diff --git a/Arrangement_on_surface_2/include/CGAL/Curved_kernel_via_analysis_2/gfx/Curve_renderer_internals.h b/Arrangement_on_surface_2/include/CGAL/Curved_kernel_via_analysis_2/gfx/Curve_renderer_internals.h
index 27907635ae6..111c28a37e2 100644
--- a/Arrangement_on_surface_2/include/CGAL/Curved_kernel_via_analysis_2/gfx/Curve_renderer_internals.h
+++ b/Arrangement_on_surface_2/include/CGAL/Curved_kernel_via_analysis_2/gfx/Curve_renderer_internals.h
@@ -852,8 +852,9 @@ bool get_range_MAA_1(int var, const NT& l_, const NT& r_, const NT& key,
             eval1 = CGAL_SGN(low);
             eval2 = CGAL_SGN(up);
 
-        } else if(d == 0)
+        } else if(d == 0) {
             ;//Gfx_DETAILED_OUT("MAA bounds: sign change\n");
+        }
 
         if(d == 1 && check == 3) {
             first_der = (eval1*eval2 < 0);
diff --git a/Arrangement_on_surface_2/include/CGAL/Curved_kernel_via_analysis_2/gfx/Curve_renderer_traits.h b/Arrangement_on_surface_2/include/CGAL/Curved_kernel_via_analysis_2/gfx/Curve_renderer_traits.h
index bf85bc0a54c..3b22eb350c6 100644
--- a/Arrangement_on_surface_2/include/CGAL/Curved_kernel_via_analysis_2/gfx/Curve_renderer_traits.h
+++ b/Arrangement_on_surface_2/include/CGAL/Curved_kernel_via_analysis_2/gfx/Curve_renderer_traits.h
@@ -241,7 +241,7 @@ struct Curve_renderer_traits_base
         typedef void result_type;
 
         template <class Float>
-        void operator()(const Float& x) const
+        void operator()(const Float& /*x*/) const
         { }
     };
 
@@ -251,7 +251,7 @@ struct Curve_renderer_traits_base
         typedef bool result_type;
 
         template <class Float>
-        bool operator()(const Float& x) const
+        bool operator()(const Float& /*x*/) const
         { return false;/*(CGAL_ABS(x) <= 1e-16)*/; }
     };