error: lifetime may not live long enough --> $DIR/issue-95272.rs:10:13 | LL | fn test<'a, 'b>(x: Cell<&'a ()>, y: Cell<&'b ()>) { | -- -- lifetime `'b` defined here | | | lifetime `'a` defined here LL | let f = check; | ^^^^^ assignment requires that `'a` must outlive `'b` | = help: consider adding the following bound: `'a: 'b` = note: requirement occurs because of a function pointer to `check` = note: the function `check` is invariant over the parameter `'a` = help: see for more information about variance error: aborting due to 1 previous error