src/test/ui/issues/issue-11515.stderr

   1 error[E0658]: trait upcasting coercion is experimental
   2   --> $DIR/issue-11515.rs:9:33
   3    |
   4 LL |     let test = box Test { func: closure };
   5    |                                 ^^^^^^^
   6    |
   7    = note: see issue #65991 <https://github.com/rust-lang/rust/issues/65991> for more information
   8    = help: add `#![feature(trait_upcasting)]` to the crate attributes to enable
   9
  10 error: aborting due to previous error
  11
  12 For more information about this error, try `rustc --explain E0658`.