Issue #19254 has been updated by alanwu (Alan Wu). I agree with mame that the test is highly questionable. The GC does not guarantee collection for all semantically unreachable objects since it's not exact. Because we scan the native stack for conservative marking, changes in code generation could spill different objects to the native and keep them alive. This is probably what we're seeing through the combination of building YJIT + LTO, but not enabling YJIT at runtime. We could take a heap dump (`ObjectSpace.dump_all`) and verify that indeed the objects are kept alive through the machine context, but beyond that, I don't think there is much to do here. ---------------------------------------- Bug #19254: Enabling YJIT configuration option breaks rspec-core test suite https://bugs.ruby-lang.org/issues/19254#change-101198 * Author: vo.x (Vit Ondruch) * Status: Feedback * Priority: Normal * ruby -v: ruby 3.2.0dev (2022-12-23 master c5eefb7f37) [x86_64-linux] * Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN ---------------------------------------- In preparation for Ruby 3.2, we have enabled YJIT in Fedora: https://src.fedoraproject.org/rpms/ruby/c/3c1be9f9c2c1d8679eebb9a185fefa15ba... Since that moment, rspec-core test suite started to fail (see the attached log for all details): ~~~ ... snip ... 1) RSpec::Core::Example#run memory leaks, see GH-321, GH-1921 releases references to the examples / their ivars Failure/Error: expect(get_all.call).to eq opts.fetch(:post_gc) expected: [] got: ["after_all", "before_all"] (compared using ==) # ./spec/rspec/core/example_spec.rb:469:in `expect_gc' # ./spec/rspec/core/example_spec.rb:492:in `block (4 levels) in <top (required)>' # ./spec/support/sandboxing.rb:16:in `block (3 levels) in <top (required)>' # ./spec/support/sandboxing.rb:7:in `block (2 levels) in <top (required)>' Finished in 8.98 seconds (files took 0.47612 seconds to load) 2209 examples, 1 failure, 4 pending ~~~ Please note that the YJIT was not enabled during runtime, just the support was enabled. Disabling the YJIT supports makes the test case pass. [1]: https://download.copr.fedorainfracloud.org/results/vondruch/ruby-3.2/fedora-... [2]: https://copr.fedorainfracloud.org/coprs/vondruch/ruby-3.2/package/rubygem-rs... ---Files-------------------------------- builder-live.log.gz (28.7 KB) -- https://bugs.ruby-lang.org/