error[E0425]: cannot find value `Foo` in this scope
  --> $DIR/layout-error.rs:24:17
   |
LL |         let a = Foo;
   |                 ^^^ not found in this scope

error[E0658]: type alias impl trait is not permitted here
  --> $DIR/layout-error.rs:30:27
   |
LL |     Task::spawn(&POOL, || cb());
   |                           ^
   |
   = note: see issue #63063 <https://github.com/rust-lang/rust/issues/63063> for more information
   = help: add `#![feature(type_alias_impl_trait)]` to the crate attributes to enable

error: aborting due to 2 previous errors

Some errors have detailed explanations: E0425, E0658.
For more information about an error, try `rustc --explain E0425`.