Add missing cast for C++
Add missing cast for C++

tbeu/msgpack-modelica,tbeu/msgpack-modelica,tbeu/msgpack-modelica,modelica-3rdparty/msgpack-modelica,modelica-3rdparty/msgpack-modelica,modelica-3rdparty/msgpack-modelica,modelica-3rdparty/msgpack-modelica,tbeu/msgpack-modelica,tbeu/msgpack-modelica