#![allow(dead_code, deprecated, unused_variables, unused_mut)]
use core::ops::{Deref, DerefMut};
struct SomeType;
impl Deref for SomeType {
    type Target = [u8];
    fn deref(&self) -> &[u8] {
        &[]
    }
}
impl DerefMut for SomeType {
    fn deref_mut(&mut self) -> &mut [u8] {
        &mut []
    }
}
impl<T> AsMut<T> for SomeType
where
    <SomeType as Deref>::Target: AsMut<T>,
{
    fn as_mut(&mut self) -> &mut T {
        self.deref_mut().as_mut()
    }
}
fn main() {}