_PyObject_StoreInstanceAttribute assertion fails in setattr after __dict__.clear() #117750
Description
Bug report
Bug description:
On current main (edit: debug build),
class C:
def __init__(self):
self.__dict__.clear()
obj = C()
obj.foo = Nonefails with:
python: Objects/dictobject.c:6704: _PyObject_StoreInstanceAttribute: Assertion 'dict->ma_values == values' failed.
CPython versions tested on:
CPython main branch
Operating systems tested on:
Linux
Notes
Originally reported here: https://discuss.python.org/t/python-3-12-3-and-3-13-0a6-released/50601/2