_str_tmp_frozen_acquire(string);
+        return io_buffer_for_make_instance(klass, string, RB_IO_BUFFER_READONLY);
+    }
 }
 
 VALUE
@@ -336,27 +523,27 @@ rb_io_buffer_new(void *base, size_t size, enum rb_io_buffer_flags flags)
 {
     VALUE instance = rb_io_buffer_type_allocate(rb_cIOBuffer);
 
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(instance, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(instance, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    io_buffer_initialize(data, base, size, flags, Qnil);
+    io_buffer_initialize(buffer, base, size, flags, Qnil);
 
     return instance;
 }
 
 VALUE
-rb_io_buffer_map(VALUE io, size_t size, off_t offset, enum rb_io_buffer_flags flags)
+rb_io_buffer_map(VALUE io, size_t size, rb_off_t offset, enum rb_io_buffer_flags flags)
 {
     io_buffer_experimental();
 
     VALUE instance = rb_io_buffer_type_allocate(rb_cIOBuffer);
 
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(instance, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(instance, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
     int descriptor = rb_io_descriptor(io);
 
-    io_buffer_map_file(data, descriptor, size, offset, flags);
+    io_buffer_map_file(buffer, descriptor, size, offset, flags);
 
     return instance;
 }
@@ -373,48 +560,47 @@ rb_io_buffer_map(VALUE io, size_t size, off_t offset, enum rb_io_buffer_flags fl
  *  mapping, you need to open a file in read-write mode, and explicitly pass
  *  +flags+ argument without IO::Buffer::IMMUTABLE.
  *
- *     File.write('test.txt', 'test')
+ *  Example:
  *
- *     buffer = IO::Buffer.map(File.open('test.txt'), nil, 0, IO::Buffer::READONLY)
- *     # => #<IO::Buffer 0x00000001014a0000+4 MAPPED READONLY>
+ *    File.write('test.txt', 'test')
  *
- *     buffer.readonly?   # => true
+ *    buffer = IO::Buffer.map(File.open('test.txt'), nil, 0, IO::Buffer::READONLY)
+ *    # => #<IO::Buffer 0x00000001014a0000+4 MAPPED READONLY>
  *
- *     buffer.get_string
- *     # => "test"
+ *    buffer.readonly?   # => true
  *
- *     buffer.set_string('b', 0)
- *     # `set_string': Buffer is not writable! (IO::Buffer::AccessError)
+ *    buffer.get_string
+ *    # => "test"
  *
- *     # create read/write mapping: length 4 bytes, offset 0, flags 0
- *     buffer = IO::Buffer.map(File.open('test.txt', 'r+'), 4, 0)
- *     buffer.set_string('b', 0)
- *     # => 1
+ *    buffer.set_string('b', 0)
+ *    # `set_string': Buffer is not writable! (IO::Buffer::AccessError)
  *
- *     # Check it
- *     File.read('test.txt')
- *     # => "best"
+ *    # create read/write mapping: length 4 bytes, offset 0, flags 0
+ *    buffer = IO::Buffer.map(File.open('test.txt', 'r+'), 4, 0)
+ *    buffer.set_string('b', 0)
+ *    # => 1
+ *
+ *    # Check it
+ *    File.read('test.txt')
+ *    # => "best"
  *
  *  Note that some operating systems may not have cache coherency between mapped
  *  buffers and file reads.
- *
  */
 static VALUE
 io_buffer_map(int argc, VALUE *argv, VALUE klass)
 {
-    if (argc < 1 || argc > 4) {
-        rb_error_arity(argc, 2, 4);
-    }
+    rb_check_arity(argc, 1, 4);
 
     // We might like to handle a string path?
     VALUE io = argv[0];
 
     size_t size;
     if (argc >= 2 && !RB_NIL_P(argv[1])) {
-        size = RB_NUM2SIZE(argv[1]);
+        size = io_buffer_extract_size(argv[1]);
     }
     else {
-        off_t file_size = rb_file_size(io);
+        rb_off_t file_size = rb_file_size(io);
 
         // Compiler can confirm that we handled file_size < 0 case:
         if (file_size < 0) {
@@ -430,7 +616,8 @@ io_buffer_map(int argc, VALUE *argv, VALUE klass)
         }
     }
 
-    off_t offset = 0;
+    // This is the file offset, not the buffer offset:
+    rb_off_t offset = 0;
     if (argc >= 3) {
         offset = NUM2OFFT(argv[2]);
     }
@@ -460,7 +647,7 @@ io_flags_for_size(size_t size)
  *  Create a new zero-filled IO::Buffer of +size+ bytes.
  *  By default, the buffer will be _internal_: directly allocated chunk
  *  of the memory. But if the requested +size+ is more than OS-specific
- *  IO::Bufer::PAGE_SIZE, the buffer would be allocated using the
+ *  IO::Buffer::PAGE_SIZE, the buffer would be allocated using the
  *  virtual memory mechanism (anonymous +mmap+ on Unix, +VirtualAlloc+
  *  on Windows). The behavior can be forced by passing IO::Buffer::MAPPED
  *  as a second parameter.
@@ -469,35 +656,32 @@ io_flags_for_size(size_t size)
  *
  *    buffer = IO::Buffer.new(4)
  *    # =>
- *    #  #<IO::Buffer 0x000055b34497ea10+4 INTERNAL>
- *    #  0x00000000  00 00 00 00                                     ....
+ *    # #<IO::Buffer 0x000055b34497ea10+4 INTERNAL>
+ *    # 0x00000000  00 00 00 00                                     ....
  *
  *    buffer.get_string(0, 1) # => "\x00"
  *
  *    buffer.set_string("test")
  *    buffer
- *    #  =>
+ *    # =>
  *    # #<IO::Buffer 0x000055b34497ea10+4 INTERNAL>
  *    # 0x00000000  74 65 73 74                                     test
- *
  */
 VALUE
 rb_io_buffer_initialize(int argc, VALUE *argv, VALUE self)
 {
     io_buffer_experimental();
 
-    if (argc < 0 || argc > 2) {
-        rb_error_arity(argc, 0, 2);
-    }
+    rb_check_arity(argc, 0, 2);
 
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
     size_t size;
-
     if (argc > 0) {
-        size = RB_NUM2SIZE(argv[0]);
-    } else {
+        size = io_buffer_extract_size(argv[0]);
+    }
+    else {
         size = RUBY_IO_BUFFER_DEFAULT_SIZE;
     }
 
@@ -509,7 +693,7 @@ rb_io_buffer_initialize(int argc, VALUE *argv, VALUE self)
         flags |= io_flags_for_size(size);
     }
 
-    io_buffer_initialize(data, NULL, size, flags, Qnil);
+    io_buffer_initialize(buffer, NULL, size, flags, Qnil);
 
     return self;
 }
@@ -544,11 +728,11 @@ io_buffer_validate_slice(VALUE source, void *base, size_t size)
 }
 
 static int
-io_buffer_validate(struct rb_io_buffer *data)
+io_buffer_validate(struct rb_io_buffer *buffer)
 {
-    if (data->source != Qnil) {
+    if (buffer->source != Qnil) {
         // Only slices incur this overhead, unfortunately... better safe than sorry!
-        return io_buffer_validate_slice(data->source, data->base, data->size);
+        return io_buffer_validate_slice(buffer->source, buffer->base, buffer->size);
     }
     else {
         return 1;
@@ -563,48 +747,51 @@ io_buffer_validate(struct rb_io_buffer *data)
  *
  *    puts IO::Buffer.new(4) # uses to_s internally
  *    # #<IO::Buffer 0x000055769f41b1a0+4 INTERNAL>
- *
  */
 VALUE
 rb_io_buffer_to_s(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
     VALUE result = rb_str_new_cstr("#<");
 
     rb_str_append(result, rb_class_name(CLASS_OF(self)));
-    rb_str_catf(result, " %p+%"PRIdSIZE, data->base, data->size);
+    rb_str_catf(result, " %p+%"PRIdSIZE, buffer->base, buffer->size);
 
-    if (data->base == NULL) {
+    if (buffer->base == NULL) {
         rb_str_cat2(result, " NULL");
     }
 
-    if (data->flags & RB_IO_BUFFER_EXTERNAL) {
+    if (buffer->flags & RB_IO_BUFFER_EXTERNAL) {
         rb_str_cat2(result, " EXTERNAL");
     }
 
-    if (data->flags & RB_IO_BUFFER_INTERNAL) {
+    if (buffer->flags & RB_IO_BUFFER_INTERNAL) {
         rb_str_cat2(result, " INTERNAL");
     }
 
-    if (data->flags & RB_IO_BUFFER_MAPPED) {
+    if (buffer->flags & RB_IO_BUFFER_MAPPED) {
         rb_str_cat2(result, " MAPPED");
     }
 
-    if (data->flags & RB_IO_BUFFER_LOCKED) {
+    if (buffer->flags & RB_IO_BUFFER_SHARED) {
+        rb_str_cat2(result, " SHARED");
+    }
+
+    if (buffer->flags & RB_IO_BUFFER_LOCKED) {
         rb_str_cat2(result, " LOCKED");
     }
 
-    if (data->flags & RB_IO_BUFFER_READONLY) {
+    if (buffer->flags & RB_IO_BUFFER_READONLY) {
         rb_str_cat2(result, " READONLY");
     }
 
-    if (data->source != Qnil) {
+    if (buffer->source != Qnil) {
         rb_str_cat2(result, " SLICE");
     }
 
-    if (!io_buffer_validate(data)) {
+    if (!io_buffer_validate(buffer)) {
         rb_str_cat2(result, " INVALID");
     }
 
@@ -620,10 +807,11 @@ io_buffer_hexdump(VALUE string, size_t width, char *base, size_t size, int first
     for (size_t offset = 0; offset < size; offset += width) {
         memset(text, '\0', width);
         if (first) {
-            rb_str_catf(string, "0x%08zx ", offset);
+            rb_str_catf(string, "0x%08" PRIxSIZE " ", offset);
             first = 0;
-        } else {
-            rb_str_catf(string, "\n0x%08zx ", offset);
+        }
+        else {
+            rb_str_catf(string, "\n0x%08" PRIxSIZE " ", offset);
         }
 
         for (size_t i = 0; i < width; i += 1) {
@@ -653,15 +841,15 @@ io_buffer_hexdump(VALUE string, size_t width, char *base, size_t size, int first
 static VALUE
 rb_io_buffer_hexdump(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
     VALUE result = Qnil;
 
-    if (io_buffer_validate(data) && data->base) {
-        result = rb_str_buf_new(data->size*3 + (data->size/16)*12 + 1);
+    if (io_buffer_validate(buffer) && buffer->base) {
+        result = rb_str_buf_new(buffer->size*3 + (buffer->size/16)*12 + 1);
 
-        io_buffer_hexdump(result, 16, data->base, data->size, 1);
+        io_buffer_hexdump(result, 16, buffer->base, buffer->size, 1);
     }
 
     return result;
@@ -670,15 +858,15 @@ rb_io_buffer_hexdump(VALUE self)
 VALUE
 rb_io_buffer_inspect(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
     VALUE result = rb_io_buffer_to_s(self);
 
-    if (io_buffer_validate(data)) {
-        // Limit the maximum size genearted by inspect.
-        if (data->size <= 256) {
-            io_buffer_hexdump(result, 16, data->base, data->size, 0);
+    if (io_buffer_validate(buffer)) {
+        // Limit the maximum size generated by inspect.
+        if (buffer->size <= 256) {
+            io_buffer_hexdump(result, 16, buffer->base, buffer->size, 0);
         }
     }
 
@@ -690,33 +878,31 @@ rb_io_buffer_inspect(VALUE self)
  *
  *  Returns the size of the buffer that was explicitly set (on creation with ::new
  *  or on #resize), or deduced on buffer's creation from string or file.
- *
  */
 VALUE
 rb_io_buffer_size(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    return SIZET2NUM(data->size);
+    return SIZET2NUM(buffer->size);
 }
 
 /*
  *  call-seq: valid? -> true or false
  *
- *  Returns whether the buffer data is accessible.
+ *  Returns whether the buffer buffer is accessible.
  *
  *  A buffer becomes invalid if it is a slice of another buffer which has been
  *  freed.
- *
  */
 static VALUE
 rb_io_buffer_valid_p(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    return RBOOL(io_buffer_validate(data));
+    return RBOOL(io_buffer_validate(buffer));
 }
 
 /*
@@ -724,15 +910,14 @@ rb_io_buffer_valid_p(VALUE self)
  *
  *  If the buffer was freed with #free or was never allocated in the first
  *  place.
- *
  */
 static VALUE
 rb_io_buffer_null_p(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    return RBOOL(data->base == NULL);
+    return RBOOL(buffer->base == NULL);
 }
 
 /*
@@ -741,15 +926,14 @@ rb_io_buffer_null_p(VALUE self)
  *  If the buffer has 0 size: it is created by ::new with size 0, or with ::for
  *  from an empty string. (Note that empty files can't be mapped, so the buffer
  *  created with ::map will never be empty.)
- *
  */
 static VALUE
 rb_io_buffer_empty_p(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    return RBOOL(data->size == 0);
+    return RBOOL(buffer->size == 0);
 }
 
 /*
@@ -762,15 +946,14 @@ rb_io_buffer_empty_p(VALUE self)
  *  memory.
  *
  *  External buffer can't be resized.
- *
  */
 static VALUE
 rb_io_buffer_external_p(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    return RBOOL(data->flags & RB_IO_BUFFER_EXTERNAL);
+    return RBOOL(buffer->flags & RB_IO_BUFFER_EXTERNAL);
 }
 
 /*
@@ -788,15 +971,14 @@ rb_io_buffer_external_p(VALUE self)
  *
  *  Internal buffers can be resized, and such an operation will typically
  *  invalidate all slices, but not always.
- *
  */
 static VALUE
 rb_io_buffer_internal_p(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    return RBOOL(data->flags & RB_IO_BUFFER_INTERNAL);
+    return RBOOL(buffer->flags & RB_IO_BUFFER_INTERNAL);
 }
 
 /*
@@ -811,15 +993,30 @@ rb_io_buffer_internal_p(VALUE self)
  *
  *  Mapped buffers can usually be resized, and such an operation will typically
  *  invalidate all slices, but not always.
- *
  */
 static VALUE
 rb_io_buffer_mapped_p(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    return RBOOL(data->flags & RB_IO_BUFFER_MAPPED);
+    return RBOOL(buffer->flags & RB_IO_BUFFER_MAPPED);
+}
+
+/*
+ *  call-seq: shared? -> true or false
+ *
+ *  If the buffer is _shared_, meaning it references memory that can be shared
+ *  with other processes (and thus might change without being modified
+ *  locally).
+ */
+static VALUE
+rb_io_buffer_shared_p(VALUE self)
+{
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
+
+    return RBOOL(buffer->flags & RB_IO_BUFFER_SHARED);
 }
 
 /*
@@ -832,27 +1029,28 @@ rb_io_buffer_mapped_p(VALUE self)
  *  Locking is not thread safe, but is a semantic used to ensure buffers don't
  *  move while being used by a system call.
  *
+ *  Example:
+ *
  *    buffer.locked do
  *      buffer.write(io) # theoretical system call interface
  *    end
- *
  */
 static VALUE
 rb_io_buffer_locked_p(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    return RBOOL(data->flags & RB_IO_BUFFER_LOCKED);
+    return RBOOL(buffer->flags & RB_IO_BUFFER_LOCKED);
 }
 
 int
 rb_io_buffer_readonly_p(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    return data->flags & RB_IO_BUFFER_READONLY;
+    return buffer->flags & RB_IO_BUFFER_READONLY;
 }
 
 /*
@@ -862,7 +1060,6 @@ rb_io_buffer_readonly_p(VALUE self)
  *  #set_value, #set_string or #copy and similar.
  *
  *  Frozen strings and read-only files create read-only buffers.
- *
  */
 static VALUE
 io_buffer_readonly_p(VALUE self)
@@ -870,32 +1067,44 @@ io_buffer_readonly_p(VALUE self)
     return RBOOL(rb_io_buffer_readonly_p(self));
 }
 
-VALUE
-rb_io_buffer_lock(VALUE self)
+static void
+io_buffer_lock(struct rb_io_buffer *buffer)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
-
-    if (data->flags & RB_IO_BUFFER_LOCKED) {
+    if (buffer->flags & RB_IO_BUFFER_LOCKED) {
         rb_raise(rb_eIOBufferLockedError, "Buffer already locked!");
     }
 
-    data->flags |= RB_IO_BUFFER_LOCKED;
-
-    return self;
+    buffer->flags |= RB_IO_BUFFER_LOCKED;
 }
 
 VALUE
-rb_io_buffer_unlock(VALUE self)
+rb_io_buffer_lock(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
+
+    io_buffer_lock(buffer);
+
+    return self;
+}
 
-    if (!(data->flags & RB_IO_BUFFER_LOCKED)) {
+static void
+io_buffer_unlock(struct rb_io_buffer *buffer)
+{
+    if (!(buffer->flags & RB_IO_BUFFER_LOCKED)) {
         rb_raise(rb_eIOBufferLockedError, "Buffer not locked!");
     }
 
-    data->flags &= ~RB_IO_BUFFER_LOCKED;
+    buffer->flags &= ~RB_IO_BUFFER_LOCKED;
+}
+
+VALUE
+rb_io_buffer_unlock(VALUE self)
+{
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
+
+    io_buffer_unlock(buffer);
 
     return self;
 }
@@ -903,11 +1112,11 @@ rb_io_buffer_unlock(VALUE self)
 int
 rb_io_buffer_try_unlock(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    if (data->flags & RB_IO_BUFFER_LOCKED) {
-        data->flags &= ~RB_IO_BUFFER_LOCKED;
+    if (buffer->flags & RB_IO_BUFFER_LOCKED) {
+        buffer->flags &= ~RB_IO_BUFFER_LOCKED;
         return 1;
     }
 
@@ -922,6 +1131,14 @@ rb_io_buffer_try_unlock(VALUE self)
  *  can enter the lock. Also, locked buffer can't be changed with #resize or
  *  #free.
  *
+ *  The following operations acquire a lock: #resize, #free.
+ *
+ *  Locking is not thread safe. It is designed as a safety net around
+ *  non-blocking system calls. You can only share a buffer between threads with
+ *  appropriate synchronisation techniques.
+ *
+ *  Example:
+ *
  *    buffer = IO::Buffer.new(4)
  *    buffer.locked? #=> false
  *
@@ -937,28 +1154,22 @@ rb_io_buffer_try_unlock(VALUE self)
  *        buffer.set_string("test", 0)
  *      end
  *    end
- *
- *  The following operations acquire a lock: #resize, #free.
- *
- *  Locking is not thread safe. It is designed as a safety net around
- *  non-blocking system calls. You can only share a buffer between threads with
- *  appropriate synchronisation techniques.
  */
 VALUE
 rb_io_buffer_locked(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    if (data->flags & RB_IO_BUFFER_LOCKED) {
+    if (buffer->flags & RB_IO_BUFFER_LOCKED) {
         rb_raise(rb_eIOBufferLockedError, "Buffer already locked!");
     }
 
-    data->flags |= RB_IO_BUFFER_LOCKED;
+    buffer->flags |= RB_IO_BUFFER_LOCKED;
 
     VALUE result = rb_yield(self);
 
-    data->flags &= ~RB_IO_BUFFER_LOCKED;
+    buffer->flags &= ~RB_IO_BUFFER_LOCKED;
 
     return result;
 }
@@ -973,47 +1184,73 @@ rb_io_buffer_locked(VALUE self)
  *
  *  After the buffer is freed, no further operations can't be performed on it.
  *
- *     buffer = IO::Buffer.for('test')
- *     buffer.free
- *     # => #<IO::Buffer 0x0000000000000000+0 NULL>
+ *  You can resize a freed buffer to re-allocate it.
  *
- *     buffer.get_value(:U8, 0)
- *     # in `get_value': The buffer is not allocated! (IO::Buffer::AllocationError)
+ *  Example:
  *
- *     buffer.get_string
- *     # in `get_string': The buffer is not allocated! (IO::Buffer::AllocationError)
+ *    buffer = IO::Buffer.for('test')
+ *    buffer.free
+ *    # => #<IO::Buffer 0x0000000000000000+0 NULL>
  *
- *     buffer.null?
- *     # => true
+ *    buffer.get_value(:U8, 0)
+ *    # in `get_value': The buffer is not allocated! (IO::Buffer::AllocationError)
  *
- *  You can resize a freed buffer to re-allocate it.
+ *    buffer.get_string
+ *    # in `get_string': The buffer is not allocated! (IO::Buffer::AllocationError)
  *
+ *    buffer.null?
+ *    # => true
  */
 VALUE
 rb_io_buffer_free(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    if (data->flags & RB_IO_BUFFER_LOCKED) {
+    if (buffer->flags & RB_IO_BUFFER_LOCKED) {
         rb_raise(rb_eIOBufferLockedError, "Buffer is locked!");
     }
 
-    io_buffer_free(data);
+    io_buffer_free(buffer);
 
     return self;
 }
 
+// Validate that access to the buffer is within bounds, assuming you want to
+// access length bytes from the specified offset.
 static inline void
-io_buffer_validate_range(struct rb_io_buffer *data, size_t offset, size_t length)
+io_buffer_validate_range(struct rb_io_buffer *buffer, size_t offset, size_t length)
 {
-    if (offset + length > data->size) {
-        rb_raise(rb_eArgError, "Specified offset+length exceeds data size!");
+    // We assume here that offset + length won't overflow:
+    if (offset + length > buffer->size) {
+        rb_raise(rb_eArgError, "Specified offset+length is bigger than the buffer size!");
     }
 }
 
+static VALUE
+rb_io_buffer_slice(struct rb_io_buffer *buffer, VALUE self, size_t offset, size_t length)
+{
+    io_buffer_validate_range(buffer, offset, length);
+
+    VALUE instance = rb_io_buffer_type_allocate(rb_class_of(self));
+    struct rb_io_buffer *slice = NULL;
+    TypedData_Get_Struct(instance, struct rb_io_buffer, &rb_io_buffer_type, slice);
+
+    slice->flags |= (buffer->flags & RB_IO_BUFFER_READONLY);
+    slice->base = (char*)buffer->base + offset;
+    slice->size = length;
+
+    // The source should be the root buffer:
+    if (buffer->source != Qnil)
+        slice->source = buffer->source;
+    else
+        slice->source = self;
+
+    return instance;
+}
+
 /*
- *  call-seq: slice(offset, length) -> io_buffer
+ *  call-seq: slice([offset, [length]]) -> io_buffer
  *
  *  Produce another IO::Buffer which is a slice (or view into) the current one
  *  starting at +offset+ bytes and going for +length+ bytes.
@@ -1021,75 +1258,76 @@ io_buffer_validate_range(struct rb_io_buffer *data, size_t offset, size_t length
  *  The slicing happens without copying of memory, and the slice keeps being
  *  associated with the original buffer's source (string, or file), if any.
  *
- *  Raises RuntimeError if the <tt>offset+length<tt> is out of the current
+ *  If the offset is not given, it will be zero. If the offset is negative, it
+ *  will raise an ArgumentError.
+ *
+ *  If the length is not given, the slice will be as long as the original
+ *  buffer minus the specified offset. If the length is negative, it will raise
+ *  an ArgumentError.
+ *
+ *  Raises RuntimeError if the <tt>offset+length</tt> is out of the current
  *  buffer's bounds.
  *
- *     string = 'test'
- *     buffer = IO::Buffer.for(string)
+ *  Example:
  *
- *     slice = buffer.slice(1, 2)
- *     # =>
- *     #  #<IO::Buffer 0x00007fc3d34ebc49+2 SLICE>
- *     #  0x00000000  65 73                                           es
+ *    string = 'test'
+ *    buffer = IO::Buffer.for(string)
  *
- *     # Put "o" into 0s position of the slice
- *     slice.set_string('o', 0)
- *     slice
- *     # =>
- *     #  #<IO::Buffer 0x00007fc3d34ebc49+2 SLICE>
- *     #  0x00000000  6f 73                                           os
+ *    slice = buffer.slice
+ *    # =>
+ *    # #<IO::Buffer 0x0000000108338e68+4 SLICE>
+ *    # 0x00000000  74 65 73 74                                     test
+ *
+ *    buffer.slice(2)
+ *    # =>
+ *    # #<IO::Buffer 0x0000000108338e6a+2 SLICE>
+ *    # 0x00000000  73 74                                           st
  *
+ *    slice = buffer.slice(1, 2)
+ *    # =>
+ *    # #<IO::Buffer 0x00007fc3d34ebc49+2 SLICE>
+ *    # 0x00000000  65 73                                           es
  *
- *     # it is also visible at position 1 of the original buffer
- *     buffer
- *     # =>
- *     #  #<IO::Buffer 0x00007fc3d31e2d80+4 SLICE>
- *     #  0x00000000  74 6f 73 74                                     tost
+ *    # Put "o" into 0s position of the slice
+ *    slice.set_string('o', 0)
+ *    slice
+ *    # =>
+ *    # #<IO::Buffer 0x00007fc3d34ebc49+2 SLICE>
+ *    # 0x00000000  6f 73                                           os
  *
- *     # ...and original string
- *     string
- *     # => tost
+ *    # it is also visible at position 1 of the original buffer
+ *    buffer
+ *    # =>
+ *    # #<IO::Buffer 0x00007fc3d31e2d80+4 SLICE>
+ *    # 0x00000000  74 6f 73 74                                     tost
  *
+ *    # ...and original string
+ *    string
+ *    # => tost
  */
-VALUE
-rb_io_buffer_slice(VALUE self, VALUE _offset, VALUE _length)
+static VALUE
+io_buffer_slice(int argc, VALUE *argv, VALUE self)
 {
-    // TODO fail on negative offets/lengths.
-    size_t offset = NUM2SIZET(_offset);
-    size_t length = NUM2SIZET(_length);
-
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
-
-    io_buffer_validate_range(data, offset, length);
+    rb_check_arity(argc, 0, 2);
 
-    VALUE instance = rb_io_buffer_type_allocate(rb_class_of(self));
-    struct rb_io_buffer *slice = NULL;
-    TypedData_Get_Struct(instance, struct rb_io_buffer, &rb_io_buffer_type, slice);
+    size_t offset, length;
+    struct rb_io_buffer *buffer = io_buffer_extract_offset_length(self, argc, argv, &offset, &length);
 
-    slice->base = (char*)data->base + offset;
-    slice->size = length;
-
-    // The source should be the root buffer:
-    if (data->source != Qnil)
-        slice->source = data->source;
-    else
-        slice->source = self;
-
-    return instance;
+    return rb_io_buffer_slice(buffer, self, offset, length);
 }
 
-int rb_io_buffer_get_bytes(VALUE self, void **base, size_t *size)
+int
+rb_io_buffer_get_bytes(VALUE self, void **base, size_t *size)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    if (io_buffer_validate(data)) {
-        if (data->base) {
-            *base = data->base;
-            *size = data->size;
+    if (io_buffer_validate(buffer)) {
+        if (buffer->base) {
+            *base = buffer->base;
+            *size = buffer->size;
 
-            return data->flags;
+            return buffer->flags;
         }
     }
 
@@ -1099,20 +1337,21 @@ int rb_io_buffer_get_bytes(VALUE self, void **base, size_t *size)
     return 0;
 }
 
-static void
-io_buffer_get_bytes_for_writing(struct rb_io_buffer *data, void **base, size_t *size)
+static inline void
+io_buffer_get_bytes_for_writing(struct rb_io_buffer *buffer, void **base, size_t *size)
 {
-    if (data->flags & RB_IO_BUFFER_READONLY) {
+    if (buffer->flags & RB_IO_BUFFER_READONLY ||
+        (!NIL_P(buffer->source) && OBJ_FROZEN(buffer->source))) {
         rb_raise(rb_eIOBufferAccessError, "Buffer is not writable!");
     }
 
-    if (!io_buffer_validate(data)) {
+    if (!io_buffer_validate(buffer)) {
         rb_raise(rb_eIOBufferInvalidatedError, "Buffer is invalid!");
     }
 
-    if (data->base) {
-        *base = data->base;
-        *size = data->size;
+    if (buffer->base) {
+        *base = buffer->base;
+        *size = buffer->size;
 
         return;
     }
@@ -1123,22 +1362,22 @@ io_buffer_get_bytes_for_writing(struct rb_io_buffer *data, void **base, size_t *
 void
 rb_io_buffer_get_bytes_for_writing(VALUE self, void **base, size_t *size)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    io_buffer_get_bytes_for_writing(data, base, size);
+    io_buffer_get_bytes_for_writing(buffer, base, size);
 }
 
 static void
-io_buffer_get_bytes_for_reading(struct rb_io_buffer *data, const void **base, size_t *size)
+io_buffer_get_bytes_for_reading(struct rb_io_buffer *buffer, const void **base, size_t *size)
 {
-    if (!io_buffer_validate(data)) {
+    if (!io_buffer_validate(buffer)) {
         rb_raise(rb_eIOBufferInvalidatedError, "Buffer has been invalidated!");
     }
 
-    if (data->base) {
-        *base = data->base;
-        *size = data->size;
+    if (buffer->base) {
+        *base = buffer->base;
+        *size = buffer->size;
 
         return;
     }
@@ -1149,10 +1388,10 @@ io_buffer_get_bytes_for_reading(struct rb_io_buffer *data, const void **base, si
 void
 rb_io_buffer_get_bytes_for_reading(VALUE self, const void **base, size_t *size)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    io_buffer_get_bytes_for_reading(data, base, size);
+    io_buffer_get_bytes_for_reading(buffer, base, size);
 }
 
 /*
@@ -1160,26 +1399,27 @@ rb_io_buffer_get_bytes_for_reading(VALUE self, const void **base, size_t *size)
  *
  *  Transfers ownership to a new buffer, deallocating the current one.
  *
- *     buffer = IO::Buffer.new('test')
- *     other = buffer.transfer
- *     other
- *     #  =>
- *     # #<IO::Buffer 0x00007f136a15f7b0+4 SLICE>
- *     # 0x00000000  74 65 73 74                                     test
- *     buffer
- *     #  =>
- *     # #<IO::Buffer 0x0000000000000000+0 NULL>
- *     buffer.null?
- *     # => true
+ *  Example:
  *
+ *    buffer = IO::Buffer.new('test')
+ *    other = buffer.transfer
+ *    other
+ *    # =>
+ *    # #<IO::Buffer 0x00007f136a15f7b0+4 SLICE>
+ *    # 0x00000000  74 65 73 74                                     test
+ *    buffer
+ *    # =>
+ *    # #<IO::Buffer 0x0000000000000000+0 NULL>
+ *    buffer.null?
+ *    # => true
  */
 VALUE
 rb_io_buffer_transfer(VALUE self)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    if (data->flags & RB_IO_BUFFER_LOCKED) {
+    if (buffer->flags & RB_IO_BUFFER_LOCKED) {
         rb_raise(rb_eIOBufferLockedError, "Cannot transfer ownership of locked buffer!");
     }
 
@@ -1187,91 +1427,96 @@ rb_io_buffer_transfer(VALUE self)
     struct rb_io_buffer *transferred;
     TypedData_Get_Struct(instance, struct rb_io_buffer, &rb_io_buffer_type, transferred);
 
-    *transferred = *data;
-    io_buffer_zero(data);
+    *transferred = *buffer;
+    io_buffer_zero(buffer);
 
     return instance;
 }
 
 static void
-io_buffer_resize_clear(struct rb_io_buffer *data, void* base, size_t size)
+io_buffer_resize_clear(struct rb_io_buffer *buffer, void* base, size_t size)
 {
-    if (size > data->size) {
-        memset((unsigned char*)base+data->size, 0, size - data->size);
+    if (size > buffer->size) {
+        memset((unsigned char*)base+buffer->size, 0, size - buffer->size);
     }
 }
 
 static void
-io_buffer_resize_copy(struct rb_io_buffer *data, size_t size)
+io_buffer_resize_copy(struct rb_io_buffer *buffer, size_t size)
 {
     // Slow path:
     struct rb_io_buffer resized;
     io_buffer_initialize(&resized, NULL, size, io_flags_for_size(size), Qnil);
 
-    if (data->base) {
-        size_t preserve = data->size;
+    if (buffer->base) {
+        size_t preserve = buffer->size;
         if (preserve > size) preserve = size;
-        memcpy(resized.base, data->base, preserve);
+        memcpy(resized.base, buffer->base, preserve);
 
-        io_buffer_resize_clear(data, resized.base, size);
+        io_buffer_resize_clear(buffer, resized.base, size);
     }
 
-    io_buffer_free(data);
-    *data = resized;
+    io_buffer_free(buffer);
+    *buffer = resized;
 }
 
 void
 rb_io_buffer_resize(VALUE self, size_t size)
 {
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    if (data->flags & RB_IO_BUFFER_LOCKED) {
+    if (buffer->flags & RB_IO_BUFFER_LOCKED) {
         rb_raise(rb_eIOBufferLockedError, "Cannot resize locked buffer!");
     }
 
-    if (data->base == NULL) {
-        io_buffer_initialize(data, NULL, size, io_flags_for_size(size), Qnil);
+    if (buffer->base == NULL) {
+        io_buffer_initialize(buffer, NULL, size, io_flags_for_size(size), Qnil);
         return;
     }
 
-    if (data->flags & RB_IO_BUFFER_EXTERNAL) {
+    if (buffer->flags & RB_IO_BUFFER_EXTERNAL) {
         rb_raise(rb_eIOBufferAccessError, "Cannot resize external buffer!");
     }
 
 #if defined(HAVE_MREMAP) && defined(MREMAP_MAYMOVE)
-    if (data->flags & RB_IO_BUFFER_MAPPED) {
-        void *base = mremap(data->base, data->size, size, MREMAP_MAYMOVE);
+    if (buffer->flags & RB_IO_BUFFER_MAPPED) {
+        void *base = mremap(buffer->base, buffer->size, size, MREMAP_MAYMOVE);
 
         if (base == MAP_FAILED) {
             rb_sys_fail("rb_io_buffer_resize:mremap");
         }
 
-        io_buffer_resize_clear(data, base, size);
+        io_buffer_resize_clear(buffer, base, size);
 
-        data->base = base;
-        data->size = size;
+        buffer->base = base;
+        buffer->size = size;
 
         return;
     }
 #endif
 
-    if (data->flags & RB_IO_BUFFER_INTERNAL) {
-        void *base = realloc(data->base, size);
+    if (buffer->flags & RB_IO_BUFFER_INTERNAL) {
+        if (size == 0) {
+            io_buffer_free(buffer);
+            return;
+        }
+
+        void *base = realloc(buffer->base, size);
 
         if (!base) {
             rb_sys_fail("rb_io_buffer_resize:realloc");
         }
 
-        io_buffer_resize_clear(data, base, size);
+        io_buffer_resize_clear(buffer, base, size);
 
-        data->base = base;
-        data->size = size;
+        buffer->base = base;
+        buffer->size = size;
 
         return;
     }
 
-    io_buffer_resize_copy(data, size);
+    io_buffer_resize_copy(buffer, size);
 }
 
 /*
@@ -1285,18 +1530,17 @@ rb_io_buffer_resize(VALUE self, size_t size)
  *    buffer = IO::Buffer.new(4)
  *    buffer.set_string("test", 0)
  *    buffer.resize(8) # resize to 8 bytes
- *    #  =>
+ *    # =>
  *    # #<IO::Buffer 0x0000555f5d1a1630+8 INTERNAL>
  *    # 0x00000000  74 65 73 74 00 00 00 00                         test....
  *
  *  External buffer (created with ::for), and locked buffer
  *  can not be resized.
- *
  */
 static VALUE
 io_buffer_resize(VALUE self, VALUE size)
 {
-    rb_io_buffer_resize(self, NUM2SIZET(size));
+    rb_io_buffer_resize(self, io_buffer_extract_size(size));
 
     return self;
 }
@@ -1306,7 +1550,6 @@ io_buffer_resize(VALUE self, VALUE size)
  *
  * Buffers are compared by size and exact contents of the memory they are
  * referencing using +memcmp+.
- *
  */
 static VALUE
 rb_io_buffer_compare(VALUE self, VALUE other)
@@ -1332,7 +1575,7 @@ static void
 io_buffer_validate_type(size_t size, size_t offset)
 {
     if (offset > size) {
-        rb_raise(rb_eArgError, "Type extends beyond end of buffer!");
+        rb_raise(rb_eArgError, "Type extends beyond end of buffer! (offset=%"PRIdSIZE" > size=%"PRIdSIZE")", offset, size);
     }
 }
 
@@ -1382,8 +1625,8 @@ ruby_swapf64(double value)
     return swap.value;
 }
 
-#define DECLARE_TYPE(name, type, endian, wrap, unwrap, swap) \
-static ID RB_IO_BUFFER_TYPE_##name; \
+#define IO_BUFFER_DECLARE_TYPE(name, type, endian, wrap, unwrap, swap) \
+static ID RB_IO_BUFFER_DATA_TYPE_##name; \
 \
 static VALUE \
 io_buffer_read_##name(const void* base, size_t size, size_t *offset) \
@@ -1404,67 +1647,125 @@ io_buffer_write_##name(const void* base, size_t size, size_t *offset, VALUE _val
     if (endian != RB_IO_BUFFER_HOST_ENDIAN) value = swap(value); \
     memcpy((char*)base + *offset, &value, sizeof(type)); \
     *offset += sizeof(type); \
-}
-
-DECLARE_TYPE(U8, uint8_t, RB_IO_BUFFER_BIG_ENDIAN, RB_UINT2NUM, RB_NUM2UINT, ruby_swap8)
-DECLARE_TYPE(S8, int8_t, RB_IO_BUFFER_BIG_ENDIAN, RB_INT2NUM, RB_NUM2INT, ruby_swap8)
-
-DECLARE_TYPE(u16, uint16_t, RB_IO_BUFFER_LITTLE_ENDIAN, RB_UINT2NUM, RB_NUM2UINT, ruby_swap16)
-DECLARE_TYPE(U16, uint16_t, RB_IO_BUFFER_BIG_ENDIAN, RB_UINT2NUM, RB_NUM2UINT, ruby_swap16)
-DECLARE_TYPE(s16, int16_t, RB_IO_BUFFER_LITTLE_ENDIAN, RB_INT2NUM, RB_NUM2INT, ruby_swap16)
-DECLARE_TYPE(S16, int16_t, RB_IO_BUFFER_BIG_ENDIAN, RB_INT2NUM, RB_NUM2INT, ruby_swap16)
+} \
+\
+enum { \
+    RB_IO_BUFFER_DATA_TYPE_##name##_SIZE = sizeof(type) \
+};
 
-DECLARE_TYPE(u32, uint32_t, RB_IO_BUFFER_LITTLE_ENDIAN, RB_UINT2NUM, RB_NUM2UINT, ruby_swap32)
-DECLARE_TYPE(U32, uint32_t, RB_IO_BUFFER_BIG_ENDIAN, RB_UINT2NUM, RB_NUM2UINT, ruby_swap32)
-DECLARE_TYPE(s32, int32_t, RB_IO_BUFFER_LITTLE_ENDIAN, RB_INT2NUM, RB_NUM2INT, ruby_swap32)
-DECLARE_TYPE(S32, int32_t, RB_IO_BUFFER_BIG_ENDIAN, RB_INT2NUM, RB_NUM2INT, ruby_swap32)
+IO_BUFFER_DECLARE_TYPE(U8, uint8_t, RB_IO_BUFFER_BIG_ENDIAN, RB_UINT2NUM, RB_NUM2UINT, ruby_swap8)
+IO_BUFFER_DECLARE_TYPE(S8, int8_t, RB_IO_BUFFER_BIG_ENDIAN, RB_INT2NUM, RB_NUM2INT, ruby_swap8)
+
+IO_BUFFER_DECLARE_TYPE(u16, uint16_t, RB_IO_BUFFER_LITTLE_ENDIAN, RB_UINT2NUM, RB_NUM2UINT, ruby_swap16)
+IO_BUFFER_DECLARE_TYPE(U16, uint16_t, RB_IO_BUFFER_BIG_ENDIAN, RB_UINT2NUM, RB_NUM2UINT, ruby_swap16)
+IO_BUFFER_DECLARE_TYPE(s16, int16_t, RB_IO_BUFFER_LITTLE_ENDIAN, RB_INT2NUM, RB_NUM2INT, ruby_swap16)
+IO_BUFFER_DECLARE_TYPE(S16, int16_t, RB_IO_BUFFER_BIG_ENDIAN, RB_INT2NUM, RB_NUM2INT, ruby_swap16)
+
+IO_BUFFER_DECLARE_TYPE(u32, uint32_t, RB_IO_BUFFER_LITTLE_ENDIAN, RB_UINT2NUM, RB_NUM2UINT, ruby_swap32)
+IO_BUFFER_DECLARE_TYPE(U32, uint32_t, RB_IO_BUFFER_BIG_ENDIAN, RB_UINT2NUM, RB_NUM2UINT, ruby_swap32)
+IO_BUFFER_DECLARE_TYPE(s32, int32_t, RB_IO_BUFFER_LITTLE_ENDIAN, RB_INT2NUM, RB_NUM2INT, ruby_swap32)
+IO_BUFFER_DECLARE_TYPE(S32, int32_t, RB_IO_BUFFER_BIG_ENDIAN, RB_INT2NUM, RB_NUM2INT, ruby_swap32)
+
+IO_BUFFER_DECLARE_TYPE(u64, uint64_t, RB_IO_BUFFER_LITTLE_ENDIAN, RB_ULL2NUM, RB_NUM2ULL, ruby_swap64)
+IO_BUFFER_DECLARE_TYPE(U64, uint64_t, RB_IO_BUFFER_BIG_ENDIAN, RB_ULL2NUM, RB_NUM2ULL, ruby_swap64)
+IO_BUFFER_DECLARE_TYPE(s64, int64_t, RB_IO_BUFFER_LITTLE_ENDIAN, RB_LL2NUM, RB_NUM2LL, ruby_swap64)
+IO_BUFFER_DECLARE_TYPE(S64, int64_t, RB_IO_BUFFER_BIG_ENDIAN, RB_LL2NUM, RB_NUM2LL, ruby_swap64)
+
+IO_BUFFER_DECLARE_TYPE(f32, float, RB_IO_BUFFER_LITTLE_ENDIAN, DBL2NUM, NUM2DBL, ruby_swapf32)
+IO_BUFFER_DECLARE_TYPE(F32, float, RB_IO_BUFFER_BIG_ENDIAN, DBL2NUM, NUM2DBL, ruby_swapf32)
+IO_BUFFER_DECLARE_TYPE(f64, double, RB_IO_BUFFER_LITTLE_ENDIAN, DBL2NUM, NUM2DBL, ruby_swapf64)
+IO_BUFFER_DECLARE_TYPE(F64, double, RB_IO_BUFFER_BIG_ENDIAN, DBL2NUM, NUM2DBL, ruby_swapf64)
+#undef IO_BUFFER_DECLARE_TYPE
+
+static inline size_t
+io_buffer_buffer_type_size(ID buffer_type)
+{
+#define IO_BUFFER_DATA_TYPE_SIZE(name) if (buffer_type == RB_IO_BUFFER_DATA_TYPE_##name) return RB_IO_BUFFER_DATA_TYPE_##name##_SIZE;
+    IO_BUFFER_DATA_TYPE_SIZE(U8)
+    IO_BUFFER_DATA_TYPE_SIZE(S8)
+    IO_BUFFER_DATA_TYPE_SIZE(u16)
+    IO_BUFFER_DATA_TYPE_SIZE(U16)
+    IO_BUFFER_DATA_TYPE_SIZE(s16)
+    IO_BUFFER_DATA_TYPE_SIZE(S16)
+    IO_BUFFER_DATA_TYPE_SIZE(u32)
+    IO_BUFFER_DATA_TYPE_SIZE(U32)
+    IO_BUFFER_DATA_TYPE_SIZE(s32)
+    IO_BUFFER_DATA_TYPE_SIZE(S32)
+    IO_BUFFER_DATA_TYPE_SIZE(u64)
+    IO_BUFFER_DATA_TYPE_SIZE(U64)
+    IO_BUFFER_DATA_TYPE_SIZE(s64)
+    IO_BUFFER_DATA_TYPE_SIZE(S64)
+    IO_BUFFER_DATA_TYPE_SIZE(f32)
+    IO_BUFFER_DATA_TYPE_SIZE(F32)
+    IO_BUFFER_DATA_TYPE_SIZE(f64)
+    IO_BUFFER_DATA_TYPE_SIZE(F64)
+#undef IO_BUFFER_DATA_TYPE_SIZE
 
-DECLARE_TYPE(u64, uint64_t, RB_IO_BUFFER_LITTLE_ENDIAN, RB_ULL2NUM, RB_NUM2ULL, ruby_swap64)
-DECLARE_TYPE(U64, uint64_t, RB_IO_BUFFER_BIG_ENDIAN, RB_ULL2NUM, RB_NUM2ULL, ruby_swap64)
-DECLARE_TYPE(s64, int64_t, RB_IO_BUFFER_LITTLE_ENDIAN, RB_LL2NUM, RB_NUM2LL, ruby_swap64)
-DECLARE_TYPE(S64, int64_t, RB_IO_BUFFER_BIG_ENDIAN, RB_LL2NUM, RB_NUM2LL, ruby_swap64)
+    rb_raise(rb_eArgError, "Invalid type name!");
+}
 
-DECLARE_TYPE(f32, float, RB_IO_BUFFER_LITTLE_ENDIAN, DBL2NUM, NUM2DBL, ruby_swapf32)
-DECLARE_TYPE(F32, float, RB_IO_BUFFER_BIG_ENDIAN, DBL2NUM, NUM2DBL, ruby_swapf32)
-DECLARE_TYPE(f64, double, RB_IO_BUFFER_LITTLE_ENDIAN, DBL2NUM, NUM2DBL, ruby_swapf64)
-DECLARE_TYPE(F64, double, RB_IO_BUFFER_BIG_ENDIAN, DBL2NUM, NUM2DBL, ruby_swapf64)
-#undef DECLARE_TYPE
+/*
+ *  call-seq:
+ *    size_of(buffer_type) -> byte size
+ *    size_of(array of buffer_type) -> byte size
+ *
+ *  Returns the size of the given buffer type(s) in bytes.
+ *
+ *  Example:
+ *
+ *    IO::Buffer.size_of(:u32) # => 4
+ *    IO::Buffer.size_of([:u32, :u32]) # => 8
+ */
+static VALUE
+io_buffer_size_of(VALUE klass, VALUE buffer_type)
+{
+    if (RB_TYPE_P(buffer_type, T_ARRAY)) {
+        size_t total = 0;
+        for (long i = 0; i < RARRAY_LEN(buffer_type); i++) {
+            total += io_buffer_buffer_type_size(RB_SYM2ID(RARRAY_AREF(buffer_type, i)));
+        }
+        return SIZET2NUM(total);
+    }
+    else {
+        return SIZET2NUM(io_buffer_buffer_type_size(RB_SYM2ID(buffer_type)));
+    }
+}
 
-VALUE
-rb_io_buffer_get_value(const void* base, size_t size, ID type, size_t offset)
+static inline VALUE
+rb_io_buffer_get_value(const void* base, size_t size, ID buffer_type, size_t *offset)
 {
-#define READ_TYPE(name) if (type == RB_IO_BUFFER_TYPE_##name) return io_buffer_read_##name(base, size, &offset);
-    READ_TYPE(U8)
-    READ_TYPE(S8)
+#define IO_BUFFER_GET_VALUE(name) if (buffer_type == RB_IO_BUFFER_DATA_TYPE_##name) return io_buffer_read_##name(base, size, offset);
+    IO_BUFFER_GET_VALUE(U8)
+    IO_BUFFER_GET_VALUE(S8)
 
-    READ_TYPE(u16)
-    READ_TYPE(U16)
-    READ_TYPE(s16)
-    READ_TYPE(S16)
+    IO_BUFFER_GET_VALUE(u16)
+    IO_BUFFER_GET_VALUE(U16)
+    IO_BUFFER_GET_VALUE(s16)
+    IO_BUFFER_GET_VALUE(S16)
 
-    READ_TYPE(u32)
-    READ_TYPE(U32)
-    READ_TYPE(s32)
-    READ_TYPE(S32)
+    IO_BUFFER_GET_VALUE(u32)
+    IO_BUFFER_GET_VALUE(U32)
+    IO_BUFFER_GET_VALUE(s32)
+    IO_BUFFER_GET_VALUE(S32)
 
-    READ_TYPE(u64)
-    READ_TYPE(U64)
-    READ_TYPE(s64)
-    READ_TYPE(S64)
+    IO_BUFFER_GET_VALUE(u64)
+    IO_BUFFER_GET_VALUE(U64)
+    IO_BUFFER_GET_VALUE(s64)
+    IO_BUFFER_GET_VALUE(S64)
 
-    READ_TYPE(f32)
-    READ_TYPE(F32)
-    READ_TYPE(f64)
-    READ_TYPE(F64)
-#undef READ_TYPE
+    IO_BUFFER_GET_VALUE(f32)
+    IO_BUFFER_GET_VALUE(F32)
+    IO_BUFFER_GET_VALUE(f64)
+    IO_BUFFER_GET_VALUE(F64)
+#undef IO_BUFFER_GET_VALUE
 
     rb_raise(rb_eArgError, "Invalid type name!");
 }
 
 /*
- *  call-seq: get_value(type, offset) -> numeric
+ *  call-seq: get_value(buffer_type, offset) -> numeric
  *
- *  Read from buffer a value of +type+ at +offset+. +type+ should be one
+ *  Read from buffer a value of +type+ at +offset+. +buffer_type+ should be one
  *  of symbols:
  *
  *  * +:U8+: unsigned integer, 1 byte
@@ -1486,53 +1787,253 @@ rb_io_buffer_get_value(const void* base, size_t size, ID type, size_t offset)
  *  * +:f64+: double, 8 bytes, little-endian
  *  * +:F64+: double, 8 bytes, big-endian
  *
+ *  A buffer type refers specifically to the type of binary buffer that is stored
+ *  in the buffer. For example, a +:u32+ buffer type is a 32-bit unsigned
+ *  integer in little-endian format.
+ *
  *  Example:
  *
  *    string = [1.5].pack('f')
  *    # => "\x00\x00\xC0?"
  *    IO::Buffer.for(string).get_value(:f32, 0)
  *    # => 1.5
- *
  */
 static VALUE
 io_buffer_get_value(VALUE self, VALUE type, VALUE _offset)
 {
     const void *base;
     size_t size;
-    size_t offset = NUM2SIZET(_offset);
+    size_t offset = io_buffer_extract_offset(_offset);
 
     rb_io_buffer_get_bytes_for_reading(self, &base, &size);
 
-    return rb_io_buffer_get_value(base, size, RB_SYM2ID(type), offset);
+    return rb_io_buffer_get_value(base, size, RB_SYM2ID(type), &offset);
 }
 
-void
-rb_io_buffer_set_value(const void* base, size_t size, ID type, size_t offset, VALUE value)
+/*
+ *  call-seq: get_values(buffer_types, offset) -> array
+ *
+ *  Similar to #get_value, except that it can handle multiple buffer types and
+ *  returns an array of values.
+ *
+ *  Example:
+ *
+ *    string = [1.5, 2.5].pack('ff')
+ *    IO::Buffer.for(string).get_values([:f32, :f32], 0)
+ *    # => [1.5, 2.5]
+ */
+static VALUE
+io_buffer_get_values(VALUE self, VALUE buffer_types, VALUE _offset)
+{
+    size_t offset = io_buffer_extract_offset(_offset);
+
+    const void *base;
+    size_t size;
+    rb_io_buffer_get_bytes_for_reading(self, &base, &size);
+
+    if (!RB_TYPE_P(buffer_types, T_ARRAY)) {
+        rb_raise(rb_eArgError, "Argument buffer_types should be an array!");
+    }
+
+    VALUE array = rb_ary_new_capa(RARRAY_LEN(buffer_types));
+
+    for (long i = 0; i < RARRAY_LEN(buffer_types); i++) {
+        VALUE type = rb_ary_entry(buffer_types, i);
+        VALUE value = rb_io_buffer_get_value(base, size, RB_SYM2ID(type), &offset);
+        rb_ary_push(array, value);
+    }
+
+    return array;
+}
+
+// Extract a count argument, which must be a positive integer.
+// Count is generally considered relative to the number of things.
+static inline size_t
+io_buffer_extract_count(VALUE argument)
+{
+    if (rb_int_negative_p(argument)) {
+        rb_raise(rb_eArgError, "Count can't be negative!");
+    }
+
+    return NUM2SIZET(argument);
+}
+
+static inline void
+io_buffer_extract_offset_count(ID buffer_type, size_t size, int argc, VALUE *argv, size_t *offset, size_t *count)
+{
+    if (argc >= 1) {
+        *offset = io_buffer_extract_offset(argv[0]);
+    }
+    else {
+        *offset = 0;
+    }
+
+    if (argc >= 2) {
+        *count = io_buffer_extract_count(argv[1]);
+    }
+    else {
+        if (*offset > size) {
+            rb_raise(rb_eArgError, "The given offset is bigger than the buffer size!");
+        }
+
+        *count = (size - *offset) / io_buffer_buffer_type_size(buffer_type);
+    }
+}
+
+/*
+ *  call-seq:
+ *    each(buffer_type, [offset, [count]]) {|offset, value| ...} -> self
+ *    each(buffer_type, [offset, [count]]) -> enumerator
+ *
+ *  Iterates over the buffer, yielding each +value+ of +buffer_type+ starting
+ *  from +offset+.
+ *
+ *  If +count+ is given, only +count+ values will be yielded.
+ *
+ *  Example:
+ *
+ *    IO::Buffer.for("Hello World").each(:U8, 2, 2) do |offset, value|
+ *      puts "#{offset}: #{value}"
+ *    end
+ *    # 2: 108
+ *    # 3: 108
+ */
+static VALUE
+io_buffer_each(int argc, VALUE *argv, VALUE self)
 {
-#define WRITE_TYPE(name) if (type == RB_IO_BUFFER_TYPE_##name) {io_buffer_write_##name(base, size, &offset, value); return;}
-    WRITE_TYPE(U8)
-    WRITE_TYPE(S8)
+    RETURN_ENUMERATOR_KW(self, argc, argv, RB_NO_KEYWORDS);
+
+    const void *base;
+    size_t size;
+
+    rb_io_buffer_get_bytes_for_reading(self, &base, &size);
+
+    ID buffer_type;
+    if (argc >= 1) {
+        buffer_type = RB_SYM2ID(argv[0]);
+    }
+    else {
+        buffer_type = RB_IO_BUFFER_DATA_TYPE_U8;
+    }
 
-    WRITE_TYPE(u16)
-    WRITE_TYPE(U16)
-    WRITE_TYPE(s16)
-    WRITE_TYPE(S16)
+    size_t offset, count;
+    io_buffer_extract_offset_count(buffer_type, size, argc-1, argv+1, &offset, &count);
 
-    WRITE_TYPE(u32)
-    WRITE_TYPE(U32)
-    WRITE_TYPE(s32)
-    WRITE_TYPE(S32)
+    for (size_t i = 0; i < count; i++) {
+        size_t current_offset = offset;
+        VALUE value = rb_io_buffer_get_value(base, size, buffer_type, &offset);
+        rb_yield_values(2, SIZET2NUM(current_offset), value);
+    }
 
-    WRITE_TYPE(u64)
-    WRITE_TYPE(U64)
-    WRITE_TYPE(s64)
-    WRITE_TYPE(S64)
+    return self;
+}
 
-    WRITE_TYPE(f32)
-    WRITE_TYPE(F32)
-    WRITE_TYPE(f64)
-    WRITE_TYPE(F64)
-#undef WRITE_TYPE
+/*
+ *  call-seq: values(buffer_type, [offset, [count]]) -> array
+ *
+ *  Returns an array of values of +buffer_type+ starting from +offset+.
+ *
+ *  If +count+ is given, only +count+ values will be returned.
+ *
+ *  Example:
+ *
+ *    IO::Buffer.for("Hello World").values(:U8, 2, 2)
+ *    # => [108, 108]
+ */
+static VALUE
+io_buffer_values(int argc, VALUE *argv, VALUE self)
+{
+    const void *base;
+    size_t size;
+
+    rb_io_buffer_get_bytes_for_reading(self, &base, &size);
+
+    ID buffer_type;
+    if (argc >= 1) {
+        buffer_type = RB_SYM2ID(argv[0]);
+    }
+    else {
+        buffer_type = RB_IO_BUFFER_DATA_TYPE_U8;
+    }
+
+    size_t offset, count;
+    io_buffer_extract_offset_count(buffer_type, size, argc-1, argv+1, &offset, &count);
+
+    VALUE array = rb_ary_new_capa(count);
+
+    for (size_t i = 0; i < count; i++) {
+        VALUE value = rb_io_buffer_get_value(base, size, buffer_type, &offset);
+        rb_ary_push(array, value);
+    }
+
+    return array;
+}
+
+/*
+ *  call-seq:
+ *    each_byte([offset, [count]]) {|offset, byte| ...} -> self
+ *    each_byte([offset, [count]]) -> enumerator
+ *
+ *  Iterates over the buffer, yielding each byte starting from +offset+.
+ *
+ *  If +count+ is given, only +count+ bytes will be yielded.
+ *
+ *  Example:
+ *
+ *    IO::Buffer.for("Hello World").each_byte(2, 2) do |offset, byte|
+ *      puts "#{offset}: #{byte}"
+ *    end
+ *    # 2: 108
+ *    # 3: 108
+ */
+static VALUE
+io_buffer_each_byte(int argc, VALUE *argv, VALUE self)
+{
+    RETURN_ENUMERATOR_KW(self, argc, argv, RB_NO_KEYWORDS);
+
+    const void *base;
+    size_t size;
+
+    rb_io_buffer_get_bytes_for_reading(self, &base, &size);
+
+    size_t offset, count;
+    io_buffer_extract_offset_count(RB_IO_BUFFER_DATA_TYPE_U8, size, argc-1, argv+1, &offset, &count);
+
+    for (size_t i = 0; i < count; i++) {
+        unsigned char *value = (unsigned char *)base + i + offset;
+        rb_yield(RB_INT2FIX(*value));
+    }
+
+    return self;
+}
+
+static inline void
+rb_io_buffer_set_value(const void* base, size_t size, ID buffer_type, size_t *offset, VALUE value)
+{
+#define IO_BUFFER_SET_VALUE(name) if (buffer_type == RB_IO_BUFFER_DATA_TYPE_##name) {io_buffer_write_##name(base, size, offset, value); return;}
+    IO_BUFFER_SET_VALUE(U8);
+    IO_BUFFER_SET_VALUE(S8);
+
+    IO_BUFFER_SET_VALUE(u16);
+    IO_BUFFER_SET_VALUE(U16);
+    IO_BUFFER_SET_VALUE(s16);
+    IO_BUFFER_SET_VALUE(S16);
+
+    IO_BUFFER_SET_VALUE(u32);
+    IO_BUFFER_SET_VALUE(U32);
+    IO_BUFFER_SET_VALUE(s32);
+    IO_BUFFER_SET_VALUE(S32);
+
+    IO_BUFFER_SET_VALUE(u64);
+    IO_BUFFER_SET_VALUE(U64);
+    IO_BUFFER_SET_VALUE(s64);
+    IO_BUFFER_SET_VALUE(S64);
+
+    IO_BUFFER_SET_VALUE(f32);
+    IO_BUFFER_SET_VALUE(F32);
+    IO_BUFFER_SET_VALUE(f64);
+    IO_BUFFER_SET_VALUE(F64);
+#undef IO_BUFFER_SET_VALUE
 
     rb_raise(rb_eArgError, "Invalid type name!");
 }
@@ -1544,13 +2045,15 @@ rb_io_buffer_set_value(const void* base, size_t size, ID type, size_t offset, VA
  *  symbols described in #get_value.
  *
  *    buffer = IO::Buffer.new(8)
- *    #  =>
+ *    # =>
  *    # #<IO::Buffer 0x0000555f5c9a2d50+8 INTERNAL>
  *    # 0x00000000  00 00 00 00 00 00 00 00
+ *
  *    buffer.set_value(:U8, 1, 111)
  *    # => 1
+ *
  *    buffer
- *    #  =>
+ *    # =>
  *    # #<IO::Buffer 0x0000555f5c9a2d50+8 INTERNAL>
  *    # 0x00000000  00 6f 00 00 00 00 00 00                         .o......
  *
@@ -1558,37 +2061,84 @@ rb_io_buffer_set_value(const void* base, size_t size, ID type, size_t offset, VA
  *
  *    buffer = IO::Buffer.new(8)
  *    buffer.set_value(:U32, 0, 2.5)
+ *
  *    buffer
- *    #   =>
- *    #  #<IO::Buffer 0x0000555f5c9a2d50+8 INTERNAL>
- *    #  0x00000000  00 00 00 02 00 00 00 00
- *    #                       ^^ the same as if we'd pass just integer 2
+ *    # =>
+ *    # #<IO::Buffer 0x0000555f5c9a2d50+8 INTERNAL>
+ *    # 0x00000000  00 00 00 02 00 00 00 00
+ *    #                      ^^ the same as if we'd pass just integer 2
  */
 static VALUE
 io_buffer_set_value(VALUE self, VALUE type, VALUE _offset, VALUE value)
 {
     void *base;
     size_t size;
-    size_t offset = NUM2SIZET(_offset);
+    size_t offset = io_buffer_extract_offset(_offset);
+
+    rb_io_buffer_get_bytes_for_writing(self, &base, &size);
+
+    rb_io_buffer_set_value(base, size, RB_SYM2ID(type), &offset, value);
+
+    return SIZET2NUM(offset);
+}
+
+/*
+ *  call-seq: set_values(buffer_types, offset, values) -> offset
+ *
+ *  Write +values+ of +buffer_types+ at +offset+ to the buffer. +buffer_types+
+ *  should be an array of symbols as described in #get_value. +values+ should
+ *  be an array of values to write.
+ *
+ *  Example:
+ *
+ *    buffer = IO::Buffer.new(8)
+ *    buffer.set_values([:U8, :U16], 0, [1, 2])
+ *    buffer
+ *    # =>
+ *    # #<IO::Buffer 0x696f717561746978+8 INTERNAL>
+ *    # 0x00000000  01 00 02 00 00 00 00 00                         ........
+ */
+static VALUE
+io_buffer_set_values(VALUE self, VALUE buffer_types, VALUE _offset, VALUE values)
+{
+    if (!RB_TYPE_P(buffer_types, T_ARRAY)) {
+        rb_raise(rb_eArgError, "Argument buffer_types should be an array!");
+    }
+
+    if (!RB_TYPE_P(values, T_ARRAY)) {
+        rb_raise(rb_eArgError, "Argument values should be an array!");
+    }
+
+    if (RARRAY_LEN(buffer_types) != RARRAY_LEN(values)) {
+        rb_raise(rb_eArgError, "Argument buffer_types and values should have the same length!");
+    }
+
+    size_t offset = io_buffer_extract_offset(_offset);
 
+    void *base;
+    size_t size;
     rb_io_buffer_get_bytes_for_writing(self, &base, &size);
 
-    rb_io_buffer_set_value(base, size, RB_SYM2ID(type), offset, value);
+    for (long i = 0; i < RARRAY_LEN(buffer_types); i++) {
+        VALUE type = rb_ary_entry(buffer_types, i);
+        VALUE value = rb_ary_entry(values, i);
+        rb_io_buffer_set_value(base, size, RB_SYM2ID(type), &offset, value);
+    }
 
     return SIZET2NUM(offset);
 }
 
 static void
-io_buffer_memcpy(struct rb_io_buffer *data, size_t offset, const void *source_base, size_t source_offset, size_t source_size, size_t length)
+io_buffer_memcpy(struct rb_io_buffer *buffer, size_t offset, const void *source_base, size_t source_offset, size_t source_size, size_t length)
 {
     void *base;
     size_t size;
-    io_buffer_get_bytes_for_writing(data, &base, &size);
+    io_buffer_get_bytes_for_writing(buffer, &base, &size);
 
-    io_buffer_validate_range(data, offset, length);
+    io_buffer_validate_range(buffer, offset, length);
 
     if (source_offset + length > source_size) {
-        rb_raise(rb_eArgError, "The computed source range exceeds the size of the source!");
+        rb_raise(rb_eArgError, "The computed source range exceeds the size of the source buffer!");
     }
 
     memcpy((unsigned char*)base+offset, (unsigned char*)source_base+source_offset, length);
@@ -1596,73 +2146,106 @@ io_buffer_memcpy(struct rb_io_buffer *data, size_t offset, const void *source_ba
 
 // (offset, length, source_offset) -> length
 static VALUE
-io_buffer_copy_from(struct rb_io_buffer *data, const void *source_base, size_t source_size, int argc, VALUE *argv)
+io_buffer_copy_from(struct rb_io_buffer *buffer, const void *source_base, size_t source_size, int argc, VALUE *argv)
 {
-    size_t offset;
+    size_t offset = 0;
     size_t length;
     size_t source_offset;
 
     // The offset we copy into the buffer:
     if (argc >= 1) {
-        offset = NUM2SIZET(argv[0]);
-    } else {
-        offset = 0;
+        offset = io_buffer_extract_offset(argv[0]);
     }
 
     // The offset we start from within the string:
     if (argc >= 3) {
-        source_offset = NUM2SIZET(argv[2]);
+        source_offset = io_buffer_extract_offset(argv[2]);
 
         if (source_offset > source_size) {
             rb_raise(rb_eArgError, "The given source offset is bigger than the source itself!");
         }
-    } else {
+    }
+    else {
         source_offset = 0;
     }
 
     // The length we are going to copy:
     if (argc >= 2 && !RB_NIL_P(argv[1])) {
-        length = NUM2SIZET(argv[1]);
-    } else {
+        length = io_buffer_extract_length(argv[1]);
+    }
+    else {
         // Default to the source offset -> source size:
         length = source_size - source_offset;
     }
 
-    io_buffer_memcpy(data, offset, source_base, source_offset, source_size, length);
+    io_buffer_memcpy(buffer, offset, source_base, source_offset, source_size, length);
 
     return SIZET2NUM(length);
 }
 
 /*
  *  call-seq:
+ *    dup -> io_buffer
+ *    clone -> io_buffer
+ *
+ *  Make an internal copy of the source buffer. Updates to the copy will not
+ *  affect the source buffer.
+ *
+ *    source = IO::Buffer.for("Hello World")
+ *    # =>
+ *    # #<IO::Buffer 0x00007fd598466830+11 EXTERNAL READONLY SLICE>
+ *    # 0x00000000  48 65 6c 6c 6f 20 57 6f 72 6c 64                Hello World
+ *    buffer = source.dup
+ *    # =>
+ *    # #<IO::Buffer 0x0000558cbec03320+11 INTERNAL>
+ *    # 0x00000000  48 65 6c 6c 6f 20 57 6f 72 6c 64                Hello World
+ */
+static VALUE
+rb_io_buffer_initialize_copy(VALUE self, VALUE source)
+{
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
+
+    const void *source_base;
+    size_t source_size;
+
+    rb_io_buffer_get_bytes_for_reading(source, &source_base, &source_size);
+
+    io_buffer_initialize(buffer, NULL, source_size, io_flags_for_size(source_size), Qnil);
+
+    return io_buffer_copy_from(buffer, source_base, source_size, 0, NULL);
+}
+
+/*
+ *  call-seq:
  *    copy(source, [offset, [length, [source_offset]]]) -> size
  *
- *  Efficiently copy data from a source IO::Buffer into the buffer,
+ *  Efficiently copy buffer from a source IO::Buffer into the buffer,
  *  at +offset+ using +memcpy+. For copying String instances, see #set_string.
  *
  *    buffer = IO::Buffer.new(32)
- *    #  =>
+ *    # =>
  *    # #<IO::Buffer 0x0000555f5ca22520+32 INTERNAL>
  *    # 0x00000000  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
  *    # 0x00000010  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................  *
  *
  *    buffer.copy(IO::Buffer.for("test"), 8)
- *    # => 4 -- size of data copied
+ *    # => 4 -- size of buffer copied
  *    buffer
- *    #  =>
+ *    # =>
  *    # #<IO::Buffer 0x0000555f5cf8fe40+32 INTERNAL>
  *    # 0x00000000  00 00 00 00 00 00 00 00 74 65 73 74 00 00 00 00 ........test....
  *    # 0x00000010  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ *
  *
- *  #copy can be used to put data into strings associated with buffer:
+ *  #copy can be used to put buffer into strings associated with buffer:
  *
- *    string= "data:    "
- *    # => "data:    "
- *    buffer = IO::Buffer.for(str)
+ *    string= "buffer:    "
+ *    # => "buffer:    "
+ *    buffer = IO::Buffer.for(string)
  *    buffer.copy(IO::Buffer.for("test"), 5)
  *    # => 4
  *    string
- *    # => "data:test"
+ *    # => "buffer:test"
  *
  *  Attempt to copy into a read-only buffer will fail:
  *
@@ -1680,21 +2263,20 @@ io_buffer_copy_from(struct rb_io_buffer *data, const void *source_base, size_t s
  *    File.read('test.txt')
  *    # => "boom"
  *
- *  Attempt to copy the data which will need place outside of buffer's
+ *  Attempt to copy the buffer which will need place outside of buffer's
  *  bounds will fail:
  *
  *    buffer = IO::Buffer.new(2)
  *    buffer.copy(IO::Buffer.for('test'), 0)
- *    # in `copy': Specified offset+length exceeds source size! (ArgumentError)
- *
+ *    # in `copy': Specified offset+length is bigger than the buffer size! (ArgumentError)
  */
 static VALUE
 io_buffer_copy(int argc, VALUE *argv, VALUE self)
 {
-    if (argc < 1 || argc > 4) rb_error_arity(argc, 1, 4);
+    rb_check_arity(argc, 1, 4);
 
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
     VALUE source = argv[0];
     const void *source_base;
@@ -1702,7 +2284,7 @@ io_buffer_copy(int argc, VALUE *argv, VALUE self)
 
     rb_io_buffer_get_bytes_for_reading(source, &source_base, &source_size);
 
-    return io_buffer_copy_from(data, source_base, source_size, argc-1, argv+1);
+    return io_buffer_copy_from(buffer, source_base, source_size, argc-1, argv+1);
 }
 
 /*
@@ -1711,46 +2293,35 @@ io_buffer_copy(int argc, VALUE *argv, VALUE self)
  *  Read a chunk or all of the buffer into a string, in the specified
  *  +encoding+. If no encoding is provided +Encoding::BINARY+ is used.
  *
- *     buffer = IO::Buffer.for('test')
- *     buffer.get_string
- *     # => "test"
- *     buffer.get_string(2)
- *     # => "st"
- *     buffer.get_string(2, 1)
- *     # => "s"
- *
+ *    buffer = IO::Buffer.for('test')
+ *    buffer.get_string
+ *    # => "test"
+ *    buffer.get_string(2)
+ *    # => "st"
+ *    buffer.get_string(2, 1)
+ *    # => "s"
  */
 static VALUE
 io_buffer_get_string(int argc, VALUE *argv, VALUE self)
 {
-    if (argc > 3) rb_error_arity(argc, 0, 3);
+    rb_check_arity(argc, 0, 3);
 
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    size_t offset, length;
+    struct rb_io_buffer *buffer = io_buffer_extract_offset_length(self, argc, argv, &offset, &length);
 
     const void *base;
     size_t size;
-    io_buffer_get_bytes_for_reading(data, &base, &size);
-
-    size_t offset = 0;
-    size_t length = size;
-    rb_encoding *encoding = rb_ascii8bit_encoding();
-
-    if (argc >= 1) {
-        offset = NUM2SIZET(argv[0]);
-    }
-
-    if (argc >= 2 && !RB_NIL_P(argv[1])) {
-        length = NUM2SIZET(argv[1]);
-    } else {
-        length = size - offset;
-    }
+    io_buffer_get_bytes_for_reading(buffer, &base, &size);
 
+    rb_encoding *encoding;
     if (argc >= 3) {
         encoding = rb_find_encoding(argv[2]);
     }
+    else {
+        encoding = rb_ascii8bit_encoding();
+    }
 
-    io_buffer_validate_range(data, offset, length);
+    io_buffer_validate_range(buffer, offset, length);
 
     return rb_enc_str_new((const char*)base + offset, length, encoding);
 }
@@ -1758,7 +2329,7 @@ io_buffer_get_string(int argc, VALUE *argv, VALUE self)
 /*
  *  call-seq: set_string(string, [offset, [length, [source_offset]]]) -> size
  *
- *  Efficiently copy data from a source String into the buffer,
+ *  Efficiently copy buffer from a source String into the buffer,
  *  at +offset+ using +memcpy+.
  *
  *    buf = IO::Buffer.new(8)
@@ -1766,7 +2337,7 @@ io_buffer_get_string(int argc, VALUE *argv, VALUE self)
  *    # #<IO::Buffer 0x0000557412714a20+8 INTERNAL>
  *    # 0x00000000  00 00 00 00 00 00 00 00                         ........
  *
- *    # set data starting from offset 1, take 2 bytes starting from string's
+ *    # set buffer starting from offset 1, take 2 bytes starting from string's
  *    # second
  *    buf.set_string('test', 1, 2, 1)
  *    # => 2
@@ -1781,30 +2352,30 @@ io_buffer_get_string(int argc, VALUE *argv, VALUE self)
 static VALUE
 io_buffer_set_string(int argc, VALUE *argv, VALUE self)
 {
-    if (argc < 1 || argc > 4) rb_error_arity(argc, 1, 4);
+    rb_check_arity(argc, 1, 4);
 
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
     VALUE string = rb_str_to_str(argv[0]);
 
     const void *source_base = RSTRING_PTR(string);
     size_t source_size = RSTRING_LEN(string);
 
-    return io_buffer_copy_from(data, source_base, source_size, argc-1, argv+1);
+    return io_buffer_copy_from(buffer, source_base, source_size, argc-1, argv+1);
 }
 
 void
 rb_io_buffer_clear(VALUE self, uint8_t value, size_t offset, size_t length)
 {
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
+
     void *base;
     size_t size;
+    io_buffer_get_bytes_for_writing(buffer, &base, &size);
 
-    rb_io_buffer_get_bytes_for_writing(self, &base, &size);
-
-    if (offset + length > size) {
-        rb_raise(rb_eArgError, "The given offset + length out of bounds!");
-    }
+    io_buffer_validate_range(buffer, offset, length);
 
     memset((char*)base + offset, value, length);
 }
@@ -1839,40 +2410,28 @@ rb_io_buffer_clear(VALUE self, uint8_t value, size_t offset, size_t length)
  *    # =>
  *    #   <IO::Buffer 0x00007fca40087c38+4 SLICE>
  *    #   0x00000000  01 02 02 02         ....
- *
  */
 static VALUE
 io_buffer_clear(int argc, VALUE *argv, VALUE self)
 {
-    if (argc > 3) rb_error_arity(argc, 0, 3);
-
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    rb_check_arity(argc, 0, 3);
 
     uint8_t value = 0;
     if (argc >= 1) {
         value = NUM2UINT(argv[0]);
     }
 
-    size_t offset = 0;
-    if (argc >= 2) {
-        offset = NUM2SIZET(argv[1]);
-    }
-
-    size_t length;
-    if (argc >= 3) {
-        length = NUM2SIZET(argv[2]);
-    } else {
-        length = data->size - offset;
-    }
+    size_t offset, length;
+    io_buffer_extract_offset_length(self, argc-1, argv+1, &offset, &length);
 
     rb_io_buffer_clear(self, value, offset, length);
 
     return self;
 }
 
-static
-size_t io_buffer_default_size(size_t page_size) {
+static size_t
+io_buffer_default_size(size_t page_size)
+{
     // Platform agnostic default size, based on empirical performance observation:
     const size_t platform_agnostic_default_size = 64*1024;
 
@@ -1895,170 +2454,843 @@ size_t io_buffer_default_size(size_t page_size) {
     return platform_agnostic_default_size;
 }
 
-VALUE
-rb_io_buffer_read(VALUE self, VALUE io, size_t length)
+struct io_buffer_blocking_region_argument {
+    struct rb_io_buffer *buffer;
+    rb_blocking_function_t *function;
+    void *data;
+    int descriptor;
+};
+
+static VALUE
+io_buffer_blocking_region_begin(VALUE _argument)
 {
-    VALUE scheduler = rb_fiber_scheduler_current();
-    if (scheduler != Qnil) {
-        VALUE result = rb_fiber_scheduler_io_read(scheduler, io, self, length);
+    struct io_buffer_blocking_region_argument *argument = (void*)_argument;
 
-        if (result != Qundef) {
-            return result;
-        }
-    }
+    return rb_thread_io_blocking_region(argument->function, argument->data, argument->descriptor);
+}
 
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+static VALUE
+io_buffer_blocking_region_ensure(VALUE _argument)
+{
+    struct io_buffer_blocking_region_argument *argument = (void*)_argument;
 
-    io_buffer_validate_range(data, 0, length);
+    io_buffer_unlock(argument->buffer);
 
-    int descriptor = rb_io_descriptor(io);
+    return Qnil;
+}
 
-    void * base;
-    size_t size;
-    io_buffer_get_bytes_for_writing(data, &base, &size);
+static VALUE
+io_buffer_blocking_region(struct rb_io_buffer *buffer, rb_blocking_function_t *function, void *data, int descriptor)
+{
+    struct io_buffer_blocking_region_argument argument = {
+        .buffer = buffer,
+        .function = function,
+        .data = data,
+        .descriptor = descriptor,
+    };
 
-    ssize_t result = read(descriptor, base, size);
+    // If the buffer is already locked, we can skip the ensure (unlock):
+    if (buffer->flags & RB_IO_BUFFER_LOCKED) {
+        return io_buffer_blocking_region_begin((VALUE)&argument);
+    }
+    else {
+        // The buffer should be locked for the duration of the blocking region:
+        io_buffer_lock(buffer);
 
-    return rb_fiber_scheduler_io_result(result, errno);
+        return rb_ensure(io_buffer_blocking_region_begin, (VALUE)&argument, io_buffer_blocking_region_ensure, (VALUE)&argument);
+    }
 }
 
+struct io_buffer_read_internal_argument {
+    int descriptor;
+
+    // The base pointer to read from:
+    char *base;
+    // The size of the buffer:
+    size_t size;
+
+    // The minimum number of bytes to read:
+    size_t length;
+};
+
 static VALUE
-io_buffer_read(VALUE self, VALUE io, VALUE length)
+io_buffer_read_internal(void *_argument)
 {
-    return rb_io_buffer_read(self, io, RB_NUM2SIZE(length));
+    size_t total = 0;
+    struct io_buffer_read_internal_argument *argument = _argument;
+
+    while (true) {
+        ssize_t result = read(argument->descriptor, argument->base, argument->size);
+
+        if (result < 0) {
+            return rb_fiber_scheduler_io_result(result, errno);
+        }
+        else if (result == 0) {
+            return rb_fiber_scheduler_io_result(total, 0);
+        }
+        else {
+            total += result;
+
+            if (total >= argument->length) {
+                return rb_fiber_scheduler_io_result(total, 0);
+            }
+
+            argument->base = argument->base + result;
+            argument->size = argument->size - result;
+        }
+    }
 }
 
 VALUE
-rb_io_buffer_pread(VALUE self, VALUE io, size_t length, off_t offset)
+rb_io_buffer_read(VALUE self, VALUE io, size_t length, size_t offset)
 {
     VALUE scheduler = rb_fiber_scheduler_current();
     if (scheduler != Qnil) {
-        VALUE result = rb_fiber_scheduler_io_pread(scheduler, io, self, length, offset);
+        VALUE result = rb_fiber_scheduler_io_read(scheduler, io, self, length, offset);
 
-        if (result != Qundef) {
+        if (!UNDEF_P(result)) {
             return result;
         }
     }
 
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    io_buffer_validate_range(data, 0, length);
+    io_buffer_validate_range(buffer, offset, length);
 
     int descriptor = rb_io_descriptor(io);
 
     void * base;
     size_t size;
-    io_buffer_get_bytes_for_writing(data, &base, &size);
+    io_buffer_get_bytes_for_writing(buffer, &base, &size);
+
+    base = (unsigned char*)base + offset;
+    size = size - offset;
+
+    struct io_buffer_read_internal_argument argument = {
+        .descriptor = descriptor,
+        .base = base,
+        .size = size,
+        .length = length,
+    };
+
+    return io_buffer_blocking_region(buffer, io_buffer_read_internal, &argument, descriptor);
+}
+
+/*
+ *  call-seq: read(io, [length, [offset]]) -> read length or -errno
+ *
+ *  Read at least +length+ bytes from the +io+, into the buffer starting at
+ *  +offset+. If an error occurs, return <tt>-errno</tt>.
+ *
+ *  If +length+ is not given or +nil+, it defaults to the size of the buffer
+ *  minus the offset, i.e. the entire buffer.
+ *
+ *  If +length+ is zero, exactly one <tt>read</tt> operation will occur.
+ *
+ *  If +offset+ is not given, it defaults to zero, i.e. the beginning of the
+ *  buffer.
+ *
+ *    IO::Buffer.for('test') do |buffer|
+ *      p buffer
+ *      # =>
+ *      # <IO::Buffer 0x00007fca40087c38+4 SLICE>
+ *      # 0x00000000  74 65 73 74         test
+ *      buffer.read(File.open('/dev/urandom', 'rb'), 2)
+ *      p buffer
+ *      # =>
+ *      # <IO::Buffer 0x00007f3bc65f2a58+4 EXTERNAL SLICE>
+ *      # 0x00000000  05 35 73 74         .5st
+ *    end
+ */
+static VALUE
+io_buffer_read(int argc, VALUE *argv, VALUE self)
+{
+    rb_check_arity(argc, 1, 3);
+
+    VALUE io = argv[0];
+
+    size_t length, offset;
+    io_buffer_extract_length_offset(self, argc-1, argv+1, &length, &offset);
+
+    return rb_io_buffer_read(self, io, length, offset);
+}
+
+struct io_buffer_pread_internal_argument {
+    int descriptor;
+    void *base;
+    size_t size;
+    off_t offset;
+};
+
+static VALUE
+io_buffer_pread_internal(void *_argument)
+{
+    struct io_buffer_pread_internal_argument *argument = _argument;
 
 #if defined(HAVE_PREAD)
-    ssize_t result = pread(descriptor, base, size, offset);
+    ssize_t result = pread(argument->descriptor, argument->base, argument->size, argument->offset);
 #else
-    // This emulation is not thread safe, but the GVL means it's unlikely to be a problem.
-    off_t current_offset = lseek(descriptor, 0, SEEK_CUR);
-    if (current_offset == (off_t)-1)
+    // This emulation is not thread safe.
+    rb_off_t offset = lseek(argument->descriptor, 0, SEEK_CUR);
+    if (offset == (rb_off_t)-1)
         return rb_fiber_scheduler_io_result(-1, errno);
 
-    if (lseek(descriptor, offset, SEEK_SET) == (off_t)-1)
+    if (lseek(argument->descriptor, argument->offset, SEEK_SET) == (rb_off_t)-1)
         return rb_fiber_scheduler_io_result(-1, errno);
 
-    ssize_t result = read(descriptor, base, size);
+    ssize_t result = read(argument->descriptor, argument->base, argument->size);
 
-    if (lseek(descriptor, current_offset, SEEK_SET) == (off_t)-1)
+    if (lseek(argument->descriptor, offset, SEEK_SET) == (rb_off_t)-1)
         return rb_fiber_scheduler_io_result(-1, errno);
 #endif
 
     return rb_fiber_scheduler_io_result(result, errno);
 }
 
-static VALUE
-io_buffer_pread(VALUE self, VALUE io, VALUE length, VALUE offset)
-{
-    return rb_io_buffer_pread(self, io, RB_NUM2SIZE(length), NUM2OFFT(offset));
-}
-
 VALUE
-rb_io_buffer_write(VALUE self, VALUE io, size_t length)
+rb_io_buffer_pread(VALUE self, VALUE io, rb_off_t from, size_t length, size_t offset)
 {
     VALUE scheduler = rb_fiber_scheduler_current();
     if (scheduler != Qnil) {
-        VALUE result = rb_fiber_scheduler_io_write(scheduler, io, self, length);
+        VALUE result = rb_fiber_scheduler_io_pread(scheduler, io, from, self, length, offset);
 
-        if (result != Qundef) {
+        if (!UNDEF_P(result)) {
             return result;
         }
     }
 
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    io_buffer_validate_range(data, 0, length);
+    io_buffer_validate_range(buffer, offset, length);
 
     int descriptor = rb_io_descriptor(io);
 
-    const void * base;
+    void * base;
     size_t size;
-    io_buffer_get_bytes_for_reading(data, &base, &size);
+    io_buffer_get_bytes_for_writing(buffer, &base, &size);
 
-    ssize_t result = write(descriptor, base, length);
+    struct io_buffer_pread_internal_argument argument = {
+        .descriptor = descriptor,
 
-    return rb_fiber_scheduler_io_result(result, errno);
+        // Move the base pointer to the offset:
+        .base = (unsigned char*)base + offset,
+
+        // And the size to the length of buffer we want to read:
+        .size = length,
+
+        // From the offset in the file we want to read from:
+        .offset = from,
+    };
+
+    return io_buffer_blocking_region(buffer, io_buffer_pread_internal, &argument, descriptor);
 }
 
+/*
+ *  call-seq: pread(io, from, length, [offset]) -> read length or -errno
+ *
+ *  Read at most +length+ bytes from +io+ into the buffer, starting at
+ *  +from+, and put it in buffer starting from specified +offset+.
+ *  If an error occurs, return <tt>-errno</tt>.
+ *
+ *  If +offset+ is not given, put it at the beginning of the buffer.
+ *
+ *  Example:
+ *
+ *    IO::Buffer.for('test') do |buffer|
+ *      p buffer
+ *      # =>
+ *      # <IO::Buffer 0x00007fca40087c38+4 SLICE>
+ *      # 0x00000000  74 65 73 74         test
+ *
+ *      # take 2 bytes from the beginning of urandom,
+ *      # put them in buffer starting from position 2
+ *      buffer.pread(File.open('/dev/urandom', 'rb'), 0, 2, 2)
+ *      p buffer
+ *      # =>
+ *      # <IO::Buffer 0x00007f3bc65f2a58+4 EXTERNAL SLICE>
+ *      # 0x00000000  05 35 73 74         te.5
+ *    end
+ */
+static VALUE
+io_buffer_pread(int argc, VALUE *argv, VALUE self)
+{
+    rb_check_arity(argc, 2, 4);
+
+    VALUE io = argv[0];
+    rb_off_t from = NUM2OFFT(argv[1]);
+
+    size_t length, offset;
+    io_buffer_extract_length_offset(self, argc-2, argv+2, &length, &offset);
+
+    return rb_io_buffer_pread(self, io, from, length, offset);
+}
+
+struct io_buffer_write_internal_argument {
+    int descriptor;
+
+    // The base pointer to write from:
+    const char *base;
+    // The size of the buffer:
+    size_t size;
+
+    // The minimum length to write:
+    size_t length;
+};
+
 static VALUE
-io_buffer_write(VALUE self, VALUE io, VALUE length)
+io_buffer_write_internal(void *_argument)
 {
-    return rb_io_buffer_write(self, io, RB_NUM2SIZE(length));
+    size_t total = 0;
+    struct io_buffer_write_internal_argument *argument = _argument;
+
+    while (true) {
+        ssize_t result = write(argument->descriptor, argument->base, argument->size);
+
+        if (result < 0) {
+            return rb_fiber_scheduler_io_result(result, errno);
+        }
+        else if (result == 0) {
+            return rb_fiber_scheduler_io_result(total, 0);
+        }
+        else {
+            total += result;
+
+            if (total >= argument->length) {
+                return rb_fiber_scheduler_io_result(total, 0);
+            }
+
+            argument->base = argument->base + result;
+            argument->size = argument->size - result;
+        }
+    }
 }
 
 VALUE
-rb_io_buffer_pwrite(VALUE self, VALUE io, size_t length, off_t offset)
+rb_io_buffer_write(VALUE self, VALUE io, size_t length, size_t offset)
 {
     VALUE scheduler = rb_fiber_scheduler_current();
     if (scheduler != Qnil) {
-        VALUE result = rb_fiber_scheduler_io_pwrite(scheduler, io, self, length, OFFT2NUM(offset));
+        VALUE result = rb_fiber_scheduler_io_write(scheduler, io, self, length, offset);
 
-        if (result != Qundef) {
+        if (!UNDEF_P(result)) {
             return result;
         }
     }
 
-    struct rb_io_buffer *data = NULL;
-    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, data);
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
 
-    io_buffer_validate_range(data, 0, length);
+    io_buffer_validate_range(buffer, offset, length);
 
     int descriptor = rb_io_descriptor(io);
 
     const void * base;
     size_t size;
-    io_buffer_get_bytes_for_reading(data, &base, &size);
+    io_buffer_get_bytes_for_reading(buffer, &base, &size);
+
+    base = (unsigned char*)base + offset;
+    size = size - offset;
+
+    struct io_buffer_write_internal_argument argument = {
+        .descriptor = descriptor,
+        .base = base,
+        .size = size,
+        .length = length,
+    };
+
+    return io_buffer_blocking_region(buffer, io_buffer_write_internal, &argument, descriptor);
+}
+
+/*
+ *  call-seq: write(io, [length, [offset]]) -> written length or -errno
+ *
+ *  Write at least +length+ bytes from the buffer starting at +offset+, into the +io+.
+ *  If an error occurs, return <tt>-errno</tt>.
+ *
+ *  If +length+ is not given or +nil+, it defaults to the size of the buffer
+ *  minus the offset, i.e. the entire buffer.
+ *
+ *  If +length+ is zero, exactly one <tt>write</tt> operation will occur.
+ *
+ *  If +offset+ is not given, it defaults to zero, i.e. the beginning of the
+ *  buffer.
+ *
+ *    out = File.open('output.txt', 'wb')
+ *    IO::Buffer.for('1234567').write(out, 3)
+ *
+ *  This leads to +123+ being written into <tt>output.txt</tt>
+ */
+static VALUE
+io_buffer_write(int argc, VALUE *argv, VALUE self)
+{
+    rb_check_arity(argc, 1, 3);
+
+    VALUE io = argv[0];
+
+    size_t length, offset;
+    io_buffer_extract_length_offset(self, argc-1, argv+1, &length, &offset);
+
+    return rb_io_buffer_write(self, io, length, offset);
+}
+
+struct io_buffer_pwrite_internal_argument {
+    int descriptor;
+    const void *base;
+    size_t size;
+    off_t offset;
+};
+
+static VALUE
+io_buffer_pwrite_internal(void *_argument)
+{
+    struct io_buffer_pwrite_internal_argument *argument = _argument;
 
 #if defined(HAVE_PWRITE)
-    ssize_t result = pwrite(descriptor, base, length, offset);
+    ssize_t result = pwrite(argument->descriptor, argument->base, argument->size, argument->offset);
 #else
-    // This emulation is not thread safe, but the GVL means it's unlikely to be a problem.
-    off_t current_offset = lseek(descriptor, 0, SEEK_CUR);
-    if (current_offset == (off_t)-1)
+    // This emulation is not thread safe.
+    rb_off_t offset = lseek(argument->descriptor, 0, SEEK_CUR);
+    if (offset == (rb_off_t)-1)
         return rb_fiber_scheduler_io_result(-1, errno);
 
-    if (lseek(descriptor, offset, SEEK_SET) == (off_t)-1)
+    if (lseek(argument->descriptor, argument->offset, SEEK_SET) == (rb_off_t)-1)
         return rb_fiber_scheduler_io_result(-1, errno);
 
-    ssize_t result = write(descriptor, base, length);
+    ssize_t result = write(argument->descriptor, argument->base, argument->size);
 
-    if (lseek(descriptor, current_offset, SEEK_SET) == (off_t)-1)
+    if (lseek(argument->descriptor, offset, SEEK_SET) == (rb_off_t)-1)
         return rb_fiber_scheduler_io_result(-1, errno);
 #endif
 
     return rb_fiber_scheduler_io_result(result, errno);
 }
 
+VALUE
+rb_io_buffer_pwrite(VALUE self, VALUE io, rb_off_t from, size_t length, size_t offset)
+{
+    VALUE scheduler = rb_fiber_scheduler_current();
+    if (scheduler != Qnil) {
+        VALUE result = rb_fiber_scheduler_io_pwrite(scheduler, io, from, self, length, offset);
+
+        if (!UNDEF_P(result)) {
+            return result;
+        }
+    }
+
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
+
+    io_buffer_validate_range(buffer, offset, length);
+
+    int descriptor = rb_io_descriptor(io);
+
+    const void * base;
+    size_t size;
+    io_buffer_get_bytes_for_reading(buffer, &base, &size);
+
+    struct io_buffer_pwrite_internal_argument argument = {
+        .descriptor = descriptor,
+
+        // Move the base pointer to the offset:
+        .base = (unsigned char *)base + offset,
+
+        // And the size to the length of buffer we want to read:
+        .size = length,
+
+        // And the offset in the file we want to write from:
+        .offset = from,
+    };
+
+    return io_buffer_blocking_region(buffer, io_buffer_pwrite_internal, &argument, descriptor);
+}
+
+/*
+ *  call-seq: pwrite(io, from, length, [offset]) -> written length or -errno
+ *
+ *  Writes +length+ bytes from buffer into +io+, starting at
+ *  +offset+ in the buffer. If an error occurs, return <tt>-errno</tt>.
+ *
+ *  If +offset+ is not given, the bytes are taken from the beginning of the
+ *  buffer. If the +offset+ is given and is beyond the end of the file, the
+ *  gap will be filled with null (0 value) bytes.
+ *
+ *    out = File.open('output.txt', File::RDWR) # open for read/write, no truncation
+ *    IO::Buffer.for('1234567').pwrite(out, 2, 3, 1)
+ *
+ *  This leads to +234+ (3 bytes, starting from position 1) being written into
+ *  <tt>output.txt</tt>, starting from file position 2.
+ */
 static VALUE
-io_buffer_pwrite(VALUE self, VALUE io, VALUE length, VALUE offset)
+io_buffer_pwrite(int argc, VALUE *argv, VALUE self)
+{
+    rb_check_arity(argc, 2, 4);
+
+    VALUE io = argv[0];
+    rb_off_t from = NUM2OFFT(argv[1]);
+
+    size_t length, offset;
+    io_buffer_extract_length_offset(self, argc-2, argv+2, &length, &offset);
+
+    return rb_io_buffer_pwrite(self, io, from, length, offset);
+}
+
+static inline void
+io_buffer_check_mask(const struct rb_io_buffer *buffer)
 {
-    return rb_io_buffer_pwrite(self, io, RB_NUM2SIZE(length), NUM2OFFT(offset));
+    if (buffer->size == 0)
+        rb_raise(rb_eIOBufferMaskError, "Zero-length mask given!");
+}
+
+static void
+memory_and(unsigned char * restrict output, unsigned char * restrict base, size_t size, unsigned char * restrict mask, size_t mask_size)
+{
+    for (size_t offset = 0; offset < size; offset += 1) {
+        output[offset] = base[offset] & mask[offset % mask_size];
+    }
+}
+
+/*
+ *  call-seq:
+ *    source & mask -> io_buffer
+ *
+ *  Generate a new buffer the same size as the source by applying the binary AND
+ *  operation to the source, using the mask, repeating as necessary.
+ *
+ *    IO::Buffer.for("1234567890") & IO::Buffer.for("\xFF\x00\x00\xFF")
+ *    # =>
+ *    # #<IO::Buffer 0x00005589b2758480+4 INTERNAL>
+ *    # 0x00000000  31 00 00 34 35 00 00 38 39 00                   1..45..89.
+ */
+static VALUE
+io_buffer_and(VALUE self, VALUE mask)
+{
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
+
+    struct rb_io_buffer *mask_buffer = NULL;
+    TypedData_Get_Struct(mask, struct rb_io_buffer, &rb_io_buffer_type, mask_buffer);
+
+    io_buffer_check_mask(mask_buffer);
+
+    VALUE output = rb_io_buffer_new(NULL, buffer->size, io_flags_for_size(buffer->size));
+    struct rb_io_buffer *output_buffer = NULL;
+    TypedData_Get_Struct(output, struct rb_io_buffer, &rb_io_buffer_type, output_buffer);
+
+    memory_and(output_buffer->base, buffer->base, buffer->size, mask_buffer->base, mask_buffer->size);
+
+    return output;
+}
+
+static void
+memory_or(unsigned char * restrict output, unsigned char * restrict base, size_t size, unsigned char * restrict mask, size_t mask_size)
+{
+    for (size_t offset = 0; offset < size; offset += 1) {
+        output[offset] = base[offset] | mask[offset % mask_size];
+    }
+}
+
+/*
+ *  call-seq:
+ *    source | mask -> io_buffer
+ *
+ *  Generate a new buffer the same size as the source by applying the binary OR
+ *  operation to the source, using the mask, repeating as necessary.
+ *
+ *    IO::Buffer.for("1234567890") | IO::Buffer.for("\xFF\x00\x00\xFF")
+ *    # =>
+ *    # #<IO::Buffer 0x0000561785ae3480+10 INTERNAL>
+ *    # 0x00000000  ff 32 33 ff ff 36 37 ff ff 30                   .23..67..0
+ */
+static VALUE
+io_buffer_or(VALUE self, VALUE mask)
+{
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
+
+    struct rb_io_buffer *mask_buffer = NULL;
+    TypedData_Get_Struct(mask, struct rb_io_buffer, &rb_io_buffer_type, mask_buffer);
+
+    io_buffer_check_mask(mask_buffer);
+
+    VALUE output = rb_io_buffer_new(NULL, buffer->size, io_flags_for_size(buffer->size));
+    struct rb_io_buffer *output_buffer = NULL;
+    TypedData_Get_Struct(output, struct rb_io_buffer, &rb_io_buffer_type, output_buffer);
+
+    memory_or(output_buffer->base, buffer->base, buffer->size, mask_buffer->base, mask_buffer->size);
+
+    return output;
+}
+
+static void
+memory_xor(unsigned char * restrict output, unsigned char * restrict base, size_t size, unsigned char * restrict mask, size_t mask_size)
+{
+    for (size_t offset = 0; offset < size; offset += 1) {
+        output[offset] = base[offset] ^ mask[offset % mask_size];
+    }
+}
+
+/*
+ *  call-seq:
+ *    source ^ mask -> io_buffer
+ *
+ *  Generate a new buffer the same size as the source by applying the binary XOR
+ *  operation to the source, using the mask, repeating as necessary.
+ *
+ *    IO::Buffer.for("1234567890") ^ IO::Buffer.for("\xFF\x00\x00\xFF")
+ *    # =>
+ *    # #<IO::Buffer 0x000055a2d5d10480+10 INTERNAL>
+ *    # 0x00000000  ce 32 33 cb ca 36 37 c7 c6 30                   .23..67..0
+ */
+static VALUE
+io_buffer_xor(VALUE self, VALUE mask)
+{
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
+
+    struct rb_io_buffer *mask_buffer = NULL;
+    TypedData_Get_Struct(mask, struct rb_io_buffer, &rb_io_buffer_type, mask_buffer);
+
+    io_buffer_check_mask(mask_buffer);
+
+    VALUE output = rb_io_buffer_new(NULL, buffer->size, io_flags_for_size(buffer->size));
+    struct rb_io_buffer *output_buffer = NULL;
+    TypedData_Get_Struct(output, struct rb_io_buffer, &rb_io_buffer_type, output_buffer);
+
+    memory_xor(output_buffer->base, buffer->base, buffer->size, mask_buffer->base, mask_buffer->size);
+
+    return output;
+}
+
+static void
+memory_not(unsigned char * restrict output, unsigned char * restrict base, size_t size)
+{
+    for (size_t offset = 0; offset < size; offset += 1) {
+        output[offset] = ~base[offset];
+    }
+}
+
+/*
+ *  call-seq:
+ *    ~source -> io_buffer
+ *
+ *  Generate a new buffer the same size as the source by applying the binary NOT
+ *  operation to the source.
+ *
+ *    ~IO::Buffer.for("1234567890")
+ *    # =>
+ *    # #<IO::Buffer 0x000055a5ac42f120+10 INTERNAL>
+ *    # 0x00000000  ce cd cc cb ca c9 c8 c7 c6 cf                   ..........
+ */
+static VALUE
+io_buffer_not(VALUE self)
+{
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
+
+    VALUE output = rb_io_buffer_new(NULL, buffer->size, io_flags_for_size(buffer->size));
+    struct rb_io_buffer *output_buffer = NULL;
+    TypedData_Get_Struct(output, struct rb_io_buffer, &rb_io_buffer_type, output_buffer);
+
+    memory_not(output_buffer->base, buffer->base, buffer->size);
+
+    return output;
+}
+
+static inline int
+io_buffer_overlaps(const struct rb_io_buffer *a, const struct rb_io_buffer *b)
+{
+    if (a->base > b->base) {
+        return io_buffer_overlaps(b, a);
+    }
+
+    return (b->base >= a->base) && (b->base <= (void*)((unsigned char *)a->base + a->size));
+}
+
+static inline void
+io_buffer_check_overlaps(struct rb_io_buffer *a, struct rb_io_buffer *b)
+{
+    if (io_buffer_overlaps(a, b))
+        rb_raise(rb_eIOBufferMaskError, "Mask overlaps source buffer!");
+}
+
+static void
+memory_and_inplace(unsigned char * restrict base, size_t size, unsigned char * restrict mask, size_t mask_size)
+{
+    for (size_t offset = 0; offset < size; offset += 1) {
+        base[offset] &= mask[offset % mask_size];
+    }
+}
+
+/*
+ *  call-seq:
+ *    source.and!(mask) -> io_buffer
+ *
+ *  Modify the source buffer in place by applying the binary AND
+ *  operation to the source, using the mask, repeating as necessary.
+ *
+ *    source = IO::Buffer.for("1234567890").dup # Make a read/write copy.
+ *    # =>
+ *    # #<IO::Buffer 0x000056307a0d0c20+10 INTERNAL>
+ *    # 0x00000000  31 32 33 34 35 36 37 38 39 30                   1234567890
+ *
+ *    source.and!(IO::Buffer.for("\xFF\x00\x00\xFF"))
+ *    # =>
+ *    # #<IO::Buffer 0x000056307a0d0c20+10 INTERNAL>
+ *    # 0x00000000  31 00 00 34 35 00 00 38 39 00                   1..45..89.
+ */
+static VALUE
+io_buffer_and_inplace(VALUE self, VALUE mask)
+{
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
+
+    struct rb_io_buffer *mask_buffer = NULL;
+    TypedData_Get_Struct(mask, struct rb_io_buffer, &rb_io_buffer_type, mask_buffer);
+
+    io_buffer_check_mask(mask_buffer);
+    io_buffer_check_overlaps(buffer, mask_buffer);
+
+    void *base;
+    size_t size;
+    io_buffer_get_bytes_for_writing(buffer, &base, &size);
+
+    memory_and_inplace(base, size, mask_buffer->base, mask_buffer->size);
+
+    return self;
+}
+
+static void
+memory_or_inplace(unsigned char * restrict base, size_t size, unsigned char * restrict mask, size_t mask_size)
+{
+    for (size_t offset = 0; offset < size; offset += 1) {
+        base[offset] |= mask[offset % mask_size];
+    }
+}
+
+/*
+ *  call-seq:
+ *    source.or!(mask) -> io_buffer
+ *
+ *  Modify the source buffer in place by applying the binary OR
+ *  operation to the source, using the mask, repeating as necessary.
+ *
+ *    source = IO::Buffer.for("1234567890").dup # Make a read/write copy.
+ *    # =>
+ *    # #<IO::Buffer 0x000056307a272350+10 INTERNAL>
+ *    # 0x00000000  31 32 33 34 35 36 37 38 39 30                   1234567890
+ *
+ *    source.or!(IO::Buffer.for("\xFF\x00\x00\xFF"))
+ *    # =>
+ *    # #<IO::Buffer 0x000056307a272350+10 INTERNAL>
+ *    # 0x00000000  ff 32 33 ff ff 36 37 ff ff 30                   .23..67..0
+ */
+static VALUE
+io_buffer_or_inplace(VALUE self, VALUE mask)
+{
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
+
+    struct rb_io_buffer *mask_buffer = NULL;
+    TypedData_Get_Struct(mask, struct rb_io_buffer, &rb_io_buffer_type, mask_buffer);
+
+    io_buffer_check_mask(mask_buffer);
+    io_buffer_check_overlaps(buffer, mask_buffer);
+
+    void *base;
+    size_t size;
+    io_buffer_get_bytes_for_writing(buffer, &base, &size);
+
+    memory_or_inplace(base, size, mask_buffer->base, mask_buffer->size);
+
+    return self;
+}
+
+static void
+memory_xor_inplace(unsigned char * restrict base, size_t size, unsigned char * restrict mask, size_t mask_size)
+{
+    for (size_t offset = 0; offset < size; offset += 1) {
+        base[offset] ^= mask[offset % mask_size];
+    }
+}
+
+/*
+ *  call-seq:
+ *    source.xor!(mask) -> io_buffer
+ *
+ *  Modify the source buffer in place by applying the binary XOR
+ *  operation to the source, using the mask, repeating as necessary.
+ *
+ *    source = IO::Buffer.for("1234567890").dup # Make a read/write copy.
+ *    # =>
+ *    # #<IO::Buffer 0x000056307a25b3e0+10 INTERNAL>
+ *    # 0x00000000  31 32 33 34 35 36 37 38 39 30                   1234567890
+ *
+ *    source.xor!(IO::Buffer.for("\xFF\x00\x00\xFF"))
+ *    # =>
+ *    # #<IO::Buffer 0x000056307a25b3e0+10 INTERNAL>
+ *    # 0x00000000  ce 32 33 cb ca 36 37 c7 c6 30                   .23..67..0
+ */
+static VALUE
+io_buffer_xor_inplace(VALUE self, VALUE mask)
+{
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
+
+    struct rb_io_buffer *mask_buffer = NULL;
+    TypedData_Get_Struct(mask, struct rb_io_buffer, &rb_io_buffer_type, mask_buffer);
+
+    io_buffer_check_mask(mask_buffer);
+    io_buffer_check_overlaps(buffer, mask_buffer);
+
+    void *base;
+    size_t size;
+    io_buffer_get_bytes_for_writing(buffer, &base, &size);
+
+    memory_xor_inplace(base, size, mask_buffer->base, mask_buffer->size);
+
+    return self;
+}
+
+static void
+memory_not_inplace(unsigned char * restrict base, size_t size)
+{
+    for (size_t offset = 0; offset < size; offset += 1) {
+        base[offset] = ~base[offset];
+    }
+}
+
+/*
+ *  call-seq:
+ *    source.not! -> io_buffer
+ *
+ *  Modify the source buffer in place by applying the binary NOT
+ *  operation to the source.
+ *
+ *    source = IO::Buffer.for("1234567890").dup # Make a read/write copy.
+ *    # =>
+ *    # #<IO::Buffer 0x000056307a33a450+10 INTERNAL>
+ *    # 0x00000000  31 32 33 34 35 36 37 38 39 30                   1234567890
+ *
+ *    source.not!
+ *    # =>
+ *    # #<IO::Buffer 0x000056307a33a450+10 INTERNAL>
+ *    # 0x00000000  ce cd cc cb ca c9 c8 c7 c6 cf                   ..........
+ */
+static VALUE
+io_buffer_not_inplace(VALUE self)
+{
+    struct rb_io_buffer *buffer = NULL;
+    TypedData_Get_Struct(self, struct rb_io_buffer, &rb_io_buffer_type, buffer);
+
+    void *base;
+    size_t size;
+    io_buffer_get_bytes_for_writing(buffer, &base, &size);
+
+    memory_not_inplace(base, size);
+
+    return self;
 }
 
 /*
@@ -2067,8 +3299,8 @@ io_buffer_pwrite(VALUE self, VALUE io, VALUE length, VALUE offset)
  *  IO::Buffer is a low-level efficient buffer for input/output. There are three
  *  ways of using buffer:
  *
- *  * Create an empty buffer with ::new, fill it with data using #copy or
- *    #set_value, #set_string, get data with #get_string;
+ *  * Create an empty buffer with ::new, fill it with buffer using #copy or
+ *    #set_value, #set_string, get buffer with #get_string;
  *  * Create a buffer mapped to some string with ::for, then it could be used
  *    both for reading with #get_string or #get_value, and writing (writing will
  *    change the source string, too);
@@ -2086,11 +3318,11 @@ io_buffer_pwrite(VALUE self, VALUE io, VALUE length, VALUE offset)
  *  Empty buffer:
  *
  *    buffer = IO::Buffer.new(8)  # create empty 8-byte buffer
- *    #  =>
+ *    # =>
  *    # #<IO::Buffer 0x0000555f5d1a5c50+8 INTERNAL>
  *    # ...
  *    buffer
- *    #  =>
+ *    # =>
  *    # <IO::Buffer 0x0000555f5d156ab0+8 INTERNAL>
  *    # 0x00000000  00 00 00 00 00 00 00 00
  *    buffer.set_string('test', 2) # put there bytes of the "test" string, starting from offset 2
@@ -2100,22 +3332,22 @@ io_buffer_pwrite(VALUE self, VALUE io, VALUE length, VALUE offset)
  *
  *  \Buffer from string:
  *
- *    string = 'data'
- *    buffer = IO::Buffer.for(str)
- *    #  =>
+ *    string = 'buffer'
+ *    buffer = IO::Buffer.for(string)
+ *    # =>
  *    # #<IO::Buffer 0x00007f3f02be9b18+4 SLICE>
  *    # ...
  *    buffer
- *    #  =>
+ *    # =>
  *    # #<IO::Buffer 0x00007f3f02be9b18+4 SLICE>
- *    # 0x00000000  64 61 74 61                                     data
+ *    # 0x00000000  64 61 74 61                                     buffer
  *
  *    buffer.get_string(2)  # read content starting from offset 2
  *    # => "ta"
  *    buffer.set_string('---', 1) # write content, starting from offset 1
  *    # => 3
  *    buffer
- *    #  =>
+ *    # =>
  *    # #<IO::Buffer 0x00007f3f02be9b18+4 SLICE>
  *    # 0x00000000  64 2d 2d 2d                                     d---
  *    string  # original string changed, too
@@ -2123,10 +3355,10 @@ io_buffer_pwrite(VALUE self, VALUE io, VALUE length, VALUE offset)
  *
  *  \Buffer from file:
  *
- *    File.write('test.txt', 'test data')
+ *    File.write('test.txt', 'test buffer')
  *    # => 9
  *    buffer = IO::Buffer.map(File.open('test.txt'))
- *    #  =>
+ *    # =>
  *    # #<IO::Buffer 0x00007f3f0768c000+9 MAPPED IMMUTABLE>
  *    # ...
  *    buffer.get_string(5, 2) # read 2 bytes, starting from offset 5
@@ -2140,7 +3372,7 @@ io_buffer_pwrite(VALUE self, VALUE io, VALUE length, VALUE offset)
  *    buffer.set_string('---', 1)
  *    # => 3 -- bytes written
  *    File.read('test.txt')
- *    # => "t--- data"
+ *    # => "t--- buffer"
  *
  *  <b>The class is experimental and the interface is subject to change.</b>
  */
@@ -2152,6 +3384,7 @@ Init_IO_Buffer(void)
     rb_eIOBufferAllocationError = rb_define_class_under(rb_cIOBuffer, "AllocationError", rb_eRuntimeError);
     rb_eIOBufferAccessError = rb_define_class_under(rb_cIOBuffer, "AccessError", rb_eRuntimeError);
     rb_eIOBufferInvalidatedError = rb_define_class_under(rb_cIOBuffer, "InvalidatedError", rb_eRuntimeError);
+    rb_eIOBufferMaskError = rb_define_class_under(rb_cIOBuffer, "MaskError", rb_eArgError);
 
     rb_define_alloc_func(rb_cIOBuffer, rb_io_buffer_type_allocate);
     rb_define_singleton_method(rb_cIOBuffer, "for", rb_io_buffer_type_for, 1);
@@ -2174,6 +3407,7 @@ Init_IO_Buffer(void)
 
     // General use:
     rb_define_method(rb_cIOBuffer, "initialize", rb_io_buffer_initialize, -1);
+    rb_define_method(rb_cIOBuffer, "initialize_copy", rb_io_buffer_initialize_copy, 1);
     rb_define_method(rb_cIOBuffer, "inspect", rb_io_buffer_inspect, 0);
     rb_define_method(rb_cIOBuffer, "hexdump", rb_io_buffer_hexdump, 0);
     rb_define_method(rb_cIOBuffer, "to_s", rb_io_buffer_to_s, 0);
@@ -2187,6 +3421,7 @@ Init_IO_Buffer(void)
     rb_define_const(rb_cIOBuffer, "EXTERNAL", RB_INT2NUM(RB_IO_BUFFER_EXTERNAL));
     rb_define_const(rb_cIOBuffer, "INTERNAL", RB_INT2NUM(RB_IO_BUFFER_INTERNAL));
     rb_define_const(rb_cIOBuffer, "MAPPED", RB_INT2NUM(RB_IO_BUFFER_MAPPED));
+    rb_define_const(rb_cIOBuffer, "SHARED", RB_INT2NUM(RB_IO_BUFFER_SHARED));
     rb_define_const(rb_cIOBuffer, "LOCKED", RB_INT2NUM(RB_IO_BUFFER_LOCKED));
     rb_define_const(rb_cIOBuffer, "PRIVATE", RB_INT2NUM(RB_IO_BUFFER_PRIVATE));
     rb_define_const(rb_cIOBuffer, "READONLY", RB_INT2NUM(RB_IO_BUFFER_READONLY));
@@ -2202,6 +3437,7 @@ Init_IO_Buffer(void)
     rb_define_method(rb_cIOBuffer, "external?", rb_io_buffer_external_p, 0);
     rb_define_method(rb_cIOBuffer, "internal?", rb_io_buffer_internal_p, 0);
     rb_define_method(rb_cIOBuffer, "mapped?", rb_io_buffer_mapped_p, 0);
+    rb_define_method(rb_cIOBuffer, "shared?", rb_io_buffer_shared_p, 0);
     rb_define_method(rb_cIOBuffer, "locked?", rb_io_buffer_locked_p, 0);
     rb_define_method(rb_cIOBuffer, "readonly?", io_buffer_readonly_p, 0);
 
@@ -2211,7 +3447,7 @@ Init_IO_Buffer(void)
     rb_define_method(rb_cIOBuffer, "locked", rb_io_buffer_locked, 0);
 
     // Manipulation:
-    rb_define_method(rb_cIOBuffer, "slice", rb_io_buffer_slice, 2);
+    rb_define_method(rb_cIOBuffer, "slice", io_buffer_slice, -1);
     rb_define_method(rb_cIOBuffer, "<=>", rb_io_buffer_compare, 1);
     rb_define_method(rb_cIOBuffer, "resize", io_buffer_resize, 1);
     rb_define_method(rb_cIOBuffer, "clear", io_buffer_clear, -1);
@@ -2219,26 +3455,61 @@ Init_IO_Buffer(void)
 
     rb_include_module(rb_cIOBuffer, rb_mComparable);
 
-#define DEFINE_TYPE(name) RB_IO_BUFFER_TYPE_##name = rb_intern_const(#name)
-    DEFINE_TYPE(U8); DEFINE_TYPE(S8);
-    DEFINE_TYPE(u16); DEFINE_TYPE(U16); DEFINE_TYPE(s16); DEFINE_TYPE(S16);
-    DEFINE_TYPE(u32); DEFINE_TYPE(U32); DEFINE_TYPE(s32); DEFINE_TYPE(S32);
-    DEFINE_TYPE(u64); DEFINE_TYPE(U64); DEFINE_TYPE(s64); DEFINE_TYPE(S64);
-    DEFINE_TYPE(f32); DEFINE_TYPE(F32); DEFINE_TYPE(f64); DEFINE_TYPE(F64);
-#undef DEFINE_TYPE
+#define IO_BUFFER_DEFINE_DATA_TYPE(name) RB_IO_BUFFER_DATA_TYPE_##name = rb_intern_const(#name)
+    IO_BUFFER_DEFINE_DATA_TYPE(U8);
+    IO_BUFFER_DEFINE_DATA_TYPE(S8);
+
+    IO_BUFFER_DEFINE_DATA_TYPE(u16);
+    IO_BUFFER_DEFINE_DATA_TYPE(U16);
+    IO_BUFFER_DEFINE_DATA_TYPE(s16);
+    IO_BUFFER_DEFINE_DATA_TYPE(S16);
+
+    IO_BUFFER_DEFINE_DATA_TYPE(u32);
+    IO_BUFFER_DEFINE_DATA_TYPE(U32);
+    IO_BUFFER_DEFINE_DATA_TYPE(s32);
+    IO_BUFFER_DEFINE_DATA_TYPE(S32);
+
+    IO_BUFFER_DEFINE_DATA_TYPE(u64);
+    IO_BUFFER_DEFINE_DATA_TYPE(U64);
+    IO_BUFFER_DEFINE_DATA_TYPE(s64);
+    IO_BUFFER_DEFINE_DATA_TYPE(S64);
+
+    IO_BUFFER_DEFINE_DATA_TYPE(f32);
+    IO_BUFFER_DEFINE_DATA_TYPE(F32);
+    IO_BUFFER_DEFINE_DATA_TYPE(f64);
+    IO_BUFFER_DEFINE_DATA_TYPE(F64);
+#undef IO_BUFFER_DEFINE_DATA_TYPE
+
+    rb_define_singleton_method(rb_cIOBuffer, "size_of", io_buffer_size_of, 1);
 
     // Data access:
     rb_define_method(rb_cIOBuffer, "get_value", io_buffer_get_value, 2);
+    rb_define_method(rb_cIOBuffer, "get_values", io_buffer_get_values, 2);
+    rb_define_method(rb_cIOBuffer, "each", io_buffer_each, -1);
+    rb_define_method(rb_cIOBuffer, "values", io_buffer_values, -1);
+    rb_define_method(rb_cIOBuffer, "each_byte", io_buffer_each_byte, -1);
     rb_define_method(rb_cIOBuffer, "set_value", io_buffer_set_value, 3);
+    rb_define_method(rb_cIOBuffer, "set_values", io_buffer_set_values, 3);
 
     rb_define_method(rb_cIOBuffer, "copy", io_buffer_copy, -1);
 
     rb_define_method(rb_cIOBuffer, "get_string", io_buffer_get_string, -1);
     rb_define_method(rb_cIOBuffer, "set_string", io_buffer_set_string, -1);
 
+    // Binary buffer manipulations:
+    rb_define_method(rb_cIOBuffer, "&", io_buffer_and, 1);
+    rb_define_method(rb_cIOBuffer, "|", io_buffer_or, 1);
+    rb_define_method(rb_cIOBuffer, "^", io_buffer_xor, 1);
+    rb_define_method(rb_cIOBuffer, "~", io_buffer_not, 0);
+
+    rb_define_method(rb_cIOBuffer, "and!", io_buffer_and_inplace, 1);
+    rb_define_method(rb_cIOBuffer, "or!", io_buffer_or_inplace, 1);
+    rb_define_method(rb_cIOBuffer, "xor!", io_buffer_xor_inplace, 1);
+    rb_define_method(rb_cIOBuffer, "not!", io_buffer_not_inplace, 0);
+
     // IO operations:
-    rb_define_method(rb_cIOBuffer, "read", io_buffer_read, 2);
-    rb_define_method(rb_cIOBuffer, "pread", io_buffer_pread, 3);
-    rb_define_method(rb_cIOBuffer, "write", io_buffer_write, 2);
-    rb_define_method(rb_cIOBuffer, "pwrite", io_buffer_pwrite, 3);
+    rb_define_method(rb_cIOBuffer, "read", io_buffer_read, -1);
+    rb_define_method(rb_cIOBuffer, "pread", io_buffer_pread, -1);
+    rb_define_method(rb_cIOBuffer, "write", io_buffer_write, -1);
+    rb_define_method(rb_cIOBuffer, "pwrite", io_buffer_pwrite, -1);
 }
diff --git a/iseq.c b/iseq.c
index 129d6d3b2c..d17ce486c5 100644
--- a/iseq.c
+++ b/iseq.c
@@ -60,19 +60,19 @@ static inline VALUE
 obj_resurrect(VALUE obj)
 {
     if (hidden_obj_p(obj)) {
-	switch (BUILTIN_TYPE(obj)) {
-	  case T_STRING:
-	    obj = rb_str_resurrect(obj);
-	    break;
-	  case T_ARRAY:
-	    obj = rb_ary_resurrect(obj);
-	    break;
+        switch (BUILTIN_TYPE(obj)) {
+          case T_STRING:
+            obj = rb_str_resurrect(obj);
+            break;
+          case T_ARRAY:
+            obj = rb_ary_resurrect(obj);
+            break;
           case T_HASH:
             obj = rb_hash_resurrect(obj);
             break;
           default:
-	    break;
-	}
+            break;
+        }
     }
     return obj;
 }
@@ -93,77 +93,69 @@ static void
 compile_data_free(struct iseq_compile_data *compile_data)
 {
     if (compile_data) {
-	free_arena(compile_data->node.storage_head);
-	free_arena(compile_data->insn.storage_head);
-	if (compile_data->ivar_cache_table) {
-	    rb_id_table_free(compile_data->ivar_cache_table);
-	}
-	ruby_xfree(compile_data);
+        free_arena(compile_data->node.storage_head);
+        free_arena(compile_data->insn.storage_head);
+        if (compile_data->ivar_cache_table) {
+            rb_id_table_free(compile_data->ivar_cache_table);
+        }
+        ruby_xfree(compile_data);
     }
 }
 
-struct iseq_clear_ic_references_data {
-    IC ic;
-};
-
-// This iterator is used to walk through the instructions and clean any
-// references to ICs that are contained within this ISEQ out of the VM's
-// constant cache table. It passes around a struct that holds the current IC
-// we're looking for, which can be NULL (if we haven't hit an opt_getinlinecache
-// instruction yet) or set to an IC (if we've hit an opt_getinlinecache and
-// haven't yet hit the associated opt_setinlinecache).
-static bool
-iseq_clear_ic_references_i(VALUE *code, VALUE insn, size_t index, void *data)
+static void
+remove_from_constant_cache(ID id, IC ic)
 {
-    struct iseq_clear_ic_references_data *ic_data = (struct iseq_clear_ic_references_data *) data;
+    rb_vm_t *vm = GET_VM();
+    VALUE lookup_result;
+    st_data_t ic_data = (st_data_t)ic;
 
-    switch (insn) {
-      case BIN(opt_getinlinecache): {
-        RUBY_ASSERT_ALWAYS(ic_data->ic == NULL);
+    if (rb_id_table_lookup(vm->constant_cache, id, &lookup_result)) {
+        st_table *ics = (st_table *)lookup_result;
+        st_delete(ics, &ic_data, NULL);
 
-        ic_data->ic = (IC) code[index + 2];
-        return true;
-      }
-      case BIN(getconstant): {
-        if (ic_data->ic != NULL) {
-            ID id = (ID) code[index + 1];
-            rb_vm_t *vm = GET_VM();
-            VALUE lookup_result;
-
-            if (rb_id_table_lookup(vm->constant_cache, id, &lookup_result)) {
-                st_table *ics = (st_table *)lookup_result;
-                st_data_t ic = (st_data_t)ic_data->ic;
-                st_delete(ics, &ic, NULL);
-
-                if (ics->num_entries == 0) {
-                    rb_id_table_delete(vm->constant_cache, id);
-                    st_free_table(ics);
-                }
-            }
+        if (ics->num_entries == 0 &&
+                // See comment in vm_track_constant_cache on why we need this check
+                id != vm->inserting_constant_cache_id) {
+            rb_id_table_delete(vm->constant_cache, id);
+            st_free_table(ics);
         }
-
-        return true;
-      }
-      case BIN(opt_setinlinecache): {
-        RUBY_ASSERT_ALWAYS(ic_data->ic != NULL);
-
-        ic_data->ic = NULL;
-        return true;
-      }
-      default:
-        return true;
     }
 }
 
 // When an ISEQ is being freed, all of its associated ICs are going to go away
-// as well. Because of this, we need to walk through the ISEQ, find any
-// opt_getinlinecache calls, and clear out the VM's constant cache of associated
-// ICs.
+// as well. Because of this, we need to iterate over the ICs, and clear them
+// from the VM's constant cache.
 static void
 iseq_clear_ic_references(const rb_iseq_t *iseq)
 {
-    struct iseq_clear_ic_references_data data = { .ic = NULL };
-    rb_iseq_each(iseq, 0, iseq_clear_ic_references_i, (void *) &data);
+    // In some cases (when there is a compilation error), we end up with
+    // ic_size greater than 0, but no allocated is_entries buffer.
+    // If there's no is_entries buffer to loop through, return early.
+    // [Bug #19173]
+    if (!ISEQ_BODY(iseq)->is_entries) {
+        return;
+    }
+
+    for (unsigned int ic_idx = 0; ic_idx < ISEQ_BODY(iseq)->ic_size; ic_idx++) {
+        IC ic = &ISEQ_IS_IC_ENTRY(ISEQ_BODY(iseq), ic_idx);
+
+        // Iterate over the IC's constant path's segments and clean any references to
+        // the ICs out of the VM's constant cache table.
+        const ID *segments = ic->segments;
+
+        // It's possible that segments is NULL if we overallocated an IC but
+        // optimizations removed the instruction using it
+        if (segments == NULL)
+            continue;
+
+        for (int i = 0; segments[i]; i++) {
+            ID id = segments[i];
+            if (id == idNULL) continue;
+            remove_from_constant_cache(id, ic);
+        }
+
+        ruby_xfree((void *)segments);
+    }
 }
 
 void
@@ -174,31 +166,40 @@ rb_iseq_free(const rb_iseq_t *iseq)
     if (iseq && ISEQ_BODY(iseq)) {
         iseq_clear_ic_references(iseq);
         struct rb_iseq_constant_body *const body = ISEQ_BODY(iseq);
-	mjit_free_iseq(iseq); /* Notify MJIT */
-        rb_yjit_iseq_free(body);
-	ruby_xfree((void *)body->iseq_encoded);
-	ruby_xfree((void *)body->insns_info.body);
-	if (body->insns_info.positions) ruby_xfree((void *)body->insns_info.positions);
+        mjit_free_iseq(iseq); /* Notify MJIT */
+#if USE_YJIT
+        rb_yjit_iseq_free(body->yjit_payload);
+#endif
+        ruby_xfree((void *)body->iseq_encoded);
+        ruby_xfree((void *)body->insns_info.body);
+        if (body->insns_info.positions) ruby_xfree((void *)body->insns_info.positions);
 #if VM_INSN_INFO_TABLE_IMPL == 2
-	if (body->insns_info.succ_index_table) ruby_xfree(body->insns_info.succ_index_table);
+        if (body->insns_info.succ_index_table) ruby_xfree(body->insns_info.succ_index_table);
 #endif
         if (LIKELY(body->local_table != rb_iseq_shared_exc_local_tbl))
             ruby_xfree((void *)body->local_table);
-	ruby_xfree((void *)body->is_entries);
+        ruby_xfree((void *)body->is_entries);
 
         if (body->call_data) {
             ruby_xfree(body->call_data);
-	}
-	ruby_xfree((void *)body->catch_table);
-	ruby_xfree((void *)body->param.opt_table);
-
-	if (body->param.keyword != NULL) {
-	    ruby_xfree((void *)body->param.keyword->default_values);
-	    ruby_xfree((void *)body->param.keyword);
-	}
-	compile_data_free(ISEQ_COMPILE_DATA(iseq));
+        }
+        ruby_xfree((void *)body->catch_table);
+        ruby_xfree((void *)body->param.opt_table);
+        if (ISEQ_MBITS_BUFLEN(body->iseq_size) > 1 && body->mark_bits.list) {
+            ruby_xfree((void *)body->mark_bits.list);
+        }
+
+        ruby_xfree(body->variable.original_iseq);
+
+        if (body->param.keyword != NULL) {
+            if (body->param.keyword->table != &body->local_table[body->param.keyword->bits_start - body->param.keyword->num])
+                ruby_xfree((void *)body->param.keyword->table);
+            ruby_xfree((void *)body->param.keyword->default_values);
+            ruby_xfree((void *)body->param.keyword);
+        }
+        compile_data_free(ISEQ_COMPILE_DATA(iseq));
         if (body->outer_variables) rb_id_table_free(body->outer_variables);
-	ruby_xfree(body);
+        ruby_xfree(body);
     }
 
     if (iseq && ISEQ_EXECUTABLE_P(iseq) && iseq->aux.exec.local_hooks) {
@@ -208,106 +209,27 @@ rb_iseq_free(const rb_iseq_t *iseq)
     RUBY_FREE_LEAVE("iseq");
 }
 
-#if OPT_DIRECT_THREADED_CODE || OPT_CALL_THREADED_CODE
-static VALUE
-rb_vm_insn_addr2insn2(const void *addr)
-{
-    return (VALUE)rb_vm_insn_addr2insn(addr);
-}
-#endif
-
-static VALUE
-rb_vm_insn_null_translator(const void *addr)
-{
-    return (VALUE)addr;
-}
-
-// The translator for OPT_DIRECT_THREADED_CODE and OPT_CALL_THREADED_CODE does
-// some normalization to always return the non-trace version of instructions. To
-// mirror that behavior in token-threaded environments, we normalize in this
-// translator by also returning non-trace opcodes.
-static VALUE
-rb_vm_insn_normalizing_translator(const void *addr)
-{
-    VALUE opcode = (VALUE)addr;
-    VALUE trace_opcode_threshold = (VM_INSTRUCTION_SIZE / 2);
-
-    if (opcode >= trace_opcode_threshold) {
-        return opcode - trace_opcode_threshold;
-    }
-    return opcode;
-}
-
 typedef VALUE iseq_value_itr_t(void *ctx, VALUE obj);
-typedef VALUE rb_vm_insns_translator_t(const void *addr);
 
-static int
-iseq_extract_values(VALUE *code, size_t pos, iseq_value_itr_t * func, void *data, rb_vm_insns_translator_t * translator)
-{
-    VALUE insn = translator((void *)code[pos]);
-    int len = insn_len(insn);
-    int op_no;
-    const char *types = insn_op_types(insn);
-
-    for (op_no = 0; types[op_no]; op_no++) {
-	char type = types[op_no];
-	switch (type) {
-          case TS_CDHASH:
-          case TS_ISEQ:
-          case TS_VALUE:
-            {
-              VALUE op = code[pos + op_no + 1];
-              if (!SPECIAL_CONST_P(op)) {
-                  VALUE newop = func(data, op);
-                  if (newop != op) {
-                      code[pos + op_no + 1] = newop;
-                  }
-              }
-            }
-            break;
-          case TS_IC:
-            {
-                IC ic = (IC)code[pos + op_no + 1];
-                if (ic->entry) {
-                    VALUE nv = func(data, (VALUE)ic->entry);
-                    if ((VALUE)ic->entry != nv) {
-                        ic->entry = (void *)nv;
-                    }
-                }
+static inline void
+iseq_scan_bits(unsigned int page, iseq_bits_t bits, VALUE *code, iseq_value_itr_t *func, void *data)
+{
+    unsigned int offset;
+    unsigned int page_offset = (page * ISEQ_MBITS_BITLENGTH);
+
+    while (bits) {
+        offset = ntz_intptr(bits);
+        VALUE op = code[page_offset + offset];
+        VALUE newop = func(data, op);
+        if (newop != op) {
+            code[page_offset + offset] = newop;
+            if (data) {
+                VALUE *original_iseq = (VALUE *)data;
+                original_iseq[page_offset + offset] = newop;
             }
-            break;
-          case TS_IVC:
-          case TS_ICVARC:
-            {
-                IVC ivc = (IVC)code[pos + op_no + 1];
-                if (ivc->entry) {
-                    if (RB_TYPE_P(ivc->entry->class_value, T_NONE)) {
-                        rb_bug("!! %u", ivc->entry->index);
-                    }
-                    VALUE nv = func(data, ivc->entry->class_value);
-                    if (ivc->entry->class_value != nv) {
-                        ivc->entry->class_value = nv;
-                    }
-                }
-            }
-            break;
-          case TS_ISE:
-            {
-              union iseq_inline_storage_entry *const is = (union iseq_inline_storage_entry *)code[pos + op_no + 1];
-              if (is->once.value) {
-                  VALUE nv = func(data, is->once.value);
-                  if (is->once.value != nv) {
-                      is->once.value = nv;
-                  }
-              }
-            }
-            break;
-          default:
-            break;
-	}
+        }
+        bits &= bits - 1; // Reset Lowest Set Bit (BLSR)
     }
-
-    return len;
 }
 
 static void
@@ -315,52 +237,66 @@ rb_iseq_each_value(const rb_iseq_t *iseq, iseq_value_itr_t * func, void *data)
 {
     unsigned int size;
     VALUE *code;
-    size_t n;
-    rb_vm_insns_translator_t *const translator =
-#if OPT_DIRECT_THREADED_CODE || OPT_CALL_THREADED_CODE
-        (FL_TEST((VALUE)iseq, ISEQ_TRANSLATED)) ? rb_vm_insn_addr2insn2 :
-#endif
-        rb_vm_insn_null_translator;
     const struct rb_iseq_constant_body *const body = ISEQ_BODY(iseq);
 
     size = body->iseq_size;
     code = body->iseq_encoded;
 
-    for (n = 0; n < size;) {
-	n += iseq_extract_values(code, n, func, data, translator);
-    }
-}
+    union iseq_inline_storage_entry *is_entries = body->is_entries;
 
-// Similar to rb_iseq_each_value, except that this walks through each
-// instruction instead of the associated VALUEs. The provided iterator should
-// return a boolean that indicates whether or not to continue iterating.
-void
-rb_iseq_each(const rb_iseq_t *iseq, size_t start_index, rb_iseq_each_i iterator, void *data)
-{
-    unsigned int size;
-    VALUE *code;
-    size_t index;
-
-    rb_vm_insns_translator_t *const translator =
-#if OPT_DIRECT_THREADED_CODE || OPT_CALL_THREADED_CODE
-        (FL_TEST((VALUE)iseq, ISEQ_TRANSLATED)) ? rb_vm_insn_addr2insn2 :
-#endif
-        rb_vm_insn_normalizing_translator; // Always pass non-trace opcodes.
+    if (body->is_entries) {
+        // Skip iterating over ivc caches
+        is_entries += body->ivc_size;
 
-    const struct rb_iseq_constant_body *const body = ISEQ_BODY(iseq);
+        // ICVARC entries
+        for (unsigned int i = 0; i < body->icvarc_size; i++, is_entries++) {
+            ICVARC icvarc = (ICVARC)is_entries;
+            if (icvarc->entry) {
+                RUBY_ASSERT(!RB_TYPE_P(icvarc->entry->class_value, T_NONE));
 
-    size = body->iseq_size;
-    code = body->iseq_encoded;
+                VALUE nv = func(data, icvarc->entry->class_value);
+                if (icvarc->entry->class_value != nv) {
+                    icvarc->entry->class_value = nv;
+                }
+            }
+        }
 
-    for (index = start_index; index < size;) {
-        void *addr = (void *) code[index];
-        VALUE insn = translator(addr);
+        // ISE entries
+        for (unsigned int i = 0; i < body->ise_size; i++, is_entries++) {
+            union iseq_inline_storage_entry *const is = (union iseq_inline_storage_entry *)is_entries;
+            if (is->once.value) {
+                VALUE nv = func(data, is->once.value);
+                if (is->once.value != nv) {
+                    is->once.value = nv;
+                }
+            }
+        }
 
-        if (!iterator(code, insn, index, data)) {
-            break;
+        // IC Entries
+        for (unsigned int i = 0; i < body->ic_size; i++, is_entries++) {
+            IC ic = (IC)is_entries;
+            if (ic->entry) {
+                VALUE nv = func(data, (VALUE)ic->entry);
+                if ((VALUE)ic->entry != nv) {
+                    ic->entry = (void *)nv;
+                }
+            }
         }
+    }
 
-        index += insn_len(insn);
+    // Embedded VALUEs
+    if (body->mark_bits.list) {
+        if (ISEQ_MBITS_BUFLEN(size) == 1) {
+            iseq_scan_bits(0, body->mark_bits.single, code, func, data);
+        }
+        else {
+            if (body->mark_bits.list) {
+                for (unsigned int i = 0; i < ISEQ_MBITS_BUFLEN(size); i++) {
+                    iseq_bits_t bits = body->mark_bits.list[i];
+                    iseq_scan_bits(i, bits, code, func, data);
+                }
+            }
+        }
     }
 }
 
@@ -400,17 +336,8 @@ rb_iseq_update_references(rb_iseq_t *iseq)
                 cds[i].cc = (struct rb_callcache *)rb_gc_location((VALUE)cds[i].cc);
             }
         }
-        if (FL_TEST((VALUE)iseq, ISEQ_MARKABLE_ISEQ)) {
-            rb_iseq_each_value(iseq, update_each_insn_value, NULL);
-            VALUE *original_iseq = ISEQ_ORIGINAL_ISEQ(iseq);
-            if (original_iseq) {
-                size_t n = 0;
-                const unsigned int size = body->iseq_size;
-                while (n < size) {
-                    n += iseq_extract_values(original_iseq, n, update_each_insn_value, NULL, rb_vm_insn_null_translator);
-                }
-            }
-        }
+        VALUE *original_iseq = ISEQ_ORIGINAL_ISEQ(iseq);
+        rb_iseq_each_value(iseq, update_each_insn_value, (void *)original_iseq);
 
         if (body->param.flags.has_kw && ISEQ_COMPILE_DATA(iseq) == NULL) {
             int i, j;
@@ -419,7 +346,7 @@ rb_iseq_update_references(rb_iseq_t *iseq)
 
             for (j = 0; i < body->param.keyword->num; i++, j++) {
                 VALUE obj = body->param.keyword->default_values[j];
-                if (obj != Qundef) {
+                if (!UNDEF_P(obj)) {
                     body->param.keyword->default_values[j] = rb_gc_location(obj);
                 }
             }
@@ -439,7 +366,9 @@ rb_iseq_update_references(rb_iseq_t *iseq)
 #if USE_MJIT
         mjit_update_references(iseq);
 #endif
-        rb_yjit_iseq_update_references(body);
+#if USE_YJIT
+        rb_yjit_iseq_update_references(body->yjit_payload);
+#endif
     }
 }
 
@@ -460,9 +389,7 @@ rb_iseq_mark(const rb_iseq_t *iseq)
     if (ISEQ_BODY(iseq)) {
         const struct rb_iseq_constant_body *const body = ISEQ_BODY(iseq);
 
-        if (FL_TEST((VALUE)iseq, ISEQ_MARKABLE_ISEQ)) {
-	    rb_iseq_each_value(iseq, each_insn_value, NULL);
-	}
+        rb_iseq_each_value(iseq, each_insn_value, NULL);
 
         rb_gc_mark_movable(body->variable.coverage);
         rb_gc_mark_movable(body->variable.pc2branchindex);
@@ -498,43 +425,45 @@ rb_iseq_mark(const rb_iseq_t *iseq)
             }
         }
 
-	if (body->param.flags.has_kw && ISEQ_COMPILE_DATA(iseq) == NULL) {
-	    const struct rb_iseq_param_keyword *const keyword = body->param.keyword;
-	    int i, j;
+        if (body->param.flags.has_kw && ISEQ_COMPILE_DATA(iseq) == NULL) {
+            const struct rb_iseq_param_keyword *const keyword = body->param.keyword;
+            int i, j;
 
-	    i = keyword->required_num;
+            i = keyword->required_num;
 
-	    for (j = 0; i < keyword->num; i++, j++) {
-		VALUE obj = keyword->default_values[j];
-		if (!SPECIAL_CONST_P(obj)) {
+            for (j = 0; i < keyword->num; i++, j++) {
+                VALUE obj = keyword->default_values[j];
+                if (!SPECIAL_CONST_P(obj)) {
                     rb_gc_mark_movable(obj);
-		}
-	    }
-	}
-
-	if (body->catch_table) {
-	    const struct iseq_catch_table *table = body->catch_table;
-	    unsigned int i;
-	    for (i = 0; i < table->size; i++) {
-		const struct iseq_catch_table_entry *entry;
-		entry = UNALIGNED_MEMBER_PTR(table, entries[i]);
-		if (entry->iseq) {
+                }
+            }
+        }
+
+        if (body->catch_table) {
+            const struct iseq_catch_table *table = body->catch_table;
+            unsigned int i;
+            for (i = 0; i < table->size; i++) {
+                const struct iseq_catch_table_entry *entry;
+                entry = UNALIGNED_MEMBER_PTR(table, entries[i]);
+                if (entry->iseq) {
                     rb_gc_mark_movable((VALUE)entry->iseq);
-		}
-	    }
-	}
+                }
+            }
+        }
 
 #if USE_MJIT
         mjit_mark_cc_entries(body);
 #endif
-        rb_yjit_iseq_mark(body);
+#if USE_YJIT
+        rb_yjit_iseq_mark(body->yjit_payload);
+#endif
     }
 
     if (FL_TEST_RAW((VALUE)iseq, ISEQ_NOT_LOADED_YET)) {
-	rb_gc_mark(iseq->aux.loader.obj);
+        rb_gc_mark(iseq->aux.loader.obj);
     }
     else if (FL_TEST_RAW((VALUE)iseq, ISEQ_USE_COMPILE_DATA)) {
-	const struct iseq_compile_data *const compile_data = ISEQ_COMPILE_DATA(iseq);
+        const struct iseq_compile_data *const compile_data = ISEQ_COMPILE_DATA(iseq);
 
         rb_iseq_mark_insn_storage(compile_data->insn.storage_head);
 
@@ -582,6 +511,7 @@ rb_iseq_memsize(const rb_iseq_t *iseq)
         size += body->iseq_size * sizeof(VALUE);
         size += body->insns_info.size * (sizeof(struct iseq_insn_info_entry) + sizeof(unsigned int));
         size += body->local_table_size * sizeof(ID);
+        size += ISEQ_MBITS_BUFLEN(body->iseq_size) * ISEQ_MBITS_SIZE;
         if (body->catch_table) {
             size += iseq_catch_table_bytes(body->catch_table->size);
         }
@@ -589,7 +519,20 @@ rb_iseq_memsize(const rb_iseq_t *iseq)
         size += param_keyword_size(body->param.keyword);
 
         /* body->is_entries */
-        size += body->is_size * sizeof(union iseq_inline_storage_entry);
+        size += ISEQ_IS_SIZE(body) * sizeof(union iseq_inline_storage_entry);
+
+        if (ISEQ_BODY(iseq)->is_entries) {
+            /* IC entries constant segments */
+            for (unsigned int ic_idx = 0; ic_idx < body->ic_size; ic_idx++) {
+                IC ic = &ISEQ_IS_IC_ENTRY(body, ic_idx);
+                const ID *ids = ic->segments;
+                if (!ids) continue;
+                while (*ids++) {
+                    size += sizeof(ID);
+                }
+                size += sizeof(ID); // null terminator
+            }
+        }
 
         /* body->call_data */
         size += body->ci_size * sizeof(struct rb_call_data);
@@ -598,15 +541,15 @@ rb_iseq_memsize(const rb_iseq_t *iseq)
 
     compile_data = ISEQ_COMPILE_DATA(iseq);
     if (compile_data) {
-	struct iseq_compile_data_storage *cur;
+        struct iseq_compile_data_storage *cur;
 
-	size += sizeof(struct iseq_compile_data);
+        size += sizeof(struct iseq_compile_data);
 
-	cur = compile_data->node.storage_head;
-	while (cur) {
-	    size += cur->size + offsetof(struct iseq_compile_data_storage, buff);
-	    cur = cur->next;
-	}
+        cur = compile_data->node.storage_head;
+        while (cur) {
+            size += cur->size + offsetof(struct iseq_compile_data_storage, buff);
+            cur = cur->next;
+        }
     }
 
     return size;
@@ -636,13 +579,13 @@ rb_iseq_pathobj_new(VALUE path, VALUE realpath)
     VM_ASSERT(NIL_P(realpath) || RB_TYPE_P(realpath, T_STRING));
 
     if (path == realpath ||
-	(!NIL_P(realpath) && rb_str_cmp(path, realpath) == 0)) {
-	pathobj = rb_fstring(path);
+        (!NIL_P(realpath) && rb_str_cmp(path, realpath) == 0)) {
+        pathobj = rb_fstring(path);
     }
     else {
-	if (!NIL_P(realpath)) realpath = rb_fstring(realpath);
-	pathobj = rb_ary_new_from_args(2, rb_fstring(path), realpath);
-	rb_obj_freeze(pathobj);
+        if (!NIL_P(realpath)) realpath = rb_fstring(realpath);
+        pathobj = rb_ary_new_from_args(2, rb_fstring(path), realpath);
+        rb_obj_freeze(pathobj);
     }
     return pathobj;
 }
@@ -651,11 +594,24 @@ void
 rb_iseq_pathobj_set(const rb_iseq_t *iseq, VALUE path, VALUE realpath)
 {
     RB_OBJ_WRITE(iseq, &ISEQ_BODY(iseq)->location.pathobj,
-		 rb_iseq_pathobj_new(path, realpath));
+                 rb_iseq_pathobj_new(path, realpath));
+}
+
+// Make a dummy iseq for a dummy frame that exposes a path for profilers to inspect
+rb_iseq_t *
+rb_iseq_alloc_with_dummy_path(VALUE fname)
+{
+    rb_iseq_t *dummy_iseq = iseq_alloc();
+
+    ISEQ_BODY(dummy_iseq)->type = ISEQ_TYPE_TOP;
+    RB_OBJ_WRITE(dummy_iseq, &ISEQ_BODY(dummy_iseq)->location.pathobj, fname);
+    RB_OBJ_WRITE(dummy_iseq, &ISEQ_BODY(dummy_iseq)->location.label, fname);
+
+    return dummy_iseq;
 }
 
 static rb_iseq_location_t *
-iseq_location_setup(rb_iseq_t *iseq, VALUE name, VALUE path, VALUE realpath, VALUE first_lineno, const rb_code_location_t *code_location, const int node_id)
+iseq_location_setup(rb_iseq_t *iseq, VALUE name, VALUE path, VALUE realpath, int first_lineno, const rb_code_location_t *code_location, const int node_id)
 {
     rb_iseq_location_t *loc = &ISEQ_BODY(iseq)->location;
 
@@ -665,13 +621,13 @@ iseq_location_setup(rb_iseq_t *iseq, VALUE name, VALUE path, VALUE realpath, VAL
     loc->first_lineno = first_lineno;
     if (code_location) {
         loc->node_id = node_id;
-	loc->code_location = *code_location;
+        loc->code_location = *code_location;
     }
     else {
-	loc->code_location.beg_pos.lineno = 0;
-	loc->code_location.beg_pos.column = 0;
-	loc->code_location.end_pos.lineno = -1;
-	loc->code_location.end_pos.column = -1;
+        loc->code_location.beg_pos.lineno = 0;
+        loc->code_location.beg_pos.column = 0;
+        loc->code_location.end_pos.lineno = -1;
+        loc->code_location.end_pos.column = -1;
     }
 
     return loc;
@@ -685,21 +641,21 @@ set_relation(rb_iseq_t *iseq, const rb_iseq_t *piseq)
 
     /* set class nest stack */
     if (type == ISEQ_TYPE_TOP) {
-	body->local_iseq = iseq;
+        body->local_iseq = iseq;
     }
     else if (type == ISEQ_TYPE_METHOD || type == ISEQ_TYPE_CLASS) {
-	body->local_iseq = iseq;
+        body->local_iseq = iseq;
     }
     else if (piseq) {
         body->local_iseq = ISEQ_BODY(piseq)->local_iseq;
     }
 
     if (piseq) {
-	body->parent_iseq = piseq;
+        body->parent_iseq = piseq;
     }
 
     if (type == ISEQ_TYPE_MAIN) {
-	body->local_iseq = iseq;
+        body->local_iseq = iseq;
     }
 }
 
@@ -720,8 +676,8 @@ new_arena(void)
 
 static VALUE
 prepare_iseq_build(rb_iseq_t *iseq,
-                   VALUE name, VALUE path, VALUE realpath, VALUE first_lineno, const rb_code_location_t *code_location, const int node_id,
-		   const rb_iseq_t *parent, int isolated_depth, enum iseq_type type,
+                   VALUE name, VALUE path, VALUE realpath, int first_lineno, const rb_code_location_t *code_location, const int node_id,
+                   const rb_iseq_t *parent, int isolated_depth, enum rb_iseq_type type,
                    VALUE script_lines, const rb_compile_option_t *option)
 {
     VALUE coverage = Qfalse;
@@ -729,7 +685,7 @@ prepare_iseq_build(rb_iseq_t *iseq,
     struct rb_iseq_constant_body *const body = ISEQ_BODY(iseq);
 
     if (parent && (type == ISEQ_TYPE_MAIN || type == ISEQ_TYPE_TOP))
-	err_info = Qfalse;
+        err_info = Qfalse;
 
     body->type = type;
     set_relation(iseq, parent);
@@ -761,17 +717,16 @@ prepare_iseq_build(rb_iseq_t *iseq,
     ISEQ_COMPILE_DATA(iseq)->ivar_cache_table = NULL;
     ISEQ_COMPILE_DATA(iseq)->builtin_function_table = GET_VM()->builtin_function_table;
 
-
     if (option->coverage_enabled) {
-	VALUE coverages = rb_get_coverages();
-	if (RTEST(coverages)) {
-	    coverage = rb_hash_lookup(coverages, rb_iseq_path(iseq));
-	    if (NIL_P(coverage)) coverage = Qfalse;
-	}
+        VALUE coverages = rb_get_coverages();
+        if (RTEST(coverages)) {
+            coverage = rb_hash_lookup(coverages, rb_iseq_path(iseq));
+            if (NIL_P(coverage)) coverage = Qfalse;
+        }
     }
     ISEQ_COVERAGE_SET(iseq, coverage);
     if (coverage && ISEQ_BRANCH_COVERAGE(iseq))
-        ISEQ_PC2BRANCHINDEX_SET(iseq, rb_ary_tmp_new(0));
+        ISEQ_PC2BRANCHINDEX_SET(iseq, rb_ary_hidden_new(0));
 
     return Qtrue;
 }
@@ -832,10 +787,10 @@ finish_iseq_build(rb_iseq_t *iseq)
 #endif
 
     if (RTEST(err)) {
-	VALUE path = pathobj_path(body->location.pathobj);
-	if (err == Qtrue) err = rb_exc_new_cstr(rb_eSyntaxError, "compile error");
-	rb_funcallv(err, rb_intern("set_backtrace"), 1, &path);
-	rb_exc_raise(err);
+        VALUE path = pathobj_path(body->location.pathobj);
+        if (err == Qtrue) err = rb_exc_new_cstr(rb_eSyntaxError, "compile error");
+        rb_funcallv(err, rb_intern("set_backtrace"), 1, &path);
+        rb_exc_raise(err);
     }
 
     RB_DEBUG_COUNTER_INC(iseq_num);
@@ -898,22 +853,22 @@ static void
 make_compile_option(rb_compile_option_t *option, VALUE opt)
 {
     if (NIL_P(opt)) {
-	*option = COMPILE_OPTION_DEFAULT;
+        *option = COMPILE_OPTION_DEFAULT;
     }
     else if (opt == Qfalse) {
-	*option = COMPILE_OPTION_FALSE;
+        *option = COMPILE_OPTION_FALSE;
     }
     else if (opt == Qtrue) {
-	int i;
-	for (i = 0; i < (int)(sizeof(rb_compile_option_t) / sizeof(int)); ++i)
-	    ((int *)option)[i] = 1;
+        int i;
+        for (i = 0; i < (int)(sizeof(rb_compile_option_t) / sizeof(int)); ++i)
+            ((int *)option)[i] = 1;
     }
     else if (RB_TYPE_P(opt, T_HASH)) {
-	*option = COMPILE_OPTION_DEFAULT;
-	set_compile_option_from_hash(option, opt);
+        *option = COMPILE_OPTION_DEFAULT;
+        set_compile_option_from_hash(option, opt);
     }
     else {
-	rb_raise(rb_eTypeError, "Compile option must be Hash/true/false/nil");
+        rb_raise(rb_eTypeError, "Compile option must be Hash/true/false/nil");
     }
 }
 
@@ -926,17 +881,17 @@ make_compile_option_value(rb_compile_option_t *option)
 #define SET_COMPILE_OPTION_NUM(o, h, mem) \
   rb_hash_aset((h), ID2SYM(rb_intern(#mem)), INT2NUM((o)->mem))
     {
-	SET_COMPILE_OPTION(option, opt, inline_const_cache);
-	SET_COMPILE_OPTION(option, opt, peephole_optimization);
-	SET_COMPILE_OPTION(option, opt, tailcall_optimization);
-	SET_COMPILE_OPTION(option, opt, specialized_instruction);
-	SET_COMPILE_OPTION(option, opt, operands_unification);
-	SET_COMPILE_OPTION(option, opt, instructions_unification);
-	SET_COMPILE_OPTION(option, opt, stack_caching);
-	SET_COMPILE_OPTION(option, opt, frozen_string_literal);
-	SET_COMPILE_OPTION(option, opt, debug_frozen_string_literal);
-	SET_COMPILE_OPTION(option, opt, coverage_enabled);
-	SET_COMPILE_OPTION_NUM(option, opt, debug_level);
+        SET_COMPILE_OPTION(option, opt, inline_const_cache);
+        SET_COMPILE_OPTION(option, opt, peephole_optimization);
+        SET_COMPILE_OPTION(option, opt, tailcall_optimization);
+        SET_COMPILE_OPTION(option, opt, specialized_instruction);
+        SET_COMPILE_OPTION(option, opt, operands_unification);
+        SET_COMPILE_OPTION(option, opt, instructions_unification);
+        SET_COMPILE_OPTION(option, opt, stack_caching);
+        SET_COMPILE_OPTION(option, opt, frozen_string_literal);
+        SET_COMPILE_OPTION(option, opt, debug_frozen_string_literal);
+        SET_COMPILE_OPTION(option, opt, coverage_enabled);
+        SET_COMPILE_OPTION_NUM(option, opt, debug_level);
     }
 #undef SET_COMPILE_OPTION
 #undef SET_COMPILE_OPTION_NUM
@@ -945,9 +900,9 @@ make_compile_option_value(rb_compile_option_t *option)
 
 rb_iseq_t *
 rb_iseq_new(const rb_ast_body_t *ast, VALUE name, VALUE path, VALUE realpath,
-	    const rb_iseq_t *parent, enum iseq_type type)
+            const rb_iseq_t *parent, enum rb_iseq_type type)
 {
-    return rb_iseq_new_with_opt(ast, name, path, realpath, INT2FIX(0), parent,
+    return rb_iseq_new_with_opt(ast, name, path, realpath, 0, parent,
                                 0, type, &COMPILE_OPTION_DEFAULT);
 }
 
@@ -964,34 +919,62 @@ ast_line_count(const rb_ast_body_t *ast)
     return FIX2INT(ast->script_lines);
 }
 
-rb_iseq_t *
-rb_iseq_new_top(const rb_ast_body_t *ast, VALUE name, VALUE path, VALUE realpath, const rb_iseq_t *parent)
+static VALUE
+iseq_setup_coverage(VALUE coverages, VALUE path, const rb_ast_body_t *ast, int line_offset)
+{
+    int line_count = line_offset + ast_line_count(ast);
+
+    if (line_count >= 0) {
+        int len = (rb_get_coverage_mode() & COVERAGE_TARGET_ONESHOT_LINES) ? 0 : line_count;
+
+        VALUE coverage = rb_default_coverage(len);
+        rb_hash_aset(coverages, path, coverage);
+
+        return coverage;
+    }
+
+    return Qnil;
+}
+
+static inline void
+iseq_new_setup_coverage(VALUE path, const rb_ast_body_t *ast, int line_offset)
 {
     VALUE coverages = rb_get_coverages();
+
     if (RTEST(coverages)) {
-        int line_count = ast_line_count(ast);
-        if (line_count >= 0) {
-            int len = (rb_get_coverage_mode() & COVERAGE_TARGET_ONESHOT_LINES) ? 0 : line_count;
-            VALUE coverage = rb_default_coverage(len);
-            rb_hash_aset(coverages, path, coverage);
-        }
+        iseq_setup_coverage(coverages, path, ast, 0);
     }
+}
+
+rb_iseq_t *
+rb_iseq_new_top(const rb_ast_body_t *ast, VALUE name, VALUE path, VALUE realpath, const rb_iseq_t *parent)
+{
+    iseq_new_setup_coverage(path, ast, 0);
 
-    return rb_iseq_new_with_opt(ast, name, path, realpath, INT2FIX(0), parent, 0,
+    return rb_iseq_new_with_opt(ast, name, path, realpath, 0, parent, 0,
                                 ISEQ_TYPE_TOP, &COMPILE_OPTION_DEFAULT);
 }
 
 rb_iseq_t *
 rb_iseq_new_main(const rb_ast_body_t *ast, VALUE path, VALUE realpath, const rb_iseq_t *parent, int opt)
 {
+    iseq_new_setup_coverage(path, ast, 0);
+
     return rb_iseq_new_with_opt(ast, rb_fstring_lit("<main>"),
-				path, realpath, INT2FIX(0),
-				parent, 0, ISEQ_TYPE_MAIN, opt ? &COMPILE_OPTION_DEFAULT : &COMPILE_OPTION_FALSE);
+                                path, realpath, 0,
+                                parent, 0, ISEQ_TYPE_MAIN, opt ? &COMPILE_OPTION_DEFAULT : &COMPILE_OPTION_FALSE);
 }
 
 rb_iseq_t *
-rb_iseq_new_eval(const rb_ast_body_t *ast, VALUE name, VALUE path, VALUE realpath, VALUE first_lineno, const rb_iseq_t *parent, int isolated_depth)
+rb_iseq_new_eval(const rb_ast_body_t *ast, VALUE name, VALUE path, VALUE realpath, int first_lineno, const rb_iseq_t *parent, int isolated_depth)
 {
+    if (rb_get_coverage_mode() & COVERAGE_TARGET_EVAL) {
+        VALUE coverages = rb_get_coverages();
+        if (RTEST(coverages) && RTEST(path) && !RTEST(rb_hash_has_key(coverages, path))) {
+            iseq_setup_coverage(coverages, path, ast, first_lineno - 1);
+        }
+    }
+
     return rb_iseq_new_with_opt(ast, name, path, realpath, first_lineno,
                                 parent, isolated_depth, ISEQ_TYPE_EVAL, &COMPILE_OPTION_DEFAULT);
 }
@@ -1000,11 +983,11 @@ static inline rb_iseq_t *
 iseq_translate(rb_iseq_t *iseq)
 {
     if (rb_respond_to(rb_cISeq, rb_intern("translate"))) {
-	VALUE v1 = iseqw_new(iseq);
-	VALUE v2 = rb_funcall(rb_cISeq, rb_intern("translate"), 1, v1);
-	if (v1 != v2 && CLASS_OF(v2) == rb_cISeq) {
-	    iseq = (rb_iseq_t *)iseqw_check(v2);
-	}
+        VALUE v1 = iseqw_new(iseq);
+        VALUE v2 = rb_funcall(rb_cISeq, rb_intern("translate"), 1, v1);
+        if (v1 != v2 && CLASS_OF(v2) == rb_cISeq) {
+            iseq = (rb_iseq_t *)iseqw_check(v2);
+        }
     }
 
     return iseq;
@@ -1012,8 +995,8 @@ iseq_translate(rb_iseq_t *iseq)
 
 rb_iseq_t *
 rb_iseq_new_with_opt(const rb_ast_body_t *ast, VALUE name, VALUE path, VALUE realpath,
-		     VALUE first_lineno, const rb_iseq_t *parent, int isolated_depth,
-                     enum iseq_type type, const rb_compile_option_t *option)
+                     int first_lineno, const rb_iseq_t *parent, int isolated_depth,
+                     enum rb_iseq_type type, const rb_compile_option_t *option)
 {
     const NODE *node = ast ? ast->root : 0;
     /* TODO: argument check */
@@ -1050,8 +1033,8 @@ rb_iseq_t *
 rb_iseq_new_with_callback(
     const struct rb_iseq_new_with_callback_callback_func * ifunc,
     VALUE name, VALUE path, VALUE realpath,
-    VALUE first_lineno, const rb_iseq_t *parent,
-    enum iseq_type type, const rb_compile_option_t *option)
+    int first_lineno, const rb_iseq_t *parent,
+    enum rb_iseq_type type, const rb_compile_option_t *option)
 {
     /* TODO: argument check */
     rb_iseq_t *iseq = iseq_alloc();
@@ -1071,7 +1054,7 @@ rb_iseq_load_iseq(VALUE fname)
     VALUE iseqv = rb_check_funcall(rb_cISeq, rb_intern("load_iseq"), 1, &fname);
 
     if (!SPECIAL_CONST_P(iseqv) && RBASIC_CLASS(iseqv) == rb_cISeq) {
-	return  iseqw_check(iseqv);
+        return  iseqw_check(iseqv);
     }
 
     return NULL;
@@ -1083,7 +1066,7 @@ rb_iseq_load_iseq(VALUE fname)
 #define CHECK_SYMBOL(v)  rb_to_symbol_type(v)
 static inline VALUE CHECK_INTEGER(VALUE v) {(void)NUM2LONG(v); return v;}
 
-static enum iseq_type
+static enum rb_iseq_type
 iseq_type_from_sym(VALUE type)
 {
     const ID id_top = rb_intern("top");
@@ -1107,7 +1090,7 @@ iseq_type_from_sym(VALUE type)
     if (typeid == id_eval) return ISEQ_TYPE_EVAL;
     if (typeid == id_main) return ISEQ_TYPE_MAIN;
     if (typeid == id_plain) return ISEQ_TYPE_PLAIN;
-    return (enum iseq_type)-1;
+    return (enum rb_iseq_type)-1;
 }
 
 static VALUE
@@ -1116,7 +1099,7 @@ iseq_load(VALUE data, const rb_iseq_t *parent, VALUE opt)
     rb_iseq_t *iseq = iseq_alloc();
 
     VALUE magic, version1, version2, format_type, misc;
-    VALUE name, path, realpath, first_lineno, code_location, node_id;
+    VALUE name, path, realpath, code_location, node_id;
     VALUE type, body, locals, params, exception;
 
     st_data_t iseq_type;
@@ -1142,7 +1125,7 @@ iseq_load(VALUE data, const rb_iseq_t *parent, VALUE opt)
     path        = CHECK_STRING(rb_ary_entry(data, i++));
     realpath    = rb_ary_entry(data, i++);
     realpath    = NIL_P(realpath) ? Qnil : CHECK_STRING(realpath);
-    first_lineno = CHECK_INTEGER(rb_ary_entry(data, i++));
+    int first_lineno = RB_NUM2INT(rb_ary_entry(data, i++));
 
     type        = CHECK_SYMBOL(rb_ary_entry(data, i++));
     locals      = CHECK_ARRAY(rb_ary_entry(data, i++));
@@ -1153,24 +1136,24 @@ iseq_load(VALUE data, const rb_iseq_t *parent, VALUE opt)
     ISEQ_BODY(iseq)->local_iseq = iseq;
 
     iseq_type = iseq_type_from_sym(type);
-    if (iseq_type == (enum iseq_type)-1) {
-	rb_raise(rb_eTypeError, "unsupported type: :%"PRIsVALUE, rb_sym2str(type));
+    if (iseq_type == (enum rb_iseq_type)-1) {
+        rb_raise(rb_eTypeError, "unsupported type: :%"PRIsVALUE, rb_sym2str(type));
     }
 
     node_id = rb_hash_aref(misc, ID2SYM(rb_intern("node_id")));
 
     code_location = rb_hash_aref(misc, ID2SYM(rb_intern("code_location")));
     if (RB_TYPE_P(code_location, T_ARRAY) && RARRAY_LEN(code_location) == 4) {
-	tmp_loc.beg_pos.lineno = NUM2INT(rb_ary_entry(code_location, 0));
-	tmp_loc.beg_pos.column = NUM2INT(rb_ary_entry(code_location, 1));
-	tmp_loc.end_pos.lineno = NUM2INT(rb_ary_entry(code_location, 2));
-	tmp_loc.end_pos.column = NUM2INT(rb_ary_entry(code_location, 3));
+        tmp_loc.beg_pos.lineno = NUM2INT(rb_ary_entry(code_location, 0));
+        tmp_loc.beg_pos.column = NUM2INT(rb_ary_entry(code_location, 1));
+        tmp_loc.end_pos.lineno = NUM2INT(rb_ary_entry(code_location, 2));
+        tmp_loc.end_pos.column = NUM2INT(rb_ary_entry(code_location, 3));
     }
 
     make_compile_option(&option, opt);
     option.peephole_optimization = FALSE; /* because peephole optimization can modify original iseq */
     prepare_iseq_build(iseq, name, path, realpath, first_lineno, &tmp_loc, NUM2INT(node_id),
-                       parent, 0, (enum iseq_type)iseq_type, Qnil, &option);
+                       parent, 0, (enum rb_iseq_type)iseq_type, Qnil, &option);
 
     rb_iseq_build_from_ary(iseq, misc, locals, params, exception, body);
 
@@ -1209,37 +1192,36 @@ rb_iseq_compile_with_option(VALUE src, VALUE file, VALUE realpath, VALUE line, V
     rb_ast_t *(*parse)(VALUE vparser, VALUE fname, VALUE file, int start);
     int ln;
     rb_ast_t *INITIALIZED ast;
+    VALUE name = rb_fstring_lit("<compiled>");
 
     /* safe results first */
     make_compile_option(&option, opt);
     ln = NUM2INT(line);
     StringValueCStr(file);
     if (RB_TYPE_P(src, T_FILE)) {
-	parse = rb_parser_compile_file_path;
+        parse = rb_parser_compile_file_path;
     }
     else {
-	parse = rb_parser_compile_string_path;
-	StringValue(src);
+        parse = rb_parser_compile_string_path;
+        StringValue(src);
     }
     {
-	const VALUE parser = rb_parser_new();
-        VALUE name = rb_fstring_lit("<compiled>");
+        const VALUE parser = rb_parser_new();
         const rb_iseq_t *outer_scope = rb_iseq_new(NULL, name, name, Qnil, 0, ISEQ_TYPE_TOP);
         VALUE outer_scope_v = (VALUE)outer_scope;
         rb_parser_set_context(parser, outer_scope, FALSE);
         RB_GC_GUARD(outer_scope_v);
-	ast = (*parse)(parser, file, src, ln);
+        ast = (*parse)(parser, file, src, ln);
     }
 
     if (!ast->body.root) {
-	rb_ast_dispose(ast);
-	rb_exc_raise(GET_EC()->errinfo);
+        rb_ast_dispose(ast);
+        rb_exc_raise(GET_EC()->errinfo);
     }
     else {
-	INITIALIZED VALUE label = rb_fstring_lit("<compiled>");
-	iseq = rb_iseq_new_with_opt(&ast->body, label, file, realpath, line,
-				    NULL, 0, ISEQ_TYPE_TOP, &option);
-	rb_ast_dispose(ast);
+        iseq = rb_iseq_new_with_opt(&ast->body, name, file, realpath, ln,
+                                    NULL, 0, ISEQ_TYPE_TOP, &option);
+        rb_ast_dispose(ast);
     }
 
     return iseq;
@@ -1284,7 +1266,7 @@ rb_iseq_base_label(const rb_iseq_t *iseq)
 VALUE
 rb_iseq_first_lineno(const rb_iseq_t *iseq)
 {
-    return ISEQ_BODY(iseq)->location.first_lineno;
+    return RB_INT2NUM(ISEQ_BODY(iseq)->location.first_lineno);
 }
 
 VALUE
@@ -1293,10 +1275,10 @@ rb_iseq_method_name(const rb_iseq_t *iseq)
     struct rb_iseq_constant_body *const body = ISEQ_BODY(ISEQ_BODY(iseq)->local_iseq);
 
     if (body->type == ISEQ_TYPE_METHOD) {
-	return body->location.base_label;
+        return body->location.base_label;
     }
     else {
-	return Qnil;
+        return Qnil;
     }
 }
 
@@ -1310,7 +1292,7 @@ rb_iseq_code_location(const rb_iseq_t *iseq, int *beg_pos_lineno, int *beg_pos_c
     if (end_pos_column) *end_pos_column = loc->end_pos.column;
 }
 
-static ID iseq_type_id(enum iseq_type type);
+static ID iseq_type_id(enum rb_iseq_type type);
 
 VALUE
 rb_iseq_type(const rb_iseq_t *iseq)
@@ -1332,10 +1314,10 @@ remove_coverage_i(void *vstart, void *vend, size_t stride, void *data)
         void *ptr = asan_poisoned_object_p(v);
         asan_unpoison_object(v, false);
 
-	if (rb_obj_is_iseq(v)) {
+        if (rb_obj_is_iseq(v)) {
             rb_iseq_t *iseq = (rb_iseq_t *)v;
             ISEQ_COVERAGE_SET(iseq, Qnil);
-	}
+        }
 
         asan_poison_object_if(ptr, v);
     }
@@ -1476,7 +1458,7 @@ iseqw_s_compile(int argc, VALUE *argv, VALUE self)
 static VALUE
 iseqw_s_compile_file(int argc, VALUE *argv, VALUE self)
 {
-    VALUE file, line = INT2FIX(1), opt = Qnil;
+    VALUE file, opt = Qnil;
     VALUE parser, f, exc = Qnil, ret;
     rb_ast_t *ast;
     rb_compile_option_t option;
@@ -1492,6 +1474,9 @@ iseqw_s_compile_file(int argc, VALUE *argv, VALUE self)
 
     f = rb_file_open_str(file, "r");
 
+    rb_execution_context_t *ec = GET_EC();
+    VALUE v = rb_vm_push_frame_fname(ec, file);
+
     parser = rb_parser_new();
     rb_parser_set_context(parser, NULL, FALSE);
     ast = (rb_ast_t *)rb_parser_load_file(parser, file);
@@ -1499,17 +1484,20 @@ iseqw_s_compile_file(int argc, VALUE *argv, VALUE self)
 
     rb_io_close(f);
     if (!ast->body.root) {
-	rb_ast_dispose(ast);
-	rb_exc_raise(exc);
+        rb_ast_dispose(ast);
+        rb_exc_raise(exc);
     }
 
     make_compile_option(&option, opt);
 
     ret = iseqw_new(rb_iseq_new_with_opt(&ast->body, rb_fstring_lit("<main>"),
-					 file,
-					 rb_realpath_internal(Qnil, file, 1),
-					 line, NULL, 0, ISEQ_TYPE_TOP, &option));
+                                         file,
+                                         rb_realpath_internal(Qnil, file, 1),
+                                         1, NULL, 0, ISEQ_TYPE_TOP, &option));
     rb_ast_dispose(ast);
+
+    rb_vm_pop_frame(ec);
+    RB_GC_GUARD(v);
     return ret;
 }
 
@@ -1573,11 +1561,11 @@ iseqw_check(VALUE iseqw)
     rb_iseq_t *iseq = DATA_PTR(iseqw);
 
     if (!ISEQ_BODY(iseq)) {
-	rb_ibf_load_iseq_complete(iseq);
+        rb_ibf_load_iseq_complete(iseq);
     }
 
     if (!ISEQ_BODY(iseq)->location.label) {
-	rb_raise(rb_eTypeError, "uninitialized InstructionSequence");
+        rb_raise(rb_eTypeError, "uninitialized InstructionSequence");
     }
     return iseq;
 }
@@ -1599,7 +1587,11 @@ rb_iseqw_to_iseq(VALUE iseqw)
 static VALUE
 iseqw_eval(VALUE self)
 {
-    return rb_iseq_eval(iseqw_check(self));
+    const rb_iseq_t *iseq = iseqw_check(self);
+    if (0 == ISEQ_BODY(iseq)->iseq_size) {
+        rb_raise(rb_eTypeError, "attempt to evaluate dummy InstructionSequence");
+    }
+    return rb_iseq_eval(iseq);
 }
 
 /*
@@ -1614,13 +1606,13 @@ iseqw_inspect(VALUE self)
     VALUE klass = rb_class_name(rb_obj_class(self));
 
     if (!body->location.label) {
-	return rb_sprintf("#<%"PRIsVALUE": uninitialized>", klass);
+        return rb_sprintf("#<%"PRIsVALUE": uninitialized>", klass);
     }
     else {
-	return rb_sprintf("<%"PRIsVALUE":%"PRIsVALUE"@%"PRIsVALUE":%d>",
-			  klass,
-			  body->location.label, rb_iseq_path(iseq),
-			  FIX2INT(rb_iseq_first_lineno(iseq)));
+        return rb_sprintf("<%"PRIsVALUE":%"PRIsVALUE"@%"PRIsVALUE":%d>",
+                          klass,
+                          body->location.label, rb_iseq_path(iseq),
+                          FIX2INT(rb_iseq_first_lineno(iseq)));
     }
 }
 
@@ -1847,38 +1839,38 @@ get_insn_info_binary_search(const rb_iseq_t *iseq, size_t pos)
     const int debug = 0;
 
     if (debug) {
-	printf("size: %"PRIuSIZE"\n", size);
-	printf("insns_info[%"PRIuSIZE"]: position: %d, line: %d, pos: %"PRIuSIZE"\n",
-	       (size_t)0, positions[0], insns_info[0].line_no, pos);
+        printf("size: %"PRIuSIZE"\n", size);
+        printf("insns_info[%"PRIuSIZE"]: position: %d, line: %d, pos: %"PRIuSIZE"\n",
+               (size_t)0, positions[0], insns_info[0].line_no, pos);
     }
 
     if (size == 0) {
-	return NULL;
+        return NULL;
     }
     else if (size == 1) {
-	return &insns_info[0];
+        return &insns_info[0];
     }
     else {
-	size_t l = 1, r = size - 1;
-	while (l <= r) {
-	    size_t m = l + (r - l) / 2;
-	    if (positions[m] == pos) {
-		return &insns_info[m];
-	    }
-	    if (positions[m] < pos) {
-		l = m + 1;
-	    }
-	    else {
-		r = m - 1;
-	    }
-	}
-	if (l >= size) {
-	    return &insns_info[size-1];
-	}
-	if (positions[l] > pos) {
-	    return &insns_info[l-1];
-	}
-	return &insns_info[l];
+        size_t l = 1, r = size - 1;
+        while (l <= r) {
+            size_t m = l + (r - l) / 2;
+            if (positions[m] == pos) {
+                return &insns_info[m];
+            }
+            if (positions[m] < pos) {
+                l = m + 1;
+            }
+            else {
+                r = m - 1;
+            }
+        }
+        if (l >= size) {
+            return &insns_info[size-1];
+        }
+        if (positions[l] > pos) {
+            return &insns_info[l-1];
+        }
+        return &insns_info[l];
     }
 }
 
@@ -1912,16 +1904,16 @@ get_insn_info_succinct_bitvector(const rb_iseq_t *iseq, size_t pos)
     }
 
     if (size == 0) {
-	return NULL;
+        return NULL;
     }
     else if (size == 1) {
-	return &insns_info[0];
+        return &insns_info[0];
     }
     else {
-	int index;
-	VM_ASSERT(body->insns_info.succ_index_table != NULL);
-	index = succ_index_lookup(body->insns_info.succ_index_table, (int)pos);
-	return &insns_info[index-1];
+        int index;
+        VM_ASSERT(body->insns_info.succ_index_table != NULL);
+        index = succ_index_lookup(body->insns_info.succ_index_table, (int)pos);
+        return &insns_info[index-1];
     }
 }
 
@@ -1943,29 +1935,29 @@ get_insn_info_linear_search(const rb_iseq_t *iseq, size_t pos)
     const int debug = 0;
 
     if (debug) {
-	printf("size: %"PRIuSIZE"\n", size);
-	printf("insns_info[%"PRIuSIZE"]: position: %d, line: %d, pos: %"PRIuSIZE"\n",
-	       i, positions[i], insns_info[i].line_no, pos);
+        printf("size: %"PRIuSIZE"\n", size);
+        printf("insns_info[%"PRIuSIZE"]: position: %d, line: %d, pos: %"PRIuSIZE"\n",
+               i, positions[i], insns_info[i].line_no, pos);
     }
 
     if (size == 0) {
-	return NULL;
+        return NULL;
     }
     else if (size == 1) {
-	return &insns_info[0];
+        return &insns_info[0];
     }
     else {
-	for (i=1; i<size; i++) {
-	    if (debug) printf("insns_info[%"PRIuSIZE"]: position: %d, line: %d, pos: %"PRIuSIZE"\n",
-			      i, positions[i], insns_info[i].line_no, pos);
-
-	    if (positions[i] == pos) {
-		return &insns_info[i];
-	    }
-	    if (positions[i] > pos) {
-		return &insns_info[i-1];
-	    }
-	}
+        for (i=1; i<size; i++) {
+            if (debug) printf("insns_info[%"PRIuSIZE"]: position: %d, line: %d, pos: %"PRIuSIZE"\n",
+                              i, positions[i], insns_info[i].line_no, pos);
+
+            if (positions[i] == pos) {
+                return &insns_info[i];
+            }
+            if (positions[i] > pos) {
+                return &insns_info[i-1];
+            }
+        }
     }
     return &insns_info[i-1];
 }
@@ -1986,9 +1978,9 @@ validate_get_insn_info(const rb_iseq_t *iseq)
     const struct rb_iseq_constant_body *const body = ISEQ_BODY(iseq);
     size_t i;
     for (i = 0; i < body->iseq_size; i++) {
-	if (get_insn_info_linear_search(iseq, i) != get_insn_info(iseq, i)) {
-	    rb_bug("validate_get_insn_info: get_insn_info_linear_search(iseq, %"PRIuSIZE") != get_insn_info(iseq, %"PRIuSIZE")", i, i);
-	}
+        if (get_insn_info_linear_search(iseq, i) != get_insn_info(iseq, i)) {
+            rb_bug("validate_get_insn_info: get_insn_info_linear_search(iseq, %"PRIuSIZE") != get_insn_info(iseq, %"PRIuSIZE")", i, i);
+        }
     }
 }
 #endif
@@ -1999,10 +1991,10 @@ rb_iseq_line_no(const rb_iseq_t *iseq, size_t pos)
     const struct iseq_insn_info_entry *entry = get_insn_info(iseq, pos);
 
     if (entry) {
-	return entry->line_no;
+        return entry->line_no;
     }
     else {
-	return 0;
+        return 0;
     }
 }
 
@@ -2013,10 +2005,10 @@ rb_iseq_node_id(const rb_iseq_t *iseq, size_t pos)
     const struct iseq_insn_info_entry *entry = get_insn_info(iseq, pos);
 
     if (entry) {
-	return entry->node_id;
+        return entry->node_id;
     }
     else {
-	return 0;
+        return 0;
     }
 }
 #endif
@@ -2026,10 +2018,10 @@ rb_iseq_event_flags(const rb_iseq_t *iseq, size_t pos)
 {
     const struct iseq_insn_info_entry *entry = get_insn_info(iseq, pos);
     if (entry) {
-	return entry->events;
+        return entry->events;
     }
     else {
-	return 0;
+        return 0;
     }
 }
 
@@ -2061,13 +2053,13 @@ local_var_name(const rb_iseq_t *diseq, VALUE level, VALUE op)
     lid = ISEQ_BODY(diseq)->local_table[idx];
     name = rb_id2str(lid);
     if (!name) {
-	name = rb_str_new_cstr("?");
+        name = rb_str_new_cstr("?");
     }
     else if (!rb_str_symname_p(name)) {
-	name = rb_str_inspect(name);
+        name = rb_str_inspect(name);
     }
     else {
-	name = rb_str_dup(name);
+        name = rb_str_dup(name);
     }
     rb_str_catf(name, "@%d", idx);
     return name;
@@ -2078,8 +2070,8 @@ VALUE rb_dump_literal(VALUE lit);
 
 VALUE
 rb_insn_operand_intern(const rb_iseq_t *iseq,
-		       VALUE insn, int op_no, VALUE op,
-		       int len, size_t pos, const VALUE *pnop, VALUE child)
+                       VALUE insn, int op_no, VALUE op,
+                       int len, size_t pos, const VALUE *pnop, VALUE child)
 {
     const char *types = insn_op_types(insn);
     char type = types[op_no];
@@ -2087,157 +2079,167 @@ rb_insn_operand_intern(const rb_iseq_t *iseq,
 
     switch (type) {
       case TS_OFFSET:		/* LONG */
-	ret = rb_sprintf("%"PRIdVALUE, (VALUE)(pos + len + op));
-	break;
+        ret = rb_sprintf("%"PRIdVALUE, (VALUE)(pos + len + op));
+        break;
 
       case TS_NUM:		/* ULONG */
-	if (insn == BIN(defined) && op_no == 0) {
-	    enum defined_type deftype = (enum defined_type)op;
-	    switch (deftype) {
-	      case DEFINED_FUNC:
-		ret = rb_fstring_lit("func");
-		break;
-	      case DEFINED_REF:
-		ret = rb_fstring_lit("ref");
-		break;
-	      case DEFINED_CONST_FROM:
-		ret = rb_fstring_lit("constant-from");
-		break;
-	      default:
-		ret = rb_iseq_defined_string(deftype);
-		break;
-	    }
-	    if (ret) break;
-	}
-	else if (insn == BIN(checktype) && op_no == 0) {
-	    const char *type_str = rb_type_str((enum ruby_value_type)op);
-	    if (type_str) {
-		ret = rb_str_new_cstr(type_str); break;
-	    }
-	}
-	ret = rb_sprintf("%"PRIuVALUE, op);
-	break;
+        if (insn == BIN(defined) && op_no == 0) {
+            enum defined_type deftype = (enum defined_type)op;
+            switch (deftype) {
+              case DEFINED_FUNC:
+                ret = rb_fstring_lit("func");
+                break;
+              case DEFINED_REF:
+                ret = rb_fstring_lit("ref");
+                break;
+              case DEFINED_CONST_FROM:
+                ret = rb_fstring_lit("constant-from");
+                break;
+              default:
+                ret = rb_iseq_defined_string(deftype);
+                break;
+            }
+            if (ret) break;
+        }
+        else if (insn == BIN(checktype) && op_no == 0) {
+            const char *type_str = rb_type_str((enum ruby_value_type)op);
+            if (type_str) {
+                ret = rb_str_new_cstr(type_str); break;
+            }
+        }
+        ret = rb_sprintf("%"PRIuVALUE, op);
+        break;
 
       case TS_LINDEX:{
-	int level;
-	if (types[op_no+1] == TS_NUM && pnop) {
-	    ret = local_var_name(iseq, *pnop, op - VM_ENV_DATA_SIZE);
-	}
-	else if ((level = rb_insn_unified_local_var_level(insn)) >= 0) {
-	    ret = local_var_name(iseq, (VALUE)level, op - VM_ENV_DATA_SIZE);
-	}
-	else {
-	    ret = rb_inspect(INT2FIX(op));
-	}
-	break;
+        int level;
+        if (types[op_no+1] == TS_NUM && pnop) {
+            ret = local_var_name(iseq, *pnop, op - VM_ENV_DATA_SIZE);
+        }
+        else if ((level = rb_insn_unified_local_var_level(insn)) >= 0) {
+            ret = local_var_name(iseq, (VALUE)level, op - VM_ENV_DATA_SIZE);
+        }
+        else {
+            ret = rb_inspect(INT2FIX(op));
+        }
+        break;
       }
       case TS_ID:		/* ID (symbol) */
-	ret = rb_inspect(ID2SYM(op));
-	break;
+        ret = rb_inspect(ID2SYM(op));
+        break;
 
       case TS_VALUE:		/* VALUE */
-	op = obj_resurrect(op);
-	if (insn == BIN(defined) && op_no == 1 && FIXNUM_P(op)) {
-	    /* should be DEFINED_REF */
-	    int type = NUM2INT(op);
-	    if (type) {
-		if (type & 1) {
-		    ret = rb_sprintf(":$%c", (type >> 1));
-		}
-		else {
-		    ret = rb_sprintf(":$%d", (type >> 1));
-		}
-		break;
-	    }
-	}
-	ret = rb_dump_literal(op);
-	if (CLASS_OF(op) == rb_cISeq) {
-	    if (child) {
-		rb_ary_push(child, op);
-	    }
-	}
-	break;
+        op = obj_resurrect(op);
+        if (insn == BIN(defined) && op_no == 1 && FIXNUM_P(op)) {
+            /* should be DEFINED_REF */
+            int type = NUM2INT(op);
+            if (type) {
+                if (type & 1) {
+                    ret = rb_sprintf(":$%c", (type >> 1));
+                }
+                else {
+                    ret = rb_sprintf(":$%d", (type >> 1));
+                }
+                break;
+            }
+        }
+        ret = rb_dump_literal(op);
+        if (CLASS_OF(op) == rb_cISeq) {
+            if (child) {
+                rb_ary_push(child, op);
+            }
+        }
+        break;
 
       case TS_ISEQ:		/* iseq */
-	{
-	    if (op) {
-		const rb_iseq_t *iseq = rb_iseq_check((rb_iseq_t *)op);
+        {
+            if (op) {
+                const rb_iseq_t *iseq = rb_iseq_check((rb_iseq_t *)op);
                 ret = ISEQ_BODY(iseq)->location.label;
-		if (child) {
-		    rb_ary_push(child, (VALUE)iseq);
-		}
-	    }
-	    else {
-		ret = rb_str_new2("nil");
-	    }
-	    break;
-	}
+                if (child) {
+                    rb_ary_push(child, (VALUE)iseq);
+                }
+            }
+            else {
+                ret = rb_str_new2("nil");
+            }
+            break;
+        }
 
       case TS_IC:
+        {
+            ret = rb_sprintf("<ic:%"PRIdPTRDIFF" ", (union iseq_inline_storage_entry *)op - ISEQ_BODY(iseq)->is_entries);
+            const ID *segments = ((IC)op)->segments;
+            rb_str_cat2(ret, rb_id2name(*segments++));
+            while (*segments) {
+                rb_str_catf(ret, "::%s", rb_id2name(*segments++));
+            }
+            rb_str_cat2(ret, ">");
+        }
+        break;
       case TS_IVC:
       case TS_ICVARC:
       case TS_ISE:
         ret = rb_sprintf("<is:%"PRIdPTRDIFF">", (union iseq_inline_storage_entry *)op - ISEQ_BODY(iseq)->is_entries);
-	break;
+        break;
 
       case TS_CALLDATA:
-	{
+        {
             struct rb_call_data *cd = (struct rb_call_data *)op;
             const struct rb_callinfo *ci = cd->ci;
-	    VALUE ary = rb_ary_new();
+            VALUE ary = rb_ary_new();
             ID mid = vm_ci_mid(ci);
 
             if (mid) {
-		rb_ary_push(ary, rb_sprintf("mid:%"PRIsVALUE, rb_id2str(mid)));
-	    }
+                rb_ary_push(ary, rb_sprintf("mid:%"PRIsVALUE, rb_id2str(mid)));
+            }
 
-	    rb_ary_push(ary, rb_sprintf("argc:%d", vm_ci_argc(ci)));
+            rb_ary_push(ary, rb_sprintf("argc:%d", vm_ci_argc(ci)));
 
             if (vm_ci_flag(ci) & VM_CALL_KWARG) {
                 const struct rb_callinfo_kwarg *kw_args = vm_ci_kwarg(ci);
                 VALUE kw_ary = rb_ary_new_from_values(kw_args->keyword_len, kw_args->keywords);
                 rb_ary_push(ary, rb_sprintf("kw:[%"PRIsVALUE"]", rb_ary_join(kw_ary, rb_str_new2(","))));
-	    }
+            }
 
             if (vm_ci_flag(ci)) {
-		VALUE flags = rb_ary_new();
+                VALUE flags = rb_ary_new();
 # define CALL_FLAG(n) if (vm_ci_flag(ci) & VM_CALL_##n) rb_ary_push(flags, rb_str_new2(#n))
-		CALL_FLAG(ARGS_SPLAT);
-		CALL_FLAG(ARGS_BLOCKARG);
-		CALL_FLAG(FCALL);
-		CALL_FLAG(VCALL);
-		CALL_FLAG(ARGS_SIMPLE);
-		CALL_FLAG(BLOCKISEQ);
-		CALL_FLAG(TAILCALL);
-		CALL_FLAG(SUPER);
-		CALL_FLAG(ZSUPER);
-		CALL_FLAG(KWARG);
-		CALL_FLAG(KW_SPLAT);
+                CALL_FLAG(ARGS_SPLAT);
+                CALL_FLAG(ARGS_BLOCKARG);
+                CALL_FLAG(FCALL);
+                CALL_FLAG(VCALL);
+                CALL_FLAG(ARGS_SIMPLE);
+                CALL_FLAG(BLOCKISEQ);
+                CALL_FLAG(TAILCALL);
+                CALL_FLAG(SUPER);
+                CALL_FLAG(ZSUPER);
+                CALL_FLAG(KWARG);
+                CALL_FLAG(KW_SPLAT);
                 CALL_FLAG(KW_SPLAT_MUT);
-		CALL_FLAG(OPT_SEND); /* maybe not reachable */
-		rb_ary_push(ary, rb_ary_join(flags, rb_str_new2("|")));
-	    }
+                CALL_FLAG(OPT_SEND); /* maybe not reachable */
+                rb_ary_push(ary, rb_ary_join(flags, rb_str_new2("|")));
+            }
 
             ret = rb_sprintf("<calldata!%"PRIsVALUE">", rb_ary_join(ary, rb_str_new2(", ")));
         }
-	break;
+        break;
 
       case TS_CDHASH:
-	ret = rb_str_new2("<cdhash>");
-	break;
+        ret = rb_str_new2("<cdhash>");
+        break;
 
       case TS_FUNCPTR:
-	{
+        {
 #ifdef HAVE_DLADDR
-	    Dl_info info;
-	    if (dladdr((void *)op, &info) && info.dli_sname) {
-		ret = rb_str_new_cstr(info.dli_sname);
-		break;
-	    }
+            Dl_info info;
+            if (dladdr((void *)op, &info) && info.dli_sname) {
+                ret = rb_str_new_cstr(info.dli_sname);
+                break;
+            }
 #endif
-	    ret = rb_str_new2("<funcptr>");
-	}
-	break;
+            ret = rb_str_new2("<funcptr>");
+        }
+        break;
 
       case TS_BUILTIN:
         {
@@ -2248,7 +2250,7 @@ rb_insn_operand_intern(const rb_iseq_t *iseq,
         break;
 
       default:
-	rb_bug("unknown operand type: %c", type);
+        rb_bug("unknown operand type: %c", type);
     }
     return ret;
 }
@@ -2268,7 +2270,7 @@ right_strip(VALUE str)
  */
 int
 rb_iseq_disasm_insn(VALUE ret, const VALUE *code, size_t pos,
-		    const rb_iseq_t *iseq, VALUE child)
+                    const rb_iseq_t *iseq, VALUE child)
 {
     VALUE insn = code[pos];
     int len = insn_len(insn);
@@ -2279,60 +2281,60 @@ rb_iseq_disasm_insn(VALUE ret, const VALUE *code, size_t pos,
 
     insn_name_buff = insn_name(insn);
     if (1) {
-	extern const int rb_vm_max_insn_name_size;
-	rb_str_catf(str, "%04"PRIuSIZE" %-*s ", pos, rb_vm_max_insn_name_size, insn_name_buff);
+        extern const int rb_vm_max_insn_name_size;
+        rb_str_catf(str, "%04"PRIuSIZE" %-*s ", pos, rb_vm_max_insn_name_size, insn_name_buff);
     }
     else {
-	rb_str_catf(str, "%04"PRIuSIZE" %-28.*s ", pos,
-		    (int)strcspn(insn_name_buff, "_"), insn_name_buff);
+        rb_str_catf(str, "%04"PRIuSIZE" %-28.*s ", pos,
+                    (int)strcspn(insn_name_buff, "_"), insn_name_buff);
     }
 
     for (j = 0; types[j]; j++) {
-	VALUE opstr = rb_insn_operand_intern(iseq, insn, j, code[pos + j + 1],
-					     len, pos, &code[pos + j + 2],
-					     child);
-	rb_str_concat(str, opstr);
+        VALUE opstr = rb_insn_operand_intern(iseq, insn, j, code[pos + j + 1],
+                                             len, pos, &code[pos + j + 2],
+                                             child);
+        rb_str_concat(str, opstr);
 
-	if (types[j + 1]) {
-	    rb_str_cat2(str, ", ");
-	}
+        if (types[j + 1]) {
+            rb_str_cat2(str, ", ");
+        }
     }
 
     {
-	unsigned int line_no = rb_iseq_line_no(iseq, pos);
-	unsigned int prev = pos == 0 ? 0 : rb_iseq_line_no(iseq, pos - 1);
-	if (line_no && line_no != prev) {
-	    long slen = RSTRING_LEN(str);
-	    slen = (slen > 70) ? 0 : (70 - slen);
-	    str = rb_str_catf(str, "%*s(%4d)", (int)slen, "", line_no);
-	}
+        unsigned int line_no = rb_iseq_line_no(iseq, pos);
+        unsigned int prev = pos == 0 ? 0 : rb_iseq_line_no(iseq, pos - 1);
+        if (line_no && line_no != prev) {
+            long slen = RSTRING_LEN(str);
+            slen = (slen > 70) ? 0 : (70 - slen);
+            str = rb_str_catf(str, "%*s(%4d)", (int)slen, "", line_no);
+        }
     }
 
     {
-	rb_event_flag_t events = rb_iseq_event_flags(iseq, pos);
-	if (events) {
+        rb_event_flag_t events = rb_iseq_event_flags(iseq, pos);
+        if (events) {
             str = rb_str_catf(str, "[%s%s%s%s%s%s%s%s%s%s%s]",
-			      events & RUBY_EVENT_LINE     ? "Li" : "",
-			      events & RUBY_EVENT_CLASS    ? "Cl" : "",
-			      events & RUBY_EVENT_END      ? "En" : "",
-			      events & RUBY_EVENT_CALL     ? "Ca" : "",
-			      events & RUBY_EVENT_RETURN   ? "Re" : "",
-			      events & RUBY_EVENT_C_CALL   ? "Cc" : "",
-			      events & RUBY_EVENT_C_RETURN ? "Cr" : "",
-			      events & RUBY_EVENT_B_CALL   ? "Bc" : "",
+                              events & RUBY_EVENT_LINE     ? "Li" : "",
+                              events & RUBY_EVENT_CLASS    ? "Cl" : "",
+                              events & RUBY_EVENT_END      ? "En" : "",
+                              events & RUBY_EVENT_CALL     ? "Ca" : "",
+                              events & RUBY_EVENT_RETURN   ? "Re" : "",
+                              events & RUBY_EVENT_C_CALL   ? "Cc" : "",
+                              events & RUBY_EVENT_C_RETURN ? "Cr" : "",
+                              events & RUBY_EVENT_B_CALL   ? "Bc" : "",
                               events & RUBY_EVENT_B_RETURN ? "Br" : "",
                               events & RUBY_EVENT_COVERAGE_LINE   ? "Cli" : "",
                               events & RUBY_EVENT_COVERAGE_BRANCH ? "Cbr" : "");
-	}
+        }
     }
 
     right_strip(str);
     if (ret) {
-	rb_str_cat2(str, "\n");
-	rb_str_concat(ret, str);
+        rb_str_cat2(str, "\n");
+        rb_str_concat(ret, str);
     }
     else {
-	printf("%.*s\n", (int)RSTRING_LEN(str), RSTRING_PTR(str));
+        printf("%.*s\n", (int)RSTRING_LEN(str), RSTRING_PTR(str));
     }
     return len;
 }
@@ -2342,20 +2344,20 @@ catch_type(int type)
 {
     switch (type) {
       case CATCH_TYPE_RESCUE:
-	return "rescue";
+        return "rescue";
       case CATCH_TYPE_ENSURE:
-	return "ensure";
+        return "ensure";
       case CATCH_TYPE_RETRY:
-	return "retry";
+        return "retry";
       case CATCH_TYPE_BREAK:
-	return "break";
+        return "break";
       case CATCH_TYPE_REDO:
-	return "redo";
+        return "redo";
       case CATCH_TYPE_NEXT:
-	return "next";
+        return "next";
       default:
-	rb_bug("unknown catch type: %d", type);
-	return 0;
+        rb_bug("unknown catch type: %d", type);
+        return 0;
     }
 }
 
@@ -2364,17 +2366,17 @@ iseq_inspect(const rb_iseq_t *iseq)
 {
     const struct rb_iseq_constant_body *const body = ISEQ_BODY(iseq);
     if (!body->location.label) {
-	return rb_sprintf("#<ISeq: uninitialized>");
+        return rb_sprintf("#<ISeq: uninitialized>");
     }
     else {
-	const rb_code_location_t *loc = &body->location.code_location;
-	return rb_sprintf("#<ISeq:%"PRIsVALUE"@%"PRIsVALUE":%d (%d,%d)-(%d,%d)>",
-			  body->location.label, rb_iseq_path(iseq),
-			  loc->beg_pos.lineno,
-			  loc->beg_pos.lineno,
-			  loc->beg_pos.column,
-			  loc->end_pos.lineno,
-			  loc->end_pos.column);
+        const rb_code_location_t *loc = &body->location.code_location;
+        return rb_sprintf("#<ISeq:%"PRIsVALUE"@%"PRIsVALUE":%d (%d,%d)-(%d,%d)>",
+                          body->location.label, rb_iseq_path(iseq),
+                          loc->beg_pos.lineno,
+                          loc->beg_pos.lineno,
+                          loc->beg_pos.column,
+                          loc->end_pos.lineno,
+                          loc->end_pos.column);
     }
 }
 
@@ -2390,7 +2392,7 @@ rb_iseq_disasm_recursive(const rb_iseq_t *iseq, VALUE indent)
     const struct rb_iseq_constant_body *const body = ISEQ_BODY(iseq);
     VALUE *code;
     VALUE str = rb_str_new(0, 0);
-    VALUE child = rb_ary_tmp_new(3);
+    VALUE child = rb_ary_hidden_new(3);
     unsigned int size;
     unsigned int i;
     long l;
@@ -2410,113 +2412,113 @@ rb_iseq_disasm_recursive(const rb_iseq_t *iseq, VALUE indent)
     rb_str_cat2(str, "== disasm: ");
 
     rb_str_append(str, iseq_inspect(iseq));
-    rb_str_catf(str, " (catch: %s)", body->catch_except_p ? "TRUE" : "FALSE");
+    rb_str_catf(str, " (catch: %s)", body->catch_except_p ? "true" : "false");
     if ((l = RSTRING_LEN(str) - indent_len) < header_minlen) {
-	rb_str_modify_expand(str, header_minlen - l);
-	memset(RSTRING_END(str), '=', header_minlen - l);
+        rb_str_modify_expand(str, header_minlen - l);
+        memset(RSTRING_END(str), '=', header_minlen - l);
     }
     rb_str_cat2(str, "\n");
 
     /* show catch table information */
     if (body->catch_table) {
-	rb_str_cat(str, indent_str, indent_len);
-	rb_str_cat2(str, "== catch table\n");
+        rb_str_cat(str, indent_str, indent_len);
+        rb_str_cat2(str, "== catch table\n");
     }
     if (body->catch_table) {
-	rb_str_cat_cstr(indent, "| ");
-	indent_str = RSTRING_PTR(indent);
-	for (i = 0; i < body->catch_table->size; i++) {
-	    const struct iseq_catch_table_entry *entry =
-		UNALIGNED_MEMBER_PTR(body->catch_table, entries[i]);
-	    rb_str_cat(str, indent_str, indent_len);
-	    rb_str_catf(str,
-			"| catch type: %-6s st: %04d ed: %04d sp: %04d cont: %04d\n",
-			catch_type((int)entry->type), (int)entry->start,
-			(int)entry->end, (int)entry->sp, (int)entry->cont);
-	    if (entry->iseq && !(done_iseq && st_is_member(done_iseq, (st_data_t)entry->iseq))) {
-		rb_str_concat(str, rb_iseq_disasm_recursive(rb_iseq_check(entry->iseq), indent));
-		if (!done_iseq) {
+        rb_str_cat_cstr(indent, "| ");
+        indent_str = RSTRING_PTR(indent);
+        for (i = 0; i < body->catch_table->size; i++) {
+            const struct iseq_catch_table_entry *entry =
+                UNALIGNED_MEMBER_PTR(body->catch_table, entries[i]);
+            rb_str_cat(str, indent_str, indent_len);
+            rb_str_catf(str,
+                        "| catch type: %-6s st: %04d ed: %04d sp: %04d cont: %04d\n",
+                        catch_type((int)entry->type), (int)entry->start,
+                        (int)entry->end, (int)entry->sp, (int)entry->cont);
+            if (entry->iseq && !(done_iseq && st_is_member(done_iseq, (st_data_t)entry->iseq))) {
+                rb_str_concat(str, rb_iseq_disasm_recursive(rb_iseq_check(entry->iseq), indent));
+                if (!done_iseq) {
                     done_iseq = st_init_numtable();
                     done_iseq_wrapper = TypedData_Wrap_Struct(0, &tmp_set, done_iseq);
                 }
-		st_insert(done_iseq, (st_data_t)entry->iseq, (st_data_t)0);
-		indent_str = RSTRING_PTR(indent);
-	    }
-	}
-	rb_str_resize(indent, indent_len);
-	indent_str = RSTRING_PTR(indent);
+                st_insert(done_iseq, (st_data_t)entry->iseq, (st_data_t)0);
+                indent_str = RSTRING_PTR(indent);
+            }
+        }
+        rb_str_resize(indent, indent_len);
+        indent_str = RSTRING_PTR(indent);
     }
     if (body->catch_table) {
-	rb_str_cat(str, indent_str, indent_len);
-	rb_str_cat2(str, "|-------------------------------------"
-		    "-----------------------------------\n");
+        rb_str_cat(str, indent_str, indent_len);
+        rb_str_cat2(str, "|-------------------------------------"
+                    "-----------------------------------\n");
     }
 
     /* show local table information */
     if (body->local_table) {
-	const struct rb_iseq_param_keyword *const keyword = body->param.keyword;
-	rb_str_cat(str, indent_str, indent_len);
-	rb_str_catf(str,
-		    "local table (size: %d, argc: %d "
-		    "[opts: %d, rest: %d, post: %d, block: %d, kw: %d@%d, kwrest: %d])\n",
-		    body->local_table_size,
-		    body->param.lead_num,
-		    body->param.opt_num,
-		    body->param.flags.has_rest ? body->param.rest_start : -1,
-		    body->param.post_num,
-		    body->param.flags.has_block ? body->param.block_start : -1,
-		    body->param.flags.has_kw ? keyword->num : -1,
-		    body->param.flags.has_kw ? keyword->required_num : -1,
-		    body->param.flags.has_kwrest ? keyword->rest_start : -1);
-
-	for (i = body->local_table_size; i > 0;) {
-	    int li = body->local_table_size - --i - 1;
-	    long width;
-	    VALUE name = local_var_name(iseq, 0, i);
+        const struct rb_iseq_param_keyword *const keyword = body->param.keyword;
+        rb_str_cat(str, indent_str, indent_len);
+        rb_str_catf(str,
+                    "local table (size: %d, argc: %d "
+                    "[opts: %d, rest: %d, post: %d, block: %d, kw: %d@%d, kwrest: %d])\n",
+                    body->local_table_size,
+                    body->param.lead_num,
+                    body->param.opt_num,
+                    body->param.flags.has_rest ? body->param.rest_start : -1,
+                    body->param.post_num,
+                    body->param.flags.has_block ? body->param.block_start : -1,
+                    body->param.flags.has_kw ? keyword->num : -1,
+                    body->param.flags.has_kw ? keyword->required_num : -1,
+                    body->param.flags.has_kwrest ? keyword->rest_start : -1);
+
+        for (i = body->local_table_size; i > 0;) {
+            int li = body->local_table_size - --i - 1;
+            long width;
+            VALUE name = local_var_name(iseq, 0, i);
             char argi[0x100];
             char opti[0x100];
 
             opti[0] = '\0';
-	    if (body->param.flags.has_opt) {
-		int argc = body->param.lead_num;
-		int opts = body->param.opt_num;
-		if (li >= argc && li < argc + opts) {
-		    snprintf(opti, sizeof(opti), "Opt=%"PRIdVALUE,
-			     body->param.opt_table[li - argc]);
-		}
-	    }
-
-	    snprintf(argi, sizeof(argi), "%s%s%s%s%s%s",	/* arg, opts, rest, post, kwrest, block */
-		     body->param.lead_num > li ? "Arg" : "",
-		     opti,
-		     (body->param.flags.has_rest && body->param.rest_start == li) ? "Rest" : "",
-		     (body->param.flags.has_post && body->param.post_start <= li && li < body->param.post_start + body->param.post_num) ? "Post" : "",
-		     (body->param.flags.has_kwrest && keyword->rest_start == li) ? "Kwrest" : "",
-		     (body->param.flags.has_block && body->param.block_start == li) ? "Block" : "");
-
-	    rb_str_cat(str, indent_str, indent_len);
-	    rb_str_catf(str, "[%2d] ", i + 1);
-	    width = RSTRING_LEN(str) + 11;
-	    rb_str_append(str, name);
-	    if (*argi) rb_str_catf(str, "<%s>", argi);
-	    if ((width -= RSTRING_LEN(str)) > 0) rb_str_catf(str, "%*s", (int)width, "");
-	}
-	rb_str_cat_cstr(right_strip(str), "\n");
+            if (body->param.flags.has_opt) {
+                int argc = body->param.lead_num;
+                int opts = body->param.opt_num;
+                if (li >= argc && li < argc + opts) {
+                    snprintf(opti, sizeof(opti), "Opt=%"PRIdVALUE,
+                             body->param.opt_table[li - argc]);
+                }
+            }
+
+            snprintf(argi, sizeof(argi), "%s%s%s%s%s%s",	/* arg, opts, rest, post, kwrest, block */
+                     body->param.lead_num > li ? "Arg" : "",
+                     opti,
+                     (body->param.flags.has_rest && body->param.rest_start == li) ? "Rest" : "",
+                     (body->param.flags.has_post && body->param.post_start <= li && li < body->param.post_start + body->param.post_num) ? "Post" : "",
+                     (body->param.flags.has_kwrest && keyword->rest_start == li) ? "Kwrest" : "",
+                     (body->param.flags.has_block && body->param.block_start == li) ? "Block" : "");
+
+            rb_str_cat(str, indent_str, indent_len);
+            rb_str_catf(str, "[%2d] ", i + 1);
+            width = RSTRING_LEN(str) + 11;
+            rb_str_append(str, name);
+            if (*argi) rb_str_catf(str, "<%s>", argi);
+            if ((width -= RSTRING_LEN(str)) > 0) rb_str_catf(str, "%*s", (int)width, "");
+        }
+        rb_str_cat_cstr(right_strip(str), "\n");
     }
 
     /* show each line */
     code = rb_iseq_original_iseq(iseq);
     for (n = 0; n < size;) {
-	rb_str_cat(str, indent_str, indent_len);
-	n += rb_iseq_disasm_insn(str, code, n, iseq, child);
+        rb_str_cat(str, indent_str, indent_len);
+        n += rb_iseq_disasm_insn(str, code, n, iseq, child);
     }
 
     for (l = 0; l < RARRAY_LEN(child); l++) {
-	VALUE isv = rb_ary_entry(child, l);
-	if (done_iseq && st_is_member(done_iseq, (st_data_t)isv)) continue;
-	rb_str_cat_cstr(str, "\n");
-	rb_str_concat(str, rb_iseq_disasm_recursive(rb_iseq_check((rb_iseq_t *)isv), indent));
-	indent_str = RSTRING_PTR(indent);
+        VALUE isv = rb_ary_entry(child, l);
+        if (done_iseq && st_is_member(done_iseq, (st_data_t)isv)) continue;
+        rb_str_cat_cstr(str, "\n");
+        rb_str_concat(str, rb_iseq_disasm_recursive(rb_iseq_check((rb_iseq_t *)isv), indent));
+        indent_str = RSTRING_PTR(indent);
     }
     RB_GC_GUARD(done_iseq_wrapper);
 
@@ -2532,6 +2534,34 @@ rb_iseq_disasm(const rb_iseq_t *iseq)
 }
 
 /*
+ * Estimates the number of instance variables that will be set on
+ * a given `class` with the initialize method defined in
+ * `initialize_iseq`
+ */
+attr_index_t
+rb_estimate_iv_count(VALUE klass, const rb_iseq_t * initialize_iseq)
+{
+    struct rb_id_table * iv_names = rb_id_table_create(0);
+
+    for (unsigned int i = 0; i < ISEQ_BODY(initialize_iseq)->ivc_size; i++) {
+        IVC cache = (IVC)&ISEQ_BODY(initialize_iseq)->is_entries[i];
+
+        if (cache->iv_set_name) {
+            rb_id_table_insert(iv_names, cache->iv_set_name, Qtrue);
+        }
+    }
+
+    attr_index_t count = (attr_index_t)rb_id_table_size(iv_names);
+
+    VALUE superclass = rb_class_superclass(klass);
+    count += RCLASS_EXT(superclass)->max_iv_count;
+
+    rb_id_table_free(iv_names);
+
+    return count;
+}
+
+/*
  *  call-seq:
  *     iseq.disasm -> str
  *     iseq.disassemble -> str
@@ -2657,10 +2687,10 @@ iseqw_trace_points(VALUE self)
     VALUE ary = rb_ary_new();
 
     for (i=0; i<body->insns_info.size; i++) {
-	const struct iseq_insn_info_entry *entry = &body->insns_info.body[i];
-	if (entry->events) {
-	    push_event_info(iseq, entry->events, entry->line_no, ary);
-	}
+        const struct iseq_insn_info_entry *entry = &body->insns_info.body[i];
+        if (entry->events) {
+            push_event_info(iseq, entry->events, entry->line_no, ary);
+        }
     }
     return ary;
 }
@@ -2787,8 +2817,8 @@ ruby_node_name(int node)
     switch (node) {
 #include "node_name.inc"
       default:
-	rb_bug("unknown node: %d", node);
-	return 0;
+        rb_bug("unknown node: %d", node);
+        return 0;
     }
 }
 
@@ -2812,7 +2842,7 @@ exception_type2symbol(VALUE type)
       case CATCH_TYPE_REDO:   CONST_ID(id, "redo");   break;
       case CATCH_TYPE_NEXT:   CONST_ID(id, "next");   break;
       default:
-	rb_bug("unknown exception type: %d", (int)type);
+        rb_bug("unknown exception type: %d", (int)type);
     }
     return ID2SYM(id);
 }
@@ -2838,7 +2868,7 @@ static const rb_data_type_t label_wrapper = {
   id_##name = rb_intern(#name)
 
 static VALUE
-iseq_type_id(enum iseq_type type)
+iseq_type_id(enum rb_iseq_type type)
 {
     DECL_ID(top);
     DECL_ID(method);
@@ -2913,168 +2943,179 @@ iseq_data_to_ary(const rb_iseq_t *iseq)
 
     /* locals */
     for (i=0; i<iseq_body->local_table_size; i++) {
-	ID lid = iseq_body->local_table[i];
-	if (lid) {
-	    if (rb_id2str(lid)) {
-		rb_ary_push(locals, ID2SYM(lid));
-	    }
-	    else { /* hidden variable from id_internal() */
-		rb_ary_push(locals, ULONG2NUM(iseq_body->local_table_size-i+1));
-	    }
-	}
-	else {
-	    rb_ary_push(locals, ID2SYM(rb_intern("#arg_rest")));
-	}
+        ID lid = iseq_body->local_table[i];
+        if (lid) {
+            if (rb_id2str(lid)) {
+                rb_ary_push(locals, ID2SYM(lid));
+            }
+            else { /* hidden variable from id_internal() */
+                rb_ary_push(locals, ULONG2NUM(iseq_body->local_table_size-i+1));
+            }
+        }
+        else {
+            rb_ary_push(locals, ID2SYM(rb_intern("#arg_rest")));
+        }
     }
 
     /* params */
     {
-	const struct rb_iseq_param_keyword *const keyword = iseq_body->param.keyword;
-	int j;
-
-	if (iseq_body->param.flags.has_opt) {
-	    int len = iseq_body->param.opt_num + 1;
-	    VALUE arg_opt_labels = rb_ary_new2(len);
-
-	    for (j = 0; j < len; j++) {
-		VALUE l = register_label(labels_table, iseq_body->param.opt_table[j]);
-		rb_ary_push(arg_opt_labels, l);
-	    }
-	    rb_hash_aset(params, ID2SYM(rb_intern("opt")), arg_opt_labels);
-        }
-
-	/* commit */
-	if (iseq_body->param.flags.has_lead) rb_hash_aset(params, ID2SYM(rb_intern("lead_num")), INT2FIX(iseq_body->param.lead_num));
-	if (iseq_body->param.flags.has_post) rb_hash_aset(params, ID2SYM(rb_intern("post_num")), INT2FIX(iseq_body->param.post_num));
-	if (iseq_body->param.flags.has_post) rb_hash_aset(params, ID2SYM(rb_intern("post_start")), INT2FIX(iseq_body->param.post_start));
-	if (iseq_body->param.flags.has_rest) rb_hash_aset(params, ID2SYM(rb_intern("rest_start")), INT2FIX(iseq_body->param.rest_start));
-	if (iseq_body->param.flags.has_block) rb_hash_aset(params, ID2SYM(rb_intern("block_start")), INT2FIX(iseq_body->param.block_start));
-	if (iseq_body->param.flags.has_kw) {
-	    VALUE keywords = rb_ary_new();
-	    int i, j;
-	    for (i=0; i<keyword->required_num; i++) {
-		rb_ary_push(keywords, ID2SYM(keyword->table[i]));
-	    }
-	    for (j=0; i<keyword->num; i++, j++) {
-		VALUE key = rb_ary_new_from_args(1, ID2SYM(keyword->table[i]));
-		if (keyword->default_values[j] != Qundef) {
-		    rb_ary_push(key, keyword->default_values[j]);
-		}
-		rb_ary_push(keywords, key);
-	    }
-
-	    rb_hash_aset(params, ID2SYM(rb_intern("kwbits")),
-	                 INT2FIX(keyword->bits_start));
-	    rb_hash_aset(params, ID2SYM(rb_intern("keyword")), keywords);
-	}
-	if (iseq_body->param.flags.has_kwrest) rb_hash_aset(params, ID2SYM(rb_intern("kwrest")), INT2FIX(keyword->rest_start));
-	if (iseq_body->param.flags.ambiguous_param0) rb_hash_aset(params, ID2SYM(rb_intern("ambiguous_param0")), Qtrue);
+        const struct rb_iseq_param_keyword *const keyword = iseq_body->param.keyword;
+        int j;
+
+        if (iseq_body->param.flags.has_opt) {
+            int len = iseq_body->param.opt_num + 1;
+            VALUE arg_opt_labels = rb_ary_new2(len);
+
+            for (j = 0; j < len; j++) {
+                VALUE l = register_label(labels_table, iseq_body->param.opt_table[j]);
+                rb_ary_push(arg_opt_labels, l);
+            }
+            rb_hash_aset(params, ID2SYM(rb_intern("opt")), arg_opt_labels);
+        }
+
+        /* commit */
+        if (iseq_body->param.flags.has_lead) rb_hash_aset(params, ID2SYM(rb_intern("lead_num")), INT2FIX(iseq_body->param.lead_num));
+        if (iseq_body->param.flags.has_post) rb_hash_aset(params, ID2SYM(rb_intern("post_num")), INT2FIX(iseq_body->param.post_num));
+        if (iseq_body->param.flags.has_post) rb_hash_aset(params, ID2SYM(rb_intern("post_start")), INT2FIX(iseq_body->param.post_start));
+        if (iseq_body->param.flags.has_rest) rb_hash_aset(params, ID2SYM(rb_intern("rest_start")), INT2FIX(iseq_body->param.rest_start));
+        if (iseq_body->param.flags.has_block) rb_hash_aset(params, ID2SYM(rb_intern("block_start")), INT2FIX(iseq_body->param.block_start));
+        if (iseq_body->param.flags.has_kw) {
+            VALUE keywords = rb_ary_new();
+            int i, j;
+            for (i=0; i<keyword->required_num; i++) {
+                rb_ary_push(keywords, ID2SYM(keyword->table[i]));
+            }
+            for (j=0; i<keyword->num; i++, j++) {
+                VALUE key = rb_ary_new_from_args(1, ID2SYM(keyword->table[i]));
+                if (!UNDEF_P(keyword->default_values[j])) {
+                    rb_ary_push(key, keyword->default_values[j]);
+                }
+                rb_ary_push(keywords, key);
+            }
+
+            rb_hash_aset(params, ID2SYM(rb_intern("kwbits")),
+                         INT2FIX(keyword->bits_start));
+            rb_hash_aset(params, ID2SYM(rb_intern("keyword")), keywords);
+        }
+        if (iseq_body->param.flags.has_kwrest) rb_hash_aset(params, ID2SYM(rb_intern("kwrest")), INT2FIX(keyword->rest_start));
+        if (iseq_body->param.flags.ambiguous_param0) rb_hash_aset(params, ID2SYM(rb_intern("ambiguous_param0")), Qtrue);
     }
 
     /* body */
     iseq_original = rb_iseq_original_iseq((rb_iseq_t *)iseq);
 
     for (seq = iseq_original; seq < iseq_original + iseq_body->iseq_size; ) {
-	VALUE insn = *seq++;
-	int j, len = insn_len(insn);
-	VALUE *nseq = seq + len - 1;
-	VALUE ary = rb_ary_new2(len);
+        VALUE insn = *seq++;
+        int j, len = insn_len(insn);
+        VALUE *nseq = seq + len - 1;
+        VALUE ary = rb_ary_new2(len);
 
         rb_ary_push(ary, ID2SYM(insn_syms[insn%numberof(insn_syms)]));
-	for (j=0; j<len-1; j++, seq++) {
-	    switch (insn_op_type(insn, j)) {
-	      case TS_OFFSET: {
-		unsigned long idx = nseq - iseq_original + *seq;
-		rb_ary_push(ary, register_label(labels_table, idx));
-		break;
-	      }
-	      case TS_LINDEX:
-	      case TS_NUM:
-		rb_ary_push(ary, INT2FIX(*seq));
-		break;
-	      case TS_VALUE:
-		rb_ary_push(ary, obj_resurrect(*seq));
-		break;
-	      case TS_ISEQ:
-		{
-		    const rb_iseq_t *iseq = (rb_iseq_t *)*seq;
-		    if (iseq) {
-			VALUE val = iseq_data_to_ary(rb_iseq_check(iseq));
-			rb_ary_push(ary, val);
-		    }
-		    else {
-			rb_ary_push(ary, Qnil);
-		    }
-		}
-		break;
-	      case TS_IC:
+        for (j=0; j<len-1; j++, seq++) {
+            enum ruby_insn_type_chars op_type = insn_op_type(insn, j);
+
+            switch (op_type) {
+              case TS_OFFSET: {
+                unsigned long idx = nseq - iseq_original + *seq;
+                rb_ary_push(ary, register_label(labels_table, idx));
+                break;
+              }
+              case TS_LINDEX:
+              case TS_NUM:
+                rb_ary_push(ary, INT2FIX(*seq));
+                break;
+              case TS_VALUE:
+                rb_ary_push(ary, obj_resurrect(*seq));
+                break;
+              case TS_ISEQ:
+                {
+                    const rb_iseq_t *iseq = (rb_iseq_t *)*seq;
+                    if (iseq) {
+                        VALUE val = iseq_data_to_ary(rb_iseq_check(iseq));
+                        rb_ary_push(ary, val);
+                    }
+                    else {
+                        rb_ary_push(ary, Qnil);
+                    }
+                }
+                break;
+              case TS_IC:
+                {
+                    VALUE list = rb_ary_new();
+                    const ID *ids = ((IC)*seq)->segments;
+                    while (*ids) {
+                        rb_ary_push(list, ID2SYM(*ids++));
+                    }
+                    rb_ary_push(ary, list);
+                }
+                break;
               case TS_IVC:
               case TS_ICVARC:
-	      case TS_ISE:
-		{
-		    union iseq_inline_storage_entry *is = (union iseq_inline_storage_entry *)*seq;
-		    rb_ary_push(ary, INT2FIX(is - iseq_body->is_entries));
-		}
-		break;
+              case TS_ISE:
+                {
+                    union iseq_inline_storage_entry *is = (union iseq_inline_storage_entry *)*seq;
+                    rb_ary_push(ary, INT2FIX(is - ISEQ_IS_ENTRY_START(ISEQ_BODY(iseq), op_type)));
+                }
+                break;
               case TS_CALLDATA:
-		{
+                {
                     struct rb_call_data *cd = (struct rb_call_data *)*seq;
                     const struct rb_callinfo *ci = cd->ci;
-		    VALUE e = rb_hash_new();
+                    VALUE e = rb_hash_new();
                     int argc = vm_ci_argc(ci);
 
                     ID mid = vm_ci_mid(ci);
-		    rb_hash_aset(e, ID2SYM(rb_intern("mid")), mid ? ID2SYM(mid) : Qnil);
-		    rb_hash_aset(e, ID2SYM(rb_intern("flag")), UINT2NUM(vm_ci_flag(ci)));
+                    rb_hash_aset(e, ID2SYM(rb_intern("mid")), mid ? ID2SYM(mid) : Qnil);
+                    rb_hash_aset(e, ID2SYM(rb_intern("flag")), UINT2NUM(vm_ci_flag(ci)));
 
                     if (vm_ci_flag(ci) & VM_CALL_KWARG) {
                         const struct rb_callinfo_kwarg *kwarg = vm_ci_kwarg(ci);
                         int i;
-			VALUE kw = rb_ary_new2((long)kwarg->keyword_len);
+                        VALUE kw = rb_ary_new2((long)kwarg->keyword_len);
 
