segfault on startup when built with qt5=1

[nik.martin]

just fetched from master, and ran:
scons -c
scons -j4 optimize=native qt5=1

then running ./mixxx with : gdb --args ./mixxx --resourcePath res/ --settingsPath ~/.mixxx

produces this backtrace in gdb:

Thread 27 (Thread 0x7f8d18d62700 (LWP 2662)):
#0 0x00007f8df4b49e9d in poll () at /usr/lib/libc.so.6
#1 0x00007f8df702fd31 in () at /usr/lib/libusb-1.0.so.0
#2 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#3 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 26 (Thread 0x7f8d195ba700 (LWP 2661)):
#0 0x00007f8df744e1ad in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1 0x00007f8df97d25ec in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/libQt5Core.so.5
#2 0x00007f8df97cad0c in QSemaphore::acquire(int) () at /usr/lib/libQt5Core.so.5
#3 0x000000010083c9b6 in VSyncThread::run() (this=0x1083428f0) at src/waveform/vsyncthread.cpp:100
#4 0x00007f8df97d115b in () at /usr/lib/libQt5Core.so.5
#5 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#6 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 25 (Thread 0x7f8d19ffb700 (LWP 2660)):
#0 0x00007f8df4b49e9d in poll () at /usr/lib/libc.so.6
#1 0x00007f8df5707c09 in () at /usr/lib/libglib-2.0.so.0
#2 0x00007f8df5707d1c in g_main_context_iteration () at /usr/lib/libglib-2.0.so.0
#3 0x00007f8df9a0f061 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#4 0x00007f8df99b2ffb in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#5 0x00007f8df97cc40e in QThread::exec() () at /usr/lib/libQt5Core.so.5
#6 0x00007f8df97d115b in () at /usr/lib/libQt5Core.so.5
#7 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#8 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 24 (Thread 0x7f8d1a7fc700 (LWP 2659)):
#0 0x00007f8df744e1ad in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1 0x00007f8df97d25ec in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/libQt5Core.so.5
#2 0x000000010011c980 in AnalyzerQueue::dequeueNextBlocking() (this=this@entry=0x108349b70) at src/analyzer/analyzerqueue.cpp:142
#3 0x0000000100120fb9 in AnalyzerQueue::execThread() (this=this@entry=0x108349b70) at src/analyzer/analyzerqueue.cpp:322
#4 0x0000000100123f99 in AnalyzerQueue::run() (this=0x108349b70) at src/analyzer/analyzerqueue.cpp:289
#5 0x00007f8df97d115b in () at /usr/lib/libQt5Core.so.5
#6 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#7 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 23 (Thread 0x7f8d1affd700 (LWP 2658)):
#0 0x00007f8df744e1ad in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1 0x00007f8df97d25ec in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/libQt5Core.so.5
#2 0x00000001004f14da in BrowseThread::run() (this=0x108352390) at src/library/browse/browsethread.cpp:79
#3 0x00007f8df97d115b in () at /usr/lib/libQt5Core.so.5
#4 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#5 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 22 (Thread 0x7f8d1b7fe700 (LWP 2657)):
#0 0x00007f8df4b49e9d in poll () at /usr/lib/libc.so.6
#1 0x00007f8df5707c09 in () at /usr/lib/libglib-2.0.so.0
#2 0x00007f8df5707d1c in g_main_context_iteration () at /usr/lib/libglib-2.0.so.0
#3 0x00007f8df9a0f061 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#4 0x00007f8df99b2ffb in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#5 0x00007f8df97cc40e in QThread::exec() () at /usr/lib/libQt5Core.so.5
#6 0x00000001005f10bb in LibraryScanner::run() (this=0x108071070) at src/library/scanner/libraryscanner.cpp:116
#7 0x00007f8df97d115b in () at /usr/lib/libQt5Core.so.5
#8 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#9 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 21 (Thread 0x7f8d1bfff700 (LWP 2656)):
#0 0x00007f8df744e1ad in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1 0x00007f8df97d25ec in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/libQt5Core.so.5
#2 0x00007f8df97cad0c in QSemaphore::acquire(int) () at /usr/lib/libQt5Core.so.5
#3 0x0000000100306d38 in CachingReaderWorker::run() (this=0x107909150) at src/engine/cachingreaderworker.cpp:95
#4 0x00007f8df97d115b in () at /usr/lib/libQt5Core.so.5
#5 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#6 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 20 (Thread 0x7f8d3d0f8700 (LWP 2655)):
#0 0x00007f8df744e1ad in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1 0x00007f8df97d25ec in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/libQt5Core.so.5
#2 0x00007f8df97cad0c in QSemaphore::acquire(int) () at /usr/lib/libQt5Core.so.5
#3 0x0000000100306d38 in CachingReaderWorker::run() (this=0x1072f44c0) at src/engine/cachingreaderworker.cpp:95
#4 0x00007f8df97d115b in () at /usr/lib/libQt5Core.so.5
#5 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#6 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 19 (Thread 0x7f8d3ddfa700 (LWP 2654)):
#0 0x00007f8df744e1ad in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1 0x00007f8df97d25ec in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/libQt5Core.so.5
#2 0x00007f8df97cad0c in QSemaphore::acquire(int) () at /usr/lib/libQt5Core.so.5
#3 0x0000000100306d38 in CachingReaderWorker::run() (this=0x106c44c00) at src/engine/cachingreaderworker.cpp:95
#4 0x00007f8df97d115b in () at /usr/lib/libQt5Core.so.5
#5 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#6 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 18 (Thread 0x7f8d3eafc700 (LWP 2653)):
#0 0x00007f8df744e1ad in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1 0x00007f8df97d25ec in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/libQt5Core.so.5
#2 0x00007f8df97cad0c in QSemaphore::acquire(int) () at /usr/lib/libQt5Core.so.5
#3 0x0000000100306d38 in CachingReaderWorker::run() (this=0x1065950b0) at src/engine/cachingreaderworker.cpp:95
