There is bug in Xcode 8 that has not yet been fixed as of Xcode 8.2.1. If you running macOS Sierra you might find that Xcode hangs if you try to open a project, for example via Finder or the open command. The original bug report was filed as rdar://29319747 which mine was closed as a duplicate of.
Rick Ballard, Xcode Software Engineering Manager at Apple, helped me find the reason for this weird issue. I provided a sample and spindump and from these he was able to determine that it was a case of RTFM. 🙂
@Cocoanetics Thanks! This is the iCloud Drive hang documented in release notes (28212905). Recommend not storing projects in iCloud Drive.
— Rick Ballard (@rballard) December 27, 2016
Subsequently, upon reviewing the mentioned Xcode 8 release notes, I found not one but two issues with iCloud folders:
- When an Xcode project is stored in iCloud Drive, Xcode does not automatically detect iCloud Drive sync conflicts for projects or for files involved in the build. Note that the Documents and Desktop folders can be stored in iCloud Drive on macOS 10.12. (18161353)
- Opening Xcode projects and workspaces stored in iCloud Drive, or changing source control branches for an open workspace or project stored in iCloud Drive, may sometimes cause Xcode to hang. Note that in macOS 10.12, your Documents and Desktop folders may optionally be iCloud Drive locations. (28212905)
Up until this point I was keeping all my projects in ~/Documents/Projects. But since I want to make use of iCloud folders, yet not have Xcode being hanging itself every time I open one, I followed Rick’s advice: I moved all my projects to just ~/Projects.
iCloud folders are only available for Documents and Desktop, so any other location besides those not affected by this Xcode bug. I have not seen any other hanging since I moved the projects to the new place on all my machines.
Also published on Medium.
Categories: Bug Reports