diff options
| -rw-r--r-- | ChangeLog | 6 | ||||
| -rw-r--r-- | include/features.h | 19 | ||||
| -rw-r--r-- | misc/sys/cdefs.h | 22 |
3 files changed, 42 insertions, 5 deletions
diff --git a/ChangeLog b/ChangeLog index bd751f26d0..ceb28b5c74 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2016-08-03 Zack Weinberg <zackw@panix.com> + + * include/features.h (__glibc_clang_prereq): New macro. + * misc/sys/cdefs.h (__glibc_clang_has_extension) + (__attribute_deprecated_msg__): New macros. + 2016-08-03 Joseph Myers <joseph@codesourcery.com> * bits/libc-header-start.h (__GLIBC_USE_IEC_60559_BFP_EXT): New diff --git a/include/features.h b/include/features.h index f2cd148fa4..554c5c888a 100644 --- a/include/features.h +++ b/include/features.h @@ -138,13 +138,13 @@ # define __KERNEL_STRICT_NAMES #endif -/* Convenience macros to test the versions of glibc and gcc. - Use them like this: +/* Convenience macro to test the version of gcc. + Use like this: #if __GNUC_PREREQ (2,8) ... code requiring gcc 2.8 or later ... #endif - Note - they won't work for gcc1 or glibc1, since the _MINOR macros - were not defined then. */ + Note: only works for GCC 2.0 and later, because __GNUC_MINOR__ was + added in 2.0. */ #if defined __GNUC__ && defined __GNUC_MINOR__ # define __GNUC_PREREQ(maj, min) \ ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min)) @@ -152,6 +152,17 @@ # define __GNUC_PREREQ(maj, min) 0 #endif +/* Similarly for clang. Features added to GCC after version 4.2 may + or may not also be available in clang, and clang's definitions of + __GNUC(_MINOR)__ are fixed at 4 and 2 respectively. Not all such + features can be queried via __has_extension/__has_feature. */ +#if defined __clang_major__ && defined __clang_minor__ +# define __glibc_clang_prereq(maj, min) \ + ((__clang_major__ << 16) + __clang_minor__ >= ((maj) << 16) + (min)) +#else +# define __glibc_clang_prereq(maj, min) 0 +#endif + /* Whether to use feature set F. */ #define __GLIBC_USE(F) __GLIBC_USE_ ## F diff --git a/misc/sys/cdefs.h b/misc/sys/cdefs.h index a3c2429b32..6e9b8403d7 100644 --- a/misc/sys/cdefs.h +++ b/misc/sys/cdefs.h @@ -77,6 +77,15 @@ #endif /* GCC. */ +/* Compilers that are not clang may object to + #if defined __clang__ && __has_extension(...) + even though they do not need to evaluate the right-hand side of the &&. */ +#if defined __clang__ && defined __has_extension +# define __glibc_clang_has_extension(ext) __has_extension (ext) +#else +# define __glibc_clang_has_extension(ext) 0 +#endif + /* These two macros are not used in glibc anymore. They are kept here only because some other projects expect the macros to be defined. */ #define __P(args) args @@ -249,13 +258,24 @@ # define __attribute_noinline__ /* Ignore */ #endif -/* gcc allows marking deprecated functions. */ +/* Since version 3.2, gcc allows marking deprecated functions. */ #if __GNUC_PREREQ (3,2) # define __attribute_deprecated__ __attribute__ ((__deprecated__)) #else # define __attribute_deprecated__ /* Ignore */ #endif +/* Since version 4.5, gcc also allows one to specify the message printed + when a deprecated function is used. clang claims to be gcc 4.2, but + may also support this feature. */ +#if __GNUC_PREREQ (4,5) || \ + __glibc_clang_has_extension (__attribute_deprecated_with_message__) +# define __attribute_deprecated_msg__(msg) \ + __attribute__ ((__deprecated__ (msg))) +#else +# define __attribute_deprecated_msg__(msg) __attribute_deprecated__ +#endif + /* At some point during the gcc 2.8 development the `format_arg' attribute for functions was introduced. We don't want to use it unconditionally (although this would be possible) since it generates warnings. |