Microsoft KB Archive/228455

= PRB: Missing /c Compiler Option Causes LNK1561 Linker Error =

Article ID: 228455

Article Last Modified on 11/18/2003

-

APPLIES TO


 * Microsoft Visual C++ 6.0 Enterprise Edition
 * Microsoft Visual C++ 6.0 Professional Edition
 * Microsoft Visual C++ 6.0 Standard Edition

-



This article was previously published under Q228455



SYMPTOMS
When compiling a multiple source file project that creates a pre-compiled header file inside the Visual C++ Integrated Development Environment (IDE), the following error can occur:

Compiling...

StdAfx.cpp

LINK : fatal error LNK1561: entry point must be defined

Error executing cl.exe.

NOTE: The linker error is generated during the compiler phase of the build.



CAUSE
The /c compiler option is missing from the build settings.



RESOLUTION
Add /c to the compiler options. To do this, you must edit the compiler options in the Project Options box in the C/C++ tab under Project Settings.

NOTE: This box is only editable if the whole project is selected in the tree control on the Project Settings.



STATUS
This behavior is by design.



MORE INFORMATION
By default, the Visual C/C++ compiler attempts to compile and link in a single step. The /c (Compile without Linking) option is used to tell the compiler to compile only. Since Visual C++ compiles and links in separate steps, then /c is required for all Visual C++ builds.

To reproduce the error, create a default MFC project and remove the /c option from the Project Settings by editing the compiler options in the Project Options box in the C/C++ tab under Project Settings.

