< cpp‎ | error
Diagnostics library
Exception handling
Exception handling failures
(until C++17)
(until C++17)
(C++11)(until C++17)
(until C++17)
Error codes
Error codes
Defined in header <exception>
[[noreturn]] void rethrow_exception( std::exception_ptr p );
(since C++11)

Throws the previously captured exception object referred-to by the exception pointer p, or a copy of that object.

It is unspecified whether a copy is made. If a copy is made, the storage for it is allocated in an unspecified way.

The behavior is undefined if p is null.


[edit] Parameters

p - non-null std::exception_ptr

[edit] Return value


[edit] Exceptions

The exception object referred-to by p if no copy is made.

Otherwise, a copy of such exception object if the implementation successfully copied the exception object.

Otherwise, std::bad_alloc or the exception thrown when copying the exception object, if allocation or copying fails, respectively.

[edit] Notes

Before P1675R2, rethrow_exception was not allowed to copy the exception object, which is unimplementable on some platforms where exception objects are allocated on the stack.

[edit] Example

#include <iostream>
#include <string>
#include <exception>
#include <stdexcept>
void handle_eptr(std::exception_ptr eptr) // passing by value is ok
    try {
        if (eptr) {
    } catch(const std::exception& e) {
        std::cout << "Caught exception \"" << e.what() << "\"\n";
int main()
    std::exception_ptr eptr;
    try {
        std::string().at(1); // this generates an std::out_of_range
    } catch(...) {
        eptr = std::current_exception(); // capture
} // destructor for std::out_of_range called here, when the eptr is destructed

Possible output:

Caught exception "basic_string::at"

[edit] See also

shared pointer type for handling exception objects
(typedef) [edit]
captures the current exception in a std::exception_ptr
(function) [edit]