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vlc doesnt work on arch (segmentation fault)



  • hey ive been trying to run vlc for a while now and it doesnt seem to work. im running arch linux on my computer.

    when i run vlc this is what i get:

    VLC media player 3.0.10 Vetinari (revision 3.0.10-0-g7f145afa84)
    [000055ad908bf5b0] main libvlc: Running vlc with the default interface. Use 'cvlc' to use vlc without interface.
    [000055ad90953ad0] main playlist: playlist is empty
    qt.qpa.xcb: xcb_shm_create_segment() can't be called for size 17089287076, maximumallowed size is 4294967295
    [1] 16742 segmentation fault (core dumped) vlc

    then it exits

    and this is what the backtrace looks like:

    gdb vlc run
    GNU gdb (GDB) 9.2
    Copyright (C) 2020 Free Software Foundation, Inc.
    License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.
    This is free software: you are free to change and redistribute it.
    There is NO WARRANTY, to the extent permitted by law.
    Type "show copying" and "show warranty" for details.
    This GDB was configured as "x86_64-pc-linux-gnu".
    Type "show configuration" for configuration details.
    For bug reporting instructions, please see:
    http://www.gnu.org/software/gdb/bugs/.
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    http://www.gnu.org/software/gdb/documentation/.

    For help, type "help".
    Type "apropos word" to search for commands related to "word"...
    Reading symbols from vlc...
    (No debugging symbols found in vlc)
    /home/ed/run: No such file or directory.
    (gdb) run
    Starting program: /usr/bin/vlc
    [Thread debugging using libthread_db enabled]
    Using host libthread_db library "/usr/lib/libthread_db.so.1".
    VLC media player 3.0.10 Vetinari (revision 3.0.10-0-g7f145afa84)
    [New Thread 0x7ffff4c52700 (LWP 2245)]
    [New Thread 0x7fffefcd7700 (LWP 2246)]
    [New Thread 0x7fffefbd6700 (LWP 2247)]
    [000055555555a5b0] main libvlc: Running vlc with the default interface.
    [New Thread 0x7fffede8f700 (LWP 2248)]
    [New Thread 0x7fffedb06700 (LWP 2249)]
    [New Thread 0x7fffec8d3700 (LWP 2250)]
    [New Thread 0x7fffd3fff700 (LWP 2251)]
    [New Thread 0x7fffd37fe700 (LWP 2252)]
    [New Thread 0x7fffd2ffd700 (LWP 2253)]
    [New Thread 0x7fffd27fc700 (LWP 2254)]
    [New Thread 0x7fffd1fd7700 (LWP 2255)]
    [00005555555eead0] main playlist: playlist is empty
    qt.qpa.xcb: xcb_shm_create_segment() can't be called for size 17089287076, maximumallowed size is 4294967295

