1303 files changed, 54462 insertions, 12655 deletions

diff --git a/.appveyor.yml b/.appveyor.yml
index 6803edff9b..05ff204541 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -26,8 +26,9 @@ environment:
     # 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
+      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"
@@ -47,6 +48,7 @@ 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 --x-use-aria2 libffi libyaml readline zlib
     - CALL SET vcvars=%%^VS%VS%COMNTOOLS^%%..\..\VC\vcvarsall.bat
@@ -75,6 +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%
     - >-
@@ -91,7 +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
@@ -102,7 +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
diff --git a/.cirrus.yml b/.cirrus.yml
deleted file mode 100644
index 6c47159921..0000000000
--- a/.cirrus.yml
+++ /dev/null
@@ -1,133 +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 / $CC
-  skip: "changesIncludeOnly('doc/**', '**.{md,rdoc,ronn,[1-8]}', '.document')"
-  arm_container:
-    # We use the arm64 images at https://github.com/ruby/ruby-ci-image/pkgs/container/ruby-ci-image .
-    image: ghcr.io/ruby/ruby-ci-image:$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"
-    - cat "$CIRRUS_ENV"
-  # Arm containers are executed in AWS's EKS, and it's not yet supporting IPv6
-  # See https://github.com/aws/containers-roadmap/issues/835
-  disable_ipv6_script: sudo ./tool/disable_ipv6.sh
-  autogen_script: ./autogen.sh
-  configure_script: >-
-    ./configure -C
-    --enable-debug-env
-    --disable-install-doc
-    --with-ext=-test-/cxxanyargs,+
-    --prefix="$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
-
-# The following is to test YJIT on ARM64 CPUs available on Cirrus CI
-yjit_task:
-  name: Arm64 Graviton2 / $CC YJIT
-  auto_cancellation: $CIRRUS_BRANCH != 'master'
-  skip: "changesIncludeOnly('doc/**', '**.{md,rdoc,ronn,[1-8]}', '.document')"
-  arm_container:
-    # We use the arm64 images at https://github.com/ruby/ruby-ci-image/pkgs/container/ruby-ci-image .
-    image: ghcr.io/ruby/ruby-ci-image:$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
-        configure: --enable-yjit=dev
-        rustup_init: --default-toolchain=1.58.0
-      - CC: gcc-11
-        configure: --enable-yjit
-  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"
-    - echo RUST_BACKTRACE=1 >> "$CIRRUS_ENV"
-    - cat "$CIRRUS_ENV"
-  # 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
-  install_rust_script:
-    - sudo apt-get update -y
-    - sudo apt-get install -y curl
-    - "curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y $rustup_init"
-  autogen_script: ./autogen.sh
-  configure_script: >-
-    source $HOME/.cargo/env && ./configure -C
-    --enable-debug-env
-    --disable-install-doc
-    --with-ext=-test-/cxxanyargs,+
-    --prefix="$RUBY_PREFIX"
-    $configure
-  make_miniruby_script: source $HOME/.cargo/env && make miniruby
-  make_bindgen_script: |
-    if [[ "$CC" = "clang-12" ]]; then
-      source $HOME/.cargo/env && make yjit-bindgen
-    else
-      echo "only running bindgen on clang image"
-    fi
-  boot_miniruby_script: ./miniruby --yjit-call-threshold=1 -e0
-  test_dump_insns_script: ./miniruby --yjit-call-threshold=1 --yjit-dump-insns -e0
-  output_stats_script: ./miniruby --yjit-call-threshold=1 --yjit-stats -e0
-  full_build_script: source $HOME/.cargo/env && make
-  cargo_test_script: source $HOME/.cargo/env && cd yjit && cargo test
-  make_test_script: source $HOME/.cargo/env && make test RUN_OPTS="--yjit-call-threshold=1 --yjit-verify-ctx"
-  make_test_all_script: source $HOME/.cargo/env && make test-all RUN_OPTS="--yjit-call-threshold=1 --yjit-verify-ctx" TESTOPTS="$RUBY_TESTOPTS"
-  make_test_spec_script: source $HOME/.cargo/env && make test-spec RUN_OPTS="--yjit-call-threshold=1 --yjit-verify-ctx"
diff --git a/.document b/.document
index 7c6d9967b1..3a6b0c238c 100644
--- a/.document
+++ b/.document
@@ -18,6 +18,7 @@ gc.rb
 io.rb
 kernel.rb
 marshal.rb
+mjit.rb
 numeric.rb
 nilclass.rb
 pack.rb
@@ -28,6 +29,7 @@ timev.rb
 thread_sync.rb
 trace_point.rb
 warning.rb
+yjit.rb
 
 # the lib/ directory (which has its own .document file)
 lib
diff --git a/.github/auto_request_review.yml b/.github/auto_request_review.yml
deleted file mode 100644
index d058b6ca00..0000000000
--- a/.github/auto_request_review.yml
+++ /dev/null
@@ -1,9 +0,0 @@
-files:
-  'yjit*': [team:yjit]
-  'yjit/**/*': [team:yjit]
-  'doc/yjit/*': [team:yjit]
-  'bootstraptest/test_yjit*': [team:yjit]
-  'test/ruby/test_yjit*': [team:yjit]
-  '.github/workflows/yjit*': [team:yjit]
-options:
-  ignore_draft: true
diff --git a/.github/workflows/auto_request_review.yml b/.github/workflows/auto_request_review.yml
deleted file mode 100644
index f837905fe6..0000000000
--- a/.github/workflows/auto_request_review.yml
+++ /dev/null
@@ -1,19 +0,0 @@
-name: Auto Request Review
-on:
-  pull_request_target:
-    types: [opened, ready_for_review, reopened]
-
-permissions:
-  contents: read
-
-jobs:
-  auto-request-review:
-    name: Auto Request Review
-    runs-on: ubuntu-latest
-    if: ${{ github.repository == 'ruby/ruby' }}
-    steps:
-      - name: Request review based on files changes and/or groups the author belongs to
-        uses: necojackarc/auto-request-review@b5e81876454003a4ccb9b89cb205c67d77d7035b # v0.8.0
-        with:
-          # scope: public_repo
-          token: ${{ secrets.MATZBOT_GITHUB_TOKEN }}
diff --git a/.github/workflows/baseruby.yml b/.github/workflows/baseruby.yml
index 620847597d..ebaafe3bf0 100644
--- a/.github/workflows/baseruby.yml
+++ b/.github/workflows/baseruby.yml
@@ -4,19 +4,24 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
   pull_request:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
@@ -28,7 +33,7 @@ permissions:
 jobs:
   baseruby:
     name: BASERUBY
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
     strategy:
       matrix:
@@ -43,12 +48,12 @@ jobs:
           - ruby-3.1
 
     steps:
-      - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
-      - uses: actions/cache@9b0c1fce7a93df8e3bb8926b0d6e9d89e92f20a7 # v3.0.11
+      - 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@c7079efafd956afb5d823e8999c2506e1053aefa # v1.126.0
+      - uses: ruby/setup-ruby@13e7a03dc3ac6c3798f4570bfead2aed4d96abfb # v1.244.0
         with:
           ruby-version: ${{ matrix.ruby }}
           bundler: none
@@ -60,7 +65,7 @@ jobs:
       - run: make incs
       - run: make all
       - run: make test
-      - uses: ruby/action-slack@b6882ea6ef8f556f9f9af9ec1220d3f1ced74acf # v3.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
diff --git a/.github/workflows/bundled_gems.yml b/.github/workflows/bundled_gems.yml
index 942988c7d8..070c0fa1dd 100644
--- a/.github/workflows/bundled_gems.yml
+++ b/.github/workflows/bundled_gems.yml
@@ -2,10 +2,17 @@ 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'
@@ -34,9 +41,9 @@ jobs:
           echo "GNUMAKEFLAGS=-j$((1 + $(nproc --all)))" >> $GITHUB_ENV
           echo "TODAY=$(date +%F)" >> $GITHUB_ENV
 
-      - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
 
-      - uses: actions/cache@9b0c1fce7a93df8e3bb8926b0d6e9d89e92f20a7 # v3.0.11
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: .downloaded-cache
           key: downloaded-cache-${{ github.sha }}
@@ -81,7 +88,7 @@ jobs:
             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}
@@ -143,3 +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 cf9b5e8b60..79b2916feb 100644
--- a/.github/workflows/check_dependencies.yml
+++ b/.github/workflows/check_dependencies.yml
@@ -3,19 +3,24 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
   pull_request:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
@@ -28,7 +33,7 @@ jobs:
   update-deps:
     strategy:
       matrix:
-        os: [ubuntu-20.04]
+        os: [ubuntu-22.04]
       fail-fast: true
     runs-on: ${{ matrix.os }}
     if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
@@ -41,15 +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@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
-      - uses: actions/cache@9b0c1fce7a93df8e3bb8926b0d6e9d89e92f20a7 # v3.0.11
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: .downloaded-cache
           key: downloaded-cache
@@ -59,7 +63,7 @@ jobs:
       - run: make all golf
       - run: ruby tool/update-deps --fix
       - run: git diff --no-ext-diff --ignore-submodules --exit-code
-      - uses: ruby/action-slack@b6882ea6ef8f556f9f9af9ec1220d3f1ced74acf # v3.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
diff --git a/.github/workflows/check_misc.yml b/.github/workflows/check_misc.yml
deleted file mode 100644
index 2a8cfabefd..0000000000
--- a/.github/workflows/check_misc.yml
+++ /dev/null
@@ -1,122 +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: ${{ startsWith(github.event_name, 'pull') }}
-
-permissions:
-  contents: read
-
-jobs:
-  checks:
-    permissions:
-      contents: write  # for Git to git push
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
-      - name: Check if C-sources are US-ASCII
-        run: |
-          ! grep -r -n '[^	 -~]' -- *.[chy] include internal win32/*.[ch]
-      - name: Check for trailing spaces
-        run: |
-          ! git grep -n '[	 ]$' -- '*.rb' '*.[chy]'
-          ! git grep -n '^[	 ][	 ]*$' -- '*.md'
-      - name: Check for bash specific substitution in configure.ac
-        run: |
-          ! git grep -n '\${[A-Za-z_0-9]*/' -- configure.ac
-      - 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 $header
-          done | grep -F .
-        working-directory: include
-
-      - uses: actions/cache@9b0c1fce7a93df8e3bb8926b0d6e9d89e92f20a7 # v3.0.11
-        with:
-          path: .downloaded-cache
-          key: downloaded-cache-${{ 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: |
-          #!ruby
-          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: |
-          #!ruby
-          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: ${{ github.repository == 'ruby/ruby' && !startsWith(github.event_name, 'pull') && steps.diff.outcome == 'failure' }}
-
-      - uses: ruby/action-slack@b6882ea6ef8f556f9f9af9ec1220d3f1ced74acf # v3.0.0
-        with:
-          payload: |
-            {
-              "ci": "GitHub Actions",
-              "env": "${{ github.workflow }}",
-              "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: ${{ failure() && github.event_name == 'push' }}
diff --git a/.github/workflows/cirrus-notify.yml b/.github/workflows/cirrus-notify.yml
deleted file mode 100644
index 5edba0ae8f..0000000000
--- a/.github/workflows/cirrus-notify.yml
+++ /dev/null
@@ -1,46 +0,0 @@
-on:
-  check_suite:
-    type: ['completed']
-name: Cirrus CI failure notification
-
-permissions:
-  contents: read
-
-jobs:
-  cirrus-notify:
-    name: After Cirrus CI Failure
-    if: >-
-      github.event.check_suite.app.name == 'Cirrus CI'
-      && github.event.check_suite.conclusion != 'success'
-      && github.event.check_suite.conclusion != 'cancelled'
-      && github.event.check_suite.conclusion != 'skipped'
-      && github.event.check_suite.head_branch == 'master'
-    runs-on: ubuntu-latest
-    steps:
-      - uses: octokit/request-action@52ce92ce3185e00e2425f043c3e9509121929aea # v2.x
-        id: get_failed_check_run
-        with:
-          route: GET /repos/${{ github.repository }}/check-suites/${{ github.event.check_suite.id }}/check-runs?status=completed
-          mediaType: '{"previews": ["antiope"]}'
-        env:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-      - name: Dump GitHub context
-        env:
-          GITHUB_CONTEXT: ${{ toJson(github) }}
-        run: echo "$GITHUB_CONTEXT"
-      - name: Dump check_runs
-        env:
-          CHECK_RUNS: ${{ steps.get_failed_check_run.outputs.data }}
-        run: echo "$CHECK_RUNS"
-      - uses: ruby/action-slack@b6882ea6ef8f556f9f9af9ec1220d3f1ced74acf # v3.0.0
-        with:
-          payload: |
-            {
-              "ci": "Cirrus CI",
-              "env": "Cirrus CI",
-              "url": "${{ fromJson(steps.get_failed_check_run.outputs.data).check_runs[0].html_url }}",
-              "commit": "${{ github.event.check_suite.head_commit.id }}",
-              "branch": "${{ github.event.check_suite.head_branch }}"
-            }
-        env:
-          SLACK_WEBHOOK_URL: ${{ secrets.SIMPLER_ALERTS_URL }} # ruby-lang slack: ruby/simpler-alerts-bot
diff --git a/.github/workflows/codeql-analysis.yml b/.github/workflows/codeql-analysis.yml
index 643d6ddf92..8dba76fbe2 100644
--- a/.github/workflows/codeql-analysis.yml
+++ b/.github/workflows/codeql-analysis.yml
@@ -4,19 +4,17 @@ on:
   # push:
   #   paths-ignore:
   #     - 'doc/**'
+  #     - '**/man'
   #     - '**.md'
   #     - '**.rdoc'
   #     - '**/.document'
-  #     - '**.[1-8]'
-  #     - '**.ronn'
   # pull_request:
   #   paths-ignore:
   #     - 'doc/**'
+  #     - '**/man'
   #     - '**.md'
   #     - '**.rdoc'
   #     - '**/.document'
-  #     - '**.[1-8]'
-  #     - '**.ronn'
   schedule:
     - cron: '0 12 * * *'
   workflow_dispatch:
@@ -51,9 +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@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
+      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
 
