Well, SDL_DestroyWindow() doesn't return bool nor a pointer. It's likely that calling SDL_GetError() right after is meaningless. If the window closes and your app ends, remove this unnecessary logging. Usually you are only supposed to use SDL_GetError() when there is an actual error, i.e. when an SDL function returns false/NULL... The documentation of DestroyWindow supports my point. Usually you will see clear mention of using GetError in the documentation if you don't see any mention of it and the function ends with void then don't use GetError.