This is a longstanding but infrequent Mac crash that has occurred since at least 4.15. Users have not provided any descriptions.
Callstack from Log
[2017.11.19-04.18.41:283][ 0]LogSlate: Took 0.000322 seconds to synchronously load lazily loaded font '../../../Engine/Content/Editor/Slate/Fonts/FontAwesome.ttf' (139K) [2017.11.19-04.18.41:371][ 1]LogRenderer: Reallocating scene render targets to support 1616x808 Format 10 NumSamples 1 (Frame:1). [2017.11.19-04.19.14:097][541]LogMac: Error: appError called: Assertion failed: ParentIndex != INDEX_NONE [File:/Users/build/Build/++UE4+Release-4.18+Compile/Sync/Engine/Source/Runtime/Slate/Private/Framework/Application/MenuStack.cpp] [Line: 484] [2017.11.19-04.19.14:162][541]LogMac: === Critical error: === SIGSEGV: invalid attempt to access memory at address 0x3 [2017.11.19-04.19.14:162][541]LogMac: 0x07a5299b UE4Editor-Core.dylib!FGenericPlatformMisc::RaiseException(unsigned int) [UnknownFile]) 0x093eec09 UE4Editor-ApplicationCore.dylib!FMacErrorOutputDevice::Serialize(wchar_t const*, ELogVerbosity::Type, FName const&) [UnknownFile]) 0x07d00c9d UE4Editor-Core.dylib!FOutputDevice::Logf(wchar_t const*, ...) [UnknownFile]) 0x07c76efb UE4Editor-Core.dylib!FDebug::AssertFailed(char const*, char const*, int, wchar_t const*, ...) [UnknownFile]) 0x0948eb14 UE4Editor-Slate.dylib!FMenuStack::PostPush(TSharedPtr<IMenu, (ESPMode)0>, TSharedRef<FMenuBase, (ESPMode)0>, EShouldThrottle) [UnknownFile]) 0x0948c075 UE4Editor-Slate.dylib!FMenuStack::PushInternal(TSharedPtr<IMenu, (ESPMode)0> const&, TSharedRef<SWidget, (ESPMode)0> const&, FSlateRect, FPopupTransitionEffect const&, bool, EShouldThrottle, bool, bool) [UnknownFile]) 0x0948abd5 UE4Editor-Slate.dylib!FMenuStack::Push(FWidgetPath const&, TSharedRef<SWidget, (ESPMode)0> const&, FVector2D const&, FPopupTransitionEffect const&, bool, FVector2D const&, TOptional<EPopupMethod>, bool, bool) [UnknownFile]) 0x094b8510 UE4Editor-Slate.dylib!FSlateApplication::PushMenu(TSharedRef<SWidget, (ESPMode)0> const&, FWidgetPath const&, TSharedRef<SWidget, (ESPMode)0> const&, FVector2D const&, FPopupTransitionEffect const&, bool, FVector2D const&, TOptional<EPopupMethod>, bool) [UnknownFile]) 0x0973ea24 UE4Editor-Slate.dylib!SMenuAnchor::SetIsOpen(bool, bool, int) [UnknownFile]) 0x0963ce02 UE4Editor-Slate.dylib!SMenuEntryBlock::UpdateSubMenuState(double, float, bool) [UnknownFile]) 0x096c28c4 UE4Editor-Slate.dylib!TBaseSPMethodDelegateInstance<false, SMenuEntryBlock, (ESPMode)0, EActiveTimerReturnType (double, float), bool>::Execute(double, float) const [UnknownFile]) 0x09f21b54 UE4Editor-SlateCore.dylib!SWidget::ExecuteActiveTimers(double, float) [UnknownFile]) 0x09e69768 UE4Editor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09f1d9aa UE4Editor-SlateCore.dylib!SOverlay::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09e69bd4 UE4Editor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09f1e32f UE4Editor-SlateCore.dylib!SPanel::PaintArrangedChildren(FPaintArgs const&, FArrangedChildren const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09f196d6 UE4Editor-SlateCore.dylib!SPanel::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09e69bd4 UE4Editor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09f1e32f UE4Editor-SlateCore.dylib!SPanel::PaintArrangedChildren(FPaintArgs const&, FArrangedChildren