-    - uses: actions/cache@9b0c1fce7a93df8e3bb8926b0d6e9d89e92f20a7 # v3.0.11
+    - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
       with:
         path: .downloaded-cache
         key: downloaded-cache
@@ -62,15 +60,16 @@ jobs:
       run: sudo rm /usr/lib/ruby/vendor_ruby/rubygems/defaults/operating_system.rb
 
     - name: Initialize CodeQL
-      uses: github/codeql-action/init@b2a92eb56d8cb930006a1c6ed86b0782dd8a4297 # v2.1.35
+      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@b2a92eb56d8cb930006a1c6ed86b0782dd8a4297 # v2.1.35
+      uses: github/codeql-action/autobuild@959cbb7472c4d4ad70cdfe6f4976053fe48ab394 # v2.1.37
 
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@b2a92eb56d8cb930006a1c6ed86b0782dd8a4297 # v2.1.35
+      uses: github/codeql-action/analyze@959cbb7472c4d4ad70cdfe6f4976053fe48ab394 # v2.1.37
diff --git a/.github/workflows/compilers.yml b/.github/workflows/compilers.yml
index b6db2138fd..caf12cc0f4 100644
--- a/.github/workflows/compilers.yml
+++ b/.github/workflows/compilers.yml
@@ -4,19 +4,22 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
   pull_request:
     paths-ignore:
       - 'doc/**'
-      - '**.md'
+      - '**/man'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
@@ -77,27 +80,13 @@ jobs:
           - { 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-6,     env: { default_cc: gcc-6 } }
-          - { name: gcc-5,     env: { default_cc: gcc-5 } }
-          - { name: gcc-4.8,   env: { default_cc: gcc-4.8 } }
-          - name: 'gcc-11 LTO'
-            container: gcc-11
+          - name: 'gcc-13 LTO'
+            container: gcc-13
             env:
-              default_cc: 'gcc-11 -flto=auto -ffat-lto-objects'
+              default_cc: 'gcc-13 -flto=auto -ffat-lto-objects -Werror=lto-type-mismatch'
               optflags: '-O2'
             shared: disable
             # check: true
-          - name: 'gcc-11 annocheck'
-            container: gcc-11
-            env:
-              # Minimal flags to pass the check.
-              default_cc: 'gcc-11 -O2 -fcf-protection -Wa,--generate-missing-build-notes=yes'
-              LDFLAGS: '-Wl,-z,now'
-              # FIXME: Drop skipping options
-              # https://bugs.ruby-lang.org/issues/18061
-              # https://sourceware.org/annobin/annobin.html/Test-pie.html
-              TEST_ANNOCHECK_OPTS: "--skip-pie"
-            check: true
           - { name: clang-16,  env: { default_cc: clang-16 } }
           - { name: clang-15,  env: { default_cc: clang-15 } }
           - { name: clang-14,  env: { default_cc: clang-14 } }
@@ -105,17 +94,15 @@ jobs:
           - { name: clang-12,  env: { default_cc: clang-12 } }
           - { name: clang-11,  env: { default_cc: clang-11 } }
           - { name: clang-10,  env: { default_cc: clang-10 } }
-          - { name: clang-9,   env: { default_cc: clang-9 } }
-          - { name: clang-8,   env: { default_cc: clang-8 } }
-          - { name: clang-7,   env: { default_cc: clang-7 } }
-          - { name: clang-6.0, env: { default_cc: clang-6.0 } }
-          - { name: clang-5.0, env: { default_cc: clang-5.0 } }
-          - { name: clang-4.0, env: { default_cc: clang-4.0 } }
-          - { name: clang-3.9, env: { default_cc: clang-3.9 } }
-          - name: 'clang-14 LTO'
-            container: clang-14
+          # 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-14 -flto=auto'
+              default_cc: 'clang-16 -flto=auto'
               optflags: '-O2'
             shared: disable
             # check: true
@@ -181,7 +168,11 @@ jobs:
 #         - { 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' } }
+          - 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' } }
@@ -234,10 +225,10 @@ jobs:
       - name: setenv
         run: |
           echo "GNUMAKEFLAGS=-sj$((1 + $(nproc --all)))" >> $GITHUB_ENV
-      - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           path: src
-      - uses: actions/cache@9b0c1fce7a93df8e3bb8926b0d6e9d89e92f20a7 # v3.0.11
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: src/.downloaded-cache
           key: downloaded-cache
@@ -271,7 +262,7 @@ jobs:
       - run: make test-annocheck
         if: ${{ matrix.entry.check && endsWith(matrix.entry.name, 'annocheck') }}
 
-      - uses: ruby/action-slack@b6882ea6ef8f556f9f9af9ec1220d3f1ced74acf # v3.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
diff --git a/.github/workflows/macos.yml b/.github/workflows/macos.yml
index 92ea46388e..d8dc58b119 100644
--- a/.github/workflows/macos.yml
+++ b/.github/workflows/macos.yml
@@ -3,19 +3,24 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
   pull_request:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
@@ -30,8 +35,9 @@ jobs:
       matrix:
         test_task: ["check"] # "test-bundler-parallel", "test-bundled-gems"
         os:
-          - macos-11
-          - macos-12
+          - macos-13
+          - macos-14
+          - macos-15
       fail-fast: false
     env:
       GITPULLOPTIONS: --no-tags origin ${{github.ref}}
@@ -44,22 +50,21 @@ jobs:
         run: |
           git config --global advice.detachedHead 0
           git config --global init.defaultBranch garbage
-      - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           path: src
-      - uses: actions/cache@9b0c1fce7a93df8e3bb8926b0d6e9d89e92f20a7 # v3.0.11
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: src/.downloaded-cache
           key: downloaded-cache
       - name: Install libraries
         run: |
-          brew upgrade
           brew install gmp libffi openssl@1.1 zlib autoconf automake libtool readline bison
         working-directory: src
       - name: Set ENV
         run: |
           echo "MAKEFLAGS=-j$((1 + $(sysctl -n hw.activecpu)))" >> $GITHUB_ENV
-          echo "PATH="/usr/local/opt/bison/bin:$PATH"" >> $GITHUB_ENV
+          echo "PATH="/usr/local/opt/bison/bin:/opt/homebrew/opt/bison/bin:$PATH"" >> $GITHUB_ENV
       - run: ./autogen.sh
         working-directory: src
       - name: Run configure
@@ -89,7 +94,7 @@ jobs:
           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@b6882ea6ef8f556f9f9af9ec1220d3f1ced74acf # v3.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
diff --git a/.github/workflows/mingw.yml b/.github/workflows/mingw.yml
index c5c24d9c17..0df917d3d8 100644
--- a/.github/workflows/mingw.yml
+++ b/.github/workflows/mingw.yml
@@ -3,19 +3,24 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
   pull_request:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
@@ -60,15 +65,15 @@ jobs:
           git config --global core.eol lf
           git config --global advice.detachedHead 0
           git config --global init.defaultBranch garbage
-      - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           path: src
-      - uses: actions/cache@9b0c1fce7a93df8e3bb8926b0d6e9d89e92f20a7 # v3.0.11
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: src/.downloaded-cache
           key: downloaded-cache
       - name: Set up Ruby & MSYS2
-        uses: ruby/setup-ruby@c7079efafd956afb5d823e8999c2506e1053aefa # v1.126.0
+        uses: ruby/setup-ruby@13e7a03dc3ac6c3798f4570bfead2aed4d96abfb # v1.244.0
         with:
           ruby-version: ${{ matrix.base_ruby }}
       - name: set env
@@ -154,7 +159,7 @@ jobs:
           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: ruby/action-slack@b6882ea6ef8f556f9f9af9ec1220d3f1ced74acf # v3.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
diff --git a/.github/workflows/mjit-bindgen.yml b/.github/workflows/mjit-bindgen.yml
index f6d3ff793a..26f8a1b2aa 100644
--- a/.github/workflows/mjit-bindgen.yml
+++ b/.github/workflows/mjit-bindgen.yml
@@ -3,19 +3,24 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
   pull_request:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
@@ -31,7 +36,7 @@ jobs:
         include:
           - task: mjit-bindgen
       fail-fast: false
-    runs-on: ubuntu-20.04
+    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
@@ -47,21 +52,21 @@ jobs:
           build-essential \
           libssl-dev libyaml-dev libreadline6-dev \
           zlib1g-dev libncurses5-dev libffi-dev \
-          libclang1-10 \
+          libclang1-14 \
           bison autoconf
           sudo apt-get install -q -y pkg-config || :
       - name: Set up Ruby
-        uses: ruby/setup-ruby@c7079efafd956afb5d823e8999c2506e1053aefa # v1.126.0
+        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@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           path: src
-      - uses: actions/cache@9b0c1fce7a93df8e3bb8926b0d6e9d89e92f20a7 # v3.0.11
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: src/.downloaded-cache
           key: downloaded-cache
@@ -80,7 +85,7 @@ jobs:
       - run: make ${{ matrix.task }}
       - run: git diff --exit-code
         working-directory: src
-      - uses: ruby/action-slack@b6882ea6ef8f556f9f9af9ec1220d3f1ced74acf # v3.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
diff --git a/.github/workflows/mjit.yml b/.github/workflows/mjit.yml
index f2fd9ad076..6f7181489a 100644
--- a/.github/workflows/mjit.yml
+++ b/.github/workflows/mjit.yml
@@ -3,12 +3,20 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  pull_request:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
       - '**.[1-8]'
       - '**.ronn'
-  pull_request:
+  merge_group:
     paths-ignore:
       - 'doc/**'
       - '**.md'
@@ -49,10 +57,10 @@ jobs:
         run: |
           git config --global advice.detachedHead 0
           git config --global init.defaultBranch garbage
-      - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           path: src
-      - uses: actions/cache@9b0c1fce7a93df8e3bb8926b0d6e9d89e92f20a7 # v3.0.11
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: src/.downloaded-cache
           key: downloaded-cache
@@ -71,10 +79,9 @@ jobs:
       - run: make incs
       - run: make
       - run: sudo make -s install
-      - run: sudo apt-get install gdb # used by test / test-all failure
       - name: Run test
         run: |
-          ulimit -c unlimited
+          unset GNUMAKEFLAGS
           make -s test RUN_OPTS="$RUN_OPTS"
         timeout-minutes: 60
       # - name: Run test-all
@@ -84,10 +91,10 @@ jobs:
       #   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: ruby/action-slack@b6882ea6ef8f556f9f9af9ec1220d3f1ced74acf # v3.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
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
index 8236a2cd1a..c12a95362d 100644
--- a/.github/workflows/scorecards.yml
+++ b/.github/workflows/scorecards.yml
@@ -32,12 +32,12 @@ jobs:
 
