Problem Tracking VLC bug [Solved]

The Doctor · Moderator Joined: 27 Jul 2010 Posts: 2678

After my last update, vlc stopped working. I tried rolling back the vlc version as well as the updated packages. It still sigfaults on startup. I also removed a few KDE components, (kate, okular, ark, kdelibs) and their dependencies, however vlc wasn't built with USE=kde and didn't depend on any of the removed packages. I have vlc built like so:

666threesixes666 · Posted: Sat Aug 03, 2013 4:52 am Post subject:

mine works

this is my setup

vanilla-sources 3.9.8

mkultra@mksrv [ ~ ]$ vlc --version
VLC media player 2.0.7 Twoflower (revision 2.0.6-54-g7dd7e4d)

USE="X a52 aac alsa avahi avcodec avformat cdda cddb dbus dts dvbpsi dvd encode ffmpeg flac fluidsynth fontconfig gcrypt gnome jack libsamplerate mmx mp3 mpeg musepack ncurses ogg opengl png postproc pulseaudio qt4 samba sdl shout sse svg swscale taglib truetype udev vorbis x264 xcb xml xv -aalib (-altivec) -atmo (-audioqueue) -bidi -bluray -dc1394 -debug -dirac (-direct2d) -directfb (-directx) (-dshow) -dvb (-dxva2) -egl -fbosd -gme -gnutls -growl -httpd -ieee1394 (-ios-vout) -kate -kde -libass -libcaca -libnotify -libproxy -libtar -libtiger -linsys -lirc -live -lua (-macosx) (-macosx-audio) (-macosx-dialog-provider) (-macosx-eyetv) (-macosx-qtkit) (-macosx-quartztext) (-macosx-vout) -matroska (-media-library) -modplug -mtp (-neon) -omxil -optimisememory -opus -oss -portaudio -projectm -pvr -rtsp -run-as-root -schroedinger -sdl-image -shine -sid -skins -speex -sqlite -switcher -theora -twolame -upnp -vaapi -vcdx -vlm -v4l (-waveout) (-wingdi) -wma-fixed -xosd -zvbi"

these are the use flags you have that i don't

The Doctor · Moderator Joined: 27 Jul 2010 Posts: 2678

There don't appear to be any major differences other than I am using -gnome and -udev. Since my build is crashing on startup before it can even do simple things like --version or --help, I seriously doubt that support for different features and codecs is used in the code and therefore the source of the sigfault.

However, I don't think that use flags are going to change anything. VLC was working for months and then stopped. I can't even run vlc --version anymore. I suspect either a bug somewhere and I would like to be able to make a report that doesn't waste everyones time.

However, I did manage to get some more useful output. Maybe someone sees something?

666threesixes666 · Posted: Sat Aug 03, 2013 5:14 am Post subject:

i have this file, you dont....
[0x22a3358] main libvlc warning: cannot read /usr/lib64/vlc/plugins/plugins.dat (No such file or directory)

The Doctor · Moderator Joined: 27 Jul 2010 Posts: 2678

Yes there does seem to be a problem there. My laptop with a practically identical setup has that directory and file. I thought it was a simple check for plugins and a warning that it didn't find any.
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The Doctor · Moderator Joined: 27 Jul 2010 Posts: 2678

It isn't the problem. I copied the file from my laptop and it still sigfaults.
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666threesixes666 · Posted: Sat Aug 03, 2013 5:43 am Post subject:

try testing compiling out the uses i don't have

franzf · Advocate Joined: 29 Mar 2005 Posts: 4565

1) read your emerge output!

The Doctor · Moderator Joined: 27 Jul 2010 Posts: 2678

Portage didn't give me any messages after updating vlc. Running clx-cache-gen didn't help, unfortunately.

Thanks for pointing me to gdb. I had no idea it existed. Here is what I got

franzf · Advocate Joined: 29 Mar 2005 Posts: 4565

The Doctor · Moderator Joined: 27 Jul 2010 Posts: 2678

OK, that is better. I'll make sure this hasn't already been reported and post the bug tomorrow. I'm too tired to do it right now.

franzf · Advocate Joined: 29 Mar 2005 Posts: 4565

So it segfaults in hand-written ASM...
Which version of glibc do you use? Which USE-Flags? CFLAGS? (emerge --info would be nice) What about your processor? (cat /proc/cupinfo)
Also the last emerged packages would be nice (qlop -l -> qlop comes with portage-utils), from the point you are sure vlc still worked fine (better more then less).

