Film with most incredible cast?

What film features the most incredible list of actors?
Not necessarily the best casting ever, but as in it's incredible to have all these people in one movie. (Excluding cameos and such minimal parts.)


Take Alien for example: Sigourney Weaver, Ian Holm, John Hurt, Harry Dean Stanton, Yaphet Kotto, Tom Skerrit, Harry Dean Stanton
Or Escape from New York: Kurt Russell, Lee van Cleef, Ernest Borgnine, Donald Pleasence, Isaac Hayes... and again, Harry Dean Stanton

If dead actors count, it’s 1963’s How the West Was Won, which had a cast including Jimmy Stewart, Gregory Peck, John Wayne, Spencer Tracy, Henry Fonda, Walter Brennan, Richard Widmark, Debbie Reynolds, Caroll Baker, Lee Cobb, Thelma Ritter, Robert Preston, Carolyn Jones, George Peppard, Eli Wallach, Raymond Massey, Andy Devine, David Brian, Russ Tamblyn, Henry Morgan, Agnes Moorhead, Mickey Shaugnessy, Karl Malden, and Brigid Bazlen.

A few on my list:
One Flew Over the Cuckoo's Nest
Trading Places
Dr. Strangelove (with Peter Sellers covering three roles)