False positive for the useless_attribute rule

[recmo]

I tried this code:

#[allow(clippy::wildcard_imports)]
use std::prelude::v1::*;

I expected to see this happen: explanation

Nothing, since this is an exception to the wildcard_imports rule, required because of #5917.

Instead, this happened: explanation

error: useless lint attribute
 --> utils/mmap-vec/src/mmap_vec.rs:5:1
  |
5 | #[allow(clippy::wildcard_imports)]
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: if you just forgot a `!`, use: `#![allow(clippy::wildcard_imports)]`
  |
  = note: `-D clippy::useless-attribute` implied by `-D warnings`
  = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#useless_attribute

Meta

• cargo clippy -V: clippy 0.0.212 (7e6d6e5 2020-08-16)
• rustc -Vv:

  rustc 1.47.0-nightly (7e6d6e5f5 2020-08-16)
  binary: rustc
  commit-hash: 7e6d6e5f535321c2223f044caba16f97b825009c
  commit-date: 2020-08-16
  host: x86_64-apple-darwin
  release: 1.47.0-nightly
  LLVM version: 10.0
  

Backtrace

<backtrace>

[recmo]

Same for #[allow(clippy::enum_glob_use)]