1 int val; 2 3 int *ptr = &val; 4 float *ptr2 = &val; 5 6 __attribute__((optimize ("-fno-strict-aliasing"))) typepun()7 typepun () 8 { 9 *ptr2=0; 10 } 11 main()12 main() 13 { 14 *ptr=1; 15 typepun (); 16 if (*ptr) 17 __builtin_abort (); 18 } 19 20