* doc/posix-headers/stddef.texi (stddef.h): Document max_align_t.
* lib/stddef.in.h (_@GUARD_PREFIX@_STDDEF_H) [__need_wint_t]:
Do not undef, as that might cause max_align_t to be defined twice.
Instead, change use to check for _GL_STDDEF_WINT_T too.
(max_align_t) [!HAVE_MAX_ALIGN_T]: New decl.
* m4/stddef_h.m4 (gl_STDDEF_H, gl_STDDEF_H_DEFAULTS):
Check for max_align_t.
* modules/stddef (stddef.h): Substitute HAVE_MAX_ALIGN_T.
* modules/stddef-tests (Depends-on): Add stdalign.
* tests/test-stddef.c: Test max_align_t.
+2014-12-12 Paul Eggert <eggert@cs.ucla.edu>
+
+ stddef: support C11's max_align_t
+ * doc/posix-headers/stddef.texi (stddef.h): Document max_align_t.
+ * lib/stddef.in.h (_@GUARD_PREFIX@_STDDEF_H) [__need_wint_t]:
+ Do not undef, as that might cause max_align_t to be defined twice.
+ Instead, change use to check for _GL_STDDEF_WINT_T too.
+ (max_align_t) [!HAVE_MAX_ALIGN_T]: New decl.
+ * m4/stddef_h.m4 (gl_STDDEF_H, gl_STDDEF_H_DEFAULTS):
+ Check for max_align_t.
+ * modules/stddef (stddef.h): Substitute HAVE_MAX_ALIGN_T.
+ * modules/stddef-tests (Depends-on): Add stdalign.
+ * tests/test-stddef.c: Test max_align_t.
+
2014-12-11 Daiki Ueno <ueno@gnu.org>
unistd: fix iOS check conditional
Portability problems fixed by Gnulib:
@itemize
+@item
+Some platforms fail to provide @code{max_align_t}, which was added in C11.
+
@item
Some old platforms fail to provide @code{wchar_t}.
# if !(defined _@GUARD_PREFIX@_STDDEF_H && defined _GL_STDDEF_WINT_T)
# ifdef __need_wint_t
-# undef _@GUARD_PREFIX@_STDDEF_H
# define _GL_STDDEF_WINT_T
# endif
# @INCLUDE_NEXT@ @NEXT_STDDEF_H@
# @INCLUDE_NEXT@ @NEXT_STDDEF_H@
-# ifndef _@GUARD_PREFIX@_STDDEF_H
-# define _@GUARD_PREFIX@_STDDEF_H
-
/* On NetBSD 5.0, the definition of NULL lacks proper parentheses. */
-#if @REPLACE_NULL@
-# undef NULL
-# ifdef __cplusplus
+# if (@REPLACE_NULL@ \
+ && (!defined _@GUARD_PREFIX@_STDDEF_H || defined _GL_STDDEF_WINT_T))
+# undef NULL
+# ifdef __cplusplus
/* ISO C++ says that the macro NULL must expand to an integer constant
expression, hence '((void *) 0)' is not allowed in C++. */
-# if __GNUG__ >= 3
+# if __GNUG__ >= 3
/* GNU C++ has a __null macro that behaves like an integer ('int' or
'long') but has the same size as a pointer. Use that, to avoid
warnings. */
-# define NULL __null
-# else
-# define NULL 0L
+# define NULL __null
+# else
+# define NULL 0L
+# endif
+# else
+# define NULL ((void *) 0)
+# endif
# endif
-# else
-# define NULL ((void *) 0)
-# endif
-#endif
+
+# ifndef _@GUARD_PREFIX@_STDDEF_H
+# define _@GUARD_PREFIX@_STDDEF_H
/* Some platforms lack wchar_t. */
#if !@HAVE_WCHAR_T@
# define wchar_t int
#endif
+/* Some platforms lack max_align_t. */
+#if !@HAVE_MAX_ALIGN_T@
+typedef union
+{
+ char *__p;
+ double __d;
+ long double __ld;
+ long int __i;
+} max_align_t;
+#endif
+
# endif /* _@GUARD_PREFIX@_STDDEF_H */
# endif /* _@GUARD_PREFIX@_STDDEF_H */
#endif /* __need_XXX */
-dnl A placeholder for POSIX 2008 <stddef.h>, for platforms that have issues.
-# stddef_h.m4 serial 4
+dnl A placeholder for <stddef.h>, for platforms that have issues.
+# stddef_h.m4 serial 5
dnl Copyright (C) 2009-2014 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
AC_REQUIRE([gl_STDDEF_H_DEFAULTS])
AC_REQUIRE([gt_TYPE_WCHAR_T])
STDDEF_H=
+ AC_CHECK_TYPE([max_align_t], [], [HAVE_MAX_ALIGN_T=0; STDDEF_H=stddef.h],
+ [[#include <stddef.h>
+ ]])
if test $gt_cv_c_wchar_t = no; then
HAVE_WCHAR_T=0
STDDEF_H=stddef.h
[
dnl Assume proper GNU behavior unless another module says otherwise.
REPLACE_NULL=0; AC_SUBST([REPLACE_NULL])
+ HAVE_MAX_ALIGN_T=1; AC_SUBST([HAVE_MAX_ALIGN_T])
HAVE_WCHAR_T=1; AC_SUBST([HAVE_WCHAR_T])
])
-e 's|@''PRAGMA_SYSTEM_HEADER''@|@PRAGMA_SYSTEM_HEADER@|g' \
-e 's|@''PRAGMA_COLUMNS''@|@PRAGMA_COLUMNS@|g' \
-e 's|@''NEXT_STDDEF_H''@|$(NEXT_STDDEF_H)|g' \
+ -e 's|@''HAVE_MAX_ALIGN_T''@|$(HAVE_MAX_ALIGN_T)|g' \
-e 's|@''HAVE_WCHAR_T''@|$(HAVE_WCHAR_T)|g' \
-e 's|@''REPLACE_NULL''@|$(REPLACE_NULL)|g' \
< $(srcdir)/stddef.in.h; \
tests/test-stddef.c
Depends-on:
+stdalign
verify
configure.ac:
#include <config.h>
#include <stddef.h>
-
+#include <stdalign.h>
#include "verify.h"
/* Check that appropriate types are defined. */
wchar_t a = 'c';
ptrdiff_t b = 1;
size_t c = 2;
+max_align_t x;
/* Check that NULL can be passed through varargs as a pointer type,
per POSIX 2008. */
verify (offsetof (struct d, e) < -1); /* Must be unsigned. */
verify (offsetof (struct d, f) == 1);
+/* Check max_align_t's alignment. */
+verify (alignof (double) <= alignof (max_align_t));
+verify (alignof (int) <= alignof (max_align_t));
+verify (alignof (long double) <= alignof (max_align_t));
+verify (alignof (long int) <= alignof (max_align_t));
+verify (alignof (ptrdiff_t) <= alignof (max_align_t));
+verify (alignof (size_t) <= alignof (max_align_t));
+verify (alignof (wchar_t) <= alignof (max_align_t));
+verify (alignof (struct d) <= alignof (max_align_t));
+
int
main (void)
{