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<title>Issue 2188: Reverse iterator does not fully support targets that overload operator&amp;</title>
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<p><em>This page is a snapshot from the LWG issues list, see the <a href="lwg-active.html">Library Active Issues List</a> for more information and the meaning of <a href="lwg-active.html#C++14">C++14</a> status.</em></p>
<h3 id="2188"><a href="lwg-defects.html#2188">2188</a>. Reverse iterator does not fully support targets that overload <code>operator&amp;</code></h3>
<p><b>Section:</b> 24.5.1.6 <a href="https://wg21.link/reverse.iter.elem">[reverse.iter.elem]</a> <b>Status:</b> <a href="lwg-active.html#C++14">C++14</a>
 <b>Submitter:</b> Alisdair Meredith <b>Opened:</b> 2012-09-23 <b>Last modified:</b> 2021-06-06</p>
<p><b>Priority: </b>1
</p>
<p><b>View all other</b> <a href="lwg-index.html#reverse.iter.elem">issues</a> in [reverse.iter.elem].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#C++14">C++14</a> status.</p>
<p><b>Discussion:</b></p>
<p>
The specification for <code>reverse_iterator::operator-></code>
returns the address of the object yielded by dereferencing
with <code>operator*</code>, but does not have the usual
wording about returning the true address of the object.  As
<code>reverse_iterator</code> requires the adapted iterator have
at least the bidirectional iterator category, we know that
the returned reference is a true reference, and not a proxy,
hence we can use <code>std::addressof</code> on the reference
to get the right answer.
</p>
<p>
This will most likely show itself as an issue with a <code>list</code>
or <code>vector</code> of a type with such an overloaded operator,
where algorithms are likely to work with a forward iteration, but
not with reverse iteration.
</p>

<p><i>[2013-04-20, Bristol]</i></p>


<p>
Resolution: Goes to open now and move to review as soon as Daniel proposes a new wording.
</p>

<p><i>[2014-02-12 Issaquah meeting]</i></p>

<p>
Use <code>std::addressof</code> as the library uses elsewhere, then move as Immediate.
</p>



<p id="res-2188"><b>Proposed resolution:</b></p>
<p>
Revise  [reverse.iter.opref] p1, as indicated:
</p>
<p>
<i>Returns:</i> <code><ins>addressof</ins><del>&amp;(</del>operator*()<del>)</del></code>.
</p>





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