My Supervisor is not doing his job what do i do?

I work at a convenience type of store on a military base. I have a few laid back supervisors who i could say i am kind of friends with. Lately i've felt very taken advantage of by one supervisor. I am very capable and never need much help. He has come in late and expects me to lie to the manager if he asks me why we didn't punch in. He vanishes for hours at a time. I usually have no idea where he is. Just yesterday he came in super tired because he worked another job until 6am. He was dragging all day then vanished. I paged for his help and got no response. I paged again for another issue awhile later and still no answer. I went looking for him and he was ASLEEP in the break room. Then when another girl started her shift later in the day he made a comment saying something like.. "oh well since she's here i have to do something now."

I'm not one to go running to the boss, but i've had about enough. I don't know if i should just leave in alone, since i am planning on leaving soon anyway. Or if i should say speak to the manager and explain whats been happening.