How to return a complex return value?

Currently I am writing some assembly language procedures. As some convention says, when I want to return some value to the caller, say an integer, I should return it in the EAX register. Now I am wondering what if I want to return a float, a double, an enum, or even a complex struct. How to return these type of values?

I can think of returning an address in the EAX which points to the real value in memory. But is it the standard way?

Many thanks~~~