must_use_unit fails to apply if it's one of many attrs

[matthiaskrgr]

Summary

.

Reproducer

I tried this code:

#[cfg_attr(all(), must_use, deprecated)]
fn main() { }

warning: this unit-returning function has a `#[must_use]` attribute
 --> src/main.rs:2:1
  |
1 | #[cfg_attr(all(), must_use, deprecated)]
  |                   -------- help: remove the attribute
2 | fn main() { }
  | ^^^^^^^^^
  |
  = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#must_use_unit
  = note: `#[warn(clippy::must_use_unit)]` on by default

in this case we need to remove the "," as well otherwise we end up with a syntax error lol

error: expected identifier, found `,`
 --> src/main.rs:1:19
  |
1 | #[cfg_attr(all(), , deprecated)]
  |                   ^
  |                   |
  |                   expected identifier
  |                   help: remove this comma

Version

rustc 1.78.0-nightly (3246e7951 2024-02-19)
binary: rustc
commit-hash: 3246e79513cb89ddbfc0f21cb5a877e5b321dcc5
commit-date: 2024-02-19
host: x86_64-unknown-linux-gnu
release: 1.78.0-nightly
LLVM version: 18.1.0

Additional Labels

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