foo.mir

fn foo(_1: std::option::Option<&i32>) -> () {
    let mut _0: ();                      // return pointer
    scope 1 {
        let _2: std::option::Option<&i32>; // "v" in scope 1 at <anon>:5:8: 5:9
        scope 2 {
            let _3: &i32;                // "x" in scope 2 at <anon>:8:14: 8:15
        }
    }
    let mut _4: i32;

    bb0: {
        StorageLive(_2);                 // scope 0 at <anon>:5:8: 5:9
        _2 = _1;                         // scope 0 at <anon>:5:8: 5:9
        switch(_2) -> [None: bb1, Some: bb2]; // scope 1 at <anon>:7:9: 7:13
    }

    bb1: {
        _0 = ();                         // scope 1 at <anon>:7:17: 7:19
        goto -> bb3;                     // scope 1 at <anon>:6:5: 9:6
    }

    bb2: {
        StorageLive(_3);                 // scope 1 at <anon>:8:14: 8:15
        _3 = ((_2 as Some).0: &i32);     // scope 1 at <anon>:8:14: 8:15
        StorageLive(_4);                 // scope 2 at <anon>:8:24: 8:26
        _4 = (*_3);                      // scope 2 at <anon>:8:24: 8:26
        _0 = bar(_4) -> bb4;             // scope 2 at <anon>:8:20: 8:27
    }

    bb3: {
        StorageDead(_3);                 // scope 1 at <anon>:9:6: 9:6
        StorageDead(_2);                 // scope 0 at <anon>:10:2: 10:2
        return;                          // scope 1 at <anon>:10:2: 10:2
    }

    bb4: {
        StorageDead(_4);                 // scope 2 at <anon>:8:27: 8:27
        goto -> bb3;                     // scope 1 at <anon>:6:5: 9:6
    }
}

foo.rs

fn bar(i: i32) {
    println!("{}", i);
}

fn foo(v: Option<&i32>) {
    match v {
        None => {},
        Some(x) => bar(*x),
    }
}

fn main() {
    foo(Some(&5));
}