This is a slightly common Mac crash that has occurred since 4.17.1. Users have not provided any descriptions of their actions when the crash occurred.
Callstack from Log
[2017.10.05-15.00.31:683][305]LogMaterial: Missing cached shader map for material M_CobbleStone_Smooth, compiling. [2017.10.05-15.00.31:963][305]Cmd: SELECT NONE [2017.10.05-15.00.35:904][306]Cmd: QUIT_EDITOR [2017.10.05-15.00.36:153][306]LogMac: Error: appError called: Assertion failed: Assertion failed: IsValid() [File:Runtime/Core/Public/Templates/SharedPointer.h] [Line: 824] [2017.10.05-15.00.36:436][306]LogMac: === Critical error: === SIGSEGV: invalid attempt to access memory at address 0x3 [2017.10.05-15.00.36:436][306]LogMac: FGenericPlatformMisc::RaiseException(unsigned int) Address = 0x352225b (filename not found) [in UE4Editor-Core.dylib] FOutputDeviceMacError::Serialize(wchar_t const*, ELogVerbosity::Type, FName const&) Address = 0x373994f (filename not found) [in UE4Editor-Core.dylib] FOutputDevice::Logf(wchar_t const*, ...) Address = 0x38201bd (filename not found) [in UE4Editor-Core.dylib] FDebug::AssertFailed(char const*, char const*, int, wchar_t const*, ...) Address = 0x377308e (filename not found) [in UE4Editor-Core.dylib] FSlateApplicationBase::Get() Address = 0xb255acd (filename not found) [in UE4Editor-SlateCore.dylib] SWindow::RequestDestroyWindow() Address = 0xb28b186 (filename not found) [in UE4Editor-SlateCore.dylib] FDragDropOperation::~FDragDropOperation() Address = 0xb289399 (filename not found) [in UE4Editor-SlateCore.dylib] FSlateApplication::~FSlateApplication() Address = 0xa8b7d85 (filename not found) [in UE4Editor-Slate.dylib] FSlateApplication::~FSlateApplication() Address = 0xa8b966e (filename not found) [in UE4Editor-Slate.dylib] FSlateApplication::Shutdown(bool) Address = 0xa8b4a01 (filename not found) [in UE4Editor-Slate.dylib] FEngineLoop::Exit() Address = 0x342462e (filename not found) [in UE4Editor] GuardedMain(wchar_t const*) Address = 0x3424c40 (filename not found) [in UE4Editor] -[UE4AppDelegate runGameThread:] Address = 0x34325d0 (filename not found) [in UE4Editor] -[FCocoaGameThread main] Address = 0x36f5446 (filename not found) [in UE4Editor-Core.dylib] __NSThread__start__() Address = 0xd09ae8ad (filename not found) [in Foundation] _pthread_body() Address = 0xe4d5193b (filename not found) [in libsystem_pthread.dylib] _pthread_body() Address = 0xe4d51887 (filename not found) [in libsystem_pthread.dylib] thread_start() Address = 0xe4d5108d (filename not found) [in libsystem_pthread.dylib]
repro steps currently unknown
SEGV_MAPERR at 0x3 UE4Editor-SlateCore.dylib!FSlateApplicationBase::Get() UE4Editor-SlateCore.dylib!SWindow::RequestDestroyWindow() UE4Editor-SlateCore.dylib!FDragDropOperation::~FDragDropOperation() UE4Editor-Slate.dylib!FSlateApplication::~FSlateApplication() UE4Editor-Slate.dylib!FSlateApplication::~FSlateApplication() UE4Editor-Slate.dylib!FSlateApplication::Shutdown() UE4Editor!FEngineLoop::Exit() 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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