VAPS XT入门教程20.01：inaccessible within this context

在Linux PC/RK3588S下编译软件依赖库时会出现这个错误。

In file included from ../vxtBaseClsVideoController.h:32,
                 from ../vxtBaseClsVideoController.cpp:11:
/home/hyper/VAPS_XT_4_2_1/src/XTObjects/VideoObjects/VideoSourceTableElement/vxtClsVideoSourceTableElement.h: At global scope:
/home/hyper/VAPS_XT_4_2_1/src/XTObjects/VideoObjects/VideoSourceTableElement/vxtClsVideoSourceTableElement.h:142:71: error: ‘class vxtRTDoubleListNodeT<vxtRTObject> vxtRTDoubleListNodeT<vxtRTObject>::vxtRTDoubleListNodeT’ is inaccessible within this context
  142 | ct VXTCLSVIDEOSOURCETABLEELEMENT_SPEC ObserverNode : public vxtRTDoubleListNodeT<ObserverNode>
      |                                                             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

In file included from /home/hyper/VAPS_XT_4_2_1/src/RT/include/vxtRTObject.h:46,
                 from /home/hyper/VAPS_XT_4_2_1/src/RT/include/vxtRTTableElement.h:55,
                 from /home/hyper/VAPS_XT_4_2_1/src/XTObjects/VideoObjects/VideoSourceTableElement/vxtBaseClsVideoSourceTableElement.h:35,
                 from /home/hyper/VAPS_XT_4_2_1/src/XTObjects/VideoObjects/VideoSourceTableElement/vxtClsVideoSourceTableElement.h:35,
                 from ../vxtBaseClsVideoController.h:32,
                 from ../vxtBaseClsVideoController.cpp:11:

找到/home/hyper/VAPS_XT_4_2_1/src/XTObjects/VideoObjects/VideoSourceTableElement/vxtClsVideoSourceTableElement.h的142行

private:
   struct ObserverNode;
   struct VXTCLSVIDEOSOURCETABLEELEMENT_SPEC ObserverNode : public vxtRTDoubleListNodeT<ObserverNode>
   {
       ObserverNode() : pObj(VXT_NULL) {}

      ObserverI *pObj;
   };

   // Disallow copy
   Index(const Index &a_rOther);
   Index& operator = (const Index &a_rOther);

   ObserverNode m_ObserverNode;