diff --git a/src/lisp.h b/src/lisp.h
index 49e87ee98d6..005826f62c1 100644
--- a/src/lisp.h
+++ b/src/lisp.h
@@ -1395,6 +1395,7 @@ extern void message1_nolog ();
 extern void message2 ();
 extern void message2_nolog ();
 extern void message_dolog ();
+extern void message_log_maybe_newline ();
 
 /* Defined in alloc.c */
 extern Lisp_Object Vpurify_flag;