Q130547: FIX: C2300 on Explicit Destructor Call in Class Template

Article: Q130547
Product(s): Microsoft C Compiler
Version(s): winnt:
Operating System(s): 
Keyword(s): kbCompiler kbCPPonly kbVCkbbuglist kbfixlist
Last Modified: 25-JUL-2001

-------------------------------------------------------------------------------
The information in this article applies to:

- The C/C++ Compiler (CL.EXE), included with:
   - *EDITOR Please do not choose this product*Microsoft Visual C++ 32-bit Edition* use 241, 265, 225, versions 2.0, 2.1 
-------------------------------------------------------------------------------

SYMPTOMS
========

A class template that makes an explicit call to destructor through a pointer of
the template argument <type_name> generates the following error if the
class template is instantiated with a class type:

  error C2300: 'MyClass' : class does not have a destructor called '~Item'

RESOLUTION
==========

You can work around this problem by using the scope resolution operator (::)
when calling the destructor:

     cpR->Item::~Item();

If the pointer points to an object of a derived class, the objects's virtual
destructor is not called. In this case, it may be nessary to call another
virtual function instead, which then calls the virtual destructor.

Also, this syntax can cause problems if the template is instantiated with a
simple type. See the "References" section of this article for more information.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. This problem was fixed in Microsoft Visual C++,
32-bit Edition, version 4.0.

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

Sample Code to Demonstrate Problem
----------------------------------

  // Compile options needed: none
  template<class Item>
  class classX {
     public:
     void funcX();
     Item* cpR;
  };

  template<class Item>
  void classX<Item>::funcX() {
     cpR->~Item();
  };

  class MyClass {
     public:
     ~MyClass() {};
  };

REFERENCES
==========

For more information, please see the following article in the Microsoft
Knowledge Base:

  Q130546 BUG: C2227 & C2653 on Explicit Destructor Call in Template

Additional query words: 2.00 2.10 9.00 9.10

======================================================================
Keywords          : kbCompiler kbCPPonly kbVC kbbuglist kbfixlist
Technology        : kbVCsearch kbAudDeveloper kbCVCComp
Version           : winnt:
Issue type        : kbbug
Solution Type     : kbfix

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

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