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<h4 class="subsection">11.7.4 Empty Statements</h4>
<a name="index-Empty-Statements"></a>

<p>Whenever possible, statements with no effect are discarded.  But
if they are nested within another construct which cannot be
discarded for some reason, they are instead replaced with an
empty statement, generated by <code>build_empty_stmt</code>.
Initially, all empty statements were shared, after the pattern of
the Java front end, but this caused a lot of trouble in practice.
</p>
<p>An empty statement is represented as <code>(void)0</code>.
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