App can't debug on iOS 26 device, but can on iOS 18

It seems to be trying to include XCTest, but its no where in the build phases or frameworks? Anyone seen this issue?

I agree that's the likely issue here. In addition to looking in places like the Linked Libraries section of build settings, look in your Build Settings if it's been added to a build setting there. And finally, check the organization of your scheme, under the Build tab. Compare the actions in that tab to that of a brand new project, and which are enabled and not enabled for different target types and actions.

— Ed Ford,  DTS Engineer

This is a strange one as XCTest is nowhere to be found anywhere in the build settings or schema, and a fresh project installs fine, even with similar dependencies. Plus, from Xcode 26 it will build and install fine on an iOS 18 device and the simulator. So its something with this Xcode project and iOS 26 phones.

Are you able to share your project "as is" with us to look at? If it's in a public place, you can share a link to it here. If you need to keep it private but are willing to share it with us to figure out where this is coming from, you can open a code-level support request, and we can facilitate a private file transfer that way.

— Ed Ford,  DTS Engineer

I'm having the same problem with iOS 26 phone simulators on Xcode Beta 3 but not on iOS 18.5 simulators.

Failed to iterate on macho slices for input file: /Users/asiergmorato/Library/Developer/CoreSimulator/Devices/D8BDCB2C-690F-4D08-A87D-AC05851CD89F/data/Library/Caches/com.apple.mobile.installd.staging/temp.AnaSyj/extracted/FitWoody.app/Watch/FitWoody-Watch.app/Frameworks/powersync-sqlite-core.framework/powersync-sqlite-core

App installation failed: No se puede instalar FitWoody
Domain: IXUserPresentableErrorDomain
Code: 1
Failure Reason: Inténtalo de nuevo más tarde.
Recovery Suggestion: Failed to iterate on macho slices for input file: /Users/asiergmorato/Library/Developer/CoreSimulator/Devices/D8BDCB2C-690F-4D08-A87D-AC05851CD89F/data/Library/Caches/com.apple.mobile.installd.staging/temp.YEGeGW/extracted/FitWoody.app/Watch/FitWoody-Watch.app/Frameworks/powersync-sqlite-core.framework/powersync-sqlite-core
User Info: {
    DVTErrorCreationDateKey = "2025-07-13 15:39:48 +0000";
    IDERunOperationFailingWorker = IDELaunchiPhoneSimulatorLauncher;
    SimCallingSelector = "installApplication:withOptions:error:";
}
--
No se puede instalar FitWoody
Domain: IXUserPresentableErrorDomain
Code: 1
Failure Reason: Inténtalo de nuevo más tarde.
Recovery Suggestion: Failed to iterate on macho slices for input file: /Users/asiergmorato/Library/Developer/CoreSimulator/Devices/D8BDCB2C-690F-4D08-A87D-AC05851CD89F/data/Library/Caches/com.apple.mobile.installd.staging/temp.YEGeGW/extracted/FitWoody.app/Watch/FitWoody-Watch.app/Frameworks/powersync-sqlite-core.framework/powersync-sqlite-core
--
Failed to iterate on macho slices for input file: /Users/asiergmorato/Library/Developer/CoreSimulator/Devices/D8BDCB2C-690F-4D08-A87D-AC05851CD89F/data/Library/Caches/com.apple.mobile.installd.staging/temp.YEGeGW/extracted/FitWoody.app/Watch/FitWoody-Watch.app/Frameworks/powersync-sqlite-core.framework/powersync-sqlite-core
Domain: MIInstallerErrorDomain
Code: 73
User Info: {
    FunctionName = MIMachOFileIterateImageVersions;
    SourceFileLine = 132;
}
--
parse_macho_iterate_slices failed for /Users/asiergmorato/Library/Developer/CoreSimulator/Devices/D8BDCB2C-690F-4D08-A87D-AC05851CD89F/data/Library/Caches/com.apple.mobile.installd.staging/temp.YEGeGW/extracted/FitWoody.app/Watch/FitWoody-Watch.app/Frameworks/powersync-sqlite-core.framework/powersync-sqlite-core
Domain: NSPOSIXErrorDomain
Code: 0
Failure Reason: Undefined error: 0
User Info: {
    FunctionName = MIMachOFileIterateImageVersions;
    SourceFileLine = 132;
}
--

