I was looking at the World CUP app from the Eighth Edition of CoreData by Tutorials and overnight my compuer updated Xcode to 26.0, now I am getting 10 of these messages:
Conformance of ‘NSManagedObject’ to ‘Sendable’ in unavailable in IOS. Is this an Xcode 26 bug or is there an easy fix?
Hello,
Turn Off Strict Concurrency Checking (Best temporary fix)
If you’re not ready to fully adopt Swift 6 strict checking, you can opt out for now:
In your Build Settings:
Look for: Swift Concurrency Checking
Set it to: Minimal or Targeted (instead of Complete)
Alternatively, add this flag:
-Xfrontend -disable-availability-checking
- Use @unchecked Sendable if you know what you’re doing
If you really must pass around an NSManagedObject in a concurrent context (not recommended unless you’re sure), you can do:
extension MyManagedObject: @unchecked Sendable {}
It’s not a bug — Xcode 26 enforces stricter Swift concurrency rules. NSManagedObject isn’t Sendable, and now you’re mywisely getting warnings or errors. You can usually fix it by marking affected code with @unchecked Sendable or refactoring to avoid crossing concurrency boundaries with NSManagedObject.