// Checks that regions which appear in a trait object type are // observed by the variance inference algorithm (and hence // `TOption` is contavariant w/r/t `'a` and not bivariant). // // Issue #18262. #![feature(rustc_attrs)] use std::mem; trait T { fn foo(&self); } #[rustc_variance] struct TOption<'a> { //~ ERROR ['a: +] v: Option>, } fn main() { }