title: How does one work on a new git branch that depends on another git branch that is not yet merged?
body: <p>Here's my scenario:</p>
  
  <ul>
  <li><p>My project is following the topic branching pattern.</p></li>
  <li><p>I create a branch to fix some problems, let's call this branch problem_fixes. I make my changes, and submit a pull request.</p></li>
  <li><p>I need to start work on a new feature, so I create a second branch called my_feature and commit a bunch of changes.</p></li>
  <li><p>At some point I realize my_feature is dependent on problem_fixes which has not yet been accepted and merged (the my_feature branch relies on some of the fixes from the first branch and I can't make progress without them).</p></li>
  </ul>
  
  <p>Short of badgering my project lead to accept and merge my first branch faster, what is the best process to follow here?</p>
  
  <p>I am wondering if I need to start a new, third branch based on problem_fixes (instead of master) and merge in my commits to my_feature? Or will it be okay if I simply merge problem_fixes into my_feature and continue work -- assuming problem_fixes is merged into master first, when my_feature is merged it should theoretically be okay(?)</p>