Open
Description
Using the following flags
--force-warn clippy::never_loop
this code:
fn main() {
'a: for _ in 0..1 { break 'a; }
'a: for _ in 0..1 { break 'a; }
}caused the following diagnostics:
Checking _snippet_149 v0.1.0 (/tmp/icemaker_global_tempdir.VQhomPU3g4RT/icemaker_clippyfix_tempdir.kAAqrUJknTKl/_snippet_149)
warning: this loop never actually loops
--> src/main.rs:2:5
|
2 | 'a: for _ in 0..1 { break 'a; }
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#never_loop
= note: requested on the command line with `--force-warn clippy::never-loop`
help: if you need the first element of the iterator, try writing
|
2 - 'a: for _ in 0..1 { break 'a; }
2 + if let Some(_) = (0..1).next() { break 'a; }
|
warning: this loop never actually loops
--> src/main.rs:3:5
|
3 | 'a: for _ in 0..1 { break 'a; }
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#never_loop
help: if you need the first element of the iterator, try writing
|
3 - 'a: for _ in 0..1 { break 'a; }
3 + if let Some(_) = (0..1).next() { break 'a; }
|
warning: `_snippet_149` (bin "_snippet_149") generated 2 warnings
Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.11s
However after applying these diagnostics, the resulting code:
fn main() {
if let Some(_) = (0..1).next() { break 'a; }
if let Some(_) = (0..1).next() { break 'a; }
}no longer compiled:
Checking _snippet_149 v0.1.0 (/tmp/icemaker_global_tempdir.VQhomPU3g4RT/icemaker_clippyfix_tempdir.kAAqrUJknTKl/_snippet_149)
error[E0426]: use of undeclared label `'a`
--> src/main.rs:2:44
|
2 | if let Some(_) = (0..1).next() { break 'a; }
| ^^ undeclared label `'a`
error[E0426]: use of undeclared label `'a`
--> src/main.rs:3:44
|
3 | if let Some(_) = (0..1).next() { break 'a; }
| ^^ undeclared label `'a`
error[E0268]: `break` outside of a loop or labeled block
--> src/main.rs:2:38
|
2 | if let Some(_) = (0..1).next() { break 'a; }
| ^^^^^^^^ cannot `break` outside of a loop or labeled block
error[E0268]: `break` outside of a loop or labeled block
--> src/main.rs:3:38
|
3 | if let Some(_) = (0..1).next() { break 'a; }
| ^^^^^^^^ cannot `break` outside of a loop or labeled block
Some errors have detailed explanations: E0268, E0426.
For more information about an error, try `rustc --explain E0268`.
error: could not compile `_snippet_149` (bin "_snippet_149" test) due to 4 previous errors
warning: build failed, waiting for other jobs to finish...
error: could not compile `_snippet_149` (bin "_snippet_149") due to 4 previous errors
Version:
rustc 1.89.0-nightly (44f415c1d 2025-06-06)
binary: rustc
commit-hash: 44f415c1d617ebc7b931a243b7b321ef8a6ca47c
commit-date: 2025-06-06
host: x86_64-unknown-linux-gnu
release: 1.89.0-nightly
LLVM version: 20.1.5