diff --git a/src/airport_gui.cpp b/src/airport_gui.cpp
--- a/src/airport_gui.cpp
+++ b/src/airport_gui.cpp
@@ -136,7 +136,7 @@ void ShowBuildAirToolbar()
 	if (!IsValidPlayer(_current_player)) return;
 
 	DeleteWindowByClass(WC_BUILD_TOOLBAR);
-	Window *w = AllocateWindowDescFront(&_air_toolbar_desc, TRANSPORT_AIR);
+	Window *w = AllocateWindowDescFront<Window>(&_air_toolbar_desc, TRANSPORT_AIR);
 	if (_patches.link_terraform_toolbar) ShowTerraformToolbar(w);
 }