ices/71805.rs: fixed with errors

[github-actions]

Issue: rust-lang/rust#71805

#![feature(const_generics)]
#![allow(incomplete_features)]

use std::mem::MaybeUninit;

trait CollectSlice<'a>: Iterator {
    fn inner_array<const N: usize>(&mut self) -> [Self::Item; N];

    fn collect_array<const N: usize>(&mut self) -> [Self::Item; N] {
        let result = self.inner_array();
        assert!(self.next().is_none());
        result
    }
}

impl<'a, I: ?Sized> CollectSlice<'a> for I where I: Iterator {
    fn inner_array<const N: usize>(&mut self) -> [Self::Item; N] {
        let mut result: [MaybeUninit<Self::Item>; N] = unsafe {
            MaybeUninit::uninit().assume_init()
        };

        let mut count = 0;
        for (dest, item) in result.iter_mut().zip(self) {
            *dest = MaybeUninit::new(item);
            count += 1;
        }

        assert_eq!(N, count);

        let temp_ptr: *const [MaybeUninit<Self::Item>; N] = &result;
        unsafe { std::ptr::read(temp_ptr as *const [Self::Item; N]) }
    }
}

fn main() {
    let foos = [0_u64; 9].iter().cloned();
    let _bar: [u64; 9] = foos.collect_array::<9_usize>();
}

=== stdout ===
=== stderr ===
error[E0596]: cannot borrow `foos` as mutable, as it is not declared as mutable
  --> /home/runner/work/glacier/glacier/ices/71805.rs:37:26
   |
36 |     let foos = [0_u64; 9].iter().cloned();
   |         ---- help: consider changing this to be mutable: `mut foos`
37 |     let _bar: [u64; 9] = foos.collect_array::<9_usize>();
   |                          ^^^^ cannot borrow as mutable

error: aborting due to previous error

For more information about this error, try `rustc --explain E0596`.
==============