1 // The -*- C++ -*- dynamic memory management header. 2 3 // Copyright (C) 1994-2017 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 * http://gcc.gnu.org/onlinedocs/libstdc++/18_support/howto.html#4 for more. 32 */ 33 34 #ifndef _NEW 35 #define _NEW 36 37 #pragma GCC system_header 38 39 #include <bits/c++config.h> 40 #include <exception> 41 42 #pragma GCC visibility push(default) 43 44 extern "C++" { 45 46 namespace std 47 { 48 /** 49 * @brief Exception possibly thrown by @c new. 50 * @ingroup exceptions 51 * 52 * @c bad_alloc (or classes derived from it) is used to report allocation 53 * errors from the throwing forms of @c new. */ 54 class bad_alloc : public exception 55 { 56 public: 57 bad_alloc() throw() { } 58 59 // This declaration is not useless: 60 // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118 61 virtual ~bad_alloc() throw(); 62 63 // See comment in eh_exception.cc. 64 virtual const char* what() const throw(); 65 }; 66 67 #if __cplusplus >= 201103L 68 class bad_array_new_length : public bad_alloc 69 { 70 public: 71 bad_array_new_length() throw() { }; 72 73 // This declaration is not useless: 74 // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118 75 virtual ~bad_array_new_length() throw(); 76 77 // See comment in eh_exception.cc. 78 virtual const char* what() const throw(); 79 }; 80 #endif 81 82 #if __cpp_aligned_new 83 enum class align_val_t: size_t {}; 84 #endif 85 86 struct nothrow_t 87 { 88 #if __cplusplus >= 201103L 89 explicit nothrow_t() = default; 90 #endif 91 }; 92 93 extern const nothrow_t nothrow; 94 95 /** If you write your own error handler to be called by @c new, it must 96 * be of this type. */ 97 typedef void (*new_handler)(); 98 99 /// Takes a replacement handler as the argument, returns the 100 /// previous handler. 101 new_handler set_new_handler(new_handler) throw(); 102 103 #if __cplusplus >= 201103L 104 /// Return the current new handler. 105 new_handler get_new_handler() noexcept; 106 #endif 107 } // namespace std 108 109 //@{ 110 /** These are replaceable signatures: 111 * - normal single new and delete (no arguments, throw @c bad_alloc on error) 112 * - normal array new and delete (same) 113 * - @c nothrow single new and delete (take a @c nothrow argument, return 114 * @c NULL on error) 115 * - @c nothrow array new and delete (same) 116 * 117 * Placement new and delete signatures (take a memory address argument, 118 * does nothing) may not be replaced by a user's program. 119 */ 120 void* operator new(std::size_t) _GLIBCXX_THROW (std::bad_alloc) 121 __attribute__((__externally_visible__)); 122 void* operator new[](std::size_t) _GLIBCXX_THROW (std::bad_alloc) 123 __attribute__((__externally_visible__)); 124 void operator delete(void*) _GLIBCXX_USE_NOEXCEPT 125 __attribute__((__externally_visible__)); 126 void operator delete[](void*) _GLIBCXX_USE_NOEXCEPT 127 __attribute__((__externally_visible__)); 128 #if __cpp_sized_deallocation 129 void operator delete(void*, std::size_t) _GLIBCXX_USE_NOEXCEPT 130 __attribute__((__externally_visible__)); 131 void operator delete[](void*, std::size_t) _GLIBCXX_USE_NOEXCEPT 132 __attribute__((__externally_visible__)); 133 #endif 134 void* operator new(std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT 135 __attribute__((__externally_visible__)); 136 void* operator new[](std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT 137 __attribute__((__externally_visible__)); 138 void operator delete(void*, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT 139 __attribute__((__externally_visible__)); 140 void operator delete[](void*, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT 141 __attribute__((__externally_visible__)); 142 #if __cpp_aligned_new 143 void* operator new(std::size_t, std::align_val_t) 144 __attribute__((__externally_visible__)); 145 void* operator new(std::size_t, std::align_val_t, const std::nothrow_t&) 146 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 147 void operator delete(void*, std::align_val_t) 148 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 149 void operator delete(void*, std::align_val_t, const std::nothrow_t&) 150 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 151 void* operator new[](std::size_t, std::align_val_t) 152 __attribute__((__externally_visible__)); 153 void* operator new[](std::size_t, std::align_val_t, const std::nothrow_t&) 154 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 155 void operator delete[](void*, std::align_val_t) 156 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 157 void operator delete[](void*, std::align_val_t, const std::nothrow_t&) 158 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 159 #if __cpp_sized_deallocation 160 void operator delete(void*, std::size_t, std::align_val_t) 161 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 162 void operator delete[](void*, std::size_t, std::align_val_t) 163 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 164 #endif // __cpp_sized_deallocation 165 #endif // __cpp_aligned_new 166 167 // Default placement versions of operator new. 168 inline void* operator new(std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT 169 { return __p; } 170 inline void* operator new[](std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT 171 { return __p; } 172 173 // Default placement versions of operator delete. 174 inline void operator delete (void*, void*) _GLIBCXX_USE_NOEXCEPT { } 175 inline void operator delete[](void*, void*) _GLIBCXX_USE_NOEXCEPT { } 176 //@} 177 } // extern "C++" 178 179 #if __cplusplus > 201402L 180 #if __GNUC__ >= 7 181 # define _GLIBCXX_HAVE_BUILTIN_LAUNDER 1 182 #elif defined __has_builtin 183 // For non-GNU compilers: 184 # if __has_builtin(__builtin_launder) 185 # define _GLIBCXX_HAVE_BUILTIN_LAUNDER 1 186 # endif 187 #endif 188 189 #ifdef _GLIBCXX_HAVE_BUILTIN_LAUNDER 190 namespace std 191 { 192 #define __cpp_lib_launder 201606 193 /// Pointer optimization barrier [ptr.launder] 194 template<typename _Tp> 195 constexpr _Tp* 196 launder(_Tp* __p) noexcept 197 { return __builtin_launder(__p); } 198 199 // The program is ill-formed if T is a function type or 200 // (possibly cv-qualified) void. 201 202 template<typename _Ret, typename... _Args _GLIBCXX_NOEXCEPT_PARM> 203 void launder(_Ret (*)(_Args...) _GLIBCXX_NOEXCEPT_QUAL) = delete; 204 template<typename _Ret, typename... _Args _GLIBCXX_NOEXCEPT_PARM> 205 void launder(_Ret (*)(_Args......) _GLIBCXX_NOEXCEPT_QUAL) = delete; 206 207 void launder(void*) = delete; 208 void launder(const void*) = delete; 209 void launder(volatile void*) = delete; 210 void launder(const volatile void*) = delete; 211 } 212 #endif // _GLIBCXX_HAVE_BUILTIN_LAUNDER 213 #undef _GLIBCXX_HAVE_BUILTIN_LAUNDER 214 #endif // C++17 215 216 #pragma GCC visibility pop 217 218 #endif 219