rust-lang / rust-lang/rust-clippy

`infinite-loop` and `never_loop` trigger on the same loop 😆

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C-bug I-false-positive L-correctness L-restriction
Dominant language
Rust
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Description

#![warn(clippy::infinite_loop, clippy::never_loop)]
fn main() {
    'outer2: loop {
        let _: i32 = loop { loop { break 'outer2 } };
    }
}
...
warning: this loop never actually loops
 --> a.rs:4:22
  |
4 |         let _: i32 = loop { loop { break 'outer2 } };
  |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |
  = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#never_loop

warning: infinite loop detected
 --> a.rs:4:22
  |
4 |         let _: i32 = loop { loop { break 'outer2 } };
  |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |
  = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#infinite_loop
note: the lint level is defined here
...

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Research direction

Start by reproducing the supplied Rust snippet with both clippy::infinite_loop and clippy::never_loop enabled, then inspect the implementations of those two lints and their existing tests. Determine the intended diagnostic for this control flow and verify that the final behavior is consistent rather than producing contradictory reports.

Written by the indexing model from the issue text.

Assessment

Tech stack
rust
Domain
devtools
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
45/100

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