error[E0081]: discriminant value `1isize` already exists
  --> $DIR/issue-15524.rs:15:9
   |
14 |     A = 1,
   |         - first use of `1isize`
15 |     B = 1,
   |         ^ enum already has `1isize`

error[E0081]: discriminant value `1isize` already exists
  --> $DIR/issue-15524.rs:18:5
   |
14 |     A = 1,
   |         - first use of `1isize`
...
18 |     D,
   |     ^ enum already has `1isize`

error[E0081]: discriminant value `1isize` already exists
  --> $DIR/issue-15524.rs:21:9
   |
14 |     A = 1,
   |         - first use of `1isize`
...
21 |     E = N,
   |         ^ enum already has `1isize`

error: aborting due to 3 previous errors