title: How to prevent merge from falling back to normal merge strategy when a fast-forward merge is not possible?
body: <p>The <code>git merge</code> command has an option to perform fast-forward merge, but this is not what I want, because if it can't do a fast-forward merge, it uses the normal merge.</p>
  
  <p>Is there a git command which <strong>only</strong> performs a fast-forward merge (from the tracked remote branch) and does nothing if the fast-forward merge is not possible?</p>