Git differences are not updated with the latest changes from start point branch
<p>I have a branch, lets call this <code>Y</code>, which was <code>git checkout -b</code> off a branch <code>X</code>. When I look at the diffs for latest commits in <code>Y</code> I see it compared to <code>X</code> at the commit from which <code>Y</code> was branched. I want the diffs to instead be compared to the latest commit <code>X</code>. How can I update this?</p>