Incorrect report of invalid # of arguments

[Paul F. Dietz]

(defun bug068 (b)
   (tagbody
     (labels ((%f13 (&optional (f13-1 0) &key &allow-other-keys)
                b))
       (if nil
           (%f13 (go tag8))
           (%f13))
       b)
    tag8))

(bug068 0) ==> invalid number of arguments: 1