const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09f196d6 UE4Editor-SlateCore.dylib!SPanel::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09e69bd4 UE4Editor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09f1e32f UE4Editor-SlateCore.dylib!SPanel::PaintArrangedChildren(FPaintArgs const&, FArrangedChildren const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09f196d6 UE4Editor-SlateCore.dylib!SPanel::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09e69bd4 UE4Editor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09f1d9aa UE4Editor-SlateCore.dylib!SOverlay::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09e69bd4 UE4Editor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09f1e32f UE4Editor-SlateCore.dylib!SPanel::PaintArrangedChildren(FPaintArgs const&, FArrangedChildren const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09f196d6 UE4Editor-SlateCore.dylib!SPanel::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09e69bd4 UE4Editor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09f19e72 UE4Editor-SlateCore.dylib!SCompoundWidget::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09811422 UE4Editor-Slate.dylib!SScrollBox::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09e69bd4 UE4Editor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09f19e72 UE4Editor-SlateCore.dylib!SCompoundWidget::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x097ddc45 UE4Editor-Slate.dylib!SBorder::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09e69bd4 UE4Editor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09f19e72 UE4Editor-SlateCore.dylib!SCompoundWidget::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09e69bd4 UE4Editor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09f1e32f UE4Editor-SlateCore.dylib!SPanel::PaintArrangedChildren(FPaintArgs const&, FArrangedChildren const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09f196d6 UE4Editor-SlateCore.dylib!SPanel::OnPaint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09e69bd4 UE4Editor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x09e692d9 UE4Editor-SlateCore.dylib!FSlateWindowElementList::FDeferredPaint::ExecutePaint(int, FSlateWindowElementList&, FSlateRect const&) const [UnknownFile]) 0x09e6b034 UE4Editor-SlateCore.dylib!FSlateWindowElementList::PaintDeferred(int, FSlateRect const&) [UnknownFile]) 0x09e6a5ec UE4Editor-SlateCore.dylib!SWidget::Paint(FPaintArgs const&, FGeometry const&, FSlateRect const&, FSlateWindowElementList&, int, FWidgetStyle const&, bool) const [UnknownFile]) 0x094a8013 UE4Editor-Slate.dylib!FSlateApplication::DrawWindowAndChildren(TSharedRef<SWindow, (ESPMode)0> const&, FDrawWindowArgs&) [UnknownFile]) 0x094a9821 UE4Editor-Slate.dylib!FSlateApplication::DrawWindowAndChildren(TSharedRef<SWindow, (ESPMode)0> const&, FDrawWindowArgs&) [UnknownFile]) 0x094a6de4 UE4Editor-Slate.dylib!FSlateApplication::PrivateDrawWindows(TSharedPtr<SWindow, (ESPMode)0>) [UnknownFile]) 0x094a6132 UE4Editor-Slate.dylib!FSlateApplication::DrawWindows() [UnknownFile]) 0x094af2ed UE4Editor-Slate.dylib!FSlateApplication::TickApplication(ESlateTickType, float) [UnknownFile]) 0x094ad296 UE4Editor-Slate.dylib!FSlateApplication::Tick(ESlateTickType) [UnknownFile]) 0x079498de UE4Editor!FEngineLoop::Tick() [UnknownFile]) 0x079517a2 UE4Editor!GuardedMain(wchar_t const*) [UnknownFile]) 0x0795ee40 UE4Editor!-[UE4AppDelegate runGameThread:] [UnknownFile]) 0x07bfcd17 UE4Editor-Core.dylib!-[FCocoaGameThread main] [UnknownFile]) 0x495c46d8 Foundation!__NSThread__start__() [UnknownFile]) 0x6ed706c1 libsystem_pthread.dylib!_pthread_body() [UnknownFile]) 0x6ed7056d libsystem_pthread.dylib!_pthread_body() [UnknownFile]) 0x6ed6fc5d libsystem_pthread.dylib!thread_start() [UnknownFile])
