melt segfaults at end of program execution

[andrewpillar]

Describe the bug

mlt segfaults at the end of the program execution, whether the command melt is executed itself, or is given additional parameters.

To Reproduce

Steps to reproduce the behavior:

1. Run melt as a standalone command.

Expected behavior

When run without arguments, for it to print out usage information and exit cleanly. When run with arguments, for it to render the video as specified via the given script file.

Desktop (please complete the following information):

• OS: Arch
• OS Version 6.17.8-arch1-1
• MLT/melt version: 7.34.1

Additional context

I first noticed this when trying to render a video in Kdenlive. From further investigation I found that mlt is segfaulting when run. The command that was being run from Kdenlive to render the video was,

$ melt -loglevel verbose -progress2 ~/Videos/kdenlive-renderqueue/export-1.mlt

Running this exact same command results in a segfault near the end of the program's execution,

[libx264 @ 0x7fe290201a00] i8c dc,h,v,p: 100%  0%  0%  0%
[libx264 @ 0x7fe290201a00] Weighted P-Frames: Y:0.0% UV:0.0%
[libx264 @ 0x7fe290201a00] kb/s:223.17
[aac @ 0x7fe290202cc0] Qavg: 65536.000
[AVIOContext @ 0x7fe29038ba80] Statistics: 842396 bytes written, 4 seeks, 7 writeouts

[1]    37542 segmentation fault (core dumped)  melt -loglevel verbose -progress2 ~/Videos/kdenlive-renderqueue/export-1.mlt

Even running melt with no arguments results in a similar error,

$ melt
...
  -timings                                 Set the logging level to timings
  -version                                 Show the version and copyright
  -video-track | -hide-audio               Add a video-only track
For more help: <https://www.mltframework.org/>
[1]    46685 segmentation fault (core dumped)  melt

From running melt under GDB I was able to get the following backtrace,

[~]$ gdb melt
GNU gdb (GDB) 16.3
Copyright (C) 2024 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
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:
<https://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
    <http://www.gnu.org/software/gdb/documentation/>.

For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from melt...
(gdb) r
Starting program: /usr/bin/melt
Usage: melt [options] [producer [name=value]* ]+
Options:
  -attach filter[:arg] [name=value]*       Attach a filter to the output
  -attach-cut filter[:arg] [name=value]*   Attach a filter to a cut
  -attach-track filter[:arg] [name=value]* Attach a filter to a track
  -attach-clip filter[:arg] [name=value]*  Attach a filter to a producer
  -audio-track | -hide-video               Add an audio-only track
  -blank frames                            Add blank silence to a track
  -chain id[:arg] [name=value]*            Add a producer as a chain
  -consumer id[:arg] [name=value]*         Set the consumer (sink)
  -debug                                   Set the logging level to debug
  -filter filter[:arg] [name=value]*       Add a filter to the current track
  -getc                                    Get keyboard input using getc
  -group [name=value]*                     Apply properties repeatedly
  -help                                    Show this message
  -jack                                    Enable JACK transport synchronization
  -join clips                              Join multiple clips into one cut
  -link id[:arg] [name=value]*             Add a link to a chain
  -loglevel "quiet" | "panic" | "fatal" |  Set the logging level (least to most)
            "error" | "warning" | "info" | "verbose" | "debug" | "timings"
  -mix length                              Add a mix between the last two cuts
  -mixer transition                        Add a transition to the mix
  -null-track | -hide-track                Add a hidden track
  -profile name                            Set the processing settings
  -progress                                Display progress along with position
  -progress2                               Display progress along with position on a new line
  -query                                   List all of the registered services
  -query "consumers" | "consumer"=id       List consumers or show info about one
  -query "filters" | "filter"=id           List filters or show info about one
  -query "links" | "link"=id               List links or show info about one
  -query "producers" | "producer"=id       List producers or show info about one
  -query "transitions" | "transition"=id   List transitions, show info about one
  -query "profiles" | "profile"=id         List profiles, show info about one
  -query "presets" | "preset"=id           List presets, show info about one
  -query "formats"                         List audio/video formats
  -query "audio_codecs"                    List audio codecs
  -query "video_codecs"                    List video codecs
  -quiet                                   Set the logging level to quiet
  -remove                                  Remove the most recent cut
  -repeat times                            Repeat the last cut
  -repository path                         Set the directory of MLT modules
  -serialise [filename]                    Write the commands to a text file
  -setlocale                               Make numeric strings locale-sensitive
  -silent                                  Do not display position/transport
  -split relative-frame                    Split the last cut into two cuts
  -swap                                    Rearrange the last two cuts
  -track                                   Add a track
  -transition id[:arg] [name=value]*       Add a transition
  -verbose                                 Set the logging level to verbose
  -timings                                 Set the logging level to timings
  -version                                 Show the version and copyright
  -video-track | -hide-audio               Add a video-only track
For more help: <https://www.mltframework.org/>
[Thread 0x7fffd79ff6c0 (LWP 36593) exited]

