bug#69431: 30.0.50; Strange fontificaion behavior

[Andrea Corallo]

Eli Zaretskii <eliz@gnu.org> writes:

> Ping!  Björn, could you please try what Andrea asked you?  I'd like to
> make progress with this bug report.
>
>> From: Andrea Corallo <acorallo@gnu.org>
>> Cc: 69431@debbugs.gnu.org,  Ihor Radchenko <yantar92@posteo.net>,  Eli
>>  Zaretskii <eliz@gnu.org>
>> Date: Thu, 07 Mar 2024 17:33:14 -0500
>> 
>> Andrea Corallo <acorallo@gnu.org> writes:
>> 
>> > OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> writes:
>> >
>> >> Andrea Corallo <acorallo@gnu.org> writes:
>> >>
>> >>> Ihor Radchenko <yantar92@posteo.net> writes:
>> >>>
>> >>>> Eli Zaretskii <eliz@gnu.org> writes:
>> >>>>
>> >>>>>> I cannot reproduce when changing the load path to Org git
>> >>>>>> folder ( main, bugfix branches, and Org 9.6.15 tag which should be the
>> >>>>>> same with Emacs built-in version).
>> >>>>>
>> >>>>> So maybe the problem is already solved somehow?
>> >>>>
>> >>>> ... or it has something to do with loading built-in Org mode.
>> >>>> when I do
>> >>>> 1. emacs -Q
>> >>>> 2. C-x C-f /tmp/a.org
>> >>>> I do not see fontification.
>> >>>
>> >>> On 415604c7a77 (current master) I'm having trouble reproducing this.
>> >>> Both with the eln cache empty both with it already warmed.
>> >>>
>> >>> Is this just local on my machine or the bug vanished? 🤔
>> >>
>> >> I'm still able to reproduce this on 415604c7a77.
>> >>
>> >>     $ emacs -Q a.org
>> >
>> > Okay I can reproduce it using Emacs with GUI and not on terminal.
>> 
>> Okay I've spent some time investigating, on my setup I can reproduce
>> this on GUI *only* when the eln-cache is empty with the suggested $ emacs -Q 
>> foo.org
>> 
>> I can't reproduce configuring with --with-native-compilation=aot
>> 
>> I can't reproduce with $ emacs -Q -eval "(setq native-comp-jit-compilation 
>> nil)" foo.org
>> 
>> These observations would suggest is native compilation related.
>> 
>> I can't see any SIGEGV in gdb in all of these tests.
>> 
>> Also as Ihor suggested (thanks!) reverting cf11fdfd8e46 makes issue not
>> reproducible here, but I still have to understand the reason (maybe some
>> circular dependency??).
>> 
>> Meanwhile Björn could you try reverting cf11fdfd8e46 and report if fixes
>> for you as well?

I'm trying to progress on this but I've difficult time at getting a grip
on this bug.  One of the reason why is that on my reproducer Emacs
doesn't crash nor complain, the other reason is that I'm not really into
our fontification.  I'll keep on looking into it but I'd appretiate any
hint like: what should be happening to fontify the buffer that is not
actually happening here?  With such info I could try investingating the
issue from there comparing with the working case.

Thanks in advance!

  Andrea