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Merge libc++ trunk r300890, and update build glue.
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1 // -*- C++ -*-
2 //===---------------------------- system_error ----------------------------===//
3 //
4 //                     The LLVM Compiler Infrastructure
5 //
6 // This file is dual licensed under the MIT and the University of Illinois Open
7 // Source Licenses. See LICENSE.TXT for details.
8 //
9 //===----------------------------------------------------------------------===//
10
11 #ifndef _LIBCPP_SYSTEM_ERROR
12 #define _LIBCPP_SYSTEM_ERROR
13
14 /*
15     system_error synopsis
16
17 namespace std
18 {
19
20 class error_category
21 {
22 public:
23     virtual ~error_category() noexcept;
24
25     constexpr error_category();
26     error_category(const error_category&) = delete;
27     error_category& operator=(const error_category&) = delete;
28
29     virtual const char* name() const noexcept = 0;
30     virtual error_condition default_error_condition(int ev) const noexcept;
31     virtual bool equivalent(int code, const error_condition& condition) const noexcept;
32     virtual bool equivalent(const error_code& code, int condition) const noexcept;
33     virtual string message(int ev) const = 0;
34
35     bool operator==(const error_category& rhs) const noexcept;
36     bool operator!=(const error_category& rhs) const noexcept;
37     bool operator<(const error_category& rhs) const noexcept;
38 };
39
40 const error_category& generic_category() noexcept;
41 const error_category& system_category() noexcept;
42
43 template <class T> struct is_error_code_enum
44     : public false_type {};
45
46 template <class T> struct is_error_condition_enum
47     : public false_type {};
48
49 template <class _Tp>
50 constexpr size_t is_error_condition_enum_v = is_error_condition_enum<_Tp>::value; // C++17
51
52 template <class _Tp>
53 constexpr size_t is_error_code_enum_v = is_error_code_enum<_Tp>::value; // C++17
54
55 class error_code
56 {
57 public:
58     // constructors:
59     error_code() noexcept;
60     error_code(int val, const error_category& cat) noexcept;
61     template <class ErrorCodeEnum>
62         error_code(ErrorCodeEnum e) noexcept;
63
64     // modifiers:
65     void assign(int val, const error_category& cat) noexcept;
66     template <class ErrorCodeEnum>
67         error_code& operator=(ErrorCodeEnum e) noexcept;
68     void clear() noexcept;
69
70     // observers:
71     int value() const noexcept;
72     const error_category& category() const noexcept;
73     error_condition default_error_condition() const noexcept;
74     string message() const;
75     explicit operator bool() const noexcept;
76 };
77
78 // non-member functions:
79 bool operator<(const error_code& lhs, const error_code& rhs) noexcept;
80 template <class charT, class traits>
81     basic_ostream<charT,traits>&
82     operator<<(basic_ostream<charT,traits>& os, const error_code& ec);
83
84 class error_condition
85 {
86 public:
87     // constructors:
88     error_condition() noexcept;
89     error_condition(int val, const error_category& cat) noexcept;
90     template <class ErrorConditionEnum>
91         error_condition(ErrorConditionEnum e) noexcept;
92
93     // modifiers:
94     void assign(int val, const error_category& cat) noexcept;
95     template <class ErrorConditionEnum>
96         error_condition& operator=(ErrorConditionEnum e) noexcept;
97     void clear() noexcept;
98
99     // observers:
100     int value() const noexcept;
101     const error_category& category() const noexcept;
102     string message() const noexcept;
103     explicit operator bool() const noexcept;
104 };
105
106 bool operator<(const error_condition& lhs, const error_condition& rhs) noexcept;
107
108 class system_error
109     : public runtime_error
110 {
111 public:
112     system_error(error_code ec, const string& what_arg);
113     system_error(error_code ec, const char* what_arg);
114     system_error(error_code ec);
115     system_error(int ev, const error_category& ecat, const string& what_arg);
116     system_error(int ev, const error_category& ecat, const char* what_arg);
