From b984dce2226f9e341cfb2fa72934666a9e871f86 Mon Sep 17 00:00:00 2001
From: Andreas Fabri <andreas.fabri@geometryfactory.com>
Date: Fri, 11 May 2018 08:32:11 +0100
Subject: [PATCH] Address all remaining points of issue #1384, but the renderer

---
 .../include/CGAL/Arr_circle_segment_traits_2.h             | 7 ++++++-
 Arrangement_on_surface_2/include/CGAL/Arr_conic_traits_2.h | 7 ++++++-
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/Arrangement_on_surface_2/include/CGAL/Arr_circle_segment_traits_2.h b/Arrangement_on_surface_2/include/CGAL/Arr_circle_segment_traits_2.h
index bdbd53d20a4..6a45bafe0c9 100644
--- a/Arrangement_on_surface_2/include/CGAL/Arr_circle_segment_traits_2.h
+++ b/Arrangement_on_surface_2/include/CGAL/Arr_circle_segment_traits_2.h
@@ -31,6 +31,7 @@
  * The header file for the Arr_circle_segment_traits_2<Kenrel> class.
  */
 
+#include <CGAL/atomic.h>
 #include <CGAL/tags.h>
 #include <CGAL/Arr_tags.h>
 #include <CGAL/Arr_geometry_traits/Circle_segment_2.h>
@@ -84,7 +85,11 @@ public:
   /*! Get the next curve index. */
   static unsigned int get_index ()
   {
-    static unsigned int index = 0;
+#ifdef CGAL_NO_ATOMIC
+    static unsigned int index;
+#else
+    static CGAL::cpp11::atomic<unsigned int> index;
+#endif
     return (++index);
   }
 
diff --git a/Arrangement_on_surface_2/include/CGAL/Arr_conic_traits_2.h b/Arrangement_on_surface_2/include/CGAL/Arr_conic_traits_2.h
index 69e7e29b755..d84c112662c 100644
--- a/Arrangement_on_surface_2/include/CGAL/Arr_conic_traits_2.h
+++ b/Arrangement_on_surface_2/include/CGAL/Arr_conic_traits_2.h
@@ -31,6 +31,7 @@
  * The conic traits-class for the arrangement package.
  */
 
+#include <CGAL/atomic.h>
 #include <CGAL/tags.h>
 #include <CGAL/Arr_tags.h>
 #include <CGAL/Arr_geometry_traits/Conic_arc_2.h>
@@ -114,7 +115,11 @@ public:
   /*! Get the next conic index. */
   static unsigned int get_index ()
   {
-    static unsigned int index = 0;
+#ifdef CGAL_NO_ATOMIC
+    static unsigned int index;
+#else
+    static CGAL::cpp11::atomic<unsigned int> index;
+#endif
     return (++index);
   }