a typo in ira-emit.c?

[Amker.Cheng]

Hi :
I am studying ira right now, there is following code in change_loop

          if (parent_allocno == NULL
              || REGNO (ALLOCNO_REG (parent_allocno)) == REGNO (original_reg))
            {
              if (internal_flag_ira_verbose > 3 && ira_dump_file)
                fprintf (ira_dump_file, "  %i vs parent %i:",
                         ALLOCNO_HARD_REGNO (allocno),
                         ALLOCNO_HARD_REGNO (parent_allocno));
              set_allocno_reg (allocno, create_new_reg (original_reg));
            }
Is it possible that parent_allocno == NULL here? or the fprintf might broken.

Thanks.

-- 
Best Regards.