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    <p>Yes it is the correct behavior.</p> <p>§20.7.1.2.2[unique.ptr.single.dtor]/2:</p> <blockquote> <h3><code>unique_ptr</code> destructor</h3> <p><em>Effects</em>: If <code>get() == nullptr</code> there are no effects. Otherwise <code>get_deleter()(get())</code>.</p> </blockquote> <p>§20.7.2.2.2[util.smartptr.shared.dest]/1:</p> <blockquote> <h3><code>shared_ptr</code> destructor</h3> <p><em>Effects</em>:</p> <ul> <li>If <code>*this</code> is <em>empty</em> or shares ownership with another <code>shared_ptr</code> instance (<code>use_count() &gt; 1</code>), there are no side effects.</li> <li>Otherwise, if <code>*this</code> <em>owns</em> an object <code>p</code> and a deleter <code>d</code>, <code>d(p)</code> is called.</li> <li>Otherwise, <code>*this</code> <em>owns</em> a pointer <code>p</code>, and delete <code>p</code> is called.</li> </ul> </blockquote> <p>So there should be no effect since the shared_ptr is empty? Wrong, because providing the a pointer makes the shared_ptr <em>not</em> empty, even if the pointer is null.</p> <p>§20.7.2.2.1[util.smartptr.shared.const]/8–10</p> <blockquote> <p><code>shared_ptr</code> constructors</p> <pre><code>template&lt;class Y, class D&gt; shared_ptr(Y* p, D d); template&lt;class Y, class D, class A&gt; shared_ptr(Y* p, D d, A a); template &lt;class D&gt; shared_ptr(nullptr_t p, D d); template &lt;class D, class A&gt; shared_ptr(nullptr_t p, D d, A a); </code></pre> <p><em>Requires:</em> <code>p</code> shall be convertible to <code>T*</code>. …</p> <p><em>Effects:</em> Constructs a <code>shared_ptr</code> object that <em>owns</em> the object <code>p</code> and the deleter <code>d</code>.</p> <p><em>Postconditions:</em> <code>use_count() == 1 &amp;&amp; get() == p</code>.</p> </blockquote> <p>This means the shared_ptr <em>owns</em> the nullptr. Thus the deleter will be called when the shared_ptr is destroyed.</p>
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    1. PODoes the standard behavior for deleters differ between shared_ptr and unique_ptr in the case of null pointers?
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    1. COI see. Thank you also for your reply (sorry that Jon appears to have beaten you to the punch). You and Jon definitely know your stuff!
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