error[E0658]: `?Trait` is not permitted in supertraits --> $DIR/maybe-bounds.rs:1:11 | LL | trait Tr: ?Sized {} | ^^^^^^ | = note: traits are `?Sized` by default = help: add `#![feature(more_maybe_bounds)]` to the crate attributes to enable = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date error[E0658]: `?Trait` is not permitted in trait object types --> $DIR/maybe-bounds.rs:4:20 | LL | type A1 = dyn Tr + (?Sized); | ^^^^^^^^ | = help: add `#![feature(more_maybe_bounds)]` to the crate attributes to enable = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date error[E0658]: `?Trait` is not permitted in trait object types --> $DIR/maybe-bounds.rs:6:28 | LL | type A2 = dyn for<'a> Tr + (?Sized); | ^^^^^^^^ | = help: add `#![feature(more_maybe_bounds)]` to the crate attributes to enable = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date error: aborting due to 3 previous errors For more information about this error, try `rustc --explain E0658`.