error: to use a constant of type `Vec` in a pattern, `Vec` must be annotated with `#[derive(PartialEq, Eq)]` --> $DIR/issue-115599.rs:5:12 | LL | if let CONST_STRING = empty_str {} | ^^^^^^^^^^^^ | = note: the traits must be derived, manual `impl`s are not sufficient = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralEq.html for details error: aborting due to previous error