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[3.15] gh-159538: Fix deep chain leak in test_deeply_dotted_name (GH-159576) - #159609
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…onGH-159576) test_deeply_dotted_name() builds a 10,000-deep chain of lazy import placeholders in a thread with a 256 KiB C stack. Freeing the chain there defers most deallocations to the trashcan, which only drains them once the stack margin recovers. With a stack that small the margin never does, so the deferred objects were leaked when the thread exited, which -R reports as a reference leak on platforms with larger frames such as PPC64LE. Clear the namespace in a cleanup, which runs on the main thread. (cherry picked from commit c84d4b5) Co-authored-by: Brittany Reynoso <breynoso@meta.com>
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test_deeply_dotted_name() builds a 10,000-deep chain of lazy import
placeholders in a thread with a 256 KiB C stack. Freeing the chain
there defers most deallocations to the trashcan, which only drains them
once the stack margin recovers. With a stack that small the margin
never does, so the deferred objects were leaked when the thread exited,
which -R reports as a reference leak on platforms with larger frames
such as PPC64LE.
Clear the namespace in a cleanup, which runs on the main thread.
(cherry picked from commit c84d4b5)
Co-authored-by: Brittany Reynoso breynoso@meta.com
test_lazy_import.test_deeply_dotted_name()leaks 19,650 references on PPC64LE CentOS9 #159538