subclass pointer convert2 parent class pointer issue

subclass_pointer_convert2_parentclass_pointer.cc

#include<iostream>

class CPartialBase {
public:

    CPartialBase() {
        std::cout << "CPartialBase this:" << this << std::endl;
    }

    virtual void funcPart() = 0;
};

class CPartialDerive: public CBase1,public CPartialBase {
public:

    CPartialDerive() {
        std::cout << "CPartialDerive this:" << this << std::endl;
    }

    virtual void funcPart() override {
        std::cout << "funcPart called,this:" <<this << std::endl;
    }
};


int main(int argc, char** argv){

    CPartialDerive * _pd = new CPartialDerive();

    CPartialBase* _pb = (CPartialBase*)_pd;

    void * _p_tmp = _pd;

    CPartialBase* _pbx = (CPartialBase*)_p_tmp;

    /*This will causing the runtime error:

     'Run-Time Check Failure #0 - The value of ESP was not properly saved across a function call.This
     is usually a result of calling a function declared with one calling convention with a function
     pointer declared with a different calling convention.'

     This is because _pbx didn't point to the 'CPartialBase' part of the 'CPartialDerive' object.  */

    //_pbx->funcPart();

    //And this simply can't compile.
    //CPartialBase* _pby = dynamic_cast<CPartialBase*>(_p_tmp);

    _pb->funcPart();

    return 0;