Issue
Why is Git not allowing me to fast forward merge anymore? If I try to force it using --ff-only, I get the message “fatal: Not possible to fast-forward, aborting.” I realize that there are huge advantages to merge --no-ff, but I’m just puzzled why I can’t --ff-only now?
Solution
Your branch is no longer directly based off of the branch you’re trying to merge it into – e.g. another commit was added to the destination branch that isn’t in your branch. Thus, you can’t fast-forward into it (because fast-forward requires your branch to completely contain the destination branch).
You can rebase your branch on top of the destination branch (git rebase <destination branch>) to rework the commits such that they will fast forward into it, or you can do a regular merge.
Answered By – Amber
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