4.0.0-preview3

Ruby 4.0.0-preview3 portable binaries

Released by Ruby: 2025-12-25

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What's Changed

• YJIT: omit single ractor mode assumption for proc#call by luke-gruber · Pull Request #15092
• ZJIT: Inline BasicObject#! by tekknolagi · Pull Request #15201
• Bug #21697: nmake up will update broken revision.h - Ruby - Ruby Issue Tracking System
• ZJIT: Count all calls to C functions from generated code by tekknolagi · Pull Request #15240
• ZJIT: Add Iongraph compatibility by aidenfoxivey · Pull Request #14999
• Feature #20408: Add heap_live_slots to GC.stat_heap - Ruby - Ruby Issue Tracking System
• Bug #21375: Set[] does not call #initialize - Ruby - Ruby Issue Tracking System
• ZJIT: Deduplicate successor and predecessor sets by aidenfoxivey · Pull Request #15263
• [DOC] Tweaks for String#upcase by BurdetteLamar · Pull Request #15244
• Fix multiple bugs in IO::Buffer.map and update its documentation by trinistr · Pull Request #15264
• ZJIT: Inline String#empty? by tekknolagi · Pull Request #15283
• ZJIT: Specialize monomorphic DefinedIvar by tekknolagi · Pull Request #15281
• ZJIT: Inline Thread.current by tekknolagi · Pull Request #15272
• ZJIT: Inline Integer#<< for constant rhs by tekknolagi · Pull Request #15258
• Bug #21705: UNIXServer.open(nil) segfaults on Windows - Ruby - Ruby Issue Tracking System
• Bug #21703: RUBY_CRASH_REPORT does not work when shelling out in some cases - Ruby - Ruby Issue Tracking System
• Bug #21622: Prism wrongly accepts command call to be a key of keyword argument - Ruby - Ruby Issue Tracking System
• Revert "Fix stdatomic case in rbimpl_atomic_u64_fetch_add" by tekknolagi · Pull Request #15311
• Bug #21694: Crash when looking up super method from BasicObject - Ruby - Ruby Issue Tracking System
• ZJIT: Specialize setinstancevariable when ivar is already in shape by tekknolagi · Pull Request #15290
• [DOC] Use Aliki as the documentation website theme by st0012 · Pull Request #15319
• Bug #21707: Destructuring assignment of SimpleDelegator wrapped array bug with YJIT - Ruby - Ruby Issue Tracking System
• Eliminate redundant work and branching when marking T_OBJECT by luke-gruber · Pull Request #15274
• Fix a ractor barrier issue during VM cleanup. by luke-gruber · Pull Request #15091
• ZJIT: Count fallback reasons for set/get/definedivar by tekknolagi · Pull Request #15324
• Fix argument handling in IO::Buffer#each_byte by tmtm · Pull Request #15309
• Reorganize page documentations by st0012 · Pull Request #15154
• [DOC] Remove unneeded filename from rdoc-ref links by st0012 · Pull Request #15339
• Bump RDoc version to 6.16.1 by st0012 · Pull Request #15344
• Bug #21718: TypeError:wrong argument type ... (expected Array) - Ruby - Ruby Issue Tracking System
• Clean up scheduler during terminate_atfork_i. by samuel-williams-shopify · Pull Request #15354
• Add rb_ec_close function to manage execution context cleanup. by samuel-williams-shopify · Pull Request #15253
• ZJIT: Optimize variadic cfunc Send calls into CCallVariadic by st0012 · Pull Request #14898
• Speedup RBASIC_FIELDS_COUNT by luke-gruber · Pull Request #15273
• ZJIT: Standardize method dispatch insns' recv field by st0012 · Pull Request #15334
• ZJIT: Fix erroneous version number for Iongraph by aidenfoxivey · Pull Request #15357
• Test CC invalidation for singleton classes of objects by luke-gruber · Pull Request #15360
• Cache array length in rb_ary_join by luke-gruber · Pull Request #15362
• [DOC] About Float Imprecision by BurdetteLamar · Pull Request #15293
• Bug #21710: Segfault when reading object_id after it is set inside RUBY_INTERNAL_EVENT_NEWOBJ - Ruby - Ruby Issue Tracking System
• ZJIT: Optimize NewArray to use rb_ec_ary_new_from_values by goshanraj-g · Pull Request #15391
• ZJIT: Inline Kernel#class by tekknolagi · Pull Request #15397
