c++/5962: g++ compile an link

[onofre at ieav dot cta dot br]

>Number:         5962
>Category:       c++
>Synopsis:       g++ compile an link
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Mar 14 04:36:01 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     onofre@ieav.cta.br
>Release:        gcc version 3.0.4
>Organization:
>Environment:
conectiva linux
2.2.17-14cl #1 qui nov 2 00:24:54 EST 2000 i686 
and mandrake 8.1 2.4.8
>Description:
when I try to compile the code that use template and friend 
function  the link show-me a message 

 g++ -o tcomplex tComplex.cc
tComplex.cc:15: warning: friend declaration `bool operator==(const Complex<T>&,
   const Complex<T>&)' declares a non-template function
tComplex.cc:15: warning: (if this is not what you intended, make sure the
   function template has already been declared and add <> after the function
   name here) -Wno-non-template-friend disables this warning.

IMPORTANTE PARTE
/tmp/ccxZWYam.o: In function `main':
/tmp/ccxZWYam.o(.text+0x4d): undefined reference to `operator==(Complex<float> const&, Complex<float> const&)'
collect2: ld returned 1 exit status  

>How-To-Repeat:
#include <iostream.h>


template <class T> 
   class Complex
{
  public:
  
  T a,b;
  
  Complex(T ,T);
  T Real();
  T Imag();
  
  friend bool operator==(const Complex <T> &,const Complex<T> &);
 
 

  
};
template <class T>
Complex<T>::Complex(T x,T y)
{ 
  a = x;
  b = y;
  }

template <class T>  
T Complex<T>::Real()
  { 
     return a;
     }


template <class T>      
T Complex<T>::Imag()
  { 
     return b;
     }     


template <class T>
 bool operator ==(const Complex<T> &Ca,const Complex<T> &Cb)

  {
    if (Ca.a == Cb.a && Ca.b==Cb.b)
      return true;
    else 
      return false;
}

int main(int argc, char **argv)
{
    
  float a,b;
  a=2.;
  b=3.;
  
  Complex<float> ci(a,b);
  Complex<float> cj(a,b);
  
  if(ci==cj)
    cout<< " same Numbers "<<endl;
  else
    cout << "numbers not the same" << endl;
   
    
  cout<< ci.Real() << " + " << ci.Imag() << endl;   
  }
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
----gnatsweb-attachment----
Content-Type: application/octet-stream; name="tComplex.cc"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="tComplex.cc"

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