libstdc++
exception
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1 // Exception Handling support header for -*- C++ -*-
2 
3 // Copyright (C) 1995-2024 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 exception
27  * This is a Standard C++ Library header.
28  */
29 
30 #ifndef __EXCEPTION__
31 #define __EXCEPTION__
32 
33 #pragma GCC system_header
34 
35 #include <bits/c++config.h>
36 #include <bits/exception.h>
37 
38 #define __glibcxx_want_uncaught_exceptions
39 #include <bits/version.h>
40 
41 extern "C++" {
42 
43 namespace std _GLIBCXX_VISIBILITY(default)
44 {
45  /** @addtogroup exceptions
46  * @{
47  */
48 
49  /** If an %exception is thrown which is not listed in a function's
50  * %exception specification, one of these may be thrown.
51  *
52  * @ingroup exceptions
53  */
54  class bad_exception : public exception
55  {
56  public:
57  bad_exception() _GLIBCXX_USE_NOEXCEPT { }
58 
59  // This declaration is not useless:
60  // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118
61  virtual ~bad_exception() _GLIBCXX_TXN_SAFE_DYN _GLIBCXX_USE_NOEXCEPT;
62 
63  // See comment in eh_exception.cc.
64  virtual const char*
65  what() const _GLIBCXX_TXN_SAFE_DYN _GLIBCXX_USE_NOEXCEPT;
66  };
67 
68  /// If you write a replacement %terminate handler, it must be of this type.
69  typedef void (*terminate_handler) ();
70 
71  /// Takes a new handler function as an argument, returns the old function.
72  terminate_handler set_terminate(terminate_handler) _GLIBCXX_USE_NOEXCEPT;
73 
74 #if __cplusplus >= 201103L
75  /// Return the current terminate handler.
76  terminate_handler get_terminate() noexcept;
77 #endif
78 
79  /** The runtime will call this function if %exception handling must be
80  * abandoned for any reason. It can also be called by the user. */
81  void terminate() _GLIBCXX_USE_NOEXCEPT __attribute__ ((__noreturn__,__cold__));
82 
83 #if __cplusplus < 201703L || (__cplusplus <= 202002L && _GLIBCXX_USE_DEPRECATED)
84  /// If you write a replacement %unexpected handler, it must be of this type.
85  typedef void (*_GLIBCXX11_DEPRECATED unexpected_handler) ();
86 
87  /** Takes a new handler function as an argument, returns the old function.
88  *
89  * @deprecated Removed from the C++ standard in C++17
90  */
91  _GLIBCXX11_DEPRECATED
92  unexpected_handler set_unexpected(unexpected_handler) _GLIBCXX_USE_NOEXCEPT;
93 
94 #if __cplusplus >= 201103L
95  /** Return the current unexpected handler.
96  *
97  * @since C++11
98  * @deprecated Removed from the C++ standard in C++17
99  */
100  _GLIBCXX11_DEPRECATED
101  unexpected_handler get_unexpected() noexcept;
102 #endif
103 
104  /** The runtime will call this function if an %exception is thrown which
105  * violates the function's %exception specification.
106  *
107  * @deprecated Removed from the C++ standard in C++17
108  */
109  _GLIBCXX11_DEPRECATED
110  void unexpected() __attribute__ ((__noreturn__,__cold__));
111 #endif
112 
113  /** [18.6.4]/1: 'Returns true after completing evaluation of a
114  * throw-expression until either completing initialization of the
115  * exception-declaration in the matching handler or entering `unexpected()`
116  * due to the throw; or after entering `terminate()` for any reason
117  * other than an explicit call to `terminate()`. [Note: This includes
118  * stack unwinding [15.2]. end note]'
119  *
120  * 2: 'When `uncaught_exception()` is true, throwing an
121  * %exception can result in a call of 1terminate()`
122  * (15.5.1).'
123  */
124  _GLIBCXX17_DEPRECATED_SUGGEST("std::uncaught_exceptions()")
125  bool uncaught_exception() _GLIBCXX_USE_NOEXCEPT __attribute__ ((__pure__));
126 
127 #ifdef __cpp_lib_uncaught_exceptions // C++ >= 17 || GNU++ >= 03
128  /** The number of uncaught exceptions.
129  * @since C++17, or any non-strict mode, e.g. `-std=gnu++98`
130  * @see uncaught_exception()
131  */
132  int uncaught_exceptions() _GLIBCXX_USE_NOEXCEPT __attribute__ ((__pure__));
133 #endif
134 
135  /// @} group exceptions
136 } // namespace std
137 
138 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
139 {
140 _GLIBCXX_BEGIN_NAMESPACE_VERSION
141 
142  /**
143  * @brief A replacement for the standard terminate_handler which
144  * prints more information about the terminating exception (if any)
145  * on stderr.
146  *
147  * @ingroup exceptions
148  *
149  * Call
150  * @code
151  * std::set_terminate(__gnu_cxx::__verbose_terminate_handler)
152  * @endcode
153  * to use. For more info, see
154  * http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt02ch06s02.html
155  *
156  * In 3.4 and later, this is on by default.
157  */
158  void __verbose_terminate_handler();
159 
160 _GLIBCXX_END_NAMESPACE_VERSION
161 } // namespace
162 
163 } // extern "C++"
164 
165 #if (__cplusplus >= 201103L)
166 #include <bits/exception_ptr.h>
167 #include <bits/nested_exception.h>
168 #endif
169 
170 #endif