use lazy_static::lazy_static;
use std::sync::{Arc, Mutex};

#[derive(Clone)]
struct Struct {}

lazy_static! {
    static ref STRUCT: Arc<Mutex<Option<Struct>>> = Arc::new(Mutex::new(None));
}

fn main()
{
    let mut s = STRUCT.lock().unwrap();
    *s = Some(Struct{});
}