diff --git a/src/map_func.h b/src/map_func.h
--- a/src/map_func.h
+++ b/src/map_func.h
@@ -241,11 +241,11 @@ static inline TileIndexDiff ToTileIndexD
 	 * @param y Another tile to add
 	 * @return The resulting tile(index)
 	 */
-	#define TILE_ADD(x, y) ((x) + (y))
+#	define TILE_ADD(x, y) ((x) + (y))
 #else
 	extern TileIndex TileAdd(TileIndex tile, TileIndexDiff add,
 		const char *exp, const char *file, int line);
-	#define TILE_ADD(x, y) (TileAdd((x), (y), #x " + " #y, __FILE__, __LINE__))
+#	define TILE_ADD(x, y) (TileAdd((x), (y), #x " + " #y, __FILE__, __LINE__))
 #endif
 
 /**