Ruby Issue Tracking System

08/13/2026

05:17 AM Ruby Bug #18444: Trapped TSTP causes a locking deadlock in 3.0.3 onward

This issue can also be reproduced on the master branch. Since it is not specific to TSTP, it can be reproduced with any signal.
```
$ ./miniruby -ve 'Signal.trap(:TERM) { print "2\r"; sleep 0.01; exit(0) }; spawn("sleep 0.1; kill -TE... wanabe (_ wanabe)

08/11/2026

09:48 AM Ruby Bug #18804: Invalid line number for putnil instruction

Isn't this issue negligible at this point?
When using Prism—that is, by default—this issue does not arise.
```
$ ./miniruby -v ../a.rb
ruby 4.1.0dev (2026-08-02T09:00:37Z :detached: 63c7beb2ef) +PRISM [x86_64-linux]
== disasm: #<I... wanabe (_ wanabe)

08/10/2026

03:54 AM Ruby Bug #15599 (Closed): Mixing autoload and require causes deadlock and incomplete definition.

This issue was fixed between preview 2 and preview 3 of Ruby 3.3.0.
```
$ cat a.rb
class A
def a1() end
end
$ cat base.rb
1000.times do
fork do
autoload :A, './a'
t1 = Thread.new { raise if A.instance_methods(fal... wanabe (_ wanabe)

08/09/2026

11:42 AM Ruby Bug #15499: Breaking behavior on ruby 2.6: rb_thread_call_without_gvl doesn't invoke unblock_function when used on the main thread

It looks like it might be fixed with 1d4822a175a0dfccca8f252b0e757a1991bd54f9, but I'm not sure.
```
$ git checkout 1d4822a175a0dfccca8f252b0e757a1991bd54f9~; if make -j miniruby >/dev/null 2>&1; then ./miniruby -e 'Thread.new
{ Rac... wanabe (_ wanabe)

10:01 AM Ruby Bug #21206 (Closed): Segmentation fault on ISeq#to_binary

The issue has been fixed.
```
$ docker run -it -e ALL_RUBY_SINCE=4.0.0-preview2 ghcr.io/ruby/all-ruby /all-ruby/all-ruby -e 'RubyVM::InstructionSequence.compile_parsey("def f(g) = each {nil rescue g+it}").to_binary; p :ok'
ruby-4.0.... wanabe (_ wanabe)

08/02/2026

12:42 PM Ruby Bug #15598: Deadlock on mutual reference of autoloaded constants

This issue appears to have been corrected at https://github.com/ruby/ruby/commit/6fbc32b5d0da31535cccc0eca1853273313a0b52.
```
$ (git checkout 6fbc32b5d0da31535cccc0eca1853273313a0b52~; make -j miniruby) >/dev/null && ./miniruby -v b... wanabe (_ wanabe)

07/20/2026

10:35 AM Ruby Bug #19922 (Closed): ObjectSpace.dump_all in multiple threads in parallel causes SEGV

This issue was fixed in commit `3c63a01295b4219743b3d3e883fd4a4a616960a` and has not recurred since then.
Thank you.
```
$ git checkout 3c63a01295b4219743b3d3e883fd4a4a616960a6; make -j8 exts >/dev/null 2>&1 && ./ruby -v -I .ext/x86... wanabe (_ wanabe)

02/19/2025

11:05 PM Ruby Bug #21149 (Rejected): Strange behavior of ObjectSpace.each_object after Ractor.new

Thank you. I forgot to search existing issues before opening the ticket. Now I can see many related tickets:
- [Feature #17270] ObjectSpace.each_object should be restricted on multi-Ractors
- [Bug #17360] Objects disappear from Objec... wanabe (_ wanabe)

09:42 AM Ruby Bug #21149 (Rejected): Strange behavior of ObjectSpace.each_object after Ractor.new

I found the strange behavior of `ObjectSpace.each_object`.
It misses some objects after `Ractor.new`.
```
$ ruby -ve 'class Foo; end; foo = Foo.new; Ractor.new do buz = Foo.new end.take; bar = Foo.new; p [ObjectSpace.each_object(Foo... wanabe (_ wanabe)

02/02/2025

01:18 PM Ruby Feature #21109 (Closed): Want to clarify how $/ is handled in Ractor

I am often in trouble because `$/` is inaccessible in Ractor.
For example, `IO#readline` can't be called from non-main Ractor.
```
$ echo "foo"|ruby -e 'Ractor.new do p $stdin.readline end.take'
-e:1: warning: Ractor is experimenta... wanabe (_ wanabe)