Error when trying use trait alias for Fn() in impl

[DustinByfuglien]

This code produce compiling error:

#![feature(trait_alias)]

struct MyStruct {}
trait MyFn = Fn(&MyStruct);

fn foo (_: impl MyFn) {}

fn main () {
    foo(|_| {});
}

(Playground)

Errors:

   Compiling playground v0.0.1 (/playground)
error[E0631]: type mismatch in closure arguments
 --> src/main.rs:9:5
  |
9 |     foo(|_| {});
  |     ^^^ --- found signature of `fn(_) -> _`
  |     |
  |     expected signature of `for<'r> fn(&'r MyStruct) -> _`
  |
note: required by `foo`
 --> src/main.rs:6:1
  |
6 | fn foo (_: impl MyFn) {}
  | ^^^^^^^^^^^^^^^^^^^^^

error[E0271]: type mismatch resolving `for<'r> <[closure@src/main.rs:9:9: 9:15] as std::ops::FnOnce<(&'r MyStruct,)>>::Output == ()`
 --> src/main.rs:9:5
  |
9 |     foo(|_| {});
  |     ^^^ expected bound lifetime parameter, found concrete lifetime
  |
note: required by `foo`
 --> src/main.rs:6:1
  |
6 | fn foo (_: impl MyFn) {}
  | ^^^^^^^^^^^^^^^^^^^^^

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0271`.
error: Could not compile `playground`.

To learn more, run the command again with --verbose.

But when non aliased trait used, then no error occured. That is when we replace
fn foo (_: impl MyFn) {}
with
fn foo (_: impl Fn(&MyStruct)) {}

[DustinByfuglien]

May be "F-trait_alias" label needed for this issue.

[kadiwa4]

Fixed on latest nightly 2023-01-15.
@rustbot label: +F-trait_alias +E-needs-test