libstdc++
stl_construct.h
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1 // nonstandard construct and destroy functions -*- C++ -*-
2 
3 // Copyright (C) 2001-2015 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  /**
88  * Destroy the object pointed to by a pointer type.
89  */
90  template<typename _Tp>
91  inline void
92  _Destroy(_Tp* __pointer)
93  { __pointer->~_Tp(); }
94 
95  template<bool>
96  struct _Destroy_aux
97  {
98  template<typename _ForwardIterator>
99  static void
100  __destroy(_ForwardIterator __first, _ForwardIterator __last)
101  {
102  for (; __first != __last; ++__first)
103  std::_Destroy(std::__addressof(*__first));
104  }
105  };
106 
107  template<>
108  struct _Destroy_aux<true>
109  {
110  template<typename _ForwardIterator>
111  static void
112  __destroy(_ForwardIterator, _ForwardIterator) { }
113  };
114 
115  /**
116  * Destroy a range of objects. If the value_type of the object has
117  * a trivial destructor, the compiler should optimize all of this
118  * away, otherwise the objects' destructors must be invoked.
119  */
120  template<typename _ForwardIterator>
121  inline void
122  _Destroy(_ForwardIterator __first, _ForwardIterator __last)
123  {
124  typedef typename iterator_traits<_ForwardIterator>::value_type
125  _Value_type;
126  std::_Destroy_aux<__has_trivial_destructor(_Value_type)>::
127  __destroy(__first, __last);
128  }
129 
130  /**
131  * Destroy a range of objects using the supplied allocator. For
132  * nondefault allocators we do not optimize away invocation of
133  * destroy() even if _Tp has a trivial destructor.
134  */
135 
136  template<typename _ForwardIterator, typename _Allocator>
137  void
138  _Destroy(_ForwardIterator __first, _ForwardIterator __last,
139  _Allocator& __alloc)
140  {
141  typedef __gnu_cxx::__alloc_traits<_Allocator> __traits;
142  for (; __first != __last; ++__first)
143  __traits::destroy(__alloc, std::__addressof(*__first));
144  }
145 
146  template<typename _ForwardIterator, typename _Tp>
147  inline void
148  _Destroy(_ForwardIterator __first, _ForwardIterator __last,
150  {
151  _Destroy(__first, __last);
152  }
153 
154 _GLIBCXX_END_NAMESPACE_VERSION
155 } // namespace std
156 
157 #endif /* _STL_CONSTRUCT_H */
158 
_Tp * __addressof(_Tp &__r) noexcept
Same as C++11 std::addressof.
Definition: move.h:47
void _Construct(_T1 *__p, _Args &&...__args)
Definition: stl_construct.h:74
The standard allocator, as per [20.4].
Definition: allocator.h:92
void _Destroy(_Tp *__pointer)
Definition: stl_construct.h:92
ISO C++ entities toplevel namespace is std.
Uniform interface to C++98 and C++0x allocators.