Index: preprocessor/config/config.hpp
===================================================================
--- preprocessor/config/config.hpp	(revision 86692)
+++ preprocessor/config/config.hpp	(working copy)
@@ -83,7 +83,7 @@
 #            define BOOST_PP_VARIADICS 0
 #        endif
 #    /* Wave (C/C++), GCC (C++) */
-#    elif defined __WAVE__ && __WAVE_HAS_VARIADICS__ || defined __GNUC__ && __GXX_EXPERIMENTAL_CXX0X__
+#    elif defined __WAVE__ && __WAVE_HAS_VARIADICS__ || defined __GNUC__ && defined __GXX_EXPERIMENTAL_CXX0X__
 #        define BOOST_PP_VARIADICS 1
 #    /* EDG-based (C/C++), GCC (C), and unknown (C/C++) */
 #    elif !defined __cplusplus && __STDC_VERSION__ >= 199901L || __cplusplus >= 201103L