4.0.6-2

Ruby 4.0.6 portable binaries

Released by Ruby: 2026-07-14

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What's Changed

• Bug #22070: Thread.each_caller_location(1, 1) segfaults when called from a cfunc - Ruby - Ruby Issue Tracking System
• Bug #22075: heap-use-after-free in rb_vm_ci_lookup under parallel Ractors - Ruby - Ruby Issue Tracking System
• Bug #22076: defined? returns nil for protected methods defined in a module even when callable - Ruby - Ruby Issue Tracking System
• Bug #22072: [BUG] should have cvar cache entry - Ruby - Ruby Issue Tracking System
• Bug #22074: YJIT misaligns locals when there are > 256 local variables - Ruby - Ruby Issue Tracking System
• Bug #22064: GC compaction breaks compare-by-identity sets - Ruby - Ruby Issue Tracking System
• Bug #22084: invokesuper from define_method in Ractor can call wrong super method or crash - Ruby - Ruby Issue Tracking System
• Bug #22092: Array#sum takes slow path, does not perform compensated summation of Float elements when init argument is a Float - Ruby - Ruby Issue Tracking System
• Bug #14635: Float#round(n) returns a wrong result when n is big - Ruby - Ruby Issue Tracking System
• Bug #22079: Float#ceil gives incorrect result - Ruby - Ruby Issue Tracking System
• Bug #22096: Freeing a mutex locked by a fiber inside fiber scheduler can crash - Ruby - Ruby Issue Tracking System
• Bug #21996: Crash when modifying instance variables during inspect or Marshal dump - Ruby - Ruby Issue Tracking System
• Bug #22101: ASAN heap-use-after-free in rb_data_free after TypedData dfree frees dynamic rb_data_type_t - Ruby - Ruby Issue Tracking System
• Bug #22103: Constant-folded /o regexp crashes with dupstring of a Regexp - Ruby - Ruby Issue Tracking System
• Bug #21991: $! stays as the first exception in Ruby Box - Ruby - Ruby Issue Tracking System
• Feature #21881: Split the root box into the (newer) root box and the master of copied user boxes - Ruby - Ruby Issue Tracking System
• Bug #22120: Segfault caused by ar_find_entry_hint() not checking for conversion to st_table - Ruby - Ruby Issue Tracking System
• Bug #22129: error_highlight raises NotImplementedError for ArgumentErrors that get wrapped - Ruby - Ruby Issue Tracking System
• Bug #21864: Inconsistencies in type coercion error messages for integers - Ruby - Ruby Issue Tracking System
• Bug #21882: IO::Buffer#locked leaves the buffer locked when the block raises - Ruby - Ruby Issue Tracking System
• Bug #22127: parse.y regexp crash on invalid encoding - Ruby - Ruby Issue Tracking System
• Bug #22126: Stack underflow for partial DCE and loops - Ruby - Ruby Issue Tracking System
• Bug #22124: void value missed in parse.y - Ruby - Ruby Issue Tracking System
• Bug #22104: Segfault in PRISM while Bootsnap compiles aws-sdk client_api.rb - Ruby - Ruby Issue Tracking System
• Bug #21685: Unnecessary context-switching, especially bad on multi-core machines. - Ruby - Ruby Issue Tracking System
• Bug #22099: Keyword-only method silently accepts a positional argument - Ruby - Ruby Issue Tracking System
• Bug #22183: parse.y interpolation inside lambda literal - Ruby - Ruby Issue Tracking System
• Bug #22181: SEGV in branch peephole optimization due to label/insn struct aliasing - Ruby - Ruby Issue Tracking System
• Bug #22133: Ruby's default SIGINT handling ignores Thread.handle_interrupt masking. - Ruby - Ruby Issue Tracking System
• Bug #22189: Enumerator::Lazy#to_enum does not accept method names as strings - Ruby - Ruby Issue Tracking System
• Bug #22191: Signal.trap(:EXIT) exception only shown if at_exit also raises - Ruby - Ruby Issue Tracking System

Note: This list is automatically generated by tool/gen-github-release.rb. Because of this, some commits may be missing.

Full Changelog

ruby/ruby@v4.0.5...v4.0.6

Build revision: 4.0.6-2