Did you already try running /usr/lib64/vlc/vlc-cache-gen yourself?
Does it fix the issue?
Probably the error is in this one specific plugin, so does USE="-svg" emerge vlc fix the issue? (Of course, if it does NOT crash anymore after running vlc-cache-gen and you want to check if it is only that plugin, remove plugins.dat, again)

The Doctor · Moderator Joined: 27 Jul 2010 Posts: 2678

I used sys-libs/glibc-2.17:2.2 USE="debug (multilib) suid -gd (-hardened) -nscd -profile (-selinux) -systemtap -vanilla"

my emerge --info

CPU (X4)

666threesixes666 · Posted: Sat Aug 03, 2013 8:13 pm Post subject:

strange my svg works, and yours is giving you problems.... here are my useflags for librsvg

Use flags settings: +gtk, +introspection, -tools, -vala

The Doctor · Moderator Joined: 27 Jul 2010 Posts: 2678

From what franzf said, it sounds like someone tried to hand code some assembly. This may produced efficient code, but it doesn't seem to agree with my processors.
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jasn · Guru Joined: 05 May 2005 Posts: 439 Location: Maryland, US

This sounds a lot like this bug. On my system, I too, can cleanly emerge vlc 2.0.7 by removing the SVG USE flag, but I'll get a segmentation fault when starting vlc. If I remove both the libnotify and svg USE flags, vlc 2.0.7 will emerge cleanly, and start, but when I select a video to play, it then segfaults, as I described in the bug report comment section. I can only use vlc 2.0.7 now, by removing the qt4 USE flag, (of course that means no GUI). In this instance vlc 2.0.7 emerges cleanly, and will actually play a video file using the command line version, cvlc, only. Note this is with both libnotify and svg USE flags enabled.

Good Luck..

The Doctor · Moderator Joined: 27 Jul 2010 Posts: 2678

Interesting. In my case removing svg results in a perfectly usable build. It looks like we may have been hit by two sides of the same bug, although in my case vlc-cache-gen didn't sigfault.
_________________
First things first, but not necessarily in that order.

Apologies if I take a while to respond. I'm currently working on the dematerialization circuit for my blue box.

franzf · Advocate Joined: 29 Mar 2005 Posts: 4565

Whom of you did build qtcore/qtgui with USE="glib"? Anyone qtgui with USE="gtkstyle"?

jasn · Guru Joined: 05 May 2005 Posts: 439 Location: Maryland, US

USE glib yes, gtkstyle no.

franzf · Advocate Joined: 29 Mar 2005 Posts: 4565

Aiii, seems to boil down to an issue with glib >(=)2.35...:
https://bugs.gentoo.org/show_bug.cgi?id=405173#c32
As USE="-qt4" emerge vlc fixed at least vlc-cache-gen, probably the malicious part is inside qt4's glib support.
So just for a quick test, could you reemerge qtcore + qtgui with USE="-glib"? It might cry if you run kde or qtwebkit[+gstreamer], but for the sake of this issue it would be great if you could test this.

For the record:
Just installed vlc-2.0.7[svg, libnotify]. I am running the "malicious" glib-2.36.3-r1. vlc does NOT crash.

[edit] probably it is enough to rebuild qtcore+qtgui (+qtdbus?) after the glib update 2.34->2.36? [/edit]

jasn · Guru Joined: 05 May 2005 Posts: 439 Location: Maryland, US

Thank you for trying to sort this out Franz..

Based on your research and suggestions, this is the results of what I've tried;

Code:

media-video/vlc-2.0.7 USE="X a52 aac alsa avcodec avformat bluray cdda cddb dbus dts dvbpsi dvd egl encode ffmpeg flac fluidsynth fontconfig gcrypt kde libass libnotify matroska mmx mp3 mpeg mtp ncurses ogg opengl opus png postproc projectm qt4 rtsp samba schroedinger sdl skins speex sse svg swscale theora truetype twolame udev v4l vorbis x264 xcb xml xv

3) results with same segmentation fault error emerging media-video/vlc-2.0.7, as reported in the bug report, 405173

As you may have expected, media-video/vlc-2.0.7 continued working correctly even after I downgraded back to dev-libs/glib-2.36.3. However, after re-emerging dev-qt/qtcore-4.8.5 and dev-qt/qtgui-4.8.5 with the glib USE flag enabled, media-video/vlc-2.0.7 continues working normally. Weird huh?

Thanks again. You're certainly closing in on the problem. It looks like it's a complicated bug, (or perhaps series of bugs), this time.

Jason

derbrain · Apprentice Joined: 09 Apr 2005 Posts: 178