Although there is a limited amount of foreshadowing in 'The Road', there are some clear examples.
For example, when the boy asks the man about his friends, and the man responds that they all died, it may imply that it is inevitable that the man and the boy will suffer the same fate.
Furthermore, the man implies that he and the boy are the only 'good guys' left, for the majority of the novel at least, and as the 'bad guys' seem to be the dominant group in this new world, it is likely that in this case, evil will win over good, and the boy and the man will both suffer the same fate as the other good guys.
I'm sorry I couldn't think of much more at the moment, but I will answer again if I can come up with more points. I hope this has helped!