memory

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// <memory> -*- C++ -*-

// Copyright (C) 2001-2026 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.

// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
// <http://www.gnu.org/licenses/>.

/*
 * Copyright (c) 1997-1999
 * Silicon Graphics Computer Systems, Inc.
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Silicon Graphics makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 *
 */

/** @file include/memory
 *  This is a Standard C++ Library header.
 *  @ingroup memory
 */

#ifndef _GLIBCXX_MEMORY
#define _GLIBCXX_MEMORY 1

#ifdef _GLIBCXX_SYSHDR
#pragma GCC system_header
#endif

/**
 * @defgroup memory Memory
 * @ingroup utilities
 *
 * Components for memory allocation, deallocation, and management.
 */

/**
 * @defgroup pointer_abstractions Pointer Abstractions
 * @ingroup memory
 *
 * Smart pointers, etc.
 */

#include <bits/memoryfwd.h>
#if _GLIBCXX_HOSTED
# include <bits/allocator.h>
# include <bits/stl_tempbuf.h>
#endif
#include <bits/stl_construct.h>
#include <bits/stl_uninitialized.h>
#include <bits/stl_raw_storage_iter.h>

#if __cplusplus >= 201103L
#  include <type_traits>
#  include <bits/align.h>
#  include <bits/uses_allocator.h>
#  include <bits/alloc_traits.h>
#  include <debug/debug.h>
#  include <bits/unique_ptr.h>
# if _GLIBCXX_HOSTED
#  include <bits/shared_ptr.h>
#  include <bits/shared_ptr_atomic.h>
# endif
#endif

#if __cplusplus < 201103L || _GLIBCXX_USE_DEPRECATED
#  include <backward/auto_ptr.h>
#endif

#if __cplusplus > 201703L
#  include <bits/ranges_uninitialized.h>
#  include <bits/uses_allocator_args.h>
#endif

#if __cplusplus > 202002L
#  include <bits/out_ptr.h>
#endif

#if __cplusplus > 202302L
#  include <bits/indirect.h>
#endif

#define __glibcxx_want_addressof_constexpr
#define __glibcxx_want_algorithm_iterator_requirements
#define __glibcxx_want_allocator_traits_is_always_equal
#define __glibcxx_want_assume_aligned
#define __glibcxx_want_atomic_shared_ptr
#define __glibcxx_want_atomic_value_initialization
#define __glibcxx_want_constexpr_dynamic_alloc
#define __glibcxx_want_constexpr_memory
#define __glibcxx_want_enable_shared_from_this
#define __glibcxx_want_indirect
#define __glibcxx_want_is_sufficiently_aligned
#define __glibcxx_want_make_unique
#define __glibcxx_want_out_ptr
#define __glibcxx_want_parallel_algorithm
#define __glibcxx_want_polymorphic
#define __glibcxx_want_ranges
#define __glibcxx_want_raw_memory_algorithms
#define __glibcxx_want_shared_ptr_arrays
#define __glibcxx_want_shared_ptr_weak_type
#define __glibcxx_want_smart_ptr_for_overwrite
#define __glibcxx_want_start_lifetime_as
#define __glibcxx_want_to_address
#define __glibcxx_want_transparent_operators
#define __glibcxx_want_smart_ptr_owner_equality
#define __glibcxx_want_allocate_at_least
#include <bits/version.h>

#if __cplusplus >= 201103L && __cplusplus <= 202002L && _GLIBCXX_HOSTED
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION

/** @defgroup ptr_safety Pointer Safety and Garbage Collection
 *  @ingroup memory
 *
 * Utilities to assist with garbage collection in an implementation
 * that supports <em>strict pointer safety</em>.
 * This implementation only supports <em>relaxed pointer safety</em>
 * and so these functions have no effect.
 *
 * C++11 20.6.4 [util.dynamic.safety], Pointer safety
 *
 * @{
 */

/// Constants representing the different types of pointer safety.
enum class pointer_safety { relaxed, preferred, strict };

/// Inform a garbage collector that an object is still in use.
inline void
declare_reachable(void*) { }

/// Unregister an object previously registered with declare_reachable.
template <typename _Tp>
  inline _Tp*
  undeclare_reachable(_Tp* __p) { return __p; }

/// Inform a garbage collector that a region of memory need not be traced.
inline void
declare_no_pointers(char*, size_t) { }

/// Unregister a range previously registered with declare_no_pointers.
inline void
undeclare_no_pointers(char*, size_t) { }

/// The type of pointer safety supported by the implementation.
inline pointer_safety
get_pointer_safety() noexcept { return pointer_safety::relaxed; }
/// @}

_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
#endif // C++11 to C++20

#ifdef __cpp_lib_parallel_algorithm // C++ >= 17 && HOSTED
// Parallel STL algorithms
# if _PSTL_EXECUTION_POLICIES_DEFINED
// If <execution> has already been included, pull in implementations
#  include <pstl/glue_memory_impl.h>
# else
// Otherwise just pull in forward declarations
#  include <pstl/glue_memory_defs.h>
# endif
#endif // __cpp_lib_parallel_algorithm

#endif /* _GLIBCXX_MEMORY */