Crash any time a Message is added to Log with Collapse Mode on

[OdinVex]

Background

I noticed there wasn't a Linux compile of UE4_MagicConsole but most plugins can compile without issue or much alteration if merely included in Engine/Plugins/Marketplace. Compile went well, aside from needing to fix an issue regarding regex byte-encoding and adding Linux to the whitelist so that Unreal Engine would compile it. (I created a #7 for those changes.)

Note: Unreal Engine 4.26.2.
Note: Linux x64

Behavior

Any time a message is added to the Enhanced Output Log (when it is open) it will crash if and only if Collapse Mode is on.

Expected Behavior

No crashes.

Steps to Reproduce

1. Open a project.
2. Open Enhanced Output Log.
3. Do anything to add a message to the log with Collapse Mode on.

Failure Logs

`libUE4Editor-Slate.so!FTextBlockStyle::FTextBlockStyle(FTextBlockStyle const&) [/opt/UnrealEngine/Engine/Source/Runtime/SlateCore/Public/Styling/SlateTypes.h:226]

libUE4Editor-Slate.so!FSlateTextRun::FSlateTextRun(FRunInfo const&, TSharedRef<FString const, (ESPMode)0> const&, FTextBlockStyle const&, FTextRange const&) [/opt/UnrealEngine/Engine/Source/Runtime/Slate/Private/Framework/Text/SlateTextRun.cpp:268]

libUE4Editor-Slate.so!FSlateTextRun::Create(FRunInfo const&, TSharedRef<FString const, (ESPMode)0> const&, FTextBlockStyle const&, FTextRange const&) [/opt/UnrealEngine/Engine/Source/Runtime/Slate/Private/Framework/Text/SlateTextRun.cpp:19]

libUE4Editor-ConsoleEnhanced.so!FOutputLogTextLayoutMarshaller::AppendMessagesToTextLayout(TArray<TSharedPtr<FLogMessage, (ESPMode)0>, TSizedDefaultAllocator<32> > const&) [/opt/UnrealEngine/Engine/Plugins/Marketplace/ConsoleEnhanced/Source/ConsoleEnhanced/Private/SOutputLog.cpp:753]

libUE4Editor-ConsoleEnhanced.so!FOutputLogTextLayoutMarshaller::AppendMessage(char16_t const*, ELogVerbosity::Type, double, FName const&) [/opt/UnrealEngine/Engine/Plugins/Marketplace/ConsoleEnhanced/Source/ConsoleEnhanced/Private/SOutputLog.cpp:638]

libUE4Editor-ConsoleEnhanced.so!non-virtual thunk to SOutputLog::Serialize(char16_t const*, ELogVerbosity::Type, FName const&, double) [/opt/UnrealEngine/Engine/Plugins/Marketplace/ConsoleEnhanced/Source/ConsoleEnhanced/Private/SOutputLog.cpp:1301]`

[Cultrarius]

Sorry, I've tried a few times to repro it, but everything works fine for me. I don't have a Linux machine to test it, so that might be the source of the problem.

[OdinVex]

Should leave it open until another Linux user can test. I managed to work around it by disabling it in code.

[Cultrarius]

The issue was open since April, so I don't expect a lot to happen there. But I'll reopen it for you, if it makes you happy ;)

[OdinVex]

The issue was open since April, so I don't expect a lot to happen there. But I'll reopen it for you, if it makes you happy ;)

It's merely about keeping Issues open for visibility. I doubt many people develop enough on Linux to warrant even the plugin, but I enjoyed it and felt I'd do my part.

