Rust errors / Names, paths and imports
Rust compiler error · checked with rustc 1.99.0
Rust error E0426: use of undeclared label `'a`
What it meansAn undeclared label was used.
What rustc prints
error[E0426]: use of undeclared label `'a`
--> main.rs:4:11
|
4 | break 'a; // error: use of undeclared label `'a`
| ^^ undeclared label `'a`Real output of rustc 1.99.0 compiling the official example below (2021 edition). Your names and line numbers will differ; the first line is the part to match.
E0426Names, paths and imports
Activein rustc 1.99.0
6related errors linked below
The compiler team's explanation
An undeclared label was used.
Erroneous code example:
loop {
break 'a; // error: use of undeclared label `'a`
}Please verify you spelled or declared the label correctly. Example:
'a: loop {
break 'a; // ok!
}From rustc --explain E0426 (1.99.0), part of the Rust project, MIT or Apache-2.0. Official page.
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