Xcode 9.4 : unexpected service error: The Xcode build system has crashed

Question

I’m getting strange error while building project in Xcode 9.4

Build system information - unexpected service error: The Xcode build system has crashed. Please close and reopen your workspace.

I tried Xcode quit and reopen but that didn’t worked. Any solution?

Solution 1

Please clear derived data folder (located at ~/Library/Developer/Xcode/DerivedData) and restart the Xcode project.

Solution 2

This error usually happens between Xcode major versions. Apple usually claim their new build system is ** times faster than their previous version. If you see this error(I see this on changing Xcode9 to Xcode10 beta), you can always change it to the legacy build system. Here is how you can do this:

1. Open 'workspace settings'( it is now changed to 'Project Settings' if you are using Xcode10 or later) in the File Menu
2. Change build system to 'legacy'

Solution 3

I moved a lot of files all at once between folders, including nested folders. This error started happening. Nothing I did in regards to cleaning, purging derived data, or undoing the move operation would help.

What I did to help was: restore the previous version of the project file from source control and then re-add all the applicable new files to it. It was project file related. Deleting user data inside the project container did not help in my case. So as long as you use source control and can rollback the .xcodeproj, this may be an option.

Comments

[Jim Bergman]

In XCode 10 Workspace Settings is now called Project Settings.

[Salil Junior]

This resolves similar error issue that occurs when you downgrade from XCode 10.2 to XCode 10.1. Thanks.

[jhp]

Also solved the problem with XCode 11 Beta 4 for me. Thanks!

[vinnybad]

This iOS eng equivalent of "did you try turning it off and turning it back on" for Xcode :-). Sad but true! This fixes a lot of weird issues with Xcode.