diff --git a/include/boost/preprocessor/arithmetic/dec.hpp b/include/boost/preprocessor/arithmetic/dec.hpp
index fd3d810..d618a6b 100644
--- a/include/boost/preprocessor/arithmetic/dec.hpp
+++ b/include/boost/preprocessor/arithmetic/dec.hpp
@@ -15,6 +15,8 @@
 # ifndef BOOST_PREPROCESSOR_ARITHMETIC_DEC_HPP
 # define BOOST_PREPROCESSOR_ARITHMETIC_DEC_HPP
 #
+# include <boost/preprocessor/config/config.hpp>
+#
 # /* BOOST_PP_DEC */
 #
 # if ~BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_MWCC()
diff --git a/include/boost/preprocessor/arithmetic/inc.hpp b/include/boost/preprocessor/arithmetic/inc.hpp
index 28e9867..f6677ab 100644
--- a/include/boost/preprocessor/arithmetic/inc.hpp
+++ b/include/boost/preprocessor/arithmetic/inc.hpp
@@ -15,6 +15,8 @@
 # ifndef BOOST_PREPROCESSOR_ARITHMETIC_INC_HPP
 # define BOOST_PREPROCESSOR_ARITHMETIC_INC_HPP
 #
+# include <boost/preprocessor/config/config.hpp>
+#
 # /* BOOST_PP_INC */
 #
 # if ~BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_MWCC()