98 lines
3.9 KiB
HTML
98 lines
3.9 KiB
HTML
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<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
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<html>
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<!-- Copyright (C) 1988-2016 Free Software Foundation, Inc.
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Permission is granted to copy, distribute and/or modify this document
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under the terms of the GNU Free Documentation License, Version 1.3 or
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any later version published by the Free Software Foundation; with the
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Invariant Sections being "Funding Free Software", the Front-Cover
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Texts being (a) (see below), and with the Back-Cover Texts being (b)
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(see below). A copy of the license is included in the section entitled
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"GNU Free Documentation License".
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(a) The FSF's Front-Cover Text is:
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A GNU Manual
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(b) The FSF's Back-Cover Text is:
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You have freedom to copy and modify this GNU Manual, like GNU
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software. Copies published by the Free Software Foundation raise
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funds for GNU development. -->
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<!-- Created by GNU Texinfo 5.2, http://www.gnu.org/software/texinfo/ -->
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<head>
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<title>Using the GNU Compiler Collection (GCC): Empty Structures</title>
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<meta name="description" content="Using the GNU Compiler Collection (GCC): Empty Structures">
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<meta name="keywords" content="Using the GNU Compiler Collection (GCC): Empty Structures">
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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<link href="index.html#Top" rel="start" title="Top">
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<link href="Option-Index.html#Option-Index" rel="index" title="Option Index">
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<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
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<link href="C-Extensions.html#C-Extensions" rel="up" title="C Extensions">
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<link href="Variable-Length.html#Variable-Length" rel="next" title="Variable Length">
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<link href="Zero-Length.html#Zero-Length" rel="prev" title="Zero Length">
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<style type="text/css">
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-->
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</style>
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</head>
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<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000">
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<a name="Empty-Structures"></a>
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<div class="header">
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<p>
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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> [<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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</div>
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<hr>
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<a name="Structures-with-No-Members"></a>
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<h3 class="section">6.18 Structures with No Members</h3>
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<a name="index-empty-structures"></a>
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<a name="index-zero_002dsize-structures"></a>
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<p>GCC permits a C structure to have no members:
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</p>
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<div class="smallexample">
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<pre class="smallexample">struct empty {
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};
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</pre></div>
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<p>The structure has size zero. In C++, empty structures are part
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of the language. G++ treats empty structures as if they had a single
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member of type <code>char</code>.
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</p>
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</body>
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</html>
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