11281 files changed, 1540507 insertions, 536542 deletions

diff --git a/.appveyor.yml b/.appveyor.yml
new file mode 100644
index 0000000000..05ff204541
--- /dev/null
+++ b/.appveyor.yml
@@ -0,0 +1,134 @@
+---
+version: '{build}'
+init:
+  - git config --global user.name git
+  - git config --global user.email svn-admin@ruby-lang.org
+  - git config --global core.autocrlf false
+  - git config --global core.eol lf
+  - git config --global advice.detachedHead 0
+shallow_clone: true
+clone_depth: 10
+platform:
+  - x64
+skip_commits:
+  message: /\[DOC\]/
+  files:
+    - doc/*
+    - '**/*.md'
+    - '**/*.rdoc'
+    - '**/.document'
+    - '**/*.[1-8]'
+    - '**/*.ronn'
+environment:
+  ruby_version: "24-%Platform%"
+  matrix:
+    # Test only the oldest supported version because AppVeyor is unstable, its concurrency
+    # is limited, and compatibility issues that happen only in newer versions are rare.
+    # You may test some other stuff on GitHub Actions instead.
+    - build: vs
+      vs: 120 # 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"
+cache:
+  - c:\Tools\vcpkg\installed\
+for:
+-
+  matrix:
+    only:
+      - build: vs
+  install:
+    - ver
+    - chcp
+    - SET BITS=%Platform:x86=32%
+    - SET BITS=%BITS:x=%
+    - SET OPENSSL_DIR=C:\%ssl%-Win%BITS%
+    - 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
+    - SET vcvars
+    - '"%vcvars%" %Platform:x64=amd64%'
+    - SET ruby_path=C:\Ruby%ruby_version:-x86=%
+    - SET PATH=\usr\local\bin;%ruby_path%\bin;%PATH%;C:\msys64\mingw64\bin;C:\msys64\usr\bin
+    - ruby --version
+    - 'cl'
+    - echo> Makefile srcdir=.
+    - echo>> Makefile MSC_VER=0
+    - echo>> Makefile RT=none
+    - echo>> Makefile RT_VER=0
+    - echo>> Makefile BUILTIN_ENCOBJS=nul
+    - type win32\Makefile.sub >> Makefile
+    - nmake %mflags% up VCSUP="echo Update OK"
+    - nmake %mflags% extract-extlibs
+    - del Makefile
+    - mkdir \usr\local\bin
+    - mkdir \usr\local\include
+    - mkdir \usr\local\lib
+    - for %%I in (%OPENSSL_DIR%\*.dll) do mklink /h \usr\local\bin\%%~nxI %%I
+    - for %%I in (c:\Tools\vcpkg\installed\%Platform%-windows\bin\*.dll) do (
+        if not %%~nI == readline mklink \usr\local\bin\%%~nxI %%I
+      )
+    - attrib +r /s /d
+    - mkdir %Platform%-mswin_%vs%
+  build_script:
+    - set HAVE_GIT=no
+    - cd %APPVEYOR_BUILD_FOLDER%
+    - cd %Platform%-mswin_%vs%
+    - >-
+      ..\win32\configure.bat
+      --with-opt-dir="/usr/local;c:/Tools/vcpkg/installed/%Platform%-windows"
+      --with-openssl-dir=%OPENSSL_DIR:\=/%
+    - nmake -l
+    - nmake install-nodoc
+    - \usr\bin\ruby -v -e "p :locale => Encoding.find('locale'), :filesystem => Encoding.find('filesystem')"
+    - if not "%GEMS_FOR_TEST%" == "" \usr\bin\gem install --no-document %GEMS_FOR_TEST%
+    - \usr\bin\ruby -ropenssl -e "puts 'Build    ' + OpenSSL::OPENSSL_VERSION, 'Runtime  ' + OpenSSL::OPENSSL_LIBRARY_VERSION"
+  test_script:
+    - set /a JOBS=%NUMBER_OF_PROCESSORS%
+    - nmake -l "TESTOPTS=-v -q" btest
+    - nmake -l "TESTOPTS=-v -q" test-basic
+    - >-
+      nmake -l "TESTOPTS=--timeout-scale=3.0
+      --excludes=../test/excludes/_appveyor -j%JOBS%
+      --exclude win32ole
+      --exclude test_bignum
+      --exclude test_syntax
+      --exclude test_open-uri
+      --exclude test_bundled_ca
+      " test-all
+    # separately execute tests without -j which may crash worker with -j.
+    - >-
+      nmake -l
+      "TESTOPTS=--timeout-scale=3.0 --excludes=../test/excludes/_appveyor"
+      TESTS="
+      ../test/win32ole
+      ../test/ruby/test_bignum.rb
+      ../test/ruby/test_syntax.rb
+      ../test/open-uri/test_open-uri.rb
+      ../test/rubygems/test_bundled_ca.rb
+      " test-all
+    - nmake -l test-spec MSPECOPT=-fs # not using `-j` because sometimes `mspec -j` silently dies on Windows
+notifications:
+  - provider: Webhook
+    method: POST
+    url:
+      secure: CcFlJNDJ/a6to7u3Z4Fnz6dScEPNx7hTha2GkSRlV+1U6dqmxY/7uBcLXYb9gR3jfQk6w+2o/HrjNAyXMNGU/JOka3s2WRI4VKitzM+lQ08owvJIh0R7LxrGH0J2e81U # ruby-lang slack: ruby/simpler-alerts-bot
+    body: >-
+      {{^isPullRequest}}
+        {
+          "ci": "AppVeyor CI",
+          "env": "Visual Studio 2013",
+          "url": "{{buildUrl}}",
+          "commit": "{{commitId}}",
+          "branch": "{{branch}}"
+        }
+      {{/isPullRequest}}
+    on_build_success: false
+    on_build_failure: true
+    on_build_status_changed: false
diff --git a/.dir-locals.el b/.dir-locals.el
new file mode 100644
index 0000000000..8f4b96445c
--- /dev/null
+++ b/.dir-locals.el
@@ -0,0 +1,39 @@
+;; Copyright (c) 2018 Urabe, Shyouhei.  All rights reserved.
+;;
+;; This file is a part of  the programming language Ruby.  Permission is hereby
+;; granted, to either  redistribute and/or modify this file,  provided that the
+;; conditions mentioned  in the  file COPYING  are met.   Consult the  file for
+;; details.
+
+((nil .
+     ((indent-tabs-mode . nil)
+      (require-final-newline . t)
+      (tab-width . 8)
+      (show-trailing-whitespace . t)
+      (whitespace-line-column . 80))) ;; See also [Misc #12277]
+
+ ;; (bat-mode . ((buffer-file-coding-system . utf-8-dos)))
+
+ (ruby-mode . ((ruby-indent-level . 2)))
+
+ (rdoc-mode . ((fill-column . 74)))
+
+ (yaml-mode . ((yaml-indent-offset . 2)))
+
+ (makefile-mode . ((indent-tabs-mode . t)))
+
+ (c-mode . ((c-file-style . "ruby")))
+
+ (c++-mode . ((c-file-style . "ruby")))
+
+ (change-log-mode .
+     ((buffer-file-coding-system . us-ascii)
+      (indent-tabs-mode . t)
+      (change-log-indent-text . 2)
+      (add-log-time-format . (lambda (&optional x y)
+        (let* ((time (or x (current-time)))
+	       (system-time-locale "C")
+	       (diff (+ (cadr time) 32400))
+	       (lo (% diff 65536))
+	       (hi (+ (car time) (/ diff 65536))))
+        (format-time-string "%a %b %e %H:%M:%S %Y" (list hi lo) t)))))))
diff --git a/.document b/.document
index fb27ba325d..3a6b0c238c 100644
--- a/.document
+++ b/.document
@@ -5,9 +5,31 @@
 
 # Process all the C source files
 *.c
+*.y
 
 # prelude
 prelude.rb
+rbconfig.rb
+
+array.rb
+ast.rb
+dir.rb
+gc.rb
+io.rb
+kernel.rb
+marshal.rb
+mjit.rb
+numeric.rb
+nilclass.rb
+pack.rb
+ractor.rb
+string.rb
+symbol.rb
+timev.rb
+thread_sync.rb
+trace_point.rb
+warning.rb
+yjit.rb
 
 # the lib/ directory (which has its own .document file)
 lib
@@ -16,11 +38,17 @@ lib
 ext
 
 # rdoc files
-ChangeLog
-
-NEWS
+NEWS.md
 
 README.md
 README.ja.md
 
+COPYING
+COPYING.ja
+
+LEGAL
+
+# win32/README.win32 linked from README.md
+win32
+
 doc
diff --git a/.editorconfig b/.editorconfig
index 67abf4b978..4633a7acae 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -2,15 +2,29 @@ root = true
 
 [*]
 end_of_line = lf
+indent_size = 4
+indent_style = space
 insert_final_newline = true
-trim_trailing_whitespace = true
 tab_width = 8
-indent_style = tab
-indent_size = 4
+trim_trailing_whitespace = true
 
-[**.bat]
+[*.bat]
 end_of_line = crlf
 
-[**.rb]
-indent_style = space
+[*.gemspec]
+indent_size = 2
+
+[*.rb]
+indent_size = 2
+
+[*.yml]
+indent_size = 2
+
+[{*[Mm]akefile*,*.mak,*.mk,depend}]
+indent_style = tab
+
+[enc/*]
+indent_size = 2
+
+[reg*.[ch]]
 indent_size = 2
diff --git a/.gdbinit b/.gdbinit
index 5735c65c1a..34d044caf6 100644
--- a/.gdbinit
+++ b/.gdbinit
@@ -1,3 +1,5 @@
+set startup-with-shell off
+
 define hook-run
   set $color_type = 0
   set $color_highlite = 0
@@ -63,7 +65,15 @@ define rp
   else
   if ($flags & RUBY_T_MASK) == RUBY_T_OBJECT
     printf "%sT_OBJECT%s: ", $color_type, $color_end
-    print (struct RObject *)($arg0)
+    print ((struct RObject *)($arg0))->basic
+    if ($flags & ROBJECT_EMBED)
+      print/x *((VALUE*)((struct RObject*)($arg0))->as.ary) @ (ROBJECT_EMBED_LEN_MAX+0)
+    else
+      print (((struct RObject *)($arg0))->as.heap)
+      if (((struct RObject*)($arg0))->as.heap.numiv) > 0
+        print/x *(((struct RObject*)($arg0))->as.heap.ivptr) @ (((struct RObject*)($arg0))->as.heap.numiv)
+      end
+    end
   else
   if ($flags & RUBY_T_MASK) == RUBY_T_CLASS
     printf "%sT_CLASS%s%s: ", $color_type, ($flags & RUBY_FL_SINGLETON) ? "*" : "", $color_end
@@ -89,14 +99,15 @@ define rp
     set $regsrc = ((struct RRegexp*)($arg0))->src
     set $rsflags = ((struct RBasic*)$regsrc)->flags
     printf "%sT_REGEXP%s: ", $color_type, $color_end
+    set $len = ($rsflags & RUBY_FL_USER1) ? \
+            ((struct RString*)$regsrc)->as.heap.len : \
+            (($rsflags & (RUBY_FL_USER2|RUBY_FL_USER3|RUBY_FL_USER4|RUBY_FL_USER5|RUBY_FL_USER6)) >> RUBY_FL_USHIFT+2)
     set print address off
-    output (char *)(($rsflags & RUBY_FL_USER1) ? \
+    output *(char *)(($rsflags & RUBY_FL_USER1) ? \
 	    ((struct RString*)$regsrc)->as.heap.ptr : \
-	    ((struct RString*)$regsrc)->as.ary)
+	    ((struct RString*)$regsrc)->as.ary) @ $len
     set print address on
-    printf " len:%ld ", ($rsflags & RUBY_FL_USER1) ? \
-            ((struct RString*)$regsrc)->as.heap.len : \
-            (($rsflags & (RUBY_FL_USER2|RUBY_FL_USER3|RUBY_FL_USER4|RUBY_FL_USER5|RUBY_FL_USER6)) >> RUBY_FL_USHIFT+2)
+    printf " len:%ld ", $len
     if $flags & RUBY_FL_USER6
       printf "(none) "
     end
@@ -117,7 +128,7 @@ define rp
       if ($len == 0)
 	printf "{(empty)} "
       else
-	output/x *((VALUE*)((struct RArray*)($arg0))->as.ary) @ $len
+	print/x *((VALUE*)((struct RArray*)($arg0))->as.ary) @ $len
 	printf " "
       end
     else
@@ -125,7 +136,7 @@ define rp
       printf "%sT_ARRAY%s: len=%ld ", $color_type, $color_end, $len
       if ($flags & RUBY_FL_USER2)
 	printf "(shared) shared="
-	output/x ((struct RArray*)($arg0))->as.heap.aux.shared
+	output/x ((struct RArray*)($arg0))->as.heap.aux.shared_root
 	printf " "
       else
 	printf "(ownership) capa=%ld ", ((struct RArray*)($arg0))->as.heap.aux.capa
@@ -133,7 +144,7 @@ define rp
       if ($len == 0)
 	printf "{(empty)} "
       else
-	output/x *((VALUE*)((struct RArray*)($arg0))->as.heap.ptr) @ $len
+	print/x *((VALUE*)((struct RArray*)($arg0))->as.heap.ptr) @ $len
 	printf " "
       end
     end
@@ -145,34 +156,27 @@ define rp
   else
   if ($flags & RUBY_T_MASK) == RUBY_T_HASH
     printf "%sT_HASH%s: ", $color_type, $color_end,
-    if ((struct RHash *)($arg0))->ntbl
-      printf "len=%ld ", ((struct RHash *)($arg0))->ntbl->num_entries
+    if (((struct RHash *)($arg0))->basic.flags & RHASH_ST_TABLE_FLAG)
+      printf "st len=%ld ", ((struct RHash *)($arg0))->as.st->num_entries
+    else
+      printf "li len=%ld bound=%ld ", \
+        ((((struct RHash *)($arg0))->basic.flags & RHASH_AR_TABLE_SIZE_MASK) >> RHASH_AR_TABLE_SIZE_SHIFT), \
+        ((((struct RHash *)($arg0))->basic.flags & RHASH_AR_TABLE_BOUND_MASK) >> RHASH_AR_TABLE_BOUND_SHIFT)
     end
     print (struct RHash *)($arg0)
   else
   if ($flags & RUBY_T_MASK) == RUBY_T_STRUCT
-    printf "%sT_STRUCT%s: len=%ld ", $color_type, $color_end, \
-      (($flags & (RUBY_FL_USER1|RUBY_FL_USER2)) ? \
+    set $len = (($flags & (RUBY_FL_USER1|RUBY_FL_USER2)) ? \
        ($flags & (RUBY_FL_USER1|RUBY_FL_USER2)) >> (RUBY_FL_USHIFT+1) : \
        ((struct RStruct *)($arg0))->as.heap.len)
+    printf "%sT_STRUCT%s: len=%ld ", $color_type, $color_end, $len
     print (struct RStruct *)($arg0)
-    x/xw (($flags & (RUBY_FL_USER1|RUBY_FL_USER2)) ? \
-          ((struct RStruct *)($arg0))->as.ary : \
-          ((struct RStruct *)($arg0))->as.heap.ptr)
+    output/x *(($flags & (RUBY_FL_USER1|RUBY_FL_USER2)) ? \
+              ((struct RStruct *)($arg0))->as.ary : \
+              ((struct RStruct *)($arg0))->as.heap.ptr) @ $len
   else
   if ($flags & RUBY_T_MASK) == RUBY_T_BIGNUM
-    printf "%sT_BIGNUM%s: sign=%d len=%ld ", $color_type, $color_end, \
-      (($flags & RUBY_FL_USER1) != 0), \
-      (($flags & RUBY_FL_USER2) ? \
-       ($flags & (RUBY_FL_USER5|RUBY_FL_USER4|RUBY_FL_USER3)) >> (RUBY_FL_USHIFT+3) : \
-       ((struct RBignum*)($arg0))->as.heap.len)
-    if $flags & RUBY_FL_USER2
-      printf "(embed) "
-    end
-    print (struct RBignum *)($arg0)
-    x/xw (($flags & RUBY_FL_USER2) ? \
-          ((struct RBignum*)($arg0))->as.ary : \
-          ((struct RBignum*)($arg0))->as.heap.digits)
+    rp_bignum $arg0
   else
   if ($flags & RUBY_T_MASK) == RUBY_T_RATIONAL
     printf "%sT_RATIONAL%s: ", $color_type, $color_end
@@ -247,7 +251,7 @@ define rp
   else
   if ($flags & RUBY_T_MASK) == RUBY_T_IMEMO
     printf "%sT_IMEMO%s(", $color_type, $color_end
-    output (enum imemo_type)(($flags>>RUBY_FL_USHIFT)&imemo_mask)
+    output (enum imemo_type)(($flags>>RUBY_FL_USHIFT)&RUBY_IMEMO_MASK)
     printf "): "
     rp_imemo $arg0
   else
@@ -261,6 +265,10 @@ define rp
     printf "%sT_ZOMBIE%s: ", $color_type, $color_end
     print (struct RData *)($arg0)
   else
+  if ($flags & RUBY_T_MASK) == RUBY_T_MOVED
+    printf "%sT_MOVED%s: ", $color_type, $color_end
+    print *(struct RMoved *)$arg0
+  else
     printf "%sunknown%s: ", $color_type, $color_end
     print (struct RBasic *)($arg0)
   end
@@ -296,6 +304,7 @@ define rp
   end
   end
   end
+  end
 end
 document rp
   Print a Ruby's VALUE.
@@ -327,6 +336,9 @@ define rp_id
   if $id == idLTLT
     printf "(:<<)\n"
   else
+  if $id == idGTGT
+    printf "(:>>)\n"
+  else
   if $id == idLE
     printf "(:<=)\n"
   else
@@ -354,6 +366,18 @@ define rp_id
   if $id == idASET
     printf "(:[]=)\n"
   else
+  if $id == idCOLON2
+    printf "(:'::')\n"
+  else
+  if $id == idANDOP
+    printf "(:&&)\n"
+  else
+  if $id == idOROP
+    printf "(:||)\n"
+  else
+  if $id == idANDDOT
+    printf "(:&.)\n"
+  else
     if $id <= tLAST_OP_ID
       printf "O"
     else
@@ -385,12 +409,13 @@ define rp_id
       end
     end
     printf "(%ld): ", $id
-    set $str = lookup_id_str($id)
-    if $str
-      rp_string $str
-    else
-      echo undef\n
-    end
+    print_id $id
+    echo \n
+  end
+  end
+  end
+  end
+  end
   end
   end
   end
@@ -415,21 +440,33 @@ end
 
 define output_string
   set $flags = ((struct RBasic*)($arg0))->flags
-  printf "%s", (char *)(($flags & RUBY_FL_USER1) ? \
+  set $len = ($flags & RUBY_FL_USER1) ? \
+          ((struct RString*)($arg0))->as.heap.len : \
+          (($flags & (RUBY_FL_USER2|RUBY_FL_USER3|RUBY_FL_USER4|RUBY_FL_USER5|RUBY_FL_USER6)) >> RUBY_FL_USHIFT+2)
+  if $len > 0
+    output *(char *)(($flags & RUBY_FL_USER1) ? \
 	    ((struct RString*)($arg0))->as.heap.ptr : \
-	    ((struct RString*)($arg0))->as.ary)
+	    ((struct RString*)($arg0))->as.ary) @ $len
+  else
+    output ""
+  end
 end
 
-define rp_string
+define print_string
   set $flags = ((struct RBasic*)($arg0))->flags
-  set print address off
-  output (char *)(($flags & RUBY_FL_USER1) ? \
-	    ((struct RString*)($arg0))->as.heap.ptr : \
-	    ((struct RString*)($arg0))->as.ary)
-  set print address on
-  printf " bytesize:%ld ", ($flags & RUBY_FL_USER1) ? \
+  set $len = ($flags & RUBY_FL_USER1) ? \
           ((struct RString*)($arg0))->as.heap.len : \
           (($flags & (RUBY_FL_USER2|RUBY_FL_USER3|RUBY_FL_USER4|RUBY_FL_USER5|RUBY_FL_USER6)) >> RUBY_FL_USHIFT+2)
+  if $len > 0
+    printf "%s", *(char *)(($flags & RUBY_FL_USER1) ? \
+	    ((struct RString*)($arg0))->as.heap.ptr : \
+	    ((struct RString*)($arg0))->as.ary) @ $len
+  end
+end
+
+define rp_string
+  output_string $arg0
+  printf " bytesize:%ld ", $len
   if !($flags & RUBY_FL_USER1)
     printf "(embed) "
   else
@@ -460,22 +497,67 @@ document rp_string
   Print the content of a String.
 end
 
+define rp_bignum
+  set $flags = ((struct RBignum*)($arg0))->basic.flags
+  set $len = (($flags & RUBY_FL_USER2) ? \
+       ($flags & (RUBY_FL_USER5|RUBY_FL_USER4|RUBY_FL_USER3)) >> (RUBY_FL_USHIFT+3) : \
+       ((struct RBignum*)($arg0))->as.heap.len)
+  printf "%sT_BIGNUM%s: sign=%d len=%ld ", $color_type, $color_end, \
+         (($flags & RUBY_FL_USER1) != 0), $len
+  if $flags & RUBY_FL_USER2
+    printf "(embed) "
+  end
+  print (struct RBignum *)($arg0)
+  set $ptr = (($flags & RUBY_FL_USER2) ? \
+              ((struct RBignum*)($arg0))->as.ary : \
+              ((struct RBignum*)($arg0))->as.heap.digits)
+  set $len = $len-1
+  printf "0x%x", $ptr[$len]
+  while $len > 0
+    set $len = $len-1
+    set $val = $ptr[$len]
+    set $w = sizeof($ptr[0])
+    printf "_"
+    if $w > 8
+      printf "%.32x", $val
+    else
+    if $w > 4
+      printf "%.16x", $val
+    else
+    if $w > 2
+      printf "%.8x", $val
+    else
+    if $w > 1
+      printf "%.4x", $val
+    else
+      printf "%.2x", $val
+    end
+    end
+    end
+    end
+  end
+  printf "\n"
+end
+document rp_bignum
+  Print the content of a Bignum.
+end
+
 define rp_class
   printf "(struct RClass *) %p", (void*)$arg0
-  if ((struct RClass *)($arg0))->ptr.origin_ != $arg0
-    printf " -> %p", ((struct RClass *)($arg0))->ptr.origin_
+  if RCLASS_ORIGIN((struct RClass *)($arg0)) != $arg0
+    printf " -> %p", RCLASS_ORIGIN((struct RClass *)($arg0))
   end
   printf "\n"
   rb_classname $arg0
-  print *(struct RClass *)($arg0)
-  print *((struct RClass *)($arg0))->ptr
+  print/x *(struct RClass *)($arg0)
+  print *RCLASS_EXT((struct RClass *)($arg0))
 end
 document rp_class
   Print the content of a Class/Module.
 end
 
 define rp_imemo
-  set $flags = (enum imemo_type)((((struct RBasic *)($arg0))->flags >> RUBY_FL_USHIFT) & imemo_mask)
+  set $flags = (enum imemo_type)((((struct RBasic *)($arg0))->flags >> RUBY_FL_USHIFT) & RUBY_IMEMO_MASK)
   if $flags == imemo_cref
     printf "(rb_cref_t *) %p\n", (void*)$arg0
     print *(rb_cref_t *)$arg0
@@ -627,12 +709,6 @@ define nd_cval
   rp ($arg0).u3.value
 end
 
-
-define nd_cnt
-  printf "%su3.cnt%s: ", $color_highlite, $color_end
-  p ($arg0).u3.cnt
-end
-
 define nd_tbl
   printf "%su1.tbl%s: ", $color_highlite, $color_end
   p ($arg0).u1.tbl
@@ -671,12 +747,6 @@ define nd_lit
   rp ($arg0).u1.value
 end
 
-
-define nd_frml
-  printf "%su1.node%s: ", $color_highlite, $color_end
-  rp ($arg0).u1.node
-end
-
 define nd_rest
   printf "%su2.argc%s: ", $color_highlite, $color_end
   p ($arg0).u2.argc
@@ -703,12 +773,6 @@ define nd_args
   rp ($arg0).u3.node
 end
 
-
-define nd_noex
-  printf "%su1.id%s: ", $color_highlite, $color_end
-  p ($arg0).u1.id
-end
-
 define nd_defn
   printf "%su3.node%s: ", $color_highlite, $color_end
   rp ($arg0).u3.node
@@ -726,17 +790,6 @@ define nd_new
 end
 
 
-define nd_cfnc
-  printf "%su1.cfunc%s: ", $color_highlite, $color_end
-  p ($arg0).u1.cfunc
-end
-
-define nd_argc
-  printf "%su2.argc%s: ", $color_highlite, $color_end
-  p ($arg0).u2.argc
-end
-
-
 define nd_cname
   printf "%su1.id%s: ", $color_highlite, $color_end
   p ($arg0).u1.id
@@ -798,7 +851,7 @@ end
 
 define nd_tree
   set $buf = (struct RString *)rb_str_buf_new(0)
-  call dump_node((VALUE)($buf), rb_str_new(0, 0), 0, ($arg0))
+  call dump_node((VALUE)($buf), rb_str_tmp_new(0), 0, ($arg0))
   printf "%s\n", $buf->as.heap.ptr
 end
 
@@ -869,8 +922,7 @@ end
 
 define rb_classname
   # up to 128bit int
-  set $rb_classname_permanent = "0123456789ABCDEF"
-  set $rb_classname = classname($arg0, $rb_classname_permanent)
+  set $rb_classname = rb_mod_name($arg0)
   if $rb_classname != RUBY_Qnil
     rp $rb_classname
   else
@@ -919,7 +971,7 @@ define iseq
 end
 
 define rb_ps
-  rb_ps_vm ruby_current_vm
+  rb_ps_vm ruby_current_vm_ptr
 end
 document rb_ps
 Dump all threads and their callstacks
@@ -927,8 +979,8 @@ end
 
 define rb_ps_vm
   print $ps_vm = (rb_vm_t*)$arg0
-  set $ps_thread_ln = $ps_vm->living_threads.n.next
-  set $ps_thread_ln_last = $ps_vm->living_threads.n.prev
+  set $ps_thread_ln      = $ps_vm->ractor.main_ractor.threads.set.n.next
+  set $ps_thread_ln_last = $ps_vm->ractor.main_ractor.threads.set.n.prev
   while 1
     set $ps_thread_th = (rb_thread_t *)$ps_thread_ln
     set $ps_thread = (VALUE)($ps_thread_th->self)
@@ -951,55 +1003,84 @@ define print_lineno
     set $pos = $pos - 1
   end
 
-  set $i = 0
-  set $size = $iseq->body->line_info_size
-  set $table = $iseq->body->line_info_table
+  set $index = 0
+  set $size = $iseq->body->insns_info.size
+  set $table = $iseq->body->insns_info.body
+  set $positions = $iseq->body->insns_info.positions
   #printf "size: %d\n", $size
   if $size == 0
   else
-    set $i = 1
-    while $i < $size
-      #printf "table[%d]: position: %d, line: %d, pos: %d\n", $i, $table[$i].position, $table[$i].line_no, $pos
-      if $table[$i].position > $pos
-        loop_break
+  if $size == 1
+    printf "%d", $table[0].line_no
+  else
+    if $positions
+      # get_insn_info_linear_search
+      set $index = 1
+      while $index < $size
+        #printf "table[%d]: position: %d, line: %d, pos: %d\n", $i, $positions[$i], $table[$i].line_no, $pos
+        if $positions[$index] > $pos
+          loop_break
+        end
+        set $index = $index + 1
+        if $positions[$index] == $pos
+          loop_break
+        end
       end
-      set $i = $i + 1
-      if $table[$i].position == $pos
-        loop_break
+    else
+      # get_insn_info_succinct_bitvector
+      set $sd = $iseq->body->insns_info.succ_index_table
+      set $immediate_table_size = sizeof($sd->imm_part) / sizeof(uint64_t) * 9
+      if $pos < $immediate_table_size
+        set $i = $pos / 9
+        set $j = $pos % 9
+        set $index = ((int)($sd->imm_part[$i] >> ($j * 7))) & 0x7f
+      else
+        set $block_index = ($pos - $immediate_table_size) / 512
+        set $block = &$sd->succ_part[$block_index]
+        set $block_bit_index = ($pos - $immediate_table_size) % 512
+        set $small_block_index = $block_bit_index / 64
+        set $small_block_popcount = $small_block_index == 0 ? 0 : (((int)($block->small_block_ranks >> (($small_block_index - 1) * 9))) & 0x1ff)
+        set $x = $block->bits[$small_block_index] << (63 - $block_bit_index % 64)
+        set $x = ($x & 0x5555555555555555) + ($x >> 1 & 0x5555555555555555)
+        set $x = ($x & 0x3333333333333333) + ($x >> 2 & 0x3333333333333333)
+        set $x = ($x & 0x0707070707070707) + ($x >> 4 & 0x0707070707070707)
+        set $x = ($x & 0x001f001f001f001f) + ($x >> 8 & 0x001f001f001f001f)
+        set $x = ($x & 0x0000003f0000003f) + ($x >>16 & 0x0000003f0000003f)
+        set $popcnt = ($x & 0x7f) + ($x >>32 & 0x7f)
+        set $index = $block->rank + $small_block_popcount + $popcnt
       end
     end
-    printf "%d", $table[$i-1].line_no
+    printf "%d", $table[$index-1].line_no
+  end
   end
 end
 
 define check_method_entry
-  # get $immeo and $can_be_svar and return $me
   set $imemo = (struct RBasic *)$arg0
-  set $can_be_svar = $arg1
-  if $imemo != Qfalse
+  if $imemo != RUBY_Qfalse
     set $type = ($imemo->flags >> 12) & 0x07
     if $type == imemo_ment
       set $me = (rb_callable_method_entry_t *)$imemo
     else
     if $type == imemo_svar
-      set $imemo == ((struct vm_svar *)$imemo)->cref_or_me
-      check_method_entry $imemo 0
+      set $imemo = ((struct vm_svar *)$imemo)->cref_or_me
+      check_method_entry $imemo
     end
     end
   end
 end
 
-define output_id
+define print_id
   set $id = $arg0
   # rb_id_to_serial
   if $id > tLAST_OP_ID
-    set $serial = (rb_id_serial_t)($id >> ID_SCOPE_SHIFT)
+    set $serial = (rb_id_serial_t)($id >> RUBY_ID_SCOPE_SHIFT)
   else
     set $serial = (rb_id_serial_t)$id
   end
-  if $serial && $serial <= global_symbols.last_id
+  if $serial && $serial <= ruby_global_symbols.last_id
     set $idx = $serial / ID_ENTRY_UNIT
-    set $ids = (struct RArray *)global_symbols.ids
+    set $ids = (struct RArray *)ruby_global_symbols.ids
     set $flags = $ids->basic.flags
     if ($flags & RUBY_FL_USER1)
       set $idsptr = $ids->as.ary
@@ -1011,7 +1092,7 @@ define output_id
     if $idx < $idslen
       set $t = 0
       set $ary = (struct RArray *)$idsptr[$idx]
-      if $ary != Qnil
+      if $ary != RUBY_Qnil
         set $flags = $ary->basic.flags
         if ($flags & RUBY_FL_USER1)
           set $aryptr = $ary->as.ary
@@ -1021,58 +1102,91 @@ define output_id
           set $arylen = $ary->as.heap.len
         end
         set $result = $aryptr[($serial % ID_ENTRY_UNIT) * ID_ENTRY_SIZE + $t]
-        output_string $result
+        if $result != RUBY_Qnil
+          print_string $result
+        else
+          echo undef
+        end
       end
     end
   end
 end
 
+define print_pathobj
+  set $flags = ((struct RBasic*)($arg0))->flags
+  if ($flags & RUBY_T_MASK) == RUBY_T_STRING
+    print_string $arg0
+  end
+  if ($flags & RUBY_T_MASK) == RUBY_T_ARRAY
+    if $flags & RUBY_FL_USER1
+      set $str = ((struct RArray*)($arg0))->as.ary[0]
+    else
+      set $str = ((struct RArray*)($arg0))->as.heap.ptr[0]
+    end
+    print_string $str
+  end
+end
+
 define rb_ps_thread
   set $ps_thread = (struct RTypedData*)$arg0
   set $ps_thread_th = (rb_thread_t*)$ps_thread->data
   printf "* #<Thread:%p rb_thread_t:%p native_thread:%p>\n", \
     $ps_thread, $ps_thread_th, $ps_thread_th->thread_id
-  set $cfp = $ps_thread_th->cfp
-  set $cfpend = (rb_control_frame_t *)($ps_thread_th->stack + $ps_thread_th->stack_size)-1
+  set $cfp = $ps_thread_th->ec->cfp
+  set $cfpend = (rb_control_frame_t *)($ps_thread_th->ec->vm_stack + $ps_thread_th->ec->vm_stack_size)-1
   while $cfp < $cfpend
     if $cfp->iseq
+      if !((VALUE)$cfp->iseq & RUBY_IMMEDIATE_MASK) && (((imemo_ifunc << RUBY_FL_USHIFT) | RUBY_T_IMEMO)==$cfp->iseq->flags & ((RUBY_IMEMO_MASK << RUBY_FL_USHIFT) | RUBY_T_MASK))
+        printf "%d:ifunc ", $cfpend-$cfp
+        set print symbol-filename on
+        output/a $cfp->iseq.body
+        set print symbol-filename off
+        printf "\n"
+      else
       if $cfp->pc
         set $location = $cfp->iseq->body->location
-        output_string $location.path
+        printf "%d:", $cfpend-$cfp
+        print_pathobj $location.pathobj
         printf ":"
         print_lineno $cfp
         printf ":in `"
-        output_string $location.label
+        print_string $location.label
         printf "'\n"
       else
-        printf "???.rb:???:in `???'\n"
+        printf "%d: ???.rb:???:in `???'\n", $cfpend-$cfp
+      end
       end
     else
-      # if ($cfp->flag & VM_FRAME_MAGIC_MASK) == VM_FRAME_MAGIC_CFUNC
-      if ($cfp->flag & 255) == 0x61
-        #define VM_ENVVAL_BLOCK_PTR_FLAG 0x02
-        #define VM_EP_PREV_EP(ep)   ((VALUE *)GC_GUARDED_PTR_REF((ep)[0]))
-        set $ep = $cfp->ep
-        set $me = NULL
-        while ($ep[0] & 0x02) != 0
-          check_method_entry $ep[-1] 0
-          if $me != NULL
+      # if VM_FRAME_TYPE($cfp->flag) == VM_FRAME_MAGIC_CFUNC
+      set $ep = $cfp->ep
+      if ($ep[0] & 0xffff0001) == 0x55550001
+        #define VM_ENV_FLAG_LOCAL 0x02
+        #define VM_ENV_PREV_EP(ep)   GC_GUARDED_PTR_REF(ep[VM_ENV_DATA_INDEX_SPECVAL])
+        set $me = 0
+        set $env_specval = $ep[-1]
+        set $env_me_cref = $ep[-2]
+        while ($env_specval & 0x02) != 0
+          check_method_entry $env_me_cref
+          if $me != 0
             loop_break
           end
           set $ep = $ep[0]
+          set $env_specval = $ep[-1]
+          set $env_me_cref = $ep[-2]
         end
-        if $me == NULL
-          check_method_entry $ep[-1] 1
+        if $me == 0
+          check_method_entry $env_me_cref
         end
+        printf "%d:", $cfpend-$cfp
         set print symbol-filename on
         output/a $me->def->body.cfunc.func
         set print symbol-filename off
         set $mid = $me->def->original_id
         printf ":in `"
-        output_id $mid
+        print_id $mid
         printf "'\n"
       else
-        printf "unknown_frame:???:in `???'\n"
+        printf "%d:unknown_frame:???:in `???'\n", $cfpend-$cfp
       end
     end
     set $cfp = $cfp + 1
@@ -1080,7 +1194,7 @@ define rb_ps_thread
 end
 
 define rb_count_objects
-  set $objspace = ruby_current_vm->objspace
+  set $objspace = ruby_current_vm_ptr->objspace
   set $counts_00 = 0
   set $counts_01 = 0
   set $counts_02 = 0
@@ -1165,7 +1279,7 @@ document rb_count_objects
   Counts all objects grouped by type.
 end
 
-# Details: https://bugs.ruby-lang.org/projects/ruby-trunk/wiki/MachineInstructionsTraceWithGDB
+# Details: https://bugs.ruby-lang.org/projects/ruby-master/wiki/MachineInstructionsTraceWithGDB
 define trace_machine_instructions
   set logging on
   set height 0
@@ -1204,3 +1318,33 @@ define dump_node
                         ((struct RString*)$str)->as.heap.ptr : \
                         ((struct RString*)$str)->as.ary)
 end
+
+define print_flags
+  printf "RUBY_FL_WB_PROTECTED: %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_WB_PROTECTED ? "1" : "0"
+  printf "RUBY_FL_PROMOTED0   : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_PROMOTED0 ? "1" : "0"
+  printf "RUBY_FL_PROMOTED1   : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_PROMOTED1 ? "1" : "0"
+  printf "RUBY_FL_FINALIZE    : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_FINALIZE ? "1" : "0"
+  printf "RUBY_FL_SHAREABLE   : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_SHAREABLE ? "1" : "0"
+  printf "RUBY_FL_EXIVAR      : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_EXIVAR ? "1" : "0"
+  printf "RUBY_FL_FREEZE      : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_FREEZE ? "1" : "0"
+
+  printf "RUBY_FL_USER0       : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER0 ? "1" : "0"
+  printf "RUBY_FL_USER1       : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER1 ? "1" : "0"
+  printf "RUBY_FL_USER2       : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER2 ? "1" : "0"
+  printf "RUBY_FL_USER3       : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER3 ? "1" : "0"
+  printf "RUBY_FL_USER4       : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER4 ? "1" : "0"
+  printf "RUBY_FL_USER5       : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER5 ? "1" : "0"
+  printf "RUBY_FL_USER6       : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER6 ? "1" : "0"
+  printf "RUBY_FL_USER7       : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER7 ? "1" : "0"
+  printf "RUBY_FL_USER8       : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER8 ? "1" : "0"
+  printf "RUBY_FL_USER9       : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER9 ? "1" : "0"
+  printf "RUBY_FL_USER10      : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER10 ? "1" : "0"
+  printf "RUBY_FL_USER11      : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER11 ? "1" : "0"
+  printf "RUBY_FL_USER12      : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER12 ? "1" : "0"
+  printf "RUBY_FL_USER13      : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER13 ? "1" : "0"
+  printf "RUBY_FL_USER14      : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER14 ? "1" : "0"
+  printf "RUBY_FL_USER15      : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER15 ? "1" : "0"
+  printf "RUBY_FL_USER16      : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER16 ? "1" : "0"
+  printf "RUBY_FL_USER17      : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER17 ? "1" : "0"
+  printf "RUBY_FL_USER18      : %s\n", ((struct RBasic*)($arg0))->flags & RUBY_FL_USER18 ? "1" : "0"
+end
diff --git a/.git-blame-ignore-revs b/.git-blame-ignore-revs
new file mode 100644
index 0000000000..6c5eac5a0f
--- /dev/null
+++ b/.git-blame-ignore-revs
@@ -0,0 +1,23 @@
+# This is a file used by GitHub to ignore the following commits on `git blame`.
+#
+# You can also do the same thing in your local repository with:
+# $ git config --local blame.ignoreRevsFile .git-blame-ignore-revs
+
+# Expand tabs
+5b21e94bebed90180d8ff63dad03b8b948361089
+
+# Enable Style/StringLiterals cop for RubyGems/Bundler
+d7ffd3fea402239b16833cc434404a7af82d44f3
+
+# [ruby/digest] Revert tab-expansion in external files
+48b09aae7ec5632209229dcc294dd0d75a93a17f
+8a65cf3b61c60e4cb886f59a73ff6db44364bfa9
+39dc9f9093901d40d2998653948d5da38b18ee2c
+
+# [ruby/io-nonblock] Revert tab expansion
+f28287d34c03f472ffe90ea262bdde9affd4b965
+0d842fecb4f75ab3b1d4097ebdb8e88f51558041
+4ba2c66761d6a293abdfba409241d31063cefd62
+
+# Make benchmark indentation consistent
+fc4acf8cae82e5196186d3278d831f2438479d91
diff --git a/.gitattributes b/.gitattributes
index d9785fad00..d0c2d266b4 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -1,5 +1,8 @@
 *.gemspec diff=ruby
 *.rb diff=ruby
+bin svn-properties=svn:ignore=ruby
 bin/* diff=ruby
 tool/update-deps diff=ruby
 tool/make-snapshot diff=ruby
+tool/format-release diff=ruby
+tool/leaked-globals diff=ruby
diff --git a/.github/SECURITY.md b/.github/SECURITY.md
new file mode 100644
index 0000000000..56baa29942
--- /dev/null
+++ b/.github/SECURITY.md
@@ -0,0 +1,9 @@
+# Security Policy
+
+## Supported Versions
+
+See <https://www.ruby-lang.org/en/downloads/branches/>.
+
+## Reporting a Vulnerability
+
+See <https://www.ruby-lang.org/en/security/>.
diff --git a/.github/codeql/codeql-config.yml b/.github/codeql/codeql-config.yml
new file mode 100644
index 0000000000..91f82b842b
--- /dev/null
+++ b/.github/codeql/codeql-config.yml
@@ -0,0 +1,3 @@
+name: "CodeQL config for the Ruby language"
+
+languages: cpp
diff --git a/.github/dependabot.yml b/.github/dependabot.yml
new file mode 100644
index 0000000000..bc63aca35b
--- /dev/null
+++ b/.github/dependabot.yml
@@ -0,0 +1,6 @@
+version: 2
+updates:
+  - package-ecosystem: 'github-actions'
+    directory: '/'
+    schedule:
+      interval: 'monthly'
diff --git a/.github/workflows/baseruby.yml b/.github/workflows/baseruby.yml
new file mode 100644
index 0000000000..ebaafe3bf0
--- /dev/null
+++ b/.github/workflows/baseruby.yml
@@ -0,0 +1,80 @@
+name: BASERUBY Check
+
+on:
+  push:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  pull_request:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+
+concurrency:
+  group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
+  cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
+
+permissions:
+  contents: read
+
+jobs:
+  baseruby:
+    name: BASERUBY
+    runs-on: ubuntu-22.04
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    strategy:
+      matrix:
+        ruby:
+          - ruby-2.2
+#         - ruby-2.3
+#         - ruby-2.4
+#         - ruby-2.5
+#         - ruby-2.6
+#         - ruby-2.7
+          - ruby-3.0
+          - ruby-3.1
+
+    steps:
+      - 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@13e7a03dc3ac6c3798f4570bfead2aed4d96abfb # v1.244.0
+        with:
+          ruby-version: ${{ matrix.ruby }}
+          bundler: none
+      - run: echo "GNUMAKEFLAGS=-j$((1 + $(nproc --all)))" >> $GITHUB_ENV
+      - run: sudo apt-get install build-essential autoconf bison libyaml-dev
+      - run: ./autogen.sh
+      - run: ./configure --disable-install-doc
+      - run: make common-srcs
+      - run: make incs
+      - run: make all
+      - run: make test
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
+        with:
+          payload: |
+            {
+              "ci": "GitHub Actions",
+              "env": "${{ github.workflow }} / BASERUBY @ ${{ matrix.ruby }}",
+              "url": "https://github.com/${{ 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/bundled_gems.yml b/.github/workflows/bundled_gems.yml
new file mode 100644
index 0000000000..070c0fa1dd
--- /dev/null
+++ b/.github/workflows/bundled_gems.yml
@@ -0,0 +1,166 @@
+name: bundled_gems
+
+on:
+  push:
+    branches: [ "master" ]
+    paths:
+      - '.github/workflows/bundled_gems.yml'
+      - 'gems/bundled_gems'
+  pull_request:
+    branches: [ "master" ]
+    paths:
+      - '.github/workflows/bundled_gems.yml'
+      - 'gems/bundled_gems'
+  merge_group:
+    branches: [ "master" ]
+    paths:
+      - '.github/workflows/bundled_gems.yml'
+      - 'gems/bundled_gems'
+  schedule:
+    - cron: '45 6 * * *'
+  workflow_dispatch:
+
+permissions:  # added using https://github.com/step-security/secure-workflows
+  contents: read
+
+jobs:
+  update:
+    permissions:
+      contents: write  # for Git to git push
+    if: ${{ github.event_name != 'schedule' || github.repository == 'ruby/ruby' }}
+    name: update ${{ github.workflow }}
+    runs-on: ubuntu-latest
+    steps:
+      - name: git config
+        run: |
+          git config --global advice.detachedHead 0
+          git config --global init.defaultBranch garbage
+
+      - name: Set ENV
+        run: |
+          echo "GNUMAKEFLAGS=-j$((1 + $(nproc --all)))" >> $GITHUB_ENV
+          echo "TODAY=$(date +%F)" >> $GITHUB_ENV
+
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        with:
+          path: .downloaded-cache
+          key: downloaded-cache-${{ github.sha }}
+          restore-keys: |
+            downloaded-cache
+
+      - name: Download previous gems list
+        run: |
+          data=bundled_gems.json
+          mkdir -p .downloaded-cache
+          ln -s .downloaded-cache/$data .
+          curl -O -R -z ./$data https://stdgems.org/$data
+
+      - name: Update bundled gems list
+        run: |
+          ruby -i~ tool/update-bundled_gems.rb gems/bundled_gems
+
+      - 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[bundled].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
+            changed, added = changed.partition {|g, _| last[g]}
+            news.sub!(/^\*( +)The following #{type} gems? are updated\.\n+\K(?: \1\*( +).*\n)*/) do
+              mark = "#{$1} *#{$2}"
+              changed.map {|g, v|"#{mark}#{g} #{v}\n"}.join("")
+            end or next
+            news.sub!(/^\*( +)The following default gems are now bundled gems\.\n+\K(?: \1\*( +).*\n)*/) do
+              mark = "#{$1} *#{$2}"
+              added.map {|g, v|"#{mark}#{g} #{v}\n"}.join("")
+            end or next unless added.empty?
+            File.write("NEWS.md", news)
+          end
+        shell: ruby {0}
+
+      - name: Check diffs
+        id: diff
+        run: |
+          git add -- NEWS.md
+          git diff --no-ext-diff --ignore-submodules --quiet -- gems/bundled_gems
+        continue-on-error: true
+
+      - name: Install libraries
+        run: |
+          set -x
+          sudo apt-get update -q || :
+          sudo apt-get install --no-install-recommends -q -y build-essential libssl-dev libyaml-dev libreadline6-dev zlib1g-dev libncurses5-dev libffi-dev bison autoconf ruby
+        if: ${{ steps.diff.outcome == 'failure' }}
+
+      - name: Build
+        run: |
+          ./autogen.sh
+          ./configure -C --disable-install-doc
+          make
+        if: ${{ steps.diff.outcome == 'failure' }}
+
+      - name: Prepare bundled gems
+        run: |
+          make -s prepare-gems
+        if: ${{ steps.diff.outcome == 'failure' }}
+
+      - name: Test bundled gems
+        run: |
+          make -s test-bundled-gems
+          git add -- gems/bundled_gems
+        timeout-minutes: 30
+        env:
+          RUBY_TESTOPTS: "-q --tty=no"
+          TEST_BUNDLED_GEMS_ALLOW_FAILURES: ""
+        if: ${{ steps.diff.outcome == 'failure' }}
+
+      - name: Show diffs
+        id: show
+        run: |
+          git diff --cached --color --no-ext-diff --ignore-submodules --exit-code --
+        continue-on-error: true
+
+      - name: Commit
+        run: |
+          git pull --ff-only origin ${GITHUB_REF#refs/heads/}
+          message="Update bundled gems list at "
+          if [ ${{ steps.diff.outcome }} = success ]; then
+            git commit --message="${message}${GITHUB_SHA:0:30} [ci skip]"
+          else
+            git commit --message="${message}${TODAY}"
+          fi
+          git push origin ${GITHUB_REF#refs/heads/}
+        env:
+          EMAIL: svn-admin@ruby-lang.org
+          GIT_AUTHOR_NAME: git
+          GIT_COMMITTER_NAME: git
+        if: ${{ github.repository == 'ruby/ruby' && !startsWith(github.event_name, 'pull') && steps.show.outcome == 'failure' }}
+
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
+        with:
+          payload: |
+            {
+              "ci": "GitHub Actions",
+              "env": "${{ 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
new file mode 100644
index 0000000000..79b2916feb
--- /dev/null
+++ b/.github/workflows/check_dependencies.yml
@@ -0,0 +1,78 @@
+name: Check Dependencies
+on:
+  push:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  pull_request:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+
+concurrency:
+  group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
+  cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
+
+permissions:
+  contents: read
+
+jobs:
+  update-deps:
+    strategy:
+      matrix:
+        os: [ubuntu-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') }}
+    steps:
+      - name: Install libraries
+        run: |
+          set -x
+          sudo apt-get update -q || :
+          sudo apt-get install --no-install-recommends -q -y build-essential libssl-dev libyaml-dev libreadline6-dev zlib1g-dev libncurses5-dev libffi-dev bison autoconf ruby
+        if: ${{ contains(matrix.os, 'ubuntu') }}
+      - name: Install libraries
+        run: |
+          brew install gmp libffi openssl@1.1 zlib autoconf automake libtool readline
+        if: ${{ contains(matrix.os, 'macos') }}
+      - name: git config
+        run: |
+          git config --global advice.detachedHead 0
+          git config --global init.defaultBranch garbage
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        with:
+          path: .downloaded-cache
+          key: downloaded-cache
+      - run: ./autogen.sh
+      - name: Run configure
+        run: ./configure -C --disable-install-doc --disable-rubygems --with-gcc 'optflags=-O0' 'debugflags=-save-temps=obj -g'
+      - run: make all golf
+      - run: ruby tool/update-deps --fix
+      - run: git diff --no-ext-diff --ignore-submodules --exit-code
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
+        with:
+          payload: |
+            {
+              "ci": "GitHub Actions",
+              "env": "${{ matrix.os }} / Dependencies need to 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/codeql-analysis.yml b/.github/workflows/codeql-analysis.yml
new file mode 100644
index 0000000000..8dba76fbe2
--- /dev/null
+++ b/.github/workflows/codeql-analysis.yml
@@ -0,0 +1,75 @@
+name: "Code scanning - action"
+
+on:
+  # push:
+  #   paths-ignore:
+  #     - 'doc/**'
+  #     - '**/man'
+  #     - '**.md'
+  #     - '**.rdoc'
+  #     - '**/.document'
+  # pull_request:
+  #   paths-ignore:
+  #     - 'doc/**'
+  #     - '**/man'
+  #     - '**.md'
+  #     - '**.rdoc'
+  #     - '**/.document'
+  schedule:
+    - cron: '0 12 * * *'
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
+  cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
+
+permissions:  # added using https://github.com/step-security/secure-workflows
+  contents: read
+
+jobs:
+  CodeQL-Build:
+
+    # CodeQL runs on ubuntu-latest and windows-latest
+    permissions:
+      actions: read  # for github/codeql-action/init to get workflow details
+      contents: read  # for actions/checkout to fetch code
+      security-events: write  # for github/codeql-action/autobuild to send a status report
+    runs-on: ubuntu-latest
+    # CodeQL fails to run pull requests from dependabot due to missing write access to upload results.
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') && github.event.head_commit.pusher.name != 'dependabot[bot]' }}
+
+    env:
+      enable_install_doc: no
+
+    steps:
+    - name: Install libraries
+      run: |
+        set -x
+        sudo apt-get update -q || :
+        sudo apt-get install --no-install-recommends -q -y build-essential libssl-dev libyaml-dev libreadline6-dev zlib1g-dev libncurses5-dev libffi-dev bison autoconf ruby
+
+    - name: Checkout repository
+      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+
+    - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+      with:
+        path: .downloaded-cache
+        key: downloaded-cache
+
+    - name: Remove an obsolete rubygems vendored file
+      run: sudo rm /usr/lib/ruby/vendor_ruby/rubygems/defaults/operating_system.rb
+
+    - name: Initialize CodeQL
+      uses: github/codeql-action/init@959cbb7472c4d4ad70cdfe6f4976053fe48ab394 # v2.1.37
+      with:
+        config-file: ./.github/codeql/codeql-config.yml
+        trap-caching: false
+
+    - name: Set ENV
+      run: echo "GNUMAKEFLAGS=-j$((1 + $(nproc --all)))" >> $GITHUB_ENV
+
+    - name: Autobuild
+      uses: github/codeql-action/autobuild@959cbb7472c4d4ad70cdfe6f4976053fe48ab394 # v2.1.37
+
+    - name: Perform CodeQL Analysis
+      uses: github/codeql-action/analyze@959cbb7472c4d4ad70cdfe6f4976053fe48ab394 # v2.1.37
diff --git a/.github/workflows/compilers.yml b/.github/workflows/compilers.yml
new file mode 100644
index 0000000000..caf12cc0f4
--- /dev/null
+++ b/.github/workflows/compilers.yml
@@ -0,0 +1,281 @@
+name: Compilations
+
+on:
+  push:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  pull_request:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.rdoc'
+      - '**/.document'
+
+concurrency:
+  group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
+  cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
+
+# GitHub actions does not support YAML anchors.  This creative use of
+# environment variables (plus the "echo $GITHUB_ENV" hack) is to reroute that
+# restriction.
+env:
+  default_cc: clang-15
+  append_cc: ''
+
+  # -O1 is faster than -O3 in our tests... Majority of time are consumed trying
+  # to optimize binaries.  Also GitHub Actions run on relatively modern CPUs
+  # compared to, say, GCC 4 or Clang 3.  We don't specify `-march=native`
+  # because compilers tend not understand what the CPU is.
+  optflags: '-O1'
+
+  # -g0 disables backtraces when SEGV.  Do not set that.
+  debugflags: '-ggdb3'
+
+  default_configure: >-
+    --enable-debug-env
+    --disable-install-doc
+    --with-ext=-test-/cxxanyargs,+
+  append_configure: >-
+    --without-valgrind
+    --without-jemalloc
+    --without-gmp
+
+  UPDATE_UNICODE: >-
+    UNICODE_FILES=.
+    UNICODE_PROPERTY_FILES=.
+    UNICODE_AUXILIARY_FILES=.
+    UNICODE_EMOJI_FILES=.
+  CONFIGURE_TTY: never
+  GITPULLOPTIONS: --no-tags origin ${{github.ref}}
+  RUBY_DEBUG: ci rgengc
+  RUBY_TESTOPTS: >-
+    -q
+    --color=always
+    --tty=no
+
+permissions:
+  contents: read
+
+jobs:
+  compile:
+    strategy:
+      fail-fast: false
+      matrix:
+        env:
+          - {}
+        entry:
+          - { name: gcc-12,    env: { default_cc: gcc-12 } }
+          - { name: gcc-11,    env: { default_cc: gcc-11 } }
+          - { name: gcc-10,    env: { default_cc: gcc-10 } }
+          - { name: gcc-9,     env: { default_cc: gcc-9 } }
+          - { name: gcc-8,     env: { default_cc: gcc-8 } }
+          - { name: gcc-7,     env: { default_cc: gcc-7 } }
+          - name: 'gcc-13 LTO'
+            container: gcc-13
+            env:
+              default_cc: 'gcc-13 -flto=auto -ffat-lto-objects -Werror=lto-type-mismatch'
+              optflags: '-O2'
+            shared: disable
+            # check: true
+          - { name: clang-16,  env: { default_cc: clang-16 } }
+          - { name: clang-15,  env: { default_cc: clang-15 } }
+          - { name: clang-14,  env: { default_cc: clang-14 } }
+          - { name: clang-13,  env: { default_cc: clang-13 } }
+          - { name: clang-12,  env: { default_cc: clang-12 } }
+          - { name: clang-11,  env: { default_cc: clang-11 } }
+          - { name: clang-10,  env: { default_cc: clang-10 } }
+          # llvm-objcopy<=9 doesn't have --wildcard. It compiles, but leaves Rust symbols in libyjit.o.
+          - { name: clang-9,   env: { default_cc: clang-9,   append_configure: '--disable-yjit' } }
+          - { name: clang-8,   env: { default_cc: clang-8,   append_configure: '--disable-yjit' } }
+          - { name: clang-7,   env: { default_cc: clang-7,   append_configure: '--disable-yjit' } }
+          - { name: clang-6.0, env: { default_cc: clang-6.0, append_configure: '--disable-yjit' } }
+          - name: 'clang-16 LTO'
+            container: clang-16
+            env:
+              default_cc: 'clang-16 -flto=auto'
+              optflags: '-O2'
+            shared: disable
+            # check: true
+
+#         - { name: aarch64-linux-gnu,     crosshost: aarch64-linux-gnu, container: crossbuild-essential-arm64 }
+#         - { name: arm-linux-gnueabi,     crosshost: arm-linux-gnueabi }
+#         - { name: arm-linux-gnueabihf,   crosshost: arm-linux-gnueabihf }
+#         - { name: i686-w64-mingw32,      crosshost: i686-w64-mingw32 }
+#         - { name: powerpc-linux-gnu,     crosshost: powerpc-linux-gnu }
+#         - { name: powerpc64le-linux-gnu, crosshost: powerpc64le-linux-gnu, container: crossbuild-essential-ppc64el }
+#         - { name: s390x-linux-gnu,       crosshost: s390x-linux-gnu, container: crossbuild-essential-s390x }
+#         - { name: x86_64-w64-mingw32,    crosshost: x86_64-w64-mingw32, container: mingw-w64 }
+
+          # -Wno-strict-prototypes is necessary with current clang-15 since
+          # older autoconf generate functions without prototype and -pedantic
+          # now implies strict-prototypes. Disabling the error but leaving the
+          # warning generates a lot of noise from use of ANYARGS in
+          # rb_define_method() and friends.
+          # See: https://github.com/llvm/llvm-project/commit/11da1b53d8cd3507959022cd790d5a7ad4573d94
+          - { name: c99,   env: { append_cc: '-std=c99   -Werror=pedantic -pedantic-errors -Wno-strict-prototypes' } }
+#         - { name: c11,   env: { append_cc: '-std=c11   -Werror=pedantic -pedantic-errors -Wno-strict-prototypes' } }
+#         - { name: c17,   env: { append_cc: '-std=c17   -Werror=pedantic -pedantic-errors -Wno-strict-prototypes' } }
+          - { name: c2x,   env: { append_cc: '-std=c2x   -Werror=pedantic -pedantic-errors -Wno-strict-prototypes' } }
+          - { name: c++98, env: { CXXFLAGS: '-std=c++98 -Werror=pedantic -pedantic-errors -Wno-c++11-long-long' } }
+#         - { name: c++11, env: { CXXFLAGS: '-std=c++11 -Werror=pedantic -pedantic-errors -Wno-c++11-long-long' } }
+#         - { name: c++14, env: { CXXFLAGS: '-std=c++14 -Werror=pedantic -pedantic-errors -Wno-c++11-long-long' } }
+#         - { name: c++17, env: { CXXFLAGS: '-std=c++17 -Werror=pedantic -pedantic-errors -Wno-c++11-long-long' } }
+          - { name: c++2a, env: { CXXFLAGS: '-std=c++2a -Werror=pedantic -pedantic-errors -Wno-c++11-long-long' } }
+
+          - { name: '-O0', env: { optflags: '-O0 -march=x86-64 -mtune=generic' } }
+#         - { name: '-O3', env: { optflags: '-O3 -march=x86-64 -mtune=generic' }, check: true }
+
+          - { name: gmp,                  env: { append_configure: '--with-gmp' } }
+          - { name: jemalloc,             env: { append_configure: '--with-jemalloc' } }
+          - { name: valgrind,             env: { append_configure: '--with-valgrind' } }
+          - { name: 'coroutine=ucontext', env: { append_configure: '--with-coroutine=ucontext' } }
+          - { name: 'coroutine=pthread',  env: { append_configure: '--with-coroutine=pthread' } }
+          - { name: disable-jit-support,  env: { append_configure: '--disable-jit-support' } }
+          - { name: disable-dln,          env: { append_configure: '--disable-dln' } }
+          - { name: enable-mkmf-verbose,  env: { append_configure: '--enable-mkmf-verbose' } }
+          - { name: disable-rubygems,     env: { append_configure: '--disable-rubygems' } }
+          - { name: RUBY_DEVEL,           env: { append_configure: '--enable-devel' } }
+
+          - { name: OPT_THREADED_CODE=1,            env: { cppflags: '-DOPT_THREADED_CODE=1' } }
+          - { name: OPT_THREADED_CODE=2,            env: { cppflags: '-DOPT_THREADED_CODE=2' } }
+          - { name: OPT_THREADED_CODE=3,            env: { cppflags: '-DOPT_THREADED_CODE=3' } }
+
+          - { name: NDEBUG,                         env: { cppflags: '-DNDEBUG' } }
+          - { name: RUBY_DEBUG,                     env: { cppflags: '-DRUBY_DEBUG' } }
+#         - { name: ARRAY_DEBUG,                    env: { cppflags: '-DARRAY_DEBUG' } }
+#         - { name: BIGNUM_DEBUG,                   env: { cppflags: '-DBIGNUM_DEBUG' } }
+#         - { name: CCAN_LIST_DEBUG,                env: { cppflags: '-DCCAN_LIST_DEBUG' } }
+#         - { name: CPDEBUG=-1,                     env: { cppflags: '-DCPDEBUG=-1' } }
+#         - { name: ENC_DEBUG,                      env: { cppflags: '-DENC_DEBUG' } }
+#         - { name: GC_DEBUG,                       env: { cppflags: '-DGC_DEBUG' } }
+#         - { name: HASH_DEBUG,                     env: { cppflags: '-DHASH_DEBUG' } }
+#         - { name: ID_TABLE_DEBUG,                 env: { cppflags: '-DID_TABLE_DEBUG' } }
+#         - { name: RGENGC_DEBUG=-1,                env: { cppflags: '-DRGENGC_DEBUG=-1' } }
+#         - { name: SYMBOL_DEBUG,                   env: { cppflags: '-DSYMBOL_DEBUG' } }
+
+#         - { name: RGENGC_CHECK_MODE,              env: { cppflags: '-DRGENGC_CHECK_MODE' } }
+#         - { name: TRANSIENT_HEAP_CHECK_MODE,      env: { cppflags: '-DTRANSIENT_HEAP_CHECK_MODE' } }
+#         - { name: VM_CHECK_MODE,                  env: { cppflags: '-DVM_CHECK_MODE' } }
+
+          - { name: USE_EMBED_CI=0,                 env: { cppflags: '-DUSE_EMBED_CI=0' } }
+          - name: USE_FLONUM=0,
+            env:
+              cppflags: '-DUSE_FLONUM=0'
+              # yjit requires FLONUM for the pointer tagging scheme
+              append_configure: '--disable-yjit'
+#         - { name: USE_GC_MALLOC_OBJ_INFO_DETAILS, env: { cppflags: '-DUSE_GC_MALLOC_OBJ_INFO_DETAILS' } }
+          - { name: USE_LAZY_LOAD,                  env: { cppflags: '-DUSE_LAZY_LOAD' } }
+#         - { name: USE_RINCGC=0,                   env: { cppflags: '-DUSE_RINCGC=0' } }
+#         - { name: USE_SYMBOL_GC=0,                env: { cppflags: '-DUSE_SYMBOL_GC=0' } }
+#         - { name: USE_THREAD_CACHE=0,             env: { cppflags: '-DUSE_THREAD_CACHE=0' } }
+#         - { name: USE_TRANSIENT_HEAP=0,           env: { cppflags: '-DUSE_TRANSIENT_HEAP=0' } }
+#         - { name: USE_RUBY_DEBUG_LOG=1,           env: { cppflags: '-DUSE_RUBY_DEBUG_LOG=1' } }
+          - { name: USE_RVARGC=0,                   env: { cppflags: '-DUSE_RVARGC=0' } }
+#         - { name: USE_RVARGC=1,                   env: { cppflags: '-DUSE_RVARGC=1' } }
+#         - { name: USE_DEBUG_COUNTER,              env: { cppflags: '-DUSE_DEBUG_COUNTER=1', RUBY_DEBUG_COUNTER_DISABLE: '1' } }
+
+          - { name: DEBUG_FIND_TIME_NUMGUESS,       env: { cppflags: '-DDEBUG_FIND_TIME_NUMGUESS' } }
+          - { name: DEBUG_INTEGER_PACK,             env: { cppflags: '-DDEBUG_INTEGER_PACK' } }
+#         - { name: ENABLE_PATH_CHECK,              env: { cppflags: '-DENABLE_PATH_CHECK' } }
+
+          - { name: GC_DEBUG_STRESS_TO_CLASS,       env: { cppflags: '-DGC_DEBUG_STRESS_TO_CLASS' } }
+#         - { name: GC_ENABLE_LAZY_SWEEP=0,         env: { cppflags: '-DGC_ENABLE_LAZY_SWEEP=0' } }
+#         - { name: GC_PROFILE_DETAIL_MEMOTY,       env: { cppflags: '-DGC_PROFILE_DETAIL_MEMOTY' } }
+#         - { name: GC_PROFILE_MORE_DETAIL,         env: { cppflags: '-DGC_PROFILE_MORE_DETAIL' } }
+
+#         - { name: CALC_EXACT_MALLOC_SIZE,         env: { cppflags: '-DCALC_EXACT_MALLOC_SIZE' } }
+#         - { name: MALLOC_ALLOCATED_SIZE_CHECK,    env: { cppflags: '-DMALLOC_ALLOCATED_SIZE_CHECK' } }
+
+#         - { name: IBF_ISEQ_ENABLE_LOCAL_BUFFER,   env: { cppflags: '-DIBF_ISEQ_ENABLE_LOCAL_BUFFER' } }
+
+#         - { name: RGENGC_ESTIMATE_OLDMALLOC,      env: { cppflags: '-DRGENGC_ESTIMATE_OLDMALLOC' } }
+#         - { name: RGENGC_FORCE_MAJOR_GC,          env: { cppflags: '-DRGENGC_FORCE_MAJOR_GC' } }
+#         - { name: RGENGC_OBJ_INFO,                env: { cppflags: '-DRGENGC_OBJ_INFO' } }
+#         - { name: RGENGC_OLD_NEWOBJ_CHECK,        env: { cppflags: '-DRGENGC_OLD_NEWOBJ_CHECK' } }
+#         - { name: RGENGC_PROFILE,                 env: { cppflags: '-DRGENGC_PROFILE' } }
+
+#         - { name: VM_DEBUG_BP_CHECK,              env: { cppflags: '-DVM_DEBUG_BP_CHECK' } }
+#         - { name: VM_DEBUG_VERIFY_METHOD_CACHE,   env: { cppflags: '-DVM_DEBUG_VERIFY_METHOD_CACHE' } }
+
+          - { name: MJIT_FORCE_ENABLE,              env: { cppflags: '-DMJIT_FORCE_ENABLE' } }
+          - { name: YJIT_FORCE_ENABLE,              env: { cppflags: '-DYJIT_FORCE_ENABLE' } }
+
+    name: ${{ matrix.entry.name }}
+    runs-on: ubuntu-latest
+    container:
+      image: ghcr.io/ruby/ruby-ci-image:${{ matrix.entry.container || matrix.entry.env.default_cc || 'clang-15' }}
+      options: --user root
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    env: ${{ matrix.entry.env || matrix.env }}
+    steps:
+      - run: id
+        working-directory:
+      - run: mkdir build
+        working-directory:
+      - name: setenv
+        run: |
+          echo "GNUMAKEFLAGS=-sj$((1 + $(nproc --all)))" >> $GITHUB_ENV
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          path: src
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        with:
+          path: src/.downloaded-cache
+          key: downloaded-cache
+      - run: ./autogen.sh
+        working-directory: src
+      - name: Run configure
+        run: >
+          ../src/configure -C ${default_configure} ${append_configure}
+          --${{
+            matrix.entry.crosshost && 'host' || 'with-gcc'
+          }}=${{
+            matrix.entry.crosshost || '"${default_cc}${append_cc:+ $append_cc}"'
+          }}
+          --${{ matrix.entry.shared || 'enable' }}-shared
+      - run: make extract-extlibs
+      - run: make incs
+      - run: make showflags
+      - run: make
+      - run: make leaked-globals
+      - run: make test
+      - run: make install
+        if: ${{ matrix.entry.check }}
+      - run: make test-tool
+        if: ${{ matrix.entry.check }}
+      - run: make test-all TESTS='-- ruby -ext-'
+        if: ${{ matrix.entry.check }}
+      - run: make test-spec
+        env:
+          CHECK_LEAKS: true
+        if: ${{ matrix.entry.check }}
+      - run: make test-annocheck
+        if: ${{ matrix.entry.check && endsWith(matrix.entry.name, 'annocheck') }}
+
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
+        with:
+          payload: |
+            {
+              "ci": "GitHub Actions",
+              "env": "${{ github.workflow }} / ${{ matrix.entry.name }}",
+              "url": "https://github.com/${{ 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/macos.yml b/.github/workflows/macos.yml
new file mode 100644
index 0000000000..d8dc58b119
--- /dev/null
+++ b/.github/workflows/macos.yml
@@ -0,0 +1,113 @@
+name: macOS
+on:
+  push:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  pull_request:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+
+concurrency:
+  group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
+  cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
+
+permissions:
+  contents: read
+
+jobs:
+  make:
+    strategy:
+      matrix:
+        test_task: ["check"] # "test-bundler-parallel", "test-bundled-gems"
+        os:
+          - macos-13
+          - macos-14
+          - macos-15
+      fail-fast: false
+    env:
+      GITPULLOPTIONS: --no-tags origin ${{github.ref}}
+    runs-on: ${{ matrix.os }}
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    steps:
+      - run: mkdir build
+        working-directory:
+      - name: git config
+        run: |
+          git config --global advice.detachedHead 0
+          git config --global init.defaultBranch garbage
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          path: src
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        with:
+          path: src/.downloaded-cache
+          key: downloaded-cache
+      - name: Install libraries
+        run: |
+          brew install gmp libffi openssl@1.1 zlib autoconf automake libtool readline bison
+        working-directory: src
+      - name: Set ENV
+        run: |
+          echo "MAKEFLAGS=-j$((1 + $(sysctl -n hw.activecpu)))" >> $GITHUB_ENV
+          echo "PATH="/usr/local/opt/bison/bin:/opt/homebrew/opt/bison/bin:$PATH"" >> $GITHUB_ENV
+      - run: ./autogen.sh
+        working-directory: src
+      - name: Run configure
+        run: ../src/configure -C --disable-install-doc --with-openssl-dir=$(brew --prefix openssl@1.1) --with-readline-dir=$(brew --prefix readline)
+      - run: make incs
+      - run: make prepare-gems
+        if: ${{ matrix.test_task == 'test-bundled-gems' }}
+      - run: make
+      - run: make leaked-globals
+        if: ${{ matrix.test_task == 'check' }}
+      - name: make ${{ matrix.test_task }}
+        run: |
+          make -s ${{ matrix.test_task }} ${TESTS:+TESTS=`echo "$TESTS" | sed 's| |$$/ -n!/|g;s|^|-n!/|;s|$|$$/|'`}
+        timeout-minutes: 40
+        env:
+          RUBY_TESTOPTS: "-q --tty=no"
+          TESTS: ${{ matrix.test_task == 'check' && matrix.skipped_tests || '' }}
+          TEST_BUNDLED_GEMS_ALLOW_FAILURES: ""
+          PRECHECK_BUNDLED_GEMS: "no"
+      - name: make skipped tests
+        run: |
+          make -s test-all TESTS=`echo "$TESTS" | sed 's| |$$/ -n/|g;s|^|-n/|;s|$|$$/|'`
+        env:
+          GNUMAKEFLAGS: ""
+          RUBY_TESTOPTS: "-v --tty=no"
+          TESTS: ${{ matrix.skipped_tests }}
+          PRECHECK_BUNDLED_GEMS: "no"
+        if: ${{ matrix.test_task == 'check' && matrix.skipped_tests != '' }}
+        continue-on-error: ${{ matrix.continue-on-skipped_tests || false }}
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
+        with:
+          payload: |
+            {
+              "ci": "GitHub Actions",
+              "env": "${{ matrix.os }} / ${{ matrix.test_task }}${{ matrix.configure }}",
+              "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
+              "commit": "${{ github.sha }}",
+              "branch": "${{ github.ref_name }}"
+            }
+        env:
+          SLACK_WEBHOOK_URL: ${{ secrets.SIMPLER_ALERTS_URL }} # ruby-lang slack: ruby/simpler-alerts-bot
+        if: ${{ failure() && github.event_name == 'push' }}
+
+defaults:
+  run:
+    working-directory: build
diff --git a/.github/workflows/mingw.yml b/.github/workflows/mingw.yml
new file mode 100644
index 0000000000..0df917d3d8
--- /dev/null
+++ b/.github/workflows/mingw.yml
@@ -0,0 +1,179 @@
+name: MinGW
+on:
+  push:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  pull_request:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+
+concurrency:
+  group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
+  cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
+
+permissions:
+  contents: read
+
+# Notes:
+# Actions console encoding causes issues, see test-all & test-spec steps
+#
+jobs:
+  make:
+    runs-on: windows-2022
+    name: ${{ github.workflow }} (${{ matrix.msystem }})
+    env:
+      MSYSTEM: ${{ matrix.msystem }}
+      MSYS2_ARCH: x86_64
+      CHOST: "x86_64-w64-mingw32"
+      CFLAGS:   "-march=x86-64 -mtune=generic -O3 -pipe"
+      CXXFLAGS: "-march=x86-64 -mtune=generic -O3 -pipe"
+      CPPFLAGS: "-D_FORTIFY_SOURCE=2 -D__USE_MINGW_ANSI_STDIO=1 -DFD_SETSIZE=2048"
+      LDFLAGS:  "-pipe"
+      UPDATE_UNICODE: "UNICODE_FILES=. UNICODE_PROPERTY_FILES=. UNICODE_AUXILIARY_FILES=. UNICODE_EMOJI_FILES=."
+      GITPULLOPTIONS: --no-tags origin ${{github.ref}}
+    strategy:
+      matrix:
+        include:
+          # To mitigate flakiness of MinGW CI, we test only one runtime that newer MSYS2 uses.
+          - msystem: "UCRT64"
+            base_ruby: head
+            test_task: "check"
+            test-all-opts: "--name=!/TestObjSpace#test_reachable_objects_during_iteration/"
+      fail-fast: false
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    steps:
+      - run: mkdir build
+        working-directory:
+      - name: git config
+        run: |
+          git config --global core.autocrlf false
+          git config --global core.eol lf
+          git config --global advice.detachedHead 0
+          git config --global init.defaultBranch garbage
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          path: src
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        with:
+          path: src/.downloaded-cache
+          key: downloaded-cache
+      - name: Set up Ruby & MSYS2
+        uses: ruby/setup-ruby@13e7a03dc3ac6c3798f4570bfead2aed4d96abfb # v1.244.0
+        with:
+          ruby-version: ${{ matrix.base_ruby }}
+      - name: set env
+        run: |
+          echo "GNUMAKEFLAGS=-j$((2 * NUMBER_OF_PROCESSORS))" >> $GITHUB_ENV
+
+      - name: where check
+        run: |
+          # show where
+          mv /c/Windows/System32/libcrypto-1_1-x64.dll /c/Windows/System32/libcrypto-1_1-x64.dll_
+          mv /c/Windows/System32/libssl-1_1-x64.dll    /c/Windows/System32/libssl-1_1-x64.dll_
+          result=true
+          for e in gcc.exe ragel.exe make.exe bison.exe libcrypto-1_1-x64.dll libssl-1_1-x64.dll; do
+            echo '##['group']'$'\033[93m'$e$'\033[m'
+            where $e || result=false
+            echo '##['endgroup']'
+          done
+          $result
+
+      - name: version check
+        run: |
+          # show version
+          result=true
+          for e in gcc ragel make bison "openssl version"; do
+            case "$e" in *" "*) ;; *) e="$e --version";; esac
+            echo '##['group']'$'\033[93m'$e$'\033[m'
+            $e || result=false
+            echo '##['endgroup']'
+          done
+          $result
+
+      - name: autogen
+        run: |
+          ./autogen.sh
+        working-directory: src
+
+      - name: configure
+        run: >
+          ../src/configure --disable-install-doc --prefix=/.
+          --build=$CHOST --host=$CHOST --target=$CHOST
+
+      - name: update
+        run: |
+          make incs
+
+      - name: download gems
+        run: |
+          make update-gems
+
+      - name: make all
+        timeout-minutes: 30
+        run: |
+          make
+
+      - run: make leaked-globals
+
+      - name: make install
+        run: |
+          make DESTDIR=../install install-nodoc
+
+      - name: test
+        timeout-minutes: 5
+        run: |
+          make test
+        if: ${{matrix.test_task == 'check' || matrix.test_task == 'test'}}
+
+      - name: test-all
+        timeout-minutes: 45
+        run: |
+          # Actions uses UTF8, causes test failures, similar to normal OS setup
+          chcp.com 437
+          make ${{ StartsWith(matrix.test_task, 'test/') && matrix.test_task || 'test-all' }}
+        env:
+          RUBY_TESTOPTS: >-
+            --retry --job-status=normal --show-skip --timeout-scale=1.5
+            ${{ matrix.test-all-opts }}
+          BUNDLER_VERSION:
+        if: ${{matrix.test_task == 'check' || matrix.test_task == 'test-all' || StartsWith(matrix.test_task, 'test/')}}
+
+      - name: test-spec
+        timeout-minutes: 10
+        run: |
+          make ${{ StartsWith(matrix.test_task, 'spec/') && matrix.test_task || 'test-spec' }}
+        if: ${{matrix.test_task == 'check' || matrix.test_task == 'test-spec' || StartsWith(matrix.test_task, 'spec/')}}
+
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
+        with:
+          payload: |
+            {
+              "ci": "GitHub Actions",
+              "env": "${{ github.workflow }} ${{ matrix.msystem }} / ${{ matrix.test_task }}",
+              "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
+              "commit": "${{ github.sha }}",
+              "branch": "${{ github.ref_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
+    shell: sh
diff --git a/.github/workflows/mjit-bindgen.yml b/.github/workflows/mjit-bindgen.yml
new file mode 100644
index 0000000000..26f8a1b2aa
--- /dev/null
+++ b/.github/workflows/mjit-bindgen.yml
@@ -0,0 +1,104 @@
+name: MJIT bindgen
+on:
+  push:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  pull_request:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+
+concurrency:
+  group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
+  cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
+
+permissions:
+  contents: read
+
+jobs:
+  make:
+    strategy:
+      matrix:
+        include:
+          - task: mjit-bindgen
+      fail-fast: false
+    runs-on: ubuntu-22.04
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    steps:
+      - run: mkdir build
+        working-directory:
+      - name: Set ENV
+        run: |
+          echo "GNUMAKEFLAGS=-j$((1 + $(nproc --all)))" >> $GITHUB_ENV
+      - name: Install libraries
+        run: |
+          set -x
+          sudo apt-get update -q || :
+          sudo apt-get install --no-install-recommends -q -y \
+          build-essential \
+          libssl-dev libyaml-dev libreadline6-dev \
+          zlib1g-dev libncurses5-dev libffi-dev \
+          libclang1-14 \
+          bison autoconf
+          sudo apt-get install -q -y pkg-config || :
+      - name: Set up Ruby
+        uses: ruby/setup-ruby@13e7a03dc3ac6c3798f4570bfead2aed4d96abfb # v1.244.0
+        with:
+          ruby-version: '3.1'
+      - name: git config
+        run: |
+          git config --global advice.detachedHead 0
+          git config --global init.defaultBranch garbage
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          path: src
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        with:
+          path: src/.downloaded-cache
+          key: downloaded-cache
+      - name: Fixed world writable dirs
+        run: |
+          chmod -v go-w $HOME $HOME/.config
+          sudo chmod -R go-w /usr/share
+          sudo bash -c 'IFS=:; for d in '"$PATH"'; do chmod -v go-w $d; done' || :
+      - run: ./autogen.sh
+        working-directory: src
+      - name: Run configure
+        run: ../src/configure -C --disable-install-doc --prefix=$(pwd)/install --enable-yjit=dev_nodebug
+      - run: make incs
+      - run: make
+      - run: make install
+      - run: make ${{ matrix.task }}
+      - run: git diff --exit-code
+        working-directory: src
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
+        with:
+          payload: |
+            {
+              "ci": "GitHub Actions",
+              "env": "${{ matrix.os }} / ${{ matrix.test_task }}${{ matrix.configure }}",
+              "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
+              "commit": "${{ github.sha }}",
+              "branch": "${{ github.ref_name }}"
+            }
+        env:
+          SLACK_WEBHOOK_URL: ${{ secrets.SIMPLER_ALERTS_URL }} # ruby-lang slack: ruby/simpler-alerts-bot
+        if: ${{ failure() && github.event_name == 'push' }}
+
+defaults:
+  run:
+    working-directory: build
diff --git a/.github/workflows/mjit.yml b/.github/workflows/mjit.yml
new file mode 100644
index 0000000000..6f7181489a
--- /dev/null
+++ b/.github/workflows/mjit.yml
@@ -0,0 +1,113 @@
+name: MJIT
+on:
+  push:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  pull_request:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+      - '**.[1-8]'
+      - '**.ronn'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+      - '**.[1-8]'
+      - '**.ronn'
+
+concurrency:
+  group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
+  cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
+
+permissions:
+  contents: read
+
+jobs:
+  make:
+    strategy:
+      matrix:
+        test_task: [check] # to make job names consistent
+        mjit_opts: [--mjit-wait]
+      fail-fast: false
+    runs-on: ubuntu-latest
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    env:
+      TESTOPTS: '-q --tty=no'
+      RUN_OPTS: '--disable-gems ${{ matrix.mjit_opts }} --mjit-debug=-ggdb3'
+      GITPULLOPTIONS: --no-tags origin ${{github.ref}}
+    steps:
+      - run: mkdir build
+        working-directory:
+      - name: Install libraries
+        run: |
+          set -x
+          sudo apt-get update -q || :
+          sudo apt-get install --no-install-recommends -q -y build-essential libssl-dev libyaml-dev libreadline6-dev zlib1g-dev libncurses5-dev libffi-dev bison autoconf ruby
+      - name: git config
+        run: |
+          git config --global advice.detachedHead 0
+          git config --global init.defaultBranch garbage
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          path: src
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        with:
+          path: src/.downloaded-cache
+          key: downloaded-cache
+      - name: Fixed world writable dirs
+        run: |
+          chmod -v go-w $HOME $HOME/.config
+          sudo chmod -R go-w /usr/share
+          sudo bash -c 'IFS=:; for d in '"$PATH"'; do chmod -v go-w $d; done' || :
+      - name: Set ENV
+        run: |
+          echo "GNUMAKEFLAGS=-j$((1 + $(nproc --all)))" >> $GITHUB_ENV
+      - run: ./autogen.sh
+        working-directory: src
+      - name: Run configure
+        run: ../src/configure -C --disable-install-doc cppflags=-DVM_CHECK_MODE
+      - run: make incs
+      - run: make
+      - run: sudo make -s install
+      - name: Run test
+        run: |
+          unset GNUMAKEFLAGS
+          make -s test RUN_OPTS="$RUN_OPTS"
+        timeout-minutes: 60
+      # - name: Run test-all
+      #   run: |
+      #     ulimit -c unlimited
+      #     make -s test-all RUN_OPTS="$RUN_OPTS"
+      #   timeout-minutes: 60
+      - name: Run test-spec
+        run: |
+          unset GNUMAKEFLAGS
+          make -s test-spec RUN_OPTS="$RUN_OPTS"
+        timeout-minutes: 60
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
+        with:
+          payload: |
+            {
+              "ci": "GitHub Actions",
+              "env": "${{ github.workflow }} / ${{ matrix.test_task }} ${{ matrix.mjit_opts }}",
+              "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
+              "commit": "${{ github.sha }}",
+              "branch": "${{ github.ref_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/publish.yml b/.github/workflows/publish.yml
new file mode 100644
index 0000000000..5d4474d978
--- /dev/null
+++ b/.github/workflows/publish.yml
@@ -0,0 +1,18 @@
+name: Start release workflow
+on:
+  push:
+    tags:
+      - '*'
+
+jobs:
+  notify:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Build release package
+        run: |
+          curl -L -X POST \
+            -H "Authorization: Bearer ${{ secrets.MATZBOT_GITHUB_WORKFLOW_TOKEN }}" \
+            -H "Accept: application/vnd.github+json" \
+            -H "X-GitHub-Api-Version: 2022-11-28" \
+            https://api.github.com/repos/ruby/actions/dispatches \
+            -d '{"event_type": "${{ github.ref }}"}'
diff --git a/.github/workflows/scorecards.yml b/.github/workflows/scorecards.yml
new file mode 100644
index 0000000000..c12a95362d
--- /dev/null
+++ b/.github/workflows/scorecards.yml
@@ -0,0 +1,72 @@
+# This workflow uses actions that are not certified by GitHub. They are provided
+# by a third-party and are governed by separate terms of service, privacy
+# policy, and support documentation.
+
+name: Scorecards supply-chain security
+on:
+  # For Branch-Protection check. Only the default branch is supported. See
+  # https://github.com/ossf/scorecard/blob/main/docs/checks.md#branch-protection
+  branch_protection_rule:
+  # To guarantee Maintained check is occasionally updated. See
+  # https://github.com/ossf/scorecard/blob/main/docs/checks.md#maintained
+  schedule:
+    - cron: '22 4 * * 2'
+  push:
+    branches: [ "master" ]
+
+# Declare default permissions as read only.
+permissions: read-all
+
+jobs:
+  analysis:
+    name: Scorecards analysis
+    runs-on: ubuntu-latest
+    permissions:
+      # Needed to upload the results to code-scanning dashboard.
+      security-events: write
+      # Needed to publish results and get a badge (see publish_results below).
+      id-token: write
+      # Uncomment the permissions below if installing in a private repository.
+      # contents: read
+      # actions: read
+
+    steps:
+      - name: "Checkout code"
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          persist-credentials: false
+
+      - name: "Run analysis"
+        uses: ossf/scorecard-action@ea651e62978af7915d09fe2e282747c798bf2dab # v2.4.1
+        with:
+          results_file: results.sarif
+          results_format: sarif
+          # (Optional) Read-only PAT token. Uncomment the `repo_token` line below if:
+          # - you want to enable the Branch-Protection check on a *public* repository, or
+          # - you are installing Scorecards on a *private* repository
+          # To create the PAT, follow the steps in https://github.com/ossf/scorecard-action#authentication-with-pat.
+          repo_token: ${{ secrets.SCORECARD_READ_TOKEN }}
+
+          # Public repositories:
+          #   - Publish results to OpenSSF REST API for easy access by consumers
+          #   - Allows the repository to include the Scorecard badge.
+          #   - See https://github.com/ossf/scorecard-action#publishing-results.
+          # For private repositories:
+          #   - `publish_results` will always be set to `false`, regardless
+          #     of the value entered here.
+          publish_results: true
+
+      # Upload the results as artifacts (optional). Commenting out will disable uploads of run results in SARIF
+      # format to the repository Actions tab.
+      - name: "Upload artifact"
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
+        with:
+          name: SARIF file
+          path: results.sarif
+          retention-days: 5
+
+      # Upload the results to GitHub's code scanning dashboard.
+      - name: "Upload to code-scanning"
+        uses: github/codeql-action/upload-sarif@959cbb7472c4d4ad70cdfe6f4976053fe48ab394 # v2.1.27
+        with:
+          sarif_file: results.sarif
diff --git a/.github/workflows/spec_guards.yml b/.github/workflows/spec_guards.yml
new file mode 100644
index 0000000000..4521195a2b
--- /dev/null
+++ b/.github/workflows/spec_guards.yml
@@ -0,0 +1,71 @@
+name: Rubyspec Version Guards Check
+
+on:
+  push:
+    paths:
+      - 'spec/**'
+      - '!spec/*.md'
+  pull_request:
+    paths:
+      - 'spec/**'
+      - '!spec/*.md'
+  merge_group:
+
+concurrency:
+  group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
+  cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
+
+permissions:
+  contents: read
+
+jobs:
+  rubyspec:
+    name: Rubyspec
+
+    runs-on: ubuntu-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-3.1
+          - ruby-3.2
+
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+
+      - uses: ruby/setup-ruby@13e7a03dc3ac6c3798f4570bfead2aed4d96abfb # v1.244.0
+        with:
+          ruby-version: ${{ matrix.ruby }}
+          bundler: none
+
+      - run: gem install webrick
+
+      - run: ruby ../mspec/bin/mspec
+        working-directory: spec/ruby
+        env:
+          CHECK_LEAKS: true
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
+        with:
+          payload: |
+            {
+              "ci": "GitHub Actions",
+              "env": "${{ github.workflow }} / rubyspec @ ${{ matrix.ruby }}",
+              "url": "https://github.com/${{ 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() }}
diff --git a/.github/workflows/ubuntu.yml b/.github/workflows/ubuntu.yml
new file mode 100644
index 0000000000..4fbca1170e
--- /dev/null
+++ b/.github/workflows/ubuntu.yml
@@ -0,0 +1,146 @@
+name: Ubuntu
+on:
+  push:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  pull_request:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+
+concurrency:
+  group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
+  cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
+
+permissions:
+  contents: read
+
+jobs:
+  make:
+    strategy:
+      matrix:
+        # main variables included in the job name
+        test_task: [check]
+        configure: [cppflags=-DRUBY_DEBUG] # default to use more assertions
+        arch: ['']
+        # specify all jobs with `include` to avoid testing duplicated things
+        include:
+          - test_task: check
+          - test_task: check
+            arch: i686
+            configure: '' # test without -DRUBY_DEBUG as well
+          - test_task: check
+            configure: "--enable-shared --enable-load-relative"
+          - test_task: test-all TESTS=--repeat-count=2
+          - test_task: test-bundler-parallel
+          - test_task: test-bundled-gems
+      fail-fast: false
+    env:
+      GITPULLOPTIONS: --no-tags origin ${{github.ref}}
+      RUBY_DEBUG: ci
+      SETARCH: ${{ matrix.arch && format('setarch {0}', matrix.arch) }}
+    runs-on: ubuntu-22.04
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    steps:
+      - run: mkdir build
+        working-directory:
+      - name: Set ENV
+        run: |
+          echo "GNUMAKEFLAGS=-j$((1 + $(nproc --all)))" >> $GITHUB_ENV
+      - name: Install libraries
+        env:
+          arch: ${{matrix.arch}}
+        run: |
+          set -x
+          arch=${arch:+:${arch/i[3-6]86/i386}}
+          ${arch:+sudo dpkg --add-architecture ${arch#:}}
+          sudo apt-get update -q || :
+          sudo apt-get install --no-install-recommends -q -y \
+          ${arch:+cross}build-essential${arch/:/-} \
+          libssl-dev${arch} libyaml-dev${arch} libreadline6-dev${arch} \
+          zlib1g-dev${arch} libncurses5-dev${arch} libffi-dev${arch} \
+          bison autoconf ruby
+          sudo apt-get install -q -y pkg-config${arch} || :
+      - name: git config
+        run: |
+          git config --global advice.detachedHead 0
+          git config --global init.defaultBranch garbage
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          path: src
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        with:
+          path: src/.downloaded-cache
+          key: downloaded-cache
+      - name: Fixed world writable dirs
+        run: |
+          chmod -v go-w $HOME $HOME/.config
+          sudo chmod -R go-w /usr/share
+          sudo bash -c 'IFS=:; for d in '"$PATH"'; do chmod -v go-w $d; done' || :
+      - run: ./autogen.sh
+        working-directory: src
+      - name: Run configure
+        env:
+          arch: ${{matrix.arch}}
+        run: >-
+          $SETARCH ../src/configure -C --disable-install-doc ${{ matrix.configure }}
+          ${arch:+--target=$arch-$OSTYPE --host=$arch-$OSTYPE}
+      - run: $SETARCH make incs
+      - run: $SETARCH make prepare-gems
+        if: ${{ matrix.test_task == 'test-bundled-gems' }}
+      - run: $SETARCH make
+      - run: $SETARCH make leaked-globals
+        if: ${{ matrix.test_task == 'check' }}
+      - name: Create dummy files in build dir
+        run: |
+          $SETARCH ./miniruby -e '(("a".."z").to_a+("A".."Z").to_a+("0".."9").to_a+%w[foo bar test zzz]).each{|basename|File.write("#{basename}.rb", "raise %(do not load #{basename}.rb)")}'
+        if: ${{ matrix.test_task == 'check' }}
+      - name: make ${{ matrix.test_task }}
+        run: |
+          $SETARCH make -s ${{ matrix.test_task }} ${TESTS:+TESTS=`echo "$TESTS" | sed 's| |$$/ -n!/|g;s|^|-n!/|;s|$|$$/|'`}
+        timeout-minutes: 40
+        env:
+          RUBY_TESTOPTS: "-q --tty=no"
+          TESTS: ${{ matrix.test_task == 'check' && matrix.skipped_tests || '' }}
+          TEST_BUNDLED_GEMS_ALLOW_FAILURES: ""
+          PRECHECK_BUNDLED_GEMS: "no"
+      - name: make skipped tests
+        run: |
+          $SETARCH make -s test-all TESTS=`echo "$TESTS" | sed 's| |$$/ -n/|g;s|^|-n/|;s|$|$$/|'`
+        env:
+          GNUMAKEFLAGS: ""
+          RUBY_TESTOPTS: "-v --tty=no"
+          TESTS: ${{ matrix.skipped_tests }}
+        if: ${{ matrix.test_task == 'check' && matrix.skipped_tests != '' }}
+        continue-on-error: ${{ matrix.continue-on-skipped_tests || false }}
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
+        with:
+          payload: |
+            {
+              "ci": "GitHub Actions",
+              "env": "${{ github.workflow }} / ${{ matrix.test_task }} ${{ matrix.configure }}${{ matrix.arch }}",
+              "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
+              "commit": "${{ github.sha }}",
+              "branch": "${{ github.ref_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/wasm.yml b/.github/workflows/wasm.yml
new file mode 100644
index 0000000000..27920b5821
--- /dev/null
+++ b/.github/workflows/wasm.yml
@@ -0,0 +1,146 @@
+name: WebAssembly
+on:
+  push:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  pull_request:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+
+concurrency:
+  group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
+  cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
+
+permissions:  # added using https://github.com/step-security/secure-workflows
+  contents: read
+
+jobs:
+  make:
+    strategy:
+      matrix:
+        entry:
+#         # wasmtime can't compile non-optimized Asyncified binary due to locals explosion
+#         - { name: O0-debuginfo, optflags: "-O0", debugflags: "-g", wasmoptflags: "-O1" }
+#         - { name: O1,           optflags: "-O1", debugflags: ""  , wasmoptflags: "-O1" }
+          - { name: O2,           optflags: "-O2", debugflags: ""  , wasmoptflags: "-O2" }
+#         - { name: O3,           optflags: "-O3", debugflags: ""  , wasmoptflags: "-O3" }
+#         # -O4 is equivalent to -O3 in clang, but it's different in wasm-opt
+#         - { name: O4,           optflags: "-O3", debugflags: ""  , wasmoptflags: "-O4" }
+#         - { name: Oz,           optflags: "-Oz", debugflags: ""  , wasmoptflags: "-Oz" }
+      fail-fast: false
+    env:
+      RUBY_TESTOPTS: '-q --tty=no'
+      GITPULLOPTIONS: --no-tags origin ${{github.ref}}
+      WASI_SDK_VERSION_MAJOR: 14
+      WASI_SDK_VERSION_MINOR: 0
+      BINARYEN_VERSION: 109
+      WASMTIME_VERSION: v0.33.0
+    runs-on: ubuntu-22.04
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    steps:
+      - run: mkdir build
+        working-directory:
+      - name: git config
+        run: |
+          git config --global advice.detachedHead 0
+          git config --global init.defaultBranch garbage
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          path: src
+      - name: Install libraries
+        run: |
+          set -ex
+          sudo apt-get update -q || :
+          sudo apt-get install --no-install-recommends -q -y ruby bison make autoconf git wget
+
+          wasi_sdk_deb="wasi-sdk_${WASI_SDK_VERSION_MAJOR}.${WASI_SDK_VERSION_MINOR}_amd64.deb"
+          wget "https://github.com/WebAssembly/wasi-sdk/releases/download/wasi-sdk-${WASI_SDK_VERSION_MAJOR}/${wasi_sdk_deb}"
+          sudo dpkg -i "$wasi_sdk_deb"
+          rm -f "$wasi_sdk_deb"
+
+          mkdir build-sdk
+          pushd build-sdk
+
+          wasmtime_url="https://github.com/bytecodealliance/wasmtime/releases/download/${WASMTIME_VERSION}/wasmtime-${WASMTIME_VERSION}-x86_64-linux.tar.xz"
+          wget -O - "$wasmtime_url" | tar xJf -
+          sudo ln -fs "$PWD/wasmtime-${WASMTIME_VERSION}-x86_64-linux/wasmtime" /usr/local/bin/wasmtime
+
+          binaryen_tarball="binaryen-version_${BINARYEN_VERSION}-x86_64-linux.tar.gz"
+          binaryen_url="https://github.com/WebAssembly/binaryen/releases/download/version_${BINARYEN_VERSION}/${binaryen_tarball}"
+          wget -O - "$binaryen_url" | tar xfz -
+          sudo ln -fs "$PWD/binaryen-version_${BINARYEN_VERSION}/bin/wasm-opt" /usr/local/bin/wasm-opt
+        working-directory: src
+      - name: Set ENV
+        run: |
+          echo "MAKEFLAGS=-j$((1 + $(sysctl -n hw.activecpu)))" >> $GITHUB_ENV
+          echo "WASI_SDK_PATH=/opt/wasi-sdk" >> $GITHUB_ENV
+      - run: ./autogen.sh
+        working-directory: src
+
+      - uses: ruby/setup-ruby@13e7a03dc3ac6c3798f4570bfead2aed4d96abfb # v1.244.0
+        with:
+          ruby-version: '3.0'
+          bundler: none
+
+      - name: Download config.guess with wasi version
+        run: |
+          rm tool/config.guess tool/config.sub
+          ruby tool/downloader.rb -d tool -e gnu config.guess config.sub
+        working-directory: src
+
+      - name: Run configure
+        run: |
+          ../src/configure \
+            --host wasm32-unknown-wasi \
+            --with-static-linked-ext \
+            LDFLAGS=" \
+              -Xlinker --stack-first \
+              -Xlinker -z -Xlinker stack-size=16777216 \
+            " \
+            optflags="${{ matrix.entry.optflags }}" \
+            debugflags="${{ matrix.entry.debugflags }}" \
+            wasmoptflags="${{ matrix.entry.wasmoptflags }} ${{ matrix.entry.debugflags }}"
+
+      # miniruby may not be built when cross-compling
+      - run: make mini ruby
+      - name: Run basictest
+        run: wasmtime run ./../build/miniruby --mapdir /::./ -- basictest/test.rb
+        working-directory: src
+      - name: Run bootstraptest (no thread)
+        run: |
+          NO_THREAD_TESTS="$(grep -L Thread -R ./bootstraptest | awk -F/ '{ print $NF }' | uniq | sed -n 's/test_\(.*\).rb/\1/p' | paste -s -d, -)"
+          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
new file mode 100644
index 0000000000..c2bd4881c2
--- /dev/null
+++ b/.github/workflows/windows.yml
@@ -0,0 +1,149 @@
+name: Windows
+on:
+  push:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  pull_request:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+
+concurrency:
+  group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
+  cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
+
+permissions:
+  contents: read
+
+jobs:
+  make:
+    strategy:
+      matrix:
+        include:
+          - vs: 2022
+            vcvers: -vcvars_ver=14.2
+      fail-fast: false
+    runs-on: windows-${{ 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 }}
+    steps:
+      - run: md build
+        working-directory:
+      - uses: msys2/setup-msys2@61f9e5e925871ba6c9e3e8da24ede83ea27fa91f # v2.27.0
+        id: setup-msys2
+        with:
+          update: true
+          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@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        with:
+          path: C:\vcpkg\installed
+          key: ${{ runner.os }}-vcpkg-installed-windows-${{ matrix.vs }}-${{ github.sha }}
+          restore-keys: |
+            ${{ runner.os }}-vcpkg-installed-windows-${{ 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
+        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@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          path: src
+      - 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 Path=D:/a/_temp/msys64/usr/bin;%Path%
+          if not "%VCVARS%" == "" goto :vcset
+            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% ${{ matrix.vcvers || ''}}
+          set TMP=%USERPROFILE%\AppData\Local\Temp
+          set TEMP=%USERPROFILE%\AppData\Local\Temp
+          set /a TEST_JOBS=(15 * %NUMBER_OF_PROCESSORS% / 10) > nul
+          set | C:\msys64\usr\bin\sort > new.env
+          C:\msys64\usr\bin\comm -13 old.env new.env >> %GITHUB_ENV%
+          del *.env
+      - name: compiler version
+        run: cl
+      - name: link libraries
+        run: |
+          for %%I in (C:\vcpkg\installed\x64-windows\bin\*.dll) do (
+            if not %%~nI == readline mklink %%~nxI %%I
+          )
+          for %%I in (libcrypto-1_1-x64 libssl-1_1-x64) do (
+            ren c:\Windows\System32\%%I.dll %%I.dll_
+          )
+      - name: Configure
+        run: >-
+          ../src/win32/configure.bat --disable-install-doc
+          --with-opt-dir=C:/vcpkg/installed/x64-windows
+      - run: nmake incs
+      - run: nmake extract-extlibs
+      - run: nmake
+        env:
+          YACC: bison.exe
+      - run: nmake test
+        timeout-minutes: 5
+      - run: nmake test-spec
+        timeout-minutes: 10
+      - run: nmake test-all
+        env:
+          RUBY_TESTOPTS: -j${{env.TEST_JOBS}} --job-status=normal
+        timeout-minutes: 60
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
+        with:
+          payload: |
+            {
+              "ci": "GitHub Actions",
+              "env": "VS${{ matrix.vs }} / ${{ matrix.test_task || 'check' }}",
+              "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
+              "commit": "${{ github.sha }}",
+              "branch": "${{ github.ref_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
+    shell: cmd
diff --git a/.github/workflows/yjit-ubuntu.yml b/.github/workflows/yjit-ubuntu.yml
new file mode 100644
index 0000000000..0b7b9046e9
--- /dev/null
+++ b/.github/workflows/yjit-ubuntu.yml
@@ -0,0 +1,170 @@
+name: YJIT Ubuntu
+on:
+  push:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  pull_request:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+  merge_group:
+    paths-ignore:
+      - 'doc/**'
+      - '**/man'
+      - '**.md'
+      - '**.rdoc'
+      - '**/.document'
+
+concurrency:
+  group: ${{ github.workflow }} / ${{ startsWith(github.event_name, 'pull') && github.ref_name || github.sha }}
+  cancel-in-progress: ${{ startsWith(github.event_name, 'pull') }}
+
+permissions:
+  contents: read
+
+jobs:
+  cargo:
+    name: Rust cargo test
+    # GitHub Action's image seems to already contain a Rust 1.58.0.
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      # For now we can't run cargo test --offline because it complains about the
+      # capstone dependency, even though the dependency is optional
+      #- run: cargo test --offline
+      - run: RUST_BACKTRACE=1 cargo test
+        working-directory: yjit
+      # Also compile and test with all features enabled
+      - run: RUST_BACKTRACE=1 cargo test --all-features
+        working-directory: yjit
+      # Check that we can build in release mode too
+      - run: cargo build --release
+        working-directory: yjit
+  make:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - test_task: 'yjit-bindgen'
+            hint: 'To fix: use patch in logs'
+            configure: '--with-gcc=clang-14 --enable-yjit=dev'
+            libclang_path: '/usr/lib/llvm-14/lib/libclang.so.1'
+
+          - test_task: "check"
+            # YJIT should be automatically built in release mode on x86-64 Linux with rustc present
+            #configure: "--enable-yjit RUSTC='rustc +1.58.0'"
+            configure: "RUSTC='rustc +1.58.0'"
+            rust_version: "1.58.0"
+
+          - test_task: "check"
+            configure: "--enable-yjit=dev"
+
+          - test_task: "check"
+            configure: "--enable-yjit=dev"
+            yjit_opts: "--yjit-call-threshold=1 --yjit-verify-ctx"
+
+          - test_task: "test-all TESTS=--repeat-count=2"
+            configure: "--enable-yjit=dev"
+
+          - test_task: "test-bundled-gems"
+            configure: "--enable-yjit=dev"
+
+          - test_task: "yjit-bench"
+            configure: "--enable-yjit=dev"
+            yjit_bench_opts: "--yjit-stats"
+    env:
+      GITPULLOPTIONS: --no-tags origin ${{github.ref}}
+      RUN_OPTS: ${{ matrix.yjit_opts }}
+      YJIT_BENCH_OPTS: ${{ matrix.yjit_bench_opts }}
+      RUBY_DEBUG: ci
+      BUNDLE_JOBS: 8 # for yjit-bench
+    runs-on: ubuntu-22.04
+    if: ${{ !contains(github.event.head_commit.message, '[DOC]') && !contains(github.event.pull_request.labels.*.name, 'Documentation') }}
+    steps:
+      - run: mkdir build
+        working-directory:
+      - name: Install libraries
+        run: |
+          set -x
+          sudo apt-get update -q || :
+          sudo apt-get install --no-install-recommends -q -y build-essential libssl-dev libyaml-dev libreadline6-dev zlib1g-dev libncurses5-dev libffi-dev bison autoconf ruby
+      - name: Install Rust
+        if: ${{ matrix.rust_version }}
+        run: rustup install ${{ matrix.rust_version }} --profile minimal
+      - name: git config
+        run: |
+          git config --global advice.detachedHead 0
+          git config --global init.defaultBranch garbage
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          path: src
+      - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        with:
+          path: src/.downloaded-cache
+          key: downloaded-cache
+      - name: Fixed world writable dirs
+        run: |
+          chmod -v go-w $HOME $HOME/.config
+          sudo chmod -R go-w /usr/share
+          sudo bash -c 'IFS=:; for d in '"$PATH"'; do chmod -v go-w $d; done' || :
+      - name: Set ENV
+        run: |
+          echo "GNUMAKEFLAGS=-j$((1 + $(nproc --all)))" >> $GITHUB_ENV
+      - run: ./autogen.sh
+        working-directory: src
+      - name: Run configure
+        run: ../src/configure -C --disable-install-doc --prefix=$(pwd)/install ${{ matrix.configure }}
+      - run: make incs
+      - run: make prepare-gems
+        if: ${{ matrix.test_task == 'test-bundled-gems' }}
+      - run: make -j
+      - run: make leaked-globals
+        if: ${{ matrix.test_task == 'check' }}
+      - name: Create dummy files in build dir
+        run: |
+          ./miniruby -e '(("a".."z").to_a+("A".."Z").to_a+("0".."9").to_a+%w[foo bar test zzz]).each{|basename|File.write("#{basename}.rb", "raise %(do not load #{basename}.rb)")}'
+        if: ${{ matrix.test_task == 'check' }}
+      - name: Enable YJIT through ENV
+        run: echo "RUBY_YJIT_ENABLE=1" >> $GITHUB_ENV
+      # Check that the binary was built with YJIT
+      - name: Check YJIT enabled
+        run: ./miniruby --yjit -v | grep "+YJIT"
+      - name: make ${{ matrix.test_task }}
+        run: make -s -j ${{ matrix.test_task }} RUN_OPTS="$RUN_OPTS" YJIT_BENCH_OPTS="$YJIT_BENCH_OPTS"
+        timeout-minutes: 60
+        env:
+          RUBY_TESTOPTS: "-q --tty=no"
+          TEST_BUNDLED_GEMS_ALLOW_FAILURES: ""
+          PRECHECK_BUNDLED_GEMS: "no"
+          LIBCLANG_PATH: ${{ matrix.libclang_path }}
+        continue-on-error: ${{ matrix.test_task == 'yjit-bench' }}
+      - name: Show ${{ github.event.pull_request.base.ref }} GitHub URL for yjit-bench comparison
+        run: echo "https://github.com/${BASE_REPO}/commit/${BASE_SHA}"
+        env:
+          BASE_REPO: ${{ github.event.pull_request.base.repo.full_name }}
+          BASE_SHA: ${{ github.event.pull_request.base.sha }}
+        if: ${{ matrix.test_task == 'yjit-bench' && startsWith(github.event_name, 'pull') }}
+      - uses: ruby/action-slack@0bd85c72233cdbb6a0fe01d37aaeff1d21b5fce1 # v3.2.1
+        with:
+          payload: |
+            {
+              "ci": "GitHub Actions",
+              "env": "${{ github.workflow }} / ${{ matrix.test_task }} ${{ matrix.configure }}",
+              "url": "https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}",
+              "commit": "${{ github.sha }}",
+              "branch": "${{ github.ref_name }}"
+            }
+        env:
+          SLACK_WEBHOOK_URL: ${{ secrets.SIMPLER_ALERTS_URL }} # ruby-lang slack: ruby/simpler-alerts-bot
+        if: ${{ failure() && github.event_name == 'push' }}
+
+defaults:
+  run:
+    working-directory: build
diff --git a/.gitignore b/.gitignore
index ab21f6c223..99d32a1825 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,38 +4,53 @@
 *.a
 *.bak
 *.bc
+*.bundle
 *.dSYM
 *.dmyh
 *.dylib
 *.elc
 *.i
+*.ii
 *.inc
 *.log
 *.o
+*.o.tmp
 *.obj
+*.old
 *.orig
+*.pch
 *.pdb
+*.rbinc
 *.rej
 *.s
 *.sav
+*.sl
+*.so
+*.so.*
 *.swp
 *.yarb
 *~
-.*-*
 .*.list
 .*.time
 .DS_Store
+.bundle
 .ccmalloc
 .ext
 .pc
 .ppack
 .svn
+.time
+.ruby-version
 Makefile
-Makefile.old
 cygruby*.def
 extconf.h
 y.output
 y.tab.c
+*.gcda
+*.gcno
+*.gcov
+*.vscode
+lcov*.info
 
 # /
 /*-fake.rb
@@ -45,13 +60,13 @@ y.tab.c
 /*.pc
 /*.rc
 /*_prelude.c
+/.downloaded-cache
+/.top-enc.mk
+/build*/
 /COPYING.LIB
-/ChangeLog-*
-/ChangeLog.pre-alpha
-/ChangeLog.pre1_1
+/ChangeLog
 /Doxyfile
 /GNUmakefile
-/GNUmakefile.old
 /README.atheos
 /README.fat-patch
 /README.v6
@@ -59,6 +74,7 @@ y.tab.c
 /archive
 /autom4te*.cache
 /automake
+/benchmark/benchmark-driver
 /beos
 /bmlog-*
 /breakpoints.gdb
@@ -82,6 +98,9 @@ y.tab.c
 /goruby
 /id.[ch]
 /largefile.h
+/lcov-c-out
+/lcov-rb-out
+/lcov-out
 /lex.c
 /libruby*.*
 /miniprelude.c
@@ -97,19 +116,25 @@ y.tab.c
 /ppack
 /prelude.c
 /preview
+/probes.dmyh
 /probes.h
 /rbconfig.rb
 /rename2.h
 /repack
 /revision.h
+/revision.tmp
 /riscos
 /rubicon
 /ruby
 /ruby-runner
 /ruby-runner.h
 /ruby-man.rd.gz
+/rubyspec_temp
+/run.gdb
 /sizes.c
+/static-ruby
 /test.rb
+/test-coverage.dat
 /tmp
 /transdb.h
 /uncommon.mk
@@ -118,7 +143,15 @@ y.tab.c
 /web
 /yasmdata.rb
 
+# /bin/
+
+/bin/*.exe
+/bin/*.dll
+/bin/goruby
+/bin/ruby
+
 # /benchmark/
+/benchmark/bm_require.data
 /benchmark/bmx_*.rb
 /benchmark/fasta.output.*
 /benchmark/wc.input
@@ -126,25 +159,37 @@ y.tab.c
 /enc/*.def
 /enc/*.exp
 /enc/*.lib
+/enc/jis/props.h
 /enc/unicode/data
 
+# /coroutine/
+!/coroutine/**/*.s
+
 # /enc/trans/
 /enc/trans/*.c
 /enc/trans/*.def
 /enc/trans/*.exp
 /enc/trans/*.lib
-/enc/trans/.time
+
+# /exe/
+/exe/goruby
+/exe/ruby
 
 # /ext/
 /ext/extinit.c
+/ext/configure-ext.mk
+/ext/*/exts.mk
+
+# /ext/-test-/cxxanyargs
+/ext/-test-/cxxanyargs/failure*.failed
 
 # /ext/-test-/win32/dln/
+/ext/-test-/win32/dln/dlntest.dll
 /ext/-test-/win32/dln/dlntest.exp
 /ext/-test-/win32/dln/dlntest.lib
 
-# /ext/dl/callback/
-/ext/dl/callback/callback-*.c
-/ext/dl/callback/callback.c
+# /ext/-test-/gems
+/ext/-test-/gems
 
 # /ext/etc/
 /ext/etc/constdefs.h
@@ -154,9 +199,11 @@ y.tab.c
 
 # /ext/rbconfig/
 /ext/rbconfig/sizeof/sizes.c
+/ext/rbconfig/sizeof/limits.c
 
 # /ext/ripper/
 /ext/ripper/eventids1.c
+/ext/ripper/.eventids2-check
 /ext/ripper/eventids2table.c
 /ext/ripper/ripper.*
 /ext/ripper/ids1
@@ -167,15 +214,20 @@ y.tab.c
 /ext/socket/constdefs.h
 /ext/socket/constdefs.c
 
-# /ext/tk/
-/ext/tk/config_list
-
 # /gems
 /gems/*.gem
+/gems/src
+/gems/*-*
 
-# /spec/
-/spec/mspec
-/spec/rubyspec
+# /lib/
+/lib/ruby/[1-9]*.*
+/lib/ruby/vendor_ruby
+
+# /misc/
+/misc/**/__pycache__
+
+# /spec/bundler
+/.rspec_status
 
 # /tool/
 /tool/config.guess
@@ -183,4 +235,16 @@ y.tab.c
 
 # /win32/
 /win32/*.ico
-/win32/.time
+
+# MJIT
+/include/ruby-*/*/rb_mjit_min_header-*.h
+/lib/ruby_vm/mjit/instruction.rb
+/mjit_config.h
+/rb_mjit_header.h
+
+# YJIT
+/yjit-bench
+/yjit_exit_locations.dump
+
+# /wasm/
+/wasm/tests/*.wasm
diff --git a/.indent.pro b/.indent.pro
index 6a207a0554..1d61cbcad1 100644
--- a/.indent.pro
+++ b/.indent.pro
@@ -2,12 +2,15 @@
 -nbbb
 -nbc
 -br
+-brs
 -nbs
 -ncdb
--ce
--cli0.5
+-nce
+-cdw
+-cli2
+-cbi2
 -ndj
--ei
+-ncs
 -nfc1
 -i4
 -l120
@@ -16,6 +19,14 @@
 -psl
 -sc
 -sob
+-sbi4
+-nut
+-par
 
 -TID
 -TVALUE
+-Tst_data_t
+-Tst_index_t
+-Tst_table
+-Trb_data_type_t
+-TFILE
diff --git a/.rdoc_options b/.rdoc_options
new file mode 100644
index 0000000000..760507c7a2
--- /dev/null
+++ b/.rdoc_options
@@ -0,0 +1,4 @@
+---
+page_dir: doc
+main_page: README.md
+title: Documentation for Ruby development version
diff --git a/.rspec_parallel b/.rspec_parallel
new file mode 100644
index 0000000000..aaff198a32
--- /dev/null
+++ b/.rspec_parallel
@@ -0,0 +1,2 @@
+--format progress
+--format ParallelTests::RSpec::RuntimeLogger --out tmp/parallel_runtime_rspec.log
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index 24ce0c9113..0000000000
--- a/.travis.yml
+++ /dev/null
@@ -1,102 +0,0 @@
-# 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.
-
-# This is  a Travis-CI  build configuration file.   The list  of configurations
-# available is located in
-#
-#     http://about.travis-ci.org/docs/user/build-configuration/
-#
-# and as Ruby itself is a project written in C language,
-#
-#     http://about.travis-ci.org/docs/user/languages/c/
-#
-# is also a good place to look at.
-
-# Language specification.
-language: c
-sudo: false
-
-# Compilers.  Several  compilers are  provided in Travis,  so we try  them all.
-# The value set here is visible via $CC environment variable.
-compiler:
-  - gcc
-
-os:
-  - linux
-
-# Dependencies.  Some  header files are missing  in a Travis' worker  VM, so we
-# have  to install  them.  The  "1.9.1" here  is OK.   It is  the  most adopted
-# version string  for Debian/Ubuntu, and  no dependencies have been  changed so
-# far since the 1.9.1 release.
-before_install:
-  - "CONFIG_FLAG="
-  - "JOBS='-j 4'"
-
-# Script is where the test runs.  Note  we just do "make test", not other tests
-# like  test-all, test-rubyspec.   This is  because  they take  too much  time,
-# enough for Travis to shut down the VM as being stalled.
-before_script:
-  - "uname -a"
-  - "uname -r"
-  - "rm -fr .ext autom4te.cache"
-  - "echo $TERM"
-  - "make -f common.mk BASERUBY=ruby MAKEDIRS='mkdir -p' srcdir=. update-config_files"
-  - "autoconf"
-  - "mkdir config_1st config_2nd"
-  - "./configure -C --disable-install-doc --with-gcc=$CC $CONFIG_FLAG"
-  - "cp -pr config.status .ext/include config_1st"
-  - "make reconfig"
-  - "cp -pr config.status .ext/include config_2nd"
-  - "diff -ru config_1st config_2nd"
-  - "make after-update BASERUBY=ruby"
-  - "make -s $JOBS"
-  - "make update-rubyspec"
-script:
-  - "make test TESTOPTS=--color=never"
-  - "make test-all TESTOPTS='-q -j3 --color=never --job-status=normal'"
-  - "make test-rubyspec MSPECOPT=-fm"
-
-# Branch matrix.  Not all branches are Travis-ready so we limit branches here.
-branches:
-  only:
-    - trunk
-    - ruby_2_1
-    - ruby_2_2
-    - ruby_2_3
-    - /^feature\//
-    - /^bug\//
-
-# We want to be notified when something happens.
-notifications:
-  irc:
-    channels:
-      - "irc.freenode.org#ruby-core"
-      - "irc.freenode.org#ruby-ja"
-    on_success: change # [always|never|change] # default: always
-    on_failure: always # [always|never|change] # default: always
-    template:
-      - "%{message} by @%{author}: See %{build_url}"
-
-  # Update ruby-head installed on Travis CI so other projects can test against it.
-  webhooks:
-    urls:
-      - "https://rubies.travis-ci.org/rebuild/ruby-head"
-    on_success: always
-    on_failure: never
-
-  email:
-    - ko1c-failure@atdot.net
-    - shibata.hiroshi@gmail.com
-
-# Local Variables:
-# mode: YAML
-# coding: utf-8-unix
-# indent-tabs-mode: nil
-# tab-width: 4
-# fill-column: 79
-# default-justification: full
-# End:
diff --git a/BSDL b/BSDL
index a009caefea..66d93598aa 100644
--- a/BSDL
+++ b/BSDL
@@ -4,10 +4,10 @@ Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions
 are met:
 1. Redistributions of source code must retain the above copyright
-notice, this list of conditions and the following disclaimer.
+   notice, this list of conditions and the following disclaimer.
 2. Redistributions in binary form must reproduce the above copyright
-notice, this list of conditions and the following disclaimer in the
-documentation and/or other materials provided with the distribution.
+   notice, this list of conditions and the following disclaimer in the
+   documentation and/or other materials provided with the distribution.
 
 THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index ffdf2dd4b8..13df6087ca 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -1,4 +1 @@
-Please see the [official issue tracker] and wiki [HowToContribute].
-
-[official issue tracker]: https://bugs.ruby-lang.org
-[HowToContribute]: https://bugs.ruby-lang.org/projects/ruby/wiki/HowToContribute
+See ["Contributing to Ruby"](https://docs.ruby-lang.org/en/master/contributing_md.html), which includes setup and build instructions.
diff --git a/COPYING b/COPYING
index 426810a7fb..48e5a96de7 100644
--- a/COPYING
+++ b/COPYING
@@ -2,55 +2,55 @@ Ruby is copyrighted free software by Yukihiro Matsumoto <matz@netlab.jp>.
 You can redistribute it and/or modify it under either the terms of the
 2-clause BSDL (see the file BSDL), or the conditions below:
 
-  1. You may make and give away verbatim copies of the source form of the
-     software without restriction, provided that you duplicate all of the
-     original copyright notices and associated disclaimers.
+1. You may make and give away verbatim copies of the source form of the
+   software without restriction, provided that you duplicate all of the
+   original copyright notices and associated disclaimers.
 
-  2. You may modify your copy of the software in any way, provided that
-     you do at least ONE of the following:
+2. You may modify your copy of the software in any way, provided that
+   you do at least ONE of the following:
 
-       a) place your modifications in the Public Domain or otherwise
-          make them Freely Available, such as by posting said
-	  modifications to Usenet or an equivalent medium, or by allowing
-	  the author to include your modifications in the software.
+   a. place your modifications in the Public Domain or otherwise
+      make them Freely Available, such as by posting said
+      modifications to Usenet or an equivalent medium, or by allowing
+      the author to include your modifications in the software.
 
-       b) use the modified software only within your corporation or
-          organization.
+   b. use the modified software only within your corporation or
+      organization.
 
-       c) give non-standard binaries non-standard names, with
-          instructions on where to get the original software distribution.
+   c. give non-standard binaries non-standard names, with
+      instructions on where to get the original software distribution.
 
-       d) make other distribution arrangements with the author.
+   d. make other distribution arrangements with the author.
 
-  3. You may distribute the software in object code or binary form,
-     provided that you do at least ONE of the following:
+3. You may distribute the software in object code or binary form,
+   provided that you do at least ONE of the following:
 
-       a) distribute the binaries and library files of the software,
-	  together with instructions (in the manual page or equivalent)
-	  on where to get the original distribution.
+   a. distribute the binaries and library files of the software,
+      together with instructions (in the manual page or equivalent)
+      on where to get the original distribution.
 
-       b) accompany the distribution with the machine-readable source of
-	  the software.
+   b. accompany the distribution with the machine-readable source of
+      the software.
 
-       c) give non-standard binaries non-standard names, with
-          instructions on where to get the original software distribution.
+   c. give non-standard binaries non-standard names, with
+      instructions on where to get the original software distribution.
 
-       d) make other distribution arrangements with the author.
+   d. make other distribution arrangements with the author.
 
-  4. You may modify and include the part of the software into any other
-     software (possibly commercial).  But some files in the distribution
-     are not written by the author, so that they are not under these terms.
+4. You may modify and include the part of the software into any other
+   software (possibly commercial).  But some files in the distribution
+   are not written by the author, so that they are not under these terms.
 
-     For the list of those files and their copying conditions, see the
-     file LEGAL.
+   For the list of those files and their copying conditions, see the
+   file LEGAL.
 
-  5. The scripts and library files supplied as input to or produced as
-     output from the software do not automatically fall under the
-     copyright of the software, but belong to whomever generated them,
-     and may be sold commercially, and may be aggregated with this
-     software.
+5. The scripts and library files supplied as input to or produced as
+   output from the software do not automatically fall under the
+   copyright of the software, but belong to whomever generated them,
+   and may be sold commercially, and may be aggregated with this
+   software.
 
