Willis is the only one that has played at a level that would make him a certain pick, even then, he will need to have at least 3 more years at the same level.
Justin Smith probably does not have enough years left to play at a level that will get him in. He was very good year before last and last year he had some spectacular plays, but prior to that, he did very little to earn HOF consideration.
Vernon Davis has a lot to prove before he will get in. The homer in me would like to see him make it but reality says he has a lot of work to do.
Someone mentioned Iupati but it is way too soon to consider him in this conversation, IMO.
Gore was just on a bad team way too long to earn the kind of recognition he would need to get in. It is highly unlikely he will stay healthy long enough to put up the kind of numbers he would need.
No one else is in the conversation at this point.
(Moss is a Viking, not a 49er.)