gcc/testsuite/gcc.c-torture/compile/trunc.c

/* { dg-additional-options "-std=gnu89" } */

main ()
{
  printf ("%x, %x\n", (unsigned char) main, main);
}

foo (p)
     char *p;
{
  p[0] = (char)foo;
  p[1] = (char)foo;
}