warning: the feature `type_alias_impl_trait` is incomplete and may not be safe to use and/or cause compiler crashes --> $DIR/no_revealing_outside_defining_module.rs:3:32 | LL | #![cfg_attr(full_tait, feature(type_alias_impl_trait))] | ^^^^^^^^^^^^^^^^^^^^^ | = note: `#[warn(incomplete_features)]` on by default = note: see issue #63063 for more information error[E0308]: mismatched types --> $DIR/no_revealing_outside_defining_module.rs:18:19 | LL | pub type Boo = impl ::std::fmt::Debug; | ---------------------- the found opaque type ... LL | let _: &str = bomp(); | ---- ^^^^^^ expected `&str`, found opaque type | | | expected due to this | = note: expected reference `&str` found opaque type `impl Debug` error[E0308]: mismatched types --> $DIR/no_revealing_outside_defining_module.rs:22:5 | LL | pub type Boo = impl ::std::fmt::Debug; | ---------------------- the expected opaque type ... LL | fn bomp() -> boo::Boo { | -------- expected `impl Debug` because of return type LL | "" | ^^ expected opaque type, found `&str` | = note: expected opaque type `impl Debug` found reference `&'static str` error: aborting due to 2 previous errors; 1 warning emitted For more information about this error, try `rustc --explain E0308`.