-  6. THIS SOFTWARE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR
-     IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
-     WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
-     PURPOSE.
+6. THIS SOFTWARE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR
+   IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+   WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+   PURPOSE.
diff --git a/COPYING.ja b/COPYING.ja
index e50d01c8d1..230376bc60 100644
--- a/COPYING.ja
+++ b/COPYING.ja
@@ -2,50 +2,50 @@
 ���以下�示��件�本プログラムを��布����
 2-clause BSDL�����BSDLファイルを�照��下��．
 
-  1. 複製�制���自由��．
+1. 複製�制���自由��．
 
-  2. 以下��件���れ�を満��時�本プログラム�ソースを
-     自由�変更����．
+2. 以下��件���れ�を満��時�本プログラム�ソースを
+   自由�変更����．
 
-     (a) �ットニューズ��スト��り，作者�変更を�付�る
-         ���方法�，変更を公開�る．
+   a.  �ットニューズ��スト��り，作者�変更を�付�る
+       ���方法�，変更を公開�る．
 
-     (b) 変更��本プログラムを自分�所属�る組織内部���
-         使�．
+   b.  変更��本プログラムを自分�所属�る組織内部���
+       使�．
 
-     (c) 変更点を明示����，ソフトウェア���を変更�る．
-         ��ソフトウェアを�布�る時��変更��本プログラ
-         ムも�時��布�る．���変更��本プログラム�ソー
-         ス�入手法を明示�る．
+   c.  変更点を明示����，ソフトウェア���を変更�る．
+       ��ソフトウェアを�布�る時��変更��本プログラ
+       ムも�時��布�る．���変更��本プログラム�ソー
+       ス�入手法を明示�る．
 
-     (d) ��他�変更�件を作者����る．
+   d.  ��他�変更�件を作者����る．
 
-  3. 以下��件���れ�を満��時�本プログラムをコンパイ
-     ル��オブジェクトコードや実行形��も�布����．
+3. 以下��件���れ�を満��時�本プログラムをコンパイ
+   ル��オブジェクトコードや実行形��も�布����．
 
-     (a) �イナリを�����人�ソースを入手��るよ��，
-         ソース�入手法を明示�る．
+   a.  �イナリを�����人�ソースを入手��るよ��，
+       ソース�入手法を明示�る．
 
-     (b) 機械�読�ソースコードを添付�る．
+   b.  機械�読�ソースコードを添付�る．
 
-     (c) 変更を行���イナリ���を変更����，オリジナ
-         ル�ソースコード�入手法を明示�る．
+   c.  変更を行���イナリ���を変更����，オリジナ
+       ル�ソースコード�入手法を明示�る．
 
-     (d) ��他��布�件を作者����る．
+   d.  ��他��布�件を作者����る．
 
-  4. 他�プログラム��引用����る目的��れ自由��．�
-     ��，本プログラム���れる他�作者�よるコード�，�
-     れ�れ�作者����よる制��加�られる場���り��．
+4. 他�プログラム��引用����る目的��れ自由��．�
+   ��，本プログラム���れる他�作者�よるコード�，�
+   れ�れ�作者����よる制��加�られる場���り��．
 
-     �れらファイル�一覧��れ�れ��布�件���付���
-     LEGALファイルを�照������．
+   �れらファイル�一覧��れ�れ��布�件���付���
+   LEGALファイルを�照������．
 
-  5. 本プログラム��入力��るスクリプト�よ�，本プログラ
-     ム�ら�出力�権利�本プログラム�作者����，�れ�
-     れ�入出力を生���人�属���．��，本プログラム�
-     組�込�れる���拡張ライブラリ����も�様��．
+5. 本プログラム��入力��るスクリプト�よ�，本プログラ
+   ム�ら�出力�権利�本プログラム�作者����，�れ�
+   れ�入出力を生���人�属���．��，本プログラム�
+   組�込�れる���拡張ライブラリ����も�様��．
 
-  6. 本プログラム�無�証��．作者�本プログラムをサ�ート
-     �る�志��り���，プログラム自身��グ�る��本プ
-     ログラム�実行���ら発生�る���る�害�対��も責
-     任を����ん．
+6. 本プログラム�無�証��．作者�本プログラムをサ�ート
+   �る�志��り���，プログラム自身��グ�る��本プ
+   ログラム�実行���ら発生�る���る�害�対��も責
+   任を����ん．
diff --git a/ChangeLog b/ChangeLog
deleted file mode 100644
index 8ddd4ad666..0000000000
--- a/ChangeLog
+++ /dev/null
@@ -1,7140 +0,0 @@
-Thu Jul 14 17:26:00 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* Makefile.in (enc/unicode/name2ctype.h): remove stale recipe,
-	  which did not support Unicode age properties.
-
-	* common.mk (enc/unicode/name2ctype.h): update by --header option
-	  of tool/enc-unicode.rb.  enc/unicode/name2ctype.kwd file has not
-	  been used.
-
-	* common.mk (enc/unicode/name2ctype.kwd): rule to create from
-	  Unicode data files, used only when the target does not exist.
-
-Thu Jul 14 13:10:54 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/json/lib/json/ext: remove stale directory.  bundled
-	  extension libraries are placed under the directory for each
-	  architectures, but not mixed with plain text script libraries.
-
-Thu Jul 14 12:48:47 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* ext/json/**/*.rb: merge original files from upstream repository.
-	  It only fixes styles of frozen string literal.
-
-Wed Jul 13 22:23:03 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* test/json/json_common_interface_test.rb: use assert_raise instead of
-	  assert_raises.
-
-Wed Jul 13 22:14:23 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* test/lib/test/unit.rb: added test files with `_test` suffix for json
-	  upstream.
-	* test/json: merge original test files from json upstream.
-
-Wed Jul 13 18:09:42 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_9.c, test/ruby/enc/test_case_comprehensive.rb:
-	  Implement non-ASCII case conversion for ISO-8859-9, by Kazuki Iijima.
-
-	* enc/iso_8859_9.c: Exclude dotless i/I with dot from case-insensitive
-	  matching because they are not a case pair.
-
-	* test/ruby/enc/test_iso_8859.rb: Make test coverage for ISO-8859-9
-	  a bit more complete.
-
-Wed Jul 13 17:21:24 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/windows_1252.c, test/ruby/enc/test_case_comprehensive.rb:
-	  Implement non-ASCII case conversion for Windows-1252, by Serina Tai.
-
-	* test/ruby/enc/test_case_comprehensive.rb: Fix order of encodings.
-
-Wed Jul 13 16:19:14 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_7.c, test/ruby/enc/test_case_comprehensive.rb:
-	  Implement non-ASCII case conversion for ISO-8859-7, by Kosuke Kurihara.
-
-	* test/ruby/enc/test_case_comprehensive.rb: Fix order of encodings.
-
-Wed Jul 13 16:08:08 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c (gc_mark_roots): should mark the VM object itself to mark
-	  singleton class of the VM object.
-	  Before this patch, we only set mark bit for the VM object and
-	  invoke mark function separately.
-	  [Bug #12583]
-
-	* test/ruby/test_gc.rb: add a test.
-
-Wed Jul 13 15:59:59 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* math.c (_USE_MATH_DEFINES): it must be set before including internal.h
-	  because internal.h includes ruby.h, ruby.h includes win32.h, and
-	  win32.h includes system's math.h.
-	  this change is to get rid of a compiler warning (redefinition of
-	  a macro) introduced at r55641.
-
-Wed Jul 13 15:19:03 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_1.c, enc/iso_8859_4.c: Avoid setting modification flag if
-	  there is no modification.
-
-Wed Jul 13 14:40:04 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_5.c, test/ruby/enc/test_case_comprehensive.rb:
-	  Implement non-ASCII case conversion for ISO-8859-5, by Masaru Onodera.
-
-	* test/ruby/enc/test_case_comprehensive.rb: Fix order of encodings.
-
-Wed Jul 13 14:28:33 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* math.c (rb_math_sqrt): r55646 must use f_signbit.
-
-Wed Jul 13 14:22:50 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* iseq.c (Init_ISeq): undef ISeq.translate and ISeq.load_iseq
-	  to prevent calling super classes' methods.
-
-	  Without this patch, you can write workaround like:
-
-	    class << RubyVM::InstructionSequence
-	      def translate; end
-	      undef translate
-	    end
-
-	* test/ruby/test_iseq.rb: add a test.
-
-Wed Jul 13 14:16:03 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* vm_method.c (method_entry_get_without_cache): check
-	  undefined method even if ruby_running is FALSE.
-
-	  We haven't call "undef"ed methods before ruby_running.
-	  So that this issue does not make troubles.
-
-Wed Jul 13 14:15:22 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/windows_1254.c: Adjust variable/macro names.
-
-Wed Jul 13 13:19:12 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_9.c, enc/windows_1254.c: Split Windows-1254 from
-	  ISO-8859-9 to be able to implement different case conversions.
-
-Wed Jul 13 13:08:30 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_7.c, enc/windows_1253.c: Split Windows-1253 from
-	  ISO-8859-7 to be able to implement different case conversions.
-
-Wed Jul 13 10:50:12 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_13.c, test/ruby/enc/test_case_comprehensive.rb:
-	  Implement non-ASCII case conversion for ISO-8859-13, by Kanon Shindo.
-
-Wed Jul 13 10:31:39 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_13.c, enc/windows_1257.c: Split Windows-1257 from
-	  ISO-8859-13 to be able to implement different case conversions.
-
-Wed Jul 13 09:02:30 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_3.c, test/ruby/enc/test_case_comprehensive.rb:
-	  Implement non-ASCII case conversion for ISO-8859-3, by Takuya Miyamoto.
-
-	* test/ruby/enc/test_case_comprehensive.rb: Extend special treatment
-	  for Turkic.
-
-	* enc/iso_8859_3.c: Exclude dotless i/I with dot from case-insensitive
-	  matching because they are not a case pair.
-
-Wed Jul 13 08:40:21 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_iso_8859.rb: Exclude dotless i/I with dot from
-	  case-insensitive matching because they are not a case pair.
-
-Tue Jul 12 23:13:43 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* math.c (rb_math_sqrt): [EXPERIMENTAL] move Complex sqrt support
-	  from mathn.rb.
-
-Tue Jul 12 01:25:09 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* configure.in, lib/mkmf.rb, win32/Makefile.sub (CSRCFLAG): make the
-	  compiler option replacable in Makefile.
-
-	* win32/Makefile.sub (OUTFLAG, COUTFLAG): ditto.
-
-	* win32/Makeile.sub, win32/setup.mak (CC): should not append `-nologo`
-	  option forcely.
-
-Mon Jul 11 18:05:40 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_1.c: Moved test for lowercase characters without
-	  uppercase equivalent.
-
-Mon Jul 11 17:49:25 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_4.c, enc/iso_8859_10.c, enc/iso_8859_14.c,
-	  enc/iso_8859_15.c, enc/iso_8859_16.c: Replace case-by-case code with
-	  lookup in ENC_ISO_8859_xx_TO_LOWER_CASE table.
-
-Mon Jul 11 16:00:56 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/stringio/stringio.c (strio_each, strio_readlines): convert
-	  arguments just once before reading, instead of conversions for
-	  each lines, as r55603.
-
-Sun Jul 10 19:53:41 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_10.c, test/ruby/enc/test_case_comprehensive.rb:
-	  Implement non-ASCII case conversion for ISO-8859-10, by Toya Hosokawa.
-
-Sun Jul 10 19:33:47 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_comprehensive.rb: Changed testing logic to
-	  catch unintended modifications of characters that do not have a case
-	  equivalent in the respective encoding.
-	* enc/iso_8859_1.c, enc/iso_8859_15.c: Fixed unintended modifications of
-	  micro sign and y with diaeresis.
-
-Sun Jul 10 17:05:36 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_4.c, test/ruby/enc/test_case_comprehensive.rb:
-	  Implement non-ASCII case conversion for ISO-8859-4, by Kotaro Yoshida.
-
-Sun Jul 10 16:17:47 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_comprehensive.rb: Fixed a comment
-	  (message belongs to last commit). [ci skip]
-
-Sun Jul 10 14:27:25 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* util.c (ruby_dtoa): [EXPERIMENTAL] adjust the case that the
-	  Float value is close to the exact but unrepresentable middle
-	  value of two values in the given precision, as r55604.
-
-Sun Jul 10 08:57:20 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* thread.c: Fixed implicit conversion error with Apple clang-800.0.31
-
-Sat Jul  9 12:43:09 2016  Shugo Maeda  <shugo@ruby-lang.org>
-
-	* lib/getoptlong.rb: use false instead of FALSE.
-
-Fri Jul  8 21:49:28 2016  Naohisa Goto  <ngotogenome@gmail.com>
-
-	* thread.c (rb_wait_for_single_fd): Clean up fds.revents every time
-	  before calling ppoll(2). [Bug #12575] [ruby-dev:49725]
-
-Fri Jul  8 14:16:48 2016  Shugo Maeda  <shugo@ruby-lang.org>
-
-	* vm_args.c (vm_caller_setup_arg_block): call rb_sym_to_proc()
-	  directly to reduce method dispatch overhead.
-
-Fri Jul  8 08:43:31 2016  Shugo Maeda  <shugo@ruby-lang.org>
-
-	* io.c (rb_io_s_read): add description of pipes to the documentation
-	  of IO.read.
-
-Fri Jul  8 03:54:22 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* vm_args.c (setup_parameters_complex): don't raise ArgumentError
-	  if an array is given for instance_exec with optional argument.
-	  [ruby-core:76300] [Bug #12568]
-	  https://github.com/rails/rails/pull/25699
-
-Fri Jul  8 00:47:36 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* vm_eval.c (yield_under): change prototype to get argc/argv.
-
-	* vm_eval.c (specific_eval): change for above.
-
-	* vm_eval.c (rb_obj_instance_exec): avoid object allocation.
-
-	* vm_eval.c (rb_mod_module_exec): ditto.
-
-Thu Jul  7 20:08:37 2016  Shugo Maeda  <shugo@ruby-lang.org>
-
-	* vm_args.c (vm_caller_setup_arg_block): disable symbol block
-	  argument optimization when tail call optimization is enabled,
-	  in order to avoid SEGV.  [ruby-core:76288] [Bug #12565]
-
-Thu Jul  7 16:37:53 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* numeric.c (flo_round): [EXPERIMENTAL] adjust the case that the
-	  receiver is close to the exact but unrepresentable middle value
-	  of two values in the given precision.
-	  http://d.hatena.ne.jp/hnw/20160702
-
-Thu Jul  7 16:31:07 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* io.c (rb_io_s_foreach, rb_io_s_readlines): convert arguments
-	  just once before reading, instead of conversions for each lines.
-
-Wed Jul  6 19:54:17 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_14.c, test/ruby/enc/test_case_comprehensive.rb:
-	  Implement non-ASCII case conversion for ISO-8859-14, by Yutaro Tada.
-
-Wed Jul  6 19:24:48 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_1.c, enc/iso_8859_15.c, enc/iso_8859_16.c:
-	  Align indenting to onigmo convention.
-
-Wed Jul  6 18:59:13 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_15.c, test/ruby/enc/test_case_comprehensive.rb:
-	  Implement non-ASCII case conversion for ISO-8859-15, by Maho Harada.
-
-Wed Jul  6 18:34:21 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_16.c, test/ruby/enc/test_case_comprehensive.rb:
-	  Implement non-ASCII case conversion for ISO-8859-16, by Satoshi Kayama.
-
-Wed Jul  6 14:44:56 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/mkmf.rb (create_makefile): store $headers in LOCAL_HDRS for
-	  depend files.
-
-	* ext/digest/digest_conf.rb (digest_conf): add implementation
-	  specific headers to $header.
-
-	* ext/digest/{md5,rmd160,sha1,sha2}/depend: add LOCAL_HDRS to the
-	  dependencies.
-
-Wed Jul  6 08:59:35 2016  Shugo Maeda  <shugo@ruby-lang.org>
-
-	* lib/net/http/generic_rquest.rb (write_header): A Request-Line must
-	  not contain CR or LF.
-
-Wed Jul  6 07:11:27 2016  Shugo Maeda  <shugo@ruby-lang.org>
-
-	* lib/net/ftp.rb (putline): raise an ArgumentError when
-	  CR or LF is included in a line.
-
-Tue Jul  5 20:49:30 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* ext/json/*, test/json/*: Update json-2.0.1.
-	  Changes of 2.0.0: https://github.com/flori/json/blob/f679ebd0c69a94e3e70a897ac9a229f5779c2ee1/CHANGES.md#2015-09-11-200
-	  Changes of 2.0.1: https://github.com/flori/json/blob/f679ebd0c69a94e3e70a897ac9a229f5779c2ee1/CHANGES.md#2016-07-01-201
-	  [Feature #12542][ruby-dev:49706][fix GH-1395]
-
-Tue Jul  5 19:39:49 2016  Naohisa Goto  <ngotogenome@gmail.com>
-
-	* string.c (rb_str_change_terminator_length): New function to change
-	  termlen and resize heap for the terminator. This is split from
-	  rb_str_fill_terminator (str_fill_term) because filling terminator
-	  and changing terminator length are different things. [Bug #12536]
-
-	* internal.h: declaration for rb_str_change_terminator_length.
-
-	* string.c (str_fill_term): Simplify only to zero-fill the terminator.
-	  For non-shared strings, it assumes that (capa + termlen) bytes of
-	  heap is allocated. This partially reverts r55557.
-
-	* encoding.c (rb_enc_associate_index): rb_str_change_terminator_length
-	  is used, and it should be called whenever the termlen is changed.
-
-	* string.c (str_capacity): New static function to return capacity
-	  of a string with the given termlen, because the termlen may
-	  sometimes be different from TERM_LEN(str) especially during
-	  changing termlen or filling terminator with specific termlen.
-
-	* string.c (rb_str_capacity): Use str_capacity.
-
-Tue Jul  5 11:07:14 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* pack.c (pack_pack): use union instead of bare variable to ease
-	  optimizations and avoid assigning x87 floating point number.
-	  [ruby-core:74496] [Bug #12209]
-
-	* pack.c (pack_unpack): ditto.
-
-Mon Jul  4 13:56:34 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* process.c: define sig_t if not exist.
-	  at least Solaris 10 and 11 doesn't have sig_t.
-
-Mon Jul  4 13:08:48 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* random.c (random_ulong_limited): avoid left shift count >= width of
-	  type on 32bit environment.
-
-Sun Jul  3 18:51:42 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_comprehensive.rb, test_regex_casefold.rb,
-	  test/test_unicode_normalize.rb: Replace UNICODE_VERSION from
-	  UnicodeNormalize with RbConfig::CONFIG['UNICODE_VERSION'] from
-	  feature 12460.
-
-Sun Jul  3 06:04:09 2016  Eric Wong  <e@80x24.org>
-
-	* process.c (disable_child_handler_fork_child): simplify
-	  [ruby-core:75781] [Misc #12439]
-
-Sun Jul  3 05:25:46 2016  Eric Wong  <e@80x24.org>
-
-	* tool/asm_parse.rb: add description
-	* tool/change_maker.rb: ditto
-	* tool/downloader.rb: ditto
-	* tool/eval.rb: ditto
-	* tool/expand-config.rb: ditto
-	* tool/extlibs.rb: ditto
-	* tool/fake.rb: ditto
-	* tool/file2lastrev.rb: ditto
-	* tool/gem-unpack.rb: ditto
-	* tool/gen_dummy_probes.rb: ditto
-	* tool/gen_ruby_tapset.rb: ditto
-	* tool/generic_erb.rb: ditto
-	* tool/id2token.rb: ditto
-	* tool/ifchange: ditto
-	* tool/insns2vm.rb: ditto
-	* tool/instruction.rb: ditto
-	* tool/jisx0208.rb: ditto
-	* tool/merger.rb: ditto
-	* tool/mkrunnable.rb: ditto
-	* tool/node_name.rb: ditto
-	* tool/parse.rb: ditto
-	* tool/rbinstall.rb: ditto
-	* tool/rbuninstall.rb: ditto
-	* tool/rmdirs: ditto
-	* tool/runruby.rb: ditto
-	* tool/strip-rdoc.rb: ditto
-	* tool/vcs.rb: ditto
-	* tool/vtlh.rb: ditto
-	* tool/ytab.sed: ditto
-	* tool/enc-unicode.rb: fix typo
-	* tool/mk_call_iseq_optimized.rb: ditto
-	* tool/update-deps: ditto
-	  [ruby-core:76215] [Bug #12539]
-	  by Noah Gibbs <the.codefolio.guy@gmail.com>
-
-Sat Jul  2 18:04:24 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* lib/uri/mailto.rb (initialize): RFC3986_Parser#split sets opaque
-	  only if the URI has path-rootless, not path-empty.
-	  [ruby-core:76055] [Bug #12498]
-	  patched by Chris Heisterkamp <cheister@squareup.com>
-
-Sat Jul  2 04:26:14 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* regcomp.c (noname_disable_map): don't optimize out group 0
-	  Ruby's Regexp doesn't allow normal numbered groups if the regexp
-	  has named groups. On such case it optimizes out related NT_ENCLOSE.
-	  But even on the case it can use \g<0>.
-	  This fix not to remove NT_ENCLOSE whose regnum is 0.
-	  [ruby-core:75828] [Bug #12454]
-
-Sat Jul  2 03:09:27 2016  Naohisa Goto  <ngotogenome@gmail.com>
-
-	* string.c: Partially reverts r55547 and r55555.
-	  ChangeLog about the reverted changes are also deleted in this file.
-	  [Bug #12536] [ruby-dev:49699] [ruby-dev:49702]
-
-Sat Jul  2 02:22:22 2016  Naohisa Goto  <ngotogenome@gmail.com>
-
-	* string.c (str_fill_term): When termlen increases, re-allocation
-	  of memory for termlen should always be needed.
-	  In this fix, if possible, decrease capa instead of realloc.
-	  [Bug #12536] [ruby-dev:49699]
-
-Fri Jul  1 20:20:20 2016  Naohisa Goto  <ngotogenome@gmail.com>
-
-	* string.c: Specify termlen as far as possible.
-	  Additional fix for [Bug #12536] [ruby-dev:49699].
-
-	* string.c (str_new_static): Specify termlen from the given encoding
-	  when creating a new String object is needed.
-
-	* string.c (rb_tainted_str_new_with_enc): New function to create a
-	  tainted String object with the given encoding. This means that
-	  the termlen is correctly specified. Currently static function.
-	  The function name might be renamed to rb_tainted_enc_str_new
-	  or rb_enc_tainted_str_new.
-
-	* string.c (rb_external_str_new_with_enc): Use encoding by using the
-	  above rb_tainted_str_new_with_enc().
-
-Fri Jul  1 19:38:57 2016  Naohisa Goto  <ngotogenome@gmail.com>
-
-	* test/fiddle/test_pointer.rb (test_to_str, test_to_s, test_aref_aset):
-	  Attempt to use independent strings for destructive tests that
-	  directly modify values on memory by using Fiddle::Pointer.
-	  [Bug #12537] [ruby-dev:49700]
-
-Fri Jul  1 18:20:00 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* .gdbinit (rb_ps_thread): show the detail of cfunc in ruby level
-	  backtrace.
-
-Fri Jul  1 13:26:39 2016  Naohisa Goto  <ngotogenome@gmail.com>
-
-	* string.c (rb_str_subseq, str_substr): When RSTRING_EMBED_LEN_MAX
-	  is used, TERM_LEN(str) should be considered with it because
-	  embedded strings are also processed by TERM_FILL.
-	  Additional fix for [Bug #12536] [ruby-dev:49699].
-
-Fri Jul  1 12:11:01 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* .gdbinit (rb_count_objects): added gdb version of count_objects().
-
-Fri Jul  1 04:32:52 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* .gdbinit (rb_ps_thread): show ruby level backtrace.
-	  Usually you can call `rb_ps` to show ruby level backtraces
-	  for all living threads.
-	  Note that it can call with core file like `gcore <pid>`
-	  and `gdb ruby core.<pid>`.
-
-Thu Jun 30 19:15:13 2016  Naohisa Goto  <ngotogenome@gmail.com>
-
-	* string.c: Fix memory corruptions when using UTF-16/32 strings.
-	  [Bug #12536] [ruby-dev:49699]
-
-	* string.c (rb_str_new_with_class): Use TERM_LEN of the "obj".
-
-	* string.c (rb_str_plus, rb_str_justify): Use str_new0 which is aware
-	  of termlen.
-
-	* string.c (str_shared_replace): Copy +termlen bytes instead of +1.
-
-	* string.c (rb_str_times): termlen should not be included in capa.
-
-	* string.c (RESIZE_CAPA_TERM): When using RSTRING_EMBED_LEN_MAX,
-	  termlen should be counted with it because embedded strings are
-	  also processed by TERM_FILL.
-
-	* string.c (rb_str_capacity, str_shared_replace, str_buf_cat): ditto.
-
-	* string.c (rb_str_drop_bytes, rb_str_setbyte, str_byte_substr): ditto.
-
-Wed Jun 29 22:24:37 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* ext/psych/lib/psych_jars.rb: removed needless file required to JRuby.
-
-Wed Jun 29 22:21:38 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_ocsp.c: The "reuse" behavior of d2i_ functions does
-	  not work well with OpenSSL 1.0.0t. So avoid it.
-
-Wed Jun 29 15:18:28 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* insns.def (opt_succ): optimize like r55515. (but this argument is
-	  constant)
-
-Wed Jun 29 12:41:58 2016  Shugo Maeda  <shugo@ruby-lang.org>
-
-	* test/ruby/test_refinement.rb: skip
-	  test_prepend_after_refine_wb_miss on ARM or MIPS.
-	  [ruby-core:76031] [Bug #12491]
-
-Wed Jun 29 08:45:53 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* proc.c (passed_block): convert passed block symbol to proc.
-	  based on the patch by Daisuke Sato in [ruby-dev:49695].
-	  [Bug #12531]
-
-Wed Jun 29 03:34:41 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* bignum.c (rb_big2ulong): the old logic seems to try to avoid
-	  calculating `-(long)(num-1)-1` if `num` is not LONG_MIN. (Note that
-	  `-LONG_MIN` may be larger than LONG_MAX) But C compilers can
-	  optimize it into single NEG instruction.
-	  Therefore those two conditions can be single if-body.
-
-	* bignum.c (rb_big2long): ditto.
-
-	* bignum.c (rb_big2ull): ditto.
-
-	* bignum.c (rb_big2ll): ditto.
-
-Tue Jun 28 22:55:00 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/pstore.rb (PStore::CHECKSUM_ALGO): extract the algorithm for
-	  checksum, instead of qualified names for each times.
-
-Tue Jun 28 22:29:36 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* bootstraptest/runner.rb: do not use safe navigation operator.
-	  this runner may run on older ruby.  partially revert r53110
-	  (GH-1142 patched by @mlarraz).
-
-Tue Jun 28 22:09:09 2017  Akio Tajima <artonx@yahoo.co.jp>
-
-	* lib/fileutils.rb: rescue Errno:EACCES for chown.
-	  [Bug #12520]
-
-Tue Jun 28 18:38:09 2016  Naohisa Goto  <ngotogenome@gmail.com>
-
-	* ext/digest/md5/md5ossl.h: Remove excess semicolons.
-	  Suppress warning on Solaris with Oracle Solaris Studio 12.
-	  [ruby-dev:49692] [Bug #12524]
-
-	* ext/digest/md5/md5cc.h: ditto.
-	* ext/digest/sha1/sha1cc.h: ditto.
-	* ext/digest/sha1/sha1ossl.h: ditto.
-	* ext/digest/sha2/sha2cc.h: ditto.
-	* ext/digest/sha2/sha2ossl.h: ditto.
-	* ext/openssl/ossl_pkey_rsa.c: ditto.
-
-Tue Jun 28 15:56:48 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* test/ruby/enc/test_case_comprehensive.rb: noting to test if
-	  Unicode data files are available.
-	  [ruby-core:76160] [Bug #12433]
-
-	* test/test_unicode_normalize.rb: ditto.
-
-Tue Jun 28 15:20:18 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/net/http.rb (Net::HTTP#proxy_uri): cache the case no proxy
-	  is used.
-
-Tue Jun 28 09:56:29 2016  Stefan Schussler  <mail@stefanschuessler.de>
-
-	* object.c (rb_mod_eqq): [DOC] Fix typo in RDoc.  [Fix GH-1393]
-
-Tue Jun 28 02:41:32 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* insns.def (opt_plus): use `- 1` instead of `& (~1)` to allow
-	  compilers to use x86 LEA instruction (3 operand).
-	  Even if 3 operand LEA's latency is 3 cycle after SandyBridge,
-	  it reduces code size and can be faster because of super scalar.
-
-	* insns.def (opt_plus): calculate and use rb_int2big.
-	  On positive Fixnum overflow, `recv - 1 + obj` doesn't carry
-	  because recv's msb and obj's msb are 0, and resulted msb is 1.
-	  Therefore simply rshift and cast as signed long works fine.
-	  On negative Fixnum overflow, it will carry because both arguments'
-	  msb are 1, and resulted msb is also 1.
-	  In this case it needs to restore carried sign bit after rshift.
-
-Mon Jun 27 16:58:32 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/fileutils.rb (FileUtils#install): accecpt symbolic mode, as
-	  well as chmod.
-
-	* lib/fileutils.rb (FileUtils#install): add owner and group
-	  options.
-
-Mon Jun 27 08:56:55 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* compile.c (ADD_TRACE): ignore trace instruction on non-positive
-	  line.
-
-	* parse.y (coverage): get rid of ArgumentError when the starting
-	  line number is not positive.  [ruby-core:76141] [Bug #12517]
-
-Sun Jun 26 10:20:25 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/win32/lib/Win32API.rb (Win32API#initialize): Cygwin
-	  2.5.2-1 (perhaps) seems to no longer append ".dll" suffix
-	  implicitly.
-
-	* ext/win32/lib/win32/resolv.rb (Win32::Resolv): ditto.  Fix the
-	  error reported by yamataka AT u08.itscom.net in
-	  [ruby-list:50339], and pointed out and patched by cerberus AT
-	  m3.kcn.ne.jp in [ruby-list:50341].
-
-Sat Jun 25 10:07:52 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* test/openssl/test_ocsp.rb: Ignore errors caused by bugs that exist in
-	  LibreSSL >= 2.3.1.
-
-Sat Jun 25 02:33:33 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* vm_method.c (vm_respond_to): try method_missing if respond_to?
-	  is undefined, as if it is the default definition.
-	  [ruby-core:75377] [Bug #12353]
-
-Fri Jun 24 17:04:21 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* ext/psych/*, test/psych/*: Update psych 2.1.0
-	  This version fixed [Bug #11988][ruby-core:72850]
-
-Fri Jun 24 13:12:41 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/rubygems.rb, lib/rubygems/*, test/rubygems/*:
-	  Update rubygems 2.6.5 and 2.6.6.
-	  Release note of 2.6.5: https://github.com/rubygems/rubygems/commit/656f5d94dc888d78d0d00f3598a4fa37391aac80
-	  Release note of 2.6.6: https://github.com/rubygems/rubygems/commit/ccb9c3300c063f5b5656669972d24a10ef8afbf5
-
-Fri Jun 24 09:17:15 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* common.mk (lib/unicode_normalize/tables.rb): should not depend
-	  on Unicode data files unless ALWAYS_UPDATE_UNICODE=yes, to get
-	  rid of downloading Unicode data unnecessary.  [ruby-dev:49681]
-
-	* common.mk (enc/unicode/casefold.h): update Unicode files in a
-	  sub-make, not to let the header depend on the files always.
-
-	* enc/unicode/case-folding.rb: if gperf is not usable, assume the
-	  existing file is OK.
-
-Tue Jun 21 19:44:54 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_regex_casefold.rb: Add Windows-1251, KOI8-R, and
-	  KOI8-U to encodings; definitely removed EUC-JP.
-
-Tue Jun 21 19:32:23 2016  Mark St.Godard  <markstgodard@gmail.com>
-
-	* lib/webrick/httprequest.rb (setup_forwarded_info): Use the first
-	  value in X-Forwarded-Proto, if header contains multiple comma
-	  separated values.  Some middlewares may add these values to the
-	  list, not replacing.  [Fix GH-1386]
-
-Tue Jun 21 17:17:42 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/test_io.rb: Skip test_readpartial_with_not_empty_buffer,
-	  test_read_buffer_error, test_read_unlocktmp_ensure,
-	  test_readpartial_unlocktmp_ensure, and
-	  test_sysread_unlocktmp_ensure on cygwin,
-	  because these tests repeatedly hang. This makes test_io.rb
-	  complete in finite time on cygwin.
-
-	* ChangeLog: Fix test_in.rb -> test_io.rb (two instances).
-
-Tue Jun 21 16:38:14 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* string.c (rb_str_casemap): do not put code with side effects
-	  inside RSTRING_PTR() macro which evaluates the argument multiple
-	  times.
-
-Tue Jun 21 16:13:45 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* string.c (rb_str_casemap): fix memory leak.
-
-Tue Jun 21 16:12:21 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* string.c (rb_str_casemap): int is too small for string size.
-
-Tue Jun 21 15:42:22 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/test_io.rb: Skip test_read_buffer_error on cygwin,
-	  because this test repeatedly hangs.
-
-Tue Jun 21 15:35:14 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* LEGAL: Added filenames and copyrights for some files in
-	  enc/trans/JIS.
-
-Tue Jun 21 00:56:47 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* win32/win32.c (get_special_folder): fix calling convention of
-	  SHGetPathFromIDListEx, which should be WINAPI.  pointed out by
-	  @arton at http://twitter.com/arton/status/744884064277016576
-
-Tue Jun 21 00:22:02 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* configure.in, include/ruby/defines.h (RUBY_USE_SETJMPEX):
-	  include setjmpex.h only when using setjmpex() for RUBY_SETJMP.
-	  the header of mingw32 overrides setjmp() by setjmpex().
-
-Mon Jun 20 18:39:16 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/test_io.rb: Skip test_open_fifo_does_not_block_other_threads
-	  on cygwin. Fifos seem to work okay in cygwin, but this test repeatedly
-	  hangs.
-
-Mon Jun 20 13:35:06 2016  Shugo Maeda  <shugo@ruby-lang.org>
-
-	* vm.c (invoke_bmethod, invoke_block_from_c_0): revert r52104
-	  partially to avoid "self has wrong type to call super in this
-	  context" errors.
-	  [ruby-core:72724] [Bug #11954]
-
-Mon Jun 20 12:53:38 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* test/rubygems/test_gem_remote_fetcher.rb: OpenSSL::PKey::DH#priv_key=
-	  is not defined when ext/openssl is built with OpenSSL 1.1.0.
-	  https://github.com/rubygems/rubygems/pull/1648
-	  [ruby-core:75225] [Feature #12324]
-
-Sun Jun 19 21:25:43 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_ocsp.c: Add OCSP::SingleResponse that represents an
-	  OCSP SingleResponse structure. Also add two new methods #responses
-	  and #find_response to OCSP::BasicResponse. A BasicResponse has one or
-	  more SingleResponse. We have OCSP::BasicResponse#status that returns
-	  them as an array of arrays, each containing the content of a
-	  SingleResponse, but this is not useful. When validating an OCSP
-	  response, we need to look into the each SingleResponse and check their
-	  validity but it is not simple. For example, when validating for a
-	  certificate 'cert', the code would be like:
-
-	    # certid_target is an OpenSSL::OCSP::CertificateId for cert
-	    basic = res.basic
-	    result = basic.status.any? do |ary|
-	      ary[0].cmp(certid_target) &&
-	        ary[4] <= Time.now && (!ary[5] || Time.now <= ary[5])
-	    end
-
-	  Adding OCSP::SingleResponse at the same time allows exposing
-	  OCSP_check_validity(). With this, the code above can be rewritten as:
-
-	    basic = res.basic
-	    single = basic.find_response(certid_target)
-	    result = single.check_validity
-
-	* test/openssl/test_ocsp.rb: Test this.
-
-Sun Jun 19 18:40:19 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_ocsp.c (ossl_ocspbres_add_status): Allow specifying
-	  the times (thisUpdate, nextUpdate and revocationTime) with Time
-	  objects. Currently they accepts only relative seconds from the current
-	  time. This is inconvenience, especially for revocationTime. When
-	  Integer is passed, they are still treated as relative times. Since the
-	  type check is currently done with rb_Integer(), this is a slightly
-	  incompatible change. Hope no one passes a relative time as String or
-	  Time object...
-	  Also, allow passing nil as nextUpdate. It is optional.
-
-	* ext/openssl/ruby_missing.h: Define RB_INTEGER_TYPE_P() if not defined.
-	  openssl gem will be released before Ruby 2.4.0.
-
-Sun Jun 19 18:39:38 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_ocsp.c: Implement OCSP::{CertificateId,Request,
-	  BasicResponse,Response}#initialize_copy.
-	  [ruby-core:75504] [Bug #12381]
-
-	* test/openssl/test_ocsp.rb: Test them.
-
-Sun Jun 19 18:29:50 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_pkey_dh.c, ext/openssl/ossl_pkey_dsa.c,
-	  ext/openssl/ossl_pkey_ec.c, ext/openssl/ossl_pkey_rsa.c: Implement
-	  initialize_copy method for OpenSSL::PKey::*.
-	  [ruby-core:75504] [Bug #12381]
-
-	* test/openssl/test_pkey_dh.rb, test/openssl/test_pkey_dsa.rb,
-	  test/openssl/test_pkey_ec.rb, test/openssl/test_pkey_rsa.rb: Test they
-	  actually copy the OpenSSL objects, and modifications to cloned object
-	  don't affect the original object.
-
-Sun Jun 19 16:55:16 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/test_dir_m17n.rb: Skip tests with non-UTF-8 encodings
-	  on cygwin. Cygwin can use the Unicode PUA (private use area) to store
-	  bytes from non-UTF-8 filenames (see
-	  https://cygwin.com/cygwin-ug-net/using-specialnames.html#pathnames-specialchars),
-	  but we are not supporting this. [Bug #12443]
-
-Sun Jun 19 15:01:18 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* localeinit.c: Fix filesystem encoding for cygwin to UTF-8 (see
-	  https://cygwin.com/cygwin-ug-net/using-specialnames.html#pathnames-unusual)
-
-Sun Jun 19 14:31:07 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_pkey.h, ext/openssl/ossl_pkey_dh.c,
-	  ext/openssl/ossl_pkey_dsa.c, ext/openssl/ossl_pkey_rsa.c: A few days
-	  ago, OpenSSL changed {DH,DSA,RSA}_get0_*() to take const BIGNUM **.
-	  https://git.openssl.org/gitweb/?p=openssl.git;a=commit;h=fd809cfdbd6e32b6b67b68c59f6d55fbed7a9327
-	  [ruby-core:75225] [Feature #12324]
-
-Sun Jun 19 11:19:43 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* variable.c (rb_path_to_class): consider the string length
-	  instead of a terminator.
-
-	* variable.c (rb_path_to_class): search the constant at once
-	  instead of checking if defined and then getting it.
-
-Sat Jun 18 14:01:40 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* test/rubygems/test_gem_installer.rb: Fixed broken test with extension
-	  build. https://github.com/rubygems/rubygems/pull/1645
-
-Sat Jun 18 13:59:54 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/rubygems.rb, lib/rubygems/*, test/rubygems/*: Update rubygems
-	  HEAD(2c6d256). It contains to update vendored Molinillo to 0.5.0.
-	  https://github.com/rubygems/rubygems/pull/1638
-
-Sat Jun 18 10:13:37 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* common.mk (build-ext), ext/extmk.rb: use variable EXTENCS
-	  different than ENCOBJS, to get rid of circular dependency.
-	  build libencs when linking encodings statically.
-	  [ruby-core:75618] [Bug #12401]
-
-Sat Jun 18 08:52:46 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/stringio/stringio.c (strio_getline): fix pointer index
-	  overflow.  reported by Guido Vranken <guido AT guidovranken.nl>.
-
-Thu Jun 16 16:35:35 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* class.c (Init_class_hierarchy): prevent rb_cObject which is the
-	  class tree root, from GC.  [ruby-dev:49666] [Bug #12492]
-
-Thu Jun 16 12:17:52 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* string.c (tr_trans): adjust buffer size by processed and rest
-	  lengths, instead of doubling repeatedly.
-
-Thu Jun 16 11:15:25 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* string.c (tr_trans): consider terminator length and fix heap
-	  overflow.  reported by Guido Vranken <guido AT guidovranken.nl>.
-
-Thu Jun 16 00:02:32 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_ocsp.c (ossl_ocspreq_verify, ossl_ocspbres_verify):
-	  Use ossl_clear_error() so that they don't print warnings to stderr and
-	  leak errors in the OpenSSL error queue. Also, check the return value
-	  of OCSP_*_verify() correctly. They can return -1 on verification
-	  failure.
-
-Wed Jun 15 19:52:23 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_ocsp.c (ossl_ocspreq_sign, ossl_ocspbres_sign): Allow
-	  specifying hash algorithm used in signing. They are hard coded to use
-	  SHA-1.
-	  Based on a patch provided by Tim Shirley <tidoublemy@gmail.com>.
-	  [ruby-core:70915] [Feature #11552] [GH ruby/openssl#28]
-
-	* test/openssl/test_ocsp.rb: Test sign-verify works.
-
-Wed Jun 15 01:46:16 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* numeric.c: [DOC] fix rdoc directive, and an example of negative
-	  value.  [ruby-core:76025] [Bug #12487]
-
-Wed Jun 15 01:44:42 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* tool/mkconfig.rb: provide Unicode Version information as
-	  RbConfig::CONFIG['UNICODE_VERSION'].
-	  [ruby-core:75845] [Feature #12460]
-
-Wed Jun 15 00:01:18 2016  Kazuhiro NISHIYAMA  <zn@mbf.nifty.com>
-
-	* test/ruby/enc/test_case_comprehensive.rb
-	  (TestComprehensiveCaseFold::read_data): use \A and \z instead of
-	  ^ and $ in regexp.
-
-Tue Jun 14 23:43:00 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/backward.h (rb_cFixnum, rb_cBignum): remove the
-	  backward compatibility macros, to fail incompatible extension
-	  libraries early.  [Bug #12427]
-
-Tue Jun 14 22:22:07 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* strftime.c (rb_strftime_with_timespec): limit the result string
-	  size by the format length, to get rid of unlimited memory use.
-
-Tue Jun 14 22:11:11 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_ocsp.c (ossl_ocspcid_get_issuer_name_hash,
-	  ossl_ocspcid_get_issuer_key_hash, ossl_ocspcid_get_hash_algorithm):
-	  Add accessor methods OCSP::CertificateId#issuer_name_hash,
-	  #issuer_key_hash, #hash_algorithm.
-	  Based on a patch provided by Paul Kehrer <paul.l.kehrer@gmail.com>.
-	  [ruby-core:48062] [Feature #7181]
-
-	* test/openssl/test_ocsp.rb: Test these new methods.
-
-Tue Jun 14 22:07:25 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/date/date_strftime.c (date_strftime_with_tmx): reject too
-	  large precision to get rid of buffer overflow.
-	  reported by Guido Vranken <guido AT guidovranken.nl>.
-
-Tue Jun 14 21:40:42 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_ocsp.c (ossl_ocspbres_to_der, ossl_ocspcid_to_der):
-	  Implement #to_der methods for OCSP::BasicResponse and
-	  OCSP::CertificateId.
-
-	  (ossl_ocspreq_initialize, ossl_ocspres_initialize): Use GetOCSP*()
-	  instead of raw DATA_PTR().
-
-	  (ossl_ocspbres_initialize, ossl_ocspcid_initialize): Allow
-	  initializing from DER string.
-
-	  (Init_ossl_ocsp): Define new #to_der methods.
-
-	* test/openssl/test_ocsp.rb: Test these changes. Also add missing tests
-	  for OCSP::{Response,Request}#to_der.
-
-Tue Jun 14 21:35:00 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/openssl_missing.h (DH_set0_pqg, RSA_set0_key):
-	  DH_set0_pqg() allows 'q' to be NULL. Fix a typo in RSA_set0_key().
-	  Fixes r55285.  [ruby-core:75225] [Feature #12324]
-
-Mon Jun 14 10:19:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* NEWS: describe Integer#digits.
-
-Mon Jun 13 21:09:40 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* thread.c (debug_deadlock_check): show thread lock dependency and
-	  backtrace [Feature #8214] [ruby-dev:47217]
-
-	* thread.c (thread_status_name): show "sleep_forever" instead of
-	  "sleep" if called from inspect.
-
-Mon Jun 13 20:50:07 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* parse.y (reg_named_capture_assign_iter): remove named capture
-	  conflict warnings.  it is just annoying rather than useful.
-	  [ruby-core:75416] [Bug #12359]
-
-Mon Jun 13 20:04:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* numeric.c (rb_int_digits, rb_fix_digits, rb_int_digits_bigbase):
-	  Add Integer#digits to extract columns in place-value notation
-	  [Feature #12447] [ruby-core:75799]
-
-	* test/ruby/test_integer.rb: Add tests for the above change.
-
-	* test/ruby/test_bignum.rb: ditto.
-
-Mon Jun 13 20:34:53 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/ruby.h (RUBY_INTEGER_UNIFICATION): macro to tell if
-	  Integer is integrated.  [ruby-core:75718][Bug #12427]
-
-	* include/ruby/backward.h, internal.h (rb_cFixnum, rb_cBignum):
-	  fallback to rb_cInteger.
-
-	* bignum.c, numeric.c, ext/json/generator/generator.{c,h}: use the
-	  macro.
-
-Mon Jun 13 16:58:53 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_comprehensive.rb: Add tests for full Unicode
-	  swapcase.
-
-Sun Jun 12 14:48:00 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_comprehensive.rb: Add tests for ASCII-only
-	  swapcase; store calculated values in hashes.
-
-Sun Jun 12 14:05:45 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_cipher.c (ossl_cipher_get_auth_tag,
-	  ossl_cipher_set_auth_tag): Check if the cipher flags retrieved by
-	  EVP_CIPHER_CTX_flags() includes EVP_CIPH_FLAG_AEAD_CIPHER to see if
-	  the cipher supports AEAD. AES-GCM was the only supported in OpenSSL
-	  1.0.1.
-
-	  (Init_ossl_cipher): Fix doc; OpenSSL::Cipher::AES.new(128, :GCM) can't
-	  work.
-
-	* ext/openssl/openssl_missing.h: Define EVP_CTRL_AEAD_{GET,SET}_TAG if
-	  missing. They are added in OpenSSL 1.1.0, and have the same value as
-	  EVP_CTRL_GCM_{GET,SET}_TAG and EVP_CTRL_CCM_{GET,SET}_TAG.
-
-Sun Jun 12 13:47:42 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* test/openssl/test_engine.rb (test_openssl_engine_builtin,
-	  test_openssl_engine_by_id_string): Skip test if 'openssl' engine is
-	  already loaded. And test the number increased by Engine.load{_by_id,},
-	  not the total count of loaded engines. Previously, we called
-	  OpenSSL::Engine.cleanup every time running a test case, but we no
-	  longer can do it.
-	  [ruby-core:75225] [Feature #12324]
-
-Sun Jun 12 09:24:34 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* file.c (append_fspath): normalize directory name to be appended
-	  on OS X.  [ruby-core:75957] [Ruby trunk Bug#12483]
-	  https://github.com/rails/rails/issues/25303#issuecomment-224834804
-
-Sat Jun 11 23:07:32 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* lib/forwardable.rb (_delegator_method): get rid of a warning which
-	  causes test failures introduced at r55376.
-
-Sat Jun 11 18:37:58 2016  Marcus Stollsteimer  <sto.mar@web.de>
-
-	* ext/json/lib/*.rb: Removed some comments. Because these are unnecessary
-	  class description. [ci skip][Bug #12255][ruby-core:74835]
-
-Sat Jun 11 15:19:38 2016  takiy33  <takiy33@users.noreply.github.com>
-
-	* lib/net/smtp.rb: [DOC] Remove dead link on documentation for
-	  Japanese of SMTP.  [Fix GH-1380]
-
-Sat Jun 11 15:02:45 2016  Grant Hutchins  <github@nertzy.com>
-
-	* string.c (rb_str_oct): [DOC] fix typo, hornored -> honored.
-	  [Fix GH-1379]
-
-Sat Jun 11 14:04:19 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/objspace/objspace_dump.c: generate valid JSON for dump_all.
-
-Sat Jun 11 13:52:33 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/forwardable.rb (_delegator_method): remove __send__ call if
-	  possible, so that more optimizations will be enabled.
-
-Sat Jun 11 11:24:36 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* enc/iso_8859.h (SHARP_s): name frequently used codepoint.
-
-Sat Jun 11 09:58:45 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_1.c: Revert to older version of code.
-
-Sat Jun 11 09:46:17 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/iso_8859_1.c: Implement non-ASCII case mapping.
-
-	* test/ruby/enc/test_case_comprehensive.rb: Tests for above.
-
-	* string.c: Add iso-8859-1 to supported encodings.
-
-Sat Jun 11 09:31:28 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/forwardable.rb (_delegator_method): leave the backtrace
-	  untouched during accessor.  forwardable.rb does not appear in
-	  the backtrace during delegated method because of tail-call
-	  optimization.
-
-Sat Jun 11 01:38:31 2016  Naohisa Goto  <ngotogenome@gmail.com>
-
-	* include/ruby/defines.h (GCC_VERSION_SINCE): Fix logic error by
-	  adding parentheses. Fix failures of TestMkmf::TestConvertible
-	  with GCC 3.4.3 on Solaris 10. [Bug #12479] [ruby-dev:49660]
-
-Fri Jun 10 21:54:24 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/forwardable.rb (Forwardable._delegator_method): extract
-	  method generator and deal with non-module objects.
-	  [ruby-dev:49656] [Bug #12478]
-
-Fri Jun 10 17:35:11 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c: Special-case :ascii option in rb_str_capitalize_bang and
-	  rb_str_swapcase_bang.
-
-Fri Jun 10 17:12:24 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c: Special-case :ascii option in rb_str_upcase_bang (retry).
-
-Fri Jun 10 14:48:36 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* hash.c (get_env_cstr): ensure NUL-terminated.
-	  [ruby-dev:49655] [Bug #12475]
-
-	* string.c (rb_str_fill_terminator): return the pointer to the
-	  NUL-terminated content.
-
-Thu Jun  9 21:42:00 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_asn1.c (asn1integer_to_num): Use
-	  ASN1_ENUMERATED_to_BN() to convert an ASN1_ENUMERATED to a BN.
-	  Starting from OpenSSL 1.1.0, ASN1_INTEGER_to_BN() rejects
-	  non-ASN1_INTEGER objects. The format of INTEGER and ENUMERATED are
-	  almost identical so they behaved in the same way in OpenSSL <= 1.0.2.
-	  [ruby-core:75225] [Feature #12324]
-
-	* test/openssl/test_asn1.rb (test_decode_enumerated): Test that it
-	  works.
-
-Thu Jun  9 21:10:04 2016  Kazuhiro NISHIYAMA  <zn@mbf.nifty.com>
-
-	* tool/ifchange: fix timestamp error when target without
-	  directory.
-
-Thu Jun  9 19:46:22 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_ssl.c: Add define guards for OPENSSL_NO_EC.
-	  SSL_CTX_set_ecdh_auto() is defined even when ECDH is disabled in
-	  OpenSSL's configuration. This fixes r55214.
-
-	* test/openssl/test_pair.rb (test_ecdh_curves): Skip if the OpenSSL does
-	  not support ECDH.
-
-	* test/openssl/utils.rb (start_server): Ignore error in
-	  SSLContext#ecdh_curves=.
-
-Thu Jun  9 18:12:42 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* Makefile.in (un-runnable): fail with proper error message.
-	  [ruby-core:75905] [Bug #12472]
-
-Thu Jun  9 15:32:17 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* common.mk (RBCONFIG): use ifchange tool to see if the content is
-	  changed and update the timestamp file.
-
-	* tool/mkconfig.rb: remove ifchange features.
-
-	* tool/ifchange: make target directory if it does not exist with
-	  its parent directories.
-
-	* win32/ifchange.bat: drop support for command.com used on old
-	  systems.
-
-Thu Jun  9 15:03:35 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/extconf.rb: Check for CRYPTO_malloc() and SSL_new().
-	  OpenSSL_add_all_digests() and SSL_library_init() are deprecated and
-	  converted to macros in OpenSSL 1.1.0.
-	  [ruby-core:75225] [Feature #12324]
-
-Wed Jun  8 23:09:51 2016  Kazuhiro NISHIYAMA  <zn@mbf.nifty.com>
-
-	* string.c (rb_str_ascii_casemap): fix compile error.
-
-Wed Jun  8 22:22:24 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c: Revert previous commit (possibility of endless loop).
-
-Wed Jun  8 21:57:41 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c: Special-case :ascii option in rb_str_upcase_bang.
-
-Wed Jun  8 21:28:36 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c: New static function rb_str_ascii_casemap; special-casing
-	  :ascii option in rb_str_upcase_bang and rb_str_downcase_bang.
-
-	* regenc.c: Fix a bug (wrong use of unnecessary slack at end of string).
-
-	* regenc.h -> include/ruby/oniguruma.h: Move declaration of
-	  onigenc_ascii_only_case_map so that it is visible in string.c.
-
-Wed Jun  8 20:33:44 2016  Naohisa Goto  <ngotogenome@gmail.com>
-
-	* include/ruby/intern.h: Remove excess semicolons in PUREFUNC().
-	  Fix failure of TestMkmf::TestConvertible on Solaris with
-	  Oracle Solaris Studio 12. [ruby-dev:49651] [Bug #12470]
-	* internal.h: ditto.
-
-Wed Jun  8 16:03:09 2016  Shugo Maeda  <shugo@ruby-lang.org>
-
-	* lib/net/smtp.rb (getok, get_response): raise an ArgumentError when
-	  CR or LF is included in a line, because they are not allowed in
-	  RFC5321.  Thanks, Jeremy Daer.
-
-Tue Jun  7 21:27:25 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* test/rubygems/*_{cert,cert_32}.pem: Regenerate test certificates for
-	  OpenSSL 1.1.0. This is already in upstream.
-	  https://github.com/rubygems/rubygems/commit/9be5c53939440a61c4bba73cfffbeb5cfadf72be
-	  [ruby-core:75225] [Feature #12324]
-
-Tue Jun  7 21:27:17 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* test/open-uri/test_ssl.rb: Regenerate test certificates. The test CA
-	  certificate was incorrectly generated. A CA certificate must have the
-	  basic constraints extension with cA bit set to TRUE. OpenSSL <= 1.0.2
-	  allowed the error when the certificate is in the trusted store but
-	  OpenSSL 1.1.0 no longer does.
-	  [ruby-core:75225] [Feature #12324]
-
-Tue Jun  7 21:20:38 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* test/openssl/test_x509name.rb: Don't register OID for 'emailAddress'
-	  and 'serialNumber'. A recent change in OpenSSL made OBJ_create()
-	  reject an already existing OID. They were needed to run tests with
-	  OpenSSL 0.9.6 which is now unsupported.
-	  https://git.openssl.org/gitweb/?p=openssl.git;a=commit;h=52832e470f5fe8c222249ae5b539aeb3c74cdb25
-	  [ruby-core:75225] [Feature #12324]
-
-	* test/openssl/test_ssl_session.rb (test_server_session): Duplicate
-	  SSL::Session before re-adding to the session store. OpenSSL 1.1.0
-	  starts rejecting SSL_SESSION once removed by SSL_CTX_remove_session().
-	  https://git.openssl.org/gitweb/?p=openssl.git;a=commit;h=7c2d4fee2547650102cd16d23f8125b76112ae75
-
-	* test/openssl/test_pkey_ec.rb (setup): Remove X25519 from @keys. X25519
-	  is new in OpenSSL 1.1.0 but this is for key agreement and not for
-	  signing.
-
-	* test/openssl/test_pair.rb, test/openssl/test_ssl.rb,
-	  test/openssl/utils.rb: Set security level to 0 when using aNULL cipher
-	  suites.
-
-	* test/openssl/utils.rb: Use 1024 bits DSA key for client certificates.
-
-	* test/openssl/test_engine.rb: Run each test in separate process.
-	  We can no longer cleanup engines explicitly as ENGINE_cleanup() was
-	  removed.
-	  https://git.openssl.org/gitweb/?p=openssl.git;a=commit;h=6d4fb1d59e61aacefa25edc4fe5acfe1ac93f743
-
-	* ext/openssl/ossl_engine.c (ossl_engine_s_cleanup): Add a note to the
-	  RDoc for Engine.cleanup.
-
-	* ext/openssl/lib/openssl/digest.rb: Don't define constants for DSS,
-	  DSS1 and SHA(-0) when using with OpenSSL 1.1.0. They are removed.
-
-	* test/openssl/test_digest.rb, test/openssl/test_pkey_dsa.rb,
-	  test/openssl/test_pkey_dsa.rb, test/openssl/test_ssl.rb,
-	  test/openssl/test_x509cert.rb, test/openssl/test_x509req.rb: Don't
-	  test unsupported hash functions.
-
-Tue Jun  7 17:49:52 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_comprehensive: Change test for encodings
-	  without any non-ASCII case conversions from ASCII-only test
-	  to full test.
-
-Tue Jun  7 17:18:39 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c (rb_str_upcase_bang, rb_str_capitalize_bang,
-	  rb_str_swapcase_bang): Switch to use primitive.
-
-Tue Jun  7 16:44:16 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c (rb_str_downcase_bang): Switch to use primitive except if
-	  conversion can be done ASCII-only.
-
-Tue Jun  7 16:13:36 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_comprehensive: Add regression tests for
-	  current ASCII-only case conversion.
-
-Tue Jun  7 15:28:38 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_comprehensive: Fix method name
-	  (generate_casefold_tests -> generate_case_mapping_tests).
-
-Tue Jun  7 15:05:13 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* regenc.h/c: Rename onigenc_not_support_case_map to
-	  onigenc_ascii_only_case_map.
-
-	* regenc.h: Add definition of onigenc_single_byte_ascii_only_case_map.
-
-	* enc/iso_8859_X.c, windows_125X.c, ascii.c, us-ascii.c, koi8_x.c:
-	  Replace onigenc_not_support_case_map by
-	  onigenc_single_byte_ascii_only_case_map.
-
-	* enc/big5.c, cp949.c, emacs_mule.c, euc_X.c, gbX.c, shift_jis.c,
-	  windows_31j.c: Replace onigenc_not_support_case_map by
-	  onigenc_ascii_only_case_map.
-
-Tue Jun  7 14:57:09 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/extconf.rb: Check for SSL_CTX_set_min_proto_version()
-	  macro added in OpenSSL 1.1.0. Version-specific methods, such as
-	  TLSv1_method(), are deprecated in OpenSSL 1.1.0. We need to use
-	  version-flexible methods (TLS_*method() or SSLv23_*method()) and
-	  disable other protocol versions as necessary.
-	  [ruby-core:75225] [Feature #12324]
-
-	* ext/openssl/ossl_ssl.c: Use SSL_CTX_set_{min,max}_proto_version() to
-	  fix the protocol version.
-
-Tue Jun  7 12:55:34 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* regenc.c (onigenc_not_support_case_map): Move to end of file;
-	  (onigenc_single_byte_ascii_only_case_map): Add new function.
-
-Tue Jun  7 09:26:37 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* regenc.c (onigenc_not_support_case_map): Rewrite to work correctly
-	  in ASCII range.
-
-Mon Jun  6 23:00:00 2016  Kazuhiro NISHIYAMA  <zn@mbf.nifty.com>
-
-	* appveyor.yml: Update libressl version to 2.3.5.
-
-Mon Jun  6 18:37:57 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* vm_insnhelper.c (vm_throw_start): check if the iseq is symbol
-	  proc, class definition should not be a symbol proc.
-	  [ruby-core:75856] [Bug #12462]
-
-Mon Jun  6 18:36:34 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c: Added UTF-16BE/LE and UTF-32BE/LE to supported encodings
-	  for Unicode case mapping.
-
-	* test/ruby/enc/test_case_comprehensive.rb: Tests for above
-	  functionality; fixed an encoding issue in assertion error message.
-
-Mon Jun  6 17:29:35 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_comprehensive.rb: Speed up testing for small
-	  encodings by preselecting codepoints.
-
-Mon Jun  6 17:10:50 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_cipher.c (ossl_cipher_free): Use EVP_CIPHER_CTX_free()
-	  to free EVP_CIPHER_CTX allocated by EVP_CIPHER_CTX_new().
-	  [ruby-core:75225] [Feature #12324]
-
-Mon Jun  6 13:37:08 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c Change rb_str_casemap to use encoding primitive
-	  case_map instead of directly calling onigenc_unicode_case_map.
-
-Mon Jun  6 13:16:46 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_mapping.rb:
-	  Remove :lithuanian guard for Unicode case mapping.
-
-Mon Jun  6 10:39:56 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/openssl_missing.h: Include ruby/config.h. r55285 added
-	  some inline functions but VC does not recognize 'inline' keyword.
-
-Mon Jun  6 09:25:34 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* thread.c (thread_start_func_2): report raised exception if
-	  report_on_exception flag is set.  [Feature #6647]
-
-Mon Jun  6 01:36:24 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/extconf.rb: Check existence of SSL_is_server(). This
-	  function was introduced in OpenSSL 1.0.2.
-	  [ruby-core:75225] [Feature #12324]
-
-	* ext/openssl/openssl_missing.h: Implement SSL_is_server() if missing.
-
-	* ext/openssl/ossl_ssl.c (ssl_info_cb): Use SSL_is_server() to see if
-	  the SSL is server. The state machine in OpenSSL was rewritten and
-	  SSL_get_state() no longer returns SSL_ST_ACCEPT.
-
-	  (ossl_ssl_cipher_to_ary, ossl_sslctx_session_get_cb): Add some
-	  `const`s to suppress warning.
-
-Mon Jun  6 01:18:10 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_asn1.c (decode_bool): Do the same thing as
-	  d2i_ASN1_BOOLEAN() does by ourselves. This function is removed in
-	  OpenSSL 1.1.0.
-	  [ruby-core:75225] [Feature #12324]
-
-Mon Jun  6 00:34:16 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/extconf.rb: Check existence of accessor functions that
-	  don't exist in OpenSSL 0.9.8. OpenSSL 1.1.0 made most of its
-	  structures opaque and requires use of these accessor functions.
-	  [ruby-core:75225] [Feature #12324]
-
-	* ext/openssl/openssl_missing.[ch]: Implement them if missing.
-
-	* ext/openssl/ossl*.c: Use these accessor functions.
-
-	* test/openssl/test_hmac.rb: Add missing test for HMAC#reset.
-
-Mon Jun  6 00:00:13 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/openssl_missing.[ch]: Implement EVP_PKEY_get0_*() and
-	  {RSA,DSA,EC_KEY,DH}_get0_*() functions.
-	  OpenSSL 1.1.0 makes EVP_PKEY/RSA/DSA/DH opaque. We used to provide
-	  setter methods for each parameter of each PKey type, for example
-	  PKey::RSA#e=, but this is no longer possible because the new API
-	  RSA_set0_key() requires the 'n' at the same time. This commit adds
-	  deprecation warning to them and adds PKey::*#set_* methods as direct
-	  wrapper for those new APIs. For example, 'rsa.e = 3' now needs to be
-	  rewritten as 'rsa.set_key(rsa.n, 3, rsa.d)'.
-	  [ruby-core:75225] [Feature #12324]
-
-	* ext/openssl/ossl_pkey*.[ch]: Use the new accessor functions. Implement
-	  RSA#set_{key,factors,crt_params}, DSA#set_{key,pqg}, DH#set_{key,pqg}.
-	  Emit a warning with rb_warning() when old setter methods are used.
-
-	* test/drb/ut_array_drbssl.rb, test/drb/ut_drb_drbssl.rb,
-	  test/rubygems/test_gem_remote_fetcher.rb: Don't set a priv_key for DH
-	  object that are used in tmp_dh_callback. Generating a new key pair
-	  every time should be fine - actually the private exponent is ignored
-	  in OpenSSL >= 1.0.2f/1.0.1r even if we explicitly set.
-	  https://www.openssl.org/news/secadv/20160128.txt
-
-Sun Jun  5 22:06:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* configure.in: Fix the timing to detect the appropriate C++ compiler
-	  in OS X.
-
-Sun Jun  5 21:42:24 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/extconf.rb: Check absence of CRYPTO_lock() to see if the
-	  OpenSSL has the new threading API. In OpenSSL <= 1.0.2, an application
-	  had to set locking callbacks to use OpenSSL in a multi-threaded
-	  environment. OpenSSL 1.1.0 now finds pthreads or Windows threads so we
-	  don't need to do something special.
-	  [ruby-core:75225] [Feature #12324]
-
-	  Also check existence of *_up_ref(). Some structures in OpenSSL have
-	  a reference counter. We used to increment it with CRYPTO_add() which
-	  is a part of the old API.
-
-	* ext/openssl/openssl_missing.h: Implement *_up_ref() if missing.
-
-	* ext/openssl/ossl.c: Don't set locking callbacks if unneeded.
-
-	* ext/openssl/ossl_pkey.c, ext/openssl/ossl_ssl.c,
-	  ext/openssl/ossl_x509cert.c, ext/openssl/ossl_x509crl.c,
-	  ext/openssl/ossl_x509store.c: Use *_up_ref() instead of CRYPTO_add().
-
-Sun Jun  5 21:38:13 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/extconf.rb: Check if RAND_pseudo_bytes() is usable. It is
-	  marked as deprecated in OpenSSL 1.1.0.
-	  [ruby-core:75225] [Feature #12324]
-
-	* ext/openssl/ossl_rand.c: Disable Random.pseudo_bytes if
-	  RAND_pseudo_bytes() is unavailable.
-
-	* test/openssl/test_random.rb: Don't test Random.pseudo_bytes if not
-	  defined.
-
-Sun Jun  5 19:06:40 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* NEWS: Add news about Unicode-wide case mapping for
-	  String/Symbol#upcase/downcase/swapcase/capitalize(!).
-
-Sun Jun  5 15:24:33 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_comprehensive.rb:
-	  Remove :lithuanian guard for Unicode case mapping.
-
-Sun Jun  5 14:46:34 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c: Remove :lithuanian guard for Unicode case mapping.
-
-Sat Jun  4 10:54:52 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* missing/crypt.h (struct crypt_data): remove unnecessary member
-	  "initialized".
-
-	* missing/crypt.c (des_setkey_r): nothing to be initialized in
-	  crypt_data.
-
-	* configure.in (struct crypt_data): check for "initialized" in
-	  struct crypt_data, which may be only in glibc, and isn't on AIX
-	  at least.
-
-Sat Jun  4 10:38:39 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* win32/win32.c: unify MAX_PATH, _MAX_PATH, and MAXPATHLEN to
-	  PATH_MAX, except for MAX_PATH in get_special_folder for an API
-	  limit.
-
-Fri Jun  3 21:27:22 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ruby.c (process_options): rb_str_conv_enc() never set encoding
-	  of the source string, but returns the string itself if the
-	  conversion failed.  then the instance variable does not need to
-	  be set again.
-
-Fri Jun  3 18:04:37 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* ruby.c (process_options): need to duplicate path before passing it to
-	  rb_str_conv_enc() because the function might call rb_enc_associate()
-	  internally.  this fixes test failures on Windows introduced at r55260.
-
-Fri Jun  3 17:44:25 2016  Reiner Herrmann  <reiner@reiner-h.de>
-
-	* lib/mkmf.rb (create_makefile): sort lists of source and object
-	  files in generated Makefile, unless given by extconf.rb.
-	  [Fix GH-1367]
-
-Thu Jun  2 21:18:10 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* win32/win32.c (get_special_folder): use SHGetPathFromIDListEx if
-	  available instead of old SHGetPathFromIDListW, to check the
-	  buffer size.
-
-Thu Jun  2 17:05:19 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ruby.c (ruby_init_loadpath_safe): remove MAXPATHLEN restriction
-	  for Windows 10.
-
-Thu Jun  2 16:51:35 2016  Koichi ITO  <koic.ito@gmail.com>
-
-	* misc/ruby-mode.el (ruby-here-doc-beg-re),
-	  (ruby-here-doc-beg-match, ruby-parse-partial): Support for
-	  `squiggly heredoc' syntax in ruby-mode.  [Fix GH-1372]
-
-Thu Jun  2 10:24:48 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c: Raise ArgumentError when invalid string is detected in
-	  case mapping methods.
-
-	* enc/unicode.c: Check for invalid string and signal with negative
-	  length value.
-
-	* test/ruby/enc/test_case_mapping.rb: Add tests for above.
-
-	* test/ruby/test_m17n_comb.rb: Add a message to clarify test failure.
-
-Wed Jun  1 21:41:05 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/extconf.rb: Check existence of ASN1_TIME_adj(). The old
-	  ASN1_TIME_set() is not Year 2038 ready on sizeof(time_t) == 4
-	  environment. This function was added in OpenSSL 1.0.0.
-	  [ruby-core:45552] [Bug #6571]
-
-	* ext/openssl/ossl_asn1.c (ossl_time_split): Added. Split the argument
-	  (Time) into the number of days elapsed since the epoch and the
-	  remainder seconds to conform to ASN1_TIME_adj().
-	  (obj_to_asn1utime, obj_to_asn1gtime): Use ossl_time_split() and
-	  ASN1_*TIME_adj().
-
-	* ext/openssl/ossl_asn1.h: Add the function prototype for
-	  ossl_time_split().
-
-	* ext/openssl/ossl_x509.[ch]: Add ossl_x509_time_adjust(). Similarly to
-	  obj_to_asn1*time(), use X509_time_adj_ex() instead of X509_time_adj().
-
-	* ext/openssl/ossl_x509cert.c, ext/openssl/ossl_x509crl.c,
-	  ext/openssl/ossl_x509revoked.c: Use ossl_x509_time_adjust().
-
-Wed Jun  1 15:58:20 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* configure.in: revert r55237.  replace crypt, not crypt_r, and
-	  check if crypt is broken more.
-
-	* missing/crypt.c: move crypt_r.c
-
-	* string.c (rb_str_crypt): use crypt_r if provided by the system.
-
-Wed Jun  1 14:07:53 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* missing/crypt_r.c (a64toi): initialize statically and fix out of
-	  bounds access when salt is not 7bit clean.
-
-Wed Jun  1 11:34:59 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* win32/Makefile.sub (MISSING): fixed build error introduced at r55237.
-
-Wed Jun  1 09:48:06 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* string.c (rb_str_crypt): use reentrant crypt_r.
-
-Wed Jun  1 09:37:26 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* missing/crypt.c (des_setkey): void function never returns any value.
-
-Wed Jun  1 09:16:22 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* crypt.h: separate header file from missing/crypt.c.
-
-	* missing/crypt.c (crypt_r, setkey_r, encrypt_r): add reentrant
-	  versions.
-
-Wed Jun  1 02:25:38 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* missing/crypt.c: fix size macros to use configured values
-	  for platforms long is larger than 32bit.
-	  [ruby-core:75792] [Bug #12446]
-
-Tue May 31 17:28:46 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/optparse.rb (OptionParser::Completion.candidate): get rid of
-	  nil as key names.  [ruby-core:75773] [Bug #12438]
-
-	* lib/optparse.rb (OptionParser#make_switch): char class option
-	  cannot be NoArgument, default to RequiredArgument.
-
-Tue May 31 00:30:11 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* ext/socket/raddrinfo.c (host_str, port_str): Use StringValueCStr
-	  instead of (Safe)StringValue, to detect NUL byte in the string.
-
-Mon May 30 22:02:01 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_asn1.c (time_to_time_t): Use NUM2TIMET() instead of
-	  NUM2LONG(). time_t may be larger than long.
-	  [ruby-core:45552] [Bug #6571]
-
-Mon May 30 21:15:37 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c: Document current behavior for other case mapping methods
-	  on String. [ci skip]
-
-Mon May 30 20:00:25 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c: Document current situation for String#downcase. [ci skip]
-
-Mon May 30 18:29:28 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_ssl.c (ossl_sslctx_s_alloc): Enable the automatic
-	  curve selection for ECDH by calling SSL_CTX_set_ecdh_auto(). With
-	  this a TLS server automatically selects a curve which both the client
-	  and the server support to use in ECDH. This changes the default
-	  behavior but users can still disable ECDH by excluding 'ECDH' cipher
-	  suites from the cipher list (with SSLContext#ciphers=). This commit
-	  also deprecate #tmp_ecdh_callback=. It was added in Ruby 2.3.0. It
-	  wraps SSL_CTX_set_tmp_ecdh_callback() which will be removed in OpenSSL
-	  1.1.0. Its callback receives two values 'is_export' and 'keylength'
-	  but both are completely useless for determining a curve to use in
-	  ECDH. The automatic curve selection was introduced to replace this.
-
-	  (ossl_sslctx_setup): Deprecate SSLContext#tmp_ecdh_callback=. Emit a
-	  warning if this is in use.
-
-	  (ossl_sslctx_set_ecdh_curves): Add SSLContext#ecdh_curves=. Wrap
-	  SSL_CTX_set1_curves_list(). If it is not available, this falls back
-	  to SSL_CTX_set_tmp_ecdh().
-
-	  (Init_ossl_ssl): Define SSLContext#ecdh_curves=.
-
-	* ext/openssl/extconf.rb: Check the existence of EC_curve_nist2nid(),
-	  SSL_CTX_set1_curves_list(), SSL_CTX_set_ecdh_auto() and
-	  SSL_CTX_set_tmp_ecdh_callback().
-
-	* ext/openssl/openssl_missing.[ch]: Implement EC_curve_nist2nid() if
-	  missing.
-
-	* test/openssl/test_pair.rb (test_ecdh_callback): Use
-	  EnvUtil.suppress_warning to suppress deprecated warning.
-
-	  (test_ecdh_curves): Test that SSLContext#ecdh_curves= works.
-
-	* test/openssl/utils.rb (start_server): Use SSLContext#ecdh_curves=.
-
-Mon May 30 16:28:53 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/socket/raddrinfo.c (host_str, port_str): use RSTRING_LEN
-	  instead of strlen, since RSTRING_PTR StringValueCStr may not be
-	  NUL-terminated when SHARABLE_MIDDLE_SUBSTRING=1.  reported by
-	  @tmtms, http://twitter.com/tmtms/status/736910516229005312
-
-Mon May 30 16:20:26 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* string.c (str_fill_term): return new pointer reallocated by
-	  filling terminator.
-
-Mon May 30 14:54:58 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/stringio/stringio.c (enc_subseq): share the return value and
-	  the buffer as possible.
-
-Mon May 30 14:50:25 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* string.c (str_substr, rb_str_aref): refactor not to create
-	  unnecessary empty string.
-
-	* string.c (str_byte_substr, str_byte_aref): ditto.
-
-Mon May 30 00:09:37 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* ext/-test-/auto_ext.rb: fixed a heedless bug introduced at r55198.
-	  this change will make RubyCI green.
-
-Sun May 29 22:58:19 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* regexec.c (ONIGENC_IS_MBC_ASCII_WORD): redefine optimized one.
-	  WORD of Ruby's ascii compatible encoding is always [a-zA-Z0-9_].
-
-Sun May 29 22:44:19 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* regexec.c (match_at): make compilers optimize harder.
-
-Sun May 29 12:08:42 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/-test-/auto_ext.rb (auto_ext): utility method to create
-	  extension libraries for tests.
-
-Sat May 28 20:40:57 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* misc/ruby-additional.el (ruby-insert-heredoc-code-block): insert
-	  here document code block for assert_separately mainly.
-
-Sat May 28 20:34:19 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/test_unicode_normalize.rb: Add test to check for availability of
-	  Unicode data file; refactoring; fix an error with tests for destructive
-	  method (unicode_normalize!).
-
-Sat May 28 19:08:36 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_comprehensive.rb: Add error messages to tests
-	  for data file availability; refactoring.
-
-Sat May 28 14:00:10 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/lib/openssl/ssl.rb (SSLSocket): Move the implementation of
-	  SSLSocket#initialize to C. Initialize the SSL (OpenSSL object) in it.
-	  Currently this is delayed until ossl_ssl_setup(), which is called from
-	  SSLSocket#accept or #connect. Say we call SSLSocket#hostname= with an
-	  illegal value. We expect an exception to be raised in #hostname= but
-	  actually we get it in the later SSLSocket#connect. Because the SSL is
-	  not ready at #hostname=, the actual call of SSL_set_tlsext_host_name()
-	  is also delayed.
-	  This also fixes: [ruby-dev:49376] [Bug #11724]
-
-	* ext/openssl/ossl_ssl.c (ossl_ssl_initialize): Added. Almost the same
-	  as the Ruby version but this instantiate the SSL object at the same
-	  time.
-
-	  (ossl_ssl_setup): Adjust to the changes. Just set the underlying IO to
-	  the SSL.
-
-	  (ssl_started): Added. Make use of SSL_get_fd(). This returns -1 if not
-	  yet set by SSL_set_fd().
-
-	  (ossl_ssl_data_get_struct): Removed. Now GetSSL() checks that the SSL
-	  exists.
-
-	  (ossl_ssl_set_session): Don't call ossl_ssl_setup() here as now the
-	  SSL is already instantiated in #initialize.
-
-	  (ossl_ssl_shutdown, ossl_start_ssl, ossl_ssl_read_internal,
-	   ossl_ssl_write_internal, ossl_ssl_stop, ossl_ssl_get_cert,
-	   ossl_ssl_get_peer_cert, ossl_ssl_get_peer_cert_chain,
-	   ossl_ssl_get_version, ossl_ssl_get_cipher, ossl_ssl_get_state,
-	   ossl_ssl_pending, ossl_ssl_session_reused,
-	   ossl_ssl_get_verify_result, ossl_ssl_get_client_ca_list,
-	   ossl_ssl_npn_protocol, ossl_ssl_alpn_protocol, ossl_ssl_tmp_key): Use
-	  GetSSL() instead of ossl_ssl_data_get_struct(). Use ssl_started().
-
-	  (Init_ossl_ssl): Add method declarations of SSLSocket#{initialize,
-	  hostname=}.
-
-	* ext/openssl/ossl_ssl.h (GetSSL): Check that the SSL is not NULL. It
-	  should not be NULL because we now set it in #initialize.
-
-	* ext/openssl/ossl_ssl_session.c (ossl_ssl_session_initialize): No need
-	  to check if the SSL is NULL.
-
-Sat May 28 10:47:40 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* gems/bundled_gems: Update latest releases, power_assert-0.3.0,
-	  test-unit 3.1.9, minitest 5.9.0, did_you_mean 1.0.1
-
-Sat May 28 10:45:40 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* addr2line.c: drop support for ATARI ST platform. It was
-	  discontinued more than two decades ago. [fix GH-1350] Patch by
-	  @cremno
-	* include/ruby/ruby.h: ditto.
-	* io.c: ditto.
-
-Sat May 28 10:39:47 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_comprehensive.rb: Converted exception for
-	  unavailable Unicode data files to failed assertion.
-
-Sat May 28 10:26:18 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/cgi/util.rb: added missing quote.
-	  [fix GH-1363][ci skip] Patch by @dwaller
-
-Fri May 27 17:38:49 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* variable.c (rb_local_constants_i): exclude hidden constants.
-	  [ruby-core:75575] [Bug #12389]
-
-Fri May 27 17:09:44 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* transcode.c (str_transcode0): scrub in the given encoding when
-	  the source encoding is given, not in the encoding of the
-	  receiver.  [ruby-core:75732] [Bug #12431]
-
-Fri May 27 15:07:32 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/ruby.h (rb_scan_args): remove nul padding which
-	  caused syntax error if fmt is not a string literal.
-
-	* include/ruby/ruby.h (rb_scan_args_verify): suppress array-bounds
-	  warnings by old clang.
-
-	* include/ruby/ruby.h (rb_scan_args0): make extractor macros
-	  inline functions, which do not validate the format and are
-	  unnecessary to be expanded.
-
-Fri May 27 01:00:36 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* symbol.c (is_identchar): use ISDIGIT instead of rb_enc_isalnum.
-	  Though rb_enc_isalnum is encoding aware function, its argument here
-	  is *m, which is a single byte. Therefore ISDIGIT is faster.
-
-	* symbol.c (is_special_global_name): ditto.
-
-	* symbol.c (rb_enc_symname_type): ditto.
-
-Fri May 27 00:39:40 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/ruby.h (rb_scan_args): add nul padding here to
-	  apply to all references.
-
-	* include/ruby/ruby.h (rb_scan_args_verify): move length mismatch
-	  check outside conditional operators.
-
-Thu May 26 14:21:10 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_pkey_dh.c (ossl_dh_compute_key): Check that the DH
-	  has 'p' (the prime) before calling DH_size(). We can create a DH with
-	  no parameter but DH_size() does not check and dereferences NULL.
-	  [ruby-core:75720] [Bug #12428]
-
-	* ext/openssl/ossl_pkey_dsa.c (ossl_dsa_sign): Ditto. DSA_size() does
-	  not check dsa->q.
-
-	* ext/openssl/ossl_pkey_rsa.c (ossl_rsa_public_encrypt,
-	  ossl_rsa_public_decrypt, ossl_rsa_private_encrypt,
-	  ossl_rsa_private_decrypt): Ditto. RSA_size() does not check rsa->n.
-
-Thu May 26 14:13:52 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/ruby.h (rb_scan_args_count): verify length with
-	  counting variables together.
-
-Thu May 26 09:45:41 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_comprehensive.rb: Add set of comprehensive
-	  (across most Unicode characters; later across most character encodings)
-	  tests for case mapping.
-
-Thu May 26 05:00:13 2016  Benoit Daloze  <eregontp@gmail.com>
-
-	* class.c (rb_define_class): Fix documentation.
-
-Wed May 25 20:50:12 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* re.c (unescape_nonascii): scan hex up to only 3 characters.
-	  [Bug #12420] [Bug #12423]
-
-Wed May 25 19:07:19 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Handle DOTLESS_i by hand because it isn't involved in folding.
-
-Wed May 25 18:30:53 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* regparse.c (fetch_token_in_cc): raise error if given octal escaped
-	  character is too big. [Bug #12420] [Bug #12423]
-
-Wed May 25 17:45:15 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl, test/openssl: Drop OpenSSL < 0.9.8 support.
-
-Wed May 25 17:43:30 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/openssl_missing.h, ext/openssl/ossl.h: Remove
-	  unnecessary 'extern "C"' blocks. We don't use C++ and these headers
-	  are local to ext/openssl, so there is no need to enclose with it.
-
-Wed May 25 17:42:58 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/extconf.rb: Remove check of OPENSSL_FIPS macro. This is
-	  unneeded because we can check the macro directly in source code,
-	  just as we already do for OPENSSL_NO_* macros.
-
-	* ext/openssl/ossl.c: Replace occurrences of HAVE_OPENSSL_FIPS with
-	  OPENSSL_FIPS.
-
-Wed May 25 17:13:35 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* class.c (rb_scan_args): merge code for n_trail.
-
-Wed May 25 17:11:34 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/ruby.h (rb_scan_args_validate): move failed
-	  condition to the terminal.  [ruby-core:75714] [Bug #12426]
-
-Wed May 25 13:13:37 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* regcomp.c: remove condition for debug output because prelude
-	  doesn't use regexp now.
-
-Wed May 25 13:10:30 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* regcomp.c (compile_length_tree): return error code immediately
-	  if compile_length_tree raised error [Bug #12418]
-
-Wed May 25 08:01:39 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Fix flag error for switch from titlecase to lowercase.
-
-	* test/ruby/enc/test_case_mapping.rb: Tests for above error.
-
-Wed May 25 01:13:55 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_pkey_ec.c (ec_key_new_from_group): Create a new
-	  EC_KEY on given EC group. Extracted from ossl_ec_key_initialize().
-	  (ossl_ec_key_s_generate): Added. Create a new EC instance and
-	  generate a random private and public key.
-	  (ossl_ec_key_initialize): Use ec_key_new_from_group().
-	  (Init_ossl_ec): Define the new method EC.generate. This change is
-	  for consistency with other PKey types.  [ruby-core:45541] [Bug #6567]
-
-	* test/openssl/test_pkey_ec.rb: Test that EC.generate works.
-
-Wed May 25 00:37:16 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_pkey_ec.c (ossl_ec_key_generate_key): Fix up RDoc.
-	  (Init_ossl_ec): Rename EC#generate_key to EC#generate_key!. Make the
-	  old name an alias of #generate_key!. This change is for consistency
-	  with other PKey types.  [ruby-core:45541] [Bug #6567]
-
-	* test/openssl/test_pkey_ec.rb: Use EC#generate_key! instead of
-	  EC#generate_key.
-
-Wed May 25 00:23:05 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/ruby.h (rb_scan_args_set): check the arity after
-	  adjusting argc for an option hash, for optimization in simpler
-	  cases.
-
-Wed May 25 00:21:52 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* configure.in (XCFLAGS): merge flags only for ruby itself from
-	  ruby_cflags.
-
-Tue May 24 22:04:15 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_cipher.c (ossl_cipher_set_key, ossl_cipher_set_iv):
-	  Reject too long values as well as too short ones. Currently they
-	  just truncate the input but this would hide bugs and lead to
-	  unexpected encryption/decryption results.
-
-	* test/openssl/test_cipher.rb: Test that Cipher#key= and #iv= reject
-	  Strings with invalid length.
-
-Tue May 24 21:32:21 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_x509ext.c (ossl_x509ext_set_value): Use
-	  ASN1_OCTET_STRING_set() instead of M_ASN1_OCTET_STRING_set(). Macros
-	  prefixed by "M_" are discouraged to be used from outside OpenSSL
-	  library[1].
-	  (ossl_x509ext_get_value): Likewise, use ASN1_STRING_print() instead
-	  of M_ASN1_OCTET_STRING_print().
-	  [1] https://git.openssl.org/gitweb/?p=openssl.git;a=blob;f=CHANGES;h=bf61913d7b01212b4d8b2f3c13d71d645914f67c;hb=b6079a7835f61daa9fb2cbf9addfa86049523933#l878
-
-	* ext/openssl/ossl.h: Include openssl/asn1.h instead of
-	  openssl/asn1_mac.h. It just includes openssl/asn1.h and defines some
-	  additional "M_" macros.
-
-Tue May 24 18:52:11 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/ruby.h (rb_scan_args_verify): verify the format to
-	  scan if no invalid chars and variable argument length matching,
-	  at the compile time if possible.
-
-Tue May 24 17:18:46 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/defines.h (ERRORFUNC, WARNINGFUNC): add fallback
-	  definitions.
-
-Tue May 24 16:37:43 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* configure.in (ruby_cflags): separate from optflags [Bug #12409]
-	  -fexcess-precision=standard and -fp-model precise are set to this now.
-
-	* configure.in (cflags): use ruby_cflags.
-
-Tue May 24 16:20:53 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* configure.in (ERRORFUNC, WARNINGFUNC): __error__ and __warning__
-	  attributes take a parenthesized string literal.
-
-Tue May 24 12:35:56 2016  URABE Shyouhei  <shyouhei@ruby-lang.org>
-
-	* common.mk: sort lines, and add missing dependencies suggested
-	  by tool/update-deps
-
-Mon May 23 21:33:36 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/missing.h (isfinite): move from numeric.c.
-
-Mon May 23 21:09:06 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl.c (Init_openssl): Avoid reference to unset global
-	  variable. ossl_raise() may be called before dOSSL is set. Since
-	  global variables default to 0 and the default value of dOSSL set in
-	  Init_openssl() is also Qfalse, there is no real issue but confusing.
-	  Patch by Bertram Scharpf <software@bertram-scharpf.de>
-	  [ruby-core:58264] [Bug #9101]
-
-Mon May 23 20:32:16 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_asn1.c, ext/openssl/ossl_bn.c,
-	  ext/openssl/ossl_cipher.c, ext/openssl/ossl_digest.c
-	  ext/openssl/ossl_engine.c, ext/openssl/ossl_ns_spki.c
-	  ext/openssl/ossl_pkcs12.c, ext/openssl/ossl_pkcs7.c
-	  ext/openssl/ossl_pkey.c, ext/openssl/ossl_pkey_ec.c
-	  ext/openssl/ossl_rand.c, ext/openssl/ossl_ssl.c
-	  ext/openssl/ossl_x509attr.c, ext/openssl/ossl_x509cert.c
-	  ext/openssl/ossl_x509ext.c, ext/openssl/ossl_x509store.c: Use
-	  StringValueCStr() where NUL-terminated string is expected.
-
-Mon May 23 20:20:12 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* ext/bigdecimal/bigdecimal.c (isfinite): get rid of a warning on
-	  cygwin. [Bug #12417][ruby-core:75691]
-
-Mon May 23 19:41:27 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_rand.c (ossl_rand_egd, ossl_rand_egd_bytes):
-	  RAND_egd{_bytes,}() return -1 on failure, not 0.
-	  Patch by cremno phobia <cremno@mail.ru>
-	  [ruby-core:63795] [Bug #10053]
-	  (ossl_pseudo_bytes): Similar, RAND_pseudo_bytes() may return 0 or
-	  -1 on failure.
-
-Mon May 23 15:52:07 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* ext/bigdecimal/bigdecimal.c (isfinite): isfinite does not always
-	  exist.  fixed build error on Windows introduced at r55123.
-
-Mon May 23 13:19:41 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/ruby.h (rb_scan_args0): make compile error if the
-	  format is wrong or does not match with the variable argument
-	  length if possible.
-
-Mon May 23 12:47:09 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/ruby.h (rb_scan_args0): raise fatal error if
-	  variable argument length does not match, it is a bug in the code
-	  which uses rb_scan_args, not a runtime error.
-
-Mon May 23 12:30:29 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/bigdecimal/bigdecimal.c (GetVpValueWithPrec): consider
-	  non-finite float values not to raise FloatDomainError.
-	  [ruby-core:75682] [Bug #12414]
-
-Mon May 23 12:21:18 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* array.c (rb_ary_fill): suppress warnings: 'item' may be used
-	  uninitialized in this function
-
-Mon May 23 07:41:49 2016  Eric Wong  <e@80x24.org>
-
-	* dir.c (dir_close): update RDoc for 2.3 #close change
-	  [ruby-core:75679] [Bug #12413]
-
-Sun May 22 20:01:21 2016  Masatoshi SEKI  <m_seki@mva.biglobe.ne.jp>
-
-	* lib/drb/timeridconv.rb: use finalizer trick instead of thread.
-
-	* test/drb/ut_timerholder.rb: ditto.
-
-Sun May 22 17:25:18 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_options.rb: adjust test class name
-	  to match file name
-
-Sun May 22 17:24:07 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* rename test/ruby/enc/test_casing_options.rb to test_case_options.rb
-	  for consistency
-
-Sun May 22 17:06:55 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* transcode.c (enc_arg, str_transcode_enc_args, econv_args):
-	  remove volatile, and add GC guards in callers.
-	  [ruby-core:75664] [Bug #12411]
-
-Sun May 22 16:27:00 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/-test-/integer/core_ext.c: move testutil/integer.c.
-
-	* test/lib/-test-/integer.rb: extract implementation details from
-	  test/unit/assertions.rb.  [Bug #12408]
-
-Sun May 22 14:57:43 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* include/ruby/oniguruma.h: Extend OnigEncodingTypeDefine to define a
-	  new encoding primitive 'case_map' for case mapping
-
-	* enc/utf-8.c, utf_16be/le.c, utf_32be/le.c:
-	  add onigenc_unicode_case_map as case_map primitive
-
-	* enc/ascii.c, big5.c, cp949.c, emacs_mule.c, euc_jp/kr/tw.c, gb18030.c,
-	  gbk.c, iso_8859_1/2/3/4/5/6/7/8/9/10/11/13/14/15/16.c, koi8_r/u.c,
-	  shift_jis.c, us_ascii.c, windows_1250/1251/1252.c:
-	  add onigenc_not_support_case_map as case_map primitive
-
-Sun May 22 14:45:45 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* regenc.h/c: Define new function onigenc_not_support_case_map
-
-Sun May 22 12:14:06 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* include/ruby/ruby.h (rb_scan_args): use original rb_scan_args
-	  when fmt is dynamic.
-
-Sun May 22 11:41:12 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* class.c (rb_scan_args): moved to bottom of the file to make the
-	  effect of `#undef rb_scan_args` the minimum.
-
-	* include/ruby/ruby.h (rb_scan_args): overwrite only if GCC and
-	  optimized. Visual C++ 14 or later can compile it but make it
-	  conservative.
-
-Sat May 21 22:45:50 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* include/ruby/ruby.h (rb_scan_args): don't use ALWAYS_INLINE with
-	  `inline`.  if gcc needs this duplication, do in ALWAYS_INLINE macro.
-
-Sat May 21 21:11:56 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* include/ruby/ruby.h (rb_scan_args): use __VA_ARGS__ instead of
-	  va_arg to allow compilers optimize more aggressive.
-	  https://gustedt.wordpress.com/2011/07/10/avoid-writing-va_arg-functions/
-	  rb_scan_args is now expected to be statically resolved.
-
-Sun May 22 02:41:52 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* ext/zlib/zlib.c: remove hacky macro introduced at r30437.
-
-	* ext/zlib/zlib.c (gzfile_make_header): cast as long (instead of int).
-
-	* ext/zlib/zlib.c (gzfile_make_footer): ditto.
-
-Sat May 21 21:07:18 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* configure.in (ALWAYS_INLINE): force compilers the function inlined.
-
-Sat May 21 16:16:03 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_ssl.c (ossl_ssl_stop): Don't free the SSL struct
-	  here. Since some methods such as SSLSocket#connect releases GVL,
-	  there is a chance of use after free if we free the SSL from another
-	  thread. SSLSocket#stop was documented as "prepares it for another
-	  connection" so this is a slightly incompatible change. However when
-	  this sentence was added (r30090, Add toplevel documentation for
-	  OpenSSL, 2010-12-06), it didn't actually. The current behavior is
-	  from r40304 (Correct shutdown behavior w.r.t GC., 2013-04-15).
-	  [ruby-core:74978] [Bug #12292]
-
-	* ext/openssl/lib/openssl/ssl.rb (sysclose): Update doc.
-
-	* test/openssl/test_ssl.rb: Test this.
-
-Sat May 21 14:41:14 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl.c: [DOC] Fix SSL client example. The variable name
-	  was wrong. Patch by Andreas Tiefenthaler <at@an-ti.eu> (@pxlpnk).
-	  [GH ruby/openssl#32]
-
-Sat May 21 14:25:38 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_pkey_ec.c: rename PKey::EC#private_key? and
-	  #public_key? to #private? and #public? for consistency with other
-	  PKey types. Old names remain as alias.  [ruby-core:45541] [Bug #6567]
-
-	* test/openssl/test_pkey_ec.rb (test_check_key): check private? and
-	  public? works correctly.
-
-Sat May 21 12:40:36 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/lib/openssl/buffering.rb (read_nonblock, readpartial):
-	  Remove impossible EOFError raise. Patch by Zach Anker
-	  <zanker@squareup.com>.  [GH ruby/openssl#23]
-
-Sat May 21 11:18:42 2016  Evgeni Golov  <evgeni@golov.de>
-
-	* lib/ipaddr.rb: [DOC] fix documentation of IN6MASK to mention
-	  IPv6.  [Fix GH-1349]
-
-Sat May 21 11:12:53 2016  Dan Martinez  <dfm@razorwind.org>
-
-	* io.c (Init_IO): [DOC] define dummy ARGF instead of ARGF.class to
-	  re-enable the generation of ARGF documentation.  [Fix GH-1358]
-
-Sat May 21 11:07:29 2016  0x01f7  <souk.0x01f7@gmail.com>
-
-	* doc/syntax/methods.rdoc (Method Names): add proper closing tag.
-	  [Fix GH-1356]
-
-Sat May 21 09:26:28 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* configure.in (RUBY_CHECK_SETJMP): fix missing macro definition
-	  for the configured result.  fix up r55021.
-
-Sat May 21 00:36:32 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* process.c (rb_execarg_commandline): build command line string
-	  from argument vector in rb_execarg.
-	  [ruby-core:75611] [Bug #12398]
-
-Fri May 20 23:25:42 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl.c (ossl_pem_passwd_value): Added. Convert the
-	  argument to String with StringValue() and validate the length is in
-	  4..PEM_BUFSIZE. PEM_BUFSIZE is a macro defined in OpenSSL headers.
-	  (ossl_pem_passwd_cb): When reading/writing encrypted PEM format, we
-	  used to pass the password to PEM_def_callback() directly but it was
-	  problematic. It is not NUL character safe. And surprisingly, it
-	  silently truncates the password to 1024 bytes.  [GH ruby/openssl#51]
-
-	* ext/openssl/ossl.h: Add function prototype declaration of newly
-	  added ossl_pem_passwd_value().
-
-	* ext/openssl/ossl_pkey.c (ossl_pkey_new_from_data): Use
-	  ossl_pem_passwd_value() to validate the password String.
-
-	* ext/openssl/ossl_pkey_dsa.c (ossl_dsa_initialize, ossl_dsa_export):
-	  ditto.
-
-	* ext/openssl/ossl_pkey_ec.c (ossl_ec_key_initialize,
-	  ossl_ec_key_to_string): ditto.
-
-	* ext/openssl/ossl_pkey_rsa.c (ossl_rsa_initialize, ossl_rsa_export):
-	  ditto.
-
-	* test/openssl/test_pkey_{dsa,ec,rsa}.rb: test this.
-
-Fri May 20 23:45:53 2016  Naohisa Goto  <ngotogenome@gmail.com>
-
-	* id_table.c (list_id_table_init): When unaligned word access is
-	  prohibited and sizeof(VALUE) is 8 (64-bit machines),
-	  capa should always be even number for 8-byte word alignment
-	  of the values of a table. This code assumes that sizeof(ID) is 4,
-	  sizeof(VALUE) is 8, and xmalloc() returns 8-byte aligned memory.
-	  This fixes bus error on 64-bit SPARC Solaris 10.
-	  [Bug #12406][ruby-dev:49631]
-
-Fri May 20 22:30:09 2016  Naohisa Goto  <ngotogenome@gmail.com>
-
-	* symbol.h (rb_id2sym): Use HAVE_BUILTIN___BUILTIN_CONSTANT_P
-
-Fri May 20 22:19:00 2016  Kazuhiro NISHIYAMA  <zn@mbf.nifty.com>
-
-	* ext/date/date_core.c: [DOC] fix typos.
-	  [fix GH-1360] patched by @soundasleep
-
-Fri May 20 21:26:58 2016  Naohisa Goto  <ngotogenome@gmail.com>
-
-	* include/ruby/defines.h (RB_GNUC_EXTENSION, RB_GNUC_EXTENSION_BLOCK):
-	  macros for skipping __extension__ on non-GCC compilers.
-	* eval_error.c (warn_print): use RB_GNUC_EXTENSION_BLOCK instead of
-	  __extension__ because __extension__ is a GNU extension.
-	  Fix compile error on Solaris 10 with Oracle Solaris Studio 12.x.
-	  [Bug #12397] [ruby-dev:49629].
-	* internal.h (rb_fstring_cstr, rb_fstring_enc_cstr): ditto
-	* include/ruby/encoding.h (rb_enc_str_new, rb_enc_str_new_cstr): ditto
-	* include/ruby/intern.h (rb_str_new, rb_str_new_cstr,
-	  rb_usascii_str_new, rb_utf8_str_new, rb_tainted_str_new_cstr,
-	  rb_usascii_str_new_cstr, rb_utf8_str_new_cstr,
-	  rb_external_str_new_cstr, rb_locale_str_new_cstr,
-	  rb_str_buf_new_cstr, rb_str_cat_cstr, rb_exc_new_cstr): ditto
-
-Fri May 20 21:17:13 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/win32ole/win32ole.c (fole_missing): make substring or dup to
-	  share the content if possible.
-
-Fri May 20 19:48:48 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* internal.h (NEW_PARTIAL_MEMO_FOR): shrink buffer array not to
-	  mark non-VALUE fields.  fix check_rvalue_consistency abort with
-	  RGENGC_CHECK_MODE=2.
-
-	* internal.h (NEW_CMP_OPT_MEMO): exclude struct cmp_opt_data from
-	  the valid array range.
-
-	* enum.c (slicewhen_i): exclude inverted too.
-
-Thu May 19 21:21:57 2016  Kazuhiro NISHIYAMA  <zn@mbf.nifty.com>
-
-	* re.c (rb_reg_match_m_p): [DOC] fix return value in rdoc.
-
-	* test/ruby/test_regexp.rb (TestRegexp#test_match_p): add some
-	  tests from document.
-
-Thu May 19 13:22:44 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl.c (Init_openssl): register an ex_data index for
-	  X509_STORE and X509_STORE_CTX respectively. Since they don't share
-	  the ex_data index registry, we can't use the same index.
-	  (ossl_verify_cb): use the the correct index.
-
-	* ext/openssl/ossl_ssl.c (ossl_ssl_verify_callback): ditto.
-
-	* ext/openssl/ossl_x509store.c (ossl_x509store_set_vfy_cb): ditto.
-	  (ossl_x509stctx_verify): ditto.
-
-	* ext/openssl/ossl.h (void ossl_clear_error): add extern declarations
-	  of ossl_store_{ctx_,}ex_verify_cb_idx.
-
-	* ext/openssl/openssl_missing.c: remove X509_STORE_set_ex_data and
-	  X509_STORE_get_ex_data.
-
-	* ext/openssl/openssl_missing.h: implement X509_STORE_get_ex_data,
-	  X509_STORE_set_ex_data and X509_STORE_get_ex_new_index as macros.
-
-Thu May 19 13:11:35 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_x509attr.c (ossl_x509attr_set_value): check that the
-	  argument is an OpenSSL::ASN1::Data before converting to ASN1_TYPE.
-	  This fixes SEGV on OpenSSL::X509::Attribute#value=(non-asn1-value).
-
-	* test/openssl/test_x509attr.rb: add tests for OpenSSL::X509::Attribute.
-
-Thu May 19 12:10:10 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* re.c (rb_reg_match_m_p): fix match against empty string.
-	  rb_str_offset returns the end when the position exceeds the
-	  length.  fix the range parameter of onig_search.
-	  [ruby-core:75604] [Bug #12394]
-
-Thu May 19 11:37:36 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* re.c (rb_reg_match_m_p): should return false if no match, as the
-	  document says.  [Feature #8110]
-
-Thu May 19 00:17:01 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* re.c (reg_names_iter): specify capacify
-
-Wed May 18 21:29:59 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* thread.c (recursive_list_access): a object id may be a Bignum.  so,
-	  the list must be a objhash, instead of a identhash.
-	  this fixes many test errors on mswin64 CI.
-
-Wed May 18 19:33:54 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* re.c (rb_reg_match_m_p): Introduce Regexp#match?, which returns
-	  bool and doesn't save backref.
-
-Wed May 18 16:52:03 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_pkcs12.c (ossl_pkcs12_initialize): pop errors
-	  leaked by PKCS12_parse(). This is a bug in OpenSSL, which exists
-	  in the versions before the version 1.0.0t, 1.0.1p, 1.0.2d.
-
-Wed May 18 16:04:54 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* tool/downloader.rb (Downloader::RubyGems.download): verify gems
-	  only if RubyGems is 2.4 or later.  old RubyGems fails to verify
-	  almost all of bundled gems.
-
-Wed May 18 14:52:38 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* string.c (rb_str_modify_expand): check integer overflow.
-	  [ruby-core:75592] [Bug #12390]
-
-Wed May 18 13:11:44 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* re.c (match_ary_subseq): get subseq of match array without creating
-	  temporary array.
-
-	* re.c (match_ary_aref): get element(s) of match array without creating
-	  temporary array.
-
-	* re.c (match_aref): Use match_ary_subseq with handling irregulars.
-
-	* re.c (match_values_at): Use match_ary_aref.
-
-Wed May 18 13:03:07 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_x509cert.c (ossl_x509_verify): X509_verify()
-	  family may put errors on 0 return (0 means verification failure).
-	  Clear OpenSSL error queue before return to Ruby. Since the queue is
-	  thread global, remaining errors in the queue can cause an unexpected
-	  error in the next OpenSSL operation.  [ruby-core:48284] [Bug #7215]
-
-	* ext/openssl/ossl_x509crl.c (ossl_x509crl_verify): ditto.
-
-	* ext/openssl/ossl_x509req.c (ossl_x509req_verify): ditto.
-
-	* ext/openssl/ossl_x509store.c (ossl_x509stctx_verify): ditto.
-
-	* ext/openssl/ossl_pkey_dh.c (dh_generate): clear the OpenSSL error
-	  queue before re-raising exception.
-
-	* ext/openssl/ossl_pkey_dsa.c (dsa_generate): ditto.
-
-	* ext/openssl/ossl_pkey_rsa.c (rsa_generate): ditto.
-
-	* ext/openssl/ossl_ssl.c (ossl_start_ssl): ditto.
-
-	* test/openssl: check that OpenSSL.errors is empty every time after
-	  running a test case.
-
-Wed May 18 12:07:42 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl.c (ossl_clear_error): Extracted from
-	  ossl_make_error(). This prints errors in the OpenSSL error queue if
-	  OpenSSL.debug is true, and clears the queue.
-	  (ossl_make_error): use ossl_clear_error().
-
-	* ext/openssl/ossl.h: add prototype declaration of ossl_make_error().
-	  (OSSL_BIO_reset) use ossl_clear_error() to clear the queue. Clearing
-	  silently makes debugging difficult.
-
-	* ext/openssl/ossl_engine.c (ossl_engine_s_by_id): ditto.
-
-	* ext/openssl/ossl_ns_spki.c (ossl_spki_initialize): ditto.
-
-	* ext/openssl/ossl_pkcs7.c (ossl_pkcs7_verify): ditto.
-
-	* ext/openssl/ossl_pkey_dsa.c (ossl_dsa_initialize): ditto.
-
-	* ext/openssl/ossl_pkey_ec.c (ossl_ec_key_initialize): ditto.
-	  (ossl_ec_group_initialize): ditto.
-
-	* ext/openssl/ossl_ssl.c (ossl_ssl_shutdown): ditto.
-
-Wed May 18 11:53:49 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_pkey_ec.c (ossl_ec_point_mul): Validate the
-	  arguments before passing to EC_POINT(s)_mul(). Add description of this
-	  method.  [ruby-core:65152] [Bug #10268]
-
-	* test/openssl/test_pkey_ec.rb (test_ec_point_mul): Test that
-	  OpenSSL::PKey::EC::Point#mul works.
-
-Wed May 18 11:19:59 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/ossl_bn.c (try_convert_to_bnptr): Extracted from
-	  GetBNPtr(). This doesn't raise exception but returns NULL on error.
-	  (GetBNPtr): Raise TypeError if conversion fails.
-	  (ossl_bn_eq): Implement BN#==.
-	  (ossl_bn_eql): #eql? should not raise TypeError even if the argument
-	  is not compatible with BN.
-	  (ossl_bn_hash): Implement BN#hash.
-
-	* ext/openssl/ossl_bn.c (Init_ossl_bn): Define #== and #hash.
-
-	* test/openssl/test_bn.rb: Test BN#eql?, #== and #hash
-
-Wed May 18 10:17:41 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/ruby.h (RB_INTEGER_TYPE_P): new macro and
-	  underlying inline function to check if the object is an
-	  Integer (Fixnum or Bignum).
-
-Wed May 18 09:52:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* enum.c (enum_sum, hash_sum, hash_sum_i, enum_sum_i, sum_iter):
-	  Optimize for hashes when each method isn't redefined.
-
-Wed May 18 09:14:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* enum.c (enum_sum, int_range_sum): Extract int_range_sum from
-	  enum_sum.
-
-Wed May 18 03:16:06 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* re.c (match_values_at): fix regression at r55036.
-	  MatchData#values_at accepts Range.
-
-Wed May 18 02:02:58 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* re.c (match_aref): remove useless condition and call rb_fix2int.
-	  rb_reg_nth_match handles negative index.
-
-Wed May 18 01:57:43 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* re.c (match_values_at): MatchData#values_at supports named captures
-	  [Feature #9179]
-
-	* re.c (namev_to_backref_number): separated.
-
-Wed May 18 00:05:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* enum.c (enum_sum): Optimize for a range from int to int.
-
-	* test/ruby/test_enum.rb (test_range_sum): Move from test_range.rb,
-	  and add assertions for some conditions.
-
-	* test/ruby/test_enum.rb (test_hash_sum): Move from test_hash.rb.
-
-	* test/ruby/test_hash.rb, test/ruby/test_range.rb: Remove test_sum.
-
-Tue May 17 23:08:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* enum.c (enum_sum): [DOC] Write documentation.
-
-Tue May 17 22:53:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* enum.c (enum_sum): Implement Enumerable#sum.
-
-	* test/ruby/test_enum.rb (test_sum): Test sum for Enumerable.
-
-	* test/ruby/test_hash.rb (test_sum): Test sum for Hash.
-
-	* test/ruby/test_range.rb (test_sum): Test sum for Range.
-
-Tue May 17 22:11:41 2016  Tanaka Akira  <akr@fsij.org>
-
-	* object.c, numeric.c, enum.c, ext/-test-/bignum/mul.c,
-	  lib/rexml/quickpath.rb, lib/rexml/text.rb, lib/rexml/xpath_parser.rb,
-	  lib/rubygems/specification.rb, lib/uri/generic.rb,
-	  bootstraptest/test_eval.rb, basictest/test.rb,
-	  test/-ext-/bignum/test_big2str.rb, test/-ext-/bignum/test_div.rb,
-	  test/-ext-/bignum/test_mul.rb, test/-ext-/bignum/test_str2big.rb,
-	  test/csv/test_data_converters.rb, test/date/test_date.rb,
-	  test/json/test_json_generate.rb, test/minitest/test_minitest_mock.rb,
-	  test/openssl/test_cipher.rb, test/rexml/test_jaxen.rb,
-	  test/ruby/test_array.rb, test/ruby/test_basicinstructions.rb,
-	  test/ruby/test_bignum.rb, test/ruby/test_case.rb,
-	  test/ruby/test_class.rb, test/ruby/test_complex.rb,
-	  test/ruby/test_enum.rb, test/ruby/test_eval.rb,
-	  test/ruby/test_iseq.rb, test/ruby/test_literal.rb,
-	  test/ruby/test_math.rb, test/ruby/test_module.rb,
-	  test/ruby/test_numeric.rb, test/ruby/test_range.rb,
-	  test/ruby/test_rational.rb, test/ruby/test_refinement.rb,
-	  test/ruby/test_rubyvm.rb, test/ruby/test_struct.rb,
-	  test/ruby/test_variable.rb, test/rubygems/test_gem_specification.rb,
-	  test/thread/test_queue.rb: Use Integer instead of Fixnum and Bignum.
-
-Tue May 17 15:26:10 2016  Tanaka Akira  <akr@fsij.org>
-
-	* [Feature #12005] Unify Fixnum and Bignum into Integer
-
-	* include/ruby/ruby.h (rb_class_of): Return rb_cInteger for fixnums.
-
-	* insns.def (INTEGER_REDEFINED_OP_FLAG): Unified from
-	  FIXNUM_REDEFINED_OP_FLAG and BIGNUM_REDEFINED_OP_FLAG.
-
-	* vm_core.h: Ditto.
-
-	* vm_insnhelper.c (opt_eq_func): Use INTEGER_REDEFINED_OP_FLAG instead
-	  of FIXNUM_REDEFINED_OP_FLAG.
-
-	* vm.c (vm_redefinition_check_flag): Use rb_cInteger instead of
-	  rb_cFixnum and rb_cBignum.
-	  (C): Use Integer instead of Fixnum and Bignum.
-
-	* numeric.c (fix_succ): Removed.
-	  (Init_Numeric): Define Fixnum as Integer.
-
-	* bignum.c (bignew): Use rb_cInteger instead of rb_cBignum.
-	  (rb_int_coerce): replaced from rb_big_coerce and return fixnums
-	  as-is.
-	  (Init_Bignum): Define Bignum as Integer.
-	  Don't define ===.
-
-	* error.c (builtin_class_name): Return "Integer" for fixnums.
-
-	* sprintf.c (ruby__sfvextra): Use rb_cInteger instead of rb_cFixnum.
-
-	* ext/-test-/testutil: New directory to test.
-	  Currently it provides utilities for fixnum and bignum.
-
-	* ext/json/generator/generator.c: Define mInteger_to_json.
-
-	* lib/mathn.rb (Fixnum#/): Redefinition removed.
-
-Tue May 17 11:58:58 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* configure.in (RUBY_CHECK_BUILTIN_SETJMP): declare t as NORETURN
-	  to suppress warnings by -Wsuggest-attribute=noreturn.
-	  [ruby-core:75510] [Bug #12383]
-
-Tue May 17 10:40:18 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* configure.in (RUBY_CHECK_SETJMP): needs the header and proper
-	  arguments for builtin setjmp functions.
-
-Mon May 16 20:00:30 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.h: Additional uses of ONIG_CASE_MAPPING compilation switch
-
-Mon May 16 19:46:33 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* include/ruby/oniguruma.h: Introducing ONIG_CASE_MAPPING compilation
-	  switch
-
-	* include/ruby/oniguruma.h, enc/unicode.h: Using ONIG_CASE_MAPPING
-	  compilation switch
-
-Mon May 16 19:29:31 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* gems/bundled_gems: Update xmlrpc-0.1.1. xmlrpc-0.1.0 didn't allow
-	  to install on 2.4.0dev.
-
-Mon May 16 13:28:59 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* configure.in (FUNC_STDCALL, FUNC_CDECL, FUNC_FASTCALL): set
-	  macro names explicitly to the old names, which are accidentally
-	  changed at r54985, for backward compatibilities.
-	  fiddle also depends on these names to fallback to ANSI names.
-	  [ruby-core:75494] [Bug #12377]
-
-Mon May 16 11:39:02 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/xmlrpc.rb, lib/xmlrpc/*, test/xmlrpc: XMLRPC is bundled gem
-	  on Ruby 2.4. It is extracted to https://github.com/ruby/xmlrpc
-	  [Feature #12160][ruby-core:74239]
-	* gems/bundled_gems: ditto.
-
-Mon May 16 06:06:21 2016  Eric Wong  <e@80x24.org>
-
-	* proc.c: fix RDoc of Proc#===/call/yield/[]
-	  [Bug #12332]
-
-Sun May 15 20:55:31 2016  Masatoshi SEKI  <m_seki@mva.biglobe.ne.jp>
-
-	* lib/drb/timeridconv.rb: don't use keeper thread. [Bug #12342]
-
-	* test/drb/ut_timerholder.rb: ditto.
-
-Sun May 15 16:15:25 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* array.c (rb_ary_entry): extract rb_ary_elt to organize if-conditions
-	  and check whether is embedded at once.
-
-Sun May 15 10:57:26 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* vm_insnhelper.c (vm_get_ev_const): warn deprecated constant even
-	  in the class context.  [ruby-core:75505] [Bug #12382]
-
-Sun May 15 03:13:01 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* iseq.h (struct iseq_compile_data): use struct rb_id_table
-	  instead of st_table.
-
-	* iseq.c (prepare_iseq_build): don't allocate ivar_cache_table
-	  until it has at least one element.
-
-	* iseq.c (compile_data_free): free ivar_cache_table only if it
-	  is allocated.
-
-	* compile.c (get_ivar_ic_value): allocate if the table is not
-	  allocated yet.
-
-Sat May 14 09:04:34 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/mkmf.rb (pkg_config): use xsystem consistently to set up
-	  library path environment variable as well as latter pkg-config
-	  calls.  [ruby-dev:49619] [Bug #12379]
-
-Sat May 14 00:16:54 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* random.c (make_seed_value): append leading-zero-guard and get
-	  rid of making a local copy of the seed.
-
-Fri May 13 08:46:42 2016  cremno  <cremno@mail.ru>
-
-	* NEWS: drop FreeBSD < 4 support.  [Fix GH-1339]
-	  The most recent version affected by this is 3.5 and was released
-	  in 2000.
-	  https://www.freebsd.org/releases/3.5R/announce.html
-	  https://en.wikipedia.org/wiki/History_of_FreeBSD#Version_history
-
-Fri May 13 03:12:09 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* include/ruby/defines.h (GCC_VERSION_SINCE): moved from internal.h.
-
-Fri May 13 03:11:20 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* configure.in (__builtin_constant_p): check.
-
-	* internal.h: Use HAVE_BUILTIN___BUILTIN_CONSTANT_P
-
-Fri May 13 03:10:39 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* configure.in: use alternative keyword
-	  to avoid macros conflicts with them.
-
-Thu May 12 01:54:08 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/mkmf.rb (try_func): get rid of conflict of declarations of
-	  main().  checking local symbol reference does not make sense.
-
-Thu May 12 00:18:19 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* win32/Makefile.sub (HAVE_QSORT_S): use qsort_s only for Visual Studio
-	  2012 or later, because VS2010 seems to causes a SEGV in
-	  test/ruby/test_enum.rb.
-
-Wed May 11 23:59:47 2016  Masaya Tarui  <tarui@ruby-lang.org>
-
-	* vm_insnhelper.c (vm_getivar): describe fast-path explicit
-	  (compiler friendly). [Bug #12274].
-
-Wed May 11 21:30:07 2016  Masaya Tarui  <tarui@ruby-lang.org>
-
-	* compile.c (iseq_compile_each): share InlineCache during same
-	  instance variable accesses. Reducing memory consumption,
-	  rising cache hit rate and rising branch prediction hit rate
-	  are expected. A part of [Bug #12274].
-
-	* iseq.h (struct iseq_compile_data): introduce instance
-	  variable IC table for sharing.
-
-	* iseq.c (prepare_iseq_build, compile_data_free):
-	  construct/destruct above table.
-
-Wed May 11 17:18:53 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* util.c (ruby_qsort): use qsort_s if available, for Microsoft
-	  Visual Studio 2005 (msvcr80.dll) and mingw.
-
-Wed May 11 10:33:26 2016  Marcus Stollsteimer  <sto.mar@web.de>
-
-	* COPYING: Remove trailing-whitespaces.
-	  [ci skip][fix GH-1348]
-
-Tue May 10 21:05:45 2016  Benoit Daloze  <eregontp@gmail.com>
-
-	* insns.def (defineclass): Also raise an error when redeclaring the
-	  superclass of a class as Object and it has another superclass.
-	  [Bug #12367] [ruby-core:75446]
-
-	* test/ruby/test_class.rb: test for above.
-
-Tue May 10 14:57:09 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* random.c (obj_random_bytes): base on bytes method instead of
-	  rand method, not to call toplevel rand method.
-
-Tue May 10 13:07:28 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* configure.in (-fexcess-precision=standard): before r54895 -std=c99
-	  is specified and it implied -fexcess-precision=standard.
-	  Now with -std=gnu99, it should be explicitly specified.
-	  https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html
-
-Mon May  9 10:51:59 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* thread.c (rb_thread_atfork_internal): move th to an argument.
-
-	* thread.c (rb_thread_atfork): do not repeat GET_THREAD().
-
-Mon May  9 10:46:36 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* thread.c (rb_thread_atfork, rb_thread_atfork_before_exec): do
-	  nothing unless working fork is available.
-
-	* thread_sync.c (rb_mutex_abandon_all): define only if working
-	  fork is available.
-
-	* thread_sync.c (rb_mutex_abandon_keeping_mutexes): ditto.
-
-	* thread_sync.c (rb_mutex_abandon_locking_mutex): ditto.
-
-	* thread_win32.c (gvl_init): never used.
-
-Mon May  9 07:18:06 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* include/ruby/{defines,ruby}.h: need to define function attributes
-	  alternatives in defines.h instead of ruby.h, because they are used
-	  in oniguruma.h and the header used without including ruby.h at
-	  encoding library sources.
-
-Mon May  9 06:30:12 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* include/ruby/ruby.h (CONSTFUNC, PUREFUNC): fixed build errors on
-	  non-gcc build environments introduced at r54952.
-
-Mon May  9 02:51:51 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* gc.c (rb_gc_unprotect_logging): throw rb_memerror when it cannot
-	  allocate memory. This is pointed out by Facebook's Infer.
-
-	* gc.c (gc_prof_setup_new_record): ditto.
-
-	* regparse.c (parse_regexp): ditto.
-
-	* util.c (MALLOC): use xmalloc and xfree like above.
-
-Mon May  9 02:39:16 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* configure.in: check function attribute const and pure,
-	  and define CONSTFUNC and PUREFUNC if available.
-	  Note that I don't add those options as default because
-	  it still shows many false-positive (it seems not to consider
-	  longjmp).
-
-	* vm_eval.c (stack_check): get rb_thread_t* as an argument
-	  to avoid duplicate call of GET_THREAD().
-
-Sun May  8 21:01:14 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* ext/openssl/extconf.rb: assume it doesn't have SSLv2 related
-	  functions when OPENSSL_NO_SSL2 is defined.
-	  Usually openssl's header and the library (libssl) have the same
-	  set of functions, but on some environment the library has functions
-	  whose headers doesn't declare. (openssl/opensslconf.h and libssl.so
-	  aren't be synchronized)
-	  To detect such case explicitly check feature macro and remove
-	  related functions.
-
-Sun May  8 18:51:33 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* file.c (rb_home_dir_of): return the default home path if the
-	  user name is the current user name, on platforms where struct
-	  pwd is not supported.  a temporary measure against
-	  [Bug #12226].
-
-Sun May  8 08:51:38 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* configure.in: add -Wsuggest-attribute=format and suppress warnings.
-
-Sun May  8 08:31:03 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* configure.in: add -Wsuggest-attribute=noreturn and suppress warnings.
-
-Sun May  8 08:19:16 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* configure.in: add -Werror=implicit-int to avoid missing type of
-	  function declaration.
-
-Sat May  7 22:22:37 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/webrick/ssl.rb: Accept string value for SSLCertName. It is used
-	  to invoke ssl server with command line.
-	  [fix GH-1329] Patch by @kerlin
-	* test/webrick/test_ssl_server.rb: Added test for GH-1329
-
-Sat May  7 21:55:12 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* test/webrick/test_ssl_server.rb: Added basic test for `webrick/ssl`
-
-Sat May  7 16:22:13 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* random.c (int_pair_to_real_inclusive): optimize to multiply
-	  without Bignum.
-
-Sat May  7 07:58:02 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* process.c (rb_exec_getargs): honor the expected argument types
-	  over the conversion method.  the basic language functionality
-	  should be robust.  [ruby-core:75388] [Bug #12355]
-
-Fri May  6 08:16:26 2016  David Silva  <david.silva@digital.cabinet-office.gov.uk>
-
-	* enum.c (enum_find): [DOC] add more examples to the documentation
-	  of Enumerable#detect, to show that it equals to Enumerable#find.
-	  [Fix GH-1340]
-
-Thu May  5 18:08:31 2016  Yuichiro Kaneko  <yui-knk@ruby-lang.org>
-
-	* test/ruby/test_complexrational.rb: Remove duplicated raise.
-
-Thu May  5 14:41:05 2016  Yuichiro Kaneko  <yui-knk@ruby-lang.org>
-
-	* string.c (rb_str_sub): Fix a special match variable name.
-	  [ci skip]
-
-Thu May  5 12:22:17 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* vm_eval.c (rb_eval_cmd, rb_catch_obj): use TH_JUMP_TAG with the
-	  same rb_thread_t used for TH_PUSH_TAG, instead of JUMP_TAG with
-	  the current thread global variable.
-
-Thu May  5 10:49:33 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* random.c (fill_random_bytes_syscall): use arc4random_buf if
-	  available.
-
-Wed May  4 23:13:58 2016  Yuichiro Kaneko  <yui-knk@ruby-lang.org>
-
-	* numeric.c (fix_plus): Remove rb_nucomp_add prototype
-	  declaration.
-
-	* numeric.c (fix_mul): Remove rb_nucomp_mul prototype
-	  declaration.
-
-	* internal.h (rb_nucomp_add, rb_nucomp_mul): add prototype
-	  declarations.
-
-Wed May  4 18:38:00 2016  Kazuki Tsujimoto  <kazuki@callcc.net>
-
-	* lib/net/http/header.rb (Net::HTTPHeader#{each_header,each_name,
-	  each_capitalized_name,each_value,each_capitalized}): Return
-	  sized enumerators.
-
-	* test/net/http/test_httpheader.rb: add test for above.
-
-Wed May  4 17:53:15 2016  Kazuki Tsujimoto  <kazuki@callcc.net>
-
-	* lib/set.rb (Set#{delete_if,keep_if,collect!,reject!,select!,classify,divide},
-	  SortedSet#{delete_if,keep_if}): Return sized enumerators.
-
-	* test/test_set.rb: add test for above.
-
-Tue May  3 23:25:48 2016  Kazuhiro NISHIYAMA  <zn@mbf.nifty.com>
-
-	* numeric.c: [DOC] Update result of 123456789 ** -2.
-	  [ruby-dev:49606] [Bug #12339]
-
-Tue May  3 23:13:16 2016  Yuichiro Kaneko  <yui-knk@ruby-lang.org>
-
-	* internal.h (RCOMPLEX_SET_IMAG): undef RCOMPLEX_SET_IMAG
-	  instead of duplicated undef RCOMPLEX_SET_REAL.
-
-Tue May  3 22:55:07 2016  Yuichiro Kaneko  <yui-knk@ruby-lang.org>
-
-	* complex.c (rb_complex_set_imag): Fix to properly set imag
-	  of complex.
-
-Tue May  3 22:19:55 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* configure.in (warnflags): use -std=gnu99 instead of
-	  -std=iso9899:1999. [Feature #12336]
-
-Tue May  3 22:10:09 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* string.c (count_utf8_lead_bytes_with_word): Use __builtin_popcount
-	  only if it can use SSE 4.2 POPCNT whose latency is 3 cycle.
-
-	* internal.h (rb_popcount64): use __builtin_popcountll because now
-	  it is in fast path.
-
-Tue May  3 14:19:18 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* parse.y (new_if_gen): set newline flag to NODE_IF to trace all
-	  if/elsif statements.  [ruby-core:67720] [Bug #10763]
-
-Tue May  3 05:35:54 2016  Eric Wong  <e@80x24.org>
-
-	* process.c (disable_child_handler_fork_child):
-	  initialize handler for SIGPIPE for !POSIX_SIGNAL
-
-Mon May  2 23:03:42 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* win32/win32.c, include/ruby/win32.h (rb_w32_utruncate): implements new
-	  truncate alternative which accepts UTF-8 path.
-
-	* file.c (truncate): use above function.
-	  [Bug #12340]
-
-Mon May  2 20:59:21 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* re.c (str_coderange): to avoid function call when the string already
-	  has coderange information.
-
-	* re.c (rb_reg_prepare_enc): add shortcut path when the regexp has
-	  the same encoding of given string.
-
-	* re.c (rb_reg_prepare_re): avoid duplicated allocation of
-	  onig_errmsg_buffer.
-
-
-Mon May  2 12:34:52 2016  Tanaka Akira  <akr@fsij.org>
-
-	* test/ruby/test_refinement.rb (test_inspect): Use Integer instead of
-	  Fixnum.
-
-Mon May  2 06:58:38 2016  Tanaka Akira  <akr@fsij.org>
-
-	* complex.c: Don't refer rb_cFixnum and rb_cBignum.
-	  (k_fixnum_p): Use FIXNUM_P.
-	  (k_bignum_p): Use RB_TYPE_P.
-
-Mon May  2 01:27:59 2016  Tanaka Akira  <akr@fsij.org>
-
-	* test/ruby/test_numeric.rb (test_step): Use Integer::FIXNUM_MAX.
-
-Mon May  2 01:15:01 2016  Tanaka Akira  <akr@fsij.org>
-
-	* test/ruby/test_module.rb (test_name): Use Integer instead of Fixnum.
-
-Mon May  2 01:00:04 2016  Tanaka Akira  <akr@fsij.org>
-
-	* test/lib/test/unit/assertions.rb (assert_fixnum): Defined.
-	  (assert_bignum): Defined.
-
-	* test/ruby/test_bignum.rb: Use assert_bignum.
-
-	* test/ruby/test_integer_comb.rb: Use assert_fixnum and assert_bignum.
-
-	* test/ruby/test_optimization.rb: Ditto.
-
-Mon May  2 00:41:53 2016  Tanaka Akira  <akr@fsij.org>
-
-	* vm_trace.c (recalc_remove_ruby_vm_event_flags): Add a cast to
-	  avoid signed integer overflow.
-
-Mon May  2 00:06:04 2016  Tanaka Akira  <akr@fsij.org>
-
-	* test/lib/envutil.rb: Define Integer::{FIXNUM_MIN,FIXNUM_MAX}.
-
-	* test/ruby/test_bignum.rb: Use Integer::{FIXNUM_MIN,FIXNUM_MAX}.
-
-	* test/ruby/test_bignum.rb: Ditto.
-
-	* test/ruby/test_integer_comb.rb: Ditto.
-
-	* test/ruby/test_marshal.rb: Ditto.
-
-	* test/ruby/test_optimization.rb: Ditto.
-
-Sun May  1 23:59:59 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* array.c (rb_ary_sum): fix for mathn
-
-	* test/ruby/test_array.rb (test_sum): ditto.
-
-Sun May  1 23:51:54 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* test/lib/test/unit.rb (Options#non_options): fixed wrong regexp.
-	  if both positives and negatives were specified, positives had to
-	  be specified from the beginning.
-
-Sun May  1 21:00:07 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* win32/win32.c: drop Win2K support.
-
-Sun May  1 20:39:47 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* cont.c, hash.c, random.c, win32/win32.c: cleanup some Win9x/ME/NT4
-	  support leftovers.
-	  [fix GH-1328] patched by @cremno
-
-Sun May  1 07:30:44 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* string.c (search_nonascii): use nlz on big endian environments.
-
-	* internal.h (nlz_intptr): defined.
-
-Sun May  1 00:03:30 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* configure.in (__builtin_ctz): check.
-
-	* configure.in (__builtin_ctzll): check.
-
-	* internal.h (rb_popcount32): defined for ntz_int32.
-	  it can use __builtin_popcount but this function is not used on
-	  GCC environment because it uses __builtin_ctz.
-	  When another function uses this, using __builtin_popcount
-	  should be re-considered.
-
-	* internal.h (rb_popcount64): ditto.
-
-	* internal.h (ntz_int32): defined for ntz_intptr.
-
-	* internal.h (ntz_int64): defined for ntz_intptr.
-
-	* internal.h (ntz_intptr): defined as ntz for uintptr_t.
-
-	* string.c (search_nonascii): unroll and use ntz.
-
-Sat Apr 30 21:54:13 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (Init_Numeric): Gather Fixnum method definitions.
-
-Sat Apr 30 21:28:14 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (rb_int_div): Define Integer#/.
-
-	* bignum.c (rb_big_div): Don't define Bignum#/.
-
-	* lib/mathn.rb (Integer#/): Replace Integer#/ instead of Bignum#/.
-
-Sat Apr 30 21:11:08 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (rb_int_plus): Define Integer#+.
-
-	* bignum.c (rb_big_plus): Don't define Bignum#+.
-
-Sat Apr 30 21:01:20 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (rb_int_minus): Define Integer#-.
-
-	* bignum.c (rb_big_minus): Don't define Bignum#-.
-
-Sat Apr 30 20:53:33 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (rb_int_mul): Define Integer#*.
-
-	* bignum.c (rb_big_mul): Don't define Bignum#*.
-
-Sat Apr 30 20:30:44 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (rb_int_modulo): Define Integer#%.
-
-	* bignum.c (rb_big_modulo): Don't define Bignum#%.
-
-Sat Apr 30 20:17:08 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (int_equal): Define Integer#==.
-
-	* bignum.c (rb_big_eq): Don't define Bignum#==.
-
-Sat Apr 30 19:41:15 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (int_gt): Define Integer#>.
-
-	* bignum.c (rb_big_gt): Don't define Bignum#>.
-	  Renamed from big_gt.
-
-	* internal.h (rb_big_gt): Declared.
-
-Sat Apr 30 19:24:40 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (int_ge): Define Integer#>=.
-
-	* bignum.c (rb_big_ge): Don't define Bignum#>=.
-	  Renamed from big_ge.
-
-	* internal.h (rb_big_ge): Declared.
-
-Sat Apr 30 19:20:40 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* doc/standard_library.rdoc: Remove obsoleted classes and modules.
-
-Sat Apr 30 19:09:23 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (int_lt): Define Integer#<.
-
-	* bignum.c (rb_big_lt): Don't define Bignum#<.
-	  Renamed from big_lt.
-
-	* internal.h (rb_big_lt): Declared.
-
-Sat Apr 30 18:44:05 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (int_le): Define Integer#<=.
-
-	* bignum.c (rb_big_le): Don't define Bignum#<=.
-	  Renamed from big_le.
-
-	* internal.h (rb_big_le): Declared.
-
-Sat Apr 30 18:11:44 2016  Tanaka Akira  <akr@fsij.org>
-
-	* bignum.c (Init_Bignum): Define Integer::GMP_VERSION.
-
-Sat Apr 30 16:58:18 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (int_remainder): Define Integer#remainder.
-
-	* bignum.c (rb_big_remainder): Don't define Bignum#remainder.
-
-	* internal.h (rb_big_remainder): Declared.
-
-Sat Apr 30 15:29:24 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (rb_int_uminus): {Fixnum,Bignum}#-@ is unified into
-	  Integer.
-
-	* bignum.c (rb_big_uminus): Don't define Bignum#-@.
-
-Sat Apr 30 14:42:20 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (rb_int_idiv): {Fixnum,Bignum}#div is unified into
-	  Integer.
-
-	* bignum.c (rb_big_idiv): Don't define Bignum#div.
-
-Sat Apr 30 14:25:55 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (rb_int_modulo): {Fixnum,Bignum}#modulo is unified into
-	  Integer.
-
-	* bignum.c (rb_big_modulo): Don't define Bignum#modulo.
-
-Sat Apr 30 14:04:30 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (int_divmod): {Fixnum,Bignum}#divmod is unified into
-	  Integer.
-
-	* bignum.c (rb_big_divmod): Don't define Bignum#divmod.
-
-Sat Apr 30 13:20:00 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (int_fdiv): {Fixnum,Bignum}#fdiv is unified into
-	  Integer.
-
-	* bignum.c (rb_big_fdiv): Don't define Bignum#fdiv.
-
-Sat Apr 30 12:25:43 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (rb_int_pow): {Fixnum,Bignum}#** is unified into
-	  Integer.
-
-	* bignum.c (rb_big_pow): Don't define Bignum#**.
-
-Sat Apr 30 12:28:59 2016  Tanaka Akira  <akr@fsij.org>
-
-	* bignum.c (rb_big_comp): Renamed from rb_big_neg.
-
-	* numeric.c (fix_comp): Renamed from fix_rev.
-
-Sat Apr 30 12:25:43 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (int_comp): {Fixnum,Bignum}#~ is unified into
-	  Integer.
-
-	* bignum.c (rb_big_neg): Don't define Bignum#~.
-
-	* internal.h (rb_big_neg): Declared.
-
-Sat Apr 30 12:07:42 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (int_and): {Fixnum,Bignum}#& is unified into
-	  Integer.
-
-	* bignum.c (rb_big_and): Don't define Bignum#&.
-
-Sat Apr 30 11:56:15 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/thread: removed dummy extension library.  thread_sync.c
-	  provides "thread.rb" already.
-
-Sat Apr 30 11:53:48 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (int_or): {Fixnum,Bignum}#| is unified into
-	  Integer.
-
-	* bignum.c (rb_big_or): Don't define Bignum#|.
-
-Sat Apr 30 11:18:47 2016  Yuichiro Kaneko  <yui-knk@ruby-lang.org>
-
-	* vm_trace.c: Fix typos. [ci skip]
-
-Sat Apr 30 10:09:04 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/pty/pty.c (establishShell): honor USER environment variable
-	  and login name over uid, one uid can be shared by some login
-	  names.
-
-Fri Apr 29 22:40:28 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* doc/maintainers.rdoc (ext/io/nonblock): still maintained, as
-	  well as ext/io/wait, which is the origin.
-
-Fri Apr 29 21:18:12 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* doc/maintainers.rdoc (ext/win32): of course, it's still maintained.
-
-Fri Apr 29 21:03:10 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* gems/bundled_gems: Update latest gems, test-unit-3.1.8 and rake-11.1.2.
-
-Fri Apr 29 20:43:02 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* doc/maintainers.rdoc: Update latest maintainers list on Ruby 2.4
-
-Fri Apr 29 19:52:45 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* doc/maintainers.rdoc: Removed deprecated entries. These are already deleted.
-
-Fri Apr 29 19:48:45 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* doc/maintainers.rdoc: Removed Ruby 1.8 entries. It's not necessary to
-	  Ruby 2.4 or later.
-
-Thu Apr 28 17:03:17 2016  Nicholas Maccharoli  <nmaccharoli@gmail.com>
-
-	* hash.c (rb_hash_update_{block,func}_callback): dry up hash
-	  update callback code.  [Fix GH-1338]
-
-Thu Apr 28 16:52:05 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* re.c (rb_reg_prepare_enc): use rb_enc_asciicompat(enc) instead of
-	  rb_enc_str_asciicompat_p(str) to avoid useless rb_enc_get(str) call.
-
-Thu Apr 28 16:33:41 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/optparse.rb: [DOC] fix example code.  base on the code by
-	  Semyon Gaivoronskiy in [ruby-core:75224].  [Bug #12323]
-
-Thu Apr 28 09:33:03 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/rubygems.rb, lib/rubygems/*, test/rubygems/*: Update rubygems-2.6.4.
-	  Please see entries of 2.6.4 on
-	  https://github.com/rubygems/rubygems/blob/master/History.txt
-
-Thu Apr 28 04:49:07 2016  Rei Odaira  <Rei.Odaira@gmail.com>
-
-	* configure.in (rb_cv_lgamma_r_pm0): check if lgamma_r(+0.0)
-	  returns positive infinity, in addition to lgamma_r(-0.0).
-	  AIX returns an incorrect result of negative infinity.
-
-	* math.c (ruby_lgamma_r): handle +0.0, in addition to -0.0.
-
-Thu Apr 28 01:11:14 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* time.c: define _DEFAULT_SOURCE because glibc 2.20 deprecates
-	  _BSD_SOURCE.
-	  https://sourceware.org/glibc/wiki/Release/2.20
-
-Thu Apr 28 00:27:55 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (int_xor): {Fixnum,Bignum}#^ is unified into
-	  Integer.
-
-	* bignum.c (rb_big_xor): Don't define Bignum#^.
-
-Wed Apr 27 20:53:59 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (int_aref): {Fixnum,Bignum}#[] is unified into
-	  Integer.
-
-	* bignum.c (rb_big_aref): Don't define Bignum#<<.
-
-	* internal.h (rb_big_aref): Declared.
-
-Wed Apr 27 16:10:35 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* tool/instruction.rb: fix to follow current implementation.
-
-Wed Apr 27 15:47:54 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/stringio/stringio.c (strio_s_new): warn if a block is given,
-	  as well as IO.new.
-
-Wed Apr 27 14:29:47 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* error.c (ruby_only_for_internal_use): raise fatal error when
-	  deprecated function only for internal use is called, not just a
-	  warning.
-
-Tue Apr 26 23:42:30 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* tool/redmine-backporter.rb (rel): should not raise exceptions even if
-	  the user input is wrong.  only reports the error and continue process.
-
-Tue Apr 26 23:35:23 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ruby.c (process_options): convert -e script to the encoding
-	  given by a command line option on Windows.  assume it is the
-	  expected encoding.  [ruby-dev:49461] [Bug #11900]
-
-Tue Apr 26 21:11:02 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (rb_int_lshift): {Fixnum,Bignum}#<< is unified into
-	  Integer.
-
-	* bignum.c (rb_big_lshift): Don't define Bignum#<<.
-
-Tue Apr 26 20:59:40 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (rb_int_rshift): {Fixnum,Bignum}#>> is unified into
-	  Integer.
-
-	* bignum.c (rb_big_rshift): Don't define Bignum#>>.
-
-Tue Apr 26 20:46:16 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (int_size): {Fixnum,Bignum}#size is unified into Integer.
-
-	* bignum.c (rb_big_size_m): Don't define Bignum#size.
-
-	* internal.h (rb_big_size_m): Declared.
-
-Tue Apr 26 20:09:08 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (rb_int_bit_length): {Fixnum,Bignum}#bit_length is
-	  unified into Integer.
-
-	* bignum.c (rb_big_bit_length): Don't define Bignum#bit_length.
-
-	* internal.h (rb_big_bit_length): Declared.
-
-Tue Apr 26 19:56:16 2016  Tanaka Akira  <akr@fsij.org>
-
-	* numeric.c (int_abs): Integer#{abs,magnitude} moved from
-	  Fixnum and Bignum.
-
-	* bignum.c (rb_big_abs): Don't define Bignum#{abs,magnitude}.
-
-	* internal.h (rb_big_abs): Declared.
-
-Mon Apr 25 14:39:11 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/rbconfig/sizeof/extconf.rb: just check the existence of each
-	  types, to reduce configuration time, especially cross-compiling.
-
-	* template/sizes.c.tmpl: calculate sizes of checked types at
-	  compilation time.
-
-Mon Apr 25 11:27:27 2016  Marcus Stollsteimer  <sto.mar@web.de>
-
-	* doc/extension.rdoc: Improvements to english grammars.
-	  [Bug #12246][ruby-core:74792][ci skip]
-
-Mon Apr 25 11:17:50 2016  Marcus Stollsteimer  <sto.mar@web.de>
-
-	* encoding.c: Fix return value of `Encoding::ISO8859_1.name`
-	  [Bug #12313][ruby-core:75147][ci skip]
-	* ext/bigdecimal/bigdecimal.c: Fix code sample of `BigDecimal.new`
-
-Sun Apr 24 23:29:16 2016  Rei Odaira  <Rei.Odaira@gmail.com>
-
-	* configure.in: add missing -lm for AIX.
-
-Sun Apr 24 18:33:58 2016  Kazuki Tsujimoto  <kazuki@callcc.net>
-
-	* vm_insnhelper.c (INLINE): disable r54738 if __NO_INLINE__ is defined.
-	  It caused "undefined reference to `vm_getivar'".
-
-Sun Apr 24 09:32:12 2016  Yuichiro Kaneko  <yui-knk@ruby-lang.org>
-
-	* test/ruby/test_array.rb: Add test cases for Array#sum with
-	  non-numeric objects.
-
-Sun Apr 24 04:21:27 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* vm_insnhelper.c (INLINE): define as `inline` when it is optimized.
-	  define as `static inline` when it is not optimized to keep
-	  the symbol generated.
-
-	* vm_insnhelper.c (vm_getivar): use `INLINE` to force inline
-	  so that a compiler inlines it into vm_getinstancevariable
-	  and optimizes out is_attr and related branches.
-
-	* vm_insnhelper.c (vm_getivar): use `inline` to recommend inline.
-	  Without this vm1_ivar_set is degraded.
-
-	  benchmark results:
-	  minimum results in each 5 measurements.
-	  Execution time (sec)
-	  name    ruby 2.4.0dev (2016-04-23 trunk 54727) [x86_64-linux]   ruby 2.4.0dev (2016-04-23 trunk 54733) [x86_64-linux]       built-ruby
-	  loop_whileloop 0.641                                                   0.642 0.646
-	  vm1_ivar* 1.002                                                   0.999 0.831
-	  vm1_ivar_set* 0.369                                                   1.106 0.362
-
-	  Speedup ratio: compare with the result of `ruby 2.4.0dev (2016-04-23
-	  trunk 54727) [x86_64-linux]' (greater is better)
-	  name    ruby 2.4.0dev (2016-04-23 trunk 54733) [x86_64-linux]
-	  built-ruby
-	  loop_whileloop
-	  0.998        0.991
-	  vm1_ivar*
-	  1.003        1.205
-	  vm1_ivar_set*
-	  0.334        1.018
-
-Sat Apr 23 18:01:21 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* vm_insnhelper.c (vm_getivar): specify inline instead of static inline.
-	  vm_getivar is called by vm_call_ivar and vm_getinstancevariable.
-	  At least with GCC 4.8 and 5.3 on Linux, they are inlining it into
-	  vm_call_ivar but not vm_getinstancevariable.
-	  By `inline`, they correctly inline it and gains performance.
-
-	  Speedup ratio: compare with the result of `ruby 2.4.0dev (2016-04-23
-	  trunk 54727) [x86_64-linux]' (greater is better)
-	  name    built-ruby
-	  loop_whileloop       1.001
-	  vm1_ivar*            1.189
-	  vm1_ivar_set*        1.024
-
-	  Note the `inline`'s meaning is different between old GCC
-	  and C99. Old GCC's inline means C99's extern inline.
-	  https://gcc.gnu.org/onlinedocs/gcc/Inline.html
-	  Since Ruby specify -std=iso9899:1999, it works like C99.
-
-Sat Apr 23 16:11:39 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* include/ruby/ruby.h (rb_mul_size_overflow): use UNLIKELY
-	  by user side to improve generality.
-
-Sat Apr 23 16:10:02 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* include/ruby/ruby.h (RB_LIKELY): use prefix in ruby.h.
-
-	* intern.h (LIKELY): define with RB_LIKELY.
-
-Sat Apr 23 13:27:25 2016  Yuichiro Kaneko  <yui-knk@ruby-lang.org>
-
-	* NEWS: Add descriptions for Time#to_time updates.
-	  [Bug #12271]
-
-Sat Apr 23 13:21:24 2016  Yuichiro Kaneko  <yui-knk@ruby-lang.org>
-
-	* NEWS: Add descriptions for DateTime#to_time updates.
-	  [Bug #12189]
-
-Sat Apr 23 11:21:27 2016  Marcus Stollsteimer  <sto.mar@web.de>
-
-	* ext/date/date_core.c (Init_date_core): [DOC] Convert DateTime
-	  documentation to RDoc from Markdown.
-	  [ruby-core:75136] [Bug #12311]
-
-Sat Apr 23 09:03:35 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ruby.c: cygwin does not use w32_cmdvector, command line can be
-	  other than UTF-8.  [ruby-dev:49519] [Bug #12184]
-
-Sat Apr 23 01:00:03 2016  Rei Odaira  <Rei.Odaira@gmail.com>
-
-	* configure.in: don't use the system-provided round(3) on AIX.
-	  In AIX, round(0.49999999999999994) returns 1.0.
-	  Use round() in numeric.c instead.
-
-Fri Apr 22 21:00:44 2016  Tanaka Akira  <akr@fsij.org>
-
-	* test/ruby/test_time_tz.rb: Tests depends on Europe/Moscow removed
-	  to avoid test failures due to the tzdata change.
-	  https://github.com/eggert/tz/commit/8ee11a301cf173afb0c76e0315b9f9ec8ebb9d95
-	  Found by naruse.
-
-Fri Apr 22 20:18:40 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* include/ruby/ruby.h (rb_mul_size_overflow): added to handle
-	  mul overflow efficiently.
-
-	* include/ruby/ruby.h (rb_alloc_tmp_buffer2): use rb_mul_size_overflow
-	  and avoid division where it can define DSIZE_T.
-
-	* gc.c (xmalloc2_size): moved from ruby.h and use rb_mul_size_overflow.
-
-Fri Apr 22 20:34:04 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* time.c (time_asctime): [DOC] add ctime example, not only
-	  asctime.  [ruby-core:75126] [Bug #12310]
-
-Fri Apr 22 18:44:32 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* variable.c: use uint32_t instead of long to avoid confusion about
-	  the type of ivtbl->numiv.
-
-Fri Apr 22 15:09:27 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* eval_jump.c (exec_end_procs_chain): restore previous error info
-	  for each end procs.  [ruby-core:75038] [Bug #12302]
-
-Fri Apr 22 15:04:56 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* tool/redmine-backporter.rb: the fullpath of merger.rb is too long to
-	  copy&paste on Windows.  show shorter name instead on the platform.
-	  I'm sure that the user of this command on Windows is only me.
-
-Fri Apr 22 14:52:04 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* tool/merger.rb: remove temporary file.
-
-Fri Apr 22 11:27:03 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/net/http.rb: Improve documentation for SSL requests via GET method.
-	  [fix GH-1325][ci skip] Patch by @jsyeo
-
-Fri Apr 22 10:51:13 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/webrick/ssl.rb: Support to add SSLCiphers option.
-	  [fix GH-1321] Patch by @rhadoo
-
-Fri Apr 22 10:43:19 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* file.c, win32/file.c: Removed obsoleted safe level checks.
-	  [fix GH-1327] Patch by @cremno
-
-Fri Apr 22 10:01:48 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* benchmark/bm_so_meteor_contest.rb: fix a typo.
-	  [fix GH-1330][ci skip] Patch by @sachin21
-
-Fri Apr 22 04:57:01 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* gc.c (rb_alloc_tmp_buffer_with_count): added like xmalloc2 to
-	  avoid duplicated check of size.
-
-	* gc.c (ruby_xmalloc2): added to keep separate layers.
-
-	* include/ruby/ruby.h (rb_alloc_tmp_buffer2): added to check
-	  the size more statically.
-
-Fri Apr 22 04:54:40 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* include/ruby/ruby.h (LIKELY): moved from internal.h.
-
-	* include/ruby/ruby.h (UNLIKELY): ditto.
-
-Thu Apr 21 01:44:19 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* gc.c (objspace_malloc_prepare): remove size check because it is
-	  used by objspace_xmalloc and objspace_xcalloc.
-	  objspace_xmalloc introduces its own check in this commit.
-	  objspace_xcalloc checks with xmalloc2_size (ruby_xmalloc2_size).
-
-	* gc.c (objspace_xmalloc0): common xmalloc function.
-
-	* gc.c (objspace_xmalloc): introduce its own size check.
-
-	* gc.c (objspace_xmalloc2): separated from ruby_xmalloc2 to clarify
-	  the layer who has the responsibility to check the size.
-
-	* gc.c (objspace_xrealloc): remove duplicated size check.
-
-	* gc.c (ruby_xmalloc2): use objspace_xmalloc2.
-
-	* include/ruby/ruby.h (ruby_xmalloc2_size): follow the size limit
-	  as SSIZE_MAX. Note that ISO C says size_t is unsigned integer.
-
-Thu Apr 21 12:14:04 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* configure.in: check if succeeded in creating config.h.
-
-	* tool/ifchange: ignore failures when TEST_COLORS unmatched. just
-	  use the default value if expected name is not contained in it.
-	  [ruby-core:75046] [Bug #12303]
-
-Wed Apr 20 17:33:31 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/cgi/escape/escape.c (cgiesc_unescape): define unescape
-	  method instead of _unescape, and should pass the optional
-	  argument to the super method.
-
-	* lib/cgi/util.rb (CGI::Util#_unescape): remove intermediate
-	  method.
-
-Wed Apr 20 15:52:28 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* error.c (syntax_error_initialize): move the default message,
-	  "compile error", from parse.y.  the default parameter should
-	  belong to the class definition.
-
-	* parse.y (yycompile0): use the default parameter.
-
-Wed Apr 20 10:25:53 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* compile.c (append_compile_error): use rb_syntax_error_append.
-
-	* error.c (rb_syntax_error_append): append messages into a
-	  SyntaxError exception instance.
-
-	* parse.y (yycompile0): make new SyntaxError instance in main
-	  mode, otherwise error_buffer should be a SyntaxError if error
-	  has occurred.
-
-Tue Apr 19 17:42:47 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* error.c (err_vcatf): rename, and separate appending message from
-	  creating a string buffer.
-
-	* error.c (rb_syntax_error_append): merge rb_error_vsprintf and
-	  rb_compile_err_append.
-
-	* parse.y (parser_compile_error): use rb_syntax_error_append.
-
-Tue Apr 19 13:46:19 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* compile.c (append_compile_error, compile_bug): pass iseq and get
-	  error info and file from it, not by the thread error info.
-
-	* error.c (rb_report_bug_valist): take va_list instead of variadic
-	  arguments, and just report the bug but not abort.
-
-Tue Apr 19 13:18:12 2016  Naotoshi Seo  <sonots@gmail.com>
-
-	* lib/time.rb: revert r54167 because it would break
-	  backward compatibilities, and it is documented that
-	  Time.parse does not take into account time zone
-	  abbreations other than ones described in RFC 822
-
-Tue Apr 19 13:12:03 2016  Naotoshi Seo  <sonots@gmail.com>
-
-	* ChangeLog: Fix dates of previous commits
-
-Tue Apr 19 12:45:03 2016  Naotoshi Seo  <sonots@gmail.com>
-
-	* ChangeLog: Add descriptions for logger updates
-	* NEWS: Add descriptions for logger updates
-
-Tue Apr 19 12:45:02 2016  Naotoshi Seo  <sonots@gmail.com>
-
-	* lib/logger.rb: Add shift_period_suffix option
-
-Tue Apr 19 12:45:01 2016  Naotoshi Seo  <sonots@gmail.com>
-
-	* lib/logger.rb: Allow specifying logger parameters in constructor
-	  such as level, progname, datetime_format, formatter.
-
-Mon Apr 18 16:07:01 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* compile.c (iseq_peephole_optimize): should not replace the
-	  current target INSN, not to follow the replaced dangling link in
-	  the caller.  [ruby-core:74993] [Bug #11816]
-
-Mon Apr 18 12:56:31 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* numeric.c (flo_truncate): add an optional parameter, digits, as
-	  well as Float#round.  [Feature #12245]
-
-	* numeric.c (int_truncate): add an optional parameter, digits, as
-	  well as Integer#round.  [Feature #12245]
-
-Sun Apr 17 04:18:56 2016  CHIKANAGA Tomoyuki  <nagachika@ruby-lang.org>
-
-	* tool/redmine-backporter.rb: revisions are strings.
-
-Sat Apr 16 14:26:49 2016  Yuichiro Kaneko  <yui-knk@ruby-lang.org>
-
-	* ext/date/date_core.c : remove not used f_getlocal macro.
-	  After r54553 f_getlocal macro is not used.
-
-Sat Apr 16 14:15:24 2016  Yuichiro Kaneko  <yui-knk@ruby-lang.org>
-
-	* ext/date/date_core.c : remove not used f_utc6 macro.
-	  After r54169 f_utc6 macro is not used.
-
-Sat Apr 16 10:00:11 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* struct.c (struct_make_members_list, rb_struct_s_def): member
-	  names should be unique. [ruby-core:74971] [Bug #12291]
-
-	* struct.c (struct_make_members_list): extract making member name
-	  list from char* va_list, with creating symbols without
-	  intermediate IDs.
-
-Sat Apr 16 01:33:27 2016  CHIKANAGA Tomoyuki  <nagachika@ruby-lang.org>
-
-	* tool/redmine-backporter.rb: sort revisions.
-
-Sat Apr 16 01:16:02 2016  Tanaka Akira  <akr@fsij.org>
-
-	* array.c (rb_ary_sum): Don't yield same element twice.
-	  Found by nagachika.
-
-Sat Apr 16 01:03:32 2016  Tanaka Akira  <akr@fsij.org>
-
-	* array.c (rb_ary_sum): Fix SEGV by [1/2r, 1].sum.
-
-Fri Apr 15 23:52:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* rational.c (rb_rational_plus): rename from rb_rational_add
-	  to be aligned with rb_fix_plus.
-
-	* array.c (rb_ary_sum): ditto.
-
-	* internal.h: ditto.
-
-Fri Apr 15 23:42:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* rational.c (rb_rational_add): rename from nurat_add.
-
-	* array.c (rb_ary_sum): use rb_rational_add directly.
-
-	* test/ruby/test_array.rb (test_sum): add assertions for an array of
-	  Rational values.
-
-Fri Apr 15 22:31:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* array.c (rb_ary_sum): apply the precision compensated algorithm
-	  for an array in which Rational and Float values are mixed.
-
-	* test/ruby/test_array.rb (test_sum): add assertions for the above
-	  change.
-
-Fri Apr 15 22:30:01 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* thread.c (rb_thread_setname): defer setting native thread name
-	  set in initialize until the native thread is created.
-	  [ruby-core:74963] [Bug #12290]
-
-Fri Apr 15 20:27:16 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/irb/ext/save-history.rb: Fix NoMethodError when method is not defined.
-
-Fri Apr 15 15:38:58 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* common.mk (benchmark): order options for built-ruby and compare-ruby.
-
-Fri Apr 15 14:14:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* test/ruby/test_array.rb (test_sum): add assertions for Rational and
-	  Complex numbers.
-
-Fri Apr 15 10:07:11 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/io/console/console.c (console_key_pressed_p): raise the same
-	  exception, "unknown virtual key code", for names with nul chars.
-	  though console_win32_vk() considers the length and can deal with
-	  nul chars, rb_sprintf() raised at PRIsVALUE previously, so quote
-	  it if it is unprintable.
-
-Fri Apr 15 09:02:58 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/io/console/console.c (rb_sym2str): fallback definition for
-	  older ruby.  [ruby-core:74953] [Bug #12284]
-
-Thu Apr 14 21:46:36 2016  Tanaka Akira  <akr@fsij.org>
-
-	* array.c (rb_ary_sum): Support the optional argument, init, and
-	  block.
-
-Thu Apr 14 19:02:41 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* lib/irb/ext/save-history.rb: suppress warning: method redefined;
-	  discarding old save_history=.
-
-Thu Apr 14 14:58:14 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/tk/tkutil/tkutil.c (tk_hash_kv): the third argument can be
-	  nil not only an Array.  reported by @windwiny at
-	  https://github.com/ruby/ruby/commit/cdaa94e#commitcomment-17096618
-
-Thu Apr 14 14:28:55 2016  cremno phobia  <cremno@mail.ru>
-
-	* cont.c (fiber_initialize_machine_stack_context): fix wrong
-	  _MSC_VER check, should be decimal but not hexadecimal.
-	  [ruby-core:74936] [Bug #12279]
-
-Wed Apr 13 22:51:38 2016  Tanaka Akira  <akr@fsij.org>
-
-	* array.c (rb_ary_sum): Array#sum is implemented.
-	  Kahan's compensated summation algorithm for precise sum of float
-	  numbers is moved from ary_inject_op in enum.c.
-
-	* enum.c (ary_inject_op): Don't specialize for float numbers.
-
-	  [ruby-core:74569] [Feature #12217] proposed by mrkn.
-
-Wed Apr 13 15:56:35 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* numeric.c (flo_ceil): add an optional parameter, digits, as
-	  well as Float#round.  [Feature #12245]
-
-	* numeric.c (flo_floor): add an optional parameter, digits, as
-	  well as Float#round.  [Feature #12245]
-
-	* numeric.c (int_ceil): add an optional parameter, digits, as
-	  well as Integer#round.  [Feature #12245]
-
-	* numeric.c (int_floor): add an optional parameter, digits, as
-	  well as Integer#round.  [Feature #12245]
-
-Wed Apr 13 14:47:47 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* file.c (Init_File): add alias File.empty? to File.zero?.
-	  [Feature #9969]
-
-Wed Apr 13 14:36:24 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* parse.y (assign_in_cond): allow multiple assignment in
-	  conditional expression.  [Feature #10617]
-
-Wed Apr 13 14:11:59 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* bignum.c (rb_big_size): add wrapper function of BIGSIZE and
-	  rename the method function with _m suffix.
-
-	* numeric.c (int_round_zero_p): extracted from rb_int_round.
-	  optimize for Bignum, and convert VALUE returned by Numeric#size
-	  to long.
-
-Wed Apr 13 12:00:08 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* test/ruby/test_basicinstructions.rb: add a test to check access
-	  instance variables on special const objects.
-
-	  All of such objects are frozen, so that we can not set instance
-	  variables for them. But we can read instance variables and return
-	  default value (nil).
-
-Tue Apr 12 20:40:35 2016  Kaneko Yuichiro  <spiketeika@gmail.com>
-
-	* ext/date/date_core.c (time_to_time): should preserve timezone
-	  info.  [ruby-core:74889] [Bug #12271]
-
-Tue Apr 12 11:51:18 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* compile.c (new_label_body): initialize bit fields, since
-	  compile_data_alloc does not clear the memory.  [Bug #12082]
-
-Mon Apr 11 20:18:43 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* vm_backtrace.c (frame2klass): filter only for imemo_ment.
-	  T_IMEMO/imemo_iseq can be passed here.
-
-Mon Apr 11 17:43:04 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* compile.c (iseq_optimize): disable tail call optimization in
-	  rescued, rescue, and ensure blocks.
-	  [ruby-core:73871] [Bug #12082]
-
-Mon Apr 11 06:54:39 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* file.c (apply2files): apply to a VALUE vector instead of a
-	  temporary array.
-
-Sun Apr 10 20:54:16 2016  Joe Swatosh  <joe.swatosh@gmail.com>
-
-	* ext/win32/lib/win32/registry.rb (DeleteValue, DeleteKey): fix
-	  API names.  [ruby-core:74863] [Bug #12264]
-
-Sun Apr 10 17:47:42 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* file.c (rb_realpath_internal): no argument conversions since
-	  this internal function does not need to_path and encoding
-	  conversions, not to be affected by the default internal
-	  encoding.
-
-Sat Apr  9 10:03:12 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* load.c (rb_f_load): raise with the original path name before
-	  encoding conversion.
-
-Sat Apr  9 02:05:10 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* bignum.c (rb_cstr_parse_inum): [EXPERIMENTAL] new function to
-	  parse integer in C-string with length.  the name and the
-	  arguments may be changed in the future.
-
-	* bignum.c (rb_str_to_inum): preserve encoding of the argument in
-	  error messages, and no longer needs to copy non-terminated
-	  strings.
-
-	* bignum.c (rb_str2big_{poweroftwo,normal,karatsuba,gmp}): ditto.
-
-Thu Apr  7 19:04:03 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* doc/regexp.rdoc (comments): [DOC] terminators cannot appear in
-	  comments.  [ruby-core:74838] [Bug #12256]
-
-Thu Apr  7 11:24:14 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/tk/tkutil/tkutil.c (cbsubst_initialize): fix out-of-bound
-	  access when no arguments given.  `p Tk::Event.new` crashed.
-
-Fri Apr  1 01:26:00 2016  Benoit Daloze  <eregontp@gmail.com>
-
-	* ext/coverage/coverage.c: Fully reset coverage to not persist global state.
-	  It was returning old file coverages as empty arrays to the user.
-	  [ruby-core:74596] [Bug #12220]
-
-	* ext/coverage/coverage.c (rb_coverages): remove unused static state.
-
-	* thread.c: Moved and renamed coverage_clear_result_i to reset_coverage_i.
-
-	* test/coverage/test_coverage.rb: improve precision of tests.
-
-Wed Apr  6 22:41:31 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* configure.in (rb_cv_lgamma_r_m0): fix the condition for
-	  lgamma_r(-0.0).  [Bug #12249]
-
-Wed Apr  6 17:38:42 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* tool/downloader.rb (RubyGems.download): follow the change of the
-	  rubygems ssl_certs directory tree introduced by previous commit.
-
-Wed Apr  6 15:00:27 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/rubygems.rb, lib/rubygems/*, test/rubygems/*: Update rubygems-2.6.3.
-	  Please see entries of 2.6.3 on
-	  https://github.com/rubygems/rubygems/blob/master/History.txt
-
-Wed Apr  6 14:13:28 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* configure.in (rb_cv_lgamma_r_m0): check if lgamma_r(-0.0)
-	  returns negative infinity.  [Bug #12249]
-
-	* math.c (ruby_lgamma_r): define by the configured result.
-
-Wed Apr  6 10:56:15 2016  Anton Davydov  <antondavydov.o@gmail.com>
-
-	* lib/logger.rb (Logger#level=): remove unnecessary local
-	  variable.
-
-	* lib/logger.rb (Logger#initialize, Logger#reopen): [DOC] mention
-	  the default values.  cherrypicked from [GH-1319].
-
-Wed Apr  6 10:17:53 2016  cremno phobia  <cremno@mail.ru>
-
-	* math.c (ruby_lgamma_r): missing/lgamma_r.c is used on Windows,
-	  since msvcrt does not provide it.
-
-	* missing/lgamma_r.c (lgamma_r): fix lgamma(-0.0).
-	  [ruby-core:74823] [Bug #12249]
-
-Wed Apr  6 01:22:55 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* math.c (ruby_lgamma_r): mswin's lgamma_r also seems to be wrong.
-	  cf. [Bug #12249]
-
-Wed Apr  6 00:53:31 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* math.c (ruby_lgamma_r): fix lgamma(-0.0) on mingw and OSX.
-
-	* math.c (ruby_tgamma): fix tgamma(-0.0) on mingw.
-	  [ruby-core:74817] [Bug #12249]
-
-Tue Apr  5 14:50:28 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* ext/nkf/nkf-utf8/nkf.c (mime_putc): fix typo.
-	  [Bug #12202] [ruby-core:74802]
-
-Tue Apr  5 00:06:44 2016  Aeris  <aeris@imirhil.fr>
-
-	* ext/openssl/ossl_ssl.c (ossl_ssl_tmp_key): Access to ephemeral
-	  TLS session key in case of forward secrecy cipher.  Only
-	  available since OpenSSL 1.0.2.  [Fix GH-1318]
-
-	* ext/openssl/extconf.rb: Check for SSL_get_server_tmp_key.
-
-Mon Apr  4 23:37:05 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* vm_core.h (rb_vm_struct): make at_exit a single linked list but
-	  not RArray, not to mark the registered functions by the write
-	  barrier.  based on the patches by Evan Phoenix.
-	  [ruby-core:73908] [Bug #12095]
-
-Mon Apr  4 17:43:45 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c: change default value of
-	  RUBY_GC_HEAP_FREE_SLOTS_MIN_RATIO 0.3 -> 0.2
-	  RUBY_GC_HEAP_FREE_SLOTS_MAX_RATIO 0.8 -> 0.65
-
-	  These values are same as Ruby 2.0.0.
-
-	  This change cause GC counts.
-	  However, generational GC reduced each (minor) GC time and
-	  increase memory locality. So that not so big impact on my
-	  benchmarking results.
-	  (surprisingly, this fix speed up programs on some cases)
-
-	  You can change these values by environment variables
-	  if you feel wrong.
-
-Mon Apr  4 17:36:52 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c (get_envparam_double): take an upper_bound.
-
-	  And also take an accept_zero flag which allow to accept zero
-	  even if lower_bound is set.
-
-	* gc.c (ruby_gc_set_params): fix parameters.
-
-	  RUBY_GC_HEAP_FREE_SLOTS_MAX_RATIO set 0.9 as *lower_bound*, so that
-	  it should be upper_bound.
-	  Set RUBY_GC_HEAP_FREE_SLOTS_MIN_RATIO as lower bound.
-
-	  Also set lower/upper bound of RUBY_GC_HEAP_FREE_SLOTS_GOAL_RATIO to
-	  RUBY_GC_HEAP_FREE_SLOTS_MIN/MAX_RATIO.
-
-Mon Apr  4 16:41:32 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* vm.c (Init_VM): should pass tokens.
-
-Sun Apr  3 09:34:29 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* numeric.c (flodivmod): round division if it is a finite number
-	  and module is required.
-
-	* numeric.c (dbl2ival): do not round here.
-
-	* numeric.c (flo_ceil): use dbl2ival.
-
-	* numeric.c (flo_round): round explicitly.
-
-Sat Apr  2 15:24:18 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/intern.h (rb_check_arity): returns argc.
-
-Fri Apr  1 20:58:33 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode/case-folding.rb, casefold.h: Data generation to implement
-	  swapcase functionality for titlecase characters. Swapcase isn't defined
-	  by Unicode, because the purpose/usage of swapcase is unclear anyway.
-	  The implementation follows a proposal from Nobu, swapping the case of
-	  each component of a titlecase character individually.
-	  This means that the titlecase characters have to be decomposed.
-
-	* enc/unicode.c: Code using the above data.
-
-	* test/ruby/enc/test_case_mapping.rb: Tests for the above.
-
-Fri Apr  1 14:55:28 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* configure.in (AC_CONFIG_FILES): $srcdir/.git can be a file pointing
-	  the real git_dir, such as when the git working tree is a "linked
-	  working tree" (a working tree created by git-worktree). So use
-	  git-rev-parse --git-dir to check if $srcdir is the top-level of a git
-	  repository, not just checking if the $srcdir/.git directory does exist
-	  or not.  [ruby-core:74759] [Bug #12239]
-
-	* tool/change_maker.rb: use tool/vcs.rb to detect VCS. This used to have
-	  its own VCS detection code, while we have tool/vcs.rb.
-
-	* tool/vcs.rb (detect): remove code duplication
-
-Fri Apr  1 04:50:44 2016  Eric Wong  <e@80x24.org>
-
-	* ext/openssl/ossl_ssl.c (ossl_sslctx_s_alloc):
-	  enable SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER by default
-	  [Bug #12126]
-
-Fri Apr  1 01:13:55 2016  Benoit Daloze  <eregontp@gmail.com>
-
-	* thread.c (update_coverage): Do not track coverage in loaded files
-	  after Coverage.result. Avoids out-of-bounds access. [Bug #12237]
-
-	* ext/coverage/coverage.c (coverage_clear_result_i): document.
-
-Thu Mar 31 19:16:16 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c: need to set initial value of GC_HEAP_FREE_SLOTS_GOAL_RATIO.
-
-Thu Mar 31 17:50:27 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c: change additional allocation policy.
-
-	  Introduce new environment variable
-	  RUBY_GC_HEAP_FREE_SLOTS_GOAL_RATIO (goal_ratio) to calculate the
-	  ratio of additional memory.
-
-	  Before this change, we add pages with the following formula
-	  (when free_slots < total_pages * RUBY_GC_HEAP_FREE_SLOTS_MIN_RATIO):
-	    next_pages = total_pages * RUBY_GC_HEAP_GROWTH_FACTOR
-
-	  This addition can allocate too much.
-
-	  With this change, we increase pages to satisfy the following formula:
-	    next_free_slots = next_total_slots * goal_ratio
-	  where
-	    next_free_slots = free_slots + adding_slots
-	    next_total_slots = total_slots + adding_slots.
-
-	  If you want to prepare many free slots, increase this ratio.
-
-	  If this variable is 0, then simply multiply
-	  RUBY_GC_HEAP_GROWTH_FACTOR.
-
-	* gc.c (get_envparam_double): enable to accept 0.
-
-Thu Mar 31 17:48:25 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c (gc_marks_finish): fix syntax error.
-
-Thu Mar 31 16:49:36 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c: simplify allocate/free detecting logic at the end of marking.
-
-	  Before this change, heap_pages_min_slots are calculated at the
-	  beginning sweeping phase. And this value is used at the end of
-	  *next* marking phase.
-
-	  To simplify it, we use this value at the end of this marking phase.
-	  It means that we don't need to store this value as global state.
-
-	  Also heap_pages_max_slots is calculated at the begging of sweeping
-	  phase and used at the end of sweeping phase.
-	  To simplify this logic, we introduced new global value
-	  heap_pages_freeable_pages it means extra pages count we can free.
-	  gc_sweep_step() checks this value and moves empty pages to tomb_heap
-	  not more than this value.
-
-	  Because of this fix, heap_pages_swept_slots is no longer needed.
-
-	* gc.c (rb_objspace_t::heap_pages): restruct the objspace global
-	  status.
-
-	  remove the following fields
-	    * swept_slots (and heap_pages_swept_slots)
-	    * min_free_slots (and heap_pages_min_free_slots)
-	    * max_free_slots (and heap_pages_max_free_slots)
-	  And add the following filed.
-	    * freeable_pages (and heap_pages_freeable_pages)
-
-	* gc.c (heap_pages_free_unused_pages): unlink tomb heap pages
-	  because tomb heap should have only freeable pages.
-
-	* gc.c (heap_extend_pages): add parameters for future extension.
-
-Thu Mar 31 16:43:02 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c: add GC parameters to configure the following values:
-	  * RUBY_GC_HEAP_FREE_SLOTS_MIN_RATIO:
-	    allocate additional pages when free slots is lower than
-	    the value (total_slots * (this ratio)).
-	  * RUBY_GC_HEAP_FREE_SLOTS_MAX_RATIO:
-	    allow to free pages when free slots is greater than
-	    the value (total_slots * (this ratio)).
-
-	  Before this change, these values are hard coded.
-
-	* gc.c (ruby_gc_params_t): ditto.
-
-	* gc.c (ruby_gc_set_params): ditto.
-
-Thu Mar 31 15:59:17 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c (gc_verify_heap_page): check the number of zombies.
-
-	* gc.c (gc_verify_heap_pages): check also tomb heap.
-
-Thu Mar 31 15:48:18 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c (gc_page_sweep): return free slots count.
-
-	* gc.c (gc_sweep_step): use returned free slots count.
-
-	* gc.c (gc_sweep_step): change variable name `next'
-	  to `next_sweep_page'.
-
-Thu Mar 31 11:33:49 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/date/date_core.c (d_lite_strftime, dt_lite_strftime): [DOC]
-	  fix indent not to be a big sole verbatim.
-
-Thu Mar 31 11:18:19 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/date/date_core.c (Init_date_core): [DOC] fix misplaced doc
-	  of DateTime.  [ruby-core:74729] [Bug #12233]
-
-Thu Mar 31 03:41:02 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* ext/nkf/nkf-utf8/nkf.c: Merge upstream 69f7e74dde.
-	  fix indent.
-
-Wed Mar 30 16:33:19 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* extension.rdoc, extension.ja.rdoc: [DOC] Fix some errors.
-	  Renamed files, wrong method names or argument types; the example
-	  GetDBM macro is now updated to the current version of the actual
-	  code.  patch by Marcus Stollsteimer in [ruby-core:74690].
-	  [Bug #12228]
-
-Wed Mar 30 09:46:01 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/open-uri.rb: Use `userinfo` for authenticated proxy.
-	  [fix GH-1148] Patch by @SokichiFujita
-	* test/open-uri/test_open-uri.rb: ditto.
-	  [fix GH-1309] Patch by @jdamick
-
-Wed Mar 30 01:56:06 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* ext/nkf/nkf-utf8/nkf.c: Merge upstream 4f3edf80a0.
-	  patched by Anton Sivakov [Bug #12201] [Bug #12202]
-
-Wed Mar 30 01:54:30 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* tool/redmine-backporter.rb: add given revision to current changesets
-	  on associating the revision to the related ticket.
-
-Wed Mar 30 01:53:17 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* tool/merger.rb: update revision.h before merge.
-
-Tue Mar 29 19:33:54 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* addr2line.c: define toupper for its use. fix r54391.
-
-Tue Mar 29 19:23:46 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* include/ruby/ruby.h (rb_isupper, rb_islower, rb_isalpha, rb_isdigit,
-	  rb_isalnum, rb_isxdigit, rb_isblank, rb_isspace, rb_isblank,
-	  rb_iscntrl, rb_isprint, rb_ispunct, rb_isgraph,
-	  rb_tolower, rb_toupper): use inline function to avoid function call.
-
-	* include/ruby/ruby.h (rb_isascii): use inline function to clarify
-	  the logic.
-
-Tue Mar 29 18:56:55 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* tool/redmine-backporter.rb (backport): show merger.rb's path.
-
-	* tool/redmine-backporter.rb (show): show current issue again if no
-	  ticket number is given.
-
-	* tool/redmine-backporter.rb (rel): show error message if current
-	  bugs.ruby-lang.org doesn't support the API.
-
-Tue Mar 29 18:54:34 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* tool/merger.rb: support to backport header as backport identifier.
-	  Now you can specify by 'merge revision(s) 49254: [Backport #10738]'.
-
-Tue Mar 29 16:53:44 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode/case-folding.rb, casefold.h: Tweaked handling of 6
-	  special cases in CaseUnfold_11_Table.
-
-	* enc/unicode.c: Adjustments for above.
-
-	* test/ruby/enc/test_case_mapping.rb: Tests for the above: Some tests in
-	  test_titlecase activated; test_greek added. A test in test_cherokee fixed.
-
-Tue Mar 29 13:31:00 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Cleaned up some comments.
-
-Tue Mar 29 13:24:56 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode/case-folding.rb, casefold.h: Removing data for idempotent
-	  titlecasing.
-
-	* enc/unicode.c: Adjust code to data removal.
-
-Tue Mar 29 12:45:18 2016  Laurent Arnoud  <laurent@spkdev.net>
-
-	* lib/webrick/httpresponse.rb: Move error_body to method. It allow to
-	  override the body more easily. [fix GH-1307]
-	* test/webrick/test_httpresponse.rb: ditto.
-
-Tue Mar 29 06:40:53 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* error.c (rb_compile_err_append): rb_thread_t::base_block is no
-	  longer used.
-
-	* iseq.c (rb_iseq_compile_with_option): ditto, no protection is
-	  needed.
-
-Tue Mar 29 06:39:22 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* parse.y (struct parser_params): move parse_in_eval flag from
-	  rb_thread_t.
-
-	* parse.y (rb_parser_set_context): set parsing context, not only
-	  mild error flag.
-
-	* iseq.c (rb_iseq_compile_with_option): the parser now refers no
-	  thread local states to be restored.
-
-	* vm_eval.c (eval_string_with_cref): ditto.
-
-Mon Mar 28 21:24:02 2016  Kazuhiro NISHIYAMA  <zn@mbf.nifty.com>
-
-	* numeric.c (int_pos_p): fix typos.
-
-Mon Mar 28 14:54:49 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Refactoring in preparation for data reduction for
-	  titlecase.
-
-Mon Mar 28 14:36:36 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Minor refactoring for I WITH DOT ABOVE.
-
-Mon Mar 28 14:26:24 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Removed code now covered by data from table.
-
-Mon Mar 28 11:49:21 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Adding comments. [ci skip]
-
-Mon Mar 28 11:30:23 2016  Shinichi Maeshima  <netwillnet@gmail.com>
-
-	* lib/rubygems.rb: Fix `Gem.find_spec_for_exe` picks oldest gem.
-	  https://github.com/travis-ci/travis-ci/issues/5798
-	  https://github.com/rubygems/rubygems/pull/1566
-	* test/rubygems/test_gem.rb: ditto.
-
-Mon Mar 28 11:26:31 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/rubygems.rb, lib/rubygems/*, test/rubygems/*: Update rubygems-2.6.2.
-	  Please see entries of 2.6.2 on
-	  https://github.com/rubygems/rubygems/blob/master/History.txt
-
-Mon Mar 28 11:02:31 2016  Hiroshi Shirosaki  <h.shirosaki@gmail.com>
-
-	* lib/rubygems/test_case.rb: Fix test on Windows for inconsistent temp path.
-	  https://github.com/rubygems/rubygems/pull/1554
-	  [Bug #12193][ruby-core:74431]
-
-Mon Mar 28 08:19:49 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* sprintf.c (rb_str_format): refactor floating point format of
-	  Rational by using generic Integer functions.
-
-	* sprintf.c (rb_str_format): fix buffer overflow, length must be
-	  greater than precision.  reported by William Bowling <will AT
-	  wbowling.info>.
-
-Sun Mar 27 12:13:37 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* sprintf.c (rb_str_format): convert Rational to floating point
-	  format by using generic Integer functions, not by methods which
-	  can be overwritten.
-
-Sat Mar 26 10:55:12 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* numeric.c (rb_int2str): conversion function to String for
-	  generic Integer.
-
-	* numeric.c (rb_int_round): rounding function for generic
-	  Integers.
-
-	* numeric.c (rb_int_{uminus,plus,minus,mul,idiv,modulo}): basic
-	  arithmetic functions for generic Integers.
-
-	* numeric.c (FIXNUM_{POSITIVE,NEGATIVE,ZERO}_P): predict macros
-	  only for Fixnum.
-
-Sat Mar 26 06:34:24 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* localeinit.c (rb_locale_charmap_index): fix prototype.
-	  patched by Andreas Schwab [Bug #12218]
-
-Fri Mar 25 16:40:48 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_mapping.rb: Additional tests title case;
-	  some not yet activated.
-
-Fri Mar 25 13:38:11 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* ext/openssl/extconf.rb: check SSL_CTX_set_next_proto_select_cb
-	  function rather than OPENSSL_NPN_NEGOTIATED macro. it exists
-	  even if it is disabled by OpenSSL configuration.
-	  [ruby-core:74384] [Bug #12182]
-
-	* ext/openssl/ossl_ssl.c: update #ifdef(s) as above.
-
-	* test/openssl/test_ssl.rb: skip NPN tests if NPN is disabled.
-
-Fri Mar 25 11:08:37 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/uri/http.rb (URI::HTTP#initialize): [DOC] fix example,
-	  missing mandatory arguments.  [ruby-core:74540] [Bug #12215]
-
-Fri Mar 25 01:50:58 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* thread_pthread.c (reserve_stack): fix reserving position where
-	  the stack growing bottom to top. [Bug #12118]
-
-Fri Mar 25 01:10:42 2016  Sebastian Schuberth  <sschuberth@gmail.com>
-
-	* lib/mkmf.rb (find_executable0): On Windows, it is actually valid
-	  to surround individual PATH directory entries with double
-	  quotes. Remove these before joining the path as otherwise the
-	  literal quotes would become part of the path, resulting in the
-	  executable not to be found.  [Fix GH-1305]
-
-Thu Mar 24 22:38:18 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* strftime.c (FMT, FMTV): remove recursive-assignments to get rid
-	  of undefined behavior.  [ruby-core:74532] [Bug #12213]
-
-Thu Mar 24 17:44:02 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* strftime.c (FMT_PADDING): extract format for padding.
-
-	* strftime.c (FMT_PRECISION): extract precision formula.
-
-	* strftime.c (FMTV): append formatted string to expand the result.
-
-Thu Mar 24 14:20:21 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* strftime.c (STRFTIME): deal with case conversion flags for
-	  recursive formats.
-
-Thu Mar 24 12:43:26 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/date/date_core.c (dt_lite_iso8601): strftimev() always
-	  returns a String, so append them directly.
-
-	* ext/date/date_core.c (d_lite_jisx0301, iso8601_timediv),
-	  (dt_lite_jisx0301): format by the format string in local buffer
-	  to prevent intermediate strings from GC.
-
-	* ext/date/date_core.c (mk_inspect_raw, mk_inspect): inspect by
-	  "%+"PRIsVALUE, to prevent intermediate strings from GC.
-
-Thu Mar 24 11:43:32 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* strftime.c (rb_strftime_with_timespec): remove unnecessary
-	  check, as `s` equals to `endp` when recursed STRFTIME resized
-	  the capacity same as the size.
-
-Wed Mar 23 21:48:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* enum.c (ary_inject_op): put subtract operation out of if-clause.
-
-Wed Mar 23 21:38:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* enum.c (ary_inject_op): Use Kahan's compensated summation algorithm
-	  for summing up float values.
-
-Wed Mar 23 20:56:59 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* strftime.c (rb_strftime_with_timespec): append formatted results
-	  to the given string with expanding, and also deal with NUL chars.
-
-	* strftime.c (rb_strftime, rb_strftime_timespec): return formatted
-	  string, not the length put in the given buffer.
-
-	* time.c (rb_strftime_alloc): no longer needs to retry with
-	  reallocating buffers.
-
-	* time.c (time_strftime): no longer needs to split by NUL chars.
-
-Wed Mar 23 14:23:54 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* lib/rdoc/ri/driver.rb (interactive): rescue NotFoundError raised in
-	  expand_name. (display_name rescues NotFoundError by itself,
-	  the original logic looks buggy...)
-
-Wed Mar 23 11:44:53 2016  cremno  <cremno@mail.ru>
-
-	* marshal.c (r_long): cast to `signed char`, which is used
-	  already, instead of SIGN_EXTEND_CHAR.
-
-	* parse.y: SIGN_EXTEND_CHAR is no longer used.  [Fix GH-1302]
-
-Wed Mar 23 11:38:47 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* cygwin/GNUmakefile.in (MSYS2_ARG_CONV_EXCL_PARAM):
-	  * add missing parentheses and remove double quotes.
-	  * rename to get rid of recursive references.
-	  * as --excludes-dir option is for a path name, its argument
-	    should be converted.
-	  [ruby-dev:49526] [Bug #12199]
-
-Wed Mar 23 10:39:38 2016  Koichi ITO  <koic.ito@gmail.com>
-
-	* variable.c: Added documentation about order of `Module#constants`
-	  [ci skip][Bug #12121][ruby-dev:49505][fix GH-1301]
-
-Tue Mar 22 21:08:30 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* include/ruby/oniguruma.h: Additional flag for characters that are titlecase.
-
-	* enc/unicode/case-folding.rb, casefold.h: Using above flag in data.
-
-	* enc/unicode.c: Marking capitalized character as unmodified if it is
-	  already titlecase.
-
-	* test/ruby/enc/test_case_mapping.rb: Tests for above functionality.
-
-Tue Mar 22 14:18:59 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* parse.y (lambda_body, parser_yylex): warn mismatched indentation
-	  of lambda block.
-
-Tue Mar 22 11:36:49 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* time.c (wmul): wrong condition.
-	  fixed many test failures on 32bit and LLP64 platforms.
-
-Tue Mar 22 10:31:34 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* time.c (wdiv, wmod): wdivmod0() assumes the 3rd and the 4th arguments
-	  are valid pointers.
-	  maybe checking them in wdivmod0() is better manner, but I guess that
-	  passing real dummy pointers may be faster than checking and branching
-	  in wdivmod0().
-	  this commit fixes SEGV on 32bit and LLP64 platforms.
-
-Tue Mar 22 10:24:04 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* time.c (divmodv): void function never returns any value.
-
-Tue Mar 22 10:11:01 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* test/lib/test/unit.rb (Test::Unit::StatusLine#failed): print
-	  failed messages only if replacing mode, otherwise defer them
-	  until the end, to get rid of interleaving failures with progress
-	  messages.  refix r54195.
-
-Tue Mar 22 03:45:03 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* time.c (MUL_OVERFLOW_FIXWV_P): defined for FIXWV.
-
-	* time.c (wmul): use MUL_OVERFLOW_FIXWV_P and only switch.
-
-	* time.c (wmul): use mul which has Fixnum optimization.
-
-	* time.c (rb_time_magnify): If WIDEVALUE_IS_WIDER, wmul() has the same
-	  optimized logic, else mul() has also the similar logic for Fixnum.
-
-	* time.c (rb_time_unmagnify): almost ditto.
-
-Tue Mar 22 03:10:09 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* time.c (divmodv): add the case both arguments are Fixnum.
-
-	* time.c (wquo): use quo which has Fixnum optimization.
-
-	* time.c (wdivmod0): added for WIDEVALUE_IS_WIDER.
-
-	* time.c (wdivmod): use wdivmod0 and divmodv.
-	  divmodv has Fixnum optimization.
-
-	* time.c (wdiv): use wdivmod0 and div to avoid the use of divmodv which
-	  calls id_quo whose return value is array.
-
-	* time.c (wmod): use wdivmod0 and mod to avoid the use of divmodv which
-	  calls id_quo whose return value is array.
-
-Mon Mar 21 22:32:50 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* internal.h (rb_fix_divmod_fix): like r54213, use FIX2NUM only if
-	  x == FIXNUM_MIN && y == -1. This must be a rare case and it is
-	  expected compiler to handle well.
-
-Mon Mar 21 22:15:11 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* time.c (mod): Add Fixnum case.
-
-	* time.c (quo): c can be Fixnum except a == FIXNUM_MIN && b == -1.
-	  Such case can be optimized out because quo()'s argument is constant.
-
-Mon Mar 21 22:09:24 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* internal.h (rb_fix_mul_fix): multiply converted values, not
-	  object VALUEs.
-
-Mon Mar 21 20:18:29 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* common.mk (TEST_EXCLUDES, EXCLUDE_TESTFRAMEWORK): use full spell
-	  long option.
-
-	* cygwin/GNUmakefile.in (MSYS2_ARG_CONV_EXCL): suppress path name
-	  conversions by msys2.  [ruby-dev:49525] [Bug #12199]
-
-Mon Mar 21 19:09:31 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* string.c (enc_succ_alnum_char): try to skip an invalid character
-	  gap between GREEK CAPITAL RHO and SIGMA.
-	  [ruby-core:74478] [Bug #12204]
-
-Mon Mar 21 18:55:49 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* node.c (rb_gc_mark_node): NODE_MATCH2 can have nd_args, u3,
-	  since r54100.
-
-Sun Mar 20 21:17:13 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* internal.h (rb_int128t2big): declare only when HAVE_INT128_T.
-	  fixed a compile error with VC++ introduced at r54203.
-
-Sun Mar 20 20:10:14 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* internal.h (DLONG): defined if long is 32bit (and LONG_LONG is 64bit;
-	  but LONG_LONG is always defined as 64bit), or there's int128_t.
-
-	* internal.h (DL2NUM): defined if DLONG is defined.
-
-	* internal.h (rb_fix_mul_fix): defined for `Fixnum * Fixnum`.
-
-	* insns.def (opt_mul): use rb_fix_mul_fix().
-
-	* numeric.c (fix_mul): ditto.
-
-	* time.c (mul): ditto.
-
-Sun Mar 20 18:53:49 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* numeric.c (fix_gt, fix_ge, fix_lt, fix_le): optimize comparisons
-	  Fixnum against Bignum by rb_big_cmp in inversed order without
-	  new Bignum instance.
-
-Sun Mar 20 18:44:52 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* time.c (add): remove FIXABLE() which is in LONG2NUM().
-
-	* time.c (sub): ditto.
-
-	* time.c (mul): ditto.
-
-Sun Mar 20 04:46:02 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* bignum.c (rb_big_cmp): reduce the code.
-
-	* bignum.c (rb_big_eq): If normalized bignum is still bignum,
-	  it must be larger than fixnum.
-
-Sat Mar 20 00:58:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* include/ruby/intern.h (rb_big_odd_p, rb_big_even_p): move to
-	  internal.h so that they are exported only for ruby itself.
-
-	* internal.h (rb_big_odd_p, rb_big_even_p): ditto.
-
-Sat Mar 19 21:56:23 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* test/lib/test/unit.rb (Test::Unit::StatusLine#failed): defer
-	  failed messages until the end in verbose mode, to get rid of
-	  interleaving failures with progress messages.
-
-Sat Mar 19 21:53:35 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* numeric.c (fix_cmp): invert the result as the comparison is
-	  inverted.
-
-Sat Mar 19 18:32:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* numeric.c (int_to_f): raise NotImplementedError when a receiver
-	  class is unknown.
-
-	* test/-ext-/integer/test_my_integer.rb (test_my_integer_to_f): modify
-	  a test for the above change.
-
-Sat Mar 19 18:21:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* bignum.c (Bignum#<=>): remove it because they are unified with
-	  Integer#<=>.
-
-	* numeric.c (Integer#<=>, Fixnum#<=>): move <=> method from Fixnum to
-	  Integer.
-
-	* numeric.c (int_cmp): add this method for Integer#<=>.
-
-	* test/-ext-/integer/test_my_integer.rb (test_my_integer_cmp): add a
-	  test to examine Integer#<=> for unknown subclasses.
-
-Sat Mar 19 14:46:18 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* iseq.c (rb_iseq_compile_with_option): make the parser in mild
-	  error.
-
-	* load.c (rb_load_internal0): ditto.
-
-	* parse.y (yycompile0): return the error message within the error
-	  to be raised.  [Feature #11951]
-
-	* parse.y (parser_compile_error): accumulate error messages in the
-	  error_buffer.
-
-Sat Mar 19 03:57:13 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* time.c (LOCALTIME): organize #ifdefs.
-
-	* time.c (GMTIME): define only ifndef HAVE_STRUCT_TM_TM_GMTOFF.
-
-Sat Mar 19 03:53:31 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* configure.in (rb_cv_member_struct_tm_tm_gmtoff): For Linux (glibc)
-	  define _BSD_SOURCE for time.h to define struct tm.tm_gmtoff.
-
-	* time.c: define _BSD_SOURCE at the top.
-
-Sat Mar 19 03:00:50 2016  Rei Odaira  <Rei.Odaira@gmail.com>
-
-	* test/-ext-/time/test_new.rb (test_timespec_new): change a gmtoff
-	  test to a better one that does not depend on whether the current
-	  time is in summer time or not.
-
-Fri Mar 19 00:00:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* bignum.c (rb_big_to_f, Bignum#to_f): removed them because they are
-	  unified with int_to_f and Integer#to_f.
-
-	* numeric.c (int_to_f): treat Bignum values directly.
-
-Fri Mar 18 23:41:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* numeric.c (int_to_f, fix_to_f): rename fix_to_f to int_to_f, and add
-	  treatment for subclasses which don't have definitions of to_f method.
-
-	* numeric.c (Integer#to_f, Fixnum#to_f): move to_f method from Fixnum
-	  to Integer.
-
-	* ext/-test-/integer/my_integer.c: define helper class for testing
-	  to_f method for a subclass of Integer.
-
-	* ext/-test-/integer/extconf.rb: ditto.
-
-	* ext/-test-/integer/init.c: ditto.
-
-	* test/-ext-/integer/test_my_integer.rb: examine to_f method for a
-	  subclass of Integer.
-
-Fri Mar 18 22:32:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* include/ruby/intern.h (rb_big_hash): Move to internal.h.
-
-	* internal.h: ditto.
-
-Fri Mar 18 22:10:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* bignum.c (Bignum#eql?): remove its definition because it is unified
-	  with Numeric#eql?.
-
-	* numeric.c (num_eql): treat Bignum values directly.
-
-Fri Mar 18 21:57:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* bignum.c (rb_big_to_s, Bignum#to_s): remove its definition because
-	  it is unified with Integer#to_s.
-
-	* numeric.c (int_to_s): treat Bignum values directly.
-
-Fri Mar 18 21:30:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* numeric.c (int_to_s): Move from fix_to_s.
-
-	* numeric.c (Integer#to_s): Move from Fixnum#to_s.
-
-Fri Mar 18 16:22:24 2016  Victor Nawothnig  <Victor.Nawothnig@gmail.com>
-
-	* parse.y (parse_numvar): NTH_REF must be less than a half of
-	  INT_MAX, as it is left-shifted to be ORed with back-ref flag.
-	  [ruby-core:74444] [Bug#12192] [Fix GH-1296]
-
-Fri Mar 18 12:25:30 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* gc.c (tick): fix missing close parenthesis.  [Fix GH-1291]
-
-Fri Mar 18 10:24:12 2016  Naotoshi Seo  <sonots@gmail.com>
-
-	* ext/date/date_core.c (datetime_to_time): preserve timezone info
-	  [Bug #12189] [Fix GH-1295]
-
-Fri Mar 18 10:17:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* bignum.c (rb_big_hash): make it public function to be available in
-	  other source files, and remove documentation comment for Bignum#hash.
-
-	* bignum.c (Bignum#hash): remove its definition because it is unified
-	  with Object#hash.
-
-	* include/ruby/intern.h (rb_big_hash): add a prototype declaration.
-
-	* hash.c (any_hash): treat Bignum values directly.
-
-Fri Mar 18 02:35:12 2016  Naotoshi Seo  <sonots@gmail.com>
-
-	* lib/time.rb (parse, strptime): Fix Time.parse/strptime does not
-	  have compatibility with DateTime.parse/strptime in terms of parsing
-	  timezone [Bug #12190] [Fix GH-1297]
-
-Fri Mar 18 02:17:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* numeric.c (fix_zero_p, fix_even_p, fix_odd_p): remove needless
-	  functions.
-
-Fri Mar 18 02:15:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* numeric.c (int_even_p): treat Fixnum and Bignum values directly.
-
-Fri Mar 18 02:07:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* bignum.c (Bignum#even?, Bignum#odd?): remove definitions
-	  because they are unified with Integer#even? and Integer#odd?.
-
-	* numeric.c (Fixnum#zero?, Fixnum#even?, Fixnum#odd?): remove
-	  definitions because they are unified with Numeric#zero?,
-	  Integer#even?, and Integer#odd?.
-
-	* numeric.c (num_zero_p, int_odd_p): treat Fixnum and
-	  Bignum values directly.
-
-	* test/ruby/test_integer.rb (test_odd_p_even_p): remove meaningless
-	  test case.
-
-Fri Mar 18 01:51:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* bignum.c (rb_big_even_p, rb_big_odd_p): make them public functions
-	  to be available in other source files.
-
-	* include/ruby/intern.h (rb_big_even_p, rb_big_odd_p): add prototype
-	  declarations.
-
-Fri Mar 18 00:25:56 2016  Tanaka Akira  <akr@fsij.org>
-
-	* enum.c (ary_inject_op): Implement the specialized code for sum of
-	  float numbers.
-
-Fri Mar 18 00:15:05 2016  Yusuke Endoh  <mame@ruby-lang.org>
-
-	* numeric.c (num_step): use rb_equal for zero check. rb_num_coerce_cmp
-	  created an object which caused extra overhead.
-
-Thu Mar 17 22:21:34 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/ruby.h (RB_GC_GUARD_PTR): remove intermediate
-	  macro, and expand for each RB_GC_GUARD.  [Fix GH-1293]
-
-Thu Mar 17 22:08:33 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* compile.c (iseq_specialized_instruction): move specialization
-	  for opt_newarray_max/min from translation phase.
-
-Thu Mar 17 21:52:09 2016  Yusuke Endoh  <mame@ruby-lang.org>
-
-	* array.c, enum.c: make rdoc format consistent.
-
-Thu Mar 17 21:47:57 2016  Yusuke Endoh  <mame@ruby-lang.org>
-
-	* NEWS: add Array#max, #min, and the optimization.  [Feature #12172]
-
-Thu Mar 17 21:45:02 2016  Yusuke Endoh  <mame@ruby-lang.org>
-
-	* compile.c (NODE_CALL): add optimization shortcut for Array#max/min.
-	  Now `[x, y].max` is optimized so that a temporal array object is not
-	  created in some condition.  [Feature #12172]
-
-	* insns.def (opt_newarray_max, opt_newarray_min): added.
-
-Thu Mar 17 21:35:52 2016  Yusuke Endoh  <mame@ruby-lang.org>
-
-	* array.c (rb_ary_max, rb_ary_min): implement Array#max and min with
-	  arguments.  replace super call with rb_nmin_run.
-
-	* enum.c (nmin_run): exported (as rb_nmin_run).
-
-	* internal.h: added a prototype for rb_nmin_run.
-
-Thu Mar 17 21:24:52 2016  Yusuke Endoh  <mame@ruby-lang.org>
-
-	* array.c (rb_ary_max, rb_ary_min): implement a block by itself instead
-	  of delegating Enumerable#max/min.
-
-Thu Mar 17 21:09:34 2016  Yusuke Endoh  <mame@ruby-lang.org>
-
-	* array.c (rb_ary_max, rb_ary_min): Array#max and Array#min added.
-	  [Feature #12172]
-
-	* internal.h (OPTIMIZED_CMP): moved from enum.c so that array.c can
-	  use it.
-
-	* test/ruby/test_array.rb (test_max, test_min): tests for Array#max
-	  and Array#min.
-
-	* test/ruby/test_enum.rb (test_max, test_min): revised a bit to test
-	  Enumerable#max and #min explicitly.
-
-Thu Mar 17 21:02:42 2016  Yusuke Endoh  <mame@ruby-lang.org>
-
-	* internal.c: struct cmp_opt_data added for refactoring out a data
-	  structure for CMP_OPTIMIZABLE
-
-	* array.c (struct ary_sort_data): use struct cmp_opt_data.
-
-	* enum.c (struct min_t, max_t, min_max_t): use struct cmp_opt_data.
-
-Thu Mar 17 20:55:21 2016  Tanaka Akira  <akr@fsij.org>
-
-	* enum.c (ary_inject_op): Extracted from enum_inject.
-
-Thu Mar 17 18:39:04 2016  Tanaka Akira  <akr@fsij.org>
-
-	* enum.c (enum_inject): Implement the specialized code for sum of
-	  integers including Bignums.
-
-	* internal.h (rb_fix_plus): Declared to be usable from enum_inject.
-
-	* numeric.c (rb_fix_plus): Defined.
-
-Thu Mar 17 17:20:28 2016  Anton Davydov  <antondavydov.o@gmail.com>
-
-	* thread_sync.c: [DOC] Update documentation for Queue class
-	  description.  [Fix GH-1292]
-
-Thu Mar 17 17:14:51 2016  Dinar Valeev  <dvaleev@suse.com>
-
-	* gc.c (tick): Use __builtin_ppc_get_timebase for POWER arch.
-	  [Fix GH-1291]
-
-Thu Mar 17 11:51:48 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* lib/securerandom.rb (gen_random): to avoid blocking on Windows.
-	  On Windows OpenSSL RAND_bytes (underlying implementation is
-	  RAND_poll in crypto/rand/rand_win.c) may be blocked at
-	  NetStatisticsGet.
-	  https://wiki.openssl.org/index.php/Random_Numbers#Windows_Issues
-	  Instead of this, use Random.raw_seed directly (whose implementation
-	  CryptGenRandom is one of the source of
-	  entropy of RAND_poll on Windows).
-	  https://wiki.openssl.org/index.php/Random_Numbers
-	  Note: CryptGenRandom function is PRNG and doesn't check its entropy,
-	  so it won't block. [Bug #12139]
-	  https://msdn.microsoft.com/ja-jp/library/windows/desktop/aa379942.aspx
-	  https://tools.ietf.org/html/rfc4086#section-7.1.3
-	  https://eprint.iacr.org/2007/419.pdf
-	  http://www.cs.huji.ac.il/~dolev/pubs/thesis/msc-thesis-leo.pdf
-
-Thu Mar 17 12:09:00 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Fixed two macro definitions.
-	* test/ruby/enc/test_case_mapping.rb: Test cases that detected
-	  the above bugs.
-
-Thu Mar 17 11:36:27 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/socket/option.c (inspect_tcpi_msec): more accurate condition
-	  for TCPI msec member inspection function.
-	  [ruby-core:74388] [Bug #12185]
-
-Thu Mar 17 08:13:43 2016  Rei Odaira  <Rei.Odaira@gmail.com>
-
-	* test/-ext-/time/test_new.rb (test_timespec_new): Time#gmtoff values
-	  are the same only when both or neither of the Time objects are in
-	  summer time (daylight-saving time).
-
-Thu Mar 17 07:17:36 2016  Eric Hodel  <drbrain@segment7.net>
-
-	* marshal.c (r_object0):  raise ArgumentError when linking to undefined
-	  object.
-
-Thu Mar 17 00:45:00 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* test/ruby/test_bignum.rb: Make sure to use Bignum values in the tests.
-
-Wed Mar 16 23:10:25 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* defs/keywords (alias, undef): symbol literals are allowed.
-
-	* parse.y (parse_percent): should parse symbol literals for alias
-	  and undef.  [ruby-dev:47681] [Bug #8851]
-
-Wed Mar 16 21:39:39 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* enc/trans/JIS: update Unicode's notice. [Bug #11844]
-
-Wed Mar 16 20:03:35 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* proc.c (proc_binding): proc from symbol can not make a binding.
-	  [ruby-core:74100] [Bug #12137]
-
-Wed Mar 16 18:42:45 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_mapping.rb: Fixed and activated a test for Cherokee.
-
-Wed Mar 16 17:58:56 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_mapping.rb: Fixed a logical error.
-
-Wed Mar 16 17:57:34 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_mapping.rb: Adding tests for Cherokee.
-	  One test not yet working.
-	  (with Kimihito Matsui)
-
-Wed Mar 16 15:44:05 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_mapping.rb: Adding tests for actual Unicode
-	  case mapping. Fixing some aliasing issues.
-	  (with Kimihito Matsui)
-
-Tue Mar 15 21:38:28 2016  Tanaka Akira  <akr@fsij.org>
-
-	* enum.c (enum_inject): Consider redefinition of Fixnum#+.
-	  [ruby-dev:49510] [Bug#12178] Reported by usa.
-
-Tue Mar 15 20:32:57 2016  Tanaka Akira  <akr@fsij.org>
-
-	* enum.c (enum_inject): Implement the specialized code for :+ operator
-	  for Fixnums.
-
-Tue Mar 15 20:21:01 2016  Tanaka Akira  <akr@fsij.org>
-
-	* enum.c (enum_inject): Implement the specialized code for self is an
-	  array and a symbol operator is given.
-
-Tue Mar 15 16:29:51 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Eliminating common code.
-	  (with Kimihito Matsui)
-
-Tue Mar 15 16:17:09 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Expansion of some code repetition in preparation for
-	  elimination of common code pieces.
-	  (with Kimihito Matsui)
-
-Tue Mar 15 13:49:23 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Additional macros and code to use mapping data in
-	  CaseMappingSpecials array.
-	  (with Kimihito Matsui)
-
-Tue Mar 15 13:41:22 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* internal.h (rb_gc_mark_global_tbl): should be private,
-	  but was accidentally exported.
-
-Tue Mar 15 12:51:06 2016  Marcus Stollsteimer  <sto.mar@web.de>
-
-	* doc/extension.ja.rdoc: Fix RDoc markup in doc/extension*.rdoc.
-	  [ci skip][Bug #12143][ruby-core:74143]
-	* doc/extension.rdoc: ditto.
-
-Tue Mar 15 09:56:41 2016  Ian Lunderskov  <ian.lunderskov@gmail.com>
-
-	* time.c: Minor typo in Time#dst? documentation.
-	  [ci skip][fix GH-1290]
-
-Tue Mar 15 04:36:41 2016  Charles Oliver Nutter  <headius@headius.com>
-
-	* test/ruby/test_rubyoptions.rb (test_disable): add tests for
-	  --disable-gems and --disable-did_you_mean.
-
-Tue Mar 15 03:35:04 2016  Eric Hodel  <drbrain@segment7.net>
-
-	* marshal.c (r_object0): Fix Marshal crash for corrupt extended object.
-
-Tue Mar 15 01:22:27 2016  Charles Oliver Nutter  <headius@headius.com>
-
-	* test/ruby/test_rubyoptions.rb: make version matching support
-	  JRuby's version output.
-
-Mon Mar 14 19:05:39 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* bignum.c (big2str_2bdigits): reduce div instruction.
-
-Mon Mar 14 18:39:53 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* include/ruby/oniguruma.h, enc/unicode.c: Adjusting flag assignments
-	  and macros to work with unified CaseMappingSpecials array.
-	  (with Kimihito Matsui)
-
-Mon Mar 14 16:53:37 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* compile.c (compile_named_capture_assign): optimize named capture
-	  assignments, by replacing repeating global variable accesses
-	  with `dup`, and by returning the matched result instead of
-	  re-getting it from the MatchData.
-
-	* parse.y (reg_named_capture_assign_gen): build just assignment
-	  nodes for the optimization.
-
-Mon Mar 14 16:02:59 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* file.c (ruby_is_fd_loadable): now return -1 if loadable but
-	  may block.
-
-	* ruby.c (open_load_file): wait to read by the result of
-	  ruby_is_fd_loadable, without fstat.
-
-Mon Mar 14 13:38:38 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* numeric.c (fix2str): improve r54092 like rb_int2big().
-
-Mon Mar 14 10:02:23 2016  Eric Wong  <e@80x24.org>
-
-	* ext/openssl/ossl_ssl.c (ossl_sslctx_setup): document as MT-unsafe
-	  [ruby-core:73803] [Bug #12069]
-
-Sun Mar 13 09:43:23 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/win32.h (O_SHARE_DELETE): change to fit Fixnum
-	  limit.  [ruby-core:74285] [Bug #12171]
-
-Sun Mar 13 09:15:45 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* numeric.c (rb_fix2str): fix edge case, accidentally generated
-	  wrong Fixnum from LONG_MIN.
-
-Sat Mar 12 09:50:27 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* vm_eval.c (rb_f_catch): [DOC] fix malformed RDoc syntax, "+...+"
-	  cannot enclose non-identifier characters.
-	  a patch by Sebastian S in [ruby-core:74278].  [Bug#12170]
-
-Sat Mar 12 02:44:48 2016  Tanaka Akira  <akr@fsij.org>
-
-	* test/lib/test/unit.rb: describe !/REGEXP/ in the help message.
-
-Fri Mar 11 17:03:09 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* test/lib/test/unit.rb (Options#non_options): make regexp name
-	  options prefixed with "!" negative filters.
-
-	* common.mk (TEST_EXCLUDES): use negative filter to exclude memory
-	  leak tests.  -x option excludes test files, not test methods.
-
-Fri Mar 11 16:11:27 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode/case-folding.rb, casefold.h: Streamlining approach to
-	  case mapping data not available from case folding by unifying all
-	  three cases (special title, special upper, special lower).
-	* enc/unicode.c: Adjust macro names for above (macros are currently inactive).
-	  (with Kimihito Matsui)
-
-Thu Mar 10 17:34:16 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* iseq.c (prepare_iseq_build): enable coverage by coverage_enabled
-	  option, not by parse_in_eval flag in the thread context.
-
-	* iseq.h (rb_compile_option_struct): add coverage_enabled flag.
-
-	* parse.y (yycompile0): set coverage_enabled flag if coverage
-	  array is made.
-
-Thu Mar 10 15:19:54 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* node.c (dump_option): nd_compile_option is a hidden hash object,
-	  cannot call inspect on it.
-
-Thu Mar 10 09:49:54 2016  Rei Odaira  <Rei.Odaira@gmail.com>
-
-	* test/socket/test_socket.rb (test_udp_recvmsg_truncation):
-	  AIX does not set the MSG_TRUNC flag for a message partially read
-	  by recvmsg(2) with the MSG_PEEK flag set.
-
-Wed Mar  9 16:48:45 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* benchmark/driver.rb: fix my last commit (syntax error).
-
-Wed Mar  9 16:41:44 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* benchmark/driver.rb: fix output messages.
-
-	* benchmark/memory_wrapper.rb: use respond_to? because
-	  member? does not work well.
-
-Wed Mar  9 16:20:25 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* benchmark/driver.rb: support memory usage benchmark.
-	  use `--measure-target=[target]'.
-	  Now, we can use the following targets:
-	    * real (default): real time which returns process time in sec.
-	    * peak: peak memory usage (physical memory) in bytes.
-	    * size: last memory usage (physical memory) in bytes.
-
-	* benchmark/memory_wrapper.rb: ditto.
-
-Wed Mar  9 15:04:22 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* benchmark/bm_vm3_gc_old_full.rb: add GC.start benchmark.
-
-	* benchmark/bm_vm3_gc_old_immediate.rb: ditto.
-
-	* benchmark/bm_vm3_gc_old_lazy.rb: ditto.
-
-Wed Mar  9 14:59:11 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* benchmark/driver.rb: exit benchmarking if a benchmark process
-	  receives signals.
-
-Wed Mar  9 13:22:49 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* test/lib/memory_status.rb: make Memory::Status independent of
-	  MiniTest::Skip.
-
-	* test/lib/test/unit/assertions.rb (assert_no_memory_leak): skip
-	  if Memory::Status is not available.
-
-Wed Mar  9 09:19:55 2016  Rei Odaira  <Rei.Odaira@gmail.com>
-
-	* test/io/wait/test_io_wait.rb (test_wait_readwrite_timeout):
-	  select(2) in AIX returns "readable" for the write-side fd
-	  of a pipe, so it is not possible to use a pipe to test
-	  the read-write timeout of IO#wait on AIX.
-
-Wed Mar  9 03:35:22 2016  Charles Oliver Nutter  <headius@headius.com>
-
-	* test/ruby/test_require.rb (test_require_with_loaded_features_pop):
-	  Only remove PATH so threads don't accidentally double-pop.
-
-Wed Mar  9 00:29:46 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* vm_method.c (rb_alias): the original name should be properly
-	  available method_added method, set the name before calling the
-	  hook.
-
-Wed Mar  9 00:07:03 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/logger.rb (Logger::LogDevice#initialize): define using
-	  keyword arguments.
-
-Tue Mar  8 23:37:07 2016  Charles Oliver Nutter  <headius@headius.com>
-
-	* test/ruby/test_array.rb: split out the test for no stack error
-	  on large input for test_permutation, test_repeated_permutation,
-	  and test_repeated_combination, and make them all timeout:30.
-
-Tue Mar  8 17:20:21 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* intern.h (rb_divmod): assume compilers `/` and `%` comply C99
-	  and reduce branching. If a compiler doesn't comply, add #ifdefs.
-
-	* intern.h (rb_div): added for Ruby's behavior.
-
-	* intern.h (rb_mod): added for Ruby's behavior.
-
-	* insns.def (opt_div): use rb_div.
-
-	* insns.def (opt_mod): use rb_mod.
-
-	* numeric.c (fixdivmod): removed.
-
-	* numeric.c (fix_divide): use rb_div.
-
-	* numeric.c (fix_mod): use rb_mod.
-
-	* numeric.c (fix_divmod): use rb_divmod.
-
-Tue Mar  8 17:53:09 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* insns.def (opt_mod): show its method name on ZeroDivisionError.
-	  [Bug #12158]
-
-Tue Mar  8 17:33:38 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* win32/win32.c (rb_w32_write_console): now no need to check
-	  ERROR_CALL_NOT_IMPLEMENTED because it is for old Win9X.
-
-Tue Mar  8 16:54:29 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* win32/win32.c (rb_w32_write_console): stop the VT100 emulation if the
-	  console supports it natively.
-
-Tue Mar  8 08:13:01 2016  Rei Odaira  <Rei.Odaira@gmail.com>
-
-	* test/net/imap/test_imap.rb (test_idle_timeout): Because of the
-	  timeout specified in "imap.idle(0.2)", there is no guarantee that
-	  the server thread has done all the work before the client thread
-	  performs the assertions. It depends on the thread scheduling.
-	  Add checks to avoid false positives (on AIX, particularly).
-
-Tue Mar  8 00:42:22 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* ruby.c (warn_cr_in_shebang): meaningless check on DOSISH platforms.
-	  fixed a test failure introduced at r53998.
-
-Tue Mar  8 00:27:53 2016  CHIKANAGA Tomoyuki  <nagachika@ruby-lang.org>
-
-	* ext/tk/lib/tkextlib/tcllib/tablelist_tile.rb: fix method name typo.
-	  [ruby-core:72513] [Bug #11893] The patch provided by Akira Matsuda.
-
-
-Tue Mar  8 00:25:08 2016  CHIKANAGA Tomoyuki  <nagachika@ruby-lang.org>
-
-	* ext/tk/lib/tkextlib/tcllib/toolbar.rb: fix method name typo.
-	  [ruby-core:72511] [Bug #11891] The patch provided by Akira Matsuda.
-
-
-Tue Mar  8 00:21:58 2016  CHIKANAGA Tomoyuki  <nagachika@ruby-lang.org>
-
-	* ext/tk/lib/tkextlib/blt/tree.rb: fix method name typo.
-	  [ruby-core:72510] [Bug #11890] The patch provided by Akira Matsuda.
-
-
-Tue Mar  8 00:11:47 2016  CHIKANAGA Tomoyuki  <nagachika@ruby-lang.org>
-
-	* ext/tk/lib/tk/menubar.rb: fix a typo in font name. [ruby-core:72505]
-	  [Bug #11886] The patch provided by Akira Matsuda.
-
-	* ext/tk/sample/*.rb: ditto.
-
-Mon Mar  7 13:32:58 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* class.c (rb_define_class, rb_define_class_id_under): raise
-	  ArgumentError if super is 0, deprecated behavior which has been
-	  warned long time.
-
-Mon Mar  7 13:28:30 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* internal.h: move function declarations for class internals from
-	  include/ruby/intern.h.
-
-Mon Mar  7 10:58:07 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/win32ole/win32ole_event.c (rescue_callback): use
-	  rb_write_error_str instead of rb_write_error, to respect
-	  the encoding and prevent the message from GC.
-
-	* internal.h (rb_write_error_str): export.
-
-Mon Mar  7 01:38:41 2016  Rei Odaira  <Rei.Odaira@gmail.com>
-
-	* test/ruby/test_process.rb (test_execopts_gid): Skip a test
-	  that is known to fail on AIX. AIX allows setgid to
-	  a supplementary group, but Ruby does not allow the "-e"
-	  option when setgid'ed, so the test does not work as intended.
-
-Sun Mar  6 22:43:41 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* io.c (rb_obj_display): [DOC] fix output of Array, as Array#to_s
-	  is same as Array#inspect since 1.9.
-
-Sat Mar  5 09:50:58 2016  Rei Odaira  <Rei.Odaira@gmail.com>
-
-	* test/socket/test_addrinfo.rb (test_ipv6_address_predicates):
-	  IN6_IS_ADDR_V4COMPAT and IN6_IS_ADDR_V4MAPPED are broken
-	  on AIX, so skip related tests.
-
-Sat Mar  5 09:17:54 2016  Rei Odaira  <Rei.Odaira@gmail.com>
-
-	* test/rinda/test_rinda.rb (test_make_socket_ipv4_multicast):
-	  The fifth argument to getsockopt(2) should be modified to
-	  indicate the actual size of the value on return,
-	  but not in AIX. This is a know bug. Skip related tests.
-	* test/rinda/test_rinda.rb (test_ring_server_ipv4_multicast):
-	  ditto.
-	* test/rinda/test_rinda.rb (test_make_socket_unicast): ditto.
-	* test/socket/test_basicsocket.rb (test_getsockopt): ditto.
-	* test/socket/test_sockopt.rb (test_bool): ditto.
-
-Sat Mar  5 07:36:27 2016  Rei Odaira  <Rei.Odaira@gmail.com>
-
-	* test/-ext-/float/test_nextafter.rb: In AIX,
-	  nextafter(+0.0,-0.0)=+0.0, and nextafter(-0.0,+0.0)=-0.0,
-	  but they should return -0.0 and +0.0, respectively. This is
-	  a known bug in nextafter(3) on AIX, so skip related tests.
-
-Sat Mar  5 07:14:10 2016  Rei Odaira  <Rei.Odaira@gmail.com>
-
-	* test/zlib/test_zlib.rb (test_adler32_combine, test_crc32_combine):
-	  Skip two tests on AIX because zconf.h in zlib does not correctly
-	  recognize _LARGE_FILES in AIX. The problem was already reported
-	  to zlib, and skip these tests until it is fixed.
-
-Sat Mar  5 03:07:40 2016  Rei Odaira  <Rei.Odaira@gmail.com>
-
-	* thread_pthread.c (getstack): __pi_stacksize returned by
-	  pthread_getthrds_np() is wrong on AIX. Use
-	  __pi_stackend - __pi_stackaddr instead.
-
-Fri Mar  4 19:19:42 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c: use 2 bits with unsigned int for rb_objspace::flags::mode
-	  because it always returns 0 to 2 (non-negative value).
-
-Fri Mar  4 18:42:08 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c: rename "enum gc_stat" to "enum gc_mode"
-	  because there is a same name (no related) function gc_stat().
-
-	  Also gc_stat_* are renamed to gc_mode_*,
-	  gc_stat_transition() to gc_mode_transition(),
-	  rb_objspace::flags::stat is renamed to rb_objspace::flags::mode.
-
-	  Change rb_objspace::flags::mode from 2 bits to 3 bits because VC++
-	  returns negative enum value with 2 bits.
-
-	* gc.c (gc_mode): add a macro to access rb_objspace::flags::mode
-	  with verification code (verification is enabled only on
-	  RGENGC_CHECK_MODE > 0).
-
-	* gc.c (gc_mode_set): same macro for setter.
-
-Fri Mar  4 09:28:18 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/rubygems.rb, lib/rubygems/*, test/rubygems/*: Update rubygems-2.6.1.
-	  Please see entries of 2.6.0 and 2.6.1 on
-	  https://github.com/rubygems/rubygems/blob/master/History.txt
-	  [fix GH-1270] Patch by @segiddins
-
-Thu Mar  3 14:09:00 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/ostruct.rb (modifiable?, new_ostruct_member!, table!):
-	  rename methods for internal use with suffixes and make private,
-	  [ruby-core:71069] [Bug #11587]
-
-Wed Mar  2 16:28:48 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* vm_eval.c (method_missing): call by found method entry and get
-	  rid of searching the same method entry twice.
-
-	* vm_eval.c (vm_call0_body): calling method_missing method is
-	  method_missing().
-
-Wed Mar  2 15:13:33 2016  herwinw  <herwin@quarantainenet.nl>
-
-	* lib/xmlrpc.rb: Removed broken parser named XMLScanStreamParser.
-	  It's not works with current Ruby version.
-	  [fix GH-1271][ruby-core:59588][Bug #9369]
-	* lib/xmlrpc/config.rb: ditto.
-	* lib/xmlrpc/parser.rb: ditto.
-
-Wed Mar  2 15:08:33 2016  herwinw  <herwin@quarantainenet.nl>
-
-	* lib/xmlrpc.rb: Removed broken parser named XMLTreeParser.
-	  Required gem of its parser didn't compile on newer Ruby versions.
-	  [fix GH-1271][ruby-core:59590][Bug #9370]
-	* lib/xmlrpc/config.rb: ditto.
-	* lib/xmlrpc/parser.rb: ditto.
-
-Tue Mar  1 11:25:48 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/fileutils.rb: use keyword arguments instead of option
-	  hashes.
-
-Mon Feb 29 16:50:20 2016  hanachin  <hanachin@gmail.com>
-
-	* array.c (rb_ary_push_m): [DOC] Remove trailing comma from
-	  Array#push example, as other Array examples doesn't put trailing
-	  comma.  [Fix GH-1279]
-
-Mon Feb 29 16:31:01 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* common.mk, tool/mkconfig.rb: set cross_compiling option from
-	  Makefile, but not from rbconfig.rb, which is just going to be
-	  created by this command.
-
-Sun Feb 28 23:13:49 2016  C.J. Collier  <cjcollier@linuxfoundation.org>
-
-	* configure.in: Add summary to end of configure output.
-	  [Fix GH-1275]
-
-Sun Feb 28 20:23:36 2016  Masatoshi SEKI  <m_seki@mva.biglobe.ne.jp>
-
-	* lib/drb/drb.rb (error_print): Add verbose failure messages and
-	  avoid infamous DRb::DRbConnError. [Feature #12101]
-
-Sun Feb 28 13:40:46 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* error.c (nometh_err_initialize): add private_call? parameter.
-
-	* error.c (nometh_err_private_call_p): add private_call? method,
-	  to tell if the exception raised in private form FCALL or VCALL.
-	  [Feature #12043]
-
-	* vm_eval.c (make_no_method_exception): append private_call?
-	  argument.
-
-	* vm_insnhelper.c (ci_missing_reason): copy FCALL flag.
-
-Sun Feb 28 10:19:47 2016  Ryan T. Hosford  <tad.hosford@gmail.com>
-
-	* array.c (rb_ary_and): clarify that set intersection returns the
-	  unique elements common to both arrays.
-
-	* array.c (rb_ary_or): clarify that union preserves the order from
-	  the given arrays.
-
-Sat Feb 27 17:05:29 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode/case-folding.rb, casefold.h: Reducing size of TitleCase
-	  table by eliminating duplicates.
-	  (with Kimihito Matsui)
-
-Fri Feb 26 14:40:48 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* numeric.c (num_step_scan_args): comparison String with Numeric
-	  should raise TypeError. it is an invalid type, but not a
-	  mismatch the number of arguments.  [ruby-core:62430] [Bug #9810]
-
-Fri Feb 26 14:39:39 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* doc/extension.rdoc, doc/extension.ja.rdoc: add editor local
-	  variables, with commenting out by :enddoc: directives which are
-	  just ignored unless code object mode.  [Bug #12111]
-
-Fri Feb 26 12:25:56 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* doc/extension.ja.rdoc: removed rendering error caused by editor specific
-	  configuration on http://docs.ruby-lang.org/en/trunk/extension_rdoc.html .
-	  [Bug #12111][ruby-core:73990]
-
-Fri Feb 26 11:21:41 2016  herwinw  <herwin@quarantainenet.nl>
-
-	* lib/xmlrpc.rb: Removed references to NQXML. It's obsoleted parser.
-	  [fix GH-1245][ruby-core:59593][Feature #9371]
-	* lib/xmlrpc/config.rb: ditto.
-	* lib/xmlrpc/parser.rb: ditto.
-
-Fri Feb 26 11:10:19 2016  Rick Salevsky  <rsalevsky@suse.com>
-
-	* lib/tmpdir.rb: Unify to coding-style for method definition.
-	  [fix GH-1252]
-
-Fri Feb 26 11:02:04 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* README.md: update markdown syntax for anchor tag.
-	  [fix GH-1265] Patch by @lukBarros
-
-Fri Feb 26 10:52:29 2016  Alex Boyd  <alex@opengroove.org>
-
-	* lib/irb.rb: avoid to needless truncation when using back_trace_limit option.
-	  [fix GH-1205][ruby-core:72773][Bug #11969]
-
-Fri Feb 26 08:11:58 2016  Aaron Patterson <tenderlove@ruby-lang.org>
-
-	* gem_prelude.rb: Reduce system calls by activating the `did_you_mean`
-	  gem before requiring the gem.  Activating the gem puts the gem on
-	  the load path, where simply requiring the file will search every gem
-	  that's installed until it can find a gem that contains the
-	  `did_you_mean` file.
-
-Thu Feb 25 19:04:13 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode/case-folding.rb: Adding possibility for debugging output
-	  for TitleCase table in casefold.h.
-	  (with Kimihito Matsui)
-
-Wed Feb 24 22:31:13 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* include/ruby/oniguruma.h: Rearranging flag assignments and making
-	  space for titlecase indices; adding additional macros to add or
-	  extract titlecase index; adding comments for better documentation.
-	* enc/unicode.c: Moving some macros to include/ruby/oniguruma.h;
-	  activating use of titlecase indices.
-	  (with Kimihito Matsui)
-
-Wed Feb 24 21:03:04 2016  Tanaka Akira  <akr@fsij.org>
-
-	* random.c (limited_rand): Add a specialized path for when the limit fits
-	  in 32 bit.
-
-Tue Feb 23 21:52:24 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode/case-folding.rb, casefold.h: Outputting actual titlecase
-	  data (new table, with indices from other tables).
-	* enc/unicode.c: Ignoring titlecase data indices for the moment.
-	  (with Kimihito Matsui)
-
-Tue Feb 23 15:21:14 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode/case-folding.rb, casefold.h: Reading casing data from
-	  SpecialCasing.txt.
-	  (with Kimihito Matsui)
-
-Mon Feb 22 18:33:55 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode/case-folding.rb, casefold.h: Adding flag for title-case,
-	  not yet operational.
-	  (with Kimihito Matsui)
-
-Mon Feb 22 18:17:03 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode/case-folding.rb, casefold.h: Fixed bug that avoided inclusion
-	  of compatibility characters in upper-/lower-case mappings.
-	  (with Kimihito Matsui)
-
-Sun Feb 21 13:57:18 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* cgi/escape/escape.c: Optimize CGI.unescape performance by C ext
-	  for ASCII-compatible encodings.  [Fix GH-1250]
-
-Sun Feb 21 13:56:57 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* cgi/escape/escape.c: Optimize CGI.unescapeHTML performance by C
-	  ext for ASCII-compatible encodings.  [Fix GH-1242]
-
-Sat Feb 20 15:38:16 2016  Eric Wong  <e@80x24.org>
-
-	* doc/extension.rdoc: update paths for defs/ directory
-
-Sat Feb 20 14:44:15 2016  Lucas Buchala  <lucasbuchala@gmail.com>
-
-	* vm_eval.c (rb_mod_module_eval): [DOC] Fix documentation
-	  signature for Module#module_eval.  [Fix GH-1258]
-
-Sat Feb 20 14:40:44 2016  Adam O'Connor  <northband@gmail.com>
-
-	* README.md: a few grammatical changes to the main Ruby README.md.
-	  [Fix GH-1259]
-
-Sat Feb 20 13:04:22 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* dir.c (push_pattern, push_glob): deal with read paths as UTF-8
-	  to stat later, on Windows as well as OS X.
-	  [ruby-core:73868] [Bug #12081]
-
-Sat Feb 20 01:53:33 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* object.c (rb_mod_const_get): make error message at uninterned
-	  string consistent with symbols.  [ruby-dev:49498] [Bug #12089]
-
-Fri Feb 19 23:37:52 2016  Masahiro Tomita  <tommy@tmtm.org>
-
-	* lib/find.rb (Find#find): raise with the given path name if it
-	  does not exist.  [ruby-dev:49497] [Bug #12087]
-
-Fri Feb 19 12:44:57 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Activated use of case mapping data in CaseUnfold_11 array.
-	  (with Kimihito Matsui)
-
-Fri Feb 19 11:08:32 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/extmk.rb: add cygwin case, nothing excluded.
-	  [ruby-core:73806] [Bug#12071]
-
-Thu Feb 18 21:32:15 2016  Kazuhiro NISHIYAMA  <zn@mbf.nifty.com>
-
-	* man/irb.1: fix output in EXAMPLES.
-
-Thu Feb 18 21:05:47 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* string.c (sym_match_m): delegate to String#match but not
-	  String#=~.  [ruby-core:72864] [Bug #11991]
-
-Thu Feb 18 14:15:38 2016  Shota Fukumori  <her@sorah.jp>
-
-	* re.c: Add MatchData#named_captures
-	  [Feature #11999] [ruby-core:72897]
-
-	* test/ruby/test_regexp.rb(test_match_data_named_captures): Test for above.
-
-	* NEWS: News about MatchData#named_captures.
-
-Wed Feb 17 21:41:29 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* defs/id.def (predefined): add idLASTLINE and idBACKREF for $_
-	  and $~ respectively.
-
-	* parse.y: use idLASTLINE and idBACKREF instead of rb_intern.
-
-Wed Feb 17 20:23:38 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* string.c (rb_str_init): fix segfault and memory leak, consider
-	  wide char encoding terminator.
-
-Wed Feb 17 12:14:59 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* string.c (rb_str_init): introduce String.new(capacity: size)
-	  [Feature #12024]
-
-Tue Feb 16 19:10:08 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode/case-folding.rb, casefold.h: Used only first element
-	  (rather than all) of target in CaseUnfold_11 array.
-	  (with Kimihito Matsui)
-
-Tue Feb 16 18:24:38 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* numeric.c (compare_with_zero): fix variable name, rb_cmperr
-	  requires VALUEs but not an ID.
-
-Tue Feb 16 17:34:18 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* dir.c (rb_dir_s_empty_p): add Dir.empty? method, which tells the
-	  argument is the name of an empty directory.  [Feature #10121]
-
-Tue Feb 16 09:51:20 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* tool/rbinstall.rb (without_destdir): just strip a drive letter
-	  which is prepended by with_destdir.
-	  pointed out by @DavidEGrayson.
-	  https://github.com/ruby/ruby/commit/0e5f9ae#commitcomment-16101763
-
-Tue Feb 16 04:42:13 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* insns.def (opt_plus): simply use LONG2NUM() instead of wrongly
-	  complex overflow case.
-
-	* insns.def (opt_sub): ditto.
-
-Tue Feb 16 02:49:41 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* tool/rbinstall.rb (without_destdir): compare with the destdir
-	  after stripping a drive letter, on dosish platforms.
-	  pointed out by @DavidEGrayson.
-	  https://github.com/ruby/ruby/commit/d0cf23b#commitcomment-16100407
-
-Mon Feb 15 15:44:09 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* parse.y (parse_ident): allow keyword arguments just after a
-	  method where the same name local variable is defined.
-	  [ruby-core:73816] [Bug#12073]
-
-Mon Feb 15 14:43:28 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode/case-folding.rb: Added debugging option
-	  (with Kimihito Matsui)
-
-Sun Feb 14 17:31:50 2016  Lars Kanis  <lars@greiz-reinsdorf.de>
-
-	* lib/mkmf.rb (with_{cpp,c,ld}flags): copy caller strings not to
-	  be modified, in append_{cpp,c,ld}flags respectively.
-	  [Fix GH-1246]
-
-Sun Feb 14 16:18:57 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* eval.c (setup_exception): set the cause only if it is explicitly
-	  given or not set yet.  [Bug #12068]
-
-Sat Feb 13 21:44:58 2016  Tanaka Akira  <akr@fsij.org>
-
-	* hash.c (rb_hash_invert): [DOC] more examples.
-
-Sat Feb 13 17:30:49 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/uri/generic.rb (URI::Generic#find_proxy): support CIDR in
-	  no_proxy.  [ruby-core:73769] [Feature#12062]
-
-Sat Feb 13 17:11:58 2016  Fabian Wiesel  <fabian.wiesel@sap.com>
-
-	* lib/uri/generic.rb (find_proxy): exclude white-spaces and allow
-	  for a leading dot in the domain name in no_proxy.
-	  [ruby-core:54542] [Feature #8317]
-
-Fri Feb 12 12:20:56 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* error.c (name_err_initialize, nometh_err_initialize): [DOC] fix
-	  argument positions.  optional parameters except for the message
-	  are placed at the last.
-
-Fri Feb 12 11:49:49 2016  Anthony Dmitriyev  <antstorm@gmail.com>
-
-	* net/ftp.rb: add NullSocket#closed? to fix closing not opened
-	  connection.  [Fix GH-1232]
-
-Fri Feb 12 11:17:38 2016  Bogdan  <bogdanvlviv@gmail.com>
-
-	* re.c (rb_reg_initialize_m): [DOC] fix missing right bracket.
-	  [Fix GH-1243]
-
-Thu Feb 11 14:57:58 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* configure.in (RUBY_CHECK_SIZEOF, RUBY_DEFINT): fix for types
-	  which are conditionally available depending on architectures
-	  when universal binary, e.g., __int128.
-
-Thu Feb 11 06:26:18 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* configure.in (RUBY_DEFINT): use Parameter Expansion.
-
-Thu Feb 11 05:33:24 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* configure.in (int128_t): don't check HAVE_XXX (for example
-	  HAVE___INT128) because RUBY_CHECK_SIZEOF() don't define it for
-	  config.h and use of $ac_cv_sizeof___int128 alternates the check.
-	  (and don't need to define because users shouldn't know that)
-
-Wed Feb 10 12:03:41 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* configure.in (ARFLAGS): check if deterministic mode flag is
-	  effective, which is on by default on Ubuntu.
-
-Tue Feb  9 16:36:23 2016  Naotoshi Seo  <sonots@gmail.com>
-
-	* lib/logger.rb: Remove block from Logger.add as it's not needed
-	  patch provided by Daniel Lobato Garcia [fix GH-1240] [Bug #12054]
-
-Tue Feb  9 14:32:23 2016  Zachary Scott  <zzak@ruby-lang.org>
-
-	* ext/zlib/zlib.c: Document mtime header behavior with patch by @schneems
-	  Fixes [GH-1129]: https://github.com/ruby/ruby/pull/1129
-
-Tue Feb  9 13:52:49 2016  Zachary Scott  <zzak@ruby-lang.org>
-
-	* re.c: Remove deprecated kcode argument from Regexp.new and compile
-	  patch provided by Dylan Pulliam [Bug #11495]
-
-Mon Feb  8 21:26:19 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode/case-folding.rb, enc/unicode/casefold.h: Flags for
-	  upper/lower conversion added (titlecase and SpecialCasing still missing)
-	  (with Kimihito Matsui)
-
-Mon Feb  8 20:43:57 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c, enc/unicode.c: Disassociating ONIGENC_CASE_FOLD flag from
-	  ONIGENC_CASE_DOWNCASE.
-	  (with Kimihito Matsui)
-
-Mon Feb  8 13:00:17 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Shortened macros for enc/unicode/casefold.h to
-	  single-letter; use flags in casefold.h for logic.
-
-	* enc/unicode/case-folding.rb: Added flag for case folding.
-	  Changed parameter passing.
-
-	* enc/unicode/casefold.h: New flags added.
-	  (with Kimihito Matsui)
-
-Mon Feb  8 10:30:10 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ruby.c (feature_option): raise a runtime error if ambiguous
-	  feature name is given, in the future.  [Bug #12050]
-
-Mon Feb  8 09:43:57 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* common.mk: Removed enc/unicode/casefold.h from automatic build because
-	  some CI systems don't have gperf. Creation of enc/unicode/casefold.h
-	  is now possible with make unicode-up. This is intended as a temporary measure.
-
-Sun Feb  7 22:10:08 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* common.mk: Added two more precondition files for enc/unicode/casefold.h
-
-	* enc/unicode.c: Added shortening macros for enc/unicode/casefold.h
-
-	* enc/unicode/case-folding.rb: Fixed file encoding for CaseFolding.txt
-	  to ASCII-8BIT (should fix some ci errors). Clarified usage. Created
-	  class MapItem. Partially implemented class CaseMapping.
-	  (with Kimihito Matsui)
-
-Sun Feb  7 14:12:32 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode/case-folding.rb: Fixing parameter passing.
-	  (with Kimihito Matsui)
-
-Sun Feb  7 11:44:03 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode/case-folding.rb: New classes CaseMapping/CaseMappingDummy
-	  to pass as parameters; not yet implemented or used.
-	  (with Kimihito Matsui)
-
-Sun Feb  7 11:16:00 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* common.mk: using new option in recipe for enc/unicode/casefold.h
-
-	* enc/unicode/case-folding.rb: Correctly specify argument to new option.
-	  (with Kimihito Matsui)
-
-Sun Feb  7 10:43:27 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	(this commit message applies to the previous commit)
-	* common.mk: explicit recipe for enc/unicode/casefold.h
-
-	* enc/unicode/case-folding.rb: Adding -m option to prepare for using
-	  multiple data files.
-	  (with Kimihito Matsui)
-
-Sat Feb  6 22:30:57 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/cgi/util.rb (escapeHTML, unescapeHTML): consider
-	  ASCII-incompatible encodings.  [Fix GH-1239]
-
-Sat Feb  6 15:18:28 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_regex_casefold.rb: Added data-based testing for
-	  String#downcase :fold.
-
-	* enc/unicode.c: Fixed a range error (lowest non-ASCII character affected
-	  by case operations is U+00B5, MICRO SIGN)
-
-	* test/ruby/enc/test_case_mapping.rb: Explicit test for case folding of
-	  MICRO SIGN to Greek mu.
-	  (with Kimihito Matsui)
-
-Sat Feb  6 14:51:23 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_regex_casefold.rb: Tests for three case folding
-	  primitives (mbc_case_fold, get_case_fold_codes_by_str,
-	  apply_all_case_fold) in the various encodings. Currently only known
-	  good encodings are tested to avoid test failures. For bug hunting,
-	  start by adding more encodings with
-	  generate_test_casefold encoding
-	  (with Kimihito Matsui)
-
-Sat Feb  6 14:37:16 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c, test/ruby/enc/test_case_mapping.rb: Implemented :fold
-	  option for String#downcase by using case folding data from
-	  regular expression engine, and added a few simple tests.
-	  (with Kimihito Matsui)
-
-Fri Feb  5 20:08:59 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_case_mapping.rb: added tests for :ascii option.
-	  (with Kimihito Matsui)
-
-Fri Feb  5 12:22:20 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* insns.def (opt_mult): Use int128_t for overflow detection.
-
-	* bignum.c (rb_uint128t2big): added for opt_mult.
-
-	* bignum.c (rb_uint128t2big): added for rb_uint128t2big..
-
-	* configure.in: define int128_t, uint128_t and related MACROs.
-	  Initially introduced by r41379 but reverted by r50749.
-
-Thu Feb  4 21:05:17 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Activated :ascii flag for ASCII-only case conversion
-	  (with Kimihito Matsui)
-
-Thu Feb  4 17:38:01 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* re.c (reg_set_source): make source string frozen without
-	  copying.
-
-	* re.c (rb_reg_initialize_m): refactor initialization with
-	  encoding.
-
-Thu Feb  4 15:35:29 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* string.c (rb_fstring_enc_new, rb_fstring_enc_cstr): functions to
-	  make fstring with encoding.
-
-Thu Feb  4 14:42:29 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* common.mk: Added Unicode data file SpecialCasing.txt to be additionally
-	  downloaded (with Kimihito Matsui)
-
-Thu Feb  4 12:39:08 2016  joker1007  <kakyoin.hierophant@gmail.com>
-
-	* cgi/escape/escape.c: Optimize CGI.escape performance by C ext
-	  for ASCII-compatible encodings.  [Fix GH-1238]
-
-Thu Feb  4 11:53:56 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* common.mk: Introduce two variables (UNICODE_DATA_DIR and
-	  UNICODE_SRC_DATA_DIR) to eliminate repetitions.
-
-Wed Feb  3 12:13:20 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* string.c (str_new_frozen): if the given string is embeddedable
-	  but not embedded, embed a new copied string. [Bug #11946]
-
-Wed Feb  3 08:25:38 2016  boshan  <boshan@subsplash.com>
-
-	* ext/openssl/ossl_pkey.c (Init_ossl_pkey): [DOC] Fix typo
-	  "encrypted" to "decrypted".  [Fix GH-1235]
-
-Wed Feb  3 08:21:32 2016  Seiei Miyagi  <hanachin@gmail.com>
-
-	* ext/ripper/lib/ripper/lexer.rb (on_heredoc_dedent): Fix
-	  Ripper.lex error in dedenting squiggly heredoc.  heredoc tree is
-	  also an array of Elem in the outer tree.  [Fix GH-1234]
-
-Wed Feb  3 02:33:39 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* re.c (rb_reg_prepare_enc): use already compiled US-ASCII regexp
-	  if given string is ASCII only.
-	  121.2s to 113.9s on my x86_64-freebsd10.2 Intel Core i5 661
-
-Tue Feb  2 13:02:03 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* re.c: Introduce RREGEXP_PTR.
-	  patch by dbussink.
-	  partially merge https://github.com/ruby/ruby/pull/497
-
-	* include/ruby/ruby.h: ditto.
-
-	* gc.c: ditto.
-
-	* ext/strscan/strscan.c: ditto.
-
-	* parse.y: ditto.
-
-	* string.c: ditto.
-
-Tue Feb  2 09:08:27 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/rubygems/specification.rb: `coding` is effective only first
-	  line except shebang.
-
-	* lib/rubygems/package.rb, lib/rubygems/package/*: ditto.
-
-Mon Feb  1 21:41:58 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/rubygems.rb, lib/rubygems/*, test/rubygems/*: Update rubygems-2.5.2.
-	  It supports to enable frozen string literal and add `--norc` option for
-	  disable to `.gemrc` configuration.
-	  See 2.5.2 release notes for other fixes and enhancements.
-	  https://github.com/rubygems/rubygems/blob/a8aa3bac723f045c52471c7b9328310a048561e0/History.txt#L3
-
-Sun Jan 31 12:33:13 2016  Dan Kreiger  <dan@dankreiger.com>
-
-	* test/drb/ut_large.rb (multiply, avg, median): add additional
-	  math operations to DRbLarge.  [Fix GH-1086]
-
-Sun Jan 31 12:19:15 2016  Kuniaki IGARASHI  <igaiga@gmail.com>
-
-	* test/ruby/test_file_exhaustive.rb (test_lstat): Add lacking test
-	  for File#lstat.  [Fix GH-1231]
-
-Sun Jan 31 12:15:33 2016  Prayag Verma  <prayag.verma@gmail.com>
-
-	* doc/standard_library.rdoc: fix typo  [Fix GH-1230]
-	  Spelling mistakes -
-	  outputing > outputting
-	  publich > publish
-
-Sat Jan 30 15:18:07 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* vm_eval.c (rb_check_funcall_with_hook): also should call the
-	  given hook before returning Qundef when overridden respond_to?
-	  method returned false.  [ruby-core:73556] [Bug #12030]
-
-Fri Jan 29 17:40:07 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* win32/file.c (rb_readlink): drop garbage after the substitute
-	  name, as rb_w32_read_reparse_point returns the expected buffer
-	  size but "\??\" prefix is dropped from the result.
-
-	* win32/win32.c (w32_readlink): ditto, including NUL-terminator.
-
-Fri Jan 29 17:07:27 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* win32/win32.c (fileattr_to_unixmode, rb_w32_reparse_symlink_p): volume
-	  mount point should be treated as directory, not symlink.
-	  [ruby-core:72483] [Bug #11874]
-
-	* win32/win32.c (rb_w32_read_reparse_point): check the reparse point is
-	  a volume mount point or not.
-
-	* win32/file.c (rb_readlink): follow above change (but this pass won't
-	  be used).
-
-Fri Jan 29 16:17:07 2016  Lucas Buchala  <lucasbuchala@gmail.com>
-
-	* enum.c (enum_take_while, enum_drop_while): rename block
-	  parameter to obj, since they are generic objects.  [Fix GH-1226]
-
-Fri Jan 29 14:15:26 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/erb.rb (ERB::Compiler#detect_magic_comment): allow
-	  frozen-string-literal in comment as well as encoding.
-
-	* lib/erb.rb (ERB#def_method): insert def line just before the
-	  first non-comment and non-empty line, not to leave duplicated
-	  and stale magic comments.
-
-Fri Jan 29 11:13:33 2016  Jeremy Evans  <code@jeremyevans.net>
-
-	* lib/erb.rb (ERB#set_eoutvar): explicitly make mutable string as
-	  a buffer to make ERB work with --enable-frozen-string-literal.
-	  [ruby-core:73561] [Bug #12031]
-
-Fri Jan 29 10:44:56 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/net/http/header.rb: Warn nil variable on HTTP Header.
-	  It caused to NoMethodError. [fix GH-952][fix GH-641] Patch by @teosz
-	* test/net/http/test_httpheader.rb: Added test for nil HTTP Header.
-
-Thu Jan 28 17:31:43 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/socket/socket.c (sock_gethostname): support unlimited size
-	  hostname.
-
-Wed Jan 27 21:03:45 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* test/-ext-/string/test_capacity.rb: Added missing library.
-
-Wed Jan 27 18:53:40 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Fixed bit mask in macro OnigCodePointCount
-
-Wed Jan 27 17:54:42 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Protect code point count by macro, in order to
-	  be able to use the remaining bits for flags.
-	  (with Kimihito Matsui)
-
-Wed Jan 27 16:34:35 2016  boshan  <boshan@subsplash.com>
-
-	* lib/tempfile.rb (Tempfile#initialize): [DOC] the first parameter
-	  `basename` is optional and defaulted to an empty string since
-	  [GH-523].  [Fix GH-1225]
-
-Wed Jan 27 16:25:54 2016  Koichi ITO  <koic.ito@gmail.com>
-
-	* array.c (rb_ary_dig): [DOC] fix the exception class to be raised
-	  when intermediate object does not have dig method.  TypeError
-	  will be raised now.  [Fix GH-1224]
-
-Tue Jan 26 19:36:15 2016  Aggelos Avgerinos  <evaggelos.avgerinos@gmail.com>
-
-	* array.c (permute0, rpermute0): [DOC] Substitute indexes ->
-	  indices in documentation for consistency.  [Fix GH-1222]
-
-Tue Jan 26 15:21:37 2016  Eric Wong  <e@80x24.org>
-
-	* compile.c (caller_location): use rb_fstring_cstr for "<compiled>"
-	  (it is converted to fstring anyways inside rb_iseq_new_with_opt)
-	* iseq.c (iseqw_s_compile): ditto
-	* iseq.c (rb_iseq_new_main): use rb_fstring_cstr for "<main>"
-	* vm.c (Init_VM): ditto, share with with above
-	* iseq.c (iseqw_s_compile_file): rb_fstring before rb_io_t->pathv
-	  share "<main>" with above
-	* vm.c (rb_binding_add_dynavars): fstring "<temp>" immediately
-
-Tue Jan 26 15:14:01 2016  Kazuki Yamaguchi  <k@rhe.jp>
-
-	* compile.c (iseq_peephole_optimize): don't apply tailcall
-	  optimization to send/invokesuper instructions with blockiseq.
-	  This is a follow-up to the changes in r51903; blockiseq is now
-	  the third operand of send/invokesuper instructions.
-	  [ruby-core:73413] [Bug #12018]
-
-Tue Jan 26 14:26:46 2016  Eric Wong  <e@80x24.org>
-
-	* signal.c (sig_list): use fstring for hash key
-	* test/ruby/test_signal.rb (test_signal_list_dedupe_keys): added
-
-Tue Jan 26 13:08:34 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* signal.c (rb_f_kill): should immediately deliver reserved
-	  signals SIGILL and SIGFPE, not only SIGSEGV and SIGBUS.
-
-Tue Jan 26 07:57:28 2016  Joseph Tibbertsma  <josephtibbertsma@gmail.com>
-
-	* gc.c (RVALUE_PAGE_WB_UNPROTECTED): fix a typo of argument name.
-	  [Fix GH-1221]
-
-Mon Jan 25 17:26:54 2016  Eric Wong  <e@80x24.org>
-
-	* ruby_assert.h (RUBY_ASSERT_WHEN): fix reference to macro name
-	* vm_core.h: include ruby_assert.h before using
-	  [ruby-core:73371]
-
-Mon Jan 25 15:55:30 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* symbol.c (sym_check_asciionly): more informative error message
-	  with the encoding name and the inspected content.
-	  [ruby-core:73398] [Feature #12016]
-
-Mon Jan 25 09:38:26 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* test/ruby/test_string.rb: added testcase for next!, succ and succ!
-	  [fix GH-1213] Patch by @K0mAtoru
-
-Mon Jan 25 09:32:25 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/webrick/httpservlet/filehandler.rb: fix documentation for namespace.
-	  [fix GH-1219][ci skip] Patch by @leafac
-
-Sun Jan 24 19:34:23 2016  Eric Wong  <e@80x24.org>
-
-	* vm_insnhelper.c (vm_check_if_namespace): tiny size reduction
-
-Sun Jan 24 18:12:36 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* common.mk: Simplifying Unicode data file download logic to make
-	  it more reliable (including additional fix not in r53633) [Bug #12007]
-
-Sun Jan 24 16:54:11 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/io/wait/wait.c (io_wait_readwrite): [EXPERIMENTAL] allow to
-	  wait for multiple modes, readable and writable, at once.  the
-	  arguments may change in the future.  [Feature #12013]
-
-Sat Jan 23 22:30:59 2016  K0mA  <mctj1218@gmail.com>
-
-	* test/ruby/test_array.rb (test_keep_if): Add test for
-	  Array#keep_if separate from Array#select!  [Fix GH-1218]
-
-Sat Jan 23 20:54:26 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* common.mk: revert r53633. It broke rubyci and travis.
-	  https://travis-ci.org/ruby/ruby/builds/104259623
-
-Sat Jan 23 20:10:29 2016  Shugo Maeda  <shugo@ruby-lang.org>
-
-	* range.c (range_eqq): revert r51585 because rb_call_super() is
-	  called in range_include() and thus r51585 doesn't work when the
-	  receiver Range object consists of non linear objects such as Date
-	  objects.
-	  [ruby-core:72908] [Bug #12003]
-
-Sat Jan 23 18:37:37 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* ChangeLog: Fixing wrong time on previous commit, and adding
-	  previous commit message to svn [ci skip]
-
-Sat Jan 23 18:30:30 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* common.mk: Simplifying Unicode data file download logic to make
-	  it more reliable [Bug #12007]
-
-Sat Jan 23 16:29:42 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* tool/downloader.rb: Fixed a logical error, improved documentation
-
-Sat Jan 23 11:42:43 2016  Peter Suschlik  <ps@neopoly.de>
-
-	* README.md: Use SVG Travis badge over PNG for better quality and
-	  device support.  [Fix GH-1214] [Fix GH-1216]
-
-Sat Jan 23 11:29:16 2016  Pascal Betz  <pascal.betz@simplificator.com>
-
-	* lib/csv.rb: Update documentation of CSV header converter for
-	  r45498, [GH-575].  [Fix GH-1215]
-
-Fri Jan 22 17:36:46 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* vm_core.h (VM_ASSERT): use RUBY_ASSERT instead of rb_bug.
-
-	* error.c (rb_assert_failure): assertion with stack dump.
-
-	* ruby_assert.h (RUBY_ASSERT): new header for the assertion.
-
-Fri Jan 22 00:25:57 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* regparse.c (fetch_name_with_level): allow non word characters
-	  at the first character.  [Feature #11949]
-
-	* regparse.c (fetch_name): ditto.
-
-Thu Jan 21 17:34:01 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* marshal.c (r_object0): honor Marshal.load post proc
-	  value for TYPE_LINK.  by Hiroshi Nakamura <nahi@ruby-lang.org>
-	  https://github.com/ruby/ruby/pull/1204 fix GH-1204
-
-Thu Jan 21 16:37:50 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* Makefile.in (update-rubyspec): fix r53208 like r53451.
-
-Wed Jan 20 20:58:25 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* common.mk, Makefile.in: update-config_files is only for Unix
-	  platforms.
-
-Wed Jan 20 17:13:39 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* tool/extlibs.rb: add --cache option to change cache directory.
-
-Tue Jan 19 17:03:40 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* common.mk: Added Unicode data file CaseFolding.txt to be additionally
-	  downloaded (with Kimihito Matsui)
-
-Tue Jan 19 10:09:58 2016  Sho Hashimoto  <sho-h@ruby-lang.org>
-
-	* lib/shell.rb (Shell.debug_output_exclusive_unlock): remove
-	  because Mutex#exclusive_unlock was already deleted. [fix GH-1185]
-
-Tue Jan 19 09:38:27 2016  Nick Cox  <nick@nickcox.me>
-
-	* vm_method.c: fix grammar in respond_to? warning.
-	  [fix GH-1047]
-
-Mon Jan 18 14:37:07 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* parse.y (parser_here_document): an escaped newline is not an
-	  actual newline, and the rest part should not be dedented.
-	  [ruby-core:72855] [Bug #11989]
-
-Mon Jan 18 12:04:34 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* test/ruby/test_string.rb: Added extra testcase for test_rstrip_bang
-	  and test_lstrip_bang. [fix GH-1178] Patch by @Matrixbirds
-
-Mon Jan 18 11:47:27 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* string.c: fix a typo. [fix GH-1202][ci skip] Patch by @sunboshan
-
-Sun Jan 17 21:15:30 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* configure.in: improve ICC (Intel C Compiler) support.
-
-	* configure.in (CXX): The name of icc's c++ compiler is `icpc`.
-
-	* configure.in (warnings): Add `-diag-disable=2259` to suppress
-	  noisy warnings: "non-pointer conversion from "..." to "..." may
-	  lose significant bits".
-
-	* configure.in (optflags): Add `-fp-model precise` like -fno-fast-math.
-
-	* lib/mkmf.rb: icc supports -Werror=division-by-zero
-	  and -Werror=deprecated-declarations, but doesn't support
-	  -Wdivision-by-zero and -Wdeprecated-declarations.
-
-Sun Jan 17 20:40:10 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c: Any kind of option is now taking the new code path for
-	  upcase/downcase/capitalize/swapcase. :lithuanian can be used for
-	  testing if no specific option is desired.
-	* test/ruby/enc/test_case_mapping.rb: Adjusted to above.
-	  (with Kimihito Matsui)
-
-Sun Jan 17 20:10:10 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Fixed a logical error and some comments.
-	* test/ruby/enc/test_case_mapping.rb: Made tests more general.
-	  (with Kimihito Matsui)
-
-Sun Jan 17 17:41:41 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Removed artificial expansion for Turkic,
-	  added hand-coded support for Turkic, fixed logic for swapcase.
-	* string.c: Made use of new case mapping code possible from upcase,
-	  capitalize, and swapcase (with :lithuanian as a guard).
-	* test/ruby/enc/test_case_mapping.rb: Adjusted for above.
-	  (with Kimihito Matsui)
-
-Sun Jan 17 15:30:57 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/socket/option.c (sockopt_bool): relax boolean size to be one
-	  too not only sizeof(int).  Winsock getsockopt() returns a single
-	  byte as a boolean socket option.  [ruby-core:72730] [Bug #11958]
-
-Sun Jan 17 14:43:01 2016  Kuniaki IGARASHI  <igaiga@gmail.com>
-
-	* test/ruby/test_env.rb: [Fix GH-1201]
-	  * Extract test code for ENV#keep_if from ENV#select_bang
-	  * Add a test case for ENV#select_bang,keep_if
-
-Sun Jan 17 14:42:25 2016  Kuniaki IGARASHI  <igaiga@gmail.com>
-
-	* test/ruby/test_env.rb: [Fix GH-1201]
-	  * Extract test code for ENV#delete_if from ENV#reject_bang
-	  * Add a test case for ENV#reject_bang,delete_if
-
-Sun Jan 17 14:40:22 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ext/socket/option.c (check_size): extract a macro to check
-	  binary data size, with a consistent message.
-
-	* ext/socket/option.c (sockopt_byte): fix error message,
-	  sizeof(int) differs from sizeof(unsigned char) in general.
-
-Sat Jan 16 21:16:21 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* parse.y (xstring): reset heredoc indent after dedenting,
-	  so that following string literal would not be dedented.
-	  [ruby-core:72857] [Bug #11990]
-
-Sat Jan 16 17:24:24 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* enc/unicode.c: Artificial mapping to test buffer expansion code.
-	* string.c: Fixed buffer expansion logic.
-	* test/ruby/enc/test_case_mapping.rb: Tests for above.
-	  (with Kimihito Matsui)
-
-Sat Jan 16 16:47:14 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* ext/openssl/lib/openssl/pkey.rb: Added 2048 bit DH parameter.
-	* test/openssl/test_pkey_dh.rb: ditto.
-
-Sat Jan 16 10:51:19 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* enc/unicode.c: fix implicit conversion error with clang. fixup r53548.
-	* string.c: ditto.
-
-Sat Jan 16 10:31:00 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* common.mk: test-sample was changed to test-basic.
-	  [Feature #11982][ruby-core:72823]
-	* basictest/runner.rb: ditto. rename from tool/rubytest.rb.
-	* basictest/test.rb: ditto. rename from sample/test.rb.
-	* defs/gmake.mk: picked from r53540
-	* sample/test.rb: backward compatibility for chkbuild.
-
-Sat Jan 16 10:23:23 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c, enc/unicode.c: New code path as a preparation for Unicode-wide
-	  case mapping. The code path is currently guarded by the :lithuanian
-	  option to avoid accidental problems in daily use.
-	* test/ruby/enc/test_case_mapping.rb: Test for above.
-	* string.c: function 'check_case_options': fixed logical errors
-	  (with Kimihito Matsui)
-
-Fri Jan 15 20:20:20 2016  Naohisa Goto  <ngotogenome@gmail.com>
-
-	* regint.h (PLATFORM_UNALIGNED_WORD_ACCESS): The value of
-	  UNALIGNED_WORD_ACCESS should be used to determine whether
-	  unaligned word access is allowed or not. After this commit,
-	  ./configure CPPFLAGS="-DUNALIGNED_WORD_ACCESS=0" disables
-	  unaligned word access even on platforms that support the feature.
-
-Fri Jan 15 16:12:10 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* parse.y (string1): reset heredoc indent for each string literal
-	  so that concatenated string would not be dedented.
-	  [ruby-core:72857] [Bug #11990]
-
-Thu Jan 14 20:01:00 2016  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* lib/uri/generic.rb (URI::Generic#to_s): change encoding to
-	  UTF-8 as Ruby 2.2/ by Koichi ITO <koic.ito@gmail.com>
-	  https://github.com/ruby/ruby/pull/1188 fix GH-1188
-
-Thu Jan 14 17:36:16 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* variable.c (rb_f_global_variables): add matched back references
-	  only, as well as defined? operator.
-
-Thu Jan 14 16:12:09 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* sprintf.c (rb_str_format): format exact number more exactly.
-
-Thu Jan 14 15:08:43 2016  Tony Arcieri  <bascule@gmail.com>
-
-	* Remove 512-bit DH group. It's affected by LogJam Attack.
-	  https://weakdh.org/
-	  [fix GH-1196][Bug #11968][ruby-core:72766]
-
-Thu Jan 14 11:44:29 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* variable.c (rb_f_global_variables): add $1..$9 only if $~ is
-	  set.  fix the condition removed at r14014.
-
-Wed Jan 13 17:21:45 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* .travis.yml: removed commented-out code.
-
-Wed Jan 13 17:14:54 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* .travis.yml: removed osx code. follow up with r53517
-
-Wed Jan 13 16:56:19 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* iseq.c (rb_iseq_mark): mark parent iseq to prevent dynamically
-	  generated iseq by eval from GC.  [ruby-core:72620] [Bug #11928]
-
-Wed Jan 13 03:42:58 2016  Eric Wong  <e@80x24.org>
-
-	* class.c (Init_class_hierarchy): resolve name for rb_cObject ASAP
-	* object.c (rb_mod_const_set): move name resolution to rb_const_set
-	* variable.c (rb_const_set): do class resolution here
-	  [ruby-core:72807] [Bug #11977]
-
-Wed Jan 13 00:37:12 2016  Satoshi Ohmori  <sachin21dev@gmail.com>
-
-	* man/ruby.1: fix double word typo.  [Fix GH-1194]
-
-Tue Jan 12 21:01:09 2016  Benoit Daloze  <eregontp@gmail.com>
-
-	* common.mk: update URL and name for the Ruby spec suite.
-
-Tue Jan 12 19:52:19 2016  sorah (Shota Fukumori)  <her@sorah.jp>
-
-	* lib/forwardable.rb: Convert given accessors to String.
-
-	  r53381 changed to accept only Symbol or String for accessors, but
-	  there are several rubygems that pass classes (e.g. Array,
-	  Hash, ...) as accessors. Prior r53381, it was accepted because Class#to_s
-	  returns its class name. After r53381 given accessors are checked
-	  with define_method, but it accepts only Symbol or String, otherwise
-	  raises TypeError.
-
-	      def_delegator Foo, :some_method
-
-	  This change is to revert unexpected incompatibility. But this behavior
-	  may change in the future.
-
-Mon Jan 12 18:41:41 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c: made a variable name more grammatically correct
-
-Mon Jan 12 18:34:34 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c: minor grammar fix [ci skip]
-
-Mon Jan 12 16:09:09 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* test/ruby/enc/test_casing_options.rb: Tests for option
-	  parsing/checking for upcase/downcase/capitalize/swapcase
-	  (see r53503; with Kimihito Matsui)
-
-Mon Jan 12 16:03:03 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* string.c: Added option parsing/checking for upcase/downcase/
-	  capitalize/swapcase (with Kimihito Matsui)
-
-Mon Jan 11 21:28:28 2016  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* include/ruby/oniguruma.h: Added flags needed for upcase/downcase
-	  Unicode addition (with Kimihito Matsui)
-
-Mon Jan 11 09:50:24 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* configure.in: check if the API version number is consistent with
-	  the program version number.
-
-Sun Jan 10 20:57:25 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* compile.c (compile_massign_lhs): when index ends with splat,
-	  append rhs value to it like POSTARG, since VM_CALL_ARGS_SPLAT
-	  splats the last argument only.  [ruby-core:72777] [Bug #11970]
-
-Sun Jan 10 15:45:10 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/missing.h (explicit_bzero_by_memset_s): remove
-	  inline implementation by memset_s, which needs a macro before
-	  including headers and can cause problems in extension libraries
-	  by the order of the macro and headers.
-
-Sun Jan 10 13:41:36 2016  Eric Wong  <e@80x24.org>
-
-	* io.c (rb_deferr): remove long obsolete global
-
-Sun Jan 10 09:14:42 2016  Eric Wong  <e@80x24.org>
-
-	* ext/psych/lib/psych/visitors/yaml_tree.rb (visit_String):
-	  eliminate chomp
-	* lib/net/http.rb (connect): eliminate delete
-	* lib/net/http/header.rb (basic_encode): ditto
-	* lib/net/imap.rb (authenticate): eliminate gsub
-	  (self.encode_utf7): shorten delete arg
-	* lib/net/smtp.rb (base64_encode): eliminate gsub
-	* lib/open-uri.rb (OpenURI.open_http): eliminate delete
-	* lib/rss/rss.rb: ditto
-	* lib/securerandom.rb (base64): ditto
-	  (urlsafe_base64): eliminate delete!
-	* lib/webrick/httpauth/digestauth.rb (split_param_value):
-	  eliminate chop
-	* lib/webrick/httpproxy.rb (do_CONNECT): eliminate delete
-	  (setup_upstream_proxy_authentication): ditto
-	  [ruby-core:72666] [Feature #11938]
-
-Sat Jan  9 23:19:14 2016  Kuniaki IGARASHI  <igaiga@gmail.com>
-
-	* test/ruby/test_hash.rb (test_try_convert): Add test for
-	  Hash.try_convert.  [Fix GH-1190]
-
-Sat Jan  9 23:15:25 2016  Jon Moss  <maclover7@users.noreply.github.com>
-
-	* ext/openssl/ossl.c: Add missing variables to documentation
-	  examples.  [Fix GH-1189]
-
-Sat Jan  9 18:25:57 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* symbol.h (is_attrset_id): ASET is an attrset ID.  fix
-	  unexpected safe call instead of an ordinary ASET.
-
-Sat Jan  9 10:44:33 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* configure.in, win32/setup.mak: extract RUBY_PROGRAM_VERSION from
-	  RUBY_VERSION in version.h instead of RUBY_API_VERSION numbers in
-	  include/ruby/version.h, and cut it into version numbers.
-
-Sat Jan  9 07:13:33 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c: rename PAGE_* to HEAP_PAGE_* because PAGE_SIZE is used
-	  in Mac OS X.
-
-	* test/ruby/test_gc.rb: catch up this fix.
-
-Sat Jan  9 05:45:40 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c: PAGE_BITMAP_PLANES (the number of bitmap) is 4, not 3.
-
-Sat Jan  9 05:42:57 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c: rename constant names HEAP_* to PAGE_*.
-
-	  Keys of GC::INTERNAL_CONSTANTS are also renamed.
-
-	* test/ruby/test_gc.rb: catch up this fix.
-
-Fri Jan  8 22:30:06 2016  Akinori MUSHA  <knu@iDaemons.org>
-
-	* doc/regexp.rdoc: [DOC] Elaborate on the \G anchor. [ci skip]
-
-Fri Jan  8 19:49:27 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c: remove heap_page::body. Instead of this field,
-	  heap_page::start field works well.
-
-Fri Jan  8 19:31:52 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c: rename rb_heap_t::page_length to rb_heap_t::total_pages.
-
-	  `page_length' is not clear (we may understand with length of
-	  a page).
-
-Fri Jan  8 17:07:14 2016  Koichi Sasada  <ko1@atdot.net>
-
-	* gc.c: remove heap_page::heap. This field is only used to recognize
-	  whether a page is in a tomb or not. Instead of this field,
-	  heap_page::flags::in_tomb (1 bit field) is added.
-
-	  Also type of heap_page::(total|free|final)_slots are changed from
-	  int to short. 2B is enough for them.
-
-Fri Jan  8 09:33:59 2016  Shugo Maeda  <shugo@ruby-lang.org>
-
-	* iseq.c (rb_iseq_compile_with_option): move variable initialization
-	  code to avoid maybe-uninitialized warnings by gcc 4.8.
-
-Fri Jan  8 00:03:22 2016  Shugo Maeda  <shugo@ruby-lang.org>
-
-	* enum.c (enum_min, enum_max): do the same optimization as r53454.
-
-Thu Jan  7 22:32:21 2016  Kenta Murata  <mrkn@mrkn.jp>
-
-	* ruby.h: undef HAVE_BUILTIN___BUILTIN_CHOOSE_EXPR_CONSTANT_P
-	  and HAVE_BUILTIN___BUILTIN_TYPES_COMPATIBLE_P on C++.
-	  [ruby-core:72736] [Bug #11962]
-
-Thu Jan  7 22:02:21 2016  Shugo Maeda  <shugo@ruby-lang.org>
-
-	* enum.c (enum_minmax): optimize object comparison in
-	  Enumerable#minmax.
-
-Thu Jan  7 14:49:12 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* thread.c (rb_thread_pending_interrupt_p): no pending interrupt
-	  before initialization.
-
-	* thread.c (thread_raise_m, rb_thread_kill): uninitialized thread
-	  cannot interrupt.  [ruby-core:72732] [Bug #11959]
-
-Thu Jan  7 11:34:14 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* include/ruby/backward.h (ruby_show_copyright_to_die): for source
-	  code backward compatibility.
-
-	* ruby.c (process_options): return Qtrue to exit the process
-	  successfully.
-
-	* version.c (ruby_show_copyright): no longer exit.
-
-Wed Jan  6 17:22:53 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/optparse.rb (OptionParser#order!): add `into` optional
-	  keyword argument to store the results.  [Feature #11191]
-
-Tue Jan  5 21:44:37 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* ChangeLog: fix wrong class name.
-
-Tue Jan  5 21:43:50 2016  Kuniaki IGARASHI  <igaiga@gmail.com>
-
-	* test/ruby/test_string.rb(test_chr): added test for String#chr
-	  [fix GH-1179]
-
-Tue Jan  5 21:32:26 2016  Kuniaki IGARASHI  <igaiga@gmail.com>
-
-	* test/ruby/test_numeric.rb (test_nonzero_p): added test for Numeric#nonzero?
-	  [fix GH-1187]
-
-Tue Jan  5 11:47:23 2016  Damir Gaynetdinov  <damir.gaynetdinov@gmail.com>
-
-	* doc/marshal.rdoc: Clarify object references example, that the
-	  reference is same object.  [Fix GH-1156]
-
-Tue Jan  5 05:06:51 2016  Eric Wong  <e@80x24.org>
-
-	* ext/stringio/stringio.c (strio_binmode): implement to set encoding
-	* test/stringio/test_stringio.rb (test_binmode): new test
-	  [ruby-core:72699] [Bug #11945]
-
-Mon Jan  4 15:44:37 2016  Sho Hashimoto  <sho-h@ruby-lang.org>
-
-	* variable.c (rb_mod_deprecate_constant): [DOC] added
-	  documentation for Module#deprecate_constant. [ci skip]
-
-Mon Jan  4 15:36:38 2016  Sho Hashimoto  <sho-h@ruby-lang.org>
-
-	* thread_sync.c: [DOC] remove SizedQueue#close argument.
-	  [ci skip]
-
-Mon Jan  4 10:14:24 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* test/coverage/test_coverage.rb: ignored test when enabled to coverage.
-	  It lead to crash with `make test-all`.
-
-Mon Jan  4 08:10:44 2016  Yuichiro Kaneko  <yui-knk@ruby-lang.org>
-
-	* insns.def (opt_case_dispatch): Move a comment to the
-	  appropriate position.
-	  [ci skip]
-
-Sun Jan  3 23:55:13 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/rubygems/security.rb (DIGEST_ALGORITHM, KEY_ALGORITHM):
-	  should check same name as the used constants.
-	  [ruby-core:72674] [Bug #11940]
-
-Sun Jan  3 19:22:01 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* aclocal.m4: add fallback file for non-aclocal environments.
-	  [ruby-core:72683] [Bug #11942]
-
-Sun Jan  3 13:56:49 2016  Yuichiro Kaneko  <yui-knk@ruby-lang.org>
-
-	* eval_error.c (rb_print_undef): Use `rb_method_visibility_t`
-	  instead of `int`.
-	* eval_intern.h (rb_print_undef): ditto
-	* proc.c (mnew_internal): ditto
-	* vm_method.c (rb_export_method): ditto
-	  [Misc #11649] [ruby-core:71311] [fix GH-1078]
-
-Sun Jan  3 12:12:09 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* acinclude.m4: rename aclocal.m4, which should be generated by
-	  aclocal.  [ruby-core:72675] [Bug #11941]
-
-Sat Jan  2 21:07:55 2016  Eric Wong  <e@80x24.org>
-
-	* thread_sync.c (queue_do_pop): avoid cast with Qfalse
-	  (rb_szqueue_push): ditto, use queue_sleep wrapper
-
-Sat Jan  2 16:16:14 2016  Masatoshi SEKI  <m_seki@mva.biglobe.ne.jp>
-
-	* lib/erb.rb: Allow ERB subclass to add token easily.
-	  [Feature #11936]
-
-	* test/erb/test_erb.rb: ditto.
-
-Sat Jan  2 14:44:31 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* parse.y (regexp): set_yylval_num sets u1, should use nd_tag
-	  instead of nd_state.  [ruby-core:72638] [Bug #11932]
-
-Sat Jan  2 02:27:22 2016  Marc-Andre Lafortune  <ruby-core@marc-andre.ca>
-
-	* lib/ostruct.rb: Fix case of frozen object with initializer.
-	  Bug revealed by RubySpec [ruby-core:72639]
-
-Fri Jan  1 22:01:52 2016  Kazuhiro NISHIYAMA  <zn@mbf.nifty.com>
-
-	* NEWS: mention CSV's liberal_parsing option.
-
-Fri Jan  1 19:38:23 2016  okkez  <okkez000@gmail.com>
-
-	* doc/NEWS-2.3.0: fix double words typo.
-	  [ci skip][fix GH-1183]
-
-Fri Jan  1 15:28:56 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* compile.c (remove_unreachable_chunk): decrease count of
-	  call_info in removed instructions.  fix up r53402.
-
-Fri Jan  1 12:05:53 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* compile.c (remove_unreachable_chunk): remove unreferred label
-	  to optimize away unreachable chunk.
-
-Fri Jan  1 11:42:57 2016  James Edward Gray II  <james@graysoftinc.com>
-
-	* lib/csv.rb (CSV): Add a liberal_parsing option.
-	  Patch by Braden Anderson. [#11839]
-	* test/csv/test_features.rb:  test liberal_parsing
-
-Fri Jan  1 10:27:28 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* tool/mkconfig.rb (RbConfig): prefix SDKROOT to oldincludedir
-	  not includedir, the latter is outside the ruby installation.
-	  [ruby-core:72496] [Bug #11881]
-
-Fri Jan  1 08:53:02 2016  Yuki Kurihara  <co000ri@gmail.com>
-
-	* test/ruby/test_lazy_enumerator.rb (test_take_bad_arg): Add test
-	  code in case of Enumerator::Lazy#take called with negative number.
-	  [ruby-dev:49467] [Bug #11933]
-
-Fri Jan  1 05:06:20 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* parse.y (parser_here_document): update indent for each line in
-	  indented here document with single-quotes.
-	  [ruby-core:72479] [Bug #11871]
-
-Fri Jan  1 03:26:44 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/ostruct.rb (freeze): define deferred accessors before
-	  freezing to get rid of an error when just reading frozen
-	  OpenStruct.
-
-Thu Dec 31 14:36:45 2015  Marc-Andre Lafortune  <ruby-core@marc-andre.ca>
-
-	* lib/ostruct.rb: Fix new_ostruct_member to correctly avoid
-	  redefinition [#11901]
-
-Thu Dec 31 02:45:12 2015  NARUSE, Yui  <naruse@ruby-lang.org>
-
-	* test/ruby/test_module.rb (test_classpath): r53376 may change
-	  the order of m.constants.
-	  `make TESTS='-v ruby/test_class.rb ruby/test_module.rb' test-all`
-	  may fail after that.
-	  http://rubyci.s3.amazonaws.com/tk2-243-31075/ruby-trunk/log/20151230T164202Z.log.html.gz
-
-Thu Dec 31 02:20:00 2015  Benoit Daloze  <eregontp@gmail.com>
-
-	* common.mk (help): Fix typo.
-
-Wed Dec 30 20:53:09 2015  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/net/http/responses.rb: Added new response class for 451 status code.
-	* lib/net/http.rb: documentation for HTTPUnavailableForLegalReasons
-
-Wed Dec 30 20:45:45 2015  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* lib/webrick/httpstatus.rb: Added HTTP 451 Status Code.
-	  [fix GH-1167] Patch by @MuhammetDilmac
-	  https://tools.ietf.org/html/draft-tbray-http-legally-restricted-status-00
-
-Wed Dec 30 20:25:52 2015  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* doc/syntax/calling_methods.rdoc: fix old operator for safe navigation
-	  operator. [ci skip][fix GH-1182] Patch by @dougo
-
-Wed Dec 30 16:43:23 2015  Kuniaki IGARASHI  <igaiga@gmail.com>
-
-	* test/ruby/test_string.rb (test_ord): Add test for String#ord.
-	  [Fix GH-1181]
-
-Wed Dec 30 11:28:57 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/forwardable.rb (def_instance_delegator): adjust backtrace of
-	  method body by tail call optimization.  adjusting the delegated
-	  target is still done by deleting backtrace.
-
-	* lib/forwardable.rb (def_single_delegator): ditto.
-
-Wed Dec 30 11:18:42 2015  Elliot Winkler  <elliot.winkler@gmail.com>
-
-	* lib/forwardable.rb (def_instance_delegator) fix delegating to
-	  'args' and 'block', clashing with local variables in generated
-	  methods.  [ruby-core:72579] [Bug #11916]
-
-	* lib/forwardable.rb (def_single_delegator): ditto.
-
-Wed Dec 30 09:58:56 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* object.c (rb_class_inherited_p): search the corresponding
-	  ancestor to prepended module from prepending class itself.
-	  [ruby-core:72493] [Bug #11878]
-
-Wed Dec 30 09:20:00 2015  Yuki Kurihara  <co000ri@gmail.com>
-
-	* test/stringio/test_io.rb (test_flag): add assertion for error when
-	  text and binary mode are mixed.
-	  [ruby-dev:49465] [Feature #11921]
-
-Wed Dec 30 08:43:59 2015  Yuki Kurihara  <co000ri@gmail.com>
-
-	* test/stringio/test_stringio.rb (test_initialize): add test for
-	  StringIO#initialize.  [ruby-core:72585] [Feature #11920]
-
-Wed Dec 30 05:19:24 2015  Eric Wong  <e@80x24.org>
-
-	* class.c (struct clone_const_arg): adjust for id_table
-	  (clone_const): ditto
-	  (clone_const_i): ditto
-	  (rb_mod_init_copy): ditto
-	  (rb_singleton_class_clone_and_attach): ditto
-	  (rb_include_class_new): ditto
-	  (include_modules_at): ditto
-	* constant.h (rb_free_const_table): ditto
-	* gc.c (free_const_entry_i): ditto
-	  (rb_free_const_table): ditto
-	  (obj_memsize_of): ditto
-	  (mark_const_entry_i): ditto
-	  (mark_const_tbl): ditto
-	* internal.h (struct rb_classext_struct): ditto
-	* object.c (rb_mod_const_set): resolve class name on assignment
-	* variable.c (const_update): replace with const_tbl_update
-	  (const_tbl_update): new function
-	  (fc_i): adjust for id_table
-	  (find_class_path): ditto
-	  (autoload_const_set): st_update => const_tbl_update
-	  (rb_const_remove): adjust for id_table
-	  (sv_i): ditto
-	  (rb_local_constants_i): ditto
-	  (rb_local_constants): ditto
-	  (rb_mod_const_at): ditto
-	  (rb_mod_const_set): ditto
-	  (rb_const_lookup): ditto
-	  [ruby-core:72112] [Feature #11614]
-
-Wed Dec 30 04:10:13 2015  CHIKANAGA Tomoyuki  <nagachika@ruby-lang.org>
-
-	* thread_pthread.c (rb_thread_create_timer_thread): destroy attr even
-	  if pthread_create() failed.
-
-Wed Dec 30 02:55:09 2015  Eric Wong  <e@80x24.org>
-
-	* thread_pthread.c (setup_communication_pipe): delay setting owner
-	  (rb_thread_create_timer_thread): until thread creation succeeds
-	  [ruby-core:72590] [Bug #11922]
-
-Tue Dec 29 19:12:46 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* ruby.c (proc_options): -W command line option should be able to
-	  override -w in RUBYOPT environment variable.
-
-Tue Dec 29 17:54:16 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* eval.c (ignored_block): warn if a block is given to `using`,
-	  which is probably for `Module.new`.
-
-Tue Dec 29 12:48:34 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* lib/ostruct.rb (OpenStruct): make respond_to? working on
-	  just-allocated objects for workaround of Psych.
-	  [ruby-core:72501] [Bug #11884]
-
-Tue Dec 29 10:35:00 2015  Kenta Murata  <mrkn@mrkn.jp>
-
-	* test/mkmf/test_have_func.rb (test_have_func):
-	  Add assertion to examine the existence of HAVE_RUBY_INIT.
-
-	* test/mkmf/test_have_func.rb (test_not_have_func):
-	  Add assertion to examine the absence of HAVE_RUBY_INIT.
-
-Tue Dec 29 06:50:42 2015  Eric Wong  <e@80x24.org>
-
-	* thread_sync.c: static classes
-
-Tue Dec 29 05:30:30 2015  Eric Wong  <e@80x24.org>
-
-	* lib/resolv.rb (Resolv::IPv6.create): avoid modifying frozen
-	* test/resolv/test_dns.rb (test_ipv6_create): test for above
-	  [Bug #11910] [ruby-core:72559]
-
-Mon Dec 28 14:55:57 2015  Kuniaki IGARASHI  <igaiga@gmail.com>
-
-	* test/ruby/test_string.rb (TestString#test_rstrip_bang): Add test
-	  for String#rstrip!.  [Fix GH-1176]
-
-Mon Dec 28 09:18:53 2015  Kuniaki IGARASHI  <igaiga@gmail.com>
-
-	* test/ruby/test_string.rb (TestString#test_lstrip_bang): Add test
-	  for String#lstrip!.  [Fix GH-1176]
-
-Sun Dec 27 23:32:26 2015  Masaki Suketa <masaki.suketa@nifty.ne.jp>
-
-	* ext/win32ole/win32ole.c (ole_variant2val): refactoring.
-
-Sun Dec 27 21:14:42 2015  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* process.c (rb_execarg_parent_start1): need to convert the encoding to
-	  ospath's one.
-
-Sun Dec 27 20:54:22 2015  NAKAMURA Usaku  <usa@ruby-lang.org>
-
-	* process.c: use rb_w32_uchdir() instead of plain chdir() on Windows.
-	  reported by naruse via twitter.
-
-	* process.c (rb_execarg_addopt): need to convert the encoding to
-	  ospath's one.
-
-Sun Dec 27 20:00:31 2015  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* enc/x_emoji.h: fix dead-link.
-
-Sun Dec 27 19:55:55 2015  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
-
-	* doc/NEWS-2.3.0: fix a typo.
-
-Sun Dec 27 18:08:15 2015  Kuniaki IGARASHI  <igaiga@gmail.com>
-
-	* string.c (rb_str_lstrip_bang, rb_str_rstrip_bang): [DOC] Fix
-	  ruby-doc comments for String#rstrip! and lstrip!.  It looks like
-	  dropped bang.  [Fix GH-1175]
-
-Sun Dec 27 15:14:20 2015  Eric Wong  <e@80x24.org>
-
-	* io.c (io_getpartial): remove unused kwarg from template
-	* test/ruby/test_io.rb (test_readpartial_bad_args): new
-	  [Bug #11885]
-
-Sun Dec 27 11:50:53 2015  Kuniaki IGARASHI  <igaiga@gmail.com>
-
-	* test/ruby/test_string.rb (test_rstrip, test_lstrip): Add tests
-	  for String#lstrip and rstrip.  The test cases are used from
-	  string.c ruby-doc comments.  [Fix GH-1174]
-
-Sun Dec 27 11:47:46 2015  Kuniaki IGARASHI  <igaiga@gmail.com>
-
-	* test/ruby/test_string.rb (test_insert): Add test for
-	  String#insert.  The test cases are written in string.c
-	  comments as a reference.  [Fix GH-1173]
-
-Sun Dec 27 11:03:33 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* parse.y (show_bitstack): trace stack_type value if yydebug.
-
-Sun Dec 27 10:03:14 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* enc/depend (enc, trans): fix version dependency, shared object
-	  files depend on the RUBY_SO_NAME value for runtime link.
-
-Sun Dec 27 09:47:20 2015  Masaki Suketa <masaki.suketa@nifty.ne.jp>
-
-	* ext/win32ole/win32ole.c (ole_vstr2wc, ole_variant2val): fix blank
-	  string conversion.
-	  [Bug #11880]
-	  Thanks Akio Tajima for the patch!
-
-Sun Dec 27 09:34:53 2015  craft4coder  <yooobuntu@163.com>
-
-	* doc/extension.rdoc: [DOC] `nul` should be uppercase.
-	  change 'nul' => 'NUL'.  [Fix GH-1172]
-
-Sat Dec 26 18:29:01 2015  Kouhei Sutou  <kou@cozmixng.org>
-
-	* lib/xmlrpc/client.rb: Support SSL options in async methods of
-	  XMLRPC::Client.
-	  [Bug #11489]
-	  Reported by Aleksandar Kostadinov. Thanks!!!
-
-Sat Dec 26 11:26:38 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* miniinit.c (Init_enc): add some common aliases of built-in
-	  encodings.  [ruby-core:72481] [Bug #11872]
-
-Fri Dec 25 22:43:26 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
-
-	* configure.in: extract RUBY_RELEASE_DAY at generating Makefile.
-
-	* version.h (RUBY_RELEASE_DATE): construct from RUBY_RELEASE_YEAR,
-	  RUBY_RELEASE_MONTH, and RUBY_RELEASE_DAY.
-
-Fri Dec 25 21:33:06 2015  Yukihiro Matsumoto  <matz@ruby-lang.org>
-
-	* version.h (RUBY_VERSION): 2.4.0 development has started.
-
-Fri Dec 25 14:12:12 2015  Martin Duerst  <duerst@it.aoyama.ac.jp>
-
-	* doc/ChangeLog-2.3.0, ext/tk/lib/tkextlib/SUPPORT_STATUS,
-	  include/ruby/version.h: minor grammar fixes [ci skip]
-
-Fri Dec 25 08:23:22 2015  Tadashi Saito  <tad.a.digger@gmail.com>
-
-	* compile.c, cont.c, doc, man: fix common misspelling.
-	  [ruby-core:72466] [Bug #11870]
-
-
-For the changes before 2.3.0, see doc/ChangeLog-2.3.0
-For the changes before 2.2.0, see doc/ChangeLog-2.2.0
-For the changes before 2.1.0, see doc/ChangeLog-2.1.0
-For the changes before 2.0.0, see doc/ChangeLog-2.0.0
-For the changes before 1.9.3, see doc/ChangeLog-1.9.3
-For the changes before 1.8.0, see doc/ChangeLog-1.8.0
-
-Local variables:
-coding: us-ascii
-add-log-time-format: (lambda ()
-  (let* ((time (current-time))
-	 (system-time-locale "C")
-	 (diff (+ (cadr time) 32400))
-	 (lo (% diff 65536))
-	 (hi (+ (car time) (/ diff 65536))))
-  (format-time-string "%a %b %e %H:%M:%S %Y" (list hi lo) t)))
-indent-tabs-mode: t
-tab-width: 8
-change-log-indent-text: 2
-end:
-vim: tabstop=8 shiftwidth=2
diff --git a/LEGAL b/LEGAL
index ef4acefaa5..0423d57ac9 100644
--- a/LEGAL
+++ b/LEGAL
@@ -1,145 +1,331 @@
-LEGAL NOTICE INFORMATION
-------------------------
+# -*- rdoc -*-
+
+= LEGAL NOTICE INFORMATION
+--------------------------
 
