1 // The -*- C++ -*- dynamic memory management header. 2 3 // Copyright (C) 1994-2024 Free Software Foundation, Inc. 4 5 // This file is part of GCC. 6 // 7 // GCC is free software; you can redistribute it and/or modify 8 // it under the terms of the GNU General Public License as published by 9 // the Free Software Foundation; either version 3, or (at your option) 10 // any later version. 11 // 12 // GCC is distributed in the hope that it will be useful, 13 // but WITHOUT ANY WARRANTY; without even the implied warranty of 14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 // GNU General Public License for more details. 16 // 17 // Under Section 7 of GPL version 3, you are granted additional 18 // permissions described in the GCC Runtime Library Exception, version 19 // 3.1, as published by the Free Software Foundation. 20 21 // You should have received a copy of the GNU General Public License and 22 // a copy of the GCC Runtime Library Exception along with this program; 23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 24 // <http://www.gnu.org/licenses/>. 25 26 /** @file new 27 * This is a Standard C++ Library header. 28 * 29 * The header @c new defines several functions to manage dynamic memory and 30 * handling memory allocation errors; see 31 * https://gcc.gnu.org/onlinedocs/libstdc++/manual/dynamic_memory.html 32 * for more. 33 */ 34 35 #ifndef _NEW 36 #define _NEW 37 38 #pragma GCC system_header 39 40 #include <bits/c++config.h> 41 #include <bits/exception.h> 42 43 #define __glibcxx_want_launder 44 #define __glibcxx_want_hardware_interference_size 45 #define __glibcxx_want_destroying_delete 46 #include <bits/version.h> 47 48 #pragma GCC visibility push(default) 49 50 extern "C++" { 51 52 namespace std 53 { 54 /** 55 * @brief Exception possibly thrown by @c new. 56 * @ingroup exceptions 57 * 58 * @c bad_alloc (or classes derived from it) is used to report allocation 59 * errors from the throwing forms of @c new. */ 60 class bad_alloc : public exception 61 { 62 public: 63 bad_alloc() throw() { } 64 65 #if __cplusplus >= 201103L 66 bad_alloc(const bad_alloc&) = default; 67 bad_alloc& operator=(const bad_alloc&) = default; 68 #endif 69 70 // This declaration is not useless: 71 // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118 72 virtual ~bad_alloc() throw(); 73 74 // See comment in eh_exception.cc. 75 virtual const char* what() const throw(); 76 }; 77 78 #if __cplusplus >= 201103L 79 class bad_array_new_length : public bad_alloc 80 { 81 public: 82 bad_array_new_length() throw() { } 83 84 // This declaration is not useless: 85 // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118 86 virtual ~bad_array_new_length() throw(); 87 88 // See comment in eh_exception.cc. 89 virtual const char* what() const throw(); 90 }; 91 #endif 92 93 #if __cpp_aligned_new 94 enum class align_val_t: size_t {}; 95 #endif 96 97 struct nothrow_t 98 { 99 #if __cplusplus >= 201103L 100 explicit nothrow_t() = default; 101 #endif 102 }; 103 104 extern const nothrow_t nothrow; 105 106 /** If you write your own error handler to be called by @c new, it must 107 * be of this type. */ 108 typedef void (*new_handler)(); 109 110 /// Takes a replacement handler as the argument, returns the 111 /// previous handler. 112 new_handler set_new_handler(new_handler) throw(); 113 114 #if __cplusplus >= 201103L 115 /// Return the current new handler. 116 new_handler get_new_handler() noexcept; 117 #endif 118 } // namespace std 119 120 //@{ 121 /** These are replaceable signatures: 122 * - normal single new and delete (no arguments, throw @c bad_alloc on error) 123 * - normal array new and delete (same) 124 * - @c nothrow single new and delete (take a @c nothrow argument, return 125 * @c NULL on error) 126 * - @c nothrow array new and delete (same) 127 * 128 * Placement new and delete signatures (take a memory address argument, 129 * does nothing) may not be replaced by a user's program. 