diff --git a/headers/libs/agg/agg_renderer_outline_aa.h b/headers/libs/agg/agg_renderer_outline_aa.h
index 90ade6cd0c..00e7140220 100644
--- a/headers/libs/agg/agg_renderer_outline_aa.h
+++ b/headers/libs/agg/agg_renderer_outline_aa.h
@@ -1363,7 +1363,7 @@ namespace agg
         typedef typename base_ren_type::color_type color_type;
 
         //---------------------------------------------------------------------
-        renderer_outline_aa(base_ren_type& ren, line_profile_aa& prof) :
+        renderer_outline_aa(base_ren_type& ren, const line_profile_aa& prof) :
             m_ren(&ren),
             m_profile(&prof)
         {
@@ -1534,7 +1534,7 @@ namespace agg
 
     private:
         base_ren_type*   m_ren;
-        line_profile_aa* m_profile; 
+        const line_profile_aa* m_profile; 
         color_type       m_color;
     };