| error[E0658]: cannot cast `dyn A` to `dyn B`, trait upcasting coercion is experimental |
| --> $DIR/upcast-through-struct-tail.rs:11:5 |
| | |
| LL | x |
| | ^ |
| | |
| = note: see issue #65991 <https://github.com/rust-lang/rust/issues/65991> for more information |
| = help: add `#![feature(trait_upcasting)]` to the crate attributes to enable |
| = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date |
| = note: required when coercing `Box<Wrapper<(dyn A + 'a)>>` into `Box<Wrapper<(dyn B + 'a)>>` |
| |
| error: aborting due to 1 previous error |
| |
| For more information about this error, try `rustc --explain E0658`. |