error[E0308]: mismatched types
  --> $DIR/hidden-child.rs:9:26
   |
LL |     let x: Option<i32> = 1i32;
   |            -----------   ^^^^ expected `Option<i32>`, found `i32`
   |            |
   |            expected due to this
   |
   = note: expected enum `Option<i32>`
              found type `i32`
help: try wrapping the expression in `hidden_child::__private::Some`
   |
LL |     let x: Option<i32> = hidden_child::__private::Some(1i32);
   |                          ++++++++++++++++++++++++++++++    +

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0308`.