diff -r 1d79b44ccbc9 -r f1fec6d1559a window.c
--- a/window.c	Tue Nov 15 08:49:46 2005 +0000
+++ b/window.c	Tue Nov 15 09:00:02 2005 +0000
@@ -1548,7 +1548,7 @@
 
 void InvalidateWindow(byte cls, WindowNumber number)
 {
-	Window *w;
+	const Window* w;
 
 	for (w = _windows; w != _last_window; w++) {
 		if (w->window_class == cls && w->window_number == number) SetWindowDirty(w);