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<title>Issue 3784: std.compat should not provide ::byte and its friends</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++23">C++23</a> status.</em></p>
<h3 id="3784"><a href="lwg-defects.html#3784">3784</a>. <code>std.compat</code> should not provide <code>::byte</code> and its friends</h3>
<p><b>Section:</b> 16.4.2.4 <a href="https://wg21.link/std.modules">[std.modules]</a> <b>Status:</b> <a href="lwg-active.html#C++23">C++23</a>
 <b>Submitter:</b> Jiang An <b>Opened:</b> 2022-09-19 <b>Last modified:</b> 2023-11-22</p>
<p><b>Priority: </b>Not Prioritized
</p>
<p><b>View all issues with</b> <a href="lwg-status.html#C++23">C++23</a> status.</p>
<p><b>Discussion:</b></p>
<p>
Currently 16.4.2.4 <a href="https://wg21.link/std.modules">[std.modules]</a>/3 seemly requires that the <code>std.compat</code> module 
has to provide <code>byte</code> (via <code>&lt;cstddef&gt;</code>), <code>beta</code> (via <code>&lt;cmath&gt;</code>) 
etc. in the global namespace, which is defective to me as these components are C++-only, 
and doing so would increase the risk of conflict.
<p/>
I think we should only let <code>std.compat</code> provide the same set of global declarations as 
<code>&lt;xxx.h&gt;</code> headers.
</p>

<p><i>[2022-10-12; Reflector poll]</i></p>

<p>
Set status to Tentatively Ready after nine votes in favour during reflector poll.
</p>

<p><i>[2022-11-12 Approved at November 2022 meeting in Kona. Status changed: Voting &rarr; WP.]</i></p>



<p id="res-3784"><b>Proposed resolution:</b></p>
<p>
This wording is relative to <a href="https://wg21.link/N4917" title=" Working Draft, Standard for Programming Language C++">N4917</a>.
</p>

<ol>

<li><p>Modify 16.4.2.4 <a href="https://wg21.link/std.modules">[std.modules]</a> as indicated:</p>

<blockquote>
<p>
-3- The named module <code>std.compat</code> exports the same declarations as the named module <code>std</code>, 
and additionally exports declarations in the global namespace corresponding to the declarations in 
namespace <code>std</code> that are provided by the C++ headers for C library facilities 
(Table 26)<ins>, except the explicitly excluded declarations described in 17.15.7 <a href="https://wg21.link/support.c.headers.other">[support.c.headers.other]</a></ins>.
</p>
</blockquote>
</li>

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