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94 lines
3.9 KiB
HTML
94 lines
3.9 KiB
HTML
<!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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Permission is granted to copy, distribute and/or modify this document
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any later version published by the Free Software Foundation; with the
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A GNU Manual
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<head>
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<title>Empty Statements (GNU Compiler Collection (GCC) Internals)</title>
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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="Statements.html#Statements" rel="up" title="Statements">
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<link href="Jumps.html#Jumps" rel="next" title="Jumps">
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<link href="Statement-Sequences.html#Statement-Sequences" rel="prev" title="Statement Sequences">
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<a name="Empty-Statements"></a>
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<div class="header">
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<p>
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Next: <a href="Jumps.html#Jumps" accesskey="n" rel="next">Jumps</a>, Previous: <a href="Statement-Sequences.html#Statement-Sequences" accesskey="p" rel="prev">Statement Sequences</a>, Up: <a href="Statements.html#Statements" accesskey="u" rel="up">Statements</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="Empty-Statements-1"></a>
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<h4 class="subsection">11.7.4 Empty Statements</h4>
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<a name="index-Empty-Statements"></a>
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<p>Whenever possible, statements with no effect are discarded. But
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if they are nested within another construct which cannot be
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discarded for some reason, they are instead replaced with an
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empty statement, generated by <code>build_empty_stmt</code>.
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Initially, all empty statements were shared, after the pattern of
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the Java front end, but this caused a lot of trouble in practice.
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</p>
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<p>An empty statement is represented as <code>(void)0</code>.
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</p>
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