diff options
Diffstat (limited to 'include/features.h')
-rw-r--r-- | include/features.h | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/include/features.h b/include/features.h index 56d1c571b6..404014115a 100644 --- a/include/features.h +++ b/include/features.h @@ -24,6 +24,7 @@ __STRICT_ANSI__ ISO Standard C. _ISOC99_SOURCE Extensions to ISO C89 from ISO C99. _ISOC11_SOURCE Extensions to ISO C99 from ISO C11. + __STDC_WANT_LIB_EXT2__ Extensions to ISO C99 from TR 27431-2:2010. _POSIX_SOURCE IEEE Std 1003.1. _POSIX_C_SOURCE If ==1, like _POSIX_SOURCE; if >=2 add IEEE Std 1003.2; if >=199309L, add IEEE Std 1003.1b-1993; @@ -58,6 +59,10 @@ These are defined by this file and are used by the header files to decide what to declare or define: + __GLIBC_USE (F) Define things from feature set F. This is defined + to 1 or 0; the subsequent macros are either defined + or undefined, and those tests should be moved to + __GLIBC_USE. __USE_ISOC11 Define ISO C11 things. __USE_ISOC99 Define ISO C99 things. __USE_ISOC95 Define ISO C90 AMD1 (C95) things. @@ -90,7 +95,14 @@ explicitly undefined if they are not explicitly defined. Feature-test macros that are not defined by the user or compiler but are implied by the other feature-test macros defined (or by the - lack of any definitions) are defined by the file. */ + lack of any definitions) are defined by the file. + + ISO C feature test macros depend on the definition of the macro + when an affected header is included, not when the first system + header is included, and so they are handled in + <bits/libc-header-start.h>, which does not have a multiple include + guard. Feature test macros that can be handled from the first + system header included are handled here. */ /* Undefine everything, so we get a clean slate. */ @@ -139,6 +151,9 @@ # define __GNUC_PREREQ(maj, min) 0 #endif +/* Whether to use feature set F. */ +#define __GLIBC_USE(F) __GLIBC_USE_ ## F + /* _BSD_SOURCE and _SVID_SOURCE are deprecated aliases for _DEFAULT_SOURCE. If _DEFAULT_SOURCE is present we do not issue a warning; the expectation is that the source is being |