error: invalid label name `'_`
  --> $DIR/label-underscore.rs:12:5
   |
LL |     '_: loop { //~ ERROR invalid label name `'_`
   |     ^^

error: invalid label name `'_`
  --> $DIR/label-underscore.rs:13:15
   |
LL |         break '_ //~ ERROR invalid label name `'_`
   |               ^^

error: aborting due to 2 previous errors