From 3f3691a48e4fece4f072cf8488e4772f2f99d810 Mon Sep 17 00:00:00 2001
From: Andreas Fabri <andreas.fabri@geometryfactory.com>
Date: Thu, 11 Jan 2024 08:43:05 +0000
Subject: [PATCH 1/2] Add testcase that shows the problem

---
 .../Segment_Delaunay_graph_2/issue7972.cpp    | 21 +++++++++++++++++++
 1 file changed, 21 insertions(+)
 create mode 100644 Segment_Delaunay_graph_2/test/Segment_Delaunay_graph_2/issue7972.cpp

diff --git a/Segment_Delaunay_graph_2/test/Segment_Delaunay_graph_2/issue7972.cpp b/Segment_Delaunay_graph_2/test/Segment_Delaunay_graph_2/issue7972.cpp
new file mode 100644
index 00000000000..6dd4a4e5e2b
--- /dev/null
+++ b/Segment_Delaunay_graph_2/test/Segment_Delaunay_graph_2/issue7972.cpp
@@ -0,0 +1,21 @@
+
+#include <CGAL/Segment_Delaunay_graph_2.h>
+#include <CGAL/Segment_Delaunay_graph_traits_2.h>
+#include <CGAL/Exact_predicates_exact_constructions_kernel.h>
+
+typedef CGAL::Exact_predicates_exact_constructions_kernel K;
+typedef CGAL::Segment_Delaunay_graph_traits_2<K>          Gt;
+typedef CGAL::Segment_Delaunay_graph_2<Gt>                SDG2;
+
+int main() {
+    auto segments = std::vector({
+        CGAL::Segment_2<K>(
+            CGAL::Point_2<K>(0.0, 0.0),
+            CGAL::Point_2<K>(1.0, 0.0))
+    });
+
+    SDG2 delaunay;
+    delaunay.insert_segments(segments.begin(), segments.end());
+
+    return 0;
+}

From 23e56a8e3e2df7b1c5e9cd659f1b10c35e41940d Mon Sep 17 00:00:00 2001
From: Andreas Fabri <andreas.fabri@geometryfactory.com>
Date: Thu, 11 Jan 2024 08:43:48 +0000
Subject: [PATCH 2/2] In case of Epeck the source of a segment is not a
 reference

---
 .../include/CGAL/Segment_Delaunay_graph_2.h                   | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Segment_Delaunay_graph_2/include/CGAL/Segment_Delaunay_graph_2.h b/Segment_Delaunay_graph_2/include/CGAL/Segment_Delaunay_graph_2.h
index 1c684d32202..05a199a5bff 100644
--- a/Segment_Delaunay_graph_2/include/CGAL/Segment_Delaunay_graph_2.h
+++ b/Segment_Delaunay_graph_2/include/CGAL/Segment_Delaunay_graph_2.h
@@ -632,11 +632,11 @@ class Segment_Delaunay_graph_2
   }
 
   template <class Segment_2>
-  static const Point_2& get_source(const Segment_2& segment){
+  static Point_2 get_source(const Segment_2& segment){
     return segment.source();
   }
   template <class Segment_2>
-  static const Point_2& get_target(const Segment_2& segment){
+  static Point_2 get_target(const Segment_2& segment){
     return segment.target();
   }