]> git.ipfire.org Git - thirdparty/gcc.git/blame - libstdc++-v3/include/bits/stl_construct.h
[vxworks] [ppc] match TARGET_VXWORKS64 to TARGET_64BIT
[thirdparty/gcc.git] / libstdc++-v3 / include / bits / stl_construct.h
CommitLineData
42526146
PE
1// nonstandard construct and destroy functions -*- C++ -*-
2
6441eb6d 3// Copyright (C) 2001-2025 Free Software Foundation, Inc.
42526146
PE
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
748086b7 8// Free Software Foundation; either version 3, or (at your option)
42526146
PE
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
748086b7
JJ
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.
42526146 19
748086b7
JJ
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/>.
42526146 24
725dc051
BK
25/*
26 *
27 * Copyright (c) 1994
28 * Hewlett-Packard Company
29 *
30 * Permission to use, copy, modify, distribute and sell this software
31 * and its documentation for any purpose is hereby granted without fee,
32 * provided that the above copyright notice appear in all copies and
33 * that both that copyright notice and this permission notice appear
34 * in supporting documentation. Hewlett-Packard Company makes no
35 * representations about the suitability of this software for any
36 * purpose. It is provided "as is" without express or implied warranty.
37 *
38 *
39 * Copyright (c) 1996,1997
40 * Silicon Graphics Computer Systems, Inc.
41 *
42 * Permission to use, copy, modify, distribute and sell this software
43 * and its documentation for any purpose is hereby granted without fee,
44 * provided that the above copyright notice appear in all copies and
45 * that both that copyright notice and this permission notice appear
46 * in supporting documentation. Silicon Graphics makes no
47 * representations about the suitability of this software for any
48 * purpose. It is provided "as is" without express or implied warranty.
49 */
50
f910786b 51/** @file bits/stl_construct.h
729e3d3f 52 * This is an internal header file, included by other library headers.
f910786b 53 * Do not attempt to use it directly. @headername{memory}
725dc051
BK
54 */
55
3d7c150e
BK
56#ifndef _STL_CONSTRUCT_H
57#define _STL_CONSTRUCT_H 1
725dc051 58
a6863e25 59#include <new>
6401164d 60#include <bits/move.h>
85f24114
JW
61#include <bits/stl_iterator_base_types.h> // for iterator_traits
62#include <bits/stl_iterator_base_funcs.h> // for advance
63
64/* This file provides the C++17 functions std::destroy_at, std::destroy, and
65 * std::destroy_n, and the C++20 function std::construct_at.
66 * It also provides std::_Construct, std::_Destroy,and std::_Destroy_n functions
67 * which are defined in all standard modes and so can be used in C++98-14 code.
162c40a4
JW
68 * The _Destroy functions will dispatch to destroy_at during constant
69 * evaluation, because calls to that function are intercepted by the compiler
70 * to allow use in constant expressions.
85f24114 71 */
725dc051 72
12ffa228
BK
73namespace std _GLIBCXX_VISIBILITY(default)
74{
75_GLIBCXX_BEGIN_NAMESPACE_VERSION
3cbc7af0 76
8539c561 77#if __glibcxx_raw_memory_algorithms // >= C++17
85f24114
JW
78 template <typename _Tp>
79 _GLIBCXX20_CONSTEXPR inline void
80 destroy_at(_Tp* __location)
81 {
82 if constexpr (__cplusplus > 201703L && is_array_v<_Tp>)
83 {
84 for (auto& __x : *__location)
1e807763 85 std::destroy_at(std::addressof(__x));
85f24114
JW
86 }
87 else
88 __location->~_Tp();
89 }
90
8539c561 91#if __cpp_constexpr_dynamic_alloc // >= C++20
85f24114 92 template<typename _Tp, typename... _Args>
993deb3a
JW
93 requires (!is_unbounded_array_v<_Tp>)
94 && requires { ::new((void*)0) _Tp(std::declval<_Args>()...); }
95 constexpr _Tp*
85f24114
JW
96 construct_at(_Tp* __location, _Args&&... __args)
97 noexcept(noexcept(::new((void*)0) _Tp(std::declval<_Args>()...)))
