libstdc++
cstddef
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1 // -*- C++ -*- forwarding header.
2 
3 // Copyright (C) 1997-2025 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15 
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19 
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24 
25 /** @file cstddef
26  * This is a Standard C++ Library file. You should @c \#include this file
27  * in your programs, rather than any of the @a *.h implementation files.
28  *
29  * This is the C++ version of the Standard C Library header @c stddef.h,
30  * and its contents are (mostly) the same as that header, but are all
31  * contained in the namespace @c std (except for names which are defined
32  * as macros in C).
33  */
34 
35 //
36 // ISO C++ 14882: 18.1 Types
37 //
38 
39 #ifndef _GLIBCXX_CSTDDEF
40 #define _GLIBCXX_CSTDDEF 1
41 
42 #ifdef _GLIBCXX_SYSHDR
43 #pragma GCC system_header
44 #endif
45 
46 #undef __need_wchar_t
47 #undef __need_ptrdiff_t
48 #undef __need_size_t
49 #undef __need_NULL
50 #undef __need_wint_t
51 #include <bits/c++config.h>
52 #include <stddef.h>
53 
54 #define __glibcxx_want_byte
55 #include <bits/version.h>
56 
57 #pragma GCC diagnostic push
58 #pragma GCC diagnostic ignored "-Wpedantic" // __int128
59 
60 extern "C++"
61 {
62 #if __cplusplus >= 201103L
63 namespace std
64 {
65  // We handle size_t, ptrdiff_t, and nullptr_t in c++config.h.
66  using ::max_align_t;
67 }
68 #endif // C++11
69 
70 #ifdef __cpp_lib_byte // C++ >= 17
71 namespace std
72 {
73 _GLIBCXX_BEGIN_NAMESPACE_VERSION
74  /// std::byte
75  enum class byte : unsigned char {};
76 
77  template<typename _IntegerType> struct __byte_operand { };
78  template<> struct __byte_operand<bool> { using __type = byte; };
79  template<> struct __byte_operand<char> { using __type = byte; };
80  template<> struct __byte_operand<signed char> { using __type = byte; };
81  template<> struct __byte_operand<unsigned char> { using __type = byte; };
82  template<> struct __byte_operand<wchar_t> { using __type = byte; };
83 #ifdef _GLIBCXX_USE_CHAR8_T
84  template<> struct __byte_operand<char8_t> { using __type = byte; };
85 #endif
86  template<> struct __byte_operand<char16_t> { using __type = byte; };
87  template<> struct __byte_operand<char32_t> { using __type = byte; };
88  template<> struct __byte_operand<short> { using __type = byte; };
89  template<> struct __byte_operand<unsigned short> { using __type = byte; };
90  template<> struct __byte_operand<int> { using __type = byte; };
91  template<> struct __byte_operand<unsigned int> { using __type = byte; };
92  template<> struct __byte_operand<long> { using __type = byte; };
93  template<> struct __byte_operand<unsigned long> { using __type = byte; };
94  template<> struct __byte_operand<long long> { using __type = byte; };
95  template<> struct __byte_operand<unsigned long long> { using __type = byte; };
96 #if defined(__GLIBCXX_TYPE_INT_N_0)
97  template<> struct __byte_operand<__GLIBCXX_TYPE_INT_N_0>
98  { using __type = byte; };
99  template<> struct __byte_operand<unsigned __GLIBCXX_TYPE_INT_N_0>
100  { using __type = byte; };
101 #endif
102 #if defined(__GLIBCXX_TYPE_INT_N_1)
103  template<> struct __byte_operand<__GLIBCXX_TYPE_INT_N_1>
104  { using __type = byte; };
105  template<> struct __byte_operand<unsigned __GLIBCXX_TYPE_INT_N_1>
106  { using __type = byte; };
107 #endif
108 #if defined(__GLIBCXX_TYPE_INT_N_2)
109  template<> struct __byte_operand<__GLIBCXX_TYPE_INT_N_2>
110  { using __type = byte; };
111  template<> struct __byte_operand<unsigned __GLIBCXX_TYPE_INT_N_2>
112  { using __type = byte; };
113 #endif
114  template<typename _IntegerType>
115  struct __byte_operand<const _IntegerType>
116  : __byte_operand<_IntegerType> { };
117  template<typename _IntegerType>
118  struct __byte_operand<volatile _IntegerType>
119  : __byte_operand<_IntegerType> { };
120  template<typename _IntegerType>
121  struct __byte_operand<const volatile _IntegerType>
122  : __byte_operand<_IntegerType> { };
123 
124  template<typename _IntegerType>
125  using __byte_op_t = typename __byte_operand<_IntegerType>::__type;
126 
127  template<typename _IntegerType>
128  [[__gnu__::__always_inline__]]
129  constexpr __byte_op_t<_IntegerType>
130  operator<<(byte __b, _IntegerType __shift) noexcept
131  { return (byte)(unsigned char)((unsigned)__b << __shift); }
132 
133  template<typename _IntegerType>
134  [[__gnu__::__always_inline__]]
135  constexpr __byte_op_t<_IntegerType>
136  operator>>(byte __b, _IntegerType __shift) noexcept
137  { return (byte)(unsigned char)((unsigned)__b >> __shift); }
138 
139  [[__gnu__::__always_inline__]]
140  constexpr byte
141  operator|(byte __l, byte __r) noexcept
142  { return (byte)(unsigned char)((unsigned)__l | (unsigned)__r); }
143 
144  [[__gnu__::__always_inline__]]
145  constexpr byte
146  operator&(byte __l, byte __r) noexcept
147  { return (byte)(unsigned char)((unsigned)__l & (unsigned)__r); }
148 
149  [[__gnu__::__always_inline__]]
150  constexpr byte
151  operator^(byte __l, byte __r) noexcept
152  { return (byte)(unsigned char)((unsigned)__l ^ (unsigned)__r); }
153 
154  [[__gnu__::__always_inline__]]
155  constexpr byte
156  operator~(byte __b) noexcept
157  { return (byte)(unsigned char)~(unsigned)__b; }
158 
159  template<typename _IntegerType>
160  [[__gnu__::__always_inline__]]
161  constexpr __byte_op_t<_IntegerType>&
162  operator<<=(byte& __b, _IntegerType __shift) noexcept
163  { return __b = __b << __shift; }
164 
165  template<typename _IntegerType>
166  [[__gnu__::__always_inline__]]
167  constexpr __byte_op_t<_IntegerType>&
168  operator>>=(byte& __b, _IntegerType __shift) noexcept
169  { return __b = __b >> __shift; }
170 
171  [[__gnu__::__always_inline__]]
172  constexpr byte&
173  operator|=(byte& __l, byte __r) noexcept
174  { return __l = __l | __r; }
175 
176  [[__gnu__::__always_inline__]]
177  constexpr byte&
178  operator&=(byte& __l, byte __r) noexcept
179  { return __l = __l & __r; }
180 
181  [[__gnu__::__always_inline__]]
182  constexpr byte&
183  operator^=(byte& __l, byte __r) noexcept
184  { return __l = __l ^ __r; }
185 
186  template<typename _IntegerType>
187  [[nodiscard,__gnu__::__always_inline__]]
188  constexpr _IntegerType
189  to_integer(__byte_op_t<_IntegerType> __b) noexcept
190  { return _IntegerType(__b); }
191 
192 _GLIBCXX_END_NAMESPACE_VERSION
193 } // namespace std
194 #endif // __cpp_lib_byte
195 } // extern "C++"
196 
197 #pragma GCC diagnostic pop
198 
199 #endif // _GLIBCXX_CSTDDEF