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<title>Issue 3945: &sect;[cstdarg.syn] 'Compatible types' are undefined</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#New">New</a> status.</em></p>
<h3 id="3945"><a href="lwg-active.html#3945">3945</a>. &sect;[cstdarg.syn] 'Compatible types' are undefined</h3>
<p><b>Section:</b> 17.14.2 <a href="https://wg21.link/cstdarg.syn">[cstdarg.syn]</a> <b>Status:</b> <a href="lwg-active.html#New">New</a>
 <b>Submitter:</b> Lukas Barth <b>Opened:</b> 2023-06-08 <b>Last modified:</b> 2023-06-12</p>
<p><b>Priority: </b>3
</p>
<p><b>View all issues with</b> <a href="lwg-status.html#New">New</a> status.</p>
<p><b>Discussion:</b></p>
<p>
Subclause 17.14.2 <a href="https://wg21.link/cstdarg.syn">[cstdarg.syn]</a> p1 bullet (1.2) states (among other things): 
</p>
<blockquote style="border-left: 3px solid #ccc;padding-left: 15px;"><p>
[&hellip;]  If the parameter <code>parmN</code> is of a reference type, or of a type that is not
compatible with the type that results when passing an argument for which there is no parameter, 
the behavior is undefined.
</p></blockquote>
<p>
Unlike the C standard, the C++ standard has no notion of 'compatible
types', thus the meaning of this sentence unclear.
</p>


<p><i>[2023-06-12; Reflector poll]</i></p>

<p>
Set priority to 3 after reflector poll.
</p>



<p id="res-3945"><b>Proposed resolution:</b></p>





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