4.0.4

Ruby 4.0.4 portable binaries

Released by Ruby: 2026-05-11

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What's Changed

• Bug #21955: Fiber#transfer: machine stack not released when fiber terminates, causing FiberError: can't set a guard page - Ruby - Ruby Issue Tracking System
• Bug #21964: Fiber stack acquire can expand unnecessarily - Ruby - Ruby Issue Tracking System
• Bug #21971: Fix regexp performance regression for patterns starting with s/k - Ruby - Ruby Issue Tracking System
• Bug #21961: Marshal.load freeze option fail to freeze linked strings - Ruby - Ruby Issue Tracking System
• Bug #21959: rb_internal_thread_event_hooks_rw_lock is not reinitialized after fork causing deadlocks - Ruby - Ruby Issue Tracking System
• Bug #21954: NoMethodError instead of Gem::LoadError on gem activation problem in Ruby 4.0.2 - Ruby - Ruby Issue Tracking System
• Bug #21844: Inconsistent ArgumentError message for Data::define.new - Ruby - Ruby Issue Tracking System
• Bug #21992: Defining BasicObject#initialize causes segmentation fault - Ruby - Ruby Issue Tracking System
• Bug #22018: ISeq created via RubyVM::InstructionSequence.compile don't support coverage - Ruby - Ruby Issue Tracking System
• Bug #21985: RubyVM::AST negative numbers do not include - in location - Ruby - Ruby Issue Tracking System
• Bug #21986: RubyVM::AST incorrect location for literals followed by modifier if - Ruby - Ruby Issue Tracking System
• Bug #21933: Ruby::Box: named capture local variable can become nil after non-matching lines - Ruby - Ruby Issue Tracking System
• Bug #21940: Ruby::Box: $_ returns stale value due to gvar_tbl caching - Ruby - Ruby Issue Tracking System
• Bug #22004: parse.y doesn't executes loop body with while true || true condition - Ruby - Ruby Issue Tracking System
• Bug #21952: Ruby::Box double free at process exit when fiddle/import is required in multiple boxes - Ruby - Ruby Issue Tracking System
• Bug #22003: .bundle extensions not built when doing out-of-source build - Ruby - Ruby Issue Tracking System
• Bug #22002: argument stack underflow (-1) - 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@v4.0.3...v4.0.4

Build revision: 4.0.4-4
Build fingerprint: v1-ffdde8ff6d4432c191b047dc75ec2ab3f0a73635831848804969e30577bc1bc8