anchor.diff:  (defun compute-all-lookaheads (kernels grammar)
     "Compute the LR(1) lookaheads for all the collections in KERNELS."
     (declare (list kernels) (type grammar grammar))
  -  (setf (item-lookaheads (kernel-item (car kernels))) (list 'eof))
  +  (setf (item-lookaheads (kernel-item (car kernels))) (list 'yacc-eof-symbol))
     (let ((previously-changed kernels) (changed '())
           (propagate-only nil))
       (declare (optimize (speed 3) (space 0)))
  
positive.code:                  (cond
                     ((and (eq 's-prime (item-symbol item))
                           (= 1 (item-position item)))
                      (when (member 'eof la)
                        (set-action k (list 'eof)
                                    (make-accept-action)
                                    (item-production item))))
                     (t
  
negative.code:       (let ((stack (list 0)) symbol value)
          (flet ((next-symbol ()
                   (multiple-value-bind (s v) (funcall lexer)
                     (setq symbol (or s 'yacc-eof-symbol) value v))))
            (next-symbol)
            (loop
             (let* ((state (car stack))
  