Framework to XCFramework not working if the Framework is a bit more complex

Hi,

I'm trying to convert a "regular" FAT Framework to a XCFramework to make later use of it in the Swift-Package Manager (SPM).

This process works with very simple framework which has just a struct with one string property and a function.

But when I'm try to convert a more complex framework, like SwiftyBeaver, I get a kinds of weird errors as soon as I try to import the XCFramework in my project.

The error message in the Xcode-IDE is:

"Failed to build module 'SwiftyBeaver' for importation due to the errors above; the textual interface may be broken by project issues or a compiler bug"

When I look into the arm64-apple-ios.swiftinterface - file I see all kind of weird declerations like:

open class BaseDestination : Swift.Hashable, Swift.Equatable {
  open var format: Swift.String
  open var asynchronously: Swift.Bool
  open var minLevel: SwiftyBeaver.SwiftyBeaver.Level
  open var levelString: SwiftyBeaver.BaseDestination.LevelString
  open var levelColor: SwiftyBeaver.BaseDestination.LevelColor
  open var calendar: Foundation.Calendar

and error messages like: SwiftyBeaver' is not a member type of class 'SwiftyBeaver.SwiftyBeaver'

Which is very likely true.

These are the commands I execute to create the XCFramework:

xcodebuild archive -scheme SwiftyBeaver -destination "generic/platform=iOS" -archivePath /work/SwifyBeaver.xcarchive SKIP_INSTALL=NO BUILD_LIBRARY_FOR_DISTRIBUTION=YES

ARCHIVE SUCCEEDED

and then:

xcodebuild -create-xcframework -framework /work/SwifyBeaver.xcarchive/Products/Library/Frameworks/SwiftyBeaver.framework -output ./SwiftyBeaver.xcframework

both commands succeed but when I add the XCFramework to my XCode-Project and import the module I get error message - stated above:

"Failed to build module 'SwiftyBeaver' for importation due to the errors above; the textual interface may be broken by project issues or a compiler bug"

I'm using XCode 13.3.1 and xcodebuild -version gives me this output:

objc[16246]: Class AppleTypeCRetimerRestoreInfoHelper is implemented in both /usr/lib/libauthinstall.dylib (0x201a47458) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x1040184f8). One of the two will be used. Which one is undefined.
objc[16246]: Class AppleTypeCRetimerFirmwareAggregateRequestCreator is implemented in both /usr/lib/libauthinstall.dylib (0x201a474a8) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x104018548). One of the two will be used. Which one is undefined.
objc[16246]: Class AppleTypeCRetimerFirmwareRequestCreator is implemented in both /usr/lib/libauthinstall.dylib (0x201a474f8) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x104018598). One of the two will be used. Which one is undefined.
objc[16246]: Class ATCRTRestoreInfoFTABFile is implemented in both /usr/lib/libauthinstall.dylib (0x201a47548) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x1040185e8). One of the two will be used. Which one is undefined.
objc[16246]: Class AppleTypeCRetimerFirmwareCopier is implemented in both /usr/lib/libauthinstall.dylib (0x201a47598) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x104018638). One of the two will be used. Which one is undefined.
objc[16246]: Class ATCRTRestoreInfoFTABSubfile is implemented in both /usr/lib/libauthinstall.dylib (0x201a475e8) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x104018688). One of the two will be used. Which one is undefined.
Xcode 13.3.1
Build version 13E500a

Any idea how to solve this problem?

Thanks in advance!

Best Regards,

Frank