It's funny reading the cockpit lav comments here only because Philippine Airlines had 1 747 with a cockpit lav and I remember when it retired, the Philippines aviation pages were full of 747 pilots going, "No!! Now I always have to do the walk of shame". For a pilot group that doesn't seem very rabble rabble, a future without cockpit pooping really brought out the rabble rabble. Haha.
I suppose the 747-400 cockpit is larger, but I'd imagine you still smell it. Especially on MNL-LAX/SFO where 2+ meals pass thru each pilot haha. And Filipinos love their garlic.