diff --git a/pcl/boot.lisp b/pcl/boot.lisp
index eb38a60a841c8495804eef4c5e4e9a964c86484b..9d690d35d74b60da00599da76135e71b70322320 100644
--- a/pcl/boot.lisp
+++ b/pcl/boot.lisp
@@ -1362,6 +1362,7 @@ work during bootstrapping.
 (defmacro with-slots (slots instance &body body)
   (let ((in (gensym)))
     `(let ((,in ,instance))
+       #+cmu (declare (ext:ignorable ,in))
        ,@(and (symbolp instance)
 	      `((declare (variable-rebinding ,in ,instance))
        (symbol-macrolet ,(mapcar #'(lambda (slot-entry)
@@ -1381,6 +1382,7 @@ work during bootstrapping.
 (defmacro with-accessors (slots instance &body body)
   (let ((in (gensym)))
     `(let ((,in ,instance))
+       #+cmu (declare (ext:ignorable ,in))
        ,@(and (symbolp instance)
 	      `((declare (variable-rebinding ,in ,instance))
        (symbol-macrolet ,(mapcar #'(lambda (slot-entry)