error[E0308]: mismatched types
  --> $DIR/issue-67945-2.rs:12:20
   |
LL | struct Bug<S> {
   |            - this type parameter
...
LL |         let x: S = MaybeUninit::uninit();
   |                -   ^^^^^^^^^^^^^^^^^^^^^ expected type parameter `S`, found union `MaybeUninit`
   |                |
   |                expected due to this
   |
   = note: expected type parameter `S`
                       found union `MaybeUninit<_>`

error[E0392]: parameter `S` is never used
  --> $DIR/issue-67945-2.rs:9:12
   |
LL | struct Bug<S> {
   |            ^ unused parameter
   |
   = help: consider removing `S`, referring to it in a field, or using a marker such as `PhantomData`

error: aborting due to 2 previous errors

Some errors have detailed explanations: E0308, E0392.
For more information about an error, try `rustc --explain E0308`.