warning: the feature `return_position_impl_trait_in_trait` is incomplete and may not be safe to use and/or cause compiler crashes --> $DIR/dont-project-to-rpitit-with-no-value.rs:4:12 | LL | #![feature(return_position_impl_trait_in_trait)] | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | = note: see issue #91611 for more information = note: `#[warn(incomplete_features)]` on by default error[E0046]: not all trait items implemented, missing: `foo` --> $DIR/dont-project-to-rpitit-with-no-value.rs:12:1 | LL | fn foo(&self) -> impl Sized; | ---------------------------- `foo` from trait ... LL | impl MyTrait for i32 { | ^^^^^^^^^^^^^^^^^^^^ missing `foo` in implementation error: aborting due to previous error; 1 warning emitted For more information about this error, try `rustc --explain E0046`.