diff --git a/lisp/ob-comint.el b/lisp/ob-comint.el
index c6a00395f..123e42a2b 100644
--- a/lisp/ob-comint.el
+++ b/lisp/ob-comint.el
@@ -151,8 +151,10 @@ FILE exists at end of evaluation."
    (if (= (aref string (1- (length string))) ?\n) string (concat string "\n")))
   ;; From Tramp 2.1.19 the following cache flush is not necessary
   (if (file-remote-p default-directory)
-      (with-parsed-tramp-file-name default-directory nil
-	(tramp-flush-directory-property v "")))
+      (let (v)
+	(ignore v)
+	(with-parsed-tramp-file-name default-directory nil
+	  (tramp-flush-directory-property v ""))))
   (while (not (file-exists-p file)) (sit-for (or period 0.25))))
 
 (provide 'ob-comint)