rence due to Nullable annotation</p></div></div><div class="odoc-spec"><div class="spec value anchored" id="val-deref_str_undef"><a href="#val-deref_str_undef" class="anchor"></a><code><span><span class="keyword">val</span> deref_str_undef : <span><span>(<a href="../../IR/Procname/index.html#type-t">IR.Procname.t</a> * <a href="../../IBase/Location/index.html#type-t">IBase.Location.t</a>)</span> <span class="arrow">&#45;&gt;</span></span> <a href="#type-deref_str">deref_str</a></span></code></div><div class