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<title>Issue 2425: operator delete(void*, size_t) doesn't invalidate pointers sufficiently</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++17">C++17</a> status.</em></p>
<h3 id="2425"><a href="lwg-defects.html#2425">2425</a>. <code>operator delete(void*, size_t)</code> doesn't invalidate pointers sufficiently</h3>
<p><b>Section:</b> 17.6.3 <a href="https://wg21.link/new.delete">[new.delete]</a> <b>Status:</b> <a href="lwg-active.html#C++17">C++17</a>
 <b>Submitter:</b> Richard Smith <b>Opened:</b> 2014-08-29 <b>Last modified:</b> 2017-07-30</p>
<p><b>Priority: </b>0
</p>
<p><b>View all other</b> <a href="lwg-index.html#new.delete">issues</a> in [new.delete].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#C++17">C++17</a> status.</p>
<p><b>Discussion:</b></p>
<p>
17.6.3.2 <a href="https://wg21.link/new.delete.single">[new.delete.single]</a>/12 says:
</p>
<blockquote><p>
<i>Requires</i>: <code>ptr</code> shall be a null pointer or its value shall be a value returned by an earlier call to the 
(possibly replaced) <code>operator new(std::size_t)</code> or <code>operator new(std::size_t,const std::nothrow_t&amp;)</code> 
which has not been invalidated by an intervening call to <code>operator delete(void*)</code>.
</p></blockquote>
<p>
This should say:
</p>
<blockquote><p>
[&hellip;] by an intervening call to <code>operator delete(void*)</code> <ins>or <code>operator delete(void*, std::size_t)</code></ins>.
</p></blockquote>
<p>
Likewise at the end of 17.6.3.3 <a href="https://wg21.link/new.delete.array">[new.delete.array]</a>/11, <ins><code>operator delete[](void*, std::size_t)</code></ins>.
</p>

<p><i>[Urbana 2014-11-07: Move to Ready]</i></p>




<p id="res-2425"><b>Proposed resolution:</b></p>
<ol>
<li><p>Change 17.6.3.2 <a href="https://wg21.link/new.delete.single">[new.delete.single]</a>p12 as indicated:</p>

<blockquote>
<p>
-12- <i>Requires</i>: <code>ptr</code> shall be a null pointer or its value shall be a value returned by an earlier call to the 
(possibly replaced) <code>operator new(std::size_t)</code> or <code>operator new(std::size_t,const std::nothrow_t&amp;)</code> which 
has not been invalidated by an intervening call to <code>operator delete(void*)</code> <ins>or 
<code>operator delete(void*, std::size_t)</code></ins>.
</p>
</blockquote>
</li>

<li><p>Change 17.6.3.3 <a href="https://wg21.link/new.delete.array">[new.delete.array]</a>p11 as indicated:</p>

<blockquote>
<p>
-11- <i>Requires</i>: <code>ptr</code> shall be a null pointer or its value shall be the value returned by an earlier call to 
<code>operator new[](std::size_t)</code> or <code>operator new[](std::size_t,const std::nothrow_t&amp;)</code> which 
has not been invalidated by an intervening call to <code>operator delete[](void*)</code> <ins>or 
<code>operator delete[](void*, std::size_t)</code></ins>.
</p>
</blockquote>
</li>
</ol>





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