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Q123811: FIX: C2466: Using New to Allocate an Array of Size Zero

Article: Q123811
Product(s): Microsoft C Compiler
Version(s): 
Operating System(s): 
Keyword(s): kbCompiler kbCPPonly kbVCkbbuglist kbfixlist
Last Modified: 30-JUL-2001

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The information in this article applies to:

- 
   - Microsoft C/C++ Compiler (CL.EXE) 
   - Microsoft C/C++ for MS-DOS, version 7.0 
   - Microsoft Visual C++, versions 1.0, 1.5, 1.51 
   - *EDITOR Please do not choose this product*Microsoft Visual C++ 32-bit Edition* use 241, 265, 225, version 1.0 
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SYMPTOMS
========

If a constant expression that evaluates to zero is used to allocate an array,
the following error occurs:

  error C2466: cannot allocate an array of constant size 0

RESOLUTION
==========

To work around the problem, use a variable that is initialized to zero in place
of the constant when allocating the array.

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,
version 2.0.

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

The operator new() can be called with the argument zero. A distinct (non- null)
pointer to an object will be returned (see Section 5.3.3 of the ARM - M.A.Ellis,
B.Stroustrup). This is the behavior observed with Visual C++ version 2.0.

The following sample code can be used to demonstrate the problem.

Sample Code to Reproduce Problem
--------------------------------

  /* Compile options needed: none
  */ 

  char * p = new char[0];  // Causes C2466

Additional query words: 1.00 1.50 7.00 8.00 8.00c

======================================================================
Keywords          : kbCompiler kbCPPonly kbVC kbbuglist kbfixlist
Issue type        : kbbug
Solution Type     : kbfix

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

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