main.cpp:222:49: error: ‘BufferB’ is an inaccessible base of ‘BufferA’
     BufferB* buftab[3] = {prodAb, prodCb, prodCb};
                                                 ^
main.cpp:222:49: error: ‘BufferB’ is an inaccessible base of ‘BufferC’

===================================
  BufferB* prodBb;
  BufferA* prodAb;
  BufferC* prodCb;



BufferB* buftab[3] = {prodAb, prodCb, prodCb};