diff --git a/src/newgrf_airporttiles.cpp b/src/newgrf_airporttiles.cpp
--- a/src/newgrf_airporttiles.cpp
+++ b/src/newgrf_airporttiles.cpp
@@ -221,7 +221,7 @@ static uint32 AirportTileGetRandomBits(c
 	return (st == NULL ? 0 : st->random_bits) | (tile == INVALID_TILE ? 0 : GetStationTileRandomBits(tile) << 16);
 }
 
-static void AirportTileResolver(ResolverObject *res, const AirportTileSpec *ats, TileIndex tile, const Station *st)
+static void AirportTileResolver(ResolverObject *res, const AirportTileSpec *ats, TileIndex tile, Station *st)
 {
 	res->GetRandomBits = AirportTileGetRandomBits;
 	res->GetTriggers   = NULL;
diff --git a/src/newgrf_spritegroup.h b/src/newgrf_spritegroup.h
--- a/src/newgrf_spritegroup.h
+++ b/src/newgrf_spritegroup.h
@@ -365,7 +365,7 @@ struct ResolverObject {
 			TileContext context;           ///< Are we resolving sprites for the upper halftile, or on a bridge?
 		} routes;
 		struct {
-			const struct Station *st;      ///< Station of the airport for which the callback is run, or NULL for build gui.
+			struct Station *st;            ///< Station of the airport for which the callback is run, or NULL for build gui.
 			byte airport_id;               ///< Type of airport for which the callback is run
 			byte layout;                   ///< Layout of the airport to build.
 			TileIndex tile;                ///< Tile for the callback, only valid for airporttile callbacks.
diff --git a/src/newgrf_station.h b/src/newgrf_station.h
--- a/src/newgrf_station.h
+++ b/src/newgrf_station.h
@@ -112,7 +112,7 @@ const StationSpec *GetStationSpec(TileIn
 uint32 GetPlatformInfo(Axis axis, byte tile, int platforms, int length, int x, int y, bool centred);
 
 SpriteID GetCustomStationRelocation(const StationSpec *statspec, BaseStation *st, TileIndex tile, uint32 var10 = 0);
-SpriteID GetCustomStationFoundationRelocation(const StationSpec *statspec, const BaseStation *st, TileIndex tile, uint layout, uint edge_info);
+SpriteID GetCustomStationFoundationRelocation(const StationSpec *statspec, BaseStation *st, TileIndex tile, uint layout, uint edge_info);
 uint16 GetStationCallback(CallbackID callback, uint32 param1, uint32 param2, const StationSpec *statspec, BaseStation *st, TileIndex tile);
 
 /* Allocate a StationSpec to a Station. This is called once per build operation. */