1 | // The -*- C++ -*- dynamic memory management header. |
2 | |
3 | // Copyright (C) 1994-2019 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 | #if __cplusplus >= 201103L |
60 | bad_alloc(const bad_alloc&) = default; |
61 | bad_alloc& operator=(const bad_alloc&) = default; |
62 | #endif |
63 | |
64 | // This declaration is not useless: |
65 | // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118 |
66 | virtual ~bad_alloc() throw(); |
67 | |
68 | // See comment in eh_exception.cc. |
69 | virtual const char* what() const throw(); |
70 | }; |
71 | |
72 | #if __cplusplus >= 201103L |
73 | class bad_array_new_length : public bad_alloc |
74 | { |
75 | public: |
76 | bad_array_new_length() throw() { } |
77 | |
78 | // This declaration is not useless: |
79 | // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118 |
80 | virtual ~bad_array_new_length() throw(); |
81 | |
82 | // See comment in eh_exception.cc. |
83 | virtual const char* what() const throw(); |
84 | }; |
85 | #endif |
86 | |
87 | #if __cpp_aligned_new |
88 | enum class align_val_t: size_t {}; |
89 | #endif |
90 | |
91 | struct nothrow_t |
92 | { |
93 | #if __cplusplus >= 201103L |
94 | explicit nothrow_t() = default; |
95 | #endif |
96 | }; |
97 | |
98 | extern const nothrow_t nothrow; |
99 | |
100 | /** If you write your own error handler to be called by @c new, it must |
101 | * be of this type. */ |
102 | typedef void (*new_handler)(); |
103 | |
104 | /// Takes a replacement handler as the argument, returns the |
105 | /// previous handler. |
106 | new_handler set_new_handler(new_handler) throw(); |
107 | |
108 | #if __cplusplus >= 201103L |
109 | /// Return the current new handler. |
110 | new_handler get_new_handler() noexcept; |
111 | #endif |
112 | } // namespace std |
113 | |
114 | //@{ |
115 | /** These are replaceable signatures: |
116 | * - normal single new and delete (no arguments, throw @c bad_alloc on error) |
117 | * - normal array new and delete (same) |
118 | * - @c nothrow single new and delete (take a @c nothrow argument, return |
119 | * @c NULL on error) |
120 | * - @c nothrow array new and delete (same) |
121 | * |
122 | * Placement new and delete signatures (take a memory address argument, |
123 | * does nothing) may not be replaced by a user's program. |
124 | */ |
125 | _GLIBCXX_NODISCARD void* operator new(std::size_t) _GLIBCXX_THROW (std::bad_alloc) |
126 | __attribute__((__externally_visible__)); |
127 | _GLIBCXX_NODISCARD void* operator new[](std::size_t) _GLIBCXX_THROW (std::bad_alloc) |
128 | __attribute__((__externally_visible__)); |
129 | void operator delete(void*) _GLIBCXX_USE_NOEXCEPT |
130 | __attribute__((__externally_visible__)); |
131 | void operator delete[](void*) _GLIBCXX_USE_NOEXCEPT |
132 | __attribute__((__externally_visible__)); |
133 | #if __cpp_sized_deallocation |
134 | void operator delete(void*, std::size_t) _GLIBCXX_USE_NOEXCEPT |
135 | __attribute__((__externally_visible__)); |
136 | void operator delete[](void*, std::size_t) _GLIBCXX_USE_NOEXCEPT |
137 | __attribute__((__externally_visible__)); |
138 | #endif |
139 | _GLIBCXX_NODISCARD void* operator new(std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT |
140 | __attribute__((__externally_visible__, __malloc__)); |
141 | _GLIBCXX_NODISCARD void* operator new[](std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT |
142 | __attribute__((__externally_visible__, __malloc__)); |
143 | void operator delete(void*, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT |
144 | __attribute__((__externally_visible__)); |
145 | void operator delete[](void*, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT |
146 | __attribute__((__externally_visible__)); |
147 | #if __cpp_aligned_new |
148 | _GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t) |
149 | __attribute__((__externally_visible__)); |
150 | _GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t, const std::nothrow_t&) |
151 | _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__, __malloc__)); |
152 | void operator delete(void*, std::align_val_t) |
153 | _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); |
154 | void operator delete(void*, std::align_val_t, const std::nothrow_t&) |
155 | _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); |
156 | _GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t) |
157 | __attribute__((__externally_visible__)); |
158 | _GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t, const std::nothrow_t&) |
159 | _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__, __malloc__)); |
160 | void operator delete[](void*, std::align_val_t) |
161 | _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); |
162 | void operator delete[](void*, std::align_val_t, const std::nothrow_t&) |
163 | _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); |
164 | #if __cpp_sized_deallocation |
165 | void operator delete(void*, std::size_t, std::align_val_t) |
166 | _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); |
167 | void operator delete[](void*, std::size_t, std::align_val_t) |
168 | _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); |
169 | #endif // __cpp_sized_deallocation |
170 | #endif // __cpp_aligned_new |
171 | |
172 | // Default placement versions of operator new. |
173 | _GLIBCXX_NODISCARD inline void* operator new(std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT |
174 | { return __p; } |
175 | _GLIBCXX_NODISCARD inline void* operator new[](std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT |
176 | { return __p; } |
177 | |
178 | // Default placement versions of operator delete. |
179 | inline void operator delete (void*, void*) _GLIBCXX_USE_NOEXCEPT { } |
180 | inline void operator delete[](void*, void*) _GLIBCXX_USE_NOEXCEPT { } |
181 | //@} |
182 | } // extern "C++" |
183 | |
184 | #if __cplusplus >= 201703L |
185 | #ifdef _GLIBCXX_HAVE_BUILTIN_LAUNDER |
186 | namespace std |
187 | { |
188 | #define __cpp_lib_launder 201606 |
189 | /// Pointer optimization barrier [ptr.launder] |
190 | template<typename _Tp> |
191 | [[nodiscard]] constexpr _Tp* |
192 | launder(_Tp* __p) noexcept |
193 | { return __builtin_launder(__p); } |
194 | |
195 | // The program is ill-formed if T is a function type or |
196 | // (possibly cv-qualified) void. |
197 | |
198 | template<typename _Ret, typename... _Args _GLIBCXX_NOEXCEPT_PARM> |
199 | void launder(_Ret (*)(_Args...) _GLIBCXX_NOEXCEPT_QUAL) = delete; |
200 | template<typename _Ret, typename... _Args _GLIBCXX_NOEXCEPT_PARM> |
201 | void launder(_Ret (*)(_Args......) _GLIBCXX_NOEXCEPT_QUAL) = delete; |
202 | |
203 | void launder(void*) = delete; |
204 | void launder(const void*) = delete; |
205 | void launder(volatile void*) = delete; |
206 | void launder(const volatile void*) = delete; |
207 | } |
208 | #endif // _GLIBCXX_HAVE_BUILTIN_LAUNDER |
209 | #endif // C++17 |
210 | |
211 | #if __cplusplus > 201703L |
212 | namespace std |
213 | { |
214 | struct destroying_delete_t |
215 | { |
216 | explicit destroying_delete_t() = default; |
217 | }; |
218 | inline constexpr destroying_delete_t destroying_delete{}; |
219 | } |
220 | // Only define the feature test macro if the compiler supports the feature: |
221 | #if __cpp_impl_destroying_delete |
222 | # define __cpp_lib_destroying_delete 201806L |
223 | #endif |
224 | #endif // C++20 |
225 | |
226 | #pragma GCC visibility pop |
227 | |
228 | #endif |
229 | |