From aa3ccf5cb51d709c1f3cdfafe870e6b1ba93fb6c Mon Sep 17 00:00:00 2001
From: Thomas Krijnen <t.krijnen@gmail.com>
Date: Sun, 20 Sep 2020 12:19:43 +0200
Subject: [PATCH] const lvalue things

---
 src/ifcgeom/kernels/cgal/CgalKernel.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/ifcgeom/kernels/cgal/CgalKernel.cpp b/src/ifcgeom/kernels/cgal/CgalKernel.cpp
index e178c6d5ec..ca3aba9997 100644
--- a/src/ifcgeom/kernels/cgal/CgalKernel.cpp
+++ b/src/ifcgeom/kernels/cgal/CgalKernel.cpp
@@ -139,7 +139,7 @@ CGAL::Nef_polyhedron_3<Kernel_> ifcopenshell::geometry::utils::create_nef_polyhe
 
 namespace {
 	template <typename T, typename Fn>
-	void visit(const taxonomy::collection* c, Fn& fn) {
+	void visit(const taxonomy::collection* c, const Fn& fn) {
 		static_assert(std::is_same<T, taxonomy::point3>::value, "@todo Only implemented for point3");
 		for (auto& i : c->children) {
 			if (dynamic_cast<const taxonomy::collection*>(i)) {
@@ -1286,7 +1286,7 @@ namespace {
 
 		distances = { +inf, -inf };
 
-		for (auto& e : edges(shape)) {
+		for (const auto& e : edges(shape)) {
 			const auto& p0 = e.halfedge()->vertex()->point();
 			const auto& p1 = e.halfedge()->next()->vertex()->point();
 			auto p01 = p1 - p0;