diff --git a/Include/pymacro.h b/Include/pymacro.h index e37cda44c5e..342d2a7b844 100644 --- a/Include/pymacro.h +++ b/Include/pymacro.h @@ -3,20 +3,23 @@ // gh-91782: On FreeBSD 12, if the _POSIX_C_SOURCE and _XOPEN_SOURCE macros are // defined, disables C11 support and does not define -// the static_assert() macro. Define the static_assert() macro in Python until -// suports C11: +// the static_assert() macro. // https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=255290 -#if defined(__FreeBSD__) && !defined(static_assert) -# define static_assert _Static_assert -#endif - -// static_assert is defined in glibc from version 2.16. Before it requires -// compiler support (gcc >= 4.6) and is called _Static_assert. -// In C++ 11 static_assert is a keyword, redefining is undefined behaviour. -#if (defined(__GLIBC__) \ - && (__GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ <= 16)) \ - && !(defined(__cplusplus) && __cplusplus >= 201103L) \ - && !defined(static_assert)) +// +// macOS <= 10.10 doesn't define static_assert in assert.h at all despite +// having C11 compiler support. +// +// static_assert is defined in glibc from version 2.16. Compiler support for +// the C11 _Static_assert keyword is in gcc >= 4.6. +// +// MSVC makes static_assert a keyword in C11-17, contrary to the standards. +// +// In C++11 and C2x, static_assert is a keyword, redefining is undefined +// behaviour. So only define if building as C (if __STDC_VERSION__ is defined), +// not C++, and only for C11-17. +#if !defined(static_assert) && (defined(__GNUC__) || defined(__clang__)) \ + && defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L \ + && __STDC_VERSION__ <= 201710L # define static_assert _Static_assert #endif diff --git a/Misc/NEWS.d/next/Build/2023-02-11-05-31-05.gh-issue-99069.X4LDvY.rst b/Misc/NEWS.d/next/Build/2023-02-11-05-31-05.gh-issue-99069.X4LDvY.rst new file mode 100644 index 00000000000..ae9b4d59ca8 --- /dev/null +++ b/Misc/NEWS.d/next/Build/2023-02-11-05-31-05.gh-issue-99069.X4LDvY.rst @@ -0,0 +1 @@ +Extended workaround defining ``static_assert`` when missing from the libc headers to all clang and gcc builds. In particular, this fixes building on macOS <= 10.10.