Code shared from the Rust Playground

playground.rs

fn cast_slice(slice: &[i8]) -> &[u8] {
    unsafe { std::slice::from_raw_parts(slice.as_ptr().cast(), slice.len()) }
}

fn main() {
    let array: [i8; 256] = [0; 256];
    let slice: &[u8] = cast_slice(&array[..]);
    println!("{:?}", slice);
}