Subject: bug#70796: 30.0.50; bug-reference-mode leading to constant GCing

From: Andrea Corallo <[email-masked]>
Date: Mon, 17 Jun 2024 04:07:55 -0400

Andrea Corallo <[email-masked]> writes:

> Eli Zaretskii <[email-masked]> writes:
>
>>> From: Tassilo Horn <[email-masked]>
>>> Cc: Eli Zaretskii <[email-masked]>,  [email-masked],  [email-masked]
>>> Date: Sun, 16 Jun 2024 11:45:16 +0200
>>> 
>>> Gerd Möllmann <[email-masked]> writes:
>>> 
>>> > No progress in this matter from my side. I don't know what's going on.
>>> 
>>> Same here.  The issue went from "bug-reference-mode leading to constant
>>> GC-ing" to "any (additional) function (including a no-op function) in
>>> jit-lock-functions leads to constant GC-ing on MacOS but only with
>>> native compilation and only when native-comp-speed > 0."  I feel
>>> responsible for bug-reference-mode but Mac-specific issues during
>>> redisplay that only happen with native-compilation are out of by
>>> expertise, sorry.
>>
>> Andrea, could you perhaps look into this?
>
> I'll be happy to look into it but I don't use MacOS and AFAIR Tassilo
> mentioned it's not reproducible on x86 (GNU/Linux?).
>
> I'll give it try here as well, but also to me the reproducer itself is
> not 100% clear.
>
>   Andrea

Okay, so this is what I tried:

I bootstrapped two Emacs from current master (7be66d8223e) one
--with-native-compilation=yes the other --with-native-compilation=no and
boths with Gerd patch applied.

Also I checkout current scratch/igc (2343d55dff4) to get igc.org.

I then tried to run with boths native/non-native emacsen with:

.../src/emacs -eval '(setq garbage-collection-messages t)' -Q ~/emacs4/admin/igc.org

Once started looking in *Messages* I see 7 GC cycles in the the
non-native build and 5 in the native one, also I can scroll without
issues or other GC cycles.

Note that only during the first start the native copiled Emacs did a
number of GC cycles more to jit some code but I guess that's expected.

Am I trying to repruduce this correctly?

Thanks

  Andrea