 All the files in this distribution are covered under either the Ruby's
 license (see the file COPYING) or public-domain except some files
 mentioned below.
 
-ccan/build_assert/build_assert.h
-ccan/check_type/check_type.h
-ccan/container_of/container_of.h
-ccan/str/str.h
+[addr2line.c]
 
-  These files are licensed under the CC0.
+  A part of this file is from FreeBSD.
 
-    http://creativecommons.org/choose/zero/
+  >>>
+    Copyright (c) 1986, 1988, 1991, 1993::
+    The Regents of the University of California.  All rights reserved.
 
-ccan/list/list.h
+    (c) UNIX System Laboratories, Inc.
 
-  This file is licensed under the MIT License.
+    All or some portions of this file are derived from material licensed
+    to the University of California by American Telephone and Telegraph
+    Co. or Unix System Laboratories, Inc. and are reproduced herein with
+    the permission of UNIX System Laboratories, Inc.
 
-    Permission is hereby granted, free of charge, to any person obtaining a copy
-    of this software and associated documentation files (the "Software"), to deal
-    in the Software without restriction, including without limitation the rights
-    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-    copies of the Software, and to permit persons to whom the Software is
-    furnished to do so, subject to the following conditions:
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions
+    are met:
+    1. Redistributions of source code must retain the above copyright
+       notice, this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright
+       notice, this list of conditions and the following disclaimer in the
+       documentation and/or other materials provided with the distribution.
+    4. Neither the name of the University nor the names of its contributors
+       may be used to endorse or promote products derived from this software
+       without specific prior written permission.
 
-    The above copyright notice and this permission notice shall be included in
-    all copies or substantial portions of the Software.
+    THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+    ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+    ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+    FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+    DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+    OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+    HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+    OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+    SUCH DAMAGE.
 
-    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-    THE SOFTWARE.
-
-include/ruby/oniguruma.h:
-regcomp.c:
-regenc.[ch]:
-regerror.c:
-regexec.c:
-regint.h:
-regparse.[ch]:
-enc/ascii.c
-enc/big5.c
-enc/cp949.c
-enc/emacs_mule.c
-enc/encdb.c
-enc/euc_jp.c
-enc/euc_kr.c
-enc/euc_tw.c
-enc/gb18030.c
-enc/gb2312.c
-enc/gbk.c
-enc/iso_8859_1.c
-enc/iso_8859_10.c
-enc/iso_8859_11.c
-enc/iso_8859_13.c
-enc/iso_8859_14.c
-enc/iso_8859_15.c
-enc/iso_8859_16.c
-enc/iso_8859_2.c
-enc/iso_8859_3.c
-enc/iso_8859_4.c
-enc/iso_8859_5.c
-enc/iso_8859_6.c
-enc/iso_8859_7.c
-enc/iso_8859_8.c
-enc/iso_8859_9.c
-enc/koi8_r.c
-enc/koi8_u.c
-enc/shift_jis.c
-enc/unicode.c
-enc/us_ascii.c
-enc/utf_16be.c
-enc/utf_16le.c
-enc/utf_32be.c
-enc/utf_32le.c
-enc/utf_8.c
-enc/windows_1251.c
-
-Oniguruma  ----   (C) K.Kosako <sndgk393 AT ybb DOT ne DOT jp>
-
-http://www.geocities.jp/kosako3/oniguruma/
-http://www.ruby-lang.org/cgi-bin/cvsweb.cgi/oniguruma/
-http://www.freebsd.org/cgi/cvsweb.cgi/ports/devel/oniguruma/
-
-   When this software is partly used or it is distributed with Ruby,
-   this of Ruby follows the license of Ruby.
-
-enc/trans/JIS/JISX0201-KANA%UCS.src:
-enc/trans/JIS/JISX0208@1990%UCS.src:
-enc/trans/JIS/JISX0212%UCS.src:
-enc/trans/JIS/UCS%JISX0201-KANA.src:
-enc/trans/JIS/UCS%JISX0208@1990.src:
-enc/trans/JIS/UCS%JISX0212.src:
+	@(#)subr_prf.c	8.3 (Berkeley) 1/21/94
+
+
+[ccan/build_assert/build_assert.h]
+[ccan/check_type/check_type.h]
+[ccan/container_of/container_of.h]
+[ccan/str/str.h]
+
+  These files are licensed under the {CC0}[https://creativecommons.org/choose/zero/].
+
+[ccan/list/list.h]
+
+  This file is licensed under the {MIT License}[rdoc-label:label-MIT+License].
+
+[coroutine]
+
+  Unless otherwise specified, these files are licensed under the
+  {MIT License}[rdoc-label:label-MIT+License].
+
+[include/ruby/onigmo.h]
+[include/ruby/oniguruma.h]
+[regcomp.c]
+[regenc.c]
+[regenc.h]
+[regerror.c]
+[regexec.c]
+[regint.h]
+[regparse.c]
+[regparse.h]
+[enc/ascii.c]
+[enc/big5.c]
+[enc/cp949.c]
+[enc/emacs_mule.c]
+[enc/encdb.c]
+[enc/euc_jp.c]
+[enc/euc_kr.c]
+[enc/euc_tw.c]
+[enc/gb18030.c]
+[enc/gb2312.c]
+[enc/gbk.c]
+[enc/iso_8859_1.c]
+[enc/iso_8859_10.c]
+[enc/iso_8859_11.c]
+[enc/iso_8859_13.c]
+[enc/iso_8859_14.c]
+[enc/iso_8859_15.c]
+[enc/iso_8859_16.c]
+[enc/iso_8859_2.c]
+[enc/iso_8859_3.c]
+[enc/iso_8859_4.c]
+[enc/iso_8859_5.c]
+[enc/iso_8859_6.c]
+[enc/iso_8859_7.c]
+[enc/iso_8859_8.c]
+[enc/iso_8859_9.c]
+[enc/koi8_r.c]
+[enc/koi8_u.c]
+[enc/shift_jis.c]
+[enc/unicode.c]
+[enc/us_ascii.c]
+[enc/utf_16be.c]
+[enc/utf_16le.c]
+[enc/utf_32be.c]
+[enc/utf_32le.c]
+[enc/utf_8.c]
+[enc/windows_1251.c]
+[enc/windows_31j.c]
+
+  Onigmo (Oniguruma-mod) LICENSE
+
+  >>>
+    Copyright (c) 2002-2009::  K.Kosako  <sndgk393 AT ybb DOT ne DOT jp>
+    Copyright (c) 2011-2014::  K.Takata  <kentkt AT csc DOT jp>
+    All rights reserved.
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions
+    are met:
+    1. Redistributions of source code must retain the above copyright
+       notice, this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright
+       notice, this list of conditions and the following disclaimer in the
+       documentation and/or other materials provided with the distribution.
 
+    THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+    ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+    ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+    FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+    DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+    OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+    HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+    OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+    SUCH DAMAGE.
+
+  Oniguruma LICENSE
+
+  >>>
+    Copyright (c) 2002-2009::  K.Kosako  <sndgk393 AT ybb DOT ne DOT jp>
+    All rights reserved.
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions
+    are met:
+    1. Redistributions of source code must retain the above copyright
+       notice, this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright
+       notice, this list of conditions and the following disclaimer in the
+       documentation and/or other materials provided with the distribution.
+
+    THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+    ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+    ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+    FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+    DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+    OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+    HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+    OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+    SUCH DAMAGE.
+
+  * https://github.com/k-takata/Onigmo/
+  * https://github.com/kkos/oniguruma
+  * https://svnweb.freebsd.org/ports/head/devel/oniguruma/
+
+    When this software is partly used or it is distributed with Ruby,
+    this of Ruby follows the license of Ruby.
+
+[enc/windows_1250.c]
+[enc/windows_1252.c]
+
+  >>>
+    Copyright (c) 2006-2007::  Byte      <byte AT mail DOT kna DOT ru>
+                               K.Kosako  <sndgk393 AT ybb DOT ne DOT jp>
+    All rights reserved.
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions
+    are met:
+    1. Redistributions of source code must retain the above copyright
+       notice, this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright
+       notice, this list of conditions and the following disclaimer in the
+       documentation and/or other materials provided with the distribution.
+
+    THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+    ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+    ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+    FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+    DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+    OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+    HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+    OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+    SUCH DAMAGE.
+
+[enc/cesu_8.c]
+[enc/windows_1253.c]
+[enc/windows_1254.c]
+[enc/windows_1257.c]
+
+  >>>
+    Copyright (c) 2002-2007::  K.Kosako  <sndgk393 AT ybb DOT ne DOT jp>
+    All rights reserved.
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions
+    are met:
+    1. Redistributions of source code must retain the above copyright
+       notice, this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright
+       notice, this list of conditions and the following disclaimer in the
+       documentation and/or other materials provided with the distribution.
+
+    THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+    ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+    ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+    FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+    DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+    OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+    HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+    OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+    SUCH DAMAGE.
+
+[enc/trans/GB/GB12345%UCS.src]
+[enc/trans/GB/UCS%GB12345.src]
+[enc/trans/GB/GB2312%UCS.src]
+[enc/trans/GB/UCS%GB2312.src]
+
+  These files have this explanatory texts.
+
+  >>>
+    This mapping data was created from files provided by Unicode, Inc.
+    (The Unicode Consortium). The files were used to create a product supporting
+    Unicode, as explicitly permitted in the files' copyright notices.
+    Please note that Unicode, Inc. never made any claims as to fitness of these
+    files for any particular purpose, and has ceased to publish the files many
+    years ago.
+
+[enc/trans/JIS/JISX0201-KANA%UCS.src]
+[enc/trans/JIS/JISX0208\@1990%UCS.src]
+[enc/trans/JIS/JISX0212%UCS.src]
+[enc/trans/JIS/UCS%JISX0201-KANA.src]
+[enc/trans/JIS/UCS%JISX0208@1990.src]
+[enc/trans/JIS/UCS%JISX0212.src]
+
+  These files are copyrighted as the following.
+
+  >>>
     © 2015 Unicode®, Inc.
+
     For terms of use, see http://www.unicode.org/terms_of_use.html
 
-enc/trans/JIS/JISX0213-1%UCS@BMP.src:
-enc/trans/JIS/JISX0213-1%UCS@SIP.src:
-enc/trans/JIS/JISX0213-2%UCS@BMP.src:
-enc/trans/JIS/JISX0213-2%UCS@SIP.src:
+[enc/trans/JIS/JISX0213-1%UCS@BMP.src]
+[enc/trans/JIS/JISX0213-1%UCS@SIP.src]
+[enc/trans/JIS/JISX0213-2%UCS@BMP.src]
+[enc/trans/JIS/JISX0213-2%UCS@SIP.src]
+
+  These files are copyrighted as the following.
+
+  >>>
+    Copyright (C) 2001:: earthian@tama.or.jp, All Rights Reserved.
+    Copyright (C) 2001:: I'O, All Rights Reserved.
+    Copyright (C) 2006:: Project X0213, All Rights Reserved.
+    You can use, modify, distribute this table freely.
+
+[enc/trans/JIS/UCS@BMP%JISX0213-1.src]
+[enc/trans/JIS/UCS@BMP%JISX0213-2.src]
+[enc/trans/JIS/UCS@SIP%JISX0213-1.src]
+[enc/trans/JIS/UCS@SIP%JISX0213-2.src]
+
+  These files are copyrighted as the following.
 
- 	Copyright (C) 2001 earthian@tama.or.jp, All Rights Reserved.
- 	Copyright (C) 2001 I'O, All Rights Reserved.
- 	Copyright (C) 2006 Project X0213, All Rights Reserved.
- 	You can use, modify, distribute this table freely.
+  >>>
+    Copyright (C) 2001:: earthian@tama.or.jp, All Rights Reserved.
+    Copyright (C) 2001:: I'O, All Rights Reserved.
+    You can use, modify, distribute this table freely.
 
