dataclasses: implicitly defined __dict__ and __weakref__ slots of inherited classes are ignored. #105866
Description
Bug report
The weakref slot is redefined when inherited from a class which didn't specify slots at all (and thus has a dict and weakref slots).
from dataclasses import dataclass
class A:
pass
@dataclass(slots=True, weakref_slot=True)
class B(A):
pass
gives the following error:
TypeError: __weakref__ slot disallowed: either we already got one, or __itemsize__ != 0