updating flex?

[Greg Troxel <gdt%ir.bbn.com@localhost>]

Our flex is at 2.5.4, and upstream is now at 2.5.35.  I noticed this
because I was trying to build something that used newer features.  We
have 2.5.35 in pkgsrc.

Does anyone have opinions about whether or not we should upgrade the
in-tree flex to a more recent version?  It seems that we should, absent
some reason why it would be troublesome.

The flex homepage seems to be:

  http://flex.sourceforge.net/