iterator pointing to invalid container

[Parapura Rajkumar]

int main(int argc, char* argv[])
{
std::map<int, int>::iterator footest;
{
std::map<int, int> foo;
foo[0] = 0;
footest = foo.begin();
}
return 0;
}

Is this undefined behavior? Please note that footest is going out of
scope before std::map. In theory an implementation could have a
iterator destructor that could still access the std::map ?

Thanks
Raj

 

[Victor Bazarov]

int main(int argc, char* argv[])
{
std::map<int, int>::iterator footest;
{
std::map<int, int> foo;
foo[0] = 0;
footest = foo.begin();
}
return 0;
}

Is this undefined behavior? Please note that footest is going out of
scope before std::map.

You mean, "after 'foo'", don't you?

In theory an implementation could have a
iterator destructor that could still access the std::map ?

No. The iterator is allowed to be invalid, that does not affect
its destruction.

V

 

[Roland Pibinger]

int main(int argc, char* argv[])
{
std::map<int, int>::iterator footest;
{
std::map<int, int> foo;
foo[0] = 0;
footest = foo.begin();
}
return 0;
}

Is this undefined behavior? Please note that footest is going out of
scope before std::map.

You mean, "after 'foo'", don't you?

In theory an implementation could have a
iterator destructor that could still access the std::map ?

No. The iterator is allowed to be invalid, that does not affect
its destruction.

Different kinds of invalid iterators are described here:
http://www.angelikalanger.com/Conferences/Slides/CppInvalidIterators-DevConnections-2002.pdf

Best wishes,
Roland Pibinger