diff --git a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_slicer.h b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_slicer.h
index 56b4492a42f..92892a87b39 100644
--- a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_slicer.h
+++ b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_slicer.h
@@ -221,7 +221,8 @@ class Polygon_mesh_slicer
     void end_polyline()
     {
       CGAL_assertion(!current_poly.empty());
-      if(is_polyline_cw_oriented(current_poly.begin(), current_poly.end()))
+      if(current_poly.size()>1
+         && is_polyline_cw_oriented(current_poly.begin(), current_poly.end()))
       {
         std::reverse(current_poly.begin(), current_poly.end());
       }