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

[ruby-core:120694] [Ruby master Bug#21039] Ractor.make_shareable breaks block semantics (seeing updated captured variables) of existing blocks
by Eregon (Benoit Daloze) 27 Aug '25

27 Aug '25

Issue #21039 has been reported by Eregon (Benoit Daloze). ---------------------------------------- Bug #21039: Ractor.make_shareable breaks block semantics (seeing updated captured variables) of existing blocks https://bugs.ruby-lang.org/issues/21039 * Author: Eregon (Benoit Daloze) * Status: Open * Assignee: ko1 (Koichi Sasada) * Backport: 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- ```ruby def make_counter count = 0 nil.instance_exec do [-> { count }, -> { count += 1 }] end end get, increment = make_counter reader = Thread.new { sleep 0.01 loop do p get.call sleep 0.1 end } writer = Thread.new { loop do increment.call sleep 0.1 end } ractor_thread = Thread.new { sleep 1 Ractor.make_shareable(get) } sleep 2 ``` This prints: ``` 1 2 3 4 5 6 7 8 9 10 10 10 10 10 10 10 10 10 10 10 ``` But it should print 1..20, and indeed it does when commenting out the `Ractor.make_shareable(get)`. This shows a given block/Proc instance is concurrently broken by `Ractor.make_shareable`, IOW Ractor is breaking fundamental Ruby semantics of blocks and their captured/outer variables or "environment". It's expected that `Ractor.make_shareable` can `freeze` objects and that may cause some FrozenError, but here it's not a FrozenError, it's wrong values being read. I think what should happen instead is that `Ractor.make_shareable` should create a new Proc and mutate that. However, if the Proc is inside some other object and not just directly the argument, that wouldn't work (like `Ractor.make_shareable([get])`). So I think one fix would to be to only accept Procs for `Ractor.make_shareable(obj, copy: true)`. FWIW that currently doesn't allow Procs, it gives `<internal:ractor>:828:in 'Ractor.make_shareable': allocator undefined for Proc (TypeError)`. I think the only other way, and I think it would be a far better way would be to not support making Procs shareable with `Ractor.make_shareable`. Instead it could be some new method like `isolated { ... }` or `Proc.isolated { ... }` or `Proc.snapshot_outer_variables { ... }` or so, only accepting a literal block (to avoid mutating/breaking an existing block), and that would snapshot outer variables (or require no outer variables like Ractor.new's block, or maybe even do `Ractor.make_shareable(copy: true)` on outer variables) and possibly also set `self` since that's anyway needed. That would make such blocks with different semantics explicit, which would fix the problem of breaking the intention of who wrote that block and whoever read that code, expecting normal Ruby block semantics, which includes seeing updated outer variables. Related: #21033 https://bugs.ruby-lang.org/issues/18243#note-5 Extracted from https://bugs.ruby-lang.org/issues/21033#note-14 -- https://bugs.ruby-lang.org/

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[ruby-core:117216] [Ruby master Bug#20346] FiberScheduler.unblock not called by Thread#join when Thread body contains Ractor.take
by forthoney (Seong-Heon Jung) 21 Aug '25

21 Aug '25

Issue #20346 has been reported by forthoney (Seong-Heon Jung). ---------------------------------------- Bug #20346: FiberScheduler.unblock not called by Thread#join when Thread body contains Ractor.take https://bugs.ruby-lang.org/issues/20346 * Author: forthoney (Seong-Heon Jung) * Status: Open * Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN ---------------------------------------- When using a `Ractor.take` inside a different thread, `Thread#join` on the thread running `Ractor.take` fails to call `FiberScheduler.unblock`. The below code can replicate this behavior ```ruby require "async" class RactorWrapper def initialize @ractor = Ractor.new do Ractor.recv # Ractor doesn't start until explicitly told to # Do some calculations fib = ->(x) { x < 2 ? 1 : fib.call(x - 1) + fib.call(x - 2) } fib.call(20) end end def take_async @ractor.send(nil) Thread.new { @ractor.take }.join.value end end Async do |task| 10000.times do |i| task.async do RactorWrapper.new.take_async puts i end end end ``` The above code deadlocks, and when we leave a debugging print statement inside of `Async`'s scheduler's `block` and `unblock` method, we can confirm that we only call `Scheduler.block`, and never `Scheduler.unblock` -- https://bugs.ruby-lang.org/

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[ruby-core:112206] [Ruby master Bug#19407] 2 threads taking from current ractor will hang forever
by luke-gru (Luke Gruber) 21 Aug '25