-			argc -= kwarg->keyword_len;
+                        argc -= kwarg->keyword_len;
                         for (i = 0; i < kwarg->keyword_len; i++) {
-			    rb_ary_push(kw, kwarg->keywords[i]);
-			}
-			rb_hash_aset(e, ID2SYM(rb_intern("kw_arg")), kw);
-		    }
-
-		    rb_hash_aset(e, ID2SYM(rb_intern("orig_argc")),
-				INT2FIX(argc));
-		    rb_ary_push(ary, e);
-	        }
-		break;
-	      case TS_ID:
-		rb_ary_push(ary, ID2SYM(*seq));
-		break;
-	      case TS_CDHASH:
-		{
-		    VALUE hash = *seq;
-		    VALUE val = rb_ary_new();
-		    int i;
-
-		    rb_hash_foreach(hash, cdhash_each, val);
-
-		    for (i=0; i<RARRAY_LEN(val); i+=2) {
-			VALUE pos = FIX2INT(rb_ary_entry(val, i+1));
-			unsigned long idx = nseq - iseq_original + pos;
-
-			rb_ary_store(val, i+1,
-				     register_label(labels_table, idx));
-		    }
-		    rb_ary_push(ary, val);
-		}
-		break;
-	      case TS_FUNCPTR:
-		{
+                            rb_ary_push(kw, kwarg->keywords[i]);
+                        }
+                        rb_hash_aset(e, ID2SYM(rb_intern("kw_arg")), kw);
+                    }
+
+                    rb_hash_aset(e, ID2SYM(rb_intern("orig_argc")),
+                                INT2FIX(argc));
+                    rb_ary_push(ary, e);
+                }
+                break;
+              case TS_ID:
+                rb_ary_push(ary, ID2SYM(*seq));
+                break;
+              case TS_CDHASH:
+                {
+                    VALUE hash = *seq;
+                    VALUE val = rb_ary_new();
+                    int i;
+
+                    rb_hash_foreach(hash, cdhash_each, val);
+
+                    for (i=0; i<RARRAY_LEN(val); i+=2) {
+                        VALUE pos = FIX2INT(rb_ary_entry(val, i+1));
+                        unsigned long idx = nseq - iseq_original + pos;
+
+                        rb_ary_store(val, i+1,
+                                     register_label(labels_table, idx));
+                    }
+                    rb_ary_push(ary, val);
+                }
+                break;
+              case TS_FUNCPTR:
+                {
 #if SIZEOF_VALUE <= SIZEOF_LONG
-		    VALUE val = LONG2NUM((SIGNED_VALUE)*seq);
+                    VALUE val = LONG2NUM((SIGNED_VALUE)*seq);
 #else
-		    VALUE val = LL2NUM((SIGNED_VALUE)*seq);
+                    VALUE val = LL2NUM((SIGNED_VALUE)*seq);
 #endif
-		    rb_ary_push(ary, val);
-		}
-		break;
+                    rb_ary_push(ary, val);
+                }
+                break;
               case TS_BUILTIN:
                 {
                     VALUE val = rb_hash_new();
@@ -3090,32 +3131,32 @@ iseq_data_to_ary(const rb_iseq_t *iseq)
                     rb_ary_push(ary, val);
                 }
                 break;
-	      default:
-		rb_bug("unknown operand: %c", insn_op_type(insn, j));
-	    }
-	}
-	rb_ary_push(body, ary);
+              default:
+                rb_bug("unknown operand: %c", insn_op_type(insn, j));
+            }
+        }
+        rb_ary_push(body, ary);
     }
 
     nbody = body;
 
     /* exception */
     if (iseq_body->catch_table) for (i=0; i<iseq_body->catch_table->size; i++) {
-	VALUE ary = rb_ary_new();
-	const struct iseq_catch_table_entry *entry =
-	    UNALIGNED_MEMBER_PTR(iseq_body->catch_table, entries[i]);
-	rb_ary_push(ary, exception_type2symbol(entry->type));
-	if (entry->iseq) {
-	    rb_ary_push(ary, iseq_data_to_ary(rb_iseq_check(entry->iseq)));
-	}
-	else {
-	    rb_ary_push(ary, Qnil);
-	}
-	rb_ary_push(ary, register_label(labels_table, entry->start));
-	rb_ary_push(ary, register_label(labels_table, entry->end));
-	rb_ary_push(ary, register_label(labels_table, entry->cont));
-	rb_ary_push(ary, UINT2NUM(entry->sp));
-	rb_ary_push(exception, ary);
+        VALUE ary = rb_ary_new();
+        const struct iseq_catch_table_entry *entry =
+            UNALIGNED_MEMBER_PTR(iseq_body->catch_table, entries[i]);
+        rb_ary_push(ary, exception_type2symbol(entry->type));
+        if (entry->iseq) {
+            rb_ary_push(ary, iseq_data_to_ary(rb_iseq_check(entry->iseq)));
+        }
+        else {
+            rb_ary_push(ary, Qnil);
+        }
+        rb_ary_push(ary, register_label(labels_table, entry->start));
+        rb_ary_push(ary, register_label(labels_table, entry->end));
+        rb_ary_push(ary, register_label(labels_table, entry->cont));
+        rb_ary_push(ary, UINT2NUM(entry->sp));
+        rb_ary_push(exception, ary);
     }
 
     /* make body with labels and insert line number */
@@ -3126,41 +3167,41 @@ iseq_data_to_ary(const rb_iseq_t *iseq)
 #endif
 
     for (l=0, pos=0; l<RARRAY_LEN(nbody); l++) {
-	const struct iseq_insn_info_entry *info;
-	VALUE ary = RARRAY_AREF(nbody, l);
-	st_data_t label;
+        const struct iseq_insn_info_entry *info;
+        VALUE ary = RARRAY_AREF(nbody, l);
+        st_data_t label;
 
-	if (st_lookup(labels_table, pos, &label)) {
-	    rb_ary_push(body, (VALUE)label);
-	}
+        if (st_lookup(labels_table, pos, &label)) {
+            rb_ary_push(body, (VALUE)label);
+        }
 
-	info = get_insn_info(iseq, pos);
+        info = get_insn_info(iseq, pos);
 #ifdef USE_ISEQ_NODE_ID
         rb_ary_push(node_ids, INT2FIX(info->node_id));
 #endif
 
-	if (prev_insn_info != info) {
-	    int line = info->line_no;
-	    rb_event_flag_t events = info->events;
+        if (prev_insn_info != info) {
+            int line = info->line_no;
+            rb_event_flag_t events = info->events;
 
-	    if (line > 0 && last_line != line) {
-		rb_ary_push(body, INT2FIX(line));
-		last_line = line;
-	    }
+            if (line > 0 && last_line != line) {
+                rb_ary_push(body, INT2FIX(line));
+                last_line = line;
+            }
 #define CHECK_EVENT(ev) if (events & ev) rb_ary_push(body, ID2SYM(rb_intern(#ev)));
-	    CHECK_EVENT(RUBY_EVENT_LINE);
-	    CHECK_EVENT(RUBY_EVENT_CLASS);
-	    CHECK_EVENT(RUBY_EVENT_END);
-	    CHECK_EVENT(RUBY_EVENT_CALL);
-	    CHECK_EVENT(RUBY_EVENT_RETURN);
-	    CHECK_EVENT(RUBY_EVENT_B_CALL);
-	    CHECK_EVENT(RUBY_EVENT_B_RETURN);
+            CHECK_EVENT(RUBY_EVENT_LINE);
+            CHECK_EVENT(RUBY_EVENT_CLASS);
+            CHECK_EVENT(RUBY_EVENT_END);
+            CHECK_EVENT(RUBY_EVENT_CALL);
+            CHECK_EVENT(RUBY_EVENT_RETURN);
+            CHECK_EVENT(RUBY_EVENT_B_CALL);
+            CHECK_EVENT(RUBY_EVENT_B_RETURN);
 #undef CHECK_EVENT
-	    prev_insn_info = info;
-	}
+            prev_insn_info = info;
+        }
 
-	rb_ary_push(body, ary);
-	pos += RARRAY_LENINT(ary); /* reject too huge data */
+        rb_ary_push(body, ary);
+        pos += RARRAY_LENINT(ary); /* reject too huge data */
     }
     RB_GC_GUARD(nbody);
     RB_GC_GUARD(labels_wrapper);
@@ -3170,11 +3211,11 @@ iseq_data_to_ary(const rb_iseq_t *iseq)
     rb_hash_aset(misc, ID2SYM(rb_intern("stack_max")), INT2FIX(iseq_body->stack_max));
     rb_hash_aset(misc, ID2SYM(rb_intern("node_id")), INT2FIX(iseq_body->location.node_id));
     rb_hash_aset(misc, ID2SYM(rb_intern("code_location")),
-	    rb_ary_new_from_args(4,
-		INT2FIX(iseq_body->location.code_location.beg_pos.lineno),
-		INT2FIX(iseq_body->location.code_location.beg_pos.column),
-		INT2FIX(iseq_body->location.code_location.end_pos.lineno),
-		INT2FIX(iseq_body->location.code_location.end_pos.column)));
+            rb_ary_new_from_args(4,
+                INT2FIX(iseq_body->location.code_location.beg_pos.lineno),
+                INT2FIX(iseq_body->location.code_location.beg_pos.column),
+                INT2FIX(iseq_body->location.code_location.end_pos.lineno),
+                INT2FIX(iseq_body->location.code_location.end_pos.column)));
 #ifdef USE_ISEQ_NODE_ID
     rb_hash_aset(misc, ID2SYM(rb_intern("node_ids")), node_ids);
 #endif
@@ -3192,7 +3233,7 @@ iseq_data_to_ary(const rb_iseq_t *iseq)
     rb_ary_push(val, iseq_body->location.label);
     rb_ary_push(val, rb_iseq_path(iseq));
     rb_ary_push(val, rb_iseq_realpath(iseq));
-    rb_ary_push(val, iseq_body->location.first_lineno);
+    rb_ary_push(val, RB_INT2NUM(iseq_body->location.first_lineno));
     rb_ary_push(val, ID2SYM(type));
     rb_ary_push(val, locals);
     rb_ary_push(val, params);
@@ -3212,81 +3253,81 @@ rb_iseq_parameters(const rb_iseq_t *iseq, int is_proc)
 #define PARAM_TYPE(type) rb_ary_push(a = rb_ary_new2(2), ID2SYM(type))
 #define PARAM_ID(i) body->local_table[(i)]
 #define PARAM(i, type) (		      \
-	PARAM_TYPE(type),		      \
-	rb_id2str(PARAM_ID(i)) ?	      \
-	rb_ary_push(a, ID2SYM(PARAM_ID(i))) : \
-	a)
+        PARAM_TYPE(type),		      \
+        rb_id2str(PARAM_ID(i)) ?	      \
+        rb_ary_push(a, ID2SYM(PARAM_ID(i))) : \
+        a)
 
     CONST_ID(req, "req");
     CONST_ID(opt, "opt");
     if (is_proc) {
-	for (i = 0; i < body->param.lead_num; i++) {
-	    PARAM_TYPE(opt);
-	    rb_ary_push(a, rb_id2str(PARAM_ID(i)) ? ID2SYM(PARAM_ID(i)) : Qnil);
-	    rb_ary_push(args, a);
-	}
+        for (i = 0; i < body->param.lead_num; i++) {
+            PARAM_TYPE(opt);
+            rb_ary_push(a, rb_id2str(PARAM_ID(i)) ? ID2SYM(PARAM_ID(i)) : Qnil);
+            rb_ary_push(args, a);
+        }
     }
     else {
-	for (i = 0; i < body->param.lead_num; i++) {
-	    rb_ary_push(args, PARAM(i, req));
-	}
+        for (i = 0; i < body->param.lead_num; i++) {
+            rb_ary_push(args, PARAM(i, req));
+        }
     }
     r = body->param.lead_num + body->param.opt_num;
     for (; i < r; i++) {
-	PARAM_TYPE(opt);
-	if (rb_id2str(PARAM_ID(i))) {
-	    rb_ary_push(a, ID2SYM(PARAM_ID(i)));
-	}
-	rb_ary_push(args, a);
+        PARAM_TYPE(opt);
+        if (rb_id2str(PARAM_ID(i))) {
+            rb_ary_push(a, ID2SYM(PARAM_ID(i)));
+        }
+        rb_ary_push(args, a);
     }
     if (body->param.flags.has_rest) {
-	CONST_ID(rest, "rest");
-	rb_ary_push(args, PARAM(body->param.rest_start, rest));
+        CONST_ID(rest, "rest");
+        rb_ary_push(args, PARAM(body->param.rest_start, rest));
     }
     r = body->param.post_start + body->param.post_num;
     if (is_proc) {
-	for (i = body->param.post_start; i < r; i++) {
-	    PARAM_TYPE(opt);
-	    rb_ary_push(a, rb_id2str(PARAM_ID(i)) ? ID2SYM(PARAM_ID(i)) : Qnil);
-	    rb_ary_push(args, a);
-	}
+        for (i = body->param.post_start; i < r; i++) {
+            PARAM_TYPE(opt);
+            rb_ary_push(a, rb_id2str(PARAM_ID(i)) ? ID2SYM(PARAM_ID(i)) : Qnil);
+            rb_ary_push(args, a);
+        }
     }
     else {
-	for (i = body->param.post_start; i < r; i++) {
-	    rb_ary_push(args, PARAM(i, req));
-	}
+        for (i = body->param.post_start; i < r; i++) {
+            rb_ary_push(args, PARAM(i, req));
+        }
     }
     if (body->param.flags.accepts_no_kwarg) {
-	ID nokey;
-	CONST_ID(nokey, "nokey");
-	PARAM_TYPE(nokey);
-	rb_ary_push(args, a);
+        ID nokey;
+        CONST_ID(nokey, "nokey");
+        PARAM_TYPE(nokey);
+        rb_ary_push(args, a);
     }
     if (body->param.flags.has_kw) {
-	i = 0;
-	if (keyword->required_num > 0) {
-	    ID keyreq;
-	    CONST_ID(keyreq, "keyreq");
-	    for (; i < keyword->required_num; i++) {
-		PARAM_TYPE(keyreq);
-		if (rb_id2str(keyword->table[i])) {
-		    rb_ary_push(a, ID2SYM(keyword->table[i]));
-		}
-		rb_ary_push(args, a);
-	    }
-	}
-	CONST_ID(key, "key");
-	for (; i < keyword->num; i++) {
-	    PARAM_TYPE(key);
-	    if (rb_id2str(keyword->table[i])) {
-		rb_ary_push(a, ID2SYM(keyword->table[i]));
-	    }
-	    rb_ary_push(args, a);
-	}
+        i = 0;
+        if (keyword->required_num > 0) {
+            ID keyreq;
+            CONST_ID(keyreq, "keyreq");
+            for (; i < keyword->required_num; i++) {
+                PARAM_TYPE(keyreq);
+                if (rb_id2str(keyword->table[i])) {
+                    rb_ary_push(a, ID2SYM(keyword->table[i]));
+                }
+                rb_ary_push(args, a);
+            }
+        }
+        CONST_ID(key, "key");
+        for (; i < keyword->num; i++) {
+            PARAM_TYPE(key);
+            if (rb_id2str(keyword->table[i])) {
+                rb_ary_push(a, ID2SYM(keyword->table[i]));
+            }
+            rb_ary_push(args, a);
+        }
     }
     if (body->param.flags.has_kwrest || body->param.flags.ruby2_keywords) {
         ID param;
-	CONST_ID(keyrest, "keyrest");
+        CONST_ID(keyrest, "keyrest");
         PARAM_TYPE(keyrest);
         if (body->param.flags.has_kwrest &&
             rb_id2str(param = PARAM_ID(keyword->rest_start))) {
@@ -3295,11 +3336,11 @@ rb_iseq_parameters(const rb_iseq_t *iseq, int is_proc)
         else if (body->param.flags.ruby2_keywords) {
             rb_ary_push(a, ID2SYM(idPow));
         }
-	rb_ary_push(args, a);
+        rb_ary_push(args, a);
     }
     if (body->param.flags.has_block) {
-	CONST_ID(block, "block");
-	rb_ary_push(args, PARAM(body->param.block_start, block));
+        CONST_ID(block, "block");
+        rb_ary_push(args, PARAM(body->param.block_start, block));
     }
     return args;
 }
@@ -3308,20 +3349,20 @@ VALUE
 rb_iseq_defined_string(enum defined_type type)
 {
     static const char expr_names[][18] = {
-	"nil",
-	"instance-variable",
-	"local-variable",
-	"global-variable",
-	"class variable",
-	"constant",
-	"method",
-	"yield",
-	"super",
-	"self",
-	"true",
-	"false",
-	"assignment",
-	"expression",
+        "nil",
+        "instance-variable",
+        "local-variable",
+        "global-variable",
+        "class variable",
+        "constant",
+        "method",
+        "yield",
+        "super",
+        "self",
+        "true",
+        "false",
+        "assignment",
+        "expression",
     };
     const char *estr;
 
@@ -3349,7 +3390,7 @@ rb_vm_encoded_insn_data_table_init(void)
     const void * const *table = rb_vm_get_insns_address_table();
 #define INSN_CODE(insn) ((VALUE)table[insn])
 #else
-#define INSN_CODE(insn) (insn)
+#define INSN_CODE(insn) ((VALUE)(insn))
 #endif
     st_data_t insn;
     encoded_insn_data = st_init_numtable_with_size(VM_INSTRUCTION_SIZE / 2);
@@ -3591,17 +3632,17 @@ void
 rb_iseq_trace_set(const rb_iseq_t *iseq, rb_event_flag_t turnon_events)
 {
     if (iseq->aux.exec.global_trace_events == turnon_events) {
-	return;
+        return;
     }
 
     if (!ISEQ_EXECUTABLE_P(iseq)) {
-	/* this is building ISeq */
-	return;
+        /* this is building ISeq */
+        return;
     }
     else {
         unsigned int pc;
         const struct rb_iseq_constant_body *const body = ISEQ_BODY(iseq);
-	VALUE *iseq_encoded = (VALUE *)body->iseq_encoded;
+        VALUE *iseq_encoded = (VALUE *)body->iseq_encoded;
         rb_event_flag_t enabled_events;
         rb_event_flag_t local_events = iseq->aux.exec.local_hooks ? iseq->aux.exec.local_hooks->events : 0;
         ((rb_iseq_t *)iseq)->aux.exec.global_trace_events = turnon_events;
@@ -3610,7 +3651,7 @@ rb_iseq_trace_set(const rb_iseq_t *iseq, rb_event_flag_t turnon_events)
         for (pc=0; pc<body->iseq_size;) {
             rb_event_flag_t pc_events = rb_iseq_event_flags(iseq, pc);
             pc += encoded_iseq_trace_instrument(&iseq_encoded[pc], pc_events & enabled_events, true);
-	}
+        }
     }
 }
 
@@ -3650,9 +3691,9 @@ trace_set_i(void *vstart, void *vend, size_t stride, void *data)
         void *ptr = asan_poisoned_object_p(v);
         asan_unpoison_object(v, false);
 
-	if (rb_obj_is_iseq(v)) {
-	    rb_iseq_trace_set(rb_iseq_check((rb_iseq_t *)v), turnon_events);
-	}
+        if (rb_obj_is_iseq(v)) {
+            rb_iseq_trace_set(rb_iseq_check((rb_iseq_t *)v), turnon_events);
+        }
         else if (imemo_type_p(v, imemo_callcache) && rb_vm_call_ivar_attrset_p(((const struct rb_callcache *)v)->call_)) {
             rb_vm_cc_general((struct rb_callcache *)v);
         }
@@ -3767,9 +3808,9 @@ iseqw_s_load_from_binary_extra_data(VALUE self, VALUE str)
 struct succ_index_table {
     uint64_t imm_part[IMMEDIATE_TABLE_SIZE / 9];
     struct succ_dict_block {
-	unsigned int rank;
-	uint64_t small_block_ranks; /* 9 bits * 7 = 63 bits */
-	uint64_t bits[512/64];
+        unsigned int rank;
+        uint64_t small_block_ranks; /* 9 bits * 7 = 63 bits */
+        uint64_t bits[512/64];
     } succ_part[FLEX_ARY_LEN];
 };
 
@@ -3791,27 +3832,27 @@ succ_index_table_create(int max_pos, int *data, int size)
 
     r = 0;
     for (j = 0; j < imm_size; j++) {
-	for (i = 0; i < 9; i++) {
-	    if (r < size && data[r] == j * 9 + i) r++;
-	    imm_block_rank_set(sd->imm_part[j], i, r);
-	}
+        for (i = 0; i < 9; i++) {
+            if (r < size && data[r] == j * 9 + i) r++;
+            imm_block_rank_set(sd->imm_part[j], i, r);
+        }
     }
     for (k = 0; k < succ_size; k++) {
-	struct succ_dict_block *sd_block = &sd->succ_part[k];
-	int small_rank = 0;
-	sd_block->rank = r;
-	for (j = 0; j < 8; j++) {
-	    uint64_t bits = 0;
-	    if (j) small_block_rank_set(sd_block->small_block_ranks, j, small_rank);
-	    for (i = 0; i < 64; i++) {
-		if (r < size && data[r] == k * 512 + j * 64 + i + IMMEDIATE_TABLE_SIZE) {
-		    bits |= ((uint64_t)1) << i;
-		    r++;
-		}
-	    }
-	    sd_block->bits[j] = bits;
-	    small_rank += rb_popcount64(bits);
-	}
+        struct succ_dict_block *sd_block = &sd->succ_part[k];
+        int small_rank = 0;
+        sd_block->rank = r;
+        for (j = 0; j < 8; j++) {
+            uint64_t bits = 0;
+            if (j) small_block_rank_set(sd_block->small_block_ranks, j, small_rank);
+            for (i = 0; i < 64; i++) {
+                if (r < size && data[r] == k * 512 + j * 64 + i + IMMEDIATE_TABLE_SIZE) {
+                    bits |= ((uint64_t)1) << i;
+                    r++;
+                }
+            }
+            sd_block->bits[j] = bits;
+            small_rank += rb_popcount64(bits);
+        }
     }
     return sd;
 }
@@ -3825,20 +3866,20 @@ succ_index_table_invert(int max_pos, struct succ_index_table *sd, int size)
     int i, j, k, r = -1;
     p = positions;
     for (j = 0; j < imm_size; j++) {
-	for (i = 0; i < 9; i++) {
-	    int nr = imm_block_rank_get(sd->imm_part[j], i);
-	    if (r != nr) *p++ = j * 9 + i;
-	    r = nr;
-	}
+        for (i = 0; i < 9; i++) {
+            int nr = imm_block_rank_get(sd->imm_part[j], i);
+            if (r != nr) *p++ = j * 9 + i;
+            r = nr;
+        }
     }
     for (k = 0; k < succ_size; k++) {
-	for (j = 0; j < 8; j++) {
-	    for (i = 0; i < 64; i++) {
-		if (sd->succ_part[k].bits[j] & (((uint64_t)1) << i)) {
-		    *p++ = k * 512 + j * 64 + i + IMMEDIATE_TABLE_SIZE;
-		}
-	    }
-	}
+        for (j = 0; j < 8; j++) {
+            for (i = 0; i < 64; i++) {
+                if (sd->succ_part[k].bits[j] & (((uint64_t)1) << i)) {
+                    *p++ = k * 512 + j * 64 + i + IMMEDIATE_TABLE_SIZE;
+                }
+            }
+        }
     }
     return positions;
 }
@@ -3847,19 +3888,19 @@ static int
 succ_index_lookup(const struct succ_index_table *sd, int x)
 {
     if (x < IMMEDIATE_TABLE_SIZE) {
-	const int i = x / 9;
-	const int j = x % 9;
-	return imm_block_rank_get(sd->imm_part[i], j);
+        const int i = x / 9;
+        const int j = x % 9;
+        return imm_block_rank_get(sd->imm_part[i], j);
     }
     else {
-	const int block_index = (x - IMMEDIATE_TABLE_SIZE) / 512;
-	const struct succ_dict_block *block = &sd->succ_part[block_index];
-	const int block_bit_index = (x - IMMEDIATE_TABLE_SIZE) % 512;
-	const int small_block_index = block_bit_index / 64;
-	const int small_block_popcount = small_block_rank_get(block->small_block_ranks, small_block_index);
-	const int popcnt = rb_popcount64(block->bits[small_block_index] << (63 - block_bit_index % 64));
-
-	return block->rank + small_block_popcount + popcnt;
+        const int block_index = (x - IMMEDIATE_TABLE_SIZE) / 512;
+        const struct succ_dict_block *block = &sd->succ_part[block_index];
+        const int block_bit_index = (x - IMMEDIATE_TABLE_SIZE) % 512;
+        const int small_block_index = block_bit_index / 64;
+        const int small_block_popcount = small_block_rank_get(block->small_block_ranks, small_block_index);
+        const int popcnt = rb_popcount64(block->bits[small_block_index] << (63 - block_bit_index % 64));
+
+        return block->rank + small_block_popcount + popcnt;
     }
 }
 #endif
diff --git a/iseq.h b/iseq.h
index a7d542fa09..2f83e7336d 100644
--- a/iseq.h
+++ b/iseq.h
@@ -17,6 +17,12 @@ RUBY_EXTERN const int ruby_api_version[];
 #define ISEQ_MAJOR_VERSION ((unsigned int)ruby_api_version[0])
 #define ISEQ_MINOR_VERSION ((unsigned int)ruby_api_version[1])
 
+#define ISEQ_MBITS_SIZE sizeof(iseq_bits_t)
+#define ISEQ_MBITS_BITLENGTH (ISEQ_MBITS_SIZE * CHAR_BIT)
+#define ISEQ_MBITS_SET(buf, i) (buf[(i) / ISEQ_MBITS_BITLENGTH] |= ((iseq_bits_t)1 << ((i) % ISEQ_MBITS_BITLENGTH)))
+#define ISEQ_MBITS_SET_P(buf, i) ((buf[(i) / ISEQ_MBITS_BITLENGTH] >> ((i) % ISEQ_MBITS_BITLENGTH)) & 0x1)
+#define ISEQ_MBITS_BUFLEN(size) roomof(size, ISEQ_MBITS_BITLENGTH)
+
 #ifndef USE_ISEQ_NODE_ID
 #define USE_ISEQ_NODE_ID 1
 #endif
@@ -25,6 +31,7 @@ RUBY_EXTERN const int ruby_api_version[];
 typedef struct rb_iseq_struct rb_iseq_t;
 #define rb_iseq_t rb_iseq_t
 #endif
+typedef void (*rb_iseq_callback)(const rb_iseq_t *, void *);
 
 extern const ID rb_iseq_shared_exc_local_tbl[];
 
@@ -70,21 +77,20 @@ ISEQ_ORIGINAL_ISEQ_ALLOC(const rb_iseq_t *iseq, long size)
 }
 
 #define ISEQ_TRACE_EVENTS (RUBY_EVENT_LINE  | \
-			   RUBY_EVENT_CLASS | \
-			   RUBY_EVENT_END   | \
-			   RUBY_EVENT_CALL  | \
-			   RUBY_EVENT_RETURN| \
+                           RUBY_EVENT_CLASS | \
+                           RUBY_EVENT_END   | \
+                           RUBY_EVENT_CALL  | \
+                           RUBY_EVENT_RETURN| \
                            RUBY_EVENT_C_CALL| \
                            RUBY_EVENT_C_RETURN| \
-			   RUBY_EVENT_B_CALL| \
-			   RUBY_EVENT_B_RETURN| \
+                           RUBY_EVENT_B_CALL| \
+                           RUBY_EVENT_B_RETURN| \
                            RUBY_EVENT_COVERAGE_LINE| \
                            RUBY_EVENT_COVERAGE_BRANCH)
 
 #define ISEQ_NOT_LOADED_YET   IMEMO_FL_USER1
 #define ISEQ_USE_COMPILE_DATA IMEMO_FL_USER2
 #define ISEQ_TRANSLATED       IMEMO_FL_USER3
-#define ISEQ_MARKABLE_ISEQ    IMEMO_FL_USER4
 
 #define ISEQ_EXECUTABLE_P(iseq) (FL_TEST_RAW(((VALUE)iseq), ISEQ_NOT_LOADED_YET | ISEQ_USE_COMPILE_DATA) == 0)
 
@@ -108,12 +114,14 @@ struct iseq_compile_data {
       struct iseq_compile_data_storage *storage_current;
     } insn;
     bool in_rescue;
+    bool in_masgn;
     int loopval_popped;	/* used by NODE_BREAK */
     int last_line;
     int label_no;
     int node_level;
     int isolated_depth;
     unsigned int ci_index;
+    unsigned int ic_index;
     const rb_compile_option_t *option;
     struct rb_id_table *ivar_cache_table;
     const struct rb_builtin_function *builtin_function_table;
@@ -127,10 +135,10 @@ static inline struct iseq_compile_data *
 ISEQ_COMPILE_DATA(const rb_iseq_t *iseq)
 {
     if (iseq->flags & ISEQ_USE_COMPILE_DATA) {
-	return iseq->aux.compile_data;
+        return iseq->aux.compile_data;
     }
     else {
-	return NULL;
+        return NULL;
     }
 }
 
@@ -177,14 +185,10 @@ VALUE rb_iseq_compile_node(rb_iseq_t *iseq, const NODE *node);
 VALUE rb_iseq_compile_callback(rb_iseq_t *iseq, const struct rb_iseq_new_with_callback_callback_func * ifunc);
 VALUE *rb_iseq_original_iseq(const rb_iseq_t *iseq);
 void rb_iseq_build_from_ary(rb_iseq_t *iseq, VALUE misc,
-			    VALUE locals, VALUE args,
-			    VALUE exception, VALUE body);
+                            VALUE locals, VALUE args,
+                            VALUE exception, VALUE body);
 void rb_iseq_mark_insn_storage(struct iseq_compile_data_storage *arena);
 
-/* iseq.c */
-typedef bool rb_iseq_each_i(VALUE *code, VALUE insn, size_t index, void *data);
-void rb_iseq_each(const rb_iseq_t *iseq, size_t start_index, rb_iseq_each_i iterator, void *data);
-
 VALUE rb_iseq_load(VALUE data, VALUE parent, VALUE opt);
 VALUE rb_iseq_parameters(const rb_iseq_t *iseq, int is_proc);
 unsigned int rb_iseq_line_no(const rb_iseq_t *iseq, size_t pos);
@@ -236,28 +240,29 @@ struct iseq_insn_info_entry {
     rb_event_flag_t events;
 };
 
+/*
+ * iseq type:
+ *   CATCH_TYPE_RESCUE, CATCH_TYPE_ENSURE:
+ *     use iseq as continuation.
+ *
+ *   CATCH_TYPE_BREAK (iter):
+ *     use iseq as key.
+ *
+ *   CATCH_TYPE_BREAK (while), CATCH_TYPE_RETRY,
+ *   CATCH_TYPE_REDO, CATCH_TYPE_NEXT:
+ *     NULL.
+ */
+enum rb_catch_type {
+    CATCH_TYPE_RESCUE = INT2FIX(1),
+    CATCH_TYPE_ENSURE = INT2FIX(2),
+    CATCH_TYPE_RETRY  = INT2FIX(3),
+    CATCH_TYPE_BREAK  = INT2FIX(4),
+    CATCH_TYPE_REDO   = INT2FIX(5),
+    CATCH_TYPE_NEXT   = INT2FIX(6)
+};
+
 struct iseq_catch_table_entry {
-    enum catch_type {
-	CATCH_TYPE_RESCUE = INT2FIX(1),
-	CATCH_TYPE_ENSURE = INT2FIX(2),
-	CATCH_TYPE_RETRY  = INT2FIX(3),
-	CATCH_TYPE_BREAK  = INT2FIX(4),
-	CATCH_TYPE_REDO   = INT2FIX(5),
-	CATCH_TYPE_NEXT   = INT2FIX(6)
-    } type;
-
-    /*
-     * iseq type:
-     *   CATCH_TYPE_RESCUE, CATCH_TYPE_ENSURE:
-     *     use iseq as continuation.
-     *
-     *   CATCH_TYPE_BREAK (iter):
-     *     use iseq as key.
-     *
-     *   CATCH_TYPE_BREAK (while), CATCH_TYPE_RETRY,
-     *   CATCH_TYPE_REDO, CATCH_TYPE_NEXT:
-     *     NULL.
-     */
+    enum rb_catch_type type;
     rb_iseq_t *iseq;
 
     unsigned int start;
@@ -275,12 +280,12 @@ static inline int
 iseq_catch_table_bytes(int n)
 {
     enum {
-	catch_table_entry_size = sizeof(struct iseq_catch_table_entry),
-	catch_table_entries_max = (INT_MAX - offsetof(struct iseq_catch_table, entries)) / catch_table_entry_size
+        catch_table_entry_size = sizeof(struct iseq_catch_table_entry),
+        catch_table_entries_max = (INT_MAX - offsetof(struct iseq_catch_table, entries)) / catch_table_entry_size
     };
     if (n > catch_table_entries_max) rb_fatal("too large iseq_catch_table - %d", n);
     return (int)(offsetof(struct iseq_catch_table, entries) +
-		 n * catch_table_entry_size);
+                 n * catch_table_entry_size);
 }
 
 #define INITIAL_ISEQ_COMPILE_DATA_STORAGE_BUFF_SIZE (512)
diff --git a/lex.c.blt b/lex.c.blt
index 92a4793b00..85727ed00f 100644
--- a/lex.c.blt
+++ b/lex.c.blt
@@ -34,7 +34,7 @@
 struct kwtable {short name, id[2], state;};
 const struct kwtable *rb_reserved_word(const char *, unsigned int);
 #ifndef RIPPER
-static const struct kwtable *reserved_word(/*const char *, unsigned int*/);
+static const struct kwtable *reserved_word(register const char *str, register size_t len);
 #define rb_reserved_word(str, len) reserved_word(str, len)
 #line 9 "defs/keywords"
 struct kwtable;
diff --git a/lib/English.gemspec b/lib/English.gemspec
index 274fb047b8..a08542bcda 100644
--- a/lib/English.gemspec
+++ b/lib/English.gemspec
@@ -1,6 +1,6 @@
 Gem::Specification.new do |spec|
   spec.name          = "english"
-  spec.version       = "0.7.1"
+  spec.version       = "0.7.2"
   spec.authors       = ["Yukihiro Matsumoto"]
   spec.email         = ["matz@ruby-lang.org"]
 
diff --git a/lib/abbrev.gemspec b/lib/abbrev.gemspec
index 72837ed2ab..c28b960c8c 100644
--- a/lib/abbrev.gemspec
+++ b/lib/abbrev.gemspec
@@ -1,6 +1,6 @@
 Gem::Specification.new do |spec|
   spec.name          = "abbrev"
-  spec.version       = "0.1.0"
+  spec.version       = "0.1.1"
   spec.authors       = ["Akinori MUSHA"]
   spec.email         = ["knu@idaemons.org"]
 
diff --git a/lib/benchmark/version.rb b/lib/benchmark/version.rb
index 545575f4ab..645966fd80 100644
--- a/lib/benchmark/version.rb
+++ b/lib/benchmark/version.rb
@@ -1,4 +1,4 @@
 # frozen_string_literal: true
 module Benchmark
-  VERSION = "0.2.0"
+  VERSION = "0.2.1"
 end
diff --git a/lib/bundler.rb b/lib/bundler.rb
index 0025dee720..f83268e9cd 100644
--- a/lib/bundler.rb
+++ b/lib/bundler.rb
@@ -19,7 +19,7 @@ require_relative "bundler/build_metadata"
 #
 # Since Ruby 2.6, Bundler is a part of Ruby's standard library.
 #
-# Bunder is used by creating _gemfiles_ listing all the project dependencies
+# Bundler is used by creating _gemfiles_ listing all the project dependencies
 # and (optionally) their versions and then using
 #
 #   require 'bundler/setup'
@@ -41,7 +41,6 @@ module Bundler
 
   autoload :Definition,             File.expand_path("bundler/definition", __dir__)
   autoload :Dependency,             File.expand_path("bundler/dependency", __dir__)
-  autoload :DepProxy,               File.expand_path("bundler/dep_proxy", __dir__)
   autoload :Deprecate,              File.expand_path("bundler/deprecate", __dir__)
   autoload :Digest,                 File.expand_path("bundler/digest", __dir__)
   autoload :Dsl,                    File.expand_path("bundler/dsl", __dir__)
@@ -58,7 +57,7 @@ module Bundler
   autoload :Installer,              File.expand_path("bundler/installer", __dir__)
   autoload :LazySpecification,      File.expand_path("bundler/lazy_specification", __dir__)
   autoload :LockfileParser,         File.expand_path("bundler/lockfile_parser", __dir__)
-  autoload :MatchPlatform,          File.expand_path("bundler/match_platform", __dir__)
+  autoload :MatchRemoteMetadata,    File.expand_path("bundler/match_remote_metadata", __dir__)
   autoload :ProcessLock,            File.expand_path("bundler/process_lock", __dir__)
   autoload :RemoteSpecification,    File.expand_path("bundler/remote_specification", __dir__)
   autoload :Resolver,               File.expand_path("bundler/resolver", __dir__)
@@ -76,11 +75,12 @@ module Bundler
   autoload :StubSpecification,      File.expand_path("bundler/stub_specification", __dir__)
   autoload :UI,                     File.expand_path("bundler/ui", __dir__)
   autoload :URICredentialsFilter,   File.expand_path("bundler/uri_credentials_filter", __dir__)
-  autoload :VersionRanges,          File.expand_path("bundler/version_ranges", __dir__)
+  autoload :URINormalizer,          File.expand_path("bundler/uri_normalizer", __dir__)
+  autoload :SafeMarshal,            File.expand_path("bundler/safe_marshal", __dir__)
 
   class << self
     def configure
-      @configured ||= configure_gem_home_and_path
+      @configure ||= configure_gem_home_and_path
     end
 
     def ui
@@ -97,6 +97,17 @@ module Bundler
       @bundle_path ||= Pathname.new(configured_bundle_path.path).expand_path(root)
     end
 
+    def create_bundle_path
+      SharedHelpers.filesystem_access(bundle_path.to_s) do |p|
+        mkdir_p(p)
+      end unless bundle_path.exist?
+
+      @bundle_path = bundle_path.realpath
+    rescue Errno::EEXIST
+      raise PathError, "Could not install to path `#{bundle_path}` " \
+        "because a file already exists at that path. Either remove or rename the file so the directory can be created."
+    end
+
     def configured_bundle_path
       @configured_bundle_path ||= settings.path.tap(&:validate!)
     end
@@ -199,9 +210,10 @@ module Bundler
     end
 
     def frozen_bundle?
-      frozen = settings[:deployment]
-      frozen ||= settings[:frozen]
-      frozen
+      frozen = settings[:frozen]
+      return frozen unless frozen.nil?
+
+      settings[:deployment]
     end
 
     def locked_gems
@@ -320,9 +332,9 @@ module Bundler
       FileUtils.remove_entry_secure(path) if path && File.exist?(path)
     rescue ArgumentError
       message = <<EOF
-It is a security vulnerability to allow your home directory to be world-writable, and bundler can not continue.
+It is a security vulnerability to allow your home directory to be world-writable, and bundler cannot continue.
 You should probably consider fixing this issue by running `chmod o-w ~` on *nix.
-Please refer to https://ruby-doc.org/stdlib-2.1.2/libdoc/fileutils/rdoc/FileUtils.html#method-c-remove_entry_secure for details.
+Please refer to https://ruby-doc.org/stdlib-3.1.2/libdoc/fileutils/rdoc/FileUtils.html#method-c-remove_entry_secure for details.
 EOF
       File.world_writable?(path) ? Bundler.ui.warn(message) : raise
       raise PathError, "Please fix the world-writable issue with your #{path} directory"
@@ -370,7 +382,7 @@ EOF
 
       if env.key?("RUBYLIB")
         rubylib = env["RUBYLIB"].split(File::PATH_SEPARATOR)
-        rubylib.delete(File.expand_path("..", __FILE__))
+        rubylib.delete(__dir__)
         env["RUBYLIB"] = rubylib.join(File::PATH_SEPARATOR)
       end
 
@@ -444,7 +456,7 @@ EOF
     end
 
     def local_platform
-      return Gem::Platform::RUBY if settings[:force_ruby_platform] || Gem.platforms == [Gem::Platform::RUBY]
+      return Gem::Platform::RUBY if settings[:force_ruby_platform]
       Gem::Platform.local
     end
 
@@ -477,41 +489,9 @@ EOF
       configured_bundle_path.use_system_gems?
     end
 
-    def requires_sudo?
-      return @requires_sudo if defined?(@requires_sudo_ran)
-
-      sudo_present = which "sudo" if settings.allow_sudo?
-
-      if sudo_present
-        # the bundle path and subdirectories need to be writable for RubyGems
-        # to be able to unpack and install gems without exploding
-        path = bundle_path
-        path = path.parent until path.exist?
-
-        # bins are written to a different location on OS X
-        bin_dir = Pathname.new(Bundler.system_bindir)
-        bin_dir = bin_dir.parent until bin_dir.exist?
-
-        # if any directory is not writable, we need sudo
-        files = [path, bin_dir] | Dir[bundle_path.join("build_info/*").to_s] | Dir[bundle_path.join("*").to_s]
-        unwritable_files = files.reject {|f| File.writable?(f) }
-        sudo_needed = !unwritable_files.empty?
-        if sudo_needed
-          Bundler.ui.warn "Following files may not be writable, so sudo is needed:\n  #{unwritable_files.map(&:to_s).sort.join("\n  ")}"
-        end
-      end
-
-      @requires_sudo_ran = true
-      @requires_sudo = settings.allow_sudo? && sudo_present && sudo_needed
-    end
-
     def mkdir_p(path, options = {})
-      if requires_sudo? && !options[:no_sudo]
-        sudo "mkdir -p '#{path}'" unless File.exist?(path)
-      else
-        SharedHelpers.filesystem_access(path, :write) do |p|
-          FileUtils.mkdir_p(p)
-        end
+      SharedHelpers.filesystem_access(path, :write) do |p|
+        FileUtils.mkdir_p(p)
       end
     end
 
@@ -519,7 +499,7 @@ EOF
       if File.file?(executable) && File.executable?(executable)
         executable
       elsif paths = ENV["PATH"]
-        quote = '"'.freeze
+        quote = '"'
         paths.split(File::PATH_SEPARATOR).find do |path|
           path = path[1..-2] if path.start_with?(quote) && path.end_with?(quote)
           executable_path = File.expand_path(executable, path)
@@ -528,41 +508,14 @@ EOF
       end
     end
 
-    def sudo(str)
-      SUDO_MUTEX.synchronize do
-        prompt = "\n\n" + <<-PROMPT.gsub(/^ {6}/, "").strip + " "
-        Your user account isn't allowed to install to the system RubyGems.
-        You can cancel this installation and run:
-
-            bundle config set --local path 'vendor/bundle'
-            bundle install
-
-        to install the gems into ./vendor/bundle/, or you can enter your password
-        and install the bundled gems to RubyGems using sudo.
-
-        Password:
-        PROMPT
-
-        unless @prompted_for_sudo ||= system(%(sudo -k -p "#{prompt}" true))
-          raise SudoNotPermittedError,
-            "Bundler requires sudo access to install at the moment. " \
-            "Try installing again, granting Bundler sudo access when prompted, or installing into a different path."
-        end
-
-        `sudo -p "#{prompt}" #{str}`
-      end
-    end
-
     def read_file(file)
       SharedHelpers.filesystem_access(file, :read) do
         File.open(file, "r:UTF-8", &:read)
       end
     end
 
-    def load_marshal(data)
-      Marshal.load(data)
-    rescue TypeError => e
-      raise MarshalError, "#{e.class}: #{e.message}"
+    def safe_load_marshal(data)
+      load_marshal(data, :marshal_proc => SafeMarshal.proc)
     end
 
     def load_gemspec(file, validate = false)
@@ -571,7 +524,7 @@ EOF
       @gemspec_cache[key] ||= load_gemspec_uncached(file, validate)
       # Protect against caching side-effected gemspecs by returning a
       # new instance each time.
-      @gemspec_cache[key].dup if @gemspec_cache[key]
+      @gemspec_cache[key]&.dup
     end
 
     def load_gemspec_uncached(file, validate = false)
@@ -598,7 +551,7 @@ EOF
 
     def git_present?
       return @git_present if defined?(@git_present)
-      @git_present = Bundler.which("git") || Bundler.which("git.exe")
+      @git_present = Bundler.which("git#{RbConfig::CONFIG["EXEEXT"]}")
     end
 
     def feature_flag
@@ -620,7 +573,7 @@ EOF
       @bin_path = nil
       @bundler_major_version = nil
       @bundle_path = nil
-      @configured = nil
+      @configure = nil
       @configured_bundle_path = nil
       @definition = nil
       @load = nil
@@ -653,6 +606,12 @@ EOF
 
     private
 
+    def load_marshal(data, marshal_proc: nil)
+      Marshal.load(data, marshal_proc)
+    rescue TypeError => e
+      raise MarshalError, "#{e.class}: #{e.message}"
+    end
+
     def eval_yaml_gemspec(path, contents)
       Kernel.require "psych"
 
diff --git a/lib/bundler/build_metadata.rb b/lib/bundler/build_metadata.rb
index 0846e82e06..8bffb2fae7 100644
--- a/lib/bundler/build_metadata.rb
+++ b/lib/bundler/build_metadata.rb
@@ -27,7 +27,7 @@ module Bundler
 
       # If Bundler has been installed without its .git directory and without a
       # commit instance variable then we can't determine its commits SHA.
-      git_dir = File.join(File.expand_path("../../../..", __FILE__), ".git")
+      git_dir = File.expand_path("../../../.git", __dir__)
       if File.directory?(git_dir)
         return @git_commit_sha = Dir.chdir(git_dir) { `git rev-parse --short HEAD`.strip.freeze }
       end
diff --git a/lib/bundler/bundler.gemspec b/lib/bundler/bundler.gemspec
index 38c533b0c1..da50b46225 100644
--- a/lib/bundler/bundler.gemspec
+++ b/lib/bundler/bundler.gemspec
@@ -22,17 +22,15 @@ Gem::Specification.new do |s|
   s.summary     = "The best way to manage your application's dependencies"
   s.description = "Bundler manages an application's dependencies through its entire life, across many machines, systematically and repeatably"
 
-  if s.respond_to?(:metadata=)
-    s.metadata = {
-      "bug_tracker_uri" => "https://github.com/rubygems/rubygems/issues?q=is%3Aopen+is%3Aissue+label%3ABundler",
-      "changelog_uri" => "https://github.com/rubygems/rubygems/blob/master/bundler/CHANGELOG.md",
-      "homepage_uri" => "https://bundler.io/",
-      "source_code_uri" => "https://github.com/rubygems/rubygems/",
-    }
-  end
+  s.metadata = {
+    "bug_tracker_uri" => "https://github.com/rubygems/rubygems/issues?q=is%3Aopen+is%3Aissue+label%3ABundler",
+    "changelog_uri" => "https://github.com/rubygems/rubygems/blob/master/bundler/CHANGELOG.md",
+    "homepage_uri" => "https://bundler.io/",
+    "source_code_uri" => "https://github.com/rubygems/rubygems/tree/master/bundler",
+  }
 
-  s.required_ruby_version     = ">= 2.3.0"
-  s.required_rubygems_version = ">= 2.5.2"
+  s.required_ruby_version     = ">= 2.6.0"
+  s.required_rubygems_version = ">= 3.0.1"
 
   s.files = Dir.glob("lib/bundler{.rb,/**/*}", File::FNM_DOTMATCH).reject {|f| File.directory?(f) }
 
diff --git a/lib/bundler/cli.rb b/lib/bundler/cli.rb
index 922ba469a4..a3eb494db2 100644
--- a/lib/bundler/cli.rb
+++ b/lib/bundler/cli.rb
@@ -10,6 +10,7 @@ module Bundler
 
     AUTO_INSTALL_CMDS = %w[show binstubs outdated exec open console licenses clean].freeze
     PARSEABLE_COMMANDS = %w[check config help exec platform show version].freeze
+    EXTENSIONS = ["c", "rust"].freeze
 
     COMMAND_ALIASES = {
       "check" => "c",
@@ -22,6 +23,8 @@ module Bundler
     }.freeze
 
     def self.start(*)
+      check_deprecated_ext_option(ARGV) if ARGV.include?("--ext")
+
       super
     ensure
       Bundler::SharedHelpers.print_major_deprecations!
@@ -153,6 +156,7 @@ module Bundler
       dependency listed in the gemspec file to the newly created Gemfile.
     D
     method_option "gemspec", :type => :string, :banner => "Use the specified .gemspec to create the Gemfile"
+    method_option "gemfile", :type => :string, :banner => "Use the specified name for the gemfile instead of 'Gemfile'"
     def init
       require_relative "cli/init"
       Init.new(options.dup).run
@@ -218,6 +222,8 @@ module Bundler
       "Specify the number of jobs to run in parallel"
     method_option "local", :type => :boolean, :banner =>
       "Do not attempt to fetch gems remotely and use the gem cache instead"
+    method_option "prefer-local", :type => :boolean, :banner =>
+      "Only attempt to fetch gems remotely if not present locally, even if newer versions are available remotely"
     method_option "no-cache", :type => :boolean, :banner =>
       "Don't update the existing gem cache."
     method_option "redownload", :type => :boolean, :aliases => "--force", :banner =>
@@ -236,7 +242,7 @@ module Bundler
       "Install to the system location ($BUNDLE_PATH or $GEM_HOME) even if the bundle was previously installed somewhere else for this application"
     method_option "trust-policy", :alias => "P", :type => :string, :banner =>
       "Gem trust policy (like gem install -P). Must be one of " +
-        Bundler.rubygems.security_policy_keys.join("|")
+      Bundler.rubygems.security_policy_keys.join("|")
     method_option "without", :type => :array, :banner =>
       "Exclude gems that are part of the specified named group."
     method_option "with", :type => :array, :banner =>
@@ -290,6 +296,8 @@ module Bundler
       "Prefer updating only to next minor version"
     method_option "major", :type => :boolean, :banner =>
       "Prefer updating to next major version (default)"
+    method_option "pre", :type => :boolean, :banner =>
+      "Always choose the highest allowed version when updating gems, regardless of prerelease status"
     method_option "strict", :type => :boolean, :banner =>
       "Do not allow any gem to be updated past latest --patch | --minor | --major"
     method_option "conservative", :type => :boolean, :banner =>
@@ -370,6 +378,7 @@ module Bundler
     method_option "group", :aliases => "-g", :type => :string
     method_option "source", :aliases => "-s", :type => :string
     method_option "require", :aliases => "-r", :type => :string, :banner => "Adds require path to gem. Provide false, or a path as a string."
+    method_option "path", :type => :string
     method_option "git", :type => :string
     method_option "github", :type => :string
     method_option "branch", :type => :string
@@ -399,9 +408,9 @@ module Bundler
       "Do not attempt to fetch gems remotely and use the gem cache instead"
     method_option "pre", :type => :boolean, :banner => "Check for newer pre-release gems"
     method_option "source", :type => :array, :banner => "Check against a specific source"
-    method_option "filter-strict", :type => :boolean, :banner =>
+    method_option "filter-strict", :type => :boolean, :aliases => "--strict", :banner =>
       "Only list newer versions allowed by your Gemfile requirements"
-    method_option "strict", :type => :boolean, :aliases => "--update-strict", :banner =>
+    method_option "update-strict", :type => :boolean, :banner =>
       "Strict conservative resolution, do not allow any gem to be updated past latest --patch | --minor | --major"
     method_option "minor", :type => :boolean, :banner => "Prefer updating only to next minor version"
     method_option "major", :type => :boolean, :banner => "Prefer updating to next major version (default)"
@@ -501,6 +510,7 @@ module Bundler
     subcommand "config", Config
 
     desc "open GEM", "Opens the source directory of the given bundled gem"
+    method_option "path", :type => :string, :lazy_default => "", :banner => "Open relative path of the gem source."
     def open(name)
       require_relative "cli/open"
       Open.new(options, name).run
@@ -514,7 +524,7 @@ module Bundler
       end
     end
 
-    desc "version", "Prints the bundler's version information"
+    desc "version", "Prints Bundler version information"
     def version
       cli_help = current_command.name == "cli_help"
       if cli_help || ARGV.include?("version")
@@ -571,7 +581,7 @@ module Bundler
     method_option :edit, :type => :string, :aliases => "-e", :required => false, :banner => "EDITOR",
                          :lazy_default => [ENV["BUNDLER_EDITOR"], ENV["VISUAL"], ENV["EDITOR"]].find {|e| !e.nil? && !e.empty? },
                          :desc => "Open generated gemspec in the specified editor (defaults to $EDITOR or $BUNDLER_EDITOR)"
-    method_option :ext, :type => :boolean, :default => false, :desc => "Generate the boilerplate for C extension code"
+    method_option :ext, :type => :string, :desc => "Generate the boilerplate for C extension code.", :enum => EXTENSIONS
     method_option :git, :type => :boolean, :default => true, :desc => "Initialize a git repo inside your library."
     method_option :mit, :type => :boolean, :desc => "Generate an MIT license file. Set a default with `bundle config set --global gem.mit true`."
     method_option :rubocop, :type => :boolean, :desc => "Add rubocop to the generated Rakefile and gemspec. Set a default with `bundle config set --global gem.rubocop true`."
@@ -579,7 +589,7 @@ module Bundler
     method_option :test, :type => :string, :lazy_default => Bundler.settings["gem.test"] || "", :aliases => "-t", :banner => "Use the specified test framework for your library",
                          :desc => "Generate a test directory for your library, either rspec, minitest or test-unit. Set a default with `bundle config set --global gem.test (rspec|minitest|test-unit)`."
     method_option :ci, :type => :string, :lazy_default => Bundler.settings["gem.ci"] || "",
-                       :desc => "Generate CI configuration, either GitHub Actions, Travis CI, GitLab CI or CircleCI. Set a default with `bundle config set --global gem.ci (github|travis|gitlab|circle)`"
+                       :desc => "Generate CI configuration, either GitHub Actions, GitLab CI or CircleCI. Set a default with `bundle config set --global gem.ci (github|gitlab|circle)`"
     method_option :linter, :type => :string, :lazy_default => Bundler.settings["gem.linter"] || "",
                            :desc => "Add a linter and code formatter, either RuboCop or Standard. Set a default with `bundle config set --global gem.linter (rubocop|standard)`"
     method_option :github_username, :type => :string, :default => Bundler.settings["gem.github_username"], :banner => "Set your username on GitHub", :desc => "Fill in GitHub username on README so that you don't have to do it manually. Set a default with `bundle config set --global gem.github_username <your_username>`."
@@ -610,14 +620,14 @@ module Bundler
     private :gem
 
     def self.source_root
-      File.expand_path(File.join(File.dirname(__FILE__), "templates"))
+      File.expand_path("templates", __dir__)
     end
 
     desc "clean [OPTIONS]", "Cleans up unused gems in your bundler directory", :hide => true
     method_option "dry-run", :type => :boolean, :default => false, :banner =>
       "Only print out changes, do not clean gems"
     method_option "force", :type => :boolean, :default => false, :banner =>
-      "Forces clean even if --path is not set"
+      "Forces cleaning up unused gems even if Bundler is configured to use globally installed gems. As a consequence, removes all system gems except for the ones in the current application."
     def clean
       require_relative "cli/clean"
       Clean.new(options.dup).run
@@ -665,10 +675,14 @@ module Bundler
       "If updating, prefer updating only to next minor version"
     method_option "major", :type => :boolean, :banner =>
       "If updating, prefer updating to next major version (default)"
+    method_option "pre", :type => :boolean, :banner =>
+      "If updating, always choose the highest allowed version, regardless of prerelease status"
     method_option "strict", :type => :boolean, :banner =>
       "If updating, do not allow any gem to be updated past latest --patch | --minor | --major"
     method_option "conservative", :type => :boolean, :banner =>
       "If updating, use bundle install conservative update behavior and do not allow shared dependencies to be updated"
+    method_option "bundler", :type => :string, :lazy_default => "> 0.a", :banner =>
+      "Update the locked version of bundler"
     def lock
       require_relative "cli/lock"
       Lock.new(options).run
@@ -746,6 +760,38 @@ module Bundler
       end
     end
 
+    def self.check_deprecated_ext_option(arguments)
+      # when deprecated version of `--ext` is called
+      # print out deprecation warning and pretend `--ext=c` was provided
+      if deprecated_ext_value?(arguments)
+        SharedHelpers.major_deprecation 2, "Extensions can now be generated using C or Rust, so `--ext` with no arguments has been deprecated. Please select a language, e.g. `--ext=rust` to generate a Rust extension. This gem will now be generated as if `--ext=c` was used."
+        arguments[arguments.index("--ext")] = "--ext=c"
+      end
+    end
+
+    def self.deprecated_ext_value?(arguments)
+      index = arguments.index("--ext")
+      next_argument = arguments[index+1]
+
+      # it is ok when --ext is followed with valid extension value
+      # for example `bundle gem hello --ext c`
+      return false if EXTENSIONS.include?(next_argument)
+
+      # deprecated call when --ext is called with no value in last position
+      # for example `bundle gem hello_gem --ext`
+      return true if next_argument.nil?
+
+      # deprecated call when --ext is followed by other parameter
+      # for example `bundle gem --ext --no-ci hello_gem`
+      return true if next_argument.start_with?("-")
+
+      # deprecated call when --ext is followed by gem name
+      # for example `bundle gem --ext hello_gem`
+      return true if next_argument
+
+      false
+    end
+
     private
 
     # Automatically invoke `bundle install` and resume if
diff --git a/lib/bundler/cli/add.rb b/lib/bundler/cli/add.rb
index 5bcf30d82d..08fa6547fb 100644
--- a/lib/bundler/cli/add.rb
+++ b/lib/bundler/cli/add.rb
@@ -40,7 +40,7 @@ module Bundler
       raise InvalidOption, "Please specify gems to add." if gems.empty?
 
       version.to_a.each do |v|
-        raise InvalidOption, "Invalid gem requirement pattern '#{v}'" unless Gem::Requirement::PATTERN =~ v.to_s
+        raise InvalidOption, "Invalid gem requirement pattern '#{v}'" unless Gem::Requirement::PATTERN.match?(v.to_s)
       end
     end
   end
diff --git a/lib/bundler/cli/binstubs.rb b/lib/bundler/cli/binstubs.rb
index 639c01ff39..fc2fad47a5 100644
--- a/lib/bundler/cli/binstubs.rb
+++ b/lib/bundler/cli/binstubs.rb
@@ -11,7 +11,7 @@ module Bundler
     def run
       Bundler.definition.validate_runtime!
       path_option = options["path"]
-      path_option = nil if path_option && path_option.empty?
+      path_option = nil if path_option&.empty?
       Bundler.settings.set_command_option :bin, path_option if options["path"]
       Bundler.settings.set_command_option_if_given :shebang, options["shebang"]
       installer = Installer.new(Bundler.root, Bundler.definition)
@@ -40,7 +40,11 @@ module Bundler
         end
 
         if options[:standalone]
-          next Bundler.ui.warn("Sorry, Bundler can only be run via RubyGems.") if gem_name == "bundler"
+          if gem_name == "bundler"
+            Bundler.ui.warn("Sorry, Bundler can only be run via RubyGems.") unless options[:all]
+            next
+          end
+
           Bundler.settings.temporary(:path => (Bundler.settings[:path] || Bundler.root)) do
             installer.generate_standalone_bundler_executable_stubs(spec, installer_opts)
           end
diff --git a/lib/bundler/cli/check.rb b/lib/bundler/cli/check.rb
index 65c51337d2..cc1f37f0c3 100644
--- a/lib/bundler/cli/check.rb
+++ b/lib/bundler/cli/check.rb
@@ -17,7 +17,7 @@ module Bundler
       begin
         definition.resolve_only_locally!
         not_installed = definition.missing_specs
-      rescue GemNotFound, VersionConflict
+      rescue GemNotFound, SolveFailure
         Bundler.ui.error "Bundler can't satisfy your Gemfile's dependencies."
         Bundler.ui.warn "Install missing gems with `bundle install`."
         exit 1
diff --git a/lib/bundler/cli/common.rb b/lib/bundler/cli/common.rb
index 1a469f1d34..d654406f65 100644
--- a/lib/bundler/cli/common.rb
+++ b/lib/bundler/cli/common.rb
@@ -15,6 +15,7 @@ module Bundler
     end
 
     def self.output_fund_metadata_summary
+      return if Bundler.settings["ignore_funding_requests"]
       definition = Bundler.definition
       current_dependencies = definition.requested_dependencies
       current_specs = definition.specs
@@ -40,7 +41,7 @@ module Bundler
     end
 
     def self.verbalize_groups(groups)
-      groups.map!{|g| "'#{g}'" }
+      groups.map! {|g| "'#{g}'" }
       group_list = [groups[0...-1].join(", "), groups[-1..-1]].
         reject {|s| s.to_s.empty? }.join(" and ")
       group_str = groups.size == 1 ? "group" : "groups"
@@ -110,6 +111,7 @@ module Bundler
       definition.gem_version_promoter.tap do |gvp|
         gvp.level = patch_level.first || :major
         gvp.strict = options[:strict] || options["filter-strict"]
+        gvp.pre = options[:pre]
       end
     end
 
diff --git a/lib/bundler/cli/console.rb b/lib/bundler/cli/console.rb
index 97b8dc0663..1eb8ea8254 100644
--- a/lib/bundler/cli/console.rb
+++ b/lib/bundler/cli/console.rb
@@ -30,9 +30,9 @@ module Bundler
 
     def get_constant(name)
       const_name = {
-        "pry"  => :Pry,
+        "pry" => :Pry,
         "ripl" => :Ripl,
-        "irb"  => :IRB,
+        "irb" => :IRB,
       }[name]
       Object.const_get(const_name)
     rescue NameError
diff --git a/lib/bundler/cli/doctor.rb b/lib/bundler/cli/doctor.rb
index 74444ad0ce..e299a5a8c2 100644
--- a/lib/bundler/cli/doctor.rb
+++ b/lib/bundler/cli/doctor.rb
@@ -73,12 +73,10 @@ module Bundler
       definition.specs.each do |spec|
         bundles_for_gem(spec).each do |bundle|
           bad_paths = dylibs(bundle).select do |f|
-            begin
-              Fiddle.dlopen(f)
-              false
-            rescue Fiddle::DLError
-              true
-            end
+            Fiddle.dlopen(f)
+            false
+          rescue Fiddle::DLError
+            true
           end
           if bad_paths.any?
             broken_links[spec] ||= []
diff --git a/lib/bundler/cli/gem.rb b/lib/bundler/cli/gem.rb
index c4c76d1b69..7f1200f4a0 100644
--- a/lib/bundler/cli/gem.rb
+++ b/lib/bundler/cli/gem.rb
@@ -15,7 +15,7 @@ module Bundler
       "test-unit" => "3.0",
     }.freeze
 
-    attr_reader :options, :gem_name, :thor, :name, :target
+    attr_reader :options, :gem_name, :thor, :name, :target, :extension
 
     def initialize(options, gem_name, thor)
       @options = options
@@ -28,7 +28,11 @@ module Bundler
       @name = @gem_name
       @target = SharedHelpers.pwd.join(gem_name)
 
-      validate_ext_name if options[:ext]
+      @extension = options[:ext]
+
+      validate_ext_name if @extension
+      validate_rust_builder_rubygems_version if @extension == "rust"
+      travis_removal_info
     end
 
     def run
@@ -55,21 +59,22 @@ module Bundler
       end
 
       config = {
-        :name             => name,
+        :name => name,
         :underscored_name => underscored_name,
-        :namespaced_path  => namespaced_path,
-        :makefile_path    => "#{underscored_name}/#{underscored_name}",
-        :constant_name    => constant_name,
-        :constant_array   => constant_array,
-        :author           => git_author_name.empty? ? "TODO: Write your name" : git_author_name,
-        :email            => git_user_email.empty? ? "TODO: Write your email address" : git_user_email,
-        :test             => options[:test],
-        :ext              => options[:ext],
-        :exe              => options[:exe],
-        :bundler_version  => bundler_dependency_version,
-        :git              => use_git,
-        :github_username  => github_username.empty? ? "[USERNAME]" : github_username,
+        :namespaced_path => namespaced_path,
+        :makefile_path => "#{underscored_name}/#{underscored_name}",
+        :constant_name => constant_name,
+        :constant_array => constant_array,
+        :author => git_author_name.empty? ? "TODO: Write your name" : git_author_name,
+        :email => git_user_email.empty? ? "TODO: Write your email address" : git_user_email,
+        :test => options[:test],
+        :ext => extension,
+        :exe => options[:exe],
+        :bundler_version => bundler_dependency_version,
+        :git => use_git,
+        :github_username => github_username.empty? ? "[USERNAME]" : github_username,
         :required_ruby_version => required_ruby_version,
+        :rust_builder_required_rubygems_version => rust_builder_required_rubygems_version,
         :minitest_constant_name => minitest_constant_name,
       }
       ensure_safe_gem_name(name, constant_array)
@@ -132,8 +137,6 @@ module Bundler
       case config[:ci]
       when "github"
         templates.merge!("github/workflows/main.yml.tt" => ".github/workflows/main.yml")
-      when "travis"
-        templates.merge!("travis.yml.tt" => ".travis.yml")
       when "gitlab"
         templates.merge!("gitlab-ci.yml.tt" => ".gitlab-ci.yml")
       when "circle"
@@ -188,14 +191,23 @@ module Bundler
 
       templates.merge!("exe/newgem.tt" => "exe/#{name}") if config[:exe]
 
-      if options[:ext]
+      if extension == "c"
         templates.merge!(
-          "ext/newgem/extconf.rb.tt" => "ext/#{name}/extconf.rb",
+          "ext/newgem/extconf-c.rb.tt" => "ext/#{name}/extconf.rb",
           "ext/newgem/newgem.h.tt" => "ext/#{name}/#{underscored_name}.h",
           "ext/newgem/newgem.c.tt" => "ext/#{name}/#{underscored_name}.c"
         )
       end
 
+      if extension == "rust"
+        templates.merge!(
+          "Cargo.toml.tt" => "Cargo.toml",
+          "ext/newgem/Cargo.toml.tt" => "ext/#{name}/Cargo.toml",
+          "ext/newgem/extconf-rust.rb.tt" => "ext/#{name}/extconf.rb",
+          "ext/newgem/src/lib.rs.tt" => "ext/#{name}/src/lib.rs",
+        )
+      end
+
       if target.exist? && !target.directory?
         Bundler.ui.error "Couldn't create a new gem named `#{gem_name}` because there's an existing file named `#{gem_name}`."
         exit Bundler::BundlerError.all_errors[Bundler::GenericSystemCallError]
@@ -270,7 +282,7 @@ module Bundler
         Bundler.ui.info hint_text("test")
 
         result = Bundler.ui.ask "Enter a test framework. rspec/minitest/test-unit/(none):"
-        if result =~ /rspec|minitest|test-unit/
+        if /rspec|minitest|test-unit/.match?(result)
           test_framework = result
         else
           test_framework = false
@@ -306,12 +318,11 @@ module Bundler
           "* CircleCI:       https://circleci.com/\n" \
           "* GitHub Actions: https://github.com/features/actions\n" \
           "* GitLab CI:      https://docs.gitlab.com/ee/ci/\n" \
-          "* Travis CI:      https://travis-ci.org/\n" \
           "\n"
         Bundler.ui.info hint_text("ci")
 
-        result = Bundler.ui.ask "Enter a CI service. github/travis/gitlab/circle/(none):"
-        if result =~ /github|travis|gitlab|circle/
+        result = Bundler.ui.ask "Enter a CI service. github/gitlab/circle/(none):"
+        if /github|gitlab|circle/.match?(result)
           ci_template = result
         else
           ci_template = false
@@ -342,7 +353,7 @@ module Bundler
         Bundler.ui.info hint_text("linter")
 
         result = Bundler.ui.ask "Enter a linter. rubocop/standard/(none):"
-        if result =~ /rubocop|standard/
+        if /rubocop|standard/.match?(result)
           linter_template = result
         else
           linter_template = false
@@ -389,7 +400,7 @@ module Bundler
     end
 
     def ensure_safe_gem_name(name, constant_array)
-      if name =~ /^\d/
+      if /^\d/.match?(name)
         Bundler.ui.error "Invalid gem name #{name} Please give a name which does not start with numbers."
         exit 1
       end
@@ -415,28 +426,39 @@ module Bundler
       thor.run(%(#{editor} "#{file}"))
     end
 
+    def rust_builder_required_rubygems_version
+      "3.3.11"
+    end
+
     def required_ruby_version
-      if Gem.ruby_version < Gem::Version.new("2.4.a") then "2.3.0"
-      elsif Gem.ruby_version < Gem::Version.new("2.5.a") then "2.4.0"
-      elsif Gem.ruby_version < Gem::Version.new("2.6.a") then "2.5.0"
-      else
-        "2.6.0"
-      end
+      "2.6.0"
     end
 
     def rubocop_version
-      if Gem.ruby_version < Gem::Version.new("2.4.a") then "0.81.0"
-      elsif Gem.ruby_version < Gem::Version.new("2.5.a") then "1.12"
-      else
-        "1.21"
-      end
+      "1.21"
     end
 
     def standard_version
-      if Gem.ruby_version < Gem::Version.new("2.4.a") then "0.2.5"
-      elsif Gem.ruby_version < Gem::Version.new("2.5.a") then "1.0"
-      else
-        "1.3"
+      "1.3"
+    end
+
+    # TODO: remove at next minor release
+    def travis_removal_info
+      if options[:ci] == "travis"
+        Bundler.ui.error "Support for Travis CI was removed from gem skeleton generator."
+        exit 1
+      end
+
+      if Bundler.settings["gem.ci"] == "travis"
+        Bundler.ui.error "Support for Travis CI was removed from gem skeleton generator, but it is present in bundle config. Please configure another provider using `bundle config set gem.ci SERVICE` (where SERVICE is one of github/gitlab/circle) or unset configuration using `bundle config unset gem.ci`."
+        exit 1
+      end
+    end
+
+    def validate_rust_builder_rubygems_version
+      if Gem::Version.new(rust_builder_required_rubygems_version) > Gem.rubygems_version
+        Bundler.ui.error "Your RubyGems version (#{Gem.rubygems_version}) is too old to build Rust extension. Please update your RubyGems using `gem update --system` or any other way and try again."
+        exit 1
       end
     end
   end
diff --git a/lib/bundler/cli/info.rb b/lib/bundler/cli/info.rb
index 38bc008cb5..36c7a58f12 100644
--- a/lib/bundler/cli/info.rb
+++ b/lib/bundler/cli/info.rb
@@ -33,7 +33,7 @@ module Bundler
     def default_gem_spec(gem_name)
       return unless Gem::Specification.respond_to?(:find_all_by_name)
       gem_spec = Gem::Specification.find_all_by_name(gem_name).last
-      return gem_spec if gem_spec && gem_spec.respond_to?(:default_gem?) && gem_spec.default_gem?
+      return gem_spec if gem_spec&.default_gem?
     end
 
     def spec_not_found(gem_name)
@@ -47,7 +47,7 @@ module Bundler
     def print_gem_path(spec)
       name = spec.name
       if name == "bundler"
-        path = File.expand_path("../../../..", __FILE__)
+        path = File.expand_path("../../..", __dir__)
       else
         path = spec.full_gem_path
         if spec.deleted_gem?
diff --git a/lib/bundler/cli/init.rb b/lib/bundler/cli/init.rb
index d851d02d42..246b9d6460 100644
--- a/lib/bundler/cli/init.rb
+++ b/lib/bundler/cli/init.rb
@@ -32,7 +32,11 @@ module Bundler
           file << spec.to_gemfile
         end
       else
-        FileUtils.cp(File.expand_path("../../templates/#{gemfile}", __FILE__), gemfile)
+        File.open(File.expand_path("../templates/Gemfile", __dir__), "r") do |template|
+          File.open(gemfile, "wb") do |destination|
+            IO.copy_stream(template, destination)
+          end
+        end
       end
 
       puts "Writing new #{gemfile} to #{SharedHelpers.pwd}/#{gemfile}"
@@ -41,7 +45,7 @@ module Bundler
     private
 
     def gemfile
-      @gemfile ||= Bundler.preferred_gemfile_name
+      @gemfile ||= options[:gemfile] || Bundler.preferred_gemfile_name
     end
   end
 end
diff --git a/lib/bundler/cli/install.rb b/lib/bundler/cli/install.rb
index e9b85f7f6f..c71bcf159f 100644
--- a/lib/bundler/cli/install.rb
+++ b/lib/bundler/cli/install.rb
@@ -94,9 +94,8 @@ module Bundler
 
     def warn_if_root
       return if Bundler.settings[:silence_root_warning] || Gem.win_platform? || !Process.uid.zero?
-      Bundler.ui.warn "Don't run Bundler as root. Bundler can ask for sudo " \
-        "if it is needed, and installing your bundle as root will break this " \
-        "application for all non-root users on this machine.", :wrap => true
+      Bundler.ui.warn "Don't run Bundler as root. Installing your bundle as root " \
+                      "will break this application for all non-root users on this machine.", :wrap => true
     end
 
     def dependencies_count_for(definition)
@@ -147,12 +146,15 @@ module Bundler
     def normalize_settings
       Bundler.settings.set_command_option :path, nil if options[:system]
       Bundler.settings.set_command_option_if_given :path, options[:path]
-      Bundler.settings.temporary(:path_relative_to_cwd => false) do
-        Bundler.settings.set_command_option :path, "bundle" if options["standalone"] && Bundler.settings[:path].nil?
+
+      if options["standalone"] && Bundler.settings[:path].nil? && !options["local"]
+        Bundler.settings.temporary(:path_relative_to_cwd => false) do
+          Bundler.settings.set_command_option :path, "bundle"
+        end
       end
 
       bin_option = options["binstubs"]
-      bin_option = nil if bin_option && bin_option.empty?
+      bin_option = nil if bin_option&.empty?
       Bundler.settings.set_command_option :bin, bin_option if options["binstubs"]
 
       Bundler.settings.set_command_option_if_given :shebang, options["shebang"]
diff --git a/lib/bundler/cli/lock.rb b/lib/bundler/cli/lock.rb
index 7d613a6644..cb3ed27138 100644
--- a/lib/bundler/cli/lock.rb
+++ b/lib/bundler/cli/lock.rb
@@ -15,19 +15,22 @@ module Bundler
       end
 
       print = options[:print]
-      ui = Bundler.ui
-      Bundler.ui = UI::Silent.new if print
+      previous_ui_level = Bundler.ui.level
+      Bundler.ui.level = "silent" if print
 
       Bundler::Fetcher.disable_endpoint = options["full-index"]
 
       update = options[:update]
       conservative = options[:conservative]
+      bundler = options[:bundler]
 
       if update.is_a?(Array) # unlocking specific gems
         Bundler::CLI::Common.ensure_all_gems_in_lockfile!(update)
         update = { :gems => update, :conservative => conservative }
-      elsif update
-        update = { :conservative => conservative } if conservative
+      elsif update && conservative
+        update = { :conservative => conservative }
+      elsif update && bundler
+        update = { :bundler => bundler }
       end
       definition = Bundler.definition(update)
 
@@ -61,7 +64,7 @@ module Bundler
         definition.lock(file)
       end
 
-      Bundler.ui = ui
+      Bundler.ui.level = previous_ui_level
     end
   end
 end
diff --git a/lib/bundler/cli/open.rb b/lib/bundler/cli/open.rb
index ea504344f3..8522ec92d6 100644
--- a/lib/bundler/cli/open.rb
+++ b/lib/bundler/cli/open.rb
@@ -2,23 +2,25 @@
 
 module Bundler
   class CLI::Open
-    attr_reader :options, :name
+    attr_reader :options, :name, :path
     def initialize(options, name)
       @options = options
       @name = name
+      @path = options[:path] unless options[:path].nil?
     end
 
     def run
+      raise InvalidOption, "Cannot specify `--path` option without a value" if !@path.nil? && @path.empty?
       editor = [ENV["BUNDLER_EDITOR"], ENV["VISUAL"], ENV["EDITOR"]].find {|e| !e.nil? && !e.empty? }
       return Bundler.ui.info("To open a bundled gem, set $EDITOR or $BUNDLER_EDITOR") unless editor
       return unless spec = Bundler::CLI::Common.select_spec(name, :regex_match)
       if spec.default_gem?
         Bundler.ui.info "Unable to open #{name} because it's a default gem, so the directory it would normally be installed to does not exist."
       else
-        path = spec.full_gem_path
-        Dir.chdir(path) do
+        root_path = spec.full_gem_path
+        Dir.chdir(root_path) do
           require "shellwords"
-          command = Shellwords.split(editor) + [path]
+          command = Shellwords.split(editor) << File.join([root_path, path].compact)
           Bundler.with_original_env do
             system(*command)
           end || Bundler.ui.info("Could not run '#{command.join(" ")}'")
diff --git a/lib/bundler/cli/outdated.rb b/lib/bundler/cli/outdated.rb
index d5183b060b..68c701aefb 100644
--- a/lib/bundler/cli/outdated.rb
+++ b/lib/bundler/cli/outdated.rb
@@ -46,7 +46,7 @@ module Bundler
 
       Bundler::CLI::Common.configure_gem_version_promoter(
         Bundler.definition,
-        options
+        options.merge(:strict => @strict)
       )
 
       definition_resolution = proc do
@@ -111,9 +111,7 @@ module Bundler
           end.compact
 
           if options[:parseable]
-            relevant_outdated_gems.each do |gems|
-              print_gems(gems)
-            end
+            print_gems(relevant_outdated_gems)
           else
             print_gems_table(relevant_outdated_gems)
           end
@@ -129,6 +127,12 @@ module Bundler
 
     private
 
+    def loaded_from_for(spec)
+      return unless spec.respond_to?(:loaded_from)
+
+      spec.loaded_from
+    end
+
     def groups_text(group_text, groups)
       "#{group_text}#{groups.split(",").size > 1 ? "s" : ""} \"#{groups}\""
     end
@@ -184,10 +188,13 @@ module Bundler
 
     def print_gem(current_spec, active_spec, dependency, groups)
       spec_version = "#{active_spec.version}#{active_spec.git_version}"
-      spec_version += " (from #{active_spec.loaded_from})" if Bundler.ui.debug? && active_spec.loaded_from
+      if Bundler.ui.debug?
+        loaded_from = loaded_from_for(active_spec)
+        spec_version += " (from #{loaded_from})" if loaded_from
+      end
       current_version = "#{current_spec.version}#{current_spec.git_version}"
 
-      if dependency && dependency.specific?
+      if dependency&.specific?
         dependency_version = %(, requested #{dependency.requirement})
       end
 
@@ -211,7 +218,7 @@ module Bundler
       dependency = dependency.requirement if dependency
 
       ret_val = [active_spec.name, current_version, spec_version, dependency.to_s, groups.to_s]
-      ret_val << active_spec.loaded_from.to_s if Bundler.ui.debug?
+      ret_val << loaded_from_for(active_spec).to_s if Bundler.ui.debug?
       ret_val
     end
 
diff --git a/lib/bundler/cli/platform.rb b/lib/bundler/cli/platform.rb
index 068c765aad..32d68abbb1 100644
--- a/lib/bundler/cli/platform.rb
+++ b/lib/bundler/cli/platform.rb
@@ -8,12 +8,12 @@ module Bundler
     end
 
     def run
-      platforms, ruby_version = Bundler.ui.silence do
-        locked_ruby_version = Bundler.locked_gems && Bundler.locked_gems.ruby_version
-        gemfile_ruby_version = Bundler.definition.ruby_version && Bundler.definition.ruby_version.single_version_string
-        [Bundler.definition.platforms.map {|p| "* #{p}" },
-         locked_ruby_version || gemfile_ruby_version]
+      ruby_version = if Bundler.locked_gems
+        Bundler.locked_gems.ruby_version&.gsub(/p\d+\Z/, "")
+      else
+        Bundler.definition.ruby_version&.single_version_string
       end
+
       output = []
 
       if options[:ruby]
@@ -23,6 +23,8 @@ module Bundler
           output << "No ruby version specified"
         end
       else
+        platforms = Bundler.definition.platforms.map {|p| "* #{p}" }
+
         output << "Your platform is: #{Gem::Platform.local}"
         output << "Your app has gems that work on these platforms:\n#{platforms.join("\n")}"
 
diff --git a/lib/bundler/cli/show.rb b/lib/bundler/cli/show.rb
index 5eaaba1ef7..2df13db1fa 100644
--- a/lib/bundler/cli/show.rb
+++ b/lib/bundler/cli/show.rb
@@ -18,7 +18,7 @@ module Bundler
 
       if gem_name
         if gem_name == "bundler"
-          path = File.expand_path("../../../..", __FILE__)
+          path = File.expand_path("../../..", __dir__)
         else
           spec = Bundler::CLI::Common.select_spec(gem_name, :regex_match)
           return unless spec
diff --git a/lib/bundler/cli/viz.rb b/lib/bundler/cli/viz.rb
index 644f9b25cf..5c09e00995 100644
--- a/lib/bundler/cli/viz.rb
+++ b/lib/bundler/cli/viz.rb
@@ -23,7 +23,7 @@ module Bundler
       Bundler.ui.warn "Make sure you have the graphviz ruby gem. You can install it with:"
       Bundler.ui.warn "`gem install ruby-graphviz`"
     rescue StandardError => e
-      raise unless e.message =~ /GraphViz not installed or dot not in PATH/
+      raise unless e.message.to_s.include?("GraphViz not installed or dot not in PATH")
       Bundler.ui.error e.message
       Bundler.ui.warn "Please install GraphViz. On a Mac with Homebrew, you can run `brew install graphviz`."
     end
diff --git a/lib/bundler/compact_index_client/cache.rb b/lib/bundler/compact_index_client/cache.rb
index 2d83777139..0b43581c11 100644
--- a/lib/bundler/compact_index_client/cache.rb
+++ b/lib/bundler/compact_index_client/cache.rb
@@ -68,7 +68,7 @@ module Bundler
 
       def info_path(name)
         name = name.to_s
-        if name =~ /[^a-z0-9_-]/
+        if /[^a-z0-9_-]/.match?(name)
           name += "-#{SharedHelpers.digest(:MD5).hexdigest(name).downcase}"
           info_roots.last.join(name)
         else
diff --git a/lib/bundler/compact_index_client/updater.rb b/lib/bundler/compact_index_client/updater.rb
index d9b9cec0d4..0f7bf9bb50 100644
--- a/lib/bundler/compact_index_client/updater.rb
+++ b/lib/bundler/compact_index_client/updater.rb
@@ -20,64 +20,64 @@ module Bundler
 
       def initialize(fetcher)
         @fetcher = fetcher
-        require_relative "../vendored_tmpdir"
       end
 
       def update(local_path, remote_path, retrying = nil)
         headers = {}
 
-        Bundler::Dir.mktmpdir("bundler-compact-index-") do |local_temp_dir|
-          local_temp_path = Pathname.new(local_temp_dir).join(local_path.basename)
+        local_temp_path = local_path.sub(/$/, ".#{$$}")
+        local_temp_path = local_temp_path.sub(/$/, ".retrying") if retrying
+        local_temp_path = local_temp_path.sub(/$/, ".tmp")
 
-          # first try to fetch any new bytes on the existing file
-          if retrying.nil? && local_path.file?
-            SharedHelpers.filesystem_access(local_temp_path) do
-              FileUtils.cp local_path, local_temp_path
-            end
-            headers["If-None-Match"] = etag_for(local_temp_path)
-            headers["Range"] =
-              if local_temp_path.size.nonzero?
-                # Subtract a byte to ensure the range won't be empty.
-                # Avoids 416 (Range Not Satisfiable) responses.
-                "bytes=#{local_temp_path.size - 1}-"
-              else
-                "bytes=#{local_temp_path.size}-"
-              end
-          end
+        # first try to fetch any new bytes on the existing file
+        if retrying.nil? && local_path.file?
+          copy_file local_path, local_temp_path
 
-          response = @fetcher.call(remote_path, headers)
-          return nil if response.is_a?(Net::HTTPNotModified)
+          headers["If-None-Match"] = etag_for(local_temp_path)
+          headers["Range"] =
+            if local_temp_path.size.nonzero?
+              # Subtract a byte to ensure the range won't be empty.
+              # Avoids 416 (Range Not Satisfiable) responses.
+              "bytes=#{local_temp_path.size - 1}-"
+            else
+              "bytes=#{local_temp_path.size}-"
+            end
+        end
 
-          content = response.body
+        response = @fetcher.call(remote_path, headers)
+        return nil if response.is_a?(Net::HTTPNotModified)
 
-          etag = (response["ETag"] || "").gsub(%r{\AW/}, "")
-          correct_response = SharedHelpers.filesystem_access(local_temp_path) do
-            if response.is_a?(Net::HTTPPartialContent) && local_temp_path.size.nonzero?
-              local_temp_path.open("a") {|f| f << slice_body(content, 1..-1) }
+        content = response.body
 
-              etag_for(local_temp_path) == etag
-            else
-              local_temp_path.open("wb") {|f| f << content }
+        etag = (response["ETag"] || "").gsub(%r{\AW/}, "")
+        correct_response = SharedHelpers.filesystem_access(local_temp_path) do
+          if response.is_a?(Net::HTTPPartialContent) && local_temp_path.size.nonzero?
+            local_temp_path.open("a") {|f| f << slice_body(content, 1..-1) }
 
-              etag.length.zero? || etag_for(local_temp_path) == etag
-            end
-          end
+            etag_for(local_temp_path) == etag
+          else
+            local_temp_path.open("wb") {|f| f << content }
 
-          if correct_response
-            SharedHelpers.filesystem_access(local_path) do
-              FileUtils.mv(local_temp_path, local_path)
-            end
-            return nil
+            etag.length.zero? || etag_for(local_temp_path) == etag
           end
+        end
 
-          if retrying
-            raise MisMatchedChecksumError.new(remote_path, etag, etag_for(local_temp_path))
+        if correct_response
+          SharedHelpers.filesystem_access(local_path) do
+            FileUtils.mv(local_temp_path, local_path)
           end
+          return nil
+        end
 
-          update(local_path, remote_path, :retrying)
+        if retrying
+          raise MisMatchedChecksumError.new(remote_path, etag, etag_for(local_temp_path))
         end
+
+        update(local_path, remote_path, :retrying)
       rescue Zlib::GzipFile::Error
         raise Bundler::HTTPError
+      ensure
+        FileUtils.remove_file(local_temp_path) if File.exist?(local_temp_path)
       end
 
       def etag_for(path)
@@ -98,6 +98,20 @@ module Bundler
           SharedHelpers.digest(:MD5).hexdigest(File.read(path))
         end
       end
+
+      private
+
+      def copy_file(source, dest)
+        SharedHelpers.filesystem_access(source, :read) do
+          File.open(source, "r") do |s|
+            SharedHelpers.filesystem_access(dest, :write) do
+              File.open(dest, "wb", s.stat.mode) do |f|
+                IO.copy_stream(s, f)
+              end
+            end
+          end
+        end
+      end
     end
   end
 end
diff --git a/lib/bundler/constants.rb b/lib/bundler/constants.rb
index 2e4ebb37ee..8dd8a53815 100644
--- a/lib/bundler/constants.rb
+++ b/lib/bundler/constants.rb
@@ -2,6 +2,6 @@
 
 module Bundler
   WINDOWS = RbConfig::CONFIG["host_os"] =~ /(msdos|mswin|djgpp|mingw)/
-  FREEBSD = RbConfig::CONFIG["host_os"] =~ /bsd/
+  FREEBSD = RbConfig::CONFIG["host_os"].to_s.include?("bsd")
   NULL    = WINDOWS ? "NUL" : "/dev/null"
 end
diff --git a/lib/bundler/current_ruby.rb b/lib/bundler/current_ruby.rb
index f84d68e262..f009b07ad7 100644
--- a/lib/bundler/current_ruby.rb
+++ b/lib/bundler/current_ruby.rb
@@ -21,6 +21,9 @@ module Bundler
       2.6
       2.7
       3.0
+      3.1
+      3.2
+      3.3
     ].freeze
 
     KNOWN_MAJOR_VERSIONS = KNOWN_MINOR_VERSIONS.map {|v| v.split(".", 2).first }.uniq.freeze
@@ -35,17 +38,18 @@ module Bundler
       rbx
       ruby
       truffleruby
+      windows
       x64_mingw
     ].freeze
 
     def ruby?
       return true if Bundler::GemHelpers.generic_local_platform == Gem::Platform::RUBY
 
-      !mswin? && (RUBY_ENGINE == "ruby" || RUBY_ENGINE == "rbx" || RUBY_ENGINE == "maglev" || RUBY_ENGINE == "truffleruby")
+      !windows? && (RUBY_ENGINE == "ruby" || RUBY_ENGINE == "rbx" || RUBY_ENGINE == "maglev" || RUBY_ENGINE == "truffleruby")
     end
 
     def mri?
-      !mswin? && RUBY_ENGINE == "ruby"
+      !windows? && RUBY_ENGINE == "ruby"
     end
 
     def rbx?
@@ -64,20 +68,28 @@ module Bundler
       RUBY_ENGINE == "truffleruby"
     end
 
-    def mswin?
+    def windows?
       Gem.win_platform?
     end
 
+    def mswin?
+      # For backwards compatibility
+      windows?
+
+      # TODO: This should correctly be:
+      # windows? && Bundler.local_platform != Gem::Platform::RUBY && Bundler.local_platform.os == "mswin32" && Bundler.local_platform.cpu == "x86"
+    end
+
     def mswin64?
-      Gem.win_platform? && Bundler.local_platform != Gem::Platform::RUBY && Bundler.local_platform.os == "mswin64" && Bundler.local_platform.cpu == "x64"
+      windows? && Bundler.local_platform != Gem::Platform::RUBY && Bundler.local_platform.os == "mswin64" && Bundler.local_platform.cpu == "x64"
     end
 
     def mingw?
-      Gem.win_platform? && Bundler.local_platform != Gem::Platform::RUBY && Bundler.local_platform.os == "mingw32" && Bundler.local_platform.cpu != "x64"
+      windows? && Bundler.local_platform != Gem::Platform::RUBY && Bundler.local_platform.os == "mingw32" && Bundler.local_platform.cpu != "x64"
     end
 
     def x64_mingw?
-      Gem.win_platform? && Bundler.local_platform != Gem::Platform::RUBY && Bundler.local_platform.os == "mingw32" && Bundler.local_platform.cpu == "x64"
+      Gem.win_platform? && Bundler.local_platform != Gem::Platform::RUBY && Bundler.local_platform.os.start_with?("mingw") && Bundler.local_platform.cpu == "x64"
     end
 
     (KNOWN_MINOR_VERSIONS + KNOWN_MAJOR_VERSIONS).each do |version|
diff --git a/lib/bundler/definition.rb b/lib/bundler/definition.rb
index 09be2db68c..564530a98c 100644
--- a/lib/bundler/definition.rb
+++ b/lib/bundler/definition.rb
@@ -16,7 +16,6 @@ module Bundler
       :locked_deps,
       :locked_gems,
       :platforms,
-      :requires,
       :ruby_version,
       :lockfile,
       :gemfiles
@@ -70,15 +69,20 @@ module Bundler
       @unlock          = unlock
       @optional_groups = optional_groups
       @remote          = false
+      @prefer_local    = false
       @specs           = nil
       @ruby_version    = ruby_version
       @gemfiles        = gemfiles
 
       @lockfile               = lockfile
       @lockfile_contents      = String.new
+
       @locked_bundler_version = nil
-      @locked_ruby_version    = nil
+      @resolved_bundler_version = nil
+
+      @locked_ruby_version = nil
       @new_platform = nil
+      @removed_platform = nil
 
       if lockfile && File.exist?(lockfile)
         @lockfile_contents = Bundler.read_file(lockfile)
@@ -105,6 +109,7 @@ module Bundler
         @locked_gems    = nil
         @locked_deps    = {}
         @locked_specs   = SpecSet.new([])
+        @originally_locked_specs = @locked_specs
         @locked_sources = []
         @locked_platforms = []
       end
@@ -128,7 +133,7 @@ module Bundler
       end
       @unlocking ||= @unlock[:ruby] ||= (!@locked_ruby_version ^ !@ruby_version)
 
-      add_current_platform unless current_ruby_platform_locked? || Bundler.frozen_bundle?
+      add_current_platform unless Bundler.frozen_bundle?
 
       converge_path_sources_to_gemspec_sources
       @path_changes = converge_paths
@@ -137,31 +142,18 @@ module Bundler
       if @unlock[:conservative]
         @unlock[:gems] ||= @dependencies.map(&:name)
       else
-        eager_unlock = expand_dependencies(@unlock[:gems] || [], true)
-        @unlock[:gems] = @locked_specs.for(eager_unlock, false, false).map(&:name)
+        eager_unlock = (@unlock[:gems] || []).map {|name| Dependency.new(name, ">= 0") }
+        @unlock[:gems] = @locked_specs.for(eager_unlock, false, platforms).map(&:name).uniq
       end
 
       @dependency_changes = converge_dependencies
       @local_changes = converge_locals
 
-      @locked_specs_incomplete_for_platform = !@locked_specs.for(requested_dependencies & expand_dependencies(locked_dependencies), true, true)
-
-      @requires = compute_requires
+      @missing_lockfile_dep = check_missing_lockfile_dep
     end
 
     def gem_version_promoter
-      @gem_version_promoter ||= begin
-        locked_specs =
-          if unlocking? && @locked_specs.empty? && !@lockfile_contents.empty?
-            # Definition uses an empty set of locked_specs to indicate all gems
-            # are unlocked, but GemVersionPromoter needs the locked_specs
-            # for conservative comparison.
-            Bundler::SpecSet.new(@locked_gems.specs)
-          else
-            @locked_specs
-          end
-        GemVersionPromoter.new(locked_specs, @unlock[:gems])
-      end
+      @gem_version_promoter ||= GemVersionPromoter.new
     end
 
     def resolve_only_locally!
@@ -181,6 +173,23 @@ module Bundler
       resolve
     end
 
+    def resolution_mode=(options)
+      if options["local"]
+        @remote = false
+      else
+        @remote = true
+        @prefer_local = options["prefer-local"]
+      end
+    end
+
+    def setup_sources_for_resolve
+      if @remote == false
+        sources.cached!
+      else
+        sources.remote!
+      end
+    end
+
     # For given dependency list returns a SpecSet with Gemspec of all the required
     # dependencies.
     #  1. The method first resolves the dependencies specified in Gemfile
@@ -210,6 +219,8 @@ module Bundler
       true
     rescue BundlerError => e
       @resolve = nil
+      @resolver = nil
+      @resolution_packages = nil
       @specs = nil
       @gem_version_promoter = nil
 
@@ -226,8 +237,16 @@ module Bundler
     end
 
     def current_dependencies
+      filter_relevant(dependencies)
+    end
+
+    def current_locked_dependencies
+      filter_relevant(locked_dependencies)
+    end
+
+    def filter_relevant(dependencies)
       dependencies.select do |d|
-        d.should_include? && !d.gem_platforms(@platforms).empty?
+        d.should_include? && !d.gem_platforms([generic_local_platform]).empty?
       end
     end
 
@@ -235,6 +254,14 @@ module Bundler
       @locked_deps.values
     end
 
+    def new_deps
+      @new_deps ||= @dependencies - locked_dependencies
+    end
+
+    def deleted_deps
+      @deleted_deps ||= locked_dependencies - @dependencies
+    end
+
     def specs_for(groups)
       return specs if groups.empty?
       deps = dependencies_for(groups)
@@ -243,10 +270,9 @@ module Bundler
 
     def dependencies_for(groups)
       groups.map!(&:to_sym)
-      deps = current_dependencies.reject do |d|
+      current_dependencies.reject do |d|
         (d.groups & groups).empty?
       end
-      expand_dependencies(deps)
     end
 
     # Resolve all the dependencies specified in Gemfile. It ensures that
@@ -255,20 +281,24 @@ module Bundler
     #
     # @return [SpecSet] resolved dependencies
     def resolve
-      @resolve ||= begin
-        last_resolve = converge_locked_specs
-        if Bundler.frozen_bundle?
-          Bundler.ui.debug "Frozen, using resolution from the lockfile"
-          last_resolve
-        elsif !unlocking? && nothing_changed?
-          Bundler.ui.debug("Found no changes, using resolution from the lockfile")
-          last_resolve
+      @resolve ||= if Bundler.frozen_bundle?
+        Bundler.ui.debug "Frozen, using resolution from the lockfile"
+        @locked_specs
+      elsif no_resolve_needed?
+        if deleted_deps.any?
+          Bundler.ui.debug "Some dependencies were deleted, using a subset of the resolution from the lockfile"
+          SpecSet.new(filter_specs(@locked_specs, @dependencies - deleted_deps))
         else
-          # Run a resolve against the locally available gems
-          Bundler.ui.debug("Found changes from the lockfile, re-resolving dependencies because #{change_reason}")
-          expanded_dependencies = expand_dependencies(dependencies + metadata_dependencies, true)
-          Resolver.resolve(expanded_dependencies, source_requirements, last_resolve, gem_version_promoter, additional_base_requirements_for_resolve, platforms)
+          Bundler.ui.debug "Found no changes, using resolution from the lockfile"
+          if @removed_platform || @locked_gems.may_include_redundant_platform_specific_gems?
+            SpecSet.new(filter_specs(@locked_specs, @dependencies))
+          else
+            @locked_specs
+          end
         end
+      else
+        Bundler.ui.debug "Found changes from the lockfile, re-resolving dependencies because #{change_reason}"
+        start_resolution
       end
     end
 
@@ -287,11 +317,11 @@ module Bundler
 
       # Convert to \r\n if the existing lock has them
       # i.e., Windows with `git config core.autocrlf=true`
-      contents.gsub!(/\n/, "\r\n") if @lockfile_contents.match("\r\n")
+      contents.gsub!(/\n/, "\r\n") if @lockfile_contents.match?("\r\n")
 
       if @locked_bundler_version
         locked_major = @locked_bundler_version.segments.first
-        current_major = Gem::Version.create(Bundler::VERSION).segments.first
+        current_major = bundler_version_to_lock.segments.first
 
         updating_major = locked_major < current_major
       end
@@ -331,27 +361,16 @@ module Bundler
       end
     end
 
+    def bundler_version_to_lock
+      @resolved_bundler_version || Bundler.gem_version
+    end
+
     def to_lock
       require_relative "lockfile_generator"
       LockfileGenerator.generate(self)
     end
 
     def ensure_equivalent_gemfile_and_lockfile(explicit_flag = false)
-      msg = String.new
-      msg << "You are trying to install in deployment mode after changing\n" \
-             "your Gemfile. Run `bundle install` elsewhere and add the\n" \
-             "updated #{Bundler.default_lockfile.relative_path_from(SharedHelpers.pwd)} to version control."
-
-      unless explicit_flag
-        suggested_command = if Bundler.settings.locations("frozen").keys.&([:global, :local]).any?
-          "bundle config unset frozen"
-        elsif Bundler.settings.locations("deployment").keys.&([:global, :local]).any?
-          "bundle config unset deployment"
-        end
-        msg << "\n\nIf this is a development machine, remove the #{Bundler.default_gemfile} " \
-               "freeze \nby running `#{suggested_command}`."
-      end
-
       added =   []
       deleted = []
       changed = []
@@ -361,39 +380,40 @@ module Bundler
       added.concat new_platforms.map {|p| "* platform: #{p}" }
       deleted.concat deleted_platforms.map {|p| "* platform: #{p}" }
 
-      new_deps = @dependencies - locked_dependencies
-      deleted_deps = locked_dependencies - @dependencies
-
       added.concat new_deps.map {|d| "* #{pretty_dep(d)}" } if new_deps.any?
       deleted.concat deleted_deps.map {|d| "* #{pretty_dep(d)}" } if deleted_deps.any?
 
       both_sources = Hash.new {|h, k| h[k] = [] }
-      @dependencies.each {|d| both_sources[d.name][0] = d }
-
-      locked_dependencies.each do |d|
-        next if !Bundler.feature_flag.bundler_3_mode? && @locked_specs[d.name].empty?
-
-        both_sources[d.name][1] = d
-      end
+      current_dependencies.each {|d| both_sources[d.name][0] = d }
+      current_locked_dependencies.each {|d| both_sources[d.name][1] = d }
 
       both_sources.each do |name, (dep, lock_dep)|
         next if dep.nil? || lock_dep.nil?
 
-        gemfile_source = dep.source || sources.default_source
-        lock_source = lock_dep.source || sources.default_source
+        gemfile_source = dep.source || default_source
+        lock_source = lock_dep.source || default_source
         next if lock_source.include?(gemfile_source)
 
-        gemfile_source_name = dep.source ? gemfile_source.identifier : "no specified source"
-        lockfile_source_name = lock_dep.source ? lock_source.identifier : "no specified source"
+        gemfile_source_name = dep.source ? gemfile_source.to_gemfile : "no specified source"
+        lockfile_source_name = lock_dep.source ? lock_source.to_gemfile : "no specified source"
         changed << "* #{name} from `#{lockfile_source_name}` to `#{gemfile_source_name}`"
       end
 
       reason = change_reason
-      msg << "\n\n#{reason.split(", ").map(&:capitalize).join("\n")}" unless reason.strip.empty?
+      msg = String.new
+      msg << "#{reason.capitalize.strip}, but the lockfile can't be updated because frozen mode is set"
       msg << "\n\nYou have added to the Gemfile:\n" << added.join("\n") if added.any?
       msg << "\n\nYou have deleted from the Gemfile:\n" << deleted.join("\n") if deleted.any?
       msg << "\n\nYou have changed in the Gemfile:\n" << changed.join("\n") if changed.any?
-      msg << "\n"
+      msg << "\n\nRun `bundle install` elsewhere and add the updated #{Bundler.default_lockfile.relative_path_from(SharedHelpers.pwd)} to version control.\n"
+
+      unless explicit_flag
+        suggested_command = unless Bundler.settings.locations("frozen").keys.include?(:env)
+          "bundle config set frozen false"
+        end
+        msg << "If this is a development machine, remove the #{Bundler.default_gemfile.relative_path_from(SharedHelpers.pwd)} " \
+               "freeze by running `#{suggested_command}`." if suggested_command
+      end
 
       raise ProductionError, msg if added.any? || deleted.any? || changed.any? || !nothing_changed?
     end
@@ -442,7 +462,9 @@ module Bundler
     end
 
     def remove_platform(platform)
-      return if @platforms.delete(Gem::Platform.new(platform))
+      removed_platform = @platforms.delete(Gem::Platform.new(platform))
+      @removed_platform ||= removed_platform
+      return if removed_platform
       raise InvalidOption, "Unable to remove the platform `#{platform}` since the only platforms are #{@platforms.join ", "}"
     end
 
@@ -456,7 +478,11 @@ module Bundler
     private :sources
 
     def nothing_changed?
-      !@source_changes && !@dependency_changes && !@new_platform && !@path_changes && !@local_changes && !@locked_specs_incomplete_for_platform
+      !@source_changes && !@dependency_changes && !@new_platform && !@path_changes && !@local_changes && !@missing_lockfile_dep && !@unlocking_bundler
+    end
+
+    def no_resolve_needed?
+      !unlocking? && nothing_changed?
     end
 
     def unlocking?
@@ -465,6 +491,34 @@ module Bundler
 
     private
 
+    def resolver
+      @resolver ||= Resolver.new(resolution_packages, gem_version_promoter)
+    end
+
+    def expanded_dependencies
+      dependencies_with_bundler + metadata_dependencies
+    end
+
+    def dependencies_with_bundler
+      return dependencies unless @unlocking_bundler
+      return dependencies if dependencies.map(&:name).include?("bundler")
+
+      [Dependency.new("bundler", @unlocking_bundler)] + dependencies
+    end
+
+    def resolution_packages
+      @resolution_packages ||= begin
+        last_resolve = converge_locked_specs
+        remove_ruby_from_platforms_if_necessary!(current_dependencies)
+        packages = Resolver::Base.new(source_requirements, expanded_dependencies, last_resolve, @platforms, :locked_specs => @originally_locked_specs, :unlock => @unlock[:gems], :prerelease => gem_version_promoter.pre?)
+        additional_base_requirements_for_resolve(packages, last_resolve)
+      end
+    end
+
+    def filter_specs(specs, deps)
+      SpecSet.new(specs).for(deps, false, platforms)
+    end
+
     def materialize(dependencies)
       specs = resolve.materialize(dependencies)
       missing_specs = specs.missing_specs
@@ -479,19 +533,62 @@ module Bundler
                              "removed in order to install."
         end
 
-        raise GemNotFound, "Could not find #{missing_specs.map(&:full_name).join(", ")} in any of the sources"
+        missing_specs_list = missing_specs.group_by(&:source).map do |source, missing_specs_for_source|
+          "#{missing_specs_for_source.map(&:full_name).join(", ")} in #{source}"
+        end
+
+        raise GemNotFound, "Could not find #{missing_specs_list.join(" nor ")}"
       end
 
-      unless specs["bundler"].any?
-        bundler = sources.metadata_source.specs.search(Gem::Dependency.new("bundler", VERSION)).last
-        specs["bundler"] = bundler
+      incomplete_specs = specs.incomplete_specs
+      loop do
+        break if incomplete_specs.empty?
+
+        Bundler.ui.debug("The lockfile does not have all gems needed for the current platform though, Bundler will still re-resolve dependencies")
+        setup_sources_for_resolve
+        resolution_packages.delete(incomplete_specs)
+        @resolve = start_resolution
+        specs = resolve.materialize(dependencies)
+
+        still_incomplete_specs = specs.incomplete_specs
+
+        if still_incomplete_specs == incomplete_specs
+          package = resolution_packages.get_package(incomplete_specs.first.name)
+          resolver.raise_not_found! package
+        end
+
+        incomplete_specs = still_incomplete_specs
       end
 
+      bundler = sources.metadata_source.specs.search(["bundler", Bundler.gem_version]).last
+      specs["bundler"] = bundler
+
       specs
     end
 
+    def start_resolution
+      result = resolver.start
+
+      @resolved_bundler_version = result.find {|spec| spec.name == "bundler" }&.version
+
+      SpecSet.new(SpecSet.new(result).for(dependencies, false, @platforms))
+    end
+
     def precompute_source_requirements_for_indirect_dependencies?
-      @remote && sources.non_global_rubygems_sources.all?(&:dependency_api_available?) && !sources.aggregate_global_source?
+      sources.non_global_rubygems_sources.all?(&:dependency_api_available?) && !sources.aggregate_global_source?
+    end
+
+    def pin_locally_available_names(source_requirements)
+      source_requirements.each_with_object({}) do |(name, original_source), new_source_requirements|
+        local_source = original_source.dup
+        local_source.local_only!
+
+        new_source_requirements[name] = if local_source.specs.search(name).any?
+          local_source
+        else
+          original_source
+        end
+      end
     end
 
     def current_ruby_platform_locked?
@@ -508,6 +605,8 @@ module Bundler
     end
 
     def add_current_platform
+      return if current_ruby_platform_locked?
+
       add_platform(local_platform)
     end
 
@@ -529,12 +628,13 @@ module Bundler
         [@new_platform, "you added a new platform to your gemfile"],
         [@path_changes, "the gemspecs for path gems changed"],
         [@local_changes, "the gemspecs for git local gems changed"],
-        [@locked_specs_incomplete_for_platform, "the lockfile does not have all gems needed for the current platform"],
+        [@missing_lockfile_dep, "your lock file is missing \"#{@missing_lockfile_dep}\""],
+        [@unlocking_bundler, "an update to the version of Bundler itself was requested"],
       ].select(&:first).map(&:last).join(", ")
     end
 
-    def pretty_dep(dep, source = false)
-      SharedHelpers.pretty_dependency(dep, source)
+    def pretty_dep(dep)
+      SharedHelpers.pretty_dependency(dep)
     end
 
     # Check if the specs of the given source changed
@@ -571,8 +671,8 @@ module Bundler
 
       Bundler.settings.local_overrides.map do |k, v|
         spec   = @dependencies.find {|s| s.name == k }
-        source = spec && spec.source
-        if source && source.respond_to?(:local_override!)
+        source = spec&.source
+        if source&.respond_to?(:local_override!)
           source.unlock! if @unlock[:gems].include?(spec.name)
           locals << [source, source.local_override!(v)]
         end
@@ -584,6 +684,26 @@ module Bundler
       !sources_with_changes.each {|source| @unlock[:sources] << source.name }.empty?
     end
 
+    def check_missing_lockfile_dep
+      all_locked_specs = @locked_specs.map(&:name) << "bundler"
+
+      missing = @locked_specs.select do |s|
+        s.dependencies.any? {|dep| !all_locked_specs.include?(dep.name) }
+      end
+
+      if missing.any?
+        @locked_specs.delete(missing)
+
+        return missing.first.name
+      end
+
+      return if @dependency_changes
+
+      current_dependencies.find do |d|
+        @locked_specs[d.name].empty? && d.name != "bundler"
+      end&.name
+    end
+
     def converge_paths
       sources.path_sources.any? do |source|
         specs_changed?(source)
@@ -637,6 +757,8 @@ module Bundler
           dep.source = sources.get(dep.source)
         end
 
+        next if unlocking?
+
         unless locked_dep = @locked_deps[dep.name]
           changes = true
           next
@@ -662,7 +784,9 @@ module Bundler
     # commonly happen if the Gemfile has changed since the lockfile was last
     # generated
     def converge_locked_specs
-      resolve = converge_specs(@locked_specs)
+      converged = converge_specs(@locked_specs)
+
+      resolve = SpecSet.new(converged.reject {|s| @unlock[:gems].include?(s.name) })
 
       diff = nil
 
@@ -680,101 +804,71 @@ module Bundler
     end
 
     def converge_specs(specs)
-      deps = []
       converged = []
+      deps = []
 
-      @dependencies.each do |dep|
-        if specs[dep].any? {|s| s.satisfies?(dep) && (!dep.source || s.source.include?(dep.source)) }
-          deps << dep
-        end
-      end
+      @specs_that_changed_sources = []
 
       specs.each do |s|
-        # Replace the locked dependency's source with the equivalent source from the Gemfile
+        name = s.name
         dep = @dependencies.find {|d| s.satisfies?(d) }
+        lockfile_source = s.source
 
-        s.source = (dep && dep.source) || sources.get(s.source) || sources.default_source unless Bundler.frozen_bundle?
+        if dep
+          gemfile_source = dep.source || default_source
 
-        next if @unlock[:sources].include?(s.source.name)
+          @specs_that_changed_sources << s if gemfile_source != lockfile_source
+          deps << dep if !dep.source || lockfile_source.include?(dep.source)
+          @unlock[:gems] << name if lockfile_source.include?(dep.source) && lockfile_source != gemfile_source
 
-        # If the spec is from a path source and it doesn't exist anymore
-        # then we unlock it.
+          # Replace the locked dependency's source with the equivalent source from the Gemfile
+          s.source = gemfile_source
+        else
+          # Replace the locked dependency's source with the default source, if the locked source is no longer in the Gemfile
+          s.source = default_source unless sources.get(lockfile_source)
+        end
+
+        next if @unlock[:sources].include?(s.source.name)
 
         # Path sources have special logic
         if s.source.instance_of?(Source::Path) || s.source.instance_of?(Source::Gemspec)
           new_specs = begin
             s.source.specs
-          rescue PathError, GitError
+          rescue PathError
             # if we won't need the source (according to the lockfile),
-            # don't error if the path/git source isn't available
+            # don't error if the path source isn't available
             next if specs.
-                    for(requested_dependencies, false, true).
+                    for(requested_dependencies, false).
                     none? {|locked_spec| locked_spec.source == s.source }
 
             raise
           end
 
           new_spec = new_specs[s].first
-
-          # If the spec is no longer in the path source, unlock it. This
-          # commonly happens if the version changed in the gemspec
-          next unless new_spec
-
-          s.dependencies.replace(new_spec.dependencies)
+          if new_spec
+            s.dependencies.replace(new_spec.dependencies)
+          else
+            # If the spec is no longer in the path source, unlock it. This
+            # commonly happens if the version changed in the gemspec
+            @unlock[:gems] << name
+          end
         end
 
-        if dep.nil? && requested_dependencies.find {|d| s.name == d.name }
+        if dep.nil? && requested_dependencies.find {|d| name == d.name }
           @unlock[:gems] << s.name
         else
           converged << s
         end
       end
 
-      resolve = SpecSet.new(converged)
-      SpecSet.new(resolve.for(expand_dependencies(deps, true), false, false).reject{|s| @unlock[:gems].include?(s.name) })
+      filter_specs(converged, deps)
     end
 
     def metadata_dependencies
-      @metadata_dependencies ||= begin
-        ruby_versions = ruby_version_requirements(@ruby_version)
-        [
-          Dependency.new("Ruby\0", ruby_versions),
-          Dependency.new("RubyGems\0", Gem::VERSION),
-        ]
-      end
-    end
-
-    def ruby_version_requirements(ruby_version)
-      return [] unless ruby_version
-      if ruby_version.patchlevel
-        [ruby_version.to_gem_version_with_patchlevel]
-      else
-        ruby_version.versions.map do |version|
-          requirement = Gem::Requirement.new(version)
-          if requirement.exact?
-            "~> #{version}.0"
-          else
-            requirement
-          end
-        end
-      end
-    end
-
-    def expand_dependencies(dependencies, remote = false)
-      deps = []
-      dependencies.each do |dep|
-        dep = Dependency.new(dep, ">= 0") unless dep.respond_to?(:name)
-        next unless remote || dep.current_platform?
-        target_platforms = dep.gem_platforms(remote ? @platforms : [generic_local_platform])
-        deps += expand_dependency_with_platforms(dep, target_platforms)
-      end
-      deps
-    end
-
-    def expand_dependency_with_platforms(dep, platforms)
-      platforms.map do |p|
-        DepProxy.get_proxy(dep, p)
-      end
+      @metadata_dependencies ||= [
+        Dependency.new("Ruby\0", Gem.ruby_version),
+        Dependency.new("RubyGems\0", Gem::VERSION),
+      ]
     end
 
     def source_requirements
@@ -782,7 +876,9 @@ module Bundler
       # specs will be available later when the resolver knows where to
       # look for that gemspec (or its dependencies)
       source_requirements = if precompute_source_requirements_for_indirect_dependencies?
-        { :default => sources.default_source }.merge(source_map.all_requirements)
+        all_requirements = source_map.all_requirements
+        all_requirements = pin_locally_available_names(all_requirements) if @prefer_local
+        { :default => default_source }.merge(all_requirements)
       else
         { :default => Source::RubygemsAggregate.new(sources, source_map) }.merge(source_map.direct_requirements)
       end
@@ -790,20 +886,44 @@ module Bundler
       metadata_dependencies.each do |dep|
         source_requirements[dep.name] = sources.metadata_source
       end
-      source_requirements[:default_bundler] = source_requirements["bundler"] || sources.default_source
-      source_requirements["bundler"] = sources.metadata_source # needs to come last to override
+
+      default_bundler_source = source_requirements["bundler"] || default_source
+
+      if @unlocking_bundler
+        default_bundler_source.add_dependency_names("bundler")
+      else
+        source_requirements[:default_bundler] = default_bundler_source
+        source_requirements["bundler"] = sources.metadata_source # needs to come last to override
+      end
+
+      verify_changed_sources!
       source_requirements
     end
 
+    def default_source
+      sources.default_source
+    end
+
+    def verify_changed_sources!
+      @specs_that_changed_sources.each do |s|
+        if s.source.specs.search(s.name).empty?
+          raise GemNotFound, "Could not find gem '#{s.name}' in #{s.source}"
+        end
+      end
+    end
+
     def requested_groups
-      groups - Bundler.settings[:without] - @optional_groups + Bundler.settings[:with]
+      values = groups - Bundler.settings[:without] - @optional_groups + Bundler.settings[:with]
+      values &= Bundler.settings[:only] unless Bundler.settings[:only].empty?
+      values
     end
 
     def lockfiles_equal?(current, proposed, preserve_unknown_sections)
       if preserve_unknown_sections
         sections_to_ignore = LockfileParser.sections_to_ignore(@locked_bundler_version)
         sections_to_ignore += LockfileParser.unknown_sections_in_lockfile(current)
-        sections_to_ignore += LockfileParser::ENVIRONMENT_VERSION_SECTIONS
+        sections_to_ignore << LockfileParser::RUBY
+        sections_to_ignore << LockfileParser::BUNDLED unless @unlocking_bundler
         pattern = /#{Regexp.union(sections_to_ignore)}\n(\s{2,}.*\n)+/
         whitespace_cleanup = /\n{2,}/
         current = current.gsub(pattern, "\n").gsub(whitespace_cleanup, "\n\n").strip
@@ -812,24 +932,26 @@ module Bundler
       current == proposed
     end
 
-    def compute_requires
-      dependencies.reduce({}) do |requires, dep|
-        next requires unless dep.should_include?
-        requires[dep.name] = Array(dep.autorequire || dep.name).map do |file|
-          # Allow `require: true` as an alias for `require: <name>`
-          file == true ? dep.name : file
-        end
-        requires
+    def additional_base_requirements_for_resolve(resolution_packages, last_resolve)
+      return resolution_packages unless @locked_gems && !sources.expired_sources?(@locked_gems.sources)
+      converge_specs(@originally_locked_specs - last_resolve).each do |locked_spec|
+        next if locked_spec.source.is_a?(Source::Path)
+        resolution_packages.base_requirements[locked_spec.name] = Gem::Requirement.new(">= #{locked_spec.version}")
       end
+      resolution_packages
     end
 
-    def additional_base_requirements_for_resolve
-      return [] unless @locked_gems && unlocking? && !sources.expired_sources?(@locked_gems.sources)
-      converge_specs(@originally_locked_specs).map do |locked_spec|
-        name = locked_spec.name
-        dep = Gem::Dependency.new(name, ">= #{locked_spec.version}")
-        DepProxy.get_proxy(dep, locked_spec.platform)
-      end
+    def remove_ruby_from_platforms_if_necessary!(dependencies)
+      return if Bundler.frozen_bundle? ||
+                Bundler.local_platform == Gem::Platform::RUBY ||
+                !platforms.include?(Gem::Platform::RUBY) ||
+                (@new_platform && platforms.last == Gem::Platform::RUBY) ||
+                @path_changes ||
+                @dependency_changes ||
+                !@originally_locked_specs.incomplete_ruby_specs?(dependencies)
+
+      remove_platform(Gem::Platform::RUBY)
+      add_current_platform
     end
 
     def source_map
diff --git a/lib/bundler/dep_proxy.rb b/lib/bundler/dep_proxy.rb
deleted file mode 100644
index a32dc37b49..0000000000
--- a/lib/bundler/dep_proxy.rb
+++ /dev/null
@@ -1,55 +0,0 @@
-# frozen_string_literal: true
-
-module Bundler
-  class DepProxy
-    attr_reader :__platform, :dep
-
-    @proxies = {}
-
-    def self.get_proxy(dep, platform)
-      @proxies[[dep, platform]] ||= new(dep, platform).freeze
-    end
-
-    def initialize(dep, platform)
-      @dep = dep
-      @__platform = platform
-    end
-
-    private_class_method :new
-
-    alias_method :eql?, :==
-
-    def type
-      @dep.type
-    end
-
-    def name
-      @dep.name
-    end
-
-    def requirement
-      @dep.requirement
-    end
-
-    def to_s
-      s = name.dup
-      s << " (#{requirement})" unless requirement == Gem::Requirement.default
-      s << " #{__platform}" unless __platform == Gem::Platform::RUBY
-      s
-    end
-
-    def dup
-      raise NoMethodError.new("DepProxy cannot be duplicated")
-    end
-
-    def clone
-      raise NoMethodError.new("DepProxy cannot be cloned")
-    end
-
-    private
-
-    def method_missing(*args, &blk)
-      @dep.send(*args, &blk)
-    end
-  end
-end
diff --git a/lib/bundler/dependency.rb b/lib/bundler/dependency.rb
index 94e85053dd..5f17943629 100644
--- a/lib/bundler/dependency.rb
+++ b/lib/bundler/dependency.rb
@@ -7,72 +7,24 @@ require_relative "rubygems_ext"
 module Bundler
   class Dependency < Gem::Dependency
     attr_reader :autorequire
-    attr_reader :groups, :platforms, :gemfile, :git, :github, :branch, :ref
+    attr_reader :groups, :platforms, :gemfile, :path, :git, :github, :branch, :ref
 
+    ALL_RUBY_VERSIONS = ((18..27).to_a + (30..33).to_a).freeze
     PLATFORM_MAP = {
-      :ruby     => Gem::Platform::RUBY,
-      :ruby_18  => Gem::Platform::RUBY,
-      :ruby_19  => Gem::Platform::RUBY,
-      :ruby_20  => Gem::Platform::RUBY,
-      :ruby_21  => Gem::Platform::RUBY,
-      :ruby_22  => Gem::Platform::RUBY,
-      :ruby_23  => Gem::Platform::RUBY,
-      :ruby_24  => Gem::Platform::RUBY,
-      :ruby_25  => Gem::Platform::RUBY,
-      :ruby_26  => Gem::Platform::RUBY,
-      :mri      => Gem::Platform::RUBY,
-      :mri_18   => Gem::Platform::RUBY,
-      :mri_19   => Gem::Platform::RUBY,
-      :mri_20   => Gem::Platform::RUBY,
-      :mri_21   => Gem::Platform::RUBY,
-      :mri_22   => Gem::Platform::RUBY,
-      :mri_23   => Gem::Platform::RUBY,
-      :mri_24   => Gem::Platform::RUBY,
-      :mri_25   => Gem::Platform::RUBY,
-      :mri_26   => Gem::Platform::RUBY,
-      :rbx      => Gem::Platform::RUBY,
-      :truffleruby => Gem::Platform::RUBY,
-      :jruby    => Gem::Platform::JAVA,
-      :jruby_18 => Gem::Platform::JAVA,
-      :jruby_19 => Gem::Platform::JAVA,
-      :mswin    => Gem::Platform::MSWIN,
-      :mswin_18 => Gem::Platform::MSWIN,
-      :mswin_19 => Gem::Platform::MSWIN,
-      :mswin_20 => Gem::Platform::MSWIN,
-      :mswin_21 => Gem::Platform::MSWIN,
-      :mswin_22 => Gem::Platform::MSWIN,
-      :mswin_23 => Gem::Platform::MSWIN,
-      :mswin_24 => Gem::Platform::MSWIN,
-      :mswin_25 => Gem::Platform::MSWIN,
-      :mswin_26 => Gem::Platform::MSWIN,
-      :mswin64    => Gem::Platform::MSWIN64,
-      :mswin64_19 => Gem::Platform::MSWIN64,
-      :mswin64_20 => Gem::Platform::MSWIN64,
-      :mswin64_21 => Gem::Platform::MSWIN64,
-      :mswin64_22 => Gem::Platform::MSWIN64,
-      :mswin64_23 => Gem::Platform::MSWIN64,
-      :mswin64_24 => Gem::Platform::MSWIN64,
-      :mswin64_25 => Gem::Platform::MSWIN64,
-      :mswin64_26 => Gem::Platform::MSWIN64,
-      :mingw    => Gem::Platform::MINGW,
-      :mingw_18 => Gem::Platform::MINGW,
-      :mingw_19 => Gem::Platform::MINGW,
-      :mingw_20 => Gem::Platform::MINGW,
-      :mingw_21 => Gem::Platform::MINGW,
-      :mingw_22 => Gem::Platform::MINGW,
-      :mingw_23 => Gem::Platform::MINGW,
-      :mingw_24 => Gem::Platform::MINGW,
-      :mingw_25 => Gem::Platform::MINGW,
-      :mingw_26 => Gem::Platform::MINGW,
-      :x64_mingw    => Gem::Platform::X64_MINGW,
-      :x64_mingw_20 => Gem::Platform::X64_MINGW,
-      :x64_mingw_21 => Gem::Platform::X64_MINGW,
-      :x64_mingw_22 => Gem::Platform::X64_MINGW,
-      :x64_mingw_23 => Gem::Platform::X64_MINGW,
-      :x64_mingw_24 => Gem::Platform::X64_MINGW,
-      :x64_mingw_25 => Gem::Platform::X64_MINGW,
-      :x64_mingw_26 => Gem::Platform::X64_MINGW,
-    }.freeze
+      :ruby => [Gem::Platform::RUBY, ALL_RUBY_VERSIONS],
+      :mri => [Gem::Platform::RUBY, ALL_RUBY_VERSIONS],
+      :rbx => [Gem::Platform::RUBY],
+      :truffleruby => [Gem::Platform::RUBY],
+      :jruby => [Gem::Platform::JAVA, [18, 19]],
+      :windows => [Gem::Platform::WINDOWS, ALL_RUBY_VERSIONS],
+      :mswin => [Gem::Platform::MSWIN,     ALL_RUBY_VERSIONS],
+      :mswin64 => [Gem::Platform::MSWIN64, ALL_RUBY_VERSIONS - [18]],
+      :mingw => [Gem::Platform::MINGW, ALL_RUBY_VERSIONS],
+      :x64_mingw => [Gem::Platform::X64_MINGW, ALL_RUBY_VERSIONS - [18, 19]],
+    }.each_with_object({}) do |(platform, spec), hash|
+      hash[platform] = spec[0]
+      spec[1]&.each {|version| hash[:"#{platform}_#{version}"] = spec[0] }
+    end.freeze
 
     def initialize(name, version, options = {}, &blk)
       type = options["type"] || :runtime
@@ -81,6 +33,7 @@ module Bundler
       @autorequire    = nil
       @groups         = Array(options["group"] || :default).map(&:to_sym)
       @source         = options["source"]
+      @path           = options["path"]
       @git            = options["git"]
       @github         = options["github"]
       @branch         = options["branch"]
@@ -89,6 +42,7 @@ module Bundler
       @env            = options["env"]
       @should_include = options.fetch("should_include", true)
       @gemfile        = options["gemfile"]
+      @force_ruby_platform = options["force_ruby_platform"] if options.key?("force_ruby_platform")
 
       @autorequire = Array(options["require"] || []) if options.key?("require")
     end
@@ -96,13 +50,14 @@ module Bundler
     # Returns the platforms this dependency is valid for, in the same order as
     # passed in the `valid_platforms` parameter
     def gem_platforms(valid_platforms)
+      return [Gem::Platform::RUBY] if force_ruby_platform
       return valid_platforms if @platforms.empty?
 
       valid_platforms.select {|p| expanded_platforms.include?(GemHelpers.generic(p)) }
     end
 
     def expanded_platforms
-      @expanded_platforms ||= @platforms.map {|pl| PLATFORM_MAP[pl] }.compact.uniq
+      @expanded_platforms ||= @platforms.map {|pl| PLATFORM_MAP[pl] }.compact.flatten.uniq
     end
 
     def should_include?
@@ -130,7 +85,7 @@ module Bundler
     def to_lock
       out = super
       out << "!" if source
-      out << "\n"
+      out
     end
 
     def specific?
diff --git a/lib/bundler/digest.rb b/lib/bundler/digest.rb
index 759f609416..f11f5edd38 100644
--- a/lib/bundler/digest.rb
+++ b/lib/bundler/digest.rb
@@ -43,7 +43,7 @@ module Bundler
               f = (b ^ c ^ d)
               k = 0xCA62C1D6
             end
-            t = SHA1_MASK & (SHA1_MASK & rotate(a, 5) + f + e + k + w[i])
+            t = SHA1_MASK & rotate(a, 5) + f + e + k + w[i]
             a, b, c, d, e = t, a, SHA1_MASK & rotate(b, 30), c, d # rubocop:disable Style/ParallelAssignment
           end
           mutated = [a, b, c, d, e]
diff --git a/lib/bundler/dsl.rb b/lib/bundler/dsl.rb
index f7922b1fba..03c80a408c 100644
--- a/lib/bundler/dsl.rb
+++ b/lib/bundler/dsl.rb
@@ -16,7 +16,7 @@ module Bundler
     VALID_PLATFORMS = Bundler::Dependency::PLATFORM_MAP.keys.freeze
 
     VALID_KEYS = %w[group groups git path glob name branch ref tag require submodules
-                    platform platforms type source install_if gemfile].freeze
+                    platform platforms type source install_if gemfile force_ruby_platform].freeze
 
     GITHUB_PULL_REQUEST_URL = %r{\Ahttps://github\.com/([A-Za-z0-9_\-\.]+/[A-Za-z0-9_\-\.]+)/pull/(\d+)\z}.freeze
 
@@ -41,12 +41,12 @@ module Bundler
     end
 
     def eval_gemfile(gemfile, contents = nil)
-      expanded_gemfile_path = Pathname.new(gemfile).expand_path(@gemfile && @gemfile.parent)
+      expanded_gemfile_path = Pathname.new(gemfile).expand_path(@gemfile&.parent)
       original_gemfile = @gemfile
       @gemfile = expanded_gemfile_path
       @gemfiles << expanded_gemfile_path
       contents ||= Bundler.read_file(@gemfile.to_s)
-      instance_eval(contents.dup.tap{|x| x.untaint if RUBY_VERSION < "2.7" }, gemfile.to_s, 1)
+      instance_eval(contents.dup.tap {|x| x.untaint if RUBY_VERSION < "2.7" }, gemfile.to_s, 1)
     rescue Exception => e # rubocop:disable Lint/RescueException
       message = "There was an error " \
         "#{e.is_a?(GemfileEvalError) ? "evaluating" : "parsing"} " \
@@ -67,7 +67,6 @@ module Bundler
 
       gemspecs = Gem::Util.glob_files_in_dir("{,*}.gemspec", expanded_path).map {|g| Bundler.load_gemspec(g) }.compact
       gemspecs.reject! {|s| s.name != name } if name
-      Index.sort_specs(gemspecs)
       specs_by_name_and_version = gemspecs.group_by {|s| [s.name, s.version] }
 
       case specs_by_name_and_version.size
@@ -124,19 +123,17 @@ module Bundler
             raise GemfileError, "You cannot specify the same gem twice with different version requirements.\n" \
                             "You specified: #{current.name} (#{current.requirement}) and #{dep.name} (#{dep.requirement})" \
                              "#{update_prompt}"
+          elsif current.source != dep.source
+            return if dep.type == :development
+            raise GemfileError, "You cannot specify the same gem twice coming from different sources.\n" \
+                            "You specified that #{dep.name} (#{dep.requirement}) should come from " \
+                            "#{current.source || "an unspecified source"} and #{dep.source}\n"
           else
             Bundler.ui.warn "Your Gemfile lists the gem #{current.name} (#{current.requirement}) more than once.\n" \
                             "You should probably keep only one of them.\n" \
                             "Remove any duplicate entries and specify the gem only once.\n" \
                             "While it's not a problem now, it could cause errors if you change the version of one of them later."
           end
-
-          if current.source != dep.source
-            return if dep.type == :development
-            raise GemfileError, "You cannot specify the same gem twice coming from different sources.\n" \
-                            "You specified that #{dep.name} (#{dep.requirement}) should come from " \
-                            "#{current.source || "an unspecified source"} and #{dep.source}\n"
-          end
         end
       end
 
@@ -280,8 +277,8 @@ module Bundler
         if repo_name =~ GITHUB_PULL_REQUEST_URL
           {
             "git" => "https://github.com/#{$1}.git",
-            "branch" => "refs/pull/#{$2}/head",
-            "ref" => nil,
+            "branch" => nil,
+            "ref" => "refs/pull/#{$2}/head",
             "tag" => nil,
           }
         else
@@ -327,7 +324,7 @@ module Bundler
       if name.is_a?(Symbol)
         raise GemfileError, %(You need to specify gem names as Strings. Use 'gem "#{name}"' instead)
       end
-      if name =~ /\s/
+      if /\s/.match?(name)
         raise GemfileError, %('#{name}' is not a valid gem name because it contains whitespace)
       end
       raise GemfileError, %(an empty gem name is not valid) if name.empty?
@@ -467,12 +464,12 @@ module Bundler
 
     def multiple_global_source_warning
       if Bundler.feature_flag.bundler_3_mode?
-        msg = "This Gemfile contains multiple primary sources. " \
+        msg = "This Gemfile contains multiple global sources. " \
           "Each source after the first must include a block to indicate which gems " \
           "should come from that source"
         raise GemfileEvalError, msg
       else
-        Bundler::SharedHelpers.major_deprecation 2, "Your Gemfile contains multiple primary sources. " \
+        Bundler::SharedHelpers.major_deprecation 2, "Your Gemfile contains multiple global sources. " \
           "Using `source` more than once without a block is a security risk, and " \
           "may result in installing unexpected gems. To resolve this warning, use " \
           "a block to indicate which gems should come from the secondary source."
@@ -513,9 +510,7 @@ module Bundler
       #         be raised.
       #
       def contents
-        @contents ||= begin
-          dsl_path && File.exist?(dsl_path) && File.read(dsl_path)
-        end
+        @contents ||= dsl_path && File.exist?(dsl_path) && File.read(dsl_path)
       end
 
       # The message of the exception reports the content of podspec for the
diff --git a/lib/bundler/endpoint_specification.rb b/lib/bundler/endpoint_specification.rb
index f3260a38e6..863544b1f9 100644
--- a/lib/bundler/endpoint_specification.rb
+++ b/lib/bundler/endpoint_specification.rb
@@ -3,7 +3,7 @@
 module Bundler
   # used for Creating Specifications from the Gemcutter Endpoint
   class EndpointSpecification < Gem::Specification
-    include MatchPlatform
+    include MatchRemoteMetadata
 
     attr_reader :name, :version, :platform, :checksum
     attr_accessor :source, :remote, :dependencies
@@ -12,7 +12,7 @@ module Bundler
       super()
       @name         = name
       @version      = Gem::Version.create version
-      @platform     = platform
+      @platform     = Gem::Platform.new(platform)
       @spec_fetcher = spec_fetcher
       @dependencies = dependencies.map {|dep, reqs| build_dependency(dep, reqs) }
 
@@ -22,14 +22,6 @@ module Bundler
       parse_metadata(metadata)
     end
 
-    def required_ruby_version
-      @required_ruby_version ||= _remote_specification.required_ruby_version
-    end
-
-    def required_rubygems_version
-      @required_rubygems_version ||= _remote_specification.required_rubygems_version
-    end
-
     def fetch_platform
       @platform
     end
diff --git a/lib/bundler/env.rb b/lib/bundler/env.rb
index 1763035a8a..7b1152930e 100644
--- a/lib/bundler/env.rb
+++ b/lib/bundler/env.rb
@@ -75,7 +75,7 @@ module Bundler
     end
 
     def self.git_version
-      Bundler::Source::Git::GitProxy.new(nil, nil, nil).full_version
+      Bundler::Source::Git::GitProxy.new(nil, nil).full_version
     rescue Bundler::Source::Git::GitNotInstalledError
       "not installed"
     end
@@ -122,7 +122,7 @@ module Bundler
         specs = Bundler.rubygems.find_name(name)
         out << ["  #{name}", "(#{specs.map(&:version).join(",")})"] unless specs.empty?
       end
-      if (exe = caller.last.split(":").first) && exe =~ %r{(exe|bin)/bundler?\z}
+      if (exe = caller.last.split(":").first)&.match? %r{(exe|bin)/bundler?\z}
         shebang = File.read(exe).lines.first
         shebang.sub!(/^#!\s*/, "")
         unless shebang.start_with?(Gem.ruby, "/usr/bin/env ruby")
diff --git a/lib/bundler/environment_preserver.rb b/lib/bundler/environment_preserver.rb
index 0f08e049d8..57013f5d50 100644
--- a/lib/bundler/environment_preserver.rb
+++ b/lib/bundler/environment_preserver.rb
@@ -2,11 +2,12 @@
 
 module Bundler
   class EnvironmentPreserver
-    INTENTIONALLY_NIL = "BUNDLER_ENVIRONMENT_PRESERVER_INTENTIONALLY_NIL".freeze
+    INTENTIONALLY_NIL = "BUNDLER_ENVIRONMENT_PRESERVER_INTENTIONALLY_NIL"
     BUNDLER_KEYS = %w[
       BUNDLE_BIN_PATH
       BUNDLE_GEMFILE
       BUNDLER_VERSION
+      BUNDLER_SETUP
       GEM_HOME
       GEM_PATH
       MANPATH
@@ -15,7 +16,7 @@ module Bundler
       RUBYLIB
       RUBYOPT
     ].map(&:freeze).freeze
-    BUNDLER_PREFIX = "BUNDLER_ORIG_".freeze
+    BUNDLER_PREFIX = "BUNDLER_ORIG_"
 
     def self.from_env
       new(env_to_hash(ENV), BUNDLER_KEYS)
diff --git a/lib/bundler/errors.rb b/lib/bundler/errors.rb
index 9ad7460e58..5839fc6a73 100644
--- a/lib/bundler/errors.rb
+++ b/lib/bundler/errors.rb
@@ -21,16 +21,7 @@ module Bundler
   class InstallError < BundlerError; status_code(5); end
 
   # Internal error, should be rescued
-  class VersionConflict < BundlerError
-    attr_reader :conflicts
-
-    def initialize(conflicts, msg = nil)
-      super(msg)
-      @conflicts = conflicts
-    end
-
-    status_code(6)
-  end
+  class SolveFailure < BundlerError; status_code(6); end
 
   class GemNotFound < BundlerError; status_code(7); end
   class InstallHookError < BundlerError; status_code(8); end
@@ -41,19 +32,20 @@ module Bundler
   class GemspecError < BundlerError; status_code(14); end
   class InvalidOption < BundlerError; status_code(15); end
   class ProductionError < BundlerError; status_code(16); end
+
   class HTTPError < BundlerError
     status_code(17)
     def filter_uri(uri)
       URICredentialsFilter.credential_filtered_uri(uri)
     end
   end
+
   class RubyVersionMismatch < BundlerError; status_code(18); end
   class SecurityError < BundlerError; status_code(19); end
   class LockfileError < BundlerError; status_code(20); end
   class CyclicDependencyError < BundlerError; status_code(21); end
   class GemfileLockNotFound < BundlerError; status_code(22); end
   class PluginError < BundlerError; status_code(29); end
-  class SudoNotPermittedError < BundlerError; status_code(30); end
   class ThreadCreationError < BundlerError; status_code(33); end
   class APIResponseMismatchError < BundlerError; status_code(34); end
   class APIResponseInvalidDependenciesError < BundlerError; status_code(35); end
@@ -79,10 +71,6 @@ module Bundler
       case @permission_type
       when :create
         "executable permissions for all parent directories and write permissions for `#{parent_folder}`"
-      when :delete
-        permissions = "executable permissions for all parent directories and write permissions for `#{parent_folder}`"
-        permissions += ", and the same thing for all subdirectories inside #{@path}" if File.directory?(@path)
-        permissions
       else
         "#{@permission_type} permissions for that path"
       end
@@ -172,4 +160,16 @@ module Bundler
 
     status_code(32)
   end
+
+  class DirectoryRemovalError < BundlerError
+    def initialize(orig_exception, msg)
+      full_message = "#{msg}.\n" \
+                     "The underlying error was #{orig_exception.class}: #{orig_exception.message}, with backtrace:\n" \
+                     "  #{orig_exception.backtrace.join("\n  ")}\n\n" \
+                     "Bundler Error Backtrace:"
+      super(full_message)
+    end
+
+    status_code(36)
+  end
 end
diff --git a/lib/bundler/feature_flag.rb b/lib/bundler/feature_flag.rb
index e441b941c2..ab2189f7f0 100644
--- a/lib/bundler/feature_flag.rb
+++ b/lib/bundler/feature_flag.rb
@@ -37,9 +37,7 @@ module Bundler
     settings_flag(:plugins) { @bundler_version >= Gem::Version.new("1.14") }
     settings_flag(:print_only_version_number) { bundler_3_mode? }
     settings_flag(:setup_makes_kernel_gem_public) { !bundler_3_mode? }
-    settings_flag(:suppress_install_using_messages) { bundler_3_mode? }
     settings_flag(:update_requires_all_flag) { bundler_4_mode? }
-    settings_flag(:use_gem_version_promoter_for_major_updates) { bundler_3_mode? }
 
     settings_option(:default_cli_command) { bundler_3_mode? ? :cli_help : :install }
 
diff --git a/lib/bundler/fetcher.rb b/lib/bundler/fetcher.rb
index 6fe047568f..2119799f68 100644
--- a/lib/bundler/fetcher.rb
+++ b/lib/bundler/fetcher.rb
@@ -20,6 +20,7 @@ module Bundler
     class TooManyRequestsError < HTTPError; end
     # This error is raised if the API returns a 413 (only printed in verbose)
     class FallbackError < HTTPError; end
+
     # This is the error raised if OpenSSL fails the cert verification
     class CertificateFailureError < HTTPError
       def initialize(remote_uri)
@@ -28,20 +29,18 @@ module Bundler
           " is a chance you are experiencing a man-in-the-middle attack, but" \
           " most likely your system doesn't have the CA certificates needed" \
           " for verification. For information about OpenSSL certificates, see" \
-          " https://railsapps.github.io/openssl-certificate-verify-failed.html." \
-          " To connect without using SSL, edit your Gemfile" \
-          " sources and change 'https' to 'http'."
+          " https://railsapps.github.io/openssl-certificate-verify-failed.html."
       end
     end
+
     # This is the error raised when a source is HTTPS and OpenSSL didn't load
     class SSLError < HTTPError
       def initialize(msg = nil)
         super msg || "Could not load OpenSSL.\n" \
-            "You must recompile Ruby with OpenSSL support or change the sources in your " \
-            "Gemfile from 'https' to 'http'. Instructions for compiling with OpenSSL " \
-            "using RVM are available at rvm.io/packages/openssl."
+            "You must recompile Ruby with OpenSSL support."
       end
     end
+
     # This error is raised if HTTP authentication is required, but not provided.
     class AuthenticationRequiredError < HTTPError
       def initialize(remote_uri)
@@ -52,6 +51,7 @@ module Bundler
           "or by storing the credentials in the `#{Settings.key_for(remote_uri)}` environment variable"
       end
     end
+
     # This error is raised if HTTP authentication is provided, but incorrect.
     class BadAuthenticationError < HTTPError
       def initialize(remote_uri)
@@ -61,6 +61,16 @@ module Bundler
       end
     end
 
+    # This error is raised if HTTP authentication is correct, but lacks
+    # necessary permissions.
+    class AuthenticationForbiddenError < HTTPError
+      def initialize(remote_uri)
+        remote_uri = filter_uri(remote_uri)
+        super "Access token could not be authenticated for #{remote_uri}.\n" \
+          "Make sure it's valid and has the necessary scopes configured."
+      end
+    end
+
     # Exceptions classes that should bypass retry attempts. If your password didn't work the
     # first time, it's not going to the third time.
     NET_ERRORS = [:HTTPBadGateway, :HTTPBadRequest, :HTTPFailedDependency,
@@ -70,7 +80,7 @@ module Bundler
                   :HTTPRequestURITooLong, :HTTPUnauthorized, :HTTPUnprocessableEntity,
                   :HTTPUnsupportedMediaType, :HTTPVersionNotSupported].freeze
     FAIL_ERRORS = begin
-      fail_errors = [AuthenticationRequiredError, BadAuthenticationError, FallbackError]
+      fail_errors = [AuthenticationRequiredError, BadAuthenticationError, AuthenticationForbiddenError, FallbackError]
       fail_errors << Gem::Requirement::BadRequirementError
       fail_errors.concat(NET_ERRORS.map {|e| Net.const_get(e) })
     end.freeze
@@ -102,11 +112,11 @@ module Bundler
       uri = Bundler::URI.parse("#{remote_uri}#{Gem::MARSHAL_SPEC_DIR}#{spec_file_name}.rz")
       if uri.scheme == "file"
         path = Bundler.rubygems.correct_for_windows_path(uri.path)
-        Bundler.load_marshal Bundler.rubygems.inflate(Gem.read_binary(path))
+        Bundler.safe_load_marshal Bundler.rubygems.inflate(Gem.read_binary(path))
       elsif cached_spec_path = gemspec_cached_path(spec_file_name)
         Bundler.load_gemspec(cached_spec_path)
       else
-        Bundler.load_marshal Bundler.rubygems.inflate(downloader.fetch(uri).body)
+        Bundler.safe_load_marshal Bundler.rubygems.inflate(downloader.fetch(uri).body)
       end
     rescue MarshalError
       raise HTTPError, "Gemspec #{spec} contained invalid data.\n" \
@@ -236,8 +246,8 @@ module Bundler
     def connection
       @connection ||= begin
         needs_ssl = remote_uri.scheme == "https" ||
-          Bundler.settings[:ssl_verify_mode] ||
-          Bundler.settings[:ssl_client_cert]
+                    Bundler.settings[:ssl_verify_mode] ||
+                    Bundler.settings[:ssl_client_cert]
         raise SSLError if needs_ssl && !defined?(OpenSSL::SSL)
 
         con = PersistentHTTP.new :name => "bundler", :proxy => :ENV
@@ -252,8 +262,8 @@ module Bundler
         end
 
         ssl_client_cert = Bundler.settings[:ssl_client_cert] ||
-          (Gem.configuration.ssl_client_cert if
-            Gem.configuration.respond_to?(:ssl_client_cert))
+                          (Gem.configuration.ssl_client_cert if
+                            Gem.configuration.respond_to?(:ssl_client_cert))
         if ssl_client_cert
           pem = File.read(ssl_client_cert)
           con.cert = OpenSSL::X509::Certificate.new(pem)
@@ -284,8 +294,8 @@ module Bundler
     def bundler_cert_store
       store = OpenSSL::X509::Store.new
       ssl_ca_cert = Bundler.settings[:ssl_ca_cert] ||
-        (Gem.configuration.ssl_ca_cert if
-          Gem.configuration.respond_to?(:ssl_ca_cert))
+                    (Gem.configuration.ssl_ca_cert if
+                      Gem.configuration.respond_to?(:ssl_ca_cert))
       if ssl_ca_cert
         if File.directory? ssl_ca_cert
           store.add_path ssl_ca_cert
diff --git a/lib/bundler/fetcher/base.rb b/lib/bundler/fetcher/base.rb
index 16cc98273a..62cc75add8 100644
--- a/lib/bundler/fetcher/base.rb
+++ b/lib/bundler/fetcher/base.rb
@@ -19,14 +19,12 @@ module Bundler
       end
 
       def fetch_uri
-        @fetch_uri ||= begin
-          if remote_uri.host == "rubygems.org"
-            uri = remote_uri.dup
-            uri.host = "index.rubygems.org"
-            uri
-          else
-            remote_uri
-          end
+        @fetch_uri ||= if remote_uri.host == "rubygems.org"
+          uri = remote_uri.dup
+          uri.host = "index.rubygems.org"
+          uri
+        else
+          remote_uri
         end
       end
 
diff --git a/lib/bundler/fetcher/compact_index.rb b/lib/bundler/fetcher/compact_index.rb
index b23176588f..8d30dec471 100644
--- a/lib/bundler/fetcher/compact_index.rb
+++ b/lib/bundler/fetcher/compact_index.rb
@@ -12,17 +12,15 @@ module Bundler
         method = instance_method(method_name)
         undef_method(method_name)
         define_method(method_name) do |*args, &blk|
-          begin
-            method.bind(self).call(*args, &blk)
-          rescue NetworkDownError, CompactIndexClient::Updater::MisMatchedChecksumError => e
-            raise HTTPError, e.message
-          rescue AuthenticationRequiredError
-            # Fail since we got a 401 from the server.
-            raise
-          rescue HTTPError => e
-            Bundler.ui.trace(e)
-            nil
-          end
+          method.bind(self).call(*args, &blk)
+        rescue NetworkDownError, CompactIndexClient::Updater::MisMatchedChecksumError => e
+          raise HTTPError, e.message
+        rescue AuthenticationRequiredError, BadAuthenticationError
+          # Fail since we got a 401 from the server.
+          raise
+        rescue HTTPError => e
+          Bundler.ui.trace(e)
+          nil
         end
       end
 
@@ -42,7 +40,7 @@ module Bundler
           deps = begin
                    parallel_compact_index_client.dependencies(remaining_gems)
                  rescue TooManyRequestsError
-                   @bundle_worker.stop if @bundle_worker
+                   @bundle_worker&.stop
                    @bundle_worker = nil # reset it.  Not sure if necessary
                    serial_compact_index_client.dependencies(remaining_gems)
                  end
@@ -51,7 +49,7 @@ module Bundler
           complete_gems.concat(deps.map(&:first)).uniq!
           remaining_gems = next_gems - complete_gems
         end
-        @bundle_worker.stop if @bundle_worker
+        @bundle_worker&.stop
         @bundle_worker = nil # reset it.  Not sure if necessary
 
         gem_info
diff --git a/lib/bundler/fetcher/dependency.rb b/lib/bundler/fetcher/dependency.rb
index c52c32fb5b..18b606abb6 100644
--- a/lib/bundler/fetcher/dependency.rb
+++ b/lib/bundler/fetcher/dependency.rb
@@ -34,14 +34,10 @@ module Bundler
 
         returned_gems = spec_list.map(&:first).uniq
         specs(deps_list, full_dependency_list + returned_gems, spec_list + last_spec_list)
-      rescue MarshalError
+      rescue MarshalError, HTTPError, GemspecError
         Bundler.ui.info "" unless Bundler.ui.debug? # new line now that the dots are over
         Bundler.ui.debug "could not fetch from the dependency API, trying the full index"
         nil
-      rescue HTTPError, GemspecError
-        Bundler.ui.info "" unless Bundler.ui.debug? # new line now that the dots are over
-        Bundler.ui.debug "could not fetch from the dependency API\nit's suggested to retry using the full index via `bundle install --full-index`"
-        nil
       end
 
       def dependency_specs(gem_names)
@@ -55,7 +51,7 @@ module Bundler
         gem_list = []
         gem_names.each_slice(Source::Rubygems::API_REQUEST_SIZE) do |names|
           marshalled_deps = downloader.fetch(dependency_api_uri(names)).body
-          gem_list.concat(Bundler.load_marshal(marshalled_deps))
+          gem_list.concat(Bundler.safe_load_marshal(marshalled_deps))
         end
         gem_list
       end
diff --git a/lib/bundler/fetcher/downloader.rb b/lib/bundler/fetcher/downloader.rb
index f2aad3a500..3062899e0e 100644
--- a/lib/bundler/fetcher/downloader.rb
+++ b/lib/bundler/fetcher/downloader.rb
@@ -41,6 +41,8 @@ module Bundler
         when Net::HTTPUnauthorized
           raise BadAuthenticationError, uri.host if uri.userinfo
           raise AuthenticationRequiredError, uri.host
+        when Net::HTTPForbidden
+          raise AuthenticationForbiddenError, uri.host
         when Net::HTTPNotFound
           raise FallbackError, "Net::HTTPNotFound: #{filtered_uri}"
         else
@@ -61,14 +63,11 @@ module Bundler
           req.basic_auth(user, password)
         end
         connection.request(uri, req)
-      rescue NoMethodError => e
-        raise unless ["undefined method", "use_ssl="].all? {|snippet| e.message.include? snippet }
-        raise LoadError.new("cannot load such file -- openssl")
       rescue OpenSSL::SSL::SSLError
         raise CertificateFailureError.new(uri)
       rescue *HTTP_ERRORS => e
         Bundler.ui.trace e
-        if e.is_a?(SocketError) || e.message =~ /host down:/
+        if e.is_a?(SocketError) || e.message.to_s.include?("host down:")
           raise NetworkDownError, "Could not reach host #{uri.host}. Check your network " \
             "connection and try again."
         else
@@ -80,7 +79,7 @@ module Bundler
       private
 
       def validate_uri_scheme!(uri)
-        return if uri.scheme =~ /\Ahttps?\z/
+        return if /\Ahttps?\z/.match?(uri.scheme)
         raise InvalidOption,
           "The request uri `#{uri}` has an invalid scheme (`#{uri.scheme}`). " \
           "Did you mean `http` or `https`?"
diff --git a/lib/bundler/fetcher/index.rb b/lib/bundler/fetcher/index.rb
index 6bb9fcc193..c623647f01 100644
--- a/lib/bundler/fetcher/index.rb
+++ b/lib/bundler/fetcher/index.rb
@@ -15,8 +15,7 @@ module Bundler
           raise BadAuthenticationError, remote_uri if remote_uri.userinfo
           raise AuthenticationRequiredError, remote_uri
         when /403/
-          raise BadAuthenticationError, remote_uri if remote_uri.userinfo
-          raise AuthenticationRequiredError, remote_uri
+          raise AuthenticationForbiddenError, remote_uri
         else
           raise HTTPError, "Could not fetch specs from #{display_uri} due to underlying error <#{e.message}>"
         end
diff --git a/lib/bundler/force_platform.rb b/lib/bundler/force_platform.rb
new file mode 100644
index 0000000000..249a24ecd1
--- /dev/null
+++ b/lib/bundler/force_platform.rb
@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+module Bundler
+  module ForcePlatform
+    private
+
+    # The `:force_ruby_platform` value used by dependencies for resolution, and
+    # by locked specifications for materialization is `false` by default, except
+    # for TruffleRuby. TruffleRuby generally needs to force the RUBY platform
+    # variant unless the name is explicitly allowlisted.
+
+    def default_force_ruby_platform
+      return false unless RUBY_ENGINE == "truffleruby"
+
+      !Gem::Platform::REUSE_AS_BINARY_ON_TRUFFLERUBY.include?(name)
+    end
+  end
+end
diff --git a/lib/bundler/friendly_errors.rb b/lib/bundler/friendly_errors.rb
index cc615db60c..39afe8a071 100644
--- a/lib/bundler/friendly_errors.rb
+++ b/lib/bundler/friendly_errors.rb
@@ -29,13 +29,13 @@ module Bundler
         Bundler.ui.error error.message
         Bundler.ui.trace error.orig_exception
       when BundlerError
-        Bundler.ui.error error.message, :wrap => true
-        Bundler.ui.trace error
+        if Bundler.ui.debug?
+          Bundler.ui.trace error
+        else
+          Bundler.ui.error error.message, :wrap => true
+        end
       when Thor::Error
         Bundler.ui.error error.message
-      when LoadError
-        raise error unless error.message =~ /cannot load such file -- openssl|openssl.so|libcrypto.so/
-        Bundler.ui.error "\nCould not load OpenSSL. #{error.class}: #{error}\n#{error.backtrace.join("\n  ")}"
       when Interrupt
         Bundler.ui.error "\nQuitting..."
         Bundler.ui.trace error
@@ -65,8 +65,7 @@ module Bundler
         --- ERROR REPORT TEMPLATE -------------------------------------------------------
 
         ```
-        #{e.class}: #{e.message}
-          #{e.backtrace && e.backtrace.join("\n          ").chomp}
+        #{exception_message(e)}
         ```
 
         #{Bundler::Env.report}
@@ -85,6 +84,21 @@ module Bundler
       EOS
     end
 
+    def exception_message(error)
+      message = serialized_exception_for(error)
+      cause = error.cause
+      return message unless cause
+
+      message + serialized_exception_for(cause)
+    end
+
+    def serialized_exception_for(e)
+      <<-EOS.gsub(/^ {8}/, "")
+        #{e.class}: #{e.message}
+          #{e.backtrace&.join("\n          ")&.chomp}
+      EOS
+    end
+
     def issues_url(exception)
       message = exception.message.lines.first.tr(":", " ").chomp
       message = message.split("-").first if exception.is_a?(Errno)
diff --git a/lib/bundler/gem_helper.rb b/lib/bundler/gem_helper.rb
index 0bbd2d9b75..dcf759cded 100644
--- a/lib/bundler/gem_helper.rb
+++ b/lib/bundler/gem_helper.rb
@@ -21,7 +21,7 @@ module Bundler
 
       def gemspec(&block)
         gemspec = instance.gemspec
-        block.call(gemspec) if block
+        block&.call(gemspec)
         gemspec
       end
     end
@@ -152,8 +152,7 @@ module Bundler
 
     def gem_push_host
       env_rubygems_host = ENV["RUBYGEMS_HOST"]
-      env_rubygems_host = nil if
-        env_rubygems_host && env_rubygems_host.empty?
+      env_rubygems_host = nil if env_rubygems_host&.empty?
 
       allowed_push_host || env_rubygems_host || "rubygems.org"
     end
@@ -218,7 +217,7 @@ module Bundler
       SharedHelpers.chdir(base) do
         outbuf = IO.popen(cmd, :err => [:child, :out], &:read)
         status = $?
-        block.call(outbuf) if status.success? && block
+        block&.call(outbuf) if status.success?
         [outbuf, status]
       end
     end
diff --git a/lib/bundler/gem_helpers.rb b/lib/bundler/gem_helpers.rb
index b271b8d229..2e6d788f9c 100644
--- a/lib/bundler/gem_helpers.rb
+++ b/lib/bundler/gem_helpers.rb
@@ -10,6 +10,7 @@ module Bundler
       [Gem::Platform.new("universal-mingw32"), Gem::Platform.new("universal-mingw32")],
       [Gem::Platform.new("x64-mingw32"), Gem::Platform.new("x64-mingw32")],
       [Gem::Platform.new("x86_64-mingw32"), Gem::Platform.new("x64-mingw32")],
+      [Gem::Platform.new("x64-mingw-ucrt"), Gem::Platform.new("x64-mingw-ucrt")],
       [Gem::Platform.new("mingw32"), Gem::Platform.new("x86-mingw32")],
     ].freeze
 
@@ -42,15 +43,21 @@ module Bundler
 
     def select_best_platform_match(specs, platform)
       matching = specs.select {|spec| spec.match_platform(platform) }
+
+      sort_best_platform_match(matching, platform)
+    end
+    module_function :select_best_platform_match
+
+    def sort_best_platform_match(matching, platform)
       exact = matching.select {|spec| spec.platform == platform }
       return exact if exact.any?
 
       sorted_matching = matching.sort_by {|spec| platform_specificity_match(spec.platform, platform) }
       exemplary_spec = sorted_matching.first
 
-      sorted_matching.take_while{|spec| same_specificity(platform, spec, exemplary_spec) && same_deps(spec, exemplary_spec) }
+      sorted_matching.take_while {|spec| same_specificity(platform, spec, exemplary_spec) && same_deps(spec, exemplary_spec) }
     end
-    module_function :select_best_platform_match
+    module_function :sort_best_platform_match
 
     class PlatformMatch
       def self.specificity_score(spec_platform, user_platform)
diff --git a/lib/bundler/gem_version_promoter.rb b/lib/bundler/gem_version_promoter.rb
index 3cce3f2139..d281f46eeb 100644
--- a/lib/bundler/gem_version_promoter.rb
+++ b/lib/bundler/gem_version_promoter.rb
@@ -7,14 +7,13 @@ module Bundler
   # available dependency versions as found in its index, before returning it to
   # to the resolution engine to select the best version.
   class GemVersionPromoter
-    DEBUG = ENV["BUNDLER_DEBUG_RESOLVER"] || ENV["DEBUG_RESOLVER"]
-
-    attr_reader :level, :locked_specs, :unlock_gems
+    attr_reader :level
+    attr_accessor :pre
 
     # By default, strict is false, meaning every available version of a gem
     # is returned from sort_versions. The order gives preference to the
     # requested level (:patch, :minor, :major) but in complicated requirement
-    # cases some gems will by necessity by promoted past the requested level,
+    # cases some gems will by necessity be promoted past the requested level,
     # or even reverted to older versions.
     #
     # If strict is set to true, the results from sort_versions will be
@@ -24,24 +23,13 @@ module Bundler
     # existing in the referenced source.
     attr_accessor :strict
 
-    attr_accessor :prerelease_specified
-
-    # Given a list of locked_specs and a list of gems to unlock creates a
-    # GemVersionPromoter instance.
+    # Creates a GemVersionPromoter instance.
     #
-    # @param locked_specs [SpecSet] All current locked specs. Unlike Definition
-    #   where this list is empty if all gems are being updated, this should
-    #   always be populated for all gems so this class can properly function.
-    # @param unlock_gems [String] List of gem names being unlocked. If empty,
-    #   all gems will be considered unlocked.
     # @return [GemVersionPromoter]
-    def initialize(locked_specs = SpecSet.new([]), unlock_gems = [])
+    def initialize
       @level = :major
       @strict = false
-      @locked_specs = locked_specs
-      @unlock_gems = unlock_gems
-      @sort_versions = {}
-      @prerelease_specified = {}
+      @pre = false
     end
 
     # @param value [Symbol] One of three Symbols: :major, :minor or :patch.
@@ -55,37 +43,19 @@ module Bundler
       @level = v
     end
 
-    # Given a Dependency and an Array of SpecGroups of available versions for a
-    # gem, this method will return the Array of SpecGroups sorted (and possibly
-    # truncated if strict is true) in an order to give preference to the current
-    # level (:major, :minor or :patch) when resolution is deciding what versions
-    # best resolve all dependencies in the bundle.
-    # @param dep [Dependency] The Dependency of the gem.
-    # @param spec_groups [SpecGroup] An array of SpecGroups for the same gem
-    #    named in the @dep param.
-    # @return [SpecGroup] A new instance of the SpecGroup Array sorted and
+    # Given a Resolver::Package and an Array of Specifications of available
+    # versions for a gem, this method will return the Array of Specifications
+    # sorted (and possibly truncated if strict is true) in an order to give
+    # preference to the current level (:major, :minor or :patch) when resolution
+    # is deciding what versions best resolve all dependencies in the bundle.
+    # @param package [Resolver::Package] The package being resolved.
+    # @param specs [Specification] An array of Specifications for the package.
+    # @return [Specification] A new instance of the Specification Array sorted and
     #    possibly filtered.
-    def sort_versions(dep, spec_groups)
-      before_result = "before sort_versions: #{debug_format_result(dep, spec_groups).inspect}" if DEBUG
-
-      @sort_versions[dep] ||= begin
-        gem_name = dep.name
+    def sort_versions(package, specs)
+      specs = filter_dep_specs(specs, package) if strict
 
-        # An Array per version returned, different entries for different platforms.
-        # We only need the version here so it's ok to hard code this to the first instance.
-        locked_spec = locked_specs[gem_name].first
-
-        if strict
-          filter_dep_specs(spec_groups, locked_spec)
-        else
-          sort_dep_specs(spec_groups, locked_spec)
-        end.tap do |specs|
-          if DEBUG
-            puts before_result
-            puts " after sort_versions: #{debug_format_result(dep, specs).inspect}"
-          end
-        end
-      end
+      sort_dep_specs(specs, package)
     end
 
     # @return [bool] Convenience method for testing value of level variable.
@@ -98,80 +68,72 @@ module Bundler
       level == :minor
     end
 
+    # @return [bool] Convenience method for testing value of pre variable.
+    def pre?
+      pre == true
+    end
+
     private
 
-    def filter_dep_specs(spec_groups, locked_spec)
-      res = spec_groups.select do |spec_group|
-        if locked_spec && !major?
-          gsv = spec_group.version
-          lsv = locked_spec.version
+    def filter_dep_specs(specs, package)
+      locked_version = package.locked_version
+      return specs if locked_version.nil? || major?
 
-          must_match = minor? ? [0] : [0, 1]
+      specs.select do |spec|
+        gsv = spec.version
 
-          matches = must_match.map {|idx| gsv.segments[idx] == lsv.segments[idx] }
-          matches.uniq == [true] ? (gsv >= lsv) : false
-        else
-          true
-        end
-      end
+        must_match = minor? ? [0] : [0, 1]
 
-      sort_dep_specs(res, locked_spec)
+        all_match = must_match.all? {|idx| gsv.segments[idx] == locked_version.segments[idx] }
+        all_match && gsv >= locked_version
+      end
     end
 
-    def sort_dep_specs(spec_groups, locked_spec)
-      return spec_groups unless locked_spec
-      @gem_name = locked_spec.name
-      @locked_version = locked_spec.version
-
-      result = spec_groups.sort do |a, b|
-        @a_ver = a.version
-        @b_ver = b.version
+    def sort_dep_specs(specs, package)
+      locked_version = package.locked_version
 
-        unless @prerelease_specified[@gem_name]
-          a_pre = @a_ver.prerelease?
-          b_pre = @b_ver.prerelease?
+      result = specs.sort do |a, b|
+        unless package.prerelease_specified? || pre?
+          a_pre = a.prerelease?
+          b_pre = b.prerelease?
 
           next -1 if a_pre && !b_pre
           next  1 if b_pre && !a_pre
         end
 
         if major?
-          @a_ver <=> @b_ver
-        elsif either_version_older_than_locked
-          @a_ver <=> @b_ver
-        elsif segments_do_not_match(:major)
-          @b_ver <=> @a_ver
-        elsif !minor? && segments_do_not_match(:minor)
-          @b_ver <=> @a_ver
+          a <=> b
+        elsif either_version_older_than_locked?(a, b, locked_version)
+          a <=> b
+        elsif segments_do_not_match?(a, b, :major)
+          b <=> a
+        elsif !minor? && segments_do_not_match?(a, b, :minor)
+          b <=> a
         else
-          @a_ver <=> @b_ver
+          a <=> b
         end
       end
-      post_sort(result)
+      post_sort(result, package.unlock?, locked_version)
     end
 
-    def either_version_older_than_locked
-      @a_ver < @locked_version || @b_ver < @locked_version
+    def either_version_older_than_locked?(a, b, locked_version)
+      locked_version && (a.version < locked_version || b.version < locked_version)
     end
 
-    def segments_do_not_match(level)
+    def segments_do_not_match?(a, b, level)
       index = [:major, :minor].index(level)
-      @a_ver.segments[index] != @b_ver.segments[index]
-    end
-
-    def unlocking_gem?
-      unlock_gems.empty? || unlock_gems.include?(@gem_name)
+      a.segments[index] != b.segments[index]
     end
 
     # Specific version moves can't always reliably be done during sorting
     # as not all elements are compared against each other.
-    def post_sort(result)
+    def post_sort(result, unlock, locked_version)
       # default :major behavior in Bundler does not do this
       return result if major?
-      if unlocking_gem?
+      if unlock || locked_version.nil?
         result
       else
-        move_version_to_end(result, @locked_version)
+        move_version_to_end(result, locked_version)
       end
     end
 
@@ -179,12 +141,5 @@ module Bundler
       move, keep = result.partition {|s| s.version.to_s == version.to_s }
       keep.concat(move)
     end
-
-    def debug_format_result(dep, spec_groups)
-      a = [dep.to_s,
-           spec_groups.map {|sg| [sg.version, sg.dependencies_for_activated_platforms.map {|dp| [dp.name, dp.requirement.to_s] }] }]
-      last_map = a.last.map {|sg_data| [sg_data.first.version, sg_data.last.map {|aa| aa.join(" ") }] }
-      [a.first, last_map, level, strict ? :strict : :not_strict]
-    end
   end
 end
diff --git a/lib/bundler/graph.rb b/lib/bundler/graph.rb
index 8f52e2f0f0..3c008e63e3 100644
--- a/lib/bundler/graph.rb
+++ b/lib/bundler/graph.rb
@@ -114,10 +114,10 @@ module Bundler
         @groups.each do |group|
           g.add_nodes(
             group, {
-              :style     => "filled",
+              :style => "filled",
               :fillcolor => "#B9B9D5",
-              :shape     => "box3d",
-              :fontsize  => 16,
+              :shape => "box3d",
+              :fontsize => 16,
             }.merge(@node_options[group])
           )
         end
diff --git a/lib/bundler/index.rb b/lib/bundler/index.rb
index 8930fca6d0..b8c599f63a 100644
--- a/lib/bundler/index.rb
+++ b/lib/bundler/index.rb
@@ -13,8 +13,8 @@ module Bundler
     attr_reader :specs, :all_specs, :sources
     protected :specs, :all_specs
 
-    RUBY = "ruby".freeze
-    NULL = "\0".freeze
+    RUBY = "ruby"
+    NULL = "\0"
 
     def initialize
       @sources = []
@@ -56,45 +56,21 @@ module Bundler
 
     # Search this index's specs, and any source indexes that this index knows
     # about, returning all of the results.
-    def search(query, base = nil)
-      sort_specs(unsorted_search(query, base))
-    end
-
-    def unsorted_search(query, base)
-      results = local_search(query, base)
-
-      seen = results.map(&:full_name).uniq unless @sources.empty?
+    def search(query)
+      results = local_search(query)
+      return results unless @sources.any?
 
       @sources.each do |source|
-        source.unsorted_search(query, base).each do |spec|
-          next if seen.include?(spec.full_name)
-
-          seen << spec.full_name
-          results << spec
-        end
-      end
-
-      results
-    end
-    protected :unsorted_search
-
-    def self.sort_specs(specs)
-      specs.sort_by do |s|
-        platform_string = s.platform.to_s
-        [s.version, platform_string == RUBY ? NULL : platform_string]
+        results.concat(source.search(query))
       end
+      results.uniq(&:full_name)
     end
 
-    def sort_specs(specs)
-      self.class.sort_specs(specs)
-    end
-
-    def local_search(query, base = nil)
+    def local_search(query)
       case query
       when Gem::Specification, RemoteSpecification, LazySpecification, EndpointSpecification then search_by_spec(query)
       when String then specs_by_name(query)
-      when Gem::Dependency then search_by_dependency(query, base)
-      when DepProxy then search_by_dependency(query.dep, base)
+      when Array then specs_by_name_and_version(*query)
       else
         raise "You can't search for a #{query.inspect}."
       end
@@ -181,26 +157,12 @@ module Bundler
 
     private
 
-    def specs_by_name(name)
-      @specs[name].values
+    def specs_by_name_and_version(name, version)
+      specs_by_name(name).select {|spec| spec.version == version }
     end
 
-    def search_by_dependency(dependency, base = nil)
-      @cache[base || false] ||= {}
-      @cache[base || false][dependency] ||= begin
-        specs = specs_by_name(dependency.name)
-        specs += base if base
-        found = specs.select do |spec|
-          next true if spec.source.is_a?(Source::Gemspec)
-          if base # allow all platforms when searching from a lockfile
-            dependency.matches_spec?(spec)
-          else
-            dependency.matches_spec?(spec) && Gem::Platform.match_spec?(spec)
-          end
-        end
-
-        found
-      end
+    def specs_by_name(name)
+      @specs[name].values
     end
 
     EMPTY_SEARCH = [].freeze
diff --git a/lib/bundler/injector.rb b/lib/bundler/injector.rb
index 42f837a919..cb644a7f69 100644
--- a/lib/bundler/injector.rb
+++ b/lib/bundler/injector.rb
@@ -2,7 +2,7 @@
 
 module Bundler
   class Injector
-    INJECTED_GEMS = "injected gems".freeze
+    INJECTED_GEMS = "injected gems"
 
     def self.inject(new_deps, options = {})
       injector = new(new_deps, options)
@@ -70,8 +70,12 @@ module Bundler
 
         show_warning("No gems were removed from the gemfile.") if deps.empty?
 
-        deps.each {|dep| Bundler.ui.confirm "#{SharedHelpers.pretty_dependency(dep, false)} was removed." }
+        deps.each {|dep| Bundler.ui.confirm "#{SharedHelpers.pretty_dependency(dep)} was removed." }
       end
+
+      # Invalidate the cached Bundler.definition.
+      # This prevents e.g. `bundle remove ...` from using outdated information.
+      Bundler.reset_paths!
     end
 
     private
@@ -111,13 +115,14 @@ module Bundler
         end
 
         source = ", :source => \"#{d.source}\"" unless d.source.nil?
+        path = ", :path => \"#{d.path}\"" unless d.path.nil?
         git = ", :git => \"#{d.git}\"" unless d.git.nil?
         github = ", :github => \"#{d.github}\"" unless d.github.nil?
         branch = ", :branch => \"#{d.branch}\"" unless d.branch.nil?
         ref = ", :ref => \"#{d.ref}\"" unless d.ref.nil?
         require_path = ", :require => #{convert_autorequire(d.autorequire)}" unless d.autorequire.nil?
 
-        %(gem #{name}#{requirement}#{group}#{source}#{git}#{github}#{branch}#{ref}#{require_path})
+        %(gem #{name}#{requirement}#{group}#{source}#{path}#{git}#{github}#{branch}#{ref}#{require_path})
       end.join("\n")
     end
 
@@ -230,7 +235,7 @@ module Bundler
 
         gemfile.each_with_index do |line, index|
           next unless !line.nil? && line.strip.start_with?(block_name)
-          if gemfile[index + 1] =~ /^\s*end\s*$/
+          if /^\s*end\s*$/.match?(gemfile[index + 1])
             gemfile[index] = nil
             gemfile[index + 1] = nil
           end
diff --git a/lib/bundler/inline.rb b/lib/bundler/inline.rb
index a718418fce..5c184f67a1 100644
--- a/lib/bundler/inline.rb
+++ b/lib/bundler/inline.rb
@@ -31,20 +31,16 @@
 #
 def gemfile(install = false, options = {}, &gemfile)
   require_relative "../bundler"
+  Bundler.reset!
 
   opts = options.dup
   ui = opts.delete(:ui) { Bundler::UI::Shell.new }
-  ui.level = "silent" if opts.delete(:quiet)
+  ui.level = "silent" if opts.delete(:quiet) || !install
+  Bundler.ui = ui
   raise ArgumentError, "Unknown options: #{opts.keys.join(", ")}" unless opts.empty?
 
-  begin
-    old_root = Bundler.method(:root)
-    bundler_module = class << Bundler; self; end
-    bundler_module.send(:remove_method, :root)
-    def Bundler.root
-      Bundler::SharedHelpers.pwd.expand_path
-    end
-    old_gemfile = ENV["BUNDLE_GEMFILE"]
+  Bundler.with_unbundled_env do
+    Bundler.instance_variable_set(:@bundle_path, Pathname.new(Gem.dir))
     Bundler::SharedHelpers.set_env "BUNDLE_GEMFILE", "Gemfile"
 
     Bundler::Plugin.gemfile_install(&gemfile) if Bundler.feature_flag.plugins?
@@ -57,9 +53,8 @@ def gemfile(install = false, options = {}, &gemfile)
       def definition.lock(*); end
       definition.validate_runtime!
 
-      Bundler.ui = install ? ui : Bundler::UI::Silent.new
       if install || definition.missing_specs?
-        Bundler.settings.temporary(:inline => true) do
+        Bundler.settings.temporary(:inline => true, :no_install => false) do
           installer = Bundler::Installer.install(Bundler.root, definition, :system => true)
           installer.post_install_messages.each do |name, message|
             Bundler.ui.info "Post-install message from #{name}:\n#{message}"
@@ -70,16 +65,9 @@ def gemfile(install = false, options = {}, &gemfile)
       runtime = Bundler::Runtime.new(nil, definition)
       runtime.setup.require
     end
-  ensure
-    if bundler_module
-      bundler_module.send(:remove_method, :root)
-      bundler_module.send(:define_method, :root, old_root)
-    end
+  end
 
-    if old_gemfile
-      ENV["BUNDLE_GEMFILE"] = old_gemfile
-    else
-      ENV["BUNDLE_GEMFILE"] = ""
-    end
+  if ENV["BUNDLE_GEMFILE"].nil?
+    ENV["BUNDLE_GEMFILE"] = ""
   end
 end
diff --git a/lib/bundler/installer.rb b/lib/bundler/installer.rb
index 61bf1e06d4..59b6a6ad22 100644
--- a/lib/bundler/installer.rb
+++ b/lib/bundler/installer.rb
@@ -13,7 +13,7 @@ module Bundler
       Installer.ambiguous_gems = []
     end
 
-    attr_reader :post_install_messages
+    attr_reader :post_install_messages, :definition
 
     # Begins the installation process for Bundler.
     # For more information see the #run method on this class.
@@ -66,7 +66,7 @@ module Bundler
     # require paths and save them in a `setup.rb` file. See `bundle standalone --help` for more
     # information.
     def run(options)
-      create_bundle_path
+      Bundler.create_bundle_path
 
       ProcessLock.lock do
         if Bundler.frozen_bundle?
@@ -90,7 +90,7 @@ module Bundler
 
         Gem::Specification.reset # invalidate gem specification cache so that installed gems are immediately available
 
-        lock unless Bundler.frozen_bundle?
+        lock
         Standalone.new(options[:standalone], @definition).generate if options[:standalone]
       end
     end
@@ -119,7 +119,7 @@ module Bundler
       relative_gemfile_path = relative_gemfile_path
       ruby_command = Thor::Util.ruby_command
       ruby_command = ruby_command
-      template_path = File.expand_path("../templates/Executable", __FILE__)
+      template_path = File.expand_path("templates/Executable", __dir__)
       if spec.name == "bundler"
         template_path += ".bundler"
         spec.executables = %(bundle)
@@ -136,11 +136,7 @@ module Bundler
 
         mode = Gem.win_platform? ? "wb:UTF-8" : "w"
         require "erb"
-        content = if RUBY_VERSION >= "2.6"
-          ERB.new(template, :trim_mode => "-").result(binding)
-        else
-          ERB.new(template, nil, "-").result(binding)
-        end
+        content = ERB.new(template, :trim_mode => "-").result(binding)
 
         File.write(binstub_path, content, :mode => mode, :perm => 0o777 & ~File.umask)
         if Gem.win_platform? || options[:all_platforms]
@@ -172,7 +168,7 @@ module Bundler
       end
       standalone_path = Bundler.root.join(path).relative_path_from(bin_path)
       standalone_path = standalone_path
-      template = File.read(File.expand_path("../templates/Executable.standalone", __FILE__))
+      template = File.read(File.expand_path("templates/Executable.standalone", __dir__))
       ruby_command = Thor::Util.ruby_command
       ruby_command = ruby_command
 
@@ -183,11 +179,7 @@ module Bundler
 
         mode = Gem.win_platform? ? "wb:UTF-8" : "w"
         require "erb"
-        content = if RUBY_VERSION >= "2.6"
-          ERB.new(template, :trim_mode => "-").result(binding)
-        else
-          ERB.new(template, nil, "-").result(binding)
-        end
+        content = ERB.new(template, :trim_mode => "-").result(binding)
 
         File.write("#{bin_path}/#{executable}", content, :mode => mode, :perm => 0o755)
         if Gem.win_platform? || options[:all_platforms]
@@ -226,31 +218,24 @@ module Bundler
 
       requested_path_gems = @definition.requested_specs.select {|s| s.source.is_a?(Source::Path) }
       path_plugin_files = requested_path_gems.map do |spec|
-        begin
-          Bundler.rubygems.spec_matches_for_glob(spec, "rubygems_plugin#{Bundler.rubygems.suffix_pattern}")
-        rescue TypeError
-          error_message = "#{spec.name} #{spec.version} has an invalid gemspec"
-          raise Gem::InvalidSpecificationException, error_message
-        end
+        Bundler.rubygems.spec_matches_for_glob(spec, "rubygems_plugin#{Bundler.rubygems.suffix_pattern}")
+      rescue TypeError
+        error_message = "#{spec.name} #{spec.version} has an invalid gemspec"
+        raise Gem::InvalidSpecificationException, error_message
       end.flatten
       Bundler.rubygems.load_plugin_files(path_plugin_files)
       Bundler.rubygems.load_env_plugins
     end
 
     def ensure_specs_are_compatible!
-      system_ruby = Bundler::RubyVersion.system
-      rubygems_version = Bundler.rubygems.version
       @definition.specs.each do |spec|
-        if required_ruby_version = spec.required_ruby_version
-          unless required_ruby_version.satisfied_by?(system_ruby.gem_version)
-            raise InstallError, "#{spec.full_name} requires ruby version #{required_ruby_version}, " \
-              "which is incompatible with the current version, #{system_ruby}"
-          end
+        unless spec.matches_current_ruby?
+          raise InstallError, "#{spec.full_name} requires ruby version #{spec.required_ruby_version}, " \
+            "which is incompatible with the current version, #{Gem.ruby_version}"
         end
-        next unless required_rubygems_version = spec.required_rubygems_version
-        unless required_rubygems_version.satisfied_by?(rubygems_version)
-          raise InstallError, "#{spec.full_name} requires rubygems version #{required_rubygems_version}, " \
-            "which is incompatible with the current version, #{rubygems_version}"
+        unless spec.matches_current_rubygems?
+          raise InstallError, "#{spec.full_name} requires rubygems version #{spec.required_rubygems_version}, " \
+            "which is incompatible with the current version, #{Gem.rubygems_version}"
         end
       end
     end
@@ -262,22 +247,16 @@ module Bundler
       end
     end
 
-    def create_bundle_path
-      SharedHelpers.filesystem_access(Bundler.bundle_path.to_s) do |p|
-        Bundler.mkdir_p(p)
-      end unless Bundler.bundle_path.exist?
-    rescue Errno::EEXIST
-      raise PathError, "Could not install to path `#{Bundler.bundle_path}` " \
-        "because a file already exists at that path. Either remove or rename the file so the directory can be created."
-    end
-
     # returns whether or not a re-resolve was needed
     def resolve_if_needed(options)
+      @definition.resolution_mode = options
+
       if !@definition.unlocking? && !options["force"] && !Bundler.settings[:inline] && Bundler.default_lockfile.file?
         return false if @definition.nothing_changed? && !@definition.missing_specs?
       end
 
-      options["local"] ? @definition.resolve_with_cache! : @definition.resolve_remotely!
+      @definition.setup_sources_for_resolve
+
       true
     end
 
diff --git a/lib/bundler/installer/gem_installer.rb b/lib/bundler/installer/gem_installer.rb
index 13a1356f56..9a013eea4d 100644
--- a/lib/bundler/installer/gem_installer.rb
+++ b/lib/bundler/installer/gem_installer.rb
@@ -51,7 +51,20 @@ module Bundler
     end
 
     def install
-      spec.source.install(spec, :force => force, :ensure_builtin_gems_cached => standalone, :build_args => Array(spec_settings))
+      spec.source.install(
+        spec,
+        :force => force,
+        :ensure_builtin_gems_cached => standalone,
+        :build_args => Array(spec_settings),
+        :previous_spec => previous_spec,
+      )
+    end
+
+    def previous_spec
+      locked_gems = installer.definition.locked_gems
+      return unless locked_gems
+
+      locked_gems.specs.find {|s| s.name == spec.name }
     end
 
     def out_of_space_message
diff --git a/lib/bundler/installer/parallel_installer.rb b/lib/bundler/installer/parallel_installer.rb
index 5b6680e5e1..83a381f592 100644
--- a/lib/bundler/installer/parallel_installer.rb
+++ b/lib/bundler/installer/parallel_installer.rb
@@ -53,10 +53,6 @@ module Bundler
         @dependencies ||= all_dependencies.reject {|dep| ignorable_dependency? dep }
       end
 
-      def missing_lockfile_dependencies(all_spec_names)
-        dependencies.reject {|dep| all_spec_names.include? dep.name }
-      end
-
       # Represents all dependencies
       def all_dependencies
         @spec.dependencies
@@ -84,8 +80,6 @@ module Bundler
     end
 
     def call
-      check_for_corrupt_lockfile
-
       if @rake
         do_install(@rake, 0)
         Gem::Specification.reset
@@ -102,7 +96,7 @@ module Bundler
       handle_error if failed_specs.any?
       @specs
     ensure
-      worker_pool && worker_pool.stop
+      worker_pool&.stop
     end
 
     def check_for_unmet_dependencies
@@ -116,43 +110,19 @@ module Bundler
 
       warning = []
       warning << "Your lockfile doesn't include a valid resolution."
-      warning << "You can fix this by regenerating your lockfile or trying to manually editing the bad locked gems to a version that satisfies all dependencies."
+      warning << "You can fix this by regenerating your lockfile or manually editing the bad locked gems to a version that satisfies all dependencies."
       warning << "The unmet dependencies are:"
 
       unmet_dependencies.each do |spec, unmet_spec_dependencies|
         unmet_spec_dependencies.each do |unmet_spec_dependency|
-          warning << "* #{unmet_spec_dependency}, depended upon #{spec.full_name}, unsatisfied by #{@specs.find {|s| s.name == unmet_spec_dependency.name && !unmet_spec_dependency.matches_spec?(s.spec) }.full_name}"
+          found = @specs.find {|s| s.name == unmet_spec_dependency.name && !unmet_spec_dependency.matches_spec?(s.spec) }
+          warning << "* #{unmet_spec_dependency}, dependency of #{spec.full_name}, unsatisfied by #{found.full_name}"
         end
       end
 
       Bundler.ui.warn(warning.join("\n"))
     end
 
-    def check_for_corrupt_lockfile
-      missing_dependencies = @specs.map do |s|
-        [
-          s,
-          s.missing_lockfile_dependencies(@specs.map(&:name)),
-        ]
-      end.reject {|a| a.last.empty? }
-      return if missing_dependencies.empty?
-
-      warning = []
-      warning << "Your lockfile was created by an old Bundler that left some things out."
-      if @size != 1
-        warning << "Because of the missing DEPENDENCIES, we can only install gems one at a time, instead of installing #{@size} at a time."
-        @size = 1
-      end
-      warning << "You can fix this by adding the missing gems to your Gemfile, running bundle install, and then removing the gems from your Gemfile."
-      warning << "The missing gems are:"
-
-      missing_dependencies.each do |spec, missing|
-        warning << "* #{missing.map(&:name).join(", ")} depended upon by #{spec.name}"
-      end
-
-      Bundler.ui.warn(warning.join("\n"))
-    end
-
     private
 
     def failed_specs
diff --git a/lib/bundler/installer/standalone.rb b/lib/bundler/installer/standalone.rb
index e8494b4bcd..2a8c9a432d 100644
--- a/lib/bundler/installer/standalone.rb
+++ b/lib/bundler/installer/standalone.rb
@@ -12,6 +12,7 @@ module Bundler
       end
       File.open File.join(bundler_path, "setup.rb"), "w" do |file|
         file.puts "require 'rbconfig'"
+        file.puts define_path_helpers
         file.puts reverse_rubygems_kernel_mixin
         paths.each do |path|
           if Pathname.new(path).absolute?
@@ -29,23 +30,29 @@ module Bundler
       @specs.map do |spec|
         next if spec.name == "bundler"
         Array(spec.require_paths).map do |path|
-          gem_path(path, spec).sub(version_dir, '#{RUBY_ENGINE}/#{RbConfig::CONFIG["ruby_version"]}')
+          gem_path(path, spec).
+            sub(version_dir, '#{RUBY_ENGINE}/#{Gem.ruby_api_version}').
+            sub(extensions_dir, 'extensions/\k<platform>/#{Gem.extension_api_version}')
           # This is a static string intentionally. It's interpolated at a later time.
         end
       end.flatten.compact
     end
 
     def version_dir
-      "#{RUBY_ENGINE}/#{RbConfig::CONFIG["ruby_version"]}"
+      "#{RUBY_ENGINE}/#{Gem.ruby_api_version}"
+    end
+
+    def extensions_dir
+      %r{extensions/(?<platform>[^/]+)/#{Regexp.escape(Gem.extension_api_version)}}
     end
 
     def bundler_path
-      Bundler.root.join(Bundler.settings[:path], "bundler")
+      Bundler.root.join(Bundler.settings[:path].to_s, "bundler")
     end
 
     def gem_path(path, spec)
       full_path = Pathname.new(path).absolute? ? path : File.join(spec.full_gem_path, path)
-      if spec.source.instance_of?(Source::Path)
+      if spec.source.instance_of?(Source::Path) && spec.source.path.absolute?
         full_path
       else
         Pathname.new(full_path).relative_path_from(Bundler.root.join(bundler_path)).to_s
@@ -55,15 +62,39 @@ module Bundler
       raise Gem::InvalidSpecificationException.new(error_message)
     end
 
+    def define_path_helpers
+      <<~'END'
+        unless defined?(Gem)
+          module Gem
+            def self.ruby_api_version
+              RbConfig::CONFIG["ruby_version"]
+            end
+
+            def self.extension_api_version
+              if 'no' == RbConfig::CONFIG['ENABLE_SHARED']
+                "#{ruby_api_version}-static"
+              else
+                ruby_api_version
+              end
+            end
+          end
+        end
+      END
+    end
+
     def reverse_rubygems_kernel_mixin
       <<~END
-      kernel = (class << ::Kernel; self; end)
-      [kernel, ::Kernel].each do |k|
-        if k.private_method_defined?(:gem_original_require)
-          private_require = k.private_method_defined?(:require)
-          k.send(:remove_method, :require)
-          k.send(:define_method, :require, k.instance_method(:gem_original_require))
-          k.send(:private, :require) if private_require
+      if Gem.respond_to?(:discover_gems_on_require=)
+        Gem.discover_gems_on_require = false
+      else
+        kernel = (class << ::Kernel; self; end)
+        [kernel, ::Kernel].each do |k|
+          if k.private_method_defined?(:gem_original_require)
+            private_require = k.private_method_defined?(:require)
+            k.send(:remove_method, :require)
+            k.send(:define_method, :require, k.instance_method(:gem_original_require))
+            k.send(:private, :require) if private_require
+          end
         end
       end
       END
diff --git a/lib/bundler/lazy_specification.rb b/lib/bundler/lazy_specification.rb
index fd7c8defdc..c9b161dc0e 100644
--- a/lib/bundler/lazy_specification.rb
+++ b/lib/bundler/lazy_specification.rb
@@ -1,13 +1,14 @@
 # frozen_string_literal: true
 
-require_relative "match_platform"
+require_relative "force_platform"
 
 module Bundler
   class LazySpecification
     include MatchPlatform
+    include ForcePlatform
 
     attr_reader :name, :version, :dependencies, :platform
-    attr_accessor :source, :remote
+    attr_accessor :source, :remote, :force_ruby_platform
 
     def initialize(name, version, platform, source = nil)
       @name          = name
@@ -15,11 +16,11 @@ module Bundler
       @dependencies  = []
       @platform      = platform || Gem::Platform::RUBY
       @source        = source
-      @specification = nil
+      @force_ruby_platform = default_force_ruby_platform
     end
 
     def full_name
-      if platform == Gem::Platform::RUBY || platform.nil?
+      @full_name ||= if platform == Gem::Platform::RUBY
         "#{@name}-#{@version}"
       else
         "#{@name}-#{@version}-#{platform}"
@@ -27,15 +28,15 @@ module Bundler
     end
 
     def ==(other)
-      identifier == other.identifier
+      full_name == other.full_name
     end
 
     def eql?(other)
-      identifier.eql?(other.identifier)
+      full_name.eql?(other.full_name)
     end
 
     def hash
-      identifier.hash
+      full_name.hash
     end
 
     ##
@@ -61,7 +62,7 @@ module Bundler
     def to_lock
       out = String.new
 
-      if platform == Gem::Platform::RUBY || platform.nil?
+      if platform == Gem::Platform::RUBY
         out << "    #{name} (#{version})\n"
       else
         out << "    #{name} (#{version}-#{platform})\n"
@@ -75,76 +76,74 @@ module Bundler
       out
     end
 
-    def __materialize__
-      @specification = if source.is_a?(Source::Gemspec) && source.gemspec.name == name
-        source.gemspec.tap {|s| s.source = source }
+    def materialize_for_installation
+      source.local!
+
+      matching_specs = source.specs.search(use_exact_resolved_specifications? ? self : [name, version])
+      return self if matching_specs.empty?
+
+      candidates = if use_exact_resolved_specifications?
+        matching_specs
       else
-        search_object = if source.is_a?(Source::Path)
-          Dependency.new(name, version)
-        else
-          ruby_platform_materializes_to_ruby_platform? ? self : Dependency.new(name, version)
-        end
-        platform_object = Gem::Platform.new(platform)
-        candidates = source.specs.search(search_object)
-        same_platform_candidates = candidates.select do |spec|
-          MatchPlatform.platforms_match?(spec.platform, platform_object)
-        end
-        installable_candidates = same_platform_candidates.select do |spec|
-          spec.is_a?(StubSpecification) ||
-            (spec.required_ruby_version.satisfied_by?(Gem.ruby_version) &&
-              spec.required_rubygems_version.satisfied_by?(Gem.rubygems_version))
+        target_platform = ruby_platform_materializes_to_ruby_platform? ? platform : local_platform
+
+        installable_candidates = GemHelpers.select_best_platform_match(matching_specs, target_platform)
+
+        specification = __materialize__(installable_candidates, :fallback_to_non_installable => false)
+        return specification unless specification.nil?
+
+        if target_platform != platform
+          installable_candidates = GemHelpers.select_best_platform_match(matching_specs, platform)
         end
-        search = installable_candidates.last
-        search.dependencies = dependencies if search && (search.is_a?(RemoteSpecification) || search.is_a?(EndpointSpecification))
-        search
+
+        installable_candidates
       end
+
+      __materialize__(candidates)
     end
 
-    def respond_to?(*args)
-      super || @specification ? @specification.respond_to?(*args) : nil
+    # If in frozen mode, we fallback to a non-installable candidate because by
+    # doing this we avoid re-resolving and potentially end up changing the
+    # lock file, which is not allowed. In that case, we will give a proper error
+    # about the mismatch higher up the stack, right before trying to install the
+    # bad gem.
+    def __materialize__(candidates, fallback_to_non_installable: Bundler.frozen_bundle?)
+      search = candidates.reverse.find do |spec|
+        spec.is_a?(StubSpecification) ||
+          (spec.matches_current_ruby? &&
+            spec.matches_current_rubygems?)
+      end
+      if search.nil? && fallback_to_non_installable
+        search = candidates.last
+      else
+        search.dependencies = dependencies if search && search.full_name == full_name && (search.is_a?(RemoteSpecification) || search.is_a?(EndpointSpecification))
+      end
+      search
     end
 
     def to_s
-      @__to_s ||= if platform == Gem::Platform::RUBY || platform.nil?
+      @to_s ||= if platform == Gem::Platform::RUBY
         "#{name} (#{version})"
       else
         "#{name} (#{version}-#{platform})"
       end
     end
 
-    def identifier
-      @__identifier ||= [name, version, platform_string]
-    end
-
     def git_version
       return unless source.is_a?(Bundler::Source::Git)
       " #{source.revision[0..6]}"
     end
 
-    protected
-
-    def platform_string
-      platform_string = platform.to_s
-      platform_string == Index::RUBY ? Index::NULL : platform_string
-    end
-
     private
 
-    def to_ary
-      nil
-    end
-
-    def method_missing(method, *args, &blk)
-      raise "LazySpecification has not been materialized yet (calling :#{method} #{args.inspect})" unless @specification
-
-      return super unless respond_to?(method)
-
-      @specification.send(method, *args, &blk)
+    def use_exact_resolved_specifications?
+      @use_exact_resolved_specifications ||= !source.is_a?(Source::Path) && ruby_platform_materializes_to_ruby_platform?
     end
 
     #
     # For backwards compatibility with existing lockfiles, if the most specific
-    # locked platform is RUBY, we keep the previous behaviour of resolving the
+    # locked platform is not a specific platform like x86_64-linux or
+    # universal-java-11, then we keep the previous behaviour of resolving the
     # best platform variant at materiliazation time. For previous bundler
     # versions (before 2.2.0) this was always the case (except when the lockfile
     # only included non-ruby platforms), but we're also keeping this behaviour
@@ -152,7 +151,9 @@ module Bundler
     # explicitly add a more specific platform.
     #
     def ruby_platform_materializes_to_ruby_platform?
-      !Bundler.most_specific_locked_platform?(Gem::Platform::RUBY) || Bundler.settings[:force_ruby_platform]
+      generic_platform = generic_local_platform == Gem::Platform::JAVA ? Gem::Platform::JAVA : Gem::Platform::RUBY
+
+      !Bundler.most_specific_locked_platform?(generic_platform) || force_ruby_platform || Bundler.settings[:force_ruby_platform]
     end
   end
 end
diff --git a/lib/bundler/lockfile_generator.rb b/lib/bundler/lockfile_generator.rb
index 0578a93fdc..f7ba51b3e6 100644
--- a/lib/bundler/lockfile_generator.rb
+++ b/lib/bundler/lockfile_generator.rb
@@ -45,7 +45,7 @@ module Bundler
       # gems with the same name, but different platform
       # are ordered consistently
       specs.sort_by(&:full_name).each do |spec|
-        next if spec.name == "bundler".freeze
+        next if spec.name == "bundler"
         out << spec.to_lock
       end
     end
@@ -60,7 +60,7 @@ module Bundler
       handled = []
       definition.dependencies.sort_by(&:to_s).each do |dep|
         next if handled.include?(dep.name)
-        out << dep.to_lock
+        out << dep.to_lock << "\n"
         handled << dep.name
       end
     end
@@ -71,7 +71,7 @@ module Bundler
     end
 
     def add_bundled_with
-      add_section("BUNDLED WITH", Bundler::VERSION)
+      add_section("BUNDLED WITH", definition.bundler_version_to_lock.to_s)
     end
 
     def add_section(name, value)
diff --git a/lib/bundler/lockfile_parser.rb b/lib/bundler/lockfile_parser.rb
index e074cbfc33..7360a36752 100644
--- a/lib/bundler/lockfile_parser.rb
+++ b/lib/bundler/lockfile_parser.rb
@@ -4,15 +4,15 @@ module Bundler
   class LockfileParser
     attr_reader :sources, :dependencies, :specs, :platforms, :bundler_version, :ruby_version
 
-    BUNDLED      = "BUNDLED WITH".freeze
-    DEPENDENCIES = "DEPENDENCIES".freeze
-    PLATFORMS    = "PLATFORMS".freeze
-    RUBY         = "RUBY VERSION".freeze
-    GIT          = "GIT".freeze
-    GEM          = "GEM".freeze
-    PATH         = "PATH".freeze
-    PLUGIN       = "PLUGIN SOURCE".freeze
-    SPECS        = "  specs:".freeze
+    BUNDLED      = "BUNDLED WITH"
+    DEPENDENCIES = "DEPENDENCIES"
+    PLATFORMS    = "PLATFORMS"
+    RUBY         = "RUBY VERSION"
+    GIT          = "GIT"
+    GEM          = "GEM"
+    PATH         = "PATH"
+    PLUGIN       = "PLUGIN SOURCE"
+    SPECS        = "  specs:"
     OPTIONS      = /^  ([a-z]+): (.*)$/i.freeze
     SOURCE       = [GIT, GEM, PATH, PLUGIN].freeze
 
@@ -26,6 +26,7 @@ module Bundler
     KNOWN_SECTIONS = SECTIONS_BY_VERSION_INTRODUCED.values.flatten.freeze
 
     ENVIRONMENT_VERSION_SECTIONS = [BUNDLED, RUBY].freeze
+    deprecate_constant(:ENVIRONMENT_VERSION_SECTIONS)
 
     def self.sections_in_lockfile(lockfile_contents)
       lockfile_contents.scan(/^\w[\w ]*$/).uniq
@@ -63,7 +64,7 @@ module Bundler
       @state        = nil
       @specs        = {}
 
-      if lockfile.match(/<<<<<<<|=======|>>>>>>>|\|\|\|\|\|\|\|/)
+      if lockfile.match?(/<<<<<<<|=======|>>>>>>>|\|\|\|\|\|\|\|/)
         raise LockfileError, "Your #{Bundler.default_lockfile.relative_path_from(SharedHelpers.pwd)} contains merge conflicts.\n" \
           "Run `git checkout HEAD -- #{Bundler.default_lockfile.relative_path_from(SharedHelpers.pwd)}` first to get a clean lock."
       end
@@ -80,25 +81,29 @@ module Bundler
           @state = :ruby
         elsif line == BUNDLED
           @state = :bundled_with
-        elsif line =~ /^[^\s]/
+        elsif /^[^\s]/.match?(line)
           @state = nil
         elsif @state
           send("parse_#{@state}", line)
         end
       end
-      @specs = @specs.values.sort_by(&:identifier)
+      @specs = @specs.values.sort_by(&:full_name)
     rescue ArgumentError => e
       Bundler.ui.debug(e)
       raise LockfileError, "Your lockfile is unreadable. Run `rm #{Bundler.default_lockfile.relative_path_from(SharedHelpers.pwd)}` " \
         "and then `bundle install` to generate a new lockfile."
     end
 
+    def may_include_redundant_platform_specific_gems?
+      bundler_version.nil? || bundler_version < Gem::Version.new("1.16.2")
+    end
+
     private
 
     TYPES = {
-      GIT    => Bundler::Source::Git,
-      GEM    => Bundler::Source::Rubygems,
-      PATH   => Bundler::Source::Path,
+      GIT => Bundler::Source::Git,
+      GEM => Bundler::Source::Rubygems,
+      PATH => Bundler::Source::Path,
       PLUGIN => Bundler::Plugin,
     }.freeze
 
@@ -195,7 +200,7 @@ module Bundler
         @current_spec.source = @current_source
         @current_source.add_dependency_names(name)
 
-        @specs[@current_spec.identifier] = @current_spec
+        @specs[@current_spec.full_name] = @current_spec
       elsif spaces.size == 6
         version = version.split(",").map(&:strip) if version
         dep = Gem::Dependency.new(name, version)
diff --git a/lib/bundler/man/bundle-add.1 b/lib/bundler/man/bundle-add.1
index 7ad5443cae..8549855b0d 100644
--- a/lib/bundler/man/bundle-add.1
+++ b/lib/bundler/man/bundle-add.1
@@ -1,13 +1,13 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-ADD" "1" "March 2022" "" ""
+.TH "BUNDLE\-ADD" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-add\fR \- Add gem to the Gemfile and run bundle install
 .
 .SH "SYNOPSIS"
-\fBbundle add\fR \fIGEM_NAME\fR [\-\-group=GROUP] [\-\-version=VERSION] [\-\-source=SOURCE] [\-\-git=GIT] [\-\-github=GITHUB] [\-\-branch=BRANCH] [\-\-ref=REF] [\-\-skip\-install] [\-\-strict] [\-\-optimistic]
+\fBbundle add\fR \fIGEM_NAME\fR [\-\-group=GROUP] [\-\-version=VERSION] [\-\-source=SOURCE] [\-\-path=PATH] [\-\-git=GIT] [\-\-github=GITHUB] [\-\-branch=BRANCH] [\-\-ref=REF] [\-\-skip\-install] [\-\-strict] [\-\-optimistic]
 .
 .SH "DESCRIPTION"
 Adds the named gem to the Gemfile and run \fBbundle install\fR\. \fBbundle install\fR can be avoided by using the flag \fB\-\-skip\-install\fR\.
@@ -41,10 +41,18 @@ Specify version requirements(s) for the added gem\.
 Specify the group(s) for the added gem\. Multiple groups should be separated by commas\.
 .
 .TP
-\fB\-\-source\fR, , \fB\-s\fR
+\fB\-\-source\fR, \fB\-s\fR
 Specify the source for the added gem\.
 .
 .TP
+\fB\-\-require\fR, \fB\-r\fR
+Adds require path to gem\. Provide false, or a path as a string\.
+.
+.TP
+\fB\-\-path\fR
+Specify the file system path for the added gem\.
+.
+.TP
 \fB\-\-git\fR
 Specify the git source for the added gem\.
 .
@@ -66,9 +74,9 @@ Adds the gem to the Gemfile but does not install it\.
 .
 .TP
 \fB\-\-optimistic\fR
-Adds optimistic declaration of version
+Adds optimistic declaration of version\.
 .
 .TP
 \fB\-\-strict\fR
-Adds strict declaration of version
+Adds strict declaration of version\.
 
diff --git a/lib/bundler/man/bundle-add.1.ronn b/lib/bundler/man/bundle-add.1.ronn
index 6547297c86..37c92e5fcd 100644
--- a/lib/bundler/man/bundle-add.1.ronn
+++ b/lib/bundler/man/bundle-add.1.ronn
@@ -3,7 +3,7 @@ bundle-add(1) -- Add gem to the Gemfile and run bundle install
 
 ## SYNOPSIS
 
-`bundle add` <GEM_NAME> [--group=GROUP] [--version=VERSION] [--source=SOURCE] [--git=GIT] [--github=GITHUB] [--branch=BRANCH] [--ref=REF] [--skip-install] [--strict] [--optimistic]
+`bundle add` <GEM_NAME> [--group=GROUP] [--version=VERSION] [--source=SOURCE] [--path=PATH] [--git=GIT] [--github=GITHUB] [--branch=BRANCH] [--ref=REF] [--skip-install] [--strict] [--optimistic]
 
 ## DESCRIPTION
 Adds the named gem to the Gemfile and run `bundle install`. `bundle install` can be avoided by using the flag `--skip-install`.
@@ -27,9 +27,15 @@ bundle add rails --group "development, test"
 * `--group`, `-g`:
   Specify the group(s) for the added gem. Multiple groups should be separated by commas.
 
-* `--source`, , `-s`:
+* `--source`, `-s`:
   Specify the source for the added gem.
 
+* `--require`, `-r`:
+  Adds require path to gem. Provide false, or a path as a string.
+
+* `--path`:
+  Specify the file system path for the added gem.
+
 * `--git`:
   Specify the git source for the added gem.
 
@@ -46,7 +52,7 @@ bundle add rails --group "development, test"
   Adds the gem to the Gemfile but does not install it.
 
 * `--optimistic`:
-  Adds optimistic declaration of version
+  Adds optimistic declaration of version.
 
 * `--strict`:
-  Adds strict declaration of version
+  Adds strict declaration of version.
diff --git a/lib/bundler/man/bundle-binstubs.1 b/lib/bundler/man/bundle-binstubs.1
index 20ad1c5cc8..40c338916a 100644
--- a/lib/bundler/man/bundle-binstubs.1
+++ b/lib/bundler/man/bundle-binstubs.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-BINSTUBS" "1" "March 2022" "" ""
+.TH "BUNDLE\-BINSTUBS" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-binstubs\fR \- Install the binstubs of the listed gems
diff --git a/lib/bundler/man/bundle-cache.1 b/lib/bundler/man/bundle-cache.1
index 7929885924..69b1e1e3dd 100644
--- a/lib/bundler/man/bundle-cache.1
+++ b/lib/bundler/man/bundle-cache.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-CACHE" "1" "March 2022" "" ""
+.TH "BUNDLE\-CACHE" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-cache\fR \- Package your needed \fB\.gem\fR files into your application
@@ -9,8 +9,11 @@
 .SH "SYNOPSIS"
 \fBbundle cache\fR
 .
+.P
+alias: \fBpackage\fR, \fBpack\fR
+.
 .SH "DESCRIPTION"
-Copy all of the \fB\.gem\fR files needed to run the application into the \fBvendor/cache\fR directory\. In the future, when running [bundle install(1)][bundle\-install], use the gems in the cache in preference to the ones on \fBrubygems\.org\fR\.
+Copy all of the \fB\.gem\fR files needed to run the application into the \fBvendor/cache\fR directory\. In the future, when running \fBbundle install(1)\fR \fIbundle\-install\.1\.html\fR, use the gems in the cache in preference to the ones on \fBrubygems\.org\fR\.
 .
 .SH "GIT AND PATH GEMS"
 The \fBbundle cache\fR command can also package \fB:git\fR and \fB:path\fR dependencies besides \.gem files\. This needs to be explicitly enabled via the \fB\-\-all\fR option\. Once used, the \fB\-\-all\fR option will be remembered\.
@@ -19,7 +22,7 @@ The \fBbundle cache\fR command can also package \fB:git\fR and \fB:path\fR depen
 When using gems that have different packages for different platforms, Bundler supports caching of gems for other platforms where the Gemfile has been resolved (i\.e\. present in the lockfile) in \fBvendor/cache\fR\. This needs to be enabled via the \fB\-\-all\-platforms\fR option\. This setting will be remembered in your local bundler configuration\.
 .
 .SH "REMOTE FETCHING"
-By default, if you run \fBbundle install(1)\fR](bundle\-install\.1\.html) after running bundle cache(1) \fIbundle\-cache\.1\.html\fR, bundler will still connect to \fBrubygems\.org\fR to check whether a platform\-specific gem exists for any of the gems in \fBvendor/cache\fR\.
+By default, if you run \fBbundle install(1)\fR \fIbundle\-install\.1\.html\fR after running bundle cache(1) \fIbundle\-cache\.1\.html\fR, bundler will still connect to \fBrubygems\.org\fR to check whether a platform\-specific gem exists for any of the gems in \fBvendor/cache\fR\.
 .
 .P
 For instance, consider this Gemfile(5):
@@ -53,3 +56,6 @@ One way to be sure that you have the right platformed versions of all your gems
 .
 .P
 By default, bundle cache(1) \fIbundle\-cache\.1\.html\fR fetches and also installs the gems to the default location\. To package the dependencies to \fBvendor/cache\fR without installing them to the local install location, you can run \fBbundle cache \-\-no\-install\fR\.
+.
+.SH "HISTORY"
+In Bundler 2\.1, \fBcache\fR took in the functionalities of \fBpackage\fR and now \fBpackage\fR and \fBpack\fR are aliases of \fBcache\fR\.
diff --git a/lib/bundler/man/bundle-cache.1.ronn b/lib/bundler/man/bundle-cache.1.ronn
index 383adb2ba3..8112c2c551 100644
--- a/lib/bundler/man/bundle-cache.1.ronn
+++ b/lib/bundler/man/bundle-cache.1.ronn
@@ -5,10 +5,12 @@ bundle-cache(1) -- Package your needed `.gem` files into your application
 
 `bundle cache`
 
+alias: `package`, `pack`
+
 ## DESCRIPTION
 
 Copy all of the `.gem` files needed to run the application into the
-`vendor/cache` directory. In the future, when running [bundle install(1)][bundle-install],
+`vendor/cache` directory. In the future, when running [`bundle install(1)`](bundle-install.1.html),
 use the gems in the cache in preference to the ones on `rubygems.org`.
 
 ## GIT AND PATH GEMS
@@ -27,7 +29,7 @@ bundler configuration.
 
 ## REMOTE FETCHING
 
-By default, if you run `bundle install(1)`](bundle-install.1.html) after running
+By default, if you run [`bundle install(1)`](bundle-install.1.html) after running
 [bundle cache(1)](bundle-cache.1.html), bundler will still connect to `rubygems.org`
 to check whether a platform-specific gem exists for any of the gems
 in `vendor/cache`.
@@ -70,3 +72,8 @@ By default, [bundle cache(1)](bundle-cache.1.html) fetches and also
 installs the gems to the default location. To package the
 dependencies to `vendor/cache` without installing them to the
 local install location, you can run `bundle cache --no-install`.
+
+## HISTORY
+
+In Bundler 2.1, `cache` took in the functionalities of `package` and now
+`package` and `pack` are aliases of `cache`.
diff --git a/lib/bundler/man/bundle-check.1 b/lib/bundler/man/bundle-check.1
index b3a1a06b59..748a37e7d1 100644
--- a/lib/bundler/man/bundle-check.1
+++ b/lib/bundler/man/bundle-check.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-CHECK" "1" "March 2022" "" ""
+.TH "BUNDLE\-CHECK" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-check\fR \- Verifies if dependencies are satisfied by installed gems
diff --git a/lib/bundler/man/bundle-clean.1 b/lib/bundler/man/bundle-clean.1
index f48b453149..af8f13cd89 100644
--- a/lib/bundler/man/bundle-clean.1
+++ b/lib/bundler/man/bundle-clean.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-CLEAN" "1" "March 2022" "" ""
+.TH "BUNDLE\-CLEAN" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-clean\fR \- Cleans up unused gems in your bundler directory
@@ -20,5 +20,5 @@ Print the changes, but do not clean the unused gems\.
 .
 .TP
 \fB\-\-force\fR
-Force a clean even if \fB\-\-path\fR is not set\.
+Forces cleaning up unused gems even if Bundler is configured to use globally installed gems\. As a consequence, removes all system gems except for the ones in the current application\.
 
diff --git a/lib/bundler/man/bundle-clean.1.ronn b/lib/bundler/man/bundle-clean.1.ronn
index de23991782..dae27c21ee 100644
--- a/lib/bundler/man/bundle-clean.1.ronn
+++ b/lib/bundler/man/bundle-clean.1.ronn
@@ -15,4 +15,4 @@ useful when you have made many changes to your gem dependencies.
 * `--dry-run`:
   Print the changes, but do not clean the unused gems.
 * `--force`:
-  Force a clean even if `--path` is not set.
+  Forces cleaning up unused gems even if Bundler is configured to use globally installed gems. As a consequence, removes all system gems except for the ones in the current application.
diff --git a/lib/bundler/man/bundle-config.1 b/lib/bundler/man/bundle-config.1
index d657910e83..4442f33105 100644
--- a/lib/bundler/man/bundle-config.1
+++ b/lib/bundler/man/bundle-config.1
@@ -1,13 +1,22 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-CONFIG" "1" "March 2022" "" ""
+.TH "BUNDLE\-CONFIG" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-config\fR \- Set bundler configuration options
 .
 .SH "SYNOPSIS"
-\fBbundle config\fR [list|get|set|unset] [\fIname\fR [\fIvalue\fR]]
+\fBbundle config\fR list
+.
+.br
+\fBbundle config\fR [get] NAME
+.
+.br
+\fBbundle config\fR [set] NAME VALUE
+.
+.br
+\fBbundle config\fR unset NAME
 .
 .SH "DESCRIPTION"
 This command allows you to interact with Bundler\'s configuration system\.
@@ -30,7 +39,7 @@ Bundler default config
 .IP "" 0
 .
 .P
-Executing \fBbundle config list\fR with will print a list of all bundler configuration for the current bundle, and where that configuration was set\.
+Executing \fBbundle config list\fR will print a list of all bundler configuration for the current bundle, and where that configuration was set\.
 .
 .P
 Executing \fBbundle config get <name>\fR will print the value of that configuration setting, and where it was set\.
@@ -51,7 +60,7 @@ Executing \fBbundle config unset <name>\fR will delete the configuration in both
 Executing \fBbundle config unset \-\-global <name>\fR will delete the configuration only from the user configuration\.
 .
 .P
-Executing \fBbundle config unset \-\-local <name> <value>\fR will delete the configuration only from the local application\.
+Executing \fBbundle config unset \-\-local <name>\fR will delete the configuration only from the local application\.
 .
 .P
 Executing bundle with the \fBBUNDLE_IGNORE_CONFIG\fR environment variable set will cause it to ignore all configuration\.
@@ -74,6 +83,10 @@ Creates a directory (defaults to \fB~/bin\fR) and place any executables from the
 In deployment mode, Bundler will \'roll\-out\' the bundle for \fBproduction\fR use\. Please check carefully if you want to have this option enabled in \fBdevelopment\fR or \fBtest\fR environments\.
 .
 .TP
+\fBonly\fR
+A space\-separated list of groups to install only gems of the specified groups\.
+.
+.TP
 \fBpath\fR
 The location to install the specified gems to\. This defaults to Rubygems\' setting\. Bundler shares this location with Rubygems, \fBgem install \.\.\.\fR will have gem installed there, too\. Therefore, gems installed without a \fB\-\-path \.\.\.\fR setting will show up by calling \fBgem list\fR\. Accordingly, gems installed to other locations will not get listed\.
 .
@@ -205,6 +218,9 @@ The following is a list of all configuration keys and their purpose\. You can le
 \fBglobal_gem_cache\fR (\fBBUNDLE_GLOBAL_GEM_CACHE\fR): Whether Bundler should cache all gems globally, rather than locally to the installing Ruby installation\.
 .
 .IP "\(bu" 4
+\fBignore_funding_requests\fR (\fBBUNDLE_IGNORE_FUNDING_REQUESTS\fR): When set, no funding requests will be printed\.
+.
+.IP "\(bu" 4
 \fBignore_messages\fR (\fBBUNDLE_IGNORE_MESSAGES\fR): When set, no post install messages will be printed\. To silence a single gem, use dot notation like \fBignore_messages\.httparty true\fR\.
 .
 .IP "\(bu" 4
@@ -220,6 +236,9 @@ The following is a list of all configuration keys and their purpose\. You can le
 \fBno_prune\fR (\fBBUNDLE_NO_PRUNE\fR): Whether Bundler should leave outdated gems unpruned when caching\.
 .
 .IP "\(bu" 4
+\fBonly\fR (\fBBUNDLE_ONLY\fR): A space\-separated list of groups to install only gems of the specified groups\.
+.
+.IP "\(bu" 4
 \fBpath\fR (\fBBUNDLE_PATH\fR): The location on disk where all gems in your bundle will be located regardless of \fB$GEM_HOME\fR or \fB$GEM_PATH\fR values\. Bundle gems not found in this location will be installed by \fBbundle install\fR\. Defaults to \fBGem\.dir\fR\. When \-\-deployment is used, defaults to vendor/bundle\.
 .
 .IP "\(bu" 4
@@ -265,9 +284,6 @@ The following is a list of all configuration keys and their purpose\. You can le
 \fBssl_verify_mode\fR (\fBBUNDLE_SSL_VERIFY_MODE\fR): The SSL verification mode Bundler uses when making HTTPS requests\. Defaults to verify peer\.
 .
 .IP "\(bu" 4
-\fBsuppress_install_using_messages\fR (\fBBUNDLE_SUPPRESS_INSTALL_USING_MESSAGES\fR): Avoid printing \fBUsing \.\.\.\fR messages during installation when the version of a gem has not changed\.
-.
-.IP "\(bu" 4
 \fBsystem_bindir\fR (\fBBUNDLE_SYSTEM_BINDIR\fR): The location where RubyGems installs binstubs\. Defaults to \fBGem\.bindir\fR\.
 .
 .IP "\(bu" 4
@@ -288,7 +304,7 @@ The following is a list of all configuration keys and their purpose\. You can le
 .IP "" 0
 .
 .P
-In general, you should set these settings per\-application by using the applicable flag to the bundle install(1) \fIbundle\-install\.1\.html\fR or bundle package(1) \fIbundle\-package\.1\.html\fR command\.
+In general, you should set these settings per\-application by using the applicable flag to the bundle install(1) \fIbundle\-install\.1\.html\fR or bundle cache(1) \fIbundle\-cache\.1\.html\fR command\.
 .
 .P
 You can set them globally either via environment variables or \fBbundle config\fR, whichever is preferable for your setup\. If you use both, environment variables will take preference over global settings\.
@@ -342,13 +358,13 @@ bundle config set \-\-global mirror\.SOURCE_URL MIRROR_URL
 .IP "" 0
 .
 .P
-For example, to use a mirror of rubygems\.org hosted at rubygems\-mirror\.org:
+For example, to use a mirror of https://rubygems\.org hosted at https://example\.org:
 .
 .IP "" 4
 .
 .nf
 
-bundle config set \-\-global mirror\.http://rubygems\.org http://rubygems\-mirror\.org
+bundle config set \-\-global mirror\.https://rubygems\.org https://example\.org
 .
 .fi
 .
diff --git a/lib/bundler/man/bundle-config.1.ronn b/lib/bundler/man/bundle-config.1.ronn
index 7d1cb271a9..adc273ec62 100644
--- a/lib/bundler/man/bundle-config.1.ronn
+++ b/lib/bundler/man/bundle-config.1.ronn
@@ -3,7 +3,10 @@ bundle-config(1) -- Set bundler configuration options
 
 ## SYNOPSIS
 
-`bundle config` [list|get|set|unset] [<name> [<value>]]
+`bundle config` list<br>
+`bundle config` [get] NAME<br>
+`bundle config` [set] NAME VALUE<br>
+`bundle config` unset NAME
 
 ## DESCRIPTION
 
@@ -16,7 +19,7 @@ Bundler loads configuration settings in this order:
 3. Global config (`~/.bundle/config`)
 4. Bundler default config
 
-Executing `bundle config list` with will print a list of all bundler
+Executing `bundle config list` will print a list of all bundler
 configuration for the current bundle, and where that configuration
 was set.
 
@@ -43,8 +46,8 @@ local and global sources.
 Executing `bundle config unset --global <name>` will delete the configuration
 only from the user configuration.
 
-Executing `bundle config unset --local <name> <value>` will delete the
-configuration only from the local application.
+Executing `bundle config unset --local <name>` will delete the configuration
+only from the local application.
 
 Executing bundle with the `BUNDLE_IGNORE_CONFIG` environment variable set will
 cause it to ignore all configuration.
@@ -74,6 +77,9 @@ The options that can be configured are:
    `production` use. Please check carefully if you want to have this option
    enabled in `development` or `test` environments.
 
+* `only`:
+   A space-separated list of groups to install only gems of the specified groups.
+
 * `path`:
    The location to install the specified gems to. This defaults to Rubygems'
    setting. Bundler shares this location with Rubygems, `gem install ...` will
@@ -204,6 +210,8 @@ learn more about their operation in [bundle install(1)](bundle-install.1.html).
 * `global_gem_cache` (`BUNDLE_GLOBAL_GEM_CACHE`):
    Whether Bundler should cache all gems globally, rather than locally to the
    installing Ruby installation.
+* `ignore_funding_requests` (`BUNDLE_IGNORE_FUNDING_REQUESTS`):
+   When set, no funding requests will be printed.
 * `ignore_messages` (`BUNDLE_IGNORE_MESSAGES`):
    When set, no post install messages will be printed. To silence a single gem,
    use dot notation like `ignore_messages.httparty true`.
@@ -216,6 +224,8 @@ learn more about their operation in [bundle install(1)](bundle-install.1.html).
    Whether `bundle package` should skip installing gems.
 * `no_prune` (`BUNDLE_NO_PRUNE`):
    Whether Bundler should leave outdated gems unpruned when caching.
+* `only` (`BUNDLE_ONLY`):
+   A space-separated list of groups to install only gems of the specified groups.
 * `path` (`BUNDLE_PATH`):
    The location on disk where all gems in your bundle will be located regardless
    of `$GEM_HOME` or `$GEM_PATH` values. Bundle gems not found in this location
@@ -255,9 +265,6 @@ learn more about their operation in [bundle install(1)](bundle-install.1.html).
 * `ssl_verify_mode` (`BUNDLE_SSL_VERIFY_MODE`):
    The SSL verification mode Bundler uses when making HTTPS requests.
    Defaults to verify peer.
-* `suppress_install_using_messages` (`BUNDLE_SUPPRESS_INSTALL_USING_MESSAGES`):
-   Avoid printing `Using ...` messages during installation when the version of
-   a gem has not changed.
 * `system_bindir` (`BUNDLE_SYSTEM_BINDIR`):
    The location where RubyGems installs binstubs. Defaults to `Gem.bindir`.
 * `timeout` (`BUNDLE_TIMEOUT`):
@@ -273,7 +280,7 @@ learn more about their operation in [bundle install(1)](bundle-install.1.html).
    A `:`-separated list of groups whose gems bundler should not install.
 
 In general, you should set these settings per-application by using the applicable
-flag to the [bundle install(1)](bundle-install.1.html) or [bundle package(1)](bundle-package.1.html) command.
+flag to the [bundle install(1)](bundle-install.1.html) or [bundle cache(1)](bundle-cache.1.html) command.
 
