Article ID: 125495
Article Last Modified on 10/24/2003
APPLIES TO
- Microsoft Visual C++ 2.0 Professional Edition
- Microsoft Visual C++ 2.1
This article was previously published under Q125495
SYMPTOMS
When an enum type is used as a return type of a function template, the compiler generates the following error as the function template is instantiated:
This error happens only when the function template takes arguments that involve a user-defined class template. For more information, please see the "Sample Code" section in this article.
RESOLUTION
To work around the problem, use a typedef to define the enum type, and use it as the return type for the function template.
STATUS
Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.
MORE INFORMATION
The sample code below can be used to demonstrate both the problem and its solution.
Sample Code
/* Compile options needed: none
Use /DFIX to work around the problem
*/
template <class Type>
class TestClass
{
Type t;
};
enum EnumType { E1, E2, E3 };
#ifndef FIX // Used to reproduce the problem
template <class Type>
EnumType EnumReturnDoesntWork( const TestClass<Type> &a )
{
return E1;
}
#else // Used to work around the problem
typedef EnumType MyType;
template <class Type>
MyType EnumReturnDoesntWork( const TestClass<Type> &a )
{
return E1;
}
#endif
void main(void)
{
TestClass<int> a;
EnumReturnDoesntWork( a ); // C2065
}
Additional query words: 2.00 2.10 9.00 9.10 noupdate
Keywords: kbbug kbcpponly kbcompiler KB125495
