UStruct Compiler Error.

[AAriyAA]

why im getting compiler error when i add a value to either structs :

#pragma once
#include "CoreMinimal.h"
#include "UObject/NoExportTypes.h"
#include "Engine/DataTable.h"
#include "MyStructLibrary.generated.h"
USTRUCT(BlueprintType)
struct FEffectStruct : public FTableRowBase
{
GENERATED_BODY()
UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "EffectStruct")
FString NameOfPhysicalSound;
UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "EffectStruct")
USoundBase* HitSound;
UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "EffectStruct")
class UNiagaraSystem* NiagaraSystemIn;
UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "EffectStruct")
FVector ScaleNiagaraSystemIn = FVector(1);
UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "EffectStruct")
class UNiagaraSystem* NiagaraSystemOut;
UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "EffectStruct")
FVector ScaleNiagaraSystemOut = FVector(1);
UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "EffectStruct")
UMaterialInterface* DecalMat;
// ... Other properties and functions specific to FMyStruct1
};
USTRUCT(BlueprintType)
struct FSwordEffectStruct : public FTableRowBase
{
GENERATED_BODY()
UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "EffectStruct")
FString NameOfPhysicalSound;
UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "EffectStruct")
USoundBase* HitSound;
UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "EffectStruct")
class UNiagaraSystem* NiagaraSystemIn;
UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "EffectStruct")
FVector ScaleNiagaraSystemIn = FVector(1);
UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "EffectStruct")
class UNiagaraSystem* NiagaraSystemOut;

//Either add this value or any other value that would cause a compiler error.
UPROPERTY(BlueprintReadWrite, EditAnywhere, Category = "EffectStruct")
int32 Test =0;
};
UCLASS(BlueprintType)
class THESKYABOVETHECLOUDS_API UMyStructLibrary : public UObject
{
GENERATED_BODY()
public:

// ... Other class members and functions
};

[NikitaAksenov]

Hi!

Can you, please, provide text of an error?

[3dRaven]

@AAriyAA

// ... Other properties and functions specific to FMyStruct1

The line

// ... Other properties and functions specific to FMyStruct1

probably is the part where it fails. Structs & functions don’t mix well

UFUNCTION in USTRUCT?

Reflection system does not support functions in struct, Even thru in C++ class and structs are practically have same capabilities as class, UE4 conventions limits structs to only contain data structures… actually giving structs more sense of existence. Ofcorse non-reflected function in structs will normally work in C++, in fact you can find examples of that in UE4, most notably FVector and FRotator Common practice in UE4 in case of blueprint node can’t be contained in type that it is operating …

[AAriyAA]

Thanks for the replay, I don’t have any function in my UStruct body!

[AAriyAA]

sure :

