diff --git a/src/depot_gui.cpp b/src/depot_gui.cpp
index 26cd8ef1ca..3101b01885 100644
--- a/src/depot_gui.cpp
+++ b/src/depot_gui.cpp
@@ -100,6 +100,20 @@ static const Widget _depot_widgets[] = {
 	{   WIDGETS_END},
 };
 
+
+struct depot_d {
+	VehicleID sel;
+	VehicleType type;
+	bool generate_list;
+	uint16 engine_list_length;
+	uint16 wagon_list_length;
+	uint16 engine_count;
+	uint16 wagon_count;
+	Vehicle **vehicle_list;
+	Vehicle **wagon_list;
+};
+assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(depot_d));
+
 static void DepotWndProc(Window *w, WindowEvent *e);
 
 static const WindowDesc _train_depot_desc = {
diff --git a/src/window_gui.h b/src/window_gui.h
index 73f7065e70..2edef2343a 100644
--- a/src/window_gui.h
+++ b/src/window_gui.h
@@ -538,19 +538,6 @@ struct def_d {
 };
 assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(def_d));
 
-struct depot_d {
-	VehicleID sel;
-	VehicleType type;
-	bool generate_list;
-	uint16 engine_list_length;
-	uint16 wagon_list_length;
-	uint16 engine_count;
-	uint16 wagon_count;
-	Vehicle **vehicle_list;
-	Vehicle **wagon_list;
-};
-assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(depot_d));
-
 enum SortListFlags {
 	VL_NONE    = 0,      ///< no sort
 	VL_DESC    = 1 << 0, ///< sort descending or ascending