Eastwood rarely worked with name directors, but they might have gotten along. From the Wikipedia entry on Torn Curtain
The working relationship between Hitchcock and Newman was problematic. Newman came from a different generation of actors from the likes of Cary Grant and James Stewart. He questioned Hitchcock about the script and the characterization throughout filming. Hitchcock later said he found Newman's manner and approach unacceptable and disrespectful. Newman insisted that he meant no disrespect toward Hitchcock, and once said, "I think Hitch and I could have really hit it off, but the script kept getting in the way." When Newman, a Method actor, consulted Hitchcock about his character's motivations, the director replied: "motivation is your salary."
I can see Hitchcock having an easier time working with Eastwood.