diff --git a/waypoint.h b/waypoint.h
--- a/waypoint.h
+++ b/waypoint.h
@@ -59,7 +59,7 @@ int32 RemoveTrainWaypoint(TileIndex tile
 Station *ComposeWaypointStation(TileIndex tile);
 Waypoint *GetWaypointByTile(TileIndex tile);
 void ShowRenameWaypointWindow(const Waypoint *cp);
-void DrawWaypointSprite(int x, int y, int image, int railtype);
+void DrawWaypointSprite(int x, int y, int image, uint railtype);
 void UpdateWaypointSign(Waypoint *cp);
 void FixOldWaypoints(void);
 void UpdateAllWaypointSigns(void);