Wrong suggestion for const well-formedness of bool

[slanterns]

Code

#![feature(generic_const_exprs)]

fn bb<const N: bool>() {}

fn b<const N: bool>() {
    bb::<{!N}>();
}

fn main() {}

https://play.rust-lang.org/?version=nightly&mode=debug&edition=2021&gist=6c33a1495d719fbc2d8efe30177c3ca4

Current output

help: try adding a `where` bound using this expression: `where [(); {!N}]:`

Desired output

`where [(); !N as usize]:`

Rationale and extra context

The well-formedness shouldn't be written as where [(); {!N}]: when !N is a bool, which doesn't compile. Should cast it to an integral type.

Other cases

No response

Rust Version

1.78.0-nightly (2024-03-11 4a0cc881dcc4d800f106)

Anything else?

No response

[slanterns]

@rustbot label: +A-const-generics +const-generics-bad-diagnostics +F-generic_const_exprs

[rustbot]

Error: Label const-generics-bad-diagnostics can only be set by Rust team members

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[slanterns]

@rustbot label: +A-const-generics +F-generic_const_exprs