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    CWG Issue 2645</TITLE>
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<P><EM>This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21
  Core Issues List revision 118b.
  See http://www.open-std.org/jtc1/sc22/wg21/ for the official
  list.</EM></P>
<P>2025-09-28</P>
<HR>
<A NAME="2645"></A><H4>2645.
  
Unused term "default argument promotions"
</H4>
<B>Section: </B>7.6.1.3&#160; [<A href="https://wg21.link/expr.call">expr.call</A>]
 &#160;&#160;&#160;

 <B>Status: </B>C++23
 &#160;&#160;&#160;

 <B>Submitter: </B>US
 &#160;&#160;&#160;

 <B>Date: </B>2022-11-03<BR><BR>


<A href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2022/p2720r0.pdf#US15-044">P2720R0 comment
  US&#160;15-044<BR></A>

<P>[Accepted as a DR at the November, 2022 meeting.]</P>

<P>The phrase "default argument promotions" is apparently unused.</P>

<P><U>Possible resolution [SUPERSEDED]:</U></P>

<OL>

<LI>

<P>Change in 7.6.1.3 [<A href="https://wg21.link/expr.call#12">expr.call</A>] paragraph 12 as follows:</P>

<BLOCKQUOTE>

...If the argument has integral or enumeration type that is
subject to the integral promotions (7.3.7 [<A href="https://wg21.link/conv.prom">conv.prom</A>]), or a
floating-point type that is subject to the floating-point promotion
(7.3.8 [<A href="https://wg21.link/conv.fpprom">conv.fpprom</A>]), the value of the argument is converted
to the promoted type before the call.  <DEL>These promotions are referred to
as the <I>default argument promotion</I>s.</DEL>

</BLOCKQUOTE>

</LI>

<LI>

<P>Change in 17.14.2 [<A href="https://wg21.link/cstdarg.syn">cstdarg.syn</A>] as follows:</P>

<P>See also: ISO C <DEL>7.16.1.1</DEL> <INS>7.16.1</INS>
</P>

</LI>

</OL>

<P><B>CWG 2022-11-10</B></P>

<P>The phrase is useful and needed to override C's deviating
definition, as applicable to <TT>va_arg</TT>.</P>

<P><B>Proposed resolution (approved by CWG and LWG 2022-11-11):</B></P>

<P>Change in 17.14.2 [<A href="https://wg21.link/cstdarg.syn">cstdarg.syn</A>] as follows:</P>

<BLOCKQUOTE>

The contents of the header &lt;cstdarg&gt; are the same as the C
standard library header &lt;stdarg.h&gt;, with the following changes:
<INS>In lieu of the default argument promotions specified in ISO C
6.5.2.2, the definition in 7.6.1.3 [<A href="https://wg21.link/expr.call">expr.call</A>] applies.</INS>
The restrictions that ISO C places on the second parameter to
the <TT>va_start</TT> macro in header &lt;stdarg.h&gt; are different
in this document. ...

</BLOCKQUOTE>

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