1 extern void abort(void); 2 extern void exit(int); 3 foo(unsigned int a)4 unsigned int foo(unsigned int a) 5 { 6 return ((unsigned char)(a + 1)) * 4; 7 } 8 main(void)9 int main(void) 10 { 11 if (foo((unsigned char)~0)) 12 abort (); 13 exit(0); 14 } 15