This is a common crash affecting users in 4.15 and 4.16. This callstack was previously linked to [Link Removed], but that had a specific repro case that was fixed in 4.14. Users are not providing descriptions regarding how they are hitting this crash.
Source Context
2607 LayerDataPtrs.Reset(); // Pointers to all layers' data 2608 LayerDataPtrs.AddUninitialized(Component->WeightmapLayerAllocations.Num()); 2609 LayerNoWeightBlends.Reset(); // NoWeightBlend flags 2610 LayerNoWeightBlends.AddUninitialized(Component->WeightmapLayerAllocations.Num()); 2611 LayerEditDataAllZero.Reset(); // Whether the data we are editing for this layer is all zero 2612 LayerEditDataAllZero.AddUninitialized(Component->WeightmapLayerAllocations.Num()); 2613 2614 for (int32 LayerIdx = 0; LayerIdx < Component->WeightmapLayerAllocations.Num(); LayerIdx++) 2615 { 2616 FWeightmapLayerAllocationInfo& Allocation = Component->WeightmapLayerAllocations[LayerIdx]; 2617 LayerDataPtrs[LayerIdx] = (uint8*)TexDataInfos[Allocation.WeightmapTextureIndex]->GetMipData(0) + ChannelOffsets[Allocation.WeightmapTextureChannel]; 2618 ***** LayerNoWeightBlends[LayerIdx] = Allocation.LayerInfo->bNoWeightBlend; 2619 LayerEditDataAllZero[LayerIdx] = true; 2620 }
repro steps currently unknown
Access violation - code c0000005 (first/second chance not available) UE4Editor_Landscape!FLandscapeEditDataInterface::SetAlphaData() landscapeeditinterface.cpp:2619 UE4Editor_LandscapeEditor!FAlphamapAccessor<1,0>::SetData() landscapeedmodetools.h:967 UE4Editor_LandscapeEditor!FLandscapeToolStrokePaint::Apply() landscapeedmodepainttools.cpp:253 UE4Editor_LandscapeEditor!FLandscapeToolBase<FLandscapeToolStrokePaint>::BeginTool() landscapeedmodetools.h:1339 UE4Editor_LandscapeEditor!FEdModeLandscape::InputKey() landscapeedmode.cpp:1421 UE4Editor_UnrealEd!FEditorModeTools::InputKey() editormodemanager.cpp:712 UE4Editor_UnrealEd!FEditorViewportClient::InputKey() editorviewportclient.cpp:2268 UE4Editor_UnrealEd!FLevelEditorViewportClient::InputKey() leveleditorviewport.cpp:2506 UE4Editor_Engine!FSceneViewport::OnMouseButtonDown() sceneviewport.cpp:481 UE4Editor_Slate!SViewport::OnMouseButtonDown() sviewport.cpp:187 UE4Editor_Slate!<lambda_7097b900f0e4be30d80fb18f98c51ea0>::operator() slateapplication.cpp:4982 UE4Editor_Slate!FEventRouter::Route<FReply,FEventRouter::FBubblePolicy,FPointerEvent,<lambda_7097b900f0e4be30d80fb18f98c51ea0> >() slateapplication.cpp:238 UE4Editor_Slate!FSlateApplication::RoutePointerDownEvent() slateapplication.cpp:4971 UE4Editor_Slate!FSlateApplication::ProcessMouseButtonDownEvent() slateapplication.cpp:4927 UE4Editor_Slate!FSlateApplication::OnMouseDown() slateapplication.cpp:4859 UE4Editor_Core!FWindowsApplication::ProcessDeferredMessage() windowsapplication.cpp:1706 UE4Editor_Core!FWindowsApplication::DeferMessage() windowsapplication.cpp:2120 UE4Editor_Core!FWindowsApplication::ProcessMessage() windowsapplication.cpp:867 UE4Editor_Core!FWindowsApplication::AppWndProc() windowsapplication.cpp:714 user32!UserCallWinProcCheckWow() user32!DispatchMessageWorker() UE4Editor_Core!FWindowsPlatformMisc::PumpMessages() windowsplatformmisc.cpp:980 UE4Editor!FEngineLoop::Tick() launchengineloop.cpp:2977 UE4Editor!GuardedMain() launch.cpp:166 UE4Editor!GuardedMainWrapper() launchwindows.cpp:134 UE4Editor!WinMain() launchwindows.cpp:210 UE4Editor!__scrt_common_main_seh() exe_common.inl:264 kernel32!BaseThreadInitThunk() ntdll!RtlUserThreadStart()
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