error[E0106]: missing lifetime specifier --> $DIR/lifetime-in-const-param.rs:5:23 | LL | struct S<'a, const N: S2>(&'a ()); | ^^ expected named lifetime parameter error: `S2<'_>` is forbidden as the type of a const generic parameter --> $DIR/lifetime-in-const-param.rs:5:23 | LL | struct S<'a, const N: S2>(&'a ()); | ^^ | = note: the only supported types are integers, `bool` and `char` = help: more complex types are supported with `#![feature(adt_const_params)]` error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0106`.