I’ve noticed a strange bug in Xcode 16 and Swift. When a preview is rendering and hasn’t finished yet and you run an app to debug, Xcode is launching two instances of the app. Has anyone else noticed this issue? If you let the preview finish rendering before running the app, this doesn’t happen. Very odd.
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I've updated my computer to Sequoia 15, Xcode 16 and now no matter what I do, I am unable to work with Swift UI previews.
I get this error each time I try to run the preview:
Failed to launch app in reasonable time
I have done:
Uninstall/Re-install Xcode
Deleted derived data
Deleted the simulator data
Used DevCleaner to remove all data related to Xcode
Searched all websites about this issue. ( Non shown a good solution )
Write this question on here.
If anyone has found a solution, please let me know how you fixed it.
The Foundation Models Framework stopped working after Xcode failed to download the "Predictive Code Completion Model".
What happened was on macOS Tahoe 26.0:
Downloaded and installed Xcode 26 Beta (17A5241e)
Worked with Foundation Models framework. Everything worked fine. ✅
Opened Xcode 16.4
This triggers the downloading of Predictive Code Completion Model which then fails.
Go back into Xcode 26 Beta, Foundation Models framework no longer works. ❌ Error: "Failed to find asset: com.apple.gm.safety_deny.input.code_intelligence.base.generic - no asset"
What I've tried or checked:
Reinstalling Xcode 26 Beta
Uninstalling both Xcodes and only installing Xcode 26 Beta
Checked available space on drive (over 300 GB free)
Restarted Mac
Restarted Xcode 26
Changed wifi networks
Turned on VPN
Deleted the Library > Developer > Xcode folder and reinstalled Xcode 26
Feedback Report
FB18208139: Can't download Predictive Code Completion Model - Xcode 26
Screenshots
Topic:
Developer Tools & Services
SubTopic:
Xcode
I am experiencing an issue where my Mac's speakers will crackle and pop when running an app on the Simulator or even when previewing SwiftUI with Live Preview.
I am using a 16" MacBook Pro (i9) and I'm running Xcode 12.2 on Big Sur (11.0.1).
Killing coreaudiod temporarily fixes the problem however this is not much of a solution.
Is anyone else having this problem?
When I compile my Xcode project using the xcodebuild command, I observe long incremental build durations. For example, compiling a new, empty project in Xcode only takes around one second. The same project takes 7 seconds to compile using the xcodebuild command. I've noticed that xcodebuild hangs at the "GatherProvisioningInputs" phase.
Steps to Reproduce:
Create a new Xcode project (iOS app template)
Build the project in Xcode with timing summary enabled
Build the same project from the command line with the following command:
time xcodebuild -destination 'platform=iOS Simulator,name=iPhone 15 Pro,OS=latest'
I would appreciate any insights or suggestions on how to improve the build times when using the xcodebuild command. Thank you in advance for your help!
Hello,
Switching Core Data Editor Style has been broken since Xcode 14 Beta 1. Although I can get by, it would be convenient to switch to the Graphical ER diagram style to "visually" study the model for an App.
Regards and Thank You,
John
Using xcode 26 with linker flag -ld_classic,get an error :
0 0x1042b9778 __assert_rtn + 160
1 0x1042bc560 ld::tool::SymbolTableAtom<x86_64>::classicOrdinalForProxy(ld::Atom const*) (.cold.3) + 0
2 0x1041f3da8 ld::tool::SymbolTableAtom<x86_64>::classicOrdinalForProxy(ld::Atom const*) + 172
3 0x1041f4c1c ld::tool::SymbolTableAtom::addImport(ld::Atom const*, ld::tool::StringPoolAtom*) + 140
4 0x1041f6500 ld::tool::SymbolTableAtom::encode() + 396
5 0x1041e83a8 ___ZN2ld4tool10OutputFile20buildLINKEDITContentERNS_8InternalE_block_invoke.413 + 36
6 0x182a95b2c _dispatch_call_block_and_release + 32
7 0x182aaf85c _dispatch_client_callout + 16
8 0x182acc478 _dispatch_channel_invoke.cold.5 + 92
9 0x182aa7fa4 _dispatch_root_queue_drain + 736
10 0x182aa85d4 _dispatch_worker_thread2 + 156
11 0x182c49e28 _pthread_wqthread + 232
A linker snapshot was created at:
/tmp/app-2025-06-13-215652.ld-snapshot
ld: Assertion failed: (it != _dylibToOrdinal.end()), function dylibToOrdinal, file OutputFile.cpp, line 5196.
clang++: error: linker command failed with exit code 1 (use -v to see invocation)
None of my existing apps (both in-AppStore and in-development) nor even a brand new WatchOS app can be installed to my Apple Watch. While using Xcode to build and deploy to my Watch, I get this:
”Waiting to reconnect to Apple Watch
Xcode will continue when the operation completes.”
However, this dialog persists and never completes.
