libstdc++
stdexcept_except.h
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1// Exception classes for <stdexcept> -*- C++ -*-
2
3// Copyright (C) 2001-2026 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/** @file bits/stdexcept_except.h
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{stdexcept} */
28
29#ifndef _STDEXCEPT_EXCEPT_H
30#define _STDEXCEPT_EXCEPT_H 1
31
32#include <exception>
33#include <string>
34
35namespace std _GLIBCXX_VISIBILITY(default)
36{
37_GLIBCXX_BEGIN_NAMESPACE_VERSION
38
39#if _GLIBCXX_USE_DUAL_ABI
40#if _GLIBCXX_USE_CXX11_ABI
41#if __cpp_lib_constexpr_exceptions >= 202502L
42 struct __cow_constexpr_string;
43 namespace __detail
44 {
45 extern "C"
46 {
47 void _ZNSt12__cow_stringC2EPKcm(__cow_constexpr_string*, const char*,
48 unsigned long);
49 void _ZNSt12__cow_stringC2EPKcj(__cow_constexpr_string*, const char*,
50 unsigned int);
51 void _ZNSt12__cow_stringC2EPKcy(__cow_constexpr_string*, const char*,
52 unsigned long long);
53 void _ZNSt12__cow_stringC2EPKc(__cow_constexpr_string*, const char*);
54 void _ZNSt12__cow_stringC2ERKS_(__cow_constexpr_string*,
55 const __cow_constexpr_string&) noexcept;
56 void _ZNSt12__cow_stringC2EOS_(__cow_constexpr_string*,
57 __cow_constexpr_string&&) noexcept;
58 void _ZNSt12__cow_stringD2Ev(__cow_constexpr_string*);
59 __cow_constexpr_string&
60 _ZNSt12__cow_stringaSERKS_(__cow_constexpr_string*,
61 const __cow_constexpr_string&) noexcept;
62 __cow_constexpr_string&
63 _ZNSt12__cow_stringaSEOS_(__cow_constexpr_string*,
64 __cow_constexpr_string&&) noexcept;
65 const char*
66 _ZNKSt12__cow_string5c_strEv(const __cow_constexpr_string*) noexcept;
67 }
68 } // namespace __detail
69
70 // Emulates an old COW string when the new std::string is in use,
71 // but in addition is constexpr and uses the __cow_string out of
72 // line cdtors/methods unless manifestly constant evaluated.
73 struct __cow_constexpr_string
74 {
75 union {
76 const char* _M_p;
77 char _M_bytes[sizeof(const char*)];
78 string* _M_str;
79 };
80
81 [[__gnu__::__always_inline__]] constexpr
82 __cow_constexpr_string(const string& __o)
83 {
84 if consteval {
85 _M_str = new string(__o);
86 } else {
87 __cow_constexpr_string_ctor(__o.c_str(), __o.length());
88 }
89 }
90
91 [[__gnu__::__always_inline__]] inline void
92 __cow_constexpr_string_ctor(const char *__s, unsigned long __l)
93 {
94 __detail::_ZNSt12__cow_stringC2EPKcm(this, __s, __l);
95 }
96
97 [[__gnu__::__always_inline__]] inline void
98 __cow_constexpr_string_ctor(const char *__s, unsigned int __l)
99 {
100 __detail::_ZNSt12__cow_stringC2EPKcj(this, __s, __l);
101 }
102
103 [[__gnu__::__always_inline__]] inline void
104 __cow_constexpr_string_ctor(const char *__s, unsigned long long __l)
105 {
106 __detail::_ZNSt12__cow_stringC2EPKcy(this, __s, __l);
107 }
108
109 [[__gnu__::__always_inline__]] constexpr
110 __cow_constexpr_string(const char* __o)
111 {
112 if consteval {
113 _M_str = new string(__o);
114 } else {
115 __detail::_ZNSt12__cow_stringC2EPKc(this, __o);
116 }
117 }
118
119 [[__gnu__::__always_inline__]] constexpr
120 __cow_constexpr_string(const __cow_constexpr_string& __o) noexcept
121 {
122 if consteval {
123 _M_str = new string(*__o._M_str);
124 } else {
125 __detail::_ZNSt12__cow_stringC2ERKS_(this, __o);
