FIX: C2466: Using New to Allocate an Array of Size Zero (123811)


The information in this article applies to:

  • Microsoft C/C++ Compiler (CL.EXE)
  • Microsoft C/C++ for MS-DOS 7.0
  • Microsoft Visual C++ 1.0
  • Microsoft Visual C++ 1.5
  • Microsoft Visual C++ 1.51
This article was previously published under Q123811

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
Modification Type:MinorLast Reviewed:7/5/2005
Keywords:kbbug kbCompiler kbCPPonly kbfix KB123811
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