diff --git a/src/ifcgeom/AbstractKernel.h b/src/ifcgeom/AbstractKernel.h
index 7f64b2bc25..c8f12cc2b2 100644
--- a/src/ifcgeom/AbstractKernel.h
+++ b/src/ifcgeom/AbstractKernel.h
@@ -91,7 +91,7 @@ namespace {
 
 	template <>
 	struct dispatch_conversion<ifcopenshell::geometry::taxonomy::type_by_kind::max> {
-		static bool dispatch(ifcopenshell::geometry::kernels::AbstractKernel*, ifcopenshell::geometry::taxonomy::kinds item_kind, const ifcopenshell::geometry::taxonomy::ptr item, IfcGeom::ConversionResults&) {
+		static bool dispatch(ifcopenshell::geometry::kernels::AbstractKernel*, ifcopenshell::geometry::taxonomy::kinds, const ifcopenshell::geometry::taxonomy::ptr item, IfcGeom::ConversionResults&) {
 			Logger::Error("No conversion for " + std::to_string(item->kind()));
 			return false;
 		}
diff --git a/src/ifcgeom/IfcGeomRepresentation.h b/src/ifcgeom/IfcGeomRepresentation.h
index 5cfd3d0bc2..b0c5bbb12e 100644
--- a/src/ifcgeom/IfcGeomRepresentation.h
+++ b/src/ifcgeom/IfcGeomRepresentation.h
@@ -70,7 +70,7 @@ namespace IfcGeom {
 			bool calculate_surface_area(double&) const;
 			bool calculate_projected_surface_area(const ifcopenshell::geometry::taxonomy::matrix4& ax, double& along_x, double& along_y, double& along_z) const;
 
-			int size() const { return shapes_.size(); }
+			int size() const { return (int) shapes_.size(); }
 			const IfcGeom::ConversionResultShape* item(int i) const;
 			int item_id(int i) const;
 		};
diff --git a/src/ifcgeom/Iterator.h b/src/ifcgeom/Iterator.h
index d348f24dfc..ee017ea787 100644
--- a/src/ifcgeom/Iterator.h
+++ b/src/ifcgeom/Iterator.h
@@ -231,7 +231,7 @@ namespace IfcGeom {
 
 				task_result_index_ = 0;
 				done = 0;
-				total = tasks_.size();
+				total = (int) tasks_.size();
 
 				if (num_threads_ != 1) {
 					init_future_ = std::async(std::launch::async, [this]() { process_concurrently(); });
diff --git a/src/ifcgeom/kernels/cgal/CgalConversionResult.cpp b/src/ifcgeom/kernels/cgal/CgalConversionResult.cpp
index 0947129b57..1cb9b301c7 100644
--- a/src/ifcgeom/kernels/cgal/CgalConversionResult.cpp
+++ b/src/ifcgeom/kernels/cgal/CgalConversionResult.cpp
@@ -168,7 +168,7 @@ void ifcopenshell::geometry::CgalShape::Triangulate(ifcopenshell::geometry::Sett
 				vidx = it->second;
 			}
 
-			vertexidx[i++] = vidx;
+			vertexidx[i++] = (int) vidx;
 
 			++num_vertices;
 			++current_halfedge;
@@ -216,7 +216,7 @@ double ifcopenshell::geometry::CgalShape::bounding_box(void *& b) const {
 }
 
 int ifcopenshell::geometry::CgalShape::num_vertices() const {
-	return static_cast<cgal_shape_t>(*this).size_of_vertices();
+	return (int) static_cast<cgal_shape_t>(*this).size_of_vertices();
 }
 
 void ifcopenshell::geometry::CgalShape::set_box(void * b) {
@@ -228,14 +228,14 @@ void ifcopenshell::geometry::CgalShape::set_box(void * b) {
 
 int ifcopenshell::geometry::CgalShape::surface_genus() const {
 	to_poly();
-	int nv = shape_->size_of_vertices();
-	int ne = shape_->size_of_halfedges() / 2;
-	int nf = shape_->size_of_facets();
+	auto nv = shape_->size_of_vertices();
+	auto ne = shape_->size_of_halfedges() / 2;
+	auto nf = shape_->size_of_facets();
 
