NSBundle MetalTools.framework/ principal class is nil because all fallbacks have failed

I am seeing the same issue since moving up to the latest Xcode and iPadOS levels

Would be nice with a "log noise tracker". It seems like something always manages to sneak in.

I have the same error in a newly created project.

macOS 15.0.1

Xcode 16.0 (16A242d)

Is this actually triggering a failure? Or are you just worried about the log message? If it’s the latter, see On Log Noise.

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Quinn “The Eskimo!” @ Developer Technical Support @ Apple
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It’s better if you reply as a reply; it’s easy to miss comments. See Quinn’s Top Ten DevForums Tips for this and other titbits.

I've got same issue and also find the Bundle.main.url(forResource:withExtension:) does not work anymore.

Is this specifically related to Metal? Or just in general?

Because if you’re having a general problem with Bundle, I recommend that you start a new thread for that. Put it in App & System Services > General and tag it with Foundation so that I see it.

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

I'm having the same issue, I'm building a macOS menu bar app and when I switch to use the menu bar extra it does not specifically let me use Textfield or TexEditor but everything else works

I’ve been encountering this same error since Xcode 16. To compile successfully, I have to do a clean build every time—even though it’s just a simple menubar app.

1. Bought a brand new Mac.
2. Installed Xcode via App store (2024-12-09) Dec 2024.
3. Followed the official tutorial for SwiftUI here: https://developer.apple.com/tutorials/swiftui/creating-and-combining-views
4. At the bit where it wants to demo live editing of the app, nothing happens (despite various attempts, key combos, going through google advice).
5. On finding the 'debug' app I can see this message displays when I try to do the 'live inspector edit' to change the string.

Can't find or decode reasons
Failed to get or decode unavailable reasons
NSBundle file:///System/Library/PrivateFrameworks/MetalTools.framework/ principal class is nil because all fallbacks have failed

1. I don't see the expected 'inspector dialog' the tutorial shows in the screen shot. Nothing happens (apart from this message showing).

Could this error be causing the issue of the inspector not showing up like it does in the tutorial?

Thanks!

PS: I am new to the platform, so sorry if I missed anything obvious.