-enc/trans/JIS/UCS@BMP%JISX0213-1.src:
-enc/trans/JIS/UCS@BMP%JISX0213-2.src:
-enc/trans/JIS/UCS@SIP%JISX0213-1.src:
-enc/trans/JIS/UCS@SIP%JISX0213-2.src:
+[enc/trans/ucm/glibc-BIG5-2.3.3.ucm]
+[enc/trans/ucm/glibc-BIG5HKSCS-2.3.3.ucm]
 
- 	Copyright (C) 2001 earthian@tama.or.jp, All Rights Reserved.
- 	Copyright (C) 2001 I'O, All Rights Reserved.
- 	You can use, modify, distribute this table freely.
+  >>>
+    Copyright (C) 2001-2005:: International Business Machines
+                              Corporation and others.  All Rights Reserved.
 
-configure:
+[enc/trans/ucm/windows-950-2000.ucm]
+[enc/trans/ucm/windows-950_hkscs-2001.ucm]
+
+  >>>
+    Copyright (C) 2001-2002:: International Business Machines
+                              Corporation and others.  All Rights Reserved.
+
+
+[configure]
 
   This file is free software.
 
-    Copyright (C) 1992, 93, 94, 95, 96 Free Software Foundation, Inc.
+  >>>
+    Copyright (C) 1992-1996, 1998-2012:: Free Software Foundation, Inc.
 
     This configure script is free software; the Free Software Foundation
     gives unlimited permission to copy, distribute and modify it.
 
-tool/config.guess:
-tool/config.sub:
+[tool/config.guess]
+[tool/config.sub]
 
   As long as you distribute these files with the file configure, they
   are covered under the Ruby's license.
 
-      Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999
-      Free Software Foundation, Inc.
+  >>>
+    Copyright 1992-2018:: Free Software Foundation, Inc.
 
     This file is free software; you can redistribute it and/or modify it
     under the terms of the GNU General Public License as published by
-    the Free Software Foundation; either version 2 of the License, or
+    the Free Software Foundation; either version 3 of the License, or
     (at your option) any later version.
 
     This program is distributed in the hope that it will be useful, but
@@ -148,54 +334,85 @@ tool/config.sub:
     General Public License for more details.
 
     You should have received a copy of the GNU General Public License
-    along with this program; if not, write to the Free Software
-    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+    along with this program; if not, see <https://www.gnu.org/licenses/>.
 
     As a special exception to the GNU General Public License, if you
     distribute this file as part of a program that contains a
     configuration script generated by Autoconf, you may include it under
-    the same distribution terms that you use for the rest of that program.
-
-parse.c:
-
-  This file is licensed under the GPL, but is incorporated into Ruby and
+    the same distribution terms that you use for the rest of that
+    program.  This Exception is an additional permission under section 7
+    of the GNU General Public License, version 3 ("GPLv3").
+
+[tool/lib/test/*]
+[tool/lib/core_assertions.rb]
+
+  Some of methods on these files are based on MiniTest 4. MiniTest 4 is
+  distributed under the MIT License.
+
+  >>>
+    Copyright (c) Ryan Davis, seattle.rb
+
+    Permission is hereby granted, free of charge, to any person obtaining
+    a copy of this software and associated documentation files (the
+    'Software'), to deal in the Software without restriction, including
+    without limitation the rights to use, copy, modify, merge, publish,
+    distribute, sublicense, and/or sell copies of the Software, and to
+    permit persons to whom the Software is furnished to do so, subject to
+    the following conditions:
+
+    The above copyright notice and this permission notice shall be
+    included in all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND,
+    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+    CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+    TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+    SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+[parse.c]
+[parse.h]
+
+  These files are licensed under the GPL, but are incorporated into Ruby and
   redistributed under the terms of the Ruby license, as permitted by the
   exception to the GPL below.
 
-     Copyright (C) 1984, 1989, 1990, 2000, 2001, 2002, 2003, 2004, 2005, 2006
-     Free Software Foundation, Inc.
+  >>>
+    Copyright (C) 1984, 1989-1990, 2000-2015, 2018:: Free Software Foundation, Inc.
 
-     This program is free software; you can redistribute it and/or modify
-     it under the terms of the GNU General Public License as published by
-     the Free Software Foundation; either version 2, or (at your option)
-     any later version.
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
 
-     This program is distributed in the hope that it will be useful,
-     but WITHOUT ANY WARRANTY; without even the implied warranty of
-     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-     GNU General Public License for more details.
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
 
-     You should have received a copy of the GNU General Public License
-     along with this program; if not, write to the Free Software
-     Foundation, Inc., 51 Franklin Street, Fifth Floor,
-     Boston, MA 02110-1301, USA.  */
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+    As a special exception, you may create a larger work that contains
+    part or all of the Bison parser skeleton and distribute that work
+    under terms of your choice, so long as that work isn't itself a
+    parser generator using the skeleton or a modified version thereof
+    as a parser skeleton.  Alternatively, if you modify or redistribute
+    the parser skeleton itself, you may (at your option) remove this
+    special exception, which will cause the skeleton and the resulting
+    Bison output files to be licensed under the GNU General Public
+    License without this special exception.
 
-  /* As a special exception, you may create a larger work that contains
-     part or all of the Bison parser skeleton and distribute that work
-     under terms of your choice, so long as that work isn't itself a
-     parser generator using the skeleton or a modified version thereof
-     as a parser skeleton.  Alternatively, if you modify or redistribute
-     the parser skeleton itself, you may (at your option) remove this
-     special exception, which will cause the skeleton and the resulting
-     Bison output files to be licensed under the GNU General Public
-     License without this special exception.
+    This special exception was added by the Free Software Foundation in
+    version 2.2 of Bison.
 
-     This special exception was added by the Free Software Foundation in
-     version 2.2 of Bison.  */
+[missing/dtoa.c]
 
-util.c (partly):
+  This file is under these licenses.
 
-    Copyright (c) 1991, 2000, 2001 by Lucent Technologies.
+  >>>
+    Copyright (c) 1991, 2000, 2001:: by Lucent Technologies.
 
     Permission to use, copy, modify, and distribute this software for any
     purpose without fee is hereby granted, provided that this entire notice
@@ -208,71 +425,74 @@ util.c (partly):
     REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
     OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
 
-win32/win32.[ch]:
+  >>>
+    Copyright (c) 2004-2008:: David Schultz <das@FreeBSD.ORG>
+                              All rights reserved.
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions
+    are met:
+    1. Redistributions of source code must retain the above copyright
+       notice, this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright
+       notice, this list of conditions and the following disclaimer in the
+       documentation and/or other materials provided with the distribution.
+
+    THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+    ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+    ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+    FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+    DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+    OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+    HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+    OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+    SUCH DAMAGE.
+
+[win32/win32.c]
+[include/ruby/win32.h]
 
   You can apply the Artistic License to these files. (or GPL,
   alternatively)
 
-    Copyright (c) 1993, Intergraph Corporation
+  >>>
+    Copyright (c) 1993:: Intergraph Corporation
 
     You may distribute under the terms of either the GNU General Public
     License or the Artistic License, as specified in the perl README file.
 
-util.c (partly):
-
-   Copyright (c) 2004-2008 David Schultz <das@FreeBSD.ORG>
-   All rights reserved.
-
-   Redistribution and use in source and binary forms, with or without
-   modification, are permitted provided that the following conditions
-   are met:
-   1. Redistributions of source code must retain the above copyright
-      notice, this list of conditions and the following disclaimer.
-   2. Redistributions in binary form must reproduce the above copyright
-      notice, this list of conditions and the following disclaimer in the
-      documentation and/or other materials provided with the distribution.
-
-   THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
-   ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-   ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
-   FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
-   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
-   OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
-   HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
-   LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
-   OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
-   SUCH DAMAGE.
-
-random.c
+[missing/mt19937.c]
 
   This file is under the new-style BSD license.
 
-    A C-program for MT19937, with initialization improved 2002/2/10.
+  >>>
+    A C-program for MT19937, with initialization improved 2002/2/10.::
     Coded by Takuji Nishimura and Makoto Matsumoto.
+
     This is a faster version by taking Shawn Cokus's optimization,
     Matthe Bellew's simplification, Isaku Wada's real version.
 
     Before using, initialize the state by using init_genrand(seed)
     or init_by_array(init_key, key_length).
 
-    Copyright (C) 1997 - 2002, Makoto Matsumoto and Takuji Nishimura,
-    All rights reserved.
+    Copyright (C) 1997 - 2002:: Makoto Matsumoto and Takuji Nishimura,
+                                All rights reserved.
 
     Redistribution and use in source and binary forms, with or without
     modification, are permitted provided that the following conditions
     are met:
 
-      1. Redistributions of source code must retain the above copyright
-	 notice, this list of conditions and the following disclaimer.
+    1. Redistributions of source code must retain the above copyright
+       notice, this list of conditions and the following disclaimer.
 
-      2. Redistributions in binary form must reproduce the above copyright
-	 notice, this list of conditions and the following disclaimer in the
-	 documentation and/or other materials provided with the distribution.
+    2. Redistributions in binary form must reproduce the above copyright
+       notice, this list of conditions and the following disclaimer in the
+       documentation and/or other materials provided with the distribution.
 
-      3. The names of its contributors may not be used to endorse or promote
-	 products derived from this software without specific prior written
-	 permission.
+    3. The names of its contributors may not be used to endorse or promote
+       products derived from this software without specific prior written
+       permission.
 
     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
@@ -291,12 +511,15 @@ random.c
     http://www.math.keio.ac.jp/matumoto/emt.html
     email: matumoto@math.keio.ac.jp
 
-vm_dump.c:procstat_vm
+  The Wayback Machine url: http://web.archive.org/web/19990429082237/http://www.math.keio.ac.jp/matumoto/emt.html
+
+[missing/procstat_vm.c]
 
   This file is under the new-style BSD license.
 
-    Copyright (c) 2007 Robert N. M. Watson
-    All rights reserved.
+  >>>
+    Copyright (c) 2007:: Robert N. M. Watson
+                         All rights reserved.
 
     Redistribution and use in source and binary forms, with or without
     modification, are permitted provided that the following conditions
@@ -321,181 +544,98 @@ vm_dump.c:procstat_vm
 
     $FreeBSD: head/usr.bin/procstat/procstat_vm.c 261780 2014-02-11 21:57:37Z jhb $
 
-vsnprintf.c:
+[vsnprintf.c]
 
-  This file is under the old-style BSD license.  Note that the
-  paragraph 3 below is now null and void.
+  This file is under the {old-style BSD license}[rdoc-label:label-Old-style+BSD+license].
 
-    Copyright (c) 1990, 1993
-         The Regents of the University of California.  All rights reserved.
+  >>>
+    Copyright (c) 1990, 1993::
+    The Regents of the University of California.  All rights reserved.
 
     This code is derived from software contributed to Berkeley by
     Chris Torek.
 
-    Redistribution and use in source and binary forms, with or without
-    modification, are permitted provided that the following conditions
-    are met:
-    1. Redistributions of source code must retain the above copyright
-       notice, this list of conditions and the following disclaimer.
-    2. Redistributions in binary form must reproduce the above copyright
-       notice, this list of conditions and the following disclaimer in the
-       documentation and/or other materials provided with the distribution.
-    3. Neither the name of the University nor the names of its contributors
-       may be used to endorse or promote products derived from this software
-       without specific prior written permission.
-
-    THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
-    ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-    ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
-    FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
-    DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
-    OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
-    HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
-    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
-    OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
-    SUCH DAMAGE.
-
-    IMPORTANT NOTE:
-    --------------
-    From ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change
-    paragraph 3 above is now null and void.
-
-st.[ch]:
-missing/alloca.c:
-missing/dup2.c:
-missing/erf.c:
-missing/finite.c:
-missing/hypot.c:
-missing/isinf.c:
-missing/isnan.c:
-missing/lgamma_r.c:
-missing/memcmp.c:
-missing/memmove.c:
-missing/strchr.c:
-missing/strstr.c:
-missing/strtol.c:
-missing/tgamma.c:
-ext/digest/sha1/sha1.[ch]:
+[st.c]
+[strftime.c]
+[include/ruby/st.h]
+[missing/acosh.c]
+[missing/alloca.c]
+[missing/erf.c]
+[missing/hypot.c]
+[missing/lgamma_r.c]
+[missing/memcmp.c]
+[missing/memmove.c]
+[missing/strchr.c]
+[missing/strerror.c]
+[missing/strstr.c]
+[missing/tgamma.c]
+[ext/date/date_strftime.c]
+[ext/digest/sha1/sha1.c]
+[ext/digest/sha1/sha1.h]
 
   These files are all under public domain.
 
-missing/crypt.c:
+[missing/crypt.c]
 
-  This file is under the old-style BSD license.  Note that the
-  paragraph 3 below is now null and void.
+  This file is under the {old-style BSD license}[rdoc-label:label-Old-style+BSD+license].
 
-    Copyright (c) 1989, 1993
-    	The Regents of the University of California.  All rights reserved.
+  >>>
+    Copyright (c) 1989, 1993::
+    The Regents of the University of California.  All rights reserved.
 
     This code is derived from software contributed to Berkeley by
     Tom Truscott.
 
-    Redistribution and use in source and binary forms, with or without
-    modification, are permitted provided that the following conditions
-    are met:
-    1. Redistributions of source code must retain the above copyright
-       notice, this list of conditions and the following disclaimer.
-    2. Redistributions in binary form must reproduce the above copyright
-       notice, this list of conditions and the following disclaimer in the
-       documentation and/or other materials provided with the distribution.
-    3. Neither the name of the University nor the names of its contributors
-       may be used to endorse or promote products derived from this software
-       without specific prior written permission.
+[missing/setproctitle.c]
 
-    THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
-    ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-    ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
-    FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
-    DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
-    OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
-    HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
-    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
-    OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
-    SUCH DAMAGE.
+  This file is under the {old-style BSD license}[rdoc-label:label-Old-style+BSD+license].
 
-missing/setproctitle.c
+  >>>
+    Copyright 2003:: Damien Miller
+    Copyright (c) 1983, 1995-1997:: Eric P. Allman
+    Copyright (c) 1988, 1993::
+    The Regents of the University of California.  All rights reserved.
 
-  This file is under the old-style BSD license.  Note that the
-  paragraph 3 below is now null and void.
+[missing/strlcat.c]
+[missing/strlcpy.c]
 
-    Copyright 2003 Damien Miller
-    Copyright (c) 1983, 1995-1997 Eric P. Allman
-    Copyright (c) 1988, 1993
-    	The Regents of the University of California.  All rights reserved.
+  These files are under an ISC-style license.
 
-    Redistribution and use in source and binary forms, with or without
-    modification, are permitted provided that the following conditions
-    are met:
-    1. Redistributions of source code must retain the above copyright
-       notice, this list of conditions and the following disclaimer.
-    2. Redistributions in binary form must reproduce the above copyright
-       notice, this list of conditions and the following disclaimer in the
-       documentation and/or other materials provided with the distribution.
-    3. Neither the name of the University nor the names of its contributors
-       may be used to endorse or promote products derived from this software
-       without specific prior written permission.
-
-    THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
-    ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-    ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
-    FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
-    DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
-    OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
-    HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
-    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
-    OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
-    SUCH DAMAGE.
-
-missing/strlcat.c
-missing/strlcpy.c
-
-  These files are under the new-style BSD license.
-
-    Copyright (c) 1998 Todd C. Miller <Todd.Miller@courtesan.com>
-    All rights reserved.
+  >>>
+    Copyright (c) 1998, 2015:: Todd C. Miller <Todd.Miller@courtesan.com>
 
-    Redistribution and use in source and binary forms, with or without
-    modification, are permitted provided that the following conditions
-    are met:
-    1. Redistributions of source code must retain the above copyright
-       notice, this list of conditions and the following disclaimer.
-    2. Redistributions in binary form must reproduce the above copyright
-       notice, this list of conditions and the following disclaimer in the
-       documentation and/or other materials provided with the distribution.
-    3. The name of the author may not be used to endorse or promote products
-       derived from this software without specific prior written permission.
+    Permission to use, copy, modify, and distribute this software for any
+    purpose with or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
 
-    THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
-    INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
-    AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
-    THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
-    EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
-    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
-    OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
-    WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
-    OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
-    ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+    THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+    MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
-missing/langinfo.c
+[missing/langinfo.c]
 
   This file is from http://www.cl.cam.ac.uk/~mgk25/ucs/langinfo.c.
   Ruby uses a modified version. The file contains the following
   author/copyright notice:
 
-  Markus.Kuhn@cl.cam.ac.uk -- 2002-03-11
-  Permission to use, copy, modify, and distribute this software
-  for any purpose and without fee is hereby granted. The author
-  disclaims all warranties with regard to this software.
+  >>>
+    Markus.Kuhn@cl.cam.ac.uk -- 2002-03-11::
+    Permission to use, copy, modify, and distribute this software
+    for any purpose and without fee is hereby granted. The author
+    disclaims all warranties with regard to this software.
 
-ext/digest/md5/md5.[ch]:
+[ext/digest/md5/md5.c]
+[ext/digest/md5/md5.h]
 
   These files are under the following license.  Ruby uses modified
   versions of them.
 
-    Copyright (C) 1999, 2000 Aladdin Enterprises.  All rights reserved.
+  >>>
+    Copyright (C) 1999, 2000:: Aladdin Enterprises.  All rights reserved.
 
     This software is provided 'as-is', without any express or implied
     warranty.  In no event will the authors be held liable for any damages
@@ -516,23 +656,27 @@ ext/digest/md5/md5.[ch]:
     L. Peter Deutsch
     ghost@aladdin.com
 
-ext/digest/rmd160/rmd160.[ch]:
+[ext/digest/rmd160/rmd160.c]
+[ext/digest/rmd160/rmd160.h]
 
   These files have the following copyright information, and by the
   author we are allowed to use it under the new-style BSD license.
 
-    AUTHOR:   Antoon Bosselaers, ESAT-COSIC
+  >>>
+    AUTHOR::  Antoon Bosselaers, ESAT-COSIC
               (Arranged for libc by Todd C. Miller)
-    DATE:     1 March 1996
+    DATE::    1 March 1996
 
-    Copyright (c) Katholieke Universiteit Leuven
+    Copyright (c):: Katholieke Universiteit Leuven
     1996, All Rights Reserved
 
-ext/digest/sha2/sha2.[ch]:
+[ext/digest/sha2/sha2.c]
+[ext/digest/sha2/sha2.h]
 
   These files are under the new-style BSD license.
 
-    Copyright 2000 Aaron D. Gifford.  All rights reserved.
+  >>>
+    Copyright 2000:: Aaron D. Gifford.  All rights reserved.
 
     Redistribution and use in source and binary forms, with or without
     modification, are permitted provided that the following conditions
@@ -558,29 +702,123 @@ ext/digest/sha2/sha2.[ch]:
     OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     SUCH DAMAGE.
 
-ext/nkf/nkf-utf8/config.h:
-ext/nkf/nkf-utf8/nkf.c:
-ext/nkf/nkf-utf8/utf8tbl.c:
+[ext/json/generator/generator.c]
+
+  The file contains the following copyright notice.
+
+  >>>
+    Copyright 2001-2004:: Unicode, Inc.
+
+    Disclaimer::
+
+      This source code is provided as is by Unicode, Inc. No claims are
+      made as to fitness for any particular purpose. No warranties of any
+      kind are expressed or implied. The recipient agrees to determine
+      applicability of information provided. If this file has been
+      purchased on magnetic or optical media from Unicode, Inc., the
+      sole remedy for any claim will be exchange of defective media
+      within 90 days of receipt.
+
+    Limitations on Rights to Redistribute This Code::
+
+      Unicode, Inc. hereby grants the right to freely use the information
+      supplied in this file in the creation of products supporting the
+      Unicode Standard, and to make copies of this file in any form
+      for internal or external distribution as long as this notice
+      remains attached.
+
+[ext/nkf/nkf-utf8/config.h]
+[ext/nkf/nkf-utf8/nkf.c]
+[ext/nkf/nkf-utf8/utf8tbl.c]
 
   These files are under the following license.  So to speak, it is
   copyrighted semi-public-domain software.
 
-    Copyright (C) 1987, Fujitsu LTD. (Itaru ICHIKAWA)
-       Everyone is permitted to do anything on this program
-       including copying, modifying, improving,
-       as long as you don't try to pretend that you wrote it.
-       i.e., the above copyright notice has to appear in all copies.
-       Binary distribution requires original version messages.
-       You don't have to ask before copying, redistribution or publishing.
-       THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE.
+  >>>
+    Copyright (C) 1987:: Fujitsu LTD. (Itaru ICHIKAWA)
+
+    Everyone is permitted to do anything on this program
+    including copying, modifying, improving,
+    as long as you don't try to pretend that you wrote it.
+    i.e., the above copyright notice has to appear in all copies.
+    Binary distribution requires original version messages.
+    You don't have to ask before copying, redistribution or publishing.
+    THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE.
+
+[ext/psych]
+[test/psych]
+
+  The files under these directories are under the following license, except for
+  ext/psych/yaml.
+
+  >>>
+    Copyright 2009:: Aaron Patterson, et al.
 
-ext/socket/addrinfo.h:
-ext/socket/getaddrinfo.c:
-ext/socket/getnameinfo.c:
+    Permission is hereby granted, free of charge, to any person obtaining a copy of
+    this software and associated documentation files (the 'Software'), to deal in
+    the Software without restriction, including without limitation the rights to
+    use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+    of the Software, and to permit persons to whom the Software is furnished to do
+    so, subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be included in all
+    copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+    SOFTWARE.
+
+[ext/psych/yaml]
+
+  The files under this directory are under the following license.
+
+  >>>
+    Copyright (c) 2006:: Kirill Simonov
+
+    Permission is hereby granted, free of charge, to any person obtaining a copy of
+    this software and associated documentation files (the "Software"), to deal in
+    the Software without restriction, including without limitation the rights to
+    use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+    of the Software, and to permit persons to whom the Software is furnished to do
+    so, subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be included in all
+    copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+    SOFTWARE.
+
+[ext/pty/pty.c]
+
+  >>>
+    C) Copyright 1998:: by Akinori Ito.
+
+    This software may be redistributed freely for this purpose, in full
+    or in part, provided that this entire copyright notice is included
+    on any copies of this software and applications and derivations thereof.
+
+    This software is provided on an "as is" basis, without warranty of any
+    kind, either expressed or implied, as to any matter including, but not
+    limited to warranty of fitness of purpose, or merchantability, or
+    results obtained from use of this software.
+
+[ext/socket/addrinfo.h]
+[ext/socket/getaddrinfo.c]
+[ext/socket/getnameinfo.c]
 
   These files are under the new-style BSD license.
 
-    Copyright (C) 1995, 1996, 1997, 1998, and 1999 WIDE Project.
+  >>>
+    Copyright (C) 1995, 1996, 1997, 1998, and 1999:: WIDE Project.
     All rights reserved.
 
     Redistribution and use in source and binary forms, with or without
@@ -607,17 +845,275 @@ ext/socket/getnameinfo.c:
     OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     SUCH DAMAGE.
 
-ext/win32ole/win32ole.c:
+[ext/win32ole/win32ole.c]
 
   You can apply the Artistic License to this file. (or GPL,
   alternatively)
 
-    (c) 1995 Microsoft Corporation. All rights reserved.
+  >>>
+    (c) 1995:: Microsoft Corporation. All rights reserved.
     Developed by ActiveWare Internet Corp., http://www.ActiveWare.com
 
-    Other modifications Copyright (c) 1997, 1998 by Gurusamy Sarathy
+    Other modifications Copyright (c) 1997, 1998:: by Gurusamy Sarathy
     <gsar@umich.edu> and Jan Dubois <jan.dubois@ibm.net>
 
     You may distribute under the terms of either the GNU General Public
     License or the Artistic License, as specified in the README file
     of the Perl distribution.
+
+  The Wayback Machine url: http://web.archive.org/web/19970607104352/http://www.activeware.com:80/
+
+[lib/rdoc/generator/template/darkfish/css/fonts.css]
+
+  This file is licensed under the {SIL Open Font License}[http://scripts.sil.org/OFL].
+
+[spec/mspec]
+[spec/ruby]
+
+  The files under these directories are under the following license.
+
+  >>>
+    Copyright (c) 2008:: Engine Yard, Inc. All rights reserved.
+
+    Permission is hereby granted, free of charge, to any person
+    obtaining a copy of this software and associated documentation
+    files (the "Software"), to deal in the Software without
+    restriction, including without limitation the rights to use,
+    copy, modify, merge, publish, distribute, sublicense, and/or sell
+    copies of the Software, and to permit persons to whom the
+    Software is furnished to do so, subject to the following
+    conditions:
+
+    The above copyright notice and this permission notice shall be
+    included in all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+    OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+    NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+    HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+    WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+    OTHER DEALINGS IN THE SOFTWARE.
+
+[lib/rubygems.rb]
+[lib/rubygems]
+[test/rubygems]
+
+  RubyGems is under the following license.
+
+  >>>
+    RubyGems is copyrighted free software by Chad Fowler, Rich Kilmer, Jim
+    Weirich and others.  You can redistribute it and/or modify it under
+    either the terms of the {MIT license}[rdoc-label:label-MIT+License], or the conditions
+    below:
+
+    1. You may make and give away verbatim copies of the source form of the
+       software without restriction, provided that you duplicate all of the
+       original copyright notices and associated disclaimers.
+
+    2. You may modify your copy of the software in any way, provided that
+       you do at least ONE of the following:
+
+       a. place your modifications in the Public Domain or otherwise
+          make them Freely Available, such as by posting said
+          modifications to Usenet or an equivalent medium, or by allowing
+          the author to include your modifications in the software.
+
+       b. use the modified software only within your corporation or
+          organization.
+
+       c. give non-standard executables non-standard names, with
+          instructions on where to get the original software distribution.
+
+       d. make other distribution arrangements with the author.
+
+    3. You may distribute the software in object code or executable
+       form, provided that you do at least ONE of the following:
+
+       a. distribute the executables and library files of the software,
+          together with instructions (in the manual page or equivalent)
+          on where to get the original distribution.
+
+       b. accompany the distribution with the machine-readable source of
+          the software.
+
+       c. give non-standard executables non-standard names, with
+          instructions on where to get the original software distribution.
+
+       d. make other distribution arrangements with the author.
+
+    4. You may modify and include the part of the software into any other
+       software (possibly commercial).
+
+    5. The scripts and library files supplied as input to or produced as
+       output from the software do not automatically fall under the
+       copyright of the software, but belong to whomever generated them,
+       and may be sold commercially, and may be aggregated with this
+       software.
+
+    6. THIS SOFTWARE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR
+       IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+       WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+       PURPOSE.
+
+[lib/bundler]
+[lib/bundler.rb]
+[spec/bundler]
+
+  Bundler is under the following license.
+
+  >>>
+    Portions copyright (c) 2010:: Andre Arko
+    Portions copyright (c) 2009:: Engine Yard
+
+    {MIT License}[rdoc-label:label-MIT+License]
+
+[lib/bundler/vendor/thor]
+
+  Thor is under the following license.
+
+  >>>
+    Copyright (c) 2008 Yehuda Katz, Eric Hodel, et al.
+
+    {MIT License}[rdoc-label:label-MIT+License]
+
+[lib/rubygems/resolver/molinillo]
+
+  molinillo is under the following license.
+
+  >>>
+    Copyright (c) 2014 Samuel E. Giddins segiddins@segiddins.me
+
+    {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.
+
+  >>>
+    Copyright (c) 2011 Mike Perham
+
+    {MIT License}[rdoc-label:label-MIT+License]
+
+[lib/bundler/vendor/net-http-persistent]
+
+  net-http-persistent is under the following license.
+
+  >>>
+    Copyright (c) Eric Hodel, Aaron Patterson
+
+    {MIT License}[rdoc-label:label-MIT+License]
+
+[lib/did_you_mean]
+[lib/did_you_mean.rb]
+[test/did_you_mean]
+
+  did_you_mean is under the following license.
+
+  >>>
+    Copyright (c) 2014-2016 Yuki Nishijima
+
+    {MIT License}[rdoc-label:label-MIT+License]
+
+[lib/error_highlight]
+[lib/error_highlight.rb]
+[test/error_highlight]
+
+  error_highlight is under the following license.
+
+  >>>
+    Copyright (c) 2021 Yusuke Endoh
+
+    {MIT License}[rdoc-label:label-MIT+License]
+
+[benchmark/so_ackermann.rb]
+[benchmark/so_array.rb]
+[benchmark/so_binary_trees.rb]
+[benchmark/so_concatenate.rb]
+[benchmark/so_count_words.yml]
+[benchmark/so_exception.rb]
+[benchmark/so_fannkuch.rb]
+[benchmark/so_fasta.rb]
+[benchmark/so_k_nucleotide.yml]
+[benchmark/so_lists.rb]
+[benchmark/so_mandelbrot.rb]
+[benchmark/so_matrix.rb]
+[benchmark/so_meteor_contest.rb]
+[benchmark/so_nbody.rb]
+[benchmark/so_nested_loop.rb]
+[benchmark/so_nsieve.rb]
+[benchmark/so_nsieve_bits.rb]
+[benchmark/so_object.rb]
+[benchmark/so_partial_sums.rb]
+[benchmark/so_pidigits.rb]
+[benchmark/so_random.rb]
+[benchmark/so_reverse_complement.yml]
+[benchmark/so_sieve.rb]
+[benchmark/so_spectralnorm.rb]
+
+  These files are very old copy of then-called "The Great Computer Language
+  Shootout".  LEGAL SITUATION OF THESE FILES ARE UNCLEAR because the original
+  site has been lost.  Upstream diverged to delete several benchmarks listed
+  above.
+
+== MIT License
+>>>
+      Permission is hereby granted, free of charge, to any person obtaining
+      a copy of this software and associated documentation files (the
+      "Software"), to deal in the Software without restriction, including
+      without limitation the rights to use, copy, modify, merge, publish,
+      distribute, sublicense, and/or sell copies of the Software, and to
+      permit persons to whom the Software is furnished to do so, subject to
+      the following conditions:
+
+      The above copyright notice and this permission notice shall be
+      included in all copies or substantial portions of the Software.
+
+      THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+      EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+      MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+      NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+      LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+      OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+      WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+== Old-style BSD license
+>>>
+      Redistribution and use in source and binary forms, with or without
+      modification, are permitted provided that the following conditions
+      are met:
+      1. Redistributions of source code must retain the above copyright
+         notice, this list of conditions and the following disclaimer.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, this list of conditions and the following disclaimer in the
+         documentation and/or other materials provided with the distribution.
+      3. Neither the name of the University nor the names of its contributors
+         may be used to endorse or promote products derived from this software
+         without specific prior written permission.
+
+      THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+      ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+      IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+      ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+      FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+      DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+      OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+      HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+      LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+      OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+      SUCH DAMAGE.
+
+      IMPORTANT NOTE::
+
+      From ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change
+      paragraph 3 above is now null and void.
diff --git a/Makefile.in b/Makefile.in
deleted file mode 100644
index 09b7ca3322..0000000000
--- a/Makefile.in
+++ /dev/null
@@ -1,550 +0,0 @@
-SHELL = /bin/sh
-NULLCMD = @NULLCMD@
-n=$(NULLCMD)
-ECHO1 = $(V:1=$n)
-RUNCMD = $(SHELL)
-CDPATH = .
-CHDIR = @CHDIR@
-exec = exec
-NULL = /dev/null
-PATH_SEPARATOR = @PATH_SEPARATOR@
-
-#### Start of system configuration section. ####
-
-srcdir = @srcdir@
-top_srcdir = $(srcdir)
-hdrdir = $(srcdir)/include
-PLATFORM_DIR = @PLATFORM_DIR@
-
-CC = @CC@
-CPP = @CPP@
-LD = @LD@
-YACC = bison
-PURIFY =
-AUTOCONF = autoconf
-ACLOCAL = aclocal
-CONFIGURE = @CONFIGURE@
-@SET_MAKE@
-MKFILES = @MAKEFILES@
-BASERUBY = @BASERUBY@
-HAVE_BASERUBY = @HAVE_BASERUBY@
-TEST_RUNNABLE = @TEST_RUNNABLE@
-CROSS_COMPILING = @CROSS_COMPILING@
-DOXYGEN = @DOXYGEN@
-
-prefix = @prefix@
-exec_prefix = @exec_prefix@
-bindir = @bindir@
-sbindir = @sbindir@
-libdir = @libdir@
-libexecdir = @libexecdir@
-datarootdir = @datarootdir@
-datadir = @datadir@
-arch = @arch@
-sitearch = @sitearch@
-sitedir = @sitedir@
-archlibdir = @archlibdir@
-ruby_version = @ruby_version@
-
-TESTUI = console
-TESTS =
-INSTALLDOC = @INSTALLDOC@
-DOCTARGETS = @RDOCTARGET@ @CAPITARGET@
-
-EXTOUT = @EXTOUT@
-arch_hdrdir = $(EXTOUT)/include/$(arch)
-VPATH = $(arch_hdrdir)/ruby:$(hdrdir)/ruby:$(srcdir):$(srcdir)/missing
-
-empty =
-CC_VERSION = @CC_VERSION@
-OUTFLAG = @OUTFLAG@$(empty)
-COUTFLAG = @COUTFLAG@$(empty)
-ARCH_FLAG = @ARCH_FLAG@
-CFLAGS_NO_ARCH = @CFLAGS@
-CFLAGS = $(CFLAGS_NO_ARCH) $(ARCH_FLAG)
-cflags = @cflags@
-optflags = @optflags@
-debugflags = @debugflags@
-warnflags = @warnflags@ @strict_warnflags@
-cppflags = @cppflags@
-INCFLAGS = -I. -I$(arch_hdrdir) -I$(hdrdir) -I$(srcdir)
-XCFLAGS = @XCFLAGS@
-CPPFLAGS = @CPPFLAGS@ $(INCFLAGS)
-LDFLAGS = @STATIC@ $(CFLAGS) @LDFLAGS@
-EXTLDFLAGS = @EXTLDFLAGS@
-XLDFLAGS = @XLDFLAGS@ $(EXTLDFLAGS)
-EXTLIBS =
-LIBS = @LIBS@ $(EXTLIBS)
-MISSING = @LIBOBJS@ @ALLOCA@
-LDSHARED = @LIBRUBY_LDSHARED@
-DLDFLAGS = @LIBRUBY_DLDFLAGS@ $(XLDFLAGS) $(ARCH_FLAG)
-SOLIBS = @SOLIBS@
-MAINLIBS = @MAINLIBS@
-ARCHMINIOBJS = @MINIOBJS@
-DLNOBJ = @DLNOBJ@
-ENCOBJS = @ENCOBJS@
-EXTOBJS = @EXTOBJS@
-BUILTIN_ENCOBJS = @BUILTIN_ENCOBJS@
-BUILTIN_TRANSSRCS = @BUILTIN_TRANSSRCS@
-BUILTIN_TRANSOBJS = @BUILTIN_TRANSOBJS@
-POSTLINK = @POSTLINK@
-
-RUBY_BASE_NAME=@RUBY_BASE_NAME@
-RUBY_PROGRAM_VERSION=@RUBY_PROGRAM_VERSION@
-RUBY_INSTALL_NAME=@RUBY_INSTALL_NAME@
-RUBY_SO_NAME=@RUBY_SO_NAME@
-EXEEXT = @EXEEXT@
-LIBEXT = @LIBEXT@
-PROGRAM=$(RUBY_INSTALL_NAME)$(EXEEXT)
-RUBY = $(RUBY_INSTALL_NAME)
-MINIRUBY = @MINIRUBY@\
-	$(MINIRUBYOPT)
-# RUNRUBY_COMMAND:: runruby.rb or baseruby. do not append options directly
-RUNRUBY_COMMAND = @RUNRUBY_COMMAND@
-# RUNRUBY:: run ruby with RUN_OPTS which is passed to ruby
-RUNRUBY = @RUNRUBY@ $(RUN_OPTS)
-# RUNRUBY_DEBUGGER:: debugging option for runruby.rb
-RUNRUBY_DEBUGGER = --debugger='gdb -x run.gdb --quiet --args'
-XRUBY = @XRUBY@
-BTESTRUBY = @BTESTRUBY@\
-	$(MINIRUBYOPT)
-INSTALL = @INSTALL@
-INSTALL_DATA = @INSTALL_DATA@
-INSTALL_SCRIPT = @INSTALL_SCRIPT@
-INSTALL_PROGRAM = @INSTALL_PROGRAM@
-XRUBY_LIBDIR = @XRUBY_LIBDIR@
-XRUBY_RUBYLIBDIR = @XRUBY_RUBYLIBDIR@
-XRUBY_RUBYHDRDIR = @XRUBY_RUBYHDRDIR@
-BOOTSTRAPRUBY = @BOOTSTRAPRUBY@
-
-#### End of system configuration section. ####
-
-MAJOR=	@MAJOR@
-MINOR=	@MINOR@
-TEENY=	@TEENY@
-RUBY_PROGRAM_VERSION = @RUBY_PROGRAM_VERSION@
-
-LIBRUBY_A     = @LIBRUBY_A@
-LIBRUBY_SO    = @LIBRUBY_SO@
-LIBRUBY_ALIASES= @LIBRUBY_ALIASES@
-LIBRUBY	      = @LIBRUBY@
-LIBRUBYARG    = @LIBRUBYARG@
-LIBRUBYARG_STATIC = @LIBRUBYARG_STATIC@
-LIBRUBYARG_SHARED = @LIBRUBYARG_SHARED@
-LIBRUBY_RELATIVE = @LIBRUBY_RELATIVE@
-LIBRUBY_A_OBJS = @LIBRUBY_A_OBJS@
-
-DTRACE_REBUILD_OBJS = $(DTRACE_REBUILD:yes=$(DTRACE_DEPENDENT_OBJS))
-
-DTRACE_DEPENDENT_OBJS = array.$(OBJEXT) \
-			eval.$(OBJEXT) \
-			gc.$(OBJEXT) \
-			hash.$(OBJEXT) \
-			load.$(OBJEXT) \
-			object.$(OBJEXT) \
-			parse.$(OBJEXT) \
-			string.$(OBJEXT) \
-			symbol.$(OBJEXT) \
-			vm.$(OBJEXT)
-
-THREAD_MODEL  = @THREAD_MODEL@
-
-PREP          = @PREP@
-ARCHFILE      = @ARCHFILE@
-SETUP         =
-EXTSTATIC     = @EXTSTATIC@
-ENCSTATIC     = @ENCSTATIC@
-SET_LC_MESSAGES = env LC_MESSAGES=C
-
-MAKEDIRS      = @MKDIR_P@
-CP            = cp
-MV            = mv
-RM            = rm -f
-RMDIR         = @RMDIR@
-RMDIRS        = @RMDIRS@
-RMALL         = @RMALL@
-NM            = @NM@
-AR            = @AR@
-ARFLAGS       = @ARFLAGS@
-RANLIB        = @RANLIB@
-AS            = @AS@
-ASFLAGS       = @ASFLAGS@ $(INCFLAGS)
-IFCHANGE      = $(srcdir)/tool/ifchange
-SET_LC_MESSAGES = env LC_MESSAGES=C
-OBJDUMP       = @OBJDUMP@
-OBJCOPY       = @OBJCOPY@
-VCS           = @VCS@
-VCSUP         = @VCSUP@
-DTRACE        = @DTRACE@
-DTRACE_EXT    = @DTRACE_EXT@
-DTRACE_OBJ    = @DTRACE_OBJ@
-DTRACE_REBUILD= @DTRACE_REBUILD@
-DTRACE_GLOMMED_OBJ = $(DTRACE_REBUILD:yes=ruby-glommed.$(OBJEXT))
-
-OBJEXT        = @OBJEXT@
-ASMEXT        = S
-DLEXT         = @DLEXT@
-MANTYPE	      = @MANTYPE@
-SYMBOL_PREFIX = @SYMBOL_PREFIX@
-
-INSTALLED_LIST= .installed.list
-
-NEWLINE_C     = enc/trans/newline.c
-MINIPRELUDE_C = miniprelude.c
-PRELUDE_C     = prelude.c
-RBCONFIG      = .rbconfig.time
-
-SRC_FILE      = $<
-OS_SRC_FILE   = $<
-DEST_FILE     = $@
-OS_DEST_FILE  = $@
-
-MESSAGE_BEGIN = @for line in
-MESSAGE_END = ; do echo "$$line"; done
-ECHO_BEGIN = @sep=''; for word in
-ECHO_END = ; do echo @ECHO_N@ "$$sep'$$word'@ECHO_C@"; sep=' '; done; echo
-
-DESTDIR       = @DESTDIR@
-
-configure_args = @configure_args@
-#### End of variables
-
-.SUFFIXES: .inc .h .c .y .i .$(DTRACE_EXT)
-
-all:
-
-# Prevent GNU make v3 from overflowing arg limit on SysV.
-.NOEXPORT:
-
-miniruby$(EXEEXT):
-		@-if test -f $@; then $(MV) -f $@ $@.old; $(RM) $@.old; fi
-		$(ECHO) linking $@
-		$(Q) $(PURIFY) $(CC) $(LDFLAGS) $(XLDFLAGS) $(NORMALMAINOBJ) $(MINIOBJS) $(COMMONOBJS) $(MAINLIBS) $(LIBS) $(OUTFLAG)$@
-
-$(PROGRAM):
-		@$(RM) $@
-		$(ECHO) linking $@
-		$(Q) $(PURIFY) $(CC) $(LDFLAGS) $(XLDFLAGS) $(MAINOBJ) $(EXTOBJS) $(LIBRUBYARG) $(MAINLIBS) $(LIBS) $(EXTLIBS) $(OUTFLAG)$@
-		$(Q) $(POSTLINK)
-
-# We must `rm' the library each time this rule is invoked because "updating" a
-# MAB library on Apple/NeXT (see --enable-fat-binary in configure) is not
-# supported.
-$(LIBRUBY_A):
-		@$(RM) $@
-		$(ECHO) linking static-library $@
-		$(Q) $(AR) $(ARFLAGS) $@ $(LIBRUBY_A_OBJS) $(INITOBJS)
-		@-$(RANLIB) $@ 2> /dev/null || true
-		$(ECHO) verifying static-library $@
-		@$(PURIFY) $(CC) $(LDFLAGS) $(XLDFLAGS) $(MAINOBJ) $(LIBRUBY_A) $(MAINLIBS) $(EXTLIBS) $(LIBS) $(OUTFLAG)conftest$(EXEEXT)
-		@$(RM) conftest$(EXEEXT) conftest.c
-
-$(LIBRUBY_SO):
-		@-$(PRE_LIBRUBY_UPDATE)
-		$(ECHO) linking shared-library $@
-		$(Q) $(LDSHARED) $(DLDFLAGS) $(OBJS) $(DLDOBJS) $(SOLIBS) $(EXTSOLIBS) $(OUTFLAG)$@
-		-$(Q) $(OBJCOPY) -w -L '$(SYMBOL_PREFIX)Init_*' -L '$(SYMBOL_PREFIX)ruby_static_id_*' \
-			-L '$(SYMBOL_PREFIX)*_threadptr_*' $@
-		$(Q) $(POSTLINK)
-		@-$(MINIRUBY) -e 'ARGV.each{|link| File.delete link rescue nil; \
-						  File.symlink "$(LIBRUBY_SO)", link}' \
-				$(LIBRUBY_ALIASES) || true
-
-ruby_pc = @ruby_pc@
-$(ruby_pc):
-		@./config.status --file=$@:$(srcdir)/template/ruby.pc.in
-
-ruby-runner.h: template/ruby-runner.h.in
-		@./config.status --file=$@:$(srcdir)/template/$(@F).in
-
-ruby-runner$(EXEEXT): ruby-runner.c ruby-runner.h
-	$(Q) $(PURIFY) $(CC) $(CFLAGS) $(CPPFLAGS) -DRUBY_INSTALL_NAME=$(RUBY_INSTALL_NAME) $(LDFLAGS) $(LIBS) $(OUTFLAG)$@ $<
-
-$(RBCONFIG): $(PREP)
-
-rbconfig.rb: $(RBCONFIG)
-
-install-cross: $(arch)-fake.rb $(RBCONFIG) rbconfig.rb $(arch_hdrdir)/ruby/config.h \
-	$(LIBRUBY_A) $(LIBRUBY_SO) $(ARCHFILE)
-	$(ECHO) installing cross-compiling stuff
-	$(Q) $(MAKEDIRS) $(XRUBY_RUBYLIBDIR)/$(arch) $(XRUBY_RUBYHDRDIR)/$(arch)/ruby
-	$(Q) sed '/^\$$:\.unshift/q' $(arch)-fake.rb > fake.rb
-	$(Q) $(BASERUBY) -p \
-	-e '~/^\s*CONFIG\["LDFLAGS"\]/ and' \
-	-e '$$_[/(?=\s*"$$)/] = %q[ #{(CONFIG["LIBPATHFLAG"]%File.dirname(__FILE__)).strip}]' \
-	rbconfig.rb > fake-rbconfig.rb
-	$(INSTALL_SCRIPT) fake.rb $(XRUBY_RUBYLIBDIR)/$(arch)/fake.rb
-	$(INSTALL_SCRIPT) fake-rbconfig.rb $(XRUBY_RUBYLIBDIR)/$(arch)/rbconfig.rb
-	@$(RM) fake.rb fake-rbconfig.rb
-	$(INSTALL_DATA) $(arch_hdrdir)/ruby/config.h $(XRUBY_RUBYHDRDIR)/$(arch)/ruby
-	$(INSTALL_DATA) $(top_srcdir)/include/ruby/win32.h $(XRUBY_RUBYHDRDIR)/ruby
-	$(INSTALL_DATA) $(LIBRUBY) $(LIBRUBY_A) $(XRUBY_RUBYLIBDIR)/$(arch)
-	$(INSTALL_PROGRAM) $(LIBRUBY_SO) $(XRUBY_RUBYLIBDIR)/$(arch)
-
-Makefile:	$(srcdir)/Makefile.in $(srcdir)/enc/Makefile.in
-
-$(MKFILES): config.status $(srcdir)/version.h
-		@[ -f $@ ] && mv $@ $@.old
-		MAKE=$(MAKE) $(SHELL) ./config.status $@
-		@cmp $@ $@.old > /dev/null 2>&1 && echo $@ unchanged && exit 0; \
-		{ \
-		    echo "all:; -@rm -f conftest.mk"; \
-		    echo "conftest.mk: .force; @echo AUTO_REMAKE"; \
-		    echo ".force:"; \
-		} > conftest.mk || exit 1; \
-		$(MAKE) -f conftest.mk | grep '^AUTO_REMAKE$$' >/dev/null 2>&1 || \
-		{ echo "$@ updated, restart."; exit 1; }
-
-uncommon.mk: $(srcdir)/common.mk
-		sed 's/{\$$([^(){}]*)[^{}]*}//g' $< > $@
-
-.PHONY: reconfig
-reconfig-args = $(srcdir)/$(CONFIGURE) $(configure_args)
-config.status-args = ./config.status --recheck
-reconfig-exec-0 = test -t 1 && { CONFIGURE_TTY=yes; export CONFIGURE_TTY; }; exec 3>&1; exit `exec 4>&1; { "$$@" 3>&- 4>&-; echo $$? 1>&4; } | fgrep -v '(cached)' 1>&3 3>&- 4>&-`
-reconfig-exec-1 = set -x; "$$@"
-
-reconfig config.status:	$(srcdir)/$(CONFIGURE) $(srcdir)/enc/Makefile.in \
-			$(srcdir)/include/ruby/version.h
-	@PWD= MINIRUBY="$(MINIRUBY)"; export MINIRUBY; \
-	set $(SHELL) $($@-args); $(reconfig-exec-$(V))
-
-$(srcdir)/$(CONFIGURE): $(srcdir)/configure.in $(srcdir)/aclocal.m4
-	$(CHDIR) $(srcdir) && exec $(AUTOCONF) -o $(@F)
-
-$(srcdir)/aclocal.m4:
-	$(CHDIR) $(srcdir) && \
-	type $(ACLOCAL) >/dev/null 2>&1 && exec $(ACLOCAL); \
-	touch $(@F)
-
-incs: id.h
-all-incs: probes.h
-
-# Things which should be considered:
-# * with gperf v.s. without gperf
-# * committers may have various versions of gperf
-# * ./configure v.s. ../ruby/configure
-# * GNU make v.s. HP-UX make	# HP-UX make invokes the action if lex.c and keywords has same mtime.
-# * svn checkout generate a file with mtime as current time
-# * ext4 and XFS has a mtime with fractional part
-lex.c: defs/keywords
-	@\
-	if cmp -s $(srcdir)/defs/lex.c.src $?; then \
-	  [ $(Q) ] && echo copying $@ || set -x; \
-	  $(CP) $(srcdir)/lex.c.blt $@; \
-	else \
-	  [ $(Q) ] && echo generating $@ || set -x; \
-	  gperf -C -P -p -j1 -i 1 -g -o -t -N rb_reserved_word -k1,3,$$ $? \
-	  | sed 's/(long)&((\(struct stringpool_t\) *\*)0)->\(stringpool_[a-z0-9]*\)/offsetof(\1, \2)/g' \
-	  > $@.tmp && \
-	  $(MV) $@.tmp $@ && \
-	  $(CP) $? $(srcdir)/defs/lex.c.src && \
-	  $(CP) $@ $(srcdir)/lex.c.blt; \
-	fi
-
-JIS_PROPS_OPTIONS = -k1,3 -7 -c -j1 -i1 -t -C -P -t --ignore-case -H onig_jis_property_hash -Q onig_jis_property_pool -N onig_jis_property
-
-enc/jis/props.h: enc/jis/props.kwd
-	$(MAKEDIRS) $(@D)
-	@set +e; \
-	if cmp -s $(?:.kwd=.src) $?; then \
-	  set -x; \
-	  $(CP) $(?:.kwd=.h.blt) $@; \
-	else \
-	  set -x; \
-	  gperf $(JIS_PROPS_OPTIONS) $? | \
-	  sed 's/(int)(long)&((\([a-zA-Z_0-9 ]*[a-zA-Z_0-9]\) *\*)0)->\([a-zA-Z0-9_]*\),/(char)offsetof(\1, \2),/g' > $@ && \
-	  $(CP) $? $(?:.kwd=.src) && \
-	  $(CP) $@ $(?:.kwd=.h.blt); \
-	fi
-
-.c.@OBJEXT@:
-	@$(ECHO) compiling $<
-	$(Q) $(CC) $(CFLAGS) $(XCFLAGS) $(CPPFLAGS) $(COUTFLAG)$@ -c $<
-
-.s.@OBJEXT@:
-	@$(ECHO) assembling $<
-	$(Q) $(AS) $(ASFLAGS) -o $@ $<
-
-.c.S:
-	@$(ECHO) translating $<
-	$(Q) $(CC) $(CFLAGS) $(XCFLAGS) $(CPPFLAGS) $(COUTFLAG)$@ -S $<
-
-.c.i:
-	@$(ECHO) preprocessing $<
-	$(Q) $(CPP) $(warnflags) $(XCFLAGS) $(CPPFLAGS) $(COUTFLAG)$@ -E $< > $@
-
-.d.h:
-	@$(ECHO) translating probes $<
-	$(Q) $(DTRACE) -o $@.tmp -h -C $(INCFLAGS) -s $<
-	$(Q) sed -e 's/RUBY_/RUBY_DTRACE_/g' -e 's/PROBES_H_TMP/RUBY_PROBES_H/' -e 's/(char \*/(const char */g' -e 's/, char \*/, const char */g' $@.tmp > $@
-	$(Q) $(RM) $@.tmp
-
-.dmyh.h:
-	@$(ECHO) making dummy $(DEST_FILE)
-	$(Q)echo '#include "$(*F).dmyh"' > $@
-
-probes.stamp: $(DTRACE_REBUILD_OBJS)
-	$(Q) if test -f $@ -o -f probes.$(OBJEXT); then \
-	  $(RM) $(DTRACE_REBUILD_OBJS) $@; \
-	  $(ECHO0) "rebuilding objects which were modified by \"dtrace -G\""; \
-	  $(MAKE) $(DTRACE_REBUILD_OBJS); \
-	fi
-	$(Q) touch $@
-
-probes.@OBJEXT@: $(srcdir)/probes.d $(DTRACE_REBUILD:yes=probes.stamp)
-	@$(ECHO) processing probes in object files
-	$(Q) $(RM) $@
-	$(Q) $(DTRACE) -G -C $(INCFLAGS) -s $(srcdir)/probes.d -o $@ $(DTRACE_REBUILD_OBJS)
-
-# DTrace static library hacks described here:
-# http://mail.opensolaris.org/pipermail/dtrace-discuss/2005-August/000207.html
-ruby-glommed.$(OBJEXT):
-	@$(ECHO) generating a glommed object with DTrace probes for static library
-	$(Q) $(LD) -r -o $@ $(OBJS)
-
-clean-local::
-	$(Q)$(RM) ext/extinit.c ext/extinit.$(OBJEXT) ext/ripper/y.output \
-		enc/encinit.c enc/encinit.$(OBJEXT)
-	-$(Q)$(RM) $(pkgconfig_DATA)
-
-distclean-local::
-	$(Q)$(RM) ext/config.cache $(RBCONFIG) Doxyfile
-	-$(Q)$(RM) run.gdb
-	-$(Q)$(RM) $(INSTALLED_LIST) $(arch_hdrdir)/ruby/config.h verconf.h
-	-$(Q)$(RMDIRS) $(arch_hdrdir)/ruby 2> /dev/null || true
-
-clean-ext distclean-ext realclean-ext::
-	@cd ext 2>/dev/null || exit 0; set dummy `echo "${EXTS}" | tr , ' '`; shift; \
-	test "$$#" = 0 && set .; \
-	set dummy `\
-	    find "$$@" -name Makefile -print | sed 's:^\./::;s:/Makefile$$::' | sort; \
-	`; shift; \
-	cd ..; \
-	for dir do \
-	    echo $(@:-ext=)ing "$$dir"; \
-	    (cd "ext/$$dir" && exec $(MAKE) $(MFLAGS) $(@:-ext=)) && \
-	    case "$@" in \
-	    *distclean-ext*|*realclean-ext*) \
-		$(RMDIRS) "ext/$$dir" 2> /dev/null || true;; \
-	    esac; \
-	done
-	-$(Q)$(RM) ext/extinit.$(OBJEXT)
-
-distclean-ext realclean-ext::
-	-$(Q)$(RM) ext/extinit.c
-	-$(Q)$(RMDIR) ext 2> /dev/null || true
-
-clean-extout:
-
-clean-enc distclean-enc realclean-enc:
-	@test -f "$(ENC_MK)" || exit 0; \
-	echo $(@:-enc=ing) encodings; \
-	exec $(MAKE) -f $(ENC_MK) $(MFLAGS) $(@:-enc=)
-
-ext/extinit.$(OBJEXT): ext/extinit.c $(SETUP)
-	$(ECHO) compiling $@
-	$(Q) $(CC) $(CFLAGS) $(XCFLAGS) $(CPPFLAGS) $(COUTFLAG)$@ -c ext/extinit.c
-
-enc/encinit.$(OBJEXT): enc/encinit.c $(SETUP)
-
-update-src::
-	@$(CHDIR) "$(srcdir)" && LC_TIME=C exec $(VCSUP)
-
-update-download:: update-config_files
-
-after-update:: common-srcs
-
-update-mspec:
-	@$(CHDIR) $(srcdir); \
-	if [ -d spec/mspec ]; then \
-	  echo updating mspec ...; \
-	  $(Q1:0=:) set -x; \
-	  cd spec/mspec && \
-	  exec git pull; \
-	else \
-	  echo retrieving mspec ...; \
-	  $(Q1:0=:) set -x; \
-	  exec git clone $(MSPEC_GIT_URL) spec/mspec; \
-	fi
-	$(Q)cd $(srcdir)/spec/mspec && exec git --no-pager log -1 --oneline
-
-update-rubyspec: update-mspec
-	@$(CHDIR) $(srcdir); \
-	if [ -d spec/rubyspec ]; then \
-	  echo updating rubyspec ...; \
-	  $(Q1:0=:) set -x; \
-	  cd spec/rubyspec && \
-	  exec git pull; \
-	else \
-	  echo retrieving rubyspec ...; \
-	  $(Q1:0=:) set -x; \
-	  exec git clone $(RUBYSPEC_GIT_URL) spec/rubyspec; \
-	fi
-	$(Q)cd $(srcdir)/spec/rubyspec && exec git --no-pager log -1 --oneline
-
-test-rubyspec-precheck:
-	@if [ ! -d $(srcdir)/spec/rubyspec ]; then echo No rubyspec here.  make update-rubyspec first.; exit 1; fi
-
-update-doclie:
-	@$(CHDIR) $(srcdir); \
-	if [ -d coverage/doclie ]; then \
-	  echo updating doclie ...; \
-	  $(Q1:0=:) set -x; \
-	  cd coverage/doclie && \
-	  git fetch && \
-	  exec git checkout $(DOCLIE_GIT_REF); \
-	else \
-	  echo retrieving doclie ...; \
-	  $(Q1:0=:) set -x; \
-	  exec git clone --branch $(DOCLIE_GIT_REF) $(DOCLIE_GIT_URL) coverage/doclie; \
-	fi
-
-update-simplecov-html:
-	@$(CHDIR) $(srcdir); \
-	if [ -d coverage/simplecov-html ]; then \
-	  echo updating simplecov-html ...; \
-	  $(Q1:0=:) set -x; \
-	  cd coverage/simplecov-html && \
-	  git fetch && \
-	  exec git checkout $(SIMPLECOV_HTML_GIT_REF); \
-	else \
-	  echo retrieving simplecov-html ...; \
-	  exec git clone --branch $(SIMPLECOV_HTML_GIT_REF) $(SIMPLECOV_HTML_GIT_URL) coverage/simplecov-html; \
-	fi
-
-update-simplecov:
-	@$(CHDIR) $(srcdir); \
-	if [ -d coverage/simplecov ]; then \
-	  echo updating simplecov ...; \
-	  $(Q1:0=:) set -x; \
-	  cd coverage/simplecov && \
-	  git fetch && \
-	  exec git checkout $(SIMPLECOV_GIT_REF); \
-	else \
-	  echo retrieving simplecov ...; \
-	  $(Q1:0=:) set -x; \
-	  exec git clone --branch $(SIMPLECOV_GIT_REF) $(SIMPLECOV_GIT_URL) coverage/simplecov; \
-	fi
-
-update-coverage: update-simplecov update-simplecov-html update-doclie
-
-INSNS	= opt_sc.inc optinsn.inc optunifs.inc insns.inc insns_info.inc \
-	  vmtc.inc vm.inc
-
-$(INSNS): $(srcdir)/insns.def vm_opts.h \
-	  $(srcdir)/defs/opt_operand.def $(srcdir)/defs/opt_insn_unif.def \
-	  $(srcdir)/tool/instruction.rb $(srcdir)/tool/insns2vm.rb
-	$(ECHO) generating $@
-	$(Q) $(BASERUBY) -Ku $(srcdir)/tool/insns2vm.rb $(INSNS2VMOPT) $@
-
-verconf.h: $(RBCONFIG)
-
-loadpath: verconf.h
-	@$(CPP) $(XCFLAGS) $(CPPFLAGS) $(srcdir)/loadpath.c | \
-	sed -e '1,/^const char ruby_initial_load_paths/d;/;/,$$d' \
-	    -e '/^ /!d;s/ *"\\0"$$//;s/" *"//g'
-
-un-runnable:
-	$(ECHO) cannot make runnable, configure with --enable-load-relative.
-	$(Q) exit 1
diff --git a/NEWS b/NEWS
deleted file mode 100644
index 947d0074f9..0000000000
--- a/NEWS
+++ /dev/null
@@ -1,176 +0,0 @@
-# -*- rdoc -*-
-
-= NEWS for Ruby 2.4.0
-
-This document is a list of user visible feature changes made between
-releases except for bug fixes.
-
-Note that each entry is kept so brief that no reason behind or
-reference information is supplied with.  For a full list of changes
-with all sufficient information, see the ChangeLog file or Redmine
-(e.g. <tt>https://bugs.ruby-lang.org/issues/$FEATURE_OR_BUG_NUMBER</tt>)
-
-== Changes since the 2.3.0 release
-
-=== Language changes
-
-* Multiple assignment in conditional expression is now allowed.
-  [Feature #10617]
-
-=== Core classes updates (outstanding ones only)
-
-* Array
-
-  * Array#max and Array#min.  [Feature #12172]
-    This may cause a tiny incompatibility: if you redefine
-    Enumerable#max and call max to an Array, your redefinition will be
-    now ignored.  You should also redefine Array#max.
-
-  * Array#sum  [Feature #12217]
-    This is different from Enumerable#sum in that Array#sum doesn't depend on
-    the definition of each method.
-
-* Dir
-
-  * Dir.empty?.  [Feature #10121]
-
-* Enumerable
-
-  * Enumerable#sum  [Feature #12217]
-
-* File
-
-  * File.empty?.  [Feature #9969]
-
-* Float
-
-  * Float#ceil, Float#floor, and Float#truncate now take an optional
-    digits, as well as Float#round.  [Feature #12245]
-
-* Integer
-
-  * Integer#ceil, Integer#floor, and Integer#truncate now take an optional
-    digits, as well as Integer#round.  [Feature #12245]
-
-  * Fixnum and Bignum are unified into Integer  [Feature #12005]
-
-  * Integer#digits for extracting columns of place-value notation [Feature #12447]
-
-* Regexp
-
-  * Regexp#match? [Feature #8110]
-    This returns bool and doesn't save backref.
-
-* String
-
-  * String#upcase, String#downcase, String#capitalize, String#swapcase and
-    their bang variants work for all of Unicode, and are no longer limited
-    to ASCII. Variations are available with options. See the documentation
-    of String#downcase for details. [Feature #10085]
-
-  * String.new(capacity: size) [Feature #12024]
-
-* Symbol
-
-  * Symbol#match now returns MatchData.  [Bug #11991]
-
-  * Symbol#upcase, Symbol#downcase, Symbol#capitalize, and Symbol#swapcase now
-    work for all of Unicode. See the documentation of String#downcase
-    for details. [Feature #10085]
-
-* MatchData
-
-  * MatchData#named_captures [Feature #11999]
-  * MatchData#values_at supports named captures [Feature #9179]
-
-* Thread
-
-  * Thread#report_on_exception and Thread.report_on_exception
-    [Feature #6647]
-
-=== Stdlib updates (outstanding ones only)
-
-* CSV
-
-  * Add a liberal_parsing option. [Feature #11839]
-
-* Logger
-
-	* Allow specifying logger parameters in constructor such
-	  as level, progname, datetime_format, formatter. [Feature #12224]
-	* Add shift_period_suffix option. [Feature #10772]
-
-* optparse
-
-  * Add an into option. [Feature #11191]
-
-=== Compatibility issues (excluding feature bug fixes)
-
-* Array#sum and Enumerable#sum are implemented.  [Feature #12217]
-  Ruby itself has no compatibility problem because Ruby didn't have sum method
-  for arrays before Ruby 2.4.
-  However many third party gems, activesupport, facets, simple_stats, etc,
-  defines sum method.  These implementations are mostly compatible but
-  there are subtle differences.
-  Ruby's sum method should be mostly compatible but it is impossible to
-  be perfectly compatible with all of them.
-
-* Fixnum and Bignum are unified into Integer  [Feature #12005]
-  Fixnum class and Bignum class is removed.
-  Integer class is changed from abstract class to concrete class.
-  For example, 0 is an instance of Integer: 0.class returns Integer.
-  The constants Fixnum and Bignum is bound to Integer.
-  So obj.kind_of?(Fixnum) works as obj.kind_of?(Integer).
-  At C-level, Fixnum object and Bignum object should be distinguished by
-  FIXNUM_P(obj) and RB_TYPE_P(obj, T_BIGNUM).
-  RUBY_INTEGER_UNIFICATION can be used to detect this feature.
-  ruby-2.4.0-preview1 (temporally) removes rb_cFixnum and rb_cBignum
-  to check the effect of incompatibility.
-  (rb_cFixnum and rb_cBignum may be defined as rb_cInteger later if
-  compilation failure of extension library is too big problem.)
-
-* String/Symbol#upcase/downcase/swapcase/capitalize(!) now work for all of
-  Unicode, not only for ASCII. [Feature #10085]
-  No change is needed if the data is in ASCII anyway or if the limitation
-  to ASCII was only tolerated while waiting for a more extensive implementation.
-  A change (using the :ascii option) is needed in cases where Unicode data
-  is processed, but the operation has to be limited to ASCII only.
-  A good example of this are internationalized domain names.
-
-=== Stdlib compatibility issues (excluding feature bug fixes)
-
-* Time
-
-  * Time#to_time now preserves timezone.  [Bug #12271]
-
-* DateTime
-
-  * DateTime#to_time now preserves timezone.  [Bug #12189]
-
-* thread
-
-  * the extension library is removed.  Till 2.0 it was a pure ruby script
-    "thread.rb", which has precedence over "thread.so", and has been provided
-    in $LOADED_FEATURES since 2.1.
-
-=== C API updates
-
-* ruby_show_version() will no longer exits the process, if
-  RUBY_SHOW_COPYRIGHT_TO_DIE is set to 0.  This will be the default in
-  the future.
-
-=== Supported platform changes
-
-* FreeBSD < 4 is no longer supported
-
-=== Implementation improvements
-
-* In some condition, `[x, y].max` and `[x, y].min` are optimized
-  so that a temporal array is not created.  The concrete condition is
-  an implementation detail: currently, the array literal must have no
-  splat, must have at least one expression but literal, the length must
-  be <= 0x100, and Array#max and min must not be redefined.  It will work
-  in most casual and real-life use case where it is written with intent
-  to `Math.max(x, y)`.
-
-* Thread deadlock detection now shows their backtrace and dependency. [Feature #8214]
diff --git a/NEWS.md b/NEWS.md
new file mode 100644
index 0000000000..f6c3c6fc97
--- /dev/null
+++ b/NEWS.md
@@ -0,0 +1,820 @@
+# NEWS for Ruby 3.2.0
+
+This document is a list of user-visible feature changes
+since the **3.1.0** release, except for bug fixes.
+
+Note that each entry is kept to a minimum, see links for details.
+
+## Language changes
+
+* Anonymous rest and keyword rest arguments can now be passed as
+  arguments, instead of just used in method parameters.
+  [[Feature #18351]]
+
+    ```ruby
+    def foo(*)
+      bar(*)
+    end
+    def baz(**)
+      quux(**)
+    end
+    ```
+
+* A proc that accepts a single positional argument and keywords will
+  no longer autosplat. [[Bug #18633]]
+
+    ```ruby
+    proc{|a, **k| a}.call([1, 2])
+    # Ruby 3.1 and before
+    # => 1
+    # Ruby 3.2 and after
+    # => [1, 2]
+    ```
+
+* Constant assignment evaluation order for constants set on explicit
+  objects has been made consistent with single attribute assignment
+  evaluation order. With this code:
+
+    ```ruby
+    foo::BAR = baz
+    ```
+
+    `foo` is now called before `baz`. Similarly, for multiple assignments
+    to constants,  left-to-right evaluation order is used. With this
+    code:
+
+    ```ruby
+    foo1::BAR1, foo2::BAR2 = baz1, baz2
+    ```
+
+    The following evaluation order is now used:
+
+    1. `foo1`
+    2. `foo2`
+    3. `baz1`
+    4. `baz2`
+
+    [[Bug #15928]]
+
+* "Find pattern" is no longer experimental.
+  [[Feature #18585]]
+
+* Methods taking a rest parameter (like `*args`) and wishing to delegate keyword
+  arguments through `foo(*args)` must now be marked with `ruby2_keywords`
+  (if not already the case). In other words, all methods wishing to delegate
+  keyword arguments through `*args` must now be marked with `ruby2_keywords`,
+  with no exception. This will make it easier to transition to other ways of
+  delegation once a library can require Ruby 3+. Previously, the `ruby2_keywords`
+  flag was kept if the receiving method took `*args`, but this was a bug and an
+  inconsistency. A good technique to find the potentially-missing `ruby2_keywords`
+  is to run the test suite, for where it fails find the last method which must
+  receive keyword arguments, use `puts nil, caller, nil` there, and check each
+  method/block on the call chain which must delegate keywords is correctly marked
+  as `ruby2_keywords`. [[Bug #18625]] [[Bug #16466]]
+
+    ```ruby
+    def target(**kw)
+    end
+
+    # Accidentally worked without ruby2_keywords in Ruby 2.7-3.1, ruby2_keywords
+    # needed in 3.2+. Just like (*args, **kwargs) or (...) would be needed on
+    # both #foo and #bar when migrating away from ruby2_keywords.
+    ruby2_keywords def bar(*args)
+      target(*args)
+    end
+
+    ruby2_keywords def foo(*args)
+      bar(*args)
+    end
+
+    foo(k: 1)
+    ```
+
+## Core classes updates
+
+Note: We're only listing outstanding class updates.
+
+* Fiber
+
+    * Introduce Fiber.[] and Fiber.[]= for inheritable fiber storage.
+      Introduce Fiber#storage and Fiber#storage= (experimental) for
+      getting and resetting the current storage.  Introduce
+      `Fiber.new(storage:)` for setting the storage when creating a
+      fiber. [[Feature #19078]]
+
+        Existing Thread and Fiber local variables can be tricky to use.
+        Thread-local variables are shared between all fibers, making it
+        hard to isolate, while Fiber-local variables can be hard to
+        share.  It is often desirable to define unit of execution
+        ("execution context") such that some state is shared between all
+        fibers and threads created in that context.  This is what Fiber
+        storage provides.
+
+        ```ruby
+        def log(message)
+          puts "#{Fiber[:request_id]}: #{message}"
+        end
+
+        def handle_requests
+          while request = read_request
+            Fiber.schedule do
+              Fiber[:request_id] = SecureRandom.uuid
+
+              request.messages.each do |message|
+                Fiber.schedule do
+                  log("Handling #{message}") # Log includes inherited request_id.
+                end
+              end
+            end
+          end
+        end
+        ```
+
+        You should generally consider Fiber storage for any state which
+        you want to be shared implicitly between all fibers and threads
+        created in a given context, e.g. a connection pool, a request
+        id, a logger level, environment variables, configuration, etc.
+
+* Fiber::Scheduler
+
+    * Introduce `Fiber::Scheduler#io_select` for non-blocking IO.select.
+      [[Feature #19060]]
+
+* IO
+
+    * Introduce IO#timeout= and IO#timeout which can cause
+      IO::TimeoutError to be raised if a blocking operation exceeds the
+      specified timeout. [[Feature #18630]]
+
+        ```ruby
+        STDIN.timeout = 1
+        STDIN.read # => Blocking operation timed out! (IO::TimeoutError)
+        ```
+
+    * Introduce `IO.new(..., path:)` and promote `File#path` to `IO#path`.
+      [[Feature #19036]]
+
+* Class
+
+    * Class#attached_object, which returns the object for which
+      the receiver is the singleton class. Raises TypeError if the
+      receiver is not a singleton class.
+      [[Feature #12084]]
+
+        ```ruby
+        class Foo; end
+
+        Foo.singleton_class.attached_object        #=> Foo
+        Foo.new.singleton_class.attached_object    #=> #<Foo:0x000000010491a370>
+        Foo.attached_object                        #=> TypeError: `Foo' is not a singleton class
+        nil.singleton_class.attached_object        #=> TypeError: `NilClass' is not a singleton class
+        ```
+
+* Data
+
+    * New core class to represent simple immutable value object. The class is
+      similar to Struct and partially shares an implementation, but has more
+      lean and strict API. [[Feature #16122]]
+
+        ```ruby
+        Measure = Data.define(:amount, :unit)
+        distance = Measure.new(100, 'km')            #=> #<data Measure amount=100, unit="km">
+        weight = Measure.new(amount: 50, unit: 'kg') #=> #<data Measure amount=50, unit="kg">
+        weight.with(amount: 40)                      #=> #<data Measure amount=40, unit="kg">
+        weight.amount                                #=> 50
+        weight.amount = 40                           #=> NoMethodError: undefined method `amount='
+        ```
+
+* Encoding
+
+    * Encoding#replicate has been deprecated and will be removed in 3.3. [[Feature #18949]]
+    * The dummy `Encoding::UTF_16` and `Encoding::UTF_32` encodings no longer
+      try to dynamically guess the endian based on a byte order mark.
+      Use `Encoding::UTF_16BE`/`UTF_16LE` and `Encoding::UTF_32BE`/`UTF_32LE` instead.
+      This change speeds up getting the encoding of a String. [[Feature #18949]]
+    * Limit maximum encoding set size by 256.
+      If exceeding maximum size, `EncodingError` will be raised. [[Feature #18949]]
+
+* Enumerator
+
+    * Enumerator.product has been added.  Enumerator::Product is the implementation. [[Feature #18685]]
+
+* Exception
+
+    * Exception#detailed_message has been added.
+      The default error printer calls this method on the Exception object
+      instead of #message. [[Feature #18564]]
+
+* Hash
+
+    * Hash#shift now always returns nil if the hash is
+      empty, instead of returning the default value or
+      calling the default proc. [[Bug #16908]]
+
+* Integer
+
+    * Integer#ceildiv has been added. [[Feature #18809]]
+
+* Kernel
+
+    * Kernel#binding raises RuntimeError if called from a non-Ruby frame
+      (such as a method defined in C). [[Bug #18487]]
+
+* MatchData
+
+    * MatchData#byteoffset has been added. [[Feature #13110]]
+    * MatchData#deconstruct has been added. [[Feature #18821]]
+    * MatchData#deconstruct_keys has been added. [[Feature #18821]]
+
+* Module
+
+    * Module.used_refinements has been added. [[Feature #14332]]
+    * Module#refinements has been added. [[Feature #12737]]
+    * Module#const_added has been added. [[Feature #17881]]
+    * Module#undefined_instance_methods has been added. [[Feature #12655]]
+
+* Proc
+
+    * Proc#dup returns an instance of subclass. [[Bug #17545]]
+    * Proc#parameters now accepts lambda keyword. [[Feature #15357]]
+
+* Process
+    * Added `RLIMIT_NPTS` constant to FreeBSD platform
+
+* Regexp
+
+    * The cache-based optimization is introduced.
+      Many (but not all) Regexp matching is now in linear time, which
+      will prevent regular expression denial of service (ReDoS)
+      vulnerability. [[Feature #19104]]
+
+    * Regexp.linear_time? is introduced. [[Feature #19194]]
+
+    * Regexp.new now supports passing the regexp flags not only as an Integer,
+      but also as a String.  Unknown flags raise ArgumentError.
+      Otherwise, anything other than `true`, `false`, `nil` or Integer will be warned.
+      [[Feature #18788]]
+
+    * Regexp.timeout= has been added. Also, Regexp.new new supports timeout keyword.
+      See [[Feature #17837]]
+
+* Refinement
+
+    * Refinement#refined_class has been added. [[Feature #12737]]
+
+* RubyVM::AbstractSyntaxTree
+
+    * Add `error_tolerant` option for `parse`, `parse_file` and `of`. [[Feature #19013]]
+      With this option
+
+        1. SyntaxError is suppressed
+        2. AST is returned for invalid input
+        3. `end` is complemented when a parser reaches to the end of input but `end` is insufficient
+        4. `end` is treated as keyword based on indent
+
+        ```ruby
+        # Without error_tolerant option
+        root = RubyVM::AbstractSyntaxTree.parse(<<~RUBY)
+        def m
+          a = 10
+          if
+        end
+        RUBY
+        # => <internal:ast>:33:in `parse': syntax error, unexpected `end' (SyntaxError)
+
+        # With error_tolerant option
+        root = RubyVM::AbstractSyntaxTree.parse(<<~RUBY, error_tolerant: true)
+        def m
+          a = 10
+          if
+        end
+        RUBY
+        p root # => #<RubyVM::AbstractSyntaxTree::Node:SCOPE@1:0-4:3>
+
+        # `end` is treated as keyword based on indent
+        root = RubyVM::AbstractSyntaxTree.parse(<<~RUBY, error_tolerant: true)
+        module Z
+          class Foo
+            foo.
+          end
+
+          def bar
+          end
+        end
+        RUBY
+        p root.children[-1].children[-1].children[-1].children[-2..-1]
+        # => [#<RubyVM::AbstractSyntaxTree::Node:CLASS@2:2-4:5>, #<RubyVM::AbstractSyntaxTree::Node:DEFN@6:2-7:5>]
+        ```
+
+    * Add `keep_tokens` option for `parse`, `parse_file` and `of`. Add `#tokens` and `#all_tokens`
+      for RubyVM::AbstractSyntaxTree::Node [[Feature #19070]]
+
+        ```ruby
+        root = RubyVM::AbstractSyntaxTree.parse("x = 1 + 2", keep_tokens: true)
+        root.tokens # => [[0, :tIDENTIFIER, "x", [1, 0, 1, 1]], [1, :tSP, " ", [1, 1, 1, 2]], ...]
+        root.tokens.map{_1[2]}.join # => "x = 1 + 2"
+        ```
+
+* Set
+
+    * Set is now available as a built-in class without the need for `require "set"`. [[Feature #16989]]
+      It is currently autoloaded via the Set constant or a call to Enumerable#to_set.
+
+* String
+
+    * String#byteindex and String#byterindex have been added. [[Feature #13110]]
+    * Update Unicode to Version 15.0.0 and Emoji Version 15.0. [[Feature #18639]]
+      (also applies to Regexp)
+    * String#bytesplice has been added.  [[Feature #18598]]
+    * String#dedup has been added as an alias to String#-@.  [[Feature #18595]]
+
+* Struct
+
+    * A Struct class can also be initialized with keyword arguments
+      without `keyword_init: true` on Struct.new [[Feature #16806]]
+
+        ```ruby
+        Post = Struct.new(:id, :name)
+        Post.new(1, "hello") #=> #<struct Post id=1, name="hello">
+        # From Ruby 3.2, the following code also works without keyword_init: true.
+        Post.new(id: 1, name: "hello") #=> #<struct Post id=1, name="hello">
+        ```
+
+* Thread
+
+    * Thread.each_caller_location is added. [[Feature #16663]]
+
+* Thread::Queue
+
+    * Thread::Queue#pop(timeout: sec) is added. [[Feature #18774]]
+
+* Thread::SizedQueue
+
+    * Thread::SizedQueue#pop(timeout: sec) is added. [[Feature #18774]]
+    * Thread::SizedQueue#push(timeout: sec) is added. [[Feature #18944]]
+
+* Time
+
+    * Time#deconstruct_keys is added, allowing to use Time instances
+      in pattern-matching expressions [[Feature #19071]]
+
+    * Time.new now can parse a string like generated by Time#inspect
+      and return a Time instance based on the given argument.
+      [[Feature #18033]]
+
+* SyntaxError
+    * SyntaxError#path has been added.  [[Feature #19138]]
+
+* TracePoint
+
+    * TracePoint#binding now returns `nil` for `c_call`/`c_return` TracePoints.
+      [[Bug #18487]]
+    * TracePoint#enable `target_thread` keyword argument now defaults to the
+      current thread if a block is given and `target` and `target_line` keyword
+      arguments are not passed. [[Bug #16889]]
+
+* UnboundMethod
+
+    * `UnboundMethod#==` returns `true` if the actual method is same. For example,
+      `String.instance_method(:object_id) == Array.instance_method(:object_id)`
+      returns `true`. [[Feature #18798]]
+
+    * `UnboundMethod#inspect` does not show the receiver of `instance_method`.
+      For example `String.instance_method(:object_id).inspect` returns
+      `"#<UnboundMethod: Kernel#object_id()>"`
+      (was `"#<UnboundMethod: String(Kernel)#object_id()>"`).
+
+* GC
+
+    * Expose `need_major_gc` via `GC.latest_gc_info`. [GH-6791]
+
+* ObjectSpace
+
+    * `ObjectSpace.dump_all` dump shapes as well. [GH-6868]
+
+## Stdlib updates
+
+* Bundler
+
+    * Bundler now uses [PubGrub] resolver instead of [Molinillo] for performance improvement.
+    * Add --ext=rust support to bundle gem for creating simple gems with Rust extensions.
+      [[GH-rubygems-6149]]
+    * Make cloning git repos faster [[GH-rubygems-4475]]
+
+* RubyGems
+
+    * Add mswin support for cargo builder. [[GH-rubygems-6167]]
+
+* CGI
+
+    * `CGI.escapeURIComponent` and `CGI.unescapeURIComponent` are added.
+      [[Feature #18822]]
+
+* Coverage
+
+    * `Coverage.setup` now accepts `eval: true`. By this, `eval` and related methods are
+      able to generate code coverage. [[Feature #19008]]
+
+    * `Coverage.supported?(mode)` enables detection of what coverage modes are
+      supported. [[Feature #19026]]
+
+* Date
+
+    * Added `Date#deconstruct_keys` and `DateTime#deconstruct_keys` same as [[Feature #19071]]
+
+* ERB
+
+    * `ERB::Util.html_escape` is made faster than `CGI.escapeHTML`.
+        * It no longer allocates a String object when no character needs to be escaped.
+        * It skips calling `#to_s` method when an argument is already a String.
+        * `ERB::Escape.html_escape` is added as an alias to `ERB::Util.html_escape`,
+          which has not been monkey-patched by Rails.
+    * `ERB::Util.url_encode` is made faster using `CGI.escapeURIComponent`.
+    * `-S` option is removed from `erb` command.
+
+* FileUtils
+
+    * Add FileUtils.ln_sr method and `relative:` option to FileUtils.ln_s.
+      [[Feature #18925]]
+
+* IRB
+
+    * debug.gem integration commands have been added: `debug`, `break`, `catch`,
+      `next`, `delete`, `step`, `continue`, `finish`, `backtrace`, `info`
+        * They work even if you don't have `gem "debug"` in your Gemfile.
+        * See also: [What's new in Ruby 3.2's IRB?](https://st0012.dev/whats-new-in-ruby-3-2-irb)
+    * More Pry-like commands and features have been added.
+        * `edit` and `show_cmds` (like Pry's `help`) are added.
+        * `ls` takes `-g` or `-G` option to filter out outputs.
+        * `show_source` is aliased from `$` and accepts unquoted inputs.
+        * `whereami` is aliased from `@`.
+
+* Net::Protocol
+
+    * Improve `Net::BufferedIO` performance. [[GH-net-protocol-14]]
+
+* Pathname
+
+    * Added `Pathname#lutime`. [[GH-pathname-20]]
+
+* Socket
+
+    * Added the following constants for supported platforms.
+        * `SO_INCOMING_CPU`
+        * `SO_INCOMING_NAPI_ID`
+        * `SO_RTABLE`
+        * `SO_SETFIB`
+        * `SO_USER_COOKIE`
+        * `TCP_KEEPALIVE`
+        * `TCP_CONNECTION_INFO`
+
+* SyntaxSuggest
+
+    * The feature of `syntax_suggest` formerly `dead_end` is integrated in Ruby.
+      [[Feature #18159]]
+
+* UNIXSocket
+
+    * Add support for UNIXSocket on Windows. Emulate anonymous sockets. Add
+      support for File.socket? and File::Stat#socket? where possible.
+      [[Feature #19135]]
+
+*   The following default gems are updated.
+
+    * RubyGems 3.4.1
+    * abbrev 0.1.1
+    * benchmark 0.2.1
+    * bigdecimal 3.1.3
+    * bundler 2.4.1
+    * cgi 0.3.6
+    * csv 3.2.6
+    * date 3.3.3
+    * delegate 0.3.0
+    * did_you_mean 1.6.3
+    * digest 3.1.1
+    * drb 2.1.1
+    * english 0.7.2
+    * erb 4.0.2
+    * error_highlight 0.5.1
+    * etc 1.4.2
+    * fcntl 1.0.2
+    * fiddle 1.1.1
+    * fileutils 1.7.0
+    * forwardable 1.3.3
+    * getoptlong 0.2.0
+    * io-console 0.6.0
+    * io-nonblock 0.2.0
+    * io-wait 0.3.0
+    * ipaddr 1.2.5
+    * irb 1.6.2
+    * json 2.6.3
+    * logger 1.5.3
+    * mutex_m 0.1.2
+    * net-http 0.4.0
+    * net-protocol 0.2.1
+    * nkf 0.1.2
+    * open-uri 0.3.0
+    * open3 0.1.2
+    * openssl 3.1.0
+    * optparse 0.3.1
+    * ostruct 0.5.5
+    * pathname 0.2.1
+    * pp 0.4.0
+    * pstore 0.1.2
+    * psych 5.0.1
+    * racc 1.6.2
+    * rdoc 6.5.0
+    * readline-ext 0.1.5
+    * reline 0.3.2
+    * resolv 0.2.2
+    * resolv-replace 0.1.1
+    * securerandom 0.2.2
+    * set 1.0.3
+    * stringio 3.0.4
+    * strscan 3.0.5
+    * syntax_suggest 1.0.2
+    * syslog 0.1.1
+    * tempfile 0.1.3
+    * time 0.2.1
+    * timeout 0.3.1
+    * tmpdir 0.1.3
+    * tsort 0.1.1
+    * un 0.2.1
+    * uri 0.12.0
+    * weakref 0.1.2
+    * win32ole 1.8.9
+    * yaml 0.2.1
+    * zlib 3.0.0
+
+*   The following bundled gems are updated.
+
+    * minitest 5.16.3
+    * power_assert 2.0.3
+    * test-unit 3.5.7
+    * net-ftp 0.2.0
+    * net-imap 0.3.4
+    * net-pop 0.1.2
+    * net-smtp 0.3.3
+    * rbs 2.8.2
+    * typeprof 0.21.3
+    * debug 1.7.1
+
+See GitHub releases like [GitHub Releases of Logger](https://github.com/ruby/logger/releases) or changelog for details of the default gems or bundled gems.
+
+## Supported platforms
+
+* WebAssembly/WASI is added. See [wasm/README.md] and [ruby.wasm] for more details. [[Feature #18462]]
+
+## Compatibility issues
+
+* `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
+
+The following deprecated constants are removed.
+
+* `Fixnum` and `Bignum` [[Feature #12005]]
+* `Random::DEFAULT` [[Feature #17351]]
+* `Struct::Group`
+* `Struct::Passwd`
+
+### Removed methods
+
+The following deprecated methods are removed.
+
+* `Dir.exists?` [[Feature #17391]]
+* `File.exists?` [[Feature #17391]]
+* `Kernel#=~` [[Feature #15231]]
+* `Kernel#taint`, `Kernel#untaint`, `Kernel#tainted?`
+  [[Feature #16131]]
+* `Kernel#trust`, `Kernel#untrust`, `Kernel#untrusted?`
+  [[Feature #16131]]
+* `Method#public?`, `Method#private?`, `Method#protected?`,
+  `UnboundMethod#public?`, `UnboundMethod#private?`, `UnboundMethod#protected?`
+  [[Bug #18729]] [[Bug #18751]] [[Bug #18435]]
+
+### Source code incompatibility of extension libraries
+
+* Extension libraries provide PRNG, subclasses of Random, need updates.
+  See [PRNG update] below for more information. [[Bug #19100]]
+
+### Error printer
+
+* Ruby no longer escapes control characters and backslashes in an
+  error message. [[Feature #18367]]
+
+### Constant lookup when defining a class/module
+
+* When defining a class/module directly under the Object class by class/module
+  statement, if there is already a class/module defined by `Module#include`
+  with the same name, the statement was handled as "open class" in Ruby 3.1 or before.
+  Since Ruby 3.2, a new class is defined instead. [[Feature #18832]]
+
+## Stdlib compatibility issues
+
+* Psych no longer bundles libyaml sources.
+  And also Fiddle no longer bundles libffi sources.
+  Users need to install the libyaml/libffi library themselves via the package
+  manager like apt, yum, brew, etc.
+
+    Psych and fiddle supported the static build with specific version of libyaml
+    and libffi sources. You can build psych with libyaml-0.2.5 like this.
+
+    ```bash
+    $ ./configure --with-libyaml-source-dir=/path/to/libyaml-0.2.5
+    ```
+
+    And you can build fiddle with libffi-3.4.4 like this.
+
+    ```bash
+    $ ./configure --with-libffi-source-dir=/path/to/libffi-3.4.4
+    ```
+
+    [[Feature #18571]]
+
+* Check cookie name/path/domain characters in `CGI::Cookie`. [[CVE-2021-33621]]
+
+* `URI.parse` return empty string in host instead of nil. [[sec-156615]]
+
+## C API updates
+
+### Updated C APIs
+
+The following APIs are updated.
+
+* PRNG update
+
+    `rb_random_interface_t` in ruby/random.h updated and versioned.
+    Extension libraries which use this interface and built for older
+    versions need to rebuild with adding `init_int32` function.
+
+### Added C APIs
+
+* `VALUE rb_hash_new_capa(long capa)` was added to created hashes with the desired capacity.
+* `rb_internal_thread_add_event_hook` and `rb_internal_thread_add_event_hook` were added to instrument threads scheduling.
+  The following events are available:
+    * `RUBY_INTERNAL_THREAD_EVENT_STARTED`
+    * `RUBY_INTERNAL_THREAD_EVENT_READY`
+    * `RUBY_INTERNAL_THREAD_EVENT_RESUMED`
+    * `RUBY_INTERNAL_THREAD_EVENT_SUSPENDED`
+    * `RUBY_INTERNAL_THREAD_EVENT_EXITED`
+* `rb_debug_inspector_current_depth` and `rb_debug_inspector_frame_depth` are added for debuggers.
+
+### Removed C APIs
+
+The following deprecated APIs are removed.
+
+* `rb_cData` variable.
+* "taintedness" and "trustedness" functions. [[Feature #16131]]
+
+## Implementation improvements
+
+* Fixed several race conditions in Kernel#autoload. [[Bug #18782]]
+* Cache invalidation for expressions referencing constants is now
+  more fine-grained. `RubyVM.stat(:global_constant_state)` was
+  removed because it was closely tied to the previous caching scheme
+  where setting any constant invalidates all caches in the system.
+  New keys, `:constant_cache_invalidations` and `:constant_cache_misses`,
+  were introduced to help with use cases for `:global_constant_state`.
+  [[Feature #18589]]
+* The cache-based optimization for Regexp matching is introduced.
+  [[Feature #19104]]
+* [Variable Width Allocation](https://shopify.engineering/ruby-variable-width-allocation)
+  is now enabled by default. [[Feature #18239]]
+* Added a new instance variable caching mechanism, called object shapes, which
+  improves inline cache hits for most objects and allows us to generate very
+  efficient JIT code. Objects whose instance variables are defined in a
+  consistent order will see the most performance benefits.
+  [[Feature #18776]]
+* Speed up marking instruction sequences by using a bitmap to find "markable"
+  objects.  This change results in faster major collections.
+  [[Feature #18875]]
+
+## JIT
+
+### YJIT
+
+* YJIT is no longer experimental
+    * Has been tested on production workloads for over a year and proven to be quite stable.
+* YJIT now supports both x86-64 and arm64/aarch64 CPUs on Linux, MacOS, BSD and other UNIX platforms.
+    * This release brings support for Mac M1/M2, AWS Graviton and Raspberry Pi 4.
+* Building YJIT now requires Rust 1.58.0+. [[Feature #18481]]
+    * In order to ensure that CRuby is built with YJIT, please install `rustc` >= 1.58.0
+      before running `./configure`
+    * Please reach out to the YJIT team should you run into any issues.
+* Physical memory for JIT code is lazily allocated. Unlike Ruby 3.1,
+  the RSS of a Ruby process is minimized because virtual memory pages
+  allocated by `--yjit-exec-mem-size` will not be mapped to physical
+  memory pages until actually utilized by JIT code.
+* Introduce Code GC that frees all code pages when the memory consumption
+  by JIT code reaches `--yjit-exec-mem-size`.
+    * `RubyVM::YJIT.runtime_stats` returns Code GC metrics in addition to
+      existing `inline_code_size` and `outlined_code_size` keys:
+      `code_gc_count`, `live_page_count`, `freed_page_count`, and `freed_code_size`.
+* Most of the statistics produced by `RubyVM::YJIT.runtime_stats` are now available in release builds.
+    * Simply run ruby with `--yjit-stats` to compute and dump stats (incurs some run-time overhead).
+* YJIT is now optimized to take advantage of object shapes. [[Feature #18776]]
+* Take advantage of finer-grained constant invalidation to invalidate less code when defining new constants. [[Feature #18589]]
+* The default `--yjit-exec-mem-size` is changed to 64 (MiB).
+* The default `--yjit-call-threshold` is changed to 30.
+
+### MJIT
+
+* The MJIT compiler is re-implemented in Ruby as `ruby_vm/mjit/compiler`.
+* MJIT compiler is executed under a forked Ruby process instead of
+  doing it in a native thread called MJIT worker. [[Feature #18968]]
+    * As a result, Microsoft Visual Studio (MSWIN) is no longer supported.
+* MinGW is no longer supported. [[Feature #18824]]
+* Rename `--mjit-min-calls` to `--mjit-call-threshold`.
+* Change default `--mjit-max-cache` back from 10000 to 100.
+
+[Feature #12005]:     https://bugs.ruby-lang.org/issues/12005
+[Feature #12084]:     https://bugs.ruby-lang.org/issues/12084
+[Feature #12655]:     https://bugs.ruby-lang.org/issues/12655
+[Feature #12737]:     https://bugs.ruby-lang.org/issues/12737
+[Feature #13110]:     https://bugs.ruby-lang.org/issues/13110
+[Feature #14332]:     https://bugs.ruby-lang.org/issues/14332
+[Feature #15231]:     https://bugs.ruby-lang.org/issues/15231
+[Feature #15357]:     https://bugs.ruby-lang.org/issues/15357
+[Bug #15928]:         https://bugs.ruby-lang.org/issues/15928
+[Feature #16122]:     https://bugs.ruby-lang.org/issues/16122
+[Feature #16131]:     https://bugs.ruby-lang.org/issues/16131
+[Bug #16466]:         https://bugs.ruby-lang.org/issues/16466
+[Feature #16663]:     https://bugs.ruby-lang.org/issues/16663
+[Feature #16806]:     https://bugs.ruby-lang.org/issues/16806
+[Bug #16889]:         https://bugs.ruby-lang.org/issues/16889
+[Bug #16908]:         https://bugs.ruby-lang.org/issues/16908
+[Feature #16989]:     https://bugs.ruby-lang.org/issues/16989
+[Feature #17351]:     https://bugs.ruby-lang.org/issues/17351
+[Feature #17391]:     https://bugs.ruby-lang.org/issues/17391
+[Bug #17545]:         https://bugs.ruby-lang.org/issues/17545
+[Bug #17767]:         https://bugs.ruby-lang.org/issues/17767
+[Feature #17837]:     https://bugs.ruby-lang.org/issues/17837
+[Feature #17881]:     https://bugs.ruby-lang.org/issues/17881
+[Feature #18033]:     https://bugs.ruby-lang.org/issues/18033
+[Feature #18159]:     https://bugs.ruby-lang.org/issues/18159
+[Feature #18239]:     https://bugs.ruby-lang.org/issues/18239#note-17
+[Feature #18351]:     https://bugs.ruby-lang.org/issues/18351
+[Feature #18367]:     https://bugs.ruby-lang.org/issues/18367
+[Bug #18435]:         https://bugs.ruby-lang.org/issues/18435
+[Feature #18462]:     https://bugs.ruby-lang.org/issues/18462
+[Feature #18481]:     https://bugs.ruby-lang.org/issues/18481
+[Bug #18487]:         https://bugs.ruby-lang.org/issues/18487
+[Feature #18564]:     https://bugs.ruby-lang.org/issues/18564
+[Feature #18571]:     https://bugs.ruby-lang.org/issues/18571
+[Feature #18585]:     https://bugs.ruby-lang.org/issues/18585
+[Feature #18589]:     https://bugs.ruby-lang.org/issues/18589
+[Feature #18595]:     https://bugs.ruby-lang.org/issues/18595
+[Feature #18598]:     https://bugs.ruby-lang.org/issues/18598
+[Bug #18625]:         https://bugs.ruby-lang.org/issues/18625
+[Feature #18630]:     https://bugs.ruby-lang.org/issues/18630
+[Bug #18633]:         https://bugs.ruby-lang.org/issues/18633
+[Feature #18639]:     https://bugs.ruby-lang.org/issues/18639
+[Feature #18685]:     https://bugs.ruby-lang.org/issues/18685
+[Bug #18729]:         https://bugs.ruby-lang.org/issues/18729
+[Bug #18751]:         https://bugs.ruby-lang.org/issues/18751
+[Feature #18774]:     https://bugs.ruby-lang.org/issues/18774
+[Feature #18776]:     https://bugs.ruby-lang.org/issues/18776
+[Bug #18782]:         https://bugs.ruby-lang.org/issues/18782
+[Feature #18788]:     https://bugs.ruby-lang.org/issues/18788
+[Feature #18798]:     https://bugs.ruby-lang.org/issues/18798
+[Feature #18809]:     https://bugs.ruby-lang.org/issues/18809
+[Feature #18821]:     https://bugs.ruby-lang.org/issues/18821
+[Feature #18822]:     https://bugs.ruby-lang.org/issues/18822
+[Feature #18824]:     https://bugs.ruby-lang.org/issues/18824
+[Feature #18832]:     https://bugs.ruby-lang.org/issues/18832
+[Feature #18875]:     https://bugs.ruby-lang.org/issues/18875
+[Feature #18925]:     https://bugs.ruby-lang.org/issues/18925
+[Feature #18944]:     https://bugs.ruby-lang.org/issues/18944
+[Feature #18949]:     https://bugs.ruby-lang.org/issues/18949
+[Feature #18968]:     https://bugs.ruby-lang.org/issues/18968
+[Feature #19008]:     https://bugs.ruby-lang.org/issues/19008
+[Feature #19013]:     https://bugs.ruby-lang.org/issues/19013
+[Feature #19026]:     https://bugs.ruby-lang.org/issues/19026
+[Feature #19036]:     https://bugs.ruby-lang.org/issues/19036
+[Feature #19060]:     https://bugs.ruby-lang.org/issues/19060
+[Feature #19070]:     https://bugs.ruby-lang.org/issues/19070
+[Feature #19071]:     https://bugs.ruby-lang.org/issues/19071
+[Feature #19078]:     https://bugs.ruby-lang.org/issues/19078
+[Bug #19087]:         https://bugs.ruby-lang.org/issues/19087
+[Bug #19100]:         https://bugs.ruby-lang.org/issues/19100
+[Feature #19104]:     https://bugs.ruby-lang.org/issues/19104
+[Feature #19135]:     https://bugs.ruby-lang.org/issues/19135
+[Feature #19138]:     https://bugs.ruby-lang.org/issues/19138
+[Feature #19194]:     https://bugs.ruby-lang.org/issues/19194
+[Molinillo]:          https://github.com/CocoaPods/Molinillo
+[PubGrub]:            https://github.com/jhawthorn/pub_grub
+[GH-net-protocol-14]: https://github.com/ruby/net-protocol/pull/14
+[GH-pathname-20]:     https://github.com/ruby/pathname/pull/20
+[GH-6791]:            https://github.com/ruby/ruby/pull/6791
+[GH-6868]:            https://github.com/ruby/ruby/pull/6868
+[GH-rubygems-4475]:   https://github.com/rubygems/rubygems/pull/4475
+[GH-rubygems-6149]:   https://github.com/rubygems/rubygems/pull/6149
+[GH-rubygems-6167]:   https://github.com/rubygems/rubygems/pull/6167
+[sec-156615]:         https://hackerone.com/reports/156615
+[CVE-2021-33621]:     https://www.ruby-lang.org/en/news/2022/11/22/http-response-splitting-in-cgi-cve-2021-33621/
+[wasm/README.md]:     https://github.com/ruby/ruby/blob/master/wasm/README.md
+[ruby.wasm]:          https://github.com/ruby/ruby.wasm
diff --git a/README.ja.md b/README.ja.md
index 9d6131e416..93c0131690 100644
--- a/README.ja.md
+++ b/README.ja.md
@@ -1,3 +1,10 @@
+[![Actions Status: MinGW](https://github.com/ruby/ruby/workflows/MinGW/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"MinGW")
+[![Actions Status: MJIT](https://github.com/ruby/ruby/workflows/MJIT/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"MJIT")
+[![Actions Status: Ubuntu](https://github.com/ruby/ruby/workflows/Ubuntu/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"Ubuntu")
+[![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)
+
 # Ruby��
 
 Ruby�シンプル��強力�オブジェクト指�スクリプト言語��． Ruby�純粋�オブジェクト指�言語���設計�れ��る��，
@@ -10,83 +17,86 @@ Ruby�テキスト処�関係�能力���優れ，Perl����ら�
 
 *   シンプル�文法
 *   普通�オブジェクト指�機能(クラス，メソッドコール��)
-*   特殊�オブジェクト指�機能(Mixin, 特異メソッド��)
+*   特殊�オブジェクト指�機能(Mixin，特異メソッド��)
 *   演算�オー�ーロード
 *   例外処�機能
 *   イテレータ�クロージャ
 *   ガーベージコレクタ
 *   ダイナミックローディング (アーキテク�ャ�よる)
-*   移�性�高�．多��Unix-like/POSIX互�プラットフォーム上�動������，Windows， Mac OS
-    X，BeOS���上�も動� cf.
-    http://bugs.ruby-lang.org/projects/ruby-trunk/wiki/SupportedPlatformsJa
+*   移�性�高�．多��Unix-like/POSIX互�プラットフォーム上�動������，Windows， macOS，
+    Haiku���上�も動� cf.
+    https://github.com/ruby/ruby/blob/master/doc/contributing.rdoc#platform-maintainers
 
 
 ## 入手法
 
-### FTP�
+サードパーティーツールを使��方法を�むRuby�インストール方法�一覧�
+
+https://www.ruby-lang.org/ja/downloads/
+
+を�照������．
 
-以下�場所�����り��．
+### Git
 
-ftp://ftp.ruby-lang.org/pub/ruby/
+ミラーをGitHub�公開�����． 以下�コマンド�リ�ジトリを�得����．
 
-### Subversion�
+    $ git clone https://github.com/ruby/ruby.git
 
-開発先端�ソースコード�次�コマンド��得����．
+他�ブラン��一覧�次�コマンド�見られ��．
 
-    $ svn co http://svn.ruby-lang.org/repos/ruby/trunk/ ruby
+    $ git ls-remote https://github.com/ruby/ruby.git
 
-他�開発中�ブラン��一覧�次�コマンド�見られ��．
+Rubyリ�ジトリ�本��master� https://git.ruby-lang.org/ruby.git ��り��．
+コミッタ���らを使���．
 
-    $ svn ls http://svn.ruby-lang.org/repos/ruby/branches/
+### Subversion
 
-### Git�
+��Ruby��ージョン�ソースコード�次�コマンド�も�得����．
 
-Subversion�ミラーをGitHub�公開�����． 以下�コマンド�リ�ジトリを�得����．
+    $ svn co https://svn.ruby-lang.org/repos/ruby/branches/ruby_2_6/ ruby
+
+他�ブラン��一覧�次�コマンド�見られ��．
+
+    $ svn ls https://svn.ruby-lang.org/repos/ruby/branches/
 
-    $ git clone git://github.com/ruby/ruby.git
 
 ## ホームページ
 
 Ruby�ホームページ�URL�
 
-http://www.ruby-lang.org/
+https://www.ruby-lang.org/
 
 ��．
 
 ## メーリングリスト
 
-Ruby�メーリングリスト��り��．�加希望�方�
-
-mailto:ruby-list-request@ruby-lang.org
-
-��本文�
+Ruby�メーリングリスト��り��．�加希望�方� [ruby-list-request@ruby-lang.org] ��本文�
 
     subscribe
 
 �書�����下��．
 
-Ruby開発者��メーリングリストも�り��．��ら��ruby��グ，将��仕様拡張��実装上��題����議論�れ����． �加希望�方�
-
-mailto:ruby-dev-request@ruby-lang.org
-
-��ruby-list��様�方法�メール������．
+Ruby開発者��メーリングリストも�り��．��ら��ruby��グ，将��仕様拡張��実装上��題����議論�れ����．
+�加希望�方� [ruby-dev-request@ruby-lang.org] ��ruby-list��様�方法�メール������．
 
 Ruby拡張モジュール����話���ruby-extメーリングリスト�数学関係�話題����話���ruby-mathメーリングリスト�
 英語�ruby����話���ruby-talkメーリングリストも�り��．�加方法��れも����．
 
+[ruby-list-request@ruby-lang.org]: mailto:ruby-list-request@ruby-lang.org?subject=Join%20Ruby%20Mailing%20List&body=subscribe
+[ruby-dev-request@ruby-lang.org]: mailto:ruby-dev-request@ruby-lang.org?subject=Join%20Ruby%20Mailing%20List&body=subscribe
+
 ## コンパイル・インストール
 
 以下�手順�行������．
 
-1.  も� `configure` ファイル�見��ら��，も��� `configure.in` より��よ��ら， `autoconf` を実行��
-    新�� `configure` を生��る
+1.  (Gitリ�ジトリ�ら�得��ソースをビルド�る場�) `./autogen.sh` を実行��新�� `configure` を生��る
 
 2.  `configure` を実行�� `Makefile` ��を生��る
 
     環境�よ���デフォルト�Cコンパイラ用オプション�付���． `configure` オプション� `optflags=..`
     `warnflags=..` 等�上書�����．
 
-3.  (必��ら�)`defines.h` を編集�る
+3.  (必��ら�)`include/ruby/defines.h` を編集�る
 
     多分，必�無������．
 
@@ -95,7 +105,8 @@ Ruby拡張モジュールã�«ã�¤ã�„ã�¦è©±ã�—å�ˆã�†ruby-extメーリングリスãƒ
     `ext/Setup` �記述��モジュール��的�リンク�れ��．
 
     ダイナミックローディングをサ�ート�����アーキテク�ャ�� `Setup` �1行目�「`option nodynamic`����行�コ
-    メントを外�必���り��．��，��アーキテク�ャ�拡張モジュールを利用�る����，�ら����的�リンクを����必���り��．
+    メントを外�必���り��．
+    ��，��アーキテク�ャ�拡張モジュールを利用�る����，�ら����的�リンクを����必���り��．
 
 5.  `make` を実行��コンパイル�る
 
@@ -155,17 +166,17 @@ UNIX��れ� `configure` ���ん��差異を�����れる�
 
 ## フィード�ック
 
-Ruby�関�る質�� Ruby-Talk（英語）や Ruby-List（日本語） (https://www.ruby-lang.org/ja/community/mailing-lists) や，
-stackoverflow (http://ja.stackoverflow.com/) ���Webサイト�投稿������．
+Ruby�関�る質�� [Ruby-Talk]（英語）や [Ruby-List]（日本語）や，
+[stackoverflow] ���Webサイト�投稿������．
 
-�グ報告� http://bugs.ruby-lang.org ���付�����．
+�グ報告� https://bugs.ruby-lang.org ���付�����．
 
+[Ruby-Talk]: https://www.ruby-lang.org/en/community/mailing-lists
+[Ruby-List]: https://www.ruby-lang.org/ja/community/mailing-lists
+[stackoverflow]: https://ja.stackoverflow.com/
 
 ## 著者
 
 Ruby�オリジナル版�，1995年���も�ゆ�����よ��設計・開発�れ���．
 
 <mailto:matz@ruby-lang.org>
-
----
-created at: Thu Aug  3 11:57:36 JST 1995
diff --git a/README.md b/README.md
index f79ba9c718..c445448c71 100644
--- a/README.md
+++ b/README.md
@@ -1,167 +1,91 @@
-[![Build Status](https://travis-ci.org/ruby/ruby.svg)](https://travis-ci.org/ruby/ruby)
-[![Build status](https://ci.appveyor.com/api/projects/status/0sy8rrxut4o0k960/branch/trunk?svg=true)](https://ci.appveyor.com/project/ruby/ruby/branch/trunk)
+[![Actions Status: MinGW](https://github.com/ruby/ruby/workflows/MinGW/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"MinGW")
+[![Actions Status: MJIT](https://github.com/ruby/ruby/workflows/MJIT/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"MJIT")
+[![Actions Status: Ubuntu](https://github.com/ruby/ruby/workflows/Ubuntu/badge.svg)](https://github.com/ruby/ruby/actions?query=workflow%3A"Ubuntu")
+[![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)
 
-# What's Ruby
+# What is Ruby?
 
-Ruby is the interpreted scripting language for quick and easy object-oriented
-programming.  It has many features to process text files and to do system
-management tasks (as in Perl).  It is simple, straight-forward, and
-extensible.
+Ruby is an interpreted object-oriented programming language often
+used for web development. It also offers many scripting features
+to process plain text and serialized files, or manage system tasks.
+It is simple, straightforward, and extensible.
 
 ## Features of Ruby
 
-*   Simple Syntax
-*   **Normal** Object-oriented Features (e.g. class, method calls)
-*   **Advanced** Object-oriented Features (e.g. Mix-in, Singleton-method)
-*   Operator Overloading
-*   Exception Handling
-*   Iterators and Closures
-*   Garbage Collection
-*   Dynamic Loading of Object Files (on some architectures)
-*   Highly Portable (works on many Unix-like/POSIX compatible platforms as
-    well as Windows, Mac OS X, BeOS, etc.) cf.
-    http://bugs.ruby-lang.org/projects/ruby-trunk/wiki/SupportedPlatforms
+* Simple Syntax
+* **Normal** Object-oriented Features (e.g. class, method calls)
+* **Advanced** Object-oriented Features (e.g. mix-in, singleton-method)
+* Operator Overloading
+* Exception Handling
+* Iterators and Closures
+* Garbage Collection
+* Dynamic Loading of Object Files (on some architectures)
+* Highly Portable (works on many Unix-like/POSIX compatible platforms as
+  well as Windows, macOS, etc.) cf.
+  https://github.com/ruby/ruby/blob/master/doc/maintainers.rdoc#label-Platform+Maintainers
 
-
-## How to get Ruby
+## How to get Ruby with Git
 
 For a complete list of ways to install Ruby, including using third-party tools
 like rvm, see:
 
-http://www.ruby-lang.org/en/downloads/
-
-The Ruby distribution files can be found on the following FTP site:
-
-ftp://ftp.ruby-lang.org/pub/ruby/
-
-The trunk of the Ruby source tree can be checked out with the following
-command:
+https://www.ruby-lang.org/en/downloads/
 
-    $ svn co http://svn.ruby-lang.org/repos/ruby/trunk/ ruby
+The mirror of the Ruby source tree can be checked out with the following command:
 
-Or if you are using git then use the following command:
+    $ git clone https://github.com/ruby/ruby.git
 
-    $ git clone git://github.com/ruby/ruby.git
-
-There are some other branches under development.  Try the following command
+There are some other branches under development. Try the following command
 to see the list of branches:
 
-    $ svn ls http://svn.ruby-lang.org/repos/ruby/branches/
+    $ git ls-remote https://github.com/ruby/ruby.git
+
+You may also want to use https://git.ruby-lang.org/ruby.git (actual master of Ruby source)
+if you are a committer.
 
-Or if you are using git then use the following command:
+## How to build
 
-    $ git ls-remote git://github.com/ruby/ruby.git
+see [Building Ruby](doc/contributing/building_ruby.md)
 
 ## Ruby home page
 
-The URL of the Ruby home page is:
+https://www.ruby-lang.org/
 
-http://www.ruby-lang.org/
+## Documentation
+
+- [English](https://docs.ruby-lang.org/en/master/index.html)
+- [Japanese](https://docs.ruby-lang.org/ja/master/index.html)
 
 ## Mailing list
 
-There is a mailing list to talk about Ruby. To subscribe to this list, please
+There is a mailing list to discuss Ruby. To subscribe to this list, please
 send the following phrase:
 
     subscribe
 
-in the mail body (not subject) to the address
-<mailto:ruby-talk-request@ruby-lang.org>.
-
-## How to compile and install
-
-This is what you need to do to compile and install Ruby:
-
-1.  If you want to use Microsoft Visual C++ to compile ruby, read
-    win32/README.win32 instead of this document.
-
-2.  If `./configure` does not exist or is older than configure.in, run
-    `autoconf` to (re)generate configure.
-
-3.  Run `./configure`, which will generate `config.h` and `Makefile`.
-
-    Some C compiler flags may be added by default depending on your
-    environment.  Specify `optflags=..` and `warnflags=..` as necessary to
-    override them.
-
-4.  Edit `defines.h` if you need. Usually this step will not be needed.
-
-5.  Remove comment mark(`#`) before the module names from `ext/Setup` (or add
-    module names if not present), if you want to link modules statically.
+in the mail body (not subject) to the address [ruby-talk-request@ruby-lang.org].
 
-    If you don't want to compile non static extension modules (probably on
-    architectures which do not allow dynamic loading), remove comment mark
-    from the line "`#option nodynamic`" in `ext/Setup`.
-
-    Usually this step will not be needed.
-
-6.  Run `make`.
-
-7.  Optionally, run '`make check`' to check whether the compiled Ruby
-    interpreter works well. If you see the message "`check succeeded`", your
-    ruby works as it should (hopefully).
-
-8.  Run '`make install`'
-
-    This command will create the following directories and install files into
-    them.
-
-    *   `${DESTDIR}${prefix}/bin`
-    *   `${DESTDIR}${prefix}/include/ruby-${MAJOR}.${MINOR}.${TEENY}`
-    *   `${DESTDIR}${prefix}/include/ruby-${MAJOR}.${MINOR}.${TEENY}/${PLATFORM}`
-    *   `${DESTDIR}${prefix}/lib`
-    *   `${DESTDIR}${prefix}/lib/ruby`
-    *   `${DESTDIR}${prefix}/lib/ruby/${MAJOR}.${MINOR}.${TEENY}`
-    *   `${DESTDIR}${prefix}/lib/ruby/${MAJOR}.${MINOR}.${TEENY}/${PLATFORM}`
-    *   `${DESTDIR}${prefix}/lib/ruby/site_ruby`
-    *   `${DESTDIR}${prefix}/lib/ruby/site_ruby/${MAJOR}.${MINOR}.${TEENY}`
-    *   `${DESTDIR}${prefix}/lib/ruby/site_ruby/${MAJOR}.${MINOR}.${TEENY}/${PLATFORM}`
-    *   `${DESTDIR}${prefix}/lib/ruby/vendor_ruby`
-    *   `${DESTDIR}${prefix}/lib/ruby/vendor_ruby/${MAJOR}.${MINOR}.${TEENY}`
-    *   `${DESTDIR}${prefix}/lib/ruby/vendor_ruby/${MAJOR}.${MINOR}.${TEENY}/${PLATFORM}`
-    *   `${DESTDIR}${prefix}/lib/ruby/gems/${MAJOR}.${MINOR}.${TEENY}`
-    *   `${DESTDIR}${prefix}/share/man/man1`
-    *   `${DESTDIR}${prefix}/share/ri/${MAJOR}.${MINOR}.${TEENY}/system`
-
-
-    If Ruby's API version is '*x.y.z*', the `${MAJOR}` is '*x*', the
-    `${MINOR}` is '*y*', and the `${TEENY}` is '*z*'.
-
-    **NOTE**: teeny of the API version may be different from one of Ruby's
-    program version
-
-    You may have to be a super user to install ruby.
-
-
-If you fail to compile ruby, please send the detailed error report with the
-error log and machine/OS type, to help others.
-
-Some extension libraries may not get compiled because of lack of necessary
-external libraries and/or headers, then you will need to run '`make distclean-ext`'
-to remove old configuration after installing them in such case.
+[ruby-talk-request@ruby-lang.org]: mailto:ruby-talk-request@ruby-lang.org?subject=Join%20Ruby%20Mailing%20List&body=subscribe
 
 ## Copying
 
-See the file [COPYING](COPYING).
+See the file [COPYING](rdoc-ref:COPYING).
 
 ## Feedback
 
-Questions about the Ruby language can be asked on the Ruby-Talk mailing list
-(http://www.ruby-lang.org/en/community/mailing-lists) or on websites like
-(http://stackoverflow.com).
-
-Bug reports should be filed at http://bugs.ruby-lang.org. Read [HowToReport] for more information.
-
-[HowToReport]: https://bugs.ruby-lang.org/projects/ruby/wiki/HowToReport
+Questions about the Ruby language can be asked on the [Ruby-Talk](https://www.ruby-lang.org/en/community/mailing-lists) mailing list
+or on websites like https://stackoverflow.com.
 
-##Contributing
+Bugs should be reported at https://bugs.ruby-lang.org. Read ["Reporting Issues"](https://docs.ruby-lang.org/en/master/contributing/reporting_issues_md.html) for more information.
 
-See the file [CONTRIBUTING.md](CONTRIBUTING.md)
+## Contributing
 
+See ["Contributing to Ruby"](https://docs.ruby-lang.org/en/master/contributing_md.html), which includes setup and build instructions.
 
 ## The Author
 
-Ruby was originally designed and developed by Yukihiro Matsumoto (Matz) in
-1995.
+Ruby was originally designed and developed by Yukihiro Matsumoto (Matz) in 1995.
 
-<mailto:matz@ruby-lang.org>
+<matz@ruby-lang.org>
diff --git a/acinclude.m4 b/acinclude.m4
deleted file mode 100644
index 99b24e6d93..0000000000
--- a/acinclude.m4
+++ /dev/null
@@ -1,46 +0,0 @@
-# -*- autoconf -*-
-
-AC_DEFUN([_COLORIZE_RESULT_PREPARE], [
-    msg_checking= msg_result_yes= msg_result_no= msg_result_other= msg_reset=
-    AS_IF([test "x${CONFIGURE_TTY}" = xyes -o -t 1], [
-	msg_begin="`tput smso 2>/dev/null`"
-	AS_CASE(["$msg_begin"], ['@<:@'*m],
-	    [msg_begin="`echo "$msg_begin" | sed ['s/[0-9]*m$//']`"
-	    msg_checking="${msg_begin}33m"
-	    AS_IF([test ${TEST_COLORS:+set}], [
-		msg_result_yes=[`expr ":$TEST_COLORS:" : ".*:pass=\([^:]*\):"`]
-		msg_result_no=[`expr ":$TEST_COLORS:" : ".*:fail=\([^:]*\):"`]
-		msg_result_other=[`expr ":$TEST_COLORS:" : ".*:skip=\([^:]*\):"`]
-	    ])
-	    msg_result_yes="${msg_begin}${msg_result_yes:-32;1}m"
-	    msg_result_no="${msg_begin}${msg_result_no:-31;1}m"
-	    msg_result_other="${msg_begin}${msg_result_other:-33;1}m"
-	    msg_reset="${msg_begin}m"
-	    ])
-	AS_UNSET(msg_begin)
-	])
-    AS_REQUIRE_SHELL_FN([colorize_result],
-	[AS_FUNCTION_DESCRIBE([colorize_result], [MSG], [Colorize result])],
-        [AS_CASE(["$[]1"],
-            [yes], [AS_ECHO(["${msg_result_yes}$[]1${msg_reset}]")],
-            [no], [AS_ECHO(["${msg_result_no}$[]1${msg_reset}]")],
-            [AS_ECHO(["${msg_result_other}$[]1${msg_reset}]")])])
-])
-
-AC_DEFUN([COLORIZE_RESULT], [AC_REQUIRE([_COLORIZE_RESULT_PREPARE])dnl
-    AS_LITERAL_IF([$1],
-	[m4_case([$1],
-		[yes], [AS_ECHO(["${msg_result_yes}$1${msg_reset}"])],
-		[no], [AS_ECHO(["${msg_result_no}$1${msg_reset}"])],
-		[AS_ECHO(["${msg_result_other}$1${msg_reset}"])])],
-	[colorize_result "$1"]) dnl
-])
-
-AC_DEFUN([AC_CHECKING],[dnl
-AC_REQUIRE([_COLORIZE_RESULT_PREPARE])dnl
-AS_MESSAGE([checking ${msg_checking}$1${msg_reset}...])])
-
-AC_DEFUN([AC_MSG_RESULT], [dnl
-{ _AS_ECHO_LOG([result: $1])
-COLORIZE_RESULT([$1]); dnl
-}])
diff --git a/aclocal.m4 b/aclocal.m4
index 56e944be8f..e69de29bb2 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -1,15 +0,0 @@
-# generated automatically by aclocal 1.15 -*- Autoconf -*-
-
-# Copyright (C) 1996-2014 Free Software Foundation, Inc.
-
-# This file is free software; the Free Software Foundation
-# gives unlimited permission to copy and/or distribute it,
-# with or without modifications, as long as this notice is preserved.
-
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY, to the extent permitted by law; without
-# even the implied warranty of MERCHANTABILITY or FITNESS FOR A
-# PARTICULAR PURPOSE.
-
-m4_ifndef([AC_CONFIG_MACRO_DIRS], [m4_defun([_AM_CONFIG_MACRO_DIRS], [])m4_defun([AC_CONFIG_MACRO_DIRS], [_AM_CONFIG_MACRO_DIRS($@)])])
-m4_include([acinclude.m4])
diff --git a/addr2line.c b/addr2line.c
index a20e5000c4..e5f25293e2 100644
--- a/addr2line.c
+++ b/addr2line.c
@@ -8,14 +8,26 @@
 
 **********************************************************************/
 
-#include "ruby/config.h"
+#if defined(__clang__)
+#pragma clang diagnostic ignored "-Wgnu-empty-initializer"
+#pragma clang diagnostic ignored "-Wgcc-compat"
+#endif
+
+#include "ruby/internal/config.h"
+#include "ruby/defines.h"
 #include "ruby/missing.h"
 #include "addr2line.h"
 
 #include <stdio.h>
 #include <errno.h>
 
-#ifdef USE_ELF
+#ifdef HAVE_LIBPROC_H
+#include <libproc.h>
+#endif
+
+#include "ruby/internal/stdbool.h"
+
+#if defined(USE_ELF) || defined(HAVE_MACH_O_LOADER_H)
 
 #include <fcntl.h>
 #include <limits.h>
@@ -28,12 +40,6 @@
 #include <sys/stat.h>
 #include <unistd.h>
 
-#ifdef __OpenBSD__
-#include <elf_abi.h>
-#else
-#include <elf.h>
-#endif
-
 /* Make alloca work the best possible way.  */
 #ifdef __GNUC__
 # ifndef alloca
@@ -57,24 +63,20 @@ void *alloca();
 # include <dlfcn.h>
 #endif
 
-#define DW_LNS_copy                     0x01
-#define DW_LNS_advance_pc               0x02
-#define DW_LNS_advance_line             0x03
-#define DW_LNS_set_file                 0x04
-#define DW_LNS_set_column               0x05
-#define DW_LNS_negate_stmt              0x06
-#define DW_LNS_set_basic_block          0x07
-#define DW_LNS_const_add_pc             0x08
-#define DW_LNS_fixed_advance_pc         0x09
-#define DW_LNS_set_prologue_end         0x0a /* DWARF3 */
-#define DW_LNS_set_epilogue_begin       0x0b /* DWARF3 */
-#define DW_LNS_set_isa                  0x0c /* DWARF3 */
+#ifdef HAVE_MACH_O_LOADER_H
+# include <crt_externs.h>
+# include <mach-o/fat.h>
+# include <mach-o/loader.h>
+# include <mach-o/nlist.h>
+# include <mach-o/stab.h>
+#endif
 
-/* Line number extended opcode name. */
-#define DW_LNE_end_sequence             0x01
-#define DW_LNE_set_address              0x02
-#define DW_LNE_define_file              0x03
-#define DW_LNE_set_discriminator        0x04  /* DWARF4 */
+#ifdef USE_ELF
+# ifdef __OpenBSD__
+#  include <elf_abi.h>
+# else
+#  include <elf.h>
+# endif
 
 #ifndef ElfW
 # if SIZEOF_VOIDP == 8
@@ -90,13 +92,44 @@ void *alloca();
 #  define ELF_ST_TYPE ELF32_ST_TYPE
 # endif
 #endif
+#endif
+
+#ifdef SHF_COMPRESSED
+# if defined(ELFCOMPRESS_ZLIB) && defined(HAVE_LIBZ)
+   /* FreeBSD 11.0 lacks ELFCOMPRESS_ZLIB */
+#  include <zlib.h>
+#  define SUPPORT_COMPRESSED_DEBUG_LINE
+# endif
+#else /* compatibility with glibc < 2.22 */
+# define SHF_COMPRESSED 0
+#endif
+
 #ifndef PATH_MAX
 #define PATH_MAX 4096
 #endif
 
-int kprintf(const char *fmt, ...);
+#define DW_LNS_copy                     0x01
+#define DW_LNS_advance_pc               0x02
+#define DW_LNS_advance_line             0x03
+#define DW_LNS_set_file                 0x04
+#define DW_LNS_set_column               0x05
+#define DW_LNS_negate_stmt              0x06
+#define DW_LNS_set_basic_block          0x07
+#define DW_LNS_const_add_pc             0x08
+#define DW_LNS_fixed_advance_pc         0x09
+#define DW_LNS_set_prologue_end         0x0a /* DWARF3 */
+#define DW_LNS_set_epilogue_begin       0x0b /* DWARF3 */
+#define DW_LNS_set_isa                  0x0c /* DWARF3 */
+
+/* Line number extended opcode name. */
+#define DW_LNE_end_sequence             0x01
+#define DW_LNE_set_address              0x02
+#define DW_LNE_define_file              0x03
+#define DW_LNE_set_discriminator        0x04  /* DWARF4 */
 
-typedef struct {
+PRINTF_ARGS(static int kprintf(const char *fmt, ...), 1, 2);
+
+typedef struct line_info {
     const char *dirname;
     const char *filename;
     const char *path; /* object path */
@@ -105,27 +138,72 @@ typedef struct {
     uintptr_t base_addr;
     uintptr_t saddr;
     const char *sname; /* function name */
+
+    struct line_info *next;
 } line_info_t;
-typedef struct obj_info obj_info_t;
-struct obj_info {
+
+struct dwarf_section {
+    char *ptr;
+    size_t size;
+    uint64_t flags;
+};
+
+typedef struct obj_info {
     const char *path; /* object path */
-    int fd;
-    void *mapped;
+    char *mapped;
     size_t mapped_size;
+    void *uncompressed;
     uintptr_t base_addr;
-    obj_info_t *next;
+    uintptr_t vmaddr;
+    struct dwarf_section debug_abbrev;
+    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 9
+
+static struct dwarf_section *
+obj_dwarf_section_at(obj_info_t *obj, int n)
+{
+    struct dwarf_section *ary[] = {
+        &obj->debug_abbrev,
+        &obj->debug_info,
+        &obj->debug_line,
+        &obj->debug_ranges,
+        &obj->debug_str_offsets,
+        &obj->debug_addr,
+        &obj->debug_rnglists,
+        &obj->debug_str,
+        &obj->debug_line_str
+    };
+    if (n < 0 || DWARF_SECTION_COUNT <= n) {
+        abort();
+    }
+    return ary[n];
+}
+
+struct debug_section_definition {
+    const char *name;
+    struct dwarf_section *dwarf;
 };
 
 /* Avoid consuming stack as this module may be used from signal handler */
-static char binary_filename[PATH_MAX];
+static char binary_filename[PATH_MAX + 1];
 
 static unsigned long
-uleb128(char **p)
+uleb128(const char **p)
 {
     unsigned long r = 0;
     int s = 0;
     for (;;) {
-	unsigned char b = *(unsigned char *)(*p)++;
+	unsigned char b = (unsigned char)*(*p)++;
 	if (b < 0x80) {
 	    r += (unsigned long)b << s;
 	    break;
@@ -137,12 +215,12 @@ uleb128(char **p)
 }
 
 static long
-sleb128(char **p)
+sleb128(const char **p)
 {
     long r = 0;
     int s = 0;
     for (;;) {
-	unsigned char b = *(unsigned char *)(*p)++;
+	unsigned char b = (unsigned char)*(*p)++;
 	if (b < 0x80) {
 	    if (b & 0x40) {
 		r -= (0x80 - b) << s;
@@ -159,7 +237,7 @@ sleb128(char **p)
 }
 
 static const char *
-get_nth_dirname(unsigned long dir, char *p)
+get_nth_dirname(unsigned long dir, const char *p)
 {
     if (!dir--) {
 	return "";
@@ -176,137 +254,191 @@ get_nth_dirname(unsigned long dir, 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, char *include_directories, char *filenames,
-	      line_info_t *line)
+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;
-    char *p = filenames;
-    char *filename;
+    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\n",
-		    file, binary_filename);
-	    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,
-	  char *include_directories, 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;
-    addr += obj->base_addr;
+    addr += obj->base_addr - obj->vmaddr;
     for (i = offset; i < num_traces; i++) {
 	uintptr_t a = (uintptr_t)traces[i];
 	/* 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]);
+	    fill_filename(file, format, version, include_directories, filenames, &lines[i], obj);
 	    lines[i].line = line;
 	}
     }
 }
 
-static void
-parse_debug_line_cu(int num_traces, void **traces, char **debug_line,
-		obj_info_t *obj, line_info_t *lines, int offset)
+struct LineNumberProgramHeader {
+    uint64_t unit_length;
+    uint16_t version;
+    uint8_t format; /* 4 or 8 */
+    uint64_t header_length;
+    uint8_t minimum_instruction_length;
+    uint8_t maximum_operations_per_instruction;
+    uint8_t default_is_stmt;
+    int8_t line_base;
+    uint8_t line_range;
+    uint8_t opcode_base;
+    /* uint8_t standard_opcode_lengths[opcode_base-1]; */
+    const char *include_directories;
+    const char *filenames;
+    const char *cu_start;
+    const char *cu_end;
+};
+
+static int
+parse_debug_line_header(obj_info_t *obj, const char **pp, struct LineNumberProgramHeader *header)
 {
-    char *p, *cu_end, *cu_start, *include_directories, *filenames;
-    unsigned long unit_length;
-    int default_is_stmt, line_base;
-    unsigned int header_length, minimum_instruction_length, line_range,
-		 opcode_base;
-    /* unsigned char *standard_opcode_lengths; */
+    const char *p = *pp;
+    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;
+    }
 
-    /* The registers. */
-    unsigned long addr = 0;
-    unsigned int file = 1;
-    unsigned int line = 1;
-    /* unsigned int column = 0; */
-    int is_stmt;
-    /* int basic_block = 0; */
-    /* int end_sequence = 0; */
-    /* int prologue_end = 0; */
-    /* int epilogue_begin = 0; */
-    /* unsigned int isa = 0; */
+    header->cu_end = p + header->unit_length;
 
-    p = *debug_line;
+    header->version = *(uint16_t *)p;
+    p += sizeof(uint16_t);
+    if (header->version > 5) return -1;
 
-    unit_length = *(unsigned int *)p;
-    p += sizeof(unsigned int);
-    if (unit_length == 0xffffffff) {
-	unit_length = *(unsigned long *)p;
-	p += sizeof(unsigned long);
+    if (header->version >= 5) {
+        /* address_size = *(uint8_t *)p++; */
+        /* segment_selector_size = *(uint8_t *)p++; */
+        p += 2;
     }
 
-    cu_end = p + unit_length;
-
-    /*dwarf_version = *(unsigned short *)p;*/
-    p += 2;
-
-    header_length = *(unsigned int *)p;
-    p += sizeof(unsigned int);
+    header->header_length = header->format == 4 ? *(uint32_t *)p : *(uint64_t *)p;
+    p += header->format;
+    header->cu_start = p + header->header_length;
 
-    cu_start = p + header_length;
+    header->minimum_instruction_length = *(uint8_t *)p++;
 
-    minimum_instruction_length = *(unsigned char *)p;
-    p++;
+    if (header->version >= 4) {
+        /* maximum_operations_per_instruction = *(uint8_t *)p; */
+        if (*p != 1) return -1; /* For non-VLIW architectures, this field is 1 */
+        p++;
+    }
 
-    is_stmt = default_is_stmt = *(unsigned char *)p;
-    p++;
+    header->default_is_stmt = *(uint8_t *)p++;
+    header->line_base = *(int8_t *)p++;
+    header->line_range = *(uint8_t *)p++;
+    header->opcode_base = *(uint8_t *)p++;
+    /* header->standard_opcode_lengths = (uint8_t *)p - 1; */
+    p += header->opcode_base - 1;
+
+    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;
 
-    line_base = *(signed char *)p;
-    p++;
+        /* temporary measure for compress-debug-sections */
+        if (p >= header->cu_end) return -1;
 
-    line_range = *(unsigned char *)p;
-    p++;
+        /* skip include directories */
+        while (*p) {
+            p = memchr(p, '\0', header->cu_end - p);
+            if (!p) return -1;
+            p++;
+        }
+        p++;
 
-    opcode_base = *(unsigned char *)p;
-    p++;
+        header->filenames = p;
+    }
 
-    /* standard_opcode_lengths = (unsigned char *)p - 1; */
-    p += opcode_base - 1;
+    *pp = header->cu_start;
 
-    include_directories = p;
+    return 0;
+}
 
-    /* skip include directories */
-    while (*p) {
-	while (*p) p++;
-	p++;
-    }
-    p++;
+static int
+parse_debug_line_cu(int num_traces, void **traces, const char **debug_line,
+		obj_info_t *obj, line_info_t *lines, int offset)
+{
+    const char *p = (const char *)*debug_line;
+    struct LineNumberProgramHeader header;
 
-    filenames = p;
+    /* The registers. */
+    unsigned long addr = 0;
+    unsigned int file = 1;
+    unsigned int line = 1;
+    /* unsigned int column = 0; */
+    int is_stmt;
+    /* int basic_block = 0; */
+    /* int end_sequence = 0; */
+    /* int prologue_end = 0; */
+    /* int epilogue_begin = 0; */
+    /* unsigned int isa = 0; */
 
-    p = cu_start;
+    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,		    \
-		  include_directories, filenames,		    \
+                  header.format,                                    \
+                  header.version,                                   \
+                  header.include_directories,                       \
+                  header.filenames,                                 \
 		  obj, lines, offset);				    \
 	/*basic_block = prologue_end = epilogue_begin = 0;*/	    \
     } while (0)
 
-    while (p < cu_end) {
+    while (p < header.cu_end) {
 	unsigned long a;
 	unsigned char op = *p++;
 	switch (op) {
@@ -314,7 +446,7 @@ parse_debug_line_cu(int num_traces, void **traces, char **debug_line,
 	    FILL_LINE();
 	    break;
 	case DW_LNS_advance_pc:
-	    a = uleb128(&p);
+	    a = uleb128(&p) * header.minimum_instruction_length;
 	    addr += a;
 	    break;
 	case DW_LNS_advance_line: {
@@ -335,12 +467,13 @@ parse_debug_line_cu(int num_traces, void **traces, char **debug_line,
 	    /*basic_block = 1; */
 	    break;
 	case DW_LNS_const_add_pc:
-	    a = ((255 - opcode_base) / line_range) *
-		minimum_instruction_length;
+	    a = ((255UL - header.opcode_base) / header.line_range) *
+		header.minimum_instruction_length;
 	    addr += a;
 	    break;
 	case DW_LNS_fixed_advance_pc:
-	    a = *(unsigned char *)p++;
+	    a = *(uint16_t *)p;
+	    p += sizeof(uint16_t);
 	    addr += a;
 	    break;
 	case DW_LNS_set_prologue_end:
@@ -353,7 +486,7 @@ parse_debug_line_cu(int num_traces, void **traces, char **debug_line,
 	    /* isa = (unsigned int)*/(void)uleb128(&p);
 	    break;
 	case 0:
-	    a = *(unsigned char *)p++;
+	    a = uleb128(&p);
 	    op = *p++;
 	    switch (op) {
 	    case DW_LNE_end_sequence:
@@ -363,7 +496,7 @@ parse_debug_line_cu(int num_traces, void **traces, char **debug_line,
 		file = 1;
 		line = 1;
 		/* column = 0; */
-		is_stmt = default_is_stmt;
+		is_stmt = header.default_is_stmt;
 		/* end_sequence = 0; */
 		/* isa = 0; */
 		break;
@@ -385,33 +518,34 @@ parse_debug_line_cu(int num_traces, void **traces, char **debug_line,
 	    }
 	    break;
 	default: {
-	    unsigned long addr_incr;
-	    unsigned long line_incr;
-	    a = op - opcode_base;
-	    addr_incr = (a / line_range) * minimum_instruction_length;
-	    line_incr = line_base + (a % line_range);
-	    addr += (unsigned int)addr_incr;
-	    line += (unsigned int)line_incr;
+            uint8_t adjusted_opcode = op - header.opcode_base;
+            uint8_t operation_advance = adjusted_opcode / header.line_range;
+            /* NOTE: this code doesn't support VLIW */
+            addr += operation_advance * header.minimum_instruction_length;
+            line += header.line_base + (adjusted_opcode % header.line_range);
 	    FILL_LINE();
 	}
 	}
     }
-    *debug_line = p;
+    *debug_line = (char *)p;
+    return 0;
 }
 
-static void
+static int
 parse_debug_line(int num_traces, void **traces,
-		 char *debug_line, unsigned long size,
+		 const char *debug_line, unsigned long size,
 		 obj_info_t *obj, line_info_t *lines, int offset)
 {
-    char *debug_line_end = debug_line + size;
+    const char *debug_line_end = debug_line + size;
     while (debug_line < debug_line_end) {
-	parse_debug_line_cu(num_traces, traces, &debug_line, obj, lines, offset);
+	if (parse_debug_line_cu(num_traces, traces, &debug_line, obj, lines, offset))
+	    return -1;
     }
     if (debug_line != debug_line_end) {
 	kprintf("Unexpected size of .debug_line in %s\n",
 		binary_filename);
     }
+    return 0;
 }
 
 /* read file and fill lines */
@@ -420,22 +554,38 @@ fill_lines(int num_traces, void **traces, int check_debuglink,
 	   obj_info_t **objp, line_info_t *lines, int offset);
 
 static void
-append_obj(obj_info_t **objp) {
+append_obj(obj_info_t **objp)
+{
     obj_info_t *newobj = calloc(1, sizeof(obj_info_t));
     if (*objp) (*objp)->next = newobj;
     *objp = newobj;
 }
 
+#ifdef USE_ELF
+/* Ideally we should check 4 paths to follow gnu_debuglink:
+ *
+ *   - /usr/lib/debug/.build-id/ab/cdef1234.debug
+ *   - /usr/bin/ruby.debug
+ *   - /usr/bin/.debug/ruby.debug
+ *   - /usr/lib/debug/usr/bin/ruby.debug.
+ *
+ * but we handle only two cases for now as the two formats are
+ * used by some linux distributions.
+ *
+ * See GDB's info for detail.
+ * https://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html
+ */
+
+// check the path pattern of "/usr/lib/debug/usr/bin/ruby.debug"
 static void
-follow_debuglink(char *debuglink, int num_traces, void **traces,
+follow_debuglink(const char *debuglink, int num_traces, void **traces,
 		 obj_info_t **objp, line_info_t *lines, int offset)
 {
-    /* Ideally we should check 4 paths to follow gnu_debuglink,
-       but we handle only one case for now as this format is used
-       by some linux distributions. See GDB's info for detail. */
     static const char global_debug_dir[] = "/usr/lib/debug";
-    char *p, *subdir;
+    const size_t global_debug_dir_len = sizeof(global_debug_dir) - 1;
+    char *p;
     obj_info_t *o1 = *objp, *o2;
+    size_t len;
 
     p = strrchr(binary_filename, '/');
     if (!p) {
@@ -443,11 +593,44 @@ follow_debuglink(char *debuglink, int num_traces, void **traces,
     }
     p[1] = '\0';
 
