A strange issue with JUCE and XCode

Suddenly in my current Basic Plugin project, classes from the juce library have suddenly stopped linking correctly. I tried a fresh project from the Projucer and I am seeing the same bizarre issue!

No matching constructor for initialization of 'juce::AudioProcessorEditor' category:10

Is now showing up on both the current project and the fresh install. Also, from before on this version of Juce (6.0.1), if I enable including use namespace juce it causes strange errors. Is this something that is a problem with XCode? any suggestions on how I can track down what’s going on with these issues?

Usually there are further notes to the error message in Xcode, or better in the compiler log if you go to the right view in Xocde. they usually help