Constant crash in editor if I try to save/delete/compile anything or play

Development Programming & Scripting
1

Branch: 4.8.2 from the launcher

Build version: 4.8.2-2614606+++depot+UE4-Releases+4.8

Detailed description of the issue: Any time try to compile (and this includes already successfully compiled blueprints, because I don’t have any that are giving me any errors), save (blueprints/materials/the level/anything), delete (anything), or play in editor the editor crashes.

I’ve had similar issues going on since upgrading to 4.8.2 and each time I was able to look at the log and find the issue and fix it. Nothing works right now. The error is that my animation blueprint isn’t accessing the “My Char” variable correctly for whatever reason despite me changing nothing with it in the passed couple days. Previously I fixed the error by recompiling my character blueprint, but that doesn’t even work now (I just get the same crash with the same log if I try to recompile my character blueprint).

I tried verifying the engine, nothing was wrong there.

I tried using backups of my character and animation blueprint, but that didn’t help the issue at all, same error happening. I’ve even copied all the content to a new project and everything runs just fine (which is what I may have to end up doing, I just don’t feel like re-setting up my key binds at the moment, and I would like to figure this bug out as well).

What is weird is the crash started happening after I turned DFGI back on (I had it on for a while for testing, then turned it off for a couple days, then decided to switch it back on). Even weirder is that the DFGI wasn’t even working (despite me having everything set up correctly). I think something got corrupted in the project, but I have no idea what.
I have to say, 4.8.2 has been very buggy for me. The editor crashes every time I close it, I had compiling blueprints crash the editor as well despite getting no errors in the compile (and they would be successfully compiled when I re-opened the project), and I had saving and deleting content crashing the editor for no real reason.

Repro Steps

Action 1 Try to compile/save/delete anything or press play.

Happens EVERY time.

System Specs: Windows 7 Professional, i7 2600, 16GB ram, GTX680 2GB (this should not be the issue as I get 60-90FPS in editor when I play)

Below is the text file with the copied text from the crash report as well as a link to the crash dump it created.

Crash report from editor

If needed I can upload the project as well.

2

Hi DuncanT -

Thank you for your report. We will begin investigation into this issue as soon as possible. If we are unable to reproduce the problem, or need more information, we will follow up with some additional questions for you. Otherwise, we will post an ‘Answer’ once the issue has been logged in our bug database or we have a solution for it.

In the meantime, please be sure to review our suggestions for how to report a bug, and feel free to edit your post if you have additional information to provide:

Thank you -

Eric Ketchum

3

Hi DuncanT. -

From what you’ve posted it looks like there is something in the MyChar class that is causing the crash but the crash stack is a little generic currently. If at all possible can you share the project with us? If you can reproduce it in a blank project all the better, but if not you can post a link to the project here or to me directly in the Unreal Engine Forums -

Thank You

Eric Ketchum

4

I’ve tried adding all my content to a blank project and everything loads fine so it’s something in my current project. I’ll upload it at PM you shortly. Thanks.

5

Hi DuncanT -

Ok sit down this is going to be a long one. First, your project is actually generating two different and unrelated crashes. The DXGI crash is a known issue and according to my tests is only happening when you close the program which is on par with the known issue and should not be affecting your project other than an annoyance.

The second crash reporter references garbage collection. It took me a bit, but the cause of this crash is actually how you have the BP_MasterItem resizing your inventory array in the Construction Script. Essentially as you compile or Play your Character BP is referencing all the Child BPs which call the construction script numerous times. The issue is related to how the various BPs are attempting to allocate and garbage collect into the same memory slots.

You can clear up this crash by moving the Construction Script Behavior from the Master to each Child.

Thank You

Eric Ketchum

6

Hi Eric, I’m trying to move the construction script behaviour out of my master item BP, however, I still get the same crash when I try to compile anything. I tried completely deleting the construction script from the master and I still get the crash. I then did the same thing but also removed the construction script for my character and the crash still happens.

What was your process for changing things around to be able to compile with no crash?

Thanks,
Duncan

7

Actually I’ve got it now. Thank you so much for your help, I was getting really frustrated.

Out of curiosity, why was the construction script being called multiple times? I don’t quite understand why that would happen.

8

Hi DuncanT. -

The Parent’s Construction Script is always called when the Child’s BP is substantiated , so you have multiple Children each trying to run the same script.

Now saying that, we have been investigating this further and the crash you are experiencing has been noted in a slightly different way as UE-15940. So, we are looking into garbage collection behavior as well, but for now, at least we have you back in your project and working again.

Best of Luck -

Eric Ketchum

9

“The Parent’s Construction Script is always called when the Child’s BP is substantiated , so you have multiple Children each trying to run the same script.”

Ok so I knew they called the parent construction script, but if I’m understanding correctly, the children all call the script in the Master BP itself rather than a copy of it in the Child’s BP?

I’ve since added some script into the Master BP’s construction script (though now removed as it was unnecessary) and it was compiling just fine. However, the script was much simpler than what I had before (it was only setting a couple values).

To my point, if the children do indeed call the function on the Master BP itself rather than a copy, then perhaps the issue came about from having the branch in the construction script as some Child BPs would continue passed the branch while others would not?

I have no real clue though, I have 0 coding (C++ or otherwise) experience so I’m really just guessing (if it weren’t for blueprint I wouldn’t even be trying my hand at game development).

So yeah, sorry for keep dragging this on, I hope whatever the bug is get’s sorted out. But until then, yes, thank you for helping me get things back in working order.

Cheers,
Duncan