126 }
127 }
128
129 [[__gnu__::__always_inline__]] constexpr __cow_constexpr_string&
130 operator=(const __cow_constexpr_string& __o) noexcept
131 {
132 if consteval {
133 string* __p = _M_str;
134 _M_str = new string(*__o._M_str);
135 delete __p;
136 return *this;
137 } else {
138 return __detail::_ZNSt12__cow_stringaSERKS_(this, __o);
139 }
140 }
141
142 [[__gnu__::__always_inline__]] constexpr
143 ~__cow_constexpr_string()
144 {
145 if consteval {
146 delete _M_str;
147 } else {
148 __detail::_ZNSt12__cow_stringD2Ev(this);
149 }
150 }
151
152 [[__gnu__::__always_inline__]] constexpr
153 __cow_constexpr_string(__cow_constexpr_string&& __o) noexcept
154 {
155 if consteval {
156 _M_str = new string(std::move(*__o._M_str));
157 } else {
158 __detail::_ZNSt12__cow_stringC2EOS_(this, std::move(__o));
159 }
160 }
161
162 [[__gnu__::__always_inline__]] constexpr __cow_constexpr_string&
163 operator=(__cow_constexpr_string&& __o) noexcept
164 {
165 if consteval {
166 string* __p = _M_str;
167 _M_str = new string(std::move(*__o._M_str));
168 delete __p;
169 return *this;
170 } else {
171 return __detail::_ZNSt12__cow_stringaSEOS_(this, std::move(__o));
172 }
173 }
174
175 [[__gnu__::__always_inline__]] constexpr const char*
176 c_str() const noexcept
177 {
178 if consteval {
179 return _M_str->c_str();
180 } else {
181 return __detail::_ZNKSt12__cow_string5c_strEv(this);
182 }
183 }
184 };
185
186 typedef __cow_constexpr_string __cow_string;
187#else
188 // Emulates an old COW string when the new std::string is in use.
189 struct __cow_string
190 {
191 union {
192 const char* _M_p;
193 char _M_bytes[sizeof(const char*)];
194 };
195
196 __cow_string();
197 __cow_string(const std::string&);
198 __cow_string(const char*, size_t);
199 __cow_string(const __cow_string&) _GLIBCXX_NOTHROW;
200 __cow_string& operator=(const __cow_string&) _GLIBCXX_NOTHROW;
201 ~__cow_string();
202#if __cplusplus >= 201103L
203 __cow_string(__cow_string&&) noexcept;
204 __cow_string& operator=(__cow_string&&) noexcept;
205#endif
206 };
207#endif
208
209 typedef basic_string<char> __sso_string;
210#else // _GLIBCXX_USE_CXX11_ABI
211 typedef basic_string<char> __cow_string;
212
213 // Emulates a new SSO string when the old std::string is in use.
214 struct __sso_string
215 {
216 struct __str
217 {
218 const char* _M_p;
219 size_t _M_string_length;
220 char _M_local_buf[16];
221 };
222
223 union {
224 __str _M_s;
225 char _M_bytes[sizeof(__str)];
226 };
227
228 __sso_string() _GLIBCXX_NOTHROW;
229 __sso_string(const std::string&);
230 __sso_string(const char*, size_t);
231 __sso_string(const __sso_string&);
232 __sso_string& operator=(const __sso_string&);
233 ~__sso_string();
234#if __cplusplus >= 201103L
235 __sso_string(__sso_string&&) noexcept;
236 __sso_string& operator=(__sso_string&&) noexcept;
237#endif
238 };
239#endif // _GLIBCXX_USE_CXX11_ABI
240#else // _GLIBCXX_USE_DUAL_ABI
241 typedef basic_string<char> __sso_string;
242 typedef basic_string<char> __cow_string;
243#endif
244
245 /**
246 * @addtogroup exceptions
247 * @{
248 */
249
250 /** Logic errors represent problems in the internal logic of a program;
251 * in theory, these are preventable, and even detectable before the
252 * program runs (e.g., violations of class invariants).
