libstdc++
exception
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1 // Exception Handling support header for -*- C++ -*-
2 
3 // Copyright (C) 1995-2023 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 extern "C++" {
39 
40 namespace std _GLIBCXX_VISIBILITY(default)
41 {
42  /** @addtogroup exceptions
43  * @{
44  */
45 
46  /** If an %exception is thrown which is not listed in a function's
47  * %exception specification, one of these may be thrown.
48  *
49  * @ingroup exceptions
50  */
51  class bad_exception : public exception
52  {
53  public:
54  bad_exception() _GLIBCXX_USE_NOEXCEPT { }
55 
56  // This declaration is not useless:
57  // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118
58  virtual ~bad_exception() _GLIBCXX_TXN_SAFE_DYN _GLIBCXX_USE_NOEXCEPT;
59 
60  // See comment in eh_exception.cc.
61  virtual const char*
62  what() const _GLIBCXX_TXN_SAFE_DYN _GLIBCXX_USE_NOEXCEPT;
63  };
64 
65  /// If you write a replacement %terminate handler, it must be of this type.
66  typedef void (*terminate_handler) ();
67 
68  /// Takes a new handler function as an argument, returns the old function.
69  terminate_handler set_terminate(terminate_handler) _GLIBCXX_USE_NOEXCEPT;
70 
71 #if __cplusplus >= 201103L
72  /// Return the current terminate handler.
73  terminate_handler get_terminate() noexcept;
74 #endif
75 
76  /** The runtime will call this function if %exception handling must be
77  * abandoned for any reason. It can also be called by the user. */
78  void terminate() _GLIBCXX_USE_NOEXCEPT __attribute__ ((__noreturn__));
79 
80 #if __cplusplus < 201703L || (__cplusplus <= 202002L && _GLIBCXX_USE_DEPRECATED)
81  /// If you write a replacement %unexpected handler, it must be of this type.
82  typedef void (*_GLIBCXX11_DEPRECATED unexpected_handler) ();
83 
84  /** Takes a new handler function as an argument, returns the old function.
85  *
86  * @deprecated Removed from the C++ standard in C++17
87  */
88  _GLIBCXX11_DEPRECATED
89  unexpected_handler set_unexpected(unexpected_handler) _GLIBCXX_USE_NOEXCEPT;
90 
91 #if __cplusplus >= 201103L
92  /** Return the current unexpected handler.
93  *
94  * @since C++11
95  * @deprecated Removed from the C++ standard in C++17
96  */
97  _GLIBCXX11_DEPRECATED
98  unexpected_handler get_unexpected() noexcept;
99 #endif
100 
101  /** The runtime will call this function if an %exception is thrown which
102  * violates the function's %exception specification.
103  *
104  * @deprecated Removed from the C++ standard in C++17
105  */
106  _GLIBCXX11_DEPRECATED
107  void unexpected() __attribute__ ((__noreturn__));
108 #endif
109 
110  /** [18.6.4]/1: 'Returns true after completing evaluation of a
111  * throw-expression until either completing initialization of the
112  * exception-declaration in the matching handler or entering `unexpected()`
113  * due to the throw; or after entering `terminate()` for any reason
114  * other than an explicit call to `terminate()`. [Note: This includes
115  * stack unwinding [15.2]. end note]'
116  *
117  * 2: 'When `uncaught_exception()` is true, throwing an
118  * %exception can result in a call of 1terminate()`
119  * (15.5.1).'
120  */
121  _GLIBCXX17_DEPRECATED_SUGGEST("std::uncaught_exceptions()")
122  bool uncaught_exception() _GLIBCXX_USE_NOEXCEPT __attribute__ ((__pure__));
123 
124 #if __cplusplus >= 201703L || !defined(__STRICT_ANSI__) // c++17 or gnu++98
125 #define __cpp_lib_uncaught_exceptions 201411L
126  /** The number of uncaught exceptions.
127  * @since C++17, or any non-strict mode, e.g. `-std=gnu++98`
128  * @see uncaught_exception()
129  */
130  int uncaught_exceptions() _GLIBCXX_USE_NOEXCEPT __attribute__ ((__pure__));
131 #endif
132 
133  /// @} group exceptions
134 } // namespace std
135 
136 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
137 {
138 _GLIBCXX_BEGIN_NAMESPACE_VERSION
139 
140  /**
141  * @brief A replacement for the standard terminate_handler which
142  * prints more information about the terminating exception (if any)
143  * on stderr.
144  *
145  * @ingroup exceptions
146  *
147  * Call
148  * @code
149  * std::set_terminate(__gnu_cxx::__verbose_terminate_handler)
150  * @endcode
151  * to use. For more info, see
152  * http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt02ch06s02.html
153  *
154  * In 3.4 and later, this is on by default.
155  */
156  void __verbose_terminate_handler();
157 
158 _GLIBCXX_END_NAMESPACE_VERSION
159 } // namespace
160 
161 } // extern "C++"
162 
163 #if (__cplusplus >= 201103L)
164 #include <bits/exception_ptr.h>
165 #include <bits/nested_exception.h>
166 #endif
167 
168 #endif