September 2025 - ruby-core - ml.ruby-lang.org

[ruby-core:123314] [Ruby Bug#21613] TestGc#test_exception_in_finalizer_procs and TestGc#test_exception_in_finalizer_method fail with ASAN
by Eregon (Benoit Daloze) 21 Sep '25

21 Sep '25

Issue #21613 has been reported by Eregon (Benoit Daloze). ---------------------------------------- Bug #21613: TestGc#test_exception_in_finalizer_procs and TestGc#test_exception_in_finalizer_method fail with ASAN https://bugs.ruby-lang.org/issues/21613 * Author: Eregon (Benoit Daloze) * Status: Open * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- See https://github.com/ruby/ruby-dev-builder/actions/runs/17883721287/job/50854… ``` 1) Failure: TestGc#test_exception_in_finalizer_procs [/home/runner/work/ruby-dev-builder/ruby-dev-builder/test/ruby/test_gc.rb:828]: pid 40237 exit 0. 1. [1/2] Assertion for "stdout" | <["c1", "c2"]> expected but was | <["c1"]>. 2) Failure: TestGc#test_exception_in_finalizer_method [/home/runner/work/ruby-dev-builder/ruby-dev-builder/test/ruby/test_gc.rb:848]: pid 40260 exit 0. 1. [1/2] Assertion for "stdout" | <["c1", "c2"]> expected but was | <["c1"]>. Finished tests in 630.155129s, 46.2553 tests/s, 9737.2404 assertions/s. 29148 tests, 6135972 assertions, 2 failures, 0 errors, 178 skips ``` Oddly enough https://ci.rvm.jp/results/trunk_asan@ruby-sp1 doesn't fail. This is not the first time, it's been many times that job found issues not caught in ruby/ruby CI, so I would like to request adding a ASAN GHA job doing the same as https://github.com/ruby/ruby-dev-builder in ruby/ruby so such failures are found earlier and do not block ruby-dev-builder and setup-ruby. If not, I will be forced to drop ASAN support in setup-ruby. For now I will exclude these tests on ASAN to unblock, but it's a bit hacky because there seems to be no predicate to detect ASAN, except `Thread.asan?` with `require '-test-/stack'` (= hacky). -- https://bugs.ruby-lang.org/

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[ruby-core:122343] [Ruby Misc#21385] Namespace: Suggesting a rename
by fxn (Xavier Noria) 20 Sep '25

20 Sep '25

Issue #21385 has been reported by fxn (Xavier Noria). ---------------------------------------- Misc #21385: Namespace: Suggesting a rename https://bugs.ruby-lang.org/issues/21385 * Author: fxn (Xavier Noria) * Status: Open ---------------------------------------- I'd like to suggest a rename of namespaces. The word "namespace" is already taken in Ruby. We say that classes and modules act as or represent. Constant paths nest them in practice. We say that it is a best practice that gems create their own namespace, etc. If the feature goes ahead with this name, the above sentences, well-established in the Ruby community, will start to sound confusing, because that meaning of "namespace" stays. If you look at the index in Matz's book, "namespaces" is indexed in pages 248–250. Title of section 7.5.1 is "Modules as Namespaces". Besides, I have had a few experiences explaining the proposal to people, and quickly realizing they assume this is something like C++ namespaces or Java packages. Then, I have to undo that mental model and start all over saying "forget that mental model". Those are like our constant paths, only more simple and strict. I think it may also be confusing in this sense (though this could be OK if it wasn't for the previous point.) To be constructive: Some alternative names that I have thought about are "isolates", "shields", or "cells". ("sandboxes" is close, but may have security connotations you do not want to suggest.) -- https://bugs.ruby-lang.org/

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[ruby-core:123257] [Ruby Misc#21606] DevMeeting-2025-10-23
by mame (Yusuke Endoh) 20 Sep '25

