update boost on linux

linx64/include/boost/asio/ssl/error.hpp

@@ -2,7 +2,7 @@
 // ssl/error.hpp
 // ~~~~~~~~~~~~~
 //
-// Copyright (c) 2003-2017 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
 //
 // Distributed under 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)
@@ -45,12 +45,24 @@ enum stream_errors
 {
 #if defined(GENERATING_DOCUMENTATION)
   /// The underlying stream closed before the ssl stream gracefully shut down.
-  stream_truncated
-#elif (OPENSSL_VERSION_NUMBER < 0x10100000L) && !defined(OPENSSL_IS_BORINGSSL)
-  stream_truncated = ERR_PACK(ERR_LIB_SSL, 0, SSL_R_SHORT_READ)
-#else
-  stream_truncated = 1
-#endif
+  stream_truncated,
+
+  /// The underlying SSL library returned a system error without providing
+  /// further information.
+  unspecified_system_error,
+
+  /// The underlying SSL library generated an unexpected result from a function
+  /// call.
+  unexpected_result
+#else // defined(GENERATING_DOCUMENTATION)
+# if (OPENSSL_VERSION_NUMBER < 0x10100000L) && !defined(OPENSSL_IS_BORINGSSL)
+  stream_truncated = ERR_PACK(ERR_LIB_SSL, 0, SSL_R_SHORT_READ),
+# else
+  stream_truncated = 1,
+# endif
+  unspecified_system_error = 2,
+  unexpected_result = 3
+#endif // defined(GENERATING_DOCUMENTATION)
 };
 
 extern BOOST_ASIO_DECL