gcc/testsuite/gcc.dg/20041104-1.c

/* This testcase exposed the same bug as PR 15342.  */
/* { dg-options "-O2 -frename-registers -fno-schedule-insns" } */

void *memcpy (void *, const void *, __SIZE_TYPE__);

void f (int n, int (*x)[4])
{
  while (n--)
    {
      int f = x[0][0];
      if (f <= 0)
	memcpy (&x[1], &x[0], sizeof (x[0]));
      else
	memcpy (&x[f], &x[0], sizeof (x[0]));
      f = x[0][2];
      x[0][1] = f;
    }
}