Re: [PATCH] Interferences between xwidgets and async processes?

[JIANG Shaojian]

Hi,

WIth previous patch, I just noticed a message generated by xwidget saying "Overriding existing handler for signal 10. Set JSC_SIGNAL_FOR_GC if you want WebKit to use a different signal".

I did a bit of search and found out that this might be related to a recent version of libwebkit2gtk (see a similar message in https://github.com/vertcoin-project/one-click-miner-vnext/issues/271).

The current version of the library on my ubuntu is 2.32. I tried to downgrade it to an earlier version available, which is 2.28 and the issue is gone. 

So it seems that the updated library breaks previous fix.

Further debugging is beyond my expertise. Hopefully the above information is useful.

Thanks.

JIANG Shaojian <sdycjsj@gmail.com> 于2021年7月30日周五 上午10:55写道：

Hi, 

I just built emacs 28 with the lasted source, and it seems that this bug reappears.

Since I have not updated emacs for a long time, I am not sure when it came back.

I checked xwidget.c and previous fix is still there.

The testing environment and the way to reproduce it is the same as before.

Hopefully someone can confirm this. 

Thanks!

Akira Kyle <ak@akirakyle.com> 于2020年11月15日周日 上午3:53写道：

On Sat, Nov 14, 2020 at 09:22 AM, Eli Zaretskii <eliz@gnu.org>
wrote:

>> > The attached patch fixes this but only in a temporary way.
>>
>> Thanks; applied to Emacs 28.
>
> Just to be sure: the fix that is now installed on master does
> support
> current and old versions of Glib, where the old code seemed to
> work?
> Or does it break with older Glib versions?

I didn't explicitly try it with glib versions before they changed
the signal handling in commit 2e471acf, but it *should* work with
versions before the change. As you can see in the patch, it
essentially just makes Emacs more aggressive in taking over the
signal handler and in glib versions before 2e471acf,
g_source_unref (source) wouldn't result in glib resetting the
signal handler to SIG_DFL, in which case Emacs will just install
itself twice to handle SIGCHLD which is fine.

I think commit 2e471acf got added to glib with version 2.37.5
which was released over 7 years ago.