PRB: Debugger Can't Evaluate Cast of Enum to (long*) (121887)



The information in this article applies to:

  • The Visual Workbench Integrated Debugger, when used with:
    • Microsoft Visual C++, 32-bit Enterprise Edition 5.0
    • Microsoft Visual C++, 32-bit Enterprise Edition 6.0
    • Microsoft Visual C++, 32-bit Professional Edition 5.0
    • Microsoft Visual C++, 32-bit Professional Edition 6.0
    • Microsoft Visual C++, 32-bit Learning Edition 6.0
    • Microsoft Visual C++, Macintosh Cross-Development Addon 2.0
    • Microsoft Visual C++, 32-bit Editions 2.0
    • Microsoft Visual C++, 32-bit Editions 2.1
    • Microsoft Visual C++, 32-bit Editions 4.0
    • Microsoft Visual C++, 32-bit Editions 6.0

This article was previously published under Q121887

SYMPTOMS

The Visual Workbench Debugger expression evaluator cannot evaluate the cast of an enumerator to a pointer to a long in C++ code. If you attempt to enter an expression of this type in the debugger's watch window, an error occurs. For example, if you try to watch the enumerator 'a' as shown in the sample code below, the debugger gives this error:
   (long*)a = CXX0019: Error: bad type cast
				
The error occurs even though the cast is legal.

RESOLUTION

If the enumerator is assigned to a pointer to a long at compile time, the debugger can watch the pointer (see the Sample Code section below).

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

The following sample code demonstrates the problem. Entering (long*)a in the Watch window causes error CXX0019.

Sample Code

/* Compile options needed: /Zi /Od test.cpp
*/ 

enum {a=1, b=2, c=3};

void main()
{
   long *ptr;
   ptr = (long*)a;  // Cast works correctly in code.
}
				

Modification Type:MajorLast Reviewed:12/2/2003
Keywords:kbBug kbDebug kbide kbprb KB121887