git push报错error: failed to push some refs to 'xxx.com:

GIT上传项目到码云时报错

$ git push -u origin master
To https://gitee.com/lixiaoyang123/sso.git
 ! [rejected]        master -> master (fetch first)
error: failed to push some refs to 'https://gitee.com/xxx/sso.git'
hint: Updates were rejected because the remote contains work that you do
hint: not have locally. This is usually caused by another repository pushing
hint: to the same ref. You may want to first integrate the remote changes
hint: (e.g., 'git pull ...') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.

解决方法
第一

$  git pull --rebase origin master

第二 上传

git push -u origin master

问题原因
码云远程仓库中的README.md文件不在本地仓库中。