[3.13] gh-132942: Fix races in type lookup cache

[nascheme]

Two races related to the type lookup cache, when used in the free-threaded build. This caused test_opcache to sometimes fail (as well as other hard to re-produce failures).

• Issue: test_opcache fails randomly (failure or crash) #132942

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot aarch64 Fedora Stable Clang 3.13 (tier-2) has failed when building commit ca46ec8.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/1456/builds/695) and take a look at the build logs.
4. Check if the failure is related to this commit (ca46ec8) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/1456/builds/695

Failed tests:

• test_interpreters

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last): File "/home/buildbot/buildarea/3.13.cstratak-fedora-stable-aarch64.clang/build/Lib/threading.py", line 1041, in _bootstrap_innerself.run() ~~~~~~~~^^ File "/home/buildbot/buildarea/3.13.cstratak-fedora-stable-aarch64.clang/build/Lib/threading.py", line 992, in runself._target(*self._args, **self._kwargs) ~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/home/buildbot/buildarea/3.13.cstratak-fedora-stable-aarch64.clang/build/Lib/test/test_interpreters/test_stress.py", line 47, in run interp = interpreters.create() File "/home/buildbot/buildarea/3.13.cstratak-fedora-stable-aarch64.clang/build/Lib/test/support/interpreters/__init__.py", line 76, in createid= _interpreters.create(reqrefs=True) interpreters.InterpreterError: interpreter creation failed k Traceback (most recent call last): File "/home/buildbot/buildarea/3.13.cstratak-fedora-stable-aarch64.clang/build/Lib/threading.py", line 1041, in _bootstrap_innerself.run() ~~~~~~~~^^ File "/home/buildbot/buildarea/3.13.cstratak-fedora-stable-aarch64.clang/build/Lib/threading.py", line 992, in runself._target(*self._args, **self._kwargs) ~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/home/buildbot/buildarea/3.13.cstratak-fedora-stable-aarch64.clang/build/Lib/test/test_interpreters/test_stress.py", line 30, in task interp = interpreters.create() File "/home/buildbot/buildarea/3.13.cstratak-fedora-stable-aarch64.clang/build/Lib/test/support/interpreters/__init__.py", line 76, in createid= _interpreters.create(reqrefs=True) interpreters.InterpreterError: interpreter creation failed k 

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot s390x RHEL9 Refleaks 3.13 (tier-3) has failed when building commit ca46ec8.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/1575/builds/743) and take a look at the build logs.
4. Check if the failure is related to this commit (ca46ec8) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/1575/builds/743

Failed tests:

• test_descr

Failed subtests:

• test_type_lookup_mro_reference - test.test_descr.MiscTests.test_type_lookup_mro_reference

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last): File "/home/buildbot/buildarea/3.13.cstratak-rhel9-s390x.refleak/build/Lib/test/test_descr.py", line 5181, in test_type_lookup_mro_referenceself.assertEqual(X.mykey, 'from Base') ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^AssertionError: 'from Base2' != 'from Base' - from Base2 ? - + from Base 

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot AMD64 RHEL8 Refleaks 3.13 (tier-1) has failed when building commit ca46ec8.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/1385/builds/834) and take a look at the build logs.
4. Check if the failure is related to this commit (ca46ec8) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/1385/builds/834

Failed tests:

• test_descr

Failed subtests:

• test_type_lookup_mro_reference - test.test_descr.MiscTests.test_type_lookup_mro_reference

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last): File "/home/buildbot/buildarea/3.13.cstratak-RHEL8-x86_64.refleak/build/Lib/test/test_descr.py", line 5181, in test_type_lookup_mro_referenceself.assertEqual(X.mykey, 'from Base') ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^AssertionError: 'from Base2' != 'from Base' - from Base2 ? - + from Base 

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot AMD64 FreeBSD Refleaks 3.13 (tier-3) has failed when building commit ca46ec8.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/1615/builds/703) and take a look at the build logs.
4. Check if the failure is related to this commit (ca46ec8) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/1615/builds/703

Failed tests:

• test_descr

Failed subtests:

• test_type_lookup_mro_reference - test.test_descr.MiscTests.test_type_lookup_mro_reference