253 * @brief One of two subclasses of exception.
254 */
255 class logic_error : public exception
256 {
257 __cow_string _M_msg;
258
259 public:
260#if __cpp_lib_constexpr_exceptions >= 202502L
261 [[__gnu__::__gnu_inline__]]
262 constexpr inline explicit
263 logic_error(const string& __arg) _GLIBCXX_TXN_SAFE
264 : _M_msg(__arg) {}
265
266 [[__gnu__::__gnu_inline__]]
267 constexpr inline explicit
268 logic_error(const char* __arg) _GLIBCXX_TXN_SAFE
269 : _M_msg(__arg) {}
270
271 constexpr logic_error(logic_error&& __arg) noexcept = default;
272 constexpr logic_error& operator=(logic_error&& __arg) noexcept = default;
273 constexpr logic_error(const logic_error&) noexcept = default;
274 constexpr logic_error& operator=(const logic_error&) noexcept = default;
275
276 [[__gnu__::__gnu_inline__]]
277 constexpr inline virtual ~logic_error() _GLIBCXX_TXN_SAFE_DYN noexcept { }
278
279 [[__gnu__::__gnu_inline__]]
280 constexpr inline virtual const char*
281 what() const _GLIBCXX_TXN_SAFE_DYN noexcept
282 {
283 return _M_msg.c_str();
284 }
285#else
286 /** Takes a character string describing the error. */
287 explicit
288 logic_error(const string& __arg) _GLIBCXX_TXN_SAFE;
289
290#if __cplusplus >= 201103L
291 explicit
292 logic_error(const char*) _GLIBCXX_TXN_SAFE;
293
294 logic_error(logic_error&&) noexcept;
295 logic_error& operator=(logic_error&&) noexcept;
296#endif
297
298#if _GLIBCXX_USE_CXX11_ABI || _GLIBCXX_DEFINE_STDEXCEPT_COPY_OPS
299 logic_error(const logic_error&) _GLIBCXX_NOTHROW;
300 logic_error& operator=(const logic_error&) _GLIBCXX_NOTHROW;
301#elif __cplusplus >= 201103L
302 logic_error(const logic_error&) = default;
303 logic_error& operator=(const logic_error&) = default;
304#endif
305
306 virtual ~logic_error() _GLIBCXX_TXN_SAFE_DYN _GLIBCXX_NOTHROW;
307
308 /** Returns a C-style character string describing the general cause of
309 * the current error (the same string passed to the ctor). */
310 virtual const char*
311 what() const _GLIBCXX_TXN_SAFE_DYN _GLIBCXX_NOTHROW;
312#endif
313
314# ifdef _GLIBCXX_TM_TS_INTERNAL
315 friend void*
316 ::_txnal_logic_error_get_msg(void* e);
317# endif
318 };
319
320 /** Thrown by the library, or by you, to report domain errors (domain in
321 * the mathematical sense). */
322 class domain_error : public logic_error
323 {
324 public:
325#if __cpp_lib_constexpr_exceptions >= 202502L
326 [[__gnu__::__gnu_inline__]]
327 constexpr inline explicit domain_error(const string& __arg)
328 _GLIBCXX_TXN_SAFE
329 : logic_error(__arg) { }
330 [[__gnu__::__gnu_inline__]]
331 constexpr inline explicit domain_error(const char* __arg) _GLIBCXX_TXN_SAFE
332 : logic_error(__arg) { }
333 constexpr domain_error(const domain_error&) = default;
334 constexpr domain_error& operator=(const domain_error&) = default;
335 constexpr domain_error(domain_error&&) = default;
336 constexpr domain_error& operator=(domain_error&&) = default;
337 [[__gnu__::__gnu_inline__]]
338 constexpr inline virtual ~domain_error() noexcept { }
339#else
340 explicit domain_error(const string& __arg) _GLIBCXX_TXN_SAFE;
341#if __cplusplus >= 201103L
342 explicit domain_error(const char*) _GLIBCXX_TXN_SAFE;
343 domain_error(const domain_error&) = default;
344 domain_error& operator=(const domain_error&) = default;