     steps:
       - name: "Checkout code"
-        uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           persist-credentials: false
 
       - name: "Run analysis"
-        uses: ossf/scorecard-action@99c53751e09b9529366343771cc321ec74e9bd3d # v2.0.6
+        uses: ossf/scorecard-action@ea651e62978af7915d09fe2e282747c798bf2dab # v2.4.1
         with:
           results_file: results.sarif
           results_format: sarif
@@ -59,7 +59,7 @@ jobs:
       # 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@83fd05a356d7e2593de66fc9913b3002723633cb # v3.1.1
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
         with:
           name: SARIF file
           path: results.sarif
@@ -67,6 +67,6 @@ jobs:
 
       # Upload the results to GitHub's code scanning dashboard.
       - name: "Upload to code-scanning"
-        uses: github/codeql-action/upload-sarif@b2a92eb56d8cb930006a1c6ed86b0782dd8a4297 # v2.1.27
+        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 2936e892a3..4521195a2b 100644
--- a/.github/workflows/spec_guards.yml
+++ b/.github/workflows/spec_guards.yml
@@ -6,9 +6,10 @@ on:
       - 'spec/**'
       - '!spec/*.md'
   pull_request:
-    paths-ignore:
+    paths:
       - 'spec/**'
       - '!spec/*.md'
+  merge_group:
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
@@ -20,28 +21,42 @@ permissions:
 jobs:
   rubyspec:
     name: Rubyspec
-    runs-on: ubuntu-20.04
-    if: ${{ !contains(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@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
-      - uses: ruby/setup-ruby@c7079efafd956afb5d823e8999c2506e1053aefa # v1.126.0
+      - 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
         env:
           CHECK_LEAKS: true
-      - uses: ruby/action-slack@b6882ea6ef8f556f9f9af9ec1220d3f1ced74acf # v3.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
@@ -53,4 +68,4 @@ jobs:
             }
         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 f5b259c84a..4fbca1170e 100644
--- a/.github/workflows/ubuntu.yml
+++ b/.github/workflows/ubuntu.yml
@@ -3,19 +3,24 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
   pull_request:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
@@ -41,7 +46,6 @@ jobs:
           - test_task: check
             configure: "--enable-shared --enable-load-relative"
           - test_task: test-all TESTS=--repeat-count=2
-          - test_task: test-syntax-suggest
           - test_task: test-bundler-parallel
           - test_task: test-bundled-gems
       fail-fast: false
@@ -49,7 +53,7 @@ jobs:
       GITPULLOPTIONS: --no-tags origin ${{github.ref}}
       RUBY_DEBUG: ci
       SETARCH: ${{ matrix.arch && format('setarch {0}', matrix.arch) }}
-    runs-on: ubuntu-20.04
+    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
@@ -75,10 +79,10 @@ jobs:
         run: |
           git config --global advice.detachedHead 0
           git config --global init.defaultBranch garbage
-      - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           path: src
-      - uses: actions/cache@9b0c1fce7a93df8e3bb8926b0d6e9d89e92f20a7 # v3.0.11
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: src/.downloaded-cache
           key: downloaded-cache
@@ -123,7 +127,7 @@ jobs:
           TESTS: ${{ matrix.skipped_tests }}
         if: ${{ matrix.test_task == 'check' && matrix.skipped_tests != '' }}
         continue-on-error: ${{ matrix.continue-on-skipped_tests || false }}
-      - uses: ruby/action-slack@b6882ea6ef8f556f9f9af9ec1220d3f1ced74acf # v3.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
diff --git a/.github/workflows/wasm.yml b/.github/workflows/wasm.yml
index 3114078256..27920b5821 100644
--- a/.github/workflows/wasm.yml
+++ b/.github/workflows/wasm.yml
@@ -3,19 +3,24 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
   pull_request:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
@@ -45,7 +50,7 @@ jobs:
       WASI_SDK_VERSION_MINOR: 0
       BINARYEN_VERSION: 109
       WASMTIME_VERSION: v0.33.0
-    runs-on: ubuntu-20.04
+    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
@@ -54,7 +59,7 @@ jobs:
         run: |
           git config --global advice.detachedHead 0
           git config --global init.defaultBranch garbage
-      - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           path: src
       - name: Install libraries
@@ -86,6 +91,18 @@ jobs:
           echo "WASI_SDK_PATH=/opt/wasi-sdk" >> $GITHUB_ENV
       - run: ./autogen.sh
         working-directory: src
+
+      - uses: ruby/setup-ruby@13e7a03dc3ac6c3798f4570bfead2aed4d96abfb # v1.244.0
+        with:
+          ruby-version: '3.0'
+          bundler: none
+
+      - name: Download config.guess with wasi version
+        run: |
+          rm tool/config.guess tool/config.sub
+          ruby tool/downloader.rb -d tool -e gnu config.guess config.sub
+        working-directory: src
+
       - name: Run configure
         run: |
           ../src/configure \
@@ -110,6 +127,20 @@ jobs:
           ruby ./bootstraptest/runner.rb --ruby="$(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 674f627ef9..c2bd4881c2 100644
--- a/.github/workflows/windows.yml
+++ b/.github/workflows/windows.yml
@@ -3,19 +3,24 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
   pull_request:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
@@ -29,85 +34,68 @@ jobs:
     strategy:
       matrix:
         include:
-          - vs: 2019
           - vs: 2022
+            vcvers: -vcvars_ver=14.2
       fail-fast: false
-    runs-on: windows-${{ matrix.vs < 2022 && '2019' || matrix.vs }}
+    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@d40200dc2db4c351366b048a9565ad82919e1c24 # 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@9b0c1fce7a93df8e3bb8926b0d6e9d89e92f20a7 # v3.0.11
-        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@9b0c1fce7a93df8e3bb8926b0d6e9d89e92f20a7 # v3.0.11
+      - 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@9b0c1fce7a93df8e3bb8926b0d6e9d89e92f20a7 # v3.0.11
-        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 }}-
-            ${{ runner.os }}-chocolatey-
-      - name: Install libraries with chocolatey
-        run: |
-          # Using Choco-Install for retries, but it doesn't detect failures properly
-          # if you pass multiple package names in a single command.
-          Choco-Install -PackageName winflexbison3
-        shell: pwsh
+        shell:
+          pwsh
       - name: git config
         run: |
           git config --global core.autocrlf false
           git config --global core.eol lf
           git config --global advice.detachedHead 0
           git config --global init.defaultBranch garbage
-      - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           path: src
-      - uses: actions/cache@9b0c1fce7a93df8e3bb8926b0d6e9d89e92f20a7 # v3.0.11
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: src/.downloaded-cache
           key: downloaded-cache
       - name: setup env
         # %TEMP% is inconsistent with %TMP% and test-all expects they are consistent.
         # https://github.com/actions/virtual-environments/issues/712#issuecomment-613004302
+        # msys2/setup-msys2 installs MSYS2 to D:/a/_temp/msys64/usr/bin
         run: |
-          set VS=${{ 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% ${{ matrix.vcvers || ''}}
           set TMP=%USERPROFILE%\AppData\Local\Temp
           set TEMP=%USERPROFILE%\AppData\Local\Temp
           set /a TEST_JOBS=(15 * %NUMBER_OF_PROCESSORS% / 10) > nul
@@ -132,7 +120,7 @@ jobs:
       - run: nmake extract-extlibs
       - run: nmake
         env:
-          YACC: win_bison
+          YACC: bison.exe
       - run: nmake test
         timeout-minutes: 5
       - run: nmake test-spec
@@ -141,7 +129,7 @@ jobs:
         env:
           RUBY_TESTOPTS: -j${{env.TEST_JOBS}} --job-status=normal
         timeout-minutes: 60
-      - uses: ruby/action-slack@b6882ea6ef8f556f9f9af9ec1220d3f1ced74acf # v3.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
diff --git a/.github/workflows/yjit-ubuntu.yml b/.github/workflows/yjit-ubuntu.yml
index 2895afd027..0b7b9046e9 100644
--- a/.github/workflows/yjit-ubuntu.yml
+++ b/.github/workflows/yjit-ubuntu.yml
@@ -3,19 +3,24 @@ on:
   push:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
   pull_request:
     paths-ignore:
       - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
       - '**.md'
       - '**.rdoc'
       - '**/.document'
-      - '**.[1-8]'
-      - '**.ronn'
 
 concurrency:
   group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
@@ -28,9 +33,9 @@ jobs:
   cargo:
     name: Rust cargo test
     # GitHub Action's image seems to already contain a Rust 1.58.0.
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     steps:
-      - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
+      - 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
@@ -47,8 +52,10 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - test_task: "check-yjit-bindings"
-            configure: "--with-gcc=clang-12 --enable-yjit=dev"
+          - 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
@@ -78,7 +85,7 @@ jobs:
       YJIT_BENCH_OPTS: ${{ matrix.yjit_bench_opts }}
       RUBY_DEBUG: ci
       BUNDLE_JOBS: 8 # for yjit-bench
-    runs-on: ubuntu-20.04
+    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
@@ -95,10 +102,10 @@ jobs:
         run: |
           git config --global advice.detachedHead 0
           git config --global init.defaultBranch garbage
-      - uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           path: src
-      - uses: actions/cache@9b0c1fce7a93df8e3bb8926b0d6e9d89e92f20a7 # v3.0.11
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: src/.downloaded-cache
           key: downloaded-cache
@@ -136,6 +143,7 @@ jobs:
           RUBY_TESTOPTS: "-q --tty=no"
           TEST_BUNDLED_GEMS_ALLOW_FAILURES: ""
           PRECHECK_BUNDLED_GEMS: "no"
+          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}"
@@ -143,7 +151,7 @@ jobs:
           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@b6882ea6ef8f556f9f9af9ec1220d3f1ced74acf # v3.0.0
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
         with:
           payload: |
             {
diff --git a/.gitignore b/.gitignore
index 068b62c095..99d32a1825 100644
--- a/.gitignore
+++ b/.gitignore
@@ -14,6 +14,7 @@
 *.inc
 *.log
 *.o
+*.o.tmp
 *.obj
 *.old
 *.orig
@@ -237,7 +238,7 @@ lcov*.info
 
