No value will be returned by reference

Development Programming & Scripting
1

While binding event to delegate broadcast call happening in code, I get the following error:

254561-error.png
254561-error.png1052×519 76.3 KB

I think it has to do with the fact I’m returning an array, (saw fixed bugs talking about a NOTE message - not an error)
FoundSessions struct:

// Session result struct
USTRUCT(BlueprintType)
struct FRedIronSessionResult
{
	GENERATED_USTRUCT_BODY()

	UPROPERTY(EditAnywhere, BlueprintReadWrite)
		FName ServerName;
	UPROPERTY(EditAnywhere, BlueprintReadWrite)
		int32 Ping;
	UPROPERTY(EditAnywhere, BlueprintReadWrite)
		int32 MaxNumberOfPlayers;
	UPROPERTY(EditAnywhere, BlueprintReadWrite)
		int32 CurrentNumberOfPlayers;

	FRedIronSessionResult() {}
};

The delegate declaration

DECLARE_DYNAMIC_MULTICAST_DELEGATE_TwoParams(FFindSessionSuccessDelegateCall, bool, bIsSuccess, TArray<FRedIronSessionResult>, FoundSessions);

The binding inside my class (under public:)

	UPROPERTY(BlueprintAssignable, Category = "Sessions|Delegates")
		FFindSessionSuccessDelegateCall OnFindSessionDone;

The broadcast: (from inside one of the .cpp function)

TArray<FRedIronSessionResult> SessionResults;
OnFindSessionDone.Broadcast(false, SessionResults);

What have i done wrong?
Thanks

—edit—
Done some more checking - this is happening with every TArray I try to broadcast, not just my struct.
Is that a bug or am I using it wrong?

2

Are you dragging off the “Event” pin from your “OnFindSessionDone” event and typing “Custom event” to create your custom event with matching signature?

3

Yes I am dragging from the “Event” pin

4

I’ve solved this by using a wrapper to wrap the array, it looks like a bug.

Marking it as solved, yet, no real reason has been given.

5

I’ve been getting this in 4.21.2, it was resolved quite some time ago but has reared its head again.

6

Declare the delegate like this:

DECLARE_DYNAMIC_MULTICAST_DELEGATE_TwoParams(FFindSessionSuccessDelegateCall, bool, bIsSuccess, const TArray<FRedIronSessionResult>&, FoundSessions);
7

This is the right answer