-    subdir = (char *)alloca(strlen(binary_filename) + 1);
-    strcpy(subdir, binary_filename);
-    strcpy(binary_filename, global_debug_dir);
-    strlcat(binary_filename, subdir, PATH_MAX);
-    strlcat(binary_filename, debuglink, PATH_MAX);
+    len = strlen(binary_filename);
+    if (len >= PATH_MAX - global_debug_dir_len)
+	len = PATH_MAX - global_debug_dir_len - 1;
+    memmove(binary_filename + global_debug_dir_len, binary_filename, len);
+    memcpy(binary_filename, global_debug_dir, global_debug_dir_len);
+    len += global_debug_dir_len;
+    strlcpy(binary_filename + len, debuglink, PATH_MAX - len);
+
+    append_obj(objp);
+    o2 = *objp;
+    o2->base_addr = o1->base_addr;
+    o2->path = o1->path;
+    fill_lines(num_traces, traces, 0, objp, lines, offset);
+}
+
+// check the path pattern of "/usr/lib/debug/.build-id/ab/cdef1234.debug"
+static void
+follow_debuglink_build_id(const char *build_id, size_t build_id_size, int num_traces, void **traces,
+                          obj_info_t **objp, line_info_t *lines, int offset)
+{
+    static const char global_debug_dir[] = "/usr/lib/debug/.build-id/";
+    const size_t global_debug_dir_len = sizeof(global_debug_dir) - 1;
+    char *p;
+    obj_info_t *o1 = *objp, *o2;
+    size_t i;
+
+    if (PATH_MAX < global_debug_dir_len + 1 + build_id_size * 2 + 6) return;
+
+    memcpy(binary_filename, global_debug_dir, global_debug_dir_len);
+    p = binary_filename + global_debug_dir_len;
+    for (i = 0; i < build_id_size; i++) {
+        static const char tbl[] = "0123456789abcdef";
+        unsigned char n = build_id[i];
+        *p++ = tbl[n / 16];
+        *p++ = tbl[n % 16];
+        if (i == 0) *p++ = '/';
+    }
+    strcpy(p, ".debug");
 
     append_obj(objp);
     o2 = *objp;
@@ -455,6 +638,1367 @@ follow_debuglink(char *debuglink, int num_traces, void **traces,
     o2->path = o1->path;
     fill_lines(num_traces, traces, 0, objp, lines, offset);
 }
+#endif
+
+enum
+{
+    DW_TAG_compile_unit = 0x11,
+    DW_TAG_inlined_subroutine = 0x1d,
+    DW_TAG_subprogram = 0x2e,
+};
+
+/* Attributes encodings */
+enum
+{
+    DW_AT_sibling = 0x01,
+    DW_AT_location = 0x02,
+    DW_AT_name = 0x03,
+    /* Reserved 0x04 */
+    /* Reserved 0x05 */
+    /* Reserved 0x06 */
+    /* Reserved 0x07 */
+    /* Reserved 0x08 */
+    DW_AT_ordering = 0x09,
+    /* Reserved 0x0a */
+    DW_AT_byte_size = 0x0b,
+    /* Reserved 0x0c */
+    DW_AT_bit_size = 0x0d,
+    /* Reserved 0x0e */
+    /* Reserved 0x0f */
+    DW_AT_stmt_list = 0x10,
+    DW_AT_low_pc = 0x11,
+    DW_AT_high_pc = 0x12,
+    DW_AT_language = 0x13,
+    /* Reserved 0x14 */
+    DW_AT_discr = 0x15,
+    DW_AT_discr_value = 0x16,
+    DW_AT_visibility = 0x17,
+    DW_AT_import = 0x18,
+    DW_AT_string_length = 0x19,
+    DW_AT_common_reference = 0x1a,
+    DW_AT_comp_dir = 0x1b,
+    DW_AT_const_value = 0x1c,
+    DW_AT_containing_type = 0x1d,
+    DW_AT_default_value = 0x1e,
+    /* Reserved 0x1f */
+    DW_AT_inline = 0x20,
+    DW_AT_is_optional = 0x21,
+    DW_AT_lower_bound = 0x22,
+    /* Reserved 0x23 */
+    /* Reserved 0x24 */
+    DW_AT_producer = 0x25,
+    /* Reserved 0x26 */
+    DW_AT_prototyped = 0x27,
+    /* Reserved 0x28 */
+    /* Reserved 0x29 */
+    DW_AT_return_addr = 0x2a,
+    /* Reserved 0x2b */
+    DW_AT_start_scope = 0x2c,
+    /* Reserved 0x2d */
+    DW_AT_bit_stride = 0x2e,
+    DW_AT_upper_bound = 0x2f,
+    /* Reserved 0x30 */
+    DW_AT_abstract_origin = 0x31,
+    DW_AT_accessibility = 0x32,
+    DW_AT_address_class = 0x33,
+    DW_AT_artificial = 0x34,
+    DW_AT_base_types = 0x35,
+    DW_AT_calling_convention = 0x36,
+    DW_AT_count = 0x37,
+    DW_AT_data_member_location = 0x38,
+    DW_AT_decl_column = 0x39,
+    DW_AT_decl_file = 0x3a,
+    DW_AT_decl_line = 0x3b,
+    DW_AT_declaration = 0x3c,
+    DW_AT_discr_list = 0x3d,
+    DW_AT_encoding = 0x3e,
+    DW_AT_external = 0x3f,
+    DW_AT_frame_base = 0x40,
+    DW_AT_friend = 0x41,
+    DW_AT_identifier_case = 0x42,
+    /* Reserved 0x43 */
+    DW_AT_namelist_item = 0x44,
+    DW_AT_priority = 0x45,
+    DW_AT_segment = 0x46,
+    DW_AT_specification = 0x47,
+    DW_AT_static_link = 0x48,
+    DW_AT_type = 0x49,
+    DW_AT_use_location = 0x4a,
+    DW_AT_variable_parameter = 0x4b,
+    DW_AT_virtuality = 0x4c,
+    DW_AT_vtable_elem_location = 0x4d,
+    DW_AT_allocated = 0x4e,
+    DW_AT_associated = 0x4f,
+    DW_AT_data_location = 0x50,
+    DW_AT_byte_stride = 0x51,
+    DW_AT_entry_pc = 0x52,
+    DW_AT_use_UTF8 = 0x53,
+    DW_AT_extension = 0x54,
+    DW_AT_ranges = 0x55,
+    DW_AT_trampoline = 0x56,
+    DW_AT_call_column = 0x57,
+    DW_AT_call_file = 0x58,
+    DW_AT_call_line = 0x59,
+    DW_AT_description = 0x5a,
+    DW_AT_binary_scale = 0x5b,
+    DW_AT_decimal_scale = 0x5c,
+    DW_AT_small = 0x5d,
+    DW_AT_decimal_sign = 0x5e,
+    DW_AT_digit_count = 0x5f,
+    DW_AT_picture_string = 0x60,
+    DW_AT_mutable = 0x61,
+    DW_AT_threads_scaled = 0x62,
+    DW_AT_explicit = 0x63,
+    DW_AT_object_pointer = 0x64,
+    DW_AT_endianity = 0x65,
+    DW_AT_elemental = 0x66,
+    DW_AT_pure = 0x67,
+    DW_AT_recursive = 0x68,
+    DW_AT_signature = 0x69,
+    DW_AT_main_subprogram = 0x6a,
+    DW_AT_data_bit_offset = 0x6b,
+    DW_AT_const_expr = 0x6c,
+    DW_AT_enum_class = 0x6d,
+    DW_AT_linkage_name = 0x6e,
+    DW_AT_string_length_bit_size = 0x6f,
+    DW_AT_string_length_byte_size = 0x70,
+    DW_AT_rank = 0x71,
+    DW_AT_str_offsets_base = 0x72,
+    DW_AT_addr_base = 0x73,
+    DW_AT_rnglists_base = 0x74,
+    /* Reserved 0x75 */
+    DW_AT_dwo_name = 0x76,
+    DW_AT_reference = 0x77,
+    DW_AT_rvalue_reference = 0x78,
+    DW_AT_macros = 0x79,
+    DW_AT_call_all_calls = 0x7a,
+    DW_AT_call_all_source_calls = 0x7b,
+    DW_AT_call_all_tail_calls = 0x7c,
+    DW_AT_call_return_pc = 0x7d,
+    DW_AT_call_value = 0x7e,
+    DW_AT_call_origin = 0x7f,
+    DW_AT_call_parameter = 0x80,
+    DW_AT_call_pc = 0x81,
+    DW_AT_call_tail_call = 0x82,
+    DW_AT_call_target = 0x83,
+    DW_AT_call_target_clobbered = 0x84,
+    DW_AT_call_data_location = 0x85,
+    DW_AT_call_data_value = 0x86,
+    DW_AT_noreturn = 0x87,
+    DW_AT_alignment = 0x88,
+    DW_AT_export_symbols = 0x89,
+    DW_AT_deleted = 0x8a,
+    DW_AT_defaulted = 0x8b,
+    DW_AT_loclists_base = 0x8c,
+    DW_AT_lo_user = 0x2000,
+    DW_AT_hi_user = 0x3fff
+};
+
+/* Attribute form encodings */
+enum
+{
+    DW_FORM_addr = 0x01,
+    /* Reserved 0x02 */
+    DW_FORM_block2 = 0x03,
+    DW_FORM_block4 = 0x04,
+    DW_FORM_data2 = 0x05,
+    DW_FORM_data4 = 0x06,
+    DW_FORM_data8 = 0x07,
+    DW_FORM_string = 0x08,
+    DW_FORM_block = 0x09,
+    DW_FORM_block1 = 0x0a,
+    DW_FORM_data1 = 0x0b,
+    DW_FORM_flag = 0x0c,
+    DW_FORM_sdata = 0x0d,
+    DW_FORM_strp = 0x0e,
+    DW_FORM_udata = 0x0f,
+    DW_FORM_ref_addr = 0x10,
+    DW_FORM_ref1 = 0x11,
+    DW_FORM_ref2 = 0x12,
+    DW_FORM_ref4 = 0x13,
+    DW_FORM_ref8 = 0x14,
+    DW_FORM_ref_udata = 0x15,
+    DW_FORM_indirect = 0x16,
+    DW_FORM_sec_offset = 0x17,
+    DW_FORM_exprloc = 0x18,
+    DW_FORM_flag_present = 0x19,
+    DW_FORM_strx = 0x1a,
+    DW_FORM_addrx = 0x1b,
+    DW_FORM_ref_sup4 = 0x1c,
+    DW_FORM_strp_sup = 0x1d,
+    DW_FORM_data16 = 0x1e,
+    DW_FORM_line_strp = 0x1f,
+    DW_FORM_ref_sig8 = 0x20,
+    DW_FORM_implicit_const = 0x21,
+    DW_FORM_loclistx = 0x22,
+    DW_FORM_rnglistx = 0x23,
+    DW_FORM_ref_sup8 = 0x24,
+    DW_FORM_strx1 = 0x25,
+    DW_FORM_strx2 = 0x26,
+    DW_FORM_strx3 = 0x27,
+    DW_FORM_strx4 = 0x28,
+    DW_FORM_addrx1 = 0x29,
+    DW_FORM_addrx2 = 0x2a,
+    DW_FORM_addrx3 = 0x2b,
+    DW_FORM_addrx4 = 0x2c
+};
+
+/* Range list entry encodings */
+enum {
+    DW_RLE_end_of_list = 0x00,
+    DW_RLE_base_addressx = 0x01,
+    DW_RLE_startx_endx = 0x02,
+    DW_RLE_startx_length = 0x03,
+    DW_RLE_offset_pair = 0x04,
+    DW_RLE_base_address = 0x05,
+    DW_RLE_start_end = 0x06,
+    DW_RLE_start_length = 0x07
+};
+
+enum {
+    VAL_none = 0,
+    VAL_cstr = 1,
+    VAL_data = 2,
+    VAL_uint = 3,
+    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;
+    const char *cu_end;
+    const char *pend;
+    const char *q0;
+    const char *q;
+    int format; // 4 or 8
+    uint8_t address_size;
+    int level;
+    const char *abbrev_table[ABBREV_TABLE_SIZE];
+} DebugInfoReader;
+
+typedef struct {
+    ptrdiff_t pos;
+    int tag;
+    int has_children;
+} DIE;
+
+typedef struct {
+    union {
+        const char *ptr;
+        uint64_t uint64;
+        int64_t int64;
+        uint64_t addr_idx;
+    } as;
+    uint64_t off;
+    uint64_t at;
+    uint64_t form;
+    size_t size;
+    int type;
+} DebugInfoValue;
+
+#if defined(WORDS_BIGENDIAN)
+#define MERGE_2INTS(a,b,sz) (((uint64_t)(a)<<sz)|(b))
+#else
+#define MERGE_2INTS(a,b,sz) (((uint64_t)(b)<<sz)|(a))
+#endif
+
+static uint16_t
+get_uint16(const uint8_t *p)
+{
+    return (uint16_t)MERGE_2INTS(p[0],p[1],8);
+}
+
+static uint32_t
+get_uint32(const uint8_t *p)
+{
+    return (uint32_t)MERGE_2INTS(get_uint16(p),get_uint16(p+2),16);
+}
+
+static uint64_t
+get_uint64(const uint8_t *p)
+{
+    return MERGE_2INTS(get_uint32(p),get_uint32(p+4),32);
+}
+
+static uint8_t
+read_uint8(const char **ptr)
+{
+    const char *p = *ptr;
+    *ptr = (p + 1);
+    return (uint8_t)*p;
+}
+
+static uint16_t
+read_uint16(const char **ptr)
+{
+    const char *p = *ptr;
+    *ptr = (p + 2);
+    return get_uint16((const uint8_t *)p);
+}
+
+static uint32_t
+read_uint24(const char **ptr)
+{
+    const char *p = *ptr;
+    *ptr = (p + 3);
+    return ((uint8_t)*p << 16) | get_uint16((const uint8_t *)p+1);
+}
+
+static uint32_t
+read_uint32(const char **ptr)
+{
+    const char *p = *ptr;
+    *ptr = (p + 4);
+    return get_uint32((const uint8_t *)p);
+}
+
+static uint64_t
+read_uint64(const char **ptr)
+{
+    const unsigned char *p = (const unsigned char *)*ptr;
+    *ptr = (char *)(p + 8);
+    return get_uint64(p);
+}
+
+static uintptr_t
+read_uintptr(const char **ptr)
+{
+    const unsigned char *p = (const unsigned char *)*ptr;
+    *ptr = (char *)(p + SIZEOF_VOIDP);
+#if SIZEOF_VOIDP == 8
+    return get_uint64(p);
+#else
+    return get_uint32(p);
+#endif
+}
+
+static uint64_t
+read_uint(DebugInfoReader *reader)
+{
+    if (reader->format == 4) {
+        return read_uint32(&reader->p);
+    } else { /* 64 bit */
+        return read_uint64(&reader->p);
+    }
+}
+
+static uint64_t
+read_uleb128(DebugInfoReader *reader)
+{
+    return uleb128(&reader->p);
+}
+
+static int64_t
+read_sleb128(DebugInfoReader *reader)
+{
+    return sleb128(&reader->p);
+}
+
+static void
+debug_info_reader_init(DebugInfoReader *reader, obj_info_t *obj)
+{
+    reader->file = obj->mapped;
+    reader->obj = obj;
+    reader->p = obj->debug_info.ptr;
+    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
+di_skip_die_attributes(const char **p)
+{
+    for (;;) {
+        uint64_t at = uleb128(p);
+        uint64_t form = uleb128(p);
+        if (!at && !form) break;
+        switch (form) {
+          default:
+            break;
+          case DW_FORM_implicit_const:
+            sleb128(p);
+            break;
+        }
+    }
+}
+
+static void
+di_read_debug_abbrev_cu(DebugInfoReader *reader)
+{
+    uint64_t prev = 0;
+    const char *p = reader->q0;
+    for (;;) {
+        uint64_t abbrev_number = uleb128(&p);
+        if (abbrev_number <= prev) break;
+        if (abbrev_number < ABBREV_TABLE_SIZE) {
+            reader->abbrev_table[abbrev_number] = p;
+        }
+        prev = abbrev_number;
+        uleb128(&p); /* tag */
+        p++; /* has_children */
+        di_skip_die_attributes(&p);
+    }
+}
+
+static int
+di_read_debug_line_cu(DebugInfoReader *reader)
+{
+    const char *p;
+    struct LineNumberProgramHeader header;
+
+    p = (const char *)reader->debug_line_cu_end;
+    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;
+
+    return 0;
+}
+
+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;
+    v->type = VAL_uint;
+}
+
+static void
+set_int_value(DebugInfoValue *v, int64_t n)
+{
+    v->as.int64 = n;
+    v->type = VAL_int;
+}
+
+static void
+set_cstr_value(DebugInfoValue *v, const char *s)
+{
+    v->as.ptr = s;
+    v->off = 0;
+    v->type = VAL_cstr;
+}
+
+static void
+set_cstrp_value(DebugInfoValue *v, const char *s, uint64_t off)
+{
+    v->as.ptr = s;
+    v->off = off;
+    v->type = VAL_cstr;
+}
+
+static void
+set_data_value(DebugInfoValue *v, const char *s)
+{
+    v->as.ptr = s;
+    v->type = VAL_data;
+}
+
+static const char *
+get_cstr_value(DebugInfoValue *v)
+{
+    if (v->as.ptr) {
+        return v->as.ptr + v->off;
+    } else {
+        return NULL;
+    }
+}
+
+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:
+        debug_info_reader_read_addr_value(reader, v);
+        break;
+      case DW_FORM_block2:
+        v->size = read_uint16(&reader->p);
+        set_data_value(v, reader->p);
+        reader->p += v->size;
+        break;
+      case DW_FORM_block4:
+        v->size = read_uint32(&reader->p);
+        set_data_value(v, reader->p);
+        reader->p += v->size;
+        break;
+      case DW_FORM_data2:
+        set_uint_value(v, read_uint16(&reader->p));
+        break;
+      case DW_FORM_data4:
+        set_uint_value(v, read_uint32(&reader->p));
+        break;
+      case DW_FORM_data8:
+        set_uint_value(v, read_uint64(&reader->p));
+        break;
+      case DW_FORM_string:
+        v->size = strlen(reader->p);
+        set_cstr_value(v, reader->p);
+        reader->p += v->size + 1;
+        break;
+      case DW_FORM_block:
+        v->size = uleb128(&reader->p);
+        set_data_value(v, reader->p);
+        reader->p += v->size;
+        break;
+      case DW_FORM_block1:
+        v->size = read_uint8(&reader->p);
+        set_data_value(v, reader->p);
+        reader->p += v->size;
+        break;
+      case DW_FORM_data1:
+        set_uint_value(v, read_uint8(&reader->p));
+        break;
+      case DW_FORM_flag:
+        set_uint_value(v, read_uint8(&reader->p));
+        break;
+      case DW_FORM_sdata:
+        set_int_value(v, read_sleb128(reader));
+        break;
+      case DW_FORM_strp:
+        set_cstrp_value(v, reader->obj->debug_str.ptr, read_uint(reader));
+        break;
+      case DW_FORM_udata:
+        set_uint_value(v, read_uleb128(reader));
+        break;
+      case DW_FORM_ref_addr:
+        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 {
+            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:
+        set_uint_value(v, read_uint8(&reader->p));
+        break;
+      case DW_FORM_ref2:
+        set_uint_value(v, read_uint16(&reader->p));
+        break;
+      case DW_FORM_ref4:
+        set_uint_value(v, read_uint32(&reader->p));
+        break;
+      case DW_FORM_ref8:
+        set_uint_value(v, read_uint64(&reader->p));
+        break;
+      case DW_FORM_ref_udata:
+        set_uint_value(v, uleb128(&reader->p));
+        break;
+      case DW_FORM_indirect:
+        /* TODO: read the referred value */
+        set_uint_value(v, uleb128(&reader->p));
+        break;
+      case DW_FORM_sec_offset:
+        set_uint_value(v, read_uint(reader)); /* offset */
+        /* addrptr: debug_addr */
+        /* lineptr: debug_line */
+        /* loclist: debug_loclists */
+        /* loclistptr: debug_loclists */
+        /* macptr: debug_macro */
+        /* rnglist: debug_rnglists */
+        /* rnglistptr: debug_rnglists */
+        /* stroffsetsptr: debug_str_offsets */
+        break;
+      case DW_FORM_exprloc:
+        v->size = (size_t)read_uleb128(reader);
+        set_data_value(v, reader->p);
+        reader->p += v->size;
+        break;
+      case DW_FORM_flag_present:
+        set_uint_value(v, 1);
+        break;
+      case DW_FORM_strx:
+        set_cstr_value(v, resolve_strx(reader, uleb128(&reader->p)));
+        break;
+      case DW_FORM_addrx:
+        set_addr_idx_value(v, uleb128(&reader->p));
+        break;
+      case DW_FORM_ref_sup4:
+        set_uint_value(v, read_uint32(&reader->p));
+        break;
+      case DW_FORM_strp_sup:
+        set_uint_value(v, read_uint(reader));
+        /* *p = reader->sup_file + reader->sup_str->sh_offset + ret; */
+        break;
+      case DW_FORM_data16:
+        v->size = 16;
+        set_data_value(v, reader->p);
+        reader->p += v->size;
+        break;
+      case DW_FORM_line_strp:
+        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));
+        break;
+      case DW_FORM_implicit_const:
+        set_int_value(v, sleb128(&reader->q));
+        break;
+      case DW_FORM_loclistx:
+        set_uint_value(v, read_uleb128(reader));
+        break;
+      case DW_FORM_rnglistx:
+        set_uint_value(v, read_uleb128(reader));
+        break;
+      case DW_FORM_ref_sup8:
+        set_uint_value(v, read_uint64(&reader->p));
+        break;
+      case DW_FORM_strx1:
+        set_cstr_value(v, resolve_strx(reader, read_uint8(&reader->p)));
+        break;
+      case DW_FORM_strx2:
+        set_cstr_value(v, resolve_strx(reader, read_uint16(&reader->p)));
+        break;
+      case DW_FORM_strx3:
+        set_cstr_value(v, resolve_strx(reader, read_uint24(&reader->p)));
+        break;
+      case DW_FORM_strx4:
+        set_cstr_value(v, resolve_strx(reader, read_uint32(&reader->p)));
+        break;
+      case DW_FORM_addrx1:
+        set_addr_idx_value(v, read_uint8(&reader->p));
+        break;
+      case DW_FORM_addrx2:
+        set_addr_idx_value(v, read_uint16(&reader->p));
+        break;
+      case DW_FORM_addrx3:
+        set_addr_idx_value(v, read_uint24(&reader->p));
+        break;
+      case DW_FORM_addrx4:
+        set_addr_idx_value(v, read_uint32(&reader->p));
+        break;
+      case 0:
+        goto fail;
+        break;
+    }
+    return;
+
+  fail:
+    fprintf(stderr, "%d: unsupported form: %#"PRIx64"\n", __LINE__, form);
+    exit(1);
+}
+
+/* find abbrev in current compilation unit */
+static const char *
+di_find_abbrev(DebugInfoReader *reader, uint64_t abbrev_number)
+{
+    const char *p;
+    if (abbrev_number < ABBREV_TABLE_SIZE) {
+        return reader->abbrev_table[abbrev_number];
+    }
+    p = reader->abbrev_table[ABBREV_TABLE_SIZE-1];
+    /* skip 255th record */
+    uleb128(&p); /* tag */
+    p++; /* has_children */
+    di_skip_die_attributes(&p);
+    for (uint64_t n = uleb128(&p); abbrev_number != n; n = uleb128(&p)) {
+        if (n == 0) {
+            fprintf(stderr,"%d: Abbrev Number %"PRId64" not found\n",__LINE__, abbrev_number);
+            exit(1);
+        }
+        uleb128(&p); /* tag */
+        p++; /* has_children */
+        di_skip_die_attributes(&p);
+    }
+    return p;
+}
+
+#if 0
+static void
+hexdump0(const unsigned char *p, size_t n)
+{
+    size_t i;
+    fprintf(stderr, "     0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F\n");
+    for (i=0; i < n; i++){
+        switch (i & 15) {
+          case 0:
+            fprintf(stderr, "%02" PRIdSIZE ": %02X ", i/16, p[i]);
+            break;
+          case 15:
+            fprintf(stderr, "%02X\n", p[i]);
+            break;
+          default:
+            fprintf(stderr, "%02X ", p[i]);
+            break;
+        }
+    }
+    if ((i & 15) != 15) {
+        fprintf(stderr, "\n");
+    }
+}
+#define hexdump(p,n) hexdump0((const unsigned char *)p, n)
+
+static void
+div_inspect(DebugInfoValue *v)
+{
+    switch (v->type) {
+      case VAL_uint:
+        fprintf(stderr,"%d: type:%d size:%" PRIxSIZE " v:%"PRIx64"\n",__LINE__,v->type,v->size,v->as.uint64);
+        break;
+      case VAL_int:
+        fprintf(stderr,"%d: type:%d size:%" PRIxSIZE " v:%"PRId64"\n",__LINE__,v->type,v->size,(int64_t)v->as.uint64);
+        break;
+      case VAL_cstr:
+        fprintf(stderr,"%d: type:%d size:%" PRIxSIZE " v:'%s'\n",__LINE__,v->type,v->size,v->as.ptr);
+        break;
+      case VAL_data:
+        fprintf(stderr,"%d: type:%d size:%" PRIxSIZE " v:\n",__LINE__,v->type,v->size);
+        hexdump(v->as.ptr, 16);
+        break;
+    }
+}
+#endif
+
+static DIE *
+di_read_die(DebugInfoReader *reader, DIE *die)
+{
+    uint64_t abbrev_number = uleb128(&reader->p);
+    if (abbrev_number == 0) {
+        reader->level--;
+        return NULL;
+    }
+
+    reader->q = di_find_abbrev(reader, abbrev_number);
+
+    die->pos = reader->p - reader->obj->debug_info.ptr - 1;
+    die->tag = (int)uleb128(&reader->q); /* tag */
+    die->has_children = *reader->q++; /* has_children */
+    if (die->has_children) {
+        reader->level++;
+    }
+    return die;
+}
+
+static DebugInfoValue *
+di_read_record(DebugInfoReader *reader, DebugInfoValue *vp)
+{
+    uint64_t at = uleb128(&reader->q);
+    uint64_t form = uleb128(&reader->q);
+    if (!at || !form) return NULL;
+    vp->at = at;
+    vp->form = form;
+    debug_info_reader_read_value(reader, form, vp);
+    return vp;
+}
+
+static void
+di_skip_records(DebugInfoReader *reader)
+{
+    for (;;) {
+        DebugInfoValue v = {{}};
+        uint64_t at = uleb128(&reader->q);
+        uint64_t form = uleb128(&reader->q);
+        if (!at || !form) return;
+        debug_info_reader_read_value(reader, form, &v);
+    }
+}
+
+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;
+    uint64_t ranges;
+    bool low_pc_set;
+    bool high_pc_set;
+    bool ranges_set;
+} ranges_t;
+
+static void
+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 = n;
+        ptr->low_pc_set = true;
+        break;
+      case DW_AT_high_pc:
+        if (v->form == DW_FORM_addr) {
+            ptr->high_pc = n;
+        }
+        else {
+            ptr->high_pc = ptr->low_pc + n;
+        }
+        ptr->high_pc_set = true;
+        break;
+      case DW_AT_ranges:
+        ptr->ranges = n;
+        ptr->ranges_set = true;
+        break;
+    }
+}
+
+static uint64_t
+read_dw_form_addr(DebugInfoReader *reader, const char **ptr)
+{
+    const char *p = *ptr;
+    *ptr = p + reader->address_size;
+    if (reader->address_size == 4) {
+        return read_uint32(&p);
+    } else if (reader->address_size == 8) {
+        return read_uint64(&p);
+    } else {
+        fprintf(stderr,"unknown address_size:%d", reader->address_size);
+        abort();
+    }
+}
+
+static uintptr_t
+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) {
+            exit(1);
+        }
+        if (ptr->low_pc <= addr && addr <= ptr->high_pc) {
+            return (uintptr_t)ptr->low_pc;
+        }
+    }
+    else if (ptr->ranges_set) {
+        /* TODO: support base address selection entry */
+        const char *p;
+        uint64_t base = ptr->low_pc_set ? ptr->low_pc : reader->current_low_pc;
+        bool base_valid = true;
+        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;
+                if (rle == DW_RLE_end_of_list) break;
+                switch (rle) {
+                  case DW_RLE_base_addressx:
+                    uleb128(&p);
+                    base_valid = false; /* not supported yet */
+                    break;
+                  case DW_RLE_startx_endx:
+                    uleb128(&p);
+                    uleb128(&p);
+                    break;
+                  case DW_RLE_startx_length:
+                    uleb128(&p);
+                    uleb128(&p);
+                    break;
+                  case DW_RLE_offset_pair:
+                    if (!base_valid) break;
+                    from = (uintptr_t)base + uleb128(&p);
+                    to = (uintptr_t)base + uleb128(&p);
+                    break;
+                  case DW_RLE_base_address:
+                    base = read_dw_form_addr(reader, &p);
+                    base_valid = true;
+                    break;
+                  case DW_RLE_start_end:
+                    from = (uintptr_t)read_dw_form_addr(reader, &p);
+                    to = (uintptr_t)read_dw_form_addr(reader, &p);
+                    break;
+                  case DW_RLE_start_length:
+                    from = (uintptr_t)read_dw_form_addr(reader, &p);
+                    to = from + uleb128(&p);
+                    break;
+                }
+                if (from <= addr && addr < to) {
+                    return from;
+                }
+            }
+            return false;
+        }
+        p = reader->obj->debug_ranges.ptr + ptr->ranges;
+        for (;;) {
+            uintptr_t from = read_uintptr(&p);
+            uintptr_t to = read_uintptr(&p);
+            if (!from && !to) break;
+            if (from == UINTPTR_MAX) {
+                /* base address selection entry */
+                base = to;
+            }
+            else if (base + from <= addr && addr < base + to) {
+                return (uintptr_t)base + from;
+            }
+        }
+    }
+    else if (ptr->low_pc_set) {
+        if (ptr->low_pc == addr) {
+            return (uintptr_t)ptr->low_pc;
+        }
+    }
+    return false;
+}
+
+#if 0
+static void
+ranges_inspect(DebugInfoReader *reader, ranges_t *ptr)
+{
+    if (ptr->high_pc_set) {
+        if (ptr->ranges_set || !ptr->low_pc_set) {
+            fprintf(stderr,"low_pc_set:%d high_pc_set:%d ranges_set:%d\n",ptr->low_pc_set,ptr->high_pc_set,ptr->ranges_set);
+            exit(1);
+        }
+        fprintf(stderr,"low_pc:%"PRIx64" high_pc:%"PRIx64"\n",ptr->low_pc,ptr->high_pc);
+    }
+    else if (ptr->ranges_set) {
+        char *p = reader->obj->debug_ranges.ptr + ptr->ranges;
+        fprintf(stderr,"low_pc:%"PRIx64" ranges:%"PRIx64" %lx ",ptr->low_pc,ptr->ranges, p-reader->obj->mapped);
+        for (;;) {
+            uintptr_t from = read_uintptr(&p);
+            uintptr_t to = read_uintptr(&p);
+            if (!from && !to) break;
+            fprintf(stderr,"%"PRIx64"-%"PRIx64" ",ptr->low_pc+from,ptr->low_pc+to);
+        }
+        fprintf(stderr,"\n");
+    }
+    else if (ptr->low_pc_set) {
+        fprintf(stderr,"low_pc:%"PRIx64"\n",ptr->low_pc);
+    }
+    else {
+        fprintf(stderr,"empty\n");
+    }
+}
+#endif
+
+static int
+di_read_cu(DebugInfoReader *reader)
+{
+    uint64_t unit_length;
+    uint16_t version;
+    uint64_t debug_abbrev_offset;
+    reader->format = 4;
+    reader->current_cu = reader->p;
+    unit_length = read_uint32(&reader->p);
+    if (unit_length == 0xffffffff) {
+        unit_length = read_uint64(&reader->p);
+        reader->format = 8;
+    }
+    reader->cu_end = reader->p + unit_length;
+    version = read_uint16(&reader->p);
+    reader->current_version = version;
+    if (version > 5) {
+        return -1;
+    }
+    else if (version == 5) {
+        /* unit_type = */ read_uint8(&reader->p);
+        reader->address_size = read_uint8(&reader->p);
+        debug_abbrev_offset = read_uint(reader);
+    }
+    else {
+        debug_abbrev_offset = read_uint(reader);
+        reader->address_size = read_uint8(&reader->p);
+    }
+    reader->q0 = reader->obj->debug_abbrev.ptr + debug_abbrev_offset;
+
+    reader->level = 0;
+    di_read_debug_abbrev_cu(reader);
+    if (di_read_debug_line_cu(reader)) return -1;
+
+#if defined(__GNUC__) && !defined(__clang__) && !defined(__INTEL_COMPILER_BUILD_DATE)
+    /* Though DWARF specifies "the applicable base address defaults to the base
+       address of the compilation unit", but GCC seems to use zero as default */
+#else
+    do {
+        DIE die;
+
+        if (!di_read_die(reader, &die)) continue;
+
+        if (die.tag != DW_TAG_compile_unit) {
+            di_skip_records(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:
+                // 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;
+}
+
+static void
+read_abstract_origin(DebugInfoReader *reader, uint64_t form, uint64_t abstract_origin, line_info_t *line)
+{
+    const char *p = reader->p;
+    const char *q = reader->q;
+    int level = reader->level;
+    DIE die;
+
+    switch (form) {
+      case DW_FORM_ref1:
+      case DW_FORM_ref2:
+      case DW_FORM_ref4:
+      case DW_FORM_ref8:
+      case DW_FORM_ref_udata:
+        reader->p = reader->current_cu + abstract_origin;
+        break;
+      case DW_FORM_ref_addr:
+        goto finish; /* not supported yet */
+      case DW_FORM_ref_sig8:
+        goto finish; /* not supported yet */
+      case DW_FORM_ref_sup4:
+      case DW_FORM_ref_sup8:
+        goto finish; /* not supported yet */
+      default:
+        goto finish;
+    }
+    if (!di_read_die(reader, &die)) goto finish;
+
+    /* enumerate abbrev */
+    for (;;) {
+        DebugInfoValue v = {{}};
+        if (!di_read_record(reader, &v)) break;
+        switch (v.at) {
+          case DW_AT_name:
+            line->sname = get_cstr_value(&v);
+            break;
+        }
+    }
+
+  finish:
+    reader->p = p;
+    reader->q = q;
+    reader->level = level;
+}
+
+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 = {};
+        line_info_t line = {};
+
+        if (!di_read_die(reader, &die)) continue;
+        /* fprintf(stderr,"%d:%tx: <%d>\n",__LINE__,die.pos,reader->level,die.tag); */
+
+        if (die.tag != DW_TAG_subprogram && die.tag != DW_TAG_inlined_subroutine) {
+          skip_die:
+            di_skip_records(reader);
+            continue;
+        }
+
+        /* enumerate abbrev */
+        for (;;) {
+            DebugInfoValue v = {{}};
+            /* ptrdiff_t pos = reader->p - reader->p0; */
+            if (!di_read_record(reader, &v)) break;
+            /* fprintf(stderr,"\n%d:%tx: AT:%lx FORM:%lx\n",__LINE__,pos,v.at,v.form); */
+            /* div_inspect(&v); */
+            switch (v.at) {
+              case DW_AT_name:
+                line.sname = get_cstr_value(&v);
+                break;
+              case DW_AT_call_file:
+                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;
+                break;
+              case DW_AT_low_pc:
+              case DW_AT_high_pc:
+              case DW_AT_ranges:
+                ranges_set(&ranges, &v, &addr_header, reader->current_addr_base);
+                break;
+              case DW_AT_declaration:
+                goto skip_die;
+              case DW_AT_inline:
+                /* 1 or 3 */
+                break; /* goto skip_die; */
+              case DW_AT_abstract_origin:
+                read_abstract_origin(reader, v.form, v.as.uint64, &line);
+                break; /* goto skip_die; */
+            }
+        }
+        /* ranges_inspect(reader, &ranges); */
+        /* fprintf(stderr,"%d:%tx: %x ",__LINE__,diepos,die.tag); */
+        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, &rnglists_header);
+            if (saddr) {
+                /* 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));
+                    lines[i].next = lp;
+                    lp->dirname = line.dirname;
+                    lp->filename = line.filename;
+                    lp->line = line.line;
+                    lp->saddr = 0;
+                }
+                lines[i].path = reader->obj->path;
+                lines[i].base_addr = line.base_addr;
+                lines[i].sname = line.sname;
+                lines[i].saddr = saddr + reader->obj->base_addr - reader->obj->vmaddr;
+            }
+        }
+    }
+}
+
+// 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)
+{
+    *ptr = NULL;
+#ifdef SUPPORT_COMPRESSED_DEBUG_LINE
+    ElfW(Chdr) *chdr = (ElfW(Chdr) *)(file + shdr->sh_offset);
+    unsigned long destsize = chdr->ch_size;
+    int ret = 0;
+
+    if (chdr->ch_type != ELFCOMPRESS_ZLIB) {
+	/* unsupported compression type */
+	return 0;
+    }
+
+    *ptr = malloc(destsize);
+    if (!*ptr) return 0;
+    ret = uncompress((Bytef *)*ptr, &destsize,
+	    (const Bytef*)chdr + sizeof(ElfW(Chdr)),
+            shdr->sh_size - sizeof(ElfW(Chdr)));
+    if (ret != Z_OK) goto fail;
+    return destsize;
+
+fail:
+    free(*ptr);
+    *ptr = NULL;
+#endif
+    return 0;
+}
 
 /* read file and fill lines */
 static uintptr_t
@@ -463,10 +2007,10 @@ fill_lines(int num_traces, void **traces, int check_debuglink,
 {
     int i, j;
     char *shstr;
-    char *section_name;
     ElfW(Ehdr) *ehdr;
     ElfW(Shdr) *shdr, *shstr_shdr;
-    ElfW(Shdr) *debug_line_shdr = NULL, *gnu_debuglink_shdr = NULL;
+    ElfW(Shdr) *gnu_debuglink_shdr = NULL;
+    ElfW(Shdr) *note_gnu_build_id = NULL;
     int fd;
     off_t filesize;
     char *file;
@@ -502,6 +2046,7 @@ fill_lines(int num_traces, void **traces, int check_debuglink,
 	kprintf("mmap: %s\n", strerror(e));
 	goto fail;
     }
+    close(fd);
 
     ehdr = (ElfW(Ehdr) *)file;
     if (memcmp(ehdr->e_ident, "\177ELF", 4) != 0) {
@@ -509,11 +2054,8 @@ fill_lines(int num_traces, void **traces, int check_debuglink,
 	 * Huh? Maybe filename was overridden by setproctitle() and
 	 * it match non-elf file.
 	 */
-	close(fd);
 	goto fail;
     }
-
-    obj->fd = fd;
     obj->mapped = file;
     obj->mapped_size = (size_t)filesize;
 
@@ -523,7 +2065,7 @@ fill_lines(int num_traces, void **traces, int check_debuglink,
     shstr = file + shstr_shdr->sh_offset;
 
     for (i = 0; i < ehdr->e_shnum; i++) {
-	section_name = shstr + shdr[i].sh_name;
+        char *section_name = shstr + shdr[i].sh_name;
 	switch (shdr[i].sh_type) {
 	  case SHT_STRTAB:
 	    if (!strcmp(section_name, ".strtab")) {
@@ -541,13 +2083,44 @@ fill_lines(int num_traces, void **traces, int check_debuglink,
 	    /* if (!strcmp(section_name, ".dynsym")) */
 	    dynsym_shdr = shdr + i;
 	    break;
+          case SHT_NOTE:
+            if (!strcmp(section_name, ".note.gnu.build-id")) {
+                note_gnu_build_id = shdr + i;
+            }
+            break;
 	  case SHT_PROGBITS:
-	    if (!strcmp(section_name, ".debug_line")) {
-		debug_line_shdr = shdr + i;
-	    }
-	    else if (!strcmp(section_name, ".gnu_debuglink")) {
+	    if (!strcmp(section_name, ".gnu_debuglink")) {
 		gnu_debuglink_shdr = shdr + i;
 	    }
+            else {
+                const char *debug_section_names[] = {
+                    ".debug_abbrev",
+                    ".debug_info",
+                    ".debug_line",
+                    ".debug_ranges",
+                    ".debug_str_offsets",
+                    ".debug_addr",
+                    ".debug_rnglists",
+                    ".debug_str",
+                    ".debug_line_str"
+                };
+
+                for (j=0; j < DWARF_SECTION_COUNT; j++) {
+                    struct dwarf_section *s = obj_dwarf_section_at(obj, j);
+
+                    if (strcmp(section_name, debug_section_names[j]) != 0)
+                        continue;
+
+                    s->ptr = file + shdr[i].sh_offset;
+                    s->size = shdr[i].sh_size;
+                    s->flags = shdr[i].sh_flags;
+                    if (s->flags & SHF_COMPRESSED) {
+                        s->size = uncompress_debug_section(&shdr[i], file, &s->ptr);
+                        if (!s->size) goto fail;
+                    }
+                    break;
+                }
+            }
 	    break;
 	}
     }
@@ -559,20 +2132,22 @@ fill_lines(int num_traces, void **traces, int check_debuglink,
 	    char *strtab = file + dynstr_shdr->sh_offset;
 	    ElfW(Sym) *symtab = (ElfW(Sym) *)(file + dynsym_shdr->sh_offset);
 	    int symtab_count = (int)(dynsym_shdr->sh_size / sizeof(ElfW(Sym)));
-	    for (j = 0; j < symtab_count; j++) {
-		ElfW(Sym) *sym = &symtab[j];
-		Dl_info info;
-		void *h, *s;
-		if (ELF_ST_TYPE(sym->st_info) != STT_FUNC || sym->st_size <= 0) continue;
-		h = dlopen(NULL, RTLD_NOW|RTLD_LOCAL);
-		if (!h) continue;
-		s = dlsym(h, strtab + sym->st_name);
-		if (!s) continue;
-		if (dladdr(s, &info)) {
-		    dladdr_fbase = (uintptr_t)info.dli_fbase;
-		    break;
-		}
-	    }
+            void *handle = dlopen(NULL, RTLD_NOW|RTLD_LOCAL);
+            if (handle) {
+                for (j = 0; j < symtab_count; j++) {
+                    ElfW(Sym) *sym = &symtab[j];
+                    Dl_info info;
+                    void *s;
+                    if (ELF_ST_TYPE(sym->st_info) != STT_FUNC || sym->st_size == 0) continue;
+                    s = dlsym(handle, strtab + sym->st_name);
+                    if (s && dladdr(s, &info)) {
+                        obj->base_addr = dladdr_fbase;
+                        dladdr_fbase = (uintptr_t)info.dli_fbase;
+                        break;
+                    }
+                }
+                dlclose(handle);
+            }
 	    if (ehdr->e_type == ET_EXEC) {
 		obj->base_addr = 0;
 	    }
@@ -583,33 +2158,48 @@ fill_lines(int num_traces, void **traces, int check_debuglink,
 	}
     }
 
-    if (!symtab_shdr) {
-	symtab_shdr = dynsym_shdr;
-	strtab_shdr = dynstr_shdr;
-    }
-
-    if (symtab_shdr && strtab_shdr) {
-	char *strtab = file + strtab_shdr->sh_offset;
-	ElfW(Sym) *symtab = (ElfW(Sym) *)(file + symtab_shdr->sh_offset);
-	int symtab_count = (int)(symtab_shdr->sh_size / sizeof(ElfW(Sym)));
-	for (j = 0; j < symtab_count; j++) {
-	    ElfW(Sym) *sym = &symtab[j];
-	    uintptr_t saddr = (uintptr_t)sym->st_value + obj->base_addr;
-	    if (ELF_ST_TYPE(sym->st_info) != STT_FUNC || sym->st_size <= 0) continue;
-	    for (i = offset; i < num_traces; i++) {
-		uintptr_t d = (uintptr_t)traces[i] - saddr;
-		if (lines[i].line > 0 || d <= 0 || d > (uintptr_t)sym->st_size)
-		    continue;
-		/* fill symbol name and addr from .symtab */
-		lines[i].sname = strtab + sym->st_name;
-		lines[i].saddr = saddr;
-		lines[i].path  = obj->path;
-		lines[i].base_addr = obj->base_addr;
-	    }
-	}
+    if (obj->debug_info.ptr && obj->debug_abbrev.ptr) {
+        DebugInfoReader reader;
+        debug_info_reader_init(&reader, obj);
+        i = 0;
+        while (reader.p < reader.pend) {
+            /* fprintf(stderr, "%d:%tx: CU[%d]\n", __LINE__, reader.p - reader.obj->debug_info.ptr, i++); */
+            if (di_read_cu(&reader)) goto use_symtab;
+            debug_info_read(&reader, num_traces, traces, lines, offset);
+        }
+    }
+    else {
+        /* This file doesn't have dwarf, use symtab or dynsym */
+use_symtab:
+        if (!symtab_shdr) {
+            /* This file doesn't have symtab, use dynsym instead */
+            symtab_shdr = dynsym_shdr;
+            strtab_shdr = dynstr_shdr;
+        }
+
+        if (symtab_shdr && strtab_shdr) {
+            char *strtab = file + strtab_shdr->sh_offset;
+            ElfW(Sym) *symtab = (ElfW(Sym) *)(file + symtab_shdr->sh_offset);
+            int symtab_count = (int)(symtab_shdr->sh_size / sizeof(ElfW(Sym)));
+            for (j = 0; j < symtab_count; j++) {
+                ElfW(Sym) *sym = &symtab[j];
+                uintptr_t saddr = (uintptr_t)sym->st_value + obj->base_addr;
+                if (ELF_ST_TYPE(sym->st_info) != STT_FUNC) continue;
+                for (i = offset; i < num_traces; i++) {
+                    uintptr_t d = (uintptr_t)traces[i] - saddr;
+                    if (lines[i].line > 0 || d > (uintptr_t)sym->st_size)
+                        continue;
+                    /* fill symbol name and addr from .symtab */
+                    if (!lines[i].sname) lines[i].sname = strtab + sym->st_name;
+                    lines[i].saddr = saddr;
+                    lines[i].path  = obj->path;
+                    lines[i].base_addr = obj->base_addr;
+                }
+            }
+        }
     }
 
-    if (!debug_line_shdr) {
+    if (!obj->debug_line.ptr) {
 	/* This file doesn't have .debug_line section,
 	   let's check .gnu_debuglink section instead. */
 	if (gnu_debuglink_shdr && check_debuglink) {
@@ -617,21 +2207,251 @@ fill_lines(int num_traces, void **traces, int check_debuglink,
 			     num_traces, traces,
 			     objp, lines, offset);
 	}
+        if (note_gnu_build_id && check_debuglink) {
+            ElfW(Nhdr) *nhdr = (ElfW(Nhdr)*) (file + note_gnu_build_id->sh_offset);
+            const char *build_id = (char *)(nhdr + 1) + nhdr->n_namesz;
+            follow_debuglink_build_id(build_id, nhdr->n_descsz,
+			       num_traces, traces,
+			       objp, lines, offset);
+        }
 	goto finish;
     }
 
-    parse_debug_line(num_traces, traces,
-		     file + debug_line_shdr->sh_offset,
-		     debug_line_shdr->sh_size,
-		     obj, lines, offset);
+    if (parse_debug_line(num_traces, traces,
+            obj->debug_line.ptr,
+            obj->debug_line.size,
+            obj, lines, offset) == -1)
+        goto fail;
+
 finish:
     return dladdr_fbase;
 fail:
     return (uintptr_t)-1;
 }
+#else /* Mach-O */
+/* read file and fill lines */
+static uintptr_t
+fill_lines(int num_traces, void **traces, int check_debuglink,
+        obj_info_t **objp, line_info_t *lines, int offset)
+{
+# ifdef __LP64__
+#  define LP(x) x##_64
+# else
+#  define LP(x) x
+# endif
+    int fd;
+    off_t filesize;
+    char *file, *p = NULL;
+    obj_info_t *obj = *objp;
+    struct LP(mach_header) *header;
+    uintptr_t dladdr_fbase = 0;
+
+    {
+        char *s = binary_filename;
+        char *base = strrchr(binary_filename, '/')+1;
+        size_t max = PATH_MAX;
+        size_t size = strlen(binary_filename);
+        size_t basesize = size - (base - binary_filename);
+        s += size;
+        max -= size;
+        p = s;
+        size = strlcpy(s, ".dSYM/Contents/Resources/DWARF/", max);
+        if (size == 0) goto fail;
+        s += size;
+        max -= size;
+        if (max <= basesize) goto fail;
+        memcpy(s, base, basesize);
+        s[basesize] = 0;
+
+        fd = open(binary_filename, O_RDONLY);
+        if (fd < 0) {
+            *p = 0; /* binary_filename becomes original file name */
+            fd = open(binary_filename, O_RDONLY);
+            if (fd < 0) {
+                goto fail;
+            }
+        }
+    }
+
+    filesize = lseek(fd, 0, SEEK_END);
+    if (filesize < 0) {
+        int e = errno;
+        close(fd);
+        kprintf("lseek: %s\n", strerror(e));
+        goto fail;
+    }
+#if SIZEOF_OFF_T > SIZEOF_SIZE_T
+    if (filesize > (off_t)SIZE_MAX) {
+        close(fd);
+        kprintf("Too large file %s\n", binary_filename);
+        goto fail;
+    }
+#endif
+    lseek(fd, 0, SEEK_SET);
+    /* async-signal unsafe */
+    file = (char *)mmap(NULL, (size_t)filesize, PROT_READ, MAP_SHARED, fd, 0);
+    if (file == MAP_FAILED) {
+        int e = errno;
+        close(fd);
+        kprintf("mmap: %s\n", strerror(e));
+        goto fail;
+    }
+    close(fd);
+
+    obj->mapped = file;
+    obj->mapped_size = (size_t)filesize;
+
+    header = (struct LP(mach_header) *)file;
+    if (header->magic == LP(MH_MAGIC)) {
+        /* non universal binary */
+        p = file;
+    }
+    else if (header->magic == FAT_CIGAM) {
+        struct LP(mach_header) *mhp = _NSGetMachExecuteHeader();
+        struct fat_header *fat = (struct fat_header *)file;
+        char *q = file + sizeof(*fat);
+        uint32_t nfat_arch = __builtin_bswap32(fat->nfat_arch);
+        /* fprintf(stderr,"%d: fat:%s %d\n",__LINE__, binary_filename,nfat_arch); */
+        for (uint32_t i = 0; i < nfat_arch; i++) {
+            struct fat_arch *arch = (struct fat_arch *)q;
+            cpu_type_t cputype = __builtin_bswap32(arch->cputype);
+            cpu_subtype_t cpusubtype = __builtin_bswap32(arch->cpusubtype);
+            uint32_t offset = __builtin_bswap32(arch->offset);
+            /* fprintf(stderr,"%d: fat %d %x/%x %x/%x\n",__LINE__, i, mhp->cputype,mhp->cpusubtype, cputype,cpusubtype); */
+            if (mhp->cputype == cputype &&
+                    (cpu_subtype_t)(mhp->cpusubtype & ~CPU_SUBTYPE_MASK) == cpusubtype) {
+                p = file + offset;
+                file = p;
+                header = (struct LP(mach_header) *)p;
+                if (header->magic == LP(MH_MAGIC)) {
+                    goto found_mach_header;
+                }
+                break;
+            }
+            q += sizeof(*arch);
+        }
+        kprintf("'%s' is not a Mach-O universal binary file!\n",binary_filename);
+        close(fd);
+        goto fail;
+    }
+    else {
+        kprintf("'%s' is not a "
+# ifdef __LP64__
+                "64"
+# else
+                "32"
+# endif
+                "-bit Mach-O file!\n",binary_filename);
+        close(fd);
+        goto fail;
+    }
+found_mach_header:
+    p += sizeof(*header);
+
+    for (uint32_t i = 0; i < (uint32_t)header->ncmds; i++) {
+        struct load_command *lcmd = (struct load_command *)p;
+        switch (lcmd->cmd) {
+          case LP(LC_SEGMENT):
+            {
+                static const char *debug_section_names[] = {
+                    "__debug_abbrev",
+                    "__debug_info",
+                    "__debug_line",
+                    "__debug_ranges",
+                    "__debug_str_offsets",
+                    "__debug_addr",
+                    "__debug_rnglists",
+                    "__debug_str",
+                    "__debug_line_str",
+                };
+                struct LP(segment_command) *scmd = (struct LP(segment_command) *)lcmd;
+                if (strcmp(scmd->segname, "__TEXT") == 0) {
+                    obj->vmaddr = scmd->vmaddr;
+                }
+                else if (strcmp(scmd->segname, "__DWARF") == 0) {
+                    p += sizeof(struct LP(segment_command));
+                    for (uint64_t i = 0; i < scmd->nsects; i++) {
+                        struct LP(section) *sect = (struct LP(section) *)p;
+                        p += sizeof(struct LP(section));
+                        for (int j=0; j < DWARF_SECTION_COUNT; j++) {
+                            struct dwarf_section *s = obj_dwarf_section_at(obj, j);
+
+                            if (strcmp(sect->sectname, debug_section_names[j]) != 0)
+                                continue;
+
+                            s->ptr = file + sect->offset;
+                            s->size = sect->size;
+                            s->flags = sect->flags;
+                            if (s->flags & SHF_COMPRESSED) {
+                                goto fail;
+                            }
+                            break;
+                        }
+                    }
+                }
+            }
+            break;
+
+          case LC_SYMTAB:
+            {
+                struct symtab_command *cmd = (struct symtab_command *)lcmd;
+                struct LP(nlist) *nl = (struct LP(nlist) *)(file + cmd->symoff);
+                char *strtab = file + cmd->stroff, *sname = 0;
+                uint32_t j;
+                uintptr_t saddr = 0;
+                /* kprintf("[%2d]: %x/symtab %p\n", i, cmd->cmd, (void *)p); */
+                for (j = 0; j < cmd->nsyms; j++) {
+                    uintptr_t symsize, d;
+                    struct LP(nlist) *e = &nl[j];
+                        /* kprintf("[%2d][%4d]: %02x/%x/%x: %s %llx\n", i, j, e->n_type,e->n_sect,e->n_desc,strtab+e->n_un.n_strx,e->n_value); */
+                    if (e->n_type != N_FUN) continue;
+                    if (e->n_sect) {
+                        saddr = (uintptr_t)e->n_value + obj->base_addr - obj->vmaddr;
+                        sname = strtab + e->n_un.n_strx;
+                        /* kprintf("[%2d][%4d]: %02x/%x/%x: %s %llx\n", i, j, e->n_type,e->n_sect,e->n_desc,strtab+e->n_un.n_strx,e->n_value); */
+                        continue;
+                    }
+                    for (int k = offset; k < num_traces; k++) {
+                        d = (uintptr_t)traces[k] - saddr;
+                        symsize = e->n_value;
+                        /* kprintf("%lx %lx %lx\n",saddr,symsize,traces[k]); */
+                        if (lines[k].line > 0 || d > (uintptr_t)symsize)
+                            continue;
+                        /* fill symbol name and addr from .symtab */
+                        if (!lines[k].sname) lines[k].sname = sname;
+                        lines[k].saddr = saddr;
+                        lines[k].path  = obj->path;
+                        lines[k].base_addr = obj->base_addr;
+                    }
+                }
+            }
+        }
+        p += lcmd->cmdsize;
+    }
+
+    if (obj->debug_info.ptr && obj->debug_abbrev.ptr) {
+        DebugInfoReader reader;
+        debug_info_reader_init(&reader, obj);
+        while (reader.p < reader.pend) {
+            if (di_read_cu(&reader)) goto fail;
+            debug_info_read(&reader, num_traces, traces, lines, offset);
+        }
+    }
+
+    if (parse_debug_line(num_traces, traces,
+            obj->debug_line.ptr,
+            obj->debug_line.size,
+            obj, lines, offset) == -1)
+        goto fail;
+
+    return dladdr_fbase;
+fail:
+    return (uintptr_t)-1;
+}
+#endif
 
 #define HAVE_MAIN_EXE_PATH
-#if defined(__FreeBSD__)
+#if defined(__FreeBSD__) || defined(__DragonFly__)
 # include <sys/sysctl.h>
 #endif
 /* ssize_t main_exe_path(void)
@@ -640,17 +2460,22 @@ fail:
  * and returns strlen(binary_filename).
  * it is NUL terminated.
  */
-#if defined(__linux__)
-ssize_t
+#if defined(__linux__) || defined(__NetBSD__)
+static ssize_t
 main_exe_path(void)
 {
-# define PROC_SELF_EXE "/proc/self/exe"
+# if defined(__linux__)
+#  define PROC_SELF_EXE "/proc/self/exe"
+# elif defined(__NetBSD__)
+#  define PROC_SELF_EXE "/proc/curproc/exe"
+# endif
     ssize_t len = readlink(PROC_SELF_EXE, binary_filename, PATH_MAX);
+    if (len < 0) return 0;
     binary_filename[len] = 0;
     return len;
 }
-#elif defined(__FreeBSD__)
-ssize_t
+#elif defined(__FreeBSD__) || defined(__DragonFly__)
+static ssize_t
 main_exe_path(void)
 {
     int mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1};
@@ -663,10 +2488,69 @@ main_exe_path(void)
     len--; /* sysctl sets strlen+1 */
     return len;
 }
+#elif defined(HAVE_LIBPROC_H)
+static ssize_t
+main_exe_path(void)
+{
+    int len = proc_pidpath(getpid(), binary_filename, PATH_MAX);
+    if (len == 0) return 0;
+    binary_filename[len] = 0;
+    return len;
+}
 #else
 #undef HAVE_MAIN_EXE_PATH
 #endif
 
+static void
+print_line0(line_info_t *line, void *address)
+{
+    uintptr_t addr = (uintptr_t)address;
+    uintptr_t d = addr - line->saddr;
+    if (!address) {
+        /* inlined */
+        if (line->dirname && line->dirname[0]) {
+            kprintf("%s(%s) %s/%s:%d\n", line->path, line->sname, line->dirname, line->filename, line->line);
+        }
+        else {
+            kprintf("%s(%s) %s:%d\n", line->path, line->sname, line->filename, line->line);
+        }
+    }
+    else if (!line->path) {
+        kprintf("[0x%"PRIxPTR"]\n", addr);
+    }
+    else if (!line->sname) {
+        kprintf("%s(0x%"PRIxPTR") [0x%"PRIxPTR"]\n", line->path, addr-line->base_addr, addr);
+    }
+    else if (!line->saddr) {
+        kprintf("%s(%s) [0x%"PRIxPTR"]\n", line->path, line->sname, addr);
+    }
+    else if (line->line <= 0) {
+        kprintf("%s(%s+0x%"PRIxPTR") [0x%"PRIxPTR"]\n", line->path, line->sname,
+                d, addr);
+    }
+    else if (!line->filename) {
+        kprintf("%s(%s+0x%"PRIxPTR") [0x%"PRIxPTR"] ???:%d\n", line->path, line->sname,
+                d, addr, line->line);
+    }
+    else if (line->dirname && line->dirname[0]) {
+        kprintf("%s(%s+0x%"PRIxPTR") [0x%"PRIxPTR"] %s/%s:%d\n", line->path, line->sname,
+                d, addr, line->dirname, line->filename, line->line);
+    }
+    else {
+        kprintf("%s(%s+0x%"PRIxPTR") [0x%"PRIxPTR"] %s:%d\n", line->path, line->sname,
+                d, addr, line->filename, line->line);
+    }
+}
+
+static void
+print_line(line_info_t *line, void *address)
+{
+    print_line0(line, address);
+    if (line->next) {
+        print_line(line->next, NULL);
+    }
+}
+
 void
 rb_dump_backtrace_with_lines(int num_traces, void **traces)
 {
@@ -676,6 +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;
@@ -706,8 +2591,8 @@ rb_dump_backtrace_with_lines(int num_traces, void **traces)
 	    /* if the binary is strip-ed, this may effect */
 	    for (p=dladdr_fbases; *p; p++) {
 		if (*p == info.dli_fbase) {
-		    lines[i].path = info.dli_fname;
-		    lines[i].sname = info.dli_sname;
+		    if (info.dli_fname) lines[i].path = info.dli_fname;
+		    if (info.dli_sname) lines[i].sname = info.dli_sname;
 		    goto next_line;
 		}
 	    }
@@ -717,9 +2602,14 @@ rb_dump_backtrace_with_lines(int num_traces, void **traces)
 	    obj->base_addr = (uintptr_t)info.dli_fbase;
 	    path = info.dli_fname;
 	    obj->path = path;
-	    lines[i].path = path;
-	    strcpy(binary_filename, path);
-	    fill_lines(num_traces, traces, 1, &obj, lines, i);
+	    if (path) lines[i].path = path;
+            if (info.dli_sname) {
+                lines[i].sname = info.dli_sname;
+                lines[i].saddr = (uintptr_t)info.dli_saddr;
+            }
+	    strlcpy(binary_filename, path, PATH_MAX);
+	    if (fill_lines(num_traces, traces, 1, &obj, lines, i) == (uintptr_t)-1)
+		break;
 	}
 next_line:
 	continue;
@@ -727,46 +2617,36 @@ next_line:
 
     /* output */
     for (i = 0; i < num_traces; i++) {
-	line_info_t *line = &lines[i];
-	uintptr_t addr = (uintptr_t)traces[i];
-	uintptr_t d = addr - line->saddr;
-	if (!line->path) {
-	    kprintf("[0x%lx]\n", addr);
-	}
-	else if (!line->saddr || !line->sname) {
-	    kprintf("%s [0x%lx]\n", line->path, addr);
-	}
-	else if (line->line <= 0) {
-	    kprintf("%s(%s+0x%lx) [0x%lx]\n", line->path, line->sname,
-		    d, addr);
-	}
-	else if (!line->filename) {
-	    kprintf("%s(%s+0x%lx) [0x%lx] ???:%d\n", line->path, line->sname,
-		    d, addr, line->line);
-	}
-	else if (line->dirname && line->dirname[0]) {
-	    kprintf("%s(%s+0x%lx) [0x%lx] %s/%s:%d\n", line->path, line->sname,
-		    d, addr, line->dirname, line->filename, line->line);
-	}
-	else {
-	    kprintf("%s(%s+0x%lx) [0x%lx] %s:%d\n", line->path, line->sname,
-		    d, addr, line->filename, line->line);
-	}
+        print_line(&lines[i], traces[i]);
+
 	/* FreeBSD's backtrace may show _start and so on */
-	if (line->sname && strcmp("main", line->sname) == 0)
+	if (lines[i].sname && strcmp("main", lines[i].sname) == 0)
 	    break;
     }
 
     /* free */
     while (obj) {
 	obj_info_t *o = obj;
-	obj = o->next;
-	if (o->fd) {
-	    munmap(o->mapped, o->mapped_size);
-	    close(o->fd);
+        for (i=0; i < DWARF_SECTION_COUNT; i++) {
+            struct dwarf_section *s = obj_dwarf_section_at(obj, i);
+            if (s->flags & SHF_COMPRESSED) {
+                free(s->ptr);
+            }
+        }
+	if (obj->mapped_size) {
+	    munmap(obj->mapped, obj->mapped_size);
 	}
+	obj = o->next;
 	free(o);
     }
+    for (i = 0; i < num_traces; i++) {
+        line_info_t *line = lines[i].next;
+        while (line) {
+            line_info_t *l = line;
+            line = line->next;
+            free(l);
+        }
+    }
     free(lines);
     free(dladdr_fbases);
 }
@@ -812,7 +2692,7 @@ next_line:
 #define MAXNBUF (sizeof(intmax_t) * CHAR_BIT + 1)
 static inline int toupper(int c) { return ('A' <= c && c <= 'Z') ? (c&0x5f) : c; }
 #define    hex2ascii(hex)  (hex2ascii_data[hex])
-char const hex2ascii_data[] = "0123456789abcdefghijklmnopqrstuvwxyz";
+static const char hex2ascii_data[] = "0123456789abcdefghijklmnopqrstuvwxyz";
 static inline int imax(int a, int b) { return (a > b ? a : b); }
 static int kvprintf(char const *fmt, void (*func)(int), void *arg, int radix, va_list ap);
 
@@ -826,7 +2706,7 @@ static void putce(int c)
     (void)ret;
 }
 
-int
+static int
 kprintf(const char *fmt, ...)
 {
 	va_list ap;
diff --git a/addr2line.h b/addr2line.h
index d99f010934..f09b665800 100644
--- a/addr2line.h
+++ b/addr2line.h
@@ -1,3 +1,5 @@
+#ifndef RUBY_ADDR2LINE_H
+#define RUBY_ADDR2LINE_H
 /**********************************************************************
 
   addr2line.h -
@@ -8,10 +10,7 @@
 
 **********************************************************************/
 
-#ifndef RUBY_ADDR2LINE_H
-#define RUBY_ADDR2LINE_H
-
-#ifdef USE_ELF
+#if (defined(USE_ELF) || defined(HAVE_MACH_O_LOADER_H))
 
 void
 rb_dump_backtrace_with_lines(int num_traces, void **traces);
diff --git a/appveyor.yml b/appveyor.yml
deleted file mode 100644
index e08314003d..0000000000
--- a/appveyor.yml
+++ /dev/null
@@ -1,37 +0,0 @@
----
-shallow_clone: true
-platform: x64
-install:
-  - SET
-  - '"C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\vcvarsall.bat" amd64'
-  - SET PATH=\usr\local\bin;C:\Ruby22-x64\bin;C:\Ruby21-x64\Devkit\mingw\bin;%PATH%;C:\msys64\usr\bin
-  - ruby --version
-  - 'cl'
-  - SET
-  - mkdir \usr\local\bin
-  - mkdir \usr\local\include
-  - mkdir \usr\local\lib
-  - ps: Start-FileDownload 'http://ftp.openbsd.org/pub/OpenBSD/LibreSSL/libressl-2.3.5-windows.zip'
-  - 7z x libressl-2.3.5-windows.zip
-  - copy libressl-2.3.5-windows\x64\libcrypto-37.lib \usr\local\lib\crypto.lib
-  - copy libressl-2.3.5-windows\x64\libssl-38.lib    \usr\local\lib\ssl.lib
-  - copy libressl-2.3.5-windows\x64\libcrypto-37.dll \usr\local\bin
-  - copy libressl-2.3.5-windows\x64\libssl-38.dll    \usr\local\bin
-  - xcopy /e libressl-2.3.5-windows\include          \usr\local\include
-  - ps: Start-FileDownload 'http://zlib.net/zlib128.zip'
-  - 7z x zlib128.zip
-  - cd zlib-1.2.8
-  - nmake -f win32/Makefile.msc
-  - copy zlib1.dll \usr\local\bin
-  - copy zlib.lib  \usr\local\lib
-  - copy zconf.h   \usr\local\include
-  - copy zlib.h    \usr\local\include
-build_script:
-  - cd %APPVEYOR_BUILD_FOLDER%
-  - win32\configure.bat --without-ext=+,dbm,gdbm,readline,tk* --with-opt-dir=/usr/local
-  - nmake -l up
-  - nmake -l
-  - nmake install-nodoc
-test_script:
-  - nmake -l "OPTS=-v -q" btest
-  - nmake -l "OPTS=-v -q" test-basic
diff --git a/array.c b/array.c
index 6f1d65a88e..b76e9a64a3 100644
--- a/array.c
+++ b/array.c
@@ -11,51 +11,107 @@
 
 **********************************************************************/
 
+#include "debug_counter.h"
+#include "id.h"
 #include "internal.h"
-#include "ruby/util.h"
-#include "ruby/st.h"
+#include "internal/array.h"
+#include "internal/compar.h"
+#include "internal/enum.h"
+#include "internal/gc.h"
+#include "internal/hash.h"
+#include "internal/numeric.h"
+#include "internal/object.h"
+#include "internal/proc.h"
+#include "internal/rational.h"
+#include "internal/vm.h"
 #include "probes.h"
-#include "id.h"
+#include "ruby/encoding.h"
+#include "ruby/st.h"
+#include "ruby/util.h"
+#include "transient_heap.h"
+#include "builtin.h"
 
-#ifndef ARRAY_DEBUG
+#if !ARRAY_DEBUG
+# undef NDEBUG
 # define NDEBUG
 #endif
 #include "ruby_assert.h"
 
 VALUE rb_cArray;
 
-static ID id_cmp, id_div, id_power;
+/* Flags of RArray
+ *
+ * 1:   RARRAY_EMBED_FLAG
+ *          The array is embedded (its contents follow the header, rather than
+ *          being on a separately allocated buffer).
+ * 2:   RARRAY_SHARED_FLAG (equal to ELTS_SHARED)
+ *          The array is shared. The buffer this array points to is owned by
+ *          another array (the shared root).
+ * if USE_RVARGC
+ * 3-9: RARRAY_EMBED_LEN
+ *          The length of the array when RARRAY_EMBED_FLAG is set.
+ * else
+ * 3-4: RARRAY_EMBED_LEN
+ *          The length of the array when RARRAY_EMBED_FLAG is set.
+ * endif
+ * 12:  RARRAY_SHARED_ROOT_FLAG
+ *          The array is a shared root that does reference counting. The buffer
+ *          this array points to is owned by this array but may be pointed to
+ *          by other arrays.
+ *          Note: Frozen arrays may be a shared root without this flag being
+ *                set. Frozen arrays do not have reference counting because
+ *                they cannot be modified. Not updating the reference count
+ *                improves copy-on-write performance. Their reference count is
+ *                assumed to be infinity.
+ * 13:  RARRAY_TRANSIENT_FLAG
+ *          The buffer of the array is allocated on the transient heap.
+ * 14:  RARRAY_PTR_IN_USE_FLAG
+ *          The buffer of the array is in use. This is only used during
+ *          debugging.
+ */
+
+/* for OPTIMIZED_CMP: */
+#define id_cmp idCmp
 
 #define ARY_DEFAULT_SIZE 16
 #define ARY_MAX_SIZE (LONG_MAX / (int)sizeof(VALUE))
+#define SMALL_ARRAY_LEN 16
 
-# define ARY_SHARED_P(ary) \
-    (assert(!FL_TEST((ary), ELTS_SHARED) || !FL_TEST((ary), RARRAY_EMBED_FLAG)), \
-     FL_TEST((ary),ELTS_SHARED)!=0)
-# define ARY_EMBED_P(ary) \
-    (assert(!FL_TEST((ary), ELTS_SHARED) || !FL_TEST((ary), RARRAY_EMBED_FLAG)), \
-     FL_TEST((ary), RARRAY_EMBED_FLAG)!=0)
+RBIMPL_ATTR_MAYBE_UNUSED()
+static int
+should_be_T_ARRAY(VALUE ary)
+{
+    return RB_TYPE_P(ary, T_ARRAY);
+}
 
 #define ARY_HEAP_PTR(a) (assert(!ARY_EMBED_P(a)), RARRAY(a)->as.heap.ptr)
 #define ARY_HEAP_LEN(a) (assert(!ARY_EMBED_P(a)), RARRAY(a)->as.heap.len)
+#define ARY_HEAP_CAPA(a) (assert(!ARY_EMBED_P(a)), assert(!ARY_SHARED_ROOT_P(a)), \
+                          RARRAY(a)->as.heap.aux.capa)
+
 #define ARY_EMBED_PTR(a) (assert(ARY_EMBED_P(a)), RARRAY(a)->as.ary)
 #define ARY_EMBED_LEN(a) \
     (assert(ARY_EMBED_P(a)), \
      (long)((RBASIC(a)->flags >> RARRAY_EMBED_LEN_SHIFT) & \
-	 (RARRAY_EMBED_LEN_MASK >> RARRAY_EMBED_LEN_SHIFT)))
-#define ARY_HEAP_SIZE(a) (assert(!ARY_EMBED_P(a)), assert(ARY_OWNS_HEAP_P(a)), RARRAY(a)->as.heap.aux.capa * sizeof(VALUE))
+         (RARRAY_EMBED_LEN_MASK >> RARRAY_EMBED_LEN_SHIFT)))
+#define ARY_HEAP_SIZE(a) (assert(!ARY_EMBED_P(a)), assert(ARY_OWNS_HEAP_P(a)), ARY_CAPA(a) * sizeof(VALUE))
+
+#define ARY_OWNS_HEAP_P(a) (assert(should_be_T_ARRAY((VALUE)(a))), \
+                            !FL_TEST_RAW((a), RARRAY_SHARED_FLAG|RARRAY_EMBED_FLAG))
 
-#define ARY_OWNS_HEAP_P(a) (!FL_TEST((a), ELTS_SHARED|RARRAY_EMBED_FLAG))
 #define FL_SET_EMBED(a) do { \
     assert(!ARY_SHARED_P(a)); \
     FL_SET((a), RARRAY_EMBED_FLAG); \
+    RARY_TRANSIENT_UNSET(a); \
+    ary_verify(a); \
 } while (0)
+
 #define FL_UNSET_EMBED(ary) FL_UNSET((ary), RARRAY_EMBED_FLAG|RARRAY_EMBED_LEN_MASK)
 #define FL_SET_SHARED(ary) do { \
     assert(!ARY_EMBED_P(ary)); \
-    FL_SET((ary), ELTS_SHARED); \
+    FL_SET((ary), RARRAY_SHARED_FLAG); \
 } while (0)
-#define FL_UNSET_SHARED(ary) FL_UNSET((ary), ELTS_SHARED)
+#define FL_UNSET_SHARED(ary) FL_UNSET((ary), RARRAY_SHARED_FLAG)
 
 #define ARY_SET_PTR(ary, p) do { \
     assert(!ARY_EMBED_P(ary)); \
@@ -65,7 +121,6 @@ static ID id_cmp, id_div, id_power;
 #define ARY_SET_EMBED_LEN(ary, n) do { \
     long tmp_n = (n); \
     assert(ARY_EMBED_P(ary)); \
-    assert(!OBJ_FROZEN(ary)); \
     RBASIC(ary)->flags &= ~RARRAY_EMBED_LEN_MASK; \
     RBASIC(ary)->flags |= (tmp_n) << RARRAY_EMBED_LEN_SHIFT; \
 } while (0)
@@ -97,8 +152,8 @@ static ID id_cmp, id_div, id_power;
     } \
 } while (0)
 
-#define ARY_CAPA(ary) (ARY_EMBED_P(ary) ? RARRAY_EMBED_LEN_MAX : \
-		       ARY_SHARED_ROOT_P(ary) ? RARRAY_LEN(ary) : RARRAY(ary)->as.heap.aux.capa)
+#define ARY_CAPA(ary) (ARY_EMBED_P(ary) ? ary_embed_capa(ary) : \
+                       ARY_SHARED_ROOT_P(ary) ? RARRAY_LEN(ary) : ARY_HEAP_CAPA(ary))
 #define ARY_SET_CAPA(ary, n) do { \
     assert(!ARY_EMBED_P(ary)); \
     assert(!ARY_SHARED_P(ary)); \
@@ -106,44 +161,185 @@ static ID id_cmp, id_div, id_power;
     RARRAY(ary)->as.heap.aux.capa = (n); \
 } while (0)
 
-#define ARY_SHARED(ary) (assert(ARY_SHARED_P(ary)), RARRAY(ary)->as.heap.aux.shared)
 #define ARY_SET_SHARED(ary, value) do { \
     const VALUE _ary_ = (ary); \
     const VALUE _value_ = (value); \
     assert(!ARY_EMBED_P(_ary_)); \
     assert(ARY_SHARED_P(_ary_)); \
-    assert(ARY_SHARED_ROOT_P(_value_)); \
-    RB_OBJ_WRITE(_ary_, &RARRAY(_ary_)->as.heap.aux.shared, _value_); \
+    assert(!OBJ_FROZEN(_ary_)); \
+    assert(ARY_SHARED_ROOT_P(_value_) || OBJ_FROZEN(_value_)); \
+    RB_OBJ_WRITE(_ary_, &RARRAY(_ary_)->as.heap.aux.shared_root, _value_); \
 } while (0)
-#define RARRAY_SHARED_ROOT_FLAG FL_USER5
-#define ARY_SHARED_ROOT_P(ary) (FL_TEST((ary), RARRAY_SHARED_ROOT_FLAG))
-#define ARY_SHARED_NUM(ary) \
-    (assert(ARY_SHARED_ROOT_P(ary)), RARRAY(ary)->as.heap.aux.capa)
-#define ARY_SHARED_OCCUPIED(ary) (ARY_SHARED_NUM(ary) == 1)
-#define ARY_SET_SHARED_NUM(ary, value) do { \
+
+#define ARY_SHARED_ROOT_OCCUPIED(ary) (!OBJ_FROZEN(ary) && ARY_SHARED_ROOT_REFCNT(ary) == 1)
+#define ARY_SET_SHARED_ROOT_REFCNT(ary, value) do { \
     assert(ARY_SHARED_ROOT_P(ary)); \
+    assert(!OBJ_FROZEN(ary)); \
+    assert((value) >= 0); \
     RARRAY(ary)->as.heap.aux.capa = (value); \
 } while (0)
 #define FL_SET_SHARED_ROOT(ary) do { \
+    assert(!OBJ_FROZEN(ary)); \
     assert(!ARY_EMBED_P(ary)); \
+    assert(!RARRAY_TRANSIENT_P(ary)); \
     FL_SET((ary), RARRAY_SHARED_ROOT_FLAG); \
 } while (0)
 
-#define ARY_SET(a, i, v) RARRAY_ASET((assert(!ARY_SHARED_P(a)), (a)), (i), (v))
+static inline void
+ARY_SET(VALUE a, long i, VALUE v)
+{
+    assert(!ARY_SHARED_P(a));
+    assert(!OBJ_FROZEN(a));
+
+    RARRAY_ASET(a, i, v);
+}
+#undef RARRAY_ASET
+
+static long
+ary_embed_capa(VALUE ary)
+{
+#if USE_RVARGC
+    size_t size = rb_gc_obj_slot_size(ary) - offsetof(struct RArray, as.ary);
+    assert(size % sizeof(VALUE) == 0);
+    return size / sizeof(VALUE);
+#else
+    return RARRAY_EMBED_LEN_MAX;
+#endif
+}
+
+static size_t
+ary_embed_size(long capa)
+{
+    return offsetof(struct RArray, as.ary) + (sizeof(VALUE) * capa);
+}
+
+static bool
+ary_embeddable_p(long capa)
+{
+#if USE_RVARGC
+    return rb_gc_size_allocatable_p(ary_embed_size(capa));
+#else
+    return capa <= RARRAY_EMBED_LEN_MAX;
+#endif
+}
+
+bool
+rb_ary_embeddable_p(VALUE ary)
+{
+    /* An array cannot be turned embeddable when the array is:
+     *  - Shared root: other objects may point to the buffer of this array
+     *    so we cannot make it embedded.
+     *  - Frozen: this array may also be a shared root without the shared root
+     *    flag.
+     *  - Shared: we don't want to re-embed an array that points to a shared
+     *    root (to save memory).
+     */
+    return !(ARY_SHARED_ROOT_P(ary) || OBJ_FROZEN(ary) || ARY_SHARED_P(ary));
+}
+
+size_t
+rb_ary_size_as_embedded(VALUE ary)
+{
+    size_t real_size;
+
+    if (ARY_EMBED_P(ary)) {
+        real_size = ary_embed_size(ARY_EMBED_LEN(ary));
+    }
+    else if (rb_ary_embeddable_p(ary)) {
+        real_size = ary_embed_size(ARY_HEAP_CAPA(ary));
+    }
+    else {
+        real_size = sizeof(struct RArray);
+    }
+    return real_size;
+}
+
+
+#if ARRAY_DEBUG
+#define ary_verify(ary) ary_verify_(ary, __FILE__, __LINE__)
+
+static VALUE
+ary_verify_(VALUE ary, const char *file, int line)
+{
+    assert(RB_TYPE_P(ary, T_ARRAY));
+
+    if (ARY_SHARED_P(ary)) {
+        VALUE root = ARY_SHARED_ROOT(ary);
+        const VALUE *ptr = ARY_HEAP_PTR(ary);
+        const VALUE *root_ptr = RARRAY_CONST_PTR_TRANSIENT(root);
+        long len = ARY_HEAP_LEN(ary), root_len = RARRAY_LEN(root);
+        assert(ARY_SHARED_ROOT_P(root) || OBJ_FROZEN(root));
+        assert(root_ptr <= ptr && ptr + len <= root_ptr + root_len);
+        ary_verify(root);
+    }
+    else if (ARY_EMBED_P(ary)) {
+        assert(!RARRAY_TRANSIENT_P(ary));
+        assert(!ARY_SHARED_P(ary));
+        assert(RARRAY_LEN(ary) <= ary_embed_capa(ary));
+    }
+    else {
+#if 1
+        const VALUE *ptr = RARRAY_CONST_PTR_TRANSIENT(ary);
+        long i, len = RARRAY_LEN(ary);
+        volatile VALUE v;
+        if (len > 1) len = 1; /* check only HEAD */
+        for (i=0; i<len; i++) {
+            v = ptr[i]; /* access check */
+        }
+        v = v;
+#endif
+    }
+
+#if USE_TRANSIENT_HEAP
+    if (RARRAY_TRANSIENT_P(ary)) {
+        assert(rb_transient_heap_managed_ptr_p(RARRAY_CONST_PTR_TRANSIENT(ary)));
+    }
+#endif
+
+    rb_transient_heap_verify();
+
+    return ary;
+}
+
+void
+rb_ary_verify(VALUE ary)
+{
+    ary_verify(ary);
+}
+#else
+#define ary_verify(ary) ((void)0)
+#endif
+
+VALUE *
+rb_ary_ptr_use_start(VALUE ary)
+{
+#if ARRAY_DEBUG
+    FL_SET_RAW(ary, RARRAY_PTR_IN_USE_FLAG);
+#endif
+    return (VALUE *)RARRAY_CONST_PTR_TRANSIENT(ary);
+}
+
+void
+rb_ary_ptr_use_end(VALUE ary)
+{
+#if ARRAY_DEBUG
+    FL_UNSET_RAW(ary, RARRAY_PTR_IN_USE_FLAG);
+#endif
+}
 
 void
-rb_mem_clear(register VALUE *mem, register long size)
+rb_mem_clear(VALUE *mem, long size)
 {
     while (size--) {
-	*mem++ = Qnil;
+        *mem++ = Qnil;
     }
 }
 
 static void
 ary_mem_clear(VALUE ary, long beg, long size)
 {
-    RARRAY_PTR_USE(ary, ptr, {
-	rb_mem_clear(ptr + beg, size);
+    RARRAY_PTR_USE_TRANSIENT(ary, ptr, {
+        rb_mem_clear(ptr + beg, size);
     });
 }
 
@@ -151,44 +347,38 @@ static inline void
 memfill(register VALUE *mem, register long size, register VALUE val)
 {
     while (size--) {
-	*mem++ = val;
+        *mem++ = val;
     }
 }
 
 static void
 ary_memfill(VALUE ary, long beg, long size, VALUE val)
 {
-    RARRAY_PTR_USE(ary, ptr, {
-	memfill(ptr + beg, size, val);
-	RB_OBJ_WRITTEN(ary, Qundef, val);
+    RARRAY_PTR_USE_TRANSIENT(ary, ptr, {
+        memfill(ptr + beg, size, val);
+        RB_OBJ_WRITTEN(ary, Qundef, val);
     });
 }
 
 static void
 ary_memcpy0(VALUE ary, long beg, long argc, const VALUE *argv, VALUE buff_owner_ary)
 {
-#if 1
     assert(!ARY_SHARED_P(buff_owner_ary));
 
     if (argc > (int)(128/sizeof(VALUE)) /* is magic number (cache line size) */) {
-	rb_gc_writebarrier_remember(buff_owner_ary);
-	RARRAY_PTR_USE(ary, ptr, {
-	    MEMCPY(ptr+beg, argv, VALUE, argc);
-	});
+        rb_gc_writebarrier_remember(buff_owner_ary);
+        RARRAY_PTR_USE_TRANSIENT(ary, ptr, {
+            MEMCPY(ptr+beg, argv, VALUE, argc);
+        });
     }
     else {
-	int i;
-	RARRAY_PTR_USE(ary, ptr, {
-	    for (i=0; i<argc; i++) {
-		RB_OBJ_WRITE(buff_owner_ary, &ptr[i+beg], argv[i]);
-	    }
-	});
+        int i;
+        RARRAY_PTR_USE_TRANSIENT(ary, ptr, {
+            for (i=0; i<argc; i++) {
+                RB_OBJ_WRITE(buff_owner_ary, &ptr[i+beg], argv[i]);
+            }
+        });
     }
-#else
-    /* giveup write barrier (traditional way) */
-    RARRAY_PTR(buff_owner_ary);
-    MEMCPY(RARRAY_PTR(ary)+beg, argv, VALUE, argc);
-#endif
 }
 
 static void
@@ -197,49 +387,198 @@ ary_memcpy(VALUE ary, long beg, long argc, const VALUE *argv)
     ary_memcpy0(ary, beg, argc, argv, ary);
 }
 
+static VALUE *
+ary_heap_alloc(VALUE ary, size_t capa)
+{
+    VALUE *ptr = rb_transient_heap_alloc(ary, sizeof(VALUE) * capa);
+
+    if (ptr != NULL) {
+        RARY_TRANSIENT_SET(ary);
+    }
+    else {
+        RARY_TRANSIENT_UNSET(ary);
+        ptr = ALLOC_N(VALUE, capa);
+    }
+
+    return ptr;
+}
+
+static void
+ary_heap_free_ptr(VALUE ary, const VALUE *ptr, long size)
+{
+    if (RARRAY_TRANSIENT_P(ary)) {
+        /* ignore it */
+    }
+    else {
+        ruby_sized_xfree((void *)ptr, size);
+    }
+}
+
+static void
+ary_heap_free(VALUE ary)
+{
+    if (RARRAY_TRANSIENT_P(ary)) {
+        RARY_TRANSIENT_UNSET(ary);
+    }
+    else {
+        ary_heap_free_ptr(ary, ARY_HEAP_PTR(ary), ARY_HEAP_SIZE(ary));
+    }
+}
+
+static size_t
+ary_heap_realloc(VALUE ary, size_t new_capa)
+{
+    size_t alloc_capa = new_capa;
+    size_t old_capa = ARY_HEAP_CAPA(ary);
+
+    if (RARRAY_TRANSIENT_P(ary)) {
+        if (new_capa <= old_capa) {
+            /* do nothing */
+            alloc_capa = old_capa;
+        }
+        else {
+            VALUE *new_ptr = rb_transient_heap_alloc(ary, sizeof(VALUE) * new_capa);
+
+            if (new_ptr == NULL) {
+                new_ptr = ALLOC_N(VALUE, new_capa);
+                RARY_TRANSIENT_UNSET(ary);
+            }
+
+            MEMCPY(new_ptr, ARY_HEAP_PTR(ary), VALUE, old_capa);
+            ARY_SET_PTR(ary, new_ptr);
+        }
+    }
+    else {
+        SIZED_REALLOC_N(RARRAY(ary)->as.heap.ptr, VALUE, new_capa, old_capa);
+    }
+    ary_verify(ary);
+
+    return alloc_capa;
+}
+
+#if USE_TRANSIENT_HEAP
+static inline void
+rb_ary_transient_heap_evacuate_(VALUE ary, int transient, int promote)
+{
+    if (transient) {
+        assert(!ARY_SHARED_ROOT_P(ary));
+
+        VALUE *new_ptr;
+        const VALUE *old_ptr = ARY_HEAP_PTR(ary);
+        long capa = ARY_HEAP_CAPA(ary);
+
+        assert(ARY_OWNS_HEAP_P(ary));
+        assert(RARRAY_TRANSIENT_P(ary));
+        assert(!ARY_PTR_USING_P(ary));
+
+        if (promote) {
+            new_ptr = ALLOC_N(VALUE, capa);
+            RARY_TRANSIENT_UNSET(ary);
+        }
+        else {
+            new_ptr = ary_heap_alloc(ary, capa);
+        }
+
+        MEMCPY(new_ptr, old_ptr, VALUE, capa);
+        /* do not use ARY_SET_PTR() because they assert !frozen */
+        RARRAY(ary)->as.heap.ptr = new_ptr;
+    }
+
+    ary_verify(ary);
+}
+
+void
+rb_ary_transient_heap_evacuate(VALUE ary, int promote)
+{
+    rb_ary_transient_heap_evacuate_(ary, RARRAY_TRANSIENT_P(ary), promote);
+}
+
+void
+rb_ary_detransient(VALUE ary)
+{
+    assert(RARRAY_TRANSIENT_P(ary));
+    rb_ary_transient_heap_evacuate_(ary, TRUE, TRUE);
+}
+#else
+void
+rb_ary_detransient(VALUE ary)
+{
+    /* do nothing */
+}
+#endif
+
+void
+rb_ary_make_embedded(VALUE ary)
+{
+    assert(rb_ary_embeddable_p(ary));
+    if (!ARY_EMBED_P(ary)) {
+        const VALUE *buf = ARY_HEAP_PTR(ary);
+        long len = ARY_HEAP_LEN(ary);
+        bool was_transient = RARRAY_TRANSIENT_P(ary);
+
+        // FL_SET_EMBED also unsets the transient flag
+        FL_SET_EMBED(ary);
+        ARY_SET_EMBED_LEN(ary, len);
+
+        MEMCPY((void *)ARY_EMBED_PTR(ary), (void *)buf, VALUE, len);
+
+        if (!was_transient) {
+            ary_heap_free_ptr(ary, buf, len * sizeof(VALUE));
+        }
+    }
+}
+
 static void
 ary_resize_capa(VALUE ary, long capacity)
 {
     assert(RARRAY_LEN(ary) <= capacity);
     assert(!OBJ_FROZEN(ary));
     assert(!ARY_SHARED_P(ary));
-    if (capacity > RARRAY_EMBED_LEN_MAX) {
+
+    if (capacity > ary_embed_capa(ary)) {
+        size_t new_capa = capacity;
         if (ARY_EMBED_P(ary)) {
             long len = ARY_EMBED_LEN(ary);
-            VALUE *ptr = ALLOC_N(VALUE, (capacity));
+            VALUE *ptr = ary_heap_alloc(ary, capacity);
+
             MEMCPY(ptr, ARY_EMBED_PTR(ary), VALUE, len);
             FL_UNSET_EMBED(ary);
             ARY_SET_PTR(ary, ptr);
             ARY_SET_HEAP_LEN(ary, len);
         }
         else {
-	    SIZED_REALLOC_N(RARRAY(ary)->as.heap.ptr, VALUE, capacity, RARRAY(ary)->as.heap.aux.capa);
+            new_capa = ary_heap_realloc(ary, capacity);
         }
-        ARY_SET_CAPA(ary, (capacity));
+        ARY_SET_CAPA(ary, new_capa);
     }
     else {
         if (!ARY_EMBED_P(ary)) {
-            long len = RARRAY_LEN(ary);
-	    const VALUE *ptr = RARRAY_CONST_PTR(ary);
+            long len = ARY_HEAP_LEN(ary);
+            long old_capa = ARY_HEAP_CAPA(ary);
+            const VALUE *ptr = ARY_HEAP_PTR(ary);
 
-	    if (len > capacity) len = capacity;
+            if (len > capacity) len = capacity;
             MEMCPY((VALUE *)RARRAY(ary)->as.ary, ptr, VALUE, len);
+            ary_heap_free_ptr(ary, ptr, old_capa);
+
             FL_SET_EMBED(ary);
             ARY_SET_LEN(ary, len);
-	    ruby_xfree((VALUE *)ptr);
         }
     }
+
+    ary_verify(ary);
 }
 
 static inline void
 ary_shrink_capa(VALUE ary)
 {
     long capacity = ARY_HEAP_LEN(ary);
-    long old_capa = RARRAY(ary)->as.heap.aux.capa;
+    long old_capa = ARY_HEAP_CAPA(ary);
     assert(!ARY_SHARED_P(ary));
     assert(old_capa >= capacity);
-    if (old_capa > capacity)
-	REALLOC_N(RARRAY(ary)->as.heap.ptr, VALUE, capacity);
+    if (old_capa > capacity) ary_heap_realloc(ary, capacity);
+
+    ary_verify(ary);
 }
 
 static void
@@ -248,106 +587,121 @@ ary_double_capa(VALUE ary, long min)
     long new_capa = ARY_CAPA(ary) / 2;
 
     if (new_capa < ARY_DEFAULT_SIZE) {
-	new_capa = ARY_DEFAULT_SIZE;
+        new_capa = ARY_DEFAULT_SIZE;
     }
     if (new_capa >= ARY_MAX_SIZE - min) {
-	new_capa = (ARY_MAX_SIZE - min) / 2;
+        new_capa = (ARY_MAX_SIZE - min) / 2;
     }
     new_capa += min;
     ary_resize_capa(ary, new_capa);
+
+    ary_verify(ary);
 }
 
 static void
-rb_ary_decrement_share(VALUE shared)
+rb_ary_decrement_share(VALUE shared_root)
 {
-    if (shared) {
-	long num = ARY_SHARED_NUM(shared) - 1;
-	if (num == 0) {
-	    rb_ary_free(shared);
-	    rb_gc_force_recycle(shared);
-	}
-	else if (num > 0) {
-	    ARY_SET_SHARED_NUM(shared, num);
-	}
+    if (!OBJ_FROZEN(shared_root)) {
+        long num = ARY_SHARED_ROOT_REFCNT(shared_root);
+        ARY_SET_SHARED_ROOT_REFCNT(shared_root, num - 1);
     }
 }
 
 static void
 rb_ary_unshare(VALUE ary)
 {
-    VALUE shared = RARRAY(ary)->as.heap.aux.shared;
-    rb_ary_decrement_share(shared);
+    VALUE shared_root = ARY_SHARED_ROOT(ary);
+    rb_ary_decrement_share(shared_root);
     FL_UNSET_SHARED(ary);
 }
 
-static inline void
-rb_ary_unshare_safe(VALUE ary)
+static void
+rb_ary_reset(VALUE ary)
 {
-    if (ARY_SHARED_P(ary) && !ARY_EMBED_P(ary)) {
-	rb_ary_unshare(ary);
+    if (ARY_OWNS_HEAP_P(ary)) {
+        ary_heap_free(ary);
+    }
+    else if (ARY_SHARED_P(ary)) {
+        rb_ary_unshare(ary);
     }
+
+    FL_SET_EMBED(ary);
+    ARY_SET_EMBED_LEN(ary, 0);
 }
 
 static VALUE
-rb_ary_increment_share(VALUE shared)
+rb_ary_increment_share(VALUE shared_root)
 {
-    long num = ARY_SHARED_NUM(shared);
-    if (num >= 0) {
-	ARY_SET_SHARED_NUM(shared, num + 1);
+    if (!OBJ_FROZEN(shared_root)) {
+        long num = ARY_SHARED_ROOT_REFCNT(shared_root);
+        assert(num >= 0);
+        ARY_SET_SHARED_ROOT_REFCNT(shared_root, num + 1);
     }
-    return shared;
+    return shared_root;
 }
 
 static void
-rb_ary_set_shared(VALUE ary, VALUE shared)
+rb_ary_set_shared(VALUE ary, VALUE shared_root)
 {
-    rb_ary_increment_share(shared);
+    rb_ary_increment_share(shared_root);
     FL_SET_SHARED(ary);
-    ARY_SET_SHARED(ary, shared);
+    RB_DEBUG_COUNTER_INC(obj_ary_shared_create);
+    ARY_SET_SHARED(ary, shared_root);
 }
 
 static inline void
 rb_ary_modify_check(VALUE ary)
 {
     rb_check_frozen(ary);
+    ary_verify(ary);
 }
 
 void
-rb_ary_modify(VALUE ary)
+rb_ary_cancel_sharing(VALUE ary)
 {
-    rb_ary_modify_check(ary);
     if (ARY_SHARED_P(ary)) {
-	long shared_len, len = RARRAY_LEN(ary);
-	VALUE shared = ARY_SHARED(ary);
-        if (len <= RARRAY_EMBED_LEN_MAX) {
-	    const VALUE *ptr = ARY_HEAP_PTR(ary);
+        long shared_len, len = RARRAY_LEN(ary);
+        VALUE shared_root = ARY_SHARED_ROOT(ary);
+
+        ary_verify(shared_root);
+
+        if (len <= ary_embed_capa(ary)) {
+            const VALUE *ptr = ARY_HEAP_PTR(ary);
             FL_UNSET_SHARED(ary);
             FL_SET_EMBED(ary);
-	    MEMCPY((VALUE *)ARY_EMBED_PTR(ary), ptr, VALUE, len);
-            rb_ary_decrement_share(shared);
+            MEMCPY((VALUE *)ARY_EMBED_PTR(ary), ptr, VALUE, len);
+            rb_ary_decrement_share(shared_root);
             ARY_SET_EMBED_LEN(ary, len);
         }
-	else if (ARY_SHARED_OCCUPIED(shared) && len > ((shared_len = RARRAY_LEN(shared))>>1)) {
-	    long shift = RARRAY_CONST_PTR(ary) - RARRAY_CONST_PTR(shared);
-	    FL_UNSET_SHARED(ary);
-	    ARY_SET_PTR(ary, RARRAY_CONST_PTR(shared));
-	    ARY_SET_CAPA(ary, shared_len);
-	    RARRAY_PTR_USE(ary, ptr, {
-		MEMMOVE(ptr, ptr+shift, VALUE, len);
-	    });
-	    FL_SET_EMBED(shared);
-	    rb_ary_decrement_share(shared);
-	}
+        else if (ARY_SHARED_ROOT_OCCUPIED(shared_root) && len > ((shared_len = RARRAY_LEN(shared_root))>>1)) {
+            long shift = RARRAY_CONST_PTR_TRANSIENT(ary) - RARRAY_CONST_PTR_TRANSIENT(shared_root);
+            FL_UNSET_SHARED(ary);
+            ARY_SET_PTR(ary, RARRAY_CONST_PTR_TRANSIENT(shared_root));
+            ARY_SET_CAPA(ary, shared_len);
+            RARRAY_PTR_USE_TRANSIENT(ary, ptr, {
+                MEMMOVE(ptr, ptr+shift, VALUE, len);
+            });
+            FL_SET_EMBED(shared_root);
+            rb_ary_decrement_share(shared_root);
+        }
         else {
-            VALUE *ptr = ALLOC_N(VALUE, len);
-            MEMCPY(ptr, RARRAY_CONST_PTR(ary), VALUE, len);
+            VALUE *ptr = ary_heap_alloc(ary, len);
+            MEMCPY(ptr, ARY_HEAP_PTR(ary), VALUE, len);
             rb_ary_unshare(ary);
             ARY_SET_CAPA(ary, len);
             ARY_SET_PTR(ary, ptr);
         }
 
-	rb_gc_writebarrier_remember(ary);
+        rb_gc_writebarrier_remember(ary);
     }
+    ary_verify(ary);
+}
+
+void
+rb_ary_modify(VALUE ary)
+{
+    rb_ary_modify_check(ary);
+    rb_ary_cancel_sharing(ary);
 }
 
 static VALUE
@@ -358,45 +712,58 @@ ary_ensure_room_for_push(VALUE ary, long add_len)
     long capa;
 
     if (old_len > ARY_MAX_SIZE - add_len) {
-	rb_raise(rb_eIndexError, "index %ld too big", new_len);
+        rb_raise(rb_eIndexError, "index %ld too big", new_len);
     }
     if (ARY_SHARED_P(ary)) {
-	if (new_len > RARRAY_EMBED_LEN_MAX) {
-	    VALUE shared = ARY_SHARED(ary);
-	    if (ARY_SHARED_OCCUPIED(shared)) {
-		if (RARRAY_CONST_PTR(ary) - RARRAY_CONST_PTR(shared) + new_len <= RARRAY_LEN(shared)) {
-		    rb_ary_modify_check(ary);
-		    return shared;
-		}
-		else {
-		    /* if array is shared, then it is likely it participate in push/shift pattern */
-		    rb_ary_modify(ary);
-		    capa = ARY_CAPA(ary);
-		    if (new_len > capa - (capa >> 6)) {
-			ary_double_capa(ary, new_len);
-		    }
-		    return ary;
-		}
-	    }
-	}
+        if (new_len > ary_embed_capa(ary)) {
+            VALUE shared_root = ARY_SHARED_ROOT(ary);
+            if (ARY_SHARED_ROOT_OCCUPIED(shared_root)) {
+                if (ARY_HEAP_PTR(ary) - RARRAY_CONST_PTR_TRANSIENT(shared_root) + new_len <= RARRAY_LEN(shared_root)) {
+                    rb_ary_modify_check(ary);
+
+                    ary_verify(ary);
+                    ary_verify(shared_root);
+                    return shared_root;
+                }
+                else {
+                    /* if array is shared, then it is likely it participate in push/shift pattern */
+                    rb_ary_modify(ary);
+                    capa = ARY_CAPA(ary);
+                    if (new_len > capa - (capa >> 6)) {
+                        ary_double_capa(ary, new_len);
+                    }
+                    ary_verify(ary);
+                    return ary;
+                }
+            }
+        }
+        ary_verify(ary);
+        rb_ary_modify(ary);
+    }
+    else {
+        rb_ary_modify_check(ary);
     }
-    rb_ary_modify(ary);
     capa = ARY_CAPA(ary);
     if (new_len > capa) {
-	ary_double_capa(ary, new_len);
+        ary_double_capa(ary, new_len);
     }
 
+    ary_verify(ary);
     return ary;
 }
 
 /*
  *  call-seq:
- *      ary.freeze -> ary
+ *    array.freeze -> self
+ *
+ *  Freezes +self+; returns +self+:
  *
- *  Calls Object#freeze on +ary+ to prevent any further
- *  modification. A RuntimeError will be raised if a modification
- *  attempt is made.
+ *    a = []
+ *    a.frozen? # => false
+ *    a.freeze
+ *    a.frozen? # => true
  *
+ *  An attempt to modify a frozen \Array raises FrozenError.
  */
 
 VALUE
@@ -405,21 +772,6 @@ rb_ary_freeze(VALUE ary)
     return rb_obj_freeze(ary);
 }
 
-/*
- *  call-seq:
- *     ary.frozen?  -> true or false
- *
- *  Return +true+ if this array is frozen (or temporarily frozen
- *  while being sorted). See also Object#frozen?
- */
-
-static VALUE
-rb_ary_frozen_p(VALUE ary)
-{
-    if (OBJ_FROZEN(ary)) return Qtrue;
-    return Qfalse;
-}
-
 /* This can be used to take a snapshot of an array (with
    e.g. rb_ary_replace) and check later whether the array has been
    modified from the snapshot.  The snapshot is cheap, though if
@@ -431,18 +783,25 @@ VALUE
 rb_ary_shared_with_p(VALUE ary1, VALUE ary2)
 {
     if (!ARY_EMBED_P(ary1) && ARY_SHARED_P(ary1) &&
-	!ARY_EMBED_P(ary2) && ARY_SHARED_P(ary2) &&
-	RARRAY(ary1)->as.heap.aux.shared == RARRAY(ary2)->as.heap.aux.shared &&
-	RARRAY(ary1)->as.heap.len == RARRAY(ary2)->as.heap.len) {
-	return Qtrue;
+            !ARY_EMBED_P(ary2) && ARY_SHARED_P(ary2) &&
+            ARY_SHARED_ROOT(ary1) == ARY_SHARED_ROOT(ary2) &&
+            ARY_HEAP_LEN(ary1) == ARY_HEAP_LEN(ary2)) {
+        return Qtrue;
     }
     return Qfalse;
 }
 
 static VALUE
-ary_alloc(VALUE klass)
+ary_alloc_embed(VALUE klass, long capa)
 {
-    NEWOBJ_OF(ary, struct RArray, klass, T_ARRAY | RARRAY_EMBED_FLAG | (RGENGC_WB_PROTECTED_ARRAY ? FL_WB_PROTECTED : 0));
+    size_t size = ary_embed_size(capa);
+    assert(rb_gc_size_allocatable_p(size));
+#if !USE_RVARGC
+    assert(size <= sizeof(struct RArray));
+#endif
+    RVARGC_NEWOBJ_OF(ary, struct RArray, klass,
+                     T_ARRAY | RARRAY_EMBED_FLAG | (RGENGC_WB_PROTECTED_ARRAY ? FL_WB_PROTECTED : 0),
+                     size);
     /* Created array is:
      *   FL_SET_EMBED((VALUE)ary);
      *   ARY_SET_EMBED_LEN((VALUE)ary, 0);
@@ -451,10 +810,19 @@ ary_alloc(VALUE klass)
 }
 
 static VALUE
+ary_alloc_heap(VALUE klass)
+{
+    RVARGC_NEWOBJ_OF(ary, struct RArray, klass,
+                     T_ARRAY | (RGENGC_WB_PROTECTED_ARRAY ? FL_WB_PROTECTED : 0),
+                     sizeof(struct RArray));
+    return (VALUE)ary;
+}
+
+static VALUE
 empty_ary_alloc(VALUE klass)
 {
     RUBY_DTRACE_CREATE_HOOK(ARRAY, 0);
-    return ary_alloc(klass);
+    return ary_alloc_embed(klass, 0);
 }
 
 static VALUE
@@ -463,20 +831,24 @@ ary_new(VALUE klass, long capa)
     VALUE ary,*ptr;
 
     if (capa < 0) {
-	rb_raise(rb_eArgError, "negative array size (or size too big)");
+        rb_raise(rb_eArgError, "negative array size (or size too big)");
     }
     if (capa > ARY_MAX_SIZE) {
-	rb_raise(rb_eArgError, "array size too big");
+        rb_raise(rb_eArgError, "array size too big");
     }
 
     RUBY_DTRACE_CREATE_HOOK(ARRAY, capa);
 
-    ary = ary_alloc(klass);
-    if (capa > RARRAY_EMBED_LEN_MAX) {
-	ptr = ALLOC_N(VALUE, capa);
-        FL_UNSET_EMBED(ary);
-        ARY_SET_PTR(ary, ptr);
+    if (ary_embeddable_p(capa)) {
+        ary = ary_alloc_embed(klass, capa);
+    }
+    else {
+        ary = ary_alloc_heap(klass);
         ARY_SET_CAPA(ary, capa);
+        assert(!ARY_EMBED_P(ary));
+
+        ptr = ary_heap_alloc(ary, capa);
+        ARY_SET_PTR(ary, ptr);
         ARY_SET_HEAP_LEN(ary, 0);
     }
 
@@ -492,7 +864,7 @@ rb_ary_new_capa(long capa)
 VALUE
 rb_ary_new(void)
 {
-    return rb_ary_new2(RARRAY_EMBED_LEN_MAX);
+    return rb_ary_new_capa(0);
 }
 
 VALUE
@@ -506,7 +878,7 @@ VALUE
 
     va_start(ar, n);
     for (i=0; i<n; i++) {
-	ARY_SET(ary, i, va_arg(ar, VALUE));
+        ARY_SET(ary, i, va_arg(ar, VALUE));
     }
     va_end(ar);
 
@@ -514,30 +886,109 @@ VALUE
     return ary;
 }
 
+MJIT_FUNC_EXPORTED VALUE
+rb_ary_tmp_new_from_values(VALUE klass, long n, const VALUE *elts)
+{
+    VALUE ary;
+
+    ary = ary_new(klass, n);
+    if (n > 0 && elts) {
+        ary_memcpy(ary, 0, n, elts);
+        ARY_SET_LEN(ary, n);
+    }
+
+    return ary;
+}
+
 VALUE
 rb_ary_new_from_values(long n, const VALUE *elts)
 {
+    return rb_ary_tmp_new_from_values(rb_cArray, n, elts);
+}
+
+static VALUE
+ec_ary_alloc_embed(rb_execution_context_t *ec, VALUE klass, long capa)
+{
+    size_t size = ary_embed_size(capa);
+    assert(rb_gc_size_allocatable_p(size));
+#if !USE_RVARGC
+    assert(size <= sizeof(struct RArray));
+#endif
+    RB_RVARGC_EC_NEWOBJ_OF(ec, ary, struct RArray, klass,
+                           T_ARRAY | RARRAY_EMBED_FLAG | (RGENGC_WB_PROTECTED_ARRAY ? FL_WB_PROTECTED : 0),
+                           size);
+    /* Created array is:
+     *   FL_SET_EMBED((VALUE)ary);
+     *   ARY_SET_EMBED_LEN((VALUE)ary, 0);
+     */
+    return (VALUE)ary;
+}
+
+static VALUE
+ec_ary_alloc_heap(rb_execution_context_t *ec, VALUE klass)
+{
+    RB_RVARGC_EC_NEWOBJ_OF(ec, ary, struct RArray, klass,
+                           T_ARRAY | (RGENGC_WB_PROTECTED_ARRAY ? FL_WB_PROTECTED : 0),
+                           sizeof(struct RArray));
+    return (VALUE)ary;
+}
+
+static VALUE
+ec_ary_new(rb_execution_context_t *ec, VALUE klass, long capa)
+{
+    VALUE ary,*ptr;
+
+    if (capa < 0) {
+        rb_raise(rb_eArgError, "negative array size (or size too big)");
+    }
+    if (capa > ARY_MAX_SIZE) {
+        rb_raise(rb_eArgError, "array size too big");
+    }
+
+    RUBY_DTRACE_CREATE_HOOK(ARRAY, capa);
+
+    if (ary_embeddable_p(capa)) {
+        ary = ec_ary_alloc_embed(ec, klass, capa);
+    }
+    else {
+        ary = ec_ary_alloc_heap(ec, klass);
+        ARY_SET_CAPA(ary, capa);
+        assert(!ARY_EMBED_P(ary));
+
+        ptr = ary_heap_alloc(ary, capa);
+        ARY_SET_PTR(ary, ptr);
+        ARY_SET_HEAP_LEN(ary, 0);
+    }
+
+    return ary;
+}
+
+VALUE
+rb_ec_ary_new_from_values(rb_execution_context_t *ec, long n, const VALUE *elts)
+{
     VALUE ary;
 
-    ary = rb_ary_new2(n);
+    ary = ec_ary_new(ec, rb_cArray, n);
     if (n > 0 && elts) {
-	ary_memcpy(ary, 0, n, elts);
-	ARY_SET_LEN(ary, n);
+        ary_memcpy(ary, 0, n, elts);
+        ARY_SET_LEN(ary, n);
     }
 
     return ary;
 }
 
 VALUE
-rb_ary_tmp_new(long capa)
+rb_ary_hidden_new(long capa)
 {
-    return ary_new(0, capa);
+    VALUE ary = ary_new(0, capa);
+    rb_ary_transient_heap_evacuate(ary, TRUE);
+    return ary;
 }
 
 VALUE
-rb_ary_tmp_new_fill(long capa)
+rb_ary_hidden_new_fill(long capa)
 {
-    VALUE ary = ary_new(0, capa);
+    VALUE ary = rb_ary_hidden_new(capa);
     ary_memfill(ary, 0, capa, Qnil);
     ARY_SET_LEN(ary, capa);
     return ary;
@@ -547,7 +998,29 @@ void
 rb_ary_free(VALUE ary)
 {
     if (ARY_OWNS_HEAP_P(ary)) {
-	ruby_sized_xfree((void *)ARY_HEAP_PTR(ary), ARY_HEAP_SIZE(ary));
+        if (USE_DEBUG_COUNTER &&
+            !ARY_SHARED_ROOT_P(ary) &&
+            ARY_HEAP_CAPA(ary) > RARRAY_LEN(ary)) {
+            RB_DEBUG_COUNTER_INC(obj_ary_extracapa);
+        }
+
+        if (RARRAY_TRANSIENT_P(ary)) {
+            RB_DEBUG_COUNTER_INC(obj_ary_transient);
+        }
+        else {
+            RB_DEBUG_COUNTER_INC(obj_ary_ptr);
+            ary_heap_free(ary);
+        }
+    }
+    else {
+        RB_DEBUG_COUNTER_INC(obj_ary_embed);
+    }
+
+    if (ARY_SHARED_P(ary)) {
+        RB_DEBUG_COUNTER_INC(obj_ary_shared);
+    }
+    if (ARY_SHARED_ROOT_P(ary) && ARY_SHARED_ROOT_OCCUPIED(ary)) {
+        RB_DEBUG_COUNTER_INC(obj_ary_shared_root_occupied);
     }
 }
 
@@ -555,51 +1028,69 @@ RUBY_FUNC_EXPORTED size_t
 rb_ary_memsize(VALUE ary)
 {
     if (ARY_OWNS_HEAP_P(ary)) {
-	return RARRAY(ary)->as.heap.aux.capa * sizeof(VALUE);
+        return ARY_CAPA(ary) * sizeof(VALUE);
     }
     else {
-	return 0;
+        return 0;
     }
 }
 
-static inline void
-ary_discard(VALUE ary)
-{
-    rb_ary_free(ary);
-    RBASIC(ary)->flags |= RARRAY_EMBED_FLAG;
-    RBASIC(ary)->flags &= ~RARRAY_EMBED_LEN_MASK;
-}
-
 static VALUE
 ary_make_shared(VALUE ary)
 {
-    assert(!ARY_EMBED_P(ary));
+    assert(USE_RVARGC || !ARY_EMBED_P(ary));
+    ary_verify(ary);
+
     if (ARY_SHARED_P(ary)) {
-	return ARY_SHARED(ary);
+        return ARY_SHARED_ROOT(ary);
     }
     else if (ARY_SHARED_ROOT_P(ary)) {
-	return ary;
+        return ary;
     }
     else if (OBJ_FROZEN(ary)) {
-	ary_shrink_capa(ary);
-	FL_SET_SHARED_ROOT(ary);
-	ARY_SET_SHARED_NUM(ary, 1);
-	return ary;
+        if (!ARY_EMBED_P(ary)) {
+            rb_ary_transient_heap_evacuate(ary, TRUE);
+            ary_shrink_capa(ary);
+        }
+        return ary;
     }
     else {
-	long capa = ARY_CAPA(ary), len = RARRAY_LEN(ary);
-	NEWOBJ_OF(shared, struct RArray, 0, T_ARRAY | (RGENGC_WB_PROTECTED_ARRAY ? FL_WB_PROTECTED : 0));
-        FL_UNSET_EMBED(shared);
+        rb_ary_transient_heap_evacuate(ary, TRUE);
+
+        long capa = ARY_CAPA(ary);
+        long len = RARRAY_LEN(ary);
+
+        /* Shared roots cannot be embedded because the reference count
+         * (refcnt) is stored in as.heap.aux.capa. */
+        VALUE shared = ary_alloc_heap(0);
+        FL_SET_SHARED_ROOT(shared);
+
+        if (ARY_EMBED_P(ary)) {
+            /* Cannot use ary_heap_alloc because we don't want to allocate
+             * on the transient heap. */
+            VALUE *ptr = ALLOC_N(VALUE, capa);
+            ARY_SET_PTR(shared, ptr);
+            ary_memcpy(shared, 0, len, RARRAY_PTR(ary));
+
+            FL_UNSET_EMBED(ary);
+            ARY_SET_HEAP_LEN(ary, len);
+            ARY_SET_PTR(ary, ptr);
+        }
+        else {
+            ARY_SET_PTR(shared, RARRAY_PTR(ary));
+        }
 
-	ARY_SET_LEN((VALUE)shared, capa);
-	ARY_SET_PTR((VALUE)shared, RARRAY_CONST_PTR(ary));
-	ary_mem_clear((VALUE)shared, len, capa - len);
-	FL_SET_SHARED_ROOT(shared);
-	ARY_SET_SHARED_NUM((VALUE)shared, 1);
-	FL_SET_SHARED(ary);
-	ARY_SET_SHARED(ary, (VALUE)shared);
-	OBJ_FREEZE(shared);
-	return (VALUE)shared;
+        ARY_SET_LEN(shared, capa);
+        ary_mem_clear(shared, len, capa - len);
+        ARY_SET_SHARED_ROOT_REFCNT(shared, 1);
+        FL_SET_SHARED(ary);
+        RB_DEBUG_COUNTER_INC(obj_ary_shared_create);
+        ARY_SET_SHARED(ary, shared);
+
+        ary_verify(shared);
+        ary_verify(ary);
+
+        return shared;
     }
 }
 
@@ -608,9 +1099,11 @@ ary_make_substitution(VALUE ary)
 {
     long len = RARRAY_LEN(ary);
 
-    if (len <= RARRAY_EMBED_LEN_MAX) {
-	VALUE subst = rb_ary_new2(len);
-	ary_memcpy(subst, 0, len, RARRAY_CONST_PTR(ary));
+    if (ary_embeddable_p(len)) {
+        VALUE subst = rb_ary_new_capa(len);
+        assert(ARY_EMBED_P(subst));
+
+        ary_memcpy(subst, 0, len, RARRAY_CONST_PTR_TRANSIENT(ary));
         ARY_SET_EMBED_LEN(subst, len);
         return subst;
     }
@@ -625,35 +1118,43 @@ rb_assoc_new(VALUE car, VALUE cdr)
     return rb_ary_new3(2, car, cdr);
 }
 
-static VALUE
-to_ary(VALUE ary)
+VALUE
+rb_to_array_type(VALUE ary)
 {
-    return rb_convert_type(ary, T_ARRAY, "Array", "to_ary");
+    return rb_convert_type_with_id(ary, T_ARRAY, "Array", idTo_ary);
 }
+#define to_ary rb_to_array_type
 
 VALUE
 rb_check_array_type(VALUE ary)
 {
-    return rb_check_convert_type(ary, T_ARRAY, "Array", "to_ary");
+    return rb_check_convert_type_with_id(ary, T_ARRAY, "Array", idTo_ary);
+}
+
+MJIT_FUNC_EXPORTED VALUE
+rb_check_to_array(VALUE ary)
+{
+    return rb_check_convert_type_with_id(ary, T_ARRAY, "Array", idTo_a);
+}
+
+VALUE
+rb_to_array(VALUE ary)
+{
+    return rb_convert_type_with_id(ary, T_ARRAY, "Array", idTo_a);
 }
 
 /*
  *  call-seq:
- *     Array.try_convert(obj) -> array or nil
+ *    Array.try_convert(object) -> object, new_array, or nil
  *
- *  Tries to convert +obj+ into an array, using +to_ary+ method.  Returns the
- *  converted array or +nil+ if +obj+ cannot be converted for any reason.
- *  This method can be used to check if an argument is an array.
+ *  If +object+ is an \Array object, returns +object+.
  *
- *     Array.try_convert([1])   #=> [1]
- *     Array.try_convert("1")   #=> nil
+ *  Otherwise if +object+ responds to <tt>:to_ary</tt>,
+ *  calls <tt>object.to_ary</tt> and returns the result.
  *
- *     if tmp = Array.try_convert(arg)
- *       # the argument is an array
- *     elsif tmp = String.try_convert(arg)
- *       # the argument is a string
- *     end
+ *  Returns +nil+ if +object+ does not respond to <tt>:to_ary</tt>
  *
+ *  Raises an exception unless <tt>object.to_ary</tt> returns an \Array object.
  */
 
 static VALUE
@@ -662,60 +1163,76 @@ rb_ary_s_try_convert(VALUE dummy, VALUE ary)
     return rb_check_array_type(ary);
 }
 
+/* :nodoc: */
+static VALUE
+rb_ary_s_new(int argc, VALUE *argv, VALUE klass)
+{
+    VALUE ary;
+
+    if (klass == rb_cArray) {
+        long size = 0;
+        if (argc > 0 && FIXNUM_P(argv[0])) {
+            size = FIX2LONG(argv[0]);
+            if (size < 0) size = 0;
+        }
+
+        ary = ary_new(klass, size);
+
+        rb_obj_call_init_kw(ary, argc, argv, RB_PASS_CALLED_KEYWORDS);
+    }
+    else {
+        ary = rb_class_new_instance_pass_kw(argc, argv, klass);
+    }
+
+    return ary;
+}
+
 /*
  *  call-seq:
- *     Array.new(size=0, default=nil)
- *     Array.new(array)
- *     Array.new(size) {|index| block }
- *
- *  Returns a new array.
- *
- *  In the first form, if no arguments are sent, the new array will be empty.
- *  When a +size+ and an optional +default+ are sent, an array is created with
- *  +size+ copies of +default+.  Take notice that all elements will reference the
- *  same object +default+.
- *
- *  The second form creates a copy of the array passed as a parameter (the
- *  array is generated by calling to_ary on the parameter).
- *
- *    first_array = ["Matz", "Guido"]
+ *    Array.new -> new_empty_array
+ *    Array.new(array) -> new_array
+ *    Array.new(size) -> new_array
+ *    Array.new(size, default_value) -> new_array
+ *    Array.new(size) {|index| ... } -> new_array
  *
- *    second_array = Array.new(first_array) #=> ["Matz", "Guido"]
+ *  Returns a new \Array.
  *
- *    first_array.equal? second_array       #=> false
+ *  With no block and no arguments, returns a new empty \Array object.
  *
- *  In the last form, an array of the given size is created.  Each element in
- *  this array is created by passing the element's index to the given block
- *  and storing the return value.
+ *  With no block and a single \Array argument +array+,
+ *  returns a new \Array formed from +array+:
  *
- *    Array.new(3){ |index| index ** 2 }
- *    # => [0, 1, 4]
+ *    a = Array.new([:foo, 'bar', 2])
+ *    a.class # => Array
+ *    a # => [:foo, "bar", 2]
  *
- *  == Common gotchas
+ *  With no block and a single \Integer argument +size+,
+ *  returns a new \Array of the given size
+ *  whose elements are all +nil+:
  *
- *  When sending the second parameter, the same object will be used as the
- *  value for all the array elements:
+ *    a = Array.new(3)
+ *    a # => [nil, nil, nil]
  *
- *     a = Array.new(2, Hash.new)
- *     # => [{}, {}]
+ *  With no block and arguments +size+ and +default_value+,
+ *  returns an \Array of the given size;
+ *  each element is that same +default_value+:
  *
- *     a[0]['cat'] = 'feline'
- *     a # => [{"cat"=>"feline"}, {"cat"=>"feline"}]
+ *    a = Array.new(3, 'x')
+ *    a # => ['x', 'x', 'x']
  *
- *     a[1]['cat'] = 'Felix'
- *     a # => [{"cat"=>"Felix"}, {"cat"=>"Felix"}]
+ *  With a block and argument +size+,
+ *  returns an \Array of the given size;
+ *  the block is called with each successive integer +index+;
+ *  the element for that +index+ is the return value from the block:
  *
- *  Since all the Array elements store the same hash, changes to one of them
- *  will affect them all.
+ *    a = Array.new(3) {|index| "Element #{index}" }
+ *    a # => ["Element 0", "Element 1", "Element 2"]
  *
- *  If multiple copies are what you want, you should use the block
- *  version which uses the result of that block each time an element
- *  of the array needs to be initialized:
- *
- *     a = Array.new(2) { Hash.new }
- *     a[0]['cat'] = 'feline'
- *     a # => [{"cat"=>"feline"}, {}]
+ *  Raises ArgumentError if +size+ is negative.
  *
+ *  With a block and no argument,
+ *  or a single argument +0+,
+ *  ignores the block and returns a new empty \Array.
  */
 
 static VALUE
@@ -726,51 +1243,48 @@ rb_ary_initialize(int argc, VALUE *argv, VALUE ary)
 
     rb_ary_modify(ary);
     if (argc == 0) {
-	if (ARY_OWNS_HEAP_P(ary) && RARRAY_CONST_PTR(ary) != 0) {
-	    ruby_sized_xfree((void *)RARRAY_CONST_PTR(ary), ARY_HEAP_SIZE(ary));
-	}
-        rb_ary_unshare_safe(ary);
-        FL_SET_EMBED(ary);
-	ARY_SET_EMBED_LEN(ary, 0);
-	if (rb_block_given_p()) {
-	    rb_warning("given block not used");
-	}
-	return ary;
+        rb_ary_reset(ary);
+        assert(ARY_EMBED_P(ary));
+        assert(ARY_EMBED_LEN(ary) == 0);
+        if (rb_block_given_p()) {
+            rb_warning("given block not used");
+        }
+        return ary;
     }
     rb_scan_args(argc, argv, "02", &size, &val);
     if (argc == 1 && !FIXNUM_P(size)) {
-	val = rb_check_array_type(size);
-	if (!NIL_P(val)) {
-	    rb_ary_replace(ary, val);
-	    return ary;
-	}
+        val = rb_check_array_type(size);
+        if (!NIL_P(val)) {
+            rb_ary_replace(ary, val);
+            return ary;
+        }
     }
 
     len = NUM2LONG(size);
     /* NUM2LONG() may call size.to_int, ary can be frozen, modified, etc */
     if (len < 0) {
-	rb_raise(rb_eArgError, "negative array size");
+        rb_raise(rb_eArgError, "negative array size");
     }
     if (len > ARY_MAX_SIZE) {
-	rb_raise(rb_eArgError, "array size too big");
+        rb_raise(rb_eArgError, "array size too big");
     }
     /* recheck after argument conversion */
     rb_ary_modify(ary);
     ary_resize_capa(ary, len);
     if (rb_block_given_p()) {
-	long i;
+        long i;
 
-	if (argc == 2) {
-	    rb_warn("block supersedes default value argument");
-	}
-	for (i=0; i<len; i++) {
-	    rb_ary_store(ary, i, rb_yield(LONG2NUM(i)));
-	    ARY_SET_LEN(ary, i + 1);
-	}
+        if (argc == 2) {
+            rb_warn("block supersedes default value argument");
+        }
+        for (i=0; i<len; i++) {
+            rb_ary_store(ary, i, rb_yield(LONG2NUM(i)));
+            ARY_SET_LEN(ary, i + 1);
+        }
     }
     else {
-	ary_memfill(ary, 0, len, val);
-	ARY_SET_LEN(ary, len);
+        ary_memfill(ary, 0, len, val);
+        ARY_SET_LEN(ary, len);
     }
     return ary;
 }
@@ -778,7 +1292,7 @@ rb_ary_initialize(int argc, VALUE *argv, VALUE ary)
 /*
  * Returns a new array populated with the given objects.
  *
- *   Array.[]( 1, 'a', /^A/ ) # => [1, "a", /^A/]
+ *   Array.[]( 1, 'a', /^A/)  # => [1, "a", /^A/]
  *   Array[ 1, 'a', /^A/ ]    # => [1, "a", /^A/]
  *   [ 1, 'a', /^A/ ]         # => [1, "a", /^A/]
  */
@@ -801,26 +1315,26 @@ rb_ary_store(VALUE ary, long idx, VALUE val)
     long len = RARRAY_LEN(ary);
 
     if (idx < 0) {
-	idx += len;
-	if (idx < 0) {
-	    rb_raise(rb_eIndexError, "index %ld too small for array; minimum: %ld",
-		     idx - len, -len);
-	}
+        idx += len;
+        if (idx < 0) {
+            rb_raise(rb_eIndexError, "index %ld too small for array; minimum: %ld",
+                     idx - len, -len);
+        }
     }
     else if (idx >= ARY_MAX_SIZE) {
-	rb_raise(rb_eIndexError, "index %ld too big", idx);
+        rb_raise(rb_eIndexError, "index %ld too big", idx);
     }
 
     rb_ary_modify(ary);
     if (idx >= ARY_CAPA(ary)) {
-	ary_double_capa(ary, idx);
+        ary_double_capa(ary, idx);
     }
     if (idx > len) {
-	ary_mem_clear(ary, len, idx - len + 1);
+        ary_mem_clear(ary, len, idx - len + 1);
     }
 
     if (idx >= len) {
-	ARY_SET_LEN(ary, idx + 1);
+        ARY_SET_LEN(ary, idx + 1);
     }
     ARY_SET(ary, idx, val);
 }
@@ -832,31 +1346,87 @@ ary_make_partial(VALUE ary, VALUE klass, long offset, long len)
     assert(len >= 0);
     assert(offset+len <= RARRAY_LEN(ary));
 
-    if (len <= RARRAY_EMBED_LEN_MAX) {
-        VALUE result = ary_alloc(klass);
-	ary_memcpy(result, 0, len, RARRAY_CONST_PTR(ary) + offset);
+    const size_t rarray_embed_capa_max = (sizeof(struct RArray) - offsetof(struct RArray, as.ary)) / sizeof(VALUE);
+
+    if ((size_t)len <= rarray_embed_capa_max && ary_embeddable_p(len)) {
+        VALUE result = ary_alloc_embed(klass, len);
+        ary_memcpy(result, 0, len, RARRAY_CONST_PTR_TRANSIENT(ary) + offset);
         ARY_SET_EMBED_LEN(result, len);
         return result;
     }
     else {
-        VALUE shared, result = ary_alloc(klass);
-        FL_UNSET_EMBED(result);
+        VALUE shared = ary_make_shared(ary);
 
-        shared = ary_make_shared(ary);
-        ARY_SET_PTR(result, RARRAY_CONST_PTR(ary));
+        VALUE result = ary_alloc_heap(klass);
+        assert(!ARY_EMBED_P(result));
+
+        ARY_SET_PTR(result, RARRAY_CONST_PTR_TRANSIENT(ary));
         ARY_SET_LEN(result, RARRAY_LEN(ary));
         rb_ary_set_shared(result, shared);
 
         ARY_INCREASE_PTR(result, offset);
         ARY_SET_LEN(result, len);
+
+        ary_verify(shared);
+        ary_verify(result);
+        return result;
+    }
+}
+
+static VALUE
+ary_make_partial_step(VALUE ary, VALUE klass, long offset, long len, long step)
+{
+    assert(offset >= 0);
+    assert(len >= 0);
+    assert(offset+len <= RARRAY_LEN(ary));
+    assert(step != 0);
+
+    const VALUE *values = RARRAY_CONST_PTR_TRANSIENT(ary);
+    const long orig_len = len;
+
+    if (step > 0 && step >= len) {
+        VALUE result = ary_new(klass, 1);
+        VALUE *ptr = (VALUE *)ARY_EMBED_PTR(result);
+        RB_OBJ_WRITE(result, ptr, values[offset]);
+        ARY_SET_EMBED_LEN(result, 1);
         return result;
     }
+    else if (step < 0 && step < -len) {
+        step = -len;
+    }
+
+    long ustep = (step < 0) ? -step : step;
+    len = roomof(len, ustep);
+
+    long i;
+    long j = offset + ((step > 0) ? 0 : (orig_len - 1));
+
+    VALUE result = ary_new(klass, len);
+    if (ARY_EMBED_P(result)) {
+        VALUE *ptr = (VALUE *)ARY_EMBED_PTR(result);
+        for (i = 0; i < len; ++i) {
+            RB_OBJ_WRITE(result, ptr+i, values[j]);
+            j += step;
+        }
+        ARY_SET_EMBED_LEN(result, len);
+    }
+    else {
+        RARRAY_PTR_USE_TRANSIENT(result, ptr, {
+            for (i = 0; i < len; ++i) {
+                RB_OBJ_WRITE(result, ptr+i, values[j]);
+                j += step;
+            }
+        });
+        ARY_SET_LEN(result, len);
+    }
+
+    return result;
 }
 
 static VALUE
 ary_make_shared_copy(VALUE ary)
 {
-    return ary_make_partial(ary, rb_obj_class(ary), 0, RARRAY_LEN(ary));
+    return ary_make_partial(ary, rb_cArray, 0, RARRAY_LEN(ary));
 }
 
 enum ary_take_pos_flags
@@ -868,48 +1438,57 @@ enum ary_take_pos_flags
 static VALUE
 ary_take_first_or_last(int argc, const VALUE *argv, VALUE ary, enum ary_take_pos_flags last)
 {
-    VALUE nv;
     long n;
     long len;
     long offset = 0;
 
-    rb_scan_args(argc, argv, "1", &nv);
-    n = NUM2LONG(nv);
+    argc = rb_check_arity(argc, 0, 1);
+    /* the case optional argument is omitted should be handled in
+     * callers of this function.  if another arity case is added,
+     * this arity check needs to rewrite. */
+    RUBY_ASSERT_ALWAYS(argc == 1);
+
+    n = NUM2LONG(argv[0]);
     len = RARRAY_LEN(ary);
     if (n > len) {
-	n = len;
+        n = len;
     }
     else if (n < 0) {
-	rb_raise(rb_eArgError, "negative array size");
+        rb_raise(rb_eArgError, "negative array size");
     }
     if (last) {
-	offset = len - n;
+        offset = len - n;
     }
     return ary_make_partial(ary, rb_cArray, offset, n);
 }
 
 /*
  *  call-seq:
- *     ary << obj            -> ary
+ *    array << object -> self
+ *
+ *  Appends +object+ to +self+; returns +self+:
  *
- *  Append---Pushes the given object on to the end of this array. This
- *  expression returns the array itself, so several appends
- *  may be chained together.
+ *    a = [:foo, 'bar', 2]
+ *    a << :baz # => [:foo, "bar", 2, :baz]
  *
- *     [ 1, 2 ] << "c" << "d" << [ 3, 4 ]
- *             #=>  [ 1, 2, "c", "d", [ 3, 4 ] ]
+ *  Appends +object+ as one element, even if it is another \Array:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a1 = a << [3, 4]
+ *    a1 # => [:foo, "bar", 2, [3, 4]]
  *
  */
 
 VALUE
 rb_ary_push(VALUE ary, VALUE item)
 {
-    long idx = RARRAY_LEN(ary);
+    long idx = RARRAY_LEN((ary_verify(ary), ary));
     VALUE target_ary = ary_ensure_room_for_push(ary, 1);
-    RARRAY_PTR_USE(ary, ptr, {
-	RB_OBJ_WRITE(target_ary, &ptr[idx], item);
+    RARRAY_PTR_USE_TRANSIENT(ary, ptr, {
+        RB_OBJ_WRITE(target_ary, &ptr[idx], item);
     });
     ARY_SET_LEN(ary, idx + 1);
+    ary_verify(ary);
     return ary;
 }
 
@@ -925,18 +1504,24 @@ rb_ary_cat(VALUE ary, const VALUE *argv, long len)
 
 /*
  *  call-seq:
- *     ary.push(obj, ... )   -> ary
- *
- *  Append --- Pushes the given object(s) on to the end of this array. This
- *  expression returns the array itself, so several appends
- *  may be chained together. See also Array#pop for the opposite
- *  effect.
- *
- *     a = [ "a", "b", "c" ]
- *     a.push("d", "e", "f")
- *             #=> ["a", "b", "c", "d", "e", "f"]
- *     [1, 2, 3].push(4).push(5)
- *             #=> [1, 2, 3, 4, 5]
+ *    array.push(*objects) -> self
+ *
+ *  Appends trailing elements.
+ *
+ *  Appends each argument in +objects+ to +self+;  returns +self+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.push(:baz, :bat) # => [:foo, "bar", 2, :baz, :bat]
+ *
+ *  Appends each argument as one element, even if it is another \Array:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a1 = a.push([:baz, :bat], [:bam, :bad])
+ *    a1 # => [:foo, "bar", 2, [:baz, :bat], [:bam, :bad]]
+ *
+ *  Array#append is an alias for Array#push.
+ *
+ *  Related: #pop, #shift, #unshift.
  */
 
 static VALUE
@@ -953,32 +1538,46 @@ rb_ary_pop(VALUE ary)
     n = RARRAY_LEN(ary);
     if (n == 0) return Qnil;
     if (ARY_OWNS_HEAP_P(ary) &&
-	n * 3 < ARY_CAPA(ary) &&
-	ARY_CAPA(ary) > ARY_DEFAULT_SIZE)
+        n * 3 < ARY_CAPA(ary) &&
+        ARY_CAPA(ary) > ARY_DEFAULT_SIZE)
     {
-	ary_resize_capa(ary, n * 2);
+        ary_resize_capa(ary, n * 2);
     }
     --n;
     ARY_SET_LEN(ary, n);
+    ary_verify(ary);
     return RARRAY_AREF(ary, n);
 }
 
 /*
  *  call-seq:
- *     ary.pop    -> obj or nil
- *     ary.pop(n) -> new_ary
+ *    array.pop -> object or nil
+ *    array.pop(n) -> new_array
  *
- *  Removes the last element from +self+ and returns it, or
- *  +nil+ if the array is empty.
+ *  Removes and returns trailing elements.
  *
- *  If a number +n+ is given, returns an array of the last +n+ elements
- *  (or less) just like <code>array.slice!(-n, n)</code> does. See also
- *  Array#push for the opposite effect.
+ *  When no argument is given and +self+ is not empty,
+ *  removes and returns the last element:
  *
- *     a = [ "a", "b", "c", "d" ]
- *     a.pop     #=> "d"
- *     a.pop(2)  #=> ["b", "c"]
- *     a         #=> ["a"]
+ *    a = [:foo, 'bar', 2]
+ *    a.pop # => 2
+ *    a # => [:foo, "bar"]
+ *
+ *  Returns +nil+ if the array is empty.
+ *
+ *  When a non-negative \Integer argument +n+ is given and is in range,
+ *
+ *  removes and returns the last +n+ elements in a new \Array:
+ *    a = [:foo, 'bar', 2]
+ *    a.pop(2) # => ["bar", 2]
+ *
+ *  If +n+ is positive and out of range,
+ *  removes and returns all elements:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.pop(50) # => [:foo, "bar", 2]
+ *
+ *  Related: #push, #shift, #unshift.
  */
 
 static VALUE
@@ -987,12 +1586,13 @@ rb_ary_pop_m(int argc, VALUE *argv, VALUE ary)
     VALUE result;
 
     if (argc == 0) {
-	return rb_ary_pop(ary);
+        return rb_ary_pop(ary);
     }
 
     rb_ary_modify_check(ary);
     result = ary_take_first_or_last(argc, argv, ary, ARY_TAKE_LAST);
     ARY_INCREASE_LEN(ary, -RARRAY_LEN(result));
+    ary_verify(ary);
     return result;
 }
 
@@ -1002,52 +1602,49 @@ rb_ary_shift(VALUE ary)
     VALUE top;
     long len = RARRAY_LEN(ary);
 
-    rb_ary_modify_check(ary);
-    if (len == 0) return Qnil;
+    if (len == 0) {
+        rb_ary_modify_check(ary);
+        return Qnil;
+    }
+
     top = RARRAY_AREF(ary, 0);
-    if (!ARY_SHARED_P(ary)) {
-	if (len < ARY_DEFAULT_SIZE) {
-	    RARRAY_PTR_USE(ary, ptr, {
-		MEMMOVE(ptr, ptr+1, VALUE, len-1);
-	    }); /* WB: no new reference */
-            ARY_INCREASE_LEN(ary, -1);
-	    return top;
-	}
-        assert(!ARY_EMBED_P(ary)); /* ARY_EMBED_LEN_MAX < ARY_DEFAULT_SIZE */
-
-	ARY_SET(ary, 0, Qnil);
-	ary_make_shared(ary);
-    }
-    else if (ARY_SHARED_OCCUPIED(ARY_SHARED(ary))) {
-	RARRAY_PTR_USE(ary, ptr, ptr[0] = Qnil);
-    }
-    ARY_INCREASE_PTR(ary, 1);		/* shift ptr */
-    ARY_INCREASE_LEN(ary, -1);
+
+    rb_ary_behead(ary, 1);
 
     return top;
 }
 
 /*
  *  call-seq:
- *     ary.shift    -> obj or nil
- *     ary.shift(n) -> new_ary
+ *     array.shift -> object or nil
+ *     array.shift(n) -> new_array
+ *
+ *  Removes and returns leading elements.
+ *
+ *  When no argument is given, removes and returns the first element:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.shift # => :foo
+ *    a # => ['bar', 2]
+ *
+ *  Returns +nil+ if +self+ is empty.
+ *
+ *  When positive \Integer argument +n+ is given, removes the first +n+ elements;
+ *  returns those elements in a new \Array:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.shift(2) # => [:foo, 'bar']
+ *    a # => [2]
  *
- *  Removes the first element of +self+ and returns it (shifting all
- *  other elements down by one). Returns +nil+ if the array
- *  is empty.
+ *  If +n+ is as large as or larger than <tt>self.length</tt>,
+ *  removes all elements; returns those elements in a new \Array:
  *
- *  If a number +n+ is given, returns an array of the first +n+ elements
- *  (or less) just like <code>array.slice!(0, n)</code> does. With +ary+
- *  containing only the remainder elements, not including what was shifted to
- *  +new_ary+. See also Array#unshift for the opposite effect.
+ *    a = [:foo, 'bar', 2]
+ *    a.shift(3) # => [:foo, 'bar', 2]
  *
- *     args = [ "-m", "-q", "filename" ]
- *     args.shift     #=> "-m"
- *     args           #=> ["-q", "filename"]
+ *  If +n+ is zero, returns a new empty \Array; +self+ is unmodified.
  *
- *     args = [ "-m", "-q", "filename" ]
- *     args.shift(2)  #=> ["-m", "-q"]
- *     args           #=> ["filename"]
+ *  Related: #push, #pop, #unshift.
  */
 
 static VALUE
@@ -1057,104 +1654,147 @@ rb_ary_shift_m(int argc, VALUE *argv, VALUE ary)
     long n;
 
     if (argc == 0) {
-	return rb_ary_shift(ary);
+        return rb_ary_shift(ary);
     }
 
     rb_ary_modify_check(ary);
     result = ary_take_first_or_last(argc, argv, ary, ARY_TAKE_FIRST);
     n = RARRAY_LEN(result);
-    if (ARY_SHARED_P(ary)) {
-	if (ARY_SHARED_OCCUPIED(ARY_SHARED(ary))) {
-	  setup_occupied_shared:
-	    ary_mem_clear(ary, 0, n);
-	}
-        ARY_INCREASE_PTR(ary, n);
+    rb_ary_behead(ary,n);
+
+    return result;
+}
+
+MJIT_FUNC_EXPORTED VALUE
+rb_ary_behead(VALUE ary, long n)
+{
+    if (n <= 0) {
+        return ary;
     }
-    else {
-	if (RARRAY_LEN(ary) < ARY_DEFAULT_SIZE) {
-	    RARRAY_PTR_USE(ary, ptr, {
-		MEMMOVE(ptr, ptr+n, VALUE, RARRAY_LEN(ary)-n);
-	    }); /* WB: no new reference */
-	}
-	else {
-	    ary_make_shared(ary);
-	    goto setup_occupied_shared;
-	}
+
+    rb_ary_modify_check(ary);
+
+    if (!ARY_SHARED_P(ary)) {
+        if (ARY_EMBED_P(ary) || RARRAY_LEN(ary) < ARY_DEFAULT_SIZE) {
+            RARRAY_PTR_USE_TRANSIENT(ary, ptr, {
+                MEMMOVE(ptr, ptr + n, VALUE, RARRAY_LEN(ary) - n);
+            }); /* WB: no new reference */
+            ARY_INCREASE_LEN(ary, -n);
+            ary_verify(ary);
+            return ary;
+        }
+
+        ary_mem_clear(ary, 0, n);
+        ary_make_shared(ary);
+    }
+    else if (ARY_SHARED_ROOT_OCCUPIED(ARY_SHARED_ROOT(ary))) {
+        ary_mem_clear(ary, 0, n);
     }
+
+    ARY_INCREASE_PTR(ary, n);
     ARY_INCREASE_LEN(ary, -n);
+    ary_verify(ary);
 