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last): File "/buildbot/buildarea/3.13.ware-freebsd.refleak/build/Lib/test/test_descr.py", line 5181, in test_type_lookup_mro_referenceself.assertEqual(X.mykey, 'from Base') ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^AssertionError: 'from Base2' != 'from Base' - from Base2 ? - + from Base 

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot AMD64 Fedora Stable Refleaks 3.13 (tier-1) has failed when building commit ca46ec8.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/1471/builds/729) and take a look at the build logs.
4. Check if the failure is related to this commit (ca46ec8) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/1471/builds/729

Failed tests:

• test_descr

Failed subtests:

• test_type_lookup_mro_reference - test.test_descr.MiscTests.test_type_lookup_mro_reference

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last): File "/home/buildbot/buildarea/3.13.cstratak-fedora-stable-x86_64.refleak/build/Lib/test/test_descr.py", line 5181, in test_type_lookup_mro_referenceself.assertEqual(X.mykey, 'from Base') ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^AssertionError: 'from Base2' != 'from Base' - from Base2 ? - + from Base 

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot aarch64 Fedora Stable Refleaks 3.13 (tier-2) has failed when building commit ca46ec8.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/1512/builds/556) and take a look at the build logs.
4. Check if the failure is related to this commit (ca46ec8) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/1512/builds/556

Failed tests:

• test_descr

Failed subtests:

• test_python_calls_appear_in_the_stack_if_perf_activated - test.test_perf_profiler.TestPerfProfilerWithDwarf.test_python_calls_appear_in_the_stack_if_perf_activated
• test_type_lookup_mro_reference - test.test_descr.MiscTests.test_type_lookup_mro_reference

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last): File "/home/buildbot/buildarea/3.13.cstratak-fedora-stable-aarch64.refleak/build/Lib/test/test_descr.py", line 5181, in test_type_lookup_mro_referenceself.assertEqual(X.mykey, 'from Base') ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^AssertionError: 'from Base2' != 'from Base' - from Base2 ? - + from Base Traceback (most recent call last): File "/home/buildbot/buildarea/3.13.cstratak-fedora-stable-aarch64.refleak/build/Lib/test/test_perf_profiler.py", line 367, in test_python_calls_appear_in_the_stack_if_perf_activatedself.assertEqual(stderr, "") ~~~~~~~~~~~~~~~~^^^^^^^^^^^^AssertionError: 'Warning:\nProcessed 714 events and lost 3[34 chars]\n\n' != '' - Warning: - Processed 714 events and lost 3 chunks! - - Check IO/CPU overload! - 

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot aarch64 RHEL8 Refleaks 3.13 (tier-2) has failed when building commit ca46ec8.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/1445/builds/595) and take a look at the build logs.
4. Check if the failure is related to this commit (ca46ec8) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/1445/builds/595

Failed tests:

• test_descr

Failed subtests:

• test_type_lookup_mro_reference - test.test_descr.MiscTests.test_type_lookup_mro_reference

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last): File "/home/buildbot/buildarea/3.13.cstratak-RHEL8-aarch64.refleak/build/Lib/test/test_descr.py", line 5181, in test_type_lookup_mro_referenceself.assertEqual(X.mykey, 'from Base') ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^AssertionError: 'from Base2' != 'from Base' - from Base2 ? - + from Base 

[nascheme]

I believe this has revealed a bug in the unit test that the MRO cache bug was hidding. See gh-133122. The quick fix would be to just disable that unit test.

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot PPC64LE Fedora Stable Refleaks 3.13 (tier-2) has failed when building commit ca46ec8.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/1467/builds/549) and take a look at the build logs.
4. Check if the failure is related to this commit (ca46ec8) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/1467/builds/549

Failed tests:

• test_descr

Failed subtests:

• test_type_lookup_mro_reference - test.test_descr.MiscTests.test_type_lookup_mro_reference

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last): File "/home/buildbot/buildarea/3.13.cstratak-fedora-stable-ppc64le.refleak/build/Lib/test/test_descr.py", line 5181, in test_type_lookup_mro_referenceself.assertEqual(X.mykey, 'from Base') ~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^AssertionError: 'from Base2' != 'from Base' - from Base2 ? - + from Base