diff --git a/CGAL_ImageIO/include/CGAL/IO/read_vtk_image_data.h b/CGAL_ImageIO/include/CGAL/IO/read_vtk_image_data.h
index a7a4d9596b2..e02f4f91eb5 100644
--- a/CGAL_ImageIO/include/CGAL/IO/read_vtk_image_data.h
+++ b/CGAL_ImageIO/include/CGAL/IO/read_vtk_image_data.h
@@ -88,7 +88,7 @@ read_vtk_image_data(vtkImageData* vtk_image, Image_3::Own owning = Image_3::OWN_
   // If there is more than a scalar per point, vtk_image->data is not immediately
   // interpretable in Image_3->data
   CGAL_assertion(owning == Image_3::OWN_THE_DATA || cn == 1);
-  CGAL_assertion(vtk_image->GetPointData()->GetScalars()->GetNumberOfTuples() == image->xdim*image->ydim*image->zdim);
+  CGAL_assertion(vtk_image->GetPointData()->GetScalars()->GetNumberOfTuples() == static_cast<vtkIdType>(image->xdim*image->ydim*image->zdim));
 
   if(owning == Image_3::OWN_THE_DATA) {
     std::size_t dims_n = image->xdim*image->ydim*image->zdim;
diff --git a/Isosurfacing_3/include/CGAL/Isosurfacing_3/edge_intersection_oracles_3.h b/Isosurfacing_3/include/CGAL/Isosurfacing_3/edge_intersection_oracles_3.h
index 5d84ad95408..5bbbc616cb9 100644
--- a/Isosurfacing_3/include/CGAL/Isosurfacing_3/edge_intersection_oracles_3.h
+++ b/Isosurfacing_3/include/CGAL/Isosurfacing_3/edge_intersection_oracles_3.h
@@ -188,10 +188,10 @@ struct Linear_interpolation_edge_intersection
 struct Ray_marching_edge_intersection
 {
   template <typename Domain>
-  bool operator()(const typename Domain::edge_descriptor& e,
-                  const Domain& domain,
-                  const typename Domain::Geom_traits::FT isovalue,
-                  typename Domain::Geom_traits::Point_3& p) const
+  bool operator()(const typename Domain::edge_descriptor& /* e */,
+                  const Domain& /* domain */,
+                  const typename Domain::Geom_traits::FT /* isovalue */,
+                  typename Domain::Geom_traits::Point_3& /* p */) const
   {
     // @todo this is for the case where we know domain.value is an SDF
     // then we can do better than a dichotomy
diff --git a/Isosurfacing_3/include/CGAL/Isosurfacing_3/internal/partition_traits_Cartesian_grid.h b/Isosurfacing_3/include/CGAL/Isosurfacing_3/internal/partition_traits_Cartesian_grid.h
index 871052f8f4b..49239cebf4f 100644
--- a/Isosurfacing_3/include/CGAL/Isosurfacing_3/internal/partition_traits_Cartesian_grid.h
+++ b/Isosurfacing_3/include/CGAL/Isosurfacing_3/internal/partition_traits_Cartesian_grid.h
@@ -161,9 +161,9 @@ struct partition_traits<Cartesian_grid_3<GeomTraits, MemoryPolicy> >
         for(std::size_t k=0; k<g.zdim()-1; ++k)
         {
           // all three edges starting at vertex (i, j, k)
-          f({i, j, k, 0});
-          f({i, j, k, 1});
-          f({i, j, k, 2});
+          f({{i, j, k, 0}});
+          f({{i, j, k, 1}});
+          f({{i, j, k, 2}});
         }
       }
     }
@@ -178,7 +178,7 @@ struct partition_traits<Cartesian_grid_3<GeomTraits, MemoryPolicy> >
     for(std::size_t i=0; i<g.xdim()-1; ++i)
       for(std::size_t j=0; j<g.ydim()-1; ++j)
         for(std::size_t k=0; k<g.zdim()-1; ++k)
-          f({i, j, k});
+          f({{i, j, k}});
   }
 
   #ifdef CGAL_LINKED_WITH_TBB
@@ -236,11 +236,8 @@ struct partition_traits<Cartesian_grid_3<GeomTraits, MemoryPolicy> >
                             const Grid& g,
                             const CGAL::Parallel_tag)
   {
-    const std::size_t sj = g.ydim();
-    const std::size_t sk = g.zdim();
-
     // for now only parallelize outer loop
-    auto iterator = [&f, sj, sk](const tbb::blocked_range3d<std::size_t>& r)
+    auto iterator = [&f](const tbb::blocked_range3d<std::size_t>& r)
     {
       const std::size_t i_begin = r.pages().begin();
       const std::size_t i_end = r.pages().end();