Console:

dyld: Symbol not found: ___chkstk_darwin
  Referenced from: /private/var/containers/Bundle/Application/6A606806-B567-4237-9B63-561126BF5E96/Appname.app/Frameworks/libswift_Concurrency.dylib (which was built for iOS 13.0)
  Expected in: /usr/lib/libSystem.B.dylib
 in /private/var/containers/Bundle/Application/6A606806-B567-4237-9B63-561126BF5E96/Appname.app/Frameworks/libswift_Concurrency.dylib

the app is running smoothly in the simulator with iOS 12.4

I tried making libswift_Concurrency.dbt optional. It did not stop the app from crashing.

CodePudding user response：

I encountered the same issue today, the issue was weird because everything just worked well before today. After some checks, I found that my system automatically updated Xcode from 13.1 to 13.2 last night. The Xcode 13.2 Release Notes shows that Xcode 13.2 has a compiler issue about libswift_Concurrency.dylib library, and it provides a Workaround method to resolve, but I found out the method doesn't work for me after I tried it.

I still don't know the reason which causes this issue, but I did make my project run on my iphone6 again by rollback Xcode to the version of 13.1 .

If your issue also caused by the update of Xcode, you can try this method. Download here: Xcode13.1

CodePudding user response：

You probably installed Xcode 13.2 from the App Store. Don't. There are bugs in that version. Go to developer.Apple.com and download Xcode directly from there.