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<title>GNU Compiler Collection (GCC) Internals: Language-dependent trees</title>

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Next: <a href="C-and-C_002b_002b-Trees.html#C-and-C_002b_002b-Trees" accesskey="n" rel="next">C and C++ Trees</a>, Previous: <a href="Functions.html#Functions" accesskey="p" rel="prev">Functions</a>, Up: <a href="GENERIC.html#GENERIC" accesskey="u" rel="up">GENERIC</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Language_002ddependent-trees-1"></a>
<h3 class="section">10.9 Language-dependent trees</h3>
<a name="index-language_002ddependent-trees"></a>

<p>Front ends may wish to keep some state associated with various GENERIC
trees while parsing.  To support this, trees provide a set of flags
that may be used by the front end.  They are accessed using
<code>TREE_LANG_FLAG_n</code> where &lsquo;<samp>n</samp>&rsquo; is currently 0 through 6.
</p>
<p>If necessary, a front end can use some language-dependent tree
codes in its GENERIC representation, so long as it provides a
hook for converting them to GIMPLE and doesn&rsquo;t expect them to
work with any (hypothetical) optimizers that run before the
conversion to GIMPLE. The intermediate representation used while
parsing C and C++ looks very little like GENERIC, but the C and
C++ gimplifier hooks are perfectly happy to take it as input and
spit out GIMPLE.
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