brew update doesn't work

[sberghel]

When I try to run a brew update, the following happens:

sberghel:~ skye$ brew update
remote: Counting objects: 77, done.
remote: Compressing objects: 100% (28/28), done.
error: insufficient permission for adding an object to repository database .git/objects

fatal: failed to write object
fatal: unpack-objects failed

Error: Failed while executing git pull origin refs/heads/master:refs/remotes/origin/master

[mxcl]

Sounds like you need to fix the permissions on your .git directory.

chown -R $(whoami) /usr/local.git should do it.

[2bits]

ls -ld $HOMEBREW_PREFIX
ls -la $HOMEBREW_PREFIX
brew --config
brew doctor

[sberghel]

Changing my permissions did the trick, thanks.

[mattcg]

There's a missing slash in @mxcl's command above. It's actually

chown -R $(whoami) /usr/local/.git

[mralexgray]

i had to do cd /usr/local/Library && git stash && git clean -f

[EricAllsop]

Thanks mralexgray the stash and clean worked for me.

[moontan]

Hi, I also get Error: Failure while executing: git pull -q origin refs/heads/master:refs/remotes/origin/master when trying brew update but none of the above solutions work for me. I haven't updated in two or three months.

[moontan]

Oh, I just noticed there's another error before that:
The following untracked working tree files would be overwritten by merge: (…) Please move or remove them before you can merge.
Perhaps I should just follow these instructions.

[ofloveandhate]

i WAS getting:

error: Your local changes to the following files would be overwritten by merge: Library/Formula/vtk.rb Please, commit your changes or stash them before you can merge. Aborting Error: Failure while executing: git pull -q origin refs/heads/master:refs/remotes/origin/master

but mralexgray helped out. the ol' copypasta into terminal, and bam, brewing again:
cd /usr/local/Library && git stash && git clean -f

[richardjortega]

Thanks @mralexgray the stash and clean worked for me as well.

[fgarcia]

In my case I had the same problem and @mralexgray did not work for me. I even nuked the whole thing:

rm -rf /usr/local/.git
brew update

That did not solve the problem either. I had to:

sudo brew update

And now it is working again, so far no "root" owned files within the .git repo

[MikeMcQuaid]

Do sudo chown -R $USER /usr/local. Don't run brew commands with sudo.

[fgarcia]

I already did that, and I know that we should not mix "sudo" and "brew" together. Even so, the "sudo brew update" was the only thing that worked.

However immediately afterwards I did chown to my user the whole tree, just to make sure everything stays under my user access. Hopefully that might help someone else, but still... it was such an odd solution