diff --git a/Polyhedron/demo/Polyhedron/Color_map.h b/Polyhedron/demo/Polyhedron/Color_map.h
index 7583e370127..46164c649cb 100644
--- a/Polyhedron/demo/Polyhedron/Color_map.h
+++ b/Polyhedron/demo/Polyhedron/Color_map.h
@@ -16,7 +16,7 @@ inline QColor generate_color(double h, double s_min = 0.35)
 template <typename Output_color_iterator>
 Output_color_iterator
 compute_color_map(QColor base_color,
-                  unsigned nb_of_colors,
+                  std::size_t nb_of_colors,
                   Output_color_iterator out)
 {
   qreal hue = base_color.hueF();
diff --git a/Polyhedron/demo/Polyhedron/Plugins/IO/lcc_io_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/IO/lcc_io_plugin.cpp
index 02d6c0675d1..9bf6a73226c 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/IO/lcc_io_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/IO/lcc_io_plugin.cpp
@@ -63,7 +63,7 @@ public:
   
   
   bool canSave(const CGAL::Three::Scene_item*){return false;}
-  bool save(const CGAL::Three::Scene_item*, QFileInfo fileinfo){
+  bool save(const CGAL::Three::Scene_item*, QFileInfo){
     return false;
   }
   
diff --git a/Three/include/CGAL/Three/Polyhedron_demo_io_plugin_interface.h b/Three/include/CGAL/Three/Polyhedron_demo_io_plugin_interface.h
index e83cb0a2d60..40210f4c6d9 100644
--- a/Three/include/CGAL/Three/Polyhedron_demo_io_plugin_interface.h
+++ b/Three/include/CGAL/Three/Polyhedron_demo_io_plugin_interface.h
@@ -78,7 +78,7 @@ public:
   //! list of available loaders when loading a file, which means it will be the 
   //! first in the list.
   //! @param name is the extension without the dot (e.g. "off" for a .off file)
-  virtual bool isDefaultLoader(const QString& name) const { return false; }
+  virtual bool isDefaultLoader(const QString& name) const { Q_UNUSED(name); return false; }
 };
 }
 }