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diff --git a/boost/geometry/algorithms/detail/overlay/needs_self_turns.hpp b/boost/geometry/algorithms/detail/overlay/needs_self_turns.hpp
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+++ b/boost/geometry/algorithms/detail/overlay/needs_self_turns.hpp
@@ -0,0 +1,83 @@
+// Boost.Geometry (aka GGL, Generic Geometry Library)
+
+// Copyright (c) 2017-2017 Barend Gehrels, Amsterdam, the Netherlands.
+
+// Use, modification and distribution is subject to 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)
+
+#ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_OVERLAY_NEEDS_SELF_TURNS_HPP
+#define BOOST_GEOMETRY_ALGORITHMS_DETAIL_OVERLAY_NEEDS_SELF_TURNS_HPP
+
+#include <boost/range.hpp>
+
+#include <boost/geometry/core/tags.hpp>
+#include <boost/geometry/algorithms/num_interior_rings.hpp>
+
+
+namespace boost { namespace geometry
+{
+
+
+#ifndef DOXYGEN_NO_DETAIL
+namespace detail { namespace overlay
+{
+
+template
+<
+    typename Geometry,
+    typename Tag = typename tag<Geometry>::type
+>
+struct needs_self_turns
+{
+};
+
+template <typename Geometry>
+struct needs_self_turns<Geometry, box_tag>
+{
+    static inline bool apply(Geometry const&)
+    {
+        return false;
+    }
+};
+
+template <typename Geometry>
+struct needs_self_turns<Geometry, ring_tag>
+{
+    static inline bool apply(Geometry const&)
+    {
+        return false;
+    }
+};
+
+template <typename Geometry>
+struct needs_self_turns<Geometry, polygon_tag>
+{
+    static inline bool apply(Geometry const& polygon)
+    {
+        return geometry::num_interior_rings(polygon) > 0;
+    }
+};
+
+template <typename Geometry>
+struct needs_self_turns<Geometry, multi_polygon_tag>
+{
+    static inline bool apply(Geometry const& multi)
+    {
+        typedef typename boost::range_value<Geometry>::type polygon_type;
+        std::size_t const n = boost::size(multi);
+        return n > 1 || (n == 1
+             && needs_self_turns<polygon_type>
+                         ::apply(*boost::begin(multi)));
+    }
+};
+
+
+}} // namespace detail::overlay
+#endif // DOXYGEN_NO_DETAIL
+
+
+}} // namespace boost::geometry
+
+
+#endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_OVERLAY_NEEDS_SELF_TURNS_HPP