GC crash in dev branch

import QtQuick 2.6

Item {
    id: root
    property int count: 10000;
    property var items: [];

    Component {
        id: component;
        QtObject {
        }
    }

    Timer {
        interval: 1
        repeat: true
        running: true
        onTriggered: allocate()
    }

    property int iterations: 0
    function allocate() {
        console.log(++iterations)
        for (var i=0; i<items.length; ++i) {
            items[i].destroy();
        }

        for (var i=0; i<root.count; ++i) {
            var object = component.createObject();
            items[i] = object
        }
    }
}