use std::cell::Cell; fn check<'a, 'b>(x: Cell<&'a ()>, y: Cell<&'b ()>) where 'a: 'b, { } fn test<'a, 'b>(x: Cell<&'a ()>, y: Cell<&'b ()>) { let f = check; f(x, y); //~^ ERROR lifetime may not live long enough } fn main() {}