1/*===---- stddef.h - Basic type definitions --------------------------------===
  2 *
  3 * Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
  4 * See https://llvm.org/LICENSE.txt for license information.
  5 * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
  6 *
  7 *===-----------------------------------------------------------------------===
  8 */
  9
 10/*
 11 * This header is designed to be included multiple times. If any of the __need_
 12 * macros are defined, then only that subset of interfaces are provided. This
 13 * can be useful for POSIX headers that need to not expose all of stddef.h, but
 14 * need to use some of its interfaces. Otherwise this header provides all of
 15 * the expected interfaces.
 16 *
 17 * When clang modules are enabled, this header is a textual header to support
 18 * the multiple include behavior. As such, it doesn't directly declare anything
 19 * so that it doesn't add duplicate declarations to all of its includers'
 20 * modules.
 21 */
 22#if defined(__MVS__) && __has_include_next(<stddef.h>)
 23#undef __need_ptrdiff_t
 24#undef __need_size_t
 25#undef __need_rsize_t
 26#undef __need_wchar_t
 27#undef __need_NULL
 28#undef __need_nullptr_t
 29#undef __need_unreachable
 30#undef __need_max_align_t
 31#undef __need_offsetof
 32#undef __need_wint_t
 33#include <__stddef_header_macro.h>
 34#include_next <stddef.h>
 35
 36#else
 37
 38#if !defined(__need_ptrdiff_t) && !defined(__need_size_t) &&                   \
 39    !defined(__need_rsize_t) && !defined(__need_wchar_t) &&                    \
 40    !defined(__need_NULL) && !defined(__need_nullptr_t) &&                     \
 41    !defined(__need_unreachable) && !defined(__need_max_align_t) &&            \
 42    !defined(__need_offsetof) && !defined(__need_wint_t)
 43#define __need_ptrdiff_t
 44#define __need_size_t
 45/* ISO9899:2011 7.20 (C11 Annex K): Define rsize_t if __STDC_WANT_LIB_EXT1__ is
 46 * enabled. */
 47#if defined(__STDC_WANT_LIB_EXT1__) && __STDC_WANT_LIB_EXT1__ >= 1
 48#define __need_rsize_t
 49#endif
 50#define __need_wchar_t
 51#if !defined(__STDDEF_H) || __has_feature(modules)
 52/*
 53 * __stddef_null.h is special when building without modules: if __need_NULL is
 54 * set, then it will unconditionally redefine NULL. To avoid stepping on client
 55 * definitions of NULL, __need_NULL should only be set the first time this
 56 * header is included, that is when __STDDEF_H is not defined. However, when
 57 * building with modules, this header is a textual header and needs to
 58 * unconditionally include __stdef_null.h to support multiple submodules
 59 * exporting _Builtin_stddef.null. Take module SM with submodules A and B, whose
 60 * headers both include stddef.h When SM.A builds, __STDDEF_H will be defined.
 61 * When SM.B builds, the definition from SM.A will leak when building without
 62 * local submodule visibility. stddef.h wouldn't include __stddef_null.h, and
 63 * SM.B wouldn't import _Builtin_stddef.null, and SM.B's `export *` wouldn't
 64 * export NULL as expected. When building with modules, always include
 65 * __stddef_null.h so that everything works as expected.
 66 */
 67#define __need_NULL
 68#endif
 69#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 202311L) ||              \
 70    defined(__cplusplus)
 71#define __need_nullptr_t
 72#endif
 73#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 202311L
 74#define __need_unreachable
 75#endif
 76#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) ||              \
 77    (defined(__cplusplus) && __cplusplus >= 201103L)
 78#define __need_max_align_t
 79#endif
 80#define __need_offsetof
 81/* wint_t is provided by <wchar.h> and not <stddef.h>. It's here
 82 * for compatibility, but must be explicitly requested. Therefore
 83 * __need_wint_t is intentionally not defined here. */
 84#include <__stddef_header_macro.h>
 85#endif
 86
 87#if defined(__need_ptrdiff_t)
 88#include <__stddef_ptrdiff_t.h>
 89#undef __need_ptrdiff_t
 90#endif /* defined(__need_ptrdiff_t) */
 91
 92#if defined(__need_size_t)
 93#include <__stddef_size_t.h>
 94#undef __need_size_t
 95#endif /*defined(__need_size_t) */
 96
 97#if defined(__need_rsize_t)
 98#include <__stddef_rsize_t.h>
 99#undef __need_rsize_t
100#endif /* defined(__need_rsize_t) */
101
102#if defined(__need_wchar_t)
103#include <__stddef_wchar_t.h>
104#undef __need_wchar_t
105#endif /* defined(__need_wchar_t) */
106
107#if defined(__need_NULL)
108#include <__stddef_null.h>
109#undef __need_NULL
110#endif /* defined(__need_NULL) */
111
112#if defined(__need_nullptr_t)
113#include <__stddef_nullptr_t.h>
114#undef __need_nullptr_t
115#endif /* defined(__need_nullptr_t) */
116
117#if defined(__need_unreachable)
118#include <__stddef_unreachable.h>
119#undef __need_unreachable
120#endif /* defined(__need_unreachable) */
121
122#if defined(__need_max_align_t)
123#include <__stddef_max_align_t.h>
124#undef __need_max_align_t
125#endif /* defined(__need_max_align_t) */
126
127#if defined(__need_offsetof)
128#include <__stddef_offsetof.h>
129#undef __need_offsetof
130#endif /* defined(__need_offsetof) */
131
132/* Some C libraries expect to see a wint_t here. Others (notably MinGW) will use
133__WINT_TYPE__ directly; accommodate both by requiring __need_wint_t */
134#if defined(__need_wint_t)
135#include <__stddef_wint_t.h>
136#undef __need_wint_t
137#endif /* __need_wint_t */
138
139#endif /* __MVS__ */