105 lines
4.4 KiB
HTML
105 lines
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HTML
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<title>Using the GNU Compiler Collection (GCC): Weak Pragmas</title>
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<link href="Pragmas.html#Pragmas" rel="up" title="Pragmas">
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<a name="Weak-Pragmas"></a>
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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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<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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