Rust error E0657: `impl Trait` cannot capture higher-ranked lifetime from outer `impl Trait`

What rustc prints

error[E0657]: `impl Trait` cannot capture higher-ranked lifetime from outer `impl Trait`
  --> main.rs:15:53
   |
15 | fn opaque() -> impl for<'a> BorrowInto<'a, Target = impl Sized + 'a> {
   |                                                     ^^^^^^^^^^^^^--
   |                                                     |
   |                                                     `impl Trait` implicitly captures all lifetimes in scope
   |
note: lifetime declared here
  --> main.rs:15:25
   |
15 | fn opaque() -> impl for<'a> BorrowInto<'a, Target = impl Sized + 'a> {
   |                         ^^

Real output of rustc 1.99.0 compiling the official example below (2021 edition). Your names and line numbers will differ; the first line is the part to match.

trait BorrowInto<'a> {
    type Target;

    fn borrow_into(&'a self) -> Self::Target;
}

impl<'a> BorrowInto<'a> for () {
    type Target = &'a ();

    fn borrow_into(&'a self) -> Self::Target {
        self
    }
}

fn opaque() -> impl for<'a> BorrowInto<'a, Target = impl Sized + 'a> {
    ()
}

Related errors

• E0382borrow of moved value
• E0499cannot borrow as mutable more than once at a time
• E0502cannot borrow as mutable because it is also borrowed as immutable
• E0106missing lifetime specifier
• E0626This error occurs because a borrow in a movable coroutine persists across a yield point
• E0637`'_` cannot be used here
• E0700hidden type for `impl Trait<'y>` captures lifetime that does not appear in bounds
• E0712thread-local variable borrowed past end of function

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