[Pkg-kde-extras] Bug#1034310: [digikam] [Bug 466170] Digikam 7.9.0 (and 7.8.0) crashes on startup

[Rainer Dorsch]

Hi Steve,

Am Sonntag, 16. April 2023, 00:27:46 CEST schrieben Sie:
> 
> Hello Rainer,
> 
> I've looked at the upstream bug, and all the information you provided. 
> That's awesome -- I wish that every bug submitter would be as thorough as
> you!

It was not difficult and did not take a lot of time. But I can imagine that with 
such a popular package as digikam, there are many uses w/o any packaging or 
development experience.

> It seems that, even with disabling the splash screen, you still experience
> the bug -- is that correct?

With splash screen disabled, I don't see it anymore ;-).

> I can say that I'm not experiencing any such crash.  I created a new user to
> test from scratch.  I see the splash screen come and go, then the pop-up
> that offers to download the faces data files.  I can download them or not
> and it all works fine either way.
> 
> So it's puzzling.  I'm also using an x64 system, but I run on the "sid/
> unstable" distribution so I have slightly different versions of the
> dependency packages.   Maybe it's worth attempting an upgrade of some or
> all of these to see if the problem goes away?

Let me elaborate a somewhat:

The spash screen bug I found is visible in the backtrace in comment 5:

https://bugs.kde.org/show_bug.cgi?id=466170#c5

According to Maik, the bug is triggered by a race condition (comment 6). I.e. 
even with exact the same software configuration, there is a good chance that 
you don't see it, because the timing on your hardware might be different 
(different CPU, memory latencies, cache configurations,....). In particular if 
it is hard to hit the race condition, as it seems to be the case.

In comment 9

https://bugs.kde.org/show_bug.cgi?id=466170#c9

Maik provided a fix for the splash screen issue.

I see to good options to handle this:

Either check if the commit also applies to 7.9, I would think there is a good 
chance for this.  I can help and build 7.9 on my system with the commit. Do 
you know a good way to generate a patch for debian/patches out of the commit 
above? And if yes, would it be sufficient to add it to debian/patches/series 
before building?

Or since splash screen is not a key feature, disable splash screen in the 
default config and tell the users who upgrade that disabling splash screen 
would be a workaround for this issue. At least some packages notify users on 
important changes before the upgrade.


But the more important issue is the crash which I see after disabling splash 
screen. The backtrace is provided in comment 7

https://bugs.kde.org/show_bug.cgi?id=466170#c7

Here Maik thinks it is a Debian problem, related to QtWebEngine.


> Perhaps start with libkf5configcore5, since the failing assert seems to be
> in that library:
> 
> 	qt_assert_x(char const*, char const*, char const*, int) () at /lib/
> x86_64-linux-gnu/libQt5Core.so.5

Looking at the changes that is likely a red herring:

https://tracker.debian.org/news/1427674/accepted-kconfig-51030-2-source-into-unstable/

I am on Xorg, are you using Wayland?

> Here is the list from my system today.
> 
> Versions of packages digikam depends on:
> ii  digikam-data          4:7.9.0-1
> ii  digikam-private-libs  4:7.9.0-1+b2
> ii  libc6                 2.36-9
> ii  libgcc-s1             12.2.0-14
> ii  libkf5configcore5     5.103.0-2
> ii  libkf5coreaddons5     5.103.0-1
> ii  libkf5i18n5           5.103.0-1
> ii  libmagick++-6.q16-8   8:6.9.11.60+dfsg-1.6
> ii  libqt5core5a          5.15.8+dfsg-7
> ii  libqt5gui5            5.15.8+dfsg-7
> ii  libqt5sql5            5.15.8+dfsg-7
> ii  libqt5sql5-mysql      5.15.8+dfsg-7
> ii  libqt5sql5-sqlite     5.15.8+dfsg-7
> ii  libqt5widgets5        5.15.8+dfsg-7
> ii  libstdc++6            12.2.0-14
> ii  perl                  5.36.0-7
> 
> Versions of packages digikam recommends:
> ii  brave-browser [www-browser]         1.50.119
> ii  ffmpegthumbs                        4:22.12.3-1
> ii  firefox-esr [www-browser]           102.10.0esr-1
> ii  google-chrome-stable [www-browser]  112.0.5615.121-1
> ii  konqueror [www-browser]             4:22.12.3-1
> ii  lynx [www-browser]                  2.9.0dev.12-1
> ii  w3m [www-browser]                   0.5.3+git20230121-2
> 
> Versions of packages digikam suggests:
> ii  breeze-icon-theme  4:5.103.0-1
> pn  digikam-doc        <none>
> ii  systemsettings     4:5.27.2-1

How do you generate this list?

Do you know if I can disable the faces download? I am not using faces 
(assuming it is related to the the face recognition feature) and I am afraid 
that I hit more bugs afterwards, at least I have seen in previous upgrades 
that issues may also pop up in the digikam database and I am not not yet there 
:-).

Thanks
Rainer

-- 
Rainer Dorsch
http://bokomoko.de/