template and inheritance

[sunnyleekr]

Hi, I am having trouble compiling the simple code below...

//leader.hpp
#ifndef LEADER_HPP
#define LEADER_HPP
class leader
{
public:
leader(){}
virtual ~leader(){}
virtual void hahaha()=0;
virtual void hahahaha()=0;
};
#endif

//soldier.hpp
#ifndef SOLDIER_HPP
#define SOLDIER_HPP
#include "leader.hpp "

template <class T>
class soldier : public leader
{
public:
soldier(){}
virtual ~soldier(){}
virtual void hahaha();
virtual void hahahaha();
};
#endif
//soldier.cpp
#include "soldier.hp p"

template <class T>
void soldier<T>::hah aha()
{

}

template <class T>
void soldier<T>::hah ahaha()
{

}

// test.cpp
#include "leader.hpp "
#include "soldier.hp p"

int main(void)
{
leader *a;

a=new soldier<int>();

delete a;

return 0;
}

when I compile with g++, I get these errors:

g++ -o "test" test.o soldier.o
test.o:(.rodata ._ZTV7soldierIi E[vtable for soldier<int>]+0x10): undefined reference to `soldier<int>:: hahaha()'
test.o:(.rodata ._ZTV7soldierIi E[vtable for soldier<int>]+0x14): undefined reference to `soldier<int>:: hahahaha()'
collect2: ld returned 1 exit status

Is there something wrong with the code??
thanks,
sunny

[Airslash]

I'm going to take a guess here, but you define Soldier as a Template class, but your Constructor doesn't support templates.

[newb16]

You should either explicit instantiate soldier<int> in soldier.cpp or move soldier<T>::hah a() body to header file - compiler doesn't know at the time it compiles soldier.cpp that there will be soldier<int> in main.cpp.