default features: make musl usable without feature test macros

the old behavior of exposing nothing except plain ISO C can be
obtained by defining __STRICT_ANSI__ or using a compiler option (such
as -std=c99) that predefines it. the new default featureset is POSIX
with XSI plus _BSD_SOURCE. any explicit feature test macros will
inhibit the default.

installation docs have also been updated to reflect this change.
This commit is contained in:
Rich Felker
2012-09-07 23:13:55 -04:00
parent 9f65796c35
commit c1a9658bd1
48 changed files with 102 additions and 129 deletions

View File

@ -1 +1,28 @@
#warning "features.h is bogus"
#ifndef _FEATURES_H
#define _FEATURES_H
#if !defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE) \
&& !defined(_XOPEN_SOURCE) && !defined(_GNU_SOURCE) \
&& !defined(_BSD_SOURCE) && !defined(__STRICT_ANSI__)
#define _BSD_SOURCE 1
#define _XOPEN_SOURCE 700
#endif
#if __STDC_VERSION__ >= 199901L
#define __restrict restrict
#elif !defined(__GNUC__)
#define __restrict
#endif
#if __STDC_VERSION__ >= 199901L || defined(__cplusplus)
#define __inline inline
#endif
#if __STDC_VERSION__ >= 201112L
#elif defined(__GNUC__)
#define _Noreturn __attribute__((__noreturn__))
#else
#define _Noreturn
#endif
#endif