• ZJIT: Optimize setivar with shape transition by tekknolagi · Pull Request #15375
• Bug #21758: Prism fails to parse heredoc within %Q literal split by another heredoc - Ruby - Ruby Issue Tracking System
• Bug #21764: encoding of warning for depreciated global variables is not set - Ruby - Ruby Issue Tracking System
• Remove mismatched indentations warning by etiennebarrie · Pull Request #15410
• Take VM lock in class_switch_superclass by luke-gruber · Pull Request #15356
• Fix thread scheduler issue with thread_sched_wait_events by luke-gruber · Pull Request #15392
• Update NEWS.md for Ruby 4.0.0 by mame · Pull Request #15369
• Remove fiber scheduler and set fiber to blocking in forked process by noteflakes · Pull Request #15385
• Feature #20750: Allow rb_thread_call_with_gvl to work when thread already has GVL - Ruby - Ruby Issue Tracking System
• ZJIT: Include local variable names in Get|SetLocal insn's print value by st0012 · Pull Request #15423
• Add support for u128, U128, s128 and S128 integers to IO::Buffer. by samuel-williams-shopify · Pull Request #15399
• [DOC] Update NEWS about ZJIT by k0kubun · Pull Request #15426
• Fix io_pwrite fiber scheduler hook. by samuel-williams-shopify · Pull Request #15428
• Yield to scheduler if interrupts are pending. by ioquatix · Pull Request #14700
• Re-introduce support for io_close hook. by samuel-williams-shopify · Pull Request #15434
• Bump RDoc version to 6.17.0 by st0012 · Pull Request #15439
• ZJIT: Avoid redundant SP save in codegen by st0012 · Pull Request #15448
• Update ZJIT docs by tekknolagi · Pull Request #15449
• Remove unused local variables in test/ruby/test_io_buffer.rb by etiennebarrie · Pull Request #15451
• ZJIT: Add codegen for FixnumDiv by dddictionary · Pull Request #15452
• Bug #21771: pg-1.6.2 testsuite segfaults in ruby4.0.0dev - Ruby - Ruby Issue Tracking System
• ZJIT: Show send fallback reason in HIR dump by rwstauner · Pull Request #15454
• Bug #21757: Splatted args array is mutated when passing unexpected kwargs - Ruby - Ruby Issue Tracking System
• Bug #21446: StackOverflow when changing visibility in reopened refinement - Ruby - Ruby Issue Tracking System
• Bug #21374: FrozenError message is inconsistent when a singleton method is defined on a frozen object - Ruby - Ruby Issue Tracking System
• ZJIT: Add dump to file for --zjit-stats by aidenfoxivey · Pull Request #15414
• Fix typo in thread_pthread.c by yujiteshima · Pull Request #15465
• ZJIT: Prohibit ZJIT support with USE_FLONUM=0 by k0kubun · Pull Request #15471
• Bug #21708: Ruby 3.4 Forwardable: setter delegations trigger SyntaxError from forwardable/impl.rb - Ruby - Ruby Issue Tracking System
• ZJIT: Check if shape is too complex before reading ivar by index by tekknolagi · Pull Request #15478
• ZJIT: Exclude failing ruby-bench benchmarks by k0kubun · Pull Request #15479
• ubuntu.yml: Add a ruby-bench job without ZJIT by k0kubun · Pull Request #15480
• ZJIT: Use inline format args by alexcrocha · Pull Request #15482
• ZJIT: Fold LoadField on frozen objects to constants by tobi · Pull Request #15483
• ZJIT: Re-compile ISEQs invalidated by PatchPoint by k0kubun · Pull Request #15459
• Feature #21552: allow String.strip and similar to take a parameter similar to String.delete - Ruby - Ruby Issue Tracking System
• Bug #21712: Prism and parse.y inconsistency in command call with block and .() - Ruby - Ruby Issue Tracking System
• Bug #19558: str.dump.undump crashes when str contains both Unicode and ASCII control characters - Ruby - Ruby Issue Tracking System
• Fix Set#^ to not mutate its argument by gildesmarais · Pull Request #15296
• Stop bumping RUBY_PATCHLEVEL in release versions by k0kubun · Pull Request #15502
• ZJIT: Check method visibility when optimizing sends by tekknolagi · Pull Request #15501
• make-snapshot: Update the tag format for Ruby 4.0+ by k0kubun · Pull Request #15514
