Re: Lexical binding doesn't seem to be faster?

[Hi-Angel <hiangel999@gmail.com>]

On Sun, 10 Mar 2019 at 21:59, Stefan Monnier <monnier@iro.umontreal.ca> wrote:
>
> > If you say "several seconds enough", then it's already there, the
> > benchmark with GC enabled takes 9 seconds.
>
> Hmm... then there's a problem with the sampling.  Is this in a batch
> Emacs session?  What OS?  I think this might deserve its own bug report.

It's `emacs -Q` ran one time. Archlinux here, but Emacs is not from a
repository, but a ≈month old version from git.

Something similar can be reproduced in 2 steps:

    1. wget https://gitlab.freedesktop.org/libinput/libinput/raw/9a2d6f55b1276da11dd9b2c4c8e22a405576dfea/src/libinput.h
    2. emacs -Q --eval "(progn (find-file \"./libinput.h\")
(profiler-start 'cpu) (benchmark-run-compiled 10
(c-font-lock-fontify-region 0 (point-max))) (profiler-report))"

Since by default cc-mode.el doesn't use lexical-binding, you should
get this result:
    - ...           1 100%
       Automatic GC 1 100%

Do you want me to open a report for above?