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Error code E0767

An unreachable label was used.

Erroneous code example:

#![allow(unused)] fn main() { 'a: loop { || { loop { break 'a } // error: use of unreachable label `'a` }; } }

Ensure that the label is within scope. Labels are not reachable through functions, closures, async blocks or modules. Example:

#![allow(unused)] fn main() { 'a: loop { break 'a; // ok! } }