diff --git a/include/boost/preprocessor/facilities/is_empty_variadic.hpp b/include/boost/preprocessor/facilities/is_empty_variadic.hpp
index 653854d..1c1e3d1 100644
--- a/include/boost/preprocessor/facilities/is_empty_variadic.hpp
+++ b/include/boost/preprocessor/facilities/is_empty_variadic.hpp
@@ -1,6 +1,6 @@
 # /* **************************************************************************
 #  *                                                                          *
-#  *     (C) Copyright Edward Diener 2014.
+#  *     (C) Copyright Edward Diener 2014,2019.
 #  *     Distributed under the Boost Software License, Version 1.0. (See
 #  *     accompanying file LICENSE_1_0.txt or copy at
 #  *     http://www.boost.org/LICENSE_1_0.txt)
@@ -64,9 +64,11 @@
     (__VA_ARGS__) \
 /**/
 #define BOOST_PP_IS_EMPTY_ZERO(...) 0
+#if BOOST_PP_VARIADIC_OPT()
 #define BOOST_PP_IS_EMPTY_FUNCTION2(...) \
     __VA_OPT__(0,) 1 \
 /**/
+#endif
 #define BOOST_PP_IS_EMPTY_FUNCTION(...) \
     BOOST_PP_IS_EMPTY_FUNCTION2(__VA_ARGS__) \
 /**/