Can't define TAIT with region params inside of a closure

[compiler-errors]

I tried this code:

#![feature(type_alias_impl_trait)]

type Tait<'a> = impl Sized;

fn foo<'a>() where Tait<'a>: {
    let _ = |x: &'a ()| {
        let _: Tait<'a> = x;
    };
}

I expected to see it work

Instead, this happened:

error[E0700]: hidden type for `Tait<'a>` captures lifetime that does not appear in bounds
 --> src/lib.rs:7:16
  |
3 | type Tait<'a> = impl Sized;
  |                 ---------- opaque type defined here
4 |
5 | fn foo<'a>() where Tait<'a>: {
  |        -- hidden type `&'a ()` captures the lifetime `'a` as defined here
6 |     let _ = |x: &'a ()| {
7 |         let _: Tait<'a> = x;
  |                ^^^^^^^^

This probably has to do something with promoting member constraints from a closure or something? idk.

[aliemjay]

This is #105498. Close as duplicate?

[compiler-errors]

yup will close