Won Ton Ton: The Dog Who Saved Hollywood (1976)

WON TON TON: THE DOG WHO SAVED HOLLYWOOD  (1976)  ¢ ¢ 1/2
    D: Michael Winner
    Bruce Dern, Madeline Kahn, Art Carney,
    Teri Garr, Ron Liebman, Phil Silvers
In 1923, the world's smartest German shepherd becomes Hollywood's biggest star, which works out well for an aspiring filmmaker (Bruce Dern) and a would-be actress (Madeline Kahn), after they save the dog from the gallows. Something like "It's a Mad Mad Mad Mad World", it's a comedy in which the funny stuff is kind of secondary  to the cameos. Everybody from Rory Calhoun, Virginia Mayo and Andy Devine to Johnny Weissmuller, Victor Mature and the Ritz Brothers turns up in it, some for no more than a couple of seconds, and that's pretty much the point of the film. You'll have to look fast for your favorites.