1// -*- C++ -*-
2//===--------------------------- cstddef ----------------------------------===//
3//
4//                     The LLVM Compiler Infrastructure
5//
6// This file is dual licensed under the MIT and the University of Illinois Open
7// Source Licenses. See LICENSE.TXT for details.
8//
9//===----------------------------------------------------------------------===//
10
11#ifndef _LIBCPP_CSTDDEF
12#define _LIBCPP_CSTDDEF
13
14/*
15    cstddef synopsis
16
17Macros:
18
19    offsetof(type,member-designator)
20    NULL
21
22namespace std
23{
24
25Types:
26
27    ptrdiff_t
28    size_t
29    max_align_t
30    nullptr_t
31
32}  // std
33
34*/
35
36#include <__config>
37
38#ifdef __GLIBC__
39#define __need_NULL
40#define __need_ptrdiff_t
41#define __need_size_t
42#endif  // __GLIBC__
43
44#include <stddef.h>
45
46#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
47#pragma GCC system_header
48#endif
49
50_LIBCPP_BEGIN_NAMESPACE_STD
51
52using ::ptrdiff_t;
53using ::size_t;
54
55#if defined(__CLANG_MAX_ALIGN_T_DEFINED) || defined(_GCC_MAX_ALIGN_T)
56// Re-use the compiler's <stddef.h> max_align_t where possible.
57using ::max_align_t;
58#else
59typedef long double max_align_t;
60#endif
61
62#ifdef _LIBCPP_HAS_NO_NULLPTR
63
64struct _LIBCPP_TYPE_VIS_ONLY nullptr_t
65{
66    void* __lx;
67
68    struct __nat {int __for_bool_;};
69
70    _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR nullptr_t() : __lx(0) {}
71    _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR nullptr_t(int __nat::*) : __lx(0) {}
72
73    _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR operator int __nat::*() const {return 0;}
74
75    template <class _Tp>
76        _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR
77        operator _Tp* () const {return 0;}
78
79    template <class _Tp, class _Up>
80        _LIBCPP_ALWAYS_INLINE
81        operator _Tp _Up::* () const {return 0;}
82
83    friend _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR bool operator==(nullptr_t, nullptr_t) {return true;}
84    friend _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR bool operator!=(nullptr_t, nullptr_t) {return false;}
85    friend _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR bool operator<(nullptr_t, nullptr_t) {return false;}
86    friend _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR bool operator<=(nullptr_t, nullptr_t) {return true;}
87    friend _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR bool operator>(nullptr_t, nullptr_t) {return false;}
88    friend _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR bool operator>=(nullptr_t, nullptr_t) {return true;}
89};
90
91inline _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR nullptr_t __get_nullptr_t() {return nullptr_t(0);}
92
93#define nullptr _VSTD::__get_nullptr_t()
94
95#endif  // _LIBCPP_HAS_NO_NULLPTR
96
97_LIBCPP_END_NAMESPACE_STD
98
99#ifndef _LIBCPP_HAS_NO_NULLPTR
100
101namespace std
102{
103    typedef decltype(nullptr) nullptr_t;
104}
105
106#endif  // _LIBCPP_HAS_NO_NULLPTR
107
108#endif  // _LIBCPP_CSTDDEF
109