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<title>Issue 114: Placement forms example in error twice</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#TC1">TC1</a> status.</em></p>
<h3 id="114"><a href="lwg-defects.html#114">114</a>. Placement forms example in error twice</h3>
<p><b>Section:</b> 17.6.3.4 <a href="https://wg21.link/new.delete.placement">[new.delete.placement]</a> <b>Status:</b> <a href="lwg-active.html#TC1">TC1</a>
 <b>Submitter:</b> Steve Clamage <b>Opened:</b> 1998-10-28 <b>Last modified:</b> 2016-01-28</p>
<p><b>Priority: </b>Not Prioritized
</p>
<p><b>View all other</b> <a href="lwg-index.html#new.delete.placement">issues</a> in [new.delete.placement].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#TC1">TC1</a> status.</p>
<p><b>Duplicate of:</b> <a href="lwg-closed.html#196" title="Placement new example has alignment problems (Status: Dup)">196</a></p>
<p><b>Discussion:</b></p>
<p>Section 18.5.1.3 contains the following example: </p>

<pre>[Example: This can be useful for constructing an object at a known address:
        char place[sizeof(Something)];
        Something* p = new (place) Something();
 -end example]</pre>

<p>First code line: &quot;place&quot; need not have any special alignment, and the
following constructor could fail due to misaligned data.</p>

<p>Second code line: Aren't the parens on Something() incorrect?&nbsp; [Dublin: the LWG
believes the () are correct.]</p>

<p>Examples are not normative, but nevertheless should not show code that is invalid or
likely to fail.</p>


<p id="res-114"><b>Proposed resolution:</b></p>
<p>Replace the first line of code in the example in 
17.6.3.4 <a href="https://wg21.link/new.delete.placement">[new.delete.placement]</a> with:
</p>

<blockquote>
  <pre>void* place = operator new(sizeof(Something));</pre>
</blockquote>





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