Bug 360174 - Segmentation fault when using title clips
Summary: Segmentation fault when using title clips
Status: RESOLVED FIXED
Alias: None
Product: kdenlive
Classification: Applications
Component: User Interface & Miscellaneous (show other bugs)
Version: unspecified
Platform: openSUSE Linux
: NOR crash
Target Milestone: ---
Assignee: Jean-Baptiste Mardelle
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2016-03-06 21:35 UTC by Damien
Modified: 2016-07-21 11:17 UTC (History)
2 users (show)

See Also:
Latest Commit:
Version Fixed In:
Sentry Crash Report:


Attachments
backtrace (37.87 KB, text/plain)
2016-03-06 21:36 UTC, Damien
Details
This is the title file I tried to open. (1.12 KB, application/x-kdenlivetitle)
2016-05-24 17:32 UTC, Hendric Stattmann
Details

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Description Damien 2016-03-06 21:35:46 UTC
When adding composite or various transition effects, while previewing the result, kdenlive randomly crashes with segmentation fault.

In the attached backtrace, 

Reproducible: Sometimes
Comment 1 Damien 2016-03-06 21:36:45 UTC
Created attachment 97723 [details]
backtrace
Comment 2 Damien 2016-03-06 21:41:11 UTC
In the attached backtrace I was adding a cairoaffine blend transition. But it crashes with other transitions too. Version is 15.12.2.

However I then restarted kdenlive and re-applied the transition, and this time it worked. So it cannot be easily repeated, but generally I observe a lot of crashes, so kdenlive is not really usable in this state.
Comment 3 Jean-Baptiste Mardelle 2016-03-07 21:38:49 UTC
Thanks for your report. We have a serious issue related to title clips that causes crashes since the Qt5 port. unfortunately, this crash is extremely hard to fix, it triggers a race condition in Qt that we were unable to fix. As a workaround, you can use images or svg files to replace title clips... sorry
Comment 4 Damien 2016-03-07 22:58:52 UTC
As you pointed out the issue is with title clips not transitions. I realized that after writing this post because the backtrace seems to point to a crash when rendering the font. I changed the bug title.

I will use your workaround until this is fixed.
Comment 5 Jean-Baptiste Mardelle 2016-03-12 08:23:09 UTC
Good news, this was finally fixed in MLT's recent GIT, waiting for feedback but this should fix this crash!
Comment 6 Hendric Stattmann 2016-04-18 13:18:59 UTC
Hello,

I also experience a repeatable crash when opening a (simple) title clip in the title editor. 
My setup is as follows (OpenSUSE Tumbleweed):
libmlt++3-0.9.8-69.6.x86_64
libmlt6-0.9.8-69.6.x86_64
libqt5-qtquickcontrols-5.5.1-1.1.x86_64
libqt5-qtimageformats-5.5.1-1.2.x86_64
libqt5-linguist-5.5.1-1.2.x86_64
libqt5-qttools-5.5.1-1.2.x86_64
libqt5-qtgraphicaleffects-5.5.1-1.1.x86_64
kdenlive-16.04.0-1.2.x86_64

I hope you will be able to fix this nasty one, good luck!
Comment 7 Jean-Baptiste Mardelle 2016-04-20 08:38:33 UTC
This will be fixed in MLT 6.2.0 that should be released tomorrow.
Thanks for your patience
Comment 8 Hendric Stattmann 2016-05-02 11:50:47 UTC
Bonjour Jean-Baptiste,

Many thanks for your comment. I have notified the folks from packman that the new version is available, so I hope to have it released into their repositories soon.

Hendric
Comment 9 Wegwerf 2016-05-13 16:30:45 UTC
If there is no reason to keep this bug report open, could you please so kind as to close it as RESOLVED FIXED? Thank you very much!
Comment 10 Hendric Stattmann 2016-05-24 14:30:59 UTC
Sorry to inform you that I still experience this crash with MLT 6.2.0 installed. :-(
I will try to further analyze the problem - maybe it's a hangover from my old project files.
If I can confirm the bug on a new project, this report will most likely have to remain open.
Comment 11 Hendric Stattmann 2016-05-24 14:39:35 UTC
I have to confirm my earlier comment (nr. 10) - I can reproduce the bug under a newly created user with a fresh project. Details of my installation:

OpenSUSE Tumbleweed x_64
libmlt++3-6.2.0-70.2.x86_64
libmlt6-modules-6.2.0-70.2.x86_64
libmlt6-6.2.0-70.2.x86_64
libmlt6-data-6.2.0-70.2.noarch

kdenlive-debuginfo-16.04.1-1.4.x86_64
kdenlive-16.04.1-1.4.x86_64

Anything we can do about this?
Comment 12 Jean-Baptiste Mardelle 2016-05-24 14:42:49 UTC
Hmm, I really thought I had fixed this one.
Can you please post a backtrace ? See instructions at the bottom of this page to create a backtrace :
https://kdenlive.org/node/872

if cou can reproduce the crash with a simple title clip, please also attach the .kdenlive project file here.
Comment 13 Hendric Stattmann 2016-05-24 17:28:11 UTC
Bonsoir Jean-Baptiste,

I can feel your pain! I know how frustrating it is to have a problem that was believed to be solved to pop up again... Anyway, here is the gdb output:
http://pastebin.com/n6vdv6WK

Have fun!
Hendric
Comment 14 Hendric Stattmann 2016-05-24 17:32:00 UTC
Created attachment 99161 [details]
This is the title file I tried to open.

This is how I can reproduce the bug:
1) Open Kdenlive with an empty project
2) In the Project Bin, click on "Add title clip", title clip editor opens
3) Click on the "open file" icon, "file open" dialog appears
4) Select file to open, click OK
-> Crash.
Comment 15 Wegwerf 2016-05-24 18:30:37 UTC
Hendric, from your description  you seem to talk about a completely different bug, this one in particular: https://bugs.kde.org/show_bug.cgi?id=363404 This one has already been fixed.
Comment 16 Hendric Stattmann 2016-05-24 19:12:15 UTC
Dear wegferf,

You are so right! I mistakenly ran into this bug, instead of 363404. 
Therefore, if no other objection arises, this bug here can be closed.

I am also very happy to see that a fix was committed for 363404 as well, so I can start editing my footage again soon.

With regards,
Hendric
Comment 17 Wegwerf 2016-05-24 19:14:36 UTC
I actually tripped onto 363404 just two days ago or so, so I knew immediately when you wrote that you get the crash not on exiting the titler but instead on loading a previously saved titler.

As for the bug history I would also opt for closing it unless the original reporter can reproduce it even with the fixes in place.
Comment 18 Wegwerf 2016-06-05 12:59:32 UTC
Damien, can you please confirm that this bug has been also fixed for you? I would like to ask you then to be so kind as to close this bug report as RESOLVED FIXED if the fix works for you too. Thank you very much!
Comment 19 Damien 2016-06-10 01:31:11 UTC
I could not reproduce it so it seems to be fixed. Thanks for your hard work. Closing the bug as fixed.
Comment 20 Hendric Stattmann 2016-07-21 11:17:08 UTC
I can confirm that the bug does not occur anymore in the most recent release(s) - 16.04.3.

Thank you & best regards!