Why do I keep getting this "undefined reference" error?

Question

driver.cc
#include <iostream>
#include "dynStack.h"

using namespace std;

// class definition
int main()
{
  dynstack<int> c1;


  c1.push(1);

  cout<<"hello";

  return 0;
}


dynStack.h
#include <iostream>

using namespace std;

template <class T>
class dynstack
{
    public:
        dynstack();
        void push(T data);


};


dynStack.cc

#include "dynStack.h"

template <class T>
dynstack<T>::dynstack()
{

}

template <class T>
void dynstack<T>::push(T data)
{


    return data;
}

I'm new to C++. When I run the code, it keeps giving me "undefined reference to 'dynstack::dynstack()' error. I checked include and prototype and couldn't spot the error. Could anyone help me find where I did wrong? Thank you.

`template` classes should have their implementation also in the header file — yizzlez, May 07 '14 at 00:55

score 4 · Accepted Answer · answered May 07 '14 at 00:56

4

Your templated class methods, unless called from within the same .cpp, need to have their implementations in the header, or an inline file included from the header.

answered May 07 '14 at 00:56

Aesthete

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Or an explicit instantiation in the cpp file. – David G May 07 '14 at 00:56

Why do I keep getting this "undefined reference" error?

1 Answers1