error[E0658]: use of unstable library feature `unsized_const_params`
  --> $DIR/transmute-const-param-static-reference.rs:9:14
   |
LL | struct Const<const P: &'static ()>;
   |              ^^^^^^^^^^^^^^^^^^^^
   |
   = help: add `#![feature(unsized_const_params)]` to the crate attributes to enable
   = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
   = note: required for `&'static ()` to implement `ConstParamTy_`

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0658`.