error[E0453]: allow(unused) incompatible with previous forbid
  --> $DIR/forbid-member-group.rs:6:9
   |
LL | #![forbid(unused_variables)]
   |           ---------------- `forbid` level set here
LL |
LL | #[allow(unused)]
   |         ^^^^^^ overruled by previous forbid

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0453`.