Q139871: FIX: Error C2371 on Struct Typedef that Does Not Have a Tag

Article: Q139871
Product(s): Microsoft C Compiler
Version(s): 2.0,2.1,2.2,4.0,4.1,4.2
Operating System(s): 
Keyword(s): kbLangCPP kbVC kbVC400bug kbVC500fix
Last Modified: 31-JUL-2001

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The information in this article applies to:

- Microsoft Visual C++, versions 2.0, 2.1, 2.2, 4.0, 4.1, 4.2, used with:
   - the operating system: Microsoft Windows NT 
-------------------------------------------------------------------------------

SYMPTOMS
========

If you have a typedef for a structure that doesn't have a tag, you may receive
the following error when you compile the code:

  Error C2371: '<typedef tag>' : redefinition; different basic types

RESOLUTION
==========

Include a tag for the structure.

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 C++ version 5.0.

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

Sample Code to Reproduce Problem
--------------------------------

     /* Compile options needed: none
     */ 

     class A
     {
       public:
         const A& operator=(const A&);
     };

     typedef struct  // add tag here
     {
        A a;
     } B;

     B t1, t2;

     void f()
     {
       t2 = t1;
     }

     void main()
     {
        f();
     }

Additional query words:

======================================================================
Keywords          : kbLangCPP kbVC kbVC400bug kbVC500fix 
Technology        : kbVCsearch kbAudDeveloper
Version           : :2.0,2.1,2.2,4.0,4.1,4.2
Issue type        : kbbug
Solution Type     : kbfix

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

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