Weird XOR swap behavior while zeroing out data

Question

Thanks Doug. Here\'s the fix:

void swap(int& a, int& b) {
    if (&a == &b) // added this check to ensure the same address is not passed in
              


        

Answer 1

In addition to the existing answers, I'll just add that if you're going to do a test before swapping then you might as well change:

if (&a == &b) // added this check to ensure the same address is not passed in
    return;

to:

if (a == b) // check that values are different
    return;

This will handle the case where &a == &b and also the case where a == b, which may save some unnecessary swapping.