-    return result;
+    return ary;
 }
 
 static VALUE
-ary_ensure_room_for_unshift(VALUE ary, int argc)
+make_room_for_unshift(VALUE ary, const VALUE *head, VALUE *sharedp, int argc, long capa, long len)
+{
+    if (head - sharedp < argc) {
+        long room = capa - len - argc;
+
+        room -= room >> 4;
+        MEMMOVE((VALUE *)sharedp + argc + room, head, VALUE, len);
+        head = sharedp + argc + room;
+    }
+    ARY_SET_PTR(ary, head - argc);
+    assert(ARY_SHARED_ROOT_OCCUPIED(ARY_SHARED_ROOT(ary)));
+
+    ary_verify(ary);
+    return ARY_SHARED_ROOT(ary);
+}
+
+static VALUE
+ary_modify_for_unshift(VALUE ary, int argc)
 {
     long len = RARRAY_LEN(ary);
     long new_len = len + argc;
     long capa;
     const VALUE *head, *sharedp;
 
-    if (len > ARY_MAX_SIZE - argc) {
-	rb_raise(rb_eIndexError, "index %ld too big", new_len);
-    }
-
-    if (ARY_SHARED_P(ary)) {
-	VALUE shared = ARY_SHARED(ary);
-	capa = RARRAY_LEN(shared);
-	if (ARY_SHARED_OCCUPIED(shared) && capa > new_len) {
-	    head = RARRAY_CONST_PTR(ary);
-	    sharedp = RARRAY_CONST_PTR(shared);
-	    goto makeroom_if_need;
-	}
-    }
-
     rb_ary_modify(ary);
     capa = ARY_CAPA(ary);
     if (capa - (capa >> 6) <= new_len) {
-	ary_double_capa(ary, new_len);
+        ary_double_capa(ary, new_len);
     }
 
     /* use shared array for big "queues" */
-    if (new_len > ARY_DEFAULT_SIZE * 4) {
-	/* make a room for unshifted items */
-	capa = ARY_CAPA(ary);
-	ary_make_shared(ary);
-
-	head = sharedp = RARRAY_CONST_PTR(ary);
-	goto makeroom;
-      makeroom_if_need:
-	if (head - sharedp < argc) {
-	    long room;
-	  makeroom:
-	    room = capa - new_len;
-	    room -= room >> 4;
-	    MEMMOVE((VALUE *)sharedp + argc + room, head, VALUE, len);
-	    head = sharedp + argc + room;
-	}
-	ARY_SET_PTR(ary, head - argc);
-	assert(ARY_SHARED_OCCUPIED(ARY_SHARED(ary)));
-	return ARY_SHARED(ary);
+    if (new_len > ARY_DEFAULT_SIZE * 4 && !ARY_EMBED_P(ary)) {
+        ary_verify(ary);
+
+        /* make a room for unshifted items */
+        capa = ARY_CAPA(ary);
+        ary_make_shared(ary);
+
+        head = sharedp = RARRAY_CONST_PTR_TRANSIENT(ary);
+        return make_room_for_unshift(ary, head, (void *)sharedp, argc, capa, len);
+    }
+    else {
+        /* sliding items */
+        RARRAY_PTR_USE_TRANSIENT(ary, ptr, {
+            MEMMOVE(ptr + argc, ptr, VALUE, len);
+        });
+
+        ary_verify(ary);
+        return ary;
+    }
+}
+
+static VALUE
+ary_ensure_room_for_unshift(VALUE ary, int argc)
+{
+    long len = RARRAY_LEN(ary);
+    long new_len = len + argc;
+
+    if (len > ARY_MAX_SIZE - argc) {
+        rb_raise(rb_eIndexError, "index %ld too big", new_len);
+    }
+    else if (! ARY_SHARED_P(ary)) {
+        return ary_modify_for_unshift(ary, argc);
     }
     else {
-	/* sliding items */
-	RARRAY_PTR_USE(ary, ptr, {
-	    MEMMOVE(ptr + argc, ptr, VALUE, len);
-	});
+        VALUE shared_root = ARY_SHARED_ROOT(ary);
+        long capa = RARRAY_LEN(shared_root);
 
-	return ary;
+        if (! ARY_SHARED_ROOT_OCCUPIED(shared_root)) {
+            return ary_modify_for_unshift(ary, argc);
+        }
+        else if (new_len > capa) {
+            return ary_modify_for_unshift(ary, argc);
+        }
+        else {
+            const VALUE * head = RARRAY_CONST_PTR_TRANSIENT(ary);
+            void *sharedp = (void *)RARRAY_CONST_PTR_TRANSIENT(shared_root);
+
+            rb_ary_modify_check(ary);
+            return make_room_for_unshift(ary, head, sharedp, argc, capa, len);
+        }
     }
 }
 
 /*
  *  call-seq:
- *     ary.unshift(obj, ...)  -> ary
+ *    array.unshift(*objects) -> self
  *
- *  Prepends objects to the front of +self+, moving other elements upwards.
- *  See also Array#shift for the opposite effect.
+ *  Prepends the given +objects+ to +self+:
  *
- *     a = [ "b", "c", "d" ]
- *     a.unshift("a")   #=> ["a", "b", "c", "d"]
- *     a.unshift(1, 2)  #=> [ 1, 2, "a", "b", "c", "d"]
+ *    a = [:foo, 'bar', 2]
+ *    a.unshift(:bam, :bat) # => [:bam, :bat, :foo, "bar", 2]
+ *
+ *  Array#prepend is an alias for Array#unshift.
+ *
+ *  Related: #push, #pop, #shift.
  */
 
 static VALUE
@@ -1164,8 +1804,8 @@ rb_ary_unshift_m(int argc, VALUE *argv, VALUE ary)
     VALUE target_ary;
 
     if (argc == 0) {
-	rb_ary_modify_check(ary);
-	return ary;
+        rb_ary_modify_check(ary);
+        return ary;
     }
 
     target_ary = ary_ensure_room_for_unshift(ary, argc);
@@ -1187,7 +1827,7 @@ rb_ary_elt(VALUE ary, long offset)
     long len = RARRAY_LEN(ary);
     if (len == 0) return Qnil;
     if (offset < 0 || len <= offset) {
-	return Qnil;
+        return Qnil;
     }
     return RARRAY_AREF(ary, offset);
 }
@@ -1195,21 +1835,11 @@ rb_ary_elt(VALUE ary, long offset)
 VALUE
 rb_ary_entry(VALUE ary, long offset)
 {
-    long len = RARRAY_LEN(ary);
-    const VALUE *ptr = RARRAY_CONST_PTR(ary);
-    if (len == 0) return Qnil;
-    if (offset < 0) {
-        offset += len;
-        if (offset < 0) return Qnil;
-    }
-    else if (len <= offset) {
-        return Qnil;
-    }
-    return ptr[offset];
+    return rb_ary_entry_internal(ary, offset);
 }
 
 VALUE
-rb_ary_subseq(VALUE ary, long beg, long len)
+rb_ary_subseq_step(VALUE ary, long beg, long len, long step)
 {
     VALUE klass;
     long alen = RARRAY_LEN(ary);
@@ -1218,95 +1848,183 @@ rb_ary_subseq(VALUE ary, long beg, long len)
     if (beg < 0 || len < 0) return Qnil;
 
     if (alen < len || alen < beg + len) {
-	len = alen - beg;
+        len = alen - beg;
     }
-    klass = rb_obj_class(ary);
+    klass = rb_cArray;
     if (len == 0) return ary_new(klass, 0);
+    if (step == 0)
+        rb_raise(rb_eArgError, "slice step cannot be zero");
+    if (step == 1)
+        return ary_make_partial(ary, klass, beg, len);
+    else
+        return ary_make_partial_step(ary, klass, beg, len, step);
+}
 
-    return ary_make_partial(ary, klass, beg, len);
+VALUE
+rb_ary_subseq(VALUE ary, long beg, long len)
+{
+    return rb_ary_subseq_step(ary, beg, len, 1);
 }
 
+static VALUE rb_ary_aref2(VALUE ary, VALUE b, VALUE e);
+
 /*
  *  call-seq:
- *     ary[index]                -> obj     or nil
- *     ary[start, length]        -> new_ary or nil
- *     ary[range]                -> new_ary or nil
- *     ary.slice(index)          -> obj     or nil
- *     ary.slice(start, length)  -> new_ary or nil
- *     ary.slice(range)          -> new_ary or nil
- *
- *  Element Reference --- Returns the element at +index+, or returns a
- *  subarray starting at the +start+ index and continuing for +length+
- *  elements, or returns a subarray specified by +range+ of indices.
- *
- *  Negative indices count backward from the end of the array (-1 is the last
- *  element).  For +start+ and +range+ cases the starting index is just before
- *  an element.  Additionally, an empty array is returned when the starting
- *  index for an element range is at the end of the array.
- *
- *  Returns +nil+ if the index (or starting index) are out of range.
- *
- *     a = [ "a", "b", "c", "d", "e" ]
- *     a[2] +  a[0] + a[1]    #=> "cab"
- *     a[6]                   #=> nil
- *     a[1, 2]                #=> [ "b", "c" ]
- *     a[1..3]                #=> [ "b", "c", "d" ]
- *     a[4..7]                #=> [ "e" ]
- *     a[6..10]               #=> nil
- *     a[-3, 3]               #=> [ "c", "d", "e" ]
- *     # special cases
- *     a[5]                   #=> nil
- *     a[6, 1]                #=> nil
- *     a[5, 1]                #=> []
- *     a[5..10]               #=> []
+ *    array[index] -> object or nil
+ *    array[start, length] -> object or nil
+ *    array[range] -> object or nil
+ *    array[aseq] -> object or nil
+ *    array.slice(index) -> object or nil
+ *    array.slice(start, length) -> object or nil
+ *    array.slice(range) -> object or nil
+ *    array.slice(aseq) -> object or nil
+ *
+ *  Returns elements from +self+; does not modify +self+.
+ *
+ *  When a single \Integer argument +index+ is given, returns the element at offset +index+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[0] # => :foo
+ *    a[2] # => 2
+ *    a # => [:foo, "bar", 2]
+ *
+ *  If +index+ is negative, counts relative to the end of +self+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[-1] # => 2
+ *    a[-2] # => "bar"
+ *
+ *  If +index+ is out of range, returns +nil+.
+ *
+ *  When two \Integer arguments +start+ and +length+ are given,
+ *  returns a new \Array of size +length+ containing successive elements beginning at offset +start+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[0, 2] # => [:foo, "bar"]
+ *    a[1, 2] # => ["bar", 2]
+ *
+ *  If <tt>start + length</tt> is greater than <tt>self.length</tt>,
+ *  returns all elements from offset +start+ to the end:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[0, 4] # => [:foo, "bar", 2]
+ *    a[1, 3] # => ["bar", 2]
+ *    a[2, 2] # => [2]
+ *
+ *  If <tt>start == self.size</tt> and <tt>length >= 0</tt>,
+ *  returns a new empty \Array.
+ *
+ *  If +length+ is negative, returns +nil+.
+ *
+ *  When a single \Range argument +range+ is given,
+ *  treats <tt>range.min</tt> as +start+ above
+ *  and <tt>range.size</tt> as +length+ above:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[0..1] # => [:foo, "bar"]
+ *    a[1..2] # => ["bar", 2]
+ *
+ *  Special case: If <tt>range.start == a.size</tt>, returns a new empty \Array.
+ *
+ *  If <tt>range.end</tt> is negative, calculates the end index from the end:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[0..-1] # => [:foo, "bar", 2]
+ *    a[0..-2] # => [:foo, "bar"]
+ *    a[0..-3] # => [:foo]
+ *
+ *  If <tt>range.start</tt> is negative, calculates the start index from the end:
  *
+ *    a = [:foo, 'bar', 2]
+ *    a[-1..2] # => [2]
+ *    a[-2..2] # => ["bar", 2]
+ *    a[-3..2] # => [:foo, "bar", 2]
+ *
+ *  If <tt>range.start</tt> is larger than the array size, returns +nil+.
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[4..1] # => nil
+ *    a[4..0] # => nil
+ *    a[4..-1] # => nil
+ *
+ *  When a single Enumerator::ArithmeticSequence argument +aseq+ is given,
+ *  returns an \Array of elements corresponding to the indexes produced by
+ *  the sequence.
+ *
+ *    a = ['--', 'data1', '--', 'data2', '--', 'data3']
+ *    a[(1..).step(2)] # => ["data1", "data2", "data3"]
+ *
+ *  Unlike slicing with range, if the start or the end of the arithmetic sequence
+ *  is larger than array size, throws RangeError.
+ *
+ *    a = ['--', 'data1', '--', 'data2', '--', 'data3']
+ *    a[(1..11).step(2)]
+ *    # RangeError (((1..11).step(2)) out of range)
+ *    a[(7..).step(2)]
+ *    # RangeError (((7..).step(2)) out of range)
+ *
+ *  If given a single argument, and its type is not one of the listed, tries to
+ *  convert it to Integer, and raises if it is impossible:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    # Raises TypeError (no implicit conversion of Symbol into Integer):
+ *    a[:foo]
+ *
+ *  Array#slice is an alias for Array#[].
  */
 
 VALUE
 rb_ary_aref(int argc, const VALUE *argv, VALUE ary)
 {
-    VALUE arg;
-    long beg, len;
-
+    rb_check_arity(argc, 1, 2);
     if (argc == 2) {
-	beg = NUM2LONG(argv[0]);
-	len = NUM2LONG(argv[1]);
-	if (beg < 0) {
-	    beg += RARRAY_LEN(ary);
-	}
-	return rb_ary_subseq(ary, beg, len);
+        return rb_ary_aref2(ary, argv[0], argv[1]);
     }
-    if (argc != 1) {
-	rb_scan_args(argc, argv, "11", NULL, NULL);
+    return rb_ary_aref1(ary, argv[0]);
+}
+
+static VALUE
+rb_ary_aref2(VALUE ary, VALUE b, VALUE e)
+{
+    long beg = NUM2LONG(b);
+    long len = NUM2LONG(e);
+    if (beg < 0) {
+        beg += RARRAY_LEN(ary);
     }
-    arg = argv[0];
+    return rb_ary_subseq(ary, beg, len);
+}
+
+MJIT_FUNC_EXPORTED VALUE
+rb_ary_aref1(VALUE ary, VALUE arg)
+{
+    long beg, len, step;
+
     /* special case - speeding up */
     if (FIXNUM_P(arg)) {
-	return rb_ary_entry(ary, FIX2LONG(arg));
+        return rb_ary_entry(ary, FIX2LONG(arg));
     }
-    /* check if idx is Range */
-    switch (rb_range_beg_len(arg, &beg, &len, RARRAY_LEN(ary), 0)) {
+    /* check if idx is Range or ArithmeticSequence */
+    switch (rb_arithmetic_sequence_beg_len_step(arg, &beg, &len, &step, RARRAY_LEN(ary), 0)) {
       case Qfalse:
-	break;
+        break;
       case Qnil:
-	return Qnil;
+        return Qnil;
       default:
-	return rb_ary_subseq(ary, beg, len);
+        return rb_ary_subseq_step(ary, beg, len, step);
     }
+
     return rb_ary_entry(ary, NUM2LONG(arg));
 }
 
 /*
  *  call-seq:
- *     ary.at(index)   ->   obj  or nil
+ *    array.at(index) -> object
  *
- *  Returns the element at +index+. A negative index counts from the end of
- *  +self+. Returns +nil+ if the index is out of range. See also
- *  Array#[].
+ *  Returns the element at \Integer offset +index+; does not modify +self+.
+ *    a = [:foo, 'bar', 2]
+ *    a.at(0) # => :foo
+ *    a.at(2) # => 2
  *
- *     a = [ "a", "b", "c", "d", "e" ]
- *     a.at(0)     #=> "a"
- *     a.at(-1)    #=> "e"
  */
 
 VALUE
@@ -1317,80 +2035,131 @@ rb_ary_at(VALUE ary, VALUE pos)
 
 /*
  *  call-seq:
- *     ary.first     ->   obj or nil
- *     ary.first(n)  ->   new_ary
+ *    array.first -> object or nil
+ *    array.first(n) -> new_array
+ *
+ *  Returns elements from +self+; does not modify +self+.
+ *
+ *  When no argument is given, returns the first element:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.first # => :foo
+ *    a # => [:foo, "bar", 2]
+ *
+ *  If +self+ is empty, returns +nil+.
  *
- *  Returns the first element, or the first +n+ elements, of the array.
- *  If the array is empty, the first form returns +nil+, and the
- *  second form returns an empty array. See also Array#last for
- *  the opposite effect.
+ *  When non-negative \Integer argument +n+ is given,
+ *  returns the first +n+ elements in a new \Array:
  *
- *     a = [ "q", "r", "s", "t" ]
- *     a.first     #=> "q"
- *     a.first(2)  #=> ["q", "r"]
+ *    a = [:foo, 'bar', 2]
+ *    a.first(2) # => [:foo, "bar"]
+ *
+ *  If <tt>n >= array.size</tt>, returns all elements:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.first(50) # => [:foo, "bar", 2]
+ *
+ *  If <tt>n == 0</tt> returns an new empty \Array:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.first(0) # []
+ *
+ *  Related: #last.
  */
-
 static VALUE
 rb_ary_first(int argc, VALUE *argv, VALUE ary)
 {
     if (argc == 0) {
-	if (RARRAY_LEN(ary) == 0) return Qnil;
-	return RARRAY_AREF(ary, 0);
+        if (RARRAY_LEN(ary) == 0) return Qnil;
+        return RARRAY_AREF(ary, 0);
     }
     else {
-	return ary_take_first_or_last(argc, argv, ary, ARY_TAKE_FIRST);
+        return ary_take_first_or_last(argc, argv, ary, ARY_TAKE_FIRST);
     }
 }
 
 /*
  *  call-seq:
- *     ary.last     ->  obj or nil
- *     ary.last(n)  ->  new_ary
+ *    array.last  -> object or nil
+ *    array.last(n) -> new_array
+ *
+ *  Returns elements from +self+; +self+ is not modified.
+ *
+ *  When no argument is given, returns the last element:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.last # => 2
+ *    a # => [:foo, "bar", 2]
+ *
+ *  If +self+ is empty, returns +nil+.
+ *
+ *  When non-negative \Integer argument +n+ is given,
+ *  returns the last +n+ elements in a new \Array:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.last(2) # => ["bar", 2]
+ *
+ *  If <tt>n >= array.size</tt>, returns all elements:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.last(50) # => [:foo, "bar", 2]
  *
- *  Returns the last element(s) of +self+. If the array is empty,
- *  the first form returns +nil+.
+ *  If <tt>n == 0</tt>, returns an new empty \Array:
  *
- *  See also Array#first for the opposite effect.
+ *    a = [:foo, 'bar', 2]
+ *    a.last(0) # []
  *
- *     a = [ "w", "x", "y", "z" ]
- *     a.last     #=> "z"
- *     a.last(2)  #=> ["y", "z"]
+ *  Related: #first.
  */
 
 VALUE
 rb_ary_last(int argc, const VALUE *argv, VALUE ary)
 {
     if (argc == 0) {
-	long len = RARRAY_LEN(ary);
-	if (len == 0) return Qnil;
-	return RARRAY_AREF(ary, len-1);
+        long len = RARRAY_LEN(ary);
+        if (len == 0) return Qnil;
+        return RARRAY_AREF(ary, len-1);
     }
     else {
-	return ary_take_first_or_last(argc, argv, ary, ARY_TAKE_LAST);
+        return ary_take_first_or_last(argc, argv, ary, ARY_TAKE_LAST);
     }
 }
 
 /*
  *  call-seq:
- *     ary.fetch(index)                    -> obj
- *     ary.fetch(index, default)           -> obj
- *     ary.fetch(index) { |index| block }  -> obj
- *
- *  Tries to return the element at position +index+, but throws an IndexError
- *  exception if the referenced +index+ lies outside of the array bounds.  This
- *  error can be prevented by supplying a second argument, which will act as a
- *  +default+ value.
- *
- *  Alternatively, if a block is given it will only be executed when an
- *  invalid +index+ is referenced.  Negative values of +index+ count from the
- *  end of the array.
- *
- *     a = [ 11, 22, 33, 44 ]
- *     a.fetch(1)               #=> 22
- *     a.fetch(-1)              #=> 44
- *     a.fetch(4, 'cat')        #=> "cat"
- *     a.fetch(100) { |i| puts "#{i} is out of bounds" }
- *                              #=> "100 is out of bounds"
+ *    array.fetch(index) -> element
+ *    array.fetch(index, default_value) -> element
+ *    array.fetch(index) {|index| ... } -> element
+ *
+ *  Returns the element at offset  +index+.
+ *
+ *  With the single \Integer argument +index+,
+ *  returns the element at offset +index+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.fetch(1) # => "bar"
+ *
+ *  If +index+ is negative, counts from the end of the array:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.fetch(-1) # => 2
+ *    a.fetch(-2) # => "bar"
+ *
+ *  With arguments +index+ and +default_value+,
+ *  returns the element at offset +index+ if index is in range,
+ *  otherwise returns +default_value+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.fetch(1, nil) # => "bar"
+ *
+ *  With argument +index+ and a block,
+ *  returns the element at offset +index+ if index is in range
+ *  (and the block is not called); otherwise calls the block with index and returns its return value:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.fetch(1) {|index| raise 'Cannot happen' } # => "bar"
+ *    a.fetch(50) {|index| "Value for #{index}" } # => "Value for 50"
+ *
  */
 
 static VALUE
@@ -1403,149 +2172,152 @@ rb_ary_fetch(int argc, VALUE *argv, VALUE ary)
     rb_scan_args(argc, argv, "11", &pos, &ifnone);
     block_given = rb_block_given_p();
     if (block_given && argc == 2) {
-	rb_warn("block supersedes default value argument");
+        rb_warn("block supersedes default value argument");
     }
     idx = NUM2LONG(pos);
 
     if (idx < 0) {
-	idx +=  RARRAY_LEN(ary);
+        idx +=  RARRAY_LEN(ary);
     }
     if (idx < 0 || RARRAY_LEN(ary) <= idx) {
-	if (block_given) return rb_yield(pos);
-	if (argc == 1) {
-	    rb_raise(rb_eIndexError, "index %ld outside of array bounds: %ld...%ld",
-			idx - (idx < 0 ? RARRAY_LEN(ary) : 0), -RARRAY_LEN(ary), RARRAY_LEN(ary));
-	}
-	return ifnone;
+        if (block_given) return rb_yield(pos);
+        if (argc == 1) {
+            rb_raise(rb_eIndexError, "index %ld outside of array bounds: %ld...%ld",
+                        idx - (idx < 0 ? RARRAY_LEN(ary) : 0), -RARRAY_LEN(ary), RARRAY_LEN(ary));
+        }
+        return ifnone;
     }
     return RARRAY_AREF(ary, idx);
 }
 
 /*
  *  call-seq:
- *     ary.find_index(obj)             ->  int or nil
- *     ary.find_index { |item| block } ->  int or nil
- *     ary.find_index                  ->  Enumerator
- *     ary.index(obj)             ->  int or nil
- *     ary.index { |item| block } ->  int or nil
- *     ary.index                  ->  Enumerator
+ *    array.index(object) -> integer or nil
+ *    array.index {|element| ... } -> integer or nil
+ *    array.index -> new_enumerator
+ *
+ *  Returns the index of a specified element.
+ *
+ *  When argument +object+ is given but no block,
+ *  returns the index of the first element +element+
+ *  for which <tt>object == element</tt>:
  *
- *  Returns the _index_ of the first object in +ary+ such that the object is
- *  <code>==</code> to +obj+.
+ *    a = [:foo, 'bar', 2, 'bar']
+ *    a.index('bar') # => 1
  *
- *  If a block is given instead of an argument, returns the _index_ of the
- *  first object for which the block returns +true+.  Returns +nil+ if no
- *  match is found.
+ *  Returns +nil+ if no such element found.
  *
- *  See also Array#rindex.
+ *  When both argument +object+ and a block are given,
+ *  calls the block with each successive element;
+ *  returns the index of the first element for which the block returns a truthy value:
  *
- *  An Enumerator is returned if neither a block nor argument is given.
+ *    a = [:foo, 'bar', 2, 'bar']
+ *    a.index {|element| element == 'bar' } # => 1
  *
- *     a = [ "a", "b", "c" ]
- *     a.index("b")              #=> 1
- *     a.index("z")              #=> nil
- *     a.index { |x| x == "b" }  #=> 1
+ *  Returns +nil+ if the block never returns a truthy value.
+ *
+ *  When neither an argument nor a block is given, returns a new Enumerator:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    e = a.index
+ *    e # => #<Enumerator: [:foo, "bar", 2]:index>
+ *    e.each {|element| element == 'bar' } # => 1
+ *
+ *  Array#find_index is an alias for Array#index.
+ *
+ *  Related: #rindex.
  */
 
 static VALUE
 rb_ary_index(int argc, VALUE *argv, VALUE ary)
 {
-    const VALUE *ptr;
     VALUE val;
-    long i, len;
+    long i;
 
     if (argc == 0) {
-	RETURN_ENUMERATOR(ary, 0, 0);
-	for (i=0; i<RARRAY_LEN(ary); i++) {
-	    if (RTEST(rb_yield(RARRAY_AREF(ary, i)))) {
-		return LONG2NUM(i);
-	    }
-	}
-	return Qnil;
+        RETURN_ENUMERATOR(ary, 0, 0);
+        for (i=0; i<RARRAY_LEN(ary); i++) {
+            if (RTEST(rb_yield(RARRAY_AREF(ary, i)))) {
+                return LONG2NUM(i);
+            }
+        }
+        return Qnil;
     }
     rb_check_arity(argc, 0, 1);
     val = argv[0];
     if (rb_block_given_p())
-	rb_warn("given block not used");
-    len = RARRAY_LEN(ary);
-    ptr = RARRAY_CONST_PTR(ary);
-    for (i=0; i<len; i++) {
-	VALUE e = ptr[i];
-	switch (rb_equal_opt(e, val)) {
-	  case Qundef:
-	    if (!rb_equal(e, val)) break;
-	  case Qtrue:
-	    return LONG2NUM(i);
-	  case Qfalse:
-	    continue;
-	}
-	len = RARRAY_LEN(ary);
-	ptr = RARRAY_CONST_PTR(ary);
+        rb_warn("given block not used");
+    for (i=0; i<RARRAY_LEN(ary); i++) {
+        VALUE e = RARRAY_AREF(ary, i);
+        if (rb_equal(e, val)) {
+            return LONG2NUM(i);
+        }
     }
     return Qnil;
 }
 
 /*
  *  call-seq:
- *     ary.rindex(obj)             ->  int or nil
- *     ary.rindex { |item| block } ->  int or nil
- *     ary.rindex                  ->  Enumerator
+ *    array.rindex(object) -> integer or nil
+ *    array.rindex {|element| ... } -> integer or nil
+ *    array.rindex -> new_enumerator
+ *
+ *  Returns the index of the last element for which <tt>object == element</tt>.
+ *
+ *  When argument +object+ is given but no block, returns the index of the last such element found:
+ *
+ *    a = [:foo, 'bar', 2, 'bar']
+ *    a.rindex('bar') # => 3
  *
- *  Returns the _index_ of the last object in +self+ <code>==</code> to +obj+.
+ *  Returns +nil+ if no such object found.
  *
- *  If a block is given instead of an argument, returns the _index_ of the
- *  first object for which the block returns +true+, starting from the last
- *  object.
+ *  When a block is given but no argument, calls the block with each successive element;
+ *  returns the index of the last element for which the block returns a truthy value:
  *
- *  Returns +nil+ if no match is found.
+ *    a = [:foo, 'bar', 2, 'bar']
+ *    a.rindex {|element| element == 'bar' } # => 3
  *
- *  See also Array#index.
+ *  Returns +nil+ if the block never returns a truthy value.
  *
- *  If neither block nor argument is given, an Enumerator is returned instead.
+ *  When neither an argument nor a block is given, returns a new \Enumerator:
  *
- *     a = [ "a", "b", "b", "b", "c" ]
- *     a.rindex("b")             #=> 3
- *     a.rindex("z")             #=> nil
- *     a.rindex { |x| x == "b" } #=> 3
+ *    a = [:foo, 'bar', 2, 'bar']
+ *    e = a.rindex
+ *    e # => #<Enumerator: [:foo, "bar", 2, "bar"]:rindex>
+ *    e.each {|element| element == 'bar' } # => 3
+ *
+ *  Related: #index.
  */
 
 static VALUE
 rb_ary_rindex(int argc, VALUE *argv, VALUE ary)
 {
-    const VALUE *ptr;
     VALUE val;
     long i = RARRAY_LEN(ary), len;
 
     if (argc == 0) {
-	RETURN_ENUMERATOR(ary, 0, 0);
-	while (i--) {
-	    if (RTEST(rb_yield(RARRAY_AREF(ary, i))))
-		return LONG2NUM(i);
-	    if (i > (len = RARRAY_LEN(ary))) {
-		i = len;
-	    }
-	}
-	return Qnil;
+        RETURN_ENUMERATOR(ary, 0, 0);
+        while (i--) {
+            if (RTEST(rb_yield(RARRAY_AREF(ary, i))))
+                return LONG2NUM(i);
+            if (i > (len = RARRAY_LEN(ary))) {
+                i = len;
+            }
+        }
+        return Qnil;
     }
     rb_check_arity(argc, 0, 1);
     val = argv[0];
     if (rb_block_given_p())
-	rb_warn("given block not used");
-    ptr = RARRAY_CONST_PTR(ary);
+        rb_warn("given block not used");
     while (i--) {
-	VALUE e = ptr[i];
-	switch (rb_equal_opt(e, val)) {
-	  case Qundef:
-	    if (!rb_equal(e, val)) break;
-	  case Qtrue:
-	    return LONG2NUM(i);
-	  case Qfalse:
-	    continue;
-	}
-	if (i > (len = RARRAY_LEN(ary))) {
-	    i = len;
-	}
-	ptr = RARRAY_CONST_PTR(ary);
+        VALUE e = RARRAY_AREF(ary, i);
+        if (rb_equal(e, val)) {
+            return LONG2NUM(i);
+        }
+        if (i > RARRAY_LEN(ary)) {
+            break;
+        }
     }
     return Qnil;
 }
@@ -1560,68 +2332,73 @@ rb_ary_to_ary(VALUE obj)
 }
 
 static void
-rb_ary_splice(VALUE ary, long beg, long len, VALUE rpl)
+rb_ary_splice(VALUE ary, long beg, long len, const VALUE *rptr, long rlen)
 {
-    long rlen;
     long olen;
+    long rofs;
 
     if (len < 0) rb_raise(rb_eIndexError, "negative length (%ld)", len);
     olen = RARRAY_LEN(ary);
     if (beg < 0) {
-	beg += olen;
-	if (beg < 0) {
-	    rb_raise(rb_eIndexError, "index %ld too small for array; minimum: %ld",
-		     beg - olen, -olen);
-	}
+        beg += olen;
+        if (beg < 0) {
+            rb_raise(rb_eIndexError, "index %ld too small for array; minimum: %ld",
+                     beg - olen, -olen);
+        }
     }
     if (olen < len || olen < beg + len) {
-	len = olen - beg;
+        len = olen - beg;
     }
 
-    if (rpl == Qundef) {
-	rlen = 0;
-    }
-    else {
-	rpl = rb_ary_to_ary(rpl);
-	rlen = RARRAY_LEN(rpl);
-	olen = RARRAY_LEN(ary);	/* ary may be resized in rpl.to_ary too */
+    {
+        const VALUE *optr = RARRAY_CONST_PTR_TRANSIENT(ary);
+        rofs = (rptr >= optr && rptr < optr + olen) ? rptr - optr : -1;
     }
+
     if (beg >= olen) {
-	VALUE target_ary;
-	if (beg > ARY_MAX_SIZE - rlen) {
-	    rb_raise(rb_eIndexError, "index %ld too big", beg);
-	}
-	target_ary = ary_ensure_room_for_push(ary, rlen-len); /* len is 0 or negative */
-	len = beg + rlen;
-	ary_mem_clear(ary, olen, beg - olen);
-	if (rlen > 0) {
-	    ary_memcpy0(ary, beg, rlen, RARRAY_CONST_PTR(rpl), target_ary);
-	}
-	ARY_SET_LEN(ary, len);
+        VALUE target_ary;
+        if (beg > ARY_MAX_SIZE - rlen) {
+            rb_raise(rb_eIndexError, "index %ld too big", beg);
+        }
+        target_ary = ary_ensure_room_for_push(ary, rlen-len); /* len is 0 or negative */
+        len = beg + rlen;
+        ary_mem_clear(ary, olen, beg - olen);
+        if (rlen > 0) {
+            if (rofs != -1) rptr = RARRAY_CONST_PTR_TRANSIENT(ary) + rofs;
+            ary_memcpy0(ary, beg, rlen, rptr, target_ary);
+        }
+        ARY_SET_LEN(ary, len);
     }
     else {
-	long alen;
-
-	if (olen - len > ARY_MAX_SIZE - rlen) {
-	    rb_raise(rb_eIndexError, "index %ld too big", olen + rlen - len);
-	}
-	rb_ary_modify(ary);
-	alen = olen + rlen - len;
-	if (alen >= ARY_CAPA(ary)) {
-	    ary_double_capa(ary, alen);
-	}
-
-	if (len != rlen) {
-	    RARRAY_PTR_USE(ary, ptr,
-			   MEMMOVE(ptr + beg + rlen, ptr + beg + len,
-				   VALUE, olen - (beg + len)));
-	    ARY_SET_LEN(ary, alen);
-	}
-	if (rlen > 0) {
-	    MEMMOVE(RARRAY_PTR(ary) + beg, RARRAY_CONST_PTR(rpl), VALUE, rlen);
-	}
+        long alen;
+
+        if (olen - len > ARY_MAX_SIZE - rlen) {
+            rb_raise(rb_eIndexError, "index %ld too big", olen + rlen - len);
+        }
+        rb_ary_modify(ary);
+        alen = olen + rlen - len;
+        if (alen >= ARY_CAPA(ary)) {
+            ary_double_capa(ary, alen);
+        }
+
+        if (len != rlen) {
+            RARRAY_PTR_USE_TRANSIENT(ary, ptr,
+                                     MEMMOVE(ptr + beg + rlen, ptr + beg + len,
+                                             VALUE, olen - (beg + len)));
+            ARY_SET_LEN(ary, alen);
+        }
+        if (rlen > 0) {
+            if (rofs != -1) rptr = RARRAY_CONST_PTR_TRANSIENT(ary) + rofs;
+            /* give up wb-protected ary */
+            RB_OBJ_WB_UNPROTECT_FOR(ARRAY, ary);
+
+            /* do not use RARRAY_PTR() because it can causes GC.
+             * ary can contain T_NONE object because it is not cleared.
+             */
+            RARRAY_PTR_USE_TRANSIENT(ary, ptr,
+                                     MEMMOVE(ptr + beg, rptr, VALUE, rlen));
+        }
     }
-    RB_GC_GUARD(rpl);
 }
 
 void
@@ -1631,22 +2408,14 @@ rb_ary_set_len(VALUE ary, long len)
 
     rb_ary_modify_check(ary);
     if (ARY_SHARED_P(ary)) {
-	rb_raise(rb_eRuntimeError, "can't set length of shared ");
+        rb_raise(rb_eRuntimeError, "can't set length of shared ");
     }
     if (len > (capa = (long)ARY_CAPA(ary))) {
-	rb_bug("probable buffer overflow: %ld for %ld", len, capa);
+        rb_bug("probable buffer overflow: %ld for %ld", len, capa);
     }
     ARY_SET_LEN(ary, len);
 }
 
-/*!
- * expands or shrinks \a ary to \a len elements.
- * expanded region will be filled with Qnil.
- * \param ary  an array
- * \param len  new size
- * \return     \a ary
- * \post       the size of \a ary is \a len.
- */
 VALUE
 rb_ary_resize(VALUE ary, long len)
 {
@@ -1656,68 +2425,170 @@ rb_ary_resize(VALUE ary, long len)
     olen = RARRAY_LEN(ary);
     if (len == olen) return ary;
     if (len > ARY_MAX_SIZE) {
-	rb_raise(rb_eIndexError, "index %ld too big", len);
+        rb_raise(rb_eIndexError, "index %ld too big", len);
     }
     if (len > olen) {
-	if (len >= ARY_CAPA(ary)) {
-	    ary_double_capa(ary, len);
-	}
-	ary_mem_clear(ary, olen, len - olen);
-	ARY_SET_LEN(ary, len);
+        if (len >= ARY_CAPA(ary)) {
+            ary_double_capa(ary, len);
+        }
+        ary_mem_clear(ary, olen, len - olen);
+        ARY_SET_LEN(ary, len);
     }
     else if (ARY_EMBED_P(ary)) {
         ARY_SET_EMBED_LEN(ary, len);
     }
-    else if (len <= RARRAY_EMBED_LEN_MAX) {
-	VALUE tmp[RARRAY_EMBED_LEN_MAX];
-	MEMCPY(tmp, ARY_HEAP_PTR(ary), VALUE, len);
-	ary_discard(ary);
-	MEMCPY((VALUE *)ARY_EMBED_PTR(ary), tmp, VALUE, len); /* WB: no new reference */
+    else if (len <= ary_embed_capa(ary)) {
+        const VALUE *ptr = ARY_HEAP_PTR(ary);
+        long ptr_capa = ARY_HEAP_SIZE(ary);
+        bool is_malloc_ptr = !ARY_SHARED_P(ary) && !RARRAY_TRANSIENT_P(ary);
+
+        FL_UNSET(ary, RARRAY_TRANSIENT_FLAG);
+        FL_SET_EMBED(ary);
+
+        MEMCPY((VALUE *)ARY_EMBED_PTR(ary), ptr, VALUE, len); /* WB: no new reference */
         ARY_SET_EMBED_LEN(ary, len);
+
+        if (is_malloc_ptr) ruby_sized_xfree((void *)ptr, ptr_capa);
     }
     else {
-	if (olen > len + ARY_DEFAULT_SIZE) {
-	    SIZED_REALLOC_N(RARRAY(ary)->as.heap.ptr, VALUE, len, RARRAY(ary)->as.heap.aux.capa);
-	    ARY_SET_CAPA(ary, len);
-	}
-	ARY_SET_HEAP_LEN(ary, len);
+        if (olen > len + ARY_DEFAULT_SIZE) {
+            size_t new_capa = ary_heap_realloc(ary, len);
+            ARY_SET_CAPA(ary, new_capa);
+        }
+        ARY_SET_HEAP_LEN(ary, len);
     }
+    ary_verify(ary);
     return ary;
 }
 
+static VALUE
+ary_aset_by_rb_ary_store(VALUE ary, long key, VALUE val)
+{
+    rb_ary_store(ary, key, val);
+    return val;
+}
+
+static VALUE
+ary_aset_by_rb_ary_splice(VALUE ary, long beg, long len, VALUE val)
+{
+    VALUE rpl = rb_ary_to_ary(val);
+    rb_ary_splice(ary, beg, len, RARRAY_CONST_PTR_TRANSIENT(rpl), RARRAY_LEN(rpl));
+    RB_GC_GUARD(rpl);
+    return val;
+}
+
 /*
  *  call-seq:
- *     ary[index]         = obj                      ->  obj
- *     ary[start, length] = obj or other_ary or nil  ->  obj or other_ary or nil
- *     ary[range]         = obj or other_ary or nil  ->  obj or other_ary or nil
- *
- *  Element Assignment --- Sets the element at +index+, or replaces a subarray
- *  from the +start+ index for +length+ elements, or replaces a subarray
- *  specified by the +range+ of indices.
- *
- *  If indices are greater than the current capacity of the array, the array
- *  grows automatically.  Elements are inserted into the array at +start+ if
- *  +length+ is zero.
- *
- *  Negative indices will count backward from the end of the array.  For
- *  +start+ and +range+ cases the starting index is just before an element.
- *
- *  An IndexError is raised if a negative index points past the beginning of
- *  the array.
- *
- *  See also Array#push, and Array#unshift.
- *
- *     a = Array.new
- *     a[4] = "4";                 #=> [nil, nil, nil, nil, "4"]
- *     a[0, 3] = [ 'a', 'b', 'c' ] #=> ["a", "b", "c", nil, "4"]
- *     a[1..2] = [ 1, 2 ]          #=> ["a", 1, 2, nil, "4"]
- *     a[0, 2] = "?"               #=> ["?", 2, nil, "4"]
- *     a[0..2] = "A"               #=> ["A", "4"]
- *     a[-1]   = "Z"               #=> ["A", "Z"]
- *     a[1..-1] = nil              #=> ["A", nil]
- *     a[1..-1] = []               #=> ["A"]
- *     a[0, 0] = [ 1, 2 ]          #=> [1, 2, "A"]
- *     a[3, 0] = "B"               #=> [1, 2, "A", "B"]
+ *    array[index] = object -> object
+ *    array[start, length] = object -> object
+ *    array[range] = object -> object
+ *
+ *  Assigns elements in +self+; returns the given +object+.
+ *
+ *  When \Integer argument +index+ is given, assigns +object+ to an element in +self+.
+ *
+ *  If +index+ is non-negative, assigns +object+ the element at offset +index+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[0] = 'foo' # => "foo"
+ *    a # => ["foo", "bar", 2]
+ *
+ *  If +index+ is greater than <tt>self.length</tt>, extends the array:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[7] = 'foo' # => "foo"
+ *    a # => [:foo, "bar", 2, nil, nil, nil, nil, "foo"]
+ *
+ *  If +index+ is negative, counts backwards from the end of the array:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[-1] = 'two' # => "two"
+ *    a # => [:foo, "bar", "two"]
+ *
+ *  When \Integer arguments +start+ and +length+ are given and +object+ is not an \Array,
+ *  removes <tt>length - 1</tt> elements beginning at offset +start+,
+ *  and assigns +object+ at offset +start+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[0, 2] = 'foo' # => "foo"
+ *    a # => ["foo", 2]
+ *
+ *  If +start+ is negative, counts backwards from the end of the array:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[-2, 2] = 'foo' # => "foo"
+ *    a # => [:foo, "foo"]
+ *
+ *  If +start+ is non-negative and outside the array (<tt> >= self.size</tt>),
+ *  extends the array with +nil+, assigns +object+ at offset +start+,
+ *  and ignores +length+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[6, 50] = 'foo' # => "foo"
+ *    a # => [:foo, "bar", 2, nil, nil, nil, "foo"]
+ *
+ *  If +length+ is zero, shifts elements at and following offset +start+
+ *  and assigns +object+ at offset +start+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[1, 0] = 'foo' # => "foo"
+ *    a # => [:foo, "foo", "bar", 2]
+ *
+ *  If +length+ is too large for the existing array, does not extend the array:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[1, 5] = 'foo' # => "foo"
+ *    a # => [:foo, "foo"]
+ *
+ *  When \Range argument +range+ is given and +object+ is an \Array,
+ *  removes <tt>length - 1</tt> elements beginning at offset +start+,
+ *  and assigns +object+ at offset +start+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[0..1] = 'foo' # => "foo"
+ *    a # => ["foo", 2]
+ *
+ *  if <tt>range.begin</tt> is negative, counts backwards from the end of the array:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[-2..2] = 'foo' # => "foo"
+ *    a # => [:foo, "foo"]
+ *
+ *  If the array length is less than <tt>range.begin</tt>,
+ *  assigns +object+ at offset <tt>range.begin</tt>, and ignores +length+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[6..50] = 'foo' # => "foo"
+ *    a # => [:foo, "bar", 2, nil, nil, nil, "foo"]
+ *
+ *  If <tt>range.end</tt> is zero, shifts elements at and following offset +start+
+ *  and assigns +object+ at offset +start+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[1..0] = 'foo' # => "foo"
+ *    a # => [:foo, "foo", "bar", 2]
+ *
+ *  If <tt>range.end</tt> is negative, assigns +object+ at offset +start+,
+ *  retains <tt>range.end.abs -1</tt> elements past that, and removes those beyond:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[1..-1] = 'foo' # => "foo"
+ *    a # => [:foo, "foo"]
+ *    a = [:foo, 'bar', 2]
+ *    a[1..-2] = 'foo' # => "foo"
+ *    a # => [:foo, "foo", 2]
+ *    a = [:foo, 'bar', 2]
+ *    a[1..-3] = 'foo' # => "foo"
+ *    a # => [:foo, "foo", "bar", 2]
+ *    a = [:foo, 'bar', 2]
+ *
+ *  If <tt>range.end</tt> is too large for the existing array,
+ *  replaces array elements, but does not extend the array with +nil+ values:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a[1..5] = 'foo' # => "foo"
+ *    a # => [:foo, "foo"]
+ *
  */
 
 static VALUE
@@ -1725,45 +2596,60 @@ rb_ary_aset(int argc, VALUE *argv, VALUE ary)
 {
     long offset, beg, len;
 
+    rb_check_arity(argc, 2, 3);
+    rb_ary_modify_check(ary);
     if (argc == 3) {
-	rb_ary_modify_check(ary);
-	beg = NUM2LONG(argv[0]);
-	len = NUM2LONG(argv[1]);
-	rb_ary_splice(ary, beg, len, argv[2]);
-	return argv[2];
+        beg = NUM2LONG(argv[0]);
+        len = NUM2LONG(argv[1]);
+        return ary_aset_by_rb_ary_splice(ary, beg, len, argv[2]);
     }
-    rb_check_arity(argc, 2, 2);
-    rb_ary_modify_check(ary);
     if (FIXNUM_P(argv[0])) {
-	offset = FIX2LONG(argv[0]);
-	goto fixnum;
+        offset = FIX2LONG(argv[0]);
+        return ary_aset_by_rb_ary_store(ary, offset, argv[1]);
     }
     if (rb_range_beg_len(argv[0], &beg, &len, RARRAY_LEN(ary), 1)) {
-	/* check if idx is Range */
-	rb_ary_splice(ary, beg, len, argv[1]);
-	return argv[1];
+        /* check if idx is Range */
+        return ary_aset_by_rb_ary_splice(ary, beg, len, argv[1]);
     }
 
     offset = NUM2LONG(argv[0]);
-fixnum:
-    rb_ary_store(ary, offset, argv[1]);
-    return argv[1];
+    return ary_aset_by_rb_ary_store(ary, offset, argv[1]);
 }
 
 /*
  *  call-seq:
- *     ary.insert(index, obj...)  -> ary
+ *    array.insert(index, *objects) -> self
+ *
+ *  Inserts given +objects+ before or after the element at \Integer index +offset+;
+ *  returns +self+.
+ *
+ *  When +index+ is non-negative, inserts all given +objects+
+ *  before the element at offset +index+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.insert(1, :bat, :bam) # => [:foo, :bat, :bam, "bar", 2]
+ *
+ *  Extends the array if +index+ is beyond the array (<tt>index >= self.size</tt>):
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.insert(5, :bat, :bam)
+ *    a # => [:foo, "bar", 2, nil, nil, :bat, :bam]
+ *
+ *  Does nothing if no objects given:
  *
- *  Inserts the given values before the element with the given +index+.
+ *    a = [:foo, 'bar', 2]
+ *    a.insert(1)
+ *    a.insert(50)
+ *    a.insert(-50)
+ *    a # => [:foo, "bar", 2]
  *
- *  Negative indices count backwards from the end of the array, where +-1+ is
- *  the last element. If a negative index is used, the given values will be
- *  inserted after that element, so using an index of +-1+ will insert the
- *  values at the end of the array.
+ *  When +index+ is negative, inserts all given +objects+
+ *  _after_ the element at offset <tt>index+self.size</tt>:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.insert(-2, :bat, :bam)
+ *    a # => [:foo, "bar", :bat, :bam, 2]
  *
- *     a = %w{ a b c d }
- *     a.insert(2, 99)         #=> ["a", "b", 99, "c", "d"]
- *     a.insert(-2, 1, 2, 3)   #=> ["a", "b", 99, "c", 1, 2, 3, "d"]
  */
 
 static VALUE
@@ -1773,15 +2659,20 @@ rb_ary_insert(int argc, VALUE *argv, VALUE ary)
 
     rb_check_arity(argc, 1, UNLIMITED_ARGUMENTS);
     rb_ary_modify_check(ary);
-    if (argc == 1) return ary;
     pos = NUM2LONG(argv[0]);
+    if (argc == 1) return ary;
     if (pos == -1) {
-	pos = RARRAY_LEN(ary);
+        pos = RARRAY_LEN(ary);
     }
-    if (pos < 0) {
-	pos++;
+    else if (pos < 0) {
+        long minpos = -RARRAY_LEN(ary) - 1;
+        if (pos < minpos) {
+            rb_raise(rb_eIndexError, "index %ld too small for array; minimum: %ld",
+                     pos, minpos);
+        }
+        pos++;
     }
-    rb_ary_splice(ary, pos, 0, rb_ary_new4(argc - 1, argv + 1));
+    rb_ary_splice(ary, pos, 0, argv + 1, argc - 1);
     return ary;
 }
 
@@ -1796,50 +2687,104 @@ ary_enum_length(VALUE ary, VALUE args, VALUE eobj)
 
 /*
  *  call-seq:
- *     ary.each { |item| block }  -> ary
- *     ary.each                   -> Enumerator
+ *    array.each {|element| ... } -> self
+ *    array.each -> Enumerator
+ *
+ *  Iterates over array elements.
+ *
+ *  When a block given, passes each successive array element to the block;
+ *  returns +self+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.each {|element|  puts "#{element.class} #{element}" }
+ *
+ *  Output:
+ *
+ *    Symbol foo
+ *    String bar
+ *    Integer 2
+ *
+ *  Allows the array to be modified during iteration:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.each {|element| puts element; a.clear if element.to_s.start_with?('b') }
+ *
+ *  Output:
  *
- *  Calls the given block once for each element in +self+, passing that element
- *  as a parameter.  Returns the array itself.
+ *    foo
+ *    bar
  *
- *  If no block is given, an Enumerator is returned.
+ *  When no block given, returns a new \Enumerator:
+ *    a = [:foo, 'bar', 2]
  *
- *     a = [ "a", "b", "c" ]
- *     a.each {|x| print x, " -- " }
+ *    e = a.each
+ *    e # => #<Enumerator: [:foo, "bar", 2]:each>
+ *    a1 = e.each {|element|  puts "#{element.class} #{element}" }
  *
- *  produces:
+ *  Output:
  *
- *     a -- b -- c --
+ *    Symbol foo
+ *    String bar
+ *    Integer 2
+ *
+ *  Related: #each_index, #reverse_each.
  */
 
 VALUE
 rb_ary_each(VALUE ary)
 {
     long i;
-
+    ary_verify(ary);
     RETURN_SIZED_ENUMERATOR(ary, 0, 0, ary_enum_length);
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	rb_yield(RARRAY_AREF(ary, i));
+        rb_yield(RARRAY_AREF(ary, i));
     }
     return ary;
 }
 
 /*
  *  call-seq:
- *     ary.each_index { |index| block }  -> ary
- *     ary.each_index                    -> Enumerator
+ *    array.each_index {|index| ... } -> self
+ *    array.each_index -> Enumerator
+ *
+ *  Iterates over array indexes.
+ *
+ *  When a block given, passes each successive array index to the block;
+ *  returns +self+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.each_index {|index|  puts "#{index} #{a[index]}" }
+ *
+ *  Output:
+ *
+ *    0 foo
+ *    1 bar
+ *    2 2
  *
- *  Same as Array#each, but passes the +index+ of the element instead of the
- *  element itself.
+ *  Allows the array to be modified during iteration:
  *
- *  An Enumerator is returned if no block is given.
+ *    a = [:foo, 'bar', 2]
+ *    a.each_index {|index| puts index; a.clear if index > 0 }
  *
- *     a = [ "a", "b", "c" ]
- *     a.each_index {|x| print x, " -- " }
+ *  Output:
  *
- *  produces:
+ *    0
+ *    1
  *
- *     0 -- 1 -- 2 --
+ *  When no block given, returns a new \Enumerator:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    e = a.each_index
+ *    e # => #<Enumerator: [:foo, "bar", 2]:each_index>
+ *    a1 = e.each {|index|  puts "#{index} #{a[index]}"}
+ *
+ *  Output:
+ *
+ *    0 foo
+ *    1 bar
+ *    2 2
+ *
+ *  Related: #each, #reverse_each.
  */
 
 static VALUE
@@ -1849,24 +2794,54 @@ rb_ary_each_index(VALUE ary)
     RETURN_SIZED_ENUMERATOR(ary, 0, 0, ary_enum_length);
 
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	rb_yield(LONG2NUM(i));
+        rb_yield(LONG2NUM(i));
     }
     return ary;
 }
 
 /*
  *  call-seq:
- *     ary.reverse_each { |item| block }  -> ary
- *     ary.reverse_each                   -> Enumerator
+ *    array.reverse_each {|element| ... } -> self
+ *    array.reverse_each -> Enumerator
+ *
+ *  Iterates backwards over array elements.
+ *
+ *  When a block given, passes, in reverse order, each element to the block;
+ *  returns +self+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.reverse_each {|element|  puts "#{element.class} #{element}" }
  *
- *  Same as Array#each, but traverses +self+ in reverse order.
+ *  Output:
  *
- *     a = [ "a", "b", "c" ]
- *     a.reverse_each {|x| print x, " " }
+ *    Integer 2
+ *    String bar
+ *    Symbol foo
  *
- *  produces:
+ *  Allows the array to be modified during iteration:
  *
- *     c b a
+ *    a = [:foo, 'bar', 2]
+ *    a.reverse_each {|element| puts element; a.clear if element.to_s.start_with?('b') }
+ *
+ *  Output:
+ *
+ *    2
+ *    bar
+ *
+ *  When no block given, returns a new \Enumerator:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    e = a.reverse_each
+ *    e # => #<Enumerator: [:foo, "bar", 2]:reverse_each>
+ *    a1 = e.each {|element|  puts "#{element.class} #{element}" }
+ *
+ *  Output:
+ *
+ *    Integer 2
+ *    String bar
+ *    Symbol foo
+ *
+ *  Related: #each, #each_index.
  */
 
 static VALUE
@@ -1877,24 +2852,21 @@ rb_ary_reverse_each(VALUE ary)
     RETURN_SIZED_ENUMERATOR(ary, 0, 0, ary_enum_length);
     len = RARRAY_LEN(ary);
     while (len--) {
-	long nlen;
-	rb_yield(RARRAY_AREF(ary, len));
-	nlen = RARRAY_LEN(ary);
-	if (nlen < len) {
-	    len = nlen;
-	}
+        long nlen;
+        rb_yield(RARRAY_AREF(ary, len));
+        nlen = RARRAY_LEN(ary);
+        if (nlen < len) {
+            len = nlen;
+        }
     }
     return ary;
 }
 
 /*
  *  call-seq:
- *     ary.length -> int
- *
- *  Returns the number of elements in +self+. May be zero.
+ *    array.length -> an_integer
  *
- *     [ 1, 2, 3, 4, 5 ].length   #=> 5
- *     [].length                  #=> 0
+ *  Returns the count of elements in +self+.
  */
 
 static VALUE
@@ -1906,19 +2878,16 @@ rb_ary_length(VALUE ary)
 
 /*
  *  call-seq:
- *     ary.empty?   -> true or false
- *
- *  Returns +true+ if +self+ contains no elements.
+ *    array.empty?  -> true or false
  *
- *     [].empty?   #=> true
+ *  Returns +true+ if the count of elements in +self+ is zero,
+ *  +false+ otherwise.
  */
 
 static VALUE
 rb_ary_empty_p(VALUE ary)
 {
-    if (RARRAY_LEN(ary) == 0)
-	return Qtrue;
-    return Qfalse;
+    return RBOOL(RARRAY_LEN(ary) == 0);
 }
 
 VALUE
@@ -1926,15 +2895,18 @@ rb_ary_dup(VALUE ary)
 {
     long len = RARRAY_LEN(ary);
     VALUE dup = rb_ary_new2(len);
-    ary_memcpy(dup, 0, len, RARRAY_CONST_PTR(ary));
+    ary_memcpy(dup, 0, len, RARRAY_CONST_PTR_TRANSIENT(ary));
     ARY_SET_LEN(dup, len);
+
+    ary_verify(ary);
+    ary_verify(dup);
     return dup;
 }
 
 VALUE
 rb_ary_resurrect(VALUE ary)
 {
-    return rb_ary_new4(RARRAY_LEN(ary), RARRAY_CONST_PTR(ary));
+    return ary_make_partial(ary, rb_cArray, 0, RARRAY_LEN(ary));
 }
 
 extern VALUE rb_output_fs;
@@ -1951,15 +2923,15 @@ recursive_join(VALUE obj, VALUE argp, int recur)
     int *first = (int *)arg[3];
 
     if (recur) {
-	rb_raise(rb_eArgError, "recursive array join");
+        rb_raise(rb_eArgError, "recursive array join");
     }
     else {
-	ary_join_1(obj, ary, sep, 0, result, first);
+        ary_join_1(obj, ary, sep, 0, result, first);
     }
     return Qnil;
 }
 
-static void
+static long
 ary_join_0(VALUE ary, VALUE sep, long max, VALUE result)
 {
     long i;
@@ -1967,11 +2939,40 @@ ary_join_0(VALUE ary, VALUE sep, long max, VALUE result)
 
     if (max > 0) rb_enc_copy(result, RARRAY_AREF(ary, 0));
     for (i=0; i<max; i++) {
-	val = RARRAY_AREF(ary, i);
-	if (i > 0 && !NIL_P(sep))
-	    rb_str_buf_append(result, sep);
-	rb_str_buf_append(result, val);
-	if (OBJ_TAINTED(val)) OBJ_TAINT(result);
+        val = RARRAY_AREF(ary, i);
+        if (!RB_TYPE_P(val, T_STRING)) break;
+        if (i > 0 && !NIL_P(sep))
+            rb_str_buf_append(result, sep);
+        rb_str_buf_append(result, val);
+    }
+    return i;
+}
+
+static void
+ary_join_1_str(VALUE dst, VALUE src, int *first)
+{
+    rb_str_buf_append(dst, src);
+    if (*first) {
+        rb_enc_copy(dst, src);
+        *first = FALSE;
+    }
+}
+
+static void
+ary_join_1_ary(VALUE obj, VALUE ary, VALUE sep, VALUE result, VALUE val, int *first)
+{
+    if (val == ary) {
+        rb_raise(rb_eArgError, "recursive array join");
+    }
+    else {
+        VALUE args[4];
+
+        *first = FALSE;
+        args[0] = val;
+        args[1] = sep;
+        args[2] = result;
+        args[3] = (VALUE)first;
+        rb_exec_recursive(recursive_join, obj, (VALUE)args);
     }
 }
 
@@ -1981,50 +2982,25 @@ ary_join_1(VALUE obj, VALUE ary, VALUE sep, long i, VALUE result, int *first)
     VALUE val, tmp;
 
     for (; i<RARRAY_LEN(ary); i++) {
-	if (i > 0 && !NIL_P(sep))
-	    rb_str_buf_append(result, sep);
-
-	val = RARRAY_AREF(ary, i);
-	if (RB_TYPE_P(val, T_STRING)) {
-	  str_join:
-	    rb_str_buf_append(result, val);
-	    *first = FALSE;
-	}
-	else if (RB_TYPE_P(val, T_ARRAY)) {
-	    obj = val;
-	  ary_join:
-	    if (val == ary) {
-		rb_raise(rb_eArgError, "recursive array join");
-	    }
-	    else {
-		VALUE args[4];
-
-		args[0] = val;
-		args[1] = sep;
-		args[2] = result;
-		args[3] = (VALUE)first;
-		rb_exec_recursive(recursive_join, obj, (VALUE)args);
-	    }
-	}
-	else {
-	    tmp = rb_check_string_type(val);
-	    if (!NIL_P(tmp)) {
-		val = tmp;
-		goto str_join;
-	    }
-	    tmp = rb_check_convert_type(val, T_ARRAY, "Array", "to_ary");
-	    if (!NIL_P(tmp)) {
-		obj = val;
-		val = tmp;
-		goto ary_join;
-	    }
-	    val = rb_obj_as_string(val);
-	    if (*first) {
-		rb_enc_copy(result, val);
-		*first = FALSE;
-	    }
-	    goto str_join;
-	}
+        if (i > 0 && !NIL_P(sep))
+            rb_str_buf_append(result, sep);
+
+        val = RARRAY_AREF(ary, i);
+        if (RB_TYPE_P(val, T_STRING)) {
+            ary_join_1_str(result, val, first);
+        }
+        else if (RB_TYPE_P(val, T_ARRAY)) {
+            ary_join_1_ary(val, ary, sep, result, val, first);
+        }
+        else if (!NIL_P(tmp = rb_check_string_type(val))) {
+            ary_join_1_str(result, tmp, first);
+        }
+        else if (!NIL_P(tmp = rb_check_array_type(val))) {
+            ary_join_1_ary(val, ary, sep, result, tmp, first);
+        }
+        else {
+            ary_join_1_str(result, rb_obj_as_string(val), first);
+        }
     }
 }
 
@@ -2032,36 +3008,36 @@ VALUE
 rb_ary_join(VALUE ary, VALUE sep)
 {
     long len = 1, i;
-    int taint = FALSE;
     VALUE val, tmp, result;
 
     if (RARRAY_LEN(ary) == 0) return rb_usascii_str_new(0, 0);
-    if (OBJ_TAINTED(ary)) taint = TRUE;
 
     if (!NIL_P(sep)) {
-	StringValue(sep);
-	len += RSTRING_LEN(sep) * (RARRAY_LEN(ary) - 1);
+        StringValue(sep);
+        len += RSTRING_LEN(sep) * (RARRAY_LEN(ary) - 1);
     }
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	val = RARRAY_AREF(ary, i);
-	tmp = rb_check_string_type(val);
-
-	if (NIL_P(tmp) || tmp != val) {
-	    int first;
-	    result = rb_str_buf_new(len + (RARRAY_LEN(ary)-i)*10);
-	    rb_enc_associate(result, rb_usascii_encoding());
-	    if (taint) OBJ_TAINT(result);
-	    ary_join_0(ary, sep, i, result);
-	    first = i == 0;
-	    ary_join_1(ary, ary, sep, i, result, &first);
-	    return result;
-	}
+        val = RARRAY_AREF(ary, i);
+        tmp = rb_check_string_type(val);
+
+        if (NIL_P(tmp) || tmp != val) {
+            int first;
+            long n = RARRAY_LEN(ary);
+            if (i > n) i = n;
+            result = rb_str_buf_new(len + (n-i)*10);
+            rb_enc_associate(result, rb_usascii_encoding());
+            i = ary_join_0(ary, sep, i, result);
+            first = i == 0;
+            ary_join_1(ary, ary, sep, i, result, &first);
+            return result;
+        }
 
-	len += RSTRING_LEN(tmp);
+        len += RSTRING_LEN(tmp);
     }
 
-    result = rb_str_buf_new(len);
-    if (taint) OBJ_TAINT(result);
+    result = rb_str_new(0, len);
+    rb_str_set_len(result, 0);
+
     ary_join_0(ary, sep, RARRAY_LEN(ary), result);
 
     return result;
@@ -2069,24 +3045,43 @@ rb_ary_join(VALUE ary, VALUE sep)
 
 /*
  *  call-seq:
- *     ary.join(separator=$,)    -> str
+ *    array.join ->new_string
+ *    array.join(separator = $,) -> new_string
+ *
+ *  Returns the new \String formed by joining the array elements after conversion.
+ *  For each element +element+:
+ *
+ *  - Uses <tt>element.to_s</tt> if +element+ is not a <tt>kind_of?(Array)</tt>.
+ *  - Uses recursive <tt>element.join(separator)</tt> if +element+ is a <tt>kind_of?(Array)</tt>.
+ *
+ *  With no argument, joins using the output field separator, <tt>$,</tt>:
  *
- *  Returns a string created by converting each element of the array to
- *  a string, separated by the given +separator+.
- *  If the +separator+ is +nil+, it uses current $,.
- *  If both the +separator+ and $, are nil, it uses empty string.
+ *    a = [:foo, 'bar', 2]
+ *    $, # => nil
+ *    a.join # => "foobar2"
+ *
+ *  With \string argument +separator+, joins using that separator:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.join("\n") # => "foo\nbar\n2"
+ *
+ *  Joins recursively for nested Arrays:
+ *
+ *   a = [:foo, [:bar, [:baz, :bat]]]
+ *   a.join # => "foobarbazbat"
  *
- *     [ "a", "b", "c" ].join        #=> "abc"
- *     [ "a", "b", "c" ].join("-")   #=> "a-b-c"
  */
-
 static VALUE
 rb_ary_join_m(int argc, VALUE *argv, VALUE ary)
 {
     VALUE sep;
 
-    rb_scan_args(argc, argv, "01", &sep);
-    if (NIL_P(sep)) sep = rb_output_fs;
+    if (rb_check_arity(argc, 0, 1) == 0 || NIL_P(sep = argv[0])) {
+        sep = rb_output_fs;
+        if (!NIL_P(sep)) {
+            rb_category_warn(RB_WARN_CATEGORY_DEPRECATED, "$, is set to non-nil value");
+        }
+    }
 
     return rb_ary_join(ary, sep);
 }
@@ -2094,32 +3089,32 @@ rb_ary_join_m(int argc, VALUE *argv, VALUE ary)
 static VALUE
 inspect_ary(VALUE ary, VALUE dummy, int recur)
 {
-    int tainted = OBJ_TAINTED(ary);
     long i;
     VALUE s, str;
 
     if (recur) return rb_usascii_str_new_cstr("[...]");
     str = rb_str_buf_new2("[");
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	s = rb_inspect(RARRAY_AREF(ary, i));
-	if (OBJ_TAINTED(s)) tainted = TRUE;
-	if (i > 0) rb_str_buf_cat2(str, ", ");
-	else rb_enc_copy(str, s);
-	rb_str_buf_append(str, s);
+        s = rb_inspect(RARRAY_AREF(ary, i));
+        if (i > 0) rb_str_buf_cat2(str, ", ");
+        else rb_enc_copy(str, s);
+        rb_str_buf_append(str, s);
     }
     rb_str_buf_cat2(str, "]");
-    if (tainted) OBJ_TAINT(str);
     return str;
 }
 
 /*
  *  call-seq:
- *     ary.inspect  -> string
- *     ary.to_s     -> string
+ *    array.inspect -> new_string
  *
- *  Creates a string representation of +self+.
+ *  Returns the new \String formed by calling method <tt>#inspect</tt>
+ *  on each array element:
  *
- *     [ "a", "b", "c" ].to_s     #=> "[\"a\", \"b\", \"c\"]"
+ *    a = [:foo, 'bar', 2]
+ *    a.inspect # => "[:foo, \"bar\", 2]"
+ *
+ *  Array#to_s is an alias for Array#inspect.
  */
 
 static VALUE
@@ -2137,59 +3132,88 @@ rb_ary_to_s(VALUE ary)
 
 /*
  *  call-seq:
- *     ary.to_a     -> ary
+ *    to_a -> self or new_array
  *
- *  Returns +self+.
+ *  When +self+ is an instance of \Array, returns +self+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.to_a # => [:foo, "bar", 2]
+ *
+ *  Otherwise, returns a new \Array containing the elements of +self+:
+ *
+ *    class MyArray < Array; end
+ *    a = MyArray.new(['foo', 'bar', 'two'])
+ *    a.instance_of?(Array) # => false
+ *    a.kind_of?(Array) # => true
+ *    a1 = a.to_a
+ *    a1 # => ["foo", "bar", "two"]
+ *    a1.class # => Array # Not MyArray
  *
- *  If called on a subclass of Array, converts the receiver to an Array object.
  */
 
 static VALUE
 rb_ary_to_a(VALUE ary)
 {
     if (rb_obj_class(ary) != rb_cArray) {
-	VALUE dup = rb_ary_new2(RARRAY_LEN(ary));
-	rb_ary_replace(dup, ary);
-	return dup;
+        VALUE dup = rb_ary_new2(RARRAY_LEN(ary));
+        rb_ary_replace(dup, ary);
+        return dup;
     }
     return ary;
 }
 
 /*
  *  call-seq:
- *     ary.to_h     -> hash
+ *    array.to_h -> new_hash
+ *    array.to_h {|item| ... } -> new_hash
+ *
+ *  Returns a new \Hash formed from +self+.
+ *
+ *  When a block is given, calls the block with each array element;
+ *  the block must return a 2-element \Array whose two elements
+ *  form a key-value pair in the returned \Hash:
  *
- *  Returns the result of interpreting <i>ary</i> as an array of
- *  <tt>[key, value]</tt> pairs.
+ *    a = ['foo', :bar, 1, [2, 3], {baz: 4}]
+ *    h = a.to_h {|item| [item, item] }
+ *    h # => {"foo"=>"foo", :bar=>:bar, 1=>1, [2, 3]=>[2, 3], {:baz=>4}=>{:baz=>4}}
+ *
+ *  When no block is given, +self+ must be an \Array of 2-element sub-arrays,
+ *  each sub-array is formed into a key-value pair in the new \Hash:
+ *
+ *    [].to_h # => {}
+ *    a = [['foo', 'zero'], ['bar', 'one'], ['baz', 'two']]
+ *    h = a.to_h
+ *    h # => {"foo"=>"zero", "bar"=>"one", "baz"=>"two"}
  *
- *     [[:foo, :bar], [1, 2]].to_h
- *       # => {:foo => :bar, 1 => 2}
  */
 
 static VALUE
 rb_ary_to_h(VALUE ary)
 {
     long i;
-    VALUE hash = rb_hash_new();
+    VALUE hash = rb_hash_new_with_size(RARRAY_LEN(ary));
+    int block_given = rb_block_given_p();
+
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	const VALUE elt = rb_ary_elt(ary, i);
-	const VALUE key_value_pair = rb_check_array_type(elt);
-	if (NIL_P(key_value_pair)) {
-	    rb_raise(rb_eTypeError, "wrong element type %"PRIsVALUE" at %ld (expected array)",
-		     rb_obj_class(elt), i);
-	}
-	if (RARRAY_LEN(key_value_pair) != 2) {
-	    rb_raise(rb_eArgError, "wrong array length at %ld (expected 2, was %ld)",
-		i, RARRAY_LEN(key_value_pair));
-	}
-	rb_hash_aset(hash, RARRAY_AREF(key_value_pair, 0), RARRAY_AREF(key_value_pair, 1));
+        const VALUE e = rb_ary_elt(ary, i);
+        const VALUE elt = block_given ? rb_yield_force_blockarg(e) : e;
+        const VALUE key_value_pair = rb_check_array_type(elt);
+        if (NIL_P(key_value_pair)) {
+            rb_raise(rb_eTypeError, "wrong element type %"PRIsVALUE" at %ld (expected array)",
+                     rb_obj_class(elt), i);
+        }
+        if (RARRAY_LEN(key_value_pair) != 2) {
+            rb_raise(rb_eArgError, "wrong array length at %ld (expected 2, was %ld)",
+                i, RARRAY_LEN(key_value_pair));
+        }
+        rb_hash_aset(hash, RARRAY_AREF(key_value_pair, 0), RARRAY_AREF(key_value_pair, 1));
     }
     return hash;
 }
 
 /*
  *  call-seq:
- *     ary.to_ary -> ary
+ *    array.to_ary -> self
  *
  *  Returns +self+.
  */
@@ -2204,9 +3228,9 @@ static void
 ary_reverse(VALUE *p1, VALUE *p2)
 {
     while (p1 < p2) {
-	VALUE tmp = *p1;
-	*p1++ = *p2;
-	*p2-- = tmp;
+        VALUE tmp = *p1;
+        *p1++ = *p2;
+        *p2-- = tmp;
     }
 }
 
@@ -2218,23 +3242,23 @@ rb_ary_reverse(VALUE ary)
 
     rb_ary_modify(ary);
     if (len > 1) {
-	RARRAY_PTR_USE(ary, p1, {
-	    p2 = p1 + len - 1;	/* points last item */
-	    ary_reverse(p1, p2);
-	}); /* WB: no new reference */
+        RARRAY_PTR_USE_TRANSIENT(ary, p1, {
+            p2 = p1 + len - 1;	/* points last item */
+            ary_reverse(p1, p2);
+        }); /* WB: no new reference */
     }
     return ary;
 }
 
 /*
  *  call-seq:
- *     ary.reverse!   -> ary
+ *    array.reverse! -> self
+ *
+ *  Reverses +self+ in place:
  *
- *  Reverses +self+ in place.
+ *    a = ['foo', 'bar', 'two']
+ *    a.reverse! # => ["two", "bar", "foo"]
  *
- *     a = [ "a", "b", "c" ]
- *     a.reverse!       #=> ["c", "b", "a"]
- *     a                #=> ["c", "b", "a"]
  */
 
 static VALUE
@@ -2245,12 +3269,14 @@ rb_ary_reverse_bang(VALUE ary)
 
 /*
  *  call-seq:
- *     ary.reverse    -> new_ary
+ *    array.reverse -> new_array
+ *
+ *  Returns a new \Array with the elements of +self+ in reverse order:
  *
- *  Returns a new array containing +self+'s elements in reverse order.
+ *    a = ['foo', 'bar', 'two']
+ *    a1 = a.reverse
+ *    a1 # => ["two", "bar", "foo"]
  *
- *     [ "a", "b", "c" ].reverse   #=> ["c", "b", "a"]
- *     [ 1 ].reverse               #=> [1]
  */
 
 static VALUE
@@ -2260,9 +3286,9 @@ rb_ary_reverse_m(VALUE ary)
     VALUE dup = rb_ary_new2(len);
 
     if (len > 0) {
-	const VALUE *p1 = RARRAY_CONST_PTR(ary);
-	VALUE *p2 = (VALUE *)RARRAY_CONST_PTR(dup) + len - 1;
-	do *p2-- = *p1++; while (--len > 0);
+        const VALUE *p1 = RARRAY_CONST_PTR_TRANSIENT(ary);
+        VALUE *p2 = (VALUE *)RARRAY_CONST_PTR_TRANSIENT(dup) + len - 1;
+        do *p2-- = *p1++; while (--len > 0);
     }
     ARY_SET_LEN(dup, RARRAY_LEN(ary));
     return dup;
@@ -2274,73 +3300,143 @@ rotate_count(long cnt, long len)
     return (cnt < 0) ? (len - (~cnt % len) - 1) : (cnt % len);
 }
 
+static void
+ary_rotate_ptr(VALUE *ptr, long len, long cnt)
+{
+    if (cnt == 1) {
+        VALUE tmp = *ptr;
+        memmove(ptr, ptr + 1, sizeof(VALUE)*(len - 1));
+        *(ptr + len - 1) = tmp;
+    }
+    else if (cnt == len - 1) {
+        VALUE tmp = *(ptr + len - 1);
+        memmove(ptr + 1, ptr, sizeof(VALUE)*(len - 1));
+        *ptr = tmp;
+    }
+    else {
+        --len;
+        if (cnt < len) ary_reverse(ptr + cnt, ptr + len);
+        if (--cnt > 0) ary_reverse(ptr, ptr + cnt);
+        if (len > 0) ary_reverse(ptr, ptr + len);
+    }
+}
+
 VALUE
 rb_ary_rotate(VALUE ary, long cnt)
 {
     rb_ary_modify(ary);
 
     if (cnt != 0) {
-	VALUE *ptr = RARRAY_PTR(ary);
-	long len = RARRAY_LEN(ary);
-
-	if (len > 0 && (cnt = rotate_count(cnt, len)) > 0) {
-	    --len;
-	    if (cnt < len) ary_reverse(ptr + cnt, ptr + len);
-	    if (--cnt > 0) ary_reverse(ptr, ptr + cnt);
-	    if (len > 0) ary_reverse(ptr, ptr + len);
-	    return ary;
-	}
+        long len = RARRAY_LEN(ary);
+        if (len > 1 && (cnt = rotate_count(cnt, len)) > 0) {
+            RARRAY_PTR_USE_TRANSIENT(ary, ptr, ary_rotate_ptr(ptr, len, cnt));
+            return ary;
+        }
     }
-
     return Qnil;
 }
 
 /*
  *  call-seq:
- *     ary.rotate!(count=1)   -> ary
+ *    array.rotate! -> self
+ *    array.rotate!(count) -> self
  *
- *  Rotates +self+ in place so that the element at +count+ comes first, and
- *  returns +self+.
+ *  Rotates +self+ in place by moving elements from one end to the other; returns +self+.
+ *
+ *  When no argument given, rotates the first element to the last position:
+ *
+ *    a = [:foo, 'bar', 2, 'bar']
+ *    a.rotate! # => ["bar", 2, "bar", :foo]
+ *
+ *  When given a non-negative \Integer +count+,
+ *  rotates +count+ elements from the beginning to the end:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.rotate!(2)
+ *    a # => [2, :foo, "bar"]
+ *
+ *  If +count+ is large, uses <tt>count % array.size</tt> as the count:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.rotate!(20)
+ *    a # => [2, :foo, "bar"]
+ *
+ *  If +count+ is zero, returns +self+ unmodified:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.rotate!(0)
+ *    a # => [:foo, "bar", 2]
  *
- *  If +count+ is negative then it rotates in the opposite direction, starting
- *  from the end of the array where +-1+ is the last element.
+ *  When given a negative Integer +count+, rotates in the opposite direction,
+ *  from end to beginning:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.rotate!(-2)
+ *    a # => ["bar", 2, :foo]
+ *
+ *  If +count+ is small (far from zero), uses <tt>count % array.size</tt> as the count:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.rotate!(-5)
+ *    a # => ["bar", 2, :foo]
  *
- *     a = [ "a", "b", "c", "d" ]
- *     a.rotate!        #=> ["b", "c", "d", "a"]
- *     a                #=> ["b", "c", "d", "a"]
- *     a.rotate!(2)     #=> ["d", "a", "b", "c"]
- *     a.rotate!(-3)    #=> ["a", "b", "c", "d"]
  */
 
 static VALUE
 rb_ary_rotate_bang(int argc, VALUE *argv, VALUE ary)
 {
-    long n = 1;
-
-    switch (argc) {
-      case 1: n = NUM2LONG(argv[0]);
-      case 0: break;
-      default: rb_scan_args(argc, argv, "01", NULL);
-    }
+    long n = (rb_check_arity(argc, 0, 1) ? NUM2LONG(argv[0]) : 1);
     rb_ary_rotate(ary, n);
     return ary;
 }
 
 /*
  *  call-seq:
- *     ary.rotate(count=1)    -> new_ary
+ *    array.rotate -> new_array
+ *    array.rotate(count) -> new_array
+ *
+ *  Returns a new \Array formed from +self+ with elements
+ *  rotated from one end to the other.
+ *
+ *  When no argument given, returns a new \Array that is like +self+,
+ *  except that the first element has been rotated to the last position:
+ *
+ *    a = [:foo, 'bar', 2, 'bar']
+ *    a1 = a.rotate
+ *    a1 # => ["bar", 2, "bar", :foo]
+ *
+ *  When given a non-negative \Integer +count+,
+ *  returns a new \Array with +count+ elements rotated from the beginning to the end:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a1 = a.rotate(2)
+ *    a1 # => [2, :foo, "bar"]
+ *
+ *  If +count+ is large, uses <tt>count % array.size</tt> as the count:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a1 = a.rotate(20)
+ *    a1 # => [2, :foo, "bar"]
  *
- *  Returns a new array by rotating +self+ so that the element at +count+ is
- *  the first element of the new array.
+ *  If +count+ is zero, returns a copy of +self+, unmodified:
  *
- *  If +count+ is negative then it rotates in the opposite direction, starting
- *  from the end of +self+ where +-1+ is the last element.
+ *    a = [:foo, 'bar', 2]
+ *    a1 = a.rotate(0)
+ *    a1 # => [:foo, "bar", 2]
+ *
+ *  When given a negative \Integer +count+, rotates in the opposite direction,
+ *  from end to beginning:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a1 = a.rotate(-2)
+ *    a1 # => ["bar", 2, :foo]
+ *
+ *  If +count+ is small (far from zero), uses <tt>count % array.size</tt> as the count:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a1 = a.rotate(-5)
+ *    a1 # => ["bar", 2, :foo]
  *
- *     a = [ "a", "b", "c", "d" ]
- *     a.rotate         #=> ["b", "c", "d", "a"]
- *     a                #=> ["a", "b", "c", "d"]
- *     a.rotate(2)      #=> ["c", "d", "a", "b"]
- *     a.rotate(-3)     #=> ["b", "c", "d", "a"]
  */
 
 static VALUE
@@ -2348,22 +3444,17 @@ rb_ary_rotate_m(int argc, VALUE *argv, VALUE ary)
 {
     VALUE rotated;
     const VALUE *ptr;
-    long len, cnt = 1;
-
-    switch (argc) {
-      case 1: cnt = NUM2LONG(argv[0]);
-      case 0: break;
-      default: rb_scan_args(argc, argv, "01", NULL);
-    }
+    long len;
+    long cnt = (rb_check_arity(argc, 0, 1) ? NUM2LONG(argv[0]) : 1);
 
     len = RARRAY_LEN(ary);
     rotated = rb_ary_new2(len);
     if (len > 0) {
-	cnt = rotate_count(cnt, len);
-	ptr = RARRAY_CONST_PTR(ary);
-	len -= cnt;
-	ary_memcpy(rotated, 0, len, ptr + cnt);
-	ary_memcpy(rotated, len, cnt, ptr);
+        cnt = rotate_count(cnt, len);
+        ptr = RARRAY_CONST_PTR_TRANSIENT(ary);
+        len -= cnt;
+        ary_memcpy(rotated, 0, len, ptr + cnt);
+        ary_memcpy(rotated, len, cnt, ptr);
     }
     ARY_SET_LEN(rotated, RARRAY_LEN(ary));
     return rotated;
@@ -2371,29 +3462,41 @@ rb_ary_rotate_m(int argc, VALUE *argv, VALUE ary)
 
 struct ary_sort_data {
     VALUE ary;
-    struct cmp_opt_data cmp_opt;
+    VALUE receiver;
 };
 
 static VALUE
 sort_reentered(VALUE ary)
 {
     if (RBASIC(ary)->klass) {
-	rb_raise(rb_eRuntimeError, "sort reentered");
+        rb_raise(rb_eRuntimeError, "sort reentered");
     }
     return Qnil;
 }
 
+static void
+sort_returned(struct ary_sort_data *data)
+{
+    if (rb_obj_frozen_p(data->receiver)) {
+        rb_raise(rb_eFrozenError, "array frozen during sort");
+    }
+    sort_reentered(data->ary);
+}
+
 static int
 sort_1(const void *ap, const void *bp, void *dummy)
 {
     struct ary_sort_data *data = dummy;
     VALUE retval = sort_reentered(data->ary);
     VALUE a = *(const VALUE *)ap, b = *(const VALUE *)bp;
+    VALUE args[2];
     int n;
 
-    retval = rb_yield_values(2, a, b);
+    args[0] = a;
+    args[1] = b;
+    retval = rb_yield_values2(2, args);
     n = rb_cmpint(retval, a, b);
-    sort_reentered(data->ary);
+    sort_returned(data);
     return n;
 }
 
@@ -2405,41 +3508,64 @@ sort_2(const void *ap, const void *bp, void *dummy)
     VALUE a = *(const VALUE *)ap, b = *(const VALUE *)bp;
     int n;
 
-    if (FIXNUM_P(a) && FIXNUM_P(b) && CMP_OPTIMIZABLE(data->cmp_opt, Fixnum)) {
-	if ((long)a > (long)b) return 1;
-	if ((long)a < (long)b) return -1;
-	return 0;
+    if (FIXNUM_P(a) && FIXNUM_P(b) && CMP_OPTIMIZABLE(INTEGER)) {
+        if ((long)a > (long)b) return 1;
+        if ((long)a < (long)b) return -1;
+        return 0;
     }
-    if (STRING_P(a) && STRING_P(b) && CMP_OPTIMIZABLE(data->cmp_opt, String)) {
-	return rb_str_cmp(a, b);
+    if (STRING_P(a) && STRING_P(b) && CMP_OPTIMIZABLE(STRING)) {
+        return rb_str_cmp(a, b);
+    }
+    if (RB_FLOAT_TYPE_P(a) && CMP_OPTIMIZABLE(FLOAT)) {
+        return rb_float_cmp(a, b);
     }
 
     retval = rb_funcallv(a, id_cmp, 1, &b);
     n = rb_cmpint(retval, a, b);
-    sort_reentered(data->ary);
+    sort_returned(data);
 
     return n;
 }
 
 /*
  *  call-seq:
- *     ary.sort!                   -> ary
- *     ary.sort! { |a, b| block }  -> ary
+ *    array.sort! -> self
+ *    array.sort! {|a, b| ... } -> self
+ *
+ *  Returns +self+ with its elements sorted in place.
+ *
+ *  With no block, compares elements using operator <tt><=></tt>
+ *  (see Comparable):
+ *
+ *    a = 'abcde'.split('').shuffle
+ *    a # => ["e", "b", "d", "a", "c"]
+ *    a.sort!
+ *    a # => ["a", "b", "c", "d", "e"]
  *
- *  Sorts +self+ in place.
+ *  With a block, calls the block with each element pair;
+ *  for each element pair +a+ and +b+, the block should return an integer:
  *
- *  Comparisons for the sort will be done using the <code><=></code> operator
- *  or using an optional code block.
+ *  - Negative when +b+ is to follow +a+.
+ *  - Zero when +a+ and +b+ are equivalent.
+ *  - Positive when +a+ is to follow +b+.
  *
- *  The block must implement a comparison between +a+ and +b+ and return
- *  an integer less than 0 when +b+ follows +a+, +0+ when +a+ and +b+
- *  are equivalent, or an integer greater than 0 when +a+ follows +b+.
+ *  Example:
  *
- *  See also Enumerable#sort_by.
+ *    a = 'abcde'.split('').shuffle
+ *    a # => ["e", "b", "d", "a", "c"]
+ *    a.sort! {|a, b| a <=> b }
+ *    a # => ["a", "b", "c", "d", "e"]
+ *    a.sort! {|a, b| b <=> a }
+ *    a # => ["e", "d", "c", "b", "a"]
+ *
+ *  When the block returns zero, the order for +a+ and +b+ is indeterminate,
+ *  and may be unstable:
+ *
+ *    a = 'abcde'.split('').shuffle
+ *    a # => ["e", "b", "d", "a", "c"]
+ *    a.sort! {|a, b| 0 }
+ *    a # => ["d", "e", "c", "a", "b"]
  *
- *     a = [ "d", "a", "e", "c", "b" ]
- *     a.sort!                    #=> ["a", "b", "c", "d", "e"]
- *     a.sort! { |x,y| y <=> x }  #=> ["e", "d", "c", "b", "a"]
  */
 
 VALUE
@@ -2448,25 +3574,23 @@ rb_ary_sort_bang(VALUE ary)
     rb_ary_modify(ary);
     assert(!ARY_SHARED_P(ary));
     if (RARRAY_LEN(ary) > 1) {
-	VALUE tmp = ary_make_substitution(ary); /* only ary refers tmp */
-	struct ary_sort_data data;
-	long len = RARRAY_LEN(ary);
-
-	RBASIC_CLEAR_CLASS(tmp);
-	data.ary = tmp;
-	data.cmp_opt.opt_methods = 0;
-	data.cmp_opt.opt_inited = 0;
-	RARRAY_PTR_USE(tmp, ptr, {
-	    ruby_qsort(ptr, len, sizeof(VALUE),
-		       rb_block_given_p()?sort_1:sort_2, &data);
-	}); /* WB: no new reference */
-	rb_ary_modify(ary);
+        VALUE tmp = ary_make_substitution(ary); /* only ary refers tmp */
+        struct ary_sort_data data;
+        long len = RARRAY_LEN(ary);
+        RBASIC_CLEAR_CLASS(tmp);
+        data.ary = tmp;
+        data.receiver = ary;
+        RARRAY_PTR_USE(tmp, ptr, {
+            ruby_qsort(ptr, len, sizeof(VALUE),
+                       rb_block_given_p()?sort_1:sort_2, &data);
+        }); /* WB: no new reference */
+        rb_ary_modify(ary);
         if (ARY_EMBED_P(tmp)) {
             if (ARY_SHARED_P(ary)) { /* ary might be destructively operated in the given block */
                 rb_ary_unshare(ary);
-		FL_SET_EMBED(ary);
+                FL_SET_EMBED(ary);
             }
-	    ary_memcpy(ary, 0, ARY_EMBED_LEN(tmp), ARY_EMBED_PTR(tmp));
+            ary_memcpy(ary, 0, ARY_EMBED_LEN(tmp), ARY_EMBED_PTR(tmp));
             ARY_SET_LEN(ary, ARY_EMBED_LEN(tmp));
         }
         else {
@@ -2484,44 +3608,65 @@ rb_ary_sort_bang(VALUE ary)
                     rb_ary_unshare(ary);
                 }
                 else {
-		    ruby_sized_xfree((void *)ARY_HEAP_PTR(ary), ARY_HEAP_SIZE(ary));
+                    ary_heap_free(ary);
                 }
-                ARY_SET_PTR(ary, RARRAY_CONST_PTR(tmp));
+                ARY_SET_PTR(ary, ARY_HEAP_PTR(tmp));
                 ARY_SET_HEAP_LEN(ary, len);
-                ARY_SET_CAPA(ary, RARRAY_LEN(tmp));
+                ARY_SET_CAPA(ary, ARY_HEAP_LEN(tmp));
             }
             /* tmp was lost ownership for the ptr */
             FL_UNSET(tmp, FL_FREEZE);
             FL_SET_EMBED(tmp);
             ARY_SET_EMBED_LEN(tmp, 0);
             FL_SET(tmp, FL_FREEZE);
-	}
+        }
         /* tmp will be GC'ed. */
         RBASIC_SET_CLASS_RAW(tmp, rb_cArray); /* rb_cArray must be marked */
     }
+    ary_verify(ary);
     return ary;
 }
 
 /*
  *  call-seq:
- *     ary.sort                   -> new_ary
- *     ary.sort { |a, b| block }  -> new_ary
+ *    array.sort -> new_array
+ *    array.sort {|a, b| ... } -> new_array
+ *
+ *  Returns a new \Array whose elements are those from +self+, sorted.
+ *
+ *  With no block, compares elements using operator <tt><=></tt>
+ *  (see Comparable):
  *
- *  Returns a new array created by sorting +self+.
+ *    a = 'abcde'.split('').shuffle
+ *    a # => ["e", "b", "d", "a", "c"]
+ *    a1 = a.sort
+ *    a1 # => ["a", "b", "c", "d", "e"]
  *
- *  Comparisons for the sort will be done using the <code><=></code> operator
- *  or using an optional code block.
+ *  With a block, calls the block with each element pair;
+ *  for each element pair +a+ and +b+, the block should return an integer:
  *
- *  The block must implement a comparison between +a+ and +b+ and return
- *  an integer less than 0 when +b+ follows +a+, +0+ when +a+ and +b+
- *  are equivalent, or an integer greater than 0 when +a+ follows +b+.
+ *  - Negative when +b+ is to follow +a+.
+ *  - Zero when +a+ and +b+ are equivalent.
+ *  - Positive when +a+ is to follow +b+.
  *
+ *  Example:
  *
- *  See also Enumerable#sort_by.
+ *    a = 'abcde'.split('').shuffle
+ *    a # => ["e", "b", "d", "a", "c"]
+ *    a1 = a.sort {|a, b| a <=> b }
+ *    a1 # => ["a", "b", "c", "d", "e"]
+ *    a2 = a.sort {|a, b| b <=> a }
+ *    a2 # => ["e", "d", "c", "b", "a"]
  *
- *     a = [ "d", "a", "e", "c", "b" ]
- *     a.sort                    #=> ["a", "b", "c", "d", "e"]
- *     a.sort { |x,y| y <=> x }  #=> ["e", "d", "c", "b", "a"]
+ *  When the block returns zero, the order for +a+ and +b+ is indeterminate,
+ *  and may be unstable:
+ *
+ *    a = 'abcde'.split('').shuffle
+ *    a # => ["e", "b", "d", "a", "c"]
+ *    a1 = a.sort {|a, b| 0 }
+ *    a1 # =>  ["c", "e", "b", "d", "a"]
+ *
+ *  Related: Enumerable#sort_by.
  */
 
 VALUE
@@ -2536,55 +3681,12 @@ static VALUE rb_ary_bsearch_index(VALUE ary);
 
 /*
  *  call-seq:
- *     ary.bsearch {|x| block }  -> elem
- *
- *  By using binary search, finds a value from this array which meets
- *  the given condition in O(log n) where n is the size of the array.
- *
- *  You can use this method in two use cases: a find-minimum mode and
- *  a find-any mode.  In either case, the elements of the array must be
- *  monotone (or sorted) with respect to the block.
- *
- *  In find-minimum mode (this is a good choice for typical use case),
- *  the block must return true or false, and there must be an index i
- *  (0 <= i <= ary.size) so that:
- *
- *  - the block returns false for any element whose index is less than
- *    i, and
- *  - the block returns true for any element whose index is greater
- *    than or equal to i.
- *
- *  This method returns the i-th element.  If i is equal to ary.size,
- *  it returns nil.
- *
- *     ary = [0, 4, 7, 10, 12]
- *     ary.bsearch {|x| x >=   4 } #=> 4
- *     ary.bsearch {|x| x >=   6 } #=> 7
- *     ary.bsearch {|x| x >=  -1 } #=> 0
- *     ary.bsearch {|x| x >= 100 } #=> nil
- *
- *  In find-any mode (this behaves like libc's bsearch(3)), the block
- *  must return a number, and there must be two indices i and j
- *  (0 <= i <= j <= ary.size) so that:
- *
- *  - the block returns a positive number for ary[k] if 0 <= k < i,
- *  - the block returns zero for ary[k] if i <= k < j, and
- *  - the block returns a negative number for ary[k] if
- *    j <= k < ary.size.
- *
- *  Under this condition, this method returns any element whose index
- *  is within i...j.  If i is equal to j (i.e., there is no element
- *  that satisfies the block), this method returns nil.
- *
- *     ary = [0, 4, 7, 10, 12]
- *     # try to find v such that 4 <= v < 8
- *     ary.bsearch {|x| 1 - x / 4 } #=> 4 or 7
- *     # try to find v such that 8 <= v < 10
- *     ary.bsearch {|x| 4 - x / 2 } #=> nil
- *
- *  You must not mix the two modes at a time; the block must always
- *  return either true/false, or always return a number.  It is
- *  undefined which value is actually picked up at each iteration.
+ *    array.bsearch {|element| ... } -> object
+ *    array.bsearch -> new_enumerator
+ *
+ *  Returns an element from +self+ selected by a binary search.
+ *
+ *  See {Binary Searching}[rdoc-ref:bsearch.rdoc].
  */
 
 static VALUE
@@ -2593,22 +3695,18 @@ rb_ary_bsearch(VALUE ary)
     VALUE index_result = rb_ary_bsearch_index(ary);
 
     if (FIXNUM_P(index_result)) {
-	return rb_ary_entry(ary, FIX2LONG(index_result));
+        return rb_ary_entry(ary, FIX2LONG(index_result));
     }
     return index_result;
 }
 
 /*
  *  call-seq:
- *     ary.bsearch_index {|x| block }  -> int or nil
+ *    array.bsearch_index {|element| ... } -> integer or nil
+ *    array.bsearch_index -> new_enumerator
  *
- *  By using binary search, finds an index of a value from this array which
- *  meets the given condition in O(log n) where n is the size of the array.
- *
- *  It supports two modes, depending on the nature of the block and they are
- *  exactly the same as in the case of #bsearch method with the only difference
- *  being that this method returns the index of the element instead of the
- *  element itself. For more details consult the documentation for #bsearch.
+ *  Searches +self+ as described at method #bsearch,
+ *  but returns the _index_ of the found element instead of the element itself.
  */
 
 static VALUE
@@ -2620,39 +3718,39 @@ rb_ary_bsearch_index(VALUE ary)
 
     RETURN_ENUMERATOR(ary, 0, 0);
     while (low < high) {
-	mid = low + ((high - low) / 2);
-	val = rb_ary_entry(ary, mid);
-	v = rb_yield(val);
-	if (FIXNUM_P(v)) {
-	    if (v == INT2FIX(0)) return INT2FIX(mid);
-	    smaller = (SIGNED_VALUE)v < 0; /* Fixnum preserves its sign-bit */
-	}
-	else if (v == Qtrue) {
-	    satisfied = 1;
-	    smaller = 1;
-	}
-	else if (v == Qfalse || v == Qnil) {
-	    smaller = 0;
-	}
-	else if (rb_obj_is_kind_of(v, rb_cNumeric)) {
-	    const VALUE zero = INT2FIX(0);
-	    switch (rb_cmpint(rb_funcallv(v, id_cmp, 1, &zero), v, zero)) {
-	      case 0: return INT2FIX(mid);
-	      case 1: smaller = 1; break;
-	      case -1: smaller = 0;
-	    }
-	}
-	else {
-	    rb_raise(rb_eTypeError, "wrong argument type %"PRIsVALUE
-		     " (must be numeric, true, false or nil)",
-		     rb_obj_class(v));
-	}
-	if (smaller) {
-	    high = mid;
-	}
-	else {
-	    low = mid + 1;
-	}
+        mid = low + ((high - low) / 2);
+        val = rb_ary_entry(ary, mid);
+        v = rb_yield(val);
+        if (FIXNUM_P(v)) {
+            if (v == INT2FIX(0)) return INT2FIX(mid);
+            smaller = (SIGNED_VALUE)v < 0; /* Fixnum preserves its sign-bit */
+        }
+        else if (v == Qtrue) {
+            satisfied = 1;
+            smaller = 1;
+        }
+        else if (!RTEST(v)) {
+            smaller = 0;
+        }
+        else if (rb_obj_is_kind_of(v, rb_cNumeric)) {
+            const VALUE zero = INT2FIX(0);
+            switch (rb_cmpint(rb_funcallv(v, id_cmp, 1, &zero), v, zero)) {
+              case 0: return INT2FIX(mid);
+              case 1: smaller = 0; break;
+              case -1: smaller = 1;
+            }
+        }
+        else {
+            rb_raise(rb_eTypeError, "wrong argument type %"PRIsVALUE
+                     " (must be numeric, true, false or nil)",
+                     rb_obj_class(v));
+        }
+        if (smaller) {
+            high = mid;
+        }
+        else {
+            low = mid + 1;
+        }
     }
     if (!satisfied) return Qnil;
     return INT2FIX(low);
@@ -2667,13 +3765,27 @@ sort_by_i(RB_BLOCK_CALL_FUNC_ARGLIST(i, dummy))
 
 /*
  *  call-seq:
- *     ary.sort_by! { |obj| block }    -> ary
- *     ary.sort_by!                    -> Enumerator
+ *    array.sort_by! {|element| ... } -> self
+ *    array.sort_by! -> new_enumerator
+ *
+ *  Sorts the elements of +self+ in place,
+ *  using an ordering determined by the block; returns self.
+ *
+ *  Calls the block with each successive element;
+ *  sorts elements based on the values returned from the block.
+ *
+ *  For duplicates returned by the block, the ordering is indeterminate, and may be unstable.
  *
- *  Sorts +self+ in place using a set of keys generated by mapping the
- *  values in +self+ through the given block.
+ *  This example sorts strings based on their sizes:
  *
- *  If no block is given, an Enumerator is returned instead.
+ *    a = ['aaaa', 'bbb', 'cc', 'd']
+ *    a.sort_by! {|element| element.size }
+ *    a # => ["d", "cc", "bbb", "aaaa"]
+ *
+ *  Returns a new \Enumerator if no block given:
+ *
+ *    a = ['aaaa', 'bbb', 'cc', 'd']
+ *    a.sort_by! # => #<Enumerator: ["aaaa", "bbb", "cc", "d"]:sort_by!>
  *
  */
 
@@ -2692,23 +3804,22 @@ rb_ary_sort_by_bang(VALUE ary)
 
 /*
  *  call-seq:
- *     ary.collect { |item| block }  -> new_ary
- *     ary.map     { |item| block }  -> new_ary
- *     ary.collect                   -> Enumerator
- *     ary.map                       -> Enumerator
- *
- *  Invokes the given block once for each element of +self+.
+ *    array.map {|element| ... } -> new_array
+ *    array.map -> new_enumerator
  *
- *  Creates a new array containing the values returned by the block.
+ *  Calls the block, if given, with each element of +self+;
+ *  returns a new \Array whose elements are the return values from the block:
  *
- *  See also Enumerable#collect.
+ *    a = [:foo, 'bar', 2]
+ *    a1 = a.map {|element| element.class }
+ *    a1 # => [Symbol, String, Integer]
  *
- *  If no block is given, an Enumerator is returned instead.
+ *  Returns a new \Enumerator if no block given:
+ *    a = [:foo, 'bar', 2]
+ *    a1 = a.map
+ *    a1 # => #<Enumerator: [:foo, "bar", 2]:map>
  *
- *     a = [ "a", "b", "c", "d" ]
- *     a.collect { |x| x + "!" }         #=> ["a!", "b!", "c!", "d!"]
- *     a.map.with_index { |x, i| x * i } #=> ["", "b", "cc", "ddd"]
- *     a                                 #=> ["a", "b", "c", "d"]
+ *  Array#collect is an alias for Array#map.
  */
 
 static VALUE
@@ -2720,7 +3831,7 @@ rb_ary_collect(VALUE ary)
     RETURN_SIZED_ENUMERATOR(ary, 0, 0, ary_enum_length);
     collect = rb_ary_new2(RARRAY_LEN(ary));
     for (i = 0; i < RARRAY_LEN(ary); i++) {
-	rb_ary_push(collect, rb_yield(RARRAY_AREF(ary, i)));
+        rb_ary_push(collect, rb_yield(RARRAY_AREF(ary, i)));
     }
     return collect;
 }
@@ -2728,23 +3839,22 @@ rb_ary_collect(VALUE ary)
 
 /*
  *  call-seq:
- *     ary.collect! {|item| block }   -> ary
- *     ary.map!     {|item| block }   -> ary
- *     ary.collect!                   -> Enumerator
- *     ary.map!                       -> Enumerator
+ *    array.map! {|element| ... } -> self
+ *    array.map! -> new_enumerator
  *
- *  Invokes the given block once for each element of +self+, replacing the
- *  element with the value returned by the block.
+ *  Calls the block, if given, with each element;
+ *  replaces the element with the block's return value:
  *
- *  See also Enumerable#collect.
+ *    a = [:foo, 'bar', 2]
+ *    a.map! { |element| element.class } # => [Symbol, String, Integer]
  *
- *  If no block is given, an Enumerator is returned instead.
+ *  Returns a new \Enumerator if no block given:
  *
- *     a = [ "a", "b", "c", "d" ]
- *     a.map! {|x| x + "!" }
- *     a #=>  [ "a!", "b!", "c!", "d!" ]
- *     a.collect!.with_index {|x, i| x[0...i] }
- *     a #=>  ["", "b", "c!", "d!"]
+ *    a = [:foo, 'bar', 2]
+ *    a1 = a.map!
+ *    a1 # => #<Enumerator: [:foo, "bar", 2]:map!>
+ *
+ *  Array#collect! is an alias for Array#map!.
  */
 
 static VALUE
@@ -2755,7 +3865,7 @@ rb_ary_collect_bang(VALUE ary)
     RETURN_SIZED_ENUMERATOR(ary, 0, 0, ary_enum_length);
     rb_ary_modify(ary);
     for (i = 0; i < RARRAY_LEN(ary); i++) {
-	rb_ary_store(ary, i, rb_yield(RARRAY_AREF(ary, i)));
+        rb_ary_store(ary, i, rb_yield(RARRAY_AREF(ary, i)));
     }
     return ary;
 }
@@ -2767,66 +3877,128 @@ rb_get_values_at(VALUE obj, long olen, int argc, const VALUE *argv, VALUE (*func
     long beg, len, i, j;
 
     for (i=0; i<argc; i++) {
-	if (FIXNUM_P(argv[i])) {
-	    rb_ary_push(result, (*func)(obj, FIX2LONG(argv[i])));
-	    continue;
-	}
-	/* check if idx is Range */
-	if (rb_range_beg_len(argv[i], &beg, &len, olen, 1)) {
-	    long end = olen < beg+len ? olen : beg+len;
-	    for (j = beg; j < end; j++) {
-		rb_ary_push(result, (*func)(obj, j));
-	    }
-	    if (beg + len > j)
-		rb_ary_resize(result, RARRAY_LEN(result) + (beg + len) - j);
-	    continue;
-	}
-	rb_ary_push(result, (*func)(obj, NUM2LONG(argv[i])));
+        if (FIXNUM_P(argv[i])) {
+            rb_ary_push(result, (*func)(obj, FIX2LONG(argv[i])));
+            continue;
+        }
+        /* check if idx is Range */
+        if (rb_range_beg_len(argv[i], &beg, &len, olen, 1)) {
+            long end = olen < beg+len ? olen : beg+len;
+            for (j = beg; j < end; j++) {
+                rb_ary_push(result, (*func)(obj, j));
+            }
+            if (beg + len > j)
+                rb_ary_resize(result, RARRAY_LEN(result) + (beg + len) - j);
+            continue;
+        }
+        rb_ary_push(result, (*func)(obj, NUM2LONG(argv[i])));
     }
     return result;
 }
 
+static VALUE
+append_values_at_single(VALUE result, VALUE ary, long olen, VALUE idx)
+{
+    long beg, len;
+    if (FIXNUM_P(idx)) {
+        beg = FIX2LONG(idx);
+    }
+    /* check if idx is Range */
+    else if (rb_range_beg_len(idx, &beg, &len, olen, 1)) {
+        if (len > 0) {
+            const VALUE *const src = RARRAY_CONST_PTR_TRANSIENT(ary);
+            const long end = beg + len;
+            const long prevlen = RARRAY_LEN(result);
+            if (beg < olen) {
+                rb_ary_cat(result, src + beg, end > olen ? olen-beg : len);
+            }
+            if (end > olen) {
+                rb_ary_store(result, prevlen + len - 1, Qnil);
+            }
+        }
+        return result;
+    }
+    else {
+        beg = NUM2LONG(idx);
+    }
+    return rb_ary_push(result, rb_ary_entry(ary, beg));
+}
+
 /*
  *  call-seq:
- *     ary.values_at(selector, ...)  -> new_ary
+ *    array.values_at(*indexes) -> new_array
+ *
+ *  Returns a new \Array whose elements are the elements
+ *  of +self+ at the given \Integer or \Range +indexes+.
+ *
+ *  For each positive +index+, returns the element at offset +index+:
  *
- *  Returns an array containing the elements in +self+ corresponding to the
- *  given +selector+(s).
+ *    a = [:foo, 'bar', 2]
+ *    a.values_at(0, 2) # => [:foo, 2]
+ *    a.values_at(0..1) # => [:foo, "bar"]
  *
- *  The selectors may be either integer indices or ranges.
+ *  The given +indexes+ may be in any order, and may repeat:
  *
- *  See also Array#select.
+ *    a = [:foo, 'bar', 2]
+ *    a.values_at(2, 0, 1, 0, 2) # => [2, :foo, "bar", :foo, 2]
+ *    a.values_at(1, 0..2) # => ["bar", :foo, "bar", 2]
+ *
+ *  Assigns +nil+ for an +index+ that is too large:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.values_at(0, 3, 1, 3) # => [:foo, nil, "bar", nil]
+ *
+ *  Returns a new empty \Array if no arguments given.
+ *
+ *  For each negative +index+, counts backward from the end of the array:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.values_at(-1, -3) # => [2, :foo]
+ *
+ *  Assigns +nil+ for an +index+ that is too small:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.values_at(0, -5, 1, -6, 2) # => [:foo, nil, "bar", nil, 2]
+ *
+ *  The given +indexes+ may have a mixture of signs:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.values_at(0, -2, 1, -1) # => [:foo, "bar", "bar", 2]
  *
- *     a = %w{ a b c d e f }
- *     a.values_at(1, 3, 5)          # => ["b", "d", "f"]
- *     a.values_at(1, 3, 5, 7)       # => ["b", "d", "f", nil]
- *     a.values_at(-1, -2, -2, -7)   # => ["f", "e", "e", nil]
- *     a.values_at(4..6, 3...6)      # => ["e", "f", nil, "d", "e", "f"]
  */
 
 static VALUE
 rb_ary_values_at(int argc, VALUE *argv, VALUE ary)
 {
-    return rb_get_values_at(ary, RARRAY_LEN(ary), argc, argv, rb_ary_entry);
+    long i, olen = RARRAY_LEN(ary);
+    VALUE result = rb_ary_new_capa(argc);
+    for (i = 0; i < argc; ++i) {
+        append_values_at_single(result, ary, olen, argv[i]);
+    }
+    RB_GC_GUARD(ary);
+    return result;
 }
 
 
 /*
  *  call-seq:
- *     ary.select { |item| block } -> new_ary
- *     ary.select                  -> Enumerator
+ *    array.select {|element| ... } -> new_array
+ *    array.select -> new_enumerator
  *
- *  Returns a new array containing all elements of +ary+
- *  for which the given +block+ returns a true value.
+ *  Calls the block, if given, with each element of +self+;
+ *  returns a new \Array containing those elements of +self+
+ *  for which the block returns a truthy value:
  *
- *  If no block is given, an Enumerator is returned instead.
+ *    a = [:foo, 'bar', 2, :bam]
+ *    a1 = a.select {|element| element.to_s.start_with?('b') }
+ *    a1 # => ["bar", :bam]
  *
- *     [1,2,3,4,5].select { |num|  num.even?  }   #=> [2, 4]
+ *  Returns a new \Enumerator if no block given:
  *
- *     a = %w{ a b c d e f }
- *     a.select { |v| v =~ /[aeiou]/ }  #=> ["a", "e"]
+ *    a = [:foo, 'bar', 2, :bam]
+ *    a.select # => #<Enumerator: [:foo, "bar", 2, :bam]:select>
  *
- *  See also Enumerable#select.
+ *  Array#filter is an alias for Array#select.
  */
 
 static VALUE
@@ -2838,9 +4010,9 @@ rb_ary_select(VALUE ary)
     RETURN_SIZED_ENUMERATOR(ary, 0, 0, ary_enum_length);
     result = rb_ary_new2(RARRAY_LEN(ary));
     for (i = 0; i < RARRAY_LEN(ary); i++) {
-	if (RTEST(rb_yield(RARRAY_AREF(ary, i)))) {
-	    rb_ary_push(result, rb_ary_elt(ary, i));
-	}
+        if (RTEST(rb_yield(RARRAY_AREF(ary, i)))) {
+            rb_ary_push(result, rb_ary_elt(ary, i));
+        }
     }
     return result;
 }
@@ -2858,12 +4030,12 @@ select_bang_i(VALUE a)
     long i1, i2;
 
     for (i1 = i2 = 0; i1 < RARRAY_LEN(ary); arg->len[0] = ++i1) {
-	VALUE v = RARRAY_AREF(ary, i1);
-	if (!RTEST(rb_yield(v))) continue;
-	if (i1 != i2) {
-	    rb_ary_store(ary, i2, v);
-	}
-	arg->len[1] = ++i2;
+        VALUE v = RARRAY_AREF(ary, i1);
+        if (!RTEST(rb_yield(v))) continue;
+        if (i1 != i2) {
+            rb_ary_store(ary, i2, v);
+        }
+        arg->len[1] = ++i2;
     }
     return (i1 == i2) ? Qnil : ary;
 }
@@ -2876,33 +4048,41 @@ select_bang_ensure(VALUE a)
     long len = RARRAY_LEN(ary);
     long i1 = arg->len[0], i2 = arg->len[1];
 
-    if (i2 < i1) {
-	if (i1 < len) {
-	    RARRAY_PTR_USE(ary, ptr, {
-		    MEMMOVE(ptr + i2, ptr + i1, VALUE, len - i1);
-		});
-	}
-	ARY_SET_LEN(ary, len - i1 + i2);
+    if (i2 < len && i2 < i1) {
+        long tail = 0;
+        rb_ary_modify(ary);
+        if (i1 < len) {
+            tail = len - i1;
+            RARRAY_PTR_USE_TRANSIENT(ary, ptr, {
+                    MEMMOVE(ptr + i2, ptr + i1, VALUE, tail);
+                });
+        }
+        ARY_SET_LEN(ary, i2 + tail);
     }
     return ary;
 }
 
 /*
  *  call-seq:
- *     ary.select!  {|item| block } -> ary or nil
- *     ary.select!                  -> Enumerator
+ *    array.select! {|element| ... } -> self or nil
+ *    array.select! -> new_enumerator
+ *
+ *  Calls the block, if given  with each element of +self+;
+ *  removes from +self+ those elements for which the block returns +false+ or +nil+.
  *
- *  Invokes the given block passing in successive elements from +self+,
- *  deleting elements for which the block returns a +false+ value.
+ *  Returns +self+ if any elements were removed:
  *
- *  The array may not be changed instantly every time the block is called.
+ *    a = [:foo, 'bar', 2, :bam]
+ *    a.select! {|element| element.to_s.start_with?('b') } # => ["bar", :bam]
  *
- *  If changes were made, it will return +self+, otherwise it returns +nil+.
+ *  Returns +nil+ if no elements were removed.
  *
- *  See also Array#keep_if
+ *  Returns a new \Enumerator if no block given:
  *
- *  If no block is given, an Enumerator is returned instead.
+ *    a = [:foo, 'bar', 2, :bam]
+ *    a.select! # => #<Enumerator: [:foo, "bar", 2, :bam]:select!>
  *
+ *  Array#filter! is an alias for Array#select!.
  */
 
 static VALUE
@@ -2920,18 +4100,20 @@ rb_ary_select_bang(VALUE ary)
 
 /*
  *  call-seq:
- *     ary.keep_if { |item| block } -> ary
- *     ary.keep_if                  -> Enumerator
+ *    array.keep_if {|element| ... } -> self
+ *    array.keep_if -> new_enumeration
  *
- *  Deletes every element of +self+ for which the given block evaluates to
- *  +false+.
+ *  Retains those elements for which the block returns a truthy value;
+ *  deletes all other elements; returns +self+:
  *
- *  See also Array#select!
+ *    a = [:foo, 'bar', 2, :bam]
+ *    a.keep_if {|element| element.to_s.start_with?('b') } # => ["bar", :bam]
  *
- *  If no block is given, an Enumerator is returned instead.
+ *  Returns a new \Enumerator if no block given:
+ *
+ *    a = [:foo, 'bar', 2, :bam]
+ *    a.keep_if # => #<Enumerator: [:foo, "bar", 2, :bam]:keep_if>
  *
- *     a = %w{ a b c d e f }
- *     a.keep_if { |v| v =~ /[aeiou]/ }  #=> ["a", "e"]
  */
 
 static VALUE
@@ -2947,32 +4129,48 @@ ary_resize_smaller(VALUE ary, long len)
 {
     rb_ary_modify(ary);
     if (RARRAY_LEN(ary) > len) {
-	ARY_SET_LEN(ary, len);
-	if (len * 2 < ARY_CAPA(ary) &&
-	    ARY_CAPA(ary) > ARY_DEFAULT_SIZE) {
-	    ary_resize_capa(ary, len * 2);
-	}
+        ARY_SET_LEN(ary, len);
+        if (len * 2 < ARY_CAPA(ary) &&
+            ARY_CAPA(ary) > ARY_DEFAULT_SIZE) {
+            ary_resize_capa(ary, len * 2);
+        }
     }
 }
 
 /*
  *  call-seq:
- *     ary.delete(obj)            -> item or nil
- *     ary.delete(obj) { block }  -> item or result of block
+ *    array.delete(obj) -> deleted_object
+ *    array.delete(obj) {|nosuch| ... } -> deleted_object or block_return
+ *
+ *  Removes zero or more elements from +self+.
+ *
+ *  When no block is given,
+ *  removes from +self+ each element +ele+ such that <tt>ele == obj</tt>;
+ *  returns the last deleted element:
+ *
+ *    s1 = 'bar'; s2 = 'bar'
+ *    a = [:foo, s1, 2, s2]
+ *    a.delete('bar') # => "bar"
+ *    a # => [:foo, 2]
  *
- *  Deletes all items from +self+ that are equal to +obj+.
+ *  Returns +nil+ if no elements removed.
  *
- *  Returns the last deleted item, or +nil+ if no matching item is found.
+ *  When a block is given,
+ *  removes from +self+ each element +ele+ such that <tt>ele == obj</tt>.
  *
- *  If the optional code block is given, the result of the block is returned if
- *  the item is not found.  (To remove +nil+ elements and get an informative
- *  return value, use Array#compact!)
+ *  If any such elements are found, ignores the block
+ *  and returns the last deleted element:
+ *
+ *    s1 = 'bar'; s2 = 'bar'
+ *    a = [:foo, s1, 2, s2]
+ *    deleted_obj = a.delete('bar') {|obj| fail 'Cannot happen' }
+ *    a # => [:foo, 2]
+ *
+ *  If no such elements are found, returns the block's return value:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.delete(:nosuch) {|obj| "#{obj} not found" } # => "nosuch not found"
  *
- *     a = [ "a", "b", "b", "b", "c" ]
- *     a.delete("b")                   #=> "b"
- *     a                               #=> ["a", "c"]
- *     a.delete("z")                   #=> nil
- *     a.delete("z") { "not found" }   #=> "not found"
  */
 
 VALUE
@@ -2982,26 +4180,27 @@ rb_ary_delete(VALUE ary, VALUE item)
     long i1, i2;
 
     for (i1 = i2 = 0; i1 < RARRAY_LEN(ary); i1++) {
-	VALUE e = RARRAY_AREF(ary, i1);
+        VALUE e = RARRAY_AREF(ary, i1);
 
-	if (rb_equal(e, item)) {
-	    v = e;
-	    continue;
-	}
-	if (i1 != i2) {
-	    rb_ary_store(ary, i2, e);
-	}
-	i2++;
+        if (rb_equal(e, item)) {
+            v = e;
+            continue;
+        }
+        if (i1 != i2) {
+            rb_ary_store(ary, i2, e);
+        }
+        i2++;
     }
     if (RARRAY_LEN(ary) == i2) {
-	if (rb_block_given_p()) {
-	    return rb_yield(item);
-	}
-	return Qnil;
+        if (rb_block_given_p()) {
+            return rb_yield(item);
+        }
+        return Qnil;
     }
 
     ary_resize_smaller(ary, i2);
 
+    ary_verify(ary);
     return v;
 }
 
@@ -3011,18 +4210,18 @@ rb_ary_delete_same(VALUE ary, VALUE item)
     long i1, i2;
 
     for (i1 = i2 = 0; i1 < RARRAY_LEN(ary); i1++) {
-	VALUE e = RARRAY_AREF(ary, i1);
+        VALUE e = RARRAY_AREF(ary, i1);
 
-	if (e == item) {
-	    continue;
-	}
-	if (i1 != i2) {
-	    rb_ary_store(ary, i2, e);
-	}
-	i2++;
+        if (e == item) {
+            continue;
+        }
+        if (i1 != i2) {
+            rb_ary_store(ary, i2, e);
+        }
+        i2++;
     }
     if (RARRAY_LEN(ary) == i2) {
-	return;
+        return;
     }
 
     ary_resize_smaller(ary, i2);
@@ -3036,33 +4235,41 @@ rb_ary_delete_at(VALUE ary, long pos)
 
     if (pos >= len) return Qnil;
     if (pos < 0) {
-	pos += len;
-	if (pos < 0) return Qnil;
+        pos += len;
+        if (pos < 0) return Qnil;
     }
 
     rb_ary_modify(ary);
     del = RARRAY_AREF(ary, pos);
-    RARRAY_PTR_USE(ary, ptr, {
-	MEMMOVE(ptr+pos, ptr+pos+1, VALUE, len-pos-1);
+    RARRAY_PTR_USE_TRANSIENT(ary, ptr, {
+        MEMMOVE(ptr+pos, ptr+pos+1, VALUE, len-pos-1);
     });
     ARY_INCREASE_LEN(ary, -1);
-
+    ary_verify(ary);
     return del;
 }
 
 /*
  *  call-seq:
- *     ary.delete_at(index)  -> obj or nil
+ *    array.delete_at(index) -> deleted_object or nil
+ *
+ *  Deletes an element from +self+, per the given \Integer +index+.
+ *
+ *  When +index+ is non-negative, deletes the element at offset +index+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.delete_at(1) # => "bar"
+ *    a # => [:foo, 2]
  *
- *  Deletes the element at the specified +index+, returning that element, or
- *  +nil+ if the +index+ is out of range.
+ *  If index is too large, returns +nil+.
  *
- *  See also Array#slice!
+ *  When +index+ is negative, counts backward from the end of the array:
  *
- *     a = ["ant", "bat", "cat", "dog"]
- *     a.delete_at(2)    #=> "cat"
- *     a                 #=> ["ant", "bat", "dog"]
- *     a.delete_at(99)   #=> nil
+ *    a = [:foo, 'bar', 2]
+ *    a.delete_at(-2) # => "bar"
+ *    a # => [:foo, 2]
+ *
+ *  If +index+ is too small (far from zero), returns nil.
  */
 
 static VALUE
@@ -3071,73 +4278,133 @@ rb_ary_delete_at_m(VALUE ary, VALUE pos)
     return rb_ary_delete_at(ary, NUM2LONG(pos));
 }
 
+static VALUE
+ary_slice_bang_by_rb_ary_splice(VALUE ary, long pos, long len)
+{
+    const long orig_len = RARRAY_LEN(ary);
+
+    if (len < 0) {
+        return Qnil;
+    }
+    else if (pos < -orig_len) {
+        return Qnil;
+    }
+    else if (pos < 0) {
+        pos += orig_len;
+    }
+    else if (orig_len < pos) {
+        return Qnil;
+    }
+    if (orig_len < pos + len) {
+        len = orig_len - pos;
+    }
+    if (len == 0) {
+        return rb_ary_new2(0);
+    }
+    else {
+        VALUE arg2 = rb_ary_new4(len, RARRAY_CONST_PTR_TRANSIENT(ary)+pos);
+        rb_ary_splice(ary, pos, len, 0, 0);
+        return arg2;
+    }
+}
+
 /*
  *  call-seq:
- *     ary.slice!(index)         -> obj or nil
- *     ary.slice!(start, length) -> new_ary or nil
- *     ary.slice!(range)         -> new_ary or nil
- *
- *  Deletes the element(s) given by an +index+ (optionally up to +length+
- *  elements) or by a +range+.
- *
- *  Returns the deleted object (or objects), or +nil+ if the +index+ is out of
- *  range.
- *
- *     a = [ "a", "b", "c" ]
- *     a.slice!(1)     #=> "b"
- *     a               #=> ["a", "c"]
- *     a.slice!(-1)    #=> "c"
- *     a               #=> ["a"]
- *     a.slice!(100)   #=> nil
- *     a               #=> ["a"]
+ *    array.slice!(n) -> object or nil
+ *    array.slice!(start, length) -> new_array or nil
+ *    array.slice!(range) -> new_array or nil
+ *
+ *  Removes and returns elements from +self+.
+ *
+ *  When the only argument is an \Integer +n+,
+ *  removes and returns the _nth_ element in +self+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.slice!(1) # => "bar"
+ *    a # => [:foo, 2]
+ *
+ *  If +n+ is negative, counts backwards from the end of +self+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.slice!(-1) # => 2
+ *    a # => [:foo, "bar"]
+ *
+ *  If +n+ is out of range, returns +nil+.
+ *
+ *  When the only arguments are Integers +start+ and +length+,
+ *  removes +length+ elements from +self+ beginning at offset  +start+;
+ *  returns the deleted objects in a new \Array:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.slice!(0, 2) # => [:foo, "bar"]
+ *    a # => [2]
+ *
+ *  If <tt>start + length</tt> exceeds the array size,
+ *  removes and returns all elements from offset +start+ to the end:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.slice!(1, 50) # => ["bar", 2]
+ *    a # => [:foo]
+ *
+ *  If <tt>start == a.size</tt> and +length+ is non-negative,
+ *  returns a new empty \Array.
+ *
+ *  If +length+ is negative, returns +nil+.
+ *
+ *  When the only argument is a \Range object +range+,
+ *  treats <tt>range.min</tt> as +start+ above and <tt>range.size</tt> as +length+ above:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.slice!(1..2) # => ["bar", 2]
+ *    a # => [:foo]
+ *
+ *  If <tt>range.start == a.size</tt>, returns a new empty \Array.
+ *
+ *  If <tt>range.start</tt> is larger than the array size, returns +nil+.
+ *
+ *  If <tt>range.end</tt> is negative, counts backwards from the end of the array:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.slice!(0..-2) # => [:foo, "bar"]
+ *    a # => [2]
+ *
+ *  If <tt>range.start</tt> is negative,
+ *  calculates the start index backwards from the end of the array:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.slice!(-2..2) # => ["bar", 2]
+ *    a # => [:foo]
+ *
  */
 
 static VALUE
 rb_ary_slice_bang(int argc, VALUE *argv, VALUE ary)
 {
-    VALUE arg1, arg2;
-    long pos, len, orig_len;
+    VALUE arg1;
+    long pos, len;
 
     rb_ary_modify_check(ary);
+    rb_check_arity(argc, 1, 2);
+    arg1 = argv[0];
+
     if (argc == 2) {
-	pos = NUM2LONG(argv[0]);
-	len = NUM2LONG(argv[1]);
-      delete_pos_len:
-	if (len < 0) return Qnil;
-	orig_len = RARRAY_LEN(ary);
-	if (pos < 0) {
-	    pos += orig_len;
-	    if (pos < 0) return Qnil;
-	}
-	else if (orig_len < pos) return Qnil;
-	if (orig_len < pos + len) {
-	    len = orig_len - pos;
-	}
-	if (len == 0) return rb_ary_new2(0);
-	arg2 = rb_ary_new4(len, RARRAY_CONST_PTR(ary)+pos);
-	RBASIC_SET_CLASS(arg2, rb_obj_class(ary));
-	rb_ary_splice(ary, pos, len, Qundef);
-	return arg2;
-    }
-
-    if (argc != 1) {
-	/* error report */
-	rb_scan_args(argc, argv, "11", NULL, NULL);
+        pos = NUM2LONG(argv[0]);
+        len = NUM2LONG(argv[1]);
+        return ary_slice_bang_by_rb_ary_splice(ary, pos, len);
     }
-    arg1 = argv[0];
 
     if (!FIXNUM_P(arg1)) {
-	switch (rb_range_beg_len(arg1, &pos, &len, RARRAY_LEN(ary), 0)) {
-	  case Qtrue:
-	    /* valid range */
-	    goto delete_pos_len;
-	  case Qnil:
-	    /* invalid range */
-	    return Qnil;
-	  default:
-	    /* not a range */
-	    break;
-	}
+        switch (rb_range_beg_len(arg1, &pos, &len, RARRAY_LEN(ary), 0)) {
+          case Qtrue:
+            /* valid range */
+            return ary_slice_bang_by_rb_ary_splice(ary, pos, len);
+          case Qnil:
+            /* invalid range */
+            return Qnil;
+          default:
+            /* not a range */
+            break;
+        }
     }
 
     return rb_ary_delete_at(ary, NUM2LONG(arg1));
@@ -3149,10 +4416,11 @@ ary_reject(VALUE orig, VALUE result)
     long i;
 
     for (i = 0; i < RARRAY_LEN(orig); i++) {
-	VALUE v = RARRAY_AREF(orig, i);
-	if (!RTEST(rb_yield(v))) {
-	    rb_ary_push(result, v);
-	}
+        VALUE v = RARRAY_AREF(orig, i);
+
+        if (!RTEST(rb_yield(v))) {
+            rb_ary_push(result, v);
+        }
     }
     return result;
 }
@@ -3165,12 +4433,12 @@ reject_bang_i(VALUE a)
     long i1, i2;
 
     for (i1 = i2 = 0; i1 < RARRAY_LEN(ary); arg->len[0] = ++i1) {
-	VALUE v = RARRAY_AREF(ary, i1);
-	if (RTEST(rb_yield(v))) continue;
-	if (i1 != i2) {
-	    rb_ary_store(ary, i2, v);
-	}
-	arg->len[1] = ++i2;
+        VALUE v = RARRAY_AREF(ary, i1);
+        if (RTEST(rb_yield(v))) continue;
+        if (i1 != i2) {
+            rb_ary_store(ary, i2, v);
+        }
+        arg->len[1] = ++i2;
     }
     return (i1 == i2) ? Qnil : ary;
 }
@@ -3179,7 +4447,6 @@ static VALUE
 ary_reject_bang(VALUE ary)
 {
     struct select_bang_arg args;
-
     rb_ary_modify_check(ary);
     args.ary = ary;
     args.len[0] = args.len[1] = 0;
@@ -3188,37 +4455,50 @@ ary_reject_bang(VALUE ary)
 
 /*
  *  call-seq:
- *     ary.reject! { |item| block }  -> ary or nil
- *     ary.reject!                   -> Enumerator
+ *    array.reject! {|element| ... } -> self or nil
+ *    array.reject! -> new_enumerator
  *
- *  Deletes every element of +self+ for which the block evaluates to +true+,
- *  if no changes were made returns +nil+.
+ *  Removes each element for which the block returns a truthy value.
  *
- *  The array may not be changed instantly every time the block is called.
+ *  Returns +self+ if any elements removed:
  *
- *  See also Enumerable#reject and Array#delete_if.
+ *    a = [:foo, 'bar', 2, 'bat']
+ *    a.reject! {|element| element.to_s.start_with?('b') } # => [:foo, 2]
+ *
+ *  Returns +nil+ if no elements removed.
+ *
+ *  Returns a new \Enumerator if no block given:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.reject! # => #<Enumerator: [:foo, "bar", 2]:reject!>
  *
- *  If no block is given, an Enumerator is returned instead.
  */
 
 static VALUE
 rb_ary_reject_bang(VALUE ary)
 {
     RETURN_SIZED_ENUMERATOR(ary, 0, 0, ary_enum_length);
+    rb_ary_modify(ary);
     return ary_reject_bang(ary);
 }
 
 /*
  *  call-seq:
- *     ary.reject  {|item| block }  -> new_ary
- *     ary.reject                   -> Enumerator
+ *    array.reject {|element| ... } -> new_array
+ *    array.reject -> new_enumerator
  *
- *  Returns a new array containing the items in +self+ for which the given
- *  block is not +true+. The ordering of non-rejected elements is maintained.
+ *  Returns a new \Array whose elements are all those from +self+
+ *  for which the block returns +false+ or +nil+:
  *
- *  See also Array#delete_if
+ *    a = [:foo, 'bar', 2, 'bat']
+ *    a1 = a.reject {|element| element.to_s.start_with?('b') }
+ *    a1 # => [:foo, 2]
+ *
+ *  Returns a new \Enumerator if no block given:
+ *
+ *     a = [:foo, 'bar', 2]
+ *     a.reject # => #<Enumerator: [:foo, "bar", 2]:reject>
  *
- *  If no block is given, an Enumerator is returned instead.
  */
 
 static VALUE
@@ -3234,25 +4514,26 @@ rb_ary_reject(VALUE ary)
 
 /*
  *  call-seq:
- *     ary.delete_if { |item| block }  -> ary
- *     ary.delete_if                   -> Enumerator
+ *    array.delete_if {|element| ... } -> self
+ *    array.delete_if -> Enumerator
  *
- *  Deletes every element of +self+ for which block evaluates to +true+.
+ *  Removes each element in +self+ for which the block returns a truthy value;
+ *  returns +self+:
  *
- *  The array is changed instantly every time the block is called, not after
- *  the iteration is over.
+ *    a = [:foo, 'bar', 2, 'bat']
+ *    a.delete_if {|element| element.to_s.start_with?('b') } # => [:foo, 2]
  *
- *  See also Array#reject!
+ *  Returns a new \Enumerator if no block given:
  *
- *  If no block is given, an Enumerator is returned instead.
+ *    a = [:foo, 'bar', 2]
+ *    a.delete_if # => #<Enumerator: [:foo, "bar", 2]:delete_if>
  *
- *     scores = [ 97, 42, 75 ]
- *     scores.delete_if {|score| score < 80 }   #=> [97]
- */
+3 */
 
 static VALUE
 rb_ary_delete_if(VALUE ary)
 {
+    ary_verify(ary);
     RETURN_SIZED_ENUMERATOR(ary, 0, 0, ary_enum_length);
     ary_reject_bang(ary);
     return ary;
@@ -3262,9 +4543,9 @@ static VALUE
 take_i(RB_BLOCK_CALL_FUNC_ARGLIST(val, cbarg))
 {
     VALUE *args = (VALUE *)cbarg;
-    if (args[1]-- == 0) rb_iter_break();
     if (argc > 1) val = rb_ary_new4(argc, argv);
     rb_ary_push(args[0], val);
+    if (--args[1] == 0) rb_iter_break();
     return Qnil;
 }
 
@@ -3274,38 +4555,71 @@ take_items(VALUE obj, long n)
     VALUE result = rb_check_array_type(obj);
     VALUE args[2];
 
+    if (n == 0) return result;
     if (!NIL_P(result)) return rb_ary_subseq(result, 0, n);
     result = rb_ary_new2(n);
     args[0] = result; args[1] = (VALUE)n;
-    if (rb_check_block_call(obj, idEach, 0, 0, take_i, (VALUE)args) == Qundef)
-	rb_raise(rb_eTypeError, "wrong argument type %"PRIsVALUE" (must respond to :each)",
-		 rb_obj_class(obj));
+    if (UNDEF_P(rb_check_block_call(obj, idEach, 0, 0, take_i, (VALUE)args)))
+        rb_raise(rb_eTypeError, "wrong argument type %"PRIsVALUE" (must respond to :each)",
+                 rb_obj_class(obj));
     return result;
 }
 
 
 /*
  *  call-seq:
- *     ary.zip(arg, ...)                  -> new_ary
- *     ary.zip(arg, ...) { |arr| block }  -> nil
+ *    array.zip(*other_arrays) -> new_array
+ *    array.zip(*other_arrays) {|other_array| ... } -> nil
+ *
+ *  When no block given, returns a new \Array +new_array+ of size <tt>self.size</tt>
+ *  whose elements are Arrays.
+ *
+ *  Each nested array <tt>new_array[n]</tt> is of size <tt>other_arrays.size+1</tt>,
+ *  and contains:
+ *
+ *  - The _nth_ element of +self+.
+ *  - The _nth_ element of each of the +other_arrays+.
+ *
+ *  If all +other_arrays+ and +self+ are the same size:
+ *
+ *    a = [:a0, :a1, :a2, :a3]
+ *    b = [:b0, :b1, :b2, :b3]
+ *    c = [:c0, :c1, :c2, :c3]
+ *    d = a.zip(b, c)
+ *    d # => [[:a0, :b0, :c0], [:a1, :b1, :c1], [:a2, :b2, :c2], [:a3, :b3, :c3]]
+ *
+ *  If any array in +other_arrays+ is smaller than +self+,
+ *  fills to <tt>self.size</tt> with +nil+:
  *
- *  Converts any arguments to arrays, then merges elements of +self+ with
- *  corresponding elements from each argument.
+ *    a = [:a0, :a1, :a2, :a3]
+ *    b = [:b0, :b1, :b2]
+ *    c = [:c0, :c1]
+ *    d = a.zip(b, c)
+ *    d # => [[:a0, :b0, :c0], [:a1, :b1, :c1], [:a2, :b2, nil], [:a3, nil, nil]]
  *
- *  This generates a sequence of <code>ary.size</code> _n_-element arrays,
- *  where _n_ is one more than the count of arguments.
+ *  If any array in +other_arrays+ is larger than +self+,
+ *  its trailing elements are ignored:
  *
- *  If the size of any argument is less than the size of the initial array,
- *  +nil+ values are supplied.
+ *    a = [:a0, :a1, :a2, :a3]
+ *    b = [:b0, :b1, :b2, :b3, :b4]
+ *    c = [:c0, :c1, :c2, :c3, :c4, :c5]
+ *    d = a.zip(b, c)
+ *    d # => [[:a0, :b0, :c0], [:a1, :b1, :c1], [:a2, :b2, :c2], [:a3, :b3, :c3]]
  *
- *  If a block is given, it is invoked for each output +array+, otherwise an
- *  array of arrays is returned.
+ *  When a block is given, calls the block with each of the sub-arrays (formed as above); returns +nil+:
+ *
+ *    a = [:a0, :a1, :a2, :a3]
+ *    b = [:b0, :b1, :b2, :b3]
+ *    c = [:c0, :c1, :c2, :c3]
+ *    a.zip(b, c) {|sub_array| p sub_array} # => nil
+ *
+ *  Output:
+ *
+ *    [:a0, :b0, :c0]
+ *    [:a1, :b1, :c1]
+ *    [:a2, :b2, :c2]
+ *    [:a3, :b3, :c3]
  *
- *     a = [ 4, 5, 6 ]
- *     b = [ 7, 8, 9 ]
- *     [1, 2, 3].zip(a, b)   #=> [[1, 4, 7], [2, 5, 8], [3, 6, 9]]
- *     [1, 2].zip(a, b)      #=> [[1, 4, 7], [2, 5, 8]]
- *     a.zip([1, 2], [8])    #=> [[4, 1, 8], [5, 2, nil], [6, nil, nil]]
  */
 
 static VALUE
@@ -3316,51 +4630,51 @@ rb_ary_zip(int argc, VALUE *argv, VALUE ary)
     VALUE result = Qnil;
 
     for (i=0; i<argc; i++) {
-	argv[i] = take_items(argv[i], len);
+        argv[i] = take_items(argv[i], len);
     }
 
     if (rb_block_given_p()) {
-	int arity = rb_block_arity();
-
-	if (arity > 1) {
-	    VALUE work, *tmp;
-
-	    tmp = ALLOCV_N(VALUE, work, argc+1);
-
-	    for (i=0; i<RARRAY_LEN(ary); i++) {
-		tmp[0] = RARRAY_AREF(ary, i);
-		for (j=0; j<argc; j++) {
-		    tmp[j+1] = rb_ary_elt(argv[j], i);
-		}
-		rb_yield_values2(argc+1, tmp);
-	    }
-
-	    if (work) ALLOCV_END(work);
-	}
-	else {
-	    for (i=0; i<RARRAY_LEN(ary); i++) {
-		VALUE tmp = rb_ary_new2(argc+1);
-
-		rb_ary_push(tmp, RARRAY_AREF(ary, i));
-		for (j=0; j<argc; j++) {
-		    rb_ary_push(tmp, rb_ary_elt(argv[j], i));
-		}
-		rb_yield(tmp);
-	    }
-	}
+        int arity = rb_block_arity();
+
+        if (arity > 1) {
+            VALUE work, *tmp;
+
+            tmp = ALLOCV_N(VALUE, work, argc+1);
+
+            for (i=0; i<RARRAY_LEN(ary); i++) {
+                tmp[0] = RARRAY_AREF(ary, i);
+                for (j=0; j<argc; j++) {
+                    tmp[j+1] = rb_ary_elt(argv[j], i);
+                }
+                rb_yield_values2(argc+1, tmp);
+            }
+
+            if (work) ALLOCV_END(work);
+        }
+        else {
+            for (i=0; i<RARRAY_LEN(ary); i++) {
+                VALUE tmp = rb_ary_new2(argc+1);
+
+                rb_ary_push(tmp, RARRAY_AREF(ary, i));
+                for (j=0; j<argc; j++) {
+                    rb_ary_push(tmp, rb_ary_elt(argv[j], i));
+                }
+                rb_yield(tmp);
+            }
+        }
     }
     else {
-	result = rb_ary_new_capa(len);
+        result = rb_ary_new_capa(len);
 
