diff --git a/src/structs.h b/src/structs.h
index 1fd4309..da5ed2e 100644
--- a/src/structs.h
+++ b/src/structs.h
@@ -2895,6 +2895,7 @@
     int		w_maxwidth;	    // "maxwidth" for popup window
     int		w_wantline;	    // "line" for popup window
     int		w_wantcol;	    // "col" for popup window
+    int		w_firstline;	    // "firstline" for popup window
     int		w_popup_padding[4]; // popup padding top/right/bot/left
     int		w_popup_border[4];  // popup border top/right/bot/left
     char_u	*w_border_highlight[4];  // popup border highlight