`pyport.h`: use `__STDC_VERSION__ >= 202311L` instead of `__STDC_VERSION__ > 201710L`

[anthony-tuininga]

Bug report

Bug description:

This code in pyport.h neds to be updated:

// Static inline functions should use _Py_NULL rather than using directly NULL
// to prevent C++ compiler warnings. On C23 and newer and on C++11 and newer,
// _Py_NULL is defined as nullptr.
#if !defined(_MSC_VER) && \
    ((defined (__STDC_VERSION__) && __STDC_VERSION__ > 201710L) \
        || (defined(__cplusplus) && __cplusplus >= 201103))
#  define _Py_NULL nullptr
#else
#  define _Py_NULL NULL
#endif

It is using the wrong definition of C23 which should be 202311L as noted in the Wiki page referenced in this commit.

CPython versions tested on:

3.13

Operating systems tested on:

Linux

Linked PRs

• gh-137058: use __STDC_VERSION__ >= 202311L instead of __STDC_VERSION__ > 201710L #137127
• [3.14] gh-137058: Sync _Py_NULL macro with the main branch #137409

[brianschubert]

The check is > 201710L, not >= 201710L, so I think it works as intended: it only passes for editions later than C17, i.e. C23 or later. The commit dates to 2023-08, so I imagine it was done this way since 202311L wasn't yet established (and wouldn't be until sometime after 2023-11).

cc @vstinner

[anthony-tuininga]

Yes, at the time this was committed it was reasonable to use. It should be updated now to use the official label.

[abdoulrasheed]

Can i pick this? @anthony-tuininga @brianschubert

[abdoulrasheed]

@brianschubert — I’ve opened a PR and would appreciate it if you could take a look when you have the time. Thanks!

[picnixz]

Thanks for the report & fix! I'm leaving it open until we decide whether to backport this to 3.14 to help future maintenance (see #137127 (comment))