1 files changed, 1 insertions, 0 deletions

diff --git a/src/lisp.h b/src/lisp.h
index 754356689d9..8081e7c4fe4 100644
--- a/src/lisp.h
+++ b/src/lisp.h
@@ -3058,6 +3058,7 @@ extern void record_change P_ ((int, int));
 extern void record_property_change P_ ((int, int, Lisp_Object, Lisp_Object,
                                         Lisp_Object));
 extern void syms_of_undo P_ ((void));
+extern Lisp_Object Vundo_outer_limit;
 
 /* defined in textprop.c */
 extern Lisp_Object Qfont, Qmouse_face;