Looking at the fix, Donald has only removed IPV4_CLASS_DE(a) ((((uint32_t)(a)) & 0xe0000000) == 0xe0000000)
validation but kept INADDR_ANY. 
I’ll bring up RFC6286 to him

Cheers,
Jeff

On Sep 12, 2022, at 13:41, Bjørn Mork <bjorn@mork.no> wrote:

Jeff Tantsura <jefftant.ietf@gmail.com> writes:

Indeed, someone was recently complaining that FRR is unhappy with a
peer with router-id from class E range…

This made me curious enough to dig up the fix.  If anyone else is interested:
https://github.com/FRRouting/frr/commit/b5c2113e47f846d0c48fb4ef63e29bf96bd2fbe2


Bjørn