Environment:
- Xcode 27.0 (27A266a), Mac App Store
- macOS 27.2 beta 1 (26B5086k)
- MacBook Pro M3 Max, 48 GB (Mac15,9)
Xcode crashes 100% of the time the moment I start typing a new variable inside a struct in the source editor. Building, running and debugging all work fine — the crash only happens on keystroke in the editor.
Crash log points to CoreML predictive code completion: EXC_BAD_ACCESS (SIGBUS) on thread MLSymbolPopularity.workQueue -> Espresso::inner_product_kernel_cpu::get_biases() -> CodeCompletionModel.init -> MLSymbolPopularity.loadModelIfNeeded
So the Espresso/CoreML runtime in macOS 27.2 beta 1 crashes while loading the predictive-completion model.
Tried, none fixed it:
- "Display code predictions" -> Never
- "Display code completions while typing" -> Manually
- defaults write com.apple.dt.Xcode IDEPredictiveCodeCompletionEnabled -bool NO
- Cleared DerivedData / Xcode caches
- Installed the full 2.25 GB model via Settings > Components (still crashes)
Not in the beta 1 "Known Issues". Filed: FB24823899 (Core ML, with two .ips crash logs + repro steps). Anyone else seeing MLSymbolPopularity here?
Thanks for reporting this.
This is a known issue that has been documented in the Release Notes.
You can turn off enhanced code completion ranking with the following preference:
defaults write com.apple.dt.Xcode CodeCompletionAssetsToLoad /dev/null