error[E0401]: can't use generic parameters from outer function
  --> $DIR/issue-98432.rs:5:34
   |
LL | impl<T> Struct<T> {
   |      - type parameter from outer function
LL |     const CONST: fn() = || {
LL |         struct _Obligation where T:;
   |                           -      ^ use of generic parameter from outer function
   |                           |
   |                           help: try using a local generic parameter instead: `<T>`

error: aborting due to previous error

For more information about this error, try `rustc --explain E0401`.