Is pu****ng into reserved space invalidating iterators?

Hi,

Is the following code legal?
I'm asking since the iterator debugging facility of VC++2005's stl
gives an assertion failed at runtime.

#include <vector>

int main(int argc, char** argv)
{
     std::vector<int> x;
     x.reserve(1);
     std::vector<int>::iterator i = x.end();
     x.push_back(1); // No reallocation
     if ( i != x.end()) // Debug Assertion failed: iterators
incompatible?
         return *i; // Debug Assertion failed: vector iterator not
dereferencable?
}

I had understood that iterators only become invalid when vector
operations cause reallocation.

Maarten Hilferink

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