Q167321: FIX: Wrong Namespace Member Selected for Qualified ID

Article: Q167321
Product(s): Microsoft C Compiler
Version(s): 5.0,6.0
Operating System(s): 
Keyword(s): kbcode kbCompiler kbCPPonly kbLangCPP kbVC kbVC500bug kbVC600bug kbNoUpdatekbbuglist
Last Modified: 10-FEB-2002

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The information in this article applies to:

- Microsoft Visual C++, 32-bit Enterprise Edition, versions 5.0, 6.0 
- Microsoft Visual C++, 32-bit Professional Edition, versions 5.0, 6.0 
- Microsoft Visual C++, 32-bit Learning Edition, version 6.0 
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SYMPTOMS
========

The wrong member function is called if you:

- define a class with the same name, in different scopes;

- create a temporary object, as shown in the sample, of that class type;

- call a member function of that class.

See the MORE INFORMATION section for a sample that demonstrates the problem and
the workaround.

RESOLUTION
==========

Do not create a temporary object. Instead create a local object, and then call
the member functions through the local object.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article.

This problem was corrected in Microsoft Visual C++ .NET.

MORE INFORMATION
================

The following sample demonstrates the problem and the workaround.

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

  /*
  Compile Options: /GX
  */ 
  # include <iostream>
  using namespace std ;

  struct CMyClass
  {
     virtual void DoSomething()
     {
        cout << "::CMyClass::DoSomething()\n";
     }
  };

  namespace MyNameSpace
  {
     struct CMyClass
     {
        virtual void DoSomething()
        {
           cout << "MyNameSpace::CMyClass::DoSomething()\n";
        }
     };
  }

  int main()
  {
     MyNameSpace::CMyClass().DoSomething() ;
     // Workaround: Comment the line above,
     // Uncomment the following lines
     // MyNameSpace::CMyClass C1 ;
     // C1.DoSomething();
     return 0;
  }

Additional query words: namespace

======================================================================
Keywords          : kbcode kbCompiler kbCPPonly kbLangCPP kbVC kbVC500bug kbVC600bug kbNoUpdate kbbuglist
Technology        : kbVCsearch kbAudDeveloper kbVC500 kbVC600 kbVC32bitSearch kbVC500Search
Version           : :5.0,6.0
Issue type        : kbbug
Solution Type     : kbfix

=============================================================================

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