title: What to do if git-am fails with "does not match index"?
body: <p>I'm trying to apply a git patch created by someone else with <code>git-format-patch</code>. The patch was made against one commit behind HEAD, but as I understand it this shouldn't matter. When I run <code>git am 0001.patch</code>, I get the error:</p>
  
  <p><code>error: source.c: does not match index</code></p>
  
  <p>I'm not too familiar with the format of git patches, but it does seem that the indexes don't match, however the source does match.</p>
  
  <p>What's the best way to fix this? Manually change the indexes to match? Or should I <code>git-apply</code> and then copy the author and description information when I commit?</p>