 You can set them globally either via environment variables or `bundle config`,
 whichever is preferable for your setup. If you use both, environment variables
@@ -321,9 +328,9 @@ mirror to fetch gems.
 
     bundle config set --global mirror.SOURCE_URL MIRROR_URL
 
-For example, to use a mirror of rubygems.org hosted at rubygems-mirror.org:
+For example, to use a mirror of https://rubygems.org hosted at https://example.org:
 
-    bundle config set --global mirror.http://rubygems.org http://rubygems-mirror.org
+    bundle config set --global mirror.https://rubygems.org https://example.org
 
 Each mirror also provides a fallback timeout setting. If the mirror does not
 respond within the fallback timeout, Bundler will try to use the original
diff --git a/lib/bundler/man/bundle-console.1 b/lib/bundler/man/bundle-console.1
new file mode 100644
index 0000000000..24fff46cec
--- /dev/null
+++ b/lib/bundler/man/bundle-console.1
@@ -0,0 +1,53 @@
+.\" generated with Ronn/v0.7.3
+.\" http://github.com/rtomayko/ronn/tree/0.7.3
+.
+.TH "BUNDLE\-CONSOLE" "1" "August 2023" "" ""
+.
+.SH "NAME"
+\fBbundle\-console\fR \- Deprecated way to open an IRB session with the bundle pre\-loaded
+.
+.SH "SYNOPSIS"
+\fBbundle console\fR [GROUP]
+.
+.SH "DESCRIPTION"
+Starts an interactive Ruby console session in the context of the current bundle\.
+.
+.P
+If no \fBGROUP\fR is specified, all gems in the \fBdefault\fR group in the Gemfile(5) \fIhttps://bundler\.io/man/gemfile\.5\.html\fR are preliminarily loaded\.
+.
+.P
+If \fBGROUP\fR is specified, all gems in the given group in the Gemfile in addition to the gems in \fBdefault\fR group are loaded\. Even if the given group does not exist in the Gemfile, IRB console starts without any warning or error\.
+.
+.P
+The environment variable \fBBUNDLE_CONSOLE\fR or \fBbundle config set console\fR can be used to change the shell from the following:
+.
+.IP "\(bu" 4
+\fBirb\fR (default)
+.
+.IP "\(bu" 4
+\fBpry\fR (https://github\.com/pry/pry)
+.
+.IP "\(bu" 4
+\fBripl\fR (https://github\.com/cldwalker/ripl)
+.
+.IP "" 0
+.
+.P
+\fBbundle console\fR uses irb by default\. An alternative Pry or Ripl can be used with \fBbundle console\fR by adjusting the \fBconsole\fR Bundler setting\. Also make sure that \fBpry\fR or \fBripl\fR is in your Gemfile\.
+.
+.SH "EXAMPLE"
+.
+.nf
+
+$ bundle config set console pry
+$ bundle console
+Resolving dependencies\.\.\.
+[1] pry(main)>
+.
+.fi
+.
+.SH "NOTES"
+This command was deprecated in Bundler 2\.1 and will be removed in 3\.0\. Use \fBbin/console\fR script, which can be generated by \fBbundle gem <NAME>\fR\.
+.
+.SH "SEE ALSO"
+Gemfile(5) \fIhttps://bundler\.io/man/gemfile\.5\.html\fR
diff --git a/lib/bundler/man/bundle-console.1.ronn b/lib/bundler/man/bundle-console.1.ronn
new file mode 100644
index 0000000000..f9096d386a
--- /dev/null
+++ b/lib/bundler/man/bundle-console.1.ronn
@@ -0,0 +1,44 @@
+bundle-console(1) -- Deprecated way to open an IRB session with the bundle pre-loaded
+=====================================================================================
+
+## SYNOPSIS
+
+`bundle console` [GROUP]
+
+## DESCRIPTION
+
+Starts an interactive Ruby console session in the context of the current bundle.
+
+If no `GROUP` is specified, all gems in the `default` group in the [Gemfile(5)](https://bundler.io/man/gemfile.5.html) are
+preliminarily loaded.
+
+If `GROUP` is specified, all gems in the given group in the Gemfile in addition
+to the gems in `default` group are loaded. Even if the given group does not
+exist in the Gemfile, IRB console starts without any warning or error.
+
+The environment variable `BUNDLE_CONSOLE` or `bundle config set console` can be used to change
+the shell from the following:
+
+* `irb` (default)
+* `pry` (https://github.com/pry/pry)
+* `ripl` (https://github.com/cldwalker/ripl)
+
+`bundle console` uses irb by default. An alternative Pry or Ripl can be used with
+`bundle console` by adjusting the `console` Bundler setting. Also make sure that
+`pry` or `ripl` is in your Gemfile.
+
+## EXAMPLE
+
+    $ bundle config set console pry
+    $ bundle console
+    Resolving dependencies...
+    [1] pry(main)>
+
+## NOTES
+
+This command was deprecated in Bundler 2.1 and will be removed in 3.0.
+Use `bin/console` script, which can be generated by `bundle gem <NAME>`.
+
+## SEE ALSO
+
+[Gemfile(5)](https://bundler.io/man/gemfile.5.html)
diff --git a/lib/bundler/man/bundle-doctor.1 b/lib/bundler/man/bundle-doctor.1
index d638275a02..57da8216cb 100644
--- a/lib/bundler/man/bundle-doctor.1
+++ b/lib/bundler/man/bundle-doctor.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-DOCTOR" "1" "March 2022" "" ""
+.TH "BUNDLE\-DOCTOR" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-doctor\fR \- Checks the bundle for common problems
diff --git a/lib/bundler/man/bundle-exec.1 b/lib/bundler/man/bundle-exec.1
index 90118c1fff..852788db7a 100644
--- a/lib/bundler/man/bundle-exec.1
+++ b/lib/bundler/man/bundle-exec.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-EXEC" "1" "March 2022" "" ""
+.TH "BUNDLE\-EXEC" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-exec\fR \- Execute a command in the context of the bundle
@@ -74,13 +74,13 @@ Finally, \fBbundle exec\fR also implicitly modifies \fBGemfile\.lock\fR if the l
 By default, when attempting to \fBbundle exec\fR to a file with a ruby shebang, Bundler will \fBKernel\.load\fR that file instead of using \fBKernel\.exec\fR\. For the vast majority of cases, this is a performance improvement\. In a rare few cases, this could cause some subtle side\-effects (such as dependence on the exact contents of \fB$0\fR or \fB__FILE__\fR) and the optimization can be disabled by enabling the \fBdisable_exec_load\fR setting\.
 .
 .SS "Shelling out"
-Any Ruby code that opens a subshell (like \fBsystem\fR, backticks, or \fB%x{}\fR) will automatically use the current Bundler environment\. If you need to shell out to a Ruby command that is not part of your current bundle, use the \fBwith_clean_env\fR method with a block\. Any subshells created inside the block will be given the environment present before Bundler was activated\. For example, Homebrew commands run Ruby, but don\'t work inside a bundle:
+Any Ruby code that opens a subshell (like \fBsystem\fR, backticks, or \fB%x{}\fR) will automatically use the current Bundler environment\. If you need to shell out to a Ruby command that is not part of your current bundle, use the \fBwith_unbundled_env\fR method with a block\. Any subshells created inside the block will be given the environment present before Bundler was activated\. For example, Homebrew commands run Ruby, but don\'t work inside a bundle:
 .
 .IP "" 4
 .
 .nf
 
-Bundler\.with_clean_env do
+Bundler\.with_unbundled_env do
   `brew install wget`
 end
 .
@@ -89,13 +89,13 @@ end
 .IP "" 0
 .
 .P
-Using \fBwith_clean_env\fR is also necessary if you are shelling out to a different bundle\. Any Bundler commands run in a subshell will inherit the current Gemfile, so commands that need to run in the context of a different bundle also need to use \fBwith_clean_env\fR\.
+Using \fBwith_unbundled_env\fR is also necessary if you are shelling out to a different bundle\. Any Bundler commands run in a subshell will inherit the current Gemfile, so commands that need to run in the context of a different bundle also need to use \fBwith_unbundled_env\fR\.
 .
 .IP "" 4
 .
 .nf
 
-Bundler\.with_clean_env do
+Bundler\.with_unbundled_env do
   Dir\.chdir "/other/bundler/project" do
     `bundle exec \./script`
   end
@@ -155,7 +155,7 @@ You can find a list of all the gems containing gem plugins by running
 .
 .nf
 
-ruby \-rrubygems \-e "puts Gem\.find_files(\'rubygems_plugin\.rb\')"
+ruby \-e "puts Gem\.find_files(\'rubygems_plugin\.rb\')"
 .
 .fi
 .
diff --git a/lib/bundler/man/bundle-exec.1.ronn b/lib/bundler/man/bundle-exec.1.ronn
index dec3c7cb82..05948095e2 100644
--- a/lib/bundler/man/bundle-exec.1.ronn
+++ b/lib/bundler/man/bundle-exec.1.ronn
@@ -84,20 +84,20 @@ the `disable_exec_load` setting.
 Any Ruby code that opens a subshell (like `system`, backticks, or `%x{}`) will
 automatically use the current Bundler environment. If you need to shell out to
 a Ruby command that is not part of your current bundle, use the
-`with_clean_env` method with a block. Any subshells created inside the block
+`with_unbundled_env` method with a block. Any subshells created inside the block
 will be given the environment present before Bundler was activated. For
 example, Homebrew commands run Ruby, but don't work inside a bundle:
 
-    Bundler.with_clean_env do
+    Bundler.with_unbundled_env do
       `brew install wget`
     end
 
-Using `with_clean_env` is also necessary if you are shelling out to a different
+Using `with_unbundled_env` is also necessary if you are shelling out to a different
 bundle. Any Bundler commands run in a subshell will inherit the current
 Gemfile, so commands that need to run in the context of a different bundle also
-need to use `with_clean_env`.
+need to use `with_unbundled_env`.
 
-    Bundler.with_clean_env do
+    Bundler.with_unbundled_env do
       Dir.chdir "/other/bundler/project" do
         `bundle exec ./script`
       end
@@ -145,7 +145,7 @@ their plugins.
 You can find a list of all the gems containing gem plugins
 by running
 
-    ruby -rrubygems -e "puts Gem.find_files('rubygems_plugin.rb')"
+    ruby -e "puts Gem.find_files('rubygems_plugin.rb')"
 
 At the very least, you should remove all but the newest
 version of each gem plugin, and also remove all gem plugins
diff --git a/lib/bundler/man/bundle-gem.1 b/lib/bundler/man/bundle-gem.1
index 10681e3696..8339b727ce 100644
--- a/lib/bundler/man/bundle-gem.1
+++ b/lib/bundler/man/bundle-gem.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-GEM" "1" "March 2022" "" ""
+.TH "BUNDLE\-GEM" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-gem\fR \- Generate a project skeleton for creating a rubygem
@@ -31,41 +31,32 @@ The generated project skeleton can be customized with OPTIONS, as explained belo
 .
 .SH "OPTIONS"
 .
-.TP
-\fB\-\-exe\fR or \fB\-b\fR or \fB\-\-bin\fR
-Specify that Bundler should create a binary executable (as \fBexe/GEM_NAME\fR) in the generated rubygem project\. This binary will also be added to the \fBGEM_NAME\.gemspec\fR manifest\. This behavior is disabled by default\.
+.IP "\(bu" 4
+\fB\-\-exe\fR or \fB\-b\fR or \fB\-\-bin\fR: Specify that Bundler should create a binary executable (as \fBexe/GEM_NAME\fR) in the generated rubygem project\. This binary will also be added to the \fBGEM_NAME\.gemspec\fR manifest\. This behavior is disabled by default\.
 .
-.TP
-\fB\-\-no\-exe\fR
-Do not create a binary (overrides \fB\-\-exe\fR specified in the global config)\.
+.IP "\(bu" 4
+\fB\-\-no\-exe\fR: Do not create a binary (overrides \fB\-\-exe\fR specified in the global config)\.
 .
-.TP
-\fB\-\-coc\fR
-Add a \fBCODE_OF_CONDUCT\.md\fR file to the root of the generated project\. If this option is unspecified, an interactive prompt will be displayed and the answer will be saved in Bundler\'s global config for future \fBbundle gem\fR use\.
+.IP "\(bu" 4
+\fB\-\-coc\fR: Add a \fBCODE_OF_CONDUCT\.md\fR file to the root of the generated project\. If this option is unspecified, an interactive prompt will be displayed and the answer will be saved in Bundler\'s global config for future \fBbundle gem\fR use\.
 .
-.TP
-\fB\-\-no\-coc\fR
-Do not create a \fBCODE_OF_CONDUCT\.md\fR (overrides \fB\-\-coc\fR specified in the global config)\.
+.IP "\(bu" 4
+\fB\-\-no\-coc\fR: Do not create a \fBCODE_OF_CONDUCT\.md\fR (overrides \fB\-\-coc\fR specified in the global config)\.
 .
-.TP
-\fB\-\-ext\fR
-Add boilerplate for C extension code to the generated project\. This behavior is disabled by default\.
+.IP "\(bu" 4
+\fB\-\-ext=c\fR, \fB\-\-ext=rust\fR Add boilerplate for C or Rust (currently magnus \fIhttps://docs\.rs/magnus\fR based) extension code to the generated project\. This behavior is disabled by default\.
 .
-.TP
-\fB\-\-no\-ext\fR
-Do not add C extension code (overrides \fB\-\-ext\fR specified in the global config)\.
+.IP "\(bu" 4
+\fB\-\-no\-ext\fR: Do not add extension code (overrides \fB\-\-ext\fR specified in the global config)\.
 .
-.TP
-\fB\-\-mit\fR
-Add an MIT license to a \fBLICENSE\.txt\fR file in the root of the generated project\. Your name from the global git config is used for the copyright statement\. If this option is unspecified, an interactive prompt will be displayed and the answer will be saved in Bundler\'s global config for future \fBbundle gem\fR use\.
+.IP "\(bu" 4
+\fB\-\-mit\fR: Add an MIT license to a \fBLICENSE\.txt\fR file in the root of the generated project\. Your name from the global git config is used for the copyright statement\. If this option is unspecified, an interactive prompt will be displayed and the answer will be saved in Bundler\'s global config for future \fBbundle gem\fR use\.
 .
-.TP
-\fB\-\-no\-mit\fR
-Do not create a \fBLICENSE\.txt\fR (overrides \fB\-\-mit\fR specified in the global config)\.
+.IP "\(bu" 4
+\fB\-\-no\-mit\fR: Do not create a \fBLICENSE\.txt\fR (overrides \fB\-\-mit\fR specified in the global config)\.
 .
-.TP
-\fB\-t\fR, \fB\-\-test=minitest\fR, \fB\-\-test=rspec\fR, \fB\-\-test=test\-unit\fR
-Specify the test framework that Bundler should use when generating the project\. Acceptable values are \fBminitest\fR, \fBrspec\fR and \fBtest\-unit\fR\. The \fBGEM_NAME\.gemspec\fR will be configured and a skeleton test/spec directory will be created based on this option\. Given no option is specified:
+.IP "\(bu" 4
+\fB\-t\fR, \fB\-\-test=minitest\fR, \fB\-\-test=rspec\fR, \fB\-\-test=test\-unit\fR: Specify the test framework that Bundler should use when generating the project\. Acceptable values are \fBminitest\fR, \fBrspec\fR and \fBtest\-unit\fR\. The \fBGEM_NAME\.gemspec\fR will be configured and a skeleton test/spec directory will be created based on this option\. Given no option is specified:
 .
 .IP
 When Bundler is configured to generate tests, this defaults to Bundler\'s global config setting \fBgem\.test\fR\.
@@ -76,9 +67,8 @@ When Bundler is configured to not generate tests, an interactive prompt will be
 .IP
 When Bundler is unconfigured, an interactive prompt will be displayed and the answer will be saved in Bundler\'s global config for future \fBbundle gem\fR use\.
 .
-.TP
-\fB\-\-ci\fR, \fB\-\-ci=github\fR, \fB\-\-ci=travis\fR, \fB\-\-ci=gitlab\fR, \fB\-\-ci=circle\fR
-Specify the continuous integration service that Bundler should use when generating the project\. Acceptable values are \fBgithub\fR, \fBtravis\fR, \fBgitlab\fR and \fBcircle\fR\. A configuration file will be generated in the project directory\. Given no option is specified:
+.IP "\(bu" 4
+\fB\-\-ci\fR, \fB\-\-ci=github\fR, \fB\-\-ci=gitlab\fR, \fB\-\-ci=circle\fR: Specify the continuous integration service that Bundler should use when generating the project\. Acceptable values are \fBgithub\fR, \fBgitlab\fR and \fBcircle\fR\. A configuration file will be generated in the project directory\. Given no option is specified:
 .
 .IP
 When Bundler is configured to generate CI files, this defaults to Bundler\'s global config setting \fBgem\.ci\fR\.
@@ -89,9 +79,8 @@ When Bundler is configured to not generate CI files, an interactive prompt will
 .IP
 When Bundler is unconfigured, an interactive prompt will be displayed and the answer will be saved in Bundler\'s global config for future \fBbundle gem\fR use\.
 .
-.TP
-\fB\-\-linter\fR, \fB\-\-linter=rubocop\fR, \fB\-\-linter=standard\fR
-Specify the linter and code formatter that Bundler should add to the project\'s development dependencies\. Acceptable values are \fBrubocop\fR and \fBstandard\fR\. A configuration file will be generated in the project directory\. Given no option is specified:
+.IP "\(bu" 4
+\fB\-\-linter\fR, \fB\-\-linter=rubocop\fR, \fB\-\-linter=standard\fR: Specify the linter and code formatter that Bundler should add to the project\'s development dependencies\. Acceptable values are \fBrubocop\fR and \fBstandard\fR\. A configuration file will be generated in the project directory\. Given no option is specified:
 .
 .IP
 When Bundler is configured to add a linter, this defaults to Bundler\'s global config setting \fBgem\.linter\fR\.
@@ -102,9 +91,10 @@ When Bundler is configured not to add a linter, an interactive prompt will be di
 .IP
 When Bundler is unconfigured, an interactive prompt will be displayed and the answer will be saved in Bundler\'s global config for future \fBbundle gem\fR use\.
 .
-.TP
-\fB\-e\fR, \fB\-\-edit[=EDITOR]\fR
-Open the resulting GEM_NAME\.gemspec in EDITOR, or the default editor if not specified\. The default is \fB$BUNDLER_EDITOR\fR, \fB$VISUAL\fR, or \fB$EDITOR\fR\.
+.IP "\(bu" 4
+\fB\-e\fR, \fB\-\-edit[=EDITOR]\fR: Open the resulting GEM_NAME\.gemspec in EDITOR, or the default editor if not specified\. The default is \fB$BUNDLER_EDITOR\fR, \fB$VISUAL\fR, or \fB$EDITOR\fR\.
+.
+.IP "" 0
 .
 .SH "SEE ALSO"
 .
diff --git a/lib/bundler/man/bundle-gem.1.ronn b/lib/bundler/man/bundle-gem.1.ronn
index 61c741fb24..46fa2f179f 100644
--- a/lib/bundler/man/bundle-gem.1.ronn
+++ b/lib/bundler/man/bundle-gem.1.ronn
@@ -41,12 +41,12 @@ configuration file using the following names:
   Do not create a `CODE_OF_CONDUCT.md` (overrides `--coc` specified in the
   global config).
 
-* `--ext`:
-  Add boilerplate for C extension code to the generated project. This behavior
+* `--ext=c`, `--ext=rust`
+  Add boilerplate for C or Rust (currently [magnus](https://docs.rs/magnus) based) extension code to the generated project. This behavior
   is disabled by default.
 
 * `--no-ext`:
-  Do not add C extension code (overrides `--ext` specified in the global
+  Do not add extension code (overrides `--ext` specified in the global
   config).
 
 * `--mit`:
@@ -76,9 +76,9 @@ configuration file using the following names:
   the answer will be saved in Bundler's global config for future `bundle gem`
   use.
 
-* `--ci`, `--ci=github`, `--ci=travis`, `--ci=gitlab`, `--ci=circle`:
+* `--ci`, `--ci=github`, `--ci=gitlab`, `--ci=circle`:
   Specify the continuous integration service that Bundler should use when
-  generating the project. Acceptable values are `github`, `travis`, `gitlab`
+  generating the project. Acceptable values are `github`, `gitlab`
   and `circle`. A configuration file will be generated in the project directory.
   Given no option is specified:
 
diff --git a/lib/bundler/man/bundle-help.1 b/lib/bundler/man/bundle-help.1
new file mode 100644
index 0000000000..9787c2d49f
--- /dev/null
+++ b/lib/bundler/man/bundle-help.1
@@ -0,0 +1,13 @@
+.\" generated with Ronn/v0.7.3
+.\" http://github.com/rtomayko/ronn/tree/0.7.3
+.
+.TH "BUNDLE\-HELP" "1" "August 2023" "" ""
+.
+.SH "NAME"
+\fBbundle\-help\fR \- Displays detailed help for each subcommand
+.
+.SH "SYNOPSIS"
+\fBbundle help\fR [COMMAND]
+.
+.SH "DESCRIPTION"
+Displays detailed help for the given subcommand\. You can specify a single \fBCOMMAND\fR at the same time\. When \fBCOMMAND\fR is omitted, help for \fBhelp\fR command will be displayed\.
diff --git a/lib/bundler/man/bundle-help.1.ronn b/lib/bundler/man/bundle-help.1.ronn
new file mode 100644
index 0000000000..0e144aead7
--- /dev/null
+++ b/lib/bundler/man/bundle-help.1.ronn
@@ -0,0 +1,12 @@
+bundle-help(1) -- Displays detailed help for each subcommand
+============================================================
+
+## SYNOPSIS
+
+`bundle help` [COMMAND]
+
+## DESCRIPTION
+
+Displays detailed help for the given subcommand.
+You can specify a single `COMMAND` at the same time.
+When `COMMAND` is omitted, help for `help` command will be displayed.
diff --git a/lib/bundler/man/bundle-info.1 b/lib/bundler/man/bundle-info.1
index 57bdc6bd93..2cced71520 100644
--- a/lib/bundler/man/bundle-info.1
+++ b/lib/bundler/man/bundle-info.1
@@ -1,16 +1,16 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-INFO" "1" "March 2022" "" ""
+.TH "BUNDLE\-INFO" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-info\fR \- Show information for the given gem in your bundle
 .
 .SH "SYNOPSIS"
-\fBbundle info\fR [GEM] [\-\-path]
+\fBbundle info\fR [GEM_NAME] [\-\-path]
 .
 .SH "DESCRIPTION"
-Print the basic information about the provided GEM such as homepage, version, path and summary\.
+Given a gem name present in your bundle, print the basic information about it such as homepage, version, path and summary\.
 .
 .SH "OPTIONS"
 .
diff --git a/lib/bundler/man/bundle-info.1.ronn b/lib/bundler/man/bundle-info.1.ronn
index 47e457aa3c..cecdeb564f 100644
--- a/lib/bundler/man/bundle-info.1.ronn
+++ b/lib/bundler/man/bundle-info.1.ronn
@@ -3,13 +3,13 @@ bundle-info(1) -- Show information for the given gem in your bundle
 
 ## SYNOPSIS
 
-`bundle info` [GEM]
+`bundle info` [GEM_NAME]
               [--path]
 
 ## DESCRIPTION
 
-Print the basic information about the provided GEM such as homepage, version,
-path and summary.
+Given a gem name present in your bundle, print the basic information about it
+ such as homepage, version, path and summary.
 
 ## OPTIONS
 
diff --git a/lib/bundler/man/bundle-init.1 b/lib/bundler/man/bundle-init.1
index 1524980762..c7a9a155b5 100644
--- a/lib/bundler/man/bundle-init.1
+++ b/lib/bundler/man/bundle-init.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-INIT" "1" "March 2022" "" ""
+.TH "BUNDLE\-INIT" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-init\fR \- Generates a Gemfile into the current working directory
@@ -18,6 +18,10 @@ Init generates a default [\fBGemfile(5)\fR][Gemfile(5)] in the current working d
 \fB\-\-gemspec\fR
 Use the specified \.gemspec to create the [\fBGemfile(5)\fR][Gemfile(5)]
 .
+.TP
+\fB\-\-gemfile\fR
+Use the specified name for the gemfile instead of \fBGemfile\fR
+.
 .SH "FILES"
 Included in the default [\fBGemfile(5)\fR][Gemfile(5)] generated is the line \fB# frozen_string_literal: true\fR\. This is a magic comment supported for the first time in Ruby 2\.3\. The presence of this line results in all string literals in the file being implicitly frozen\.
 .
diff --git a/lib/bundler/man/bundle-init.1.ronn b/lib/bundler/man/bundle-init.1.ronn
index 9d3d97deea..7d3cede1f6 100644
--- a/lib/bundler/man/bundle-init.1.ronn
+++ b/lib/bundler/man/bundle-init.1.ronn
@@ -16,6 +16,8 @@ created [`Gemfile(5)`][Gemfile(5)].
 
 * `--gemspec`:
   Use the specified .gemspec to create the [`Gemfile(5)`][Gemfile(5)]
+* `--gemfile`:
+  Use the specified name for the gemfile instead of `Gemfile`
 
 ## FILES
 
diff --git a/lib/bundler/man/bundle-inject.1 b/lib/bundler/man/bundle-inject.1
index bb8123d175..9e25c29085 100644
--- a/lib/bundler/man/bundle-inject.1
+++ b/lib/bundler/man/bundle-inject.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-INJECT" "1" "March 2022" "" ""
+.TH "BUNDLE\-INJECT" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-inject\fR \- Add named gem(s) with version requirements to Gemfile
@@ -30,4 +30,7 @@ bundle inject \'rack\' \'> 0\'
 .IP "" 0
 .
 .P
-This will inject the \'rack\' gem with a version greater than 0 in your [\fBGemfile(5)\fR][Gemfile(5)] and Gemfile\.lock
+This will inject the \'rack\' gem with a version greater than 0 in your [\fBGemfile(5)\fR][Gemfile(5)] and Gemfile\.lock\.
+.
+.P
+The \fBbundle inject\fR command was deprecated in Bundler 2\.1 and will be removed in Bundler 3\.0\.
diff --git a/lib/bundler/man/bundle-inject.1.ronn b/lib/bundler/man/bundle-inject.1.ronn
index f454341896..95704eddad 100644
--- a/lib/bundler/man/bundle-inject.1.ronn
+++ b/lib/bundler/man/bundle-inject.1.ronn
@@ -19,4 +19,6 @@ Example:
     bundle inject 'rack' '> 0'
 
 This will inject the 'rack' gem with a version greater than 0 in your
-[`Gemfile(5)`][Gemfile(5)] and Gemfile.lock
+[`Gemfile(5)`][Gemfile(5)] and Gemfile.lock.
+
+The `bundle inject` command was deprecated in Bundler 2.1 and will be removed in Bundler 3.0.
diff --git a/lib/bundler/man/bundle-install.1 b/lib/bundler/man/bundle-install.1
index 734d4e2479..337683af06 100644
--- a/lib/bundler/man/bundle-install.1
+++ b/lib/bundler/man/bundle-install.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-INSTALL" "1" "March 2022" "" ""
+.TH "BUNDLE\-INSTALL" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-install\fR \- Install the dependencies specified in your Gemfile
@@ -70,6 +70,10 @@ The maximum number of parallel download and install jobs\. The default is the nu
 Do not attempt to connect to \fBrubygems\.org\fR\. Instead, Bundler will use the gems already present in Rubygems\' cache or in \fBvendor/cache\fR\. Note that if an appropriate platform\-specific gem exists on \fBrubygems\.org\fR it will not be found\.
 .
 .TP
+\fB\-\-prefer\-local\fR
+Force using locally installed gems, or gems already present in Rubygems\' cache or in \fBvendor/cache\fR, when resolving, even if newer versions are available remotely\. Only attempt to connect to \fBrubygems\.org\fR for gems that are not present locally\.
+.
+.TP
 \fB\-\-no\-cache\fR
 Do not update the cache in \fBvendor/cache\fR with the newly bundled gems\. This does not remove any gems in the cache but keeps the newly bundled gems from being cached during the install\.
 .
@@ -166,35 +170,6 @@ As a result, \fBbundle install \-\-deployment\fR installs gems to the \fBvendor/
 .
 .IP "" 0
 .
-.SH "SUDO USAGE"
-By default, Bundler installs gems to the same location as \fBgem install\fR\.
-.
-.P
-In some cases, that location may not be writable by your Unix user\. In that case, Bundler will stage everything in a temporary directory, then ask you for your \fBsudo\fR password in order to copy the gems into their system location\.
-.
-.P
-From your perspective, this is identical to installing the gems directly into the system\.
-.
-.P
-You should never use \fBsudo bundle install\fR\. This is because several other steps in \fBbundle install\fR must be performed as the current user:
-.
-.IP "\(bu" 4
-Updating your \fBGemfile\.lock\fR
-.
-.IP "\(bu" 4
-Updating your \fBvendor/cache\fR, if necessary
-.
-.IP "\(bu" 4
-Checking out private git repositories using your user\'s SSH keys
-.
-.IP "" 0
-.
-.P
-Of these three, the first two could theoretically be performed by \fBchown\fRing the resulting files to \fB$SUDO_USER\fR\. The third, however, can only be performed by invoking the \fBgit\fR command as the current user\. Therefore, git gems are downloaded and installed into \fB~/\.bundle\fR rather than $GEM_HOME or $BUNDLE_PATH\.
-.
-.P
-As a result, you should run \fBbundle install\fR as the current user, and Bundler will ask for your password if it is needed to put the gems into their final location\.
-.
 .SH "INSTALLING GROUPS"
 By default, \fBbundle install\fR will install all gems in all groups in your Gemfile(5), except those declared for a different platform\.
 .
diff --git a/lib/bundler/man/bundle-install.1.ronn b/lib/bundler/man/bundle-install.1.ronn
index bec05187f3..be9ed0f974 100644
--- a/lib/bundler/man/bundle-install.1.ronn
+++ b/lib/bundler/man/bundle-install.1.ronn
@@ -109,6 +109,12 @@ automatically and that requires `bundler` to silently remember them. Since
   appropriate platform-specific gem exists on `rubygems.org` it will not be
   found.
 
+* `--prefer-local`:
+  Force using locally installed gems, or gems already present in Rubygems' cache
+  or in `vendor/cache`, when resolving, even if newer versions are available
+  remotely. Only attempt to connect to `rubygems.org` for gems that are not
+  present locally.
+
 * `--no-cache`:
   Do not update the cache in `vendor/cache` with the newly bundled gems. This
   does not remove any gems in the cache but keeps the newly bundled gems from
@@ -218,35 +224,6 @@ will cause an error when the Gemfile(5) is modified.
    the `vendor/bundle` directory in the application. This may be
    overridden using the `--path` option.
 
-## SUDO USAGE
-
-By default, Bundler installs gems to the same location as `gem install`.
-
-In some cases, that location may not be writable by your Unix user. In
-that case, Bundler will stage everything in a temporary directory,
-then ask you for your `sudo` password in order to copy the gems into
-their system location.
-
-From your perspective, this is identical to installing the gems
-directly into the system.
-
-You should never use `sudo bundle install`. This is because several
-other steps in `bundle install` must be performed as the current user:
-
-* Updating your `Gemfile.lock`
-* Updating your `vendor/cache`, if necessary
-* Checking out private git repositories using your user's SSH keys
-
-Of these three, the first two could theoretically be performed by
-`chown`ing the resulting files to `$SUDO_USER`. The third, however,
-can only be performed by invoking the `git` command as
-the current user. Therefore, git gems are downloaded and installed
-into `~/.bundle` rather than $GEM_HOME or $BUNDLE_PATH.
-
-As a result, you should run `bundle install` as the current user,
-and Bundler will ask for your password if it is needed to put the
-gems into their final location.
-
 ## INSTALLING GROUPS
 
 By default, `bundle install` will install all gems in all groups
diff --git a/lib/bundler/man/bundle-list.1 b/lib/bundler/man/bundle-list.1
index aee07e7284..1680e6007a 100644
--- a/lib/bundler/man/bundle-list.1
+++ b/lib/bundler/man/bundle-list.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-LIST" "1" "March 2022" "" ""
+.TH "BUNDLE\-LIST" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-list\fR \- List all the gems in the bundle
diff --git a/lib/bundler/man/bundle-lock.1 b/lib/bundler/man/bundle-lock.1
index d107073c9c..8722c44b3d 100644
--- a/lib/bundler/man/bundle-lock.1
+++ b/lib/bundler/man/bundle-lock.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-LOCK" "1" "March 2022" "" ""
+.TH "BUNDLE\-LOCK" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-lock\fR \- Creates / Updates a lockfile without installing
diff --git a/lib/bundler/man/bundle-open.1 b/lib/bundler/man/bundle-open.1
index 41c58544e2..3513f0d09b 100644
--- a/lib/bundler/man/bundle-open.1
+++ b/lib/bundler/man/bundle-open.1
@@ -1,13 +1,13 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-OPEN" "1" "March 2022" "" ""
+.TH "BUNDLE\-OPEN" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-open\fR \- Opens the source directory for a gem in your bundle
 .
 .SH "SYNOPSIS"
-\fBbundle open\fR [GEM]
+\fBbundle open\fR [GEM] [\-\-path=PATH]
 .
 .SH "DESCRIPTION"
 Opens the source directory of the provided GEM in your editor\.
@@ -30,3 +30,23 @@ bundle open \'rack\'
 .
 .P
 Will open the source directory for the \'rack\' gem in your bundle\.
+.
+.IP "" 4
+.
+.nf
+
+bundle open \'rack\' \-\-path \'README\.md\'
+.
+.fi
+.
+.IP "" 0
+.
+.P
+Will open the README\.md file of the \'rack\' gem source in your bundle\.
+.
+.SH "OPTIONS"
+.
+.TP
+\fB\-\-path\fR
+Specify GEM source relative path to open\.
+
diff --git a/lib/bundler/man/bundle-open.1.ronn b/lib/bundler/man/bundle-open.1.ronn
index 497beac93f..a857f3a965 100644
--- a/lib/bundler/man/bundle-open.1.ronn
+++ b/lib/bundler/man/bundle-open.1.ronn
@@ -3,7 +3,7 @@ bundle-open(1) -- Opens the source directory for a gem in your bundle
 
 ## SYNOPSIS
 
-`bundle open` [GEM]
+`bundle open` [GEM] [--path=PATH]
 
 ## DESCRIPTION
 
@@ -17,3 +17,11 @@ Example:
     bundle open 'rack'
 
 Will open the source directory for the 'rack' gem in your bundle.
+
+    bundle open 'rack' --path 'README.md'
+
+Will open the README.md file of the 'rack' gem source in your bundle.
+
+## OPTIONS
+* `--path`:
+  Specify GEM source relative path to open.
diff --git a/lib/bundler/man/bundle-outdated.1 b/lib/bundler/man/bundle-outdated.1
index bb6149df34..129ff00f58 100644
--- a/lib/bundler/man/bundle-outdated.1
+++ b/lib/bundler/man/bundle-outdated.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-OUTDATED" "1" "March 2022" "" ""
+.TH "BUNDLE\-OUTDATED" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-outdated\fR \- List installed gems with newer versions available
@@ -83,9 +83,10 @@ If the regular output shows the following:
 .
 .nf
 
-* faker (newest 1\.6\.6, installed 1\.6\.5, requested ~> 1\.4) in groups "development, test"
-* hashie (newest 3\.4\.6, installed 1\.2\.0, requested = 1\.2\.0) in groups "default"
-* headless (newest 2\.3\.1, installed 2\.2\.3) in groups "test"
+* Gem       Current  Latest  Requested  Groups
+* faker     1\.6\.5    1\.6\.6   ~> 1\.4     development, test
+* hashie    1\.2\.0    3\.4\.6   = 1\.2\.0    default
+* headless  2\.2\.3    2\.3\.1   = 2\.2\.3    test
 .
 .fi
 .
@@ -98,7 +99,8 @@ If the regular output shows the following:
 .
 .nf
 
-* hashie (newest 3\.4\.6, installed 1\.2\.0, requested = 1\.2\.0) in groups "default"
+* Gem       Current  Latest  Requested  Groups
+* hashie    1\.2\.0    3\.4\.6   = 1\.2\.0    default
 .
 .fi
 .
@@ -111,7 +113,8 @@ If the regular output shows the following:
 .
 .nf
 
-* headless (newest 2\.3\.1, installed 2\.2\.3) in groups "test"
+* Gem       Current  Latest  Requested  Groups
+* headless  2\.2\.3    2\.3\.1   = 2\.2\.3    test
 .
 .fi
 .
@@ -124,7 +127,8 @@ If the regular output shows the following:
 .
 .nf
 
-* faker (newest 1\.6\.6, installed 1\.6\.5, requested ~> 1\.4) in groups "development, test"
+* Gem       Current  Latest  Requested  Groups
+* faker     1\.6\.5    1\.6\.6   ~> 1\.4     development, test
 .
 .fi
 .
@@ -137,8 +141,8 @@ Filter options can be combined\. \fB\-\-filter\-minor\fR and \fB\-\-filter\-patc
 .
 .nf
 
-* faker (newest 1\.6\.6, installed 1\.6\.5, requested ~> 1\.4) in groups "development, test"
-* headless (newest 2\.3\.1, installed 2\.2\.3) in groups "test"
+* Gem       Current  Latest  Requested  Groups
+* faker     1\.6\.5    1\.6\.6   ~> 1\.4     development, test
 .
 .fi
 .
diff --git a/lib/bundler/man/bundle-outdated.1.ronn b/lib/bundler/man/bundle-outdated.1.ronn
index 04096ffbb6..27bf21ab9d 100644
--- a/lib/bundler/man/bundle-outdated.1.ronn
+++ b/lib/bundler/man/bundle-outdated.1.ronn
@@ -78,25 +78,28 @@ in the output.
 
 If the regular output shows the following:
 
-    * faker (newest 1.6.6, installed 1.6.5, requested ~> 1.4) in groups "development, test"
-    * hashie (newest 3.4.6, installed 1.2.0, requested = 1.2.0) in groups "default"
-    * headless (newest 2.3.1, installed 2.2.3) in groups "test"
+    * Gem       Current  Latest  Requested  Groups
+    * faker     1.6.5    1.6.6   ~> 1.4     development, test
+    * hashie    1.2.0    3.4.6   = 1.2.0    default
+    * headless  2.2.3    2.3.1   = 2.2.3    test
 
 `--filter-major` would only show:
 
-    * hashie (newest 3.4.6, installed 1.2.0, requested = 1.2.0) in groups "default"
+    * Gem       Current  Latest  Requested  Groups
+    * hashie    1.2.0    3.4.6   = 1.2.0    default
 
 `--filter-minor` would only show:
 
-    * headless (newest 2.3.1, installed 2.2.3) in groups "test"
+    * Gem       Current  Latest  Requested  Groups
+    * headless  2.2.3    2.3.1   = 2.2.3    test
 
 `--filter-patch` would only show:
 
-    * faker (newest 1.6.6, installed 1.6.5, requested ~> 1.4) in groups "development, test"
+    * Gem       Current  Latest  Requested  Groups
+    * faker     1.6.5    1.6.6   ~> 1.4     development, test
 
 Filter options can be combined. `--filter-minor` and `--filter-patch` would show:
 
-    * faker (newest 1.6.6, installed 1.6.5, requested ~> 1.4) in groups "development, test"
-    * headless (newest 2.3.1, installed 2.2.3) in groups "test"
-
+    * Gem       Current  Latest  Requested  Groups
+    * faker     1.6.5    1.6.6   ~> 1.4     development, test
 Combining all three `filter` options would be the same result as providing none of them.
diff --git a/lib/bundler/man/bundle-platform.1 b/lib/bundler/man/bundle-platform.1
index fa9aa9c624..5021c46b4c 100644
--- a/lib/bundler/man/bundle-platform.1
+++ b/lib/bundler/man/bundle-platform.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-PLATFORM" "1" "March 2022" "" ""
+.TH "BUNDLE\-PLATFORM" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-platform\fR \- Displays platform compatibility information
@@ -10,7 +10,7 @@
 \fBbundle platform\fR [\-\-ruby]
 .
 .SH "DESCRIPTION"
-\fBplatform\fR will display information from your Gemfile, Gemfile\.lock, and Ruby VM about your platform\.
+\fBplatform\fR displays information from your Gemfile, Gemfile\.lock, and Ruby VM about your platform\.
 .
 .P
 For instance, using this Gemfile(5):
@@ -21,7 +21,7 @@ For instance, using this Gemfile(5):
 
 source "https://rubygems\.org"
 
-ruby "1\.9\.3"
+ruby "3\.1\.2"
 
 gem "rack"
 .
@@ -30,7 +30,7 @@ gem "rack"
 .IP "" 0
 .
 .P
-If you run \fBbundle platform\fR on Ruby 1\.9\.3, it will display the following output:
+If you run \fBbundle platform\fR on Ruby 3\.1\.2, it displays the following output:
 .
 .IP "" 4
 .
@@ -39,10 +39,13 @@ If you run \fBbundle platform\fR on Ruby 1\.9\.3, it will display the following
 Your platform is: x86_64\-linux
 
 Your app has gems that work on these platforms:
+* arm64\-darwin\-21
 * ruby
+* x64\-mingw\-ucrt
+* x86_64\-linux
 
 Your Gemfile specifies a Ruby version requirement:
-* ruby 1\.9\.3
+* ruby 3\.1\.2
 
 Your current platform satisfies the Ruby version requirement\.
 .
@@ -51,11 +54,18 @@ Your current platform satisfies the Ruby version requirement\.
 .IP "" 0
 .
 .P
-\fBplatform\fR will list all the platforms in your \fBGemfile\.lock\fR as well as the \fBruby\fR directive if applicable from your Gemfile(5)\. It will also let you know if the \fBruby\fR directive requirement has been met\. If \fBruby\fR directive doesn\'t match the running Ruby VM, it will tell you what part does not\.
+\fBplatform\fR lists all the platforms in your \fBGemfile\.lock\fR as well as the \fBruby\fR directive if applicable from your Gemfile(5)\. It also lets you know if the \fBruby\fR directive requirement has been met\. If \fBruby\fR directive doesn\'t match the running Ruby VM, it tells you what part does not\.
 .
 .SH "OPTIONS"
 .
 .TP
 \fB\-\-ruby\fR
 It will display the ruby directive information, so you don\'t have to parse it from the Gemfile(5)\.
+.
+.SH "SEE ALSO"
+.
+.IP "\(bu" 4
+bundle\-lock(1) \fIbundle\-lock\.1\.html\fR
+.
+.IP "" 0
 
diff --git a/lib/bundler/man/bundle-platform.1.ronn b/lib/bundler/man/bundle-platform.1.ronn
index b5d3283fb6..744acd1b43 100644
--- a/lib/bundler/man/bundle-platform.1.ronn
+++ b/lib/bundler/man/bundle-platform.1.ronn
@@ -7,36 +7,43 @@ bundle-platform(1) -- Displays platform compatibility information
 
 ## DESCRIPTION
 
-`platform` will display information from your Gemfile, Gemfile.lock, and Ruby
+`platform` displays information from your Gemfile, Gemfile.lock, and Ruby
 VM about your platform.
 
 For instance, using this Gemfile(5):
 
     source "https://rubygems.org"
 
-    ruby "1.9.3"
+    ruby "3.1.2"
 
     gem "rack"
 
-If you run `bundle platform` on Ruby 1.9.3, it will display the following output:
+If you run `bundle platform` on Ruby 3.1.2, it displays the following output:
 
     Your platform is: x86_64-linux
 
     Your app has gems that work on these platforms:
+    * arm64-darwin-21
     * ruby
+    * x64-mingw-ucrt
+    * x86_64-linux
 
     Your Gemfile specifies a Ruby version requirement:
-    * ruby 1.9.3
+    * ruby 3.1.2
 
     Your current platform satisfies the Ruby version requirement.
 
-`platform` will list all the platforms in your `Gemfile.lock` as well as the
-`ruby` directive if applicable from your Gemfile(5). It will also let you know
+`platform` lists all the platforms in your `Gemfile.lock` as well as the
+`ruby` directive if applicable from your Gemfile(5). It also lets you know
 if the `ruby` directive requirement has been met. If `ruby` directive doesn't
-match the running Ruby VM, it will tell you what part does not.
+match the running Ruby VM, it tells you what part does not.
 
 ## OPTIONS
 
 * `--ruby`:
   It will display the ruby directive information, so you don't have to
   parse it from the Gemfile(5).
+
+## SEE ALSO
+
+* [bundle-lock(1)](bundle-lock.1.html)
diff --git a/lib/bundler/man/bundle-plugin.1 b/lib/bundler/man/bundle-plugin.1
new file mode 100644
index 0000000000..ec30e1d0fd
--- /dev/null
+++ b/lib/bundler/man/bundle-plugin.1
@@ -0,0 +1,81 @@
+.\" generated with Ronn/v0.7.3
+.\" http://github.com/rtomayko/ronn/tree/0.7.3
+.
+.TH "BUNDLE\-PLUGIN" "1" "August 2023" "" ""
+.
+.SH "NAME"
+\fBbundle\-plugin\fR \- Manage Bundler plugins
+.
+.SH "SYNOPSIS"
+\fBbundle plugin\fR install PLUGINS [\-\-source=\fISOURCE\fR] [\-\-version=\fIversion\fR] [\-\-git|\-\-local_git=\fIgit\-url\fR] [\-\-branch=\fIbranch\fR|\-\-ref=\fIrev\fR]
+.
+.br
+\fBbundle plugin\fR uninstall PLUGINS
+.
+.br
+\fBbundle plugin\fR list
+.
+.br
+\fBbundle plugin\fR help [COMMAND]
+.
+.SH "DESCRIPTION"
+You can install, uninstall, and list plugin(s) with this command to extend functionalities of Bundler\.
+.
+.SH "SUB\-COMMANDS"
+.
+.SS "install"
+Install the given plugin(s)\.
+.
+.IP "\(bu" 4
+\fBbundle plugin install bundler\-graph\fR: Install bundler\-graph gem from RubyGems\.org\. The global source, specified in source in Gemfile is ignored\.
+.
+.IP "\(bu" 4
+\fBbundle plugin install bundler\-graph \-\-source https://example\.com\fR: Install bundler\-graph gem from example\.com\. The global source, specified in source in Gemfile is not considered\.
+.
+.IP "\(bu" 4
+\fBbundle plugin install bundler\-graph \-\-version 0\.2\.1\fR: You can specify the version of the gem via \fB\-\-version\fR\.
+.
+.IP "\(bu" 4
+\fBbundle plugin install bundler\-graph \-\-git https://github\.com/rubygems/bundler\-graph\fR: Install bundler\-graph gem from Git repository\. \fB\-\-git\fR can be replaced with \fB\-\-local\-git\fR\. You cannot use both \fB\-\-git\fR and \fB\-\-local\-git\fR\. You can use standard Git URLs like:
+.
+.IP "\(bu" 4
+\fBssh://[user@]host\.xz[:port]/path/to/repo\.git\fR
+.
+.IP "\(bu" 4
+\fBhttp[s]://host\.xz[:port]/path/to/repo\.git\fR
+.
+.IP "\(bu" 4
+\fB/path/to/repo\fR
+.
+.IP "\(bu" 4
+\fBfile:///path/to/repo\fR
+.
+.IP "" 0
+.
+.IP
+When you specify \fB\-\-git\fR/\fB\-\-local\-git\fR, you can use \fB\-\-branch\fR or \fB\-\-ref\fR to specify any branch, tag, or commit hash (revision) to use\. When you specify both, only the latter is used\.
+.
+.IP "" 0
+.
+.SS "uninstall"
+Uninstall the plugin(s) specified in PLUGINS\.
+.
+.SS "list"
+List the installed plugins and available commands\.
+.
+.P
+No options\.
+.
+.SS "help"
+Describe subcommands or one specific subcommand\.
+.
+.P
+No options\.
+.
+.SH "SEE ALSO"
+.
+.IP "\(bu" 4
+How to write a Bundler plugin \fIhttps://bundler\.io/guides/bundler_plugins\.html\fR
+.
+.IP "" 0
+
diff --git a/lib/bundler/man/bundle-plugin.1.ronn b/lib/bundler/man/bundle-plugin.1.ronn
new file mode 100644
index 0000000000..4f234eeba7
--- /dev/null
+++ b/lib/bundler/man/bundle-plugin.1.ronn
@@ -0,0 +1,59 @@
+bundle-plugin(1) -- Manage Bundler plugins
+==========================================
+
+## SYNOPSIS
+
+`bundle plugin` install PLUGINS [--source=<SOURCE>] [--version=<version>]
+                              [--git|--local_git=<git-url>] [--branch=<branch>|--ref=<rev>]<br>
+`bundle plugin` uninstall PLUGINS<br>
+`bundle plugin` list<br>
+`bundle plugin` help [COMMAND]
+
+## DESCRIPTION
+
+You can install, uninstall, and list plugin(s) with this command to extend functionalities of Bundler.
+
+## SUB-COMMANDS
+
+### install
+
+Install the given plugin(s).
+
+* `bundle plugin install bundler-graph`:
+  Install bundler-graph gem from RubyGems.org. The global source, specified in source in Gemfile is ignored.
+
+* `bundle plugin install bundler-graph --source https://example.com`:
+  Install bundler-graph gem from example.com. The global source, specified in source in Gemfile is not considered.
+
+* `bundle plugin install bundler-graph --version 0.2.1`:
+  You can specify the version of the gem via `--version`.
+
+* `bundle plugin install bundler-graph --git https://github.com/rubygems/bundler-graph`:
+  Install bundler-graph gem from Git repository. `--git` can be replaced with `--local-git`. You cannot use both `--git` and `--local-git`. You can use standard Git URLs like:
+
+  * `ssh://[user@]host.xz[:port]/path/to/repo.git`
+  * `http[s]://host.xz[:port]/path/to/repo.git`
+  * `/path/to/repo`
+  * `file:///path/to/repo`
+
+  When you specify `--git`/`--local-git`, you can use `--branch` or `--ref` to specify any branch, tag, or commit hash (revision) to use. When you specify both, only the latter is used.
+
+### uninstall
+
+Uninstall the plugin(s) specified in PLUGINS.
+
+### list
+
+List the installed plugins and available commands.
+
+No options.
+
+### help
+
+Describe subcommands or one specific subcommand.
+
+No options.
+
+## SEE ALSO
+
+* [How to write a Bundler plugin](https://bundler.io/guides/bundler_plugins.html)
diff --git a/lib/bundler/man/bundle-pristine.1 b/lib/bundler/man/bundle-pristine.1
index 23fc4ad279..af81c48d2b 100644
--- a/lib/bundler/man/bundle-pristine.1
+++ b/lib/bundler/man/bundle-pristine.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-PRISTINE" "1" "March 2022" "" ""
+.TH "BUNDLE\-PRISTINE" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-pristine\fR \- Restores installed gems to their pristine condition
diff --git a/lib/bundler/man/bundle-remove.1 b/lib/bundler/man/bundle-remove.1
index 47e5555860..d86cf134bd 100644
--- a/lib/bundler/man/bundle-remove.1
+++ b/lib/bundler/man/bundle-remove.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-REMOVE" "1" "March 2022" "" ""
+.TH "BUNDLE\-REMOVE" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-remove\fR \- Removes gems from the Gemfile
diff --git a/lib/bundler/man/bundle-show.1 b/lib/bundler/man/bundle-show.1
index 21f8879e7b..aa91176bf2 100644
--- a/lib/bundler/man/bundle-show.1
+++ b/lib/bundler/man/bundle-show.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-SHOW" "1" "March 2022" "" ""
+.TH "BUNDLE\-SHOW" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-show\fR \- Shows all the gems in your bundle, or the path to a gem
diff --git a/lib/bundler/man/bundle-update.1 b/lib/bundler/man/bundle-update.1
index 0e410cb8ce..e4e10ad23b 100644
--- a/lib/bundler/man/bundle-update.1
+++ b/lib/bundler/man/bundle-update.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-UPDATE" "1" "March 2022" "" ""
+.TH "BUNDLE\-UPDATE" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-update\fR \- Update your gems to the latest available versions
diff --git a/lib/bundler/man/bundle-version.1 b/lib/bundler/man/bundle-version.1
new file mode 100644
index 0000000000..5e3ed44600
--- /dev/null
+++ b/lib/bundler/man/bundle-version.1
@@ -0,0 +1,35 @@
+.\" generated with Ronn/v0.7.3
+.\" http://github.com/rtomayko/ronn/tree/0.7.3
+.
+.TH "BUNDLE\-VERSION" "1" "August 2023" "" ""
+.
+.SH "NAME"
+\fBbundle\-version\fR \- Prints Bundler version information
+.
+.SH "SYNOPSIS"
+\fBbundle version\fR
+.
+.SH "DESCRIPTION"
+Prints Bundler version information\.
+.
+.SH "OPTIONS"
+No options\.
+.
+.SH "EXAMPLE"
+Print the version of Bundler with build date and commit hash of the in the Git source\.
+.
+.IP "" 4
+.
+.nf
+
+bundle version
+.
+.fi
+.
+.IP "" 0
+.
+.P
+shows \fBBundler version 2\.3\.21 (2022\-08\-24 commit d54be5fdd8)\fR for example\.
+.
+.P
+cf\. \fBbundle \-\-version\fR shows \fBBundler version 2\.3\.21\fR\.
diff --git a/lib/bundler/man/bundle-version.1.ronn b/lib/bundler/man/bundle-version.1.ronn
new file mode 100644
index 0000000000..46c6f0b30a
--- /dev/null
+++ b/lib/bundler/man/bundle-version.1.ronn
@@ -0,0 +1,24 @@
+bundle-version(1) -- Prints Bundler version information
+=======================================================
+
+## SYNOPSIS
+
+`bundle version`
+
+## DESCRIPTION
+
+Prints Bundler version information.
+
+## OPTIONS
+
+No options.
+
+## EXAMPLE
+
+Print the version of Bundler with build date and commit hash of the in the Git source.
+
+    bundle version
+
+shows `Bundler version 2.3.21 (2022-08-24 commit d54be5fdd8)` for example.
+
+cf. `bundle --version` shows `Bundler version 2.3.21`.
diff --git a/lib/bundler/man/bundle-viz.1 b/lib/bundler/man/bundle-viz.1
index e6333aa478..d5330ec754 100644
--- a/lib/bundler/man/bundle-viz.1
+++ b/lib/bundler/man/bundle-viz.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-VIZ" "1" "March 2022" "" ""
+.TH "BUNDLE\-VIZ" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\-viz\fR \- Generates a visual dependency graph for your Gemfile
@@ -15,6 +15,9 @@
 .P
 The associated gems must also be installed via \fBbundle install(1)\fR \fIbundle\-install\.1\.html\fR\.
 .
+.P
+\fBviz\fR command was deprecated in Bundler 2\.2\. Use bundler\-graph plugin \fIhttps://github\.com/rubygems/bundler\-graph\fR instead\.
+.
 .SH "OPTIONS"
 .
 .TP
diff --git a/lib/bundler/man/bundle-viz.1.ronn b/lib/bundler/man/bundle-viz.1.ronn
index 701df5415e..f220256943 100644
--- a/lib/bundler/man/bundle-viz.1.ronn
+++ b/lib/bundler/man/bundle-viz.1.ronn
@@ -16,6 +16,8 @@ bundle-viz(1) -- Generates a visual dependency graph for your Gemfile
 
 The associated gems must also be installed via [`bundle install(1)`](bundle-install.1.html).
 
+`viz` command was deprecated in Bundler 2.2. Use [bundler-graph plugin](https://github.com/rubygems/bundler-graph) instead.
+
 ## OPTIONS
 
 * `--file`, `-f`:
diff --git a/lib/bundler/man/bundle.1 b/lib/bundler/man/bundle.1
index ef0b09f260..99c65a72b5 100644
--- a/lib/bundler/man/bundle.1
+++ b/lib/bundler/man/bundle.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE" "1" "March 2022" "" ""
+.TH "BUNDLE" "1" "August 2023" "" ""
 .
 .SH "NAME"
 \fBbundle\fR \- Ruby Dependency Management
@@ -43,8 +43,8 @@ Install the gems specified by the \fBGemfile\fR or \fBGemfile\.lock\fR
 Update dependencies to their latest versions
 .
 .TP
-\fBbundle package(1)\fR \fIbundle\-package\.1\.html\fR
-Package the \.gem files required by your application into the \fBvendor/cache\fR directory
+\fBbundle cache(1)\fR \fIbundle\-cache\.1\.html\fR
+Package the \.gem files required by your application into the \fBvendor/cache\fR directory (aliases: \fBbundle package\fR, \fBbundle pack\fR)
 .
 .TP
 \fBbundle exec(1)\fR \fIbundle\-exec\.1\.html\fR
@@ -55,7 +55,7 @@ Execute a script in the current bundle
 Specify and read configuration options for Bundler
 .
 .TP
-\fBbundle help(1)\fR
+\fBbundle help(1)\fR \fIbundle\-help\.1\.html\fR
 Display detailed help for each subcommand
 .
 .SH "UTILITIES"
@@ -81,7 +81,7 @@ Show the source location of a particular gem in the bundle
 Show all of the outdated gems in the current bundle
 .
 .TP
-\fBbundle console(1)\fR
+\fBbundle console(1)\fR (deprecated)
 Start an IRB session in the current bundle
 .
 .TP
@@ -93,7 +93,7 @@ Open an installed gem in the editor
 Generate a lockfile for your dependencies
 .
 .TP
-\fBbundle viz(1)\fR \fIbundle\-viz\.1\.html\fR
+\fBbundle viz(1)\fR \fIbundle\-viz\.1\.html\fR (deprecated)
 Generate a visual representation of your dependencies
 .
 .TP
@@ -120,6 +120,14 @@ Display warnings about common problems
 \fBbundle remove(1)\fR \fIbundle\-remove\.1\.html\fR
 Removes gems from the Gemfile
 .
+.TP
+\fBbundle plugin(1)\fR \fIbundle\-plugin\.1\.html\fR
+Manage Bundler plugins
+.
+.TP
+\fBbundle version(1)\fR \fIbundle\-version\.1\.html\fR
+Prints Bundler version information
+.
 .SH "PLUGINS"
 When running a command that isn\'t listed in PRIMARY COMMANDS or UTILITIES, Bundler will try to find an executable on your path named \fBbundler\-<command>\fR and execute it, passing down any extra arguments to it\.
 .
@@ -127,10 +135,7 @@ When running a command that isn\'t listed in PRIMARY COMMANDS or UTILITIES, Bund
 These commands are obsolete and should no longer be used:
 .
 .IP "\(bu" 4
-\fBbundle cache(1)\fR
-.
-.IP "\(bu" 4
-\fBbundle show(1)\fR
+\fBbundle inject(1)\fR
 .
 .IP "" 0
 
diff --git a/lib/bundler/man/bundle.1.ronn b/lib/bundler/man/bundle.1.ronn
index 5b1712394a..8245effabd 100644
--- a/lib/bundler/man/bundle.1.ronn
+++ b/lib/bundler/man/bundle.1.ronn
@@ -36,9 +36,9 @@ We divide `bundle` subcommands into primary commands and utilities:
 * [`bundle update(1)`](bundle-update.1.html):
   Update dependencies to their latest versions
 
-* [`bundle package(1)`](bundle-package.1.html):
+* [`bundle cache(1)`](bundle-cache.1.html):
   Package the .gem files required by your application into the
-  `vendor/cache` directory
+  `vendor/cache` directory (aliases: `bundle package`, `bundle pack`)
 
 * [`bundle exec(1)`](bundle-exec.1.html):
   Execute a script in the current bundle
@@ -46,7 +46,7 @@ We divide `bundle` subcommands into primary commands and utilities:
 * [`bundle config(1)`](bundle-config.1.html):
   Specify and read configuration options for Bundler
 
-* `bundle help(1)`:
+* [`bundle help(1)`](bundle-help.1.html):
   Display detailed help for each subcommand
 
 ## UTILITIES
@@ -67,7 +67,7 @@ We divide `bundle` subcommands into primary commands and utilities:
 * [`bundle outdated(1)`](bundle-outdated.1.html):
   Show all of the outdated gems in the current bundle
 
-* `bundle console(1)`:
+* `bundle console(1)` (deprecated):
   Start an IRB session in the current bundle
 
 * [`bundle open(1)`](bundle-open.1.html):
@@ -76,7 +76,7 @@ We divide `bundle` subcommands into primary commands and utilities:
 * [`bundle lock(1)`](bundle-lock.1.html):
   Generate a lockfile for your dependencies
 
-* [`bundle viz(1)`](bundle-viz.1.html):
+* [`bundle viz(1)`](bundle-viz.1.html) (deprecated):
   Generate a visual representation of your dependencies
 
 * [`bundle init(1)`](bundle-init.1.html):
@@ -97,6 +97,12 @@ We divide `bundle` subcommands into primary commands and utilities:
 * [`bundle remove(1)`](bundle-remove.1.html):
   Removes gems from the Gemfile
 
+* [`bundle plugin(1)`](bundle-plugin.1.html):
+  Manage Bundler plugins
+
+* [`bundle version(1)`](bundle-version.1.html):
+  Prints Bundler version information
+
 ## PLUGINS
 
 When running a command that isn't listed in PRIMARY COMMANDS or UTILITIES,
@@ -107,5 +113,4 @@ and execute it, passing down any extra arguments to it.
 
 These commands are obsolete and should no longer be used:
 
-* `bundle cache(1)`
-* `bundle show(1)`
+* `bundle inject(1)`
diff --git a/lib/bundler/man/gemfile.5 b/lib/bundler/man/gemfile.5
index cf98f48f67..352fa0f545 100644
--- a/lib/bundler/man/gemfile.5
+++ b/lib/bundler/man/gemfile.5
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "GEMFILE" "5" "March 2022" "" ""
+.TH "GEMFILE" "5" "August 2023" "" ""
 .
 .SH "NAME"
 \fBGemfile\fR \- A format for describing gem dependencies for Ruby programs
@@ -15,8 +15,8 @@ Place the \fBGemfile\fR in the root of the directory containing the associated c
 .SH "SYNTAX"
 A \fBGemfile\fR is evaluated as Ruby code, in a context which makes available a number of methods used to describe the gem requirements\.
 .
-.SH "GLOBAL SOURCES"
-At the top of the \fBGemfile\fR, add a line for the \fBRubygems\fR source that contains the gems listed in the \fBGemfile\fR\.
+.SH "GLOBAL SOURCE"
+At the top of the \fBGemfile\fR, add a single line for the \fBRubyGems\fR source that contains the gems listed in the \fBGemfile\fR\.
 .
 .IP "" 4
 .
@@ -29,10 +29,16 @@ source "https://rubygems\.org"
 .IP "" 0
 .
 .P
-It is possible, but not recommended as of Bundler 1\.7, to add multiple global \fBsource\fR lines\. Each of these \fBsource\fRs \fBMUST\fR be a valid Rubygems repository\.
+You can add only one global source\. In Bundler 1\.13, adding multiple global sources was deprecated\. The \fBsource\fR \fBMUST\fR be a valid RubyGems repository\.
 .
 .P
-Sources are checked for gems following the heuristics described in \fISOURCE PRIORITY\fR\. If a gem is found in more than one global source, Bundler will print a warning after installing the gem indicating which source was used, and listing the other sources where the gem is available\. A specific source can be selected for gems that need to use a non\-standard repository, suppressing this warning, by using the \fI\fB:source\fR option\fR or a \fI\fBsource\fR block\fR\.
+To use more than one source of RubyGems, you should use \fI\fBsource\fR block\fR\.
+.
+.P
+A source is checked for gems following the heuristics described in \fISOURCE PRIORITY\fR\.
+.
+.P
+\fBNote about a behavior of the feature deprecated in Bundler 1\.13\fR: If a gem is found in more than one global source, Bundler will print a warning after installing the gem indicating which source was used, and listing the other sources where the gem is available\. A specific source can be selected for gems that need to use a non\-standard repository, suppressing this warning, by using the \fI\fB:source\fR option\fR or \fBsource\fR block\.
 .
 .SS "CREDENTIALS"
 Some gem sources require a username and password\. Use bundle config(1) \fIbundle\-config\.1\.html\fR to set the username and password for any of the sources that need it\. The command must be run once on each computer that will install the Gemfile, but this keeps the credentials from being stored in plain text in version control\.
@@ -67,13 +73,26 @@ Credentials in the source URL will take precedence over credentials set using \f
 If your application requires a specific Ruby version or engine, specify your requirements using the \fBruby\fR method, with the following arguments\. All parameters are \fBOPTIONAL\fR unless otherwise specified\.
 .
 .SS "VERSION (required)"
-The version of Ruby that your application requires\. If your application requires an alternate Ruby engine, such as JRuby, Rubinius or TruffleRuby, this should be the Ruby version that the engine is compatible with\.
+The version of Ruby that your application requires\. If your application requires an alternate Ruby engine, such as JRuby, TruffleRuby, etc\., this should be the Ruby version that the engine is compatible with\.
 .
 .IP "" 4
 .
 .nf
 
-ruby "1\.9\.3"
+ruby "3\.1\.2"
+.
+.fi
+.
+.IP "" 0
+.
+.P
+If you wish to derive your Ruby version from a version file (ie \.ruby\-version), you can use the \fBfile\fR option instead\.
+.
+.IP "" 4
+.
+.nf
+
+ruby file: "\.ruby\-version"
 .
 .fi
 .
@@ -89,7 +108,7 @@ What exactly is an Engine? \- A Ruby engine is an implementation of the Ruby lan
 For background: the reference or original implementation of the Ruby programming language is called Matz\'s Ruby Interpreter \fIhttps://en\.wikipedia\.org/wiki/Ruby_MRI\fR, or MRI for short\. This is named after Ruby creator Yukihiro Matsumoto, also known as Matz\. MRI is also known as CRuby, because it is written in C\. MRI is the most widely used Ruby engine\.
 .
 .IP "\(bu" 4
-Other implementations \fIhttps://www\.ruby\-lang\.org/en/about/\fR of Ruby exist\. Some of the more well\-known implementations include Rubinius \fIhttps://rubinius\.com/\fR, and JRuby \fIhttp://jruby\.org/\fR\. Rubinius is an alternative implementation of Ruby written in Ruby\. JRuby is an implementation of Ruby on the JVM, short for Java Virtual Machine\.
+Other implementations \fIhttps://www\.ruby\-lang\.org/en/about/\fR of Ruby exist\. Some of the more well\-known implementations include JRuby \fIhttp://jruby\.org/\fR and TruffleRuby \fIhttps://www\.graalvm\.org/ruby/\fR\. Rubinius is an alternative implementation of Ruby written in Ruby\. JRuby is an implementation of Ruby on the JVM, short for Java Virtual Machine\. TruffleRuby is a Ruby implementation on the GraalVM, a language toolkit built on the JVM\.
 .
 .IP "" 0
 .
@@ -100,20 +119,23 @@ Each application \fImay\fR specify a Ruby engine version\. If an engine version
 .
 .nf
 
-ruby "1\.8\.7", :engine => "jruby", :engine_version => "1\.6\.7"
+ruby "2\.6\.8", engine: "jruby", engine_version: "9\.3\.8\.0"
 .
 .fi
 .
 .IP "" 0
 .
 .SS "PATCHLEVEL"
-Each application \fImay\fR specify a Ruby patchlevel\.
+Each application \fImay\fR specify a Ruby patchlevel\. Specifying the patchlevel has been meaningless since Ruby 2\.1\.0 was released as the patchlevel is now uniquely determined by a combination of major, minor, and teeny version numbers\.
+.
+.P
+This option was implemented in Bundler 1\.4\.0 for Ruby 2\.0 or earlier\.
 .
 .IP "" 4
 .
 .nf
 
-ruby "2\.0\.0", :patchlevel => "247"
+ruby "3\.1\.2", patchlevel: "20"
 .
 .fi
 .
@@ -156,9 +178,9 @@ Each \fIgem\fR \fBMAY\fR specify files that should be used when autorequiring vi
 .
 .nf
 
-gem "redis", :require => ["redis/connection/hiredis", "redis"]
-gem "webmock", :require => false
-gem "byebug", :require => true
+gem "redis", require: ["redis/connection/hiredis", "redis"]
+gem "webmock", require: false
+gem "byebug", require: true
 .
 .fi
 .
@@ -172,8 +194,8 @@ The argument defaults to the name of the gem\. For example, these are identical:
 .nf
 
 gem "nokogiri"
-gem "nokogiri", :require => "nokogiri"
-gem "nokogiri", :require => true
+gem "nokogiri", require: "nokogiri"
+gem "nokogiri", require: true
 .
 .fi
 .
@@ -186,8 +208,8 @@ Each \fIgem\fR \fBMAY\fR specify membership in one or more groups\. Any \fIgem\f
 .
 .nf
 
-gem "rspec", :group => :test
-gem "wirble", :groups => [:development, :test]
+gem "rspec", group: :test
+gem "wirble", groups: [:development, :test]
 .
 .fi
 .
@@ -248,19 +270,23 @@ There are a number of \fBGemfile\fR platforms:
 .
 .TP
 \fBruby\fR
-C Ruby (MRI), Rubinius or TruffleRuby, but \fBNOT\fR Windows
+C Ruby (MRI), Rubinius, or TruffleRuby, but not Windows
 .
 .TP
 \fBmri\fR
-Same as \fIruby\fR, but only C Ruby (MRI)
+C Ruby (MRI) only, but not Windows
 .
 .TP
-\fBmingw\fR
-Windows 32 bit \'mingw32\' platform (aka RubyInstaller)
+\fBwindows\fR
+Windows C Ruby (MRI), including RubyInstaller 32\-bit and 64\-bit versions
 .
 .TP
-\fBx64_mingw\fR
-Windows 64 bit \'mingw32\' platform (aka RubyInstaller x64)
+\fBmswin\fR
+Windows C Ruby (MRI), including RubyInstaller 32\-bit versions
+.
+.TP
+\fBmswin64\fR
+Windows C Ruby (MRI), including RubyInstaller 64\-bit versions
 .
 .TP
 \fBrbx\fR
@@ -274,84 +300,82 @@ JRuby
 \fBtruffleruby\fR
 TruffleRuby
 .
-.TP
-\fBmswin\fR
-Windows
-.
 .P
-You can restrict further by platform and version for all platforms \fIexcept\fR for \fBrbx\fR, \fBjruby\fR, \fBtruffleruby\fR and \fBmswin\fR\.
-.
-.P
-To specify a version in addition to a platform, append the version number without the delimiter to the platform\. For example, to specify that a gem should only be used on platforms with Ruby 2\.3, use:
+On platforms \fBruby\fR, \fBmri\fR, \fBmswin\fR, \fBmswin64\fR, and \fBwindows\fR, you may additionally specify a version by appending the major and minor version numbers without a delimiter\. For example, to specify that a gem should only be used on platform \fBruby\fR version 3\.1, use:
 .
 .IP "" 4
 .
 .nf
 
-ruby_23
+ruby_31
 .
 .fi
 .
 .IP "" 0
 .
 .P
-The full list of platforms and supported versions includes:
+As with groups (above), you may specify one or more platforms:
 .
-.TP
-\fBruby\fR
-1\.8, 1\.9, 2\.0, 2\.1, 2\.2, 2\.3, 2\.4, 2\.5, 2\.6
+.IP "" 4
 .
-.TP
-\fBmri\fR
-1\.8, 1\.9, 2\.0, 2\.1, 2\.2, 2\.3, 2\.4, 2\.5, 2\.6
+.nf
+
+gem "weakling",   platforms: :jruby
+gem "ruby\-debug", platforms: :mri_31
+gem "nokogiri",   platforms: [:windows_31, :jruby]
 .
-.TP
-\fBmingw\fR
-1\.8, 1\.9, 2\.0, 2\.1, 2\.2, 2\.3, 2\.4, 2\.5, 2\.6
+.fi
 .
-.TP
-\fBx64_mingw\fR
-2\.0, 2\.1, 2\.2, 2\.3, 2\.4, 2\.5, 2\.6
+.IP "" 0
 .
 .P
-As with groups, you can specify one or more platforms:
+All operations involving groups (\fBbundle install\fR \fIbundle\-install\.1\.html\fR, \fBBundler\.setup\fR, \fBBundler\.require\fR) behave exactly the same as if any groups not matching the current platform were explicitly excluded\.
+.
+.SS "FORCE_RUBY_PLATFORM"
+If you always want the pure ruby variant of a gem to be chosen over platform specific variants, you can use the \fBforce_ruby_platform\fR option:
 .
 .IP "" 4
 .
 .nf
 
-gem "weakling",   :platforms => :jruby
-gem "ruby\-debug", :platforms => :mri_18
-gem "nokogiri",   :platforms => [:mri_18, :jruby]
+gem "ffi", force_ruby_platform: true
 .
 .fi
 .
 .IP "" 0
 .
 .P
-All operations involving groups (\fBbundle install\fR \fIbundle\-install\.1\.html\fR, \fBBundler\.setup\fR, \fBBundler\.require\fR) behave exactly the same as if any groups not matching the current platform were explicitly excluded\.
+This can be handy (assuming the pure ruby variant works fine) when:
+.
+.IP "\(bu" 4
+You\'re having issues with the platform specific variant\.
+.
+.IP "\(bu" 4
+The platform specific variant does not yet support a newer ruby (and thus has a \fBrequired_ruby_version\fR upper bound), but you still want your Gemfile{\.lock} files to resolve under that ruby\.
+.
+.IP "" 0
 .
 .SS "SOURCE"
-You can select an alternate Rubygems repository for a gem using the \':source\' option\.
+You can select an alternate RubyGems repository for a gem using the \':source\' option\.
 .
 .IP "" 4
 .
 .nf
 
-gem "some_internal_gem", :source => "https://gems\.example\.com"
+gem "some_internal_gem", source: "https://gems\.example\.com"
 .
 .fi
 .
 .IP "" 0
 .
 .P
-This forces the gem to be loaded from this source and ignores any global sources declared at the top level of the file\. If the gem does not exist in this source, it will not be installed\.
+This forces the gem to be loaded from this source and ignores the global source declared at the top level of the file\. If the gem does not exist in this source, it will not be installed\.
 .
 .P
-Bundler will search for child dependencies of this gem by first looking in the source selected for the parent, but if they are not found there, it will fall back on global sources using the ordering described in \fISOURCE PRIORITY\fR\.
+Bundler will search for child dependencies of this gem by first looking in the source selected for the parent, but if they are not found there, it will fall back on the global source\.
 .
 .P
-Selecting a specific source repository this way also suppresses the ambiguous gem warning described above in \fIGLOBAL SOURCES (#source)\fR\.
+\fBNote about a behavior of the feature deprecated in Bundler 1\.13\fR: Selecting a specific source repository this way also suppresses the ambiguous gem warning described above in \fIGLOBAL SOURCE\fR\.
 .
 .P
 Using the \fB:source\fR option for an individual gem will also make that source available as a possible global source for any other gems which do not specify explicit sources\. Thus, when adding gems with explicit sources, it is recommended that you also ensure all other gems in the Gemfile are using explicit sources\.
@@ -361,15 +385,15 @@ If necessary, you can specify that a gem is located at a particular git reposito
 .
 .TP
 \fBHTTP(S)\fR
-gem "rails", :git => "https://github\.com/rails/rails\.git"
+gem "rails", git: "https://github\.com/rails/rails\.git"
 .
 .TP
 \fBSSH\fR
-gem "rails", :git => "git@github\.com:rails/rails\.git"
+gem "rails", git: "git@github\.com:rails/rails\.git"
 .
 .TP
 \fBgit\fR
-gem "rails", :git => "git://github\.com/rails/rails\.git"
+gem "rails", git: "git://github\.com/rails/rails\.git"
 .
 .P
 If using SSH, the user that you use to run \fBbundle install\fR \fBMUST\fR have the appropriate keys available in their \fB$HOME/\.ssh\fR\.
@@ -393,7 +417,7 @@ If a git repository does have a \fB\.gemspec\fR for the gem you attached it to,
 .
 .nf
 
-gem "rails", "2\.3\.8", :git => "https://github\.com/rails/rails\.git"
+gem "rails", "2\.3\.8", git: "https://github\.com/rails/rails\.git"
 # bundle install will fail, because the \.gemspec in the rails
 # repository\'s master branch specifies version 3\.0\.0
 .
@@ -409,20 +433,20 @@ Git repositories support a number of additional options\.
 .
 .TP
 \fBbranch\fR, \fBtag\fR, and \fBref\fR
-You \fBMUST\fR only specify at most one of these options\. The default is \fB:branch => "master"\fR\. For example:
+You \fBMUST\fR only specify at most one of these options\. The default is \fBbranch: "master"\fR\. For example:
 .
 .IP
-gem "rails", :git => "https://github\.com/rails/rails\.git", :branch => "5\-0\-stable"
+gem "rails", git: "https://github\.com/rails/rails\.git", branch: "5\-0\-stable"
 .
 .IP
-gem "rails", :git => "https://github\.com/rails/rails\.git", :tag => "v5\.0\.0"
+gem "rails", git: "https://github\.com/rails/rails\.git", tag: "v5\.0\.0"
 .
 .IP
-gem "rails", :git => "https://github\.com/rails/rails\.git", :ref => "4aded"
+gem "rails", git: "https://github\.com/rails/rails\.git", ref: "4aded"
 .
 .TP
 \fBsubmodules\fR
-For reference, a git submodule \fIhttps://git\-scm\.com/book/en/v2/Git\-Tools\-Submodules\fR lets you have another git repository within a subfolder of your repository\. Specify \fB:submodules => true\fR to cause bundler to expand any submodules included in the git repository
+For reference, a git submodule \fIhttps://git\-scm\.com/book/en/v2/Git\-Tools\-Submodules\fR lets you have another git repository within a subfolder of your repository\. Specify \fBsubmodules: true\fR to cause bundler to expand any submodules included in the git repository
 .
 .P
 If a git repository contains multiple \fB\.gemspecs\fR, each \fB\.gemspec\fR represents a gem located at the same place in the file system as the \fB\.gemspec\fR\.
@@ -454,7 +478,7 @@ A custom git source can be defined via the \fBgit_source\fR method\. Provide the
 .nf
 
 git_source(:stash){ |repo_name| "https://stash\.corp\.acme\.pl/#{repo_name}\.git" }
-gem \'rails\', :stash => \'forks/rails\'
+gem \'rails\', stash: \'forks/rails\'
 .
 .fi
 .
@@ -467,7 +491,7 @@ In addition, if you wish to choose a specific branch:
 .
 .nf
 
-gem "rails", :stash => "forks/rails", :branch => "branch_name"
+gem "rails", stash: "forks/rails", branch: "branch_name"
 .
 .fi
 .
@@ -483,8 +507,8 @@ If the git repository you want to use is hosted on GitHub and is public, you can
 .
 .nf
 
-gem "rails", :github => "rails/rails"
-gem "rails", :github => "rails"
+gem "rails", github: "rails/rails"
+gem "rails", github: "rails"
 .
 .fi
 .
@@ -497,7 +521,7 @@ Are both equivalent to
 .
 .nf
 
-gem "rails", :git => "git://github\.com/rails/rails\.git"
+gem "rails", git: "https://github\.com/rails/rails\.git"
 .
 .fi
 .
@@ -513,7 +537,7 @@ You can also directly pass a pull request URL:
 .
 .nf
 
-gem "rails", :github => "https://github\.com/rails/rails/pull/43753"
+gem "rails", github: "https://github\.com/rails/rails/pull/43753"
 .
 .fi
 .
@@ -526,7 +550,7 @@ Which is equivalent to:
 .
 .nf
 
-gem "rails", :github => "rails/rails", branch: "refs/pull/43753/head"
+gem "rails", github: "rails/rails", branch: "refs/pull/43753/head"
 .
 .fi
 .
@@ -539,7 +563,7 @@ If the git repository you want to use is hosted as a GitHub Gist and is public,
 .
 .nf
 
-gem "the_hatch", :gist => "4815162342"
+gem "the_hatch", gist: "4815162342"
 .
 .fi
 .
@@ -552,7 +576,7 @@ Is equivalent to:
 .
 .nf
 
-gem "the_hatch", :git => "https://gist\.github\.com/4815162342\.git"
+gem "the_hatch", git: "https://gist\.github\.com/4815162342\.git"
 .
 .fi
 .
@@ -568,8 +592,8 @@ If the git repository you want to use is hosted on Bitbucket and is public, you
 .
 .nf
 
-gem "rails", :bitbucket => "rails/rails"
-gem "rails", :bitbucket => "rails"
+gem "rails", bitbucket: "rails/rails"
+gem "rails", bitbucket: "rails"
 .
 .fi
 .
@@ -582,7 +606,7 @@ Are both equivalent to
 .
 .nf
 
-gem "rails", :git => "https://rails@bitbucket\.org/rails/rails\.git"
+gem "rails", git: "https://rails@bitbucket\.org/rails/rails\.git"
 .
 .fi
 .
@@ -604,7 +628,7 @@ Unlike \fB:git\fR, bundler does not compile C extensions for gems specified as p
 .
 .nf
 
-gem "rails", :path => "vendor/rails"
+gem "rails", path: "vendor/rails"
 .
 .fi
 .
@@ -648,7 +672,7 @@ platforms :ruby do
   gem "sqlite3"
 end
 
-group :development, :optional => true do
+group :development, optional: true do
   gem "wirble"
   gem "faker"
 end
@@ -688,10 +712,10 @@ The \fB\.gemspec\fR \fIhttp://guides\.rubygems\.org/specification\-reference/\fR
 If you wish to use Bundler to help install dependencies for a gem while it is being developed, use the \fBgemspec\fR method to pull in the dependencies listed in the \fB\.gemspec\fR file\.
 .
 .P
-The \fBgemspec\fR method adds any runtime dependencies as gem requirements in the default group\. It also adds development dependencies as gem requirements in the \fBdevelopment\fR group\. Finally, it adds a gem requirement on your project (\fB:path => \'\.\'\fR)\. In conjunction with \fBBundler\.setup\fR, this allows you to require project files in your test code as you would if the project were installed as a gem; you need not manipulate the load path manually or require project files via relative paths\.
+The \fBgemspec\fR method adds any runtime dependencies as gem requirements in the default group\. It also adds development dependencies as gem requirements in the \fBdevelopment\fR group\. Finally, it adds a gem requirement on your project (\fBpath: \'\.\'\fR)\. In conjunction with \fBBundler\.setup\fR, this allows you to require project files in your test code as you would if the project were installed as a gem; you need not manipulate the load path manually or require project files via relative paths\.
 .
 .P
-The \fBgemspec\fR method supports optional \fB:path\fR, \fB:glob\fR, \fB:name\fR, and \fB:development_group\fR options, which control where bundler looks for the \fB\.gemspec\fR, the glob it uses to look for the gemspec (defaults to: "{,\fI,\fR/*}\.gemspec"), what named \fB\.gemspec\fR it uses (if more than one is present), and which group development dependencies are included in\.
+The \fBgemspec\fR method supports optional \fB:path\fR, \fB:glob\fR, \fB:name\fR, and \fB:development_group\fR options, which control where bundler looks for the \fB\.gemspec\fR, the glob it uses to look for the gemspec (defaults to: \fB{,*,*/*}\.gemspec\fR), what named \fB\.gemspec\fR it uses (if more than one is present), and which group development dependencies are included in\.
 .
 .P
 When a \fBgemspec\fR dependency encounters version conflicts during resolution, the local version under development will always be selected \-\- even if there are remote versions that better match other requirements for the \fBgemspec\fR gem\.
@@ -706,7 +730,7 @@ The source explicitly attached to the gem (using \fB:source\fR, \fB:path\fR, or
 For implicit gems (dependencies of explicit gems), any source, git, or path repository declared on the parent\. This results in bundler prioritizing the ActiveSupport gem from the Rails git repository over ones from \fBrubygems\.org\fR
 .
 .IP "3." 4
-The sources specified via global \fBsource\fR lines, searching each source in your \fBGemfile\fR from last added to first added\.
+If neither of the above conditions are met, the global source will be used\. If multiple global sources are specified, they will be prioritized from last to first, but this is deprecated since Bundler 1\.13, so Bundler prints a warning and will abort with an error in the future\.
 .
 .IP "" 0
 
diff --git a/lib/bundler/man/gemfile.5.ronn b/lib/bundler/man/gemfile.5.ronn
index 0feaf58246..6749c33f59 100644
--- a/lib/bundler/man/gemfile.5.ronn
+++ b/lib/bundler/man/gemfile.5.ronn
@@ -15,23 +15,28 @@ directory as the `Rakefile`.
 A `Gemfile` is evaluated as Ruby code, in a context which makes available
 a number of methods used to describe the gem requirements.
 
-## GLOBAL SOURCES
+## GLOBAL SOURCE
 
-At the top of the `Gemfile`, add a line for the `Rubygems` source that contains
-the gems listed in the `Gemfile`.
+At the top of the `Gemfile`, add a single line for the `RubyGems` source that
+contains the gems listed in the `Gemfile`.
 
     source "https://rubygems.org"
 
-It is possible, but not recommended as of Bundler 1.7, to add multiple global
-`source` lines. Each of these `source`s `MUST` be a valid Rubygems repository.
+You can add only one global source. In Bundler 1.13, adding multiple global
+sources was deprecated. The `source` `MUST` be a valid RubyGems repository.
 
-Sources are checked for gems following the heuristics described in
-[SOURCE PRIORITY][]. If a gem is found in more than one global source, Bundler
+To use more than one source of RubyGems, you should use [`source` block
+](#BLOCK-FORM-OF-SOURCE-GIT-PATH-GROUP-and-PLATFORMS).
+
+A source is checked for gems following the heuristics described in
+[SOURCE PRIORITY][].
+
+**Note about a behavior of the feature deprecated in Bundler 1.13**:
+If a gem is found in more than one global source, Bundler
 will print a warning after installing the gem indicating which source was used,
 and listing the other sources where the gem is available. A specific source can
 be selected for gems that need to use a non-standard repository, suppressing
-this warning, by using the [`:source` option](#SOURCE) or a
-[`source` block](#BLOCK-FORM-OF-SOURCE-GIT-PATH-GROUP-and-PLATFORMS).
+this warning, by using the [`:source` option](#SOURCE) or `source` block.
 
 ### CREDENTIALS
 
@@ -59,10 +64,15 @@ All parameters are `OPTIONAL` unless otherwise specified.
 ### VERSION (required)
 
 The version of Ruby that your application requires. If your application
-requires an alternate Ruby engine, such as JRuby, Rubinius or TruffleRuby, this
+requires an alternate Ruby engine, such as JRuby, TruffleRuby, etc., this
 should be the Ruby version that the engine is compatible with.
 
-    ruby "1.9.3"
+    ruby "3.1.2"
+
+If you wish to derive your Ruby version from a version file (ie .ruby-version),
+you can use the `file` option instead.
+
+    ruby file: ".ruby-version"
 
 ### ENGINE
 
@@ -81,9 +91,10 @@ What exactly is an Engine?
 
   - [Other implementations](https://www.ruby-lang.org/en/about/) of Ruby exist.
     Some of the more well-known implementations include
-    [Rubinius](https://rubinius.com/), and [JRuby](http://jruby.org/).
+    [JRuby](http://jruby.org/) and [TruffleRuby](https://www.graalvm.org/ruby/).
     Rubinius is an alternative implementation of Ruby written in Ruby.
     JRuby is an implementation of Ruby on the JVM, short for Java Virtual Machine.
+    TruffleRuby is a Ruby implementation on the GraalVM, a language toolkit built on the JVM.
 
 ### ENGINE VERSION
 
@@ -91,13 +102,17 @@ Each application _may_ specify a Ruby engine version. If an engine version is
 specified, an engine _must_ also be specified. If the engine is "ruby" the
 engine version specified _must_ match the Ruby version.
 
-    ruby "1.8.7", :engine => "jruby", :engine_version => "1.6.7"
+    ruby "2.6.8", engine: "jruby", engine_version: "9.3.8.0"
 
 ### PATCHLEVEL
 
-Each application _may_ specify a Ruby patchlevel.
+Each application _may_ specify a Ruby patchlevel. Specifying the patchlevel has
+been meaningless since Ruby 2.1.0 was released as the patchlevel is now
+uniquely determined by a combination of major, minor, and teeny version numbers.
+
+This option was implemented in Bundler 1.4.0 for Ruby 2.0 or earlier.
 
-    ruby "2.0.0", :patchlevel => "247"
+    ruby "3.1.2", patchlevel: "20"
 
 ## GEMS
 
@@ -124,23 +139,23 @@ Each _gem_ `MAY` specify files that should be used when autorequiring via
 you want `required` has the same name as _gem_ or `false` to
 prevent any file from being autorequired.
 
-    gem "redis", :require => ["redis/connection/hiredis", "redis"]
-    gem "webmock", :require => false
-    gem "byebug", :require => true
+    gem "redis", require: ["redis/connection/hiredis", "redis"]
+    gem "webmock", require: false
+    gem "byebug", require: true
 
 The argument defaults to the name of the gem. For example, these are identical:
 
     gem "nokogiri"
-    gem "nokogiri", :require => "nokogiri"
-    gem "nokogiri", :require => true
+    gem "nokogiri", require: "nokogiri"
+    gem "nokogiri", require: true
 
 ### GROUPS
 
 Each _gem_ `MAY` specify membership in one or more groups. Any _gem_ that does
 not specify membership in any group is placed in the `default` group.
 
-    gem "rspec", :group => :test
-    gem "wirble", :groups => [:development, :test]
+    gem "rspec", group: :test
+    gem "wirble", groups: [:development, :test]
 
 The Bundler runtime allows its two main methods, `Bundler.setup` and
 `Bundler.require`, to limit their impact to particular groups.
@@ -185,70 +200,71 @@ platforms.
 There are a number of `Gemfile` platforms:
 
   * `ruby`:
-    C Ruby (MRI), Rubinius or TruffleRuby, but `NOT` Windows
+    C Ruby (MRI), Rubinius, or TruffleRuby, but not Windows
   * `mri`:
-    Same as _ruby_, but only C Ruby (MRI)
-  * `mingw`:
-    Windows 32 bit 'mingw32' platform (aka RubyInstaller)
-  * `x64_mingw`:
-    Windows 64 bit 'mingw32' platform (aka RubyInstaller x64)
+    C Ruby (MRI) only, but not Windows
+  * `windows`:
+    Windows C Ruby (MRI), including RubyInstaller 32-bit and 64-bit versions
+  * `mswin`:
+    Windows C Ruby (MRI), including RubyInstaller 32-bit versions
+  * `mswin64`:
+    Windows C Ruby (MRI), including RubyInstaller 64-bit versions
   * `rbx`:
     Rubinius
   * `jruby`:
     JRuby
   * `truffleruby`:
     TruffleRuby
-  * `mswin`:
-    Windows
 
-You can restrict further by platform and version for all platforms *except* for
-`rbx`, `jruby`, `truffleruby` and `mswin`.
+On platforms `ruby`, `mri`, `mswin`, `mswin64`, and `windows`, you may
+additionally specify a version by appending the major and minor version numbers
+without a delimiter. For example, to specify that a gem should only be used on
+platform `ruby` version 3.1, use:
 
-To specify a version in addition to a platform, append the version number without
-the delimiter to the platform. For example, to specify that a gem should only be
-used on platforms with Ruby 2.3, use:
+    ruby_31
 
-    ruby_23
+As with groups (above), you may specify one or more platforms:
 
-The full list of platforms and supported versions includes:
-
-  * `ruby`:
-    1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6
-  * `mri`:
-    1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6
-  * `mingw`:
-    1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6
-  * `x64_mingw`:
-    2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6
-
-As with groups, you can specify one or more platforms:
-
-    gem "weakling",   :platforms => :jruby
-    gem "ruby-debug", :platforms => :mri_18
-    gem "nokogiri",   :platforms => [:mri_18, :jruby]
+    gem "weakling",   platforms: :jruby
+    gem "ruby-debug", platforms: :mri_31
+    gem "nokogiri",   platforms: [:windows_31, :jruby]
 
 All operations involving groups ([`bundle install`](bundle-install.1.html), `Bundler.setup`,
 `Bundler.require`) behave exactly the same as if any groups not
 matching the current platform were explicitly excluded.
 
+### FORCE_RUBY_PLATFORM
+
+If you always want the pure ruby variant of a gem to be chosen over platform
+specific variants, you can use the `force_ruby_platform` option:
+
+    gem "ffi", force_ruby_platform: true
+
+This can be handy (assuming the pure ruby variant works fine) when:
+
+* You're having issues with the platform specific variant.
+* The platform specific variant does not yet support a newer ruby (and thus has
+  a `required_ruby_version` upper bound), but you still want your Gemfile{.lock}
+  files to resolve under that ruby.
+
 ### SOURCE
 
-You can select an alternate Rubygems repository for a gem using the ':source'
+You can select an alternate RubyGems repository for a gem using the ':source'
 option.
 
-    gem "some_internal_gem", :source => "https://gems.example.com"
+    gem "some_internal_gem", source: "https://gems.example.com"
 
-This forces the gem to be loaded from this source and ignores any global sources
+This forces the gem to be loaded from this source and ignores the global source
 declared at the top level of the file. If the gem does not exist in this source,
 it will not be installed.
 
 Bundler will search for child dependencies of this gem by first looking in the
 source selected for the parent, but if they are not found there, it will fall
-back on global sources using the ordering described in [SOURCE PRIORITY][].
+back on the global source.
 
+**Note about a behavior of the feature deprecated in Bundler 1.13**:
 Selecting a specific source repository this way also suppresses the ambiguous
-gem warning described above in
-[GLOBAL SOURCES (#source)](#GLOBAL-SOURCES).
+gem warning described above in [GLOBAL SOURCE](#GLOBAL-SOURCE).
 
 Using the `:source` option for an individual gem will also make that source
 available as a possible global source for any other gems which do not specify
@@ -263,11 +279,11 @@ git repository using the `:git` parameter. The repository can be accessed via
 several protocols:
 
   * `HTTP(S)`:
-    gem "rails", :git => "https://github.com/rails/rails.git"
+    gem "rails", git: "https://github.com/rails/rails.git"
   * `SSH`:
-    gem "rails", :git => "git@github.com:rails/rails.git"
+    gem "rails", git: "git@github.com:rails/rails.git"
   * `git`:
-    gem "rails", :git => "git://github.com/rails/rails.git"
+    gem "rails", git: "git://github.com/rails/rails.git"
 
 If using SSH, the user that you use to run `bundle install` `MUST` have the
 appropriate keys available in their `$HOME/.ssh`.
@@ -295,7 +311,7 @@ to, a version specifier, if provided, means that the git repository is
 only valid if the `.gemspec` specifies a version matching the version
 specifier. If not, bundler will print a warning.
 
-    gem "rails", "2.3.8", :git => "https://github.com/rails/rails.git"
+    gem "rails", "2.3.8", git: "https://github.com/rails/rails.git"
     # bundle install will fail, because the .gemspec in the rails
     # repository's master branch specifies version 3.0.0
 
@@ -307,18 +323,18 @@ Git repositories support a number of additional options.
 
   * `branch`, `tag`, and `ref`:
     You `MUST` only specify at most one of these options. The default
-    is `:branch => "master"`.  For example:
+    is `branch: "master"`.  For example:
 
-      gem "rails", :git => "https://github.com/rails/rails.git", :branch => "5-0-stable"
+      gem "rails", git: "https://github.com/rails/rails.git", branch: "5-0-stable"
 
-      gem "rails", :git => "https://github.com/rails/rails.git", :tag => "v5.0.0"
+      gem "rails", git: "https://github.com/rails/rails.git", tag: "v5.0.0"
 
-      gem "rails", :git => "https://github.com/rails/rails.git", :ref => "4aded"
+      gem "rails", git: "https://github.com/rails/rails.git", ref: "4aded"
 
   * `submodules`:
     For reference, a [git submodule](https://git-scm.com/book/en/v2/Git-Tools-Submodules)
     lets you have another git repository within a subfolder of your repository.
-    Specify `:submodules => true` to cause bundler to expand any
+    Specify `submodules: true` to cause bundler to expand any
     submodules included in the git repository
 
 If a git repository contains multiple `.gemspecs`, each `.gemspec`
@@ -346,11 +362,11 @@ as an argument, and a block which receives a single argument and interpolates it
 string to return the full repo address:
 
     git_source(:stash){ |repo_name| "https://stash.corp.acme.pl/#{repo_name}.git" }
-    gem 'rails', :stash => 'forks/rails'
+    gem 'rails', stash: 'forks/rails'
 
 In addition, if you wish to choose a specific branch:
 
-    gem "rails", :stash => "forks/rails", :branch => "branch_name"
+    gem "rails", stash: "forks/rails", branch: "branch_name"
 
 ### GITHUB
 
@@ -363,33 +379,33 @@ If the git repository you want to use is hosted on GitHub and is public, you can
 trailing ".git"), separated by a slash. If both the username and repository name are the
 same, you can omit one.
 
-    gem "rails", :github => "rails/rails"
-    gem "rails", :github => "rails"
+    gem "rails", github: "rails/rails"
+    gem "rails", github: "rails"
 
 Are both equivalent to
 
-    gem "rails", :git => "git://github.com/rails/rails.git"
+    gem "rails", git: "https://github.com/rails/rails.git"
 
 Since the `github` method is a specialization of `git_source`, it accepts a `:branch` named argument.
 
 You can also directly pass a pull request URL:
 
-    gem "rails", :github => "https://github.com/rails/rails/pull/43753"
+    gem "rails", github: "https://github.com/rails/rails/pull/43753"
 
 Which is equivalent to:
 
-    gem "rails", :github => "rails/rails", branch: "refs/pull/43753/head"
+    gem "rails", github: "rails/rails", branch: "refs/pull/43753/head"
 
 ### GIST
 
 If the git repository you want to use is hosted as a GitHub Gist and is public, you can use
 the :gist shorthand to specify the gist identifier (without the trailing ".git").
 
-    gem "the_hatch", :gist => "4815162342"
+    gem "the_hatch", gist: "4815162342"
 
 Is equivalent to:
 
-    gem "the_hatch", :git => "https://gist.github.com/4815162342.git"
+    gem "the_hatch", git: "https://gist.github.com/4815162342.git"
 
 Since the `gist` method is a specialization of `git_source`, it accepts a `:branch` named argument.
 
@@ -400,12 +416,12 @@ If the git repository you want to use is hosted on Bitbucket and is public, you
 trailing ".git"), separated by a slash. If both the username and repository name are the
 same, you can omit one.
 
-    gem "rails", :bitbucket => "rails/rails"
-    gem "rails", :bitbucket => "rails"
+    gem "rails", bitbucket: "rails/rails"
+    gem "rails", bitbucket: "rails"
 
 Are both equivalent to
 
-    gem "rails", :git => "https://rails@bitbucket.org/rails/rails.git"
+    gem "rails", git: "https://rails@bitbucket.org/rails/rails.git"
 
 Since the `bitbucket` method is a specialization of `git_source`, it accepts a `:branch` named argument.
 
@@ -423,7 +439,7 @@ version that bundler should use.
 Unlike `:git`, bundler does not compile C extensions for
 gems specified as paths.
 
-    gem "rails", :path => "vendor/rails"
+    gem "rails", path: "vendor/rails"
 
 If you would like to use multiple local gems directly from the filesystem, you can set a global `path` option to the path containing the gem's files. This will automatically load gemspec files from subdirectories.
 
@@ -452,7 +468,7 @@ applied to a group of gems by using block form.
       gem "sqlite3"
     end
 
-    group :development, :optional => true do
+    group :development, optional: true do
       gem "wirble"
       gem "faker"
     end
@@ -495,15 +511,15 @@ the `.gemspec` file.
 
 The `gemspec` method adds any runtime dependencies as gem requirements in the
 default group. It also adds development dependencies as gem requirements in the
-`development` group. Finally, it adds a gem requirement on your project (`:path
-=> '.'`). In conjunction with `Bundler.setup`, this allows you to require project
+`development` group. Finally, it adds a gem requirement on your project (`path:
+'.'`). In conjunction with `Bundler.setup`, this allows you to require project
 files in your test code as you would if the project were installed as a gem; you
 need not manipulate the load path manually or require project files via relative
 paths.
 
 The `gemspec` method supports optional `:path`, `:glob`, `:name`, and `:development_group`
 options, which control where bundler looks for the `.gemspec`, the glob it uses to look
-for the gemspec (defaults to: "{,*,*/*}.gemspec"), what named `.gemspec` it uses
+for the gemspec (defaults to: `{,*,*/*}.gemspec`), what named `.gemspec` it uses
 (if more than one is present), and which group development dependencies are included in.
 
 When a `gemspec` dependency encounters version conflicts during resolution, the
@@ -521,5 +537,7 @@ bundler uses the following priority order:
      repository declared on the parent. This results in bundler prioritizing the
      ActiveSupport gem from the Rails git repository over ones from
      `rubygems.org`
-  3. The sources specified via global `source` lines, searching each source in
-     your `Gemfile` from last added to first added.
+  3. If neither of the above conditions are met, the global source will be used.
+     If multiple global sources are specified, they will be prioritized from
+     last to first, but this is deprecated since Bundler 1.13, so Bundler prints
+     a warning and will abort with an error in the future.
diff --git a/lib/bundler/man/index.txt b/lib/bundler/man/index.txt
index ef2956b2f9..24f7633e66 100644
--- a/lib/bundler/man/index.txt
+++ b/lib/bundler/man/index.txt
@@ -6,9 +6,11 @@ bundle-cache(1)       bundle-cache.1
 bundle-check(1)       bundle-check.1
 bundle-clean(1)       bundle-clean.1
 bundle-config(1)      bundle-config.1
+bundle-console(1)     bundle-console.1
 bundle-doctor(1)      bundle-doctor.1
 bundle-exec(1)        bundle-exec.1
 bundle-gem(1)         bundle-gem.1
+bundle-help(1)        bundle-help.1
 bundle-info(1)        bundle-info.1
 bundle-init(1)        bundle-init.1
 bundle-inject(1)      bundle-inject.1
@@ -18,8 +20,10 @@ bundle-lock(1)        bundle-lock.1
 bundle-open(1)        bundle-open.1
 bundle-outdated(1)    bundle-outdated.1
 bundle-platform(1)    bundle-platform.1
+bundle-plugin(1)      bundle-plugin.1
 bundle-pristine(1)    bundle-pristine.1
 bundle-remove(1)      bundle-remove.1
 bundle-show(1)        bundle-show.1
 bundle-update(1)      bundle-update.1
+bundle-version(1)     bundle-version.1
 bundle-viz(1)         bundle-viz.1
diff --git a/lib/bundler/match_metadata.rb b/lib/bundler/match_metadata.rb
new file mode 100644
index 0000000000..499036ca93
--- /dev/null
+++ b/lib/bundler/match_metadata.rb
@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+module Bundler
+  module MatchMetadata
+    def matches_current_ruby?
+      @required_ruby_version.satisfied_by?(Gem.ruby_version)
+    end
+
+    def matches_current_rubygems?
+      @required_rubygems_version.satisfied_by?(Gem.rubygems_version)
+    end
+  end
+end
diff --git a/lib/bundler/match_platform.rb b/lib/bundler/match_platform.rb
index 69074925a6..7f7e8227f9 100644
--- a/lib/bundler/match_platform.rb
+++ b/lib/bundler/match_platform.rb
@@ -15,7 +15,6 @@ module Bundler
       return true if Gem::Platform::RUBY == gemspec_platform
       return true if local_platform == gemspec_platform
       gemspec_platform = Gem::Platform.new(gemspec_platform)
-      return true if GemHelpers.generic(gemspec_platform) === local_platform
       return true if gemspec_platform === local_platform
 
       false
diff --git a/lib/bundler/match_remote_metadata.rb b/lib/bundler/match_remote_metadata.rb
new file mode 100644
index 0000000000..5e46d52441
--- /dev/null
+++ b/lib/bundler/match_remote_metadata.rb
@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+module Bundler
+  module FetchMetadata
+    # A fallback is included because the original version of the specification
+    # API didn't include that field, so some marshalled specs in the index have it
+    # set to +nil+.
+    def matches_current_ruby?
+      @required_ruby_version ||= _remote_specification.required_ruby_version || Gem::Requirement.default
+
+      super
+    end
+
+    def matches_current_rubygems?
+      # A fallback is included because the original version of the specification
+      # API didn't include that field, so some marshalled specs in the index have it
+      # set to +nil+.
+      @required_rubygems_version ||= _remote_specification.required_rubygems_version || Gem::Requirement.default
+
+      super
+    end
+  end
+
+  module MatchRemoteMetadata
+    include MatchMetadata
+
+    prepend FetchMetadata
+  end
+end
diff --git a/lib/bundler/mirror.rb b/lib/bundler/mirror.rb
index a63b45b47d..9d437a0951 100644
--- a/lib/bundler/mirror.rb
+++ b/lib/bundler/mirror.rb
@@ -148,13 +148,11 @@ module Bundler
     class TCPSocketProbe
       def replies?(mirror)
         MirrorSockets.new(mirror).any? do |socket, address, timeout|
-          begin
-            socket.connect_nonblock(address)
-          rescue Errno::EINPROGRESS
-            wait_for_writtable_socket(socket, address, timeout)
-          rescue RuntimeError # Connection failed somehow, again
-            false
-          end
+          socket.connect_nonblock(address)
+        rescue Errno::EINPROGRESS
+          wait_for_writtable_socket(socket, address, timeout)
+        rescue RuntimeError # Connection failed somehow, again
+          false
         end
       end
 
diff --git a/lib/bundler/plugin.rb b/lib/bundler/plugin.rb
index 158c69e1a1..f3caff8963 100644
--- a/lib/bundler/plugin.rb
+++ b/lib/bundler/plugin.rb
@@ -15,7 +15,7 @@ module Bundler
     class UnknownSourceError < PluginError; end
     class PluginInstallError < PluginError; end
 
-    PLUGIN_FILE_NAME = "plugins.rb".freeze
+    PLUGIN_FILE_NAME = "plugins.rb"
 
     module_function
 
@@ -36,6 +36,8 @@ module Bundler
     # @param [Hash] options various parameters as described in description.
     #               Refer to cli/plugin for available options
     def install(names, options)
+      raise InvalidOption, "You cannot specify `--branch` and `--ref` at the same time." if options["branch"] && options["ref"]
+
       specs = Installer.new.install(names, options)
 
       save_plugins names, specs
diff --git a/lib/bundler/plugin/api/source.rb b/lib/bundler/plugin/api/source.rb
index 32b1d0ee38..67c45bd204 100644
--- a/lib/bundler/plugin/api/source.rb
+++ b/lib/bundler/plugin/api/source.rb
@@ -258,7 +258,7 @@ module Bundler
           @dependencies |= Array(names)
         end
 
-        # Note: Do not override if you don't know what you are doing.
+        # NOTE: Do not override if you don't know what you are doing.
         def can_lock?(spec)
           spec.source == self
         end
@@ -285,7 +285,7 @@ module Bundler
         end
         alias_method :identifier, :to_s
 
-        # Note: Do not override if you don't know what you are doing.
+        # NOTE: Do not override if you don't know what you are doing.
         def include?(other)
           other == self
         end
@@ -294,7 +294,7 @@ module Bundler
           SharedHelpers.digest(:SHA1).hexdigest(uri)
         end
 
-        # Note: Do not override if you don't know what you are doing.
+        # NOTE: Do not override if you don't know what you are doing.
         def gem_install_dir
           Bundler.install_path
         end
@@ -309,12 +309,6 @@ module Bundler
         end
 
         # @private
-        # Returns true
-        def bundler_plugin_api_source?
-          true
-        end
-
-        # @private
         # This API on source might not be stable, and for now we expect plugins
         # to download all specs in `#specs`, so we implement the method for
         # compatibility purposes and leave it undocumented (and don't support)
diff --git a/lib/bundler/plugin/index.rb b/lib/bundler/plugin/index.rb
index 29d33be718..a2d5eaa38a 100644
--- a/lib/bundler/plugin/index.rb
+++ b/lib/bundler/plugin/index.rb
@@ -146,7 +146,7 @@ module Bundler
       # @param [Boolean] is the index file global index
       def load_index(index_file, global = false)
         SharedHelpers.filesystem_access(index_file, :read) do |index_f|
-          valid_file = index_f && index_f.exist? && !index_f.size.zero?
+          valid_file = index_f&.exist? && !index_f.size.zero?
           break unless valid_file
 
           data = index_f.read
@@ -167,11 +167,11 @@ module Bundler
       # to be only String key value pairs)
       def save_index
         index = {
-          "commands"     => @commands,
-          "hooks"        => @hooks,
-          "load_paths"   => @load_paths,
+          "commands" => @commands,
+          "hooks" => @hooks,
+          "load_paths" => @load_paths,
           "plugin_paths" => @plugin_paths,
-          "sources"      => @sources,
+          "sources" => @sources,
         }
 
         require_relative "../yaml_serializer"
diff --git a/lib/bundler/plugin/installer.rb b/lib/bundler/plugin/installer.rb
index 81ecafa470..c9ff12ce4b 100644
--- a/lib/bundler/plugin/installer.rb
+++ b/lib/bundler/plugin/installer.rb
@@ -83,8 +83,11 @@ module Bundler
 
         Bundler.configure_gem_home_and_path(Plugin.root)
 
-        definition = Definition.new(nil, deps, source_list, true)
-        install_definition(definition)
+        Bundler.settings.temporary(:deployment => false, :frozen => false) do
+          definition = Definition.new(nil, deps, source_list, true)
+
+          install_definition(definition)
+        end
       end
 
       # Installs the plugins and deps from the provided specs and returns map of
diff --git a/lib/bundler/plugin/installer/git.rb b/lib/bundler/plugin/installer/git.rb
index fbb6c5e40e..deec5e99b3 100644
--- a/lib/bundler/plugin/installer/git.rb
+++ b/lib/bundler/plugin/installer/git.rb
@@ -20,10 +20,6 @@ module Bundler
           end
         end
 
-        def version_message(spec)
-          "#{spec.name} #{spec.version}"
-        end
-
         def root
           Plugin.root
         end
diff --git a/lib/bundler/plugin/installer/rubygems.rb b/lib/bundler/plugin/installer/rubygems.rb
index e144c14b24..cb5db9c30e 100644
--- a/lib/bundler/plugin/installer/rubygems.rb
+++ b/lib/bundler/plugin/installer/rubygems.rb
@@ -4,16 +4,8 @@ module Bundler
   module Plugin
     class Installer
       class Rubygems < Bundler::Source::Rubygems
-        def version_message(spec)
-          "#{spec.name} #{spec.version}"
-        end
-
         private
 
-        def requires_sudo?
-          false # Will change on implementation of project level plugins
-        end
-
         def rubygems_dir
           Plugin.root
         end
diff --git a/lib/bundler/process_lock.rb b/lib/bundler/process_lock.rb
index a5cc614e20..0297f80e2c 100644
--- a/lib/bundler/process_lock.rb
+++ b/lib/bundler/process_lock.rb
@@ -12,7 +12,7 @@ module Bundler
         yield
         f.flock(File::LOCK_UN)
       end
-    rescue Errno::EACCES, Errno::ENOLCK, Errno::ENOTSUP
+    rescue Errno::EACCES, Errno::ENOLCK, Errno::ENOTSUP, Errno::EPERM, Errno::EROFS
       # In the case the user does not have access to
       # create the lock file or is using NFS where
       # locks are not available we skip locking.
diff --git a/lib/bundler/remote_specification.rb b/lib/bundler/remote_specification.rb
index 4e966b820a..f626a3218e 100644
--- a/lib/bundler/remote_specification.rb
+++ b/lib/bundler/remote_specification.rb
@@ -6,6 +6,7 @@ module Bundler
   # be seeded with what we're given from the source's abbreviated index - the
   # full specification will only be fetched when necessary.
   class RemoteSpecification
+    include MatchRemoteMetadata
     include MatchPlatform
     include Comparable
 
@@ -16,7 +17,8 @@ module Bundler
     def initialize(name, version, platform, spec_fetcher)
       @name         = name
       @version      = Gem::Version.create version
-      @platform     = platform
+      @original_platform = platform || Gem::Platform::RUBY
+      @platform     = Gem::Platform.new(platform)
       @spec_fetcher = spec_fetcher
       @dependencies = nil
     end
@@ -27,18 +29,11 @@ module Bundler
       @platform = _remote_specification.platform
     end
 
-    # A fallback is included because the original version of the specification
-    # API didn't include that field, so some marshalled specs in the index have it
-    # set to +nil+.
-    def required_rubygems_version
-      @required_rubygems_version ||= _remote_specification.required_rubygems_version || Gem::Requirement.default
-    end
-
     def full_name
-      if platform == Gem::Platform::RUBY || platform.nil?
+      @full_name ||= if @platform == Gem::Platform::RUBY
         "#{@name}-#{@version}"
       else
-        "#{@name}-#{@version}-#{platform}"
+        "#{@name}-#{@version}-#{@platform}"
       end
     end
 
@@ -105,9 +100,9 @@ module Bundler
     end
 
     def _remote_specification
-      @_remote_specification ||= @spec_fetcher.fetch_spec([@name, @version, @platform])
+      @_remote_specification ||= @spec_fetcher.fetch_spec([@name, @version, @original_platform])
       @_remote_specification || raise(GemspecError, "Gemspec data for #{full_name} was" \
-        " missing from the server! Try installing with `--full-index` as a workaround.")
+        " missing from the server!")
     end
 
     def method_missing(method, *args, &blk)
diff --git a/lib/bundler/resolver.rb b/lib/bundler/resolver.rb
index be0751d9d2..2ad35bc931 100644
--- a/lib/bundler/resolver.rb
+++ b/lib/bundler/resolver.rb
@@ -1,387 +1,427 @@
 # frozen_string_literal: true
 
 module Bundler
+  #
+  # This class implements the interface needed by PubGrub for resolution. It is
+  # equivalent to the `PubGrub::BasicPackageSource` class provided by PubGrub by
+  # default and used by the most simple PubGrub consumers.
+  #
   class Resolver
-    require_relative "vendored_molinillo"
-    require_relative "resolver/spec_group"
+    require_relative "vendored_pub_grub"
+    require_relative "resolver/base"
+    require_relative "resolver/candidate"
+    require_relative "resolver/incompatibility"
+    require_relative "resolver/root"
 
     include GemHelpers
 
-    # Figures out the best possible configuration of gems that satisfies
-    # the list of passed dependencies and any child dependencies without
-    # causing any gem activation errors.
-    #
-    # ==== Parameters
-    # *dependencies<Gem::Dependency>:: The list of dependencies to resolve
-    #
-    # ==== Returns
-    # <GemBundle>,nil:: If the list of dependencies can be resolved, a
-    #   collection of gemspecs is returned. Otherwise, nil is returned.
-    def self.resolve(requirements, source_requirements = {}, base = [], gem_version_promoter = GemVersionPromoter.new, additional_base_requirements = [], platforms = nil)
-      base = SpecSet.new(base) unless base.is_a?(SpecSet)
-      resolver = new(source_requirements, base, gem_version_promoter, additional_base_requirements, platforms)
-      result = resolver.start(requirements)
-      SpecSet.new(SpecSet.new(result).for(requirements.reject{|dep| dep.name.end_with?("\0") }))
-    end
-
-    def initialize(source_requirements, base, gem_version_promoter, additional_base_requirements, platforms)
-      @source_requirements = source_requirements
+    def initialize(base, gem_version_promoter)
+      @source_requirements = base.source_requirements
       @base = base
-      @resolver = Molinillo::Resolver.new(self, self)
-      @search_for = {}
-      @base_dg = Molinillo::DependencyGraph.new
-      @base.each do |ls|
-        dep = Dependency.new(ls.name, ls.version)
-        @base_dg.add_vertex(ls.name, DepProxy.get_proxy(dep, ls.platform), true)
-      end
-      additional_base_requirements.each {|d| @base_dg.add_vertex(d.name, d) }
-      @platforms = platforms.reject {|p| p != Gem::Platform::RUBY && (platforms - [p]).any? {|pl| generic(pl) == p } }
-      @resolving_only_for_ruby = platforms == [Gem::Platform::RUBY]
       @gem_version_promoter = gem_version_promoter
-      @use_gvp = Bundler.feature_flag.use_gem_version_promoter_for_major_updates? || !@gem_version_promoter.major?
     end
 
-    def start(requirements)
-      @gem_version_promoter.prerelease_specified = @prerelease_specified = {}
-      requirements.each {|dep| @prerelease_specified[dep.name] ||= dep.prerelease? }
-
-      verify_gemfile_dependencies_are_found!(requirements)
-      dg = @resolver.resolve(requirements, @base_dg)
-      dg.
-        map(&:payload).
-        reject {|sg| sg.name.end_with?("\0") }.
-        map(&:to_specs).
-        flatten
-    rescue Molinillo::VersionConflict => e
-      message = version_conflict_message(e)
-      raise VersionConflict.new(e.conflicts.keys.uniq, message)
-    rescue Molinillo::CircularDependencyError => e
-      names = e.dependencies.sort_by(&:name).map {|d| "gem '#{d.name}'" }
-      raise CyclicDependencyError, "Your bundle requires gems that depend" \
-        " on each other, creating an infinite loop. Please remove" \
-        " #{names.count > 1 ? "either " : ""}#{names.join(" or ")}" \
-        " and try again."
-    end
+    def start
+      @requirements = @base.requirements
+      @packages = @base.packages
 
-    include Molinillo::UI
-
-    # Conveys debug information to the user.
-    #
-    # @param [Integer] depth the current depth of the resolution process.
-    # @return [void]
-    def debug(depth = 0)
-      return unless debug?
-      debug_info = yield
-      debug_info = debug_info.inspect unless debug_info.is_a?(String)
-      puts debug_info.split("\n").map {|s| depth == 0 ? "BUNDLER: #{s}" : "BUNDLER(#{depth}): #{s}" }
-    end
+      root, logger = setup_solver
 
-    def debug?
-      return @debug_mode if defined?(@debug_mode)
-      @debug_mode =
-        ENV["BUNDLER_DEBUG_RESOLVER"] ||
-        ENV["BUNDLER_DEBUG_RESOLVER_TREE"] ||
-        ENV["DEBUG_RESOLVER"] ||
-        ENV["DEBUG_RESOLVER_TREE"] ||
-        false
-    end
+      Bundler.ui.info "Resolving dependencies...", true
 
-    def before_resolution
-      Bundler.ui.info "Resolving dependencies...", debug?
+      solve_versions(:root => root, :logger => logger)
     end
 
-    def after_resolution
-      Bundler.ui.info ""
-    end
+    def setup_solver
+      root = Resolver::Root.new(name_for_explicit_dependency_source)
+      root_version = Resolver::Candidate.new(0)
 
-    def indicate_progress
-      Bundler.ui.info ".", false unless debug?
-    end
+      @all_specs = Hash.new do |specs, name|
+        specs[name] = source_for(name).specs.search(name).reject do |s|
+          s.dependencies.any? {|d| d.name == name && !d.requirement.satisfied_by?(s.version) } # ignore versions that depend on themselves incorrectly
+        end.sort_by {|s| [s.version, s.platform.to_s] }
+      end
+
+      @sorted_versions = Hash.new do |candidates, package|
+        candidates[package] = if package.root?
+          [root_version]
+        else
+          all_versions_for(package).sort
+        end
+      end
 
-    include Molinillo::SpecificationProvider
+      root_dependencies = prepare_dependencies(@requirements, @packages)
 
-    def dependencies_for(specification)
-      specification.dependencies_for_activated_platforms
+      @cached_dependencies = Hash.new do |dependencies, package|
+        dependencies[package] = if package.root?
+          { root_version => root_dependencies }
+        else
+          Hash.new do |versions, version|
+            versions[version] = to_dependency_hash(version.dependencies.reject {|d| d.name == package.name }, @packages)
+          end
+        end
+      end
+
+      logger = Bundler::UI::Shell.new
+      logger.level = debug? ? "debug" : "warn"
+
+      [root, logger]
     end
 
-    def search_for(dependency_proxy)
-      platform = dependency_proxy.__platform
-      dependency = dependency_proxy.dep
-      name = dependency.name
-      @search_for[dependency_proxy] ||= begin
-        results = results_for(dependency, @base[name])
+    def solve_versions(root:, logger:)
+      solver = PubGrub::VersionSolver.new(:source => self, :root => root, :logger => logger)
+      result = solver.solve
+      result.map {|package, version| version.to_specs(package) }.flatten.uniq
+    rescue PubGrub::SolveFailure => e
+      incompatibility = e.incompatibility
+
+      names_to_unlock, names_to_allow_prereleases_for, extended_explanation = find_names_to_relax(incompatibility)
+
+      names_to_relax = names_to_unlock + names_to_allow_prereleases_for
+
+      if names_to_relax.any?
+        if names_to_unlock.any?
+          Bundler.ui.debug "Found conflicts with locked dependencies. Will retry with #{names_to_unlock.join(", ")} unlocked...", true
 
-        if vertex = @base_dg.vertex_named(name)
-          locked_requirement = vertex.payload.requirement
+          @base.unlock_names(names_to_unlock)
         end
 
-        if !@prerelease_specified[name] && (!@use_gvp || locked_requirement.nil?)
-          # Move prereleases to the beginning of the list, so they're considered
-          # last during resolution.
-          pre, results = results.partition {|spec| spec.version.prerelease? }
-          results = pre + results
+        if names_to_allow_prereleases_for.any?
+          Bundler.ui.debug "Found conflicts with dependencies with prereleases. Will retrying considering prereleases for #{names_to_allow_prereleases_for.join(", ")}...", true
+
+          @base.include_prereleases(names_to_allow_prereleases_for)
         end
 
-        spec_groups = if results.any?
-          nested = []
-          results.each do |spec|
-            version, specs = nested.last
-            if version == spec.version
-              specs << spec
-            else
-              nested << [spec.version, [spec]]
-            end
-          end
-          nested.reduce([]) do |groups, (version, specs)|
-            next groups if locked_requirement && !locked_requirement.satisfied_by?(version)
-            next groups unless specs.any? {|spec| spec.match_platform(platform) }
+        root, logger = setup_solver
 
-            specs_by_platform = Hash.new do |current_specs, current_platform|
-              current_specs[current_platform] = select_best_platform_match(specs, current_platform)
-            end
+        Bundler.ui.debug "Retrying resolution...", true
+        retry
+      end
 
-            spec_group_ruby = SpecGroup.create_for(specs_by_platform, [Gem::Platform::RUBY], Gem::Platform::RUBY)
-            groups << spec_group_ruby if spec_group_ruby
+      explanation = e.message
 
-            next groups if @resolving_only_for_ruby
+      if extended_explanation
+        explanation << "\n\n"
+        explanation << extended_explanation
+      end
 
-            spec_group = SpecGroup.create_for(specs_by_platform, @platforms, platform)
-            groups << spec_group
+      raise SolveFailure.new(explanation)
+    end
 
-            groups
+    def find_names_to_relax(incompatibility)
+      names_to_unlock = []
+      names_to_allow_prereleases_for = []
+      extended_explanation = nil
+
+      while incompatibility.conflict?
+        cause = incompatibility.cause
+        incompatibility = cause.incompatibility
+
+        incompatibility.terms.each do |term|
+          package = term.package
+          name = package.name
+
+          if base_requirements[name]
+            names_to_unlock << name
+          elsif package.ignores_prereleases?
+            names_to_allow_prereleases_for << name
           end
-        else
-          []
-        end
-        # GVP handles major itself, but it's still a bit risky to trust it with it
-        # until we get it settled with new behavior. For 2.x it can take over all cases.
-        if !@use_gvp
-          spec_groups
-        else
-          @gem_version_promoter.sort_versions(dependency, spec_groups)
+
+          no_versions_incompat = [cause.incompatibility, cause.satisfier].find {|incompat| incompat.cause.is_a?(PubGrub::Incompatibility::NoVersions) }
+          next unless no_versions_incompat
+
+          extended_explanation = no_versions_incompat.extended_explanation
         end
       end
-    end
 
-    def index_for(dependency)
-      source_for(dependency.name).specs
+      [names_to_unlock.uniq, names_to_allow_prereleases_for.uniq, extended_explanation]
     end
 
-    def source_for(name)
-      @source_requirements[name] || @source_requirements[:default]
-    end
+    def parse_dependency(package, dependency)
+      range = if repository_for(package).is_a?(Source::Gemspec)
+        PubGrub::VersionRange.any
+      else
+        requirement_to_range(dependency)
+      end
 
-    def results_for(dependency, base)
-      index_for(dependency).search(dependency, base)
+      PubGrub::VersionConstraint.new(package, :range => range)
     end
 
-    def name_for(dependency)
-      dependency.name
-    end
+    def versions_for(package, range=VersionRange.any)
+      versions = range.select_versions(@sorted_versions[package])
 
-    def name_for_explicit_dependency_source
-      Bundler.default_gemfile.basename.to_s
-    rescue StandardError
-      "Gemfile"
+      sort_versions(package, versions)
     end
 
-    def name_for_locking_dependency_source
-      Bundler.default_lockfile.basename.to_s
-    rescue StandardError
-      "Gemfile.lock"
-    end
+    def no_versions_incompatibility_for(package, unsatisfied_term)
+      cause = PubGrub::Incompatibility::NoVersions.new(unsatisfied_term)
+      name = package.name
+      constraint = unsatisfied_term.constraint
+      constraint_string = constraint.constraint_string
+      requirements = constraint_string.split(" OR ").map {|req| Gem::Requirement.new(req.split(",")) }
 
-    def requirement_satisfied_by?(requirement, activated, spec)
-      requirement.matches_spec?(spec) || spec.source.is_a?(Source::Gemspec)
-    end
+      if name == "bundler" && bundler_pinned_to_current_version?
+        custom_explanation = "the current Bundler version (#{Bundler::VERSION}) does not satisfy #{constraint}"
+        extended_explanation = bundler_not_found_message(requirements)
+      else
+        specs_matching_other_platforms = filter_matching_specs(@all_specs[name], requirements)
 
-    def dependencies_equal?(dependencies, other_dependencies)
-      dependencies.map(&:dep) == other_dependencies.map(&:dep)
-    end
+        platforms_explanation = specs_matching_other_platforms.any? ? " for any resolution platforms (#{package.platforms.join(", ")})" : ""
+        custom_explanation = "#{constraint} could not be found in #{repository_for(package)}#{platforms_explanation}"
 
-    def sort_dependencies(dependencies, activated, conflicts)
-      dependencies.sort_by do |dependency|
-        name = name_for(dependency)
-        vertex = activated.vertex_named(name)
-        [
-          @base_dg.vertex_named(name) ? 0 : 1,
-          vertex.payload ? 0 : 1,
-          vertex.root? ? 0 : 1,
-          amount_constrained(dependency),
-          conflicts[name] ? 0 : 1,
-          vertex.payload ? 0 : search_for(dependency).count,
-          self.class.platform_sort_key(dependency.__platform),
-        ]
+        label = "#{name} (#{constraint_string})"
+        extended_explanation = other_specs_matching_message(specs_matching_other_platforms, label) if specs_matching_other_platforms.any?
       end
+
+      Incompatibility.new([unsatisfied_term], :cause => cause, :custom_explanation => custom_explanation, :extended_explanation => extended_explanation)
     end
 
-    def self.platform_sort_key(platform)
-      # Prefer specific platform to not specific platform
-      return ["99-LAST", "", "", ""] if Gem::Platform::RUBY == platform
-      ["00", *platform.to_a.map {|part| part || "" }]
+    def debug?
+      ENV["BUNDLER_DEBUG_RESOLVER"] ||
+        ENV["BUNDLER_DEBUG_RESOLVER_TREE"] ||
+        ENV["DEBUG_RESOLVER"] ||
+        ENV["DEBUG_RESOLVER_TREE"] ||
+        false
     end
 
-    private
+    def incompatibilities_for(package, version)
+      package_deps = @cached_dependencies[package]
+      sorted_versions = @sorted_versions[package]
+      package_deps[version].map do |dep_package, dep_constraint|
+        low = high = sorted_versions.index(version)
 
-    # returns an integer \in (-\infty, 0]
-    # a number closer to 0 means the dependency is less constraining
-    #
-    # dependencies w/ 0 or 1 possibilities (ignoring version requirements)
-    # are given very negative values, so they _always_ sort first,
-    # before dependencies that are unconstrained
-    def amount_constrained(dependency)
-      @amount_constrained ||= {}
-      @amount_constrained[dependency.name] ||= begin
-        if (base = @base[dependency.name]) && !base.empty?
-          dependency.requirement.satisfied_by?(base.first.version) ? 0 : 1
-        else
-          all = index_for(dependency).search(dependency.name).size
+        # find version low such that all >= low share the same dep
+        while low > 0 && package_deps[sorted_versions[low - 1]][dep_package] == dep_constraint
+          low -= 1
+        end
+        low =
+          if low == 0
+            nil
+          else
+            sorted_versions[low]
+          end
 
-          if all <= 1
-            all - 1_000_000
+        # find version high such that all < high share the same dep
+        while high < sorted_versions.length && package_deps[sorted_versions[high]][dep_package] == dep_constraint
+          high += 1
+        end
+        high =
+          if high == sorted_versions.length
+            nil
           else
-            search = search_for(dependency)
-            search = @prerelease_specified[dependency.name] ? search.count : search.count {|s| !s.version.prerelease? }
-            search - all
+            sorted_versions[high]
           end
+
+        range = PubGrub::VersionRange.new(:min => low, :max => high, :include_min => true)
+
+        self_constraint = PubGrub::VersionConstraint.new(package, :range => range)
+
+        dep_term = PubGrub::Term.new(dep_constraint, false)
+        self_term = PubGrub::Term.new(self_constraint, true)
+
+        custom_explanation = if dep_package.meta? && package.root?
+          "current #{dep_package} version is #{dep_constraint.constraint_string}"
         end
+
+        PubGrub::Incompatibility.new([self_term, dep_term], :cause => :dependency, :custom_explanation => custom_explanation)
       end
     end
 
-    def verify_gemfile_dependencies_are_found!(requirements)
-      requirements.map! do |requirement|
-        name = requirement.name
-        next requirement if name == "bundler"
-        next requirement unless search_for(requirement).empty?
-        next unless requirement.current_platform?
-
-        if (base = @base[name]) && !base.empty?
-          version = base.first.version
-          message = "You have requested:\n" \
-            "  #{name} #{requirement.requirement}\n\n" \
-            "The bundle currently has #{name} locked at #{version}.\n" \
-            "Try running `bundle update #{name}`\n\n" \
-            "If you are updating multiple gems in your Gemfile at once,\n" \
-            "try passing them all to `bundle update`"
-        else
-          message = gem_not_found_message(name, requirement, source_for(name))
-        end
-        raise GemNotFound, message
-      end.compact!
+    def all_versions_for(package)
+      name = package.name
+      results = (@base[name] + filter_prereleases(@all_specs[name], package)).uniq {|spec| [spec.version.hash, spec.platform] }
+
+      if name == "bundler" && !bundler_pinned_to_current_version?
+        bundler_spec = Gem.loaded_specs["bundler"]
+        results << bundler_spec if bundler_spec
+      end
+
+      locked_requirement = base_requirements[name]
+      results = filter_matching_specs(results, locked_requirement) if locked_requirement
+
+      versions = results.group_by(&:version).reduce([]) do |groups, (version, specs)|
+        platform_specs = package.platforms.flat_map {|platform| select_best_platform_match(specs, platform) }
+        next groups if platform_specs.empty?
+
+        ruby_specs = select_best_platform_match(specs, Gem::Platform::RUBY)
+        groups << Resolver::Candidate.new(version, :specs => ruby_specs) if ruby_specs.any?
+
+        next groups if platform_specs == ruby_specs || package.force_ruby_platform?
+
+        groups << Resolver::Candidate.new(version, :specs => platform_specs)
+
+        groups
+      end
+
+      sort_versions(package, versions)
+    end
+
+    def source_for(name)
+      @source_requirements[name] || @source_requirements[:default]
     end
 
-    def gem_not_found_message(name, requirement, source, extra_message = "")
-      specs = source.specs.search(name)
+    def default_bundler_source
+      @source_requirements[:default_bundler]
+    end
+
+    def bundler_pinned_to_current_version?
+      !default_bundler_source.nil?
+    end
+
+    def name_for_explicit_dependency_source
+      Bundler.default_gemfile.basename.to_s
+    rescue StandardError
+      "Gemfile"
+    end
+
+    def raise_not_found!(package)
+      name = package.name
+      source = source_for(name)
+      specs = @all_specs[name]
       matching_part = name
-      requirement_label = SharedHelpers.pretty_dependency(requirement)
+      requirement_label = SharedHelpers.pretty_dependency(package.dependency)
       cache_message = begin
                           " or in gems cached in #{Bundler.settings.app_cache_path}" if Bundler.app_cache.exist?
                         rescue GemfileNotFound
                           nil
                         end
-      specs_matching_requirement = specs.select {| spec| requirement.matches_spec?(spec) }
+      specs_matching_requirement = filter_matching_specs(specs, package.dependency.requirement)
 
       if specs_matching_requirement.any?
         specs = specs_matching_requirement
         matching_part = requirement_label
-        requirement_label = "#{requirement_label} #{requirement.__platform}"
+        platforms = package.platforms
+        platform_label = platforms.size == 1 ? "platform '#{platforms.first}" : "platforms '#{platforms.join("', '")}"
+        requirement_label = "#{requirement_label}' with #{platform_label}"
       end
 
-      message = String.new("Could not find gem '#{requirement_label}'#{extra_message} in #{source}#{cache_message}.\n")
+      message = String.new("Could not find gem '#{requirement_label}' in #{source}#{cache_message}.\n")
 
       if specs.any?
-        message << "\nThe source contains the following gems matching '#{matching_part}':\n"
-        message << specs.map {|s| "  * #{s.full_name}" }.join("\n")
+        message << "\n#{other_specs_matching_message(specs, matching_part)}"
       end
 
-      message
+      raise GemNotFound, message
     end
 
-    def version_conflict_message(e)
-      # only show essential conflicts, if possible
-      conflicts = e.conflicts.dup
+    private
+
+    def filter_matching_specs(specs, requirements)
+      Array(requirements).flat_map do |requirement|
+        specs.select {| spec| requirement_satisfied_by?(requirement, spec) }
+      end
+    end
+
+    def filter_prereleases(specs, package)
+      return specs unless package.ignores_prereleases? && specs.size > 1
+
+      specs.reject {|s| s.version.prerelease? }
+    end
 
-      if conflicts["bundler"]
-        conflicts.replace("bundler" => conflicts["bundler"])
+    def requirement_satisfied_by?(requirement, spec)
+      requirement.satisfied_by?(spec.version) || spec.source.is_a?(Source::Gemspec)
+    end
+
+    def sort_versions(package, versions)
+      if versions.size > 1
+        @gem_version_promoter.sort_versions(package, versions).reverse
       else
-        conflicts.delete_if do |_name, conflict|
-          deps = conflict.requirement_trees.map(&:last).flatten(1)
-          !Bundler::VersionRanges.empty?(*Bundler::VersionRanges.for_many(deps.map(&:requirement)))
+        versions
+      end
+    end
+
+    def repository_for(package)
+      source_for(package.name)
+    end
+
+    def base_requirements
+      @base.base_requirements
+    end
+
+    def prepare_dependencies(requirements, packages)
+      to_dependency_hash(requirements, packages).map do |dep_package, dep_constraint|
+        name = dep_package.name
+
+        next [dep_package, dep_constraint] if name == "bundler"
+
+        versions = versions_for(dep_package, dep_constraint.range)
+        if versions.empty? && dep_package.ignores_prereleases?
+          @sorted_versions.delete(dep_package)
+          dep_package.consider_prereleases!
+          versions = versions_for(dep_package, dep_constraint.range)
+        end
+        next [dep_package, dep_constraint] unless versions.empty?
+
+        next unless dep_package.current_platform?
+
+        raise_not_found!(dep_package)
+      end.compact.to_h
+    end
+
+    def other_specs_matching_message(specs, requirement)
+      message = String.new("The source contains the following gems matching '#{requirement}':\n")
+      message << specs.map {|s| "  * #{s.full_name}" }.join("\n")
+      message
+    end
+
+    def requirement_to_range(requirement)
+      ranges = requirement.requirements.map do |(op, version)|
+        ver = Resolver::Candidate.new(version).generic!
+        platform_ver = Resolver::Candidate.new(version).platform_specific!
+
+        case op
+        when "~>"
+          name = "~> #{ver}"
+          bump = Resolver::Candidate.new(version.bump.to_s + ".A")
+          PubGrub::VersionRange.new(:name => name, :min => ver, :max => bump, :include_min => true)
+        when ">"
+          PubGrub::VersionRange.new(:min => platform_ver)
+        when ">="
+          PubGrub::VersionRange.new(:min => ver, :include_min => true)
+        when "<"
+          PubGrub::VersionRange.new(:max => ver)
+        when "<="
+          PubGrub::VersionRange.new(:max => platform_ver, :include_max => true)
+        when "="
+          PubGrub::VersionRange.new(:min => ver, :max => platform_ver, :include_min => true, :include_max => true)
+        when "!="
+          PubGrub::VersionRange.new(:min => ver, :max => platform_ver, :include_min => true, :include_max => true).invert
+        else
+          raise "bad version specifier: #{op}"
         end
       end
 
-      e = Molinillo::VersionConflict.new(conflicts, e.specification_provider) unless conflicts.empty?
-
-      solver_name = "Bundler"
-      possibility_type = "gem"
-      e.message_with_trees(
-        :solver_name => solver_name,
-        :possibility_type => possibility_type,
-        :reduce_trees => lambda do |trees|
-          # called first, because we want to reduce the amount of work required to find maximal empty sets
-          trees = trees.uniq {|t| t.flatten.map {|dep| [dep.name, dep.requirement] } }
-
-          # bail out if tree size is too big for Array#combination to make any sense
-          return trees if trees.size > 15
-          maximal = 1.upto(trees.size).map do |size|
-            trees.map(&:last).flatten(1).combination(size).to_a
-          end.flatten(1).select do |deps|
-            Bundler::VersionRanges.empty?(*Bundler::VersionRanges.for_many(deps.map(&:requirement)))
-          end.min_by(&:size)
-
-          trees.reject! {|t| !maximal.include?(t.last) } if maximal
-
-          trees.sort_by {|t| t.reverse.map(&:name) }
-        end,
-        :printable_requirement => lambda {|req| SharedHelpers.pretty_dependency(req) },
-        :additional_message_for_conflict => lambda do |o, name, conflict|
-          if name == "bundler"
-            o << %(\n  Current Bundler version:\n    bundler (#{Bundler::VERSION}))
-
-            conflict_dependency = conflict.requirement
-            conflict_requirement = conflict_dependency.requirement
-            other_bundler_required = !conflict_requirement.satisfied_by?(Gem::Version.new(Bundler::VERSION))
-
-            if other_bundler_required
-              o << "\n\n"
-
-              candidate_specs = source_for(:default_bundler).specs.search(conflict_dependency)
-              if candidate_specs.any?
-                target_version = candidate_specs.last.version
-                new_command = [File.basename($PROGRAM_NAME), "_#{target_version}_", *ARGV].join(" ")
-                o << "Your bundle requires a different version of Bundler than the one you're running.\n"
-                o << "Install the necessary version with `gem install bundler:#{target_version}` and rerun bundler using `#{new_command}`\n"
-              else
-                o << "Your bundle requires a different version of Bundler than the one you're running, and that version could not be found.\n"
-              end
-            end
-          elsif conflict.locked_requirement
-            o << "\n"
-            o << %(Running `bundle update` will rebuild your snapshot from scratch, using only\n)
-            o << %(the gems in your Gemfile, which may resolve the conflict.\n)
-          elsif !conflict.existing && !name.end_with?("\0")
-            o << "\n"
-
-            relevant_source = conflict.requirement.source || source_for(name)
-
-            extra_message = if conflict.requirement_trees.first.size > 1
-              ", which is required by gem '#{SharedHelpers.pretty_dependency(conflict.requirement_trees.first[-2])}',"
-            else
-              ""
-            end
-
-            o << gem_not_found_message(name, conflict.requirement, relevant_source, extra_message)
-          end
-        end,
-        :version_for_spec => lambda {|spec| spec.version },
-        :incompatible_version_message_for_conflict => lambda do |name, _conflict|
-          if name.end_with?("\0")
-            %(#{solver_name} found conflicting requirements for the #{name} version:)
-          else
-            %(#{solver_name} could not find compatible versions for #{possibility_type} "#{name}":)
-          end
+      ranges.inject(&:intersect)
+    end
+
+    def to_dependency_hash(dependencies, packages)
+      dependencies.inject({}) do |deps, dep|
+        package = packages[dep.name]
+
+        current_req = deps[package]
+        new_req = parse_dependency(package, dep.requirement)
+
+        deps[package] = if current_req
+          current_req.intersect(new_req)
+        else
+          new_req
         end
-      )
+
+        deps
+      end
+    end
+
+    def bundler_not_found_message(conflict_dependencies)
+      candidate_specs = filter_matching_specs(default_bundler_source.specs.search("bundler"), conflict_dependencies)
+
+      if candidate_specs.any?
+        target_version = candidate_specs.last.version
+        new_command = [File.basename($PROGRAM_NAME), "_#{target_version}_", *ARGV].join(" ")
+        "Your bundle requires a different version of Bundler than the one you're running.\n" \
+        "Install the necessary version with `gem install bundler:#{target_version}` and rerun bundler using `#{new_command}`\n"
+      else
+        "Your bundle requires a different version of Bundler than the one you're running, and that version could not be found.\n"
+      end
     end
   end
 end
diff --git a/lib/bundler/resolver/base.rb b/lib/bundler/resolver/base.rb
new file mode 100644
index 0000000000..e5c3763c3f
--- /dev/null
+++ b/lib/bundler/resolver/base.rb
@@ -0,0 +1,107 @@
+# frozen_string_literal: true
+
+require_relative "package"
+
+module Bundler
+  class Resolver
+    class Base
+      attr_reader :packages, :requirements, :source_requirements
+
+      def initialize(source_requirements, dependencies, base, platforms, options)
+        @source_requirements = source_requirements
+
+        @base = base
+
+        @packages = Hash.new do |hash, name|
+          hash[name] = Package.new(name, platforms, **options)
+        end
+
+        @requirements = dependencies.map do |dep|
+          dep_platforms = dep.gem_platforms(platforms)
+
+          # Dependencies scoped to external platforms are ignored
+          next if dep_platforms.empty?
+
+          name = dep.name
+
+          @packages[name] = Package.new(name, dep_platforms, **options.merge(:dependency => dep))
+
+          dep
+        end.compact
+      end
+
+      def [](name)
+        @base[name]
+      end
+
+      def delete(specs)
+        @base.delete(specs)
+      end
+
+      def get_package(name)
+        @packages[name]
+      end
+
+      def base_requirements
+        @base_requirements ||= build_base_requirements
+      end
+
+      def unlock_names(names)
+        indirect_pins = indirect_pins(names)
+
+        if indirect_pins.any?
+          loosen_names(indirect_pins)
+        else
+          pins = pins(names)
+
+          if pins.any?
+            loosen_names(pins)
+          else
+            unrestrict_names(names)
+          end
+        end
+      end
+
+      def include_prereleases(names)
+        names.each do |name|
+          get_package(name).consider_prereleases!
+        end
+      end
+
+      private
+
+      def indirect_pins(names)
+        names.select {|name| @base_requirements[name].exact? && @requirements.none? {|dep| dep.name == name } }
+      end
+
+      def pins(names)
+        names.select {|name| @base_requirements[name].exact? }
+      end
+
+      def loosen_names(names)
+        names.each do |name|
+          version = @base_requirements[name].requirements.first[1]
+
+          @base_requirements[name] = Gem::Requirement.new(">= #{version}")
+
+          @base.delete_by_name(name)
+        end
+      end
+
+      def unrestrict_names(names)
+        names.each do |name|
+          @base_requirements.delete(name)
+        end
+      end
+
+      def build_base_requirements
+        base_requirements = {}
+        @base.each do |ls|
+          req = Gem::Requirement.new(ls.version)
+          base_requirements[ls.name] = req
+        end
+        base_requirements
+      end
+    end
+  end
+end
diff --git a/lib/bundler/resolver/candidate.rb b/lib/bundler/resolver/candidate.rb
new file mode 100644
index 0000000000..e695ef08ee
--- /dev/null
+++ b/lib/bundler/resolver/candidate.rb
@@ -0,0 +1,94 @@
+# frozen_string_literal: true
+
+require_relative "spec_group"
+
+module Bundler
+  class Resolver
+    #
+    # This class is a PubGrub compatible "Version" class that takes Bundler
+    # resolution complexities into account.
+    #
+    # Each Resolver::Candidate has a underlying `Gem::Version` plus a set of
+    # platforms. For example, 1.1.0-x86_64-linux is a different resolution candidate
+    # from 1.1.0 (generic). This is because different platform variants of the
+    # same gem version can bring different dependencies, so they need to be
+    # considered separately.
+    #
+    # Some candidates may also keep some information explicitly about the
+    # package the refer to. These candidates are referred to as "canonical" and
+    # are used when materializing resolution results back into RubyGems
+    # specifications that can be installed, written to lock files, and so on.
+    #
+    class Candidate
+      include Comparable
+
+      attr_reader :version
+
+      def initialize(version, specs: [])
+        @spec_group = Resolver::SpecGroup.new(specs)
+        @version = Gem::Version.new(version)
+        @ruby_only = specs.map(&:platform).uniq == [Gem::Platform::RUBY]
+      end
+
+      def dependencies
+        @spec_group.dependencies
+      end
+
+      def to_specs(package)
+        return [] if package.meta?
+
+        @spec_group.to_specs(package.force_ruby_platform?)
+      end
+
+      def generic!
+        @ruby_only = true
+
+        self
+      end
+
+      def platform_specific!
+        @ruby_only = false
+
+        self
+      end
+
+      def prerelease?
+        @version.prerelease?
+      end
+
+      def segments
+        @version.segments
+      end
+
+      def sort_obj
+        [@version, @ruby_only ? -1 : 1]
+      end
+
+      def <=>(other)
+        return unless other.is_a?(self.class)
+
+        sort_obj <=> other.sort_obj
+      end
+
+      def ==(other)
+        return unless other.is_a?(self.class)
+
+        sort_obj == other.sort_obj
+      end
+
+      def eql?(other)
+        return unless other.is_a?(self.class)
+
+        sort_obj.eql?(other.sort_obj)
+      end
+
+      def hash
+        sort_obj.hash
+      end
+
+      def to_s
+        @version.to_s
+      end
+    end
+  end
+end
diff --git a/lib/bundler/resolver/incompatibility.rb b/lib/bundler/resolver/incompatibility.rb
new file mode 100644
index 0000000000..c61151fbeb
--- /dev/null
+++ b/lib/bundler/resolver/incompatibility.rb
@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+module Bundler
+  class Resolver
+    class Incompatibility < PubGrub::Incompatibility
+      attr_reader :extended_explanation
+
+      def initialize(terms, cause:, custom_explanation: nil, extended_explanation: nil)
+        @extended_explanation = extended_explanation
+
+        super(terms, :cause => cause, :custom_explanation => custom_explanation)
+      end
+    end
+  end
+end
diff --git a/lib/bundler/resolver/package.rb b/lib/bundler/resolver/package.rb
new file mode 100644
index 0000000000..7499a75006
--- /dev/null
+++ b/lib/bundler/resolver/package.rb
@@ -0,0 +1,72 @@
+# frozen_string_literal: true
+
+module Bundler
+  class Resolver
+    #
+    # Represents a gem being resolved, in a format PubGrub likes.
+    #
+    # The class holds the following information:
+    #
+    # * Platforms this gem will be resolved on.
+    # * The locked version of this gem resolution should favor (if any).
+    # * Whether the gem should be unlocked to its latest version.
+    # * The dependency explicit set in the Gemfile for this gem (if any).
+    #
+    class Package
+      attr_reader :name, :platforms, :dependency, :locked_version
+
+      def initialize(name, platforms, locked_specs:, unlock:, prerelease: false, dependency: nil)
+        @name = name
+        @platforms = platforms
+        @locked_version = locked_specs[name].first&.version
+        @unlock = unlock
+        @dependency = dependency || Dependency.new(name, @locked_version)
+        @prerelease = @dependency.prerelease? || @locked_version&.prerelease? || prerelease ? :consider_first : :ignore
+      end
+
+      def to_s
+        @name.delete("\0")
+      end
+
+      def root?
+        false
+      end
+
+      def meta?
+        @name.end_with?("\0")
+      end
+
+      def ==(other)
+        self.class == other.class && @name == other.name
+      end
+
+      def hash
+        @name.hash
+      end
+
+      def unlock?
+        @unlock.empty? || @unlock.include?(name)
+      end
+
+      def ignores_prereleases?
+        @prerelease == :ignore
+      end
+
+      def prerelease_specified?
+        @prerelease == :consider_first
+      end
+
+      def consider_prereleases!
+        @prerelease = :consider_last
+      end
+
+      def force_ruby_platform?
+        @dependency.force_ruby_platform
+      end
+
+      def current_platform?
+        @dependency.current_platform?
+      end
+    end
+  end
+end
diff --git a/lib/bundler/resolver/root.rb b/lib/bundler/resolver/root.rb
new file mode 100644
index 0000000000..e5eb634fb8
--- /dev/null
+++ b/lib/bundler/resolver/root.rb
@@ -0,0 +1,25 @@
+# frozen_string_literal: true
+
+require_relative "package"
+
+module Bundler
+  class Resolver
+    #
+    # Represents the Gemfile from the resolver's perspective. It's the root
+    # package and Gemfile entries depend on it.
+    #
+    class Root < Package
+      def initialize(name)
+        @name = name
+      end
+
+      def meta?
+        true
+      end
+
+      def root?
+        true
+      end
+    end
+  end
+end
diff --git a/lib/bundler/resolver/spec_group.rb b/lib/bundler/resolver/spec_group.rb
index 232520de77..b44c19a73f 100644
--- a/lib/bundler/resolver/spec_group.rb
+++ b/lib/bundler/resolver/spec_group.rb
@@ -3,107 +3,79 @@
 module Bundler
   class Resolver
     class SpecGroup
-      attr_accessor :name, :version, :source
-      attr_accessor :activated_platforms
-
-      def self.create_for(specs, all_platforms, specific_platform)
-        specific_platform_specs = specs[specific_platform]
-        return unless specific_platform_specs.any?
-
-        platforms = all_platforms.select {|p| specs[p].any? }
-
-        new(specific_platform_specs.first, specs, platforms)
+      def initialize(specs)
+        @specs = specs
       end
 
-      def initialize(exemplary_spec, specs, relevant_platforms)
-        @exemplary_spec = exemplary_spec
-        @name = exemplary_spec.name
-        @version = exemplary_spec.version
-        @source = exemplary_spec.source
-
-        @activated_platforms = relevant_platforms
-        @dependencies = Hash.new do |dependencies, platforms|
-          dependencies[platforms] = dependencies_for(platforms)
-        end
-        @specs = specs
+      def empty?
+        @specs.empty?
       end
 
-      def to_specs
-        activated_platforms.map do |p|
-          specs = @specs[p]
-          next unless specs.any?
-
-          specs.map do |s|
-            lazy_spec = LazySpecification.new(name, version, s.platform, source)
-            lazy_spec.dependencies.replace s.dependencies
-            lazy_spec
-          end
-        end.flatten.compact.uniq
+      def name
+        @name ||= exemplary_spec.name
       end
 
-      def to_s
-        activated_platforms_string = sorted_activated_platforms.join(", ")
-        "#{name} (#{version}) (#{activated_platforms_string})"
+      def version
+        @version ||= exemplary_spec.version
       end
 
-      def dependencies_for_activated_platforms
-        @dependencies[activated_platforms]
+      def source
+        @source ||= exemplary_spec.source
       end
 
-      def ==(other)
-        return unless other.is_a?(SpecGroup)
-        name == other.name &&
-          version == other.version &&
-          sorted_activated_platforms == other.sorted_activated_platforms &&
-          source == other.source
+      def to_specs(force_ruby_platform)
+        @specs.map do |s|
+          lazy_spec = LazySpecification.new(name, version, s.platform, source)
+          lazy_spec.force_ruby_platform = force_ruby_platform
+          lazy_spec.dependencies.replace s.dependencies
+          lazy_spec
+        end
       end
 
-      def eql?(other)
-        return unless other.is_a?(SpecGroup)
-        name.eql?(other.name) &&
-          version.eql?(other.version) &&
-          sorted_activated_platforms.eql?(other.sorted_activated_platforms) &&
-          source.eql?(other.source)
+      def to_s
+        sorted_spec_names.join(", ")
       end
 
-      def hash
-        name.hash ^ version.hash ^ sorted_activated_platforms.hash ^ source.hash
+      def dependencies
+        @dependencies ||= @specs.map do |spec|
+          __dependencies(spec) + metadata_dependencies(spec)
+        end.flatten.uniq
       end
 
       protected
 
-      def sorted_activated_platforms
-        activated_platforms.sort_by(&:to_s)
+      def sorted_spec_names
+        @sorted_spec_names ||= @specs.map(&:full_name).sort
       end
 
       private
 
-      def dependencies_for(platforms)
-        platforms.map do |platform|
-          __dependencies(platform) + metadata_dependencies(platform)
-        end.flatten
+      def exemplary_spec
+        @specs.first
       end
 
-      def __dependencies(platform)
+      def __dependencies(spec)
         dependencies = []
-        @specs[platform].first.dependencies.each do |dep|
+        spec.dependencies.each do |dep|
           next if dep.type == :development
-          dependencies << DepProxy.get_proxy(dep, platform)
+          dependencies << Dependency.new(dep.name, dep.requirement)
         end
         dependencies
       end
 
-      def metadata_dependencies(platform)
-        spec = @specs[platform].first
+      def metadata_dependencies(spec)
         return [] if spec.is_a?(LazySpecification)
-        dependencies = []
-        if !spec.required_ruby_version.nil? && !spec.required_ruby_version.none?
-          dependencies << DepProxy.get_proxy(Gem::Dependency.new("Ruby\0", spec.required_ruby_version), platform)
-        end
-        if !spec.required_rubygems_version.nil? && !spec.required_rubygems_version.none?
-          dependencies << DepProxy.get_proxy(Gem::Dependency.new("RubyGems\0", spec.required_rubygems_version), platform)
-        end
-        dependencies
+
+        [
+          metadata_dependency("Ruby", spec.required_ruby_version),
+          metadata_dependency("RubyGems", spec.required_rubygems_version),
+        ].compact
+      end
+
+      def metadata_dependency(name, requirement)
+        return if requirement.nil? || requirement.none?
+
+        Dependency.new("#{name}\0", requirement)
       end
     end
   end
diff --git a/lib/bundler/ruby_dsl.rb b/lib/bundler/ruby_dsl.rb
index f6ba220cd5..d054969e8d 100644
--- a/lib/bundler/ruby_dsl.rb
+++ b/lib/bundler/ruby_dsl.rb
@@ -5,11 +5,17 @@ module Bundler
     def ruby(*ruby_version)
       options = ruby_version.last.is_a?(Hash) ? ruby_version.pop : {}
       ruby_version.flatten!
+
       raise GemfileError, "Please define :engine_version" if options[:engine] && options[:engine_version].nil?
       raise GemfileError, "Please define :engine" if options[:engine_version] && options[:engine].nil?
 
+      if options[:file]
+        raise GemfileError, "Cannot specify version when using the file option" if ruby_version.any?
+        ruby_version << Bundler.read_file(options[:file]).strip
+      end
+
       if options[:engine] == "ruby" && options[:engine_version] &&
-          ruby_version != Array(options[:engine_version])
+         ruby_version != Array(options[:engine_version])
         raise GemfileEvalError, "ruby_version must match the :engine_version for MRI"
       end
       @ruby_version = RubyVersion.new(ruby_version, options[:patchlevel], options[:engine], options[:engine_version])
diff --git a/lib/bundler/ruby_version.rb b/lib/bundler/ruby_version.rb
index d3b7963920..b5396abb6e 100644
--- a/lib/bundler/ruby_version.rb
+++ b/lib/bundler/ruby_version.rb
@@ -28,16 +28,16 @@ module Bundler
       end
 
       @gem_version        = Gem::Requirement.create(@versions.first).requirements.first.last
-      @input_engine       = engine && engine.to_s
-      @engine             = engine && engine.to_s || "ruby"
+      @input_engine       = engine&.to_s
+      @engine             = engine&.to_s || "ruby"
       @engine_versions    = (engine_version && Array(engine_version)) || @versions
       @engine_gem_version = Gem::Requirement.create(@engine_versions.first).requirements.first.last
-      @patchlevel         = patchlevel
+      @patchlevel         = patchlevel || (@gem_version.prerelease? ? "-1" : nil)
     end
 
     def to_s(versions = self.versions)
       output = String.new("ruby #{versions_string(versions)}")
-      output << "p#{patchlevel}" if patchlevel
+      output << "p#{patchlevel}" if patchlevel && patchlevel != "-1"
       output << " (#{engine} #{versions_string(engine_versions)})" unless engine == "ruby"
 
       output
@@ -46,7 +46,7 @@ module Bundler
     # @private
     PATTERN = /
       ruby\s
-      ([\d.]+) # ruby version
+      (\d+\.\d+\.\d+(?:\.\S+)?) # ruby version
       (?:p(-?\d+))? # optional patchlevel
       (?:\s\((\S+)\s(.+)\))? # optional engine info
     /xo.freeze
@@ -103,24 +103,11 @@ module Bundler
 
     def self.system
       ruby_engine = RUBY_ENGINE.dup
-      ruby_version = RUBY_VERSION.dup
-      ruby_engine_version = RUBY_ENGINE_VERSION.dup
+      ruby_version = Gem.ruby_version.to_s
+      ruby_engine_version = RUBY_ENGINE == "ruby" ? ruby_version : RUBY_ENGINE_VERSION.dup
       patchlevel = RUBY_PATCHLEVEL.to_s
 
-      @ruby_version ||= RubyVersion.new(ruby_version, patchlevel, ruby_engine, ruby_engine_version)
-    end
-
-    def to_gem_version_with_patchlevel
-      @gem_version_with_patch ||= begin
-        Gem::Version.create("#{@gem_version}.#{@patchlevel}")
-      rescue ArgumentError
-        @gem_version
-      end
-    end
-
-    def exact?
-      return @exact if defined?(@exact)
-      @exact = versions.all? {|v| Gem::Requirement.create(v).exact? }
+      @system ||= RubyVersion.new(ruby_version, patchlevel, ruby_engine, ruby_engine_version)
     end
 
     private
diff --git a/lib/bundler/rubygems_ext.rb b/lib/bundler/rubygems_ext.rb
index cc06b9ee93..8981612706 100644
--- a/lib/bundler/rubygems_ext.rb
+++ b/lib/bundler/rubygems_ext.rb
@@ -4,10 +4,33 @@ require "pathname"
 
 require "rubygems/specification"
 
+# We can't let `Gem::Source` be autoloaded in the `Gem::Specification#source`
+# redefinition below, so we need to load it upfront. The reason is that if
+# Bundler monkeypatches are loaded before RubyGems activates an executable (for
+# example, through `ruby -rbundler -S irb`), gem activation might end up calling
+# the redefined `Gem::Specification#source` and triggering the `Gem::Source`
+# autoload. That would result in requiring "rubygems/source" inside another
+# require, which would trigger a monitor error and cause the `autoload` to
+# eventually fail. A better solution is probably to completely avoid autoloading
+# `Gem::Source` from the redefined `Gem::Specification#source`.
+require "rubygems/source"
+
+require_relative "match_metadata"
+require_relative "force_platform"
 require_relative "match_platform"
 
+# Cherry-pick fixes to `Gem.ruby_version` to be useful for modern Bundler
+# versions and ignore patchlevels
+# (https://github.com/rubygems/rubygems/pull/5472,
+# https://github.com/rubygems/rubygems/pull/5486). May be removed once RubyGems
+# 3.3.12 support is dropped.
+unless Gem.ruby_version.to_s == RUBY_VERSION || RUBY_PATCHLEVEL == -1
+  Gem.instance_variable_set(:@ruby_version, Gem::Version.new(RUBY_VERSION))
+end
+
 module Gem
   class Specification
+    include ::Bundler::MatchMetadata
     include ::Bundler::MatchPlatform
 
     attr_accessor :remote, :location, :relative_loaded_from
@@ -22,12 +45,8 @@ module Gem
     alias_method :rg_loaded_from,   :loaded_from
 
     def full_gem_path
-      # this cannot check source.is_a?(Bundler::Plugin::API::Source)
-      # because that _could_ trip the autoload, and if there are unresolved
-      # gems at that time, this method could be called inside another require,
-      # thus raising with that constant being undefined. Better to check a method
-      if source.respond_to?(:path) || (source.respond_to?(:bundler_plugin_api_source?) && source.bundler_plugin_api_source?)
-        Pathname.new(loaded_from).dirname.expand_path(source.root).to_s.tap{|x| x.untaint if RUBY_VERSION < "2.7" }
+      if source.respond_to?(:root)
+        Pathname.new(loaded_from).dirname.expand_path(source.root).to_s.tap {|x| x.untaint if RUBY_VERSION < "2.7" }
       else
         rg_full_gem_path
       end
@@ -47,7 +66,9 @@ module Gem
 
     alias_method :rg_extension_dir, :extension_dir
     def extension_dir
-      @bundler_extension_dir ||= if source.respond_to?(:extension_dir_name)
+      # following instance variable is already used in original method
+      # and that is the reason to prefix it with bundler_ and add rubocop exception
+      @bundler_extension_dir ||= if source.respond_to?(:extension_dir_name) # rubocop:disable Naming/MemoizedInstanceVariableName
         unique_extension_dir = [source.extension_dir_name, File.basename(full_gem_path)].uniq.join("-")
         File.expand_path(File.join(extensions_dir, unique_extension_dir))
       else
@@ -60,6 +81,23 @@ module Gem
       full_gem_path
     end
 
+    unless const_defined?(:LATEST_RUBY_WITHOUT_PATCH_VERSIONS)
+      LATEST_RUBY_WITHOUT_PATCH_VERSIONS = Gem::Version.new("2.1")
+
+      alias_method :rg_required_ruby_version=, :required_ruby_version=
+      def required_ruby_version=(req)
+        self.rg_required_ruby_version = req
+
+        @required_ruby_version.requirements.map! do |op, v|
+          if v >= LATEST_RUBY_WITHOUT_PATCH_VERSIONS && v.release.segments.size == 4
+            [op == "~>" ? "=" : op, Gem::Version.new(v.segments.tap {|s| s.delete_at(3) }.join("."))]
+          else
+            [op, v]
+          end
+        end
+      end
+    end
+
     def groups
       @groups ||= []
     end
@@ -118,10 +156,18 @@ module Gem
   end
 
   class Dependency
+    include ::Bundler::ForcePlatform
+
     attr_accessor :source, :groups
 
     alias_method :eql?, :==
 
+    def force_ruby_platform
+      return @force_ruby_platform if defined?(@force_ruby_platform) && !@force_ruby_platform.nil?
+
+      @force_ruby_platform = default_force_ruby_platform
+    end
+
     def encode_with(coder)
       to_yaml_properties.each do |ivar|
         coder[ivar.to_s.sub(/^@/, "")] = instance_variable_get(ivar)
@@ -159,9 +205,9 @@ module Gem
         protected
 
         def _requirements_sorted?
-          return @_are_requirements_sorted if defined?(@_are_requirements_sorted)
+          return @_requirements_sorted if defined?(@_requirements_sorted)
           strings = as_list
-          @_are_requirements_sorted = strings == strings.sort
+          @_requirements_sorted = strings == strings.sort
         end
 
         def _with_sorted_requirements
@@ -192,11 +238,56 @@ module Gem
   require "rubygems/platform"
 
   class Platform
-    JAVA  = Gem::Platform.new("java") unless defined?(JAVA)
-    MSWIN = Gem::Platform.new("mswin32") unless defined?(MSWIN)
-    MSWIN64 = Gem::Platform.new("mswin64") unless defined?(MSWIN64)
-    MINGW = Gem::Platform.new("x86-mingw32") unless defined?(MINGW)
-    X64_MINGW = Gem::Platform.new("x64-mingw32") unless defined?(X64_MINGW)
+    JAVA  = Gem::Platform.new("java")
+    MSWIN = Gem::Platform.new("mswin32")
+    MSWIN64 = Gem::Platform.new("mswin64")
+    MINGW = Gem::Platform.new("x86-mingw32")
+    X64_MINGW = [Gem::Platform.new("x64-mingw32"),
+                 Gem::Platform.new("x64-mingw-ucrt")].freeze
+    WINDOWS = [MSWIN, MSWIN64, MINGW, X64_MINGW].flatten.freeze
+    X64_LINUX = Gem::Platform.new("x86_64-linux")
+    X64_LINUX_MUSL = Gem::Platform.new("x86_64-linux-musl")
+
+    if X64_LINUX === X64_LINUX_MUSL
+      remove_method :===
+
+      def ===(other)
+        return nil unless Gem::Platform === other
+
+        # universal-mingw32 matches x64-mingw-ucrt
+        return true if (@cpu == "universal" || other.cpu == "universal") &&
+                       @os.start_with?("mingw") && other.os.start_with?("mingw")
+
+        # cpu
+        ([nil,"universal"].include?(@cpu) || [nil, "universal"].include?(other.cpu) || @cpu == other.cpu ||
+        (@cpu == "arm" && other.cpu.start_with?("arm"))) &&
+
+          # os
+          @os == other.os &&
+
+          # version
+          (
+            (@os != "linux" && (@version.nil? || other.version.nil?)) ||
+            (@os == "linux" && (normalized_linux_version_ext == other.normalized_linux_version_ext || ["musl#{@version}", "musleabi#{@version}", "musleabihf#{@version}"].include?(other.version))) ||
+            @version == other.version
+          )
+      end
+
+      # This is a copy of RubyGems 3.3.23 or higher `normalized_linux_method`.
+      # Once only 3.3.23 is supported, we can use the method in RubyGems.
+      def normalized_linux_version_ext
+        return nil unless @version
+
+        without_gnu_nor_abi_modifiers = @version.sub(/\Agnu/, "").sub(/eabi(hf)?\Z/, "")
+        return nil if without_gnu_nor_abi_modifiers.empty?
+
+        without_gnu_nor_abi_modifiers
+      end
+    end
+
+    if RUBY_ENGINE == "truffleruby" && !defined?(REUSE_AS_BINARY_ON_TRUFFLERUBY)
+      REUSE_AS_BINARY_ON_TRUFFLERUBY = %w[libv8 libv8-node sorbet-static].freeze
+    end
   end
 
   Platform.singleton_class.module_eval do
@@ -208,14 +299,43 @@ module Gem
       def match_gem?(platform, gem_name)
         match_platforms?(platform, Gem.platforms)
       end
+    end
+
+    match_platforms_defined = Gem::Platform.respond_to?(:match_platforms?, true)
+
+    if !match_platforms_defined || Gem::Platform.send(:match_platforms?, Gem::Platform::X64_LINUX_MUSL, [Gem::Platform::X64_LINUX])
 
       private
 
+      remove_method :match_platforms? if match_platforms_defined
+
       def match_platforms?(platform, platforms)
         platforms.any? do |local_platform|
           platform.nil? ||
             local_platform == platform ||
-            (local_platform != Gem::Platform::RUBY && local_platform =~ platform)
+            (local_platform != Gem::Platform::RUBY && platform =~ local_platform)
+        end
+      end
+    end
+  end
+
+  # On universal Rubies, resolve the "universal" arch to the real CPU arch, without changing the extension directory.
+  class Specification
+    if /^universal\.(?<arch>.*?)-/ =~ (CROSS_COMPILING || RUBY_PLATFORM)
+      local_platform = Platform.local
+      if local_platform.cpu == "universal"
+        ORIGINAL_LOCAL_PLATFORM = local_platform.to_s.freeze
+
+        local_platform.cpu = if arch == "arm64e" # arm64e is only permitted for Apple system binaries
+          "arm64"
+        else
+          arch
+        end
+
+        def extensions_dir
+          Gem.default_ext_dir_for(base_dir) ||
+            File.join(base_dir, "extensions", ORIGINAL_LOCAL_PLATFORM,
+                      Gem.extension_api_version)
         end
       end
     end
@@ -229,11 +349,7 @@ module Gem
     end
 
     def glob_files_in_dir(glob, base_path)
-      if RUBY_VERSION >= "2.5"
-        Dir.glob(glob, :base => base_path).map! {|f| File.expand_path(f, base_path) }
-      else
-        Dir.glob(File.join(base_path.to_s.gsub(/[\[\]]/, '\\\\\\&'), glob)).map! {|f| File.expand_path(f) }
-      end
+      Dir.glob(glob, :base => base_path).map! {|f| File.expand_path(f, base_path) }
     end
   end
 end
diff --git a/lib/bundler/rubygems_gem_installer.rb b/lib/bundler/rubygems_gem_installer.rb
index 452583617b..38035a00ac 100644
--- a/lib/bundler/rubygems_gem_installer.rb
+++ b/lib/bundler/rubygems_gem_installer.rb
@@ -25,7 +25,7 @@ module Bundler
 
       extract_files
 
-      build_extensions
+      build_extensions if spec.extensions.any?
       write_build_info_file
       run_post_build_hooks
 
@@ -66,41 +66,53 @@ module Bundler
 
     def build_extensions
       extension_cache_path = options[:bundler_extension_cache_path]
-      unless extension_cache_path && extension_dir = spec.extension_dir
-        require "shellwords" unless Bundler.rubygems.provides?(">= 3.2.25")
+      extension_dir = spec.extension_dir
+      unless extension_cache_path && extension_dir
+        prepare_extension_build(extension_dir)
         return super
       end
 
-      extension_dir = Pathname.new(extension_dir)
       build_complete = SharedHelpers.filesystem_access(extension_cache_path.join("gem.build_complete"), :read, &:file?)
       if build_complete && !options[:force]
-        SharedHelpers.filesystem_access(extension_dir.parent, &:mkpath)
+        SharedHelpers.filesystem_access(File.dirname(extension_dir)) do |p|
+          FileUtils.mkpath p
+        end
         SharedHelpers.filesystem_access(extension_cache_path) do
-          FileUtils.cp_r extension_cache_path, spec.extension_dir
+          FileUtils.cp_r extension_cache_path, extension_dir
         end
       else
-        require "shellwords" # compensate missing require in rubygems before version 3.2.25
+        prepare_extension_build(extension_dir)
         super
-        if extension_dir.directory? # not made for gems without extensions
-          SharedHelpers.filesystem_access(extension_cache_path.parent, &:mkpath)
-          SharedHelpers.filesystem_access(extension_cache_path) do
-            FileUtils.cp_r extension_dir, extension_cache_path
-          end
+        SharedHelpers.filesystem_access(extension_cache_path.parent, &:mkpath)
+        SharedHelpers.filesystem_access(extension_cache_path) do
+          FileUtils.cp_r extension_dir, extension_cache_path
         end
       end
     end
 
+    def spec
+      if Bundler.rubygems.provides?("< 3.3.12") # RubyGems implementation rescues and re-raises errors before 3.3.12 and we don't want that
+        @package.spec
+      else
+        super
+      end
+    end
+
     private
 
+    def prepare_extension_build(extension_dir)
+      SharedHelpers.filesystem_access(extension_dir, :create) do
+        FileUtils.mkdir_p extension_dir
+      end
+      require "shellwords" unless Bundler.rubygems.provides?(">= 3.2.25")
+    end
+
     def strict_rm_rf(dir)
-      # FileUtils.rm_rf should probably rise in case of permission issues like
-      # `rm -rf` does. However, it fails to delete the folder silently due to
-      # https://github.com/ruby/fileutils/issues/57. It should probably be fixed
-      # inside `fileutils` but for now I`m checking whether the folder was
-      # removed after it completes, and raising otherwise.
-      FileUtils.rm_rf dir
-
-      raise PermissionError.new(dir, :delete) if File.directory?(dir)
+      Bundler.rm_rf dir
+    rescue StandardError => e
+      raise unless File.exist?(dir)
+
+      raise DirectoryRemovalError.new(e, "Could not delete previous installation of `#{dir}`")
     end
 
     def validate_bundler_checksum(checksum)
diff --git a/lib/bundler/rubygems_integration.rb b/lib/bundler/rubygems_integration.rb
index 1c2b374d8b..d8b7886af7 100644
--- a/lib/bundler/rubygems_integration.rb
+++ b/lib/bundler/rubygems_integration.rb
@@ -203,20 +203,9 @@ module Bundler
       EXT_LOCK
     end
 
-    def spec_from_gem(path, policy = nil)
-      require "rubygems/security"
-      require "psych"
-      gem_from_path(path, security_policies[policy]).spec
-    rescue Exception, Gem::Exception, Gem::Security::Exception => e # rubocop:disable Lint/RescueException
-      if e.is_a?(Gem::Security::Exception) ||
-          e.message =~ /unknown trust policy|unsigned gem/i ||
-          e.message =~ /couldn't verify (meta)?data signature/i
-        raise SecurityError,
-          "The gem #{File.basename(path, ".gem")} can't be installed because " \
-          "the security policy didn't allow it, with the message: #{e.message}"
-      else
-        raise e
-      end
+    def spec_from_gem(path)
+      require "rubygems/package"
+      Gem::Package.new(path).spec
     end
 
     def build_gem(gem_dir, spec)
@@ -238,10 +227,14 @@ module Bundler
 
     def reverse_rubygems_kernel_mixin
       # Disable rubygems' gem activation system
-      kernel = (class << ::Kernel; self; end)
-      [kernel, ::Kernel].each do |k|
-        if k.private_method_defined?(:gem_original_require)
-          redefine_method(k, :require, k.instance_method(:gem_original_require))
+      if Gem.respond_to?(:discover_gems_on_require=)
+        Gem.discover_gems_on_require = false
+      else
+        kernel = (class << ::Kernel; self; end)
+        [kernel, ::Kernel].each do |k|
+          if k.private_method_defined?(:gem_original_require)
+            redefine_method(k, :require, k.instance_method(:gem_original_require))
+          end
         end
       end
     end
@@ -254,7 +247,7 @@ module Bundler
       kernel = (class << ::Kernel; self; end)
       [kernel, ::Kernel].each do |kernel_class|
         redefine_method(kernel_class, :gem) do |dep, *reqs|
-          if executables && executables.include?(File.basename(caller.first.split(":").first))
+          if executables&.include?(File.basename(caller.first.split(":").first))
             break
           end
 
@@ -283,11 +276,7 @@ module Bundler
 
           e = Gem::LoadError.new(message)
           e.name = dep.name
-          if e.respond_to?(:requirement=)
-            e.requirement = dep.requirement
-          elsif e.respond_to?(:version_requirement=)
-            e.version_requirement = dep.requirement
-          end
+          e.requirement = dep.requirement
           raise e
         end
 
@@ -464,7 +453,7 @@ module Bundler
       fetcher = gem_remote_fetcher
       fetcher.headers = { "X-Gemfile-Source" => remote.original_uri.to_s } if remote.original_uri
       string = fetcher.fetch_path(path)
-      Bundler.load_marshal(string)
+      Bundler.safe_load_marshal(string)
     rescue Gem::RemoteFetcher::FetchError
       # it's okay for prerelease to fail
       raise unless name == "prerelease_specs"
@@ -514,22 +503,11 @@ module Bundler
       Gem::RemoteFetcher.new(proxy)
     end
 
-    def gem_from_path(path, policy = nil)
-      require "rubygems/package"
-      p = Gem::Package.new(path)
-      p.security_policy = policy if policy
-      p
-    end
-
     def build(spec, skip_validation = false)
       require "rubygems/package"
       Gem::Package.build(spec, skip_validation)
     end
 
-    def repository_subdirectories
-      Gem::REPOSITORY_SUBDIRECTORIES
-    end
-
     def path_separator
       Gem.path_separator
     end
diff --git a/lib/bundler/runtime.rb b/lib/bundler/runtime.rb
index c7276b0e25..95cf78dd41 100644
--- a/lib/bundler/runtime.rb
+++ b/lib/bundler/runtime.rb
@@ -94,7 +94,7 @@ module Bundler
     definition_method :requires
 
     def lock(opts = {})
-      return if @definition.nothing_changed? && !@definition.unlocking?
+      return if @definition.no_resolve_needed?
       @definition.lock(Bundler.default_lockfile, opts[:preserve_unknown_sections])
     end
 
@@ -125,7 +125,6 @@ module Bundler
       specs_to_cache.each do |spec|
         next if spec.name == "bundler"
         next if spec.source.is_a?(Source::Gemspec)
-        spec.source.send(:fetch_gem, spec) if Bundler.settings[:cache_all_platforms] && spec.source.respond_to?(:fetch_gem, true)
         spec.source.cache(spec, custom_path) if spec.source.respond_to?(:cache)
       end
 
@@ -301,11 +300,7 @@ module Bundler
       e = Gem::LoadError.new "You have already activated #{activated_spec.name} #{activated_spec.version}, " \
                              "but your Gemfile requires #{spec.name} #{spec.version}. #{suggestion}"
       e.name = spec.name
-      if e.respond_to?(:requirement=)
-        e.requirement = Gem::Requirement.new(spec.version.to_s)
-      else
-        e.version_requirement = Gem::Requirement.new(spec.version.to_s)
-      end
+      e.requirement = Gem::Requirement.new(spec.version.to_s)
       raise e
     end
   end
diff --git a/lib/bundler/safe_marshal.rb b/lib/bundler/safe_marshal.rb
new file mode 100644
index 0000000000..50aa0f60a6
--- /dev/null
+++ b/lib/bundler/safe_marshal.rb
@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+module Bundler
+  module SafeMarshal
+    ALLOWED_CLASSES = [
+      Array,
+      FalseClass,
+      Gem::Specification,
+      Gem::Version,
+      Hash,
+      String,
+      Symbol,
+      Time,
+      TrueClass,
+    ].freeze
+
+    ERROR = "Unexpected class %s present in marshaled data. Only %s are allowed."
+
+    PROC = proc do |object|
+      object.tap do
+        unless ALLOWED_CLASSES.include?(object.class)
+          raise TypeError, format(ERROR, object.class, ALLOWED_CLASSES.join(", "))
+        end
+      end
+    end
+
+    def self.proc
+      PROC
+    end
+  end
+end
diff --git a/lib/bundler/settings.rb b/lib/bundler/settings.rb
index 8f263cd012..0af2236a45 100644
--- a/lib/bundler/settings.rb
+++ b/lib/bundler/settings.rb
@@ -43,9 +43,7 @@ module Bundler
       setup_makes_kernel_gem_public
       silence_deprecations
       silence_root_warning
-      suppress_install_using_messages
       update_requires_all_flag
-      use_gem_version_promoter_for_major_updates
     ].freeze
 
     NUMBER_KEYS = %w[
@@ -57,6 +55,7 @@ module Bundler
     ].freeze
 
     ARRAY_KEYS = %w[
+      only
       with
       without
     ].freeze
@@ -219,7 +218,6 @@ module Bundler
     def path
       configs.each do |_level, settings|
         path = value_for("path", settings)
-        path = "vendor/bundle" if value_for("deployment", settings) && path.nil?
         path_system = value_for("path.system", settings)
         disabled_shared_gems = value_for("disable_shared_gems", settings)
         next if path.nil? && path_system.nil? && disabled_shared_gems.nil?
@@ -227,7 +225,9 @@ module Bundler
         return Path.new(path, system_path)
       end
 
-      Path.new(nil, false)
+      path = "vendor/bundle" if self[:deployment]
+
+      Path.new(path, false)
     end
 
     Path = Struct.new(:explicit_path, :system_path) do
@@ -277,12 +277,6 @@ module Bundler
       end
     end
 
-    def allow_sudo?
-      key = key_for(:path)
-      path_configured = @temporary.key?(key) || @local_config.key?(key)
-      !path_configured
-    end
-
     def ignore_config?
       ENV["BUNDLE_IGNORE_CONFIG"]
     end
@@ -487,7 +481,7 @@ module Bundler
       /ix.freeze
 
     def self.key_for(key)
-      key = normalize_uri(key).to_s if key.is_a?(String) && /https?:/ =~ key
+      key = normalize_uri(key).to_s if key.is_a?(String) && key.start_with?("http", "mirror.http")
       key = key.to_s.gsub(".", "__").gsub("-", "___").upcase
       "BUNDLE_#{key}"
     end
@@ -501,7 +495,7 @@ module Bundler
         uri = $2
         suffix = $3
       end
-      uri = "#{uri}/" unless uri.end_with?("/")
+      uri = URINormalizer.normalize_suffix(uri)
       require_relative "vendored_uri"
       uri = Bundler::URI(uri)
       unless uri.absolute?
diff --git a/lib/bundler/setup.rb b/lib/bundler/setup.rb
index 32e9b2d7c0..801fd5312a 100644
--- a/lib/bundler/setup.rb
+++ b/lib/bundler/setup.rb
@@ -12,7 +12,10 @@ if Bundler::SharedHelpers.in_bundle?
       Bundler.ui.error e.message
       Bundler.ui.warn e.backtrace.join("\n") if ENV["DEBUG"]
       if e.is_a?(Bundler::GemNotFound)
-        Bundler.ui.warn "Run `bundle install` to install missing gems."
+        suggested_cmd = "bundle install"
+        original_gemfile = Bundler.original_env["BUNDLE_GEMFILE"]
+        suggested_cmd += " --gemfile #{original_gemfile}" if original_gemfile
+        Bundler.ui.warn "Run `#{suggested_cmd}` to install missing gems."
       end
       exit e.status_code
     end
diff --git a/lib/bundler/shared_helpers.rb b/lib/bundler/shared_helpers.rb
index 8b476c9135..d1d4e1d07a 100644
--- a/lib/bundler/shared_helpers.rb
+++ b/lib/bundler/shared_helpers.rb
@@ -13,13 +13,13 @@ module Bundler
     def root
       gemfile = find_gemfile
       raise GemfileNotFound, "Could not locate Gemfile" unless gemfile
-      Pathname.new(gemfile).tap{|x| x.untaint if RUBY_VERSION < "2.7" }.expand_path.parent
+      Pathname.new(gemfile).tap {|x| x.untaint if RUBY_VERSION < "2.7" }.expand_path.parent
     end
 
     def default_gemfile
       gemfile = find_gemfile
       raise GemfileNotFound, "Could not locate Gemfile" unless gemfile
-      Pathname.new(gemfile).tap{|x| x.untaint if RUBY_VERSION < "2.7" }.expand_path
+      Pathname.new(gemfile).tap {|x| x.untaint if RUBY_VERSION < "2.7" }.expand_path
     end
 
     def default_lockfile
@@ -28,7 +28,7 @@ module Bundler
       case gemfile.basename.to_s
       when "gems.rb" then Pathname.new(gemfile.sub(/.rb$/, ".locked"))
       else Pathname.new("#{gemfile}.lock")
-      end.tap{|x| x.untaint if RUBY_VERSION < "2.7" }
+      end.tap {|x| x.untaint if RUBY_VERSION < "2.7" }
     end
 
     def default_bundle_dir
@@ -100,7 +100,7 @@ module Bundler
     #
     # @see {Bundler::PermissionError}
     def filesystem_access(path, action = :write, &block)
-      yield(path.dup.tap{|x| x.untaint if RUBY_VERSION < "2.7" })
+      yield(path.dup.tap {|x| x.untaint if RUBY_VERSION < "2.7" })
     rescue Errno::EACCES
       raise PermissionError.new(path, action)
     rescue Errno::EAGAIN
@@ -160,10 +160,10 @@ module Bundler
         " (was expecting #{old_deps.map(&:to_s)}, but the real spec has #{new_deps.map(&:to_s)})"
       raise APIResponseMismatchError,
         "Downloading #{spec.full_name} revealed dependencies not in the API or the lockfile (#{extra_deps.join(", ")})." \
-        "\nEither installing with `--full-index` or running `bundle update #{spec.name}` should fix the problem."
+        "\nRunning `bundle update #{spec.name}` should fix the problem."
     end
 
-    def pretty_dependency(dep, print_source = false)
+    def pretty_dependency(dep)
       msg = String.new(dep.name)
       msg << " (#{dep.requirement})" unless dep.requirement == Gem::Requirement.default
 
@@ -172,7 +172,6 @@ module Bundler
         msg << " " << platform_string if !platform_string.empty? && platform_string != Gem::Platform::RUBY
       end
 
-      msg << " from the `#{dep.source}` source" if print_source && dep.source
       msg
     end
 
@@ -236,7 +235,7 @@ module Bundler
 
     def search_up(*names)
       previous = nil
-      current  = File.expand_path(SharedHelpers.pwd).tap{|x| x.untaint if RUBY_VERSION < "2.7" }
+      current  = File.expand_path(SharedHelpers.pwd).tap {|x| x.untaint if RUBY_VERSION < "2.7" }
 
       until !File.directory?(current) || current == previous
         if ENV["BUNDLER_SPEC_RUN"]
@@ -274,10 +273,10 @@ module Bundler
 
     def set_bundle_variables
       # bundler exe & lib folders have same root folder, typical gem installation
-      exe_file = File.expand_path("../../../exe/bundle", __FILE__)
+      exe_file = File.expand_path("../../exe/bundle", __dir__)
 
       # for Ruby core repository testing
-      exe_file = File.expand_path("../../../libexec/bundle", __FILE__) unless File.exist?(exe_file)
+      exe_file = File.expand_path("../../libexec/bundle", __dir__) unless File.exist?(exe_file)
 
       # bundler is a default gem, exe path is separate
       exe_file = Bundler.rubygems.bin_path("bundler", "bundle", VERSION) unless File.exist?(exe_file)
@@ -285,6 +284,7 @@ module Bundler
       Bundler::SharedHelpers.set_env "BUNDLE_BIN_PATH", exe_file
       Bundler::SharedHelpers.set_env "BUNDLE_GEMFILE", find_gemfile.to_s
       Bundler::SharedHelpers.set_env "BUNDLER_VERSION", Bundler::VERSION
+      Bundler::SharedHelpers.set_env "BUNDLER_SETUP", File.expand_path("setup", __dir__) unless RUBY_VERSION < "2.7"
     end
 
     def set_path
@@ -309,7 +309,7 @@ module Bundler
     end
 
     def bundler_ruby_lib
-      resolve_path File.expand_path("../..", __FILE__)
+      File.expand_path("..", __dir__)
     end
 
     def clean_load_path
@@ -325,7 +325,7 @@ module Bundler
 
     def resolve_path(path)
       expanded = File.expand_path(path)
-      return expanded unless File.respond_to?(:realpath) && File.exist?(expanded)
+      return expanded unless File.exist?(expanded)
 
       File.realpath(expanded)
     end
diff --git a/lib/bundler/source.rb b/lib/bundler/source.rb
index 2a2b332cff..f7f5ea7865 100644
--- a/lib/bundler/source.rb
+++ b/lib/bundler/source.rb
@@ -15,13 +15,12 @@ module Bundler
       specs.unmet_dependency_names
     end
 
-    def version_message(spec)
+    def version_message(spec, locked_spec = nil)
       message = "#{spec.name} #{spec.version}"
       message += " (#{spec.platform})" if spec.platform != Gem::Platform::RUBY && !spec.platform.nil?
 
-      if Bundler.locked_gems
-        locked_spec = Bundler.locked_gems.specs.find {|s| s.name == spec.name }
-        locked_spec_version = locked_spec.version if locked_spec
+      if locked_spec
+        locked_spec_version = locked_spec.version
         if locked_spec_version && spec.version != locked_spec_version
           message += Bundler.ui.add_color(" (was #{locked_spec_version})", version_color(spec.version, locked_spec_version))
         end
@@ -101,7 +100,7 @@ module Bundler
     end
 
     def print_using_message(message)
-      if !message.include?("(was ") && Bundler.feature_flag.suppress_install_using_messages?
+      if !message.include?("(was ")
         Bundler.ui.debug message
       else
         Bundler.ui.info message
diff --git a/lib/bundler/source/git.rb b/lib/bundler/source/git.rb
index a41a2f23e9..adbce5fce4 100644
--- a/lib/bundler/source/git.rb
+++ b/lib/bundler/source/git.rb
@@ -19,7 +19,7 @@ module Bundler
         # Stringify options that could be set as symbols
         %w[ref branch tag revision].each {|k| options[k] = options[k].to_s if options[k] }
 
-        @uri        = options["uri"] || ""
+        @uri        = URINormalizer.normalize_suffix(options["uri"] || "", :trailing_slash => false)
         @safe_uri   = URICredentialsFilter.credential_filtered_uri(@uri)
         @branch     = options["branch"]
         @ref        = options["ref"] || options["branch"] || options["tag"]
@@ -46,6 +46,14 @@ module Bundler
         out << "  specs:\n"
       end
 
+      def to_gemfile
+        specifiers = %w[ref branch tag submodules glob].map do |opt|
+          "#{opt}: #{options[opt]}" if options[opt]
+        end
+
+        uri_with_specifiers(specifiers)
+      end
+
       def hash
         [self.class, uri, ref, branch, name, version, glob, submodules].hash
       end
@@ -59,28 +67,32 @@ module Bundler
 
       alias_method :==, :eql?
 
+      def include?(other)
+        other.is_a?(Git) && uri == other.uri &&
+          name == other.name &&
+          glob == other.glob &&
+          submodules == other.submodules
+      end
+
       def to_s
         begin
-          at = if local?
-            path
-          elsif user_ref = options["ref"]
-            if ref =~ /\A[a-z0-9]{4,}\z/i
-              shortref_for_display(user_ref)
-            else
-              user_ref
-            end
-          elsif ref
-            ref
-          else
-            git_proxy.branch
-          end
+          at = humanized_ref || current_branch
 
           rev = "at #{at}@#{shortref_for_display(revision)}"
         rescue GitError
           ""
         end
 
-        specifiers = [rev, glob_for_display].compact
+        uri_with_specifiers([rev, glob_for_display])
+      end
+
+      def identifier
+        uri_with_specifiers([humanized_ref, cached_revision, glob_for_display])
+      end
+
+      def uri_with_specifiers(specifiers)
+        specifiers.compact!
+
         suffix =
           if specifiers.any?
             " (#{specifiers.join(", ")})"
@@ -102,13 +114,7 @@ module Bundler
         @install_path ||= begin
           git_scope = "#{base_name}-#{shortref_for_path(revision)}"
 
-          path = Bundler.install_path.join(git_scope)
-
-          if !path.exist? && Bundler.requires_sudo?
-            Bundler.user_bundle_path.join(Bundler.ruby_scope).join(git_scope)
-          else
-            path
-          end
+          Bundler.install_path.join(git_scope)
         end
       end
 
@@ -132,7 +138,7 @@ module Bundler
         path = Pathname.new(path)
         path = path.expand_path(Bundler.root) unless path.relative?
 
-        unless options["branch"] || Bundler.settings[:disable_local_branch_check]
+        unless branch || Bundler.settings[:disable_local_branch_check]
           raise GitError, "Cannot use local override for #{name} at #{path} because " \
             ":branch is not specified in Gemfile. Specify a branch or run " \
             "`bundle config unset local.#{override_for(original_path)}` to remove the local override"
@@ -147,14 +153,14 @@ module Bundler
 
         # Create a new git proxy without the cached revision
         # so the Gemfile.lock always picks up the new revision.
-        @git_proxy = GitProxy.new(path, uri, ref)
+        @git_proxy = GitProxy.new(path, uri, options)
 
-        if git_proxy.branch != options["branch"] && !Bundler.settings[:disable_local_branch_check]
+        if current_branch != branch && !Bundler.settings[:disable_local_branch_check]
           raise GitError, "Local override for #{name} at #{path} is using branch " \
-            "#{git_proxy.branch} but Gemfile specifies #{options["branch"]}"
+            "#{current_branch} but Gemfile specifies #{branch}"
         end
 
-        changed = cached_revision && cached_revision != git_proxy.revision
+        changed = cached_revision && cached_revision != revision
 
         if !Bundler.settings[:disable_local_revision_check] && changed && !@unlocked && !git_proxy.contains?(cached_revision)
           raise GitError, "The Gemfile lock is pointing to revision #{shortref_for_display(cached_revision)} " \
@@ -179,9 +185,10 @@ module Bundler
       end
 
       def install(spec, options = {})
+        return if Bundler.settings[:no_install]
         force = options[:force]
 
-        print_using_message "Using #{version_message(spec)} from #{self}"
+        print_using_message "Using #{version_message(spec, options[:previous_spec])} from #{self}"
 
         if (requires_checkout? && !@copied) || force
           Bundler.ui.debug "  * Checking out revision: #{ref}"
@@ -219,13 +226,11 @@ module Bundler
       # across different projects, this cache will be shared.
       # When using local git repos, this is set to the local repo.
       def cache_path
-        @cache_path ||= begin
-          if Bundler.requires_sudo? || Bundler.feature_flag.global_gem_cache?
-            Bundler.user_cache
-          else
-            Bundler.bundle_path.join("cache", "bundler")
-          end.join("git", git_scope)
-        end
+        @cache_path ||= if Bundler.feature_flag.global_gem_cache?
+          Bundler.user_cache
+        else
+          Bundler.bundle_path.join("cache", "bundler")
+        end.join("git", git_scope)
       end
 
       def app_cache_dirname
@@ -236,6 +241,10 @@ module Bundler
         git_proxy.revision
       end
 
+      def current_branch
+        git_proxy.current_branch
+      end
+
       def allow_git_ops?
         @allow_remote || @allow_cached
       end
@@ -246,6 +255,20 @@ module Bundler
 
       private
 
+      def humanized_ref
+        if local?
+          path
+        elsif user_ref = options["ref"]
+          if /\A[a-z0-9]{4,}\z/i.match?(ref)
+            shortref_for_display(user_ref)
+          else
+            user_ref
+          end
+        elsif ref
+          ref
+        end
+      end
+
       def serialize_gemspecs_in(destination)
         destination = destination.expand_path(Bundler.root) if destination.relative?
         Dir["#{destination}/#{@glob}"].each do |spec_path|
@@ -299,7 +322,7 @@ module Bundler
       end
 
       def uri_hash
-        if uri =~ %r{^\w+://(\w+@)?}
+        if %r{^\w+://(\w+@)?}.match?(uri)
           # Downcase the domain component of the URI
           # and strip off a trailing slash, if one is present
           input = Bundler::URI.parse(uri).normalize.to_s.sub(%r{/$}, "")
@@ -321,7 +344,7 @@ module Bundler
       end
 
       def git_proxy
-        @git_proxy ||= GitProxy.new(cache_path, uri, ref, cached_revision, self)
+        @git_proxy ||= GitProxy.new(cache_path, uri, options, cached_revision, self)
       end
 
       def fetch
@@ -336,7 +359,7 @@ module Bundler
 
       def load_gemspec(file)
         stub = Gem::StubSpecification.gemspec_stub(file, install_path.parent, install_path.parent)
-        stub.full_gem_path = Pathname.new(file).dirname.expand_path(root).to_s.tap{|x| x.untaint if RUBY_VERSION < "2.7" }
+        stub.full_gem_path = Pathname.new(file).dirname.expand_path(root).to_s.tap {|x| x.untaint if RUBY_VERSION < "2.7" }
         StubSpecification.from_stub(stub)
       end
 
diff --git a/lib/bundler/source/git/git_proxy.rb b/lib/bundler/source/git/git_proxy.rb
index 745a7fe118..fdb738e52e 100644
--- a/lib/bundler/source/git/git_proxy.rb
+++ b/lib/bundler/source/git/git_proxy.rb
@@ -28,10 +28,10 @@ module Bundler
         def initialize(command, path, extra_info = nil)
           @command = command
 
-          msg = String.new
-          msg << "Git error: command `#{command}` in directory #{path} has failed."
+          msg = String.new("Git error: command `#{command}`")
+          msg << " in directory #{path}" if path
+          msg << " has failed."
           msg << "\n#{extra_info}" if extra_info
-          msg << "\nIf this error persists you could try removing the cache directory '#{path}'" if path.exist?
           super msg
         end
       end
@@ -47,24 +47,28 @@ module Bundler
       # All actions required by the Git source is encapsulated in this
       # object.
       class GitProxy
-        attr_accessor :path, :uri, :ref
+        attr_accessor :path, :uri, :branch, :tag, :ref, :explicit_ref
         attr_writer :revision
 
-        def initialize(path, uri, ref, revision = nil, git = nil)
+        def initialize(path, uri, options = {}, revision = nil, git = nil)
           @path     = path
           @uri      = uri
-          @ref      = ref
+          @branch   = options["branch"]
+          @tag      = options["tag"]
+          @ref      = options["ref"]
+          @explicit_ref = branch || tag || ref
           @revision = revision
           @git      = git
+          @commit_ref = nil
         end
 
         def revision
-          @revision ||= find_local_revision
+          @revision ||= allowed_with_path { find_local_revision }
         end
 
-        def branch
-          @branch ||= allowed_with_path do
-            git("rev-parse", "--abbrev-ref", "HEAD", :dir => path).strip
+        def current_branch
+          @current_branch ||= with_path do
+            git_local("rev-parse", "--abbrev-ref", "HEAD", :dir => path).strip
           end
         end
 
@@ -76,36 +80,26 @@ module Bundler
         end
 
         def version
-          git("--version").match(/(git version\s*)?((\.?\d+)+).*/)[2]
+          @version ||= full_version.match(/((\.?\d+)+).*/)[1]
         end
 
         def full_version
-          git("--version").sub("git version", "").strip
+          @full_version ||= git_local("--version").sub(/git version\s*/, "").strip
         end
 
         def checkout
-          return if path.exist? && has_revision_cached?
-          extra_ref = "#{ref}:#{ref}" if ref && ref.start_with?("refs/")
-
-          Bundler.ui.info "Fetching #{URICredentialsFilter.credential_filtered_uri(uri)}"
+          return if has_revision_cached?
 
-          configured_uri = configured_uri_for(uri).to_s
+          Bundler.ui.info "Fetching #{credential_filtered_uri}"
 
-          unless path.exist?
-            SharedHelpers.filesystem_access(path.dirname) do |p|
-              FileUtils.mkdir_p(p)
-            end
-            git_retry "clone", "--bare", "--no-hardlinks", "--quiet", "--", configured_uri, path.to_s
-            return unless extra_ref
-          end
+          extra_fetch_needed = clone_needs_extra_fetch?
+          unshallow_needed = clone_needs_unshallow?
+          return unless extra_fetch_needed || unshallow_needed
 
-          with_path do
-            git_retry(*["fetch", "--force", "--quiet", "--tags", "--", configured_uri, "refs/heads/*:refs/heads/*", extra_ref].compact, :dir => path)
-          end
+          git_remote_fetch(unshallow_needed ? ["--unshallow"] : depth_args)
         end
 
         def copy_to(destination, submodules = false)
-          # method 1
           unless File.exist?(destination.join(".git"))
             begin
               SharedHelpers.filesystem_access(destination.dirname) do |p|
@@ -114,7 +108,7 @@ module Bundler
               SharedHelpers.filesystem_access(destination) do |p|
                 FileUtils.rm_rf(p)
               end
-              git_retry "clone", "--no-checkout", "--quiet", path.to_s, destination.to_s
+              git "clone", "--no-checkout", "--quiet", path.to_s, destination.to_s
               File.chmod(((File.stat(destination).mode | 0o777) & ~File.umask), destination)
             rescue Errno::EEXIST => e
               file_path = e.message[%r{.*?((?:[a-zA-Z]:)?/.*)}, 1]
@@ -123,14 +117,10 @@ module Bundler
                 "this file and try again."
             end
           end
-          # method 2
-          git_retry "fetch", "--force", "--quiet", "--tags", path.to_s, :dir => destination
 
-          begin
-            git "reset", "--hard", @revision, :dir => destination
-          rescue GitCommandError => e
-            raise MissingGitRevisionError.new(e.command, destination, @revision, URICredentialsFilter.credential_filtered_uri(uri))
-          end
+          git "fetch", "--force", "--quiet", *extra_fetch_args, :dir => destination if @commit_ref
+
+          git "reset", "--hard", @revision, :dir => destination
 
           if submodules
             git_retry "submodule", "update", "--init", "--recursive", :dir => destination
@@ -142,14 +132,117 @@ module Bundler
 
         private
 
-        def git_null(*command, dir: nil)
-          check_allowed(command)
+        def git_remote_fetch(args)
+          command = ["fetch", "--force", "--quiet", "--no-tags", *args, "--", configured_uri, refspec].compact
+          command_with_no_credentials = check_allowed(command)
+
+          Bundler::Retry.new("`#{command_with_no_credentials}` at #{path}", [MissingGitRevisionError]).attempts do
+            out, err, status = capture(command, path)
+            return out if status.success?
+
+            if err.include?("couldn't find remote ref") || err.include?("not our ref")
+              raise MissingGitRevisionError.new(command_with_no_credentials, path, commit || explicit_ref, credential_filtered_uri)
+            else
+              raise GitCommandError.new(command_with_no_credentials, path, err)
+            end
+          end
+        end
+
+        def clone_needs_extra_fetch?
+          return true if path.exist?
+
+          SharedHelpers.filesystem_access(path.dirname) do |p|
+            FileUtils.mkdir_p(p)
+          end
+
+          command = ["clone", "--bare", "--no-hardlinks", "--quiet", *extra_clone_args, "--", configured_uri, path.to_s]
+          command_with_no_credentials = check_allowed(command)
+
+          Bundler::Retry.new("`#{command_with_no_credentials}`", [MissingGitRevisionError]).attempts do
+            _, err, status = capture(command, nil)
+            return extra_ref if status.success?
+
+            if err.include?("Could not find remote branch") || # git up to 2.49
+               err.include?("Remote branch #{branch_option} not found") # git 2.49 or higher
+              raise MissingGitRevisionError.new(command_with_no_credentials, nil, explicit_ref, credential_filtered_uri)
+            else
+              raise GitCommandError.new(command_with_no_credentials, path, err)
+            end
+          end
+        end
 
-          out, status = SharedHelpers.with_clean_git_env do
-            capture_and_ignore_stderr(*capture3_args_for(command, dir))
+        def clone_needs_unshallow?
+          return false unless path.join("shallow").exist?
+          return true if full_clone?
+
+          @revision && @revision != head_revision
+        end
+
+        def extra_ref
+          return false if not_pinned?
+          return true unless full_clone?
+
+          ref.start_with?("refs/")
+        end
+
+        def depth
+          return @depth if defined?(@depth)
+
+          @depth = if !supports_fetching_unreachable_refs?
+            nil
+          elsif not_pinned? || pinned_to_full_sha?
+            1
+          elsif ref.include?("~")
+            parsed_depth = ref.split("~").last
+            parsed_depth.to_i + 1
           end
+        end
+
+        def refspec
+          if commit
+            @commit_ref = "refs/#{commit}-sha"
+            return "#{commit}:#{@commit_ref}"
+          end
+
+          reference = fully_qualified_ref
+
+          reference ||= if ref.include?("~")
+            ref.split("~").first
+          elsif ref.start_with?("refs/")
+            ref
+          else
+            "refs/*"
+          end
+
+          "#{reference}:#{reference}"
+        end
+
+        def commit
+          @commit ||= pinned_to_full_sha? ? ref : @revision
+        end
+
+        def fully_qualified_ref
+          if branch
+            "refs/heads/#{branch}"
+          elsif tag
+            "refs/tags/#{tag}"
+          elsif ref.nil?
+            "refs/heads/#{current_branch}"
+          end
+        end
+
+        def not_pinned?
+          branch_option || ref.nil?
+        end
+
+        def pinned_to_full_sha?
+          ref =~ /\A\h{40}\z/
+        end
 
-          [URICredentialsFilter.credential_filtered_string(out, uri), status]
+        def git_null(*command, dir: nil)
+          check_allowed(command)
+
+          capture(command, dir, :ignore_err => true)
         end
 
         def git_retry(*command, dir: nil)
@@ -161,51 +254,64 @@ module Bundler
         end
 
         def git(*command, dir: nil)
-          command_with_no_credentials = check_allowed(command)
-
-          out, status = SharedHelpers.with_clean_git_env do
-            capture_and_filter_stderr(*capture3_args_for(command, dir))
+          run_command(*command, :dir => dir) do |unredacted_command|
+            check_allowed(unredacted_command)
           end
+        end
 
-          filtered_out = URICredentialsFilter.credential_filtered_string(out, uri)
-
-          raise GitCommandError.new(command_with_no_credentials, dir || SharedHelpers.pwd, filtered_out) unless status.success?
-
-          filtered_out
+        def git_local(*command, dir: nil)
+          run_command(*command, :dir => dir) do |unredacted_command|
+            redact_and_check_presence(unredacted_command)
+          end
         end
 
         def has_revision_cached?
-          return unless @revision
-          with_path { git("cat-file", "-e", @revision, :dir => path) }
+          return unless @revision && path.exist?
+          git("cat-file", "-e", @revision, :dir => path)
           true
         rescue GitError
           false
         end
 
-        def remove_cache
-          FileUtils.rm_rf(path)
+        def find_local_revision
+          return head_revision if explicit_ref.nil?
+
+          find_revision_for(explicit_ref)
         end
 
-        def find_local_revision
-          allowed_with_path do
-            git("rev-parse", "--verify", ref || "HEAD", :dir => path).strip
-          end
+        def head_revision
+          verify("HEAD")
+        end
+
+        def find_revision_for(reference)
+          verify(reference)
         rescue GitCommandError => e
-          raise MissingGitRevisionError.new(e.command, path, ref, URICredentialsFilter.credential_filtered_uri(uri))
+          raise MissingGitRevisionError.new(e.command, path, reference, credential_filtered_uri)
         end
 
-        # Adds credentials to the URI as Fetcher#configured_uri_for does
-        def configured_uri_for(uri)
-          if /https?:/ =~ uri
+        def verify(reference)
+          git("rev-parse", "--verify", reference, :dir => path).strip
+        end
+
+        # Adds credentials to the URI
+        def configured_uri
+          if /https?:/.match?(uri)
             remote = Bundler::URI(uri)
             config_auth = Bundler.settings[remote.to_s] || Bundler.settings[remote.host]
             remote.userinfo ||= config_auth
             remote.to_s
+          elsif File.exist?(uri)
+            "file://#{uri}"
           else
-            uri
+            uri.to_s
           end
         end
 
+        # Removes credentials from the URI
+        def credential_filtered_uri
+          URICredentialsFilter.credential_filtered_uri(uri)
+        end
+
         def allow?
           allowed = @git ? @git.allow_git_ops? : true
 
@@ -225,23 +331,41 @@ module Bundler
         end
 
         def check_allowed(command)
-          require "shellwords"
-          command_with_no_credentials = URICredentialsFilter.credential_filtered_string("git #{command.shelljoin}", uri)
+          command_with_no_credentials = redact_and_check_presence(command)
           raise GitNotAllowedError.new(command_with_no_credentials) unless allow?
           command_with_no_credentials
         end
 
-        def capture_and_filter_stderr(*cmd)
-          require "open3"
-          return_value, captured_err, status = Open3.capture3(*cmd)
-          Bundler.ui.warn URICredentialsFilter.credential_filtered_string(captured_err, uri) unless captured_err.empty?
-          [return_value, status]
+        def redact_and_check_presence(command)
+          raise GitNotInstalledError.new unless Bundler.git_present?
+
+          require "shellwords"
+          URICredentialsFilter.credential_filtered_string("git #{command.shelljoin}", uri)
+        end
+
+        def run_command(*command, dir: nil)
+          command_with_no_credentials = yield(command)
+
+          out, err, status = capture(command, dir)
+
+          raise GitCommandError.new(command_with_no_credentials, dir || SharedHelpers.pwd, err) unless status.success?
+
+          Bundler.ui.warn err unless err.empty?
+
+          out
         end
 
-        def capture_and_ignore_stderr(*cmd)
-          require "open3"
-          return_value, _, status = Open3.capture3(*cmd)
-          [return_value, status]
+        def capture(cmd, dir, ignore_err: false)
+          SharedHelpers.with_clean_git_env do
+            require "open3"
+            out, err, status = Open3.capture3(*capture3_args_for(cmd, dir))
+
+            filtered_out = URICredentialsFilter.credential_filtered_string(out, uri)
+            return [filtered_out, status] if ignore_err
+
+            filtered_err = URICredentialsFilter.credential_filtered_string(err, uri)
+            [filtered_out, filtered_err, status]
+          end
         end
 
         def capture3_args_for(cmd, dir)
@@ -254,9 +378,53 @@ module Bundler
           end
         end
 
+        def extra_clone_args
+          args = depth_args
+          return [] if args.empty?
+
+          args += ["--single-branch"]
+          args.unshift("--no-tags") if supports_cloning_with_no_tags?
+
+          # If there's a locked revision, no need to clone any specific branch
+          # or tag, since we will end up checking out that locked revision
+          # anyways.
+          return args if @revision
+
+          args += ["--branch", branch_option] if branch_option
+          args
+        end
+
+        def depth_args
+          return [] if full_clone?
+
+          ["--depth", depth.to_s]
+        end
+
+        def extra_fetch_args
+          extra_args = [path.to_s, *depth_args]
+          extra_args.push(@commit_ref)
+          extra_args
+        end
+
+        def branch_option
+          branch || tag
+        end
+
+        def full_clone?
+          depth.nil?
+        end
+
         def supports_minus_c?
           @supports_minus_c ||= Gem::Version.new(version) >= Gem::Version.new("1.8.5")
         end
+
+        def supports_fetching_unreachable_refs?
+          @supports_fetching_unreachable_refs ||= Gem::Version.new(version) >= Gem::Version.new("2.5.0")
+        end
+
+        def supports_cloning_with_no_tags?
+          @supports_cloning_with_no_tags ||= Gem::Version.new(version) >= Gem::Version.new("2.14.0-rc0")
+        end
       end
     end
   end
diff --git a/lib/bundler/source/metadata.rb b/lib/bundler/source/metadata.rb
index 8bdbaa5527..593da6d1a7 100644
--- a/lib/bundler/source/metadata.rb
+++ b/lib/bundler/source/metadata.rb
@@ -5,7 +5,7 @@ module Bundler
     class Metadata < Source
       def specs
         @specs ||= Index.build do |idx|
-          idx << Gem::Specification.new("Ruby\0", RubyVersion.system.to_gem_version_with_patchlevel)
+          idx << Gem::Specification.new("Ruby\0", Gem.ruby_version)
           idx << Gem::Specification.new("RubyGems\0", Gem::VERSION) do |s|
             s.required_rubygems_version = Gem::Requirement.default
           end
@@ -15,14 +15,13 @@ module Bundler
             s.version  = VERSION
             s.license  = "MIT"
             s.platform = Gem::Platform::RUBY
-            s.source   = self
             s.authors  = ["bundler team"]
             s.bindir   = "exe"
             s.homepage = "https://bundler.io"
             s.summary  = "The best way to manage your application's dependencies"
             s.executables = %w[bundle]
             # can't point to the actual gemspec or else the require paths will be wrong
-            s.loaded_from = File.expand_path("..", __FILE__)
+            s.loaded_from = __dir__
           end
 
           if local_spec = Bundler.rubygems.find_bundler(VERSION)
diff --git a/lib/bundler/source/path.rb b/lib/bundler/source/path.rb
index 01f89b204d..bdfcf8274a 100644
--- a/lib/bundler/source/path.rb
+++ b/lib/bundler/source/path.rb
@@ -11,7 +11,7 @@ module Bundler
 
       protected :original_path
 
-      DEFAULT_GLOB = "{,*,*/*}.gemspec".freeze
+      DEFAULT_GLOB = "{,*,*/*}.gemspec"
 
       def initialize(options)
         @options = options.dup
@@ -82,7 +82,7 @@ module Bundler
       end
 
       def install(spec, options = {})
-        using_message = "Using #{version_message(spec)} from #{self}"
+        using_message = "Using #{version_message(spec, options[:previous_spec])} from #{self}"
         using_message += " and installing its executables" unless spec.executables.empty?
         print_using_message using_message
         generate_bin(spec, :disable_extensions => true)
@@ -224,13 +224,13 @@ module Bundler
 
         # Some gem authors put absolute paths in their gemspec
         # and we have to save them from themselves
-        spec.files = spec.files.map do |p|
-          next p unless p =~ /\A#{Pathname::SEPARATOR_PAT}/
-          next if File.directory?(p)
+        spec.files = spec.files.map do |path|
+          next path unless /\A#{Pathname::SEPARATOR_PAT}/.match?(path)
+          next if File.directory?(path)
           begin
-            Pathname.new(p).relative_path_from(gem_dir).to_s
+            Pathname.new(path).relative_path_from(gem_dir).to_s
           rescue ArgumentError
-            p
+            path
           end
         end.compact
 
diff --git a/lib/bundler/source/path/installer.rb b/lib/bundler/source/path/installer.rb
index a70973bde7..0af28fe770 100644
--- a/lib/bundler/source/path/installer.rb
+++ b/lib/bundler/source/path/installer.rb
@@ -18,13 +18,7 @@ module Bundler
           @build_args         = options[:build_args] || Bundler.rubygems.build_args
           @gem_bin_dir        = "#{Bundler.rubygems.gem_dir}/bin"
           @disable_extensions = options[:disable_extensions]
-
-          if Bundler.requires_sudo?
-            @tmp_dir = Bundler.tmp(spec.full_name).to_s
-            @bin_dir = "#{@tmp_dir}/bin"
-          else
-            @bin_dir = @gem_bin_dir
-          end
+          @bin_dir = @gem_bin_dir
         end
 
         def post_install
@@ -38,25 +32,10 @@ module Bundler
           generate_bin unless spec.executables.empty?
 
           run_hooks(:post_install)
-        ensure
-          Bundler.rm_rf(@tmp_dir) if Bundler.requires_sudo?
         end
 
         private
 
-        def generate_bin
-          super
-
-          if Bundler.requires_sudo?
-            SharedHelpers.filesystem_access(@gem_bin_dir) do |p|
-              Bundler.mkdir_p(p)
-            end
-            spec.executables.each do |exe|
-              Bundler.sudo "cp -R #{@bin_dir}/#{exe} #{@gem_bin_dir}"
-            end
-          end
-        end
-
         def run_hooks(type)
           hooks_meth = "#{type}_hooks"
           return unless Gem.respond_to?(hooks_meth)
diff --git a/lib/bundler/source/rubygems.rb b/lib/bundler/source/rubygems.rb
index 8bc3aa17e9..af57acbbc2 100644
--- a/lib/bundler/source/rubygems.rb
+++ b/lib/bundler/source/rubygems.rb
@@ -7,12 +7,10 @@ module Bundler
     class Rubygems < Source
       autoload :Remote, File.expand_path("rubygems/remote", __dir__)
 
-      # Use the API when installing less than X gems
-      API_REQUEST_LIMIT = 500
       # Ask for X gems per API request
       API_REQUEST_SIZE = 50
 
-      attr_reader :remotes, :caches
+      attr_reader :remotes
 
       def initialize(options = {})
         @options = options
@@ -21,11 +19,14 @@ module Bundler
         @allow_remote = false
         @allow_cached = false
         @allow_local = options["allow_local"] || false
-        @caches = [cache_path, *Bundler.rubygems.gem_cache]
 
         Array(options["remotes"]).reverse_each {|r| add_remote(r) }
       end
 
+      def caches
+        @caches ||= [cache_path, *Bundler.rubygems.gem_cache]
+      end
+
       def local_only!
         @specs = nil
         @allow_local = true
@@ -122,6 +123,7 @@ module Bundler
         end
       end
       alias_method :name, :identifier
+      alias_method :to_gemfile, :identifier
 
       def specs
         @specs ||= begin
@@ -135,110 +137,78 @@ module Bundler
         end
       end
 
-      def install(spec, opts = {})
-        force = opts[:force]
-        ensure_builtin_gems_cached = opts[:ensure_builtin_gems_cached]
+      def install(spec, options = {})
+        force = options[:force]
+        ensure_builtin_gems_cached = options[:ensure_builtin_gems_cached]
 
-        if ensure_builtin_gems_cached && spec.default_gem?
-          if !cached_path(spec)
-            cached_built_in_gem(spec) unless spec.remote
-            force = true
-          else
-            spec.loaded_from = loaded_from(spec)
-          end
+        if ensure_builtin_gems_cached && spec.default_gem? && !cached_path(spec)
+          cached_built_in_gem(spec) unless spec.remote
+          force = true
         end
 
         if installed?(spec) && !force
-          print_using_message "Using #{version_message(spec)}"
+          print_using_message "Using #{version_message(spec, options[:previous_spec])}"
           return nil # no post-install message
         end
 
-        # Download the gem to get the spec, because some specs that are returned
-        # by rubygems.org are broken and wrong.
         if spec.remote
           # Check for this spec from other sources
-          uris = [spec.remote.anonymized_uri]
-          uris += remotes_for_spec(spec).map(&:anonymized_uri)
-          uris.uniq!
+          uris = [spec.remote, *remotes_for_spec(spec)].map(&:anonymized_uri).uniq
           Installer.ambiguous_gems << [spec.name, *uris] if uris.length > 1
+        end
+
+        path = fetch_gem_if_possible(spec, options[:previous_spec])
+        raise GemNotFound, "Could not find #{spec.file_name} for installation" unless path
+
+        return if Bundler.settings[:no_install]
+
+        install_path = rubygems_dir
+        bin_path     = Bundler.system_bindir
+
+        require_relative "../rubygems_gem_installer"
 
-          path = fetch_gem(spec)
-          begin
-            s = Bundler.rubygems.spec_from_gem(path, Bundler.settings["trust-policy"])
-            spec.__swap__(s)
+        installer = Bundler::RubyGemsGemInstaller.at(
+          path,
+          :security_policy => Bundler.rubygems.security_policies[Bundler.settings["trust-policy"]],
+          :install_dir => install_path.to_s,
+          :bin_dir => bin_path.to_s,
+          :ignore_dependencies => true,
+          :wrappers => true,
+          :env_shebang => true,
+          :build_args => options[:build_args],
+          :bundler_expected_checksum => spec.respond_to?(:checksum) && spec.checksum,
+          :bundler_extension_cache_path => extension_cache_path(spec)
+        )
+
+        if spec.remote
+          s = begin
+            installer.spec
           rescue Gem::Package::FormatError
             Bundler.rm_rf(path)
             raise
+          rescue Gem::Security::Exception => e
+            raise SecurityError,
+             "The gem #{File.basename(path, ".gem")} can't be installed because " \
+             "the security policy didn't allow it, with the message: #{e.message}"
           end
+
+          spec.__swap__(s)
         end
 
-        unless Bundler.settings[:no_install]
-          message = "Installing #{version_message(spec)}"
-          message += " with native extensions" if spec.extensions.any?
-          Bundler.ui.confirm message
+        message = "Installing #{version_message(spec, options[:previous_spec])}"
+        message += " with native extensions" if spec.extensions.any?
+        Bundler.ui.confirm message
 
-          path = cached_gem(spec)
-          raise GemNotFound, "Could not find #{spec.file_name} for installation" unless path
-          if requires_sudo?
-            install_path = Bundler.tmp(spec.full_name)
-            bin_path     = install_path.join("bin")
-          else
-            install_path = rubygems_dir
-            bin_path     = Bundler.system_bindir
-          end
+        installed_spec = installer.install
 
-          Bundler.mkdir_p bin_path, :no_sudo => true unless spec.executables.empty? || Bundler.rubygems.provides?(">= 2.7.5")
-
-          require_relative "../rubygems_gem_installer"
-
-          installed_spec = Bundler::RubyGemsGemInstaller.at(
-            path,
-            :install_dir         => install_path.to_s,
-            :bin_dir             => bin_path.to_s,
-            :ignore_dependencies => true,
-            :wrappers            => true,
-            :env_shebang         => true,
-            :build_args          => opts[:build_args],
-            :bundler_expected_checksum => spec.respond_to?(:checksum) && spec.checksum,
-            :bundler_extension_cache_path => extension_cache_path(spec)
-          ).install
-          spec.full_gem_path = installed_spec.full_gem_path
-
-          # SUDO HAX
-          if requires_sudo?
-            Bundler.rubygems.repository_subdirectories.each do |name|
-              src = File.join(install_path, name, "*")
-              dst = File.join(rubygems_dir, name)
-              if name == "extensions" && Dir.glob(src).any?
-                src = File.join(src, "*/*")
-                ext_src = Dir.glob(src).first
-                ext_src.gsub!(src[0..-6], "")
-                dst = File.dirname(File.join(dst, ext_src))
-              end
-              SharedHelpers.filesystem_access(dst) do |p|
-                Bundler.mkdir_p(p)
-              end
-              Bundler.sudo "cp -R #{src} #{dst}" if Dir[src].any?
-            end
-
-            spec.executables.each do |exe|
-              SharedHelpers.filesystem_access(Bundler.system_bindir) do |p|
-                Bundler.mkdir_p(p)
-              end
-              Bundler.sudo "cp -R #{install_path}/bin/#{exe} #{Bundler.system_bindir}/"
-            end
-          end
-          installed_spec.loaded_from = loaded_from(spec)
-        end
-        spec.loaded_from = loaded_from(spec)
+        spec.full_gem_path = installed_spec.full_gem_path
+        spec.loaded_from = installed_spec.loaded_from
 
         spec.post_install_message
-      ensure
-        Bundler.rm_rf(install_path) if requires_sudo?
       end
 
       def cache(spec, custom_path = nil)
-        cached_path = cached_gem(spec)
+        cached_path = Bundler.settings[:cache_all_platforms] ? fetch_gem_if_possible(spec) : cached_gem(spec)
         raise GemNotFound, "Missing gem file '#{spec.file_name}'." unless cached_path
         return if File.dirname(cached_path) == Bundler.app_cache.to_s
         Bundler.ui.info "  * #{File.basename(cached_path)}"
@@ -324,7 +294,7 @@ module Bundler
       end
 
       def dependency_api_available?
-        api_fetchers.any?
+        @allow_remote && api_fetchers.any?
       end
 
       protected
@@ -348,10 +318,6 @@ module Bundler
         end
       end
 
-      def loaded_from(spec)
-        "#{rubygems_dir}/specifications/#{spec.full_name}.gemspec"
-      end
-
       def cached_gem(spec)
         if spec.default_gem?
           cached_built_in_gem(spec)
@@ -362,15 +328,18 @@ module Bundler
 
       def cached_path(spec)
         global_cache_path = download_cache_path(spec)
-        @caches << global_cache_path if global_cache_path
+        caches << global_cache_path if global_cache_path
 
-        possibilities = @caches.map {|p| "#{p}/#{spec.file_name}" }
+        possibilities = caches.map {|p| package_path(p, spec) }
         possibilities.find {|p| File.exist?(p) }
       end
 
+      def package_path(cache_path, spec)
+        "#{cache_path}/#{spec.file_name}"
+      end
+
       def normalize_uri(uri)
-        uri = uri.to_s
-        uri = "#{uri}/" unless uri =~ %r{/$}
+        uri = URINormalizer.normalize_suffix(uri.to_s)
         require_relative "../vendored_uri"
         uri = Bundler::URI(uri)
         raise ArgumentError, "The source must be an absolute URI. For example:\n" \
@@ -413,7 +382,6 @@ module Bundler
           idx = @allow_local ? installed_specs.dup : Index.new
 
           Dir["#{cache_path}/*.gem"].each do |gemfile|
-            next if gemfile =~ /^bundler\-[\d\.]+?\.gem/
             s ||= Bundler.rubygems.spec_from_gem(gemfile)
             s.source = self
             idx << s
@@ -434,12 +402,11 @@ module Bundler
           # gather lists from non-api sites
           fetch_names(index_fetchers, nil, idx, false)
 
-          # because ensuring we have all the gems we need involves downloading
-          # the gemspecs of those gems, if the non-api sites contain more than
-          # about 500 gems, we treat all sites as non-api for speed.
-          allow_api = idx.size < API_REQUEST_LIMIT && dependency_names.size < API_REQUEST_LIMIT
-          Bundler.ui.debug "Need to query more than #{API_REQUEST_LIMIT} gems." \
-            " Downloading full index instead..." unless allow_api
+          # legacy multi-remote sources need special logic to figure out
+          # dependency names and that logic can be very costly if one remote
+          # uses the dependency API but others don't. So use full indexes
+          # consistently in that particular case.
+          allow_api = !multiple_remotes?
 
           fetch_names(api_fetchers, allow_api && dependency_names, idx, false)
         end
@@ -458,48 +425,35 @@ module Bundler
         end
       end
 
-      def fetch_gem(spec)
-        return false unless spec.remote
+      def fetch_gem_if_possible(spec, previous_spec = nil)
+        if spec.remote
+          fetch_gem(spec, previous_spec)
+        else
+          cached_gem(spec)
+        end
+      end
 
+      def fetch_gem(spec, previous_spec = nil)
         spec.fetch_platform
 
         cache_path = download_cache_path(spec) || default_cache_path_for(rubygems_dir)
-        gem_path = "#{cache_path}/#{spec.file_name}"
+        gem_path = package_path(cache_path, spec)
+        return gem_path if File.exist?(gem_path)
 
-        if requires_sudo?
-          download_path = Bundler.tmp(spec.full_name)
-          download_cache_path = default_cache_path_for(download_path)
-        else
-          download_cache_path = cache_path
-        end
-
-        SharedHelpers.filesystem_access(download_cache_path) do |p|
+        SharedHelpers.filesystem_access(cache_path) do |p|
           FileUtils.mkdir_p(p)
         end
-        download_gem(spec, download_cache_path)
-
-        if requires_sudo?
-          SharedHelpers.filesystem_access(cache_path) do |p|
-            Bundler.mkdir_p(p)
-          end
-          Bundler.sudo "mv #{download_cache_path}/#{spec.file_name} #{gem_path}"
-        end
+        download_gem(spec, cache_path, previous_spec)
 
         gem_path
-      ensure
-        Bundler.rm_rf(download_path) if requires_sudo?
       end
 
       def installed?(spec)
         installed_specs[spec].any? && !spec.deleted_gem?
       end
 
-      def requires_sudo?
-        Bundler.requires_sudo?
-      end
-
       def rubygems_dir
-        Bundler.rubygems.gem_dir
+        Bundler.bundle_path
       end
 
       def default_cache_path_for(dir)
@@ -521,9 +475,12 @@ module Bundler
       # @param  [String] download_cache_path
       #         the local directory the .gem will end up in.
       #
-      def download_gem(spec, download_cache_path)
+      # @param  [Specification] previous_spec
+      #         the spec previously locked
+      #
+      def download_gem(spec, download_cache_path, previous_spec = nil)
         uri = spec.remote.uri
-        Bundler.ui.confirm("Fetching #{version_message(spec)}")
+        Bundler.ui.confirm("Fetching #{version_message(spec, previous_spec)}")
         Bundler.rubygems.download_gem(spec, uri, download_cache_path)
       end
 
diff --git a/lib/bundler/source_list.rb b/lib/bundler/source_list.rb
index a4773397c7..4419695b7f 100644
--- a/lib/bundler/source_list.rb
+++ b/lib/bundler/source_list.rb
@@ -157,11 +157,17 @@ module Bundler
     end
 
     def map_sources(replacement_sources)
-      [@rubygems_sources, @path_sources, @git_sources, @plugin_sources].map do |sources|
+      rubygems, git, plugin = [@rubygems_sources, @git_sources, @plugin_sources].map do |sources|
         sources.map do |source|
           replacement_sources.find {|s| s == source } || source
         end
       end
+
+      path = @path_sources.map do |source|
+        replacement_sources.find {|s| s == (source.is_a?(Source::Gemspec) ? source.as_path_source : source) } || source
+      end
+
+      [rubygems, path, git, plugin]
     end
 
     def global_replacement_source(replacement_sources)
@@ -202,7 +208,7 @@ module Bundler
     def warn_on_git_protocol(source)
       return if Bundler.settings["git.allow_insecure"]
 
-      if source.uri =~ /^git\:/
+      if /^git\:/.match?(source.uri)
         Bundler.ui.warn "The git source `#{source.uri}` uses the `git` protocol, " \
           "which transmits data without encryption. Disable this warning with " \
           "`bundle config set --local git.allow_insecure true`, or switch to the `https` " \
diff --git a/lib/bundler/spec_set.rb b/lib/bundler/spec_set.rb
index a19d18388a..21630e3a3e 100644
--- a/lib/bundler/spec_set.rb
+++ b/lib/bundler/spec_set.rb
@@ -7,40 +7,49 @@ module Bundler
     include Enumerable
     include TSort
 
-    def initialize(specs)
+    attr_reader :incomplete_specs
+
+    def initialize(specs, incomplete_specs = [])
       @specs = specs
+      @incomplete_specs = incomplete_specs
     end
 
-    def for(dependencies, check = false, match_current_platform = false)
-      handled = []
-      deps = dependencies.dup
+    def for(dependencies, check = false, platforms = [nil])
+      handled = ["bundler"].product(platforms).map {|k| [k, true] }.to_h
+      deps = dependencies.product(platforms)
       specs = []
 
       loop do
         break unless dep = deps.shift
-        next if handled.any?{|d| d.name == dep.name && (match_current_platform || d.__platform == dep.__platform) } || dep.name == "bundler"
 
-        handled << dep
+        name = dep[0].name
+        platform = dep[1]
+        incomplete = false
+
+        key = [name, platform]
+        next if handled.key?(key)
+
+        handled[key] = true
 
-        specs_for_dep = spec_for_dependency(dep, match_current_platform)
+        specs_for_dep = specs_for_dependency(*dep)
         if specs_for_dep.any?
-          match_current_platform ? specs += specs_for_dep : specs |= specs_for_dep
+          specs.concat(specs_for_dep)
 
           specs_for_dep.first.dependencies.each do |d|
             next if d.type == :development
-            d = DepProxy.get_proxy(d, dep.__platform) unless match_current_platform
-            deps << d
+            incomplete = true if d.name != "bundler" && lookup[d.name].empty?
+            deps << [d, dep[1]]
           end
-        elsif check
-          return false
+        else
+          incomplete = true
         end
-      end
 
-      if spec = lookup["bundler"].first
-        specs << spec
+        if incomplete && check
+          @incomplete_specs += lookup[name].any? ? lookup[name] : [LazySpecification.new(name, nil, nil)]
+        end
       end
 
-      check ? true : specs
+      specs.uniq
     end
 
     def [](key)
@@ -54,6 +63,12 @@ module Bundler
       @sorted = nil
     end
 
+    def delete(specs)
+      specs.each {|spec| @specs.delete(spec) }
+      @lookup = nil
+      @sorted = nil
+    end
+
     def sort!
       self
     end
@@ -67,14 +82,9 @@ module Bundler
     end
 
     def materialize(deps)
-      materialized = self.for(deps, false, true)
+      materialized = self.for(deps, true)
 
-      materialized.map! do |s|
-        next s unless s.is_a?(LazySpecification)
-        s.source.local!
-        s.__materialize__ || s
-      end
-      SpecSet.new(materialized)
+      SpecSet.new(materialized, incomplete_specs)
     end
 
     # Materialize for all the specs in the spec set, regardless of what platform they're for
@@ -83,14 +93,23 @@ module Bundler
     def materialized_for_all_platforms
       @specs.map do |s|
         next s unless s.is_a?(LazySpecification)
-        s.source.local!
         s.source.remote!
-        spec = s.__materialize__
+        spec = s.materialize_for_installation
         raise GemNotFound, "Could not find #{s.full_name} in any of the sources" unless spec
         spec
       end
     end
 
+    def incomplete_ruby_specs?(deps)
+      return false if @specs.empty?
+
+      @incomplete_specs = []
+
+      self.for(deps, true, [Gem::Platform::RUBY])
+
+      @incomplete_specs.any?
+    end
+
     def missing_specs
       @specs.select {|s| s.is_a?(LazySpecification) }
     end
@@ -105,10 +124,20 @@ module Bundler
       SpecSet.new(arr)
     end
 
+    def -(other)
+      SpecSet.new(to_a - other.to_a)
+    end
+
     def find_by_name_and_platform(name, platform)
       @specs.detect {|spec| spec.name == name && spec.match_platform(platform) }
     end
 
+    def delete_by_name(name)
+      @specs.reject! {|spec| spec.name == name }
+      @lookup = nil
+      @sorted = nil
+    end
+
     def what_required(spec)
       unless req = find {|s| s.dependencies.any? {|d| d.type == :runtime && d.name == spec.name } }
         return [spec]
@@ -146,7 +175,7 @@ module Bundler
         cgems = extract_circular_gems(error)
         raise CyclicDependencyError, "Your bundle requires gems that depend" \
           " on each other, creating an infinite loop. Please remove either" \
-          " gem '#{cgems[1]}' or gem '#{cgems[0]}' and try again."
+          " gem '#{cgems[0]}' or gem '#{cgems[1]}' and try again."
       end
     end
 
@@ -157,7 +186,7 @@ module Bundler
     def lookup
       @lookup ||= begin
         lookup = Hash.new {|h, k| h[k] = [] }
-        Index.sort_specs(@specs).reverse_each do |s|
+        @specs.each do |s|
           lookup[s.name] << s
         end
         lookup
@@ -169,13 +198,12 @@ module Bundler
       @specs.sort_by(&:name).each {|s| yield s }
     end
 
-    def spec_for_dependency(dep, match_current_platform)
-      specs_for_platforms = lookup[dep.name]
-      if match_current_platform
-        GemHelpers.select_best_platform_match(specs_for_platforms.select{|s| Gem::Platform.match_spec?(s) }, Bundler.local_platform)
-      else
-        GemHelpers.select_best_platform_match(specs_for_platforms, dep.__platform)
-      end
+    def specs_for_dependency(dep, platform)
+      specs_for_name = lookup[dep.name]
+      target_platform = dep.force_ruby_platform ? Gem::Platform::RUBY : (platform || Bundler.local_platform)
+      matching_specs = GemHelpers.select_best_platform_match(specs_for_name, target_platform)
+      matching_specs.map!(&:materialize_for_installation).compact! if platform.nil?
+      matching_specs
     end
 
     def tsort_each_child(s)
diff --git a/lib/bundler/stub_specification.rb b/lib/bundler/stub_specification.rb
index fa071901e5..88a4257fa4 100644
--- a/lib/bundler/stub_specification.rb
+++ b/lib/bundler/stub_specification.rb
@@ -64,9 +64,11 @@ module Bundler
     end
 
     def full_gem_path
-      # deleted gems can have their stubs return nil, so in that case grab the
-      # expired path from the full spec
-      stub.full_gem_path || method_missing(:full_gem_path)
+      stub.full_gem_path
+    end
+
+    def full_gem_path=(path)
+      stub.full_gem_path = path
     end
 
     def full_require_paths
diff --git a/lib/bundler/templates/Executable b/lib/bundler/templates/Executable
index 3e8d5b317a..9ff6f00898 100644
--- a/lib/bundler/templates/Executable
+++ b/lib/bundler/templates/Executable
@@ -8,14 +8,12 @@
 # this file is here to facilitate running it.
 #
 
-require "pathname"
-ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../<%= relative_gemfile_path %>",
-  Pathname.new(__FILE__).realpath)
+ENV["BUNDLE_GEMFILE"] ||= File.expand_path("<%= relative_gemfile_path %>", __dir__)
 
-bundle_binstub = File.expand_path("../bundle", __FILE__)
+bundle_binstub = File.expand_path("bundle", __dir__)
 
 if File.file?(bundle_binstub)
-  if File.read(bundle_binstub, 300) =~ /This file was generated by Bundler/
+  if File.read(bundle_binstub, 300).include?("This file was generated by Bundler")
     load(bundle_binstub)
   else
     abort("Your `bin/bundle` was not generated by Bundler, so this binstub cannot run.
diff --git a/lib/bundler/templates/Executable.bundler b/lib/bundler/templates/Executable.bundler
index 6bb5c51090..e290fe91eb 100644
--- a/lib/bundler/templates/Executable.bundler
+++ b/lib/bundler/templates/Executable.bundler
@@ -41,13 +41,13 @@ m = Module.new do
     gemfile = ENV["BUNDLE_GEMFILE"]
     return gemfile if gemfile && !gemfile.empty?
 
