1 error[E0426]: use of undeclared label `'x`
2 --> $DIR/hygienic-label-3.rs:2:19
4 LL | () => { break 'x; }
5 | ^^ undeclared label `'x`
8 | ------ in this macro invocation
10 = note: this error originates in the macro `foo` (in Nightly builds, run with -Z macro-backtrace for more info)
12 error: aborting due to previous error
14 For more information about this error, try `rustc --explain E0426`.