From 00219bc0169f802fb8d4c015e2e1710df6f14b85 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?S=C3=A9bastien=20Loriot?= <sebastien.loriot@cgal.org>
Date: Wed, 3 Jan 2024 17:38:30 +0100
Subject: [PATCH] default arithmetic kernel when only boost mp is here

---
 Arithmetic_kernel/include/CGAL/Arithmetic_kernel.h       | 9 +++++++++
 .../include/CGAL/BOOST_MP_arithmetic_kernel.h            | 2 ++
 2 files changed, 11 insertions(+)

diff --git a/Arithmetic_kernel/include/CGAL/Arithmetic_kernel.h b/Arithmetic_kernel/include/CGAL/Arithmetic_kernel.h
index a01c7b70240..335d9e19d5d 100644
--- a/Arithmetic_kernel/include/CGAL/Arithmetic_kernel.h
+++ b/Arithmetic_kernel/include/CGAL/Arithmetic_kernel.h
@@ -59,6 +59,15 @@ typedef GMP_arithmetic_kernel Arithmetic_kernel;
 #endif // CGAL_USE_GMP
 #endif // CGAL_HAS_DEFAULT_ARITHMETIC_KERNEL
 
+#ifndef CGAL_HAS_DEFAULT_ARITHMETIC_KERNEL
+#include <CGAL/BOOST_MP_arithmetic_kernel.h>
+#if defined(CGAL_HAS_BOOST_MP_ARITHMETIC_KERNEL)
+namespace CGAL{
+typedef BOOST_cpp_arithmetic_kernel Arithmetic_kernel;
+}// namespace CGAL
+#define CGAL_HAS_DEFAULT_ARITHMETIC_KERNEL 1
+#endif // CGAL_USE_BOOST_MP
+#endif // CGAL_HAS_DEFAULT_ARITHMETIC_KERNEL
 
 // Macro to snap typedefs in Arithmetic_kernel
 #define CGAL_SNAP_ARITHMETIC_KERNEL_TYPEDEFS(AT) \
diff --git a/Arithmetic_kernel/include/CGAL/BOOST_MP_arithmetic_kernel.h b/Arithmetic_kernel/include/CGAL/BOOST_MP_arithmetic_kernel.h
index b1c1b1532e8..597e350bfd1 100644
--- a/Arithmetic_kernel/include/CGAL/BOOST_MP_arithmetic_kernel.h
+++ b/Arithmetic_kernel/include/CGAL/BOOST_MP_arithmetic_kernel.h
@@ -25,6 +25,8 @@
 //#include <boost/multiprecision/gmp.hpp>
 //#endif
 
+#define CGAL_HAS_BOOST_MP_ARITHMETIC_KERNEL
+
 // FIXME: the could be several kernels based on Boost.Multiprecision.
 
 namespace CGAL {