2018-07-29 23:41 GMT+02:00 Jeroen Demeyer J.Demeyer@ugent.be:
For example, you mention that you want to make Py_INCREF() a function call instead of a macro. But since Py_INCREF is very common, I would guess that this would make performance worse (not by much maybe but surely measurable).
For the very specific case of Py_INCREF(), yes, I agree that performance is an issue. But I don't see how I would hide completely the PyObject structure without converting Py_INCREF() macro with a function call. (I have reasons to want to hide everything, explained in the project.)
The open question is if the cost of using function calls for Py_INCREF/DECREF versus the benefit of having the ability to modify deeply CPython internals.
I'm not sure that it's worth to bet at this point, it's too early, and we can decide that later. Moreover, it's also possible to keep Py_INCREF() as a macro in the "backward compatible" mode, but require a function call in the mode which hides all implementation details (the one where you can experiment deep CPython internals changes).