20 Sep '25

Issue #21606 has been reported by mame (Yusuke Endoh). ---------------------------------------- Misc #21606: DevMeeting-2025-10-23 https://bugs.ruby-lang.org/issues/21606 * Author: mame (Yusuke Endoh) * Status: Open ---------------------------------------- # The next dev meeting **Date: 2025/10/23 13:00-17:00** (JST) Log: *TBD* - Dev meeting *IS NOT* a decision-making place. All decisions should be done at the bug tracker. - Dev meeting is a place we can ask Matz, nobu, nurse and other developers directly. - Matz is a very busy person. Take this opportunity to ask him. If you can not attend, other attendees can ask instead of you (if attendees can understand your issue). - We will write a record of the discussion in the file or to each ticket in English. - All activities are best-effort (keep in mind that most of us are volunteer developers). - The date, time and place of the meeting are scheduled according to when/where we can reserve Matz's time. - *DO NOT* discuss then on this ticket, please. # Call for agenda items If you have a ticket that you want matz and committers to discuss, please post it into this ticket in the following format: ``` * [Ticket ref] Ticket title (your name) * Comment (A summary of the ticket, why you put this ticket here, what point should be discussed, etc.) ``` Example: ``` * [Feature #14609] `Kernel#p` without args shows the receiver (ko1) * I feel this feature is very useful and some people say :+1: so let discuss this feature. ``` - It is recommended to add a comment by 2025/10/20. We hold a preparatory meeting to create an agenda a few days before the dev-meeting. - The format is strict. We'll use [this script to automatically create an markdown-style agenda](https://gist.github.com/mame/b0390509ce1491b43610b9ebb665eb86). We may ignore a comment that does not follow the format. - Your comment is mandatory. We cannot read all discussion of the ticket in a limited time. We appreciate it if you could write a short summary and update from a previous discussion. -- https://bugs.ruby-lang.org/

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[ruby-core:123311] Re: Revised Paperwork.pdf
by Ruby-core 19 Sep '25

19 Sep '25

1 0

[ruby-core:123310] Re: Revised Paperwork.pdf
by Ruby-core 19 Sep '25

19 Sep '25

1 0

[ruby-core:123306] [Ruby Bug#21612] Make sure we never context switch while holding the VM lock
by luke-gru (Luke Gruber) 19 Sep '25

19 Sep '25

Issue #21612 has been reported by luke-gru (Luke Gruber). ---------------------------------------- Bug #21612: Make sure we never context switch while holding the VM lock https://bugs.ruby-lang.org/issues/21612 * Author: luke-gru (Luke Gruber) * Status: Open * Target version: 3.5 * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- ## The Problem We're seeing errors in our application that uses ractors. The errors look like: ``` [BUG] unexpected situation - recordd:1 current:0 error.c:1097 rb_bug_without_die_internal vm_sync.c:275 disallow_reentry eval_intern.h:136 rb_ec_vm_lock_rec_check eval_intern.h:147 rb_ec_tag_state vm.c:2619 rb_vm_exec vm.c:1702 rb_yield eval.c:1173 rb_ensure ``` We concluded that there was context switching going on while a thread held the VM lock. During the investigation into the issue, we added assertions in the code that we never yield to another thread with the VM lock held. We enabled these VM lock assertions even in single ractor mode. These assertions were failing in a few places, but most notably in finalizers. Finalizers are running with the VM lock held, and they were context switching and causing this issue. ## Why Is This Bad? There are a few reasons we shouldn't be able to context switch while holding the VM lock. In single-ractor mode with threads A and B: 1) Anything in this critical section should be thought of as a transaction related to the memory that's changed inside. if A has the lock, manipulates some global memory and yields to B with the lock still taken and without finishing the memory updates and then B takes it and starts writing to the same memory, the state of this global memory could be corrupted. Currently we don't actually take the VM lock in single-ractor mode, but that doesn't mean these issues can't happen. Yielding to another thread in the middle of manipulating global memory *can* still happen and it causes similar issues. In multi-ractor mode with ractors A and B: 1) We get the same issues as in single-ractor mode. 2) We can also get deadlocks if A has the lock, yields to B and B is blocked waiting on the lock. Unfortunately, many things can cause context switching in Ruby, so what is safe to call when the VM lock is taken? ## Guidelines I've come up with some guidelines. With the VM lock held, You should be able to: * Create ruby objects, call `ruby_xmalloc`, etc. * Jump using `EC_JUMP_TAG`. The lock will automatically be unlocked depending on how far up the call stack you locked it and where you're jumping to. * Check ruby interrupts. Since jumping can pop ruby frames and popping frames checks interrupts, you are allowed. It should never context switch with the VM lock held, even if the ruby thread's quantum is up. You shouldn't be able to: * Call any ruby method or enter Ruby's VM loop. For example, `rb_funcall` is not allowed, nor is `rb_warn` (it can call ruby code). `rb_sprintf` is not allowed because it can call `rb_inspect`. * Call `rb_nogvl` * Enter any blocking operation managed by Ruby. * Call a ruby-level mechanism that can context switch, like `rb_mutex_lock`. ## The Fix Of course, unlocking during finalizers is the main fix but there are other places that also need unlocking. I think adding assertions that the VM lock is not held will be important in finding these bugs and not creating regressions in the future. We don't have to add lots of these, just in a few places. These assertions, which only run in debug mode, should also run when in single-ractor mode. ## Future Work I think some documentation would be helpful for what is and isn't allowed while holding the VM lock and other locks in the cruby source. I am currently working on a `Concurrency Guide` for cruby developers that includes this info. It will not go over every lock, just the VM lock and the "all other locks" category. -- https://bugs.ruby-lang.org/

