struct VEC_char_base
{
  unsigned num;
  unsigned alloc;
  short vec[1];
};

short __attribute__((noinline))
foo (struct VEC_char_base *p, int i)
{
  short *q;
  p->vec[i] = 0;
  q = &p->vec[8];
  *q = 1;
  return p->vec[i];
}

extern void abort (void);
extern void *malloc (__SIZE_TYPE__);

int
main()
{
  struct VEC_char_base *p = malloc (sizeof (struct VEC_char_base) + 256);
  if (foo (p, 8) != 1)
    abort ();
  return 0;
}