I am currently developing two macOS applications, and both of them were bug free until about 9:00 PM on Tuesday, October 4 when both applications all of a sudden were unable to be compiled due to error: Task failed with exit 1 signal 0. Both apps point to this file: libswiftAppKit.dylib inside their respective debugging directories (which are different). I have tried deleting the file from the debugging directory, I have tried to reset my keychain, I have setup a provisioning profile, I have cleaned both projects many times, and I have restarted my computer twice.
Edit: It is still not working, and I have uninstalled and reinstalled Xcode.
Edit 2: I have reinstalled macOS Sierra and the same error is on both of my apps.
Why is this happening (also, why is it "all of a sudden" for two separate apps)? How do I fix it?
FINALLY FIGURED IT OUT!
After many many hours, I finally went back into my developer account's certificates/profiles and deleted everything and recreated each one. Installed them onto my Mac, and now it is finally working. Still don't understand why all of a sudden this happened, but that was my solution.