--- a/src/misc_gui.cpp	Thu May 08 14:04:52 2008 +0000
+++ b/src/misc_gui.cpp	Thu May 08 14:14:16 2008 +0000
@@ -97,8 +97,7 @@
 {
 	DeleteWindowById(WC_LAND_INFO, 0);
 
-	Window *w = new Window(&_land_info_desc);
-	WP(w, void_d).data = &_landinfo_data;
+	new Window(&_land_info_desc);
 
 	Player *p = GetPlayer(IsValidPlayer(_local_player) ? _local_player : PLAYER_FIRST);
 	Town *t = ClosestTownFromTile(tile, _patches.dist_local_authority);
@@ -202,6 +201,12 @@
 	}
 }
 
+struct scroller_d {
+	int height;
+	uint16 counter;
+};
+assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(scroller_d));
+
 static const char *credits[] = {
 	/*************************************************************************
 	 *                      maximum length of string which fits in window   -^*/
@@ -519,6 +524,13 @@
 	if (te_id != INVALID_TE_ID) RemoveTextEffect(te_id);
 }
 
+struct tooltips_d {
+	StringID string_id;
+	byte paramcount;
+	uint64 params[5];
+};
+assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(tooltips_d));
+
 static const Widget _tooltips_widgets[] = {
 {      WWT_PANEL,   RESIZE_NONE,    14,     0,   199,     0,    31, 0x0, STR_NULL},
 {   WIDGETS_END},