-    File.expand_path("../<%= relative_gemfile_path %>", __FILE__)
+    File.expand_path("<%= relative_gemfile_path %>", __dir__)
   end
 
   def lockfile
     lockfile =
       case File.basename(gemfile)
-      when "gems.rb" then gemfile.sub(/\.rb$/, gemfile)
+      when "gems.rb" then gemfile.sub(/\.rb$/, ".locked")
       else "#{gemfile}.lock"
       end
     File.expand_path(lockfile)
@@ -62,8 +62,9 @@ m = Module.new do
 
   def bundler_requirement
     @bundler_requirement ||=
-      env_var_version || cli_arg_version ||
-        bundler_requirement_for(lockfile_version)
+      env_var_version ||
+      cli_arg_version ||
+      bundler_requirement_for(lockfile_version)
   end
 
   def bundler_requirement_for(version)
@@ -71,13 +72,7 @@ m = Module.new do
 
     bundler_gem_version = Gem::Version.new(version)
 
-    requirement = bundler_gem_version.approximate_recommendation
-
-    return requirement unless Gem.rubygems_version < Gem::Version.new("2.7.0")
-
-    requirement += ".a" if bundler_gem_version.prerelease?
-
-    requirement
+    bundler_gem_version.approximate_recommendation
   end
 
   def load_bundler!
diff --git a/lib/bundler/templates/Executable.standalone b/lib/bundler/templates/Executable.standalone
index 4bf0753f44..3117a27e86 100644
--- a/lib/bundler/templates/Executable.standalone
+++ b/lib/bundler/templates/Executable.standalone
@@ -1,4 +1,6 @@
 #!/usr/bin/env <%= Bundler.settings[:shebang] || RbConfig::CONFIG["ruby_install_name"] %>
+# frozen_string_literal: true
+
 #
 # This file was generated by Bundler.
 #
@@ -6,9 +8,7 @@
 # this file is here to facilitate running it.
 #
 
-require "pathname"
-path = Pathname.new(__FILE__)
-$:.unshift File.expand_path "../<%= standalone_path %>", path.realpath
+$:.unshift File.expand_path "<%= standalone_path %>", __dir__
 
 require "bundler/setup"
-load File.expand_path "../<%= executable_path %>", path.realpath
+load File.expand_path "<%= executable_path %>", __dir__
diff --git a/lib/bundler/templates/gems.rb b/lib/bundler/templates/gems.rb
deleted file mode 100644
index d2403f18b2..0000000000
--- a/lib/bundler/templates/gems.rb
+++ /dev/null
@@ -1,5 +0,0 @@
-# frozen_string_literal: true
-
-source "https://rubygems.org"
-
-# gem "rails"
diff --git a/lib/bundler/templates/newgem/Cargo.toml.tt b/lib/bundler/templates/newgem/Cargo.toml.tt
new file mode 100644
index 0000000000..f5a460c9bb
--- /dev/null
+++ b/lib/bundler/templates/newgem/Cargo.toml.tt
@@ -0,0 +1,7 @@
+# This Cargo.toml is here to let externals tools (IDEs, etc.) know that this is
+# a Rust project. Your extensions dependencies should be added to the Cargo.toml
+# in the ext/ directory.
+
+[workspace]
+members = ["./ext/<%= config[:name] %>"]
+resolver = "2"
diff --git a/lib/bundler/templates/newgem/Gemfile.tt b/lib/bundler/templates/newgem/Gemfile.tt
index de82a63c5f..a0d2ac2826 100644
--- a/lib/bundler/templates/newgem/Gemfile.tt
+++ b/lib/bundler/templates/newgem/Gemfile.tt
@@ -9,6 +9,9 @@ gem "rake", "~> 13.0"
 <%- if config[:ext] -%>
 
 gem "rake-compiler"
+<%- if config[:ext] == 'rust' -%>
+gem "rb_sys", "~> 0.9.63"
+<%- end -%>
 <%- end -%>
 <%- if config[:test] -%>
 
diff --git a/lib/bundler/templates/newgem/README.md.tt b/lib/bundler/templates/newgem/README.md.tt
index a60c7967ec..20eaac8a62 100644
--- a/lib/bundler/templates/newgem/README.md.tt
+++ b/lib/bundler/templates/newgem/README.md.tt
@@ -1,18 +1,20 @@
 # <%= config[:constant_name] %>
 
-Welcome to your new gem! In this directory, you'll find the files you need to be able to package up your Ruby library into a gem. Put your Ruby code in the file `lib/<%= config[:namespaced_path] %>`. To experiment with that code, run `bin/console` for an interactive prompt.
+TODO: Delete this and the text below, and describe your gem
 
-TODO: Delete this and the text above, and describe your gem
+Welcome to your new gem! In this directory, you'll find the files you need to be able to package up your Ruby library into a gem. Put your Ruby code in the file `lib/<%= config[:namespaced_path] %>`. To experiment with that code, run `bin/console` for an interactive prompt.
 
 ## Installation
 
+TODO: Replace `UPDATE_WITH_YOUR_GEM_NAME_PRIOR_TO_RELEASE_TO_RUBYGEMS_ORG` with your gem name right after releasing it to RubyGems.org. Please do not do it earlier due to security reasons. Alternatively, replace this section with instructions to install your gem from git if you don't plan to release to RubyGems.org.
+
 Install the gem and add to the application's Gemfile by executing:
 
-    $ bundle add <%= config[:name] %>
+    $ bundle add UPDATE_WITH_YOUR_GEM_NAME_PRIOR_TO_RELEASE_TO_RUBYGEMS_ORG
 
 If bundler is not being used to manage dependencies, install the gem by executing:
 
-    $ gem install <%= config[:name] %>
+    $ gem install UPDATE_WITH_YOUR_GEM_NAME_PRIOR_TO_RELEASE_TO_RUBYGEMS_ORG
 
 ## Usage
 
diff --git a/lib/bundler/templates/newgem/Rakefile.tt b/lib/bundler/templates/newgem/Rakefile.tt
index b02ada9b6c..b5a5c4e392 100644
--- a/lib/bundler/templates/newgem/Rakefile.tt
+++ b/lib/bundler/templates/newgem/Rakefile.tt
@@ -39,7 +39,17 @@ require "standard/rake"
 
 <% end -%>
 <% if config[:ext] -%>
-<% default_task_names.unshift(:clobber, :compile) -%>
+<% default_task_names.unshift(:compile) -%>
+<% default_task_names.unshift(:clobber) unless config[:ext] == 'rust' -%>
+<% if config[:ext] == 'rust' -%>
+require "rb_sys/extensiontask"
+
+task build: :compile
+
+RbSys::ExtensionTask.new(<%= config[:name].inspect %>) do |ext|
+  ext.lib_dir = "lib/<%= config[:namespaced_path] %>"
+end
+<% else -%>
 require "rake/extensiontask"
 
 task build: :compile
@@ -47,6 +57,7 @@ task build: :compile
 Rake::ExtensionTask.new("<%= config[:underscored_name] %>") do |ext|
   ext.lib_dir = "lib/<%= config[:namespaced_path] %>"
 end
+<% end -%>
 
 <% end -%>
 <% if default_task_names.size == 1 -%>
diff --git a/lib/bundler/templates/newgem/bin/console.tt b/lib/bundler/templates/newgem/bin/console.tt
index 08dfaaef69..c91ee65f93 100644
--- a/lib/bundler/templates/newgem/bin/console.tt
+++ b/lib/bundler/templates/newgem/bin/console.tt
@@ -7,9 +7,5 @@ require "<%= config[:namespaced_path] %>"
 # You can add fixtures and/or initialization code here to make experimenting
 # with your gem easier. You can also use a different console, if you like.
 
-# (If you use this, don't forget to add pry to your Gemfile!)
-# require "pry"
-# Pry.start
-
 require "irb"
 IRB.start(__FILE__)
diff --git a/lib/bundler/templates/newgem/circleci/config.yml.tt b/lib/bundler/templates/newgem/circleci/config.yml.tt
index 79fd0dcc0f..f40f029bf1 100644
--- a/lib/bundler/templates/newgem/circleci/config.yml.tt
+++ b/lib/bundler/templates/newgem/circleci/config.yml.tt
@@ -3,8 +3,20 @@ jobs:
   build:
     docker:
       - image: ruby:<%= RUBY_VERSION %>
+<%- if config[:ext] == 'rust' -%>
+    environment:
+      RB_SYS_FORCE_INSTALL_RUST_TOOLCHAIN: 'true'
+<%- end -%>
     steps:
       - checkout
+<%- if config[:ext] == 'rust' -%>
+      - run:
+          name: Install Rust/Cargo dependencies
+          command: apt-get update && apt-get install -y clang
+      - run:
+          name: Install a RubyGems version that can compile rust extensions
+          command: gem update --system '<%= ::Gem.rubygems_version %>'
+<%- end -%>
       - run:
           name: Run the default task
           command: |
diff --git a/lib/bundler/templates/newgem/ext/newgem/Cargo.toml.tt b/lib/bundler/templates/newgem/ext/newgem/Cargo.toml.tt
new file mode 100644
index 0000000000..c64385486e
--- /dev/null
+++ b/lib/bundler/templates/newgem/ext/newgem/Cargo.toml.tt
@@ -0,0 +1,15 @@
+[package]
+name = <%= config[:name].inspect %>
+version = "0.1.0"
+edition = "2021"
+authors = ["<%= config[:author] %> <<%= config[:email] %>>"]
+<%- if config[:mit] -%>
+license = "MIT"
+<%- end -%>
+publish = false
+
+[lib]
+crate-type = ["cdylib"]
+
+[dependencies]
+magnus = { version = "0.6" }
diff --git a/lib/bundler/templates/newgem/ext/newgem/extconf-c.rb.tt b/lib/bundler/templates/newgem/ext/newgem/extconf-c.rb.tt
new file mode 100644
index 0000000000..0a0c5a3d09
--- /dev/null
+++ b/lib/bundler/templates/newgem/ext/newgem/extconf-c.rb.tt
@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+require "mkmf"
+
+# Makes all symbols private by default to avoid unintended conflict
+# with other gems. To explicitly export symbols you can use RUBY_FUNC_EXPORTED
+# selectively, or entirely remove this flag.
+append_cflags("-fvisibility=hidden")
+
+create_makefile(<%= config[:makefile_path].inspect %>)
diff --git a/lib/bundler/templates/newgem/ext/newgem/extconf-rust.rb.tt b/lib/bundler/templates/newgem/ext/newgem/extconf-rust.rb.tt
new file mode 100644
index 0000000000..e24566a17a
--- /dev/null
+++ b/lib/bundler/templates/newgem/ext/newgem/extconf-rust.rb.tt
@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+require "mkmf"
+require "rb_sys/mkmf"
+
+create_rust_makefile(<%= config[:makefile_path].inspect %>)
diff --git a/lib/bundler/templates/newgem/ext/newgem/extconf.rb.tt b/lib/bundler/templates/newgem/ext/newgem/extconf.rb.tt
deleted file mode 100644
index e918063ddf..0000000000
--- a/lib/bundler/templates/newgem/ext/newgem/extconf.rb.tt
+++ /dev/null
@@ -1,5 +0,0 @@
-# frozen_string_literal: true
-
-require "mkmf"
-
-create_makefile(<%= config[:makefile_path].inspect %>)
diff --git a/lib/bundler/templates/newgem/ext/newgem/newgem.c.tt b/lib/bundler/templates/newgem/ext/newgem/newgem.c.tt
index 8177c4d202..bcd5148569 100644
--- a/lib/bundler/templates/newgem/ext/newgem/newgem.c.tt
+++ b/lib/bundler/templates/newgem/ext/newgem/newgem.c.tt
@@ -2,7 +2,7 @@
 
 VALUE rb_m<%= config[:constant_array].join %>;
 
-void
+RUBY_FUNC_EXPORTED void
 Init_<%= config[:underscored_name] %>(void)
 {
   rb_m<%= config[:constant_array].join %> = rb_define_module(<%= config[:constant_name].inspect %>);
diff --git a/lib/bundler/templates/newgem/ext/newgem/src/lib.rs.tt b/lib/bundler/templates/newgem/ext/newgem/src/lib.rs.tt
new file mode 100644
index 0000000000..ba234529a3
--- /dev/null
+++ b/lib/bundler/templates/newgem/ext/newgem/src/lib.rs.tt
@@ -0,0 +1,12 @@
+use magnus::{function, prelude::*, Error, Ruby};
+
+fn hello(subject: String) -> String {
+    format!("Hello from Rust, {subject}!")
+}
+
+#[magnus::init]
+fn init(ruby: &Ruby) -> Result<(), Error> {
+    let module = ruby.<%= config[:constant_array].map {|c| "define_module(#{c.dump})?"}.join(".") %>;
+    module.define_singleton_method("hello", function!(hello, 1))?;
+    Ok(())
+}
diff --git a/lib/bundler/templates/newgem/github/workflows/main.yml.tt b/lib/bundler/templates/newgem/github/workflows/main.yml.tt
index 1ff4b58b7b..be58dd8156 100644
--- a/lib/bundler/templates/newgem/github/workflows/main.yml.tt
+++ b/lib/bundler/templates/newgem/github/workflows/main.yml.tt
@@ -18,10 +18,20 @@ jobs:
 
     steps:
     - uses: actions/checkout@v3
+<%- if config[:ext] == 'rust' -%>
+    - name: Set up Ruby & Rust
+      uses: oxidize-rb/actions/setup-ruby-and-rust@v1
+      with:
+        ruby-version: ${{ matrix.ruby }}
+        bundler-cache: true
+        cargo-cache: true
+        rubygems: '<%= ::Gem.rubygems_version %>'
+<%- else -%>
     - name: Set up Ruby
       uses: ruby/setup-ruby@v1
       with:
         ruby-version: ${{ matrix.ruby }}
         bundler-cache: true
+<%- end -%>
     - name: Run the default task
       run: bundle exec rake
diff --git a/lib/bundler/templates/newgem/gitignore.tt b/lib/bundler/templates/newgem/gitignore.tt
index b1c9f9986c..9b40ba5a58 100644
--- a/lib/bundler/templates/newgem/gitignore.tt
+++ b/lib/bundler/templates/newgem/gitignore.tt
@@ -12,6 +12,9 @@
 *.o
 *.a
 mkmf.log
+<%- if config[:ext] == 'rust' -%>
+target/
+<%- end -%>
 <%- end -%>
 <%- if config[:test] == "rspec" -%>
 
diff --git a/lib/bundler/templates/newgem/gitlab-ci.yml.tt b/lib/bundler/templates/newgem/gitlab-ci.yml.tt
index 0e71ff26a4..d2e1f33736 100644
--- a/lib/bundler/templates/newgem/gitlab-ci.yml.tt
+++ b/lib/bundler/templates/newgem/gitlab-ci.yml.tt
@@ -1,9 +1,18 @@
-image: ruby:<%= RUBY_VERSION %>
+default:
+  image: ruby:<%= RUBY_VERSION %>
 
-before_script:
-  - gem install bundler -v <%= Bundler::VERSION %>
-  - bundle install
+  before_script:
+<%- if config[:ext] == 'rust' -%>
+    - apt-get update && apt-get install -y clang
+    - gem update --system '<%= ::Gem.rubygems_version %>'
+<%- end -%>
+    - gem install bundler -v <%= Bundler::VERSION %>
+    - bundle install
 
 example_job:
+<%- if config[:ext] == 'rust' -%>
+  variables:
+    RB_SYS_FORCE_INSTALL_RUST_TOOLCHAIN: 'true'
+<%- end -%>
   script:
     - bundle exec rake
diff --git a/lib/bundler/templates/newgem/newgem.gemspec.tt b/lib/bundler/templates/newgem/newgem.gemspec.tt
index 546a28b78a..bb76680379 100644
--- a/lib/bundler/templates/newgem/newgem.gemspec.tt
+++ b/lib/bundler/templates/newgem/newgem.gemspec.tt
@@ -15,6 +15,9 @@ Gem::Specification.new do |spec|
   spec.license = "MIT"
 <%- end -%>
   spec.required_ruby_version = ">= <%= config[:required_ruby_version] %>"
+<%- if config[:ext] == 'rust' -%>
+  spec.required_rubygems_version = ">= <%= config[:rust_builder_required_rubygems_version] %>"
+<%- end -%>
 
   spec.metadata["allowed_push_host"] = "TODO: Set to your gem server 'https://example.com'"
 
@@ -24,17 +27,21 @@ Gem::Specification.new do |spec|
 
   # Specify which files should be added to the gem when it is released.
   # The `git ls-files -z` loads the files in the RubyGem that have been added into git.
-  spec.files = Dir.chdir(File.expand_path(__dir__)) do
+  spec.files = Dir.chdir(__dir__) do
     `git ls-files -z`.split("\x0").reject do |f|
-      (f == __FILE__) || f.match(%r{\A(?:(?:bin|test|spec|features)/|\.(?:git|travis|circleci)|appveyor)})
+      (File.expand_path(f) == __FILE__) ||
+        f.start_with?(*%w[bin/ test/ spec/ features/ .git .circleci appveyor Gemfile])
     end
   end
   spec.bindir = "exe"
   spec.executables = spec.files.grep(%r{\Aexe/}) { |f| File.basename(f) }
   spec.require_paths = ["lib"]
-<%- if config[:ext] -%>
+<%- if config[:ext] == 'c' -%>
   spec.extensions = ["ext/<%= config[:underscored_name] %>/extconf.rb"]
 <%- end -%>
+<%- if config[:ext] == 'rust' -%>
+  spec.extensions = ["ext/<%= config[:underscored_name] %>/Cargo.toml"]
+<%- end -%>
 
   # Uncomment to register a new dependency of your gem
   # spec.add_dependency "example-gem", "~> 1.0"
diff --git a/lib/bundler/templates/newgem/travis.yml.tt b/lib/bundler/templates/newgem/travis.yml.tt
deleted file mode 100644
index eab16addca..0000000000
--- a/lib/bundler/templates/newgem/travis.yml.tt
+++ /dev/null
@@ -1,6 +0,0 @@
----
-language: ruby
-cache: bundler
-rvm:
-  - <%= RUBY_VERSION %>
-before_install: gem install bundler -v <%= Bundler::VERSION %>
diff --git a/lib/bundler/ui/rg_proxy.rb b/lib/bundler/ui/rg_proxy.rb
index ef6def225b..b17ca65f53 100644
--- a/lib/bundler/ui/rg_proxy.rb
+++ b/lib/bundler/ui/rg_proxy.rb
@@ -12,7 +12,7 @@ module Bundler
       end
 
       def say(message)
-        @ui && @ui.debug(message)
+        @ui&.debug(message)
       end
     end
   end
diff --git a/lib/bundler/ui/shell.rb b/lib/bundler/ui/shell.rb
index 384752a340..4139585c47 100644
--- a/lib/bundler/ui/shell.rb
+++ b/lib/bundler/ui/shell.rb
@@ -20,29 +20,52 @@ module Bundler
         @shell.set_color(string, *color)
       end
 
-      def info(msg, newline = nil)
-        tell_me(msg, nil, newline) if level("info")
+      def info(msg = nil, newline = nil)
+        return unless info?
+
+        tell_me(msg || yield, nil, newline)
       end
 
-      def confirm(msg, newline = nil)
-        tell_me(msg, :green, newline) if level("confirm")
+      def confirm(msg = nil, newline = nil)
+        return unless confirm?
+
+        tell_me(msg || yield, :green, newline)
       end
 
-      def warn(msg, newline = nil, color = :yellow)
-        return unless level("warn")
+      def warn(msg = nil, newline = nil, color = :yellow)
+        return unless warn?
         return if @warning_history.include? msg
         @warning_history << msg
 
-        tell_err(msg, color, newline)
+        tell_err(msg || yield, color, newline)
+      end
+
+      def error(msg = nil, newline = nil, color = :red)
+        return unless error?
+
+        tell_err(msg || yield, color, newline)
+      end
+
+      def debug(msg = nil, newline = nil)
+        return unless debug?
+
+        tell_me(msg || yield, nil, newline)
+      end
+
+      def info?
+        level("info")
+      end
+
+      def confirm?
+        level("confirm")
       end
 
-      def error(msg, newline = nil, color = :red)
-        return unless level("error")
-        tell_err(msg, color, newline)
+      def warn?
+        level("warn")
       end
 
-      def debug(msg, newline = nil)
-        tell_me(msg, nil, newline) if debug?
+      def error?
+        level("error")
       end
 
       def debug?
diff --git a/lib/bundler/ui/silent.rb b/lib/bundler/ui/silent.rb
index dca1b2ac86..fa3292bdc9 100644
--- a/lib/bundler/ui/silent.rb
+++ b/lib/bundler/ui/silent.rb
@@ -13,30 +13,46 @@ module Bundler
         string
       end
 
-      def info(message, newline = nil)
+      def info(message = nil, newline = nil)
       end
 
-      def confirm(message, newline = nil)
+      def confirm(message = nil, newline = nil)
       end
 
-      def warn(message, newline = nil)
+      def warn(message = nil, newline = nil)
         @warnings |= [message]
       end
 
-      def error(message, newline = nil)
+      def error(message = nil, newline = nil)
       end
 
-      def debug(message, newline = nil)
+      def debug(message = nil, newline = nil)
+      end
+
+      def confirm?
+        false
+      end
+
+      def error?
+        false
       end
 
       def debug?
         false
       end
 
+      def info?
+        false
+      end
+
       def quiet?
         false
       end
 
+      def warn?
+        false
+      end
+
       def ask(message)
       end
 
diff --git a/lib/bundler/uri_normalizer.rb b/lib/bundler/uri_normalizer.rb
new file mode 100644
index 0000000000..ad08593256
--- /dev/null
+++ b/lib/bundler/uri_normalizer.rb
@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+module Bundler
+  module URINormalizer
+    module_function
+
+    # Normalizes uri to a consistent version, either with or without trailing
+    # slash.
+    #
+    # TODO: Currently gem sources are locked with a trailing slash, while git
+    # sources are locked without a trailing slash. This should be normalized but
+    # the inconsistency is there for now to avoid changing all lockfiles
+    # including GIT sources. We could normalize this on the next major.
+    #
+    def normalize_suffix(uri, trailing_slash: true)
+      if trailing_slash
+        uri.end_with?("/") ? uri : "#{uri}/"
+      else
+        uri.end_with?("/") ? uri.delete_suffix("/") : uri
+      end
+    end
+  end
+end
diff --git a/lib/bundler/vendor/connection_pool/lib/connection_pool.rb b/lib/bundler/vendor/connection_pool/lib/connection_pool.rb
index 984c1c3dcb..455319efe3 100644
--- a/lib/bundler/vendor/connection_pool/lib/connection_pool.rb
+++ b/lib/bundler/vendor/connection_pool/lib/connection_pool.rb
@@ -3,7 +3,9 @@ require_relative "connection_pool/version"
 
 class Bundler::ConnectionPool
   class Error < ::RuntimeError; end
+
   class PoolShuttingDownError < ::Bundler::ConnectionPool::Error; end
+
   class TimeoutError < ::Timeout::Error; end
 end
 
@@ -67,7 +69,7 @@ class Bundler::ConnectionPool
       end
     end
   end
-  alias then with
+  alias_method :then, :with
 
   def checkout(options = {})
     if ::Thread.current[@key]
diff --git a/lib/bundler/vendor/connection_pool/lib/connection_pool/timed_stack.rb b/lib/bundler/vendor/connection_pool/lib/connection_pool/timed_stack.rb
index a7b1cf06a8..35d1d7cc35 100644
--- a/lib/bundler/vendor/connection_pool/lib/connection_pool/timed_stack.rb
+++ b/lib/bundler/vendor/connection_pool/lib/connection_pool/timed_stack.rb
@@ -49,7 +49,7 @@ class Bundler::ConnectionPool::TimedStack
       @resource.broadcast
     end
   end
-  alias << push
+  alias_method :<<, :push
 
   ##
   # Retrieves a connection from the stack.  If a connection is available it is
@@ -74,7 +74,7 @@ class Bundler::ConnectionPool::TimedStack
         return connection if connection
 
         to_wait = deadline - current_time
-        raise Bundler::ConnectionPool::TimeoutError, "Waited #{timeout} sec" if to_wait <= 0
+        raise Bundler::ConnectionPool::TimeoutError, "Waited #{timeout} sec, #{length}/#{@max} available" if to_wait <= 0
         @resource.wait(@mutex, to_wait)
       end
     end
@@ -87,7 +87,7 @@ class Bundler::ConnectionPool::TimedStack
   # +:reload+ is +true+.
 
   def shutdown(reload: false, &block)
-    raise ArgumentError, "shutdown must receive a block" unless block_given?
+    raise ArgumentError, "shutdown must receive a block" unless block
 
     @mutex.synchronize do
       @shutdown_block = block
diff --git a/lib/bundler/vendor/connection_pool/lib/connection_pool/wrapper.rb b/lib/bundler/vendor/connection_pool/lib/connection_pool/wrapper.rb
index 880170c06b..dd796d1021 100644
--- a/lib/bundler/vendor/connection_pool/lib/connection_pool/wrapper.rb
+++ b/lib/bundler/vendor/connection_pool/lib/connection_pool/wrapper.rb
@@ -30,7 +30,6 @@ class Bundler::ConnectionPool
       METHODS.include?(id) || with { |c| c.respond_to?(id, *args) }
     end
 
-    # rubocop:disable Style/MethodMissingSuper
     # rubocop:disable Style/MissingRespondToMissing
     if ::RUBY_VERSION >= "3.0.0"
       def method_missing(name, *args, **kwargs, &block)
diff --git a/lib/bundler/vendor/fileutils/lib/fileutils.rb b/lib/bundler/vendor/fileutils/lib/fileutils.rb
index 8f8faf30c8..211311c069 100644
--- a/lib/bundler/vendor/fileutils/lib/fileutils.rb
+++ b/lib/bundler/vendor/fileutils/lib/fileutils.rb
@@ -3,106 +3,184 @@
 begin
   require 'rbconfig'
 rescue LoadError
-  # for make mjit-headers
+  # for make rjit-headers
 end
 
+# Namespace for file utility methods for copying, moving, removing, etc.
 #
-# = fileutils.rb
+# == What's Here
 #
-# Copyright (c) 2000-2007 Minero Aoki
+# First, what’s elsewhere. \Module \Bundler::FileUtils:
 #
-# This program is free software.
-# You can distribute/modify this program under the same terms of ruby.
+# - Inherits from {class Object}[rdoc-ref:Object].
+# - Supplements {class File}[rdoc-ref:File]
+#   (but is not included or extended there).
 #
-# == module Bundler::FileUtils
+# Here, module \Bundler::FileUtils provides methods that are useful for:
 #
-# Namespace for several file utility methods for copying, moving, removing, etc.
+# - {Creating}[rdoc-ref:FileUtils@Creating].
+# - {Deleting}[rdoc-ref:FileUtils@Deleting].
+# - {Querying}[rdoc-ref:FileUtils@Querying].
+# - {Setting}[rdoc-ref:FileUtils@Setting].
+# - {Comparing}[rdoc-ref:FileUtils@Comparing].
+# - {Copying}[rdoc-ref:FileUtils@Copying].
+# - {Moving}[rdoc-ref:FileUtils@Moving].
+# - {Options}[rdoc-ref:FileUtils@Options].
 #
-# === Module Functions
+# === Creating
 #
-#   require 'bundler/vendor/fileutils/lib/fileutils'
+# - ::mkdir: Creates directories.
+# - ::mkdir_p, ::makedirs, ::mkpath: Creates directories,
+#   also creating ancestor directories as needed.
+# - ::link_entry: Creates a hard link.
+# - ::ln, ::link: Creates hard links.
+# - ::ln_s, ::symlink: Creates symbolic links.
+# - ::ln_sf: Creates symbolic links, overwriting if necessary.
+# - ::ln_sr: Creates symbolic links relative to targets
 #
-#   Bundler::FileUtils.cd(dir, **options)
-#   Bundler::FileUtils.cd(dir, **options) {|dir| block }
-#   Bundler::FileUtils.pwd()
-#   Bundler::FileUtils.mkdir(dir, **options)
-#   Bundler::FileUtils.mkdir(list, **options)
-#   Bundler::FileUtils.mkdir_p(dir, **options)
-#   Bundler::FileUtils.mkdir_p(list, **options)
-#   Bundler::FileUtils.rmdir(dir, **options)
-#   Bundler::FileUtils.rmdir(list, **options)
-#   Bundler::FileUtils.ln(target, link, **options)
-#   Bundler::FileUtils.ln(targets, dir, **options)
-#   Bundler::FileUtils.ln_s(target, link, **options)
-#   Bundler::FileUtils.ln_s(targets, dir, **options)
-#   Bundler::FileUtils.ln_sf(target, link, **options)
-#   Bundler::FileUtils.cp(src, dest, **options)
-#   Bundler::FileUtils.cp(list, dir, **options)
-#   Bundler::FileUtils.cp_r(src, dest, **options)
-#   Bundler::FileUtils.cp_r(list, dir, **options)
-#   Bundler::FileUtils.mv(src, dest, **options)
-#   Bundler::FileUtils.mv(list, dir, **options)
-#   Bundler::FileUtils.rm(list, **options)
-#   Bundler::FileUtils.rm_r(list, **options)
-#   Bundler::FileUtils.rm_rf(list, **options)
-#   Bundler::FileUtils.install(src, dest, **options)
-#   Bundler::FileUtils.chmod(mode, list, **options)
-#   Bundler::FileUtils.chmod_R(mode, list, **options)
-#   Bundler::FileUtils.chown(user, group, list, **options)
-#   Bundler::FileUtils.chown_R(user, group, list, **options)
-#   Bundler::FileUtils.touch(list, **options)
+# === Deleting
 #
-# Possible <tt>options</tt> are:
+# - ::remove_dir: Removes a directory and its descendants.
+# - ::remove_entry: Removes an entry, including its descendants if it is a directory.
+# - ::remove_entry_secure: Like ::remove_entry, but removes securely.
+# - ::remove_file: Removes a file entry.
+# - ::rm, ::remove: Removes entries.
+# - ::rm_f, ::safe_unlink: Like ::rm, but removes forcibly.
+# - ::rm_r: Removes entries and their descendants.
+# - ::rm_rf, ::rmtree: Like ::rm_r, but removes forcibly.
+# - ::rmdir: Removes directories.
 #
-# <tt>:force</tt> :: forced operation (rewrite files if exist, remove
-#                    directories if not empty, etc.);
-# <tt>:verbose</tt> :: print command to be run, in bash syntax, before
-#                      performing it;
-# <tt>:preserve</tt> :: preserve object's group, user and modification
-#                       time on copying;
-# <tt>:noop</tt> :: no changes are made (usable in combination with
-#                   <tt>:verbose</tt> which will print the command to run)
+# === Querying
 #
-# Each method documents the options that it honours. See also ::commands,
-# ::options and ::options_of methods to introspect which command have which
-# options.
+# - ::pwd, ::getwd: Returns the path to the working directory.
+# - ::uptodate?: Returns whether a given entry is newer than given other entries.
 #
-# All methods that have the concept of a "source" file or directory can take
-# either one file or a list of files in that argument.  See the method
-# documentation for examples.
+# === Setting
 #
-# There are some `low level' methods, which do not accept keyword arguments:
+# - ::cd, ::chdir: Sets the working directory.
+# - ::chmod: Sets permissions for an entry.
+# - ::chmod_R: Sets permissions for an entry and its descendants.
+# - ::chown: Sets the owner and group for entries.
+# - ::chown_R: Sets the owner and group for entries and their descendants.
+# - ::touch: Sets modification and access times for entries,
+#   creating if necessary.
 #
-#   Bundler::FileUtils.copy_entry(src, dest, preserve = false, dereference_root = false, remove_destination = false)
-#   Bundler::FileUtils.copy_file(src, dest, preserve = false, dereference = true)
-#   Bundler::FileUtils.copy_stream(srcstream, deststream)
-#   Bundler::FileUtils.remove_entry(path, force = false)
-#   Bundler::FileUtils.remove_entry_secure(path, force = false)
-#   Bundler::FileUtils.remove_file(path, force = false)
-#   Bundler::FileUtils.compare_file(path_a, path_b)
-#   Bundler::FileUtils.compare_stream(stream_a, stream_b)
-#   Bundler::FileUtils.uptodate?(file, cmp_list)
+# === Comparing
 #
-# == module Bundler::FileUtils::Verbose
+# - ::compare_file, ::cmp, ::identical?: Returns whether two entries are identical.
+# - ::compare_stream: Returns whether two streams are identical.
 #
-# This module has all methods of Bundler::FileUtils module, but it outputs messages
-# before acting.  This equates to passing the <tt>:verbose</tt> flag to methods
-# in Bundler::FileUtils.
+# === Copying
 #
-# == module Bundler::FileUtils::NoWrite
+# - ::copy_entry: Recursively copies an entry.
+# - ::copy_file: Copies an entry.
+# - ::copy_stream: Copies a stream.
+# - ::cp, ::copy: Copies files.
+# - ::cp_lr: Recursively creates hard links.
+# - ::cp_r: Recursively copies files, retaining mode, owner, and group.
+# - ::install: Recursively copies files, optionally setting mode,
+#   owner, and group.
 #
-# This module has all methods of Bundler::FileUtils module, but never changes
-# files/directories.  This equates to passing the <tt>:noop</tt> flag to methods
-# in Bundler::FileUtils.
+# === Moving
 #
-# == module Bundler::FileUtils::DryRun
+# - ::mv, ::move: Moves entries.
 #
-# This module has all methods of Bundler::FileUtils module, but never changes
-# files/directories.  This equates to passing the <tt>:noop</tt> and
-# <tt>:verbose</tt> flags to methods in Bundler::FileUtils.
+# === Options
+#
+# - ::collect_method: Returns the names of methods that accept a given option.
+# - ::commands: Returns the names of methods that accept options.
+# - ::have_option?: Returns whether a given method accepts a given option.
+# - ::options: Returns all option names.
+# - ::options_of: Returns the names of the options for a given method.
+#
+# == Path Arguments
+#
+# Some methods in \Bundler::FileUtils accept _path_ arguments,
+# which are interpreted as paths to filesystem entries:
+#
+# - If the argument is a string, that value is the path.
+# - If the argument has method +:to_path+, it is converted via that method.
+# - If the argument has method +:to_str+, it is converted via that method.
+#
+# == About the Examples
+#
+# Some examples here involve trees of file entries.
+# For these, we sometimes display trees using the
+# {tree command-line utility}[https://en.wikipedia.org/wiki/Tree_(command)],
+# which is a recursive directory-listing utility that produces
+# a depth-indented listing of files and directories.
+#
+# We use a helper method to launch the command and control the format:
+#
+#   def tree(dirpath = '.')
+#     command = "tree --noreport --charset=ascii #{dirpath}"
+#     system(command)
+#   end
+#
+# To illustrate:
+#
+#   tree('src0')
+#   # => src0
+#   #    |-- sub0
+#   #    |   |-- src0.txt
+#   #    |   `-- src1.txt
+#   #    `-- sub1
+#   #        |-- src2.txt
+#   #        `-- src3.txt
+#
+# == Avoiding the TOCTTOU Vulnerability
+#
+# For certain methods that recursively remove entries,
+# there is a potential vulnerability called the
+# {Time-of-check to time-of-use}[https://en.wikipedia.org/wiki/Time-of-check_to_time-of-use],
+# or TOCTTOU, vulnerability that can exist when:
+#
+# - An ancestor directory of the entry at the target path is world writable;
+#   such directories include <tt>/tmp</tt>.
+# - The directory tree at the target path includes:
+#
+#   - A world-writable descendant directory.
+#   - A symbolic link.
+#
+# To avoid that vulnerability, you can use this method to remove entries:
+#
+# - Bundler::FileUtils.remove_entry_secure: removes recursively
+#   if the target path points to a directory.
+#
+# Also available are these methods,
+# each of which calls \Bundler::FileUtils.remove_entry_secure:
+#
+# - Bundler::FileUtils.rm_r with keyword argument <tt>secure: true</tt>.
+# - Bundler::FileUtils.rm_rf with keyword argument <tt>secure: true</tt>.
+#
+# Finally, this method for moving entries calls \Bundler::FileUtils.remove_entry_secure
+# if the source and destination are on different file systems
+# (which means that the "move" is really a copy and remove):
+#
+# - Bundler::FileUtils.mv with keyword argument <tt>secure: true</tt>.
+#
+# \Method \Bundler::FileUtils.remove_entry_secure removes securely
+# by applying a special pre-process:
+#
+# - If the target path points to a directory, this method uses methods
+#   {File#chown}[rdoc-ref:File#chown]
+#   and {File#chmod}[rdoc-ref:File#chmod]
+#   in removing directories.
+# - The owner of the target directory should be either the current process
+#   or the super user (root).
+#
+# WARNING: You must ensure that *ALL* parent directories cannot be
+# moved by other untrusted users.  For example, parent directories
+# should not be owned by untrusted users, and should not be world
+# writable except when the sticky bit is set.
+#
+# For details of this security vulnerability, see Perl cases:
+#
+# - {CVE-2005-0448}[https://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2005-0448].
+# - {CVE-2004-0452}[https://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2004-0452].
 #
 module Bundler::FileUtils
-  VERSION = "1.4.1"
+  VERSION = "1.7.0"
 
   def self.private_module_function(name)   #:nodoc:
     module_function name
@@ -110,7 +188,13 @@ module Bundler::FileUtils
   end
 
   #
-  # Returns the name of the current directory.
+  # Returns a string containing the path to the current directory:
+  #
+  #   Bundler::FileUtils.pwd # => "/rdoc/fileutils"
+  #
+  # Bundler::FileUtils.getwd is an alias for Bundler::FileUtils.pwd.
+  #
+  # Related: Bundler::FileUtils.cd.
   #
   def pwd
     Dir.pwd
@@ -120,19 +204,40 @@ module Bundler::FileUtils
   alias getwd pwd
   module_function :getwd
 
+  # Changes the working directory to the given +dir+, which
+  # should be {interpretable as a path}[rdoc-ref:FileUtils@Path+Arguments]:
+  #
+  # With no block given,
+  # changes the current directory to the directory at +dir+; returns zero:
+  #
+  #   Bundler::FileUtils.pwd # => "/rdoc/fileutils"
+  #   Bundler::FileUtils.cd('..')
+  #   Bundler::FileUtils.pwd # => "/rdoc"
+  #   Bundler::FileUtils.cd('fileutils')
+  #
+  # With a block given, changes the current directory to the directory
+  # at +dir+, calls the block with argument +dir+,
+  # and restores the original current directory; returns the block's value:
   #
-  # Changes the current directory to the directory +dir+.
+  #   Bundler::FileUtils.pwd                                     # => "/rdoc/fileutils"
+  #   Bundler::FileUtils.cd('..') { |arg| [arg, Bundler::FileUtils.pwd] } # => ["..", "/rdoc"]
+  #   Bundler::FileUtils.pwd                                     # => "/rdoc/fileutils"
   #
-  # If this method is called with block, resumes to the previous
-  # working directory after the block execution has finished.
+  # Keyword arguments:
   #
-  #   Bundler::FileUtils.cd('/')  # change directory
+  # - <tt>verbose: true</tt> - prints an equivalent command:
   #
-  #   Bundler::FileUtils.cd('/', verbose: true)   # change directory and report it
+  #     Bundler::FileUtils.cd('..')
+  #     Bundler::FileUtils.cd('fileutils')
   #
-  #   Bundler::FileUtils.cd('/') do  # change directory
-  #     # ...               # do something
-  #   end                   # return to original directory
+  #   Output:
+  #
+  #     cd ..
+  #     cd fileutils
+  #
+  # Bundler::FileUtils.chdir is an alias for Bundler::FileUtils.cd.
+  #
+  # Related: Bundler::FileUtils.pwd.
   #
   def cd(dir, verbose: nil, &block) # :yield: dir
     fu_output_message "cd #{dir}" if verbose
@@ -146,11 +251,19 @@ module Bundler::FileUtils
   module_function :chdir
 
   #
-  # Returns true if +new+ is newer than all +old_list+.
-  # Non-existent files are older than any file.
+  # Returns +true+ if the file at path +new+
+  # is newer than all the files at paths in array +old_list+;
+  # +false+ otherwise.
+  #
+  # Argument +new+ and the elements of +old_list+
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments]:
   #
-  #   Bundler::FileUtils.uptodate?('hello.o', %w(hello.c hello.h)) or \
-  #       system 'make hello.o'
+  #   Bundler::FileUtils.uptodate?('Rakefile', ['Gemfile', 'README.md']) # => true
+  #   Bundler::FileUtils.uptodate?('Gemfile', ['Rakefile', 'README.md']) # => false
+  #
+  # A non-existent file is considered to be infinitely old.
+  #
+  # Related: Bundler::FileUtils.touch.
   #
   def uptodate?(new, old_list)
     return false unless File.exist?(new)
@@ -170,12 +283,39 @@ module Bundler::FileUtils
   private_module_function :remove_trailing_slash
 
   #
-  # Creates one or more directories.
+  # Creates directories at the paths in the given +list+
+  # (a single path or an array of paths);
+  # returns +list+ if it is an array, <tt>[list]</tt> otherwise.
+  #
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # With no keyword arguments, creates a directory at each +path+ in +list+
+  # by calling: <tt>Dir.mkdir(path, mode)</tt>;
+  # see {Dir.mkdir}[rdoc-ref:Dir.mkdir]:
+  #
+  #   Bundler::FileUtils.mkdir(%w[tmp0 tmp1]) # => ["tmp0", "tmp1"]
+  #   Bundler::FileUtils.mkdir('tmp4')        # => ["tmp4"]
+  #
+  # Keyword arguments:
+  #
+  # - <tt>mode: <i>mode</i></tt> - also calls <tt>File.chmod(mode, path)</tt>;
+  #   see {File.chmod}[rdoc-ref:File.chmod].
+  # - <tt>noop: true</tt> - does not create directories.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     Bundler::FileUtils.mkdir(%w[tmp0 tmp1], verbose: true)
+  #     Bundler::FileUtils.mkdir(%w[tmp2 tmp3], mode: 0700, verbose: true)
+  #
+  #   Output:
   #
-  #   Bundler::FileUtils.mkdir 'test'
-  #   Bundler::FileUtils.mkdir %w(tmp data)
-  #   Bundler::FileUtils.mkdir 'notexist', noop: true  # Does not really create.
-  #   Bundler::FileUtils.mkdir 'tmp', mode: 0700
+  #     mkdir tmp0 tmp1
+  #     mkdir -m 700 tmp2 tmp3
+  #
+  # Raises an exception if any path points to an existing
+  # file or directory, or if for any reason a directory cannot be created.
+  #
+  # Related: Bundler::FileUtils.mkdir_p.
   #
   def mkdir(list, mode: nil, noop: nil, verbose: nil)
     list = fu_list(list)
@@ -189,40 +329,56 @@ module Bundler::FileUtils
   module_function :mkdir
 
   #
-  # Creates a directory and all its parent directories.
-  # For example,
+  # Creates directories at the paths in the given +list+
+  # (a single path or an array of paths),
+  # also creating ancestor directories as needed;
+  # returns +list+ if it is an array, <tt>[list]</tt> otherwise.
+  #
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # With no keyword arguments, creates a directory at each +path+ in +list+,
+  # along with any needed ancestor directories,
+  # by calling: <tt>Dir.mkdir(path, mode)</tt>;
+  # see {Dir.mkdir}[rdoc-ref:Dir.mkdir]:
+  #
+  #   Bundler::FileUtils.mkdir_p(%w[tmp0/tmp1 tmp2/tmp3]) # => ["tmp0/tmp1", "tmp2/tmp3"]
+  #   Bundler::FileUtils.mkdir_p('tmp4/tmp5')             # => ["tmp4/tmp5"]
+  #
+  # Keyword arguments:
+  #
+  # - <tt>mode: <i>mode</i></tt> - also calls <tt>File.chmod(mode, path)</tt>;
+  #   see {File.chmod}[rdoc-ref:File.chmod].
+  # - <tt>noop: true</tt> - does not create directories.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     Bundler::FileUtils.mkdir_p(%w[tmp0 tmp1], verbose: true)
+  #     Bundler::FileUtils.mkdir_p(%w[tmp2 tmp3], mode: 0700, verbose: true)
   #
-  #   Bundler::FileUtils.mkdir_p '/usr/local/lib/ruby'
+  #   Output:
   #
-  # causes to make following directories, if they do not exist.
+  #     mkdir -p tmp0 tmp1
+  #     mkdir -p -m 700 tmp2 tmp3
   #
-  # * /usr
-  # * /usr/local
-  # * /usr/local/lib
-  # * /usr/local/lib/ruby
+  # Raises an exception if for any reason a directory cannot be created.
   #
-  # You can pass several directories at a time in a list.
+  # Bundler::FileUtils.mkpath and Bundler::FileUtils.makedirs are aliases for Bundler::FileUtils.mkdir_p.
+  #
+  # Related: Bundler::FileUtils.mkdir.
   #
   def mkdir_p(list, mode: nil, noop: nil, verbose: nil)
     list = fu_list(list)
     fu_output_message "mkdir -p #{mode ? ('-m %03o ' % mode) : ''}#{list.join ' '}" if verbose
     return *list if noop
 
-    list.map {|path| remove_trailing_slash(path)}.each do |path|
-      # optimize for the most common case
-      begin
-        fu_mkdir path, mode
-        next
-      rescue SystemCallError
-        next if File.directory?(path)
-      end
+    list.each do |item|
+      path = remove_trailing_slash(item)
 
       stack = []
-      until path == stack.last   # dirname("/")=="/", dirname("C:/")=="C:/"
+      until File.directory?(path) || File.dirname(path) == path
         stack.push path
         path = File.dirname(path)
       end
-      stack.pop                 # root directory should exist
       stack.reverse_each do |dir|
         begin
           fu_mkdir dir, mode
@@ -253,12 +409,39 @@ module Bundler::FileUtils
   private_module_function :fu_mkdir
 
   #
-  # Removes one or more directories.
+  # Removes directories at the paths in the given +list+
+  # (a single path or an array of paths);
+  # returns +list+, if it is an array, <tt>[list]</tt> otherwise.
+  #
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # With no keyword arguments, removes the directory at each +path+ in +list+,
+  # by calling: <tt>Dir.rmdir(path)</tt>;
+  # see {Dir.rmdir}[rdoc-ref:Dir.rmdir]:
+  #
+  #   Bundler::FileUtils.rmdir(%w[tmp0/tmp1 tmp2/tmp3]) # => ["tmp0/tmp1", "tmp2/tmp3"]
+  #   Bundler::FileUtils.rmdir('tmp4/tmp5')             # => ["tmp4/tmp5"]
+  #
+  # Keyword arguments:
+  #
+  # - <tt>parents: true</tt> - removes successive ancestor directories
+  #   if empty.
+  # - <tt>noop: true</tt> - does not remove directories.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
   #
-  #   Bundler::FileUtils.rmdir 'somedir'
-  #   Bundler::FileUtils.rmdir %w(somedir anydir otherdir)
-  #   # Does not really remove directory; outputs message.
-  #   Bundler::FileUtils.rmdir 'somedir', verbose: true, noop: true
+  #     Bundler::FileUtils.rmdir(%w[tmp0/tmp1 tmp2/tmp3], parents: true, verbose: true)
+  #     Bundler::FileUtils.rmdir('tmp4/tmp5', parents: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     rmdir -p tmp0/tmp1 tmp2/tmp3
+  #     rmdir -p tmp4/tmp5
+  #
+  # Raises an exception if a directory does not exist
+  # or if for any reason a directory cannot be removed.
+  #
+  # Related: {methods for deleting}[rdoc-ref:FileUtils@Deleting].
   #
   def rmdir(list, parents: nil, noop: nil, verbose: nil)
     list = fu_list(list)
@@ -279,26 +462,62 @@ module Bundler::FileUtils
   end
   module_function :rmdir
 
+  # Creates {hard links}[https://en.wikipedia.org/wiki/Hard_link].
+  #
+  # Arguments +src+ (a single path or an array of paths)
+  # and +dest+ (a single path)
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # When +src+ is the path to an existing file
+  # and +dest+ is the path to a non-existent file,
+  # creates a hard link at +dest+ pointing to +src+; returns zero:
+  #
+  #   Dir.children('tmp0/')                    # => ["t.txt"]
+  #   Dir.children('tmp1/')                    # => []
+  #   Bundler::FileUtils.ln('tmp0/t.txt', 'tmp1/t.lnk') # => 0
+  #   Dir.children('tmp1/')                    # => ["t.lnk"]
+  #
+  # When +src+ is the path to an existing file
+  # and +dest+ is the path to an existing directory,
+  # creates a hard link at <tt>dest/src</tt> pointing to +src+; returns zero:
   #
-  # :call-seq:
-  #   Bundler::FileUtils.ln(target, link, force: nil, noop: nil, verbose: nil)
-  #   Bundler::FileUtils.ln(target,  dir, force: nil, noop: nil, verbose: nil)
-  #   Bundler::FileUtils.ln(targets, dir, force: nil, noop: nil, verbose: nil)
+  #   Dir.children('tmp2')               # => ["t.dat"]
+  #   Dir.children('tmp3')               # => []
+  #   Bundler::FileUtils.ln('tmp2/t.dat', 'tmp3') # => 0
+  #   Dir.children('tmp3')               # => ["t.dat"]
   #
-  # In the first form, creates a hard link +link+ which points to +target+.
-  # If +link+ already exists, raises Errno::EEXIST.
-  # But if the +force+ option is set, overwrites +link+.
+  # When +src+ is an array of paths to existing files
+  # and +dest+ is the path to an existing directory,
+  # then for each path +target+ in +src+,
+  # creates a hard link at <tt>dest/target</tt> pointing to +target+;
+  # returns +src+:
   #
-  #   Bundler::FileUtils.ln 'gcc', 'cc', verbose: true
-  #   Bundler::FileUtils.ln '/usr/bin/emacs21', '/usr/bin/emacs'
+  #   Dir.children('tmp4/')                               # => []
+  #   Bundler::FileUtils.ln(['tmp0/t.txt', 'tmp2/t.dat'], 'tmp4/') # => ["tmp0/t.txt", "tmp2/t.dat"]
+  #   Dir.children('tmp4/')                               # => ["t.dat", "t.txt"]
   #
-  # In the second form, creates a link +dir/target+ pointing to +target+.
-  # In the third form, creates several hard links in the directory +dir+,
-  # pointing to each item in +targets+.
-  # If +dir+ is not a directory, raises Errno::ENOTDIR.
+  # Keyword arguments:
   #
-  #   Bundler::FileUtils.cd '/sbin'
-  #   Bundler::FileUtils.ln %w(cp mv mkdir), '/bin'   # Now /sbin/cp and /bin/cp are linked.
+  # - <tt>force: true</tt> - overwrites +dest+ if it exists.
+  # - <tt>noop: true</tt> - does not create links.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     Bundler::FileUtils.ln('tmp0/t.txt', 'tmp1/t.lnk', verbose: true)
+  #     Bundler::FileUtils.ln('tmp2/t.dat', 'tmp3', verbose: true)
+  #     Bundler::FileUtils.ln(['tmp0/t.txt', 'tmp2/t.dat'], 'tmp4/', verbose: true)
+  #
+  #   Output:
+  #
+  #     ln tmp0/t.txt tmp1/t.lnk
+  #     ln tmp2/t.dat tmp3
+  #     ln tmp0/t.txt tmp2/t.dat tmp4/
+  #
+  # Raises an exception if +dest+ is the path to an existing file
+  # and keyword argument +force+ is not +true+.
+  #
+  # Bundler::FileUtils#link is an alias for Bundler::FileUtils#ln.
+  #
+  # Related: Bundler::FileUtils.link_entry (has different options).
   #
   def ln(src, dest, force: nil, noop: nil, verbose: nil)
     fu_output_message "ln#{force ? ' -f' : ''} #{[src,dest].flatten.join ' '}" if verbose
@@ -313,28 +532,103 @@ module Bundler::FileUtils
   alias link ln
   module_function :link
 
-  #
-  # Hard link +src+ to +dest+. If +src+ is a directory, this method links
-  # all its contents recursively. If +dest+ is a directory, links
-  # +src+ to +dest/src+.
-  #
-  # +src+ can be a list of files.
-  #
-  # If +dereference_root+ is true, this method dereference tree root.
-  #
-  # If +remove_destination+ is true, this method removes each destination file before copy.
-  #
-  #   Bundler::FileUtils.rm_r site_ruby + '/mylib', force: true
-  #   Bundler::FileUtils.cp_lr 'lib/', site_ruby + '/mylib'
-  #
-  #   # Examples of linking several files to target directory.
-  #   Bundler::FileUtils.cp_lr %w(mail.rb field.rb debug/), site_ruby + '/tmail'
-  #   Bundler::FileUtils.cp_lr Dir.glob('*.rb'), '/home/aamine/lib/ruby', noop: true, verbose: true
-  #
-  #   # If you want to link all contents of a directory instead of the
-  #   # directory itself, c.f. src/x -> dest/x, src/y -> dest/y,
-  #   # use the following code.
-  #   Bundler::FileUtils.cp_lr 'src/.', 'dest'  # cp_lr('src', 'dest') makes dest/src, but this doesn't.
+  # Creates {hard links}[https://en.wikipedia.org/wiki/Hard_link].
+  #
+  # Arguments +src+ (a single path or an array of paths)
+  # and +dest+ (a single path)
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # If +src+ is the path to a directory and +dest+ does not exist,
+  # creates links +dest+ and descendents pointing to +src+ and its descendents:
+  #
+  #   tree('src0')
+  #   # => src0
+  #   #    |-- sub0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- sub1
+  #   #        |-- src2.txt
+  #   #        `-- src3.txt
+  #   File.exist?('dest0') # => false
+  #   Bundler::FileUtils.cp_lr('src0', 'dest0')
+  #   tree('dest0')
+  #   # => dest0
+  #   #    |-- sub0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- sub1
+  #   #        |-- src2.txt
+  #   #        `-- src3.txt
+  #
+  # If +src+ and +dest+ are both paths to directories,
+  # creates links <tt>dest/src</tt> and descendents
+  # pointing to +src+ and its descendents:
+  #
+  #   tree('src1')
+  #   # => src1
+  #   #    |-- sub0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- sub1
+  #   #        |-- src2.txt
+  #   #        `-- src3.txt
+  #   Bundler::FileUtils.mkdir('dest1')
+  #   Bundler::FileUtils.cp_lr('src1', 'dest1')
+  #   tree('dest1')
+  #   # => dest1
+  #   #    `-- src1
+  #   #        |-- sub0
+  #   #        |   |-- src0.txt
+  #   #        |   `-- src1.txt
+  #   #        `-- sub1
+  #   #            |-- src2.txt
+  #   #            `-- src3.txt
+  #
+  # If +src+ is an array of paths to entries and +dest+ is the path to a directory,
+  # for each path +filepath+ in +src+, creates a link at <tt>dest/filepath</tt>
+  # pointing to that path:
+  #
+  #   tree('src2')
+  #   # => src2
+  #   #    |-- sub0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- sub1
+  #   #        |-- src2.txt
+  #   #        `-- src3.txt
+  #   Bundler::FileUtils.mkdir('dest2')
+  #   Bundler::FileUtils.cp_lr(['src2/sub0', 'src2/sub1'], 'dest2')
+  #   tree('dest2')
+  #   # => dest2
+  #   #    |-- sub0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- sub1
+  #   #        |-- src2.txt
+  #   #        `-- src3.txt
+  #
+  # Keyword arguments:
+  #
+  # - <tt>dereference_root: false</tt> - if +src+ is a symbolic link,
+  #   does not dereference it.
+  # - <tt>noop: true</tt> - does not create links.
+  # - <tt>remove_destination: true</tt> - removes +dest+ before creating links.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     Bundler::FileUtils.cp_lr('src0', 'dest0', noop: true, verbose: true)
+  #     Bundler::FileUtils.cp_lr('src1', 'dest1', noop: true, verbose: true)
+  #     Bundler::FileUtils.cp_lr(['src2/sub0', 'src2/sub1'], 'dest2', noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     cp -lr src0 dest0
+  #     cp -lr src1 dest1
+  #     cp -lr src2/sub0 src2/sub1 dest2
+  #
+  # Raises an exception if +dest+ is the path to an existing file or directory
+  # and keyword argument <tt>remove_destination: true</tt> is not given.
+  #
+  # Related: {methods for copying}[rdoc-ref:FileUtils@Copying].
   #
   def cp_lr(src, dest, noop: nil, verbose: nil,
             dereference_root: true, remove_destination: false)
@@ -346,27 +640,81 @@ module Bundler::FileUtils
   end
   module_function :cp_lr
 
+  # Creates {symbolic links}[https://en.wikipedia.org/wiki/Symbolic_link].
+  #
+  # Arguments +src+ (a single path or an array of paths)
+  # and +dest+ (a single path)
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # If +src+ is the path to an existing file:
+  #
+  # - When +dest+ is the path to a non-existent file,
+  #   creates a symbolic link at +dest+ pointing to +src+:
+  #
+  #     Bundler::FileUtils.touch('src0.txt')
+  #     File.exist?('dest0.txt')   # => false
+  #     Bundler::FileUtils.ln_s('src0.txt', 'dest0.txt')
+  #     File.symlink?('dest0.txt') # => true
   #
-  # :call-seq:
-  #   Bundler::FileUtils.ln_s(target, link, force: nil, noop: nil, verbose: nil)
-  #   Bundler::FileUtils.ln_s(target,  dir, force: nil, noop: nil, verbose: nil)
-  #   Bundler::FileUtils.ln_s(targets, dir, force: nil, noop: nil, verbose: nil)
+  # - When +dest+ is the path to an existing file,
+  #   creates a symbolic link at +dest+ pointing to +src+
+  #   if and only if keyword argument <tt>force: true</tt> is given
+  #   (raises an exception otherwise):
   #
-  # In the first form, creates a symbolic link +link+ which points to +target+.
-  # If +link+ already exists, raises Errno::EEXIST.
-  # But if the <tt>force</tt> option is set, overwrites +link+.
+  #     Bundler::FileUtils.touch('src1.txt')
+  #     Bundler::FileUtils.touch('dest1.txt')
+  #     Bundler::FileUtils.ln_s('src1.txt', 'dest1.txt', force: true)
+  #     FileTest.symlink?('dest1.txt') # => true
   #
-  #   Bundler::FileUtils.ln_s '/usr/bin/ruby', '/usr/local/bin/ruby'
-  #   Bundler::FileUtils.ln_s 'verylongsourcefilename.c', 'c', force: true
+  #     Bundler::FileUtils.ln_s('src1.txt', 'dest1.txt') # Raises Errno::EEXIST.
   #
-  # In the second form, creates a link +dir/target+ pointing to +target+.
-  # In the third form, creates several symbolic links in the directory +dir+,
-  # pointing to each item in +targets+.
-  # If +dir+ is not a directory, raises Errno::ENOTDIR.
+  # If +dest+ is the path to a directory,
+  # creates a symbolic link at <tt>dest/src</tt> pointing to +src+:
   #
-  #   Bundler::FileUtils.ln_s Dir.glob('/bin/*.rb'), '/home/foo/bin'
+  #   Bundler::FileUtils.touch('src2.txt')
+  #   Bundler::FileUtils.mkdir('destdir2')
+  #   Bundler::FileUtils.ln_s('src2.txt', 'destdir2')
+  #   File.symlink?('destdir2/src2.txt') # => true
   #
-  def ln_s(src, dest, force: nil, noop: nil, verbose: nil)
+  # If +src+ is an array of paths to existing files and +dest+ is a directory,
+  # for each child +child+ in +src+ creates a symbolic link <tt>dest/child</tt>
+  # pointing to +child+:
+  #
+  #   Bundler::FileUtils.mkdir('srcdir3')
+  #   Bundler::FileUtils.touch('srcdir3/src0.txt')
+  #   Bundler::FileUtils.touch('srcdir3/src1.txt')
+  #   Bundler::FileUtils.mkdir('destdir3')
+  #   Bundler::FileUtils.ln_s(['srcdir3/src0.txt', 'srcdir3/src1.txt'], 'destdir3')
+  #   File.symlink?('destdir3/src0.txt') # => true
+  #   File.symlink?('destdir3/src1.txt') # => true
+  #
+  # Keyword arguments:
+  #
+  # - <tt>force: true</tt> - overwrites +dest+ if it exists.
+  # - <tt>relative: false</tt> - create links relative to +dest+.
+  # - <tt>noop: true</tt> - does not create links.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     Bundler::FileUtils.ln_s('src0.txt', 'dest0.txt', noop: true, verbose: true)
+  #     Bundler::FileUtils.ln_s('src1.txt', 'destdir1', noop: true, verbose: true)
+  #     Bundler::FileUtils.ln_s('src2.txt', 'dest2.txt', force: true, noop: true, verbose: true)
+  #     Bundler::FileUtils.ln_s(['srcdir3/src0.txt', 'srcdir3/src1.txt'], 'destdir3', noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     ln -s src0.txt dest0.txt
+  #     ln -s src1.txt destdir1
+  #     ln -sf src2.txt dest2.txt
+  #     ln -s srcdir3/src0.txt srcdir3/src1.txt destdir3
+  #
+  # Bundler::FileUtils.symlink is an alias for Bundler::FileUtils.ln_s.
+  #
+  # Related: Bundler::FileUtils.ln_sf.
+  #
+  def ln_s(src, dest, force: nil, relative: false, target_directory: true, noop: nil, verbose: nil)
+    if relative
+      return ln_sr(src, dest, force: force, noop: noop, verbose: verbose)
+    end
     fu_output_message "ln -s#{force ? 'f' : ''} #{[src,dest].flatten.join ' '}" if verbose
     return if noop
     fu_each_src_dest0(src, dest) do |s,d|
@@ -379,29 +727,95 @@ module Bundler::FileUtils
   alias symlink ln_s
   module_function :symlink
 
-  #
-  # :call-seq:
-  #   Bundler::FileUtils.ln_sf(*args)
-  #
-  # Same as
-  #
-  #   Bundler::FileUtils.ln_s(*args, force: true)
+  # Like Bundler::FileUtils.ln_s, but always with keyword argument <tt>force: true</tt> given.
   #
   def ln_sf(src, dest, noop: nil, verbose: nil)
     ln_s src, dest, force: true, noop: noop, verbose: verbose
   end
   module_function :ln_sf
 
+  # Like Bundler::FileUtils.ln_s, but create links relative to +dest+.
+  #
+  def ln_sr(src, dest, target_directory: true, force: nil, noop: nil, verbose: nil)
+    options = "#{force ? 'f' : ''}#{target_directory ? '' : 'T'}"
+    dest = File.path(dest)
+    srcs = Array(src)
+    link = proc do |s, target_dir_p = true|
+      s = File.path(s)
+      if target_dir_p
+        d = File.join(destdirs = dest, File.basename(s))
+      else
+        destdirs = File.dirname(d = dest)
+      end
+      destdirs = fu_split_path(File.realpath(destdirs))
+      if fu_starting_path?(s)
+        srcdirs = fu_split_path((File.realdirpath(s) rescue File.expand_path(s)))
+        base = fu_relative_components_from(srcdirs, destdirs)
+        s = File.join(*base)
+      else
+        srcdirs = fu_clean_components(*fu_split_path(s))
+        base = fu_relative_components_from(fu_split_path(Dir.pwd), destdirs)
+        while srcdirs.first&. == ".." and base.last&.!=("..") and !fu_starting_path?(base.last)
+          srcdirs.shift
+          base.pop
+        end
+        s = File.join(*base, *srcdirs)
+      end
+      fu_output_message "ln -s#{options} #{s} #{d}" if verbose
+      next if noop
+      remove_file d, true if force
+      File.symlink s, d
+    end
+    case srcs.size
+    when 0
+    when 1
+      link[srcs[0], target_directory && File.directory?(dest)]
+    else
+      srcs.each(&link)
+    end
+  end
+  module_function :ln_sr
+
+  # Creates {hard links}[https://en.wikipedia.org/wiki/Hard_link]; returns +nil+.
   #
-  # Hard links a file system entry +src+ to +dest+.
-  # If +src+ is a directory, this method links its contents recursively.
+  # Arguments +src+ and +dest+
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
   #
-  # Both of +src+ and +dest+ must be a path name.
-  # +src+ must exist, +dest+ must not exist.
+  # If +src+ is the path to a file and +dest+ does not exist,
+  # creates a hard link at +dest+ pointing to +src+:
   #
-  # If +dereference_root+ is true, this method dereferences the tree root.
+  #   Bundler::FileUtils.touch('src0.txt')
+  #   File.exist?('dest0.txt') # => false
+  #   Bundler::FileUtils.link_entry('src0.txt', 'dest0.txt')
+  #   File.file?('dest0.txt')  # => true
   #
-  # If +remove_destination+ is true, this method removes each destination file before copy.
+  # If +src+ is the path to a directory and +dest+ does not exist,
+  # recursively creates hard links at +dest+ pointing to paths in +src+:
+  #
+  #   Bundler::FileUtils.mkdir_p(['src1/dir0', 'src1/dir1'])
+  #   src_file_paths = [
+  #     'src1/dir0/t0.txt',
+  #     'src1/dir0/t1.txt',
+  #     'src1/dir1/t2.txt',
+  #     'src1/dir1/t3.txt',
+  #     ]
+  #   Bundler::FileUtils.touch(src_file_paths)
+  #   File.directory?('dest1')        # => true
+  #   Bundler::FileUtils.link_entry('src1', 'dest1')
+  #   File.file?('dest1/dir0/t0.txt') # => true
+  #   File.file?('dest1/dir0/t1.txt') # => true
+  #   File.file?('dest1/dir1/t2.txt') # => true
+  #   File.file?('dest1/dir1/t3.txt') # => true
+  #
+  # Keyword arguments:
+  #
+  # - <tt>dereference_root: true</tt> - dereferences +src+ if it is a symbolic link.
+  # - <tt>remove_destination: true</tt> - removes +dest+ before creating links.
+  #
+  # Raises an exception if +dest+ is the path to an existing file or directory
+  # and keyword argument <tt>remove_destination: true</tt> is not given.
+  #
+  # Related: Bundler::FileUtils.ln (has different options).
   #
   def link_entry(src, dest, dereference_root = false, remove_destination = false)
     Entry_.new(src, nil, dereference_root).traverse do |ent|
@@ -412,16 +826,59 @@ module Bundler::FileUtils
   end
   module_function :link_entry
 
+  # Copies files.
+  #
+  # Arguments +src+ (a single path or an array of paths)
+  # and +dest+ (a single path)
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # If +src+ is the path to a file and +dest+ is not the path to a directory,
+  # copies +src+ to +dest+:
+  #
+  #   Bundler::FileUtils.touch('src0.txt')
+  #   File.exist?('dest0.txt') # => false
+  #   Bundler::FileUtils.cp('src0.txt', 'dest0.txt')
+  #   File.file?('dest0.txt')  # => true
   #
-  # Copies a file content +src+ to +dest+.  If +dest+ is a directory,
-  # copies +src+ to +dest/src+.
+  # If +src+ is the path to a file and +dest+ is the path to a directory,
+  # copies +src+ to <tt>dest/src</tt>:
   #
-  # If +src+ is a list of files, then +dest+ must be a directory.
+  #   Bundler::FileUtils.touch('src1.txt')
+  #   Bundler::FileUtils.mkdir('dest1')
+  #   Bundler::FileUtils.cp('src1.txt', 'dest1')
+  #   File.file?('dest1/src1.txt') # => true
   #
-  #   Bundler::FileUtils.cp 'eval.c', 'eval.c.org'
-  #   Bundler::FileUtils.cp %w(cgi.rb complex.rb date.rb), '/usr/lib/ruby/1.6'
-  #   Bundler::FileUtils.cp %w(cgi.rb complex.rb date.rb), '/usr/lib/ruby/1.6', verbose: true
-  #   Bundler::FileUtils.cp 'symlink', 'dest'   # copy content, "dest" is not a symlink
+  # If +src+ is an array of paths to files and +dest+ is the path to a directory,
+  # copies from each +src+ to +dest+:
+  #
+  #   src_file_paths = ['src2.txt', 'src2.dat']
+  #   Bundler::FileUtils.touch(src_file_paths)
+  #   Bundler::FileUtils.mkdir('dest2')
+  #   Bundler::FileUtils.cp(src_file_paths, 'dest2')
+  #   File.file?('dest2/src2.txt') # => true
+  #   File.file?('dest2/src2.dat') # => true
+  #
+  # Keyword arguments:
+  #
+  # - <tt>preserve: true</tt> - preserves file times.
+  # - <tt>noop: true</tt> - does not copy files.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     Bundler::FileUtils.cp('src0.txt', 'dest0.txt', noop: true, verbose: true)
+  #     Bundler::FileUtils.cp('src1.txt', 'dest1', noop: true, verbose: true)
+  #     Bundler::FileUtils.cp(src_file_paths, 'dest2', noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     cp src0.txt dest0.txt
+  #     cp src1.txt dest1
+  #     cp src2.txt src2.dat dest2
+  #
+  # Raises an exception if +src+ is a directory.
+  #
+  # Bundler::FileUtils.copy is an alias for Bundler::FileUtils.cp.
+  #
+  # Related: {methods for copying}[rdoc-ref:FileUtils@Copying].
   #
   def cp(src, dest, preserve: nil, noop: nil, verbose: nil)
     fu_output_message "cp#{preserve ? ' -p' : ''} #{[src,dest].flatten.join ' '}" if verbose
@@ -435,30 +892,105 @@ module Bundler::FileUtils
   alias copy cp
   module_function :copy
 
-  #
-  # Copies +src+ to +dest+. If +src+ is a directory, this method copies
-  # all its contents recursively. If +dest+ is a directory, copies
-  # +src+ to +dest/src+.
-  #
-  # +src+ can be a list of files.
-  #
-  # If +dereference_root+ is true, this method dereference tree root.
-  #
-  # If +remove_destination+ is true, this method removes each destination file before copy.
-  #
-  #   # Installing Ruby library "mylib" under the site_ruby
-  #   Bundler::FileUtils.rm_r site_ruby + '/mylib', force: true
-  #   Bundler::FileUtils.cp_r 'lib/', site_ruby + '/mylib'
-  #
-  #   # Examples of copying several files to target directory.
-  #   Bundler::FileUtils.cp_r %w(mail.rb field.rb debug/), site_ruby + '/tmail'
-  #   Bundler::FileUtils.cp_r Dir.glob('*.rb'), '/home/foo/lib/ruby', noop: true, verbose: true
-  #
-  #   # If you want to copy all contents of a directory instead of the
-  #   # directory itself, c.f. src/x -> dest/x, src/y -> dest/y,
-  #   # use following code.
-  #   Bundler::FileUtils.cp_r 'src/.', 'dest'     # cp_r('src', 'dest') makes dest/src,
-  #                                      # but this doesn't.
+  # Recursively copies files.
+  #
+  # Arguments +src+ (a single path or an array of paths)
+  # and +dest+ (a single path)
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # The mode, owner, and group are retained in the copy;
+  # to change those, use Bundler::FileUtils.install instead.
+  #
+  # If +src+ is the path to a file and +dest+ is not the path to a directory,
+  # copies +src+ to +dest+:
+  #
+  #   Bundler::FileUtils.touch('src0.txt')
+  #   File.exist?('dest0.txt') # => false
+  #   Bundler::FileUtils.cp_r('src0.txt', 'dest0.txt')
+  #   File.file?('dest0.txt')  # => true
+  #
+  # If +src+ is the path to a file and +dest+ is the path to a directory,
+  # copies +src+ to <tt>dest/src</tt>:
+  #
+  #   Bundler::FileUtils.touch('src1.txt')
+  #   Bundler::FileUtils.mkdir('dest1')
+  #   Bundler::FileUtils.cp_r('src1.txt', 'dest1')
+  #   File.file?('dest1/src1.txt') # => true
+  #
+  # If +src+ is the path to a directory and +dest+ does not exist,
+  # recursively copies +src+ to +dest+:
+  #
+  #   tree('src2')
+  #   # => src2
+  #   #    |-- dir0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- dir1
+  #   #    |-- src2.txt
+  #   #    `-- src3.txt
+  #   Bundler::FileUtils.exist?('dest2') # => false
+  #   Bundler::FileUtils.cp_r('src2', 'dest2')
+  #   tree('dest2')
+  #   # => dest2
+  #   #    |-- dir0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- dir1
+  #   #    |-- src2.txt
+  #   #    `-- src3.txt
+  #
+  # If +src+ and +dest+ are paths to directories,
+  # recursively copies +src+ to <tt>dest/src</tt>:
+  #
+  #   tree('src3')
+  #   # => src3
+  #   #    |-- dir0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- dir1
+  #   #    |-- src2.txt
+  #   #    `-- src3.txt
+  #   Bundler::FileUtils.mkdir('dest3')
+  #   Bundler::FileUtils.cp_r('src3', 'dest3')
+  #   tree('dest3')
+  #   # => dest3
+  #   #    `-- src3
+  #   #      |-- dir0
+  #   #      |   |-- src0.txt
+  #   #      |   `-- src1.txt
+  #   #      `-- dir1
+  #   #          |-- src2.txt
+  #   #          `-- src3.txt
+  #
+  # If +src+ is an array of paths and +dest+ is a directory,
+  # recursively copies from each path in +src+ to +dest+;
+  # the paths in +src+ may point to files and/or directories.
+  #
+  # Keyword arguments:
+  #
+  # - <tt>dereference_root: false</tt> - if +src+ is a symbolic link,
+  #   does not dereference it.
+  # - <tt>noop: true</tt> - does not copy files.
+  # - <tt>preserve: true</tt> - preserves file times.
+  # - <tt>remove_destination: true</tt> - removes +dest+ before copying files.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     Bundler::FileUtils.cp_r('src0.txt', 'dest0.txt', noop: true, verbose: true)
+  #     Bundler::FileUtils.cp_r('src1.txt', 'dest1', noop: true, verbose: true)
+  #     Bundler::FileUtils.cp_r('src2', 'dest2', noop: true, verbose: true)
+  #     Bundler::FileUtils.cp_r('src3', 'dest3', noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     cp -r src0.txt dest0.txt
+  #     cp -r src1.txt dest1
+  #     cp -r src2 dest2
+  #     cp -r src3 dest3
+  #
+  # Raises an exception of +src+ is the path to a directory
+  # and +dest+ is the path to a file.
+  #
+  # Related: {methods for copying}[rdoc-ref:FileUtils@Copying].
   #
   def cp_r(src, dest, preserve: nil, noop: nil, verbose: nil,
            dereference_root: true, remove_destination: nil)
@@ -470,21 +1002,50 @@ module Bundler::FileUtils
   end
   module_function :cp_r
 
+  # Recursively copies files from +src+ to +dest+.
+  #
+  # Arguments +src+ and +dest+
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
   #
-  # Copies a file system entry +src+ to +dest+.
-  # If +src+ is a directory, this method copies its contents recursively.
-  # This method preserves file types, c.f. symlink, directory...
-  # (FIFO, device files and etc. are not supported yet)
+  # If +src+ is the path to a file, copies +src+ to +dest+:
   #
-  # Both of +src+ and +dest+ must be a path name.
-  # +src+ must exist, +dest+ must not exist.
+  #   Bundler::FileUtils.touch('src0.txt')
+  #   File.exist?('dest0.txt') # => false
+  #   Bundler::FileUtils.copy_entry('src0.txt', 'dest0.txt')
+  #   File.file?('dest0.txt')  # => true
   #
-  # If +preserve+ is true, this method preserves owner, group, and
-  # modified time.  Permissions are copied regardless +preserve+.
+  # If +src+ is a directory, recursively copies +src+ to +dest+:
   #
-  # If +dereference_root+ is true, this method dereference tree root.
+  #   tree('src1')
+  #   # => src1
+  #   #    |-- dir0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- dir1
+  #   #        |-- src2.txt
+  #   #        `-- src3.txt
+  #   Bundler::FileUtils.copy_entry('src1', 'dest1')
+  #   tree('dest1')
+  #   # => dest1
+  #   #    |-- dir0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- dir1
+  #   #        |-- src2.txt
+  #   #        `-- src3.txt
   #
-  # If +remove_destination+ is true, this method removes each destination file before copy.
+  # The recursive copying preserves file types for regular files,
+  # directories, and symbolic links;
+  # other file types (FIFO streams, device files, etc.) are not supported.
+  #
+  # Keyword arguments:
+  #
+  # - <tt>dereference_root: true</tt> - if +src+ is a symbolic link,
+  #   follows the link.
+  # - <tt>preserve: true</tt> - preserves file times.
+  # - <tt>remove_destination: true</tt> - removes +dest+ before copying files.
+  #
+  # Related: {methods for copying}[rdoc-ref:FileUtils@Copying].
   #
   def copy_entry(src, dest, preserve = false, dereference_root = false, remove_destination = false)
     if dereference_root
@@ -502,9 +1063,25 @@ module Bundler::FileUtils
   end
   module_function :copy_entry
 
+  # Copies file from +src+ to +dest+, which should not be directories.
+  #
+  # Arguments +src+ and +dest+
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # Examples:
   #
-  # Copies file contents of +src+ to +dest+.
-  # Both of +src+ and +dest+ must be a path name.
+  #   Bundler::FileUtils.touch('src0.txt')
+  #   Bundler::FileUtils.copy_file('src0.txt', 'dest0.txt')
+  #   File.file?('dest0.txt') # => true
+  #
+  # Keyword arguments:
+  #
+  # - <tt>dereference: false</tt> - if +src+ is a symbolic link,
+  #   does not follow the link.
+  # - <tt>preserve: true</tt> - preserves file times.
+  # - <tt>remove_destination: true</tt> - removes +dest+ before copying files.
+  #
+  # Related: {methods for copying}[rdoc-ref:FileUtils@Copying].
   #
   def copy_file(src, dest, preserve = false, dereference = true)
     ent = Entry_.new(src, nil, dereference)
@@ -513,25 +1090,81 @@ module Bundler::FileUtils
   end
   module_function :copy_file
 
+  # Copies \IO stream +src+ to \IO stream +dest+ via
+  # {IO.copy_stream}[rdoc-ref:IO.copy_stream].
   #
-  # Copies stream +src+ to +dest+.
-  # +src+ must respond to #read(n) and
-  # +dest+ must respond to #write(str).
+  # Related: {methods for copying}[rdoc-ref:FileUtils@Copying].
   #
   def copy_stream(src, dest)
     IO.copy_stream(src, dest)
   end
   module_function :copy_stream
 
-  #
-  # Moves file(s) +src+ to +dest+.  If +file+ and +dest+ exist on the different
-  # disk partition, the file is copied then the original file is removed.
-  #
-  #   Bundler::FileUtils.mv 'badname.rb', 'goodname.rb'
-  #   Bundler::FileUtils.mv 'stuff.rb', '/notexist/lib/ruby', force: true  # no error
-  #
-  #   Bundler::FileUtils.mv %w(junk.txt dust.txt), '/home/foo/.trash/'
-  #   Bundler::FileUtils.mv Dir.glob('test*.rb'), 'test', noop: true, verbose: true
+  # Moves entries.
+  #
+  # Arguments +src+ (a single path or an array of paths)
+  # and +dest+ (a single path)
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # If +src+ and +dest+ are on different file systems,
+  # first copies, then removes +src+.
+  #
+  # May cause a local vulnerability if not called with keyword argument
+  # <tt>secure: true</tt>;
+  # see {Avoiding the TOCTTOU Vulnerability}[rdoc-ref:FileUtils@Avoiding+the+TOCTTOU+Vulnerability].
+  #
+  # If +src+ is the path to a single file or directory and +dest+ does not exist,
+  # moves +src+ to +dest+:
+  #
+  #   tree('src0')
+  #   # => src0
+  #   #    |-- src0.txt
+  #   #    `-- src1.txt
+  #   File.exist?('dest0') # => false
+  #   Bundler::FileUtils.mv('src0', 'dest0')
+  #   File.exist?('src0')  # => false
+  #   tree('dest0')
+  #   # => dest0
+  #   #    |-- src0.txt
+  #   #    `-- src1.txt
+  #
+  # If +src+ is an array of paths to files and directories
+  # and +dest+ is the path to a directory,
+  # copies from each path in the array to +dest+:
+  #
+  #   File.file?('src1.txt') # => true
+  #   tree('src1')
+  #   # => src1
+  #   #    |-- src.dat
+  #   #    `-- src.txt
+  #   Dir.empty?('dest1')    # => true
+  #   Bundler::FileUtils.mv(['src1.txt', 'src1'], 'dest1')
+  #   tree('dest1')
+  #   # => dest1
+  #   #    |-- src1
+  #   #    |   |-- src.dat
+  #   #    |   `-- src.txt
+  #   #    `-- src1.txt
+  #
+  # Keyword arguments:
+  #
+  # - <tt>force: true</tt> - if the move includes removing +src+
+  #   (that is, if +src+ and +dest+ are on different file systems),
+  #   ignores raised exceptions of StandardError and its descendants.
+  # - <tt>noop: true</tt> - does not move files.
+  # - <tt>secure: true</tt> - removes +src+ securely;
+  #   see details at Bundler::FileUtils.remove_entry_secure.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     Bundler::FileUtils.mv('src0', 'dest0', noop: true, verbose: true)
+  #     Bundler::FileUtils.mv(['src1.txt', 'src1'], 'dest1', noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     mv src0 dest0
+  #     mv src1.txt src1 dest1
+  #
+  # Bundler::FileUtils.move is an alias for Bundler::FileUtils.mv.
   #
   def mv(src, dest, force: nil, noop: nil, verbose: nil, secure: nil)
     fu_output_message "mv#{force ? ' -f' : ''} #{[src,dest].flatten.join ' '}" if verbose
@@ -565,13 +1198,34 @@ module Bundler::FileUtils
   alias move mv
   module_function :move
 
+  # Removes entries at the paths in the given +list+
+  # (a single path or an array of paths)
+  # returns +list+, if it is an array, <tt>[list]</tt> otherwise.
+  #
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # With no keyword arguments, removes files at the paths given in +list+:
+  #
+  #   Bundler::FileUtils.touch(['src0.txt', 'src0.dat'])
+  #   Bundler::FileUtils.rm(['src0.dat', 'src0.txt']) # => ["src0.dat", "src0.txt"]
+  #
+  # Keyword arguments:
+  #
+  # - <tt>force: true</tt> - ignores raised exceptions of StandardError
+  #   and its descendants.
+  # - <tt>noop: true</tt> - does not remove files; returns +nil+.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     Bundler::FileUtils.rm(['src0.dat', 'src0.txt'], noop: true, verbose: true)
   #
-  # Remove file(s) specified in +list+.  This method cannot remove directories.
-  # All StandardErrors are ignored when the :force option is set.
+  #   Output:
   #
-  #   Bundler::FileUtils.rm %w( junk.txt dust.txt )
-  #   Bundler::FileUtils.rm Dir.glob('*.so')
-  #   Bundler::FileUtils.rm 'NotExistFile', force: true   # never raises exception
+  #     rm src0.dat src0.txt
+  #
+  # Bundler::FileUtils.remove is an alias for Bundler::FileUtils.rm.
+  #
+  # Related: {methods for deleting}[rdoc-ref:FileUtils@Deleting].
   #
   def rm(list, force: nil, noop: nil, verbose: nil)
     list = fu_list(list)
@@ -587,10 +1241,18 @@ module Bundler::FileUtils
   alias remove rm
   module_function :remove
 
+  # Equivalent to:
+  #
+  #   Bundler::FileUtils.rm(list, force: true, **kwargs)
+  #
+  # Argument +list+ (a single path or an array of paths)
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # See Bundler::FileUtils.rm for keyword arguments.
   #
-  # Equivalent to
+  # Bundler::FileUtils.safe_unlink is an alias for Bundler::FileUtils.rm_f.
   #
-  #   Bundler::FileUtils.rm(list, force: true)
+  # Related: {methods for deleting}[rdoc-ref:FileUtils@Deleting].
   #
   def rm_f(list, noop: nil, verbose: nil)
     rm list, force: true, noop: noop, verbose: verbose
@@ -600,24 +1262,55 @@ module Bundler::FileUtils
   alias safe_unlink rm_f
   module_function :safe_unlink
 
+  # Removes entries at the paths in the given +list+
+  # (a single path or an array of paths);
+  # returns +list+, if it is an array, <tt>[list]</tt> otherwise.
+  #
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # May cause a local vulnerability if not called with keyword argument
+  # <tt>secure: true</tt>;
+  # see {Avoiding the TOCTTOU Vulnerability}[rdoc-ref:FileUtils@Avoiding+the+TOCTTOU+Vulnerability].
+  #
+  # For each file path, removes the file at that path:
+  #
+  #   Bundler::FileUtils.touch(['src0.txt', 'src0.dat'])
+  #   Bundler::FileUtils.rm_r(['src0.dat', 'src0.txt'])
+  #   File.exist?('src0.txt') # => false
+  #   File.exist?('src0.dat') # => false
   #
-  # remove files +list+[0] +list+[1]... If +list+[n] is a directory,
-  # removes its all contents recursively. This method ignores
-  # StandardError when :force option is set.
+  # For each directory path, recursively removes files and directories:
   #
-  #   Bundler::FileUtils.rm_r Dir.glob('/tmp/*')
-  #   Bundler::FileUtils.rm_r 'some_dir', force: true
+  #   tree('src1')
+  #   # => src1
+  #   #    |-- dir0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- dir1
+  #   #        |-- src2.txt
+  #   #        `-- src3.txt
+  #   Bundler::FileUtils.rm_r('src1')
+  #   File.exist?('src1') # => false
   #
-  # WARNING: This method causes local vulnerability
-  # if one of parent directories or removing directory tree are world
-  # writable (including /tmp, whose permission is 1777), and the current
-  # process has strong privilege such as Unix super user (root), and the
-  # system has symbolic link.  For secure removing, read the documentation
-  # of remove_entry_secure carefully, and set :secure option to true.
-  # Default is <tt>secure: false</tt>.
+  # Keyword arguments:
   #
-  # NOTE: This method calls remove_entry_secure if :secure option is set.
-  # See also remove_entry_secure.
+  # - <tt>force: true</tt> - ignores raised exceptions of StandardError
+  #   and its descendants.
+  # - <tt>noop: true</tt> - does not remove entries; returns +nil+.
+  # - <tt>secure: true</tt> - removes +src+ securely;
+  #   see details at Bundler::FileUtils.remove_entry_secure.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     Bundler::FileUtils.rm_r(['src0.dat', 'src0.txt'], noop: true, verbose: true)
+  #     Bundler::FileUtils.rm_r('src1', noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     rm -r src0.dat src0.txt
+  #     rm -r src1
+  #
+  # Related: {methods for deleting}[rdoc-ref:FileUtils@Deleting].
   #
   def rm_r(list, force: nil, noop: nil, verbose: nil, secure: nil)
     list = fu_list(list)
@@ -633,13 +1326,22 @@ module Bundler::FileUtils
   end
   module_function :rm_r
 
+  # Equivalent to:
   #
-  # Equivalent to
+  #   Bundler::FileUtils.rm_r(list, force: true, **kwargs)
   #
-  #   Bundler::FileUtils.rm_r(list, force: true)
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
   #
-  # WARNING: This method causes local vulnerability.
-  # Read the documentation of rm_r first.
+  # May cause a local vulnerability if not called with keyword argument
+  # <tt>secure: true</tt>;
+  # see {Avoiding the TOCTTOU Vulnerability}[rdoc-ref:FileUtils@Avoiding+the+TOCTTOU+Vulnerability].
+  #
+  # See Bundler::FileUtils.rm_r for keyword arguments.
+  #
+  # Bundler::FileUtils.rmtree is an alias for Bundler::FileUtils.rm_rf.
+  #
+  # Related: {methods for deleting}[rdoc-ref:FileUtils@Deleting].
   #
   def rm_rf(list, noop: nil, verbose: nil, secure: nil)
     rm_r list, force: true, noop: noop, verbose: verbose, secure: secure
@@ -649,37 +1351,20 @@ module Bundler::FileUtils
   alias rmtree rm_rf
   module_function :rmtree
 
+  # Securely removes the entry given by +path+,
+  # which should be the entry for a regular file, a symbolic link,
+  # or a directory.
   #
-  # This method removes a file system entry +path+.  +path+ shall be a
-  # regular file, a directory, or something.  If +path+ is a directory,
-  # remove it recursively.  This method is required to avoid TOCTTOU
-  # (time-of-check-to-time-of-use) local security vulnerability of rm_r.
-  # #rm_r causes security hole when:
-  #
-  # * Parent directory is world writable (including /tmp).
-  # * Removing directory tree includes world writable directory.
-  # * The system has symbolic link.
+  # Argument +path+
+  # should be {interpretable as a path}[rdoc-ref:FileUtils@Path+Arguments].
   #
-  # To avoid this security hole, this method applies special preprocess.
-  # If +path+ is a directory, this method chown(2) and chmod(2) all
-  # removing directories.  This requires the current process is the
-  # owner of the removing whole directory tree, or is the super user (root).
+  # Avoids a local vulnerability that can exist in certain circumstances;
+  # see {Avoiding the TOCTTOU Vulnerability}[rdoc-ref:FileUtils@Avoiding+the+TOCTTOU+Vulnerability].
   #
-  # WARNING: You must ensure that *ALL* parent directories cannot be
-  # moved by other untrusted users.  For example, parent directories
-  # should not be owned by untrusted users, and should not be world
-  # writable except when the sticky bit set.
+  # Optional argument +force+ specifies whether to ignore
+  # raised exceptions of StandardError and its descendants.
   #
-  # WARNING: Only the owner of the removing directory tree, or Unix super
-  # user (root) should invoke this method.  Otherwise this method does not
-  # work.
-  #
-  # For details of this security vulnerability, see Perl's case:
-  #
-  # * https://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2005-0448
-  # * https://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2004-0452
-  #
-  # For fileutils.rb, this vulnerability is reported in [ruby-dev:26100].
+  # Related: {methods for deleting}[rdoc-ref:FileUtils@Deleting].
   #
   def remove_entry_secure(path, force = false)
     unless fu_have_symlink?
@@ -767,12 +1452,17 @@ module Bundler::FileUtils
   end
   private_module_function :fu_stat_identical_entry?
 
+  # Removes the entry given by +path+,
+  # which should be the entry for a regular file, a symbolic link,
+  # or a directory.
   #
-  # This method removes a file system entry +path+.
-  # +path+ might be a regular file, a directory, or something.
-  # If +path+ is a directory, remove it recursively.
+  # Argument +path+
+  # should be {interpretable as a path}[rdoc-ref:FileUtils@Path+Arguments].
   #
-  # See also remove_entry_secure.
+  # Optional argument +force+ specifies whether to ignore
+  # raised exceptions of StandardError and its descendants.
+  #
+  # Related: Bundler::FileUtils.remove_entry_secure.
   #
   def remove_entry(path, force = false)
     Entry_.new(path).postorder_traverse do |ent|
@@ -787,9 +1477,16 @@ module Bundler::FileUtils
   end
   module_function :remove_entry
 
+  # Removes the file entry given by +path+,
+  # which should be the entry for a regular file or a symbolic link.
+  #
+  # Argument +path+
+  # should be {interpretable as a path}[rdoc-ref:FileUtils@Path+Arguments].
   #
-  # Removes a file +path+.
-  # This method ignores StandardError if +force+ is true.
+  # Optional argument +force+ specifies whether to ignore
+  # raised exceptions of StandardError and its descendants.
+  #
+  # Related: {methods for deleting}[rdoc-ref:FileUtils@Deleting].
   #
   def remove_file(path, force = false)
     Entry_.new(path).remove_file
@@ -798,20 +1495,32 @@ module Bundler::FileUtils
   end
   module_function :remove_file
 
+  # Recursively removes the directory entry given by +path+,
+  # which should be the entry for a regular file, a symbolic link,
+  # or a directory.
+  #
+  # Argument +path+
+  # should be {interpretable as a path}[rdoc-ref:FileUtils@Path+Arguments].
   #
-  # Removes a directory +dir+ and its contents recursively.
-  # This method ignores StandardError if +force+ is true.
+  # Optional argument +force+ specifies whether to ignore
+  # raised exceptions of StandardError and its descendants.
+  #
+  # Related: {methods for deleting}[rdoc-ref:FileUtils@Deleting].
   #
   def remove_dir(path, force = false)
     remove_entry path, force   # FIXME?? check if it is a directory
   end
   module_function :remove_dir
 
+  # Returns +true+ if the contents of files +a+ and +b+ are identical,
+  # +false+ otherwise.
+  #
+  # Arguments +a+ and +b+
+  # should be {interpretable as a path}[rdoc-ref:FileUtils@Path+Arguments].
   #
-  # Returns true if the contents of a file +a+ and a file +b+ are identical.
+  # Bundler::FileUtils.identical? and Bundler::FileUtils.cmp are aliases for Bundler::FileUtils.compare_file.
   #
-  #   Bundler::FileUtils.compare_file('somefile', 'somefile')       #=> true
-  #   Bundler::FileUtils.compare_file('/dev/null', '/dev/urandom')  #=> false
+  # Related: Bundler::FileUtils.compare_stream.
   #
   def compare_file(a, b)
     return false unless File.size(a) == File.size(b)
@@ -828,19 +1537,19 @@ module Bundler::FileUtils
   module_function :identical?
   module_function :cmp
 
+  # Returns +true+ if the contents of streams +a+ and +b+ are identical,
+  # +false+ otherwise.
   #
-  # Returns true if the contents of a stream +a+ and +b+ are identical.
+  # Arguments +a+ and +b+
+  # should be {interpretable as a path}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # Related: Bundler::FileUtils.compare_file.
   #
   def compare_stream(a, b)
     bsize = fu_stream_blksize(a, b)
 
-    if RUBY_VERSION > "2.4"
-      sa = String.new(capacity: bsize)
-      sb = String.new(capacity: bsize)
-    else
-      sa = String.new
-      sb = String.new
-    end
+    sa = String.new(capacity: bsize)
+    sb = String.new(capacity: bsize)
 
     begin
       a.read(bsize, sa)
@@ -851,13 +1560,69 @@ module Bundler::FileUtils
   end
   module_function :compare_stream
 
+  # Copies a file entry.
+  # See {install(1)}[https://man7.org/linux/man-pages/man1/install.1.html].
+  #
+  # Arguments +src+ (a single path or an array of paths)
+  # and +dest+ (a single path)
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments];
+  #
+  # If the entry at +dest+ does not exist, copies from +src+ to +dest+:
+  #
+  #   File.read('src0.txt')    # => "aaa\n"
+  #   File.exist?('dest0.txt') # => false
+  #   Bundler::FileUtils.install('src0.txt', 'dest0.txt')
+  #   File.read('dest0.txt')   # => "aaa\n"
+  #
+  # If +dest+ is a file entry, copies from +src+ to +dest+, overwriting:
+  #
+  #   File.read('src1.txt')  # => "aaa\n"
+  #   File.read('dest1.txt') # => "bbb\n"
+  #   Bundler::FileUtils.install('src1.txt', 'dest1.txt')
+  #   File.read('dest1.txt') # => "aaa\n"
   #
-  # If +src+ is not same as +dest+, copies it and changes the permission
-  # mode to +mode+.  If +dest+ is a directory, destination is +dest+/+src+.
-  # This method removes destination before copy.
+  # If +dest+ is a directory entry, copies from +src+ to <tt>dest/src</tt>,
+  # overwriting if necessary:
   #
-  #   Bundler::FileUtils.install 'ruby', '/usr/local/bin/ruby', mode: 0755, verbose: true
-  #   Bundler::FileUtils.install 'lib.rb', '/usr/local/lib/ruby/site_ruby', verbose: true
+  #   File.read('src2.txt')       # => "aaa\n"
+  #   File.read('dest2/src2.txt') # => "bbb\n"
+  #   Bundler::FileUtils.install('src2.txt', 'dest2')
+  #   File.read('dest2/src2.txt') # => "aaa\n"
+  #
+  # If +src+ is an array of paths and +dest+ points to a directory,
+  # copies each path +path+ in +src+ to <tt>dest/path</tt>:
+  #
+  #   File.file?('src3.txt') # => true
+  #   File.file?('src3.dat') # => true
+  #   Bundler::FileUtils.mkdir('dest3')
+  #   Bundler::FileUtils.install(['src3.txt', 'src3.dat'], 'dest3')
+  #   File.file?('dest3/src3.txt') # => true
+  #   File.file?('dest3/src3.dat') # => true
+  #
+  # Keyword arguments:
+  #
+  # - <tt>group: <i>group</i></tt> - changes the group if not +nil+,
+  #   using {File.chown}[rdoc-ref:File.chown].
+  # - <tt>mode: <i>permissions</i></tt> - changes the permissions.
+  #   using {File.chmod}[rdoc-ref:File.chmod].
+  # - <tt>noop: true</tt> - does not copy entries; returns +nil+.
+  # - <tt>owner: <i>owner</i></tt> - changes the owner if not +nil+,
+  #   using {File.chown}[rdoc-ref:File.chown].
+  # - <tt>preserve: true</tt> - preserve timestamps
+  #   using {File.utime}[rdoc-ref:File.utime].
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     Bundler::FileUtils.install('src0.txt', 'dest0.txt', noop: true, verbose: true)
+  #     Bundler::FileUtils.install('src1.txt', 'dest1.txt', noop: true, verbose: true)
+  #     Bundler::FileUtils.install('src2.txt', 'dest2', noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     install -c src0.txt dest0.txt
+  #     install -c src1.txt dest1.txt
+  #     install -c src2.txt dest2
+  #
+  # Related: {methods for copying}[rdoc-ref:FileUtils@Copying].
   #
   def install(src, dest, mode: nil, owner: nil, group: nil, preserve: nil,
               noop: nil, verbose: nil)
@@ -917,11 +1682,8 @@ module Bundler::FileUtils
   private_module_function :apply_mask
 
   def symbolic_modes_to_i(mode_sym, path)  #:nodoc:
-    mode = if File::Stat === path
-             path.mode
-           else
-             File.stat(path).mode
-           end
+    path = File.stat(path) unless File::Stat === path
+    mode = path.mode
     mode_sym.split(/,/).inject(mode & 07777) do |current_mode, clause|
       target, *actions = clause.split(/([=+-])/)
       raise ArgumentError, "invalid file mode: #{mode_sym}" if actions.empty?
@@ -938,7 +1700,7 @@ module Bundler::FileUtils
           when "x"
             mask | 0111
           when "X"
-            if FileTest.directory? path
+            if path.directory?
               mask | 0111
             else
               mask
@@ -978,37 +1740,78 @@ module Bundler::FileUtils
   end
   private_module_function :mode_to_s
 
+  # Changes permissions on the entries at the paths given in +list+
+  # (a single path or an array of paths)
+  # to the permissions given by +mode+;
+  # returns +list+ if it is an array, <tt>[list]</tt> otherwise:
+  #
+  # - Modifies each entry that is a regular file using
+  #   {File.chmod}[rdoc-ref:File.chmod].
+  # - Modifies each entry that is a symbolic link using
+  #   {File.lchmod}[rdoc-ref:File.lchmod].
+  #
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # Argument +mode+ may be either an integer or a string:
+  #
+  # - \Integer +mode+: represents the permission bits to be set:
+  #
+  #     Bundler::FileUtils.chmod(0755, 'src0.txt')
+  #     Bundler::FileUtils.chmod(0644, ['src0.txt', 'src0.dat'])
+  #
+  # - \String +mode+: represents the permissions to be set:
+  #
+  #   The string is of the form <tt>[targets][[operator][perms[,perms]]</tt>, where:
+  #
+  #   - +targets+ may be any combination of these letters:
+  #
+  #     - <tt>'u'</tt>: permissions apply to the file's owner.
+  #     - <tt>'g'</tt>: permissions apply to users in the file's group.
+  #     - <tt>'o'</tt>: permissions apply to other users not in the file's group.
+  #     - <tt>'a'</tt> (the default): permissions apply to all users.
+  #
+  #   - +operator+ may be one of these letters:
+  #
+  #     - <tt>'+'</tt>: adds permissions.
+  #     - <tt>'-'</tt>: removes permissions.
+  #     - <tt>'='</tt>: sets (replaces) permissions.
+  #
+  #   - +perms+ (may be repeated, with separating commas)
+  #     may be any combination of these letters:
+  #
+  #     - <tt>'r'</tt>: Read.
+  #     - <tt>'w'</tt>: Write.
+  #     - <tt>'x'</tt>: Execute (search, for a directory).
+  #     - <tt>'X'</tt>: Search (for a directories only;
+  #       must be used with <tt>'+'</tt>)
+  #     - <tt>'s'</tt>: Uid or gid.
+  #     - <tt>'t'</tt>: Sticky bit.
+  #
+  #   Examples:
+  #
+  #     Bundler::FileUtils.chmod('u=wrx,go=rx', 'src1.txt')
+  #     Bundler::FileUtils.chmod('u=wrx,go=rx', '/usr/bin/ruby')
+  #
+  # Keyword arguments:
+  #
+  # - <tt>noop: true</tt> - does not change permissions; returns +nil+.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     Bundler::FileUtils.chmod(0755, 'src0.txt', noop: true, verbose: true)
+  #     Bundler::FileUtils.chmod(0644, ['src0.txt', 'src0.dat'], noop: true, verbose: true)
+  #     Bundler::FileUtils.chmod('u=wrx,go=rx', 'src1.txt', noop: true, verbose: true)
+  #     Bundler::FileUtils.chmod('u=wrx,go=rx', '/usr/bin/ruby', noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     chmod 755 src0.txt
+  #     chmod 644 src0.txt src0.dat
+  #     chmod u=wrx,go=rx src1.txt
+  #     chmod u=wrx,go=rx /usr/bin/ruby
+  #
+  # Related: Bundler::FileUtils.chmod_R.
   #
-  # Changes permission bits on the named files (in +list+) to the bit pattern
-  # represented by +mode+.
-  #
-  # +mode+ is the symbolic and absolute mode can be used.
-  #
-  # Absolute mode is
-  #   Bundler::FileUtils.chmod 0755, 'somecommand'
-  #   Bundler::FileUtils.chmod 0644, %w(my.rb your.rb his.rb her.rb)
-  #   Bundler::FileUtils.chmod 0755, '/usr/bin/ruby', verbose: true
-  #
-  # Symbolic mode is
-  #   Bundler::FileUtils.chmod "u=wrx,go=rx", 'somecommand'
-  #   Bundler::FileUtils.chmod "u=wr,go=rr", %w(my.rb your.rb his.rb her.rb)
-  #   Bundler::FileUtils.chmod "u=wrx,go=rx", '/usr/bin/ruby', verbose: true
-  #
-  # "a" :: is user, group, other mask.
-  # "u" :: is user's mask.
-  # "g" :: is group's mask.
-  # "o" :: is other's mask.
-  # "w" :: is write permission.
-  # "r" :: is read permission.
-  # "x" :: is execute permission.
-  # "X" ::
-  #   is execute permission for directories only, must be used in conjunction with "+"
-  # "s" :: is uid, gid.
-  # "t" :: is sticky bit.
-  # "+" :: is added to a class given the specified mode.
-  # "-" :: Is removed from a given class given mode.
-  # "=" :: Is the exact nature of the class will be given a specified mode.
-
   def chmod(mode, list, noop: nil, verbose: nil)
     list = fu_list(list)
     fu_output_message sprintf('chmod %s %s', mode_to_s(mode), list.join(' ')) if verbose
@@ -1019,12 +1822,7 @@ module Bundler::FileUtils
   end
   module_function :chmod
 
-  #
-  # Changes permission bits on the named files (in +list+)
-  # to the bit pattern represented by +mode+.
-  #
-  #   Bundler::FileUtils.chmod_R 0700, "/tmp/app.#{$$}"
-  #   Bundler::FileUtils.chmod_R "u=wrx", "/tmp/app.#{$$}"
+  # Like Bundler::FileUtils.chmod, but changes permissions recursively.
   #
   def chmod_R(mode, list, noop: nil, verbose: nil, force: nil)
     list = fu_list(list)
@@ -1044,15 +1842,68 @@ module Bundler::FileUtils
   end
   module_function :chmod_R
 
+  # Changes the owner and group on the entries at the paths given in +list+
+  # (a single path or an array of paths)
+  # to the given +user+ and +group+;
+  # returns +list+ if it is an array, <tt>[list]</tt> otherwise:
+  #
+  # - Modifies each entry that is a regular file using
+  #   {File.chown}[rdoc-ref:File.chown].
+  # - Modifies each entry that is a symbolic link using
+  #   {File.lchown}[rdoc-ref:File.lchown].
+  #
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
   #
-  # Changes owner and group on the named files (in +list+)
-  # to the user +user+ and the group +group+.  +user+ and +group+
-  # may be an ID (Integer/String) or a name (String).
-  # If +user+ or +group+ is nil, this method does not change
-  # the attribute.
+  # User and group:
   #
-  #   Bundler::FileUtils.chown 'root', 'staff', '/usr/local/bin/ruby'
-  #   Bundler::FileUtils.chown nil, 'bin', Dir.glob('/usr/bin/*'), verbose: true
+  # - Argument +user+ may be a user name or a user id;
+  #   if +nil+ or +-1+, the user is not changed.
+  # - Argument +group+ may be a group name or a group id;
+  #   if +nil+ or +-1+, the group is not changed.
+  # - The user must be a member of the group.
+  #
+  # Examples:
+  #
+  #   # One path.
+  #   # User and group as string names.
+  #   File.stat('src0.txt').uid # => 1004
+  #   File.stat('src0.txt').gid # => 1004
+  #   Bundler::FileUtils.chown('user2', 'group1', 'src0.txt')
+  #   File.stat('src0.txt').uid # => 1006
+  #   File.stat('src0.txt').gid # => 1005
+  #
+  #   # User and group as uid and gid.
+  #   Bundler::FileUtils.chown(1004, 1004, 'src0.txt')
+  #   File.stat('src0.txt').uid # => 1004
+  #   File.stat('src0.txt').gid # => 1004
+  #
+  #   # Array of paths.
+  #   Bundler::FileUtils.chown(1006, 1005, ['src0.txt', 'src0.dat'])
+  #
+  #   # Directory (not recursive).
+  #   Bundler::FileUtils.chown('user2', 'group1', '.')
+  #
+  # Keyword arguments:
+  #
+  # - <tt>noop: true</tt> - does not change permissions; returns +nil+.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     Bundler::FileUtils.chown('user2', 'group1', 'src0.txt', noop: true, verbose: true)
+  #     Bundler::FileUtils.chown(1004, 1004, 'src0.txt', noop: true, verbose: true)
+  #     Bundler::FileUtils.chown(1006, 1005, ['src0.txt', 'src0.dat'], noop: true, verbose: true)
+  #     Bundler::FileUtils.chown('user2', 'group1', path, noop: true, verbose: true)
+  #     Bundler::FileUtils.chown('user2', 'group1', '.', noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     chown user2:group1 src0.txt
+  #     chown 1004:1004 src0.txt
+  #     chown 1006:1005 src0.txt src0.dat
+  #     chown user2:group1 src0.txt
+  #     chown user2:group1 .
+  #
+  # Related: Bundler::FileUtils.chown_R.
   #
   def chown(user, group, list, noop: nil, verbose: nil)
     list = fu_list(list)
@@ -1068,15 +1919,7 @@ module Bundler::FileUtils
   end
   module_function :chown
 
-  #
-  # Changes owner and group on the named files (in +list+)
-  # to the user +user+ and the group +group+ recursively.
-  # +user+ and +group+ may be an ID (Integer/String) or
-  # a name (String).  If +user+ or +group+ is nil, this
-  # method does not change the attribute.
-  #
-  #   Bundler::FileUtils.chown_R 'www', 'www', '/var/www/htdocs'
-  #   Bundler::FileUtils.chown_R 'cvs', 'cvs', '/var/cvs', verbose: true
+  # Like Bundler::FileUtils.chown, but changes owner and group recursively.
   #
   def chown_R(user, group, list, noop: nil, verbose: nil, force: nil)
     list = fu_list(list)
@@ -1127,12 +1970,50 @@ module Bundler::FileUtils
   end
   private_module_function :fu_get_gid
 
+  # Updates modification times (mtime) and access times (atime)
+  # of the entries given by the paths in +list+
+  # (a single path or an array of paths);
+  # returns +list+ if it is an array, <tt>[list]</tt> otherwise.
+  #
+  # By default, creates an empty file for any path to a non-existent entry;
+  # use keyword argument +nocreate+ to raise an exception instead.
+  #
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # Examples:
+  #
+  #   # Single path.
+  #   f = File.new('src0.txt') # Existing file.
+  #   f.atime # => 2022-06-10 11:11:21.200277 -0700
+  #   f.mtime # => 2022-06-10 11:11:21.200277 -0700
+  #   Bundler::FileUtils.touch('src0.txt')
+  #   f = File.new('src0.txt')
+  #   f.atime # => 2022-06-11 08:28:09.8185343 -0700
+  #   f.mtime # => 2022-06-11 08:28:09.8185343 -0700
   #
-  # Updates modification time (mtime) and access time (atime) of file(s) in
-  # +list+.  Files are created if they don't exist.
+  #   # Array of paths.
+  #   Bundler::FileUtils.touch(['src0.txt', 'src0.dat'])
   #
-  #   Bundler::FileUtils.touch 'timestamp'
-  #   Bundler::FileUtils.touch Dir.glob('*.c');  system 'make'
+  # Keyword arguments:
+  #
+  # - <tt>mtime: <i>time</i></tt> - sets the entry's mtime to the given time,
+  #   instead of the current time.
+  # - <tt>nocreate: true</tt> - raises an exception if the entry does not exist.
+  # - <tt>noop: true</tt> - does not touch entries; returns +nil+.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     Bundler::FileUtils.touch('src0.txt', noop: true, verbose: true)
+  #     Bundler::FileUtils.touch(['src0.txt', 'src0.dat'], noop: true, verbose: true)
+  #     Bundler::FileUtils.touch(path, noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     touch src0.txt
+  #     touch src0.txt src0.dat
+  #     touch src0.txt
+  #
+  # Related: Bundler::FileUtils.uptodate?.
   #
   def touch(list, noop: nil, verbose: nil, mtime: nil, nocreate: nil)
     list = fu_list(list)
@@ -1290,14 +2171,9 @@ module Bundler::FileUtils
 
     def entries
       opts = {}
-      opts[:encoding] = ::Encoding::UTF_8 if fu_windows?
+      opts[:encoding] = fu_windows? ? ::Encoding::UTF_8 : path.encoding
 
-      files = if Dir.respond_to?(:children)
-        Dir.children(path, **opts)
-      else
-        Dir.entries(path(), **opts)
-           .reject {|n| n == '.' or n == '..' }
-      end
+      files = Dir.children(path, **opts)
 
       untaint = RUBY_VERSION < '2.7'
       files.map {|n| Entry_.new(prefix(), join(rel(), untaint ? n.untaint : n)) }
@@ -1345,6 +2221,7 @@ module Bundler::FileUtils
       else
         File.chmod mode, path()
       end
+    rescue Errno::EOPNOTSUPP
     end
 
     def chown(uid, gid)
@@ -1439,7 +2316,7 @@ module Bundler::FileUtils
       if st.symlink?
         begin
           File.lchmod mode, path
-        rescue NotImplementedError
+        rescue NotImplementedError, Errno::EOPNOTSUPP
         end
       else
         File.chmod mode, path
@@ -1498,13 +2375,21 @@ module Bundler::FileUtils
 
     def postorder_traverse
       if directory?
-        entries().each do |ent|
+        begin
+          children = entries()
+        rescue Errno::EACCES
+          # Failed to get the list of children.
+          # Assuming there is no children, try to process the parent directory.
+          yield self
+          return
+        end
+
+        children.each do |ent|
           ent.postorder_traverse do |e|
             yield e
           end
         end
       end
-    ensure
       yield self
     end
 
@@ -1559,7 +2444,15 @@ module Bundler::FileUtils
     def join(dir, base)
       return File.path(dir) if not base or base == '.'
       return File.path(base) if not dir or dir == '.'
-      File.join(dir, base)
+      begin
+        File.join(dir, base)
+      rescue EncodingError
+        if fu_windows?
+          File.join(dir.encode(::Encoding::UTF_8), base.encode(::Encoding::UTF_8))
+        else
+          raise
+        end
+      end
     end
 
     if File::ALT_SEPARATOR
@@ -1590,15 +2483,15 @@ module Bundler::FileUtils
   end
   private_module_function :fu_each_src_dest
 
-  def fu_each_src_dest0(src, dest)   #:nodoc:
+  def fu_each_src_dest0(src, dest, target_directory = true)   #:nodoc:
     if tmp = Array.try_convert(src)
       tmp.each do |s|
         s = File.path(s)
-        yield s, File.join(dest, File.basename(s))
+        yield s, (target_directory ? File.join(dest, File.basename(s)) : dest)
       end
     else
       src = File.path(src)
-      if File.directory?(dest)
+      if target_directory and File.directory?(dest)
         yield src, File.join(dest, File.basename(src))
       else
         yield src, File.path(dest)
@@ -1614,7 +2507,7 @@ module Bundler::FileUtils
 
   def fu_output_message(msg)   #:nodoc:
     output = @fileutils_output if defined?(@fileutils_output)
-    output ||= $stderr
+    output ||= $stdout
     if defined?(@fileutils_label)
       msg = @fileutils_label + msg
     end
@@ -1622,6 +2515,56 @@ module Bundler::FileUtils
   end
   private_module_function :fu_output_message
 
+  def fu_split_path(path)
+    path = File.path(path)
+    list = []
+    until (parent, base = File.split(path); parent == path or parent == ".")
+      list << base
+      path = parent
+    end
+    list << path
+    list.reverse!
+  end
+  private_module_function :fu_split_path
+
+  def fu_relative_components_from(target, base) #:nodoc:
+    i = 0
+    while target[i]&.== base[i]
+      i += 1
+    end
+    Array.new(base.size-i, '..').concat(target[i..-1])
+  end
+  private_module_function :fu_relative_components_from
+
+  def fu_clean_components(*comp)
+    comp.shift while comp.first == "."
+    return comp if comp.empty?
+    clean = [comp.shift]
+    path = File.join(*clean, "") # ending with File::SEPARATOR
+    while c = comp.shift
+      if c == ".." and clean.last != ".." and !(fu_have_symlink? && File.symlink?(path))
+        clean.pop
+        path.chomp!(%r((?<=\A|/)[^/]+/\z), "")
+      else
+        clean << c
+        path << c << "/"
+      end
+    end
+    clean
+  end
+  private_module_function :fu_clean_components
+
+  if fu_windows?
+    def fu_starting_path?(path)
+      path&.start_with?(%r(\w:|/))
+    end
+  else
+    def fu_starting_path?(path)
+      path&.start_with?("/")
+    end
+  end
+  private_module_function :fu_starting_path?
+
   # This hash table holds command options.
   OPT_TABLE = {}    #:nodoc: internal use only
   (private_instance_methods & methods(false)).inject(OPT_TABLE) {|tbl, name|
@@ -1631,50 +2574,49 @@ module Bundler::FileUtils
 
   public
 
+  # Returns an array of the string names of \Bundler::FileUtils methods
+  # that accept one or more keyword arguments:
   #
-  # Returns an Array of names of high-level methods that accept any keyword
-  # arguments.
-  #
-  #   p Bundler::FileUtils.commands  #=> ["chmod", "cp", "cp_r", "install", ...]
+  #   Bundler::FileUtils.commands.sort.take(3) # => ["cd", "chdir", "chmod"]
   #
   def self.commands
     OPT_TABLE.keys
   end
 
+  # Returns an array of the string keyword names:
   #
-  # Returns an Array of option names.
-  #
-  #   p Bundler::FileUtils.options  #=> ["noop", "force", "verbose", "preserve", "mode"]
+  #   Bundler::FileUtils.options.take(3) # => ["noop", "verbose", "force"]
   #
   def self.options
     OPT_TABLE.values.flatten.uniq.map {|sym| sym.to_s }
   end
 
+  # Returns +true+ if method +mid+ accepts the given option +opt+, +false+ otherwise;
+  # the arguments may be strings or symbols:
   #
-  # Returns true if the method +mid+ have an option +opt+.
-  #
-  #   p Bundler::FileUtils.have_option?(:cp, :noop)     #=> true
-  #   p Bundler::FileUtils.have_option?(:rm, :force)    #=> true
-  #   p Bundler::FileUtils.have_option?(:rm, :preserve) #=> false
+  #   Bundler::FileUtils.have_option?(:chmod, :noop) # => true
+  #   Bundler::FileUtils.have_option?('chmod', 'secure') # => false
   #
   def self.have_option?(mid, opt)
     li = OPT_TABLE[mid.to_s] or raise ArgumentError, "no such method: #{mid}"
     li.include?(opt)
   end
 
+  # Returns an array of the string keyword name for method +mid+;
+  # the argument may be a string or a symbol:
   #
-  # Returns an Array of option names of the method +mid+.
-  #
-  #   p Bundler::FileUtils.options_of(:rm)  #=> ["noop", "verbose", "force"]
+  #   Bundler::FileUtils.options_of(:rm) # => ["force", "noop", "verbose"]
+  #   Bundler::FileUtils.options_of('mv') # => ["force", "noop", "verbose", "secure"]
   #
   def self.options_of(mid)
     OPT_TABLE[mid.to_s].map {|sym| sym.to_s }
   end
 
+  # Returns an array of the string method names of the methods
+  # that accept the given keyword option +opt+;
+  # the argument must be a symbol:
   #
-  # Returns an Array of methods names which have the option +opt+.
-  #
-  #   p Bundler::FileUtils.collect_method(:preserve) #=> ["cp", "cp_r", "copy", "install"]
+  #   Bundler::FileUtils.collect_method(:preserve) # => ["cp", "copy", "cp_r", "install"]
   #
   def self.collect_method(opt)
     OPT_TABLE.keys.select {|m| OPT_TABLE[m].include?(opt) }
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo.rb b/lib/bundler/vendor/molinillo/lib/molinillo.rb
deleted file mode 100644
index a52b96deaf..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo.rb
+++ /dev/null
@@ -1,11 +0,0 @@
-# frozen_string_literal: true
-
-require_relative 'molinillo/gem_metadata'
-require_relative 'molinillo/errors'
-require_relative 'molinillo/resolver'
-require_relative 'molinillo/modules/ui'
-require_relative 'molinillo/modules/specification_provider'
-
-# Bundler::Molinillo is a generic dependency resolution algorithm.
-module Bundler::Molinillo
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/delegates/resolution_state.rb b/lib/bundler/vendor/molinillo/lib/molinillo/delegates/resolution_state.rb
deleted file mode 100644
index bcacf35243..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/delegates/resolution_state.rb
+++ /dev/null
@@ -1,57 +0,0 @@
-# frozen_string_literal: true
-
-module Bundler::Molinillo
-  # @!visibility private
-  module Delegates
-    # Delegates all {Bundler::Molinillo::ResolutionState} methods to a `#state` property.
-    module ResolutionState
-      # (see Bundler::Molinillo::ResolutionState#name)
-      def name
-        current_state = state || Bundler::Molinillo::ResolutionState.empty
-        current_state.name
-      end
-
-      # (see Bundler::Molinillo::ResolutionState#requirements)
-      def requirements
-        current_state = state || Bundler::Molinillo::ResolutionState.empty
-        current_state.requirements
-      end
-
-      # (see Bundler::Molinillo::ResolutionState#activated)
-      def activated
-        current_state = state || Bundler::Molinillo::ResolutionState.empty
-        current_state.activated
-      end
-
-      # (see Bundler::Molinillo::ResolutionState#requirement)
-      def requirement
-        current_state = state || Bundler::Molinillo::ResolutionState.empty
-        current_state.requirement
-      end
-
-      # (see Bundler::Molinillo::ResolutionState#possibilities)
-      def possibilities
-        current_state = state || Bundler::Molinillo::ResolutionState.empty
-        current_state.possibilities
-      end
-
-      # (see Bundler::Molinillo::ResolutionState#depth)
-      def depth
-        current_state = state || Bundler::Molinillo::ResolutionState.empty
-        current_state.depth
-      end
-
-      # (see Bundler::Molinillo::ResolutionState#conflicts)
-      def conflicts
-        current_state = state || Bundler::Molinillo::ResolutionState.empty
-        current_state.conflicts
-      end
-
-      # (see Bundler::Molinillo::ResolutionState#unused_unwind_options)
-      def unused_unwind_options
-        current_state = state || Bundler::Molinillo::ResolutionState.empty
-        current_state.unused_unwind_options
-      end
-    end
-  end
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/delegates/specification_provider.rb b/lib/bundler/vendor/molinillo/lib/molinillo/delegates/specification_provider.rb
deleted file mode 100644
index f8c695c1ed..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/delegates/specification_provider.rb
+++ /dev/null
@@ -1,88 +0,0 @@
-# frozen_string_literal: true
-
-module Bundler::Molinillo
-  module Delegates
-    # Delegates all {Bundler::Molinillo::SpecificationProvider} methods to a
-    # `#specification_provider` property.
-    module SpecificationProvider
-      # (see Bundler::Molinillo::SpecificationProvider#search_for)
-      def search_for(dependency)
-        with_no_such_dependency_error_handling do
-          specification_provider.search_for(dependency)
-        end
-      end
-
-      # (see Bundler::Molinillo::SpecificationProvider#dependencies_for)
-      def dependencies_for(specification)
-        with_no_such_dependency_error_handling do
-          specification_provider.dependencies_for(specification)
-        end
-      end
-
-      # (see Bundler::Molinillo::SpecificationProvider#requirement_satisfied_by?)
-      def requirement_satisfied_by?(requirement, activated, spec)
-        with_no_such_dependency_error_handling do
-          specification_provider.requirement_satisfied_by?(requirement, activated, spec)
-        end
-      end
-
-      # (see Bundler::Molinillo::SpecificationProvider#dependencies_equal?)
-      def dependencies_equal?(dependencies, other_dependencies)
-        with_no_such_dependency_error_handling do
-          specification_provider.dependencies_equal?(dependencies, other_dependencies)
-        end
-      end
-
-      # (see Bundler::Molinillo::SpecificationProvider#name_for)
-      def name_for(dependency)
-        with_no_such_dependency_error_handling do
-          specification_provider.name_for(dependency)
-        end
-      end
-
-      # (see Bundler::Molinillo::SpecificationProvider#name_for_explicit_dependency_source)
-      def name_for_explicit_dependency_source
-        with_no_such_dependency_error_handling do
-          specification_provider.name_for_explicit_dependency_source
-        end
-      end
-
-      # (see Bundler::Molinillo::SpecificationProvider#name_for_locking_dependency_source)
-      def name_for_locking_dependency_source
-        with_no_such_dependency_error_handling do
-          specification_provider.name_for_locking_dependency_source
-        end
-      end
-
-      # (see Bundler::Molinillo::SpecificationProvider#sort_dependencies)
-      def sort_dependencies(dependencies, activated, conflicts)
-        with_no_such_dependency_error_handling do
-          specification_provider.sort_dependencies(dependencies, activated, conflicts)
-        end
-      end
-
-      # (see Bundler::Molinillo::SpecificationProvider#allow_missing?)
-      def allow_missing?(dependency)
-        with_no_such_dependency_error_handling do
-          specification_provider.allow_missing?(dependency)
-        end
-      end
-
-      private
-
-      # Ensures any raised {NoSuchDependencyError} has its
-      # {NoSuchDependencyError#required_by} set.
-      # @yield
-      def with_no_such_dependency_error_handling
-        yield
-      rescue NoSuchDependencyError => error
-        if state
-          vertex = activated.vertex_named(name_for(error.dependency))
-          error.required_by += vertex.incoming_edges.map { |e| e.origin.name }
-          error.required_by << name_for_explicit_dependency_source unless vertex.explicit_requirements.empty?
-        end
-        raise
-      end
-    end
-  end
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph.rb b/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph.rb
deleted file mode 100644
index 10a25d2f08..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph.rb
+++ /dev/null
@@ -1,255 +0,0 @@
-# frozen_string_literal: true
-
-require_relative '../../../../vendored_tsort'
-
-require_relative 'dependency_graph/log'
-require_relative 'dependency_graph/vertex'
-
-module Bundler::Molinillo
-  # A directed acyclic graph that is tuned to hold named dependencies
-  class DependencyGraph
-    include Enumerable
-
-    # Enumerates through the vertices of the graph.
-    # @return [Array<Vertex>] The graph's vertices.
-    def each
-      return vertices.values.each unless block_given?
-      vertices.values.each { |v| yield v }
-    end
-
-    include Bundler::TSort
-
-    # @!visibility private
-    alias tsort_each_node each
-
-    # @!visibility private
-    def tsort_each_child(vertex, &block)
-      vertex.successors.each(&block)
-    end
-
-    # Topologically sorts the given vertices.
-    # @param [Enumerable<Vertex>] vertices the vertices to be sorted, which must
-    #   all belong to the same graph.
-    # @return [Array<Vertex>] The sorted vertices.
-    def self.tsort(vertices)
-      TSort.tsort(
-        lambda { |b| vertices.each(&b) },
-        lambda { |v, &b| (v.successors & vertices).each(&b) }
-      )
-    end
-
-    # A directed edge of a {DependencyGraph}
-    # @attr [Vertex] origin The origin of the directed edge
-    # @attr [Vertex] destination The destination of the directed edge
-    # @attr [Object] requirement The requirement the directed edge represents
-    Edge = Struct.new(:origin, :destination, :requirement)
-
-    # @return [{String => Vertex}] the vertices of the dependency graph, keyed
-    #   by {Vertex#name}
-    attr_reader :vertices
-
-    # @return [Log] the op log for this graph
-    attr_reader :log
-
-    # Initializes an empty dependency graph
-    def initialize
-      @vertices = {}
-      @log = Log.new
-    end
-
-    # Tags the current state of the dependency as the given tag
-    # @param  [Object] tag an opaque tag for the current state of the graph
-    # @return [Void]
-    def tag(tag)
-      log.tag(self, tag)
-    end
-
-    # Rewinds the graph to the state tagged as `tag`
-    # @param  [Object] tag the tag to rewind to
-    # @return [Void]
-    def rewind_to(tag)
-      log.rewind_to(self, tag)
-    end
-
-    # Initializes a copy of a {DependencyGraph}, ensuring that all {#vertices}
-    # are properly copied.
-    # @param [DependencyGraph] other the graph to copy.
-    def initialize_copy(other)
-      super
-      @vertices = {}
-      @log = other.log.dup
-      traverse = lambda do |new_v, old_v|
-        return if new_v.outgoing_edges.size == old_v.outgoing_edges.size
-        old_v.outgoing_edges.each do |edge|
-          destination = add_vertex(edge.destination.name, edge.destination.payload)
-          add_edge_no_circular(new_v, destination, edge.requirement)
-          traverse.call(destination, edge.destination)
-        end
-      end
-      other.vertices.each do |name, vertex|
-        new_vertex = add_vertex(name, vertex.payload, vertex.root?)
-        new_vertex.explicit_requirements.replace(vertex.explicit_requirements)
-        traverse.call(new_vertex, vertex)
-      end
-    end
-
-    # @return [String] a string suitable for debugging
-    def inspect
-      "#{self.class}:#{vertices.values.inspect}"
-    end
-
-    # @param [Hash] options options for dot output.
-    # @return [String] Returns a dot format representation of the graph
-    def to_dot(options = {})
-      edge_label = options.delete(:edge_label)
-      raise ArgumentError, "Unknown options: #{options.keys}" unless options.empty?
-
-      dot_vertices = []
-      dot_edges = []
-      vertices.each do |n, v|
-        dot_vertices << "  #{n} [label=\"{#{n}|#{v.payload}}\"]"
-        v.outgoing_edges.each do |e|
-          label = edge_label ? edge_label.call(e) : e.requirement
-          dot_edges << "  #{e.origin.name} -> #{e.destination.name} [label=#{label.to_s.dump}]"
-        end
-      end
-
-      dot_vertices.uniq!
-      dot_vertices.sort!
-      dot_edges.uniq!
-      dot_edges.sort!
-
-      dot = dot_vertices.unshift('digraph G {').push('') + dot_edges.push('}')
-      dot.join("\n")
-    end
-
-    # @param [DependencyGraph] other
-    # @return [Boolean] whether the two dependency graphs are equal, determined
-    #   by a recursive traversal of each {#root_vertices} and its
-    #   {Vertex#successors}
-    def ==(other)
-      return false unless other
-      return true if equal?(other)
-      vertices.each do |name, vertex|
-        other_vertex = other.vertex_named(name)
-        return false unless other_vertex
-        return false unless vertex.payload == other_vertex.payload
-        return false unless other_vertex.successors.to_set == vertex.successors.to_set
-      end
-    end
-
-    # @param [String] name
-    # @param [Object] payload
-    # @param [Array<String>] parent_names
-    # @param [Object] requirement the requirement that is requiring the child
-    # @return [void]
-    def add_child_vertex(name, payload, parent_names, requirement)
-      root = !parent_names.delete(nil) { true }
-      vertex = add_vertex(name, payload, root)
-      vertex.explicit_requirements << requirement if root
-      parent_names.each do |parent_name|
-        parent_vertex = vertex_named(parent_name)
-        add_edge(parent_vertex, vertex, requirement)
-      end
-      vertex
-    end
-
-    # Adds a vertex with the given name, or updates the existing one.
-    # @param [String] name
-    # @param [Object] payload
-    # @return [Vertex] the vertex that was added to `self`
-    def add_vertex(name, payload, root = false)
-      log.add_vertex(self, name, payload, root)
-    end
-
-    # Detaches the {#vertex_named} `name` {Vertex} from the graph, recursively
-    # removing any non-root vertices that were orphaned in the process
-    # @param [String] name
-    # @return [Array<Vertex>] the vertices which have been detached
-    def detach_vertex_named(name)
-      log.detach_vertex_named(self, name)
-    end
-
-    # @param [String] name
-    # @return [Vertex,nil] the vertex with the given name
-    def vertex_named(name)
-      vertices[name]
-    end
-
-    # @param [String] name
-    # @return [Vertex,nil] the root vertex with the given name
-    def root_vertex_named(name)
-      vertex = vertex_named(name)
-      vertex if vertex && vertex.root?
-    end
-
-    # Adds a new {Edge} to the dependency graph
-    # @param [Vertex] origin
-    # @param [Vertex] destination
-    # @param [Object] requirement the requirement that this edge represents
-    # @return [Edge] the added edge
-    def add_edge(origin, destination, requirement)
-      if destination.path_to?(origin)
-        raise CircularDependencyError.new(path(destination, origin))
-      end
-      add_edge_no_circular(origin, destination, requirement)
-    end
-
-    # Deletes an {Edge} from the dependency graph
-    # @param [Edge] edge
-    # @return [Void]
-    def delete_edge(edge)
-      log.delete_edge(self, edge.origin.name, edge.destination.name, edge.requirement)
-    end
-
-    # Sets the payload of the vertex with the given name
-    # @param [String] name the name of the vertex
-    # @param [Object] payload the payload
-    # @return [Void]
-    def set_payload(name, payload)
-      log.set_payload(self, name, payload)
-    end
-
-    private
-
-    # Adds a new {Edge} to the dependency graph without checking for
-    # circularity.
-    # @param (see #add_edge)
-    # @return (see #add_edge)
-    def add_edge_no_circular(origin, destination, requirement)
-      log.add_edge_no_circular(self, origin.name, destination.name, requirement)
-    end
-
-    # Returns the path between two vertices
-    # @raise [ArgumentError] if there is no path between the vertices
-    # @param [Vertex] from
-    # @param [Vertex] to
-    # @return [Array<Vertex>] the shortest path from `from` to `to`
-    def path(from, to)
-      distances = Hash.new(vertices.size + 1)
-      distances[from.name] = 0
-      predecessors = {}
-      each do |vertex|
-        vertex.successors.each do |successor|
-          if distances[successor.name] > distances[vertex.name] + 1
-            distances[successor.name] = distances[vertex.name] + 1
-            predecessors[successor] = vertex
-          end
-        end
-      end
-
-      path = [to]
-      while before = predecessors[to]
-        path << before
-        to = before
-        break if to == from
-      end
-
-      unless path.last.equal?(from)
-        raise ArgumentError, "There is no path from #{from.name} to #{to.name}"
-      end
-
-      path.reverse
-    end
-  end
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/action.rb b/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/action.rb
deleted file mode 100644
index c04c7eec9c..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/action.rb
+++ /dev/null
@@ -1,36 +0,0 @@
-# frozen_string_literal: true
-
-module Bundler::Molinillo
-  class DependencyGraph
-    # An action that modifies a {DependencyGraph} that is reversible.
-    # @abstract
-    class Action
-      # rubocop:disable Lint/UnusedMethodArgument
-
-      # @return [Symbol] The name of the action.
-      def self.action_name
-        raise 'Abstract'
-      end
-
-      # Performs the action on the given graph.
-      # @param  [DependencyGraph] graph the graph to perform the action on.
-      # @return [Void]
-      def up(graph)
-        raise 'Abstract'
-      end
-
-      # Reverses the action on the given graph.
-      # @param  [DependencyGraph] graph the graph to reverse the action on.
-      # @return [Void]
-      def down(graph)
-        raise 'Abstract'
-      end
-
-      # @return [Action,Nil] The previous action
-      attr_accessor :previous
-
-      # @return [Action,Nil] The next action
-      attr_accessor :next
-    end
-  end
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/add_edge_no_circular.rb b/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/add_edge_no_circular.rb
deleted file mode 100644
index 946a08236e..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/add_edge_no_circular.rb
+++ /dev/null
@@ -1,66 +0,0 @@
-# frozen_string_literal: true
-
-require_relative 'action'
-module Bundler::Molinillo
-  class DependencyGraph
-    # @!visibility private
-    # (see DependencyGraph#add_edge_no_circular)
-    class AddEdgeNoCircular < Action
-      # @!group Action
-
-      # (see Action.action_name)
-      def self.action_name
-        :add_vertex
-      end
-
-      # (see Action#up)
-      def up(graph)
-        edge = make_edge(graph)
-        edge.origin.outgoing_edges << edge
-        edge.destination.incoming_edges << edge
-        edge
-      end
-
-      # (see Action#down)
-      def down(graph)
-        edge = make_edge(graph)
-        delete_first(edge.origin.outgoing_edges, edge)
-        delete_first(edge.destination.incoming_edges, edge)
-      end
-
-      # @!group AddEdgeNoCircular
-
-      # @return [String] the name of the origin of the edge
-      attr_reader :origin
-
-      # @return [String] the name of the destination of the edge
-      attr_reader :destination
-
-      # @return [Object] the requirement that the edge represents
-      attr_reader :requirement
-
-      # @param  [DependencyGraph] graph the graph to find vertices from
-      # @return [Edge] The edge this action adds
-      def make_edge(graph)
-        Edge.new(graph.vertex_named(origin), graph.vertex_named(destination), requirement)
-      end
-
-      # Initialize an action to add an edge to a dependency graph
-      # @param [String] origin the name of the origin of the edge
-      # @param [String] destination the name of the destination of the edge
-      # @param [Object] requirement the requirement that the edge represents
-      def initialize(origin, destination, requirement)
-        @origin = origin
-        @destination = destination
-        @requirement = requirement
-      end
-
-      private
-
-      def delete_first(array, item)
-        return unless index = array.index(item)
-        array.delete_at(index)
-      end
-    end
-  end
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/add_vertex.rb b/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/add_vertex.rb
deleted file mode 100644
index 483527daf8..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/add_vertex.rb
+++ /dev/null
@@ -1,62 +0,0 @@
-# frozen_string_literal: true
-
-require_relative 'action'
-module Bundler::Molinillo
-  class DependencyGraph
-    # @!visibility private
-    # (see DependencyGraph#add_vertex)
-    class AddVertex < Action # :nodoc:
-      # @!group Action
-
-      # (see Action.action_name)
-      def self.action_name
-        :add_vertex
-      end
-
-      # (see Action#up)
-      def up(graph)
-        if existing = graph.vertices[name]
-          @existing_payload = existing.payload
-          @existing_root = existing.root
-        end
-        vertex = existing || Vertex.new(name, payload)
-        graph.vertices[vertex.name] = vertex
-        vertex.payload ||= payload
-        vertex.root ||= root
-        vertex
-      end
-
-      # (see Action#down)
-      def down(graph)
-        if defined?(@existing_payload)
-          vertex = graph.vertices[name]
-          vertex.payload = @existing_payload
-          vertex.root = @existing_root
-        else
-          graph.vertices.delete(name)
-        end
-      end
-
-      # @!group AddVertex
-
-      # @return [String] the name of the vertex
-      attr_reader :name
-
-      # @return [Object] the payload for the vertex
-      attr_reader :payload
-
-      # @return [Boolean] whether the vertex is root or not
-      attr_reader :root
-
-      # Initialize an action to add a vertex to a dependency graph
-      # @param [String] name the name of the vertex
-      # @param [Object] payload the payload for the vertex
-      # @param [Boolean] root whether the vertex is root or not
-      def initialize(name, payload, root)
-        @name = name
-        @payload = payload
-        @root = root
-      end
-    end
-  end
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/delete_edge.rb b/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/delete_edge.rb
deleted file mode 100644
index d81940585a..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/delete_edge.rb
+++ /dev/null
@@ -1,63 +0,0 @@
-# frozen_string_literal: true
-
-require_relative 'action'
-module Bundler::Molinillo
-  class DependencyGraph
-    # @!visibility private
-    # (see DependencyGraph#delete_edge)
-    class DeleteEdge < Action
-      # @!group Action
-
-      # (see Action.action_name)
-      def self.action_name
-        :delete_edge
-      end
-
-      # (see Action#up)
-      def up(graph)
-        edge = make_edge(graph)
-        edge.origin.outgoing_edges.delete(edge)
-        edge.destination.incoming_edges.delete(edge)
-      end
-
-      # (see Action#down)
-      def down(graph)
-        edge = make_edge(graph)
-        edge.origin.outgoing_edges << edge
-        edge.destination.incoming_edges << edge
-        edge
-      end
-
-      # @!group DeleteEdge
-
-      # @return [String] the name of the origin of the edge
-      attr_reader :origin_name
-
-      # @return [String] the name of the destination of the edge
-      attr_reader :destination_name
-
-      # @return [Object] the requirement that the edge represents
-      attr_reader :requirement
-
-      # @param  [DependencyGraph] graph the graph to find vertices from
-      # @return [Edge] The edge this action adds
-      def make_edge(graph)
-        Edge.new(
-          graph.vertex_named(origin_name),
-          graph.vertex_named(destination_name),
-          requirement
-        )
-      end
-
-      # Initialize an action to add an edge to a dependency graph
-      # @param [String] origin_name the name of the origin of the edge
-      # @param [String] destination_name the name of the destination of the edge
-      # @param [Object] requirement the requirement that the edge represents
-      def initialize(origin_name, destination_name, requirement)
-        @origin_name = origin_name
-        @destination_name = destination_name
-        @requirement = requirement
-      end
-    end
-  end
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/detach_vertex_named.rb b/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/detach_vertex_named.rb
deleted file mode 100644
index 36fce7c526..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/detach_vertex_named.rb
+++ /dev/null
@@ -1,61 +0,0 @@
-# frozen_string_literal: true
-
-require_relative 'action'
-module Bundler::Molinillo
-  class DependencyGraph
-    # @!visibility private
-    # @see DependencyGraph#detach_vertex_named
-    class DetachVertexNamed < Action
-      # @!group Action
-
-      # (see Action#name)
-      def self.action_name
-        :add_vertex
-      end
-
-      # (see Action#up)
-      def up(graph)
-        return [] unless @vertex = graph.vertices.delete(name)
-
-        removed_vertices = [@vertex]
-        @vertex.outgoing_edges.each do |e|
-          v = e.destination
-          v.incoming_edges.delete(e)
-          if !v.root? && v.incoming_edges.empty?
-            removed_vertices.concat graph.detach_vertex_named(v.name)
-          end
-        end
-
-        @vertex.incoming_edges.each do |e|
-          v = e.origin
-          v.outgoing_edges.delete(e)
-        end
-
-        removed_vertices
-      end
-
-      # (see Action#down)
-      def down(graph)
-        return unless @vertex
-        graph.vertices[@vertex.name] = @vertex
-        @vertex.outgoing_edges.each do |e|
-          e.destination.incoming_edges << e
-        end
-        @vertex.incoming_edges.each do |e|
-          e.origin.outgoing_edges << e
-        end
-      end
-
-      # @!group DetachVertexNamed
-
-      # @return [String] the name of the vertex to detach
-      attr_reader :name
-
-      # Initialize an action to detach a vertex from a dependency graph
-      # @param [String] name the name of the vertex to detach
-      def initialize(name)
-        @name = name
-      end
-    end
-  end
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/log.rb b/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/log.rb
deleted file mode 100644
index 6f0de19886..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/log.rb
+++ /dev/null
@@ -1,126 +0,0 @@
-# frozen_string_literal: true
-
-require_relative 'add_edge_no_circular'
-require_relative 'add_vertex'
-require_relative 'delete_edge'
-require_relative 'detach_vertex_named'
-require_relative 'set_payload'
-require_relative 'tag'
-
-module Bundler::Molinillo
-  class DependencyGraph
-    # A log for dependency graph actions
-    class Log
-      # Initializes an empty log
-      def initialize
-        @current_action = @first_action = nil
-      end
-
-      # @!macro [new] action
-      #   {include:DependencyGraph#$0}
-      #   @param [Graph] graph the graph to perform the action on
-      #   @param (see DependencyGraph#$0)
-      #   @return (see DependencyGraph#$0)
-
-      # @macro action
-      def tag(graph, tag)
-        push_action(graph, Tag.new(tag))
-      end
-
-      # @macro action
-      def add_vertex(graph, name, payload, root)
-        push_action(graph, AddVertex.new(name, payload, root))
-      end
-
-      # @macro action
-      def detach_vertex_named(graph, name)
-        push_action(graph, DetachVertexNamed.new(name))
-      end
-
-      # @macro action
-      def add_edge_no_circular(graph, origin, destination, requirement)
-        push_action(graph, AddEdgeNoCircular.new(origin, destination, requirement))
-      end
-
-      # {include:DependencyGraph#delete_edge}
-      # @param [Graph] graph the graph to perform the action on
-      # @param [String] origin_name
-      # @param [String] destination_name
-      # @param [Object] requirement
-      # @return (see DependencyGraph#delete_edge)
-      def delete_edge(graph, origin_name, destination_name, requirement)
-        push_action(graph, DeleteEdge.new(origin_name, destination_name, requirement))
-      end
-
-      # @macro action
-      def set_payload(graph, name, payload)
-        push_action(graph, SetPayload.new(name, payload))
-      end
-
-      # Pops the most recent action from the log and undoes the action
-      # @param [DependencyGraph] graph
-      # @return [Action] the action that was popped off the log
-      def pop!(graph)
-        return unless action = @current_action
-        unless @current_action = action.previous
-          @first_action = nil
-        end
-        action.down(graph)
-        action
-      end
-
-      extend Enumerable
-
-      # @!visibility private
-      # Enumerates each action in the log
-      # @yield [Action]
-      def each
-        return enum_for unless block_given?
-        action = @first_action
-        loop do
-          break unless action
-          yield action
-          action = action.next
-        end
-        self
-      end
-
-      # @!visibility private
-      # Enumerates each action in the log in reverse order
-      # @yield [Action]
-      def reverse_each
-        return enum_for(:reverse_each) unless block_given?
-        action = @current_action
-        loop do
-          break unless action
-          yield action
-          action = action.previous
-        end
-        self
-      end
-
-      # @macro action
-      def rewind_to(graph, tag)
-        loop do
-          action = pop!(graph)
-          raise "No tag #{tag.inspect} found" unless action
-          break if action.class.action_name == :tag && action.tag == tag
-        end
-      end
-
-      private
-
-      # Adds the given action to the log, running the action
-      # @param [DependencyGraph] graph
-      # @param [Action] action
-      # @return The value returned by `action.up`
-      def push_action(graph, action)
-        action.previous = @current_action
-        @current_action.next = action if @current_action
-        @current_action = action
-        @first_action ||= action
-        action.up(graph)
-      end
-    end
-  end
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/set_payload.rb b/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/set_payload.rb
deleted file mode 100644
index 2e9b90e6cd..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/set_payload.rb
+++ /dev/null
@@ -1,46 +0,0 @@
-# frozen_string_literal: true
-
-require_relative 'action'
-module Bundler::Molinillo
-  class DependencyGraph
-    # @!visibility private
-    # @see DependencyGraph#set_payload
-    class SetPayload < Action # :nodoc:
-      # @!group Action
-
-      # (see Action.action_name)
-      def self.action_name
-        :set_payload
-      end
-
-      # (see Action#up)
-      def up(graph)
-        vertex = graph.vertex_named(name)
-        @old_payload = vertex.payload
-        vertex.payload = payload
-      end
-
-      # (see Action#down)
-      def down(graph)
-        graph.vertex_named(name).payload = @old_payload
-      end
-
-      # @!group SetPayload
-
-      # @return [String] the name of the vertex
-      attr_reader :name
-
-      # @return [Object] the payload for the vertex
-      attr_reader :payload
-
-      # Initialize an action to add set the payload for a vertex in a dependency
-      # graph
-      # @param [String] name the name of the vertex
-      # @param [Object] payload the payload for the vertex
-      def initialize(name, payload)
-        @name = name
-        @payload = payload
-      end
-    end
-  end
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/tag.rb b/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/tag.rb
deleted file mode 100644
index 5b5da3e4f9..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/tag.rb
+++ /dev/null
@@ -1,36 +0,0 @@
-# frozen_string_literal: true
-
-require_relative 'action'
-module Bundler::Molinillo
-  class DependencyGraph
-    # @!visibility private
-    # @see DependencyGraph#tag
-    class Tag < Action
-      # @!group Action
-
-      # (see Action.action_name)
-      def self.action_name
-        :tag
-      end
-
-      # (see Action#up)
-      def up(graph)
-      end
-
-      # (see Action#down)
-      def down(graph)
-      end
-
-      # @!group Tag
-
-      # @return [Object] An opaque tag
-      attr_reader :tag
-
-      # Initialize an action to tag a state of a dependency graph
-      # @param [Object] tag an opaque tag
-      def initialize(tag)
-        @tag = tag
-      end
-    end
-  end
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/vertex.rb b/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/vertex.rb
deleted file mode 100644
index 1185a8ab05..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/vertex.rb
+++ /dev/null
@@ -1,164 +0,0 @@
-# frozen_string_literal: true
-
-module Bundler::Molinillo
-  class DependencyGraph
-    # A vertex in a {DependencyGraph} that encapsulates a {#name} and a
-    # {#payload}
-    class Vertex
-      # @return [String] the name of the vertex
-      attr_accessor :name
-
-      # @return [Object] the payload the vertex holds
-      attr_accessor :payload
-
-      # @return [Array<Object>] the explicit requirements that required
-      #   this vertex
-      attr_reader :explicit_requirements
-
-      # @return [Boolean] whether the vertex is considered a root vertex
-      attr_accessor :root
-      alias root? root
-
-      # Initializes a vertex with the given name and payload.
-      # @param [String] name see {#name}
-      # @param [Object] payload see {#payload}
-      def initialize(name, payload)
-        @name = name.frozen? ? name : name.dup.freeze
-        @payload = payload
-        @explicit_requirements = []
-        @outgoing_edges = []
-        @incoming_edges = []
-      end
-
-      # @return [Array<Object>] all of the requirements that required
-      #   this vertex
-      def requirements
-        (incoming_edges.map(&:requirement) + explicit_requirements).uniq
-      end
-
-      # @return [Array<Edge>] the edges of {#graph} that have `self` as their
-      #   {Edge#origin}
-      attr_accessor :outgoing_edges
-
-      # @return [Array<Edge>] the edges of {#graph} that have `self` as their
-      #   {Edge#destination}
-      attr_accessor :incoming_edges
-
-      # @return [Array<Vertex>] the vertices of {#graph} that have an edge with
-      #   `self` as their {Edge#destination}
-      def predecessors
-        incoming_edges.map(&:origin)
-      end
-
-      # @return [Set<Vertex>] the vertices of {#graph} where `self` is a
-      #   {#descendent?}
-      def recursive_predecessors
-        _recursive_predecessors
-      end
-
-      # @param [Set<Vertex>] vertices the set to add the predecessors to
-      # @return [Set<Vertex>] the vertices of {#graph} where `self` is a
-      #   {#descendent?}
-      def _recursive_predecessors(vertices = new_vertex_set)
-        incoming_edges.each do |edge|
-          vertex = edge.origin
-          next unless vertices.add?(vertex)
-          vertex._recursive_predecessors(vertices)
-        end
-
-        vertices
-      end
-      protected :_recursive_predecessors
-
-      # @return [Array<Vertex>] the vertices of {#graph} that have an edge with
-      #   `self` as their {Edge#origin}
-      def successors
-        outgoing_edges.map(&:destination)
-      end
-
-      # @return [Set<Vertex>] the vertices of {#graph} where `self` is an
-      #   {#ancestor?}
-      def recursive_successors
-        _recursive_successors
-      end
-
-      # @param [Set<Vertex>] vertices the set to add the successors to
-      # @return [Set<Vertex>] the vertices of {#graph} where `self` is an
-      #   {#ancestor?}
-      def _recursive_successors(vertices = new_vertex_set)
-        outgoing_edges.each do |edge|
-          vertex = edge.destination
-          next unless vertices.add?(vertex)
-          vertex._recursive_successors(vertices)
-        end
-
-        vertices
-      end
-      protected :_recursive_successors
-
-      # @return [String] a string suitable for debugging
-      def inspect
-        "#{self.class}:#{name}(#{payload.inspect})"
-      end
-
-      # @return [Boolean] whether the two vertices are equal, determined
-      #   by a recursive traversal of each {Vertex#successors}
-      def ==(other)
-        return true if equal?(other)
-        shallow_eql?(other) &&
-          successors.to_set == other.successors.to_set
-      end
-
-      # @param  [Vertex] other the other vertex to compare to
-      # @return [Boolean] whether the two vertices are equal, determined
-      #   solely by {#name} and {#payload} equality
-      def shallow_eql?(other)
-        return true if equal?(other)
-        other &&
-          name == other.name &&
-          payload == other.payload
-      end
-
-      alias eql? ==
-
-      # @return [Fixnum] a hash for the vertex based upon its {#name}
-      def hash
-        name.hash
-      end
-
-      # Is there a path from `self` to `other` following edges in the
-      # dependency graph?
-      # @return whether there is a path following edges within this {#graph}
-      def path_to?(other)
-        _path_to?(other)
-      end
-
-      alias descendent? path_to?
-
-      # @param [Vertex] other the vertex to check if there's a path to
-      # @param [Set<Vertex>] visited the vertices of {#graph} that have been visited
-      # @return [Boolean] whether there is a path to `other` from `self`
-      def _path_to?(other, visited = new_vertex_set)
-        return false unless visited.add?(self)
-        return true if equal?(other)
-        successors.any? { |v| v._path_to?(other, visited) }
-      end
-      protected :_path_to?
-
-      # Is there a path from `other` to `self` following edges in the
-      # dependency graph?
-      # @return whether there is a path following edges within this {#graph}
-      def ancestor?(other)
-        other.path_to?(self)
-      end
-
-      alias is_reachable_from? ancestor?
-
-      def new_vertex_set
-        require 'set'
-        Set.new
-      end
-      private :new_vertex_set
-    end
-  end
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/errors.rb b/lib/bundler/vendor/molinillo/lib/molinillo/errors.rb
deleted file mode 100644
index e210202b69..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/errors.rb
+++ /dev/null
@@ -1,143 +0,0 @@
-# frozen_string_literal: true
-
-module Bundler::Molinillo
-  # An error that occurred during the resolution process
-  class ResolverError < StandardError; end
-
-  # An error caused by searching for a dependency that is completely unknown,
-  # i.e. has no versions available whatsoever.
-  class NoSuchDependencyError < ResolverError
-    # @return [Object] the dependency that could not be found
-    attr_accessor :dependency
-
-    # @return [Array<Object>] the specifications that depended upon {#dependency}
-    attr_accessor :required_by
-
-    # Initializes a new error with the given missing dependency.
-    # @param [Object] dependency @see {#dependency}
-    # @param [Array<Object>] required_by @see {#required_by}
-    def initialize(dependency, required_by = [])
-      @dependency = dependency
-      @required_by = required_by.uniq
-      super()
-    end
-
-    # The error message for the missing dependency, including the specifications
-    # that had this dependency.
-    def message
-      sources = required_by.map { |r| "`#{r}`" }.join(' and ')
-      message = "Unable to find a specification for `#{dependency}`"
-      message += " depended upon by #{sources}" unless sources.empty?
-      message
-    end
-  end
-
-  # An error caused by attempting to fulfil a dependency that was circular
-  #
-  # @note This exception will be thrown if and only if a {Vertex} is added to a
-  #   {DependencyGraph} that has a {DependencyGraph::Vertex#path_to?} an
-  #   existing {DependencyGraph::Vertex}
-  class CircularDependencyError < ResolverError
-    # [Set<Object>] the dependencies responsible for causing the error
-    attr_reader :dependencies
-
-    # Initializes a new error with the given circular vertices.
-    # @param [Array<DependencyGraph::Vertex>] vertices the vertices in the dependency
-    #   that caused the error
-    def initialize(vertices)
-      super "There is a circular dependency between #{vertices.map(&:name).join(' and ')}"
-      @dependencies = vertices.map { |vertex| vertex.payload.possibilities.last }.to_set
-    end
-  end
-
-  # An error caused by conflicts in version
-  class VersionConflict < ResolverError
-    # @return [{String => Resolution::Conflict}] the conflicts that caused
-    #   resolution to fail
-    attr_reader :conflicts
-
-    # @return [SpecificationProvider] the specification provider used during
-    #   resolution
-    attr_reader :specification_provider
-
-    # Initializes a new error with the given version conflicts.
-    # @param [{String => Resolution::Conflict}] conflicts see {#conflicts}
-    # @param [SpecificationProvider] specification_provider see {#specification_provider}
-    def initialize(conflicts, specification_provider)
-      pairs = []
-      conflicts.values.flat_map(&:requirements).each do |conflicting|
-        conflicting.each do |source, conflict_requirements|
-          conflict_requirements.each do |c|
-            pairs << [c, source]
-          end
-        end
-      end
-
-      super "Unable to satisfy the following requirements:\n\n" \
-        "#{pairs.map { |r, d| "- `#{r}` required by `#{d}`" }.join("\n")}"
-
-      @conflicts = conflicts
-      @specification_provider = specification_provider
-    end
-
-    require_relative 'delegates/specification_provider'
-    include Delegates::SpecificationProvider
-
-    # @return [String] An error message that includes requirement trees,
-    #   which is much more detailed & customizable than the default message
-    # @param [Hash] opts the options to create a message with.
-    # @option opts [String] :solver_name The user-facing name of the solver
-    # @option opts [String] :possibility_type The generic name of a possibility
-    # @option opts [Proc] :reduce_trees A proc that reduced the list of requirement trees
-    # @option opts [Proc] :printable_requirement A proc that pretty-prints requirements
-    # @option opts [Proc] :additional_message_for_conflict A proc that appends additional
-    #   messages for each conflict
-    # @option opts [Proc] :version_for_spec A proc that returns the version number for a
-    #   possibility
-    def message_with_trees(opts = {})
-      solver_name = opts.delete(:solver_name) { self.class.name.split('::').first }
-      possibility_type = opts.delete(:possibility_type) { 'possibility named' }
-      reduce_trees = opts.delete(:reduce_trees) { proc { |trees| trees.uniq.sort_by(&:to_s) } }
-      printable_requirement = opts.delete(:printable_requirement) { proc { |req| req.to_s } }
-      additional_message_for_conflict = opts.delete(:additional_message_for_conflict) { proc {} }
-      version_for_spec = opts.delete(:version_for_spec) { proc(&:to_s) }
-      incompatible_version_message_for_conflict = opts.delete(:incompatible_version_message_for_conflict) do
-        proc do |name, _conflict|
-          %(#{solver_name} could not find compatible versions for #{possibility_type} "#{name}":)
-        end
-      end
-
-      conflicts.sort.reduce(''.dup) do |o, (name, conflict)|
-        o << "\n" << incompatible_version_message_for_conflict.call(name, conflict) << "\n"
-        if conflict.locked_requirement
-          o << %(  In snapshot (#{name_for_locking_dependency_source}):\n)
-          o << %(    #{printable_requirement.call(conflict.locked_requirement)}\n)
-          o << %(\n)
-        end
-        o << %(  In #{name_for_explicit_dependency_source}:\n)
-        trees = reduce_trees.call(conflict.requirement_trees)
-
-        o << trees.map do |tree|
-          t = ''.dup
-          depth = 2
-          tree.each do |req|
-            t << '  ' * depth << printable_requirement.call(req)
-            unless tree.last == req
-              if spec = conflict.activated_by_name[name_for(req)]
-                t << %( was resolved to #{version_for_spec.call(spec)}, which)
-              end
-              t << %( depends on)
-            end
-            t << %(\n)
-            depth += 1
-          end
-          t
-        end.join("\n")
-
-        additional_message_for_conflict.call(o, name, conflict)
-
-        o
-      end.strip
-    end
-  end
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/gem_metadata.rb b/lib/bundler/vendor/molinillo/lib/molinillo/gem_metadata.rb
deleted file mode 100644
index e13a781a50..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/gem_metadata.rb
+++ /dev/null
@@ -1,6 +0,0 @@
-# frozen_string_literal: true
-
-module Bundler::Molinillo
-  # The version of Bundler::Molinillo.
-  VERSION = '0.7.0'.freeze
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/modules/specification_provider.rb b/lib/bundler/vendor/molinillo/lib/molinillo/modules/specification_provider.rb
deleted file mode 100644
index eeae79af3c..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/modules/specification_provider.rb
+++ /dev/null
@@ -1,112 +0,0 @@
-# frozen_string_literal: true
-
-module Bundler::Molinillo
-  # Provides information about specifications and dependencies to the resolver,
-  # allowing the {Resolver} class to remain generic while still providing power
-  # and flexibility.
-  #
-  # This module contains the methods that users of Bundler::Molinillo must to implement,
-  # using knowledge of their own model classes.
-  module SpecificationProvider
-    # Search for the specifications that match the given dependency.
-    # The specifications in the returned array will be considered in reverse
-    # order, so the latest version ought to be last.
-    # @note This method should be 'pure', i.e. the return value should depend
-    #   only on the `dependency` parameter.
-    #
-    # @param [Object] dependency
-    # @return [Array<Object>] the specifications that satisfy the given
-    #   `dependency`.
-    def search_for(dependency)
-      []
-    end
-
-    # Returns the dependencies of `specification`.
-    # @note This method should be 'pure', i.e. the return value should depend
-    #   only on the `specification` parameter.
-    #
-    # @param [Object] specification
-    # @return [Array<Object>] the dependencies that are required by the given
-    #   `specification`.
-    def dependencies_for(specification)
-      []
-    end
-
-    # Determines whether the given `requirement` is satisfied by the given
-    # `spec`, in the context of the current `activated` dependency graph.
-    #
-    # @param [Object] requirement
-    # @param [DependencyGraph] activated the current dependency graph in the
-    #   resolution process.
-    # @param [Object] spec
-    # @return [Boolean] whether `requirement` is satisfied by `spec` in the
-    #   context of the current `activated` dependency graph.
-    def requirement_satisfied_by?(requirement, activated, spec)
-      true
-    end
-
-    # Determines whether two arrays of dependencies are equal, and thus can be
-    # grouped.
-    #
-    # @param [Array<Object>] dependencies
-    # @param [Array<Object>] other_dependencies
-    # @return [Boolean] whether `dependencies` and `other_dependencies` should
-    #   be considered equal.
-    def dependencies_equal?(dependencies, other_dependencies)
-      dependencies == other_dependencies
-    end
-
-    # Returns the name for the given `dependency`.
-    # @note This method should be 'pure', i.e. the return value should depend
-    #   only on the `dependency` parameter.
-    #
-    # @param [Object] dependency
-    # @return [String] the name for the given `dependency`.
-    def name_for(dependency)
-      dependency.to_s
-    end
-
-    # @return [String] the name of the source of explicit dependencies, i.e.
-    #   those passed to {Resolver#resolve} directly.
-    def name_for_explicit_dependency_source
-      'user-specified dependency'
-    end
-
-    # @return [String] the name of the source of 'locked' dependencies, i.e.
-    #   those passed to {Resolver#resolve} directly as the `base`
-    def name_for_locking_dependency_source
-      'Lockfile'
-    end
-
-    # Sort dependencies so that the ones that are easiest to resolve are first.
-    # Easiest to resolve is (usually) defined by:
-    #   1) Is this dependency already activated?
-    #   2) How relaxed are the requirements?
-    #   3) Are there any conflicts for this dependency?
-    #   4) How many possibilities are there to satisfy this dependency?
-    #
-    # @param [Array<Object>] dependencies
-    # @param [DependencyGraph] activated the current dependency graph in the
-    #   resolution process.
-    # @param [{String => Array<Conflict>}] conflicts
-    # @return [Array<Object>] a sorted copy of `dependencies`.
-    def sort_dependencies(dependencies, activated, conflicts)
-      dependencies.sort_by do |dependency|
-        name = name_for(dependency)
-        [
-          activated.vertex_named(name).payload ? 0 : 1,
-          conflicts[name] ? 0 : 1,
-        ]
-      end
-    end
-
-    # Returns whether this dependency, which has no possible matching
-    # specifications, can safely be ignored.
-    #
-    # @param [Object] dependency
-    # @return [Boolean] whether this dependency can safely be skipped.
-    def allow_missing?(dependency)
-      false
-    end
-  end
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/modules/ui.rb b/lib/bundler/vendor/molinillo/lib/molinillo/modules/ui.rb
deleted file mode 100644
index a166bc6991..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/modules/ui.rb
+++ /dev/null
@@ -1,67 +0,0 @@
-# frozen_string_literal: true
-
-module Bundler::Molinillo
-  # Conveys information about the resolution process to a user.
-  module UI
-    # The {IO} object that should be used to print output. `STDOUT`, by default.
-    #
-    # @return [IO]
-    def output
-      STDOUT
-    end
-
-    # Called roughly every {#progress_rate}, this method should convey progress
-    # to the user.
-    #
-    # @return [void]
-    def indicate_progress
-      output.print '.' unless debug?
-    end
-
-    # How often progress should be conveyed to the user via
-    # {#indicate_progress}, in seconds. A third of a second, by default.
-    #
-    # @return [Float]
-    def progress_rate
-      0.33
-    end
-
-    # Called before resolution begins.
-    #
-    # @return [void]
-    def before_resolution
-      output.print 'Resolving dependencies...'
-    end
-
-    # Called after resolution ends (either successfully or with an error).
-    # By default, prints a newline.
-    #
-    # @return [void]
-    def after_resolution
-      output.puts
-    end
-
-    # Conveys debug information to the user.
-    #
-    # @param [Integer] depth the current depth of the resolution process.
-    # @return [void]
-    def debug(depth = 0)
-      if debug?
-        debug_info = yield
-        debug_info = debug_info.inspect unless debug_info.is_a?(String)
-        debug_info = debug_info.split("\n").map { |s| ":#{depth.to_s.rjust 4}: #{s}" }
-        output.puts debug_info
-      end
-    end
-
-    # Whether or not debug messages should be printed.
-    # By default, whether or not the `MOLINILLO_DEBUG` environment variable is
-    # set.
-    #
-    # @return [Boolean]
-    def debug?
-      return @debug_mode if defined?(@debug_mode)
-      @debug_mode = ENV['MOLINILLO_DEBUG']
-    end
-  end
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/resolution.rb b/lib/bundler/vendor/molinillo/lib/molinillo/resolution.rb
deleted file mode 100644
index c689ca7635..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/resolution.rb
+++ /dev/null
@@ -1,839 +0,0 @@
-# frozen_string_literal: true
-
-module Bundler::Molinillo
-  class Resolver
-    # A specific resolution from a given {Resolver}
-    class Resolution
-      # A conflict that the resolution process encountered
-      # @attr [Object] requirement the requirement that immediately led to the conflict
-      # @attr [{String,Nil=>[Object]}] requirements the requirements that caused the conflict
-      # @attr [Object, nil] existing the existing spec that was in conflict with
-      #   the {#possibility}
-      # @attr [Object] possibility_set the set of specs that was unable to be
-      #   activated due to a conflict.
-      # @attr [Object] locked_requirement the relevant locking requirement.
-      # @attr [Array<Array<Object>>] requirement_trees the different requirement
-      #   trees that led to every requirement for the conflicting name.
-      # @attr [{String=>Object}] activated_by_name the already-activated specs.
-      # @attr [Object] underlying_error an error that has occurred during resolution, and
-      #    will be raised at the end of it if no resolution is found.
-      Conflict = Struct.new(
-        :requirement,
-        :requirements,
-        :existing,
-        :possibility_set,
-        :locked_requirement,
-        :requirement_trees,
-        :activated_by_name,
-        :underlying_error
-      )
-
-      class Conflict
-        # @return [Object] a spec that was unable to be activated due to a conflict
-        def possibility
-          possibility_set && possibility_set.latest_version
-        end
-      end
-
-      # A collection of possibility states that share the same dependencies
-      # @attr [Array] dependencies the dependencies for this set of possibilities
-      # @attr [Array] possibilities the possibilities
-      PossibilitySet = Struct.new(:dependencies, :possibilities)
-
-      class PossibilitySet
-        # String representation of the possibility set, for debugging
-        def to_s
-          "[#{possibilities.join(', ')}]"
-        end
-
-        # @return [Object] most up-to-date dependency in the possibility set
-        def latest_version
-          possibilities.last
-        end
-      end
-
-      # Details of the state to unwind to when a conflict occurs, and the cause of the unwind
-      # @attr [Integer] state_index the index of the state to unwind to
-      # @attr [Object] state_requirement the requirement of the state we're unwinding to
-      # @attr [Array] requirement_tree for the requirement we're relaxing
-      # @attr [Array] conflicting_requirements the requirements that combined to cause the conflict
-      # @attr [Array] requirement_trees for the conflict
-      # @attr [Array] requirements_unwound_to_instead array of unwind requirements that were chosen over this unwind
-      UnwindDetails = Struct.new(
-        :state_index,
-        :state_requirement,
-        :requirement_tree,
-        :conflicting_requirements,
-        :requirement_trees,
-        :requirements_unwound_to_instead
-      )
-
-      class UnwindDetails
-        include Comparable
-
-        # We compare UnwindDetails when choosing which state to unwind to. If
-        # two options have the same state_index we prefer the one most
-        # removed from a requirement that caused the conflict. Both options
-        # would unwind to the same state, but a `grandparent` option will
-        # filter out fewer of its possibilities after doing so - where a state
-        # is both a `parent` and a `grandparent` to requirements that have
-        # caused a conflict this is the correct behaviour.
-        # @param [UnwindDetail] other UnwindDetail to be compared
-        # @return [Integer] integer specifying ordering
-        def <=>(other)
-          if state_index > other.state_index
-            1
-          elsif state_index == other.state_index
-            reversed_requirement_tree_index <=> other.reversed_requirement_tree_index
-          else
-            -1
-          end
-        end
-
-        # @return [Integer] index of state requirement in reversed requirement tree
-        #    (the conflicting requirement itself will be at position 0)
-        def reversed_requirement_tree_index
-          @reversed_requirement_tree_index ||=
-            if state_requirement
-              requirement_tree.reverse.index(state_requirement)
-            else
-              999_999
-            end
-        end
-
-        # @return [Boolean] where the requirement of the state we're unwinding
-        #    to directly caused the conflict. Note: in this case, it is
-        #    impossible for the state we're unwinding to to be a parent of
-        #    any of the other conflicting requirements (or we would have
-        #    circularity)
-        def unwinding_to_primary_requirement?
-          requirement_tree.last == state_requirement
-        end
-
-        # @return [Array] array of sub-dependencies to avoid when choosing a
-        #    new possibility for the state we've unwound to. Only relevant for
-        #    non-primary unwinds
-        def sub_dependencies_to_avoid
-          @requirements_to_avoid ||=
-            requirement_trees.map do |tree|
-              index = tree.index(state_requirement)
-              tree[index + 1] if index
-            end.compact
-        end
-
-        # @return [Array] array of all the requirements that led to the need for
-        #    this unwind
-        def all_requirements
-          @all_requirements ||= requirement_trees.flatten(1)
-        end
-      end
-
-      # @return [SpecificationProvider] the provider that knows about
-      #   dependencies, requirements, specifications, versions, etc.
-      attr_reader :specification_provider
-
-      # @return [UI] the UI that knows how to communicate feedback about the
-      #   resolution process back to the user
-      attr_reader :resolver_ui
-
-      # @return [DependencyGraph] the base dependency graph to which
-      #   dependencies should be 'locked'
-      attr_reader :base
-
-      # @return [Array] the dependencies that were explicitly required
-      attr_reader :original_requested
-
-      # Initializes a new resolution.
-      # @param [SpecificationProvider] specification_provider
-      #   see {#specification_provider}
-      # @param [UI] resolver_ui see {#resolver_ui}
-      # @param [Array] requested see {#original_requested}
-      # @param [DependencyGraph] base see {#base}
-      def initialize(specification_provider, resolver_ui, requested, base)
-        @specification_provider = specification_provider
-        @resolver_ui = resolver_ui
-        @original_requested = requested
-        @base = base
-        @states = []
-        @iteration_counter = 0
-        @parents_of = Hash.new { |h, k| h[k] = [] }
-      end
-
-      # Resolves the {#original_requested} dependencies into a full dependency
-      #   graph
-      # @raise [ResolverError] if successful resolution is impossible
-      # @return [DependencyGraph] the dependency graph of successfully resolved
-      #   dependencies
-      def resolve
-        start_resolution
-
-        while state
-          break if !state.requirement && state.requirements.empty?
-          indicate_progress
-          if state.respond_to?(:pop_possibility_state) # DependencyState
-            debug(depth) { "Creating possibility state for #{requirement} (#{possibilities.count} remaining)" }
-            state.pop_possibility_state.tap do |s|
-              if s
-                states.push(s)
-                activated.tag(s)
-              end
-            end
-          end
-          process_topmost_state
-        end
-
-        resolve_activated_specs
-      ensure
-        end_resolution
-      end
-
-      # @return [Integer] the number of resolver iterations in between calls to
-      #   {#resolver_ui}'s {UI#indicate_progress} method
-      attr_accessor :iteration_rate
-      private :iteration_rate
-
-      # @return [Time] the time at which resolution began
-      attr_accessor :started_at
-      private :started_at
-
-      # @return [Array<ResolutionState>] the stack of states for the resolution
-      attr_accessor :states
-      private :states
-
-      private
-
-      # Sets up the resolution process
-      # @return [void]
-      def start_resolution
-        @started_at = Time.now
-
-        push_initial_state
-
-        debug { "Starting resolution (#{@started_at})\nUser-requested dependencies: #{original_requested}" }
-        resolver_ui.before_resolution
-      end
-
-      def resolve_activated_specs
-        activated.vertices.each do |_, vertex|
-          next unless vertex.payload
-
-          latest_version = vertex.payload.possibilities.reverse_each.find do |possibility|
-            vertex.requirements.all? { |req| requirement_satisfied_by?(req, activated, possibility) }
-          end
-
-          activated.set_payload(vertex.name, latest_version)
-        end
-        activated.freeze
-      end
-
-      # Ends the resolution process
-      # @return [void]
-      def end_resolution
-        resolver_ui.after_resolution
-        debug do
-          "Finished resolution (#{@iteration_counter} steps) " \
-          "(Took #{(ended_at = Time.now) - @started_at} seconds) (#{ended_at})"
-        end
-        debug { 'Unactivated: ' + Hash[activated.vertices.reject { |_n, v| v.payload }].keys.join(', ') } if state
-        debug { 'Activated: ' + Hash[activated.vertices.select { |_n, v| v.payload }].keys.join(', ') } if state
-      end
-
-      require_relative 'state'
-      require_relative 'modules/specification_provider'
-
-      require_relative 'delegates/resolution_state'
-      require_relative 'delegates/specification_provider'
-
-      include Bundler::Molinillo::Delegates::ResolutionState
-      include Bundler::Molinillo::Delegates::SpecificationProvider
-
-      # Processes the topmost available {RequirementState} on the stack
-      # @return [void]
-      def process_topmost_state
-        if possibility
-          attempt_to_activate
-        else
-          create_conflict
-          unwind_for_conflict
-        end
-      rescue CircularDependencyError => underlying_error
-        create_conflict(underlying_error)
-        unwind_for_conflict
-      end
-
-      # @return [Object] the current possibility that the resolution is trying
-      #   to activate
-      def possibility
-        possibilities.last
-      end
-
-      # @return [RequirementState] the current state the resolution is
-      #   operating upon
-      def state
-        states.last
-      end
-
-      # Creates and pushes the initial state for the resolution, based upon the
-      # {#requested} dependencies
-      # @return [void]
-      def push_initial_state
-        graph = DependencyGraph.new.tap do |dg|
-          original_requested.each do |requested|
-            vertex = dg.add_vertex(name_for(requested), nil, true)
-            vertex.explicit_requirements << requested
-          end
-          dg.tag(:initial_state)
-        end
-
-        push_state_for_requirements(original_requested, true, graph)
-      end
-
-      # Unwinds the states stack because a conflict has been encountered
-      # @return [void]
-      def unwind_for_conflict
-        details_for_unwind = build_details_for_unwind
-        unwind_options = unused_unwind_options
-        debug(depth) { "Unwinding for conflict: #{requirement} to #{details_for_unwind.state_index / 2}" }
-        conflicts.tap do |c|
-          sliced_states = states.slice!((details_for_unwind.state_index + 1)..-1)
-          raise_error_unless_state(c)
-          activated.rewind_to(sliced_states.first || :initial_state) if sliced_states
-          state.conflicts = c
-          state.unused_unwind_options = unwind_options
-          filter_possibilities_after_unwind(details_for_unwind)
-          index = states.size - 1
-          @parents_of.each { |_, a| a.reject! { |i| i >= index } }
-          state.unused_unwind_options.reject! { |uw| uw.state_index >= index }
-        end
-      end
-
-      # Raises a VersionConflict error, or any underlying error, if there is no
-      # current state
-      # @return [void]
-      def raise_error_unless_state(conflicts)
-        return if state
-
-        error = conflicts.values.map(&:underlying_error).compact.first
-        raise error || VersionConflict.new(conflicts, specification_provider)
-      end
-
-      # @return [UnwindDetails] Details of the nearest index to which we could unwind
-      def build_details_for_unwind
-        # Get the possible unwinds for the current conflict
-        current_conflict = conflicts[name]
-        binding_requirements = binding_requirements_for_conflict(current_conflict)
-        unwind_details = unwind_options_for_requirements(binding_requirements)
-
-        last_detail_for_current_unwind = unwind_details.sort.last
-        current_detail = last_detail_for_current_unwind
-
-        # Look for past conflicts that could be unwound to affect the
-        # requirement tree for the current conflict
-        all_reqs = last_detail_for_current_unwind.all_requirements
-        all_reqs_size = all_reqs.size
-        relevant_unused_unwinds = unused_unwind_options.select do |alternative|
-          diff_reqs = all_reqs - alternative.requirements_unwound_to_instead
-          next if diff_reqs.size == all_reqs_size
-          # Find the highest index unwind whilst looping through
-          current_detail = alternative if alternative > current_detail
-          alternative
-        end
-
-        # Add the current unwind options to the `unused_unwind_options` array.
-        # The "used" option will be filtered out during `unwind_for_conflict`.
-        state.unused_unwind_options += unwind_details.reject { |detail| detail.state_index == -1 }
-
-        # Update the requirements_unwound_to_instead on any relevant unused unwinds
-        relevant_unused_unwinds.each do |d|
-          (d.requirements_unwound_to_instead << current_detail.state_requirement).uniq!
-        end
-        unwind_details.each do |d|
-          (d.requirements_unwound_to_instead << current_detail.state_requirement).uniq!
-        end
-
-        current_detail
-      end
-
-      # @param [Array<Object>] binding_requirements array of requirements that combine to create a conflict
-      # @return [Array<UnwindDetails>] array of UnwindDetails that have a chance
-      #    of resolving the passed requirements
-      def unwind_options_for_requirements(binding_requirements)
-        unwind_details = []
-
-        trees = []
-        binding_requirements.reverse_each do |r|
-          partial_tree = [r]
-          trees << partial_tree
-          unwind_details << UnwindDetails.new(-1, nil, partial_tree, binding_requirements, trees, [])
-
-          # If this requirement has alternative possibilities, check if any would
-          # satisfy the other requirements that created this conflict
-          requirement_state = find_state_for(r)
-          if conflict_fixing_possibilities?(requirement_state, binding_requirements)
-            unwind_details << UnwindDetails.new(
-              states.index(requirement_state),
-              r,
-              partial_tree,
-              binding_requirements,
-              trees,
-              []
-            )
-          end
-
-          # Next, look at the parent of this requirement, and check if the requirement
-          # could have been avoided if an alternative PossibilitySet had been chosen
-          parent_r = parent_of(r)
-          next if parent_r.nil?
-          partial_tree.unshift(parent_r)
-          requirement_state = find_state_for(parent_r)
-          if requirement_state.possibilities.any? { |set| !set.dependencies.include?(r) }
-            unwind_details << UnwindDetails.new(
-              states.index(requirement_state),
-              parent_r,
-              partial_tree,
-              binding_requirements,
-              trees,
-              []
-            )
-          end
-
-          # Finally, look at the grandparent and up of this requirement, looking
-          # for any possibilities that wouldn't create their parent requirement
-          grandparent_r = parent_of(parent_r)
-          until grandparent_r.nil?
-            partial_tree.unshift(grandparent_r)
-            requirement_state = find_state_for(grandparent_r)
-            if requirement_state.possibilities.any? { |set| !set.dependencies.include?(parent_r) }
-              unwind_details << UnwindDetails.new(
-                states.index(requirement_state),
-                grandparent_r,
-                partial_tree,
-                binding_requirements,
-                trees,
-                []
-              )
-            end
-            parent_r = grandparent_r
-            grandparent_r = parent_of(parent_r)
-          end
-        end
-
-        unwind_details
-      end
-
-      # @param [DependencyState] state
-      # @param [Array] binding_requirements array of requirements
-      # @return [Boolean] whether or not the given state has any possibilities
-      #    that could satisfy the given requirements
-      def conflict_fixing_possibilities?(state, binding_requirements)
-        return false unless state
-
-        state.possibilities.any? do |possibility_set|
-          possibility_set.possibilities.any? do |poss|
-            possibility_satisfies_requirements?(poss, binding_requirements)
-          end
-        end
-      end
-
-      # Filter's a state's possibilities to remove any that would not fix the
-      # conflict we've just rewound from
-      # @param [UnwindDetails] unwind_details details of the conflict just
-      #   unwound from
-      # @return [void]
-      def filter_possibilities_after_unwind(unwind_details)
-        return unless state && !state.possibilities.empty?
-
-        if unwind_details.unwinding_to_primary_requirement?
-          filter_possibilities_for_primary_unwind(unwind_details)
-        else
-          filter_possibilities_for_parent_unwind(unwind_details)
-        end
-      end
-
-      # Filter's a state's possibilities to remove any that would not satisfy
-      # the requirements in the conflict we've just rewound from
-      # @param [UnwindDetails] unwind_details details of the conflict just unwound from
-      # @return [void]
-      def filter_possibilities_for_primary_unwind(unwind_details)
-        unwinds_to_state = unused_unwind_options.select { |uw| uw.state_index == unwind_details.state_index }
-        unwinds_to_state << unwind_details
-        unwind_requirement_sets = unwinds_to_state.map(&:conflicting_requirements)
-
-        state.possibilities.reject! do |possibility_set|
-          possibility_set.possibilities.none? do |poss|
-            unwind_requirement_sets.any? do |requirements|
-              possibility_satisfies_requirements?(poss, requirements)
-            end
-          end
-        end
-      end
-
-      # @param [Object] possibility a single possibility
-      # @param [Array] requirements an array of requirements
-      # @return [Boolean] whether the possibility satisfies all of the
-      #    given requirements
-      def possibility_satisfies_requirements?(possibility, requirements)
-        name = name_for(possibility)
-
-        activated.tag(:swap)
-        activated.set_payload(name, possibility) if activated.vertex_named(name)
-        satisfied = requirements.all? { |r| requirement_satisfied_by?(r, activated, possibility) }
-        activated.rewind_to(:swap)
-
-        satisfied
-      end
-
-      # Filter's a state's possibilities to remove any that would (eventually)
-      # create a requirement in the conflict we've just rewound from
-      # @param [UnwindDetails] unwind_details details of the conflict just unwound from
-      # @return [void]
-      def filter_possibilities_for_parent_unwind(unwind_details)
-        unwinds_to_state = unused_unwind_options.select { |uw| uw.state_index == unwind_details.state_index }
-        unwinds_to_state << unwind_details
-
-        primary_unwinds = unwinds_to_state.select(&:unwinding_to_primary_requirement?).uniq
-        parent_unwinds = unwinds_to_state.uniq - primary_unwinds
-
-        allowed_possibility_sets = primary_unwinds.flat_map do |unwind|
-          states[unwind.state_index].possibilities.select do |possibility_set|
-            possibility_set.possibilities.any? do |poss|
-              possibility_satisfies_requirements?(poss, unwind.conflicting_requirements)
-            end
-          end
-        end
-
-        requirements_to_avoid = parent_unwinds.flat_map(&:sub_dependencies_to_avoid)
-
-        state.possibilities.reject! do |possibility_set|
-          !allowed_possibility_sets.include?(possibility_set) &&
-            (requirements_to_avoid - possibility_set.dependencies).empty?
-        end
-      end
-
-      # @param [Conflict] conflict
-      # @return [Array] minimal array of requirements that would cause the passed
-      #    conflict to occur.
-      def binding_requirements_for_conflict(conflict)
-        return [conflict.requirement] if conflict.possibility.nil?
-
-        possible_binding_requirements = conflict.requirements.values.flatten(1).uniq
-
-        # When there's a `CircularDependency` error the conflicting requirement
-        # (the one causing the circular) won't be `conflict.requirement`
-        # (which won't be for the right state, because we won't have created it,
-        # because it's circular).
-        # We need to make sure we have that requirement in the conflict's list,
-        # otherwise we won't be able to unwind properly, so we just return all
-        # the requirements for the conflict.
-        return possible_binding_requirements if conflict.underlying_error
-
-        possibilities = search_for(conflict.requirement)
-
-        # If all the requirements together don't filter out all possibilities,
-        # then the only two requirements we need to consider are the initial one
-        # (where the dependency's version was first chosen) and the last
-        if binding_requirement_in_set?(nil, possible_binding_requirements, possibilities)
-          return [conflict.requirement, requirement_for_existing_name(name_for(conflict.requirement))].compact
-        end
-
-        # Loop through the possible binding requirements, removing each one
-        # that doesn't bind. Use a `reverse_each` as we want the earliest set of
-        # binding requirements, and don't use `reject!` as we wish to refine the
-        # array *on each iteration*.
-        binding_requirements = possible_binding_requirements.dup
-        possible_binding_requirements.reverse_each do |req|
-          next if req == conflict.requirement
-          unless binding_requirement_in_set?(req, binding_requirements, possibilities)
-            binding_requirements -= [req]
-          end
-        end
-
-        binding_requirements
-      end
-
-      # @param [Object] requirement we wish to check
-      # @param [Array] possible_binding_requirements array of requirements
-      # @param [Array] possibilities array of possibilities the requirements will be used to filter
-      # @return [Boolean] whether or not the given requirement is required to filter
-      #    out all elements of the array of possibilities.
-      def binding_requirement_in_set?(requirement, possible_binding_requirements, possibilities)
-        possibilities.any? do |poss|
-          possibility_satisfies_requirements?(poss, possible_binding_requirements - [requirement])
-        end
-      end
-
-      # @param [Object] requirement
-      # @return [Object] the requirement that led to `requirement` being added
-      #   to the list of requirements.
-      def parent_of(requirement)
-        return unless requirement
-        return unless index = @parents_of[requirement].last
-        return unless parent_state = @states[index]
-        parent_state.requirement
-      end
-
-      # @param [String] name
-      # @return [Object] the requirement that led to a version of a possibility
-      #   with the given name being activated.
-      def requirement_for_existing_name(name)
-        return nil unless vertex = activated.vertex_named(name)
-        return nil unless vertex.payload
-        states.find { |s| s.name == name }.requirement
-      end
-
-      # @param [Object] requirement
-      # @return [ResolutionState] the state whose `requirement` is the given
-      #   `requirement`.
-      def find_state_for(requirement)
-        return nil unless requirement
-        states.find { |i| requirement == i.requirement }
-      end
-
-      # @param [Object] underlying_error
-      # @return [Conflict] a {Conflict} that reflects the failure to activate
-      #   the {#possibility} in conjunction with the current {#state}
-      def create_conflict(underlying_error = nil)
-        vertex = activated.vertex_named(name)
-        locked_requirement = locked_requirement_named(name)
-
-        requirements = {}
-        unless vertex.explicit_requirements.empty?
-          requirements[name_for_explicit_dependency_source] = vertex.explicit_requirements
-        end
-        requirements[name_for_locking_dependency_source] = [locked_requirement] if locked_requirement
-        vertex.incoming_edges.each do |edge|
-          (requirements[edge.origin.payload.latest_version] ||= []).unshift(edge.requirement)
-        end
-
-        activated_by_name = {}
-        activated.each { |v| activated_by_name[v.name] = v.payload.latest_version if v.payload }
-        conflicts[name] = Conflict.new(
-          requirement,
-          requirements,
-          vertex.payload && vertex.payload.latest_version,
-          possibility,
-          locked_requirement,
-          requirement_trees,
-          activated_by_name,
-          underlying_error
-        )
-      end
-
-      # @return [Array<Array<Object>>] The different requirement
-      #   trees that led to every requirement for the current spec.
-      def requirement_trees
-        vertex = activated.vertex_named(name)
-        vertex.requirements.map { |r| requirement_tree_for(r) }
-      end
-
-      # @param [Object] requirement
-      # @return [Array<Object>] the list of requirements that led to
-      #   `requirement` being required.
-      def requirement_tree_for(requirement)
-        tree = []
-        while requirement
-          tree.unshift(requirement)
-          requirement = parent_of(requirement)
-        end
-        tree
-      end
-
-      # Indicates progress roughly once every second
-      # @return [void]
-      def indicate_progress
-        @iteration_counter += 1
-        @progress_rate ||= resolver_ui.progress_rate
-        if iteration_rate.nil?
-          if Time.now - started_at >= @progress_rate
-            self.iteration_rate = @iteration_counter
-          end
-        end
-
-        if iteration_rate && (@iteration_counter % iteration_rate) == 0
-          resolver_ui.indicate_progress
-        end
-      end
-
-      # Calls the {#resolver_ui}'s {UI#debug} method
-      # @param [Integer] depth the depth of the {#states} stack
-      # @param [Proc] block a block that yields a {#to_s}
-      # @return [void]
-      def debug(depth = 0, &block)
-        resolver_ui.debug(depth, &block)
-      end
-
-      # Attempts to activate the current {#possibility}
-      # @return [void]
-      def attempt_to_activate
-        debug(depth) { 'Attempting to activate ' + possibility.to_s }
-        existing_vertex = activated.vertex_named(name)
-        if existing_vertex.payload
-          debug(depth) { "Found existing spec (#{existing_vertex.payload})" }
-          attempt_to_filter_existing_spec(existing_vertex)
-        else
-          latest = possibility.latest_version
-          possibility.possibilities.select! do |possibility|
-            requirement_satisfied_by?(requirement, activated, possibility)
-          end
-          if possibility.latest_version.nil?
-            # ensure there's a possibility for better error messages
-            possibility.possibilities << latest if latest
-            create_conflict
-            unwind_for_conflict
-          else
-            activate_new_spec
-          end
-        end
-      end
-
-      # Attempts to update the existing vertex's `PossibilitySet` with a filtered version
-      # @return [void]
-      def attempt_to_filter_existing_spec(vertex)
-        filtered_set = filtered_possibility_set(vertex)
-        if !filtered_set.possibilities.empty?
-          activated.set_payload(name, filtered_set)
-          new_requirements = requirements.dup
-          push_state_for_requirements(new_requirements, false)
-        else
-          create_conflict
-          debug(depth) { "Unsatisfied by existing spec (#{vertex.payload})" }
-          unwind_for_conflict
-        end
-      end
-
-      # Generates a filtered version of the existing vertex's `PossibilitySet` using the
-      # current state's `requirement`
-      # @param [Object] vertex existing vertex
-      # @return [PossibilitySet] filtered possibility set
-      def filtered_possibility_set(vertex)
-        PossibilitySet.new(vertex.payload.dependencies, vertex.payload.possibilities & possibility.possibilities)
-      end
-
-      # @param [String] requirement_name the spec name to search for
-      # @return [Object] the locked spec named `requirement_name`, if one
-      #   is found on {#base}
-      def locked_requirement_named(requirement_name)
-        vertex = base.vertex_named(requirement_name)
-        vertex && vertex.payload
-      end
-
-      # Add the current {#possibility} to the dependency graph of the current
-      # {#state}
-      # @return [void]
-      def activate_new_spec
-        conflicts.delete(name)
-        debug(depth) { "Activated #{name} at #{possibility}" }
-        activated.set_payload(name, possibility)
-        require_nested_dependencies_for(possibility)
-      end
-
-      # Requires the dependencies that the recently activated spec has
-      # @param [Object] possibility_set the PossibilitySet that has just been
-      #   activated
-      # @return [void]
-      def require_nested_dependencies_for(possibility_set)
-        nested_dependencies = dependencies_for(possibility_set.latest_version)
-        debug(depth) { "Requiring nested dependencies (#{nested_dependencies.join(', ')})" }
-        nested_dependencies.each do |d|
-          activated.add_child_vertex(name_for(d), nil, [name_for(possibility_set.latest_version)], d)
-          parent_index = states.size - 1
-          parents = @parents_of[d]
-          parents << parent_index if parents.empty?
-        end
-
-        push_state_for_requirements(requirements + nested_dependencies, !nested_dependencies.empty?)
-      end
-
-      # Pushes a new {DependencyState} that encapsulates both existing and new
-      # requirements
-      # @param [Array] new_requirements
-      # @param [Boolean] requires_sort
-      # @param [Object] new_activated
-      # @return [void]
-      def push_state_for_requirements(new_requirements, requires_sort = true, new_activated = activated)
-        new_requirements = sort_dependencies(new_requirements.uniq, new_activated, conflicts) if requires_sort
-        new_requirement = nil
-        loop do
-          new_requirement = new_requirements.shift
-          break if new_requirement.nil? || states.none? { |s| s.requirement == new_requirement }
-        end
-        new_name = new_requirement ? name_for(new_requirement) : ''.freeze
-        possibilities = possibilities_for_requirement(new_requirement)
-        handle_missing_or_push_dependency_state DependencyState.new(
-          new_name, new_requirements, new_activated,
-          new_requirement, possibilities, depth, conflicts.dup, unused_unwind_options.dup
-        )
-      end
-
-      # Checks a proposed requirement with any existing locked requirement
-      # before generating an array of possibilities for it.
-      # @param [Object] requirement the proposed requirement
-      # @param [Object] activated
-      # @return [Array] possibilities
-      def possibilities_for_requirement(requirement, activated = self.activated)
-        return [] unless requirement
-        if locked_requirement_named(name_for(requirement))
-          return locked_requirement_possibility_set(requirement, activated)
-        end
-
-        group_possibilities(search_for(requirement))
-      end
-
-      # @param [Object] requirement the proposed requirement
-      # @param [Object] activated
-      # @return [Array] possibility set containing only the locked requirement, if any
-      def locked_requirement_possibility_set(requirement, activated = self.activated)
-        all_possibilities = search_for(requirement)
-        locked_requirement = locked_requirement_named(name_for(requirement))
-
-        # Longwinded way to build a possibilities array with either the locked
-        # requirement or nothing in it. Required, since the API for
-        # locked_requirement isn't guaranteed.
-        locked_possibilities = all_possibilities.select do |possibility|
-          requirement_satisfied_by?(locked_requirement, activated, possibility)
-        end
-
-        group_possibilities(locked_possibilities)
-      end
-
-      # Build an array of PossibilitySets, with each element representing a group of
-      # dependency versions that all have the same sub-dependency version constraints
-      # and are contiguous.
-      # @param [Array] possibilities an array of possibilities
-      # @return [Array<PossibilitySet>] an array of possibility sets
-      def group_possibilities(possibilities)
-        possibility_sets = []
-        current_possibility_set = nil
-
-        possibilities.reverse_each do |possibility|
-          dependencies = dependencies_for(possibility)
-          if current_possibility_set && dependencies_equal?(current_possibility_set.dependencies, dependencies)
-            current_possibility_set.possibilities.unshift(possibility)
-          else
-            possibility_sets.unshift(PossibilitySet.new(dependencies, [possibility]))
-            current_possibility_set = possibility_sets.first
-          end
-        end
-
-        possibility_sets
-      end
-
-      # Pushes a new {DependencyState}.
-      # If the {#specification_provider} says to
-      # {SpecificationProvider#allow_missing?} that particular requirement, and
-      # there are no possibilities for that requirement, then `state` is not
-      # pushed, and the vertex in {#activated} is removed, and we continue
-      # resolving the remaining requirements.
-      # @param [DependencyState] state
-      # @return [void]
-      def handle_missing_or_push_dependency_state(state)
-        if state.requirement && state.possibilities.empty? && allow_missing?(state.requirement)
-          state.activated.detach_vertex_named(state.name)
-          push_state_for_requirements(state.requirements.dup, false, state.activated)
-        else
-          states.push(state).tap { activated.tag(state) }
-        end
-      end
-    end
-  end
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/resolver.rb b/lib/bundler/vendor/molinillo/lib/molinillo/resolver.rb
deleted file mode 100644
index 95eaab5991..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/resolver.rb
+++ /dev/null
@@ -1,46 +0,0 @@
-# frozen_string_literal: true
-
-require_relative 'dependency_graph'
-
-module Bundler::Molinillo
-  # This class encapsulates a dependency resolver.
-  # The resolver is responsible for determining which set of dependencies to
-  # activate, with feedback from the {#specification_provider}
-  #
-  #
-  class Resolver
-    require_relative 'resolution'
-
-    # @return [SpecificationProvider] the specification provider used
-    #   in the resolution process
-    attr_reader :specification_provider
-
-    # @return [UI] the UI module used to communicate back to the user
-    #   during the resolution process
-    attr_reader :resolver_ui
-
-    # Initializes a new resolver.
-    # @param  [SpecificationProvider] specification_provider
-    #   see {#specification_provider}
-    # @param  [UI] resolver_ui
-    #   see {#resolver_ui}
-    def initialize(specification_provider, resolver_ui)
-      @specification_provider = specification_provider
-      @resolver_ui = resolver_ui
-    end
-
-    # Resolves the requested dependencies into a {DependencyGraph},
-    # locking to the base dependency graph (if specified)
-    # @param [Array] requested an array of 'requested' dependencies that the
-    #   {#specification_provider} can understand
-    # @param [DependencyGraph,nil] base the base dependency graph to which
-    #   dependencies should be 'locked'
-    def resolve(requested, base = DependencyGraph.new)
-      Resolution.new(specification_provider,
-                     resolver_ui,
-                     requested,
-                     base).
-        resolve
-    end
-  end
-end
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/state.rb b/lib/bundler/vendor/molinillo/lib/molinillo/state.rb
deleted file mode 100644
index 68fa1f54e3..0000000000
--- a/lib/bundler/vendor/molinillo/lib/molinillo/state.rb
+++ /dev/null
@@ -1,58 +0,0 @@
-# frozen_string_literal: true
-
-module Bundler::Molinillo
-  # A state that a {Resolution} can be in
-  # @attr [String] name the name of the current requirement
-  # @attr [Array<Object>] requirements currently unsatisfied requirements
-  # @attr [DependencyGraph] activated the graph of activated dependencies
-  # @attr [Object] requirement the current requirement
-  # @attr [Object] possibilities the possibilities to satisfy the current requirement
-  # @attr [Integer] depth the depth of the resolution
-  # @attr [Hash] conflicts unresolved conflicts, indexed by dependency name
-  # @attr [Array<UnwindDetails>] unused_unwind_options unwinds for previous conflicts that weren't explored
-  ResolutionState = Struct.new(
-    :name,
-    :requirements,
-    :activated,
-    :requirement,
-    :possibilities,
-    :depth,
-    :conflicts,
-    :unused_unwind_options
-  )
-
-  class ResolutionState
-    # Returns an empty resolution state
-    # @return [ResolutionState] an empty state
-    def self.empty
-      new(nil, [], DependencyGraph.new, nil, nil, 0, {}, [])
-    end
-  end
-
-  # A state that encapsulates a set of {#requirements} with an {Array} of
-  # possibilities
-  class DependencyState < ResolutionState
-    # Removes a possibility from `self`
-    # @return [PossibilityState] a state with a single possibility,
-    #  the possibility that was removed from `self`
-    def pop_possibility_state
-      PossibilityState.new(
-        name,
-        requirements.dup,
-        activated,
-        requirement,
-        [possibilities.pop],
-        depth + 1,
-        conflicts.dup,
-        unused_unwind_options.dup
-      ).tap do |state|
-        state.activated.tag(state)
-      end
-    end
-  end
-
-  # A state that encapsulates a single possibility to fulfill the given
-  # {#requirement}
-  class PossibilityState < ResolutionState
-  end
-end
diff --git a/lib/bundler/vendor/net-http-persistent/lib/net/http/persistent.rb b/lib/bundler/vendor/net-http-persistent/lib/net/http/persistent.rb
index beff6d658b..a4e1c5a750 100644
--- a/lib/bundler/vendor/net-http-persistent/lib/net/http/persistent.rb
+++ b/lib/bundler/vendor/net-http-persistent/lib/net/http/persistent.rb
@@ -174,7 +174,7 @@ class Bundler::Persistent::Net::HTTP::Persistent
   ##
   # The version of Bundler::Persistent::Net::HTTP::Persistent you are using
 
-  VERSION = '4.0.0'
+  VERSION = '4.0.1'
 
