std::bad_exception

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< cpplrm; | error
Error handling
Exception handling
Exception handling failures
bad_exception
(until C++17)
(until C++17)
(C++11)(until C++17)
(until C++17)
Contracts
Defined in header <exception>
class bad_exception;

std::bad_exception is the type of the exception thrown by the C++ runtime in the following situations:

1) If std::exception_ptr stores a copy of the caught exception and if the copy constructor of the exception object caught by std::current_exception throws an exception, the captured exception is an instance of std::bad_exception.
2) If a dynamic exception specification is violated and std::unexpected throws or rethrows an exception that still violates the exception specification, but the exception specification allows std::bad_exception, std::bad_exception is thrown.
(until C++17)
cpp/error/exceptionstd-bad exception-inheritance.svg

Inheritance diagram

Member functions

constructs the bad_exception object
(public member function)
copies the object
(public member function)
[virtual]
returns the explanatory string
(virtual public member function)

Inherited from std::exception

Member functions

[virtual]
destroys the exception object
(virtual public member function of std::exception)
[virtual]
returns an explanatory string
(virtual public member function of std::exception)

Example

#include <iostream>
#include <exception>
#include <stdexcept>

void my_unexp() { throw; }

void test() throw(std::bad_exception)
{
    throw std::runtime_error("test");
}

int main()
{
    std::set_unexpected(my_unexp);
    try {
         test();
    } catch(const std::bad_exception& e)
    {
        std::cerr << "Caught " << e.what() << '\n';
    }
}

Output:

Caught std::bad_exception