PyOS_CheckStack docs currently say it's only available when USE_STACKCHECK is defined (currently on Windows using the Microsoft Visual C++ compiler).

However, according to the code, it's only available on 32-bit Windows, and has some other restrictions that might or might not be relevant today.

The note should not imply that all MSVC Windows builds have the macro. It should say something like “certain versions of Windows” or “Windows for certain platforms”.