error: `[u8; 1 + 2]` is forbidden as the type of a const generic parameter --> $DIR/issue-74101.rs:6:18 | LL | fn test() {} | ^^^^^^^^^^^ | = note: the only supported types are integers, `bool` and `char` = help: add `#![feature(adt_const_params)]` to the crate attributes to enable more complex and user defined types error: `[u8; 1 + 2]` is forbidden as the type of a const generic parameter --> $DIR/issue-74101.rs:9:21 | LL | struct Foo; | ^^^^^^^^^^^ | = note: the only supported types are integers, `bool` and `char` = help: add `#![feature(adt_const_params)]` to the crate attributes to enable more complex and user defined types error: aborting due to 2 previous errors