From d572ee54e0e32b52de6b13fcee46fb4bc544b802 Mon Sep 17 00:00:00 2001
From: Menelaos Karavelas <menelaos.karavelas@gmail.com>
Date: Mon, 11 Aug 2014 13:41:27 +0300
Subject: [PATCH] [algorithms][distance] fix unused variable warning when boost
 is compiled in release mode

---
 .../algorithms/detail/distance/geometry_to_geometry_rtree.hpp  | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/include/boost/geometry/algorithms/detail/distance/geometry_to_geometry_rtree.hpp b/include/boost/geometry/algorithms/detail/distance/geometry_to_geometry_rtree.hpp
index 7ebb39466..24df29836 100644
--- a/include/boost/geometry/algorithms/detail/distance/geometry_to_geometry_rtree.hpp
+++ b/include/boost/geometry/algorithms/detail/distance/geometry_to_geometry_rtree.hpp
@@ -17,6 +17,8 @@
 #include <boost/assert.hpp>
 #include <boost/range.hpp>
 
+#include <boost/core/ignore_unused.hpp>
+
 #include <boost/geometry/core/tag.hpp>
 #include <boost/geometry/core/tags.hpp>
 
@@ -92,6 +94,7 @@ private:
                 m_r_tree.query(index::nearest(query_geometry, 1), &t_v);
 
             BOOST_ASSERT( n > 0 );
+            boost::ignore_unused(n);
 
             comparable_return_type cd = dispatch::distance
                 <