Invalid feature suggestion: #[feature(const_generics)]

[DutchGhost]

When writing a const generic that uses a type other than bool, char or integer, the compiler generates the following error message:

error: `std::sync::atomic::Ordering` is forbidden as the type of a const generic parameter
 --> src/lib.rs:5:21
  |
5 | struct Bug<const O: atomic::Ordering>;
  |                     ^^^^^^^^^^^^^^^^
  |
  = note: the only supported types are integers, `bool` and `char`
  = help: more complex types are supported with `#[feature(const_generics)]`

However, this error message is wrong, as its missing a ! in the feature suggestion.
It should be #![feature(const_generics)] rather than #[feature(const_generics)]

[tesuji]

One just need to change this line:

rust/compiler/rustc_typeck/src/check/wfcheck.rs

Line 333 in 61f5a00

.help("more complex types are supported with `#[feature(const_generics)]`")

then bless respective stderr files.

[varkor]

then bless respective stderr files.

One doesn't even need to build the compiler: a search and replace for #[feature(const_generics)] in src/test would be enough.

[jakevossen5]

I can do this quick if that's okay.