Casting pointer to derived class to reference to pointer to base class

Question

Why I can\'t cast a pointer to derived class to reference to pointer to base class?

struct Base { };
struct Derived : Base { };

int main()
{
    Derived* de         


        

Answer 1

As per your comment:

"No, it is not an academic question. I need to call a function taking as argument Base*&"

The correct way to resolve this is to create a new pointer variable of the appropriate type, and pass that (or rather, a reference to it) to the function in question:

struct Base { };
struct Derived : Base { };

int main()
{
    Derived* derived = nullptr;
    Base* base = static_cast(derived);
    my_function(base); // takes a Base*& argument

    // If you need the pointer value and are sure that
    // it's a Derived* type:
    derived = static_cast(base);
}

Note that you would likely have received this answer sooner if you had included the pertinent information (from the comment I quoted above) in the question itself.