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<h2 class="chapter">10 Traditional Mode</h2>
<p>Traditional (pre-standard) C preprocessing is rather different from
the preprocessing specified by the standard. When GCC is given the
<samp><span class="option">-traditional-cpp</span></samp> option, it attempts to emulate a traditional
preprocessor.
<p>GCC versions 3.2 and later only support traditional mode semantics in
the preprocessor, and not in the compiler front ends. This chapter
outlines the traditional preprocessor semantics we implemented.
<p>The implementation does not correspond precisely to the behavior of
earlier versions of GCC, nor to any true traditional preprocessor.
After all, inconsistencies among traditional implementations were a
major motivation for C standardization. However, we intend that it
should be compatible with true traditional preprocessors in all ways
that actually matter.
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<li><a accesskey="1" href="Traditional-lexical-analysis.html#Traditional-lexical-analysis">Traditional lexical analysis</a>
<li><a accesskey="2" href="Traditional-macros.html#Traditional-macros">Traditional macros</a>
<li><a accesskey="3" href="Traditional-miscellany.html#Traditional-miscellany">Traditional miscellany</a>
<li><a accesskey="4" href="Traditional-warnings.html#Traditional-warnings">Traditional warnings</a>
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