21 Aug '25

Issue #19407 has been reported by luke-gru (Luke Gruber). ---------------------------------------- Bug #19407: 2 threads taking from current ractor will hang forever https://bugs.ruby-lang.org/issues/19407 * Author: luke-gru (Luke Gruber) * Status: Open * Priority: Normal * Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN ---------------------------------------- In the current implementation of Ractors, it's possible to `take` from the current ractor. This could be useful when co-ordinating threads: ```ruby t = Thread.new do obj = Ractor.current.take p obj # do some work with obj end t0 = Thread.new do obj = Ractor.current.take p obj # do some work with obj end Ractor.yield :go ``` However it hangs forever: ```ruby t = Thread.new do obj = Ractor.current.take p obj end t0 = Thread.new do obj = Ractor.current.take p obj end sleep 0.5 ``` Should "self-take" be disabled, or was it designed to allow it but this is just a bug? -- https://bugs.ruby-lang.org/

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[ruby-core:115438] [Ruby master Misc#20013] Travis CI status
by jaruga (Jun Aruga) 15 Aug '25

15 Aug '25

Issue #20013 has been reported by jaruga (Jun Aruga). ---------------------------------------- Misc #20013: Travis CI status https://bugs.ruby-lang.org/issues/20013 * Author: jaruga (Jun Aruga) * Status: Open * Priority: Normal ---------------------------------------- I would like to use this ticket to manage our activities to report Travis CI status. Because there is Travis CI status page provided by Travis CI. However, even when the page shows ok, I actually see infra issues. https://www.traviscistatus.com/ I would share my activities and report the Travis CI status on the ticket. The ticket's status is not closed until we stop using Travis CI. The easiest option to fix the Travis infra issue is to email Travis CI support `support _AT_ travis-ci.com`. You can check [this ruby/ruby Travis CI wiki page](https://github.com/ruby/ruby/wiki/CI-Servers#travis-ci) for details. -- https://bugs.ruby-lang.org/

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[ruby-core:111789] [Ruby master Feature#19333] Setting (Fiber Local|Thread Local|Fiber Storage) to nil should delete value in order to avoid memory leaks.
by ioquatix (Samuel Williams) 07 Aug '25

07 Aug '25

Issue #19333 has been reported by ioquatix (Samuel Williams). ---------------------------------------- Feature #19333: Setting (Fiber Local|Thread Local|Fiber Storage) to nil should delete value in order to avoid memory leaks. https://bugs.ruby-lang.org/issues/19333 * Author: ioquatix (Samuel Williams) * Status: Open * Priority: Normal ---------------------------------------- As it stands, Fiber Locals, Thread Locals and Fiber Storage have no way of deleting key-value associations. ```ruby 100.times do |i| name = :"variable-#{i}" Thread.current[name] = 10 end ``` Because of this, dynamically generated associations can leak over time. This is worse for things like Threads that might be pooled (or maybe an argument against user-space pooling). In any case, having a way to delete those associations would allow application code to at least delete the associations when they no longer make sense. I propose that assigning `nil` to "locals" or "storage" should effectively delete them. e.g. ```ruby 100.times do |i| name = :"variable-#{i}" Thread.current[name] = 10 Thread.current[name] = nil # delete association end ``` A more invasive alternative would be to define new interfaces like `Thread::Local`, `Fiber::Local` and `Fiber::Storage::Local` (or something) which correctly clean up on GC. -- https://bugs.ruby-lang.org/

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[ruby-core:114590] [Ruby master Bug#19857] Eval coverage is reset after each `eval`.
by ioquatix (Samuel Williams) 06 Aug '25

06 Aug '25

Issue #19857 has been reported by ioquatix (Samuel Williams). ---------------------------------------- Bug #19857: Eval coverage is reset after each `eval`. https://bugs.ruby-lang.org/issues/19857 * Author: ioquatix (Samuel Williams) * Status: Open * Priority: Normal * Assignee: ioquatix (Samuel Williams) * Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN ---------------------------------------- It seems like `eval` based coverage is reset every time eval is invoked. ```ruby #!/usr/bin/env ruby require 'coverage' def measure(flag) c = Class.new c.class_eval(<<~RUBY, "foo.rb", 1) def foo(flag) if flag puts "foo" else puts "bar" end end RUBY return c.new.foo(flag) end Coverage.start(lines: true, eval: true) # Depending on the order of these two operations, different computation is calculated, because the evaluation of the code is considered different, even if the content/path is the same. measure(false) measure(true) p Coverage.result ``` Further investigation is required. -- https://bugs.ruby-lang.org/

