diff --git a/include/mapnik/wkt/wkt_grammar_impl.hpp b/include/mapnik/wkt/wkt_grammar_impl.hpp
index 1b266b814..8cf6f7f0b 100644
--- a/include/mapnik/wkt/wkt_grammar_impl.hpp
+++ b/include/mapnik/wkt/wkt_grammar_impl.hpp
@@ -20,6 +20,7 @@
  *
  *****************************************************************************/
 
+#include <mapnik/config.hpp>
 #include <mapnik/wkt/wkt_grammar.hpp>
 #include <boost/spirit/include/phoenix_core.hpp>
 #include <boost/spirit/include/phoenix_operator.hpp>