I got the message in the subject when pushing to github today. Yes I know it's github, not git. But according to stackoveflow  it's a local problem. Which makes me think, if we know exactly what this is (or at least roughly the problem area), maybe we could improve git to catch it locally in the first place (and because other git servers may not have the same protection as github). Jeff maybe you can reveal something about this "fatal error in commit_refs"? I'm sure it's not in git code. But I would understand if the answer is "no".
$ git push origin +ZZZ Counting objects: 95, done. Delta compression using up to 4 threads. Compressing objects: 100% (39/39), done. Writing objects: 100% (95/95), 15.78 KiB | 0 bytes/s, done. Total 95 (delta 80), reused 69 (delta 56) remote: Resolving deltas: 100% (80/80), completed with 49 local objects. remote: fatal error in commit_refs To github.com:XXX/YYY.git ! [remote rejected] ZZZ -> ZZZ (failure) error: failed to push some refs to 'g...@github.com:XXX/YYY.git'  https://stackoverflow.com/questions/37341960/how-do-i-fix-remote-fatal-error-in-commit-refs-errors-trying-to-push-with-git -- Duy