title: How to create an empty master and raise a PR from existing branch
body: <p>I have a single branch in my repo: develop. Code has already been committed and pushed in there.</p>
  
  <p>There's no master branch in the repo.</p>
  
  <p>I'd like to create a master branch so I can raise a Pull Request into it.</p>
  
  <p>I've already tried two approaches:
  1. create the master branch from develop:</p>
  
  <pre><code>git checkout develop
  git checkout -b master develop
  </code></pre>
  
  <p>The problem here is there's nothing to compare: master and develop are already the same.</p>
  
  <ol start="2">
  <li>create the master branch from orphan:</li>
  </ol>
  
  <pre><code>git checkout --orphan master
  git reset --hard
  </code></pre>
  
  <p>The problem here is the branches have different history and I get:
  "there isn’t anything to compare. (branches) are entirely different commit histories"</p>
  
  <p>git version 2.17.2 (Apple Git-113)</p>
  
  <p>How do I create an empty master so I can raise a Pull Request from the already existing develop?</p>