diff options
| author | Warner Losh <imp@FreeBSD.org> | 2021-05-06 22:20:19 +0000 |
|---|---|---|
| committer | Warner Losh <imp@FreeBSD.org> | 2021-05-06 22:20:36 +0000 |
| commit | a709a4f0d4e0303eb40ea1b39b4bb35837800805 (patch) | |
| tree | f190337ec28bce1e0e466a5536c58ef10cb52baa | |
| parent | 6d6cca363392943689204f920fa2da9226e42056 (diff) | |
headers: Implement _ISOC11_SOURCES macro when __POSIX_C_SOURCE defined
When _ISOC11_SOURCES is defined for glibc at the same time
__POSIX_C_SOURCE is defined, it extends the __POSIX_C_SOURCE definition
by exaclty what C11 adds to the spec for each system header. We follow
both OpenBSD's and glibc's convention by also C11 or higher compliation
mode is selected.
The Open Group is working on issuing a new version of the POSIX standard
that will realign the standard from C99 to a newer version of C. This
commit is a stop-gap measure for greater compatibility until that
environment has been standardized.
Reviewed by: brooks@, arichards@, Olivier Certne
(comments tweaked before commit)
PR: 255290
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D29902
| -rw-r--r-- | sys/sys/cdefs.h | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/sys/sys/cdefs.h b/sys/sys/cdefs.h index ff461db9ec2e..309b2a4004a6 100644 --- a/sys/sys/cdefs.h +++ b/sys/sys/cdefs.h @@ -718,6 +718,17 @@ #define __POSIX_VISIBLE 198808 #define __ISO_C_VISIBLE 0 #endif /* _POSIX_C_SOURCE */ +/* + * Both glibc and OpenBSD enable c11 features when _ISOC11_SOURCE is defined, or + * when compiling with -stdc=c11. A strict reading of the standard would suggest + * doing it only for the former. However, a strict reading also requires C99 + * mode only, so building with C11 is already undefined. Follow glibc's and + * OpenBSD's lead for this non-standard configuration for maximum compatibility. + */ +#if _ISOC11_SOURCE || (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) +#undef __ISO_C_VISIBLE +#define __ISO_C_VISIBLE 2011 +#endif #else /*- * Deal with _ANSI_SOURCE: |