bug#60308: 30.0.50; Can't read some PDF files any more

[Eli Zaretskii]

> Date: Thu, 05 Jan 2023 20:58:24 +0000
> From: Gregory Heytings <gregory@heytings.org>
> cc: Ihor Radchenko <yantar92@posteo.net>, 60308@debbugs.gnu.org, 
>     bugs@gnu.support
> 
> >>> I can't read this file with emacs -Q:
> >>>
> >>> https://gnu.support/files/tmp/2023-01-05/FR%20205.pdf
> >>
> >> I can reproduce on Emacs 30 and Emacs 29, but not on Emacs 28
> >>
> >> Recipe: emacs -Q /path/to/the/linked/downloaded/pdf
> >>
> >> Observed: empty buffer
> >> Expected: PDF page is displayed
> >
> > Can someone bisect this, please?
> >
> 
> FTR, that file opens fine here, with Emacs 29 at ec172d748f, at 
> d2a9dae400, at a6bad4d60f, at c59b8dfefa... and with Emacs 28.

Thanks.

So maybe the problem is updates to libraries/executables we use for
viewing PDF?  AFAIR, this is DocView, and it use Ghostscript and
libpng?  Maybe both Jean and Ihor had their systems updated recently?