#include <iostream>

int& foo()
{
    int i = 6;
    std::cout << &i << std::endl;
    return i;
}

int main()
{
    int i = foo();
    std::cout << &i << std::endl;
}

I know it doesn't return the address of local variable so that is why the warning but why does it still works and assign the variable i in main() to '6'? How does it only return the value if the variable the was removed from stack memory?