gh-120600: Make Py_TYPE() opaque in limited C API 3.14 #120601
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In the limited C API 3.14 and newer, Py_TYPE() is now implemented as an opaque function call to hide implementation details.
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I don't understand your remark. Are you suggesting to reimplement Py_TYPE() on top of PyObject_Type()? Py_TYPE() returns a borrowed reference, PyObject_Type() returns a strong reference. |
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Py_TYPE was defined as a macro, it depends on the internal structure of PyObject. If you need to use the limited C API, use PyObject_Type() instead of Py_TYPE(). |
Py_TYPE() is very commonly used in C extensions. Having to switch to PyObject_Type() is a lot of work. I don't want to force C extensions maintainers to do that. I only want to hide the implementation details (access to It's not convenient to have to release a reference when using PyObject_Type(), compared to Py_TYPE(). |
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Has not C API returning a borrowed reference been frowned upon lately? Strictly speaking, Py_TYPE() is incompatible with Free Threading. If you want to use the limited C API, use PyObject_Type(). If you prefer performance and convenience, use Py_TYPE() and the GIL. |
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I don't get it. The stable ABI is guaranteed to be stable. Py_TYPE() is part of the stable ABI. I'm not asking to add it. Only to change its implementation. |
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Than what is the point of changing |
As written previously, I am trying to avoid accessing PyObject members directly. This change is part of this project, even if it doesn't disallow accessing PyObject members yet. |
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+1 from me. Even if we can't change the current version of the stable ABI, moving to functions makes sense.
Exposed structs are the one biggest issue with abi4; if there's ever a new version of a stable ABI, it probably won't have them.
It would be great if modules compiled for the next stable ABI are compatible with 3.14, and at the same time stay API-compatible.
Co-authored-by: Petr Viktorin <[email protected]>
…120601) In the limited C API 3.14 and newer, Py_TYPE() is now implemented as an opaque function call to hide implementation details.
…120601) In the limited C API 3.14 and newer, Py_TYPE() is now implemented as an opaque function call to hide implementation details.
…120601) In the limited C API 3.14 and newer, Py_TYPE() is now implemented as an opaque function call to hide implementation details.
…120601) In the limited C API 3.14 and newer, Py_TYPE() is now implemented as an opaque function call to hide implementation details.
In the limited C API 3.14 and newer, Py_TYPE() and Py_SET_TYPE() are now implemented as opaque function calls to hide implementation details.
📚 Documentation preview 📚: https://cpython-previews--120601.org.readthedocs.build/