Re: [PATCH 09/10] Access buffer_defaults in BVAR if there's no local binding

[Eli Zaretskii]

> From: Stefan Monnier <monnier@iro.umontreal.ca>
> Date: Thu, 19 Nov 2020 13:08:16 -0500
> Cc: Arnold Noronha <arnold@tdrhq.com>, Dmitry Gutov <dgutov@yandex.ru>,
>  emacs-devel@gnu.org
> 
> Your patch series will also presumably slow down BVAR access to the
> other fields since they need to test `SHOULD_USE_BUFFER_DEFAULTS` now,
> but I think this is the price to pay.  It should be negligible for
> accesses to those vars from Elisp code, but of the 600 or so uses of
> BVAR in the current code, I wonder if some of them could show
> a measurable speed penalty.

There are 85 uses of BVAR in xdisp.c, something to look into, I guess.