move decl of realmain() out of #ifdef
diff --git a/Modules/config.c.in b/Modules/config.c.in
index d625067..327b9a0 100644
--- a/Modules/config.c.in
+++ b/Modules/config.c.in
@@ -62,8 +62,9 @@
 static char **orig_argv;
 static int  orig_argc;
 
+extern int realmain PROTO((int, char**));
+
 #if defined(__cplusplus)
-int realmain(int, char**);
 main(int argc, char **argv)
 #else
 main(argc, argv)