warning: trait objects without an explicit `dyn` are deprecated --> $DIR/lint-group-allowed-lint-group.rs:10:25 | LL | pub fn function(_x: Box) {} | ^^^^^^^^^ | = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021! = note: for more information, see = note: `--force-warn bare-trait-objects` implied by `--force-warn rust-2018-idioms` help: if this is a dyn-compatible trait, use `dyn` | LL | pub fn function(_x: Box) {} | +++ warning: 1 warning emitted