anchor.diff:  (defun wrong-argument-count-p (warning)
     "True if WARNING is about a function call with a wrong number of arguments."
     #+sbcl (when (typep warning '(and warning simple-condition))
  -           (let ((control (simple-condition-format-control warning)))
  +           (let ((control (format-control-string-or-nil warning)))
                (and (search "The function ~S is called" control)
                     (search "but wants exactly" control)))))
   
  
positive.code:   #-sbcl nil
    #+sbcl
    (when (typep warning '(and warning simple-condition))
      (let ((control (simple-condition-format-control warning)))
        (search "compiled before a compiler-macro was defined for it" control))))
  
  (deftype compiler-macro-after-function-use ()
  
negative.code:   "True when WARNING is a warning about changed function FTYPE."
    #+sbcl
    (when (typep warning '(and warning simple-condition))
      (let ((control (format-control-string-or-nil warning))
            (args (simple-condition-format-arguments warning)))
        (and (search "function" control)
             (search "clobbers" control)
  