Crash while processing delegate callback UE 5.2.1

Development Programming & Scripting C++
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1

My delegate callback that wasn’t having any issues in prior UE versions, is crashing in UE 5.2.1 (was also crashing in 5.2).

Here’s the context:

  1. There is a “Level Challenge Activator” class that derives from a “Challenge Activator interface” class.
UCLASS()
class SPHERESLAPPER_API ULevelChallengeActivator final : public UChallengeActivator_I
  1. That ChallengeActivator interface class implements an ‘onActivationEvent’ callback for a Multicast delegate, and a virtual ‘processActivationEvent’ function that child class implementations are expected to implement.
UCLASS()
class SPHERESLAPPER_API UChallengeActivator_I : public UObject
{
// ...
protected:
	UFUNCTION()
	void onActivationEvent(UBundle* eventArgs);
	virtual void processActivationEvent(UBundle* eventArgs);
  1. Here’s the code for how that works:
void UChallengeActivator_I::onActivationEvent(UBundle* eventArgs) {
	if (EventUtils::EventParamsMatch(mActivationEventParams, eventArgs)) {
		processActivationEvent(eventArgs);
	}
}

void ULevelChallengeActivator::processActivationEvent(UBundle* eventArgs) {
	// do stuff
}

What started happening in UE 5.2:

  1. The LevelChallengeActivator’s processActivationEvent gets called and processed.

  2. Upon LevelChallengeActivator.processActivationEvent completing, I get an ‘Access Violation Reading Location’ exception in the following engine stack function (line that is excepting is bolded):

FORCEINLINE_DEBUGGABLE void FFrame::StepCompiledIn(void* Result, const FFieldClass* ExpectedPropertyType)
{
	if (Code)
	{
		Step(Object, Result);
	}
	else
	{
		checkSlow(ExpectedPropertyType && ExpectedPropertyType->IsChildOf(FProperty::StaticClass()));
		checkSlow(PropertyChainForCompiledIn && PropertyChainForCompiledIn->IsA(ExpectedPropertyType));
		FProperty* Property = (FProperty*)PropertyChainForCompiledIn;
		PropertyChainForCompiledIn = Property->Next;
		**StepExplicitProperty(Result, Property);**
	}
}

If anyone has any insight into why this is happening and/or why it started happening in UE 5.2, that would be great! Thanks in advance!