Using the command in the repro steps on Linux will cause the Editor to crash and CrashReporter to pop up with a callstack.
This behaves differently when tried on Windows with -vulkan. The project started to build but the process ended. Not entirely sure if it crashed or not since CrashReporter did not appear.
This was reported and tested on 4.22 (CL-5660361). This was reproduced on 4.21.2 (CL-4753647) and Main 4.23 (CL-5915573)
Results: CrashReporter will come up with the referenced callstack
Expected: The project launches
Unhandled Exception: SIGSEGV: invalid attempt to read memory at address 0x0000000000000140 [2019.04.17-16.31.12:265][ 0]LogCore: Fatal error! 0x00007fac14a640aa libUE4Editor-ApplicationCore.so!SDL_Vulkan_GetRequiredInstanceExtensions_REAL [/home/bschaefer/UnrealEngine/Engine/Source/ThirdParty/SDL2/SDL-gui-backend/src/video/SDL_video.c:4224] 0x00007fabe3f8344e libUE4Editor-VulkanRHI.so!FVulkanLinuxPlatform::GetInstanceExtensions(TArray<char const*, FDefaultAllocator>&) [/home/qa/UnrealEngine-4.21/Engine/Source/Runtime/VulkanRHI/Private/Linux/VulkanLinuxPlatform.cpp:132] 0x00007fabe3f9cd38 libUE4Editor-VulkanRHI.so!FVulkanDynamicRHI::GetInstanceLayersAndExtensions(TArray<char const*, FDefaultAllocator>&, TArray<char const*, FDefaultAllocator>&, bool&) [/home/qa/UnrealEngine-4.21/Engine/Source/Runtime/VulkanRHI/Private/VulkanLayers.cpp:389] 0x00007fabe3fde005 libUE4Editor-VulkanRHI.so!FVulkanDynamicRHI::CreateInstance() [/home/qa/UnrealEngine-4.21/Engine/Source/Runtime/VulkanRHI/Private/VulkanRHI.cpp:343] 0x00007fabe3fdc93a libUE4Editor-VulkanRHI.so!FVulkanDynamicRHI::InitInstance() [/home/qa/UnrealEngine-4.21/Engine/Source/Runtime/VulkanRHI/Private/VulkanRHI.cpp:626] 0x00007fabe3fdc56a libUE4Editor-VulkanRHI.so!FVulkanDynamicRHI::Init() [/home/qa/UnrealEngine-4.21/Engine/Source/Runtime/VulkanRHI/Private/VulkanRHI.cpp:192] 0x00007fac15191c28 libUE4Editor-RHI.so!RHIInit(bool) [/home/qa/UnrealEngine-4.21/Engine/Source/Runtime/RHI/Private/DynamicRHI.cpp:201] 0x000000000022f5e4 UE4Editor!FEngineLoop::PreInit(char16_t const*) [/home/qa/UnrealEngine-4.21/Engine/Source/Runtime/Launch/Private/LaunchEngineLoop.cpp:1903] 0x0000000000240828 UE4Editor!GuardedMain(char16_t const*) [/home/qa/UnrealEngine-4.21/Engine/Source/Runtime/Launch/Private/Launch.cpp:135] 0x00007fac0fde8e4a libUE4Editor-UnixCommonStartup.so!CommonUnixMain(int, char**, int (*)(char16_t const*)) [/home/qa/UnrealEngine-4.21/Engine/Source/Runtime/Unix/UnixCommonStartup/Private/UnixCommonStartup.cpp:245] 0x00007fac0f80eb97 libc.so.6!__libc_start_main(+0xe6) 0x000000000022c02a UE4Editor!_start(+0x29) Malloc Size=65538 LargeMemoryPoolOffset=539730 Fatal error: [File:/home/qa/UnrealEngine-4.21/Engine/Source/Runtime/ApplicationCore/Private/Linux/LinuxPlatformApplicationMisc.cpp] [Line: 499]
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