I’m running all of the latest: MacOS 14 beta 4, Xcode 15 beta 5, Watch OS 10 beta 4, iOS 17 beta 4.
I’ve tried resetting my Watch (with “Erase All” option) and restarting the Mac, the phone and the watch.
Any help?
I have been working for a while now. Never encountered this issue. After accepting the invite from the organization. The organizations does not appear at developer apple account. But can see the organization at app store connect. Yes i have checked the account permissions. I have the admin role and developer role etc is checked everything is correct. This is not just me happening with my colleague as well.
With Xcode 26.0 beta 5 (17A5295f) when I run the following command
xcodebuild -downloadComponent metalToolchain
I get the following error:
xcodebuild[48851:12478851] Writing error result bundle to /var/folders/b_/g67r_tl557z244g20ncr_qmsd9wrz1/T/ResultBundle_2025-07-08_11-10-0012.xcresult
xcodebuild: error: Failed fetching catalog for assetType (com.apple.MobileAsset.MetalToolchain), serverParameters ({
RequestedBuild = 17A5295f;
})
I can't install the toolchain from the Xcode GUI also. Does someone know a workaround ?
I'm unable to download the Metal toolchain with Xcode. When trying to do it via the command line, I get the following:
> xcodebuild -downloadComponent metalToolchain -exportPath /tmp/MyMetalExport/
Beginning asset download...
2025-08-06 19:46:19.983 xcodebuild[1395:22024] Writing error result bundle to /var/folders/48/1k1jfsxn56zcs4qr_719rc1w0000gn/T/ResultBundle_2025-06-08_19-46-0019.xcresult
xcodebuild: error: Failed fetching catalog for assetType (com.apple.MobileAsset.MetalToolchain), serverParameters ({
RequestedBuild = 17A5295f;
})
From Console.app:
DVTDownloadsFetchAssetCatalog() complete assetType (com.apple.MobileAsset.MetalToolchain), options: (MADownloadOptions allowsCellular: 0 resourceTimeout: 60 canUseCacheServer: 0 discretionary: 0 disableUI: 0 sessionId: (null) additionalServerParams:{ RequestedBuild = 17A5295f; } allowsExpensiveAccess:1 requiresPowerPluggedIn: 0 prefersInfraWiFi: 1 liveServerOnly: -1 DownloadAuthorizationHeader: not present analyticsData: not present allowDaemonConnectionRetries: 0), result: (59), catalogError: (Download failed due to not being able to find the host. (Catalog download for com.apple.MobileAsset.MetalToolchain))
Note that I am online. I've tried restarting my computer and Xcode and using a different network.
Several app developers are struggling with the inability to provide a separate app icons that looks nice on older macOS versions while at the same time provide Icon Composer icons that look great on macOS Tahoe 26. An ability to provide separate icons is super important to those who have app icons that follow the curvature of the default icon borders (as the corner rounding radius is different for Sequia and Tahoe). Take a look at this for example:
https://github.com/ghostty-org/ghostty/issues/7564#issuecomment-3042061547
Question: Is there a definitive/recommended way to address this issue? How can a developer add a glass icon variant that looks good on Tahoe and provide a bitmap icon for older macOS versions?
Some background info:
Prior to Xcode 26 beta 4, one could add an App Icon to Assets to be used as app icon for legacy macOS versions (Sequia and older) and use a new Icon Composer icon (placed in the project root) for macOS Tahoe 26. Enabling "Include all app icon assets" under target settings ensured that older macOS versions would use the old app icons while Tahoe the new Icon Composer glass one.
Since Xcode beta 4 this technique no longer works. Xcode instead insists on populating Assets.car with Icon Composer generated variants, disregarding the App Icon provided in Assets. Although the App Icon in Assets makes its way to a .incs file in the app bundle's Contents/Resources folder, but that is not used by macOS anymore and is there for some compatibility purposes. The Assets.car file (which matters) only contains the variants generated by Icon Composer and does not contain the png icons provided in the Assets.
I try adding people as Sandbox Testers to my App, but Apple keeps saying that they already exist on the team, even though they're not.
It always show "A user with this email address already exists on the team"
It keeps happening with every address I try.
I failed to download Metal toolchain for Xcode Beta 5.
Downloading in Settings -> Components didn't work so I tried in terminal but didn't work too.
/tmp xcodebuild -downloadComponent metalToolchain -exportPath ~/Downloads
Beginning asset download...
2025-08-07 16:38:44.867 xcodebuild[91064:2244768] Writing error result bundle to /var/folders/bb/xtdv2kgn6rq3zxqs4f8f1j4w0000gn/T/ResultBundle_2025-07-08_16-38-0044.xcresult
xcodebuild: error: Failed fetching catalog for assetType (com.apple.MobileAsset.MetalToolchain), serverParameters ({
RequestedBuild = 17A5295f;
})
Topic:
Developer Tools & Services
SubTopic:
Xcode
Hi, since a while now, I've noticed that in Xcode 15 (beta 8), my iOS device running iOS 17 (latest beta), I can't seem to disable the setting "Connect via Network" in the Devices and Simulators window.
