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?
Graphical Debugger
RSS for tagDebug your app directly within the Xcode editor using Graphical Debugger.
Posts under Graphical Debugger tag
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After updating my system to macOS Tahoe 26.1 and Xcode 26.1, all breakpoints in my project fail to work. When I run the application in Debug mode, any enabled breakpoint (blue) immediately becomes disabled (grayed out) the moment the app launches. The application runs, but the debugger never stops.
This issue occurs in any location, including in the application's init() method, which should always be hit. This behavior suggests that the LLDB debugger is failing to attach to the process at launch or is being instructed not to enable breakpoints.
System Configuration:
Mac Model: MacBook Pro 14" (2021), Apple M1 Pro
macOS Version: Tahoe 26.1
Xcode Version: 26.1
Project Type: SwiftUI App for macOS
Troubleshooting Steps Performed (All Unsuccessful):
We have performed an extensive series of troubleshooting steps to resolve the issue, none of which have worked. These steps include:
Basic Project Cleaning:
Cleaned the build folder (Product > Clean Build Folder).
Deleted the entire DerivedData directory.
Deleted the project's xcuserdata folder.
Xcode & System Procedures:
Restarted Xcode multiple times.
Rebooted the Mac multiple times.
Reinstalled Xcode Command Line Tools using xcode-select --install.
Reset the Xcode path using sudo xcode-select --reset and sudo xcode-select -s /Applications/Xcode.app/Contents/Developer.
Forced an update of the system's shared cache with xcrun simctl runtime dyld_shared_cache update --all.
Project Build Settings Verification (for Debug configuration):
Build Configuration: Verified that the "Run" scheme is set to Debug.
Optimization Level: Confirmed it is set to No Optimization [-O0].
Debug Information Format: Confirmed it is set to DWARF with dSYM File.
Strip Swift Symbols: Confirmed it is set to No. (This was a new setting noticed after the Xcode update).
Enable Hardened Runtime: Attempted setting this to both Yes and No. The issue persists in both cases.
Validate Workspace: Confirmed it is set to Yes.
Code Signing:
Verified that "Automatically manage signing" is enabled with a valid team.
Manually deleted and re-created the "Apple Development" certificates via Xcode's Accounts settings.
Direct LLDB Testing:
Created a ~/.lldbinit file.
Using breakpoint list, confirmed that LLDB starts with "No breakpoints currently set," indicating that Xcode is likely not passing the breakpoints to the debugger.
Using settings set target.process.stop-on-entry true, confirmed that the app still does not stop on entry, suggesting the debugger is failing to attach to the process at all.
Conclusion:
Given that all standard and advanced troubleshooting steps have failed, and the issue started immediately after updating both macOS and Xcode to a non-public release (Tahoe 26.1 / Xcode 26.1), this appears to be a regression or a bug in the new development environment. The failure of stop-on-entry strongly suggests a fundamental issue with the debugger attachment process on this specific OS and Xcode combination.
Hello everyone,
In the current iOS version, changes in the "liquid glass" light shining effects can repeatedly be observed on older iPhone devices (12/13/14).
This change is often seen after the device is rebooted or after a SystemMemoryReset.ips (System Analysis Data).
It changes very often...
I'm not currently working on apps myself, but perhaps someone has ideas for the upcoming updates involving Liquid Glass.
(please also check the screenshots)
Hello there!
In one of my apps, I noticed that the view hierarchy debugger isn't working anymore inside Xcode 26. So I created a new project, to see if it's just my project or Xcode. With the new project, it didn't happen. What can I do here?
I already reported that issue. Here is the id of it: FB20605681
I'm using the WebGPU abstraction library wgpu to build an app using compute shaders that compiles to Metal (on macOS), and in certain patterns where it uses a staging buffer for initial data, the data is just total missing from the capture, breaking other workflows such as shader debugging or seeing the completed results in the final buffer.
I wrote up details including a repro project and screen shots of the issue at https://github.com/gfx-rs/wgpu/issues/8111 . Seems like an Xcode bug. Any ideas? I'm happy to help investigate further if I can.
