title: got 'fatal: branch 'master' does not exist' in git
body: <p>using <code>git</code> for a while, it's very powerful and beautiful..  </p>
  
  <p>but also got some confused about  it:  </p>
  
  <p>it should under branch master after I init a git repo, isn't it?   </p>
  
  <p>but <code>git branch -a</code>, i got nothing man.<br>
  and I got <code>fatal: branch 'master' does not exist</code> when I try to set upstream for my branch.  </p>
  
  <pre><code>users@debian MINGW64 ~/Desktop/taste
  $ git init
  Initialized empty Git repository in C:/Users/users/Desktop/taste/.git/
  
  users@debian MINGW64 ~/Desktop/taste (master)
  $ git remote add origin git@gitee.com:greedev/Test.git
  
  users@debian MINGW64 ~/Desktop/taste (master)
  $ git branch -u origin/master
  fatal: branch 'master' does not exist
  
  users@debian MINGW64 ~/Desktop/taste (master)
  $ git branch -a
  
  users@debian MINGW64 ~/Desktop/taste (master)
  $ git fetch
  The authenticity of host 'gitee.com (120.55.226.24)' can't be established.
  ECDSA key fingerprint is SHA256:FQGC9Kn/eye1W8icdBgrQp+KkGYoFgbVr17bmjey0Wc.
  Are you sure you want to continue connecting (yes/no)? yes
  Warning: Permanently added 'gitee.com,120.55.226.24' (ECDSA) to the list of know                n hosts.
  remote: Counting objects: 7, done.
  remote: Compressing objects: 100% (6/6), done.
  remote: Total 7 (delta 0), reused 0 (delta 0)
  Unpacking objects: 100% (7/7), done.
  From gitee.com:greedev/Test
  * [new branch]      master     -&gt; origin/master
  
  users@debian MINGW64 ~/Desktop/taste (master)
  $ git branch -a
    remotes/origin/master
  
  users@debian MINGW64 ~/Desktop/taste (master)
  $ git branch -u origin/master
  fatal: branch 'master' does not exist
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/c105A.png" alt="enter image description here"></p>