    Thread 5 "vlc" received signal SIGSEGV, Segmentation fault.
    [Switching to Thread 0x7fffede8f700 (LWP 2248)]
    0x00007ffff7eed6c5 in __memmove_avx_unaligned_erms () from /usr/lib/libc.so.6
    (gdb) bt
    #0 0x00007ffff7eed6c5 in __memmove_avx_unaligned_erms () from /usr/lib/libc.so.6
    #1 0x00007fffedcb1523 in ?? () from /usr/lib/libQt5XcbQpa.so.5
    #2 0x00007fffedcb1b22 in ?? () from /usr/lib/libQt5XcbQpa.so.5
    #3 0x00007fffedcb1bcd in ?? () from /usr/lib/libQt5XcbQpa.so.5
    #4 0x00007fffedcb246a in ?? () from /usr/lib/libQt5XcbQpa.so.5
    #5 0x00007fffeed2117d in QBackingStore::flush(QRegion const&, QWindow*, QPoint const&) () from /usr/lib/libQt5Gui.so.5
    #6 0x00007fffef2599ac in ?? () from /usr/lib/libQt5Widgets.so.5
    #7 0x00007fffef25b8b3 in ?? () from /usr/lib/libQt5Widgets.so.5
    #8 0x00007fffef25d441 in ?? () from /usr/lib/libQt5Widgets.so.5
    #9 0x00007fffef25dc9e in ?? () from /usr/lib/libQt5Widgets.so.5
    #10 0x00007fffef2a9950 in ?? () from /usr/lib/libQt5Widgets.so.5
    #11 0x00007fffef24c702 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQt5Widgets.so.5
    #12 0x00007fffee77e69a in QCoreApplication::notifyInternal2(QObject*, QEvent*) () from /usr/lib/libQt5Core.so.5
    #13 0x00007fffeeb5a380 in QGuiApplicationPrivate::processExposeEvent(QWindowSystemInterfacePrivate::ExposeEvent*) () from /usr/lib/libQt5Gui.so.5
    #14 0x00007fffeeb2e6ec in QWindowSystemInterface::sendWindowSystemEvents(QFlagsQEventLoop::ProcessEventsFlag) () from /usr/lib/libQt5Gui.so.5
    #15 0x00007fffedcbbc8c in ?? () from /usr/lib/libQt5XcbQpa.so.5
    #16 0x00007ffff508043c in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
    #17 0x00007ffff50cdfa9 in ?? () from /usr/lib/libglib-2.0.so.0
    #18 0x00007ffff507f221 in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
    #19 0x00007fffee7d7211 in QEventDispatcherGlib::processEvents(QFlagsQEventLoop::ProcessEventsFlag) () from /usr/lib/libQt5Core.so.5
    #20 0x00007fffee77d01c in QEventLoop::exec(QFlagsQEventLoop::ProcessEventsFlag) () from /usr/lib/libQt5Core.so.5
    #21 0x00007fffee7854a4 in QCoreApplication::exec() () from /usr/lib/libQt5Core.so.5
    #22 0x00007fffef816f22 in ?? () from /usr/lib/vlc/plugins/gui/libqt_plugin.so
    #23 0x00007fffef817846 in ?? () from /usr/lib/vlc/plugins/gui/libqt_plugin.so
    #24 0x00007ffff7f5e422 in start_thread () from /usr/lib/libpthread.so.0
    #25 0x00007ffff7e87bf3 in clone () from /usr/lib/libc.so.6
    (gdb) Quit
    (gdb)

    i would appreciate any help i could get


  • Lifetime Qt Champion

    @takti said in vlc doesnt work on arch (segmentation fault):

    arch linux

    Did you already ask Arch Linux community? Could be a known issue.



  • @jsulm if you check the backtrace you would see that its quite obviously a qt issue


  • Lifetime Qt Champion

    @takti This does not change anything. As this is Qt build from Arch Linux (for example on my Ubuntu VLC works just fine). This could be an issue already detected by Arch Linux community and they maybe already have a solution. That's why I suggested to check there. It would even make sense to report this to Arch Linux if not yet happened as others can also be affected.
    The fact that it is crashing in a Qt lib is not a prove of an issue in Qt (of course it can be a Qt issue).


  • Lifetime Qt Champion



  • @jsulm this is my post and i havent gotten any help there. nor have i gotten any help on the vlc forums. and it doesnt seem like anyone is looking to help me here as well.

    since this is a qt forum it might be more helpful to offer me your help assuming it IS a qt5 error instead of saying go somewhere else because it MIGHT be an arch issue



  • @takti This is a Qt Developer forum. Not a support site for all things developed using Qt. If you want some help with some specific code, that when compiled and run it crashes, then we can help with that. You will have to get the code, compile the code (preferrably in debug mode), and provide information about the crash. You will have to post this code on the forum. You look like you know how to use gdb so a crash report with debug symbols after you compile it will be very helpful.

    1. Get vlc code and compile on your system (with debug symbols on).
    2. Use gdb or Qt Creator to find the location where the seg fault occurs and provide this backtrace.
    3. Post the relevant code and backtrace here as text.

  • Lifetime Qt Champion

    @takti You need to understand that most people in this forum are volunteers spending their own time to help others for free. This includes me as well. Since I don't have a solution for your problem I suggested to check somewhere else also.