Xcode 12.2 beta 3 / Big Sur Beta 10 throw SIGCONT for SwiftUI app

Question

I've just 'upgraded' to the latest Big Sur – 11.0 Beta (20A5395g) – and Xcode betas – 12.2 beta 3 (12B5035g). When I try to run any SwiftUI based Mac App the program stops with a Thread 1: signal SIGCONT message. Sometimes I am able to continue (Ctrl Command Y), but others the program stops with the message Message from debugger: Terminated due to signal 19.

The Stack trace suggests the problem is in the ImageLoader.

I've tried reinstalling Xcode and clearing out it's cache's. The problem even manifests with a brand new project - i.e. it isn't related to my code,

Any ideas how I might trouble shoot this?

Answer 1

You can workaround the issue using a symbolic breakpoint.

Add a symbolic breakpoint with the following settings:

Symbol: _main
Module: dyld
Action: Debugger Command with the command process handle -n false -s false SIGCONT
Options: Check Automatically continue after evaluating actions

Answer 2

Workaround by choosing "Debug Process as Root" in Schema "Run" -> "Info"

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