same problem here, updating to from 13.3.1 to 13.4. 3 reboots, no relief. Next I'm going to wait a day and see. Isn't this what they invented @PROGRESS_METERS for?

I took my 20K app using SceneKit running on an Apple M1 and pruned it down to a 2 line program which fails. It runs on an x86 2013 MacBook pro. To duplicate, make a new CommandLine app and plonk the following lines down. import SceneKit let _ = SCNMatrix4Mult(SCNMatrix4Identity, SCNMatrix4Identity) It responds with Thread 1: EXC_BAD_ACCESS (code=1, address=0x20) I think this may be the same problem, and hope that it gets you closer to the problem. When I code matrix 4 multiply by hand, then I get a boundingBox bad address fault.

Same problem, filed bug report. Running Xcode 12.3, BigSur 11.1.

Happened to me too, updating to Xcode 12.1. I noted that when I restarted, It asked to update libraries. Then the bug was fixed.