345 domain_error(domain_error&&) = default;
346 domain_error& operator=(domain_error&&) = default;
347#endif
348 virtual ~domain_error() _GLIBCXX_NOTHROW;
349#endif
350 };
351
352 /** Thrown to report invalid arguments to functions. */
353 class invalid_argument : public logic_error
354 {
355 public:
356#if __cpp_lib_constexpr_exceptions >= 202502L
357 [[__gnu__::__gnu_inline__]]
358 constexpr inline explicit invalid_argument(const string& __arg)
359 _GLIBCXX_TXN_SAFE
360 : logic_error(__arg) { }
361 [[__gnu__::__gnu_inline__]]
362 constexpr inline explicit invalid_argument(const char* __arg)
363 _GLIBCXX_TXN_SAFE
364 : logic_error(__arg) { }
365 constexpr invalid_argument(const invalid_argument&) = default;
366 constexpr invalid_argument& operator=(const invalid_argument&) = default;
367 constexpr invalid_argument(invalid_argument&&) = default;
368 constexpr invalid_argument& operator=(invalid_argument&&) = default;
369 [[__gnu__::__gnu_inline__]]
370 constexpr inline virtual ~invalid_argument() noexcept { }
371#else
372 explicit invalid_argument(const string& __arg) _GLIBCXX_TXN_SAFE;
373#if __cplusplus >= 201103L
374 explicit invalid_argument(const char*) _GLIBCXX_TXN_SAFE;
375 invalid_argument(const invalid_argument&) = default;
376 invalid_argument& operator=(const invalid_argument&) = default;
377 invalid_argument(invalid_argument&&) = default;
378 invalid_argument& operator=(invalid_argument&&) = default;
379#endif
380 virtual ~invalid_argument() _GLIBCXX_NOTHROW;
381#endif
382 };
383
384 /** Thrown when an object is constructed that would exceed its maximum
385 * permitted size (e.g., a basic_string instance). */
386 class length_error : public logic_error
387 {
388 public:
389#if __cpp_lib_constexpr_exceptions >= 202502L
390 [[__gnu__::__gnu_inline__]]
391 constexpr inline explicit length_error(const string& __arg)
392 _GLIBCXX_TXN_SAFE
393 : logic_error(__arg) { }
394 [[__gnu__::__gnu_inline__]]
395 constexpr inline explicit length_error(const char* __arg) _GLIBCXX_TXN_SAFE
396 : logic_error(__arg) { }
397 constexpr length_error(const length_error&) = default;
398 constexpr length_error& operator=(const length_error&) = default;
399 constexpr length_error(length_error&&) = default;
400 constexpr length_error& operator=(length_error&&) = default;
401 [[__gnu__::__gnu_inline__]]
402 constexpr inline virtual ~length_error() noexcept { }
403#else
404 explicit length_error(const string& __arg) _GLIBCXX_TXN_SAFE;
405#if __cplusplus >= 201103L
406 explicit length_error(const char*) _GLIBCXX_TXN_SAFE;
407 length_error(const length_error&) = default;
408 length_error& operator=(const length_error&) = default;
409 length_error(length_error&&) = default;
410 length_error& operator=(length_error&&) = default;
411#endif
412 virtual ~length_error() _GLIBCXX_NOTHROW;
413#endif
414 };
415
416 /** This represents an argument whose value is not within the expected
417 * range (e.g., boundary checks in basic_string). */
418 class out_of_range : public logic_error
419 {
420 public:
421#if __cpp_lib_constexpr_exceptions >= 202502L
422 [[__gnu__::__gnu_inline__]]
423 constexpr inline explicit out_of_range(const string& __arg)
424 _GLIBCXX_TXN_SAFE
425 : logic_error(__arg) { }
426 [[__gnu__::__gnu_inline__]]
