1 error[E0573]: expected type, found built-in attribute `feature`
2 --> $DIR/issue-78654.rs:9:15
4 LL | impl<const H: feature> Foo {
7 error[E0207]: the const parameter `H` is not constrained by the impl trait, self type, or predicates
8 --> $DIR/issue-78654.rs:9:12
10 LL | impl<const H: feature> Foo {
11 | ^ unconstrained const parameter
13 = note: expressions using a const parameter must map each value to a distinct output value
14 = note: proving the result of expressions other than the parameter are unique is not supported
16 error: aborting due to 2 previous errors
18 Some errors have detailed explanations: E0207, E0573.
19 For more information about an error, try `rustc --explain E0207`.