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https://forge.sourceware.org/marek/gcc.git
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233 lines
8.4 KiB
C++
233 lines
8.4 KiB
C++
// The -*- C++ -*- dynamic memory management header.
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// Copyright (C) 1994-2026 Free Software Foundation, Inc.
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// This file is part of GCC.
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//
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// GCC is free software; you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation; either version 3, or (at your option)
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// any later version.
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//
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// GCC is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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//
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// Under Section 7 of GPL version 3, you are granted additional
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// permissions described in the GCC Runtime Library Exception, version
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// 3.1, as published by the Free Software Foundation.
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// You should have received a copy of the GNU General Public License and
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// a copy of the GCC Runtime Library Exception along with this program;
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// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
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// <http://www.gnu.org/licenses/>.
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/** @file new
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* This is a Standard C++ Library header.
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*
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* The header @c new defines several functions to manage dynamic memory and
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* handling memory allocation errors; see
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* https://gcc.gnu.org/onlinedocs/libstdc++/manual/dynamic_memory.html
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* for more.
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*/
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#ifndef _NEW
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#define _NEW
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#ifdef _GLIBCXX_SYSHDR
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#pragma GCC system_header
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#endif
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#include <bits/c++config.h>
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#include <bits/exception.h>
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#define __glibcxx_want_launder
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#define __glibcxx_want_hardware_interference_size
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#define __glibcxx_want_destroying_delete
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#define __glibcxx_want_constexpr_new
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#include <bits/version.h>
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#include <bits/new_except.h> // std::bad_alloc, std::bad_array_new_length
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#pragma GCC diagnostic push
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#pragma GCC diagnostic ignored "-Wc++11-extensions" // scoped enum
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#pragma GCC visibility push(default)
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extern "C++" {
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namespace std
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{
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#if __cpp_aligned_new
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enum class align_val_t: size_t {};
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#endif
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struct nothrow_t
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{
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#if __cplusplus >= 201103L
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explicit nothrow_t() = default;
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#endif
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};
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extern const nothrow_t nothrow;
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/** If you write your own error handler to be called by @c new, it must
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* be of this type. */
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typedef void (*new_handler)();
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/// Takes a replacement handler as the argument, returns the
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/// previous handler.
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new_handler set_new_handler(new_handler) throw();
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#if __cplusplus >= 201103L
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/// Return the current new handler.
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new_handler get_new_handler() noexcept;
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#endif
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} // namespace std
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//@{
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/** These are replaceable signatures:
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* - normal single new and delete (no arguments, throw @c bad_alloc on error)
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* - normal array new and delete (same)
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* - @c nothrow single new and delete (take a @c nothrow argument, return
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* @c NULL on error)
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* - @c nothrow array new and delete (same)
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*
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* Placement new and delete signatures (take a memory address argument,
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* does nothing) may not be replaced by a user's program.
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*/
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_GLIBCXX_NODISCARD void* operator new(std::size_t)
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_GLIBCXX_TXN_SAFE _GLIBCXX_THROW (std::bad_alloc)
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__attribute__((__externally_visible__, __malloc__));
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_GLIBCXX_NODISCARD void* operator new[](std::size_t)
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_GLIBCXX_TXN_SAFE _GLIBCXX_THROW (std::bad_alloc)
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__attribute__((__externally_visible__, __malloc__));
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void operator delete(void*) _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
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__attribute__((__externally_visible__));
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void operator delete[](void*) _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
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__attribute__((__externally_visible__));
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#if __cpp_sized_deallocation
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void operator delete(void*, std::size_t)
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_GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
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__attribute__((__externally_visible__));
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void operator delete[](void*, std::size_t)
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_GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
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__attribute__((__externally_visible__));
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#endif
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_GLIBCXX_NODISCARD void* operator new(std::size_t, const std::nothrow_t&)
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_GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
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__attribute__((__externally_visible__, __alloc_size__ (1), __malloc__));
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_GLIBCXX_NODISCARD void* operator new[](std::size_t, const std::nothrow_t&)
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_GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
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__attribute__((__externally_visible__, __alloc_size__ (1), __malloc__));
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void operator delete(void*, const std::nothrow_t&)
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_GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
