MultiMC Segmentation fault

[kharnox]

System Information

MultiMC version: 0.6.5-custom
Operating System: Arch Linux

Summary of the issue or suggestion:

When launching a modpack (Project Ozone 3) MultiMC craches
Segmentation fault

Steps to reproduce the issue (Add more if needed):

1. Launch MultiMC
2. Start modpack
3. MultiMC crash

Suspected cause:

I was able to start MultiMC a few hours ago.
I was having issue when starting a modpack where it would crash because of the graphical driver I was using (nouveau).

According to a post I was checking, the issue was the driver and installing the nvidia driver appeared to have solve the issue.
I installed the nvidia driver using the package manager and the following command to configure it # nvidia-xconfig

I rebooted and now MultiMC crashes.
I thought it would be caused because of how it was compiled, so I reinstalled it from the AUR, but same issue.

Logs/Screenshots:

0.307 D News loading succeeded.
0.335 D Download succeeded: "https://files.multimc.org/translations/index_v2.json"
0.335 D Task "NetJob(Translations Index)" succeeded
0.335 D Got translations index!
0.335 D Dir changed: "/home/kharnox/.local/share/multimc/translations"
0.569 D Download succeeded: "https://status.mojang.com/check"
0.569 D Task "NetJob(Status JSON)" succeeded
0.569 D Finished loading status JSON.
0.569 D Status loading succeeded.
0.974 D Download succeeded: "https://crafatar.com/skins/a2d19a5ce4364e4c86bb6a54affb7732.png"
0.974 D Task "NetJob(Startup player skins download)" succeeded
5.557 D Task "LaunchController(0x5631f53cb730)" starting for the first time
5.557 D Task "RefreshTask(0x5631f51c7bc0)" starting for the first time
5.814 D Processing authentication response.
5.814 D Getting new access token.
5.814 D Finished reading refresh response.
5.814 D Task "RefreshTask(0x5631f51c7bc0)" succeeded
5.814 D Writing account list to "accounts.json"
5.814 D Building JSON data structure.
5.814 D Building account array.
5.814 D Writing account list to file.
5.814 D Saved account list to "accounts.json"

[1] 12979 segmentation fault (core dumped) multimc

Those are the last logs from MultiMC

Additional Info:

[peterix]

Well, I'd say rebuild with debug symbols and get me a stack trace from gdb.

[a-ozkan]

Same problem... after recent Archlinux updates:
icu (63.1-2 -> 64.1-1)
libxml2 (2.9.9-1 -> 2.9.9-2)
harfbuzz (2.4.0-1 -> 2.4.0-2)
harfbuzz-icu (2.4.0-1 -> 2.4.0-2)
qt5-base (5.12.2-1 -> 5.12.2-2)

İf downgrade this packages everythings normal for multimc. But other programs segfault...

[sebastianulm]

Not op but same problem (Archlinux)

Here is a backtrace with debugging symbols:

