IRED</span></code> is set
to true, <span class="target" id="index-2-prop_tgt:&lt;LANG&gt;_STANDARD"></span><a class="reference internal" href="LANG_STANDARD.html#prop_tgt:&lt;LANG&gt;_STANDARD" title="&lt;LANG&gt;_STANDARD"><code class="xref cmake cmake-prop_tgt docutils literal notranslate"><span class="pre">&lt;LANG&gt;_STANDARD</span></code></a> becomes a hard requirement and a fatal
error will be issued if that requirement cannot be met.</p>
<p>Note that the actual language standard used may be higher t