clang 19.0.0git
stddef.h
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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>)
24#undef __need_ptrdiff_t
25#undef __need_size_t
26#undef __need_rsize_t
27#undef __need_wchar_t
28#undef __need_NULL
29#undef __need_nullptr_t
30#undef __need_unreachable
31#undef __need_max_align_t
32#undef __need_offsetof
33#undef __need_wint_t
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)
44#define __need_ptrdiff_t
45#define __need_size_t
46/* ISO9899:2011 7.20 (C11 Annex K): Define rsize_t if __STDC_WANT_LIB_EXT1__ is
47 * enabled. */
48#if defined(__STDC_WANT_LIB_EXT1__) && __STDC_WANT_LIB_EXT1__ >= 1
49#define __need_rsize_t
50#endif
51#define __need_wchar_t
52#define __need_NULL
53#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 202311L) || \
54 defined(__cplusplus)
55#define __need_nullptr_t
56#endif
57#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 202311L
58#define __need_unreachable
59#endif
60#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) || \
61 (defined(__cplusplus) && __cplusplus >= 201103L)
62#define __need_max_align_t
63#endif
64#define __need_offsetof
65/* wint_t is provided by <wchar.h> and not <stddef.h>. It's here
66 * for compatibility, but must be explicitly requested. Therefore
67 * __need_wint_t is intentionally not defined here. */
68#endif
69
70#if defined(__need_ptrdiff_t)
71#include <__stddef_ptrdiff_t.h>
72#undef __need_ptrdiff_t
73#endif /* defined(__need_ptrdiff_t) */
74
75#if defined(__need_size_t)
76#include <__stddef_size_t.h>
77#undef __need_size_t
78#endif /*defined(__need_size_t) */
79
80#if defined(__need_rsize_t)
81#include <__stddef_rsize_t.h>
82#undef __need_rsize_t
83#endif /* defined(__need_rsize_t) */
84
85#if defined(__need_wchar_t)
86#include <__stddef_wchar_t.h>
87#undef __need_wchar_t
88#endif /* defined(__need_wchar_t) */
89
90#if defined(__need_NULL)
91#include <__stddef_null.h>
92#undef __need_NULL
93#endif /* defined(__need_NULL) */
94
95#if defined(__need_nullptr_t)
96#include <__stddef_nullptr_t.h>
97#undef __need_nullptr_t
98#endif /* defined(__need_nullptr_t) */
99
100#if defined(__need_unreachable)
101#include <__stddef_unreachable.h>
102#undef __need_unreachable
103#endif /* defined(__need_unreachable) */
104
105#if defined(__need_max_align_t)
106#include <__stddef_max_align_t.h>
107#undef __need_max_align_t
108#endif /* defined(__need_max_align_t) */
109
110#if defined(__need_offsetof)
111#include <__stddef_offsetof.h>
112#undef __need_offsetof
113#endif /* defined(__need_offsetof) */
114
115/* Some C libraries expect to see a wint_t here. Others (notably MinGW) will use
116__WINT_TYPE__ directly; accommodate both by requiring __need_wint_t */
117#if defined(__need_wint_t)
118#include <__stddef_wint_t.h>
119#undef __need_wint_t
120#endif /* __need_wint_t */
121
122#endif /* __MVS__ */