From e12c3504554ef637eb4bc877f57a36e2f0a82920 Mon Sep 17 00:00:00 2001
From: Edward Diener <eldlistmailingz@tropicsoft.com>
Date: Sat, 14 Dec 2019 18:06:07 -0500
Subject: [PATCH] VC++ below 14.0 does not support the full C++11 unrestricted
 unions spec.

---
 include/boost/config/compiler/visualc.hpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/include/boost/config/compiler/visualc.hpp b/include/boost/config/compiler/visualc.hpp
index 092252e3..4c47b120 100644
--- a/include/boost/config/compiler/visualc.hpp
+++ b/include/boost/config/compiler/visualc.hpp
@@ -185,6 +185,7 @@
 #  define BOOST_NO_CXX14_GENERIC_LAMBDAS
 #  define BOOST_NO_CXX14_DIGIT_SEPARATORS
 #  define BOOST_NO_CXX11_THREAD_LOCAL
+#  define BOOST_NO_CXX11_UNRESTRICTED_UNION
 #endif
 // C++11 features supported by VC++ 14 update 3 (aka 2015)
 //