   ##
   # Error class for errors raised by Bundler::Persistent::Net::HTTP::Persistent.  Various
diff --git a/lib/bundler/vendor/pub_grub/lib/pub_grub.rb b/lib/bundler/vendor/pub_grub/lib/pub_grub.rb
new file mode 100644
index 0000000000..eaaba3fc98
--- /dev/null
+++ b/lib/bundler/vendor/pub_grub/lib/pub_grub.rb
@@ -0,0 +1,31 @@
+require_relative "pub_grub/package"
+require_relative "pub_grub/static_package_source"
+require_relative "pub_grub/term"
+require_relative "pub_grub/version_range"
+require_relative "pub_grub/version_constraint"
+require_relative "pub_grub/version_union"
+require_relative "pub_grub/version_solver"
+require_relative "pub_grub/incompatibility"
+require_relative 'pub_grub/solve_failure'
+require_relative 'pub_grub/failure_writer'
+require_relative 'pub_grub/version'
+
+module Bundler::PubGrub
+  class << self
+    attr_writer :logger
+
+    def logger
+      @logger || default_logger
+    end
+
+    private
+
+    def default_logger
+      require "logger"
+
+      logger = ::Logger.new(STDERR)
+      logger.level = $DEBUG ? ::Logger::DEBUG : ::Logger::WARN
+      @logger = logger
+    end
+  end
+end
diff --git a/lib/bundler/vendor/pub_grub/lib/pub_grub/assignment.rb b/lib/bundler/vendor/pub_grub/lib/pub_grub/assignment.rb
new file mode 100644
index 0000000000..2236a97b5b
--- /dev/null
+++ b/lib/bundler/vendor/pub_grub/lib/pub_grub/assignment.rb
@@ -0,0 +1,20 @@
+module Bundler::PubGrub
+  class Assignment
+    attr_reader :term, :cause, :decision_level, :index
+    def initialize(term, cause, decision_level, index)
+      @term = term
+      @cause = cause
+      @decision_level = decision_level
+      @index = index
+    end
+
+    def self.decision(package, version, decision_level, index)
+      term = Term.new(VersionConstraint.exact(package, version), true)
+      new(term, :decision, decision_level, index)
+    end
+
+    def decision?
+      cause == :decision
+    end
+  end
+end
diff --git a/lib/bundler/vendor/pub_grub/lib/pub_grub/basic_package_source.rb b/lib/bundler/vendor/pub_grub/lib/pub_grub/basic_package_source.rb
new file mode 100644
index 0000000000..dce20d37ad
--- /dev/null
+++ b/lib/bundler/vendor/pub_grub/lib/pub_grub/basic_package_source.rb
@@ -0,0 +1,189 @@
+require_relative 'version_constraint'
+require_relative 'incompatibility'
+
+module Bundler::PubGrub
+  # Types:
+  #
+  # Where possible, Bundler::PubGrub will accept user-defined types, so long as they quack.
+  #
+  # ## "Package":
+  #
+  # This class will be used to represent the various packages being solved for.
+  # .to_s will be called when displaying errors and debugging info, it should
+  # probably return the package's name.
+  # It must also have a reasonable definition of #== and #hash
+  #
+  # Example classes: String ("rails")
+  #
+  #
+  # ## "Version":
+  #
+  # This class will be used to represent a single version number.
+  #
+  # Versions don't need to store their associated package, however they will
+  # only be compared against other versions of the same package.
+  #
+  # It must be Comparible (and implement <=> reasonably)
+  #
+  # Example classes: Gem::Version, Integer
+  #
+  #
+  # ## "Dependency"
+  #
+  # This class represents the requirement one package has on another. It is
+  # returned by dependencies_for(package, version) and will be passed to
+  # parse_dependency to convert it to a format Bundler::PubGrub understands.
+  #
+  # It must also have a reasonable definition of #==
+  #
+  # Example classes: String ("~> 1.0"), Gem::Requirement
+  #
+  class BasicPackageSource
+    # Override me!
+    #
+    # This is called per package to find all possible versions of a package.
+    #
+    # It is called at most once per-package
+    #
+    # Returns: Array of versions for a package, in preferred order of selection
+    def all_versions_for(package)
+      raise NotImplementedError
+    end
+
+    # Override me!
+    #
+    # Returns: Hash in the form of { package => requirement, ... }
+    def dependencies_for(package, version)
+      raise NotImplementedError
+    end
+
+    # Override me!
+    #
+    # Convert a (user-defined) dependency into a format Bundler::PubGrub understands.
+    #
+    # Package is passed to this method but for many implementations is not
+    # needed.
+    #
+    # Returns: either a Bundler::PubGrub::VersionRange, Bundler::PubGrub::VersionUnion, or a
+    #   Bundler::PubGrub::VersionConstraint
+    def parse_dependency(package, dependency)
+      raise NotImplementedError
+    end
+
+    # Override me!
+    #
+    # If not overridden, this will call dependencies_for with the root package.
+    #
+    # Returns: Hash in the form of { package => requirement, ... } (see dependencies_for)
+    def root_dependencies
+      dependencies_for(@root_package, @root_version)
+    end
+
+    # Override me (maybe)
+    #
+    # If not overridden, the order returned by all_versions_for will be used
+    #
+    # Returns: Array of versions in preferred order
+    def sort_versions_by_preferred(package, sorted_versions)
+      indexes = @version_indexes[package]
+      sorted_versions.sort_by { |version| indexes[version] }
+    end
+
+    def initialize
+      @root_package = Package.root
+      @root_version = Package.root_version
+
+      @cached_versions = Hash.new do |h,k|
+        if k == @root_package
+          h[k] = [@root_version]
+        else
+          h[k] = all_versions_for(k)
+        end
+      end
+      @sorted_versions = Hash.new { |h,k| h[k] = @cached_versions[k].sort }
+      @version_indexes = Hash.new { |h,k| h[k] = @cached_versions[k].each.with_index.to_h }
+
+      @cached_dependencies = Hash.new do |packages, package|
+        if package == @root_package
+          packages[package] = {
+            @root_version => root_dependencies
+          }
+        else
+          packages[package] = Hash.new do |versions, version|
+            versions[version] = dependencies_for(package, version)
+          end
+        end
+      end
+    end
+
+    def versions_for(package, range=VersionRange.any)
+      versions = range.select_versions(@sorted_versions[package])
+
+      # Conditional avoids (among other things) calling
+      # sort_versions_by_preferred with the root package
+      if versions.size > 1
+        sort_versions_by_preferred(package, versions)
+      else
+        versions
+      end
+    end
+
+    def no_versions_incompatibility_for(_package, unsatisfied_term)
+      cause = Incompatibility::NoVersions.new(unsatisfied_term)
+
+      Incompatibility.new([unsatisfied_term], cause: cause)
+    end
+
+    def incompatibilities_for(package, version)
+      package_deps = @cached_dependencies[package]
+      sorted_versions = @sorted_versions[package]
+      package_deps[version].map do |dep_package, dep_constraint_name|
+        low = high = sorted_versions.index(version)
+
+        # find version low such that all >= low share the same dep
+        while low > 0 &&
+            package_deps[sorted_versions[low - 1]][dep_package] == dep_constraint_name
+          low -= 1
+        end
+        low =
+          if low == 0
+            nil
+          else
+            sorted_versions[low]
+          end
+
+        # find version high such that all < high share the same dep
+        while high < sorted_versions.length &&
+            package_deps[sorted_versions[high]][dep_package] == dep_constraint_name
+          high += 1
+        end
+        high =
+          if high == sorted_versions.length
+            nil
+          else
+            sorted_versions[high]
+          end
+
+        range = VersionRange.new(min: low, max: high, include_min: true)
+
+        self_constraint = VersionConstraint.new(package, range: range)
+
+        if !@packages.include?(dep_package)
+          # no such package -> this version is invalid
+        end
+
+        dep_constraint = parse_dependency(dep_package, dep_constraint_name)
+        if !dep_constraint
+          # falsey indicates this dependency was invalid
+          cause = Bundler::PubGrub::Incompatibility::InvalidDependency.new(dep_package, dep_constraint_name)
+          return [Incompatibility.new([Term.new(self_constraint, true)], cause: cause)]
+        elsif !dep_constraint.is_a?(VersionConstraint)
+          # Upgrade range/union to VersionConstraint
+          dep_constraint = VersionConstraint.new(dep_package, range: dep_constraint)
+        end
+
+        Incompatibility.new([Term.new(self_constraint, true), Term.new(dep_constraint, false)], cause: :dependency)
+      end
+    end
+  end
+end
diff --git a/lib/bundler/vendor/pub_grub/lib/pub_grub/failure_writer.rb b/lib/bundler/vendor/pub_grub/lib/pub_grub/failure_writer.rb
new file mode 100644
index 0000000000..ee099b23f4
--- /dev/null
+++ b/lib/bundler/vendor/pub_grub/lib/pub_grub/failure_writer.rb
@@ -0,0 +1,182 @@
+module Bundler::PubGrub
+  class FailureWriter
+    def initialize(root)
+      @root = root
+
+      # { Incompatibility => Integer }
+      @derivations = {}
+
+      # [ [ String, Integer or nil ] ]
+      @lines = []
+
+      # { Incompatibility => Integer }
+      @line_numbers = {}
+
+      count_derivations(root)
+    end
+
+    def write
+      return @root.to_s unless @root.conflict?
+
+      visit(@root)
+
+      padding = @line_numbers.empty? ? 0 : "(#{@line_numbers.values.last}) ".length
+
+      @lines.map do |message, number|
+        next "" if message.empty?
+
+        lead = number ? "(#{number}) " : ""
+        lead = lead.ljust(padding)
+        message = message.gsub("\n", "\n" + " " * (padding + 2))
+        "#{lead}#{message}"
+      end.join("\n")
+    end
+
+    private
+
+    def write_line(incompatibility, message, numbered:)
+      if numbered
+        number = @line_numbers.length + 1
+        @line_numbers[incompatibility] = number
+      end
+
+      @lines << [message, number]
+    end
+
+    def visit(incompatibility, conclusion: false)
+      raise unless incompatibility.conflict?
+
+      numbered = conclusion || @derivations[incompatibility] > 1;
+      conjunction = conclusion || incompatibility == @root ? "So," : "And"
+
+      cause = incompatibility.cause
+
+      if cause.conflict.conflict? && cause.other.conflict?
+        conflict_line = @line_numbers[cause.conflict]
+        other_line = @line_numbers[cause.other]
+
+        if conflict_line && other_line
+          write_line(
+            incompatibility,
+            "Because #{cause.conflict} (#{conflict_line})\nand #{cause.other} (#{other_line}),\n#{incompatibility}.",
+            numbered: numbered
+          )
+        elsif conflict_line || other_line
+          with_line    = conflict_line ? cause.conflict : cause.other
+          without_line = conflict_line ? cause.other : cause.conflict
+          line = @line_numbers[with_line]
+
+          visit(without_line);
+          write_line(
+            incompatibility,
+            "#{conjunction} because #{with_line} (#{line}),\n#{incompatibility}.",
+            numbered: numbered
+          )
+        else
+          single_line_conflict = single_line?(cause.conflict.cause)
+          single_line_other    = single_line?(cause.other.cause)
+
+          if single_line_conflict || single_line_other
+            first  = single_line_other ? cause.conflict : cause.other
+            second = single_line_other ? cause.other : cause.conflict
+            visit(first)
+            visit(second)
+            write_line(
+              incompatibility,
+              "Thus, #{incompatibility}.",
+              numbered: numbered
+            )
+          else
+            visit(cause.conflict, conclusion: true)
+            @lines << ["", nil]
+            visit(cause.other)
+
+            write_line(
+              incompatibility,
+              "#{conjunction} because #{cause.conflict} (#{@line_numbers[cause.conflict]}),\n#{incompatibility}.",
+              numbered: numbered
+            )
+          end
+        end
+      elsif cause.conflict.conflict? || cause.other.conflict?
+        derived = cause.conflict.conflict? ? cause.conflict : cause.other
+        ext     = cause.conflict.conflict? ? cause.other : cause.conflict
+
+        derived_line = @line_numbers[derived]
+        if derived_line
+          write_line(
+            incompatibility,
+            "Because #{ext}\nand #{derived} (#{derived_line}),\n#{incompatibility}.",
+            numbered: numbered
+          )
+        elsif collapsible?(derived)
+          derived_cause = derived.cause
+          if derived_cause.conflict.conflict?
+            collapsed_derived = derived_cause.conflict
+            collapsed_ext = derived_cause.other
+          else
+            collapsed_derived = derived_cause.other
+            collapsed_ext = derived_cause.conflict
+          end
+
+          visit(collapsed_derived)
+
+          write_line(
+            incompatibility,
+            "#{conjunction} because #{collapsed_ext}\nand #{ext},\n#{incompatibility}.",
+            numbered: numbered
+          )
+        else
+          visit(derived)
+          write_line(
+            incompatibility,
+            "#{conjunction} because #{ext},\n#{incompatibility}.",
+            numbered: numbered
+          )
+        end
+      else
+        write_line(
+          incompatibility,
+          "Because #{cause.conflict}\nand #{cause.other},\n#{incompatibility}.",
+          numbered: numbered
+        )
+      end
+    end
+
+    def single_line?(cause)
+      !cause.conflict.conflict? && !cause.other.conflict?
+    end
+
+    def collapsible?(incompatibility)
+      return false if @derivations[incompatibility] > 1
+
+      cause = incompatibility.cause
+      # If incompatibility is derived from two derived incompatibilities,
+      # there are too many transitive causes to display concisely.
+      return false if cause.conflict.conflict? && cause.other.conflict?
+
+      # If incompatibility is derived from two external incompatibilities, it
+      # tends to be confusing to collapse it.
+      return false unless cause.conflict.conflict? || cause.other.conflict?
+
+      # If incompatibility's internal cause is numbered, collapsing it would
+      # get too noisy.
+      complex = cause.conflict.conflict? ? cause.conflict : cause.other
+
+      !@line_numbers.has_key?(complex)
+    end
+
+    def count_derivations(incompatibility)
+      if @derivations.has_key?(incompatibility)
+        @derivations[incompatibility] += 1
+      else
+        @derivations[incompatibility] = 1
+        if incompatibility.conflict?
+          cause = incompatibility.cause
+          count_derivations(cause.conflict)
+          count_derivations(cause.other)
+        end
+      end
+    end
+  end
+end
diff --git a/lib/bundler/vendor/pub_grub/lib/pub_grub/incompatibility.rb b/lib/bundler/vendor/pub_grub/lib/pub_grub/incompatibility.rb
new file mode 100644
index 0000000000..239eaf3401
--- /dev/null
+++ b/lib/bundler/vendor/pub_grub/lib/pub_grub/incompatibility.rb
@@ -0,0 +1,150 @@
+module Bundler::PubGrub
+  class Incompatibility
+    ConflictCause = Struct.new(:incompatibility, :satisfier) do
+      alias_method :conflict, :incompatibility
+      alias_method :other, :satisfier
+    end
+
+    InvalidDependency = Struct.new(:package, :constraint) do
+    end
+
+    NoVersions = Struct.new(:constraint) do
+    end
+
+    attr_reader :terms, :cause
+
+    def initialize(terms, cause:, custom_explanation: nil)
+      @cause = cause
+      @terms = cleanup_terms(terms)
+      @custom_explanation = custom_explanation
+
+      if cause == :dependency && @terms.length != 2
+        raise ArgumentError, "a dependency Incompatibility must have exactly two terms. Got #{@terms.inspect}"
+      end
+    end
+
+    def hash
+      cause.hash ^ terms.hash
+    end
+
+    def eql?(other)
+      cause.eql?(other.cause) &&
+        terms.eql?(other.terms)
+    end
+
+    def failure?
+      terms.empty? || (terms.length == 1 && Package.root?(terms[0].package) && terms[0].positive?)
+    end
+
+    def conflict?
+      ConflictCause === cause
+    end
+
+    # Returns all external incompatibilities in this incompatibility's
+    # derivation graph
+    def external_incompatibilities
+      if conflict?
+        [
+          cause.conflict,
+          cause.other
+        ].flat_map(&:external_incompatibilities)
+      else
+        [this]
+      end
+    end
+
+    def to_s
+      return @custom_explanation if @custom_explanation
+
+      case cause
+      when :root
+        "(root dependency)"
+      when :dependency
+        "#{terms[0].to_s(allow_every: true)} depends on #{terms[1].invert}"
+      when Bundler::PubGrub::Incompatibility::InvalidDependency
+        "#{terms[0].to_s(allow_every: true)} depends on unknown package #{cause.package}"
+      when Bundler::PubGrub::Incompatibility::NoVersions
+        "no versions satisfy #{cause.constraint}"
+      when Bundler::PubGrub::Incompatibility::ConflictCause
+        if failure?
+          "version solving has failed"
+        elsif terms.length == 1
+          term = terms[0]
+          if term.positive?
+            if term.constraint.any?
+              "#{term.package} cannot be used"
+            else
+              "#{term.to_s(allow_every: true)} cannot be used"
+            end
+          else
+            "#{term.invert} is required"
+          end
+        else
+          if terms.all?(&:positive?)
+            if terms.length == 2
+              "#{terms[0].to_s(allow_every: true)} is incompatible with #{terms[1]}"
+            else
+              "one of #{terms.map(&:to_s).join(" or ")} must be false"
+            end
+          elsif terms.all?(&:negative?)
+            if terms.length == 2
+              "either #{terms[0].invert} or #{terms[1].invert}"
+            else
+              "one of #{terms.map(&:invert).join(" or ")} must be true";
+            end
+          else
+            positive = terms.select(&:positive?)
+            negative = terms.select(&:negative?).map(&:invert)
+
+            if positive.length == 1
+              "#{positive[0].to_s(allow_every: true)} requires #{negative.join(" or ")}"
+            else
+              "if #{positive.join(" and ")} then #{negative.join(" or ")}"
+            end
+          end
+        end
+      else
+        raise "unhandled cause: #{cause.inspect}"
+      end
+    end
+
+    def inspect
+      "#<#{self.class} #{to_s}>"
+    end
+
+    def pretty_print(q)
+      q.group 2, "#<#{self.class}", ">" do
+        q.breakable
+        q.text to_s
+
+        q.breakable
+        q.text " caused by "
+        q.pp @cause
+      end
+    end
+
+    private
+
+    def cleanup_terms(terms)
+      terms.each do |term|
+        raise "#{term.inspect} must be a term" unless term.is_a?(Term)
+      end
+
+      if terms.length != 1 && ConflictCause === cause
+        terms = terms.reject do |term|
+          term.positive? && Package.root?(term.package)
+        end
+      end
+
+      # Optimized simple cases
+      return terms if terms.length <= 1
+      return terms if terms.length == 2 && terms[0].package != terms[1].package
+
+      terms.group_by(&:package).map do |package, common_terms|
+        common_terms.inject do |acc, term|
+          acc.intersect(term)
+        end
+      end
+    end
+  end
+end
diff --git a/lib/bundler/vendor/pub_grub/lib/pub_grub/package.rb b/lib/bundler/vendor/pub_grub/lib/pub_grub/package.rb
new file mode 100644
index 0000000000..efb9d3da16
--- /dev/null
+++ b/lib/bundler/vendor/pub_grub/lib/pub_grub/package.rb
@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+
+module Bundler::PubGrub
+  class Package
+
+    attr_reader :name
+
+    def initialize(name)
+      @name = name
+    end
+
+    def inspect
+      "#<#{self.class} #{name.inspect}>"
+    end
+
+    def <=>(other)
+      name <=> other.name
+    end
+
+    ROOT = Package.new(:root)
+    ROOT_VERSION = 0
+
+    def self.root
+      ROOT
+    end
+
+    def self.root_version
+      ROOT_VERSION
+    end
+
+    def self.root?(package)
+      if package.respond_to?(:root?)
+        package.root?
+      else
+        package == root
+      end
+    end
+
+    def to_s
+      name.to_s
+    end
+  end
+end
diff --git a/lib/bundler/vendor/pub_grub/lib/pub_grub/partial_solution.rb b/lib/bundler/vendor/pub_grub/lib/pub_grub/partial_solution.rb
new file mode 100644
index 0000000000..4c4b8ca844
--- /dev/null
+++ b/lib/bundler/vendor/pub_grub/lib/pub_grub/partial_solution.rb
@@ -0,0 +1,121 @@
+require_relative 'assignment'
+
+module Bundler::PubGrub
+  class PartialSolution
+    attr_reader :assignments, :decisions
+    attr_reader :attempted_solutions
+
+    def initialize
+      reset!
+
+      @attempted_solutions = 1
+      @backtracking = false
+    end
+
+    def decision_level
+      @decisions.length
+    end
+
+    def relation(term)
+      package = term.package
+      return :overlap if !@terms.key?(package)
+
+      @relation_cache[package][term] ||=
+        @terms[package].relation(term)
+    end
+
+    def satisfies?(term)
+      relation(term) == :subset
+    end
+
+    def derive(term, cause)
+      add_assignment(Assignment.new(term, cause, decision_level, assignments.length))
+    end
+
+    def satisfier(term)
+      assignment =
+        @assignments_by[term.package].bsearch do |assignment_by|
+          @cumulative_assignments[assignment_by].satisfies?(term)
+        end
+
+      assignment || raise("#{term} unsatisfied")
+    end
+
+    # A list of unsatisfied terms
+    def unsatisfied
+      @required.keys.reject do |package|
+        @decisions.key?(package)
+      end.map do |package|
+        @terms[package]
+      end
+    end
+
+    def decide(package, version)
+      @attempted_solutions += 1 if @backtracking
+      @backtracking = false;
+
+      decisions[package] = version
+      assignment = Assignment.decision(package, version, decision_level, assignments.length)
+      add_assignment(assignment)
+    end
+
+    def backtrack(previous_level)
+      @backtracking = true
+
+      new_assignments = assignments.select do |assignment|
+        assignment.decision_level <= previous_level
+      end
+
+      new_decisions = Hash[decisions.first(previous_level)]
+
+      reset!
+
+      @decisions = new_decisions
+
+      new_assignments.each do |assignment|
+        add_assignment(assignment)
+      end
+    end
+
+    private
+
+    def reset!
+      # { Array<Assignment> }
+      @assignments = []
+
+      # { Package => Array<Assignment> }
+      @assignments_by = Hash.new { |h,k| h[k] = [] }
+      @cumulative_assignments = {}.compare_by_identity
+
+      # { Package => Package::Version }
+      @decisions = {}
+
+      # { Package => Term }
+      @terms = {}
+      @relation_cache = Hash.new { |h,k| h[k] = {} }
+
+      # { Package => Boolean }
+      @required = {}
+    end
+
+    def add_assignment(assignment)
+      term = assignment.term
+      package = term.package
+
+      @assignments << assignment
+      @assignments_by[package] << assignment
+
+      @required[package] = true if term.positive?
+
+      if @terms.key?(package)
+        old_term = @terms[package]
+        @terms[package] = old_term.intersect(term)
+      else
+        @terms[package] = term
+      end
+      @relation_cache[package].clear
+
+      @cumulative_assignments[assignment] = @terms[package]
+    end
+  end
+end
diff --git a/lib/bundler/vendor/pub_grub/lib/pub_grub/rubygems.rb b/lib/bundler/vendor/pub_grub/lib/pub_grub/rubygems.rb
new file mode 100644
index 0000000000..245c23be22
--- /dev/null
+++ b/lib/bundler/vendor/pub_grub/lib/pub_grub/rubygems.rb
@@ -0,0 +1,45 @@
+module Bundler::PubGrub
+  module RubyGems
+    extend self
+
+    def requirement_to_range(requirement)
+      ranges = requirement.requirements.map do |(op, ver)|
+        case op
+        when "~>"
+          name = "~> #{ver}"
+          bump = ver.class.new(ver.bump.to_s + ".A")
+          VersionRange.new(name: name, min: ver, max: bump, include_min: true)
+        when ">"
+          VersionRange.new(min: ver)
+        when ">="
+          VersionRange.new(min: ver, include_min: true)
+        when "<"
+          VersionRange.new(max: ver)
+        when "<="
+          VersionRange.new(max: ver, include_max: true)
+        when "="
+          VersionRange.new(min: ver, max: ver, include_min: true, include_max: true)
+        when "!="
+          VersionRange.new(min: ver, max: ver, include_min: true, include_max: true).invert
+        else
+          raise "bad version specifier: #{op}"
+        end
+      end
+
+      ranges.inject(&:intersect)
+    end
+
+    def requirement_to_constraint(package, requirement)
+      Bundler::PubGrub::VersionConstraint.new(package, range: requirement_to_range(requirement))
+    end
+
+    def parse_range(dep)
+      requirement_to_range(Gem::Requirement.new(dep))
+    end
+
+    def parse_constraint(package, dep)
+      range = parse_range(dep)
+      Bundler::PubGrub::VersionConstraint.new(package, range: range)
+    end
+  end
+end
diff --git a/lib/bundler/vendor/pub_grub/lib/pub_grub/solve_failure.rb b/lib/bundler/vendor/pub_grub/lib/pub_grub/solve_failure.rb
new file mode 100644
index 0000000000..961a7a7c0c
--- /dev/null
+++ b/lib/bundler/vendor/pub_grub/lib/pub_grub/solve_failure.rb
@@ -0,0 +1,19 @@
+require_relative 'failure_writer'
+
+module Bundler::PubGrub
+  class SolveFailure < StandardError
+    attr_reader :incompatibility
+
+    def initialize(incompatibility)
+      @incompatibility = incompatibility
+    end
+
+    def to_s
+      "Could not find compatible versions\n\n#{explanation}"
+    end
+
+    def explanation
+      @explanation ||= FailureWriter.new(@incompatibility).write
+    end
+  end
+end
diff --git a/lib/bundler/vendor/pub_grub/lib/pub_grub/static_package_source.rb b/lib/bundler/vendor/pub_grub/lib/pub_grub/static_package_source.rb
new file mode 100644
index 0000000000..4bf61461b2
--- /dev/null
+++ b/lib/bundler/vendor/pub_grub/lib/pub_grub/static_package_source.rb
@@ -0,0 +1,60 @@
+require_relative 'package'
+require_relative 'version_constraint'
+require_relative 'incompatibility'
+require_relative 'basic_package_source'
+
+module Bundler::PubGrub
+  class StaticPackageSource < BasicPackageSource
+    class DSL
+      def initialize(packages, root_deps)
+        @packages = packages
+        @root_deps = root_deps
+      end
+
+      def root(deps:)
+        @root_deps.update(deps)
+      end
+
+      def add(name, version, deps: {})
+        version = Gem::Version.new(version)
+        @packages[name] ||= {}
+        raise ArgumentError, "#{name} #{version} declared twice" if @packages[name].key?(version)
+        @packages[name][version] = clean_deps(name, version, deps)
+      end
+
+      private
+
+      # Exclude redundant self-referencing dependencies
+      def clean_deps(name, version, deps)
+        deps.reject {|dep_name, req| name == dep_name && Bundler::PubGrub::RubyGems.parse_range(req).include?(version) }
+      end
+    end
+
+    def initialize
+      @root_deps = {}
+      @packages = {}
+
+      yield DSL.new(@packages, @root_deps)
+
+      super()
+    end
+
+    def all_versions_for(package)
+      @packages[package].keys
+    end
+
+    def root_dependencies
+      @root_deps
+    end
+
+    def dependencies_for(package, version)
+      @packages[package][version]
+    end
+
+    def parse_dependency(package, dependency)
+      return false unless @packages.key?(package)
+
+      Bundler::PubGrub::RubyGems.parse_constraint(package, dependency)
+    end
+  end
+end
diff --git a/lib/bundler/vendor/pub_grub/lib/pub_grub/term.rb b/lib/bundler/vendor/pub_grub/lib/pub_grub/term.rb
new file mode 100644
index 0000000000..1d0f763378
--- /dev/null
+++ b/lib/bundler/vendor/pub_grub/lib/pub_grub/term.rb
@@ -0,0 +1,105 @@
+module Bundler::PubGrub
+  class Term
+    attr_reader :package, :constraint, :positive
+
+    def initialize(constraint, positive)
+      @constraint = constraint
+      @package = @constraint.package
+      @positive = positive
+    end
+
+    def to_s(allow_every: false)
+      if positive
+        @constraint.to_s(allow_every: allow_every)
+      else
+        "not #{@constraint}"
+      end
+    end
+
+    def hash
+      constraint.hash ^ positive.hash
+    end
+
+    def eql?(other)
+      positive == other.positive &&
+        constraint.eql?(other.constraint)
+    end
+
+    def invert
+      self.class.new(@constraint, !@positive)
+    end
+    alias_method :inverse, :invert
+
+    def intersect(other)
+      raise ArgumentError, "packages must match" if package != other.package
+
+      if positive? && other.positive?
+        self.class.new(constraint.intersect(other.constraint), true)
+      elsif negative? && other.negative?
+        self.class.new(constraint.union(other.constraint), false)
+      else
+        positive = positive? ? self : other
+        negative = negative? ? self : other
+        self.class.new(positive.constraint.intersect(negative.constraint.invert), true)
+      end
+    end
+
+    def difference(other)
+      intersect(other.invert)
+    end
+
+    def relation(other)
+      if positive? && other.positive?
+        constraint.relation(other.constraint)
+      elsif negative? && other.positive?
+        if constraint.allows_all?(other.constraint)
+          :disjoint
+        else
+          :overlap
+        end
+      elsif positive? && other.negative?
+        if !other.constraint.allows_any?(constraint)
+          :subset
+        elsif other.constraint.allows_all?(constraint)
+          :disjoint
+        else
+          :overlap
+        end
+      elsif negative? && other.negative?
+        if constraint.allows_all?(other.constraint)
+          :subset
+        else
+          :overlap
+        end
+      else
+        raise
+      end
+    end
+
+    def normalized_constraint
+      @normalized_constraint ||= positive ? constraint : constraint.invert
+    end
+
+    def satisfies?(other)
+      raise ArgumentError, "packages must match" unless package == other.package
+
+      relation(other) == :subset
+    end
+
+    def positive?
+      @positive
+    end
+
+    def negative?
+      !positive?
+    end
+
+    def empty?
+      @empty ||= normalized_constraint.empty?
+    end
+
+    def inspect
+      "#<#{self.class} #{self}>"
+    end
+  end
+end
diff --git a/lib/bundler/vendor/pub_grub/lib/pub_grub/version.rb b/lib/bundler/vendor/pub_grub/lib/pub_grub/version.rb
new file mode 100644
index 0000000000..d7984b3863
--- /dev/null
+++ b/lib/bundler/vendor/pub_grub/lib/pub_grub/version.rb
@@ -0,0 +1,3 @@
+module Bundler::PubGrub
+  VERSION = "0.5.0"
+end
diff --git a/lib/bundler/vendor/pub_grub/lib/pub_grub/version_constraint.rb b/lib/bundler/vendor/pub_grub/lib/pub_grub/version_constraint.rb
new file mode 100644
index 0000000000..b71f3eaf53
--- /dev/null
+++ b/lib/bundler/vendor/pub_grub/lib/pub_grub/version_constraint.rb
@@ -0,0 +1,129 @@
+require_relative 'version_range'
+
+module Bundler::PubGrub
+  class VersionConstraint
+    attr_reader :package, :range
+
+    # @param package [Bundler::PubGrub::Package]
+    # @param range [Bundler::PubGrub::VersionRange]
+    def initialize(package, range: nil)
+      @package = package
+      @range = range
+    end
+
+    def hash
+      package.hash ^ range.hash
+    end
+
+    def ==(other)
+      package == other.package &&
+        range == other.range
+    end
+
+    def eql?(other)
+      package.eql?(other.package) &&
+        range.eql?(other.range)
+    end
+
+    class << self
+      def exact(package, version)
+        range = VersionRange.new(min: version, max: version, include_min: true, include_max: true)
+        new(package, range: range)
+      end
+
+      def any(package)
+        new(package, range: VersionRange.any)
+      end
+
+      def empty(package)
+        new(package, range: VersionRange.empty)
+      end
+    end
+
+    def intersect(other)
+      unless package == other.package
+        raise ArgumentError, "Can only intersect between VersionConstraint of the same package"
+      end
+
+      self.class.new(package, range: range.intersect(other.range))
+    end
+
+    def union(other)
+      unless package == other.package
+        raise ArgumentError, "Can only intersect between VersionConstraint of the same package"
+      end
+
+      self.class.new(package, range: range.union(other.range))
+    end
+
+    def invert
+      new_range = range.invert
+      self.class.new(package, range: new_range)
+    end
+
+    def difference(other)
+      intersect(other.invert)
+    end
+
+    def allows_all?(other)
+      range.allows_all?(other.range)
+    end
+
+    def allows_any?(other)
+      range.intersects?(other.range)
+    end
+
+    def subset?(other)
+      other.allows_all?(self)
+    end
+
+    def overlap?(other)
+      other.allows_any?(self)
+    end
+
+    def disjoint?(other)
+      !overlap?(other)
+    end
+
+    def relation(other)
+      if subset?(other)
+        :subset
+      elsif overlap?(other)
+        :overlap
+      else
+        :disjoint
+      end
+    end
+
+    def to_s(allow_every: false)
+      if Package.root?(package)
+        package.to_s
+      elsif allow_every && any?
+        "every version of #{package}"
+      else
+        "#{package} #{constraint_string}"
+      end
+    end
+
+    def constraint_string
+      if any?
+        ">= 0"
+      else
+        range.to_s
+      end
+    end
+
+    def empty?
+      range.empty?
+    end
+
+    # Does this match every version of the package
+    def any?
+      range.any?
+    end
+
+    def inspect
+      "#<#{self.class} #{self}>"
+    end
+  end
+end
diff --git a/lib/bundler/vendor/pub_grub/lib/pub_grub/version_range.rb b/lib/bundler/vendor/pub_grub/lib/pub_grub/version_range.rb
new file mode 100644
index 0000000000..8d73c3f7b5
--- /dev/null
+++ b/lib/bundler/vendor/pub_grub/lib/pub_grub/version_range.rb
@@ -0,0 +1,411 @@
+# frozen_string_literal: true
+
+module Bundler::PubGrub
+  class VersionRange
+    attr_reader :min, :max, :include_min, :include_max
+
+    alias_method :include_min?, :include_min
+    alias_method :include_max?, :include_max
+
+    class Empty < VersionRange
+      undef_method :min, :max
+      undef_method :include_min, :include_min?
+      undef_method :include_max, :include_max?
+
+      def initialize
+      end
+
+      def empty?
+        true
+      end
+
+      def eql?(other)
+        other.empty?
+      end
+
+      def hash
+        [].hash
+      end
+
+      def intersects?(_)
+        false
+      end
+
+      def intersect(other)
+        self
+      end
+
+      def allows_all?(other)
+        other.empty?
+      end
+
+      def include?(_)
+        false
+      end
+
+      def any?
+        false
+      end
+
+      def to_s
+        "(no versions)"
+      end
+
+      def ==(other)
+        other.class == self.class
+      end
+
+      def invert
+        VersionRange.any
+      end
+
+      def select_versions(_)
+        []
+      end
+    end
+
+    EMPTY = Empty.new
+    Empty.singleton_class.undef_method(:new)
+
+    def self.empty
+      EMPTY
+    end
+
+    def self.any
+      new
+    end
+
+    def initialize(min: nil, max: nil, include_min: false, include_max: false, name: nil)
+      @min = min
+      @max = max
+      @include_min = include_min
+      @include_max = include_max
+      @name = name
+    end
+
+    def hash
+      @hash ||= min.hash ^ max.hash ^ include_min.hash ^ include_max.hash
+    end
+
+    def eql?(other)
+      if other.is_a?(VersionRange)
+        !other.empty? &&
+          min.eql?(other.min) &&
+          max.eql?(other.max) &&
+          include_min.eql?(other.include_min) &&
+          include_max.eql?(other.include_max)
+      else
+        ranges.eql?(other.ranges)
+      end
+    end
+
+    def ranges
+      [self]
+    end
+
+    def include?(version)
+      compare_version(version) == 0
+    end
+
+    # Partitions passed versions into [lower, within, higher]
+    #
+    # versions must be sorted
+    def partition_versions(versions)
+      min_index =
+        if !min || versions.empty?
+          0
+        elsif include_min?
+          (0..versions.size).bsearch { |i| versions[i].nil? || versions[i] >= min }
+        else
+          (0..versions.size).bsearch { |i| versions[i].nil? || versions[i] > min }
+        end
+
+      lower = versions.slice(0, min_index)
+      versions = versions.slice(min_index, versions.size)
+
+      max_index =
+        if !max || versions.empty?
+          versions.size
+        elsif include_max?
+          (0..versions.size).bsearch { |i| versions[i].nil? || versions[i] > max }
+        else
+          (0..versions.size).bsearch { |i| versions[i].nil? || versions[i] >= max }
+        end
+
+      [
+        lower,
+        versions.slice(0, max_index),
+        versions.slice(max_index, versions.size)
+      ]
+    end
+
+    # Returns versions which are included by this range.
+    #
+    # versions must be sorted
+    def select_versions(versions)
+      return versions if any?
+
+      partition_versions(versions)[1]
+    end
+
+    def compare_version(version)
+      if min
+        case version <=> min
+        when -1
+          return -1
+        when 0
+          return -1 if !include_min
+        when 1
+        end
+      end
+
+      if max
+        case version <=> max
+        when -1
+        when 0
+          return 1 if !include_max
+        when 1
+          return 1
+        end
+      end
+
+      0
+    end
+
+    def strictly_lower?(other)
+      return false if !max || !other.min
+
+      case max <=> other.min
+      when 0
+        !include_max || !other.include_min
+      when -1
+        true
+      when 1
+        false
+      end
+    end
+
+    def strictly_higher?(other)
+      other.strictly_lower?(self)
+    end
+
+    def intersects?(other)
+      return false if other.empty?
+      return other.intersects?(self) if other.is_a?(VersionUnion)
+      !strictly_lower?(other) && !strictly_higher?(other)
+    end
+    alias_method :allows_any?, :intersects?
+
+    def intersect(other)
+      return other if other.empty?
+      return other.intersect(self) if other.is_a?(VersionUnion)
+
+      min_range =
+        if !min
+          other
+        elsif !other.min
+          self
+        else
+          case min <=> other.min
+          when 0
+            include_min ? other : self
+          when -1
+            other
+          when 1
+            self
+          end
+        end
+
+      max_range =
+        if !max
+          other
+        elsif !other.max
+          self
+        else
+          case max <=> other.max
+          when 0
+            include_max ? other : self
+          when -1
+            self
+          when 1
+            other
+          end
+        end
+
+      if !min_range.equal?(max_range) && min_range.min && max_range.max
+        case min_range.min <=> max_range.max
+        when -1
+        when 0
+          if !min_range.include_min || !max_range.include_max
+            return EMPTY
+          end
+        when 1
+          return EMPTY
+        end
+      end
+
+      VersionRange.new(
+        min: min_range.min,
+        include_min: min_range.include_min,
+        max: max_range.max,
+        include_max: max_range.include_max
+      )
+    end
+
+    # The span covered by two ranges
+    #
+    # If self and other are contiguous, this builds a union of the two ranges.
+    # (if they aren't you are probably calling the wrong method)
+    def span(other)
+      return self if other.empty?
+
+      min_range =
+        if !min
+          self
+        elsif !other.min
+          other
+        else
+          case min <=> other.min
+          when 0
+            include_min ? self : other
+          when -1
+            self
+          when 1
+            other
+          end
+        end
+
+      max_range =
+        if !max
+          self
+        elsif !other.max
+          other
+        else
+          case max <=> other.max
+          when 0
+            include_max ? self : other
+          when -1
+            other
+          when 1
+            self
+          end
+        end
+
+      VersionRange.new(
+        min: min_range.min,
+        include_min: min_range.include_min,
+        max: max_range.max,
+        include_max: max_range.include_max
+      )
+    end
+
+    def union(other)
+      return other.union(self) if other.is_a?(VersionUnion)
+
+      if contiguous_to?(other)
+        span(other)
+      else
+        VersionUnion.union([self, other])
+      end
+    end
+
+    def contiguous_to?(other)
+      return false if other.empty?
+
+      intersects?(other) ||
+        (min == other.max && (include_min || other.include_max)) ||
+        (max == other.min && (include_max || other.include_min))
+    end
+
+    def allows_all?(other)
+      return true if other.empty?
+
+      if other.is_a?(VersionUnion)
+        return VersionUnion.new([self]).allows_all?(other)
+      end
+
+      return false if max && !other.max
+      return false if min && !other.min
+
+      if min
+        case min <=> other.min
+        when -1
+        when 0
+          return false if !include_min && other.include_min
+        when 1
+          return false
+        end
+      end
+
+      if max
+        case max <=> other.max
+        when -1
+          return false
+        when 0
+          return false if !include_max && other.include_max
+        when 1
+        end
+      end
+
+      true
+    end
+
+    def any?
+      !min && !max
+    end
+
+    def empty?
+      false
+    end
+
+    def to_s
+      @name ||= constraints.join(", ")
+    end
+
+    def inspect
+      "#<#{self.class} #{to_s}>"
+    end
+
+    def upper_invert
+      return self.class.empty unless max
+
+      VersionRange.new(min: max, include_min: !include_max)
+    end
+
+    def invert
+      return self.class.empty if any?
+
+      low = VersionRange.new(max: min, include_max: !include_min)
+      high = VersionRange.new(min: max, include_min: !include_max)
+
+      if !min
+        high
+      elsif !max
+        low
+      else
+        low.union(high)
+      end
+    end
+
+    def ==(other)
+      self.class == other.class &&
+        min == other.min &&
+        max == other.max &&
+        include_min == other.include_min &&
+        include_max == other.include_max
+    end
+
+    private
+
+    def constraints
+      return ["any"] if any?
+      return ["= #{min}"] if min.to_s == max.to_s
+
+      c = []
+      c << "#{include_min ? ">=" : ">"} #{min}" if min
+      c << "#{include_max ? "<=" : "<"} #{max}" if max
+      c
+    end
+
+  end
+end
diff --git a/lib/bundler/vendor/pub_grub/lib/pub_grub/version_solver.rb b/lib/bundler/vendor/pub_grub/lib/pub_grub/version_solver.rb
new file mode 100644
index 0000000000..4caf6b355b
--- /dev/null
+++ b/lib/bundler/vendor/pub_grub/lib/pub_grub/version_solver.rb
@@ -0,0 +1,248 @@
+require_relative 'partial_solution'
+require_relative 'term'
+require_relative 'incompatibility'
+require_relative 'solve_failure'
+
+module Bundler::PubGrub
+  class VersionSolver
+    attr_reader :logger
+    attr_reader :source
+    attr_reader :solution
+
+    def initialize(source:, root: Package.root, logger: Bundler::PubGrub.logger)
+      @logger = logger
+
+      @source = source
+
+      # { package => [incompatibility, ...]}
+      @incompatibilities = Hash.new do |h, k|
+        h[k] = []
+      end
+
+      @seen_incompatibilities = {}
+
+      @solution = PartialSolution.new
+
+      add_incompatibility Incompatibility.new([
+        Term.new(VersionConstraint.any(root), false)
+      ], cause: :root)
+
+      propagate(root)
+    end
+
+    def solved?
+      solution.unsatisfied.empty?
+    end
+
+    # Returns true if there is more work to be done, false otherwise
+    def work
+      return false if solved?
+
+      next_package = choose_package_version
+      propagate(next_package)
+
+      if solved?
+        logger.info { "Solution found after #{solution.attempted_solutions} attempts:" }
+        solution.decisions.each do |package, version|
+          next if Package.root?(package)
+          logger.info { "* #{package} #{version}" }
+        end
+
+        false
+      else
+        true
+      end
+    end
+
+    def solve
+      work until solved?
+
+      solution.decisions
+    end
+
+    alias_method :result, :solve
+
+    private
+
+    def propagate(initial_package)
+      changed = [initial_package]
+      while package = changed.shift
+        @incompatibilities[package].reverse_each do |incompatibility|
+          result = propagate_incompatibility(incompatibility)
+          if result == :conflict
+            root_cause = resolve_conflict(incompatibility)
+            changed.clear
+            changed << propagate_incompatibility(root_cause)
+          elsif result # should be a Package
+            changed << result
+          end
+        end
+        changed.uniq!
+      end
+    end
+
+    def propagate_incompatibility(incompatibility)
+      unsatisfied = nil
+      incompatibility.terms.each do |term|
+        relation = solution.relation(term)
+        if relation == :disjoint
+          return nil
+        elsif relation == :overlap
+          # If more than one term is inconclusive, we can't deduce anything
+          return nil if unsatisfied
+          unsatisfied = term
+        end
+      end
+
+      if !unsatisfied
+        return :conflict
+      end
+
+      logger.debug { "derived: #{unsatisfied.invert}" }
+
+      solution.derive(unsatisfied.invert, incompatibility)
+
+      unsatisfied.package
+    end
+
+    def next_package_to_try
+      solution.unsatisfied.min_by do |term|
+        package = term.package
+        range = term.constraint.range
+        matching_versions = source.versions_for(package, range)
+        higher_versions = source.versions_for(package, range.upper_invert)
+
+        [matching_versions.count <= 1 ? 0 : 1, higher_versions.count]
+      end.package
+    end
+
+    def choose_package_version
+      if solution.unsatisfied.empty?
+        logger.info "No packages unsatisfied. Solving complete!"
+        return nil
+      end
+
+      package = next_package_to_try
+      unsatisfied_term = solution.unsatisfied.find { |t| t.package == package }
+      version = source.versions_for(package, unsatisfied_term.constraint.range).first
+      logger.debug { "attempting #{package} #{version}" }
+
+      if version.nil?
+        add_incompatibility source.no_versions_incompatibility_for(package, unsatisfied_term)
+        return package
+      end
+
+      conflict = false
+
+      source.incompatibilities_for(package, version).each do |incompatibility|
+        if @seen_incompatibilities.include?(incompatibility)
+          logger.debug { "knew: #{incompatibility}" }
+          next
+        end
+        @seen_incompatibilities[incompatibility] = true
+
+        add_incompatibility incompatibility
+
+        conflict ||= incompatibility.terms.all? do |term|
+          term.package == package || solution.satisfies?(term)
+        end
+      end
+
+      unless conflict
+        logger.info { "selected #{package} #{version}" }
+
+        solution.decide(package, version)
+      else
+        logger.info { "conflict: #{conflict.inspect}" }
+      end
+
+      package
+    end
+
+    def resolve_conflict(incompatibility)
+      logger.info { "conflict: #{incompatibility}" }
+
+      new_incompatibility = nil
+
+      while !incompatibility.failure?
+        most_recent_term = nil
+        most_recent_satisfier = nil
+        difference = nil
+
+        previous_level = 1
+
+        incompatibility.terms.each do |term|
+          satisfier = solution.satisfier(term)
+
+          if most_recent_satisfier.nil?
+            most_recent_term = term
+            most_recent_satisfier = satisfier
+          elsif most_recent_satisfier.index < satisfier.index
+            previous_level = [previous_level, most_recent_satisfier.decision_level].max
+            most_recent_term = term
+            most_recent_satisfier = satisfier
+            difference = nil
+          else
+            previous_level = [previous_level, satisfier.decision_level].max
+          end
+
+          if most_recent_term == term
+            difference = most_recent_satisfier.term.difference(most_recent_term)
+            if difference.empty?
+              difference = nil
+            else
+              difference_satisfier = solution.satisfier(difference.inverse)
+              previous_level = [previous_level, difference_satisfier.decision_level].max
+            end
+          end
+        end
+
+        if previous_level < most_recent_satisfier.decision_level ||
+            most_recent_satisfier.decision?
+
+          logger.info { "backtracking to #{previous_level}" }
+          solution.backtrack(previous_level)
+
+          if new_incompatibility
+            add_incompatibility(new_incompatibility)
+          end
+
+          return incompatibility
+        end
+
+        new_terms = []
+        new_terms += incompatibility.terms - [most_recent_term]
+        new_terms += most_recent_satisfier.cause.terms.reject { |term|
+          term.package == most_recent_satisfier.term.package
+        }
+        if difference
+          new_terms << difference.invert
+        end
+
+        new_incompatibility = Incompatibility.new(new_terms, cause: Incompatibility::ConflictCause.new(incompatibility, most_recent_satisfier.cause))
+
+        if incompatibility.to_s == new_incompatibility.to_s
+          logger.info { "!! failed to resolve conflicts, this shouldn't have happened" }
+          break
+        end
+
+        incompatibility = new_incompatibility
+
+        partially = difference ? " partially" : ""
+        logger.info { "! #{most_recent_term} is#{partially} satisfied by #{most_recent_satisfier.term}" }
+        logger.info { "! which is caused by #{most_recent_satisfier.cause}" }
+        logger.info { "! thus #{incompatibility}" }
+      end
+
+      raise SolveFailure.new(incompatibility)
+    end
+
+    def add_incompatibility(incompatibility)
+      logger.debug { "fact: #{incompatibility}" }
+      incompatibility.terms.each do |term|
+        package = term.package
+        @incompatibilities[package] << incompatibility
+      end
+    end
+  end
+end
diff --git a/lib/bundler/vendor/pub_grub/lib/pub_grub/version_union.rb b/lib/bundler/vendor/pub_grub/lib/pub_grub/version_union.rb
new file mode 100644
index 0000000000..bbc10c3804
--- /dev/null
+++ b/lib/bundler/vendor/pub_grub/lib/pub_grub/version_union.rb
@@ -0,0 +1,178 @@
+# frozen_string_literal: true
+
+module Bundler::PubGrub
+  class VersionUnion
+    attr_reader :ranges
+
+    def self.normalize_ranges(ranges)
+      ranges = ranges.flat_map do |range|
+        range.ranges
+      end
+
+      ranges.reject!(&:empty?)
+
+      return [] if ranges.empty?
+
+      mins, ranges = ranges.partition { |r| !r.min }
+      original_ranges = mins + ranges.sort_by { |r| [r.min, r.include_min ? 0 : 1] }
+      ranges = [original_ranges.shift]
+      original_ranges.each do |range|
+        if ranges.last.contiguous_to?(range)
+          ranges << ranges.pop.span(range)
+        else
+          ranges << range
+        end
+      end
+
+      ranges
+    end
+
+    def self.union(ranges, normalize: true)
+      ranges = normalize_ranges(ranges) if normalize
+
+      if ranges.size == 0
+        VersionRange.empty
+      elsif ranges.size == 1
+        ranges[0]
+      else
+        new(ranges)
+      end
+    end
+
+    def initialize(ranges)
+      raise ArgumentError unless ranges.all? { |r| r.instance_of?(VersionRange) }
+      @ranges = ranges
+    end
+
+    def hash
+      ranges.hash
+    end
+
+    def eql?(other)
+      ranges.eql?(other.ranges)
+    end
+
+    def include?(version)
+      !!ranges.bsearch {|r| r.compare_version(version) }
+    end
+
+    def select_versions(all_versions)
+      versions = []
+      ranges.inject(all_versions) do |acc, range|
+        _, matching, higher = range.partition_versions(acc)
+        versions.concat matching
+        higher
+      end
+      versions
+    end
+
+    def intersects?(other)
+      my_ranges = ranges.dup
+      other_ranges = other.ranges.dup
+
+      my_range = my_ranges.shift
+      other_range = other_ranges.shift
+      while my_range && other_range
+        if my_range.intersects?(other_range)
+          return true
+        end
+
+        if !my_range.max || other_range.empty? || (other_range.max && other_range.max < my_range.max)
+          other_range = other_ranges.shift
+        else
+          my_range = my_ranges.shift
+        end
+      end
+    end
+    alias_method :allows_any?, :intersects?
+
+    def allows_all?(other)
+      my_ranges = ranges.dup
+
+      my_range = my_ranges.shift
+
+      other.ranges.all? do |other_range|
+        while my_range
+          break if my_range.allows_all?(other_range)
+          my_range = my_ranges.shift
+        end
+
+        !!my_range
+      end
+    end
+
+    def empty?
+      false
+    end
+
+    def any?
+      false
+    end
+
+    def intersect(other)
+      my_ranges = ranges.dup
+      other_ranges = other.ranges.dup
+      new_ranges = []
+
+      my_range = my_ranges.shift
+      other_range = other_ranges.shift
+      while my_range && other_range
+        new_ranges << my_range.intersect(other_range)
+
+        if !my_range.max || other_range.empty? || (other_range.max && other_range.max < my_range.max)
+          other_range = other_ranges.shift
+        else
+          my_range = my_ranges.shift
+        end
+      end
+      new_ranges.reject!(&:empty?)
+      VersionUnion.union(new_ranges, normalize: false)
+    end
+
+    def upper_invert
+      ranges.last.upper_invert
+    end
+
+    def invert
+      ranges.map(&:invert).inject(:intersect)
+    end
+
+    def union(other)
+      VersionUnion.union([self, other])
+    end
+
+    def to_s
+      output = []
+
+      ranges = self.ranges.dup
+      while !ranges.empty?
+        ne = []
+        range = ranges.shift
+        while !ranges.empty? && ranges[0].min.to_s == range.max.to_s
+          ne << range.max
+          range = range.span(ranges.shift)
+        end
+
+        ne.map! {|x| "!= #{x}" }
+        if ne.empty?
+          output << range.to_s
+        elsif range.any?
+          output << ne.join(', ')
+        else
+          output << "#{range}, #{ne.join(', ')}"
+        end
+      end
+
+      output.join(" OR ")
+    end
+
+    def inspect
+      "#<#{self.class} #{to_s}>"
+    end
+
+    def ==(other)
+      self.class == other.class &&
+        self.ranges == other.ranges
+    end
+  end
+end
diff --git a/lib/bundler/vendor/thor/lib/thor/shell/basic.rb b/lib/bundler/vendor/thor/lib/thor/shell/basic.rb
index 8eff00bf3d..ef97d52ae7 100644
--- a/lib/bundler/vendor/thor/lib/thor/shell/basic.rb
+++ b/lib/bundler/vendor/thor/lib/thor/shell/basic.rb
@@ -425,7 +425,7 @@ class Bundler::Thor
       end
 
       def unix?
-        RUBY_PLATFORM =~ /(aix|darwin|linux|(net|free|open)bsd|cygwin|solaris|irix|hpux)/i
+        RUBY_PLATFORM =~ /(aix|darwin|linux|(net|free|open)bsd|cygwin|solaris)/i
       end
 
       def truncate(string, width)
diff --git a/lib/bundler/vendor/tmpdir/lib/tmpdir.rb b/lib/bundler/vendor/tmpdir/lib/tmpdir.rb
deleted file mode 100644
index 70d43e0c6b..0000000000
--- a/lib/bundler/vendor/tmpdir/lib/tmpdir.rb
+++ /dev/null
@@ -1,154 +0,0 @@
-# frozen_string_literal: true
-#
-# tmpdir - retrieve temporary directory path
-#
-# $Id$
-#
-
-require_relative '../../fileutils/lib/fileutils'
-begin
-  require 'etc.so'
-rescue LoadError # rescue LoadError for miniruby
-end
-
-class Bundler::Dir < Dir
-
-  @systmpdir ||= defined?(Etc.systmpdir) ? Etc.systmpdir : '/tmp'
-
-  ##
-  # Returns the operating system's temporary file path.
-
-  def self.tmpdir
-    tmp = nil
-    ['TMPDIR', 'TMP', 'TEMP', ['system temporary path', @systmpdir], ['/tmp']*2, ['.']*2].each do |name, dir = ENV[name]|
-      next if !dir
-      dir = File.expand_path(dir)
-      stat = File.stat(dir) rescue next
-      case
-      when !stat.directory?
-        warn "#{name} is not a directory: #{dir}"
-      when !stat.writable?
-        warn "#{name} is not writable: #{dir}"
-      when stat.world_writable? && !stat.sticky?
-        warn "#{name} is world-writable: #{dir}"
-      else
-        tmp = dir
-        break
-      end
-    end
-    raise ArgumentError, "could not find a temporary directory" unless tmp
-    tmp
-  end
-
-  # Bundler::Dir.mktmpdir creates a temporary directory.
-  #
-  # The directory is created with 0700 permission.
-  # Application should not change the permission to make the temporary directory accessible from other users.
-  #
-  # The prefix and suffix of the name of the directory is specified by
-  # the optional first argument, <i>prefix_suffix</i>.
-  # - If it is not specified or nil, "d" is used as the prefix and no suffix is used.
-  # - If it is a string, it is used as the prefix and no suffix is used.
-  # - If it is an array, first element is used as the prefix and second element is used as a suffix.
-  #
-  #  Bundler::Dir.mktmpdir {|dir| dir is ".../d..." }
-  #  Bundler::Dir.mktmpdir("foo") {|dir| dir is ".../foo..." }
-  #  Bundler::Dir.mktmpdir(["foo", "bar"]) {|dir| dir is ".../foo...bar" }
-  #
-  # The directory is created under Bundler::Dir.tmpdir or
-  # the optional second argument <i>tmpdir</i> if non-nil value is given.
-  #
-  #  Bundler::Dir.mktmpdir {|dir| dir is "#{Bundler::Dir.tmpdir}/d..." }
-  #  Bundler::Dir.mktmpdir(nil, "/var/tmp") {|dir| dir is "/var/tmp/d..." }
-  #
-  # If a block is given,
-  # it is yielded with the path of the directory.
-  # The directory and its contents are removed
-  # using Bundler::FileUtils.remove_entry before Bundler::Dir.mktmpdir returns.
-  # The value of the block is returned.
-  #
-  #  Bundler::Dir.mktmpdir {|dir|
-  #    # use the directory...
-  #    open("#{dir}/foo", "w") { ... }
-  #  }
-  #
-  # If a block is not given,
-  # The path of the directory is returned.
-  # In this case, Bundler::Dir.mktmpdir doesn't remove the directory.
-  #
-  #  dir = Bundler::Dir.mktmpdir
-  #  begin
-  #    # use the directory...
-  #    open("#{dir}/foo", "w") { ... }
-  #  ensure
-  #    # remove the directory.
-  #    Bundler::FileUtils.remove_entry dir
-  #  end
-  #
-  def self.mktmpdir(prefix_suffix=nil, *rest, **options)
-    base = nil
-    path = Tmpname.create(prefix_suffix || "d", *rest, **options) {|p, _, _, d|
-      base = d
-      mkdir(p, 0700)
-    }
-    if block_given?
-      begin
-        yield path.dup
-      ensure
-        unless base
-          stat = File.stat(File.dirname(path))
-          if stat.world_writable? and !stat.sticky?
-            raise ArgumentError, "parent directory is world writable but not sticky"
-          end
-        end
-        Bundler::FileUtils.remove_entry path
-      end
-    else
-      path
-    end
-  end
-
-  module Tmpname # :nodoc:
-    module_function
-
-    def tmpdir
-      Bundler::Dir.tmpdir
-    end
-
-    UNUSABLE_CHARS = "^,-.0-9A-Z_a-z~"
-
-    class << (RANDOM = Random.new)
-      MAX = 36**6 # < 0x100000000
-      def next
-        rand(MAX).to_s(36)
-      end
-    end
-    private_constant :RANDOM
-
-    def create(basename, tmpdir=nil, max_try: nil, **opts)
-      origdir = tmpdir
-      tmpdir ||= tmpdir()
-      n = nil
-      prefix, suffix = basename
-      prefix = (String.try_convert(prefix) or
-                raise ArgumentError, "unexpected prefix: #{prefix.inspect}")
-      prefix = prefix.delete(UNUSABLE_CHARS)
-      suffix &&= (String.try_convert(suffix) or
-                  raise ArgumentError, "unexpected suffix: #{suffix.inspect}")
-      suffix &&= suffix.delete(UNUSABLE_CHARS)
-      begin
-        t = Time.now.strftime("%Y%m%d")
-        path = "#{prefix}#{t}-#{$$}-#{RANDOM.next}"\
-               "#{n ? %[-#{n}] : ''}#{suffix||''}"
-        path = File.join(tmpdir, path)
-        yield(path, n, opts, origdir)
-      rescue Errno::EEXIST
-        n ||= 0
-        n += 1
-        retry if !max_try or n < max_try
-        raise "cannot generate temporary name using `#{basename}' under `#{tmpdir}'"
-      end
-      path
-    end
-  end
-end
diff --git a/lib/bundler/vendor/tsort/lib/tsort.rb b/lib/bundler/vendor/tsort/lib/tsort.rb
index 8454583295..4a0e1a4e25 100644
--- a/lib/bundler/vendor/tsort/lib/tsort.rb
+++ b/lib/bundler/vendor/tsort/lib/tsort.rb
@@ -6,24 +6,24 @@
 #
 
 #
-# TSort implements topological sorting using Tarjan's algorithm for
+# Bundler::TSort implements topological sorting using Tarjan's algorithm for
 # strongly connected components.
 #
-# TSort is designed to be able to be used with any object which can be
+# Bundler::TSort is designed to be able to be used with any object which can be
 # interpreted as a directed graph.
 #
-# TSort requires two methods to interpret an object as a graph,
+# Bundler::TSort requires two methods to interpret an object as a graph,
 # tsort_each_node and tsort_each_child.
 #
 # * tsort_each_node is used to iterate for all nodes over a graph.
 # * tsort_each_child is used to iterate for child nodes of a given node.
 #
 # The equality of nodes are defined by eql? and hash since
-# TSort uses Hash internally.
+# Bundler::TSort uses Hash internally.
 #
 # == A Simple Example
 #
-# The following example demonstrates how to mix the TSort module into an
+# The following example demonstrates how to mix the Bundler::TSort module into an
 # existing class (in this case, Hash). Here, we're treating each key in
 # the hash as a node in the graph, and so we simply alias the required
 # #tsort_each_node method to Hash's #each_key method. For each key in the
@@ -32,10 +32,10 @@
 # method, which fetches the array of child nodes and then iterates over that
 # array using the user-supplied block.
 #
-#   require 'tsort'
+#   require 'bundler/vendor/tsort/lib/tsort'
 #
 #   class Hash
-#     include TSort
+#     include Bundler::TSort
 #     alias tsort_each_node each_key
 #     def tsort_each_child(node, &block)
 #       fetch(node).each(&block)
@@ -52,7 +52,7 @@
 #
 # A very simple `make' like tool can be implemented as follows:
 #
-#   require 'tsort'
+#   require 'bundler/vendor/tsort/lib/tsort'
 #
 #   class Make
 #     def initialize
@@ -70,7 +70,7 @@
 #       each_strongly_connected_component_from(target) {|ns|
 #         if ns.length != 1
 #           fs = ns.delete_if {|n| Array === n}
-#           raise TSort::Cyclic.new("cyclic dependencies: #{fs.join ', '}")
+#           raise Bundler::TSort::Cyclic.new("cyclic dependencies: #{fs.join ', '}")
 #         end
 #         n = ns.first
 #         if Array === n
@@ -93,7 +93,7 @@
 #     def tsort_each_child(node, &block)
 #       @dep[node].each(&block)
 #     end
-#     include TSort
+#     include Bundler::TSort
 #   end
 #
 #   def command(arg)
@@ -120,334 +120,333 @@
 # R. E. Tarjan, "Depth First Search and Linear Graph Algorithms",
 # <em>SIAM Journal on Computing</em>, Vol. 1, No. 2, pp. 146-160, June 1972.
 #
-module Bundler
-  module TSort
-    class Cyclic < StandardError
-    end
 
-    # Returns a topologically sorted array of nodes.
-    # The array is sorted from children to parents, i.e.
-    # the first element has no child and the last node has no parent.
-    #
-    # If there is a cycle, TSort::Cyclic is raised.
-    #
-    #   class G
-    #     include TSort
-    #     def initialize(g)
-    #       @g = g
-    #     end
-    #     def tsort_each_child(n, &b) @g[n].each(&b) end
-    #     def tsort_each_node(&b) @g.each_key(&b) end
-    #   end
-    #
-    #   graph = G.new({1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]})
-    #   p graph.tsort #=> [4, 2, 3, 1]
-    #
-    #   graph = G.new({1=>[2], 2=>[3, 4], 3=>[2], 4=>[]})
-    #   p graph.tsort # raises TSort::Cyclic
-    #
-    def tsort
-      each_node = method(:tsort_each_node)
-      each_child = method(:tsort_each_child)
-      TSort.tsort(each_node, each_child)
-    end
+module Bundler::TSort
+  class Cyclic < StandardError
+  end
 
-    # Returns a topologically sorted array of nodes.
-    # The array is sorted from children to parents, i.e.
-    # the first element has no child and the last node has no parent.
-    #
-    # The graph is represented by _each_node_ and _each_child_.
-    # _each_node_ should have +call+ method which yields for each node in the graph.
-    # _each_child_ should have +call+ method which takes a node argument and yields for each child node.
-    #
-    # If there is a cycle, TSort::Cyclic is raised.
-    #
-    #   g = {1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]}
-    #   each_node = lambda {|&b| g.each_key(&b) }
-    #   each_child = lambda {|n, &b| g[n].each(&b) }
-    #   p TSort.tsort(each_node, each_child) #=> [4, 2, 3, 1]
-    #
-    #   g = {1=>[2], 2=>[3, 4], 3=>[2], 4=>[]}
-    #   each_node = lambda {|&b| g.each_key(&b) }
-    #   each_child = lambda {|n, &b| g[n].each(&b) }
-    #   p TSort.tsort(each_node, each_child) # raises TSort::Cyclic
-    #
-    def TSort.tsort(each_node, each_child)
-      TSort.tsort_each(each_node, each_child).to_a
-    end
+  # Returns a topologically sorted array of nodes.
+  # The array is sorted from children to parents, i.e.
+  # the first element has no child and the last node has no parent.
+  #
+  # If there is a cycle, Bundler::TSort::Cyclic is raised.
+  #
+  #   class G
+  #     include Bundler::TSort
+  #     def initialize(g)
+  #       @g = g
+  #     end
+  #     def tsort_each_child(n, &b) @g[n].each(&b) end
+  #     def tsort_each_node(&b) @g.each_key(&b) end
+  #   end
+  #
+  #   graph = G.new({1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]})
+  #   p graph.tsort #=> [4, 2, 3, 1]
+  #
+  #   graph = G.new({1=>[2], 2=>[3, 4], 3=>[2], 4=>[]})
+  #   p graph.tsort # raises Bundler::TSort::Cyclic
+  #
+  def tsort
+    each_node = method(:tsort_each_node)
+    each_child = method(:tsort_each_child)
+    Bundler::TSort.tsort(each_node, each_child)
+  end
 
-    # The iterator version of the #tsort method.
-    # <tt><em>obj</em>.tsort_each</tt> is similar to <tt><em>obj</em>.tsort.each</tt>, but
-    # modification of _obj_ during the iteration may lead to unexpected results.
-    #
-    # #tsort_each returns +nil+.
-    # If there is a cycle, TSort::Cyclic is raised.
-    #
-    #   class G
-    #     include TSort
-    #     def initialize(g)
-    #       @g = g
-    #     end
-    #     def tsort_each_child(n, &b) @g[n].each(&b) end
-    #     def tsort_each_node(&b) @g.each_key(&b) end
-    #   end
-    #
-    #   graph = G.new({1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]})
-    #   graph.tsort_each {|n| p n }
-    #   #=> 4
-    #   #   2
-    #   #   3
-    #   #   1
-    #
-    def tsort_each(&block) # :yields: node
-      each_node = method(:tsort_each_node)
-      each_child = method(:tsort_each_child)
-      TSort.tsort_each(each_node, each_child, &block)
-    end
+  # Returns a topologically sorted array of nodes.
+  # The array is sorted from children to parents, i.e.
+  # the first element has no child and the last node has no parent.
+  #
+  # The graph is represented by _each_node_ and _each_child_.
+  # _each_node_ should have +call+ method which yields for each node in the graph.
+  # _each_child_ should have +call+ method which takes a node argument and yields for each child node.
+  #
+  # If there is a cycle, Bundler::TSort::Cyclic is raised.
+  #
+  #   g = {1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]}
+  #   each_node = lambda {|&b| g.each_key(&b) }
+  #   each_child = lambda {|n, &b| g[n].each(&b) }
+  #   p Bundler::TSort.tsort(each_node, each_child) #=> [4, 2, 3, 1]
+  #
+  #   g = {1=>[2], 2=>[3, 4], 3=>[2], 4=>[]}
+  #   each_node = lambda {|&b| g.each_key(&b) }
+  #   each_child = lambda {|n, &b| g[n].each(&b) }
+  #   p Bundler::TSort.tsort(each_node, each_child) # raises Bundler::TSort::Cyclic
+  #
+  def self.tsort(each_node, each_child)
+    tsort_each(each_node, each_child).to_a
+  end
 
-    # The iterator version of the TSort.tsort method.
-    #
-    # The graph is represented by _each_node_ and _each_child_.
-    # _each_node_ should have +call+ method which yields for each node in the graph.
-    # _each_child_ should have +call+ method which takes a node argument and yields for each child node.
-    #
-    #   g = {1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]}
-    #   each_node = lambda {|&b| g.each_key(&b) }
-    #   each_child = lambda {|n, &b| g[n].each(&b) }
-    #   TSort.tsort_each(each_node, each_child) {|n| p n }
-    #   #=> 4
-    #   #   2
-    #   #   3
-    #   #   1
-    #
-    def TSort.tsort_each(each_node, each_child) # :yields: node
-      return to_enum(__method__, each_node, each_child) unless block_given?
+  # The iterator version of the #tsort method.
+  # <tt><em>obj</em>.tsort_each</tt> is similar to <tt><em>obj</em>.tsort.each</tt>, but
+  # modification of _obj_ during the iteration may lead to unexpected results.
+  #
+  # #tsort_each returns +nil+.
+  # If there is a cycle, Bundler::TSort::Cyclic is raised.
+  #
+  #   class G
+  #     include Bundler::TSort
+  #     def initialize(g)
+  #       @g = g
+  #     end
+  #     def tsort_each_child(n, &b) @g[n].each(&b) end
+  #     def tsort_each_node(&b) @g.each_key(&b) end
+  #   end
+  #
+  #   graph = G.new({1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]})
+  #   graph.tsort_each {|n| p n }
+  #   #=> 4
+  #   #   2
+  #   #   3
+  #   #   1
+  #
+  def tsort_each(&block) # :yields: node
+    each_node = method(:tsort_each_node)
+    each_child = method(:tsort_each_child)
+    Bundler::TSort.tsort_each(each_node, each_child, &block)
+  end
 
-      TSort.each_strongly_connected_component(each_node, each_child) {|component|
-        if component.size == 1
-          yield component.first
-        else
-          raise Cyclic.new("topological sort failed: #{component.inspect}")
-        end
-      }
-    end
+  # The iterator version of the Bundler::TSort.tsort method.
+  #
+  # The graph is represented by _each_node_ and _each_child_.
+  # _each_node_ should have +call+ method which yields for each node in the graph.
+  # _each_child_ should have +call+ method which takes a node argument and yields for each child node.
+  #
+  #   g = {1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]}
+  #   each_node = lambda {|&b| g.each_key(&b) }
+  #   each_child = lambda {|n, &b| g[n].each(&b) }
+  #   Bundler::TSort.tsort_each(each_node, each_child) {|n| p n }
+  #   #=> 4
+  #   #   2
+  #   #   3
+  #   #   1
+  #
+  def self.tsort_each(each_node, each_child) # :yields: node
+    return to_enum(__method__, each_node, each_child) unless block_given?
 
-    # Returns strongly connected components as an array of arrays of nodes.
-    # The array is sorted from children to parents.
-    # Each elements of the array represents a strongly connected component.
-    #
-    #   class G
-    #     include TSort
-    #     def initialize(g)
-    #       @g = g
-    #     end
-    #     def tsort_each_child(n, &b) @g[n].each(&b) end
-    #     def tsort_each_node(&b) @g.each_key(&b) end
-    #   end
-    #
-    #   graph = G.new({1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]})
-    #   p graph.strongly_connected_components #=> [[4], [2], [3], [1]]
-    #
-    #   graph = G.new({1=>[2], 2=>[3, 4], 3=>[2], 4=>[]})
-    #   p graph.strongly_connected_components #=> [[4], [2, 3], [1]]
-    #
-    def strongly_connected_components
-      each_node = method(:tsort_each_node)
-      each_child = method(:tsort_each_child)
-      TSort.strongly_connected_components(each_node, each_child)
-    end
+    each_strongly_connected_component(each_node, each_child) {|component|
+      if component.size == 1
+        yield component.first
+      else
+        raise Cyclic.new("topological sort failed: #{component.inspect}")
+      end
+    }
+  end
 
-    # Returns strongly connected components as an array of arrays of nodes.
-    # The array is sorted from children to parents.
-    # Each elements of the array represents a strongly connected component.
-    #
-    # The graph is represented by _each_node_ and _each_child_.
-    # _each_node_ should have +call+ method which yields for each node in the graph.
-    # _each_child_ should have +call+ method which takes a node argument and yields for each child node.
-    #
-    #   g = {1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]}
-    #   each_node = lambda {|&b| g.each_key(&b) }
-    #   each_child = lambda {|n, &b| g[n].each(&b) }
-    #   p TSort.strongly_connected_components(each_node, each_child)
-    #   #=> [[4], [2], [3], [1]]
-    #
-    #   g = {1=>[2], 2=>[3, 4], 3=>[2], 4=>[]}
-    #   each_node = lambda {|&b| g.each_key(&b) }
-    #   each_child = lambda {|n, &b| g[n].each(&b) }
-    #   p TSort.strongly_connected_components(each_node, each_child)
-    #   #=> [[4], [2, 3], [1]]
-    #
-    def TSort.strongly_connected_components(each_node, each_child)
-      TSort.each_strongly_connected_component(each_node, each_child).to_a
-    end
+  # Returns strongly connected components as an array of arrays of nodes.
+  # The array is sorted from children to parents.
+  # Each elements of the array represents a strongly connected component.
+  #
+  #   class G
+  #     include Bundler::TSort
+  #     def initialize(g)
+  #       @g = g
+  #     end
+  #     def tsort_each_child(n, &b) @g[n].each(&b) end
+  #     def tsort_each_node(&b) @g.each_key(&b) end
+  #   end
+  #
+  #   graph = G.new({1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]})
+  #   p graph.strongly_connected_components #=> [[4], [2], [3], [1]]
+  #
+  #   graph = G.new({1=>[2], 2=>[3, 4], 3=>[2], 4=>[]})
+  #   p graph.strongly_connected_components #=> [[4], [2, 3], [1]]
+  #
+  def strongly_connected_components
+    each_node = method(:tsort_each_node)
+    each_child = method(:tsort_each_child)
+    Bundler::TSort.strongly_connected_components(each_node, each_child)
+  end
 
-    # The iterator version of the #strongly_connected_components method.
-    # <tt><em>obj</em>.each_strongly_connected_component</tt> is similar to
-    # <tt><em>obj</em>.strongly_connected_components.each</tt>, but
-    # modification of _obj_ during the iteration may lead to unexpected results.
-    #
-    # #each_strongly_connected_component returns +nil+.
-    #
-    #   class G
-    #     include TSort
-    #     def initialize(g)
-    #       @g = g
-    #     end
-    #     def tsort_each_child(n, &b) @g[n].each(&b) end
-    #     def tsort_each_node(&b) @g.each_key(&b) end
-    #   end
-    #
-    #   graph = G.new({1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]})
-    #   graph.each_strongly_connected_component {|scc| p scc }
-    #   #=> [4]
-    #   #   [2]
-    #   #   [3]
-    #   #   [1]
-    #
-    #   graph = G.new({1=>[2], 2=>[3, 4], 3=>[2], 4=>[]})
-    #   graph.each_strongly_connected_component {|scc| p scc }
-    #   #=> [4]
-    #   #   [2, 3]
-    #   #   [1]
-    #
-    def each_strongly_connected_component(&block) # :yields: nodes
-      each_node = method(:tsort_each_node)
-      each_child = method(:tsort_each_child)
-      TSort.each_strongly_connected_component(each_node, each_child, &block)
-    end
+  # Returns strongly connected components as an array of arrays of nodes.
+  # The array is sorted from children to parents.
+  # Each elements of the array represents a strongly connected component.
+  #
+  # The graph is represented by _each_node_ and _each_child_.
+  # _each_node_ should have +call+ method which yields for each node in the graph.
+  # _each_child_ should have +call+ method which takes a node argument and yields for each child node.
+  #
+  #   g = {1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]}
+  #   each_node = lambda {|&b| g.each_key(&b) }
+  #   each_child = lambda {|n, &b| g[n].each(&b) }
+  #   p Bundler::TSort.strongly_connected_components(each_node, each_child)
+  #   #=> [[4], [2], [3], [1]]
+  #
+  #   g = {1=>[2], 2=>[3, 4], 3=>[2], 4=>[]}
+  #   each_node = lambda {|&b| g.each_key(&b) }
+  #   each_child = lambda {|n, &b| g[n].each(&b) }
+  #   p Bundler::TSort.strongly_connected_components(each_node, each_child)
+  #   #=> [[4], [2, 3], [1]]
+  #
+  def self.strongly_connected_components(each_node, each_child)
+    each_strongly_connected_component(each_node, each_child).to_a
+  end
 
-    # The iterator version of the TSort.strongly_connected_components method.
-    #
-    # The graph is represented by _each_node_ and _each_child_.
-    # _each_node_ should have +call+ method which yields for each node in the graph.
-    # _each_child_ should have +call+ method which takes a node argument and yields for each child node.
-    #
-    #   g = {1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]}
-    #   each_node = lambda {|&b| g.each_key(&b) }
-    #   each_child = lambda {|n, &b| g[n].each(&b) }
-    #   TSort.each_strongly_connected_component(each_node, each_child) {|scc| p scc }
-    #   #=> [4]
-    #   #   [2]
-    #   #   [3]
-    #   #   [1]
-    #
-    #   g = {1=>[2], 2=>[3, 4], 3=>[2], 4=>[]}
-    #   each_node = lambda {|&b| g.each_key(&b) }
-    #   each_child = lambda {|n, &b| g[n].each(&b) }
-    #   TSort.each_strongly_connected_component(each_node, each_child) {|scc| p scc }
-    #   #=> [4]
-    #   #   [2, 3]
-    #   #   [1]
-    #
-    def TSort.each_strongly_connected_component(each_node, each_child) # :yields: nodes
-      return to_enum(__method__, each_node, each_child) unless block_given?
+  # The iterator version of the #strongly_connected_components method.
+  # <tt><em>obj</em>.each_strongly_connected_component</tt> is similar to
+  # <tt><em>obj</em>.strongly_connected_components.each</tt>, but
+  # modification of _obj_ during the iteration may lead to unexpected results.
+  #
+  # #each_strongly_connected_component returns +nil+.
+  #
+  #   class G
+  #     include Bundler::TSort
+  #     def initialize(g)
+  #       @g = g
+  #     end
+  #     def tsort_each_child(n, &b) @g[n].each(&b) end
+  #     def tsort_each_node(&b) @g.each_key(&b) end
+  #   end
+  #
+  #   graph = G.new({1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]})
+  #   graph.each_strongly_connected_component {|scc| p scc }
+  #   #=> [4]
+  #   #   [2]
+  #   #   [3]
+  #   #   [1]
+  #
+  #   graph = G.new({1=>[2], 2=>[3, 4], 3=>[2], 4=>[]})
+  #   graph.each_strongly_connected_component {|scc| p scc }
+  #   #=> [4]
+  #   #   [2, 3]
+  #   #   [1]
+  #
+  def each_strongly_connected_component(&block) # :yields: nodes
+    each_node = method(:tsort_each_node)
+    each_child = method(:tsort_each_child)
+    Bundler::TSort.each_strongly_connected_component(each_node, each_child, &block)
+  end
 
-      id_map = {}
-      stack = []
-      each_node.call {|node|
-        unless id_map.include? node
-          TSort.each_strongly_connected_component_from(node, each_child, id_map, stack) {|c|
-            yield c
-          }
-        end
-      }
-      nil
-    end
+  # The iterator version of the Bundler::TSort.strongly_connected_components method.
+  #
+  # The graph is represented by _each_node_ and _each_child_.
+  # _each_node_ should have +call+ method which yields for each node in the graph.
+  # _each_child_ should have +call+ method which takes a node argument and yields for each child node.
+  #
+  #   g = {1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]}
+  #   each_node = lambda {|&b| g.each_key(&b) }
+  #   each_child = lambda {|n, &b| g[n].each(&b) }
+  #   Bundler::TSort.each_strongly_connected_component(each_node, each_child) {|scc| p scc }
+  #   #=> [4]
+  #   #   [2]
+  #   #   [3]
+  #   #   [1]
+  #
+  #   g = {1=>[2], 2=>[3, 4], 3=>[2], 4=>[]}
+  #   each_node = lambda {|&b| g.each_key(&b) }
+  #   each_child = lambda {|n, &b| g[n].each(&b) }
+  #   Bundler::TSort.each_strongly_connected_component(each_node, each_child) {|scc| p scc }
+  #   #=> [4]
+  #   #   [2, 3]
+  #   #   [1]
+  #
+  def self.each_strongly_connected_component(each_node, each_child) # :yields: nodes
+    return to_enum(__method__, each_node, each_child) unless block_given?
 
-    # Iterates over strongly connected component in the subgraph reachable from
-    # _node_.
-    #
-    # Return value is unspecified.
-    #
-    # #each_strongly_connected_component_from doesn't call #tsort_each_node.
-    #
-    #   class G
-    #     include TSort
-    #     def initialize(g)
-    #       @g = g
-    #     end
-    #     def tsort_each_child(n, &b) @g[n].each(&b) end
-    #     def tsort_each_node(&b) @g.each_key(&b) end
-    #   end
-    #
-    #   graph = G.new({1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]})
-    #   graph.each_strongly_connected_component_from(2) {|scc| p scc }
-    #   #=> [4]
-    #   #   [2]
-    #
-    #   graph = G.new({1=>[2], 2=>[3, 4], 3=>[2], 4=>[]})
-    #   graph.each_strongly_connected_component_from(2) {|scc| p scc }
-    #   #=> [4]
-    #   #   [2, 3]
-    #
-    def each_strongly_connected_component_from(node, id_map={}, stack=[], &block) # :yields: nodes
-      TSort.each_strongly_connected_component_from(node, method(:tsort_each_child), id_map, stack, &block)
-    end
+    id_map = {}
+    stack = []
+    each_node.call {|node|
+      unless id_map.include? node
+        each_strongly_connected_component_from(node, each_child, id_map, stack) {|c|
+          yield c
+        }
+      end
+    }
+    nil
+  end
 
-    # Iterates over strongly connected components in a graph.
-    # The graph is represented by _node_ and _each_child_.
-    #
-    # _node_ is the first node.
-    # _each_child_ should have +call+ method which takes a node argument
-    # and yields for each child node.
-    #
-    # Return value is unspecified.
-    #
-    # #TSort.each_strongly_connected_component_from is a class method and
-    # it doesn't need a class to represent a graph which includes TSort.
-    #
-    #   graph = {1=>[2], 2=>[3, 4], 3=>[2], 4=>[]}
-    #   each_child = lambda {|n, &b| graph[n].each(&b) }
-    #   TSort.each_strongly_connected_component_from(1, each_child) {|scc|
-    #     p scc
-    #   }
-    #   #=> [4]
-    #   #   [2, 3]
-    #   #   [1]
-    #
-    def TSort.each_strongly_connected_component_from(node, each_child, id_map={}, stack=[]) # :yields: nodes
-      return to_enum(__method__, node, each_child, id_map, stack) unless block_given?
+  # Iterates over strongly connected component in the subgraph reachable from
+  # _node_.
+  #
+  # Return value is unspecified.
+  #
+  # #each_strongly_connected_component_from doesn't call #tsort_each_node.
+  #
+  #   class G
+  #     include Bundler::TSort
+  #     def initialize(g)
+  #       @g = g
+  #     end
+  #     def tsort_each_child(n, &b) @g[n].each(&b) end
+  #     def tsort_each_node(&b) @g.each_key(&b) end
+  #   end
+  #
+  #   graph = G.new({1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]})
+  #   graph.each_strongly_connected_component_from(2) {|scc| p scc }
+  #   #=> [4]
+  #   #   [2]
+  #
+  #   graph = G.new({1=>[2], 2=>[3, 4], 3=>[2], 4=>[]})
+  #   graph.each_strongly_connected_component_from(2) {|scc| p scc }
+  #   #=> [4]
+  #   #   [2, 3]
+  #
+  def each_strongly_connected_component_from(node, id_map={}, stack=[], &block) # :yields: nodes
+    Bundler::TSort.each_strongly_connected_component_from(node, method(:tsort_each_child), id_map, stack, &block)
+  end
 
-      minimum_id = node_id = id_map[node] = id_map.size
-      stack_length = stack.length
-      stack << node
+  # Iterates over strongly connected components in a graph.
+  # The graph is represented by _node_ and _each_child_.
+  #
+  # _node_ is the first node.
+  # _each_child_ should have +call+ method which takes a node argument
+  # and yields for each child node.
+  #
+  # Return value is unspecified.
+  #
+  # #Bundler::TSort.each_strongly_connected_component_from is a class method and
+  # it doesn't need a class to represent a graph which includes Bundler::TSort.
+  #
+  #   graph = {1=>[2], 2=>[3, 4], 3=>[2], 4=>[]}
+  #   each_child = lambda {|n, &b| graph[n].each(&b) }
+  #   Bundler::TSort.each_strongly_connected_component_from(1, each_child) {|scc|
+  #     p scc
+  #   }
+  #   #=> [4]
+  #   #   [2, 3]
+  #   #   [1]
+  #
+  def self.each_strongly_connected_component_from(node, each_child, id_map={}, stack=[]) # :yields: nodes
+    return to_enum(__method__, node, each_child, id_map, stack) unless block_given?
 
-      each_child.call(node) {|child|
-        if id_map.include? child
-          child_id = id_map[child]
-          minimum_id = child_id if child_id && child_id < minimum_id
-        else
-          sub_minimum_id =
-            TSort.each_strongly_connected_component_from(child, each_child, id_map, stack) {|c|
-              yield c
-            }
-          minimum_id = sub_minimum_id if sub_minimum_id < minimum_id
-        end
-      }
+    minimum_id = node_id = id_map[node] = id_map.size
+    stack_length = stack.length
+    stack << node
 
-      if node_id == minimum_id
-        component = stack.slice!(stack_length .. -1)
-        component.each {|n| id_map[n] = nil}
-        yield component
+    each_child.call(node) {|child|
+      if id_map.include? child
+        child_id = id_map[child]
+        minimum_id = child_id if child_id && child_id < minimum_id
+      else
+        sub_minimum_id =
+          each_strongly_connected_component_from(child, each_child, id_map, stack) {|c|
+            yield c
+          }
+        minimum_id = sub_minimum_id if sub_minimum_id < minimum_id
       end
+    }
 
-      minimum_id
+    if node_id == minimum_id
+      component = stack.slice!(stack_length .. -1)
+      component.each {|n| id_map[n] = nil}
+      yield component
     end
 
-    # Should be implemented by a extended class.
-    #
-    # #tsort_each_node is used to iterate for all nodes over a graph.
-    #
-    def tsort_each_node # :yields: node
-      raise NotImplementedError.new
-    end
+    minimum_id
+  end
 
-    # Should be implemented by a extended class.
-    #
-    # #tsort_each_child is used to iterate for child nodes of _node_.
-    #
-    def tsort_each_child(node) # :yields: child
-      raise NotImplementedError.new
-    end
+  # Should be implemented by a extended class.
+  #
+  # #tsort_each_node is used to iterate for all nodes over a graph.
+  #
+  def tsort_each_node # :yields: node
+    raise NotImplementedError.new
+  end
+
+  # Should be implemented by a extended class.
+  #
+  # #tsort_each_child is used to iterate for child nodes of _node_.
+  #
+  def tsort_each_child(node) # :yields: child
+    raise NotImplementedError.new
   end
 end
diff --git a/lib/bundler/vendor/uri/lib/uri.rb b/lib/bundler/vendor/uri/lib/uri.rb
index 0e574dd2b1..976320f6bd 100644
--- a/lib/bundler/vendor/uri/lib/uri.rb
+++ b/lib/bundler/vendor/uri/lib/uri.rb
@@ -30,7 +30,7 @@
 #     class RSYNC < Generic
 #       DEFAULT_PORT = 873
 #     end
-#     @@schemes['RSYNC'] = RSYNC
+#     register_scheme 'RSYNC', RSYNC
 #   end
 #   #=> Bundler::URI::RSYNC
 #
@@ -70,7 +70,6 @@
 # - Bundler::URI::REGEXP - (in uri/common.rb)
 #   - Bundler::URI::REGEXP::PATTERN - (in uri/common.rb)
 # - Bundler::URI::Util - (in uri/common.rb)
-# - Bundler::URI::Escape - (in uri/common.rb)
 # - Bundler::URI::Error - (in uri/common.rb)
 #   - Bundler::URI::InvalidURIError - (in uri/common.rb)
 #   - Bundler::URI::InvalidComponentError - (in uri/common.rb)
@@ -101,3 +100,5 @@ require_relative 'uri/https'
 require_relative 'uri/ldap'
 require_relative 'uri/ldaps'
 require_relative 'uri/mailto'
+require_relative 'uri/ws'
+require_relative 'uri/wss'
diff --git a/lib/bundler/vendor/uri/lib/uri/common.rb b/lib/bundler/vendor/uri/lib/uri/common.rb
index 6539e1810f..914a4c7581 100644
--- a/lib/bundler/vendor/uri/lib/uri/common.rb
+++ b/lib/bundler/vendor/uri/lib/uri/common.rb
@@ -13,9 +13,12 @@ require_relative "rfc2396_parser"
 require_relative "rfc3986_parser"
 
 module Bundler::URI
+  include RFC2396_REGEXP
+
   REGEXP = RFC2396_REGEXP
   Parser = RFC2396_Parser
   RFC3986_PARSER = RFC3986_Parser.new
+  Ractor.make_shareable(RFC3986_PARSER) if defined?(Ractor)
 
   # Bundler::URI::Parser.new
   DEFAULT_PARSER = Parser.new
@@ -27,6 +30,7 @@ module Bundler::URI
   DEFAULT_PARSER.regexp.each_pair do |sym, str|
     const_set(sym, str)
   end
+  Ractor.make_shareable(DEFAULT_PARSER) if defined?(Ractor)
 
   module Util # :nodoc:
     def make_components_hash(klass, array_hash)
@@ -60,24 +64,42 @@ module Bundler::URI
     module_function :make_components_hash
   end
 
-  include REGEXP
+  module Schemes
+  end
+  private_constant :Schemes
+
+  #
+  # Register the given +klass+ to be instantiated when parsing URLs with the given +scheme+.
+  # Note that currently only schemes which after .upcase are valid constant names
+  # can be registered (no -/+/. allowed).
+  #
+  def self.register_scheme(scheme, klass)
+    Schemes.const_set(scheme.to_s.upcase, klass)
+  end
 
-  @@schemes = {}
   # Returns a Hash of the defined schemes.
   def self.scheme_list
-    @@schemes
+    Schemes.constants.map { |name|
+      [name.to_s.upcase, Schemes.const_get(name)]
+    }.to_h
   end
 
+  INITIAL_SCHEMES = scheme_list
+  private_constant :INITIAL_SCHEMES
+  Ractor.make_shareable(INITIAL_SCHEMES) if defined?(Ractor)
+
   #
   # Construct a Bundler::URI instance, using the scheme to detect the appropriate class
   # from +Bundler::URI.scheme_list+.
   #
   def self.for(scheme, *arguments, default: Generic)
-    if scheme
-      uri_class = @@schemes[scheme.upcase] || default
-    else
-      uri_class = default
+    const_name = scheme.to_s.upcase
+
+    uri_class = INITIAL_SCHEMES[const_name]
+    uri_class ||= if /\A[A-Z]\w*\z/.match?(const_name) && Schemes.const_defined?(const_name, false)
+      Schemes.const_get(const_name, false)
     end
+    uri_class ||= default
 
     return uri_class.new(scheme, *arguments)
   end
@@ -278,6 +300,7 @@ module Bundler::URI
   256.times do |i|
     TBLENCWWWCOMP_[-i.chr] = -('%%%02X' % i)
   end
+  TBLENCURICOMP_ = TBLENCWWWCOMP_.dup.freeze
   TBLENCWWWCOMP_[' '] = '+'
   TBLENCWWWCOMP_.freeze
   TBLDECWWWCOMP_ = {} # :nodoc:
@@ -303,6 +326,33 @@ module Bundler::URI
   #
   # See Bundler::URI.decode_www_form_component, Bundler::URI.encode_www_form.
   def self.encode_www_form_component(str, enc=nil)
+    _encode_uri_component(/[^*\-.0-9A-Z_a-z]/, TBLENCWWWCOMP_, str, enc)
+  end
+
+  # Decodes given +str+ of URL-encoded form data.
+  #
+  # This decodes + to SP.
+  #
+  # See Bundler::URI.encode_www_form_component, Bundler::URI.decode_www_form.
+  def self.decode_www_form_component(str, enc=Encoding::UTF_8)
+    _decode_uri_component(/\+|%\h\h/, str, enc)
+  end
+
+  # Encodes +str+ using URL encoding
+  #
+  # This encodes SP to %20 instead of +.
+  def self.encode_uri_component(str, enc=nil)
+    _encode_uri_component(/[^*\-.0-9A-Z_a-z]/, TBLENCURICOMP_, str, enc)
+  end
+
+  # Decodes given +str+ of URL-encoded data.
+  #
+  # This does not decode + to SP.
+  def self.decode_uri_component(str, enc=Encoding::UTF_8)
+    _decode_uri_component(/%\h\h/, str, enc)
+  end
+
+  def self._encode_uri_component(regexp, table, str, enc)
     str = str.to_s.dup
     if str.encoding != Encoding::ASCII_8BIT
       if enc && enc != Encoding::ASCII_8BIT
@@ -311,19 +361,16 @@ module Bundler::URI
       end
       str.force_encoding(Encoding::ASCII_8BIT)
     end
-    str.gsub!(/[^*\-.0-9A-Z_a-z]/, TBLENCWWWCOMP_)
+    str.gsub!(regexp, table)
     str.force_encoding(Encoding::US_ASCII)
   end
+  private_class_method :_encode_uri_component
 
-  # Decodes given +str+ of URL-encoded form data.
-  #
-  # This decodes + to SP.
-  #
-  # See Bundler::URI.encode_www_form_component, Bundler::URI.decode_www_form.
-  def self.decode_www_form_component(str, enc=Encoding::UTF_8)
-    raise ArgumentError, "invalid %-encoding (#{str})" if /%(?!\h\h)/ =~ str
-    str.b.gsub(/\+|%\h\h/, TBLDECWWWCOMP_).force_encoding(enc)
+  def self._decode_uri_component(regexp, str, enc)
+    raise ArgumentError, "invalid %-encoding (#{str})" if /%(?!\h\h)/.match?(str)
+    str.b.gsub(regexp, TBLDECWWWCOMP_).force_encoding(enc)
   end
+  private_class_method :_decode_uri_component
 
   # Generates URL-encoded form data from given +enum+.
   #
@@ -653,6 +700,7 @@ module Bundler::URI
     "utf-16"=>"utf-16le",
     "utf-16le"=>"utf-16le",
   } # :nodoc:
+  Ractor.make_shareable(WEB_ENCODINGS_) if defined?(Ractor)
 
   # :nodoc:
   # return encoding or nil
diff --git a/lib/bundler/vendor/uri/lib/uri/file.rb b/lib/bundler/vendor/uri/lib/uri/file.rb
index df42f8bcdd..8d75a9de7a 100644
--- a/lib/bundler/vendor/uri/lib/uri/file.rb
+++ b/lib/bundler/vendor/uri/lib/uri/file.rb
@@ -33,6 +33,9 @@ module Bundler::URI
     # If an Array is used, the components must be passed in the
     # order <code>[host, path]</code>.
     #
+    # A path from e.g. the File class should be escaped before
+    # being passed.
+    #
     # Examples:
     #
     #     require 'bundler/vendor/uri/lib/uri'
@@ -44,6 +47,9 @@ module Bundler::URI
     #       :path => '/ruby/src'})
     #     uri2.to_s  # => "file://host.example.com/ruby/src"
     #
+    #     uri3 = Bundler::URI::File.build({:path => Bundler::URI::escape('/path/my file.txt')})
+    #     uri3.to_s  # => "file:///path/my%20file.txt"
+    #
     def self.build(args)
       tmp = Util::make_components_hash(self, args)
       super(tmp)
@@ -90,5 +96,5 @@ module Bundler::URI
     end
   end
 
-  @@schemes['FILE'] = File
+  register_scheme 'FILE', File
 end
diff --git a/lib/bundler/vendor/uri/lib/uri/ftp.rb b/lib/bundler/vendor/uri/lib/uri/ftp.rb
index 2252e405d5..48b4c6718d 100644
--- a/lib/bundler/vendor/uri/lib/uri/ftp.rb
+++ b/lib/bundler/vendor/uri/lib/uri/ftp.rb
@@ -262,5 +262,6 @@ module Bundler::URI
       return str
     end
   end
-  @@schemes['FTP'] = FTP
+
+  register_scheme 'FTP', FTP
 end
diff --git a/lib/bundler/vendor/uri/lib/uri/generic.rb b/lib/bundler/vendor/uri/lib/uri/generic.rb
index f29ba6cf18..9ae6915826 100644
--- a/lib/bundler/vendor/uri/lib/uri/generic.rb
+++ b/lib/bundler/vendor/uri/lib/uri/generic.rb
@@ -564,16 +564,26 @@ module Bundler::URI
       end
     end
 
-    # Returns the user component.
+    # Returns the user component (without Bundler::URI decoding).
     def user
       @user
     end
 
-    # Returns the password component.
+    # Returns the password component (without Bundler::URI decoding).
     def password
       @password
     end
 
+    # Returns the user component after Bundler::URI decoding.
+    def decoded_user
+      Bundler::URI.decode_uri_component(@user) if @user
+    end
+
+    # Returns the password component after Bundler::URI decoding.
+    def decoded_password
+      Bundler::URI.decode_uri_component(@password) if @password
+    end
+
     #
     # Checks the host +v+ component for RFC2396 compliance
     # and against the Bundler::URI::Parser Regexp for :HOST.
@@ -643,7 +653,7 @@ module Bundler::URI
     #
     def hostname
       v = self.host
-      /\A\[(.*)\]\z/ =~ v ? $1 : v
+      v&.start_with?('[') && v.end_with?(']') ? v[1..-2] : v
     end
 
     # Sets the host part of the Bundler::URI as the argument with brackets for IPv6 addresses.
@@ -659,7 +669,7 @@ module Bundler::URI
     # it is wrapped with brackets.
     #
     def hostname=(v)
-      v = "[#{v}]" if /\A\[.*\]\z/ !~ v && /:/ =~ v
+      v = "[#{v}]" if !(v&.start_with?('[') && v&.end_with?(']')) && v&.index(':')
       self.host = v
     end
 
@@ -1514,9 +1524,19 @@ module Bundler::URI
           proxy_uri = env["CGI_#{name.upcase}"]
         end
       elsif name == 'http_proxy'
-        unless proxy_uri = env[name]
-          if proxy_uri = env[name.upcase]
-            warn 'The environment variable HTTP_PROXY is discouraged.  Use http_proxy.', uplevel: 1
+        if RUBY_ENGINE == 'jruby' && p_addr = ENV_JAVA['http.proxyHost']
+          p_port = ENV_JAVA['http.proxyPort']
+          if p_user = ENV_JAVA['http.proxyUser']
+            p_pass = ENV_JAVA['http.proxyPass']
+            proxy_uri = "http://#{p_user}:#{p_pass}@#{p_addr}:#{p_port}"
+          else
+            proxy_uri = "http://#{p_addr}:#{p_port}"
+          end
+        else
+          unless proxy_uri = env[name]
+            if proxy_uri = env[name.upcase]
+              warn 'The environment variable HTTP_PROXY is discouraged.  Use http_proxy.', uplevel: 1
+            end
           end
         end
       else
diff --git a/lib/bundler/vendor/uri/lib/uri/http.rb b/lib/bundler/vendor/uri/lib/uri/http.rb
index 50d7e427a5..2c44810644 100644
--- a/lib/bundler/vendor/uri/lib/uri/http.rb
+++ b/lib/bundler/vendor/uri/lib/uri/http.rb
@@ -80,8 +80,46 @@ module Bundler::URI
       url = @query ? "#@path?#@query" : @path.dup
       url.start_with?(?/.freeze) ? url : ?/ + url
     end
-  end
 
-  @@schemes['HTTP'] = HTTP
+    #
+    # == Description
+    #
+    # Returns the authority for an HTTP uri, as defined in
+    # https://datatracker.ietf.org/doc/html/rfc3986/#section-3.2.
+    #
+    #
+    # Example:
+    #
+    #     Bundler::URI::HTTP.build(host: 'www.example.com', path: '/foo/bar').authority #=> "www.example.com"
+    #     Bundler::URI::HTTP.build(host: 'www.example.com', port: 8000, path: '/foo/bar').authority #=> "www.example.com:8000"
+    #     Bundler::URI::HTTP.build(host: 'www.example.com', port: 80, path: '/foo/bar').authority #=> "www.example.com"
+    #
+    def authority
+      if port == default_port
+        host
+      else
+        "#{host}:#{port}"
+      end
+    end
+
+    #
+    # == Description
+    #
+    # Returns the origin for an HTTP uri, as defined in
+    # https://datatracker.ietf.org/doc/html/rfc6454.
+    #
+    #
+    # Example:
+    #
+    #     Bundler::URI::HTTP.build(host: 'www.example.com', path: '/foo/bar').origin #=> "http://www.example.com"
+    #     Bundler::URI::HTTP.build(host: 'www.example.com', port: 8000, path: '/foo/bar').origin #=> "http://www.example.com:8000"
+    #     Bundler::URI::HTTP.build(host: 'www.example.com', port: 80, path: '/foo/bar').origin #=> "http://www.example.com"
+    #     Bundler::URI::HTTPS.build(host: 'www.example.com', path: '/foo/bar').origin #=> "https://www.example.com"
+    #
+    def origin
+      "#{scheme}://#{authority}"
+    end
+  end
 
+  register_scheme 'HTTP', HTTP
 end
diff --git a/lib/bundler/vendor/uri/lib/uri/https.rb b/lib/bundler/vendor/uri/lib/uri/https.rb
index 4fd4e9af7b..e4556e3ecb 100644
--- a/lib/bundler/vendor/uri/lib/uri/https.rb
+++ b/lib/bundler/vendor/uri/lib/uri/https.rb
@@ -18,5 +18,6 @@ module Bundler::URI
     # A Default port of 443 for Bundler::URI::HTTPS
     DEFAULT_PORT = 443
   end
-  @@schemes['HTTPS'] = HTTPS
+
+  register_scheme 'HTTPS', HTTPS
 end
diff --git a/lib/bundler/vendor/uri/lib/uri/ldap.rb b/lib/bundler/vendor/uri/lib/uri/ldap.rb
index 6e9e1918f6..9811b6e2f5 100644
--- a/lib/bundler/vendor/uri/lib/uri/ldap.rb
+++ b/lib/bundler/vendor/uri/lib/uri/ldap.rb
@@ -257,5 +257,5 @@ module Bundler::URI
     end
   end
 
-  @@schemes['LDAP'] = LDAP
+  register_scheme 'LDAP', LDAP
 end
diff --git a/lib/bundler/vendor/uri/lib/uri/ldaps.rb b/lib/bundler/vendor/uri/lib/uri/ldaps.rb
index 0af35bb16b..c786168450 100644
--- a/lib/bundler/vendor/uri/lib/uri/ldaps.rb
+++ b/lib/bundler/vendor/uri/lib/uri/ldaps.rb
@@ -17,5 +17,6 @@ module Bundler::URI
     # A Default port of 636 for Bundler::URI::LDAPS
     DEFAULT_PORT = 636
   end
-  @@schemes['LDAPS'] = LDAPS
+
+  register_scheme 'LDAPS', LDAPS
 end
diff --git a/lib/bundler/vendor/uri/lib/uri/mailto.rb b/lib/bundler/vendor/uri/lib/uri/mailto.rb
index ff7ab7e114..ff2e30be86 100644
--- a/lib/bundler/vendor/uri/lib/uri/mailto.rb
+++ b/lib/bundler/vendor/uri/lib/uri/mailto.rb
@@ -15,7 +15,7 @@ module Bundler::URI
   # RFC6068, the mailto URL scheme.
   #
   class MailTo < Generic
-    include REGEXP
+    include RFC2396_REGEXP
 
     # A Default port of nil for Bundler::URI::MailTo.
     DEFAULT_PORT = nil
@@ -289,5 +289,5 @@ module Bundler::URI
     alias to_rfc822text to_mailtext
   end
 
-  @@schemes['MAILTO'] = MailTo
+  register_scheme 'MAILTO', MailTo
 end
diff --git a/lib/bundler/vendor/uri/lib/uri/rfc2396_parser.rb b/lib/bundler/vendor/uri/lib/uri/rfc2396_parser.rb
index e48e164f4c..09c22c9906 100644
--- a/lib/bundler/vendor/uri/lib/uri/rfc2396_parser.rb
+++ b/lib/bundler/vendor/uri/lib/uri/rfc2396_parser.rb
@@ -116,7 +116,7 @@ module Bundler::URI
     # See also Bundler::URI::Parser.initialize_regexp.
     attr_reader :regexp
 
-    # Returns a split Bundler::URI against regexp[:ABS_URI].
+    # Returns a split Bundler::URI against +regexp[:ABS_URI]+.
     def split(uri)
       case uri
       when ''
@@ -257,8 +257,8 @@ module Bundler::URI
       end
     end
 
-    # Returns Regexp that is default self.regexp[:ABS_URI_REF],
-    # unless +schemes+ is provided. Then it is a Regexp.union with self.pattern[:X_ABS_URI].
+    # Returns Regexp that is default +self.regexp[:ABS_URI_REF]+,
+    # unless +schemes+ is provided. Then it is a Regexp.union with +self.pattern[:X_ABS_URI]+.
     def make_regexp(schemes = nil)
       unless schemes
         @regexp[:ABS_URI_REF]
@@ -277,7 +277,7 @@ module Bundler::URI
     # +str+::
     #    String to make safe
     # +unsafe+::
-    #    Regexp to apply. Defaults to self.regexp[:UNSAFE]
+    #    Regexp to apply. Defaults to +self.regexp[:UNSAFE]+
     #
     # == Description
     #
@@ -309,7 +309,7 @@ module Bundler::URI
     # +str+::
     #    String to remove escapes from
     # +escaped+::
-    #    Regexp to apply. Defaults to self.regexp[:ESCAPED]
+    #    Regexp to apply. Defaults to +self.regexp[:ESCAPED]+
     #
     # == Description
     #
@@ -322,8 +322,14 @@ module Bundler::URI
     end
 
     @@to_s = Kernel.instance_method(:to_s)
-    def inspect
-      @@to_s.bind_call(self)
+    if @@to_s.respond_to?(:bind_call)
+      def inspect
+        @@to_s.bind_call(self)
+      end
+    else
+      def inspect
+        @@to_s.bind(self).call
+      end
     end
 
     private
@@ -491,8 +497,8 @@ module Bundler::URI
       ret = {}
 
       # for Bundler::URI::split
-      ret[:ABS_URI] = Regexp.new('\A\s*' + pattern[:X_ABS_URI] + '\s*\z', Regexp::EXTENDED)
-      ret[:REL_URI] = Regexp.new('\A\s*' + pattern[:X_REL_URI] + '\s*\z', Regexp::EXTENDED)
+      ret[:ABS_URI] = Regexp.new('\A\s*+' + pattern[:X_ABS_URI] + '\s*\z', Regexp::EXTENDED)
+      ret[:REL_URI] = Regexp.new('\A\s*+' + pattern[:X_REL_URI] + '\s*\z', Regexp::EXTENDED)
 
       # for Bundler::URI::extract
       ret[:URI_REF]     = Regexp.new(pattern[:URI_REF])
diff --git a/lib/bundler/vendor/uri/lib/uri/rfc3986_parser.rb b/lib/bundler/vendor/uri/lib/uri/rfc3986_parser.rb
index 2029cfd056..a85511c146 100644
--- a/lib/bundler/vendor/uri/lib/uri/rfc3986_parser.rb
+++ b/lib/bundler/vendor/uri/lib/uri/rfc3986_parser.rb
@@ -2,9 +2,8 @@
 module Bundler::URI
   class RFC3986_Parser # :nodoc:
     # Bundler::URI defined in RFC3986
-    # this regexp is modified not to host is not empty string
-    RFC3986_URI = /\A(?<Bundler::URI>(?<scheme>[A-Za-z][+\-.0-9A-Za-z]*):(?<hier-part>\/\/(?<authority>(?:(?<userinfo>(?:%\h\h|[!$&-.0-;=A-Z_a-z~])*)@)?(?<host>(?<IP-literal>\[(?:(?<IPv6address>(?:\h{1,4}:){6}(?<ls32>\h{1,4}:\h{1,4}|(?<IPv4address>(?<dec-octet>[1-9]\d|1\d{2}|2[0-4]\d|25[0-5]|\d)\.\g<dec-octet>\.\g<dec-octet>\.\g<dec-octet>))|::(?:\h{1,4}:){5}\g<ls32>|\h{1,4}?::(?:\h{1,4}:){4}\g<ls32>|(?:(?:\h{1,4}:)?\h{1,4})?::(?:\h{1,4}:){3}\g<ls32>|(?:(?:\h{1,4}:){,2}\h{1,4})?::(?:\h{1,4}:){2}\g<ls32>|(?:(?:\h{1,4}:){,3}\h{1,4})?::\h{1,4}:\g<ls32>|(?:(?:\h{1,4}:){,4}\h{1,4})?::\g<ls32>|(?:(?:\h{1,4}:){,5}\h{1,4})?::\h{1,4}|(?:(?:\h{1,4}:){,6}\h{1,4})?::)|(?<IPvFuture>v\h+\.[!$&-.0-;=A-Z_a-z~]+))\])|\g<IPv4address>|(?<reg-name>(?:%\h\h|[!$&-.0-9;=A-Z_a-z~])+))?(?::(?<port>\d*))?)(?<path-abempty>(?:\/(?<segment>(?:%\h\h|[!$&-.0-;=@-Z_a-z~])*))*)|(?<path-absolute>\/(?:(?<segment-nz>(?:%\h\h|[!$&-.0-;=@-Z_a-z~])+)(?:\/\g<segment>)*)?)|(?<path-rootless>\g<segment-nz>(?:\/\g<segment>)*)|(?<path-empty>))(?:\?(?<query>[^#]*))?(?:\#(?<fragment>(?:%\h\h|[!$&-.0-;=@-Z_a-z~\/?])*))?)\z/
-    RFC3986_relative_ref = /\A(?<relative-ref>(?<relative-part>\/\/(?<authority>(?:(?<userinfo>(?:%\h\h|[!$&-.0-;=A-Z_a-z~])*)@)?(?<host>(?<IP-literal>\[(?<IPv6address>(?:\h{1,4}:){6}(?<ls32>\h{1,4}:\h{1,4}|(?<IPv4address>(?<dec-octet>[1-9]\d|1\d{2}|2[0-4]\d|25[0-5]|\d)\.\g<dec-octet>\.\g<dec-octet>\.\g<dec-octet>))|::(?:\h{1,4}:){5}\g<ls32>|\h{1,4}?::(?:\h{1,4}:){4}\g<ls32>|(?:(?:\h{1,4}:){,1}\h{1,4})?::(?:\h{1,4}:){3}\g<ls32>|(?:(?:\h{1,4}:){,2}\h{1,4})?::(?:\h{1,4}:){2}\g<ls32>|(?:(?:\h{1,4}:){,3}\h{1,4})?::\h{1,4}:\g<ls32>|(?:(?:\h{1,4}:){,4}\h{1,4})?::\g<ls32>|(?:(?:\h{1,4}:){,5}\h{1,4})?::\h{1,4}|(?:(?:\h{1,4}:){,6}\h{1,4})?::)|(?<IPvFuture>v\h+\.[!$&-.0-;=A-Z_a-z~]+)\])|\g<IPv4address>|(?<reg-name>(?:%\h\h|[!$&-.0-9;=A-Z_a-z~])+))?(?::(?<port>\d*))?)(?<path-abempty>(?:\/(?<segment>(?:%\h\h|[!$&-.0-;=@-Z_a-z~])*))*)|(?<path-absolute>\/(?:(?<segment-nz>(?:%\h\h|[!$&-.0-;=@-Z_a-z~])+)(?:\/\g<segment>)*)?)|(?<path-noscheme>(?<segment-nz-nc>(?:%\h\h|[!$&-.0-9;=@-Z_a-z~])+)(?:\/\g<segment>)*)|(?<path-empty>))(?:\?(?<query>[^#]*))?(?:\#(?<fragment>(?:%\h\h|[!$&-.0-;=@-Z_a-z~\/?])*))?)\z/
+    RFC3986_URI = /\A(?<Bundler::URI>(?<scheme>[A-Za-z][+\-.0-9A-Za-z]*+):(?<hier-part>\/\/(?<authority>(?:(?<userinfo>(?:%\h\h|[!$&-.0-;=A-Z_a-z~])*+)@)?(?<host>(?<IP-literal>\[(?:(?<IPv6address>(?:\h{1,4}:){6}(?<ls32>\h{1,4}:\h{1,4}|(?<IPv4address>(?<dec-octet>[1-9]\d|1\d{2}|2[0-4]\d|25[0-5]|\d)\.\g<dec-octet>\.\g<dec-octet>\.\g<dec-octet>))|::(?:\h{1,4}:){5}\g<ls32>|\h{1,4}?::(?:\h{1,4}:){4}\g<ls32>|(?:(?:\h{1,4}:)?\h{1,4})?::(?:\h{1,4}:){3}\g<ls32>|(?:(?:\h{1,4}:){,2}\h{1,4})?::(?:\h{1,4}:){2}\g<ls32>|(?:(?:\h{1,4}:){,3}\h{1,4})?::\h{1,4}:\g<ls32>|(?:(?:\h{1,4}:){,4}\h{1,4})?::\g<ls32>|(?:(?:\h{1,4}:){,5}\h{1,4})?::\h{1,4}|(?:(?:\h{1,4}:){,6}\h{1,4})?::)|(?<IPvFuture>v\h++\.[!$&-.0-;=A-Z_a-z~]++))\])|\g<IPv4address>|(?<reg-name>(?:%\h\h|[!$&-.0-9;=A-Z_a-z~])*+))(?::(?<port>\d*+))?)(?<path-abempty>(?:\/(?<segment>(?:%\h\h|[!$&-.0-;=@-Z_a-z~])*+))*+)|(?<path-absolute>\/(?:(?<segment-nz>(?:%\h\h|[!$&-.0-;=@-Z_a-z~])++)(?:\/\g<segment>)*+)?)|(?<path-rootless>\g<segment-nz>(?:\/\g<segment>)*+)|(?<path-empty>))(?:\?(?<query>[^#]*+))?(?:\#(?<fragment>(?:%\h\h|[!$&-.0-;=@-Z_a-z~\/?])*+))?)\z/
+    RFC3986_relative_ref = /\A(?<relative-ref>(?<relative-part>\/\/(?<authority>(?:(?<userinfo>(?:%\h\h|[!$&-.0-;=A-Z_a-z~])*+)@)?(?<host>(?<IP-literal>\[(?:(?<IPv6address>(?:\h{1,4}:){6}(?<ls32>\h{1,4}:\h{1,4}|(?<IPv4address>(?<dec-octet>[1-9]\d|1\d{2}|2[0-4]\d|25[0-5]|\d)\.\g<dec-octet>\.\g<dec-octet>\.\g<dec-octet>))|::(?:\h{1,4}:){5}\g<ls32>|\h{1,4}?::(?:\h{1,4}:){4}\g<ls32>|(?:(?:\h{1,4}:){,1}\h{1,4})?::(?:\h{1,4}:){3}\g<ls32>|(?:(?:\h{1,4}:){,2}\h{1,4})?::(?:\h{1,4}:){2}\g<ls32>|(?:(?:\h{1,4}:){,3}\h{1,4})?::\h{1,4}:\g<ls32>|(?:(?:\h{1,4}:){,4}\h{1,4})?::\g<ls32>|(?:(?:\h{1,4}:){,5}\h{1,4})?::\h{1,4}|(?:(?:\h{1,4}:){,6}\h{1,4})?::)|(?<IPvFuture>v\h++\.[!$&-.0-;=A-Z_a-z~]++))\])|\g<IPv4address>|(?<reg-name>(?:%\h\h|[!$&-.0-9;=A-Z_a-z~])++))?(?::(?<port>\d*+))?)(?<path-abempty>(?:\/(?<segment>(?:%\h\h|[!$&-.0-;=@-Z_a-z~])*+))*+)|(?<path-absolute>\/(?:(?<segment-nz>(?:%\h\h|[!$&-.0-;=@-Z_a-z~])++)(?:\/\g<segment>)*+)?)|(?<path-noscheme>(?<segment-nz-nc>(?:%\h\h|[!$&-.0-9;=@-Z_a-z~])++)(?:\/\g<segment>)*+)|(?<path-empty>))(?:\?(?<query>[^#]*+))?(?:\#(?<fragment>(?:%\h\h|[!$&-.0-;=@-Z_a-z~\/?])*+))?)\z/
     attr_reader :regexp
 
     def initialize
@@ -79,8 +78,14 @@ module Bundler::URI
     end
 
     @@to_s = Kernel.instance_method(:to_s)
-    def inspect
-      @@to_s.bind_call(self)
+    if @@to_s.respond_to?(:bind_call)
+      def inspect
+        @@to_s.bind_call(self)
+      end
+    else
+      def inspect
+        @@to_s.bind(self).call
+      end
     end
 
     private
@@ -95,7 +100,7 @@ module Bundler::URI
         QUERY: /\A(?:%\h\h|[!$&-.0-;=@-Z_a-z~\/?])*\z/,
         FRAGMENT: /\A(?:%\h\h|[!$&-.0-;=@-Z_a-z~\/?])*\z/,
         OPAQUE: /\A(?:[^\/].*)?\z/,
-        PORT: /\A[\x09\x0a\x0c\x0d ]*\d*[\x09\x0a\x0c\x0d ]*\z/,
+        PORT: /\A[\x09\x0a\x0c\x0d ]*+\d*[\x09\x0a\x0c\x0d ]*\z/,
       }
     end
 
diff --git a/lib/bundler/vendor/uri/lib/uri/version.rb b/lib/bundler/vendor/uri/lib/uri/version.rb
index f2bb0ebad2..84b08eee30 100644
--- a/lib/bundler/vendor/uri/lib/uri/version.rb
+++ b/lib/bundler/vendor/uri/lib/uri/version.rb
@@ -1,6 +1,6 @@
 module Bundler::URI
   # :stopdoc:
-  VERSION_CODE = '001001'.freeze
+  VERSION_CODE = '001202'.freeze
   VERSION = VERSION_CODE.scan(/../).collect{|n| n.to_i}.join('.').freeze
   # :startdoc:
 end
diff --git a/lib/bundler/vendor/uri/lib/uri/ws.rb b/lib/bundler/vendor/uri/lib/uri/ws.rb
index 58e08bf98e..10ae6f5834 100644
--- a/lib/bundler/vendor/uri/lib/uri/ws.rb
+++ b/lib/bundler/vendor/uri/lib/uri/ws.rb
@@ -79,6 +79,5 @@ module Bundler::URI
     end
   end
 
-  @@schemes['WS'] = WS
-
+  register_scheme 'WS', WS
 end
diff --git a/lib/bundler/vendor/uri/lib/uri/wss.rb b/lib/bundler/vendor/uri/lib/uri/wss.rb
index 3827053c7b..e8db1ceabf 100644
--- a/lib/bundler/vendor/uri/lib/uri/wss.rb
+++ b/lib/bundler/vendor/uri/lib/uri/wss.rb
@@ -18,5 +18,6 @@ module Bundler::URI
     # A Default port of 443 for Bundler::URI::WSS
     DEFAULT_PORT = 443
   end
-  @@schemes['WSS'] = WSS
+
+  register_scheme 'WSS', WSS
 end
diff --git a/lib/bundler/vendored_molinillo.rb b/lib/bundler/vendored_molinillo.rb
deleted file mode 100644
index d1976f5cb4..0000000000
--- a/lib/bundler/vendored_molinillo.rb
+++ /dev/null
@@ -1,4 +0,0 @@
-# frozen_string_literal: true
-
-module Bundler; end
-require_relative "vendor/molinillo/lib/molinillo"
diff --git a/lib/bundler/vendored_persistent.rb b/lib/bundler/vendored_persistent.rb
index dc9573e025..e29f27cdfd 100644
--- a/lib/bundler/vendored_persistent.rb
+++ b/lib/bundler/vendored_persistent.rb
@@ -11,37 +11,5 @@ end
 require_relative "vendor/net-http-persistent/lib/net/http/persistent"
 
 module Bundler
-  class PersistentHTTP < Persistent::Net::HTTP::Persistent
-    def connection_for(uri)
-      super(uri) do |connection|
-        result = yield connection
-        warn_old_tls_version_rubygems_connection(uri, connection)
-        result
-      end
-    end
-
-    def warn_old_tls_version_rubygems_connection(uri, connection)
-      return unless connection.http.use_ssl?
-      return unless (uri.host || "").end_with?("rubygems.org")
-
-      socket = connection.instance_variable_get(:@socket)
-      return unless socket
-      socket_io = socket.io
-      return unless socket_io.respond_to?(:ssl_version)
-      ssl_version = socket_io.ssl_version
-
-      case ssl_version
-      when /TLSv([\d\.]+)/
-        version = Gem::Version.new($1)
-        if version < Gem::Version.new("1.2")
-          Bundler.ui.warn \
-            "Warning: Your Ruby version is compiled against a copy of OpenSSL that is very old. " \
-            "Starting in January 2018, RubyGems.org will refuse connection requests from these " \
-            "very old versions of OpenSSL. If you will need to continue installing gems after " \
-            "January 2018, please follow this guide to upgrade: http://ruby.to/tls-outdated.",
-            :wrap => true
-        end
-      end
-    end
-  end
+  PersistentHTTP = Persistent::Net::HTTP::Persistent
 end
diff --git a/lib/bundler/vendored_tmpdir.rb b/lib/bundler/vendored_pub_grub.rb
index 43b4fa75fe..b36a996b29 100644
--- a/lib/bundler/vendored_tmpdir.rb
+++ b/lib/bundler/vendored_pub_grub.rb
@@ -1,4 +1,4 @@
 # frozen_string_literal: true
 
 module Bundler; end
-require_relative "vendor/tmpdir/lib/tmpdir"
+require_relative "vendor/pub_grub/lib/pub_grub"
diff --git a/lib/bundler/version.rb b/lib/bundler/version.rb
index 1acb00fd3a..8ef7be935b 100644
--- a/lib/bundler/version.rb
+++ b/lib/bundler/version.rb
@@ -1,9 +1,13 @@
 # frozen_string_literal: false
 
 module Bundler
-  VERSION = "2.4.0.dev".freeze
+  VERSION = "2.4.19".freeze
 
   def self.bundler_major_version
     @bundler_major_version ||= VERSION.split(".").first.to_i
   end
+
+  def self.gem_version
+    @gem_version ||= Gem::Version.create(VERSION)
+  end
 end
diff --git a/lib/bundler/version_ranges.rb b/lib/bundler/version_ranges.rb
deleted file mode 100644
index 12a956d6a0..0000000000
--- a/lib/bundler/version_ranges.rb
+++ /dev/null
@@ -1,122 +0,0 @@
-# frozen_string_literal: true
-
-module Bundler
-  module VersionRanges
-    NEq = Struct.new(:version)
-    ReqR = Struct.new(:left, :right)
-    class ReqR
-      Endpoint = Struct.new(:version, :inclusive) do
-        def <=>(other)
-          if version.equal?(INFINITY)
-            return 0 if other.version.equal?(INFINITY)
-            return 1
-          elsif other.version.equal?(INFINITY)
-            return -1
-          end
-
-          comp = version <=> other.version
-          return comp unless comp.zero?
-
-          if inclusive && !other.inclusive
-            1
-          elsif !inclusive && other.inclusive
-            -1
-          else
-            0
-          end
-        end
-      end
-
-      def to_s
-        "#{left.inclusive ? "[" : "("}#{left.version}, #{right.version}#{right.inclusive ? "]" : ")"}"
-      end
-      INFINITY = begin
-        inf = Object.new
-        def inf.to_s
-          "∞"
-        end
-        def inf.<=>(other)
-          return 0 if other.equal?(self)
-          1
-        end
-        inf.freeze
-      end
-      ZERO = Gem::Version.new("0.a")
-
-      def cover?(v)
-        return false if left.inclusive && left.version > v
-        return false if !left.inclusive && left.version >= v
-
-        if right.version != INFINITY
-          return false if right.inclusive && right.version < v
-          return false if !right.inclusive && right.version <= v
-        end
-
-        true
-      end
-
-      def empty?
-        left.version == right.version && !(left.inclusive && right.inclusive)
-      end
-
-      def single?
-        left.version == right.version
-      end
-
-      def <=>(other)
-        return -1 if other.equal?(INFINITY)
-
-        comp = left <=> other.left
-        return comp unless comp.zero?
-
-        right <=> other.right
-      end
-
-      UNIVERSAL = ReqR.new(ReqR::Endpoint.new(Gem::Version.new("0.a"), true), ReqR::Endpoint.new(ReqR::INFINITY, false)).freeze
-    end
-
-    def self.for_many(requirements)
-      requirements = requirements.map(&:requirements).flatten(1).map {|r| r.join(" ") }
-      requirements << ">= 0.a" if requirements.empty?
-      requirement = Gem::Requirement.new(requirements)
-      self.for(requirement)
-    end
-
-    def self.for(requirement)
-      ranges = requirement.requirements.map do |op, v|
-        case op
-        when "=" then ReqR.new(ReqR::Endpoint.new(v, true), ReqR::Endpoint.new(v, true))
-        when "!=" then NEq.new(v)
-        when ">=" then ReqR.new(ReqR::Endpoint.new(v, true), ReqR::Endpoint.new(ReqR::INFINITY, false))
-        when ">" then ReqR.new(ReqR::Endpoint.new(v, false), ReqR::Endpoint.new(ReqR::INFINITY, false))
-        when "<" then ReqR.new(ReqR::Endpoint.new(ReqR::ZERO, true), ReqR::Endpoint.new(v, false))
-        when "<=" then ReqR.new(ReqR::Endpoint.new(ReqR::ZERO, true), ReqR::Endpoint.new(v, true))
-        when "~>" then ReqR.new(ReqR::Endpoint.new(v, true), ReqR::Endpoint.new(v.bump, false))
-        else raise "unknown version op #{op} in requirement #{requirement}"
-        end
-      end.uniq
-      ranges, neqs = ranges.partition {|r| !r.is_a?(NEq) }
-
-      [ranges.sort, neqs.map(&:version)]
-    end
-
-    def self.empty?(ranges, neqs)
-      !ranges.reduce(ReqR::UNIVERSAL) do |last_range, curr_range|
-        next false unless last_range
-        next false if curr_range.single? && neqs.include?(curr_range.left.version)
-        next curr_range if last_range.right.version == ReqR::INFINITY
-        case last_range.right.version <=> curr_range.left.version
-        # higher
-        when 1 then next ReqR.new(curr_range.left, last_range.right)
-        # equal
-        when 0
-          if last_range.right.inclusive && curr_range.left.inclusive && !neqs.include?(curr_range.left.version)
-            ReqR.new(curr_range.left, [curr_range.right, last_range.right].max)
-          end
-        # lower
-        when -1 then next false
-        end
-      end
-    end
-  end
-end
diff --git a/lib/bundler/worker.rb b/lib/bundler/worker.rb
index 5e4ee21c51..3ebd6f01db 100644
--- a/lib/bundler/worker.rb
+++ b/lib/bundler/worker.rb
@@ -87,14 +87,12 @@ module Bundler
       creation_errors = []
 
       @threads = Array.new(@size) do |i|
-        begin
-          Thread.start { process_queue(i) }.tap do |thread|
-            thread.name = "#{name} Worker ##{i}" if thread.respond_to?(:name=)
-          end
-        rescue ThreadError => e
-          creation_errors << e
-          nil
+        Thread.start { process_queue(i) }.tap do |thread|
+          thread.name = "#{name} Worker ##{i}" if thread.respond_to?(:name=)
         end
+      rescue ThreadError => e
+        creation_errors << e
+        nil
       end.compact
 
       add_interrupt_handler unless @threads.empty?
diff --git a/lib/cgi.rb b/lib/cgi.rb
index affe8fd3fc..7dc3a64941 100644
--- a/lib/cgi.rb
+++ b/lib/cgi.rb
@@ -288,7 +288,7 @@
 #
 
 class CGI
-  VERSION = "0.3.2"
+  VERSION = "0.3.7"
 end
 
 require 'cgi/core'
diff --git a/lib/cgi/cgi.gemspec b/lib/cgi/cgi.gemspec
index 3ba62b93f6..381c55a5ca 100644
--- a/lib/cgi/cgi.gemspec
+++ b/lib/cgi/cgi.gemspec
@@ -22,10 +22,21 @@ Gem::Specification.new do |spec|
   spec.metadata["homepage_uri"] = spec.homepage
   spec.metadata["source_code_uri"] = spec.homepage
 
-  spec.files         = Dir.chdir(File.expand_path('..', __FILE__)) do
-    `git ls-files -z 2>/dev/null`.split("\x0").reject { |f| f.match(%r{\A(?:(?:test|spec|features)/|\.git)}) }
-  end
-  spec.extensions    = ["ext/cgi/escape/extconf.rb"]
   spec.executables   = []
+
+  spec.files = [
+    "LICENSE.txt",
+    "README.md",
+    *Dir["lib{.rb,/**/*.rb}", "bin/*"]  ]
+
   spec.require_paths = ["lib"]
+
+  if Gem::Platform === spec.platform and spec.platform =~ 'java' or RUBY_ENGINE == 'jruby'
+    spec.platform = 'java'
+    spec.require_paths << "ext/java/org/jruby/ext/cgi/escape/lib"
+    spec.files += Dir["ext/java/**/*.{rb}", "lib/cgi/escape.jar"]
+  else
+    spec.files += Dir["ext/cgi/**/*.{rb,c,h,sh}", "ext/cgi/escape/depend", "lib/cgi/escape.so"]
+    spec.extensions    = ["ext/cgi/escape/extconf.rb"]
+  end
 end
diff --git a/lib/cgi/cookie.rb b/lib/cgi/cookie.rb
index 6b0d89ca3b..1c4ef6a600 100644
--- a/lib/cgi/cookie.rb
+++ b/lib/cgi/cookie.rb
@@ -40,6 +40,10 @@ class CGI
   class Cookie < Array
     @@accept_charset="UTF-8" unless defined?(@@accept_charset)
 
+    TOKEN_RE = %r"\A[[!-~]&&[^()<>@,;:\\\"/?=\[\]{}]]+\z"
+    PATH_VALUE_RE = %r"\A[[ -~]&&[^;]]*\z"
+    DOMAIN_VALUE_RE = %r"\A\.?(?<label>(?!-)[-A-Za-z0-9]+(?<!-))(?:\.\g<label>)*\z"
+
     # Create a new CGI::Cookie object.
     #
     # :call-seq:
@@ -72,8 +76,8 @@ class CGI
       @domain = nil
       @expires = nil
       if name.kind_of?(String)
-        @name = name
-        @path = (%r|\A(.*/)| =~ ENV["SCRIPT_NAME"] ? $1 : "")
+        self.name = name
+        self.path = (%r|\A(.*/)| =~ ENV["SCRIPT_NAME"] ? $1 : "")
         @secure = false
         @httponly = false
         return super(value)
@@ -84,11 +88,11 @@ class CGI
         raise ArgumentError, "`name' required"
       end
 
-      @name = options["name"]
+      self.name = options["name"]
       value = Array(options["value"])
       # simple support for IE
-      @path = options["path"] || (%r|\A(.*/)| =~ ENV["SCRIPT_NAME"] ? $1 : "")
-      @domain = options["domain"]
+      self.path = options["path"] || (%r|\A(.*/)| =~ ENV["SCRIPT_NAME"] ? $1 : "")
+      self.domain = options["domain"]
       @expires = options["expires"]
       @secure = options["secure"] == true
       @httponly = options["httponly"] == true
@@ -97,11 +101,35 @@ class CGI
     end
 
     # Name of this cookie, as a +String+
-    attr_accessor :name
+    attr_reader :name
+    # Set name of this cookie
+    def name=(str)
+      if str and !TOKEN_RE.match?(str)
+        raise ArgumentError, "invalid name: #{str.dump}"
+      end
+      @name = str
+    end
+
     # Path for which this cookie applies, as a +String+
-    attr_accessor :path
+    attr_reader :path
+    # Set path for which this cookie applies
+    def path=(str)
+      if str and !PATH_VALUE_RE.match?(str)
+        raise ArgumentError, "invalid path: #{str.dump}"
+      end
+      @path = str
+    end
+
     # Domain for which this cookie applies, as a +String+
-    attr_accessor :domain
+    attr_reader :domain
+    # Set domain for which this cookie applies
+    def domain=(str)
+      if str and ((str = str.b).bytesize > 255 or !DOMAIN_VALUE_RE.match?(str))
+        raise ArgumentError, "invalid domain: #{str.dump}"
+      end
+      @domain = str
+    end
+
     # Time at which this cookie expires, as a +Time+
     attr_accessor :expires
     # True if this cookie is secure; false otherwise
@@ -162,9 +190,10 @@ class CGI
         values ||= ""
         values = values.split('&').collect{|v| CGI.unescape(v,@@accept_charset) }
         if cookies.has_key?(name)
-          values = cookies[name].value + values
+          cookies[name].concat(values)
+        else
+          cookies[name] = Cookie.new(name, *values)
         end
-        cookies[name] = Cookie.new(name, *values)
       end
 
       cookies
diff --git a/lib/cgi/core.rb b/lib/cgi/core.rb
index bec76e0749..62e606837a 100644
--- a/lib/cgi/core.rb
+++ b/lib/cgi/core.rb
@@ -188,17 +188,28 @@ class CGI
   # Using #header with the HTML5 tag maker will create a <header> element.
   alias :header :http_header
 
+  def _no_crlf_check(str)
+    if str
+      str = str.to_s
+      raise "A HTTP status or header field must not include CR and LF" if str =~ /[\r\n]/
+      str
+    else
+      nil
+    end
+  end
+  private :_no_crlf_check
+
   def _header_for_string(content_type) #:nodoc:
     buf = ''.dup
     if nph?()
-      buf << "#{$CGI_ENV['SERVER_PROTOCOL'] || 'HTTP/1.0'} 200 OK#{EOL}"
+      buf << "#{_no_crlf_check($CGI_ENV['SERVER_PROTOCOL']) || 'HTTP/1.0'} 200 OK#{EOL}"
       buf << "Date: #{CGI.rfc1123_date(Time.now)}#{EOL}"
-      buf << "Server: #{$CGI_ENV['SERVER_SOFTWARE']}#{EOL}"
+      buf << "Server: #{_no_crlf_check($CGI_ENV['SERVER_SOFTWARE'])}#{EOL}"
       buf << "Connection: close#{EOL}"
     end
-    buf << "Content-Type: #{content_type}#{EOL}"
+    buf << "Content-Type: #{_no_crlf_check(content_type)}#{EOL}"
     if @output_cookies
-      @output_cookies.each {|cookie| buf << "Set-Cookie: #{cookie}#{EOL}" }
+      @output_cookies.each {|cookie| buf << "Set-Cookie: #{_no_crlf_check(cookie)}#{EOL}" }
     end
     return buf
   end # _header_for_string
@@ -213,9 +224,9 @@ class CGI
     ## NPH
     options.delete('nph') if defined?(MOD_RUBY)
     if options.delete('nph') || nph?()
-      protocol = $CGI_ENV['SERVER_PROTOCOL'] || 'HTTP/1.0'
+      protocol = _no_crlf_check($CGI_ENV['SERVER_PROTOCOL']) || 'HTTP/1.0'
       status = options.delete('status')
-      status = HTTP_STATUS[status] || status || '200 OK'
+      status = HTTP_STATUS[status] || _no_crlf_check(status) || '200 OK'
       buf << "#{protocol} #{status}#{EOL}"
       buf << "Date: #{CGI.rfc1123_date(Time.now)}#{EOL}"
       options['server'] ||= $CGI_ENV['SERVER_SOFTWARE'] || ''
@@ -223,38 +234,38 @@ class CGI
     end
     ## common headers
     status = options.delete('status')
-    buf << "Status: #{HTTP_STATUS[status] || status}#{EOL}" if status
+    buf << "Status: #{HTTP_STATUS[status] || _no_crlf_check(status)}#{EOL}" if status
     server = options.delete('server')
-    buf << "Server: #{server}#{EOL}" if server
+    buf << "Server: #{_no_crlf_check(server)}#{EOL}" if server
     connection = options.delete('connection')
-    buf << "Connection: #{connection}#{EOL}" if connection
+    buf << "Connection: #{_no_crlf_check(connection)}#{EOL}" if connection
     type = options.delete('type')
-    buf << "Content-Type: #{type}#{EOL}" #if type
+    buf << "Content-Type: #{_no_crlf_check(type)}#{EOL}" #if type
     length = options.delete('length')
-    buf << "Content-Length: #{length}#{EOL}" if length
+    buf << "Content-Length: #{_no_crlf_check(length)}#{EOL}" if length
     language = options.delete('language')
-    buf << "Content-Language: #{language}#{EOL}" if language
+    buf << "Content-Language: #{_no_crlf_check(language)}#{EOL}" if language
     expires = options.delete('expires')
     buf << "Expires: #{CGI.rfc1123_date(expires)}#{EOL}" if expires
     ## cookie
     if cookie = options.delete('cookie')
       case cookie
       when String, Cookie
-        buf << "Set-Cookie: #{cookie}#{EOL}"
+        buf << "Set-Cookie: #{_no_crlf_check(cookie)}#{EOL}"
       when Array
         arr = cookie
-        arr.each {|c| buf << "Set-Cookie: #{c}#{EOL}" }
+        arr.each {|c| buf << "Set-Cookie: #{_no_crlf_check(c)}#{EOL}" }
       when Hash
         hash = cookie
-        hash.each_value {|c| buf << "Set-Cookie: #{c}#{EOL}" }
+        hash.each_value {|c| buf << "Set-Cookie: #{_no_crlf_check(c)}#{EOL}" }
       end
     end
     if @output_cookies
-      @output_cookies.each {|c| buf << "Set-Cookie: #{c}#{EOL}" }
+      @output_cookies.each {|c| buf << "Set-Cookie: #{_no_crlf_check(c)}#{EOL}" }
     end
     ## other headers
     options.each do |key, value|
-      buf << "#{key}: #{value}#{EOL}"
+      buf << "#{_no_crlf_check(key)}: #{_no_crlf_check(value)}#{EOL}"
     end
     return buf
   end # _header_for_hash
diff --git a/lib/cgi/util.rb b/lib/cgi/util.rb
index 55e61bf984..ce77a0ccd5 100644
--- a/lib/cgi/util.rb
+++ b/lib/cgi/util.rb
@@ -5,24 +5,57 @@ class CGI
   extend Util
 end
 module CGI::Util
-  @@accept_charset="UTF-8" unless defined?(@@accept_charset)
-  # URL-encode a string.
+  @@accept_charset = Encoding::UTF_8 unless defined?(@@accept_charset)
+
+  # URL-encode a string into application/x-www-form-urlencoded.
+  # Space characters (+" "+) are encoded with plus signs (+"+"+)
   #   url_encoded_string = CGI.escape("'Stop!' said Fred")
   #      # => "%27Stop%21%27+said+Fred"
   def escape(string)
     encoding = string.encoding
-    string.b.gsub(/([^ a-zA-Z0-9_.\-~]+)/) do |m|
+    buffer = string.b
+    buffer.gsub!(/([^ a-zA-Z0-9_.\-~]+)/) do |m|
       '%' + m.unpack('H2' * m.bytesize).join('%').upcase
-    end.tr(' ', '+').force_encoding(encoding)
+    end
+    buffer.tr!(' ', '+')
+    buffer.force_encoding(encoding)
   end
 
-  # URL-decode a string with encoding(optional).
+  # URL-decode an application/x-www-form-urlencoded string with encoding(optional).
   #   string = CGI.unescape("%27Stop%21%27+said+Fred")
   #      # => "'Stop!' said Fred"
-  def unescape(string,encoding=@@accept_charset)
-    str=string.tr('+', ' ').b.gsub(/((?:%[0-9a-fA-F]{2})+)/) do |m|
+  def unescape(string, encoding = @@accept_charset)
+    str = string.tr('+', ' ')
+    str = str.b
+    str.gsub!(/((?:%[0-9a-fA-F]{2})+)/) do |m|
+      [m.delete('%')].pack('H*')
+    end
+    str.force_encoding(encoding)
+    str.valid_encoding? ? str : str.force_encoding(string.encoding)
+  end
+
+  # URL-encode a string following RFC 3986
+  # Space characters (+" "+) are encoded with (+"%20"+)
+  #   url_encoded_string = CGI.escape("'Stop!' said Fred")
+  #      # => "%27Stop%21%27%20said%20Fred"
+  def escapeURIComponent(string)
+    encoding = string.encoding
+    buffer = string.b
+    buffer.gsub!(/([^a-zA-Z0-9_.\-~]+)/) do |m|
+      '%' + m.unpack('H2' * m.bytesize).join('%').upcase
+    end
+    buffer.force_encoding(encoding)
+  end
+
+  # URL-decode a string following RFC 3986 with encoding(optional).
+  #   string = CGI.unescape("%27Stop%21%27+said%20Fred")
+  #      # => "'Stop!'+said Fred"
+  def unescapeURIComponent(string, encoding = @@accept_charset)
+    str = string.b
+    str.gsub!(/((?:%[0-9a-fA-F]{2})+)/) do |m|
       [m.delete('%')].pack('H*')
-    end.force_encoding(encoding)
+    end
+    str.force_encoding(encoding)
     str.valid_encoding? ? str : str.force_encoding(string.encoding)
   end
 
@@ -145,7 +178,7 @@ module CGI::Util
   def escapeElement(string, *elements)
     elements = elements[0] if elements[0].kind_of?(Array)
     unless elements.empty?
-      string.gsub(/<\/?(?:#{elements.join("|")})(?!\w)(?:.|\n)*?>/i) do
+      string.gsub(/<\/?(?:#{elements.join("|")})\b[^<>]*+>?/im) do
         CGI.escapeHTML($&)
       end
     else
@@ -165,7 +198,7 @@ module CGI::Util
   def unescapeElement(string, *elements)
     elements = elements[0] if elements[0].kind_of?(Array)
     unless elements.empty?
-      string.gsub(/&lt;\/?(?:#{elements.join("|")})(?!\w)(?:.|\n)*?&gt;/i) do
+      string.gsub(/&lt;\/?(?:#{elements.join("|")})\b(?>[^&]+|&(?![gl]t;)\w+;)*(?:&gt;)?/im) do
         unescapeHTML($&)
       end
     else
diff --git a/lib/csv.rb b/lib/csv.rb
index 06a490f34c..0307033941 100644
--- a/lib/csv.rb
+++ b/lib/csv.rb
@@ -48,7 +48,7 @@
 #
 # === Interface
 #
-# * CSV now uses Hash-style parameters to set options.
+# * CSV now uses keyword parameters to set options.
 # * CSV no longer has generate_row() or parse_row().
 # * The old CSV's Reader and Writer classes have been dropped.
 # * CSV::open() is now more like Ruby's open().
@@ -95,16 +95,24 @@ require "stringio"
 
 require_relative "csv/fields_converter"
 require_relative "csv/input_record_separator"
-require_relative "csv/match_p"
 require_relative "csv/parser"
 require_relative "csv/row"
 require_relative "csv/table"
 require_relative "csv/writer"
 
-using CSV::MatchP if CSV.const_defined?(:MatchP)
-
 # == \CSV
-# \CSV (comma-separated variables) data is a text representation of a table:
+#
+# === In a Hurry?
+#
+# If you are familiar with \CSV data and have a particular task in mind,
+# you may want to go directly to the:
+# - {Recipes for CSV}[doc/csv/recipes/recipes_rdoc.html].
+#
+# Otherwise, read on here, about the API: classes, methods, and constants.
+#
+# === \CSV Data
+#
+# \CSV (comma-separated values) data is a text representation of a table:
 # - A _row_ _separator_ delimits table rows.
 #   A common row separator is the newline character <tt>"\n"</tt>.
 # - A _column_ _separator_ delimits fields in a row.
@@ -346,7 +354,9 @@ using CSV::MatchP if CSV.const_defined?(:MatchP)
 # - +row_sep+: Specifies the row separator; used to delimit rows.
 # - +col_sep+: Specifies the column separator; used to delimit fields.
 # - +quote_char+: Specifies the quote character; used to quote fields.
-# - +field_size_limit+: Specifies the maximum field size allowed.
+# - +field_size_limit+: Specifies the maximum field size + 1 allowed.
+#   Deprecated since 3.2.3. Use +max_field_size+ instead.
+# - +max_field_size+: Specifies the maximum field size allowed.
 # - +converters+: Specifies the field converters to be used.
 # - +unconverted_fields+: Specifies whether unconverted fields are to be available.
 # - +headers+: Specifies whether data contains headers,
@@ -703,7 +713,7 @@ using CSV::MatchP if CSV.const_defined?(:MatchP)
 # Header converters operate only on headers (and not on other rows).
 #
 # There are three ways to use header \converters;
-# these examples use built-in header converter +:dowhcase+,
+# these examples use built-in header converter +:downcase+,
 # which downcases each parsed header.
 #
 # - Option +header_converters+ with a singleton parsing method:
@@ -853,8 +863,9 @@ class CSV
   # <b><tt>index</tt></b>::  The zero-based index of the field in its row.
   # <b><tt>line</tt></b>::   The line of the data source this row is from.
   # <b><tt>header</tt></b>:: The header for the column, when available.
+  # <b><tt>quoted?</tt></b>:: True or false, whether the original value is quoted or not.
   #
-  FieldInfo = Struct.new(:index, :line, :header)
+  FieldInfo = Struct.new(:index, :line, :header, :quoted?)
 
   # A Regexp used to find and convert some common Date formats.
   DateMatcher     = / \A(?: (\w+,?\s+)?\w+\s+\d{1,2},?\s+\d{2,4} |
@@ -862,10 +873,9 @@ class CSV
   # A Regexp used to find and convert some common DateTime formats.
   DateTimeMatcher =
     / \A(?: (\w+,?\s+)?\w+\s+\d{1,2}\s+\d{1,2}:\d{1,2}:\d{1,2},?\s+\d{2,4} |
-            \d{4}-\d{2}-\d{2}\s\d{2}:\d{2}:\d{2} |
-            # ISO-8601
+            # ISO-8601 and RFC-3339 (space instead of T) recognized by DateTime.parse
             \d{4}-\d{2}-\d{2}
-              (?:T\d{2}:\d{2}(?::\d{2}(?:\.\d+)?(?:[+-]\d{2}(?::\d{2})|Z)?)?)?
+              (?:[T\s]\d{2}:\d{2}(?::\d{2}(?:\.\d+)?(?:[+-]\d{2}(?::\d{2})|Z)?)?)?
         )\z /x
 
   # The encoding used by all converters.
@@ -915,7 +925,8 @@ class CSV
     symbol:   lambda { |h|
       h.encode(ConverterEncoding).downcase.gsub(/[^\s\w]+/, "").strip.
                                            gsub(/\s+/, "_").to_sym
-    }
+    },
+    symbol_raw: lambda { |h| h.encode(ConverterEncoding).to_sym }
   }
 
   # Default values for method options.
@@ -926,6 +937,7 @@ class CSV
     quote_char:         '"',
     # For parsing.
     field_size_limit:   nil,
+    max_field_size:     nil,
     converters:         nil,
     unconverted_fields: nil,
     headers:            false,
@@ -993,7 +1005,7 @@ class CSV
     def instance(data = $stdout, **options)
       # create a _signature_ for this method call, data object and options
       sig = [data.object_id] +
-            options.values_at(*DEFAULT_OPTIONS.keys.sort_by { |sym| sym.to_s })
+            options.values_at(*DEFAULT_OPTIONS.keys)
 
       # fetch or create the instance for this signature
       @@instances ||= Hash.new
@@ -1007,65 +1019,190 @@ class CSV
     end
 
     # :call-seq:
-    #   filter(**options) {|row| ... }
-    #   filter(in_string, **options) {|row| ... }
-    #   filter(in_io, **options) {|row| ... }
-    #   filter(in_string, out_string, **options) {|row| ... }
-    #   filter(in_string, out_io, **options) {|row| ... }
-    #   filter(in_io, out_string, **options) {|row| ... }
-    #   filter(in_io, out_io, **options) {|row| ... }
-    #
-    # Reads \CSV input and writes \CSV output.
-    #
-    # For each input row:
-    # - Forms the data into:
-    #   - A CSV::Row object, if headers are in use.
-    #   - An \Array of Arrays, otherwise.
-    # - Calls the block with that object.
-    # - Appends the block's return value to the output.
+    #   filter(in_string_or_io, **options) {|row| ... } -> array_of_arrays or csv_table
+    #   filter(in_string_or_io, out_string_or_io, **options) {|row| ... } -> array_of_arrays or csv_table
+    #   filter(**options) {|row| ... } -> array_of_arrays or csv_table
     #
-    # Arguments:
-    # * \CSV source:
-    #   * Argument +in_string+, if given, should be a \String object;
-    #     it will be put into a new StringIO object positioned at the beginning.
-    #   * Argument +in_io+, if given, should be an IO object that is
-    #     open for reading; on return, the IO object will be closed.
-    #   * If neither  +in_string+ nor +in_io+ is given,
-    #     the input stream defaults to {ARGF}[https://ruby-doc.org/core/ARGF.html].
-    # * \CSV output:
-    #   * Argument +out_string+, if given, should be a \String object;
-    #     it will be put into a new StringIO object positioned at the beginning.
-    #   * Argument +out_io+, if given, should be an IO object that is
-    #     ppen for writing; on return, the IO object will be closed.
-    #   * If neither +out_string+ nor +out_io+ is given,
-    #     the output stream defaults to <tt>$stdout</tt>.
-    # * Argument +options+ should be keyword arguments.
-    #   - Each argument name that is prefixed with +in_+ or +input_+
-    #     is stripped of its prefix and is treated as an option
-    #     for parsing the input.
-    #     Option +input_row_sep+ defaults to <tt>$INPUT_RECORD_SEPARATOR</tt>.
-    #   - Each argument name that is prefixed with +out_+ or +output_+
-    #     is stripped of its prefix and is treated as an option
-    #     for generating the output.
-    #     Option +output_row_sep+ defaults to <tt>$INPUT_RECORD_SEPARATOR</tt>.
-    #   - Each argument not prefixed as above is treated as an option
-    #     both for parsing the input and for generating the output.
-    #   - See {Options for Parsing}[#class-CSV-label-Options+for+Parsing]
-    #     and {Options for Generating}[#class-CSV-label-Options+for+Generating].
+    # - Parses \CSV from a source (\String, \IO stream, or ARGF).
+    # - Calls the given block with each parsed row:
+    #   - Without headers, each row is an \Array.
+    #   - With headers, each row is a CSV::Row.
+    # - Generates \CSV to an output (\String, \IO stream, or STDOUT).
+    # - Returns the parsed source:
+    #   - Without headers, an \Array of \Arrays.
+    #   - With headers, a CSV::Table.
     #
-    # Example:
-    #   in_string = "foo,0\nbar,1\nbaz,2\n"
+    # When +in_string_or_io+ is given, but not +out_string_or_io+,
+    # parses from the given +in_string_or_io+
+    # and generates to STDOUT.
+    #
+    # \String input without headers:
+    #
+    #   in_string = "foo,0\nbar,1\nbaz,2"
+    #   CSV.filter(in_string) do |row|
+    #     row[0].upcase!
+    #     row[1] = - row[1].to_i
+    #   end # => [["FOO", 0], ["BAR", -1], ["BAZ", -2]]
+    #
+    # Output (to STDOUT):
+    #
+    #   FOO,0
+    #   BAR,-1
+    #   BAZ,-2
+    #
+    # \String input with headers:
+    #
+    #   in_string = "Name,Value\nfoo,0\nbar,1\nbaz,2"
+    #   CSV.filter(in_string, headers: true) do |row|
+    #     row[0].upcase!
+    #     row[1] = - row[1].to_i
+    #   end # => #<CSV::Table mode:col_or_row row_count:4>
+    #
+    # Output (to STDOUT):
+    #
+    #   Name,Value
+    #   FOO,0
+    #   BAR,-1
+    #   BAZ,-2
+    #
+    # \IO stream input without headers:
+    #
+    #   File.write('t.csv', "foo,0\nbar,1\nbaz,2")
+    #   File.open('t.csv') do |in_io|
+    #     CSV.filter(in_io) do |row|
+    #       row[0].upcase!
+    #       row[1] = - row[1].to_i
+    #     end
+    #   end # => [["FOO", 0], ["BAR", -1], ["BAZ", -2]]
+    #
+    # Output (to STDOUT):
+    #
+    #   FOO,0
+    #   BAR,-1
+    #   BAZ,-2
+    #
+    # \IO stream input with headers:
+    #
+    #   File.write('t.csv', "Name,Value\nfoo,0\nbar,1\nbaz,2")
+    #   File.open('t.csv') do |in_io|
+    #     CSV.filter(in_io, headers: true) do |row|
+    #       row[0].upcase!
+    #       row[1] = - row[1].to_i
+    #     end
+    #   end # => #<CSV::Table mode:col_or_row row_count:4>
+    #
+    # Output (to STDOUT):
+    #
+    #   Name,Value
+    #   FOO,0
+    #   BAR,-1
+    #   BAZ,-2
+    #
+    # When both +in_string_or_io+ and +out_string_or_io+ are given,
+    # parses from +in_string_or_io+ and generates to +out_string_or_io+.
+    #
+    # \String output without headers:
+    #
+    #   in_string = "foo,0\nbar,1\nbaz,2"
     #   out_string = ''
     #   CSV.filter(in_string, out_string) do |row|
-    #     row[0] = row[0].upcase
-    #     row[1] *= 4
-    #   end
-    #   out_string # => "FOO,0000\nBAR,1111\nBAZ,2222\n"
+    #     row[0].upcase!
+    #     row[1] = - row[1].to_i
+    #   end # => [["FOO", 0], ["BAR", -1], ["BAZ", -2]]
+    #   out_string # => "FOO,0\nBAR,-1\nBAZ,-2\n"
+    #
+    # \String output with headers:
+    #
+    #   in_string = "Name,Value\nfoo,0\nbar,1\nbaz,2"
+    #   out_string = ''
+    #   CSV.filter(in_string, out_string, headers: true) do |row|
+    #     row[0].upcase!
+    #     row[1] = - row[1].to_i
+    #   end # => #<CSV::Table mode:col_or_row row_count:4>
+    #   out_string # => "Name,Value\nFOO,0\nBAR,-1\nBAZ,-2\n"
+    #
+    # \IO stream output without headers:
+    #
+    #   in_string = "foo,0\nbar,1\nbaz,2"
+    #   File.open('t.csv', 'w') do |out_io|
+    #     CSV.filter(in_string, out_io) do |row|
+    #       row[0].upcase!
+    #       row[1] = - row[1].to_i
+    #     end
+    #   end # => [["FOO", 0], ["BAR", -1], ["BAZ", -2]]
+    #   File.read('t.csv') # => "FOO,0\nBAR,-1\nBAZ,-2\n"
+    #
+    # \IO stream output with headers:
+    #
+    #   in_string = "Name,Value\nfoo,0\nbar,1\nbaz,2"
+    #   File.open('t.csv', 'w') do |out_io|
+    #     CSV.filter(in_string, out_io, headers: true) do |row|
+    #       row[0].upcase!
+    #       row[1] = - row[1].to_i
+    #     end
+    #   end # => #<CSV::Table mode:col_or_row row_count:4>
+    #   File.read('t.csv') # => "Name,Value\nFOO,0\nBAR,-1\nBAZ,-2\n"
+    #
+    # When neither +in_string_or_io+ nor +out_string_or_io+ given,
+    # parses from {ARGF}[rdoc-ref:ARGF]
+    # and generates to STDOUT.
+    #
+    # Without headers:
+    #
+    #   # Put Ruby code into a file.
+    #   ruby = <<-EOT
+    #     require 'csv'
+    #     CSV.filter do |row|
+    #       row[0].upcase!
+    #       row[1] = - row[1].to_i
+    #     end
+    #   EOT
+    #   File.write('t.rb', ruby)
+    #   # Put some CSV into a file.
+    #   File.write('t.csv', "foo,0\nbar,1\nbaz,2")
+    #   # Run the Ruby code with CSV filename as argument.
+    #   system(Gem.ruby, "t.rb", "t.csv")
+    #
+    # Output (to STDOUT):
+    #
+    #   FOO,0
+    #   BAR,-1
+    #   BAZ,-2
+    #
+    # With headers:
+    #
+    #   # Put Ruby code into a file.
+    #   ruby = <<-EOT
+    #     require 'csv'
+    #     CSV.filter(headers: true) do |row|
+    #       row[0].upcase!
+    #       row[1] = - row[1].to_i
+    #     end
+    #   EOT
+    #   File.write('t.rb', ruby)
+    #   # Put some CSV into a file.
+    #   File.write('t.csv', "Name,Value\nfoo,0\nbar,1\nbaz,2")
+    #   # Run the Ruby code with CSV filename as argument.
+    #   system(Gem.ruby, "t.rb", "t.csv")
+    #
+    # Output (to STDOUT):
+    #
+    #   Name,Value
+    #   FOO,0
+    #   BAR,-1
+    #   BAZ,-2
+    #
+    # Arguments:
+    #
+    # * Argument +in_string_or_io+ must be a \String or an \IO stream.
+    # * Argument +out_string_or_io+ must be a \String or an \IO stream.
+    # * Arguments <tt>**options</tt> must be keyword options.
+    #   See {Options for Parsing}[#class-CSV-label-Options+for+Parsing].
     def filter(input=nil, output=nil, **options)
       # parse options for input, output, or both
       in_options, out_options = Hash.new, {row_sep: InputRecordSeparator.value}
       options.each do |key, value|
-        case key.to_s
+        case key
         when /\Ain(?:put)?_(.+)\Z/
           in_options[$1.to_sym] = value
         when /\Aout(?:put)?_(.+)\Z/
@@ -1107,111 +1244,90 @@ class CSV
 
     #
     # :call-seq:
-    #   foreach(path, mode='r', **options) {|row| ... )
-    #   foreach(io, mode='r', **options {|row| ... )
-    #   foreach(path, mode='r', headers: ..., **options) {|row| ... )
-    #   foreach(io, mode='r', headers: ..., **options {|row| ... )
-    #   foreach(path, mode='r', **options) -> new_enumerator
-    #   foreach(io, mode='r', **options -> new_enumerator
+    #   foreach(path_or_io, mode='r', **options) {|row| ... )
+    #   foreach(path_or_io, mode='r', **options) -> new_enumerator
     #
-    # Calls the block with each row read from source +path+ or +io+.
+    # Calls the block with each row read from source +path_or_io+.
     #
-    # * Argument +path+, if given, must be the path to a file.
-    # :include: ../doc/csv/arguments/io.rdoc
-    # * Argument +mode+, if given, must be a \File mode
-    #   See {Open Mode}[IO.html#method-c-new-label-Open+Mode].
-    # * Arguments <tt>**options</tt> must be keyword options.
-    #   See {Options for Parsing}[#class-CSV-label-Options+for+Parsing].
-    # * This method optionally accepts an additional <tt>:encoding</tt> option
-    #   that you can use to specify the Encoding of the data read from +path+ or +io+.
-    #   You must provide this unless your data is in the encoding
-    #   given by <tt>Encoding::default_external</tt>.
-    #   Parsing will use this to determine how to parse the data.
-    #   You may provide a second Encoding to
-    #   have the data transcoded as it is read. For example,
-    #     encoding: 'UTF-32BE:UTF-8'
-    #   would read +UTF-32BE+ data from the file
-    #   but transcode it to +UTF-8+ before parsing.
-    #
-    # ====== Without Option +headers+
+    # \Path input without headers:
     #
-    # Without option +headers+, returns each row as an \Array object.
-    #
-    # These examples assume prior execution of:
     #   string = "foo,0\nbar,1\nbaz,2\n"
-    #   path = 't.csv'
-    #   File.write(path, string)
+    #   in_path = 't.csv'
+    #   File.write(in_path, string)
+    #   CSV.foreach(in_path) {|row| p row }
     #
-    # Read rows from a file at +path+:
-    #   CSV.foreach(path) {|row| p row }
     # Output:
-    #   ["foo", "0"]
-    #   ["bar", "1"]
-    #   ["baz", "2"]
     #
-    # Read rows from an \IO object:
-    #   File.open(path) do |file|
-    #     CSV.foreach(file) {|row| p row }
-    #   end
-    #
-    # Output:
     #   ["foo", "0"]
     #   ["bar", "1"]
     #   ["baz", "2"]
     #
-    # Returns a new \Enumerator if no block given:
-    #   CSV.foreach(path) # => #<Enumerator: CSV:foreach("t.csv", "r")>
-    #   CSV.foreach(File.open(path)) # => #<Enumerator: CSV:foreach(#<File:t.csv>, "r")>
+    # \Path input with headers:
+    #
+    #   string = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+    #   in_path = 't.csv'
+    #   File.write(in_path, string)
+    #   CSV.foreach(in_path, headers: true) {|row| p row }
     #
-    # Issues a warning if an encoding is unsupported:
-    #   CSV.foreach(File.open(path), encoding: 'foo:bar') {|row| }
     # Output:
-    #   warning: Unsupported encoding foo ignored
-    #   warning: Unsupported encoding bar ignored
     #
-    # ====== With Option +headers+
+    #   <CSV::Row "Name":"foo" "Value":"0">
+    #   <CSV::Row "Name":"bar" "Value":"1">
+    #   <CSV::Row "Name":"baz" "Value":"2">
     #
-    # With {option +headers+}[#class-CSV-label-Option+headers],
-    # returns each row as a CSV::Row object.
+    # \IO stream input without headers:
     #
-    # These examples assume prior execution of:
-    #   string = "Name,Count\nfoo,0\nbar,1\nbaz,2\n"
+    #   string = "foo,0\nbar,1\nbaz,2\n"
     #   path = 't.csv'
     #   File.write(path, string)
-    #
-    # Read rows from a file at +path+:
-    #   CSV.foreach(path, headers: true) {|row| p row }
+    #   File.open('t.csv') do |in_io|
+    #     CSV.foreach(in_io) {|row| p row }
+    #   end
     #
     # Output:
-    #   #<CSV::Row "Name":"foo" "Count":"0">
-    #   #<CSV::Row "Name":"bar" "Count":"1">
-    #   #<CSV::Row "Name":"baz" "Count":"2">
     #
-    # Read rows from an \IO object:
-    #   File.open(path) do |file|
-    #     CSV.foreach(file, headers: true) {|row| p row }
+    #   ["foo", "0"]
+    #   ["bar", "1"]
+    #   ["baz", "2"]
+    #
+    # \IO stream input with headers:
+    #
+    #   string = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+    #   path = 't.csv'
+    #   File.write(path, string)
+    #   File.open('t.csv') do |in_io|
+    #     CSV.foreach(in_io, headers: true) {|row| p row }
     #   end
     #
     # Output:
-    #   #<CSV::Row "Name":"foo" "Count":"0">
-    #   #<CSV::Row "Name":"bar" "Count":"1">
-    #   #<CSV::Row "Name":"baz" "Count":"2">
-    #
-    # ---
     #
-    # Raises an exception if +path+ is a \String, but not the path to a readable file:
-    #   # Raises Errno::ENOENT (No such file or directory @ rb_sysopen - nosuch.csv):
-    #   CSV.foreach('nosuch.csv') {|row| }
+    #   <CSV::Row "Name":"foo" "Value":"0">
+    #   <CSV::Row "Name":"bar" "Value":"1">
+    #   <CSV::Row "Name":"baz" "Value":"2">
     #
-    # Raises an exception if +io+ is an \IO object, but not open for reading:
-    #   io = File.open(path, 'w') {|row| }
-    #   # Raises TypeError (no implicit conversion of nil into String):
-    #   CSV.foreach(io) {|row| }
+    # With no block given, returns an \Enumerator:
     #
-    # Raises an exception if +mode+ is invalid:
-    #   # Raises ArgumentError (invalid access mode nosuch):
-    #   CSV.foreach(path, 'nosuch') {|row| }
+    #   string = "foo,0\nbar,1\nbaz,2\n"
+    #   path = 't.csv'
+    #   File.write(path, string)
+    #   CSV.foreach(path) # => #<Enumerator: CSV:foreach("t.csv", "r")>
     #
+    # Arguments:
+    # * Argument +path_or_io+ must be a file path or an \IO stream.
+    # * Argument +mode+, if given, must be a \File mode
+    #   See {Open Mode}[https://ruby-doc.org/core/IO.html#method-c-new-label-Open+Mode].
+    # * Arguments <tt>**options</tt> must be keyword options.
+    #   See {Options for Parsing}[#class-CSV-label-Options+for+Parsing].
+    # * This method optionally accepts an additional <tt>:encoding</tt> option
+    #   that you can use to specify the Encoding of the data read from +path+ or +io+.
+    #   You must provide this unless your data is in the encoding
+    #   given by <tt>Encoding::default_external</tt>.
+    #   Parsing will use this to determine how to parse the data.
+    #   You may provide a second Encoding to
+    #   have the data transcoded as it is read. For example,
+    #     encoding: 'UTF-32BE:UTF-8'
+    #   would read +UTF-32BE+ data from the file
+    #   but transcode it to +UTF-8+ before parsing.
     def foreach(path, mode="r", **options, &block)
       return to_enum(__method__, path, mode, **options) unless block_given?
       open(path, mode, **options) do |csv|
@@ -1349,6 +1465,46 @@ class CSV
       (new(str, **options) << row).string
     end
 
+    # :call-seq:
+    #   CSV.generate_lines(rows)
+    #   CSV.generate_lines(rows, **options)
+    #
+    # Returns the \String created by generating \CSV from
+    # using the specified +options+.
+    #
+    # Argument +rows+ must be an \Array of row. Row is \Array of \String or \CSV::Row.
+    #
+    # Special options:
+    # * Option <tt>:row_sep</tt> defaults to <tt>"\n"</tt> on Ruby 3.0 or later
+    #   and <tt>$INPUT_RECORD_SEPARATOR</tt> (<tt>$/</tt>) otherwise.:
+    #     $INPUT_RECORD_SEPARATOR # => "\n"
+    # * This method accepts an additional option, <tt>:encoding</tt>, which sets the base
+    #   Encoding for the output. This method will try to guess your Encoding from
+    #   the first non-+nil+ field in +row+, if possible, but you may need to use
+    #   this parameter as a backup plan.
+    #
+    # For other +options+,
+    # see {Options for Generating}[#class-CSV-label-Options+for+Generating].
+    #
+    # ---
+    #
+    # Returns the \String generated from an
+    #   CSV.generate_lines([['foo', '0'], ['bar', '1'], ['baz', '2']]) # => "foo,0\nbar,1\nbaz,2\n"
+    #
+    # ---
+    #
+    # Raises an exception
+    #   # Raises NoMethodError (undefined method `each' for :foo:Symbol)
+    #   CSV.generate_lines(:foo)
+    #
+    def generate_lines(rows, **options)
+      self.generate(**options) do |csv|
+        rows.each do |row|
+          csv << row
+        end
+      end
+    end
+
     #
     # :call-seq:
     #   open(file_path, mode = "rb", **options ) -> new_csv
@@ -1357,7 +1513,7 @@ class CSV
     #   open(io, mode = "rb", **options ) { |csv| ... } -> object
     #
     # possible options elements:
-    #   hash form:
+    #   keyword form:
     #     :invalid => nil      # raise error on invalid byte sequence (default)
     #     :invalid => :replace # replace invalid byte sequence
     #     :undef => :replace   # replace undefined conversion
@@ -1424,10 +1580,14 @@ class CSV
     def open(filename, mode="r", **options)
       # wrap a File opened with the remaining +args+ with no newline
       # decorator
-      file_opts = {universal_newline: false}.merge(options)
+      file_opts = options.dup
+      unless file_opts.key?(:newline)
+        file_opts[:universal_newline] ||= false
+      end
       options.delete(:invalid)
       options.delete(:undef)
       options.delete(:replace)
+      options.delete_if {|k, _| /newline\z/.match?(k)}
 
       begin
         f = File.open(filename, mode, **file_opts)
@@ -1746,6 +1906,7 @@ class CSV
                  row_sep: :auto,
                  quote_char: '"',
                  field_size_limit: nil,
+                 max_field_size: nil,
                  converters: nil,
                  unconverted_fields: nil,
                  headers: false,
@@ -1769,8 +1930,19 @@ class CSV
     raise ArgumentError.new("Cannot parse nil as CSV") if data.nil?
 
     if data.is_a?(String)
+      if encoding
+        if encoding.is_a?(String)
+          data_external_encoding, data_internal_encoding = encoding.split(":", 2)
+          if data_internal_encoding
+            data = data.encode(data_internal_encoding, data_external_encoding)
+          else
+            data = data.dup.force_encoding(data_external_encoding)
+          end
+        else
+          data = data.dup.force_encoding(encoding)
+        end
+      end
       @io = StringIO.new(data)
-      @io.set_encoding(encoding || data.encoding)
     else
       @io = data
     end
@@ -1788,11 +1960,14 @@ class CSV
     @initial_header_converters = header_converters
     @initial_write_converters = write_converters
 
+    if max_field_size.nil? and field_size_limit
+      max_field_size = field_size_limit - 1
+    end
     @parser_options = {
       column_separator: col_sep,
       row_separator: row_sep,
       quote_character: quote_char,
-      field_size_limit: field_size_limit,
+      max_field_size: max_field_size,
       unconverted_fields: unconverted_fields,
       headers: headers,
       return_headers: return_headers,
@@ -1860,11 +2035,25 @@ class CSV
   # Returns the limit for field size; used for parsing;
   # see {Option +field_size_limit+}[#class-CSV-label-Option+field_size_limit]:
   #   CSV.new('').field_size_limit # => nil
+  #
+  # Deprecated since 3.2.3. Use +max_field_size+ instead.
   def field_size_limit
     parser.field_size_limit
   end
 
   # :call-seq:
+  #   csv.max_field_size -> integer or nil
+  #
+  # Returns the limit for field size; used for parsing;
+  # see {Option +max_field_size+}[#class-CSV-label-Option+max_field_size]:
+  #   CSV.new('').max_field_size # => nil
+  #
+  # Since 3.2.3.
+  def max_field_size
+    parser.max_field_size
+  end
+
+  # :call-seq:
   #   csv.skip_lines -> regexp or nil
   #
   # Returns the \Regexp used to identify comment lines; used for parsing;
@@ -1994,7 +2183,7 @@ class CSV
   end
 
   # :call-seq:
-  #   csv.encoding -> endcoding
+  #   csv.encoding -> encoding
   #
   # Returns the encoding used for parsing and generating;
   # see {Character Encodings (M17n or Multilingualization)}[#class-CSV-label-Character+Encodings+-28M17n+or+Multilingualization-29]:
@@ -2362,7 +2551,13 @@ class CSV
   #     p row
   #   end
   def each(&block)
-    parser_enumerator.each(&block)
+    return to_enum(__method__) unless block_given?
+    begin
+      while true
+        yield(parser_enumerator.next)
+      end
+    rescue StopIteration
+    end
   end
 
   # :call-seq:
diff --git a/lib/csv/fields_converter.rb b/lib/csv/fields_converter.rb
index b206118d99..d15977d379 100644
--- a/lib/csv/fields_converter.rb
+++ b/lib/csv/fields_converter.rb
@@ -44,7 +44,7 @@ class CSV
       @converters.empty?
     end
 
-    def convert(fields, headers, lineno)
+    def convert(fields, headers, lineno, quoted_fields)
       return fields unless need_convert?
 
       fields.collect.with_index do |field, index|
@@ -63,7 +63,8 @@ class CSV
             else
               header = nil
             end
-            field = converter[field, FieldInfo.new(index, lineno, header)]
+            quoted = quoted_fields[index]
+            field = converter[field, FieldInfo.new(index, lineno, header, quoted)]
           end
           break unless field.is_a?(String)  # short-circuit pipeline for speed
         end
diff --git a/lib/csv/input_record_separator.rb b/lib/csv/input_record_separator.rb
index bbf13479f7..7a99343c0c 100644
--- a/lib/csv/input_record_separator.rb
+++ b/lib/csv/input_record_separator.rb
@@ -4,20 +4,7 @@ require "stringio"
 class CSV
   module InputRecordSeparator
     class << self
-      is_input_record_separator_deprecated = false
-      verbose, $VERBOSE = $VERBOSE, true
-      stderr, $stderr = $stderr, StringIO.new
-      input_record_separator = $INPUT_RECORD_SEPARATOR
-      begin
-        $INPUT_RECORD_SEPARATOR = "\r\n"
-        is_input_record_separator_deprecated = (not $stderr.string.empty?)
-      ensure
-        $INPUT_RECORD_SEPARATOR = input_record_separator
-        $stderr = stderr
-        $VERBOSE = verbose
-      end
-
-      if is_input_record_separator_deprecated
+      if RUBY_VERSION >= "3.0.0"
         def value
           "\n"
         end
diff --git a/lib/csv/parser.rb b/lib/csv/parser.rb
index 7e943acf21..afb3131cd5 100644
--- a/lib/csv/parser.rb
+++ b/lib/csv/parser.rb
@@ -2,15 +2,10 @@
 
 require "strscan"
 
-require_relative "delete_suffix"
 require_relative "input_record_separator"
-require_relative "match_p"
 require_relative "row"
 require_relative "table"
 
-using CSV::DeleteSuffix if CSV.const_defined?(:DeleteSuffix)
-using CSV::MatchP if CSV.const_defined?(:MatchP)
-
 class CSV
   # Note: Don't use this class directly. This is an internal class.
   class Parser
@@ -27,6 +22,10 @@ class CSV
     class InvalidEncoding < StandardError
     end
 
+    # Raised when unexpected case is happen.
+    class UnexpectedError < StandardError
+    end
+
     #
     # CSV::Scanner receives a CSV output, scans it and return the content.
     # It also controls the life cycle of the object with its methods +keep_start+,
@@ -78,10 +77,10 @@ class CSV
     # +keep_end+, +keep_back+, +keep_drop+.
     #
     # CSV::InputsScanner.scan() tries to match with pattern at the current position.
-    # If there's a match, the scanner advances the “scan pointer� and returns the matched string.
+    # If there's a match, the scanner advances the "scan pointer" and returns the matched string.
     # Otherwise, the scanner returns nil.
     #
-    # CSV::InputsScanner.rest() returns the “rest� of the string (i.e. everything after the scan pointer).
+    # CSV::InputsScanner.rest() returns the "rest" of the string (i.e. everything after the scan pointer).
     # If there is no more data (eos? = true), it returns "".
     #
     class InputsScanner
@@ -96,11 +95,13 @@ class CSV
       end
 
       def each_line(row_separator)
+        return enum_for(__method__, row_separator) unless block_given?
         buffer = nil
         input = @scanner.rest
         position = @scanner.pos
         offset = 0
         n_row_separator_chars = row_separator.size
+        # trace(__method__, :start, line, input)
         while true
           input.each_line(row_separator) do |line|
             @scanner.pos += line.bytesize
@@ -140,25 +141,28 @@ class CSV
       end
 
       def scan(pattern)
+        # trace(__method__, pattern, :start)
         value = @scanner.scan(pattern)
+        # trace(__method__, pattern, :done, :last, value) if @last_scanner
         return value if @last_scanner
 
-        if value
-          read_chunk if @scanner.eos?
-          return value
-        else
-          nil
-        end
+        read_chunk if value and @scanner.eos?
+        # trace(__method__, pattern, :done, value)
+        value
       end
 
       def scan_all(pattern)
+        # trace(__method__, pattern, :start)
         value = @scanner.scan(pattern)
+        # trace(__method__, pattern, :done, :last, value) if @last_scanner
         return value if @last_scanner
 
         return nil if value.nil?
         while @scanner.eos? and read_chunk and (sub_value = @scanner.scan(pattern))
+          # trace(__method__, pattern, :sub, sub_value)
           value << sub_value
         end
+        # trace(__method__, pattern, :done, value)
         value
       end
 
@@ -167,68 +171,126 @@ class CSV
       end
 
       def keep_start
-        @keeps.push([@scanner.pos, nil])
+        # trace(__method__, :start)
+        adjust_last_keep
+        @keeps.push([@scanner, @scanner.pos, nil])
+        # trace(__method__, :done)
       end
 
       def keep_end
-        start, buffer = @keeps.pop
-        keep = @scanner.string.byteslice(start, @scanner.pos - start)
+        # trace(__method__, :start)
+        scanner, start, buffer = @keeps.pop
+        if scanner == @scanner
+          keep = @scanner.string.byteslice(start, @scanner.pos - start)
+        else
+          keep = @scanner.string.byteslice(0, @scanner.pos)
+        end
         if buffer
           buffer << keep
           keep = buffer
         end
+        # trace(__method__, :done, keep)
         keep
       end
 
       def keep_back
-        start, buffer = @keeps.pop
+        # trace(__method__, :start)
+        scanner, start, buffer = @keeps.pop
         if buffer
+          # trace(__method__, :rescan, start, buffer)
           string = @scanner.string
-          keep = string.byteslice(start, string.bytesize - start)
+          if scanner == @scanner
+            keep = string.byteslice(start, string.bytesize - start)
+          else
+            keep = string
+          end
           if keep and not keep.empty?
             @inputs.unshift(StringIO.new(keep))
             @last_scanner = false
           end
           @scanner = StringScanner.new(buffer)
         else
+          if @scanner != scanner
+            message = "scanners are different but no buffer: "
+            message += "#{@scanner.inspect}(#{@scanner.object_id}): "
+            message += "#{scanner.inspect}(#{scanner.object_id})"
+            raise UnexpectedError, message
+          end
+          # trace(__method__, :repos, start, buffer)
           @scanner.pos = start
         end
         read_chunk if @scanner.eos?
       end
 
       def keep_drop
-        @keeps.pop
+        _, _, buffer = @keeps.pop
+        # trace(__method__, :done, :empty) unless buffer
+        return unless buffer
+
+        last_keep = @keeps.last
+        # trace(__method__, :done, :no_last_keep) unless last_keep
+        return unless last_keep
+
+        if last_keep[2]
+          last_keep[2] << buffer
+        else
+          last_keep[2] = buffer
+        end
+        # trace(__method__, :done)
       end
 
       def rest
         @scanner.rest
       end
 
+      def check(pattern)
+        @scanner.check(pattern)
+      end
+
       private
-      def read_chunk
-        return false if @last_scanner
+      def trace(*args)
+        pp([*args, @scanner, @scanner&.string, @scanner&.pos, @keeps])
+      end
 
-        unless @keeps.empty?
-          keep = @keeps.last
-          keep_start = keep[0]
-          string = @scanner.string
-          keep_data = string.byteslice(keep_start, @scanner.pos - keep_start)
-          if keep_data
-            keep_buffer = keep[1]
-            if keep_buffer
-              keep_buffer << keep_data
-            else
-              keep[1] = keep_data.dup
-            end
+      def adjust_last_keep
+        # trace(__method__, :start)
+
+        keep = @keeps.last
+        # trace(__method__, :done, :empty) if keep.nil?
+        return if keep.nil?
+
+        scanner, start, buffer = keep
+        string = @scanner.string
+        if @scanner != scanner
+          start = 0
+        end
+        if start == 0 and @scanner.eos?
+          keep_data = string
+        else
+          keep_data = string.byteslice(start, @scanner.pos - start)
+        end
+        if keep_data
+          if buffer
+            buffer << keep_data
+          else
+            keep[2] = keep_data.dup
           end
-          keep[0] = 0
         end
 
+        # trace(__method__, :done)
+      end
+
+      def read_chunk
+        return false if @last_scanner
+
+        adjust_last_keep
+
         input = @inputs.first
         case input
         when StringIO
           string = input.read
           raise InvalidEncoding unless string.valid_encoding?
+          # trace(__method__, :stringio, string)
           @scanner = StringScanner.new(string)
           @inputs.shift
           @last_scanner = @inputs.empty?
@@ -237,6 +299,7 @@ class CSV
           chunk = input.gets(@row_separator, @chunk_size)
           if chunk
             raise InvalidEncoding unless chunk.valid_encoding?
+            # trace(__method__, :chunk, chunk)
             @scanner = StringScanner.new(chunk)
             if input.respond_to?(:eof?) and input.eof?
               @inputs.shift
@@ -244,6 +307,7 @@ class CSV
             end
             true
           else
+            # trace(__method__, :no_chunk)
             @scanner = StringScanner.new("".encode(@encoding))
             @inputs.shift
             @last_scanner = @inputs.empty?
@@ -278,7 +342,11 @@ class CSV
     end
 
     def field_size_limit
-      @field_size_limit
+      @max_field_size&.succ
+    end
+
+    def max_field_size
+      @max_field_size
     end
 
     def skip_lines
@@ -346,6 +414,16 @@ class CSV
         end
         message = "Invalid byte sequence in #{@encoding}"
         raise MalformedCSVError.new(message, lineno)
+      rescue UnexpectedError => error
+        if @scanner
+          ignore_broken_line
+          lineno = @lineno
+        else
+          lineno = @lineno + 1
+        end
+        message = "This should not be happen: #{error.message}: "
+        message += "Please report this to https://github.com/ruby/csv/issues"
+        raise MalformedCSVError.new(message, lineno)
       end
     end
 
@@ -390,7 +468,7 @@ class CSV
         @backslash_quote = false
       end
       @unconverted_fields = @options[:unconverted_fields]
-      @field_size_limit = @options[:field_size_limit]
+      @max_field_size = @options[:max_field_size]
       @skip_blanks = @options[:skip_blanks]
       @fields_converter = @options[:fields_converter]
       @header_fields_converter = @options[:header_fields_converter]
@@ -680,9 +758,10 @@ class CSV
       case headers
       when Array
         @raw_headers = headers
+        quoted_fields = [false] * @raw_headers.size
         @use_headers = true
       when String
-        @raw_headers = parse_headers(headers)
+        @raw_headers, quoted_fields = parse_headers(headers)
         @use_headers = true
       when nil, false
         @raw_headers = nil
@@ -692,21 +771,28 @@ class CSV
         @use_headers = true
       end
       if @raw_headers
-        @headers = adjust_headers(@raw_headers)
+        @headers = adjust_headers(@raw_headers, quoted_fields)
       else
         @headers = nil
       end
     end
 
     def parse_headers(row)
-      CSV.parse_line(row,
-                     col_sep:    @column_separator,
-                     row_sep:    @row_separator,
-                     quote_char: @quote_character)
+      quoted_fields = []
+      converter = lambda do |field, info|
+        quoted_fields << info.quoted?
+        field
+      end
+      headers = CSV.parse_line(row,
+                               col_sep:    @column_separator,
+                               row_sep:    @row_separator,
+                               quote_char: @quote_character,
+                               converters: [converter])
+      [headers, quoted_fields]
     end
 
-    def adjust_headers(headers)
-      adjusted_headers = @header_fields_converter.convert(headers, nil, @lineno)
+    def adjust_headers(headers, quoted_fields)
+      adjusted_headers = @header_fields_converter.convert(headers, nil, @lineno, quoted_fields)
       adjusted_headers.each {|h| h.freeze if h.is_a? String}
       adjusted_headers
     end
@@ -729,28 +815,28 @@ class CSV
       sample[0, 128].index(@quote_character)
     end
 
-    SCANNER_TEST = (ENV["CSV_PARSER_SCANNER_TEST"] == "yes")
-    if SCANNER_TEST
-      class UnoptimizedStringIO
-        def initialize(string)
-          @io = StringIO.new(string, "rb:#{string.encoding}")
-        end
+    class UnoptimizedStringIO # :nodoc:
+      def initialize(string)
+        @io = StringIO.new(string, "rb:#{string.encoding}")
+      end
 
-        def gets(*args)
-          @io.gets(*args)
-        end
+      def gets(*args)
+        @io.gets(*args)
+      end
 
-        def each_line(*args, &block)
-          @io.each_line(*args, &block)
-        end
+      def each_line(*args, &block)
+        @io.each_line(*args, &block)
+      end
 
-        def eof?
-          @io.eof?
-        end
+      def eof?
+        @io.eof?
       end
+    end
 
-      SCANNER_TEST_CHUNK_SIZE =
-        Integer((ENV["CSV_PARSER_SCANNER_TEST_CHUNK_SIZE"] || "1"), 10)
+    SCANNER_TEST = (ENV["CSV_PARSER_SCANNER_TEST"] == "yes")
+    if SCANNER_TEST
+      SCANNER_TEST_CHUNK_SIZE_NAME = "CSV_PARSER_SCANNER_TEST_CHUNK_SIZE"
+      SCANNER_TEST_CHUNK_SIZE_VALUE = ENV[SCANNER_TEST_CHUNK_SIZE_NAME]
       def build_scanner
         inputs = @samples.collect do |sample|
           UnoptimizedStringIO.new(sample)
@@ -760,10 +846,17 @@ class CSV
         else
           inputs << @input
         end
+        begin
+          chunk_size_value = ENV[SCANNER_TEST_CHUNK_SIZE_NAME]
+        rescue # Ractor::IsolationError
+          # Ractor on Ruby 3.0 can't read ENV value.
+          chunk_size_value = SCANNER_TEST_CHUNK_SIZE_VALUE
+        end
+        chunk_size = Integer((chunk_size_value || "1"), 10)
         InputsScanner.new(inputs,
                           @encoding,
                           @row_separator,
-                          chunk_size: SCANNER_TEST_CHUNK_SIZE)
+                          chunk_size: chunk_size)
       end
     else
       def build_scanner
@@ -826,6 +919,14 @@ class CSV
       end
     end
 
+    def validate_field_size(field)
+      return unless @max_field_size
+      return if field.size <= @max_field_size
+      ignore_broken_line
+      message = "Field size exceeded: #{field.size} > #{@max_field_size}"
+      raise MalformedCSVError.new(message, @lineno)
+    end
+
     def parse_no_quote(&block)
       @scanner.each_line(@row_separator) do |line|
         next if @skip_lines and skip_line?(line)
@@ -835,9 +936,16 @@ class CSV
         if line.empty?
           next if @skip_blanks
           row = []
+          quoted_fields = []
         else
           line = strip_value(line)
           row = line.split(@split_column_separator, -1)
+          quoted_fields = [false] * row.size
+          if @max_field_size
+            row.each do |column|
+              validate_field_size(column)
+            end
+          end
           n_columns = row.size
           i = 0
           while i < n_columns
@@ -846,7 +954,7 @@ class CSV
           end
         end
         @last_line = original_line
-        emit_row(row, &block)
+        emit_row(row, quoted_fields, &block)
       end
     end
 
@@ -868,31 +976,37 @@ class CSV
             next
           end
           row = []
+          quoted_fields = []
         elsif line.include?(@cr) or line.include?(@lf)
           @scanner.keep_back
           @need_robust_parsing = true
           return parse_quotable_robust(&block)
         else
           row = line.split(@split_column_separator, -1)
+          quoted_fields = []
           n_columns = row.size
           i = 0
           while i < n_columns
             column = row[i]
             if column.empty?
+              quoted_fields << false
               row[i] = nil
             else
               n_quotes = column.count(@quote_character)
               if n_quotes.zero?
+                quoted_fields << false
                 # no quote
               elsif n_quotes == 2 and
                    column.start_with?(@quote_character) and
                    column.end_with?(@quote_character)
+                quoted_fields << true
                 row[i] = column[1..-2]
               else
                 @scanner.keep_back
                 @need_robust_parsing = true
                 return parse_quotable_robust(&block)
               end
+              validate_field_size(row[i])
             end
             i += 1
           end
@@ -900,13 +1014,14 @@ class CSV
         @scanner.keep_drop
         @scanner.keep_start
         @last_line = original_line
-        emit_row(row, &block)
+        emit_row(row, quoted_fields, &block)
       end
       @scanner.keep_drop
     end
 
     def parse_quotable_robust(&block)
       row = []
+      quoted_fields = []
       skip_needless_lines
       start_row
       while true
@@ -916,32 +1031,39 @@ class CSV
         value = parse_column_value
         if value
           @scanner.scan_all(@strip_value) if @strip_value
-          if @field_size_limit and value.size >= @field_size_limit
-            ignore_broken_line
-            raise MalformedCSVError.new("Field size exceeded", @lineno)
-          end
+          validate_field_size(value)
         end
         if parse_column_end
           row << value
+          quoted_fields << @quoted_column_value
         elsif parse_row_end
           if row.empty? and value.nil?
-            emit_row([], &block) unless @skip_blanks
+            emit_row([], [], &block) unless @skip_blanks
           else
             row << value
-            emit_row(row, &block)
+            quoted_fields << @quoted_column_value
+            emit_row(row, quoted_fields, &block)
             row = []
+            quoted_fields = []
           end
           skip_needless_lines
           start_row
         elsif @scanner.eos?
           break if row.empty? and value.nil?
           row << value
-          emit_row(row, &block)
+          quoted_fields << @quoted_column_value
+          emit_row(row, quoted_fields, &block)
           break
         else
           if @quoted_column_value
+            if liberal_parsing? and (new_line = @scanner.check(@line_end))
+              message =
+                "Illegal end-of-line sequence outside of a quoted field " +
+                "<#{new_line.inspect}>"
+            else
+              message = "Any value after quoted field isn't allowed"
+            end
             ignore_broken_line
-            message = "Any value after quoted field isn't allowed"
             raise MalformedCSVError.new(message, @lineno)
           elsif @unquoted_column_value and
                 (new_line = @scanner.scan(@line_end))
@@ -1034,7 +1156,7 @@ class CSV
       if (n_quotes % 2).zero?
         quotes[0, (n_quotes - 2) / 2]
       else
-        value = quotes[0, (n_quotes - 1) / 2]
+        value = quotes[0, n_quotes / 2]
         while true
           quoted_value = @scanner.scan_all(@quoted_value)
           value << quoted_value if quoted_value
@@ -1058,11 +1180,9 @@ class CSV
           n_quotes = quotes.size
           if n_quotes == 1
             break
-          elsif (n_quotes % 2) == 1
-            value << quotes[0, (n_quotes - 1) / 2]
-            break
           else
             value << quotes[0, n_quotes / 2]
+            break if (n_quotes % 2) == 1
           end
         end
         value
@@ -1098,18 +1218,15 @@ class CSV
 
     def strip_value(value)
       return value unless @strip
-      return nil if value.nil?
+      return value if value.nil?
 
       case @strip
       when String
-        size = value.size
-        while value.start_with?(@strip)
-          size -= 1
-          value = value[1, size]
+        while value.delete_prefix!(@strip)
+          # do nothing
         end
-        while value.end_with?(@strip)
-          size -= 1
-          value = value[0, size]
+        while value.delete_suffix!(@strip)
+          # do nothing
         end
       else
         value.strip!
@@ -1132,22 +1249,22 @@ class CSV
       @scanner.keep_start
     end
 
-    def emit_row(row, &block)
+    def emit_row(row, quoted_fields, &block)
       @lineno += 1
 
       raw_row = row
       if @use_headers
         if @headers.nil?
-          @headers = adjust_headers(row)
+          @headers = adjust_headers(row, quoted_fields)
           return unless @return_headers
           row = Row.new(@headers, row, true)
         else
           row = Row.new(@headers,
-                        @fields_converter.convert(raw_row, @headers, @lineno))
+                        @fields_converter.convert(raw_row, @headers, @lineno, quoted_fields))
         end
       else
         # convert fields, if needed...
-        row = @fields_converter.convert(raw_row, nil, @lineno)
+        row = @fields_converter.convert(raw_row, nil, @lineno, quoted_fields)
       end
 
       # inject unconverted fields and accessor, if requested...
diff --git a/lib/csv/row.rb b/lib/csv/row.rb
index 0f465ea2a3..86323f7d0a 100644
--- a/lib/csv/row.rb
+++ b/lib/csv/row.rb
@@ -3,30 +3,105 @@
 require "forwardable"
 
 class CSV
+  # = \CSV::Row
+  # A \CSV::Row instance represents a \CSV table row.
+  # (see {class CSV}[../CSV.html]).
   #
-  # A CSV::Row is part Array and part Hash. It retains an order for the fields
-  # and allows duplicates just as an Array would, but also allows you to access
-  # fields by name just as you could if they were in a Hash.
+  # The instance may have:
+  # - Fields: each is an object, not necessarily a \String.
+  # - Headers: each serves a key, and also need not be a \String.
   #
-  # All rows returned by CSV will be constructed from this class, if header row
-  # processing is activated.
+  # === Instance Methods
+  #
+  # \CSV::Row has three groups of instance methods:
+  # - Its own internally defined instance methods.
+  # - Methods included by module Enumerable.
+  # - Methods delegated to class Array.:
+  #   * Array#empty?
+  #   * Array#length
+  #   * Array#size
+  #
+  # == Creating a \CSV::Row Instance
+  #
+  # Commonly, a new \CSV::Row instance is created by parsing \CSV source
+  # that has headers:
+  #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+  #   table = CSV.parse(source, headers: true)
+  #   table.each {|row| p row }
+  # Output:
+  #   #<CSV::Row "Name":"foo" "Value":"0">
+  #   #<CSV::Row "Name":"bar" "Value":"1">
+  #   #<CSV::Row "Name":"baz" "Value":"2">
+  #
+  # You can also create a row directly. See ::new.
+  #
+  # == Headers
+  #
+  # Like a \CSV::Table, a \CSV::Row has headers.
+  #
+  # A \CSV::Row that was created by parsing \CSV source
+  # inherits its headers from the table:
+  #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+  #   table = CSV.parse(source, headers: true)
+  #   row = table.first
+  #   row.headers # => ["Name", "Value"]
+  #
+  # You can also create a new row with headers;
+  # like the keys in a \Hash, the headers need not be Strings:
+  #   row = CSV::Row.new([:name, :value], ['foo', 0])
+  #   row.headers # => [:name, :value]
+  #
+  # The new row retains its headers even if added to a table
+  # that has headers:
+  #   table << row # => #<CSV::Table mode:col_or_row row_count:5>
+  #   row.headers # => [:name, :value]
+  #   row[:name] # => "foo"
+  #   row['Name'] # => nil
+  #
+  #
+  #
+  # == Accessing Fields
+  #
+  # You may access a field in a \CSV::Row with either its \Integer index
+  # (\Array-style) or its header (\Hash-style).
+  #
+  # Fetch a field using method #[]:
+  #   row = CSV::Row.new(['Name', 'Value'], ['foo', 0])
+  #   row[1] # => 0
+  #   row['Value'] # => 0
+  #
+  # Set a field using method #[]=:
+  #   row = CSV::Row.new(['Name', 'Value'], ['foo', 0])
+  #   row # => #<CSV::Row "Name":"foo" "Value":0>
+  #   row[0] = 'bar'
+  #   row['Value'] = 1
+  #   row # => #<CSV::Row "Name":"bar" "Value":1>
   #
   class Row
-    #
-    # Constructs a new CSV::Row from +headers+ and +fields+, which are expected
-    # to be Arrays. If one Array is shorter than the other, it will be padded
-    # with +nil+ objects.
-    #
-    # The optional +header_row+ parameter can be set to +true+ to indicate, via
-    # CSV::Row.header_row?() and CSV::Row.field_row?(), that this is a header
-    # row. Otherwise, the row assumes to be a field row.
-    #
-    # A CSV::Row object supports the following Array methods through delegation:
-    #
-    # * empty?()
-    # * length()
-    # * size()
-    #
+    # :call-seq:
+    #   CSV::Row.new(headers, fields, header_row = false) -> csv_row
+    #
+    # Returns the new \CSV::Row instance constructed from
+    # arguments +headers+ and +fields+; both should be Arrays;
+    # note that the fields need not be Strings:
+    #   row = CSV::Row.new(['Name', 'Value'], ['foo', 0])
+    #   row # => #<CSV::Row "Name":"foo" "Value":0>
+    #
+    # If the \Array lengths are different, the shorter is +nil+-filled:
+    #   row = CSV::Row.new(['Name', 'Value', 'Date', 'Size'], ['foo', 0])
+    #   row # => #<CSV::Row "Name":"foo" "Value":0 "Date":nil "Size":nil>
+    #
+    # Each \CSV::Row object is either a <i>field row</i> or a <i>header row</i>;
+    # by default, a new row is a field row;  for the row created above:
+    #   row.field_row? # => true
+    #   row.header_row? # => false
+    #
+    # If the optional argument +header_row+ is given as +true+,
+    # the created row is a header row:
+    #   row = CSV::Row.new(['Name', 'Value'], ['foo', 0], header_row = true)
+    #   row # => #<CSV::Row "Name":"foo" "Value":0>
+    #   row.field_row? # => false
+    #   row.header_row? # => true
     def initialize(headers, fields, header_row = false)
       @header_row = header_row
       headers.each { |h| h.freeze if h.is_a? String }
@@ -48,6 +123,10 @@ class CSV
     extend Forwardable
     def_delegators :@row, :empty?, :length, :size
 
+    # :call-seq:
+    #   row.initialize_copy(other_row) -> self
+    #
+    # Calls superclass method.
     def initialize_copy(other)
       super_return_value = super
       @row = @row.collect(&:dup)
@@ -71,7 +150,7 @@ class CSV
     end
 
     # :call-seq:
-    #    row.headers
+    #    row.headers -> array_of_headers
     #
     # Returns the headers for this row:
     #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
@@ -83,9 +162,9 @@ class CSV
     end
 
     # :call-seq:
-    #   field(index)
-    #   field(header)
-    #   field(header, offset)
+    #   field(index) -> value
+    #   field(header) -> value
+    #   field(header, offset) -> value
     #
     # Returns the field value for the given +index+ or +header+.
     #
@@ -137,9 +216,9 @@ class CSV
 
     #
     # :call-seq:
-    #   fetch(header)
-    #   fetch(header, default)
-    #   fetch(header) {|row| ... }
+    #   fetch(header) -> value
+    #   fetch(header, default) -> value
+    #   fetch(header) {|row| ... } -> value
     #
     # Returns the field value as specified by +header+.
     #
@@ -193,7 +272,7 @@ class CSV
     end
 
     # :call-seq:
-    #   row.has_key?(header)
+    #   row.has_key?(header) -> true or false
     #
     # Returns +true+ if there is a field with the given +header+,
     # +false+ otherwise.
@@ -320,7 +399,7 @@ class CSV
     end
 
     # :call-seq:
-    #   row.push(*values) ->self
+    #   row.push(*values) -> self
     #
     # Appends each of the given +values+ to +self+ as a field; returns +self+:
     #   source = "Name,Name,Name\nFoo,Bar,Baz\n"
@@ -403,7 +482,7 @@ class CSV
     end
 
     # :call-seq:
-    #   self.fields(*specifiers)
+    #   self.fields(*specifiers) -> array_of_fields
     #
     # Returns field values per the given +specifiers+, which may be any mixture of:
     # - \Integer index.
@@ -471,15 +550,26 @@ class CSV
     end
     alias_method :values_at, :fields
 
-    #
     # :call-seq:
-    #   index( header )
-    #   index( header, offset )
+    #   index(header) -> index
+    #   index(header, offset) -> index
     #
-    # This method will return the index of a field with the provided +header+.
-    # The +offset+ can be used to locate duplicate header names, as described in
-    # CSV::Row.field().
+    # Returns the index for the given header, if it exists;
+    # otherwise returns +nil+.
     #
+    # With the single argument +header+, returns the index
+    # of the first-found field with the given +header+:
+    #   source = "Name,Name,Name\nFoo,Bar,Baz\n"
+    #   table = CSV.parse(source, headers: true)
+    #   row = table[0]
+    #   row.index('Name') # => 0
+    #   row.index('NAME') # => nil
+    #
+    # With arguments +header+ and +offset+,
+    # returns the index of the first-found field with given +header+,
+    # but ignoring the first +offset+ fields:
+    #   row.index('Name', 1) # => 1
+    #   row.index('Name', 3) # => nil
     def index(header, minimum_index = 0)
       # find the pair
       index = headers[minimum_index..-1].index(header)
@@ -487,24 +577,36 @@ class CSV
       index.nil? ? nil : index + minimum_index
     end
 
+    # :call-seq:
+    #   row.field?(value) -> true or false
     #
-    # Returns +true+ if +data+ matches a field in this row, and +false+
-    # otherwise.
-    #
+    # Returns +true+ if +value+ is a field in this row, +false+ otherwise:
+    #   source = "Name,Name,Name\nFoo,Bar,Baz\n"
+    #   table = CSV.parse(source, headers: true)
+    #   row = table[0]
+    #   row.field?('Bar') # => true
+    #   row.field?('BAR') # => false
     def field?(data)
       fields.include? data
     end
 
     include Enumerable
 
+    # :call-seq:
+    #   row.each {|header, value| ... } -> self
     #
-    # Yields each pair of the row as header and field tuples (much like
-    # iterating over a Hash). This method returns the row for chaining.
-    #
-    # If no block is given, an Enumerator is returned.
-    #
-    # Support for Enumerable.
+    # Calls the block with each header-value pair; returns +self+:
+    #   source = "Name,Name,Name\nFoo,Bar,Baz\n"
+    #   table = CSV.parse(source, headers: true)
+    #   row = table[0]
+    #   row.each {|header, value| p [header, value] }
+    # Output:
+    #   ["Name", "Foo"]
+    #   ["Name", "Bar"]
+    #   ["Name", "Baz"]
     #
+    # If no block is given, returns a new Enumerator:
+    #   row.each # => #<Enumerator: #<CSV::Row "Name":"Foo" "Name":"Bar" "Name":"Baz">:each>
     def each(&block)
       return enum_for(__method__) { size } unless block_given?
 
@@ -515,10 +617,19 @@ class CSV
 
     alias_method :each_pair, :each
 
+    # :call-seq:
+    #   row == other -> true or false
     #
-    # Returns +true+ if this row contains the same headers and fields in the
-    # same order as +other+.
-    #
+    # Returns +true+ if +other+ is a /CSV::Row that has the same
+    # fields (headers and values) in the same order as +self+;
+    # otherwise returns +false+:
+    #   source = "Name,Name,Name\nFoo,Bar,Baz\n"
+    #   table = CSV.parse(source, headers: true)
+    #   row = table[0]
+    #   other_row = table[0]
+    #   row == other_row # => true
+    #   other_row = table[1]
+    #   row == other_row # => false
     def ==(other)
       return @row == other.row if other.is_a? CSV::Row
       @row == other
@@ -548,9 +659,31 @@ class CSV
     end
     alias_method :to_hash, :to_h
 
+    # :call-seq:
+    #   row.deconstruct_keys(keys) -> hash
+    #
+    # Returns the new \Hash suitable for pattern matching containing only the
+    # keys specified as an argument.
+    def deconstruct_keys(keys)
+      if keys.nil?
+        to_h
+      else
+        keys.to_h { |key| [key, self[key]] }
+      end
+    end
+
     alias_method :to_ary, :to_a
 
     # :call-seq:
+    #   row.deconstruct -> array
+    #
+    # Returns the new \Array suitable for pattern matching containing the values
+    # of the row.
+    def deconstruct
+      fields
+    end
+
+    # :call-seq:
     #   row.to_csv -> csv_string
     #
     # Returns the row as a \CSV String. Headers are not included:
@@ -570,7 +703,7 @@ class CSV
     # by +index_or_header+ and +specifiers+.
     #
     # The nested objects may be instances of various classes.
-    # See {Dig Methods}[https://docs.ruby-lang.org/en/master/doc/dig_methods_rdoc.html].
+    # See {Dig Methods}[rdoc-ref:dig_methods.rdoc].
     #
     # Examples:
     #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
diff --git a/lib/csv/table.rb b/lib/csv/table.rb
index 1ce0dd6daf..fb19f5453f 100644
--- a/lib/csv/table.rb
+++ b/lib/csv/table.rb
@@ -3,31 +3,199 @@
 require "forwardable"
 
 class CSV
+  # = \CSV::Table
+  # A \CSV::Table instance represents \CSV data.
+  # (see {class CSV}[../CSV.html]).
   #
-  # A CSV::Table is a two-dimensional data structure for representing CSV
-  # documents. Tables allow you to work with the data by row or column,
-  # manipulate the data, and even convert the results back to CSV, if needed.
+  # The instance may have:
+  # - Rows: each is a Table::Row object.
+  # - Headers: names for the columns.
   #
-  # All tables returned by CSV will be constructed from this class, if header
-  # row processing is activated.
+  # === Instance Methods
   #
+  # \CSV::Table has three groups of instance methods:
+  # - Its own internally defined instance methods.
+  # - Methods included by module Enumerable.
+  # - Methods delegated to class Array.:
+  #   * Array#empty?
+  #   * Array#length
+  #   * Array#size
+  #
+  # == Creating a \CSV::Table Instance
+  #
+  # Commonly, a new \CSV::Table instance is created by parsing \CSV source
+  # using headers:
+  #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+  #   table = CSV.parse(source, headers: true)
+  #   table.class # => CSV::Table
+  #
+  # You can also create an instance directly. See ::new.
+  #
+  # == Headers
+  #
+  # If a table has headers, the headers serve as labels for the columns of data.
+  # Each header serves as the label for its column.
+  #
+  # The headers for a \CSV::Table object are stored as an \Array of Strings.
+  #
+  # Commonly, headers are defined in the first row of \CSV source:
+  #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+  #   table = CSV.parse(source, headers: true)
+  #   table.headers # => ["Name", "Value"]
+  #
+  # If no headers are defined, the \Array is empty:
+  #   table = CSV::Table.new([])
+  #   table.headers # => []
+  #
+  # == Access Modes
+  #
+  # \CSV::Table provides three modes for accessing table data:
+  # - \Row mode.
+  # - Column mode.
+  # - Mixed mode (the default for a new table).
+  #
+  # The access mode for a\CSV::Table instance affects the behavior
+  # of some of its instance methods:
+  # - #[]
+  # - #[]=
+  # - #delete
+  # - #delete_if
+  # - #each
+  # - #values_at
+  #
+  # === \Row Mode
+  #
+  # Set a table to row mode with method #by_row!:
+  #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+  #   table = CSV.parse(source, headers: true)
+  #   table.by_row! # => #<CSV::Table mode:row row_count:4>
+  #
+  # Specify a single row by an \Integer index:
+  #   # Get a row.
+  #   table[1] # => #<CSV::Row "Name":"bar" "Value":"1">
+  #   # Set a row, then get it.
+  #   table[1] = CSV::Row.new(['Name', 'Value'], ['bam', 3])
+  #   table[1] # => #<CSV::Row "Name":"bam" "Value":3>
+  #
+  # Specify a sequence of rows by a \Range:
+  #   # Get rows.
+  #   table[1..2] # => [#<CSV::Row "Name":"bam" "Value":3>, #<CSV::Row "Name":"baz" "Value":"2">]
+  #   # Set rows, then get them.
+  #   table[1..2] = [
+  #     CSV::Row.new(['Name', 'Value'], ['bat', 4]),
+  #     CSV::Row.new(['Name', 'Value'], ['bad', 5]),
+  #   ]
+  #   table[1..2] # => [["Name", #<CSV::Row "Name":"bat" "Value":4>], ["Value", #<CSV::Row "Name":"bad" "Value":5>]]
+  #
+  # === Column Mode
+  #
+  # Set a table to column mode with method #by_col!:
+  #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+  #   table = CSV.parse(source, headers: true)
+  #   table.by_col! # => #<CSV::Table mode:col row_count:4>
+  #
+  # Specify a column by an \Integer index:
+  #   # Get a column.
+  #   table[0]
+  #   # Set a column, then get it.
+  #   table[0] = ['FOO', 'BAR', 'BAZ']
+  #   table[0] # => ["FOO", "BAR", "BAZ"]
+  #
+  # Specify a column by its \String header:
+  #   # Get a column.
+  #   table['Name'] # => ["FOO", "BAR", "BAZ"]
+  #   # Set a column, then get it.
+  #   table['Name'] = ['Foo', 'Bar', 'Baz']
+  #   table['Name'] # => ["Foo", "Bar", "Baz"]
+  #
+  # === Mixed Mode
+  #
+  # In mixed mode, you can refer to either rows or columns:
+  # - An \Integer index refers to a row.
+  # - A \Range index refers to multiple rows.
+  # - A \String index refers to a column.
+  #
+  # Set a table to mixed mode with method #by_col_or_row!:
+  #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+  #   table = CSV.parse(source, headers: true)
+  #   table.by_col_or_row! # => #<CSV::Table mode:col_or_row row_count:4>
+  #
+  # Specify a single row by an \Integer index:
+  #   # Get a row.
+  #   table[1] # => #<CSV::Row "Name":"bar" "Value":"1">
+  #   # Set a row, then get it.
+  #   table[1] = CSV::Row.new(['Name', 'Value'], ['bam', 3])
+  #   table[1] # => #<CSV::Row "Name":"bam" "Value":3>
+  #
+  # Specify a sequence of rows by a \Range:
+  #   # Get rows.
+  #   table[1..2] # => [#<CSV::Row "Name":"bam" "Value":3>, #<CSV::Row "Name":"baz" "Value":"2">]
+  #   # Set rows, then get them.
+  #   table[1] = CSV::Row.new(['Name', 'Value'], ['bat', 4])
+  #   table[2] = CSV::Row.new(['Name', 'Value'], ['bad', 5])
+  #   table[1..2] # => [["Name", #<CSV::Row "Name":"bat" "Value":4>], ["Value", #<CSV::Row "Name":"bad" "Value":5>]]
+  #
+  # Specify a column by its \String header:
+  #   # Get a column.
+  #   table['Name'] # => ["foo", "bat", "bad"]
+  #   # Set a column, then get it.
+  #   table['Name'] = ['Foo', 'Bar', 'Baz']
+  #   table['Name'] # => ["Foo", "Bar", "Baz"]
   class Table
+    # :call-seq:
+    #   CSV::Table.new(array_of_rows, headers = nil) -> csv_table
+    #
+    # Returns a new \CSV::Table object.
+    #
+    # - Argument +array_of_rows+ must be an \Array of CSV::Row objects.
+    # - Argument +headers+, if given, may be an \Array of Strings.
+    #
+    # ---
+    #
+    # Create an empty \CSV::Table object:
+    #   table = CSV::Table.new([])
+    #   table # => #<CSV::Table mode:col_or_row row_count:1>
+    #
+    # Create a non-empty \CSV::Table object:
+    #   rows = [
+    #     CSV::Row.new([], []),
+    #     CSV::Row.new([], []),
+    #     CSV::Row.new([], []),
+    #   ]
+    #   table  = CSV::Table.new(rows)
+    #   table # => #<CSV::Table mode:col_or_row row_count:4>
+    #
+    # ---
     #
-    # Constructs a new CSV::Table from +array_of_rows+, which are expected
-    # to be CSV::Row objects. All rows are assumed to have the same headers.
+    # If argument +headers+ is an \Array of Strings,
+    # those Strings become the table's headers:
+    #   table = CSV::Table.new([], headers: ['Name', 'Age'])
+    #   table.headers # => ["Name", "Age"]
     #
-    # The optional +headers+ parameter can be set to Array of headers.
-    # If headers aren't set, headers are fetched from CSV::Row objects.
-    # Otherwise, headers() method will return headers being set in
-    # headers argument.
+    # If argument +headers+ is not given and the table has rows,
+    # the headers are taken from the first row:
+    #   rows = [
+    #     CSV::Row.new(['Foo', 'Bar'], []),
+    #     CSV::Row.new(['foo', 'bar'], []),
+    #     CSV::Row.new(['FOO', 'BAR'], []),
+    #   ]
+    #   table  = CSV::Table.new(rows)
+    #   table.headers # => ["Foo", "Bar"]
     #
-    # A CSV::Table object supports the following Array methods through
-    # delegation:
+    # If argument +headers+ is not given and the table is empty (has no rows),
+    # the headers are also empty:
+    #   table  = CSV::Table.new([])
+    #   table.headers # => []
     #
-    # * empty?()
-    # * length()
-    # * size()
+    # ---
     #
+    # Raises an exception if argument +array_of_rows+ is not an \Array object:
+    #   # Raises NoMethodError (undefined method `first' for :foo:Symbol):
+    #   CSV::Table.new(:foo)
+    #
+    # Raises an exception if an element of +array_of_rows+ is not a \CSV::Table object:
+    #   # Raises NoMethodError (undefined method `headers' for :foo:Symbol):
+    #   CSV::Table.new([:foo])
     def initialize(array_of_rows, headers: nil)
       @table = array_of_rows
       @headers = headers
@@ -54,88 +222,141 @@ class CSV
     extend Forwardable
     def_delegators :@table, :empty?, :length, :size
 
+    # :call-seq:
+    #   table.by_col -> table_dup
     #
-    # Returns a duplicate table object, in column mode. This is handy for
-    # chaining in a single call without changing the table mode, but be aware
-    # that this method can consume a fair amount of memory for bigger data sets.
+    # Returns a duplicate of +self+, in column mode
+    # (see {Column Mode}[#class-CSV::Table-label-Column+Mode]):
+    #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+    #   table = CSV.parse(source, headers: true)
+    #   table.mode # => :col_or_row
+    #   dup_table = table.by_col
+    #   dup_table.mode # => :col
+    #   dup_table.equal?(table) # => false # It's a dup
     #
-    # This method returns the duplicate table for chaining. Don't chain
-    # destructive methods (like []=()) this way though, since you are working
-    # with a duplicate.
+    # This may be used to chain method calls without changing the mode
+    # (but also will affect performance and memory usage):
+    #   dup_table.by_col['Name']
     #
+    # Also note that changes to the duplicate table will not affect the original.
     def by_col
       self.class.new(@table.dup).by_col!
     end
 
+    # :call-seq:
+    #   table.by_col! -> self
     #
-    # Switches the mode of this table to column mode. All calls to indexing and
-    # iteration methods will work with columns until the mode is changed again.
-    #
-    # This method returns the table and is safe to chain.
-    #
+    # Sets the mode for +self+ to column mode
+    # (see {Column Mode}[#class-CSV::Table-label-Column+Mode]); returns +self+:
+    #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+    #   table = CSV.parse(source, headers: true)
+    #   table.mode # => :col_or_row
+    #   table1 = table.by_col!
+    #   table.mode # => :col
+    #   table1.equal?(table) # => true # Returned self
     def by_col!
       @mode = :col
 
       self
     end
 
+    # :call-seq:
+    #   table.by_col_or_row -> table_dup
     #
-    # Returns a duplicate table object, in mixed mode. This is handy for
-    # chaining in a single call without changing the table mode, but be aware
-    # that this method can consume a fair amount of memory for bigger data sets.
+    # Returns a duplicate of +self+, in mixed mode
+    # (see {Mixed Mode}[#class-CSV::Table-label-Mixed+Mode]):
+    #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+    #   table = CSV.parse(source, headers: true).by_col!
+    #   table.mode # => :col
+    #   dup_table = table.by_col_or_row
+    #   dup_table.mode # => :col_or_row
+    #   dup_table.equal?(table) # => false # It's a dup
     #
-    # This method returns the duplicate table for chaining.  Don't chain
-    # destructive methods (like []=()) this way though, since you are working
-    # with a duplicate.
+    # This may be used to chain method calls without changing the mode
+    # (but also will affect performance and memory usage):
+    #   dup_table.by_col_or_row['Name']
     #
+    # Also note that changes to the duplicate table will not affect the original.
     def by_col_or_row
       self.class.new(@table.dup).by_col_or_row!
     end
 
+    # :call-seq:
+    #   table.by_col_or_row! -> self
     #
-    # Switches the mode of this table to mixed mode. All calls to indexing and
-    # iteration methods will use the default intelligent indexing system until
-    # the mode is changed again. In mixed mode an index is assumed to be a row
-    # reference while anything else is assumed to be column access by headers.
-    #
-    # This method returns the table and is safe to chain.
-    #
+    # Sets the mode for +self+ to mixed mode
+    # (see {Mixed Mode}[#class-CSV::Table-label-Mixed+Mode]); returns +self+:
+    #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+    #   table = CSV.parse(source, headers: true).by_col!
+    #   table.mode # => :col
+    #   table1 = table.by_col_or_row!
+    #   table.mode # => :col_or_row
+    #   table1.equal?(table) # => true # Returned self
     def by_col_or_row!
       @mode = :col_or_row
 
       self
     end
 
+    # :call-seq:
+    #   table.by_row -> table_dup
     #
-    # Returns a duplicate table object, in row mode.  This is handy for chaining
-    # in a single call without changing the table mode, but be aware that this
-    # method can consume a fair amount of memory for bigger data sets.
+    # Returns a duplicate of +self+, in row mode
+    # (see {Row Mode}[#class-CSV::Table-label-Row+Mode]):
+    #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+    #   table = CSV.parse(source, headers: true)
+    #   table.mode # => :col_or_row
+    #   dup_table = table.by_row
+    #   dup_table.mode # => :row
+    #   dup_table.equal?(table) # => false # It's a dup
     #
-    # This method returns the duplicate table for chaining.  Don't chain
-    # destructive methods (like []=()) this way though, since you are working
-    # with a duplicate.
+    # This may be used to chain method calls without changing the mode
+    # (but also will affect performance and memory usage):
+    #   dup_table.by_row[1]
     #
+    # Also note that changes to the duplicate table will not affect the original.
     def by_row
       self.class.new(@table.dup).by_row!
     end
 
+    # :call-seq:
+    #   table.by_row! -> self
     #
-    # Switches the mode of this table to row mode. All calls to indexing and
-    # iteration methods will work with rows until the mode is changed again.
-    #
-    # This method returns the table and is safe to chain.
-    #
+    # Sets the mode for +self+ to row mode
+    # (see {Row Mode}[#class-CSV::Table-label-Row+Mode]); returns +self+:
+    #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+    #   table = CSV.parse(source, headers: true)
+    #   table.mode # => :col_or_row
+    #   table1 = table.by_row!
+    #   table.mode # => :row
+    #   table1.equal?(table) # => true # Returned self
     def by_row!
       @mode = :row
 
       self
     end
 
+    # :call-seq:
+    #   table.headers -> array_of_headers
     #
-    # Returns the headers for the first row of this table (assumed to match all
-    # other rows). The headers Array passed to CSV::Table.new is returned for
-    # empty tables.
+    # Returns a new \Array containing the \String headers for the table.
     #
+    # If the table is not empty, returns the headers from the first row:
+    #   rows = [
+    #     CSV::Row.new(['Foo', 'Bar'], []),
+    #     CSV::Row.new(['FOO', 'BAR'], []),
+    #     CSV::Row.new(['foo', 'bar'], []),
+    #   ]
+    #   table  = CSV::Table.new(rows)
+    #   table.headers # => ["Foo", "Bar"]
+    #   table.delete(0)
+    #   table.headers # => ["FOO", "BAR"]
+    #   table.delete(0)
+    #   table.headers # => ["foo", "bar"]
+    #
+    # If the table is empty, returns a copy of the headers in the table itself:
+    #   table.delete(0)
+    #   table.headers # => ["Foo", "Bar"]
     def headers
       if @table.empty?
         @headers.dup
@@ -145,17 +366,21 @@ class CSV
     end
 
     # :call-seq:
-    #   table[n] -> row
-    #   table[range] -> array_of_rows
-    #   table[header] -> array_of_fields
+    #   table[n] -> row or column_data
+    #   table[range] -> array_of_rows or array_of_column_data
+    #   table[header] -> array_of_column_data
     #
     # Returns data from the table;  does not modify the table.
     #
     # ---
     #
-    # The expression <tt>table[n]</tt>, where +n+ is a non-negative \Integer,
-    # returns the +n+th row of the table, if that row exists,
-    # and if the access mode is <tt>:row</tt> or <tt>:col_or_row</tt>:
+    # Fetch a \Row by Its \Integer Index::
+    # - Form: <tt>table[n]</tt>, +n+ an integer.
+    # - Access mode: <tt>:row</tt> or <tt>:col_or_row</tt>.
+    # - Return value: _nth_ row of the table, if that row exists;
+    #   otherwise +nil+.
+    #
+    # Returns the _nth_ row of the table if that row exists:
     #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
     #   table = CSV.parse(source, headers: true)
     #   table.by_row! # => #<CSV::Table mode:row row_count:4>
@@ -168,20 +393,45 @@ class CSV
     #
     # Returns +nil+ if +n+ is too large or too small:
     #   table[4] # => nil
-    #   table[-4] => nil
+    #   table[-4] # => nil
     #
     # Raises an exception if the access mode is <tt>:row</tt>
-    # and +n+ is not an
-    # {Integer-convertible object}[https://docs.ruby-lang.org/en/master/implicit_conversion_rdoc.html#label-Integer-Convertible+Objects].
+    # and +n+ is not an \Integer:
     #   table.by_row! # => #<CSV::Table mode:row row_count:4>
     #   # Raises TypeError (no implicit conversion of String into Integer):
     #   table['Name']
     #
     # ---
     #
-    # The expression <tt>table[range]</tt>, where +range+ is a Range object,
-    # returns rows from the table, beginning at row <tt>range.first</tt>,
-    # if those rows exist, and if the access mode is <tt>:row</tt> or <tt>:col_or_row</tt>:
+    # Fetch a Column by Its \Integer Index::
+    # - Form: <tt>table[n]</tt>, +n+ an \Integer.
+    # - Access mode: <tt>:col</tt>.
+    # - Return value: _nth_ column of the table, if that column exists;
+    #   otherwise an \Array of +nil+ fields of length <tt>self.size</tt>.
+    #
+    # Returns the _nth_ column of the table if that column exists:
+    #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+    #   table = CSV.parse(source, headers: true)
+    #   table.by_col! # => #<CSV::Table mode:col row_count:4>
+    #   table[1] # => ["0", "1", "2"]
+    #
+    # Counts backward from the last column if +n+ is negative:
+    #   table[-2] # => ["foo", "bar", "baz"]
+    #
+    # Returns an \Array of +nil+ fields if +n+ is too large or too small:
+    #   table[4] # => [nil, nil, nil]
+    #   table[-4] # => [nil, nil, nil]
+    #
+    # ---
+    #
+    # Fetch Rows by \Range::
+    # - Form: <tt>table[range]</tt>, +range+ a \Range object.
+    # - Access mode: <tt>:row</tt> or <tt>:col_or_row</tt>.
+    # - Return value: rows from the table, beginning at row <tt>range.start</tt>,
+    #   if those rows exists.
+    #
+    # Returns rows from the table, beginning at row <tt>range.first</tt>,
+    # if those rows exist:
     #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
     #   table = CSV.parse(source, headers: true)
     #   table.by_row! # => #<CSV::Table mode:row row_count:4>
@@ -191,11 +441,11 @@ class CSV
     #   rows = table[1..2] # => #<CSV::Row "Name":"bar" "Value":"1">
     #   rows # => [#<CSV::Row "Name":"bar" "Value":"1">, #<CSV::Row "Name":"baz" "Value":"2">]
     #
-    # If there are too few rows, returns all from <tt>range.first</tt> to the end:
+    # If there are too few rows, returns all from <tt>range.start</tt> to the end:
     #   rows = table[1..50] # => #<CSV::Row "Name":"bar" "Value":"1">
     #   rows # => [#<CSV::Row "Name":"bar" "Value":"1">, #<CSV::Row "Name":"baz" "Value":"2">]
     #
-    # Special case:  if <tt>range.start == table.size</tt>, returns an empty \Array:
+    # Special case: if <tt>range.start == table.size</tt>, returns an empty \Array:
     #   table[table.size..50] # => []
     #
     # If <tt>range.end</tt> is negative, calculates the ending index from the end:
@@ -211,9 +461,41 @@ class CSV
     #
     # ---
     #
-    # The expression <tt>table[header]</tt>, where +header+ is a \String,
-    # returns column values (\Array of \Strings) if the column exists
-    # and if the access mode is <tt>:col</tt> or <tt>:col_or_row</tt>:
+    # Fetch Columns by \Range::
+    # - Form: <tt>table[range]</tt>, +range+ a \Range object.
+    # - Access mode: <tt>:col</tt>.
+    # - Return value: column data from the table, beginning at column <tt>range.start</tt>,
+    #   if those columns exist.
+    #
+    # Returns column values from the table, if the column exists;
+    # the values are arranged by row:
+    #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+    #   table = CSV.parse(source, headers: true)
+    #   table.by_col!
+    #   table[0..1] # => [["foo", "0"], ["bar", "1"], ["baz", "2"]]
+    #
+    # Special case: if <tt>range.start == headers.size</tt>,
+    # returns an \Array (size: <tt>table.size</tt>) of empty \Arrays:
+    #   table[table.headers.size..50] # => [[], [], []]
+    #
+    # If <tt>range.end</tt> is negative, calculates the ending index from the end:
+    #   table[0..-1] # => [["foo", "0"], ["bar", "1"], ["baz", "2"]]
+    #
+    # If <tt>range.start</tt> is negative, calculates the starting index from the end:
+    #   table[-2..2] # => [["foo", "0"], ["bar", "1"], ["baz", "2"]]
+    #
+    # If <tt>range.start</tt> is larger than <tt>table.size</tt>,
+    # returns an \Array of +nil+ values:
+    #   table[4..4] # => [nil, nil, nil]
+    #
+    # ---
+    #
+    # Fetch a Column by Its \String Header::
+    # - Form: <tt>table[header]</tt>, +header+ a \String header.
+    # - Access mode: <tt>:col</tt> or <tt>:col_or_row</tt>
+    # - Return value: column data from the table, if that +header+ exists.
+    #
+    # Returns column values from the table, if the column exists:
     #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
     #   table = CSV.parse(source, headers: true)
     #   table.by_col! # => #<CSV::Table mode:col row_count:4>
@@ -238,22 +520,132 @@ class CSV
       end
     end
 
+    # :call-seq:
+    #   table[n] = row -> row
+    #   table[n] = field_or_array_of_fields -> field_or_array_of_fields
+    #   table[header] = field_or_array_of_fields -> field_or_array_of_fields
     #
-    # In the default mixed mode, this method assigns rows for index access and
-    # columns for header access. You can force the index association by first
-    # calling by_col!() or by_row!().
+    # Puts data onto the table.
     #
-    # Rows may be set to an Array of values (which will inherit the table's
-    # headers()) or a CSV::Row.
+    # ---
+    #
+    # Set a \Row by Its \Integer Index::
+    # - Form: <tt>table[n] = row</tt>, +n+ an \Integer,
+    #   +row+ a \CSV::Row instance or an \Array of fields.
+    # - Access mode: <tt>:row</tt> or <tt>:col_or_row</tt>.
+    # - Return value: +row+.
+    #
+    # If the row exists, it is replaced:
+    #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+    #   table = CSV.parse(source, headers: true)
+    #   new_row = CSV::Row.new(['Name', 'Value'], ['bat', 3])
+    #   table.by_row! # => #<CSV::Table mode:row row_count:4>
+    #   return_value = table[0] = new_row
+    #   return_value.equal?(new_row) # => true # Returned the row
+    #   table[0].to_h # => {"Name"=>"bat", "Value"=>3}
+    #
+    # With access mode <tt>:col_or_row</tt>:
+    #   table.by_col_or_row! # => #<CSV::Table mode:col_or_row row_count:4>
+    #   table[0] = CSV::Row.new(['Name', 'Value'], ['bam', 4])
+    #   table[0].to_h # => {"Name"=>"bam", "Value"=>4}
+    #
+    # With an \Array instead of a \CSV::Row, inherits headers from the table:
+    #   array = ['bad', 5]
+    #   return_value = table[0] = array
+    #   return_value.equal?(array) # => true # Returned the array
+    #   table[0].to_h # => {"Name"=>"bad", "Value"=>5}
     #
-    # Columns may be set to a single value, which is copied to each row of the
-    # column, or an Array of values. Arrays of values are assigned to rows top
-    # to bottom in row major order. Excess values are ignored and if the Array
-    # does not have a value for each row the extra rows will receive a +nil+.
+    # If the row does not exist, extends the table by adding rows:
+    # assigns rows with +nil+ as needed:
+    #   table.size # => 3
+    #   table[5] = ['bag', 6]
+    #   table.size # => 6
+    #   table[3] # => nil
+    #   table[4]# => nil
+    #   table[5].to_h # => {"Name"=>"bag", "Value"=>6}
+    #
+    # Note that the +nil+ rows are actually +nil+, not a row of +nil+ fields.
     #
-    # Assigning to an existing column or row clobbers the data. Assigning to
-    # new columns creates them at the right end of the table.
+    # ---
     #
+    # Set a Column by Its \Integer Index::
+    # - Form: <tt>table[n] = array_of_fields</tt>, +n+ an \Integer,
+    #   +array_of_fields+ an \Array of \String fields.
+    # - Access mode: <tt>:col</tt>.
+    # - Return value: +array_of_fields+.
+    #
+    # If the column exists, it is replaced:
+    #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+    #   table = CSV.parse(source, headers: true)
+    #   new_col = [3, 4, 5]
+    #   table.by_col! # => #<CSV::Table mode:col row_count:4>
+    #   return_value = table[1] = new_col
+    #   return_value.equal?(new_col) # => true # Returned the column
+    #   table[1] # => [3, 4, 5]
+    #   # The rows, as revised:
+    #   table.by_row! # => #<CSV::Table mode:row row_count:4>
+    #   table[0].to_h # => {"Name"=>"foo", "Value"=>3}
+    #   table[1].to_h # => {"Name"=>"bar", "Value"=>4}
+    #   table[2].to_h # => {"Name"=>"baz", "Value"=>5}
+    #   table.by_col! # => #<CSV::Table mode:col row_count:4>
+    #
+    # If there are too few values, fills with +nil+ values:
+    #   table[1] = [0]
+    #   table[1] # => [0, nil, nil]
+    #
+    # If there are too many values, ignores the extra values:
+    #   table[1] = [0, 1, 2, 3, 4]
+    #   table[1] # => [0, 1, 2]
+    #
+    # If a single value is given, replaces all fields in the column with that value:
+    #   table[1] = 'bat'
+    #   table[1] # => ["bat", "bat", "bat"]
+    #
+    # ---
+    #
+    # Set a Column by Its \String Header::
+    # - Form: <tt>table[header] = field_or_array_of_fields</tt>,
+    #   +header+ a \String header, +field_or_array_of_fields+ a field value
+    #   or an \Array of \String fields.
+    # - Access mode: <tt>:col</tt> or <tt>:col_or_row</tt>.
+    # - Return value: +field_or_array_of_fields+.
+    #
+    # If the column exists, it is replaced:
+    #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+    #   table = CSV.parse(source, headers: true)
+    #   new_col = [3, 4, 5]
+    #   table.by_col! # => #<CSV::Table mode:col row_count:4>
+    #   return_value = table['Value'] = new_col
+    #   return_value.equal?(new_col) # => true # Returned the column
+    #   table['Value'] # => [3, 4, 5]
+    #   # The rows, as revised:
+    #   table.by_row! # => #<CSV::Table mode:row row_count:4>
+    #   table[0].to_h # => {"Name"=>"foo", "Value"=>3}
+    #   table[1].to_h # => {"Name"=>"bar", "Value"=>4}
+    #   table[2].to_h # => {"Name"=>"baz", "Value"=>5}
+    #   table.by_col! # => #<CSV::Table mode:col row_count:4>
+    #
+    # If there are too few values, fills with +nil+ values:
+    #   table['Value'] = [0]
+    #   table['Value'] # => [0, nil, nil]
+    #
+    # If there are too many values, ignores the extra values:
+    #   table['Value'] = [0, 1, 2, 3, 4]
+    #   table['Value'] # => [0, 1, 2]
+    #
+    # If the column does not exist, extends the table by adding columns:
+    #   table['Note'] = ['x', 'y', 'z']
+    #   table['Note'] # => ["x", "y", "z"]
+    #   # The rows, as revised:
+    #   table.by_row!
+    #   table[0].to_h # => {"Name"=>"foo", "Value"=>0, "Note"=>"x"}
+    #   table[1].to_h # => {"Name"=>"bar", "Value"=>1, "Note"=>"y"}
+    #   table[2].to_h # => {"Name"=>"baz", "Value"=>2, "Note"=>"z"}
+    #   table.by_col!
+    #
+    # If a single value is given, replaces all fields in the column with that value:
+    #   table['Value'] = 'bat'
+    #   table['Value'] # => ["bat", "bat", "bat"]
     def []=(index_or_header, value)
       if @mode == :row or  # by index
          (@mode == :col_or_row and index_or_header.is_a? Integer)
@@ -463,6 +855,9 @@ class CSV
       end
     end
 
+    # :call-seq:
+    #   table.delete_if {|row_or_column| ... } -> self
+    #
     # Removes rows or columns for which the block returns a truthy value;
     # returns +self+.
     #
@@ -495,9 +890,8 @@ class CSV
       if @mode == :row or @mode == :col_or_row  # by index
         @table.delete_if(&block)
       else                                      # by header
-        deleted = []
         headers.each do |header|
-          deleted << delete(header) if yield([header, self[header]])
+          delete(header) if yield([header, self[header]])
         end
       end
 
@@ -506,6 +900,9 @@ class CSV
 
     include Enumerable
 
+    # :call-seq:
+    #  table.each {|row_or_column| ... ) -> self
+    #
     # Calls the block with each row or column; returns +self+.
     #
     # When the access mode is <tt>:row</tt> or <tt>:col_or_row</tt>,
@@ -534,7 +931,9 @@ class CSV
       return enum_for(__method__) { @mode == :col ? headers.size : size } unless block_given?
 
       if @mode == :col
-        headers.each { |header| yield([header, self[header]]) }
+        headers.each.with_index do |header, i|
+          yield([header, @table.map {|row| row[header, i]}])
+        end
       else
         @table.each(&block)
       end
@@ -542,6 +941,9 @@ class CSV
       self # for chaining
     end
 
+    # :call-seq:
+    #   table == other_table -> true or false
+    #
     # Returns +true+ if all each row of +self+ <tt>==</tt>
     # the corresponding row of +other_table+, otherwise, +false+.
     #
@@ -565,10 +967,14 @@ class CSV
       @table == other
     end
 
+    # :call-seq:
+    #   table.to_a -> array_of_arrays
     #
-    # Returns the table as an Array of Arrays. Headers will be the first row,
-    # then all of the field rows will follow.
-    #
+    # Returns the table as an \Array of \Arrays;
+    # the headers are in the first row:
+    #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+    #   table = CSV.parse(source, headers: true)
+    #   table.to_a # => [["Name", "Value"], ["foo", "0"], ["bar", "1"], ["baz", "2"]]
     def to_a
       array = [headers]
       @table.each do |row|
@@ -578,16 +984,29 @@ class CSV
       array
     end
 
+    # :call-seq:
+    #   table.to_csv(**options) -> csv_string
     #
-    # Returns the table as a complete CSV String. Headers will be listed first,
-    # then all of the field rows.
+    # Returns the table as \CSV string.
+    # See {Options for Generating}[../CSV.html#class-CSV-label-Options+for+Generating].
     #
-    # This method assumes you want the Table.headers(), unless you explicitly
-    # pass <tt>:write_headers => false</tt>.
+    # Defaults option +write_headers+ to +true+:
+    #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+    #   table = CSV.parse(source, headers: true)
+    #   table.to_csv # => "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
     #
-    def to_csv(write_headers: true, **options)
+    # Omits the headers if option +write_headers+ is given as +false+
+    # (see {Option +write_headers+}[../CSV.html#class-CSV-label-Option+write_headers]):
+    #   table.to_csv(write_headers: false) # => "foo,0\nbar,1\nbaz,2\n"
+    #
+    # Limit rows if option +limit+ is given like +2+:
+    #   table.to_csv(limit: 2) # => "Name,Value\nfoo,0\nbar,1\n"
+    def to_csv(write_headers: true, limit: nil, **options)
       array = write_headers ? [headers.to_csv(**options)] : []
-      @table.each do |row|
+      limit ||= @table.size
+      limit = @table.size + 1 + limit if limit < 0
+      limit = 0 if limit < 0
+      @table.first(limit).each do |row|
         array.push(row.fields.to_csv(**options)) unless row.header_row?
       end
 
@@ -613,9 +1032,24 @@ class CSV
       end
     end
 
-    # Shows the mode and size of this table in a US-ASCII String.
+    # :call-seq:
+    #   table.inspect => string
+    #
+    # Returns a <tt>US-ASCII</tt>-encoded \String showing table:
+    # - Class: <tt>CSV::Table</tt>.
+    # - Access mode: <tt>:row</tt>, <tt>:col</tt>, or <tt>:col_or_row</tt>.
+    # - Size:  Row count, including the header row.
+    #
+    # Example:
+    #   source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n"
+    #   table = CSV.parse(source, headers: true)
+    #   table.inspect # => "#<CSV::Table mode:col_or_row row_count:4>\nName,Value\nfoo,0\nbar,1\nbaz,2\n"
+    #
     def inspect
-      "#<#{self.class} mode:#{@mode} row_count:#{to_a.size}>".encode("US-ASCII")
+      inspected = +"#<#{self.class} mode:#{@mode} row_count:#{to_a.size}>"
+      summary = to_csv(limit: 5)
+      inspected << "\n" << summary if summary.encoding.ascii_compatible?
+      inspected
     end
   end
 end
diff --git a/lib/csv/version.rb b/lib/csv/version.rb
index d1d0dc0e02..e05d63d801 100644
--- a/lib/csv/version.rb
+++ b/lib/csv/version.rb
@@ -2,5 +2,5 @@
 
 class CSV
   # The version of the installed library.
-  VERSION = "3.2.2"
+  VERSION = "3.2.6"
 end
diff --git a/lib/csv/writer.rb b/lib/csv/writer.rb
index 4a9a35c5af..030a295bc9 100644
--- a/lib/csv/writer.rb
+++ b/lib/csv/writer.rb
@@ -1,11 +1,8 @@
 # frozen_string_literal: true
 
 require_relative "input_record_separator"
-require_relative "match_p"
 require_relative "row"
 
