Difference between revisions of "cpp/error/terminate"
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{{cpp/error/navbar}} | {{cpp/error/navbar}} | ||
{{dcl begin}} | {{dcl begin}} | ||
− | {{dcl header | exception}} | + | {{dcl header|exception}} |
− | {{dcl rev | + | {{dcl rev multi |
− | + | |dcl1= | |
void terminate(); | void terminate(); | ||
+ | |since2=c++11|dcl2= | ||
+ | [[noreturn]] void terminate() noexcept; | ||
}} | }} | ||
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{{dcl end}} | {{dcl end}} | ||
− | {{tt|std::terminate()}} is called by the C++ runtime when | + | {{tt|std::terminate()}} is called by the C++ runtime when the program cannot continue for any of the following reasons: |
− | @1@ | + | @1@ An [[cpp/language/throw|exception is thrown]] and not caught (it is implementation-defined whether any stack unwinding is done in this case). |
− | @2@ an exception | + | @2@ A function directly invoked by the exception handling mechanism while handling an exception that has not yet been caught exits via an exception (e.g. a destructor of some local object, or a copy constructor constructing a catch-clause parameter). |
− | @3@ | + | @3@ The constructor or the destructor of a static {{rev inl|since=c++11|or thread-local}} object throws an exception. |
− | @4@ | + | @4@ A function registered with {{lc|std::atexit}} {{rev inl|since=c++11|or {{lc|std::at_quick_exit}}}} throws an exception. |
− | @5@ | + | {{rrev|until=c++17| |
+ | @5@ A [[cpp/language/except spec|dynamic exception specification]] is violated and the default handler for {{lc|std::unexpected}} is executed. | ||
− | + | @6@ A non-default handler for {{lc|std::unexpected}} throws an exception that violates the previously violated dynamic exception specification, if the specification does not include {{lc|std::bad_exception}}. | |
− | + | ||
− | @6@ | + | |
− | + | ||
− | + | ||
}} | }} | ||
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− | + | {{rrev|since=c++11| | |
+ | @7@ A [[cpp/language/noexcept spec|noexcept specification]] is violated (it is implementation-defined whether any stack unwinding is done in this case). | ||
− | @ | + | @8@ {{lc|std::nested_exception::rethrow_nested}} is called for an object that isn't holding a captured exception. |
− | @ | + | @9@ An exception is thrown from the initial function of {{lc|std::thread}}. |
− | {{ | + | @10@ A joinable {{lc|std::thread}} is destroyed or assigned to. |
− | {{ | + | |
− | @ | + | @11@ {{lc|std::condition_variable::wait}}, {{lc|std::condition_variable::wait_until}}, or {{lc|std::condition_variable::wait_for}} fails to reach its postcondition (e.g. if relocking the mutex throws).<!-- LWG 2135 --> |
+ | }} | ||
+ | |||
+ | {{rrev|since=c++17| | ||
+ | @12@ A function invoked by a [[cpp/algorithm|parallel algorithm]] exits via an uncaught exception and the [[cpp/algorithm/execution_policy_tag_t|execution policy]] specifies termination. | ||
}} | }} | ||
− | |||
{{tt|std::terminate()}} may also be called directly from the program. | {{tt|std::terminate()}} may also be called directly from the program. | ||
+ | When {{tt|std::terminate}} is called due to a thrown exception, an implicit try/catch handler is considered active. Thus, calling {{lc|std::current_exception}} will return the thrown exception. | ||
In any case, {{tt|std::terminate}} calls the currently installed {{lc|std::terminate_handler}}. The default {{lc|std::terminate_handler}} calls {{lc|std::abort}}. | In any case, {{tt|std::terminate}} calls the currently installed {{lc|std::terminate_handler}}. The default {{lc|std::terminate_handler}} calls {{lc|std::abort}}. | ||
− | {{ | + | {{rrev multi |
− | + | |rev1= | |
If a destructor reset the terminate handler during stack unwinding and the unwinding later led to {{tt|terminate}} being called, the handler that was installed at the end of the throw expression is the one that will be called. (note: it was ambiguous whether re-throwing applied the new handlers) | If a destructor reset the terminate handler during stack unwinding and the unwinding later led to {{tt|terminate}} being called, the handler that was installed at the end of the throw expression is the one that will be called. (note: it was ambiguous whether re-throwing applied the new handlers) | ||
− | + | |since2=c++11|rev2= | |
− | + | ||
