I'm doing a little project in C++ and I've come into some problems regarding virtual functions.

I have a base class with some virtual functions:

#ifndef COLLISIONSHAPE_H_
#define COLLISIONSHAPE_H_


namespace domino
{
class CollisionShape : public DominoItem
{
public:
// CONSTRUCTOR
//-------------------------------------------------

// SETTERS
//-------------------------------------------------

// GETTERS
//-------------------------------------------------

    virtual void GetRadius() = 0;
    virtual void GetPosition() = 0;
    virtual void GetGrowth(CollisionShape* other) = 0;
    virtual void GetSceneNode();

// OTHER
//-------------------------------------------------

    virtual bool overlaps(CollisionShape* shape) = 0;

};
}

#endif /* COLLISIONSHAPE_H_ */

and a SphereShape class which extends CollisionShape and implements the methods above

/* SphereShape.h */

#ifndef SPHERESHAPE_H_
#define SPHERESHAPE_H_

#include "CollisionShape.h"

namespace domino
{
class SphereShape : public CollisionShape
{

public:
// CONSTRUCTOR
//-------------------------------------------------
    SphereShape();
    SphereShape(CollisionShape* shape1, CollisionShape* shape2);

// DESTRUCTOR
//-------------------------------------------------

    ~SphereShape();

// SETTERS
//-------------------------------------------------
    void SetPosition();
    void SetRadius();

// GETTERS
//-------------------------------------------------

    cl_float GetRadius();
    cl_float3 GetPosition();
    SceneNode* GetSceneNode();
    cl_float GetGrowth(CollisionShape* other);

// OTHER
//-------------------------------------------------

    bool overlaps(CollisionShape* shape);
};
}

#endif /* SPHERESHAPE_H_ */

and the .cpp file:

/*SphereShape.cpp*/
 #include "SphereShape.h"

#define max(a,b) (a>b?a:b)

namespace domino
{

// CONSTRUCTOR
//-------------------------------------------------

SphereShape::SphereShape(CollisionShape* shape1, CollisionShape* shape2)
{
}

// DESTRUCTOR
//-------------------------------------------------

SphereShape::~SphereShape()
{
}

// SETTERS
//-------------------------------------------------

void SphereShape::SetPosition()
{
}

void SphereShape::SetRadius()   
{
}

// GETTERS
//-------------------------------------------------

void SphereShape::GetRadius()   
{

}

void SphereShape::GetPosition()   
{  
}


void SphereShape::GetSceneNode()
{
}

void SphereShape::GetGrowth(CollisionShape* other)
{
}

// OTHER
//-------------------------------------------------

bool SphereShape::overlaps(CollisionShape* shape)
{
     return true;
}

}

These classes, along some other get compiled into a shared library.

Building libdomino.so
g++ -m32 -lpthread -ldl -L/usr/X11R6/lib -lglut -lGLU -lGL -shared     -lSDKUtil  -lglut  -lGLEW  -lOpenCL   -L/home/adrian/AMD-APP-SDK-v2.4-lnx32/lib/x86  -L/home/adrian/AMD-APP-SDK-v2.4-lnx32/TempSDKUtil/lib/x86 -L"/home/adrian/AMD-APP-SDK-v2.4-lnx32/lib/x86"   -lSDKUtil  -lglut  -lGLEW  -lOpenCL -o build/debug/x86/libdomino.so build/debug/x86//Material.o build/debug/x86//Body.o build/debug/x86//SphereShape.o build/debug/x86//World.o build/debug/x86//Engine.o build/debug/x86//BVHNode.o

When I compile the code that uses this library I get the following error:

../../../lib/x86//libdomino.so: undefined reference to `vtable for domino::CollisionShape'
../../../lib/x86//libdomino.so: undefined reference to `typeinfo for domino::CollisionShape'

Command used to compile the demo that uses the library:

g++ -o build/debug/x86/startdemo build/debug/x86//CMesh.o build/debug/x86//CSceneNode.o build/debug/x86//OFF.o build/debug/x86//Light.o build/debug/x86//main.o build/debug/x86//Camera.o -m32 -lpthread -ldl -L/usr/X11R6/lib -lglut -lGLU -lGL  -lSDKUtil  -lglut  -lGLEW  -ldomino  -lSDKUtil  -lOpenCL   -L/home/adrian/AMD-APP-SDK-v2.4-lnx32/lib/x86  -L/home/adrian/AMD-APP-SDK-v2.4-lnx32/TempSDKUtil/lib/x86  -L../../../lib/x86/ -L"/home/adrian/AMD-APP-SDK-v2.4-lnx32/lib/x86" 

(the -ldomino flag)

And when I run the demo, I manually tell it about the library:

LD_LIBRARY_PATH=../../lib/x86/:$AMDAPPSDKROOT/lib/x86:$LD_LIBRARY_PATH bin/x86/startdemo 

After reading a bit about virtual functions and virtual tables I understood that virtual tables are handled by the compiler and I shouldn't worry about it, so I'm a little bit confused on how to handle this issue.

I'm using gcc version 4.6.0 20110530 (Red Hat 4.6.0-9) (GCC)

Later edit: I'm really sorry, but I wrote the code by hand directly here. I have defined the return types in the code. I apologize to the 2 people that answered below.

I have to mention that I am a beginner at using more complex project layouts in C++.By this I mean more complex makefiles, shared libraries, stuff like that.