 # MJIT
 /include/ruby-*/*/rb_mjit_min_header-*.h
-/lib/mjit/instruction.rb
+/lib/ruby_vm/mjit/instruction.rb
 /mjit_config.h
 /rb_mjit_header.h
 
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index 665feba914..0000000000
--- a/.travis.yml
+++ /dev/null
@@ -1,235 +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 $travis_apt_get_options install
-        ccache
-        crossbuild-essential-armhf
-        libc6:armhf
-        libstdc++-10-dev:armhf
-        libffi-dev:armhf
-        libncurses-dev:armhf
-        libncursesw5-dev:armhf
-        libreadline-dev:armhf
-        libssl-dev:armhf
-        libyaml-dev:armhf
-        linux-libc-dev:armhf
-        zlib1g-dev:armhf
-
-matrix:
-  include:
-    # Build every commit (Allowed Failures):
-    - <<: *arm32-linux
-    # Comment out as the 2nd arm64 pipeline is unstable.
-    # - <<: *arm64-linux
-    - <<: *ppc64le-linux
-    - <<: *s390x-linux
-  allow_failures:
-    # We see multiple errors indicating errors on the Travis environment itself in a short while:
-    # https://app.travis-ci.com/github/ruby/ruby/jobs/544382885
-    # https://app.travis-ci.com/github/ruby/ruby/jobs/544361370
-    # It's not a fault of Ruby's arm32 support but just Travis arm32 seems unsable.
-    - name: arm32-linux
-    # - name: arm64-linux
-    # We see "Some worker was crashed." in about 40% of recent ppc64le-linux jobs
-    # e.g. https://app.travis-ci.com/github/ruby/ruby/jobs/530959548
-    - name: ppc64le-linux
-    # Tentatively disable, because often hungs up **after** all tests
-    # have finished successfully and saving caches.
-    - name: s390x-linux
-  fast_finish: true
-
-before_script:
-  - . tool/ci_functions.sh
-  - |-
-    if [ -n "${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 $JOBS srcs
-  - rm -f config.status Makefile rbconfig.rb .rbconfig.time
-  - |-
-    if [ -d ~/config_2nd ]; then
-      cp -pr ~/config_2nd build
-    else
-      mkdir build
-    fi
-  - mkdir config_1st config_2nd gems/src
-  - chmod -R a-w .
-  - chmod -R u+w build config_1st config_2nd gems/src
-  - cd build
-  - |-
-    case "$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/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 2e83096b60..f6c3c6fc97 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -90,14 +90,6 @@ Note that each entry is kept to a minimum, see links for details.
     foo(k: 1)
     ```
 
-* `eval` and related methods are able to generate code coverage. Enabled using
-  `Coverage.setup(:all)` or `Coverge.setup(eval: true)`. [[Feature #19008]]
-
-* `Coverage.supported?(mode)` enables detection of what coverage modes are
-  supported. [[Feature #19026]]
-
-## Command line options
-
 ## Core classes updates
 
 Note: We're only listing outstanding class updates.
@@ -111,8 +103,8 @@ Note: We're only listing outstanding class updates.
       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
+        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
@@ -159,11 +151,8 @@ Note: We're only listing outstanding class updates.
         STDIN.read # => Blocking operation timed out! (IO::TimeoutError)
         ```
 
-* UNIXSocket
-
-    * Add support for UNIXSocket on Windows. Emulate anonymous sockets. Add
-      support for File.socket? and File::Stat#socket? where possible.
-      [[Feature #19135]]
+    * Introduce `IO.new(..., path:)` and promote `File#path` to `IO#path`.
+      [[Feature #19036]]
 
 * Class
 
@@ -187,6 +176,15 @@ Note: We're only listing outstanding class updates.
       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]]
@@ -194,6 +192,8 @@ Note: We're only listing outstanding class updates.
       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
 
@@ -243,6 +243,13 @@ Note: We're only listing outstanding class updates.
 
 * 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.
@@ -262,7 +269,7 @@ Note: We're only listing outstanding class updates.
 
         1. SyntaxError is suppressed
         2. AST is returned for invalid input
-        3. `end` is complemented when a parser reachs to the end of input but `end` is insufficient
+        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
@@ -313,17 +320,6 @@ Note: We're only listing outstanding class updates.
     * 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.
 
-* 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`
-
 * String
 
     * String#byteindex and String#byterindex have been added. [[Feature #13110]]
@@ -337,24 +333,35 @@ Note: We're only listing outstanding class updates.
     * A Struct class can also be initialized with keyword arguments
       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.each_caller_location is added. [[Feature #16663]]
 
 * Thread::Queue
 
-    * Thread::Queue.pop(timeout: sec) is added. [[Feature #18774]]
+    * 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]]
+    * 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]]
 
@@ -363,8 +370,8 @@ Note: We're only listing outstanding class updates.
     * 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
 
@@ -377,10 +384,52 @@ Note: We're only listing outstanding class updates.
       `"#<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
 
+* 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
@@ -388,84 +437,140 @@ Note: We're only listing outstanding class updates.
     * 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 3.4.0.dev
+    * RubyGems 3.4.1
+    * abbrev 0.1.1
     * benchmark 0.2.1
     * bigdecimal 3.1.3
-    * bundler 2.4.0.dev
+    * bundler 2.4.1
     * cgi 0.3.6
-    * date 3.3.0
+    * csv 3.2.6
+    * date 3.3.3
     * delegate 0.3.0
-    * did_you_mean 1.6.2
+    * 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 1.4.1
+    * 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 0.5.11
+    * io-console 0.6.0
     * io-nonblock 0.2.0
-    * io-wait 0.3.0.pre
+    * io-wait 0.3.0
     * ipaddr 1.2.5
-    * irb 1.5.1
-    * json 2.6.2
-    * logger 1.5.2
+    * irb 1.6.2
+    * json 2.6.3
+    * logger 1.5.3
     * mutex_m 0.1.2
-    * net-http 0.3.1
-    * net-protocol 0.2.0
+    * net-http 0.4.0
+    * net-protocol 0.2.1
     * nkf 0.1.2
     * open-uri 0.3.0
-    * openssl 3.1.0.pre
-    * optparse 0.3.0
+    * open3 0.1.2
+    * openssl 3.1.0
+    * optparse 0.3.1
     * ostruct 0.5.5
     * pathname 0.2.1
     * pp 0.4.0
     * pstore 0.1.2
     * psych 5.0.1
-    * racc 1.6.1
+    * racc 1.6.2
     * rdoc 6.5.0
-    * reline 0.3.1
+    * readline-ext 0.1.5
+    * reline 0.3.2
     * resolv 0.2.2
-    * securerandom 0.2.1
+    * resolv-replace 0.1.1
+    * securerandom 0.2.2
     * set 1.0.3
-    * stringio 3.0.3
-    * syntax_suggest 1.0.1
+    * 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.
 
     * minitest 5.16.3
-    * power_assert 2.0.2
-    * test-unit 3.5.5
+    * power_assert 2.0.3
+    * test-unit 3.5.7
     * net-ftp 0.2.0
-    * net-imap 0.3.1
+    * net-imap 0.3.4
     * net-pop 0.1.2
     * net-smtp 0.3.3
-    * rbs 2.8.1
+    * rbs 2.8.2
     * typeprof 0.21.3
-    * debug 1.7.0
+    * 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.
 
-*   The following default gems are now 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
 
@@ -491,10 +596,10 @@ The following deprecated methods are removed.
   `UnboundMethod#public?`, `UnboundMethod#private?`, `UnboundMethod#protected?`
   [[Bug #18729]] [[Bug #18751]] [[Bug #18435]]
 
-### Source code incompatiblity of extension libraries [[Bug #19100]]
+### Source code incompatibility of extension libraries
 
 * Extension libraries provide PRNG, subclasses of Random, need updates.
-  See [PRNG update] below for more information.
+  See [PRNG update] below for more information. [[Bug #19100]]
 
 ### Error printer
 
@@ -504,9 +609,9 @@ The following deprecated methods are removed.
 ### 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 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]]
+  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
 
@@ -530,6 +635,10 @@ The following deprecated methods are removed.
 
     [[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
@@ -538,9 +647,9 @@ The following APIs are updated.
 
 * PRNG update
 
-    `rb_random_interface_t` updated and versioned.
-    Extension libraries which use this interface and built for older versions.
-    Also `init_int32` function needs to be defined.
+    `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
 
@@ -552,6 +661,7 @@ The following APIs are updated.
     * `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
 
@@ -570,11 +680,25 @@ The following deprecated APIs are removed.
   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]]
@@ -594,12 +718,12 @@ The following deprecated APIs are removed.
     * 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 128 (MiB).
+* The default `--yjit-exec-mem-size` is changed to 64 (MiB).
 * The default `--yjit-call-threshold` is changed to 30.
 
