Xcode 26.5 can't run apps on visionOS 27 and iOS 27 Beta 2

With Xcode Version 26.5 (17F42) apps can no longer be launched on a real Vision Pro once migrated to visionOS 27 Beta 2. At launch there is an EXC_BAD_ACCESS runtime error in an initialiser.

If you launch apps on a real iPhone/Ipad with OS 27 Beta 2 the program will stop before the end of its start, but there is no precise line with the error. Xcode just stop in assembly code in the debugger, in the init phase of Swift where it searches for which objects to instantiate at launch.

After investigating, the error comes from a debug setting from Xcode to show the stack trace.

To avoid the error when run from Xcode Version 26.5 (17F42) In Xcode, open Product > Scheme > Edit Scheme. Select the Run action in the sidebar, then open the Options tab. Find Queue Debugging and uncheck Enable backtrace recording.

If Queue debugging is enabled, then the program crashes when launched

It is useful to be able to run apps from the production Xcode to devices with 27 OSes in beta to be able to test that everything will work fine for new versions of apps released before OSes 27 release.

Thank you

A previous post was made but the cause was badly identified.

New Feedback including a sample code FB23384318

Answered by DTS Engineer in 895412022

I just wanna be clear that using Xcode 26 to run apps on appleOS 27 beta is not supported. Frankly, I’m surprised that you got as far as you did.

As a general guideline, Xcode doesn’t support running apps on platforms that were released after that version of Xcode was released. This isn’t universally true — for example, we regularly publish minor updates to the OS that don’t have a corresponding Xcode, and thus we go out of our way to make sure they work with the existing Xcode — but it’s a good general guideline and it’s always true for major releases.

It is useful to … test that everything will work fine for new versions of apps released before OSes 27 release.

That’s a worthy goal, but this is not the way to do it. If you don’t plan to publish an update that’s specific to appleOS 27, you can test your app in various ways:

  • Use appleOS 27 beta to download the app from the App Store.
  • Or, if you want to test a beta release of your app, do the same using TestFlight.
  • Use Xcode 26 to build your app, export it as a .ipa, and then install that using the Finder, Apple Configurator, and so on.

Share and Enjoy

Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

I just wanna be clear that using Xcode 26 to run apps on appleOS 27 beta is not supported. Frankly, I’m surprised that you got as far as you did.

As a general guideline, Xcode doesn’t support running apps on platforms that were released after that version of Xcode was released. This isn’t universally true — for example, we regularly publish minor updates to the OS that don’t have a corresponding Xcode, and thus we go out of our way to make sure they work with the existing Xcode — but it’s a good general guideline and it’s always true for major releases.

It is useful to … test that everything will work fine for new versions of apps released before OSes 27 release.

That’s a worthy goal, but this is not the way to do it. If you don’t plan to publish an update that’s specific to appleOS 27, you can test your app in various ways:

  • Use appleOS 27 beta to download the app from the App Store.
  • Or, if you want to test a beta release of your app, do the same using TestFlight.
  • Use Xcode 26 to build your app, export it as a .ipa, and then install that using the Finder, Apple Configurator, and so on.

Share and Enjoy

Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

I know in the past that various pre-release betas were broken in the current production Xcode, but were later fixed and ended up working fine.

Are you saying it's never been supported to simply run an app in debug from a production Xcode version to a pre-release iOS/iPadOS version?

Are you saying it's never been supported … ?

Yes.

Historically this would just fail at the first hurdle; that is, Xcode would display some sort of mysterious error trying to install the app. These days Xcode is more isolation from the app installation infrastructure — Core Device, Device Hub, and all that — so it seems that Xcode is able to install the app just fine, but then, as lAppliEnRose discovered, you run into other, more subtle, problems.

Share and Enjoy

Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

Xcode 26.5 can't run apps on visionOS 27 and iOS 27 Beta 2
 
 
Q