gentoo-overlay/dev-lang/bas/metadata.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE pkgmetadata SYSTEM "http://www.gentoo.org/dtd/metadata.dtd">
<pkgmetadata>
  <maintainer>
    <email>maintainer-needed@gentoo.org</email>
  </maintainer>
  <use>
    <flag name='lr0'>Use the LR0 parser instead of the recursive descending parser</flag>
  </use>
</pkgmetadata>