+\f
+;;; Redefinition of classes should alter the type hierarchy (BUG 140):
+(defclass superclass () ())
+(defclass maybe-subclass (superclass) ())
+(assert-t-t (subtypep 'maybe-subclass 'superclass))
+(defclass maybe-subclass () ())
+(assert-nil-t (subtypep 'maybe-subclass 'superclass))
+\f