Part of me is saying that he's alive. Unless, he had a way of coming back, different from how the Dark Lord does. Dumbledore must know a lot of ancient magic, if he knew to send Harry to his aunt's and uncle's. Either that, he was truly meant to die, so Harry would be able to defeat the Dark Lord. Maybe Dumbledore, meant to keep Harry their, so he could seem him killed, to motivate him into doing the right thing.