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<title>Issue 796: ranlux48_base returns wrong value</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#NAD">NAD</a> status.</em></p>
<h3 id="796"><a href="lwg-closed.html#796">796</a>. <code>ranlux48_base</code> returns wrong value</h3>
<p><b>Section:</b> 29.5.6 <a href="https://wg21.link/rand.predef">[rand.predef]</a> <b>Status:</b> <a href="lwg-active.html#NAD">NAD</a>
 <b>Submitter:</b> P.J. Plauger <b>Opened:</b> 2008-02-09 <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#rand.predef">issues</a> in [rand.predef].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#NAD">NAD</a> status.</p>
<p><b>Discussion:</b></p>
<p>
The 10,000<sup>th</sup> value returned by <code>ranlux48_base</code> is supposed to be
61839128582725. We get 192113843633948. (Note that the underlying
generator was changed in Kona.)
</p>

<p><i>[
Bellevue:
]</i></p>


<blockquote><p>
Submitter withdraws defect.
</p></blockquote>



<p id="res-796"><b>Proposed resolution:</b></p>
<p>
Change 29.5.6 <a href="https://wg21.link/rand.predef">[rand.predef]</a>/p5:
</p>

<blockquote>
<pre>
typedef subtract_with_carry_engine&lt;uint_fast64_t, 48, 5, 12&gt; 
        ranlux48_base; 
</pre>
<blockquote><p>
<i>Required behavior:</i> The 10000<sup>th</sup> consecutive invocation of a default-constructed
object of type <code>ranlux48_base</code> shall produce the value
<del>61839128582725</del> <ins>192113843633948</ins>.
</p></blockquote>
</blockquote>





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