 ### MJIT
 
-* The MJIT compiler is re-implemented in Ruby as a standard library `mjit`.
+* 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.
@@ -607,67 +731,90 @@ The following deprecated APIs are removed.
 * 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
-[Feature #17837]: https://bugs.ruby-lang.org/issues/17837
-[Feature #17881]: https://bugs.ruby-lang.org/issues/17881
-[Feature #18159]: https://bugs.ruby-lang.org/issues/18159
-[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 #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 #18824]: https://bugs.ruby-lang.org/issues/18824
-[Feature #18832]: https://bugs.ruby-lang.org/issues/#18832
-[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 #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 #19100]:     https://bugs.ruby-lang.org/issues/19100
-[Feature #19135]: https://bugs.ruby-lang.org/issues/19135
-[Feature #19138]: https://bugs.ruby-lang.org/issues/19138
+[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とは
 
diff --git a/README.md b/README.md
index 35ef2d9e89..c445448c71 100644
--- a/README.md
+++ b/README.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)
 
 # What is Ruby?
 
diff --git a/addr2line.c b/addr2line.c
index 0d45ec9414..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;
@@ -976,6 +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
@@ -1020,10 +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;
 
@@ -1031,6 +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;
@@ -1077,19 +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);
@@ -1141,13 +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:
@@ -1189,11 +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));
@@ -1208,8 +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));
@@ -1227,28 +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;
@@ -1376,6 +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;
@@ -1386,24 +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;
     }
@@ -1425,7 +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) {
@@ -1440,8 +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;
@@ -1551,6 +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;
     }
@@ -1583,16 +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;
@@ -1646,6 +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 = {};
@@ -1672,7 +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;
@@ -1680,7 +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;
@@ -1697,9 +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));
@@ -1718,6 +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)
@@ -1846,8 +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++) {
@@ -2103,8 +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) {
@@ -2302,6 +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;
diff --git a/array.c b/array.c
index cba1ed376a..b76e9a64a3 100644
--- a/array.c
+++ b/array.c
@@ -226,8 +226,15 @@ ary_embeddable_p(long capa)
 bool
 rb_ary_embeddable_p(VALUE ary)
 {
-    // if the array is shared or a shared root then it's not moveable
-    return !(ARY_SHARED_P(ary) || ARY_SHARED_ROOT_P(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
@@ -242,7 +249,7 @@ rb_ary_size_as_embedded(VALUE ary)
         real_size = ary_embed_size(ARY_HEAP_CAPA(ary));
     }
     else {
-        real_size = sizeof(struct RString);
+        real_size = sizeof(struct RArray);
     }
     return real_size;
 }
@@ -3729,8 +3736,8 @@ rb_ary_bsearch_index(VALUE ary)
             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;
+              case 1: smaller = 0; break;
+              case -1: smaller = 1;
             }
         }
         else {
@@ -8732,7 +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 bf3781d820..adb7287ed3 100644
--- a/ast.c
+++ b/ast.c
@@ -202,6 +202,11 @@ static VALUE
 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;
diff --git a/ast.rb b/ast.rb
index 2b803461ed..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>
+  #
+  #  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>
+  #
+  #   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_.
   #
@@ -63,6 +91,8 @@ module RubyVM::AbstractSyntaxTree
   #
   #     RubyVM::AbstractSyntaxTree.of(method(:hello))
   #     # => #<RubyVM::AbstractSyntaxTree::Node:SCOPE@1:0-3:3>
+  #
+  #   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
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/bignum.c b/bignum.c
index 4f8349dd17..cb2c3b6f07 100644
--- a/bignum.c
+++ b/bignum.c
@@ -4184,7 +4184,6 @@ rb_int_parse_cstr(const char *str, ssize_t len, char **endp, size_t *ndigits,
         }
         if (!c || ISSPACE(c)) --str;
         if (end) len = end - str;
-        ASSERT_LEN();
     }
     c = *str;
     c = conv_digit(c);
@@ -4587,11 +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);
diff --git a/bootstraptest/test_ractor.rb b/bootstraptest/test_ractor.rb
index 70bbaf5434..67e66b03ee 100644
--- a/bootstraptest/test_ractor.rb
+++ b/bootstraptest/test_ractor.rb
@@ -480,7 +480,6 @@ assert_equal 'ok', %q{
 }
 
 # multiple Ractors can receive (wait) from one Ractor
-yjit_enabled = ENV.key?('RUBY_YJIT_ENABLE') || ENV.fetch('RUN_OPTS', '').include?('yjit')
 assert_equal '[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]', %q{
   pipe = Ractor.new do
     loop do
@@ -503,7 +502,7 @@ assert_equal '[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]', %q{
     rs.delete r
     n
   }.sort
-} unless yjit_enabled # flaky with YJIT https://github.com/ruby/ruby/actions/runs/3603398545/jobs/6071549328#step:18:33
+} 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{
@@ -1474,7 +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
@@ -1483,7 +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}")
   }
 }
@@ -1543,7 +1542,7 @@ assert_equal "ok", %q{
 
   1_000.times { idle_worker, tmp_reporter = Ractor.select(*workers) }
   "ok"
-} unless yjit_enabled # flaky with YJIT https://github.com/ruby/ruby/actions/runs/3575374374/jobs/6011846425
+}
 
 assert_equal "ok", %q{
   def foo(*); ->{ super }; end
diff --git a/bootstraptest/test_yjit.rb b/bootstraptest/test_yjit.rb
index 349417595f..5c655b8f25 100644
--- a/bootstraptest/test_yjit.rb
+++ b/bootstraptest/test_yjit.rb
@@ -1,3 +1,33 @@
+# 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)
@@ -221,6 +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
@@ -1141,6 +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
@@ -2173,7 +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{
@@ -2255,7 +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{
@@ -2270,7 +2334,7 @@ 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{
@@ -3456,3 +3520,11 @@ assert_equal 'ok', %q{
 
   cw(4)
 }
+
+assert_normal_exit %{
+  class Bug20997
+    def foo(&) = self.class.name(&)
+
+    new.foo
+  end
+}
diff --git a/class.c b/class.c
index 87ebabef32..cf0b7b821f 100644
--- a/class.c
+++ b/class.c
@@ -404,6 +404,30 @@ class_init_copy_check(VALUE clone, VALUE orig)
     }
 }
 
+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)
 {
@@ -411,6 +435,17 @@ copy_tables(VALUE clone, VALUE orig)
         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 (!RB_TYPE_P(clone, T_ICLASS)) {
         st_data_t id;
@@ -923,7 +958,7 @@ 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;
 
@@ -940,8 +975,6 @@ rb_define_class_id_under(VALUE outer, ID id, VALUE super)
                      " (%"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);
 
         return klass;
     }
@@ -953,12 +986,19 @@ rb_define_class_id_under(VALUE outer, ID id, VALUE 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);
@@ -1105,8 +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. */
@@ -1173,7 +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;
@@ -1237,7 +1277,6 @@ do_include_modules_at(const VALUE klass, VALUE c, VALUE module, int search_super
         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_hidden_new(2);
             VALUE origin[2] = {iclass, RCLASS_ORIGIN(module)};
@@ -1248,14 +1287,11 @@ 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 (BUILTIN_TYPE(klass) == T_MODULE && FL_TEST(klass, RMODULE_IS_REFINEMENT)) {
             VALUE refined_class =
@@ -1572,6 +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
@@ -2148,7 +2205,7 @@ 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 &&
+        if (klass && // no class when hidden from ObjectSpace
             FL_TEST(klass, (FL_SINGLETON|FL_FREEZE)) == FL_SINGLETON) {
             OBJ_FREEZE_RAW(klass);
         }
diff --git a/common.mk b/common.mk
index 3c89be7f3f..126053c9c8 100644
--- a/common.mk
+++ b/common.mk
@@ -43,7 +43,7 @@ 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 =
@@ -224,6 +224,7 @@ MAKE_LINK = $(MINIRUBY) -rfileutils -e "include FileUtils::Verbose" \
 YJIT_RUSTC_ARGS = --crate-name=yjit \
 	--crate-type=staticlib \
 	--edition=2021 \
+	-g \
 	-C opt-level=3 \
 	-C overflow-checks=on \
 	'--out-dir=$(CARGO_TARGET_DIR)/release/' \
@@ -234,9 +235,9 @@ all: $(SHOWFLAGS) main docs
 main: $(SHOWFLAGS) exts $(ENCSTATIC:static=lib)encs
 	@$(NULLCMD)
 
-main: $(srcdir)/lib/mjit/instruction.rb
-srcs: $(srcdir)/lib/mjit/instruction.rb
-$(srcdir)/lib/mjit/instruction.rb: $(tooldir)/insns2vm.rb $(tooldir)/ruby_vm/views/lib/mjit/instruction.rb.erb $(srcdir)/insns.def
+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) $@
 
@@ -639,7 +640,7 @@ clean-local:: clean-runnable
 	$(Q)$(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)$(RMALL) yjit/target
-	-$(Q) $(RMDIR) enc/jis enc/trans enc $(COROUTINE_H:/Context.h=) coroutine 2> $(NULL) || $(NULLCMD)
+	-$(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) || $(NULLCMD)
@@ -765,7 +766,7 @@ clean-spec: PHONY
 	-$(Q) $(RMDIRS) $(RUBYSPEC_CAPIEXT) 2> $(NULL) || $(NULLCMD)
 	-$(Q) $(RMALL) rubyspec_temp
 
-check: main $(DOT_WAIT) test $(DOT_WAIT) test-tool $(DOT_WAIT) test-all $(DOT_WAIT) 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)" && \
@@ -789,10 +790,11 @@ $(arch:noarch=ignore)-fake.rb: $(srcdir)/template/fake.rb.in $(tooldir)/generic_
 	$(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
-	touch $@
+	$(Q) exit > $@
 
 btest: $(TEST_RUNNABLE)-btest
 no-btest: PHONY
@@ -901,6 +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)
@@ -1220,7 +1224,7 @@ $(srcdir)/revision.h$(no_baseruby:no=~disabled~): $(REVISION_H)
 $(REVISION_H)$(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) touch $@
+	$(Q) exit > $@
 
 $(srcdir)/ext/ripper/ripper.c: $(srcdir)/ext/ripper/tools/preproc.rb $(srcdir)/parse.y $(srcdir)/defs/id.def $(srcdir)/ext/ripper/depend
 	$(ECHO) generating $@
@@ -1356,7 +1360,7 @@ after-update:: extract-gems
 
 update-src::
 	$(Q) $(RM) $(REVISION_H) revision.h "$(srcdir)/$(REVISION_H)" "$(srcdir)/revision.h"
-	$(Q) touch "$(srcdir)/revision.h"
+	$(Q) exit > "$(srcdir)/revision.h"
 
 update-remote:: update-src update-download
 update-download:: $(ALWAYS_UPDATE_UNICODE:yes=update-unicode)
@@ -1372,7 +1376,6 @@ update-config_files: PHONY
 
 refresh-gems: update-bundled_gems prepare-gems
 prepare-gems: $(HAVE_BASERUBY:yes=update-gems) $(HAVE_BASERUBY:yes=extract-gems)
-prepare-gems: $(DOT_WAIT) $(HAVE_BASERUBY:yes=outdate-bundled-gems)
 extract-gems: $(HAVE_BASERUBY:yes=update-gems)
 
 update-gems$(gnumake:yes=-sequential): PHONY
@@ -1434,7 +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
@@ -1453,6 +1456,7 @@ 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)
@@ -1462,12 +1466,15 @@ yes-test-syntax-suggest-prepare: yes-test-syntax-suggest-precheck
 
