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