diff --git a/src/move.c b/src/move.c
index b061a75..5bf2592 100644
--- a/src/move.c
+++ b/src/move.c
@@ -594,6 +594,22 @@
 }
 
 /*
+ * Display of line has changed for "buf", invalidate cursor position and
+ * w_botline.
+ */
+    void
+changed_line_display_buf(buf_T *buf)
+{
+    win_T *wp;
+
+    FOR_ALL_WINDOWS(wp)
+	if (wp->w_buffer == buf)
+	    wp->w_valid &= ~(VALID_WROW|VALID_WCOL|VALID_VIRTCOL
+				|VALID_CROW|VALID_CHEIGHT
+				|VALID_TOPLINE|VALID_BOTLINE|VALID_BOTLINE_AP);
+}
+
+/*
  * Make sure the value of curwin->w_botline is valid.
  */
     void