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

From: Mattias Engdegård <[email-masked]>
Date: Mon, 11 Sep 2023 18:21:55 +0200

> 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.