diff -r eec5a7dcbf61 -r fcf5fb2548eb src/autoreplace_gui.cpp
--- a/src/autoreplace_gui.cpp	Mon Apr 14 20:32:36 2008 +0000
+++ b/src/autoreplace_gui.cpp	Tue Apr 15 00:47:19 2008 +0000
@@ -19,10 +19,24 @@
 #include "gfx_func.h"
 #include "player_func.h"
 #include "widgets/dropdown_func.h"
+#include "engine_func.h"
 
 #include "table/sprites.h"
 #include "table/strings.h"
 
+struct replaceveh_d {
+	byte sel_index[2];
+	EngineID sel_engine[2];
+	uint16 count[2];
+	bool wagon_btnstate; ///< true means engine is selected
+	EngineList list[2];
+	bool update_left;
+	bool update_right;
+	bool init_lists;
+	GroupID sel_group;
+};
+assert_compile(WINDOW_CUSTOM_SIZE >= sizeof(replaceveh_d));
+
 static RailType _railtype_selected_in_replace_gui;
 
 static bool _rebuild_left_list;