svn commit: r271012 - in head: include sys/sys

[Ed Schouten]

Author: ed
Date: Wed Sep  3 09:35:38 2014
New Revision: 271012
URL: http://svnweb.freebsd.org/changeset/base/271012

Log:
  Leave the C11 keywords alone when we have a recent version of GCC.
  
  As GCC also gained support for the C11 keywords over time, we can patch
  up <sys/cdefs.h> to not define these anymore. This has the advantage
  that error messages for static assertions are printed natively and that
  _Alignas() will work with even a type outside of C11 mode.
  
  All C11 keywords are supported with GCC 4.7 and higher, with the
  exception of _Thread_local and _Generic. These are only supported as of
  GCC 4.9.

Modified:
  head/include/tgmath.h
  head/sys/sys/cdefs.h

Modified: head/include/tgmath.h
==============================================================================
--- head/include/tgmath.h	Wed Sep  3 09:05:37 2014	(r271011)
+++ head/include/tgmath.h	Wed Sep  3 09:35:38 2014	(r271012)
@@ -61,7 +61,7 @@
  */
 
 #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) || \
-    __has_extension(c_generic_selections)
+    __has_extension(c_generic_selections) || __GNUC_PREREQ__(4, 9)
 #define	__tg_generic(x, cfnl, cfn, cfnf, fnl, fn, fnf)			\
 	_Generic(x,							\
 		long double _Complex: cfnl,				\

Modified: head/sys/sys/cdefs.h
==============================================================================
--- head/sys/sys/cdefs.h	Wed Sep  3 09:05:37 2014	(r271011)
+++ head/sys/sys/cdefs.h	Wed Sep  3 09:35:38 2014	(r271012)
@@ -254,7 +254,7 @@
 
 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L
 
-#if !__has_extension(c_alignas)
+#if !__has_extension(c_alignas) && !__GNUC_PREREQ__(4, 7)
 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
     __has_extension(cxx_alignas)
 #define	_Alignas(x)		alignas(x)
@@ -264,11 +264,13 @@
 #endif
 #endif
 
+#if !__GNUC_PREREQ__(4, 7)
 #if defined(__cplusplus) && __cplusplus >= 201103L
 #define	_Alignof(x)		alignof(x)
 #else
 #define	_Alignof(x)		__alignof(x)
 #endif
+#endif
 
 #if !__has_extension(c_atomic) && !__has_extension(cxx_atomic)
 /*
@@ -278,13 +280,15 @@
 #define	_Atomic(T)		struct { T volatile __val; }
 #endif
 
+#if !__GNUC_PREREQ__(4, 7)
 #if defined(__cplusplus) && __cplusplus >= 201103L
 #define	_Noreturn		[[noreturn]]
 #else
 #define	_Noreturn		__dead2
 #endif
+#endif
 
-#if !__has_extension(c_static_assert)
+#if !__has_extension(c_static_assert) && !__GNUC_PREREQ__(4, 7)
 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
     __has_extension(cxx_static_assert)
 #define	_Static_assert(x, y)	static_assert(x, y)
@@ -297,7 +301,7 @@
 #endif
 #endif
 
-#if !__has_extension(c_thread_local)
+#if !__has_extension(c_thread_local) && !__GNUC_PREREQ__(4, 9)
 /*
  * XXX: Some compilers (Clang 3.3, GCC 4.7) falsely announce C++11 mode
  * without actually supporting the thread_local keyword. Don't check for
@@ -322,7 +326,8 @@
  * distinguish multiple cases.
  */
 
-#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
+#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) || \
+    __has_extension(c_generic_selections) || __GNUC_PREREQ__(4, 9)
 #define	__generic(expr, t, yes, no)					\
 	_Generic(expr, t: yes, default: no)
 #elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus)