In Swift 6 a simple setup of the Metal commandQueue command buffer causes an app crash that has no diagnostic feedback on the cause.
(See Metal com.Metal.CompletionQueueDispatch crash in Swift 6)
The direct cause of the crash is apparently SE-0423 which by design crashes the app.
The SE states: “ adoption of this feature has runtime implications, because actor-isolated code called incorrectly from preconcurrency code will crash instead of race.”
Without an error message on the reason for the crash, and no knowledge that there is a hidden assert, I had no means to debug or fix the problem. To me it looked like Swift 6 was unstable and the app would have to stay at Swift 5.
The goal of Swift 6 is to prevent difficult to debug errors/crashes, but in this case Swift 6 was causing a difficult to debug crash in code which historically has been without problems.
Reviewing the other cited threads shows that other developers are also hitting the same problem in not knowing how to fix a Swift 6 crash from this SE.
A minimal help would be to cite the SE-0423 in the crash. That alone would have given me a starting point clue about the reason and well as good hints for a solution. Even better would be info about the specific context and alternative solutions