class Base
{
    public:
    int base_int;
};

class Derived : public Base
{
    public:
    int derived_int;
};

Base* basepointer = new Derived();
basepointer-> //Access derived_int here, is it possible? If so, then how?

Derived* derivedpointer = new Derived;
derivedpointer->base_int; // You can access this just fine

Base* basepointer = new Derived;
static_cast<Derived*>(basepointer)->derived_int; // Can now access, because we have a derived pointer

class Derived : public Base

class Base
{
protected:
 virtual int &GetInt()
 {
  //Die horribly
 }

public:
 int base_int;
};

class Derived : Base
{
  int &GetInt()
  {
    return derived_int;
  }
public:
int derived_int
};

basepointer->GetInt() = 0;

template<typename DerivedT>
class Base
{
public:
    int accessDerivedField()
    {
        auto derived = static_cast<DerivedT*>(this);
        return derived->field;
    }
};


class Derived : public Base<Derived>
{
public:
    int field;
};

int main()
{
    auto obj = new Derived;
    obj->accessDerivedField();
}