diff --git a/src/depot_gui.cpp b/src/depot_gui.cpp
--- a/src/depot_gui.cpp
+++ b/src/depot_gui.cpp
@@ -95,28 +95,28 @@ static const WindowDesc _train_depot_des
 	WDP_AUTO, WDP_AUTO, 36, 27, 362, 123,
 	WC_VEHICLE_DEPOT, WC_NONE,
 	WDF_STD_TOOLTIPS | WDF_STD_BTN | WDF_DEF_WIDGET | WDF_UNCLICK_BUTTONS | WDF_STICKY_BUTTON | WDF_RESIZABLE,
-	NULL, _nested_train_depot_widgets, lengthof(_nested_train_depot_widgets)
+	_nested_train_depot_widgets, lengthof(_nested_train_depot_widgets)
 );
 
 static const WindowDesc _road_depot_desc(
 	WDP_AUTO, WDP_AUTO, 36, 27, 316, 97,
 	WC_VEHICLE_DEPOT, WC_NONE,
 	WDF_STD_TOOLTIPS | WDF_STD_BTN | WDF_DEF_WIDGET | WDF_UNCLICK_BUTTONS | WDF_STICKY_BUTTON | WDF_RESIZABLE,
-	NULL, _nested_train_depot_widgets, lengthof(_nested_train_depot_widgets)
+	_nested_train_depot_widgets, lengthof(_nested_train_depot_widgets)
 );
 
 static const WindowDesc _ship_depot_desc(
 	WDP_AUTO, WDP_AUTO, 36, 27, 306, 99,
 	WC_VEHICLE_DEPOT, WC_NONE,
 	WDF_STD_TOOLTIPS | WDF_STD_BTN | WDF_DEF_WIDGET | WDF_UNCLICK_BUTTONS | WDF_STICKY_BUTTON | WDF_RESIZABLE,
-	NULL, _nested_train_depot_widgets, lengthof(_nested_train_depot_widgets)
+	_nested_train_depot_widgets, lengthof(_nested_train_depot_widgets)
 );
 
 static const WindowDesc _aircraft_depot_desc(
 	WDP_AUTO, WDP_AUTO, 36, 27, 332, 99,
 	WC_VEHICLE_DEPOT, WC_NONE,
 	WDF_STD_TOOLTIPS | WDF_STD_BTN | WDF_DEF_WIDGET | WDF_UNCLICK_BUTTONS | WDF_STICKY_BUTTON | WDF_RESIZABLE,
-	NULL, _nested_train_depot_widgets, lengthof(_nested_train_depot_widgets)
+	_nested_train_depot_widgets, lengthof(_nested_train_depot_widgets)
 );
 
 extern void DepotSortList(VehicleList *list);