Jump to label inside a switch statement in C

switch-labels-goto.c

/*
 * Silly example demonstrating that it is valid to jump
 * to arbitrary labels inside "switch" statements using
 * "goto" in C.
 */

bool is_not_small_power_of_two (int value)
{
  if (value < 0) {
    /* It is legal to jump into a switch */
    goto do_return_false;
  }

  switch (value) {
    case 2:
    case 4:
    case 8:
    case 16:
    case 32:
    case 64:
    case 128:
    default:
    do_return_false: /* Label inside "switch" */
      return false;
  }
  
  return true;
}

int
main (int arcg, char *argv[])
{
  if (argc != 2) {
    fprintf (stderr, "Usage: %s number\n", argv[0]);
    return 111;
  }
  return is_not_small_power_of_two (atoi (argv[1]))
    ? EXIT_SUCCESS
    : EXIT_FAILURE;
}