Some code does not round-trip. This JS terminates but if I convert the resulting CS back to JS, I get an infinite loop.

    function test() {
        var i;
        var countdown = function(n) {
            var i;
            for (var i = n; i > 0; i--) {
                console.log(i);
            }
        }
        for (var i = 0; i < 10; i++) {
            countdown(i);
        }
    } 
    test();