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  68. <h4 class="subsection">11.10.6 C++ Expressions</h4>
  69. <p>This section describes expressions specific to the C and C++ front
  70. ends.
  71. </p>
  72. <dl compact="compact">
  73. <dt><code>TYPEID_EXPR</code></dt>
  74. <dd>
  75. <p>Used to represent a <code>typeid</code> expression.
  76. </p>
  77. </dd>
  78. <dt><code>NEW_EXPR</code></dt>
  79. <dt><code>VEC_NEW_EXPR</code></dt>
  80. <dd>
  81. <p>Used to represent a call to <code>new</code> and <code>new[]</code> respectively.
  82. </p>
  83. </dd>
  84. <dt><code>DELETE_EXPR</code></dt>
  85. <dt><code>VEC_DELETE_EXPR</code></dt>
  86. <dd>
  87. <p>Used to represent a call to <code>delete</code> and <code>delete[]</code> respectively.
  88. </p>
  89. </dd>
  90. <dt><code>MEMBER_REF</code></dt>
  91. <dd>
  92. <p>Represents a reference to a member of a class.
  93. </p>
  94. </dd>
  95. <dt><code>THROW_EXPR</code></dt>
  96. <dd>
  97. <p>Represents an instance of <code>throw</code> in the program. Operand 0,
  98. which is the expression to throw, may be <code>NULL_TREE</code>.
  99. </p>
  100. </dd>
  101. <dt><code>AGGR_INIT_EXPR</code></dt>
  102. <dd><p>An <code>AGGR_INIT_EXPR</code> represents the initialization as the return
  103. value of a function call, or as the result of a constructor. An
  104. <code>AGGR_INIT_EXPR</code> will only appear as a full-expression, or as the
  105. second operand of a <code>TARGET_EXPR</code>. <code>AGGR_INIT_EXPR</code>s have
  106. a representation similar to that of <code>CALL_EXPR</code>s. You can use
  107. the <code>AGGR_INIT_EXPR_FN</code> and <code>AGGR_INIT_EXPR_ARG</code> macros to access
  108. the function to call and the arguments to pass.
  109. </p>
  110. <p>If <code>AGGR_INIT_VIA_CTOR_P</code> holds of the <code>AGGR_INIT_EXPR</code>, then
  111. the initialization is via a constructor call. The address of the
  112. <code>AGGR_INIT_EXPR_SLOT</code> operand, which is always a <code>VAR_DECL</code>,
  113. is taken, and this value replaces the first argument in the argument
  114. list.
  115. </p>
  116. <p>In either case, the expression is void.
  117. </p>
  118. </dd>
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