Thread 1 "MultiMC" received signal SIGSEGV, Segmentation fault.
std::_Sp_counted_ptr_inplace<TextPrint, std::allocator<TextPrint>, (__gnu_cxx::_Lock_policy)2>::_M_get_deleter (this=0x555555a0b710,  type_info node=...)
    at /usr/include/c++/8.2.1/bits/shared_ptr_base.h:573
573		else if (__ti == typeid(_Sp_make_shared_tag))
(gdb) bt
#0  std::_Sp_counted_ptr_inplace<TextPrint, std::allocator<TextPrint>, (__gnu_cxx::_Lock_policy)2>::_M_get_deleter (this=0x555555a0b710,  type_info node=...)
    at /usr/include/c++/8.2.1/bits/shared_ptr_base.h:573
#1  0x00007ffff77a66f6 in std::__shared_count<(__gnu_cxx::_Lock_policy)2>::_M_get_deleter (this=<optimized out>,  type_info node=...) at /usr/include/c++/8.2.1/bits/shared_ptr_base.h:750
#2  std::__shared_ptr<TextPrint, (__gnu_cxx::_Lock_policy)2>::__shared_ptr<std::allocator<TextPrint>, LaunchTask*&, QString const, MessageLevel::Enum> (__tag=..., __a=..., 
    this=<optimized out>) at /usr/include/c++/8.2.1/bits/shared_ptr_base.h:1328
#3  std::shared_ptr<TextPrint>::shared_ptr<std::allocator<TextPrint>, LaunchTask*&, QString const, MessageLevel::Enum> (__a=..., __tag=..., this=<optimized out>)
    at /usr/include/c++/8.2.1/bits/shared_ptr.h:360
#4  std::allocate_shared<TextPrint, std::allocator<TextPrint>, LaunchTask*&, QString const, MessageLevel::Enum> (__a=...) at /usr/include/c++/8.2.1/bits/shared_ptr.h:707
#5  std::make_shared<TextPrint, LaunchTask*&, QString const, MessageLevel::Enum> () at /usr/include/c++/8.2.1/bits/shared_ptr.h:723
#6  MinecraftInstance::createLaunchTask (this=0x555555a7c630, session=std::shared_ptr<AuthSession> (use count 3, weak count 0) = {...})
    at /home/yasuo/git/MultiMC5/api/logic/minecraft/MinecraftInstance.cpp:789
#7  0x000055555565b080 in LaunchController::launchInstance (this=0x7fffec003600) at /usr/include/c++/8.2.1/ext/atomicity.h:96
#8  0x000055555565c4cf in LaunchController::login (this=<optimized out>) at /home/yasuo/git/MultiMC5/application/LaunchController.cpp:181
#9  0x000055555565dc17 in LaunchController::executeTask (this=0x7fffec003600) at /home/yasuo/git/MultiMC5/application/LaunchController.cpp:32
#10 0x00007ffff780c2d3 in Task::start (this=0x7fffec003600) at /home/yasuo/git/MultiMC5/api/logic/tasks/Task.cpp:73
#11 0x000055555561f4e3 in MultiMC::launch (this=0x7fffffffdfd0, instance=std::shared_ptr<BaseInstance> (use count 7, weak count 1) = {...}, online=online@entry=true, 
    profiler=profiler@entry=0x0) at /home/yasuo/git/MultiMC5/api/logic/QObjectPtr.h:64
#12 0x0000555555640852 in MainWindow::activateInstance (this=<optimized out>, instance=...) at /usr/include/c++/8.2.1/ext/atomicity.h:96
#13 0x00005555556412ea in MainWindow::instanceActivated (this=0x555555a164e0, index=...) at /usr/include/c++/8.2.1/bits/shared_ptr.h:129
#14 0x0000555555648fad in QtPrivate::FunctorCall<QtPrivate::IndexesList<0>, QtPrivate::List<QModelIndex const&>, void, void (MainWindow::*)(QModelIndex)>::call (arg=<optimized out>, 
    o=<optimized out>, f=<optimized out>) at /usr/include/qt/QtCore/qobjectdefs_impl.h:184
#15 QtPrivate::FunctionPointer<void (MainWindow::*)(QModelIndex)>::call<QtPrivate::List<QModelIndex const&>, void> (arg=<optimized out>, o=<optimized out>, f=<optimized out>)
    at /usr/include/qt/QtCore/qobjectdefs_impl.h:185