#4 0x00007f8df97d115b in () at /usr/lib/libQt5Core.so.5
#5 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#6 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 17 (Thread 0x7f8d3f7fe700 (LWP 2652)):
#0 0x00007f8df744e1ad in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1 0x00007f8df97d25ec in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/libQt5Core.so.5
#2 0x00007f8df97cad0c in QSemaphore::acquire(int) () at /usr/lib/libQt5Core.so.5
#3 0x0000000100306d38 in CachingReaderWorker::run() (this=0x10615e3b0) at src/engine/cachingreaderworker.cpp:95
#4 0x00007f8df97d115b in () at /usr/lib/libQt5Core.so.5
#5 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#6 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 16 (Thread 0x7f8d3ffff700 (LWP 2651)):
#0 0x00007f8df744e1ad in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1 0x00007f8df97d25ec in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/libQt5Core.so.5
#2 0x00007f8df97cad0c in QSemaphore::acquire(int) () at /usr/lib/libQt5Core.so.5
#3 0x0000000100306d38 in CachingReaderWorker::run() (this=0x1057520d0) at src/engine/cachingreaderworker.cpp:95
#4 0x00007f8df97d115b in () at /usr/lib/libQt5Core.so.5
#5 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#6 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 15 (Thread 0x7f8d45302700 (LWP 2650)):
#0 0x00007f8df744e1ad in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1 0x00007f8df97d25ec in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/libQt5Core.so.5
#2 0x00007f8df97cad0c in QSemaphore::acquire(int) () at /usr/lib/libQt5Core.so.5
#3 0x0000000100306d38 in CachingReaderWorker::run() (this=0x104d07730) at src/engine/cachingreaderworker.cpp:95
#4 0x00007f8df97d115b in () at /usr/lib/libQt5Core.so.5
#5 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#6 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 14 (Thread 0x7f8d46004700 (LWP 2649)):
#0 0x00007f8df744e1ad in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1 0x00007f8df97d25ec in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/libQt5Core.so.5
#2 0x000000010080f00e in VinylControlProcessor::run() (this=0x10424bd60) at src/vinylcontrol/vinylcontrolprocessor.cpp:133
#3 0x00007f8df97d115b in () at /usr/lib/libQt5Core.so.5
#4 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#5 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 8 (Thread 0x7f8d470e8700 (LWP 2642)):
#0 0x00007f8df744e1ad in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1 0x00007f8df97d25ec in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/libQt5Core.so.5
#2 0x0000000100472ad5 in EngineSideChain::run() (this=0x101c161a0) at src/engine/sidechain/enginesidechain.cpp:118
#3 0x00007f8df97d115b in () at /usr/lib/libQt5Core.so.5
#4 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#5 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 7 (Thread 0x7f8d478e9700 (LWP 2641)):
#0 0x00007f8df744e1ad in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1 0x00007f8df97d25ec in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/libQt5Core.so.5
#2 0x00000001004472cc in EngineWorkerScheduler::run() (this=0x1012e1310) at src/engine/engineworkerscheduler.cpp:57
#3 0x00007f8df97d115b in () at /usr/lib/libQt5Core.so.5
#4 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#5 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 6 (Thread 0x7f8dc94d3700 (LWP 2640)):
#0 0x00007f8df744e1ad in pthread_cond_wait@@GLIBC_2.3.2 () at /usr/lib/libpthread.so.0
#1 0x00007f8dfbc9eb04 in () at /usr/lib/libQt5Script.so.5
#2 0x00007f8dfbc9eb49 in () at /usr/lib/libQt5Script.so.5
#3 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#4 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 5 (Thread 0x7f8dd8c29700 (LWP 2639)):
#0 0x00007f8df4b49e9d in poll () at /usr/lib/libc.so.6
#1 0x00007f8df5707c09 in () at /usr/lib/libglib-2.0.so.0
#2 0x00007f8df5707d1c in g_main_context_iteration () at /usr/lib/libglib-2.0.so.0
#3 0x00007f8df9a0f061 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#4 0x00007f8df99b2ffb in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/libQt5Core.so.5
#5 0x00007f8df97cc40e in QThread::exec() () at /usr/lib/libQt5Core.so.5
#6 0x00007f8df9e2e396 in () at /usr/lib/libQt5DBus.so.5
#7 0x00007f8df97d115b in () at /usr/lib/libQt5Core.so.5
#8 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#9 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 4 (Thread 0x7f8dd9636700 (LWP 2638)):
#0 0x00007f8df4b49e9d in poll () at /usr/lib/libc.so.6
#1 0x00007f8df5707c09 in () at /usr/lib/libglib-2.0.so.0
#2 0x00007f8df5707fa2 in g_main_loop_run () at /usr/lib/libglib-2.0.so.0
#3 0x00007f8def2ad546 in () at /usr/lib/libgio-2.0.so.0
#4 0x00007f8df572eae5 in () at /usr/lib/libglib-2.0.so.0
#5 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#6 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 3 (Thread 0x7f8dd9e37700 (LWP 2637)):
#0 0x00007f8df4b49e9d in poll () at /usr/lib/libc.so.6
#1 0x00007f8df5707c09 in () at /usr/lib/libglib-2.0.so.0
#2 0x00007f8df5707d1c in g_main_context_iteration () at /usr/lib/libglib-2.0.so.0
#3 0x00007f8df5707d61 in () at /usr/lib/libglib-2.0.so.0
#4 0x00007f8df572eae5 in () at /usr/lib/libglib-2.0.so.0
#5 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#6 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 2 (Thread 0x7f8de3a1e700 (LWP 2636)):
#0 0x00007f8df4b49e9d in poll () at /usr/lib/libc.so.6
#1 0x00007f8df48498e0 in () at /usr/lib/libxcb.so.1
#2 0x00007f8df484b679 in xcb_wait_for_event () at /usr/lib/libxcb.so.1
#3 0x00007f8de65b772a in () at /usr/lib/libQt5XcbQpa.so.5
#4 0x00007f8df97d115b in () at /usr/lib/libQt5Core.so.5
#5 0x00007f8df7448049 in start_thread () at /usr/lib/libpthread.so.0
#6 0x00007f8df4b53f0f in clone () at /usr/lib/libc.so.6

