C2385 Error Message When You Use C++ Compiler

This article was previously published under Q323918
This article has been archived. It is offered "as is" and will no longer be updated.
If you compile Visual C++ code with a virtual base constructor, you may receive a C2385 error message.
This problem occurs because of a bug in the C++ compiler in Microsoft Visual Studio .NET.
A supported fix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Apply it only to computers that are experiencing this specific problem. This fix may receive additional testing. Therefore, if you are not severely affected by this problem, Microsoft recommends that you wait for the next Visual Studio .NET service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site:NOTE: In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The typical support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The English version of this fix has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.
   Date           Version       Size             File name        ---------------------------------------------------------   04-Jun-2002    13.0.9503.0   2,105,344 bytes  C1xx.dll   04-Jun-2002    13.0.9503.0   1,757,184 bytes  C2.dll				

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.
More information
To reproduce this problem, compile the following Microsoft Visual C++ .NET code sample in Visual Studio .NET:
#include <stdio.h>class V{public:    V(){ printf("Just testing\n"); }};class A : virtual public V{    /* ... */ };class B : virtual public V{    /* ... */ };class C : public A, public B{    void DoNothing(const V&)    {        ;    }    void VC7_Ambiguity(void)    {        DoNothing(V());    }};int main(void){    C c;    return 0;}				
When you compile this code in Visual Studio .NET, the following output appears in the Output window:
x3.cppx3.cpp(29) : error C2385: ambiguous access of 'V' in 'C'        could be the 'V' in base 'V'        or the 'V' in base 'V'x3.cpp(29) : error C2065: 'V' : undeclared identifier					
Visual C++ Compiler

Article ID: 323918 - Last Review: 10/26/2013 10:15:00 - Revision: 2.0

  • Microsoft Visual C++ .NET 2002 Standard Edition
  • kbnosurvey kbarchive kbbug kbcompiler kbfix kbqfe KB323918