#16 QtPrivate::QSlotObject<void (MainWindow::*)(QModelIndex), QtPrivate::List<QModelIndex const&>, void>::impl (which=1, ret=<optimized out>, a=<optimized out>, r=<optimized out>, 
    this_=<optimized out>) at /usr/include/qt/QtCore/qobjectdefs_impl.h:414
#17 QtPrivate::QSlotObject<void (MainWindow::*)(QModelIndex), QtPrivate::List<QModelIndex const&>, void>::impl (which=<optimized out>, this_=<optimized out>, r=<optimized out>, 
    a=<optimized out>, ret=<optimized out>) at /usr/include/qt/QtCore/qobjectdefs_impl.h:407
#18 0x00007ffff699f980 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/libQt5Core.so.5
#19 0x00007ffff7c95906 in QAbstractItemView::activated(QModelIndex const&) () from /usr/lib/libQt5Widgets.so.5
#20 0x000055555570b856 in GroupView::mouseDoubleClickEvent (this=0x555555a6ca10, event=0x7fffffffd720) at /home/yasuo/git/MultiMC5/application/groupview/GroupView.cpp:424
#21 0x00007ffff7a8078f in QWidget::event(QEvent*) () from /usr/lib/libQt5Widgets.so.5
#22 0x00007ffff7b2786f in QFrame::event(QEvent*) () from /usr/lib/libQt5Widgets.so.5
#23 0x00007ffff7ca250c in QAbstractItemView::viewportEvent(QEvent*) () from /usr/lib/libQt5Widgets.so.5
#24 0x00007ffff6974b0b in QCoreApplicationPrivate::sendThroughObjectEventFilters(QObject*, QEvent*) () from /usr/lib/libQt5Core.so.5
#25 0x00007ffff7a3ee14 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQt5Widgets.so.5
#26 0x00007ffff7a46839 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQt5Widgets.so.5
#27 0x00007ffff6974df9 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () from /usr/lib/libQt5Core.so.5
#28 0x00007ffff7a45b18 in QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool, bool) () from /usr/lib/libQt5Widgets.so.5
#29 0x00007ffff7a9af53 in ?? () from /usr/lib/libQt5Widgets.so.5
#30 0x00007ffff7a9e047 in ?? () from /usr/lib/libQt5Widgets.so.5
#31 0x00007ffff7a3ee24 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQt5Widgets.so.5
#32 0x00007ffff7a465f1 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQt5Widgets.so.5
#33 0x00007ffff6974df9 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () from /usr/lib/libQt5Core.so.5
#34 0x00007ffff6efda50 in QGuiApplicationPrivate::processMouseEvent(QWindowSystemInterfacePrivate::MouseEvent*) () from /usr/lib/libQt5Gui.so.5
#35 0x00007ffff6efef16 in QGuiApplicationPrivate::processWindowSystemEvent(QWindowSystemInterfacePrivate::WindowSystemEvent*) () from /usr/lib/libQt5Gui.so.5
#36 0x00007ffff6ed875c in QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Gui.so.5
#37 0x00007ffff2f7b9ac in ?? () from /usr/lib/libQt5XcbQpa.so.5
#38 0x00007ffff55f77bf in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#39 0x00007ffff55f9739 in ?? () from /usr/lib/libglib-2.0.so.0
#40 0x00007ffff55f977e in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#41 0x00007ffff69cac99 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#42 0x00007ffff6973a8c in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
--Type <RET> for more, q to quit, c to continue without paging--
#43 0x00007ffff697bde6 in QCoreApplication::exec() () from /usr/lib/libQt5Core.so.5
#44 0x00005555556098dd in main (argc=<optimized out>, argv=0x7fffffffe248) at /home/yasuo/git/MultiMC5/application/main.cpp:54


