gh-135909: Assert incoming refcnt != 0 for the free threaded GC.#136009
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colesbury merged 1 commit intopython:mainfrom Jul 15, 2025
Merged
gh-135909: Assert incoming refcnt != 0 for the free threaded GC.#136009colesbury merged 1 commit intopython:mainfrom
colesbury merged 1 commit intopython:mainfrom
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This is to catch out double deallocation bugs. Likely from a faulty .tp_dealloc allowing the GC to run before the object is untracked. This assert matches the one added to the GIL build, in 780c497. The call to validate_refcounts was moved up to start of the GC because queue_untracked_obj_decref() creates it own zero reference count garbage.
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| // the object. The likely cause for hitting this is a faulty .tp_dealloc. | ||
| // Also see the comment in `update_refs()`. | ||
| _PyObject_ASSERT_WITH_MSG(op, Py_REFCNT(op) > 0, | ||
| "tracked objects must have a reference count > 0"); |
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If we're trying to mimick the default GC, let's use the same error message:
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| "tracked objects must have a reference count > 0"); | |
| "refcount is too small"); |
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…GC (pythonGH-136009) This helps catch double deallocation bugs and is similar to the assertion in the GIL-enabled build. The call to `validate_refcounts` is moved up to start of the GC because `queue_untracked_obj_decref()` creates it own zero reference count garbage.
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…GC (pythonGH-136009) This helps catch double deallocation bugs and is similar to the assertion in the GIL-enabled build. The call to `validate_refcounts` is moved up to start of the GC because `queue_untracked_obj_decref()` creates it own zero reference count garbage.
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This is to catch out double deallocation bugs. Likely from a faulty .tp_dealloc allowing the GC to run before the object is untracked.
This assert matches the one added to the GIL build, in 780c497. The call to validate_refcounts was moved up to start of the GC because queue_untracked_obj_decref() creates it own zero reference count garbage.