repro steps currently unknown
SEGV_MAPERR at 0x3 UE4Editor-Slate.dylib!FMenuStack::PostPush(TSharedPtr<IMenu, (ESPMode)0>, TSharedRef<FMenuBase,() UE4Editor-Slate.dylib!FMenuStack::PushInternal(TSharedPtr<IMenu, (ESPMode)0> const&, TSharedRef<SWidget,() UE4Editor-Slate.dylib!FMenuStack::Push(FWidgetPath const&, TSharedRef<SWidget,() UE4Editor-Slate.dylib!FSlateApplication::PushMenu(TSharedRef<SWidget, (ESPMode)0> const&, FWidgetPath const&, TSharedRef<SWidget,() UE4Editor-Slate.dylib!SMenuAnchor::SetIsOpen() UE4Editor-Slate.dylib!SMenuEntryBlock::UpdateSubMenuState() UE4Editor-Slate.dylib!TBaseSPMethodDelegateInstance<false, SMenuEntryBlock, (ESPMode)0, EActiveTimerReturnType (double, float), bool>::Execute() UE4Editor-SlateCore.dylib!SWidget::ExecuteActiveTimers() UE4Editor-SlateCore.dylib!SWidget::Paint() UE4Editor-SlateCore.dylib!SOverlay::OnPaint() UE4Editor-SlateCore.dylib!SWidget::Paint() UE4Editor-SlateCore.dylib!SPanel::PaintArrangedChildren() UE4Editor-SlateCore.dylib!SPanel::OnPaint() UE4Editor-SlateCore.dylib!SWidget::Paint() UE4Editor-SlateCore.dylib!SPanel::PaintArrangedChildren() UE4Editor-SlateCore.dylib!SPanel::OnPaint() UE4Editor-SlateCore.dylib!SWidget::Paint() UE4Editor-SlateCore.dylib!SPanel::PaintArrangedChildren() UE4Editor-SlateCore.dylib!SPanel::OnPaint() UE4Editor-SlateCore.dylib!SWidget::Paint() UE4Editor-SlateCore.dylib!SOverlay::OnPaint() UE4Editor-SlateCore.dylib!SWidget::Paint() UE4Editor-SlateCore.dylib!SPanel::PaintArrangedChildren() UE4Editor-SlateCore.dylib!SPanel::OnPaint() UE4Editor-SlateCore.dylib!SWidget::Paint() UE4Editor-SlateCore.dylib!SCompoundWidget::OnPaint() UE4Editor-Slate.dylib!SScrollBox::OnPaint() UE4Editor-SlateCore.dylib!SWidget::Paint() UE4Editor-SlateCore.dylib!SCompoundWidget::OnPaint() UE4Editor-Slate.dylib!SBorder::OnPaint() UE4Editor-SlateCore.dylib!SWidget::Paint() UE4Editor-SlateCore.dylib!SCompoundWidget::OnPaint() UE4Editor-SlateCore.dylib!SWidget::Paint() UE4Editor-SlateCore.dylib!SPanel::PaintArrangedChildren() UE4Editor-SlateCore.dylib!SPanel::OnPaint() UE4Editor-SlateCore.dylib!SWidget::Paint() UE4Editor-SlateCore.dylib!FSlateWindowElementList::FDeferredPaint::ExecutePaint() UE4Editor-SlateCore.dylib!FSlateWindowElementList::PaintDeferred() UE4Editor-SlateCore.dylib!SWidget::Paint() UE4Editor-Slate.dylib!FSlateApplication::DrawWindowAndChildren(TSharedRef<SWindow,() UE4Editor-Slate.dylib!FSlateApplication::DrawWindowAndChildren(TSharedRef<SWindow,() UE4Editor-Slate.dylib!FSlateApplication::PrivateDrawWindows(TSharedPtr<SWindow,() UE4Editor-Slate.dylib!FSlateApplication::DrawWindows() UE4Editor-Slate.dylib!FSlateApplication::TickApplication() UE4Editor-Slate.dylib!FSlateApplication::Tick() UE4Editor!FEngineLoop::Tick() UE4Editor!GuardedMain() UE4Editor!<Unknown> UE4Editor-Core.dylib!<Unknown> Foundation!Unknown() libsystem_pthread.dylib!<Unknown> libsystem_pthread.dylib!<Unknown> libsystem_pthread.dylib!<Unknown>
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