Q143083: FIX: C2664 When Array Is Passed as a Parameter to a Function

Article: Q143083
Product(s): Microsoft C Compiler
Version(s): 4.0,4.1,4.2
Operating System(s): 
Keyword(s): kbCompiler kbCPPonly kbVC kbVC500fix
Last Modified: 03-AUG-2001

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The information in this article applies to:

- Microsoft C/C++ Compiler (CL.EXE), used with:
   - *EDITOR Please do not choose this product*Microsoft Visual C++ 32-bit Edition* use 241, 265, 225, versions 4.0, 4.1, 4.2 
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SYMPTOMS
========

The compiler will generate the following error when you pass a multiple
subscript array to a function that expects a const of the same type of array:

  error C2664: 'Func2' : cannot convert parameter 1 from 'int [4][4]' to
  'const int [][4]' (new behavior; please see help)

RESOLUTION
==========

Don't declare the parameter to be 'const' in the function definition.

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++ version 5.0.

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

Sample Code to Demonstrate Problem
----------------------------------

     /* Compile options needed: None
     */ 

     typedef int Matrix1[4];
     typedef int Matrix2[4][4];

     void Func1( const Matrix1 ) {}

     // Remove const in the following statement to work around

     void Func2( const Matrix2 ) {}

     void main()
     {
        Matrix1 a = {1,2,3,4};
        Matrix2 b = {1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4};

        Func1( a );
        Func2( b );   // C2664 here
     }

Additional query words: kbVC400bug

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Keywords          : kbCompiler kbCPPonly kbVC kbVC500fix 
Technology        : kbVCsearch kbAudDeveloper kbCVCComp
Version           : :4.0,4.1,4.2
Issue type        : kbbug
Solution Type     : kbfix

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