Author Topic: Getting a tricky crash on iOS since upgrading to Unity 5.6.0p3 from 5.4  (Read 3254 times)

Hi there,

As the title suggests I'm getting a nasty crash exclusively on iOS since upgrading to 5.6.0p3 that's not producing any error messages in xcode.

I can only assume that it's an issue with substance integration since it crashes at the point where I'm either about to or during rebuilding of my procedural materials. I'll probably need to put together a repro project.

But in the meantime any advice on getting an error message in xcode or any news of others suffering similar issues would be greatly appreciated.

Many Thanks,


Hey andy.dys,

That certainly sounds odd. Especially since you receive no error messages.  :-\ If you do put together that repro project, can you send it my way so we can try to reproduce the crash on our end? Also include some of the substances you are having problems with, just in case. My email is:

Hi Keston,

Thanks for your response, so far I'm completely stumped. The app just freezes (locks up without hope of recovery) intermittently (i.e. not the first rebuild but anywhere between the 4th or 10th texture rebuild, so it's not 100% predictable)  I'm going to try rolling back to 5.5.3p2 to see if I get the same problem, might help pin point a change in the system that caused this bug to creep in.

Actually you might be able to help in this regard. Do you know any particular releases since 5.4 that had any major substance tweaks that would be worth me focusing on?

Thanks again for your support.


Ok, so far so good no errors or crashes in 5.5.3p3. I need to do some more tests but appears to be exclusive to 5.6 or a more limited number of the more recent 5.6 versions. I'll keep you posted.

Ok, tell a lie. I'm still getting issues in 5.5, they just seem to be less frequent. Same crash however, app freezes during texture rebuild. I went back to 5.4 and noticed generation was a lot more responsive/ quicker and there are no crashes, even after more extreme and heavy testing. There's definitely something wrong in 5.5/5.6 on iOS.
I also noticed that when I remove some hacks in my code to fix a bug introduced in 5.4 that there are still issues in 5.5 and 5.6 that were supposed to be resolved.
The bug I'm referring to is "Substance: Fixed SubstanceImporter.ExportBitmaps generated file names."
In 5.4 I have to create the materials on a surrogate game object that ultimately gets destroyed before running a search to find my generated textures and assigning them. Where as in 5.3 I could take them directly from each individual procedural material instance, nice and clean.
In 5.5 and 5.6 I can get away without using the surrogate but still have to use the search to find them which is strange.
Anyway I'm going to have to build a repro project to get to the bottom of what's going on. It will no doubt take me some time to remove all my proprietary assets and make sure I can reproduce the bug. So it might be a few weeks / month  before I can get around to it. In the meantime in order to remain productive I shall have to return to the relative safety of 5.4. :( Part time solo indie dev sucks when there are so many issues between versions. I guess it's unavoidable when there are so many parts and platforms to manage. Just when I thought I'd resolved all the other issues / alterations in 5.5 and 5.6.  ::)  :'(

Hey andy.dys,

Whenever you get around to building that repro project, send it to me so we can take a closer look. In the meantime, we'll look into it more on our end. I'm sorry I don't have any answers for you, but as you said, this seems to be a tricky crash.  :(

I'm having exact same issue with android and ios, build by unity 5.6.1p1.
Freeze, no error message, nothing.
But in my case, it works fine when I load substance asset from normal build.
The problem arise when I put my assets into assetBundle.
When using assetBundle, it just freezes when loading substance textures.
It might be different issue so I'm planning to try on 5.4.0.
If it's same issue, then 5.4.0 will might work.

Hey Sunny Kim 0,

Can you upload or email a repro project so that we can take a closer look at this? My email is

You mean 'repo' the whole unity project?
It's really big like 20GB. There is so many resources and my clue of the problem was if I set every substance as "Baked discard substance", the freezing problem disappears.

But I cannot use "Baked" option either. Because of below issue.
My diffuse specular normal etc.. has different resolution respectively, but everything gets to 512 size.

I'll try making a sample project that contains the problem. Much smaller project so that I can send you.
Last Edit: July 20, 2017, 03:45:55 am

Hey Sunny Kim 0,

Yeah a small project with the issue reproducible within it would be fantastic. :) No need to send the whole 20GB project.