-	const int euler = nv - ne + nf;
-	const int genus = (2 - euler) / 2;
+	auto euler = nv - ne + nf;
+	auto genus = (2 - euler) / 2;
 
-	return genus;
+	return (int) genus;
 }
 
 bool ifcopenshell::geometry::CgalShape::is_manifold() const {
@@ -247,18 +247,18 @@ bool ifcopenshell::geometry::CgalShape::is_manifold() const {
 int ifcopenshell::geometry::CgalShape::num_edges() const
 {
 	to_poly();
-	return shape_->size_of_halfedges() / 2;
+	return (int) shape_->size_of_halfedges() / 2;
 }
 
 int ifcopenshell::geometry::CgalShape::num_faces() const
 {
 #ifndef IFOPSH_SIMPLE_KERNEL
 	if (nef_) {
-		return nef_->number_of_facets();
+		return (int) nef_->number_of_facets();
 	} else
 #endif
 	if (shape_) {
-		return shape_->size_of_facets();
+		return (int) shape_->size_of_facets();
 	} else {
 		return 0;
 	}
@@ -537,11 +537,11 @@ ConversionResultShape* ifcopenshell::geometry::CgalShape::moved(ifcopenshell::ge
 	return new CgalShape(s, convex_tag_);
 }
 
-void ifcopenshell::geometry::CgalShape::map(OpaqueCoordinate<4>& from, OpaqueCoordinate<4>& to) {
+void ifcopenshell::geometry::CgalShape::map(OpaqueCoordinate<4>&, OpaqueCoordinate<4>&) {
 	throw std::runtime_error("Not implemented");
 }
 
-void ifcopenshell::geometry::CgalShape::map(const std::vector<OpaqueCoordinate<4>>& from, const std::vector<OpaqueCoordinate<4>>& to) {
+void ifcopenshell::geometry::CgalShape::map(const std::vector<OpaqueCoordinate<4>>&, const std::vector<OpaqueCoordinate<4>>&) {
 	throw std::runtime_error("Not implemented");
 }
 
diff --git a/src/ifcgeom/kernels/cgal/nef_to_halfspace_tree.h b/src/ifcgeom/kernels/cgal/nef_to_halfspace_tree.h
index 30765969ce..fa410a84f9 100644
--- a/src/ifcgeom/kernels/cgal/nef_to_halfspace_tree.h
+++ b/src/ifcgeom/kernels/cgal/nef_to_halfspace_tree.h
@@ -252,12 +252,13 @@ enum tree_type { TT_NARY_BRANCH, TT_PLANE };
 template <typename Kernel>
 class halfspace_tree {
 public:
-	virtual CGAL::Nef_polyhedron_3<Kernel> evaluate(int level = 0) const = 0;
+	virtual CGAL::Nef_polyhedron_3<Kernel> evaluate() const = 0;
 	virtual void accumulate(std::list<typename Kernel::Plane_3>&) const = 0;
 	virtual std::unique_ptr<halfspace_tree> map(const plane_map<Kernel>&) const = 0;
 	virtual std::string dump(int level = 0) const = 0;
 	virtual tree_type kind() const = 0;
 	virtual void merge(CGAL::Nef_polyhedron_3<Kernel>&) const = 0;
+	virtual ~halfspace_tree() {}
 };
 
 // Halfspace tree component as n-ary operands
@@ -291,18 +292,18 @@ public:
 		ss << std::string(level * 2, ' ') << ")" << std::endl;
 		return ss.str();
 	}
-	virtual CGAL::Nef_polyhedron_3<Kernel> evaluate(int level) const {
+	virtual CGAL::Nef_polyhedron_3<Kernel> evaluate() const {
 		CGAL::Nef_polyhedron_3<Kernel> result;
 
