Article ID: 117201
Article Last Modified on 7/5/2005
APPLIES TO
- Microsoft C Professional Development System 6.0a
- Microsoft Visual C++ 1.0 Professional Edition
- Microsoft Visual C++ 1.5 Professional Edition
- Microsoft Visual C++ 1.0 Professional Edition
- Microsoft Visual C++ 2.0 Professional Edition
- Microsoft Visual C++ 4.0 Standard Edition
- Microsoft Visual C++ 4.1 Subscription
- Microsoft Visual C++ 4.2 Professional Edition
- Microsoft Visual C++ 5.0 Standard Edition
- Microsoft Visual C++ 6.0 Service Pack 5
- Microsoft Visual C++ .NET 2002 Standard Edition
- Microsoft Visual C++ .NET 2003 Standard Edition
This article was previously published under Q117201
SYMPTOMS
According to ANSI specifications, the sizeof operator returns the unsigned integer size of a particular data type or variable.
When the sizeof operator is used in a comparison with an integer variable, the compiler should, but does not, generate the following warning:
STATUS
Microsoft has confirmed that this is a bug in the Microsoft products that are listed in the "Applies to" section.
MORE INFORMATION
The following sample code can be used to demonstrate the problem. The C4018 warning is produced for the statement in function3, but not for the statements in function1 and function2.
Sample code
/* Compile options needed: /W4 */ int i; unsigned u; int function1(void) { return(i > sizeof(i)); } int function2(void) { return(i > (unsigned) sizeof(i)); } int function3(void) { u = sizeof(i); return(i > u); }
Additional query words: kbVC400bug 6.00 6.00a 6.00ax 7.00 8.00 8.00c 9.00
Keywords: kbbug kbcompiler KB117201