This is a tool to keep git integration branches up to date. It takes a base branch (e.g. master), an integration branch (e.g. pu) to update, and a topic branch queue. The integration branch will be reset to the base branch (or some intermediate point, if possible), and each topic branch in the queue will be merged in, one-by-one. After each branch is merged, make will be called to verify the project still builds. If a branch does not merge cleanly (and rerere can't fix it), or if make does not complete succesfully, the branch will be excluded. The result will be a newly constructed integration branch built off of the specified base, with all of the topic branches from the queue merged (except those which don't merge cleanly or which break the build).