-	for (i=0; i<len; i++) {
-	    VALUE tmp = rb_ary_new_capa(argc+1);
+        for (i=0; i<len; i++) {
+            VALUE tmp = rb_ary_new_capa(argc+1);
 
-	    rb_ary_push(tmp, RARRAY_AREF(ary, i));
-	    for (j=0; j<argc; j++) {
-		rb_ary_push(tmp, rb_ary_elt(argv[j], i));
-	    }
-	    rb_ary_push(result, tmp);
-	}
+            rb_ary_push(tmp, RARRAY_AREF(ary, i));
+            for (j=0; j<argc; j++) {
+                rb_ary_push(tmp, rb_ary_elt(argv[j], i));
+            }
+            rb_ary_push(result, tmp);
+        }
     }
 
     return result;
@@ -3368,15 +4682,14 @@ rb_ary_zip(int argc, VALUE *argv, VALUE ary)
 
 /*
  *  call-seq:
- *     ary.transpose -> new_ary
+ *    array.transpose -> new_array
  *
- *  Assumes that +self+ is an array of arrays and transposes the rows and
- *  columns.
+ *  Transposes the rows and columns in an \Array of Arrays;
+ *  the nested Arrays must all be the same size:
  *
- *     a = [[1,2], [3,4], [5,6]]
- *     a.transpose   #=> [[1, 3, 5], [2, 4, 6]]
+ *    a = [[:a0, :a1], [:b0, :b1], [:c0, :c1]]
+ *    a.transpose # => [[:a0, :b0, :c0], [:a1, :b1, :c1]]
  *
- *  If the length of the subarrays don't match, an IndexError is raised.
  */
 
 static VALUE
@@ -3388,36 +4701,34 @@ rb_ary_transpose(VALUE ary)
     alen = RARRAY_LEN(ary);
     if (alen == 0) return rb_ary_dup(ary);
     for (i=0; i<alen; i++) {
-	tmp = to_ary(rb_ary_elt(ary, i));
-	if (elen < 0) {		/* first element */
-	    elen = RARRAY_LEN(tmp);
-	    result = rb_ary_new2(elen);
-	    for (j=0; j<elen; j++) {
-		rb_ary_store(result, j, rb_ary_new2(alen));
-	    }
-	}
-	else if (elen != RARRAY_LEN(tmp)) {
-	    rb_raise(rb_eIndexError, "element size differs (%ld should be %ld)",
-		     RARRAY_LEN(tmp), elen);
-	}
-	for (j=0; j<elen; j++) {
-	    rb_ary_store(rb_ary_elt(result, j), i, rb_ary_elt(tmp, j));
-	}
+        tmp = to_ary(rb_ary_elt(ary, i));
+        if (elen < 0) {		/* first element */
+            elen = RARRAY_LEN(tmp);
+            result = rb_ary_new2(elen);
+            for (j=0; j<elen; j++) {
+                rb_ary_store(result, j, rb_ary_new2(alen));
+            }
+        }
+        else if (elen != RARRAY_LEN(tmp)) {
+            rb_raise(rb_eIndexError, "element size differs (%ld should be %ld)",
+                     RARRAY_LEN(tmp), elen);
+        }
+        for (j=0; j<elen; j++) {
+            rb_ary_store(rb_ary_elt(result, j), i, rb_ary_elt(tmp, j));
+        }
     }
     return result;
 }
 
 /*
  *  call-seq:
- *     ary.replace(other_ary)  -> ary
- *     ary.initialize_copy(other_ary)	-> ary
+ *    array.replace(other_array) -> self
  *
- *  Replaces the contents of +self+ with the contents of +other_ary+,
- *  truncating or expanding if necessary.
+ *  Replaces the content of +self+ with the content of +other_array+; returns +self+:
+ *
+ *    a = [:foo, 'bar', 2]
+ *    a.replace(['foo', :bar, 3]) # => ["foo", :bar, 3]
  *
- *     a = [ "a", "b", "c", "d", "e" ]
- *     a.replace([ "x", "y", "z" ])   #=> ["x", "y", "z"]
- *     a                              #=> ["x", "y", "z"]
  */
 
 VALUE
@@ -3427,94 +4738,270 @@ rb_ary_replace(VALUE copy, VALUE orig)
     orig = to_ary(orig);
     if (copy == orig) return copy;
 
-    if (RARRAY_LEN(orig) <= RARRAY_EMBED_LEN_MAX) {
-        VALUE shared = 0;
+    rb_ary_reset(copy);
 
-        if (ARY_OWNS_HEAP_P(copy)) {
-	    RARRAY_PTR_USE(copy, ptr, ruby_sized_xfree(ptr, ARY_HEAP_SIZE(copy)));
-	}
-        else if (ARY_SHARED_P(copy)) {
-            shared = ARY_SHARED(copy);
-            FL_UNSET_SHARED(copy);
-        }
-        FL_SET_EMBED(copy);
-	ary_memcpy(copy, 0, RARRAY_LEN(orig), RARRAY_CONST_PTR(orig));
-        if (shared) {
-            rb_ary_decrement_share(shared);
-        }
-        ARY_SET_LEN(copy, RARRAY_LEN(orig));
+    /* orig has enough space to embed the contents of orig. */
+    if (RARRAY_LEN(orig) <= ary_embed_capa(copy)) {
+        assert(ARY_EMBED_P(copy));
+        ary_memcpy(copy, 0, RARRAY_LEN(orig), RARRAY_CONST_PTR_TRANSIENT(orig));
+        ARY_SET_EMBED_LEN(copy, RARRAY_LEN(orig));
+    }
+#if USE_RVARGC
+    /* orig is embedded but copy does not have enough space to embed the
+     * contents of orig. */
+    else if (ARY_EMBED_P(orig)) {
+        long len = ARY_EMBED_LEN(orig);
+        VALUE *ptr = ary_heap_alloc(copy, len);
+
+        FL_UNSET_EMBED(copy);
+        ARY_SET_PTR(copy, ptr);
+        ARY_SET_LEN(copy, len);
+        ARY_SET_CAPA(copy, len);
+
+        // No allocation and exception expected that could leave `copy` in a
+        // bad state from the edits above.
+        ary_memcpy(copy, 0, len, RARRAY_CONST_PTR_TRANSIENT(orig));
     }
+#endif
+    /* Otherwise, orig is on heap and copy does not have enough space to embed
+     * the contents of orig. */
     else {
-        VALUE shared = ary_make_shared(orig);
-        if (ARY_OWNS_HEAP_P(copy)) {
-	    RARRAY_PTR_USE(copy, ptr, ruby_sized_xfree(ptr, ARY_HEAP_SIZE(copy)));
-        }
-        else {
-            rb_ary_unshare_safe(copy);
-        }
+        VALUE shared_root = ary_make_shared(orig);
         FL_UNSET_EMBED(copy);
-        ARY_SET_PTR(copy, RARRAY_CONST_PTR(orig));
-        ARY_SET_LEN(copy, RARRAY_LEN(orig));
-        rb_ary_set_shared(copy, shared);
+        ARY_SET_PTR(copy, ARY_HEAP_PTR(orig));
+        ARY_SET_LEN(copy, ARY_HEAP_LEN(orig));
+        rb_ary_set_shared(copy, shared_root);
     }
+    ary_verify(copy);
     return copy;
 }
 
 /*
  *  call-seq:
- *     ary.clear    -> ary
+ *     array.clear -> self
+ *
+ *  Removes all elements from +self+:
  *
- *  Removes all elements from +self+.
+ *    a = [:foo, 'bar', 2]
+ *    a.clear # => []
  *
- *     a = [ "a", "b", "c", "d", "e" ]
- *     a.clear    #=> [ ]
  */
 
 VALUE
 rb_ary_clear(VALUE ary)
 {
     rb_ary_modify_check(ary);
-    ARY_SET_LEN(ary, 0);
     if (ARY_SHARED_P(ary)) {
-	if (!ARY_EMBED_P(ary)) {
-	    rb_ary_unshare(ary);
-	    FL_SET_EMBED(ary);
-	}
+        if (!ARY_EMBED_P(ary)) {
+            rb_ary_unshare(ary);
+            FL_SET_EMBED(ary);
+            ARY_SET_EMBED_LEN(ary, 0);
+        }
     }
-    else if (ARY_DEFAULT_SIZE * 2 < ARY_CAPA(ary)) {
-	ary_resize_capa(ary, ARY_DEFAULT_SIZE * 2);
+    else {
+        ARY_SET_LEN(ary, 0);
+        if (ARY_DEFAULT_SIZE * 2 < ARY_CAPA(ary)) {
+            ary_resize_capa(ary, ARY_DEFAULT_SIZE * 2);
+        }
     }
+    ary_verify(ary);
     return ary;
 }
 
 /*
  *  call-seq:
- *     ary.fill(obj)                                 -> ary
- *     ary.fill(obj, start [, length])               -> ary
- *     ary.fill(obj, range )                         -> ary
- *     ary.fill { |index| block }                    -> ary
- *     ary.fill(start [, length] ) { |index| block } -> ary
- *     ary.fill(range) { |index| block }             -> ary
+ *    array.fill(obj) -> self
+ *    array.fill(obj, start) -> self
+ *    array.fill(obj, start, length) -> self
+ *    array.fill(obj, range) -> self
+ *    array.fill {|index| ... } -> self
+ *    array.fill(start) {|index| ... } -> self
+ *    array.fill(start, length) {|index| ... } -> self
+ *    array.fill(range) {|index| ... } -> self
+ *
+ *  Replaces specified elements in +self+ with specified objects; returns +self+.
+ *
+ *  With argument +obj+ and no block given, replaces all elements with that one object:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a # => ["a", "b", "c", "d"]
+ *    a.fill(:X) # => [:X, :X, :X, :X]
+ *
+ *  With arguments +obj+ and \Integer +start+, and no block given,
+ *  replaces elements based on the given start.
+ *
+ *  If +start+ is in range (<tt>0 <= start < array.size</tt>),
+ *  replaces all elements from offset +start+ through the end:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(:X, 2) # => ["a", "b", :X, :X]
+ *
+ *  If +start+ is too large (<tt>start >= array.size</tt>), does nothing:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(:X, 4) # => ["a", "b", "c", "d"]
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(:X, 5) # => ["a", "b", "c", "d"]
+ *
+ *  If +start+ is negative, counts from the end (starting index is <tt>start + array.size</tt>):
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(:X, -2) # => ["a", "b", :X, :X]
+ *
+ *  If +start+ is too small (less than and far from zero), replaces all elements:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(:X, -6) # => [:X, :X, :X, :X]
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(:X, -50) # => [:X, :X, :X, :X]
+ *
+ *  With arguments +obj+, \Integer +start+, and \Integer +length+, and no block given,
+ *  replaces elements based on the given +start+ and +length+.
+ *
+ *  If +start+ is in range, replaces +length+ elements beginning at offset +start+:
  *
- *  The first three forms set the selected elements of +self+ (which
- *  may be the entire array) to +obj+.
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(:X, 1, 1) # => ["a", :X, "c", "d"]
  *
- *  A +start+ of +nil+ is equivalent to zero.
+ *  If +start+ is negative, counts from the end:
  *
- *  A +length+ of +nil+ is equivalent to the length of the array.
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(:X, -2, 1) # => ["a", "b", :X, "d"]
  *
- *  The last three forms fill the array with the value of the given block,
- *  which is passed the absolute index of each element to be filled.
+ *  If +start+ is large (<tt>start >= array.size</tt>), extends +self+ with +nil+:
  *
- *  Negative values of +start+ count from the end of the array, where +-1+ is
- *  the last element.
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(:X, 5, 0) # => ["a", "b", "c", "d", nil]
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(:X, 5, 2) # => ["a", "b", "c", "d", nil, :X, :X]
+ *
+ *  If +length+ is zero or negative, replaces no elements:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(:X, 1, 0) # => ["a", "b", "c", "d"]
+ *    a.fill(:X, 1, -1) # => ["a", "b", "c", "d"]
+ *
+ *  With arguments +obj+ and \Range +range+, and no block given,
+ *  replaces elements based on the given range.
+ *
+ *  If the range is positive and ascending (<tt>0 < range.begin <= range.end</tt>),
+ *  replaces elements from <tt>range.begin</tt> to <tt>range.end</tt>:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(:X, (1..1)) # => ["a", :X, "c", "d"]
+ *
+ *  If <tt>range.first</tt> is negative, replaces no elements:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(:X, (-1..1)) # => ["a", "b", "c", "d"]
+ *
+ *  If <tt>range.last</tt> is negative, counts from the end:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(:X, (0..-2)) # => [:X, :X, :X, "d"]
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(:X, (1..-2)) # => ["a", :X, :X, "d"]
+ *
+ *  If <tt>range.last</tt> and <tt>range.last</tt> are both negative,
+ *  both count from the end of the array:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(:X, (-1..-1)) # => ["a", "b", "c", :X]
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(:X, (-2..-2)) # => ["a", "b", :X, "d"]
+ *
+ *  With no arguments and a block given, calls the block with each index;
+ *  replaces the corresponding element with the block's return value:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill { |index| "new_#{index}" } # => ["new_0", "new_1", "new_2", "new_3"]
+ *
+ *  With argument +start+ and a block given, calls the block with each index
+ *  from offset +start+ to the end; replaces the corresponding element
+ *  with the block's return value.
+ *
+ *  If start is in range (<tt>0 <= start < array.size</tt>),
+ *  replaces from offset +start+ to the end:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(1) { |index| "new_#{index}" } # => ["a", "new_1", "new_2", "new_3"]
+ *
+ *  If +start+ is too large(<tt>start >= array.size</tt>), does nothing:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(4) { |index| fail 'Cannot happen' } # => ["a", "b", "c", "d"]
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(4) { |index| fail 'Cannot happen' } # => ["a", "b", "c", "d"]
+ *
+ *  If +start+ is negative, counts from the end:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(-2) { |index| "new_#{index}" } # => ["a", "b", "new_2", "new_3"]
+ *
+ *  If start is too small (<tt>start <= -array.size</tt>, replaces all elements:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(-6) { |index| "new_#{index}" } # => ["new_0", "new_1", "new_2", "new_3"]
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(-50) { |index| "new_#{index}" } # => ["new_0", "new_1", "new_2", "new_3"]
+ *
+ *  With arguments +start+ and +length+, and a block given,
+ *  calls the block for each index specified by start length;
+ *  replaces the corresponding element with the block's return value.
+ *
+ *  If +start+ is in range, replaces +length+ elements beginning at offset +start+:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(1, 1) { |index| "new_#{index}" } # => ["a", "new_1", "c", "d"]
+ *
+ *  If start is negative, counts from the end:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(-2, 1) { |index| "new_#{index}" } # => ["a", "b", "new_2", "d"]
+ *
+ *  If +start+ is large (<tt>start >= array.size</tt>), extends +self+ with +nil+:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(5, 0) { |index| "new_#{index}" } # => ["a", "b", "c", "d", nil]
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(5, 2) { |index| "new_#{index}" } # => ["a", "b", "c", "d", nil, "new_5", "new_6"]
+ *
+ *  If +length+ is zero or less, replaces no elements:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(1, 0) { |index| "new_#{index}" } # => ["a", "b", "c", "d"]
+ *    a.fill(1, -1) { |index| "new_#{index}" } # => ["a", "b", "c", "d"]
+ *
+ *  With arguments +obj+ and +range+, and a block given,
+ *  calls the block with each index in the given range;
+ *  replaces the corresponding element with the block's return value.
+ *
+ *  If the range is positive and ascending (<tt>range 0 < range.begin <= range.end</tt>,
+ *  replaces elements from <tt>range.begin</tt> to <tt>range.end</tt>:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(1..1) { |index| "new_#{index}" } # => ["a", "new_1", "c", "d"]
+ *
+ *  If +range.first+ is negative, does nothing:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(-1..1) { |index| fail 'Cannot happen' } # => ["a", "b", "c", "d"]
+ *
+ *  If <tt>range.last</tt> is negative, counts from the end:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(0..-2) { |index| "new_#{index}" } # => ["new_0", "new_1", "new_2", "d"]
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(1..-2) { |index| "new_#{index}" } # => ["a", "new_1", "new_2", "d"]
+ *
+ *  If <tt>range.first</tt> and <tt>range.last</tt> are both negative,
+ *  both count from the end:
+ *
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(-1..-1) { |index| "new_#{index}" } # => ["a", "b", "c", "new_3"]
+ *    a = ['a', 'b', 'c', 'd']
+ *    a.fill(-2..-2) { |index| "new_#{index}" } # => ["a", "b", "new_2", "d"]
  *
- *     a = [ "a", "b", "c", "d" ]
- *     a.fill("x")              #=> ["x", "x", "x", "x"]
- *     a.fill("z", 2, 2)        #=> ["x", "x", "z", "z"]
- *     a.fill("y", 0..1)        #=> ["y", "y", "z", "z"]
- *     a.fill { |i| i*i }       #=> [0, 1, 4, 9]
- *     a.fill(-2) { |i| i*i*i } #=> [0, 1, 8, 27]
  */
 
 static VALUE
@@ -3524,84 +5011,74 @@ rb_ary_fill(int argc, VALUE *argv, VALUE ary)
     long beg = 0, end = 0, len = 0;
 
     if (rb_block_given_p()) {
-	rb_scan_args(argc, argv, "02", &arg1, &arg2);
-	argc += 1;		/* hackish */
+        rb_scan_args(argc, argv, "02", &arg1, &arg2);
+        argc += 1;		/* hackish */
     }
     else {
-	rb_scan_args(argc, argv, "12", &item, &arg1, &arg2);
+        rb_scan_args(argc, argv, "12", &item, &arg1, &arg2);
     }
     switch (argc) {
       case 1:
-	beg = 0;
-	len = RARRAY_LEN(ary);
-	break;
+        beg = 0;
+        len = RARRAY_LEN(ary);
+        break;
       case 2:
-	if (rb_range_beg_len(arg1, &beg, &len, RARRAY_LEN(ary), 1)) {
-	    break;
-	}
-	/* fall through */
+        if (rb_range_beg_len(arg1, &beg, &len, RARRAY_LEN(ary), 1)) {
+            break;
+        }
+        /* fall through */
       case 3:
-	beg = NIL_P(arg1) ? 0 : NUM2LONG(arg1);
-	if (beg < 0) {
-	    beg = RARRAY_LEN(ary) + beg;
-	    if (beg < 0) beg = 0;
-	}
-	len = NIL_P(arg2) ? RARRAY_LEN(ary) - beg : NUM2LONG(arg2);
-	break;
+        beg = NIL_P(arg1) ? 0 : NUM2LONG(arg1);
+        if (beg < 0) {
+            beg = RARRAY_LEN(ary) + beg;
+            if (beg < 0) beg = 0;
+        }
+        len = NIL_P(arg2) ? RARRAY_LEN(ary) - beg : NUM2LONG(arg2);
+        break;
     }
     rb_ary_modify(ary);
     if (len < 0) {
         return ary;
     }
     if (beg >= ARY_MAX_SIZE || len > ARY_MAX_SIZE - beg) {
-	rb_raise(rb_eArgError, "argument too big");
+        rb_raise(rb_eArgError, "argument too big");
     }
     end = beg + len;
     if (RARRAY_LEN(ary) < end) {
-	if (end >= ARY_CAPA(ary)) {
-	    ary_resize_capa(ary, end);
-	}
-	ary_mem_clear(ary, RARRAY_LEN(ary), end - RARRAY_LEN(ary));
-	ARY_SET_LEN(ary, end);
+        if (end >= ARY_CAPA(ary)) {
+            ary_resize_capa(ary, end);
+        }
+        ary_mem_clear(ary, RARRAY_LEN(ary), end - RARRAY_LEN(ary));
+        ARY_SET_LEN(ary, end);
     }
 
-    if (item == Qundef) {
-	VALUE v;
-	long i;
+    if (UNDEF_P(item)) {
+        VALUE v;
+        long i;
 
-	for (i=beg; i<end; i++) {
-	    v = rb_yield(LONG2NUM(i));
-	    if (i>=RARRAY_LEN(ary)) break;
-	    ARY_SET(ary, i, v);
-	}
+        for (i=beg; i<end; i++) {
+            v = rb_yield(LONG2NUM(i));
+            if (i>=RARRAY_LEN(ary)) break;
+            ARY_SET(ary, i, v);
+        }
     }
     else {
-	ary_memfill(ary, beg, len, item);
+        ary_memfill(ary, beg, len, item);
     }
     return ary;
 }
 
 /*
  *  call-seq:
- *     ary + other_ary   -> new_ary
- *
- *  Concatenation --- Returns a new array built by concatenating the
- *  two arrays together to produce a third array.
+ *    array + other_array -> new_array
  *
- *     [ 1, 2, 3 ] + [ 4, 5 ]    #=> [ 1, 2, 3, 4, 5 ]
- *     a = [ "a", "b", "c" ]
- *     c = a + [ "d", "e", "f" ]
- *     c                         #=> [ "a", "b", "c", "d", "e", "f" ]
- *     a                         #=> [ "a", "b", "c" ]
+ *  Returns a new \Array containing all elements of +array+
+ *  followed by all elements of +other_array+:
  *
- *  Note that
- *     x += y
- *  is the same as
- *     x = x + y
- *  This means that it produces a new array. As a consequence,
- *  repeated use of <code>+=</code> on arrays can be quite inefficient.
+ *    a = [0, 1] + [2, 3]
+ *    a # => [0, 1, 2, 3]
  *
- *  See also Array#concat.
+ *  Related: #concat.
  */
 
 VALUE
@@ -3616,52 +5093,75 @@ rb_ary_plus(VALUE x, VALUE y)
     len = xlen + ylen;
     z = rb_ary_new2(len);
 
-    ary_memcpy(z, 0, xlen, RARRAY_CONST_PTR(x));
-    ary_memcpy(z, xlen, ylen, RARRAY_CONST_PTR(y));
+    ary_memcpy(z, 0, xlen, RARRAY_CONST_PTR_TRANSIENT(x));
+    ary_memcpy(z, xlen, ylen, RARRAY_CONST_PTR_TRANSIENT(y));
     ARY_SET_LEN(z, len);
     return z;
 }
 
+static VALUE
+ary_append(VALUE x, VALUE y)
+{
+    long n = RARRAY_LEN(y);
+    if (n > 0) {
+        rb_ary_splice(x, RARRAY_LEN(x), 0, RARRAY_CONST_PTR_TRANSIENT(y), n);
+    }
+    RB_GC_GUARD(y);
+    return x;
+}
+
 /*
  *  call-seq:
- *     ary.concat(other_ary)   -> ary
+ *    array.concat(*other_arrays) -> self
  *
- *  Appends the elements of +other_ary+ to +self+.
+ *  Adds to +array+ all elements from each \Array in +other_arrays+; returns +self+:
  *
- *     [ "a", "b" ].concat( ["c", "d"] ) #=> [ "a", "b", "c", "d" ]
- *     a = [ 1, 2, 3 ]
- *     a.concat( [ 4, 5 ] )
- *     a                                 #=> [ 1, 2, 3, 4, 5 ]
- *
- *  See also Array#+.
+ *    a = [0, 1]
+ *    a.concat([2, 3], [4, 5]) # => [0, 1, 2, 3, 4, 5]
  */
 
-VALUE
-rb_ary_concat(VALUE x, VALUE y)
+static VALUE
+rb_ary_concat_multi(int argc, VALUE *argv, VALUE ary)
 {
-    rb_ary_modify_check(x);
-    y = to_ary(y);
-    if (RARRAY_LEN(y) > 0) {
-	rb_ary_splice(x, RARRAY_LEN(x), 0, y);
+    rb_ary_modify_check(ary);
+
+    if (argc == 1) {
+        rb_ary_concat(ary, argv[0]);
     }
-    return x;
+    else if (argc > 1) {
+        int i;
+        VALUE args = rb_ary_hidden_new(argc);
+        for (i = 0; i < argc; i++) {
+            rb_ary_concat(args, argv[i]);
+        }
+        ary_append(ary, args);
+    }
+
+    ary_verify(ary);
+    return ary;
 }
 
+VALUE
+rb_ary_concat(VALUE x, VALUE y)
+{
+    return ary_append(x, to_ary(y));
+}
 
 /*
  *  call-seq:
- *     ary * int     -> new_ary
- *     ary * str     -> new_string
+ *    array * n -> new_array
+ *    array * string_separator -> new_string
  *
- *  Repetition --- With a String argument, equivalent to
- *  <code>ary.join(str)</code>.
+ *  When non-negative argument \Integer +n+ is given,
+ *  returns a new \Array built by concatenating the +n+ copies of +self+:
  *
- *  Otherwise, returns a new array built by concatenating the +int+ copies of
- *  +self+.
+ *    a = ['x', 'y']
+ *    a * 3 # => ["x", "y", "x", "y", "x", "y"]
  *
+ *  When \String argument +string_separator+ is given,
+ *  equivalent to <tt>array.join(string_separator)</tt>:
  *
- *     [ 1, 2, 3 ] * 3    #=> [ 1, 2, 3, 1, 2, 3, 1, 2, 3 ]
- *     [ 1, 2, 3 ] * ","  #=> "1,2,3"
+ *    [0, [0, 1], {foo: 0}] * ', ' # => "0, 0, 1, {:foo=>0}"
  *
  */
 
@@ -3674,61 +5174,54 @@ rb_ary_times(VALUE ary, VALUE times)
 
     tmp = rb_check_string_type(times);
     if (!NIL_P(tmp)) {
-	return rb_ary_join(ary, tmp);
+        return rb_ary_join(ary, tmp);
     }
 
     len = NUM2LONG(times);
     if (len == 0) {
-	ary2 = ary_new(rb_obj_class(ary), 0);
-	goto out;
+        ary2 = ary_new(rb_cArray, 0);
+        goto out;
     }
     if (len < 0) {
-	rb_raise(rb_eArgError, "negative argument");
+        rb_raise(rb_eArgError, "negative argument");
     }
     if (ARY_MAX_SIZE/len < RARRAY_LEN(ary)) {
-	rb_raise(rb_eArgError, "argument too big");
+        rb_raise(rb_eArgError, "argument too big");
     }
     len *= RARRAY_LEN(ary);
 
-    ary2 = ary_new(rb_obj_class(ary), len);
+    ary2 = ary_new(rb_cArray, len);
     ARY_SET_LEN(ary2, len);
 
-    ptr = RARRAY_CONST_PTR(ary);
+    ptr = RARRAY_CONST_PTR_TRANSIENT(ary);
     t = RARRAY_LEN(ary);
     if (0 < t) {
-	ary_memcpy(ary2, 0, t, ptr);
-	while (t <= len/2) {
-	    ary_memcpy(ary2, t, t, RARRAY_CONST_PTR(ary2));
+        ary_memcpy(ary2, 0, t, ptr);
+        while (t <= len/2) {
+            ary_memcpy(ary2, t, t, RARRAY_CONST_PTR_TRANSIENT(ary2));
             t *= 2;
         }
         if (t < len) {
-	    ary_memcpy(ary2, t, len-t, RARRAY_CONST_PTR(ary2));
+            ary_memcpy(ary2, t, len-t, RARRAY_CONST_PTR_TRANSIENT(ary2));
         }
     }
   out:
-    OBJ_INFECT(ary2, ary);
-
     return ary2;
 }
 
 /*
  *  call-seq:
- *     ary.assoc(obj)   -> element_ary  or  nil
+ *    array.assoc(obj) -> found_array or nil
  *
- *  Searches through an array whose elements are also arrays comparing +obj+
- *  with the first element of each contained array using <code>obj.==</code>.
+ *  Returns the first element in +self+ that is an \Array
+ *  whose first element <tt>==</tt> +obj+:
  *
- *  Returns the first contained array that matches (that is, the first
- *  associated array), or +nil+ if no match is found.
+ *    a = [{foo: 0}, [2, 4], [4, 5, 6], [4, 5]]
+ *    a.assoc(4) # => [4, 5, 6]
  *
- *  See also Array#rassoc
+ *  Returns +nil+ if no such element is found.
  *
- *     s1 = [ "colors", "red", "blue", "green" ]
- *     s2 = [ "letters", "a", "b", "c" ]
- *     s3 = "foo"
- *     a  = [ s1, s2, s3 ]
- *     a.assoc("letters")  #=> [ "letters", "a", "b", "c" ]
- *     a.assoc("foo")      #=> nil
+ *  Related: #rassoc.
  */
 
 VALUE
@@ -3738,30 +5231,27 @@ rb_ary_assoc(VALUE ary, VALUE key)
     VALUE v;
 
     for (i = 0; i < RARRAY_LEN(ary); ++i) {
-	v = rb_check_array_type(RARRAY_AREF(ary, i));
-	if (!NIL_P(v) && RARRAY_LEN(v) > 0 &&
-	    rb_equal(RARRAY_AREF(v, 0), key))
-	    return v;
+        v = rb_check_array_type(RARRAY_AREF(ary, i));
+        if (!NIL_P(v) && RARRAY_LEN(v) > 0 &&
+            rb_equal(RARRAY_AREF(v, 0), key))
+            return v;
     }
     return Qnil;
 }
 
 /*
  *  call-seq:
- *     ary.rassoc(obj) -> element_ary or nil
- *
- *  Searches through the array whose elements are also arrays.
+ *    array.rassoc(obj) -> found_array or nil
  *
- *  Compares +obj+ with the second element of each contained array using
- *  <code>obj.==</code>.
+ *  Returns the first element in +self+ that is an \Array
+ *  whose second element <tt>==</tt> +obj+:
  *
- *  Returns the first contained array that matches +obj+.
+ *    a = [{foo: 0}, [2, 4], [4, 5, 6], [4, 5]]
+ *    a.rassoc(4) # => [2, 4]
  *
- *  See also Array#assoc.
+ *  Returns +nil+ if no such element is found.
  *
- *     a = [ [ 1, "one"], [2, "two"], [3, "three"], ["ii", "two"] ]
- *     a.rassoc("two")    #=> [2, "two"]
- *     a.rassoc("four")   #=> nil
+ *  Related: #assoc.
  */
 
 VALUE
@@ -3771,11 +5261,11 @@ rb_ary_rassoc(VALUE ary, VALUE value)
     VALUE v;
 
     for (i = 0; i < RARRAY_LEN(ary); ++i) {
-	v = RARRAY_AREF(ary, i);
-	if (RB_TYPE_P(v, T_ARRAY) &&
-	    RARRAY_LEN(v) > 1 &&
-	    rb_equal(RARRAY_AREF(v, 1), value))
-	    return v;
+        v = RARRAY_AREF(ary, i);
+        if (RB_TYPE_P(v, T_ARRAY) &&
+            RARRAY_LEN(v) > 1 &&
+            rb_equal(RARRAY_AREF(v, 1), value))
+            return v;
     }
     return Qnil;
 }
@@ -3788,43 +5278,48 @@ recursive_equal(VALUE ary1, VALUE ary2, int recur)
 
     if (recur) return Qtrue; /* Subtle! */
 
+    /* rb_equal() can evacuate ptrs */
     p1 = RARRAY_CONST_PTR(ary1);
     p2 = RARRAY_CONST_PTR(ary2);
     len1 = RARRAY_LEN(ary1);
 
     for (i = 0; i < len1; i++) {
-	if (*p1 != *p2) {
-	    if (rb_equal(*p1, *p2)) {
-		len1 = RARRAY_LEN(ary1);
-		if (len1 != RARRAY_LEN(ary2))
-		    return Qfalse;
-		if (len1 < i)
-		    return Qtrue;
-		p1 = RARRAY_CONST_PTR(ary1) + i;
-		p2 = RARRAY_CONST_PTR(ary2) + i;
-	    }
-	    else {
-		return Qfalse;
-	    }
-	}
-	p1++;
-	p2++;
+        if (*p1 != *p2) {
+            if (rb_equal(*p1, *p2)) {
+                len1 = RARRAY_LEN(ary1);
+                if (len1 != RARRAY_LEN(ary2))
+                    return Qfalse;
+                if (len1 < i)
+                    return Qtrue;
+                p1 = RARRAY_CONST_PTR(ary1) + i;
+                p2 = RARRAY_CONST_PTR(ary2) + i;
+            }
+            else {
+                return Qfalse;
+            }
+        }
+        p1++;
+        p2++;
     }
     return Qtrue;
 }
 
 /*
  *  call-seq:
- *     ary == other_ary   ->   bool
+ *    array == other_array -> true or false
+ *
+ *  Returns +true+ if both <tt>array.size == other_array.size</tt>
+ *  and for each index +i+ in +array+, <tt>array[i] == other_array[i]</tt>:
  *
- *  Equality --- Two arrays are equal if they contain the same number of
- *  elements and if each element is equal to (according to Object#==) the
- *  corresponding element in +other_ary+.
+ *    a0 = [:foo, 'bar', 2]
+ *    a1 = [:foo, 'bar', 2.0]
+ *    a1 == a0 # => true
+ *    [] == [] # => true
  *
- *     [ "a", "c" ]    == [ "a", "c", 7 ]     #=> false
- *     [ "a", "c", 7 ] == [ "a", "c", 7 ]     #=> true
- *     [ "a", "c", 7 ] == [ "a", "d", "f" ]   #=> false
+ *  Otherwise, returns +false+.
  *
+ *  This method is different from method Array#eql?,
+ *  which compares elements using <tt>Object#eql?</tt>.
  */
 
 static VALUE
@@ -3832,13 +5327,13 @@ rb_ary_equal(VALUE ary1, VALUE ary2)
 {
     if (ary1 == ary2) return Qtrue;
     if (!RB_TYPE_P(ary2, T_ARRAY)) {
-	if (!rb_respond_to(ary2, idTo_ary)) {
-	    return Qfalse;
-	}
-	return rb_equal(ary2, ary1);
+        if (!rb_respond_to(ary2, idTo_ary)) {
+            return Qfalse;
+        }
+        return rb_equal(ary2, ary1);
     }
     if (RARRAY_LEN(ary1) != RARRAY_LEN(ary2)) return Qfalse;
-    if (RARRAY_CONST_PTR(ary1) == RARRAY_CONST_PTR(ary2)) return Qtrue;
+    if (RARRAY_CONST_PTR_TRANSIENT(ary1) == RARRAY_CONST_PTR_TRANSIENT(ary2)) return Qtrue;
     return rb_exec_recursive_paired(recursive_equal, ary1, ary2, ary2);
 }
 
@@ -3849,18 +5344,27 @@ recursive_eql(VALUE ary1, VALUE ary2, int recur)
 
     if (recur) return Qtrue; /* Subtle! */
     for (i=0; i<RARRAY_LEN(ary1); i++) {
-	if (!rb_eql(rb_ary_elt(ary1, i), rb_ary_elt(ary2, i)))
-	    return Qfalse;
+        if (!rb_eql(rb_ary_elt(ary1, i), rb_ary_elt(ary2, i)))
+            return Qfalse;
     }
     return Qtrue;
 }
 
 /*
  *  call-seq:
- *     ary.eql?(other)  -> true or false
+ *    array.eql? other_array -> true or false
+ *
+ *  Returns +true+ if +self+ and +other_array+ are the same size,
+ *  and if, for each index +i+ in +self+, <tt>self[i].eql? other_array[i]</tt>:
+ *
+ *    a0 = [:foo, 'bar', 2]
+ *    a1 = [:foo, 'bar', 2]
+ *    a1.eql?(a0) # => true
  *
- *  Returns +true+ if +self+ and +other+ are the same object,
- *  or are both arrays with the same content (according to Object#eql?).
+ *  Otherwise, returns +false+.
+ *
+ *  This method is different from method Array#==,
+ *  which compares using method <tt>Object#==</tt>.
  */
 
 static VALUE
@@ -3869,20 +5373,21 @@ rb_ary_eql(VALUE ary1, VALUE ary2)
     if (ary1 == ary2) return Qtrue;
     if (!RB_TYPE_P(ary2, T_ARRAY)) return Qfalse;
     if (RARRAY_LEN(ary1) != RARRAY_LEN(ary2)) return Qfalse;
-    if (RARRAY_CONST_PTR(ary1) == RARRAY_CONST_PTR(ary2)) return Qtrue;
+    if (RARRAY_CONST_PTR_TRANSIENT(ary1) == RARRAY_CONST_PTR_TRANSIENT(ary2)) return Qtrue;
     return rb_exec_recursive_paired(recursive_eql, ary1, ary2, ary2);
 }
 
 /*
  *  call-seq:
- *     ary.hash   -> fixnum
+ *    array.hash -> integer
+ *
+ *  Returns the integer hash value for +self+.
  *
- *  Compute a hash-code for this array.
+ *  Two arrays with the same content will have the same hash code (and will compare using eql?):
  *
- *  Two arrays with the same content will have the same hash code (and will
- *  compare using #eql?).
+ *    [0, 1, 2].hash == [0, 1, 2].hash # => true
+ *    [0, 1, 2].hash == [0, 1, 3].hash # => false
  *
- *  See also Object#hash.
  */
 
 static VALUE
@@ -3895,23 +5400,22 @@ rb_ary_hash(VALUE ary)
     h = rb_hash_start(RARRAY_LEN(ary));
     h = rb_hash_uint(h, (st_index_t)rb_ary_hash);
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	n = rb_hash(RARRAY_AREF(ary, i));
-	h = rb_hash_uint(h, NUM2LONG(n));
+        n = rb_hash(RARRAY_AREF(ary, i));
+        h = rb_hash_uint(h, NUM2LONG(n));
     }
     h = rb_hash_end(h);
-    return LONG2FIX(h);
+    return ST2FIX(h);
 }
 
 /*
  *  call-seq:
- *     ary.include?(object)   -> true or false
+ *    array.include?(obj) -> true or false
  *
- *  Returns +true+ if the given +object+ is present in +self+ (that is, if any
- *  element <code>==</code> +object+), otherwise returns +false+.
+ *  Returns +true+ if for some index +i+ in +self+, <tt>obj == self[i]</tt>;
+ *  otherwise +false+:
  *
- *     a = [ "a", "b", "c" ]
- *     a.include?("b")   #=> true
- *     a.include?("z")   #=> false
+ *    [0, 1, 2].include?(2) # => true
+ *    [0, 1, 2].include?(3) # => false
  */
 
 VALUE
@@ -3921,18 +5425,28 @@ rb_ary_includes(VALUE ary, VALUE item)
     VALUE e;
 
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	e = RARRAY_AREF(ary, i);
-	switch (rb_equal_opt(e, item)) {
-	  case Qundef:
-	    if (rb_equal(e, item)) return Qtrue;
-	    break;
-	  case Qtrue:
-	    return Qtrue;
-	}
+        e = RARRAY_AREF(ary, i);
+        if (rb_equal(e, item)) {
+            return Qtrue;
+        }
     }
     return Qfalse;
 }
 
+static VALUE
+rb_ary_includes_by_eql(VALUE ary, VALUE item)
+{
+    long i;
+    VALUE e;
+
+    for (i=0; i<RARRAY_LEN(ary); i++) {
+        e = RARRAY_AREF(ary, i);
+        if (rb_eql(item, e)) {
+            return Qtrue;
+        }
+    }
+    return Qfalse;
+}
 
 static VALUE
 recursive_cmp(VALUE ary1, VALUE ary2, int recur)
@@ -3942,45 +5456,46 @@ recursive_cmp(VALUE ary1, VALUE ary2, int recur)
     if (recur) return Qundef;	/* Subtle! */
     len = RARRAY_LEN(ary1);
     if (len > RARRAY_LEN(ary2)) {
-	len = RARRAY_LEN(ary2);
+        len = RARRAY_LEN(ary2);
     }
     for (i=0; i<len; i++) {
-	VALUE e1 = rb_ary_elt(ary1, i), e2 = rb_ary_elt(ary2, i);
-	VALUE v = rb_funcallv(e1, id_cmp, 1, &e2);
-	if (v != INT2FIX(0)) {
-	    return v;
-	}
+        VALUE e1 = rb_ary_elt(ary1, i), e2 = rb_ary_elt(ary2, i);
+        VALUE v = rb_funcallv(e1, id_cmp, 1, &e2);
+        if (v != INT2FIX(0)) {
+            return v;
+        }
     }
     return Qundef;
 }
 
 /*
  *  call-seq:
- *     ary <=> other_ary   ->  -1, 0, +1 or nil
+ *    array <=> other_array -> -1, 0, or 1
+ *
+ *  Returns -1, 0, or 1 as +self+ is less than, equal to, or greater than +other_array+.
+ *  For each index +i+ in +self+, evaluates <tt>result = self[i] <=> other_array[i]</tt>.
  *
- *  Comparison --- Returns an integer (+-1+, +0+, or <code>+1</code>) if this
- *  array is less than, equal to, or greater than +other_ary+.
+ *  Returns -1 if any result is -1:
  *
- *  Each object in each array is compared (using the <=> operator).
+ *    [0, 1, 2] <=> [0, 1, 3] # => -1
  *
- *  Arrays are compared in an "element-wise" manner; the first element of +ary+
- *  is compared with the first one of +other_ary+ using the <=> operator, then
- *  each of the second elements, etc...
- *  As soon as the result of any such comparison is non zero (i.e. the two
- *  corresponding elements are not equal), that result is returned for the
- *  whole array comparison.
+ *  Returns 1 if any result is 1:
  *
- *  If all the elements are equal, then the result is based on a comparison of
- *  the array lengths. Thus, two arrays are "equal" according to Array#<=> if,
- *  and only if, they have the same length and the value of each element is
- *  equal to the value of the corresponding element in the other array.
+ *    [0, 1, 2] <=> [0, 1, 1] # => 1
  *
- *  +nil+ is returned if the +other_ary+ is not an array or if the comparison
- *  of two elements returned +nil+.
+ *  When all results are zero:
  *
- *     [ "a", "a", "c" ]    <=> [ "a", "b", "c" ]   #=> -1
- *     [ 1, 2, 3, 4, 5, 6 ] <=> [ 1, 2 ]            #=> +1
- *     [ 1, 2 ]             <=> [ 1, :two ]         #=> nil
+ *  - Returns -1 if +array+ is smaller than +other_array+:
+ *
+ *      [0, 1, 2] <=> [0, 1, 2, 3] # => -1
+ *
+ *  - Returns 1 if +array+ is larger than +other_array+:
+ *
+ *      [0, 1, 2] <=> [0, 1] # => 1
+ *
+ *  - Returns 0 if +array+ and +other_array+ are the same size:
+ *
+ *      [0, 1, 2] <=> [0, 1, 2] # => 0
  *
  */
 
@@ -3994,7 +5509,7 @@ rb_ary_cmp(VALUE ary1, VALUE ary2)
     if (NIL_P(ary2)) return Qnil;
     if (ary1 == ary2) return INT2FIX(0);
     v = rb_exec_recursive_paired(recursive_cmp, ary1, ary2, ary2);
-    if (v != Qundef) return v;
+    if (!UNDEF_P(v)) return v;
     len = RARRAY_LEN(ary1) - RARRAY_LEN(ary2);
     if (len == 0) return INT2FIX(0);
     if (len > 0) return INT2FIX(1);
@@ -4007,18 +5522,17 @@ ary_add_hash(VALUE hash, VALUE ary)
     long i;
 
     for (i=0; i<RARRAY_LEN(ary); i++) {
-	VALUE elt = RARRAY_AREF(ary, i);
-	if (rb_hash_lookup2(hash, elt, Qundef) == Qundef) {
-	    rb_hash_aset(hash, elt, elt);
-	}
+        VALUE elt = RARRAY_AREF(ary, i);
+        rb_hash_add_new_element(hash, elt, elt);
     }
     return hash;
 }
 
 static inline VALUE
-ary_tmp_hash_new(void)
+ary_tmp_hash_new(VALUE ary)
 {
-    VALUE hash = rb_hash_new();
+    long size = RARRAY_LEN(ary);
+    VALUE hash = rb_hash_new_with_size(size);
 
     RBASIC_CLEAR_CLASS(hash);
     return hash;
@@ -4027,7 +5541,7 @@ ary_tmp_hash_new(void)
 static VALUE
 ary_make_hash(VALUE ary)
 {
-    VALUE hash = ary_tmp_hash_new();
+    VALUE hash = ary_tmp_hash_new(ary);
     return ary_add_hash(hash, ary);
 }
 
@@ -4037,10 +5551,8 @@ ary_add_hash_by(VALUE hash, VALUE ary)
     long i;
 
     for (i = 0; i < RARRAY_LEN(ary); ++i) {
-	VALUE v = rb_ary_elt(ary, i), k = rb_yield(v);
-	if (rb_hash_lookup2(hash, k, Qundef) == Qundef) {
-	    rb_hash_aset(hash, k, v);
-	}
+        VALUE v = rb_ary_elt(ary, i), k = rb_yield(v);
+        rb_hash_add_new_element(hash, k, v);
     }
     return hash;
 }
@@ -4048,51 +5560,61 @@ ary_add_hash_by(VALUE hash, VALUE ary)
 static VALUE
 ary_make_hash_by(VALUE ary)
 {
-    VALUE hash = ary_tmp_hash_new();
+    VALUE hash = ary_tmp_hash_new(ary);
     return ary_add_hash_by(hash, ary);
 }
 
 static inline void
 ary_recycle_hash(VALUE hash)
 {
-    if (RHASH(hash)->ntbl) {
-	st_table *tbl = RHASH(hash)->ntbl;
-	RHASH(hash)->ntbl = 0;
-	st_free_table(tbl);
+    assert(RBASIC_CLASS(hash) == 0);
+    if (RHASH_ST_TABLE_P(hash)) {
+        st_table *tbl = RHASH_ST_TABLE(hash);
+        st_free_table(tbl);
+        RHASH_ST_CLEAR(hash);
     }
-    RB_GC_GUARD(hash);
 }
 
 /*
  *  call-seq:
- *     ary - other_ary    -> new_ary
- *
- *  Array Difference
- *
- *  Returns a new array that is a copy of the original array, removing any
- *  items that also appear in +other_ary+. The order is preserved from the
- *  original array.
+ *    array - other_array -> new_array
  *
- *  It compares elements using their #hash and #eql? methods for efficiency.
+ *  Returns a new \Array containing only those elements from +array+
+ *  that are not found in \Array +other_array+;
+ *  items are compared using <tt>eql?</tt>;
+ *  the order from +array+ is preserved:
  *
- *     [ 1, 1, 2, 2, 3, 3, 4, 5 ] - [ 1, 2, 4 ]  #=>  [ 3, 3, 5 ]
+ *    [0, 1, 1, 2, 1, 1, 3, 1, 1] - [1] # => [0, 2, 3]
+ *    [0, 1, 2, 3] - [3, 0] # => [1, 2]
+ *    [0, 1, 2] - [4] # => [0, 1, 2]
  *
- *  If you need set-like behavior, see the library class Set.
+ *  Related: Array#difference.
  */
 
-static VALUE
+VALUE
 rb_ary_diff(VALUE ary1, VALUE ary2)
 {
     VALUE ary3;
     VALUE hash;
     long i;
 
-    hash = ary_make_hash(to_ary(ary2));
+    ary2 = to_ary(ary2);
+    if (RARRAY_LEN(ary2) == 0) { return ary_make_shared_copy(ary1); }
     ary3 = rb_ary_new();
 
+    if (RARRAY_LEN(ary1) <= SMALL_ARRAY_LEN || RARRAY_LEN(ary2) <= SMALL_ARRAY_LEN) {
+        for (i=0; i<RARRAY_LEN(ary1); i++) {
+            VALUE elt = rb_ary_elt(ary1, i);
+            if (rb_ary_includes_by_eql(ary2, elt)) continue;
+            rb_ary_push(ary3, elt);
+        }
+        return ary3;
+    }
+
+    hash = ary_make_hash(ary2);
     for (i=0; i<RARRAY_LEN(ary1); i++) {
-	if (st_lookup(rb_hash_tbl_raw(hash), RARRAY_AREF(ary1, i), 0)) continue;
-	rb_ary_push(ary3, rb_ary_elt(ary1, i));
+        if (rb_hash_stlike_lookup(hash, RARRAY_AREF(ary1, i), NULL)) continue;
+        rb_ary_push(ary3, rb_ary_elt(ary1, i));
     }
     ary_recycle_hash(hash);
     return ary3;
@@ -4100,17 +5622,73 @@ rb_ary_diff(VALUE ary1, VALUE ary2)
 
 /*
  *  call-seq:
- *     ary & other_ary      -> new_ary
+ *    array.difference(*other_arrays) -> new_array
  *
- *  Set Intersection --- Returns a new array containing unique elements common to the
- *  two arrays. The order is preserved from the original array.
+ *  Returns a new \Array containing only those elements from +self+
+ *  that are not found in any of the Arrays +other_arrays+;
+ *  items are compared using <tt>eql?</tt>;  order from +self+ is preserved:
  *
- *  It compares elements using their #hash and #eql? methods for efficiency.
+ *    [0, 1, 1, 2, 1, 1, 3, 1, 1].difference([1]) # => [0, 2, 3]
+ *    [0, 1, 2, 3].difference([3, 0], [1, 3]) # => [2]
+ *    [0, 1, 2].difference([4]) # => [0, 1, 2]
  *
- *     [ 1, 1, 3, 5 ] & [ 3, 2, 1 ]                 #=> [ 1, 3 ]
- *     [ 'a', 'b', 'b', 'z' ] & [ 'a', 'b', 'c' ]   #=> [ 'a', 'b' ]
+ *  Returns a copy of +self+ if no arguments given.
  *
- *  See also Array#uniq.
+ *  Related: Array#-.
+ */
+
+static VALUE
+rb_ary_difference_multi(int argc, VALUE *argv, VALUE ary)
+{
+    VALUE ary_diff;
+    long i, length;
+    volatile VALUE t0;
+    bool *is_hash = ALLOCV_N(bool, t0, argc);
+    ary_diff = rb_ary_new();
+    length = RARRAY_LEN(ary);
+
+    for (i = 0; i < argc; i++) {
+        argv[i] = to_ary(argv[i]);
+        is_hash[i] = (length > SMALL_ARRAY_LEN && RARRAY_LEN(argv[i]) > SMALL_ARRAY_LEN);
+        if (is_hash[i]) argv[i] = ary_make_hash(argv[i]);
+    }
+
+    for (i = 0; i < RARRAY_LEN(ary); i++) {
+        int j;
+        VALUE elt = rb_ary_elt(ary, i);
+        for (j = 0; j < argc; j++) {
+            if (is_hash[j]) {
+                if (rb_hash_stlike_lookup(argv[j], RARRAY_AREF(ary, i), NULL))
+                    break;
+            }
+            else {
+                if (rb_ary_includes_by_eql(argv[j], elt)) break;
+            }
+        }
+        if (j == argc) rb_ary_push(ary_diff, elt);
+    }
+
+    ALLOCV_END(t0);
+
+    return ary_diff;
+}
+
+
+/*
+ *  call-seq:
+ *    array & other_array -> new_array
+ *
+ *  Returns a new \Array containing each element found in both +array+ and \Array +other_array+;
+ *  duplicates are omitted; items are compared using <tt>eql?</tt>:
+ *
+ *    [0, 1, 2, 3] & [1, 2] # => [1, 2]
+ *    [0, 1, 0, 1] & [0, 1] # => [0, 1]
+ *
+ *  Preserves order from +array+:
+ *
+ *    [0, 1, 2] & [3, 2, 1, 0] # => [0, 1, 2]
+ *
+ *  Related: Array#intersection.
  */
 
 
@@ -4118,28 +5696,70 @@ static VALUE
 rb_ary_and(VALUE ary1, VALUE ary2)
 {
     VALUE hash, ary3, v;
-    st_table *table;
     st_data_t vv;
     long i;
 
     ary2 = to_ary(ary2);
     ary3 = rb_ary_new();
-    if (RARRAY_LEN(ary2) == 0) return ary3;
+    if (RARRAY_LEN(ary1) == 0 || RARRAY_LEN(ary2) == 0) return ary3;
+
+    if (RARRAY_LEN(ary1) <= SMALL_ARRAY_LEN && RARRAY_LEN(ary2) <= SMALL_ARRAY_LEN) {
+        for (i=0; i<RARRAY_LEN(ary1); i++) {
+            v = RARRAY_AREF(ary1, i);
+            if (!rb_ary_includes_by_eql(ary2, v)) continue;
+            if (rb_ary_includes_by_eql(ary3, v)) continue;
+            rb_ary_push(ary3, v);
+        }
+        return ary3;
+    }
+
     hash = ary_make_hash(ary2);
-    table = rb_hash_tbl_raw(hash);
 
     for (i=0; i<RARRAY_LEN(ary1); i++) {
-	v = RARRAY_AREF(ary1, i);
-	vv = (st_data_t)v;
-	if (st_delete(table, &vv, 0)) {
-	    rb_ary_push(ary3, v);
-	}
+        v = RARRAY_AREF(ary1, i);
+        vv = (st_data_t)v;
+        if (rb_hash_stlike_delete(hash, &vv, 0)) {
+            rb_ary_push(ary3, v);
+        }
     }
     ary_recycle_hash(hash);
 
     return ary3;
 }
 
+/*
+ *  call-seq:
+ *    array.intersection(*other_arrays) -> new_array
+ *
+ *  Returns a new \Array containing each element found both in +self+
+ *  and in all of the given Arrays +other_arrays+;
+ *  duplicates are omitted; items are compared using <tt>eql?</tt>:
+ *
+ *    [0, 1, 2, 3].intersection([0, 1, 2], [0, 1, 3]) # => [0, 1]
+ *    [0, 0, 1, 1, 2, 3].intersection([0, 1, 2], [0, 1, 3]) # => [0, 1]
+ *
+ *  Preserves order from +self+:
+ *
+ *    [0, 1, 2].intersection([2, 1, 0]) # => [0, 1, 2]
+ *
+ *  Returns a copy of +self+ if no arguments given.
+ *
+ *  Related: Array#&.
+ */
+
+static VALUE
+rb_ary_intersection_multi(int argc, VALUE *argv, VALUE ary)
+{
+    VALUE result = rb_ary_dup(ary);
+    int i;
+
+    for (i = 0; i < argc; i++) {
+        result = rb_ary_and(result, argv[i]);
+    }
+
+    return result;
+}
+
 static int
 ary_hash_orset(st_data_t *key, st_data_t *value, st_data_t arg, int existing)
 {
@@ -4148,36 +5768,60 @@ ary_hash_orset(st_data_t *key, st_data_t *value, st_data_t arg, int existing)
     return ST_CONTINUE;
 }
 
+static void
+rb_ary_union(VALUE ary_union, VALUE ary)
+{
+    long i;
+    for (i = 0; i < RARRAY_LEN(ary); i++) {
+        VALUE elt = rb_ary_elt(ary, i);
+        if (rb_ary_includes_by_eql(ary_union, elt)) continue;
+        rb_ary_push(ary_union, elt);
+    }
+}
+
+static void
+rb_ary_union_hash(VALUE hash, VALUE ary2)
+{
+    long i;
+    for (i = 0; i < RARRAY_LEN(ary2); i++) {
+        VALUE elt = RARRAY_AREF(ary2, i);
+        if (!rb_hash_stlike_update(hash, (st_data_t)elt, ary_hash_orset, (st_data_t)elt)) {
+            RB_OBJ_WRITTEN(hash, Qundef, elt);
+        }
+    }
+}
+
 /*
  *  call-seq:
- *     ary | other_ary     -> new_ary
- *
- *  Set Union --- Returns a new array by joining +ary+ with +other_ary+,
- *  excluding any duplicates and preserving the order from the given arrays.
+ *    array | other_array -> new_array
  *
- *  It compares elements using their #hash and #eql? methods for efficiency.
+ *  Returns the union of +array+ and \Array +other_array+;
+ *  duplicates are removed; order is preserved;
+ *  items are compared using <tt>eql?</tt>:
  *
- *     [ "a", "b", "c" ] | [ "c", "d", "a" ]    #=> [ "a", "b", "c", "d" ]
- *     [ "c", "d", "a" ] | [ "a", "b", "c" ]    #=> [ "c", "d", "a", "b" ]
+ *    [0, 1] | [2, 3] # => [0, 1, 2, 3]
+ *    [0, 1, 1] | [2, 2, 3] # => [0, 1, 2, 3]
+ *    [0, 1, 2] | [3, 2, 1, 0] # => [0, 1, 2, 3]
  *
- *  See also Array#uniq.
+ *  Related: Array#union.
  */
 
 static VALUE
 rb_ary_or(VALUE ary1, VALUE ary2)
 {
     VALUE hash, ary3;
-    long i;
 
     ary2 = to_ary(ary2);
+    if (RARRAY_LEN(ary1) + RARRAY_LEN(ary2) <= SMALL_ARRAY_LEN) {
+        ary3 = rb_ary_new();
+        rb_ary_union(ary3, ary1);
+        rb_ary_union(ary3, ary2);
+        return ary3;
+    }
+
     hash = ary_make_hash(ary1);
+    rb_ary_union_hash(hash, ary2);
 
-    for (i=0; i<RARRAY_LEN(ary2); i++) {
-	VALUE elt = RARRAY_AREF(ary2, i);
-	if (!st_update(RHASH_TBL_RAW(hash), (st_data_t)elt, ary_hash_orset, (st_data_t)elt)) {
-	    RB_OBJ_WRITTEN(hash, Qundef, elt);
-	}
-    }
     ary3 = rb_hash_values(hash);
     ary_recycle_hash(hash);
     return ary3;
@@ -4185,114 +5829,474 @@ rb_ary_or(VALUE ary1, VALUE ary2)
 
 /*
  *  call-seq:
- *     ary.max                     -> obj
- *     ary.max { |a, b| block }    -> obj
- *     ary.max(n)                  -> array
- *     ary.max(n) { |a, b| block } -> array
+ *    array.union(*other_arrays) -> new_array
+ *
+ *  Returns a new \Array that is the union of +self+ and all given Arrays +other_arrays+;
+ *  duplicates are removed;  order is preserved;  items are compared using <tt>eql?</tt>:
+ *
+ *    [0, 1, 2, 3].union([4, 5], [6, 7]) # => [0, 1, 2, 3, 4, 5, 6, 7]
+ *    [0, 1, 1].union([2, 1], [3, 1]) # => [0, 1, 2, 3]
+ *    [0, 1, 2, 3].union([3, 2], [1, 0]) # => [0, 1, 2, 3]
+ *
+ *  Returns a copy of +self+ if no arguments given.
+ *
+ *  Related: Array#|.
+ */
+
+static VALUE
+rb_ary_union_multi(int argc, VALUE *argv, VALUE ary)
+{
+    int i;
+    long sum;
+    VALUE hash, ary_union;
+
+    sum = RARRAY_LEN(ary);
+    for (i = 0; i < argc; i++) {
+        argv[i] = to_ary(argv[i]);
+        sum += RARRAY_LEN(argv[i]);
+    }
+
+    if (sum <= SMALL_ARRAY_LEN) {
+        ary_union = rb_ary_new();
+
+        rb_ary_union(ary_union, ary);
+        for (i = 0; i < argc; i++) rb_ary_union(ary_union, argv[i]);
+
+        return ary_union;
+    }
+
+    hash = ary_make_hash(ary);
+    for (i = 0; i < argc; i++) rb_ary_union_hash(hash, argv[i]);
+
+    ary_union = rb_hash_values(hash);
+    ary_recycle_hash(hash);
+    return ary_union;
+}
+
+/*
+ *  call-seq:
+ *     ary.intersect?(other_ary)   -> true or false
+ *
+ *  Returns +true+ if the array and +other_ary+ have at least one element in
+ *  common, otherwise returns +false+:
+ *
+ *     a = [ 1, 2, 3 ]
+ *     b = [ 3, 4, 5 ]
+ *     c = [ 5, 6, 7 ]
+ *     a.intersect?(b)   #=> true
+ *     a.intersect?(c)   #=> false
+ *
+ */
+
+static VALUE
+rb_ary_intersect_p(VALUE ary1, VALUE ary2)
+{
+    VALUE hash, v, result, shorter, longer;
+    st_data_t vv;
+    long i;
+
+    ary2 = to_ary(ary2);
+    if (RARRAY_LEN(ary1) == 0 || RARRAY_LEN(ary2) == 0) return Qfalse;
+
+    if (RARRAY_LEN(ary1) <= SMALL_ARRAY_LEN && RARRAY_LEN(ary2) <= SMALL_ARRAY_LEN) {
+        for (i=0; i<RARRAY_LEN(ary1); i++) {
+            v = RARRAY_AREF(ary1, i);
+            if (rb_ary_includes_by_eql(ary2, v)) return Qtrue;
+        }
+        return Qfalse;
+    }
+
+    shorter = ary1;
+    longer = ary2;
+    if (RARRAY_LEN(ary1) > RARRAY_LEN(ary2)) {
+        longer = ary1;
+        shorter = ary2;
+    }
+
+    hash = ary_make_hash(shorter);
+    result = Qfalse;
+
+    for (i=0; i<RARRAY_LEN(longer); i++) {
+        v = RARRAY_AREF(longer, i);
+        vv = (st_data_t)v;
+        if (rb_hash_stlike_lookup(hash, vv, 0)) {
+            result = Qtrue;
+            break;
+        }
+    }
+    ary_recycle_hash(hash);
+
+    return result;
+}
+
+static VALUE
+ary_max_generic(VALUE ary, long i, VALUE vmax)
+{
+    RUBY_ASSERT(i > 0 && i < RARRAY_LEN(ary));
+
+    VALUE v;
+    for (; i < RARRAY_LEN(ary); ++i) {
+        v = RARRAY_AREF(ary, i);
+
+        if (rb_cmpint(rb_funcallv(vmax, id_cmp, 1, &v), vmax, v) < 0) {
+            vmax = v;
+        }
+    }
+
+    return vmax;
+}
+
+static VALUE
+ary_max_opt_fixnum(VALUE ary, long i, VALUE vmax)
+{
+    const long n = RARRAY_LEN(ary);
+    RUBY_ASSERT(i > 0 && i < n);
+    RUBY_ASSERT(FIXNUM_P(vmax));
+
+    VALUE v;
+    for (; i < n; ++i) {
+        v = RARRAY_AREF(ary, i);
+
+        if (FIXNUM_P(v)) {
+            if ((long)vmax < (long)v) {
+                vmax = v;
+            }
+        }
+        else {
+            return ary_max_generic(ary, i, vmax);
+        }
+    }
+
+    return vmax;
+}
+
+static VALUE
+ary_max_opt_float(VALUE ary, long i, VALUE vmax)
+{
+    const long n = RARRAY_LEN(ary);
+    RUBY_ASSERT(i > 0 && i < n);
+    RUBY_ASSERT(RB_FLOAT_TYPE_P(vmax));
+
+    VALUE v;
+    for (; i < n; ++i) {
+        v = RARRAY_AREF(ary, i);
+
+        if (RB_FLOAT_TYPE_P(v)) {
+            if (rb_float_cmp(vmax, v) < 0) {
+                vmax = v;
+            }
+        }
+        else {
+            return ary_max_generic(ary, i, vmax);
+        }
+    }
+
+    return vmax;
+}
+
+static VALUE
+ary_max_opt_string(VALUE ary, long i, VALUE vmax)
+{
+    const long n = RARRAY_LEN(ary);
+    RUBY_ASSERT(i > 0 && i < n);
+    RUBY_ASSERT(STRING_P(vmax));
+
+    VALUE v;
+    for (; i < n; ++i) {
+        v = RARRAY_AREF(ary, i);
+
+        if (STRING_P(v)) {
+            if (rb_str_cmp(vmax, v) < 0) {
+                vmax = v;
+            }
+        }
+        else {
+            return ary_max_generic(ary, i, vmax);
+        }
+    }
+
+    return vmax;
+}
+
+/*
+ *  call-seq:
+ *    array.max -> element
+ *    array.max {|a, b| ... } -> element
+ *    array.max(n) -> new_array
+ *    array.max(n) {|a, b| ... } -> new_array
+ *
+ *  Returns one of the following:
+ *
+ *  - The maximum-valued element from +self+.
+ *  - A new \Array of maximum-valued elements selected from +self+.
+ *
+ *  When no block is given, each element in +self+ must respond to method <tt><=></tt>
+ *  with an \Integer.
+ *
+ *  With no argument and no block, returns the element in +self+
+ *  having the maximum value per method <tt><=></tt>:
  *
- *  Returns the object in _ary_ with the maximum value. The
- *  first form assumes all objects implement <code>Comparable</code>;
- *  the second uses the block to return <em>a <=> b</em>.
+ *    [0, 1, 2].max # => 2
  *
- *     a = %w(albatross dog horse)
- *     a.max                                   #=> "horse"
- *     a.max { |a, b| a.length <=> b.length }  #=> "albatross"
+ *  With an argument \Integer +n+ and no block, returns a new \Array with at most +n+ elements,
+ *  in descending order per method <tt><=></tt>:
  *
- *  If the +n+ argument is given, maximum +n+ elements are returned
- *  as an array.
+ *    [0, 1, 2, 3].max(3) # => [3, 2, 1]
+ *    [0, 1, 2, 3].max(6) # => [3, 2, 1, 0]
+ *
+ *  When a block is given, the block must return an \Integer.
+ *
+ *  With a block and no argument, calls the block <tt>self.size-1</tt> times to compare elements;
+ *  returns the element having the maximum value per the block:
+ *
+ *    ['0', '00', '000'].max {|a, b| a.size <=> b.size } # => "000"
+ *
+ *  With an argument +n+ and a block, returns a new \Array with at most +n+ elements,
+ *  in descending order per the block:
+ *
+ *    ['0', '00', '000'].max(2) {|a, b| a.size <=> b.size } # => ["000", "00"]
  *
- *     a = %w[albatross dog horse]
- *     a.max(2)                                  #=> ["horse", "dog"]
- *     a.max(2) {|a, b| a.length <=> b.length }  #=> ["albatross", "horse"]
  */
 static VALUE
 rb_ary_max(int argc, VALUE *argv, VALUE ary)
 {
-    struct cmp_opt_data cmp_opt = { 0, 0 };
     VALUE result = Qundef, v;
     VALUE num;
     long i;
 
-    rb_scan_args(argc, argv, "01", &num);
-
-    if (!NIL_P(num))
+    if (rb_check_arity(argc, 0, 1) && !NIL_P(num = argv[0]))
        return rb_nmin_run(ary, num, 0, 1, 1);
 
+    const long n = RARRAY_LEN(ary);
     if (rb_block_given_p()) {
-	for (i = 0; i < RARRAY_LEN(ary); i++) {
-	   v = RARRAY_AREF(ary, i);
-	   if (result == Qundef || rb_cmpint(rb_yield_values(2, v, result), v, result) > 0) {
-	       result = v;
-	   }
-	}
+        for (i = 0; i < RARRAY_LEN(ary); i++) {
+           v = RARRAY_AREF(ary, i);
+           if (UNDEF_P(result) || rb_cmpint(rb_yield_values(2, v, result), v, result) > 0) {
+               result = v;
+           }
+        }
     }
-    else {
-	for (i = 0; i < RARRAY_LEN(ary); i++) {
-	   v = RARRAY_AREF(ary, i);
-	   if (result == Qundef || OPTIMIZED_CMP(v, result, cmp_opt) > 0) {
-	       result = v;
-	   }
-	}
-    }
-    if (result == Qundef) return Qnil;
+    else if (n > 0) {
+        result = RARRAY_AREF(ary, 0);
+        if (n > 1) {
+            if (FIXNUM_P(result) && CMP_OPTIMIZABLE(INTEGER)) {
+                return ary_max_opt_fixnum(ary, 1, result);
+            }
+            else if (STRING_P(result) && CMP_OPTIMIZABLE(STRING)) {
+                return ary_max_opt_string(ary, 1, result);
+            }
+            else if (RB_FLOAT_TYPE_P(result) && CMP_OPTIMIZABLE(FLOAT)) {
+                return ary_max_opt_float(ary, 1, result);
+            }
+            else {
+                return ary_max_generic(ary, 1, result);
+            }
+        }
+    }
+    if (UNDEF_P(result)) return Qnil;
     return result;
 }
 
+static VALUE
+ary_min_generic(VALUE ary, long i, VALUE vmin)
+{
+    RUBY_ASSERT(i > 0 && i < RARRAY_LEN(ary));
+
+    VALUE v;
+    for (; i < RARRAY_LEN(ary); ++i) {
+        v = RARRAY_AREF(ary, i);
+
+        if (rb_cmpint(rb_funcallv(vmin, id_cmp, 1, &v), vmin, v) > 0) {
+            vmin = v;
+        }
+    }
+
+    return vmin;
+}
+
+static VALUE
+ary_min_opt_fixnum(VALUE ary, long i, VALUE vmin)
+{
+    const long n = RARRAY_LEN(ary);
+    RUBY_ASSERT(i > 0 && i < n);
+    RUBY_ASSERT(FIXNUM_P(vmin));
+
+    VALUE a;
+    for (; i < n; ++i) {
+        a = RARRAY_AREF(ary, i);
+
+        if (FIXNUM_P(a)) {
+            if ((long)vmin > (long)a) {
+                vmin = a;
+            }
+        }
+        else {
+            return ary_min_generic(ary, i, vmin);
+        }
+    }
+
+    return vmin;
+}
+
+static VALUE
+ary_min_opt_float(VALUE ary, long i, VALUE vmin)
+{
+    const long n = RARRAY_LEN(ary);
+    RUBY_ASSERT(i > 0 && i < n);
+    RUBY_ASSERT(RB_FLOAT_TYPE_P(vmin));
+
+    VALUE a;
+    for (; i < n; ++i) {
+        a = RARRAY_AREF(ary, i);
+
+        if (RB_FLOAT_TYPE_P(a)) {
+            if (rb_float_cmp(vmin, a) > 0) {
+                vmin = a;
+            }
+        }
+        else {
+            return ary_min_generic(ary, i, vmin);
+        }
+    }
+
+    return vmin;
+}
+
+static VALUE
+ary_min_opt_string(VALUE ary, long i, VALUE vmin)
+{
+    const long n = RARRAY_LEN(ary);
+    RUBY_ASSERT(i > 0 && i < n);
+    RUBY_ASSERT(STRING_P(vmin));
+
+    VALUE a;
+    for (; i < n; ++i) {
+        a = RARRAY_AREF(ary, i);
+
+        if (STRING_P(a)) {
+            if (rb_str_cmp(vmin, a) > 0) {
+                vmin = a;
+            }
+        }
+        else {
+            return ary_min_generic(ary, i, vmin);
+        }
+    }
+
+    return vmin;
+}
+
 /*
  *  call-seq:
- *     ary.min                     -> obj
- *     ary.min {| a,b | block }    -> obj
- *     ary.min(n)                  -> array
- *     ary.min(n) {| a,b | block } -> array
+ *    array.min -> element
+ *    array.min { |a, b| ... } -> element
+ *    array.min(n) -> new_array
+ *    array.min(n) { |a, b| ... } -> new_array
  *
- *  Returns the object in _ary_ with the minimum value. The
- *  first form assumes all objects implement <code>Comparable</code>;
- *  the second uses the block to return <em>a <=> b</em>.
+ *  Returns one of the following:
  *
- *     a = %w(albatross dog horse)
- *     a.min                                   #=> "albatross"
- *     a.min { |a, b| a.length <=> b.length }  #=> "dog"
+ *  - The minimum-valued element from +self+.
+ *  - A new \Array of minimum-valued elements selected from +self+.
  *
- *  If the +n+ argument is given, minimum +n+ elements are returned
- *  as an array.
+ *  When no block is given, each element in +self+ must respond to method <tt><=></tt>
+ *  with an \Integer.
+ *
+ *  With no argument and no block, returns the element in +self+
+ *  having the minimum value per method <tt><=></tt>:
+ *
+ *    [0, 1, 2].min # => 0
+ *
+ *  With \Integer argument +n+ and no block, returns a new \Array with at most +n+ elements,
+ *  in ascending order per method <tt><=></tt>:
+ *
+ *    [0, 1, 2, 3].min(3) # => [0, 1, 2]
+ *    [0, 1, 2, 3].min(6) # => [0, 1, 2, 3]
+ *
+ *  When a block is given, the block must return an Integer.
+ *
+ *  With a block and no argument, calls the block <tt>self.size-1</tt> times to compare elements;
+ *  returns the element having the minimum value per the block:
+ *
+ *    ['0', '00', '000'].min { |a, b| a.size <=> b.size } # => "0"
+ *
+ *  With an argument +n+ and a block, returns a new \Array with at most +n+ elements,
+ *  in ascending order per the block:
+ *
+ *    ['0', '00', '000'].min(2) {|a, b| a.size <=> b.size } # => ["0", "00"]
  *
- *     a = %w[albatross dog horse]
- *     a.min(2)                                  #=> ["albatross", "dog"]
- *     a.min(2) {|a, b| a.length <=> b.length }  #=> ["dog", "horse"]
  */
 static VALUE
 rb_ary_min(int argc, VALUE *argv, VALUE ary)
 {
-    struct cmp_opt_data cmp_opt = { 0, 0 };
     VALUE result = Qundef, v;
     VALUE num;
     long i;
 
-    rb_scan_args(argc, argv, "01", &num);
-
-    if (!NIL_P(num))
+    if (rb_check_arity(argc, 0, 1) && !NIL_P(num = argv[0]))
        return rb_nmin_run(ary, num, 0, 0, 1);
 
+    const long n = RARRAY_LEN(ary);
     if (rb_block_given_p()) {
-	for (i = 0; i < RARRAY_LEN(ary); i++) {
-	   v = RARRAY_AREF(ary, i);
-	   if (result == Qundef || rb_cmpint(rb_yield_values(2, v, result), v, result) < 0) {
-	       result = v;
-	   }
-	}
+        for (i = 0; i < RARRAY_LEN(ary); i++) {
+           v = RARRAY_AREF(ary, i);
+           if (UNDEF_P(result) || rb_cmpint(rb_yield_values(2, v, result), v, result) < 0) {
+               result = v;
+           }
+        }
     }
-    else {
-	for (i = 0; i < RARRAY_LEN(ary); i++) {
-	   v = RARRAY_AREF(ary, i);
-	   if (result == Qundef || OPTIMIZED_CMP(v, result, cmp_opt) < 0) {
-	       result = v;
-	   }
-	}
-    }
-    if (result == Qundef) return Qnil;
+    else if (n > 0) {
+        result = RARRAY_AREF(ary, 0);
+        if (n > 1) {
+            if (FIXNUM_P(result) && CMP_OPTIMIZABLE(INTEGER)) {
+                return ary_min_opt_fixnum(ary, 1, result);
+            }
+            else if (STRING_P(result) && CMP_OPTIMIZABLE(STRING)) {
+                return ary_min_opt_string(ary, 1, result);
+            }
+            else if (RB_FLOAT_TYPE_P(result) && CMP_OPTIMIZABLE(FLOAT)) {
+                return ary_min_opt_float(ary, 1, result);
+            }
+            else {
+                return ary_min_generic(ary, 1, result);
+            }
+        }
+    }
+    if (UNDEF_P(result)) return Qnil;
     return result;
 }
 
+/*
+ *  call-seq:
+ *    array.minmax -> [min_val, max_val]
+ *    array.minmax {|a, b| ... } -> [min_val, max_val]
+ *
+ *  Returns a new 2-element \Array containing the minimum and maximum values
+ *  from +self+, either per method <tt><=></tt> or per a given block:.
+ *
+ *  When no block is given, each element in +self+ must respond to method <tt><=></tt>
+ *  with an \Integer;
+ *  returns a new 2-element \Array containing the minimum and maximum values
+ *  from +self+, per method <tt><=></tt>:
+ *
+ *    [0, 1, 2].minmax # => [0, 2]
+ *
+ *  When a block is given, the block must return an \Integer;
+ *  the block is called <tt>self.size-1</tt> times to compare elements;
+ *  returns a new 2-element \Array containing the minimum and maximum values
+ *  from +self+, per the block:
+ *
+ *    ['0', '00', '000'].minmax {|a, b| a.size <=> b.size } # => ["0", "000"]
+ *
+ */
+static VALUE
+rb_ary_minmax(VALUE ary)
+{
+    if (rb_block_given_p()) {
+        return rb_call_super(0, NULL);
+    }
+    return rb_assoc_new(rb_ary_min(0, 0, ary), rb_ary_max(0, 0, ary));
+}
+
 static int
 push_value(st_data_t key, st_data_t val, st_data_t ary)
 {
@@ -4302,31 +6306,33 @@ push_value(st_data_t key, st_data_t val, st_data_t ary)
 
 /*
  *  call-seq:
- *     ary.uniq!                -> ary or nil
- *     ary.uniq! { |item| ... } -> ary or nil
+ *    array.uniq! -> self or nil
+ *    array.uniq! {|element| ... } -> self or nil
  *
- *  Removes duplicate elements from +self+.
+ *  Removes duplicate elements from +self+, the first occurrence always being retained;
+ *  returns +self+ if any elements removed, +nil+ otherwise.
  *
- *  If a block is given, it will use the return value of the block for
- *  comparison.
+ *  With no block given, identifies and removes elements using method <tt>eql?</tt>
+ *  to compare.
  *
- *  It compares values using their #hash and #eql? methods for efficiency.
+ *  Returns +self+ if any elements removed:
  *
- *  +self+ is traversed in order, and the first occurrence is kept.
+ *    a = [0, 0, 1, 1, 2, 2]
+ *    a.uniq! # => [0, 1, 2]
  *
- *  Returns +nil+ if no changes are made (that is, no duplicates are found).
+ *  Returns +nil+ if no elements removed.
  *
- *     a = [ "a", "a", "b", "b", "c" ]
- *     a.uniq!   # => ["a", "b", "c"]
+ *  With a block given, calls the block for each element;
+ *  identifies (using method <tt>eql?</tt>) and removes
+ *  elements for which the block returns duplicate values.
  *
- *     b = [ "a", "b", "c" ]
- *     b.uniq!   # => nil
+ *  Returns +self+ if any elements removed:
  *
- *     c = [["student","sam"], ["student","george"], ["teacher","matz"]]
- *     c.uniq! { |s| s.first } # => [["student", "sam"], ["teacher", "matz"]]
+ *    a = ['a', 'aa', 'aaa', 'b', 'bb', 'bbb']
+ *    a.uniq! {|element| element.size } # => ['a', 'aa', 'aaa']
  *
+ *  Returns +nil+ if no elements removed.
  */
-
 static VALUE
 rb_ary_uniq_bang(VALUE ary)
 {
@@ -4337,22 +6343,22 @@ rb_ary_uniq_bang(VALUE ary)
     if (RARRAY_LEN(ary) <= 1)
         return Qnil;
     if (rb_block_given_p())
-	hash = ary_make_hash_by(ary);
+        hash = ary_make_hash_by(ary);
     else
-	hash = ary_make_hash(ary);
+        hash = ary_make_hash(ary);
 
     hash_size = RHASH_SIZE(hash);
     if (RARRAY_LEN(ary) == hash_size) {
-	return Qnil;
+        return Qnil;
     }
     rb_ary_modify_check(ary);
     ARY_SET_LEN(ary, 0);
     if (ARY_SHARED_P(ary) && !ARY_EMBED_P(ary)) {
-	rb_ary_unshare(ary);
-	FL_SET_EMBED(ary);
+        rb_ary_unshare(ary);
+        FL_SET_EMBED(ary);
     }
     ary_resize_capa(ary, hash_size);
-    st_foreach(rb_hash_tbl_raw(hash), push_value, ary);
+    rb_hash_foreach(hash, push_value, ary);
     ary_recycle_hash(hash);
 
     return ary;
@@ -4360,22 +6366,24 @@ rb_ary_uniq_bang(VALUE ary)
 
 /*
  *  call-seq:
- *     ary.uniq                -> new_ary
- *     ary.uniq { |item| ... } -> new_ary
+ *    array.uniq -> new_array
+ *    array.uniq {|element| ... } -> new_array
  *
- *  Returns a new array by removing duplicate values in +self+.
+ *  Returns a new \Array containing those elements from +self+ that are not duplicates,
+ *  the first occurrence always being retained.
  *
- *  If a block is given, it will use the return value of the block for comparison.
+ *  With no block given, identifies and omits duplicates using method <tt>eql?</tt>
+ *  to compare:
  *
- *  It compares values using their #hash and #eql? methods for efficiency.
+ *    a = [0, 0, 1, 1, 2, 2]
+ *    a.uniq # => [0, 1, 2]
  *
- *  +self+ is traversed in order, and the first occurrence is kept.
+ *  With a block given, calls the block for each element;
+ *  identifies (using method <tt>eql?</tt>) and omits duplicate values,
+ *  that is, those elements for which the block returns the same value:
  *
- *     a = [ "a", "a", "b", "b", "c" ]
- *     a.uniq   # => ["a", "b", "c"]
- *
- *     b = [["student","sam"], ["student","george"], ["teacher","matz"]]
- *     b.uniq { |s| s.first } # => [["student", "sam"], ["teacher", "matz"]]
+ *    a = ['a', 'aa', 'aaa', 'b', 'bb', 'bbb']
+ *    a.uniq {|element| element.size } # => ["a", "aa", "aaa"]
  *
  */
 
@@ -4384,32 +6392,32 @@ rb_ary_uniq(VALUE ary)
 {
     VALUE hash, uniq;
 
-    if (RARRAY_LEN(ary) <= 1)
-        return rb_ary_dup(ary);
-    if (rb_block_given_p()) {
-	hash = ary_make_hash_by(ary);
-	uniq = rb_hash_values(hash);
+    if (RARRAY_LEN(ary) <= 1) {
+        hash = 0;
+        uniq = rb_ary_dup(ary);
+    }
+    else if (rb_block_given_p()) {
+        hash = ary_make_hash_by(ary);
+        uniq = rb_hash_values(hash);
     }
     else {
-	hash = ary_make_hash(ary);
-	uniq = rb_hash_values(hash);
+        hash = ary_make_hash(ary);
+        uniq = rb_hash_values(hash);
+    }
+    if (hash) {
+        ary_recycle_hash(hash);
     }
-    RBASIC_SET_CLASS(uniq, rb_obj_class(ary));
-    ary_recycle_hash(hash);
 
     return uniq;
 }
 
 /*
  *  call-seq:
- *     ary.compact!    -> ary  or  nil
- *
- *  Removes +nil+ elements from the array.
+ *    array.compact! -> self or nil
  *
- *  Returns +nil+ if no changes were made, otherwise returns the array.
+ *  Removes all +nil+ elements from +self+.
  *
- *     [ "a", nil, "b", nil, "c" ].compact! #=> [ "a", "b", "c" ]
- *     [ "a", "b", "c" ].compact!           #=> nil
+ *  Returns +self+ if any elements removed, otherwise +nil+.
  */
 
 static VALUE
@@ -4419,16 +6427,16 @@ rb_ary_compact_bang(VALUE ary)
     long n;
 
     rb_ary_modify(ary);
-    p = t = (VALUE *)RARRAY_CONST_PTR(ary); /* WB: no new reference */
+    p = t = (VALUE *)RARRAY_CONST_PTR_TRANSIENT(ary); /* WB: no new reference */
     end = p + RARRAY_LEN(ary);
 
     while (t < end) {
-	if (NIL_P(*t)) t++;
-	else *p++ = *t++;
+        if (NIL_P(*t)) t++;
+        else *p++ = *t++;
     }
-    n = p - RARRAY_CONST_PTR(ary);
+    n = p - RARRAY_CONST_PTR_TRANSIENT(ary);
     if (RARRAY_LEN(ary) == n) {
-	return Qnil;
+        return Qnil;
     }
     ary_resize_smaller(ary, n);
 
@@ -4437,12 +6445,12 @@ rb_ary_compact_bang(VALUE ary)
 
 /*
  *  call-seq:
- *     ary.compact     -> new_ary
+ *    array.compact -> new_array
  *
- *  Returns a copy of +self+ with all +nil+ elements removed.
+ *  Returns a new \Array containing all non-+nil+ elements from +self+:
  *
- *     [ "a", nil, "b", nil, "c", nil ].compact
- *                       #=> [ "a", "b", "c" ]
+ *    a = [nil, 0, nil, 1, nil, 2, nil]
+ *    a.compact # => [0, 1, 2]
  */
 
 static VALUE
@@ -4455,23 +6463,29 @@ rb_ary_compact(VALUE ary)
 
 /*
  *  call-seq:
- *     ary.count                   -> int
- *     ary.count(obj)              -> int
- *     ary.count { |item| block }  -> int
+ *    array.count -> an_integer
+ *    array.count(obj) -> an_integer
+ *    array.count {|element| ... } -> an_integer
+ *
+ *  Returns a count of specified elements.
+ *
+ *  With no argument and no block, returns the count of all elements:
  *
- *  Returns the number of elements.
+ *    [0, 1, 2].count # => 3
+ *    [].count # => 0
  *
- *  If an argument is given, counts the number of elements which equal +obj+
- *  using <code>==</code>.
+ *  With argument +obj+, returns the count of elements <tt>==</tt> to +obj+:
  *
- *  If a block is given, counts the number of elements for which the block
- *  returns a true value.
+ *    [0, 1, 2, 0.0].count(0) # => 2
+ *    [0, 1, 2].count(3) # => 0
  *
- *     ary = [1, 2, 4, 2]
- *     ary.count                  #=> 4
- *     ary.count(2)               #=> 2
- *     ary.count { |x| x%2 == 0 } #=> 3
+ *  With no argument and a block given, calls the block with each element;
+ *  returns the count of elements for which the block returns a truthy value:
  *
+ *    [0, 1, 2, 3].count {|element| element > 1} # => 2
+ *
+ *  With argument +obj+ and a block given, issues a warning, ignores the block,
+ *  and returns the count of elements <tt>==</tt> to +obj+.
  */
 
 static VALUE
@@ -4479,108 +6493,152 @@ rb_ary_count(int argc, VALUE *argv, VALUE ary)
 {
     long i, n = 0;
 
-    if (argc == 0) {
-	VALUE v;
+    if (rb_check_arity(argc, 0, 1) == 0) {
+        VALUE v;
 
-	if (!rb_block_given_p())
-	    return LONG2NUM(RARRAY_LEN(ary));
+        if (!rb_block_given_p())
+            return LONG2NUM(RARRAY_LEN(ary));
 
-	for (i = 0; i < RARRAY_LEN(ary); i++) {
-	    v = RARRAY_AREF(ary, i);
-	    if (RTEST(rb_yield(v))) n++;
-	}
+        for (i = 0; i < RARRAY_LEN(ary); i++) {
+            v = RARRAY_AREF(ary, i);
+            if (RTEST(rb_yield(v))) n++;
+        }
     }
     else {
-	VALUE obj;
+        VALUE obj = argv[0];
 
-	rb_scan_args(argc, argv, "1", &obj);
-	if (rb_block_given_p()) {
-	    rb_warn("given block not used");
-	}
-	for (i = 0; i < RARRAY_LEN(ary); i++) {
-	    if (rb_equal(RARRAY_AREF(ary, i), obj)) n++;
-	}
+        if (rb_block_given_p()) {
+            rb_warn("given block not used");
+        }
+        for (i = 0; i < RARRAY_LEN(ary); i++) {
+            if (rb_equal(RARRAY_AREF(ary, i), obj)) n++;
+        }
     }
 
     return LONG2NUM(n);
 }
 
 static VALUE
-flatten(VALUE ary, int level, int *modified)
+flatten(VALUE ary, int level)
 {
-    long i = 0;
-    VALUE stack, result, tmp, elt;
-    st_table *memo;
+    long i;
+    VALUE stack, result, tmp = 0, elt, vmemo;
+    st_table *memo = 0;
     st_data_t id;
 
-    stack = ary_new(0, ARY_DEFAULT_SIZE);
+    for (i = 0; i < RARRAY_LEN(ary); i++) {
+        elt = RARRAY_AREF(ary, i);
+        tmp = rb_check_array_type(elt);
+        if (!NIL_P(tmp)) {
+            break;
+        }
+    }
+    if (i == RARRAY_LEN(ary)) {
+        return ary;
+    }
+
     result = ary_new(0, RARRAY_LEN(ary));
-    memo = st_init_numtable();
-    st_insert(memo, (st_data_t)ary, (st_data_t)Qtrue);
-    *modified = 0;
+    ary_memcpy(result, 0, i, RARRAY_CONST_PTR_TRANSIENT(ary));
+    ARY_SET_LEN(result, i);
+
+    stack = ary_new(0, ARY_DEFAULT_SIZE);
+    rb_ary_push(stack, ary);
+    rb_ary_push(stack, LONG2NUM(i + 1));
+
+    if (level < 0) {
+        vmemo = rb_hash_new();
+        RBASIC_CLEAR_CLASS(vmemo);
+        memo = st_init_numtable();
+        rb_hash_st_table_set(vmemo, memo);
+        st_insert(memo, (st_data_t)ary, (st_data_t)Qtrue);
+        st_insert(memo, (st_data_t)tmp, (st_data_t)Qtrue);
+    }
+
+    ary = tmp;
+    i = 0;
 
     while (1) {
-	while (i < RARRAY_LEN(ary)) {
-	    elt = RARRAY_AREF(ary, i++);
-	    if (level >= 0 && RARRAY_LEN(stack) / 2 >= level) {
-		rb_ary_push(result, elt);
-		continue;
-	    }
-	    tmp = rb_check_array_type(elt);
-	    if (RBASIC(result)->klass) {
-		rb_raise(rb_eRuntimeError, "flatten reentered");
-	    }
-	    if (NIL_P(tmp)) {
-		rb_ary_push(result, elt);
-	    }
-	    else {
-		*modified = 1;
-		id = (st_data_t)tmp;
-		if (st_lookup(memo, id, 0)) {
-		    st_free_table(memo);
-		    rb_raise(rb_eArgError, "tried to flatten recursive array");
-		}
-		st_insert(memo, id, (st_data_t)Qtrue);
-		rb_ary_push(stack, ary);
-		rb_ary_push(stack, LONG2NUM(i));
-		ary = tmp;
-		i = 0;
-	    }
-	}
-	if (RARRAY_LEN(stack) == 0) {
-	    break;
-	}
-	id = (st_data_t)ary;
-	st_delete(memo, &id, 0);
-	tmp = rb_ary_pop(stack);
-	i = NUM2LONG(tmp);
-	ary = rb_ary_pop(stack);
-    }
-
-    st_free_table(memo);
-
-    RBASIC_SET_CLASS(result, rb_class_of(ary));
+        while (i < RARRAY_LEN(ary)) {
+            elt = RARRAY_AREF(ary, i++);
+            if (level >= 0 && RARRAY_LEN(stack) / 2 >= level) {
+                rb_ary_push(result, elt);
+                continue;
+            }
+            tmp = rb_check_array_type(elt);
+            if (RBASIC(result)->klass) {
+                if (memo) {
+                    RB_GC_GUARD(vmemo);
+                    st_clear(memo);
+                }
+                rb_raise(rb_eRuntimeError, "flatten reentered");
+            }
+            if (NIL_P(tmp)) {
+                rb_ary_push(result, elt);
+            }
+            else {
+                if (memo) {
+                    id = (st_data_t)tmp;
+                    if (st_is_member(memo, id)) {
+                        st_clear(memo);
+                        rb_raise(rb_eArgError, "tried to flatten recursive array");
+                    }
+                    st_insert(memo, id, (st_data_t)Qtrue);
+                }
+                rb_ary_push(stack, ary);
+                rb_ary_push(stack, LONG2NUM(i));
+                ary = tmp;
+                i = 0;
+            }
+        }
+        if (RARRAY_LEN(stack) == 0) {
+            break;
+        }
+        if (memo) {
+            id = (st_data_t)ary;
+            st_delete(memo, &id, 0);
+        }
+        tmp = rb_ary_pop(stack);
+        i = NUM2LONG(tmp);
+        ary = rb_ary_pop(stack);
+    }
+
+    if (memo) {
+        st_clear(memo);
+    }
+
+    RBASIC_SET_CLASS(result, rb_cArray);
     return result;
 }
 
 /*
  *  call-seq:
- *     ary.flatten!        -> ary or nil
- *     ary.flatten!(level) -> ary or nil
+ *    array.flatten! -> self or nil
+ *    array.flatten!(level) -> self or nil
+ *
+ *  Replaces each nested \Array in +self+ with the elements from that \Array;
+ *  returns +self+ if any changes, +nil+ otherwise.
+ *
+ *  With non-negative \Integer argument +level+, flattens recursively through +level+ levels:
  *
- *  Flattens +self+ in place.
+ *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
+ *    a.flatten!(1) # => [0, 1, [2, 3], 4, 5]
+ *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
+ *    a.flatten!(2) # => [0, 1, 2, 3, 4, 5]
+ *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
+ *    a.flatten!(3) # => [0, 1, 2, 3, 4, 5]
+ *    [0, 1, 2].flatten!(1) # => nil
  *
- *  Returns +nil+ if no modifications were made (i.e., the array contains no
- *  subarrays.)
+ *  With no argument, a +nil+ argument, or with negative argument +level+, flattens all levels:
  *
- *  The optional +level+ argument determines the level of recursion to flatten.
+ *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
+ *    a.flatten! # => [0, 1, 2, 3, 4, 5]
+ *    [0, 1, 2].flatten! # => nil
+ *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
+ *    a.flatten!(-1) # => [0, 1, 2, 3, 4, 5]
+ *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
+ *    a.flatten!(-2) # => [0, 1, 2, 3, 4, 5]
+ *    [0, 1, 2].flatten!(-1) # => nil
  *
- *     a = [ 1, 2, [3, [4, 5] ] ]
- *     a.flatten!   #=> [1, 2, 3, 4, 5]
- *     a.flatten!   #=> nil
- *     a            #=> [1, 2, 3, 4, 5]
- *     a = [ 1, 2, [3, [4, 5] ] ]
- *     a.flatten!(1) #=> [1, 2, 3, [4, 5]]
  */
 
 static VALUE
@@ -4589,15 +6647,14 @@ rb_ary_flatten_bang(int argc, VALUE *argv, VALUE ary)
     int mod = 0, level = -1;
     VALUE result, lv;
 
-    rb_scan_args(argc, argv, "01", &lv);
+    lv = (rb_check_arity(argc, 0, 1) ? argv[0] : Qnil);
     rb_ary_modify_check(ary);
     if (!NIL_P(lv)) level = NUM2INT(lv);
     if (level == 0) return Qnil;
 
-    result = flatten(ary, level, &mod);
-    if (mod == 0) {
-	ary_discard(result);
-	return Qnil;
+    result = flatten(ary, level);
+    if (result == ary) {
+        return Qnil;
     }
     if (!(mod = ARY_EMBED_P(result))) rb_obj_freeze(result);
     rb_ary_replace(ary, result);
@@ -4608,246 +6665,212 @@ rb_ary_flatten_bang(int argc, VALUE *argv, VALUE ary)
 
 /*
  *  call-seq:
- *     ary.flatten -> new_ary
- *     ary.flatten(level) -> new_ary
- *
- *  Returns a new array that is a one-dimensional flattening of +self+
- *  (recursively).
- *
- *  That is, for every element that is an array, extract its elements into
- *  the new array.
- *
- *  The optional +level+ argument determines the level of recursion to
- *  flatten.
+ *    array.flatten -> new_array
+ *    array.flatten(level) -> new_array
+ *
+ *  Returns a new \Array that is a recursive flattening of +self+:
+ *  - Each non-Array element is unchanged.
+ *  - Each \Array is replaced by its individual elements.
+ *
+ *  With non-negative \Integer argument +level+, flattens recursively through +level+ levels:
+ *
+ *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
+ *    a.flatten(0) # => [0, [1, [2, 3], 4], 5]
+ *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
+ *    a.flatten(1) # => [0, 1, [2, 3], 4, 5]
+ *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
+ *    a.flatten(2) # => [0, 1, 2, 3, 4, 5]
+ *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
+ *    a.flatten(3) # => [0, 1, 2, 3, 4, 5]
+ *
+ *  With no argument, a +nil+ argument, or with negative argument +level+, flattens all levels:
+ *
+ *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
+ *    a.flatten # => [0, 1, 2, 3, 4, 5]
+ *    [0, 1, 2].flatten # => [0, 1, 2]
+ *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
+ *    a.flatten(-1) # => [0, 1, 2, 3, 4, 5]
+ *    a = [ 0, [ 1, [2, 3], 4 ], 5 ]
+ *    a.flatten(-2) # => [0, 1, 2, 3, 4, 5]
+ *    [0, 1, 2].flatten(-1) # => [0, 1, 2]
  *
- *     s = [ 1, 2, 3 ]           #=> [1, 2, 3]
- *     t = [ 4, 5, 6, [7, 8] ]   #=> [4, 5, 6, [7, 8]]
- *     a = [ s, t, 9, 10 ]       #=> [[1, 2, 3], [4, 5, 6, [7, 8]], 9, 10]
- *     a.flatten                 #=> [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
- *     a = [ 1, 2, [3, [4, 5] ] ]
- *     a.flatten(1)              #=> [1, 2, 3, [4, 5]]
  */
 
 static VALUE
 rb_ary_flatten(int argc, VALUE *argv, VALUE ary)
 {
-    int mod = 0, level = -1;
-    VALUE result, lv;
+    int level = -1;
+    VALUE result;
 
-    rb_scan_args(argc, argv, "01", &lv);
-    if (!NIL_P(lv)) level = NUM2INT(lv);
-    if (level == 0) return ary_make_shared_copy(ary);
+    if (rb_check_arity(argc, 0, 1) && !NIL_P(argv[0])) {
+        level = NUM2INT(argv[0]);
+        if (level == 0) return ary_make_shared_copy(ary);
+    }
 
-    result = flatten(ary, level, &mod);
-    OBJ_INFECT(result, ary);
+    result = flatten(ary, level);
+    if (result == ary) {
+        result = ary_make_shared_copy(ary);
+    }
 
     return result;
 }
 
-#define OPTHASH_GIVEN_P(opts) \
-    (argc > 0 && !NIL_P((opts) = rb_check_hash_type(argv[argc-1])) && (--argc, 1))
-static ID id_random;
-
 #define RAND_UPTO(max) (long)rb_random_ulong_limited((randgen), (max)-1)
 
-/*
- *  call-seq:
- *     ary.shuffle!              -> ary
- *     ary.shuffle!(random: rng) -> ary
- *
- *  Shuffles elements in +self+ in place.
- *
- *     a = [ 1, 2, 3 ]           #=> [1, 2, 3]
- *     a.shuffle!                #=> [2, 3, 1]
- *     a                         #=> [2, 3, 1]
- *
- *  The optional +rng+ argument will be used as the random number generator.
- *
- *     a.shuffle!(random: Random.new(1))  #=> [1, 3, 2]
- */
-
 static VALUE
-rb_ary_shuffle_bang(int argc, VALUE *argv, VALUE ary)
+rb_ary_shuffle_bang(rb_execution_context_t *ec, VALUE ary, VALUE randgen)
 {
-    VALUE opts, randgen = rb_cRandom;
     long i, len;
 
-    if (OPTHASH_GIVEN_P(opts)) {
-	VALUE rnd;
-	ID keyword_ids[1];
-
-	keyword_ids[0] = id_random;
-	rb_get_kwargs(opts, keyword_ids, 0, 1, &rnd);
-	if (rnd != Qundef) {
-	    randgen = rnd;
-	}
-    }
-    rb_check_arity(argc, 0, 0);
     rb_ary_modify(ary);
     i = len = RARRAY_LEN(ary);
     RARRAY_PTR_USE(ary, ptr, {
-	while (i) {
-	    long j = RAND_UPTO(i);
-	    VALUE tmp;
-	    if (len != RARRAY_LEN(ary) || ptr != RARRAY_CONST_PTR(ary)) {
-		rb_raise(rb_eRuntimeError, "modified during shuffle");
-	    }
-	    tmp = ptr[--i];
-	    ptr[i] = ptr[j];
-	    ptr[j] = tmp;
-	}
+        while (i) {
+            long j = RAND_UPTO(i);
+            VALUE tmp;
+            if (len != RARRAY_LEN(ary) || ptr != RARRAY_CONST_PTR_TRANSIENT(ary)) {
+                rb_raise(rb_eRuntimeError, "modified during shuffle");
+            }
+            tmp = ptr[--i];
+            ptr[i] = ptr[j];
+            ptr[j] = tmp;
+        }
     }); /* WB: no new reference */
     return ary;
 }
 
-
-/*
- *  call-seq:
- *     ary.shuffle              -> new_ary
- *     ary.shuffle(random: rng) -> new_ary
- *
- *  Returns a new array with elements of +self+ shuffled.
- *
- *     a = [ 1, 2, 3 ]           #=> [1, 2, 3]
- *     a.shuffle                 #=> [2, 3, 1]
- *     a                         #=> [1, 2, 3]
- *
- *  The optional +rng+ argument will be used as the random number generator.
- *
- *     a.shuffle(random: Random.new(1))  #=> [1, 3, 2]
- */
-
 static VALUE
-rb_ary_shuffle(int argc, VALUE *argv, VALUE ary)
+rb_ary_shuffle(rb_execution_context_t *ec, VALUE ary, VALUE randgen)
 {
     ary = rb_ary_dup(ary);
-    rb_ary_shuffle_bang(argc, argv, ary);
+    rb_ary_shuffle_bang(ec, ary, randgen);
     return ary;
 }
 
-
-/*
- *  call-seq:
- *     ary.sample                  -> obj
- *     ary.sample(random: rng)     -> obj
- *     ary.sample(n)               -> new_ary
- *     ary.sample(n, random: rng)  -> new_ary
- *
- *  Choose a random element or +n+ random elements from the array.
- *
- *  The elements are chosen by using random and unique indices into the array
- *  in order to ensure that an element doesn't repeat itself unless the array
- *  already contained duplicate elements.
- *
- *  If the array is empty the first form returns +nil+ and the second form
- *  returns an empty array.
- *
- *  The optional +rng+ argument will be used as the random number generator.
- *
- *     a = [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 ]
- *     a.sample         #=> 7
- *     a.sample(4)      #=> [6, 4, 2, 5]
- */
-
-
 static VALUE
-rb_ary_sample(int argc, VALUE *argv, VALUE ary)
+ary_sample(rb_execution_context_t *ec, VALUE ary, VALUE randgen, VALUE nv, VALUE to_array)
 {
-    VALUE nv, result;
-    VALUE opts, randgen = rb_cRandom;
+    VALUE result;
     long n, len, i, j, k, idx[10];
     long rnds[numberof(idx)];
+    long memo_threshold;
 
-    if (OPTHASH_GIVEN_P(opts)) {
-	VALUE rnd;
-	ID keyword_ids[1];
-
-	keyword_ids[0] = id_random;
-	rb_get_kwargs(opts, keyword_ids, 0, 1, &rnd);
-	if (rnd != Qundef) {
-	    randgen = rnd;
-	}
-    }
     len = RARRAY_LEN(ary);
-    if (argc == 0) {
-	if (len < 2)
-	    i = 0;
-	else
-	    i = RAND_UPTO(len);
+    if (!to_array) {
+        if (len < 2)
+            i = 0;
+        else
+            i = RAND_UPTO(len);
 
-	return rb_ary_elt(ary, i);
+        return rb_ary_elt(ary, i);
     }
-    rb_scan_args(argc, argv, "1", &nv);
     n = NUM2LONG(nv);
     if (n < 0) rb_raise(rb_eArgError, "negative sample number");
     if (n > len) n = len;
     if (n <= numberof(idx)) {
-	for (i = 0; i < n; ++i) {
-	    rnds[i] = RAND_UPTO(len - i);
-	}
+        for (i = 0; i < n; ++i) {
+            rnds[i] = RAND_UPTO(len - i);
+        }
     }
     k = len;
     len = RARRAY_LEN(ary);
     if (len < k && n <= numberof(idx)) {
-	for (i = 0; i < n; ++i) {
-	    if (rnds[i] >= len) return rb_ary_new_capa(0);
-	}
+        for (i = 0; i < n; ++i) {
+            if (rnds[i] >= len) return rb_ary_new_capa(0);
+        }
     }
     if (n > len) n = len;
     switch (n) {
       case 0:
-	return rb_ary_new_capa(0);
+        return rb_ary_new_capa(0);
       case 1:
-	i = rnds[0];
-	return rb_ary_new_from_values(1, &RARRAY_AREF(ary, i));
+        i = rnds[0];
+        return rb_ary_new_from_args(1, RARRAY_AREF(ary, i));
       case 2:
-	i = rnds[0];
-	j = rnds[1];
-	if (j >= i) j++;
-	return rb_ary_new_from_args(2, RARRAY_AREF(ary, i), RARRAY_AREF(ary, j));
+        i = rnds[0];
+        j = rnds[1];
+        if (j >= i) j++;
+        return rb_ary_new_from_args(2, RARRAY_AREF(ary, i), RARRAY_AREF(ary, j));
       case 3:
-	i = rnds[0];
-	j = rnds[1];
-	k = rnds[2];
-	{
-	    long l = j, g = i;
-	    if (j >= i) l = i, g = ++j;
-	    if (k >= l && (++k >= g)) ++k;
-	}
-	return rb_ary_new_from_args(3, RARRAY_AREF(ary, i), RARRAY_AREF(ary, j), RARRAY_AREF(ary, k));
+        i = rnds[0];
+        j = rnds[1];
+        k = rnds[2];
+        {
+            long l = j, g = i;
+            if (j >= i) l = i, g = ++j;
+            if (k >= l && (++k >= g)) ++k;
+        }
+        return rb_ary_new_from_args(3, RARRAY_AREF(ary, i), RARRAY_AREF(ary, j), RARRAY_AREF(ary, k));
     }
+    memo_threshold =
+        len < 2560 ? len / 128 :
+        len < 5120 ? len / 64 :
+        len < 10240 ? len / 32 :
+        len / 16;
     if (n <= numberof(idx)) {
-	long sorted[numberof(idx)];
-	sorted[0] = idx[0] = rnds[0];
-	for (i=1; i<n; i++) {
-	    k = rnds[i];
-	    for (j = 0; j < i; ++j) {
-		if (k < sorted[j]) break;
-		++k;
-	    }
-	    memmove(&sorted[j+1], &sorted[j], sizeof(sorted[0])*(i-j));
-	    sorted[j] = idx[i] = k;
-	}
-	result = rb_ary_new_capa(n);
-	RARRAY_PTR_USE(result, ptr_result, {
-	    for (i=0; i<n; i++) {
-		ptr_result[i] = RARRAY_AREF(ary, idx[i]);
-	    }
-	});
+        long sorted[numberof(idx)];
+        sorted[0] = idx[0] = rnds[0];
+        for (i=1; i<n; i++) {
+            k = rnds[i];
+            for (j = 0; j < i; ++j) {
+                if (k < sorted[j]) break;
+                ++k;
+            }
+            memmove(&sorted[j+1], &sorted[j], sizeof(sorted[0])*(i-j));
+            sorted[j] = idx[i] = k;
+        }
+        result = rb_ary_new_capa(n);
+        RARRAY_PTR_USE_TRANSIENT(result, ptr_result, {
+            for (i=0; i<n; i++) {
+                ptr_result[i] = RARRAY_AREF(ary, idx[i]);
+            }
+        });
+    }
+    else if (n <= memo_threshold / 2) {
+        long max_idx = 0;
+#undef RUBY_UNTYPED_DATA_WARNING
+#define RUBY_UNTYPED_DATA_WARNING 0
+        VALUE vmemo = Data_Wrap_Struct(0, 0, st_free_table, 0);
+        st_table *memo = st_init_numtable_with_size(n);
+        DATA_PTR(vmemo) = memo;
+        result = rb_ary_new_capa(n);
+        RARRAY_PTR_USE(result, ptr_result, {
+            for (i=0; i<n; i++) {
+                long r = RAND_UPTO(len-i) + i;
+                ptr_result[i] = r;
+                if (r > max_idx) max_idx = r;
+            }
+            len = RARRAY_LEN(ary);
+            if (len <= max_idx) n = 0;
+            else if (n > len) n = len;
+            RARRAY_PTR_USE_TRANSIENT(ary, ptr_ary, {
+                for (i=0; i<n; i++) {
+                    long j2 = j = ptr_result[i];
+                    long i2 = i;
+                    st_data_t value;
+                    if (st_lookup(memo, (st_data_t)i, &value)) i2 = (long)value;
+                    if (st_lookup(memo, (st_data_t)j, &value)) j2 = (long)value;
+                    st_insert(memo, (st_data_t)j, (st_data_t)i2);
+                    ptr_result[i] = ptr_ary[j2];
+                }
+            });
+        });
+        DATA_PTR(vmemo) = 0;
+        st_free_table(memo);
     }
     else {
-	result = rb_ary_dup(ary);
-	RBASIC_CLEAR_CLASS(result);
-	RB_GC_GUARD(ary);
-	RARRAY_PTR_USE(result, ptr_result, {
-	    for (i=0; i<n; i++) {
-		j = RAND_UPTO(len-i) + i;
-		nv = ptr_result[j];
-		ptr_result[j] = ptr_result[i];
-		ptr_result[i] = nv;
-	    }
-	});
-	RBASIC_SET_CLASS_RAW(result, rb_cArray);
+        result = rb_ary_dup(ary);
+        RBASIC_CLEAR_CLASS(result);
+        RB_GC_GUARD(ary);
+        RARRAY_PTR_USE(result, ptr_result, {
+            for (i=0; i<n; i++) {
+                j = RAND_UPTO(len-i) + i;
+                nv = ptr_result[j];
+                ptr_result[j] = ptr_result[i];
+                ptr_result[i] = nv;
+            }
+        });
+        RBASIC_SET_CLASS_RAW(result, rb_cArray);
     }
     ARY_SET_LEN(result, n);
 
@@ -4855,55 +6878,73 @@ rb_ary_sample(int argc, VALUE *argv, VALUE ary)
 }
 
 static VALUE
+ary_sample0(rb_execution_context_t *ec, VALUE ary)
+{
+    return ary_sample(ec, ary, rb_cRandom, Qfalse, Qfalse);
+}
+
+static VALUE
 rb_ary_cycle_size(VALUE self, VALUE args, VALUE eobj)
 {
     long mul;
     VALUE n = Qnil;
     if (args && (RARRAY_LEN(args) > 0)) {
-	n = RARRAY_AREF(args, 0);
+        n = RARRAY_AREF(args, 0);
     }
     if (RARRAY_LEN(self) == 0) return INT2FIX(0);
-    if (n == Qnil) return DBL2NUM(INFINITY);
+    if (NIL_P(n)) return DBL2NUM(HUGE_VAL);
     mul = NUM2LONG(n);
     if (mul <= 0) return INT2FIX(0);
     n = LONG2FIX(mul);
-    return rb_funcallv(rb_ary_length(self), '*', 1, &n);
+    return rb_fix_mul_fix(rb_ary_length(self), n);
 }
 
 /*
  *  call-seq:
- *     ary.cycle(n=nil) { |obj| block }  -> nil
- *     ary.cycle(n=nil)                  -> Enumerator
+ *    array.cycle {|element| ... } -> nil
+ *    array.cycle(count) {|element| ... } -> nil
+ *    array.cycle -> new_enumerator
+ *    array.cycle(count) -> new_enumerator
  *
- *  Calls the given block for each element +n+ times or forever if +nil+ is
- *  given.
+ *  When called with positive \Integer argument +count+ and a block,
+ *  calls the block with each element, then does so again,
+ *  until it has done so +count+ times; returns +nil+:
  *
- *  Does nothing if a non-positive number is given or the array is empty.
+ *    output = []
+ *    [0, 1].cycle(2) {|element| output.push(element) } # => nil
+ *    output # => [0, 1, 0, 1]
  *
- *  Returns +nil+ if the loop has finished without getting interrupted.
+ *  If +count+ is zero or negative, does not call the block:
  *
- *  If no block is given, an Enumerator is returned instead.
+ *    [0, 1].cycle(0) {|element| fail 'Cannot happen' } # => nil
+ *    [0, 1].cycle(-1) {|element| fail 'Cannot happen' } # => nil
  *
- *     a = ["a", "b", "c"]
- *     a.cycle { |x| puts x }     # print, a, b, c, a, b, c,.. forever.
- *     a.cycle(2) { |x| puts x }  # print, a, b, c, a, b, c.
+ *  When a block is given, and argument is omitted or +nil+, cycles forever:
+ *
+ *    # Prints 0 and 1 forever.
+ *    [0, 1].cycle {|element| puts element }
+ *    [0, 1].cycle(nil) {|element| puts element }
+ *
+ *  When no block is given, returns a new \Enumerator:
+ *
+ *    [0, 1].cycle(2) # => #<Enumerator: [0, 1]:cycle(2)>
+ *    [0, 1].cycle # => # => #<Enumerator: [0, 1]:cycle>
+ *    [0, 1].cycle.first(5) # => [0, 1, 0, 1, 0]
  *
  */
-
 static VALUE
 rb_ary_cycle(int argc, VALUE *argv, VALUE ary)
 {
     long n, i;
-    VALUE nv = Qnil;
 
-    rb_scan_args(argc, argv, "01", &nv);
+    rb_check_arity(argc, 0, 1);
 
     RETURN_SIZED_ENUMERATOR(ary, argc, argv, rb_ary_cycle_size);
-    if (NIL_P(nv)) {
+    if (argc == 0 || NIL_P(argv[0])) {
         n = -1;
     }
     else {
-        n = NUM2LONG(nv);
+        n = NUM2LONG(argv[0]);
         if (n <= 0) return Qnil;
     }
 
@@ -4915,11 +6956,6 @@ rb_ary_cycle(int argc, VALUE *argv, VALUE ary)
     return Qnil;
 }
 
-#define tmpbuf(n, size) rb_str_tmp_new((n)*(size))
-#define tmpbuf_discard(s) (rb_str_resize((s), 0L), RBASIC_SET_CLASS_RAW(s, rb_cString))
-#define tmpary(n) rb_ary_tmp_new(n)
-#define tmpary_discard(a) (ary_discard(a), RBASIC_SET_CLASS_RAW(a, rb_cArray))
-
 /*
  * Build a ruby array of the corresponding values and yield it to the
  * associated block.
@@ -4929,11 +6965,9 @@ static int
 yield_indexed_values(const VALUE values, const long r, const long *const p)
 {
     const VALUE result = rb_ary_new2(r);
-    VALUE *const result_array = RARRAY_PTR(result);
-    const VALUE *const values_array = RARRAY_CONST_PTR(values);
     long i;
 
-    for (i = 0; i < r; i++) result_array[i] = values_array[p[i]];
+    for (i = 0; i < r; i++) ARY_SET(result, i, RARRAY_AREF(values, p[i]));
     ARY_SET_LEN(result, r);
     rb_yield(result);
     return !RBASIC(values)->klass;
@@ -4957,46 +6991,52 @@ permute0(const long n, const long r, long *const p, char *const used, const VALU
     long i = 0, index = 0;
 
     for (;;) {
-	const char *const unused = memchr(&used[i], 0, n-i);
-	if (!unused) {
-	    if (!index) break;
-	    i = p[--index];                /* pop index */
-	    used[i++] = 0;                 /* index unused */
-	}
-	else {
-	    i = unused - used;
-	    p[index] = i;
-	    used[i] = 1;                   /* mark index used */
-	    ++index;
-	    if (index < r-1) {             /* if not done yet */
-		p[index] = i = 0;
-		continue;
-	    }
-	    for (i = 0; i < n; ++i) {
-		if (used[i]) continue;
-		p[index] = i;
-		if (!yield_indexed_values(values, r, p)) {
-		    rb_raise(rb_eRuntimeError, "permute reentered");
-		}
-	    }
-	    i = p[--index];                /* pop index */
-	    used[i] = 0;                   /* index unused */
-	    p[index] = ++i;
-	}
+        const char *const unused = memchr(&used[i], 0, n-i);
+        if (!unused) {
+            if (!index) break;
+            i = p[--index];                /* pop index */
+            used[i++] = 0;                 /* index unused */
+        }
+        else {
+            i = unused - used;
+            p[index] = i;
+            used[i] = 1;                   /* mark index used */
+            ++index;
+            if (index < r-1) {             /* if not done yet */
+                p[index] = i = 0;
+                continue;
+            }
+            for (i = 0; i < n; ++i) {
+                if (used[i]) continue;
+                p[index] = i;
+                if (!yield_indexed_values(values, r, p)) {
+                    rb_raise(rb_eRuntimeError, "permute reentered");
+                }
+            }
+            i = p[--index];                /* pop index */
+            used[i] = 0;                   /* index unused */
+            p[index] = ++i;
+        }
     }
 }
 
 /*
  * Returns the product of from, from-1, ..., from - how_many + 1.
- * http://en.wikipedia.org/wiki/Pochhammer_symbol
+ * https://en.wikipedia.org/wiki/Pochhammer_symbol
  */
 static VALUE
 descending_factorial(long from, long how_many)
 {
-    VALUE cnt = LONG2FIX(how_many >= 0);
-    while (how_many-- > 0) {
-	VALUE v = LONG2FIX(from--);
-	cnt = rb_funcallv(cnt, '*', 1, &v);
+    VALUE cnt;
+    if (how_many > 0) {
+        cnt = LONG2FIX(from);
+        while (--how_many > 0) {
+            long v = --from;
+            cnt = rb_int_mul(cnt, LONG2FIX(v));
+        }
+    }
+    else {
+        cnt = LONG2FIX(how_many == 0);
     }
     return cnt;
 }
@@ -5004,16 +7044,23 @@ descending_factorial(long from, long how_many)
 static VALUE
 binomial_coefficient(long comb, long size)
 {
-    VALUE r, v;
+    VALUE r;
+    long i;
     if (comb > size-comb) {
-	comb = size-comb;
+        comb = size-comb;
     }
     if (comb < 0) {
-	return LONG2FIX(0);
+        return LONG2FIX(0);
+    }
+    else if (comb == 0) {
+        return LONG2FIX(1);
     }
-    r = descending_factorial(size, comb);
-    v = descending_factorial(comb, comb);
-    return rb_funcallv(r, id_div, 1, &v);
+    r = LONG2FIX(size);
+    for (i = 1; i < comb; ++i) {
+        r = rb_int_mul(r, LONG2FIX(size - i));
+        r = rb_int_idiv(r, LONG2FIX(i + 1));
+    }
+    return r;
 }
 
 static VALUE
@@ -5027,66 +7074,118 @@ rb_ary_permutation_size(VALUE ary, VALUE args, VALUE eobj)
 
 /*
  *  call-seq:
- *     ary.permutation { |p| block }          -> ary
- *     ary.permutation                        -> Enumerator
- *     ary.permutation(n) { |p| block }       -> ary
- *     ary.permutation(n)                     -> Enumerator
+ *    array.permutation {|element| ... } -> self
+ *    array.permutation(n) {|element| ... } -> self
+ *    array.permutation -> new_enumerator
+ *    array.permutation(n) -> new_enumerator
+ *
+ *  When invoked with a block, yield all permutations of elements of +self+; returns +self+.
+ *  The order of permutations is indeterminate.
+ *
+ *  When a block and an in-range positive \Integer argument +n+ (<tt>0 < n <= self.size</tt>)
+ *  are given, calls the block with all +n+-tuple permutations of +self+.
+ *
+ *  Example:
+ *
+ *    a = [0, 1, 2]
+ *    a.permutation(2) {|permutation| p permutation }
+ *
+ *  Output:
+ *
+ *    [0, 1]
+ *    [0, 2]
+ *    [1, 0]
+ *    [1, 2]
+ *    [2, 0]
+ *    [2, 1]
+ *
+ *  Another example:
+ *
+ *    a = [0, 1, 2]
+ *    a.permutation(3) {|permutation| p permutation }
+ *
+ *  Output:
+ *
+ *    [0, 1, 2]
+ *    [0, 2, 1]
+ *    [1, 0, 2]
+ *    [1, 2, 0]
+ *    [2, 0, 1]
+ *    [2, 1, 0]
+ *
+ *  When +n+ is zero, calls the block once with a new empty \Array:
+ *
+ *    a = [0, 1, 2]
+ *    a.permutation(0) {|permutation| p permutation }
+ *
+ *  Output:
+ *
+ *    []
+ *
+ *  When +n+ is out of range (negative or larger than <tt>self.size</tt>),
+ *  does not call the block:
  *
- * When invoked with a block, yield all permutations of length +n+ of the
- * elements of the array, then return the array itself.
+ *    a = [0, 1, 2]
+ *    a.permutation(-1) {|permutation| fail 'Cannot happen' }
+ *    a.permutation(4) {|permutation| fail 'Cannot happen' }
  *
- * If +n+ is not specified, yield all permutations of all elements.
+ *  When a block given but no argument,
+ *  behaves the same as <tt>a.permutation(a.size)</tt>:
  *
- * The implementation makes no guarantees about the order in which the
- * permutations are yielded.
+ *    a = [0, 1, 2]
+ *    a.permutation {|permutation| p permutation }
  *
- * If no block is given, an Enumerator is returned instead.
+ *  Output:
  *
- * Examples:
+ *    [0, 1, 2]
+ *    [0, 2, 1]
+ *    [1, 0, 2]
+ *    [1, 2, 0]
+ *    [2, 0, 1]
+ *    [2, 1, 0]
+ *
+ *  Returns a new \Enumerator if no block given:
+ *
+ *    a = [0, 1, 2]
+ *    a.permutation # => #<Enumerator: [0, 1, 2]:permutation>
+ *    a.permutation(2) # => #<Enumerator: [0, 1, 2]:permutation(2)>
  *
- *   a = [1, 2, 3]
- *   a.permutation.to_a    #=> [[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]]
- *   a.permutation(1).to_a #=> [[1],[2],[3]]
- *   a.permutation(2).to_a #=> [[1,2],[1,3],[2,1],[2,3],[3,1],[3,2]]
- *   a.permutation(3).to_a #=> [[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]]
- *   a.permutation(0).to_a #=> [[]] # one permutation of length 0
- *   a.permutation(4).to_a #=> []   # no permutations of length 4
  */
 
 static VALUE
 rb_ary_permutation(int argc, VALUE *argv, VALUE ary)
 {
-    VALUE num;
     long r, n, i;
 
     n = RARRAY_LEN(ary);                  /* Array length */
     RETURN_SIZED_ENUMERATOR(ary, argc, argv, rb_ary_permutation_size);   /* Return enumerator if no block */
-    rb_scan_args(argc, argv, "01", &num);
-    r = NIL_P(num) ? n : NUM2LONG(num);   /* Permutation size from argument */
+    r = n;
+    if (rb_check_arity(argc, 0, 1) && !NIL_P(argv[0]))
+        r = NUM2LONG(argv[0]);            /* Permutation size from argument */
 
     if (r < 0 || n < r) {
-	/* no permutations: yield nothing */
+        /* no permutations: yield nothing */
     }
     else if (r == 0) { /* exactly one permutation: the zero-length array */
-	rb_yield(rb_ary_new2(0));
+        rb_yield(rb_ary_new2(0));
     }
     else if (r == 1) { /* this is a special, easy case */
-	for (i = 0; i < RARRAY_LEN(ary); i++) {
-	    rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
-	}
+        for (i = 0; i < RARRAY_LEN(ary); i++) {
+            rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
+        }
     }
     else {             /* this is the general case */
-	volatile VALUE t0;
-	long *p = ALLOCV_N(long, t0, r+roomof(n, sizeof(long)));
-	char *used = (char*)(p + r);
-	VALUE ary0 = ary_make_shared_copy(ary); /* private defensive copy of ary */
-	RBASIC_CLEAR_CLASS(ary0);
+        volatile VALUE t0;
+        long *p = ALLOCV_N(long, t0, r+roomof(n, sizeof(long)));
+        char *used = (char*)(p + r);
+        VALUE ary0 = ary_make_shared_copy(ary); /* private defensive copy of ary */
+        RBASIC_CLEAR_CLASS(ary0);
 
-	MEMZERO(used, char, n); /* initialize array */
+        MEMZERO(used, char, n); /* initialize array */
 
-	permute0(n, r, p, used, ary0); /* compute and yield permutations */
-	ALLOCV_END(t0);
-	RBASIC_SET_CLASS_RAW(ary0, rb_cArray);
+        permute0(n, r, p, used, ary0); /* compute and yield permutations */
+        ALLOCV_END(t0);
+        RBASIC_SET_CLASS_RAW(ary0, rb_cArray);
     }
     return ary;
 }
@@ -5099,16 +7198,16 @@ combinate0(const long len, const long n, long *const stack, const VALUE values)
     MEMZERO(stack+1, long, n);
     stack[0] = -1;
     for (;;) {
-	for (lev++; lev < n; lev++) {
-	    stack[lev+1] = stack[lev]+1;
-	}
-	if (!yield_indexed_values(values, n, stack+1)) {
-	    rb_raise(rb_eRuntimeError, "combination reentered");
-	}
-	do {
-	    if (lev == 0) return;
-	    stack[lev--]++;
-	} while (stack[lev+1]+n == len+lev+1);
+        for (lev++; lev < n; lev++) {
+            stack[lev+1] = stack[lev]+1;
+        }
+        if (!yield_indexed_values(values, n, stack+1)) {
+            rb_raise(rb_eRuntimeError, "combination reentered");
+        }
+        do {
+            if (lev == 0) return;
+            stack[lev--]++;
+        } while (stack[lev+1]+n == len+lev+1);
     }
 }
 
@@ -5123,26 +7222,55 @@ rb_ary_combination_size(VALUE ary, VALUE args, VALUE eobj)
 
 /*
  *  call-seq:
- *     ary.combination(n) { |c| block }    -> ary
- *     ary.combination(n)                  -> Enumerator
+ *    array.combination(n) {|element| ... } -> self
+ *    array.combination(n) -> new_enumerator
+ *
+ *  Calls the block, if given, with combinations of elements of +self+;
+ *  returns +self+. The order of combinations is indeterminate.
+ *
+ *  When a block and an in-range positive \Integer argument +n+ (<tt>0 < n <= self.size</tt>)
+ *  are given, calls the block with all +n+-tuple combinations of +self+.
+ *
+ *  Example:
+ *
+ *    a = [0, 1, 2]
+ *    a.combination(2) {|combination| p combination }
+ *
+ *  Output:
+ *
+ *    [0, 1]
+ *    [0, 2]
+ *    [1, 2]
+ *
+ *  Another example:
+ *
+ *    a = [0, 1, 2]
+ *    a.combination(3) {|combination| p combination }
  *
- * When invoked with a block, yields all combinations of length +n+ of elements
- * from the array and then returns the array itself.
+ *  Output:
  *
- * The implementation makes no guarantees about the order in which the
- * combinations are yielded.
+ *    [0, 1, 2]
  *
- * If no block is given, an Enumerator is returned instead.
+ *  When +n+ is zero, calls the block once with a new empty \Array:
  *
- * Examples:
+ *    a = [0, 1, 2]
+ *    a1 = a.combination(0) {|combination| p combination }
  *
- *     a = [1, 2, 3, 4]
- *     a.combination(1).to_a  #=> [[1],[2],[3],[4]]
- *     a.combination(2).to_a  #=> [[1,2],[1,3],[1,4],[2,3],[2,4],[3,4]]
- *     a.combination(3).to_a  #=> [[1,2,3],[1,2,4],[1,3,4],[2,3,4]]
- *     a.combination(4).to_a  #=> [[1,2,3,4]]
- *     a.combination(0).to_a  #=> [[]] # one combination of length 0
- *     a.combination(5).to_a  #=> []   # no combinations of length 5
+ *  Output:
+ *
+ *    []
+ *
+ *  When +n+ is out of range (negative or larger than <tt>self.size</tt>),
+ *  does not call the block:
+ *
+ *    a = [0, 1, 2]
+ *    a.combination(-1) {|combination| fail 'Cannot happen' }
+ *    a.combination(4) {|combination| fail 'Cannot happen' }
+ *
+ *  Returns a new \Enumerator if no block given:
+ *
+ *    a = [0, 1, 2]
+ *    a.combination(2) # => #<Enumerator: [0, 1, 2]:combination(2)>
  *
  */
 
@@ -5155,25 +7283,25 @@ rb_ary_combination(VALUE ary, VALUE num)
     RETURN_SIZED_ENUMERATOR(ary, 1, &num, rb_ary_combination_size);
     len = RARRAY_LEN(ary);
     if (n < 0 || len < n) {
-	/* yield nothing */
+        /* yield nothing */
     }
     else if (n == 0) {
-	rb_yield(rb_ary_new2(0));
+        rb_yield(rb_ary_new2(0));
     }
     else if (n == 1) {
-	for (i = 0; i < len; i++) {
-	    rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
-	}
+        for (i = 0; i < RARRAY_LEN(ary); i++) {
+            rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
+        }
     }
     else {
-	VALUE ary0 = ary_make_shared_copy(ary); /* private defensive copy of ary */
-	volatile VALUE t0;
-	long *stack = ALLOCV_N(long, t0, n+1);
+        VALUE ary0 = ary_make_shared_copy(ary); /* private defensive copy of ary */
+        volatile VALUE t0;
+        long *stack = ALLOCV_N(long, t0, n+1);
 
-	RBASIC_CLEAR_CLASS(ary0);
-	combinate0(len, n, stack, ary0);
-	ALLOCV_END(t0);
-	RBASIC_SET_CLASS_RAW(ary0, rb_cArray);
+        RBASIC_CLEAR_CLASS(ary0);
+        combinate0(len, n, stack, ary0);
+        ALLOCV_END(t0);
+        RBASIC_SET_CLASS_RAW(ary0, rb_cArray);
     }
     return ary;
 }
@@ -5197,19 +7325,19 @@ rpermute0(const long n, const long r, long *const p, const VALUE values)
 
     p[index] = i;
     for (;;) {
-	if (++index < r-1) {
-	    p[index] = i = 0;
-	    continue;
-	}
-	for (i = 0; i < n; ++i) {
-	    p[index] = i;
-	    if (!yield_indexed_values(values, r, p)) {
-		rb_raise(rb_eRuntimeError, "repeated permute reentered");
-	    }
-	}
-	do {
-	    if (index <= 0) return;
-	} while ((i = ++p[--index]) >= n);
+        if (++index < r-1) {
+            p[index] = i = 0;
+            continue;
+        }
+        for (i = 0; i < n; ++i) {
+            p[index] = i;
+            if (!yield_indexed_values(values, r, p)) {
+                rb_raise(rb_eRuntimeError, "repeated permute reentered");
+            }
+        }
+        do {
+            if (index <= 0) return;
+        } while ((i = ++p[--index]) >= n);
     }
 }
 
@@ -5218,39 +7346,81 @@ rb_ary_repeated_permutation_size(VALUE ary, VALUE args, VALUE eobj)
 {
     long n = RARRAY_LEN(ary);
     long k = NUM2LONG(RARRAY_AREF(args, 0));
-    VALUE v;
 
     if (k < 0) {
-	return LONG2FIX(0);
+        return LONG2FIX(0);
     }
-
-    v = LONG2NUM(k);
-    return rb_funcallv(LONG2NUM(n), id_power, 1, &v);
+    if (n <= 0) {
+        return LONG2FIX(!k);
+    }
+    return rb_int_positive_pow(n, (unsigned long)k);
 }
 
 /*
  *  call-seq:
- *     ary.repeated_permutation(n) { |p| block } -> ary
- *     ary.repeated_permutation(n)               -> Enumerator
+ *    array.repeated_permutation(n) {|permutation| ... } -> self
+ *    array.repeated_permutation(n) -> new_enumerator
+ *
+ *  Calls the block with each repeated permutation of length +n+ of the elements of +self+;
+ *  each permutation is an \Array;
+ *  returns +self+. The order of the permutations is indeterminate.
  *
- * When invoked with a block, yield all repeated permutations of length +n+ of
- * the elements of the array, then return the array itself.
+ *  When a block and a positive \Integer argument +n+ are given, calls the block with each
+ *  +n+-tuple repeated permutation of the elements of +self+.
+ *  The number of permutations is <tt>self.size**n</tt>.
  *
- * The implementation makes no guarantees about the order in which the repeated
- * permutations are yielded.
+ *  +n+ = 1:
  *
- * If no block is given, an Enumerator is returned instead.
+ *    a = [0, 1, 2]
+ *    a.repeated_permutation(1) {|permutation| p permutation }
  *
- * Examples:
+ *  Output:
+ *
+ *    [0]
+ *    [1]
+ *    [2]
+ *
+ *  +n+ = 2:
+ *
+ *    a.repeated_permutation(2) {|permutation| p permutation }
+ *
+ *  Output:
+ *
+ *    [0, 0]
+ *    [0, 1]
+ *    [0, 2]
+ *    [1, 0]
+ *    [1, 1]
+ *    [1, 2]
+ *    [2, 0]
+ *    [2, 1]
+ *    [2, 2]
+ *
+ *  If +n+ is zero, calls the block once with an empty \Array.
+ *
+ *  If +n+ is negative, does not call the block:
+ *
+ *    a.repeated_permutation(-1) {|permutation| fail 'Cannot happen' }
+ *
+ *  Returns a new \Enumerator if no block given:
+ *
+ *    a = [0, 1, 2]
+ *    a.repeated_permutation(2) # => #<Enumerator: [0, 1, 2]:permutation(2)>
+ *
+ *  Using Enumerators, it's convenient to show the permutations and counts
+ *  for some values of +n+:
+ *
+ *    e = a.repeated_permutation(0)
+ *    e.size # => 1
+ *    e.to_a # => [[]]
+ *    e = a.repeated_permutation(1)
+ *    e.size # => 3
+ *    e.to_a # => [[0], [1], [2]]
+ *    e = a.repeated_permutation(2)
+ *    e.size # => 9
+ *    e.to_a # => [[0, 0], [0, 1], [0, 2], [1, 0], [1, 1], [1, 2], [2, 0], [2, 1], [2, 2]]
  *
- *     a = [1, 2]
- *     a.repeated_permutation(1).to_a  #=> [[1], [2]]
- *     a.repeated_permutation(2).to_a  #=> [[1,1],[1,2],[2,1],[2,2]]
- *     a.repeated_permutation(3).to_a  #=> [[1,1,1],[1,1,2],[1,2,1],[1,2,2],
- *                                     #    [2,1,1],[2,1,2],[2,2,1],[2,2,2]]
- *     a.repeated_permutation(0).to_a  #=> [[]] # one permutation of length 0
  */
-
 static VALUE
 rb_ary_repeated_permutation(VALUE ary, VALUE num)
 {
@@ -5261,25 +7431,25 @@ rb_ary_repeated_permutation(VALUE ary, VALUE num)
     r = NUM2LONG(num);                    /* Permutation size from argument */
 
     if (r < 0) {
-	/* no permutations: yield nothing */
+        /* no permutations: yield nothing */
     }
     else if (r == 0) { /* exactly one permutation: the zero-length array */
-	rb_yield(rb_ary_new2(0));
+        rb_yield(rb_ary_new2(0));
     }
     else if (r == 1) { /* this is a special, easy case */
-	for (i = 0; i < RARRAY_LEN(ary); i++) {
-	    rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
-	}
+        for (i = 0; i < RARRAY_LEN(ary); i++) {
+            rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
+        }
     }
     else {             /* this is the general case */
-	volatile VALUE t0;
-	long *p = ALLOCV_N(long, t0, r);
-	VALUE ary0 = ary_make_shared_copy(ary); /* private defensive copy of ary */
-	RBASIC_CLEAR_CLASS(ary0);
+        volatile VALUE t0;
+        long *p = ALLOCV_N(long, t0, r);
+        VALUE ary0 = ary_make_shared_copy(ary); /* private defensive copy of ary */
+        RBASIC_CLEAR_CLASS(ary0);
 
-	rpermute0(n, r, p, ary0); /* compute and yield repeated permutations */
-	ALLOCV_END(t0);
-	RBASIC_SET_CLASS_RAW(ary0, rb_cArray);
+        rpermute0(n, r, p, ary0); /* compute and yield repeated permutations */
+        ALLOCV_END(t0);
+        RBASIC_SET_CLASS_RAW(ary0, rb_cArray);
     }
     return ary;
 }
@@ -5291,19 +7461,19 @@ rcombinate0(const long n, const long r, long *const p, const long rest, const VA
 
     p[index] = i;
     for (;;) {
-	if (++index < r-1) {
-	    p[index] = i;
-	    continue;
-	}
-	for (; i < n; ++i) {
-	    p[index] = i;
-	    if (!yield_indexed_values(values, r, p)) {
-		rb_raise(rb_eRuntimeError, "repeated combination reentered");
-	    }
-	}
-	do {
-	    if (index <= 0) return;
-	} while ((i = ++p[--index]) >= n);
+        if (++index < r-1) {
+            p[index] = i;
+            continue;
+        }
+        for (; i < n; ++i) {
+            p[index] = i;
+            if (!yield_indexed_values(values, r, p)) {
+                rb_raise(rb_eRuntimeError, "repeated combination reentered");
+            }
+        }
+        do {
+            if (index <= 0) return;
+        } while ((i = ++p[--index]) >= n);
     }
 }
 
@@ -5313,35 +7483,71 @@ rb_ary_repeated_combination_size(VALUE ary, VALUE args, VALUE eobj)
     long n = RARRAY_LEN(ary);
     long k = NUM2LONG(RARRAY_AREF(args, 0));
     if (k == 0) {
-	return LONG2FIX(1);
+        return LONG2FIX(1);
     }
     return binomial_coefficient(k, n + k - 1);
 }
 
 /*
  *  call-seq:
- *     ary.repeated_combination(n) { |c| block } -> ary
- *     ary.repeated_combination(n)               -> Enumerator
+ *    array.repeated_combination(n) {|combination| ... } -> self
+ *    array.repeated_combination(n) -> new_enumerator
+ *
+ *  Calls the block with each repeated combination of length +n+ of the elements of +self+;
+ *  each combination is an \Array;
+ *  returns +self+. The order of the combinations is indeterminate.
+ *
+ *  When a block and a positive \Integer argument +n+ are given, calls the block with each
+ *  +n+-tuple repeated combination of the elements of +self+.
+ *  The number of combinations is <tt>(n+1)(n+2)/2</tt>.
+ *
+ *  +n+ = 1:
+ *
+ *    a = [0, 1, 2]
+ *    a.repeated_combination(1) {|combination| p combination }
+ *
+ *  Output:
+ *
+ *    [0]
+ *    [1]
+ *    [2]
+ *
+ *  +n+ = 2:
+ *
+ *    a.repeated_combination(2) {|combination| p combination }
+ *
+ *  Output:
+ *
+ *    [0, 0]
+ *    [0, 1]
+ *    [0, 2]
+ *    [1, 1]
+ *    [1, 2]
+ *    [2, 2]
  *
- * When invoked with a block, yields all repeated combinations of length +n+ of
- * elements from the array and then returns the array itself.
+ *  If +n+ is zero, calls the block once with an empty \Array.
  *
- * The implementation makes no guarantees about the order in which the repeated
- * combinations are yielded.
+ *  If +n+ is negative, does not call the block:
  *
- * If no block is given, an Enumerator is returned instead.
+ *    a.repeated_combination(-1) {|combination| fail 'Cannot happen' }
  *
- * Examples:
+ *  Returns a new \Enumerator if no block given:
  *
- *   a = [1, 2, 3]
- *   a.repeated_combination(1).to_a  #=> [[1], [2], [3]]
- *   a.repeated_combination(2).to_a  #=> [[1,1],[1,2],[1,3],[2,2],[2,3],[3,3]]
- *   a.repeated_combination(3).to_a  #=> [[1,1,1],[1,1,2],[1,1,3],[1,2,2],[1,2,3],
- *                                   #    [1,3,3],[2,2,2],[2,2,3],[2,3,3],[3,3,3]]
- *   a.repeated_combination(4).to_a  #=> [[1,1,1,1],[1,1,1,2],[1,1,1,3],[1,1,2,2],[1,1,2,3],
- *                                   #    [1,1,3,3],[1,2,2,2],[1,2,2,3],[1,2,3,3],[1,3,3,3],
- *                                   #    [2,2,2,2],[2,2,2,3],[2,2,3,3],[2,3,3,3],[3,3,3,3]]
- *   a.repeated_combination(0).to_a  #=> [[]] # one combination of length 0
+ *    a = [0, 1, 2]
+ *    a.repeated_combination(2) # => #<Enumerator: [0, 1, 2]:combination(2)>
+ *
+ *  Using Enumerators, it's convenient to show the combinations and counts
+ *  for some values of +n+:
+ *
+ *    e = a.repeated_combination(0)
+ *    e.size # => 1
+ *    e.to_a # => [[]]
+ *    e = a.repeated_combination(1)
+ *    e.size # => 3
+ *    e.to_a # => [[0], [1], [2]]
+ *    e = a.repeated_combination(2)
+ *    e.size # => 6
+ *    e.to_a # => [[0, 0], [0, 1], [0, 2], [1, 1], [1, 2], [2, 2]]
  *
  */
 