 RSPECOPTS =
 SYNTAX_SUGGEST_SPECS =
+PREPARE_SYNTAX_SUGGEST = test-syntax-suggest-prepare
 test-syntax-suggest: $(TEST_RUNNABLE)-test-syntax-suggest
-yes-test-syntax-suggest: yes-test-syntax-suggest-prepare
+yes-test-syntax-suggest: yes-$(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 $(arch)-fake.rb
@@ -1580,31 +1587,31 @@ UNICODE_EMOJI_DOWNLOAD = \
 	    -d $(UNICODE_SRC_EMOJI_DATA_DIR) \
 	    -p emoji/$(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): \
@@ -1613,13 +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 $(srcdir)/lib/unicode_normalize/tables.rb \
@@ -3202,8 +3221,13 @@ compile.$(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): $(top_srcdir)/internal/class.h
@@ -3211,6 +3235,7 @@ complex.$(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): $(top_srcdir)/internal/object.h
@@ -3221,6 +3246,7 @@ complex.$(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): {$(VPATH)}backward/2/bool.h
@@ -3378,11 +3404,18 @@ complex.$(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): $(CCAN_DIR)/list/list.h
@@ -3393,12 +3426,14 @@ cont.$(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): $(top_srcdir)/internal/warnings.h
@@ -3419,6 +3454,7 @@ cont.$(OBJEXT): {$(VPATH)}constant.h
 cont.$(OBJEXT): {$(VPATH)}cont.c
 cont.$(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): {$(VPATH)}gc.h
@@ -3496,6 +3532,15 @@ cont.$(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): {$(VPATH)}internal/event.h
@@ -3571,6 +3616,8 @@ cont.$(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): {$(VPATH)}ruby_assert.h
@@ -5857,10 +5904,16 @@ enum.$(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): $(top_srcdir)/internal/error.h
@@ -5878,6 +5931,7 @@ enumerator.$(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): {$(VPATH)}backward/2/bool.h
@@ -5892,6 +5946,7 @@ enumerator.$(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): {$(VPATH)}internal/abi.h
@@ -6043,13 +6098,20 @@ enumerator.$(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): $(CCAN_DIR)/list/list.h
@@ -7018,6 +7080,7 @@ goruby.$(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): {$(VPATH)}internal/attr/restrict.h
@@ -8521,7 +8584,6 @@ loadpath.$(OBJEXT): {$(VPATH)}internal/warning_push.h
 loadpath.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
 loadpath.$(OBJEXT): {$(VPATH)}loadpath.c
 loadpath.$(OBJEXT): {$(VPATH)}missing.h
-loadpath.$(OBJEXT): {$(VPATH)}revision.h
 loadpath.$(OBJEXT): {$(VPATH)}st.h
 loadpath.$(OBJEXT): {$(VPATH)}subst.h
 loadpath.$(OBJEXT): {$(VPATH)}verconf.h
@@ -8856,8 +8918,13 @@ main.$(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): $(top_srcdir)/internal/class.h
@@ -8867,6 +8934,7 @@ marshal.$(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): $(top_srcdir)/internal/serial.h
@@ -8879,6 +8947,7 @@ marshal.$(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): {$(VPATH)}backward/2/bool.h
@@ -8894,6 +8963,7 @@ marshal.$(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): {$(VPATH)}internal.h
@@ -8934,6 +9004,7 @@ marshal.$(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): {$(VPATH)}internal/attr/restrict.h
@@ -9049,13 +9120,21 @@ marshal.$(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): $(top_srcdir)/internal/class.h
@@ -9231,12 +9310,16 @@ math.$(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): {$(VPATH)}backward/2/long_long.h
@@ -9476,6 +9559,7 @@ miniinit.$(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): {$(VPATH)}internal/attr/restrict.h
@@ -10443,8 +10527,13 @@ numeric.$(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): $(top_srcdir)/internal/class.h
@@ -10453,6 +10542,7 @@ object.$(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): $(top_srcdir)/internal/object.h
@@ -10465,6 +10555,7 @@ object.$(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): {$(VPATH)}backward/2/bool.h
@@ -10633,22 +10724,31 @@ object.$(OBJEXT): {$(VPATH)}internal/variable.h
 object.$(OBJEXT): {$(VPATH)}internal/warning_push.h
 object.$(OBJEXT): {$(VPATH)}internal/xmalloc.h
 object.$(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): $(top_srcdir)/internal/symbol.h
@@ -11057,6 +11157,7 @@ proc.$(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): $(top_srcdir)/internal/proc.h
@@ -11480,6 +11581,7 @@ ractor.$(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): $(top_srcdir)/internal/basic_operators.h
@@ -11675,6 +11777,7 @@ ractor.$(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): {$(VPATH)}oniguruma.h
@@ -11703,6 +11806,7 @@ random.$(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): $(top_srcdir)/internal/sanitizers.h
@@ -14217,6 +14321,7 @@ shape.$(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
@@ -14302,6 +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
@@ -14792,6 +14898,7 @@ 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
@@ -15057,6 +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
@@ -15498,6 +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
diff --git a/compile.c b/compile.c
index 8f53955e74..0452305923 100644
--- a/compile.c
+++ b/compile.c
@@ -1243,6 +1243,32 @@ 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)
@@ -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;
 }
 
@@ -1832,6 +1861,7 @@ iseq_set_arguments(rb_iseq_t *iseq, LINK_ANCHOR *const optargs, const NODE *cons
 
         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);
@@ -2630,9 +2660,11 @@ 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));
@@ -2668,6 +2700,8 @@ iseq_set_exception_table(rb_iseq_t *iseq)
         RB_OBJ_WRITE(iseq, &ISEQ_COMPILE_DATA(iseq)->catch_table_ary, 0); /* free */
     }
 
+    RB_GC_GUARD(catch_table_ary);
+
     return COMPILE_OK;
 }
 
@@ -2806,7 +2840,6 @@ remove_unreachable_chunk(rb_iseq_t *iseq, LINK_ELEMENT *i)
                 break;
             }
             else if ((lab = find_destination((INSN *)i)) != 0) {
-                if (lab->unremovable) break;
                 unref_counts[lab->label_no]++;
             }
         }
@@ -2823,8 +2856,7 @@ remove_unreachable_chunk(rb_iseq_t *iseq, LINK_ELEMENT *i)
             /* do nothing */
         }
         else if (IS_ADJUST(i)) {
-            LABEL *dest = ((ADJUST *)i)->label;
-            if (dest && dest->unremovable) return 0;
+            return 0;
         }
         end = i;
     } while ((i = i->next) != 0);
@@ -4588,7 +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;
@@ -5039,12 +5076,17 @@ compile_massign_lhs(rb_iseq_t *iseq, LINK_ANCHOR *const pre, LINK_ANCHOR *const
 
         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;
+        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;
@@ -5063,7 +5105,9 @@ compile_massign_lhs(rb_iseq_t *iseq, LINK_ANCHOR *const pre, LINK_ANCHOR *const
             return COMPILE_NG;
         }
 
-        ADD_ELEM(lhs, (LINK_ELEMENT *)iobj);
+        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);
@@ -5072,9 +5116,11 @@ compile_massign_lhs(rb_iseq_t *iseq, LINK_ANCHOR *const pre, LINK_ANCHOR *const
             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) {
+        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);
@@ -7611,7 +7657,6 @@ compile_next(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node, in
         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);
@@ -9276,7 +9321,8 @@ 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 &&
+    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 &&
@@ -9474,7 +9520,10 @@ iseq_compile_each0(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const no
       }
 
       case NODE_MASGN:{
+        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;
       }
 
@@ -9716,7 +9765,12 @@ iseq_compile_each0(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const no
       case NODE_LIT:{
         debugp_param("lit", node->nd_lit);
         if (!popped) {
-            ADD_INSN1(ret, node, putobject, node->nd_lit);
+            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;
@@ -10734,6 +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)
 {
@@ -10760,29 +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_IC: // constant path array
-                      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;
         }
@@ -12310,7 +12348,7 @@ ibf_load_iseq_each(struct ibf_load *load, rb_iseq_t *iseq, ibf_offset_t offset)
     verify_call_cache(iseq);
 
     RB_GC_GUARD(dummy_frame);
-    rb_vm_pop_frame(ec);
+    rb_vm_pop_frame_no_int(ec);
 }
 
 struct ibf_dump_iseq_list_arg
@@ -13061,7 +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
diff --git a/complex.c b/complex.c
index 57962f9013..a227cb0a58 100644
--- a/complex.c
+++ b/complex.c
@@ -2116,8 +2116,11 @@ nucomp_convert(VALUE klass, VALUE a1, VALUE a2, int raise)
             return a1;
         /* should raise exception for consistency */
         if (!k_numeric_p(a1)) {
-            if (!raise)
-                return rb_protect(to_complex, a1, NULL);
+            if (!raise) {
+                a1 = rb_protect(to_complex, a1, NULL);
+                rb_set_errinfo(Qnil);
+                return a1;
+            }
             return to_complex(a1);
         }
     }
diff --git a/configure.ac b/configure.ac
index ae560297ad..220392d120 100644
--- a/configure.ac
+++ b/configure.ac
@@ -214,15 +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)
@@ -366,12 +374,6 @@ AS_CASE(["$target_os"],
 	[AC_MSG_RESULT(yes)],
 	[AC_MSG_RESULT(no)
 	AC_MSG_ERROR([Unsupported OS X version is required])])
-    AC_CACHE_CHECK([if thread-local storage is supported], [rb_cv_tls_supported],
-	[AC_LINK_IFELSE([AC_LANG_PROGRAM([[int __thread conftest;]])],
-	    [rb_cv_tls_supported=yes],
-	    [rb_cv_tls_supported=no])])
-    AS_IF([test x"$rb_cv_tls_supported" != xyes],
-	[AC_DEFINE(RB_THREAD_LOCAL_SPECIFIER_IS_UNSUPPORTED)])
 ])
 
 RUBY_MINGW32
@@ -391,6 +393,13 @@ AS_IF([test "$GCC" = yes], [
     AS_IF([test "$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"$rb_cv_tls_supported" != xyes],
+        [AC_DEFINE(RB_THREAD_LOCAL_SPECIFIER_IS_UNSUPPORTED)])
 ], [
     linker_flag=
 ])
@@ -524,7 +533,9 @@ AS_IF([test "$cross_compiling:$ac_cv_prog_DTRACE" = no: -a -n "$ac_tool_prefix"]
 AC_CHECK_PROGS(DOT, dot)
 AC_CHECK_PROGS(DOXYGEN, doxygen)
 
