error[E0277]: the trait bound `Struct: Eq` is not satisfied --> $DIR/where-clauses-unsatisfied.rs:6:10 | LL | drop(equal(&Struct, &Struct)) | ^^^^^ the trait `Eq` is not implemented for `Struct` | note: required by a bound in `equal` --> $DIR/where-clauses-unsatisfied.rs:1:45 | LL | fn equal(a: &T, b: &T) -> bool where T : Eq { a == b } | ^^ required by this bound in `equal` help: consider annotating `Struct` with `#[derive(Eq)]` | LL | #[derive(Eq)] | error: aborting due to previous error For more information about this error, try `rustc --explain E0277`.