On Linux systems, flex and bison versions 2.5.35 and 2.4.1, respectively,
(or later) should work.
On Windows with MinGW, install flex and bison with:
+</p>
<pre>mingw-get install msys-flex msys-bison</pre>
+<p>
For MSVC on Windows, install
<a href="http://winflexbison.sourceforge.net/">Win flex-bison</a>.
</p>