Xcode 10 framework dependency cycle with itself

On Xcode 10 I'm getting this build error with one of my frameworks when I do an incremental build (clean builds work):

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:-1: Cycle inside LoggingSharedFramework; building could produce unreliable results.
Cycle details:
→ Target 'LoggingSharedFramework' has a command with output 'blablabla/Build/Products/Debug-iphonesimulator/LoggingSharedFramework.framework/LoggingSharedFramework'
○ Target 'LoggingSharedFramework' has link command with output 'blablabla/Build/Intermediates.noindex/blablablah/Debug-iphonesimulator/LoggingSharedFramework.build/Objects-normal/x86_64/LoggingSharedFramework'

• The framework has no target dependencies
• The Headers phase is before Compile Sources
• I have gone through every file and made sure that there are no imports grabbing files outside of LoggingSharedFramework (other than Cocoa stuff)

This error makes no sense to me. What is the actual cause? How can I figure out what is introducing the cycle? How can I fix the cycle?

from Xcode 10 framework dependency cycle with itself