Q168373: FIX: C2065 When Default Constructor of a Nested Class Called

Article: Q168373
Product(s): Microsoft C Compiler
Version(s): winnt:5.0
Operating System(s): 
Keyword(s): kbcode kberrmsg kbtool kbVC500bug kbVC600fixkbbuglist
Last Modified: 07-MAY-2001

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The information in this article applies to:

- Microsoft Visual C++, 32-bit Enterprise Edition, version 5.0 
- Microsoft Visual C++, 32-bit Professional Edition, version 5.0 
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SYMPTOMS
========

When the default constructor of a nested class gets called, it causes the C2065
compiler error:

  'identifier' : undeclared identifier

RESOLUTION
==========

Please see the MORE INFORMATION section for a workaround.

STATUS
======

Microsoft has confirmed this to be 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
================

NOTE: Because constructors do not have names, they are never found during name
lookup; however an explicit type conversion using the functional notation causes
a constructor to be called to initialize an object. (This information came from
the C++ Working Paper.)

The following sample code demonstrates the problem and the workaround.

Sample Code
-----------

     /*
     Compile options: None
     */ 

     class Base
     {
     public:

         class Common
         {
         public:
            Common(){};
         };
         class Derived : public Common
         {
         public:
            Derived() {}
            Derived(int n) {}
         };
         Base( const Common &theCommon) {}
     };

     int main(void)
     {
         Base B1(Base::Derived());  //C2065 here

         // Workaround: Comment the above line
         // Uncomment the following lines
         // Base::Derived D ;
         // Base B1(D) ;
         return 0;
     }

Additional query words:

======================================================================
Keywords          : kbcode kberrmsg kbtool kbVC500bug kbVC600fix kbbuglist
Technology        : kbVCsearch kbAudDeveloper kbVC500 kbVC32bitSearch kbVC500Search
Version           : winnt:5.0
Issue type        : kbbug
Solution Type     : kbfix

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