+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], [],
 [
@@ -964,9 +975,10 @@ AS_IF([test "x$OPT_DIR" != x], [
     LDFLAGS="${LDFLAGS:+$LDFLAGS }$val"
     DLDFLAGS="${DLDFLAGS:+$DLDFLAGS }$val"
     LDFLAGS_OPTDIR="$val"
-    CPPFLAGS="${CPPFLAGS:+$CPPFLAGS }"`echo "$OPT_DIR" | tr "${PATH_SEPARATOR}" '\012' |
+    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 $ARCH_FLAG\""
@@ -1191,8 +1203,6 @@ main()
 		ac_cv_func_gmtime_r=yes
 		rb_cv_large_fd_select=yes
 		ac_cv_type_struct_timeval=yes
-                ac_cv_func_clock_gettime=yes
-                ac_cv_func_clock_getres=yes
 		ac_cv_func_malloc_usable_size=no
 		ac_cv_type_off_t=yes
 		ac_cv_sizeof_off_t=8
@@ -1338,6 +1348,8 @@ AC_CHECK_HEADERS(syscall.h)
 AC_CHECK_HEADERS(time.h)
 AC_CHECK_HEADERS(ucontext.h)
 AC_CHECK_HEADERS(utime.h)
+AC_CHECK_HEADERS(stdatomic.h)
+
 AS_CASE("$target_cpu", [x64|x86_64|i[3-6]86*], [
   AC_CHECK_HEADERS(x86intrin.h)
 ])
@@ -1354,6 +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} ${CPPFLAGS}"
   malloc_header=
   AC_CHECK_HEADER(jemalloc/jemalloc.h, [malloc_header=jemalloc/jemalloc.h], [
     AC_CHECK_HEADER(jemalloc.h, [malloc_header=jemalloc.h])
@@ -1385,6 +1399,8 @@ AS_IF([test "x$with_jemalloc" != xno],[
       done
     done
   ])
+  CPPFLAGS="${save_CPPFLAGS}"
+  unset save_CPPFLAGS
   with_jemalloc=${rb_cv_jemalloc_library}
   AS_CASE(["$with_jemalloc"],
   [no],
@@ -1995,6 +2011,7 @@ AC_CHECK_FUNCS(_longjmp)		# used for AC_ARG_WITH(setjmp-type)
 test x$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)
@@ -3049,7 +3066,7 @@ AC_SUBST(EXTOBJS)
 	[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
@@ -3352,6 +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='$(MINIRUBY)'
@@ -3785,7 +3806,7 @@ AS_IF([test "$cross_compiling" = no],
 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 experimental in-process JIT compiler that requires Rust build tools [default=no]]),
+    [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], [
diff --git a/cont.c b/cont.c
index e050deefdc..5375d1945b 100644
--- a/cont.c
+++ b/cont.c
@@ -29,6 +29,7 @@ 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"
@@ -1254,6 +1255,8 @@ jit_cont_new(rb_execution_context_t *ec)
 static void
 jit_cont_free(struct rb_jit_cont *cont)
 {
+    if (!cont) return;
+
     rb_native_mutex_lock(&jit_cont_lock);
     if (cont == first_jit_cont) {
         first_jit_cont = cont->next;
@@ -1578,7 +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;
@@ -1958,7 +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
@@ -2068,21 +2071,33 @@ fiber_storage_get(rb_fiber_t *fiber)
     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.current.storage -> hash (dup)
+ *  call-seq: fiber.storage -> hash (dup)
  *
- *  Returns a copy of the storage hash for the current fiber.
+ *  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)
 {
-    rb_check_id(&key);
+    Check_Type(key, T_SYMBOL);
 
     return ST_CONTINUE;
 }
@@ -2090,24 +2105,32 @@ fiber_storage_validate_each(VALUE key, VALUE value, VALUE _argument)
 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.current.storage = hash
+ *  call-seq: fiber.storage = hash
  *
- *  Sets the storage hash for the current fiber. This feature is experimental
- *  and may change in the future.
+ *  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#[]=.
+ *  keys in the storage using Fiber::[]=.
  *
- *  You can also use Fiber.new(storage: nil) to create a fiber with an empty
+ *  You can also use <tt>Fiber.new(storage: nil)</tt> to create a fiber with an empty
  *  storage.
  *
  *  Example:
@@ -2121,6 +2144,12 @@ fiber_storage_validate(VALUE value)
 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);
@@ -2130,18 +2159,17 @@ rb_fiber_storage_set(VALUE self, VALUE value)
 /**
  *  call-seq: Fiber[key] -> value
  *
- *  Returns the value of the fiber-local variable identified by +key+.
+ *  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[]=.
+ *  See also Fiber::[]=.
  */
 static VALUE
 rb_fiber_storage_aref(VALUE class, VALUE key)
 {
-    ID id = rb_check_id(&key);
-    if (!id) return Qnil;
+    Check_Type(key, T_SYMBOL);
 
     VALUE storage = fiber_storage_get(fiber_current());
 
@@ -2153,18 +2181,17 @@ rb_fiber_storage_aref(VALUE class, VALUE key)
 /**
  *  call-seq: Fiber[key] = value
  *
- *  Assign +value+ to the fiber-local variable identified by +key+.
+ *  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[].
+ *  See also Fiber::[].
  */
 static VALUE
 rb_fiber_storage_aset(VALUE class, VALUE key, VALUE value)
 {
-    ID id = rb_check_id(&key);
-    if (!id) return Qnil;
+    Check_Type(key, T_SYMBOL);
 
     VALUE storage = fiber_storage_get(fiber_current());
 
@@ -2178,9 +2205,6 @@ fiber_initialize(VALUE self, VALUE proc, struct fiber_pool * fiber_pool, unsigne
         // The default, inherit storage (dup) from the current fiber:
         storage = inherit_fiber_storage();
     }
-    else if (storage == Qfalse) {
-        storage = current_fiber_storage();
-    }
     else /* nil, hash, etc. */ {
         fiber_storage_validate(storage);
         storage = rb_obj_dup(storage);
@@ -2292,18 +2316,6 @@ rb_fiber_initialize_kw(int argc, VALUE* argv, VALUE self, int kw_splat)
  *    end.resume
  *    Fiber[:x] # => 1
  *
- *  If the <tt>storage</tt> is <tt>false</tt>, this function uses the current
- *  fiber's storage by reference. This is used for Enumerator to create
- *  hidden fiber.
- *
- *    Fiber[:count] = 0
- *    enumerator = Enumerator.new do |y|
- *      loop{y << (Fiber[:count] += 1)}
- *    end
- *    Fiber[:count] # => 0
- *    enumerator.next # => 1
- *    Fiber[:count] # => 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.
  *
@@ -2315,7 +2327,7 @@ rb_fiber_initialize_kw(int argc, VALUE* argv, VALUE self, int kw_splat)
  *  Otherwise, the given <tt>storage</tt> is used as the new fiber's storage,
  *  and it must be an instance of Hash.
  *
- *  Explicitly using `storage: true/false` is currently experimental and may
+ *  Explicitly using <tt>storage: true</tt> is currently experimental and may
  *  change in the future.
  */
 static VALUE
@@ -2327,7 +2339,7 @@ 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), 1, storage);
+    return fiber_initialize(fiber_alloc(rb_cFiber), rb_proc_new(func, obj), rb_fiber_pool_default(Qnil), 0, storage);
 }
 
 VALUE
@@ -2387,7 +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
@@ -2406,7 +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).
  *
  */
@@ -2440,7 +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.
@@ -2787,7 +2799,8 @@ rb_fiber_blocking(VALUE class)
     // If we are already blocking, this is essentially a no-op:
     if (fiber->blocking) {
         return rb_yield(fiber_value);
-    } else {
+    }
+    else {
         return rb_ensure(fiber_blocking_yield, fiber_value, fiber_blocking_ensure, fiber_value);
     }
 }
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/cygwin/GNUmakefile.in b/cygwin/GNUmakefile.in
index 43e92a27f0..f342d2fcf7 100644
--- a/cygwin/GNUmakefile.in
+++ b/cygwin/GNUmakefile.in
@@ -2,6 +2,9 @@ gnumake = yes
 
 include Makefile
 
+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)) \
@@ -63,7 +66,7 @@ $(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)
 
diff --git a/debug_counter.h b/debug_counter.h
index b0047685f0..6e0b8dee60 100644
--- a/debug_counter.h
+++ b/debug_counter.h
@@ -243,6 +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)
diff --git a/defs/gmake.mk b/defs/gmake.mk
index 0d79aba07d..54fef6685f 100644
--- a/defs/gmake.mk
+++ b/defs/gmake.mk
@@ -27,7 +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))
@@ -40,6 +40,7 @@ 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
@@ -83,7 +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 \
 	)
@@ -383,16 +385,10 @@ $(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 ($(HAVE_GIT),yes)
 REVISION_LATEST := $(shell $(CHDIR) $(srcdir) && $(GIT) log -1 --format=%H 2>/dev/null)
diff --git a/defs/id.def b/defs/id.def
index 94af02b12f..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>
diff --git a/doc/.document b/doc/.document
index 5ef2d99651..f589dda07c 100644
--- a/doc/.document
+++ b/doc/.document
@@ -6,3 +6,4 @@ NEWS
 syntax
 optparse
 rdoc
+yjit
diff --git a/doc/ChangeLog-2.3.0 b/doc/ChangeLog-2.3.0
index 629fd9c4ec..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>
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/mjit.md b/doc/mjit.md
deleted file mode 100644
index 9622a3bc26..0000000000
--- a/doc/mjit.md
+++ /dev/null
@@ -1,78 +0,0 @@
-# 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
-
-### Architectures
-
-## Bindgen
-
-If you see an "MJIT bindgen" GitHub Actions failure, please commit the `git diff` shown on the failed job.
-
-Refer to the following instructions for doing the same thing locally.
-Similar to `make yjit-bindgen`, `make mjit-bindgen` requires libclang.
-See also: [mjit-bindgen.yml](../.github/workflows/mjit-bindgen.yml)
-
-macOS seems to have libclang by default, but I'm not sure how to deal with 32bit architectures.
-For now, you may generate c\_64.rb with a 64bit binary, and then manually modify c\_32.rb accordingly.
-
-### x86\_64-linux
-
-```sh
-sudo apt install \
-  build-essential \
-  libssl-dev libyaml-dev libreadline6-dev \
-  zlib1g-dev libncurses5-dev libffi-dev \
-  libclang1
-./autogen.sh
-./configure --enable-yjit=dev_nodebug --disable-install-doc
-make -j
-make mjit-bindgen
-```
-
-### i686-linux
-
-```sh
-sudo dpkg --add-architecture i386
-sudo apt install \
-  crossbuild-essential:i386 \
-  libssl-dev:i386 libyaml-dev:i386 libreadline6-dev:i386 \
-  zlib1g-dev:i386 libncurses5-dev:i386 libffi-dev:i386 \
-  libclang1:i386
-./autogen.sh
-./configure --disable-install-doc
-make -j
-make mjit-bindgen
-```
-
-Note that you cannot run x86\_64 bindgen with an i686 binary, and vice versa.
-Also, when you install libclang1:i386, libclang1 will be uninstalled.
-You can have only either of these at a time.
-
-## Local development
-
-### 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/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
index dd4acecda6..c1366e7ad1 100644
--- a/doc/net-http/examples.rdoc
+++ b/doc/net-http/examples.rdoc
@@ -10,9 +10,10 @@ Many code examples here use these example websites:
 
 Some examples also assume these variables:
 
-  uri = URI('https://jsonplaceholder.typicode.com')
+  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:
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/packed_data.rdoc b/doc/packed_data.rdoc
index 9ba585c90b..ec13b24c69 100644
--- a/doc/packed_data.rdoc
+++ b/doc/packed_data.rdoc
@@ -60,6 +60,10 @@ Any directive may be followed by either of these modifiers:
   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
diff --git a/doc/syntax/literals.rdoc b/doc/syntax/literals.rdoc
index 5e10e6a140..b641433249 100644
--- a/doc/syntax/literals.rdoc
+++ b/doc/syntax/literals.rdoc
@@ -277,6 +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:
diff --git a/doc/yjit/yjit.md b/doc/yjit/yjit.md
index 1af5aeb417..67b2ffa5f0 100644
--- a/doc/yjit/yjit.md
+++ b/doc/yjit/yjit.md
@@ -9,9 +9,9 @@ YJIT - Yet Another Ruby JIT
 ===========================
 
 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.
-YJIT is currently supported for macOS and Linux on x86-64 and arm64/aarch64 CPUs.
+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>
@@ -20,6 +20,8 @@ This project is open source and falls under the same license as CRuby.
  </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)
@@ -52,8 +54,7 @@ series = {VMIL 2021}
 
 ## Current Limitations
 
-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.
+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
@@ -75,44 +76,53 @@ To install the Rust build toolchain, we suggest following the [recommended insta
 
 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. 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-compile-and-install).
+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).
 
