c-decl.c (shadow_tag_warned, [...]): Handle _Alignas specifiers.

	* c-decl.c (shadow_tag_warned, grokdeclarator): Handle _Alignas
	specifiers.
	(build_null_declspecs): Initialize align_log and alignas_p fields.
	(declspecs_add_alignas): New.
	* c-parser.c (c_token_starts_declspecs): Handle RID_ALIGNAS.
	(c_parser_declspecs): Handle _Alignas specifiers.
	(c_parser_alignas_specifier): New.
	(c_parser_alignof_expression): Diagnose alignof use for non-C1X.
	Diagnose _Alignof (expression).
	* c-tree.h (struct c_declspecs): Add align_log and alignas_p
	fields.
	(declspecs_add_alignas): Declare.
	* ginclude/stddef.h (max_align_t): Define for C1X and C++11.
	* ginclude/stdalign.h: New.
	* Makefile.in (USER_H): Add stdalign.h.

c-family:
	* c-common.c (c_common_reswords): Add _Alignas and _Alignof.
	(c_sizeof_or_alignof_type): Diagnose alignof applied to a function
	type.
	(check_user_alignment): New.  Split out of
	handle_aligned_attribute.  Disallow integer constants with
	noninteger types.  Conditionally allow zero.
	(handle_aligned_attribute): Use check_user_alignment.
	* c-common.h (RID_ALIGNAS, check_user_alignment): New.

testsuite:
	* g++.dg/cpp0x/alignof3.C, gcc.dg/c1x-align-1.c,
	gcc.dg/c1x-align-2.c, gcc.dg/c1x-align-3.c, gcc.dg/c1x-align-4.c,
	gcc.dg/c90-align-1.c, gcc.dg/c99-align-1.c: New tests.
	* gcc.dg/gnu89-const-expr-1.c, gcc.dg/gnu90-const-expr-1.c,
	gcc.dg/gnu99-const-expr-1.c, gcc.dg/gnu99-static-1.c: Update
	expected diagnostics.

From-SVN: r181048

2 files changed, 54 insertions, 1 deletions

diff --git a/gcc/ginclude/stdalign.h b/gcc/ginclude/stdalign.h
new file mode 100644
index 0000000..fd55ed3
--- /dev/null
+++ b/gcc/ginclude/stdalign.h
@@ -0,0 +1,39 @@
+/* Copyright (C) 2011 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 3, or (at your option)
+any later version.
+
+GCC is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+<http://www.gnu.org/licenses/>.  */
+
+/* ISO C1X: 7.15 Alignment <stdalign.h>.  */
+
+#ifndef _STDALIGN_H
+#define _STDALIGN_H
+
+#ifndef __cplusplus
+
+#define alignas _Alignas
+#define alignof _Alignof
+
+#define __alignas_is_defined 1
+#define __alignof_is_defined 1
+
+#endif
+
+#endif	/* stdalign.h */
diff --git a/gcc/ginclude/stddef.h b/gcc/ginclude/stddef.h
index 565ef7b..1cc3cb4 100644
--- a/gcc/ginclude/stddef.h
+++ b/gcc/ginclude/stddef.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 1989, 1997, 1998, 1999, 2000, 2002, 2004, 2009
+/* Copyright (C) 1989, 1997, 1998, 1999, 2000, 2002, 2004, 2009, 2011
    Free Software Foundation, Inc.
 
 This file is part of GCC.
@@ -412,6 +412,20 @@ typedef __WINT_TYPE__ wint_t;
 /* Offset of member MEMBER in a struct of type TYPE. */
 #define offsetof(TYPE, MEMBER) __builtin_offsetof (TYPE, MEMBER)
 
+#if (defined (__STDC_VERSION__) && __STDC_VERSION__ > 199901L) \
+  || (defined(__cplusplus) && __cplusplus >= 201103L)
+#ifndef _GCC_MAX_ALIGN_T
+#define _GCC_MAX_ALIGN_T
+/* Type whose alignment is supported in every context and is at least
+   as great as that of any standard type not using alignment
+   specifiers.  */
+typedef struct {
+  long long __max_align_ll __attribute__((__aligned__(__alignof__(long long))));
+  long double __max_align_ld __attribute__((__aligned__(__alignof__(long double))));
+} max_align_t;
+#endif
+#endif /* C1X or C++11.  */
+
 #endif /* _STDDEF_H was defined this time */
 
 #endif /* !_STDDEF_H && !_STDDEF_H_ && !_ANSI_STDDEF_H && !__STDDEF_H__