 class=font-tt>-prefix-all-labels</span></span> option is given,
all record labels are prefixed, whether they occur several times or
not. If the <span class=machine><span class=font-tt>-keep-labels</span></span> option is given, no automatic prefixing
takes place; the naming of record labels is left entirely under the
user’s control, via <span class=syntax-token>mlname</span> annotations.</p></li></ul>
<h3 id="sec24" class="subsection">3.6 Unions</h3>
<p>IDL discriminated unions are translated to Caml s