[Libreoffice] Git question again

Hello,

I'm a little lost with git again now.
Yesterday, i made first patches by using :
git commit -a

git format-patch HEAD~1


Now i do :
bin/g pull -r

and i got this :
===== components =====
usage: git merge-base [-a|--all] <commit> <commit>...

    -a, --all             outputs all common ancestors

usage: git merge-base [-a|--all] <commit> <commit>...

    -a, --all             outputs all common ancestors
...

You are not currently on a branch, so I cannot use any
'branch.<branchname>.merge' in your configuration file.
Please specify which remote branch you want to use on the command
line and try again (e.g. 'git pull <repository> <refspec>').
See git-pull(1) for details.


I don't understand why it talks about "branch". I don't want to merge 
anything, i just want to fetch the last version of the main repository.

Could anybody help me ?

Thanks in advance

Julien.