[3.14] gh-155109: Run tests exhausting the C stack with a limited C stack (GH-155120) - #155165
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serhiy-storchaka merged 1 commit intoAug 4, 2026
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…ack (pythonGH-155120) Add the @support.run_with_limited_c_stack() decorator which runs the test in a thread with a 8 MiB C stack, so that the outcome does not depend on RLIMIT_STACK. Use it in tests which recurse to a fixed depth -- @support.skip_if_huge_c_stack() failed to skip them with a 16 MiB stack. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> (cherry picked from commit ce5ae29)
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August 4, 2026 10:04
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Add the
@support.run_with_limited_c_stack(depth)decorator: it runs the test in a thread with an 8 MiB C stack, so that the outcome does not depend onRLIMIT_STACK. If the thread stack size cannot be limited, it falls back to the old behavior — run in the current thread and skip if the C stack is too large.Use it in tests which recurse to a fixed depth.
@support.skip_if_huge_c_stack()estimates the remaining stack in interpreter loop frames (~328 bytes), so it fails to skip tests which recurse with much smaller C frames (~100 bytes) — they fail with a 16 MiB stack. It is kept for tests with unbounded recursion and fortest_call.test_super_deep(), which needs a deep stack.(cherry picked from commit ce5ae29)
Co-authored-by: Serhiy Storchaka storchaka@gmail.com
skip_if_huge_c_stackunderestimates available C recursion depth #155109