diff --git a/pathfind.c b/pathfind.c
--- a/pathfind.c
+++ b/pathfind.c
@@ -1,5 +1,6 @@
 #include "stdafx.h"
 #include "openttd.h"
+#include "functions.h"
 #include "map.h"
 #include "tile.h"
 #include "pathfind.h"