Thread 1 "melt" received signal SIGSEGV, Segmentation fault.
0x00007ffff056a5f8 in QCoreApplication::notifyInternal2 (receiver=0x55555556f970, event=0x7fffffffdb50)
    at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qcoreapplication.cpp:1109
1109	    return qApp->notify(receiver, event);
(gdb) 
(gdb) bt -full 16
#0  0x00007ffff056a5f8 in QCoreApplication::notifyInternal2 (receiver=0x55555556f970, event=0x7fffffffdb50)
    at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qcoreapplication.cpp:1109
        d = <optimized out>
        threadData = 0x55555594bfe0
        selfRequired = <optimized out>
        result = false
        cbdata = {0x55555556f970, 0x7fffffffdb50, 0x7fffffffdaef}
        scopeLevelCounter = {threadData = 0x55555594bfe0}
#1  0x00007ffff05c532b in QCoreApplication::sendEvent (receiver=<optimized out>, event=0x7fffffffdb50)
    at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qcoreapplication.cpp:1549
No locals.
#2  QObjectPrivate::setParent_helper (this=0x555555ab1140, o=0x0) at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qobject.cpp:2255
        e = {<QEvent> = {_vptr.QEvent = 0x7ffff0a25f28 <vtable for QChildEvent+16>, static staticMetaObject = {d = {superdata = {direct = 0x0}, 
                stringdata = 0x7ffff08df568 <QEvent::qt_staticMetaObjectStaticContent<(anonymous namespace)::qt_meta_tag_ZN6QEventE_t>+1512>, 
                data = 0x7ffff08def80 <QEvent::qt_staticMetaObjectStaticContent<(anonymous namespace)::qt_meta_tag_ZN6QEventE_t>>, static_metacall = 0x0, 
                relatedMetaObjects = 0x0, 
                metaTypes = 0x7ffff0a26180 <QEvent::qt_staticMetaObjectRelocatingContent<(anonymous namespace)::qt_meta_tag_ZN6QEventE_t>>, 
                extradata = 0x0}}, t = 71, m_posted = false, m_spont = false, m_accept = true, m_unused = false, m_reserved = 0, m_inputEvent = 0, 
            m_pointerEvent = 0, m_singlePointEvent = 0}, c = 0x5555559599b0}
        index = <optimized out>
        parentD = 0x555555718730
        q = <optimized out>
        __PRETTY_FUNCTION__ = <optimized out>
#3  0x00007ffff05c316c in QObject::~QObject (this=<optimized out>, this=<optimized out>)
    at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qobject.cpp:1128
        d = <optimized out>
        sharedRefcount = <optimized out>
        cd = <optimized out>
        d = <optimized out>
        sharedRefcount = <optimized out>
        cd = <optimized out>
        ownThread = <optimized out>
        privThread = <optimized out>
        signalSlotMutex = <optimized out>
        locker = <optimized out>
        receiverCount = <optimized out>
        signal = <optimized out>
        connectionList = <optimized out>
        c = <optimized out>
        m = <optimized out>
        needToUnlock = <optimized out>
        node = <optimized out>
        sender = <optimized out>
        m = <optimized out>
        needToUnlock = <optimized out>
        senderData = <optimized out>
        slotObj = <optimized out>
        locksAreTheSame = <optimized out>
#4  0x00007fffd7e17385 in QtWaylandClient::QWaylandGlibEventDispatcher::~QWaylandGlibEventDispatcher (this=<optimized out>, this=<optimized out>)
