Hi to all once again, I think I solve the problem by substituting in the intraHO class constructor: intraHOfailure.setHOexeFunction(&intraHO::execute_intraHO); intraHCSfailure.setHOexeFunction(&intraHO::execute_HCS_HO); intraHOfailure.setFailureFunction(&intraHO::failure_intraHO); intraHCSfailure.setFailureFunction(&intraHO::failure_HCS_HO); gcc is really -pedantic without to specify the mentioned option :) Regards, Iavor.