[3.12] gh-109496: Detect Py_DECREF() after dealloc in debug mode (GH-109539) #109545
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…onGH-109539) On a Python built in debug mode, Py_DECREF() now calls _Py_NegativeRefcount() if the object is a dangling pointer to deallocated memory: memory filled with 0xDD "dead byte" by the debug hook on memory allocators. The fix is to check the reference count *before* checking for _Py_IsImmortal(). Add test_decref_freed_object() to test_capi.test_misc. (cherry picked from commit 0bb0d88) Co-authored-by: Victor Stinner <[email protected]>
This was referenced Sep 18, 2023
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On a Python built in debug mode, Py_DECREF() now calls
_Py_NegativeRefcount() if the object is a dangling pointer to
deallocated memory: memory filled with 0xDD "dead byte" by the debug
hook on memory allocators. The fix is to check the reference count
before checking for _Py_IsImmortal().
Add test_decref_freed_object() to test_capi.test_misc.
(cherry picked from commit 0bb0d88)
Co-authored-by: Victor Stinner [email protected]
Py_DECREFtwice does not result in error with debug build #109496