diff --git a/src/date_gui.cpp b/src/date_gui.cpp
--- a/src/date_gui.cpp
+++ b/src/date_gui.cpp
@@ -151,7 +151,7 @@ struct SetDateWindow : Window {
 		this->DrawWidgets();
 	}
 
-	virtual void OnClick(Point pt, int widget)
+	virtual void OnClick(Point pt, int widget, int click_count)
 	{
 		switch (widget) {
 			case SDW_DAY: