Q133070: PRB: C2059 Error Using extern "C" in .C Source Files

Article: Q133070
Product(s): Microsoft C Compiler
Version(s): 2.0,2.1,2.2,4.0,5.0
Operating System(s): 
Keyword(s): kberrmsg kbLangC kbLangCPP kbVC200 kbVC210 kbVC220 kbVC400 kbVC410 kbVC500 kbVC600
Last Modified: 11-JUN-2002

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The information in this article applies to:

- The C/C++ Compiler (CL.EXE), included with:
   - Microsoft Visual C++, 32-bit Editions, versions 2.0, 2.1, 2.2, 4.0 
   - Microsoft Visual C++, 32-bit Enterprise Edition, version 5.0 
   - Microsoft Visual C++, 32-bit Professional Edition, version 5.0 
   - Microsoft Visual C++.NET (2002) 
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SUMMARY
=======

Use of "extern "C"" in source files that have a .C extension causes error C2059,
and results in this error message:

  error C2059:syntax error:'string'

CAUSE
=====

In the C language, the string-literal "C" is not recognized. It is used in C++
to prevent name decoration.

RESOLUTION
==========

Remove the string-literal "C" in extern declarations, or use the following in
the function declaration:

  #ifdef __cplusplus
     extern "C"
  #endif

STATUS
======

This behavior is by design.

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

Sample Code to Reproduce Behavior
---------------------------------

  /* Compile options needed: None
     The following program reproduces the behavior if the source
     file has .C extension
  */ 

  #include <windows.h>

  extern "C" _declspec(dllexport) BOOL WINAPI function1(void);

  BOOL WINAPI DllMain ( HINSTANCE hInst, DWORD dwReason,
                          LPVOID lpReserved)
  {
     // Other required code goes here.
     return TRUE;
  }

Additional query words: 9.0 9.00 9.1 9.10

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Keywords          : kberrmsg kbLangC kbLangCPP kbVC200 kbVC210 kbVC220 kbVC400 kbVC410 kbVC500 kbVC600 
Technology        : kbVCsearch kbAudDeveloper kbCVCComp
Version           : :2.0,2.1,2.2,4.0,5.0
Issue type        : kbprb

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