    at /usr/src/debug/qt6-base/build/src/plugins/platforms/wayland/WaylandClient_autogen/EWIEGA46WW/../../../../../../../qtbase/src/plugins/platforms/wayland/qwaylandeventdispatcher_p.h:55
No locals.
#5  QtWaylandClient::QWaylandGlibEventDispatcher::~QWaylandGlibEventDispatcher (this=<optimized out>, this=<optimized out>)
    at /usr/src/debug/qt6-base/build/src/plugins/platforms/wayland/WaylandClient_autogen/EWIEGA46WW/../../../../../../../qtbase/src/plugins/platforms/wayland/qwaylandeventdispatcher_p.h:55
No locals.
#6  0x00007ffff072e13f in operator() (__closure=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/corelib/thread/qthread_unix.cpp:492
        d = 0x5555558f0e10
        locker = {m_mutex = <optimized out>, m_isLocked = false}
        eventDispatcher = 0x5555559599b0
        this = <optimized out>
#7  (anonymous namespace)::terminate_on_exception<QThreadPrivate::cleanup()::<lambda()> >(struct {...} &&) (t=...)
    at /usr/src/debug/qt6-base/qtbase/src/corelib/thread/qthread_unix.cpp:367
No locals.
#8  0x00007ffff07308d8 in QThreadPrivate::cleanup (this=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/corelib/thread/qthread_unix.cpp:475
No locals.
#9  destroy_current_thread_data (data=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/corelib/thread/qthread_unix.cpp:174
        thread_p = <optimized out>
        thread = <optimized out>
#10 (anonymous namespace)::QThreadDataDestroyer::EarlyMainThread::~EarlyMainThread (this=<optimized out>, this=<optimized out>)
--Type <RET> for more, q to quit, c to continue without paging--
    at /usr/src/debug/qt6-base/qtbase/src/corelib/thread/qthread_unix.cpp:232
        data = <optimized out>
        data = <optimized out>
#11 0x00007ffff7c40c71 in __run_exit_handlers (status=1, listp=0x7ffff7e08680 <__exit_funcs>, run_list_atexit=run_list_atexit@entry=true, 
    run_dtors=run_dtors@entry=true) at exit.c:118
        atfct = <optimized out>
        onfct = <optimized out>
        cxafct = <optimized out>
        arg = <optimized out>
        f = <optimized out>
        new_exitfn_called = 804
        cur = 0x555555718b30
        restart = <optimized out>
#12 0x00007ffff7c40d4e in __GI_exit (status=<optimized out>) at exit.c:148
No locals.
#13 0x00007ffff7c2763c in __libc_start_call_main (main=main@entry=0x555555556020 <main>, argc=argc@entry=1, argv=argv@entry=0x7fffffffde88)
    at ../sysdeps/nptl/libc_start_call_main.h:74
        result = <optimized out>
        unwind_buf = {cancel_jmp_buf = {{jmp_buf = {0, -326869677258909579, 140737488346760, 1, 140737354125312, 93824992262872, -326869677349087115, 
                -326887306860636043}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x7fffffffde88}, data = {prev = 0x0, cleanup = 0x0, 
              canceltype = 0}}}
        not_first_call = <optimized out>
#14 0x00007ffff7c276e9 in __libc_start_main_impl (main=0x555555556020 <main>, argc=1, argv=0x7fffffffde88, init=<optimized out>, fini=<optimized out>, 
    rtld_fini=<optimized out>, stack_end=0x7fffffffde78) at ../csu/libc-start.c:360
No locals.
#15 0x0000555555557e45 in _start ()
No symbol table info available.

