[4.6] Updating Project causes crash when opening UMG Widgets

Development Programming & Scripting
1

##Branch:
Binary/Launcher

##Build version:
4.6

##Detailed description of the issue:

When updating a 4.5.1 project to 4.6, UMG widgets get compile errors (not warnings) - opening the widget to check the error crashes the engine.

Playing the game also crashes the engine.

This did NOT happen when I tested the 4.6 preview.

Update : I opened the 4.5.1 version again and checked all UMG functions to PURE - which was the cause of the compile errors in 4.6. I then opened the updated 4.5.1 version again in 4.6 as a copy - this did not solve the issue.

Update : Some widgets do open without crash, so there is definitely something causing the crash with specific blueprints in 4.6.

Update : Tested with a brand new clone of the project which didn’t use source control (I’ve had perforce cause issues in the past) but this didn’t have any effect. So perforce isn’t the issue.

Update : Custom Fonts are not the issue

##Repro Steps

Action 1: Update project from 4.5.1 to 4.6

Action 2: Open a UMG widget

Action 3: Crash

Additional Information

##System Specs:

  • Windows 8.1
  • AMD FX 8350
  • AMD 7970
  • 16GB DDR3 RAM
  • 2x 7200RPM HDDs in Raid-0
2

Hello Kenomica,

First off, thank you for the formatting of your issue. I updated an older project to see if I could get it to crash. I was unable to do so.

  1. Do you know if there were any other small steps that you may have taken to result in the crash?
  2. Can you cause the crash with a clean project (with just a widget and one that is upgraded from 4.5.1 to 4.6)?
  3. If this is successful could you provide the steps that you used to do so?
3

hi,Kenomica! the problem is when you try to open a widget, engine crash, right? did you closed the timeline window of the widget editor? in 4.5, if you close timeline window, you can’t open the widget any more, it’ll always crash.

4

I will do some tests today to see if I can reproduce it with clean projects. Thank you for your reply.

Some widgets do open without crash, so there is definitely something causing the crash with specific blueprints in 4.6. It does seem very random though. I have some very basic widgets that contain nothing but images and one button, and others that are very complex. Some basic ones crash the engine, as do some complex ones.

I made a quick project with the Third Person Template and made a few widgets, then converted to 4.6 and this works fine.

I also tested with a brand new clone of the project which didn’t use source control (I’ve had perforce cause issues in the past) but this didn’t have any effect. So perforce isn’t the issue either.

I have also set all fonts to default to see if custom fonts have caused it, since fonts had a big change in 4.6 - this did not fix the issue either. I’ve updated my main post with all these attempts.

Running out of things to test really…I’m stumped.

5

I’ll give that a go, thank you.

Update : just tested and the timeline is open on all widgets - so it had no effect. But thank you for the tip.

6

Thanks for the reply. Hopefully this is the case.

7

We also experienced crashes when opening UMG widgets with 4.6. Our problem is fixed by commit 2b87b029. I think this commit should be included in 4.6.1.

8

So, have you tried applying patch I linked on top of 4.6 to see if it resolves your issue?

9

I sadly have no experience with VS or building UE4 from source - so I’ve not been able to do so.

Unless any more support or information comes from this post, I am waiting for 4.6.1 to hopefully fix it.

10

Hello Kenomica,

I have a very technical source of information on how to merge certain commits to your project if you would be interested in taking a look. I hope this helps.

11

Thanks - it looks like the commit did fix it, since 4.6.1 completely fixed the issue!

12

4.6.1 released today and completely fixed the issue!