Re: [PATCH 0/7] Cleanups and tests for DEFVAR_PER_BUFFER variables

[Eli Zaretskii <eliz@gnu.org>]

> From: Spencer Baugh <sbaugh@catern.com>
> Date: Tue, 23 Mar 2021 23:11:50 -0400
> Cc: Spencer Baugh <sbaugh@catern.com>, Eli Zaretskii <eliz@gnu.org>,
>  Stefan Monnier <monnier@iro.umontreal.ca>
> 
> Hi emacs-devel,

Actually, it is best to send this (and patches in general) to
bug-gnu-emacs@gnu.org, so that the whole discussion is recorded by our
issue tracker.

> These are some cleanups and tests for DEFVAR_PER_BUFFER variables.
> I think they are all uncontroversial.
> 
> These are extracted from the patch series I sent some months ago
> (Subject: Speeding up DEFVAR_PER_BUFFER).  Specifically, these are the
> patches that were approved as fine independent of the rest of the
> series.  And they have changelog entries in the commit messages now :)
> 
> These are pre-requisites for my DEFVAR_PER_BUFFER improvements (which
> I'll be resending soon), so it would be nice to apply them ahead of
> that.

I'd prefer to pick up where we left off back then.  The main issue
left unresolved in the past discussion was the potential slowdown of
simple accesses to buffer-local vars due to your proposal.  Can we
please have benchmarks for that, so we could decide whether the
tradeoff is worth it?  It's quite possible that the performance
aspects could affect the code changes, so even uncontroversial
cleanups should perhaps wait until we have figured out the more
important aspects of these changesets.

Thanks.