src/test/ui/unconstrained-ref.stderr

   1 error[E0282]: type annotations needed
   2   --> $DIR/unconstrained-ref.rs:6:5
   3    |
   4 LL |     S { o: &None };
   5    |     ^^^^^^^^^^^^^^ cannot infer type of the type parameter `T` declared on the struct `S`
   6    |
   7 help: consider specifying the generic argument
   8    |
   9 LL |     S::<T> { o: &None };
  10    |      +++++
  11
  12 error: aborting due to previous error
  13
  14 For more information about this error, try `rustc --explain E0282`.