427 constexpr inline explicit out_of_range(const char* __arg) _GLIBCXX_TXN_SAFE
428 : logic_error(__arg) { }
429 constexpr out_of_range(const out_of_range&) = default;
430 constexpr out_of_range& operator=(const out_of_range&) = default;
431 constexpr out_of_range(out_of_range&&) = default;
432 constexpr out_of_range& operator=(out_of_range&&) = default;
433 [[__gnu__::__gnu_inline__]]
434 constexpr inline virtual ~out_of_range() noexcept { }
435#else
436 explicit out_of_range(const string& __arg) _GLIBCXX_TXN_SAFE;
437#if __cplusplus >= 201103L
438 explicit out_of_range(const char*) _GLIBCXX_TXN_SAFE;
439 out_of_range(const out_of_range&) = default;
440 out_of_range& operator=(const out_of_range&) = default;
441 out_of_range(out_of_range&&) = default;
442 out_of_range& operator=(out_of_range&&) = default;
443#endif
444 virtual ~out_of_range() _GLIBCXX_NOTHROW;
445#endif
446 };
447
448 /** Runtime errors represent problems outside the scope of a program;
449 * they cannot be easily predicted and can generally only be caught as
450 * the program executes.
451 * @brief One of two subclasses of exception.
452 */
453 class runtime_error : public exception
454 {
455 __cow_string _M_msg;
456
457 public:
458#if __cpp_lib_constexpr_exceptions >= 202502L
459 [[__gnu__::__gnu_inline__]]
460 constexpr inline explicit
461 runtime_error(const string& __arg) _GLIBCXX_TXN_SAFE
462 : _M_msg(__arg) {}
463
464 [[__gnu__::__gnu_inline__]]
465 constexpr inline explicit
466 runtime_error(const char* __arg) _GLIBCXX_TXN_SAFE
467 : _M_msg(__arg) {}
468
469 constexpr runtime_error(runtime_error&&) noexcept = default;
470 constexpr runtime_error& operator=(runtime_error&&) noexcept = default;
471 constexpr runtime_error(const runtime_error&) noexcept = default;
472 runtime_error& operator=(const runtime_error&) noexcept = default;
473
474 [[__gnu__::__gnu_inline__]]
475 constexpr inline virtual ~runtime_error() _GLIBCXX_TXN_SAFE_DYN noexcept
476 {}
477
478 [[__gnu__::__gnu_inline__]]
479 constexpr inline virtual const char*
480 what() const _GLIBCXX_TXN_SAFE_DYN noexcept
481 {
482 return _M_msg.c_str();
483 }
484#else
485 /** Takes a character string describing the error. */
486 explicit
487 runtime_error(const string& __arg) _GLIBCXX_TXN_SAFE;
488
489#if __cplusplus >= 201103L
490 explicit
491 runtime_error(const char*) _GLIBCXX_TXN_SAFE;
492
493 runtime_error(runtime_error&&) noexcept;
494 runtime_error& operator=(runtime_error&&) noexcept;
495#endif
496
497#if _GLIBCXX_USE_CXX11_ABI || _GLIBCXX_DEFINE_STDEXCEPT_COPY_OPS
498 runtime_error(const runtime_error&) _GLIBCXX_NOTHROW;
499 runtime_error& operator=(const runtime_error&) _GLIBCXX_NOTHROW;
500#elif __cplusplus >= 201103L
501 runtime_error(const runtime_error&) = default;
502 runtime_error& operator=(const runtime_error&) = default;
503#endif
504
505 virtual ~runtime_error() _GLIBCXX_TXN_SAFE_DYN _GLIBCXX_NOTHROW;
506
507 /** Returns a C-style character string describing the general cause of
508 * the current error (the same string passed to the ctor). */
509 virtual const char*
510 what() const _GLIBCXX_TXN_SAFE_DYN _GLIBCXX_NOTHROW;
511#endif
512
513# ifdef _GLIBCXX_TM_TS_INTERNAL
514 friend void*
515 ::_txnal_runtime_error_get_msg(void* e);
516# endif
517 };
518
519 /** Thrown to indicate arithmetic overflow. */
