diff --git a/lisp/uncompress.el b/lisp/uncompress.el
index c731c23baf6..53439190a1d 100644
--- a/lisp/uncompress.el
+++ b/lisp/uncompress.el
@@ -75,9 +75,9 @@ It then selects a major mode from the uncompressed file name and contents."
   (let ((buffer-read-only nil)
 	(coding-system-for-write 'no-conversion)
 	(coding-system-for-read
-	 (find-operation-coding-system
-	  'insert-file-contents
-	  buffer-file-name t)))
+	 (car (find-operation-coding-system
+	       'insert-file-contents
+	       buffer-file-name t))))
     (shell-command-on-region (point-min) (point-max) uncompress-program t))
   (goto-char (point-min))
   (message "Uncompressing...done")