1 /* A substitute for POSIX 2008 <stddef.h>, for platforms that have issues.
3 Copyright (C) 2009-2017 Free Software Foundation, Inc.
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2, or (at your option)
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, see <https://www.gnu.org/licenses/>. */
18 /* Written by Eric Blake. */
21 * POSIX 2008 <stddef.h> for platforms that have issues.
22 * <http://www.opengroup.org/susv3xbd/stddef.h.html>
26 @PRAGMA_SYSTEM_HEADER@
30 #if defined __need_wchar_t || defined __need_size_t \
31 || defined __need_ptrdiff_t || defined __need_NULL \
32 || defined __need_wint_t
33 /* Special invocation convention inside gcc header files. In
34 particular, gcc provides a version of <stddef.h> that blindly
35 redefines NULL even when __need_wint_t was defined, even though
36 wint_t is not normally provided by <stddef.h>. Hence, we must
37 remember if special invocation has ever been used to obtain wint_t,
38 in which case we need to clean up NULL yet again. */
40 # if !(defined _@GUARD_PREFIX@_STDDEF_H && defined _GL_STDDEF_WINT_T)
42 # define _GL_STDDEF_WINT_T
44 # @INCLUDE_NEXT@ @NEXT_STDDEF_H@
48 /* Normal invocation convention. */
50 # ifndef _@GUARD_PREFIX@_STDDEF_H
52 /* The include_next requires a split double-inclusion guard. */
54 # @INCLUDE_NEXT@ @NEXT_STDDEF_H@
56 /* On NetBSD 5.0, the definition of NULL lacks proper parentheses. */
57 # if (@REPLACE_NULL@ \
58 && (!defined _@GUARD_PREFIX@_STDDEF_H || defined _GL_STDDEF_WINT_T))
61 /* ISO C++ says that the macro NULL must expand to an integer constant
62 expression, hence '((void *) 0)' is not allowed in C++. */
64 /* GNU C++ has a __null macro that behaves like an integer ('int' or
65 'long') but has the same size as a pointer. Use that, to avoid
72 # define NULL ((void *) 0)
76 # ifndef _@GUARD_PREFIX@_STDDEF_H
77 # define _@GUARD_PREFIX@_STDDEF_H
79 /* Some platforms lack wchar_t. */
84 /* Some platforms lack max_align_t. The check for _GCC_MAX_ALIGN_T is
85 a hack in case the configure-time test was done with g++ even though
86 we are currently compiling with gcc. */
87 #if ! (@HAVE_MAX_ALIGN_T@ || defined _GCC_MAX_ALIGN_T)
88 # if !GNULIB_defined_max_align_t
89 /* On the x86, the maximum storage alignment of double, long, etc. is 4,
90 but GCC's C11 ABI for x86 says that max_align_t has an alignment of 8,
91 and the C11 standard allows this. Work around this problem by
92 using __alignof__ (which returns 8 for double) rather than _Alignof
93 (which returns 4), and align each union member accordingly. */
95 # define _GL_STDDEF_ALIGNAS(type) \
96 __attribute__ ((__aligned__ (__alignof__ (type))))
98 # define _GL_STDDEF_ALIGNAS(type) /* */
102 char *__p
_GL_STDDEF_ALIGNAS (char *);
103 double __d
_GL_STDDEF_ALIGNAS (double);
104 long double __ld
_GL_STDDEF_ALIGNAS (long double);
105 long int __i
_GL_STDDEF_ALIGNAS (long int);
107 # define max_align_t rpl_max_align_t
108 # define GNULIB_defined_max_align_t 1
112 # endif /* _@GUARD_PREFIX@_STDDEF_H */
113 # endif /* _@GUARD_PREFIX@_STDDEF_H */
114 #endif /* __need_XXX */