When I ran Modelica libraries of Aixlib and  Modelica_Synchronous in Openmodelica, the compiler stopped for error. The error message is "Class Clock not found in scope Modelica_Synchronous.ClockSignals.Interfaces." I googled this error and someone said the reason is that Openmodelica have not supported the Modelica 3.3 feature of synchronous. 
So do I have any setting or solving method? Thank you.