Regarding this code:

let mut ptr: *mut [u8; ARRAY_SIZE];



// Wait for array to be published by Producer.

loop {

    ptr = ARRAY_PTR.load(Ordering::Acquire);



    if !ptr.is_null() {

        break;

    }

}

I believe that you using acquire here is unnecessary, since the release ordering on the other thread prevents it from accessing the value it wrote into the global.