Suggest removing a borrow to fix lifetime error (replacing autoderef'ed expr with a mut-coercible expr)

Code

fn foo(r: &mut i32) -> &i32 {
    &r
}

Current output

error[E0515]: cannot return reference to function parameter `r`
 --> src/bin/main.rs:4:5
  |
4 |     &r
  |     ^^ returns a reference to data owned by the current function

For more information about this error, try `rustc --explain E0515`.
error: could not compile `quick-rs` (bin "main") due to 1 previous error

Desired output

error[E0515]: cannot return reference to function parameter `r`
 --> src/bin/main.rs:4:5
  |
4 |     &r
  |     ^ help: remove this ref
  |     ^^ returns a reference to data owned by the current function

For more information about this error, try `rustc --explain E0515`.
error: could not compile `quick-rs` (bin "main") due to 1 previous error

Rationale and extra context

No response

Other cases

Rust Version

rustc 1.91.0-nightly (040a98af7 2025-08-20)
binary: rustc
commit-hash: 040a98af70f0a7da03f3d5356531b28a2a7a77e4
commit-date: 2025-08-20
host: aarch64-unknown-linux-gnu
release: 1.91.0-nightly
LLVM version: 21.1.0

Anything else?

No response

Start with the reproducer in src/bin/main.rs and run it against the reported Rust version to confirm the E0515 diagnostic. Trace the compiler's E0515 diagnostic handling and add coverage for this case, with done defined as emitting the suggested “remove this ref” help text shown in the issue.