DOCUMENT:Q263633  03-MAY-2001  [visualc]
TITLE   :BUG: Error C2946 on Explicit Instantiation of Imported Templates
PRODUCT :Microsoft C Compiler
PROD/VER:winnt:6.0
OPER/SYS:
KEYWORDS:kbtemplate kbCompiler kbCPPonly kbVC600bug kbDSupport

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The information in this article applies to:

 - The C/C++ Compiler (CL.EXE), included with:
    - Microsoft Visual C++, 32-bit Enterprise Edition, version 6.0 
    - Microsoft Visual C++, 32-bit Professional Edition, version 6.0 
    - Microsoft Visual C++, 32-bit Learning Edition, version 6.0 
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SYMPTOMS
========

If you try to perform explicit instantiation of a template class or function
imported from another namespace by means of a using declaration or using
directive, you may receive the following error message:

   Test.cpp(8) : error C2946: explicit instantiation; 'class ?$A@H' is not a
   template-class specialization

RESOLUTION
==========

To work around this problem, qualify the template name with the name of the
namespace in which the template is defined.


STATUS
======

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

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

Steps to Reproduce Behavior
---------------------------

The following sample code demonstrates the bug:

   // Test.cpp
   // Compiler option needed: none
   namespace N {

   template <class T>
   struct A { };
   }

   using namespace N;             // This does not work.
   using N::A;                    // This also does not work.
   template class A<int>;

   // template class N::A<int>;   // This works.

Additional query words: "Compiler Error"

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Keywords          : kbtemplate kbCompiler kbCPPonly kbVC600bug kbDSupport 
Technology        : kbVCsearch kbAudDeveloper kbCVCComp
Version           : winnt:6.0
Issue type        : kbbug
Solution Type     : kbpending

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