error: Invalid variant for enum `Enum`: D
 --> tests/compilation_failure_tests/iteration_order/invalid_variant.rs:4:18
  |
4 | #[iteration_order(A, B, D)]
  |                  ^^^^^^^^^
  |
  = note: The iteration order can only contain variants of `Enum`

error[E0601]: `main` function not found in crate `$CRATE`
 --> tests/compilation_failure_tests/iteration_order/invalid_variant.rs:7:2
  |
7 | }
  |  ^ consider adding a `main` function to `$DIR/tests/compilation_failure_tests/iteration_order/invalid_variant.rs`