libstdc++
exception
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1 // Exception Handling support header for -*- C++ -*-
2 
3 // Copyright (C) 1995-2021 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 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 #pragma GCC visibility push(default)
36 
37 #include <bits/c++config.h>
38 #include <bits/exception.h>
39 
40 extern "C++" {
41 
42 namespace std
43 {
44  /** @addtogroup exceptions
45  * @{
46  */
47 
48  /** If an %exception is thrown which is not listed in a function's
49  * %exception specification, one of these may be thrown. */
50  class bad_exception : public exception
51  {
52  public:
53  bad_exception() _GLIBCXX_USE_NOEXCEPT { }
54 
55  // This declaration is not useless:
56  // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118
57  virtual ~bad_exception() _GLIBCXX_TXN_SAFE_DYN _GLIBCXX_USE_NOEXCEPT;
58 
59  // See comment in eh_exception.cc.
60  virtual const char*
61  what() const _GLIBCXX_TXN_SAFE_DYN _GLIBCXX_USE_NOEXCEPT;
62  };
63 
64  /// If you write a replacement %terminate handler, it must be of this type.
65  typedef void (*terminate_handler) ();
66 
67  /// If you write a replacement %unexpected handler, it must be of this type.
68  typedef void (*unexpected_handler) ();
69 
70  /// Takes a new handler function as an argument, returns the old function.
72 
73 #if __cplusplus >= 201103L
74  /// Return the current terminate handler.
76 #endif
77 
78  /** The runtime will call this function if %exception handling must be
79  * abandoned for any reason. It can also be called by the user. */
80  void terminate() _GLIBCXX_USE_NOEXCEPT __attribute__ ((__noreturn__));
81 
82  /// Takes a new handler function as an argument, returns the old function.
84 
85 #if __cplusplus >= 201103L
86  /// Return the current unexpected handler.
88 #endif
89 
90  /** The runtime will call this function if an %exception is thrown which
91  * violates the function's %exception specification. */
92  void unexpected() __attribute__ ((__noreturn__));
93 
94  /** [18.6.4]/1: 'Returns true after completing evaluation of a
95  * throw-expression until either completing initialization of the
96  * exception-declaration in the matching handler or entering @c unexpected()
97  * due to the throw; or after entering @c terminate() for any reason
98  * other than an explicit call to @c terminate(). [Note: This includes
99  * stack unwinding [15.2]. end note]'
100  *
101  * 2: 'When @c uncaught_exception() is true, throwing an
102  * %exception can result in a call of @c terminate()
103  * (15.5.1).'
104  */
105  _GLIBCXX17_DEPRECATED
106  bool uncaught_exception() _GLIBCXX_USE_NOEXCEPT __attribute__ ((__pure__));
107 
108 #if __cplusplus >= 201703L || !defined(__STRICT_ANSI__) // c++17 or gnu++98
109 #define __cpp_lib_uncaught_exceptions 201411L
110  /// The number of uncaught exceptions.
111  int uncaught_exceptions() _GLIBCXX_USE_NOEXCEPT __attribute__ ((__pure__));
112 #endif
113 
114  /// @} group exceptions
115 } // namespace std
116 
117 namespace __gnu_cxx
118 {
119 _GLIBCXX_BEGIN_NAMESPACE_VERSION
120 
121  /**
122  * @brief A replacement for the standard terminate_handler which
123  * prints more information about the terminating exception (if any)
124  * on stderr.
125  *
126  * @ingroup exceptions
127  *
128  * Call
129  * @code
130  * std::set_terminate(__gnu_cxx::__verbose_terminate_handler)
131  * @endcode
132  * to use. For more info, see
133  * http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt02ch06s02.html
134  *
135  * In 3.4 and later, this is on by default.
136  */
138 
139 _GLIBCXX_END_NAMESPACE_VERSION
140 } // namespace
141 
142 } // extern "C++"
143 
144 #pragma GCC visibility pop
145 
146 #if (__cplusplus >= 201103L)
147 #include <bits/exception_ptr.h>
148 #include <bits/nested_exception.h>
149 #endif
150 
151 #endif
bool uncaught_exception() noexcept
int uncaught_exceptions() noexcept
The number of uncaught exceptions.
unexpected_handler get_unexpected() noexcept
Return the current unexpected handler.
void(* terminate_handler)()
If you write a replacement terminate handler, it must be of this type.
Definition: exception:65
terminate_handler get_terminate() noexcept
Return the current terminate handler.
unexpected_handler set_unexpected(unexpected_handler) noexcept
Takes a new handler function as an argument, returns the old function.
terminate_handler set_terminate(terminate_handler) noexcept
Takes a new handler function as an argument, returns the old function.
void terminate() noexcept
void(* unexpected_handler)()
If you write a replacement unexpected handler, it must be of this type.
Definition: exception:68
void unexpected()
void __verbose_terminate_handler()
A replacement for the standard terminate_handler which prints more information about the terminating ...
ISO C++ entities toplevel namespace is std.
GNU extensions for public use.
virtual const char * what() const noexcept
Base class for all library exceptions.
Definition: exception.h:61