-using CSV::MatchP if CSV.const_defined?(:MatchP)
-
 class CSV
   # Note: Don't use this class directly. This is an internal class.
   class Writer
@@ -42,7 +39,10 @@ class CSV
       @headers ||= row if @use_headers
       @lineno += 1
 
-      row = @fields_converter.convert(row, nil, lineno) if @fields_converter
+      if @fields_converter
+        quoted_fields = [false] * row.size
+        row = @fields_converter.convert(row, nil, lineno, quoted_fields)
+      end
 
       i = -1
       converted_row = row.collect do |field|
@@ -97,7 +97,7 @@ class CSV
       return unless @headers
 
       converter = @options[:header_fields_converter]
-      @headers = converter.convert(@headers, nil, 0)
+      @headers = converter.convert(@headers, nil, 0, [])
       @headers.each do |header|
         header.freeze if header.is_a?(String)
       end
diff --git a/lib/delegate.rb b/lib/delegate.rb
index 70d4e4ad1d..387a5f063d 100644
--- a/lib/delegate.rb
+++ b/lib/delegate.rb
@@ -39,7 +39,7 @@
 # Be advised, RDoc will not detect delegated methods.
 #
 class Delegator < BasicObject
-  VERSION = "0.2.0"
+  VERSION = "0.3.0"
 
   kernel = ::Kernel.dup
   kernel.class_eval do
diff --git a/lib/did_you_mean/core_ext/name_error.rb b/lib/did_you_mean/core_ext/name_error.rb
index eb3ef117a0..8c170c4b90 100644
--- a/lib/did_you_mean/core_ext/name_error.rb
+++ b/lib/did_you_mean/core_ext/name_error.rb
@@ -1,24 +1,49 @@
 module DidYouMean
   module Correctable
-    SKIP_TO_S_FOR_SUPER_LOOKUP = true
-    private_constant :SKIP_TO_S_FOR_SUPER_LOOKUP
+    if Exception.method_defined?(:detailed_message)
+      # just for compatibility
+      def original_message
+        # we cannot use alias here because
+        to_s
+      end
+
+      def detailed_message(highlight: true, did_you_mean: true, **)
+        msg = super.dup
+
+        return msg unless did_you_mean
+
+        suggestion = DidYouMean.formatter.message_for(corrections)
+
+        if highlight
+          suggestion = suggestion.gsub(/.+/) { "\e[1m" + $& + "\e[m" }
+        end
 
-    def original_message
-      meth = method(:to_s)
-      while meth.owner.const_defined?(:SKIP_TO_S_FOR_SUPER_LOOKUP)
-        meth = meth.super_method
+        msg << suggestion
+        msg
+      rescue
+        super
+      end
+    else
+      SKIP_TO_S_FOR_SUPER_LOOKUP = true
+      private_constant :SKIP_TO_S_FOR_SUPER_LOOKUP
+
+      def original_message
+        meth = method(:to_s)
+        while meth.owner.const_defined?(:SKIP_TO_S_FOR_SUPER_LOOKUP)
+          meth = meth.super_method
+        end
+        meth.call
       end
-      meth.call
-    end
 
-    def to_s
-      msg = super.dup
-      suggestion = DidYouMean.formatter.message_for(corrections)
+      def to_s
+        msg = super.dup
+        suggestion = DidYouMean.formatter.message_for(corrections)
 
-      msg << suggestion if !msg.include?(suggestion)
-      msg
-    rescue
-      super
+        msg << suggestion if !msg.include?(suggestion)
+        msg
+      rescue
+        super
+      end
     end
 
     def corrections
diff --git a/lib/did_you_mean/formatters/verbose_formatter.rb b/lib/did_you_mean/formatters/verbose_formatter.rb
index 8ee98fa070..f6623681f2 100644
--- a/lib/did_you_mean/formatters/verbose_formatter.rb
+++ b/lib/did_you_mean/formatters/verbose_formatter.rb
@@ -1,8 +1,9 @@
+# frozen-string-literal: true
+
 warn "`require 'did_you_mean/formatters/verbose_formatter'` is deprecated and falls back to the default formatter. "
 
 require_relative '../formatter'
 
-# frozen-string-literal: true
 module DidYouMean
   # For compatibility:
   VerboseFormatter = Formatter
diff --git a/lib/did_you_mean/spell_checkers/method_name_checker.rb b/lib/did_you_mean/spell_checkers/method_name_checker.rb
index d8ebaa4616..b5cbbb5da6 100644
--- a/lib/did_you_mean/spell_checkers/method_name_checker.rb
+++ b/lib/did_you_mean/spell_checkers/method_name_checker.rb
@@ -59,6 +59,13 @@ module DidYouMean
         method_names = receiver.methods + receiver.singleton_methods
         method_names += receiver.private_methods if @private_call
         method_names.uniq!
+        # Assume that people trying to use a writer are not interested in a reader
+        # and vice versa
+        if method_name.match?(/=\Z/)
+          method_names.select! { |name| name.match?(/=\Z/) }
+        else
+          method_names.reject! { |name| name.match?(/=\Z/) }
+        end
         method_names
       else
         []
diff --git a/lib/did_you_mean/spell_checkers/name_error_checkers/variable_name_checker.rb b/lib/did_you_mean/spell_checkers/name_error_checkers/variable_name_checker.rb
index 36d00349c6..9a6e04fe64 100644
--- a/lib/did_you_mean/spell_checkers/name_error_checkers/variable_name_checker.rb
+++ b/lib/did_you_mean/spell_checkers/name_error_checkers/variable_name_checker.rb
@@ -79,7 +79,7 @@ module DidYouMean
     def corrections
       @corrections ||= SpellChecker
                      .new(dictionary: (RB_RESERVED_WORDS + lvar_names + method_names + ivar_names + cvar_names))
-                     .correct(name) - NAMES_TO_EXCLUDE[@name]
+                     .correct(name).uniq - NAMES_TO_EXCLUDE[@name]
     end
   end
 end
diff --git a/lib/did_you_mean/version.rb b/lib/did_you_mean/version.rb
index b5fe50b5ed..5745ca1efd 100644
--- a/lib/did_you_mean/version.rb
+++ b/lib/did_you_mean/version.rb
@@ -1,3 +1,3 @@
 module DidYouMean
-  VERSION = "1.6.1".freeze
+  VERSION = "1.6.3".freeze
 end
diff --git a/lib/drb/version.rb b/lib/drb/version.rb
index efaccf0319..10d33445b6 100644
--- a/lib/drb/version.rb
+++ b/lib/drb/version.rb
@@ -1,3 +1,3 @@
 module DRb
-  VERSION = "2.1.0"
+  VERSION = "2.1.1"
 end
diff --git a/lib/erb.gemspec b/lib/erb.gemspec
index 43ffc89c69..d973cc10de 100644
--- a/lib/erb.gemspec
+++ b/lib/erb.gemspec
@@ -8,8 +8,8 @@ end
 Gem::Specification.new do |spec|
   spec.name          = 'erb'
   spec.version       = ERB.const_get(:VERSION, false)
-  spec.authors       = ['Masatoshi SEKI']
-  spec.email         = ['seki@ruby-lang.org']
+  spec.authors       = ['Masatoshi SEKI', 'Takashi Kokubun']
+  spec.email         = ['seki@ruby-lang.org', 'takashikkbn@gmail.com']
 
   spec.summary       = %q{An easy to use but powerful templating system for Ruby.}
   spec.description   = %q{An easy to use but powerful templating system for Ruby.}
@@ -27,5 +27,12 @@ Gem::Specification.new do |spec|
   spec.executables   = ['erb']
   spec.require_paths = ['lib']
 
-  spec.add_dependency 'cgi'
+  if RUBY_ENGINE == 'jruby'
+    spec.platform = 'java'
+  else
+    spec.required_ruby_version = '>= 2.7.0'
+    spec.extensions = ['ext/erb/escape/extconf.rb']
+  end
+
+  spec.add_dependency 'cgi', '>= 0.3.3'
 end
diff --git a/lib/erb.rb b/lib/erb.rb
index 0e42425a60..754419f819 100644
--- a/lib/erb.rb
+++ b/lib/erb.rb
@@ -14,6 +14,9 @@
 
 require 'cgi/util'
 require 'erb/version'
+require 'erb/compiler'
+require 'erb/def_method'
+require 'erb/util'
 
 #
 # = ERB -- Ruby Templating
@@ -264,486 +267,7 @@ class ERB
   def self.version
     VERSION
   end
-end
 
-#--
-# ERB::Compiler
-class ERB
-  # = ERB::Compiler
-  #
-  # Compiles ERB templates into Ruby code; the compiled code produces the
-  # template result when evaluated. ERB::Compiler provides hooks to define how
-  # generated output is handled.
-  #
-  # Internally ERB does something like this to generate the code returned by
-  # ERB#src:
-  #
-  #   compiler = ERB::Compiler.new('<>')
-  #   compiler.pre_cmd    = ["_erbout=+''"]
-  #   compiler.put_cmd    = "_erbout.<<"
-  #   compiler.insert_cmd = "_erbout.<<"
-  #   compiler.post_cmd   = ["_erbout"]
-  #
-  #   code, enc = compiler.compile("Got <%= obj %>!\n")
-  #   puts code
-  #
-  # <i>Generates</i>:
-  #
-  #   #coding:UTF-8
-  #   _erbout=+''; _erbout.<< "Got ".freeze; _erbout.<<(( obj ).to_s); _erbout.<< "!\n".freeze; _erbout
-  #
-  # By default the output is sent to the print method.  For example:
-  #
-  #   compiler = ERB::Compiler.new('<>')
-  #   code, enc = compiler.compile("Got <%= obj %>!\n")
-  #   puts code
-  #
-  # <i>Generates</i>:
-  #
-  #   #coding:UTF-8
-  #   print "Got ".freeze; print(( obj ).to_s); print "!\n".freeze
-  #
-  # == Evaluation
-  #
-  # The compiled code can be used in any context where the names in the code
-  # correctly resolve. Using the last example, each of these print 'Got It!'
-  #
-  # Evaluate using a variable:
-  #
-  #   obj = 'It'
-  #   eval code
-  #
-  # Evaluate using an input:
-  #
-  #   mod = Module.new
-  #   mod.module_eval %{
-  #     def get(obj)
-  #       #{code}
-  #     end
-  #   }
-  #   extend mod
-  #   get('It')
-  #
-  # Evaluate using an accessor:
-  #
-  #   klass = Class.new Object
-  #   klass.class_eval %{
-  #     attr_accessor :obj
-  #     def initialize(obj)
-  #       @obj = obj
-  #     end
-  #     def get_it
-  #       #{code}
-  #     end
-  #   }
-  #   klass.new('It').get_it
-  #
-  # Good! See also ERB#def_method, ERB#def_module, and ERB#def_class.
-  class Compiler # :nodoc:
-    class PercentLine # :nodoc:
-      def initialize(str)
-        @value = str
-      end
-      attr_reader :value
-      alias :to_s :value
-    end
-
-    class Scanner # :nodoc:
-      @scanner_map = {}
-      class << self
-        def register_scanner(klass, trim_mode, percent)
-          @scanner_map[[trim_mode, percent]] = klass
-        end
-        alias :regist_scanner :register_scanner
-      end
-
-      def self.default_scanner=(klass)
-        @default_scanner = klass
-      end
-
-      def self.make_scanner(src, trim_mode, percent)
-        klass = @scanner_map.fetch([trim_mode, percent], @default_scanner)
-        klass.new(src, trim_mode, percent)
-      end
-
-      DEFAULT_STAGS = %w(<%% <%= <%# <%).freeze
-      DEFAULT_ETAGS = %w(%%> %>).freeze
-      def initialize(src, trim_mode, percent)
-        @src = src
-        @stag = nil
-        @stags = DEFAULT_STAGS
-        @etags = DEFAULT_ETAGS
-      end
-      attr_accessor :stag
-      attr_reader :stags, :etags
-
-      def scan; end
-    end
-
-    class TrimScanner < Scanner # :nodoc:
-      def initialize(src, trim_mode, percent)
-        super
-        @trim_mode = trim_mode
-        @percent = percent
-        if @trim_mode == '>'
-          @scan_reg  = /(.*?)(%>\r?\n|#{(stags + etags).join('|')}|\n|\z)/m
-          @scan_line = self.method(:trim_line1)
-        elsif @trim_mode == '<>'
-          @scan_reg  = /(.*?)(%>\r?\n|#{(stags + etags).join('|')}|\n|\z)/m
-          @scan_line = self.method(:trim_line2)
-        elsif @trim_mode == '-'
-          @scan_reg  = /(.*?)(^[ \t]*<%\-|<%\-|-%>\r?\n|-%>|#{(stags + etags).join('|')}|\z)/m
-          @scan_line = self.method(:explicit_trim_line)
-        else
-          @scan_reg  = /(.*?)(#{(stags + etags).join('|')}|\n|\z)/m
-          @scan_line = self.method(:scan_line)
-        end
-      end
-
-      def scan(&block)
-        @stag = nil
-        if @percent
-          @src.each_line do |line|
-            percent_line(line, &block)
-          end
-        else
-          @scan_line.call(@src, &block)
-        end
-        nil
-      end
-
-      def percent_line(line, &block)
-        if @stag || line[0] != ?%
-          return @scan_line.call(line, &block)
-        end
-
-        line[0] = ''
-        if line[0] == ?%
-          @scan_line.call(line, &block)
-        else
-          yield(PercentLine.new(line.chomp))
-        end
-      end
-
-      def scan_line(line)
-        line.scan(@scan_reg) do |tokens|
-          tokens.each do |token|
-            next if token.empty?
-            yield(token)
-          end
-        end
-      end
-
-      def trim_line1(line)
-        line.scan(@scan_reg) do |tokens|
-          tokens.each do |token|
-            next if token.empty?
-            if token == "%>\n" || token == "%>\r\n"
-              yield('%>')
-              yield(:cr)
-            else
-              yield(token)
-            end
-          end
-        end
-      end
-
-      def trim_line2(line)
-        head = nil
-        line.scan(@scan_reg) do |tokens|
-          tokens.each do |token|
-            next if token.empty?
-            head = token unless head
-            if token == "%>\n" || token == "%>\r\n"
-              yield('%>')
-              if is_erb_stag?(head)
-                yield(:cr)
-              else
-                yield("\n")
-              end
-              head = nil
-            else
-              yield(token)
-              head = nil if token == "\n"
-            end
-          end
-        end
-      end
-
-      def explicit_trim_line(line)
-        line.scan(@scan_reg) do |tokens|
-          tokens.each do |token|
-            next if token.empty?
-            if @stag.nil? && /[ \t]*<%-/ =~ token
-              yield('<%')
-            elsif @stag && (token == "-%>\n" || token == "-%>\r\n")
-              yield('%>')
-              yield(:cr)
-            elsif @stag && token == '-%>'
-              yield('%>')
-            else
-              yield(token)
-            end
-          end
-        end
-      end
-
-      ERB_STAG = %w(<%= <%# <%)
-      def is_erb_stag?(s)
-        ERB_STAG.member?(s)
-      end
-    end
-
-    Scanner.default_scanner = TrimScanner
-
-    begin
-      require 'strscan'
-    rescue LoadError
-    else
-      class SimpleScanner < Scanner # :nodoc:
-        def scan
-          stag_reg = (stags == DEFAULT_STAGS) ? /(.*?)(<%[%=#]?|\z)/m : /(.*?)(#{stags.join('|')}|\z)/m
-          etag_reg = (etags == DEFAULT_ETAGS) ? /(.*?)(%%?>|\z)/m : /(.*?)(#{etags.join('|')}|\z)/m
-          scanner = StringScanner.new(@src)
-          while ! scanner.eos?
-            scanner.scan(@stag ? etag_reg : stag_reg)
-            yield(scanner[1])
-            yield(scanner[2])
-          end
-        end
-      end
-      Scanner.register_scanner(SimpleScanner, nil, false)
-
-      class ExplicitScanner < Scanner # :nodoc:
-        def scan
-          stag_reg = /(.*?)(^[ \t]*<%-|<%-|#{stags.join('|')}|\z)/m
-          etag_reg = /(.*?)(-%>|#{etags.join('|')}|\z)/m
-          scanner = StringScanner.new(@src)
-          while ! scanner.eos?
-            scanner.scan(@stag ? etag_reg : stag_reg)
-            yield(scanner[1])
-
-            elem = scanner[2]
-            if /[ \t]*<%-/ =~ elem
-              yield('<%')
-            elsif elem == '-%>'
-              yield('%>')
-              yield(:cr) if scanner.scan(/(\r?\n|\z)/)
-            else
-              yield(elem)
-            end
-          end
-        end
-      end
-      Scanner.register_scanner(ExplicitScanner, '-', false)
-    end
-
-    class Buffer # :nodoc:
-      def initialize(compiler, enc=nil, frozen=nil)
-        @compiler = compiler
-        @line = []
-        @script = +''
-        @script << "#coding:#{enc}\n" if enc
-        @script << "#frozen-string-literal:#{frozen}\n" unless frozen.nil?
-        @compiler.pre_cmd.each do |x|
-          push(x)
-        end
-      end
-      attr_reader :script
-
-      def push(cmd)
-        @line << cmd
-      end
-
-      def cr
-        @script << (@line.join('; '))
-        @line = []
-        @script << "\n"
-      end
-
-      def close
-        return unless @line
-        @compiler.post_cmd.each do |x|
-          push(x)
-        end
-        @script << (@line.join('; '))
-        @line = nil
-      end
-    end
-
-    def add_put_cmd(out, content)
-      out.push("#{@put_cmd} #{content.dump}.freeze#{"\n" * content.count("\n")}")
-    end
-
-    def add_insert_cmd(out, content)
-      out.push("#{@insert_cmd}((#{content}).to_s)")
-    end
-
-    # Compiles an ERB template into Ruby code.  Returns an array of the code
-    # and encoding like ["code", Encoding].
-    def compile(s)
-      enc = s.encoding
-      raise ArgumentError, "#{enc} is not ASCII compatible" if enc.dummy?
-      s = s.b # see String#b
-      magic_comment = detect_magic_comment(s, enc)
-      out = Buffer.new(self, *magic_comment)
-
-      self.content = +''
-      scanner = make_scanner(s)
-      scanner.scan do |token|
-        next if token.nil?
-        next if token == ''
-        if scanner.stag.nil?
-          compile_stag(token, out, scanner)
-        else
-          compile_etag(token, out, scanner)
-        end
-      end
-      add_put_cmd(out, content) if content.size > 0
-      out.close
-      return out.script, *magic_comment
-    end
-
-    def compile_stag(stag, out, scanner)
-      case stag
-      when PercentLine
-        add_put_cmd(out, content) if content.size > 0
-        self.content = +''
-        out.push(stag.to_s)
-        out.cr
-      when :cr
-        out.cr
-      when '<%', '<%=', '<%#'
-        scanner.stag = stag
-        add_put_cmd(out, content) if content.size > 0
-        self.content = +''
-      when "\n"
-        content << "\n"
-        add_put_cmd(out, content)
-        self.content = +''
-      when '<%%'
-        content << '<%'
-      else
-        content << stag
-      end
-    end
-
-    def compile_etag(etag, out, scanner)
-      case etag
-      when '%>'
-        compile_content(scanner.stag, out)
-        scanner.stag = nil
-        self.content = +''
-      when '%%>'
-        content << '%>'
-      else
-        content << etag
-      end
-    end
-
-    def compile_content(stag, out)
-      case stag
-      when '<%'
-        if content[-1] == ?\n
-          content.chop!
-          out.push(content)
-          out.cr
-        else
-          out.push(content)
-        end
-      when '<%='
-        add_insert_cmd(out, content)
-      when '<%#'
-        # commented out
-      end
-    end
-
-    def prepare_trim_mode(mode) # :nodoc:
-      case mode
-      when 1
-        return [false, '>']
-      when 2
-        return [false, '<>']
-      when 0, nil
-        return [false, nil]
-      when String
-        unless mode.match?(/\A(%|-|>|<>){1,2}\z/)
-          warn_invalid_trim_mode(mode, uplevel: 5)
-        end
-
-        perc = mode.include?('%')
-        if mode.include?('-')
-          return [perc, '-']
-        elsif mode.include?('<>')
-          return [perc, '<>']
-        elsif mode.include?('>')
-          return [perc, '>']
-        else
-          [perc, nil]
-        end
-      else
-        warn_invalid_trim_mode(mode, uplevel: 5)
-        return [false, nil]
-      end
-    end
-
-    def make_scanner(src) # :nodoc:
-      Scanner.make_scanner(src, @trim_mode, @percent)
-    end
-
-    # Construct a new compiler using the trim_mode. See ERB::new for available
-    # trim modes.
-    def initialize(trim_mode)
-      @percent, @trim_mode = prepare_trim_mode(trim_mode)
-      @put_cmd = 'print'
-      @insert_cmd = @put_cmd
-      @pre_cmd = []
-      @post_cmd = []
-    end
-    attr_reader :percent, :trim_mode
-
-    # The command to handle text that ends with a newline
-    attr_accessor :put_cmd
-
-    # The command to handle text that is inserted prior to a newline
-    attr_accessor :insert_cmd
-
-    # An array of commands prepended to compiled code
-    attr_accessor :pre_cmd
-
-    # An array of commands appended to compiled code
-    attr_accessor :post_cmd
-
-    private
-
-    # A buffered text in #compile
-    attr_accessor :content
-
-    def detect_magic_comment(s, enc = nil)
-      re = @percent ? /\G(?:<%#(.*)%>|%#(.*)\n)/ : /\G<%#(.*)%>/
-      frozen = nil
-      s.scan(re) do
-        comment = $+
-        comment = $1 if comment[/-\*-\s*([^\s].*?)\s*-\*-$/]
-        case comment
-        when %r"coding\s*[=:]\s*([[:alnum:]\-_]+)"
-          enc = Encoding.find($1.sub(/-(?:mac|dos|unix)/i, ''))
-        when %r"frozen[-_]string[-_]literal\s*:\s*([[:alnum:]]+)"
-          frozen = $1
-        end
-      end
-      return enc, frozen
-    end
-
-    def warn_invalid_trim_mode(mode, uplevel:)
-      warn "Invalid ERB trim mode: #{mode.inspect} (trim_mode: nil, 0, 1, 2, or String composed of '%' and/or '-', '>', '<>')", uplevel: uplevel + 1
-    end
-  end
-end
-
-#--
-# ERB
-class ERB
   #
   # Constructs a new ERB object with the template specified in _str_.
   #
@@ -980,100 +504,3 @@ class ERB
     cls
   end
 end
-
-#--
-# ERB::Util
-class ERB
-  # A utility module for conversion routines, often handy in HTML generation.
-  module Util
-    public
-    #
-    # A utility method for escaping HTML tag characters in _s_.
-    #
-    #   require "erb"
-    #   include ERB::Util
-    #
-    #   puts html_escape("is a > 0 & a < 10?")
-    #
-    # _Generates_
-    #
-    #   is a &gt; 0 &amp; a &lt; 10?
-    #
-    def html_escape(s)
-      CGI.escapeHTML(s.to_s)
-    end
-    alias h html_escape
-    module_function :h
-    module_function :html_escape
-
-    #
-    # A utility method for encoding the String _s_ as a URL.
-    #
-    #   require "erb"
-    #   include ERB::Util
-    #
-    #   puts url_encode("Programming Ruby:  The Pragmatic Programmer's Guide")
-    #
-    # _Generates_
-    #
-    #   Programming%20Ruby%3A%20%20The%20Pragmatic%20Programmer%27s%20Guide
-    #
-    def url_encode(s)
-      s.to_s.b.gsub(/[^a-zA-Z0-9_\-.~]/n) { |m|
-        sprintf("%%%02X", m.unpack1("C"))
-      }
-    end
-    alias u url_encode
-    module_function :u
-    module_function :url_encode
-  end
-end
-
-#--
-# ERB::DefMethod
-class ERB
-  # Utility module to define eRuby script as instance method.
-  #
-  # === Example
-  #
-  # example.rhtml:
-  #   <% for item in @items %>
-  #   <b><%= item %></b>
-  #   <% end %>
-  #
-  # example.rb:
-  #   require 'erb'
-  #   class MyClass
-  #     extend ERB::DefMethod
-  #     def_erb_method('render()', 'example.rhtml')
-  #     def initialize(items)
-  #       @items = items
-  #     end
-  #   end
-  #   print MyClass.new([10,20,30]).render()
-  #
-  # result:
-  #
-  #   <b>10</b>
-  #
-  #   <b>20</b>
-  #
-  #   <b>30</b>
-  #
-  module DefMethod
-    public
-    # define _methodname_ as instance method of current module, using ERB
-    # object or eRuby file
-    def def_erb_method(methodname, erb_or_fname)
-      if erb_or_fname.kind_of? String
-        fname = erb_or_fname
-        erb = ERB.new(File.read(fname))
-        erb.def_method(self, methodname, fname)
-      else
-        erb = erb_or_fname
-        erb.def_method(self, methodname, erb.filename || '(ERB)')
-      end
-    end
-    module_function :def_erb_method
-  end
-end
diff --git a/lib/erb/compiler.rb b/lib/erb/compiler.rb
new file mode 100644
index 0000000000..547d2c4c44
--- /dev/null
+++ b/lib/erb/compiler.rb
@@ -0,0 +1,471 @@
+#--
+# ERB::Compiler
+#
+# Compiles ERB templates into Ruby code; the compiled code produces the
+# template result when evaluated. ERB::Compiler provides hooks to define how
+# generated output is handled.
+#
+# Internally ERB does something like this to generate the code returned by
+# ERB#src:
+#
+#   compiler = ERB::Compiler.new('<>')
+#   compiler.pre_cmd    = ["_erbout=+''"]
+#   compiler.put_cmd    = "_erbout.<<"
+#   compiler.insert_cmd = "_erbout.<<"
+#   compiler.post_cmd   = ["_erbout"]
+#
+#   code, enc = compiler.compile("Got <%= obj %>!\n")
+#   puts code
+#
+# <i>Generates</i>:
+#
+#   #coding:UTF-8
+#   _erbout=+''; _erbout.<< "Got ".freeze; _erbout.<<(( obj ).to_s); _erbout.<< "!\n".freeze; _erbout
+#
+# By default the output is sent to the print method.  For example:
+#
+#   compiler = ERB::Compiler.new('<>')
+#   code, enc = compiler.compile("Got <%= obj %>!\n")
+#   puts code
+#
+# <i>Generates</i>:
+#
+#   #coding:UTF-8
+#   print "Got ".freeze; print(( obj ).to_s); print "!\n".freeze
+#
+# == Evaluation
+#
+# The compiled code can be used in any context where the names in the code
+# correctly resolve. Using the last example, each of these print 'Got It!'
+#
+# Evaluate using a variable:
+#
+#   obj = 'It'
+#   eval code
+#
+# Evaluate using an input:
+#
+#   mod = Module.new
+#   mod.module_eval %{
+#     def get(obj)
+#       #{code}
+#     end
+#   }
+#   extend mod
+#   get('It')
+#
+# Evaluate using an accessor:
+#
+#   klass = Class.new Object
+#   klass.class_eval %{
+#     attr_accessor :obj
+#     def initialize(obj)
+#       @obj = obj
+#     end
+#     def get_it
+#       #{code}
+#     end
+#   }
+#   klass.new('It').get_it
+#
+# Good! See also ERB#def_method, ERB#def_module, and ERB#def_class.
+class ERB::Compiler # :nodoc:
+  class PercentLine # :nodoc:
+    def initialize(str)
+      @value = str
+    end
+    attr_reader :value
+    alias :to_s :value
+  end
+
+  class Scanner # :nodoc:
+    @scanner_map = {}
+    class << self
+      def register_scanner(klass, trim_mode, percent)
+        @scanner_map[[trim_mode, percent]] = klass
+      end
+      alias :regist_scanner :register_scanner
+    end
+
+    def self.default_scanner=(klass)
+      @default_scanner = klass
+    end
+
+    def self.make_scanner(src, trim_mode, percent)
+      klass = @scanner_map.fetch([trim_mode, percent], @default_scanner)
+      klass.new(src, trim_mode, percent)
+    end
+
+    DEFAULT_STAGS = %w(<%% <%= <%# <%).freeze
+    DEFAULT_ETAGS = %w(%%> %>).freeze
+    def initialize(src, trim_mode, percent)
+      @src = src
+      @stag = nil
+      @stags = DEFAULT_STAGS
+      @etags = DEFAULT_ETAGS
+    end
+    attr_accessor :stag
+    attr_reader :stags, :etags
+
+    def scan; end
+  end
+
+  class TrimScanner < Scanner # :nodoc:
+    def initialize(src, trim_mode, percent)
+      super
+      @trim_mode = trim_mode
+      @percent = percent
+      if @trim_mode == '>'
+        @scan_reg  = /(.*?)(%>\r?\n|#{(stags + etags).join('|')}|\n|\z)/m
+        @scan_line = self.method(:trim_line1)
+      elsif @trim_mode == '<>'
+        @scan_reg  = /(.*?)(%>\r?\n|#{(stags + etags).join('|')}|\n|\z)/m
+        @scan_line = self.method(:trim_line2)
+      elsif @trim_mode == '-'
+        @scan_reg  = /(.*?)(^[ \t]*<%\-|<%\-|-%>\r?\n|-%>|#{(stags + etags).join('|')}|\z)/m
+        @scan_line = self.method(:explicit_trim_line)
+      else
+        @scan_reg  = /(.*?)(#{(stags + etags).join('|')}|\n|\z)/m
+        @scan_line = self.method(:scan_line)
+      end
+    end
+
+    def scan(&block)
+      @stag = nil
+      if @percent
+        @src.each_line do |line|
+          percent_line(line, &block)
+        end
+      else
+        @scan_line.call(@src, &block)
+      end
+      nil
+    end
+
+    def percent_line(line, &block)
+      if @stag || line[0] != ?%
+        return @scan_line.call(line, &block)
+      end
+
+      line[0] = ''
+      if line[0] == ?%
+        @scan_line.call(line, &block)
+      else
+        yield(PercentLine.new(line.chomp))
+      end
+    end
+
+    def scan_line(line)
+      line.scan(@scan_reg) do |tokens|
+        tokens.each do |token|
+          next if token.empty?
+          yield(token)
+        end
+      end
+    end
+
+    def trim_line1(line)
+      line.scan(@scan_reg) do |tokens|
+        tokens.each do |token|
+          next if token.empty?
+          if token == "%>\n" || token == "%>\r\n"
+            yield('%>')
+            yield(:cr)
+          else
+            yield(token)
+          end
+        end
+      end
+    end
+
+    def trim_line2(line)
+      head = nil
+      line.scan(@scan_reg) do |tokens|
+        tokens.each do |token|
+          next if token.empty?
+          head = token unless head
+          if token == "%>\n" || token == "%>\r\n"
+            yield('%>')
+            if is_erb_stag?(head)
+              yield(:cr)
+            else
+              yield("\n")
+            end
+            head = nil
+          else
+            yield(token)
+            head = nil if token == "\n"
+          end
+        end
+      end
+    end
+
+    def explicit_trim_line(line)
+      line.scan(@scan_reg) do |tokens|
+        tokens.each do |token|
+          next if token.empty?
+          if @stag.nil? && /[ \t]*<%-/ =~ token
+            yield('<%')
+          elsif @stag && (token == "-%>\n" || token == "-%>\r\n")
+            yield('%>')
+            yield(:cr)
+          elsif @stag && token == '-%>'
+            yield('%>')
+          else
+            yield(token)
+          end
+        end
+      end
+    end
+
+    ERB_STAG = %w(<%= <%# <%)
+    def is_erb_stag?(s)
+      ERB_STAG.member?(s)
+    end
+  end
+
+  Scanner.default_scanner = TrimScanner
+
+  begin
+    require 'strscan'
+  rescue LoadError
+  else
+    class SimpleScanner < Scanner # :nodoc:
+      def scan
+        stag_reg = (stags == DEFAULT_STAGS) ? /(.*?)(<%[%=#]?|\z)/m : /(.*?)(#{stags.join('|')}|\z)/m
+        etag_reg = (etags == DEFAULT_ETAGS) ? /(.*?)(%%?>|\z)/m : /(.*?)(#{etags.join('|')}|\z)/m
+        scanner = StringScanner.new(@src)
+        while ! scanner.eos?
+          scanner.scan(@stag ? etag_reg : stag_reg)
+          yield(scanner[1])
+          yield(scanner[2])
+        end
+      end
+    end
+    Scanner.register_scanner(SimpleScanner, nil, false)
+
+    class ExplicitScanner < Scanner # :nodoc:
+      def scan
+        stag_reg = /(.*?)(^[ \t]*<%-|<%-|#{stags.join('|')}|\z)/m
+        etag_reg = /(.*?)(-%>|#{etags.join('|')}|\z)/m
+        scanner = StringScanner.new(@src)
+        while ! scanner.eos?
+          scanner.scan(@stag ? etag_reg : stag_reg)
+          yield(scanner[1])
+
+          elem = scanner[2]
+          if /[ \t]*<%-/ =~ elem
+            yield('<%')
+          elsif elem == '-%>'
+            yield('%>')
+            yield(:cr) if scanner.scan(/(\r?\n|\z)/)
+          else
+            yield(elem)
+          end
+        end
+      end
+    end
+    Scanner.register_scanner(ExplicitScanner, '-', false)
+  end
+
+  class Buffer # :nodoc:
+    def initialize(compiler, enc=nil, frozen=nil)
+      @compiler = compiler
+      @line = []
+      @script = +''
+      @script << "#coding:#{enc}\n" if enc
+      @script << "#frozen-string-literal:#{frozen}\n" unless frozen.nil?
+      @compiler.pre_cmd.each do |x|
+        push(x)
+      end
+    end
+    attr_reader :script
+
+    def push(cmd)
+      @line << cmd
+    end
+
+    def cr
+      @script << (@line.join('; '))
+      @line = []
+      @script << "\n"
+    end
+
+    def close
+      return unless @line
+      @compiler.post_cmd.each do |x|
+        push(x)
+      end
+      @script << (@line.join('; '))
+      @line = nil
+    end
+  end
+
+  def add_put_cmd(out, content)
+    out.push("#{@put_cmd} #{content.dump}.freeze#{"\n" * content.count("\n")}")
+  end
+
+  def add_insert_cmd(out, content)
+    out.push("#{@insert_cmd}((#{content}).to_s)")
+  end
+
+  # Compiles an ERB template into Ruby code.  Returns an array of the code
+  # and encoding like ["code", Encoding].
+  def compile(s)
+    enc = s.encoding
+    raise ArgumentError, "#{enc} is not ASCII compatible" if enc.dummy?
+    s = s.b # see String#b
+    magic_comment = detect_magic_comment(s, enc)
+    out = Buffer.new(self, *magic_comment)
+
+    self.content = +''
+    scanner = make_scanner(s)
+    scanner.scan do |token|
+      next if token.nil?
+      next if token == ''
+      if scanner.stag.nil?
+        compile_stag(token, out, scanner)
+      else
+        compile_etag(token, out, scanner)
+      end
+    end
+    add_put_cmd(out, content) if content.size > 0
+    out.close
+    return out.script, *magic_comment
+  end
+
+  def compile_stag(stag, out, scanner)
+    case stag
+    when PercentLine
+      add_put_cmd(out, content) if content.size > 0
+      self.content = +''
+      out.push(stag.to_s)
+      out.cr
+    when :cr
+      out.cr
+    when '<%', '<%=', '<%#'
+      scanner.stag = stag
+      add_put_cmd(out, content) if content.size > 0
+      self.content = +''
+    when "\n"
+      content << "\n"
+      add_put_cmd(out, content)
+      self.content = +''
+    when '<%%'
+      content << '<%'
+    else
+      content << stag
+    end
+  end
+
+  def compile_etag(etag, out, scanner)
+    case etag
+    when '%>'
+      compile_content(scanner.stag, out)
+      scanner.stag = nil
+      self.content = +''
+    when '%%>'
+      content << '%>'
+    else
+      content << etag
+    end
+  end
+
+  def compile_content(stag, out)
+    case stag
+    when '<%'
+      if content[-1] == ?\n
+        content.chop!
+        out.push(content)
+        out.cr
+      else
+        out.push(content)
+      end
+    when '<%='
+      add_insert_cmd(out, content)
+    when '<%#'
+      out.push("\n" * content.count("\n")) # only adjust lineno
+    end
+  end
+
+  def prepare_trim_mode(mode) # :nodoc:
+    case mode
+    when 1
+      return [false, '>']
+    when 2
+      return [false, '<>']
+    when 0, nil
+      return [false, nil]
+    when String
+      unless mode.match?(/\A(%|-|>|<>){1,2}\z/)
+        warn_invalid_trim_mode(mode, uplevel: 5)
+      end
+
+      perc = mode.include?('%')
+      if mode.include?('-')
+        return [perc, '-']
+      elsif mode.include?('<>')
+        return [perc, '<>']
+      elsif mode.include?('>')
+        return [perc, '>']
+      else
+        [perc, nil]
+      end
+    else
+      warn_invalid_trim_mode(mode, uplevel: 5)
+      return [false, nil]
+    end
+  end
+
+  def make_scanner(src) # :nodoc:
+    Scanner.make_scanner(src, @trim_mode, @percent)
+  end
+
+  # Construct a new compiler using the trim_mode. See ERB::new for available
+  # trim modes.
+  def initialize(trim_mode)
+    @percent, @trim_mode = prepare_trim_mode(trim_mode)
+    @put_cmd = 'print'
+    @insert_cmd = @put_cmd
+    @pre_cmd = []
+    @post_cmd = []
+  end
+  attr_reader :percent, :trim_mode
+
+  # The command to handle text that ends with a newline
+  attr_accessor :put_cmd
+
+  # The command to handle text that is inserted prior to a newline
+  attr_accessor :insert_cmd
+
+  # An array of commands prepended to compiled code
+  attr_accessor :pre_cmd
+
+  # An array of commands appended to compiled code
+  attr_accessor :post_cmd
+
+  private
+
+  # A buffered text in #compile
+  attr_accessor :content
+
+  def detect_magic_comment(s, enc = nil)
+    re = @percent ? /\G(?:<%#(.*)%>|%#(.*)\n)/ : /\G<%#(.*)%>/
+    frozen = nil
+    s.scan(re) do
+      comment = $+
+      comment = $1 if comment[/-\*-\s*([^\s].*?)\s*-\*-$/]
+      case comment
+      when %r"coding\s*[=:]\s*([[:alnum:]\-_]+)"
+        enc = Encoding.find($1.sub(/-(?:mac|dos|unix)/i, ''))
+      when %r"frozen[-_]string[-_]literal\s*:\s*([[:alnum:]]+)"
+        frozen = $1
+      end
+    end
+    return enc, frozen
+  end
+
+  def warn_invalid_trim_mode(mode, uplevel:)
+    warn "Invalid ERB trim mode: #{mode.inspect} (trim_mode: nil, 0, 1, 2, or String composed of '%' and/or '-', '>', '<>')", uplevel: uplevel + 1
+  end
+end
diff --git a/lib/erb/def_method.rb b/lib/erb/def_method.rb
new file mode 100644
index 0000000000..17f9c0f9fa
--- /dev/null
+++ b/lib/erb/def_method.rb
@@ -0,0 +1,46 @@
+#--
+# ERB::DefMethod
+#
+# Utility module to define eRuby script as instance method.
+#
+# === Example
+#
+# example.rhtml:
+#   <% for item in @items %>
+#   <b><%= item %></b>
+#   <% end %>
+#
+# example.rb:
+#   require 'erb'
+#   class MyClass
+#     extend ERB::DefMethod
+#     def_erb_method('render()', 'example.rhtml')
+#     def initialize(items)
+#       @items = items
+#     end
+#   end
+#   print MyClass.new([10,20,30]).render()
+#
+# result:
+#
+#   <b>10</b>
+#
+#   <b>20</b>
+#
+#   <b>30</b>
+#
+module ERB::DefMethod
+  # define _methodname_ as instance method of current module, using ERB
+  # object or eRuby file
+  def def_erb_method(methodname, erb_or_fname)
+    if erb_or_fname.kind_of? String
+      fname = erb_or_fname
+      erb = ERB.new(File.read(fname))
+      erb.def_method(self, methodname, fname)
+    else
+      erb = erb_or_fname
+      erb.def_method(self, methodname, erb.filename || '(ERB)')
+    end
+  end
+  module_function :def_erb_method
+end
diff --git a/lib/erb/util.rb b/lib/erb/util.rb
new file mode 100644
index 0000000000..0c1e7482a8
--- /dev/null
+++ b/lib/erb/util.rb
@@ -0,0 +1,62 @@
+#--
+# ERB::Escape
+#
+# A subset of ERB::Util. Unlike ERB::Util#html_escape, we expect/hope
+# Rails will not monkey-patch ERB::Escape#html_escape.
+begin
+  # We don't build the C extension for JRuby, TruffleRuby, and WASM
+  if $LOAD_PATH.resolve_feature_path('erb/escape')
+    require 'erb/escape'
+  end
+rescue LoadError # resolve_feature_path raises LoadError on TruffleRuby 22.3.0
+end
+unless defined?(ERB::Escape)
+  module ERB::Escape
+    def html_escape(s)
+      CGI.escapeHTML(s.to_s)
+    end
+    module_function :html_escape
+  end
+end
+
+#--
+# ERB::Util
+#
+# A utility module for conversion routines, often handy in HTML generation.
+module ERB::Util
+  #
+  # A utility method for escaping HTML tag characters in _s_.
+  #
+  #   require "erb"
+  #   include ERB::Util
+  #
+  #   puts html_escape("is a > 0 & a < 10?")
+  #
+  # _Generates_
+  #
+  #   is a &gt; 0 &amp; a &lt; 10?
+  #
+  include ERB::Escape # html_escape
+  module_function :html_escape
+  alias h html_escape
+  module_function :h
+
+  #
+  # A utility method for encoding the String _s_ as a URL.
+  #
+  #   require "erb"
+  #   include ERB::Util
+  #
+  #   puts url_encode("Programming Ruby:  The Pragmatic Programmer's Guide")
+  #
+  # _Generates_
+  #
+  #   Programming%20Ruby%3A%20%20The%20Pragmatic%20Programmer%27s%20Guide
+  #
+  def url_encode(s)
+    CGI.escapeURIComponent(s.to_s)
+  end
+  alias u url_encode
+  module_function :u
+  module_function :url_encode
+end
diff --git a/lib/erb/version.rb b/lib/erb/version.rb
index 0aaa38258f..38e1b76ff4 100644
--- a/lib/erb/version.rb
+++ b/lib/erb/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 class ERB
-  VERSION = '2.2.3'
+  VERSION = '4.0.2'
   private_constant :VERSION
 end
diff --git a/lib/error_highlight/base.rb b/lib/error_highlight/base.rb
index 8392979e24..062871ee16 100644
--- a/lib/error_highlight/base.rb
+++ b/lib/error_highlight/base.rb
@@ -1,12 +1,17 @@
 require_relative "version"
 
 module ErrorHighlight
-  # Identify the code fragment that seems associated with a given error
+  # Identify the code fragment at that a given exception occurred.
   #
-  # Arguments:
-  #  node: RubyVM::AbstractSyntaxTree::Node (script_lines should be enabled)
-  #  point_type: :name | :args
-  #  name: The name associated with the NameError/NoMethodError
+  # Options:
+  #
+  # point_type: :name | :args
+  #   :name (default) points the method/variable name that the exception occurred.
+  #   :args points the arguments of the method call that the exception occurred.
+  #
+  # backtrace_location: Thread::Backtrace::Location
+  #   It locates the code fragment of the given backtrace_location.
+  #   By default, it uses the first frame of backtrace_locations of the given exception.
   #
   # Returns:
   #  {
@@ -15,9 +20,56 @@ module ErrorHighlight
   #    last_lineno: Integer,
   #    last_column: Integer,
   #    snippet: String,
+  #    script_lines: [String],
   #  } | nil
-  def self.spot(...)
-    Spotter.new(...).spot
+  #
+  # Limitations:
+  #
+  # Currently, ErrorHighlight.spot only supports a single-line code fragment.
+  # Therefore, if the return value is not nil, first_lineno and last_lineno will have
+  # the same value. If the relevant code fragment spans multiple lines
+  # (e.g., Array#[] of +ary[(newline)expr(newline)]+), the method will return nil.
+  # This restriction may be removed in the future.
+  def self.spot(obj, **opts)
+    case obj
+    when Exception
+      exc = obj
+      loc = opts[:backtrace_location]
+      opts = { point_type: opts.fetch(:point_type, :name) }
+
+      unless loc
+        case exc
+        when TypeError, ArgumentError
+          opts[:point_type] = :args
+        end
+
+        locs = exc.backtrace_locations
+        return nil unless locs
+
+        loc = locs.first
+        return nil unless loc
+
+        opts[:name] = exc.name if NameError === obj
+      end
+
+      return nil unless Thread::Backtrace::Location === loc
+
+      node = RubyVM::AbstractSyntaxTree.of(loc, keep_script_lines: true)
+
+      Spotter.new(node, **opts).spot
+
+    when RubyVM::AbstractSyntaxTree::Node
+      Spotter.new(obj, **opts).spot
+
+    else
+      raise TypeError, "Exception is expected"
+    end
+
+  rescue SyntaxError,
+         SystemCallError, # file not found or something
+         ArgumentError # eval'ed code
+
+    return nil
   end
 
   class Spotter
@@ -122,6 +174,7 @@ module ErrorHighlight
           last_lineno: @end_lineno,
           last_column: @end_column,
           snippet: @snippet,
+          script_lines: @node.script_lines,
         }
       else
         return nil
diff --git a/lib/error_highlight/core_ext.rb b/lib/error_highlight/core_ext.rb
index 78cda8ace2..b69093f74e 100644
--- a/lib/error_highlight/core_ext.rb
+++ b/lib/error_highlight/core_ext.rb
@@ -2,52 +2,46 @@ require_relative "formatter"
 
 module ErrorHighlight
   module CoreExt
-    # This is a marker to let `DidYouMean::Correctable#original_message` skip
-    # the following method definition of `to_s`.
-    # See https://github.com/ruby/did_you_mean/pull/152
-    SKIP_TO_S_FOR_SUPER_LOOKUP = true
-    private_constant :SKIP_TO_S_FOR_SUPER_LOOKUP
-
-    def to_s
-      msg = super.dup
-
-      locs = backtrace_locations
-      return msg unless locs
-
-      loc = locs.first
-      return msg unless loc
-      begin
-        node = RubyVM::AbstractSyntaxTree.of(loc, keep_script_lines: true)
-        opts = {}
+    private def generate_snippet
+      spot = ErrorHighlight.spot(self)
+      return "" unless spot
+      return ErrorHighlight.formatter.message_for(spot)
+    end
 
-        case self
-        when NoMethodError, NameError
-          opts[:point_type] = :name
-          opts[:name] = name
-        when TypeError, ArgumentError
-          opts[:point_type] = :args
+    if Exception.method_defined?(:detailed_message)
+      def detailed_message(highlight: false, error_highlight: true, **)
+        return super unless error_highlight
+        snippet = generate_snippet
+        if highlight
+          snippet = snippet.gsub(/.+/) { "\e[1m" + $& + "\e[m" }
         end
-
-        spot = ErrorHighlight.spot(node, **opts)
-
-      rescue SyntaxError
-      rescue SystemCallError # file not found or something
-      rescue ArgumentError   # eval'ed code
+        super + snippet
       end
-
-      if spot
-        points = ErrorHighlight.formatter.message_for(spot)
-        msg << points if !msg.include?(points)
+    else
+      # This is a marker to let `DidYouMean::Correctable#original_message` skip
+      # the following method definition of `to_s`.
+      # See https://github.com/ruby/did_you_mean/pull/152
+      SKIP_TO_S_FOR_SUPER_LOOKUP = true
+      private_constant :SKIP_TO_S_FOR_SUPER_LOOKUP
+
+      def to_s
+        msg = super
+        snippet = generate_snippet
+        if snippet != "" && !msg.include?(snippet)
+          msg + snippet
+        else
+          msg
+        end
       end
-
-      msg
     end
   end
 
   NameError.prepend(CoreExt)
 
-  # The extension for TypeError/ArgumentError is temporarily disabled due to many test failures
-
-  #TypeError.prepend(CoreExt)
-  #ArgumentError.prepend(CoreExt)
+  if Exception.method_defined?(:detailed_message)
+    # ErrorHighlight is enabled for TypeError and ArgumentError only when Exception#detailed_message is available.
+    # This is because changing ArgumentError#message is highly incompatible.
+    TypeError.prepend(CoreExt)
+    ArgumentError.prepend(CoreExt)
+  end
 end
diff --git a/lib/error_highlight/version.rb b/lib/error_highlight/version.rb
index 49a34502cb..5afe5f06d6 100644
--- a/lib/error_highlight/version.rb
+++ b/lib/error_highlight/version.rb
@@ -1,3 +1,3 @@
 module ErrorHighlight
-  VERSION = "0.3.0"
+  VERSION = "0.5.1"
 end
diff --git a/lib/fileutils.rb b/lib/fileutils.rb
index c115005163..b495078f93 100644
--- a/lib/fileutils.rb
+++ b/lib/fileutils.rb
@@ -6,103 +6,181 @@ rescue LoadError
   # for make mjit-headers
 end
 
+# Namespace for file utility methods for copying, moving, removing, etc.
 #
-# = fileutils.rb
+# == What's Here
 #
-# Copyright (c) 2000-2007 Minero Aoki
+# First, what’s elsewhere. \Module \FileUtils:
 #
-# This program is free software.
-# You can distribute/modify this program under the same terms of ruby.
+# - Inherits from {class Object}[rdoc-ref:Object].
+# - Supplements {class File}[rdoc-ref:File]
+#   (but is not included or extended there).
 #
-# == module FileUtils
+# Here, module \FileUtils provides methods that are useful for:
 #
-# Namespace for several file utility methods for copying, moving, removing, etc.
+# - {Creating}[rdoc-ref:FileUtils@Creating].
+# - {Deleting}[rdoc-ref:FileUtils@Deleting].
+# - {Querying}[rdoc-ref:FileUtils@Querying].
+# - {Setting}[rdoc-ref:FileUtils@Setting].
+# - {Comparing}[rdoc-ref:FileUtils@Comparing].
+# - {Copying}[rdoc-ref:FileUtils@Copying].
+# - {Moving}[rdoc-ref:FileUtils@Moving].
+# - {Options}[rdoc-ref:FileUtils@Options].
 #
-# === Module Functions
+# === Creating
 #
-#   require 'fileutils'
+# - ::mkdir: Creates directories.
+# - ::mkdir_p, ::makedirs, ::mkpath: Creates directories,
+#   also creating ancestor directories as needed.
+# - ::link_entry: Creates a hard link.
+# - ::ln, ::link: Creates hard links.
+# - ::ln_s, ::symlink: Creates symbolic links.
+# - ::ln_sf: Creates symbolic links, overwriting if necessary.
+# - ::ln_sr: Creates symbolic links relative to targets
 #
-#   FileUtils.cd(dir, **options)
-#   FileUtils.cd(dir, **options) {|dir| block }
-#   FileUtils.pwd()
-#   FileUtils.mkdir(dir, **options)
-#   FileUtils.mkdir(list, **options)
-#   FileUtils.mkdir_p(dir, **options)
-#   FileUtils.mkdir_p(list, **options)
-#   FileUtils.rmdir(dir, **options)
-#   FileUtils.rmdir(list, **options)
-#   FileUtils.ln(target, link, **options)
-#   FileUtils.ln(targets, dir, **options)
-#   FileUtils.ln_s(target, link, **options)
-#   FileUtils.ln_s(targets, dir, **options)
-#   FileUtils.ln_sf(target, link, **options)
-#   FileUtils.cp(src, dest, **options)
-#   FileUtils.cp(list, dir, **options)
-#   FileUtils.cp_r(src, dest, **options)
-#   FileUtils.cp_r(list, dir, **options)
-#   FileUtils.mv(src, dest, **options)
-#   FileUtils.mv(list, dir, **options)
-#   FileUtils.rm(list, **options)
-#   FileUtils.rm_r(list, **options)
-#   FileUtils.rm_rf(list, **options)
-#   FileUtils.install(src, dest, **options)
-#   FileUtils.chmod(mode, list, **options)
-#   FileUtils.chmod_R(mode, list, **options)
-#   FileUtils.chown(user, group, list, **options)
-#   FileUtils.chown_R(user, group, list, **options)
-#   FileUtils.touch(list, **options)
+# === Deleting
 #
-# Possible <tt>options</tt> are:
+# - ::remove_dir: Removes a directory and its descendants.
+# - ::remove_entry: Removes an entry, including its descendants if it is a directory.
+# - ::remove_entry_secure: Like ::remove_entry, but removes securely.
+# - ::remove_file: Removes a file entry.
+# - ::rm, ::remove: Removes entries.
+# - ::rm_f, ::safe_unlink: Like ::rm, but removes forcibly.
+# - ::rm_r: Removes entries and their descendants.
+# - ::rm_rf, ::rmtree: Like ::rm_r, but removes forcibly.
+# - ::rmdir: Removes directories.
 #
-# <tt>:force</tt> :: forced operation (rewrite files if exist, remove
-#                    directories if not empty, etc.);
-# <tt>:verbose</tt> :: print command to be run, in bash syntax, before
-#                      performing it;
-# <tt>:preserve</tt> :: preserve object's group, user and modification
-#                       time on copying;
-# <tt>:noop</tt> :: no changes are made (usable in combination with
-#                   <tt>:verbose</tt> which will print the command to run)
+# === Querying
 #
-# Each method documents the options that it honours. See also ::commands,
-# ::options and ::options_of methods to introspect which command have which
-# options.
+# - ::pwd, ::getwd: Returns the path to the working directory.
+# - ::uptodate?: Returns whether a given entry is newer than given other entries.
 #
-# All methods that have the concept of a "source" file or directory can take
-# either one file or a list of files in that argument.  See the method
-# documentation for examples.
+# === Setting
 #
-# There are some `low level' methods, which do not accept keyword arguments:
+# - ::cd, ::chdir: Sets the working directory.
+# - ::chmod: Sets permissions for an entry.
+# - ::chmod_R: Sets permissions for an entry and its descendants.
+# - ::chown: Sets the owner and group for entries.
+# - ::chown_R: Sets the owner and group for entries and their descendants.
+# - ::touch: Sets modification and access times for entries,
+#   creating if necessary.
 #
-#   FileUtils.copy_entry(src, dest, preserve = false, dereference_root = false, remove_destination = false)
-#   FileUtils.copy_file(src, dest, preserve = false, dereference = true)
-#   FileUtils.copy_stream(srcstream, deststream)
-#   FileUtils.remove_entry(path, force = false)
-#   FileUtils.remove_entry_secure(path, force = false)
-#   FileUtils.remove_file(path, force = false)
-#   FileUtils.compare_file(path_a, path_b)
-#   FileUtils.compare_stream(stream_a, stream_b)
-#   FileUtils.uptodate?(file, cmp_list)
+# === Comparing
 #
-# == module FileUtils::Verbose
+# - ::compare_file, ::cmp, ::identical?: Returns whether two entries are identical.
+# - ::compare_stream: Returns whether two streams are identical.
 #
-# This module has all methods of FileUtils module, but it outputs messages
-# before acting.  This equates to passing the <tt>:verbose</tt> flag to methods
-# in FileUtils.
+# === Copying
 #
-# == module FileUtils::NoWrite
+# - ::copy_entry: Recursively copies an entry.
+# - ::copy_file: Copies an entry.
+# - ::copy_stream: Copies a stream.
+# - ::cp, ::copy: Copies files.
+# - ::cp_lr: Recursively creates hard links.
+# - ::cp_r: Recursively copies files, retaining mode, owner, and group.
+# - ::install: Recursively copies files, optionally setting mode,
+#   owner, and group.
 #
-# This module has all methods of FileUtils module, but never changes
-# files/directories.  This equates to passing the <tt>:noop</tt> flag to methods
-# in FileUtils.
+# === Moving
 #
-# == module FileUtils::DryRun
+# - ::mv, ::move: Moves entries.
 #
-# This module has all methods of FileUtils module, but never changes
-# files/directories.  This equates to passing the <tt>:noop</tt> and
-# <tt>:verbose</tt> flags to methods in FileUtils.
+# === Options
+#
+# - ::collect_method: Returns the names of methods that accept a given option.
+# - ::commands: Returns the names of methods that accept options.
+# - ::have_option?: Returns whether a given method accepts a given option.
+# - ::options: Returns all option names.
+# - ::options_of: Returns the names of the options for a given method.
+#
+# == Path Arguments
+#
+# Some methods in \FileUtils accept _path_ arguments,
+# which are interpreted as paths to filesystem entries:
+#
+# - If the argument is a string, that value is the path.
+# - If the argument has method +:to_path+, it is converted via that method.
+# - If the argument has method +:to_str+, it is converted via that method.
+#
+# == About the Examples
+#
+# Some examples here involve trees of file entries.
+# For these, we sometimes display trees using the
+# {tree command-line utility}[https://en.wikipedia.org/wiki/Tree_(command)],
+# which is a recursive directory-listing utility that produces
+# a depth-indented listing of files and directories.
+#
+# We use a helper method to launch the command and control the format:
+#
+#   def tree(dirpath = '.')
+#     command = "tree --noreport --charset=ascii #{dirpath}"
+#     system(command)
+#   end
+#
+# To illustrate:
+#
+#   tree('src0')
+#   # => src0
+#   #    |-- sub0
+#   #    |   |-- src0.txt
+#   #    |   `-- src1.txt
+#   #    `-- sub1
+#   #        |-- src2.txt
+#   #        `-- src3.txt
+#
+# == Avoiding the TOCTTOU Vulnerability
+#
+# For certain methods that recursively remove entries,
+# there is a potential vulnerability called the
+# {Time-of-check to time-of-use}[https://en.wikipedia.org/wiki/Time-of-check_to_time-of-use],
+# or TOCTTOU, vulnerability that can exist when:
+#
+# - An ancestor directory of the entry at the target path is world writable;
+#   such directories include <tt>/tmp</tt>.
+# - The directory tree at the target path includes:
+#
+#   - A world-writable descendant directory.
+#   - A symbolic link.
+#
+# To avoid that vulnerability, you can use this method to remove entries:
+#
+# - FileUtils.remove_entry_secure: removes recursively
+#   if the target path points to a directory.
+#
+# Also available are these methods,
+# each of which calls \FileUtils.remove_entry_secure:
+#
+# - FileUtils.rm_r with keyword argument <tt>secure: true</tt>.
+# - FileUtils.rm_rf with keyword argument <tt>secure: true</tt>.
+#
+# Finally, this method for moving entries calls \FileUtils.remove_entry_secure
+# if the source and destination are on different file systems
+# (which means that the "move" is really a copy and remove):
+#
+# - FileUtils.mv with keyword argument <tt>secure: true</tt>.
+#
+# \Method \FileUtils.remove_entry_secure removes securely
+# by applying a special pre-process:
+#
+# - If the target path points to a directory, this method uses methods
+#   {File#chown}[rdoc-ref:File#chown]
+#   and {File#chmod}[rdoc-ref:File#chmod]
+#   in removing directories.
+# - The owner of the target directory should be either the current process
+#   or the super user (root).
+#
+# WARNING: You must ensure that *ALL* parent directories cannot be
+# moved by other untrusted users.  For example, parent directories
+# should not be owned by untrusted users, and should not be world
+# writable except when the sticky bit is set.
+#
+# For details of this security vulnerability, see Perl cases:
+#
+# - {CVE-2005-0448}[https://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2005-0448].
+# - {CVE-2004-0452}[https://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2004-0452].
 #
 module FileUtils
-  VERSION = "1.6.0"
+  VERSION = "1.7.0"
 
   def self.private_module_function(name)   #:nodoc:
     module_function name
@@ -110,7 +188,13 @@ module FileUtils
   end
 
   #
-  # Returns the name of the current directory.
+  # Returns a string containing the path to the current directory:
+  #
+  #   FileUtils.pwd # => "/rdoc/fileutils"
+  #
+  # FileUtils.getwd is an alias for FileUtils.pwd.
+  #
+  # Related: FileUtils.cd.
   #
   def pwd
     Dir.pwd
@@ -120,19 +204,40 @@ module FileUtils
   alias getwd pwd
   module_function :getwd
 
+  # Changes the working directory to the given +dir+, which
+  # should be {interpretable as a path}[rdoc-ref:FileUtils@Path+Arguments]:
+  #
+  # With no block given,
+  # changes the current directory to the directory at +dir+; returns zero:
+  #
+  #   FileUtils.pwd # => "/rdoc/fileutils"
+  #   FileUtils.cd('..')
+  #   FileUtils.pwd # => "/rdoc"
+  #   FileUtils.cd('fileutils')
+  #
+  # With a block given, changes the current directory to the directory
+  # at +dir+, calls the block with argument +dir+,
+  # and restores the original current directory; returns the block's value:
+  #
+  #   FileUtils.pwd                                     # => "/rdoc/fileutils"
+  #   FileUtils.cd('..') { |arg| [arg, FileUtils.pwd] } # => ["..", "/rdoc"]
+  #   FileUtils.pwd                                     # => "/rdoc/fileutils"
+  #
+  # Keyword arguments:
   #
-  # Changes the current directory to the directory +dir+.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
   #
-  # If this method is called with block, resumes to the previous
-  # working directory after the block execution has finished.
+  #     FileUtils.cd('..')
+  #     FileUtils.cd('fileutils')
   #
-  #   FileUtils.cd('/')  # change directory
+  #   Output:
   #
-  #   FileUtils.cd('/', verbose: true)   # change directory and report it
+  #     cd ..
+  #     cd fileutils
   #
-  #   FileUtils.cd('/') do  # change directory
-  #     # ...               # do something
-  #   end                   # return to original directory
+  # FileUtils.chdir is an alias for FileUtils.cd.
+  #
+  # Related: FileUtils.pwd.
   #
   def cd(dir, verbose: nil, &block) # :yield: dir
     fu_output_message "cd #{dir}" if verbose
@@ -146,11 +251,19 @@ module FileUtils
   module_function :chdir
 
   #
-  # Returns true if +new+ is newer than all +old_list+.
-  # Non-existent files are older than any file.
+  # Returns +true+ if the file at path +new+
+  # is newer than all the files at paths in array +old_list+;
+  # +false+ otherwise.
+  #
+  # Argument +new+ and the elements of +old_list+
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments]:
+  #
+  #   FileUtils.uptodate?('Rakefile', ['Gemfile', 'README.md']) # => true
+  #   FileUtils.uptodate?('Gemfile', ['Rakefile', 'README.md']) # => false
   #
-  #   FileUtils.uptodate?('hello.o', %w(hello.c hello.h)) or \
-  #       system 'make hello.o'
+  # A non-existent file is considered to be infinitely old.
+  #
+  # Related: FileUtils.touch.
   #
   def uptodate?(new, old_list)
     return false unless File.exist?(new)
@@ -170,12 +283,39 @@ module FileUtils
   private_module_function :remove_trailing_slash
 
   #
-  # Creates one or more directories.
+  # Creates directories at the paths in the given +list+
+  # (a single path or an array of paths);
+  # returns +list+ if it is an array, <tt>[list]</tt> otherwise.
+  #
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # With no keyword arguments, creates a directory at each +path+ in +list+
+  # by calling: <tt>Dir.mkdir(path, mode)</tt>;
+  # see {Dir.mkdir}[rdoc-ref:Dir.mkdir]:
+  #
+  #   FileUtils.mkdir(%w[tmp0 tmp1]) # => ["tmp0", "tmp1"]
+  #   FileUtils.mkdir('tmp4')        # => ["tmp4"]
+  #
+  # Keyword arguments:
+  #
+  # - <tt>mode: <i>mode</i></tt> - also calls <tt>File.chmod(mode, path)</tt>;
+  #   see {File.chmod}[rdoc-ref:File.chmod].
+  # - <tt>noop: true</tt> - does not create directories.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
   #
-  #   FileUtils.mkdir 'test'
-  #   FileUtils.mkdir %w(tmp data)
-  #   FileUtils.mkdir 'notexist', noop: true  # Does not really create.
-  #   FileUtils.mkdir 'tmp', mode: 0700
+  #     FileUtils.mkdir(%w[tmp0 tmp1], verbose: true)
+  #     FileUtils.mkdir(%w[tmp2 tmp3], mode: 0700, verbose: true)
+  #
+  #   Output:
+  #
+  #     mkdir tmp0 tmp1
+  #     mkdir -m 700 tmp2 tmp3
+  #
+  # Raises an exception if any path points to an existing
+  # file or directory, or if for any reason a directory cannot be created.
+  #
+  # Related: FileUtils.mkdir_p.
   #
   def mkdir(list, mode: nil, noop: nil, verbose: nil)
     list = fu_list(list)
@@ -189,19 +329,42 @@ module FileUtils
   module_function :mkdir
 
   #
-  # Creates a directory and all its parent directories.
-  # For example,
+  # Creates directories at the paths in the given +list+
+  # (a single path or an array of paths),
+  # also creating ancestor directories as needed;
+  # returns +list+ if it is an array, <tt>[list]</tt> otherwise.
+  #
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # With no keyword arguments, creates a directory at each +path+ in +list+,
+  # along with any needed ancestor directories,
+  # by calling: <tt>Dir.mkdir(path, mode)</tt>;
+  # see {Dir.mkdir}[rdoc-ref:Dir.mkdir]:
+  #
+  #   FileUtils.mkdir_p(%w[tmp0/tmp1 tmp2/tmp3]) # => ["tmp0/tmp1", "tmp2/tmp3"]
+  #   FileUtils.mkdir_p('tmp4/tmp5')             # => ["tmp4/tmp5"]
+  #
+  # Keyword arguments:
   #
-  #   FileUtils.mkdir_p '/usr/local/lib/ruby'
+  # - <tt>mode: <i>mode</i></tt> - also calls <tt>File.chmod(mode, path)</tt>;
+  #   see {File.chmod}[rdoc-ref:File.chmod].
+  # - <tt>noop: true</tt> - does not create directories.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
   #
-  # causes to make following directories, if they do not exist.
+  #     FileUtils.mkdir_p(%w[tmp0 tmp1], verbose: true)
+  #     FileUtils.mkdir_p(%w[tmp2 tmp3], mode: 0700, verbose: true)
   #
-  # * /usr
-  # * /usr/local
-  # * /usr/local/lib
-  # * /usr/local/lib/ruby
+  #   Output:
   #
-  # You can pass several directories at a time in a list.
+  #     mkdir -p tmp0 tmp1
+  #     mkdir -p -m 700 tmp2 tmp3
+  #
+  # Raises an exception if for any reason a directory cannot be created.
+  #
+  # FileUtils.mkpath and FileUtils.makedirs are aliases for FileUtils.mkdir_p.
+  #
+  # Related: FileUtils.mkdir.
   #
   def mkdir_p(list, mode: nil, noop: nil, verbose: nil)
     list = fu_list(list)
@@ -212,7 +375,7 @@ module FileUtils
       path = remove_trailing_slash(item)
 
       stack = []
-      until File.directory?(path)
+      until File.directory?(path) || File.dirname(path) == path
         stack.push path
         path = File.dirname(path)
       end
@@ -246,12 +409,39 @@ module FileUtils
   private_module_function :fu_mkdir
 
   #
-  # Removes one or more directories.
+  # Removes directories at the paths in the given +list+
+  # (a single path or an array of paths);
+  # returns +list+, if it is an array, <tt>[list]</tt> otherwise.
+  #
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # With no keyword arguments, removes the directory at each +path+ in +list+,
+  # by calling: <tt>Dir.rmdir(path)</tt>;
+  # see {Dir.rmdir}[rdoc-ref:Dir.rmdir]:
+  #
+  #   FileUtils.rmdir(%w[tmp0/tmp1 tmp2/tmp3]) # => ["tmp0/tmp1", "tmp2/tmp3"]
+  #   FileUtils.rmdir('tmp4/tmp5')             # => ["tmp4/tmp5"]
+  #
+  # Keyword arguments:
+  #
+  # - <tt>parents: true</tt> - removes successive ancestor directories
+  #   if empty.
+  # - <tt>noop: true</tt> - does not remove directories.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
   #
-  #   FileUtils.rmdir 'somedir'
-  #   FileUtils.rmdir %w(somedir anydir otherdir)
-  #   # Does not really remove directory; outputs message.
-  #   FileUtils.rmdir 'somedir', verbose: true, noop: true
+  #     FileUtils.rmdir(%w[tmp0/tmp1 tmp2/tmp3], parents: true, verbose: true)
+  #     FileUtils.rmdir('tmp4/tmp5', parents: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     rmdir -p tmp0/tmp1 tmp2/tmp3
+  #     rmdir -p tmp4/tmp5
+  #
+  # Raises an exception if a directory does not exist
+  # or if for any reason a directory cannot be removed.
+  #
+  # Related: {methods for deleting}[rdoc-ref:FileUtils@Deleting].
   #
   def rmdir(list, parents: nil, noop: nil, verbose: nil)
     list = fu_list(list)
@@ -272,26 +462,62 @@ module FileUtils
   end
   module_function :rmdir
 
+  # Creates {hard links}[https://en.wikipedia.org/wiki/Hard_link].
+  #
+  # Arguments +src+ (a single path or an array of paths)
+  # and +dest+ (a single path)
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # When +src+ is the path to an existing file
+  # and +dest+ is the path to a non-existent file,
+  # creates a hard link at +dest+ pointing to +src+; returns zero:
+  #
+  #   Dir.children('tmp0/')                    # => ["t.txt"]
+  #   Dir.children('tmp1/')                    # => []
+  #   FileUtils.ln('tmp0/t.txt', 'tmp1/t.lnk') # => 0
+  #   Dir.children('tmp1/')                    # => ["t.lnk"]
+  #
+  # When +src+ is the path to an existing file
+  # and +dest+ is the path to an existing directory,
+  # creates a hard link at <tt>dest/src</tt> pointing to +src+; returns zero:
   #
-  # :call-seq:
-  #   FileUtils.ln(target, link, force: nil, noop: nil, verbose: nil)
-  #   FileUtils.ln(target,  dir, force: nil, noop: nil, verbose: nil)
-  #   FileUtils.ln(targets, dir, force: nil, noop: nil, verbose: nil)
+  #   Dir.children('tmp2')               # => ["t.dat"]
+  #   Dir.children('tmp3')               # => []
+  #   FileUtils.ln('tmp2/t.dat', 'tmp3') # => 0
+  #   Dir.children('tmp3')               # => ["t.dat"]
   #
-  # In the first form, creates a hard link +link+ which points to +target+.
-  # If +link+ already exists, raises Errno::EEXIST.
-  # But if the +force+ option is set, overwrites +link+.
+  # When +src+ is an array of paths to existing files
+  # and +dest+ is the path to an existing directory,
+  # then for each path +target+ in +src+,
+  # creates a hard link at <tt>dest/target</tt> pointing to +target+;
+  # returns +src+:
   #
-  #   FileUtils.ln 'gcc', 'cc', verbose: true
-  #   FileUtils.ln '/usr/bin/emacs21', '/usr/bin/emacs'
+  #   Dir.children('tmp4/')                               # => []
+  #   FileUtils.ln(['tmp0/t.txt', 'tmp2/t.dat'], 'tmp4/') # => ["tmp0/t.txt", "tmp2/t.dat"]
+  #   Dir.children('tmp4/')                               # => ["t.dat", "t.txt"]
   #
-  # In the second form, creates a link +dir/target+ pointing to +target+.
-  # In the third form, creates several hard links in the directory +dir+,
-  # pointing to each item in +targets+.
-  # If +dir+ is not a directory, raises Errno::ENOTDIR.
+  # Keyword arguments:
   #
-  #   FileUtils.cd '/sbin'
-  #   FileUtils.ln %w(cp mv mkdir), '/bin'   # Now /sbin/cp and /bin/cp are linked.
+  # - <tt>force: true</tt> - overwrites +dest+ if it exists.
+  # - <tt>noop: true</tt> - does not create links.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     FileUtils.ln('tmp0/t.txt', 'tmp1/t.lnk', verbose: true)
+  #     FileUtils.ln('tmp2/t.dat', 'tmp3', verbose: true)
+  #     FileUtils.ln(['tmp0/t.txt', 'tmp2/t.dat'], 'tmp4/', verbose: true)
+  #
+  #   Output:
+  #
+  #     ln tmp0/t.txt tmp1/t.lnk
+  #     ln tmp2/t.dat tmp3
+  #     ln tmp0/t.txt tmp2/t.dat tmp4/
+  #
+  # Raises an exception if +dest+ is the path to an existing file
+  # and keyword argument +force+ is not +true+.
+  #
+  # FileUtils#link is an alias for FileUtils#ln.
+  #
+  # Related: FileUtils.link_entry (has different options).
   #
   def ln(src, dest, force: nil, noop: nil, verbose: nil)
     fu_output_message "ln#{force ? ' -f' : ''} #{[src,dest].flatten.join ' '}" if verbose
@@ -306,28 +532,103 @@ module FileUtils
   alias link ln
   module_function :link
 
-  #
-  # Hard link +src+ to +dest+. If +src+ is a directory, this method links
-  # all its contents recursively. If +dest+ is a directory, links
-  # +src+ to +dest/src+.
-  #
-  # +src+ can be a list of files.
-  #
-  # If +dereference_root+ is true, this method dereference tree root.
-  #
-  # If +remove_destination+ is true, this method removes each destination file before copy.
-  #
-  #   FileUtils.rm_r site_ruby + '/mylib', force: true
-  #   FileUtils.cp_lr 'lib/', site_ruby + '/mylib'
-  #
-  #   # Examples of linking several files to target directory.
-  #   FileUtils.cp_lr %w(mail.rb field.rb debug/), site_ruby + '/tmail'
-  #   FileUtils.cp_lr Dir.glob('*.rb'), '/home/aamine/lib/ruby', noop: true, verbose: true
-  #
-  #   # If you want to link all contents of a directory instead of the
-  #   # directory itself, c.f. src/x -> dest/x, src/y -> dest/y,
-  #   # use the following code.
-  #   FileUtils.cp_lr 'src/.', 'dest'  # cp_lr('src', 'dest') makes dest/src, but this doesn't.
+  # Creates {hard links}[https://en.wikipedia.org/wiki/Hard_link].
+  #
+  # Arguments +src+ (a single path or an array of paths)
+  # and +dest+ (a single path)
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # If +src+ is the path to a directory and +dest+ does not exist,
+  # creates links +dest+ and descendents pointing to +src+ and its descendents:
+  #
+  #   tree('src0')
+  #   # => src0
+  #   #    |-- sub0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- sub1
+  #   #        |-- src2.txt
+  #   #        `-- src3.txt
+  #   File.exist?('dest0') # => false
+  #   FileUtils.cp_lr('src0', 'dest0')
+  #   tree('dest0')
+  #   # => dest0
+  #   #    |-- sub0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- sub1
+  #   #        |-- src2.txt
+  #   #        `-- src3.txt
+  #
+  # If +src+ and +dest+ are both paths to directories,
+  # creates links <tt>dest/src</tt> and descendents
+  # pointing to +src+ and its descendents:
+  #
+  #   tree('src1')
+  #   # => src1
+  #   #    |-- sub0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- sub1
+  #   #        |-- src2.txt
+  #   #        `-- src3.txt
+  #   FileUtils.mkdir('dest1')
+  #   FileUtils.cp_lr('src1', 'dest1')
+  #   tree('dest1')
+  #   # => dest1
+  #   #    `-- src1
+  #   #        |-- sub0
+  #   #        |   |-- src0.txt
+  #   #        |   `-- src1.txt
+  #   #        `-- sub1
+  #   #            |-- src2.txt
+  #   #            `-- src3.txt
+  #
+  # If +src+ is an array of paths to entries and +dest+ is the path to a directory,
+  # for each path +filepath+ in +src+, creates a link at <tt>dest/filepath</tt>
+  # pointing to that path:
+  #
+  #   tree('src2')
+  #   # => src2
+  #   #    |-- sub0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- sub1
+  #   #        |-- src2.txt
+  #   #        `-- src3.txt
+  #   FileUtils.mkdir('dest2')
+  #   FileUtils.cp_lr(['src2/sub0', 'src2/sub1'], 'dest2')
+  #   tree('dest2')
+  #   # => dest2
+  #   #    |-- sub0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- sub1
+  #   #        |-- src2.txt
+  #   #        `-- src3.txt
+  #
+  # Keyword arguments:
+  #
+  # - <tt>dereference_root: false</tt> - if +src+ is a symbolic link,
+  #   does not dereference it.
+  # - <tt>noop: true</tt> - does not create links.
+  # - <tt>remove_destination: true</tt> - removes +dest+ before creating links.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     FileUtils.cp_lr('src0', 'dest0', noop: true, verbose: true)
+  #     FileUtils.cp_lr('src1', 'dest1', noop: true, verbose: true)
+  #     FileUtils.cp_lr(['src2/sub0', 'src2/sub1'], 'dest2', noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     cp -lr src0 dest0
+  #     cp -lr src1 dest1
+  #     cp -lr src2/sub0 src2/sub1 dest2
+  #
+  # Raises an exception if +dest+ is the path to an existing file or directory
+  # and keyword argument <tt>remove_destination: true</tt> is not given.
+  #
+  # Related: {methods for copying}[rdoc-ref:FileUtils@Copying].
   #
   def cp_lr(src, dest, noop: nil, verbose: nil,
             dereference_root: true, remove_destination: false)
@@ -339,27 +640,81 @@ module FileUtils
   end
   module_function :cp_lr
 
+  # Creates {symbolic links}[https://en.wikipedia.org/wiki/Symbolic_link].
+  #
+  # Arguments +src+ (a single path or an array of paths)
+  # and +dest+ (a single path)
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # If +src+ is the path to an existing file:
+  #
+  # - When +dest+ is the path to a non-existent file,
+  #   creates a symbolic link at +dest+ pointing to +src+:
+  #
+  #     FileUtils.touch('src0.txt')
+  #     File.exist?('dest0.txt')   # => false
+  #     FileUtils.ln_s('src0.txt', 'dest0.txt')
+  #     File.symlink?('dest0.txt') # => true
   #
-  # :call-seq:
-  #   FileUtils.ln_s(target, link, force: nil, noop: nil, verbose: nil)
-  #   FileUtils.ln_s(target,  dir, force: nil, noop: nil, verbose: nil)
-  #   FileUtils.ln_s(targets, dir, force: nil, noop: nil, verbose: nil)
+  # - When +dest+ is the path to an existing file,
+  #   creates a symbolic link at +dest+ pointing to +src+
+  #   if and only if keyword argument <tt>force: true</tt> is given
+  #   (raises an exception otherwise):
   #
-  # In the first form, creates a symbolic link +link+ which points to +target+.
-  # If +link+ already exists, raises Errno::EEXIST.
-  # But if the <tt>force</tt> option is set, overwrites +link+.
+  #     FileUtils.touch('src1.txt')
+  #     FileUtils.touch('dest1.txt')
+  #     FileUtils.ln_s('src1.txt', 'dest1.txt', force: true)
+  #     FileTest.symlink?('dest1.txt') # => true
   #
-  #   FileUtils.ln_s '/usr/bin/ruby', '/usr/local/bin/ruby'
-  #   FileUtils.ln_s 'verylongsourcefilename.c', 'c', force: true
+  #     FileUtils.ln_s('src1.txt', 'dest1.txt') # Raises Errno::EEXIST.
   #
-  # In the second form, creates a link +dir/target+ pointing to +target+.
-  # In the third form, creates several symbolic links in the directory +dir+,
-  # pointing to each item in +targets+.
-  # If +dir+ is not a directory, raises Errno::ENOTDIR.
+  # If +dest+ is the path to a directory,
+  # creates a symbolic link at <tt>dest/src</tt> pointing to +src+:
   #
-  #   FileUtils.ln_s Dir.glob('/bin/*.rb'), '/home/foo/bin'
+  #   FileUtils.touch('src2.txt')
+  #   FileUtils.mkdir('destdir2')
+  #   FileUtils.ln_s('src2.txt', 'destdir2')
+  #   File.symlink?('destdir2/src2.txt') # => true
   #
-  def ln_s(src, dest, force: nil, noop: nil, verbose: nil)
+  # If +src+ is an array of paths to existing files and +dest+ is a directory,
+  # for each child +child+ in +src+ creates a symbolic link <tt>dest/child</tt>
+  # pointing to +child+:
+  #
+  #   FileUtils.mkdir('srcdir3')
+  #   FileUtils.touch('srcdir3/src0.txt')
+  #   FileUtils.touch('srcdir3/src1.txt')
+  #   FileUtils.mkdir('destdir3')
+  #   FileUtils.ln_s(['srcdir3/src0.txt', 'srcdir3/src1.txt'], 'destdir3')
+  #   File.symlink?('destdir3/src0.txt') # => true
+  #   File.symlink?('destdir3/src1.txt') # => true
+  #
+  # Keyword arguments:
+  #
+  # - <tt>force: true</tt> - overwrites +dest+ if it exists.
+  # - <tt>relative: false</tt> - create links relative to +dest+.
+  # - <tt>noop: true</tt> - does not create links.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     FileUtils.ln_s('src0.txt', 'dest0.txt', noop: true, verbose: true)
+  #     FileUtils.ln_s('src1.txt', 'destdir1', noop: true, verbose: true)
+  #     FileUtils.ln_s('src2.txt', 'dest2.txt', force: true, noop: true, verbose: true)
+  #     FileUtils.ln_s(['srcdir3/src0.txt', 'srcdir3/src1.txt'], 'destdir3', noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     ln -s src0.txt dest0.txt
+  #     ln -s src1.txt destdir1
+  #     ln -sf src2.txt dest2.txt
+  #     ln -s srcdir3/src0.txt srcdir3/src1.txt destdir3
+  #
+  # FileUtils.symlink is an alias for FileUtils.ln_s.
+  #
+  # Related: FileUtils.ln_sf.
+  #
+  def ln_s(src, dest, force: nil, relative: false, target_directory: true, noop: nil, verbose: nil)
+    if relative
+      return ln_sr(src, dest, force: force, noop: noop, verbose: verbose)
+    end
     fu_output_message "ln -s#{force ? 'f' : ''} #{[src,dest].flatten.join ' '}" if verbose
     return if noop
     fu_each_src_dest0(src, dest) do |s,d|
@@ -372,29 +727,95 @@ module FileUtils
   alias symlink ln_s
   module_function :symlink
 
-  #
-  # :call-seq:
-  #   FileUtils.ln_sf(*args)
-  #
-  # Same as
-  #
-  #   FileUtils.ln_s(*args, force: true)
+  # Like FileUtils.ln_s, but always with keyword argument <tt>force: true</tt> given.
   #
   def ln_sf(src, dest, noop: nil, verbose: nil)
     ln_s src, dest, force: true, noop: noop, verbose: verbose
   end
   module_function :ln_sf
 
+  # Like FileUtils.ln_s, but create links relative to +dest+.
   #
-  # Hard links a file system entry +src+ to +dest+.
-  # If +src+ is a directory, this method links its contents recursively.
+  def ln_sr(src, dest, target_directory: true, force: nil, noop: nil, verbose: nil)
+    options = "#{force ? 'f' : ''}#{target_directory ? '' : 'T'}"
+    dest = File.path(dest)
+    srcs = Array(src)
+    link = proc do |s, target_dir_p = true|
+      s = File.path(s)
+      if target_dir_p
+        d = File.join(destdirs = dest, File.basename(s))
+      else
+        destdirs = File.dirname(d = dest)
+      end
+      destdirs = fu_split_path(File.realpath(destdirs))
+      if fu_starting_path?(s)
+        srcdirs = fu_split_path((File.realdirpath(s) rescue File.expand_path(s)))
+        base = fu_relative_components_from(srcdirs, destdirs)
+        s = File.join(*base)
+      else
+        srcdirs = fu_clean_components(*fu_split_path(s))
+        base = fu_relative_components_from(fu_split_path(Dir.pwd), destdirs)
+        while srcdirs.first&. == ".." and base.last&.!=("..") and !fu_starting_path?(base.last)
+          srcdirs.shift
+          base.pop
+        end
+        s = File.join(*base, *srcdirs)
+      end
+      fu_output_message "ln -s#{options} #{s} #{d}" if verbose
+      next if noop
+      remove_file d, true if force
+      File.symlink s, d
+    end
+    case srcs.size
+    when 0
+    when 1
+      link[srcs[0], target_directory && File.directory?(dest)]
+    else
+      srcs.each(&link)
+    end
+  end
+  module_function :ln_sr
+
+  # Creates {hard links}[https://en.wikipedia.org/wiki/Hard_link]; returns +nil+.
+  #
+  # Arguments +src+ and +dest+
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # If +src+ is the path to a file and +dest+ does not exist,
+  # creates a hard link at +dest+ pointing to +src+:
+  #
+  #   FileUtils.touch('src0.txt')
+  #   File.exist?('dest0.txt') # => false
+  #   FileUtils.link_entry('src0.txt', 'dest0.txt')
+  #   File.file?('dest0.txt')  # => true
   #
-  # Both of +src+ and +dest+ must be a path name.
-  # +src+ must exist, +dest+ must not exist.
+  # If +src+ is the path to a directory and +dest+ does not exist,
+  # recursively creates hard links at +dest+ pointing to paths in +src+:
   #
-  # If +dereference_root+ is true, this method dereferences the tree root.
+  #   FileUtils.mkdir_p(['src1/dir0', 'src1/dir1'])
+  #   src_file_paths = [
+  #     'src1/dir0/t0.txt',
+  #     'src1/dir0/t1.txt',
+  #     'src1/dir1/t2.txt',
+  #     'src1/dir1/t3.txt',
+  #     ]
+  #   FileUtils.touch(src_file_paths)
+  #   File.directory?('dest1')        # => true
+  #   FileUtils.link_entry('src1', 'dest1')
+  #   File.file?('dest1/dir0/t0.txt') # => true
+  #   File.file?('dest1/dir0/t1.txt') # => true
+  #   File.file?('dest1/dir1/t2.txt') # => true
+  #   File.file?('dest1/dir1/t3.txt') # => true
   #
-  # If +remove_destination+ is true, this method removes each destination file before copy.
+  # Keyword arguments:
+  #
+  # - <tt>dereference_root: true</tt> - dereferences +src+ if it is a symbolic link.
+  # - <tt>remove_destination: true</tt> - removes +dest+ before creating links.
+  #
+  # Raises an exception if +dest+ is the path to an existing file or directory
+  # and keyword argument <tt>remove_destination: true</tt> is not given.
+  #
+  # Related: FileUtils.ln (has different options).
   #
   def link_entry(src, dest, dereference_root = false, remove_destination = false)
     Entry_.new(src, nil, dereference_root).traverse do |ent|
@@ -405,16 +826,59 @@ module FileUtils
   end
   module_function :link_entry
 
+  # Copies files.
+  #
+  # Arguments +src+ (a single path or an array of paths)
+  # and +dest+ (a single path)
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
   #
-  # Copies a file content +src+ to +dest+.  If +dest+ is a directory,
-  # copies +src+ to +dest/src+.
+  # If +src+ is the path to a file and +dest+ is not the path to a directory,
+  # copies +src+ to +dest+:
   #
-  # If +src+ is a list of files, then +dest+ must be a directory.
+  #   FileUtils.touch('src0.txt')
+  #   File.exist?('dest0.txt') # => false
+  #   FileUtils.cp('src0.txt', 'dest0.txt')
+  #   File.file?('dest0.txt')  # => true
   #
-  #   FileUtils.cp 'eval.c', 'eval.c.org'
-  #   FileUtils.cp %w(cgi.rb complex.rb date.rb), '/usr/lib/ruby/1.6'
-  #   FileUtils.cp %w(cgi.rb complex.rb date.rb), '/usr/lib/ruby/1.6', verbose: true
-  #   FileUtils.cp 'symlink', 'dest'   # copy content, "dest" is not a symlink
+  # If +src+ is the path to a file and +dest+ is the path to a directory,
+  # copies +src+ to <tt>dest/src</tt>:
+  #
+  #   FileUtils.touch('src1.txt')
+  #   FileUtils.mkdir('dest1')
+  #   FileUtils.cp('src1.txt', 'dest1')
+  #   File.file?('dest1/src1.txt') # => true
+  #
+  # If +src+ is an array of paths to files and +dest+ is the path to a directory,
+  # copies from each +src+ to +dest+:
+  #
+  #   src_file_paths = ['src2.txt', 'src2.dat']
+  #   FileUtils.touch(src_file_paths)
+  #   FileUtils.mkdir('dest2')
+  #   FileUtils.cp(src_file_paths, 'dest2')
+  #   File.file?('dest2/src2.txt') # => true
+  #   File.file?('dest2/src2.dat') # => true
+  #
+  # Keyword arguments:
+  #
+  # - <tt>preserve: true</tt> - preserves file times.
+  # - <tt>noop: true</tt> - does not copy files.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     FileUtils.cp('src0.txt', 'dest0.txt', noop: true, verbose: true)
+  #     FileUtils.cp('src1.txt', 'dest1', noop: true, verbose: true)
+  #     FileUtils.cp(src_file_paths, 'dest2', noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     cp src0.txt dest0.txt
+  #     cp src1.txt dest1
+  #     cp src2.txt src2.dat dest2
+  #
+  # Raises an exception if +src+ is a directory.
+  #
+  # FileUtils.copy is an alias for FileUtils.cp.
+  #
+  # Related: {methods for copying}[rdoc-ref:FileUtils@Copying].
   #
   def cp(src, dest, preserve: nil, noop: nil, verbose: nil)
     fu_output_message "cp#{preserve ? ' -p' : ''} #{[src,dest].flatten.join ' '}" if verbose
@@ -428,30 +892,105 @@ module FileUtils
   alias copy cp
   module_function :copy
 
-  #
-  # Copies +src+ to +dest+. If +src+ is a directory, this method copies
-  # all its contents recursively. If +dest+ is a directory, copies
-  # +src+ to +dest/src+.
-  #
-  # +src+ can be a list of files.
-  #
-  # If +dereference_root+ is true, this method dereference tree root.
-  #
-  # If +remove_destination+ is true, this method removes each destination file before copy.
-  #
-  #   # Installing Ruby library "mylib" under the site_ruby
-  #   FileUtils.rm_r site_ruby + '/mylib', force: true
-  #   FileUtils.cp_r 'lib/', site_ruby + '/mylib'
-  #
-  #   # Examples of copying several files to target directory.
-  #   FileUtils.cp_r %w(mail.rb field.rb debug/), site_ruby + '/tmail'
-  #   FileUtils.cp_r Dir.glob('*.rb'), '/home/foo/lib/ruby', noop: true, verbose: true
-  #
-  #   # If you want to copy all contents of a directory instead of the
-  #   # directory itself, c.f. src/x -> dest/x, src/y -> dest/y,
-  #   # use following code.
-  #   FileUtils.cp_r 'src/.', 'dest'     # cp_r('src', 'dest') makes dest/src,
-  #                                      # but this doesn't.
+  # Recursively copies files.
+  #
+  # Arguments +src+ (a single path or an array of paths)
+  # and +dest+ (a single path)
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # The mode, owner, and group are retained in the copy;
+  # to change those, use FileUtils.install instead.
+  #
+  # If +src+ is the path to a file and +dest+ is not the path to a directory,
+  # copies +src+ to +dest+:
+  #
+  #   FileUtils.touch('src0.txt')
+  #   File.exist?('dest0.txt') # => false
+  #   FileUtils.cp_r('src0.txt', 'dest0.txt')
+  #   File.file?('dest0.txt')  # => true
+  #
+  # If +src+ is the path to a file and +dest+ is the path to a directory,
+  # copies +src+ to <tt>dest/src</tt>:
+  #
+  #   FileUtils.touch('src1.txt')
+  #   FileUtils.mkdir('dest1')
+  #   FileUtils.cp_r('src1.txt', 'dest1')
+  #   File.file?('dest1/src1.txt') # => true
+  #
+  # If +src+ is the path to a directory and +dest+ does not exist,
+  # recursively copies +src+ to +dest+:
+  #
+  #   tree('src2')
+  #   # => src2
+  #   #    |-- dir0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- dir1
+  #   #    |-- src2.txt
+  #   #    `-- src3.txt
+  #   FileUtils.exist?('dest2') # => false
+  #   FileUtils.cp_r('src2', 'dest2')
+  #   tree('dest2')
+  #   # => dest2
+  #   #    |-- dir0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- dir1
+  #   #    |-- src2.txt
+  #   #    `-- src3.txt
+  #
+  # If +src+ and +dest+ are paths to directories,
+  # recursively copies +src+ to <tt>dest/src</tt>:
+  #
+  #   tree('src3')
+  #   # => src3
+  #   #    |-- dir0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- dir1
+  #   #    |-- src2.txt
+  #   #    `-- src3.txt
+  #   FileUtils.mkdir('dest3')
+  #   FileUtils.cp_r('src3', 'dest3')
+  #   tree('dest3')
+  #   # => dest3
+  #   #    `-- src3
+  #   #      |-- dir0
+  #   #      |   |-- src0.txt
+  #   #      |   `-- src1.txt
+  #   #      `-- dir1
+  #   #          |-- src2.txt
+  #   #          `-- src3.txt
+  #
+  # If +src+ is an array of paths and +dest+ is a directory,
+  # recursively copies from each path in +src+ to +dest+;
+  # the paths in +src+ may point to files and/or directories.
+  #
+  # Keyword arguments:
+  #
+  # - <tt>dereference_root: false</tt> - if +src+ is a symbolic link,
+  #   does not dereference it.
+  # - <tt>noop: true</tt> - does not copy files.
+  # - <tt>preserve: true</tt> - preserves file times.
+  # - <tt>remove_destination: true</tt> - removes +dest+ before copying files.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     FileUtils.cp_r('src0.txt', 'dest0.txt', noop: true, verbose: true)
+  #     FileUtils.cp_r('src1.txt', 'dest1', noop: true, verbose: true)
+  #     FileUtils.cp_r('src2', 'dest2', noop: true, verbose: true)
+  #     FileUtils.cp_r('src3', 'dest3', noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     cp -r src0.txt dest0.txt
+  #     cp -r src1.txt dest1
+  #     cp -r src2 dest2
+  #     cp -r src3 dest3
+  #
+  # Raises an exception of +src+ is the path to a directory
+  # and +dest+ is the path to a file.
+  #
+  # Related: {methods for copying}[rdoc-ref:FileUtils@Copying].
   #
   def cp_r(src, dest, preserve: nil, noop: nil, verbose: nil,
            dereference_root: true, remove_destination: nil)
@@ -463,21 +1002,50 @@ module FileUtils
   end
   module_function :cp_r
 
+  # Recursively copies files from +src+ to +dest+.
+  #
+  # Arguments +src+ and +dest+
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # If +src+ is the path to a file, copies +src+ to +dest+:
+  #
+  #   FileUtils.touch('src0.txt')
+  #   File.exist?('dest0.txt') # => false
+  #   FileUtils.copy_entry('src0.txt', 'dest0.txt')
+  #   File.file?('dest0.txt')  # => true
   #
-  # Copies a file system entry +src+ to +dest+.
-  # If +src+ is a directory, this method copies its contents recursively.
-  # This method preserves file types, c.f. symlink, directory...
-  # (FIFO, device files and etc. are not supported yet)
+  # If +src+ is a directory, recursively copies +src+ to +dest+:
   #
-  # Both of +src+ and +dest+ must be a path name.
-  # +src+ must exist, +dest+ must not exist.
+  #   tree('src1')
+  #   # => src1
+  #   #    |-- dir0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- dir1
+  #   #        |-- src2.txt
+  #   #        `-- src3.txt
+  #   FileUtils.copy_entry('src1', 'dest1')
+  #   tree('dest1')
+  #   # => dest1
+  #   #    |-- dir0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- dir1
+  #   #        |-- src2.txt
+  #   #        `-- src3.txt
   #
-  # If +preserve+ is true, this method preserves owner, group, and
-  # modified time.  Permissions are copied regardless +preserve+.
+  # The recursive copying preserves file types for regular files,
+  # directories, and symbolic links;
+  # other file types (FIFO streams, device files, etc.) are not supported.
   #
-  # If +dereference_root+ is true, this method dereference tree root.
+  # Keyword arguments:
   #
-  # If +remove_destination+ is true, this method removes each destination file before copy.
+  # - <tt>dereference_root: true</tt> - if +src+ is a symbolic link,
+  #   follows the link.
+  # - <tt>preserve: true</tt> - preserves file times.
+  # - <tt>remove_destination: true</tt> - removes +dest+ before copying files.
+  #
+  # Related: {methods for copying}[rdoc-ref:FileUtils@Copying].
   #
   def copy_entry(src, dest, preserve = false, dereference_root = false, remove_destination = false)
     if dereference_root
@@ -495,9 +1063,25 @@ module FileUtils
   end
   module_function :copy_entry
 
+  # Copies file from +src+ to +dest+, which should not be directories.
+  #
+  # Arguments +src+ and +dest+
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # Examples:
+  #
+  #   FileUtils.touch('src0.txt')
+  #   FileUtils.copy_file('src0.txt', 'dest0.txt')
+  #   File.file?('dest0.txt') # => true
   #
-  # Copies file contents of +src+ to +dest+.
-  # Both of +src+ and +dest+ must be a path name.
+  # Keyword arguments:
+  #
+  # - <tt>dereference: false</tt> - if +src+ is a symbolic link,
+  #   does not follow the link.
+  # - <tt>preserve: true</tt> - preserves file times.
+  # - <tt>remove_destination: true</tt> - removes +dest+ before copying files.
+  #
+  # Related: {methods for copying}[rdoc-ref:FileUtils@Copying].
   #
   def copy_file(src, dest, preserve = false, dereference = true)
     ent = Entry_.new(src, nil, dereference)
@@ -506,25 +1090,81 @@ module FileUtils
   end
   module_function :copy_file
 
+  # Copies \IO stream +src+ to \IO stream +dest+ via
+  # {IO.copy_stream}[rdoc-ref:IO.copy_stream].
   #
-  # Copies stream +src+ to +dest+.
-  # +src+ must respond to #read(n) and
-  # +dest+ must respond to #write(str).
+  # Related: {methods for copying}[rdoc-ref:FileUtils@Copying].
   #
   def copy_stream(src, dest)
     IO.copy_stream(src, dest)
   end
   module_function :copy_stream
 
-  #
-  # Moves file(s) +src+ to +dest+.  If +file+ and +dest+ exist on the different
-  # disk partition, the file is copied then the original file is removed.
-  #
-  #   FileUtils.mv 'badname.rb', 'goodname.rb'
-  #   FileUtils.mv 'stuff.rb', '/notexist/lib/ruby', force: true  # no error
-  #
-  #   FileUtils.mv %w(junk.txt dust.txt), '/home/foo/.trash/'
-  #   FileUtils.mv Dir.glob('test*.rb'), 'test', noop: true, verbose: true
+  # Moves entries.
+  #
+  # Arguments +src+ (a single path or an array of paths)
+  # and +dest+ (a single path)
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # If +src+ and +dest+ are on different file systems,
+  # first copies, then removes +src+.
+  #
+  # May cause a local vulnerability if not called with keyword argument
+  # <tt>secure: true</tt>;
+  # see {Avoiding the TOCTTOU Vulnerability}[rdoc-ref:FileUtils@Avoiding+the+TOCTTOU+Vulnerability].
+  #
+  # If +src+ is the path to a single file or directory and +dest+ does not exist,
+  # moves +src+ to +dest+:
+  #
+  #   tree('src0')
+  #   # => src0
+  #   #    |-- src0.txt
+  #   #    `-- src1.txt
+  #   File.exist?('dest0') # => false
+  #   FileUtils.mv('src0', 'dest0')
+  #   File.exist?('src0')  # => false
+  #   tree('dest0')
+  #   # => dest0
+  #   #    |-- src0.txt
+  #   #    `-- src1.txt
+  #
+  # If +src+ is an array of paths to files and directories
+  # and +dest+ is the path to a directory,
+  # copies from each path in the array to +dest+:
+  #
+  #   File.file?('src1.txt') # => true
+  #   tree('src1')
+  #   # => src1
+  #   #    |-- src.dat
+  #   #    `-- src.txt
+  #   Dir.empty?('dest1')    # => true
+  #   FileUtils.mv(['src1.txt', 'src1'], 'dest1')
+  #   tree('dest1')
+  #   # => dest1
+  #   #    |-- src1
+  #   #    |   |-- src.dat
+  #   #    |   `-- src.txt
+  #   #    `-- src1.txt
+  #
+  # Keyword arguments:
+  #
+  # - <tt>force: true</tt> - if the move includes removing +src+
+  #   (that is, if +src+ and +dest+ are on different file systems),
+  #   ignores raised exceptions of StandardError and its descendants.
+  # - <tt>noop: true</tt> - does not move files.
+  # - <tt>secure: true</tt> - removes +src+ securely;
+  #   see details at FileUtils.remove_entry_secure.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     FileUtils.mv('src0', 'dest0', noop: true, verbose: true)
+  #     FileUtils.mv(['src1.txt', 'src1'], 'dest1', noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     mv src0 dest0
+  #     mv src1.txt src1 dest1
+  #
+  # FileUtils.move is an alias for FileUtils.mv.
   #
   def mv(src, dest, force: nil, noop: nil, verbose: nil, secure: nil)
     fu_output_message "mv#{force ? ' -f' : ''} #{[src,dest].flatten.join ' '}" if verbose
@@ -558,13 +1198,34 @@ module FileUtils
   alias move mv
   module_function :move
 
+  # Removes entries at the paths in the given +list+
+  # (a single path or an array of paths)
+  # returns +list+, if it is an array, <tt>[list]</tt> otherwise.
+  #
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # With no keyword arguments, removes files at the paths given in +list+:
+  #
+  #   FileUtils.touch(['src0.txt', 'src0.dat'])
+  #   FileUtils.rm(['src0.dat', 'src0.txt']) # => ["src0.dat", "src0.txt"]
   #
-  # Remove file(s) specified in +list+.  This method cannot remove directories.
-  # All StandardErrors are ignored when the :force option is set.
+  # Keyword arguments:
   #
-  #   FileUtils.rm %w( junk.txt dust.txt )
-  #   FileUtils.rm Dir.glob('*.so')
-  #   FileUtils.rm 'NotExistFile', force: true   # never raises exception
+  # - <tt>force: true</tt> - ignores raised exceptions of StandardError
+  #   and its descendants.
+  # - <tt>noop: true</tt> - does not remove files; returns +nil+.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     FileUtils.rm(['src0.dat', 'src0.txt'], noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     rm src0.dat src0.txt
+  #
+  # FileUtils.remove is an alias for FileUtils.rm.
+  #
+  # Related: {methods for deleting}[rdoc-ref:FileUtils@Deleting].
   #
   def rm(list, force: nil, noop: nil, verbose: nil)
     list = fu_list(list)
@@ -580,10 +1241,18 @@ module FileUtils
   alias remove rm
   module_function :remove
 
+  # Equivalent to:
+  #
+  #   FileUtils.rm(list, force: true, **kwargs)
+  #
+  # Argument +list+ (a single path or an array of paths)
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # See FileUtils.rm for keyword arguments.
   #
-  # Equivalent to
+  # FileUtils.safe_unlink is an alias for FileUtils.rm_f.
   #
-  #   FileUtils.rm(list, force: true)
+  # Related: {methods for deleting}[rdoc-ref:FileUtils@Deleting].
   #
   def rm_f(list, noop: nil, verbose: nil)
     rm list, force: true, noop: noop, verbose: verbose
@@ -593,24 +1262,55 @@ module FileUtils
   alias safe_unlink rm_f
   module_function :safe_unlink
 
+  # Removes entries at the paths in the given +list+
+  # (a single path or an array of paths);
+  # returns +list+, if it is an array, <tt>[list]</tt> otherwise.
+  #
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # May cause a local vulnerability if not called with keyword argument
+  # <tt>secure: true</tt>;
+  # see {Avoiding the TOCTTOU Vulnerability}[rdoc-ref:FileUtils@Avoiding+the+TOCTTOU+Vulnerability].
+  #
+  # For each file path, removes the file at that path:
+  #
+  #   FileUtils.touch(['src0.txt', 'src0.dat'])
+  #   FileUtils.rm_r(['src0.dat', 'src0.txt'])
+  #   File.exist?('src0.txt') # => false
+  #   File.exist?('src0.dat') # => false
+  #
+  # For each directory path, recursively removes files and directories:
+  #
+  #   tree('src1')
+  #   # => src1
+  #   #    |-- dir0
+  #   #    |   |-- src0.txt
+  #   #    |   `-- src1.txt
+  #   #    `-- dir1
+  #   #        |-- src2.txt
+  #   #        `-- src3.txt
+  #   FileUtils.rm_r('src1')
+  #   File.exist?('src1') # => false
+  #
+  # Keyword arguments:
+  #
+  # - <tt>force: true</tt> - ignores raised exceptions of StandardError
+  #   and its descendants.
+  # - <tt>noop: true</tt> - does not remove entries; returns +nil+.
+  # - <tt>secure: true</tt> - removes +src+ securely;
+  #   see details at FileUtils.remove_entry_secure.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
   #
-  # remove files +list+[0] +list+[1]... If +list+[n] is a directory,
-  # removes its all contents recursively. This method ignores
-  # StandardError when :force option is set.
+  #     FileUtils.rm_r(['src0.dat', 'src0.txt'], noop: true, verbose: true)
+  #     FileUtils.rm_r('src1', noop: true, verbose: true)
   #
-  #   FileUtils.rm_r Dir.glob('/tmp/*')
-  #   FileUtils.rm_r 'some_dir', force: true
+  #   Output:
   #
-  # WARNING: This method causes local vulnerability
-  # if one of parent directories or removing directory tree are world
-  # writable (including /tmp, whose permission is 1777), and the current
-  # process has strong privilege such as Unix super user (root), and the
-  # system has symbolic link.  For secure removing, read the documentation
-  # of remove_entry_secure carefully, and set :secure option to true.
-  # Default is <tt>secure: false</tt>.
+  #     rm -r src0.dat src0.txt
+  #     rm -r src1
   #
-  # NOTE: This method calls remove_entry_secure if :secure option is set.
-  # See also remove_entry_secure.
+  # Related: {methods for deleting}[rdoc-ref:FileUtils@Deleting].
   #
   def rm_r(list, force: nil, noop: nil, verbose: nil, secure: nil)
     list = fu_list(list)
@@ -626,13 +1326,22 @@ module FileUtils
   end
   module_function :rm_r
 
+  # Equivalent to:
   #
-  # Equivalent to
+  #   FileUtils.rm_r(list, force: true, **kwargs)
   #
-  #   FileUtils.rm_r(list, force: true)
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
   #
-  # WARNING: This method causes local vulnerability.
-  # Read the documentation of rm_r first.
+  # May cause a local vulnerability if not called with keyword argument
+  # <tt>secure: true</tt>;
+  # see {Avoiding the TOCTTOU Vulnerability}[rdoc-ref:FileUtils@Avoiding+the+TOCTTOU+Vulnerability].
+  #
+  # See FileUtils.rm_r for keyword arguments.
+  #
+  # FileUtils.rmtree is an alias for FileUtils.rm_rf.
+  #
+  # Related: {methods for deleting}[rdoc-ref:FileUtils@Deleting].
   #
   def rm_rf(list, noop: nil, verbose: nil, secure: nil)
     rm_r list, force: true, noop: noop, verbose: verbose, secure: secure
@@ -642,37 +1351,20 @@ module FileUtils
   alias rmtree rm_rf
   module_function :rmtree
 
+  # Securely removes the entry given by +path+,
+  # which should be the entry for a regular file, a symbolic link,
+  # or a directory.
   #
-  # This method removes a file system entry +path+.  +path+ shall be a
-  # regular file, a directory, or something.  If +path+ is a directory,
-  # remove it recursively.  This method is required to avoid TOCTTOU
-  # (time-of-check-to-time-of-use) local security vulnerability of rm_r.
-  # #rm_r causes security hole when:
-  #
-  # * Parent directory is world writable (including /tmp).
-  # * Removing directory tree includes world writable directory.
-  # * The system has symbolic link.
-  #
-  # To avoid this security hole, this method applies special preprocess.
-  # If +path+ is a directory, this method chown(2) and chmod(2) all
-  # removing directories.  This requires the current process is the
-  # owner of the removing whole directory tree, or is the super user (root).
+  # Argument +path+
+  # should be {interpretable as a path}[rdoc-ref:FileUtils@Path+Arguments].
   #
-  # WARNING: You must ensure that *ALL* parent directories cannot be
-  # moved by other untrusted users.  For example, parent directories
-  # should not be owned by untrusted users, and should not be world
-  # writable except when the sticky bit set.
+  # Avoids a local vulnerability that can exist in certain circumstances;
+  # see {Avoiding the TOCTTOU Vulnerability}[rdoc-ref:FileUtils@Avoiding+the+TOCTTOU+Vulnerability].
   #
-  # WARNING: Only the owner of the removing directory tree, or Unix super
-  # user (root) should invoke this method.  Otherwise this method does not
-  # work.
+  # Optional argument +force+ specifies whether to ignore
+  # raised exceptions of StandardError and its descendants.
   #
-  # For details of this security vulnerability, see Perl's case:
-  #
-  # * https://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2005-0448
-  # * https://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2004-0452
-  #
-  # For fileutils.rb, this vulnerability is reported in [ruby-dev:26100].
+  # Related: {methods for deleting}[rdoc-ref:FileUtils@Deleting].
   #
   def remove_entry_secure(path, force = false)
     unless fu_have_symlink?
@@ -760,12 +1452,17 @@ module FileUtils
   end
   private_module_function :fu_stat_identical_entry?
 
+  # Removes the entry given by +path+,
+  # which should be the entry for a regular file, a symbolic link,
+  # or a directory.
   #
-  # This method removes a file system entry +path+.
-  # +path+ might be a regular file, a directory, or something.
-  # If +path+ is a directory, remove it recursively.
+  # Argument +path+
+  # should be {interpretable as a path}[rdoc-ref:FileUtils@Path+Arguments].
   #
-  # See also remove_entry_secure.
+  # Optional argument +force+ specifies whether to ignore
+  # raised exceptions of StandardError and its descendants.
+  #
+  # Related: FileUtils.remove_entry_secure.
   #
   def remove_entry(path, force = false)
     Entry_.new(path).postorder_traverse do |ent|
@@ -780,9 +1477,16 @@ module FileUtils
   end
   module_function :remove_entry
 
+  # Removes the file entry given by +path+,
+  # which should be the entry for a regular file or a symbolic link.
+  #
+  # Argument +path+
+  # should be {interpretable as a path}[rdoc-ref:FileUtils@Path+Arguments].
   #
-  # Removes a file +path+.
-  # This method ignores StandardError if +force+ is true.
+  # Optional argument +force+ specifies whether to ignore
+  # raised exceptions of StandardError and its descendants.
+  #
+  # Related: {methods for deleting}[rdoc-ref:FileUtils@Deleting].
   #
   def remove_file(path, force = false)
     Entry_.new(path).remove_file
@@ -791,20 +1495,32 @@ module FileUtils
   end
   module_function :remove_file
 
+  # Recursively removes the directory entry given by +path+,
+  # which should be the entry for a regular file, a symbolic link,
+  # or a directory.
+  #
+  # Argument +path+
+  # should be {interpretable as a path}[rdoc-ref:FileUtils@Path+Arguments].
   #
-  # Removes a directory +dir+ and its contents recursively.
-  # This method ignores StandardError if +force+ is true.
+  # Optional argument +force+ specifies whether to ignore
+  # raised exceptions of StandardError and its descendants.
+  #
+  # Related: {methods for deleting}[rdoc-ref:FileUtils@Deleting].
   #
   def remove_dir(path, force = false)
     remove_entry path, force   # FIXME?? check if it is a directory
   end
   module_function :remove_dir
 
+  # Returns +true+ if the contents of files +a+ and +b+ are identical,
+  # +false+ otherwise.
+  #
+  # Arguments +a+ and +b+
+  # should be {interpretable as a path}[rdoc-ref:FileUtils@Path+Arguments].
   #
-  # Returns true if the contents of a file +a+ and a file +b+ are identical.
+  # FileUtils.identical? and FileUtils.cmp are aliases for FileUtils.compare_file.
   #
-  #   FileUtils.compare_file('somefile', 'somefile')       #=> true
-  #   FileUtils.compare_file('/dev/null', '/dev/urandom')  #=> false
+  # Related: FileUtils.compare_stream.
   #
   def compare_file(a, b)
     return false unless File.size(a) == File.size(b)
@@ -821,8 +1537,13 @@ module FileUtils
   module_function :identical?
   module_function :cmp
 
+  # Returns +true+ if the contents of streams +a+ and +b+ are identical,
+  # +false+ otherwise.
   #
-  # Returns true if the contents of a stream +a+ and +b+ are identical.
+  # Arguments +a+ and +b+
+  # should be {interpretable as a path}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # Related: FileUtils.compare_file.
   #
   def compare_stream(a, b)
     bsize = fu_stream_blksize(a, b)
@@ -839,13 +1560,69 @@ module FileUtils
   end
   module_function :compare_stream
 
+  # Copies a file entry.
+  # See {install(1)}[https://man7.org/linux/man-pages/man1/install.1.html].
+  #
+  # Arguments +src+ (a single path or an array of paths)
+  # and +dest+ (a single path)
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments];
+  #
+  # If the entry at +dest+ does not exist, copies from +src+ to +dest+:
+  #
+  #   File.read('src0.txt')    # => "aaa\n"
+  #   File.exist?('dest0.txt') # => false
+  #   FileUtils.install('src0.txt', 'dest0.txt')
+  #   File.read('dest0.txt')   # => "aaa\n"
   #
-  # If +src+ is not same as +dest+, copies it and changes the permission
-  # mode to +mode+.  If +dest+ is a directory, destination is +dest+/+src+.
-  # This method removes destination before copy.
+  # If +dest+ is a file entry, copies from +src+ to +dest+, overwriting:
   #
-  #   FileUtils.install 'ruby', '/usr/local/bin/ruby', mode: 0755, verbose: true
-  #   FileUtils.install 'lib.rb', '/usr/local/lib/ruby/site_ruby', verbose: true
+  #   File.read('src1.txt')  # => "aaa\n"
+  #   File.read('dest1.txt') # => "bbb\n"
+  #   FileUtils.install('src1.txt', 'dest1.txt')
+  #   File.read('dest1.txt') # => "aaa\n"
+  #
+  # If +dest+ is a directory entry, copies from +src+ to <tt>dest/src</tt>,
+  # overwriting if necessary:
+  #
+  #   File.read('src2.txt')       # => "aaa\n"
+  #   File.read('dest2/src2.txt') # => "bbb\n"
+  #   FileUtils.install('src2.txt', 'dest2')
+  #   File.read('dest2/src2.txt') # => "aaa\n"
+  #
+  # If +src+ is an array of paths and +dest+ points to a directory,
+  # copies each path +path+ in +src+ to <tt>dest/path</tt>:
+  #
+  #   File.file?('src3.txt') # => true
+  #   File.file?('src3.dat') # => true
+  #   FileUtils.mkdir('dest3')
+  #   FileUtils.install(['src3.txt', 'src3.dat'], 'dest3')
+  #   File.file?('dest3/src3.txt') # => true
+  #   File.file?('dest3/src3.dat') # => true
+  #
+  # Keyword arguments:
+  #
+  # - <tt>group: <i>group</i></tt> - changes the group if not +nil+,
+  #   using {File.chown}[rdoc-ref:File.chown].
+  # - <tt>mode: <i>permissions</i></tt> - changes the permissions.
+  #   using {File.chmod}[rdoc-ref:File.chmod].
+  # - <tt>noop: true</tt> - does not copy entries; returns +nil+.
+  # - <tt>owner: <i>owner</i></tt> - changes the owner if not +nil+,
+  #   using {File.chown}[rdoc-ref:File.chown].
+  # - <tt>preserve: true</tt> - preserve timestamps
+  #   using {File.utime}[rdoc-ref:File.utime].
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     FileUtils.install('src0.txt', 'dest0.txt', noop: true, verbose: true)
+  #     FileUtils.install('src1.txt', 'dest1.txt', noop: true, verbose: true)
+  #     FileUtils.install('src2.txt', 'dest2', noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     install -c src0.txt dest0.txt
+  #     install -c src1.txt dest1.txt
+  #     install -c src2.txt dest2
+  #
+  # Related: {methods for copying}[rdoc-ref:FileUtils@Copying].
   #
   def install(src, dest, mode: nil, owner: nil, group: nil, preserve: nil,
               noop: nil, verbose: nil)
@@ -963,37 +1740,78 @@ module FileUtils
   end
   private_module_function :mode_to_s
 
+  # Changes permissions on the entries at the paths given in +list+
+  # (a single path or an array of paths)
+  # to the permissions given by +mode+;
+  # returns +list+ if it is an array, <tt>[list]</tt> otherwise:
+  #
+  # - Modifies each entry that is a regular file using
+  #   {File.chmod}[rdoc-ref:File.chmod].
+  # - Modifies each entry that is a symbolic link using
+  #   {File.lchmod}[rdoc-ref:File.lchmod].
+  #
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # Argument +mode+ may be either an integer or a string:
+  #
+  # - \Integer +mode+: represents the permission bits to be set:
+  #
+  #     FileUtils.chmod(0755, 'src0.txt')
+  #     FileUtils.chmod(0644, ['src0.txt', 'src0.dat'])
+  #
+  # - \String +mode+: represents the permissions to be set:
+  #
+  #   The string is of the form <tt>[targets][[operator][perms[,perms]]</tt>, where:
+  #
+  #   - +targets+ may be any combination of these letters:
+  #
+  #     - <tt>'u'</tt>: permissions apply to the file's owner.
+  #     - <tt>'g'</tt>: permissions apply to users in the file's group.
+  #     - <tt>'o'</tt>: permissions apply to other users not in the file's group.
+  #     - <tt>'a'</tt> (the default): permissions apply to all users.
+  #
+  #   - +operator+ may be one of these letters:
+  #
+  #     - <tt>'+'</tt>: adds permissions.
+  #     - <tt>'-'</tt>: removes permissions.
+  #     - <tt>'='</tt>: sets (replaces) permissions.
+  #
+  #   - +perms+ (may be repeated, with separating commas)
+  #     may be any combination of these letters:
+  #
+  #     - <tt>'r'</tt>: Read.
+  #     - <tt>'w'</tt>: Write.
+  #     - <tt>'x'</tt>: Execute (search, for a directory).
+  #     - <tt>'X'</tt>: Search (for a directories only;
+  #       must be used with <tt>'+'</tt>)
+  #     - <tt>'s'</tt>: Uid or gid.
+  #     - <tt>'t'</tt>: Sticky bit.
+  #
+  #   Examples:
+  #
+  #     FileUtils.chmod('u=wrx,go=rx', 'src1.txt')
+  #     FileUtils.chmod('u=wrx,go=rx', '/usr/bin/ruby')
+  #
+  # Keyword arguments:
+  #
+  # - <tt>noop: true</tt> - does not change permissions; returns +nil+.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     FileUtils.chmod(0755, 'src0.txt', noop: true, verbose: true)
+  #     FileUtils.chmod(0644, ['src0.txt', 'src0.dat'], noop: true, verbose: true)
+  #     FileUtils.chmod('u=wrx,go=rx', 'src1.txt', noop: true, verbose: true)
+  #     FileUtils.chmod('u=wrx,go=rx', '/usr/bin/ruby', noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     chmod 755 src0.txt
+  #     chmod 644 src0.txt src0.dat
+  #     chmod u=wrx,go=rx src1.txt
+  #     chmod u=wrx,go=rx /usr/bin/ruby
+  #
+  # Related: FileUtils.chmod_R.
   #
-  # Changes permission bits on the named files (in +list+) to the bit pattern
-  # represented by +mode+.
-  #
-  # +mode+ is the symbolic and absolute mode can be used.
-  #
-  # Absolute mode is
-  #   FileUtils.chmod 0755, 'somecommand'
-  #   FileUtils.chmod 0644, %w(my.rb your.rb his.rb her.rb)
-  #   FileUtils.chmod 0755, '/usr/bin/ruby', verbose: true
-  #
-  # Symbolic mode is
-  #   FileUtils.chmod "u=wrx,go=rx", 'somecommand'
-  #   FileUtils.chmod "u=wr,go=rr", %w(my.rb your.rb his.rb her.rb)
-  #   FileUtils.chmod "u=wrx,go=rx", '/usr/bin/ruby', verbose: true
-  #
-  # "a" :: is user, group, other mask.
-  # "u" :: is user's mask.
-  # "g" :: is group's mask.
-  # "o" :: is other's mask.
-  # "w" :: is write permission.
-  # "r" :: is read permission.
-  # "x" :: is execute permission.
-  # "X" ::
-  #   is execute permission for directories only, must be used in conjunction with "+"
-  # "s" :: is uid, gid.
-  # "t" :: is sticky bit.
-  # "+" :: is added to a class given the specified mode.
-  # "-" :: Is removed from a given class given mode.
-  # "=" :: Is the exact nature of the class will be given a specified mode.
-
   def chmod(mode, list, noop: nil, verbose: nil)
     list = fu_list(list)
     fu_output_message sprintf('chmod %s %s', mode_to_s(mode), list.join(' ')) if verbose
@@ -1004,12 +1822,7 @@ module FileUtils
   end
   module_function :chmod
 
-  #
-  # Changes permission bits on the named files (in +list+)
-  # to the bit pattern represented by +mode+.
-  #
-  #   FileUtils.chmod_R 0700, "/tmp/app.#{$$}"
-  #   FileUtils.chmod_R "u=wrx", "/tmp/app.#{$$}"
+  # Like FileUtils.chmod, but changes permissions recursively.
   #
   def chmod_R(mode, list, noop: nil, verbose: nil, force: nil)
     list = fu_list(list)
@@ -1029,15 +1842,68 @@ module FileUtils
   end
   module_function :chmod_R
 
+  # Changes the owner and group on the entries at the paths given in +list+
+  # (a single path or an array of paths)
+  # to the given +user+ and +group+;
+  # returns +list+ if it is an array, <tt>[list]</tt> otherwise:
+  #
+  # - Modifies each entry that is a regular file using
+  #   {File.chown}[rdoc-ref:File.chown].
+  # - Modifies each entry that is a symbolic link using
+  #   {File.lchown}[rdoc-ref:File.lchown].
+  #
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # User and group:
+  #
+  # - Argument +user+ may be a user name or a user id;
+  #   if +nil+ or +-1+, the user is not changed.
+  # - Argument +group+ may be a group name or a group id;
+  #   if +nil+ or +-1+, the group is not changed.
+  # - The user must be a member of the group.
+  #
+  # Examples:
+  #
+  #   # One path.
+  #   # User and group as string names.
+  #   File.stat('src0.txt').uid # => 1004
+  #   File.stat('src0.txt').gid # => 1004
+  #   FileUtils.chown('user2', 'group1', 'src0.txt')
+  #   File.stat('src0.txt').uid # => 1006
+  #   File.stat('src0.txt').gid # => 1005
+  #
+  #   # User and group as uid and gid.
+  #   FileUtils.chown(1004, 1004, 'src0.txt')
+  #   File.stat('src0.txt').uid # => 1004
+  #   File.stat('src0.txt').gid # => 1004
   #
-  # Changes owner and group on the named files (in +list+)
-  # to the user +user+ and the group +group+.  +user+ and +group+
-  # may be an ID (Integer/String) or a name (String).
-  # If +user+ or +group+ is nil, this method does not change
-  # the attribute.
+  #   # Array of paths.
+  #   FileUtils.chown(1006, 1005, ['src0.txt', 'src0.dat'])
   #
-  #   FileUtils.chown 'root', 'staff', '/usr/local/bin/ruby'
-  #   FileUtils.chown nil, 'bin', Dir.glob('/usr/bin/*'), verbose: true
+  #   # Directory (not recursive).
+  #   FileUtils.chown('user2', 'group1', '.')
+  #
+  # Keyword arguments:
+  #
+  # - <tt>noop: true</tt> - does not change permissions; returns +nil+.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     FileUtils.chown('user2', 'group1', 'src0.txt', noop: true, verbose: true)
+  #     FileUtils.chown(1004, 1004, 'src0.txt', noop: true, verbose: true)
+  #     FileUtils.chown(1006, 1005, ['src0.txt', 'src0.dat'], noop: true, verbose: true)
+  #     FileUtils.chown('user2', 'group1', path, noop: true, verbose: true)
+  #     FileUtils.chown('user2', 'group1', '.', noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     chown user2:group1 src0.txt
+  #     chown 1004:1004 src0.txt
+  #     chown 1006:1005 src0.txt src0.dat
+  #     chown user2:group1 src0.txt
+  #     chown user2:group1 .
+  #
+  # Related: FileUtils.chown_R.
   #
   def chown(user, group, list, noop: nil, verbose: nil)
     list = fu_list(list)
@@ -1053,15 +1919,7 @@ module FileUtils
   end
   module_function :chown
 
-  #
-  # Changes owner and group on the named files (in +list+)
-  # to the user +user+ and the group +group+ recursively.
-  # +user+ and +group+ may be an ID (Integer/String) or
-  # a name (String).  If +user+ or +group+ is nil, this
-  # method does not change the attribute.
-  #
-  #   FileUtils.chown_R 'www', 'www', '/var/www/htdocs'
-  #   FileUtils.chown_R 'cvs', 'cvs', '/var/cvs', verbose: true
+  # Like FileUtils.chown, but changes owner and group recursively.
   #
   def chown_R(user, group, list, noop: nil, verbose: nil, force: nil)
     list = fu_list(list)
@@ -1112,12 +1970,50 @@ module FileUtils
   end
   private_module_function :fu_get_gid
 
+  # Updates modification times (mtime) and access times (atime)
+  # of the entries given by the paths in +list+
+  # (a single path or an array of paths);
+  # returns +list+ if it is an array, <tt>[list]</tt> otherwise.
   #
-  # Updates modification time (mtime) and access time (atime) of file(s) in
-  # +list+.  Files are created if they don't exist.
+  # By default, creates an empty file for any path to a non-existent entry;
+  # use keyword argument +nocreate+ to raise an exception instead.
   #
-  #   FileUtils.touch 'timestamp'
-  #   FileUtils.touch Dir.glob('*.c');  system 'make'
+  # Argument +list+ or its elements
+  # should be {interpretable as paths}[rdoc-ref:FileUtils@Path+Arguments].
+  #
+  # Examples:
+  #
+  #   # Single path.
+  #   f = File.new('src0.txt') # Existing file.
+  #   f.atime # => 2022-06-10 11:11:21.200277 -0700
+  #   f.mtime # => 2022-06-10 11:11:21.200277 -0700
+  #   FileUtils.touch('src0.txt')
+  #   f = File.new('src0.txt')
+  #   f.atime # => 2022-06-11 08:28:09.8185343 -0700
+  #   f.mtime # => 2022-06-11 08:28:09.8185343 -0700
+  #
+  #   # Array of paths.
+  #   FileUtils.touch(['src0.txt', 'src0.dat'])
+  #
+  # Keyword arguments:
+  #
+  # - <tt>mtime: <i>time</i></tt> - sets the entry's mtime to the given time,
+  #   instead of the current time.
+  # - <tt>nocreate: true</tt> - raises an exception if the entry does not exist.
+  # - <tt>noop: true</tt> - does not touch entries; returns +nil+.
+  # - <tt>verbose: true</tt> - prints an equivalent command:
+  #
+  #     FileUtils.touch('src0.txt', noop: true, verbose: true)
+  #     FileUtils.touch(['src0.txt', 'src0.dat'], noop: true, verbose: true)
+  #     FileUtils.touch(path, noop: true, verbose: true)
+  #
+  #   Output:
+  #
+  #     touch src0.txt
+  #     touch src0.txt src0.dat
+  #     touch src0.txt
+  #
+  # Related: FileUtils.uptodate?.
   #
   def touch(list, noop: nil, verbose: nil, mtime: nil, nocreate: nil)
     list = fu_list(list)
@@ -1479,13 +2375,21 @@ module FileUtils
 
     def postorder_traverse
       if directory?
-        entries().each do |ent|
+        begin
+          children = entries()
+        rescue Errno::EACCES
+          # Failed to get the list of children.
+          # Assuming there is no children, try to process the parent directory.
+          yield self
+          return
+        end
+
+        children.each do |ent|
           ent.postorder_traverse do |e|
             yield e
           end
         end
       end
-    ensure
       yield self
     end
 
@@ -1579,15 +2483,15 @@ module FileUtils
   end
   private_module_function :fu_each_src_dest
 
-  def fu_each_src_dest0(src, dest)   #:nodoc:
+  def fu_each_src_dest0(src, dest, target_directory = true)   #:nodoc:
     if tmp = Array.try_convert(src)
       tmp.each do |s|
         s = File.path(s)
-        yield s, File.join(dest, File.basename(s))
+        yield s, (target_directory ? File.join(dest, File.basename(s)) : dest)
       end
     else
       src = File.path(src)
-      if File.directory?(dest)
+      if target_directory and File.directory?(dest)
         yield src, File.join(dest, File.basename(src))
       else
         yield src, File.path(dest)
@@ -1611,6 +2515,56 @@ module FileUtils
   end
   private_module_function :fu_output_message
 
+  def fu_split_path(path)
+    path = File.path(path)
+    list = []
+    until (parent, base = File.split(path); parent == path or parent == ".")
+      list << base
+      path = parent
+    end
+    list << path
+    list.reverse!
+  end
+  private_module_function :fu_split_path
+
+  def fu_relative_components_from(target, base) #:nodoc:
+    i = 0
+    while target[i]&.== base[i]
+      i += 1
+    end
+    Array.new(base.size-i, '..').concat(target[i..-1])
+  end
+  private_module_function :fu_relative_components_from
+
+  def fu_clean_components(*comp)
+    comp.shift while comp.first == "."
+    return comp if comp.empty?
+    clean = [comp.shift]
+    path = File.join(*clean, "") # ending with File::SEPARATOR
+    while c = comp.shift
+      if c == ".." and clean.last != ".." and !(fu_have_symlink? && File.symlink?(path))
+        clean.pop
+        path.chomp!(%r((?<=\A|/)[^/]+/\z), "")
+      else
+        clean << c
+        path << c << "/"
+      end
+    end
+    clean
+  end
+  private_module_function :fu_clean_components
+
+  if fu_windows?
+    def fu_starting_path?(path)
+      path&.start_with?(%r(\w:|/))
+    end
+  else
+    def fu_starting_path?(path)
+      path&.start_with?("/")
+    end
+  end
+  private_module_function :fu_starting_path?
+
   # This hash table holds command options.
   OPT_TABLE = {}    #:nodoc: internal use only
   (private_instance_methods & methods(false)).inject(OPT_TABLE) {|tbl, name|
@@ -1620,50 +2574,49 @@ module FileUtils
 
   public
 
+  # Returns an array of the string names of \FileUtils methods
+  # that accept one or more keyword arguments:
   #
-  # Returns an Array of names of high-level methods that accept any keyword
-  # arguments.
-  #
-  #   p FileUtils.commands  #=> ["chmod", "cp", "cp_r", "install", ...]
+  #   FileUtils.commands.sort.take(3) # => ["cd", "chdir", "chmod"]
   #
   def self.commands
     OPT_TABLE.keys
   end
 
+  # Returns an array of the string keyword names:
   #
-  # Returns an Array of option names.
-  #
-  #   p FileUtils.options  #=> ["noop", "force", "verbose", "preserve", "mode"]
+  #   FileUtils.options.take(3) # => ["noop", "verbose", "force"]
   #
   def self.options
     OPT_TABLE.values.flatten.uniq.map {|sym| sym.to_s }
   end
 
+  # Returns +true+ if method +mid+ accepts the given option +opt+, +false+ otherwise;
+  # the arguments may be strings or symbols:
   #
-  # Returns true if the method +mid+ have an option +opt+.
-  #
-  #   p FileUtils.have_option?(:cp, :noop)     #=> true
-  #   p FileUtils.have_option?(:rm, :force)    #=> true
-  #   p FileUtils.have_option?(:rm, :preserve) #=> false
+  #   FileUtils.have_option?(:chmod, :noop) # => true
+  #   FileUtils.have_option?('chmod', 'secure') # => false
   #
   def self.have_option?(mid, opt)
     li = OPT_TABLE[mid.to_s] or raise ArgumentError, "no such method: #{mid}"
     li.include?(opt)
   end
 
+  # Returns an array of the string keyword name for method +mid+;
+  # the argument may be a string or a symbol:
   #
-  # Returns an Array of option names of the method +mid+.
-  #
-  #   p FileUtils.options_of(:rm)  #=> ["noop", "verbose", "force"]
+  #   FileUtils.options_of(:rm) # => ["force", "noop", "verbose"]
+  #   FileUtils.options_of('mv') # => ["force", "noop", "verbose", "secure"]
   #
   def self.options_of(mid)
     OPT_TABLE[mid.to_s].map {|sym| sym.to_s }
   end
 
+  # Returns an array of the string method names of the methods
+  # that accept the given keyword option +opt+;
+  # the argument must be a symbol:
   #
-  # Returns an Array of methods names which have the option +opt+.
-  #
-  #   p FileUtils.collect_method(:preserve) #=> ["cp", "cp_r", "copy", "install"]
+  #   FileUtils.collect_method(:preserve) # => ["cp", "copy", "cp_r", "install"]
   #
   def self.collect_method(opt)
     OPT_TABLE.keys.select {|m| OPT_TABLE[m].include?(opt) }
diff --git a/lib/forwardable.rb b/lib/forwardable.rb
index c9c4128f9f..71b4e6adad 100644
--- a/lib/forwardable.rb
+++ b/lib/forwardable.rb
@@ -112,8 +112,10 @@ module Forwardable
   require 'forwardable/impl'
 
   # Version of +forwardable.rb+
-  VERSION = "1.3.2"
+  VERSION = "1.3.3"
+  VERSION.freeze
   FORWARDABLE_VERSION = VERSION
+  FORWARDABLE_VERSION.freeze
 
   @debug = nil
   class << self
diff --git a/lib/getoptlong.rb b/lib/getoptlong.rb
index d3fff34beb..5ae0e1497c 100644
--- a/lib/getoptlong.rb
+++ b/lib/getoptlong.rb
@@ -6,87 +6,369 @@
 #
 # You may redistribute and/or modify this library under the same license
 # terms as Ruby.
+
+# \Class \GetoptLong provides parsing both for options
+# and for regular arguments.
 #
-# See GetoptLong for documentation.
+# Using \GetoptLong, you can define options for your program.
+# The program can then capture and respond to whatever options
+# are included in the command that executes the program.
 #
-# Additional documents and the latest version of `getoptlong.rb' can be
-# found at http://www.sra.co.jp/people/m-kasahr/ruby/getoptlong/
-
-# The GetoptLong class allows you to parse command line options similarly to
-# the GNU getopt_long() C library call. Note, however, that GetoptLong is a
-# pure Ruby implementation.
+# A simple example: file <tt>simple.rb</tt>:
+#
+#   :include: ../sample/getoptlong/simple.rb
+#
+# If you are somewhat familiar with options,
+# you may want to skip to this
+# {full example}[#class-GetoptLong-label-Full+Example].
+#
+# == Options
+#
+# A \GetoptLong option has:
+#
+# - A string <em>option name</em>.
+# - Zero or more string <em>aliases</em> for the name.
+# - An <em>option type</em>.
+#
+# Options may be defined by calling singleton method GetoptLong.new,
+# which returns a new \GetoptLong object.
+# Options may then be processed by calling other methods
+# such as GetoptLong#each.
+#
+# === Option Name and Aliases
+#
+# In the array that defines an option,
+# the first element is the string option name.
+# Often the name takes the 'long' form, beginning with two hyphens.
+#
+# The option name may have any number of aliases,
+# which are defined by additional string elements.
+#
+# The name and each alias must be of one of two forms:
+#
+# - Two hyphens, followed by one or more letters.
+# - One hyphen, followed by a single letter.
+#
+# File <tt>aliases.rb</tt>:
+#
+#   :include: ../sample/getoptlong/aliases.rb
+#
+# An option may be cited by its name,
+# or by any of its aliases;
+# the parsed option always reports the name, not an alias:
+#
+#   $ ruby aliases.rb -a -p --xxx --aaa -x
+#
+# Output:
+#
+#   ["--xxx", ""]
+#   ["--xxx", ""]
+#   ["--xxx", ""]
+#   ["--xxx", ""]
+#   ["--xxx", ""]
+#
+#
+# An option may also be cited by an abbreviation of its name or any alias,
+# as long as that abbreviation is unique among the options.
+#
+# File <tt>abbrev.rb</tt>:
+#
+#   :include: ../sample/getoptlong/abbrev.rb
+#
+# Command line:
+#
+#   $ ruby abbrev.rb --xxx --xx --xyz --xy
+#
+# Output:
+#
+#   ["--xxx", ""]
+#   ["--xxx", ""]
+#   ["--xyz", ""]
+#   ["--xyz", ""]
+#
+# This command line raises GetoptLong::AmbiguousOption:
+#
+#   $ ruby abbrev.rb --x
+#
+# === Repetition
+#
+# An option may be cited more than once:
+#
+#   $ ruby abbrev.rb --xxx --xyz --xxx --xyz
+#
+# Output:
+#
+#   ["--xxx", ""]
+#   ["--xyz", ""]
+#   ["--xxx", ""]
+#   ["--xyz", ""]
+#
+# === Treating Remaining Options as Arguments
+#
+# A option-like token that appears
+# anywhere after the token <tt>--</tt> is treated as an ordinary argument,
+# and is not processed as an option:
+#
+#   $ ruby abbrev.rb --xxx --xyz -- --xxx --xyz
+#
+# Output:
+#
+#   ["--xxx", ""]
+#   ["--xyz", ""]
+#
+# === Option Types
+#
+# Each option definition includes an option type,
+# which controls whether the option takes an argument.
+#
+# File <tt>types.rb</tt>:
+#
+#   :include: ../sample/getoptlong/types.rb
+#
+# Note that an option type has to do with the <em>option argument</em>
+# (whether it is required, optional, or forbidden),
+# not with whether the option itself is required.
+#
+# ==== Option with Required Argument
+#
+# An option of type <tt>GetoptLong::REQUIRED_ARGUMENT</tt>
+# must be followed by an argument, which is associated with that option:
+#
+#   $ ruby types.rb --xxx foo
+#
+# Output:
+#
+#   ["--xxx", "foo"]
+#
+# If the option is not last, its argument is whatever follows it
+# (even if the argument looks like another option):
+#
+#   $ ruby types.rb --xxx --yyy
+#
+# Output:
+#
+#   ["--xxx", "--yyy"]
+#
+# If the option is last, an exception is raised:
+#
+#   $ ruby types.rb
+#   # Raises GetoptLong::MissingArgument
+#
+# ==== Option with Optional Argument
+#
+# An option of type <tt>GetoptLong::OPTIONAL_ARGUMENT</tt>
+# may be followed by an argument, which if given is associated with that option.
+#
+# If the option is last, it does not have an argument:
+#
+#   $ ruby types.rb --yyy
+#
+# Output:
+#
+#   ["--yyy", ""]
+#
+# If the option is followed by another option, it does not have an argument:
+#
+#   $ ruby types.rb --yyy --zzz
+#
+# Output:
+#
+#   ["--yyy", ""]
+#   ["--zzz", ""]
+#
+# Otherwise the option is followed by its argument, which is associated
+# with that option:
+#
+#   $ ruby types.rb --yyy foo
+#
+# Output:
+#
+#   ["--yyy", "foo"]
+#
+# ==== Option with No Argument
+#
+# An option of type <tt>GetoptLong::NO_ARGUMENT</tt> takes no argument:
+#
+#   ruby types.rb --zzz foo
+#
+# Output:
+#
+#   ["--zzz", ""]
+#
+# === ARGV
+#
+# You can process options either with method #each and a block,
+# or with method #get.
+#
+# During processing, each found option is removed, along with its argument
+# if there is one.
+# After processing, each remaining element was neither an option
+# nor the argument for an option.
+#
+# File <tt>argv.rb</tt>:
+#
+#   :include: ../sample/getoptlong/argv.rb
+#
+# Command line:
 #
-# GetoptLong allows for POSIX-style options like <tt>--file</tt> as well
-# as single letter options like <tt>-f</tt>
+#   $ ruby argv.rb --xxx Foo --yyy Bar Baz --zzz Bat Bam
 #
-# The empty option <tt>--</tt> (two minus symbols) is used to end option
-# processing. This can be particularly important if options have optional
-# arguments.
+# Output:
 #
-# Here is a simple example of usage:
+#   Original ARGV: ["--xxx", "Foo", "--yyy", "Bar", "Baz", "--zzz", "Bat", "Bam"]
+#   ["--xxx", "Foo"]
+#   ["--yyy", "Bar"]
+#   ["--zzz", ""]
+#   Remaining ARGV: ["Baz", "Bat", "Bam"]
 #
-#     require 'getoptlong'
+# === Ordering
 #
-#     opts = GetoptLong.new(
-#       [ '--help', '-h', GetoptLong::NO_ARGUMENT ],
-#       [ '--repeat', '-n', GetoptLong::REQUIRED_ARGUMENT ],
-#       [ '--name', GetoptLong::OPTIONAL_ARGUMENT ]
-#     )
+# There are three settings that control the way the options
+# are interpreted:
 #
-#     dir = nil
-#     name = nil
-#     repetitions = 1
-#     opts.each do |opt, arg|
-#       case opt
-#         when '--help'
-#           puts <<-EOF
-#     hello [OPTION] ... DIR
+# - +PERMUTE+.
+# - +REQUIRE_ORDER+.
+# - +RETURN_IN_ORDER+.
 #
+# The initial setting for a new \GetoptLong object is +REQUIRE_ORDER+
+# if environment variable +POSIXLY_CORRECT+ is defined, +PERMUTE+ otherwise.
+#
+# ==== PERMUTE Ordering
+#
+# In the +PERMUTE+ ordering, options and other, non-option,
+# arguments may appear in any order and any mixture.
+#
+# File <tt>permute.rb</tt>:
+#
+#   :include: ../sample/getoptlong/permute.rb
+#
+# Command line:
+#
+#   $ ruby permute.rb Foo --zzz Bar --xxx Baz --yyy Bat Bam --xxx Bag Bah
+#
+# Output:
+#
+#   Original ARGV: ["Foo", "--zzz", "Bar", "--xxx", "Baz", "--yyy", "Bat", "Bam", "--xxx", "Bag", "Bah"]
+#   ["--zzz", ""]
+#   ["--xxx", "Baz"]
+#   ["--yyy", "Bat"]
+#   ["--xxx", "Bag"]
+#   Remaining ARGV: ["Foo", "Bar", "Bam", "Bah"]
+#
+# ==== REQUIRE_ORDER Ordering
+#
+# In the +REQUIRE_ORDER+ ordering, all options precede all non-options;
+# that is, each word after the first non-option word
+# is treated as a non-option word (even if it begins with a hyphen).
+#
+# File <tt>require_order.rb</tt>:
+#
+#   :include: ../sample/getoptlong/require_order.rb
+#
+# Command line:
+#
+#   $ ruby require_order.rb --xxx Foo Bar --xxx Baz --yyy Bat -zzz
+#
+# Output:
+#
+#   Original ARGV: ["--xxx", "Foo", "Bar", "--xxx", "Baz", "--yyy", "Bat", "-zzz"]
+#   ["--xxx", "Foo"]
+#   Remaining ARGV: ["Bar", "--xxx", "Baz", "--yyy", "Bat", "-zzz"]
+#
+# ==== RETURN_IN_ORDER Ordering
+#
+# In the +RETURN_IN_ORDER+ ordering, every word is treated as an option.
+# A word that begins with a hyphen (or two) is treated in the usual way;
+# a word +word+ that does not so begin is treated as an option
+# whose name is an empty string, and whose value is +word+.
+#
+# File <tt>return_in_order.rb</tt>:
+#
+#   :include: ../sample/getoptlong/return_in_order.rb
+#
+# Command line:
+#
+#   $ ruby return_in_order.rb Foo --xxx Bar Baz --zzz Bat Bam
+#
+# Output:
+#
+#   Original ARGV: ["Foo", "--xxx", "Bar", "Baz", "--zzz", "Bat", "Bam"]
+#   ["", "Foo"]
+#   ["--xxx", "Bar"]
+#   ["", "Baz"]
+#   ["--zzz", ""]
+#   ["", "Bat"]
+#   ["", "Bam"]
+#   Remaining ARGV: []
+#
+# === Full Example
+#
+# File <tt>fibonacci.rb</tt>:
+#
+#   :include: ../sample/getoptlong/fibonacci.rb
+#
+# Command line:
+#
+#   $ ruby fibonacci.rb
+#
+# Output:
+#
+#   Option --number is required.
+#   Usage:
+#
+#     -n n, --number n:
+#       Compute Fibonacci number for n.
+#     -v [boolean], --verbose [boolean]:
+#       Show intermediate results; default is 'false'.
+#     -h, --help:
+#       Show this help.
+#
+# Command line:
+#
+#   $ ruby fibonacci.rb --number
+#
+# Raises GetoptLong::MissingArgument:
+#
+#   fibonacci.rb: option `--number' requires an argument
+#
+# Command line:
+#
+#   $ ruby fibonacci.rb --number 6
+#
+# Output:
+#
+#   8
+#
+# Command line:
+#
+#   $ ruby fibonacci.rb --number 6 --verbose
+#
+# Output:
+#   1
+#   2
+#   3
+#   5
+#   8
+#
+# Command line:
+#
+# $ ruby fibonacci.rb --number 6 --verbose yes
+#
+# Output:
+#
+#   --verbose argument must be true or false
+#   Usage:
+#
+#     -n n, --number n:
+#       Compute Fibonacci number for n.
+#     -v [boolean], --verbose [boolean]:
+#       Show intermediate results; default is 'false'.
 #     -h, --help:
-#        show help
-#
-#     --repeat x, -n x:
-#        repeat x times
-#
-#     --name [name]:
-#        greet user by name, if name not supplied default is John
-#
-#     DIR: The directory in which to issue the greeting.
-#           EOF
-#         when '--repeat'
-#           repetitions = arg.to_i
-#         when '--name'
-#           if arg == ''
-#             name = 'John'
-#           else
-#             name = arg
-#           end
-#       end
-#     end
-#
-#     if ARGV.length != 1
-#       puts "Missing dir argument (try --help)"
-#       exit 0
-#     end
-#
-#     dir = ARGV.shift
-#
-#     Dir.chdir(dir)
-#     for i in (1..repetitions)
-#       print "Hello"
-#       if name
-#         print ", #{name}"
-#       end
-#       puts
-#     end
-#
-# Example command line:
-#
-#     hello -n 6 --name -- /tmp
+#       Show this help.
 #
 class GetoptLong
   # Version.
-  VERSION = "0.1.1"
+  VERSION = "0.2.0"
 
   #
   # Orderings.
@@ -114,20 +396,18 @@ class GetoptLong
   class InvalidOption    < Error; end
 
   #
-  # \Set up option processing.
-  #
-  # The options to support are passed to new() as an array of arrays.
-  # Each sub-array contains any number of String option names which carry
-  # the same meaning, and one of the following flags:
+  # Returns a new \GetoptLong object based on the given +arguments+.
+  # See {Options}[#class-GetoptLong-label-Options].
   #
-  # GetoptLong::NO_ARGUMENT :: Option does not take an argument.
+  # Example:
   #
-  # GetoptLong::REQUIRED_ARGUMENT :: Option always takes an argument.
+  #   :include: ../sample/getoptlong/simple.rb
   #
-  # GetoptLong::OPTIONAL_ARGUMENT :: Option may or may not take an argument.
+  # Raises an exception if:
   #
-  # The first option name is considered to be the preferred (canonical) name.
-  # Other than that, the elements of each sub-array can be in any order.
+  # - Any of +arguments+ is not an array.
+  # - Any option name or alias is not a string.
+  # - Any option type is invalid.
   #
   def initialize(*arguments)
     #
@@ -189,54 +469,22 @@ class GetoptLong
     end
   end
 
+  # Sets the ordering; see {Ordering}[#class-GetoptLong-label-Ordering];
+  # returns the new ordering.
   #
-  # \Set the handling of the ordering of options and arguments.
-  # A RuntimeError is raised if option processing has already started.
-  #
-  # The supplied value must be a member of GetoptLong::ORDERINGS. It alters
-  # the processing of options as follows:
-  #
-  # <b>REQUIRE_ORDER</b> :
-  #
-  # Options are required to occur before non-options.
-  #
-  # Processing of options ends as soon as a word is encountered that has not
-  # been preceded by an appropriate option flag.
-  #
-  # For example, if -a and -b are options which do not take arguments,
-  # parsing command line arguments of '-a one -b two' would result in
-  # 'one', '-b', 'two' being left in ARGV, and only ('-a', '') being
-  # processed as an option/arg pair.
-  #
-  # This is the default ordering, if the environment variable
-  # POSIXLY_CORRECT is set. (This is for compatibility with GNU getopt_long.)
-  #
-  # <b>PERMUTE</b> :
-  #
-  # Options can occur anywhere in the command line parsed. This is the
-  # default behavior.
-  #
-  # Every sequence of words which can be interpreted as an option (with or
-  # without argument) is treated as an option; non-option words are skipped.
-  #
-  # For example, if -a does not require an argument and -b optionally takes
-  # an argument, parsing '-a one -b two three' would result in ('-a','') and
-  # ('-b', 'two') being processed as option/arg pairs, and 'one','three'
-  # being left in ARGV.
+  # If the given +ordering+ is +PERMUTE+ and environment variable
+  # +POSIXLY_CORRECT+ is defined, sets the ordering to +REQUIRE_ORDER+;
+  # otherwise sets the ordering to +ordering+:
   #
-  # If the ordering is set to PERMUTE but the environment variable
-  # POSIXLY_CORRECT is set, REQUIRE_ORDER is used instead. This is for
-  # compatibility with GNU getopt_long.
+  #   options = GetoptLong.new
+  #   options.ordering == GetoptLong::PERMUTE # => true
+  #   options.ordering = GetoptLong::RETURN_IN_ORDER
+  #   options.ordering == GetoptLong::RETURN_IN_ORDER # => true
+  #   ENV['POSIXLY_CORRECT'] = 'true'
+  #   options.ordering = GetoptLong::PERMUTE
+  #   options.ordering == GetoptLong::REQUIRE_ORDER # => true
   #
-  # <b>RETURN_IN_ORDER</b> :
-  #
-  # All words on the command line are processed as options. Words not
-  # preceded by a short or long option flag are passed as arguments
-  # with an option of '' (empty string).
-  #
-  # For example, if -a requires an argument but -b does not, a command line
-  # of '-a one -b two three' would result in option/arg pairs of ('-a', 'one')
-  # ('-b', ''), ('', 'two'), ('', 'three') being processed.
+  # Raises an exception if +ordering+ is invalid.
   #
   def ordering=(ordering)
     #
@@ -262,14 +510,16 @@ class GetoptLong
   end
 
   #
-  # Return ordering.
+  # Returns the ordering setting.
   #
   attr_reader :ordering
 
   #
-  # \Set options. Takes the same argument as GetoptLong.new.
+  # Replaces existing options with those given by +arguments+,
+  # which have the same form as the arguments to ::new;
+  # returns +self+.
   #
-  # Raises a RuntimeError if option processing has already started.
+  # Raises an exception if option processing has begun.
   #
   def set_options(*arguments)
     #
@@ -341,22 +591,23 @@ class GetoptLong
   end
 
   #
-  # \Set/Unset `quiet' mode.
+  # Sets quiet mode and returns the given argument:
+  #
+  # - When +false+ or +nil+, error messages are written to <tt>$stdout</tt>.
+  # - Otherwise, error messages are not written.
   #
   attr_writer :quiet
 
   #
-  # Return the flag of `quiet' mode.
+  # Returns the quiet mode setting.
   #
   attr_reader :quiet
-
-  #
-  # `quiet?' is an alias of `quiet'.
-  #
   alias quiet? quiet
 
   #
-  # Explicitly terminate option processing.
+  # Terminate option processing;
+  # returns +nil+ if processing has already terminated;
+  # otherwise returns +self+.
   #
   def terminate
     return nil if @status == STATUS_TERMINATED
@@ -376,7 +627,7 @@ class GetoptLong
   end
 
   #
-  # Returns true if option processing has terminated, false otherwise.
+  # Returns +true+ if option processing has terminated, +false+ otherwise.
   #
   def terminated?
     return @status == STATUS_TERMINATED
@@ -400,32 +651,25 @@ class GetoptLong
   protected :set_error
 
   #
-  # Examine whether an option processing is failed.
+  # Returns whether option processing has failed.
   #
   attr_reader :error
-
-  #
-  # `error?' is an alias of `error'.
-  #
   alias error? error
 
   # Return the appropriate error message in POSIX-defined format.
-  # If no error has occurred, returns nil.
+  # If no error has occurred, returns +nil+.
   #
   def error_message
     return @error_message
   end
 
   #
-  # Get next option name and its argument, as an Array of two elements.
-  #
-  # The option name is always converted to the first (preferred)
-  # name given in the original options to GetoptLong.new.
+  # Returns the next option as a 2-element array containing:
   #
-  # Example: ['--option', 'value']
+  # - The option name (the name itself, not an alias).
+  # - The option value.
   #
-  # Returns nil if the processing is complete (as determined by
-  # STATUS_TERMINATED).
+  # Returns +nil+ if there are no more options.
   #
   def get
     option_name, option_argument = nil, ''
@@ -585,21 +829,32 @@ class GetoptLong
 
     return @canonical_names[option_name], option_argument
   end
+  alias get_option get
 
   #
-  # `get_option' is an alias of `get'.
+  # Calls the given block with each option;
+  # each option is a 2-element array containing:
   #
-  alias get_option get
-
-  # Iterator version of `get'.
+  # - The option name (the name itself, not an alias).
+  # - The option value.
+  #
+  # Example:
+  #
+  #   :include: ../sample/getoptlong/each.rb
   #
-  # The block is called repeatedly with two arguments:
-  # The first is the option name.
-  # The second is the argument which followed it (if any).
-  # Example: ('--opt', 'value')
+  # Command line:
   #
-  # The option name is always converted to the first (preferred)
-  # name given in the original options to GetoptLong.new.
+  #    ruby each.rb -xxx Foo -x Bar --yyy Baz -y Bat --zzz
+  #
+  # Output:
+  #
+  #   Original ARGV: ["-xxx", "Foo", "-x", "Bar", "--yyy", "Baz", "-y", "Bat", "--zzz"]
+  #   ["--xxx", "xx"]
+  #   ["--xxx", "Bar"]
+  #   ["--yyy", "Baz"]
+  #   ["--yyy", "Bat"]
+  #   ["--zzz", ""]
+  #   Remaining ARGV: ["Foo"]
   #
   def each
     loop do
@@ -608,9 +863,5 @@ class GetoptLong
       yield option_name, option_argument
     end
   end
-
-  #
-  # `each_option' is an alias of `each'.
-  #
   alias each_option each
 end
diff --git a/lib/ipaddr.rb b/lib/ipaddr.rb
index 459b8478a0..7a5cf94830 100644
--- a/lib/ipaddr.rb
+++ b/lib/ipaddr.rb
@@ -40,14 +40,14 @@ require 'socket'
 #   p ipaddr3                   #=> #<IPAddr: IPv4:192.168.2.0/255.255.255.0>
 
 class IPAddr
-  VERSION = "1.2.4"
+  VERSION = "1.2.5"
 
   # 32 bit mask for IPv4
   IN4MASK = 0xffffffff
   # 128 bit mask for IPv6
   IN6MASK = 0xffffffffffffffffffffffffffffffff
   # Format string for IPv6
-  IN6FORMAT = (["%.4x"] * 8).join(':')
+  IN6FORMAT = (["%.4x"] * 8).join(':').freeze
 
   # Regexp _internally_ used for parsing IPv4 address.
   RE_IPV4ADDRLIKE = %r{
@@ -736,7 +736,7 @@ end
 unless Socket.const_defined? :AF_INET6
   class Socket < BasicSocket
     # IPv6 protocol family
-    AF_INET6 = Object.new
+    AF_INET6 = Object.new.freeze
   end
 
   class << IPSocket
diff --git a/lib/irb.rb b/lib/irb.rb
index 6887d5596e..2db99bcd43 100644
--- a/lib/irb.rb
+++ b/lib/irb.rb
@@ -51,61 +51,63 @@ require_relative "irb/easter-egg"
 #
 # == Command line options
 #
-#   Usage:  irb.rb [options] [programfile] [arguments]
-#     -f                Suppress read of ~/.irbrc
-#     -d                Set $DEBUG to true (same as `ruby -d')
-#     -r load-module    Same as `ruby -r'
-#     -I path           Specify $LOAD_PATH directory
-#     -U                Same as `ruby -U`
-#     -E enc            Same as `ruby -E`
-#     -w                Same as `ruby -w`
-#     -W[level=2]       Same as `ruby -W`
-#     --context-mode n  Set n[0-4] to method to create Binding Object,
-#                       when new workspace was created
-#     --extra-doc-dir   Add an extra doc dir for the doc dialog
-#     --echo            Show result (default)
-#     --noecho          Don't show result
-#     --echo-on-assignment
-#                       Show result on assignment
-#     --noecho-on-assignment
-#                       Don't show result on assignment
-#     --truncate-echo-on-assignment
-#                       Show truncated result on assignment (default)
-#     --inspect         Use `inspect' for output
-#     --noinspect       Don't use inspect for output
-#     --multiline       Use multiline editor module
-#     --nomultiline     Don't use multiline editor module
-#     --singleline      Use singleline editor module
-#     --nosingleline    Don't use singleline editor module
-#     --colorize        Use colorization
-#     --nocolorize      Don't use colorization
-#     --autocomplete    Use autocompletion
-#     --noautocomplete  Don't use autocompletion
-#     --prompt prompt-mode/--prompt-mode prompt-mode
-#                       Switch prompt mode. Pre-defined prompt modes are
-#                       `default', `simple', `xmp' and `inf-ruby'
-#     --inf-ruby-mode   Use prompt appropriate for inf-ruby-mode on emacs.
-#                       Suppresses --multiline and --singleline.
-#     --sample-book-mode/--simple-prompt
-#                       Simple prompt mode
-#     --noprompt        No prompt mode
-#     --single-irb      Share self with sub-irb.
-#     --tracer          Display trace for each execution of commands.
-#     --back-trace-limit n
-#                       Display backtrace top n and tail n. The default
-#                       value is 16.
-#     --verbose         Show details
-#     --noverbose       Don't show details
-#     -v, --version	    Print the version of irb
-#     -h, --help        Print help
-#     --                Separate options of irb from the list of command-line args
+#   :include: ./irb/lc/help-message
+#
+# == Commands
+#
+# The following commands are available on IRB.
+#
+# * cwws
+#   * Show the current workspace.
+# * cb, cws, chws
+#   * Change the current workspace to an object.
+# * bindings, workspaces
+#   * Show workspaces.
+# * pushb, pushws
+#   * Push an object to the workspace stack.
+# * popb, popws
+#   * Pop a workspace from the workspace stack.
+# * load
+#   * Load a Ruby file.
+# * require
+#   * Require a Ruby file.
+# * source
+#   * Loads a given file in the current session.
+# * irb
+#   * Start a child IRB.
+# * jobs
+#   * List of current sessions.
+# * fg
+#   * Switches to the session of the given number.
+# * kill
+#   * Kills the session with the given number.
+# * help
+#   * Enter the mode to look up RI documents.
+# * irb_info
+#   * Show information about IRB.
+# * ls
+#   * Show methods, constants, and variables.
+#     -g [query] or -G [query] allows you to filter out the output.
+# * measure
+#   * measure enables the mode to measure processing time. measure :off disables it.
+# * $, show_source
+#   * Show the source code of a given method or constant.
+# * @, whereami
+#   * Show the source code around binding.irb again.
+# * debug
+#   * Start the debugger of debug.gem.
+# * break, delete, next, step, continue, finish, backtrace, info, catch
+#   * Start the debugger of debug.gem and run the command on it.
 #
 # == Configuration
 #
-# IRB reads from <code>~/.irbrc</code> when it's invoked.
-#
-# If <code>~/.irbrc</code> doesn't exist, +irb+ will try to read in the following order:
+# IRB reads a personal initialization file when it's invoked.
+# IRB searches a file in the following order and loads the first one found.
 #
+# * <tt>$IRBRC</tt> (if <tt>$IRBRC</tt> is set)
+# * <tt>$XDG_CONFIG_HOME/irb/irbrc</tt> (if <tt>$XDG_CONFIG_HOME</tt> is set)
+# * <tt>~/.irbrc</tt>
+# * +.config/irb/irbrc+
 # * +.irbrc+
 # * +irb.rc+
 # * +_irbrc+
@@ -137,9 +139,9 @@ require_relative "irb/easter-egg"
 #
 # === Autocompletion
 #
-# To enable autocompletion for irb, add the following to your +.irbrc+:
+# To disable autocompletion for irb, add the following to your +.irbrc+:
 #
-#     require 'irb/completion'
+#     IRB.conf[:USE_AUTOCOMPLETE] = false
 #
 # === History
 #
@@ -433,11 +435,7 @@ module IRB
   #
   # Will raise an Abort exception, or the given +exception+.
   def IRB.irb_abort(irb, exception = Abort)
-    if defined? Thread
-      irb.context.thread.raise exception, "abort then interrupt!"
-    else
-      raise exception, "abort then interrupt!"
-    end
+    irb.context.thread.raise exception, "abort then interrupt!"
   end
 
   class Irb
@@ -478,6 +476,17 @@ module IRB
       @scanner = RubyLex.new
     end
 
+    # A hook point for `debug` command's TracePoint after :IRB_EXIT as well as its clean-up
+    def debug_break
+      # it means the debug command is executed
+      if defined?(DEBUGGER__) && DEBUGGER__.respond_to?(:capture_frames_without_irb)
+        # after leaving this initial breakpoint, revert the capture_frames patch
+        DEBUGGER__.singleton_class.send(:alias_method, :capture_frames, :capture_frames_without_irb)
+        # and remove the redundant method
+        DEBUGGER__.singleton_class.send(:undef_method, :capture_frames_without_irb)
+      end
+    end
+
     def run(conf = IRB.conf)
       conf[:IRB_RC].call(context) if conf[:IRB_RC]
       conf[:MAIN_CONTEXT] = context
@@ -554,13 +563,15 @@ module IRB
 
       @scanner.set_auto_indent(@context) if @context.auto_indent_mode
 
-      @scanner.each_top_level_statement do |line, line_no|
+      @scanner.each_top_level_statement(@context) do |line, line_no|
         signal_status(:IN_EVAL) do
           begin
             line.untaint if RUBY_VERSION < '2.7'
             if IRB.conf[:MEASURE] && IRB.conf[:MEASURE_CALLBACKS].empty?
               IRB.set_measure_callback
             end
+            # Assignment expression check should be done before @context.evaluate to handle code like `a /2#/ if false; a = 1`
+            is_assignment = assignment_expression?(line)
             if IRB.conf[:MEASURE] && !IRB.conf[:MEASURE_CALLBACKS].empty?
               result = nil
               last_proc = proc{ result = @context.evaluate(line, line_no, exception: exc) }
@@ -577,7 +588,7 @@ module IRB
               @context.evaluate(line, line_no, exception: exc)
             end
             if @context.echo?
-              if assignment_expression?(line)
+              if is_assignment
                 if @context.echo_on_assignment?
                   output_value(@context.echo_on_assignment? == :truncate)
                 end
@@ -640,11 +651,7 @@ module IRB
 
       if exc.backtrace
         order = nil
-        if '2.5.0' == RUBY_VERSION
-          # Exception#full_message doesn't have keyword arguments.
-          message = exc.full_message # the same of (highlight: true, order: bottom)
-          order = :bottom
-        elsif '2.5.1' <= RUBY_VERSION && RUBY_VERSION < '3.0.0'
+        if RUBY_VERSION < '3.0.0'
           if STDOUT.tty?
             message = exc.full_message(order: :bottom)
             order = :bottom
@@ -825,11 +832,11 @@ module IRB
           if diff_size.positive? and output_width > winwidth
             lines, _ = Reline::Unicode.split_by_width(first_line, winwidth - diff_size - 3)
             str = "%s..." % lines.first
-            str += "\e[0m" if @context.use_colorize
+            str += "\e[0m" if Color.colorable?
             multiline_p = false
           else
             str = str.gsub(/(\A.*?\n).*/m, "\\1...")
-            str += "\e[0m" if @context.use_colorize
+            str += "\e[0m" if Color.colorable?
           end
         else
           output_width = Reline::Unicode.calculate_width(@context.return_format % str, true)
@@ -837,7 +844,7 @@ module IRB
           if diff_size.positive? and output_width > winwidth
             lines, _ = Reline::Unicode.split_by_width(str, winwidth - diff_size - 3)
             str = "%s..." % lines.first
-            str += "\e[0m" if @context.use_colorize
+            str += "\e[0m" if Color.colorable?
           end
         end
       end
@@ -875,9 +882,12 @@ module IRB
       # array of parsed expressions. The first element of each expression is the
       # expression's type.
       verbose, $VERBOSE = $VERBOSE, nil
-      result = ASSIGNMENT_NODE_TYPES.include?(Ripper.sexp(line)&.dig(1,-1,0))
+      code = "#{RubyLex.generate_local_variables_assign_code(@context.local_variables) || 'nil;'}\n#{line}"
+      # Get the last node_type of the line. drop(1) is to ignore the local_variables_assign_code part.
+      node_type = Ripper.sexp(code)&.dig(1)&.drop(1)&.dig(-1, 0)
+      ASSIGNMENT_NODE_TYPES.include?(node_type)
+    ensure
       $VERBOSE = verbose
-      result
     end
 
     ATTR_TTY = "\e[%sm"
@@ -967,12 +977,13 @@ class Binding
   #
   #
   # See IRB@IRB+Usage for more information.
-  def irb
+  def irb(show_code: true)
     IRB.setup(source_location[0], argv: [])
     workspace = IRB::WorkSpace.new(self)
-    STDOUT.print(workspace.code_around_binding)
+    STDOUT.print(workspace.code_around_binding) if show_code
     binding_irb = IRB::Irb.new(workspace)
     binding_irb.context.irb_path = File.expand_path(source_location[0])
     binding_irb.run(IRB.conf)
+    binding_irb.debug_break
   end
 end
diff --git a/lib/irb/cmd/backtrace.rb b/lib/irb/cmd/backtrace.rb
new file mode 100644
index 0000000000..f632894618
--- /dev/null
+++ b/lib/irb/cmd/backtrace.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+require_relative "debug"
+
+module IRB
+  # :stopdoc:
+
+  module ExtendCommand
+    class Backtrace < DebugCommand
+      def self.transform_args(args)
+        args&.dump
+      end
+
+      def execute(*args)
+        super(pre_cmds: ["backtrace", *args].join(" "))
+      end
+    end
+  end
+
+  # :startdoc:
+end
diff --git a/lib/irb/cmd/break.rb b/lib/irb/cmd/break.rb
new file mode 100644
index 0000000000..df259a90ca
--- /dev/null
+++ b/lib/irb/cmd/break.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+require_relative "debug"
+
+module IRB
+  # :stopdoc:
+
+  module ExtendCommand
+    class Break < DebugCommand
+      def self.transform_args(args)
+        args&.dump
+      end
+
+      def execute(args = nil)
+        super(pre_cmds: "break #{args}")
+      end
+    end
+  end
+
+  # :startdoc:
+end
diff --git a/lib/irb/cmd/catch.rb b/lib/irb/cmd/catch.rb
new file mode 100644
index 0000000000..40b62c7533
--- /dev/null
+++ b/lib/irb/cmd/catch.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+require_relative "debug"
+
+module IRB
+  # :stopdoc:
+
+  module ExtendCommand
+    class Catch < DebugCommand
+      def self.transform_args(args)
+        args&.dump
+      end
+
+      def execute(*args)
+        super(pre_cmds: ["catch", *args].join(" "))
+      end
+    end
+  end
+
+  # :startdoc:
+end
diff --git a/lib/irb/cmd/chws.rb b/lib/irb/cmd/chws.rb
index b28c090686..7c84ba0a4b 100644
--- a/lib/irb/cmd/chws.rb
+++ b/lib/irb/cmd/chws.rb
@@ -19,12 +19,18 @@ module IRB
   module ExtendCommand
 
     class CurrentWorkingWorkspace < Nop
+      category "IRB"
+      description "Show the current workspace."
+
       def execute(*obj)
         irb_context.main
       end
     end
 
     class ChangeWorkspace < Nop
+      category "IRB"
+      description "Change the current workspace to an object."
+
       def execute(*obj)
         irb_context.change_workspace(*obj)
         irb_context.main
diff --git a/lib/irb/cmd/continue.rb b/lib/irb/cmd/continue.rb
new file mode 100644
index 0000000000..9136177eef
--- /dev/null
+++ b/lib/irb/cmd/continue.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+require_relative "debug"
+
+module IRB
+  # :stopdoc:
+
+  module ExtendCommand
+    class Continue < DebugCommand
+      def execute(*args)
+        super(do_cmds: ["continue", *args].join(" "))
+      end
+    end
+  end
+
+  # :startdoc:
+end
diff --git a/lib/irb/cmd/debug.rb b/lib/irb/cmd/debug.rb
new file mode 100644
index 0000000000..7d39b9fa27
--- /dev/null
+++ b/lib/irb/cmd/debug.rb
@@ -0,0 +1,136 @@
+require_relative "nop"
+
+module IRB
+  # :stopdoc:
+
+  module ExtendCommand
+    class Debug < Nop
+      category "Debugging"
+      description "Start the debugger of debug.gem."
+
+      BINDING_IRB_FRAME_REGEXPS = [
+        '<internal:prelude>',
+        binding.method(:irb).source_location.first,
+      ].map { |file| /\A#{Regexp.escape(file)}:\d+:in `irb'\z/ }
+      IRB_DIR = File.expand_path('..', __dir__)
+
+      def execute(pre_cmds: nil, do_cmds: nil)
+        unless binding_irb?
+          puts "`debug` command is only available when IRB is started with binding.irb"
+          return
+        end
+
+        unless setup_debugger
+          puts <<~MSG
+            You need to install the debug gem before using this command.
+            If you use `bundle exec`, please add `gem "debug"` into your Gemfile.
+          MSG
+          return
+        end
+
+        options = { oneshot: true, hook_call: false }
+        if pre_cmds || do_cmds
+          options[:command] = ['irb', pre_cmds, do_cmds]
+        end
+        if DEBUGGER__::LineBreakpoint.instance_method(:initialize).parameters.include?([:key, :skip_src])
+          options[:skip_src] = true
+        end
+
+        # To make debugger commands like `next` or `continue` work without asking
+        # the user to quit IRB after that, we need to exit IRB first and then hit
+        # a TracePoint on #debug_break.
+        file, lineno = IRB::Irb.instance_method(:debug_break).source_location
+        DEBUGGER__::SESSION.add_line_breakpoint(file, lineno + 1, **options)
+        # exit current Irb#run call
+        throw :IRB_EXIT
+      end
+
+      private
+
+      def binding_irb?
+        caller.any? do |frame|
+          BINDING_IRB_FRAME_REGEXPS.any? do |regexp|
+            frame.match?(regexp)
+          end
+        end
+      end
+
+      module SkipPathHelperForIRB
+        def skip_internal_path?(path)
+          # The latter can be removed once https://github.com/ruby/debug/issues/866 is resolved
+          super || path.match?(IRB_DIR) || path.match?('<internal:prelude>')
+        end
+      end
+
+      def setup_debugger
+        unless defined?(DEBUGGER__::SESSION)
+          begin
+            require "debug/session"
+          rescue LoadError # debug.gem is not written in Gemfile
+            return false unless load_bundled_debug_gem
+          end
+          DEBUGGER__.start(nonstop: true)
+        end
+
+        unless DEBUGGER__.respond_to?(:capture_frames_without_irb)
+          DEBUGGER__.singleton_class.send(:alias_method, :capture_frames_without_irb, :capture_frames)
+
+          def DEBUGGER__.capture_frames(*args)
+            frames = capture_frames_without_irb(*args)
+            frames.reject! do |frame|
+              frame.realpath&.start_with?(IRB_DIR) || frame.path == "<internal:prelude>"
+            end
+            frames
+          end
+
+          DEBUGGER__::ThreadClient.prepend(SkipPathHelperForIRB)
+        end
+
+        true
+      end
+
+      # This is used when debug.gem is not written in Gemfile. Even if it's not
+      # installed by `bundle install`, debug.gem is installed by default because
+      # it's a bundled gem. This method tries to activate and load that.
+      def load_bundled_debug_gem
+        # Discover latest debug.gem under GEM_PATH
+        debug_gem = Gem.paths.path.flat_map { |path| Dir.glob("#{path}/gems/debug-*") }.select do |path|
+          File.basename(path).match?(/\Adebug-\d+\.\d+\.\d+(\w+)?\z/)
+        end.sort_by do |path|
+          Gem::Version.new(File.basename(path).delete_prefix('debug-'))
+        end.last
+        return false unless debug_gem
+
+        # Discover debug/debug.so under extensions for Ruby 3.2+
+        ext_name = "/debug/debug.#{RbConfig::CONFIG['DLEXT']}"
+        ext_path = Gem.paths.path.flat_map do |path|
+          Dir.glob("#{path}/extensions/**/#{File.basename(debug_gem)}#{ext_name}")
+        end.first
+
+        # Attempt to forcibly load the bundled gem
+        if ext_path
+          $LOAD_PATH << ext_path.delete_suffix(ext_name)
+        end
+        $LOAD_PATH << "#{debug_gem}/lib"
+        begin
+          require "debug/session"
+          puts "Loaded #{File.basename(debug_gem)}"
+          true
+        rescue LoadError
+          false
+        end
+      end
+    end
+
+    class DebugCommand < Debug
+      def self.category
+        "Debugging"
+      end
+
+      def self.description
+        command_name = self.name.split("::").last.downcase
+        "Start the debugger of debug.gem and run its `#{command_name}` command."
+      end
+    end
+  end
+end
diff --git a/lib/irb/cmd/delete.rb b/lib/irb/cmd/delete.rb
new file mode 100644
index 0000000000..aeb26d2572
--- /dev/null
+++ b/lib/irb/cmd/delete.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+require_relative "debug"
+
+module IRB
+  # :stopdoc:
+
+  module ExtendCommand
+    class Delete < DebugCommand
+      def execute(*args)
+        super(pre_cmds: ["delete", *args].join(" "))
+      end
+    end
+  end
+
+  # :startdoc:
+end
diff --git a/lib/irb/cmd/edit.rb b/lib/irb/cmd/edit.rb
new file mode 100644
index 0000000000..0103891cf4
--- /dev/null
+++ b/lib/irb/cmd/edit.rb
@@ -0,0 +1,61 @@
+require 'shellwords'
+require_relative "nop"
+
+module IRB
+  # :stopdoc:
+
+  module ExtendCommand
+    class Edit < Nop
+      category "Misc"
+      description 'Open a file with the editor command defined with `ENV["EDITOR"]`.'
+
+      class << self
+        def transform_args(args)
+          # Return a string literal as is for backward compatibility
+          if args.nil? || args.empty? || string_literal?(args)
+            args
+          else # Otherwise, consider the input as a String for convenience
+            args.strip.dump
+          end
+        end
+      end
+
+      def execute(*args)
+        path = args.first
+
+        if path.nil? && (irb_path = @irb_context.irb_path)
+          path = irb_path
+        end
+
+        if !File.exist?(path)
+          require_relative "show_source"
+
+          source =
+            begin
+              ShowSource.find_source(path, @irb_context)
+            rescue NameError
+              # if user enters a path that doesn't exist, it'll cause NameError when passed here because find_source would try to evaluate it as well
+              # in this case, we should just ignore the error
+            end
+
+          if source && File.exist?(source.file)
+            path = source.file
+          else
+            puts "Can not find file: #{path}"
+            return
+          end
+        end
+
+        if editor = ENV['EDITOR']
+          puts "command: '#{editor}'"
+          puts "   path: #{path}"
+          system(*Shellwords.split(editor), path)
+        else
+          puts "Can not find editor setting: ENV['EDITOR']"
+        end
+      end
+    end
+  end
+
+  # :startdoc:
+end
diff --git a/lib/irb/cmd/finish.rb b/lib/irb/cmd/finish.rb
new file mode 100644
index 0000000000..29f100feb5
--- /dev/null
+++ b/lib/irb/cmd/finish.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+require_relative "debug"
+
+module IRB
+  # :stopdoc:
+
+  module ExtendCommand
+    class Finish < DebugCommand
+      def execute(*args)
+        super(do_cmds: ["finish", *args].join(" "))
+      end
+    end
+  end
+
+  # :startdoc:
+end
diff --git a/lib/irb/cmd/help.rb b/lib/irb/cmd/help.rb
index 0497c57457..2a135cdb14 100644
--- a/lib/irb/cmd/help.rb
+++ b/lib/irb/cmd/help.rb
@@ -16,6 +16,20 @@ module IRB
 
   module ExtendCommand
     class Help < Nop
+      class << self
+        def transform_args(args)
+          # Return a string literal as is for backward compatibility
+          if args.empty? || string_literal?(args)
+            args
+          else # Otherwise, consider the input as a String for convenience
+            args.strip.dump
+          end
+        end
+      end
+
+      category "Context"
+      description "Enter the mode to look up RI documents."
+
       def execute(*names)
         require 'rdoc/ri/driver'
         opts = RDoc::RI::Driver.process_args([])
diff --git a/lib/irb/cmd/info.rb b/lib/irb/cmd/info.rb
index 37ecd762ff..2c0a32b34f 100644
--- a/lib/irb/cmd/info.rb
+++ b/lib/irb/cmd/info.rb
@@ -1,31 +1,18 @@
-# frozen_string_literal: false
+# frozen_string_literal: true
 
-require_relative "nop"
+require_relative "debug"
 
 module IRB
   # :stopdoc:
 
   module ExtendCommand
-    class Info < Nop
-      def execute
-        Class.new {
-          def inspect
-            str  = "Ruby version: #{RUBY_VERSION}\n"
-            str += "IRB version: #{IRB.version}\n"
-            str += "InputMethod: #{IRB.CurrentContext.io.inspect}\n"
-            str += ".irbrc path: #{IRB.rc_file}\n" if File.exist?(IRB.rc_file)
-            str += "RUBY_PLATFORM: #{RUBY_PLATFORM}\n"
-            str += "LANG env: #{ENV["LANG"]}\n" if ENV["LANG"] && !ENV["LANG"].empty?
-            str += "LC_ALL env: #{ENV["LC_ALL"]}\n" if ENV["LC_ALL"] && !ENV["LC_ALL"].empty?
-            str += "East Asian Ambiguous Width: #{Reline.ambiguous_width.inspect}\n"
-            if RbConfig::CONFIG['host_os'] =~ /mswin|msys|mingw|cygwin|bccwin|wince|emc/
-              codepage = `chcp`.b.sub(/.*: (\d+)\n/, '\1')
-              str += "Code page: #{codepage}\n"
-            end
-            str
-          end
-          alias_method :to_s, :inspect
-        }.new
+    class Info < DebugCommand
+      def self.transform_args(args)
+        args&.dump
+      end
+
+      def execute(*args)
+        super(pre_cmds: ["info", *args].join(" "))
       end
     end
   end
diff --git a/lib/irb/cmd/irb_info.rb b/lib/irb/cmd/irb_info.rb
new file mode 100644
index 0000000000..da11e8d40b
--- /dev/null
+++ b/lib/irb/cmd/irb_info.rb
@@ -0,0 +1,37 @@
+# frozen_string_literal: false
+
+require_relative "nop"
+
+module IRB
+  # :stopdoc:
+
+  module ExtendCommand
+    class IrbInfo < Nop
+      category "IRB"
+      description "Show information about IRB."
+
+      def execute
+        Class.new {
+          def inspect
+            str  = "Ruby version: #{RUBY_VERSION}\n"
+            str += "IRB version: #{IRB.version}\n"
+            str += "InputMethod: #{IRB.CurrentContext.io.inspect}\n"
+            str += ".irbrc path: #{IRB.rc_file}\n" if File.exist?(IRB.rc_file)
+            str += "RUBY_PLATFORM: #{RUBY_PLATFORM}\n"
+            str += "LANG env: #{ENV["LANG"]}\n" if ENV["LANG"] && !ENV["LANG"].empty?
+            str += "LC_ALL env: #{ENV["LC_ALL"]}\n" if ENV["LC_ALL"] && !ENV["LC_ALL"].empty?
+            str += "East Asian Ambiguous Width: #{Reline.ambiguous_width.inspect}\n"
+            if RbConfig::CONFIG['host_os'] =~ /mswin|msys|mingw|cygwin|bccwin|wince|emc/
+              codepage = `chcp`.b.sub(/.*: (\d+)\n/, '\1')
+              str += "Code page: #{codepage}\n"
+            end
+            str
+          end
+          alias_method :to_s, :inspect
+        }.new
+      end
+    end
+  end
+
+  # :startdoc:
+end
diff --git a/lib/irb/cmd/load.rb b/lib/irb/cmd/load.rb
index 2c5c01e89c..2897bbd975 100644
--- a/lib/irb/cmd/load.rb
+++ b/lib/irb/cmd/load.rb
@@ -17,18 +17,29 @@ module IRB
   # :stopdoc:
 
   module ExtendCommand
-    class Load < Nop
+    class LoaderCommand < Nop
       include IrbLoader
 
-      def execute(file_name, priv = nil)
-        return irb_load(file_name, priv)
+      def raise_cmd_argument_error
+        raise CommandArgumentError.new("Please specify the file name.")
       end
     end
 
-    class Require < Nop
-      include IrbLoader
+    class Load < LoaderCommand
+      category "IRB"
+      description "Load a Ruby file."
+
+      def execute(file_name = nil, priv = nil)
+        raise_cmd_argument_error unless file_name
+        irb_load(file_name, priv)
+      end
+    end
 
-      def execute(file_name)
+    class Require < LoaderCommand
+      category "IRB"
+      description "Require a Ruby file."
+      def execute(file_name = nil)
+        raise_cmd_argument_error unless file_name
 
         rex = Regexp.new("#{Regexp.quote(file_name)}(\.o|\.rb)?")
         return false if $".find{|f| f =~ rex}
@@ -56,13 +67,16 @@ module IRB
       end
     end
 
-    class Source < Nop
-      include IrbLoader
-      def execute(file_name)
+    class Source < LoaderCommand
+      category "IRB"
+      description "Loads a given file in the current session."
+
+      def execute(file_name = nil)
+        raise_cmd_argument_error unless file_name
+
         source_file(file_name)
       end
     end
   end
-
   # :startdoc:
 end
diff --git a/lib/irb/cmd/ls.rb b/lib/irb/cmd/ls.rb
index f4a7348bd1..b65fae2bf1 100644
--- a/lib/irb/cmd/ls.rb
+++ b/lib/irb/cmd/ls.rb
@@ -9,6 +9,18 @@ module IRB
 
   module ExtendCommand
     class Ls < Nop
+      category "Context"
+      description "Show methods, constants, and variables. `-g [query]` or `-G [query]` allows you to filter out the output."
+
+      def self.transform_args(args)
+        if match = args&.match(/\A(?<args>.+\s|)(-g|-G)\s+(?<grep>[^\s]+)\s*\n\z/)
+          args = match[:args]
+          "#{args}#{',' unless args.chomp.empty?} grep: /#{match[:grep]}/"
+        else
+          args
+        end
+      end
+
       def execute(*arg, grep: nil)
         o = Output.new(grep: grep)
 
@@ -21,6 +33,7 @@ module IRB
         o.dump("instance variables", obj.instance_variables)
         o.dump("class variables", klass.class_variables)
         o.dump("locals", locals)
+        nil
       end
 
       def dump_methods(o, klass, obj)
diff --git a/lib/irb/cmd/measure.rb b/lib/irb/cmd/measure.rb
index a97baee9f1..9122e2dac9 100644
--- a/lib/irb/cmd/measure.rb
+++ b/lib/irb/cmd/measure.rb
@@ -5,6 +5,9 @@ module IRB
 
   module ExtendCommand
     class Measure < Nop
+      category "Misc"
+      description "`measure` enables the mode to measure processing time. `measure :off` disables it."
+
       def initialize(*args)
         super(*args)
       end
diff --git a/lib/irb/cmd/next.rb b/lib/irb/cmd/next.rb
new file mode 100644
index 0000000000..d29c82e7fc
--- /dev/null
+++ b/lib/irb/cmd/next.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+require_relative "debug"
+
+module IRB
+  # :stopdoc:
+
+  module ExtendCommand
+    class Next < DebugCommand
+      def execute(*args)
+        super(do_cmds: ["next", *args].join(" "))
+      end
+    end
+  end
+
+  # :startdoc:
+end
diff --git a/lib/irb/cmd/nop.rb b/lib/irb/cmd/nop.rb
index 881a736722..c616c054a8 100644
--- a/lib/irb/cmd/nop.rb
+++ b/lib/irb/cmd/nop.rb
@@ -13,17 +13,41 @@ module IRB
   # :stopdoc:
 
   module ExtendCommand
+    class CommandArgumentError < StandardError; end
+
     class Nop
+      class << self
+        def category(category = nil)
+          @category = category if category
+          @category
+        end
+
+        def description(description = nil)
+          @description = description if description
+          @description
+        end
+
+        private
+
+        def string_literal?(args)
+          sexp = Ripper.sexp(args)
+          sexp && sexp.size == 2 && sexp.last&.first&.first == :string_literal
+        end
+      end
 
       if RUBY_ENGINE == "ruby" && RUBY_VERSION >= "2.7.0"
         def self.execute(conf, *opts, **kwargs, &block)
           command = new(conf)
           command.execute(*opts, **kwargs, &block)
+        rescue CommandArgumentError => e
+          puts e.message
         end
       else
         def self.execute(conf, *opts, &block)
           command = new(conf)
           command.execute(*opts, &block)
+        rescue CommandArgumentError => e
+          puts e.message
         end
       end
 
diff --git a/lib/irb/cmd/pushws.rb b/lib/irb/cmd/pushws.rb
index 791d8f8dbb..41d2e705f1 100644
--- a/lib/irb/cmd/pushws.rb
+++ b/lib/irb/cmd/pushws.rb
@@ -18,12 +18,18 @@ module IRB
 
   module ExtendCommand
     class Workspaces < Nop
+      category "IRB"
+      description "Show workspaces."
+
       def execute(*obj)
         irb_context.workspaces.collect{|ws| ws.main}
       end
     end
 
     class PushWorkspace < Workspaces
+      category "IRB"
+      description "Push an object to the workspace stack."
+
       def execute(*obj)
         irb_context.push_workspace(*obj)
         super
@@ -31,6 +37,9 @@ module IRB
     end
 
     class PopWorkspace < Workspaces
+      category "IRB"
+      description "Pop a workspace from the workspace stack."
+
       def execute(*obj)
         irb_context.pop_workspace(*obj)
         super
diff --git a/lib/irb/cmd/show_cmds.rb b/lib/irb/cmd/show_cmds.rb
new file mode 100644
index 0000000000..acced27d48
--- /dev/null
+++ b/lib/irb/cmd/show_cmds.rb
@@ -0,0 +1,39 @@
+# frozen_string_literal: true
+
+require "stringio"
+require_relative "nop"
+
+module IRB
+  # :stopdoc:
+
+  module ExtendCommand
+    class ShowCmds < Nop
+      category "IRB"
+      description "List all available commands and their description."
+
+      def execute(*args)
+        commands_info = IRB::ExtendCommandBundle.all_commands_info
+        commands_grouped_by_categories = commands_info.group_by { |cmd| cmd[:category] }
+        longest_cmd_name_length = commands_info.map { |c| c[:display_name] }.max { |a, b| a.length <=> b.length }.length
+
+        output = StringIO.new
+
+        commands_grouped_by_categories.each do |category, cmds|
+          output.puts Color.colorize(category, [:BOLD])
+
+          cmds.each do |cmd|
+            output.puts "  #{cmd[:display_name].to_s.ljust(longest_cmd_name_length)}    #{cmd[:description]}"
+          end
+
+          output.puts
+        end
+
+        puts output.string
+
+        nil
+      end
+    end
+  end
+
+  # :startdoc:
+end
diff --git a/lib/irb/cmd/show_source.rb b/lib/irb/cmd/show_source.rb
index f8a17822df..ea700be4bf 100644
--- a/lib/irb/cmd/show_source.rb
+++ b/lib/irb/cmd/show_source.rb
@@ -9,12 +9,71 @@ module IRB
 
   module ExtendCommand
     class ShowSource < Nop
+      category "Context"
+      description "Show the source code of a given method or constant."
+
+      class << self
+        def transform_args(args)
+          # Return a string literal as is for backward compatibility
+          if args.empty? || string_literal?(args)
+            args
+          else # Otherwise, consider the input as a String for convenience
+            args.strip.dump
+          end
+        end
+
+        def find_source(str, irb_context)
+          case str
+          when /\A[A-Z]\w*(::[A-Z]\w*)*\z/ # Const::Name
+            eval(str, irb_context.workspace.binding) # trigger autoload
+            base = irb_context.workspace.binding.receiver.yield_self { |r| r.is_a?(Module) ? r : Object }
+            file, line = base.const_source_location(str) if base.respond_to?(:const_source_location) # Ruby 2.7+
+          when /\A(?<owner>[A-Z]\w*(::[A-Z]\w*)*)#(?<method>[^ :.]+)\z/ # Class#method
+            owner = eval(Regexp.last_match[:owner], irb_context.workspace.binding)
+            method = Regexp.last_match[:method]
+            if owner.respond_to?(:instance_method) && owner.instance_methods.include?(method.to_sym)
+              file, line = owner.instance_method(method).source_location
+            end
+          when /\A((?<receiver>.+)(\.|::))?(?<method>[^ :.]+)\z/ # method, receiver.method, receiver::method
+            receiver = eval(Regexp.last_match[:receiver] || 'self', irb_context.workspace.binding)
+            method = Regexp.last_match[:method]
+            file, line = receiver.method(method).source_location if receiver.respond_to?(method)
+          end
+          if file && line
+            Source.new(file: file, first_line: line, last_line: find_end(file, line))
+          end
+        end
+
+        private
+
+        def find_end(file, first_line)
+          return first_line unless File.exist?(file)
+          lex = RubyLex.new
+          lines = File.read(file).lines[(first_line - 1)..-1]
+          tokens = RubyLex.ripper_lex_without_warning(lines.join)
+          prev_tokens = []
+
+          # chunk with line number
+          tokens.chunk { |tok| tok.pos[0] }.each do |lnum, chunk|
+            code = lines[0..lnum].join
+            prev_tokens.concat chunk
+            continue = lex.process_continue(prev_tokens)
+            code_block_open = lex.check_code_block(code, prev_tokens)
+            if !continue && !code_block_open
+              return first_line + lnum
+            end
+          end
+          first_line
+        end
+      end
+
       def execute(str = nil)
         unless str.is_a?(String)
           puts "Error: Expected a string but got #{str.inspect}"
           return
         end
-        source = find_source(str)
+
+        source = self.class.find_source(str, @irb_context)
         if source && File.exist?(source.file)
           show_source(source)
         else
@@ -35,48 +94,6 @@ module IRB
         puts
       end
 
-      def find_source(str)
-        case str
-        when /\A[A-Z]\w*(::[A-Z]\w*)*\z/ # Const::Name
-          eval(str, irb_context.workspace.binding) # trigger autoload
-          base = irb_context.workspace.binding.receiver.yield_self { |r| r.is_a?(Module) ? r : Object }
-          file, line = base.const_source_location(str) if base.respond_to?(:const_source_location) # Ruby 2.7+
-        when /\A(?<owner>[A-Z]\w*(::[A-Z]\w*)*)#(?<method>[^ :.]+)\z/ # Class#method
-          owner = eval(Regexp.last_match[:owner], irb_context.workspace.binding)
-          method = Regexp.last_match[:method]
-          if owner.respond_to?(:instance_method) && owner.instance_methods.include?(method.to_sym)
-            file, line = owner.instance_method(method).source_location
-          end
-        when /\A((?<receiver>.+)(\.|::))?(?<method>[^ :.]+)\z/ # method, receiver.method, receiver::method
-          receiver = eval(Regexp.last_match[:receiver] || 'self', irb_context.workspace.binding)
-          method = Regexp.last_match[:method]
-          file, line = receiver.method(method).source_location if receiver.respond_to?(method)
-        end
-        if file && line
-          Source.new(file: file, first_line: line, last_line: find_end(file, line))
-        end
-      end
-
-      def find_end(file, first_line)
-        return first_line unless File.exist?(file)
-        lex = RubyLex.new
-        lines = File.read(file).lines[(first_line - 1)..-1]
-        tokens = RubyLex.ripper_lex_without_warning(lines.join)
-        prev_tokens = []
-
-        # chunk with line number
-        tokens.chunk { |tok| tok.pos[0] }.each do |lnum, chunk|
-          code = lines[0..lnum].join
-          prev_tokens.concat chunk
-          continue = lex.process_continue(prev_tokens)
-          code_block_open = lex.check_code_block(code, prev_tokens)
-          if !continue && !code_block_open
-            return first_line + lnum
-          end
-        end
-        first_line
-      end
-
       def bold(str)
         Color.colorize(str, [:BOLD])
       end
diff --git a/lib/irb/cmd/step.rb b/lib/irb/cmd/step.rb
new file mode 100644
index 0000000000..2bc74a9d79
--- /dev/null
+++ b/lib/irb/cmd/step.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+require_relative "debug"
+
+module IRB
+  # :stopdoc:
+
+  module ExtendCommand
+    class Step < DebugCommand
+      def execute(*args)
+        super(do_cmds: ["step", *args].join(" "))
+      end
+    end
+  end
+
+  # :startdoc:
+end
diff --git a/lib/irb/cmd/subirb.rb b/lib/irb/cmd/subirb.rb
index b322aadc53..699b35fcb4 100644
--- a/lib/irb/cmd/subirb.rb
+++ b/lib/irb/cmd/subirb.rb
@@ -10,31 +10,57 @@
 #
 
 require_relative "nop"
-require_relative "../ext/multi-irb"
 
 module IRB
   # :stopdoc:
 
   module ExtendCommand
-    class IrbCommand < Nop
+    class MultiIRBCommand < Nop
+      def initialize(conf)
+        super
+        extend_irb_context
+      end
+
+      private
+
+      def extend_irb_context
+        # this extension patches IRB context like IRB.CurrentContext
+        require_relative "../ext/multi-irb"
+      end
+    end
+
+    class IrbCommand < MultiIRBCommand
+      category "IRB"
+      description "Start a child IRB."
+
       def execute(*obj)
         IRB.irb(nil, *obj)
       end
     end
 
-    class Jobs < Nop
+    class Jobs < MultiIRBCommand
+      category "IRB"
+      description "List of current sessions."
+
       def execute
         IRB.JobManager
       end
     end
 
-    class Foreground < Nop
-      def execute(key)
+    class Foreground < MultiIRBCommand
+      category "IRB"
+      description "Switches to the session of the given number."
+
+      def execute(key = nil)
+        raise CommandArgumentError.new("Please specify the id of target IRB job (listed in the `jobs` command).") unless key
         IRB.JobManager.switch(key)
       end
     end
 
-    class Kill < Nop
+    class Kill < MultiIRBCommand
+      category "IRB"
+      description "Kills the session with the given number."
+
       def execute(*keys)
         IRB.JobManager.kill(*keys)
       end
diff --git a/lib/irb/cmd/whereami.rb b/lib/irb/cmd/whereami.rb
index b8c7e047fa..8f56ba073d 100644
--- a/lib/irb/cmd/whereami.rb
+++ b/lib/irb/cmd/whereami.rb
@@ -7,6 +7,9 @@ module IRB
 
   module ExtendCommand
     class Whereami < Nop
+      category "Context"
+      description "Show the source code around binding.irb again."
+
       def execute(*)
         code = irb_context.workspace.code_around_binding
         if code
diff --git a/lib/irb/color.rb b/lib/irb/color.rb
index f9204f4c98..6378e14856 100644
--- a/lib/irb/color.rb
+++ b/lib/irb/color.rb
@@ -77,7 +77,15 @@ module IRB # :nodoc:
 
     class << self
       def colorable?
-        $stdout.tty? && (/mswin|mingw/ =~ RUBY_PLATFORM || (ENV.key?('TERM') && ENV['TERM'] != 'dumb'))
+        supported = $stdout.tty? && (/mswin|mingw/ =~ RUBY_PLATFORM || (ENV.key?('TERM') && ENV['TERM'] != 'dumb'))
+
+        # because ruby/debug also uses irb's color module selectively,
+        # irb won't be activated in that case.
+        if IRB.respond_to?(:conf)
+          supported && IRB.conf.fetch(:USE_COLORIZE, true)
+        else
+          supported
+        end
       end
 
       def inspect_colorable?(obj, seen: {}.compare_by_identity)
@@ -115,15 +123,21 @@ module IRB # :nodoc:
       # If `complete` is false (code is incomplete), this does not warn compile_error.
       # This option is needed to avoid warning a user when the compile_error is happening
       # because the input is not wrong but just incomplete.
-      def colorize_code(code, complete: true, ignore_error: false, colorable: colorable?)
+      def colorize_code(code, complete: true, ignore_error: false, colorable: colorable?, local_variables: [])
         return code unless colorable
 
         symbol_state = SymbolState.new
         colored = +''
-        length = 0
-        end_seen = false
+        lvars_code = RubyLex.generate_local_variables_assign_code(local_variables)
+        code_with_lvars = lvars_code ? "#{lvars_code}\n#{code}" : code
+
+        scan(code_with_lvars, allow_last_error: !complete) do |token, str, expr|
+          # handle uncolorable code
+          if token.nil?
+            colored << Reline::Unicode.escape_for_print(str)
+            next
+          end
 
-        scan(code, allow_last_error: !complete) do |token, str, expr|
           # IRB::ColorPrinter skips colorizing fragments with any invalid token
           if ignore_error && ERROR_TOKENS.include?(token)
             return Reline::Unicode.escape_for_print(code)
@@ -139,15 +153,12 @@ module IRB # :nodoc:
               colored << line
             end
           end
-          length += str.bytesize
-          end_seen = true if token == :on___end__
         end
 
-        # give up colorizing incomplete Ripper tokens
-        unless end_seen or length == code.bytesize
-          return Reline::Unicode.escape_for_print(code)
+        if lvars_code
+          raise "#{lvars_code.dump} should have no \\n" if lvars_code.include?("\n")
+          colored.sub!(/\A.+\n/, '') # delete_prefix lvars_code with colors
         end
-
         colored
       end
 
@@ -162,33 +173,42 @@ module IRB # :nodoc:
       end
 
       def scan(code, allow_last_error:)
-        pos = [1, 0]
-
         verbose, $VERBOSE = $VERBOSE, nil
         RubyLex.compile_with_errors_suppressed(code) do |inner_code, line_no|
           lexer = Ripper::Lexer.new(inner_code, '(ripper)', line_no)
-          if lexer.respond_to?(:scan) # Ruby 2.7+
-            lexer.scan.each do |elem|
-              str = elem.tok
-              next if allow_last_error and /meets end of file|unexpected end-of-input/ =~ elem.message
-              next if ([elem.pos[0], elem.pos[1] + str.bytesize] <=> pos) <= 0
+          byte_pos = 0
+          line_positions = [0]
+          inner_code.lines.each do |line|
+            line_positions << line_positions.last + line.bytesize
+          end
+
+          on_scan = proc do |elem|
+            start_pos = line_positions[elem.pos[0] - 1] + elem.pos[1]
 
-              str.each_line do |line|
-                if line.end_with?("\n")
-                  pos[0] += 1
-                  pos[1] = 0
-                else
-                  pos[1] += line.bytesize
-                end
-              end
+            # yield uncolorable code
+            if byte_pos < start_pos
+              yield(nil, inner_code.byteslice(byte_pos...start_pos), nil)
+            end
 
+            if byte_pos <= start_pos
+              str = elem.tok
               yield(elem.event, str, elem.state)
+              byte_pos = start_pos + str.bytesize
+            end
+          end
+
+          if lexer.respond_to?(:scan) # Ruby 2.7+
+            lexer.scan.each do |elem|
+              next if allow_last_error and /meets end of file|unexpected end-of-input/ =~ elem.message
+              on_scan.call(elem)
             end
           else
-            lexer.parse.each do |elem|
-              yield(elem.event, elem.tok, elem.state)
+            lexer.parse.sort_by(&:pos).each do |elem|
+              on_scan.call(elem)
             end
           end
+          # yield uncolorable DATA section
+          yield(nil, inner_code.byteslice(byte_pos...inner_code.bytesize), nil) if byte_pos < inner_code.bytesize
         end
       ensure
         $VERBOSE = verbose
diff --git a/lib/irb/color_printer.rb b/lib/irb/color_printer.rb
index 78f0b51520..1127bcecb4 100644
--- a/lib/irb/color_printer.rb
+++ b/lib/irb/color_printer.rb
@@ -37,6 +37,9 @@ module IRB
       width ||= str.length
 
       case str
+      when ''
+      when ',', '=>', '[', ']', '{', '}', '..', '...', /\A@\w+\z/
+        super(str, width)
       when /\A#</, '=', '>'
         super(Color.colorize(str, [:GREEN]), width)
       else
diff --git a/lib/irb/completion.rb b/lib/irb/completion.rb
index 9121174a50..34640e17f9 100644
--- a/lib/irb/completion.rb
+++ b/lib/irb/completion.rb
@@ -11,7 +11,29 @@ require_relative 'ruby-lex'
 
 module IRB
   module InputCompletor # :nodoc:
+    using Module.new {
+      refine ::Binding do
+        def eval_methods
+          ::Kernel.instance_method(:methods).bind(eval("self")).call
+        end
+
+        def eval_private_methods
+          ::Kernel.instance_method(:private_methods).bind(eval("self")).call
+        end
 
+        def eval_instance_variables
+          ::Kernel.instance_method(:instance_variables).bind(eval("self")).call
+        end
+
+        def eval_global_variables
+          ::Kernel.instance_method(:global_variables).bind(eval("self")).call
+        end
+
+        def eval_class_constants
+          ::Module.instance_method(:constants).bind(eval("self.class")).call
+        end
+      end
+    }
 
     # Set of reserved words used by Ruby, you should not use these for
     # constants or variables
@@ -42,25 +64,34 @@ module IRB
       if File.respond_to?(:absolute_path?)
         File.absolute_path?(p)
       else
-        if File.absolute_path(p) == p
-          true
-        else
-          false
-        end
+        File.absolute_path(p) == p
       end
     end
 
+    GEM_PATHS =
+      if defined?(Gem::Specification)
+        Gem::Specification.latest_specs(true).map { |s|
+          s.require_paths.map { |p|
+            if absolute_path?(p)
+              p
+            else
+              File.join(s.full_gem_path, p)
+            end
+          }
+        }.flatten
+      else
+        []
+      end.freeze
+
     def self.retrieve_gem_and_system_load_path
-      gem_paths = Gem::Specification.latest_specs(true).map { |s|
-        s.require_paths.map { |p|
-          if absolute_path?(p)
-            p
-          else
-            File.join(s.full_gem_path, p)
-          end
-        }
-      }.flatten if defined?(Gem::Specification)
-      (gem_paths.to_a | $LOAD_PATH).sort
+      candidates = (GEM_PATHS | $LOAD_PATH)
+      candidates.map do |p|
+        if p.respond_to?(:to_path)
+          p.to_path
+        else
+          String(p) rescue nil
+        end
+      end.compact.sort
     end
 
     def self.retrieve_files_to_require_from_load_path
@@ -142,10 +173,10 @@ module IRB
         receiver = $1
         message = $3
 
-        candidates = String.instance_methods.collect{|m| m.to_s}
         if doc_namespace
           "String.#{message}"
         else
+          candidates = String.instance_methods.collect{|m| m.to_s}
           select_message(receiver, message, candidates)
         end
 
@@ -154,10 +185,10 @@ module IRB
         receiver = $1
         message = $2
 
-        candidates = Regexp.instance_methods.collect{|m| m.to_s}
         if doc_namespace
           "Regexp.#{message}"
         else
+          candidates = Regexp.instance_methods.collect{|m| m.to_s}
           select_message(receiver, message, candidates)
         end
 
@@ -166,10 +197,10 @@ module IRB
         receiver = $1
         message = $2
 
-        candidates = Array.instance_methods.collect{|m| m.to_s}
         if doc_namespace
           "Array.#{message}"
         else
+          candidates = Array.instance_methods.collect{|m| m.to_s}
           select_message(receiver, message, candidates)
         end
 
@@ -178,29 +209,33 @@ module IRB
         receiver = $1
         message = $2
 
-        proc_candidates = Proc.instance_methods.collect{|m| m.to_s}
-        hash_candidates = Hash.instance_methods.collect{|m| m.to_s}
         if doc_namespace
           ["Proc.#{message}", "Hash.#{message}"]
         else
+          proc_candidates = Proc.instance_methods.collect{|m| m.to_s}
+          hash_candidates = Hash.instance_methods.collect{|m| m.to_s}
           select_message(receiver, message, proc_candidates | hash_candidates)
         end
 
       when /^(:[^:.]*)$/
         # Symbol
-        return nil if doc_namespace
-        sym = $1
-        candidates = Symbol.all_symbols.collect do |s|
-          ":" + s.id2name.encode(Encoding.default_external)
-        rescue EncodingError
-          # ignore
+        if doc_namespace
+          nil
+        else
+          sym = $1
+          candidates = Symbol.all_symbols.collect do |s|
+            ":" + s.id2name.encode(Encoding.default_external)
+          rescue EncodingError
+            # ignore
+          end
+          candidates.grep(/^#{Regexp.quote(sym)}/)
         end
-        candidates.grep(/^#{Regexp.quote(sym)}/)
-
       when /^::([A-Z][^:\.\(\)]*)$/
         # Absolute Constant or class methods
         receiver = $1
+
         candidates = Object.constants.collect{|m| m.to_s}
+
         if doc_namespace
           candidates.find { |i| i == receiver }
         else
@@ -211,16 +246,18 @@ module IRB
         # Constant or class methods
         receiver = $1
         message = $2
-        begin
-          candidates = eval("#{receiver}.constants.collect{|m| m.to_s}", bind)
-          candidates |= eval("#{receiver}.methods.collect{|m| m.to_s}", bind)
-        rescue Exception
-          candidates = []
-        end
+
         if doc_namespace
           "#{receiver}::#{message}"
         else
-          select_message(receiver, message, candidates, "::")
+          begin
+            candidates = eval("#{receiver}.constants.collect{|m| m.to_s}", bind)
+            candidates |= eval("#{receiver}.methods.collect{|m| m.to_s}", bind)
+          rescue Exception
+            candidates = []
+          end
+
+          select_message(receiver, message, candidates.sort, "::")
         end
 
       when /^(:[^:.]+)(\.|::)([^.]*)$/
@@ -229,10 +266,10 @@ module IRB
         sep = $2
         message = $3
 
-        candidates = Symbol.instance_methods.collect{|m| m.to_s}
         if doc_namespace
           "Symbol.#{message}"
         else
+          candidates = Symbol.instance_methods.collect{|m| m.to_s}
           select_message(receiver, message, candidates, sep)
         end
 
@@ -244,6 +281,7 @@ module IRB
 
         begin
           instance = eval(receiver, bind)
+
           if doc_namespace
             "#{instance.class.name}.#{message}"
           else
@@ -254,7 +292,7 @@ module IRB
           if doc_namespace
             nil
           else
-            candidates = []
+            []
           end
         end
 
@@ -276,7 +314,7 @@ module IRB
           if doc_namespace
             nil
           else
-            candidates = []
+            []
           end
         end
 
@@ -284,6 +322,7 @@ module IRB
         # global var
         gvar = $1
         all_gvars = global_variables.collect{|m| m.to_s}
+
         if doc_namespace
           all_gvars.find{ |i| i == gvar }
         else
@@ -296,10 +335,10 @@ module IRB
         sep = $2
         message = $3
 
-        gv = eval("global_variables", bind).collect{|m| m.to_s}.push("true", "false", "nil")
-        lv = eval("local_variables", bind).collect{|m| m.to_s}
-        iv = eval("instance_variables", bind).collect{|m| m.to_s}
-        cv = eval("self.class.constants", bind).collect{|m| m.to_s}
+        gv = bind.eval_global_variables.collect{|m| m.to_s}.push("true", "false", "nil")
+        lv = bind.local_variables.collect{|m| m.to_s}
+        iv = bind.eval_instance_variables.collect{|m| m.to_s}
+        cv = bind.eval_class_constants.collect{|m| m.to_s}
 
         if (gv | lv | iv | cv).include?(receiver) or /^[A-Z]/ =~ receiver && /\./ !~ receiver
           # foo.func and foo is var. OR
@@ -322,11 +361,13 @@ module IRB
           to_ignore = ignored_modules
           ObjectSpace.each_object(Module){|m|
             next if (to_ignore.include?(m) rescue true)
+            next unless m.respond_to?(:instance_methods) # JRuby has modules that represent java packages. They don't include many common ruby methods
             candidates.concat m.instance_methods(false).collect{|x| x.to_s}
           }
           candidates.sort!
           candidates.uniq!
         end
+
         if doc_namespace
           rec_class = rec.is_a?(Module) ? rec : rec.class
           "#{rec_class.name}#{sep}#{candidates.find{ |i| i == message }}"
@@ -341,27 +382,28 @@ module IRB
         message = $1
 
         candidates = String.instance_methods(true).collect{|m| m.to_s}
+
         if doc_namespace
           "String.#{candidates.find{ |i| i == message }}"
         else
-          select_message(receiver, message, candidates)
+          select_message(receiver, message, candidates.sort)
         end
 
       else
         if doc_namespace
-          vars = eval("local_variables | instance_variables", bind).collect{|m| m.to_s}
+          vars = (bind.local_variables | bind.eval_instance_variables).collect{|m| m.to_s}
           perfect_match_var = vars.find{|m| m.to_s == input}
           if perfect_match_var
             eval("#{perfect_match_var}.class.name", bind)
           else
-            candidates = eval("methods | private_methods | local_variables | instance_variables | self.class.constants", bind).collect{|m| m.to_s}
+            candidates = (bind.eval_methods | bind.eval_private_methods | bind.local_variables | bind.eval_instance_variables | bind.eval_class_constants).collect{|m| m.to_s}
             candidates |= ReservedWords
             candidates.find{ |i| i == input }
           end
         else
-          candidates = eval("methods | private_methods | local_variables | instance_variables | self.class.constants", bind).collect{|m| m.to_s}
+          candidates = (bind.eval_methods | bind.eval_private_methods | bind.local_variables | bind.eval_instance_variables | bind.eval_class_constants).collect{|m| m.to_s}
           candidates |= ReservedWords
-          candidates.grep(/^#{Regexp.quote(input)}/)
+          candidates.grep(/^#{Regexp.quote(input)}/).sort
         end
       end
     end
diff --git a/lib/irb/context.rb b/lib/irb/context.rb
index 0a46c1b1d4..91fbb2fcf1 100644
--- a/lib/irb/context.rb
+++ b/lib/irb/context.rb
@@ -22,7 +22,7 @@ module IRB
     #
     # The optional +input_method+ argument:
     #
-    # +nil+::     uses stdin or Reidline or Readline
+    # +nil+::     uses stdin or Reline or Readline
     # +String+::  uses a File
     # +other+::   uses this as InputMethod
     def initialize(irb, workspace = nil, input_method = nil)
@@ -32,7 +32,7 @@ module IRB
       else
         @workspace = WorkSpace.new
       end
-      @thread = Thread.current if defined? Thread
+      @thread = Thread.current
 
       # copy of default configuration
       @ap_name = IRB.conf[:AP_NAME]
@@ -48,12 +48,19 @@ module IRB
       end
       if IRB.conf.has_key?(:USE_MULTILINE)
         @use_multiline = IRB.conf[:USE_MULTILINE]
-      elsif IRB.conf.has_key?(:USE_REIDLINE) # backward compatibility
+      elsif IRB.conf.has_key?(:USE_RELINE) # backward compatibility
+        warn <<~MSG.strip
+          USE_RELINE is deprecated, please use USE_MULTILINE instead.
+        MSG
+        @use_multiline = IRB.conf[:USE_RELINE]
+      elsif IRB.conf.has_key?(:USE_REIDLINE)
+        warn <<~MSG.strip
+          USE_REIDLINE is deprecated, please use USE_MULTILINE instead.
+        MSG
         @use_multiline = IRB.conf[:USE_REIDLINE]
       else
         @use_multiline = nil
       end
-      @use_colorize = IRB.conf[:USE_COLORIZE]
       @use_autocomplete = IRB.conf[:USE_AUTOCOMPLETE]
       @verbose = IRB.conf[:VERBOSE]
       @io = nil
@@ -84,14 +91,14 @@ module IRB
         when nil
           if STDIN.tty? && IRB.conf[:PROMPT_MODE] != :INF_RUBY && !use_singleline?
             # Both of multiline mode and singleline mode aren't specified.
-            @io = ReidlineInputMethod.new
+            @io = RelineInputMethod.new
           else
             @io = nil
           end
         when false
           @io = nil
         when true
-          @io = ReidlineInputMethod.new
+          @io = RelineInputMethod.new
         end
         unless @io
           case use_singleline?
@@ -116,6 +123,10 @@ module IRB
         end
         @io = StdioInputMethod.new unless @io
 
+      when '-'
+        @io = FileInputMethod.new($stdin)
+        @irb_name = '-'
+        @irb_path = '-'
       when String
         @io = FileInputMethod.new(input_method)
         @irb_name = File.basename(input_method)
@@ -141,6 +152,8 @@ module IRB
       if @newline_before_multiline_output.nil?
         @newline_before_multiline_output = true
       end
+
+      @command_aliases = IRB.conf[:COMMAND_ALIASES]
     end
 
     # The top-level workspace, see WorkSpace#main
@@ -157,7 +170,7 @@ module IRB
     # The current input method.
     #
     # Can be either StdioInputMethod, ReadlineInputMethod,
-    # ReidlineInputMethod, FileInputMethod or other specified when the
+    # RelineInputMethod, FileInputMethod or other specified when the
     # context is created. See ::new for more # information on +input_method+.
     attr_accessor :io
 
@@ -186,8 +199,6 @@ module IRB
     attr_reader :use_singleline
     # Whether colorization is enabled or not.
     #
-    # A copy of the default <code>IRB.conf[:USE_COLORIZE]</code>
-    attr_reader :use_colorize
     # A copy of the default <code>IRB.conf[:USE_AUTOCOMPLETE]</code>
     attr_reader :use_autocomplete
     # A copy of the default <code>IRB.conf[:INSPECT_MODE]</code>
@@ -320,20 +331,21 @@ module IRB
     # See IRB@Command+line+options for more command line options.
     attr_accessor :back_trace_limit
 
+    # User-defined IRB command aliases
+    attr_accessor :command_aliases
+
     # Alias for #use_multiline
     alias use_multiline? use_multiline
     # Alias for #use_singleline
     alias use_singleline? use_singleline
     # backward compatibility
-    alias use_reidline use_multiline
+    alias use_reline use_multiline
     # backward compatibility
-    alias use_reidline? use_multiline
+    alias use_reline? use_multiline
     # backward compatibility
     alias use_readline use_singleline
     # backward compatibility
     alias use_readline? use_singleline
-    # Alias for #use_colorize
-    alias use_colorize? use_colorize
     # Alias for #use_autocomplete
     alias use_autocomplete? use_autocomplete
     # Alias for #rc
@@ -347,7 +359,7 @@ module IRB
     # Returns whether messages are displayed or not.
     def verbose?
       if @verbose.nil?
-        if @io.kind_of?(ReidlineInputMethod)
+        if @io.kind_of?(RelineInputMethod)
           false
         elsif defined?(ReadlineInputMethod) && @io.kind_of?(ReadlineInputMethod)
           false
@@ -362,11 +374,11 @@ module IRB
     end
 
     # Whether #verbose? is +true+, and +input_method+ is either
-    # StdioInputMethod or ReidlineInputMethod or ReadlineInputMethod, see #io
+    # StdioInputMethod or RelineInputMethod or ReadlineInputMethod, see #io
     # for more information.
     def prompting?
       verbose? || (STDIN.tty? && @io.kind_of?(StdioInputMethod) ||
-                   @io.kind_of?(ReidlineInputMethod) ||
+                   @io.kind_of?(RelineInputMethod) ||
                    (defined?(ReadlineInputMethod) && @io.kind_of?(ReadlineInputMethod)))
     end
 
@@ -473,6 +485,20 @@ module IRB
         line = "begin ::Kernel.raise _; rescue _.class\n#{line}\n""end"
         @workspace.local_variable_set(:_, exception)
       end
+
+      # Transform a non-identifier alias (@, $) or keywords (next, break)
+      command, args = line.split(/\s/, 2)
+      if original = command_aliases[command.to_sym]
+        line = line.gsub(/\A#{Regexp.escape(command)}/, original.to_s)
+        command = original
+      end
+
+      # Hook command-specific transformation
+      command_class = ExtendCommandBundle.load_command(command)
+      if command_class&.respond_to?(:transform_args)
+        line = "#{command} #{command_class.transform_args(args)}"
+      end
+
       set_last_value(@workspace.evaluate(self, line, irb_path, line_no))
     end
 
@@ -514,5 +540,21 @@ module IRB
     end
     alias __to_s__ to_s
     alias to_s inspect
+
+    def local_variables # :nodoc:
+      workspace.binding.local_variables
+    end
+
+    # Return true if it's aliased from the argument and it's not an identifier.
+    def symbol_alias?(command)
+      return nil if command.match?(/\A\w+\z/)
+      command_aliases.key?(command.to_sym)
+    end
+
+    # Return true if the command supports transforming args
+    def transform_args?(command)
+      command = command_aliases.fetch(command.to_sym, command)
+      ExtendCommandBundle.load_command(command)&.respond_to?(:transform_args)
+    end
   end
 end
diff --git a/lib/irb/ext/multi-irb.rb b/lib/irb/ext/multi-irb.rb
index 74de1ecde5..e57d43a569 100644
--- a/lib/irb/ext/multi-irb.rb
+++ b/lib/irb/ext/multi-irb.rb
@@ -9,7 +9,6 @@
 #
 #
 #
-fail CantShiftToMultiIrbMode unless defined?(Thread)
 
 module IRB
   class JobManager
diff --git a/lib/irb/ext/save-history.rb b/lib/irb/ext/save-history.rb
index 7acaebe36a..9e7620545a 100644
--- a/lib/irb/ext/save-history.rb
+++ b/lib/irb/ext/save-history.rb
@@ -70,10 +70,10 @@ module IRB
       end
       history_file = IRB.rc_file("_history") unless history_file
       if File.exist?(history_file)
-        open(history_file, "r:#{IRB.conf[:LC_MESSAGES].encoding}") do |f|
+        File.open(history_file, "r:#{IRB.conf[:LC_MESSAGES].encoding}") do |f|
           f.each { |l|
             l = l.chomp
-            if self.class == ReidlineInputMethod and history.last&.end_with?("\\")
+            if self.class == RelineInputMethod and history.last&.end_with?("\\")
               history.last.delete_suffix!("\\")
               history.last << "\n" << l
             else
@@ -107,13 +107,13 @@ module IRB
           raise
         end
 
-        if File.exist?(history_file) && @loaded_history_mtime &&
+        if File.exist?(history_file) &&
            File.mtime(history_file) != @loaded_history_mtime
-          history = history[@loaded_history_lines..-1]
+          history = history[@loaded_history_lines..-1] if @loaded_history_lines
           append_history = true
         end
 
-        open(history_file, "#{append_history ? 'a' : 'w'}:#{IRB.conf[:LC_MESSAGES].encoding}", 0600) do |f|
+        File.open(history_file, (append_history ? 'a' : 'w'), 0o600, encoding: IRB.conf[:LC_MESSAGES]&.encoding) do |f|
           hist = history.map{ |l| l.split("\n").join("\\\n") }
           unless append_history
             begin
diff --git a/lib/irb/extend-command.rb b/lib/irb/extend-command.rb
index 7778a0d0ce..d0829a06c4 100644
--- a/lib/irb/extend-command.rb
+++ b/lib/irb/extend-command.rb
@@ -45,14 +45,15 @@ module IRB # :nodoc:
       [:quit, :irb_exit, OVERRIDE_PRIVATE_ONLY],
     ]
 
+
     @EXTEND_COMMANDS = [
       [
         :irb_current_working_workspace, :CurrentWorkingWorkspace, "cmd/chws",
+        [:cwws, NO_OVERRIDE],
+        [:pwws, NO_OVERRIDE],
         [:irb_print_working_workspace, OVERRIDE_ALL],
         [:irb_cwws, OVERRIDE_ALL],
         [:irb_pwws, OVERRIDE_ALL],
-        [:cwws, NO_OVERRIDE],
-        [:pwws, NO_OVERRIDE],
         [:irb_current_working_binding, OVERRIDE_ALL],
         [:irb_print_working_binding, OVERRIDE_ALL],
         [:irb_cwb, OVERRIDE_ALL],
@@ -60,10 +61,10 @@ module IRB # :nodoc:
       ],
       [
         :irb_change_workspace, :ChangeWorkspace, "cmd/chws",
-        [:irb_chws, OVERRIDE_ALL],
-        [:irb_cws, OVERRIDE_ALL],
         [:chws, NO_OVERRIDE],
         [:cws, NO_OVERRIDE],
+        [:irb_chws, OVERRIDE_ALL],
+        [:irb_cws, OVERRIDE_ALL],
         [:irb_change_binding, OVERRIDE_ALL],
         [:irb_cb, OVERRIDE_ALL],
         [:cb, NO_OVERRIDE],
@@ -77,16 +78,16 @@ module IRB # :nodoc:
       ],
       [
         :irb_push_workspace, :PushWorkspace, "cmd/pushws",
-        [:irb_pushws, OVERRIDE_ALL],
         [:pushws, NO_OVERRIDE],
+        [:irb_pushws, OVERRIDE_ALL],
         [:irb_push_binding, OVERRIDE_ALL],
         [:irb_pushb, OVERRIDE_ALL],
         [:pushb, NO_OVERRIDE],
       ],
       [
         :irb_pop_workspace, :PopWorkspace, "cmd/pushws",
-        [:irb_popws, OVERRIDE_ALL],
         [:popws, NO_OVERRIDE],
+        [:irb_popws, OVERRIDE_ALL],
         [:irb_pop_binding, OVERRIDE_ALL],
         [:irb_popb, OVERRIDE_ALL],
         [:popb, NO_OVERRIDE],
@@ -117,12 +118,56 @@ module IRB # :nodoc:
       ],
 
