xref: /freebsd/contrib/llvm-project/libcxx/include/cstddef (revision 62cfcf62f627e5093fb37026a6d8c98e4d2ef04c)
1// -*- C++ -*-
2//===--------------------------- cstddef ----------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP_CSTDDEF
11#define _LIBCPP_CSTDDEF
12
13/*
14    cstddef synopsis
15
16Macros:
17
18    offsetof(type,member-designator)
19    NULL
20
21namespace std
22{
23
24Types:
25
26    ptrdiff_t
27    size_t
28    max_align_t
29    nullptr_t
30    byte // C++17
31
32}  // std
33
34*/
35
36#include <__config>
37#include <version>
38
39#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
40#pragma GCC system_header
41#endif
42
43// Don't include our own <stddef.h>; we don't want to declare ::nullptr_t.
44#include_next <stddef.h>
45#include <__nullptr>
46
47_LIBCPP_BEGIN_NAMESPACE_STD
48
49using ::ptrdiff_t;
50using ::size_t;
51
52#if defined(__CLANG_MAX_ALIGN_T_DEFINED) || defined(_GCC_MAX_ALIGN_T) || \
53    defined(__DEFINED_max_align_t) || defined(__NetBSD__)
54// Re-use the compiler's <stddef.h> max_align_t where possible.
55using ::max_align_t;
56#else
57typedef long double max_align_t;
58#endif
59
60_LIBCPP_END_NAMESPACE_STD
61
62#if _LIBCPP_STD_VER > 14
63namespace std  // purposefully not versioned
64{
65enum class byte : unsigned char {};
66
67constexpr byte  operator| (byte  __lhs, byte __rhs) noexcept
68{
69    return static_cast<byte>(
70      static_cast<unsigned char>(
71         static_cast<unsigned int>(__lhs) | static_cast<unsigned int>(__rhs)
72    ));
73}
74
75constexpr byte& operator|=(byte& __lhs, byte __rhs) noexcept
76{ return __lhs = __lhs | __rhs; }
77
78constexpr byte  operator& (byte  __lhs, byte __rhs) noexcept
79{
80    return static_cast<byte>(
81      static_cast<unsigned char>(
82         static_cast<unsigned int>(__lhs) & static_cast<unsigned int>(__rhs)
83    ));
84}
85
86constexpr byte& operator&=(byte& __lhs, byte __rhs) noexcept
87{ return __lhs = __lhs & __rhs; }
88
89constexpr byte  operator^ (byte  __lhs, byte __rhs) noexcept
90{
91    return static_cast<byte>(
92      static_cast<unsigned char>(
93         static_cast<unsigned int>(__lhs) ^ static_cast<unsigned int>(__rhs)
94    ));
95}
96
97constexpr byte& operator^=(byte& __lhs, byte __rhs) noexcept
98{ return __lhs = __lhs ^ __rhs; }
99
100constexpr byte  operator~ (byte __b) noexcept
101{
102    return static_cast<byte>(
103      static_cast<unsigned char>(
104        ~static_cast<unsigned int>(__b)
105    ));
106}
107
108}
109
110#include <type_traits>  // rest of byte
111#endif
112
113#endif  // _LIBCPP_CSTDDEF
114