117     system_error(int ev, const error_category& ecat);
118
119     const error_code& code() const noexcept;
120     const char* what() const noexcept;
121 };
122
123 enum class errc
124 {
125     address_family_not_supported,       // EAFNOSUPPORT
126     address_in_use,                     // EADDRINUSE
127     address_not_available,              // EADDRNOTAVAIL
128     already_connected,                  // EISCONN
129     argument_list_too_long,             // E2BIG
130     argument_out_of_domain,             // EDOM
131     bad_address,                        // EFAULT
132     bad_file_descriptor,                // EBADF
133     bad_message,                        // EBADMSG
134     broken_pipe,                        // EPIPE
135     connection_aborted,                 // ECONNABORTED
136     connection_already_in_progress,     // EALREADY
137     connection_refused,                 // ECONNREFUSED
138     connection_reset,                   // ECONNRESET
139     cross_device_link,                  // EXDEV
140     destination_address_required,       // EDESTADDRREQ
141     device_or_resource_busy,            // EBUSY
142     directory_not_empty,                // ENOTEMPTY
143     executable_format_error,            // ENOEXEC
144     file_exists,                        // EEXIST
145     file_too_large,                     // EFBIG
146     filename_too_long,                  // ENAMETOOLONG
147     function_not_supported,             // ENOSYS
148     host_unreachable,                   // EHOSTUNREACH
149     identifier_removed,                 // EIDRM
150     illegal_byte_sequence,              // EILSEQ
151     inappropriate_io_control_operation, // ENOTTY
152     interrupted,                        // EINTR
153     invalid_argument,                   // EINVAL
154     invalid_seek,                       // ESPIPE
155     io_error,                           // EIO
156     is_a_directory,                     // EISDIR
157     message_size,                       // EMSGSIZE
158     network_down,                       // ENETDOWN
159     network_reset,                      // ENETRESET
160     network_unreachable,                // ENETUNREACH
161     no_buffer_space,                    // ENOBUFS
162     no_child_process,                   // ECHILD
163     no_link,                            // ENOLINK
164     no_lock_available,                  // ENOLCK
165     no_message_available,               // ENODATA
166     no_message,                         // ENOMSG
167     no_protocol_option,                 // ENOPROTOOPT
168     no_space_on_device,                 // ENOSPC
169     no_stream_resources,                // ENOSR
170     no_such_device_or_address,          // ENXIO
171     no_such_device,                     // ENODEV
172     no_such_file_or_directory,          // ENOENT
173     no_such_process,                    // ESRCH
174     not_a_directory,                    // ENOTDIR
175     not_a_socket,                       // ENOTSOCK
176     not_a_stream,                       // ENOSTR
177     not_connected,                      // ENOTCONN
178     not_enough_memory,                  // ENOMEM
179     not_supported,                      // ENOTSUP
180     operation_canceled,                 // ECANCELED
181     operation_in_progress,              // EINPROGRESS
182     operation_not_permitted,            // EPERM
183     operation_not_supported,            // EOPNOTSUPP
184     operation_would_block,              // EWOULDBLOCK
185     owner_dead,                         // EOWNERDEAD
186     permission_denied,                  // EACCES
187     protocol_error,                     // EPROTO
188     protocol_not_supported,             // EPROTONOSUPPORT
189     read_only_file_system,              // EROFS
190     resource_deadlock_would_occur,      // EDEADLK
191     resource_unavailable_try_again,     // EAGAIN
192     result_out_of_range,                // ERANGE
193     state_not_recoverable,              // ENOTRECOVERABLE
194     stream_timeout,                     // ETIME
195     text_file_busy,                     // ETXTBSY
196     timed_out,                          // ETIMEDOUT
