gc_enable(mrb_state *mrb, mrb_value obj)
{
  mrb_bool old = mrb->gc.disabled;

  mrb->gc.disabled = FALSE;

  return mrb_bool_value(old);
}
gc_enable(mrb_state *mrb, mrb_value obj)
{
  mrb_bool old = mrb->gc.disabled;

  mrb->gc.disabled = FALSE;

  return mrb_bool_value(old);
}