Xcode 16.3 build on ios18.4 ,app can't launch. Then lost connection to the debugger .
but Xcode16.3 with ios18.3 can launch
XCode 26 beta 2 is taking more than 20 seconds to start AVCaptureSession when AVCaptureVideoDataOutput and AVCaptureAudioDataOutput are added. The problem occurs only during debugging and is clearly seen with Cinematic Capture sample code by Apple. I am using iPhone 14 Pro running iOS 26 beta 2 for reference.
How do I make std::string look like a char array? The expression viewer for std::strings is horrible.
After upgrading to iOS 18.4, I noticed that launching a debug build from Xcode becomes extremely slow. The same app with the same large debug binary (~1GB) launches normally on devices running iOS 18.3.
This issue seems specific to iOS 18.4, possibly related to the way the OS handles large debug binaries or symbols during the launch process.
Steps to Reproduce:
Connect an iPhone running iOS 18.4 to a Mac with Xcode.
Build and run an app using Xcode in Debug mode.
Observe the extended launch time.
Re-run the same process on another iPhone with iOS 18.3 — launch is fast.
Expected Result:
Debug launch should be fast and consistent across iOS versions.
Actual Result:
Debug launch is significantly slower on iOS 18.4 for large binaries (~1GB).
Environment:
Xcode version: 16.0
macOS version: 15.4
Device: iPhone [model]
iOS version: 18.4 (problematic), 18.3 (no issue)
i'v use own apple id run project with my mobile phone, but the xcode create a lot provisioning profile in same time(the pic only show a bit part)
Topic:
Developer Tools & Services
SubTopic:
Xcode
Tags:
Developer Tools
Xcode
Graphical Debugger
XCTest
The app stops on the breakpoint when "All Runtime Issues" is added. If I disable the breakpoint, the app runs normally. Is there a new project setting to avoid this breakpoint from being set. It does not appear to be a valid error. I am running Xcode 16.2. I edited the "Type" field in the breakpoint box. This occurs with the "System Frameworks" option only.
I'm working on an audio plugin, and when I set the target to VST3 instead of Standalone Plugin and check the "Debug Executable" box, I get this error:
Message from debugger: attach failed (Not allowed to attach to process. Look in the console messages (Console.app), near the debugserver entries, when the attach failed. The subsystem that denied the attach permission will likely have logged an informative message about why it was denied.)
I found this post, which seems to be about this same issue, and I followed the recommended solution:
I made sure CODE_SIGN_INJECT_BASE_ENTITLEMENTS is true and DEPLOYMENT_POSTPROCESSING is false. I also checked the entitlements on the .app using codesign -d --entitlements, and it returned:
[Key] com.apple.security.get-task-allow
[Value]
[Bool] true
This seems like it has the proper entitlements, but it is still breaking with the above error message when I clean and build. Any ideas?
When inspecting the geometry in Xcode's metal debugger, I noticed that the shown "frustrum box" didn't make sense. Since Metal uses depth range 0,1 in NDC space, I would expect a vertex that is projected to z:0 to be on the front clipping plane of the frustrum shown in the geometry inspector. This is however not the case. A vertex with ndc z:0 is shown halfway inside the frustrum. Vertices with ndc z less than 0 are correctly culled during rendering, while the geometry inspector's frustrum shows that the vertex is stil inside the frustrum.
The image shows vertices that are visually in the middle of the frustrum on z axis, but at the same time the out position shows that they are projected to z:0. How is this possible, unless there's a bug in the geometry inspector?
Network
Topic:
App & System Services
SubTopic:
StoreKit
Tags:
Subscriptions
App Store Connect
In-App Purchase
Graphical Debugger
Dear Sirs,
I'm searching for the most straightforward way to identify the root of a "Publishing changes from within view updates is not allowed, this will cause undefined behavior." warning. It is a complex SwiftUI project and I think there should be a better way than just try and error with disabling/removing and enabling/adding different screen elements to check if the warning still is shown. I tried to set a symbolic breakpoint for "os_log" in my XCode project and indeed this is triggered right before the warning appears but the callstack doesn't give me a direct hint to the part of my code which causes this warning. What would be the most direct way and is there something like an exception handler in such cases?
Thanks and best regards,
Johannes