993deb3a 98 {
2eaae1bd 99 void* __loc = __location;
993deb3a
JW
100 // _GLIBCXX_RESOLVE_LIB_DEFECTS
101 // 3436. std::construct_at should support arrays
102 if constexpr (is_array_v<_Tp>)
103 {
104 static_assert(sizeof...(_Args) == 0, "std::construct_at for array "
105 "types must not use any arguments to initialize the "
106 "array");
107 return ::new(__loc) _Tp[1]();
108 }
109 else
110 return ::new(__loc) _Tp(std::forward<_Args>(__args)...);
111 }
85f24114
JW
112#endif // C++20
113#endif// C++17
114
494fff4c 115 /**
b0037845
PE
116 * Constructs an object in existing memory by invoking an allocated
117 * object's constructor with an initializer.
494fff4c 118 */
734f5023 119#if __cplusplus >= 201103L
85f24114 120 template<typename _Tp, typename... _Args>
476f305b 121 _GLIBCXX20_CONSTEXPR
162c40a4 122 inline void
85f24114 123 _Construct(_Tp* __p, _Args&&... __args)
476f305b 124 {
8539c561 125#if __cpp_constexpr_dynamic_alloc // >= C++20
1e807763 126 if (std::is_constant_evaluated())
476f305b
JW
127 {
128 // Allow std::_Construct to be used in constant expressions.
129 std::construct_at(__p, std::forward<_Args>(__args)...);
130 return;
131 }
132#endif
2eaae1bd 133 ::new(static_cast<void*>(__p)) _Tp(std::forward<_Args>(__args)...);
476f305b 134 }
55dd8445 135#else
fe27aa8b 136 template<typename _T1, typename _T2>
162c40a4 137 inline void
494fff4c 138 _Construct(_T1* __p, const _T2& __value)
9dbaa948
PC
139 {
140 // _GLIBCXX_RESOLVE_LIB_DEFECTS
141 // 402. wrong new expression in [some_]allocator::construct
162c40a4 142 ::new(static_cast<void*>(__p)) _T1(__value);
9dbaa948 143 }
fe27aa8b 144#endif
ed6814f7 145
377f30c0 146 template<typename _T1>
3052b336 147 _GLIBCXX26_CONSTEXPR
377f30c0
VV
148 inline void
149 _Construct_novalue(_T1* __p)
2eaae1bd 150 { ::new(static_cast<void*>(__p)) _T1; }
377f30c0 151
85f24114
JW
152 template<typename _ForwardIterator>
153 _GLIBCXX20_CONSTEXPR void
154 _Destroy(_ForwardIterator __first, _ForwardIterator __last);
155
da73f9de 156 /**
da73f9de 157 * Destroy the object pointed to by a pointer type.
da73f9de 158 */
d78e147a 159 template<typename _Tp>
540218dd 160 _GLIBCXX14_CONSTEXPR inline void
da73f9de 161 _Destroy(_Tp* __pointer)
85f24114 162 {
8539c561 163#if __cpp_constexpr_dynamic_alloc // >= C++20
85f24114
JW
164 std::destroy_at(__pointer);
165#else
166 __pointer->~_Tp();
167#endif
168 }
da73f9de 169
1467409b
JW
170#pragma GCC diagnostic push
171#pragma GCC diagnostic ignored "-Wc++17-extensions" // for if-constexpr
172
173#if __cplusplus < 201103L
cf0e6fff
PC
174 template<bool>
175 struct _Destroy_aux
176 {
177 template<typename _ForwardIterator>
85f24114
JW
178 static _GLIBCXX20_CONSTEXPR void
179 __destroy(_ForwardIterator __first, _ForwardIterator __last)
cf0e6fff
PC
180 {
181 for (; __first != __last; ++__first)
882b3d5c 182 std::_Destroy(std::__addressof(*__first));
cf0e6fff 183 }
01789efa
JW
184
185 template<typename _ForwardIterator, typename _Size>
186 static _GLIBCXX20_CONSTEXPR _ForwardIterator
187 __destroy_n(_ForwardIterator __first, _Size __count)
188 {
189 for (; __count > 0; (void)++__first, --__count)
190 std::_Destroy(std::__addressof(*__first));
191 return __first;
192 }
cf0e6fff
PC
193 };
194
195 template<>
196 struct _Destroy_aux<true>
197 {
198 template<typename _ForwardIterator>
199 static void
200 __destroy(_ForwardIterator, _ForwardIterator) { }
01789efa
JW
201
202 template<typename _ForwardIterator, typename _Size>
203 static _ForwardIterator
204 __destroy_n(_ForwardIterator __first, _Size __count)
205 {
206 std::advance(__first, __count);
207 return __first;
208 }
cf0e6fff 209 };
1467409b 210#endif
cf0e6fff 211
494fff4c
SW
212 /**
213 * Destroy a range of objects. If the value_type of the object has
214 * a trivial destructor, the compiler should optimize all of this
215 * away, otherwise the objects' destructors must be invoked.
