diff --git a/src/toolbar_gui.cpp b/src/toolbar_gui.cpp
--- a/src/toolbar_gui.cpp
+++ b/src/toolbar_gui.cpp
@@ -1117,7 +1117,7 @@ struct MainToolbarWindow : Window {
 		}
 	}
 
-	virtual void OnResize(Point new_size, Point delta)
+	virtual void OnResize(Point delta)
 	{
 		if (this->width <= TBP_NORMAL_MAXBUTTON * TBP_BUTTONWIDTH) {
 			SplitToolbar(this);
@@ -1311,7 +1311,7 @@ public:
 		_place_proc(tile);
 	}
 
-	virtual void OnResize(Point new_size, Point delta)
+	virtual void OnResize(Point delta)
 	{
 		/* There are 16 buttons plus some spacings if the space allows it.
 		 * Furthermore there are two panels of which one is non - essential