197     too_many_files_open_in_system,      // ENFILE
198     too_many_files_open,                // EMFILE
199     too_many_links,                     // EMLINK
200     too_many_symbolic_link_levels,      // ELOOP
201     value_too_large,                    // EOVERFLOW
202     wrong_protocol_type                 // EPROTOTYPE
203 };
204
205 template <> struct is_error_condition_enum<errc>
206     : true_type { }
207
208 error_code make_error_code(errc e) noexcept;
209 error_condition make_error_condition(errc e) noexcept;
210
211 // Comparison operators:
212 bool operator==(const error_code& lhs, const error_code& rhs) noexcept;
213 bool operator==(const error_code& lhs, const error_condition& rhs) noexcept;
214 bool operator==(const error_condition& lhs, const error_code& rhs) noexcept;
215 bool operator==(const error_condition& lhs, const error_condition& rhs) noexcept;
216 bool operator!=(const error_code& lhs, const error_code& rhs) noexcept;
217 bool operator!=(const error_code& lhs, const error_condition& rhs) noexcept;
218 bool operator!=(const error_condition& lhs, const error_code& rhs) noexcept;
219 bool operator!=(const error_condition& lhs, const error_condition& rhs) noexcept;
220
221 template <> struct hash<std::error_code>;
222 template <> struct hash<std::error_condition>;
223
224 }  // std
225
226 */
227
228 #include <__config>
229 #include <cerrno>
230 #include <type_traits>
231 #include <stdexcept>
232 #include <__functional_base>
233
234 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
235 #pragma GCC system_header
236 #endif
237
238 _LIBCPP_BEGIN_NAMESPACE_STD
239
240 // is_error_code_enum
241
242 template <class _Tp>
243 struct _LIBCPP_TEMPLATE_VIS is_error_code_enum
244     : public false_type {};
245
246 #if _LIBCPP_STD_VER > 14
247 template <class _Tp>
248 constexpr size_t is_error_code_enum_v = is_error_code_enum<_Tp>::value;
249 #endif
250
251 // is_error_condition_enum
252
253 template <class _Tp>
254 struct _LIBCPP_TEMPLATE_VIS is_error_condition_enum
255     : public false_type {};
256
257 #if _LIBCPP_STD_VER > 14
258 template <class _Tp>
259 constexpr size_t is_error_condition_enum_v = is_error_condition_enum<_Tp>::value;
260 #endif
261
262 // Some error codes are not present on all platforms, so we provide equivalents
263 // for them:
264
265 //enum class errc
266 _LIBCPP_DECLARE_STRONG_ENUM(errc)
267 {
268     address_family_not_supported        = EAFNOSUPPORT,
269     address_in_use                      = EADDRINUSE,
270     address_not_available               = EADDRNOTAVAIL,
271     already_connected                   = EISCONN,
272     argument_list_too_long              = E2BIG,
273     argument_out_of_domain              = EDOM,
274     bad_address                         = EFAULT,
275     bad_file_descriptor                 = EBADF,
276     bad_message                         = EBADMSG,
277     broken_pipe                         = EPIPE,
278     connection_aborted                  = ECONNABORTED,
279     connection_already_in_progress      = EALREADY,
280     connection_refused                  = ECONNREFUSED,
281     connection_reset                    = ECONNRESET,
282     cross_device_link                   = EXDEV,
283     destination_address_required        = EDESTADDRREQ,
284     device_or_resource_busy             = EBUSY,
285     directory_not_empty                 = ENOTEMPTY,
286     executable_format_error             = ENOEXEC,
287     file_exists                         = EEXIST,
288     file_too_large                      = EFBIG,
289     filename_too_long                   = ENAMETOOLONG,
290     function_not_supported              = ENOSYS,
291     host_unreachable                    = EHOSTUNREACH,
292     identifier_removed                  = EIDRM,
293     illegal_byte_sequence               = EILSEQ,
294     inappropriate_io_control_operation  = ENOTTY,
295     interrupted                         = EINTR,
296     invalid_argument                    = EINVAL,
297     invalid_seek                        = ESPIPE,
298     io_error                            = EIO,
299     is_a_directory                      = EISDIR,
300     message_size                        = EMSGSIZE,