[OdinVex]

Ported to 5.1.0 (see issue #11). Decided to try enabling Collapsed Mode again:

Assertion failed: IsInGameThread() || IsInSlateThread() || IsInAsyncLoadingThread() [File:Runtime/Slate/Public/Framework/Application/SlateApplication.h] [Line: 255]

libUnrealEditor-Slate.so!FTextLayout::FLineModel::FLineModel(TSharedRef<FString, (ESPMode)1> const&) [./UnrealEngine/Engine/Source/./Runtime/Slate/Private/Framework/Text/TextLayout.cpp:2674]
libUnrealEditor-Slate.so!FTextLayout::AddLines(TArray<FTextLayout::FNewLineData, TSizedDefaultAllocator<32> > const&) [./UnrealEngine/Engine/Source/./Runtime/Slate/Private/Framework/Text/TextLayout.cpp:2164]
libUnrealEditor-ConsoleEnhanced.so!FOutputLogTextLayoutMarshaller::AppendMessagesToTextLayout(TArray<TSharedPtr<FLogMessage, (ESPMode)1>, TSizedDefaultAllocator<32> > const&) [./UnrealEngine/Engine/Source/./../Plugins/Marketplace/ConsoleEnhanced/Source/ConsoleEnhanced/Private/SOutputLog.cpp:793]
libUnrealEditor-ConsoleEnhanced.so!FOutputLogTextLayoutMarshaller::AppendMessage(char16_t const*, ELogVerbosity::Type, double, FName const&) [./UnrealEngine/Engine/Source/./../Plugins/Marketplace/ConsoleEnhanced/Source/ConsoleEnhanced/Private/SOutputLog.cpp:637]
libUnrealEditor-ConsoleEnhanced.so!non-virtual thunk to SOutputLog::Serialize(char16_t const*, ELogVerbosity::Type, FName const&, double) [./UnrealEngine/Engine/Source/./../Plugins/Marketplace/ConsoleEnhanced/Source/ConsoleEnhanced/Private/SOutputLog.cpp:0]
libUnrealEditor-Core.so!void UE::TDepletableMpscQueue<UE::Private::FOutputDeviceLine, UE::Private::FOutputDeviceLinearAllocator>::Consume<UE::Private::FOutputDeviceRedirectorState::FlushBufferedLines()::$_7>(UE::TDepletableMpscQueue<UE::Private::FOutputDeviceLine, UE::Private::FOutputDeviceLinearAllocator>::FNode*, UE::TDepletableMpscQueue<UE::Private::FOutputDeviceLine, UE::Private::FOutputDeviceLinearAllocator>::FNode*, UE::Private::FOutputDeviceRedirectorState::FlushBufferedLines()::$_7 const&)::'lambda0'(UE::TDepletableMpscQueue<UE::Private::FOutputDeviceLine, UE::Private::FOutputDeviceLinearAllocator>::FNode*)::operator()(UE::TDepletableMpscQueue<UE::Private::FOutputDeviceLine, UE::Private::FOutputDeviceLinearAllocator>::FNode*) const [./UnrealEngine/Engine/Source/Runtime/Core/Public/Containers/DepletableMpscQueue.h:130]
libUnrealEditor-Core.so!UE::Private::FOutputDeviceRedirectorState::FlushBufferedLines() [./UnrealEngine/Engine/Source/./Runtime/Core/Private/Misc/OutputDeviceRedirector.cpp:453]
libUnrealEditor-Core.so!UE::Private::FOutputDeviceRedirectorState::ThreadLoop() [./UnrealEngine/Engine/Source/./Runtime/Core/Private/Misc/OutputDeviceRedirector.cpp:436]
libUnrealEditor-Core.so!FThreadImpl::Run() [./UnrealEngine/Engine/Source/./Runtime/Core/Private/HAL/Thread.cpp:67]
libUnrealEditor-Core.so!FRunnableThreadPThread::Run() [./UnrealEngine/Engine/Source/./Runtime/Core/Private/HAL/PThreadRunnableThread.cpp:25]
libUnrealEditor-Core.so!FRunnableThreadPThread::_ThreadProc(void*) [./UnrealEngine/Engine/Source/Runtime/Core/Private/HAL/PThreadRunnableThread.h:185]

Just spit-balling here, but I wonder if the bit of code relating to the old error FTextBlockStyle stuff with this new context might mean something regarding the AppendMessagesToTextLayout block in SOutputLog.cpp. Is something perhaps happening outside the thread and Linux is strict about that whereas Windows can behave wonky? This 'Run' business, maybe Collapsed Mode does something special during that, I mean.

Edit: Apparently happens whether Collapsed is on or off, was lucky it worked before. Possibly a memory access issue. AppendMessagesToTextLayout is always responsible, though. That much is definite.