Article ID: 166109
Article Last Modified on 7/5/2005
APPLIES TO
- Microsoft Visual C++ 5.0 Enterprise Edition
- Microsoft Visual C++ 5.0 Professional Edition
This article was previously published under Q166109
SYMPTOMS
The compiler generates a compiler error C2248 as follows:
under the following circumstances:
- If a class declares a template function as a friend function, and
- If the template function definition appears after the class definition.
RESOLUTION
Do not declare a template function as a friend of a class.
STATUS
Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article. This problem was corrected in Microsoft Visual C++ version 6.0.
MORE INFORMATION
The following sample demonstrates the problem and the workaround.
Sample Code
/*
Compile option: None
*/
class X;
template <class T> void AFunction(X &x, T &t);
class X
{
private:
int m_n;
public:
template <class T> friend void AFunction(X &x, T &t) ;
};
template <class T> void AFunction(X &x, T &t)
{
x.m_n = t; // C2248 here.
}
int main()
{
X x;
int n;
AFunction(x, n);
return 0 ;
}
NOTE: Defining the template function before the class definition eliminates the compiler error C2248. But the compiler does not generate any code when you call the template function.
Keywords: kbbug kbfix kbvc600fix KB166109
