anchor.diff:  	  (gethash instruction *instruction-table*)))
   
   (defmethod draw-instruction ((instruction funcall-instruction) stream)
  -  (draw-location (fun instruction) stream)
  +  (draw-location-info (fun instruction) stream)
     (format stream "   ~a [label = \"funcall\"];~%"
   	  (gethash instruction *instruction-table*))
     (format stream "   ~a -> ~a [color = red, style = dashed];~%"
  
positive.code: ;;; Compile an abstract syntax tree.
  
  (defun new-temporary ()
    (make-instance 'sicl-env:lexical-location))
  
  (defun nil-fill (value-context successor)
    (let ((next successor))
  
negative.code: 
  (defmethod compile-ast ((ast p1:constant-ast) value-context successor)
    (cond ((null value-context)
  	 (error "Constant found in a context where no value required")
  	 successor)
  	((eq value-context t)
  	 (let ((temp (new-temporary)))
  