Could one cherry-pick the bug into the feature branch and have git automatically resolve it away
This can work if your fix introduces no conflicts. git clone https://gist.github.com/jbenet/7959265
, see the history and read the reflog I pasted there.
If you resolve conflict upon cherry-picking, you could remove the commit manually when rebasing on top of master, right before merging PR in (you can tag it/write a reminder in the commit message resolving the conflict).
But IMO, I'd rebase the feature branch on top of master when the hotfix was available. This is the same as pulling in any changes from master (inc other feature branches merged recently). Thus you're not worried about your branch being out of date. Depends on what your team likes to handle-- removing merged hotfixes, or rebasing often.