tests/rustdoc-ui/rustc-check-passes.stderr

   1 error[E0636]: the feature `rustdoc_internals` has already been declared
   2   --> $DIR/rustc-check-passes.rs:2:12
   3    |
   4 LL | #![feature(rustdoc_internals)]
   5    |            ^^^^^^^^^^^^^^^^^
   6
   7 error: aborting due to previous error
   8
   9 For more information about this error, try `rustc --explain E0636`.