Xcode bot failure: error: unable to spawn process (Argument list too long)

Xcode Version 10.1 (10B61)


Project consists of many (Swift + Objective-c) files.

Xcode bot fails to archive with following error: (Build succeeds)


error: unable to spawn process (Argument list too long)

** ARCHIVE FAILED **


Command failing:

/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swiftc -incremental


Project builds and archieves successfully on Xcode manually, but fails on bot.