Compiling the engine from source on Linux and getting a error of "make*** Error 6"

Ok, I got it…

#undef ArraySize

It needs to be added where the ArraySize macro is causing the issue: RHIResources.h
( path = …/Engine/Source/Runtime/RHI/Public/RHIResources.h)

// Copyright Epic Games, Inc. All Rights Reserved.

#pragma once

#include "CoreTypes.h"
#include "Misc/AssertionMacros.h"
#include "HAL/UnrealMemory.h"
#include "Containers/Array.h"
#include "Misc/Crc.h"
#include "Containers/UnrealString.h"
#include "UObject/NameTypes.h"
#include "Math/Color.h"
#include "Containers/StaticArray.h"
#include "HAL/ThreadSafeCounter.h"
#include "RHIDefinitions.h"
#include "Templates/RefCounting.h"
#include "PixelFormat.h"
#include "Containers/LockFreeList.h"
#include "Misc/SecureHash.h"
#include "Hash/CityHash.h"
#include "Async/TaskGraphInterfaces.h"
#include "Serialization/MemoryImage.h"

#define DISABLE_RHI_DEFFERED_DELETE 0

#undef ArraySize //--------------------------------------------new line added

struct FClearValueBinding;
struct FRHIResourceInfo;
struct FGenerateMipsStruct;
enum class EClearBinding;

/** The base type of RHI resources. */
class RHI_API FRHIResource
{
public:
	FRHIResource(bool InbDoNotDeferDelete = false)
		: MarkedForDelete(0)
		, bDoNotDeferDelete(InbDoNotDeferDelete)
		, bCommitted(true)
	{
	}
(...)

I.T. is amazing.

Now I have:

make: *** [Makefile:1048 : UnrealEditor] Erreur 6

Line 1047 & 1048 of Makefile:

UnrealEditor:
	 $(BUILD) UnrealEditor Linux Development  $(ARGS)

Yay, new problem, new game. Trying this solution.

Doesn’t work… so the issue is:

Compile Module.DirectLink.cpp
In file included from .../UnrealEngine-ue5-early-access/Engine/Plugins/Experimental/GeometryProcessing/Intermediate/Build/Linux/B4D820EA/UnrealEditor/Development/GeometryAlgorithms/Module.GeometryAlgorithms.cpp:27:
.../UnrealEngine-ue5-early-access/Engine/Plugins/Experimental/GeometryProcessing/Source/GeometryAlgorithms/Private/ThirdParty/GTEngine/Mathematics/GteTetrahedronKey.cpp:78:27: error: explicit specialization of 'TetrahedronKey' after instantiation
    TetrahedronKey<true>::TetrahedronKey(int v0, int v1, int v2, int v3)
                          ^
.../UnrealEngine-ue5-early-access/Engine/Plugins/Experimental/GeometryProcessing/Source/GeometryAlgorithms/Private/ThirdParty/GTEngine/Mathematics/GteTSManifoldMesh.cpp:73:26: note: implicit instantiation first required here
    TetrahedronKey<true> skey(v0, v1, v2, v3);
                         ^
[871/2990] Compile Module.DMXProtocol.gen.cpp
[872/2990] Compile Module.MaterialBaking.gen.cpp
[873/2990] Compile Module.DatasmithContent.cpp
1 error generated.

Shouldn’t be that hard to fix…