Thread 1 (Thread 0x7f8dfd7638c0 (LWP 2629)):
#0 0x00007f8d024b4974 in () at /usr/lib/libQtGui.so.4
#1 0x00007f8dfd58b37a in call_init.part () at /lib64/ld-linux-x86-64.so.2
#2 0x00007f8dfd58b486 in _dl_init () at /lib64/ld-linux-x86-64.so.2
#3 0x00007f8dfd58f93e in dl_open_worker () at /lib64/ld-linux-x86-64.so.2
#4 0x00007f8df4b8de44 in _dl_catch_error () at /usr/lib/libc.so.6
#5 0x00007f8dfd58f15a in _dl_open () at /lib64/ld-linux-x86-64.so.2
#6 0x00007f8df6565ea6 in () at /usr/lib/libdl.so.2
#7 0x00007f8df4b8de44 in _dl_catch_error () at /usr/lib/libc.so.6
#8 0x00007f8df65665a7 in () at /usr/lib/libdl.so.2
#9 0x00007f8df6565f42 in dlopen () at /usr/lib/libdl.so.2
#10 0x00007f8df677901a in Files::loadLibrary(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >) ()
    at /usr/lib/libvamp-hostsdk.so.3
#11 0x00007f8df6789dd3 in _VampHost::Vamp::HostExt::PluginLoader::Impl::enumeratePlugins(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >) () at /usr/lib/libvamp-hostsdk.so.3
#12 0x00007f8df678a7c9 in _VampHost::Vamp::HostExt::PluginLoader::Impl::listPlugins[abi:cxx11]() () at /usr/lib/libvamp-hostsdk.so.3
#13 0x00007f8df678a841 in _VampHost::Vamp::HostExt::PluginLoader::listPlugins[abi:cxx11]() () at /usr/lib/libvamp-hostsdk.so.3
#14 0x0000000100135a04 in mixxx::VampPluginLoader::listPlugins[abi:cxx11]() (this=this@entry=0x7fffffffd897)
    at src/analyzer/vamp/vamppluginloader.cpp:163
#15 0x0000000100682ca8 in DlgPrefBeats::populate() (this=this@entry=0x1211fa0c0) at src/preferences/dialog/dlgprefbeats.cpp:225
#16 0x00000001006852f3 in DlgPrefBeats::DlgPrefBeats(QWidget*, QSharedPointer<ConfigObject<ConfigValue> >) (this=0x1211fa0c0, parent=<optimized out>, _config=...) at src/preferences/dialog/dlgprefbeats.cpp:25
#17 0x00000001006b4e57 in DlgPreferences::DlgPreferences(MixxxMainWindow*, SkinLoader*, SoundManager*, PlayerManager*, ControllerManager*, VinylControlManager*, EffectsManager*, QSharedPointer<ConfigObject<ConfigValue> >, Library*) (this=0x10850f540, mixxx=0x7fffffffdeb0, pSkinLoader=0x1012ac6b0, soundman=0x1024be4a0, pPlayerManager=0x10424ff00, controllers=0x10834a830, pVCManager=0x1024bd7a0, pEffectsManager=0x101309cb0, pConfig=..., pLibrary=0x108071000) at src/preferences/dialog/dlgpreferences.cpp:116
#18 0x000000010064c216 in MixxxMainWindow::initialize(QApplication*, CmdlineArgs const&) (this=this@entry=0x7fffffffdeb0, pApp=pApp@entry=0x7fffffffde80, args=...) at src/mixxx.cpp:347
#19 0x000000010064d5f5 in MixxxMainWindow::MixxxMainWindow(QApplication*, CmdlineArgs const&) (this=0x7fffffffdeb0, pApp=0x7fffffffde80, args=...)
    at src/mixxx.cpp:158
#20 0x00000001000e4d8c in (anonymous namespace)::runMixxx (args=..., app=0x7fffffffde80) at src/main.cpp:43
#21 0x00000001000e4d8c in main(int, char**) (argc=<optimized out>, argv=<optimized out>) at src/main.cpp:125
(gdb) quit

