The two actors will both reprise their roles as Charles Xavier in the time-travelling 20th Century Fox film.
"It'll be cool, but I don't think we get any scenes together, sadly," he told Empire magazine. "I don't think there's any future self talking to past self."
The actor also discussed the privilege of starring in the X-Men franchise.
"Having an X-Men in your back pocket, which hopefully will go for three movies, it makes you go, 'Right, it doesn't matter if I make 14 films that nobody sees... because in two years' time I'll make another X-Men'.
"Meanwhile, Fox are thinking, 'Why isn't this f**ker out there building his profile so he can make us more money on the second X-Men?' But that's their fault for hiring me!"
McAvoy has been connected to the remake of comic book adaptation The Crow.
He will appear alongside Peter Dinklage, Michael Fassbender, Jennifer Lawrence, Hugh Jackman, Ian McKellen, Anna Paquin, Ellen Page and Shawn Ashmore on the Bryan Singer-directed Marvel Comics film.
X-Men: Days of Future Past is scheduled for release on July 18, 2014.