modernc.org/ccgo/v3@v3.16.14/lib/testdata/gcc-9.1.0/gcc/testsuite/gcc.c-torture/execute/20001228-1.c (about) 1 int foo1(void) 2 { 3 union { 4 char a[sizeof (unsigned)]; 5 unsigned b; 6 } u; 7 8 u.b = 0x01; 9 return u.a[0]; 10 } 11 12 int foo2(void) 13 { 14 volatile union { 15 char a[sizeof (unsigned)]; 16 unsigned b; 17 } u; 18 19 u.b = 0x01; 20 return u.a[0]; 21 } 22 23 int main(void) 24 { 25 if (foo1() != foo2()) 26 abort (); 27 exit (0); 28 }