template function specialization problem

[Bari]

Hi,

When i do the following specializition which commented in the source then
including the header in two cpp files gives me an error:
test3.obj : error LNK2005: "class A<int> * __cdecl makeA<int>(void)"
(??$makeA@H@@YAPAV?$A@H@@XZ) already defined in testSTL.obj

Can you please tell me how i can specialize the template function and still
use the header in multiple cpp files.

Thank you in advance!

Bar



//HEADER
#pragma once

template <class T> class A;
template <class T> A<T>* makeA();

template <typename T>
class A{
private:
A(){}
T _a;
public:
friend A *makeA<>(); //error in g++-3.4, works with g++3.3
};

template <typename T>
A<T>* makeA(){
return new A<T>;
}

//SPECIALIZATION GIVING PROBLEM
template <>
A<int>* makeA(){
return new A<int>;
}
//END PROBLEM SPECIALIZATION

// end header

//CPP

int _tmain(int argc, _TCHAR* argv[])
{
A<int>* a = makeA<int>();
}

 

[Adrian Hawryluk]

Hi,

When i do the following specializition which commented in the source then
including the header in two cpp files gives me an error:
test3.obj : error LNK2005: "class A<int> * __cdecl makeA<int>(void)"
(??$makeA@H@@YAPAV?$A@H@@XZ) already defined in testSTL.obj

Can you please tell me how i can specialize the template function and still
use the header in multiple cpp files.

Thank you in advance!

Bar



//HEADER
#pragma once

template <class T> class A;
template <class T> A<T>* makeA();

template <typename T>
class A{
private:
A(){}
T _a;
public:
friend A *makeA<>(); //error in g++-3.4, works with g++3.3
};

template <typename T>
A<T>* makeA(){
return new A<T>;
}

//SPECIALIZATION GIVING PROBLEM
template <>
A<int>* makeA(){
return new A<int>;
}
//END PROBLEM SPECIALIZATION

// end header

//CPP

int _tmain(int argc, _TCHAR* argv[])
{
A<int>* a = makeA<int>();
}

I tried your code, but I couldn't get it to compile with _tmain(). I'm
not familiar with using TCHAR so, it is probably something that was not
included. Replacing tmain with a regular main signature, it compiled
under g++ 3.4.4 without problem, using it in a header that you gave.

I would try doing a clean then remake your source. I would say it is
probably some phase error. That or a bug in g++ 3.4 .


Adrian

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