aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--ChangeLog6
-rw-r--r--include/features.h19
-rw-r--r--misc/sys/cdefs.h22
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.