1 // nonstandard construct and destroy functions -*- C++ -*- 2 3 // Copyright (C) 2001-2018 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 /* 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 51 /** @file bits/stl_construct.h 52 * This is an internal header file, included by other library headers. 53 * Do not attempt to use it directly. @headername{memory} 54 */ 55 56 #ifndef _STL_CONSTRUCT_H 57 #define _STL_CONSTRUCT_H 1 58 59 #include <new> 60 #include <bits/move.h> 61 #include <ext/alloc_traits.h> 62 63 namespace std _GLIBCXX_VISIBILITY(default) 64 { 65 _GLIBCXX_BEGIN_NAMESPACE_VERSION 66 67 /** 68 * Constructs an object in existing memory by invoking an allocated 69 * object's constructor with an initializer. 70 */ 71 #if __cplusplus >= 201103L 72 template<typename _T1, typename... _Args> 73 inline void 74 _Construct(_T1* __p, _Args&&... __args) 75 { ::new(static_cast<void*>(__p)) _T1(std::forward<_Args>(__args)...); } 76 #else 77 template<typename _T1, typename _T2> 78 inline void 79 _Construct(_T1* __p, const _T2& __value) 80 { 81 // _GLIBCXX_RESOLVE_LIB_DEFECTS 82 // 402. wrong new expression in [some_]allocator::construct 83 ::new(static_cast<void*>(__p)) _T1(__value); 84 } 85 #endif 86 87 template<typename _T1> 88 inline void 89 _Construct_novalue(_T1* __p) 90 { ::new(static_cast<void*>(__p)) _T1; } 91 92 /** 93 * Destroy the object pointed to by a pointer type. 94 */ 95 template<typename _Tp> 96 inline void 97 _Destroy(_Tp* __pointer) 98 { __pointer->~_Tp(); } 99 100 template<bool> 101 struct _Destroy_aux 102 { 103 template<typename _ForwardIterator> 104 static void 105 __destroy(_ForwardIterator __first, _ForwardIterator __last) 106 { 107 for (; __first != __last; ++__first) 108 std::_Destroy(std::__addressof(*__first)); 109 } 110 }; 111 112 template<> 113 struct _Destroy_aux<true> 114 { 115 template<typename _ForwardIterator> 116 static void 117 __destroy(_ForwardIterator, _ForwardIterator) { } 118 }; 119 120 /** 121 * Destroy a range of objects. If the value_type of the object has 122 * a trivial destructor, the compiler should optimize all of this 123 * away, otherwise the objects' destructors must be invoked. 124 */ 125 template<typename _ForwardIterator> 126 inline void 127 _Destroy(_ForwardIterator __first, _ForwardIterator __last) 128 { 129 typedef typename iterator_traits<_ForwardIterator>::value_type 130 _Value_type; 131 #if __cplusplus >= 201103L 132 // A deleted destructor is trivial, this ensures we reject such types: 133 static_assert(is_destructible<_Value_type>::value, 134 "value type is destructible"); 135 #endif 136 std::_Destroy_aux<__has_trivial_destructor(_Value_type)>:: 137 __destroy(__first, __last); 138 } 139 140 template<bool> 141 struct _Destroy_n_aux 142 { 143 template<typename _ForwardIterator, typename _Size> 144 static _ForwardIterator 145 __destroy_n(_ForwardIterator __first, _Size __count) 146 { 147 for (; __count > 0; (void)++__first, --__count) 148 std::_Destroy(std::__addressof(*__first)); 149 return __first; 150 } 151 }; 152 153 template<> 154 struct _Destroy_n_aux<true> 155 { 156 template<typename _ForwardIterator, typename _Size> 157 static _ForwardIterator 158 __destroy_n(_ForwardIterator __first, _Size __count) 159 { 160 std::advance(__first, __count); 161 return __first; 162 } 163 }; 164 165 /** 166 * Destroy a range of objects. If the value_type of the object has 167 * a trivial destructor, the compiler should optimize all of this 168 * away, otherwise the objects' destructors must be invoked. 169 */ 170 template<typename _ForwardIterator, typename _Size> 171 inline _ForwardIterator 172 _Destroy_n(_ForwardIterator __first, _Size __count) 173 { 174 typedef typename iterator_traits<_ForwardIterator>::value_type 175 _Value_type; 176 #if __cplusplus >= 201103L 177 // A deleted destructor is trivial, this ensures we reject such types: 178 static_assert(is_destructible<_Value_type>::value, 179 "value type is destructible"); 180 #endif 181 return std::_Destroy_n_aux<__has_trivial_destructor(_Value_type)>:: 182 __destroy_n(__first, __count); 183 } 184 185 /** 186 * Destroy a range of objects using the supplied allocator. For 187 * nondefault allocators we do not optimize away invocation of 188 * destroy() even if _Tp has a trivial destructor. 189 */ 190 191 template<typename _ForwardIterator, typename _Allocator> 192 void 193 _Destroy(_ForwardIterator __first, _ForwardIterator __last, 194 _Allocator& __alloc) 195 { 196 typedef __gnu_cxx::__alloc_traits<_Allocator> __traits; 197 for (; __first != __last; ++__first) 198 __traits::destroy(__alloc, std::__addressof(*__first)); 199 } 200 201 template<typename _ForwardIterator, typename _Tp> 202 inline void 203 _Destroy(_ForwardIterator __first, _ForwardIterator __last, 204 allocator<_Tp>&) 205 { 206 _Destroy(__first, __last); 207 } 208 209 #if __cplusplus > 201402L 210 template <typename _Tp> 211 inline void 212 destroy_at(_Tp* __location) 213 { 214 std::_Destroy(__location); 215 } 216 217 template <typename _ForwardIterator> 218 inline void 219 destroy(_ForwardIterator __first, _ForwardIterator __last) 220 { 221 std::_Destroy(__first, __last); 222 } 223 224 template <typename _ForwardIterator, typename _Size> 225 inline _ForwardIterator 226 destroy_n(_ForwardIterator __first, _Size __count) 227 { 228 return std::_Destroy_n(__first, __count); 229 } 230 #endif 231 232 _GLIBCXX_END_NAMESPACE_VERSION 233 } // namespace std 234 235 #endif /* _STL_CONSTRUCT_H */ 236 237