调用update函数删除对象后，关闭程序报错，求指导

Cocos2d-x
#1

执行之后，关闭程序报错，怎么解决？

void HWorld::myupdate(float dt){

    auto onebullet = getChildByTag(922);
    auto oneEnemy = getChildByTag(900);


    if(onebullet->getPositionY() <400){

    onebullet->setPositionY(onebullet->getPositionY() + 1);
    if(onebullet->boundingBox().intersectsRect(oneEnemy->boundingBox())){
    onebullet->setPositionY(onebullet->getPositionY());
    this->removeChild(onebullet,true);
    this->removeChild(oneEnemy,true);
    unschedule(schedule_selector(HWorld::myupdate));

    }
    }


```
#2

原来是 有特么的看不见的字符 - - ！