static_mut_refs lint suggests to "use a type that relies on interior mutability instead" but the type is already interior mutable

Code

use std::sync::Mutex;

macro_rules! declare_mutex {
    () => {
        static mut MACRO_MUTEX: Mutex<bool> = Mutex::new(false);
    };
}

declare_mutex!();

fn main() {
    let _lock = unsafe { MACRO_MUTEX.lock().unwrap() };
    //~^ ERROR creating a shared reference to mutable static [static_mut_refs]
}

Current output

error: creating a shared reference to mutable static
  --> src/main.rs:12:26
   |
12 |     let _lock = unsafe { MACRO_MUTEX.lock().unwrap() };
   |                          ^^^^^^^^^^^^^^^^^^ shared reference to mutable static
   |
   = note: shared references to mutable statics are dangerous; it's undefined behavior if the static is mutated or if a mutable reference is created for it while the shared reference lives
   = help: use a type that relies on "interior mutability" instead; to read more on this, visit <https://doc.rust-lang.org/reference/interior-mutability.html>
   = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2024/static-mut-references.html>
   = note: `#[deny(static_mut_refs)]` (part of `#[deny(rust_2024_compatibility)]`) on by default

Desired output

I am not sure, but it should not suggest something that the code already does.

Rationale and extra context

Mutex<bool> is a type with interior mutability. It makes no sense to ask users to use a type with interior mutability instead of this one.

This got introduced in https://github.com/rust-lang/rust/pull/151362.

Other cases

Rust Version

1.98.0-nightly
(2026-07-02 c397dae808f70caebab1)

Anything else?

No response

Start with the reproducer in src/main.rs and run it with the static_mut_refs lint enabled on the reported nightly version. Read the diagnostic changes introduced by pull request 151362 and trace the lint's help message for Mutex. Done means the diagnostic no longer recommends interior mutability when the referenced type already provides it.