How to define a struct variable like in C with Matlab

I'm currently working on a model which a modelize with stateflow simulink. I have numerous struct variable that I want to set up within my model but I cannot figure out how can achieve that with simulink matlab. I figured that I can use int, double, u_int, boolean, etc ... but how about if I want to customize my variable to be heteregeneous ?

Can anyone propose an idea to do that ?

Thanks in advance