Q119501: PRB: Error CXX0017 or CXX0034 for typedef

Article: Q119501
Product(s): Microsoft C Compiler
Version(s): 1.0,2.0,2.1,4.0,5.0
Operating System(s): 
Keyword(s): kbDebug kbide
Last Modified: 15-FEB-2002

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The information in this article applies to:

- The Visual Workbench Integrated Debugger, used with:
   - Microsoft Visual C++, 32-bit Editions, versions 1.0, 2.0, 2.1, 4.0 
   - Microsoft Visual C++, 32-bit Enterprise Edition, version 5.0 
   - Microsoft Visual C++, 32-bit Professional Edition, version 5.0 
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SYMPTOMS
========

Declare a structure type and typedef a pointer to the structure type as
follows:

     struct MYSTRUCT {
        int x;
        int y;
     };

     typedef struct MYSTRUCT* PMYSTRUCT;

MYSTRUCT is a structure type and PMYSTRUCT is a typedef for a pointer to
MYSTRUCT. Declare and initialize the following variables:

     struct MYSTRUCT var1 = {0, 0};
     PMYSTRUCT var2 = &var1;

Putting a watch on "(PMYSTRUCT) &var2" produces the following error:

Visual C++ 1.0 and 4.0
----------------------

  CXX0017: Error: symbol 'PMYSTRUCT' not found

Visual C++ 2.x
--------------

  CXX0034: Error: types incompatable with operator

However, putting a watch on "(MYSTRUCT *) &var2" is successful.

CAUSE
=====

The typedef declares a new name for a type, but it does not define a new type.
The typecast attempted in the debugger requires the name of a defined type.

RESOLUTION
==========

Use the defined type in the typecast, rather than using the name declared with
the typedef.

Additional query words:

======================================================================
Keywords          : kbDebug kbide 
Technology        : kbVCsearch kbAudDeveloper
Version           : :1.0,2.0,2.1,4.0,5.0
Issue type        : kbprb

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

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