// The -*- C++ -*- dynamic memory management header. // Copyright (C) 1994-2020 Free Software Foundation, Inc. // This file is part of GCC. // // GCC 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. // // GCC 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/>. /** @file new * This is a Standard C++ Library header. * * The header @c new defines several functions to manage dynamic memory and * handling memory allocation errors; see * https://gcc.gnu.org/onlinedocs/libstdc++/manual/dynamic_memory.html * for more. */ #ifndef _NEW #define _NEW #pragma GCC system_header #include <bits/c++config.h> #include <exception> #pragma GCC visibility push(default) extern "C++" { namespace std { /** * @brief Exception possibly thrown by @c new. * @ingroup exceptions * * @c bad_alloc (or classes derived from it) is used to report allocation * errors from the throwing forms of @c new. */ class bad_alloc : public exception { public: bad_alloc() throw() { } #if __cplusplus >= 201103L bad_alloc(const bad_alloc&) = default; bad_alloc& operator=(const bad_alloc&) = default; #endif // This declaration is not useless: // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118 virtual ~bad_alloc() throw(); // See comment in eh_exception.cc. virtual const char* what() const throw(); }; #if __cplusplus >= 201103L class bad_array_new_length : public bad_alloc { public: bad_array_new_length() throw() { } // This declaration is not useless: // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118 virtual ~bad_array_new_length() throw(); // See comment in eh_exception.cc. virtual const char* what() const throw(); }; #endif #if __cpp_aligned_new enum class align_val_t: size_t {}; #endif struct nothrow_t { #if __cplusplus >= 201103L explicit nothrow_t() = default; #endif }; extern const nothrow_t nothrow; /** If you write your own error handler to be called by @c new, it must * be of this type. */ typedef void (*new_handler)(); /// Takes a replacement handler as the argument, returns the /// previous handler. new_handler set_new_handler(new_handler) throw(); #if __cplusplus >= 201103L /// Return the current new handler. new_handler get_new_handler() noexcept; #endif } // namespace std //@{ /** These are replaceable signatures: * - normal single new and delete (no arguments, throw @c bad_alloc on error) * - normal array new and delete (same) * - @c nothrow single new and delete (take a @c nothrow argument, return * @c NULL on error) * - @c nothrow array new and delete (same) * * Placement new and delete signatures (take a memory address argument, * does nothing) may not be replaced by a user's program. */ _GLIBCXX_NODISCARD void* operator new(std::size_t) _GLIBCXX_THROW (std::bad_alloc) __attribute__((__externally_visible__)); _GLIBCXX_NODISCARD void* operator new[](std::size_t) _GLIBCXX_THROW (std::bad_alloc) __attribute__((__externally_visible__)); void operator delete(void*) _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); void operator delete[](void*) _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); #if __cpp_sized_deallocation void operator delete(void*, std::size_t) _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); void operator delete[](void*, std::size_t) _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); #endif _GLIBCXX_NODISCARD void* operator new(std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__, __malloc__)); _GLIBCXX_NODISCARD void* operator new[](std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__, __malloc__)); void operator delete(void*, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); void operator delete[](void*, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); #if __cpp_aligned_new _GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t) __attribute__((__externally_visible__)); _GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__, __malloc__)); void operator delete(void*, std::align_val_t) _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); void operator delete(void*, std::align_val_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); _GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t) __attribute__((__externally_visible__)); _GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__, __malloc__)); void operator delete[](void*, std::align_val_t) _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); void operator delete[](void*, std::align_val_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); #if __cpp_sized_deallocation void operator delete(void*, std::size_t, std::align_val_t) _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); void operator delete[](void*, std::size_t, std::align_val_t) _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); #endif // __cpp_sized_deallocation #endif // __cpp_aligned_new // Default placement versions of operator new. _GLIBCXX_NODISCARD inline void* operator new(std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT { return __p; } _GLIBCXX_NODISCARD inline void* operator new[](std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT { return __p; } // Default placement versions of operator delete. inline void operator delete (void*, void*) _GLIBCXX_USE_NOEXCEPT { } inline void operator delete[](void*, void*) _GLIBCXX_USE_NOEXCEPT { } //@} } // extern "C++" #if __cplusplus >= 201703L #ifdef _GLIBCXX_HAVE_BUILTIN_LAUNDER namespace std { #define __cpp_lib_launder 201606 /// Pointer optimization barrier [ptr.launder] template<typename _Tp> [[nodiscard]] constexpr _Tp* launder(_Tp* __p) noexcept { return __builtin_launder(__p); } // The program is ill-formed if T is a function type or // (possibly cv-qualified) void. template<typename _Ret, typename... _Args _GLIBCXX_NOEXCEPT_PARM> void launder(_Ret (*)(_Args...) _GLIBCXX_NOEXCEPT_QUAL) = delete; template<typename _Ret, typename... _Args _GLIBCXX_NOEXCEPT_PARM> void launder(_Ret (*)(_Args......) _GLIBCXX_NOEXCEPT_QUAL) = delete; void launder(void*) = delete; void launder(const void*) = delete; void launder(volatile void*) = delete; void launder(const volatile void*) = delete; } #endif // _GLIBCXX_HAVE_BUILTIN_LAUNDER #endif // C++17 #if __cplusplus > 201703L namespace std { /// Tag type used to declare a class-specific operator delete that can /// invoke the destructor before deallocating the memory. struct destroying_delete_t { explicit destroying_delete_t() = default; }; /// Tag variable of type destroying_delete_t. inline constexpr destroying_delete_t destroying_delete{}; } // Only define the feature test macro if the compiler supports the feature: #if __cpp_impl_destroying_delete # define __cpp_lib_destroying_delete 201806L #endif #endif // C++20 #pragma GCC visibility pop #endif