--- a/road_cmd.c	Wed Oct 19 08:34:37 2005 +0000
+++ b/road_cmd.c	Wed Oct 19 14:49:46 2005 +0000
@@ -932,7 +932,7 @@
 	}
 }
 
-static uint GetSlopeZ_Road(TileInfo *ti)
+static uint GetSlopeZ_Road(const TileInfo* ti)
 {
 	uint z = ti->z;
 	int th = ti->tileh;