If a destructor reset the terminate handler during stack unwinding, it is unspecified which handler is called if the unwinding later led to {{tt|terminate}} being called. | If a destructor reset the terminate handler during stack unwinding, it is unspecified which handler is called if the unwinding later led to {{tt|terminate}} being called. | ||
}} | }} | ||
− | |||
− | === | + | ===Notes=== |
− | + | If the handler mechanism is not wanted, e.g. because it requires atomic operations which may bloat binary size, a direct call to {{lc|std::abort}} is preferred when terminating the program abnormally. | |
− | = | + | Some compiler intrinsics, e.g. [https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html {{tt|__builtin_trap}}] (gcc, clang, and icc) or [https://docs.microsoft.com/en-us/cpp/intrinsics/debugbreak?view=msvc-160 {{tt|__debugbreak}}] (msvc), can be used to terminate the program as fast as possible. |
− | ( | + | |
− | === | + | ===Defect reports=== |
− | {{ | + | {{dr list begin}} |
− | {{ | + | {{dr list item|wg=lwg|dr=2111|std=C++11|before=effect of calling {{lc|std::set_terminate}} during stack<br>unwinding differs from C++98 and breaks some ABIs|after=made unspecified}} |
− | + | {{dr list end}} | |
− | {{ | + | |
===See also=== | ===See also=== | ||
{{dsc begin}} | {{dsc begin}} | ||
− | {{dsc inc | cpp/error/dsc terminate_handler}} | + | {{dsc inc|cpp/error/dsc terminate_handler}} |
+ | {{dsc inc|cpp/utility/program/dsc abort}} | ||
+ | {{dsc inc|cpp/utility/dsc breakpoint}} | ||
{{dsc end}} | {{dsc end}} | ||
− | + | {{langlinks|de|es|fr|it|ja|pt|ru|zh}} | |
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Latest revision as of 09:57, 9 July 2024
Defined in header <exception>
|
||
void terminate(); |
(until C++11) | |
[[noreturn]] void terminate() noexcept; |
(since C++11) | |
std::terminate()
is called by the C++ runtime when the program cannot continue for any of the following reasons:
5) A dynamic exception specification is violated and the default handler for std::unexpected is executed.
6) A non-default handler for std::unexpected throws an exception that violates the previously violated dynamic exception specification, if the specification does not include std::bad_exception.
|
(until C++17) |
7) A noexcept specification is violated (it is implementation-defined whether any stack unwinding is done in this case).
8) std::nested_exception::rethrow_nested is called for an object that isn't holding a captured exception.
9) An exception is thrown from the initial function of std::thread.
10) A joinable std::thread is destroyed or assigned to.
11) std::condition_variable::wait, std::condition_variable::wait_until, or std::condition_variable::wait_for fails to reach its postcondition (e.g. if relocking the mutex throws).
|
(since C++11) |
12) A function invoked by a parallel algorithm exits via an uncaught exception and the execution policy specifies termination.
|
(since C++17) |
std::terminate()
may also be called directly from the program.
When std::terminate
is called due to a thrown exception, an implicit try/catch handler is considered active. Thus, calling std::current_exception will return the thrown exception.
In any case, std::terminate
calls the currently installed std::terminate_handler. The default std::terminate_handler calls std::abort.
If a destructor reset the terminate handler during stack unwinding and the unwinding later led to |
(until C++11) |
If a destructor reset the terminate handler during stack unwinding, it is unspecified which handler is called if the unwinding later led to |
(since C++11) |
[edit] Notes
If the handler mechanism is not wanted, e.g. because it requires atomic operations which may bloat binary size, a direct call to std::abort is preferred when terminating the program abnormally.
Some compiler intrinsics, e.g. __builtin_trap
(gcc, clang, and icc) or __debugbreak
(msvc), can be used to terminate the program as fast as possible.
[edit] Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
DR | Applied to | Behavior as published | Correct behavior |
---|---|---|---|
LWG 2111 | C++11 | effect of calling std::set_terminate during stack unwinding differs from C++98 and breaks some ABIs |
made unspecified |
[edit] See also
the type of the function called by std::terminate (typedef) | |
causes abnormal program termination (without cleaning up) (function) | |
(C++26) |
pauses the running program when called (function) |