error[E0308]: mismatched types
  --> $DIR/or-patter-mismatch.rs:15:68
   |
LL | fn main() { match blah::a(1, 1, 2) { blah::a(_, x, y) | blah::b(x, y) => { } } }
   |                                                                    ^ expected usize, found isize
   |
   = note: expected type `usize`
              found type `isize`

error: aborting due to previous error

For more information about this error, try `rustc --explain E0308`.