301     network_down                        = ENETDOWN,
302     network_reset                       = ENETRESET,
303     network_unreachable                 = ENETUNREACH,
304     no_buffer_space                     = ENOBUFS,
305     no_child_process                    = ECHILD,
306     no_link                             = ENOLINK,
307     no_lock_available                   = ENOLCK,
308 #ifdef ENODATA
309     no_message_available                = ENODATA,
310 #else
311     no_message_available                = ENOMSG,
312 #endif
313     no_message                          = ENOMSG,
314     no_protocol_option                  = ENOPROTOOPT,
315     no_space_on_device                  = ENOSPC,
316 #ifdef ENOSR
317     no_stream_resources                 = ENOSR,
318 #else
319     no_stream_resources                 = ENOMEM,
320 #endif
321     no_such_device_or_address           = ENXIO,
322     no_such_device                      = ENODEV,
323     no_such_file_or_directory           = ENOENT,
324     no_such_process                     = ESRCH,
325     not_a_directory                     = ENOTDIR,
326     not_a_socket                        = ENOTSOCK,
327 #ifdef ENOSTR
328     not_a_stream                        = ENOSTR,
329 #else
330     not_a_stream                        = EINVAL,
331 #endif
332     not_connected                       = ENOTCONN,
333     not_enough_memory                   = ENOMEM,
334     not_supported                       = ENOTSUP,
335     operation_canceled                  = ECANCELED,
336     operation_in_progress               = EINPROGRESS,
337     operation_not_permitted             = EPERM,
338     operation_not_supported             = EOPNOTSUPP,
339     operation_would_block               = EWOULDBLOCK,
340     owner_dead                          = EOWNERDEAD,
341     permission_denied                   = EACCES,
342     protocol_error                      = EPROTO,
343     protocol_not_supported              = EPROTONOSUPPORT,
344     read_only_file_system               = EROFS,
345     resource_deadlock_would_occur       = EDEADLK,
346     resource_unavailable_try_again      = EAGAIN,
347     result_out_of_range                 = ERANGE,
348     state_not_recoverable               = ENOTRECOVERABLE,
349 #ifdef ETIME
350     stream_timeout                      = ETIME,
351 #else
352     stream_timeout                      = ETIMEDOUT,
353 #endif
354     text_file_busy                      = ETXTBSY,
355     timed_out                           = ETIMEDOUT,
356     too_many_files_open_in_system       = ENFILE,
357     too_many_files_open                 = EMFILE,
358     too_many_links                      = EMLINK,
359     too_many_symbolic_link_levels       = ELOOP,
360     value_too_large                     = EOVERFLOW,
361     wrong_protocol_type                 = EPROTOTYPE
362 };
363 _LIBCPP_DECLARE_STRONG_ENUM_EPILOG(errc)
364
365 template <>
366 struct _LIBCPP_TEMPLATE_VIS is_error_condition_enum<errc>
367     : true_type { };
368
369 #ifdef _LIBCPP_HAS_NO_STRONG_ENUMS
370 template <>
371 struct _LIBCPP_TEMPLATE_VIS is_error_condition_enum<errc::__lx>
372     : true_type { };
373 #endif
374
375 class _LIBCPP_TYPE_VIS error_condition;
376 class _LIBCPP_TYPE_VIS error_code;
377
378 // class error_category
379
380 class _LIBCPP_HIDDEN __do_message;
381
382 class _LIBCPP_TYPE_VIS error_category
383 {
384 public:
385     virtual ~error_category() _NOEXCEPT;
386
387 #if defined(_LIBCPP_BUILDING_SYSTEM_ERROR) && \
388     defined(_LIBCPP_DEPRECATED_ABI_LEGACY_LIBRARY_DEFINITIONS_FOR_INLINE_FUNCTIONS)
389     error_category() _NOEXCEPT;
390 #else
391     _LIBCPP_ALWAYS_INLINE
392     _LIBCPP_CONSTEXPR_AFTER_CXX11 error_category() _NOEXCEPT _LIBCPP_DEFAULT
393 #endif
394 private:
395     error_category(const error_category&);// = delete;
396     error_category& operator=(const error_category&);// = delete;
397
398 public:
399     virtual const char* name() const _NOEXCEPT = 0;
400     virtual error_condition default_error_condition(int __ev) const _NOEXCEPT;
401     virtual bool equivalent(int __code, const error_condition& __condition) const _NOEXCEPT;
