Apply patch from #8408.

Fixes #8408.

[SVN r83958]

test/boost_fallthrough_test.cpp

@@ -0,0 +1,20 @@
+//  Use, modification and distribution are subject to the  
+//  Boost Software License, Version 1.0. (See accompanying file  
+//  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) 
+
+#include <boost/config.hpp> 
+
+int test(int n) 
+{ 
+   switch (n) 
+   { 
+   case 0: 
+      n++; 
+      BOOST_FALLTHROUGH; 
+   case 1: 
+      n++; 
+      break; 
+   } 
+   return n; 
+}
+