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  68. <h4 class="subsection">11.7.4 Empty Statements</h4>
  69. <a name="index-Empty-Statements"></a>
  70. <p>Whenever possible, statements with no effect are discarded. But
  71. if they are nested within another construct which cannot be
  72. discarded for some reason, they are instead replaced with an
  73. empty statement, generated by <code>build_empty_stmt</code>.
  74. Initially, all empty statements were shared, after the pattern of
  75. the Java front end, but this caused a lot of trouble in practice.
  76. </p>
  77. <p>An empty statement is represented as <code>(void)0</code>.
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