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<title>Using the GNU Compiler Collection (GCC): Empty Structures</title>
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<a name="Empty-Structures"></a>
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Next: <a href="Variable-Length.html#Variable-Length" accesskey="n" rel="next">Variable Length</a>, Previous: <a href="Zero-Length.html#Zero-Length" accesskey="p" rel="prev">Zero Length</a>, Up: <a href="C-Extensions.html#C-Extensions" accesskey="u" rel="up">C Extensions</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Structures-With-No-Members"></a>
<h3 class="section">6.18 Structures With No Members</h3>
<a name="index-empty-structures"></a>
<a name="index-zero_002dsize-structures"></a>
<p>GCC permits a C structure to have no members:
</p>
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<pre class="smallexample">struct empty {
};
</pre></div>
<p>The structure has size zero. In C++, empty structures are part
of the language. G++ treats empty structures as if they had a single
member of type <code>char</code>.
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