When Bob met Al...

"Return of the Jedi"

The cast: Pacino as Chewbacca; De Niro as Han Solo

Script excerpt:
[Han and Chewbacca are reunited]
Han Solo: Ch-Chewie! I can't see, pal. What's going on?
[Chewie: Hoo-ah!]
Han Solo: Luke? Luke's crazy! He can't even take care of himself, much less rescue anybody.
[Chewie barks again, Hoo-ah, Hoo-ah!]
Han Solo: A Jedi Knight? Jeez, I'm out of it for a little while, everyone gets delusions of grandeur!