Q148504: FIX: C2371: Cast to Struct Ptr in Default Arg of Class Member

Article: Q148504
Product(s): Microsoft C Compiler
Version(s): 4.0,4.1,4.2
Operating System(s): 
Keyword(s): kbCompiler kbCPPonly kbVC kbVC500fix
Last Modified: 03-AUG-2001

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The information in this article applies to:

- Microsoft C/C++ Compiler (CL.EXE), used with:
   - *EDITOR Please do not choose this product*Microsoft Visual C++ 32-bit Edition* use 241, 265, 225, versions 4.0, 4.1, 4.2 
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SYMPTOMS
========

When encountering a cast to a structure pointer in the default argument of a
class member function, the Visual C++ compiler generates the following error:

  error C2371: 'MyClass' : redefinition; different basic types

This error does not occur if the function declaration is not a member of a class.

RESOLUTION
==========

If you are casting from an integral literal, remove the cast. For example,
change this:

     MyFunc (struct MyStruct *p = (struct MyStruct*)0);  //C2371 error

to this:

     MyFunc (struct MyStruct *p = 0);                    //no error

If you are casting from a different structure type, remove the struct keyword
from the cast. For example, change this:

     yFunc (struct MyStruct *p = (struct MyStruct*)x);  //C2371 error

to this:

     MyFunc (struct MyStruct *p = (MyStruct*)x);         //no error

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.

Additional query words: kbVC400bug

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Keywords          : kbCompiler kbCPPonly kbVC kbVC500fix 
Technology        : kbVCsearch kbAudDeveloper kbCVCComp
Version           : :4.0,4.1,4.2
Issue type        : kbbug
Solution Type     : kbfix

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