Sporadic test failure in TestThread#test_thread_join_in_trap

[jcharaoui]

Running the JRuby 9.4.3.0 mri-core testsuite on Debian unstable (OpenJDK 17.0.9), I've been encountering intermittent failures with this test:

  1) Failure:
TestThread#test_thread_join_in_trap [/tmp/autopkgtest-lxc.035dzmv8/downtmp/autopkgtest_tmp/test/mri/ruby/test_thread.rb:997]:
assert_separately failed
pid 27166 exit 130

[jcharaoui]

I looked a bit into it and it seems #4956 was filed to track this exact (or very similar) issue, and that test was then added to exclusions in e2206af

However the exclusion was removed in b0862e6, perhaps unintentionally.

[jcharaoui]

I'll also note that I also tried to reproduce the issue by limiting test runs to only run tests from test/mri/ruby/test_thread.rb, rather than the full mri-core testsuite, and under these conditions I've not encountered the issue. Only when running mri-core fully (so far, at least).