Further change to ensure that clang targeting VC++ behaves as the VC++ preprocessor

include/boost/preprocessor/config/config.hpp

@@ -76,7 +76,7 @@
 #    if defined __GCCXML__ || defined __CUDACC__ || defined __PATHSCALE__ || defined __DMC__ || defined __CODEGEARC__ || defined __BORLANDC__ || defined __MWERKS__ || ( defined __SUNPRO_CC && __SUNPRO_CC < 0x5120 ) || defined __HP_aCC && !defined __EDG__ || defined __MRC__ || defined __SC__ || defined __IBMCPP__ || defined __PGI
 #        define BOOST_PP_VARIADICS 0
 #    /* VC++ (C/C++) */
-#    elif defined _MSC_VER && _MSC_VER >= 1400 && (!defined __EDG__ || defined(__INTELLISENSE__))
+#    elif defined _MSC_VER && _MSC_VER >= 1400 && (defined(__clang__) || !defined __EDG__ || defined(__INTELLISENSE__))
 #        define BOOST_PP_VARIADICS 1
 #        undef BOOST_PP_VARIADICS_MSVC
 #        define BOOST_PP_VARIADICS_MSVC 1
@@ -92,7 +92,7 @@
 # elif !BOOST_PP_VARIADICS + 1 < 2
 #    undef BOOST_PP_VARIADICS
 #    define BOOST_PP_VARIADICS 1
-#    if defined _MSC_VER && _MSC_VER >= 1400 && (defined(__INTELLISENSE__) || !(defined __EDG__ || defined __GCCXML__ || defined __CUDACC__ || defined __PATHSCALE__ || defined __DMC__ || defined __CODEGEARC__ || defined __BORLANDC__ || defined __MWERKS__ || defined __SUNPRO_CC || defined __HP_aCC || defined __MRC__ || defined __SC__ || defined __IBMCPP__ || defined __PGI))
+#    if defined _MSC_VER && _MSC_VER >= 1400 && (defined(__clang__) || defined(__INTELLISENSE__) || !(defined __EDG__ || defined __GCCXML__ || defined __CUDACC__ || defined __PATHSCALE__ || defined __DMC__ || defined __CODEGEARC__ || defined __BORLANDC__ || defined __MWERKS__ || defined __SUNPRO_CC || defined __HP_aCC || defined __MRC__ || defined __SC__ || defined __IBMCPP__ || defined __PGI))
 #        undef BOOST_PP_VARIADICS_MSVC
 #        define BOOST_PP_VARIADICS_MSVC 1
 #    endif