1  struct S { char c; char arr[4]; float f; };
       2  
       3  char A[4] = { '1', '2', '3', '4' };
       4  
       5  void foo (struct S s)
       6  {
       7    if (__builtin_memcmp (s.arr, A, 4))
       8      __builtin_abort ();
       9  }
      10  
      11  int main (void)
      12  {
      13    struct S s;
      14    __builtin_memcpy (s.arr, A, 4);
      15    foo (s);
      16    return 0;
      17  }