1 /* A substitute for POSIX 2008 <stddef.h>, for platforms that have issues. 2 3 Copyright (C) 2009-2022 Free Software Foundation, Inc. 4 5 This file is free software: you can redistribute it and/or modify 6 it under the terms of the GNU Lesser General Public License as 7 published by the Free Software Foundation; either version 2.1 of the 8 License, or (at your option) any later version. 9 10 This file 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 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public License 16 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 17 18 /* Written by Eric Blake. */ 19 20 /* 21 * POSIX 2008 <stddef.h> for platforms that have issues. 22 * <https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/stddef.h.html> 23 */ 24 25 #if __GNUC__ >= 3 26 @PRAGMA_SYSTEM_HEADER@ 27 #endif 28 @PRAGMA_COLUMNS@ 29 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. */ 39 40 # if !(defined _@GUARD_PREFIX@_STDDEF_H && defined _GL_STDDEF_WINT_T) 41 # ifdef __need_wint_t 42 # define _GL_STDDEF_WINT_T 43 # endif 44 # @INCLUDE_NEXT@ @NEXT_STDDEF_H@ 45 /* On TinyCC, make sure that the macros that indicate the special invocation 46 convention get undefined. */ 47 # undef __need_wchar_t 48 # undef __need_size_t 49 # undef __need_ptrdiff_t 50 # undef __need_NULL 51 # undef __need_wint_t 52 # endif 53 54 #else 55 /* Normal invocation convention. */ 56 57 # ifndef _@GUARD_PREFIX@_STDDEF_H 58 59 /* On AIX 7.2, with xlc in 64-bit mode, <stddef.h> defines max_align_t to a 60 type with alignment 4, but 'long' has alignment 8. */ 61 # if defined _AIX && defined __LP64__ 62 # if !GNULIB_defined_max_align_t 63 # ifdef _MAX_ALIGN_T 64 /* /usr/include/stddef.h has already defined max_align_t. Override it. */ 65 typedef long rpl_max_align_t; 66 # define max_align_t rpl_max_align_t 67 # else 68 /* Prevent /usr/include/stddef.h from defining max_align_t. */ 69 typedef long max_align_t; 70 # define _MAX_ALIGN_T 71 # endif 72 # define GNULIB_defined_max_align_t 1 73 # endif 74 # endif 75 76 /* The include_next requires a split double-inclusion guard. */ 77 78 # @INCLUDE_NEXT@ @NEXT_STDDEF_H@ 79 80 /* On NetBSD 5.0, the definition of NULL lacks proper parentheses. */ 81 # if (@REPLACE_NULL@ \ 82 && (!defined _@GUARD_PREFIX@_STDDEF_H || defined _GL_STDDEF_WINT_T)) 83 # undef NULL 84 # ifdef __cplusplus 85 /* ISO C++ says that the macro NULL must expand to an integer constant 86 expression, hence '((void *) 0)' is not allowed in C++. */ 87 # if __GNUG__ >= 3 88 /* GNU C++ has a __null macro that behaves like an integer ('int' or 89 'long') but has the same size as a pointer. Use that, to avoid 90 warnings. */ 91 # define NULL __null 92 # else 93 # define NULL 0L 94 # endif 95 # else 96 # define NULL ((void *) 0) 97 # endif 98 # endif 99 100 # ifndef _@GUARD_PREFIX@_STDDEF_H 101 # define _@GUARD_PREFIX@_STDDEF_H 102 103 /* Some platforms lack wchar_t. */ 104 #if !@HAVE_WCHAR_T@ 105 # define wchar_t int 106 #endif 107 108 /* Some platforms lack max_align_t. The check for _GCC_MAX_ALIGN_T is 109 a hack in case the configure-time test was done with g++ even though 110 we are currently compiling with gcc. 111 On MSVC, max_align_t is defined only in C++ mode, after <cstddef> was 112 included. Its definition is good since it has an alignment of 8 (on x86 113 and x86_64). 114 Similarly on OS/2 kLIBC. */ 115 #if (defined _MSC_VER || (defined __KLIBC__ && !defined __LIBCN__)) \ 116 && defined __cplusplus 117 # include <cstddef> 118 #else 119 # if ! (@HAVE_MAX_ALIGN_T@ || (defined _GCC_MAX_ALIGN_T && !defined __clang__)) 120 # if !GNULIB_defined_max_align_t 121 /* On the x86, the maximum storage alignment of double, long, etc. is 4, 122 but GCC's C11 ABI for x86 says that max_align_t has an alignment of 8, 123 and the C11 standard allows this. Work around this problem by 124 using __alignof__ (which returns 8 for double) rather than _Alignof 125 (which returns 4), and align each union member accordingly. */ 126 # if defined __GNUC__ || (__clang_major__ >= 4) 127 # define _GL_STDDEF_ALIGNAS(type) \ 128 __attribute__ ((__aligned__ (__alignof__ (type)))) 129 # else 130 # define _GL_STDDEF_ALIGNAS(type) /* */ 131 # endif 132 typedef union 133 { 134 char *__p _GL_STDDEF_ALIGNAS (char *); 135 double __d _GL_STDDEF_ALIGNAS (double); 136 long double __ld _GL_STDDEF_ALIGNAS (long double); 137 long int __i _GL_STDDEF_ALIGNAS (long int); 138 } rpl_max_align_t; 139 # define max_align_t rpl_max_align_t 140 # define GNULIB_defined_max_align_t 1 141 # endif 142 # endif 143 #endif 144 145 # endif /* _@GUARD_PREFIX@_STDDEF_H */ 146 # endif /* _@GUARD_PREFIX@_STDDEF_H */ 147 #endif /* __need_XXX */ 148
Indexes created Sat Feb 28 05:31:39 UTC 2026