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[ruby-core:123305] 659" x 875" Revised Paperwork.pdf
by ruby-core 19 Sep '25

19 Sep '25

1 0

[ruby-core:121234] [Ruby master Bug#21168] Prism doesn't require argument parentheses (in some cases) when a block is present but parse.y does
by Earlopain (Earlopain _) 19 Sep '25

19 Sep '25

Issue #21168 has been reported by Earlopain (Earlopain _). ---------------------------------------- Bug #21168: Prism doesn't require argument parentheses (in some cases) when a block is present but parse.y does https://bugs.ruby-lang.org/issues/21168 * Author: Earlopain (Earlopain _) * Status: Open * ruby -v: ruby 3.4.2 (2025-02-15 revision d2930f8e7a) +PRISM [x86_64-linux] * Backport: 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- It's a bit more than that but explaining it in full would be a bit much. Instead, see this: ```rb foo( bar baz do end ) ``` ```sh $ ruby -c --parser=prism test.rb Syntax OK $ ruby -c --parser=parse.y test.rb ruby: test.rb:2: syntax error, unexpected 'do' for block, expecting ')' (SyntaxError) bar baz do ^~ ``` OTOH, this is consistently rejected: ```rb [ foo bar do end, ] # And also foo || bar baz do end ``` -- https://bugs.ruby-lang.org/

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[ruby-core:123299] [Ruby Bug#21611] Ruby 3.4.6 can't be built with GCC 15.2.1
by watson1978 (Shizuo Fujita) 19 Sep '25

