Q164947: FIX: Nested Macros Cause Errors C2065 and C2064

Article: Q164947
Product(s): Microsoft C Compiler
Version(s): winnt:4.0,4.1
Operating System(s): 
Keyword(s): kbCodeGen kbCompiler
Last Modified: 04-AUG-2001

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The information in this article applies to:

- The C/C++ Compiler (CL.EXE), included with:
   - Microsoft Visual C++, 32-bit Editions, versions 4.0, 4.1 
-------------------------------------------------------------------------------

SYMPTOMS
========

A nested macro may cause errors similar to the following:

  error C2065: 'MACRO_B' : undeclared identifier

  error C2064: term does not evaluate to a function

  error C2143: syntax error : missing ';' before '}'

CAUSE
=====

The second macro is not being expanded correctly. A preprocessed file for the
following sample shows that MACRO_B is not expanded:

        { MACRO_B ("Hello world.\n") };

It should expand to:

        { { printf("Hello world.\n"); } };

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++ 32-bit Edition,
versions 4.2.

MORE INFORMATION
================

Sample Code
-----------

        /* Compile options needed: none
        */ 

        #include <stdio.h>

        #define MACRO_A(A)      { MACRO_B A }
        #define MACRO_B(A)      { printf(A); }

        void main()
        {
            MACRO_A(("Hello world.\n"));
        }

Additional query words: kbVC420bug kbVC400bug

======================================================================
Keywords          : kbCodeGen kbCompiler 
Technology        : kbVCsearch kbAudDeveloper kbCVCComp
Version           : winnt:4.0,4.1
Issue type        : kbbug
Solution Type     : kbfix

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

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