error[E0277]: the size for values of type `A` cannot be known at compilation time
  --> $DIR/issue-88287.rs:34:9
   |
LL | type SearchFutureTy<'f, A, B: 'f>
   |                         - this type parameter needs to be `Sized`
...
LL |         async move { todo!() }
   |         ^^^^^^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time
   |
note: required by a bound in `<T as SearchableResourceExt<Criteria>>`
  --> $DIR/issue-88287.rs:24:6
   |
LL | impl<T, Criteria> SearchableResourceExt<Criteria> for T
   |      ^ required by this bound in `<T as SearchableResourceExt<Criteria>>`
help: consider removing the `?Sized` bound to make the type parameter `Sized`
   |
LL -     A: SearchableResource<B> + ?Sized + 'f,
LL +     A: SearchableResource<B> + 'f,
   |
help: consider relaxing the implicit `Sized` restriction
   |
LL |     T: SearchableResource<Criteria> + ?Sized,
   |                                     ++++++++

error: aborting due to previous error

For more information about this error, try `rustc --explain E0277`.