19 Sep '25

Issue #21611 has been reported by watson1978 (Shizuo Fujita). ---------------------------------------- Bug #21611: Ruby 3.4.6 can't be built with GCC 15.2.1 https://bugs.ruby-lang.org/issues/21611 * Author: watson1978 (Shizuo Fujita) * Status: Open * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- Arch Linux provides GCC 15.2.1. https://archlinux.org/packages/core/x86_64/gcc/ When I build Ruby 3.4.6 with GCC 15.2.1, it cause error: ### How to Reproduce Here is a Dockerfile to reproduce the error: ``` FROM archlinux:latest RUN pacman -Syu --noconfirm RUN pacman -S --noconfirm curl base-devel libffi zlib openssl readline libyaml RUN curl -O https://cache.ruby-lang.org/pub/ruby/3.4/ruby-3.4.6.tar.gz RUN tar -xvzf ruby-3.4.6.tar.gz RUN cd ruby-3.4.6 && ./configure && make -j && make install ``` Then, run `docker build -t ruby . --platform=linux/amd64` command to reproduce the error. ``` $ docker build -t ruby . --platform=linux/amd64 [+] Building 362.6s (9/9) FINISHED docker:desktop-linux => [internal] load build definition from Dockerfile 0.0s => => transferring dockerfile: 332B 0.0s => [internal] load metadata for docker.io/library/archlinux:latest 0.3s => [internal] load .dockerignore 0.0s => => transferring context: 2B 0.0s => [1/6] FROM docker.io/library/archlinux:latest@sha256:8fe9851fcd8bd23ea0e6bfa99483d8778e40b45e0fd7bb8188c94cbdd8c25a38 0.0s => => resolve docker.io/library/archlinux:latest@sha256:8fe9851fcd8bd23ea0e6bfa99483d8778e40b45e0fd7bb8188c94cbdd8c25a38 0.0s => CACHED [2/6] RUN pacman -Syu --noconfirm 0.0s => [3/6] RUN pacman -S --noconfirm curl base-devel libffi zlib openssl readline libyaml 24.4s => [4/6] RUN curl -O https://cache.ruby-lang.org/pub/ruby/3.4/ruby-3.4.6.tar.gz 1.2s => [5/6] RUN tar -xvzf ruby-3.4.6.tar.gz 1.1s => ERROR [6/6] RUN cd ruby-3.4.6 && ./configure && make -j && make install 335.5s ------ > [6/6] RUN cd ruby-3.4.6 && ./configure && make -j && make install: 0.765 checking for ruby... false 0.888 checking build system type... x86_64-pc-linux-gnu 1.452 checking host system type... x86_64-pc-linux-gnu 1.452 checking target system type... x86_64-pc-linux-gnu ... 288.3 compiling enc/ascii.c 300.8 gcc: fatal error: Killed signal terminated program cc1 301.1 compilation terminated. 301.2 gcc: fatal error: Killed signal terminated program cc1 301.2 compilation terminated. 301.5 make: *** [Makefile:489: complex.o] Error 1 301.5 In file included from ./include/ruby/internal/assume.h:29, 301.5 from ./include/ruby/backward/2/assume.h:24, 301.5 from ./include/ruby/defines.h:72, 301.5 from ./include/ruby/ruby.h:25, 301.5 from ./include/ruby/encoding.h:19, 301.5 from encindex.h:14, 301.5 from compile.c:19: 301.5 compile.c: In function ‘ibf_load_catch_table’: 301.6 make: *** Waiting for unfinished jobs.... 301.6 make: *** [Makefile:489: io.o] Error 1 301.7 compile.c:13163:39: warning: taking address of packed member of ‘struct iseq_catch_table’ may result in an unaligned pointer value [-Waddress-of-packed-member] 301.7 13163 | RB_OBJ_WRITE(parent_iseq, &table->entries[i].iseq, catch_iseq); 301.7 ./include/ruby/internal/cast.h:31:29: note: in definition of macro ‘RBIMPL_CAST’ 301.7 31 | # define RBIMPL_CAST(expr) (expr) 301.7 | ^~~~ 301.7 compile.c:13163:13: note: in expansion of macro ‘RB_OBJ_WRITE’ 301.7 13163 | RB_OBJ_WRITE(parent_iseq, &table->entries[i].iseq, catch_iseq); 301.7 | ^~~~~~~~~~~~ 301.8 gcc: fatal error: Killed signal terminated program cc1 301.8 compilation terminated. 301.9 make: *** [Makefile:489: process.o] Error 1 309.6 gcc: fatal error: Killed signal terminated program cc1 309.6 compilation terminated. 309.6 make: *** [Makefile:489: vm.o] Error 1 313.7 gcc: fatal error: Killed signal terminated program cc1 313.7 compilation terminated. 313.7 make: *** [Makefile:489: string.o] Error 1 334.5 At top level: 334.5 cc1: note: unrecognized command-line option ‘-Wno-self-assign’ may have been intended to silence earlier diagnostics 334.5 cc1: note: unrecognized command-line option ‘-Wno-parentheses-equality’ may have been intended to silence earlier diagnostics 334.5 cc1: note: unrecognized command-line option ‘-Wno-constant-logical-operand’ may have been intended to silence earlier diagnostics ------ Dockerfile:7 -------------------- 5 | RUN curl -O https://cache.ruby-lang.org/pub/ruby/3.4/ruby-3.4.6.tar.gz 6 | RUN tar -xvzf ruby-3.4.6.tar.gz 7 | >>> RUN cd ruby-3.4.6 && ./configure && make -j && make install 8 | -------------------- ERROR: failed to build: failed to solve: ResourceExhausted: process "/bin/sh -c cd ruby-3.4.6 && ./configure && make -j && make install" did not complete successfully: cannot allocate memory ``` -- https://bugs.ruby-lang.org/

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[ruby-core:123298] ml.ruby-lang.org: Warning ❗️
by ml.ruby-lang.org 19 Sep '25

19 Sep '25

1 0