rvalue reference factory?

From:
frank67x@googlemail.com
Newsgroups:
comp.lang.c++.moderated
Date:
Mon, 12 May 2014 15:50:00 -0700 (PDT)
Message-ID:
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Is it possible in c++11 to have a factory function that returns
rvalue references of base class types?
I didn't succeed this the example below.
It generates core dump on linux.
My "real" application - where i extracted the example from -
does a bit different:
 pure virtual method called
 terminate called without an active exception

---------------- test.cc -----------------------------
#include <string>
#include <iostream>
#include <stdexcept>
#include <memory>

class BaseClass
{
public:
        BaseClass()
        { };
        virtual ~BaseClass()
        { };
        virtual std::string const & GetId(void) = 0;
        virtual BaseClass && build(void) = 0;
};

class Derived1 : public BaseClass
{
public:
        Derived1()
        : BaseClass()
        { };

        ~Derived1()
        { }

        std::string const & GetId(void)
        {
                static std::string const & id("Derived1");
                return id;
        }

        Derived1 && build(void)
        {
                return std::move(Derived1());
        }
};

class Derived2 : public BaseClass
{
public:
        Derived2()
        : BaseClass()
        { };

        ~Derived2()
        { }

        std::string const & GetId(void)
        {
                static std::string const & id("Derived2");
                return id;
        }

        Derived2 && build(void)
        {
                return std::move(Derived2());
        }
};

class Factory
{
public:
        static BaseClass && build(std::string const & id)
        {
                if (0 == id.compare("Derived1"))
                {
                        static Derived1 derived1;
                        return std::move(derived1.build());
                }
                else if (0 == id.compare("Derived2"))
                {
                        static Derived2 derived2;
                        return std::move(derived2.build());
                }
                else
                {
                        throw std::runtime_error("invalid type");
                }
        }
};
int main(int argc, char** argv)
{
        try
        {
#if 1
                // this does not work
                BaseClass && baseClass(std::move(Factory::build("Derived1")));
                BaseClass * ptr = &baseClass;
#else
                // this works
                Derived1 && derived1(std::move(Derived1().build()));
                BaseClass * ptr = &derived1;
#endif
                std::cout << "ID = " << ptr->GetId() << std::endl;
        }
        catch (std::exception & e)
        {
                std::cerr << "exception: " << e.what() << std::endl;
        }
        return 0;
}

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