@@ -5354,67 +7560,105 @@ rb_ary_repeated_combination(VALUE ary, VALUE num)
     RETURN_SIZED_ENUMERATOR(ary, 1, &num, rb_ary_repeated_combination_size);   /* Return enumerator if no block */
     len = RARRAY_LEN(ary);
     if (n < 0) {
-	/* yield nothing */
+        /* yield nothing */
     }
     else if (n == 0) {
-	rb_yield(rb_ary_new2(0));
+        rb_yield(rb_ary_new2(0));
     }
     else if (n == 1) {
-	for (i = 0; i < len; i++) {
-	    rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
-	}
+        for (i = 0; i < RARRAY_LEN(ary); i++) {
+            rb_yield(rb_ary_new3(1, RARRAY_AREF(ary, i)));
+        }
     }
     else if (len == 0) {
-	/* yield nothing */
+        /* yield nothing */
     }
     else {
-	volatile VALUE t0;
-	long *p = ALLOCV_N(long, t0, n);
-	VALUE ary0 = ary_make_shared_copy(ary); /* private defensive copy of ary */
-	RBASIC_CLEAR_CLASS(ary0);
+        volatile VALUE t0;
+        long *p = ALLOCV_N(long, t0, n);
+        VALUE ary0 = ary_make_shared_copy(ary); /* private defensive copy of ary */
+        RBASIC_CLEAR_CLASS(ary0);
 
-	rcombinate0(len, n, p, n, ary0); /* compute and yield repeated combinations */
-	ALLOCV_END(t0);
-	RBASIC_SET_CLASS_RAW(ary0, rb_cArray);
+        rcombinate0(len, n, p, n, ary0); /* compute and yield repeated combinations */
+        ALLOCV_END(t0);
+        RBASIC_SET_CLASS_RAW(ary0, rb_cArray);
     }
     return ary;
 }
 
 /*
  *  call-seq:
- *     ary.product(other_ary, ...)                -> new_ary
- *     ary.product(other_ary, ...) { |p| block }  -> ary
+ *    array.product(*other_arrays) -> new_array
+ *    array.product(*other_arrays) {|combination| ... } -> self
+ *
+ *  Computes and returns or yields all combinations of elements from all the Arrays,
+ *  including both +self+ and +other_arrays+:
+ *
+ *  - The number of combinations is the product of the sizes of all the arrays,
+ *    including both +self+ and +other_arrays+.
+ *  - The order of the returned combinations is indeterminate.
+ *
+ *  When no block is given, returns the combinations as an \Array of Arrays:
+ *
+ *    a = [0, 1, 2]
+ *    a1 = [3, 4]
+ *    a2 = [5, 6]
+ *    p = a.product(a1)
+ *    p.size # => 6 # a.size * a1.size
+ *    p # => [[0, 3], [0, 4], [1, 3], [1, 4], [2, 3], [2, 4]]
+ *    p = a.product(a1, a2)
+ *    p.size # => 12 # a.size * a1.size * a2.size
+ *    p # => [[0, 3, 5], [0, 3, 6], [0, 4, 5], [0, 4, 6], [1, 3, 5], [1, 3, 6], [1, 4, 5], [1, 4, 6], [2, 3, 5], [2, 3, 6], [2, 4, 5], [2, 4, 6]]
+ *
+ *  If any argument is an empty \Array, returns an empty \Array.
+ *
+ *  If no argument is given, returns an \Array of 1-element Arrays,
+ *  each containing an element of +self+:
+ *
+ *    a.product # => [[0], [1], [2]]
+ *
+ *  When a block is given, yields each combination as an \Array; returns +self+:
+ *
+ *    a.product(a1) {|combination| p combination }
+ *
+ *  Output:
+ *
+ *    [0, 3]
+ *    [0, 4]
+ *    [1, 3]
+ *    [1, 4]
+ *    [2, 3]
+ *    [2, 4]
  *
- *  Returns an array of all combinations of elements from all arrays.
+ *  If any argument is an empty \Array, does not call the block:
  *
- *  The length of the returned array is the product of the length of +self+ and
- *  the argument arrays.
+ *    a.product(a1, a2, []) {|combination| fail 'Cannot happen' }
  *
- *  If given a block, #product will yield all combinations and return +self+
- *  instead.
+ *  If no argument is given, yields each element of +self+ as a 1-element \Array:
+ *
+ *    a.product {|combination| p combination }
+ *
+ *  Output:
+ *
+ *    [0]
+ *    [1]
+ *    [2]
  *
- *     [1,2,3].product([4,5])     #=> [[1,4],[1,5],[2,4],[2,5],[3,4],[3,5]]
- *     [1,2].product([1,2])       #=> [[1,1],[1,2],[2,1],[2,2]]
- *     [1,2].product([3,4],[5,6]) #=> [[1,3,5],[1,3,6],[1,4,5],[1,4,6],
- *                                #     [2,3,5],[2,3,6],[2,4,5],[2,4,6]]
- *     [1,2].product()            #=> [[1],[2]]
- *     [1,2].product([])          #=> []
  */
 
 static VALUE
 rb_ary_product(int argc, VALUE *argv, VALUE ary)
 {
     int n = argc+1;    /* How many arrays we're operating on */
-    volatile VALUE t0 = tmpary(n);
-    volatile VALUE t1 = tmpbuf(n, sizeof(int));
+    volatile VALUE t0 = rb_ary_hidden_new(n);
+    volatile VALUE t1 = Qundef;
     VALUE *arrays = RARRAY_PTR(t0); /* The arrays we're computing the product of */
-    int *counters = (int*)RSTRING_PTR(t1); /* The current position in each one */
+    int *counters = ALLOCV_N(int, t1, n); /* The current position in each one */
     VALUE result = Qnil;      /* The array we'll be returning, when no block given */
     long i,j;
     long resultlen = 1;
 
     RBASIC_CLEAR_CLASS(t0);
-    RBASIC_CLEAR_CLASS(t1);
 
     /* initialize the arrays of arrays */
     ARY_SET_LEN(t0, n);
@@ -5427,81 +7671,84 @@ rb_ary_product(int argc, VALUE *argv, VALUE ary)
 
     /* Otherwise, allocate and fill in an array of results */
     if (rb_block_given_p()) {
-	/* Make defensive copies of arrays; exit if any is empty */
-	for (i = 0; i < n; i++) {
-	    if (RARRAY_LEN(arrays[i]) == 0) goto done;
-	    arrays[i] = ary_make_shared_copy(arrays[i]);
-	}
+        /* Make defensive copies of arrays; exit if any is empty */
+        for (i = 0; i < n; i++) {
+            if (RARRAY_LEN(arrays[i]) == 0) goto done;
+            arrays[i] = ary_make_shared_copy(arrays[i]);
+        }
     }
     else {
-	/* Compute the length of the result array; return [] if any is empty */
-	for (i = 0; i < n; i++) {
-	    long k = RARRAY_LEN(arrays[i]);
-	    if (k == 0) {
-		result = rb_ary_new2(0);
-		goto done;
-	    }
+        /* Compute the length of the result array; return [] if any is empty */
+        for (i = 0; i < n; i++) {
+            long k = RARRAY_LEN(arrays[i]);
+            if (k == 0) {
+                result = rb_ary_new2(0);
+                goto done;
+            }
             if (MUL_OVERFLOW_LONG_P(resultlen, k))
-		rb_raise(rb_eRangeError, "too big to product");
-	    resultlen *= k;
-	}
-	result = rb_ary_new2(resultlen);
+                rb_raise(rb_eRangeError, "too big to product");
+            resultlen *= k;
+        }
+        result = rb_ary_new2(resultlen);
     }
     for (;;) {
-	int m;
-	/* fill in one subarray */
-	VALUE subarray = rb_ary_new2(n);
-	for (j = 0; j < n; j++) {
-	    rb_ary_push(subarray, rb_ary_entry(arrays[j], counters[j]));
-	}
-
-	/* put it on the result array */
-	if (NIL_P(result)) {
-	    FL_SET(t0, FL_USER5);
-	    rb_yield(subarray);
-	    if (! FL_TEST(t0, FL_USER5)) {
-		rb_raise(rb_eRuntimeError, "product reentered");
-	    }
-	    else {
-		FL_UNSET(t0, FL_USER5);
-	    }
-	}
-	else {
-	    rb_ary_push(result, subarray);
-	}
-
-	/*
-	 * Increment the last counter.  If it overflows, reset to 0
-	 * and increment the one before it.
-	 */
-	m = n-1;
-	counters[m]++;
-	while (counters[m] == RARRAY_LEN(arrays[m])) {
-	    counters[m] = 0;
-	    /* If the first counter overflows, we are done */
-	    if (--m < 0) goto done;
-	    counters[m]++;
-	}
+        int m;
+        /* fill in one subarray */
+        VALUE subarray = rb_ary_new2(n);
+        for (j = 0; j < n; j++) {
+            rb_ary_push(subarray, rb_ary_entry(arrays[j], counters[j]));
+        }
+
+        /* put it on the result array */
+        if (NIL_P(result)) {
+            FL_SET(t0, RARRAY_SHARED_ROOT_FLAG);
+            rb_yield(subarray);
+            if (!FL_TEST(t0, RARRAY_SHARED_ROOT_FLAG)) {
+                rb_raise(rb_eRuntimeError, "product reentered");
+            }
+            else {
+                FL_UNSET(t0, RARRAY_SHARED_ROOT_FLAG);
+            }
+        }
+        else {
+            rb_ary_push(result, subarray);
+        }
+
+        /*
+         * Increment the last counter.  If it overflows, reset to 0
+         * and increment the one before it.
+         */
+        m = n-1;
+        counters[m]++;
+        while (counters[m] == RARRAY_LEN(arrays[m])) {
+            counters[m] = 0;
+            /* If the first counter overflows, we are done */
+            if (--m < 0) goto done;
+            counters[m]++;
+        }
     }
+
 done:
-    tmpary_discard(t0);
-    tmpbuf_discard(t1);
+    ALLOCV_END(t1);
 
     return NIL_P(result) ? ary : result;
 }
 
 /*
  *  call-seq:
- *     ary.take(n)               -> new_ary
+ *    array.take(n) -> new_array
  *
- *  Returns first +n+ elements from the array.
+ *  Returns a new \Array containing the first +n+ element of +self+,
+ *  where +n+ is a non-negative \Integer;
+ *  does not modify +self+.
  *
- *  If a negative number is given, raises an ArgumentError.
+ *  Examples:
  *
- *  See also Array#drop
- *
- *     a = [1, 2, 3, 4, 5, 0]
- *     a.take(3)             #=> [1, 2, 3]
+ *    a = [0, 1, 2, 3, 4, 5]
+ *    a.take(1) # => [0]
+ *    a.take(2) # => [0, 1]
+ *    a.take(50) # => [0, 1, 2, 3, 4, 5]
+ *    a # => [0, 1, 2, 3, 4, 5]
  *
  */
 
@@ -5510,25 +7757,31 @@ rb_ary_take(VALUE obj, VALUE n)
 {
     long len = NUM2LONG(n);
     if (len < 0) {
-	rb_raise(rb_eArgError, "attempt to take negative size");
+        rb_raise(rb_eArgError, "attempt to take negative size");
     }
     return rb_ary_subseq(obj, 0, len);
 }
 
 /*
  *  call-seq:
- *     ary.take_while { |obj| block }  -> new_ary
- *     ary.take_while                  -> Enumerator
+ *    array.take_while {|element| ... } -> new_array
+ *    array.take_while -> new_enumerator
+ *
+ *  Returns a new \Array containing zero or more leading elements of +self+;
+ *  does not modify +self+.
  *
- *  Passes elements to the block until the block returns +nil+ or +false+, then
- *  stops iterating and returns an array of all prior elements.
+ *  With a block given, calls the block with each successive element of +self+;
+ *  stops if the block returns +false+ or +nil+;
+ *  returns a new \Array containing those elements for which the block returned a truthy value:
  *
- *  If no block is given, an Enumerator is returned instead.
+ *    a = [0, 1, 2, 3, 4, 5]
+ *    a.take_while {|element| element < 3 } # => [0, 1, 2]
+ *    a.take_while {|element| true } # => [0, 1, 2, 3, 4, 5]
+ *    a # => [0, 1, 2, 3, 4, 5]
  *
- *  See also Array#drop_while
+ *  With no block given, returns a new \Enumerator:
  *
- *     a = [1, 2, 3, 4, 5, 0]
- *     a.take_while { |i| i < 3 }  #=> [1, 2]
+ *    [0, 1].take_while # => #<Enumerator: [0, 1]:take_while>
  *
  */
 
@@ -5539,24 +7792,25 @@ rb_ary_take_while(VALUE ary)
 
     RETURN_ENUMERATOR(ary, 0, 0);
     for (i = 0; i < RARRAY_LEN(ary); i++) {
-	if (!RTEST(rb_yield(RARRAY_AREF(ary, i)))) break;
+        if (!RTEST(rb_yield(RARRAY_AREF(ary, i)))) break;
     }
     return rb_ary_take(ary, LONG2FIX(i));
 }
 
 /*
  *  call-seq:
- *     ary.drop(n)               -> new_ary
- *
- *  Drops first +n+ elements from +ary+ and returns the rest of the elements in
- *  an array.
+ *    array.drop(n) -> new_array
  *
- *  If a negative number is given, raises an ArgumentError.
+ *  Returns a new \Array containing all but the first +n+ element of +self+,
+ *  where +n+ is a non-negative \Integer;
+ *  does not modify +self+.
  *
- *  See also Array#take
+ *  Examples:
  *
- *     a = [1, 2, 3, 4, 5, 0]
- *     a.drop(3)             #=> [4, 5, 0]
+ *    a = [0, 1, 2, 3, 4, 5]
+ *    a.drop(0) # => [0, 1, 2, 3, 4, 5]
+ *    a.drop(1) # => [1, 2, 3, 4, 5]
+ *    a.drop(2) # => [2, 3, 4, 5]
  *
  */
 
@@ -5566,29 +7820,32 @@ rb_ary_drop(VALUE ary, VALUE n)
     VALUE result;
     long pos = NUM2LONG(n);
     if (pos < 0) {
-	rb_raise(rb_eArgError, "attempt to drop negative size");
+        rb_raise(rb_eArgError, "attempt to drop negative size");
     }
 
     result = rb_ary_subseq(ary, pos, RARRAY_LEN(ary));
-    if (result == Qnil) result = rb_ary_new();
+    if (NIL_P(result)) result = rb_ary_new();
     return result;
 }
 
 /*
  *  call-seq:
- *     ary.drop_while { |obj| block }   -> new_ary
- *     ary.drop_while                  -> Enumerator
+ *    array.drop_while {|element| ... } -> new_array
+ *    array.drop_while -> new_enumerator
+
+ *  Returns a new \Array containing zero or more trailing elements of +self+;
+ *  does not modify +self+.
  *
- *  Drops elements up to, but not including, the first element for which the
- *  block returns +nil+ or +false+ and returns an array containing the
- *  remaining elements.
+ *  With a block given, calls the block with each successive element of +self+;
+ *  stops if the block returns +false+ or +nil+;
+ *  returns a new \Array _omitting_ those elements for which the block returned a truthy value:
  *
- *  If no block is given, an Enumerator is returned instead.
+ *    a = [0, 1, 2, 3, 4, 5]
+ *    a.drop_while {|element| element < 3 } # => [3, 4, 5]
  *
- *  See also Array#take_while
+ *  With no block given, returns a new \Enumerator:
  *
- *     a = [1, 2, 3, 4, 5, 0]
- *     a.drop_while {|i| i < 3 }   #=> [3, 4, 5, 0]
+ *    [0, 1].drop_while # => # => #<Enumerator: [0, 1]:drop_while>
  *
  */
 
@@ -5599,53 +7856,286 @@ rb_ary_drop_while(VALUE ary)
 
     RETURN_ENUMERATOR(ary, 0, 0);
     for (i = 0; i < RARRAY_LEN(ary); i++) {
-	if (!RTEST(rb_yield(RARRAY_AREF(ary, i)))) break;
+        if (!RTEST(rb_yield(RARRAY_AREF(ary, i)))) break;
     }
     return rb_ary_drop(ary, LONG2FIX(i));
 }
 
 /*
  *  call-seq:
- *     ary.any? [{ |obj| block }]   -> true or false
+ *    array.any? -> true or false
+ *    array.any? {|element| ... } -> true or false
+ *    array.any?(obj) -> true or false
+ *
+ *  Returns +true+ if any element of +self+ meets a given criterion.
+ *
+ *  With no block given and no argument, returns +true+ if +self+ has any truthy element,
+ *  +false+ otherwise:
+ *
+ *    [nil, 0, false].any? # => true
+ *    [nil, false].any? # => false
+ *    [].any? # => false
+ *
+ *  With a block given and no argument, calls the block with each element in +self+;
+ *  returns +true+ if the block returns any truthy value, +false+ otherwise:
+ *
+ *    [0, 1, 2].any? {|element| element > 1 } # => true
+ *    [0, 1, 2].any? {|element| element > 2 } # => false
+ *
+ *  If argument +obj+ is given, returns +true+ if +obj+.<tt>===</tt> any element,
+ *  +false+ otherwise:
  *
- *  See also Enumerable#any?
+ *    ['food', 'drink'].any?(/foo/) # => true
+ *    ['food', 'drink'].any?(/bar/) # => false
+ *    [].any?(/foo/) # => false
+ *    [0, 1, 2].any?(1) # => true
+ *    [0, 1, 2].any?(3) # => false
+ *
+ *  Related: Enumerable#any?
  */
 
 static VALUE
-rb_ary_any_p(VALUE ary)
+rb_ary_any_p(int argc, VALUE *argv, VALUE ary)
 {
     long i, len = RARRAY_LEN(ary);
-    const VALUE *ptr = RARRAY_CONST_PTR(ary);
 
+    rb_check_arity(argc, 0, 1);
     if (!len) return Qfalse;
-    if (!rb_block_given_p()) {
-	for (i = 0; i < len; ++i) if (RTEST(ptr[i])) return Qtrue;
+    if (argc) {
+        if (rb_block_given_p()) {
+            rb_warn("given block not used");
+        }
+        for (i = 0; i < RARRAY_LEN(ary); ++i) {
+            if (RTEST(rb_funcall(argv[0], idEqq, 1, RARRAY_AREF(ary, i)))) return Qtrue;
+        }
+    }
+    else if (!rb_block_given_p()) {
+        for (i = 0; i < len; ++i) {
+            if (RTEST(RARRAY_AREF(ary, i))) return Qtrue;
+        }
     }
     else {
-	for (i = 0; i < RARRAY_LEN(ary); ++i) {
-	    if (RTEST(rb_yield(RARRAY_AREF(ary, i)))) return Qtrue;
-	}
+        for (i = 0; i < RARRAY_LEN(ary); ++i) {
+            if (RTEST(rb_yield(RARRAY_AREF(ary, i)))) return Qtrue;
+        }
     }
     return Qfalse;
 }
 
 /*
- * call-seq:
- *   ary.dig(idx, ...)                 -> object
+ *  call-seq:
+ *    array.all? -> true or false
+ *    array.all? {|element| ... } -> true or false
+ *    array.all?(obj) -> true or false
+ *
+ *  Returns +true+ if all elements of +self+ meet a given criterion.
+ *
+ *  With no block given and no argument, returns +true+ if +self+ contains only truthy elements,
+ *  +false+ otherwise:
+ *
+ *    [0, 1, :foo].all? # => true
+ *    [0, nil, 2].all? # => false
+ *    [].all? # => true
+ *
+ *  With a block given and no argument, calls the block with each element in +self+;
+ *  returns +true+ if the block returns only truthy values, +false+ otherwise:
  *
- * Extracts the nested value specified by the sequence of <i>idx</i>
- * objects by calling +dig+ at each step, returning +nil+ if any
- * intermediate step is +nil+.
+ *    [0, 1, 2].all? { |element| element < 3 } # => true
+ *    [0, 1, 2].all? { |element| element < 2 } # => false
  *
- *   a = [[1, [2, 3]]]
+ *  If argument +obj+ is given, returns +true+ if <tt>obj.===</tt> every element, +false+ otherwise:
  *
- *   a.dig(0, 1, 1)                    #=> 3
- *   a.dig(1, 2, 3)                    #=> nil
- *   a.dig(0, 0, 0)                    #=> TypeError: Fixnum does not have #dig method
- *   [42, {foo: :bar}].dig(1, :foo)    #=> :bar
+ *    ['food', 'fool', 'foot'].all?(/foo/) # => true
+ *    ['food', 'drink'].all?(/bar/) # => false
+ *    [].all?(/foo/) # => true
+ *    [0, 0, 0].all?(0) # => true
+ *    [0, 1, 2].all?(1) # => false
+ *
+ *  Related: Enumerable#all?
  */
 
-VALUE
+static VALUE
+rb_ary_all_p(int argc, VALUE *argv, VALUE ary)
+{
+    long i, len = RARRAY_LEN(ary);
+
+    rb_check_arity(argc, 0, 1);
+    if (!len) return Qtrue;
+    if (argc) {
+        if (rb_block_given_p()) {
+            rb_warn("given block not used");
+        }
+        for (i = 0; i < RARRAY_LEN(ary); ++i) {
+            if (!RTEST(rb_funcall(argv[0], idEqq, 1, RARRAY_AREF(ary, i)))) return Qfalse;
+        }
+    }
+    else if (!rb_block_given_p()) {
+        for (i = 0; i < len; ++i) {
+            if (!RTEST(RARRAY_AREF(ary, i))) return Qfalse;
+        }
+    }
+    else {
+        for (i = 0; i < RARRAY_LEN(ary); ++i) {
+            if (!RTEST(rb_yield(RARRAY_AREF(ary, i)))) return Qfalse;
+        }
+    }
+    return Qtrue;
+}
+
+/*
+ *  call-seq:
+ *    array.none? -> true or false
+ *    array.none? {|element| ... } -> true or false
+ *    array.none?(obj) -> true or false
+ *
+ *  Returns +true+ if no element of +self+ meet a given criterion.
+ *
+ *  With no block given and no argument, returns +true+ if +self+ has no truthy elements,
+ *  +false+ otherwise:
+ *
+ *    [nil, false].none? # => true
+ *    [nil, 0, false].none? # => false
+ *    [].none? # => true
+ *
+ *  With a block given and no argument, calls the block with each element in +self+;
+ *  returns +true+ if the block returns no truthy value, +false+ otherwise:
+ *
+ *    [0, 1, 2].none? {|element| element > 3 } # => true
+ *    [0, 1, 2].none? {|element| element > 1 } # => false
+ *
+ *  If argument +obj+ is given, returns +true+ if <tt>obj.===</tt> no element, +false+ otherwise:
+ *
+ *    ['food', 'drink'].none?(/bar/) # => true
+ *    ['food', 'drink'].none?(/foo/) # => false
+ *    [].none?(/foo/) # => true
+ *    [0, 1, 2].none?(3) # => true
+ *    [0, 1, 2].none?(1) # => false
+ *
+ *  Related: Enumerable#none?
+ */
+
+static VALUE
+rb_ary_none_p(int argc, VALUE *argv, VALUE ary)
+{
+    long i, len = RARRAY_LEN(ary);
+
+    rb_check_arity(argc, 0, 1);
+    if (!len) return Qtrue;
+    if (argc) {
+        if (rb_block_given_p()) {
+            rb_warn("given block not used");
+        }
+        for (i = 0; i < RARRAY_LEN(ary); ++i) {
+            if (RTEST(rb_funcall(argv[0], idEqq, 1, RARRAY_AREF(ary, i)))) return Qfalse;
+        }
+    }
+    else if (!rb_block_given_p()) {
+        for (i = 0; i < len; ++i) {
+            if (RTEST(RARRAY_AREF(ary, i))) return Qfalse;
+        }
+    }
+    else {
+        for (i = 0; i < RARRAY_LEN(ary); ++i) {
+            if (RTEST(rb_yield(RARRAY_AREF(ary, i)))) return Qfalse;
+        }
+    }
+    return Qtrue;
+}
+
+/*
+ *  call-seq:
+ *    array.one? -> true or false
+ *    array.one? {|element| ... } -> true or false
+ *    array.one?(obj) -> true or false
+ *
+ *  Returns +true+ if exactly one element of +self+ meets a given criterion.
+ *
+ *  With no block given and no argument, returns +true+ if +self+ has exactly one truthy element,
+ *  +false+ otherwise:
+ *
+ *    [nil, 0].one? # => true
+ *    [0, 0].one? # => false
+ *    [nil, nil].one? # => false
+ *    [].one? # => false
+ *
+ *  With a block given and no argument, calls the block with each element in +self+;
+ *  returns +true+ if the block a truthy value for exactly one element, +false+ otherwise:
+ *
+ *    [0, 1, 2].one? {|element| element > 0 } # => false
+ *    [0, 1, 2].one? {|element| element > 1 } # => true
+ *    [0, 1, 2].one? {|element| element > 2 } # => false
+ *
+ *  If argument +obj+ is given, returns +true+ if <tt>obj.===</tt> exactly one element,
+ *  +false+ otherwise:
+ *
+ *    [0, 1, 2].one?(0) # => true
+ *    [0, 0, 1].one?(0) # => false
+ *    [1, 1, 2].one?(0) # => false
+ *    ['food', 'drink'].one?(/bar/) # => false
+ *    ['food', 'drink'].one?(/foo/) # => true
+ *    [].one?(/foo/) # => false
+ *
+ *  Related: Enumerable#one?
+ */
+
+static VALUE
+rb_ary_one_p(int argc, VALUE *argv, VALUE ary)
+{
+    long i, len = RARRAY_LEN(ary);
+    VALUE result = Qfalse;
+
+    rb_check_arity(argc, 0, 1);
+    if (!len) return Qfalse;
+    if (argc) {
+        if (rb_block_given_p()) {
+            rb_warn("given block not used");
+        }
+        for (i = 0; i < RARRAY_LEN(ary); ++i) {
+            if (RTEST(rb_funcall(argv[0], idEqq, 1, RARRAY_AREF(ary, i)))) {
+                if (result) return Qfalse;
+                result = Qtrue;
+            }
+        }
+    }
+    else if (!rb_block_given_p()) {
+        for (i = 0; i < len; ++i) {
+            if (RTEST(RARRAY_AREF(ary, i))) {
+                if (result) return Qfalse;
+                result = Qtrue;
+            }
+        }
+    }
+    else {
+        for (i = 0; i < RARRAY_LEN(ary); ++i) {
+            if (RTEST(rb_yield(RARRAY_AREF(ary, i)))) {
+                if (result) return Qfalse;
+                result = Qtrue;
+            }
+        }
+    }
+    return result;
+}
+
+/*
+ *  call-seq:
+ *    array.dig(index, *identifiers) -> object
+ *
+ *  Finds and returns the object in nested objects
+ *  that is specified by +index+ and +identifiers+.
+ *  The nested objects may be instances of various classes.
+ *  See {Dig Methods}[rdoc-ref:dig_methods.rdoc].
+ *
+ *  Examples:
+ *
+ *    a = [:foo, [:bar, :baz, [:bat, :bam]]]
+ *    a.dig(1) # => [:bar, :baz, [:bat, :bam]]
+ *    a.dig(1, 2) # => [:bat, :bam]
+ *    a.dig(1, 2, 0) # => :bat
+ *    a.dig(1, 2, 3) # => nil
+ *
+ */
+
+static VALUE
 rb_ary_dig(int argc, VALUE *argv, VALUE self)
 {
     rb_check_arity(argc, 1, UNLIMITED_ARGUMENTS);
@@ -5655,44 +8145,57 @@ rb_ary_dig(int argc, VALUE *argv, VALUE self)
     return rb_obj_dig(argc, argv, self, Qnil);
 }
 
+static inline VALUE
+finish_exact_sum(long n, VALUE r, VALUE v, int z)
+{
+    if (n != 0)
+        v = rb_fix_plus(LONG2FIX(n), v);
+    if (!UNDEF_P(r)) {
+        v = rb_rational_plus(r, v);
+    }
+    else if (!n && z) {
+        v = rb_fix_plus(LONG2FIX(0), v);
+    }
+    return v;
+}
+
 /*
  * call-seq:
- *   ary.sum(init=0)                    -> number
- *   ary.sum(init=0) {|e| expr }        -> number
- *
- * Returns the sum of elements.
- * For example, [e1, e2, e3].sum returns init + e1 + e2 + e3.
+ *   array.sum(init = 0) -> object
+ *   array.sum(init = 0) {|element| ... } -> object
  *
- * If a block is given, the block is applied to each element
- * before addition.
+ *  When no block is given, returns the object equivalent to:
  *
- * If <i>ary</i> is empty, it returns <i>init</i>.
+ *    sum = init
+ *    array.each {|element| sum += element }
+ *    sum
  *
- *   [].sum                             #=> 0
- *   [].sum(0.0)                        #=> 0.0
- *   [1, 2, 3].sum                      #=> 6
- *   [3, 5.5].sum                       #=> 8.5
- *   [2.5, 3.0].sum(0.0) {|e| e * e }   #=> 15.25
- *   [Object.new].sum                   #=> TypeError
+ *  For example, <tt>[e1, e2, e3].sum</tt> returns <tt>init + e1 + e2 + e3</tt>.
  *
- * The (arithmetic) mean value of an array can be obtained as follows.
+ *  Examples:
  *
- *   mean = ary.sum(0.0) / ary.length
+ *    a = [0, 1, 2, 3]
+ *    a.sum # => 6
+ *    a.sum(100) # => 106
  *
- * This method can be used for non-numeric objects by
- * explicit <i>init</i> argument.
+ *  The elements need not be numeric, but must be <tt>+</tt>-compatible
+ *  with each other and with +init+:
  *
- *   ["a", "b", "c"].sum("")            #=> "abc"
- *   [[1], [[2]], [3]].sum([])          #=> [1, [2], 3]
+ *    a = ['abc', 'def', 'ghi']
+ *    a.sum('jkl') # => "jklabcdefghi"
  *
- * However, Array#join and Array#flatten is faster than Array#sum.
+ *  When a block is given, it is called with each element
+ *  and the block's return value (instead of the element itself) is used as the addend:
  *
- *   ["a", "b", "c"].join               #=> "abc"
- *   [[1], [[2]], [3]].flatten(1)       #=> [1, [2], 3]
+ *    a = ['zero', 1, :two]
+ *    s = a.sum('Coerced and concatenated: ') {|element| element.to_s }
+ *    s # => "Coerced and concatenated: zero1two"
  *
+ *  Notes:
  *
- * Array#sum method may not respect method redefinition of "+" methods
- * such as Fixnum#+.
+ *  - Array#join and Array#flatten may be faster than Array#sum
+ *    for an \Array of Strings or an \Array of Arrays.
+ *  - Array#sum method may not respect method redefinition of "+" methods such as Integer#+.
  *
  */
 
@@ -5703,8 +8206,7 @@ rb_ary_sum(int argc, VALUE *argv, VALUE ary)
     long i, n;
     int block_given;
 
-    if (rb_scan_args(argc, argv, "01", &v) == 0)
-        v = LONG2FIX(0);
+    v = (rb_check_arity(argc, 0, 1) ? argv[0] : LONG2FIX(0));
 
     block_given = rb_block_given_p();
 
@@ -5724,10 +8226,10 @@ rb_ary_sum(int argc, VALUE *argv, VALUE ary)
                 n = 0;
             }
         }
-        else if (RB_TYPE_P(e, T_BIGNUM))
+        else if (RB_BIGNUM_TYPE_P(e))
             v = rb_big_plus(e, v);
         else if (RB_TYPE_P(e, T_RATIONAL)) {
-            if (r == Qundef)
+            if (UNDEF_P(r))
                 r = e;
             else
                 r = rb_rational_plus(r, e);
@@ -5735,41 +8237,24 @@ rb_ary_sum(int argc, VALUE *argv, VALUE ary)
         else
             goto not_exact;
     }
-    if (n != 0)
-        v = rb_fix_plus(LONG2FIX(n), v);
-    if (r != Qundef) {
-        /* r can be a Integer when mathn is loaded */
-        if (FIXNUM_P(r))
-            v = rb_fix_plus(r, v);
-        else if (RB_TYPE_P(r, T_BIGNUM))
-            v = rb_big_plus(r, v);
-        else
-            v = rb_rational_plus(r, v);
-    }
+    v = finish_exact_sum(n, r, v, argc!=0);
     return v;
 
   not_exact:
-    if (n != 0)
-        v = rb_fix_plus(LONG2FIX(n), v);
-    if (r != Qundef) {
-        /* r can be a Integer when mathn is loaded */
-        if (FIXNUM_P(r))
-            v = rb_fix_plus(r, v);
-        else if (RB_TYPE_P(r, T_BIGNUM))
-            v = rb_big_plus(r, v);
-        else
-            v = rb_rational_plus(r, v);
-    }
+    v = finish_exact_sum(n, r, v, i!=0);
 
     if (RB_FLOAT_TYPE_P(e)) {
-        /* Kahan's compensated summation algorithm */
+        /*
+         * Kahan-Babuska balancing compensated summation algorithm
+         * See https://link.springer.com/article/10.1007/s00607-005-0139-x
+         */
         double f, c;
+        double x, t;
 
         f = NUM2DBL(v);
         c = 0.0;
         goto has_float_value;
         for (; i < RARRAY_LEN(ary); i++) {
-            double x, y, t;
             e = RARRAY_AREF(ary, i);
             if (block_given)
                 e = rb_yield(e);
@@ -5778,18 +8263,35 @@ rb_ary_sum(int argc, VALUE *argv, VALUE ary)
                 x = RFLOAT_VALUE(e);
             else if (FIXNUM_P(e))
                 x = FIX2LONG(e);
-            else if (RB_TYPE_P(e, T_BIGNUM))
+            else if (RB_BIGNUM_TYPE_P(e))
                 x = rb_big2dbl(e);
             else if (RB_TYPE_P(e, T_RATIONAL))
                 x = rb_num2dbl(e);
             else
                 goto not_float;
 
-            y = x - c;
-            t = f + y;
-            c = (t - f) - y;
+            if (isnan(f)) continue;
+            if (isnan(x)) {
+                f = x;
+                continue;
+            }
+            if (isinf(x)) {
+                if (isinf(f) && signbit(x) != signbit(f))
+                    f = NAN;
+                else
+                    f = x;
+                continue;
+            }
+            if (isinf(f)) continue;
+
+            t = f + x;
+            if (fabs(f) >= fabs(x))
+                c += ((f - t) + x);
+            else
+                c += ((x - t) + f);
             f = t;
         }
+        f += c;
         return DBL2NUM(f);
 
       not_float:
@@ -5807,55 +8309,135 @@ rb_ary_sum(int argc, VALUE *argv, VALUE ary)
     return v;
 }
 
+static VALUE
+rb_ary_deconstruct(VALUE ary)
+{
+    return ary;
+}
+
 /*
- *  Arrays are ordered, integer-indexed collections of any object.
+ *  An \Array is an ordered, integer-indexed collection of objects, called _elements_.
+ *  Any object (even another array) may be an array element,
+ *  and an array can contain objects of different types.
+ *
+ *  == \Array Indexes
+ *
+ *  \Array indexing starts at 0, as in C or Java.
+ *
+ *  A positive index is an offset from the first element:
+ *
+ *  - Index 0 indicates the first element.
+ *  - Index 1 indicates the second element.
+ *  - ...
+ *
+ *  A negative index is an offset, backwards, from the end of the array:
+ *
+ *  - Index -1 indicates the last element.
+ *  - Index -2 indicates the next-to-last element.
+ *  - ...
+ *
+ *  A non-negative index is <i>in range</i> if and only if it is smaller than
+ *  the size of the array.  For a 3-element array:
+ *
+ *  - Indexes 0 through 2 are in range.
+ *  - Index 3 is out of range.
+ *
+ *  A negative index is <i>in range</i> if and only if its absolute value is
+ *  not larger than the size of the array.  For a 3-element array:
+ *
+ *  - Indexes -1 through -3 are in range.
+ *  - Index -4 is out of range.
+ *
+ *  Although the effective index into an array is always an integer,
+ *  some methods (both within and outside of class \Array)
+ *  accept one or more non-integer arguments that are
+ *  {integer-convertible objects}[rdoc-ref:implicit_conversion.rdoc@Integer-Convertible+Objects].
  *
- *  Array indexing starts at 0, as in C or Java.  A negative index is assumed
- *  to be relative to the end of the array---that is, an index of -1 indicates
- *  the last element of the array, -2 is the next to last element in the
- *  array, and so on.
  *
  *  == Creating Arrays
  *
- *  A new array can be created by using the literal constructor
- *  <code>[]</code>.  Arrays can contain different types of objects.  For
- *  example, the array below contains an Integer, a String and a Float:
+ *  You can create an \Array object explicitly with:
+ *
+ *  - An {array literal}[rdoc-ref:literals.rdoc@Array+Literals]:
+ *
+ *      [1, 'one', :one, [2, 'two', :two]]
+ *
+ *  - A {%w or %W: string-array Literal}[rdoc-ref:literals.rdoc@25w+and+-25W-3A+String-Array+Literals]:
+ *
+ *      %w[foo bar baz] # => ["foo", "bar", "baz"]
+ *      %w[1 % *]       # => ["1", "%", "*"]
  *
- *     ary = [1, "two", 3.0] #=> [1, "two", 3.0]
+ *  - A {%i pr %I: symbol-array Literal}[rdoc-ref:literals.rdoc@25i+and+-25I-3A+Symbol-Array+Literals]:
  *
- *  An array can also be created by explicitly calling Array.new with zero, one
- *  (the initial size of the Array) or two arguments (the initial size and a
- *  default object).
+ *      %i[foo bar baz] # => [:foo, :bar, :baz]
+ *      %i[1 % *]       # => [:"1", :%, :*]
  *
- *     ary = Array.new    #=> []
- *     Array.new(3)       #=> [nil, nil, nil]
- *     Array.new(3, true) #=> [true, true, true]
+ *  - \Method Kernel#Array:
  *
- *  Note that the second argument populates the array with references to the
- *  same object.  Therefore, it is only recommended in cases when you need to
- *  instantiate arrays with natively immutable objects such as Symbols,
- *  numbers, true or false.
+ *      Array(["a", "b"])             # => ["a", "b"]
+ *      Array(1..5)                   # => [1, 2, 3, 4, 5]
+ *      Array(key: :value)            # => [[:key, :value]]
+ *      Array(nil)                    # => []
+ *      Array(1)                      # => [1]
+ *      Array({:a => "a", :b => "b"}) # => [[:a, "a"], [:b, "b"]]
  *
- *  To create an array with separate objects a block can be passed instead.
- *  This method is safe to use with mutable objects such as hashes, strings or
- *  other arrays:
+ *  - \Method Array.new:
  *
- *     Array.new(4) { Hash.new } #=> [{}, {}, {}, {}]
+ *      Array.new               # => []
+ *      Array.new(3)            # => [nil, nil, nil]
+ *      Array.new(4) {Hash.new} # => [{}, {}, {}, {}]
+ *      Array.new(3, true)      # => [true, true, true]
  *
- *  This is also a quick way to build up multi-dimensional arrays:
+ *    Note that the last example above populates the array
+ *    with references to the same object.
+ *    This is recommended only in cases where that object is a natively immutable object
+ *    such as a symbol, a numeric, +nil+, +true+, or +false+.
  *
- *     empty_table = Array.new(3) { Array.new(3) }
- *     #=> [[nil, nil, nil], [nil, nil, nil], [nil, nil, nil]]
+ *    Another way to create an array with various objects, using a block;
+ *    this usage is safe for mutable objects such as hashes, strings or
+ *    other arrays:
  *
- *  An array can also be created by using the Array() method, provided by
- *  Kernel, which tries to call #to_ary, then #to_a on its argument.
+ *      Array.new(4) {|i| i.to_s } # => ["0", "1", "2", "3"]
  *
- *	Array({:a => "a", :b => "b"}) #=> [[:a, "a"], [:b, "b"]]
+ *    Here is a way to create a multi-dimensional array:
+ *
+ *      Array.new(3) {Array.new(3)}
+ *      # => [[nil, nil, nil], [nil, nil, nil], [nil, nil, nil]]
+ *
+ *  A number of Ruby methods, both in the core and in the standard library,
+ *  provide instance method +to_a+, which converts an object to an array.
+ *
+ *  - ARGF#to_a
+ *  - Array#to_a
+ *  - Enumerable#to_a
+ *  - Hash#to_a
+ *  - MatchData#to_a
+ *  - NilClass#to_a
+ *  - OptionParser#to_a
+ *  - Range#to_a
+ *  - Set#to_a
+ *  - Struct#to_a
+ *  - Time#to_a
+ *  - Benchmark::Tms#to_a
+ *  - CSV::Table#to_a
+ *  - Enumerator::Lazy#to_a
+ *  - Gem::List#to_a
+ *  - Gem::NameTuple#to_a
+ *  - Gem::Platform#to_a
+ *  - Gem::RequestSet::Lockfile::Tokenizer#to_a
+ *  - Gem::SourceList#to_a
+ *  - OpenSSL::X509::Extension#to_a
+ *  - OpenSSL::X509::Name#to_a
+ *  - Racc::ISet#to_a
+ *  - Rinda::RingFinger#to_a
+ *  - Ripper::Lexer::Elem#to_a
+ *  - RubyVM::InstructionSequence#to_a
+ *  - YAML::DBM#to_a
  *
  *  == Example Usage
  *
  *  In addition to the methods it mixes in through the Enumerable module, the
- *  Array class has proprietary methods for accessing, searching and otherwise
+ *  \Array class has proprietary methods for accessing, searching and otherwise
  *  manipulating arrays.
  *
  *  Some of the more common ones are illustrated below.
@@ -5903,7 +8485,7 @@ rb_ary_sum(int argc, VALUE *argv, VALUE ary)
  *
  *     arr.drop(3) #=> [4, 5, 6]
  *
- *  == Obtaining Information about an Array
+ *  == Obtaining Information about an \Array
  *
  *  Arrays keep track of their own length at all times.  To query an array
  *  about the number of elements it contains, use #length, #count or #size.
@@ -5941,7 +8523,7 @@ rb_ary_sum(int argc, VALUE *argv, VALUE ary)
  *     arr.insert(3, 'orange', 'pear', 'grapefruit')
  *     #=> [0, 1, 2, "orange", "pear", "grapefruit", "apple", 3, 4, 5, 6]
  *
- *  == Removing Items from an Array
+ *  == Removing Items from an \Array
  *
  *  The method #pop removes the last element in an array and returns it:
  *
@@ -5983,15 +8565,15 @@ rb_ary_sum(int argc, VALUE *argv, VALUE ary)
  *
  *  == Iterating over Arrays
  *
- *  Like all classes that include the Enumerable module, Array has an each
+ *  Like all classes that include the Enumerable module, \Array has an each
  *  method, which defines what elements should be iterated over and how.  In
- *  case of Array's #each, all elements in the Array instance are yielded to
+ *  case of Array's #each, all elements in the \Array instance are yielded to
  *  the supplied block in sequence.
  *
  *  Note that this operation leaves the array unchanged.
  *
  *     arr = [1, 2, 3, 4, 5]
- *     arr.each { |a| print a -= 10, " " }
+ *     arr.each {|a| print a -= 10, " "}
  *     # prints: -9 -8 -7 -6 -5
  *     #=> [1, 2, 3, 4, 5]
  *
@@ -6000,18 +8582,19 @@ rb_ary_sum(int argc, VALUE *argv, VALUE ary)
  *
  *     words = %w[first second third fourth fifth sixth]
  *     str = ""
- *     words.reverse_each { |word| str += "#{word} " }
+ *     words.reverse_each {|word| str += "#{word} "}
  *     p str #=> "sixth fifth fourth third second first "
  *
  *  The #map method can be used to create a new array based on the original
  *  array, but with the values modified by the supplied block:
  *
- *     arr.map { |a| 2*a }   #=> [2, 4, 6, 8, 10]
+ *     arr.map {|a| 2*a}     #=> [2, 4, 6, 8, 10]
  *     arr                   #=> [1, 2, 3, 4, 5]
- *     arr.map! { |a| a**2 } #=> [1, 4, 9, 16, 25]
+ *     arr.map! {|a| a**2}   #=> [1, 4, 9, 16, 25]
  *     arr                   #=> [1, 4, 9, 16, 25]
  *
- *  == Selecting Items from an Array
+ *
+ *  == Selecting Items from an \Array
  *
  *  Elements can be selected from an array according to criteria defined in a
  *  block.  The selection can happen in a destructive or a non-destructive
@@ -6022,9 +8605,9 @@ rb_ary_sum(int argc, VALUE *argv, VALUE ary)
  *  === Non-destructive Selection
  *
  *     arr = [1, 2, 3, 4, 5, 6]
- *     arr.select { |a| a > 3 }     #=> [4, 5, 6]
- *     arr.reject { |a| a < 3 }     #=> [3, 4, 5, 6]
- *     arr.drop_while { |a| a < 4 } #=> [4, 5, 6]
+ *     arr.select {|a| a > 3}       #=> [4, 5, 6]
+ *     arr.reject {|a| a < 3}       #=> [3, 4, 5, 6]
+ *     arr.drop_while {|a| a < 4}   #=> [4, 5, 6]
  *     arr                          #=> [1, 2, 3, 4, 5, 6]
  *
  *  === Destructive Selection
@@ -6035,25 +8618,205 @@ rb_ary_sum(int argc, VALUE *argv, VALUE ary)
  *  Similar to #select vs. #reject, #delete_if and #keep_if have the exact
  *  opposite result when supplied with the same block:
  *
- *     arr.delete_if { |a| a < 4 } #=> [4, 5, 6]
+ *     arr.delete_if {|a| a < 4}   #=> [4, 5, 6]
  *     arr                         #=> [4, 5, 6]
  *
  *     arr = [1, 2, 3, 4, 5, 6]
- *     arr.keep_if { |a| a < 4 } #=> [1, 2, 3]
+ *     arr.keep_if {|a| a < 4}   #=> [1, 2, 3]
  *     arr                       #=> [1, 2, 3]
  *
+ *  == What's Here
+ *
+ *  First, what's elsewhere. \Class \Array:
+ *
+ *  - Inherits from {class Object}[rdoc-ref:Object@What-27s+Here].
+ *  - Includes {module Enumerable}[rdoc-ref:Enumerable@What-27s+Here],
+ *    which provides dozens of additional methods.
+ *
+ *  Here, class \Array provides methods that are useful for:
+ *
+ *  - {Creating an Array}[rdoc-ref:Array@Methods+for+Creating+an+Array]
+ *  - {Querying}[rdoc-ref:Array@Methods+for+Querying]
+ *  - {Comparing}[rdoc-ref:Array@Methods+for+Comparing]
+ *  - {Fetching}[rdoc-ref:Array@Methods+for+Fetching]
+ *  - {Assigning}[rdoc-ref:Array@Methods+for+Assigning]
+ *  - {Deleting}[rdoc-ref:Array@Methods+for+Deleting]
+ *  - {Combining}[rdoc-ref:Array@Methods+for+Combining]
+ *  - {Iterating}[rdoc-ref:Array@Methods+for+Iterating]
+ *  - {Converting}[rdoc-ref:Array@Methods+for+Converting]
+ *  - {And more....}[rdoc-ref:Array@Other+Methods]
+ *
+ *  === Methods for Creating an \Array
+ *
+ *  - ::[]: Returns a new array populated with given objects.
+ *  - ::new: Returns a new array.
+ *  - ::try_convert: Returns a new array created from a given object.
+ *
+ *  === Methods for Querying
+ *
+ *  - #length, #size: Returns the count of elements.
+ *  - #include?: Returns whether any element <tt>==</tt> a given object.
+ *  - #empty?: Returns whether there are no elements.
+ *  - #all?: Returns whether all elements meet a given criterion.
+ *  - #any?: Returns whether any element meets a given criterion.
+ *  - #none?: Returns whether no element <tt>==</tt> a given object.
+ *  - #one?: Returns whether exactly one element <tt>==</tt> a given object.
+ *  - #count: Returns the count of elements that meet a given criterion.
+ *  - #find_index, #index: Returns the index of the first element that meets a given criterion.
+ *  - #rindex: Returns the index of the last element that meets a given criterion.
+ *  - #hash: Returns the integer hash code.
+ *
+ *  === Methods for Comparing
+ *
+ *  - #<=>: Returns -1, 0, or 1 * as +self+ is less than, equal to, or
+ *    greater than a given object.
+ *  - #==: Returns whether each element in +self+ is <tt>==</tt> to the corresponding element
+ *    in a given object.
+ *  - #eql?: Returns whether each element in +self+ is <tt>eql?</tt> to the corresponding
+ *    element in a given object.
+
+ *  === Methods for Fetching
+ *
+ *  These methods do not modify +self+.
+ *
+ *  - #[]: Returns one or more elements.
+ *  - #fetch: Returns the element at a given offset.
+ *  - #first: Returns one or more leading elements.
+ *  - #last: Returns one or more trailing elements.
+ *  - #max: Returns one or more maximum-valued elements,
+ *    as determined by <tt><=></tt> or a given block.
+ *  - #min: Returns one or more minimum-valued elements,
+ *    as determined by <tt><=></tt> or a given block.
+ *  - #minmax: Returns the minimum-valued and maximum-valued elements,
+ *    as determined by <tt><=></tt> or a given block.
+ *  - #assoc: Returns the first element that is an array
+ *    whose first element <tt>==</tt> a given object.
+ *  - #rassoc: Returns the first element that is an array
+ *    whose second element <tt>==</tt> a given object.
+ *  - #at: Returns the element at a given offset.
+ *  - #values_at: Returns the elements at given offsets.
+ *  - #dig: Returns the object in nested objects
+ *    that is specified by a given index and additional arguments.
+ *  - #drop: Returns trailing elements as determined by a given index.
+ *  - #take: Returns leading elements as determined by a given index.
+ *  - #drop_while: Returns trailing elements as determined by a given block.
+ *  - #take_while: Returns leading elements as determined by a given block.
+ *  - #slice: Returns consecutive elements as determined by a given argument.
+ *  - #sort: Returns all elements in an order determined by <tt><=></tt> or a given block.
+ *  - #reverse: Returns all elements in reverse order.
+ *  - #compact: Returns an array containing all non-+nil+ elements.
+ *  - #select, #filter: Returns an array containing elements selected by a given block.
+ *  - #uniq: Returns an array containing non-duplicate elements.
+ *  - #rotate: Returns all elements with some rotated from one end to the other.
+ *  - #bsearch: Returns an element selected via a binary search
+ *    as determined by a given block.
+ *  - #bsearch_index: Returns the index of an element selected via a binary search
+ *    as determined by a given block.
+ *  - #sample: Returns one or more random elements.
+ *  - #shuffle: Returns elements in a random order.
+ *
+ *  === Methods for Assigning
+ *
+ *  These methods add, replace, or reorder elements in +self+.
+ *
+ *  - #[]=: Assigns specified elements with a given object.
+ *  - #push, #append, #<<: Appends trailing elements.
+ *  - #unshift, #prepend: Prepends leading elements.
+ *  - #insert: Inserts given objects at a given offset; does not replace elements.
+ *  - #concat: Appends all elements from given arrays.
+ *  - #fill: Replaces specified elements with specified objects.
+ *  - #replace: Replaces the content of +self+ with the content of a given array.
+ *  - #reverse!: Replaces +self+ with its elements reversed.
+ *  - #rotate!: Replaces +self+ with its elements rotated.
+ *  - #shuffle!: Replaces +self+ with its elements in random order.
+ *  - #sort!: Replaces +self+ with its elements sorted,
+ *    as determined by <tt><=></tt> or a given block.
+ *  - #sort_by!: Replaces +self+ with its elements sorted, as determined by a given block.
+ *
+ *  === Methods for Deleting
+ *
+ *  Each of these methods removes elements from +self+:
+ *
+ *  - #pop: Removes and returns the last element.
+ *  - #shift:  Removes and returns the first element.
+ *  - #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.
+ *  - #keep_if: Removes elements not specified by a given block.
+ *  - #reject!: Removes elements specified by a given block.
+ *  - #select!, #filter!: Removes elements not specified by a given block.
+ *  - #slice!: Removes and returns a sequence of elements.
+ *  - #uniq!: Removes duplicates.
+ *
+ *  === Methods for Combining
+ *
+ *  - #&: Returns an array containing elements found both in +self+ and a given array.
+ *  - #intersection: Returns an array containing elements found both in +self+
+ *    and in each given array.
+ *  - #+: Returns an array containing all elements of +self+ followed by all elements of a given array.
+ *  - #-: Returns an array containing all elements of +self+ that are not found in a given array.
+ *  - #|: Returns an array containing all elements of +self+ and all elements of a given array,
+ *    duplicates removed.
+ *  - #union: Returns an array containing all elements of +self+ and all elements of given arrays,
+ *    duplicates removed.
+ *  - #difference: Returns an array containing all elements of +self+ that are not found
+ *    in any of the given arrays..
+ *  - #product: Returns or yields all combinations of elements from +self+ and given arrays.
+ *
+ *  === Methods for Iterating
+ *
+ *  - #each: Passes each element to a given block.
+ *  - #reverse_each:  Passes each element, in reverse order, to a given block.
+ *  - #each_index: Passes each element index to a given block.
+ *  - #cycle: Calls a given block with each element, then does so again,
+ *    for a specified number of times, or forever.
+ *  - #combination: Calls a given block with combinations of elements of +self+;
+ *    a combination does not use the same element more than once.
+ *  - #permutation: Calls a given block with permutations of elements of +self+;
+ *    a permutation does not use the same element more than once.
+ *  - #repeated_combination: Calls a given block with combinations of elements of +self+;
+ *    a combination may use the same element more than once.
+ *  - #repeated_permutation: Calls a given block with permutations of elements of +self+;
+ *    a permutation may use the same element more than once.
+ *
+ *  === Methods for Converting
+ *
+ *  - #map, #collect: Returns an array containing the block return-value for each element.
+ *  - #map!, #collect!: Replaces each element with a block return-value.
+ *  - #flatten: Returns an array that is a recursive flattening of +self+.
+ *  - #flatten!: Replaces each nested array in +self+ with the elements from that array.
+ *  - #inspect, #to_s: Returns a new String containing the elements.
+ *  - #join: Returns a newsString containing the elements joined by the field separator.
+ *  - #to_a: Returns +self+ or a new array containing all elements.
+ *  - #to_ary: Returns +self+.
+ *  - #to_h: Returns a new hash formed from the elements.
+ *  - #transpose: Transposes +self+, which must be an array of arrays.
+ *  - #zip: Returns a new array of arrays containing +self+ and given arrays;
+ *    follow the link for details.
+ *
+ *  === Other Methods
+ *
+ *  - #*: Returns one of the following:
+ *
+ *    - With integer argument +n+, a new array that is the concatenation
+ *      of +n+ copies of +self+.
+ *    - With string argument +field_separator+, a new string that is equivalent to
+ *      <tt>join(field_separator)</tt>.
+ *
+ *  - #abbrev: Returns a hash of unambiguous abbreviations for elements.
+ *  - #pack: Packs the elements into a binary sequence.
+ *  - #sum: Returns a sum of elements according to either <tt>+</tt> or a given block.
  */
 
 void
 Init_Array(void)
 {
-#undef rb_intern
-#define rb_intern(str) rb_intern_const(str)
-
     rb_cArray  = rb_define_class("Array", rb_cObject);
     rb_include_module(rb_cArray, rb_mEnumerable);
 
     rb_define_alloc_func(rb_cArray, empty_ary_alloc);
+    rb_define_singleton_method(rb_cArray, "new", rb_ary_s_new, -1);
     rb_define_singleton_method(rb_cArray, "[]", rb_ary_s_create, -1);
     rb_define_singleton_method(rb_cArray, "try_convert", rb_ary_s_try_convert, 1);
     rb_define_method(rb_cArray, "initialize", rb_ary_initialize, -1);
@@ -6064,7 +8827,6 @@ Init_Array(void)
     rb_define_method(rb_cArray, "to_a", rb_ary_to_a, 0);
     rb_define_method(rb_cArray, "to_h", rb_ary_to_h, 0);
     rb_define_method(rb_cArray, "to_ary", rb_ary_to_ary_m, 0);
-    rb_define_method(rb_cArray, "frozen?",  rb_ary_frozen_p, 0);
 
     rb_define_method(rb_cArray, "==", rb_ary_equal, 1);
     rb_define_method(rb_cArray, "eql?", rb_ary_eql, 1);
@@ -6076,18 +8838,24 @@ Init_Array(void)
     rb_define_method(rb_cArray, "fetch", rb_ary_fetch, -1);
     rb_define_method(rb_cArray, "first", rb_ary_first, -1);
     rb_define_method(rb_cArray, "last", rb_ary_last, -1);
-    rb_define_method(rb_cArray, "concat", rb_ary_concat, 1);
+    rb_define_method(rb_cArray, "concat", rb_ary_concat_multi, -1);
+    rb_define_method(rb_cArray, "union", rb_ary_union_multi, -1);
+    rb_define_method(rb_cArray, "difference", rb_ary_difference_multi, -1);
+    rb_define_method(rb_cArray, "intersection", rb_ary_intersection_multi, -1);
+    rb_define_method(rb_cArray, "intersect?", rb_ary_intersect_p, 1);
     rb_define_method(rb_cArray, "<<", rb_ary_push, 1);
     rb_define_method(rb_cArray, "push", rb_ary_push_m, -1);
+    rb_define_alias(rb_cArray,  "append", "push");
     rb_define_method(rb_cArray, "pop", rb_ary_pop_m, -1);
     rb_define_method(rb_cArray, "shift", rb_ary_shift_m, -1);
     rb_define_method(rb_cArray, "unshift", rb_ary_unshift_m, -1);
+    rb_define_alias(rb_cArray,  "prepend", "unshift");
     rb_define_method(rb_cArray, "insert", rb_ary_insert, -1);
     rb_define_method(rb_cArray, "each", rb_ary_each, 0);
     rb_define_method(rb_cArray, "each_index", rb_ary_each_index, 0);
     rb_define_method(rb_cArray, "reverse_each", rb_ary_reverse_each, 0);
     rb_define_method(rb_cArray, "length", rb_ary_length, 0);
-    rb_define_alias(rb_cArray,  "size", "length");
+    rb_define_method(rb_cArray, "size", rb_ary_length, 0);
     rb_define_method(rb_cArray, "empty?", rb_ary_empty_p, 0);
     rb_define_method(rb_cArray, "find_index", rb_ary_index, -1);
     rb_define_method(rb_cArray, "index", rb_ary_index, -1);
@@ -6106,6 +8874,8 @@ Init_Array(void)
     rb_define_method(rb_cArray, "map!", rb_ary_collect_bang, 0);
     rb_define_method(rb_cArray, "select", rb_ary_select, 0);
     rb_define_method(rb_cArray, "select!", rb_ary_select_bang, 0);
+    rb_define_method(rb_cArray, "filter", rb_ary_select, 0);
+    rb_define_method(rb_cArray, "filter!", rb_ary_select_bang, 0);
     rb_define_method(rb_cArray, "keep_if", rb_ary_keep_if, 0);
     rb_define_method(rb_cArray, "values_at", rb_ary_values_at, -1);
     rb_define_method(rb_cArray, "delete", rb_ary_delete, 1);
@@ -6136,6 +8906,7 @@ Init_Array(void)
 
     rb_define_method(rb_cArray, "max", rb_ary_max, -1);
     rb_define_method(rb_cArray, "min", rb_ary_min, -1);
+    rb_define_method(rb_cArray, "minmax", rb_ary_minmax, 0);
 
     rb_define_method(rb_cArray, "uniq", rb_ary_uniq, 0);
     rb_define_method(rb_cArray, "uniq!", rb_ary_uniq_bang, 0);
@@ -6144,9 +8915,6 @@ Init_Array(void)
     rb_define_method(rb_cArray, "flatten", rb_ary_flatten, -1);
     rb_define_method(rb_cArray, "flatten!", rb_ary_flatten_bang, -1);
     rb_define_method(rb_cArray, "count", rb_ary_count, -1);
-    rb_define_method(rb_cArray, "shuffle!", rb_ary_shuffle_bang, -1);
-    rb_define_method(rb_cArray, "shuffle", rb_ary_shuffle, -1);
-    rb_define_method(rb_cArray, "sample", rb_ary_sample, -1);
     rb_define_method(rb_cArray, "cycle", rb_ary_cycle, -1);
     rb_define_method(rb_cArray, "permutation", rb_ary_permutation, -1);
     rb_define_method(rb_cArray, "combination", rb_ary_combination, 1);
@@ -6160,12 +8928,14 @@ Init_Array(void)
     rb_define_method(rb_cArray, "drop_while", rb_ary_drop_while, 0);
     rb_define_method(rb_cArray, "bsearch", rb_ary_bsearch, 0);
     rb_define_method(rb_cArray, "bsearch_index", rb_ary_bsearch_index, 0);
-    rb_define_method(rb_cArray, "any?", rb_ary_any_p, 0);
+    rb_define_method(rb_cArray, "any?", rb_ary_any_p, -1);
+    rb_define_method(rb_cArray, "all?", rb_ary_all_p, -1);
+    rb_define_method(rb_cArray, "none?", rb_ary_none_p, -1);
+    rb_define_method(rb_cArray, "one?", rb_ary_one_p, -1);
     rb_define_method(rb_cArray, "dig", rb_ary_dig, -1);
     rb_define_method(rb_cArray, "sum", rb_ary_sum, -1);
 
-    id_cmp = rb_intern("<=>");
-    id_random = rb_intern("random");
-    id_div = rb_intern("div");
-    id_power = rb_intern("**");
+    rb_define_method(rb_cArray, "deconstruct", rb_ary_deconstruct, 0);
 }
+
+#include "array.rbinc"
diff --git a/array.rb b/array.rb
new file mode 100644
index 0000000000..b9fa9844e6
--- /dev/null
+++ b/array.rb
@@ -0,0 +1,69 @@
+class Array
+  # call-seq:
+  #    array.shuffle!(random: Random) -> array
+  #
+  # Shuffles the elements of +self+ in place.
+  #    a = [1, 2, 3] #=> [1, 2, 3]
+  #    a.shuffle!    #=> [2, 3, 1]
+  #    a             #=> [2, 3, 1]
+  #
+  # The optional +random+ argument will be used as the random number generator:
+  #    a.shuffle!(random: Random.new(1))  #=> [1, 3, 2]
+  def shuffle!(random: Random)
+    Primitive.rb_ary_shuffle_bang(random)
+  end
+
+  # call-seq:
+  #    array.shuffle(random: Random) -> new_ary
+  #
+  # Returns a new array with elements of +self+ shuffled.
+  #    a = [1, 2, 3] #=> [1, 2, 3]
+  #    a.shuffle     #=> [2, 3, 1]
+  #    a             #=> [1, 2, 3]
+  #
+  # The optional +random+ argument will be used as the random number generator:
+  #    a.shuffle(random: Random.new(1))  #=> [1, 3, 2]
+  def shuffle(random: Random)
+    Primitive.rb_ary_shuffle(random)
+  end
+
+  # call-seq:
+  #    array.sample(random: Random) -> object
+  #    array.sample(n, random: Random) -> new_ary
+  #
+  # Returns random elements from +self+.
+  #
+  # When no arguments are given, returns a random element from +self+:
+  #    a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+  #    a.sample # => 3
+  #    a.sample # => 8
+  # If +self+ is empty, returns +nil+.
+  #
+  # When argument +n+ is given, returns a new \Array containing +n+ random
+  # elements from +self+:
+  #    a.sample(3) # => [8, 9, 2]
+  #    a.sample(6) # => [9, 6, 10, 3, 1, 4]
+  # Returns no more than <tt>a.size</tt> elements
+  # (because no new duplicates are introduced):
+  #    a.sample(a.size * 2) # => [6, 4, 1, 8, 5, 9, 10, 2, 3, 7]
+  # But +self+ may contain duplicates:
+  #    a = [1, 1, 1, 2, 2, 3]
+  #    a.sample(a.size * 2) # => [1, 1, 3, 2, 1, 2]
+  # The argument +n+ must be a non-negative numeric value.
+  # The order of the result array is unrelated to the order of +self+.
+  # Returns a new empty \Array if +self+ is empty.
+  #
+  # The optional +random+ argument will be used as the random number generator:
+  #    a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
+  #    a.sample(random: Random.new(1))     #=> 6
+  #    a.sample(4, random: Random.new(1))  #=> [6, 10, 9, 2]
+  def sample(n = (ary = false), random: Random)
+    if Primitive.mandatory_only?
+      # Primitive.cexpr! %{ rb_ary_sample(self, rb_cRandom, Qfalse, Qfalse) }
+      Primitive.ary_sample0
+    else
+      # Primitive.cexpr! %{ rb_ary_sample(self, random, n, ary) }
+      Primitive.ary_sample(random, n, ary)
+    end
+  end
+end
diff --git a/ast.c b/ast.c
new file mode 100644
index 0000000000..adb7287ed3
--- /dev/null
+++ b/ast.c
@@ -0,0 +1,773 @@
+/* indent-tabs-mode: nil */
+#include "internal.h"
+#include "internal/parse.h"
+#include "internal/symbol.h"
+#include "internal/warnings.h"
+#include "iseq.h"
+#include "node.h"
+#include "ruby.h"
+#include "ruby/encoding.h"
+#include "ruby/util.h"
+#include "vm_core.h"
+
+#include "builtin.h"
+
+static VALUE rb_mAST;
+static VALUE rb_cNode;
+
+struct ASTNodeData {
+    rb_ast_t *ast;
+    const NODE *node;
+};
+
+static void
+node_gc_mark(void *ptr)
+{
+    struct ASTNodeData *data = (struct ASTNodeData *)ptr;
+    rb_gc_mark((VALUE)data->ast);
+}
+
+static size_t
+node_memsize(const void *ptr)
+{
+    struct ASTNodeData *data = (struct ASTNodeData *)ptr;
+    return rb_ast_memsize(data->ast);
+}
+
+static const rb_data_type_t rb_node_type = {
+    "AST/node",
+    {node_gc_mark, RUBY_TYPED_DEFAULT_FREE, node_memsize,},
+    0, 0,
+    RUBY_TYPED_FREE_IMMEDIATELY,
+};
+
+static VALUE rb_ast_node_alloc(VALUE klass);
+
+static void
+setup_node(VALUE obj, rb_ast_t *ast, const NODE *node)
+{
+    struct ASTNodeData *data;
+
+    TypedData_Get_Struct(obj, struct ASTNodeData, &rb_node_type, data);
+    data->ast = ast;
+    data->node = node;
+}
+
+static VALUE
+ast_new_internal(rb_ast_t *ast, const NODE *node)
+{
+    VALUE obj;
+
+    obj = rb_ast_node_alloc(rb_cNode);
+    setup_node(obj, ast, node);
+
+    return obj;
+}
+
+static VALUE rb_ast_parse_str(VALUE str, VALUE keep_script_lines, VALUE error_tolerant, VALUE keep_tokens);
+static VALUE rb_ast_parse_file(VALUE path, VALUE keep_script_lines, VALUE error_tolerant, VALUE keep_tokens);
+
+static VALUE
+ast_parse_new(void)
+{
+    return rb_parser_set_context(rb_parser_new(), NULL, 0);
+}
+
+static VALUE
+ast_parse_done(rb_ast_t *ast)
+{
+    if (!ast->body.root) {
+        rb_ast_dispose(ast);
+        rb_exc_raise(GET_EC()->errinfo);
+    }
+
+    return ast_new_internal(ast, (NODE *)ast->body.root);
+}
+
+static VALUE
+ast_s_parse(rb_execution_context_t *ec, VALUE module, VALUE str, VALUE keep_script_lines, VALUE error_tolerant, VALUE keep_tokens)
+{
+    return rb_ast_parse_str(str, keep_script_lines, error_tolerant, keep_tokens);
+}
+
+static VALUE
+rb_ast_parse_str(VALUE str, VALUE keep_script_lines, VALUE error_tolerant, VALUE keep_tokens)
+{
+    rb_ast_t *ast = 0;
+
+    StringValue(str);
+    VALUE vparser = ast_parse_new();
+    if (RTEST(keep_script_lines)) rb_parser_keep_script_lines(vparser);
+    if (RTEST(error_tolerant)) rb_parser_error_tolerant(vparser);
+    if (RTEST(keep_tokens)) rb_parser_keep_tokens(vparser);
+    ast = rb_parser_compile_string_path(vparser, Qnil, str, 1);
+    return ast_parse_done(ast);
+}
+
+static VALUE
+ast_s_parse_file(rb_execution_context_t *ec, VALUE module, VALUE path, VALUE keep_script_lines, VALUE error_tolerant, VALUE keep_tokens)
+{
+    return rb_ast_parse_file(path, keep_script_lines, error_tolerant, keep_tokens);
+}
+
+static VALUE
+rb_ast_parse_file(VALUE path, VALUE keep_script_lines, VALUE error_tolerant, VALUE keep_tokens)
+{
+    VALUE f;
+    rb_ast_t *ast = 0;
+    rb_encoding *enc = rb_utf8_encoding();
+
+    FilePathValue(path);
+    f = rb_file_open_str(path, "r");
+    rb_funcall(f, rb_intern("set_encoding"), 2, rb_enc_from_encoding(enc), rb_str_new_cstr("-"));
+    VALUE vparser = ast_parse_new();
+    if (RTEST(keep_script_lines)) rb_parser_keep_script_lines(vparser);
+    if (RTEST(error_tolerant))  rb_parser_error_tolerant(vparser);
+    if (RTEST(keep_tokens))  rb_parser_keep_tokens(vparser);
+    ast = rb_parser_compile_file_path(vparser, Qnil, f, 1);
+    rb_io_close(f);
+    return ast_parse_done(ast);
+}
+
+static VALUE
+lex_array(VALUE array, int index)
+{
+    VALUE str = rb_ary_entry(array, index);
+    if (!NIL_P(str)) {
+        StringValue(str);
+        if (!rb_enc_asciicompat(rb_enc_get(str))) {
+            rb_raise(rb_eArgError, "invalid source encoding");
+        }
+    }
+    return str;
+}
+
+static VALUE
+rb_ast_parse_array(VALUE array, VALUE keep_script_lines, VALUE error_tolerant, VALUE keep_tokens)
+{
+    rb_ast_t *ast = 0;
+
+    array = rb_check_array_type(array);
+    VALUE vparser = ast_parse_new();
+    if (RTEST(keep_script_lines)) rb_parser_keep_script_lines(vparser);
+    if (RTEST(error_tolerant)) rb_parser_error_tolerant(vparser);
+    if (RTEST(keep_tokens)) rb_parser_keep_tokens(vparser);
+    ast = rb_parser_compile_generic(vparser, lex_array, Qnil, array, 1);
+    return ast_parse_done(ast);
+}
+
+static VALUE node_children(rb_ast_t*, const NODE*);
+
+static VALUE
+node_find(VALUE self, const int node_id)
+{
+    VALUE ary;
+    long i;
+    struct ASTNodeData *data;
+    TypedData_Get_Struct(self, struct ASTNodeData, &rb_node_type, data);
+
+    if (nd_node_id(data->node) == node_id) return self;
+
+    ary = node_children(data->ast, data->node);
+
+    for (i = 0; i < RARRAY_LEN(ary); i++) {
+        VALUE child = RARRAY_AREF(ary, i);
+
+        if (CLASS_OF(child) == rb_cNode) {
+            VALUE result = node_find(child, node_id);
+            if (RTEST(result)) return result;
+        }
+    }
+
+    return Qnil;
+}
+
+extern VALUE rb_e_script;
+
+static VALUE
+script_lines(VALUE path)
+{
+    VALUE hash, lines;
+    ID script_lines;
+    CONST_ID(script_lines, "SCRIPT_LINES__");
+    if (!rb_const_defined_at(rb_cObject, script_lines)) return Qnil;
+    hash = rb_const_get_at(rb_cObject, script_lines);
+    if (!RB_TYPE_P(hash, T_HASH)) return Qnil;
+    lines = rb_hash_lookup(hash, path);
+    if (!RB_TYPE_P(lines, T_ARRAY)) return Qnil;
+    return lines;
+}
+
+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;
+    }
+
+    return INT2NUM(node_id);
+}
+
+static VALUE
+ast_s_of(rb_execution_context_t *ec, VALUE module, VALUE body, VALUE keep_script_lines, VALUE error_tolerant, VALUE keep_tokens)
+{
+    VALUE node, lines = Qnil;
+    const rb_iseq_t *iseq;
+    int node_id;
+
+    if (rb_frame_info_p(body)) {
+        iseq = rb_get_iseq_from_frame_info(body);
+        node_id = rb_get_node_id_from_frame_info(body);
+    }
+    else {
+        iseq = NULL;
+
+        if (rb_obj_is_proc(body)) {
+            iseq = vm_proc_iseq(body);
+
+            if (!rb_obj_is_iseq((VALUE)iseq)) return Qnil;
+        }
+        else {
+            iseq = rb_method_iseq(body);
+        }
+        if (iseq) {
+            node_id = ISEQ_BODY(iseq)->location.node_id;
+        }
+    }
+
+    if (!iseq) {
+        return Qnil;
+    }
+    lines = ISEQ_BODY(iseq)->variable.script_lines;
+
+    VALUE path = rb_iseq_path(iseq);
+    int e_option = RSTRING_LEN(path) == 2 && memcmp(RSTRING_PTR(path), "-e", 2) == 0;
+
+    if (NIL_P(lines) && rb_iseq_from_eval_p(iseq) && !e_option) {
+        rb_raise(rb_eArgError, "cannot get AST for method defined in eval");
+    }
+
+    if (!NIL_P(lines) || !NIL_P(lines = script_lines(path))) {
+        node = rb_ast_parse_array(lines, keep_script_lines, error_tolerant, keep_tokens);
+    }
+    else if (e_option) {
+        node = rb_ast_parse_str(rb_e_script, keep_script_lines, error_tolerant, keep_tokens);
+    }
+    else {
+        node = rb_ast_parse_file(path, keep_script_lines, error_tolerant, keep_tokens);
+    }
+
+    return node_find(node, node_id);
+}
+
+static VALUE
+rb_ast_node_alloc(VALUE klass)
+{
+    struct ASTNodeData *data;
+    VALUE obj = TypedData_Make_Struct(klass, struct ASTNodeData, &rb_node_type, data);
+
+    return obj;
+}
+
+static const char*
+node_type_to_str(const NODE *node)
+{
+    return (ruby_node_name(nd_type(node)) + rb_strlen_lit("NODE_"));
+}
+
+static VALUE
+ast_node_type(rb_execution_context_t *ec, VALUE self)
+{
+    struct ASTNodeData *data;
+    TypedData_Get_Struct(self, struct ASTNodeData, &rb_node_type, data);
+
+    return rb_sym_intern_ascii_cstr(node_type_to_str(data->node));
+}
+
+static VALUE
+ast_node_node_id(rb_execution_context_t *ec, VALUE self)
+{
+    struct ASTNodeData *data;
+    TypedData_Get_Struct(self, struct ASTNodeData, &rb_node_type, data);
+
+    return INT2FIX(nd_node_id(data->node));
+}
+
+#define NEW_CHILD(ast, node) node ? ast_new_internal(ast, node) : Qnil
+
+static VALUE
+rb_ary_new_from_node_args(rb_ast_t *ast, long n, ...)
+{
+    va_list ar;
+    VALUE ary;
+    long i;
+
+    ary = rb_ary_new2(n);
+
+    va_start(ar, n);
+    for (i=0; i<n; i++) {
+        NODE *node;
+        node = va_arg(ar, NODE *);
+        rb_ary_push(ary, NEW_CHILD(ast, node));
+    }
+    va_end(ar);
+    return ary;
+}
+
+static VALUE
+dump_block(rb_ast_t *ast, const NODE *node)
+{
+    VALUE ary = rb_ary_new();
+    do {
+        rb_ary_push(ary, NEW_CHILD(ast, node->nd_head));
+    } while (node->nd_next &&
+        nd_type_p(node->nd_next, NODE_BLOCK) &&
+        (node = node->nd_next, 1));
+    if (node->nd_next) {
+        rb_ary_push(ary, NEW_CHILD(ast, node->nd_next));
+    }
+
+    return ary;
+}
+
+static VALUE
+dump_array(rb_ast_t *ast, const NODE *node)
+{
+    VALUE ary = rb_ary_new();
+    rb_ary_push(ary, NEW_CHILD(ast, node->nd_head));
+
+    while (node->nd_next && nd_type_p(node->nd_next, NODE_LIST)) {
+        node = node->nd_next;
+        rb_ary_push(ary, NEW_CHILD(ast, node->nd_head));
+    }
+    rb_ary_push(ary, NEW_CHILD(ast, node->nd_next));
+
+    return ary;
+}
+
+static VALUE
+var_name(ID id)
+{
+    if (!id) return Qnil;
+    if (!rb_id2str(id)) return Qnil;
+    return ID2SYM(id);
+}
+
+static VALUE
+no_name_rest(void)
+{
+    ID rest;
+    CONST_ID(rest, "NODE_SPECIAL_NO_NAME_REST");
+    return ID2SYM(rest);
+}
+
+static VALUE
+rest_arg(rb_ast_t *ast, const NODE *rest_arg)
+{
+    return NODE_NAMED_REST_P(rest_arg) ? NEW_CHILD(ast, rest_arg) : no_name_rest();
+}
+
+static VALUE
+node_children(rb_ast_t *ast, const NODE *node)
+{
+    char name[DECIMAL_SIZE_OF_BITS(sizeof(long) * CHAR_BIT) + 2]; /* including '$' */
+
+    enum node_type type = nd_type(node);
+    switch (type) {
+      case NODE_BLOCK:
+        return dump_block(ast, node);
+      case NODE_IF:
+        return rb_ary_new_from_node_args(ast, 3, node->nd_cond, node->nd_body, node->nd_else);
+      case NODE_UNLESS:
+        return rb_ary_new_from_node_args(ast, 3, node->nd_cond, node->nd_body, node->nd_else);
+      case NODE_CASE:
+        return rb_ary_new_from_node_args(ast, 2, node->nd_head, node->nd_body);
+      case NODE_CASE2:
+        return rb_ary_new_from_node_args(ast, 2, node->nd_head, node->nd_body);
+      case NODE_CASE3:
+        return rb_ary_new_from_node_args(ast, 2, node->nd_head, node->nd_body);
+      case NODE_WHEN:
+        return rb_ary_new_from_node_args(ast, 3, node->nd_head, node->nd_body, node->nd_next);
+      case NODE_IN:
+        return rb_ary_new_from_node_args(ast, 3, node->nd_head, node->nd_body, node->nd_next);
+      case NODE_WHILE:
+      case NODE_UNTIL:
+        return rb_ary_push(rb_ary_new_from_node_args(ast, 2, node->nd_cond, node->nd_body),
+                           RBOOL(node->nd_state));
+      case NODE_ITER:
+      case NODE_FOR:
+        return rb_ary_new_from_node_args(ast, 2, node->nd_iter, node->nd_body);
+      case NODE_FOR_MASGN:
+        return rb_ary_new_from_node_args(ast, 1, node->nd_var);
+      case NODE_BREAK:
+      case NODE_NEXT:
+      case NODE_RETURN:
+        return rb_ary_new_from_node_args(ast, 1, node->nd_stts);
+      case NODE_REDO:
+        return rb_ary_new_from_node_args(ast, 0);
+      case NODE_RETRY:
+        return rb_ary_new_from_node_args(ast, 0);
+      case NODE_BEGIN:
+        return rb_ary_new_from_node_args(ast, 1, node->nd_body);
+      case NODE_RESCUE:
+        return rb_ary_new_from_node_args(ast, 3, node->nd_head, node->nd_resq, node->nd_else);
+      case NODE_RESBODY:
+        return rb_ary_new_from_node_args(ast, 3, node->nd_args, node->nd_body, node->nd_head);
+      case NODE_ENSURE:
+        return rb_ary_new_from_node_args(ast, 2, node->nd_head, node->nd_ensr);
+      case NODE_AND:
+      case NODE_OR:
+        {
+            VALUE ary = rb_ary_new();
+
+            while (1) {
+                rb_ary_push(ary, NEW_CHILD(ast, node->nd_1st));
+                if (!node->nd_2nd || !nd_type_p(node->nd_2nd, type))
+                    break;
+                node = node->nd_2nd;
+            }
+            rb_ary_push(ary, NEW_CHILD(ast, node->nd_2nd));
+            return ary;
+        }
+      case NODE_MASGN:
+        if (NODE_NAMED_REST_P(node->nd_args)) {
+            return rb_ary_new_from_node_args(ast, 3, node->nd_value, node->nd_head, node->nd_args);
+        }
+        else {
+            return rb_ary_new_from_args(3, NEW_CHILD(ast, node->nd_value),
+                                        NEW_CHILD(ast, node->nd_head),
+                                        no_name_rest());
+        }
+      case NODE_LASGN:
+      case NODE_DASGN:
+      case NODE_IASGN:
+      case NODE_CVASGN:
+      case NODE_GASGN:
+        if (NODE_REQUIRED_KEYWORD_P(node)) {
+            return rb_ary_new_from_args(2, var_name(node->nd_vid), ID2SYM(rb_intern("NODE_SPECIAL_REQUIRED_KEYWORD")));
+        }
+        return rb_ary_new_from_args(2, var_name(node->nd_vid), NEW_CHILD(ast, node->nd_value));
+      case NODE_CDECL:
+        if (node->nd_vid) {
+            return rb_ary_new_from_args(2, ID2SYM(node->nd_vid), NEW_CHILD(ast, node->nd_value));
+        }
+        return rb_ary_new_from_args(3, NEW_CHILD(ast, node->nd_else), ID2SYM(node->nd_else->nd_mid), NEW_CHILD(ast, node->nd_value));
+      case NODE_OP_ASGN1:
+        return rb_ary_new_from_args(4, NEW_CHILD(ast, node->nd_recv),
+                                    ID2SYM(node->nd_mid),
+                                    NEW_CHILD(ast, node->nd_args->nd_head),
+                                    NEW_CHILD(ast, node->nd_args->nd_body));
+      case NODE_OP_ASGN2:
+        return rb_ary_new_from_args(5, NEW_CHILD(ast, node->nd_recv),
+                                    RBOOL(node->nd_next->nd_aid),
+                                    ID2SYM(node->nd_next->nd_vid),
+                                    ID2SYM(node->nd_next->nd_mid),
+                                    NEW_CHILD(ast, node->nd_value));
+      case NODE_OP_ASGN_AND:
+        return rb_ary_new_from_args(3, NEW_CHILD(ast, node->nd_head), ID2SYM(idANDOP),
+                                    NEW_CHILD(ast, node->nd_value));
+      case NODE_OP_ASGN_OR:
+        return rb_ary_new_from_args(3, NEW_CHILD(ast, node->nd_head), ID2SYM(idOROP),
+                                    NEW_CHILD(ast, node->nd_value));
+      case NODE_OP_CDECL:
+        return rb_ary_new_from_args(3, NEW_CHILD(ast, node->nd_head),
+                                    ID2SYM(node->nd_aid),
+                                    NEW_CHILD(ast, node->nd_value));
+      case NODE_CALL:
+      case NODE_OPCALL:
+      case NODE_QCALL:
+        return rb_ary_new_from_args(3, NEW_CHILD(ast, node->nd_recv),
+                                    ID2SYM(node->nd_mid),
+                                    NEW_CHILD(ast, node->nd_args));
+      case NODE_FCALL:
+        return rb_ary_new_from_args(2, ID2SYM(node->nd_mid),
+                                    NEW_CHILD(ast, node->nd_args));
+      case NODE_VCALL:
+        return rb_ary_new_from_args(1, ID2SYM(node->nd_mid));
+      case NODE_SUPER:
+        return rb_ary_new_from_node_args(ast, 1, node->nd_args);
+      case NODE_ZSUPER:
+        return rb_ary_new_from_node_args(ast, 0);
+      case NODE_LIST:
+      case NODE_VALUES:
+        return dump_array(ast, node);
+      case NODE_ZLIST:
+        return rb_ary_new_from_node_args(ast, 0);
+      case NODE_HASH:
+        return rb_ary_new_from_node_args(ast, 1, node->nd_head);
+      case NODE_YIELD:
+        return rb_ary_new_from_node_args(ast, 1, node->nd_head);
+      case NODE_LVAR:
+      case NODE_DVAR:
+        return rb_ary_new_from_args(1, var_name(node->nd_vid));
+      case NODE_IVAR:
+      case NODE_CONST:
+      case NODE_CVAR:
+      case NODE_GVAR:
+        return rb_ary_new_from_args(1, ID2SYM(node->nd_vid));
+      case NODE_NTH_REF:
+        snprintf(name, sizeof(name), "$%ld", node->nd_nth);
+        return rb_ary_new_from_args(1, ID2SYM(rb_intern(name)));
+      case NODE_BACK_REF:
+        name[0] = '$';
+        name[1] = (char)node->nd_nth;
+        name[2] = '\0';
+        return rb_ary_new_from_args(1, ID2SYM(rb_intern(name)));
+      case NODE_MATCH2:
+        if (node->nd_args) {
+            return rb_ary_new_from_node_args(ast, 3, node->nd_recv, node->nd_value, node->nd_args);
+        }
+        return rb_ary_new_from_node_args(ast, 2, node->nd_recv, node->nd_value);
+      case NODE_MATCH3:
+        return rb_ary_new_from_node_args(ast, 2, node->nd_recv, node->nd_value);
+      case NODE_MATCH:
+      case NODE_LIT:
+      case NODE_STR:
+      case NODE_XSTR:
+        return rb_ary_new_from_args(1, node->nd_lit);
+      case NODE_ONCE:
+        return rb_ary_new_from_node_args(ast, 1, node->nd_body);
+      case NODE_DSTR:
+      case NODE_DXSTR:
+      case NODE_DREGX:
+      case NODE_DSYM:
+        {
+            NODE *n = node->nd_next;
+            VALUE head = Qnil, next = Qnil;
+            if (n) {
+                head = NEW_CHILD(ast, n->nd_head);
+                next = NEW_CHILD(ast, n->nd_next);
+            }
+            return rb_ary_new_from_args(3, node->nd_lit, head, next);
+        }
+      case NODE_EVSTR:
+        return rb_ary_new_from_node_args(ast, 1, node->nd_body);
+      case NODE_ARGSCAT:
+        return rb_ary_new_from_node_args(ast, 2, node->nd_head, node->nd_body);
+      case NODE_ARGSPUSH:
+        return rb_ary_new_from_node_args(ast, 2, node->nd_head, node->nd_body);
+      case NODE_SPLAT:
+        return rb_ary_new_from_node_args(ast, 1, node->nd_head);
+      case NODE_BLOCK_PASS:
+        return rb_ary_new_from_node_args(ast, 2, node->nd_head, node->nd_body);
+      case NODE_DEFN:
+        return rb_ary_new_from_args(2, ID2SYM(node->nd_mid), NEW_CHILD(ast, node->nd_defn));
+      case NODE_DEFS:
+        return rb_ary_new_from_args(3, NEW_CHILD(ast, node->nd_recv), ID2SYM(node->nd_mid), NEW_CHILD(ast, node->nd_defn));
+      case NODE_ALIAS:
+        return rb_ary_new_from_node_args(ast, 2, node->nd_1st, node->nd_2nd);
+      case NODE_VALIAS:
+        return rb_ary_new_from_args(2, ID2SYM(node->nd_alias), ID2SYM(node->nd_orig));
+      case NODE_UNDEF:
+        return rb_ary_new_from_node_args(ast, 1, node->nd_undef);
+      case NODE_CLASS:
+        return rb_ary_new_from_node_args(ast, 3, node->nd_cpath, node->nd_super, node->nd_body);
+      case NODE_MODULE:
+        return rb_ary_new_from_node_args(ast, 2, node->nd_cpath, node->nd_body);
+      case NODE_SCLASS:
+        return rb_ary_new_from_node_args(ast, 2, node->nd_recv, node->nd_body);
+      case NODE_COLON2:
+        return rb_ary_new_from_args(2, NEW_CHILD(ast, node->nd_head), ID2SYM(node->nd_mid));
+      case NODE_COLON3:
+        return rb_ary_new_from_args(1, ID2SYM(node->nd_mid));
+      case NODE_DOT2:
+      case NODE_DOT3:
+      case NODE_FLIP2:
+      case NODE_FLIP3:
+        return rb_ary_new_from_node_args(ast, 2, node->nd_beg, node->nd_end);
+      case NODE_SELF:
+        return rb_ary_new_from_node_args(ast, 0);
+      case NODE_NIL:
+        return rb_ary_new_from_node_args(ast, 0);
+      case NODE_TRUE:
+        return rb_ary_new_from_node_args(ast, 0);
+      case NODE_FALSE:
+        return rb_ary_new_from_node_args(ast, 0);
+      case NODE_ERRINFO:
+        return rb_ary_new_from_node_args(ast, 0);
+      case NODE_DEFINED:
+        return rb_ary_new_from_node_args(ast, 1, node->nd_head);
+      case NODE_POSTEXE:
+        return rb_ary_new_from_node_args(ast, 1, node->nd_body);
+      case NODE_ATTRASGN:
+        return rb_ary_new_from_args(3, NEW_CHILD(ast, node->nd_recv), ID2SYM(node->nd_mid), NEW_CHILD(ast, node->nd_args));
+      case NODE_LAMBDA:
+        return rb_ary_new_from_node_args(ast, 1, node->nd_body);
+      case NODE_OPT_ARG:
+        return rb_ary_new_from_node_args(ast, 2, node->nd_body, node->nd_next);
+      case NODE_KW_ARG:
+        return rb_ary_new_from_node_args(ast, 2, node->nd_body, node->nd_next);
+      case NODE_POSTARG:
+        if (NODE_NAMED_REST_P(node->nd_1st)) {
+            return rb_ary_new_from_node_args(ast, 2, node->nd_1st, node->nd_2nd);
+        }
+        return rb_ary_new_from_args(2, no_name_rest(),
+                                    NEW_CHILD(ast, node->nd_2nd));
+      case NODE_ARGS:
+        {
+            struct rb_args_info *ainfo = node->nd_ainfo;
+            return rb_ary_new_from_args(10,
+                                        INT2NUM(ainfo->pre_args_num),
+                                        NEW_CHILD(ast, ainfo->pre_init),
+                                        NEW_CHILD(ast, ainfo->opt_args),
+                                        var_name(ainfo->first_post_arg),
+                                        INT2NUM(ainfo->post_args_num),
+                                        NEW_CHILD(ast, ainfo->post_init),
+                                        (ainfo->rest_arg == NODE_SPECIAL_EXCESSIVE_COMMA
+                                            ? ID2SYM(rb_intern("NODE_SPECIAL_EXCESSIVE_COMMA"))
+                                            : var_name(ainfo->rest_arg)),
+                                        (ainfo->no_kwarg ? Qfalse : NEW_CHILD(ast, ainfo->kw_args)),
+                                        (ainfo->no_kwarg ? Qfalse : NEW_CHILD(ast, ainfo->kw_rest_arg)),
+                                        var_name(ainfo->block_arg));
+        }
+      case NODE_SCOPE:
+        {
+            rb_ast_id_table_t *tbl = node->nd_tbl;
+            int i, size = tbl ? tbl->size : 0;
+            VALUE locals = rb_ary_new_capa(size);
+            for (i = 0; i < size; i++) {
+                rb_ary_push(locals, var_name(tbl->ids[i]));
+            }
+            return rb_ary_new_from_args(3, locals, NEW_CHILD(ast, node->nd_args), NEW_CHILD(ast, node->nd_body));
+        }
+      case NODE_ARYPTN:
+        {
+            struct rb_ary_pattern_info *apinfo = node->nd_apinfo;
+            VALUE rest = rest_arg(ast, apinfo->rest_arg);
+            return rb_ary_new_from_args(4,
+                                        NEW_CHILD(ast, node->nd_pconst),
+                                        NEW_CHILD(ast, apinfo->pre_args),
+                                        rest,
+                                        NEW_CHILD(ast, apinfo->post_args));
+        }
+      case NODE_FNDPTN:
+        {
+            struct rb_fnd_pattern_info *fpinfo = node->nd_fpinfo;
+            VALUE pre_rest = rest_arg(ast, fpinfo->pre_rest_arg);
+            VALUE post_rest = rest_arg(ast, fpinfo->post_rest_arg);
+            return rb_ary_new_from_args(4,
+                                        NEW_CHILD(ast, node->nd_pconst),
+                                        pre_rest,
+                                        NEW_CHILD(ast, fpinfo->args),
+                                        post_rest);
+        }
+      case NODE_HSHPTN:
+        {
+            VALUE kwrest = node->nd_pkwrestarg == NODE_SPECIAL_NO_REST_KEYWORD ? ID2SYM(rb_intern("NODE_SPECIAL_NO_REST_KEYWORD")) :
+                                                                                 NEW_CHILD(ast, node->nd_pkwrestarg);
+
+            return rb_ary_new_from_args(3,
+                                        NEW_CHILD(ast, node->nd_pconst),
+                                        NEW_CHILD(ast, node->nd_pkwargs),
+                                        kwrest);
+        }
+      case NODE_ERROR:
+        return rb_ary_new_from_node_args(ast, 0);
+      case NODE_ARGS_AUX:
+      case NODE_LAST:
+        break;
+    }
+
+    rb_bug("node_children: unknown node: %s", ruby_node_name(type));
+}
+
+static VALUE
+ast_node_children(rb_execution_context_t *ec, VALUE self)
+{
+    struct ASTNodeData *data;
+    TypedData_Get_Struct(self, struct ASTNodeData, &rb_node_type, data);
+
+    return node_children(data->ast, data->node);
+}
+
+static VALUE
+ast_node_first_lineno(rb_execution_context_t *ec, VALUE self)
+{
+    struct ASTNodeData *data;
+    TypedData_Get_Struct(self, struct ASTNodeData, &rb_node_type, data);
+
+    return INT2NUM(nd_first_lineno(data->node));
+}
+
+static VALUE
+ast_node_first_column(rb_execution_context_t *ec, VALUE self)
+{
+    struct ASTNodeData *data;
+    TypedData_Get_Struct(self, struct ASTNodeData, &rb_node_type, data);
+
+    return INT2NUM(nd_first_column(data->node));
+}
+
+static VALUE
+ast_node_last_lineno(rb_execution_context_t *ec, VALUE self)
+{
+    struct ASTNodeData *data;
+    TypedData_Get_Struct(self, struct ASTNodeData, &rb_node_type, data);
+
+    return INT2NUM(nd_last_lineno(data->node));
+}
+
+static VALUE
+ast_node_last_column(rb_execution_context_t *ec, VALUE self)
+{
+    struct ASTNodeData *data;
+    TypedData_Get_Struct(self, struct ASTNodeData, &rb_node_type, data);
+
+    return INT2NUM(nd_last_column(data->node));
+}
+
+static VALUE
+ast_node_all_tokens(rb_execution_context_t *ec, VALUE self)
+{
+    struct ASTNodeData *data;
+    TypedData_Get_Struct(self, struct ASTNodeData, &rb_node_type, data);
+
+    return rb_ast_tokens(data->ast);
+}
+
+static VALUE
+ast_node_inspect(rb_execution_context_t *ec, VALUE self)
+{
+    VALUE str;
+    VALUE cname;
+    struct ASTNodeData *data;
+    TypedData_Get_Struct(self, struct ASTNodeData, &rb_node_type, data);
+
+    cname = rb_class_path(rb_obj_class(self));
+    str = rb_str_new2("#<");
+
+    rb_str_append(str, cname);
+    rb_str_catf(str, ":%s@%d:%d-%d:%d>",
+                node_type_to_str(data->node),
+                nd_first_lineno(data->node), nd_first_column(data->node),
+                nd_last_lineno(data->node), nd_last_column(data->node));
+
+    return str;
+}
+
+static VALUE
+ast_node_script_lines(rb_execution_context_t *ec, VALUE self)
+{
+    struct ASTNodeData *data;
+    TypedData_Get_Struct(self, struct ASTNodeData, &rb_node_type, data);
+    VALUE ret = data->ast->body.script_lines;
+    if (!RB_TYPE_P(ret, T_ARRAY)) return Qnil;
+    return ret;
+}
+
+#include "ast.rbinc"
+
+void
+Init_ast(void)
+{
+    rb_mAST = rb_define_module_under(rb_cRubyVM, "AbstractSyntaxTree");
+    rb_cNode = rb_define_class_under(rb_mAST, "Node", rb_cObject);
+    rb_undef_alloc_func(rb_cNode);
+}
diff --git a/ast.rb b/ast.rb
new file mode 100644
index 0000000000..f3f72c747f
--- /dev/null
+++ b/ast.rb
@@ -0,0 +1,276 @@
+# for ast.c
+
+# AbstractSyntaxTree provides methods to parse Ruby code into
+# abstract syntax trees. The nodes in the tree
+# are instances of RubyVM::AbstractSyntaxTree::Node.
+#
+# This module is MRI specific as it exposes implementation details
+# of the MRI abstract syntax tree.
+#
+# This module is experimental and its API is not stable, therefore it might
+# change without notice. As examples, the order of children nodes is not
+# guaranteed, the number of children nodes might change, there is no way to
+# access children nodes by name, etc.
+#
+# If you are looking for a stable API or an API working under multiple Ruby
+# implementations, consider using the _parser_ gem or Ripper. If you would
+# like to make RubyVM::AbstractSyntaxTree stable, please join the discussion
+# at https://bugs.ruby-lang.org/issues/14844.
+#
+module RubyVM::AbstractSyntaxTree
+
+  #  call-seq:
+  #     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.
+  #
+  #    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, 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.
+  #
+  #   SyntaxError is raised if _pathname_'s contents are not
+  #   valid Ruby syntax.
+  #
+  #     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, 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_.
+  #
+  #     RubyVM::AbstractSyntaxTree.of(proc {1 + 2})
+  #     # => #<RubyVM::AbstractSyntaxTree::Node:SCOPE@1:35-1:42>
+  #
+  #     def hello
+  #       puts "hello, world"
+  #     end
+  #
+  #     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
+
+  #  call-seq:
+  #     RubyVM::AbstractSyntaxTree.node_id_for_backtrace_location(backtrace_location)   -> integer
+  #
+  #   Returns the node id for the given backtrace location.
+  #
+  #     begin
+  #       raise
+  #     rescue =>  e
+  #       loc = e.backtrace_locations.first
+  #       RubyVM::AbstractSyntaxTree.node_id_for_backtrace_location(loc)
+  #     end # => 0
+  def self.node_id_for_backtrace_location backtrace_location
+    Primitive.node_id_for_backtrace_location backtrace_location
+  end
+
+  # RubyVM::AbstractSyntaxTree::Node instances are created by parse methods in
+  # RubyVM::AbstractSyntaxTree.
+  #
+  # This class is MRI specific.
+  #
+  class Node
+
+    #  call-seq:
+    #     node.type -> symbol
+    #
+    #  Returns the type of this node as a symbol.
+    #
+    #    root = RubyVM::AbstractSyntaxTree.parse("x = 1 + 2")
+    #    root.type # => :SCOPE
+    #    lasgn = root.children[2]
+    #    lasgn.type # => :LASGN
+    #    call = lasgn.children[1]
+    #    call.type # => :OPCALL
+    def type
+      Primitive.ast_node_type
+    end
+
+    #  call-seq:
+    #     node.first_lineno -> integer
+    #
+    #  The line number in the source code where this AST's text began.
+    def first_lineno
+      Primitive.ast_node_first_lineno
+    end
+
+    #  call-seq:
+    #     node.first_column -> integer
+    #
+    #  The column number in the source code where this AST's text began.
+    def first_column
+      Primitive.ast_node_first_column
+    end
+
+    #  call-seq:
+    #     node.last_lineno -> integer
+    #
+    #  The line number in the source code where this AST's text ended.
+    def last_lineno
+      Primitive.ast_node_last_lineno
+    end
+
+    #  call-seq:
+    #     node.last_column -> integer
+    #
+    #  The column number in the source code where this AST's text ended.
+    def last_column
+      Primitive.ast_node_last_column
+    end
+
+    #  call-seq:
+    #     node.tokens -> array
+    #
+    #  Returns tokens corresponding to the location of the node.
+    #  Returns +nil+ if +keep_tokens+ is not enabled when #parse method is called.
+    #
+    #    root = RubyVM::AbstractSyntaxTree.parse("x = 1 + 2", keep_tokens: true)
+    #    root.tokens # => [[0, :tIDENTIFIER, "x", [1, 0, 1, 1]], [1, :tSP, " ", [1, 1, 1, 2]], ...]
+    #    root.tokens.map{_1[2]}.join # => "x = 1 + 2"
+    #
+    #  Token is an array of:
+    #
+    #  - id
+    #  - token type
+    #  - source code text
+    #  - location [ first_lineno, first_column, last_lineno, last_column ]
+    def tokens
+      return nil unless all_tokens
+
+      all_tokens.each_with_object([]) do |token, a|
+        loc = token.last
+        if ([first_lineno, first_column] <=> [loc[0], loc[1]]) <= 0 &&
+           ([last_lineno, last_column]   <=> [loc[2], loc[3]]) >= 0
+           a << token
+        end
+      end
+    end
+
+    #  call-seq:
+    #     node.all_tokens -> array
+    #
+    #  Returns all tokens for the input script regardless the receiver node.
+    #  Returns +nil+ if +keep_tokens+ is not enabled when #parse method is called.
+    #
+    #    root = RubyVM::AbstractSyntaxTree.parse("x = 1 + 2", keep_tokens: true)
+    #    root.all_tokens # => [[0, :tIDENTIFIER, "x", [1, 0, 1, 1]], [1, :tSP, " ", [1, 1, 1, 2]], ...]
+    #    root.children[-1].all_tokens # => [[0, :tIDENTIFIER, "x", [1, 0, 1, 1]], [1, :tSP, " ", [1, 1, 1, 2]], ...]
+    def all_tokens
+      Primitive.ast_node_all_tokens
+    end
+
+    #  call-seq:
+    #     node.children -> array
+    #
+    #  Returns AST nodes under this one.  Each kind of node
+    #  has different children, depending on what kind of node it is.
+    #
+    #  The returned array may contain other nodes or <code>nil</code>.
+    def children
+      Primitive.ast_node_children
+    end
+
+    #  call-seq:
+    #     node.inspect -> string
+    #
+    #  Returns debugging information about this node as a string.
+    def inspect
+      Primitive.ast_node_inspect
+    end
+
+    #  call-seq:
+    #     node.node_id -> integer
+    #
+    #  Returns an internal node_id number.
+    #  Note that this is an API for ruby internal use, debugging,
+    #  and research. Do not use this for any other purpose.
+    #  The compatibility is not guaranteed.
+    def node_id
+      Primitive.ast_node_node_id
+    end
+
+    #  call-seq:
+    #     node.script_lines -> array
+    #
+    #  Returns the original source code as an array of lines.
+    #
+    #  Note that this is an API for ruby internal use, debugging,
+    #  and research. Do not use this for any other purpose.
+    #  The compatibility is not guaranteed.
+    def script_lines
+      Primitive.ast_node_script_lines
+    end
+
+    #  call-seq:
+    #     node.source -> string
+    #
+    #  Returns the code fragment that corresponds to this AST.
+    #
+    #  Note that this is an API for ruby internal use, debugging,
+    #  and research. Do not use this for any other purpose.
+    #  The compatibility is not guaranteed.
+    #
+    #  Also note that this API may return an incomplete code fragment
+    #  that does not parse; for example, a here document following
+    #  an expression may be dropped.
+    def source
+      lines = script_lines
+      if lines
+        lines = lines[first_lineno - 1 .. last_lineno - 1]
+        lines[-1] = lines[-1][0...last_column]
+        lines[0] = lines[0][first_column..-1]
+        lines.join
+      else
+        nil
+      end
+    end
+  end
+end
diff --git a/autogen.sh b/autogen.sh
new file mode 100755
index 0000000000..f8cdf3c0c1
--- /dev/null
+++ b/autogen.sh
@@ -0,0 +1,17 @@
+#!/bin/sh
+
+PWD=
+case "$0" in
+*/*) srcdir=`dirname $0`;;
+*) srcdir="";;
+esac
+
+symlink='--install --symlink'
+case " $* " in
+    *" -i "*|*" --install "*)
+        # reset to copy missing standard auxiliary files, instead of symlinks
+        symlink=
+        ;;
+esac
+
+exec ${AUTORECONF:-autoreconf} ${symlink} "$@" ${srcdir:+"$srcdir"}
diff --git a/basictest/runner.rb b/basictest/runner.rb
index 3a60036ffa..0f398e7acc 100755
--- a/basictest/runner.rb
+++ b/basictest/runner.rb
@@ -17,6 +17,9 @@ $stderr.reopen($stdout)
 error = ''
 
 srcdir = File.expand_path('..', File.dirname(__FILE__))
+if env = ENV["RUBYOPT"]
+  ENV["RUBYOPT"] = env + " -W1"
+end
 `#{ruby} #{opt} -W1 #{srcdir}/basictest/test.rb #{ARGV.join(' ')}`.each_line do |line|
   if line =~ /^end of test/
     print "\ntest succeeded\n"
diff --git a/basictest/test.rb b/basictest/test.rb
index 0ba4503faa..95875b52a6 100644..100755
--- a/basictest/test.rb
+++ b/basictest/test.rb
@@ -35,7 +35,7 @@ class Progress
       # dircolors-like style
       colors = (colors = ENV['TEST_COLORS']) ? Hash[colors.scan(/(\w+)=([^:\n]*)/)] : {}
       begin
-        File.read(File.join(__dir__, "../test/colors")).scan(/(\w+)=([^:\n]*)/) do |n, c|
+        File.read(File.join(__dir__, "../tool/colors")).scan(/(\w+)=([^:\n]*)/) do |n, c|
           colors[n] ||= c
         end
       rescue
@@ -984,13 +984,6 @@ test_ok($z == 0)
 
 test_check "iterator"
 
-test_ok(!iterator?)
-
-def ttt
-  test_ok(iterator?)
-end
-ttt{}
-
 # yield at top level
 test_ok(!defined?(yield))
 
@@ -1432,9 +1425,6 @@ marity_test(:test_ok)
 marity_test(:marity_test)
 marity_test(:p)
 
-lambda(&method(:test_ok)).call(true)
-lambda(&block_get{|a,n| test_ok(a,n)}).call(true, 2)
-
 class ITER_TEST1
    def a
      block_given?
@@ -1739,7 +1729,7 @@ a = nil
 test_ok(defined?(a))
 test_ok(a == nil)
 
-# multiple asignment
+# multiple assignment
 a, b = 1, 2
 test_ok(a == 1 && b == 2)
 
@@ -1860,11 +1850,9 @@ $bad=false
 eval 'while false; $bad = true; print "foo\n" end'
 test_ok(!$bad)
 
-test_ok(eval('TRUE'))
+test_ok(eval('Object'))
 test_ok(eval('true'))
-test_ok(!eval('NIL'))
 test_ok(!eval('nil'))
-test_ok(!eval('FALSE'))
 test_ok(!eval('false'))
 
 $foo = 'test_ok(true)'
@@ -1972,6 +1960,8 @@ test_ok(p1.call == 5)
 test_ok(i7 == nil)
 end
 
+# WASI doesn't support spawning a new process for now.
+unless /wasi/ =~ RUBY_PLATFORM
 test_check "system"
 test_ok(`echo foobar` == "foobar\n")
 test_ok(`./miniruby -e 'print "foobar"'` == 'foobar')
@@ -2022,6 +2012,7 @@ test_ok(done)
 
 File.unlink script_tmp or `/bin/rm -f "#{script_tmp}"`
 File.unlink "#{script_tmp}.bak" or `/bin/rm -f "#{script_tmp}.bak"`
+end # not /wasi/ =~ RUBY_PLATFORM
 
 test_check "const"
 TEST1 = 1
@@ -2149,7 +2140,7 @@ $_ = foobar
 test_ok($_ == foobar)
 
 class Gods
-  @@rule = "Uranus"		# private to Gods
+  @@rule = "Uranus"
   def ruler0
     @@rule
   end
@@ -2172,7 +2163,7 @@ module Olympians
 end
 
 class Titans < Gods
-  @@rule = "Cronus"		# do not affect @@rule in Gods
+  @@rule = "Cronus"		# modifies @@rule in Gods
   include Olympians
   def ruler4
     @@rule
@@ -2187,7 +2178,14 @@ test_ok(Titans.ruler2 == "Cronus")
 atlas = Titans.new
 test_ok(atlas.ruler0 == "Cronus")
 test_ok(atlas.ruler3 == "Zeus")
-test_ok(atlas.ruler4 == "Cronus")
+begin
+  atlas.ruler4
+rescue RuntimeError => e
+  test_ok(e.message.include?("class variable @@rule of Olympians is overtaken by Gods"))
+else
+  test_ok(false)
+end
+test_ok(atlas.ruler3 == "Zeus")
 
 test_check "trace"
 $x = 1234
@@ -2244,11 +2242,11 @@ test_check "alias"
 class Alias0
   def foo; "foo" end
 end
-class Alias1<Alias0
+class Alias1 < Alias0
   alias bar foo
   def foo; "foo+" + super end
 end
-class Alias2<Alias1
+class Alias2 < Alias1
   alias baz foo
   undef foo
 end
@@ -2260,7 +2258,7 @@ test_ok(x.baz == "foo+foo")
 # test_check for cache
 test_ok(x.baz == "foo+foo")
 
-class Alias3<Alias2
+class Alias3 < Alias2
   def foo
     defined? super
   end
diff --git a/benchmark/README.md b/benchmark/README.md
new file mode 100644
index 0000000000..e11381cad9
--- /dev/null
+++ b/benchmark/README.md
@@ -0,0 +1,74 @@
+# ruby/benchmark
+
+This directory has benchmark definitions to be run with
+[benchmark\_driver.gem](https://github.com/benchmark-driver/benchmark-driver).
+
+## Normal usage
+
+Execute `gem install benchmark_driver` and run a command like:
+
+```bash
+# Run a benchmark script with the ruby in the $PATH
+benchmark-driver benchmark/app_fib.rb
+
+# Run benchmark scripts with multiple Ruby executables or options
+benchmark-driver benchmark/*.rb -e /path/to/ruby -e '/path/to/ruby --jit'
+
+# Or compare Ruby versions managed by rbenv
+benchmark-driver benchmark/*.rb --rbenv '2.5.1;2.6.0-preview2 --jit'
+
+# You can collect many metrics in many ways
+benchmark-driver benchmark/*.rb --runner memory --output markdown
+
+# Some are defined with YAML for complex setup or accurate measurement
+benchmark-driver benchmark/*.yml
+```
+
+See also:
+
+```console
+Usage: benchmark-driver [options] RUBY|YAML...
+    -r, --runner TYPE                Specify runner type: ips, time, memory, once, block (default: ips)
+    -o, --output TYPE                Specify output type: compare, simple, markdown, record, all (default: compare)
+    -e, --executables EXECS          Ruby executables (e1::path1 arg1; e2::path2 arg2;...)
+        --rbenv VERSIONS             Ruby executables in rbenv (x.x.x arg1;y.y.y arg2;...)
+        --repeat-count NUM           Try benchmark NUM times and use the fastest result or the worst memory usage
+        --repeat-result TYPE         Yield "best", "average" or "worst" result with --repeat-count (default: best)
+        --alternate                  Alternate executables instead of running the same executable in a row with --repeat-count
+        --bundler                    Install and use gems specified in Gemfile
+        --filter REGEXP              Filter out benchmarks with given regexp
+        --run-duration SECONDS       Warmup estimates loop_count to run for this duration (default: 3)
+        --timeout SECONDS            Timeout ruby command execution with timeout(1)
+    -v, --verbose                    Verbose mode. Multiple -v options increase visilibity (max: 2)
+```
+
+## make benchmark
+
+Using `make benchmark`, `make update-benchmark-driver` automatically downloads
+the supported version of benchmark\_driver, and it runs benchmarks with the downloaded
+benchmark\_driver.
+
+```bash
+# Run all benchmarks with the ruby in the $PATH and the built ruby
+make benchmark
+
+# Or compare with specific ruby binary
+make benchmark COMPARE_RUBY="/path/to/ruby --jit"
+
+# Run vm benchmarks
+make benchmark ITEM=vm
+
+# Run some limited benchmarks in ITEM-matched files
+make benchmark ITEM=vm OPTS=--filter=block
+
+# You can specify the benchmark by an exact filename instead of using the default argument:
+# ARGS = $$(find $(srcdir)/benchmark -maxdepth 1 -name '*$(ITEM)*.yml' -o -name '*$(ITEM)*.rb')
+make benchmark ARGS=benchmark/erb_render.yml
+
+# You can specify any option via $OPTS
+make benchmark OPTS="--help"
+
+# With `make benchmark`, some special runner plugins are available:
+#   -r peak, -r size, -r total, -r utime, -r stime, -r cutime, -r cstime
+make benchmark ITEM=vm_bigarray OPTS="-r peak"
+```
diff --git a/benchmark/bm_app_answer.rb b/benchmark/app_answer.rb
index 3cd8a8fd37..3cd8a8fd37 100644
--- a/benchmark/bm_app_answer.rb
+++ b/benchmark/app_answer.rb
diff --git a/benchmark/app_aobench.rb b/benchmark/app_aobench.rb
new file mode 100644
index 0000000000..16296af12b
--- /dev/null
+++ b/benchmark/app_aobench.rb
@@ -0,0 +1,297 @@
+# coding: US-ASCII
+
+# AO render benchmark
+# Original program (C) Syoyo Fujita in Javascript (and other languages)
+#      https://code.google.com/p/aobench/
+# Ruby(yarv2llvm) version by Hideki Miura
+#
+
+IMAGE_WIDTH = 256
+IMAGE_HEIGHT = 256
+NSUBSAMPLES = 2
+NAO_SAMPLES = 8
+
+srand(0)
+
+class Vec
+  def initialize(x, y, z)
+    @x = x
+    @y = y
+    @z = z
+  end
+
+  attr_accessor :x, :y, :z
+
+  def vadd(b)
+    Vec.new(@x + b.x, @y + b.y, @z + b.z)
+  end
+
+  def vsub(b)
+    Vec.new(@x - b.x, @y - b.y, @z - b.z)
+  end
+
+  def vcross(b)
+    Vec.new(@y * b.z - @z * b.y,
+            @z * b.x - @x * b.z,
+            @x * b.y - @y * b.x)
+  end
+
+  def vdot(b)
+    @x * b.x + @y * b.y + @z * b.z
+  end
+
+  def vlength
+    Math.sqrt(@x * @x + @y * @y + @z * @z)
+  end
+
+  def vnormalize
+    len = vlength
+    v = Vec.new(@x, @y, @z)
+    if len > 1.0e-17 then
+      v.x = v.x / len
+      v.y = v.y / len
+      v.z = v.z / len
+    end
+    v
+  end
+end
+
+
+class Sphere
+  def initialize(center, radius)
+    @center = center
+    @radius = radius
+  end
+
+  attr_reader :center, :radius
+
+  def intersect(ray, isect)
+    rs = ray.org.vsub(@center)
+    b = rs.vdot(ray.dir)
+    c = rs.vdot(rs) - (@radius * @radius)
+    d = b * b - c
+    if d > 0.0 then
+      t = - b - Math.sqrt(d)
+
+      if t > 0.0 and t < isect.t then
+        isect.t = t
+        isect.hit = true
+        isect.pl = Vec.new(ray.org.x + ray.dir.x * t,
+                          ray.org.y + ray.dir.y * t,
+                          ray.org.z + ray.dir.z * t)
+        n = isect.pl.vsub(@center)
+        isect.n = n.vnormalize
+      else
+        0.0
+      end
+    end
+    nil
+  end
+end
+
+class Plane
+  def initialize(p, n)
+    @p = p
+    @n = n
+  end
+
+  def intersect(ray, isect)
+    d = -@p.vdot(@n)
+    v = ray.dir.vdot(@n)
+    v0 = v
+    if v < 0.0 then
+      v0 = -v
+    end
+    if v0 < 1.0e-17 then
+      return
+    end
+
+    t = -(ray.org.vdot(@n) + d) / v
+
+    if t > 0.0 and t < isect.t then
+      isect.hit = true
+      isect.t = t
+      isect.n = @n
+      isect.pl = Vec.new(ray.org.x + t * ray.dir.x,
+                        ray.org.y + t * ray.dir.y,
+                        ray.org.z + t * ray.dir.z)
+    end
+    nil
+  end
+end
+
+class Ray
+  def initialize(org, dir)
+    @org = org
+    @dir = dir
+  end
+
+  attr_accessor :org, :dir
+end
+
+class Isect
+  def initialize
+    @t = 10000000.0
+    @hit = false
+    @pl = Vec.new(0.0, 0.0, 0.0)
+    @n = Vec.new(0.0, 0.0, 0.0)
+  end
+
+  attr_accessor :t, :hit, :pl, :n
+end
+
+def clamp(f)
+  i = f * 255.5
+  if i > 255.0 then
+    i = 255.0
+  end
+  if i < 0.0 then
+    i = 0.0
+  end
+  i.to_i
+end
+
+def otherBasis(basis, n)
+  basis[2] = Vec.new(n.x, n.y, n.z)
+  basis[1] = Vec.new(0.0, 0.0, 0.0)
+
+  if n.x < 0.6 and n.x > -0.6 then
+    basis[1].x = 1.0
+  elsif n.y < 0.6 and n.y > -0.6 then
+    basis[1].y = 1.0
+  elsif n.z < 0.6 and n.z > -0.6 then
+    basis[1].z = 1.0
+  else
+    basis[1].x = 1.0
+  end
+
+  basis[0] = basis[1].vcross(basis[2])
+  basis[0] = basis[0].vnormalize
+
+  basis[1] = basis[2].vcross(basis[0])
+  basis[1] = basis[1].vnormalize
+end
+
+class Scene
+  def initialize
+    @spheres = Array.new
+    @spheres[0] = Sphere.new(Vec.new(-2.0, 0.0, -3.5), 0.5)
+    @spheres[1] = Sphere.new(Vec.new(-0.5, 0.0, -3.0), 0.5)
+    @spheres[2] = Sphere.new(Vec.new(1.0, 0.0, -2.2), 0.5)
+    @plane = Plane.new(Vec.new(0.0, -0.5, 0.0), Vec.new(0.0, 1.0, 0.0))
+  end
+
+  def ambient_occlusion(isect)
+    basis = Array.new
+    otherBasis(basis, isect.n)
+
+    ntheta    = NAO_SAMPLES
+    nphi      = NAO_SAMPLES
+    eps       = 0.0001
+    occlusion = 0.0
+
+    p0 = Vec.new(isect.pl.x + eps * isect.n.x,
+                isect.pl.y + eps * isect.n.y,
+                isect.pl.z + eps * isect.n.z)
+    nphi.times do |j|
+      ntheta.times do |i|
+        r = rand
+        phi = 2.0 * 3.14159265 * rand
+        x = Math.cos(phi) * Math.sqrt(1.0 - r)
+        y = Math.sin(phi) * Math.sqrt(1.0 - r)
+        z = Math.sqrt(r)
+
+        rx = x * basis[0].x + y * basis[1].x + z * basis[2].x
+        ry = x * basis[0].y + y * basis[1].y + z * basis[2].y
+        rz = x * basis[0].z + y * basis[1].z + z * basis[2].z
+
+        raydir = Vec.new(rx, ry, rz)
+        ray = Ray.new(p0, raydir)
+
+        occisect = Isect.new
+        @spheres[0].intersect(ray, occisect)
+        @spheres[1].intersect(ray, occisect)
+        @spheres[2].intersect(ray, occisect)
+        @plane.intersect(ray, occisect)
+        if occisect.hit then
+          occlusion = occlusion + 1.0
+        else
+          0.0
+        end
+      end
+    end
+
+    occlusion = (ntheta.to_f * nphi.to_f - occlusion) / (ntheta.to_f * nphi.to_f)
+
+    Vec.new(occlusion, occlusion, occlusion)
+  end
+
+  def render(w, h, nsubsamples)
+    cnt = 0
+    nsf = nsubsamples.to_f
+    h.times do |y|
+      w.times do |x|
+        rad = Vec.new(0.0, 0.0, 0.0)
+
+        # Subsampling
+        nsubsamples.times do |v|
+          nsubsamples.times do |u|
+
+            cnt = cnt + 1
+            wf = w.to_f
+            hf = h.to_f
+            xf = x.to_f
+            yf = y.to_f
+            uf = u.to_f
+            vf = v.to_f
+
+            px = (xf + (uf / nsf) - (wf / 2.0)) / (wf / 2.0)
+            py = -(yf + (vf / nsf) - (hf / 2.0)) / (hf / 2.0)
+
+            eye = Vec.new(px, py, -1.0).vnormalize
+
+            ray = Ray.new(Vec.new(0.0, 0.0, 0.0), eye)
+
+            isect = Isect.new
+            @spheres[0].intersect(ray, isect)
+            @spheres[1].intersect(ray, isect)
+            @spheres[2].intersect(ray, isect)
+            @plane.intersect(ray, isect)
+            if isect.hit then
+              col = ambient_occlusion(isect)
+              rad.x = rad.x + col.x
+              rad.y = rad.y + col.y
+              rad.z = rad.z + col.z
+            end
+          end
+        end
+
+        r = rad.x / (nsf * nsf)
+        g = rad.y / (nsf * nsf)
+        b = rad.z / (nsf * nsf)
+        printf("%c", clamp(r))
+        printf("%c", clamp(g))
+        printf("%c", clamp(b))
+      end
+      nil
+    end
+
+    nil
+  end
+end
+
+alias printf_orig printf
+def printf *args
+  # $fp.printf(*args)
+end
+
+# File.open("ao.ppm", "w") do |fp|
+  # $fp = fp
+  printf("P6\n")
+  printf("%d %d\n", IMAGE_WIDTH, IMAGE_HEIGHT)
+  printf("255\n")
+  Scene.new.render(IMAGE_WIDTH, IMAGE_HEIGHT, NSUBSAMPLES)
+# end
+
+undef printf
+alias printf printf_orig
diff --git a/benchmark/app_erb.yml b/benchmark/app_erb.yml
new file mode 100644
index 0000000000..31e29b7644
--- /dev/null
+++ b/benchmark/app_erb.yml
@@ -0,0 +1,23 @@
+#
+# Create many HTML strings with ERB.
+#
+prelude: |
+  require 'erb'
+
+  data = <<erb
+  <html>
+    <head> <%= title %> </head>
+    <body>
+      <h1> <%= title %> </h1>
+      <p>
+        <%= content %>
+      </p>
+    </body>
+  </html>
+  erb
+
+  title = "hello world!"
+  content = "hello world!\n" * 10
+benchmark:
+  app_erb: ERB.new(data).result(binding)
+loop_count: 15000
diff --git a/benchmark/bm_app_factorial.rb b/benchmark/app_factorial.rb
index 45f471dfdb..45f471dfdb 100644
--- a/benchmark/bm_app_factorial.rb
+++ b/benchmark/app_factorial.rb
diff --git a/benchmark/bm_app_fib.rb b/benchmark/app_fib.rb
index 34a7b2e725..34a7b2e725 100644
--- a/benchmark/bm_app_fib.rb
+++ b/benchmark/app_fib.rb
diff --git a/benchmark/bm_app_lc_fizzbuzz.rb b/benchmark/app_lc_fizzbuzz.rb
index f09574bbeb..f09574bbeb 100644
--- a/benchmark/bm_app_lc_fizzbuzz.rb
+++ b/benchmark/app_lc_fizzbuzz.rb
diff --git a/benchmark/bm_app_mandelbrot.rb b/benchmark/app_mandelbrot.rb
index 801b75e8e2..801b75e8e2 100644
--- a/benchmark/bm_app_mandelbrot.rb
+++ b/benchmark/app_mandelbrot.rb
diff --git a/benchmark/app_pentomino.rb b/benchmark/app_pentomino.rb
new file mode 100644
index 0000000000..47be7b203f
--- /dev/null
+++ b/benchmark/app_pentomino.rb
@@ -0,0 +1,130 @@
+#!/usr/local/bin/ruby
+# This program is contributed by Shin Nishiyama
+
+
+# modified by K.Sasada
+
+NP = 5
+ROW = 8 + NP
+COL = 8
+
+$p = []
+$b = []
+$no = 0
+
+def piece(n, a, nb)
+  nb.each{|x|
+    a[n] = x
+    if n == NP-1
+      $p << [a.sort]
+    else
+      nbc=nb.dup
+      [-ROW, -1, 1, ROW].each{|d|
+        if x+d > 0 and not a.include?(x+d) and not nbc.include?(x+d)
+          nbc << x+d
+        end
+      }
+      nbc.delete x
+      piece(n+1,a[0..n],nbc)
+    end
+  }
+end
+
+def kikaku(a)
+  a.collect {|x| x - a[0]}
+end
+def ud(a)
+  kikaku(a.collect {|x| ((x+NP)%ROW)-ROW*((x+NP)/ROW) }.sort)
+end
+def rl(a)
+  kikaku(a.collect {|x| ROW*((x+NP)/ROW)+ROW-((x+NP)%ROW)}.sort)
+end
+def xy(a)
+  kikaku(a.collect {|x| ROW*((x+NP)%ROW) + (x+NP)/ROW }.sort)
+end
+
+def mkpieces
+  piece(0,[],[0])
+  $p.each do |a|
+    a0 = a[0]
+    a[1] = ud(a0)
+    a[2] = rl(a0)
+    a[3] = ud(rl(a0))
+    a[4] = xy(a0)
+    a[5] = ud(xy(a0))
+    a[6] = rl(xy(a0))
+    a[7] = ud(rl(xy(a0)))
+    a.sort!
+    a.uniq!
+  end
+  $p.uniq!.sort! {|x,y| x[0] <=> y[0] }
+end
+
+def mkboard
+  (0...ROW*COL).each{|i|
+    if i % ROW >= ROW-NP
+      $b[i] = -2
+    else
+      $b[i] = -1
+    end
+    $b[3*ROW+3]=$b[3*ROW+4]=$b[4*ROW+3]=$b[4*ROW+4]=-2
+  }
+end
+
+def pboard
+  return # skip print
+  print "No. #$no\n"
+  (0...COL).each{|i|
+    print "|"
+    (0...ROW-NP).each{|j|
+      x = $b[i*ROW+j]
+      if x < 0
+        print "..|"
+      else
+        printf "%2d|",x+1
+      end
+    }
+    print "\n"
+  }
+  print "\n"
+end
+
+$pnum=[]
+def setpiece(a,pos)
+  if a.length == $p.length then
+    $no += 1
+    pboard
+    return
+  end
+  while $b[pos] != -1
+    pos += 1
+  end
+  ($pnum - a).each do |i|
+    $p[i].each do |x|
+      f = 0
+      x.each{|s|
+        if $b[pos+s] != -1
+          f=1
+          break
+        end
+      }
+      if f == 0 then
+        x.each{|s|
+          $b[pos+s] = i
+        }
+        a << i
+        setpiece(a.dup, pos)
+        a.pop
+        x.each{|s|
+          $b[pos+s] = -1
+        }
+      end
+    end
+  end
+end
+
+mkpieces
+mkboard
+$p[4] = [$p[4][0]]
+$pnum = (0...$p.length).to_a
+setpiece([],0)
diff --git a/benchmark/bm_app_raise.rb b/benchmark/app_raise.rb
index 5db8f95d50..5db8f95d50 100644
--- a/benchmark/bm_app_raise.rb
+++ b/benchmark/app_raise.rb
diff --git a/benchmark/bm_app_strconcat.rb b/benchmark/app_strconcat.rb
index 7eed7c1aed..7eed7c1aed 100644
--- a/benchmark/bm_app_strconcat.rb
+++ b/benchmark/app_strconcat.rb
diff --git a/benchmark/bm_app_tak.rb b/benchmark/app_tak.rb
index efe5380f4e..efe5380f4e 100644
--- a/benchmark/bm_app_tak.rb
+++ b/benchmark/app_tak.rb
diff --git a/benchmark/bm_app_tarai.rb b/benchmark/app_tarai.rb
index 4c146f5ccf..4c146f5ccf 100644
--- a/benchmark/bm_app_tarai.rb
+++ b/benchmark/app_tarai.rb
diff --git a/benchmark/bm_app_uri.rb b/benchmark/app_uri.rb
index 586edfd5dc..586edfd5dc 100644
--- a/benchmark/bm_app_uri.rb
+++ b/benchmark/app_uri.rb
diff --git a/benchmark/array_flatten.yml b/benchmark/array_flatten.yml
new file mode 100644
index 0000000000..88ef544ba0
--- /dev/null
+++ b/benchmark/array_flatten.yml
@@ -0,0 +1,19 @@
+prelude: |
+  small_flat_ary = 5.times.to_a
+  large_flat_ary = 100.times.to_a
+  small_pairs_ary = [[1, 2]] * 5
+  large_pairs_ary = [[1, 2]] * 100
+  mostly_flat_ary = 100.times.to_a.push([101, 102])
+
+benchmark:
+  small_flat_ary.flatten: small_flat_ary.flatten
+  small_flat_ary.flatten!: small_flat_ary.flatten!
+  large_flat_ary.flatten: large_flat_ary.flatten
+  large_flat_ary.flatten!: large_flat_ary.flatten!
+  small_pairs_ary.flatten: small_pairs_ary.flatten
+  small_pairs_ary.flatten!: small_pairs_ary.dup.flatten!
+  large_pairs_ary.flatten: large_pairs_ary.flatten
+  large_pairs_ary.flatten!: large_pairs_ary.dup.flatten!
+  mostly_flat_ary.flatten: mostly_flat_ary.flatten
+  mostly_flat_ary.flatten!: mostly_flat_ary.dup.flatten!
+loop_count: 10000
diff --git a/benchmark/array_intersection.yml b/benchmark/array_intersection.yml
new file mode 100644
index 0000000000..26705323fd
--- /dev/null
+++ b/benchmark/array_intersection.yml
@@ -0,0 +1,14 @@
+prelude: |
+  small1 = [1, 2, 3]
+  small2 = [1, 2, 3, 4, 5]
+  small3 = [2, 3, 4, 5]
+  small4 = [2]
+  big1 = [1, 2, 3, 4] * 64
+  big2 = [1, 2, 3] * 64
+  big3 = [1, 2] * 64
+
+benchmark:
+  small-&: small1 & small2 & small3 & small4
+  small-intersection: small1.intersection(small2, small3, small4)
+  big-&: big1 & big2 & big3
+  big-intersection: big1.intersection(big2, big3)
diff --git a/benchmark/array_max_float.yml b/benchmark/array_max_float.yml
new file mode 100644
index 0000000000..ace1ae2e14
--- /dev/null
+++ b/benchmark/array_max_float.yml
@@ -0,0 +1,30 @@
+prelude: |
+  ary2 = 2.times.map(&:to_f).shuffle
+  ary10 = 10.times.map(&:to_f).shuffle
+  ary100 = 100.times.map(&:to_f).shuffle
+  ary500 = 500.times.map(&:to_f).shuffle
+  ary1000 = 1000.times.map(&:to_f).shuffle
+  ary2000 = 2500.times.map(&:to_f).shuffle
+  ary3000 = 2500.times.map(&:to_f).shuffle
+  ary5000 = 5000.times.map(&:to_f).shuffle
+  ary10000 = 10000.times.map(&:to_f).shuffle
+  ary20000 = 20000.times.map(&:to_f).shuffle
+  ary50000 = 50000.times.map(&:to_f).shuffle
+  ary100000 = 100000.times.map(&:to_f).shuffle
+
+benchmark:
+  ary2.max: ary2.max
+  ary10.max: ary10.max
+  ary100.max: ary100.max
+  ary500.max: ary500.max
+  ary1000.max: ary1000.max
+  ary2000.max: ary2000.max
+  ary3000.max: ary3000.max
+  ary5000.max: ary5000.max
+  ary10000.max: ary10000.max
+  ary20000.max: ary20000.max
+  ary50000.max: ary50000.max
+  ary100000.max: ary100000.max
+
+loop_count: 10000
+
diff --git a/benchmark/array_max_int.yml b/benchmark/array_max_int.yml
new file mode 100644
index 0000000000..acd83684d0
--- /dev/null
+++ b/benchmark/array_max_int.yml
@@ -0,0 +1,31 @@
+prelude: |
+  ary2 = 2.times.to_a.shuffle
+  ary10 = 10.times.to_a.shuffle
+  ary100 = 100.times.to_a.shuffle
+  ary500 = 500.times.to_a.shuffle
+  ary1000 = 1000.times.to_a.shuffle
+  ary2000 = 2500.times.to_a.shuffle
+  ary3000 = 2500.times.to_a.shuffle
+  ary5000 = 5000.times.to_a.shuffle
+  ary10000 = 10000.times.to_a.shuffle
+  ary20000 = 20000.times.to_a.shuffle
+  ary50000 = 50000.times.to_a.shuffle
+  ary100000 = 100000.times.to_a.shuffle
+  ary1000000 = 1000000.times.to_a.shuffle
+
+benchmark:
+  ary2.max: ary2.max
+  ary10.max: ary10.max
+  ary100.max: ary100.max
+  ary500.max: ary500.max
+  ary1000.max: ary1000.max
+  ary2000.max: ary2000.max
+  ary3000.max: ary3000.max
+  ary5000.max: ary5000.max
+  ary10000.max: ary10000.max
+  ary20000.max: ary20000.max
+  ary50000.max: ary50000.max
+  ary100000.max: ary100000.max
+  ary1000000.max: ary1000000.max
+
+loop_count: 10000
diff --git a/benchmark/array_max_str.yml b/benchmark/array_max_str.yml
new file mode 100644
index 0000000000..2aeed010f2
--- /dev/null
+++ b/benchmark/array_max_str.yml
@@ -0,0 +1,30 @@
+prelude: |
+  ary2 = 2.times.map(&:to_s).shuffle
+  ary10 = 10.times.map(&:to_s).shuffle
+  ary100 = 100.times.map(&:to_s).shuffle
+  ary500 = 500.times.map(&:to_s).shuffle
+  ary1000 = 1000.times.map(&:to_s).shuffle
+  ary2000 = 2500.times.map(&:to_s).shuffle
+  ary3000 = 2500.times.map(&:to_s).shuffle
+  ary5000 = 5000.times.map(&:to_s).shuffle
+  ary10000 = 10000.times.map(&:to_s).shuffle
+  ary20000 = 20000.times.map(&:to_s).shuffle
+  ary50000 = 50000.times.map(&:to_s).shuffle
+  ary100000 = 100000.times.map(&:to_s).shuffle
+
+benchmark:
+  ary2.max: ary2.max
+  ary10.max: ary10.max
+  ary100.max: ary100.max
+  ary500.max: ary500.max
+  ary1000.max: ary1000.max
+  ary2000.max: ary2000.max
+  ary3000.max: ary3000.max
+  ary5000.max: ary5000.max
+  ary10000.max: ary10000.max
+  ary20000.max: ary20000.max
+  ary50000.max: ary50000.max
+  ary100000.max: ary100000.max
+
+loop_count: 10000
+
diff --git a/benchmark/array_min.yml b/benchmark/array_min.yml
new file mode 100644
index 0000000000..53e5072b14
--- /dev/null
+++ b/benchmark/array_min.yml
@@ -0,0 +1,31 @@
+prelude: |
+  ary2 = 2.times.to_a.shuffle
+  ary10 = 10.times.to_a.shuffle
+  ary100 = 100.times.to_a.shuffle
+  ary500 = 500.times.to_a.shuffle
+  ary1000 = 1000.times.to_a.shuffle
+  ary2000 = 2500.times.to_a.shuffle
+  ary3000 = 2500.times.to_a.shuffle
+  ary5000 = 5000.times.to_a.shuffle
+  ary10000 = 10000.times.to_a.shuffle
+  ary20000 = 20000.times.to_a.shuffle
+  ary50000 = 50000.times.to_a.shuffle
+  ary100000 = 100000.times.to_a.shuffle
+  ary1000000 = 1000000.times.to_a.shuffle
+
+benchmark:
+  ary2.min: ary2.min
+  ary10.min: ary10.min
+  ary100.min: ary100.min
+  ary500.min: ary500.min
+  ary1000.min: ary1000.min
+  ary2000.min: ary2000.min
+  ary3000.min: ary3000.min
+  ary5000.min: ary5000.min
+  ary10000.min: ary10000.min
+  ary20000.min: ary20000.min
+  ary50000.min: ary50000.min
+  ary100000.min: ary100000.min
+  ary1000000.min: ary1000000.min
+
+loop_count: 10000
diff --git a/benchmark/array_sample.yml b/benchmark/array_sample.yml
new file mode 100644
index 0000000000..1cd2b34794
--- /dev/null
+++ b/benchmark/array_sample.yml
@@ -0,0 +1,4 @@
+prelude: ary = (1..10_000).to_a
+benchmark:
+  - ary.sample
+  - ary.sample(2)
diff --git a/benchmark/array_sample_100k_10.rb b/benchmark/array_sample_100k_10.rb
new file mode 100644
index 0000000000..5f41ecc32b
--- /dev/null
+++ b/benchmark/array_sample_100k_10.rb
@@ -0,0 +1,2 @@
+arr = [*0...100000]
+10_000.times {arr.sample 10}
diff --git a/benchmark/array_sample_100k_11.rb b/benchmark/array_sample_100k_11.rb
new file mode 100644
index 0000000000..18b1715319
--- /dev/null
+++ b/benchmark/array_sample_100k_11.rb
@@ -0,0 +1,2 @@
+arr = [*0...100000]
+10_000.times {arr.sample 11}
diff --git a/benchmark/array_sample_100k__100.rb b/benchmark/array_sample_100k__100.rb
new file mode 100644
index 0000000000..22863afe89
--- /dev/null
+++ b/benchmark/array_sample_100k__100.rb
@@ -0,0 +1,2 @@
+arr = [*0...100000]
+10_000.times {arr.sample 100}
diff --git a/benchmark/array_sample_100k__1k.rb b/benchmark/array_sample_100k__1k.rb
new file mode 100644
index 0000000000..4cd79e6c67
--- /dev/null
+++ b/benchmark/array_sample_100k__1k.rb
@@ -0,0 +1,2 @@
+arr = [*0...100000]
+10_000.times {arr.sample 1000}
diff --git a/benchmark/array_sample_100k__6k.rb b/benchmark/array_sample_100k__6k.rb
new file mode 100644
index 0000000000..b3d264249e
--- /dev/null
+++ b/benchmark/array_sample_100k__6k.rb
@@ -0,0 +1,2 @@
+arr = [*0...100000]
+10_000.times {arr.sample 6000}
diff --git a/benchmark/array_sample_100k___10k.rb b/benchmark/array_sample_100k___10k.rb
new file mode 100644
index 0000000000..5dd55ec058
--- /dev/null
+++ b/benchmark/array_sample_100k___10k.rb
@@ -0,0 +1,2 @@
+arr = [*0...100000]
+10_000.times {arr.sample 10_000}
diff --git a/benchmark/array_sample_100k___50k.rb b/benchmark/array_sample_100k___50k.rb
new file mode 100644
index 0000000000..1506732c3c
--- /dev/null
+++ b/benchmark/array_sample_100k___50k.rb
@@ -0,0 +1,2 @@
+arr = [*0...100000]
+10_000.times {arr.sample 50_000}
diff --git a/benchmark/bm_array_shift.rb b/benchmark/array_shift.rb
index 798bb9e3f4..798bb9e3f4 100644
--- a/benchmark/bm_array_shift.rb
+++ b/benchmark/array_shift.rb
diff --git a/benchmark/array_small_and.rb b/benchmark/array_small_and.rb
new file mode 100644
index 0000000000..e53a6edae6
--- /dev/null
+++ b/benchmark/array_small_and.rb
@@ -0,0 +1,17 @@
+MIN_SIZE = ENV.fetch('SMALL_ARRAY_MIN', 0).to_i
+MAX_SIZE = ENV.fetch('SMALL_ARRAY_MAX', 16).to_i
+ITERATIONS = ENV.fetch('SMALL_ARRAY_ITERATIONS', 100).to_i
+
+ARRAYS = (MIN_SIZE..MAX_SIZE).map do |size1|
+  (MIN_SIZE..MAX_SIZE).map do |size2|
+    [Array.new(size1) { rand(MAX_SIZE) }, Array.new(size2) { rand(MAX_SIZE) }]
+  end
+end
+
+ITERATIONS.times do
+  ARRAYS.each do |group|
+    group.each do |arr1, arr2|
+      arr1 & arr2
+    end
+  end
+end
diff --git a/benchmark/array_small_diff.rb b/benchmark/array_small_diff.rb
new file mode 100644