anchor.diff:  			   (let ((temp (new-temporary)))
   			     (setf next 
   				   (sicl-mir:make-return-instruction
  -				    (list temp) next))
  +				    (list temp)))
   			     (let ((false (make-boolean nil temp next))
   				   (true (make-boolean t temp next)))
   			       (funcall constructor temps (list false true)))))
  
positive.code: 		    (let ((temp (new-temporary)))
  		      (setf next 
  			    (sicl-mir:make-return-instruction
  			     (list temp) next))
  		      (funcall constructor temps temp next)))
  		   (t
  		    (setf next (nil-fill (cdr results) next))
  
negative.code:       context
      (ecase (length successors)
        (1 (cond ((eq results t)
  		(sicl-mir:make-return-instruction (list ast)))
  	       ((null results)
  		(warn "variable compiled in a context with no values")
  		(car successors))
  