<li>gl_ClipVertex
<li>The derivative functions such as dFdx() are not implemented
<li>The inverse trig functions asin(), acos(), and atan() are not implemented
+<li>The gl_Color and gl_SecondaryColor varying vars are interpolated
+ without perspective correction
+<li>Floating point literal suffixes 'f' and 'F' aren't allowed.
</ul>
<p>