[5.3.5 fixed] Canvas.Sort in 5.3.4p6 Android IL2CPP taking several seconds

Hi, I'm currently working on a rather big mobile game project and I have some weird issues with the Canvas sorting, but only when built with IL2CPP for Android! I'm about to file a bug report but I need to get the clearance from my client first because I guess I won't be able to put a isolated reproduction case together.

So when I perform a specific action inside the game on a device, the frametime will spike horribly (>12 SECONDS) and this is what I see for the profiling timeline in those moments:



There are multiple canvas sorting jobs posted and each of them takes around 3 seconds to complete. Does anyone maybe know where I could look what could be the connection between IL2CPP and the Canvas sorting? Is the UnityUI library put through IL2CPP as well and may exhibit special IL2CPP bugs in this case?
I also don't have the option to try to reproduce this on iOS IL2CPP, so I don't know if it's related to android specifically or to IL2CPP.

 

Just to follow up - the issue seems to be fixed in 5.3.5! I couldn't reproduce it anymore.