diff --git a/lisp/progmodes/flymake.el b/lisp/progmodes/flymake.el
index 883f96747b9..ea63420dfae 100644
--- a/lisp/progmodes/flymake.el
+++ b/lisp/progmodes/flymake.el
@@ -343,7 +343,8 @@ region is invalid."
                 (let* ((beg (fallback-bol))
                        (end (fallback-eol beg)))
                   (cons beg end)))))))
-    (error (flymake-log :warning "Invalid region line=%s col=%s" line col))))
+    (error (flymake-log :warning "Invalid region line=%s col=%s")
+           nil)))
 
 (defvar flymake-diagnostic-functions nil
   "Special hook of Flymake backends that check a buffer.