anchor.diff:                                   (slot-def (accessor-method-slot-definition (first applicable-methods)))
                                    (slot-name (slot-definition-name slot-def))
                                    (effective-slot (find-effective-slot instance slot-name)))
  +                            (register-redefinition-flusher gf class)
                               (cond (effective-slot
                                      (let ((location (safe-slot-definition-location effective-slot)))
                                        (lambda (object)
  
positive.code:                                  (slot-def (accessor-method-slot-definition (first applicable-methods)))
                                   (slot-name (slot-definition-name slot-def))
                                   (effective-slot (find-effective-slot instance slot-name)))
                              (cond (effective-slot
                                     (let* ((location (safe-slot-definition-location effective-slot))
                                            (typecheck (safe-slot-definition-typecheck effective-slot))
  
negative.code:                                                    repeat n-required
                                                     collect (eql-specializer-object spec)))))))
  
  (sys.int::defglobal *redefinition-flush-table* (make-hash-table))
  (sys.int::defglobal *redefinition-flush-table-lock*
      (mezzano.supervisor:make-mutex '*redefinition-flush-table*))
  
  (defun register-redefinition-flusher (gf class)
    "Cause GF's EMF table to be flushed when CLASS is redefined."
    (mezzano.supervisor:with-mutex (*redefinition-flush-table-lock*)
      (pushnew gf (gethash class *redefinition-flush-table* '()))))
  
  (defun flush-emf-tables-on-class-redefinition (class)
    ;; CLASS is being redefined, flush any associated the EMF tables and wipe away the entry.
    (let ((gfs (mezzano.supervisor:with-mutex (*redefinition-flush-table-lock*)
                 (prog1
                     (gethash class *redefinition-flush-table*)
                   (remhash class *redefinition-flush-table*)))))
      (dolist (gf gfs)
        (reset-gf-emf-table gf))))
  
  (defun slow-single-dispatch-method-lookup* (gf argument-offset args state)
    (declare (notinline slot-value (setf slot-value))) ; Bootstrap hack
    (let ((emf-table (classes-to-emf-table gf)))
  