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Q216715: FIX: Bad Code Generated in ?: Operator Converting Class Types

Article: Q216715
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 compiling source code containing the ternary operator (?:), if the compiler
converts one of the operands from one class type to another, incorrect code may
be generated or you might receive the following error message:

  fatal error C1001: INTERNAL COMPILER ERROR (compiler file
  'E:\8168\vc98\p2\src\P2\ehexcept.c', line 577)

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

  #include <afx.h>
  class F
  {
  	char m_str[50];
  	CString cstr;
  public:
  	F(char *str)
  	{
  		strcpy(m_str, str);
  		cstr = "CSTRING";
  	}
  	operator CString() 
  	{
  		cstr = m_str;
  		return cstr;
  	}
  };

  void H( const CString & state)
  {
  	F f("test");
  	CString str;
  	str = (state != "off") ? state : 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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