The crash happens when creating a freehand path using an xp-pen tablet on macOS. We discussed this on IRC and it probably needs backporting some of tusooa's work on make flake more threadsafe. Backtrace: Process: krita [762] Path: /Applications/krita.app/Contents/MacOS/krita Identifier: org.krita Version: 4.2.7-beta1 (???) Code Type: X86-64 (Native) Parent Process: bash [616] Responsible: krita [762] User ID: 501 Date/Time: 2019-10-01 15:35:34.988 +0200 OS Version: Mac OS X 10.13.6 (17G65) Report Version: 12 Anonymous UUID: 3AA81DC8-10C2-4117-7ABB-DC191CAC9A1E Sleep/Wake UUID: B93C8FCE-3CAC-4CA0-BAD1-E1744AC576CB Time Awake Since Boot: 5700 seconds Time Since Wake: 3100 seconds System Integrity Protection: enabled Crashed Thread: 0 Dispatch queue: com.apple.main-thread Exception Type: EXC_CRASH (SIGABRT) Exception Codes: 0x0000000000000000, 0x0000000000000000 Exception Note: EXC_CORPSE_NOTIFY Application Specific Information: abort() called *** error for object 0x7febcce16800: pointer being freed was not allocated Thread 0 Crashed:: Dispatch queue: com.apple.main-thread 0 libsystem_kernel.dylib 0x00007fff7db19b66 __pthread_kill + 10 1 libsystem_pthread.dylib 0x00007fff7dce4080 pthread_kill + 333 2 libsystem_c.dylib 0x00007fff7da751ae abort + 127 3 libsystem_malloc.dylib 0x00007fff7db73822 free + 521 4 libkritaflake.18.dylib 0x000000010b77d416 KoPathShape::outline() const + 1462 5 libkritaflake.18.dylib 0x000000010b7af24b KoShapeManager::shapesAt(QRectF const&, bool, bool) + 443 6 libkritabasicflakes.18.dylib 0x000000011b66fdb1 KoPencilTool::endPointAtPosition(QPointF const&) + 97 7 libkritabasicflakes.18.dylib 0x000000011b6703d9 KoPencilTool::mouseMoveEvent(KoPointerEvent*) + 57 8 kritadefaulttools.so 0x000000011c8e93ad KisDelegatedTool<KisToolShape, __KisToolPencilLocalTool, DeselectShapesActivationPolicy>::mouseMoveEvent(KoPointerEvent*) + 29 9 libkritaflake.18.dylib 0x000000010b7de5bd KoToolProxy::tabletEvent(QTabletEvent*, QPointF const&) + 301 10 libkritaui.18.dylib 0x0000000109c1ffc8 0x109bfd000 + 143304 11 libkritaui.18.dylib 0x0000000109f3b657 KisInputManager::Private::handleCompressedTabletEvent(QEvent*) + 615 12 libkritaui.18.dylib 0x0000000109f376cb KisInputManager::slotCompressedMoveEvent() + 27 13 org.qt-project.QtCore 0x000000010d6b309c QMetaObject::activate(QObject*, int, int, void**) + 3132 14 libkritaglobal.18.dylib 0x000000010bf74c72 KisSignalCompressor::start() + 66 15 libkritaui.18.dylib 0x0000000109f37490 0x109bfd000 + 3384464 16 libkritaui.18.dylib 0x0000000109f35b8b KisInputManager::eventFilterImpl(QEvent*) + 811 17 libkritaui.18.dylib 0x0000000109f356f7 KisInputManager::eventFilter(QObject*, QEvent*) + 103 18 org.qt-project.QtCore 0x000000010d6820f4 QCoreApplicationPrivate::sendThroughObjectEventFilters(QObject*, QEvent*) + 148 19 org.qt-project.QtWidgets 0x000000010c2e8708 QApplicationPrivate::notify_helper(QObject*, QEvent*) + 248 20 org.qt-project.QtWidgets 0x000000010c2e9e5b QApplication::notify(QObject*, QEvent*) + 1419 21 libkritaui.18.dylib 0x0000000109fac61a KisApplication::notify(QObject*, QEvent*) + 26 22 org.qt-project.QtCore 0x000000010d681e44 QCoreApplication::notifyInternal2(QObject*, QEvent*) + 212 23 org.qt-project.QtWidgets 0x000000010c345a75 0x10c2d8000 + 449141 24 org.qt-project.QtWidgets 0x000000010c342601 0x10c2d8000 + 435713 25 org.qt-project.QtWidgets 0x000000010c2e871d QApplicationPrivate::notify_helper(QObject*, QEvent*) + 269 26 org.qt-project.QtWidgets 0x000000010c2e9b22 QApplication::notify(QObject*, QEvent*) + 594 27 libkritaui.18.dylib 0x0000000109fac61a KisApplication::notify(QObject*, QEvent*) + 26 28 org.qt-project.QtCore 0x000000010d681e44 QCoreApplication::notifyInternal2(QObject*, QEvent*) + 212 29 org.qt-project.QtGui 0x000000010ce1cccb