diff --git a/include/mapnik/feature.hpp b/include/mapnik/feature.hpp
index c232075ad..f340c83d6 100644
--- a/include/mapnik/feature.hpp
+++ b/include/mapnik/feature.hpp
@@ -90,7 +90,7 @@ private:
 using context_type = context<std::map<std::string,std::size_t> >;
 using context_ptr = std::shared_ptr<context_type>;
 
-static const value default_feature_value;
+static const value default_feature_value{};
 
 class MAPNIK_DECL feature_impl : private util::noncopyable
 {