       [
+        :irb_debug, :Debug, "cmd/debug",
+        [:debug, NO_OVERRIDE],
+      ],
+      [
+        :irb_edit, :Edit, "cmd/edit",
+        [:edit, NO_OVERRIDE],
+      ],
+      [
+        :irb_break, :Break, "cmd/break",
+      ],
+      [
+        :irb_catch, :Catch, "cmd/catch",
+      ],
+      [
+        :irb_next, :Next, "cmd/next"
+      ],
+      [
+        :irb_delete, :Delete, "cmd/delete",
+        [:delete, NO_OVERRIDE],
+      ],
+      [
+        :irb_step, :Step, "cmd/step",
+        [:step, NO_OVERRIDE],
+      ],
+      [
+        :irb_continue, :Continue, "cmd/continue",
+        [:continue, NO_OVERRIDE],
+      ],
+      [
+        :irb_finish, :Finish, "cmd/finish",
+        [:finish, NO_OVERRIDE],
+      ],
+      [
+        :irb_backtrace, :Backtrace, "cmd/backtrace",
+        [:backtrace, NO_OVERRIDE],
+        [:bt, NO_OVERRIDE],
+      ],
+      [
+        :irb_debug_info, :Info, "cmd/info",
+        [:info, NO_OVERRIDE],
+      ],
+
+      [
         :irb_help, :Help, "cmd/help",
+        [:show_doc, NO_OVERRIDE],
         [:help, NO_OVERRIDE],
       ],
 
       [
-        :irb_info, :Info, "cmd/info"
+        :irb_info, :IrbInfo, "cmd/irb_info"
       ],
 
       [
@@ -144,24 +189,56 @@ module IRB # :nodoc:
         :irb_whereami, :Whereami, "cmd/whereami",
         [:whereami, NO_OVERRIDE],
       ],
-
+      [
+        :irb_show_cmds, :ShowCmds, "cmd/show_cmds",
+        [:show_cmds, NO_OVERRIDE],
+      ]
     ]
 
-    # Installs the default irb commands:
-    #
-    # +irb_current_working_workspace+::   Context#main
-    # +irb_change_workspace+::            Context#change_workspace
-    # +irb_workspaces+::                  Context#workspaces
-    # +irb_push_workspace+::              Context#push_workspace
-    # +irb_pop_workspace+::               Context#pop_workspace
-    # +irb_load+::                        #irb_load
-    # +irb_require+::                     #irb_require
-    # +irb_source+::                      IrbLoader#source_file
-    # +irb+::                             IRB.irb
-    # +irb_jobs+::                        JobManager
-    # +irb_fg+::                          JobManager#switch
-    # +irb_kill+::                        JobManager#kill
-    # +irb_help+::                        IRB@Command+line+options
+
+    @@commands = []
+
+    def self.all_commands_info
+      return @@commands unless @@commands.empty?
+      user_aliases = IRB.CurrentContext.command_aliases.each_with_object({}) do |(alias_name, target), result|
+        result[target] ||= []
+        result[target] << alias_name
+      end
+
+      @EXTEND_COMMANDS.each do |cmd_name, cmd_class, load_file, *aliases|
+        if !defined?(ExtendCommand) || !ExtendCommand.const_defined?(cmd_class, false)
+          require_relative load_file
+        end
+
+        klass = ExtendCommand.const_get(cmd_class, false)
+        aliases = aliases.map { |a| a.first }
+
+        if additional_aliases = user_aliases[cmd_name]
+          aliases += additional_aliases
+        end
+
+        display_name = aliases.shift || cmd_name
+        @@commands << { display_name: display_name, description: klass.description, category: klass.category }
+      end
+
+      @@commands
+    end
+
+    # Convert a command name to its implementation class if such command exists
+    def self.load_command(command)
+      command = command.to_sym
+      @EXTEND_COMMANDS.each do |cmd_name, cmd_class, load_file, *aliases|
+        next if cmd_name != command && aliases.all? { |alias_name, _| alias_name != command }
+
+        if !defined?(ExtendCommand) || !ExtendCommand.const_defined?(cmd_class, false)
+          require_relative load_file
+        end
+        return ExtendCommand.const_get(cmd_class, false)
+      end
+      nil
+    end
+
+    # Installs the default irb commands.
     def self.install_extend_commands
       for args in @EXTEND_COMMANDS
         def_extend_command(*args)
diff --git a/lib/irb/init.rb b/lib/irb/init.rb
index d2baee2017..55453cc8f7 100644
--- a/lib/irb/init.rb
+++ b/lib/irb/init.rb
@@ -44,8 +44,8 @@ module IRB # :nodoc:
     @CONF[:IRB_RC] = nil
 
     @CONF[:USE_SINGLELINE] = false unless defined?(ReadlineInputMethod)
-    @CONF[:USE_COLORIZE] = !ENV['NO_COLOR']
-    @CONF[:USE_AUTOCOMPLETE] = true
+    @CONF[:USE_COLORIZE] = (nc = ENV['NO_COLOR']).nil? || nc.empty?
+    @CONF[:USE_AUTOCOMPLETE] = ENV.fetch("IRB_USE_AUTOCOMPLETE", "true") != "false"
     @CONF[:INSPECT_MODE] = true
     @CONF[:USE_TRACER] = false
     @CONF[:USE_LOADER] = false
@@ -158,6 +158,16 @@ module IRB # :nodoc:
     @CONF[:LC_MESSAGES] = Locale.new
 
     @CONF[:AT_EXIT] = []
+
+    @CONF[:COMMAND_ALIASES] = {
+      # Symbol aliases
+      :'$' => :show_source,
+      :'@' => :whereami,
+      # Keyword aliases
+      :break => :irb_break,
+      :catch => :irb_catch,
+      :next => :irb_next,
+    }
   end
 
   def IRB.set_measure_callback(type = nil, arg = nil, &block)
@@ -255,8 +265,20 @@ module IRB # :nodoc:
       when "--nosingleline", "--noreadline"
         @CONF[:USE_SINGLELINE] = false
       when "--multiline", "--reidline"
+        if opt == "--reidline"
+          warn <<~MSG.strip
+            --reidline is deprecated, please use --multiline instead.
+          MSG
+        end
+
         @CONF[:USE_MULTILINE] = true
       when "--nomultiline", "--noreidline"
+        if opt == "--noreidline"
+          warn <<~MSG.strip
+            --noreidline is deprecated, please use --nomultiline instead.
+          MSG
+        end
+
         @CONF[:USE_MULTILINE] = false
       when /^--extra-doc-dir(?:=(.+))?/
         opt = $1 || argv.shift
@@ -289,6 +311,10 @@ module IRB # :nodoc:
         @CONF[:PROMPT_MODE] = prompt_mode
       when "--noprompt"
         @CONF[:PROMPT_MODE] = :NULL
+      when "--script"
+        noscript = false
+      when "--noscript"
+        noscript = true
       when "--inf-ruby-mode"
         @CONF[:PROMPT_MODE] = :INF_RUBY
       when "--sample-book-mode", "--simple-prompt"
@@ -309,16 +335,20 @@ module IRB # :nodoc:
         IRB.print_usage
         exit 0
       when "--"
-        if opt = argv.shift
+        if !noscript && (opt = argv.shift)
           @CONF[:SCRIPT] = opt
           $0 = opt
         end
         break
-      when /^-/
+      when /^-./
         fail UnrecognizedSwitch, opt
       else
-        @CONF[:SCRIPT] = opt
-        $0 = opt
+        if noscript
+          argv.unshift(opt)
+        else
+          @CONF[:SCRIPT] = opt
+          $0 = opt
+        end
         break
       end
     end
@@ -371,11 +401,9 @@ module IRB # :nodoc:
     end
     if xdg_config_home = ENV["XDG_CONFIG_HOME"]
       irb_home = File.join(xdg_config_home, "irb")
-      unless File.exist? irb_home
-        require 'fileutils'
-        FileUtils.mkdir_p irb_home
+      if File.directory?(irb_home)
+        yield proc{|rc| irb_home + "/irb#{rc}"}
       end
-      yield proc{|rc| irb_home + "/irb#{rc}"}
     end
     if home = ENV["HOME"]
       yield proc{|rc| home+"/.irb#{rc}"}
diff --git a/lib/irb/input-method.rb b/lib/irb/input-method.rb
index 64276e61be..9480573195 100644
--- a/lib/irb/input-method.rb
+++ b/lib/irb/input-method.rb
@@ -14,7 +14,6 @@ require_relative 'magic-file'
 require_relative 'completion'
 require 'io/console'
 require 'reline'
-require 'rdoc'
 
 module IRB
   STDIN_FILE_NAME = "(line)" # :nodoc:
@@ -39,7 +38,7 @@ module IRB
     public :gets
 
     def winsize
-      if instance_variable_defined?(:@stdout)
+      if instance_variable_defined?(:@stdout) && @stdout.tty?
         @stdout.winsize
       else
         [24, 80]
@@ -138,7 +137,7 @@ module IRB
     # Creates a new input method object
     def initialize(file)
       super
-      @io = IRB::MagicFile.open(file)
+      @io = file.is_a?(IO) ? file : IRB::MagicFile.open(file)
       @external_encoding = @io.external_encoding
     end
     # The file name of this input method, usually given during initialization.
@@ -262,7 +261,7 @@ module IRB
     end
   end
 
-  class ReidlineInputMethod < InputMethod
+  class RelineInputMethod < InputMethod
     include Reline
 
     # Creates a new input method object using Reline
@@ -287,7 +286,8 @@ module IRB
         if IRB.conf[:USE_COLORIZE]
           proc do |output, complete: |
             next unless IRB::Color.colorable?
-            IRB::Color.colorize_code(output, complete: complete)
+            lvars = IRB.CurrentContext&.local_variables || []
+            IRB::Color.colorize_code(output, complete: complete, local_variables: lvars)
           end
         else
           proc do |output|
@@ -296,8 +296,13 @@ module IRB
         end
       Reline.dig_perfect_match_proc = IRB::InputCompletor::PerfectMatchedProc
       Reline.autocompletion = IRB.conf[:USE_AUTOCOMPLETE]
+
       if IRB.conf[:USE_AUTOCOMPLETE]
-        Reline.add_dialog_proc(:show_doc, SHOW_DOC_DIALOG, Reline::DEFAULT_DIALOG_CONTEXT)
+        begin
+          require 'rdoc'
+          Reline.add_dialog_proc(:show_doc, SHOW_DOC_DIALOG, Reline::DEFAULT_DIALOG_CONTEXT)
+        rescue LoadError
+        end
       end
     end
 
@@ -456,7 +461,7 @@ module IRB
     # For debug message
     def inspect
       config = Reline::Config.new
-      str = "ReidlineInputMethod with Reline #{Reline::VERSION}"
+      str = "RelineInputMethod with Reline #{Reline::VERSION}"
       if config.respond_to?(:inputrc_path)
         inputrc_path = File.expand_path(config.inputrc_path)
       else
@@ -466,4 +471,13 @@ module IRB
       str
     end
   end
+
+  class ReidlineInputMethod < RelineInputMethod
+    def initialize
+      warn <<~MSG.strip
+        IRB::ReidlineInputMethod is deprecated, please use IRB::RelineInputMethod instead.
+      MSG
+      super
+    end
+  end
 end
diff --git a/lib/irb/inspector.rb b/lib/irb/inspector.rb
index 8c37c0f174..d8c0ba90cf 100644
--- a/lib/irb/inspector.rb
+++ b/lib/irb/inspector.rb
@@ -108,18 +108,10 @@ module IRB # :nodoc:
 
   Inspector.def_inspector([false, :to_s, :raw]){|v| v.to_s}
   Inspector.def_inspector([:p, :inspect]){|v|
-    result = v.inspect
-    if IRB.conf[:MAIN_CONTEXT]&.use_colorize? && Color.inspect_colorable?(v)
-      result = Color.colorize_code(result)
-    end
-    result
+    Color.colorize_code(v.inspect, colorable: Color.colorable? && Color.inspect_colorable?(v))
   }
   Inspector.def_inspector([true, :pp, :pretty_inspect], proc{require_relative "color_printer"}){|v|
-    if IRB.conf[:MAIN_CONTEXT]&.use_colorize?
-      IRB::ColorPrinter.pp(v, '').chomp
-    else
-      v.pretty_inspect.chomp
-    end
+    IRB::ColorPrinter.pp(v, '').chomp
   }
   Inspector.def_inspector([:yaml, :YAML], proc{require "yaml"}){|v|
     begin
diff --git a/lib/irb/irb.gemspec b/lib/irb/irb.gemspec
index 26d0fb018f..c3e8a4dc58 100644
--- a/lib/irb/irb.gemspec
+++ b/lib/irb/irb.gemspec
@@ -8,8 +8,8 @@ end
 Gem::Specification.new do |spec|
   spec.name          = "irb"
   spec.version       = IRB::VERSION
-  spec.authors       = ["Keiju ISHITSUKA"]
-  spec.email         = ["keiju@ruby-lang.org"]
+  spec.authors       = ["aycabta", "Keiju ISHITSUKA"]
+  spec.email         = ["aycabta@gmail.com", "keiju@ruby-lang.org"]
 
   spec.summary       = %q{Interactive Ruby command-line tool for REPL (Read Eval Print Loop).}
   spec.description   = %q{Interactive Ruby command-line tool for REPL (Read Eval Print Loop).}
@@ -34,7 +34,7 @@ Gem::Specification.new do |spec|
   spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
   spec.require_paths = ["lib"]
 
-  spec.required_ruby_version = Gem::Requirement.new(">= 2.5")
+  spec.required_ruby_version = Gem::Requirement.new(">= 2.6")
 
   spec.add_dependency "reline", ">= 0.3.0"
 end
diff --git a/lib/irb/lc/error.rb b/lib/irb/lc/error.rb
index b8a7fe5a0e..cb5c21cdb4 100644
--- a/lib/irb/lc/error.rb
+++ b/lib/irb/lc/error.rb
@@ -48,11 +48,6 @@ module IRB
       super("No such job(#{val}).")
     end
   end
-  class CantShiftToMultiIrbMode < StandardError
-    def initialize
-      super("Can't shift to multi irb mode.")
-    end
-  end
   class CantChangeBinding < StandardError
     def initialize(val)
       super("Can't change binding to (#{val}).")
diff --git a/lib/irb/lc/help-message b/lib/irb/lc/help-message
index 939dc38975..5b23f4c41e 100644
--- a/lib/irb/lc/help-message
+++ b/lib/irb/lc/help-message
@@ -1,61 +1,51 @@
-# -*- coding: utf-8 -*-
-#
-#   irb/lc/help-message.rb -
-#   	$Release Version: 0.9.6$
-#   	$Revision$
-#   	by Keiju ISHITSUKA(keiju@ruby-lang.org)
-#
-# --
-#
-#
-#
 Usage:  irb.rb [options] [programfile] [arguments]
-  -f                Suppress read of ~/.irbrc
-  -d                Set $DEBUG to true (same as `ruby -d')
-  -r load-module    Same as `ruby -r'
-  -I path           Specify $LOAD_PATH directory
-  -U                Same as `ruby -U`
-  -E enc            Same as `ruby -E`
-  -w                Same as `ruby -w`
-  -W[level=2]       Same as `ruby -W`
+  -f                Don't initialize from configuration file.
+  -d                Set $DEBUG and $VERBOSE to true (same as 'ruby -d').
+  -r load-module    Require load-module (same as 'ruby -r').
+  -I path           Specify $LOAD_PATH directory (same as 'ruby -I').
+  -U                Set external and internal encodings to UTF-8.
+  -E ex[:in]        Set default external (ex) and internal (in) encodings
+                    (same as 'ruby -E').
+  -w                Suppress warnings (same as 'ruby -w').
+  -W[level=2]       Set warning level: 0=silence, 1=medium, 2=verbose
+                    (same as 'ruby -W').
   --context-mode n  Set n[0-4] to method to create Binding Object,
-                    when new workspace was created
-  --extra-doc-dir   Add an extra doc dir for the doc dialog
-  --echo            Show result (default)
-  --noecho          Don't show result
+                    when new workspace was created.
+  --extra-doc-dir   Add an extra doc dir for the doc dialog.
+  --echo            Show result (default).
+  --noecho          Don't show result.
   --echo-on-assignment
-                    Show result on assignment
+                    Show result on assignment.
   --noecho-on-assignment
-                    Don't show result on assignment
+                    Don't show result on assignment.
   --truncate-echo-on-assignment
-                    Show truncated result on assignment (default)
-  --inspect         Use `inspect' for output
-  --noinspect       Don't use inspect for output
-  --multiline       Use multiline editor module
-  --nomultiline     Don't use multiline editor module
-  --singleline      Use singleline editor module
-  --nosingleline    Don't use singleline editor module
-  --colorize        Use colorization
-  --nocolorize      Don't use colorization
-  --autocomplete    Use autocompletion
-  --noautocomplete  Don't use autocompletion
-  --prompt prompt-mode/--prompt-mode prompt-mode
-                    Switch prompt mode. Pre-defined prompt modes are
-                    `default', `simple', `xmp' and `inf-ruby'
+                    Show truncated result on assignment (default).
+  --inspect         Use 'inspect' for output.
+  --noinspect       Don't use 'inspect' for output.
+  --multiline       Use multiline editor module.
+  --nomultiline     Don't use multiline editor module (default).
+  --singleline      Use single line editor module.
+  --nosingleline    Don't use single line editor module (default).
+  --colorize        Use color-highlighting (default).
+  --nocolorize      Don't use color-highlighting.
+  --autocomplete    Use auto-completion (default).
+  --noautocomplete  Don't use auto-completion.
+  --prompt prompt-mode, --prompt-mode prompt-mode
+                    Set prompt mode. Pre-defined prompt modes are:
+                    'default', 'classic', 'simple', 'inf-ruby', 'xmp', 'null'.
   --inf-ruby-mode   Use prompt appropriate for inf-ruby-mode on emacs.
                     Suppresses --multiline and --singleline.
-  --sample-book-mode/--simple-prompt
-                    Simple prompt mode
-  --noprompt        No prompt mode
+  --sample-book-mode, --simple-prompt
+                    Set prompt mode to 'simple'.
+  --noprompt        Don't output prompt.
+  --script          Script mode (default, treat first argument as script)
+  --noscript        No script mode (leave arguments in argv)
   --single-irb      Share self with sub-irb.
-  --tracer          Display trace for each execution of commands.
-  --back-trace-limit n
-                    Display backtrace top n and tail n. The default
-                    value is 16.
-  --verbose         Show details
-  --noverbose       Don't show details
-  -v, --version	    Print the version of irb
-  -h, --help        Print help
-  --                Separate options of irb from the list of command-line args
-
-# vim:fileencoding=utf-8
+  --tracer          Show stack trace for each command.
+  --back-trace-limit n[=16]
+                    Display backtrace top n and bottom n.
+  --verbose         Show details.
+  --noverbose       Don't show details.
+  -v, --version     Print the version of irb.
+  -h, --help        Print help.
+  --                Separate options of irb from the list of command-line args.
diff --git a/lib/irb/lc/ja/error.rb b/lib/irb/lc/ja/error.rb
index d7c181c02e..5e3622cbae 100644
--- a/lib/irb/lc/ja/error.rb
+++ b/lib/irb/lc/ja/error.rb
@@ -48,11 +48,6 @@ module IRB
       super("��よ��ジョブ(#{val})��り��ん.")
     end
   end
-  class CantShiftToMultiIrbMode < StandardError
-    def initialize
-      super("multi-irb mode�移れ��ん.")
-    end
-  end
   class CantChangeBinding < StandardError
     def initialize(val)
       super("�インディング(#{val})�変更����ん.")
diff --git a/lib/irb/lc/ja/help-message b/lib/irb/lc/ja/help-message
index 238535afb7..1c15d331ea 100644
--- a/lib/irb/lc/ja/help-message
+++ b/lib/irb/lc/ja/help-message
@@ -1,13 +1,3 @@
-# -*- coding: utf-8 -*-
-#   irb/lc/ja/help-message.rb -
-#   	$Release Version: 0.9.6$
-#   	$Revision$
-#   	by Keiju ISHITSUKA(keiju@ruby-lang.org)
-#
-# --
-#
-#
-#
 Usage:  irb.rb [options] [programfile] [arguments]
   -f		    ~/.irbrc を読�込���.
   -d                $DEBUG をtrue��る(ruby -d ���)
@@ -53,5 +43,3 @@ Usage:  irb.rb [options] [programfile] [arguments]
   -v, --version	    irb��ージョンを表示�る.
   -h, --help	    irb �ヘルプを表示�る.
   --		    以��コマンドライン引数をオプション���扱���.
-
-# vim:fileencoding=utf-8
diff --git a/lib/irb/ruby-lex.rb b/lib/irb/ruby-lex.rb
index 29862f5507..85b336fbe1 100644
--- a/lib/irb/ruby-lex.rb
+++ b/lib/irb/ruby-lex.rb
@@ -48,7 +48,7 @@ class RubyLex
   end
 
   # io functions
-  def set_input(io, p = nil, context: nil, &block)
+  def set_input(io, p = nil, context:, &block)
     @io = io
     if @io.respond_to?(:check_termination)
       @io.check_termination do |code|
@@ -65,6 +65,12 @@ class RubyLex
             false
           end
         else
+          # Accept any single-line input for symbol aliases or commands that transform args
+          command = code.split(/\s/, 2).first
+          if context.symbol_alias?(command) || context.transform_args?(command)
+            next true
+          end
+
           code.gsub!(/\s*\z/, '').concat("\n")
           ltype, indent, continue, code_block_open = check_state(code, context: context)
           if ltype or indent > 0 or continue or code_block_open
@@ -136,41 +142,37 @@ class RubyLex
     :on_param_error
   ]
 
+  def self.generate_local_variables_assign_code(local_variables)
+    "#{local_variables.join('=')}=nil;" unless local_variables.empty?
+  end
+
   def self.ripper_lex_without_warning(code, context: nil)
     verbose, $VERBOSE = $VERBOSE, nil
-    if context
-      lvars = context&.workspace&.binding&.local_variables
-      if lvars && !lvars.empty?
-        code = "#{lvars.join('=')}=nil\n#{code}"
-        line_no = 0
-      else
-        line_no = 1
-      end
+    lvars_code = generate_local_variables_assign_code(context&.local_variables || [])
+    if lvars_code
+      code = "#{lvars_code}\n#{code}"
+      line_no = 0
+    else
+      line_no = 1
     end
-    tokens = nil
+
     compile_with_errors_suppressed(code, line_no: line_no) do |inner_code, line_no|
       lexer = Ripper::Lexer.new(inner_code, '-', line_no)
       if lexer.respond_to?(:scan) # Ruby 2.7+
-        tokens = []
-        pos_to_index = {}
-        lexer.scan.each do |t|
+        lexer.scan.each_with_object([]) do |t, tokens|
           next if t.pos.first == 0
-          if pos_to_index.has_key?(t.pos)
-            index = pos_to_index[t.pos]
-            found_tk = tokens[index]
-            if ERROR_TOKENS.include?(found_tk.event) && !ERROR_TOKENS.include?(t.event)
-              tokens[index] = t
-            end
+          prev_tk = tokens.last
+          position_overlapped = prev_tk && t.pos[0] == prev_tk.pos[0] && t.pos[1] < prev_tk.pos[1] + prev_tk.tok.bytesize
+          if position_overlapped
+            tokens[-1] = t if ERROR_TOKENS.include?(prev_tk.event) && !ERROR_TOKENS.include?(t.event)
           else
-            pos_to_index[t.pos] = tokens.size
             tokens << t
           end
         end
       else
-        tokens = lexer.parse.reject { |it| it.pos.first == 0 }
+        lexer.parse.reject { |it| it.pos.first == 0 }.sort_by(&:pos)
       end
     end
-    tokens
   ensure
     $VERBOSE = verbose
   end
@@ -209,12 +211,7 @@ class RubyLex
           last_line = lines[line_index]&.byteslice(0, byte_pointer)
           code += last_line if last_line
           @tokens = self.class.ripper_lex_without_warning(code, context: context)
-          corresponding_token_depth = check_corresponding_token_depth(lines, line_index)
-          if corresponding_token_depth
-            corresponding_token_depth
-          else
-            nil
-          end
+          check_corresponding_token_depth(lines, line_index)
         end
       end
     end
@@ -225,6 +222,8 @@ class RubyLex
     ltype = process_literal_type(tokens)
     indent = process_nesting_level(tokens)
     continue = process_continue(tokens)
+    lvars_code = self.class.generate_local_variables_assign_code(context.local_variables)
+    code = "#{lvars_code}\n#{code}" if lvars_code
     code_block_open = check_code_block(code, tokens)
     [ltype, indent, continue, code_block_open]
   end
@@ -244,13 +243,13 @@ class RubyLex
     @code_block_open = false
   end
 
-  def each_top_level_statement
+  def each_top_level_statement(context)
     initialize_input
     catch(:TERM_INPUT) do
       loop do
         begin
           prompt
-          unless l = lex
+          unless l = lex(context)
             throw :TERM_INPUT if @line == ''
           else
             @line_no += l.count("\n")
@@ -280,18 +279,15 @@ class RubyLex
     end
   end
 
-  def lex
+  def lex(context)
     line = @input.call
     if @io.respond_to?(:check_termination)
       return line # multiline
     end
     code = @line + (line.nil? ? '' : line)
     code.gsub!(/\s*\z/, '').concat("\n")
-    @tokens = self.class.ripper_lex_without_warning(code)
-    @continue = process_continue
-    @code_block_open = check_code_block(code)
-    @indent = process_nesting_level
-    @ltype = process_literal_type
+    @tokens = self.class.ripper_lex_without_warning(code, context: context)
+    @ltype, @indent, @continue, @code_block_open = check_state(code, @tokens, context: context)
     line
   end
 
@@ -308,7 +304,7 @@ class RubyLex
       return true
     elsif tokens.size >= 1 and tokens[-1].event == :on_heredoc_end # "EOH\n"
       return false
-    elsif tokens.size >= 2 and defined?(Ripper::EXPR_BEG) and tokens[-2].state.anybits?(Ripper::EXPR_BEG | Ripper::EXPR_FNAME) and tokens[-2].tok !~ /\A\.\.\.?\z/
+    elsif tokens.size >= 2 and tokens[-2].state.anybits?(Ripper::EXPR_BEG | Ripper::EXPR_FNAME) and tokens[-2].tok !~ /\A\.\.\.?\z/
       # end of literal except for regexp
       # endless range at end of line is not a continue
       return true
@@ -389,21 +385,20 @@ class RubyLex
       $VERBOSE = verbose
     end
 
-    if defined?(Ripper::EXPR_BEG)
-      last_lex_state = tokens.last.state
-      if last_lex_state.allbits?(Ripper::EXPR_BEG)
-        return false
-      elsif last_lex_state.allbits?(Ripper::EXPR_DOT)
-        return true
-      elsif last_lex_state.allbits?(Ripper::EXPR_CLASS)
-        return true
-      elsif last_lex_state.allbits?(Ripper::EXPR_FNAME)
-        return true
-      elsif last_lex_state.allbits?(Ripper::EXPR_VALUE)
-        return true
-      elsif last_lex_state.allbits?(Ripper::EXPR_ARG)
-        return false
-      end
+    last_lex_state = tokens.last.state
+
+    if last_lex_state.allbits?(Ripper::EXPR_BEG)
+      return false
+    elsif last_lex_state.allbits?(Ripper::EXPR_DOT)
+      return true
+    elsif last_lex_state.allbits?(Ripper::EXPR_CLASS)
+      return true
+    elsif last_lex_state.allbits?(Ripper::EXPR_FNAME)
+      return true
+    elsif last_lex_state.allbits?(Ripper::EXPR_VALUE)
+      return true
+    elsif last_lex_state.allbits?(Ripper::EXPR_ARG)
+      return false
     end
 
     false
@@ -718,6 +713,7 @@ class RubyLex
     i = 0
     start_token = []
     end_type = []
+    pending_heredocs = []
     while i < tokens.size
       t = tokens[i]
       case t.event
@@ -741,18 +737,27 @@ class RubyLex
           end
         end
       when :on_backtick
-        start_token << t
-        end_type << :on_tstring_end
+        if t.state.allbits?(Ripper::EXPR_BEG)
+          start_token << t
+          end_type << :on_tstring_end
+        end
       when :on_qwords_beg, :on_words_beg, :on_qsymbols_beg, :on_symbols_beg
         start_token << t
         end_type << :on_tstring_end
       when :on_heredoc_beg
-        start_token << t
-        end_type << :on_heredoc_end
+        pending_heredocs << t
+      end
+
+      if pending_heredocs.any? && t.tok.include?("\n")
+        pending_heredocs.reverse_each do |t|
+          start_token << t
+          end_type << :on_heredoc_end
+        end
+        pending_heredocs = []
       end
       i += 1
     end
-    start_token.last.nil? ? nil : start_token.last
+    pending_heredocs.first || start_token.last
   end
 
   def process_literal_type(tokens = @tokens)
diff --git a/lib/irb/version.rb b/lib/irb/version.rb
index 481d14ffd2..d1c0e54fdc 100644
--- a/lib/irb/version.rb
+++ b/lib/irb/version.rb
@@ -11,7 +11,7 @@
 #
 
 module IRB # :nodoc:
-  VERSION = "1.4.1"
+  VERSION = "1.6.2"
   @RELEASE_VERSION = VERSION
-  @LAST_UPDATE_DATE = "2021-12-25"
+  @LAST_UPDATE_DATE = "2022-12-13"
 end
diff --git a/lib/irb/workspace.rb b/lib/irb/workspace.rb
index 2c4c40f348..e5ef52528a 100644
--- a/lib/irb/workspace.rb
+++ b/lib/irb/workspace.rb
@@ -158,27 +158,20 @@ EOF
         end
       end
 
-      # NOT using #use_colorize? of IRB.conf[:MAIN_CONTEXT] because this method may be called before IRB::Irb#run
-      use_colorize = IRB.conf.fetch(:USE_COLORIZE, true)
-      if use_colorize
-        lines = Color.colorize_code(code).lines
-      else
-        lines = code.lines
-      end
+      lines = Color.colorize_code(code).lines
       pos -= 1
 
       start_pos = [pos - 5, 0].max
       end_pos   = [pos + 5, lines.size - 1].min
 
-      if use_colorize
-        fmt = " %2s #{Color.colorize("%#{end_pos.to_s.length}d", [:BLUE, :BOLD])}: %s"
-      else
-        fmt = " %2s %#{end_pos.to_s.length}d: %s"
-      end
+      line_number_fmt = Color.colorize("%#{end_pos.to_s.length}d", [:BLUE, :BOLD])
+      fmt = " %2s #{line_number_fmt}: %s"
+
       body = (start_pos..end_pos).map do |current_pos|
         sprintf(fmt, pos == current_pos ? '=>' : '', current_pos + 1, lines[current_pos])
       end.join("")
-      "\nFrom: #{file} @ line #{pos + 1} :\n\n#{body}#{Color.clear if use_colorize}\n"
+
+      "\nFrom: #{file} @ line #{pos + 1} :\n\n#{body}#{Color.clear}\n"
     end
 
     def IRB.delete_caller
diff --git a/lib/logger.rb b/lib/logger.rb
index 7d55f62f30..7e4dacc911 100644
--- a/lib/logger.rb
+++ b/lib/logger.rb
@@ -19,216 +19,353 @@ require_relative 'logger/log_device'
 require_relative 'logger/severity'
 require_relative 'logger/errors'
 
-# == Description
+# \Class \Logger provides a simple but sophisticated logging utility that
+# you can use to create one or more
+# {event logs}[https://en.wikipedia.org/wiki/Logging_(software)#Event_logs]
+# for your program.
+# Each such log contains a chronological sequence of entries
+# that provides a record of the program's activities.
 #
-# The Logger class provides a simple but sophisticated logging utility that
-# you can use to output messages.
+# == About the Examples
 #
-# The messages have associated levels, such as +INFO+ or +ERROR+ that indicate
-# their importance.  You can then give the Logger a level, and only messages
-# at that level or higher will be printed.
+# All examples on this page assume that \Logger has been required:
 #
-# The levels are:
+#   require 'logger'
 #
-# +UNKNOWN+:: An unknown message that should always be logged.
-# +FATAL+:: An unhandleable error that results in a program crash.
-# +ERROR+:: A handleable error condition.
-# +WARN+::  A warning.
-# +INFO+::  Generic (useful) information about system operation.
-# +DEBUG+:: Low-level information for developers.
+# == Synopsis
 #
-# For instance, in a production system, you may have your Logger set to
-# +INFO+ or even +WARN+.
-# When you are developing the system, however, you probably
-# want to know about the program's internal state, and would set the Logger to
-# +DEBUG+.
+# Create a log with Logger.new:
 #
-# *Note*: Logger does not escape or sanitize any messages passed to it.
-# Developers should be aware of when potentially malicious data (user-input)
-# is passed to Logger, and manually escape the untrusted data:
+#   # Single log file.
+#   logger = Logger.new('t.log')
+#   # Size-based rotated logging: 3 10-megabyte files.
+#   logger = Logger.new('t.log', 3, 10485760)
+#   # Period-based rotated logging: daily (also allowed: 'weekly', 'monthly').
+#   logger = Logger.new('t.log', 'daily')
+#   # Log to an IO stream.
+#   logger = Logger.new($stdout)
 #
-#   logger.info("User-input: #{input.dump}")
-#   logger.info("User-input: %p" % input)
+# Add entries (level, message) with Logger#add:
 #
-# You can use #formatter= for escaping all data.
+#   logger.add(Logger::DEBUG, 'Maximal debugging info')
+#   logger.add(Logger::INFO, 'Non-error information')
+#   logger.add(Logger::WARN, 'Non-error warning')
+#   logger.add(Logger::ERROR, 'Non-fatal error')
+#   logger.add(Logger::FATAL, 'Fatal error')
+#   logger.add(Logger::UNKNOWN, 'Most severe')
 #
-#   original_formatter = Logger::Formatter.new
-#   logger.formatter = proc { |severity, datetime, progname, msg|
-#     original_formatter.call(severity, datetime, progname, msg.dump)
-#   }
-#   logger.info(input)
+# Close the log with Logger#close:
 #
-# === Example
+#   logger.close
 #
-# This creates a Logger that outputs to the standard output stream, with a
-# level of +WARN+:
+# == Entries
 #
-#   require 'logger'
+# You can add entries with method Logger#add:
+#
+#   logger.add(Logger::DEBUG, 'Maximal debugging info')
+#   logger.add(Logger::INFO, 'Non-error information')
+#   logger.add(Logger::WARN, 'Non-error warning')
+#   logger.add(Logger::ERROR, 'Non-fatal error')
+#   logger.add(Logger::FATAL, 'Fatal error')
+#   logger.add(Logger::UNKNOWN, 'Most severe')
+#
+# These shorthand methods also add entries:
+#
+#   logger.debug('Maximal debugging info')
+#   logger.info('Non-error information')
+#   logger.warn('Non-error warning')
+#   logger.error('Non-fatal error')
+#   logger.fatal('Fatal error')
+#   logger.unknown('Most severe')
+#
+# When you call any of these methods,
+# the entry may or may not be written to the log,
+# depending on the entry's severity and on the log level;
+# see {Log Level}[rdoc-ref:Logger@Log+Level]
+#
+# An entry always has:
+#
+# - A severity (the required argument to #add).
+# - An automatically created timestamp.
+#
+# And may also have:
+#
+# - A message.
+# - A program name.
+#
+# Example:
+#
+#   logger = Logger.new($stdout)
+#   logger.add(Logger::INFO, 'My message.', 'mung')
+#   # => I, [2022-05-07T17:21:46.536234 #20536]  INFO -- mung: My message.
+#
+# The default format for an entry is:
+#
+#   "%s, [%s #%d] %5s -- %s: %s\n"
+#
+# where the values to be formatted are:
+#
+# - \Severity (one letter).
+# - Timestamp.
+# - Process id.
+# - \Severity (word).
+# - Program name.
+# - Message.
+#
+# You can use a different entry format by:
+#
+# - Setting a custom format proc (affects following entries);
+#   see {formatter=}[Logger.html#attribute-i-formatter].
+# - Calling any of the methods above with a block
+#   (affects only the one entry).
+#   Doing so can have two benefits:
+#
+#   - Context: the block can evaluate the entire program context
+#     and create a context-dependent message.
+#   - Performance: the block is not evaluated unless the log level
+#     permits the entry actually to be written:
+#
+#       logger.error { my_slow_message_generator }
+#
+#     Contrast this with the string form, where the string is
+#     always evaluated, regardless of the log level:
+#
+#       logger.error("#{my_slow_message_generator}")
+#
+# === \Severity
+#
+# The severity of a log entry has two effects:
+#
+# - Determines whether the entry is selected for inclusion in the log;
+#   see {Log Level}[rdoc-ref:Logger@Log+Level].
+# - Indicates to any log reader (whether a person or a program)
+#   the relative importance of the entry.
+#
+# === Timestamp
 #
-#   logger = Logger.new(STDOUT)
-#   logger.level = Logger::WARN
+# The timestamp for a log entry is generated automatically
+# when the entry is created.
 #
-#   logger.debug("Created logger")
-#   logger.info("Program started")
-#   logger.warn("Nothing to do!")
+# The logged timestamp is formatted by method
+# {Time#strftime}[rdoc-ref:Time#strftime]
+# using this format string:
 #
-#   path = "a_non_existent_file"
+#   '%Y-%m-%dT%H:%M:%S.%6N'
 #
-#   begin
-#     File.foreach(path) do |line|
-#       unless line =~ /^(\w+) = (.*)$/
-#         logger.error("Line in wrong format: #{line.chomp}")
-#       end
-#     end
-#   rescue => err
-#     logger.fatal("Caught exception; exiting")
-#     logger.fatal(err)
-#   end
+# Example:
 #
-# Because the Logger's level is set to +WARN+, only the warning, error, and
-# fatal messages are recorded.  The debug and info messages are silently
-# discarded.
+#   logger = Logger.new($stdout)
+#   logger.add(Logger::INFO)
+#   # => I, [2022-05-07T17:04:32.318331 #20536]  INFO -- : nil
 #
-# === Features
+# You can set a different format using method #datetime_format=.
 #
-# There are several interesting features that Logger provides, like
-# auto-rolling of log files, setting the format of log messages, and
-# specifying a program name in conjunction with the message.  The next section
-# shows you how to achieve these things.
+# === Message
 #
+# The message is an optional argument to an entry method:
 #
-# == HOWTOs
+#   logger = Logger.new($stdout)
+#   logger.add(Logger::INFO, 'My message')
+#   # => I, [2022-05-07T18:15:37.647581 #20536]  INFO -- : My message
 #
-# === How to create a logger
+# For the default entry formatter, <tt>Logger::Formatter</tt>,
+# the message object may be:
 #
-# The options below give you various choices, in more or less increasing
-# complexity.
+# - A string: used as-is.
+# - An Exception: <tt>message.message</tt> is used.
+# - Anything else: <tt>message.inspect</tt> is used.
 #
-# 1. Create a logger which logs messages to STDERR/STDOUT.
+# *Note*: Logger::Formatter does not escape or sanitize
+# the message passed to it.
+# Developers should be aware that malicious data (user input)
+# may be in the message, and should explicitly escape untrusted data.
 #
-#      logger = Logger.new(STDERR)
-#      logger = Logger.new(STDOUT)
+# You can use a custom formatter to escape message data;
+# see the example at {formatter=}[Logger.html#attribute-i-formatter].
 #
-# 2. Create a logger for the file which has the specified name.
+# === Program Name
 #
-#      logger = Logger.new('logfile.log')
+# The program name is an optional argument to an entry method:
 #
-# 3. Create a logger for the specified file.
+#   logger = Logger.new($stdout)
+#   logger.add(Logger::INFO, 'My message', 'mung')
+#   # => I, [2022-05-07T18:17:38.084716 #20536]  INFO -- mung: My message
 #
-#      file = File.open('foo.log', File::WRONLY | File::APPEND)
-#      # To create new logfile, add File::CREAT like:
-#      # file = File.open('foo.log', File::WRONLY | File::APPEND | File::CREAT)
-#      logger = Logger.new(file)
+# The default program name for a new logger may be set in the call to
+# Logger.new via optional keyword argument +progname+:
 #
-# 4. Create a logger which ages the logfile once it reaches a certain size.
-#    Leave 10 "old" log files where each file is about 1,024,000 bytes.
+#   logger = Logger.new('t.log', progname: 'mung')
 #
-#      logger = Logger.new('foo.log', 10, 1024000)
+# The default program name for an existing logger may be set
+# by a call to method #progname=:
 #
-# 5. Create a logger which ages the logfile daily/weekly/monthly.
+#   logger.progname = 'mung'
 #
-#      logger = Logger.new('foo.log', 'daily')
-#      logger = Logger.new('foo.log', 'weekly')
-#      logger = Logger.new('foo.log', 'monthly')
+# The current program name may be retrieved with method
+# {progname}[Logger.html#attribute-i-progname]:
 #
-# === How to log a message
+#   logger.progname # => "mung"
 #
-# Notice the different methods (+fatal+, +error+, +info+) being used to log
-# messages of various levels?  Other methods in this family are +warn+ and
-# +debug+.  +add+ is used below to log a message of an arbitrary (perhaps
-# dynamic) level.
+# == Log Level
 #
-# 1. Message in a block.
+# The log level setting determines whether an entry is actually
+# written to the log, based on the entry's severity.
 #
-#      logger.fatal { "Argument 'foo' not given." }
+# These are the defined severities (least severe to most severe):
 #
-# 2. Message as a string.
+#   logger = Logger.new($stdout)
+#   logger.add(Logger::DEBUG, 'Maximal debugging info')
+#   # => D, [2022-05-07T17:57:41.776220 #20536] DEBUG -- : Maximal debugging info
+#   logger.add(Logger::INFO, 'Non-error information')
+#   # => I, [2022-05-07T17:59:14.349167 #20536]  INFO -- : Non-error information
+#   logger.add(Logger::WARN, 'Non-error warning')
+#   # => W, [2022-05-07T18:00:45.337538 #20536]  WARN -- : Non-error warning
+#   logger.add(Logger::ERROR, 'Non-fatal error')
+#   # => E, [2022-05-07T18:02:41.592912 #20536] ERROR -- : Non-fatal error
+#   logger.add(Logger::FATAL, 'Fatal error')
+#   # => F, [2022-05-07T18:05:24.703931 #20536] FATAL -- : Fatal error
+#   logger.add(Logger::UNKNOWN, 'Most severe')
+#   # => A, [2022-05-07T18:07:54.657491 #20536]   ANY -- : Most severe
 #
-#      logger.error "Argument #{@foo} mismatch."
+# The default initial level setting is Logger::DEBUG, the lowest level,
+# which means that all entries are to be written, regardless of severity:
 #
-# 3. With progname.
+#   logger = Logger.new($stdout)
+#   logger.level # => 0
+#   logger.add(0, "My message")
+#   # => D, [2022-05-11T15:10:59.773668 #20536] DEBUG -- : My message
 #
-#      logger.info('initialize') { "Initializing..." }
+# You can specify a different setting in a new logger
+# using keyword argument +level+ with an appropriate value:
 #
-# 4. With severity.
+#   logger = Logger.new($stdout, level: Logger::ERROR)
+#   logger = Logger.new($stdout, level: 'error')
+#   logger = Logger.new($stdout, level: :error)
+#   logger.level # => 3
 #
-#      logger.add(Logger::FATAL) { 'Fatal error!' }
+# With this level, entries with severity Logger::ERROR and higher
+# are written, while those with lower severities are not written:
 #
-# The block form allows you to create potentially complex log messages,
-# but to delay their evaluation until and unless the message is
-# logged.  For example, if we have the following:
+#   logger = Logger.new($stdout, level: Logger::ERROR)
+#   logger.add(3)
+#   # => E, [2022-05-11T15:17:20.933362 #20536] ERROR -- : nil
+#   logger.add(2) # Silent.
 #
-#     logger.debug { "This is a " + potentially + " expensive operation" }
+# You can set the log level for an existing logger
+# with method #level=:
 #
-# If the logger's level is +INFO+ or higher, no debug messages will be logged,
-# and the entire block will not even be evaluated.  Compare to this:
+#   logger.level = Logger::ERROR
 #
-#     logger.debug("This is a " + potentially + " expensive operation")
+# These shorthand methods also set the level:
 #
-# Here, the string concatenation is done every time, even if the log
-# level is not set to show the debug message.
+#   logger.debug! # => 0
+#   logger.info!  # => 1
+#   logger.warn!  # => 2
+#   logger.error! # => 3
+#   logger.fatal! # => 4
 #
-# === How to close a logger
+# You can retrieve the log level with method
+# {level}[Logger.html#attribute-i-level]:
 #
-#      logger.close
+#   logger.level = Logger::ERROR
+#   logger.level # => 3
 #
-# === Setting severity threshold
+# These methods return whether a given
+# level is to be written:
 #
-# 1. Original interface.
+#   logger.level = Logger::ERROR
+#   logger.debug? # => false
+#   logger.info?  # => false
+#   logger.warn?  # => false
+#   logger.error? # => true
+#   logger.fatal? # => true
 #
-#      logger.sev_threshold = Logger::WARN
+# == Log File Rotation
 #
-# 2. Log4r (somewhat) compatible interface.
+# By default, a log file is a single file that grows indefinitely
+# (until explicitly closed); there is no file rotation.
 #
-#      logger.level = Logger::INFO
+# To keep log files to a manageable size,
+# you can use _log_ _file_ _rotation_, which uses multiple log files:
 #
-#      # DEBUG < INFO < WARN < ERROR < FATAL < UNKNOWN
+# - Each log file has entries for a non-overlapping
+#   time interval.
+# - Only the most recent log file is open and active;
+#   the others are closed and inactive.
 #
-# 3. Symbol or String (case insensitive)
+# === Size-Based Rotation
 #
-#      logger.level = :info
-#      logger.level = 'INFO'
+# For size-based log file rotation, call Logger.new with:
 #
-#      # :debug < :info < :warn < :error < :fatal < :unknown
+# - Argument +logdev+ as a file path.
+# - Argument +shift_age+ with a positive integer:
+#   the number of log files to be in the rotation.
+# - Argument +shift_size+ as a positive integer:
+#   the maximum size (in bytes) of each log file;
+#   defaults to 1048576 (1 megabyte).
 #
-# 4. Constructor
+# Examples:
 #
-#      Logger.new(logdev, level: Logger::INFO)
-#      Logger.new(logdev, level: :info)
-#      Logger.new(logdev, level: 'INFO')
+#   logger = Logger.new('t.log', 3)           # Three 1-megabyte files.
+#   logger = Logger.new('t.log', 5, 10485760) # Five 10-megabyte files.
 #
-# == Format
+# For these examples, suppose:
 #
-# Log messages are rendered in the output stream in a certain format by
-# default.  The default format and a sample are shown below:
+#   logger = Logger.new('t.log', 3)
 #
-# Log format:
-#   SeverityID, [DateTime #pid] SeverityLabel -- ProgName: message
+# Logging begins in the new log file, +t.log+;
+# the log file is "full" and ready for rotation
+# when a new entry would cause its size to exceed +shift_size+.
 #
-# Log sample:
-#   I, [1999-03-03T02:34:24.895701 #19074]  INFO -- Main: info.
+# The first time +t.log+ is full:
 #
-# You may change the date and time format via #datetime_format=.
+# - +t.log+ is closed and renamed to +t.log.0+.
+# - A new file +t.log+ is opened.
 #
-#   logger.datetime_format = '%Y-%m-%d %H:%M:%S'
-#         # e.g. "2004-01-03 00:54:26"
+# The second time +t.log+ is full:
 #
-# or via the constructor.
+# - +t.log.0 is renamed as +t.log.1+.
+# - +t.log+ is closed and renamed to +t.log.0+.
+# - A new file +t.log+ is opened.
 #
-#   Logger.new(logdev, datetime_format: '%Y-%m-%d %H:%M:%S')
+# Each subsequent time that +t.log+ is full,
+# the log files are rotated:
 #
-# Or, you may change the overall format via the #formatter= method.
+# - +t.log.1+ is removed.
+# - +t.log.0 is renamed as +t.log.1+.
+# - +t.log+ is closed and renamed to +t.log.0+.
+# - A new file +t.log+ is opened.
 #
-#   logger.formatter = proc do |severity, datetime, progname, msg|
-#     "#{datetime}: #{msg}\n"
-#   end
-#   # e.g. "2005-09-22 08:51:08 +0900: hello world"
+# === Periodic Rotation
 #
-# or via the constructor.
+# For periodic rotation, call Logger.new with:
 #
-#   Logger.new(logdev, formatter: proc {|severity, datetime, progname, msg|
-#     "#{datetime}: #{msg}\n"
-#   })
+# - Argument +logdev+ as a file path.
+# - Argument +shift_age+ as a string period indicator.
+#
+# Examples:
+#
+#   logger = Logger.new('t.log', 'daily')   # Rotate log files daily.
+#   logger = Logger.new('t.log', 'weekly')  # Rotate log files weekly.
+#   logger = Logger.new('t.log', 'monthly') # Rotate log files monthly.
+#
+# Example:
+#
+#   logger = Logger.new('t.log', 'daily')
+#
+# When the given period expires:
+#
+# - The base log file, +t.log+ is closed and renamed
+#   with a date-based suffix such as +t.log.20220509+.
+# - A new log file +t.log+ is opened.
+# - Nothing is removed.
+#
+# The default format for the suffix is <tt>'%Y%m%d'</tt>,
+# which produces a suffix similar to the one above.
+# You can set a different format using create-time option
+# +shift_period_suffix+;
+# see details and suggestions at
+# {Time#strftime}[rdoc-ref:Time#strftime].
 #
 class Logger
   _, name, rev = %w$Id$
@@ -245,9 +382,18 @@ class Logger
   # Logging severity threshold (e.g. <tt>Logger::INFO</tt>).
   attr_reader :level
 
-  # Set logging severity threshold.
+  # Sets the log level; returns +severity+.
+  # See {Log Level}[rdoc-ref:Logger@Log+Level].
+  #
+  # Argument +severity+ may be an integer, a string, or a symbol:
+  #
+  #   logger.level = Logger::ERROR # => 3
+  #   logger.level = 3             # => 3
+  #   logger.level = 'error'       # => "error"
+  #   logger.level = :error        # => :error
+  #
+  # Logger#sev_threshold= is an alias for Logger#level=.
   #
-  # +severity+:: The Severity of the log message.
   def level=(severity)
     if severity.is_a?(Integer)
       @level = severity
@@ -274,109 +420,159 @@ class Logger
   # Program name to include in log messages.
   attr_accessor :progname
 
-  # Set date-time format.
+  # Sets the date-time format.
+  #
+  # Argument +datetime_format+ should be either of these:
+  #
+  # - A string suitable for use as a format for method
+  #   {Time#strftime}[rdoc-ref:Time#strftime].
+  # - +nil+: the logger uses <tt>'%Y-%m-%dT%H:%M:%S.%6N'</tt>.
   #
-  # +datetime_format+:: A string suitable for passing to +strftime+.
   def datetime_format=(datetime_format)
     @default_formatter.datetime_format = datetime_format
   end
 
-  # Returns the date format being used.  See #datetime_format=
+  # Returns the date-time format; see #datetime_format=.
+  #
   def datetime_format
     @default_formatter.datetime_format
   end
 
-  # Logging formatter, as a +Proc+ that will take four arguments and
-  # return the formatted message. The arguments are:
+  # Sets or retrieves the logger entry formatter proc.
   #
-  # +severity+:: The Severity of the log message.
-  # +time+:: A Time instance representing when the message was logged.
-  # +progname+:: The #progname configured, or passed to the logger method.
-  # +msg+:: The _Object_ the user passed to the log message; not necessarily a
-  #         String.
+  # When +formatter+ is +nil+, the logger uses Logger::Formatter.
+  #
+  # When +formatter+ is a proc, a new entry is formatted by the proc,
+  # which is called with four arguments:
+  #
+  # - +severity+: The severity of the entry.
+  # - +time+: A Time object representing the entry's timestamp.
+  # - +progname+: The program name for the entry.
+  # - +msg+: The message for the entry (string or string-convertible object).
+  #
+  # The proc should return a string containing the formatted entry.
+  #
+  # This custom formatter uses
+  # {String#dump}[rdoc-ref:String#dump]
+  # to escape the message string:
+  #
+  #   logger = Logger.new($stdout, progname: 'mung')
+  #   original_formatter = logger.formatter || Logger::Formatter.new
+  #   logger.formatter = proc { |severity, time, progname, msg|
+  #     original_formatter.call(severity, time, progname, msg.dump)
+  #   }
+  #   logger.add(Logger::INFO, "hello \n ''")
+  #   logger.add(Logger::INFO, "\f\x00\xff\\\"")
+  #
+  # Output:
+  #
+  #   I, [2022-05-13T13:16:29.637488 #8492]  INFO -- mung: "hello \n ''"
+  #   I, [2022-05-13T13:16:29.637610 #8492]  INFO -- mung: "\f\x00\xFF\\\""
   #
-  # The block should return an Object that can be written to the logging
-  # device via +write+.  The default formatter is used when no formatter is
-  # set.
   attr_accessor :formatter
 
   alias sev_threshold level
   alias sev_threshold= level=
 
-  # Returns +true+ if and only if the current severity level allows for the printing of
-  # +DEBUG+ messages.
+  # Returns +true+ if the log level allows entries with severity
+  # Logger::DEBUG to be written, +false+ otherwise.
+  # See {Log Level}[rdoc-ref:Logger@Log+Level].
+  #
   def debug?; level <= DEBUG; end
 
-  # Sets the severity to DEBUG.
+  # Sets the log level to Logger::DEBUG.
+  # See {Log Level}[rdoc-ref:Logger@Log+Level].
+  #
   def debug!; self.level = DEBUG; end
 
-  # Returns +true+ if and only if the current severity level allows for the printing of
-  # +INFO+ messages.
+  # Returns +true+ if the log level allows entries with severity
+  # Logger::INFO to be written, +false+ otherwise.
+  # See {Log Level}[rdoc-ref:Logger@Log+Level].
+  #
   def info?; level <= INFO; end
 
-  # Sets the severity to INFO.
+  # Sets the log level to Logger::INFO.
+  # See {Log Level}[rdoc-ref:Logger@Log+Level].
+  #
   def info!; self.level = INFO; end
 
-  # Returns +true+ if and only if the current severity level allows for the printing of
-  # +WARN+ messages.
+  # Returns +true+ if the log level allows entries with severity
+  # Logger::WARN to be written, +false+ otherwise.
+  # See {Log Level}[rdoc-ref:Logger@Log+Level].
+  #
   def warn?; level <= WARN; end
 
-  # Sets the severity to WARN.
+  # Sets the log level to Logger::WARN.
+  # See {Log Level}[rdoc-ref:Logger@Log+Level].
+  #
   def warn!; self.level = WARN; end
 
-  # Returns +true+ if and only if the current severity level allows for the printing of
-  # +ERROR+ messages.
+  # Returns +true+ if the log level allows entries with severity
+  # Logger::ERROR to be written, +false+ otherwise.
+  # See {Log Level}[rdoc-ref:Logger@Log+Level].
+  #
   def error?; level <= ERROR; end
 
-  # Sets the severity to ERROR.
+  # Sets the log level to Logger::ERROR.
+  # See {Log Level}[rdoc-ref:Logger@Log+Level].
+  #
   def error!; self.level = ERROR; end
 
-  # Returns +true+ if and only if the current severity level allows for the printing of
-  # +FATAL+ messages.
+  # Returns +true+ if the log level allows entries with severity
+  # Logger::FATAL to be written, +false+ otherwise.
+  # See {Log Level}[rdoc-ref:Logger@Log+Level].
+  #
   def fatal?; level <= FATAL; end
 
-  # Sets the severity to FATAL.
+  # Sets the log level to Logger::FATAL.
+  # See {Log Level}[rdoc-ref:Logger@Log+Level].
+  #
   def fatal!; self.level = FATAL; end
 
-  #
   # :call-seq:
-  #   Logger.new(logdev, shift_age = 0, shift_size = 1048576)
-  #   Logger.new(logdev, shift_age = 'weekly')
-  #   Logger.new(logdev, level: :info)
-  #   Logger.new(logdev, progname: 'progname')
-  #   Logger.new(logdev, formatter: formatter)
-  #   Logger.new(logdev, datetime_format: '%Y-%m-%d %H:%M:%S')
-  #
-  # === Args
-  #
-  # +logdev+::
-  #   The log device.  This is a filename (String), IO object (typically
-  #   +STDOUT+, +STDERR+, or an open file), +nil+ (it writes nothing) or
-  #   +File::NULL+ (same as +nil+).
-  # +shift_age+::
-  #   Number of old log files to keep, *or* frequency of rotation (+daily+,
-  #   +weekly+ or +monthly+). Default value is 0, which disables log file
-  #   rotation.
-  # +shift_size+::
-  #   Maximum logfile size in bytes (only applies when +shift_age+ is a positive
-  #   Integer). Defaults to +1048576+ (1MB).
-  # +level+::
-  #   Logging severity threshold. Default values is Logger::DEBUG.
-  # +progname+::
-  #   Program name to include in log messages. Default value is nil.
-  # +formatter+::
-  #   Logging formatter. Default values is an instance of Logger::Formatter.
-  # +datetime_format+::
-  #   Date and time format. Default value is '%Y-%m-%d %H:%M:%S'.
-  # +binmode+::
-  #   Use binary mode on the log device. Default value is false.
-  # +shift_period_suffix+::
-  #   The log file suffix format for +daily+, +weekly+ or +monthly+ rotation.
-  #   Default is '%Y%m%d'.
-  #
-  # === Description
-  #
-  # Create an instance.
+  #    Logger.new(logdev, shift_age = 0, shift_size = 1048576, **options)
+  #
+  # With the single argument +logdev+,
+  # returns a new logger with all default options:
+  #
+  #   Logger.new('t.log') # => #<Logger:0x000001e685dc6ac8>
+  #
+  # Argument +logdev+ must be one of:
+  #
+  # - A string filepath: entries are to be written
+  #   to the file at that path; if the file at that path exists,
+  #   new entries are appended.
+  # - An IO stream (typically +$stdout+, +$stderr+. or an open file):
+  #   entries are to be written to the given stream.
+  # - +nil+ or +File::NULL+: no entries are to be written.
+  #
+  # Examples:
+  #
+  #   Logger.new('t.log')
+  #   Logger.new($stdout)
+  #
+  # The keyword options are:
+  #
+  # - +level+: sets the log level; default value is Logger::DEBUG.
+  #   See {Log Level}[rdoc-ref:Logger@Log+Level]:
+  #
+  #     Logger.new('t.log', level: Logger::ERROR)
+  #
+  # - +progname+: sets the default program name; default is +nil+.
+  #   See {Program Name}[rdoc-ref:Logger@Program+Name]:
+  #
+  #     Logger.new('t.log', progname: 'mung')
+  #
+  # - +formatter+: sets the entry formatter; default is +nil+.
+  #   See {formatter=}[Logger.html#attribute-i-formatter].
+  # - +datetime_format+: sets the format for entry timestamp;
+  #   default is +nil+.
+  #   See #datetime_format=.
+  # - +binmode+: sets whether the logger writes in binary mode;
+  #   default is +false+.
+  # - +shift_period_suffix+: sets the format for the filename suffix
+  #   for periodic log file rotation; default is <tt>'%Y%m%d'</tt>.
+  #   See {Periodic Rotation}[rdoc-ref:Logger@Periodic+Rotation].
   #
   def initialize(logdev, shift_age = 0, shift_size = 1048576, level: DEBUG,
                  progname: nil, formatter: nil, datetime_format: nil,
@@ -395,67 +591,60 @@ class Logger
     end
   end
 
-  #
-  # :call-seq:
-  #   Logger#reopen
-  #   Logger#reopen(logdev)
-  #
-  # === Args
-  #
-  # +logdev+::
-  #   The log device.  This is a filename (String) or IO object (typically
-  #   +STDOUT+, +STDERR+, or an open file).  reopen the same filename if
-  #   it is +nil+, do nothing for IO.  Default is +nil+.
-  #
-  # === Description
-  #
-  # Reopen a log device.
+  # Sets the logger's output stream:
+  #
+  # - If +logdev+ is +nil+, reopens the current output stream.
+  # - If +logdev+ is a filepath, opens the indicated file for append.
+  # - If +logdev+ is an IO stream
+  #   (usually <tt>$stdout</tt>, <tt>$stderr</tt>, or an open File object),
+  #   opens the stream for append.
+  #
+  # Example:
+  #
+  #   logger = Logger.new('t.log')
+  #   logger.add(Logger::ERROR, 'one')
+  #   logger.close
+  #   logger.add(Logger::ERROR, 'two') # Prints 'log writing failed. closed stream'
+  #   logger.reopen
+  #   logger.add(Logger::ERROR, 'three')
+  #   logger.close
+  #   File.readlines('t.log')
+  #   # =>
+  #   # ["# Logfile created on 2022-05-12 14:21:19 -0500 by logger.rb/v1.5.0\n",
+  #   #  "E, [2022-05-12T14:21:27.596726 #22428] ERROR -- : one\n",
+  #   #  "E, [2022-05-12T14:23:05.847241 #22428] ERROR -- : three\n"]
   #
   def reopen(logdev = nil)
     @logdev&.reopen(logdev)
     self
   end
 
+  # Creates a log entry, which may or may not be written to the log,
+  # depending on the entry's severity and on the log level.
+  # See {Log Level}[rdoc-ref:Logger@Log+Level]
+  # and {Entries}[rdoc-ref:Logger@Entries] for details.
   #
-  # :call-seq:
-  #   Logger#add(severity, message = nil, progname = nil) { ... }
-  #
-  # === Args
-  #
-  # +severity+::
-  #   Severity.  Constants are defined in Logger namespace: +DEBUG+, +INFO+,
-  #   +WARN+, +ERROR+, +FATAL+, or +UNKNOWN+.
-  # +message+::
-  #   The log message.  A String or Exception.
-  # +progname+::
-  #   Program name string.  Can be omitted.  Treated as a message if no
-  #   +message+ and +block+ are given.
-  # +block+::
-  #   Can be omitted.  Called to get a message string if +message+ is nil.
-  #
-  # === Return
-  #
-  # When the given severity is not high enough (for this particular logger),
-  # log no message, and return +true+.
+  # Examples:
   #
-  # === Description
+  #   logger = Logger.new($stdout, progname: 'mung')
+  #   logger.add(Logger::INFO)
+  #   logger.add(Logger::ERROR, 'No good')
+  #   logger.add(Logger::ERROR, 'No good', 'gnum')
   #
-  # Log a message if the given severity is high enough.  This is the generic
-  # logging method.  Users will be more inclined to use #debug, #info, #warn,
-  # #error, and #fatal.
+  # Output:
   #
-  # <b>Message format</b>: +message+ can be any object, but it has to be
-  # converted to a String in order to log it.  Generally, +inspect+ is used
-  # if the given object is not a String.
-  # A special case is an +Exception+ object, which will be printed in detail,
-  # including message, class, and backtrace.  See #msg2str for the
-  # implementation if required.
+  #   I, [2022-05-12T16:25:31.469726 #36328]  INFO -- mung: mung
+  #   E, [2022-05-12T16:25:55.349414 #36328] ERROR -- mung: No good
+  #   E, [2022-05-12T16:26:35.841134 #36328] ERROR -- gnum: No good
   #
-  # === Bugs
+  # These convenience methods have implicit severity:
   #
-  # * Logfile is not locked.
-  # * Append open does not need to lock file.
-  # * If the OS supports multi I/O, records possibly may be mixed.
+  # - #debug.
+  # - #info.
+  # - #warn.
+  # - #error.
+  # - #fatal.
+  # - #unknown.
   #
   def add(severity, message = nil, progname = nil)
     severity ||= UNKNOWN
@@ -479,104 +668,71 @@ class Logger
   end
   alias log add
 
+  # Writes the given +msg+ to the log with no formatting;
+  # returns the number of characters written,
+  # or +nil+ if no log device exists:
   #
-  # Dump given message to the log device without any formatting.  If no log
-  # device exists, return +nil+.
+  #   logger = Logger.new($stdout)
+  #   logger << 'My message.' # => 10
+  #
+  # Output:
+  #
+  #   My message.
   #
   def <<(msg)
     @logdev&.write(msg)
   end
 
-  #
-  # Log a +DEBUG+ message.
-  #
-  # See #info for more information.
+  # Equivalent to calling #add with severity <tt>Logger::DEBUG</tt>.
   #
   def debug(progname = nil, &block)
     add(DEBUG, nil, progname, &block)
   end
 
-  #
-  # :call-seq:
-  #   info(message)
-  #   info(progname, &block)
-  #
-  # Log an +INFO+ message.
-  #
-  # +message+:: The message to log; does not need to be a String.
-  # +progname+:: In the block form, this is the #progname to use in the
-  #              log message.  The default can be set with #progname=.
-  # +block+:: Evaluates to the message to log.  This is not evaluated unless
-  #           the logger's level is sufficient to log the message.  This
-  #           allows you to create potentially expensive logging messages that
-  #           are only called when the logger is configured to show them.
-  #
-  # === Examples
-  #
-  #   logger.info("MainApp") { "Received connection from #{ip}" }
-  #   # ...
-  #   logger.info "Waiting for input from user"
-  #   # ...
-  #   logger.info { "User typed #{input}" }
-  #
-  # You'll probably stick to the second form above, unless you want to provide a
-  # program name (which you can do with #progname= as well).
-  #
-  # === Return
-  #
-  # See #add.
+  # Equivalent to calling #add with severity <tt>Logger::INFO</tt>.
   #
   def info(progname = nil, &block)
     add(INFO, nil, progname, &block)
   end
 
-  #
-  # Log a +WARN+ message.
-  #
-  # See #info for more information.
+  # Equivalent to calling #add with severity <tt>Logger::WARN</tt>.
   #
   def warn(progname = nil, &block)
     add(WARN, nil, progname, &block)
   end
 
-  #
-  # Log an +ERROR+ message.
-  #
-  # See #info for more information.
+  # Equivalent to calling #add with severity <tt>Logger::ERROR</tt>.
   #
   def error(progname = nil, &block)
     add(ERROR, nil, progname, &block)
   end
 
-  #
-  # Log a +FATAL+ message.
-  #
-  # See #info for more information.
+  # Equivalent to calling #add with severity <tt>Logger::FATAL</tt>.
   #
   def fatal(progname = nil, &block)
     add(FATAL, nil, progname, &block)
   end
 
-  #
-  # Log an +UNKNOWN+ message.  This will be printed no matter what the logger's
-  # level is.
-  #
-  # See #info for more information.
+  # Equivalent to calling #add with severity <tt>Logger::UNKNOWN</tt>.
   #
   def unknown(progname = nil, &block)
     add(UNKNOWN, nil, progname, &block)
   end
 
+  # Closes the logger; returns +nil+:
   #
-  # Close the logging device.
+  #   logger = Logger.new('t.log')
+  #   logger.close       # => nil
+  #   logger.info('foo') # Prints "log writing failed. closed stream"
   #
+  # Related: Logger#reopen.
   def close
     @logdev&.close
   end
 
 private
 
-  # Severity label for logging (max 5 chars).
+  # \Severity label for logging (max 5 chars).
   SEV_LABEL = %w(DEBUG INFO WARN ERROR FATAL ANY).freeze
 
   def format_severity(severity)
diff --git a/lib/logger/errors.rb b/lib/logger/errors.rb
index e8925e14ac..88581793f0 100644
--- a/lib/logger/errors.rb
+++ b/lib/logger/errors.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: true
 
-# not used after 1.2.7. just for compat.
 class Logger
+  # not used after 1.2.7. just for compat.
   class Error < RuntimeError # :nodoc:
   end
   class ShiftingError < Error # :nodoc:
diff --git a/lib/logger/formatter.rb b/lib/logger/formatter.rb
index 62bff7097a..c634dbf34d 100644
--- a/lib/logger/formatter.rb
+++ b/lib/logger/formatter.rb
@@ -3,7 +3,7 @@
 class Logger
   # Default formatter for log messages.
   class Formatter
-    Format = "%s, [%s #%d] %5s -- %s: %s\n"
+    Format = "%.1s, [%s #%d] %5s -- %s: %s\n"
     DatetimeFormat = "%Y-%m-%dT%H:%M:%S.%6N"
 
     attr_accessor :datetime_format
@@ -13,8 +13,7 @@ class Logger
     end
 
     def call(severity, time, progname, msg)
-      Format % [severity[0..0], format_datetime(time), Process.pid, severity, progname,
-        msg2str(msg)]
+      sprintf(Format, severity, format_datetime(time), Process.pid, severity, progname, msg2str(msg))
     end
 
   private
diff --git a/lib/logger/log_device.rb b/lib/logger/log_device.rb
index 8683328a5e..84277a2656 100644
--- a/lib/logger/log_device.rb
+++ b/lib/logger/log_device.rb
@@ -79,8 +79,10 @@ class Logger
     def set_dev(log)
       if log.respond_to?(:write) and log.respond_to?(:close)
         @dev = log
-        if log.respond_to?(:path)
-          @filename = log.path
+        if log.respond_to?(:path) and path = log.path
+          if File.exist?(path)
+            @filename = path
+          end
         end
       else
         @dev = open_logfile(log)
diff --git a/lib/logger/logger.gemspec b/lib/logger/logger.gemspec
index ccd4e70db7..d12db625d9 100644
--- a/lib/logger/logger.gemspec
+++ b/lib/logger/logger.gemspec
@@ -23,5 +23,4 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency "bundler", ">= 0"
   spec.add_development_dependency "rake", ">= 12.3.3"
   spec.add_development_dependency "test-unit"
-  spec.add_development_dependency "rdoc"
 end
diff --git a/lib/logger/version.rb b/lib/logger/version.rb
index ba845a9304..f85c72eed3 100644
--- a/lib/logger/version.rb
+++ b/lib/logger/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 class Logger
-  VERSION = "1.5.1"
+  VERSION = "1.5.3"
 end
diff --git a/lib/mkmf.rb b/lib/mkmf.rb
index 547a28577e..0fbc1cc2e5 100644
--- a/lib/mkmf.rb
+++ b/lib/mkmf.rb
@@ -67,7 +67,7 @@ module MakeMakefile
   C_EXT = %w[c m]
 
   ##
-  # Extensions for files complied with a C++ compiler
+  # Extensions for files compiled with a C++ compiler
 
   CXX_EXT = %w[cc mm cxx cpp]
   unless File.exist?(File.join(*File.split(__FILE__).tap {|d, b| b.swapcase}))
@@ -1762,7 +1762,7 @@ SRC
     hdr << "#endif\n"
     hdr = hdr.join("")
     log_src(hdr, "#{header} is")
-    unless (IO.read(header) == hdr rescue false)
+    unless (File.read(header) == hdr rescue false)
       File.open(header, "wb") do |hfile|
         hfile.write(hdr)
       end
@@ -1866,7 +1866,7 @@ SRC
     if pkgconfig = with_config("#{pkg}-config") and find_executable0(pkgconfig)
       # if and only if package specific config command is given
     elsif ($PKGCONFIG ||=
-           (pkgconfig = with_config("pkg-config", ("pkg-config" unless CROSS_COMPILING))) &&
+           (pkgconfig = with_config("pkg-config") {config_string("PKG_CONFIG") || "pkg-config"}) &&
            find_executable0(pkgconfig) && pkgconfig) and
         xsystem([*envs, $PKGCONFIG, "--exists", pkg])
       # default to pkg-config command
@@ -1964,13 +1964,14 @@ SRC
 
   def configuration(srcdir)
     mk = []
+    CONFIG['MKMF_VERBOSE'] ||= "0"
     vpath = $VPATH.dup
     CONFIG["hdrdir"] ||= $hdrdir
     mk << %{
 SHELL = /bin/sh
 
 # V=0 quiet, V=1 verbose.  other values don't work.
-V = 0
+V = #{CONFIG['MKMF_VERBOSE']}
 V0 = $(V:0=)
 Q1 = $(V:1=)
 Q = $(Q1:0=@)
@@ -2075,6 +2076,11 @@ sitearch = #{CONFIG['sitearch']}
 ruby_version = #{RbConfig::CONFIG['ruby_version']}
 ruby = #{$ruby.sub(%r[\A#{Regexp.quote(RbConfig::CONFIG['bindir'])}(?=/|\z)]) {'$(bindir)'}}
 RUBY = $(ruby#{sep})
+BUILTRUBY = #{if defined?($builtruby) && $builtruby
+    $builtruby
+  else
+    File.join('$(bindir)', CONFIG["RUBY_INSTALL_NAME"] + CONFIG['EXEEXT'])
+  end}
 ruby_headers = #{headers.join(' ')}
 
 RM = #{config_string('RM', &possible_command) || '$(RUBY) -run -e rm -- -f'}
@@ -2109,7 +2115,7 @@ preload = #{defined?($preload) && $preload ? $preload.join(' ') : ''}
   end
   # :startdoc:
 
-  # creates a stub Makefile.
+  # Creates a stub Makefile.
   #
   def dummy_makefile(srcdir)
     configuration(srcdir) << <<RULES << CLEANINGS
@@ -2280,7 +2286,7 @@ RULES
     RbConfig.expand(srcdir = srcprefix.dup)
 
     ext = ".#{$OBJEXT}"
-    orig_srcs = Dir[File.join(srcdir, "*.{#{SRC_EXT.join(%q{,})}}")].sort
+    orig_srcs = Dir[File.join(srcdir, "*.{#{SRC_EXT.join(%q{,})}}")]
     if not $objs
       srcs = $srcs || orig_srcs
       $objs = []
@@ -2290,7 +2296,7 @@ RULES
         h
       }
       unless objs.delete_if {|b, f| f.size == 1}.empty?
-        dups = objs.sort.map {|b, f|
+        dups = objs.map {|b, f|
           "#{b[/.*\./]}{#{f.collect {|n| n[/([^.]+)\z/]}.join(',')}}"
         }
         abort "source files duplication - #{dups.join(", ")}"
@@ -2372,11 +2378,19 @@ TIMESTAMP_DIR = #{$extout && $extmk ? '$(extout)/.timestamp' : '.'}
     install_dirs.each {|d| conf << ("%-14s= %s\n" % d) if /^[[:upper:]]/ =~ d[0]}
     sodir = $extout ? '$(TARGET_SO_DIR)' : '$(RUBYARCHDIR)'
     n = '$(TARGET_SO_DIR)$(TARGET)'
+    cleanobjs = ["$(OBJS)"]
+    if $extmk
+      %w[bc i s].each {|ex| cleanobjs << "$(OBJS:.#{$OBJEXT}=.#{ex})"}
+    end
+    if target
+      config_string('cleanobjs') {|t| cleanobjs << t.gsub(/\$\*/, "$(TARGET)#{deffile ? '-$(arch)': ''}")}
+    end
     conf << "\
 TARGET_SO_DIR =#{$extout ? " $(RUBYARCHDIR)/" : ''}
 TARGET_SO     = $(TARGET_SO_DIR)$(DLLIB)
 CLEANLIBS     = #{'$(TARGET_SO) ' if target}#{config_string('cleanlibs') {|t| t.gsub(/\$\*/) {n}}}
-CLEANOBJS     = *.#{$OBJEXT} #{config_string('cleanobjs') {|t| t.gsub(/\$\*/, "$(TARGET)#{deffile ? '-$(arch)': ''}")} if target} *.bak
+CLEANOBJS     = #{cleanobjs.join(' ')} *.bak
+TARGET_SO_DIR_TIMESTAMP = #{timestamp_file(sodir, target_prefix)}
 " #"
 
     conf = yield(conf) if block_given?
@@ -2410,7 +2424,7 @@ static: #{$extmk && !$static ? "all" : "$(STATIC_LIB)#{$extout ? " install-rb" :
     if target
       f = "$(DLLIB)"
       dest = "$(TARGET_SO)"
-      stamp = timestamp_file(dir, target_prefix)
+      stamp = '$(TARGET_SO_DIR_TIMESTAMP)'
       if $extout
         mfile.puts dest
         mfile.print "clean-so::\n"
@@ -2479,7 +2493,9 @@ static: #{$extmk && !$static ? "all" : "$(STATIC_LIB)#{$extout ? " install-rb" :
         end
       end
     end
-    dirs.unshift(sodir) if target and !dirs.include?(sodir)
+    if target and !dirs.include?(sodir)
+      mfile.print "$(TARGET_SO_DIR_TIMESTAMP):\n\t$(Q) $(MAKEDIRS) $(@D) #{sodir}\n\t$(Q) $(TOUCH) $@\n"
+    end
     dirs.each do |d|
       t = timestamp_file(d, target_prefix)
       mfile.print "#{t}:\n\t$(Q) $(MAKEDIRS) $(@D) #{d}\n\t$(Q) $(TOUCH) $@\n"
@@ -2523,7 +2539,7 @@ site-install-rb: install-rb
     mfile.print "$(TARGET_SO): "
     mfile.print "$(DEFFILE) " if makedef
     mfile.print "$(OBJS) Makefile"
-    mfile.print " #{timestamp_file(sodir, target_prefix)}" if $extout
+    mfile.print " $(TARGET_SO_DIR_TIMESTAMP)" if $extout
     mfile.print "\n"
     mfile.print "\t$(ECHO) linking shared-object #{target_prefix.sub(/\A\/(.*)/, '\1/')}$(DLLIB)\n"
     mfile.print "\t-$(Q)$(RM) $(@#{sep})\n"
@@ -2593,6 +2609,7 @@ site-install-rb: install-rb
     $INCFLAGS << " -I$(hdrdir)/ruby/backward" unless $extmk
     $INCFLAGS << " -I$(hdrdir) -I$(srcdir)"
     $DLDFLAGS = with_config("dldflags", arg_config("DLDFLAGS", config["DLDFLAGS"])).dup
+    config_string("ADDITIONAL_DLDFLAGS") {|flags| $DLDFLAGS << " " << flags} unless $extmk
     $LIBEXT = config['LIBEXT'].dup
     $OBJEXT = config["OBJEXT"].dup
     $EXEEXT = config["EXEEXT"].dup
diff --git a/lib/mutex_m.rb b/lib/mutex_m.rb
index abd0fc6add..17ec9924e4 100644
--- a/lib/mutex_m.rb
+++ b/lib/mutex_m.rb
@@ -40,7 +40,7 @@
 #
 module Mutex_m
 
-  VERSION = "0.1.1"
+  VERSION = "0.1.2"
   Ractor.make_shareable(VERSION) if defined?(Ractor)
 
   def Mutex_m.define_aliases(cl) # :nodoc:
diff --git a/lib/net/http.rb b/lib/net/http.rb
index 5e64e38665..387df4b8f4 100644
--- a/lib/net/http.rb
+++ b/lib/net/http.rb
@@ -1,4 +1,4 @@
-# frozen_string_literal: false
+# frozen_string_literal: true
 #
 # = net/http.rb
 #
@@ -32,373 +32,697 @@ module Net   #:nodoc:
   class HTTPHeaderSyntaxError < StandardError; end
   # :startdoc:
 
-  # == An HTTP client API for Ruby.
+  # \Class \Net::HTTP provides a rich library that implements the client
+  # in a client-server model that uses the \HTTP request-response protocol.
+  # For information about \HTTP, see:
+  #
+  # - {Hypertext Transfer Protocol}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol].
+  # - {Technical overview}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Technical_overview].
+  #
+  # == About the Examples
+  #
+  # :include: doc/net-http/examples.rdoc
+  #
+  # == Strategies
+  #
+  # - If you will make only a few GET requests,
+  #   consider using {OpenURI}[rdoc-ref:OpenURI].
+  # - If you will make only a few requests of all kinds,
+  #   consider using the various singleton convenience methods in this class.
+  #   Each of the following methods automatically starts and finishes
+  #   a {session}[rdoc-ref:Net::HTTP@Sessions] that sends a single request:
+  #
+  #     # Return string response body.
+  #     Net::HTTP.get(hostname, path)
+  #     Net::HTTP.get(uri)
+  #
+  #     # Write string response body to $stdout.
+  #     Net::HTTP.get_print(hostname, path)
+  #     Net::HTTP.get_print(uri)
+  #
+  #     # Return response as Net::HTTPResponse object.
+  #     Net::HTTP.get_response(hostname, path)
+  #     Net::HTTP.get_response(uri)
+  #     data = '{"title": "foo", "body": "bar", "userId": 1}'
+  #     Net::HTTP.post(uri, data)
+  #     params = {title: 'foo', body: 'bar', userId: 1}
+  #     Net::HTTP.post_form(uri, params)
+  #
+  # - If performance is important, consider using sessions, which lower request overhead.
+  #   This {session}[rdoc-ref:Net::HTTP@Sessions] has multiple requests for
+  #   {HTTP methods}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Request_methods]
+  #   and {WebDAV methods}[https://en.wikipedia.org/wiki/WebDAV#Implementation]:
+  #
+  #     Net::HTTP.start(hostname) do |http|
+  #       # Session started automatically before block execution.
+  #       http.get(path)
+  #       http.head(path)
+  #       body = 'Some text'
+  #       http.post(path, body)  # Can also have a block.
+  #       http.put(path, body)
+  #       http.delete(path)
+  #       http.options(path)
+  #       http.trace(path)
+  #       http.patch(path, body) # Can also have a block.
+  #       http.copy(path)
+  #       http.lock(path, body)
+  #       http.mkcol(path, body)
+  #       http.move(path)
+  #       http.propfind(path, body)
+  #       http.proppatch(path, body)
+  #       http.unlock(path, body)
+  #       # Session finished automatically at block exit.
+  #     end
   #
-  # Net::HTTP provides a rich library which can be used to build HTTP
-  # user-agents.  For more details about HTTP see
-  # [RFC2616](http://www.ietf.org/rfc/rfc2616.txt).
+  # The methods cited above are convenience methods that, via their few arguments,
+  # allow minimal control over the requests.
+  # For greater control, consider using {request objects}[rdoc-ref:Net::HTTPRequest].
   #
-  # Net::HTTP is designed to work closely with URI.  URI::HTTP#host,
-  # URI::HTTP#port and URI::HTTP#request_uri are designed to work with
-  # Net::HTTP.
+  # == URIs
   #
-  # If you are only performing a few GET requests you should try OpenURI.
+  # On the internet, a URI
+  # ({Universal Resource Identifier}[https://en.wikipedia.org/wiki/Uniform_Resource_Identifier])
+  # is a string that identifies a particular resource.
+  # It consists of some or all of: scheme, hostname, path, query, and fragment;
+  # see {URI syntax}[https://en.wikipedia.org/wiki/Uniform_Resource_Identifier#Syntax].
   #
-  # == Simple Examples
+  # A Ruby {URI::Generic}[rdoc-ref:URI::Generic] object
+  # represents an internet URI.
+  # It provides, among others, methods
+  # +scheme+, +hostname+, +path+, +query+, and +fragment+.
   #
-  # All examples assume you have loaded Net::HTTP with:
+  # === Schemes
   #
-  #   require 'net/http'
+  # An internet \URI has
+  # a {scheme}[https://en.wikipedia.org/wiki/List_of_URI_schemes].
   #
-  # This will also require 'uri' so you don't need to require it separately.
+  # The two schemes supported in \Net::HTTP are <tt>'https'</tt> and <tt>'http'</tt>:
   #
-  # The Net::HTTP methods in the following section do not persist
-  # connections.  They are not recommended if you are performing many HTTP
-  # requests.
+  #   uri.scheme                       # => "https"
+  #   URI('http://example.com').scheme # => "http"
   #
-  # === GET
+  # === Hostnames
   #
-  #   Net::HTTP.get('example.com', '/index.html') # => String
+  # A hostname identifies a server (host) to which requests may be sent:
   #
-  # === GET by URI
+  #   hostname = uri.hostname # => "jsonplaceholder.typicode.com"
+  #   Net::HTTP.start(hostname) do |http|
+  #     # Some HTTP stuff.
+  #   end
   #
-  #   uri = URI('http://example.com/index.html?count=10')
-  #   Net::HTTP.get(uri) # => String
+  # === Paths
   #
-  # === GET with Dynamic Parameters
+  # A host-specific path identifies a resource on the host:
   #
-  #   uri = URI('http://example.com/index.html')
-  #   params = { :limit => 10, :page => 3 }
-  #   uri.query = URI.encode_www_form(params)
+  #   _uri = uri.dup
+  #   _uri.path = '/todos/1'
+  #   hostname = _uri.hostname
+  #   path = _uri.path
+  #   Net::HTTP.get(hostname, path)
   #
-  #   res = Net::HTTP.get_response(uri)
-  #   puts res.body if res.is_a?(Net::HTTPSuccess)
+  # === Queries
   #
-  # === POST
+  # A host-specific query adds name/value pairs to the URI:
   #
-  #   uri = URI('http://www.example.com/search.cgi')
-  #   res = Net::HTTP.post_form(uri, 'q' => 'ruby', 'max' => '50')
-  #   puts res.body
+  #   _uri = uri.dup
+  #   params = {userId: 1, completed: false}
+  #   _uri.query = URI.encode_www_form(params)
+  #   _uri # => #<URI::HTTPS https://jsonplaceholder.typicode.com?userId=1&completed=false>
+  #   Net::HTTP.get(_uri)
   #
-  # === POST with Multiple Values
+  # === Fragments
   #
-  #   uri = URI('http://www.example.com/search.cgi')
-  #   res = Net::HTTP.post_form(uri, 'q' => ['ruby', 'perl'], 'max' => '50')
-  #   puts res.body
+  # A {URI fragment}[https://en.wikipedia.org/wiki/URI_fragment] has no effect
+  # in \Net::HTTP;
+  # the same data is returned, regardless of whether a fragment is included.
   #
-  # == How to use Net::HTTP
+  # == Request Headers
   #
-  # The following example code can be used as the basis of an HTTP user-agent
-  # which can perform a variety of request types using persistent
-  # connections.
+  # Request headers may be used to pass additional information to the host,
+  # similar to arguments passed in a method call;
+  # each header is a name/value pair.
   #
-  #   uri = URI('http://example.com/some_path?query=string')
+  # Each of the \Net::HTTP methods that sends a request to the host
+  # has optional argument +headers+,
+  # where the headers are expressed as a hash of field-name/value pairs:
   #
-  #   Net::HTTP.start(uri.host, uri.port) do |http|
-  #     request = Net::HTTP::Get.new uri
+  #   headers = {Accept: 'application/json', Connection: 'Keep-Alive'}
+  #   Net::HTTP.get(uri, headers)
   #
-  #     response = http.request request # Net::HTTPResponse object
-  #   end
+  # See lists of both standard request fields and common request fields at
+  # {Request Fields}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#Request_fields].
+  # A host may also accept other custom fields.
   #
-  # Net::HTTP::start immediately creates a connection to an HTTP server which
-  # is kept open for the duration of the block.  The connection will remain
-  # open for multiple requests in the block if the server indicates it
-  # supports persistent connections.
+  # == \HTTP Sessions
   #
-  # If you wish to re-use a connection across multiple HTTP requests without
-  # automatically closing it you can use ::new and then call #start and
-  # #finish manually.
+  # A _session_ is a connection between a server (host) and a client that:
   #
-  # The request types Net::HTTP supports are listed below in the section "HTTP
-  # Request Classes".
+  # - Is begun by instance method Net::HTTP#start.
+  # - May contain any number of requests.
+  # - Is ended by instance method Net::HTTP#finish.
   #
-  # For all the Net::HTTP request objects and shortcut request methods you may
-  # supply either a String for the request path or a URI from which Net::HTTP
-  # will extract the request path.
+  # See example sessions at {Strategies}[rdoc-ref:Net::HTTP@Strategies].
   #
-  # === Response Data
+  # === Session Using \Net::HTTP.start
   #
-  #   uri = URI('http://example.com/index.html')
-  #   res = Net::HTTP.get_response(uri)
+  # If you have many requests to make to a single host (and port),
+  # consider using singleton method Net::HTTP.start with a block;
+  # the method handles the session automatically by:
   #
-  #   # Headers
-  #   res['Set-Cookie']            # => String
-  #   res.get_fields('set-cookie') # => Array
-  #   res.to_hash['set-cookie']    # => Array
-  #   puts "Headers: #{res.to_hash.inspect}"
+  # - Calling #start before block execution.
+  # - Executing the block.
+  # - Calling #finish after block execution.
   #
-  #   # Status
-  #   puts res.code       # => '200'
-  #   puts res.message    # => 'OK'
-  #   puts res.class.name # => 'HTTPOK'
+  # In the block, you can use these instance methods,
+  # each of which that sends a single request:
   #
-  #   # Body
-  #   puts res.body
+  # - {HTTP methods}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Request_methods]:
   #
-  # === Following Redirection
+  #   - #get, #request_get: GET.
+  #   - #head, #request_head: HEAD.
+  #   - #post, #request_post: POST.
+  #   - #delete: DELETE.
+  #   - #options: OPTIONS.
+  #   - #trace: TRACE.
+  #   - #patch: PATCH.
   #
-  # Each Net::HTTPResponse object belongs to a class for its response code.
+  # - {WebDAV methods}[https://en.wikipedia.org/wiki/WebDAV#Implementation]:
   #
-  # For example, all 2XX responses are instances of a Net::HTTPSuccess
-  # subclass, a 3XX response is an instance of a Net::HTTPRedirection
-  # subclass and a 200 response is an instance of the Net::HTTPOK class.  For
-  # details of response classes, see the section "HTTP Response Classes"
-  # below.
+  #   - #copy: COPY.
+  #   - #lock: LOCK.
+  #   - #mkcol: MKCOL.
+  #   - #move: MOVE.
+  #   - #propfind: PROPFIND.
+  #   - #proppatch: PROPPATCH.
+  #   - #unlock: UNLOCK.
   #
-  # Using a case statement you can handle various types of responses properly:
+  # === Session Using \Net::HTTP.start and \Net::HTTP.finish
   #
-  #   def fetch(uri_str, limit = 10)
-  #     # You should choose a better exception.
-  #     raise ArgumentError, 'too many HTTP redirects' if limit == 0
+  # You can manage a session manually using methods #start and #finish:
   #
-  #     response = Net::HTTP.get_response(URI(uri_str))
+  #   http = Net::HTTP.new(hostname)
+  #   http.start
+  #   http.get('/todos/1')
+  #   http.get('/todos/2')
+  #   http.delete('/posts/1')
+  #   http.finish # Needed to free resources.
   #
-  #     case response
-  #     when Net::HTTPSuccess then
-  #       response
-  #     when Net::HTTPRedirection then
-  #       location = response['location']
-  #       warn "redirected to #{location}"
-  #       fetch(location, limit - 1)
-  #     else
-  #       response.value
-  #     end
-  #   end
+  # === Single-Request Session
   #
-  #   print fetch('http://www.ruby-lang.org')
+  # Certain convenience methods automatically handle a session by:
   #
-  # === POST
+  # - Creating an \HTTP object
+  # - Starting a session.
+  # - Sending a single request.
+  # - Finishing the session.
+  # - Destroying the object.
   #
-  # A POST can be made using the Net::HTTP::Post request class.  This example
-  # creates a URL encoded POST body:
+  # Such methods that send GET requests:
   #
-  #   uri = URI('http://www.example.com/todo.cgi')
-  #   req = Net::HTTP::Post.new(uri)
-  #   req.set_form_data('from' => '2005-01-01', 'to' => '2005-03-31')
+  # - ::get: Returns the string response body.
+  # - ::get_print: Writes the string response body to $stdout.
+  # - ::get_response: Returns a Net::HTTPResponse object.
   #
-  #   res = Net::HTTP.start(uri.hostname, uri.port) do |http|
-  #     http.request(req)
-  #   end
+  # Such methods that send POST requests:
   #
-  #   case res
-  #   when Net::HTTPSuccess, Net::HTTPRedirection
-  #     # OK
-  #   else
-  #     res.value
-  #   end
+  # - ::post: Posts data to the host.
+  # - ::post_form: Posts form data to the host.
   #
-  # To send multipart/form-data use Net::HTTPHeader#set_form:
+  # == \HTTP Requests and Responses
   #
-  #   req = Net::HTTP::Post.new(uri)
-  #   req.set_form([['upload', File.open('foo.bar')]], 'multipart/form-data')
+  # Many of the methods above are convenience methods,
+  # each of which sends a request and returns a string
+  # without directly using \Net::HTTPRequest and \Net::HTTPResponse objects.
   #
-  # Other requests that can contain a body such as PUT can be created in the
-  # same way using the corresponding request class (Net::HTTP::Put).
+  # You can, however, directly create a request object, send the request,
+  # and retrieve the response object; see:
   #
-  # === Setting Headers
+  # - Net::HTTPRequest.
+  # - Net::HTTPResponse.
   #
-  # The following example performs a conditional GET using the
-  # If-Modified-Since header.  If the files has not been modified since the
-  # time in the header a Not Modified response will be returned.  See RFC 2616
-  # section 9.3 for further details.
+  # == Following Redirection
   #
-  #   uri = URI('http://example.com/cached_response')
-  #   file = File.stat 'cached_response'
+  # Each returned response is an instance of a subclass of Net::HTTPResponse.
+  # See the {response class hierarchy}[rdoc-ref:Net::HTTPResponse@Response+Subclasses].
   #
-  #   req = Net::HTTP::Get.new(uri)
-  #   req['If-Modified-Since'] = file.mtime.rfc2822
+  # In particular, class Net::HTTPRedirection is the parent
+  # of all redirection classes.
+  # This allows you to craft a case statement to handle redirections properly:
   #
-  #   res = Net::HTTP.start(uri.hostname, uri.port) {|http|
-  #     http.request(req)
-  #   }
+  #   def fetch(uri, limit = 10)
+  #     # You should choose a better exception.
+  #     raise ArgumentError, 'Too many HTTP redirects' if limit == 0
+  #
+  #     res = Net::HTTP.get_response(URI(uri))
+  #     case res
+  #     when Net::HTTPSuccess     # Any success class.
+  #       res
+  #     when Net::HTTPRedirection # Any redirection class.
+  #       location = res['Location']
+  #       warn "Redirected to #{location}"
+  #       fetch(location, limit - 1)
+  #     else                      # Any other class.
+  #       res.value
+  #     end
+  #   end
   #
-  #   open 'cached_response', 'w' do |io|
-  #     io.write res.body
-  #   end if res.is_a?(Net::HTTPSuccess)
+  #   fetch(uri)
   #
-  # === Basic Authentication
+  # == Basic Authentication
   #
   # Basic authentication is performed according to
-  # [RFC2617](http://www.ietf.org/rfc/rfc2617.txt).
-  #
-  #   uri = URI('http://example.com/index.html?key=value')
+  # {RFC2617}[http://www.ietf.org/rfc/rfc2617.txt]:
   #
   #   req = Net::HTTP::Get.new(uri)
-  #   req.basic_auth 'user', 'pass'
-  #
-  #   res = Net::HTTP.start(uri.hostname, uri.port) {|http|
+  #   req.basic_auth('user', 'pass')
+  #   res = Net::HTTP.start(hostname) do |http|
   #     http.request(req)
-  #   }
-  #   puts res.body
+  #   end
   #
-  # === Streaming Response Bodies
+  # == Streaming Response Bodies
   #
-  # By default Net::HTTP reads an entire response into memory.  If you are
+  # By default \Net::HTTP reads an entire response into memory.  If you are
   # handling large files or wish to implement a progress bar you can instead
   # stream the body directly to an IO.
   #
-  #   uri = URI('http://example.com/large_file')
-  #
-  #   Net::HTTP.start(uri.host, uri.port) do |http|
-  #     request = Net::HTTP::Get.new uri
-  #
-  #     http.request request do |response|
-  #       open 'large_file', 'w' do |io|
-  #         response.read_body do |chunk|
-  #           io.write chunk
+  #   Net::HTTP.start(hostname) do |http|
+  #     req = Net::HTTP::Get.new(uri)
+  #     http.request(req) do |res|
+  #       open('t.tmp', 'w') do |f|
+  #         res.read_body do |chunk|
+  #           f.write chunk
   #         end
   #       end
   #     end
   #   end
   #
-  # === HTTPS
+  # == HTTPS
   #
-  # HTTPS is enabled for an HTTP connection by Net::HTTP#use_ssl=.
+  # HTTPS is enabled for an \HTTP connection by Net::HTTP#use_ssl=:
   #
-  #   uri = URI('https://secure.example.com/some_path?query=string')
-  #
-  #   Net::HTTP.start(uri.host, uri.port, :use_ssl => true) do |http|
-  #     request = Net::HTTP::Get.new uri
-  #     response = http.request request # Net::HTTPResponse object
+  #   Net::HTTP.start(hostname, :use_ssl => true) do |http|
+  #     req = Net::HTTP::Get.new(uri)
+  #     res = http.request(req)
   #   end
   #
-  # Or if you simply want to make a GET request, you may pass in an URI
-  # object that has an HTTPS URL. Net::HTTP automatically turns on TLS
-  # verification if the URI object has a 'https' URI scheme.
+  # Or if you simply want to make a GET request, you may pass in a URI
+  # object that has an \HTTPS URL. \Net::HTTP automatically turns on TLS
+  # verification if the URI object has a 'https' URI scheme:
+  #
+  #   uri # => #<URI::HTTPS https://jsonplaceholder.typicode.com/>
+  #   Net::HTTP.get(uri)
+  #
+  # == Proxy Server
+  #
+  # An \HTTP object can have
+  # a {proxy server}[https://en.wikipedia.org/wiki/Proxy_server].
+  #
+  # You can create an \HTTP object with a proxy server
+  # using method Net::HTTP.new or method Net::HTTP.start.
+  #
+  # The proxy may be defined either by argument +p_addr+
+  # or by environment variable <tt>'http_proxy'</tt>.
+  #
+  # === Proxy Using Argument +p_addr+ as a \String
+  #
+  # When argument +p_addr+ is a string hostname,
+  # the returned +http+ has the given host as its proxy:
+  #
+  #   http = Net::HTTP.new(hostname, nil, 'proxy.example')
+  #   http.proxy?          # => true
+  #   http.proxy_from_env? # => false
+  #   http.proxy_address   # => "proxy.example"
+  #   # These use default values.
+  #   http.proxy_port      # => 80
+  #   http.proxy_user      # => nil
+  #   http.proxy_pass      # => nil
   #
-  #   uri = URI('https://example.com/')
-  #   Net::HTTP.get(uri) # => String
+  # The port, username, and password for the proxy may also be given:
   #
-  # In previous versions of Ruby you would need to require 'net/https' to use
-  # HTTPS. This is no longer true.
+  #   http = Net::HTTP.new(hostname, nil, 'proxy.example', 8000, 'pname', 'ppass')
+  #   # => #<Net::HTTP jsonplaceholder.typicode.com:80 open=false>
+  #   http.proxy?          # => true
+  #   http.proxy_from_env? # => false
+  #   http.proxy_address   # => "proxy.example"
+  #   http.proxy_port      # => 8000
+  #   http.proxy_user      # => "pname"
+  #   http.proxy_pass      # => "ppass"
+  #
+  # === Proxy Using '<tt>ENV['http_proxy']</tt>'
+  #
+  # When environment variable <tt>'http_proxy'</tt>
+  # is set to a \URI string,
+  # the returned +http+ will have the server at that URI as its proxy;
+  # note that the \URI string must have a protocol
+  # such as <tt>'http'</tt> or <tt>'https'</tt>:
+  #
+  #   ENV['http_proxy'] = 'http://example.com'
+  #   http = Net::HTTP.new(hostname)
+  #   http.proxy?          # => true
+  #   http.proxy_from_env? # => true
+  #   http.proxy_address   # => "example.com"
+  #   # These use default values.
+  #   http.proxy_port      # => 80
+  #   http.proxy_user      # => nil
+  #   http.proxy_pass      # => nil
+  #
+  # The \URI string may include proxy username, password, and port number:
+  #
+  #   ENV['http_proxy'] = 'http://pname:ppass@example.com:8000'
+  #   http = Net::HTTP.new(hostname)
+  #   http.proxy?          # => true
+  #   http.proxy_from_env? # => true
+  #   http.proxy_address   # => "example.com"
+  #   http.proxy_port      # => 8000
+  #   http.proxy_user      # => "pname"
+  #   http.proxy_pass      # => "ppass"
+  #
+  # === Filtering Proxies
+  #
+  # With method Net::HTTP.new (but not Net::HTTP.start),
+  # you can use argument +p_no_proxy+ to filter proxies:
+  #
+  # - Reject a certain address:
+  #
+  #     http = Net::HTTP.new('example.com', nil, 'proxy.example', 8000, 'pname', 'ppass', 'proxy.example')
+  #     http.proxy_address # => nil
+  #
+  # - Reject certain domains or subdomains:
+  #
+  #     http = Net::HTTP.new('example.com', nil, 'my.proxy.example', 8000, 'pname', 'ppass', 'proxy.example')
+  #     http.proxy_address # => nil
+  #
+  # - Reject certain addresses and port combinations:
+  #
+  #     http = Net::HTTP.new('example.com', nil, 'proxy.example', 8000, 'pname', 'ppass', 'proxy.example:1234')
+  #     http.proxy_address # => "proxy.example"
+  #
+  #     http = Net::HTTP.new('example.com', nil, 'proxy.example', 8000, 'pname', 'ppass', 'proxy.example:8000')
+  #     http.proxy_address # => nil
+  #
+  # - Reject a list of the types above delimited using a comma:
+  #
+  #     http = Net::HTTP.new('example.com', nil, 'proxy.example', 8000, 'pname', 'ppass', 'my.proxy,proxy.example:8000')
+  #     http.proxy_address # => nil
+  #
+  #     http = Net::HTTP.new('example.com', nil, 'my.proxy', 8000, 'pname', 'ppass', 'my.proxy,proxy.example:8000')
+  #     http.proxy_address # => nil
+  #
+  # == Compression and Decompression
+  #
+  # \Net::HTTP does not compress the body of a request before sending.
+  #
+  # By default, \Net::HTTP adds header <tt>'Accept-Encoding'</tt>
+  # to a new {request object}[rdoc-ref:Net::HTTPRequest]:
+  #
+  #   Net::HTTP::Get.new(uri)['Accept-Encoding']
+  #   # => "gzip;q=1.0,deflate;q=0.6,identity;q=0.3"
+  #
+  # This requests the server to zip-encode the response body if there is one;
+  # the server is not required to do so.
+  #
+  # \Net::HTTP does not automatically decompress a response body
+  # if the response has header <tt>'Content-Range'</tt>.
+  #
+  # Otherwise decompression (or not) depends on the value of header
+  # {Content-Encoding}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#content-encoding-response-header]:
+  #
+  # - <tt>'deflate'</tt>, <tt>'gzip'</tt>, or <tt>'x-gzip'</tt>:
+  #   decompresses the body and deletes the header.
+  # - <tt>'none'</tt> or <tt>'identity'</tt>:
+  #   does not decompress the body, but deletes the header.
+  # - Any other value:
+  #   leaves the body and header unchanged.
+  #
+  # == What's Here
+  #
+  # This is a categorized summary of methods and attributes.
+  #
+  # === \Net::HTTP Objects
+  #
+  # - {::new}[rdoc-ref:Net::HTTP.new]:
+  #   Creates a new instance.
+  # - {#inspect}[rdoc-ref:Net::HTTP#inspect]:
+  #   Returns a string representation of +self+.
+  #
+  # === Sessions
+  #
+  # - {::start}[rdoc-ref:Net::HTTP.start]:
+  #   Begins a new session in a new \Net::HTTP object.
+  # - {#started?}[rdoc-ref:Net::HTTP#started?]
+  #   (aliased as {#active?}[rdoc-ref:Net::HTTP#active?]):
+  #   Returns whether in a session.
+  # - {#finish}[rdoc-ref:Net::HTTP#finish]:
+  #   Ends an active session.
+  # - {#start}[rdoc-ref:Net::HTTP#start]:
+  #   Begins a new session in an existing \Net::HTTP object (+self+).
+  #
+  # === Connections
+  #
+  # - {:continue_timeout}[rdoc-ref:Net::HTTP#continue_timeout]:
+  #   Returns the continue timeout.
+  # - {#continue_timeout=}[rdoc-ref:Net::HTTP#continue_timeout=]:
+  #   Sets the continue timeout seconds.
+  # - {:keep_alive_timeout}[rdoc-ref:Net::HTTP#keep_alive_timeout]:
+  #   Returns the keep-alive timeout.
+  # - {:keep_alive_timeout=}[rdoc-ref:Net::HTTP#keep_alive_timeout=]:
+  #   Sets the keep-alive timeout.
+  # - {:max_retries}[rdoc-ref:Net::HTTP#max_retries]:
+  #   Returns the maximum retries.
+  # - {#max_retries=}[rdoc-ref:Net::HTTP#max_retries=]:
+  #   Sets the maximum retries.
+  # - {:open_timeout}[rdoc-ref:Net::HTTP#open_timeout]:
+  #   Returns the open timeout.
+  # - {:open_timeout=}[rdoc-ref:Net::HTTP#open_timeout=]:
+  #   Sets the open timeout.
+  # - {:read_timeout}[rdoc-ref:Net::HTTP#read_timeout]:
+  #   Returns the open timeout.
+  # - {:read_timeout=}[rdoc-ref:Net::HTTP#read_timeout=]:
+  #   Sets the read timeout.
+  # - {:ssl_timeout}[rdoc-ref:Net::HTTP#ssl_timeout]:
+  #   Returns the ssl timeout.
+  # - {:ssl_timeout=}[rdoc-ref:Net::HTTP#ssl_timeout=]:
+  #   Sets the ssl timeout.
+  # - {:write_timeout}[rdoc-ref:Net::HTTP#write_timeout]:
+  #   Returns the write timeout.
+  # - {write_timeout=}[rdoc-ref:Net::HTTP#write_timeout=]:
+  #   Sets the write timeout.
+  #
+  # === Requests
+  #
+  # - {::get}[rdoc-ref:Net::HTTP.get]:
+  #   Sends a GET request and returns the string response body.
+  # - {::get_print}[rdoc-ref:Net::HTTP.get_print]:
+  #   Sends a GET request and write the string response body to $stdout.
+  # - {::get_response}[rdoc-ref:Net::HTTP.get_response]:
+  #   Sends a GET request and returns a response object.
+  # - {::post_form}[rdoc-ref:Net::HTTP.post_form]:
+  #   Sends a POST request with form data and returns a response object.
+  # - {::post}[rdoc-ref:Net::HTTP.post]:
+  #   Sends a POST request with data and returns a response object.
+  # - {#copy}[rdoc-ref:Net::HTTP#copy]:
+  #   Sends a COPY request and returns a response object.
+  # - {#delete}[rdoc-ref:Net::HTTP#delete]:
+  #   Sends a DELETE request and returns a response object.
+  # - {#get}[rdoc-ref:Net::HTTP#get]:
+  #   Sends a GET request and returns a response object.
+  # - {#head}[rdoc-ref:Net::HTTP#head]:
+  #   Sends a HEAD request and returns a response object.
+  # - {#lock}[rdoc-ref:Net::HTTP#lock]:
+  #   Sends a LOCK request and returns a response object.
+  # - {#mkcol}[rdoc-ref:Net::HTTP#mkcol]:
+  #   Sends a MKCOL request and returns a response object.
+  # - {#move}[rdoc-ref:Net::HTTP#move]:
+  #   Sends a MOVE request and returns a response object.
+  # - {#options}[rdoc-ref:Net::HTTP#options]:
+  #   Sends a OPTIONS request and returns a response object.
+  # - {#patch}[rdoc-ref:Net::HTTP#patch]:
+  #   Sends a PATCH request and returns a response object.
+  # - {#post}[rdoc-ref:Net::HTTP#post]:
+  #   Sends a POST request and returns a response object.
+  # - {#propfind}[rdoc-ref:Net::HTTP#propfind]:
+  #   Sends a PROPFIND request and returns a response object.
+  # - {#proppatch}[rdoc-ref:Net::HTTP#proppatch]:
+  #   Sends a PROPPATCH request and returns a response object.
+  # - {#put}[rdoc-ref:Net::HTTP#put]:
+  #   Sends a PUT request and returns a response object.
+  # - {#request}[rdoc-ref:Net::HTTP#request]:
+  #   Sends a request and returns a response object.
+  # - {#request_get}[rdoc-ref:Net::HTTP#request_get]
+  #   (aliased as {#get2}[rdoc-ref:Net::HTTP#get2]):
+  #   Sends a GET request and forms a response object;
+  #   if a block given, calls the block with the object,
+  #   otherwise returns the object.
+  # - {#request_head}[rdoc-ref:Net::HTTP#request_head]
+  #   (aliased as {#head2}[rdoc-ref:Net::HTTP#head2]):
+  #   Sends a HEAD request and forms a response object;
+  #   if a block given, calls the block with the object,
+  #   otherwise returns the object.
+  # - {#request_post}[rdoc-ref:Net::HTTP#request_post]
+  #   (aliased as {#post2}[rdoc-ref:Net::HTTP#post2]):
+  #   Sends a POST request and forms a response object;
+  #   if a block given, calls the block with the object,
+  #   otherwise returns the object.
+  # - {#send_request}[rdoc-ref:Net::HTTP#send_request]:
+  #   Sends a request and returns a response object.
+  # - {#trace}[rdoc-ref:Net::HTTP#trace]:
+  #   Sends a TRACE request and returns a response object.
+  # - {#unlock}[rdoc-ref:Net::HTTP#unlock]:
+  #   Sends an UNLOCK request and returns a response object.
+  #
+  # === Responses
+  #
+  # - {:close_on_empty_response}[rdoc-ref:Net::HTTP#close_on_empty_response]:
+  #   Returns whether to close connection on empty response.
+  # - {:close_on_empty_response=}[rdoc-ref:Net::HTTP#close_on_empty_response=]:
+  #   Sets whether to close connection on empty response.
+  # - {:ignore_eof}[rdoc-ref:Net::HTTP#ignore_eof]:
+  #   Returns whether to ignore end-of-file when reading a response body
+  #   with <tt>Content-Length</tt> headers.
+  # - {:ignore_eof=}[rdoc-ref:Net::HTTP#ignore_eof=]:
+  #   Sets whether to ignore end-of-file when reading a response body
+  #   with <tt>Content-Length</tt> headers.
+  # - {:response_body_encoding}[rdoc-ref:Net::HTTP#response_body_encoding]:
+  #   Returns the encoding to use for the response body.
+  # - {#response_body_encoding=}[rdoc-ref:Net::HTTP#response_body_encoding=]:
+  #   Sets the response body encoding.
   #
   # === Proxies
   #
-  # Net::HTTP will automatically create a proxy from the +http_proxy+
-  # environment variable if it is present.  To disable use of +http_proxy+,
-  # pass +nil+ for the proxy address.
-  #
-  # You may also create a custom proxy:
-  #
-  #   proxy_addr = 'your.proxy.host'
-  #   proxy_port = 8080
-  #
-  #   Net::HTTP.new('example.com', nil, proxy_addr, proxy_port).start { |http|
-  #     # always proxy via your.proxy.addr:8080
-  #   }
-  #
-  # See Net::HTTP.new for further details and examples such as proxies that
-  # require a username and password.
-  #
-  # === Compression
-  #
-  # Net::HTTP automatically adds Accept-Encoding for compression of response
-  # bodies and automatically decompresses gzip and deflate responses unless a
-  # Range header was sent.
-  #
-  # Compression can be disabled through the Accept-Encoding: identity header.
-  #
-  # == HTTP Request Classes
-  #
-  # Here is the HTTP request class hierarchy.
-  #
-  # * Net::HTTPRequest
-  #   * Net::HTTP::Get
-  #   * Net::HTTP::Head
-  #   * Net::HTTP::Post
-  #   * Net::HTTP::Patch
-  #   * Net::HTTP::Put
-  #   * Net::HTTP::Proppatch
-  #   * Net::HTTP::Lock
-  #   * Net::HTTP::Unlock
-  #   * Net::HTTP::Options
-  #   * Net::HTTP::Propfind
-  #   * Net::HTTP::Delete
-  #   * Net::HTTP::Move
-  #   * Net::HTTP::Copy
-  #   * Net::HTTP::Mkcol
-  #   * Net::HTTP::Trace
-  #
-  # == HTTP Response Classes
-  #
-  # Here is HTTP response class hierarchy.  All classes are defined in Net
-  # module and are subclasses of Net::HTTPResponse.
-  #
-  # HTTPUnknownResponse:: For unhandled HTTP extensions
-  # HTTPInformation::                    1xx
-  #   HTTPContinue::                        100
-  #   HTTPSwitchProtocol::                  101
-  #   HTTPProcessing::                      102
-  #   HTTPEarlyHints::                      103
-  # HTTPSuccess::                        2xx
-  #   HTTPOK::                              200
-  #   HTTPCreated::                         201
-  #   HTTPAccepted::                        202
-  #   HTTPNonAuthoritativeInformation::     203
-  #   HTTPNoContent::                       204
-  #   HTTPResetContent::                    205
-  #   HTTPPartialContent::                  206
-  #   HTTPMultiStatus::                     207
-  #   HTTPAlreadyReported::                 208
-  #   HTTPIMUsed::                          226
-  # HTTPRedirection::                    3xx
-  #   HTTPMultipleChoices::                 300
-  #   HTTPMovedPermanently::                301
-  #   HTTPFound::                           302
-  #   HTTPSeeOther::                        303
-  #   HTTPNotModified::                     304
-  #   HTTPUseProxy::                        305
-  #   HTTPTemporaryRedirect::               307
-  #   HTTPPermanentRedirect::               308
-  # HTTPClientError::                    4xx
-  #   HTTPBadRequest::                      400
-  #   HTTPUnauthorized::                    401
-  #   HTTPPaymentRequired::                 402
-  #   HTTPForbidden::                       403
-  #   HTTPNotFound::                        404
-  #   HTTPMethodNotAllowed::                405
-  #   HTTPNotAcceptable::                   406
-  #   HTTPProxyAuthenticationRequired::     407
-  #   HTTPRequestTimeOut::                  408
-  #   HTTPConflict::                        409
-  #   HTTPGone::                            410
-  #   HTTPLengthRequired::                  411
-  #   HTTPPreconditionFailed::              412
-  #   HTTPRequestEntityTooLarge::           413
-  #   HTTPRequestURITooLong::               414
-  #   HTTPUnsupportedMediaType::            415
-  #   HTTPRequestedRangeNotSatisfiable::    416
-  #   HTTPExpectationFailed::               417
-  #   HTTPMisdirectedRequest::              421
-  #   HTTPUnprocessableEntity::             422
-  #   HTTPLocked::                          423
-  #   HTTPFailedDependency::                424
-  #   HTTPUpgradeRequired::                 426
-  #   HTTPPreconditionRequired::            428
-  #   HTTPTooManyRequests::                 429
-  #   HTTPRequestHeaderFieldsTooLarge::     431
-  #   HTTPUnavailableForLegalReasons::      451
-  # HTTPServerError::                    5xx
-  #   HTTPInternalServerError::             500
-  #   HTTPNotImplemented::                  501
-  #   HTTPBadGateway::                      502
-  #   HTTPServiceUnavailable::              503
-  #   HTTPGatewayTimeOut::                  504
-  #   HTTPVersionNotSupported::             505
-  #   HTTPVariantAlsoNegotiates::           506
-  #   HTTPInsufficientStorage::             507
-  #   HTTPLoopDetected::                    508
-  #   HTTPNotExtended::                     510
-  #   HTTPNetworkAuthenticationRequired::   511
-  #
-  # There is also the Net::HTTPBadResponse exception which is raised when
-  # there is a protocol error.
+  # - {:proxy_address}[rdoc-ref:Net::HTTP#proxy_address]:
+  #   Returns the proxy address.
+  # - {:proxy_address=}[rdoc-ref:Net::HTTP#proxy_address=]:
+  #   Sets the proxy address.
+  # - {::proxy_class?}[rdoc-ref:Net::HTTP.proxy_class?]:
+  #   Returns whether +self+ is a proxy class.
+  # - {#proxy?}[rdoc-ref:Net::HTTP#proxy?]:
+  #   Returns whether +self+ has a proxy.
+  # - {#proxy_address}[rdoc-ref:Net::HTTP#proxy_address]
+  #   (aliased as {#proxyaddr}[rdoc-ref:Net::HTTP#proxyaddr]):
+  #   Returns the proxy address.
+  # - {#proxy_from_env?}[rdoc-ref:Net::HTTP#proxy_from_env?]:
+  #   Returns whether the proxy is taken from an environment variable.
+  # - {:proxy_from_env=}[rdoc-ref:Net::HTTP#proxy_from_env=]:
+  #   Sets whether the proxy is to be taken from an environment variable.
+  # - {:proxy_pass}[rdoc-ref:Net::HTTP#proxy_pass]:
+  #   Returns the proxy password.
+  # - {:proxy_pass=}[rdoc-ref:Net::HTTP#proxy_pass=]:
+  #   Sets the proxy password.
+  # - {:proxy_port}[rdoc-ref:Net::HTTP#proxy_port]:
+  #   Returns the proxy port.
+  # - {:proxy_port=}[rdoc-ref:Net::HTTP#proxy_port=]:
+  #   Sets the proxy port.
+  # - {#proxy_user}[rdoc-ref:Net::HTTP#proxy_user]:
+  #   Returns the proxy user name.
+  # - {:proxy_user=}[rdoc-ref:Net::HTTP#proxy_user=]:
+  #   Sets the proxy user.
+  #
+  # === Security
+  #
+  # - {:ca_file}[rdoc-ref:Net::HTTP#ca_file]:
+  #   Returns the path to a CA certification file.
+  # - {:ca_file=}[rdoc-ref:Net::HTTP#ca_file=]:
+  #   Sets the path to a CA certification file.
+  # - {:ca_path}[rdoc-ref:Net::HTTP#ca_path]:
+  #   Returns the path of to CA directory containing certification files.
+  # - {:ca_path=}[rdoc-ref:Net::HTTP#ca_path=]:
+  #   Sets the path of to CA directory containing certification files.
+  # - {:cert}[rdoc-ref:Net::HTTP#cert]:
+  #   Returns the OpenSSL::X509::Certificate object to be used for client certification.
+  # - {:cert=}[rdoc-ref:Net::HTTP#cert=]:
+  #   Sets the OpenSSL::X509::Certificate object to be used for client certification.
+  # - {:cert_store}[rdoc-ref:Net::HTTP#cert_store]:
+  #   Returns the X509::Store to be used for verifying peer certificate.
+  # - {:cert_store=}[rdoc-ref:Net::HTTP#cert_store=]:
+  #   Sets the X509::Store to be used for verifying peer certificate.
+  # - {:ciphers}[rdoc-ref:Net::HTTP#ciphers]:
+  #   Returns the available SSL ciphers.
+  # - {:ciphers=}[rdoc-ref:Net::HTTP#ciphers=]:
+  #   Sets the available SSL ciphers.
+  # - {:extra_chain_cert}[rdoc-ref:Net::HTTP#extra_chain_cert]:
+  #   Returns the extra X509 certificates to be added to the certificate chain.
+  # - {:extra_chain_cert=}[rdoc-ref:Net::HTTP#extra_chain_cert=]:
+  #   Sets the extra X509 certificates to be added to the certificate chain.
+  # - {:key}[rdoc-ref:Net::HTTP#key]:
+  #   Returns the OpenSSL::PKey::RSA or OpenSSL::PKey::DSA object.
+  # - {:key=}[rdoc-ref:Net::HTTP#key=]:
+  #   Sets the OpenSSL::PKey::RSA or OpenSSL::PKey::DSA object.
+  # - {:max_version}[rdoc-ref:Net::HTTP#max_version]:
+  #   Returns the maximum SSL version.
+  # - {:max_version=}[rdoc-ref:Net::HTTP#max_version=]:
+  #   Sets the maximum SSL version.
+  # - {:min_version}[rdoc-ref:Net::HTTP#min_version]:
+  #   Returns the minimum SSL version.
+  # - {:min_version=}[rdoc-ref:Net::HTTP#min_version=]:
+  #   Sets the minimum SSL version.
+  # - {#peer_cert}[rdoc-ref:Net::HTTP#peer_cert]:
+  #   Returns the X509 certificate chain for the session's socket peer.
+  # - {:ssl_version}[rdoc-ref:Net::HTTP#ssl_version]:
+  #   Returns the SSL version.
+  # - {:ssl_version=}[rdoc-ref:Net::HTTP#ssl_version=]:
+  #   Sets the SSL version.
+  # - {#use_ssl=}[rdoc-ref:Net::HTTP#use_ssl=]:
+  #   Sets whether a new session is to use Transport Layer Security.
+  # - {#use_ssl?}[rdoc-ref:Net::HTTP#use_ssl?]:
+  #   Returns whether +self+ uses SSL.
+  # - {:verify_callback}[rdoc-ref:Net::HTTP#verify_callback]:
+  #   Returns the callback for the server certification verification.
+  # - {:verify_callback=}[rdoc-ref:Net::HTTP#verify_callback=]:
+  #   Sets the callback for the server certification verification.
+  # - {:verify_depth}[rdoc-ref:Net::HTTP#verify_depth]:
+  #   Returns the maximum depth for the certificate chain verification.
+  # - {:verify_depth=}[rdoc-ref:Net::HTTP#verify_depth=]:
+  #   Sets the maximum depth for the certificate chain verification.
+  # - {:verify_hostname}[rdoc-ref:Net::HTTP#verify_hostname]:
+  #   Returns the flags for server the certification verification at the beginning of the SSL/TLS session.
+  # - {:verify_hostname=}[rdoc-ref:Net::HTTP#verify_hostname=]:
+  #   Sets he flags for server the certification verification at the beginning of the SSL/TLS session.
+  # - {:verify_mode}[rdoc-ref:Net::HTTP#verify_mode]:
+  #   Returns the flags for server the certification verification at the beginning of the SSL/TLS session.
+  # - {:verify_mode=}[rdoc-ref:Net::HTTP#verify_mode=]:
+  #   Sets the flags for server the certification verification at the beginning of the SSL/TLS session.
+  #
+  # === Addresses and Ports
+  #
+  # - {:address}[rdoc-ref:Net::HTTP#address]:
+  #   Returns the string host name or host IP.
+  # - {::default_port}[rdoc-ref:Net::HTTP.default_port]:
+  #   Returns integer 80, the default port to use for HTTP requests.
+  # - {::http_default_port}[rdoc-ref:Net::HTTP.http_default_port]:
+  #   Returns integer 80, the default port to use for HTTP requests.
+  # - {::https_default_port}[rdoc-ref:Net::HTTP.https_default_port]:
+  #   Returns integer 443, the default port to use for HTTPS requests.
+  # - {#ipaddr}[rdoc-ref:Net::HTTP#ipaddr]:
+  #   Returns the IP address for the connection.
+  # - {#ipaddr=}[rdoc-ref:Net::HTTP#ipaddr=]:
+  #   Sets the IP address for the connection.
+  # - {:local_host}[rdoc-ref:Net::HTTP#local_host]:
+  #   Returns the string local host used to establish the connection.
+  # - {:local_host=}[rdoc-ref:Net::HTTP#local_host=]:
+  #   Sets the string local host used to establish the connection.
+  # - {:local_port}[rdoc-ref:Net::HTTP#local_port]:
+  #   Returns the integer local port used to establish the connection.
+  # - {:local_port=}[rdoc-ref:Net::HTTP#local_port=]:
+  #   Sets the integer local port used to establish the connection.
+  # - {:port}[rdoc-ref:Net::HTTP#port]:
+  #   Returns the integer port number.
+  #
+  # === \HTTP Version
+  #
+  # - {::version_1_2?}[rdoc-ref:Net::HTTP.version_1_2?]
+  #   (aliased as {::is_version_1_2?}[rdoc-ref:Net::HTTP.is_version_1_2?]
+  #   and {::version_1_2}[rdoc-ref:Net::HTTP.version_1_2]):
+  #   Returns true; retained for compatibility.
+  #
+  # === Debugging
+  #
+  # - {#set_debug_output}[rdoc-ref:Net::HTTP#set_debug_output]:
+  #   Sets the output stream for debugging.
   #
   class HTTP < Protocol
 
     # :stopdoc:
-    VERSION = "0.2.0"
-    Revision = %q$Revision$.split[1]
+    VERSION = "0.4.1"
     HTTPVersion = '1.1'
     begin
       require 'zlib'
@@ -408,18 +732,17 @@ module Net   #:nodoc:
     end
     # :startdoc:
 
-    # Turns on net/http 1.2 (Ruby 1.8) features.
-    # Defaults to ON in Ruby 1.8 or later.
+    # Returns +true+; retained for compatibility.
     def HTTP.version_1_2
       true
     end
 
-    # Returns true if net/http is in version 1.2 mode.
-    # Defaults to true.
+    # Returns +true+; retained for compatibility.
     def HTTP.version_1_2?
       true
     end
 
+    # Returns +false+; retained for compatibility.
     def HTTP.version_1_1?  #:nodoc:
       false
     end
@@ -429,25 +752,12 @@ module Net   #:nodoc:
       alias is_version_1_2? version_1_2?   #:nodoc:
     end
 
+    # :call-seq:
+    #   Net::HTTP.get_print(hostname, path, port = 80) -> nil
+    #   Net::HTTP:get_print(uri, headers = {}, port = uri.port) -> nil
     #
-    # short cut methods
-    #
-
-    #
-    # Gets the body text from the target and outputs it to $stdout.  The
-    # target can either be specified as
-    # (+uri+, +headers+), or as (+host+, +path+, +port+ = 80); so:
-    #
-    #    Net::HTTP.get_print URI('http://www.example.com/index.html')
-    #
-    # or:
-    #
-    #    Net::HTTP.get_print 'www.example.com', '/index.html'
-    #
-    # you can also specify request headers:
-    #
-    #    Net::HTTP.get_print URI('http://www.example.com/index.html'), { 'Accept' => 'text/html' }
-    #
+    # Like Net::HTTP.get, but writes the returned body to $stdout;
+    # returns +nil+.
     def HTTP.get_print(uri_or_host, path_or_headers = nil, port = nil)
       get_response(uri_or_host, path_or_headers, port) {|res|
         res.read_body do |chunk|
@@ -457,40 +767,48 @@ module Net   #:nodoc:
       nil
     end
 
-    # Sends a GET request to the target and returns the HTTP response
-    # as a string.  The target can either be specified as
-    # (+uri+, +headers+), or as (+host+, +path+, +port+ = 80); so:
-    #
-    #    print Net::HTTP.get(URI('http://www.example.com/index.html'))
+    # :call-seq:
+    #   Net::HTTP.get(hostname, path, port = 80) -> body
+    #   Net::HTTP:get(uri, headers = {}, port = uri.port) -> body
     #
-    # or:
+    # Sends a GET request and returns the \HTTP response body as a string.
     #
-    #    print Net::HTTP.get('www.example.com', '/index.html')
+    # With string arguments +hostname+ and +path+:
     #
-    # you can also specify request headers:
+    #   hostname = 'jsonplaceholder.typicode.com'
+    #   path = '/todos/1'
+    #   puts Net::HTTP.get(hostname, path)
     #
-    #    Net::HTTP.get(URI('http://www.example.com/index.html'), { 'Accept' => 'text/html' })
+    # Output:
     #
-    def HTTP.get(uri_or_host, path_or_headers = nil, port = nil)
-      get_response(uri_or_host, path_or_headers, port).body
-    end
-
-    # Sends a GET request to the target and returns the HTTP response
-    # as a Net::HTTPResponse object.  The target can either be specified as
-    # (+uri+, +headers+), or as (+host+, +path+, +port+ = 80); so:
+    #   {
+    #     "userId": 1,
+    #     "id": 1,
+    #     "title": "delectus aut autem",
+    #     "completed": false
+    #   }
     #
-    #    res = Net::HTTP.get_response(URI('http://www.example.com/index.html'))
-    #    print res.body
+    # With URI object +uri+ and optional hash argument +headers+:
     #
-    # or:
+    #   uri = URI('https://jsonplaceholder.typicode.com/todos/1')
+    #   headers = {'Content-type' => 'application/json; charset=UTF-8'}
+    #   Net::HTTP.get(uri, headers)
     #
-    #    res = Net::HTTP.get_response('www.example.com', '/index.html')
-    #    print res.body
+    # Related:
     #
-    # you can also specify request headers:
+    # - Net::HTTP::Get: request class for \HTTP method +GET+.
+    # - Net::HTTP#get: convenience method for \HTTP method +GET+.
     #
-    #    Net::HTTP.get_response(URI('http://www.example.com/index.html'), { 'Accept' => 'text/html' })
+    def HTTP.get(uri_or_host, path_or_headers = nil, port = nil)
+      get_response(uri_or_host, path_or_headers, port).body
+    end
+
+    # :call-seq:
+    #   Net::HTTP.get_response(hostname, path, port = 80) -> http_response
+    #   Net::HTTP:get_response(uri, headers = {}, port = uri.port) -> http_response
     #
+    # Like Net::HTTP.get, but returns a Net::HTTPResponse object
+    # instead of the body string.
     def HTTP.get_response(uri_or_host, path_or_headers = nil, port = nil, &block)
       if path_or_headers && !path_or_headers.is_a?(Hash)
         host = uri_or_host
@@ -508,16 +826,31 @@ module Net   #:nodoc:
       end
     end
 
-    # Posts data to the specified URI object.
+    # Posts data to a host; returns a Net::HTTPResponse object.
     #
-    # Example:
+    # Argument +url+ must be a URL;
+    # argument +data+ must be a string:
+    #
+    #   _uri = uri.dup
+    #   _uri.path = '/posts'
+    #   data = '{"title": "foo", "body": "bar", "userId": 1}'
+    #   headers = {'content-type': 'application/json'}
+    #   res = Net::HTTP.post(_uri, data, headers) # => #<Net::HTTPCreated 201 Created readbody=true>
+    #   puts res.body
+    #
+    # Output:
+    #
+    #   {
+    #     "title": "foo",
+    #     "body": "bar",
+    #     "userId": 1,
+    #     "id": 101
+    #   }
     #
-    #   require 'net/http'
-    #   require 'uri'
+    # Related:
     #
-    #   Net::HTTP.post URI('http://www.example.com/api/search'),
-    #                  { "q" => "ruby", "max" => "50" }.to_json,
-    #                  "Content-Type" => "application/json"
+    # - Net::HTTP::Post: request class for \HTTP method +POST+.
+    # - Net::HTTP#post: convenience method for \HTTP method +POST+.
     #
     def HTTP.post(url, data, header = nil)
       start(url.hostname, url.port,
@@ -526,22 +859,25 @@ module Net   #:nodoc:
       }
     end
 
-    # Posts HTML form data to the specified URI object.
-    # The form data must be provided as a Hash mapping from String to String.
-    # Example:
-    #
-    #   { "cmd" => "search", "q" => "ruby", "max" => "50" }
+    # Posts data to a host; returns a Net::HTTPResponse object.
     #
-    # This method also does Basic Authentication if and only if +url+.user exists.
-    # But userinfo for authentication is deprecated (RFC3986).
-    # So this feature will be removed.
+    # Argument +url+ must be a URI;
+    # argument +data+ must be a hash:
     #
-    # Example:
+    #   _uri = uri.dup
+    #   _uri.path = '/posts'
+    #   data = {title: 'foo', body: 'bar', userId: 1}
+    #   res = Net::HTTP.post_form(_uri, data) # => #<Net::HTTPCreated 201 Created readbody=true>
+    #   puts res.body
     #
-    #   require 'net/http'
+    # Output:
     #
-    #   Net::HTTP.post_form URI('http://www.example.com/search.cgi'),
-    #                       { "q" => "ruby", "max" => "50" }
+    #   {
+    #     "title": "foo",
+    #     "body": "bar",
+    #     "userId": "1",
+    #     "id": 101
+    #   }
     #
     def HTTP.post_form(url, params)
       req = Post.new(url)
@@ -554,20 +890,29 @@ module Net   #:nodoc:
     end
 
     #
-    # HTTP session management
+    # \HTTP session management
     #
 
-    # The default port to use for HTTP requests; defaults to 80.
+    # Returns integer +80+, the default port to use for \HTTP requests:
+    #
+    #   Net::HTTP.default_port # => 80
+    #
     def HTTP.default_port
       http_default_port()
     end
 
-    # The default port to use for HTTP requests; defaults to 80.
+    # Returns integer +80+, the default port to use for \HTTP requests:
+    #
+    #   Net::HTTP.http_default_port # => 80
+    #
     def HTTP.http_default_port
       80
     end
 
-    # The default port to use for HTTPS requests; defaults to 443.
+    # Returns integer +443+, the default port to use for HTTPS requests:
+    #
+    #   Net::HTTP.https_default_port # => 443
+    #
     def HTTP.https_default_port
       443
     end
@@ -577,35 +922,91 @@ module Net   #:nodoc:
     end
 
     # :call-seq:
-    #   HTTP.start(address, port, p_addr, p_port, p_user, p_pass, &block)
-    #   HTTP.start(address, port=nil, p_addr=:ENV, p_port=nil, p_user=nil, p_pass=nil, opt, &block)
-    #
-    # Creates a new Net::HTTP object, then additionally opens the TCP
-    # connection and HTTP session.
-    #
-    # Arguments are the following:
-    # _address_ :: hostname or IP address of the server
-    # _port_    :: port of the server
-    # _p_addr_  :: address of proxy
-    # _p_port_  :: port of proxy
-    # _p_user_  :: user of proxy
-    # _p_pass_  :: pass of proxy
-    # _opt_     :: optional hash
-    #
-    # _opt_ sets following values by its accessor.
-    # The keys are ipaddr, ca_file, ca_path, cert, cert_store, ciphers, keep_alive_timeout,
-    # close_on_empty_response, key, open_timeout, read_timeout, write_timeout, ssl_timeout,
-    # ssl_version, use_ssl, verify_callback, verify_depth and verify_mode.
-    # If you set :use_ssl as true, you can use https and default value of
-    # verify_mode is set as OpenSSL::SSL::VERIFY_PEER.
-    #
-    # If the optional block is given, the newly
-    # created Net::HTTP object is passed to it and closed when the
-    # block finishes.  In this case, the return value of this method
-    # is the return value of the block.  If no block is given, the
-    # return value of this method is the newly created Net::HTTP object
-    # itself, and the caller is responsible for closing it upon completion
-    # using the finish() method.
+    #   HTTP.start(address, port = nil, p_addr = :ENV, p_port = nil, p_user = nil, p_pass = nil, opts) -> http
+    #   HTTP.start(address, port = nil, p_addr = :ENV, p_port = nil, p_user = nil, p_pass = nil, opts) {|http| ... } -> object
+    #
+    # Creates a new \Net::HTTP object, +http+, via \Net::HTTP.new:
+    #
+    # - For arguments +address+ and +port+, see Net::HTTP.new.
+    # - For proxy-defining arguments +p_addr+ through +p_pass+,
+    #   see {Proxy Server}[rdoc-ref:Net::HTTP@Proxy+Server].
+    # - For argument +opts+, see below.
+    #
+    # With no block given:
+    #
+    # - Calls <tt>http.start</tt> with no block (see #start),
+    #   which opens a TCP connection and \HTTP session.
+    # - Returns +http+.
+    # - The caller should call #finish to close the session:
+    #
+    #     http = Net::HTTP.start(hostname)
+    #     http.started? # => true
+    #     http.finish
+    #     http.started? # => false
+    #
+    # With a block given:
+    #
+    # - Calls <tt>http.start</tt> with the block (see #start), which:
+    #
+    #   - Opens a TCP connection and \HTTP session.
+    #   - Calls the block,
+    #     which may make any number of requests to the host.
+    #   - Closes the \HTTP session and TCP connection on block exit.
+    #   - Returns the block's value +object+.
+    #
+    # - Returns +object+.
+    #
+    # Example:
+    #
+    #   hostname = 'jsonplaceholder.typicode.com'
+    #   Net::HTTP.start(hostname) do |http|
+    #     puts http.get('/todos/1').body
+    #     puts http.get('/todos/2').body
+    #   end
+    #
+    # Output:
+    #
+    #   {
+    #     "userId": 1,
+    #     "id": 1,
+    #     "title": "delectus aut autem",
+    #     "completed": false
+    #   }
+    #   {
+    #     "userId": 1,
+    #     "id": 2,
+    #     "title": "quis ut nam facilis et officia qui",
+    #     "completed": false
+    #   }
+    #
+    # If the last argument given is a hash, it is the +opts+ hash,
+    # where each key is a method or accessor to be called,
+    # and its value is the value to be set.
+    #
+    # The keys may include:
+    #
+    # - #ca_file
+    # - #ca_path
+    # - #cert
+    # - #cert_store
+    # - #ciphers
+    # - #close_on_empty_response
+    # - +ipaddr+ (calls #ipaddr=)
+    # - #keep_alive_timeout
+    # - #key
+    # - #open_timeout
+    # - #read_timeout
+    # - #ssl_timeout
+    # - #ssl_version
+    # - +use_ssl+ (calls #use_ssl=)
+    # - #verify_callback
+    # - #verify_depth
+    # - #verify_mode
+    # - #write_timeout
+    #
+    # Note: If +port+ is +nil+ and <tt>opts[:use_ssl]</tt> is a truthy value,
+    # the value passed to +new+ is Net::HTTP.https_default_port, not +port+.
+    #
     def HTTP.start(address, *arg, &block) # :yield: +http+
       arg.pop if opt = Hash.try_convert(arg[-1])
       port, p_addr, p_port, p_user, p_pass = *arg
@@ -632,25 +1033,34 @@ module Net   #:nodoc:
       alias newobj new # :nodoc:
     end
 
-    # Creates a new Net::HTTP object without opening a TCP connection or
-    # HTTP session.
+    # Returns a new \Net::HTTP object +http+
+    # (but does not open a TCP connection or \HTTP session).
+    #
+    # With only string argument +address+ given
+    # (and <tt>ENV['http_proxy']</tt> undefined or +nil+),
+    # the returned +http+:
+    #
+    # - Has the given address.
+    # - Has the default port number, Net::HTTP.default_port (80).
+    # - Has no proxy.
+    #
+    # Example:
+    #
+    #   http = Net::HTTP.new(hostname)
+    #   # => #<Net::HTTP jsonplaceholder.typicode.com:80 open=false>
+    #   http.address # => "jsonplaceholder.typicode.com"
+    #   http.port    # => 80
+    #   http.proxy?  # => false
     #
-    # The +address+ should be a DNS hostname or IP address, the +port+ is the
-    # port the server operates on.  If no +port+ is given the default port for
-    # HTTP or HTTPS is used.
+    # With integer argument +port+ also given,
+    # the returned +http+ has the given port:
     #
-    # If none of the +p_+ arguments are given, the proxy host and port are
-    # taken from the +http_proxy+ environment variable (or its uppercase
-    # equivalent) if present.  If the proxy requires authentication you must
-    # supply it by hand.  See URI::Generic#find_proxy for details of proxy
-    # detection from the environment.  To disable proxy detection set +p_addr+
-    # to nil.
+    #   http = Net::HTTP.new(hostname, 8000)
+    #   # => #<Net::HTTP jsonplaceholder.typicode.com:8000 open=false>
+    #   http.port # => 8000
     #
-    # If you are connecting to a custom proxy, +p_addr+ specifies the DNS name
-    # or IP address of the proxy host, +p_port+ the port to use to access the
-    # proxy, +p_user+ and +p_pass+ the username and password if authorization
-    # is required to use the proxy, and p_no_proxy hosts which do not
-    # use the proxy.
+    # For proxy-defining arguments +p_addr+ through +p_no_proxy+,
+    # see {Proxy Server}[rdoc-ref:Net::HTTP@Proxy+Server].
     #
     def HTTP.new(address, port = nil, p_addr = :ENV, p_port = nil, p_user = nil, p_pass = nil, p_no_proxy = nil)
       http = super address, port
@@ -664,7 +1074,7 @@ module Net   #:nodoc:
       elsif p_addr == :ENV then
         http.proxy_from_env = true
       else
-        if p_addr && p_no_proxy && !URI::Generic.use_proxy?(p_addr, p_addr, p_port, p_no_proxy)
+        if p_addr && p_no_proxy && !URI::Generic.use_proxy?(address, address, port, p_no_proxy)
           p_addr = nil
           p_port = nil
         end
@@ -677,10 +1087,10 @@ module Net   #:nodoc:
       http
     end
 
-    # Creates a new Net::HTTP object for the specified server address,
-    # without opening the TCP connection or initializing the HTTP session.
+    # Creates a new \Net::HTTP object for the specified server address,
+    # without opening the TCP connection or initializing the \HTTP session.
     # The +address+ should be a DNS hostname or IP address.
-    def initialize(address, port = nil)
+    def initialize(address, port = nil) # :nodoc:
       @address = address
       @port    = (port || HTTP.default_port)
       @ipaddr = nil
@@ -699,6 +1109,7 @@ module Net   #:nodoc:
       @max_retries = 1
       @debug_output = nil
       @response_body_encoding = false
+      @ignore_eof = true
 
       @proxy_from_env = false
       @proxy_uri      = nil
@@ -716,6 +1127,11 @@ module Net   #:nodoc:
       end
     end
 
+    # Returns a string representation of +self+:
+    #
+    #   Net::HTTP.new(hostname).inspect
+    #   # => "#<Net::HTTP jsonplaceholder.typicode.com:80 open=false>"
+    #
     def inspect
       "#<#{self.class} #{@address}:#{@port} open=#{started?}>"
     end
@@ -723,83 +1139,184 @@ module Net   #:nodoc:
     # *WARNING* This method opens a serious security hole.
     # Never use this method in production code.
     #
-    # Sets an output stream for debugging.
+    # Sets the output stream for debugging:
     #
     #   http = Net::HTTP.new(hostname)
-    #   http.set_debug_output $stderr
-    #   http.start { .... }
+    #   File.open('t.tmp', 'w') do |file|
+    #     http.set_debug_output(file)
+    #     http.start
+    #     http.get('/nosuch/1')
+    #     http.finish
+    #   end
+    #   puts File.read('t.tmp')
+    #
+    # Output:
+    #
+    #   opening connection to jsonplaceholder.typicode.com:80...
+    #   opened
+    #   <- "GET /nosuch/1 HTTP/1.1\r\nAccept-Encoding: gzip;q=1.0,deflate;q=0.6,identity;q=0.3\r\nAccept: */*\r\nUser-Agent: Ruby\r\nHost: jsonplaceholder.typicode.com\r\n\r\n"
+    #   -> "HTTP/1.1 404 Not Found\r\n"
+    #   -> "Date: Mon, 12 Dec 2022 21:14:11 GMT\r\n"
+    #   -> "Content-Type: application/json; charset=utf-8\r\n"
+    #   -> "Content-Length: 2\r\n"
+    #   -> "Connection: keep-alive\r\n"
+    #   -> "X-Powered-By: Express\r\n"
+    #   -> "X-Ratelimit-Limit: 1000\r\n"
+    #   -> "X-Ratelimit-Remaining: 999\r\n"
+    #   -> "X-Ratelimit-Reset: 1670879660\r\n"
+    #   -> "Vary: Origin, Accept-Encoding\r\n"
+    #   -> "Access-Control-Allow-Credentials: true\r\n"
+    #   -> "Cache-Control: max-age=43200\r\n"
+    #   -> "Pragma: no-cache\r\n"
+    #   -> "Expires: -1\r\n"
+    #   -> "X-Content-Type-Options: nosniff\r\n"
+    #   -> "Etag: W/\"2-vyGp6PvFo4RvsFtPoIWeCReyIC8\"\r\n"
+    #   -> "Via: 1.1 vegur\r\n"
+    #   -> "CF-Cache-Status: MISS\r\n"
+    #   -> "Server-Timing: cf-q-config;dur=1.3000000762986e-05\r\n"
+    #   -> "Report-To: {\"endpoints\":[{\"url\":\"https:\\/\\/a.nel.cloudflare.com\\/report\\/v3?s=yOr40jo%2BwS1KHzhTlVpl54beJ5Wx2FcG4gGV0XVrh3X9OlR5q4drUn2dkt5DGO4GDcE%2BVXT7CNgJvGs%2BZleIyMu8CLieFiDIvOviOY3EhHg94m0ZNZgrEdpKD0S85S507l1vsEwEHkoTm%2Ff19SiO\"}],\"group\":\"cf-nel\",\"max_age\":604800}\r\n"
+    #   -> "NEL: {\"success_fraction\":0,\"report_to\":\"cf-nel\",\"max_age\":604800}\r\n"
+    #   -> "Server: cloudflare\r\n"
+    #   -> "CF-RAY: 778977dc484ce591-DFW\r\n"
+    #   -> "alt-svc: h3=\":443\"; ma=86400, h3-29=\":443\"; ma=86400\r\n"
+    #   -> "\r\n"
+    #   reading 2 bytes...
+    #   -> "{}"
+    #   read 2 bytes
+    #   Conn keep-alive
     #
     def set_debug_output(output)
       warn 'Net::HTTP#set_debug_output called after HTTP started', uplevel: 1 if started?
       @debug_output = output
     end
 
-    # The DNS host name or IP address to connect to.
+    # Returns the string host name or host IP given as argument +address+ in ::new.
     attr_reader :address
 
-    # The port number to connect to.
+    # Returns the integer port number given as argument +port+ in ::new.
     attr_reader :port
 
-    # The local host used to establish the connection.
+    # Sets or returns the string local host used to establish the connection;
+    # initially +nil+.
     attr_accessor :local_host
 
-    # The local port used to establish the connection.
+    # Sets or returns the integer local port used to establish the connection;
+    # initially +nil+.
     attr_accessor :local_port
 
-    # The encoding to use for the response body.  If Encoding, uses the
-    # specified encoding.  If other true value, tries to detect the response
-    # body encoding.
+    # Returns the encoding to use for the response body;
+    # see #response_body_encoding=.
     attr_reader :response_body_encoding
 
-    # Set the encoding to use for the response body.  If given a String, find
-    # the related Encoding.
+    # Sets the encoding to be used for the response body;
+    # returns the encoding.
+    #
+    # The given +value+ may be:
+    #
+    # - An Encoding object.
+    # - The name of an encoding.
+    # - An alias for an encoding name.
+    #
+    # See {Encoding}[rdoc-ref:Encoding].
+    #
+    # Examples:
+    #
+    #   http = Net::HTTP.new(hostname)
+    #   http.response_body_encoding = Encoding::US_ASCII # => #<Encoding:US-ASCII>
+    #   http.response_body_encoding = 'US-ASCII'         # => "US-ASCII"
+    #   http.response_body_encoding = 'ASCII'            # => "ASCII"
+    #
     def response_body_encoding=(value)
       value = Encoding.find(value) if value.is_a?(String)
       @response_body_encoding = value
     end
 
+    # Sets whether to determine the proxy from environment variable
+    # '<tt>ENV['http_proxy']</tt>';
+    # see {Proxy Using ENV['http_proxy']}[rdoc-ref:Net::HTTP@Proxy+Using+-27ENV-5B-27http_proxy-27-5D-27].
     attr_writer :proxy_from_env
+
+    # Sets the proxy address;
+    # see {Proxy Server}[rdoc-ref:Net::HTTP@Proxy+Server].
     attr_writer :proxy_address
+
+    # Sets the proxy port;
+    # see {Proxy Server}[rdoc-ref:Net::HTTP@Proxy+Server].
     attr_writer :proxy_port
+
+    # Sets the proxy user;
+    # see {Proxy Server}[rdoc-ref:Net::HTTP@Proxy+Server].
     attr_writer :proxy_user
+
+    # Sets the proxy password;
+    # see {Proxy Server}[rdoc-ref:Net::HTTP@Proxy+Server].
     attr_writer :proxy_pass
 
-    # The IP address to connect to/used to connect to
+    # Returns the IP address for the connection.
+    #
+    # If the session has not been started,
+    # returns the value set by #ipaddr=,
+    # or +nil+ if it has not been set:
+    #
+    #   http = Net::HTTP.new(hostname)
+    #   http.ipaddr # => nil
+    #   http.ipaddr = '172.67.155.76'
+    #   http.ipaddr # => "172.67.155.76"
+    #
+    # If the session has been started,
+    # returns the IP address from the socket:
+    #
+    #   http = Net::HTTP.new(hostname)
+    #   http.start
+    #   http.ipaddr # => "172.67.155.76"
+    #   http.finish
+    #
     def ipaddr
       started? ?  @socket.io.peeraddr[3] : @ipaddr
     end
 
-    # Set the IP address to connect to
+    # Sets the IP address for the connection:
+    #
+    #   http = Net::HTTP.new(hostname)
+    #   http.ipaddr # => nil
+    #   http.ipaddr = '172.67.155.76'
+    #   http.ipaddr # => "172.67.155.76"
+    #
+    # The IP address may not be set if the session has been started.
     def ipaddr=(addr)
       raise IOError, "ipaddr value changed, but session already started" if started?
       @ipaddr = addr
     end
 
-    # Number of seconds to wait for the connection to open. Any number
-    # may be used, including Floats for fractional seconds. If the HTTP
-    # object cannot open a connection in this many seconds, it raises a
-    # Net::OpenTimeout exception. The default value is 60 seconds.
+    # Sets or returns the numeric (\Integer or \Float) number of seconds
+    # to wait for a connection to open;
+    # initially 60.
+    # If the connection is not made in the given interval,
+    # an exception is raised.
     attr_accessor :open_timeout
 
-    # Number of seconds to wait for one block to be read (via one read(2)
-    # call). Any number may be used, including Floats for fractional
-    # seconds. If the HTTP object cannot read data in this many seconds,
-    # it raises a Net::ReadTimeout exception. The default value is 60 seconds.
+    # Returns the numeric (\Integer or \Float) number of seconds
+    # to wait for one block to be read (via one read(2) call);
+    # see #read_timeout=.
     attr_reader :read_timeout
 
-    # Number of seconds to wait for one block to be written (via one write(2)
-    # call). Any number may be used, including Floats for fractional
-    # seconds. If the HTTP object cannot write data in this many seconds,
-    # it raises a Net::WriteTimeout exception. The default value is 60 seconds.
-    # Net::WriteTimeout is not raised on Windows.
+    # Returns the numeric (\Integer or \Float) number of seconds
+    # to wait for one block to be written (via one write(2) call);
+    # see #write_timeout=.
     attr_reader :write_timeout
 
-    # Maximum number of times to retry an idempotent request in case of
-    # Net::ReadTimeout, IOError, EOFError, Errno::ECONNRESET,
+    # Sets the maximum number of times to retry an idempotent request in case of
+    # \Net::ReadTimeout, IOError, EOFError, Errno::ECONNRESET,
     # Errno::ECONNABORTED, Errno::EPIPE, OpenSSL::SSL::SSLError,
     # Timeout::Error.
-    # Should be a non-negative integer number. Zero means no retries.
-    # The default value is 1.
+    # The initial value is 1.
+    #
+    # Argument +retries+ must be a non-negative numeric value:
+    #
+    #   http = Net::HTTP.new(hostname)
+    #   http.max_retries = 2   # => 2
+    #   http.max_retries       # => 2
+    #
     def max_retries=(retries)
       retries = retries.to_int
       if retries < 0
@@ -808,55 +1325,113 @@ module Net   #:nodoc:
       @max_retries = retries
     end
 
+    # Returns the maximum number of times to retry an idempotent request;
+    # see #max_retries=.
     attr_reader :max_retries
 
-    # Setter for the read_timeout attribute.
+    # Sets the read timeout, in seconds, for +self+ to integer +sec+;
+    # the initial value is 60.
+    #
+    # Argument +sec+ must be a non-negative numeric value:
+    #
+    #   http = Net::HTTP.new(hostname)
+    #   http.read_timeout # => 60
+    #   http.get('/todos/1') # => #<Net::HTTPOK 200 OK readbody=true>
+    #   http.read_timeout = 0
+    #   http.get('/todos/1') # Raises Net::ReadTimeout.
+    #
     def read_timeout=(sec)
       @socket.read_timeout = sec if @socket
       @read_timeout = sec
     end
 
-    # Setter for the write_timeout attribute.
+    # Sets the write timeout, in seconds, for +self+ to integer +sec+;
+    # the initial value is 60.
+    #
+    # Argument +sec+ must be a non-negative numeric value:
+    #
+    #   _uri = uri.dup
+    #   _uri.path = '/posts'
+    #   body = 'bar' * 200000
+    #   data = <<EOF
+    #   {"title": "foo", "body": "#{body}", "userId": "1"}
+    #   EOF
+    #   headers = {'content-type': 'application/json'}
+    #   http = Net::HTTP.new(hostname)
+    #   http.write_timeout # => 60
+    #   http.post(_uri.path, data, headers)
+    #   # => #<Net::HTTPCreated 201 Created readbody=true>
+    #   http.write_timeout = 0
+    #   http.post(_uri.path, data, headers) # Raises Net::WriteTimeout.
+    #
     def write_timeout=(sec)
       @socket.write_timeout = sec if @socket
       @write_timeout = sec
     end
 
-    # Seconds to wait for 100 Continue response. If the HTTP object does not
-    # receive a response in this many seconds it sends the request body. The
-    # default value is +nil+.
+    # Returns the continue timeout value;
+    # see continue_timeout=.
     attr_reader :continue_timeout
 
-    # Setter for the continue_timeout attribute.
+    # Sets the continue timeout value,
+    # which is the number of seconds to wait for an expected 100 Continue response.
+    # If the \HTTP object does not receive a response in this many seconds
+    # it sends the request body.
     def continue_timeout=(sec)
       @socket.continue_timeout = sec if @socket
       @continue_timeout = sec
     end
 
-    # Seconds to reuse the connection of the previous request.
-    # If the idle time is less than this Keep-Alive Timeout,
-    # Net::HTTP reuses the TCP/IP socket used by the previous communication.
-    # The default value is 2 seconds.
+    # Sets or returns the numeric (\Integer or \Float) number of seconds
+    # to keep the connection open after a request is sent;
+    # initially 2.
+    # If a new request is made during the given interval,
+    # the still-open connection is used;
+    # otherwise the connection will have been closed
+    # and a new connection is opened.
     attr_accessor :keep_alive_timeout
 
-    # Returns true if the HTTP session has been started.
+    # Sets or returns whether to ignore end-of-file when reading a response body
+    # with <tt>Content-Length</tt> headers;
+    # initially +true+.
+    attr_accessor :ignore_eof
+
+    # Returns +true+ if the \HTTP session has been started:
+    #
+    #   http = Net::HTTP.new(hostname)
+    #   http.started? # => false
+    #   http.start
+    #   http.started? # => true
+    #   http.finish # => nil
+    #   http.started? # => false
+    #
+    #   Net::HTTP.start(hostname) do |http|
+    #     http.started?
+    #   end # => true
+    #   http.started? # => false
+    #
     def started?
       @started
     end
 
     alias active? started?   #:nodoc: obsolete
 
+    # Sets or returns whether to close the connection when the response is empty;
+    # initially +false+.
     attr_accessor :close_on_empty_response
 
-    # Returns true if SSL/TLS is being used with HTTP.
+    # Returns +true+ if +self+ uses SSL, +false+ otherwise.
+    # See Net::HTTP#use_ssl=.
     def use_ssl?
       @use_ssl
     end
 
-    # Turn on/off SSL.
-    # This flag must be set before starting session.
-    # If you change use_ssl value after session started,
-    # a Net::HTTP object raises IOError.
+    # Sets whether a new session is to use
+    # {Transport Layer Security}[https://en.wikipedia.org/wiki/Transport_Layer_Security]:
+    #
+    # Raises IOError if attempting to change during a session.
+    #
+    # Raises OpenSSL::SSL::SSLError if the port is not an HTTPS port.
     def use_ssl=(flag)
       flag = flag ? true : false
       if started? and @use_ssl != flag
@@ -881,7 +1456,7 @@ module Net   #:nodoc:
       :@verify_depth,
       :@verify_mode,
       :@verify_hostname,
-    ]
+    ] # :nodoc:
     SSL_ATTRIBUTES = [
       :ca_file,
       :ca_path,
@@ -898,64 +1473,67 @@ module Net   #:nodoc:
       :verify_depth,
       :verify_mode,
       :verify_hostname,
-    ]
+    ] # :nodoc:
 
-    # Sets path of a CA certification file in PEM format.
-    #
-    # The file can contain several CA certificates.
+    # Sets or returns the path to a CA certification file in PEM format.
     attr_accessor :ca_file
 
-    # Sets path of a CA certification directory containing certifications in
-    # PEM format.
+    # Sets or returns the path of to CA directory
+    # containing certification files in PEM format.
     attr_accessor :ca_path
 
-    # Sets an OpenSSL::X509::Certificate object as client certificate.
-    # (This method is appeared in Michal Rokos's OpenSSL extension).
+    # Sets or returns the OpenSSL::X509::Certificate object
+    # to be used for client certification.
     attr_accessor :cert
 
-    # Sets the X509::Store to verify peer certificate.
+    # Sets or returns the X509::Store to be used for verifying peer certificate.
     attr_accessor :cert_store
 
-    # Sets the available ciphers.  See OpenSSL::SSL::SSLContext#ciphers=
+    # Sets or returns the available SSL ciphers.
+    # See {OpenSSL::SSL::SSLContext#ciphers=}[rdoc-ref:OpenSSL::SSL::SSLContext#ciphers-3D].
     attr_accessor :ciphers
 
-    # Sets the extra X509 certificates to be added to the certificate chain.
-    # See OpenSSL::SSL::SSLContext#extra_chain_cert=
+    # Sets or returns the extra X509 certificates to be added to the certificate chain.
+    # See {OpenSSL::SSL::SSLContext#add_certificate}[rdoc-ref:OpenSSL::SSL::SSLContext#add_certificate].
     attr_accessor :extra_chain_cert
 
-    # Sets an OpenSSL::PKey::RSA or OpenSSL::PKey::DSA object.
-    # (This method is appeared in Michal Rokos's OpenSSL extension.)
+    # Sets or returns the OpenSSL::PKey::RSA or OpenSSL::PKey::DSA object.
     attr_accessor :key
 
-    # Sets the SSL timeout seconds.
+    # Sets or returns the SSL timeout seconds.
     attr_accessor :ssl_timeout
 
-    # Sets the SSL version.  See OpenSSL::SSL::SSLContext#ssl_version=
+    # Sets or returns the SSL version.
+    # See {OpenSSL::SSL::SSLContext#ssl_version=}[rdoc-ref:OpenSSL::SSL::SSLContext#ssl_version-3D].
     attr_accessor :ssl_version
 
-    # Sets the minimum SSL version.  See OpenSSL::SSL::SSLContext#min_version=
+    # Sets or returns the minimum SSL version.
+    # See {OpenSSL::SSL::SSLContext#min_version=}[rdoc-ref:OpenSSL::SSL::SSLContext#min_version-3D].
     attr_accessor :min_version
 
-    # Sets the maximum SSL version.  See OpenSSL::SSL::SSLContext#max_version=
+    # Sets or returns the maximum SSL version.
+    # See {OpenSSL::SSL::SSLContext#max_version=}[rdoc-ref:OpenSSL::SSL::SSLContext#max_version-3D].
     attr_accessor :max_version
 
-    # Sets the verify callback for the server certification verification.
+    # Sets or returns the callback for the server certification verification.
     attr_accessor :verify_callback
 
-    # Sets the maximum depth for the certificate chain verification.
+    # Sets or returns the maximum depth for the certificate chain verification.
     attr_accessor :verify_depth
 
-    # Sets the flags for server the certification verification at beginning of
-    # SSL/TLS session.
-    #
+    # Sets or returns the flags for server the certification verification
+    # at the beginning of the SSL/TLS session.
     # OpenSSL::SSL::VERIFY_NONE or OpenSSL::SSL::VERIFY_PEER are acceptable.
     attr_accessor :verify_mode
 
-    # Sets to check the server certificate is valid for the hostname.
-    # See OpenSSL::SSL::SSLContext#verify_hostname=
+    # Sets or returns whether to verify that the server certificate is valid
+    # for the hostname.
+    # See {OpenSSL::SSL::SSLContext#verify_hostname=}[rdoc-ref:OpenSSL::SSL::SSLContext#attribute-i-verify_mode].
     attr_accessor :verify_hostname
 
-    # Returns the X.509 certificates the server presented.
+    # Returns the X509 certificate chain (an array of strings)
+    # for the session's socket peer,
+    # or +nil+ if none.
     def peer_cert
       if not use_ssl? or not @socket
         return nil
@@ -963,14 +1541,26 @@ module Net   #:nodoc:
       @socket.io.peer_cert
     end
 
-    # Opens a TCP connection and HTTP session.
+    # Starts an \HTTP session.
     #
-    # When this method is called with a block, it passes the Net::HTTP
-    # object to the block, and closes the TCP connection and HTTP session
-    # after the block has been executed.
+    # Without a block, returns +self+:
     #
-    # When called with a block, it returns the return value of the
-    # block; otherwise, it returns self.
+    #   http = Net::HTTP.new(hostname)
+    #   # => #<Net::HTTP jsonplaceholder.typicode.com:80 open=false>
+    #   http.start
+    #   # => #<Net::HTTP jsonplaceholder.typicode.com:80 open=true>
+    #   http.started? # => true
+    #   http.finish
+    #
+    # With a block, calls the block with +self+,
+    # finishes the session when the block exits,
+    # and returns the block's value:
+    #
+    #   http.start do |http|
+    #     http
+    #   end
+    #   # => #<Net::HTTP jsonplaceholder.typicode.com:80 open=false>
+    #   http.started? # => false
     #
     def start  # :yield: http
       raise IOError, 'HTTP session already opened' if @started
@@ -1008,13 +1598,14 @@ module Net   #:nodoc:
       end
 
       debug "opening connection to #{conn_addr}:#{conn_port}..."
-      begin
-        s = Socket.tcp conn_addr, conn_port, @local_host, @local_port, connect_timeout: @open_timeout
-      rescue => e
-        e = Net::OpenTimeout.new(e) if e.is_a?(Errno::ETIMEDOUT) #for compatibility with previous versions
-        raise e, "Failed to open TCP connection to " +
-          "#{conn_addr}:#{conn_port} (#{e.message})"
-      end
+      s = Timeout.timeout(@open_timeout, Net::OpenTimeout) {
+        begin
+          TCPSocket.open(conn_addr, conn_port, @local_host, @local_port)
+        rescue => e
+          raise e, "Failed to open TCP connection to " +
+            "#{conn_addr}:#{conn_port} (#{e.message})"
+        end
+      }
       s.setsockopt(Socket::IPPROTO_TCP, Socket::TCP_NODELAY, 1)
       debug "opened"
       if use_ssl?
@@ -1023,8 +1614,8 @@ module Net   #:nodoc:
                                       write_timeout: @write_timeout,
                                       continue_timeout: @continue_timeout,
                                       debug_output: @debug_output)
-          buf = "CONNECT #{conn_address}:#{@port} HTTP/#{HTTPVersion}\r\n"
-          buf << "Host: #{@address}:#{@port}\r\n"
+          buf = +"CONNECT #{conn_address}:#{@port} HTTP/#{HTTPVersion}\r\n" \
+            "Host: #{@address}:#{@port}\r\n"
           if proxy_user
             credential = ["#{proxy_user}:#{proxy_pass}"].pack('m0')
             buf << "Proxy-Authorization: Basic #{credential}\r\n"
@@ -1046,10 +1637,14 @@ module Net   #:nodoc:
           end
         end
         @ssl_context.set_params(ssl_parameters)
-        @ssl_context.session_cache_mode =
-          OpenSSL::SSL::SSLContext::SESSION_CACHE_CLIENT |
-          OpenSSL::SSL::SSLContext::SESSION_CACHE_NO_INTERNAL_STORE
-        @ssl_context.session_new_cb = proc {|sock, sess| @ssl_session = sess }
+        unless @ssl_context.session_cache_mode.nil? # a dummy method on JRuby
+          @ssl_context.session_cache_mode =
+              OpenSSL::SSL::SSLContext::SESSION_CACHE_CLIENT |
+                  OpenSSL::SSL::SSLContext::SESSION_CACHE_NO_INTERNAL_STORE
+        end
+        if @ssl_context.respond_to?(:session_new_cb) # not implemented under JRuby
+          @ssl_context.session_new_cb = proc {|sock, sess| @ssl_session = sess }
+        end
 
         # Still do the post_connection_check below even if connecting
         # to IP address
@@ -1101,8 +1696,15 @@ module Net   #:nodoc:
     end
     private :on_connect
 
-    # Finishes the HTTP session and closes the TCP connection.
-    # Raises IOError if the session has not been started.
+    # Finishes the \HTTP session:
+    #
+    #   http = Net::HTTP.new(hostname)
+    #   http.start
+    #   http.started? # => true
+    #   http.finish   # => nil
+    #   http.started? # => false
+    #
+    # Raises IOError if not in a session.
     def finish
       raise IOError, 'HTTP session not yet started' unless started?
       do_finish
@@ -1129,12 +1731,12 @@ module Net   #:nodoc:
     @proxy_user = nil
     @proxy_pass = nil
 
-    # Creates an HTTP proxy class which behaves like Net::HTTP, but
+    # Creates an \HTTP proxy class which behaves like \Net::HTTP, but
     # performs all access via the specified proxy.
     #
     # This class is obsolete.  You may pass these same parameters directly to
-    # Net::HTTP.new.  See Net::HTTP.new for details of the arguments.
-    def HTTP.Proxy(p_addr = :ENV, p_port = nil, p_user = nil, p_pass = nil)
+    # \Net::HTTP.new.  See Net::HTTP.new for details of the arguments.
+    def HTTP.Proxy(p_addr = :ENV, p_port = nil, p_user = nil, p_pass = nil) #:nodoc:
       return self unless p_addr
 
       Class.new(self) {
@@ -1156,31 +1758,37 @@ module Net   #:nodoc:
     end
 
     class << HTTP
-      # returns true if self is a class which was created by HTTP::Proxy.
+      # Returns true if self is a class which was created by HTTP::Proxy.
       def proxy_class?
         defined?(@is_proxy_class) ? @is_proxy_class : false
       end
 
-      # Address of proxy host. If Net::HTTP does not use a proxy, nil.
+      # Returns the address of the proxy host, or +nil+ if none;
+      # see Net::HTTP@Proxy+Server.
       attr_reader :proxy_address
 
-      # Port number of proxy host. If Net::HTTP does not use a proxy, nil.
+      # Returns the port number of the proxy host, or +nil+ if none;
+      # see Net::HTTP@Proxy+Server.
       attr_reader :proxy_port
 
-      # User name for accessing proxy. If Net::HTTP does not use a proxy, nil.
+      # Returns the user name for accessing the proxy, or +nil+ if none;
+      # see Net::HTTP@Proxy+Server.
       attr_reader :proxy_user
 
-      # User password for accessing proxy. If Net::HTTP does not use a proxy,
-      # nil.
+      # Returns the password for accessing the proxy, or +nil+ if none;
+      # see Net::HTTP@Proxy+Server.
       attr_reader :proxy_pass
     end
 
-    # True if requests for this connection will be proxied
+    # Returns +true+ if a proxy server is defined, +false+ otherwise;
+    # see {Proxy Server}[rdoc-ref:Net::HTTP@Proxy+Server].
     def proxy?
       !!(@proxy_from_env ? proxy_uri : @proxy_address)
     end
 
-    # True if the proxy for this connection is determined from the environment
+    # Returns +true+ if the proxy server is defined in the environment,
+    # +false+ otherwise;
+    # see {Proxy Server}[rdoc-ref:Net::HTTP@Proxy+Server].
     def proxy_from_env?
       @proxy_from_env
     end
@@ -1189,12 +1797,13 @@ module Net   #:nodoc:
     def proxy_uri # :nodoc:
       return if @proxy_uri == false
       @proxy_uri ||= URI::HTTP.new(
-        "http".freeze, nil, address, port, nil, nil, nil, nil, nil
+        "http", nil, address, port, nil, nil, nil, nil, nil
       ).find_proxy || false
       @proxy_uri || nil
     end
 
-    # The address of the proxy server, if one is configured.
+    # Returns the address of the proxy server, if defined, +nil+ otherwise;
+    # see {Proxy Server}[rdoc-ref:Net::HTTP@Proxy+Server].
     def proxy_address
       if @proxy_from_env then
         proxy_uri&.hostname
@@ -1203,7 +1812,8 @@ module Net   #:nodoc:
       end
     end
 
-    # The port of the proxy server, if one is configured.
+    # Returns the port number of the proxy server, if defined, +nil+ otherwise;
+    # see {Proxy Server}[rdoc-ref:Net::HTTP@Proxy+Server].
     def proxy_port
       if @proxy_from_env then
         proxy_uri&.port
@@ -1212,16 +1822,10 @@ module Net   #:nodoc:
       end
     end
 
-    # [Bug #12921]
-    if /linux|freebsd|darwin/ =~ RUBY_PLATFORM
-      ENVIRONMENT_VARIABLE_IS_MULTIUSER_SAFE = true
-    else
-      ENVIRONMENT_VARIABLE_IS_MULTIUSER_SAFE = false
-    end
-
-    # The username of the proxy server, if one is configured.
+    # Returns the user name of the proxy server, if defined, +nil+ otherwise;
+    # see {Proxy Server}[rdoc-ref:Net::HTTP@Proxy+Server].
     def proxy_user
-      if ENVIRONMENT_VARIABLE_IS_MULTIUSER_SAFE && @proxy_from_env
+      if @proxy_from_env
         user = proxy_uri&.user
         unescape(user) if user
       else
@@ -1229,9 +1833,10 @@ module Net   #:nodoc:
       end
     end
 
-    # The password of the proxy server, if one is configured.
+    # Returns the password of the proxy server, if defined, +nil+ otherwise;
+    # see {Proxy Server}[rdoc-ref:Net::HTTP@Proxy+Server].
     def proxy_pass
-      if ENVIRONMENT_VARIABLE_IS_MULTIUSER_SAFE && @proxy_from_env
+      if @proxy_from_env
         pass = proxy_uri&.password
         unescape(pass) if pass
       else
@@ -1277,45 +1882,38 @@ module Net   #:nodoc:
 
     public
 
-    # Retrieves data from +path+ on the connected-to host which may be an
-    # absolute path String or a URI to extract the path from.
+    # :call-seq:
+    #    get(path, initheader = nil) {|res| ... }
+    #
+    # Sends a GET request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
+    #
+    # The request is based on the Net::HTTP::Get object
+    # created from string +path+ and initial headers hash +initheader+.
     #
-    # +initheader+ must be a Hash like { 'Accept' => '*/*', ... },
-    # and it defaults to an empty hash.
-    # If +initheader+ doesn't have the key 'accept-encoding', then
-    # a value of "gzip;q=1.0,deflate;q=0.6,identity;q=0.3" is used,
-    # so that gzip compression is used in preference to deflate
-    # compression, which is used in preference to no compression.
-    # Ruby doesn't have libraries to support the compress (Lempel-Ziv)
-    # compression, so that is not supported.  The intent of this is
-    # to reduce bandwidth by default.   If this routine sets up
-    # compression, then it does the decompression also, removing
-    # the header as well to prevent confusion.  Otherwise
-    # it leaves the body as it found it.
+    # With a block given, calls the block with the response body:
     #
-    # This method returns a Net::HTTPResponse object.
+    #   http = Net::HTTP.new(hostname)
+    #   http.get('/todos/1') do |res|
+    #     p res
+    #   end # => #<Net::HTTPOK 200 OK readbody=true>
+    #
+    # Output:
     #
-    # If called with a block, yields each fragment of the
-    # entity body in turn as a string as it is read from
-    # the socket.  Note that in this case, the returned response
-    # object will *not* contain a (meaningful) body.
+    #   "{\n  \"userId\": 1,\n  \"id\": 1,\n  \"title\": \"delectus aut autem\",\n  \"completed\": false\n}"
     #
-    # +dest+ argument is obsolete.
-    # It still works but you must not use it.
+    # With no block given, simply returns the response object:
     #
-    # This method never raises an exception.
+    #   http.get('/') # => #<Net::HTTPOK 200 OK readbody=true>
     #
-    #     response = http.get('/index.html')
+    # Related:
     #
-    #     # using block
-    #     File.open('result.txt', 'w') {|f|
-    #       http.get('/~foo/') do |str|
-    #         f.write str
-    #       end
-    #     }
+    # - Net::HTTP::Get: request class for \HTTP method GET.
+    # - Net::HTTP.get: sends GET request, returns response body.
     #
     def get(path, initheader = nil, dest = nil, &block) # :yield: +body_segment+
       res = nil
+
       request(Get.new(path, initheader)) {|r|
         r.read_body dest, &block
         res = r
@@ -1323,198 +1921,312 @@ module Net   #:nodoc:
       res
     end
 
-    # Gets only the header from +path+ on the connected-to host.
-    # +header+ is a Hash like { 'Accept' => '*/*', ... }.
-    #
-    # This method returns a Net::HTTPResponse object.
+    # Sends a HEAD request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
     #
-    # This method never raises an exception.
+    # The request is based on the Net::HTTP::Head object
+    # created from string +path+ and initial headers hash +initheader+:
     #
-    #     response = nil
-    #     Net::HTTP.start('some.www.server', 80) {|http|
-    #       response = http.head('/index.html')
-    #     }
-    #     p response['content-type']
+    #   res = http.head('/todos/1') # => #<Net::HTTPOK 200 OK readbody=true>
+    #   res.body                    # => nil
+    #   res.to_hash.take(3)
+    #   # =>
+    #   [["date", ["Wed, 15 Feb 2023 15:25:42 GMT"]],
+    #    ["content-type", ["application/json; charset=utf-8"]],
+    #    ["connection", ["close"]]]
     #
     def head(path, initheader = nil)
       request(Head.new(path, initheader))
     end
 
-    # Posts +data+ (must be a String) to +path+. +header+ must be a Hash
-    # like { 'Accept' => '*/*', ... }.
+    # :call-seq:
+    #    post(path, data, initheader = nil) {|res| ... }
+    #
+    # Sends a POST request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
     #
-    # This method returns a Net::HTTPResponse object.
+    # The request is based on the Net::HTTP::Post object
+    # created from string +path+, string +data+, and initial headers hash +initheader+.
     #
-    # If called with a block, yields each fragment of the
-    # entity body in turn as a string as it is read from
-    # the socket.  Note that in this case, the returned response
-    # object will *not* contain a (meaningful) body.
+    # With a block given, calls the block with the response body:
+    #
+    #   data = '{"userId": 1, "id": 1, "title": "delectus aut autem", "completed": false}'
+    #   http = Net::HTTP.new(hostname)
+    #   http.post('/todos', data) do |res|
+    #     p res
+    #   end # => #<Net::HTTPCreated 201 Created readbody=true>
     #
-    # +dest+ argument is obsolete.
-    # It still works but you must not use it.
+    # Output:
     #
-    # This method never raises exception.
+    #   "{\n  \"{\\\"userId\\\": 1, \\\"id\\\": 1, \\\"title\\\": \\\"delectus aut autem\\\", \\\"completed\\\": false}\": \"\",\n  \"id\": 201\n}"
     #
-    #     response = http.post('/cgi-bin/search.rb', 'query=foo')
+    # With no block given, simply returns the response object:
     #
-    #     # using block
-    #     File.open('result.txt', 'w') {|f|
-    #       http.post('/cgi-bin/search.rb', 'query=foo') do |str|
-    #         f.write str
-    #       end
-    #     }
+    #   http.post('/todos', data) # => #<Net::HTTPCreated 201 Created readbody=true>
     #
-    # You should set Content-Type: header field for POST.
-    # If no Content-Type: field given, this method uses
-    # "application/x-www-form-urlencoded" by default.
+    # Related:
+    #
+    # - Net::HTTP::Post: request class for \HTTP method POST.
+    # - Net::HTTP.post: sends POST request, returns response body.
     #
     def post(path, data, initheader = nil, dest = nil, &block) # :yield: +body_segment+
       send_entity(path, data, initheader, dest, Post, &block)
     end
 
-    # Sends a PATCH request to the +path+ and gets a response,
-    # as an HTTPResponse object.
+    # :call-seq:
+    #    patch(path, data, initheader = nil) {|res| ... }
+    #
+    # Sends a PATCH request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
+    #
+    # The request is based on the Net::HTTP::Patch object
+    # created from string +path+, string +data+, and initial headers hash +initheader+.
+    #
+    # With a block given, calls the block with the response body:
+    #
+    #   data = '{"userId": 1, "id": 1, "title": "delectus aut autem", "completed": false}'
+    #   http = Net::HTTP.new(hostname)
+    #   http.patch('/todos/1', data) do |res|
+    #     p res
+    #   end # => #<Net::HTTPOK 200 OK readbody=true>
+    #
+    # Output:
+    #
+    #   "{\n  \"userId\": 1,\n  \"id\": 1,\n  \"title\": \"delectus aut autem\",\n  \"completed\": false,\n  \"{\\\"userId\\\": 1, \\\"id\\\": 1, \\\"title\\\": \\\"delectus aut autem\\\", \\\"completed\\\": false}\": \"\"\n}"
+    #
+    # With no block given, simply returns the response object:
+    #
+    #   http.patch('/todos/1', data) # => #<Net::HTTPCreated 201 Created readbody=true>
+    #
     def patch(path, data, initheader = nil, dest = nil, &block) # :yield: +body_segment+
       send_entity(path, data, initheader, dest, Patch, &block)
     end
 
-    def put(path, data, initheader = nil)   #:nodoc:
+    # Sends a PUT request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
+    #
+    # The request is based on the Net::HTTP::Put object
+    # created from string +path+, string +data+, and initial headers hash +initheader+.
+    #
+    #   data = '{"userId": 1, "id": 1, "title": "delectus aut autem", "completed": false}'
+    #   http = Net::HTTP.new(hostname)
+    #   http.put('/todos/1', data) # => #<Net::HTTPOK 200 OK readbody=true>
+    #
+    def put(path, data, initheader = nil)
       request(Put.new(path, initheader), data)
     end
 
-    # Sends a PROPPATCH request to the +path+ and gets a response,
-    # as an HTTPResponse object.
+    # Sends a PROPPATCH request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
+    #
+    # The request is based on the Net::HTTP::Proppatch object
+    # created from string +path+, string +body+, and initial headers hash +initheader+.
+    #
+    #   data = '{"userId": 1, "id": 1, "title": "delectus aut autem", "completed": false}'
+    #   http = Net::HTTP.new(hostname)
+    #   http.proppatch('/todos/1', data)
+    #
     def proppatch(path, body, initheader = nil)
       request(Proppatch.new(path, initheader), body)
     end
 
-    # Sends a LOCK request to the +path+ and gets a response,
-    # as an HTTPResponse object.
+    # Sends a LOCK request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
+    #
+    # The request is based on the Net::HTTP::Lock object
+    # created from string +path+, string +body+, and initial headers hash +initheader+.
+    #
+    #   data = '{"userId": 1, "id": 1, "title": "delectus aut autem", "completed": false}'
+    #   http = Net::HTTP.new(hostname)
+    #   http.lock('/todos/1', data)
+    #
     def lock(path, body, initheader = nil)
       request(Lock.new(path, initheader), body)
     end
 
-    # Sends a UNLOCK request to the +path+ and gets a response,
-    # as an HTTPResponse object.
+    # Sends an UNLOCK request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
+    #
+    # The request is based on the Net::HTTP::Unlock object
+    # created from string +path+, string +body+, and initial headers hash +initheader+.
+    #
+    #   data = '{"userId": 1, "id": 1, "title": "delectus aut autem", "completed": false}'
+    #   http = Net::HTTP.new(hostname)
+    #   http.unlock('/todos/1', data)
+    #
     def unlock(path, body, initheader = nil)
       request(Unlock.new(path, initheader), body)
     end
 
-    # Sends a OPTIONS request to the +path+ and gets a response,
-    # as an HTTPResponse object.
+    # Sends an Options request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
+    #
+    # The request is based on the Net::HTTP::Options object
+    # created from string +path+ and initial headers hash +initheader+.
+    #
+    #   http = Net::HTTP.new(hostname)
+    #   http.options('/')
+    #
     def options(path, initheader = nil)
       request(Options.new(path, initheader))
     end
 
-    # Sends a PROPFIND request to the +path+ and gets a response,
-    # as an HTTPResponse object.
+    # Sends a PROPFIND request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
+    #
+    # The request is based on the Net::HTTP::Propfind object
+    # created from string +path+, string +body+, and initial headers hash +initheader+.
+    #
+    #   data = '{"userId": 1, "id": 1, "title": "delectus aut autem", "completed": false}'
+    #   http = Net::HTTP.new(hostname)
+    #   http.propfind('/todos/1', data)
+    #
     def propfind(path, body = nil, initheader = {'Depth' => '0'})
       request(Propfind.new(path, initheader), body)
     end
 
-    # Sends a DELETE request to the +path+ and gets a response,
-    # as an HTTPResponse object.
+    # Sends a DELETE request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
+    #
+    # The request is based on the Net::HTTP::Delete object
+    # created from string +path+ and initial headers hash +initheader+.
+    #
+    #   http = Net::HTTP.new(hostname)
+    #   http.delete('/todos/1')
+    #
     def delete(path, initheader = {'Depth' => 'Infinity'})
       request(Delete.new(path, initheader))
     end
 
-    # Sends a MOVE request to the +path+ and gets a response,
-    # as an HTTPResponse object.
+    # Sends a MOVE request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
+    #
+    # The request is based on the Net::HTTP::Move object
+    # created from string +path+ and initial headers hash +initheader+.
+    #
+    #   http = Net::HTTP.new(hostname)
+    #   http.move('/todos/1')
+    #
     def move(path, initheader = nil)
       request(Move.new(path, initheader))
     end
 
-    # Sends a COPY request to the +path+ and gets a response,
-    # as an HTTPResponse object.
+    # Sends a COPY request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
+    #
+    # The request is based on the Net::HTTP::Copy object
+    # created from string +path+ and initial headers hash +initheader+.
+    #
+    #   http = Net::HTTP.new(hostname)
+    #   http.copy('/todos/1')
+    #
     def copy(path, initheader = nil)
       request(Copy.new(path, initheader))
     end
 
-    # Sends a MKCOL request to the +path+ and gets a response,
-    # as an HTTPResponse object.
+    # Sends a MKCOL request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
+    #
+    # The request is based on the Net::HTTP::Mkcol object
+    # created from string +path+, string +body+, and initial headers hash +initheader+.
+    #
+    #   data = '{"userId": 1, "id": 1, "title": "delectus aut autem", "completed": false}'
+    #   http.mkcol('/todos/1', data)
+    #   http = Net::HTTP.new(hostname)
+    #
     def mkcol(path, body = nil, initheader = nil)
       request(Mkcol.new(path, initheader), body)
     end
 
-    # Sends a TRACE request to the +path+ and gets a response,
-    # as an HTTPResponse object.
+    # Sends a TRACE request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
+    #
+    # The request is based on the Net::HTTP::Trace object
+    # created from string +path+ and initial headers hash +initheader+.
+    #
+    #   http = Net::HTTP.new(hostname)
+    #   http.trace('/todos/1')
+    #
     def trace(path, initheader = nil)
       request(Trace.new(path, initheader))
     end
 
-    # Sends a GET request to the +path+.
-    # Returns the response as a Net::HTTPResponse object.
+    # Sends a GET request to the server;
+    # forms the response into a Net::HTTPResponse object.
     #
-    # When called with a block, passes an HTTPResponse object to the block.
-    # The body of the response will not have been read yet;
-    # the block can process it using HTTPResponse#read_body,
-    # if desired.
+    # The request is based on the Net::HTTP::Get object
+    # created from string +path+ and initial headers hash +initheader+.
     #
-    # Returns the response.
+    # With no block given, returns the response object:
+    #
+    #   http = Net::HTTP.new(hostname)
+    #   http.request_get('/todos') # => #<Net::HTTPOK 200 OK readbody=true>
     #
-    # This method never raises Net::* exceptions.
+    # With a block given, calls the block with the response object
+    # and returns the response object:
     #
-    #     response = http.request_get('/index.html')
-    #     # The entity body is already read in this case.
-    #     p response['content-type']
-    #     puts response.body
+    #   http.request_get('/todos') do |res|
+    #     p res
+    #   end # => #<Net::HTTPOK 200 OK readbody=true>
     #
-    #     # Using a block
-    #     http.request_get('/index.html') {|response|
-    #       p response['content-type']
-    #       response.read_body do |str|   # read body now
-    #         print str
-    #       end
-    #     }
+    # Output:
+    #
+    #   #<Net::HTTPOK 200 OK readbody=false>
     #
     def request_get(path, initheader = nil, &block) # :yield: +response+
       request(Get.new(path, initheader), &block)
     end
 
-    # Sends a HEAD request to the +path+ and returns the response
-    # as a Net::HTTPResponse object.
-    #
-    # Returns the response.
+    # Sends a HEAD request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
     #
-    # This method never raises Net::* exceptions.
+    # The request is based on the Net::HTTP::Head object
+    # created from string +path+ and initial headers hash +initheader+.
     #
-    #     response = http.request_head('/index.html')
-    #     p response['content-type']
+    #   http = Net::HTTP.new(hostname)
+    #   http.head('/todos/1') # => #<Net::HTTPOK 200 OK readbody=true>
     #
     def request_head(path, initheader = nil, &block)
       request(Head.new(path, initheader), &block)
     end
 
-    # Sends a POST request to the +path+.
+    # Sends a POST request to the server;
+    # forms the response into a Net::HTTPResponse object.
     #
-    # Returns the response as a Net::HTTPResponse object.
+    # The request is based on the Net::HTTP::Post object
+    # created from string +path+, string +data+, and initial headers hash +initheader+.
     #
-    # When called with a block, the block is passed an HTTPResponse
-    # object.  The body of that response will not have been read yet;
-    # the block can process it using HTTPResponse#read_body, if desired.
+    # With no block given, returns the response object:
     #
-    # Returns the response.
+    #   http = Net::HTTP.new(hostname)
+    #   http.post('/todos', 'xyzzy')
+    #   # => #<Net::HTTPCreated 201 Created readbody=true>
+    #
+    # With a block given, calls the block with the response body
+    # and returns the response object:
     #
-    # This method never raises Net::* exceptions.
+    #   http.post('/todos', 'xyzzy') do |res|
+    #     p res
+    #   end # => #<Net::HTTPCreated 201 Created readbody=true>
     #
-    #     # example
-    #     response = http.request_post('/cgi-bin/nice.rb', 'datadatadata...')
-    #     p response.status
-    #     puts response.body          # body is already read in this case
+    # Output:
     #
-    #     # using block
-    #     http.request_post('/cgi-bin/nice.rb', 'datadatadata...') {|response|
-    #       p response.status
-    #       p response['content-type']
-    #       response.read_body do |str|   # read body now
-    #         print str
-    #       end
-    #     }
+    #   "{\n  \"xyzzy\": \"\",\n  \"id\": 201\n}"
     #
     def request_post(path, data, initheader = nil, &block) # :yield: +response+
       request Post.new(path, initheader), data, &block
     end
 
+    # Sends a PUT request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
+    #
+    # The request is based on the Net::HTTP::Put object
+    # created from string +path+, string +data+, and initial headers hash +initheader+.
+    #
+    #   http = Net::HTTP.new(hostname)
+    #   http.put('/todos/1', 'xyzzy')
+    #   # => #<Net::HTTPOK 200 OK readbody=true>
+    #
     def request_put(path, data, initheader = nil, &block)   #:nodoc:
       request Put.new(path, initheader), data, &block
     end
@@ -1524,16 +2236,25 @@ module Net   #:nodoc:
     alias post2  request_post   #:nodoc: obsolete
     alias put2   request_put    #:nodoc: obsolete
 
-
-    # Sends an HTTP request to the HTTP server.
-    # Also sends a DATA string if +data+ is given.
+    # Sends an \HTTP request to the server;
+    # returns an instance of a subclass of Net::HTTPResponse.
     #
-    # Returns a Net::HTTPResponse object.
+    # The request is based on the Net::HTTPRequest object
+    # created from string +path+, string +data+, and initial headers hash +header+.
+    # That object is an instance of the
+    # {subclass of Net::HTTPRequest}[rdoc-ref:Net::HTTPRequest@Request+Subclasses],
+    # that corresponds to the given uppercase string +name+,
+    # which must be
+    # an {HTTP request method}[https://en.wikipedia.org/wiki/HTTP#Request_methods]
+    # or a {WebDAV request method}[https://en.wikipedia.org/wiki/WebDAV#Implementation].
     #
-    # This method never raises Net::* exceptions.
+    # Examples:
     #
-    #    response = http.send_request('GET', '/index.html')
-    #    puts response.body
+    #   http = Net::HTTP.new(hostname)
+    #   http.send_request('GET', '/todos/1')
+    #   # => #<Net::HTTPOK 200 OK readbody=true>
+    #   http.send_request('POST', '/todos', 'xyzzy')
+    #   # => #<Net::HTTPCreated 201 Created readbody=true>
     #
     def send_request(name, path, data = nil, header = nil)
       has_response_body = name != 'HEAD'
@@ -1541,20 +2262,35 @@ module Net   #:nodoc:
       request r, data
     end
 
-    # Sends an HTTPRequest object +req+ to the HTTP server.
+    # Sends the given request +req+ to the server;
+    # forms the response into a Net::HTTPResponse object.
+    #
+    # The given +req+ must be an instance of a
+    # {subclass of Net::HTTPRequest}[rdoc-ref:Net::HTTPRequest@Request+Subclasses].
+    # Argument +body+ should be given only if needed for the request.
+    #
+    # With no block given, returns the response object:
+    #
+    #   http = Net::HTTP.new(hostname)
+    #
+    #   req = Net::HTTP::Get.new('/todos/1')
+    #   http.request(req)
+    #   # => #<Net::HTTPOK 200 OK readbody=true>
+    #
+    #   req = Net::HTTP::Post.new('/todos')
+    #   http.request(req, 'xyzzy')
+    #   # => #<Net::HTTPCreated 201 Created readbody=true>
     #
-    # If +req+ is a Net::HTTP::Post or Net::HTTP::Put request containing
-    # data, the data is also sent. Providing data for a Net::HTTP::Head or
-    # Net::HTTP::Get request results in an ArgumentError.
+    # With a block given, calls the block with the response and returns the response:
     #
-    # Returns an HTTPResponse object.
+    #   req = Net::HTTP::Get.new('/todos/1')
+    #   http.request(req) do |res|
+    #     p res
+    #   end # => #<Net::HTTPOK 200 OK readbody=true>
     #
-    # When called with a block, passes an HTTPResponse object to the block.
-    # The body of the response will not have been read yet;
-    # the block can process it using HTTPResponse#read_body,
-    # if desired.
+    # Output:
     #
-    # This method never raises Net::* exceptions.
+    #   #<Net::HTTPOK 200 OK readbody=false>
     #
     def request(req, body = nil, &block)  # :yield: +response+
       unless started?
@@ -1606,6 +2342,7 @@ module Net   #:nodoc:
             res = HTTPResponse.read_new(@socket)
             res.decode_content = req.decode_content
             res.body_encoding = @response_body_encoding
+            res.ignore_eof = @ignore_eof
           end while res.kind_of?(HTTPInformation)
 
           res.uri = req.uri
diff --git a/lib/net/http/backward.rb b/lib/net/http/backward.rb
index 691e41e4f1..b44577edbd 100644
--- a/lib/net/http/backward.rb
+++ b/lib/net/http/backward.rb
@@ -1,4 +1,4 @@
-# frozen_string_literal: false
+# frozen_string_literal: true
 # for backward compatibility
 
 # :enddoc:
diff --git a/lib/net/http/exceptions.rb b/lib/net/http/exceptions.rb
index da5f7a70fc..ceec8f7b0a 100644
--- a/lib/net/http/exceptions.rb
+++ b/lib/net/http/exceptions.rb
@@ -1,33 +1,34 @@
-# frozen_string_literal: false
-# Net::HTTP exception class.
-# You cannot use Net::HTTPExceptions directly; instead, you must use
-# its subclasses.
-module Net::HTTPExceptions
-  def initialize(msg, res)   #:nodoc:
-    super msg
-    @response = res
+# frozen_string_literal: true
+module Net
+  # Net::HTTP exception class.
+  # You cannot use Net::HTTPExceptions directly; instead, you must use
+  # its subclasses.
+  module HTTPExceptions
+    def initialize(msg, res)   #:nodoc:
+      super msg
+      @response = res
+    end
+    attr_reader :response
+    alias data response    #:nodoc: obsolete
   end
-  attr_reader :response
-  alias data response    #:nodoc: obsolete
-end
-class Net::HTTPError < Net::ProtocolError
-  include Net::HTTPExceptions
-end
-class Net::HTTPRetriableError < Net::ProtoRetriableError
-  include Net::HTTPExceptions
-end
-class Net::HTTPServerException < Net::ProtoServerError
-  # We cannot use the name "HTTPServerError", it is the name of the response.
-  include Net::HTTPExceptions
-end
 
-# for compatibility
-Net::HTTPClientException = Net::HTTPServerException
+  class HTTPError < ProtocolError
+    include HTTPExceptions
+  end
 
-class Net::HTTPFatalError < Net::ProtoFatalError
-  include Net::HTTPExceptions
-end
+  class HTTPRetriableError < ProtoRetriableError
+    include HTTPExceptions
+  end
 
-module Net
+  class HTTPClientException < ProtoServerError
+    include HTTPExceptions
+  end
+
+  class HTTPFatalError < ProtoFatalError
+    include HTTPExceptions
+  end
+
+  # We cannot use the name "HTTPServerError", it is the name of the response.
+  HTTPServerException = HTTPClientException # :nodoc:
   deprecate_constant(:HTTPServerException)
 end
diff --git a/lib/net/http/generic_request.rb b/lib/net/http/generic_request.rb
index 313de6ac92..44e329a0c8 100644
--- a/lib/net/http/generic_request.rb
+++ b/lib/net/http/generic_request.rb
@@ -1,24 +1,29 @@
-# frozen_string_literal: false
-# HTTPGenericRequest is the parent of the Net::HTTPRequest class.
-# Do not use this directly; use a subclass of Net::HTTPRequest.
+# frozen_string_literal: true
 #
-# Mixes in the Net::HTTPHeader module to provide easier access to HTTP headers.
+# \HTTPGenericRequest is the parent of the Net::HTTPRequest class.
+#
+# Do not use this directly; instead, use a subclass of Net::HTTPRequest.
+#
+# == About the Examples
+#
+# :include: doc/net-http/examples.rdoc
 #
 class Net::HTTPGenericRequest
 
   include Net::HTTPHeader
 
-  def initialize(m, reqbody, resbody, uri_or_path, initheader = nil)
+  def initialize(m, reqbody, resbody, uri_or_path, initheader = nil) # :nodoc:
     @method = m
     @request_has_body = reqbody
     @response_has_body = resbody
 
     if URI === uri_or_path then
       raise ArgumentError, "not an HTTP URI" unless URI::HTTP === uri_or_path
-      raise ArgumentError, "no host component for URI" unless uri_or_path.hostname
+      hostname = uri_or_path.hostname
+      raise ArgumentError, "no host component for URI" unless (hostname && hostname.length > 0)
       @uri = uri_or_path.dup
       host = @uri.hostname.dup
-      host << ":".freeze << @uri.port.to_s if @uri.port != @uri.default_port
+      host << ":" << @uri.port.to_s if @uri.port != @uri.default_port
       @path = uri_or_path.request_uri
       raise ArgumentError, "no HTTP request path given" unless @path
     else
@@ -52,15 +57,47 @@ class Net::HTTPGenericRequest
     @body_data = nil
   end
 
+  # Returns the string method name for the request:
+  #
+  #   Net::HTTP::Get.new(uri).method  # => "GET"
+  #   Net::HTTP::Post.new(uri).method # => "POST"
+  #
   attr_reader :method
+
+  # Returns the string path for the request:
+  #
+  #   Net::HTTP::Get.new(uri).path # => "/"
+  #   Net::HTTP::Post.new('example.com').path # => "example.com"
+  #
   attr_reader :path
+
+  # Returns the URI object for the request, or +nil+ if none:
+  #
+  #   Net::HTTP::Get.new(uri).uri
+  #   # => #<URI::HTTPS https://jsonplaceholder.typicode.com/>
+  #   Net::HTTP::Get.new('example.com').uri # => nil
+  #
   attr_reader :uri
 
-  # Automatically set to false if the user sets the Accept-Encoding header.
-  # This indicates they wish to handle Content-encoding in responses
-  # themselves.
+  # Returns +false+ if the request's header <tt>'Accept-Encoding'</tt>
+  # has been set manually or deleted
+  # (indicating that the user intends to handle encoding in the response),
+  # +true+ otherwise:
+  #
+  #   req = Net::HTTP::Get.new(uri) # => #<Net::HTTP::Get GET>
+  #   req['Accept-Encoding']        # => "gzip;q=1.0,deflate;q=0.6,identity;q=0.3"
+  #   req.decode_content            # => true
+  #   req['Accept-Encoding'] = 'foo'
+  #   req.decode_content            # => false
+  #   req.delete('Accept-Encoding')
+  #   req.decode_content            # => false
+  #
   attr_reader :decode_content
 
+  # Returns a string representation of the request:
+  #
+  #   Net::HTTP::Post.new(uri).inspect # => "#<Net::HTTP::Post POST>"
+  #
   def inspect
     "\#<#{self.class} #{@method}>"
   end
@@ -75,21 +112,45 @@ class Net::HTTPGenericRequest
     super key, val
   end
 
+  # Returns whether the request may have a body:
+  #
+  #   Net::HTTP::Post.new(uri).request_body_permitted? # => true
+  #   Net::HTTP::Get.new(uri).request_body_permitted?  # => false
+  #
   def request_body_permitted?
     @request_has_body
   end
 
+  # Returns whether the response may have a body:
+  #
+  #   Net::HTTP::Post.new(uri).response_body_permitted? # => true
+  #   Net::HTTP::Head.new(uri).response_body_permitted? # => false
+  #
   def response_body_permitted?
     @response_has_body
   end
 
-  def body_exist?
+  def body_exist? # :nodoc:
     warn "Net::HTTPRequest#body_exist? is obsolete; use response_body_permitted?", uplevel: 1 if $VERBOSE
     response_body_permitted?
   end
 
+  # Returns the string body for the request, or +nil+ if there is none:
+  #
+  #   req = Net::HTTP::Post.new(uri)
+  #   req.body # => nil
+  #   req.body = '{"title": "foo","body": "bar","userId": 1}'
+  #   req.body # => "{\"title\": \"foo\",\"body\": \"bar\",\"userId\": 1}"
+  #
   attr_reader :body
 
+  # Sets the body for the request:
+  #
+  #   req = Net::HTTP::Post.new(uri)
+  #   req.body # => nil
+  #   req.body = '{"title": "foo","body": "bar","userId": 1}'
+  #   req.body # => "{\"title\": \"foo\",\"body\": \"bar\",\"userId\": 1}"
+  #
   def body=(str)
     @body = str
     @body_stream = nil
@@ -97,8 +158,24 @@ class Net::HTTPGenericRequest
     str
   end
 
+  # Returns the body stream object for the request, or +nil+ if there is none:
+  #
+  #   req = Net::HTTP::Post.new(uri)          # => #<Net::HTTP::Post POST>
+  #   req.body_stream                         # => nil
+  #   require 'stringio'
+  #   req.body_stream = StringIO.new('xyzzy') # => #<StringIO:0x0000027d1e5affa8>
+  #   req.body_stream                         # => #<StringIO:0x0000027d1e5affa8>
+  #
   attr_reader :body_stream
 
+  # Sets the body stream for the request:
+  #
+  #   req = Net::HTTP::Post.new(uri)          # => #<Net::HTTP::Post POST>
+  #   req.body_stream                         # => nil
+  #   require 'stringio'
+  #   req.body_stream = StringIO.new('xyzzy') # => #<StringIO:0x0000027d1e5affa8>
+  #   req.body_stream                         # => #<StringIO:0x0000027d1e5affa8>
+  #
   def body_stream=(input)
     @body = nil
     @body_stream = input
@@ -135,15 +212,15 @@ class Net::HTTPGenericRequest
     return unless @uri
 
     if ssl
-      scheme = 'https'.freeze
+      scheme = 'https'
       klass = URI::HTTPS
     else
-      scheme = 'http'.freeze
+      scheme = 'http'
       klass = URI::HTTP
     end
 
     if host = self['host']
-      host.sub!(/:.*/m, ''.freeze)
+      host.sub!(/:.*/m, '')
     elsif host = @uri.host
     else
      host = addr
@@ -239,7 +316,7 @@ class Net::HTTPGenericRequest
     boundary ||= SecureRandom.urlsafe_base64(40)
     chunked_p = chunked?
 