QGuiApplicationPrivate::processTabletEvent(QWindowSystemInterfacePrivate::TabletEvent*) + 1403 30 org.qt-project.QtGui 0x000000010ce0080b QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) + 219 31 libqcocoa.dylib 0x00000001105bc5f0 0x110588000 + 214512 32 libqcocoa.dylib 0x00000001105bcd50 0x110588000 + 216400 33 com.apple.CoreFoundation 0x00007fff55b07d31 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17 34 com.apple.CoreFoundation 0x00007fff55bbf60c __CFRunLoopDoSource0 + 108 35 com.apple.CoreFoundation 0x00007fff55aeace0 __CFRunLoopDoSources0 + 208 36 com.apple.CoreFoundation 0x00007fff55aea15d __CFRunLoopRun + 1293 37 com.apple.CoreFoundation 0x00007fff55ae99b7 CFRunLoopRunSpecific + 487 38 com.apple.HIToolbox 0x00007fff54dc9d96 RunCurrentEventLoopInMode + 286 39 com.apple.HIToolbox 0x00007fff54dc9a0f ReceiveNextEventCommon + 366 40 com.apple.HIToolbox 0x00007fff54dc9884 _BlockUntilNextEventMatchingListInModeWithFilter + 64 41 com.apple.AppKit 0x00007fff5307aa73 _DPSNextEvent + 2085 42 com.apple.AppKit 0x00007fff53810e34 -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 3044 43 com.apple.AppKit 0x00007fff5306f885 -[NSApplication run] + 764 44 libqcocoa.dylib 0x00000001105bbccb 0x110588000 + 212171 45 org.qt-project.QtCore 0x000000010d67d50f QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) + 431 46 org.qt-project.QtCore 0x000000010d682452 QCoreApplication::exec() + 130 47 org.krita 0x0000000108c6d9df main + 10319 48 libdyld.dylib 0x00007fff7d9c9015 start + 1
See also https://forum.kde.org/viewtopic.php?f=139&t=162602
Git commit d5279a0196bbaa08bb505a0db121a156a9d6d341 by Dmitry Kazakov. Committed on 08/10/2019 at 15:26. Pushed by dkazakov into branch 'krita/4.2'. Remove extra update when creating a new shape The update is emitted by KoShapeManager itself, so there is no reason to trigger it manually (it also eases thread-safety concerns, because after adding the shape to shape manager it is no longer safe to access it from the worker thread). M +0 -5 libs/ui/flake/kis_shape_controller.cpp https://invent.kde.org/kde/krita/commit/d5279a0196bbaa08bb505a0db121a156a9d6d341
Git commit d4ee038d34b8a9e3b8fa2e53a09a2bb4da57f576 by Dmitry Kazakov. Committed on 08/10/2019 at 15:26. Pushed by dkazakov into branch 'krita/4.2'. Fix crash when using Pencil Tool with a tablet The patch basically makes KoPathShape::outline() cont-safe. Q_FOREACH doesn't support thread-safety, because it relies on copy-on-write. Every non-const access during Q_FOREACH will casue a detach, which is not safe in multithreaded environment. M +6 -4 libs/flake/KoPathShape.cpp https://invent.kde.org/kde/krita/commit/d4ee038d34b8a9e3b8fa2e53a09a2bb4da57f576
Git commit b67fede2997233fc5303022f439ded895c04cedb by Dmitry Kazakov. Committed on 08/10/2019 at 15:33. Pushed by dkazakov into branch 'master'. Remove extra update when creating a new shape The update is emitted by KoShapeManager itself, so there is no reason to trigger it manually (it also eases thread-safety concerns, because after adding the shape to shape manager it is no longer safe to access it from the worker thread). M +0 -5 libs/ui/flake/kis_shape_controller.cpp https://invent.kde.org/kde/krita/commit/b67fede2997233fc5303022f439ded895c04cedb
Git commit fb81d715fc99d09c0e6fe72759152fd0261592b8 by Dmitry Kazakov. Committed on 08/10/2019 at 15:33. Pushed by dkazakov into branch 'master'. Fix crash when using Pencil Tool with a tablet The patch basically makes KoPathShape::outline() cont-safe. Q_FOREACH doesn't support thread-safety, because it relies on copy-on-write. Every non-const access during Q_FOREACH will casue a detach, which is not safe in multithreaded environment. M +6 -4 libs/flake/KoPathShape.cpp https://invent.kde.org/kde/krita/commit/fb81d715fc99d09c0e6fe72759152fd0261592b8
The user reports that the issue is fixed.