Hi,

First of all, thanks a lot for actively developing and maintaining Emacs.
It is something that makes me very happy in my daily work.

Some time ago I found a bug in vhdl-mode.el after trying to extract the
hierarchy in speedbar of the current design. The design I'm trying to parse
is the one based on the following repo:
- https://github.com/gmlarumbe/axi_if_converter

After opening the following file (*src/top/rtl/axi_if_converter.vhd*),
starting speedbar and pressing 'h' to get the hierarchy I get the following
error:
- WARNING:  ERROR:  Invalid hierarchy information, unable to display
correctly

When I first debugged this issue some time ago it seemed it had to do with
lexical-binding and the function `vhdl-speedbar-insert-hierarchy`. I made
some changes that made it work and could help debugging in a branch of my
emacs-mirror fork:
https://github.com/emacs-mirror/emacs/compare/master...gmlarumbe:emacs:vhdl-projects

Yesterday I also checked that vhdl-mode has received some updates since
then, some of them in this particular `vhdl-speedbar-insert-hierarchy`
function that actually had to do with lexical-binding (commit a769cbfcfb by
Eli Zaretskii). I made some new simple changes that I attach in a diff file
and seem to fix the issue. However, maybe the author/maintainer knows a
better way of fixing this.

Thanks a lot for your effort,

Best,

Gonzalo