** https://www.gnu.org/software/libtool/[GNU Libtool]{nbsp}≥{nbsp}2.2
** https://github.com/westes/flex[flex]{nbsp}≥{nbsp}2.5.35
** https://www.gnu.org/software/bison/bison.html[GNU Bison]{nbsp}≥{nbsp}2.4
** https://www.gnu.org/software/libtool/[GNU Libtool]{nbsp}≥{nbsp}2.2
** https://github.com/westes/flex[flex]{nbsp}≥{nbsp}2.5.35
** https://www.gnu.org/software/bison/bison.html[GNU Bison]{nbsp}≥{nbsp}2.4