diff -rU4 CMakeA/Modules/CheckFunctionExists.c CMakeB/Modules/CheckFunctionExists.c
--- CMakeA/Modules/CheckFunctionExists.c	2004-04-15 14:22:19.000000000 +0200
+++ CMakeB/Modules/CheckFunctionExists.c	2009-12-30 15:29:07.000000000 +0100
@@ -1,15 +1,18 @@
 #ifdef CHECK_FUNCTION_EXISTS
 
+#ifndef _MSC_VER
 char CHECK_FUNCTION_EXISTS();
+#endif /* _MSC_VER */
+
 #ifdef __CLASSIC_C__
 int main(){
   int ac;
   char*av[];
 #else
 int main(int ac, char*av[]){
 #endif
-  CHECK_FUNCTION_EXISTS();
+  static void * p = (void*) CHECK_FUNCTION_EXISTS;
   if(ac > 1000)
     {
     return *av[0];
     }