It's a Mad, Mad, Mad, Mad World (1963)

Comedy sludge. You can't expect a movie to be funny just because you've jammed a bunch of comedians into it. Leaden timing, pointless manic yelling and mugging, endless car chases and destruction, and a complete lack of wit make for a sadly unfunny comedy. The one time I laughed was at Jerry Lewis' brief cameo (because of real-life idiots who do the kind of thing he does in the movie), so that says something.