130 */ 131 _GLIBCXX_NODISCARD void* operator new(std::size_t) _GLIBCXX_THROW (std::bad_alloc) 132 __attribute__((__externally_visible__)); 133 _GLIBCXX_NODISCARD void* operator new[](std::size_t) _GLIBCXX_THROW (std::bad_alloc) 134 __attribute__((__externally_visible__)); 135 void operator delete(void*) _GLIBCXX_USE_NOEXCEPT 136 __attribute__((__externally_visible__)); 137 void operator delete[](void*) _GLIBCXX_USE_NOEXCEPT 138 __attribute__((__externally_visible__)); 139 #if __cpp_sized_deallocation 140 void operator delete(void*, std::size_t) _GLIBCXX_USE_NOEXCEPT 141 __attribute__((__externally_visible__)); 142 void operator delete[](void*, std::size_t) _GLIBCXX_USE_NOEXCEPT 143 __attribute__((__externally_visible__)); 144 #endif 145 _GLIBCXX_NODISCARD void* operator new(std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT 146 __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__)); 147 _GLIBCXX_NODISCARD void* operator new[](std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT 148 __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__)); 149 void operator delete(void*, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT 150 __attribute__((__externally_visible__)); 151 void operator delete[](void*, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT 152 __attribute__((__externally_visible__)); 153 #if __cpp_aligned_new 154 _GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t) 155 __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__)); 156 _GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t, const std::nothrow_t&) 157 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__)); 158 void operator delete(void*, std::align_val_t) 159 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 160 void operator delete(void*, std::align_val_t, const std::nothrow_t&) 161 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 162 _GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t) 163 __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__)); 164 _GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t, const std::nothrow_t&) 165 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__)); 166 void operator delete[](void*, std::align_val_t) 167 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 168 void operator delete[](void*, std::align_val_t, const std::nothrow_t&) 169 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 170 #if __cpp_sized_deallocation 171 void operator delete(void*, std::size_t, std::align_val_t) 172 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 173 void operator delete[](void*, std::size_t, std::align_val_t) 174 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 175 #endif // __cpp_sized_deallocation 176 #endif // __cpp_aligned_new 177 178 // Default placement versions of operator new. 179 _GLIBCXX_NODISCARD inline void* operator new(std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT 180 { return __p; } 181 _GLIBCXX_NODISCARD inline void* operator new[](std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT 182 { return __p; } 183 184 // Default placement versions of operator delete. 185 inline void operator delete (void*, void*) _GLIBCXX_USE_NOEXCEPT { } 186 inline void operator delete[](void*, void*) _GLIBCXX_USE_NOEXCEPT { } 187 //@} 188 } // extern "C++" 189 190 #if __cplusplus >= 201703L 191 namespace std 192 { 193 #ifdef __cpp_lib_launder // C++ >= 17 && HAVE_BUILTIN_LAUNDER 194 /// Pointer optimization barrier [ptr.launder] 195 template<typename _Tp> 196 [[nodiscard]] constexpr _Tp* 197 launder(_Tp* __p) noexcept 198 { return __builtin_launder(__p); } 199 200 // The program is ill-formed if T is a function type or 201 // (possibly cv-qualified) void. 202 203 template<typename _Ret, typename... _Args _GLIBCXX_NOEXCEPT_PARM> 204 void launder(_Ret (*)(_Args...) _GLIBCXX_NOEXCEPT_QUAL) = delete; 205 template<typename _Ret, typename... _Args _GLIBCXX_NOEXCEPT_PARM> 206 void launder(_Ret (*)(_Args......) _GLIBCXX_NOEXCEPT_QUAL) = delete; 207 208 void launder(void*) = delete; 209 void launder(const void*) = delete; 210 void launder(volatile void*) = delete; 211 void launder(const volatile void*) = delete; 212 #endif // __cpp_lib_launder 213 214 #ifdef __cpp_lib_hardware_interference_size // C++ >= 17 && defined(gcc_dest_sz) 215 inline constexpr size_t hardware_destructive_interference_size = __GCC_DESTRUCTIVE_SIZE; 216 inline constexpr size_t hardware_constructive_interference_size = __GCC_CONSTRUCTIVE_SIZE; 217 #endif // __cpp_lib_hardware_interference_size 218 } 219 #endif // C++17 220 221 // Emitted despite the FTM potentially being undefined. 222 #if __cplusplus > 201703L 223 namespace std 224 { 225 /// Tag type used to declare a class-specific operator delete that can 226 /// invoke the destructor before deallocating the memory. 227 struct destroying_delete_t 228 { 229 explicit destroying_delete_t() = default; 230 }; 231 /// Tag variable of type destroying_delete_t. 232 inline constexpr destroying_delete_t destroying_delete{}; 233 } 234 #endif // C++20 235 236 #pragma GCC visibility pop 237 238 #endif 239
Indexes created Mon Apr 20 00:23:12 UTC 2026