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//@ known-bug: #101557
//@ compile-flags: -Copt-level=0
#![feature(generic_const_exprs)]
use std::marker::PhantomData;
trait Trait {
const CONST: usize;
}
struct A<T: Trait> {
_marker: PhantomData<T>,
}
impl<const N: usize> Trait for [i8; N] {
const CONST: usize = N;
}
impl<const N: usize> From<usize> for A<[i8; N]> {
fn from(_: usize) -> Self {
todo!()
}
}
impl<T: Trait> From<A<[i8; T::CONST]>> for A<T> {
fn from(_: A<[i8; T::CONST]>) -> Self {
todo!()
}
}
fn f<T: Trait>() -> A<T>
where
[(); T::CONST]:,
{
// Usage of `0` is arbitrary
let a = A::<[i8; T::CONST]>::from(0);
A::<T>::from(a)
}
fn main() {
// Usage of `1` is arbitrary
f::<[i8; 1]>();
}
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