• ZJIT: Don't specialize calls with kwsplat by rwstauner · Pull Request #15513
• Bug #21776: Binding#local_variable_defined? still supports numbered parameters - Ruby - Ruby Issue Tracking System
• Avoid race condition in test_without_handle_interrupt_signal_works. by ioquatix · Pull Request #15504
• Bug #21049: Reconsider handling of the numbered parameters and "it" parameter in Binding#local_variables - Ruby - Ruby Issue Tracking System
• Fix binding.implicit_parameters_get/defined segfault when wrong name string is passed by tompng · Pull Request #15530
• ZJIT: Add Shape type to HIR by tekknolagi · Pull Request #15528
• Feature #21678: Enumerable#rfind - Ruby - Ruby Issue Tracking System
• move th->event_serial to rb_thread_sched_item by luke-gruber · Pull Request #15500
• Bug #21775: Procs of type ifunc can access unshareable values - Ruby - Ruby Issue Tracking System
• Fewer calls to GET_EC() and GET_THREAD() by luke-gruber · Pull Request #15506
• Bug #21772: ruby: YJIT has panicked StackOpnd(1) should be a heap object, but was ImmSymbol for VALUE(137647867319760) - Ruby - Ruby Issue Tracking System
• ZJIT: Allow ccalls above 7 arguments by aidenfoxivey · Pull Request #15312
• ZJIT: Nil-fill locals in direct send by rwstauner · Pull Request #15536
• Feature #21701: Enumerator.produce accepts an optional size keyword argument - Ruby - Ruby Issue Tracking System
• Feature #20925: Allow boolean operators at beginning of line to continue previous line - Ruby - Ruby Issue Tracking System
• Bug #21779: Do not export functions from statically linked extensions - Ruby - Ruby Issue Tracking System
• Fix Socket.tcp cleanup after Thread#kill by luke-gruber · Pull Request #15131
• ZJIT: Add iongraph-generating Ruby script by tekknolagi · Pull Request #15466
• Point people to redmine on ZJIT docs by tekknolagi · Pull Request #15499
• Bug #21266: YJIT GC safety crash with proc objects as block argument - Ruby - Ruby Issue Tracking System
• Feature #6012: Proc#source_location also return the column - Ruby - Ruby Issue Tracking System
• Fix: Do not pass negative timeout to Addrinfo#connect_internal by shioimm · Pull Request #15578
• Add the class variable and the class itself in Ractor::IsolationError by etiennebarrie · Pull Request #15562
• Add the instance variable name and the module in Ractor::IsolationError by etiennebarrie · Pull Request #15563
• Bug #21715: Miscompilation on x86-64-v2 due to undefined behavior in search_nonascii in string.c - Ruby - Ruby Issue Tracking System
• Bug #19112: Ractor garbage collection breaks/disables all active tracepoints - Ruby - Ruby Issue Tracking System
• Bug #21782: Ractor::IsolationError reports incorrect path for constants found through upwards search - Ruby - Ruby Issue Tracking System
• Fix: Recalculate the timeout duration considering open_timeout by shioimm · Pull Request #15596
• Bug #21787: IO::Buffer Integer Overflow in Range Validation Leads to Out-of-Bounds Memory Access - Ruby - Ruby Issue Tracking System
• Socket.tcp and TCPSocket.new raises IO::TiemoutError with user specified timeout by shioimm · Pull Request #15602
• Add host information to timeout error messages in TCPSocket.new and Socket.tcp by shioimm · Pull Request #15582
• Bug #21780: Change the default size of Enumerator.produce back to infinity - Ruby - Ruby Issue Tracking System
• Update NEWS.md for Socket by shioimm · Pull Request #15608
• Improve NEWS.md for Socket by shioimm · Pull Request #15610
• ObjectSpace.{dump,dump_all,dump_shapes} needs vm barrier. by luke-gruber · Pull Request #15569
• Update bundled bigdecimal and rbs by tompng · Pull Request #15611
• [DOC] Small changes to docs for ObjectSpace#each_object by luke-gruber · Pull Request #15564
• Adjust Set documentation by zverok · Pull Request #15547

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

Full Changelog

ruby/ruby@v4.0.0-preview2...v4.0.0-preview3