QML segfault

$ qmlscene --verbose crash.qml

Qt 5.7.1 (x86_64-little_endian-lp64 shared (dynamic) release build; by GCC 6.3.0 20170124)Segmentation fault (core dumped)

import QtQuick 2.5
import QtQuick.Layouts 1.1
import QtQuick.Controls 1.4

ApplicationWindow {
  Component.onCompleted: x(1)
  function x(x, y) {
    function z() {
        if (y != null) {
          y()
        }
    }
    z()
  }
}