程序包含一个空指针引用。

The program contains a null pointer dereference.

youdao

new函数除了构建一个包括它的对象引用以外，基本上没什么作用。而且您可以看到，其它的函数在执行前必须先将那个空指针解开。

The new function basically does nothing besides building the object reference to contain that, and you can see that the other functions have to unpack the void pointer before getting down to business.

youdao

如果一个指针指向一个不在图中的对象，那么此对象就是一个不可到达的对象，垃圾收集器就将短弱引用表相应的槽置空。

If a pointer pointing to an object not in the graph, then the object is not a reachable object, and then garbage collector sets the slot to null in the short weak reference table.

youdao