title: What does "1 line adds whitespace errors" mean when applying a patch?
body: <p>I'm editing some markdown files of a cloned remote repository, and wanted to test creating and applying patches from one branch to another. However, every time I make any change at all, I get the following message during <code>git apply</code>:</p>
  
  <pre><code>0001-b.patch:16: trailing whitespace.
  warning: 1 line adds whitespace errors.
  </code></pre>
  
  <p>(This is happening on my Mac, and I don't know where the original code was created.)</p>
  
  <p>What does the warning message mean, and do I need to care?</p>