error[E0603]: enum `Y` is private
  --> $DIR/export-tag-variant.rs:7:26
   |
LL | fn main() { let z = foo::Y::Y1; }
   |                          ^ private enum
   |
note: the enum `Y` is defined here
  --> $DIR/export-tag-variant.rs:4:5
   |
LL |     enum Y { Y1 }
   |     ^^^^^^

error: aborting due to previous error

For more information about this error, try `rustc --explain E0603`.