diff --git a/src/signs_gui.cpp b/src/signs_gui.cpp
--- a/src/signs_gui.cpp
+++ b/src/signs_gui.cpp
@@ -136,7 +136,7 @@ struct SignListWindow : Window, SignList
 		}
 	}
 
-	virtual void OnResize(Point new_size, Point delta)
+	virtual void OnResize(Point delta)
 	{
 		this->vscroll.cap += delta.y / 10;
 	}