async_fn_in_trait: lifetime of implemented async trait fn wrongly evaluates to static

[ufoscout]

In the following code, the trait compiles but not the struct implementing it:

#![feature(async_fn_in_trait)]

use std::future::Future;
pub trait Pool {
    type Conn;

    async fn async_callback<'a,
        F: FnOnce(&'a Self::Conn) -> Fut,
        Fut: Future<Output = ()>,
    >(&'a self, callback: F) -> ();
}

pub struct PoolImpl;
pub struct ConnImpl;

impl Pool for PoolImpl {
    type Conn = ConnImpl;

    async fn async_callback<'a,
        F: FnOnce(&'a Self::Conn) -> Fut,
        Fut: Future<Output = ()>,
    >(&'a self, callback: F) -> () {
        todo!()
    }
}

I expected to see this happen:
The code should compile and the expected lifetime of Self::Conn should be 'a.

Instead, this happened:
The compilation fails. The error says that the expected lifetime of Self::Conn in the struct is 'static even if it is declared as 'a in the trait:

error[E0308]: mismatched types
  --> src/lib.rs:19:5
   |
19 | /     async fn async_callback<'a,
20 | |         F: FnOnce(&'a Self::Conn) -> Fut,
21 | |         Fut: Future<Output = ()>,
22 | |     >(&'a self, callback: F) -> () {
   | |__________________________________^ lifetime mismatch
   |
   = note: expected trait `FnOnce<(&'static ConnImpl,)>`
              found trait `FnOnce<(&'a ConnImpl,)>`
note: the lifetime `'a` as defined here...
  --> src/lib.rs:19:29
   |
19 |     async fn async_callback<'a,
   |                             ^^
   = note: ...does not necessarily outlive the static lifetime

Please note that the code compiles if you remove the async modifier from both the trait and the struct.

Meta

rustc --version --verbose:

rustc 1.67.0-nightly (83356b78c 2022-11-17)
binary: rustc
commit-hash: 83356b78c4ff3e7d84e977aa6143793545967301
commit-date: 2022-11-17
host: x86_64-unknown-linux-gnu
release: 1.67.0-nightly
LLVM version: 15.0.4

[compiler-errors]

This issue title is not related to the code that was provided -- did you copy this issue title from #103352 and forget to reword it?

Anyways, this looks like a duplicate to #102681.

[ufoscout]

@compiler-errors
sorry, I did something wrong with the issue title.

Anyways, this looks like a duplicate to #102681.

I reported this issue because I considered it different than #102681, but you know it better than me, so I am not sure.

[cjgillot]

The code is now accepted, can be closed with a test.