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[ruby-core:119401] [Ruby master Bug#20776] [PRISM] Pattern matching syntax error message
by nobu (Nobuyoshi Nakada) 29 Jul '25

29 Jul '25

Issue #20776 has been reported by nobu (Nobuyoshi Nakada). ---------------------------------------- Bug #20776: [PRISM] Pattern matching syntax error message https://bugs.ruby-lang.org/issues/20776 * Author: nobu (Nobuyoshi Nakada) * Status: Open * Backport: 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN ---------------------------------------- Syntax error is fine, but is really expecting end-of-input there? ``` $ ruby -v -e '1 => $g' ruby 3.4.0dev (2024-10-01T14:59:58Z master 169a5ee99e) +PRISM [arm64-darwin23] -e:1: warning: possibly useless use of a variable in void context -e: -e:1: syntax errors found (SyntaxError) > 1 | 1 => $g | ^~ unexpected global variable, expecting end-of-input | ^~ expected a pattern expression after `=>` 2 | ``` And the line 2 is **not** in the input. -- https://bugs.ruby-lang.org/

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[ruby-core:120617] [Ruby master Feature#21028] Method for finding why an object isn't Ractor shareable
by tenderlovemaking (Aaron Patterson) 26 Jul '25

26 Jul '25

Issue #21028 has been reported by tenderlovemaking (Aaron Patterson). ---------------------------------------- Feature #21028: Method for finding why an object isn't Ractor shareable https://bugs.ruby-lang.org/issues/21028 * Author: tenderlovemaking (Aaron Patterson) * Status: Open ---------------------------------------- `Ractor.shareable?` is easy to use, but if it returns false I would like to be able to figure out what object is causing the data structure to _not_ be Ractor shareable. The context is that I'm trying to make some complex data structures in Rails deeply frozen. If they are deeply frozen they _should_ be Ractor shareable, but `Ractor.shareable?` is returning `false` and it's hard for me to figure out _why_. I would like a method that would either return all unshareable references, or a method that takes a block and unshareable references are yielded to the block. A method like `Ractor.unshareable_references?` or maybe `Ractor.shareable?(obj) { |not_shareable_obj| }` would be very helpful for discovering why an object is not shareable. Thanks! -- https://bugs.ruby-lang.org/

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[ruby-core:115422] [Ruby master Bug#20009] Marshal.load raises exception when load dumped class include non-ASCII
by ippachi (Kazuya Hatanaka) 19 Jul '25

19 Jul '25

Issue #20009 has been reported by ippachi (Kazuya Hatanaka). ---------------------------------------- Bug #20009: Marshal.load raises exception when load dumped class include non-ASCII https://bugs.ruby-lang.org/issues/20009 * Author: ippachi (Kazuya Hatanaka) * Status: Open * Priority: Normal * ruby -v: ruby 3.2.2 (2023-03-30 revision e51014f9c0) [arm64-darwin22] * Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN ---------------------------------------- ## Reproduction code ```ruby class Cクラス; end Marshal.load(Marshal.dump(Cクラス)) ``` ## Actual result ``` <internal:marshal>:34:in `load': undefined class/module C\xE3\x82\xAF\xE3\x83\xA9\xE3\x82\xB9 (ArgumentError) from marshal.rb:2:in `<main>' ``` ## Expected result Returns `Cクラス` ## Impacted area An exception is raised in Rails under the following conditions * minitest is used with default settings * Parallel execution with parallelize * test class names contain non-ASCII characters The default parallelization uses DRb, and Marshal is used inside DRb. ## Other After trying various things, I thought I could fix it by making `rb_path_to_class` support strings containing non-ASCII characters, but I couldn't find anything more than that. -- https://bugs.ruby-lang.org/

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[ruby-core:120579] [Ruby master Feature#21020] Sync sig directory for prism of default gem.
by ksss (Yuki Kurihara) 18 Jul '25

18 Jul '25

Issue #21020 has been reported by ksss (Yuki Kurihara). ---------------------------------------- Feature #21020: Sync sig directory for prism of default gem. https://bugs.ruby-lang.org/issues/21020 * Author: ksss (Yuki Kurihara) * Status: Open ---------------------------------------- Currently, the type signatures (RBS) for the default gem is not available. **Prism** is the only default gem with type signatures, but this number is expected to increase in the future. As a first step to resolving this issue, I propose including the `sig` directory of Prism as a default gem in the synchronization process. PR: https://github.com/ruby/ruby/pull/12541 -- https://bugs.ruby-lang.org/

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