The asteroid iteration loop

for (auto asteroid = m_asteroidData.begin(); asteroid != m_asteroidData.end(); asteroid++)

can have some problems with the iterator asteroid being invalidated. Specifically while adding asteroids with

m_asteroidData.push_back(data);

If the adding of the additional data results in vector reallocation, all iterators are invalidated, and an exception can be triggered by next access of asteroid.

I ran into this problem when firing a lot of bullets and when keeping the asteroids created when hit with a bullet around.

I solved this problem by adding new asteroids to a separate vector, which is then safely dumped into the main vector after the entire asteroid loop is complete.

I also changed the standard iteration to a while loop form

auto asteroid = m_asteroidData.begin();
while(asteroid != m_asteroidData.end())

To avoid checking

if (asteroid == m_asteroidData.end())
break;

on each erasure (only checked on the end of the loop where I do asteroid++), though I don't think that should have any affect on this issue.