 These elements
are specified like <a href="../using.html#arg">Command-line
Arguments</a> but have an additional attribute that can be used to
enable arguments only if a given compiler implementation will be
used.</p>
<table border="1" cellpadding="2" cellspacing="0">
<tr>
  <td width="12%" valign="top"><b>Attribute</b></td>
  <td width="78%" valign="top"><b>Description</b></td>
  <td width="10%" valign="top"><b>Required</b></td>
</tr>
  <tr>
    <td valign="top">value</td>
    <td align="center" rowspan="4