1 error: this pattern takes a reference on something that is being de-referenced
2 --> $DIR/needless_borrowed_ref.rs:7:34
4 LL | let _ = v.iter_mut().filter(|&ref a| a.is_empty());
5 | ^^^^^^ help: try removing the `&ref` part and just keep: `a`
7 = note: `-D clippy::needless-borrowed-reference` implied by `-D warnings`
9 error: aborting due to previous error