error[E0081]: discriminant value `0` assigned more than once
  --> $DIR/enum-discrim-autosizing.rs:6:1
   |
LL | / enum Eu64 {
LL | |
LL | |     Au64 = 0,
   | |            - first assignment of `0`
LL | |
LL | |     Bu64 = 0x8000_0000_0000_0000
   | |            --------------------- second assignment of `0` (overflowed from `9223372036854775808`)
LL | |
LL | | }
   | |_^

error: aborting due to previous error

For more information about this error, try `rustc --explain E0081`.