Pure virtual function call crash

Development Programming & Scripting
1

This actually occurs in 4.12 also the exact same way. Almost always when I’m trying to figure out my inputs and outputs in blueprint. In this case I was just doing the following and it wasn’t even compiled. I just wanted to get the current speed and name of the actor:

111359-gserfgwerfgwef.png
111359-gserfgwerfgwef.png703×553 66.7 KB

I’ll admit it almost always happens when I haven’t done something before. What I don’t get is that if the blueprint didn’t compile, why is anything crashing?

2

Maybe add a cast to your get ControlledPawn or GetOwner call

In c++ it occurs when you call a method that is declare but not defined. The method exist for your given class but it does nothing, your method should provide a String as output but you won t receive it and it causes your script to crash.

It compiles but would not run

3

Hello ,

I have few questions for you that will help narrow down what issue it is that you are experiencing.

Quick questions:

  1. Can you reproduce this issue in a clean project?
  2. If so, could you provide a detailed list of steps to reproduce this issue on our end?
  3. Could you provide and code and/or screen shots of any blueprints/settings that may be involved with this issue?
  4. Could you provide your dxdiag?
4

Hi Rudy, sorry for the wait.

A) Yes, I have it occuring in one of my regular projects and occurring in a Udemy Unreal project video tutorial series.

B) Detailed list of steps, but does not matter in which order, its always pulling a connection from a node and dragging it somewhere.

  1. This always begins in Blueprint. In this instance it was a behavior tree task blueprint.
  2. I had the following set up in this blueprint which caused no issues:

115789-before.png
115789-before.png1920×1080 327 KB

  1. I had deleted the SetFocalPoint node and placed a SetFocus node, then removing “Get Blackboard Value As Vector” and changed it to “Get Blackboard Value As Actor”.
  2. I started hooking everything up and once I got to this point in the following picture, I got the error in the headline. I had a node held with a mouse click and I missed the socket, I think I double clicked or something and then the crash occured. But this always, always happens while I’m currently dragging a node from one place to another.

115790-crash.png
115790-crash.png1920×1080 341 KB

C) The only code I’m using is a Patrol script to set waypoint actors for the AI to walk to and from. The following is PatrolRoute.cpp:

// Fill out your copyright notice in the Description page of Project Settings.

#include "S05_TestingGrounds.h"
#include "PatrolRoute.h"


TArray<AActor*> UPatrolRoute::GetPatrolPoints() const
{
	return PatrolPoints;
}

Here is PatrolRoute.h:

// Fill out your copyright notice in the Description page of Project Settings.

#pragma once

#include "Components/ActorComponent.h"
#include "PatrolRoute.generated.h"


UCLASS( ClassGroup=(Custom), meta=(BlueprintSpawnableComponent) )
class S05_TESTINGGROUNDS_API UPatrolRoute : public UActorComponent
{
	GENERATED_BODY()

public:
	TArray<AActor*> GetPatrolPoints() const;

private:	

	UPROPERTY(EditInstanceOnly, Category = "Patrol Route")
	TArray<AActor*> PatrolPoints;
		
	
};

D) DxDiag is attached.[link text][3]

I will also note that this isn’t restricted just to what blueprint you see on the screen, it can happen in any blueprint when I’m simply dragging a node connection from one place to another.

5

I also want to mention that after reloading the project after the crash, the issue went away, I continued hooking up the nodes as norma. It is completely random but is always in blueprint.

6

In addition, I also noticed in the editor I frequently get the following error displaying in the output log. I attached this as a txt file.

link text

7

Thank you for the additional information, however I have not been able to reproduce this issue on our end. Could you provide a sample project that exhibits the issue that you are seeing along with a set of steps to cause the issue in the provided project?

8

Here it is again. I attached a video that shows when it happens, and a dropbox link to my project. Different project, different engine version, same issue since UE 13, 14, 15, and now 16. Always happens when I’m in blueprint and dragging a node off of something. Doesnt matter which project either.

9

Hello ,

I ran a few tests with the information and project provided. However, this issue does not reproduce on our end. Could you download the zipped down project that was provided and insure that the issue still occurs? If it does do you have set of steps that will reproduce this issue with the project provided? Please be sure to include any small steps that may have been over looked.

10

Unfortunately this still occurs, it only happens in blueprint, and is completely random. It is usually when I am pulling off a node and about to plug it in to another. Doesn’t matter which node.

This is leading me to believe that maybe this is a Windows issue? The engine crashes right after I click OK on the crash prompt.

Would it help if I included the crash report info for the next time it happens? I’ve submitted it dozens of times since this started happening.

11

Hello ,

I have run more tests with the information provided. However, I have not run into the issue that you are experiencing. It is possible that it could be an issue local to your machine. I will be closing this thread for tracking purposes. Without a reproducible test case I will not be able to write a report. However, if you or anyone else are able to provide a reproducible test case please feel free to reopen this issue and I will be happy to investigate further. All that’s needed to reopen this issue is to reply with more information.

12

Hello ,

We have not heard back from you in a few days, so we are marking this post as Resolved for tracking purposes. If you are still experiencing the issue you reported, please respond to this message with additional information and we will follow up.

Thanks,