# rebase instead of merge
$ git merge v1
+If you have not yet pushed commits on ``v1``, though, the scenario has
+to become a bit more complex. Git refuses to update
+non-fast-forwardable branch, and you don't want to do force-pull
+because that would remove your non-pushed commits and you would need
+to recover. So you want to rebase ``v1`` but you cannot rebase
+non-current branch. Hence, checkout ``v1`` and rebase it before
+merging::
+
+ $ git checkout v1
+ $ git pull --rebase origin v1
+ $ git checkout v2
+ $ git pull --rebase origin v2
+ $ git merge v1
+
It is possible to configure git to make it fetch/pull a few branches
or all branches at once, so you can simply run