My game is pointer erroring at the return 0; at the end of the main loop.
The code i just added destroys some BITMAPs (as far as I can tell they are not used after this).

But why would it pointer error there?

Well i wouldn't have a clue waht to show you:

main:

int main() {
  init();

  while (run) loop();

  deinit();
  return 0;
}

That's a bit useless.

You see the problem occurs at return 0; So where am i supposed to show you?

loop:

void loop(){
     if (key[KEY_ESC]) game_exit();
     if (room == cRoom->id){
        cRoom->constructor();
        while (room == cRoom->id){allrooms(); cRoom->exec(); }
        cRoom->destructor();
     }
     else cRoom = rooms[room - 1];
}

The current constructor exec and destructor:

It was those destroy_bitmaps() that I added as I realised I'd forgotten to do that.
I also moved the load_bitmap s from the load_bitmaps() function into there, so it's easier to see what I'm working with.

Are you destroying all the bitmaps, like sbuffer?

It's this:
Make sure that you're not destroying any bitmaps in global objects destructors.
I haven't checked it yet, but I just realised that the destructor function is run twice. The second time in the return 0; This is because it's run inside a class destructor.