494fff4c 216 */
d78e147a 217 template<typename _ForwardIterator>
85f24114 218 _GLIBCXX20_CONSTEXPR inline void
494fff4c
SW
219 _Destroy(_ForwardIterator __first, _ForwardIterator __last)
220 {
221 typedef typename iterator_traits<_ForwardIterator>::value_type
222 _Value_type;
b26f45f0 223#if __cplusplus >= 201103L
01789efa 224 if constexpr (!is_trivially_destructible<_Value_type>::value)
1467409b 225 for (; __first != __last; ++__first)
1e807763 226 std::_Destroy(std::addressof(*__first));
8539c561 227#if __cpp_constexpr_dynamic_alloc // >= C++20
1e807763 228 else if (std::is_constant_evaluated())
1467409b 229 for (; __first != __last; ++__first)
1e807763 230 std::destroy_at(std::addressof(*__first));
b26f45f0 231#endif
1467409b 232#else
cf0e6fff
PC
233 std::_Destroy_aux<__has_trivial_destructor(_Value_type)>::
234 __destroy(__first, __last);
1467409b 235#endif
494fff4c 236 }
1985f1cd 237
377f30c0
VV
238 /**
239 * Destroy a range of objects. If the value_type of the object has
240 * a trivial destructor, the compiler should optimize all of this
241 * away, otherwise the objects' destructors must be invoked.
242 */
243 template<typename _ForwardIterator, typename _Size>
85f24114 244 _GLIBCXX20_CONSTEXPR inline _ForwardIterator
377f30c0
VV
245 _Destroy_n(_ForwardIterator __first, _Size __count)
246 {
247 typedef typename iterator_traits<_ForwardIterator>::value_type
248 _Value_type;
b26f45f0 249#if __cplusplus >= 201103L
01789efa 250 if constexpr (!is_trivially_destructible<_Value_type>::value)
1467409b 251 for (; __count > 0; (void)++__first, --__count)
1e807763 252 std::_Destroy(std::addressof(*__first));
8539c561 253#if __cpp_constexpr_dynamic_alloc // >= C++20
1e807763 254 else if (std::is_constant_evaluated())
1467409b 255 for (; __count > 0; (void)++__first, --__count)
1e807763 256 std::destroy_at(std::addressof(*__first));
b26f45f0 257#endif
1467409b
JW
258 else
259 std::advance(__first, __count);
260 return __first;
261#else
01789efa 262 return std::_Destroy_aux<__has_trivial_destructor(_Value_type)>::
377f30c0 263 __destroy_n(__first, __count);
1467409b 264#endif
377f30c0 265 }
1467409b 266#pragma GCC diagnostic pop
377f30c0 267
8539c561 268#if __glibcxx_raw_memory_algorithms // >= C++17
b26f45f0 269 template <typename _ForwardIterator>
85f24114 270 _GLIBCXX20_CONSTEXPR inline void
b26f45f0
JW
271 destroy(_ForwardIterator __first, _ForwardIterator __last)
272 {
273 std::_Destroy(__first, __last);
274 }
275
276 template <typename _ForwardIterator, typename _Size>
85f24114 277 _GLIBCXX20_CONSTEXPR inline _ForwardIterator
b26f45f0
JW
278 destroy_n(_ForwardIterator __first, _Size __count)
279 {
280 return std::_Destroy_n(__first, __count);
281 }
85f24114 282#endif // C++17
b26f45f0 283
12ffa228 284_GLIBCXX_END_NAMESPACE_VERSION
cd1e6665 285} // namespace std
725dc051 286
3d7c150e 287#endif /* _STL_CONSTRUCT_H */