def _check_diff(changes):
    '''
    Check the diff for signs of incorrect argument handling in previous
    releases, as discovered here:

    https://github.com/saltstack/salt/pull/39996#issuecomment-288025200
    '''
    for conf_dict in changes:
        if conf_dict == 'Networks':
            continue
        for item in changes[conf_dict]:
            if changes[conf_dict][item]['new'] is None:
                old = changes[conf_dict][item]['old']
                if old == '':
                    return True
                else:
                    try:
                        if all(x == '' for x in old):
                            return True
                    except TypeError:
                        # Old value is not an iterable type
                        pass
    return False
Check the diff for signs of incorrect argument handling in previous
    releases, as discovered here:

    https://github.com/saltstack/salt/pull/39996#issuecomment-288025200