svn commit: r309258 - in stable: 10/include 10/sys/sys 11/include 11/sys/sys

[John Baldwin]

Author: jhb
Date: Mon Nov 28 18:36:37 2016
New Revision: 309258
URL: https://svnweb.freebsd.org/changeset/base/309258

Log:
  MFC 307756: Define max_align_t for C11.
  
  libc++'s stddef.h includes an existing definition of max_align_t for
  C++11, but it is only defined for C++, not for C.  In addition, GCC and
  clang both define an alternate version of max_align_t that uses a
  union of multiple types rather than a plain long double as in libc++.
  This adds a __max_align_t to <sys/_types.h> that matches the GCC and
  clang definition that is mapped to max_align_t in <stddef.h>.
  
  PR:		210890

Modified:
  stable/10/include/stddef.h
  stable/10/sys/sys/_types.h
Directory Properties:
  stable/10/   (props changed)

Changes in other areas also in this revision:
Modified:
  stable/11/include/stddef.h
  stable/11/sys/sys/_types.h
Directory Properties:
  stable/11/   (props changed)

Modified: stable/10/include/stddef.h
==============================================================================
--- stable/10/include/stddef.h	Mon Nov 28 17:55:32 2016	(r309257)
+++ stable/10/include/stddef.h	Mon Nov 28 18:36:37 2016	(r309258)
@@ -59,6 +59,14 @@ typedef	___wchar_t	wchar_t;
 #endif
 #endif
 
+#if __STDC_VERSION__ >= 201112L || __cplusplus >= 201103L
+#ifndef __CLANG_MAX_ALIGN_T_DEFINED
+typedef	__max_align_t	max_align_t;
+#define __CLANG_MAX_ALIGN_T_DEFINED
+#define __GCC_MAX_ALIGN_T
+#endif
+#endif
+
 #define	offsetof(type, member)	__offsetof(type, member)
 
 #endif /* _STDDEF_H_ */

Modified: stable/10/sys/sys/_types.h
==============================================================================
--- stable/10/sys/sys/_types.h	Mon Nov 28 17:55:32 2016	(r309257)
+++ stable/10/sys/sys/_types.h	Mon Nov 28 18:36:37 2016	(r309258)
@@ -99,6 +99,11 @@ typedef	__uint_least32_t __char32_t;
 #define	_CHAR32_T_DECLARED
 #endif
 
+typedef struct {
+	long long __max_align1 __aligned(_Alignof(long long));
+	long double __max_align2 __aligned(_Alignof(long double));
+} __max_align_t;
+
 typedef	__uint32_t	__dev_t;	/* device number */
 
 typedef	__uint32_t	__fixpt_t;	/* fixed point number */