-    buf = ''
+    buf = +''
     params.each do |key, value, h={}|
       key = quote_string(key, charset)
       filename =
@@ -324,7 +401,7 @@ class Net::HTTPGenericRequest
     if /[\r\n]/ =~ reqline
       raise ArgumentError, "A Request-Line must not contain CR or LF"
     end
-    buf = ""
+    buf = +''
     buf << reqline << "\r\n"
     each_capitalized do |k,v|
       buf << "#{k}: #{v}\r\n"
diff --git a/lib/net/http/header.rb b/lib/net/http/header.rb
index a8901e79cb..6660c8075a 100644
--- a/lib/net/http/header.rb
+++ b/lib/net/http/header.rb
@@ -1,16 +1,188 @@
-# frozen_string_literal: false
-# The HTTPHeader module defines methods for reading and writing
-# HTTP headers.
+# frozen_string_literal: true
 #
-# It is used as a mixin by other classes, to provide hash-like
-# access to HTTP header values. Unlike raw hash access, HTTPHeader
-# provides access via case-insensitive keys. It also provides
-# methods for accessing commonly-used HTTP header values in more
-# convenient formats.
+# The \HTTPHeader module provides access to \HTTP headers.
+#
+# The module is included in:
+#
+# - Net::HTTPGenericRequest (and therefore Net::HTTPRequest).
+# - Net::HTTPResponse.
+#
+# The headers are a hash-like collection of key/value pairs called _fields_.
+#
+# == Request and Response Fields
+#
+# Headers may be included in:
+#
+# - A Net::HTTPRequest object:
+#   the object's headers will be sent with the request.
+#   Any fields may be defined in the request;
+#   see {Setters}[rdoc-ref:Net::HTTPHeader@Setters].
+# - A Net::HTTPResponse object:
+#   the objects headers are usually those returned from the host.
+#   Fields may be retrieved from the object;
+#   see {Getters}[rdoc-ref:Net::HTTPHeader@Getters]
+#   and {Iterators}[rdoc-ref:Net::HTTPHeader@Iterators].
+#
+# Exactly which fields should be sent or expected depends on the host;
+# see:
+#
+# - {Request fields}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#Request_fields].
+# - {Response fields}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#Response_fields].
+#
+# == About the Examples
+#
+# :include: doc/net-http/examples.rdoc
+#
+# == Fields
+#
+# A header field is a key/value pair.
+#
+# === Field Keys
+#
+# A field key may be:
+#
+# - A string: Key <tt>'Accept'</tt> is treated as if it were
+#   <tt>'Accept'.downcase</tt>;  i.e., <tt>'accept'</tt>.
+# - A symbol: Key <tt>:Accept</tt> is treated as if it were
+#   <tt>:Accept.to_s.downcase</tt>;  i.e., <tt>'accept'</tt>.
+#
+# Examples:
+#
+#   req = Net::HTTP::Get.new(uri)
+#   req[:accept]  # => "*/*"
+#   req['Accept'] # => "*/*"
+#   req['ACCEPT'] # => "*/*"
+#
+#   req['accept'] = 'text/html'
+#   req[:accept] = 'text/html'
+#   req['ACCEPT'] = 'text/html'
+#
+# === Field Values
+#
+# A field value may be returned as an array of strings or as a string:
+#
+# - These methods return field values as arrays:
+#
+#   - #get_fields: Returns the array value for the given key,
+#     or +nil+ if it does not exist.
+#   - #to_hash: Returns a hash of all header fields:
+#     each key is a field name; its value is the array value for the field.
+#
+# - These methods return field values as string;
+#   the string value for a field is equivalent to
+#   <tt>self[key.downcase.to_s].join(', '))</tt>:
+#
+#   - #[]: Returns the string value for the given key,
+#     or +nil+ if it does not exist.
+#   - #fetch: Like #[], but accepts a default value
+#     to be returned if the key does not exist.
+#
+# The field value may be set:
+#
+# - #[]=: Sets the value for the given key;
+#   the given value may be a string, a symbol, an array, or a hash.
+# - #add_field: Adds a given value to a value for the given key
+#   (not overwriting the existing value).
+# - #delete: Deletes the field for the given key.
+#
+# Example field values:
+#
+# - \String:
+#
+#     req['Accept'] = 'text/html' # => "text/html"
+#     req['Accept']               # => "text/html"
+#     req.get_fields('Accept')    # => ["text/html"]
+#
+# - \Symbol:
+#
+#     req['Accept'] = :text    # => :text
+#     req['Accept']            # => "text"
+#     req.get_fields('Accept') # => ["text"]
+#
+# - Simple array:
+#
+#     req[:foo] = %w[bar baz bat]
+#     req[:foo]            # => "bar, baz, bat"
+#     req.get_fields(:foo) # => ["bar", "baz", "bat"]
+#
+# - Simple hash:
+#
+#     req[:foo] = {bar: 0, baz: 1, bat: 2}
+#     req[:foo]            # => "bar, 0, baz, 1, bat, 2"
+#     req.get_fields(:foo) # => ["bar", "0", "baz", "1", "bat", "2"]
+#
+# - Nested:
+#
+#     req[:foo] = [%w[bar baz], {bat: 0, bam: 1}]
+#     req[:foo]            # => "bar, baz, bat, 0, bam, 1"
+#     req.get_fields(:foo) # => ["bar", "baz", "bat", "0", "bam", "1"]
+#
+#     req[:foo] = {bar: %w[baz bat], bam: {bah: 0, bad: 1}}
+#     req[:foo]            # => "bar, baz, bat, bam, bah, 0, bad, 1"
+#     req.get_fields(:foo) # => ["bar", "baz", "bat", "bam", "bah", "0", "bad", "1"]
+#
+# == Convenience Methods
+#
+# Various convenience methods retrieve values, set values, query values,
+# set form values, or iterate over fields.
+#
+# === Setters
+#
+# \Method #[]= can set any field, but does little to validate the new value;
+# some of the other setter methods provide some validation:
+#
+# - #[]=: Sets the string or array value for the given key.
+# - #add_field: Creates or adds to the array value for the given key.
+# - #basic_auth: Sets the string authorization header for <tt>'Authorization'</tt>.
+# - #content_length=: Sets the integer length for field <tt>'Content-Length</tt>.
+# - #content_type=: Sets the string value for field <tt>'Content-Type'</tt>.
+# - #proxy_basic_auth: Sets the string authorization header for <tt>'Proxy-Authorization'</tt>.
+# - #set_range: Sets the value for field <tt>'Range'</tt>.
+#
+# === Form Setters
+#
+# - #set_form: Sets an HTML form data set.
+# - #set_form_data: Sets header fields and a body from HTML form data.
+#
+# === Getters
+#
+# \Method #[] can retrieve the value of any field that exists,
+# but always as a string;
+# some of the other getter methods return something different
+# from the simple string value:
+#
+# - #[]: Returns the string field value for the given key.
+# - #content_length: Returns the integer value of field <tt>'Content-Length'</tt>.
+# - #content_range: Returns the Range value of field <tt>'Content-Range'</tt>.
+# - #content_type: Returns the string value of field <tt>'Content-Type'</tt>.
+# - #fetch: Returns the string field value for the given key.
+# - #get_fields: Returns the array field value for the given +key+.
+# - #main_type: Returns first part of the string value of field <tt>'Content-Type'</tt>.
+# - #sub_type: Returns second part of the string value of field <tt>'Content-Type'</tt>.
+# - #range: Returns an array of Range objects of field <tt>'Range'</tt>, or +nil+.
+# - #range_length: Returns the integer length of the range given in field <tt>'Content-Range'</tt>.
+# - #type_params: Returns the string parameters for <tt>'Content-Type'</tt>.
+#
+# === Queries
+#
+# - #chunked?: Returns whether field <tt>'Transfer-Encoding'</tt> is set to <tt>'chunked'</tt>.
+# - #connection_close?: Returns whether field <tt>'Connection'</tt> is set to <tt>'close'</tt>.
+# - #connection_keep_alive?: Returns whether field <tt>'Connection'</tt> is set to <tt>'keep-alive'</tt>.
+# - #key?: Returns whether a given key exists.
+#
+# === Iterators
+#
+# - #each_capitalized: Passes each field capitalized-name/value pair to the block.
+# - #each_capitalized_name: Passes each capitalized field name to the block.
+# - #each_header: Passes each field name/value pair to the block.
+# - #each_name: Passes each field name to the block.
+# - #each_value: Passes each string field value to the block.
 #
 module Net::HTTPHeader
+  MAX_KEY_LENGTH = 1024
+  MAX_FIELD_LENGTH = 65536
 
-  def initialize_http_header(initheader)
+  def initialize_http_header(initheader) #:nodoc:
     @header = {}
     return unless initheader
     initheader.each do |key, value|
@@ -19,6 +191,12 @@ module Net::HTTPHeader
         warn "net/http: nil HTTP header: #{key}", uplevel: 3 if $VERBOSE
       else
         value = value.strip # raise error for invalid byte sequences
+        if key.to_s.bytesize > MAX_KEY_LENGTH
+          raise ArgumentError, "too long (#{key.bytesize} bytes) header: #{key[0, 30].inspect}..."
+        end
+        if value.to_s.bytesize > MAX_FIELD_LENGTH
+          raise ArgumentError, "header #{key} has too long field value: #{value.bytesize}"
+        end
         if value.count("\r\n") > 0
           raise ArgumentError, "header #{key} has field value #{value.inspect}, this cannot include CR/LF"
         end
@@ -33,14 +211,32 @@ module Net::HTTPHeader
 
   alias length size   #:nodoc: obsolete
 
-  # Returns the header field corresponding to the case-insensitive key.
-  # For example, a key of "Content-Type" might return "text/html"
+  # Returns the string field value for the case-insensitive field +key+,
+  # or +nil+ if there is no such key;
+  # see {Fields}[rdoc-ref:Net::HTTPHeader@Fields]:
+  #
+  #   res = Net::HTTP.get_response(hostname, '/todos/1')
+  #   res['Connection'] # => "keep-alive"
+  #   res['Nosuch']     # => nil
+  #
+  # Note that some field values may be retrieved via convenience methods;
+  # see {Getters}[rdoc-ref:Net::HTTPHeader@Getters].
   def [](key)
     a = @header[key.downcase.to_s] or return nil
     a.join(', ')
   end
 
-  # Sets the header field corresponding to the case-insensitive key.
+  # Sets the value for the case-insensitive +key+ to +val+,
+  # overwriting the previous value if the field exists;
+  # see {Fields}[rdoc-ref:Net::HTTPHeader@Fields]:
+  #
+  #   req = Net::HTTP::Get.new(uri)
+  #   req['Accept'] # => "*/*"
+  #   req['Accept'] = 'text/html'
+  #   req['Accept'] # => "text/html"
+  #
+  # Note that some field values may be set via convenience methods;
+  # see {Setters}[rdoc-ref:Net::HTTPHeader@Setters].
   def []=(key, val)
     unless val
       @header.delete key.downcase.to_s
@@ -49,20 +245,18 @@ module Net::HTTPHeader
     set_field(key, val)
   end
 
-  # [Ruby 1.8.3]
-  # Adds a value to a named header field, instead of replacing its value.
-  # Second argument +val+ must be a String.
-  # See also #[]=, #[] and #get_fields.
+  # Adds value +val+ to the value array for field +key+ if the field exists;
+  # creates the field with the given +key+ and +val+ if it does not exist.
+  # see {Fields}[rdoc-ref:Net::HTTPHeader@Fields]:
   #
-  #   request.add_field 'X-My-Header', 'a'
-  #   p request['X-My-Header']              #=> "a"
-  #   p request.get_fields('X-My-Header')   #=> ["a"]
-  #   request.add_field 'X-My-Header', 'b'
-  #   p request['X-My-Header']              #=> "a, b"
-  #   p request.get_fields('X-My-Header')   #=> ["a", "b"]
-  #   request.add_field 'X-My-Header', 'c'
-  #   p request['X-My-Header']              #=> "a, b, c"
-  #   p request.get_fields('X-My-Header')   #=> ["a", "b", "c"]
+  #   req = Net::HTTP::Get.new(uri)
+  #   req.add_field('Foo', 'bar')
+  #   req['Foo']            # => "bar"
+  #   req.add_field('Foo', 'baz')
+  #   req['Foo']            # => "bar, baz"
+  #   req.add_field('Foo', %w[baz bam])
+  #   req['Foo']            # => "bar, baz, baz, bam"
+  #   req.get_fields('Foo') # => ["bar", "baz", "baz", "bam"]
   #
   def add_field(key, val)
     stringified_downcased_key = key.downcase.to_s
@@ -101,16 +295,13 @@ module Net::HTTPHeader
     end
   end
 
-  # [Ruby 1.8.3]
-  # Returns an array of header field strings corresponding to the
-  # case-insensitive +key+.  This method allows you to get duplicated
-  # header fields without any processing.  See also #[].
+  # Returns the array field value for the given +key+,
+  # or +nil+ if there is no such field;
+  # see {Fields}[rdoc-ref:Net::HTTPHeader@Fields]:
   #
-  #   p response.get_fields('Set-Cookie')
-  #     #=> ["session=al98axx; expires=Fri, 31-Dec-1999 23:58:23",
-  #          "query=rubyscript; expires=Fri, 31-Dec-1999 23:58:23"]
-  #   p response['Set-Cookie']
-  #     #=> "session=al98axx; expires=Fri, 31-Dec-1999 23:58:23, query=rubyscript; expires=Fri, 31-Dec-1999 23:58:23"
+  #   res = Net::HTTP.get_response(hostname, '/todos/1')
+  #   res.get_fields('Connection') # => ["keep-alive"]
+  #   res.get_fields('Nosuch')     # => nil
   #
   def get_fields(key)
     stringified_downcased_key = key.downcase.to_s
@@ -118,24 +309,58 @@ module Net::HTTPHeader
     @header[stringified_downcased_key].dup
   end
 
-  # Returns the header field corresponding to the case-insensitive key.
-  # Returns the default value +args+, or the result of the block, or
-  # raises an IndexError if there's no header field named +key+
-  # See Hash#fetch
+  # call-seq:
+  #   fetch(key, default_val = nil) {|key| ... } -> object
+  #   fetch(key, default_val = nil) -> value or default_val
+  #
+  # With a block, returns the string value for +key+ if it exists;
+  # otherwise returns the value of the block;
+  # ignores the +default_val+;
+  # see {Fields}[rdoc-ref:Net::HTTPHeader@Fields]:
+  #
+  #   res = Net::HTTP.get_response(hostname, '/todos/1')
+  #
+  #   # Field exists; block not called.
+  #   res.fetch('Connection') do |value|
+  #     fail 'Cannot happen'
+  #   end # => "keep-alive"
+  #
+  #   # Field does not exist; block called.
+  #   res.fetch('Nosuch') do |value|
+  #     value.downcase
+  #   end # => "nosuch"
+  #
+  # With no block, returns the string value for +key+ if it exists;
+  # otherwise, returns +default_val+ if it was given;
+  # otherwise raises an exception:
+  #
+  #   res.fetch('Connection', 'Foo') # => "keep-alive"
+  #   res.fetch('Nosuch', 'Foo')     # => "Foo"
+  #   res.fetch('Nosuch')            # Raises KeyError.
+  #
   def fetch(key, *args, &block)   #:yield: +key+
     a = @header.fetch(key.downcase.to_s, *args, &block)
     a.kind_of?(Array) ? a.join(', ') : a
   end
 
-  # Iterates through the header names and values, passing in the name
-  # and value to the code block supplied.
+  # Calls the block with each key/value pair:
   #
-  # Returns an enumerator if no block is given.
+  #   res = Net::HTTP.get_response(hostname, '/todos/1')
+  #   res.each_header do |key, value|
+  #     p [key, value] if key.start_with?('c')
+  #   end
   #
-  # Example:
+  # Output:
   #
-  #     response.header.each_header {|key,value| puts "#{key} = #{value}" }
+  #   ["content-type", "application/json; charset=utf-8"]
+  #   ["connection", "keep-alive"]
+  #   ["cache-control", "max-age=43200"]
+  #   ["cf-cache-status", "HIT"]
+  #   ["cf-ray", "771d17e9bc542cf5-ORD"]
   #
+  # Returns an enumerator if no block is given.
+  #
+  # Net::HTTPHeader#each is an alias for Net::HTTPHeader#each_header.
   def each_header   #:yield: +key+, +value+
     block_given? or return enum_for(__method__) { @header.size }
     @header.each do |k,va|
@@ -145,10 +370,24 @@ module Net::HTTPHeader
 
   alias each each_header
 
-  # Iterates through the header names in the header, passing
-  # each header name to the code block.
+  # Calls the block with each field key:
+  #
+  #   res = Net::HTTP.get_response(hostname, '/todos/1')
+  #   res.each_key do |key|
+  #     p key if key.start_with?('c')
+  #   end
+  #
+  # Output:
+  #
+  #   "content-type"
+  #   "connection"
+  #   "cache-control"
+  #   "cf-cache-status"
+  #   "cf-ray"
   #
   # Returns an enumerator if no block is given.
+  #
+  # Net::HTTPHeader#each_name is an alias for Net::HTTPHeader#each_key.
   def each_name(&block)   #:yield: +key+
     block_given? or return enum_for(__method__) { @header.size }
     @header.each_key(&block)
@@ -156,12 +395,23 @@ module Net::HTTPHeader
 
   alias each_key each_name
 
-  # Iterates through the header names in the header, passing
-  # capitalized header names to the code block.
+  # Calls the block with each capitalized field name:
+  #
+  #   res = Net::HTTP.get_response(hostname, '/todos/1')
+  #   res.each_capitalized_name do |key|
+  #     p key if key.start_with?('C')
+  #   end
+  #
+  # Output:
   #
-  # Note that header names are capitalized systematically;
-  # capitalization may not match that used by the remote HTTP
-  # server in its response.
+  #   "Content-Type"
+  #   "Connection"
+  #   "Cache-Control"
+  #   "Cf-Cache-Status"
+  #   "Cf-Ray"
+  #
+  # The capitalization is system-dependent;
+  # see {Case Mapping}[rdoc-ref:case_mapping.rdoc].
   #
   # Returns an enumerator if no block is given.
   def each_capitalized_name  #:yield: +key+
@@ -171,8 +421,18 @@ module Net::HTTPHeader
     end
   end
 
-  # Iterates through header values, passing each value to the
-  # code block.
+  # Calls the block with each string field value:
+  #
+  #   res = Net::HTTP.get_response(hostname, '/todos/1')
+  #   res.each_value do |value|
+  #     p value if value.start_with?('c')
+  #   end
+  #
+  # Output:
+  #
+  #   "chunked"
+  #   "cf-q-config;dur=6.0000002122251e-06"
+  #   "cloudflare"
   #
   # Returns an enumerator if no block is given.
   def each_value   #:yield: +value+
@@ -182,32 +442,45 @@ module Net::HTTPHeader
     end
   end
 
-  # Removes a header field, specified by case-insensitive key.
+  # Removes the header for the given case-insensitive +key+
+  # (see {Fields}[rdoc-ref:Net::HTTPHeader@Fields]);
+  # returns the deleted value, or +nil+ if no such field exists:
+  #
+  #   req = Net::HTTP::Get.new(uri)
+  #   req.delete('Accept') # => ["*/*"]
+  #   req.delete('Nosuch') # => nil
+  #
   def delete(key)
     @header.delete(key.downcase.to_s)
   end
 
-  # true if +key+ header exists.
+  # Returns +true+ if the field for the case-insensitive +key+ exists, +false+ otherwise:
+  #
+  #   req = Net::HTTP::Get.new(uri)
+  #   req.key?('Accept') # => true
+  #   req.key?('Nosuch') # => false
+  #
   def key?(key)
     @header.key?(key.downcase.to_s)
   end
 
-  # Returns a Hash consisting of header names and array of values.
-  # e.g.
-  # {"cache-control" => ["private"],
-  #  "content-type" => ["text/html"],
-  #  "date" => ["Wed, 22 Jun 2005 22:11:50 GMT"]}
+  # Returns a hash of the key/value pairs:
+  #
+  #   req = Net::HTTP::Get.new(uri)
+  #   req.to_hash
+  #   # =>
+  #   {"accept-encoding"=>["gzip;q=1.0,deflate;q=0.6,identity;q=0.3"],
+  #    "accept"=>["*/*"],
+  #    "user-agent"=>["Ruby"],
+  #    "host"=>["jsonplaceholder.typicode.com"]}
+  #
   def to_hash
     @header.dup
   end
 
-  # As for #each_header, except the keys are provided in capitalized form.
+  # Like #each_header, but the keys are returned in capitalized form.
   #
-  # Note that header names are capitalized systematically;
-  # capitalization may not match that used by the remote HTTP
-  # server in its response.
-  #
-  # Returns an enumerator if no block is given.
+  # Net::HTTPHeader#canonical_each is an alias for Net::HTTPHeader#each_capitalized.
   def each_capitalized
     block_given? or return enum_for(__method__) { @header.size }
     @header.each do |k,v|
@@ -222,8 +495,17 @@ module Net::HTTPHeader
   end
   private :capitalize
 
-  # Returns an Array of Range objects which represent the Range:
-  # HTTP header field, or +nil+ if there is no such header.
+  # Returns an array of Range objects that represent
+  # the value of field <tt>'Range'</tt>,
+  # or +nil+ if there is no such field;
+  # see {Range request header}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#range-request-header]:
+  #
+  #   req = Net::HTTP::Get.new(uri)
+  #   req['Range'] = 'bytes=0-99,200-299,400-499'
+  #   req.range # => [0..99, 200..299, 400..499]
+  #   req.delete('Range')
+  #   req.range # # => nil
+  #
   def range
     return nil unless @header['range']
 
@@ -266,14 +548,31 @@ module Net::HTTPHeader
     result
   end
 
-  # Sets the HTTP Range: header.
-  # Accepts either a Range object as a single argument,
-  # or a beginning index and a length from that index.
-  # Example:
+  # call-seq:
+  #   set_range(length) -> length
+  #   set_range(offset, length) -> range
+  #   set_range(begin..length) -> range
+  #
+  # Sets the value for field <tt>'Range'</tt>;
+  # see {Range request header}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#range-request-header]:
+  #
+  # With argument +length+:
+  #
+  #   req = Net::HTTP::Get.new(uri)
+  #   req.set_range(100)      # => 100
+  #   req['Range']            # => "bytes=0-99"
   #
-  #   req.range = (0..1023)
-  #   req.set_range 0, 1023
+  # With arguments +offset+ and +length+:
   #
+  #   req.set_range(100, 100) # => 100...200
+  #   req['Range']            # => "bytes=100-199"
+  #
+  # With argument +range+:
+  #
+  #   req.set_range(100..199) # => 100..199
+  #   req['Range']            # => "bytes=100-199"
+  #
+  # Net::HTTPHeader#range= is an alias for Net::HTTPHeader#set_range.
   def set_range(r, e = nil)
     unless r
       @header.delete 'range'
@@ -305,8 +604,15 @@ module Net::HTTPHeader
 
   alias range= set_range
 
-  # Returns an Integer object which represents the HTTP Content-Length:
-  # header field, or +nil+ if that field was not provided.
+  # Returns the value of field <tt>'Content-Length'</tt> as an integer,
+  # or +nil+ if there is no such field;
+  # see {Content-Length request header}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#content-length-request-header]:
+  #
+  #   res = Net::HTTP.get_response(hostname, '/nosuch/1')
+  #   res.content_length # => 2
+  #   res = Net::HTTP.get_response(hostname, '/todos/1')
+  #   res.content_length # => nil
+  #
   def content_length
     return nil unless key?('Content-Length')
     len = self['Content-Length'].slice(/\d+/) or
@@ -314,6 +620,20 @@ module Net::HTTPHeader
     len.to_i
   end
 
+  # Sets the value of field <tt>'Content-Length'</tt> to the given numeric;
+  # see {Content-Length response header}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#content-length-response-header]:
+  #
+  #   _uri = uri.dup
+  #   hostname = _uri.hostname           # => "jsonplaceholder.typicode.com"
+  #   _uri.path = '/posts'               # => "/posts"
+  #   req = Net::HTTP::Post.new(_uri)    # => #<Net::HTTP::Post POST>
+  #   req.body = '{"title": "foo","body": "bar","userId": 1}'
+  #   req.content_length = req.body.size # => 42
+  #   req.content_type = 'application/json'
+  #   res = Net::HTTP.start(hostname) do |http|
+  #     http.request(req)
+  #   end # => #<Net::HTTPCreated 201 Created readbody=true>
+  #
   def content_length=(len)
     unless len
       @header.delete 'content-length'
@@ -322,53 +642,99 @@ module Net::HTTPHeader
     @header['content-length'] = [len.to_i.to_s]
   end
 
-  # Returns "true" if the "transfer-encoding" header is present and
-  # set to "chunked".  This is an HTTP/1.1 feature, allowing
-  # the content to be sent in "chunks" without at the outset
-  # stating the entire content length.
+  # Returns +true+ if field <tt>'Transfer-Encoding'</tt>
+  # exists and has value <tt>'chunked'</tt>,
+  # +false+ otherwise;
+  # see {Transfer-Encoding response header}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#transfer-encoding-response-header]:
+  #
+  #   res = Net::HTTP.get_response(hostname, '/todos/1')
+  #   res['Transfer-Encoding'] # => "chunked"
+  #   res.chunked?             # => true
+  #
   def chunked?
     return false unless @header['transfer-encoding']
     field = self['Transfer-Encoding']
     (/(?:\A|[^\-\w])chunked(?![\-\w])/i =~ field) ? true : false
   end
 
-  # Returns a Range object which represents the value of the Content-Range:
-  # header field.
-  # For a partial entity body, this indicates where this fragment
-  # fits inside the full entity body, as range of byte offsets.
+  # Returns a Range object representing the value of field
+  # <tt>'Content-Range'</tt>, or +nil+ if no such field exists;
+  # see {Content-Range response header}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#content-range-response-header]:
+  #
+  #   res = Net::HTTP.get_response(hostname, '/todos/1')
+  #   res['Content-Range'] # => nil
+  #   res['Content-Range'] = 'bytes 0-499/1000'
+  #   res['Content-Range'] # => "bytes 0-499/1000"
+  #   res.content_range    # => 0..499
+  #
   def content_range
     return nil unless @header['content-range']
-    m = %r<bytes\s+(\d+)-(\d+)/(\d+|\*)>i.match(self['Content-Range']) or
+    m = %r<\A\s*(\w+)\s+(\d+)-(\d+)/(\d+|\*)>.match(self['Content-Range']) or
         raise Net::HTTPHeaderSyntaxError, 'wrong Content-Range format'
-    m[1].to_i .. m[2].to_i
+    return unless m[1] == 'bytes'
+    m[2].to_i .. m[3].to_i
   end
 
-  # The length of the range represented in Content-Range: header.
+  # Returns the integer representing length of the value of field
+  # <tt>'Content-Range'</tt>, or +nil+ if no such field exists;
+  # see {Content-Range response header}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#content-range-response-header]:
+  #
+  #   res = Net::HTTP.get_response(hostname, '/todos/1')
+  #   res['Content-Range'] # => nil
+  #   res['Content-Range'] = 'bytes 0-499/1000'
+  #   res.range_length     # => 500
+  #
   def range_length
     r = content_range() or return nil
     r.end - r.begin + 1
   end
 
-  # Returns a content type string such as "text/html".
-  # This method returns nil if Content-Type: header field does not exist.
+  # Returns the {media type}[https://en.wikipedia.org/wiki/Media_type]
+  # from the value of field <tt>'Content-Type'</tt>,
+  # or +nil+ if no such field exists;
+  # see {Content-Type response header}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#content-type-response-header]:
+  #
+  #   res = Net::HTTP.get_response(hostname, '/todos/1')
+  #   res['content-type'] # => "application/json; charset=utf-8"
+  #   res.content_type    # => "application/json"
+  #
   def content_type
-    return nil unless main_type()
-    if sub_type()
-    then "#{main_type()}/#{sub_type()}"
-    else main_type()
+    main = main_type()
+    return nil unless main
+
+    sub = sub_type()
+    if sub
+      "#{main}/#{sub}"
+    else
+      main
     end
   end
 
-  # Returns a content type string such as "text".
-  # This method returns nil if Content-Type: header field does not exist.
+  # Returns the leading ('type') part of the
+  # {media type}[https://en.wikipedia.org/wiki/Media_type]
+  # from the value of field <tt>'Content-Type'</tt>,
+  # or +nil+ if no such field exists;
+  # see {Content-Type response header}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#content-type-response-header]:
+  #
+  #   res = Net::HTTP.get_response(hostname, '/todos/1')
+  #   res['content-type'] # => "application/json; charset=utf-8"
+  #   res.main_type       # => "application"
+  #
   def main_type
     return nil unless @header['content-type']
     self['Content-Type'].split(';').first.to_s.split('/')[0].to_s.strip
   end
 
-  # Returns a content type string such as "html".
-  # This method returns nil if Content-Type: header field does not exist
-  # or sub-type is not given (e.g. "Content-Type: text").
+  # Returns the trailing ('subtype') part of the
+  # {media type}[https://en.wikipedia.org/wiki/Media_type]
+  # from the value of field <tt>'Content-Type'</tt>,
+  # or +nil+ if no such field exists;
+  # see {Content-Type response header}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#content-type-response-header]:
+  #
+  #   res = Net::HTTP.get_response(hostname, '/todos/1')
+  #   res['content-type'] # => "application/json; charset=utf-8"
+  #   res.sub_type        # => "json"
+  #
   def sub_type
     return nil unless @header['content-type']
     _, sub = *self['Content-Type'].split(';').first.to_s.split('/')
@@ -376,9 +742,14 @@ module Net::HTTPHeader
     sub.strip
   end
 
-  # Any parameters specified for the content type, returned as a Hash.
-  # For example, a header of Content-Type: text/html; charset=EUC-JP
-  # would result in type_params returning {'charset' => 'EUC-JP'}
+  # Returns the trailing ('parameters') part of the value of field <tt>'Content-Type'</tt>,
+  # or +nil+ if no such field exists;
+  # see {Content-Type response header}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#content-type-response-header]:
+  #
+  #   res = Net::HTTP.get_response(hostname, '/todos/1')
+  #   res['content-type'] # => "application/json; charset=utf-8"
+  #   res.type_params     # => {"charset"=>"utf-8"}
+  #
   def type_params
     result = {}
     list = self['Content-Type'].to_s.split(';')
@@ -390,29 +761,54 @@ module Net::HTTPHeader
     result
   end
 
-  # Sets the content type in an HTTP header.
-  # The +type+ should be a full HTTP content type, e.g. "text/html".
-  # The +params+ are an optional Hash of parameters to add after the
-  # content type, e.g. {'charset' => 'iso-8859-1'}
+  # Sets the value of field <tt>'Content-Type'</tt>;
+  # returns the new value;
+  # see {Content-Type request header}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#content-type-request-header]:
+  #
+  #   req = Net::HTTP::Get.new(uri)
+  #   req.set_content_type('application/json') # => ["application/json"]
+  #
+  # Net::HTTPHeader#content_type= is an alias for Net::HTTPHeader#set_content_type.
   def set_content_type(type, params = {})
     @header['content-type'] = [type + params.map{|k,v|"; #{k}=#{v}"}.join('')]
   end
 
   alias content_type= set_content_type
 
-  # Set header fields and a body from HTML form data.
-  # +params+ should be an Array of Arrays or
-  # a Hash containing HTML form data.
-  # Optional argument +sep+ means data record separator.
+  # Sets the request body to a URL-encoded string derived from argument +params+,
+  # and sets request header field <tt>'Content-Type'</tt>
+  # to <tt>'application/x-www-form-urlencoded'</tt>.
+  #
+  # The resulting request is suitable for HTTP request +POST+ or +PUT+.
+  #
+  # Argument +params+ must be suitable for use as argument +enum+ to
+  # {URI.encode_www_form}[rdoc-ref:URI.encode_www_form].
+  #
+  # With only argument +params+ given,
+  # sets the body to a URL-encoded string with the default separator <tt>'&'</tt>:
+  #
+  #   req = Net::HTTP::Post.new('example.com')
+  #
+  #   req.set_form_data(q: 'ruby', lang: 'en')
+  #   req.body            # => "q=ruby&lang=en"
+  #   req['Content-Type'] # => "application/x-www-form-urlencoded"
   #
-  # Values are URL encoded as necessary and the content-type is set to
-  # application/x-www-form-urlencoded
+  #   req.set_form_data([['q', 'ruby'], ['lang', 'en']])
+  #   req.body            # => "q=ruby&lang=en"
   #
-  # Example:
-  #    http.form_data = {"q" => "ruby", "lang" => "en"}
-  #    http.form_data = {"q" => ["ruby", "perl"], "lang" => "en"}
-  #    http.set_form_data({"q" => "ruby", "lang" => "en"}, ';')
+  #   req.set_form_data(q: ['ruby', 'perl'], lang: 'en')
+  #   req.body            # => "q=ruby&q=perl&lang=en"
   #
+  #   req.set_form_data([['q', 'ruby'], ['q', 'perl'], ['lang', 'en']])
+  #   req.body            # => "q=ruby&q=perl&lang=en"
+  #
+  # With string argument +sep+ also given,
+  # uses that string as the separator:
+  #
+  #   req.set_form_data({q: 'ruby', lang: 'en'}, '|')
+  #   req.body # => "q=ruby|lang=en"
+  #
+  # Net::HTTPHeader#form_data= is an alias for Net::HTTPHeader#set_form_data.
   def set_form_data(params, sep = '&')
     query = URI.encode_www_form(params)
     query.gsub!(/&/, sep) if sep != '&'
@@ -422,53 +818,108 @@ module Net::HTTPHeader
 
   alias form_data= set_form_data
 
-  # Set an HTML form data set.
-  # +params+ :: The form data to set, which should be an enumerable.
-  #             See below for more details.
-  # +enctype+ :: The content type to use to encode the form submission,
-  #              which should be application/x-www-form-urlencoded or
-  #              multipart/form-data.
-  # +formopt+ :: An options hash, supporting the following options:
-  #              :boundary :: The boundary of the multipart message. If
-  #                           not given, a random boundary will be used.
-  #              :charset :: The charset of the form submission. All
-  #                          field names and values of non-file fields
-  #                          should be encoded with this charset.
-  #
-  # Each item of params should respond to +each+ and yield 2-3 arguments,
-  # or an array of 2-3 elements. The arguments yielded should be:
-  #  * The name of the field.
-  #  * The value of the field, it should be a String or a File or IO-like.
-  #  * An options hash, supporting the following options, only
-  #    used for file uploads:
-  #    :filename :: The name of the file to use.
-  #    :content_type :: The content type of the uploaded file.
-  #
-  # Each item is a file field or a normal field.
-  # If +value+ is a File object or the +opt+ hash has a :filename key,
-  # the item is treated as a file field.
-  #
-  # If Transfer-Encoding is set as chunked, this sends the request using
-  # chunked encoding. Because chunked encoding is HTTP/1.1 feature,
-  # you should confirm that the server supports HTTP/1.1 before using
-  # chunked encoding.
-  #
-  # Example:
-  #    req.set_form([["q", "ruby"], ["lang", "en"]])
-  #
-  #    req.set_form({"f"=>File.open('/path/to/filename')},
-  #                 "multipart/form-data",
-  #                 charset: "UTF-8",
-  #    )
-  #
-  #    req.set_form([["f",
-  #                   File.open('/path/to/filename.bar'),
-  #                   {filename: "other-filename.foo"}
-  #                 ]],
-  #                 "multipart/form-data",
-  #    )
-  #
-  # See also RFC 2388, RFC 2616, HTML 4.01, and HTML5
+  # Stores form data to be used in a +POST+ or +PUT+ request.
+  #
+  # The form data given in +params+ consists of zero or more fields;
+  # each field is:
+  #
+  # - A scalar value.
+  # - A name/value pair.
+  # - An IO stream opened for reading.
+  #
+  # Argument +params+ should be an
+  # {Enumerable}[rdoc-ref:Enumerable@Enumerable+in+Ruby+Classes]
+  # (method <tt>params.map</tt> will be called),
+  # and is often an array or hash.
+  #
+  # First, we set up a request:
+  #
+  #   _uri = uri.dup
+  #   _uri.path ='/posts'
+  #   req = Net::HTTP::Post.new(_uri)
+  #
+  # <b>Argument +params+ As an Array</b>
+  #
+  # When +params+ is an array,
+  # each of its elements is a subarray that defines a field;
+  # the subarray may contain:
+  #
+  # - One string:
+  #
+  #     req.set_form([['foo'], ['bar'], ['baz']])
+  #
+  # - Two strings:
+  #
+  #     req.set_form([%w[foo 0], %w[bar 1], %w[baz 2]])
+  #
+  # - When argument +enctype+ (see below) is given as
+  #   <tt>'multipart/form-data'</tt>:
+  #
+  #   - A string name and an IO stream opened for reading:
+  #
+  #       require 'stringio'
+  #       req.set_form([['file', StringIO.new('Ruby is cool.')]])
+  #
+  #   - A string name, an IO stream opened for reading,
+  #     and an options hash, which may contain these entries:
+  #
+  #     - +:filename+: The name of the file to use.
+  #     - +:content_type+: The content type of the uploaded file.
+  #
+  #     Example:
+  #
+  #       req.set_form([['file', file, {filename: "other-filename.foo"}]]
+  #
+  # The various forms may be mixed:
+  #
+  #   req.set_form(['foo', %w[bar 1], ['file', file]])
+  #
+  # <b>Argument +params+ As a Hash</b>
+  #
+  # When +params+ is a hash,
+  # each of its entries is a name/value pair that defines a field:
+  #
+  # - The name is a string.
+  # - The value may be:
+  #
+  #   - +nil+.
+  #   - Another string.
+  #   - An IO stream opened for reading
+  #     (only when argument +enctype+ -- see below -- is given as
+  #     <tt>'multipart/form-data'</tt>).
+  #
+  # Examples:
+  #
+  #   # Nil-valued fields.
+  #   req.set_form({'foo' => nil, 'bar' => nil, 'baz' => nil})
+  #
+  #   # String-valued fields.
+  #   req.set_form({'foo' => 0, 'bar' => 1, 'baz' => 2})
+  #
+  #   # IO-valued field.
+  #   require 'stringio'
+  #   req.set_form({'file' => StringIO.new('Ruby is cool.')})
+  #
+  #   # Mixture of fields.
+  #   req.set_form({'foo' => nil, 'bar' => 1, 'file' => file})
+  #
+  # Optional argument +enctype+ specifies the value to be given
+  # to field <tt>'Content-Type'</tt>, and must be one of:
+  #
+  # - <tt>'application/x-www-form-urlencoded'</tt> (the default).
+  # - <tt>'multipart/form-data'</tt>;
+  #   see {RFC 7578}[https://www.rfc-editor.org/rfc/rfc7578].
+  #
+  # Optional argument +formopt+ is a hash of options
+  # (applicable only when argument +enctype+
+  # is <tt>'multipart/form-data'</tt>)
+  # that may include the following entries:
+  #
+  # - +:boundary+: The value is the boundary string for the multipart message.
+  #   If not given, the boundary is a random string.
+  #   See {Boundary}[https://www.rfc-editor.org/rfc/rfc7578#section-4.1].
+  # - +:charset+: Value is the character set for the form submission.
+  #   Field names and values of non-file fields should be encoded with this charset.
   #
   def set_form(params, enctype='application/x-www-form-urlencoded', formopt={})
     @body_data = params
@@ -484,12 +935,24 @@ module Net::HTTPHeader
     end
   end
 
-  # Set the Authorization: header for "Basic" authorization.
+  # Sets header <tt>'Authorization'</tt> using the given
+  # +account+ and +password+ strings:
+  #
+  #   req.basic_auth('my_account', 'my_password')
+  #   req['Authorization']
+  #   # => "Basic bXlfYWNjb3VudDpteV9wYXNzd29yZA=="
+  #
   def basic_auth(account, password)
     @header['authorization'] = [basic_encode(account, password)]
   end
 
-  # Set Proxy-Authorization: header for "Basic" authorization.
+  # Sets header <tt>'Proxy-Authorization'</tt> using the given
+  # +account+ and +password+ strings:
+  #
+  #   req.proxy_basic_auth('my_account', 'my_password')
+  #   req['Proxy-Authorization']
+  #   # => "Basic bXlfYWNjb3VudDpteV9wYXNzd29yZA=="
+  #
   def proxy_basic_auth(account, password)
     @header['proxy-authorization'] = [basic_encode(account, password)]
   end
@@ -499,6 +962,7 @@ module Net::HTTPHeader
   end
   private :basic_encode
 
+# Returns whether the HTTP session is to be closed.
   def connection_close?
     token = /(?:\A|,)\s*close\s*(?:\z|,)/i
     @header['connection']&.grep(token) {return true}
@@ -506,6 +970,7 @@ module Net::HTTPHeader
     false
   end
 
+# Returns whether the HTTP session is to be kept alive.
   def connection_keep_alive?
     token = /(?:\A|,)\s*keep-alive\s*(?:\z|,)/i
     @header['connection']&.grep(token) {return true}
diff --git a/lib/net/http/net-http.gemspec b/lib/net/http/net-http.gemspec
index a7f122fc0e..0021136793 100644
--- a/lib/net/http/net-http.gemspec
+++ b/lib/net/http/net-http.gemspec
@@ -2,9 +2,14 @@
 
 name = File.basename(__FILE__, ".gemspec")
 version = ["lib", Array.new(name.count("-")+1, "..").join("/")].find do |dir|
-  break File.foreach(File.join(__dir__, dir, "#{name.tr('-', '/')}.rb")) do |line|
-    /^\s*VERSION\s*=\s*"(.*)"/ =~ line and break $1
-  end rescue nil
+  file = File.join(__dir__, dir, "#{name.tr('-', '/')}.rb")
+  begin
+    break File.foreach(file, mode: "rb") do |line|
+      /^\s*VERSION\s*=\s*"(.*)"/ =~ line and break $1
+    end
+  rescue SystemCallError
+    next
+  end
 end
 
 Gem::Specification.new do |spec|
@@ -25,7 +30,7 @@ Gem::Specification.new do |spec|
   # Specify which files should be added to the gem when it is released.
   # The `git ls-files -z` loads the files in the RubyGem that have been added into git.
   spec.files         = Dir.chdir(File.expand_path('..', __FILE__)) do
-    `git ls-files -z 2>/dev/null`.split("\x0").reject { |f| f.match(%r{^(test|spec|features)/}) }
+    `git ls-files -z 2>#{IO::NULL}`.split("\x0").reject { |f| f.match(%r{\A(?:(?:test|spec|features)/|\.git)}) }
   end
   spec.bindir        = "exe"
   spec.require_paths = ["lib"]
diff --git a/lib/net/http/proxy_delta.rb b/lib/net/http/proxy_delta.rb
index a2f770ebdb..e7d30def64 100644
--- a/lib/net/http/proxy_delta.rb
+++ b/lib/net/http/proxy_delta.rb
@@ -1,4 +1,4 @@
-# frozen_string_literal: false
+# frozen_string_literal: true
 module Net::HTTP::ProxyDelta   #:nodoc: internal use only
   private
 
diff --git a/lib/net/http/request.rb b/lib/net/http/request.rb
index 1e86f3e4b4..4a138572e9 100644
--- a/lib/net/http/request.rb
+++ b/lib/net/http/request.rb
@@ -1,8 +1,76 @@
-# frozen_string_literal: false
-# HTTP request class.
-# This class wraps together the request header and the request path.
-# You cannot use this class directly. Instead, you should use one of its
-# subclasses: Net::HTTP::Get, Net::HTTP::Post, Net::HTTP::Head.
+# frozen_string_literal: true
+
+# This class is the base class for \Net::HTTP request classes.
+# The class should not be used directly;
+# instead you should use its subclasses, listed below.
+#
+# == Creating a Request
+#
+# An request object may be created with either a URI or a string hostname:
+#
+#   require 'net/http'
+#   uri = URI('https://jsonplaceholder.typicode.com/')
+#   req = Net::HTTP::Get.new(uri)          # => #<Net::HTTP::Get GET>
+#   req = Net::HTTP::Get.new(uri.hostname) # => #<Net::HTTP::Get GET>
+#
+# And with any of the subclasses:
+#
+#   req = Net::HTTP::Head.new(uri) # => #<Net::HTTP::Head HEAD>
+#   req = Net::HTTP::Post.new(uri) # => #<Net::HTTP::Post POST>
+#   req = Net::HTTP::Put.new(uri)  # => #<Net::HTTP::Put PUT>
+#   # ...
+#
+# The new instance is suitable for use as the argument to Net::HTTP#request.
+#
+# == Request Headers
+#
+# A new request object has these header fields by default:
+#
+#   req.to_hash
+#   # =>
+#   {"accept-encoding"=>["gzip;q=1.0,deflate;q=0.6,identity;q=0.3"],
+#   "accept"=>["*/*"],
+#   "user-agent"=>["Ruby"],
+#   "host"=>["jsonplaceholder.typicode.com"]}
+#
+# See:
+#
+# - {Request header Accept-Encoding}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#Accept-Encoding]
+#   and {Compression and Decompression}[rdoc-ref:Net::HTTP@Compression+and+Decompression].
+# - {Request header Accept}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#accept-request-header].
+# - {Request header User-Agent}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#user-agent-request-header].
+# - {Request header Host}[https://en.wikipedia.org/wiki/List_of_HTTP_header_fields#host-request-header].
+#
+# You can add headers or override default headers:
+#
+#   #   res = Net::HTTP::Get.new(uri, {'foo' => '0', 'bar' => '1'})
+#
+# This class (and therefore its subclasses) also includes (indirectly)
+# module Net::HTTPHeader, which gives access to its
+# {methods for setting headers}[rdoc-ref:Net::HTTPHeader@Setters].
+#
+# == Request Subclasses
+#
+# Subclasses for HTTP requests:
+#
+# - Net::HTTP::Get
+# - Net::HTTP::Head
+# - Net::HTTP::Post
+# - Net::HTTP::Put
+# - Net::HTTP::Delete
+# - Net::HTTP::Options
+# - Net::HTTP::Trace
+# - Net::HTTP::Patch
+#
+# Subclasses for WebDAV requests:
+#
+# - Net::HTTP::Propfind
+# - Net::HTTP::Proppatch
+# - Net::HTTP::Mkcol
+# - Net::HTTP::Copy
+# - Net::HTTP::Move
+# - Net::HTTP::Lock
+# - Net::HTTP::Unlock
 #
 class Net::HTTPRequest < Net::HTTPGenericRequest
   # Creates an HTTP request object for +path+.
@@ -18,4 +86,3 @@ class Net::HTTPRequest < Net::HTTPGenericRequest
           path, initheader
   end
 end
-
diff --git a/lib/net/http/requests.rb b/lib/net/http/requests.rb
index d4c80a3812..5724164205 100644
--- a/lib/net/http/requests.rb
+++ b/lib/net/http/requests.rb
@@ -1,67 +1,257 @@
-# frozen_string_literal: false
-#
+# frozen_string_literal: true
+
 # HTTP/1.1 methods --- RFC2616
-#
 
-# See Net::HTTPGenericRequest for attributes and methods.
-# See Net::HTTP for usage examples.
+# \Class for representing
+# {HTTP method GET}[https://en.wikipedia.org/w/index.php?title=Hypertext_Transfer_Protocol#GET_method]:
+#
+#   require 'net/http'
+#   uri = URI('http://example.com')
+#   hostname = uri.hostname # => "example.com"
+#   req = Net::HTTP::Get.new(uri) # => #<Net::HTTP::Get GET>
+#   res = Net::HTTP.start(hostname) do |http|
+#     http.request(req)
+#   end
+#
+# See {Request Headers}[rdoc-ref:Net::HTTPRequest@Request+Headers].
+#
+# Properties:
+#
+# - Request body: optional.
+# - Response body: yes.
+# - {Safe}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Safe_methods]: yes.
+# - {Idempotent}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Idempotent_methods]: yes.
+# - {Cacheable}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Cacheable_methods]: yes.
+#
+# Related:
+#
+# - Net::HTTP.get: sends +GET+ request, returns response body.
+# - Net::HTTP#get: sends +GET+ request, returns response object.
+#
 class Net::HTTP::Get < Net::HTTPRequest
   METHOD = 'GET'
   REQUEST_HAS_BODY  = false
   RESPONSE_HAS_BODY = true
 end
 
-# See Net::HTTPGenericRequest for attributes and methods.
-# See Net::HTTP for usage examples.
+# \Class for representing
+# {HTTP method HEAD}[https://en.wikipedia.org/w/index.php?title=Hypertext_Transfer_Protocol#HEAD_method]:
+#
+#   require 'net/http'
+#   uri = URI('http://example.com')
+#   hostname = uri.hostname # => "example.com"
+#   req = Net::HTTP::Head.new(uri) # => #<Net::HTTP::Head HEAD>
+#   res = Net::HTTP.start(hostname) do |http|
+#     http.request(req)
+#   end
+#
+# See {Request Headers}[rdoc-ref:Net::HTTPRequest@Request+Headers].
+#
+# Properties:
+#
+# - Request body: optional.
+# - Response body: no.
+# - {Safe}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Safe_methods]: yes.
+# - {Idempotent}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Idempotent_methods]: yes.
+# - {Cacheable}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Cacheable_methods]: yes.
+#
+# Related:
+#
+# - Net::HTTP#head: sends +HEAD+ request, returns response object.
+#
 class Net::HTTP::Head < Net::HTTPRequest
   METHOD = 'HEAD'
   REQUEST_HAS_BODY = false
   RESPONSE_HAS_BODY = false
 end
 
-# See Net::HTTPGenericRequest for attributes and methods.
-# See Net::HTTP for usage examples.
+# \Class for representing
+# {HTTP method POST}[https://en.wikipedia.org/w/index.php?title=Hypertext_Transfer_Protocol#POST_method]:
+#
+#   require 'net/http'
+#   uri = URI('http://example.com')
+#   hostname = uri.hostname # => "example.com"
+#   uri.path = '/posts'
+#   req = Net::HTTP::Post.new(uri) # => #<Net::HTTP::Post POST>
+#   req.body = '{"title": "foo","body": "bar","userId": 1}'
+#   req.content_type = 'application/json'
+#   res = Net::HTTP.start(hostname) do |http|
+#     http.request(req)
+#   end
+#
+# See {Request Headers}[rdoc-ref:Net::HTTPRequest@Request+Headers].
+#
+# Properties:
+#
+# - Request body: yes.
+# - Response body: yes.
+# - {Safe}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Safe_methods]: no.
+# - {Idempotent}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Idempotent_methods]: no.
+# - {Cacheable}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Cacheable_methods]: yes.
+#
+# Related:
+#
+# - Net::HTTP.post: sends +POST+ request, returns response object.
+# - Net::HTTP#post: sends +POST+ request, returns response object.
+#
 class Net::HTTP::Post < Net::HTTPRequest
   METHOD = 'POST'
   REQUEST_HAS_BODY = true
   RESPONSE_HAS_BODY = true
 end
 
-# See Net::HTTPGenericRequest for attributes and methods.
-# See Net::HTTP for usage examples.
+# \Class for representing
+# {HTTP method PUT}[https://en.wikipedia.org/w/index.php?title=Hypertext_Transfer_Protocol#PUT_method]:
+#
+#   require 'net/http'
+#   uri = URI('http://example.com')
+#   hostname = uri.hostname # => "example.com"
+#   uri.path = '/posts'
+#   req = Net::HTTP::Put.new(uri) # => #<Net::HTTP::Put PUT>
+#   req.body = '{"title": "foo","body": "bar","userId": 1}'
+#   req.content_type = 'application/json'
+#   res = Net::HTTP.start(hostname) do |http|
+#     http.request(req)
+#   end
+#
+# See {Request Headers}[rdoc-ref:Net::HTTPRequest@Request+Headers].
+#
+# Properties:
+#
+# - Request body: yes.
+# - Response body: yes.
+# - {Safe}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Safe_methods]: no.
+# - {Idempotent}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Idempotent_methods]: yes.
+# - {Cacheable}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Cacheable_methods]: no.
+#
 class Net::HTTP::Put < Net::HTTPRequest
   METHOD = 'PUT'
   REQUEST_HAS_BODY = true
   RESPONSE_HAS_BODY = true
 end
 
-# See Net::HTTPGenericRequest for attributes and methods.
-# See Net::HTTP for usage examples.
+# \Class for representing
+# {HTTP method DELETE}[https://en.wikipedia.org/w/index.php?title=Hypertext_Transfer_Protocol#DELETE_method]:
+#
+#   require 'net/http'
+#   uri = URI('http://example.com')
+#   hostname = uri.hostname # => "example.com"
+#   uri.path = '/posts/1'
+#   req = Net::HTTP::Delete.new(uri) # => #<Net::HTTP::Delete DELETE>
+#   res = Net::HTTP.start(hostname) do |http|
+#     http.request(req)
+#   end
+#
+# See {Request Headers}[rdoc-ref:Net::HTTPRequest@Request+Headers].
+#
+# Properties:
+#
+# - Request body: optional.
+# - Response body: yes.
+# - {Safe}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Safe_methods]: no.
+# - {Idempotent}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Idempotent_methods]: yes.
+# - {Cacheable}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Cacheable_methods]: no.
+#
+# Related:
+#
+# - Net::HTTP#delete: sends +DELETE+ request, returns response object.
+#
 class Net::HTTP::Delete < Net::HTTPRequest
   METHOD = 'DELETE'
   REQUEST_HAS_BODY = false
   RESPONSE_HAS_BODY = true
 end
 
-# See Net::HTTPGenericRequest for attributes and methods.
+# \Class for representing
+# {HTTP method OPTIONS}[https://en.wikipedia.org/w/index.php?title=Hypertext_Transfer_Protocol#OPTIONS_method]:
+#
+#   require 'net/http'
+#   uri = URI('http://example.com')
+#   hostname = uri.hostname # => "example.com"
+#   req = Net::HTTP::Options.new(uri) # => #<Net::HTTP::Options OPTIONS>
+#   res = Net::HTTP.start(hostname) do |http|
+#     http.request(req)
+#   end
+#
+# See {Request Headers}[rdoc-ref:Net::HTTPRequest@Request+Headers].
+#
+# Properties:
+#
+# - Request body: optional.
+# - Response body: yes.
+# - {Safe}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Safe_methods]: yes.
+# - {Idempotent}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Idempotent_methods]: yes.
+# - {Cacheable}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Cacheable_methods]: no.
+#
+# Related:
+#
+# - Net::HTTP#options: sends +OPTIONS+ request, returns response object.
+#
 class Net::HTTP::Options < Net::HTTPRequest
   METHOD = 'OPTIONS'
   REQUEST_HAS_BODY = false
   RESPONSE_HAS_BODY = true
 end
 
-# See Net::HTTPGenericRequest for attributes and methods.
+# \Class for representing
+# {HTTP method TRACE}[https://en.wikipedia.org/w/index.php?title=Hypertext_Transfer_Protocol#TRACE_method]:
+#
+#   require 'net/http'
+#   uri = URI('http://example.com')
+#   hostname = uri.hostname # => "example.com"
+#   req = Net::HTTP::Trace.new(uri) # => #<Net::HTTP::Trace TRACE>
+#   res = Net::HTTP.start(hostname) do |http|
+#     http.request(req)
+#   end
+#
+# See {Request Headers}[rdoc-ref:Net::HTTPRequest@Request+Headers].
+#
+# Properties:
+#
+# - Request body: no.
+# - Response body: yes.
+# - {Safe}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Safe_methods]: yes.
+# - {Idempotent}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Idempotent_methods]: yes.
+# - {Cacheable}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Cacheable_methods]: no.
+#
+# Related:
+#
+# - Net::HTTP#trace: sends +TRACE+ request, returns response object.
+#
 class Net::HTTP::Trace < Net::HTTPRequest
   METHOD = 'TRACE'
   REQUEST_HAS_BODY = false
   RESPONSE_HAS_BODY = true
 end
 
+# \Class for representing
+# {HTTP method PATCH}[https://en.wikipedia.org/w/index.php?title=Hypertext_Transfer_Protocol#PATCH_method]:
 #
-# PATCH method --- RFC5789
+#   require 'net/http'
+#   uri = URI('http://example.com')
+#   hostname = uri.hostname # => "example.com"
+#   uri.path = '/posts'
+#   req = Net::HTTP::Patch.new(uri) # => #<Net::HTTP::Patch PATCH>
+#   req.body = '{"title": "foo","body": "bar","userId": 1}'
+#   req.content_type = 'application/json'
+#   res = Net::HTTP.start(hostname) do |http|
+#     http.request(req)
+#   end
+#
+# See {Request Headers}[rdoc-ref:Net::HTTPRequest@Request+Headers].
+#
+# Properties:
+#
+# - Request body: yes.
+# - Response body: yes.
+# - {Safe}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Safe_methods]: no.
+# - {Idempotent}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Idempotent_methods]: no.
+# - {Cacheable}[https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol#Cacheable_methods]: no.
+#
+# Related:
+#
+# - Net::HTTP#patch: sends +PATCH+ request, returns response object.
 #
-
-# See Net::HTTPGenericRequest for attributes and methods.
 class Net::HTTP::Patch < Net::HTTPRequest
   METHOD = 'PATCH'
   REQUEST_HAS_BODY = true
@@ -72,49 +262,161 @@ end
 # WebDAV methods --- RFC2518
 #
 
-# See Net::HTTPGenericRequest for attributes and methods.
+# \Class for representing
+# {WebDAV method PROPFIND}[http://www.webdav.org/specs/rfc4918.html#METHOD_PROPFIND]:
+#
+#   require 'net/http'
+#   uri = URI('http://example.com')
+#   hostname = uri.hostname # => "example.com"
+#   req = Net::HTTP::Propfind.new(uri) # => #<Net::HTTP::Propfind PROPFIND>
+#   res = Net::HTTP.start(hostname) do |http|
+#     http.request(req)
+#   end
+#
+# See {Request Headers}[rdoc-ref:Net::HTTPRequest@Request+Headers].
+#
+# Related:
+#
+# - Net::HTTP#propfind: sends +PROPFIND+ request, returns response object.
+#
 class Net::HTTP::Propfind < Net::HTTPRequest
   METHOD = 'PROPFIND'
   REQUEST_HAS_BODY = true
   RESPONSE_HAS_BODY = true
 end
 
-# See Net::HTTPGenericRequest for attributes and methods.
+# \Class for representing
+# {WebDAV method PROPPATCH}[http://www.webdav.org/specs/rfc4918.html#METHOD_PROPPATCH]:
+#
+#   require 'net/http'
+#   uri = URI('http://example.com')
+#   hostname = uri.hostname # => "example.com"
+#   req = Net::HTTP::Proppatch.new(uri) # => #<Net::HTTP::Proppatch PROPPATCH>
+#   res = Net::HTTP.start(hostname) do |http|
+#     http.request(req)
+#   end
+#
+# See {Request Headers}[rdoc-ref:Net::HTTPRequest@Request+Headers].
+#
+# Related:
+#
+# - Net::HTTP#proppatch: sends +PROPPATCH+ request, returns response object.
+#
 class Net::HTTP::Proppatch < Net::HTTPRequest
   METHOD = 'PROPPATCH'
   REQUEST_HAS_BODY = true
   RESPONSE_HAS_BODY = true
 end
 
-# See Net::HTTPGenericRequest for attributes and methods.
+# \Class for representing
+# {WebDAV method MKCOL}[http://www.webdav.org/specs/rfc4918.html#METHOD_MKCOL]:
+#
+#   require 'net/http'
+#   uri = URI('http://example.com')
+#   hostname = uri.hostname # => "example.com"
+#   req = Net::HTTP::Mkcol.new(uri) # => #<Net::HTTP::Mkcol MKCOL>
+#   res = Net::HTTP.start(hostname) do |http|
+#     http.request(req)
+#   end
+#
+# See {Request Headers}[rdoc-ref:Net::HTTPRequest@Request+Headers].
+#
+# Related:
+#
+# - Net::HTTP#mkcol: sends +MKCOL+ request, returns response object.
+#
 class Net::HTTP::Mkcol < Net::HTTPRequest
   METHOD = 'MKCOL'
   REQUEST_HAS_BODY = true
   RESPONSE_HAS_BODY = true
 end
 
-# See Net::HTTPGenericRequest for attributes and methods.
+# \Class for representing
+# {WebDAV method COPY}[http://www.webdav.org/specs/rfc4918.html#METHOD_COPY]:
+#
+#   require 'net/http'
+#   uri = URI('http://example.com')
+#   hostname = uri.hostname # => "example.com"
+#   req = Net::HTTP::Copy.new(uri) # => #<Net::HTTP::Copy COPY>
+#   res = Net::HTTP.start(hostname) do |http|
+#     http.request(req)
+#   end
+#
+# See {Request Headers}[rdoc-ref:Net::HTTPRequest@Request+Headers].
+#
+# Related:
+#
+# - Net::HTTP#copy: sends +COPY+ request, returns response object.
+#
 class Net::HTTP::Copy < Net::HTTPRequest
   METHOD = 'COPY'
   REQUEST_HAS_BODY = false
   RESPONSE_HAS_BODY = true
 end
 
-# See Net::HTTPGenericRequest for attributes and methods.
+# \Class for representing
+# {WebDAV method MOVE}[http://www.webdav.org/specs/rfc4918.html#METHOD_MOVE]:
+#
+#   require 'net/http'
+#   uri = URI('http://example.com')
+#   hostname = uri.hostname # => "example.com"
+#   req = Net::HTTP::Move.new(uri) # => #<Net::HTTP::Move MOVE>
+#   res = Net::HTTP.start(hostname) do |http|
+#     http.request(req)
+#   end
+#
+# See {Request Headers}[rdoc-ref:Net::HTTPRequest@Request+Headers].
+#
+# Related:
+#
+# - Net::HTTP#move: sends +MOVE+ request, returns response object.
+#
 class Net::HTTP::Move < Net::HTTPRequest
   METHOD = 'MOVE'
   REQUEST_HAS_BODY = false
   RESPONSE_HAS_BODY = true
 end
 
-# See Net::HTTPGenericRequest for attributes and methods.
+# \Class for representing
+# {WebDAV method LOCK}[http://www.webdav.org/specs/rfc4918.html#METHOD_LOCK]:
+#
+#   require 'net/http'
+#   uri = URI('http://example.com')
+#   hostname = uri.hostname # => "example.com"
+#   req = Net::HTTP::Lock.new(uri) # => #<Net::HTTP::Lock LOCK>
+#   res = Net::HTTP.start(hostname) do |http|
+#     http.request(req)
+#   end
+#
+# See {Request Headers}[rdoc-ref:Net::HTTPRequest@Request+Headers].
+#
+# Related:
+#
+# - Net::HTTP#lock: sends +LOCK+ request, returns response object.
+#
 class Net::HTTP::Lock < Net::HTTPRequest
   METHOD = 'LOCK'
   REQUEST_HAS_BODY = true
   RESPONSE_HAS_BODY = true
 end
 
-# See Net::HTTPGenericRequest for attributes and methods.
+# \Class for representing
+# {WebDAV method UNLOCK}[http://www.webdav.org/specs/rfc4918.html#METHOD_UNLOCK]:
+#
+#   require 'net/http'
+#   uri = URI('http://example.com')
+#   hostname = uri.hostname # => "example.com"
+#   req = Net::HTTP::Unlock.new(uri) # => #<Net::HTTP::Unlock UNLOCK>
+#   res = Net::HTTP.start(hostname) do |http|
+#     http.request(req)
+#   end
+#
+# See {Request Headers}[rdoc-ref:Net::HTTPRequest@Request+Headers].
+#
+# Related:
+#
+# - Net::HTTP#unlock: sends +UNLOCK+ request, returns response object.
+#
 class Net::HTTP::Unlock < Net::HTTPRequest
   METHOD = 'UNLOCK'
   REQUEST_HAS_BODY = true
diff --git a/lib/net/http/response.rb b/lib/net/http/response.rb
index ecbfd42d2b..40de963868 100644
--- a/lib/net/http/response.rb
+++ b/lib/net/http/response.rb
@@ -1,20 +1,136 @@
-# frozen_string_literal: false
-# HTTP response class.
+# frozen_string_literal: true
+
+# This class is the base class for \Net::HTTP response classes.
+#
+# == About the Examples
+#
+# :include: doc/net-http/examples.rdoc
+#
+# == Returned Responses
+#
+# \Method Net::HTTP.get_response returns
+# an instance of one of the subclasses of \Net::HTTPResponse:
+#
+#   Net::HTTP.get_response(uri)
+#   # => #<Net::HTTPOK 200 OK readbody=true>
+#   Net::HTTP.get_response(hostname, '/nosuch')
+#   # => #<Net::HTTPNotFound 404 Not Found readbody=true>
+#
+# As does method Net::HTTP#request:
+#
+#   req = Net::HTTP::Get.new(uri)
+#   Net::HTTP.start(hostname) do |http|
+#     http.request(req)
+#   end # => #<Net::HTTPOK 200 OK readbody=true>
+#
+# \Class \Net::HTTPResponse includes module Net::HTTPHeader,
+# which provides access to response header values via (among others):
+#
+# - \Hash-like method <tt>[]</tt>.
+# - Specific reader methods, such as +content_type+.
+#
+# Examples:
+#
+#   res = Net::HTTP.get_response(uri) # => #<Net::HTTPOK 200 OK readbody=true>
+#   res['Content-Type']               # => "text/html; charset=UTF-8"
+#   res.content_type                  # => "text/html"
+#
+# == Response Subclasses
+#
+# \Class \Net::HTTPResponse has a subclass for each
+# {HTTP status code}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes].
+# You can look up the response class for a given code:
+#
+#   Net::HTTPResponse::CODE_TO_OBJ['200'] # => Net::HTTPOK
+#   Net::HTTPResponse::CODE_TO_OBJ['400'] # => Net::HTTPBadRequest
+#   Net::HTTPResponse::CODE_TO_OBJ['404'] # => Net::HTTPNotFound
+#
+# And you can retrieve the status code for a response object:
+#
+#   Net::HTTP.get_response(uri).code                 # => "200"
+#   Net::HTTP.get_response(hostname, '/nosuch').code # => "404"
+#
+# The response subclasses (indentation shows class hierarchy):
+#
+# - Net::HTTPUnknownResponse (for unhandled \HTTP extensions).
+#
+# - Net::HTTPInformation:
+#
+#   - Net::HTTPContinue (100)
+#   - Net::HTTPSwitchProtocol (101)
+#   - Net::HTTPProcessing (102)
+#   - Net::HTTPEarlyHints (103)
 #
-# This class wraps together the response header and the response body (the
-# entity requested).
+# - Net::HTTPSuccess:
 #
-# It mixes in the HTTPHeader module, which provides access to response
-# header values both via hash-like methods and via individual readers.
+#   - Net::HTTPOK (200)
+#   - Net::HTTPCreated (201)
+#   - Net::HTTPAccepted (202)
+#   - Net::HTTPNonAuthoritativeInformation (203)
+#   - Net::HTTPNoContent (204)
+#   - Net::HTTPResetContent (205)
+#   - Net::HTTPPartialContent (206)
+#   - Net::HTTPMultiStatus (207)
+#   - Net::HTTPAlreadyReported (208)
+#   - Net::HTTPIMUsed (226)
 #
-# Note that each possible HTTP response code defines its own
-# HTTPResponse subclass. All classes are defined under the Net module.
-# Indentation indicates inheritance.  For a list of the classes see Net::HTTP.
+# - Net::HTTPRedirection:
 #
-# Correspondence <code>HTTP code => class</code> is stored in CODE_TO_OBJ
-# constant:
+#   - Net::HTTPMultipleChoices (300)
+#   - Net::HTTPMovedPermanently (301)
+#   - Net::HTTPFound (302)
+#   - Net::HTTPSeeOther (303)
+#   - Net::HTTPNotModified (304)
+#   - Net::HTTPUseProxy (305)
+#   - Net::HTTPTemporaryRedirect (307)
+#   - Net::HTTPPermanentRedirect (308)
 #
-#    Net::HTTPResponse::CODE_TO_OBJ['404'] #=> Net::HTTPNotFound
+# - Net::HTTPClientError:
+#
+#   - Net::HTTPBadRequest (400)
+#   - Net::HTTPUnauthorized (401)
+#   - Net::HTTPPaymentRequired (402)
+#   - Net::HTTPForbidden (403)
+#   - Net::HTTPNotFound (404)
+#   - Net::HTTPMethodNotAllowed (405)
+#   - Net::HTTPNotAcceptable (406)
+#   - Net::HTTPProxyAuthenticationRequired (407)
+#   - Net::HTTPRequestTimeOut (408)
+#   - Net::HTTPConflict (409)
+#   - Net::HTTPGone (410)
+#   - Net::HTTPLengthRequired (411)
+#   - Net::HTTPPreconditionFailed (412)
+#   - Net::HTTPRequestEntityTooLarge (413)
+#   - Net::HTTPRequestURITooLong (414)
+#   - Net::HTTPUnsupportedMediaType (415)
+#   - Net::HTTPRequestedRangeNotSatisfiable (416)
+#   - Net::HTTPExpectationFailed (417)
+#   - Net::HTTPMisdirectedRequest (421)
+#   - Net::HTTPUnprocessableEntity (422)
+#   - Net::HTTPLocked (423)
+#   - Net::HTTPFailedDependency (424)
+#   - Net::HTTPUpgradeRequired (426)
+#   - Net::HTTPPreconditionRequired (428)
+#   - Net::HTTPTooManyRequests (429)
+#   - Net::HTTPRequestHeaderFieldsTooLarge (431)
+#   - Net::HTTPUnavailableForLegalReasons (451)
+#
+# - Net::HTTPServerError:
+#
+#   - Net::HTTPInternalServerError (500)
+#   - Net::HTTPNotImplemented (501)
+#   - Net::HTTPBadGateway (502)
+#   - Net::HTTPServiceUnavailable (503)
+#   - Net::HTTPGatewayTimeOut (504)
+#   - Net::HTTPVersionNotSupported (505)
+#   - Net::HTTPVariantAlsoNegotiates (506)
+#   - Net::HTTPInsufficientStorage (507)
+#   - Net::HTTPLoopDetected (508)
+#   - Net::HTTPNotExtended (510)
+#   - Net::HTTPNetworkAuthenticationRequired (511)
+#
+# There is also the Net::HTTPBadResponse exception which is raised when
+# there is a protocol error.
 #
 class Net::HTTPResponse
   class << self
@@ -85,6 +201,7 @@ class Net::HTTPResponse
     @uri  = nil
     @decode_content = false
     @body_encoding = false
+    @ignore_eof = true
   end
 
   # The HTTP version supported by the server.
@@ -107,18 +224,41 @@ class Net::HTTPResponse
   # Accept-Encoding header from the user.
   attr_accessor :decode_content
 
-  # The encoding to use for the response body. If Encoding, use that encoding.
-  # If other true value, attempt to detect the appropriate encoding, and use
-  # that.
+  # Returns the value set by body_encoding=, or +false+ if none;
+  # see #body_encoding=.
   attr_reader :body_encoding
 
-  # Set the encoding to use for the response body.  If given a String, find
-  # the related Encoding.
+  # Sets the encoding that should be used when reading the body:
+  #
+  # - If the given value is an Encoding object, that encoding will be used.
+  # - Otherwise if the value is a string, the value of
+  #   {Encoding#find(value)}[rdoc-ref:Encoding.find]
+  #   will be used.
+  # - Otherwise an encoding will be deduced from the body itself.
+  #
+  # Examples:
+  #
+  #   http = Net::HTTP.new(hostname)
+  #   req = Net::HTTP::Get.new('/')
+  #
+  #   http.request(req) do |res|
+  #     p res.body.encoding # => #<Encoding:ASCII-8BIT>
+  #   end
+  #
+  #   http.request(req) do |res|
+  #     res.body_encoding = "UTF-8"
+  #     p res.body.encoding # => #<Encoding:UTF-8>
+  #   end
+  #
   def body_encoding=(value)
     value = Encoding.find(value) if value.is_a?(String)
     @body_encoding = value
   end
 
+  # Whether to ignore EOF when reading bodies with a specified Content-Length
+  # header.
+  attr_accessor :ignore_eof
+
   def inspect
     "#<#{self.class} #{@code} #{@message} readbody=#{@read}>"
   end
@@ -133,7 +273,7 @@ class Net::HTTPResponse
 
   def error!   #:nodoc:
     message = @code
-    message += ' ' + @message.dump if @message
+    message = "#{message} #{@message.dump}" if @message
     raise error_type().new(message, self)
   end
 
@@ -226,6 +366,7 @@ class Net::HTTPResponse
       @body = nil
     end
     @read = true
+    return if @body.nil?
 
     case enc = @body_encoding
     when Encoding, false, nil
@@ -241,26 +382,26 @@ class Net::HTTPResponse
     @body
   end
 
-  # Returns the full entity body.
+  # Returns the string response body;
+  # note that repeated calls for the unmodified body return a cached string:
   #
-  # Calling this method a second or subsequent time will return the
-  # string already read.
+  #   path = '/todos/1'
+  #   Net::HTTP.start(hostname) do |http|
+  #     res = http.get(path)
+  #     p res.body
+  #     p http.head(path).body # No body.
+  #   end
   #
-  #   http.request_get('/index.html') {|res|
-  #     puts res.body
-  #   }
+  # Output:
   #
-  #   http.request_get('/index.html') {|res|
-  #     p res.body.object_id   # 538149362
-  #     p res.body.object_id   # 538149362
-  #   }
+  #   "{\n  \"userId\": 1,\n  \"id\": 1,\n  \"title\": \"delectus aut autem\",\n  \"completed\": false\n}"
+  #   nil
   #
   def body
     read_body()
   end
 
-  # Because it may be necessary to modify the body, Eg, decompression
-  # this method facilitates that.
+  # Sets the body of the response to the given value.
   def body=(value)
     @body = value
   end
@@ -431,6 +572,9 @@ class Net::HTTPResponse
       ensure
         begin
           inflate_body_io.finish
+          if self['content-length']
+            self['content-length'] = inflate_body_io.bytes_inflated.to_s
+          end
         rescue => err
           # Ignore #finish's error if there is an exception from yield
           raise err if success
@@ -456,7 +600,7 @@ class Net::HTTPResponse
 
       clen = content_length()
       if clen
-        @socket.read clen, dest, true   # ignore EOF
+        @socket.read clen, dest, @ignore_eof
         return
       end
       clen = range_length()
@@ -496,7 +640,7 @@ class Net::HTTPResponse
   end
 
   def stream_check
-    raise IOError, 'attempt to read body out of block' if @socket.closed?
+    raise IOError, 'attempt to read body out of block' if @socket.nil? || @socket.closed?
   end
 
   def procdest(dest, block)
@@ -505,7 +649,7 @@ class Net::HTTPResponse
     if block
       Net::ReadAdapter.new(block)
     else
-      dest || ''
+      dest || +''
     end
   end
 
@@ -533,6 +677,14 @@ class Net::HTTPResponse
     end
 
     ##
+    # The number of bytes inflated, used to update the Content-Length of
+    # the response.
+
+    def bytes_inflated
+      @inflate.total_out
+    end
+
+    ##
     # Returns a Net::ReadAdapter that inflates each read chunk into +dest+.
     #
     # This allows a large response body to be inflated without storing the
diff --git a/lib/net/http/responses.rb b/lib/net/http/responses.rb
index 50352032df..6f6fb8d055 100644
--- a/lib/net/http/responses.rb
+++ b/lib/net/http/responses.rb
@@ -1,231 +1,1100 @@
 # frozen_string_literal: true
-# :stopdoc:
+#--
 # https://www.iana.org/assignments/http-status-codes/http-status-codes.xhtml
-class Net::HTTPUnknownResponse < Net::HTTPResponse
-  HAS_BODY = true
-  EXCEPTION_TYPE = Net::HTTPError
-end
-class Net::HTTPInformation < Net::HTTPResponse           # 1xx
-  HAS_BODY = false
-  EXCEPTION_TYPE = Net::HTTPError
-end
-class Net::HTTPSuccess < Net::HTTPResponse               # 2xx
-  HAS_BODY = true
-  EXCEPTION_TYPE = Net::HTTPError
-end
-class Net::HTTPRedirection < Net::HTTPResponse           # 3xx
-  HAS_BODY = true
-  EXCEPTION_TYPE = Net::HTTPRetriableError
-end
-class Net::HTTPClientError < Net::HTTPResponse           # 4xx
-  HAS_BODY = true
-  EXCEPTION_TYPE = Net::HTTPClientException   # for backward compatibility
-end
-class Net::HTTPServerError < Net::HTTPResponse           # 5xx
-  HAS_BODY = true
-  EXCEPTION_TYPE = Net::HTTPFatalError    # for backward compatibility
-end
 
-class Net::HTTPContinue < Net::HTTPInformation           # 100
-  HAS_BODY = false
-end
-class Net::HTTPSwitchProtocol < Net::HTTPInformation     # 101
-  HAS_BODY = false
-end
-class Net::HTTPProcessing < Net::HTTPInformation         # 102
-  HAS_BODY = false
-end
-class Net::HTTPEarlyHints < Net::HTTPInformation         # 103 - RFC 8297
-  HAS_BODY = false
-end
+module Net
 
-class Net::HTTPOK < Net::HTTPSuccess                            # 200
-  HAS_BODY = true
-end
-class Net::HTTPCreated < Net::HTTPSuccess                       # 201
-  HAS_BODY = true
-end
-class Net::HTTPAccepted < Net::HTTPSuccess                      # 202
-  HAS_BODY = true
-end
-class Net::HTTPNonAuthoritativeInformation < Net::HTTPSuccess   # 203
-  HAS_BODY = true
-end
-class Net::HTTPNoContent < Net::HTTPSuccess                     # 204
-  HAS_BODY = false
-end
-class Net::HTTPResetContent < Net::HTTPSuccess                  # 205
-  HAS_BODY = false
-end
-class Net::HTTPPartialContent < Net::HTTPSuccess                # 206
-  HAS_BODY = true
-end
-class Net::HTTPMultiStatus < Net::HTTPSuccess                   # 207 - RFC 4918
-  HAS_BODY = true
-end
-class Net::HTTPAlreadyReported < Net::HTTPSuccess               # 208 - RFC 5842
-  HAS_BODY = true
-end
-class Net::HTTPIMUsed < Net::HTTPSuccess                        # 226 - RFC 3229
-  HAS_BODY = true
-end
+  class HTTPUnknownResponse < HTTPResponse
+    HAS_BODY = true
+    EXCEPTION_TYPE = HTTPError                  #
+  end
 
-class Net::HTTPMultipleChoices < Net::HTTPRedirection    # 300
-  HAS_BODY = true
-end
-Net::HTTPMultipleChoice = Net::HTTPMultipleChoices
-class Net::HTTPMovedPermanently < Net::HTTPRedirection   # 301
-  HAS_BODY = true
-end
-class Net::HTTPFound < Net::HTTPRedirection              # 302
-  HAS_BODY = true
-end
-Net::HTTPMovedTemporarily = Net::HTTPFound
-class Net::HTTPSeeOther < Net::HTTPRedirection           # 303
-  HAS_BODY = true
-end
-class Net::HTTPNotModified < Net::HTTPRedirection        # 304
-  HAS_BODY = false
-end
-class Net::HTTPUseProxy < Net::HTTPRedirection           # 305
-  HAS_BODY = false
-end
-# 306 Switch Proxy - no longer unused
-class Net::HTTPTemporaryRedirect < Net::HTTPRedirection  # 307
-  HAS_BODY = true
-end
-class Net::HTTPPermanentRedirect < Net::HTTPRedirection  # 308
-  HAS_BODY = true
-end
+  # Parent class for informational (1xx) HTTP response classes.
+  #
+  # An informational response indicates that the request was received and understood.
+  #
+  # References:
+  #
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#status.1xx].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#1xx_informational_response].
+  #
+  class HTTPInformation < HTTPResponse
+    HAS_BODY = false
+    EXCEPTION_TYPE = HTTPError                  #
+  end
 
-class Net::HTTPBadRequest < Net::HTTPClientError                    # 400
-  HAS_BODY = true
-end
-class Net::HTTPUnauthorized < Net::HTTPClientError                  # 401
-  HAS_BODY = true
-end
-class Net::HTTPPaymentRequired < Net::HTTPClientError               # 402
-  HAS_BODY = true
-end
-class Net::HTTPForbidden < Net::HTTPClientError                     # 403
-  HAS_BODY = true
-end
-class Net::HTTPNotFound < Net::HTTPClientError                      # 404
-  HAS_BODY = true
-end
-class Net::HTTPMethodNotAllowed < Net::HTTPClientError              # 405
-  HAS_BODY = true
-end
-class Net::HTTPNotAcceptable < Net::HTTPClientError                 # 406
-  HAS_BODY = true
-end
-class Net::HTTPProxyAuthenticationRequired < Net::HTTPClientError   # 407
-  HAS_BODY = true
-end
-class Net::HTTPRequestTimeout < Net::HTTPClientError                # 408
-  HAS_BODY = true
-end
-Net::HTTPRequestTimeOut = Net::HTTPRequestTimeout
-class Net::HTTPConflict < Net::HTTPClientError                      # 409
-  HAS_BODY = true
-end
-class Net::HTTPGone < Net::HTTPClientError                          # 410
-  HAS_BODY = true
-end
-class Net::HTTPLengthRequired < Net::HTTPClientError                # 411
-  HAS_BODY = true
-end
-class Net::HTTPPreconditionFailed < Net::HTTPClientError            # 412
-  HAS_BODY = true
-end
-class Net::HTTPPayloadTooLarge < Net::HTTPClientError               # 413
-  HAS_BODY = true
-end
-Net::HTTPRequestEntityTooLarge = Net::HTTPPayloadTooLarge
-class Net::HTTPURITooLong < Net::HTTPClientError                    # 414
-  HAS_BODY = true
-end
-Net::HTTPRequestURITooLong = Net::HTTPURITooLong
-Net::HTTPRequestURITooLarge = Net::HTTPRequestURITooLong
-class Net::HTTPUnsupportedMediaType < Net::HTTPClientError          # 415
-  HAS_BODY = true
-end
-class Net::HTTPRangeNotSatisfiable < Net::HTTPClientError           # 416
-  HAS_BODY = true
-end
-Net::HTTPRequestedRangeNotSatisfiable = Net::HTTPRangeNotSatisfiable
-class Net::HTTPExpectationFailed < Net::HTTPClientError             # 417
-  HAS_BODY = true
-end
-# 418 I'm a teapot - RFC 2324; a joke RFC
-# 420 Enhance Your Calm - Twitter
-class Net::HTTPMisdirectedRequest < Net::HTTPClientError            # 421 - RFC 7540
-  HAS_BODY = true
-end
-class Net::HTTPUnprocessableEntity < Net::HTTPClientError           # 422 - RFC 4918
-  HAS_BODY = true
-end
-class Net::HTTPLocked < Net::HTTPClientError                        # 423 - RFC 4918
-  HAS_BODY = true
-end
-class Net::HTTPFailedDependency < Net::HTTPClientError              # 424 - RFC 4918
-  HAS_BODY = true
-end
-# 425 Unordered Collection - existed only in draft
-class Net::HTTPUpgradeRequired < Net::HTTPClientError               # 426 - RFC 2817
-  HAS_BODY = true
-end
-class Net::HTTPPreconditionRequired < Net::HTTPClientError          # 428 - RFC 6585
-  HAS_BODY = true
-end
-class Net::HTTPTooManyRequests < Net::HTTPClientError               # 429 - RFC 6585
-  HAS_BODY = true
-end
-class Net::HTTPRequestHeaderFieldsTooLarge < Net::HTTPClientError   # 431 - RFC 6585
-  HAS_BODY = true
-end
-class Net::HTTPUnavailableForLegalReasons < Net::HTTPClientError    # 451 - RFC 7725
-  HAS_BODY = true
-end
-# 444 No Response - Nginx
-# 449 Retry With - Microsoft
-# 450 Blocked by Windows Parental Controls - Microsoft
-# 499 Client Closed Request - Nginx
+  # Parent class for success (2xx) HTTP response classes.
+  #
+  # A success response indicates the action requested by the client
+  # was received, understood, and accepted.
+  #
+  # References:
+  #
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#status.2xx].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#2xx_success].
+  #
+  class HTTPSuccess < HTTPResponse
+    HAS_BODY = true
+    EXCEPTION_TYPE = HTTPError                  #
+  end
+
+  # Parent class for redirection (3xx) HTTP response classes.
+  #
+  # A redirection response indicates the client must take additional action
+  # to complete the request.
+  #
+  # References:
+  #
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#status.3xx].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#3xx_redirection].
+  #
+  class HTTPRedirection < HTTPResponse
+    HAS_BODY = true
+    EXCEPTION_TYPE = HTTPRetriableError         #
+  end
+
+  # Parent class for client error (4xx) HTTP response classes.
+  #
+  # A client error response indicates that the client may have caused an error.
+  #
+  # References:
+  #
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#status.4xx].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#4xx_client_errors].
+  #
+  class HTTPClientError < HTTPResponse
+    HAS_BODY = true
+    EXCEPTION_TYPE = HTTPClientException        #
+  end
+
+  # Parent class for server error (5xx) HTTP response classes.
+  #
+  # A server error response indicates that the server failed to fulfill a request.
+  #
+  # References:
+  #
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#status.5xx].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#5xx_server_errors].
+  #
+  class HTTPServerError < HTTPResponse
+    HAS_BODY = true
+    EXCEPTION_TYPE = HTTPFatalError             #
+  end
+
+  # Response class for +Continue+ responses (status code 100).
+  #
+  # A +Continue+ response indicates that the server has received the request headers.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/100].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-100-continue].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#100].
+  #
+  class HTTPContinue < HTTPInformation
+    HAS_BODY = false
+  end
+
+  # Response class for <tt>Switching Protocol</tt> responses (status code 101).
+  #
+  # The <tt>Switching Protocol<tt> response indicates that the server has received
+  # a request to switch protocols, and has agreed to do so.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/101].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-101-switching-protocols].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#101].
+  #
+  class HTTPSwitchProtocol < HTTPInformation
+    HAS_BODY = false
+  end
+
+  # Response class for +Processing+ responses (status code 102).
+  #
+  # The +Processing+ response indicates that the server has received
+  # and is processing the request, but no response is available yet.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {RFC 2518}[https://www.rfc-editor.org/rfc/rfc2518#section-10.1].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#102].
+  #
+  class HTTPProcessing < HTTPInformation
+    HAS_BODY = false
+  end
+
+  # Response class for <tt>Early Hints</tt> responses (status code 103).
+  #
+  # The <tt>Early Hints</tt> indicates that the server has received
+  # and is processing the request, and contains certain headers;
+  # the final response is not available yet.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/103].
+  # - {RFC 8297}[https://www.rfc-editor.org/rfc/rfc8297.html#section-2].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#103].
+  #
+  class HTTPEarlyHints < HTTPInformation
+    HAS_BODY = false
+  end
+
+  # Response class for +OK+ responses (status code 200).
+  #
+  # The +OK+ response indicates that the server has received
+  # a request and has responded successfully.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/200].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-200-ok].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#200].
+  #
+  class HTTPOK < HTTPSuccess
+    HAS_BODY = true
+  end
+
+  # Response class for +Created+ responses (status code 201).
+  #
+  # The +Created+ response indicates that the server has received
+  # and has fulfilled a request to create a new resource.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/201].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-201-created].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#201].
+  #
+  class HTTPCreated < HTTPSuccess
+    HAS_BODY = true
+  end
+
+  # Response class for +Accepted+ responses (status code 202).
+  #
+  # The +Accepted+ response indicates that the server has received
+  # and is processing a request, but the processing has not yet been completed.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/202].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-202-accepted].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#202].
+  #
+  class HTTPAccepted < HTTPSuccess
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Non-Authoritative Information</tt> responses (status code 203).
+  #
+  # The <tt>Non-Authoritative Information</tt> response indicates that the server
+  # is a transforming proxy (such as a Web accelerator)
+  # that received a 200 OK response from its origin,
+  # and is returning a modified version of the origin's response.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/203].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-203-non-authoritative-infor].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#203].
+  #
+  class HTTPNonAuthoritativeInformation < HTTPSuccess
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>No Content</tt> responses (status code 204).
+  #
+  # The <tt>No Content</tt> response indicates that the server
+  # successfully processed the request, and is not returning any content.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/204].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-204-no-content].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#204].
+  #
+  class HTTPNoContent < HTTPSuccess
+    HAS_BODY = false
+  end
+
+  # Response class for <tt>Reset Content</tt> responses (status code 205).
+  #
+  # The <tt>Reset Content</tt> response indicates that the server
+  # successfully processed the request,
+  # asks that the client reset its document view, and is not returning any content.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/205].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-205-reset-content].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#205].
+  #
+  class HTTPResetContent < HTTPSuccess
+    HAS_BODY = false
+  end
+
+  # Response class for <tt>Partial Content</tt> responses (status code 206).
+  #
+  # The <tt>Partial Content</tt> response indicates that the server is delivering
+  # only part of the resource (byte serving)
+  # due to a Range header in the request.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/206].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-206-partial-content].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#206].
+  #
+  class HTTPPartialContent < HTTPSuccess
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Multi-Status (WebDAV)</tt> responses (status code 207).
+  #
+  # The <tt>Multi-Status (WebDAV)</tt> response indicates that the server
+  # has received the request,
+  # and that the message body can contain a number of separate response codes.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {RFC 4818}[https://www.rfc-editor.org/rfc/rfc4918#section-11.1].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#207].
+  #
+  class HTTPMultiStatus < HTTPSuccess
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Already Reported (WebDAV)</tt> responses (status code 208).
+  #
+  # The <tt>Already Reported (WebDAV)</tt> response indicates that the server
+  # has received the request,
+  # and that the members of a DAV binding have already been enumerated
+  # in a preceding part of the (multi-status) response,
+  # and are not being included again.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {RFC 5842}[https://www.rfc-editor.org/rfc/rfc5842.html#section-7.1].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#208].
+  #
+  class HTTPAlreadyReported < HTTPSuccess
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>IM Used</tt> responses (status code 226).
+  #
+  # The <tt>IM Used</tt> response indicates that the server has fulfilled a request
+  # for the resource, and the response is a representation of the result
+  # of one or more instance-manipulations applied to the current instance.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {RFC 3229}[https://www.rfc-editor.org/rfc/rfc3229.html#section-10.4.1].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#226].
+  #
+  class HTTPIMUsed < HTTPSuccess
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Multiple Choices</tt> responses (status code 300).
+  #
+  # The <tt>Multiple Choices</tt> response indicates that the server
+  # offers multiple options for the resource from which the client may choose.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/300].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-300-multiple-choices].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#300].
+  #
+  class HTTPMultipleChoices < HTTPRedirection
+    HAS_BODY = true
+  end
+  HTTPMultipleChoice = HTTPMultipleChoices
+
+  # Response class for <tt>Moved Permanently</tt> responses (status code 301).
+  #
+  # The <tt>Moved Permanently</tt> response indicates that links or records
+  # returning this response should be updated to use the given URL.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/301].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-301-moved-permanently].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#301].
+  #
+  class HTTPMovedPermanently < HTTPRedirection
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Found</tt> responses (status code 302).
+  #
+  # The <tt>Found</tt> response indicates that the client
+  # should look at (browse to) another URL.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/302].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-302-found].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#302].
+  #
+  class HTTPFound < HTTPRedirection
+    HAS_BODY = true
+  end
+  HTTPMovedTemporarily = HTTPFound
+
+  # Response class for <tt>See Other</tt> responses (status code 303).
+  #
+  # The response to the request can be found under another URI using the GET method.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/303].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-303-see-other].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#303].
+  #
+  class HTTPSeeOther < HTTPRedirection
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Not Modified</tt> responses (status code 304).
+  #
+  # Indicates that the resource has not been modified since the version
+  # specified by the request headers.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/304].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-304-not-modified].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#304].
+  #
+  class HTTPNotModified < HTTPRedirection
+    HAS_BODY = false
+  end
+
+  # Response class for <tt>Use Proxy</tt> responses (status code 305).
+  #
+  # The requested resource is available only through a proxy,
+  # whose address is provided in the response.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-305-use-proxy].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#305].
+  #
+  class HTTPUseProxy < HTTPRedirection
+    HAS_BODY = false
+  end
+
+  # Response class for <tt>Temporary Redirect</tt> responses (status code 307).
+  #
+  # The request should be repeated with another URI;
+  # however, future requests should still use the original URI.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/307].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-307-temporary-redirect].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#307].
+  #
+  class HTTPTemporaryRedirect < HTTPRedirection
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Permanent Redirect</tt> responses (status code 308).
+  #
+  # This and all future requests should be directed to the given URI.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/308].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-308-permanent-redirect].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#308].
+  #
+  class HTTPPermanentRedirect < HTTPRedirection
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Bad Request</tt> responses (status code 400).
+  #
+  # The server cannot or will not process the request due to an apparent client error.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/400].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-400-bad-request].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#400].
+  #
+  class HTTPBadRequest < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Unauthorized</tt> responses (status code 401).
+  #
+  # Authentication is required, but either was not provided or failed.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/401].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-401-unauthorized].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#401].
+  #
+  class HTTPUnauthorized < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Payment Required</tt> responses (status code 402).
+  #
+  # Reserved for future use.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/402].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-402-payment-required].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#402].
+  #
+  class HTTPPaymentRequired < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Forbidden</tt> responses (status code 403).
+  #
+  # The request contained valid data and was understood by the server,
+  # but the server is refusing action.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/403].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-403-forbidden].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#403].
+  #
+  class HTTPForbidden < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Not Found</tt> responses (status code 404).
+  #
+  # The requested resource could not be found but may be available in the future.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/404].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-404-not-found].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#404].
+  #
+  class HTTPNotFound < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Method Not Allowed</tt> responses (status code 405).
+  #
+  # The request method is not supported for the requested resource.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/405].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-405-method-not-allowed].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#405].
+  #
+  class HTTPMethodNotAllowed < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Not Acceptable</tt> responses (status code 406).
+  #
+  # The requested resource is capable of generating only content
+  # that not acceptable according to the Accept headers sent in the request.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/406].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-406-not-acceptable].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#406].
+  #
+  class HTTPNotAcceptable < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Proxy Authentication Required</tt> responses (status code 407).
+  #
+  # The client must first authenticate itself with the proxy.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/407].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-407-proxy-authentication-re].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#407].
+  #
+  class HTTPProxyAuthenticationRequired < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Request Timeout</tt> responses (status code 408).
+  #
+  # The server timed out waiting for the request.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/408].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-408-request-timeout].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#408].
+  #
+  class HTTPRequestTimeout < HTTPClientError
+    HAS_BODY = true
+  end
+  HTTPRequestTimeOut = HTTPRequestTimeout
+
+  # Response class for <tt>Conflict</tt> responses (status code 409).
+  #
+  # The request could not be processed because of conflict in the current state of the resource.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/409].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-409-conflict].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#409].
+  #
+  class HTTPConflict < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Gone</tt> responses (status code 410).
+  #
+  # The resource requested was previously in use but is no longer available
+  # and will not be available again.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/410].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-410-gone].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#410].
+  #
+  class HTTPGone < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Length Required</tt> responses (status code 411).
+  #
+  # The request did not specify the length of its content,
+  # which is required by the requested resource.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/411].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-411-length-required].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#411].
+  #
+  class HTTPLengthRequired < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Precondition Failed</tt> responses (status code 412).
+  #
+  # The server does not meet one of the preconditions
+  # specified in the request headers.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/412].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-412-precondition-failed].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#412].
+  #
+  class HTTPPreconditionFailed < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Payload Too Large</tt> responses (status code 413).
+  #
+  # The request is larger than the server is willing or able to process.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/413].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-413-content-too-large].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#413].
+  #
+  class HTTPPayloadTooLarge < HTTPClientError
+    HAS_BODY = true
+  end
+  HTTPRequestEntityTooLarge = HTTPPayloadTooLarge
+
+  # Response class for <tt>URI Too Long</tt> responses (status code 414).
+  #
+  # The URI provided was too long for the server to process.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/414].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-414-uri-too-long].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#414].
+  #
+  class HTTPURITooLong < HTTPClientError
+    HAS_BODY = true
+  end
+  HTTPRequestURITooLong = HTTPURITooLong
+  HTTPRequestURITooLarge = HTTPRequestURITooLong
+
+  # Response class for <tt>Unsupported Media Type</tt> responses (status code 415).
+  #
+  # The request entity has a media type which the server or resource does not support.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/415].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-415-unsupported-media-type].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#415].
+  #
+  class HTTPUnsupportedMediaType < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Range Not Satisfiable</tt> responses (status code 416).
+  #
+  # The request entity has a media type which the server or resource does not support.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/416].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-416-range-not-satisfiable].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#416].
+  #
+  class HTTPRangeNotSatisfiable < HTTPClientError
+    HAS_BODY = true
+  end
+  HTTPRequestedRangeNotSatisfiable = HTTPRangeNotSatisfiable
+
+  # Response class for <tt>Expectation Failed</tt> responses (status code 417).
+  #
+  # The server cannot meet the requirements of the Expect request-header field.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/417].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-417-expectation-failed].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#417].
+  #
+  class HTTPExpectationFailed < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # 418 I'm a teapot - RFC 2324; a joke RFC
+  # See https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#418.
+
+  # 420 Enhance Your Calm - Twitter
+
+  # Response class for <tt>Misdirected Request</tt> responses (status code 421).
+  #
+  # The request was directed at a server that is not able to produce a response.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-421-misdirected-request].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#421].
+  #
+  class HTTPMisdirectedRequest < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Unprocessable Entity</tt> responses (status code 422).
+  #
+  # The request was well-formed but had semantic errors.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/422].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-422-unprocessable-content].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#422].
+  #
+  class HTTPUnprocessableEntity < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Locked (WebDAV)</tt> responses (status code 423).
+  #
+  # The requested resource is locked.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {RFC 4918}[https://www.rfc-editor.org/rfc/rfc4918#section-11.3].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#423].
+  #
+  class HTTPLocked < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Failed Dependency (WebDAV)</tt> responses (status code 424).
+  #
+  # The request failed because it depended on another request and that request failed.
+  # See {424 Failed Dependency (WebDAV)}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#424].
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {RFC 4918}[https://www.rfc-editor.org/rfc/rfc4918#section-11.4].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#424].
+  #
+  class HTTPFailedDependency < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # 425 Too Early
+  # https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#425.
+
+  # Response class for <tt>Upgrade Required</tt> responses (status code 426).
+  #
+  # The client should switch to the protocol given in the Upgrade header field.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/426].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-426-upgrade-required].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#426].
+  #
+  class HTTPUpgradeRequired < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Precondition Required</tt> responses (status code 428).
+  #
+  # The origin server requires the request to be conditional.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/428].
+  # - {RFC 6585}[https://www.rfc-editor.org/rfc/rfc6585#section-3].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#428].
+  #
+  class HTTPPreconditionRequired < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Too Many Requests</tt> responses (status code 429).
+  #
+  # The user has sent too many requests in a given amount of time.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/429].
+  # - {RFC 6585}[https://www.rfc-editor.org/rfc/rfc6585#section-4].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#429].
+  #
+  class HTTPTooManyRequests < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Request Header Fields Too Large</tt> responses (status code 431).
+  #
+  # An individual header field is too large,
+  # or all the header fields collectively, are too large.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/431].
+  # - {RFC 6585}[https://www.rfc-editor.org/rfc/rfc6585#section-5].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#431].
+  #
+  class HTTPRequestHeaderFieldsTooLarge < HTTPClientError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Unavailable For Legal Reasons</tt> responses (status code 451).
+  #
+  # A server operator has received a legal demand to deny access to a resource or to a set of resources
+  # that includes the requested resource.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/451].
+  # - {RFC 7725}[https://www.rfc-editor.org/rfc/rfc7725.html#section-3].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#451].
+  #
+  class HTTPUnavailableForLegalReasons < HTTPClientError
+    HAS_BODY = true
+  end
+  # 444 No Response - Nginx
+  # 449 Retry With - Microsoft
+  # 450 Blocked by Windows Parental Controls - Microsoft
+  # 499 Client Closed Request - Nginx
+
+  # Response class for <tt>Internal Server Error</tt> responses (status code 500).
+  #
+  # An unexpected condition was encountered and no more specific message is suitable.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/500].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-500-internal-server-error].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#500].
+  #
+  class HTTPInternalServerError < HTTPServerError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Not Implemented</tt> responses (status code 501).
+  #
+  # The server either does not recognize the request method,
+  # or it lacks the ability to fulfil the request.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/501].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-501-not-implemented].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#501].
+  #
+  class HTTPNotImplemented < HTTPServerError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Bad Gateway</tt> responses (status code 502).
+  #
+  # The server was acting as a gateway or proxy
+  # and received an invalid response from the upstream server.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/502].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-502-bad-gateway].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#502].
+  #
+  class HTTPBadGateway < HTTPServerError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Service Unavailable</tt> responses (status code 503).
+  #
+  # The server cannot handle the request
+  # (because it is overloaded or down for maintenance).
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/503].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-503-service-unavailable].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#503].
+  #
+  class HTTPServiceUnavailable < HTTPServerError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Gateway Timeout</tt> responses (status code 504).
+  #
+  # The server was acting as a gateway or proxy
+  # and did not receive a timely response from the upstream server.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/504].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-504-gateway-timeout].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#504].
+  #
+  class HTTPGatewayTimeout < HTTPServerError
+    HAS_BODY = true
+  end
+  HTTPGatewayTimeOut = HTTPGatewayTimeout
+
+  # Response class for <tt>HTTP Version Not Supported</tt> responses (status code 505).
+  #
+  # The server does not support the HTTP version used in the request.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/505].
+  # - {RFC 9110}[https://www.rfc-editor.org/rfc/rfc9110.html#name-505-http-version-not-suppor].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#505].
+  #
+  class HTTPVersionNotSupported < HTTPServerError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Variant Also Negotiates</tt> responses (status code 506).
+  #
+  # Transparent content negotiation for the request results in a circular reference.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/506].
+  # - {RFC 2295}[https://www.rfc-editor.org/rfc/rfc2295#section-8.1].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#506].
+  #
+  class HTTPVariantAlsoNegotiates < HTTPServerError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Insufficient Storage (WebDAV)</tt> responses (status code 507).
+  #
+  # The server is unable to store the representation needed to complete the request.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/507].
+  # - {RFC 4918}[https://www.rfc-editor.org/rfc/rfc4918#section-11.5].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#507].
+  #
+  class HTTPInsufficientStorage < HTTPServerError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Loop Detected (WebDAV)</tt> responses (status code 508).
+  #
+  # The server detected an infinite loop while processing the request.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/508].
+  # - {RFC 5942}[https://www.rfc-editor.org/rfc/rfc5842.html#section-7.2].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#508].
+  #
+  class HTTPLoopDetected < HTTPServerError
+    HAS_BODY = true
+  end
+  # 509 Bandwidth Limit Exceeded - Apache bw/limited extension
+
+  # Response class for <tt>Not Extended</tt> responses (status code 510).
+  #
+  # Further extensions to the request are required for the server to fulfill it.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/510].
+  # - {RFC 2774}[https://www.rfc-editor.org/rfc/rfc2774.html#section-7].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#510].
+  #
+  class HTTPNotExtended < HTTPServerError
+    HAS_BODY = true
+  end
+
+  # Response class for <tt>Network Authentication Required</tt> responses (status code 511).
+  #
+  # The client needs to authenticate to gain network access.
+  #
+  # :include: doc/net-http/included_getters.rdoc
+  #
+  # References:
+  #
+  # - {Mozilla}[https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/511].
+  # - {RFC 6585}[https://www.rfc-editor.org/rfc/rfc6585#section-6].
+  # - {Wikipedia}[https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#511].
+  #
+  class HTTPNetworkAuthenticationRequired < HTTPServerError
+    HAS_BODY = true
+  end
 
-class Net::HTTPInternalServerError < Net::HTTPServerError           # 500
-  HAS_BODY = true
-end
-class Net::HTTPNotImplemented < Net::HTTPServerError                # 501
-  HAS_BODY = true
-end
-class Net::HTTPBadGateway < Net::HTTPServerError                    # 502
-  HAS_BODY = true
-end
-class Net::HTTPServiceUnavailable < Net::HTTPServerError            # 503
-  HAS_BODY = true
-end
-class Net::HTTPGatewayTimeout < Net::HTTPServerError                # 504
-  HAS_BODY = true
-end
-Net::HTTPGatewayTimeOut = Net::HTTPGatewayTimeout
-class Net::HTTPVersionNotSupported < Net::HTTPServerError           # 505
-  HAS_BODY = true
-end
-class Net::HTTPVariantAlsoNegotiates < Net::HTTPServerError         # 506
-  HAS_BODY = true
-end
-class Net::HTTPInsufficientStorage < Net::HTTPServerError           # 507 - RFC 4918
-  HAS_BODY = true
-end
-class Net::HTTPLoopDetected < Net::HTTPServerError                  # 508 - RFC 5842
-  HAS_BODY = true
-end
-# 509 Bandwidth Limit Exceeded - Apache bw/limited extension
-class Net::HTTPNotExtended < Net::HTTPServerError                   # 510 - RFC 2774
-  HAS_BODY = true
-end
-class Net::HTTPNetworkAuthenticationRequired < Net::HTTPServerError # 511 - RFC 6585
-  HAS_BODY = true
 end
 
 class Net::HTTPResponse
@@ -303,5 +1172,3 @@ class Net::HTTPResponse
     '511' => Net::HTTPNetworkAuthenticationRequired,
   }
 end
-
-# :startdoc:
diff --git a/lib/net/http/status.rb b/lib/net/http/status.rb
index 8db3f7d9e3..e70b47d9fb 100644
--- a/lib/net/http/status.rb
+++ b/lib/net/http/status.rb
@@ -4,7 +4,7 @@ require_relative '../http'
 
 if $0 == __FILE__
   require 'open-uri'
-  IO.foreach(__FILE__) do |line|
+  File.foreach(__FILE__) do |line|
     puts line
     break if line.start_with?('end')
   end
@@ -16,7 +16,7 @@ if $0 == __FILE__
     next if ['(Unused)', 'Unassigned', 'Description'].include?(mes)
     puts "  #{code} => '#{mes}',"
   end
-  puts "}"
+  puts "} # :nodoc:"
 end
 
 Net::HTTP::STATUS_CODES = {
@@ -55,15 +55,16 @@ Net::HTTP::STATUS_CODES = {
   410 => 'Gone',
   411 => 'Length Required',
   412 => 'Precondition Failed',
-  413 => 'Payload Too Large',
+  413 => 'Content Too Large',
   414 => 'URI Too Long',
   415 => 'Unsupported Media Type',
   416 => 'Range Not Satisfiable',
   417 => 'Expectation Failed',
   421 => 'Misdirected Request',
-  422 => 'Unprocessable Entity',
+  422 => 'Unprocessable Content',
   423 => 'Locked',
   424 => 'Failed Dependency',
+  425 => 'Too Early',
   426 => 'Upgrade Required',
   428 => 'Precondition Required',
   429 => 'Too Many Requests',
@@ -78,6 +79,6 @@ Net::HTTP::STATUS_CODES = {
   506 => 'Variant Also Negotiates',
   507 => 'Insufficient Storage',
   508 => 'Loop Detected',
-  510 => 'Not Extended',
+  510 => 'Not Extended (OBSOLETED)',
   511 => 'Network Authentication Required',
-}
+} # :nodoc:
diff --git a/lib/net/https.rb b/lib/net/https.rb
index d46721c82a..0f23e1fb13 100644
--- a/lib/net/https.rb
+++ b/lib/net/https.rb
@@ -1,4 +1,4 @@
-# frozen_string_literal: false
+# frozen_string_literal: true
 =begin
 
 = net/https -- SSL/TLS enhancement for Net::HTTP.
diff --git a/lib/net/protocol.rb b/lib/net/protocol.rb
index 822bc00574..ea0752a971 100644
--- a/lib/net/protocol.rb
+++ b/lib/net/protocol.rb
@@ -26,7 +26,7 @@ require 'io/wait'
 module Net # :nodoc:
 
   class Protocol   #:nodoc: internal use only
-    VERSION = "0.1.3"
+    VERSION = "0.2.1"
 
     private
     def Protocol.protocol_param(name, val)
@@ -120,6 +120,8 @@ module Net # :nodoc:
       @continue_timeout = continue_timeout
       @debug_output = debug_output
       @rbuf = ''.b
+      @rbuf_empty = true
+      @rbuf_offset = 0
     end
 
     attr_reader :io
@@ -154,14 +156,15 @@ module Net # :nodoc:
       LOG "reading #{len} bytes..."
       read_bytes = 0
       begin
-        while read_bytes + @rbuf.size < len
-          s = rbuf_consume(@rbuf.size)
-          read_bytes += s.size
-          dest << s
+        while read_bytes + rbuf_size < len
+          if s = rbuf_consume_all
+            read_bytes += s.bytesize
+            dest << s
+          end
           rbuf_fill
         end
         s = rbuf_consume(len - read_bytes)
-        read_bytes += s.size
+        read_bytes += s.bytesize
         dest << s
       rescue EOFError
         raise unless ignore_eof
@@ -175,9 +178,10 @@ module Net # :nodoc:
       read_bytes = 0
       begin
         while true
-          s = rbuf_consume(@rbuf.size)
-          read_bytes += s.size
-          dest << s
+          if s = rbuf_consume_all
+            read_bytes += s.bytesize
+            dest << s
+          end
           rbuf_fill
         end
       rescue EOFError
@@ -188,14 +192,16 @@ module Net # :nodoc:
     end
 
     def readuntil(terminator, ignore_eof = false)
+      offset = @rbuf_offset
       begin
-        until idx = @rbuf.index(terminator)
+        until idx = @rbuf.index(terminator, offset)
+          offset = @rbuf.bytesize
           rbuf_fill
         end
-        return rbuf_consume(idx + terminator.size)
+        return rbuf_consume(idx + terminator.bytesize - @rbuf_offset)
       rescue EOFError
         raise unless ignore_eof
-        return rbuf_consume(@rbuf.size)
+        return rbuf_consume
       end
     end
 
@@ -208,12 +214,16 @@ module Net # :nodoc:
     BUFSIZE = 1024 * 16
 
     def rbuf_fill
-      tmp = @rbuf.empty? ? @rbuf : nil
+      tmp = @rbuf_empty ? @rbuf : nil
       case rv = @io.read_nonblock(BUFSIZE, tmp, exception: false)
       when String
-        return if rv.equal?(tmp)
-        @rbuf << rv
-        rv.clear
+        @rbuf_empty = false
+        if rv.equal?(tmp)
+          @rbuf_offset = 0
+        else
+          @rbuf << rv
+          rv.clear
+        end
         return
       when :wait_readable
         (io = @io.to_io).wait_readable(@read_timeout) or raise Net::ReadTimeout.new(io)
@@ -228,13 +238,40 @@ module Net # :nodoc:
       end while true
     end
 
-    def rbuf_consume(len)
-      if len == @rbuf.size
+    def rbuf_flush
+      if @rbuf_empty
+        @rbuf.clear
+        @rbuf_offset = 0
+      end
+      nil
+    end
+
+    def rbuf_size
+      @rbuf.bytesize - @rbuf_offset
+    end
+
+    def rbuf_consume_all
+      rbuf_consume if rbuf_size > 0
+    end
+
+    def rbuf_consume(len = nil)
+      if @rbuf_offset == 0 && (len.nil? || len == @rbuf.bytesize)
         s = @rbuf
         @rbuf = ''.b
+        @rbuf_offset = 0
+        @rbuf_empty = true
+      elsif len.nil?
+        s = @rbuf.byteslice(@rbuf_offset..-1)
+        @rbuf = ''.b
+        @rbuf_offset = 0
+        @rbuf_empty = true
       else
-        s = @rbuf.slice!(0, len)
+        s = @rbuf.byteslice(@rbuf_offset, len)
+        @rbuf_offset += len
+        @rbuf_empty = @rbuf_offset == @rbuf.bytesize
+        rbuf_flush
       end
+
       @debug_output << %Q[-> #{s.dump}\n] if @debug_output
       s
     end
diff --git a/lib/open-uri.gemspec b/lib/open-uri.gemspec
index 12f10ef316..cad63e4d80 100644
--- a/lib/open-uri.gemspec
+++ b/lib/open-uri.gemspec
@@ -1,6 +1,6 @@
 Gem::Specification.new do |spec|
   spec.name          = "open-uri"
-  spec.version       = "0.2.0"
+  spec.version       = "0.3.0"
   spec.authors       = ["Tanaka Akira"]
   spec.email         = ["akr@fsij.org"]
 
@@ -14,7 +14,7 @@ Gem::Specification.new do |spec|
   spec.metadata["source_code_uri"] = spec.homepage
 
   spec.files         = Dir.chdir(File.expand_path('..', __FILE__)) do
-    `git ls-files -z`.split("\x0").reject { |f| f.match(%r{^(test|spec|features)/}) }
+    `git ls-files -z`.split("\x0").reject { |f| f.match(%r{\A((bin|test|spec|features)/|\.git|[Rr]ake|Gemfile)|\.gemspec\z}) }
   end
   spec.executables   = []
   spec.require_paths = ["lib"]
diff --git a/lib/open-uri.rb b/lib/open-uri.rb
index e33e57a7f6..93e8cfcdb7 100644
--- a/lib/open-uri.rb
+++ b/lib/open-uri.rb
@@ -9,7 +9,7 @@ module URI
   # If the first argument responds to the 'open' method, 'open' is called on
   # it with the rest of the arguments.
   #
-  # If the first argument is a string that begins with <code>(protocol)://<code>, it is parsed by
+  # If the first argument is a string that begins with <code>(protocol)://</code>, it is parsed by
   # URI.parse.  If the parsed object responds to the 'open' method,
   # 'open' is called on it with the rest of the arguments.
   #
@@ -99,6 +99,8 @@ module OpenURI
     :open_timeout => true,
     :ssl_ca_cert => nil,
     :ssl_verify_mode => nil,
+    :ssl_min_version => nil,
+    :ssl_max_version => nil,
     :ftp_active_mode => false,
     :redirect => true,
     :encoding => nil,
@@ -298,6 +300,8 @@ module OpenURI
       require 'net/https'
       http.use_ssl = true
       http.verify_mode = options[:ssl_verify_mode] || OpenSSL::SSL::VERIFY_PEER
+      http.min_version = options[:ssl_min_version]
+      http.max_version = options[:ssl_max_version]
       store = OpenSSL::X509::Store.new
       if options[:ssl_ca_cert]
         Array(options[:ssl_ca_cert]).each do |cert|
@@ -353,7 +357,8 @@ module OpenURI
     when Net::HTTPMovedPermanently, # 301
          Net::HTTPFound, # 302
          Net::HTTPSeeOther, # 303
-         Net::HTTPTemporaryRedirect # 307
+         Net::HTTPTemporaryRedirect, # 307
+         Net::HTTPPermanentRedirect # 308
       begin
         loc_uri = URI.parse(resp['location'])
       rescue URI::InvalidURIError
@@ -410,6 +415,13 @@ module OpenURI
     end
   end
 
+  # :stopdoc:
+  RE_LWS = /[\r\n\t ]+/n
+  RE_TOKEN = %r{[^\x00- ()<>@,;:\\"/\[\]?={}\x7f]+}n
+  RE_QUOTED_STRING = %r{"(?:[\r\n\t !#-\[\]-~\x80-\xff]|\\[\x00-\x7f])*"}n
+  RE_PARAMETERS = %r{(?:;#{RE_LWS}?#{RE_TOKEN}#{RE_LWS}?=#{RE_LWS}?(?:#{RE_TOKEN}|#{RE_QUOTED_STRING})#{RE_LWS}?)*}n
+  # :startdoc:
+
   # Mixin for holding meta-information.
   module Meta
     def Meta.init(obj, src=nil) # :nodoc:
@@ -487,13 +499,6 @@ module OpenURI
       end
     end
 
-    # :stopdoc:
-    RE_LWS = /[\r\n\t ]+/n
-    RE_TOKEN = %r{[^\x00- ()<>@,;:\\"/\[\]?={}\x7f]+}n
-    RE_QUOTED_STRING = %r{"(?:[\r\n\t !#-\[\]-~\x80-\xff]|\\[\x00-\x7f])*"}n
-    RE_PARAMETERS = %r{(?:;#{RE_LWS}?#{RE_TOKEN}#{RE_LWS}?=#{RE_LWS}?(?:#{RE_TOKEN}|#{RE_QUOTED_STRING})#{RE_LWS}?)*}n
-    # :startdoc:
-
     def content_type_parse # :nodoc:
       vs = @metas['content-type']
       # The last (?:;#{RE_LWS}?)? matches extra ";" which violates RFC2045.
@@ -698,6 +703,20 @@ module OpenURI
     #
     #  :ssl_verify_mode is used to specify openssl verify mode.
     #
+    # [:ssl_min_version]
+    #  Synopsis:
+    #    :ssl_min_version=>:TLS1_2
+    #
+    #  :ssl_min_version option specifies the minimum allowed SSL/TLS protocol
+    #  version.  See also OpenSSL::SSL::SSLContext#min_version=.
+    #
+    # [:ssl_max_version]
+    #  Synopsis:
+    #    :ssl_max_version=>:TLS1_2
+    #
+    #  :ssl_max_version option specifies the maximum allowed SSL/TLS protocol
+    #  version.  See also OpenSSL::SSL::SSLContext#max_version=.
+    #
     # [:ftp_active_mode]
     #  Synopsis:
     #    :ftp_active_mode=>bool
diff --git a/lib/open3/version.rb b/lib/open3/version.rb
index 5a8e84b4ae..b6b6ee2c9c 100644
--- a/lib/open3/version.rb
+++ b/lib/open3/version.rb
@@ -1,3 +1,3 @@
 module Open3
-  VERSION = "0.1.1"
+  VERSION = "0.1.2"
 end
diff --git a/lib/optparse.rb b/lib/optparse.rb
index ec37bde3bd..53a4387bd8 100644
--- a/lib/optparse.rb
+++ b/lib/optparse.rb
@@ -425,7 +425,7 @@
 # If you have any questions, file a ticket at http://bugs.ruby-lang.org.
 #
 class OptionParser
-  OptionParser::Version = "0.2.0"
+  OptionParser::Version = "0.3.1"
 
   # :stopdoc:
   NoArgument = [NO_ARGUMENT = :NONE, nil].freeze
@@ -765,15 +765,15 @@ class OptionParser
     end
 
     #
-    # Switch that takes an argument, which does not begin with '-'.
+    # Switch that takes an argument, which does not begin with '-' or is '-'.
     #
     class PlacedArgument < self
 
       #
-      # Returns nil if argument is not present or begins with '-'.
+      # Returns nil if argument is not present or begins with '-' and is not '-'.
       #
       def parse(arg, argv, &error)
-        if !(val = arg) and (argv.empty? or /\A-/ =~ (val = argv[0]))
+        if !(val = arg) and (argv.empty? or /\A-./ =~ (val = argv[0]))
           return nil, block, nil
         end
         opt = (val = parse_arg(val, &error))[1]
@@ -1148,6 +1148,7 @@ XXX
     @summary_indent = indent
     @default_argv = ARGV
     @require_exact = false
+    @raise_unknown = true
     add_officious
     yield self if block_given?
   end
@@ -1225,6 +1226,9 @@ XXX
   # abbreviated long option as short option).
   attr_accessor :require_exact
 
+  # Whether to raise at unknown option.
+  attr_accessor :raise_unknown
+
   #
   # Heading banner preceding summary.
   #
@@ -1502,7 +1506,7 @@ XXX
         style = notwice(default_style.guess(arg = o), style, 'style')
         default_pattern, conv = search(:atype, Object) unless default_pattern
       else
-        desc.push(o)
+        desc.push(o) if o && !o.empty?
       end
     end
 
@@ -1639,9 +1643,11 @@ XXX
           begin
             sw, = complete(:long, opt, true)
             if require_exact && !sw.long.include?(arg)
+              throw :terminate, arg unless raise_unknown
               raise InvalidOption, arg
             end
           rescue ParseError
+            throw :terminate, arg unless raise_unknown
             raise $!.set_option(arg, true)
           end
           begin
@@ -1673,6 +1679,7 @@ XXX
               end
             end
           rescue ParseError
+            throw :terminate, arg unless raise_unknown
             raise $!.set_option(arg, true)
           end
           begin
@@ -1903,10 +1910,13 @@ XXX
   # directory ~/.options, then the basename with '.options' suffix
   # under XDG and Haiku standard places.
   #
-  def load(filename = nil)
+  # The optional +into+ keyword argument works exactly like that accepted in
+  # method #parse.
+  #
+  def load(filename = nil, into: nil)
     unless filename
       basename = File.basename($0, '.*')
-      return true if load(File.expand_path(basename, '~/.options')) rescue nil
+      return true if load(File.expand_path(basename, '~/.options'), into: into) rescue nil
       basename << ".options"
       return [
         # XDG
@@ -1918,11 +1928,11 @@ XXX
         '~/config/settings',
       ].any? {|dir|
         next if !dir or dir.empty?
-        load(File.expand_path(basename, dir)) rescue nil
+        load(File.expand_path(basename, dir), into: into) rescue nil
       }
     end
     begin
-      parse(*IO.readlines(filename).each {|s| s.chomp!})
+      parse(*File.readlines(filename, chomp: true), into: into)
       true
     rescue Errno::ENOENT, Errno::ENOTDIR
       false
@@ -2074,10 +2084,23 @@ XXX
       f |= Regexp::IGNORECASE if /i/ =~ o
       f |= Regexp::MULTILINE if /m/ =~ o
       f |= Regexp::EXTENDED if /x/ =~ o
-      k = o.delete("imx")
-      k = nil if k.empty?
+      case o = o.delete("imx")
+      when ""
+      when "u"
+        s = s.encode(Encoding::UTF_8)
+      when "e"
+        s = s.encode(Encoding::EUC_JP)
+      when "s"
+        s = s.encode(Encoding::SJIS)
+      when "n"
+        f |= Regexp::NOENCODING
+      else
+        raise OptionParser::InvalidArgument, "unknown regexp option - #{o}"
+      end
+    else
+      s ||= all
     end
-    Regexp.new(s || all, f, k)
+    Regexp.new(s, f)
   end
 
   #
diff --git a/lib/pp.gemspec b/lib/pp.gemspec
index d4b0be83df..3f08f400c4 100644
--- a/lib/pp.gemspec
+++ b/lib/pp.gemspec
@@ -1,6 +1,6 @@
 Gem::Specification.new do |spec|
   spec.name          = "pp"
-  spec.version       = "0.3.0"
+  spec.version       = "0.4.0"
   spec.authors       = ["Tanaka Akira"]
   spec.email         = ["akr@fsij.org"]
 
diff --git a/lib/pp.rb b/lib/pp.rb
index f43356a3df..81551aa116 100644
--- a/lib/pp.rb
+++ b/lib/pp.rb
@@ -416,6 +416,26 @@ class Struct # :nodoc:
   end
 end
 
+class Data # :nodoc:
+  def pretty_print(q) # :nodoc:
+    q.group(1, sprintf("#<data %s", PP.mcall(self, Kernel, :class).name), '>') {
+      q.seplist(PP.mcall(self, Data, :members), lambda { q.text "," }) {|member|
+        q.breakable
+        q.text member.to_s
+        q.text '='
+        q.group(1) {
+          q.breakable ''
+          q.pp public_send(member)
+        }
+      }
+    }
+  end
+
+  def pretty_print_cycle(q) # :nodoc:
+    q.text sprintf("#<data %s:...>", PP.mcall(self, Kernel, :class).name)
+  end
+end if "3.2" <= RUBY_VERSION
+
 class Range # :nodoc:
   def pretty_print(q) # :nodoc:
     q.pp self.begin
diff --git a/lib/pstore.rb b/lib/pstore.rb
index a46bcb84bc..72deaa1017 100644
--- a/lib/pstore.rb
+++ b/lib/pstore.rb
@@ -10,89 +10,323 @@
 
 require "digest"
 
-#
-# PStore implements a file based persistence mechanism based on a Hash.  User
-# code can store hierarchies of Ruby objects (values) into the data store file
-# by name (keys).  An object hierarchy may be just a single object.  User code
-# may later read values back from the data store or even update data, as needed.
+# \PStore implements a file based persistence mechanism based on a Hash.
+# User code can store hierarchies of Ruby objects (values)
+# into the data store by name (keys).
+# An object hierarchy may be just a single object.
+# User code may later read values back from the data store
+# or even update data, as needed.
 #
 # The transactional behavior ensures that any changes succeed or fail together.
-# This can be used to ensure that the data store is not left in a transitory
-# state, where some values were updated but others were not.
+# This can be used to ensure that the data store is not left in a transitory state,
+# where some values were updated but others were not.
+#
+# Behind the scenes, Ruby objects are stored to the data store file with Marshal.
+# That carries the usual limitations. Proc objects cannot be marshalled,
+# for example.
+#
+# There are three important concepts here (details at the links):
+#
+# - {Store}[rdoc-ref:PStore@The+Store]: a store is an instance of \PStore.
+# - {Entries}[rdoc-ref:PStore@Entries]: the store is hash-like;
+#   each entry is the key for a stored object.
+# - {Transactions}[rdoc-ref:PStore@Transactions]: each transaction is a collection
+#   of prospective changes to the store;
+#   a transaction is defined in the block given with a call
+#   to PStore#transaction.
+#
+# == About the Examples
+#
+# Examples on this page need a store that has known properties.
+# They can get a new (and populated) store by calling thus:
+#
+#   example_store do |store|
+#     # Example code using store goes here.
+#   end
+#
+# All we really need to know about +example_store+
+# is that it yields a fresh store with a known population of entries;
+# its implementation:
+#
+#   require 'pstore'
+#   require 'tempfile'
+#   # Yield a pristine store for use in examples.
+#   def example_store
+#     # Create the store in a temporary file.
+#     Tempfile.create do |file|
+#       store = PStore.new(file)
+#       # Populate the store.
+#       store.transaction do
+#         store[:foo] = 0
+#         store[:bar] = 1
+#         store[:baz] = 2
+#       end
+#       yield store
+#     end
+#   end
+#
+# == The Store
+#
+# The contents of the store are maintained in a file whose path is specified
+# when the store is created (see PStore.new).
+# The objects are stored and retrieved using
+# module Marshal, which means that certain objects cannot be added to the store;
+# see {Marshal::dump}[rdoc-ref:Marshal.dump].
+#
+# == Entries
+#
+# A store may have any number of entries.
+# Each entry has a key and a value, just as in a hash:
+#
+# - Key: as in a hash, the key can be (almost) any object;
+#   see {Hash Keys}[rdoc-ref:Hash@Hash+Keys].
+#   You may find it convenient to keep it simple by using only
+#   symbols or strings as keys.
+# - Value: the value may be any object that can be marshalled by \Marshal
+#   (see {Marshal::dump}[rdoc-ref:Marshal.dump])
+#   and in fact may be a collection
+#   (e.g., an array, a hash, a set, a range, etc).
+#   That collection may in turn contain nested objects,
+#   including collections, to any depth;
+#   those objects must also be \Marshal-able.
+#   See {Hierarchical Values}[rdoc-ref:PStore@Hierarchical+Values].
+#
+# == Transactions
+#
+# === The Transaction Block
+#
+# The block given with a call to method #transaction#
+# contains a _transaction_,
+# which consists of calls to \PStore methods that
+# read from or write to the store
+# (that is, all \PStore methods except #transaction itself,
+# #path, and Pstore.new):
+#
+#   example_store do |store|
+#     store.transaction do
+#       store.keys # => [:foo, :bar, :baz]
+#       store[:bat] = 3
+#       store.keys # => [:foo, :bar, :baz, :bat]
+#     end
+#   end
+#
+# Execution of the transaction is deferred until the block exits,
+# and is executed _atomically_ (all-or-nothing):
+# either all transaction calls are executed, or none are.
+# This maintains the integrity of the store.
+#
+# Other code in the block (including even calls to #path and PStore.new)
+# is executed immediately, not deferred.
+#
+# The transaction block:
+#
+# - May not contain a nested call to #transaction.
+# - Is the only context where methods that read from or write to
+#   the store are allowed.
+#
+# As seen above, changes in a transaction are made automatically
+# when the block exits.
+# The block may be exited early by calling method #commit or #abort.
+#
+# - Method #commit triggers the update to the store and exits the block:
+#
+#     example_store do |store|
+#       store.transaction do
+#         store.keys # => [:foo, :bar, :baz]
+#         store[:bat] = 3
+#         store.commit
+#         fail 'Cannot get here'
+#       end
+#       store.transaction do
+#         # Update was completed.
+#         store.keys # => [:foo, :bar, :baz, :bat]
+#       end
+#     end
+#
+# - Method #abort discards the update to the store and exits the block:
+#
+#     example_store do |store|
+#       store.transaction do
+#         store.keys # => [:foo, :bar, :baz]
+#         store[:bat] = 3
+#         store.abort
+#         fail 'Cannot get here'
+#       end
+#       store.transaction do
+#         # Update was not completed.
+#         store.keys # => [:foo, :bar, :baz]
+#       end
+#     end
+#
+# === Read-Only Transactions
+#
+# By default, a transaction allows both reading from and writing to
+# the store:
+#
+#   store.transaction do
+#     # Read-write transaction.
+#     # Any code except a call to #transaction is allowed here.
+#   end
+#
+# If argument +read_only+ is passed as +true+,
+# only reading is allowed:
+#
+#   store.transaction(true) do
+#     # Read-only transaction:
+#     # Calls to #transaction, #[]=, and #delete are not allowed here.
+#   end
+#
+# == Hierarchical Values
+#
+# The value for an entry may be a simple object (as seen above).
+# It may also be a hierarchy of objects nested to any depth:
+#
+#   deep_store = PStore.new('deep.store')
+#   deep_store.transaction do
+#     array_of_hashes = [{}, {}, {}]
+#     deep_store[:array_of_hashes] = array_of_hashes
+#     deep_store[:array_of_hashes] # => [{}, {}, {}]
+#     hash_of_arrays = {foo: [], bar: [], baz: []}
+#     deep_store[:hash_of_arrays] = hash_of_arrays
+#     deep_store[:hash_of_arrays]  # => {:foo=>[], :bar=>[], :baz=>[]}
+#     deep_store[:hash_of_arrays][:foo].push(:bat)
+#     deep_store[:hash_of_arrays]  # => {:foo=>[:bat], :bar=>[], :baz=>[]}
+#   end
+#
+# And recall that you can use
+# {dig methods}[rdoc-ref:dig_methods.rdoc]
+# in a returned hierarchy of objects.
+#
+# == Working with the Store
+#
+# === Creating a Store
+#
+# Use method PStore.new to create a store.
+# The new store creates or opens its containing file:
+#
+#   store = PStore.new('t.store')
+#
+# === Modifying the Store
+#
+# Use method #[]= to update or create an entry:
+#
+#   example_store do |store|
+#     store.transaction do
+#       store[:foo] = 1 # Update.
+#       store[:bam] = 1 # Create.
+#     end
+#   end
+#
+# Use method #delete to remove an entry:
+#
+#   example_store do |store|
+#     store.transaction do
+#       store.delete(:foo)
+#       store[:foo] # => nil
+#     end
+#   end
+#
+# === Retrieving Values
+#
+# Use method #fetch (allows default) or #[] (defaults to +nil+)
+# to retrieve an entry:
+#
+#   example_store do |store|
+#     store.transaction do
+#       store[:foo]             # => 0
+#       store[:nope]            # => nil
+#       store.fetch(:baz)       # => 2
+#       store.fetch(:nope, nil) # => nil
+#       store.fetch(:nope)      # Raises exception.
+#     end
+#   end
+#
+# === Querying the Store
+#
+# Use method #key? to determine whether a given key exists:
 #
-# Behind the scenes, Ruby objects are stored to the data store file with
-# Marshal.  That carries the usual limitations.  Proc objects cannot be
-# marshalled, for example.
+#   example_store do |store|
+#     store.transaction do
+#       store.key?(:foo) # => true
+#     end
+#   end
 #
-# == Usage example:
+# Use method #keys to retrieve keys:
+#
+#   example_store do |store|
+#     store.transaction do
+#       store.keys # => [:foo, :bar, :baz]
+#     end
+#   end
+#
+# Use method #path to retrieve the path to the store's underlying file;
+# this method may be called from outside a transaction block:
+#
+#   store = PStore.new('t.store')
+#   store.path # => "t.store"
+#
+# == Transaction Safety
+#
+# For transaction safety, see:
+#
+# - Optional argument +thread_safe+ at method PStore.new.
+# - Attribute #ultra_safe.
+#
+# Needless to say, if you're storing valuable data with \PStore, then you should
+# backup the \PStore file from time to time.
+#
+# == An Example Store
 #
 #  require "pstore"
 #
-#  # a mock wiki object...
+#  # A mock wiki object.
 #  class WikiPage
-#    def initialize( page_name, author, contents )
+#
+#    attr_reader :page_name
+#
+#    def initialize(page_name, author, contents)
 #      @page_name = page_name
 #      @revisions = Array.new
-#
 #      add_revision(author, contents)
 #    end
 #
-#    attr_reader :page_name
-#
-#    def add_revision( author, contents )
-#      @revisions << { :created  => Time.now,
-#                      :author   => author,
-#                      :contents => contents }
+#    def add_revision(author, contents)
+#      @revisions << {created: Time.now,
+#                     author: author,
+#                     contents: contents}
 #    end
 #
 #    def wiki_page_references
 #      [@page_name] + @revisions.last[:contents].scan(/\b(?:[A-Z]+[a-z]+){2,}/)
 #    end
 #
-#    # ...
 #  end
 #
-#  # create a new page...
-#  home_page = WikiPage.new( "HomePage", "James Edward Gray II",
-#                            "A page about the JoysOfDocumentation..." )
+#  # Create a new wiki page.
+#  home_page = WikiPage.new("HomePage", "James Edward Gray II",
+#                           "A page about the JoysOfDocumentation..." )
 #
-#  # then we want to update page data and the index together, or not at all...
 #  wiki = PStore.new("wiki_pages.pstore")
-#  wiki.transaction do  # begin transaction; do all of this or none of it
-#    # store page...
+#  # Update page data and the index together, or not at all.
+#  wiki.transaction do
+#    # Store page.
 #    wiki[home_page.page_name] = home_page
-#    # ensure that an index has been created...
+#    # Create page index.
 #    wiki[:wiki_index] ||= Array.new
-#    # update wiki index...
+#    # Update wiki index.
 #    wiki[:wiki_index].push(*home_page.wiki_page_references)
-#  end                   # commit changes to wiki data store file
-#
-#  ### Some time later... ###
+#  end
 #
-#  # read wiki data...
-#  wiki.transaction(true) do  # begin read-only transaction, no changes allowed
-#    wiki.roots.each do |data_root_name|
-#      p data_root_name
-#      p wiki[data_root_name]
+#  # Read wiki data, setting argument read_only to true.
+#  wiki.transaction(true) do
+#    wiki.keys.each do |key|
+#      puts key
+#      puts wiki[key]
 #    end
 #  end
 #
-# == Transaction modes
-#
-# By default, file integrity is only ensured as long as the operating system
-# (and the underlying hardware) doesn't raise any unexpected I/O errors. If an
-# I/O error occurs while PStore is writing to its file, then the file will
-# become corrupted.
-#
-# You can prevent this by setting <em>pstore.ultra_safe = true</em>.
-# However, this results in a minor performance loss, and only works on platforms
-# that support atomic file renames. Please consult the documentation for
-# +ultra_safe+ for details.
-#
-# Needless to say, if you're storing valuable data with PStore, then you should
-# backup the PStore files from time to time.
 class PStore
-  VERSION = "0.1.1"
+  VERSION = "0.1.2"
 
   RDWR_ACCESS = {mode: IO::RDWR | IO::CREAT | IO::BINARY, encoding: Encoding::ASCII_8BIT}.freeze
   RD_ACCESS = {mode: IO::RDONLY | IO::BINARY, encoding: Encoding::ASCII_8BIT}.freeze
@@ -102,21 +336,38 @@ class PStore
   class Error < StandardError
   end
 
-  # Whether PStore should do its best to prevent file corruptions, even when under
-  # unlikely-to-occur error conditions such as out-of-space conditions and other
-  # unusual OS filesystem errors. Setting this flag comes at the price in the form
-  # of a performance loss.
+  # Whether \PStore should do its best to prevent file corruptions,
+  # even when an unlikely error (such as memory-error or filesystem error) occurs:
+  #
+  # - +true+: changes are posted by creating a temporary file,
+  #   writing the updated data to it, then renaming the file to the given #path.
+  #   File integrity is maintained.
+  #   Note: has effect only if the filesystem has atomic file rename
+  #   (as do POSIX platforms Linux, MacOS, FreeBSD and others).
+  #
+  # - +false+ (the default): changes are posted by rewinding the open file
+  #   and writing the updated data.
+  #   File integrity is maintained if the filesystem raises
+  #   no unexpected I/O error;
+  #   if such an error occurs during a write to the store,
+  #   the file may become corrupted.
   #
-  # This flag only has effect on platforms on which file renames are atomic (e.g.
-  # all POSIX platforms: Linux, MacOS X, FreeBSD, etc). The default value is false.
   attr_accessor :ultra_safe
 
+  # Returns a new \PStore object.
   #
-  # To construct a PStore object, pass in the _file_ path where you would like
-  # the data to be stored.
+  # Argument +file+ is the path to the file in which objects are to be stored;
+  # if the file exists, it should be one that was written by \PStore.
   #
-  # PStore objects are always reentrant. But if _thread_safe_ is set to true,
-  # then it will become thread-safe at the cost of a minor performance hit.
+  #   path = 't.store'
+  #   store = PStore.new(path)
+  #
+  # A \PStore object is
+  # {reentrant}[https://en.wikipedia.org/wiki/Reentrancy_(computing)].
+  # If argument +thread_safe+ is given as +true+,
+  # the object is also thread-safe (at the cost of a small performance penalty):
+  #
+  #   store = PStore.new(path, true)
   #
   def initialize(file, thread_safe = false)
     dir = File::dirname(file)
@@ -147,169 +398,160 @@ class PStore
   end
   private :in_transaction, :in_transaction_wr
 
+  # Returns the value for the given +key+ if the key exists.
+  # +nil+ otherwise;
+  # if not +nil+, the returned value is an object or a hierarchy of objects:
+  #
+  #   example_store do |store|
+  #     store.transaction do
+  #       store[:foo]  # => 0
+  #       store[:nope] # => nil
+  #     end
+  #   end
   #
-  # Retrieves a value from the PStore file data, by _name_.  The hierarchy of
-  # Ruby objects stored under that root _name_ will be returned.
+  # Returns +nil+ if there is no such key.
   #
-  # *WARNING*:  This method is only valid in a PStore#transaction.  It will
-  # raise PStore::Error if called at any other time.
+  # See also {Hierarchical Values}[rdoc-ref:PStore@Hierarchical+Values].
   #
-  def [](name)
+  # Raises an exception if called outside a transaction block.
+  def [](key)
     in_transaction
-    @table[name]
+    @table[key]
   end
+
+  # Like #[], except that it accepts a default value for the store.
+  # If the +key+ does not exist:
   #
-  # This method is just like PStore#[], save that you may also provide a
-  # _default_ value for the object.  In the event the specified _name_ is not
-  # found in the data store, your _default_ will be returned instead.  If you do
-  # not specify a default, PStore::Error will be raised if the object is not
-  # found.
+  # - Raises an exception if +default+ is +PStore::Error+.
+  # - Returns the value of +default+ otherwise:
   #
-  # *WARNING*:  This method is only valid in a PStore#transaction.  It will
-  # raise PStore::Error if called at any other time.
+  #     example_store do |store|
+  #       store.transaction do
+  #         store.fetch(:nope, nil) # => nil
+  #         store.fetch(:nope)      # Raises an exception.
+  #       end
+  #     end
   #
-  def fetch(name, default=PStore::Error)
+  # Raises an exception if called outside a transaction block.
+  def fetch(key, default=PStore::Error)
     in_transaction
-    unless @table.key? name
+    unless @table.key? key
       if default == PStore::Error
-        raise PStore::Error, format("undefined root name `%s'", name)
+        raise PStore::Error, format("undefined key `%s'", key)
       else
         return default
       end
     end
-    @table[name]
+    @table[key]
   end
+
+  # Creates or replaces the value for the given +key+:
   #
-  # Stores an individual Ruby object or a hierarchy of Ruby objects in the data
-  # store file under the root _name_.  Assigning to a _name_ already in the data
-  # store clobbers the old data.
-  #
-  # == Example:
-  #
-  #  require "pstore"
-  #
-  #  store = PStore.new("data_file.pstore")
-  #  store.transaction do  # begin transaction
-  #    # load some data into the store...
-  #    store[:single_object] = "My data..."
-  #    store[:obj_hierarchy] = { "Kev Jackson" => ["rational.rb", "pstore.rb"],
-  #                              "James Gray"  => ["erb.rb", "pstore.rb"] }
-  #  end                   # commit changes to data store file
+  #   example_store do |store|
+  #     temp.transaction do
+  #       temp[:bat] = 3
+  #     end
+  #   end
   #
-  # *WARNING*:  This method is only valid in a PStore#transaction and it cannot
-  # be read-only.  It will raise PStore::Error if called at any other time.
+  # See also {Hierarchical Values}[rdoc-ref:PStore@Hierarchical+Values].
   #
-  def []=(name, value)
+  # Raises an exception if called outside a transaction block.
+  def []=(key, value)
     in_transaction_wr
-    @table[name] = value
+    @table[key] = value
   end
+
+  # Removes and returns the value at +key+ if it exists:
   #
-  # Removes an object hierarchy from the data store, by _name_.
+  #   example_store do |store|
+  #     store.transaction do
+  #       store[:bat] = 3
+  #       store.delete(:bat)
+  #     end
+  #   end
   #
-  # *WARNING*:  This method is only valid in a PStore#transaction and it cannot
-  # be read-only.  It will raise PStore::Error if called at any other time.
+  # Returns +nil+ if there is no such key.
   #
-  def delete(name)
+  # Raises an exception if called outside a transaction block.
+  def delete(key)
     in_transaction_wr
-    @table.delete name
+    @table.delete key
   end
 
+  # Returns an array of the existing keys:
   #
-  # Returns the names of all object hierarchies currently in the store.
+  #   example_store do |store|
+  #     store.transaction do
+  #       store.keys # => [:foo, :bar, :baz]
+  #     end
+  #   end
   #
-  # *WARNING*:  This method is only valid in a PStore#transaction.  It will
-  # raise PStore::Error if called at any other time.
+  # Raises an exception if called outside a transaction block.
   #
-  def roots
+  # PStore#roots is an alias for PStore#keys.
+  def keys
     in_transaction
     @table.keys
   end
+  alias roots keys
+
+  # Returns +true+ if +key+ exists, +false+ otherwise:
   #
-  # Returns true if the supplied _name_ is currently in the data store.
+  #   example_store do |store|
+  #     store.transaction do
+  #       store.key?(:foo) # => true
+  #     end
+  #   end
   #
-  # *WARNING*:  This method is only valid in a PStore#transaction.  It will
-  # raise PStore::Error if called at any other time.
+  # Raises an exception if called outside a transaction block.
   #
-  def root?(name)
+  # PStore#root? is an alias for PStore#key?.
+  def key?(key)
     in_transaction
-    @table.key? name
+    @table.key? key
   end
-  # Returns the path to the data store file.
+  alias root? key?
+
+  # Returns the string file path used to create the store:
+  #
+  #   store.path # => "flat.store"
+  #
   def path
     @filename
   end
 
+  # Exits the current transaction block, committing any changes
+  # specified in the transaction block.
+  # See {Committing or Aborting}[rdoc-ref:PStore@Committing+or+Aborting].
   #
-  # Ends the current PStore#transaction, committing any changes to the data
-  # store immediately.
-  #
-  # == Example:
-  #
-  #  require "pstore"
-  #
-  #  store = PStore.new("data_file.pstore")
-  #  store.transaction do  # begin transaction
-  #    # load some data into the store...
-  #    store[:one] = 1
-  #    store[:two] = 2
-  #
-  #    store.commit        # end transaction here, committing changes
-  #
-  #    store[:three] = 3   # this change is never reached
-  #  end
-  #
-  # *WARNING*:  This method is only valid in a PStore#transaction.  It will
-  # raise PStore::Error if called at any other time.
-  #
+  # Raises an exception if called outside a transaction block.
   def commit
     in_transaction
     @abort = false
     throw :pstore_abort_transaction
   end
+
+  # Exits the current transaction block, discarding any changes
+  # specified in the transaction block.
+  # See {Committing or Aborting}[rdoc-ref:PStore@Committing+or+Aborting].
   #
-  # Ends the current PStore#transaction, discarding any changes to the data
-  # store.
-  #
-  # == Example:
-  #
-  #  require "pstore"
-  #
-  #  store = PStore.new("data_file.pstore")
-  #  store.transaction do  # begin transaction
-  #    store[:one] = 1     # this change is not applied, see below...
-  #    store[:two] = 2     # this change is not applied, see below...
-  #
-  #    store.abort         # end transaction here, discard all changes
-  #
-  #    store[:three] = 3   # this change is never reached
-  #  end
-  #
-  # *WARNING*:  This method is only valid in a PStore#transaction.  It will
-  # raise PStore::Error if called at any other time.
-  #
+  # Raises an exception if called outside a transaction block.
   def abort
     in_transaction
     @abort = true
     throw :pstore_abort_transaction
   end
 
+  # Opens a transaction block for the store.
+  # See {Transactions}[rdoc-ref:PStore@Transactions].
   #
-  # Opens a new transaction for the data store.  Code executed inside a block
-  # passed to this method may read and write data to and from the data store
-  # file.
-  #
-  # At the end of the block, changes are committed to the data store
-  # automatically.  You may exit the transaction early with a call to either
-  # PStore#commit or PStore#abort.  See those methods for details about how
-  # changes are handled.  Raising an uncaught Exception in the block is
-  # equivalent to calling PStore#abort.
-  #
-  # If _read_only_ is set to +true+, you will only be allowed to read from the
-  # data store during the transaction and any attempts to change the data will
-  # raise a PStore::Error.
+  # With argument +read_only+ as +false+, the block may both read from
+  # and write to the store.
   #
-  # Note that PStore does not support nested transactions.
+  # With argument +read_only+ as +true+, the block may not include calls
+  # to #transaction, #[]=, or #delete.
   #
+  # Raises an exception if called within a transaction block.
   def transaction(read_only = false)  # :yields:  pstore
     value = nil
     if !@thread_safe
diff --git a/lib/racc/info.rb b/lib/racc/info.rb
index bb1f100adc..37bff7edba 100644
--- a/lib/racc/info.rb
+++ b/lib/racc/info.rb
@@ -11,7 +11,7 @@
 #++
 
 module Racc
-  VERSION   = '1.6.0'
+  VERSION   = '1.6.2'
   Version = VERSION
   Copyright = 'Copyright (c) 1999-2006 Minero Aoki'
 end
diff --git a/lib/racc/parser-text.rb b/lib/racc/parser-text.rb
index 4188fa853d..0579f4ce9b 100644
--- a/lib/racc/parser-text.rb
+++ b/lib/racc/parser-text.rb
@@ -22,7 +22,7 @@ module Racc
   class ParseError < StandardError; end
 end
 unless defined?(::ParseError)
-  ParseError = Racc::ParseError
+  ParseError = Racc::ParseError # :nodoc:
 end
 
 # Racc is a LALR(1) parser generator.
diff --git a/lib/racc/parser.rb b/lib/racc/parser.rb
index 4237fb572c..078bfef3e9 100644
--- a/lib/racc/parser.rb
+++ b/lib/racc/parser.rb
@@ -20,7 +20,7 @@ module Racc
   class ParseError < StandardError; end
 end
 unless defined?(::ParseError)
-  ParseError = Racc::ParseError
+  ParseError = Racc::ParseError # :nodoc:
 end
 
 # Racc is a LALR(1) parser generator.
diff --git a/lib/racc/racc.gemspec b/lib/racc/racc.gemspec
index 7ee706f63d..1095c8f47e 100644
--- a/lib/racc/racc.gemspec
+++ b/lib/racc/racc.gemspec
@@ -20,7 +20,7 @@ Racc is a LALR(1) parser generator.
 DESC
   s.authors = ["Minero Aoki", "Aaron Patterson"]
   s.email = [nil, "aaron@tenderlovemaking.com"]
-  s.homepage = "https://i.loveruby.net/en/projects/racc/"
+  s.homepage = "https://github.com/ruby/racc"
   s.licenses = ["Ruby", "BSD-2-Clause"]
   s.executables = ["racc"]
   s.files = [
diff --git a/lib/racc/statetransitiontable.rb b/lib/racc/statetransitiontable.rb
index 4d54287258..d75fa1657a 100644
--- a/lib/racc/statetransitiontable.rb
+++ b/lib/racc/statetransitiontable.rb
@@ -216,7 +216,7 @@ module Racc
         end
         i = ii
       end
-      Regexp.compile(map, 'n')
+      Regexp.compile(map, Regexp::NOENCODING)
     end
 
     def set_table(entries, dummy, tbl, chk, ptr)
diff --git a/lib/random/formatter.rb b/lib/random/formatter.rb
index 744853a4b7..4dea61c16c 100644
--- a/lib/random/formatter.rb
+++ b/lib/random/formatter.rb
@@ -1,9 +1,14 @@
 # -*- coding: us-ascii -*-
 # frozen_string_literal: true
 
-# == Random number formatter.
+# == \Random number formatter.
 #
-# Formats generated random numbers in many manners.
+# Formats generated random numbers in many manners. When <tt>'random/formatter'</tt>
+# is required, several methods are added to empty core module <tt>Random::Formatter</tt>,
+# making them available as Random's instance and module methods.
+#
+# Standard library SecureRandom is also extended with the module, and the methods
+# described below are available as a module methods in it.
 #
 # === Examples
 #
@@ -11,34 +16,45 @@
 #
 #   require 'random/formatter'
 #
+#   prng = Random.new
 #   prng.hex(10) #=> "52750b30ffbc7de3b362"
 #   prng.hex(10) #=> "92b15d6c8dc4beb5f559"
 #   prng.hex(13) #=> "39b290146bea6ce975c37cfc23"
+#   # or just
+#   Random.hex #=> "1aed0c631e41be7f77365415541052ee"
 #
 # Generate random base64 strings:
 #
 #   prng.base64(10) #=> "EcmTPZwWRAozdA=="
 #   prng.base64(10) #=> "KO1nIU+p9DKxGg=="
 #   prng.base64(12) #=> "7kJSM/MzBJI+75j8"
+#   Random.base64(4) #=> "bsQ3fQ=="
 #
 # Generate random binary strings:
 #
 #   prng.random_bytes(10) #=> "\016\t{\370g\310pbr\301"
 #   prng.random_bytes(10) #=> "\323U\030TO\234\357\020\a\337"
+#   Random.random_bytes(6) #=> "\xA1\xE6Lr\xC43"
 #
 # Generate alphanumeric strings:
 #
 #   prng.alphanumeric(10) #=> "S8baxMJnPl"
 #   prng.alphanumeric(10) #=> "aOxAg8BAJe"
+#   Random.alphanumeric #=> "TmP9OsJHJLtaZYhP"
 #
 # Generate UUIDs:
 #
 #   prng.uuid #=> "2d931510-d99f-494a-8c67-87feb05e1594"
 #   prng.uuid #=> "bad85eb9-0713-4da7-8d36-07a8e4b00eab"
+#   Random.uuid #=> "f14e0271-de96-45cc-8911-8910292a42cd"
+#
+# All methods are available in the standard library SecureRandom, too:
+#
+#   SecureRandom.hex #=> "05b45376a30c67238eb93b16499e50cf"
 
 module Random::Formatter
 
-  # Random::Formatter#random_bytes generates a random binary string.
+  # Generate a random binary string.
   #
   # The argument _n_ specifies the length of the result string.
   #
@@ -49,14 +65,16 @@ module Random::Formatter
   #
   #   require 'random/formatter'
   #
-  #   prng.random_bytes #=> "\xD8\\\xE0\xF4\r\xB2\xFC*WM\xFF\x83\x18\xF45\xB6"
+  #   Random.random_bytes #=> "\xD8\\\xE0\xF4\r\xB2\xFC*WM\xFF\x83\x18\xF45\xB6"
+  #   # or
+  #   prng = Random.new
   #   prng.random_bytes #=> "m\xDC\xFC/\a\x00Uf\xB2\xB2P\xBD\xFF6S\x97"
   def random_bytes(n=nil)
     n = n ? n.to_int : 16
     gen_random(n)
   end
 
-  # Random::Formatter#hex generates a random hexadecimal string.
+  # Generate a random hexadecimal string.
   #
   # The argument _n_ specifies the length, in bytes, of the random number to be generated.
   # The length of the resulting hexadecimal string is twice of _n_.
@@ -68,13 +86,15 @@ module Random::Formatter
   #
   #   require 'random/formatter'
   #
-  #   prng.hex #=> "eb693ec8252cd630102fd0d0fb7c3485"
+  #   Random.hex #=> "eb693ec8252cd630102fd0d0fb7c3485"
+  #   # or
+  #   prng = Random.new
   #   prng.hex #=> "91dc3bfb4de5b11d029d376634589b61"
   def hex(n=nil)
     random_bytes(n).unpack1("H*")
   end
 
-  # Random::Formatter#base64 generates a random base64 string.
+  # Generate a random base64 string.
   #
   # The argument _n_ specifies the length, in bytes, of the random number
   # to be generated. The length of the result string is about 4/3 of _n_.
@@ -86,7 +106,9 @@ module Random::Formatter
   #
   #   require 'random/formatter'
   #
-  #   prng.base64 #=> "/2BuBuLf3+WfSKyQbRcc/A=="
+  #   Random.base64 #=> "/2BuBuLf3+WfSKyQbRcc/A=="
+  #   # or
+  #   prng = Random.new
   #   prng.base64 #=> "6BbW0pxO0YENxn38HMUbcQ=="
   #
   # See RFC 3548 for the definition of base64.
@@ -94,7 +116,7 @@ module Random::Formatter
     [random_bytes(n)].pack("m0")
   end
 
-  # Random::Formatter#urlsafe_base64 generates a random URL-safe base64 string.
+  # Generate a random URL-safe base64 string.
   #
   # The argument _n_ specifies the length, in bytes, of the random number
   # to be generated. The length of the result string is about 4/3 of _n_.
@@ -112,7 +134,9 @@ module Random::Formatter
   #
   #   require 'random/formatter'
   #
-  #   prng.urlsafe_base64 #=> "b4GOKm4pOYU_-BOXcrUGDg"
+  #   Random.urlsafe_base64 #=> "b4GOKm4pOYU_-BOXcrUGDg"
+  #   # or
+  #   prng = Random.new
   #   prng.urlsafe_base64 #=> "UZLdOkzop70Ddx-IJR0ABg"
   #
   #   prng.urlsafe_base64(nil, true) #=> "i0XQ-7gglIsHGV2_BNPrdQ=="
@@ -126,12 +150,14 @@ module Random::Formatter
     s
   end
 
-  # Random::Formatter#uuid generates a random v4 UUID (Universally Unique IDentifier).
+  # Generate a random v4 UUID (Universally Unique IDentifier).
   #
   #   require 'random/formatter'
   #
-  #   prng.uuid #=> "2d931510-d99f-494a-8c67-87feb05e1594"
-  #   prng.uuid #=> "bad85eb9-0713-4da7-8d36-07a8e4b00eab"
+  #   Random.uuid #=> "2d931510-d99f-494a-8c67-87feb05e1594"
+  #   Random.uuid #=> "bad85eb9-0713-4da7-8d36-07a8e4b00eab"
+  #   # or
+  #   prng = Random.new
   #   prng.uuid #=> "62936e70-1815-439b-bf89-8492855a7e6b"
   #
   # The version 4 UUID is purely random (except the version).
@@ -139,7 +165,7 @@ module Random::Formatter
   #
   # The result contains 122 random bits (15.25 random bytes).
   #
-  # See RFC 4122 for details of UUID.
+  # See RFC4122[https://datatracker.ietf.org/doc/html/rfc4122] for details of UUID.
   #
   def uuid
     ary = random_bytes(16).unpack("NnnnnN")
@@ -152,7 +178,7 @@ module Random::Formatter
     self.bytes(n)
   end
 
-  # Random::Formatter#choose generates a string that randomly draws from a
+  # Generate a string that randomly draws from a
   # source array of characters.
   #
   # The argument _source_ specifies the array of characters from which
@@ -196,7 +222,7 @@ module Random::Formatter
   end
 
   ALPHANUMERIC = [*'A'..'Z', *'a'..'z', *'0'..'9']
-  # Random::Formatter#alphanumeric generates a random alphanumeric string.
+  # Generate a random alphanumeric string.
   #
   # The argument _n_ specifies the length, in characters, of the alphanumeric
   # string to be generated.
@@ -208,7 +234,9 @@ module Random::Formatter
   #
   #   require 'random/formatter'
   #
-  #   prng.alphanumeric     #=> "2BuBuLf3WfSKyQbR"
+  #   Random.alphanumeric     #=> "2BuBuLf3WfSKyQbR"
+  #   # or
+  #   prng = Random.new
   #   prng.alphanumeric(10) #=> "i6K93NdqiH"
   def alphanumeric(n=nil)
     n = 16 if n.nil?
diff --git a/lib/rdoc/any_method.rb b/lib/rdoc/any_method.rb
index 0b7dd717ab..051f946a10 100644
--- a/lib/rdoc/any_method.rb
+++ b/lib/rdoc/any_method.rb
@@ -350,12 +350,12 @@ class RDoc::AnyMethod < RDoc::MethodAttr
       ignore << is_alias_for.name
       ignore.concat is_alias_for.aliases.map(&:name)
     end
-    ignore.map! { |n| n =~ /\A\[/ ? n[0, 1] : n}
+    ignore.map! { |n| n =~ /\A\[/ ? /\[.*\]/ : n}
     ignore.delete(method_name)
     ignore = Regexp.union(ignore)
 
     matching = entries.reject do |entry|
-      entry =~ /^\w*\.?#{ignore}/ or
+      entry =~ /^\w*\.?#{ignore}[$\(\s]/ or
         entry =~ /\s#{ignore}\s/
     end
 
diff --git a/lib/rdoc/cross_reference.rb b/lib/rdoc/cross_reference.rb
index 0f301dcbb3..319bbc02ac 100644
--- a/lib/rdoc/cross_reference.rb
+++ b/lib/rdoc/cross_reference.rb
@@ -1,4 +1,7 @@
 # frozen_string_literal: true
+
+require_relative 'markup/attribute_manager' # for PROTECT_ATTR
+
 ##
 # RDoc::CrossReference is a reusable way to create cross references for names.
 
@@ -29,7 +32,10 @@ class RDoc::CrossReference
   #
   # See CLASS_REGEXP_STR
 
-  METHOD_REGEXP_STR = /([A-Za-z]\w*[!?=]?|%|=(?:==?|~)|![=~]|\[\]=?|<(?:<|=>?)?|>[>=]?|[-+!]@?|\*\*?|[\/%`|&^~])#{METHOD_ARGS_REGEXP_STR}/.source
+  METHOD_REGEXP_STR = /(
+    (?!\d)[\w#{RDoc::Markup::AttributeManager::PROTECT_ATTR}]+[!?=]?|
+    %|=(?:==?|~)|![=~]|\[\]=?|<(?:<|=>?)?|>[>=]?|[-+!]@?|\*\*?|[\/%\`|&^~]
+  )#{METHOD_ARGS_REGEXP_STR}/.source.delete("\n ").freeze
 
   ##
   # Regular expressions matching text that should potentially have
diff --git a/lib/rdoc/generator/markup.rb b/lib/rdoc/generator/markup.rb
index 41e132450d..b54265717c 100644
--- a/lib/rdoc/generator/markup.rb
+++ b/lib/rdoc/generator/markup.rb
@@ -109,7 +109,7 @@ class RDoc::MethodAttr
     lines.shift if src =~ /\A.*#\ *File/i # remove '# File' comment
     lines.each do |line|
       if line =~ /^ *(?=\S)/
-        n = $&.length
+        n = $~.end(0)
         indent = n if n < indent
         break if n == 0
       end
diff --git a/lib/rdoc/generator/template/darkfish/_head.rhtml b/lib/rdoc/generator/template/darkfish/_head.rhtml
index 4f331245c3..d5aed3e9ef 100644
--- a/lib/rdoc/generator/template/darkfish/_head.rhtml
+++ b/lib/rdoc/generator/template/darkfish/_head.rhtml
@@ -3,18 +3,18 @@
 <title><%= h @title %></title>
 
 <script type="text/javascript">
-  var rdoc_rel_prefix = "<%= asset_rel_prefix %>/";
-  var index_rel_prefix = "<%= rel_prefix %>/";
+  var rdoc_rel_prefix = "<%= h asset_rel_prefix %>/";
+  var index_rel_prefix = "<%= h rel_prefix %>/";
 </script>
 
-<script src="<%= asset_rel_prefix %>/js/navigation.js" defer></script>
-<script src="<%= asset_rel_prefix %>/js/search.js" defer></script>
-<script src="<%= asset_rel_prefix %>/js/search_index.js" defer></script>
-<script src="<%= asset_rel_prefix %>/js/searcher.js" defer></script>
-<script src="<%= asset_rel_prefix %>/js/darkfish.js" defer></script>
+<script src="<%= h asset_rel_prefix %>/js/navigation.js" defer></script>
+<script src="<%= h asset_rel_prefix %>/js/search.js" defer></script>
+<script src="<%= h asset_rel_prefix %>/js/search_index.js" defer></script>
+<script src="<%= h asset_rel_prefix %>/js/searcher.js" defer></script>
+<script src="<%= h asset_rel_prefix %>/js/darkfish.js" defer></script>
 
-<link href="<%= asset_rel_prefix %>/css/fonts.css" rel="stylesheet">
-<link href="<%= asset_rel_prefix %>/css/rdoc.css" rel="stylesheet">
+<link href="<%= h asset_rel_prefix %>/css/fonts.css" rel="stylesheet">
+<link href="<%= h asset_rel_prefix %>/css/rdoc.css" rel="stylesheet">
 <%- @options.template_stylesheets.each do |stylesheet| -%>
-<link href="<%= asset_rel_prefix %>/<%= File.basename stylesheet %>" rel="stylesheet">
+<link href="<%= h asset_rel_prefix %>/<%= File.basename stylesheet %>" rel="stylesheet">
 <%- end -%>
diff --git a/lib/rdoc/generator/template/darkfish/_sidebar_pages.rhtml b/lib/rdoc/generator/template/darkfish/_sidebar_pages.rhtml
index 0ed683ca14..3f68f0c0dc 100644
--- a/lib/rdoc/generator/template/darkfish/_sidebar_pages.rhtml
+++ b/lib/rdoc/generator/template/darkfish/_sidebar_pages.rhtml
@@ -12,18 +12,18 @@
   <%- end.each do |n, files| -%>
     <%- f = files.shift -%>
     <%- if files.empty? -%>
-    <li><a href="<%= rel_prefix %>/<%= f.path %>"><%= h f.page_name %></a>
+    <li><a href="<%= rel_prefix %>/<%= h f.path %>"><%= h f.page_name %></a>
       <%- next -%>
     <%- end -%>
     <li><details<% if dir == n %> open<% end %>><summary><%
     if n == f.page_name
-      %><a href="<%= rel_prefix %>/<%= f.path %>"><%= h n %></a><%
+      %><a href="<%= rel_prefix %>/<%= h f.path %>"><%= h n %></a><%
     else
       %><%= h n %><% files.unshift(f)
     end %></summary>
     <ul class="link-list">
     <%- files.each do |f| -%>
-      <li><a href="<%= rel_prefix %>/<%= f.path %>"><%= h f.page_name %></a>
+      <li><a href="<%= rel_prefix %>/<%= h f.path %>"><%= h f.page_name %></a>
     <%- end -%>
     </ul></details>
   <%- end -%>
diff --git a/lib/rdoc/generator/template/darkfish/_sidebar_table_of_contents.rhtml b/lib/rdoc/generator/template/darkfish/_sidebar_table_of_contents.rhtml
index bf70819f64..b1e047b5f7 100644
--- a/lib/rdoc/generator/template/darkfish/_sidebar_table_of_contents.rhtml
+++ b/lib/rdoc/generator/template/darkfish/_sidebar_table_of_contents.rhtml
@@ -3,16 +3,37 @@
              else
                current.comment
              end
-   table = current.parse(comment).table_of_contents
+   table = current.parse(comment).table_of_contents.dup
 
    if table.length > 1 then %>
 <div class="nav-section">
   <h3>Table of Contents</h3>
 
+    <%- display_link = proc do |heading| -%>
+      <a href="#<%= heading.label current %>"><%= heading.plain_html %></a>
+    <%- end -%>
+
+    <%- list_siblings = proc do -%>
+      <%- level = table.first&.level -%>
+      <%- while table.first && table.first.level >= level -%>
+        <%- heading = table.shift -%>
+        <%- if table.first.nil? || table.first.level <= heading.level -%>
+          <li><% display_link.call heading -%>
+        <%- else -%>
+          <li>
+            <details open>
+              <summary><%- display_link.call heading -%></summary>
+              <ul class="link-list" role="directory">
+                <% list_siblings.call %>
+              </ul>
+            </details>
+          </li>
+        <%- end -%>
+      <%- end -%>
+    <%- end -%>
+
   <ul class="link-list" role="directory">
-<%-   table.each do |heading| -%>
-    <li><a href="#<%= heading.label current %>"><%= heading.plain_html %></a>
-<%-   end -%>
+    <% list_siblings.call %>
   </ul>
 </div>
 <%- end -%>
diff --git a/lib/rdoc/generator/template/darkfish/class.rhtml b/lib/rdoc/generator/template/darkfish/class.rhtml
index 5d7b6a1b80..97d175dddc 100644
--- a/lib/rdoc/generator/template/darkfish/class.rhtml
+++ b/lib/rdoc/generator/template/darkfish/class.rhtml
@@ -98,28 +98,30 @@
 
     <%- methods.each do |method| -%>
       <div id="<%= method.aref %>" class="method-detail <%= method.is_alias_for ? "method-alias" : '' %>">
-        <%- if (call_seq = method.call_seq) then -%>
-        <%-   call_seq.strip.split("\n").each_with_index do |call_seq, i| -%>
-        <div class="method-heading">
-          <span class="method-callseq">
-            <%= h(call_seq.strip.
-                  gsub( /^\w+\./m, '')).
-                  gsub(/(.*)[-=]&gt;/, '\1&rarr;') %>
-          </span>
-          <%- if i == 0 and method.token_stream then -%>
-          <span class="method-click-advice">click to toggle source</span>
-          <%- end -%>
-        </div>
-        <%-   end -%>
-        <%- else -%>
-        <div class="method-heading">
-          <span class="method-name"><%= h method.name %></span><span
-            class="method-args"><%= h method.param_seq %></span>
-          <%- if method.token_stream then -%>
-          <span class="method-click-advice">click to toggle source</span>
+        <div class="method-header">
+          <%- if (call_seq = method.call_seq) then -%>
+          <%-   call_seq.strip.split("\n").each_with_index do |call_seq, i| -%>
+          <div class="method-heading">
+            <span class="method-callseq">
+              <%= h(call_seq.strip.
+                    gsub( /^\w+\./m, '')).
+                    gsub(/(.*)[-=]&gt;/, '\1&rarr;') %>
+            </span>
+            <%- if i == 0 and method.token_stream then -%>
+            <span class="method-click-advice">click to toggle source</span>
+            <%- end -%>
+          </div>
+          <%-   end -%>
+          <%- else -%>
+          <div class="method-heading">
+            <span class="method-name"><%= h method.name %></span><span
+              class="method-args"><%= h method.param_seq %></span>
+            <%- if method.token_stream then -%>
+            <span class="method-click-advice">click to toggle source</span>
+            <%- end -%>
+          </div>
           <%- end -%>
         </div>
-        <%- end -%>
 
         <div class="method-description">
           <%- if method.comment then -%>
diff --git a/lib/rdoc/generator/template/darkfish/index.rhtml b/lib/rdoc/generator/template/darkfish/index.rhtml
index 13fa3dcc7f..423e225b68 100644
--- a/lib/rdoc/generator/template/darkfish/index.rhtml
+++ b/lib/rdoc/generator/template/darkfish/index.rhtml
@@ -17,6 +17,6 @@
       main_page = @files.find { |f| f.full_name == @options.main_page } then %>
 <%= main_page.description %>
 <%- else -%>
-<p>This is the API documentation for <%= @title %>.
+<p>This is the API documentation for <%= h @title %>.
 <%- end -%>
 </main>
diff --git a/lib/rdoc/generator/template/darkfish/js/darkfish.js b/lib/rdoc/generator/template/darkfish/js/darkfish.js
index 111bbf8eb9..d0c9467751 100644
--- a/lib/rdoc/generator/template/darkfish/js/darkfish.js
+++ b/lib/rdoc/generator/template/darkfish/js/darkfish.js
@@ -54,7 +54,7 @@ function hookSearch() {
     var html = '';
 
     // TODO add relative path to <script> per-page
-    html += '<p class="search-match"><a href="' + index_rel_prefix + result.path + '">' + this.hlt(result.title);
+    html += '<p class="search-match"><a href="' + index_rel_prefix + this.escapeHTML(result.path) + '">' + this.hlt(result.title);
     if (result.params)
       html += '<span class="params">' + result.params + '</span>';
     html += '</a>';
diff --git a/lib/rdoc/generator/template/darkfish/js/search.js b/lib/rdoc/generator/template/darkfish/js/search.js
index b558ca5b4f..58e52afecf 100644
--- a/lib/rdoc/generator/template/darkfish/js/search.js
+++ b/lib/rdoc/generator/template/darkfish/js/search.js
@@ -101,7 +101,7 @@ Search.prototype = Object.assign({}, Navigation, new function() {
   }
 
   this.escapeHTML = function(html) {
-    return html.replace(/[&<>]/g, function(c) {
+    return html.replace(/[&<>"`']/g, function(c) {
       return '&#' + c.charCodeAt(0) + ';';
     });
   }
diff --git a/lib/rdoc/generator/template/darkfish/table_of_contents.rhtml b/lib/rdoc/generator/template/darkfish/table_of_contents.rhtml
index 303d7016cc..941ff9d630 100644
--- a/lib/rdoc/generator/template/darkfish/table_of_contents.rhtml
+++ b/lib/rdoc/generator/template/darkfish/table_of_contents.rhtml
@@ -8,14 +8,14 @@
 <ul>
 <%- simple_files.sort.each do |file| -%>
   <li class="file">
-    <a href="<%= file.path %>"><%= h file.page_name %></a>
+    <a href="<%= h file.path %>"><%= h file.page_name %></a>
 <%
    # HACK table_of_contents should not exist on Document
    table = file.parse(file.comment).table_of_contents
    unless table.empty? then %>
     <ul>
 <%- table.each do |heading| -%>
-      <li><a href="<%= file.path %>#<%= heading.aref %>"><%= heading.plain_html %></a>
+      <li><a href="<%= h file.path %>#<%= heading.aref %>"><%= heading.plain_html %></a>
 <%-   end -%>
     </ul>
 <%- end -%>
diff --git a/lib/rdoc/known_classes.rb b/lib/rdoc/known_classes.rb
index 4d7f4aa995..3e8752bbde 100644
--- a/lib/rdoc/known_classes.rb
+++ b/lib/rdoc/known_classes.rb
@@ -25,6 +25,7 @@ module RDoc
     "rb_cObject"           => "Object",
     "rb_cProc"             => "Proc",
     "rb_cRange"            => "Range",
+    "rb_cRefinement"       => "Refinement",
     "rb_cRegexp"           => "Regexp",
     "rb_cRubyVM"           => "RubyVM",
     "rb_cSocket"           => "Socket",
@@ -35,7 +36,7 @@ module RDoc
     "rb_cTime"             => "Time",
     "rb_cTrueClass"        => "TrueClass",
 
-    "rb_eArgError"         => "ArgError",
+    "rb_eArgError"         => "ArgumentError",
     "rb_eEOFError"         => "EOFError",
     "rb_eException"        => "Exception",
     "rb_eFatal"            => "fatal",
@@ -45,8 +46,8 @@ module RDoc
     "rb_eInterrupt"        => "Interrupt",
     "rb_eLoadError"        => "LoadError",
     "rb_eNameError"        => "NameError",
-    "rb_eNoMemError"       => "NoMemError",
-    "rb_eNotImpError"      => "NotImpError",
+    "rb_eNoMemError"       => "NoMemoryError",
+    "rb_eNotImpError"      => "NotImplementedError",
     "rb_eRangeError"       => "RangeError",
     "rb_eRuntimeError"     => "RuntimeError",
     "rb_eScriptError"      => "ScriptError",
@@ -57,7 +58,7 @@ module RDoc
     "rb_eSystemCallError"  => "SystemCallError",
     "rb_eSystemExit"       => "SystemExit",
     "rb_eTypeError"        => "TypeError",
-    "rb_eZeroDivError"     => "ZeroDivError",
+    "rb_eZeroDivError"     => "ZeroDivisionError",
 
     "rb_mComparable"       => "Comparable",
     "rb_mEnumerable"       => "Enumerable",
diff --git a/lib/rdoc/markdown.rb b/lib/rdoc/markdown.rb
index 25a7217d3c..a0709b6352 100644
--- a/lib/rdoc/markdown.rb
+++ b/lib/rdoc/markdown.rb
@@ -209,45 +209,75 @@ class RDoc::Markdown
     attr_accessor :result, :pos
 
     def current_column(target=pos)
-      if c = string.rindex("\n", target-1)
-        return target - c - 1
+      if string[target] == "\n" && (c = string.rindex("\n", target-1) || -1)
+        return target - c
+      elsif c = string.rindex("\n", target)
+        return target - c
       end
 
       target + 1
     end
 
+    def position_line_offsets
+      unless @position_line_offsets
+        @position_line_offsets = []
+        total = 0
+        string.each_line do |line|
+          total += line.size
+          @position_line_offsets << total
+        end
+      end
+      @position_line_offsets
+    end
+
     if [].respond_to? :bsearch_index
       def current_line(target=pos)
-        unless @line_offsets
-          @line_offsets = []
-          total = 0
-          string.each_line do |line|
-            total += line.size
-            @line_offsets << total
-          end
+        if line = position_line_offsets.bsearch_index {|x| x > target }
+          return line + 1
         end
-
-        @line_offsets.bsearch_index {|x| x >= target } + 1 || -1
+        raise "Target position #{target} is outside of string"
       end
     else
       def current_line(target=pos)
-        cur_offset = 0
-        cur_line = 0
-
-        string.each_line do |line|
-          cur_line += 1
-          cur_offset += line.size
-          return cur_line if cur_offset >= target
+        if line = position_line_offsets.index {|x| x > target }
+          return line + 1
         end
 
-        -1
+        raise "Target position #{target} is outside of string"
       end
     end
 
+    def current_character(target=pos)
+      if target < 0 || target >= string.size
+        raise "Target position #{target} is outside of string"
+      end
+      string[target, 1]
+    end
+
+    KpegPosInfo = Struct.new(:pos, :lno, :col, :line, :char)
+
+    def current_pos_info(target=pos)
+      l = current_line target
+      c = current_column target
+      ln = get_line(l-1)
+      chr = string[target,1]
+      KpegPosInfo.new(target, l, c, ln, chr)
+    end
+
     def lines
-      lines = []
-      string.each_line { |l| lines << l }
-      lines
+      string.lines
+    end
+
+    def get_line(no)
+      loff = position_line_offsets
+      if no < 0
+        raise "Line No is out of range: #{no} < 0"
+      elsif no >= loff.size
+        raise "Line No is out of range: #{no} >= #{loff.size}"
+      end
+      lend = loff[no]-1
+      lstart = no > 0 ? loff[no-1] : 0
+      string[lstart..lend]
     end
 
 
@@ -261,6 +291,7 @@ class RDoc::Markdown
       @string = string
       @string_size = string ? string.size : 0
       @pos = pos
+      @position_line_offsets = nil
     end
 
     def show_pos
@@ -285,30 +316,22 @@ class RDoc::Markdown
     end
 
     def failure_caret
-      l = current_line @failing_rule_offset
-      c = current_column @failing_rule_offset
-
-      line = lines[l-1]
-      "#{line}\n#{' ' * (c - 1)}^"
+      p = current_pos_info @failing_rule_offset
+      "#{p.line.chomp}\n#{' ' * (p.col - 1)}^"
     end
 
     def failure_character
-      l = current_line @failing_rule_offset
-      c = current_column @failing_rule_offset
-      lines[l-1][c-1, 1]
+      current_character @failing_rule_offset
     end
 
     def failure_oneline
-      l = current_line @failing_rule_offset
-      c = current_column @failing_rule_offset
-
-      char = lines[l-1][c-1, 1]
+      p = current_pos_info @failing_rule_offset
 
       if @failed_rule.kind_of? Symbol
         info = self.class::Rules[@failed_rule]
-        "@#{l}:#{c} failed rule '#{info.name}', got '#{char}'"
+        "@#{p.lno}:#{p.col} failed rule '#{info.name}', got '#{p.char}'"
       else
-        "@#{l}:#{c} failed rule '#{@failed_rule}', got '#{char}'"
+        "@#{p.lno}:#{p.col} failed rule '#{@failed_rule}', got '#{p.char}'"
       end
     end
 
@@ -321,10 +344,9 @@ class RDoc::Markdown
 
     def show_error(io=STDOUT)
       error_pos = @failing_rule_offset
-      line_no = current_line(error_pos)
-      col_no = current_column(error_pos)
+      p = current_pos_info(error_pos)
 
-      io.puts "On line #{line_no}, column #{col_no}:"
+      io.puts "On line #{p.lno}, column #{p.col}:"
 
       if @failed_rule.kind_of? Symbol
         info = self.class::Rules[@failed_rule]
@@ -333,10 +355,9 @@ class RDoc::Markdown
         io.puts "Failed to match rule '#{@failed_rule}'"
       end
 
-      io.puts "Got: #{string[error_pos,1].inspect}"
-      line = lines[line_no-1]
-      io.puts "=> #{line}"
-      io.print(" " * (col_no + 3))
+      io.puts "Got: #{p.char.inspect}"
+      io.puts "=> #{p.line}"
+      io.print(" " * (p.col + 2))
       io.puts "^"
     end
 
@@ -445,6 +466,7 @@ class RDoc::Markdown
     end
 
     def apply_with_args(rule, *args)
+      @result = nil
       memo_key = [rule, args]
       if m = @memoizations[memo_key][@pos]
         @pos = m.pos
@@ -478,6 +500,7 @@ class RDoc::Markdown
     end
 
     def apply(rule)
+      @result = nil
       if m = @memoizations[rule][@pos]
         @pos = m.pos
         if !m.set
@@ -811,7 +834,7 @@ class RDoc::Markdown
 
       @note_order.each_with_index do |ref, index|
         label = index + 1
-        note = @footnotes[ref]
+        note = @footnotes[ref] or raise ParseError, "footnote [^#{ref}] not found"
 
         link = "{^#{label}}[rdoc-label:footmark-#{label}:foottext-#{label}] "
         note.parts.unshift link
@@ -15533,7 +15556,7 @@ class RDoc::Markdown
     return _tmp
   end
 
-  # RawNoteBlock = @StartList:a (!@BlankLine OptionallyIndentedLine:l { a << l })+ < @BlankLine* > { a << text } { a }
+  # RawNoteBlock = @StartList:a (!@BlankLine !RawNoteReference OptionallyIndentedLine:l { a << l })+ < @BlankLine* > { a << text } { a }
   def _RawNoteBlock
 
     _save = self.pos
@@ -15556,6 +15579,14 @@ class RDoc::Markdown
           self.pos = _save2
           break
         end
+        _save4 = self.pos
+        _tmp = apply(:_RawNoteReference)
+        _tmp = _tmp ? nil : true
+        self.pos = _save4
+        unless _tmp
+          self.pos = _save2
+          break
+        end
         _tmp = apply(:_OptionallyIndentedLine)
         l = @result
         unless _tmp
@@ -15573,26 +15604,34 @@ class RDoc::Markdown
       if _tmp
         while true
 
-          _save4 = self.pos
+          _save5 = self.pos
           while true # sequence
-            _save5 = self.pos
+            _save6 = self.pos
             _tmp = _BlankLine()
             _tmp = _tmp ? nil : true
-            self.pos = _save5
+            self.pos = _save6
             unless _tmp
-              self.pos = _save4
+              self.pos = _save5
+              break
+            end
+            _save7 = self.pos
+            _tmp = apply(:_RawNoteReference)
+            _tmp = _tmp ? nil : true
+            self.pos = _save7
+            unless _tmp
+              self.pos = _save5
               break
             end
             _tmp = apply(:_OptionallyIndentedLine)
             l = @result
             unless _tmp
-              self.pos = _save4
+              self.pos = _save5
               break
             end
             @result = begin;  a << l ; end
             _tmp = true
             unless _tmp
-              self.pos = _save4
+              self.pos = _save5
             end
             break
           end # end sequence
@@ -15894,7 +15933,7 @@ class RDoc::Markdown
     return _tmp
   end
 
-  # Table = &{ github? } TableRow:header TableLine:line TableRow+:body { table = RDoc::Markup::Table.new(header, line, body) }
+  # Table = &{ github? } TableHead:header TableLine:line TableRow+:body { table = RDoc::Markup::Table.new(header, line, body) }
   def _Table
 
     _save = self.pos
@@ -15906,7 +15945,7 @@ class RDoc::Markdown
         self.pos = _save
         break
       end
-      _tmp = apply(:_TableRow)
+      _tmp = apply(:_TableHead)
       header = @result
       unless _tmp
         self.pos = _save
@@ -15950,18 +15989,18 @@ class RDoc::Markdown
     return _tmp
   end
 
-  # TableRow = TableItem+:row "|" @Newline { row }
-  def _TableRow
+  # TableHead = TableItem2+:items "|"? @Newline { items }
+  def _TableHead
 
     _save = self.pos
     while true # sequence
       _save1 = self.pos
       _ary = []
-      _tmp = apply(:_TableItem)
+      _tmp = apply(:_TableItem2)
       if _tmp
         _ary << @result
         while true
-          _tmp = apply(:_TableItem)
+          _tmp = apply(:_TableItem2)
           _ary << @result if _tmp
           break unless _tmp
         end
@@ -15970,13 +16009,18 @@ class RDoc::Markdown
       else
         self.pos = _save1
       end
-      row = @result
+      items = @result
       unless _tmp
         self.pos = _save
         break
       end
+      _save2 = self.pos
       _tmp = match_string("|")
       unless _tmp
+        _tmp = true
+        self.pos = _save2
+      end
+      unless _tmp
         self.pos = _save
         break
       end
@@ -15985,7 +16029,7 @@ class RDoc::Markdown
         self.pos = _save
         break
       end
-      @result = begin;  row ; end
+      @result = begin;  items ; end
       _tmp = true
       unless _tmp
         self.pos = _save
@@ -15993,90 +16037,92 @@ class RDoc::Markdown
       break
     end # end sequence
 
-    set_failed_rule :_TableRow unless _tmp
+    set_failed_rule :_TableHead unless _tmp
     return _tmp
   end
 
-  # TableItem = "|" < (!"|" !@Newline .)+ > { text.strip }
-  def _TableItem
+  # TableRow = ((TableItem:item1 TableItem2*:items { [item1, *items] }):row | TableItem2+:row) "|"? @Newline { row }
+  def _TableRow
 
     _save = self.pos
     while true # sequence
-      _tmp = match_string("|")
-      unless _tmp
-        self.pos = _save
-        break
-      end
-      _text_start = self.pos
+
       _save1 = self.pos
+      while true # choice
 
-      _save2 = self.pos
-      while true # sequence
-        _save3 = self.pos
-        _tmp = match_string("|")
-        _tmp = _tmp ? nil : true
-        self.pos = _save3
-        unless _tmp
-          self.pos = _save2
+        _save2 = self.pos
+        while true # sequence
+          _tmp = apply(:_TableItem)
+          item1 = @result
+          unless _tmp
+            self.pos = _save2
+            break
+          end
+          _ary = []
+          while true
+            _tmp = apply(:_TableItem2)
+            _ary << @result if _tmp
+            break unless _tmp
+          end
+          _tmp = true
+          @result = _ary
+          items = @result
+          unless _tmp
+            self.pos = _save2
+            break
+          end
+          @result = begin;  [item1, *items] ; end
+          _tmp = true
+          unless _tmp
+            self.pos = _save2
+          end
           break
-        end
+        end # end sequence
+
+        row = @result
+        break if _tmp
+        self.pos = _save1
         _save4 = self.pos
-        _tmp = _Newline()
-        _tmp = _tmp ? nil : true
-        self.pos = _save4
-        unless _tmp
-          self.pos = _save2
-          break
-        end
-        _tmp = get_byte
-        unless _tmp
-          self.pos = _save2
+        _ary = []
+        _tmp = apply(:_TableItem2)
+        if _tmp
+          _ary << @result
+          while true
+            _tmp = apply(:_TableItem2)
+            _ary << @result if _tmp
+            break unless _tmp
+          end
+          _tmp = true
+          @result = _ary
+        else
+          self.pos = _save4
         end
+        row = @result
+        break if _tmp
+        self.pos = _save1
         break
-      end # end sequence
-
-      if _tmp
-        while true
-
-          _save5 = self.pos
-          while true # sequence
-            _save6 = self.pos
-            _tmp = match_string("|")
-            _tmp = _tmp ? nil : true
-            self.pos = _save6
-            unless _tmp
-              self.pos = _save5
-              break
-            end
-            _save7 = self.pos
-            _tmp = _Newline()
-            _tmp = _tmp ? nil : true
-            self.pos = _save7
-            unless _tmp
-              self.pos = _save5
-              break
-            end
-            _tmp = get_byte
-            unless _tmp
-              self.pos = _save5
-            end
-            break
-          end # end sequence
+      end # end choice
 
-          break unless _tmp
-        end
+      unless _tmp
+        self.pos = _save
+        break
+      end
+      _save5 = self.pos
+      _tmp = match_string("|")
+      unless _tmp
         _tmp = true
-      else
-        self.pos = _save1
+        self.pos = _save5
       end
-      if _tmp
-        text = get_text(_text_start)
+      unless _tmp
+        self.pos = _save
+        break
       end
+      _tmp = _Newline()
       unless _tmp
         self.pos = _save
         break
       end
-      @result = begin;  text.strip ; end
+      @result = begin;  row ; end
       _tmp = true
       unless _tmp
         self.pos = _save
@@ -16084,46 +16130,46 @@ class RDoc::Markdown
       break
     end # end sequence
 
-    set_failed_rule :_TableItem unless _tmp
+    set_failed_rule :_TableRow unless _tmp
     return _tmp
   end
 
-  # TableLine = TableColumn+:line "|" @Newline { line }
-  def _TableLine
+  # TableItem2 = "|" TableItem
+  def _TableItem2
 
     _save = self.pos
     while true # sequence
-      _save1 = self.pos
-      _ary = []
-      _tmp = apply(:_TableColumn)
-      if _tmp
-        _ary << @result
-        while true
-          _tmp = apply(:_TableColumn)
-          _ary << @result if _tmp
-          break unless _tmp
-        end
-        _tmp = true
-        @result = _ary
-      else
-        self.pos = _save1
-      end
-      line = @result
+      _tmp = match_string("|")
       unless _tmp
         self.pos = _save
         break
       end
-      _tmp = match_string("|")
+      _tmp = apply(:_TableItem)
       unless _tmp
         self.pos = _save
-        break
       end
-      _tmp = _Newline()
+      break
+    end # end sequence
+
+    set_failed_rule :_TableItem2 unless _tmp
+    return _tmp
+  end
+
+  # TableItem = < /(?:\\.|[^|\n])+/ > { text.strip.gsub(/\\(.)/, '\1')  }
+  def _TableItem
+
+    _save = self.pos
+    while true # sequence
+      _text_start = self.pos
+      _tmp = scan(/\G(?-mix:(?:\\.|[^|\n])+)/)
+      if _tmp
+        text = get_text(_text_start)
+      end
       unless _tmp
         self.pos = _save
         break
       end
-      @result = begin;  line ; end
+      @result = begin;  text.strip.gsub(/\\(.)/, '\1')  ; end
       _tmp = true
       unless _tmp
         self.pos = _save
@@ -16131,80 +16177,136 @@ class RDoc::Markdown
       break
     end # end sequence
 
-    set_failed_rule :_TableLine unless _tmp
+    set_failed_rule :_TableItem unless _tmp
     return _tmp
   end
 
-  # TableColumn = "|" < ("-"+ ":"? | ":" "-"*) > { text.start_with?(":") ? :left :                 text.end_with?(":") ? :right : nil               }
-  def _TableColumn
+  # TableLine = ((TableAlign:align1 TableAlign2*:aligns {[align1, *aligns] }):line | TableAlign2+:line) "|"? @Newline { line }
+  def _TableLine
 
     _save = self.pos
     while true # sequence
-      _tmp = match_string("|")
-      unless _tmp
-        self.pos = _save
-        break
-      end
-      _text_start = self.pos
 
       _save1 = self.pos
       while true # choice
 
         _save2 = self.pos
         while true # sequence
-          _save3 = self.pos
-          _tmp = match_string("-")
-          if _tmp
-            while true
-              _tmp = match_string("-")
-              break unless _tmp
-            end
-            _tmp = true
-          else
-            self.pos = _save3
-          end
+          _tmp = apply(:_TableAlign)
+          align1 = @result
           unless _tmp
             self.pos = _save2
             break
           end
-          _save4 = self.pos
-          _tmp = match_string(":")
+          _ary = []
+          while true
+            _tmp = apply(:_TableAlign2)
+            _ary << @result if _tmp
+            break unless _tmp
+          end
+          _tmp = true
+          @result = _ary
+          aligns = @result
           unless _tmp
-            _tmp = true
-            self.pos = _save4
+            self.pos = _save2
+            break
           end
+          @result = begin; [align1, *aligns] ; end
+          _tmp = true
           unless _tmp
             self.pos = _save2
           end
           break
         end # end sequence
 
+        line = @result
         break if _tmp
         self.pos = _save1
-
-        _save5 = self.pos
-        while true # sequence
-          _tmp = match_string(":")
-          unless _tmp
-            self.pos = _save5
-            break
-          end
+        _save4 = self.pos
+        _ary = []
+        _tmp = apply(:_TableAlign2)
+        if _tmp
+          _ary << @result
           while true
-            _tmp = match_string("-")
+            _tmp = apply(:_TableAlign2)
+            _ary << @result if _tmp
             break unless _tmp
           end
           _tmp = true
-          unless _tmp
-            self.pos = _save5
-          end
-          break
-        end # end sequence
-
+          @result = _ary
+        else
+          self.pos = _save4
+        end
+        line = @result
         break if _tmp
         self.pos = _save1
         break
       end # end choice
 
+      unless _tmp
+        self.pos = _save
+        break
+      end
+      _save5 = self.pos
+      _tmp = match_string("|")
+      unless _tmp
+        _tmp = true
+        self.pos = _save5
+      end
+      unless _tmp
+        self.pos = _save
+        break
+      end
+      _tmp = _Newline()
+      unless _tmp
+        self.pos = _save
+        break
+      end
+      @result = begin;  line ; end
+      _tmp = true
+      unless _tmp
+        self.pos = _save
+      end
+      break
+    end # end sequence
+
+    set_failed_rule :_TableLine unless _tmp
+    return _tmp
+  end
+
+  # TableAlign2 = "|" @Sp TableAlign
+  def _TableAlign2
+
+    _save = self.pos
+    while true # sequence
+      _tmp = match_string("|")
+      unless _tmp
+        self.pos = _save
+        break
+      end
+      _tmp = _Sp()
+      unless _tmp
+        self.pos = _save
+        break
+      end
+      _tmp = apply(:_TableAlign)
+      unless _tmp
+        self.pos = _save
+      end
+      break
+    end # end sequence
+
+    set_failed_rule :_TableAlign2 unless _tmp
+    return _tmp
+  end
+
+  # TableAlign = < /:?-+:?/ > @Sp {                 text.start_with?(":") ?                 (text.end_with?(":") ? :center : :left) :                 (text.end_with?(":") ? :right : nil)               }
+  def _TableAlign
+
+    _save = self.pos
+    while true # sequence
+      _text_start = self.pos
+      _tmp = scan(/\G(?-mix::?-+:?)/)
       if _tmp
         text = get_text(_text_start)
       end
@@ -16212,8 +16314,15 @@ class RDoc::Markdown
         self.pos = _save
         break
       end
-      @result = begin;  text.start_with?(":") ? :left :
-                text.end_with?(":") ? :right : nil
+      _tmp = _Sp()
+      unless _tmp
+        self.pos = _save
+        break
+      end
+      @result = begin;
+                text.start_with?(":") ?
+                (text.end_with?(":") ? :center : :left) :
+                (text.end_with?(":") ? :right : nil)
               ; end
       _tmp = true
       unless _tmp
@@ -16222,7 +16331,7 @@ class RDoc::Markdown
       break
     end # end sequence
 
-    set_failed_rule :_TableColumn unless _tmp
+    set_failed_rule :_TableAlign unless _tmp
     return _tmp
   end
 
@@ -16656,13 +16765,16 @@ class RDoc::Markdown
   Rules[:_Note] = rule_info("Note", "&{ notes? } @NonindentSpace RawNoteReference:ref \":\" @Sp @StartList:a RawNoteBlock:i { a.concat i } (&Indent RawNoteBlock:i { a.concat i })* { @footnotes[ref] = paragraph a                    nil                 }")
   Rules[:_InlineNote] = rule_info("InlineNote", "&{ notes? } \"^[\" @StartList:a (!\"]\" Inline:l { a << l })+ \"]\" { ref = [:inline, @note_order.length]                @footnotes[ref] = paragraph a                 note_for ref              }")
   Rules[:_Notes] = rule_info("Notes", "(Note | SkipBlock)*")
-  Rules[:_RawNoteBlock] = rule_info("RawNoteBlock", "@StartList:a (!@BlankLine OptionallyIndentedLine:l { a << l })+ < @BlankLine* > { a << text } { a }")
+  Rules[:_RawNoteBlock] = rule_info("RawNoteBlock", "@StartList:a (!@BlankLine !RawNoteReference OptionallyIndentedLine:l { a << l })+ < @BlankLine* > { a << text } { a }")
   Rules[:_CodeFence] = rule_info("CodeFence", "&{ github? } Ticks3 (@Sp StrChunk:format)? Spnl < ((!\"`\" Nonspacechar)+ | !Ticks3 /`+/ | Spacechar | @Newline)+ > Ticks3 @Sp @Newline* { verbatim = RDoc::Markup::Verbatim.new text               verbatim.format = format.intern if format.instance_of?(String)               verbatim             }")
-  Rules[:_Table] = rule_info("Table", "&{ github? } TableRow:header TableLine:line TableRow+:body { table = RDoc::Markup::Table.new(header, line, body) }")
-  Rules[:_TableRow] = rule_info("TableRow", "TableItem+:row \"|\" @Newline { row }")
-  Rules[:_TableItem] = rule_info("TableItem", "\"|\" < (!\"|\" !@Newline .)+ > { text.strip }")
-  Rules[:_TableLine] = rule_info("TableLine", "TableColumn+:line \"|\" @Newline { line }")
-  Rules[:_TableColumn] = rule_info("TableColumn", "\"|\" < (\"-\"+ \":\"? | \":\" \"-\"*) > { text.start_with?(\":\") ? :left :                 text.end_with?(\":\") ? :right : nil               }")
+  Rules[:_Table] = rule_info("Table", "&{ github? } TableHead:header TableLine:line TableRow+:body { table = RDoc::Markup::Table.new(header, line, body) }")
+  Rules[:_TableHead] = rule_info("TableHead", "TableItem2+:items \"|\"? @Newline { items }")
+  Rules[:_TableRow] = rule_info("TableRow", "((TableItem:item1 TableItem2*:items { [item1, *items] }):row | TableItem2+:row) \"|\"? @Newline { row }")
+  Rules[:_TableItem2] = rule_info("TableItem2", "\"|\" TableItem")
+  Rules[:_TableItem] = rule_info("TableItem", "< /(?:\\\\.|[^|\\n])+/ > { text.strip.gsub(/\\\\(.)/, '\\1')  }")
+  Rules[:_TableLine] = rule_info("TableLine", "((TableAlign:align1 TableAlign2*:aligns {[align1, *aligns] }):line | TableAlign2+:line) \"|\"? @Newline { line }")
+  Rules[:_TableAlign2] = rule_info("TableAlign2", "\"|\" @Sp TableAlign")
+  Rules[:_TableAlign] = rule_info("TableAlign", "< /:?-+:?/ > @Sp {                 text.start_with?(\":\") ?                 (text.end_with?(\":\") ? :center : :left) :                 (text.end_with?(\":\") ? :right : nil)               }")
   Rules[:_DefinitionList] = rule_info("DefinitionList", "&{ definition_lists? } DefinitionListItem+:list { RDoc::Markup::List.new :NOTE, *list.flatten }")
   Rules[:_DefinitionListItem] = rule_info("DefinitionListItem", "DefinitionListLabel+:label DefinitionListDefinition+:defns { list_items = []                        list_items <<                          RDoc::Markup::ListItem.new(label, defns.shift)                         list_items.concat defns.map { |defn|                          RDoc::Markup::ListItem.new nil, defn                        } unless list_items.empty?                         list_items                      }")
   Rules[:_DefinitionListLabel] = rule_info("DefinitionListLabel", "StrChunk:label @Sp @Newline { label }")
diff --git a/lib/rdoc/markdown/literals.rb b/lib/rdoc/markdown/literals.rb
index 4c36672de7..37659b7ae0 100644
--- a/lib/rdoc/markdown/literals.rb
+++ b/lib/rdoc/markdown/literals.rb
@@ -39,45 +39,75 @@ class RDoc::Markdown::Literals
     attr_accessor :result, :pos
 
     def current_column(target=pos)
-      if c = string.rindex("\n", target-1)
-        return target - c - 1
+      if string[target] == "\n" && (c = string.rindex("\n", target-1) || -1)
+        return target - c
+      elsif c = string.rindex("\n", target)
+        return target - c
       end
 
       target + 1
     end
 
+    def position_line_offsets
+      unless @position_line_offsets
+        @position_line_offsets = []
+        total = 0
+        string.each_line do |line|
+          total += line.size
+          @position_line_offsets << total
+        end
+      end
+      @position_line_offsets
+    end
+
     if [].respond_to? :bsearch_index
       def current_line(target=pos)
-        unless @line_offsets
-          @line_offsets = []
-          total = 0
-          string.each_line do |line|
-            total += line.size
-            @line_offsets << total
-          end
+        if line = position_line_offsets.bsearch_index {|x| x > target }
+          return line + 1
         end
-
-        @line_offsets.bsearch_index {|x| x >= target } + 1 || -1
+        raise "Target position #{target} is outside of string"
       end
     else
       def current_line(target=pos)
-        cur_offset = 0
-        cur_line = 0
-
-        string.each_line do |line|
-          cur_line += 1
-          cur_offset += line.size
-          return cur_line if cur_offset >= target
+        if line = position_line_offsets.index {|x| x > target }
+          return line + 1
         end
 
-        -1
+        raise "Target position #{target} is outside of string"
+      end
+    end
+
+    def current_character(target=pos)
+      if target < 0 || target >= string.size
+        raise "Target position #{target} is outside of string"
       end
+      string[target, 1]
+    end
+
+    KpegPosInfo = Struct.new(:pos, :lno, :col, :line, :char)
+
+    def current_pos_info(target=pos)
+      l = current_line target
+      c = current_column target
+      ln = get_line(l-1)
+      chr = string[target,1]
+      KpegPosInfo.new(target, l, c, ln, chr)
     end
 
     def lines
-      lines = []
-      string.each_line { |l| lines << l }
-      lines
+      string.lines
+    end
+
+    def get_line(no)
+      loff = position_line_offsets
+      if no < 0
+        raise "Line No is out of range: #{no} < 0"
+      elsif no >= loff.size
+        raise "Line No is out of range: #{no} >= #{loff.size}"
+      end
+      lend = loff[no]-1
+      lstart = no > 0 ? loff[no-1] : 0
+      string[lstart..lend]
     end
 
 
@@ -91,6 +121,7 @@ class RDoc::Markdown::Literals
       @string = string
       @string_size = string ? string.size : 0
       @pos = pos
+      @position_line_offsets = nil
     end
 
     def show_pos
@@ -115,30 +146,22 @@ class RDoc::Markdown::Literals
     end
 
     def failure_caret
-      l = current_line @failing_rule_offset
-      c = current_column @failing_rule_offset
-
-      line = lines[l-1]
-      "#{line}\n#{' ' * (c - 1)}^"
+      p = current_pos_info @failing_rule_offset
+      "#{p.line.chomp}\n#{' ' * (p.col - 1)}^"
     end
 
     def failure_character
-      l = current_line @failing_rule_offset
-      c = current_column @failing_rule_offset
-      lines[l-1][c-1, 1]
+      current_character @failing_rule_offset
     end
 
     def failure_oneline
-      l = current_line @failing_rule_offset
-      c = current_column @failing_rule_offset
-
-      char = lines[l-1][c-1, 1]
+      p = current_pos_info @failing_rule_offset
 
       if @failed_rule.kind_of? Symbol
         info = self.class::Rules[@failed_rule]
-        "@#{l}:#{c} failed rule '#{info.name}', got '#{char}'"
+        "@#{p.lno}:#{p.col} failed rule '#{info.name}', got '#{p.char}'"
       else
-        "@#{l}:#{c} failed rule '#{@failed_rule}', got '#{char}'"
+        "@#{p.lno}:#{p.col} failed rule '#{@failed_rule}', got '#{p.char}'"
       end
     end
 
@@ -151,10 +174,9 @@ class RDoc::Markdown::Literals
 
     def show_error(io=STDOUT)
       error_pos = @failing_rule_offset
-      line_no = current_line(error_pos)
-      col_no = current_column(error_pos)
+      p = current_pos_info(error_pos)
 
-      io.puts "On line #{line_no}, column #{col_no}:"
+      io.puts "On line #{p.lno}, column #{p.col}:"
 
       if @failed_rule.kind_of? Symbol
         info = self.class::Rules[@failed_rule]
@@ -163,10 +185,9 @@ class RDoc::Markdown::Literals
         io.puts "Failed to match rule '#{@failed_rule}'"
       end
 
-      io.puts "Got: #{string[error_pos,1].inspect}"
-      line = lines[line_no-1]
-      io.puts "=> #{line}"
-      io.print(" " * (col_no + 3))
+      io.puts "Got: #{p.char.inspect}"
+      io.puts "=> #{p.line}"
+      io.print(" " * (p.col + 2))
       io.puts "^"
     end
 
@@ -275,6 +296,7 @@ class RDoc::Markdown::Literals
     end
 
     def apply_with_args(rule, *args)
+      @result = nil
       memo_key = [rule, args]
       if m = @memoizations[memo_key][@pos]
         @pos = m.pos
@@ -308,6 +330,7 @@ class RDoc::Markdown::Literals
     end
 
     def apply(rule)
+      @result = nil
       if m = @memoizations[rule][@pos]
         @pos = m.pos
         if !m.set
diff --git a/lib/rdoc/markup.rb b/lib/rdoc/markup.rb
index 804d24fd2f..6e93030965 100644
--- a/lib/rdoc/markup.rb
+++ b/lib/rdoc/markup.rb
@@ -97,638 +97,7 @@
 #
 # = \RDoc Markup Reference
 #
-# == Block Markup
-#
-# === Paragraphs and Verbatim
-#
-# The markup engine looks for a document's natural left margin.  This is
-# used as the initial margin for the document.
-#
-# Consecutive lines starting at this margin are considered to be a
-# paragraph. Empty lines separate paragraphs.
-#
-# Any line that starts to the right of the current margin is treated
-# as verbatim text.  This is useful for code listings:
-#
-#   3.times { puts "Ruby" }
-#
-# In verbatim text, two or more blank lines are collapsed into one,
-# and trailing blank lines are removed:
-#
-#   This is the first line
-#
-#
-#   This is the second non-blank line,
-#   after 2 blank lines in the source markup.
-#
-#
-# There were two trailing blank lines right above this paragraph, that
-# have been removed. In addition, the verbatim text has been shifted
-# left, so the amount of indentation of verbatim text is unimportant.
-#
-# For HTML output RDoc makes a small effort to determine if a verbatim section
-# contains Ruby source code.  If so, the verbatim block will be marked up as
-# HTML.  Triggers include "def", "class", "module", "require", the "hash
-# rocket"# (=>) or a block call with a parameter.
-#
-# === Headers
-#
-# A line starting with an equal sign (=) is treated as a
-# heading.  Level one headings have one equals sign, level two headings
-# have two, and so on until level six, which is the maximum
-# (seven hyphens or more result in a level six heading).
-#
-# For example, the above header was obtained with:
-#
-#   === Headers
-#
-# In HTML output headers have an id matching their name.  The above example's
-# HTML is:
-#
-#   <h3 id="label-Headers">Headers</h3>
-#
-# If a heading is inside a method body the id will be prefixed with the
-# method's id.  If the above header where in the documentation for a method
-# such as:
-#
-#   ##
-#   # This method does fun things
-#   #
-#   # = Example
-#   #
-#   #   Example of fun things goes here ...
-#
-#   def do_fun_things
-#   end
-#
-# The header's id would be:
-#
-#   <h1 id="method-i-do_fun_things-label-Example">Example</h1>
-#
-# The label can be linked-to using <tt>SomeClass@Headers</tt>.  See
-# {Links}[RDoc::Markup@Links] for further details.
-#
-# === Rules
-#
-# A line starting with three or more hyphens (at the current indent)
-# generates a horizontal rule.
-#
-#   ---
-#
-# produces:
-#
-# ---
-#
-# === Simple Lists
-#
-# If a paragraph starts with a "*", "-", "<digit>." or "<letter>.",
-# then it is taken to be the start of a list.  The margin is increased to be
-# the first non-space following the list start flag.  Subsequent lines
-# should be indented to this new margin until the list ends.  For example:
-#
-#   * this is a list with three paragraphs in
-#     the first item.  This is the first paragraph.
-#
-#     And this is the second paragraph.
-#
-#     1. This is an indented, numbered list.
-#     2. This is the second item in that list
-#
-#     This is the third conventional paragraph in the
-#     first list item.
-#
-#   * This is the second item in the original list
-#
-# produces:
-#
-# * this is a list with three paragraphs in
-#   the first item.  This is the first paragraph.
-#
-#   And this is the second paragraph.
-#
-#   1. This is an indented, numbered list.
-#   2. This is the second item in that list
-#
-#   This is the third conventional paragraph in the
-#   first list item.
-#
-# * This is the second item in the original list
-#
-# === Labeled Lists
-#
-# You can also construct labeled lists, sometimes called description
-# or definition lists.  Do this by putting the label in square brackets
-# and indenting the list body:
-#
-#   [cat]  a small furry mammal
-#          that seems to sleep a lot
-#
-#   [ant]  a little insect that is known
-#          to enjoy picnics
-#
-# produces:
-#
-# [cat]  a small furry mammal
-#        that seems to sleep a lot
-#
-# [ant]  a little insect that is known
-#        to enjoy picnics
-#
-# If you want the list bodies to line up to the left of the labels,
-# use two colons:
-#
-#   cat::  a small furry mammal
-#          that seems to sleep a lot
-#
-#   ant::  a little insect that is known
-#          to enjoy picnics
-#
-# produces:
-#
-# cat::  a small furry mammal
-#        that seems to sleep a lot
-#
-# ant::  a little insect that is known
-#        to enjoy picnics
-#
-# Notice that blank lines right after the label are ignored in labeled lists:
-#
-#   [one]
-#
-#       definition 1
-#
-#   [two]
-#
-#       definition 2
-#
-# produces the same output as
-#
-#   [one]  definition 1
-#   [two]  definition 2
-#
-#
-# === Lists and Verbatim
-#
-# If you want to introduce a verbatim section right after a list, it has to be
-# less indented than the list item bodies, but more indented than the list
-# label, letter, digit or bullet. For instance:
-#
-#   *   point 1
-#
-#   *   point 2, first paragraph
-#
-#       point 2, second paragraph
-#         verbatim text inside point 2
-#       point 2, third paragraph
-#     verbatim text outside of the list (the list is therefore closed)
-#   regular paragraph after the list
-#
-# produces:
-#
-# *   point 1
-#
-# *   point 2, first paragraph
-#
-#     point 2, second paragraph
-#       verbatim text inside point 2
-#     point 2, third paragraph
-#   verbatim text outside of the list (the list is therefore closed)
-# regular paragraph after the list
-#
-# == Text Markup
-#
-# === Bold, Italic, Typewriter Text
-#
-# You can use markup within text (except verbatim) to change the
-# appearance of parts of that text.  Out of the box, RDoc::Markup
-# supports word-based and general markup.
-#
-# Word-based markup uses flag characters around individual words:
-#
-# <tt>\*_word_\*</tt>::  displays _word_ in a *bold* font
-# <tt>\__word_\_</tt>::  displays _word_ in an _emphasized_ font
-# <tt>\+_word_\+</tt>::  displays _word_ in a +code+ font
-#
-# General markup affects text between a start delimiter and an end
-# delimiter.  Not surprisingly, these delimiters look like HTML markup.
-#
-# <tt>\<b>_text_</b></tt>::    displays _text_ in a *bold* font
-# <tt>\<em>_text_</em></tt>::  displays _text_ in an _emphasized_ font
-#                              (alternate tag: <tt>\<i></tt>)
-# <tt>\<tt>_text_\</tt></tt>:: displays _text_ in a +code+ font
-#                              (alternate tag: <tt>\<code></tt>)
-#
-# Unlike conventional Wiki markup, general markup can cross line
-# boundaries.  You can turn off the interpretation of markup by
-# preceding the first character with a backslash (see <i>Escaping
-# Text Markup</i>, below).
-#
-# === Links
-#
-# Links to starting with +http:+, +https:+, +mailto:+, +ftp:+ or +www.+
-# are recognized.  An HTTP url that references an external image is converted
-# into an inline image element.
-#
-# Classes and methods will be automatically linked to their definition.  For
-# example, <tt>RDoc::Markup</tt> will link to this documentation.  By default
-# methods will only be automatically linked if they contain an <tt>_</tt> (all
-# methods can be automatically linked through the <tt>--hyperlink-all</tt>
-# command line option).
-#
-# Single-word methods can be linked by using the <tt>#</tt> character for
-# instance methods or <tt>::</tt> for class methods.  For example,
-# <tt>#convert</tt> links to #convert.  A class or method may be combined like
-# <tt>RDoc::Markup#convert</tt>.
-#
-# A heading inside the documentation can be linked by following the class
-# or method by an <tt>@</tt> then the heading name.
-# <tt>RDoc::Markup@Links</tt> will link to this section like this:
-# RDoc::Markup@Links.  Spaces in headings with multiple words must be escaped
-# with <tt>+</tt> like <tt>RDoc::Markup@Escaping+Text+Markup</tt>.
-# Punctuation and other special characters must be escaped like CGI.escape.
-#
-# The <tt>@</tt> can also be used to link to sections.  If a section and a
-# heading share the same name the section is preferred for the link.
-#
-# Links can also be of the form <tt>label[url]</tt>, in which case +label+ is
-# used in the displayed text, and +url+ is used as the target.  If +label+
-# contains multiple words, put it in braces: <tt>{multi word label}[url]</tt>.
-# The +url+ may be an +http:+-type link or a cross-reference to a class,
-# module or method with a label.
-#
-# Links with the <code>rdoc-image:</code> scheme will create an image tag for
-# HTML output.  Only fully-qualified URLs are supported.
-#
-# Links with the <tt>rdoc-ref:</tt> scheme will link to the referenced class,
-# module, method, file, etc.  If the referenced item is does not exist
-# no link will be generated and <tt>rdoc-ref:</tt> will be removed from the
-# resulting text.
-#
-# Links starting with <tt>rdoc-label:label_name</tt> will link to the
-# +label_name+.  You can create a label for the current link (for
-# bidirectional links) by supplying a name for the current link like
-# <tt>rdoc-label:label-other:label-mine</tt>.
-#
-# Links starting with +link:+ refer to local files whose path is relative to
-# the <tt>--op</tt> directory.  Use <tt>rdoc-ref:</tt> instead of
-# <tt>link:</tt> to link to files generated by RDoc as the link target may
-# be different across RDoc generators.
-#
-# Example links:
-#
-#   https://github.com/ruby/rdoc
-#   mailto:user@example.com
-#   {RDoc Documentation}[http://rdoc.rubyforge.org]
-#   {RDoc Markup}[rdoc-ref:RDoc::Markup]
-#
-# === Escaping Text Markup
-#
-# Text markup can be escaped with a backslash, as in \<tt>, which was obtained
-# with <tt>\\<tt></tt>.  Except in verbatim sections and between \<tt> tags,
-# to produce a backslash you have to double it unless it is followed by a
-# space, tab or newline. Otherwise, the HTML formatter will discard it, as it
-# is used to escape potential links:
-#
-#   * The \ must be doubled if not followed by white space: \\.
-#   * But not in \<tt> tags: in a Regexp, <tt>\S</tt> matches non-space.
-#   * This is a link to {ruby-lang}[www.ruby-lang.org].
-#   * This is not a link, however: \{ruby-lang.org}[www.ruby-lang.org].
-#   * This will not be linked to \RDoc::RDoc#document
-#
-# generates:
-#
-# * The \ must be doubled if not followed by white space: \\.
-# * But not in \<tt> tags: in a Regexp, <tt>\S</tt> matches non-space.
-# * This is a link to {ruby-lang}[www.ruby-lang.org]
-# * This is not a link, however: \{ruby-lang.org}[www.ruby-lang.org]
-# * This will not be linked to \RDoc::RDoc#document
-#
-# Inside \<tt> tags, more precisely, leading backslashes are removed only if
-# followed by a markup character (<tt><*_+</tt>), a backslash, or a known link
-# reference (a known class or method). So in the example above, the backslash
-# of <tt>\S</tt> would be removed if there was a class or module named +S+ in
-# the current context.
-#
-# This behavior is inherited from RDoc version 1, and has been kept for
-# compatibility with existing RDoc documentation.
-#
-# === Conversion of characters
-#
-# HTML will convert two/three dashes to an em-dash. Other common characters are
-# converted as well:
-#
-#   em-dash::  -- or ---
-#   ellipsis:: ...
-#
-#   single quotes:: 'text' or `text'
-#   double quotes:: "text" or ``text''
-#
-#   copyright:: (c)
-#   registered trademark:: (r)
-#
-# produces:
-#
-# em-dash::  -- or ---
-# ellipsis:: ...
-#
-# single quotes:: 'text' or `text'
-# double quotes:: "text" or ``text''
-#
-# copyright:: (c)
-# registered trademark:: (r)
-#
-#
-# == Documenting Source Code
-#
-# Comment blocks can be written fairly naturally, either using <tt>#</tt> on
-# successive lines of the comment, or by including the comment in
-# a <tt>=begin</tt>/<tt>=end</tt> block.  If you use the latter form,
-# the <tt>=begin</tt> line _must_ be flagged with an +rdoc+ tag:
-#
-#   =begin rdoc
-#   Documentation to be processed by RDoc.
-#
-#   ...
-#   =end
-#
-# RDoc stops processing comments if it finds a comment line starting
-# with <tt>--</tt> right after the <tt>#</tt> character (otherwise,
-# it will be treated as a rule if it has three dashes or more).
-# This can be used to separate external from internal comments,
-# or to stop a comment being associated with a method, class, or module.
-# Commenting can be turned back on with a line that starts with <tt>++</tt>.
-#
-#   ##
-#   # Extract the age and calculate the date-of-birth.
-#   #--
-#   # FIXME: fails if the birthday falls on February 29th
-#   #++
-#   # The DOB is returned as a Time object.
-#
-#   def get_dob(person)
-#     # ...
-#   end
-#
-# Names of classes, files, and any method names containing an underscore or
-# preceded by a hash character are automatically linked from comment text to
-# their description. This linking works inside the current class or module,
-# and with ancestor methods (in included modules or in the superclass).
-#
-# Method parameter lists are extracted and displayed with the method
-# description.  If a method calls +yield+, then the parameters passed to yield
-# will also be displayed:
-#
-#   def fred
-#     ...
-#     yield line, address
-#
-# This will get documented as:
-#
-#   fred() { |line, address| ... }
-#
-# You can override this using a comment containing ':yields: ...' immediately
-# after the method definition
-#
-#   def fred # :yields: index, position
-#     # ...
-#
-#     yield line, address
-#
-# which will get documented as
-#
-#    fred() { |index, position| ... }
-#
-# +:yields:+ is an example of a documentation directive.  These appear
-# immediately after the start of the document element they are modifying.
-#
-# RDoc automatically cross-references words with underscores or camel-case.
-# To suppress cross-references, prefix the word with a \ character.  To
-# include special characters like "<tt>\n</tt>", you'll need to use
-# two \ characters in normal text, but only one in \<tt> text:
-#
-#   "\\n" or "<tt>\n</tt>"
-#
-# produces:
-#
-# "\\n" or "<tt>\n</tt>"
-#
-# == Directives
-#
-# Directives are keywords surrounded by ":" characters.
-#
-# === Controlling what is documented
-#
-# [+:nodoc:+ / <tt>:nodoc: all</tt>]
-#   This directive prevents documentation for the element from
-#   being generated.  For classes and modules, methods, aliases,
-#   constants, and attributes directly within the affected class or
-#   module also will be omitted.  By default, though, modules and
-#   classes within that class or module _will_ be documented.  This is
-#   turned off by adding the +all+ modifier.
-#
-#     module MyModule # :nodoc:
-#       class Input
-#       end
-#     end
-#
-#     module OtherModule # :nodoc: all
-#       class Output
-#       end
-#     end
-#
-#   In the above code, only class <tt>MyModule::Input</tt> will be documented.
-#
-#   The +:nodoc:+ directive, like +:enddoc:+, +:stopdoc:+ and +:startdoc:+
-#   presented below, is local to the current file: if you do not want to
-#   document a module that appears in several files, specify +:nodoc:+ on each
-#   appearance, at least once per file.
-#
-# [+:stopdoc:+ / +:startdoc:+]
-#   Stop and start adding new documentation elements to the current container.
-#   For example, if a class has a number of constants that you don't want to
-#   document, put a +:stopdoc:+ before the first, and a +:startdoc:+ after the
-#   last.  If you don't specify a +:startdoc:+ by the end of the container,
-#   disables documentation for the rest of the current file.
-#
-# [+:doc:+]
-#   Forces a method or attribute to be documented even if it wouldn't be
-#   otherwise.  Useful if, for example, you want to include documentation of a
-#   particular private method.
-#
-# [+:enddoc:+]
-#   Document nothing further at the current level: directives +:startdoc:+ and
-#   +:doc:+ that appear after this will not be honored for the current container
-#   (file, class or module), in the current file.
-#
-# [+:notnew:+ / +:not_new:+ / +:not-new:+ ]
-#   Only applicable to the +initialize+ instance method.  Normally RDoc
-#   assumes that the documentation and parameters for +initialize+ are
-#   actually for the +new+ method, and so fakes out a +new+ for the class.
-#   The +:notnew:+ directive stops this.  Remember that +initialize+ is private,
-#   so you won't see the documentation unless you use the +-a+ command line
-#   option.
-#
-# === Method arguments
-#
-# [+:arg:+ or +:args:+ _parameters_]
-#   Overrides the default argument handling with exactly these parameters.
-#
-#     ##
-#     #  :args: a, b
-#
-#     def some_method(*a)
-#     end
-#
-# [+:yield:+ or +:yields:+ _parameters_]
-#   Overrides the default yield discovery with these parameters.
-#
-#     ##
-#     # :yields: key, value
-#
-#     def each_thing &block
-#       @things.each(&block)
-#     end
-#
-# [+:call-seq:+]
-#   Lines up to the next blank line or lines with a common prefix in the
-#   comment are treated as the method's calling sequence, overriding the
-#   default parsing of method parameters and yield arguments.
-#
-#   Multiple lines may be used.
-#
-#     # :call-seq:
-#     #   ARGF.readlines(sep=$/)     -> array
-#     #   ARGF.readlines(limit)      -> array
-#     #   ARGF.readlines(sep, limit) -> array
-#     #
-#     #   ARGF.to_a(sep=$/)     -> array
-#     #   ARGF.to_a(limit)      -> array
-#     #   ARGF.to_a(sep, limit) -> array
-#     #
-#     # The remaining lines are documentation ...
-#
-# === Sections
-#
-# Sections allow you to group methods in a class into sensible containers.  If
-# you use the sections 'Public', 'Internal' and 'Deprecated' (the three
-# allowed method statuses from TomDoc) the sections will be displayed in that
-# order placing the most useful methods at the top.  Otherwise, sections will
-# be displayed in alphabetical order.
-#
-# [+:category:+ _section_]
-#   Adds this item to the named +section+ overriding the current section.  Use
-#   this to group methods by section in RDoc output while maintaining a
-#   sensible ordering (like alphabetical).
-#
-#     # :category: Utility Methods
-#     #
-#     # CGI escapes +text+
-#
-#     def convert_string text
-#       CGI.escapeHTML text
-#     end
-#
-#   An empty category will place the item in the default category:
-#
-#     # :category:
-#     #
-#     # This method is in the default category
-#
-#     def some_method
-#       # ...
-#     end
-#
-#   Unlike the :section: directive, :category: is not sticky.  The category
-#   only applies to the item immediately following the comment.
-#
-#   Use the :section: directive to provide introductory text for a section of
-#   documentation.
-#
-# [+:section:+ _title_]
-#   Provides section introductory text in RDoc output.  The title following
-#   +:section:+ is used as the section name and the remainder of the comment
-#   containing the section is used as introductory text.  A section's comment
-#   block must be separated from following comment blocks.  Use an empty title
-#   to switch to the default section.
-#
-#   The :section: directive is sticky, so subsequent methods, aliases,
-#   attributes, and classes will be contained in this section until the
-#   section is changed.  The :category: directive will override the :section:
-#   directive.
-#
-#   A :section: comment block may have one or more lines before the :section:
-#   directive.  These will be removed, and any identical lines at the end of
-#   the block are also removed.  This allows you to add visual cues to the
-#   section.
-#
-#   Example:
-#
-#     # ----------------------------------------
-#     # :section: My Section
-#     # This is the section that I wrote.
-#     # See it glisten in the noon-day sun.
-#     # ----------------------------------------
-#
-#     ##
-#     # Comment for some_method
-#
-#     def some_method
-#       # ...
-#     end
-#
-# === Other directives
-#
-# [+:markup:+ _type_]
-#   Overrides the default markup type for this comment with the specified
-#   markup type.  For Ruby files, if the first comment contains this directive
-#   it is applied automatically to all comments in the file.
-#
-#   Unless you are converting between markup formats you should use a
-#   <code>.rdoc_options</code> file to specify the default documentation
-#   format for your entire project.  See RDoc::Options@Saved+Options for
-#   instructions.
-#
-#   At the top of a file the +:markup:+ directive applies to the entire file:
-#
-#     # coding: UTF-8
-#     # :markup: TomDoc
-#
-#     # TomDoc comment here ...
-#
-#     class MyClass
-#       # ...
-#
-#   For just one comment:
-#
-#       # ...
-#     end
-#
-#     # :markup: RDoc
-#     #
-#     # This is a comment in RDoc markup format ...
-#
-#     def some_method
-#       # ...
-#
-#   See Markup@CONTRIBUTING for instructions on adding a new markup format.
-#
-# [+:include:+ _filename_]
-#   Include the contents of the named file at this point. This directive
-#   must appear alone on one line, possibly preceded by spaces. In this
-#   position, it can be escaped with a \ in front of the first colon.
-#
-#   The file will be searched for in the directories listed by the +--include+
-#   option, or in the current directory by default.  The contents of the file
-#   will be shifted to have the same indentation as the ':' at the start of
-#   the +:include:+ directive.
-#
-# [+:title:+ _text_]
-#   Sets the title for the document.  Equivalent to the <tt>--title</tt>
-#   command line parameter.  (The command line parameter overrides any :title:
-#   directive in the source).
-#
-# [+:main:+ _name_]
-#   Equivalent to the <tt>--main</tt> command line parameter.
+# See RDoc::MarkupReference.
 #
 #--
 # Original Author:: Dave Thomas,  dave@pragmaticprogrammer.com
diff --git a/lib/rdoc/markup/attribute_manager.rb b/lib/rdoc/markup/attribute_manager.rb
index 6843e6c3d0..601e6bc189 100644
--- a/lib/rdoc/markup/attribute_manager.rb
+++ b/lib/rdoc/markup/attribute_manager.rb
@@ -2,6 +2,17 @@
 ##
 # Manages changes of attributes in a block of text
 
+unless MatchData.method_defined?(:match_length)
+  using Module.new {
+    refine(MatchData) {
+      def match_length(nth)
+        b, e = offset(nth)
+        e - b if b
+      end
+    }
+  }
+end
+
 class RDoc::Markup::AttributeManager
 
   ##
@@ -150,18 +161,20 @@ class RDoc::Markup::AttributeManager
       exclusive == exclusive?(bitmap)
     }.keys
     return if tags.empty?
-    all_tags = @matching_word_pairs.keys
+    tags = "[#{tags.join("")}](?!#{PROTECT_ATTR})"
+    all_tags = "[#{@matching_word_pairs.keys.join("")}](?!#{PROTECT_ATTR})"
 
-    re = /(^|\W|[#{all_tags.join("")}])([#{tags.join("")}])(\2*[#\\]?[\w:.\/\[\]-]+?\S?)\2(?!\2)([#{all_tags.join("")}]|\W|$)/
+    re = /(?:^|\W|#{all_tags})\K(#{tags})(\1*[#\\]?[\w:#{PROTECT_ATTR}.\/\[\]-]+?\S?)\1(?!\1)(?=#{all_tags}|\W|$)/
 
     1 while str.gsub!(re) { |orig|
-      attr = @matching_word_pairs[$2]
-      attr_updated = attrs.set_attrs($`.length + $1.length + $2.length, $3.length, attr)
-      if attr_updated
-        $1 + NULL * $2.length + $3 + NULL * $2.length + $4
+      a, w = (m = $~).values_at(1, 2)
+      attr = @matching_word_pairs[a]
+      if attrs.set_attrs(m.begin(2), w.length, attr)
+        a = NULL * a.length
       else
-        $1 + NON_PRINTING_START + $2 + NON_PRINTING_END + $3 + NON_PRINTING_START + $2 + NON_PRINTING_END + $4
+        a = NON_PRINTING_START + a + NON_PRINTING_END
       end
+      a + w + a
     }
     str.delete!(NON_PRINTING_START + NON_PRINTING_END)
   end
@@ -172,9 +185,10 @@ class RDoc::Markup::AttributeManager
       @word_pair_map.each do |regexp, attr|
         next unless exclusive == exclusive?(attr)
         1 while str.gsub!(regexp) { |orig|
-          updated = attrs.set_attrs($`.length + $1.length, $2.length, attr)
+          w = (m = ($~))[2]
+          updated = attrs.set_attrs(m.begin(2), w.length, attr)
           if updated
-            NULL * $1.length + $2 + NULL * $3.length
+            NULL * m.match_length(1) + w + NULL * m.match_length(3)
           else
             orig
           end
@@ -193,9 +207,9 @@ class RDoc::Markup::AttributeManager
 
     1 while str.gsub!(/<(#{tags})>(.*?)<\/\1>/i) { |orig|
       attr = @html_tags[$1.downcase]
-      html_length = $1.length + 2
+      html_length = $~.match_length(1) + 2 # "<>".length
       seq = NULL * html_length
-      attrs.set_attrs($`.length + html_length, $2.length, attr)
+      attrs.set_attrs($~.begin(2), $~.match_length(2), attr)
       seq + $2 + seq + NULL
     }
   end
diff --git a/lib/rdoc/markup/parser.rb b/lib/rdoc/markup/parser.rb
index 1b54a519d1..0029df7e65 100644
--- a/lib/rdoc/markup/parser.rb
+++ b/lib/rdoc/markup/parser.rb
@@ -287,6 +287,12 @@ class RDoc::Markup::Parser
         line << ' ' * indent
       when :BREAK, :TEXT then
         line << data
+      when :BLOCKQUOTE then
+        line << '>>>'
+        peek_type, _, peek_column = peek_token
+        if peek_type != :NEWLINE and peek_column
+          line << ' ' * (peek_column - column - 3)
+        end
       else # *LIST_TOKENS
         list_marker = case type
                       when :BULLET then data
@@ -372,11 +378,8 @@ class RDoc::Markup::Parser
         unget
         parse_text parent, indent
       when :BLOCKQUOTE then
-        type, _, column = get
-        if type == :NEWLINE
-          type, _, column = get
-        end
-        unget if type
+        nil while (type, = get; type) and type != :NEWLINE
+        _, _, column, = peek_token
         bq = RDoc::Markup::BlockQuote.new
         p :blockquote_start => [data, column] if @debug
         parse bq, column
@@ -544,7 +547,10 @@ class RDoc::Markup::Parser
                    [:NOTE, @s[1], *pos]
                  # >>> followed by end of line => :BLOCKQUOTE
                  when @s.scan(/>>> *(\w+)?$/) then
-                   [:BLOCKQUOTE, @s[1], *pos]
+                   if word = @s[1]
+                     @s.unscan(word)
+                   end
+                   [:BLOCKQUOTE, word, *pos]
                  # anything else: :TEXT
                  else
                    @s.scan(/(.*?)(  )?\r?$/)
diff --git a/lib/rdoc/markup/to_html.rb b/lib/rdoc/markup/to_html.rb
index 7c2e91cecf..bf323074de 100644
--- a/lib/rdoc/markup/to_html.rb
+++ b/lib/rdoc/markup/to_html.rb
@@ -61,12 +61,14 @@ class RDoc::Markup::ToHtml < RDoc::Markup::Formatter
   #
   # These methods are used by regexp handling markup added by RDoc::Markup#add_regexp_handling.
 
+  URL_CHARACTERS_REGEXP_STR = /[A-Za-z0-9\-._~:\/\?#\[\]@!$&'\(\)*+,;%=]/.source
+
   ##
   # Adds regexp handlings.
 
   def init_regexp_handlings
     # external links
-    @markup.add_regexp_handling(/(?:link:|https?:|mailto:|ftp:|irc:|www\.)\S+\w/,
+    @markup.add_regexp_handling(/(?:link:|https?:|mailto:|ftp:|irc:|www\.)#{URL_CHARACTERS_REGEXP_STR}+\w/,
                                 :HYPERLINK)
     init_link_notation_regexp_handlings
   end
@@ -82,7 +84,7 @@ class RDoc::Markup::ToHtml < RDoc::Markup::Formatter
   def handle_RDOCLINK url # :nodoc:
     case url
     when /^rdoc-ref:/
-      $'
+      CGI.escapeHTML($')
     when /^rdoc-label:/
       text = $'
 
@@ -93,13 +95,11 @@ class RDoc::Markup::ToHtml < RDoc::Markup::Formatter
              else                    text
              end
 
-      gen_url url, text
+      gen_url CGI.escapeHTML(url), CGI.escapeHTML(text)
     when /^rdoc-image:/
-      "<img src=\"#{$'}\">"
-    else
-      url =~ /\Ardoc-[a-z]+:/
-
-      $'
+      %[<img src=\"#{CGI.escapeHTML($')}\">]
+    when /\Ardoc-[a-z]+:/
+      CGI.escapeHTML($')
     end
   end
 
@@ -123,7 +123,7 @@ class RDoc::Markup::ToHtml < RDoc::Markup::Formatter
   #   Reference to a local file relative to the output directory.
 
   def handle_regexp_HYPERLINK(target)
-    url = target.text
+    url = CGI.escapeHTML(target.text)
 
     gen_url url, url
   end
@@ -152,9 +152,13 @@ class RDoc::Markup::ToHtml < RDoc::Markup::Formatter
       text =~ /^\{(.*)\}\[(.*?)\]$/ or text =~ /^(\S+)\[(.*?)\]$/
 
     label = $1
-    url   = $2
+    url   = CGI.escapeHTML($2)
 
-    label = handle_RDOCLINK label if /^rdoc-image:/ =~ label
+    if /^rdoc-image:/ =~ label
+      label = handle_RDOCLINK(label)
+    else
+      label = CGI.escapeHTML(label)
+    end
 
     gen_url url, label
   end
@@ -322,7 +326,7 @@ class RDoc::Markup::ToHtml < RDoc::Markup::Formatter
     header.zip(aligns) do |text, align|
       @res << '<th'
       @res << ' align="' << align << '"' if align
-      @res << '>' << CGI.escapeHTML(text) << "</th>\n"
+      @res << '>' << to_html(text) << "</th>\n"
     end
     @res << "</tr>\n</thead>\n<tbody>\n"
     body.each do |row|
@@ -330,7 +334,7 @@ class RDoc::Markup::ToHtml < RDoc::Markup::Formatter
       row.zip(aligns) do |text, align|
         @res << '<td'
         @res << ' align="' << align << '"' if align
-        @res << '>' << CGI.escapeHTML(text) << "</td>\n"
+        @res << '>' << to_html(text) << "</td>\n"
       end
       @res << "</tr>\n"
     end
diff --git a/lib/rdoc/markup/to_rdoc.rb b/lib/rdoc/markup/to_rdoc.rb
index 3cdf4fd08b..2a9b05625c 100644
--- a/lib/rdoc/markup/to_rdoc.rb
+++ b/lib/rdoc/markup/to_rdoc.rb
@@ -330,31 +330,14 @@ class RDoc::Markup::ToRdoc < RDoc::Markup::Formatter
 
     text_len = 20 if text_len < 20
 
-    re = /^(.{0,#{text_len}})[ \n]/
     next_prefix = ' ' * @indent
 
     prefix = @prefix || next_prefix
     @prefix = nil
 
-    @res << prefix
-
-    while text.length > text_len
-      if text =~ re then
-        @res << $1
-        text.slice!(0, $&.length)
-      else
-        @res << text.slice!(0, text_len)
-      end
-
-      @res << "\n" << next_prefix
-    end
-
-    if text.empty? then
-      @res.pop
-      @res.pop
-    else
-      @res << text
-      @res << "\n"
+    text.scan(/\G(?:([^ \n]{#{text_len}})(?=[^ \n])|(.{1,#{text_len}})(?:[ \n]|\z))/) do
+      @res << prefix << ($1 || $2) << "\n"
+      prefix = next_prefix
     end
   end
 
diff --git a/lib/rdoc/options.rb b/lib/rdoc/options.rb
index 55994c9dcc..eed0f6b39b 100644
--- a/lib/rdoc/options.rb
+++ b/lib/rdoc/options.rb
@@ -339,6 +339,10 @@ class RDoc::Options
 
   attr_reader :visibility
 
+  ##
+  # Indicates if files of test suites should be skipped
+  attr_accessor :skip_tests
+
   def initialize loaded_options = nil # :nodoc:
     init_ivars
     override loaded_options if loaded_options
@@ -386,6 +390,7 @@ class RDoc::Options
     @write_options = false
     @encoding = Encoding::UTF_8
     @charset = @encoding.name
+    @skip_tests = true
   end
 
   def init_with map # :nodoc:
@@ -778,6 +783,13 @@ Usage: #{opt.program_name} [options] [names...]
 
       opt.separator nil
 
+      opt.on("--no-skipping-tests", nil,
+             "Don't skip generating documentation for test and spec files") do |value|
+        @skip_tests = false
+      end
+
+      opt.separator nil
+
       opt.on("--extension=NEW=OLD", "-E",
              "Treat files ending with .new as if they",
              "ended with .old. Using '-E cgi=rb' will",
diff --git a/lib/rdoc/parser.rb b/lib/rdoc/parser.rb
index 7006265b63..3bb6f5d1f2 100644
--- a/lib/rdoc/parser.rb
+++ b/lib/rdoc/parser.rb
@@ -266,6 +266,23 @@ class RDoc::Parser
   autoload :RubyTools, "#{__dir__}/parser/ruby_tools"
   autoload :Text,      "#{__dir__}/parser/text"
 
+  ##
+  # Normalizes tabs in +body+
+
+  def handle_tab_width(body)
+    if /\t/ =~ body
+      tab_width = @options.tab_width
+      body.split(/\n/).map do |line|
+        1 while line.gsub!(/\t+/) do
+          b, e = $~.offset(0)
+          ' ' * (tab_width * (e-b) - b % tab_width)
+        end
+        line
+      end.join "\n"
+    else
+      body
+    end
+  end
 end
 
 # simple must come first in order to show up last in the parsers list
diff --git a/lib/rdoc/parser/c.rb b/lib/rdoc/parser/c.rb
index b1bbf22f16..5695bf1acb 100644
--- a/lib/rdoc/parser/c.rb
+++ b/lib/rdoc/parser/c.rb
@@ -122,6 +122,11 @@ class RDoc::Parser::C < RDoc::Parser
 
   include RDoc::Text
 
+  # :stopdoc:
+  BOOL_ARG_PATTERN = /\s*+\b([01]|Q?(?:true|false)|TRUE|FALSE)\b\s*/
+  TRUE_VALUES = ['1', 'TRUE', 'true', 'Qtrue'].freeze
+  # :startdoc:
+
   ##
   # Maps C variable names to names of Ruby classes or modules
 
@@ -259,18 +264,18 @@ class RDoc::Parser::C < RDoc::Parser
     @content.scan(/rb_attr\s*\(
                    \s*(\w+),
                    \s*([\w"()]+),
-                   \s*([01]),
-                   \s*([01]),
-                   \s*\w+\);/xm) do |var_name, attr_name, read, write|
+                   #{BOOL_ARG_PATTERN},
+                   #{BOOL_ARG_PATTERN},
+                   \s*\w+\);/xmo) do |var_name, attr_name, read, write|
       handle_attr var_name, attr_name, read, write
     end
 
     @content.scan(%r%rb_define_attr\(
                              \s*([\w\.]+),
                              \s*"([^"]+)",
-                             \s*(\d+),
-                             \s*(\d+)\s*\);
-                %xm) do |var_name, attr_name, read, write|
+                             #{BOOL_ARG_PATTERN},
+                             #{BOOL_ARG_PATTERN}\);
+                %xmo) do |var_name, attr_name, read, write|
       handle_attr var_name, attr_name, read, write
     end
   end
@@ -367,12 +372,20 @@ class RDoc::Parser::C < RDoc::Parser
         next
       end
 
+      var_name = $~[:var_name]
       type = $~[:module] ? :module : :class
       class_name = $~[:class_name]
       parent_name = $~[:parent_name] || $~[:path]
       under = $~[:under]
+      attributes = $~[:attributes]
 
-      handle_class_module($~[:var_name], type, class_name, parent_name, under)
+      handle_class_module(var_name, type, class_name, parent_name, under)
+      if attributes and !parent_name # rb_struct_define *not* without_accessor
+        true_flag = 'Qtrue'
+        attributes.scan(/"\K\w+(?=")/) do |attr_name|
+          handle_attr var_name, attr_name, true_flag, true_flag
+        end
+      end
     end
   end
 
@@ -715,7 +728,7 @@ class RDoc::Parser::C < RDoc::Parser
         ((?>/\*.*?\*/\s+))
         (static\s+)?
         void\s+
-        Init_#{class_name}\s*(?:_\(\s*)?\(\s*(?:void\s*)?\)%xmi then
+        Init(?:VM)?_(?i:#{class_name})\s*(?:_\(\s*)?\(\s*(?:void\s*)?\)%xm then
       comment = $1.sub(%r%Document-(?:class|module):\s+#{class_name}%, '')
     elsif @content =~ %r%Document-(?:class|module):\s+#{class_name}\s*?
                          (?:<\s+[:,\w]+)?\n((?>.*?\*/))%xm then
@@ -815,8 +828,8 @@ class RDoc::Parser::C < RDoc::Parser
 
   def handle_attr(var_name, attr_name, read, write)
     rw = ''
-    rw += 'R' if '1' == read
-    rw += 'W' if '1' == write
+    rw += 'R' if TRUE_VALUES.include?(read)
+    rw += 'W' if TRUE_VALUES.include?(write)
 
     class_name = @known_classes[var_name]
 
@@ -1045,23 +1058,6 @@ class RDoc::Parser::C < RDoc::Parser
   end
 
   ##
-  # Normalizes tabs in +body+
-
-  def handle_tab_width(body)
-    if /\t/ =~ body
-      tab_width = @options.tab_width
-      body.split(/\n/).map do |line|
-        1 while line.gsub!(/\t+/) do
-          ' ' * (tab_width * $&.length - $`.length % tab_width)
-        end && $~
-        line
-      end.join "\n"
-    else
-      body
-    end
-  end
-
-  ##
   # Loads the variable map with the given +name+ from the RDoc::Store, if
   # present.
 
diff --git a/lib/rdoc/parser/ruby.rb b/lib/rdoc/parser/ruby.rb
index 3c5f79632c..b74ead65ab 100644
--- a/lib/rdoc/parser/ruby.rb
+++ b/lib/rdoc/parser/ruby.rb
@@ -164,15 +164,7 @@ class RDoc::Parser::Ruby < RDoc::Parser
   def initialize(top_level, file_name, content, options, stats)
     super
 
-    if /\t/ =~ content then
-      tab_width = @options.tab_width
-      content = content.split(/\n/).map do |line|
-        1 while line.gsub!(/\t+/) {
-          ' ' * (tab_width*$&.length - $`.length % tab_width)
-        }  && $~
-        line
-      end.join("\n")
-    end
+    content = handle_tab_width(content)
 
     @size = 0
     @token_listeners = nil
diff --git a/lib/rdoc/rd/block_parser.rb b/lib/rdoc/rd/block_parser.rb
index eb7d46925b..6f70622c0b 100644
--- a/lib/rdoc/rd/block_parser.rb
+++ b/lib/rdoc/rd/block_parser.rb
@@ -18,8 +18,6 @@ class BlockParser < Racc::Parser
 
 # :stopdoc:
 
-TMPFILE = ["rdtmp", $$, 0]
-
 MARK_TO_LEVEL = {
   '='    => 1,
   '=='   => 2,
@@ -129,15 +127,19 @@ def next_token # :nodoc:
     # non-RD part begin
     when /^=begin\s+(\w+)/
       part = $1
+=begin # not imported to RDoc
       if @in_part # if in non-RD part
         @part_content.push(line)
       else
         @in_part = part if @tree.filter[part] # if filter exists
 #  p "BEGIN_PART: #{@in_part}" # DEBUG
       end
+=end
+      @in_part = part
     # non-RD part end
-    when /^=end/
+    when /^=end(?:$|[\s\0\C-d\C-z])/
       if @in_part # if in non-RD part
+=begin # not imported to RDoc
 #  p "END_PART: #{@in_part}" # DEBUG
         # make Part-in object
         part = RDoc::RD::Part.new(@part_content.join(""), @tree, "r")
@@ -148,20 +150,22 @@ def next_token # :nodoc:
         if @tree.filter[@in_part].mode == :rd # if output is RD formatted
           subtree = parse_subtree(part_out.to_a)
         else # if output is target formatted
-          basename = TMPFILE.join('.')
-          TMPFILE[-1] += 1
-          tmpfile = open(@tree.tmp_dir + "/" + basename + ".#{@in_part}", "w")
-          tmpfile.print(part_out)
-          tmpfile.close
+          basename = Tempfile.create(["rdtmp", ".#{@in_part}"], @tree.tmp_dir) do |tmpfile|
+            tmpfile.print(part_out)
+            File.basename(tmpfile.path)
+          end
           subtree = parse_subtree(["=begin\n", "<<< #{basename}\n", "=end\n"])
         end
         @in_part = nil
         return [:SUBTREE, subtree]
+=end
       end
     else
+=begin # not imported to RDoc
       if @in_part # if in non-RD part
         @part_content.push(line)
       end
+=end
     end
   end
 
diff --git a/lib/rdoc/rdoc.gemspec b/lib/rdoc/rdoc.gemspec
index 525a15fcde..3c96f7deb1 100644
--- a/lib/rdoc/rdoc.gemspec
+++ b/lib/rdoc/rdoc.gemspec
@@ -38,16 +38,12 @@ RDoc includes the +rdoc+ and +ri+ tools for generating and displaying documentat
     "CVE-2013-0256.rdoc",
     "ExampleMarkdown.md",
     "ExampleRDoc.rdoc",
-    "Gemfile",
     "History.rdoc",
     "LEGAL.rdoc",
     "LICENSE.rdoc",
     "README.rdoc",
     "RI.rdoc",
-    "Rakefile",
     "TODO.rdoc",
-    "bin/console",
-    "bin/setup",
     "exe/rdoc",
     "exe/ri",
     "lib/rdoc.rb",
@@ -223,24 +219,12 @@ RDoc includes the +rdoc+ and +ri+ tools for generating and displaying documentat
     "lib/rdoc/top_level.rb",
     "lib/rdoc/version.rb",
     "man/ri.1",
-    "rdoc.gemspec",
   ]
   # files from .gitignore
   s.files << "lib/rdoc/rd/block_parser.rb" << "lib/rdoc/rd/inline_parser.rb" << "lib/rdoc/markdown.rb" << "lib/rdoc/markdown/literals.rb"
 
   s.rdoc_options = ["--main", "README.rdoc"]
-  s.extra_rdoc_files += %w[
-    CVE-2013-0256.rdoc
-    CONTRIBUTING.rdoc
-    ExampleMarkdown.md
-    ExampleRDoc.rdoc
-    History.rdoc
-    LEGAL.rdoc
-    LICENSE.rdoc
-    README.rdoc