platform is arch linux I have both qt4 and 5 dev libs on my system and have built mixxx many times with both. I did scons -c and rebuilt with scons -j4 optimize=native and it builds and runs fine. the mixxx log is empty when it crashes

[Sean M. Pappalardo (pegasus-renegadetech)]

What signal did it crash with? (Right before the gdb prompt)

[nik.martin (nik-martin)]

I had to rebuild again with qt5=1 to see it:

Thread 1 "mixxx" received signal SIGSEGV, Segmentation fault.
0x00007f52d221f974 in ?? () from /usr/lib/libQtGui.so.4

[Daniel Schürmann (daschuer)]

It is a crash caused by old vamp plugIns build with Qt4
Probably basically the same issue
https://bugs.launchpad.net/mixxx/+bug/1774639

[Daniel Schürmann (daschuer)]

my /usr/local/lib/mixxx/plugins/vamp/libmixxxminimal.so on Linux does not depend on Qt
Your one does without a doubt, looking at the backtrack.

I think your crash will be gone if you rename your /usr/local/lib/mixxx/plugins/vamp and
/usr/lib/mixxx/plugins/vamp folder, right?

Does anyone know when we have fixed this?
Normally the old libmixxxminimal.so should be overwritten by every normal install. Do we need to worry about it?

[Daniel Schürmann (daschuer)]

Fixed in:
https://github.com/mixxxdj/mixxx/pull/1698

[Swiftb0y (swiftb0y)]

Mixxx now uses GitHub for bug tracking. This bug has been migrated to:
https://github.com/mixxxdj/mixxx/issues/8925