libstdc++

exception
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1 // Exception Handling support header for -*- C++ -*-
2
3 // Copyright (C) 1995-2013 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/atomic_lockfree_defines.h>
39
40 extern "C++" {
41
42 namespace std
43 {
44 /**
45 * @defgroup exceptions Exceptions
46 * @ingroup diagnostics
47 *
48 * Classes and functions for reporting errors via exception classes.
49 * @{
50 */
51
52 /**
53 * @brief Base class for all library exceptions.
54 *
55 * This is the base class for all exceptions thrown by the standard
56 * library, and by certain language expressions. You are free to derive
57 * your own %exception classes, or use a different hierarchy, or to
58 * throw non-class data (e.g., fundamental types).
59 */
60 class exception
61 {
62 public:
63 exception() _GLIBCXX_USE_NOEXCEPT { }
64 virtual ~exception() _GLIBCXX_USE_NOEXCEPT;
65
66 /** Returns a C-style character string describing the general cause
67 * of the current error. */
68 virtual const char* what() const _GLIBCXX_USE_NOEXCEPT;
69 };
70
71 /** If an %exception is thrown which is not listed in a function's
72 * %exception specification, one of these may be thrown. */
73 class bad_exception : public exception
74 {
75 public:
76 bad_exception() _GLIBCXX_USE_NOEXCEPT { }
77
78 // This declaration is not useless:
79 // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118
80 virtual ~bad_exception() _GLIBCXX_USE_NOEXCEPT;
81
82 // See comment in eh_exception.cc.
83 virtual const char* what() const _GLIBCXX_USE_NOEXCEPT;
84 };
85
86 /// If you write a replacement %terminate handler, it must be of this type.
87 typedef void (*terminate_handler) ();
88
89 /// If you write a replacement %unexpected handler, it must be of this type.
90 typedef void (*unexpected_handler) ();
91
92 /// Takes a new handler function as an argument, returns the old function.
93 terminate_handler set_terminate(terminate_handler) _GLIBCXX_USE_NOEXCEPT;
94
95 /** The runtime will call this function if %exception handling must be
96 * abandoned for any reason. It can also be called by the user. */
97 void terminate() _GLIBCXX_USE_NOEXCEPT __attribute__ ((__noreturn__));
98
99 /// Takes a new handler function as an argument, returns the old function.
100 unexpected_handler set_unexpected(unexpected_handler) _GLIBCXX_USE_NOEXCEPT;
101
102 /** The runtime will call this function if an %exception is thrown which
103 * violates the function's %exception specification. */
104 void unexpected() __attribute__ ((__noreturn__));
105
106 /** [18.6.4]/1: 'Returns true after completing evaluation of a
107 * throw-expression until either completing initialization of the
108 * exception-declaration in the matching handler or entering @c unexpected()
109 * due to the throw; or after entering @c terminate() for any reason
110 * other than an explicit call to @c terminate(). [Note: This includes
111 * stack unwinding [15.2]. end note]'
112 *
113 * 2: 'When @c uncaught_exception() is true, throwing an
114 * %exception can result in a call of @c terminate()
115 * (15.5.1).'
116 */
117 bool uncaught_exception() _GLIBCXX_USE_NOEXCEPT __attribute__ ((__pure__));
118
119 // @} group exceptions
120 } // namespace std
121
122 namespace __gnu_cxx
123 {
124 _GLIBCXX_BEGIN_NAMESPACE_VERSION
125
126 /**
127 * @brief A replacement for the standard terminate_handler which
128 * prints more information about the terminating exception (if any)
129 * on stderr.
130 *
131 * @ingroup exceptions
132 *
133 * Call
134 * @code
135 * std::set_terminate(__gnu_cxx::__verbose_terminate_handler)
136 * @endcode
137 * to use. For more info, see
138 * http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt02ch06s02.html
139 *
140 * In 3.4 and later, this is on by default.
141 */
142 void __verbose_terminate_handler();
143
144 _GLIBCXX_END_NAMESPACE_VERSION
145 } // namespace
146
147 } // extern "C++"
148
149 #pragma GCC visibility pop
150
151 #if (__cplusplus >= 201103L) && (ATOMIC_INT_LOCK_FREE > 1)
152 #include <bits/exception_ptr.h>
153 #include <bits/nested_exception.h>
154 #endif
155
156 #endif