bug#65464: Emacs 29.1 - VHDL mode missing updates…

[Mattias Engdegård]

> Does this mean the answer to Reto's question is "yes, it's a known problem 
> for which we have no solution"?

That's right, assuming the question was about packages that were byte-compiled 
on newer Emacs versions than they are used on. Changes to Emacs are usually 
backward-compatible with respect to .elc files, but there is never guarantee 
that they are forward-compatible.

This is not just a matter of changes to the byte-code compiler and interpreter 
but more often about changes to macros.

In other words, if someone is unable to run vhdl-mode.elc from Emacs 29 on 
Emacs 28, then we're very sorry but do not consider it a defect that needs to 
be remedied.