Packages with the re2 use flag

app-misc / sphinx : Full-text search engine with support for MySQL and PostgreSQL

  • use the dev-libs/re2 regular expression library

net-analyzer / mk-livestatus : Nagios/Icinga event broker that allows quick/direct access to your status data

  • Use dev-libs/re2 for regex support

net-irc / inspircd : Inspire IRCd - The Stable, High-Performance Modular IRCd

  • Add support for Google RE2 regular expressions library