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__attribute__((__externally_visible__));
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void operator delete[](void*, const std::nothrow_t&)
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_GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
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__attribute__((__externally_visible__));
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#if __cpp_aligned_new
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_GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t)
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_GLIBCXX_TXN_SAFE
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__attribute__((__externally_visible__, __alloc_size__ (1), __alloc_align__ (2), __malloc__));
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_GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t, const std::nothrow_t&)
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_GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
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__attribute__((__externally_visible__, __alloc_size__ (1), __alloc_align__ (2), __malloc__));
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void operator delete(void*, std::align_val_t) _GLIBCXX_TXN_SAFE
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_GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
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void operator delete(void*, std::align_val_t, const std::nothrow_t&)
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_GLIBCXX_TXN_SAFE
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_GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
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_GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t)
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_GLIBCXX_TXN_SAFE
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__attribute__((__externally_visible__, __alloc_size__ (1), __alloc_align__ (2), __malloc__));
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_GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t, const std::nothrow_t&)
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_GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
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__attribute__((__externally_visible__, __alloc_size__ (1), __alloc_align__ (2), __malloc__));
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void operator delete[](void*, std::align_val_t) _GLIBCXX_TXN_SAFE
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_GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
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void operator delete[](void*, std::align_val_t, const std::nothrow_t&)
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_GLIBCXX_TXN_SAFE
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_GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
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#if __cpp_sized_deallocation
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void operator delete(void*, std::size_t, std::align_val_t) _GLIBCXX_TXN_SAFE
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_GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
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void operator delete[](void*, std::size_t, std::align_val_t) _GLIBCXX_TXN_SAFE
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_GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
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#endif // __cpp_sized_deallocation
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#endif // __cpp_aligned_new
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#if __cpp_lib_constexpr_new >= 202406L
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# define _GLIBCXX_PLACEMENT_CONSTEXPR constexpr
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#else
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# define _GLIBCXX_PLACEMENT_CONSTEXPR inline
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#endif
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// Default placement versions of operator new.
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_GLIBCXX_NODISCARD _GLIBCXX_PLACEMENT_CONSTEXPR
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void* operator new(std::size_t, void* __p)
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_GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
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{ return __p; }
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_GLIBCXX_NODISCARD _GLIBCXX_PLACEMENT_CONSTEXPR
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void* operator new[](std::size_t, void* __p)
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_GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
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{ return __p; }
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// Default placement versions of operator delete.
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_GLIBCXX_PLACEMENT_CONSTEXPR void operator delete (void*, void*)
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_GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
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{ }
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_GLIBCXX_PLACEMENT_CONSTEXPR void operator delete[](void*, void*)
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_GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
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{ }
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#undef _GLIBCXX_PLACEMENT_CONSTEXPR
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//@}
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} // extern "C++"
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namespace std
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{
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#ifdef __cpp_lib_launder // C++ >= 17 && HAVE_BUILTIN_LAUNDER
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/// Pointer optimization barrier [ptr.launder]
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template<typename _Tp>
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[[nodiscard]] constexpr _Tp*
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launder(_Tp* __p) noexcept
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{
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if constexpr (__is_same(const volatile _Tp, const volatile void))
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static_assert(!__is_same(const volatile _Tp, const volatile void),
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"std::launder argument must not be a void pointer");
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#if _GLIBCXX_USE_BUILTIN_TRAIT(__is_function)
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else if constexpr (__is_function(_Tp))
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static_assert(!__is_function(_Tp),
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"std::launder argument must not be a function pointer");
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#endif
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else
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return __builtin_launder(__p);
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return nullptr;
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}
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#endif // __cpp_lib_launder
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#ifdef __cpp_lib_hardware_interference_size // C++ >= 17 && defined(gcc_dest_sz)
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inline constexpr size_t hardware_destructive_interference_size = __GCC_DESTRUCTIVE_SIZE;
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inline constexpr size_t hardware_constructive_interference_size = __GCC_CONSTRUCTIVE_SIZE;
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#endif // __cpp_lib_hardware_interference_size
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// Emitted despite the FTM potentially being undefined.
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#if __cplusplus >= 202002L
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/// Tag type used to declare a class-specific operator delete that can
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/// invoke the destructor before deallocating the memory.
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struct destroying_delete_t
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{
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explicit destroying_delete_t() = default;
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};
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/// Tag variable of type destroying_delete_t.
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inline constexpr destroying_delete_t destroying_delete{};
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#endif // C++20
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}
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#pragma GCC visibility pop
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#pragma GCC diagnostic pop
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#endif
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