Below is the package details of mlt installed on my system,

[~]$ pacman -Qi mlt 
Name            : mlt
Version         : 7.34.1-1
Description     : An open source multimedia framework
Architecture    : x86_64
URL             : https://www.mltframework.org
Licenses        : LGPL-2.1-only
Groups          : None
Provides        : None
Depends On      : gcc-libs  glibc  libebur128
Optional Deps   : ffmpeg: ffmpeg plugin [installed]
                  fftw: plus plugin [installed]
                  fontconfig: gdk plugin [installed]
                  frei0r-plugins: for additional effects [installed]
                  gdk-pixbuf2: gdk plugin [installed]
                  glib2: gdk plugin [installed]
                  jack: JACK sound output plugin [installed]
                  ladspa: LADSPA plugins [installed]
                  libepoxy: opengl plugin [installed]
                  libexif: auto rotate plugin [installed]
                  libglvnd: opengl plugin [installed]
                  libsamplerate: libavresample plugin [installed]
                  libvorbis: vorbis plugin [installed]
                  libx11: SDL1 plugin [installed]
                  libxml2: XML plugin [installed]
                  movit: opengl plugin [installed]
                  opencv: openCV plugin [installed]
                  qt5-base: QT5 plugins [installed]
                  qt5-svg: Qt5 plugins [installed]
                  qt6-base: Qt6 plugin [installed]
                  qt6-5compat: Qt6 plugin [installed]
                  qt6-svg: Qt6 plugin [installed]
                  pango: gdk plugin [installed]
                  python: python bindings [installed]
                  rtaudio: rtaudio plugin [installed]
                  rubberband: audio pitch plugin [installed]
                  sdl2: SDL2 plugin [installed]
                  sdl_image: SDL1 plugin [installed]
                  sdl12-compat: SDL1 plugin [installed]
                  sox: SOX (Audio Swiss Army Knife) plugin [installed]
                  vid.stab: video stabilize plugin [installed]
                  zlib: glaxnimate plugin [installed]
Required By     : kdenlive  shotcut
Optional For    : None
Conflicts With  : None
Replaces        : None
Installed Size  : 9.68 MiB
Packager        : Antonio Rojas <arojas@archlinux.org>
Build Date      : Wed 05 Nov 2025 17:15:43 GMT
Install Date    : Tue 25 Nov 2025 09:21:29 GMT
Install Reason  : Explicitly installed
Install Script  : No
Validated By    : Signature

I've looked around the Internet and haven't come across anyone else experiencing a similar error, so I have a feeling the problem might be with my system and the libraries I have installed, though I don't know what. I first noticed this error after doing a system upgrade, so this only furthers my suspicions about the problem being with something on my end.

[amanhigh]

Bug Confirmation: melt 7.34.1 Segfault

Confirmed the segfault issue on Arch Linux with melt 7.34.1. Reverting to 7.32.0 fixes it.

Environment

• OS: Arch Linux (kernel 6.17.8-arch1-1)
• melt 7.34.1: Broken
• melt 7.32.0: Working
• Test file: MP4 with AAC audio

Verified Logs

melt 7.34.1 - Segfault on preview:

$ timeout 10 melt "/mnt/videos/Editing/Pickup/2024/Faridkot/1721756229824.mp4"
[aac @ 0x7fa1a85a8c80] Could not update timestamps for skipped samples.
Current Frame: ... (progress)
timeout: the monitored command dumped core

melt 7.34.1 - Encoding sometimes works, sometimes segfaults:

$ melt "/mnt/videos/Editing/Pickup/2024/Faridkot/1721756229824.mp4" -consumer avformat:/tmp/test.mp4 vcodec=libx264 acodec=none
[aac @ 0x7f117839eac0] Could not update timestamps for skipped samples.
Current Position:        750
zsh: segmentation fault (core dumped)

melt 7.32.0 - Preview works:

$ timeout 10 melt "/mnt/videos/Editing/Pickup/2024/Faridkot/1721756229824.mp4"
[aac @ 0x7fdd9c5b7c00] Could not update timestamps for skipped samples.
Current Frame: ... (progress to frame 303, no segfault)

Workaround

Downgrade to melt 7.32.0:

# Download from https://archive.archlinux.org/packages/m/mlt/mlt-7.32.0-6-x86_64.pkg.tar.zst
sudo pacman -U mlt-7.32.0-6-x86_64.pkg.tar.zst

The bug affects both preview and encoding modes inconsistently. Shotcut fails because it uses melt for rendering. Regression between 7.32.0 and 7.34.1.

[ddennedy]

In the first post the following suggests the file was actually written OK as it is a x264 end-of-job summary from FFmpeg libs:

[libx264 @ 0x7fe290201a00] i8c dc,h,v,p: 100% 0% 0% 0%
[libx264 @ 0x7fe290201a00] Weighted P-Frames: Y:0.0% UV:0.0%
[ libx264 @ 0x7fe290201a00] kb/s:223.17
[aac @ 0x7fe290202cc0] Qavg: 65536.000
[AVIOContext @ 0x7fe29038ba80] Statistics: 842396 bytes written, 4 seeks, 7 writeouts

That and the backtrace suggests something fails during cleanup at exit (even though it is not required; kernel will cleanup). The posted backtrace does not show any MLT function names. Please test adding melt command line option -abort that tells it to exit abruptly, reducing the cleanup. However, it appears that Qt has installed something using atexit().

Shotcut fails because it uses melt for rendering.

Test one of Shotcut's builds (not Arch package).

[frdbr]

I cannot reproduce crash running MLT from master on Arch and Manjaro.

