anchor.diff:    (1 . 2))
   
   (defcstruct (struct-pair+1 :class pair+1)
  -  (p struct-pair)
  +  (p (:pointer (:struct struct-pair)))
     (c :int))
   
   (defmethod translate-from-foreign (pointer (type pair+1))
  
positive.code:   (1 . 2))
  
  (defcfun "pair_pointer_sum" :int
    (p struct-pair))   ; XXX: to be changed to (:pointer (:struct pair))
  
  (deftest struct-values.translation.2
      (pair-pointer-sum '(1 . 2))
  
negative.code:   (p (:struct pair+1)))
  
  (defcfun "pair_plus_one_pointer_sum" :int
    (p (:pointer (:struct struct-pair+1))))
  
  (deftest struct-values.translation.ppo.2
      (pair-plus-one-pointer-sum '((1 . 2) . 3))
  