-```
+```sh
 # Configure in release mode for maximum performance, build and install
 ./autogen.sh
 ./configure --enable-yjit --prefix=$HOME/.rubies/ruby-yjit --disable-install-doc
-make -j install
+make -j && make install
 ```
 
 or
 
-```
-# Configure in dev (debug) mode for development, build and install
+```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 install
+make -j && make install
 ```
 
-On macOS, you may need to specify where to find some libraries:
+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
 ```
+
+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 install
+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
 ```
@@ -121,7 +131,7 @@ before running `./configure`.
 
 You can test that YJIT works correctly by running:
 
-```
+```sh
 # Quick tests found in /bootstraptest
 make btest
 
@@ -136,14 +146,14 @@ make -j 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
 ```
 
@@ -155,11 +165,9 @@ YJIT supports all command-line options supported by upstream CRuby, but also add
 
 - `--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 128 MiB)
-- `--yjit-stats`: produce statistics after the execution of a program
-- `--yjit-trace-exits`: produce a Marshal dump of backtraces from specific exits. Automatically enables `--yjit-stats` (must configure and build with `--enable-yjit=stats` to use this)
-- `--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-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.
@@ -168,28 +176,79 @@ This can be useful for some deployment scripts where specifying an extra command
 
 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 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.
+This section goes over tips on minimizing YJIT memory usage in case it uses more than your capacity.
 
-- Use exceptions for error recovery only, not as part of normal control-flow
+### 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.
+
+## Code Optimization Tips
+
+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 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> RubyVM::YJIT.runtime_stats
 =>
@@ -205,16 +264,24 @@ irb(main):001:0> RubyVM::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.
@@ -242,8 +309,6 @@ The YJIT source code is divided between:
 - `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
-- `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
 
 The core of CRuby's interpreter logic is found in:
 - `insns.def`: defines Ruby's bytecode instructions (gets compiled into `vm.inc`)
@@ -274,38 +339,38 @@ There are 3 test suites:
 
 The tests can be run in parallel like this:
 
-```
+```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
 ```
 
@@ -316,7 +381,7 @@ instructions below, but there are a few caveats listed further down.
 
 First, install Rosetta:
 
-```
+```sh
 $ softwareupdate --install-rosetta
 ```
 
@@ -324,13 +389,13 @@ 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
@@ -338,7 +403,7 @@ i386
 
 You may need to set the default target for `rustc` to x86-64, e.g.
 
-```
+```sh
 $ rustup default stable-x86_64-apple-darwin
 ```
 
diff --git a/enc/Makefile.in b/enc/Makefile.in
index dd8ca1b528..9d0c367134 100644
--- a/enc/Makefile.in
+++ b/enc/Makefile.in
@@ -51,7 +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/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/encoding.c b/encoding.c
index b8e7f790b8..2f4b47bdfa 100644
--- a/encoding.c
+++ b/encoding.c
@@ -56,9 +56,8 @@ int rb_encdb_alias(const char *alias, const char *orig);
 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);
@@ -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
@@ -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_8BIT:    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
@@ -462,7 +422,7 @@ 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;
     }
@@ -484,11 +444,14 @@ 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);
     }
+    else if (!valid_encoding_name_p(name)) {
+        rb_raise(rb_eArgError, "invalid encoding name: %s", name);
+    }
 }
 
 static rb_encoding*
@@ -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);
@@ -727,7 +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;
         }
@@ -764,7 +723,7 @@ 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)
@@ -877,11 +836,9 @@ 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);
     }
@@ -1368,10 +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];
 }
 
@@ -1397,14 +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;
 }
 
@@ -1553,15 +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();
 # 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;
 }
@@ -1575,13 +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_8BIT;
+    int idx = enc_registered(&global_enc_table, "filesystem");
+    if (idx < 0) idx = ENCINDEX_ASCII_8BIT;
     return idx;
 }
 
@@ -1612,7 +1556,14 @@ enc_set_default_encoding(struct default_encoding *def, VALUE encoding, const cha
         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 {
@@ -1872,15 +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;
 }
 
@@ -1926,8 +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];
 }
@@ -1996,13 +1939,7 @@ 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);
 
@@ -2024,5 +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 391de0b337..b3c715e0a1 100644
--- a/enum.c
+++ b/enum.c
@@ -4459,7 +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:
diff --git a/enumerator.c b/enumerator.c
index a0c51b585c..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
@@ -132,7 +164,10 @@ 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
@@ -766,8 +801,7 @@ next_init(VALUE obj, struct enumerator *e)
 {
     VALUE curr = rb_fiber_current();
     e->dst = curr;
-    // We inherit the fiber storage by reference, not by copy, by specifying Qfalse here.
-    e->fib = rb_fiber_new_storage(next_i, obj, Qfalse);
+    e->fib = rb_fiber_new(next_i, obj);
     e->lookahead = Qundef;
 }
 
@@ -776,8 +810,16 @@ 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();
 
@@ -3403,7 +3445,7 @@ enumerator_plus(VALUE obj, VALUE eobj)
  *
  * The method used against each enumerable object is `each_entry`
  * instead of `each` so that the product of N enumerable objects
- * yields exactly N arguments in each iteration.
+ * 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.
@@ -3481,9 +3523,16 @@ enum_product_allocate(VALUE klass)
  *   e.size #=> 6
  */
 static VALUE
-enum_product_initialize(VALUE obj, VALUE enums)
+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);
@@ -3589,7 +3638,7 @@ product_each(VALUE obj, struct product_state *pstate)
         rb_block_call(eobj, id_each_entry, 0, NULL, product_each_i, (VALUE)pstate);
     }
     else {
-        rb_funcallv(pstate->block, id_call, pstate->argc, pstate->argv);
+        rb_funcall(pstate->block, id_call, 1, rb_ary_new_from_values(pstate->argc, pstate->argv));
     }
 
     return obj;
@@ -3687,6 +3736,7 @@ enum_product_inspect(VALUE obj)
 /*
  * 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
@@ -3695,18 +3745,29 @@ enum_product_inspect(VALUE obj)
  *   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(VALUE klass, VALUE enums)
+enumerator_s_product(int argc, VALUE *argv, VALUE klass)
 {
-    VALUE obj = enum_product_initialize(enum_product_allocate(rb_cEnumProduct), enums);
+    VALUE enums = Qnil, options = Qnil, block = Qnil;
 
-    if (rb_block_given_p()) {
-        return enum_product_run(obj, rb_block_proc());
+    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)));
     }
-    else {
-        return obj;
+
+    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;
 }
 
 /*
@@ -4586,7 +4647,7 @@ InitVM_Enumerator(void)
     /* 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, -2);
+    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);
@@ -4597,7 +4658,7 @@ InitVM_Enumerator(void)
     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, -2);
+    rb_define_singleton_method(rb_cEnumerator, "product", enumerator_s_product, -1);
 
     /* ArithmeticSequence */
     rb_cArithSeq = rb_define_class_under(rb_cEnumerator, "ArithmeticSequence", rb_cEnumerator);
diff --git a/error.c b/error.c
index e256f3bf37..726f57a4c0 100644
--- a/error.c
+++ b/error.c
@@ -420,7 +420,7 @@ rb_warn(const char *fmt, ...)
 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));
         }
@@ -452,7 +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));
         }
@@ -1818,7 +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;
 }
 
@@ -2959,6 +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)
 {
@@ -2973,6 +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);
     }
@@ -3024,14 +3030,16 @@ Init_Exception(void)
     rb_eSyntaxError = rb_define_class("SyntaxError", rb_eScriptError);
     rb_define_method(rb_eSyntaxError, "initialize", syntax_error_initialize, -1);
 
-    ID id_path = rb_intern_const("path");
+    /* 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, id_path, TRUE, FALSE, FALSE);
+    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, id_path, TRUE, FALSE, FALSE);
+    rb_attr(rb_eLoadError, path, TRUE, FALSE, FALSE);
 
     rb_eNotImpError = rb_define_class("NotImplementedError", rb_eScriptError);
 
diff --git a/eval.c b/eval.c
index e1bbf6f2c3..a61dfb1289 100644
--- a/eval.c
+++ b/eval.c
@@ -537,12 +537,16 @@ exc_setup_message(const rb_execution_context_t *ec, VALUE mesg, VALUE *cause)
     }
 
     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;
 }
@@ -643,6 +647,10 @@ rb_ec_setup_exception(const rb_execution_context_t *ec, VALUE mesg, VALUE cause)
         cause = get_ec_errinfo(ec);
     }
     if (cause != mesg) {
+        if (THROW_DATA_P(cause)) {
+            cause = Qnil;
+        }
+
         rb_ivar_set(mesg, id_cause, cause);
     }
 }
@@ -1769,6 +1777,16 @@ rb_obj_extend(int argc, VALUE *argv, VALUE 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
@@ -1781,13 +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"));
 }
 
 /*
diff --git a/eval_error.c b/eval_error.c
index e02f54e8e6..9806683000 100644
--- a/eval_error.c
+++ b/eval_error.c
@@ -291,6 +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;
@@ -444,7 +455,12 @@ exiting_split(VALUE errinfo, volatile int *exitcode, volatile int *sigstatus)
 
     if (NIL_P(errinfo)) return 0;
 
-    if (rb_obj_is_kind_of(errinfo, rb_eSystemExit)) {
+    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;
     }
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/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/date/date.gemspec b/ext/date/date.gemspec
index eecbf786a3..660353ebc5 100644
--- a/ext/date/date.gemspec
+++ b/ext/date/date.gemspec
@@ -10,15 +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 = [
-    "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"
-  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 e58da719e0..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);
     }
@@ -7432,6 +7437,96 @@ 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
@@ -8740,6 +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)
@@ -9370,6 +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
@@ -9691,6 +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
@@ -9901,6 +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_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 787fe85b93..a9fe3ce4b0 100644
--- a/ext/date/lib/date.rb
+++ b/ext/date/lib/date.rb
@@ -4,7 +4,7 @@
 require 'date_core'
 
 class Date
-  VERSION = "3.3.0" # :nodoc:
+  VERSION = "3.3.3" # :nodoc:
 
   # call-seq:
   #   infinite? -> false
diff --git a/ext/etc/etc.c b/ext/etc/etc.c
index fb27e63016..6c7145b40b 100644
--- a/ext/etc/etc.c
+++ b/ext/etc/etc.c
@@ -56,7 +56,7 @@ static VALUE sGroup;
 #endif
 char *getlogin();
 
-#define RUBY_ETC_VERSION "1.4.1"
+#define RUBY_ETC_VERSION "1.4.2"
 
 #ifdef HAVE_RB_DEPRECATE_CONSTANT
 void rb_deprecate_constant(VALUE mod, const char *name);
diff --git a/ext/extmk.rb b/ext/extmk.rb
index cab9a519c1..4e77a7167b 100755
--- a/ext/extmk.rb
+++ b/ext/extmk.rb
@@ -136,6 +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
@@ -163,8 +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
@@ -198,7 +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)) ||
@@ -261,6 +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]
@@ -549,7 +557,13 @@ 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/[^/]+(?=/))) {
diff --git a/ext/fiddle/extconf.rb b/ext/fiddle/extconf.rb