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<div class="subsection-level-extent" id="C99-Thread-Local-Edits"> <div class="nav-panel"> <p> Next: <a href="c_002b_002b98-thread-local-edits" accesskey="n" rel="next">ISO/IEC 14882:1998 Edits for Thread-Local Storage</a>, Up: <a href="thread-local" accesskey="u" rel="up">Thread-Local Storage</a> [<a href="index#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="indices" title="Index" rel="index">Index</a>]</p> </div>  <h1 class="subsection" id="ISO_002fIEC-9899_003a1999-Edits-for-Thread-Local-Storage"><span>6.64.1 ISO/IEC 9899:1999 Edits for Thread-Local Storage<a class="copiable-link" href="#ISO_002fIEC-9899_003a1999-Edits-for-Thread-Local-Storage"> ¶</a></span></h1> <p>The following are a set of changes to ISO/IEC 9899:1999 (aka C99) that document the exact semantics of the language extension. </p> <ul class="itemize mark-bullet"> <li>5.1.2 Execution environments <p>Add new text after paragraph 1 </p> <blockquote class="quotation"> <p>Within either execution environment, a <em class="dfn">thread</em> is a flow of control within a program. It is implementation defined whether or not there may be more than one thread associated with a program. It is implementation defined how threads beyond the first are created, the name and type of the function called at thread startup, and how threads may be terminated. However, objects with thread storage duration shall be initialized before thread startup. </p>
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<li>6.2.4 Storage durations of objects <p>Add new text before paragraph 3 </p> <blockquote class="quotation"> <p>An object whose identifier is declared with the storage-class specifier <code class="code">__thread</code> has <em class="dfn">thread storage duration</em>. Its lifetime is the entire execution of the thread, and its stored value is initialized only once, prior to thread startup. </p>
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<li>6.4.1 Keywords <p>Add <code class="code">__thread</code>. </p> </li>
<li>6.7.1 Storage-class specifiers <p>Add <code class="code">__thread</code> to the list of storage class specifiers in paragraph 1. </p> <p>Change paragraph 2 to </p> <blockquote class="quotation"> <p>With the exception of <code class="code">__thread</code>, at most one storage-class specifier may be given […]. The <code class="code">__thread</code> specifier may be used alone, or immediately following <code class="code">extern</code> or <code class="code">static</code>. </p>
</blockquote> <p>Add new text after paragraph 6 </p> <blockquote class="quotation"> <p>The declaration of an identifier for a variable that has block scope that specifies <code class="code">__thread</code> shall also specify either <code class="code">extern</code> or <code class="code">static</code>. </p> <p>The <code class="code">__thread</code> specifier shall be used only with variables. </p>
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</ul> </div>  <div class="nav-panel"> <p> Next: <a href="c_002b_002b98-thread-local-edits">ISO/IEC 14882:1998 Edits for Thread-Local Storage</a>, Up: <a href="thread-local">Thread-Local Storage</a> [<a href="index#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="indices" title="Index" rel="index">Index</a>]</p> </div><div class="_attribution">
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