using certificates from buffers instead of files is only available in boost 1.54 and later

include/libtorrent/torrent_handle.hpp

@@ -767,7 +767,9 @@ namespace libtorrent
 		// certificate in the .torrent file to be valid.
 		//
 		// The set_ssl_certificate_buffer() overload takes the actual certificate,
-		// private key and DH params as strings, rather than paths to files.
+		// private key and DH params as strings, rather than paths to files. This
+		// overload is only available when libtorrent is built against boost
+		// 1.54 or later.
 		// 
 		// ``cert`` is a path to the (signed) certificate in .pem format
 		// corresponding to this torrent.

src/torrent.cpp

@@ -4401,6 +4401,10 @@ namespace libtorrent
 	{
 		if (!m_ssl_ctx) return;
 
+#if BOOST_VERSION < 105400
+		if (alerts().should_post<torrent_error_alert>())
+			alerts().post_alert(torrent_error_alert(get_handle(), boost::system::errc::not_supported));
+#else
 		boost::asio::const_buffer certificate_buf(certificate.c_str(), certificate.size());
 
 		using boost::asio::ssl::context;
@@ -4427,6 +4431,7 @@ namespace libtorrent
 			if (alerts().should_post<torrent_error_alert>())
 				alerts().post_alert(torrent_error_alert(get_handle(), ec));
 		}
+#endif // BOOST_VERSION
 	}
 
 #endif