Does struct hostent have a field "h_addr"?

In the GNU libc manual (or see here for the entire libc manual all on one page) they say:

Recall that the host might be connected to multiple networks and have different addresses on each one

They also provide the h_addr variable which is just the first element of the vector h_addr_list.

You missed this bit right under it:

#define h_addr h_addr_list[0] /* for backward compatibility */

So no, there is no problem.