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C ++ How can I get this class structure?

I am trying to understand how to write cross-platform classes, while avoiding the cost of virtual functions and any ugliness in specific versions of classes on the platform. Here is what I have tried.

PlatformIndependantClass.hpp

class PlatformIndependantClass {
    public:
        PlatformIndependantClass();
        std::string GetPlatformName();
    private:
        PlatformIndependantClass* mImplementation;

};

LinuxClass.hpp

#include "PlatformIndependantClass.hpp"
class LinuxClass : public PlatformIndependantClass{
    public:
        std::string GetPlatformName();
};

WindowsClass.hpp

#include "PlatformIndependantClass.hpp"
class WindowsClass : public PlatformIndependantClass {
    public:
        std::string GetPlatformName();
};

PlatformIndependantClass.cpp

#include "PlatformIndependantClass.hpp"
#include "LinuxClass.hpp"
#include "WindowsClass.hpp"
PlatformIndependantClass::PlatformIndependantClass() {
    #ifdef TARGET_LINUX
        mImplementation = new LinuxClass();
    #endif
    #ifdef TARGET_WINDOWS
        mImplementation = new WindowsClass();
    #endif
}
std::string PlatformIndependantClass::GetPlatformName() {
    return mImplementation->GetPlatformName();
}

LinuxClass.cpp

#include "LinuxClass.hpp"
std::string LinuxClass::GetPlatformName() {
    return std::string("This was compiled on linux!");
}

WindowsClass.cpp

#include "WindowsClass.hpp"
std::string WindowsClass::GetPlatformName() {
    return std::string("This was compiled on windows!");
}

main.cpp

#include <iostream>
#include "PlatformIndependantClass.hpp"

using namespace std;

int main()
{
    PlatformIndependantClass* cl = new PlatformIndependantClass();
    cout << "Hello world!" << endl;
    cout << "Operating system name is: " << cl->GetPlatformName() << endl;
    cout << "Bye!" << endl;
    return 0;
}

Now this compiles fine, but I get a segmentation error. I believe this is because platform-specific classes inherit from PlatformIndependantClass, which when built creates an instance of the platform-specific class, so I get infinite recursion. Every time I try, I'm just really confused!

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Object.h:

#include <normal includes>

#if WINDOWS
#include <windows includes>
#endif

#if LINUX
#include <linux includes>
#endif

class Object
{
private:

#if WINDOWS
//Windows Specific Fields...
#endif

#if LINUX
//Linux Specific Fields...
#endif

public:
    //Function that performs platform specific functionality
    void DoPlatformSpecificStuff();

    //Nothing platform specific here
    void DoStuff();      
};

Object.cpp

#include "Object.h"

void Object::DoStuff() { ... }

ObjectWin32.cpp

#if WINDOWS

#include "Object.h"

void Object::DoPlatformSpecificStuff() 
{ 
    //Windows specific stuff... 
}

#endif

ObjectLinux.cpp

#if LINUX

#include "Object.h"

void Object::DoPlatformSpecificStuff() 
{ 
    //Linux specific stuff... 
}

#endif

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PlatformIndependantClass* PlatformIndependantClass::getPlatformIndependantClass() {
    #ifdef TARGET_LINUX
        return new LinuxClass();
    #endif
    #ifdef TARGET_WINDOWS
        return new WindowsClass();
    #endif
}

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PlatformIndependantClass.hpp

#include //portable headers
struct PlatformDependantClass; //defined in Cpp file
class PlatformIndependantClass {
    public:
        PlatformIndependantClass();
        ~PlatformIndependantClass();
        std::string GetPlatformName();
    private:
        std::unique_ptr<PlatformDependantClass> mImplementation; //note, different type

};

LinuxClass.cpp

#ifdef __GNUC__ 
#include //linux headers
#include "PlatformIndependantClass.hpp"
struct PlatformDependantClass { //linux only stuff
     //stuff
};    

PlatformIndependantClass() {
    mImplementation.reset(new PlatformDependantClass );
}
~PlatformIndependantClass() {
}
std::string PlatformIndependantClass::GetPlatformName() {
    return std::string("This was compiled on linux!");
}
#endif //__GNUC__

WindowsClass.cpp

#ifdef _MSC_VER
#include //windows headers
#include "PlatformIndependantClass.hpp"
struct PlatformDependantClass {  //windows only stuff
     //stuff
};    

PlatformIndependantClass() {
    mImplementation.reset(new PlatformDependantClass );
}
~PlatformIndependantClass() {
}
std::string PlatformIndependantClass::GetPlatformName() {
    return std::string("This was compiled on Windows!");
}
#endif //_MSC_VER

. Windows Windows, Linux linux. , void* " " " pimpl" http://en.wikipedia.org/wiki/Opaque_pointer

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