 		if (operation_ == OP_SUBTRACTION) {
 			if (operands_.size() != 2) {
 				throw std::runtime_error("");
 			}
-			result = operands_.front()->evaluate(level + 1) - operands_.back()->evaluate(level + 1);
+			result = operands_.front()->evaluate() - operands_.back()->evaluate();
 		} else if (operation_ == OP_UNION) {
 			CGAL::Nef_nary_union_3<CGAL::Nef_polyhedron_3<Kernel>> builder;
 			for (auto& op : operands_) {
-				builder.add_polyhedron(op->evaluate(level + 1));
+				builder.add_polyhedron(op->evaluate());
 			}
 			result = builder.get_union();
 		} else if (operation_ == OP_INTERSECTION) {
@@ -320,7 +321,7 @@ public:
 				bool first = true;
 				for (auto& op : operands_) {
 					if (first) {
-						result = op->evaluate(level + 1);
+						result = op->evaluate();
 						first = false;
 					} else {
 						op->merge(result);
@@ -329,7 +330,7 @@ public:
 			} else {
 				CGAL::Nef_nary_intersection_3<CGAL::Nef_polyhedron_3<Kernel>> builder;
 				for (auto& op : operands_) {
-					builder.add_polyhedron(op->evaluate(level + 1));
+					builder.add_polyhedron(op->evaluate());
 				}
 				result = builder.get_intersection();
 			}
@@ -339,11 +340,11 @@ public:
 			bool first = true;
 			for (auto& op : operands_) {
 				if (first) {
-					r = op->evaluate(level + 1);
+					r = op->evaluate();
 					first = false;
 					continue;
 				}
-				r = r * op->evaluate(level + 1);
+				r = r * op->evaluate();
 			}
 			return r;
 			*/
@@ -451,7 +452,7 @@ public:
 		ss << std::string(level * 2, ' ') << "p " << std::setprecision(15) << plane_ << std::endl;
 		return ss.str();
 	}
-	virtual CGAL::Nef_polyhedron_3<Kernel> evaluate(int level) const {
+	virtual CGAL::Nef_polyhedron_3<Kernel> evaluate() const {
 		if constexpr(CGAL::Is_extended_kernel<Kernel>::value_type::value) {
 			throw std::runtime_error("Not implemented yet");
 			// typename Kernel::Plane_3 plane(plane_.a().exact(), plane_.b().exact(), plane_.c().exact(), plane_.d().exact());
diff --git a/src/ifcgeom/kernels/opencascade/OpenCascadeConversionResult.cpp b/src/ifcgeom/kernels/opencascade/OpenCascadeConversionResult.cpp
index 0bedee7355..8f3193469b 100644
--- a/src/ifcgeom/kernels/opencascade/OpenCascadeConversionResult.cpp
+++ b/src/ifcgeom/kernels/opencascade/OpenCascadeConversionResult.cpp
@@ -430,10 +430,10 @@ ConversionResultShape* ifcopenshell::geometry::OpenCascadeShape::moved(ifcopensh
 	return new OpenCascadeShape(IfcGeom::util::apply_transformation(shape_, *t));
 }
 
-void ifcopenshell::geometry::OpenCascadeShape::map(OpaqueCoordinate<4>& from, OpaqueCoordinate<4>& to) {
+void ifcopenshell::geometry::OpenCascadeShape::map(OpaqueCoordinate<4>&, OpaqueCoordinate<4>&) {
 	throw std::runtime_error("Not implemented");
 }
 
-void ifcopenshell::geometry::OpenCascadeShape::map(const std::vector<OpaqueCoordinate<4>>& from, const std::vector<OpaqueCoordinate<4>>& to) {
+void ifcopenshell::geometry::OpenCascadeShape::map(const std::vector<OpaqueCoordinate<4>>&, const std::vector<OpaqueCoordinate<4>>&) {
 	throw std::runtime_error("Not implemented");
 }
diff --git a/src/ifcgeom/taxonomy.h b/src/ifcgeom/taxonomy.h
index 7a5d7f1d32..6d130e9953 100644
--- a/src/ifcgeom/taxonomy.h
+++ b/src/ifcgeom/taxonomy.h
@@ -289,7 +289,7 @@ typedef item const* ptr;
 							boost::hash_combine(h, std::hash<typename T::Scalar>()(elem));
 						}
 					}
-					return h;
+					return (uint32_t) h;
 				}
 			};
 
@@ -741,7 +741,8 @@ typedef item const* ptr;
 					for (auto& c : children) {
 						boost::hash_combine(h, c->hash());
 					}
-					return h;
+					// @todo should we really use uint32_t instead of size_t for hashes?
+					return (uint32_t) h;
 				}
 			};