`unused_features` false positive on `doc_cfg`

[kpreid]

Code

#![feature(doc_cfg)]

#[cfg(feature = "enabled_feature")]
pub fn foo() {}

Current output

warning: feature `doc_cfg` is declared but not used
 --> src/lib.rs:1:12
  |
1 | #![feature(doc_cfg)]
  |            ^^^^^^^
  |
  = note: `#[warn(unused_features)]` (part of `#[warn(unused)]`) on by default

warning: `scratchpad` (lib) generated 1 warning

Desired output

No warning

Rationale and extra context

The feature modifies rustdoc output regardless of whether #[doc(cfg)] is explicitly used in the source code, so it is not unused.

Rust Version

rustc 1.96.0-nightly (fda6d37bb 2026-03-27)
binary: rustc
commit-hash: fda6d37bb88ee12fd50fa54d15859f1f91b74f55
commit-date: 2026-03-27
host: aarch64-apple-darwin
release: 1.96.0-nightly
LLVM version: 22.1.2

Anything else?

@rustbot label +F-doc_cfg

[Ko496-glitch]

@kpreid hey can i work on this, I am starting to work on diagnostic issues so i can get use to rust env and clippy

[kpreid]

You don’t need my permission or recommendation to work on this issue.

[mu001999]

Seems doc_cfg is only checked in librustdoc