anchor.diff:    (with-accessors ((results results)
   		   (successors successors))
         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))
  -	       ((eq ast (car results))
  -		(nil-fill (cdr results) (car successors)))
  -	       (t
  -		(sicl-mir:make-assignment-instruction
  -		 ast
  -		 (car results) 
  -		 (nil-fill (cdr results) (car successors))))))
  -      (2 (if (or (null results) (eq ast (car results)))
  -	     (sicl-mir:make-test-instruction ast successors)
  -	     (sicl-mir:make-assignment-instruction
  -	      ast
  -	      (car results)
  -	      (sicl-mir:make-test-instruction ast successors)))))))
  +    (if (eq results t)
  +	(sicl-mir:make-return-instruction (list ast))
  +	(ecase (length successors)
  +	  (1 (if (null results)
  +		 (progn 
  +		   (warn "variable compiled in a context with no values")
  +		   (car successors))
  +		 (sicl-mir:make-assignment-instruction
  +		  ast
  +		  (car results) 
  +		  (nil-fill (cdr results) (car successors)))))
  +	  (2 (if (null results)
  +		 (sicl-mir:make-test-instruction ast successors)
  +		 (sicl-mir:make-assignment-instruction
  +		  ast
  +		  (car results)
  +		  (sicl-mir:make-test-instruction ast successors))))))))
   
   (defun compile-toplevel (ast)
     (let ((*block-info* (make-hash-table :test #'eq))
  
positive.code: 		     :successors successors
  		     :false-required-p false-required-p)))
  
  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  ;;;
  ;;; Compile an abstract syntax tree in a compilation context.
  
negative.code:   (with-accessors ((results results)
  		   (successors successors))
        context
      (let* ((all-args (cons (sicl-ast:callee-ast ast)
  			   (sicl-ast:argument-asts ast)))
  	   (temps (make-temps all-args)))
        (compile-arguments
         all-args
         temps
         (if (eq results t)
  	   (sicl-mir:make-tailcall-instruction temps)
  	   (sicl-mir:make-funcall-instruction
  	    temps
  	    (sicl-mir:make-get-values-instruction
  	     results (car successors))))))))
  
  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  ;;;
  