`extern "C" const unsafe fn` does not trigger the "keyword order for functions declaration" note

[cyrgani]

Code

extern "C" const unsafe fn x() {}

Current output

error: expected `{`, found keyword `const`
 --> src/lib.rs:1:12
  |
1 | extern "C" const unsafe fn x() {}
  |            ^^^^^ expected `{`

Desired output

error: expected `fn`, found keyword `const`
 --> src/lib.rs:1:12
  |
1 | extern "C" const unsafe fn x() {}
  | -----------^^^^^
  | |          |
  | |          expected `fn`
  | help: `extern "C"` must come after `const unsafe`: `const unsafe extern "C"`
  |
  = note: keyword order for functions declaration is `pub`, `default`, `const`, `async`, `unsafe`, `extern`

Rationale and extra context

this is also not very relevant. the extra diagnostic is probably not emitted because there are two misplaced tokens (extern "C").

Other cases

Rust Version

rustc 1.88.0-nightly (d6c1e454a 2025-04-21)
binary: rustc
commit-hash: d6c1e454aa8af5e7e59fbf5c4e7d3128d2f99582
commit-date: 2025-04-21
host: x86_64-unknown-linux-gnu
release: 1.88.0-nightly
LLVM version: 20.1.2

Anything else?

No response