In the C API, we have some functions that need to access state that is deleted by finalization. For example,PyGILState_Ensure accesses the gilstate, and that can be concurrently deallocated. In that specific case, I proposed#132510 as a fix, but really, we should have a better way to protect state against a finalizing interpreter. I'm not sure whether to categorize this as a bug or a feature.

I think the best way to do this is through a finalizing counter similar to howPEP-788 proposes preventing interpreter shutdown. So, for functions that don't require an attached thread state, we need something like:

intPySomething_Whatever(PyInterpreterState*interp){if (_PyInterpreterState_CriticalSection(interp)<0) {// Interpreter has finalizedreturn-1;    }/* Do critical operation */_PyInterpreterState_EndCriticalSection(interp);return0;}

Does this approach seem reasonable to everyone?

cc@ericsnowcurrently