1int abs(int j); 2extern void abort(void); 3 4__attribute__((noinline)) int lisp_atan2(long dy, long dx) { 5 if (dx <= 0) 6 if (dy > 0) 7 return abs(dx) <= abs(dy); 8 return 0; 9} 10 11int main() { 12 volatile long dy = 63, dx = -77; 13 if (lisp_atan2(dy, dx)) 14 abort(); 15 return 0; 16} 17