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Q216722: FIX: C2440 Using Function Pointer As Class Template Argument

Article: Q216722
Product(s): Microsoft C Compiler
Version(s): winnt:6.0
Operating System(s): 
Keyword(s): kbservicepack kbCompiler kbCPPonly kbVC600bug kbVC600fix kbVS600sp2 kbVS600SP1 kbVS600s
Last Modified: 07-MAY-2001

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The information in this article applies to:

- 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 
-------------------------------------------------------------------------------

SYMPTOMS
========

When initiating a class template that uses a function pointer as a template
parameter, you may receive the following error:

  error C2440: ''specialization'' : cannot convert from 'function prototype' to
  ''int (__cdecl *)( *)''

STATUS
======

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

This bug was corrected in Visual Studio 6.0 Service Pack 3. For more information
about Visual Studio service packs, please see the following articles in the
Microsoft Knowledge Base:

  Q194022 INFO: Visual Studio 6.0 Service Packs, What, Where, Why

  Q194295 HOWTO: Tell That Visual Studio 6.0 Service Packs Are Installed

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

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

Use the following sample code to recreate the error message.

  template < class T, int (*pfn)(T *)>
  class F
  {
  public:
  	int Test( T *pb ) {
      	return (*pfn)(	pb );
  	}
  };

  int Bar( int *pb ) {
  	return *pb;
  }

  F<int,&Bar> f;

Additional query words:

======================================================================
Keywords          : kbservicepack kbCompiler kbCPPonly kbVC600bug kbVC600fix kbVS600sp2 kbVS600SP1 kbVS600sp3fix 
Technology        : kbVCsearch kbAudDeveloper kbVC600 kbVC32bitSearch
Version           : winnt:6.0
Issue type        : kbbug
Solution Type     : kbfix

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

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