Yes you do. Merge master into your branch. Rebasing long-running branches is a nightmare, because every diff you replay will probably result in a conflict, and if you have hundreds of commits, you could be there for several days rebasing. Merges, even massive merges, generally don't take more than a few hours. All project size dependent of course, but the ratio of work is about right: 5-10x more work for a rebase over a commit.