Xcode 10 Error: Multiple commands produce for 'app' and 'appex'

Question

I got the recently discussed \"Xcode 10 Error: Multiple commands produce...\" error, but for the resulting app and appex file of my project. Does anyone have an idea what th

Answer 1

One of a possible issues causing the "Multiple commands produce" error may be several targets with conflicting module name. In my case I had a main application target and a notification service extension target with the same Product Module Name, so Xcode was trying to create two ModuleName.swiftmodule files, two ModuleName.swiftdoc files etc. Changing notification service extension module name fixed the problem.