Cannot implement child of CPathVolume

[Louspirit]

Describe the bug

I tried to inherit from CPathVolume to add some custom methods. But whenever I call existing methods of the parent inside my new methods, it causes LNK2019 error when packaging.

Reproduction Steps

Declare CpathFinding module in my Game.Build.cs, in PublicDependencyModuleNames.
Make a child class in the game module.

VerminExtermiantorCPathVolume.h

UCLASS()
class VERMINEXTERMINATOR_API AVerminExtermiantorCPathVolume : public ACPathVolume
{

Make some calls to parent methods:

VerminExtermiantorCPathVolume.cpp

FVector AVerminExtermiantorCPathVolume::FindNearestAvailableNodeLocationAroundLocation(FVector WorldLocation, TEnumAsByte<BlueprintUse::ESuccessBranches>& Branches)
{
	uint32 TempID;
	uint32 OriginTreeID = 0xFFFFFFFF;
	CPathOctree* OriginTree = FindLeafByWorldLocation(WorldLocation, OriginTreeID, false);

	if (!OriginTree) {
		Branches = BlueprintUse::ESuccessBranches::Failure;
		return FVector::Zero();
	}

	if (OriginTree && OriginTree->GetIsFree())
	{
		Branches = BlueprintUse::ESuccessBranches::Success;
		return WorldLocationFromTreeID(OriginTreeID);
	}

	uint32 Depth = FMath::Max((uint32)1, ExtractDepth(OriginTreeID) - 1);
	Depth = FMath::Min(Depth, (uint32)OctreeDepth);
	float SearchRange = GetVoxelSizeByDepth(Depth);

	// We double the search range
	FindClosestFreeLeaf(WorldLocation, TempID, SearchRange * 2);
	Branches = BlueprintUse::ESuccessBranches::Success;
	return WorldLocationFromTreeID(TempID);
}

Try to package the game and get the following error:

UATHelper: Packaging (Windows): VerminExtermiantorCPathVolume.cpp.obj : error LNK2019: symbole externe non r�solu "public: unsigned int __cdecl ACPathVolume::ExtractDepth(unsigned int)const " (?ExtractDepth@ACPathVolume@@QEBAII@Z) r�f�renc� dans la fonction "public: struct UE::Math::TVector<double> __cdecl AVerminExtermiantorCPathVolume::FindNearestAvailableNodeLocationAroundLocation(struct UE::Math::TVector<double>,class TEnumAsByte<enum BlueprintUse::ESuccessBranches> &)" (?FindNearestAvailableNodeLocationAroundLocation@AVerminExtermiantorCPathVolume@@QEAA?AU?$TVector@N@Math@UE@@U234@AEAV?$T
EnumAsByte@W4ESuccessBranches@BlueprintUse@@@@@Z)
UATHelper: Packaging (Windows): VerminExtermiantorCPathVolume.cpp.obj : error LNK2019: symbole externe non r�solu "public: float __cdecl ACPathVolume::GetVoxelSizeByDepth(int)const " (?GetVoxelSizeByDepth@ACPathVolume@@QEBAMH@Z) r�f�renc� dans la fonction "public: struct UE::Math::TVector<double> __cdecl AVerminExtermiantorCPathVolume::FindNearestAvailableNodeLocationAroundLocation(struct UE::Math::TVector<double>,class TEnumAsByte<enum BlueprintUse::ESuccessBranches> &)" (?FindNearestAvailableNodeLocationAroundLocation@AVerminExtermiantorCPathVolume@@QEAA?AU?$TVector@N@Math@UE@@U234@AEAV?$TEn
umAsByte@W4ESuccessBranches@BlueprintUse@@@@@Z)

Workaround

declare methods in child header file:

VerminExtermiantorCPathVolume.h

// Override inline parent methode because of link error.
	uint32 ExtractDepth(uint32 TreeID) const
	{
		return (TreeID & DEPTH_MASK) >> DEPTH_0_BITS;
	}

	// Override inline parent methode because of link error.
	float GetVoxelSizeByDepth(int Depth) const
	{
#if WITH_EDITOR
		checkf(Depth <= OctreeDepth, TEXT("CPATH - Graph Generation:::DEPTH was higher than OctreeDepth"));
#endif

		return LookupTable_VoxelSizeByDepth[Depth];
	}

Possible Solution

• Declare inline body in CPathVolume.h file instead of CPathVolume.cpp

or

• Remove the inline keyboard in CPathVolume.h and CPathVolume.cpp

Targeted version

UE5.1

[NonStaticGH]

I didn't actually think someone would be using these methods. They need to be inline for performance reasons, but if declaring the body in .h file fixes the issue, I will look into it