(gdb) info args
this = 0x555555a7c630
session = std::shared_ptr<AuthSession> (use count 3, weak count 0) = {get() = 0x555555a8ddb0}


(gdb) print *this
$1 = {<BaseInstance> = {<QObject> = {<No data fields>}, <std::enable_shared_from_this<BaseInstance>> = {_M_weak_this = std::weak_ptr<BaseInstance> (use count 7, weak count 1) = {
        get() = 0x555555a7c630}}, static staticMetaObject = {d = {superdata = 0x7ffff6c1a040 <QObject::staticMetaObject>, stringdata = 0x7ffff78755e0 <qt_meta_stringdata_BaseInstance>, 
        data = 0x7ffff78754e0 <qt_meta_data_BaseInstance>, static_metacall = 0x7ffff76f0ac0 <BaseInstance::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, 
        relatedMetaObjects = 0x0, extradata = 0x0}}, m_rootDir = {static null = {<No data fields>}, d = 0x555555a78ef0}, 
    m_settings = std::shared_ptr<SettingsObject> (use count 1, weak count 0) = {get() = 0x555555a86ac0}, m_isRunning = true, m_launchProcess = std::shared_ptr<LaunchTask> (empty) = {
      get() = 0x0}, m_timeStarted = {d = {d = 0x169fa09dcaf8f, data = {status = 143, msecs = 1554678144175}}}, m_status = BaseInstance::Status::Present, m_crashed = false, 
    m_hasUpdate = false, m_hasBrokenVersion = false}, static staticMetaObject = {d = {superdata = 0x7ffff78ddba0 <BaseInstance::staticMetaObject>, 
      stringdata = 0x7ffff7871b60 <qt_meta_stringdata_MinecraftInstance>, data = 0x7ffff7871b00 <qt_meta_data_MinecraftInstance>, 
      static_metacall = 0x7ffff76ede60 <MinecraftInstance::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}, 
  m_components = std::shared_ptr<ComponentList> (use count 1, weak count 0) = {get() = 0x555555a8b9e0}, m_mods_model = std::shared_ptr<ModsModel> (empty) = {get() = 0x0}, 
  m_loader_mod_list = std::shared_ptr<SimpleModList> (empty) = {get() = 0x0}, m_core_mod_list = std::shared_ptr<SimpleModList> (empty) = {get() = 0x0}, 
  m_resource_pack_list = std::shared_ptr<SimpleModList> (empty) = {get() = 0x0}, m_texture_pack_list = std::shared_ptr<SimpleModList> (empty) = {get() = 0x0}, 
  m_world_list = std::shared_ptr<WorldList> (empty) = {get() = 0x0}, m_game_options = std::shared_ptr<GameOptions> (empty) = {get() = 0x0}}


(gdb) info frame
Stack level 6, frame at 0x7fffffffc820:
 rip = 0x7ffff77a66f6 in MinecraftInstance::createLaunchTask (/home/yasuo/git/MultiMC5/api/logic/minecraft/MinecraftInstance.cpp:789); saved rip = 0x55555565b080
 called by frame at 0x7fffffffc8b0, caller of frame at 0x7fffffffc820
 source language c++.
 Arglist at 0x7fffffffc738, args: this=0x555555a7c630, session=std::shared_ptr<AuthSession> (use count 3, weak count 0) = {...}
 Locals at 0x7fffffffc738, Previous frame's sp is 0x7fffffffc820
 Saved registers:
  rbx at 0x7fffffffc7e8, rbp at 0x7fffffffc7f0, r12 at 0x7fffffffc7f8, r13 at 0x7fffffffc800, r14 at 0x7fffffffc808, r15 at 0x7fffffffc810, rip at 0x7fffffffc818#

I'll leave that gdb open for a while. Let me know if you need additional stuff. Interesting enough I also want to run project ozone 3 on Archlinux.
Exported from the MultiMC provided by Archlinux and imported it into the fresh build. Build off of 414946c In case you're wondering.

[peterix]

Should be better now. Hopefully. This was a very confusing interaction between std::shared_ptr and QObject...

[sebastianulm]

Cleaned, pulled and rebuild. Works for me.

Thanks!

[Chryseus]

Can also confirm it is now fixed.

[StefanTT]

Yep, this fixes the issue, thank you!

For others that find this thread, speaking in Arch Linux terms: the AUR package multimc5 is currently broken as stated above. You need to use multimc-git until a new version of multimc with the fix is released.

[Janrupf]

Interesting, trying to run Project Ozone 3 too on Arch Linux. For some reason it worked before rebooting but now multimc was crashing. Just updated with the git version, but still I'm interested what caused this bug because I don't see a reason.

[StefanTT]

@Janrupf read the answer above in this thread....

[kharnox]

Will try this as soon as I can. Thanks @sebastianulm for providing the gdb trace :)

[Janrupf]

I did @StefanTT, however, I'm still not sure what exactly caused this (as it happened out of nowhere)

[peterix]

This is the closest thing I found: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58822

I'll just call it template madness and move on.

[coreybruce]

Mine builds and launches but as soon as I run minecraft it crashes and shows Segmentation fault (core dumped) in the terminal on Manjaro

[coreybruce]

Confirmed using MutliMC-git for now is a workaround and working version of MultiMC until it gets fixed.

[votex09]

I was also having the same issue, after reading this post and trying to rebuild multimc5 from AUR it appears the patch has been applied to the non-git version.