git push异常具体如下（一般发生在首次推送）:
No refs in common and none specified; doing nothing. Perhaps you should specify a branch such as 'master'

没有指定推送到哪个分支里去。
解决方案:使用 git push origin master 可以指定推送该远程库的主分支去

git init

git remote add origin http://dev.gitlab.com/root/test.git

git add .

git commit -m "init file

git push origin master

error: failed to push some refs to 'http://dev.gitlab.com/root/test.git'
hint: Updates were rejected because the tip of your current branch is behind
hint: its remote counterpart. Merge the remote changes (e.g. 'git pull')
hint: before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.

git checkout master
git pull origin master  或者 git pull origin master --allow-unrelated-histories