Compilers will do the "wrong" thing. For example, gcc optimizes out the "x >= 0" check in for (int x = 0; x >= 0; x++) making it an infinite loop, because

Compilers will do the "wrong" thing. For example, gcc optimizes out the "x >= 0" check in for (int x = 0; x >= 0; x++) making it an infinite loop, because it assumes "x++" can't overflow.