105 lines
4.4 KiB
HTML
105 lines
4.4 KiB
HTML
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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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Invariant Sections being "Funding Free Software", the Front-Cover
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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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<!-- 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): Weak Pragmas</title>
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<meta name="description" content="Using the GNU Compiler Collection (GCC): Weak Pragmas">
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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="Pragmas.html#Pragmas" rel="up" title="Pragmas">
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<link href="Diagnostic-Pragmas.html#Diagnostic-Pragmas" rel="next" title="Diagnostic Pragmas">
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<link href="Structure_002dLayout-Pragmas.html#Structure_002dLayout-Pragmas" rel="prev" title="Structure-Layout Pragmas">
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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="Weak-Pragmas"></a>
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<div class="header">
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<p>
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Next: <a href="Diagnostic-Pragmas.html#Diagnostic-Pragmas" accesskey="n" rel="next">Diagnostic Pragmas</a>, Previous: <a href="Structure_002dLayout-Pragmas.html#Structure_002dLayout-Pragmas" accesskey="p" rel="prev">Structure-Layout Pragmas</a>, Up: <a href="Pragmas.html#Pragmas" accesskey="u" rel="up">Pragmas</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="Weak-Pragmas-1"></a>
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<h4 class="subsection">6.61.11 Weak Pragmas</h4>
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<p>For compatibility with SVR4, GCC supports a set of <code>#pragma</code>
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directives for declaring symbols to be weak, and defining weak
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aliases.
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</p>
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<dl compact="compact">
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<dt><code>#pragma weak <var>symbol</var></code></dt>
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<dd><a name="index-pragma_002c-weak"></a>
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<p>This pragma declares <var>symbol</var> to be weak, as if the declaration
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had the attribute of the same name. The pragma may appear before
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or after the declaration of <var>symbol</var>. It is not an error for
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<var>symbol</var> to never be defined at all.
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</p>
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</dd>
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<dt><code>#pragma weak <var>symbol1</var> = <var>symbol2</var></code></dt>
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<dd><p>This pragma declares <var>symbol1</var> to be a weak alias of <var>symbol2</var>.
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It is an error if <var>symbol2</var> is not defined in the current
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translation unit.
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</p></dd>
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</dl>
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</body>
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</html>
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