I recently flew to Arkansas for, of all things, Photo Center Manager School. Naturally, I had film, both exposed and unexposed in my carry on, also had some in my checked luggage.
I flew out of Bradley, connected at O'Hare. On the return I flew from Northwest Regional in Arkansas, back to O'Hare and home. Nothing happened to the film. It was just fine. Xrays do not harm film. That was one of the big questions at school. Lead lined bags only cause them to boost the xrays, hold up lines and are a general waste of money.
The warnings you will see on film regarding xrays are for the xrays used at hospitals, very powerful, nothing like the airports. If they could do damage to film, they would do damage to the operators of the machines. If there was any chance of harm to a human they would wear lead, they do not.
Of a much greater and surer(?) risk is the new scanner they are using at the post office, that will definitely kill the film.