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<title>Issue 314: Is the stack unwound when terminate() is called?</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="314"><a href="lwg-closed.html#314">314</a>. Is the stack unwound when terminate() is called?</h3>
<p><b>Section:</b> 17.9.5.4 <a href="https://wg21.link/terminate">[terminate]</a> <b>Status:</b> <a href="lwg-active.html#NAD">NAD</a>
 <b>Submitter:</b> Detlef Vollmann <b>Opened:</b> 2001-04-11 <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#terminate">issues</a> in [terminate].</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 standard appears to contradict itself about whether the stack is
unwound when the implementation calls terminate().
</p>

<p>From 18.7.3.3p2:</p>
<blockquote><p>
    Calls the terminate_handler function in effect immediately
    after evaluating the throw-expression (lib.terminate.handler),
    if called by the implementation [...]
</p></blockquote>

<p>So the stack is guaranteed not to be unwound.</p>

<p>But from 15.3p9:</p>
<blockquote><p>
    [...]whether or not the stack is unwound before this call
    to terminate() is implementation-defined (except.terminate).
</p></blockquote>

<p>
And 15.5.1 actually defines that in most cases the stack is unwound.
</p>


<p id="res-314"><b>Proposed resolution:</b></p>


<p><b>Rationale:</b></p>
<p>There is definitely no contradiction between the core and library
clauses; nothing in the core clauses says that stack unwinding happens
after <code>terminate</code> is called.  18.7.3.3p2 does not say anything
about when terminate() is called; it merely specifies which
<code>terminate_handler</code> is used.</p>





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