520 class overflow_error : public runtime_error
521 {
522 public:
523#if __cpp_lib_constexpr_exceptions >= 202502L
524 [[__gnu__::__gnu_inline__]]
525 constexpr inline explicit overflow_error(const string& __arg)
526 _GLIBCXX_TXN_SAFE
527 : runtime_error(__arg) { }
528 [[__gnu__::__gnu_inline__]]
529 constexpr inline explicit overflow_error(const char* __arg)
530 _GLIBCXX_TXN_SAFE
531 : runtime_error(__arg) { }
532 constexpr overflow_error(const overflow_error&) = default;
533 constexpr overflow_error& operator=(const overflow_error&) = default;
534 constexpr overflow_error(overflow_error&&) = default;
535 constexpr overflow_error& operator=(overflow_error&&) = default;
536 [[__gnu__::__gnu_inline__]]
537 constexpr inline virtual ~overflow_error() noexcept { }
538#else
539 explicit overflow_error(const string& __arg) _GLIBCXX_TXN_SAFE;
540#if __cplusplus >= 201103L
541 explicit overflow_error(const char*) _GLIBCXX_TXN_SAFE;
542 overflow_error(const overflow_error&) = default;
543 overflow_error& operator=(const overflow_error&) = default;
544 overflow_error(overflow_error&&) = default;
545 overflow_error& operator=(overflow_error&&) = default;
546#endif
547 virtual ~overflow_error() _GLIBCXX_NOTHROW;
548#endif
549 };
550
551 /** Thrown to indicate arithmetic underflow. */
552 class underflow_error : public runtime_error
553 {
554 public:
555#if __cpp_lib_constexpr_exceptions >= 202502L
556 [[__gnu__::__gnu_inline__]]
557 constexpr inline explicit underflow_error(const string& __arg)
558 _GLIBCXX_TXN_SAFE
559 : runtime_error(__arg) { }
560 [[__gnu__::__gnu_inline__]]
561 constexpr inline explicit underflow_error(const char* __arg)
562 _GLIBCXX_TXN_SAFE
563 : runtime_error(__arg) { }
564 constexpr underflow_error(const underflow_error&) = default;
565 constexpr underflow_error& operator=(const underflow_error&) = default;
566 constexpr underflow_error(underflow_error&&) = default;
567 constexpr underflow_error& operator=(underflow_error&&) = default;
568 [[__gnu__::__gnu_inline__]]
569 constexpr inline virtual ~underflow_error() noexcept { }
570#else
571 explicit underflow_error(const string& __arg) _GLIBCXX_TXN_SAFE;
572#if __cplusplus >= 201103L
573 explicit underflow_error(const char*) _GLIBCXX_TXN_SAFE;
574 underflow_error(const underflow_error&) = default;
575 underflow_error& operator=(const underflow_error&) = default;
576 underflow_error(underflow_error&&) = default;
577 underflow_error& operator=(underflow_error&&) = default;
578#endif
579 virtual ~underflow_error() _GLIBCXX_NOTHROW;
580#endif
581 };
582
583 /// @} group exceptions
584
585_GLIBCXX_END_NAMESPACE_VERSION
586} // namespace
587
588#endif /* _STDEXCEPT_EXCEPT_H */
std::move
constexpr std::remove_reference< _Tp >::type && move(_Tp &&__t) noexcept
Convert a value to an rvalue.
Definition move.h:138
std::string
basic_string< char > string
A string of char.
Definition stringfwd.h:79
std
ISO C++ entities toplevel namespace is std.
std::__detail
Implementation details not part of the namespace std interface.
std::logic_error::what
virtual const char * what() const noexcept
std::logic_error::logic_error
logic_error(const string &__arg)
std::runtime_error::runtime_error
runtime_error(const string &__arg)
std::runtime_error::what
virtual const char * what() const noexcept