(define-method-combination test-method-combination ()
((around (:around))
(primary () :required t))
`(call-method ,(first around) ( (make-method (call-method ,(first primary))) )))
(defgeneric foo (x)
(:method-combination test-method-combination))
(defmethod foo((o integer))
nil)
(defmethod foo :around ((o integer))
(call-next-method o))
(foo 23)
causes an error: value NIL is not of the expected type SIMPLE-VECTOR.
The bug seems to have been there forever, but the recently released ASDF 1.128 and later actually uses non-standard method combinations and evokes this bug in normal use.
