From 96a6cd878f56c5be4f0c11c95b9ee81438cf9dd3 Mon Sep 17 00:00:00 2001
From: jzmaddock <john@johnmaddock.co.uk>
Date: Sat, 4 Aug 2018 19:32:00 +0100
Subject: [PATCH] Apply fix for [[fallthrough]] attribute in Intel C++
 compiler. Fixes: https://github.com/boostorg/config/issues/211.

---
 include/boost/config/compiler/intel.hpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/include/boost/config/compiler/intel.hpp b/include/boost/config/compiler/intel.hpp
index e5fec7b7..f56807db 100644
--- a/include/boost/config/compiler/intel.hpp
+++ b/include/boost/config/compiler/intel.hpp
@@ -46,12 +46,17 @@
 #undef BOOST_GCC_VERSION
 #undef BOOST_GCC_CXX11
 #undef BOOST_GCC
+#undef BOOST_FALLTHROUGH
 
 // Broken in all versions up to 17 (newer versions not tested)
 #if (__INTEL_COMPILER <= 1700) && !defined(BOOST_NO_CXX14_CONSTEXPR)
 #  define BOOST_NO_CXX14_CONSTEXPR
 #endif
 
+#if (__INTEL_COMPILER >= 1800) && (__cplusplus >= 201703)
+#  define BOOST_FALLTHROUGH [[fallthrough]]
+#endif
+
 #endif // defined(_MSC_VER)
 
 #undef BOOST_COMPILER