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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 508554 : inline void* operator new(std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT
169 508554 : { 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 0 : 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
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