Incorrect MIR printed with `--emit=mir` when a closure captures multiple fields of a single value.

// WARNING: This output format is intended for human consumers only
// and is subject to change without notice. Knock yourself out.
// HINT: See also -Z dump-mir for MIR at specific points during compilation.
fn foo(_1: (String, String)) -> () {
    debug x => _1;
    let mut _0: ();
    let _2: {closure@src/lib.rs:2:20: 2:22};
    let mut _3: &std::string::String;
    scope 1 {
        debug _closure => _2;
    }

    bb0: {
        _3 = &(_1.1: std::string::String);
        _2 = {closure@src/lib.rs:2:20: 2:22} { x: move (_1.0: std::string::String) };
        drop(_2) -> [return: bb1, unwind: bb4];
    }

    bb1: {
        drop((_1.1: std::string::String)) -> [return: bb3, unwind continue];
    }

    bb2 (cleanup): {
        resume;
    }

    bb3: {
        return;
    }

    bb4 (cleanup): {
        drop((_1.1: std::string::String)) -> [return: bb2, unwind terminate(cleanup)];
    }
}

fn foo::{closure#0}(_1: {closure@src/lib.rs:2:20: 2:22}) -> () {
    debug x__0 => (_1.0: std::string::String);
    debug x__1 => (*(_1.1: &std::string::String));
    let mut _0: ();
    let mut _2: bool;
    let _3: std::string::String;
    let mut _4: &std::string::String;
    let mut _5: bool;
    scope 1 {
        debug _a => _4;
    }
    scope 2 {
        debug _b => _3;
    }

    bb0: {
        _5 = const false;
        _5 = const true;
        _2 = std::hint::black_box::<bool>(const true) -> [return: bb1, unwind: bb9];
    }

    bb1: {
        switchInt(move _2) -> [0: bb3, otherwise: bb2];
    }

    bb2: {
        _4 = copy (_1.1: &std::string::String);
        goto -> bb4;
    }

    bb3: {
        _5 = const false;
        _3 = move (_1.0: std::string::String);
        drop(_3) -> [return: bb4, unwind: bb9];
    }

    bb4: {
        switchInt(copy _5) -> [0: bb6, otherwise: bb7];
    }

    bb5 (cleanup): {
        resume;
    }

    bb6: {
        return;
    }

    bb7: {
        drop((_1.0: std::string::String)) -> [return: bb6, unwind continue];
    }

    bb8 (cleanup): {
        drop((_1.0: std::string::String)) -> [return: bb5, unwind terminate(cleanup)];
    }

    bb9 (cleanup): {
        switchInt(copy _5) -> [0: bb5, otherwise: bb8];
    }
}