Severity	Code	Description	Project	File	Line	Suppression State
Error	MSB3073	The command F:\Program Files\Epic Games\UE_5.2\Engine\Build\BatchFiles\Build.bat TheSkyAboveTheCloudsEditor Win64 Development -Project=F:\Unreal Projects\TheSkyAboveTheClouds\TheSkyAboveTheClouds.uproject -WaitMutex -FromMsBuild exited with code 6.	TheSkyAboveTheClouds	C:\Program Files\Microsoft Visual Studio\2022\Enterprise\MSBuild\Microsoft\VC\v170\Microsoft.MakeFile.Targets	44
Error (active)	E1835	attribute deprecated does not apply here	TheSkyAboveTheClouds	F:\Program Files\Epic Games\UE_5.2\Engine\Source\Runtime\CoreUObject\Public\Serialization\BulkData.h	277
Error (active)	E1835	attribute deprecated does not apply here	TheSkyAboveTheClouds	F:\Program Files\Epic Games\UE_5.2\Engine\Source\Runtime\CoreUObject\Public\Serialization\BulkData.h	1201
Error (active)	E0415	no suitable constructor exists to convert from UPTRINT to UE::CoreUObject::Private::FPackedObjectRef	TheSkyAboveTheClouds	F:\Program Files\Epic Games\UE_5.2\Engine\Source\Runtime\CoreUObject\Public\UObject\PackedObjectRef.h	32
Error (active)	E0070	incomplete type is not allowed	TheSkyAboveTheClouds	F:\Program Files\Epic Games\UE_5.2\Engine\Source\Runtime\Core\Public\Containers\StringView.h	406
Error (active)	E0070	incomplete type is not allowed	TheSkyAboveTheClouds	F:\Program Files\Epic Games\UE_5.2\Engine\Source\Runtime\Core\Public\Containers\StringView.h	413
Error (active)	E1455	member function declared with ‘override’ does not override a base class member	TheSkyAboveTheClouds	F:\Program Files\Epic Games\UE_5.2\Engine\Source\Runtime\Core\Public\Serialization\ArchiveProxy.h	157
Error (active)	E1455	member function declared with ‘override’ does not override a base class member	TheSkyAboveTheClouds	F:\Program Files\Epic Games\UE_5.2\Engine\Source\Runtime\Core\Public\Serialization\ArchiveProxy.h	167
Error	C2061	syntax error: identifier ‘AAiBaseTopDownCharacter’	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\TheSkyAboveTheCloudsGameMode.h	20
Error	C2061	syntax error: identifier ‘AAiBaseTopDownCharacter’	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\TheSkyAboveTheCloudsGameMode.h	22
Error	C2065	‘AAiBaseTopDownCharacter’: undeclared identifier	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\TheSkyAboveTheCloudsGameMode.h	25
Error	C2059	syntax error: ‘>’	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\TheSkyAboveTheCloudsGameMode.h	25
Error	C2618	illegal member designator in offsetof	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Intermediate\Build\Win64\UnrealEditor\Inc\TheSkyAboveTheClouds\UHT\TheSkyAboveTheCloudsGameMode.gen.cpp	60
Error	C2065	‘ESwordTypeAttack’: undeclared identifier	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\AAIControllerRelated\UBTTask_Attack.h	33
Error	C2923	‘TEnumAsByte’: ‘ESwordTypeAttack’ is not a valid template type argument for parameter ‘TEnum’	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\AAIControllerRelated\UBTTask_Attack.h	33
Error	C2955	‘TEnumAsByte’: use of class template requires template argument list	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\AAIControllerRelated\UBTTask_Attack.h	33
Error	C2512	‘TEnumAsByte’: no appropriate default constructor available	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Intermediate\Build\Win64\UnrealEditor\Inc\TheSkyAboveTheClouds\UHT\UBTTask_Attack.gen.cpp	142
Error	C2660	‘ATheSkyAboveTheCloudsGameMode::RemoveDettectedAI’: function does not take 1 arguments	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\AAIControllerRelated\AIControllerV1.cpp	108
Error	C2660	‘ATheSkyAboveTheCloudsGameMode::AddDettectedAI’: function does not take 1 arguments	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\AAIControllerRelated\AIControllerV1.cpp	250
Error	C2512	‘TEnumAsByte’: no appropriate default constructor available	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\AAIControllerRelated\UBTTask_Attack.cpp	18
Error	C2450	a switch expression of type ‘TEnumAsByte’ is not valid	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\AAIControllerRelated\UBTTask_Attack.cpp	72
Warning	C4005	‘LOCTEXT_NAMESPACE’: macro redefinition	TheSkyAboveTheClouds	F:\Program Files\Epic Games\UE_5.2\Engine\Source\Runtime\UMG\Public\Blueprint\UserWidget.h	1514
Error	C2672	‘begin’: no matching overloaded function found	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\TheSkyAboveTheCloudsGameMode.cpp	46
Error	C2672	‘end’: no matching overloaded function found	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\TheSkyAboveTheCloudsGameMode.cpp	46
Error	C3536	‘$L0’: cannot be used before it is initialized	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\TheSkyAboveTheCloudsGameMode.cpp	47
Error	C3536	‘$L0’: cannot be used before it is initialized	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\TheSkyAboveTheCloudsGameMode.cpp	47
Error	C2100	illegal indirection	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\TheSkyAboveTheCloudsGameMode.cpp	46
Error	C2440	‘initializing’: cannot convert from ‘int’ to ‘AAiBaseTopDownCharacter *’	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\TheSkyAboveTheCloudsGameMode.cpp	46
Error	C2511	‘void ATheSkyAboveTheCloudsGameMode::AddDettectedAI(AAiBaseTopDownCharacter *)’: overloaded member function not found in ‘ATheSkyAboveTheCloudsGameMode’	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\TheSkyAboveTheCloudsGameMode.cpp	58
Error	C2511	‘void ATheSkyAboveTheCloudsGameMode::RemoveDettectedAI(AAiBaseTopDownCharacter *)’: overloaded member function not found in ‘ATheSkyAboveTheCloudsGameMode’	TheSkyAboveTheClouds	F:\Unreal Projects\TheSkyAboveTheClouds\Source\TheSkyAboveTheClouds\TheSkyAboveTheCloudsGameMode.cpp	62

[AAriyAA]

its just nonsense errors.

[3dRaven]

How about the Ouput field of VS? (I’m guessing you are using visual studio)

Do you have all the needed modules in your build file?

• Niagara
• Engine

[AAriyAA]

yes.
PublicDependencyModuleNames.AddRange(new string[] { "Core", "CoreUObject", "Engine", "InputCore", "HeadMountedDisplay", "NavigationSystem", "AIModule", "Niagara", "EnhancedInput", "GameplayTasks" , "DismembermentSystem" , "PhysicsCore" , "UMG" });