Event Metadata: com.apple.dt.IDERunOperationWorkerFinished : {
    "device_identifier" = "D8BDCB2C-690F-4D08-A87D-AC05851CD89F";
    "device_model" = "iPhone17,1";
    "device_osBuild" = "26.0 (23A5287g)";
    "device_osBuild_monotonic" = 2300528706;
    "device_os_variant" = 1;
    "device_platform" = "com.apple.platform.iphonesimulator";
    "device_platform_family" = 2;
    "device_reality" = 2;
    "device_thinningType" = "iPhone17,1";
    "device_transport" = 4;
    "dvt_coredevice_version" = "477.25";
    "dvt_coredevice_version_monotonic" = 477025000000000;
    "dvt_coresimulator_version" = 1043;
    "dvt_coresimulator_version_monotonic" = 1043000000000000;
    "dvt_mobiledevice_version" = "1818.0.1";
    "dvt_mobiledevice_version_monotonic" = 1818000001000000;
    "launchSession_schemeCommand" = Run;
    "launchSession_schemeCommand_enum" = 1;
    "launchSession_targetArch" = arm64;
    "launchSession_targetArch_enum" = 6;
    "operation_duration_ms" = 23567;
    "operation_errorCode" = 1;
    "operation_errorDomain" = IXUserPresentableErrorDomain;
    "operation_errorWorker" = IDELaunchiPhoneSimulatorLauncher;
    "operation_error_reportable" = 1;
    "operation_name" = IDERunOperationWorkerGroup;
    "param_consoleMode" = 1;
    "param_debugger_attachToExtensions" = 0;
    "param_debugger_attachToXPC" = 1;
    "param_debugger_type" = 3;
    "param_destination_isProxy" = 0;
    "param_destination_platform" = "com.apple.platform.iphonesimulator";
    "param_diag_MainThreadChecker_stopOnIssue" = 0;
    "param_diag_MallocStackLogging_enableDuringAttach" = 0;
    "param_diag_MallocStackLogging_enableForXPC" = 1;
    "param_diag_allowLocationSimulation" = 1;
    "param_diag_checker_mtc_enable" = 1;
    "param_diag_checker_tpc_enable" = 1;
    "param_diag_gpu_frameCapture_enable" = 0;
    "param_diag_gpu_shaderValidation_enable" = 0;
    "param_diag_gpu_validation_enable" = 0;
    "param_diag_guardMalloc_enable" = 0;
    "param_diag_memoryGraphOnResourceException" = 0;
    "param_diag_queueDebugging_enable" = 1;
    "param_diag_runtimeProfile_generate" = 0;
    "param_diag_sanitizer_asan_enable" = 0;
    "param_diag_sanitizer_tsan_enable" = 0;
    "param_diag_sanitizer_tsan_stopOnIssue" = 0;
    "param_diag_sanitizer_ubsan_enable" = 0;
    "param_diag_sanitizer_ubsan_stopOnIssue" = 0;
    "param_diag_showNonLocalizedStrings" = 0;
    "param_diag_viewDebugging_enabled" = 1;
    "param_diag_viewDebugging_insertDylibOnLaunch" = 1;
    "param_install_style" = 2;
    "param_launcher_UID" = 2;
    "param_launcher_allowDeviceSensorReplayData" = 0;
    "param_launcher_kind" = 0;
    "param_launcher_style" = 0;
    "param_launcher_substyle" = 0;
    "param_lldbVersion_component_idx_1" = 0;
    "param_lldbVersion_monotonic" = 170300260101;
    "param_runnable_appExtensionHostRunMode" = 0;
    "param_runnable_productType" = "com.apple.product-type.application";
    "param_testing_launchedForTesting" = 0;
    "param_testing_suppressSimulatorApp" = 0;
    "param_testing_usingCLI" = 0;
    "sdk_canonicalName" = "iphonesimulator26.0";
    "sdk_osVersion" = "26.0";
    "sdk_platformID" = 7;
    "sdk_variant" = iphonesimulator;
    "sdk_version_monotonic" = 2300528704;
}
--


