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<title>Issue 2888: Variables of library tag types need to be inline variables</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#Resolved">Resolved</a> status.</em></p>
<h3 id="2888"><a href="lwg-defects.html#2888">2888</a>. Variables of library tag types need to be inline variables</h3>
<p><b>Section:</b> 22 <a href="https://wg21.link/utilities">[utilities]</a>, 32 <a href="https://wg21.link/thread">[thread]</a> <b>Status:</b> <a href="lwg-active.html#Resolved">Resolved</a>
 <b>Submitter:</b> Finland <b>Opened:</b> 2017-02-03 <b>Last modified:</b> 2017-03-20</p>
<p><b>Priority: </b>Not Prioritized
</p>
<p><b>View all other</b> <a href="lwg-index.html#utilities">issues</a> in [utilities].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#Resolved">Resolved</a> status.</p>
<p><b>Discussion:</b></p>
<b>Addresses FI 9</b>

<p>The variables of library tag types need to be inline variables. Otherwise, using them in inline functions in multiple 
translation units is an ODR violation.</p>
<p>Proposed change: Make <code>piecewise_construct</code>, <code>allocator_arg</code>, <code>nullopt</code>, (the <code>in_place_tags</code> 
after they are made regular tags), <code>defer_lock</code>, <code>try_to_lock</code> and <code>adopt_lock</code> inline.</p>

<p><i>[2017-02-03, Marshall notes]</i></p>

<p>See also GB 28 (LWG <a href="lwg-defects.html#2889" title="Mark constexpr global variables as inline (Status: Resolved)">2889</a><sup><a href="https://cplusplus.github.io/LWG/issue2889" title="Latest snapshot">(i)</a></sup>)</p>

<p><i>[2017-02-25, Daniel comments]</i></p>

<p>
There will be the paper p0607r0 provided for the Kona meeting that solves this issue.
</p>
<p><i>[2017-03-12, post-Kona]</i></p>

<p>Resolved by p0607r0.</p>


<p id="res-2888"><b>Proposed resolution:</b></p>





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