gh-135228: Create __dict__ and __weakref__ descriptors for object #136966
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…ke the original class collectible An interesting hack, but more localized in scope than python#135230. This may be a breaking change if people intentionally keep the original class around when using `@dataclass(slots=True)`, and then use `__dict__` or `__weakref__` on the original class.
| @@ -4038,22 +4038,25 @@ subtype_getweakref(PyObject *obj, void *context) | |||
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| /* Three variants on the subtype_getsets list. */ | |||
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| static char subtype_getset_dict_name[] = "__dict__"; | |||
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Please add a comment explaining why this is not inlined and is not const.
| // Hack: dict and weakref descriptors are created for `object`, | ||
| // rather than this specific type. | ||
| // We identify their PyGetSetDef by pointer equality on name. | ||
| if (gsp->name == subtype_getset_dict_name |
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Can we compare PyGetSetDef pointers? gsp == &subtype_getsets_full[0]
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I can polish this, but I think it'd be better to target 3.15, and follow through a bit more. |
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Here's another possible way to solve #135228:
The
__dict__and__weakref__descriptors don't really need to hold a strong reference to "their" type; they are generic and could be created forobjectinstead.Here's a proof of concept. A cleaner way to do this would be creating the descriptor objects once and caching them in the interpreter state.
This does involve a behaviour change -- before:
After: