'XCBBuildService quit unexpectedly' Xcode 9.3 (Swift 4.1)

Question

Ever since I've updated to Xcode 9.3 (current version), I started to get this message every time I try to add a new file to the project and often it requires me to reopen workspace several times for it to actually succeed at indexing.

Any suggestions on how to get rid of this issue will be highly appreciated!

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Additional information

• I found out that I now have this same issue in Xcode 8.3, though I've been working on it for the longest time ever and didn't encounter such an error ever before
• If I remember correctly, the first time I got this error was when I was working with Storyboards and an .xib file.
• This error happens during indexing
• Every new file causes re-indexing and every time it fails with this error
• Casual re-indexing (when there are no new files) does not cause this error to appear
• Reopening does eventually help but more often than not, it requires me to reopen it several times (same with relaunching Xcode)

Answer 1

I tried all kinds of things and ultimately cleared out cached/generated Xcode user application data via:

rm -Rf ~/Library/*/*Xcode*

And life was good again. Only one project kept failing, other sample projects still built and ran fine.