1// The -*- C++ -*- dynamic memory management header. 
2 
3// Copyright (C) 1994-2021 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#pragma GCC visibility push(default) 
44 
45extern "C++" { 
46 
47namespace std  
48{ 
49 /** 
50 * @brief Exception possibly thrown by @c new. 
51 * @ingroup exceptions 
52 * 
53 * @c bad_alloc (or classes derived from it) is used to report allocation 
54 * errors from the throwing forms of @c new. */ 
55 class bad_alloc : public exception 
56 { 
57 public: 
58 bad_alloc() throw() { } 
59 
60#if __cplusplus >= 201103L 
61 bad_alloc(const bad_alloc&) = default; 
62 bad_alloc& operator=(const bad_alloc&) = default; 
63#endif 
64 
65 // This declaration is not useless: 
66 // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118 
67 virtual ~bad_alloc() throw(); 
68 
69 // See comment in eh_exception.cc. 
70 virtual const char* what() const throw(); 
71 }; 
72 
73#if __cplusplus >= 201103L 
74 class bad_array_new_length : public bad_alloc 
75 { 
76 public: 
77 bad_array_new_length() throw() { } 
78 
79 // This declaration is not useless: 
80 // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118 
81 virtual ~bad_array_new_length() throw(); 
82 
83 // See comment in eh_exception.cc. 
84 virtual const char* what() const throw(); 
85 }; 
86#endif 
87 
88#if __cpp_aligned_new 
89 enum class align_val_t: size_t {}; 
90#endif 
91 
92 struct nothrow_t 
93 { 
94#if __cplusplus >= 201103L 
95 explicit nothrow_t() = default; 
96#endif 
97 }; 
98 
99 extern const nothrow_t nothrow; 
100 
101 /** If you write your own error handler to be called by @c new, it must 
102 * be of this type. */ 
103 typedef void (*new_handler)(); 
104 
105 /// Takes a replacement handler as the argument, returns the 
106 /// previous handler. 
107 new_handler set_new_handler(new_handler) throw(); 
108 
109#if __cplusplus >= 201103L 
110 /// Return the current new handler. 
111 new_handler get_new_handler() noexcept; 
112#endif 
113} // namespace std 
114 
115//@{ 
116/** These are replaceable signatures: 
117 * - normal single new and delete (no arguments, throw @c bad_alloc on error) 
118 * - normal array new and delete (same) 
119 * - @c nothrow single new and delete (take a @c nothrow argument, return 
120 * @c NULL on error) 
121 * - @c nothrow array new and delete (same) 
122 * 
123 * Placement new and delete signatures (take a memory address argument, 
124 * does nothing) may not be replaced by a user's program. 
125*/ 
126_GLIBCXX_NODISCARD void* operator new(std::size_t) _GLIBCXX_THROW (std::bad_alloc) 
127 __attribute__((__externally_visible__)); 
128_GLIBCXX_NODISCARD void* operator new[](std::size_t) _GLIBCXX_THROW (std::bad_alloc) 
129 __attribute__((__externally_visible__)); 
130void operator delete(void*) _GLIBCXX_USE_NOEXCEPT 
131 __attribute__((__externally_visible__)); 
132void operator delete[](void*) _GLIBCXX_USE_NOEXCEPT 
133 __attribute__((__externally_visible__)); 
134#if __cpp_sized_deallocation 
135void operator delete(void*, std::size_t) _GLIBCXX_USE_NOEXCEPT 
136 __attribute__((__externally_visible__)); 
137void operator delete[](void*, std::size_t) _GLIBCXX_USE_NOEXCEPT 
138 __attribute__((__externally_visible__)); 
139#endif 
140_GLIBCXX_NODISCARD void* operator new(std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT 
141 __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__)); 
142_GLIBCXX_NODISCARD void* operator new[](std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT 
143 __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__)); 
144void operator delete(void*, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT 
145 __attribute__((__externally_visible__)); 
146void operator delete[](void*, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT 
147 __attribute__((__externally_visible__)); 
148#if __cpp_aligned_new 
149_GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t) 
150 __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__)); 
151_GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t, const std::nothrow_t&) 
152 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__)); 
153void operator delete(void*, std::align_val_t) 
154 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 
155void operator delete(void*, std::align_val_t, const std::nothrow_t&) 
156 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 
157_GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t) 
158 __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__)); 
159_GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t, const std::nothrow_t&) 
160 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__)); 
161void operator delete[](void*, std::align_val_t) 
162 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 
163void operator delete[](void*, std::align_val_t, const std::nothrow_t&) 
164 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 
165#if __cpp_sized_deallocation 
166void operator delete(void*, std::size_t, std::align_val_t) 
167 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 
168void operator delete[](void*, std::size_t, std::align_val_t) 
169 _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__)); 
170#endif // __cpp_sized_deallocation 
171#endif // __cpp_aligned_new 
172 
173// Default placement versions of operator new. 
174_GLIBCXX_NODISCARD inline void* operator new(std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT 
175{ return __p; } 
176_GLIBCXX_NODISCARD inline void* operator new[](std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT 
177{ return __p; } 
178 
179// Default placement versions of operator delete. 
180inline void operator delete (void*, void*) _GLIBCXX_USE_NOEXCEPT { } 
181inline void operator delete[](void*, void*) _GLIBCXX_USE_NOEXCEPT { } 
182//@} 
183} // extern "C++" 
184 
185#if __cplusplus >= 201703L 
186#ifdef _GLIBCXX_HAVE_BUILTIN_LAUNDER 
187namespace std 
188{ 
189#define __cpp_lib_launder 201606 
190 /// Pointer optimization barrier [ptr.launder] 
191 template<typename _Tp> 
192 [[nodiscard]] constexpr _Tp* 
193 launder(_Tp* __p) noexcept 
194 { return __builtin_launder(__p); } 
195 
196 // The program is ill-formed if T is a function type or 
197 // (possibly cv-qualified) void. 
198 
199 template<typename _Ret, typename... _Args _GLIBCXX_NOEXCEPT_PARM> 
200 void launder(_Ret (*)(_Args...) _GLIBCXX_NOEXCEPT_QUAL) = delete; 
201 template<typename _Ret, typename... _Args _GLIBCXX_NOEXCEPT_PARM> 
202 void launder(_Ret (*)(_Args......) _GLIBCXX_NOEXCEPT_QUAL) = delete; 
203 
204 void launder(void*) = delete; 
205 void launder(const void*) = delete; 
206 void launder(volatile void*) = delete; 
207 void launder(const volatile void*) = delete; 
208} 
209#endif // _GLIBCXX_HAVE_BUILTIN_LAUNDER 
210#endif // C++17 
211 
212#if __cplusplus > 201703L 
213namespace std 
214{ 
215 /// Tag type used to declare a class-specific operator delete that can 
216 /// invoke the destructor before deallocating the memory. 
217 struct destroying_delete_t 
218 { 
219 explicit destroying_delete_t() = default; 
220 }; 
221 /// Tag variable of type destroying_delete_t. 
222 inline constexpr destroying_delete_t destroying_delete{}; 
223} 
224// Only define the feature test macro if the compiler supports the feature: 
225#if __cpp_impl_destroying_delete 
226# define __cpp_lib_destroying_delete 201806L 
227#endif 
228#endif // C++20 
229 
230#pragma GCC visibility pop 
231 
232#endif 
233