diff --git a/AABB_tree/demo/AABB_tree/Scene.h b/AABB_tree/demo/AABB_tree/Scene.h
index 02270e5e0de..e1d009525f5 100644
--- a/AABB_tree/demo/AABB_tree/Scene.h
+++ b/AABB_tree/demo/AABB_tree/Scene.h
@@ -113,9 +113,9 @@ public:
 
     template <class Query>
     void bench_intersection(Facet_tree& tree,const int function,const double duration,
-        char *query_name, const std::vector<Query>& queries, const int nb_queries);
+        const char *query_name, const std::vector<Query>& queries, const int nb_queries);
     void bench_intersections(Facet_tree& tree, const double duration, const int function,
-        char *function_name, const std::vector<Ray>& rays,
+        const char *function_name, const std::vector<Ray>& rays,
         const std::vector<Line>& lines, const std::vector<Plane>& planes,
         const std::vector<Segment>& segments, const int nb_queries);
 
diff --git a/AABB_tree/demo/AABB_tree/benchmarks.cpp b/AABB_tree/demo/AABB_tree/benchmarks.cpp
index a33f7d8fc04..64ba468fc9d 100644
--- a/AABB_tree/demo/AABB_tree/benchmarks.cpp
+++ b/AABB_tree/demo/AABB_tree/benchmarks.cpp
@@ -44,7 +44,7 @@ void Scene::benchmark_intersections(const double duration)
 void Scene::bench_intersections(Facet_tree& tree,
 									              const double duration,
 													      const int function,
-													      char *function_name,
+													      const char *function_name,
 																const std::vector<Ray>& rays,
 																const std::vector<Line>& lines,
 																const std::vector<Plane>& planes,
@@ -225,7 +225,7 @@ template <class Query>
 void Scene::bench_intersection(Facet_tree& tree,
 									const int function,
 									const double duration,
-									char *query_name,
+									const char *query_name,
 									const std::vector<Query>& queries,
 									const int nb_queries)
 {