BUG: C2734, C2166: Caused by Template Function with const ref

 Last reviewed: July 14, 1997
Article ID: Q167113
The information in this article applies to:
  • The C/C++ Compiler (CL.EXE) included with: - Microsoft Visual C++, 32-bit Editions, versions 4.2, 4.2b, 5.0

SYMPTOMS

The compiler generates the compiler error C2734 and C2166, when compiling a template function with a const reference of class T as an argument, where class T is a template parameter. 

       C2734:  'identifier' : const object must be initialized if not
               extern
       C2166:  l-value specifies const object

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article. We are researching this bug and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

The following sample demonstrates the problem and the workaround.

Sample Code

    /* Compiler Options: None
    */
    //#define WORKAROUND1 // uncomment this line for workaround1
    //#define WORKAROUND2 // uncomment this line for workaround2

    template <class T>
    T Test (const T& arg1)
   {

    #ifndef WORKAROUND1
        T x ;
      x = arg1;
    #else
       T x = arg1 ; // WORKAROUND 1
    #endif

        return x;
   }

    int main()
   {
    #ifndef WORKAROUND2
        int testValue = Test ( 7 );
   #else
       int testValue = Test <int> ( 7 ); // WORKAROUND 2
   #endif

    return 0;
   }

Keywords : CPPIss CPPLngIss kbtool vcbuglist500
Version : 4.2 4.2b 5.0
Platform : NT WINDOWS
Issue type : kbbug

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.

Last reviewed: July 14, 1997
© 1998 Microsoft Corporation. All rights reserved. Terms of Use.