Encoding works.
Preview only the audio works, the video I get a black screen. (But that is another issue.)

[ddennedy]

@frdbr Are you running Wayland? I think you are using nvidia too, right?

[frdbr]

@frdbr Are you running Wayland? I think you are using nvidia too, right?

Yup, both Wayland and Nvidia.

[bwskin]

I have exactly that problem, archlinux, wayland and amd+nvidia gpus. I can check if disabling nvidia makes any difference

[nickjj]

I get the same problem on Arch + Wayland + AMD GPU.

$ fastfetch
                  -`                     nick@nimo
                 .o+`                    ---------
                `ooo/                    OS: Arch Linux x86_64
               `+oooo:                   Host: N155L (Version 1.0)
              `+oooooo:                  Kernel: Linux 6.17.9-arch1-1
              -+oooooo+:                 Uptime: 50 mins
            `/:-:++oooo+:                Packages: 954 (pacman)
           `/++++/+++++++:               Shell: zsh 5.9
          `/++++++++++++++:              Display (BOE0C4E): 1920x1080 in 15", 60 Hz [Built-in]
         `/+++ooooooooooooo/`            WM: niri (Wayland)
        ./ooosssso++osssssso+`           Cursor: default (24px)
       .oossssso-````/ossssss+`          Terminal: ghostty 1.2.3-arch2
      -osssssso.      :ssssssso.         Terminal Font: Inconsolata Nerd Font (10pt)
     :osssssss/        osssso+++.        CPU: AMD Ryzen 7 6800H (16) @ 4.79 GHz
    /ossssssss/        +ssssooo/-        GPU: AMD Radeon 680M [Integrated]
  `/ossssso+/:-        -:/+osssso+-      Memory: 2.42 GiB / 30.59 GiB (8%)
 `+sso+:-`                 `.-/+oso:     Swap: 0 B / 4.00 GiB (0%)
`++:.                           `-/+/    Disk (/): 43.25 GiB / 914.82 GiB (5%) - ext4
.`                                 `/    Local IP (wlan0): 192.168.50.213/24
                                         Battery (SR Real Battery): 54% (2 hours, 58 mins remaining) [Discharging]
                                         Locale: en_US.UTF-8

nick@nimo ~ $ pacman -Q --info mlt
Name            : mlt
Version         : 7.34.1-1
Description     : An open source multimedia framework
Architecture    : x86_64
URL             : https://www.mltframework.org
Licenses        : LGPL-2.1-only
Groups          : None
Provides        : None
Depends On      : gcc-libs  glibc  libebur128
Optional Deps   : ffmpeg: ffmpeg plugin [installed]
                  fftw: plus plugin [installed]
                  fontconfig: gdk plugin [installed]
                  frei0r-plugins: for additional effects [installed]
                  gdk-pixbuf2: gdk plugin [installed]
                  glib2: gdk plugin [installed]
                  jack: JACK sound output plugin [installed]
                  ladspa: LADSPA plugins [installed]
                  libepoxy: opengl plugin [installed]
                  libexif: auto rotate plugin [installed]
                  libglvnd: opengl plugin [installed]
                  libsamplerate: libavresample plugin [installed]
                  libvorbis: vorbis plugin [installed]
                  libx11: SDL1 plugin [installed]
                  libxml2: XML plugin [installed]
                  movit: opengl plugin [installed]
                  opencv: openCV plugin
                  qt5-base: QT5 plugins [installed]
                  qt5-svg: Qt5 plugins [installed]
                  qt6-base: Qt6 plugin [installed]
                  qt6-5compat: Qt6 plugin [installed]
                  qt6-svg: Qt6 plugin [installed]
                  pango: gdk plugin [installed]
                  python: python bindings [installed]
                  rtaudio: rtaudio plugin
                  rubberband: audio pitch plugin [installed]
                  sdl2: SDL2 plugin [installed]
                  sdl_image: SDL1 plugin
                  sdl12-compat: SDL1 plugin
                  sox: SOX (Audio Swiss Army Knife) plugin
                  vid.stab: video stabilize plugin [installed]
                  zlib: glaxnimate plugin [installed]
Required By     : shotcut
Optional For    : None
Conflicts With  : None
Replaces        : None
Installed Size  : 9.68 MiB
Packager        : Antonio Rojas <arojas@archlinux.org>
Build Date      : Wed 05 Nov 2025 12:15:43 PM EST
Install Date    : Mon 01 Dec 2025 08:32:18 AM EST
Install Reason  : Installed as a dependency for another package
Install Script  : No
Validated By    : Signature