402     virtual bool equivalent(const error_code& __code, int __condition) const _NOEXCEPT;
403     virtual string message(int __ev) const = 0;
404
405     _LIBCPP_ALWAYS_INLINE
406     bool operator==(const error_category& __rhs) const _NOEXCEPT {return this == &__rhs;}
407
408     _LIBCPP_ALWAYS_INLINE
409     bool operator!=(const error_category& __rhs) const _NOEXCEPT {return !(*this == __rhs);}
410
411     _LIBCPP_ALWAYS_INLINE
412     bool operator< (const error_category& __rhs) const _NOEXCEPT {return this < &__rhs;}
413
414     friend class _LIBCPP_HIDDEN __do_message;
415 };
416
417 class _LIBCPP_HIDDEN __do_message
418     : public error_category
419 {
420 public:
421     virtual string message(int ev) const;
422 };
423
424 _LIBCPP_FUNC_VIS const error_category& generic_category() _NOEXCEPT;
425 _LIBCPP_FUNC_VIS const error_category& system_category() _NOEXCEPT;
426
427 class _LIBCPP_TYPE_VIS error_condition
428 {
429     int __val_;
430     const error_category* __cat_;
431 public:
432     _LIBCPP_ALWAYS_INLINE
433     error_condition() _NOEXCEPT : __val_(0), __cat_(&generic_category()) {}
434
435     _LIBCPP_ALWAYS_INLINE
436     error_condition(int __val, const error_category& __cat) _NOEXCEPT
437         : __val_(__val), __cat_(&__cat) {}
438
439     template <class _Ep>
440         _LIBCPP_ALWAYS_INLINE
441         error_condition(_Ep __e,
442               typename enable_if<is_error_condition_enum<_Ep>::value>::type* = 0
443                                                                      ) _NOEXCEPT
444             {*this = make_error_condition(__e);}
445
446     _LIBCPP_ALWAYS_INLINE
447     void assign(int __val, const error_category& __cat) _NOEXCEPT
448     {
449         __val_ = __val;
450         __cat_ = &__cat;
451     }
452
453     template <class _Ep>
454         _LIBCPP_ALWAYS_INLINE
455         typename enable_if
456         <
457             is_error_condition_enum<_Ep>::value,
458             error_condition&
459         >::type
460         operator=(_Ep __e) _NOEXCEPT
461             {*this = make_error_condition(__e); return *this;}
462
463     _LIBCPP_ALWAYS_INLINE
464     void clear() _NOEXCEPT
465     {
466         __val_ = 0;
467         __cat_ = &generic_category();
468     }
469
470     _LIBCPP_ALWAYS_INLINE
471     int value() const _NOEXCEPT {return __val_;}
472
473     _LIBCPP_ALWAYS_INLINE
474     const error_category& category() const _NOEXCEPT {return *__cat_;}
475     string message() const;
476
477     _LIBCPP_ALWAYS_INLINE
478         _LIBCPP_EXPLICIT
479         operator bool() const _NOEXCEPT {return __val_ != 0;}
480 };
481
482 inline _LIBCPP_INLINE_VISIBILITY
483 error_condition
484 make_error_condition(errc __e) _NOEXCEPT
485 {
486     return error_condition(static_cast<int>(__e), generic_category());
487 }
488
489 inline _LIBCPP_INLINE_VISIBILITY
490 bool
491 operator<(const error_condition& __x, const error_condition& __y) _NOEXCEPT
492 {
493     return __x.category() < __y.category()
494         || (__x.category() == __y.category() && __x.value() < __y.value());
495 }
496
497 // error_code
498
499 class _LIBCPP_TYPE_VIS error_code
500 {
501     int __val_;
502     const error_category* __cat_;
503 public:
504     _LIBCPP_ALWAYS_INLINE
505     error_code() _NOEXCEPT : __val_(0), __cat_(&system_category()) {}
506
507     _LIBCPP_ALWAYS_INLINE
508     error_code(int __val, const error_category& __cat) _NOEXCEPT
509         : __val_(__val), __cat_(&__cat) {}
510
511     template <class _Ep>
512         _LIBCPP_ALWAYS_INLINE
513         error_code(_Ep __e,
514                    typename enable_if<is_error_code_enum<_Ep>::value>::type* = 0
515                                                                      ) _NOEXCEPT
516             {*this = make_error_code(__e);}
517
518     _LIBCPP_ALWAYS_INLINE
519     void assign(int __val, const error_category& __cat) _NOEXCEPT
520     {
521         __val_ = __val;
522         __cat_ = &__cat;
523     }
524
525     template <class _Ep>
526         _LIBCPP_ALWAYS_INLINE
527         typename enable_if
528         <
529             is_error_code_enum<_Ep>::value,
530             error_code&
531         >::type
532         operator=(_Ep __e) _NOEXCEPT