System Information

macOS Version 15.5 (Build 24F74)
Xcode 26.0 (24179.3) (Build 17A5276g)
Timestamp: 2025-07-13T17:39:48+02:00

I want to separate the components from the different contributors in this thread, as the underlying issue is not the same. @ethanrkaplan started this thread with an error message that points to a system framework, XCTest. And as he reports, there was an old build of their app involved, and removing at resolved this issue.

The error message provided by @asiergmorato and also @anders.u point to libraries frameworks included by their apps, not Apple system frameworks, and so have a different set up and resolution to look at here.

While I can't comment on @asiergmorato's circumstances more fully, as all we have is the error message here, @anders.u went ahead and opened a bug report (thank you!), so I have more information for their situation. @anders.u, you attached an XCFramework to your report that is a static framework, with the following bundle structure (edited for clarity):

SomeKit.xcframework
├── Info.plist
├── ios-arm64
│   └── SomeKit.framework
│       ├── SomeKit
│       ├── Headers -> Versions/Current/Headers
│       ├── Info.plist
│       ├── Modules
│       │   └── module.modulemap
│       ├── Resources -> Versions/Current/Resources
│       └── Versions
│           ├── A
│           │   ├── SomeKit
│           │   ├── Headers
│           │   │   └── <Files not listed for this forums post>
│           │   └── Resources
│           │       └── Info.plist
│           └── Current -> A
└── ios-arm64_x86_64-simulator
    └── SomeKit.framework
        ├── SomeKit
        ├── Headers -> Versions/Current/Headers
        ├── Info.plist
        ├── Modules
        │   └── module.modulemap
        ├── Resources -> Versions/Current/Resources
        └── Versions
            ├── A
            │   ├── SomeKit
            │   ├── Headers
            │   │   └── <Files not listed for this forums post>
            │   └── Resources
            │       └── Info.plist
            └── Current -> A

This is clearly intended to be for iOS and the simulator, based on the folders ios-64 and ios-arm64_x86_64-simulator. However, the structure of the .framework bundles are for macOS frameworks. Note the file system links represented by Headers -> Versions/Current/Headers, and the contents of the Versions directory. Neither of those elements are supported on iOS — Placing content in a bundle is the authority on how framework bundles should look — so there's something wrong with how these framework is being built.

Where you go from here depends on the provenance of this framework. If you're getting this from a vendor, you should contact their support and ask that they fix their framework. And if you're building this framework yourself (or perhaps another team in your company is building it) out of Xcode, then I recommend you start a brand new thread on the forums to help iron out issues with how this framework is built.

— Ed Ford,  DTS Engineer

@DTS Engineer Ed, Thank you for the comment. With your help I managed to resolve the issue and can ask the provider to correct their delivery.

I modified the xcframework bundle to create a structure as follows

SomeKit.xcframework
├── Info.plist
├── ios-arm64
│   └── SomeKit.framework
│       ├── SomeKit
│       ├── Headers
│       │   └── <Files not listed for this forums post>
│       ├── Info.plist
│       └── Modules
│           └── module.modulemap
└── ios-arm64_x86_64-simulator
    └── SomeKit.framework
        ├── SomeKit
        ├── Headers
        │   └── <Files not listed for this forums post>
        ├── Info.plist
        └── Modules
            └── module.modulemap

Thanks, Anders