nick@nimo ~ $ pacman -Q --info shotcut
Name            : shotcut
Version         : 25.10.31-1
Description     : Cross-platform Qt based Video Editor
Architecture    : x86_64
URL             : https://www.shotcut.org
Licenses        : GPL3
Groups          : None
Provides        : None
Depends On      : qt6-base  qt6-declarative  qt6-imageformats  qt6-multimedia  qt6-translations  mlt  movit  ffmpeg  libx264  libvpx
                  lame  frei0r-plugins  ladspa  qt6-charts  qt6-websockets
Optional Deps   : swh-plugins: Several audio filters
                  opencv: For motion tracking
Required By     : None
Optional For    : None
Conflicts With  : None
Replaces        : None
Installed Size  : 28.34 MiB
Packager        : Leonidas Spyropoulos <artafinde@archlinux.org>
Build Date      : Fri 07 Nov 2025 06:27:40 PM EST
Install Date    : Mon 01 Dec 2025 08:32:18 AM EST
Install Reason  : Explicitly installed
Install Script  : No
Validated By    : Signature

mltframework/shotcut#1759 has more details.

[ddennedy]

I made a change that might have fixed this, but I have no way of knowing. I do not have an Arch system, but I have a PC with an AMD card that is only a couple of years old. I was hoping to repro this from a live USB, but I have not been able to install it in a live scenario thus far. I did not reproduce it with a Garuda VirtualBox I had and updated.

It would be nice if someone can build and test it. Maybe ask the Arch maintainer to make a patch for the package from the commit 5646c2f.

melt still calls the same thing that atexit() was calling. However, with the patch applied (or git master build), you can run melt with the -abort option to disable cleanup at the end. It still writes and closes the output file, but abort makes it exit without bothering to close threads and free memory, which is not necessary because the kernel automatically cleans up those things from exited processes.

[nickjj]

Based on your comments it sounds like this patch would be ok to release as is because you confirmed the Linux kernel will free this up, it wouldn't be specific to a distro like Arch? Are mostly Arch users reporting this because Arch typically provides the latest release of a package? Other distros might be using an older release that's not affected. I only do web development with Python and Ruby so I'm not sure how memory management is done at the OS level. Sorry for the dumb question here but, are you sure this won't cause a memory leak?

Side topic about Arch, I'm fairly new to it, typically the official Arch repos are dedicated to the latest stable release of a package. However, there is the AUR which is self-guided and can contain anything. Packages from the AUR typically get compiled on the end user's machine. Oftentimes projects use this to push their latest main commits so folks can test it out before a stable release lands in the main package repository. You become your own package maintainer with the AUR.

With that said, AUR packages can be created without needing to push them anywhere by following https://wiki.archlinux.org/title/Creating_packages. It really comes down to adding AUR specific files in specific locations and making sure your build scripts can run successfully (all dependencies are installed, etc.).

[ddennedy]

Today I installed Omarchy on a USB hard drive on my PC with an AMD Radeon RX 7600, and I did not reproduce the problem. It is using the latest arch packages including mlt 7.34.1. Of course, it is using wayland but under hyprland if that matters. I also installed Shotcut, and I can export without failure. Probably some other software installed even though omarchy installs a lot initially. Or something else is different about the environment. I have no plan for what else to do for this; someone who has the problem should try doing something.

[nickjj]

What can we do? A few of us reported the issue who are using Arch.

Is there more system information you want from us?

I'm not using Omarchy btw. It's vanilla Arch with the ISO from their official site. I'm using Niri which is a scrolling window manager.

Maybe you can try using the official Arch ISO instead of Omarchy since Omarchy installs a million packages it will be more difficult to figure out what the discrepancy is.

[nickjj]

Looks like Omarchy sets a ton of environment variables that configure certain things related to Wayland at https://github.com/basecamp/omarchy/blob/master/default/hypr/envs.conf.

I don't have any of those set. Maybe you can try unsetting all of those and relogging back in, then seeing if that makes a difference?

[ddennedy]

Those environment variables either set hyprland things or force wayland usage in libs. I am not doing anything else for this. I know you are not using Omarchy, and that is not the point. If you really want me to use exactly your setup then you need to send me your computer. What you or others can do is compile MLT, reproduce it from your build, and then you can try changes beginning with what I mentioned previously. You do not need to make a package, and I am not going to make a package.