533             {*this = make_error_code(__e); return *this;}
534
535     _LIBCPP_ALWAYS_INLINE
536     void clear() _NOEXCEPT
537     {
538         __val_ = 0;
539         __cat_ = &system_category();
540     }
541
542     _LIBCPP_ALWAYS_INLINE
543     int value() const _NOEXCEPT {return __val_;}
544
545     _LIBCPP_ALWAYS_INLINE
546     const error_category& category() const _NOEXCEPT {return *__cat_;}
547
548     _LIBCPP_ALWAYS_INLINE
549     error_condition default_error_condition() const _NOEXCEPT
550         {return __cat_->default_error_condition(__val_);}
551
552     string message() const;
553
554     _LIBCPP_ALWAYS_INLINE
555         _LIBCPP_EXPLICIT
556         operator bool() const _NOEXCEPT {return __val_ != 0;}
557 };
558
559 inline _LIBCPP_INLINE_VISIBILITY
560 error_code
561 make_error_code(errc __e) _NOEXCEPT
562 {
563     return error_code(static_cast<int>(__e), generic_category());
564 }
565
566 inline _LIBCPP_INLINE_VISIBILITY
567 bool
568 operator<(const error_code& __x, const error_code& __y) _NOEXCEPT
569 {
570     return __x.category() < __y.category()
571         || (__x.category() == __y.category() && __x.value() < __y.value());
572 }
573
574 inline _LIBCPP_INLINE_VISIBILITY
575 bool
576 operator==(const error_code& __x, const error_code& __y) _NOEXCEPT
577 {
578     return __x.category() == __y.category() && __x.value() == __y.value();
579 }
580
581 inline _LIBCPP_INLINE_VISIBILITY
582 bool
583 operator==(const error_code& __x, const error_condition& __y) _NOEXCEPT
584 {
585     return __x.category().equivalent(__x.value(), __y)
586         || __y.category().equivalent(__x, __y.value());
587 }
588
589 inline _LIBCPP_INLINE_VISIBILITY
590 bool
591 operator==(const error_condition& __x, const error_code& __y) _NOEXCEPT
592 {
593     return __y == __x;
594 }
595
596 inline _LIBCPP_INLINE_VISIBILITY
597 bool
598 operator==(const error_condition& __x, const error_condition& __y) _NOEXCEPT
599 {
600     return __x.category() == __y.category() && __x.value() == __y.value();
601 }
602
603 inline _LIBCPP_INLINE_VISIBILITY
604 bool
605 operator!=(const error_code& __x, const error_code& __y) _NOEXCEPT
606 {return !(__x == __y);}
607
608 inline _LIBCPP_INLINE_VISIBILITY
609 bool
610 operator!=(const error_code& __x, const error_condition& __y) _NOEXCEPT
611 {return !(__x == __y);}
612
613 inline _LIBCPP_INLINE_VISIBILITY
614 bool
615 operator!=(const error_condition& __x, const error_code& __y) _NOEXCEPT
616 {return !(__x == __y);}
617
618 inline _LIBCPP_INLINE_VISIBILITY
619 bool
620 operator!=(const error_condition& __x, const error_condition& __y) _NOEXCEPT
621 {return !(__x == __y);}
622
623 template <>
624 struct _LIBCPP_TEMPLATE_VIS hash<error_code>
625     : public unary_function<error_code, size_t>
626 {
627     _LIBCPP_INLINE_VISIBILITY
628     size_t operator()(const error_code& __ec) const _NOEXCEPT
629     {
630         return static_cast<size_t>(__ec.value());
631     }
632 };
633
634 template <>
635 struct _LIBCPP_TEMPLATE_VIS hash<error_condition>
636     : public unary_function<error_condition, size_t>
637 {
638     _LIBCPP_INLINE_VISIBILITY
639     size_t operator()(const error_condition& __ec) const _NOEXCEPT
640     {
641         return static_cast<size_t>(__ec.value());
642     }
643 };
644
645 // system_error
646
647 class _LIBCPP_TYPE_VIS system_error
648     : public runtime_error
649 {
650     error_code __ec_;
651 public:
652     system_error(error_code __ec, const string& __what_arg);
653     system_error(error_code __ec, const char* __what_arg);
654     system_error(error_code __ec);
655     system_error(int __ev, const error_category& __ecat, const string& __what_arg);
656     system_error(int __ev, const error_category& __ecat, const char* __what_arg);
657     system_error(int __ev, const error_category& __ecat);
658     ~system_error() _NOEXCEPT;
659
660     _LIBCPP_ALWAYS_INLINE
661     const error_code& code() const _NOEXCEPT {return __ec_;}
662
663 private:
664     static string __init(const error_code&, string);
665 };
666
667 _LIBCPP_NORETURN _LIBCPP_FUNC_VIS
668 void __throw_system_error(int ev, const char* what_arg);
669
670 _LIBCPP_END_NAMESPACE_STD
671
672 #endif  // _LIBCPP_SYSTEM_ERROR