libstdc++
memory
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1// <memory> -*- C++ -*-
2
3// Copyright (C) 2001-2025 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/*
26 * Copyright (c) 1997-1999
27 * Silicon Graphics Computer Systems, Inc.
28 *
29 * Permission to use, copy, modify, distribute and sell this software
30 * and its documentation for any purpose is hereby granted without fee,
31 * provided that the above copyright notice appear in all copies and
32 * that both that copyright notice and this permission notice appear
33 * in supporting documentation. Silicon Graphics makes no
34 * representations about the suitability of this software for any
35 * purpose. It is provided "as is" without express or implied warranty.
36 *
37 */
38
39/** @file include/memory
40 * This is a Standard C++ Library header.
41 * @ingroup memory
42 */
43
44#ifndef _GLIBCXX_MEMORY
45#define _GLIBCXX_MEMORY 1
46
47#ifdef _GLIBCXX_SYSHDR
48#pragma GCC system_header
49#endif
50
51/**
52 * @defgroup memory Memory
53 * @ingroup utilities
54 *
55 * Components for memory allocation, deallocation, and management.
56 */
57
58/**
59 * @defgroup pointer_abstractions Pointer Abstractions
60 * @ingroup memory
61 *
62 * Smart pointers, etc.
63 */
64
65#include <bits/memoryfwd.h>
66#if _GLIBCXX_HOSTED
67# include <bits/allocator.h>
68# include <bits/stl_tempbuf.h>
69#endif
70#include <bits/stl_construct.h>
73
74#if __cplusplus >= 201103L
75# include <type_traits>
76# include <bits/align.h>
77# include <bits/uses_allocator.h>
78# include <bits/alloc_traits.h>
79# include <debug/debug.h>
80# include <bits/unique_ptr.h>
81# if _GLIBCXX_HOSTED
82# include <bits/shared_ptr.h>
84# endif
85#endif
86
87#if __cplusplus < 201103L || _GLIBCXX_USE_DEPRECATED
88# include <backward/auto_ptr.h>
89#endif
90
91#if __cplusplus > 201703L
94#endif
95
96#if __cplusplus > 202002L
97# include <bits/out_ptr.h>
98#endif
99
100#define __glibcxx_want_allocator_traits_is_always_equal
101#define __glibcxx_want_assume_aligned
102#define __glibcxx_want_atomic_shared_ptr
103#define __glibcxx_want_atomic_value_initialization
104#define __glibcxx_want_constexpr_dynamic_alloc
105#define __glibcxx_want_constexpr_memory
106#define __glibcxx_want_enable_shared_from_this
107#define __glibcxx_want_make_unique
108#define __glibcxx_want_out_ptr
109#define __glibcxx_want_parallel_algorithm
110#define __glibcxx_want_ranges
111#define __glibcxx_want_raw_memory_algorithms
112#define __glibcxx_want_shared_ptr_arrays
113#define __glibcxx_want_shared_ptr_weak_type
114#define __glibcxx_want_smart_ptr_for_overwrite
115#define __glibcxx_want_to_address
116#define __glibcxx_want_transparent_operators
117#include <bits/version.h>
118
119#if __cplusplus >= 201103L && __cplusplus <= 202002L && _GLIBCXX_HOSTED
120namespace std _GLIBCXX_VISIBILITY(default)
121{
122_GLIBCXX_BEGIN_NAMESPACE_VERSION
123
124/** @defgroup ptr_safety Pointer Safety and Garbage Collection
125 * @ingroup memory
126 *
127 * Utilities to assist with garbage collection in an implementation
128 * that supports <em>strict pointer safety</em>.
129 * This implementation only supports <em>relaxed pointer safety</em>
130 * and so these functions have no effect.
131 *
132 * C++11 20.6.4 [util.dynamic.safety], Pointer safety
133 *
134 * @{
135 */
136
137/// Constants representing the different types of pointer safety.
138enum class pointer_safety { relaxed, preferred, strict };
139
140/// Inform a garbage collector that an object is still in use.
141inline void
143
144/// Unregister an object previously registered with declare_reachable.
145template <typename _Tp>
146 inline _Tp*
147 undeclare_reachable(_Tp* __p) { return __p; }
148
149/// Inform a garbage collector that a region of memory need not be traced.
150inline void
151declare_no_pointers(char*, size_t) { }
152
153/// Unregister a range previously registered with declare_no_pointers.
154inline void
155undeclare_no_pointers(char*, size_t) { }
156
157/// The type of pointer safety supported by the implementation.
158inline pointer_safety
159get_pointer_safety() noexcept { return pointer_safety::relaxed; }
160/// @}
161
162_GLIBCXX_END_NAMESPACE_VERSION
163} // namespace
164#endif // C++11 to C++20
165
166#ifdef __cpp_lib_parallel_algorithm // C++ >= 17 && HOSTED
167// Parallel STL algorithms
168# if _PSTL_EXECUTION_POLICIES_DEFINED
169// If <execution> has already been included, pull in implementations
170# include <pstl/glue_memory_impl.h>
171# else
172// Otherwise just pull in forward declarations
173# include <pstl/glue_memory_defs.h>
174# endif
175#endif // __cpp_lib_parallel_algorithm
176
177#endif /* _GLIBCXX_MEMORY */
void declare_reachable(void *)
Inform a garbage collector that an object is still in use.
Definition memory:142
pointer_safety get_pointer_safety() noexcept
The type of pointer safety supported by the implementation.
Definition memory:159
void undeclare_no_pointers(char *, size_t)
Unregister a range previously registered with declare_no_pointers.
Definition memory:155
void declare_no_pointers(char *, size_t)
Inform a garbage collector that a region of memory need not be traced.
Definition memory:151
pointer_safety
Constants representing the different types of pointer safety.
Definition memory:138
_Tp * undeclare_reachable(_Tp *__p)
Unregister an object previously registered with declare_reachable.
Definition memory:147
ISO C++ entities toplevel namespace is std.