, Allocator&gt;::construct</a>(U* ptr) <span class="keyword">noexcept</span>(std::is_nothrow_default_constructible_v&lt;U&gt;)</div>
<div class="line"><a id="l00133" name="l00133"></a><span class="lineno">  133</span>{</div>
<div class="line"><a id="l00134" name="l00134"></a><span class="lineno">  134</span>  <span class="comment">// If U&#39;s default-init = value-init, this changes no behavior.  Otherwise this performs default-init (~no-op).</span></div>
<div class="line"><a id="l00135" name="l00135"></a>