The controls are disabled, and stuck to 'on'.
I often also have issues with the 'Installing to device' step while development my apps, where a reboot of the iPad is required. My guess is that it gets stuck/confused how it is supposed to deploy and my network setup is a bit complicated due to VPN's, tight WiFi security etc.
Unpairing the device doesn't help with resetting this setting. After unpairing the top-right header (with the Take Screenshot controls etc...) even still shows the details of the unpaired device.
Anyone else has experienced this or know a solution.
Since upgrading my iPhone 13 Pro Max to iOS 26, apps have become nearly impossible to debug. The recent update to iOS 26.1 has made this even worse.
Going from app start to a fully rendered & responding screen takes <1 second on a Debug build when no debugger is attached, but with the debugger attached I get these times (measured manually with a stopwatch):
First render:
<1 second without debugger
5 seconds on USB debugger
30 seconds on wireless debugger
Data loaded from webserver and UI responding:
<1 second without debugger
19 seconds on USB debugger
5 minutes on wireless debugger!
Doing an online speed test reports 55 Mbps for the phone and 60 Mbps on the MacBook, so I doubt it's my WiFi.
Having a debugger attached used to make minimal difference on iOS 18, but the performance has tanked completely since the last major release. What happened?
I added a new liquid glass icon built with Icon Composer to my app. It works and looks great on iOS 26 but Xcode complains that required icon files for older versions are missing.
I still have the old AppIcon in my Asset Catalog but it seems like it's not being used.
How do I configure Xcode to use the old icons for iOS 18 and the new icon for iOS 26?
My company's app has a few widgets and a couple of them we do not want to show up on CarPlay due to safety concerns when iOS 26 releases. I understand Apple's recommended way to prevent users from using your widget in CarPlay is to use the .disfavoredLocations([.carPlay], for: [.systemSmall]), and this puts your widget in the 'Other' section of the widgets.
https://developer.apple.com/download/files/CarPlay-Developer-Guide.pdf
However, this .carPlay widget location is only available in Xcode 26, and our app cannot be built on Xcode 26 yet due to some build errors. We are able to fix those build errors in a separate branch, but we won't be doing our official release builds on Xcode 26 until it is out of beta, which is usually right before iOS 26 officially releases to general audiences. We release our app versions on a monthly cadence, so the version that will be out when iOS 26 comes out is already in testing.
Is there any existing way we can disable this widget on CarPlay so it does not appear to work when tapped? Currently, it opens our CarPlay app, but the CarPlay app does nothing with it. On the iPhone, when you tap the widget it opens our app and performs a function.
We don't wan't to disable it on the iPhone, just when it's on CarPlay. We don't have time before the app release to implement the same functionality on our CarPlay app. I haven't found any reliable way to detect if the widget is running in the CarPlay location versus the iPhone home screen.
Thanks in advance for any assistance.
Hello.
I'm seeing an inconsistent behavior where breakpoints I set in my (Swift) iOS app behave normally when I'm debugging on a device or on a simulator running iOS 17.x, but when I try using simulators of iOS 16 or 15 the breakpoints get ignored completely. I also observe that the breakpoints remain solid blue and do NOT adopt the dotted blue outline, as experienced by other users.
I've seen a few posts on here and on SO about the general issue of ignored breakpoints (with no conclusive answer AFAIK), but I haven't seen any where the behavior varies with the SDK being used. The behavior is repeatable and predictable (within the same app at least). I am not adding the breakpoints after building/running, and I'm sure the logic reaches the lines with the breakpoints (and again, whenever I switch to an iOS 17 simulator, execution does pause as expected with the exact same breakpoints).
Things I've tried and looked into:
Clean up project build folder
Delete and re-install simulators (iOS 16.4 and 15.5)
Deleted the entire derived data directory, as well as the CoreSimulator one.
Confirm the build configuration is Debug, and the "Debug executable" option is checked.
inspect various build flags mentioned in other posts:
{Swift compiler - Code generation - Optimization level - Debug: -0none; Debug information format: DWARF (I also tried DWARF with dSYM with no impact)}.
Most of my settings are on the plain vanilla/out of the box side, with only a couple of SPM dependencies, and I've been maintaining the same app for about 5 years and don't think I've come across this behavior before.
Currently using Xcode 15.1. Deployment target is 14.0.
Thank you.
I've just downloaded "Additional Tools for Xcode 13" after today's release, and installed "Network Link Conditioner.prefPane" on my macOS Big Sur 11.6 (20G165).
But it just don't work. Every time I try to open it an error appeared.
Dose the tool only support macOS Monterey which Xcode 13.0 (13A233) dose not support?
BTW, the workaround for me is using the tool in "Additional Tools for Xcode 12.5"...