Xcode 10 seems to break com.apple.commcenter.coretelephony.xpc

Running this in Terminal made it go away:

xcrun simctl spawn booted log config --mode "level:off"  --subsystem com.apple.CoreTelephony

Well it's working on both the simulator and device in Xcode 10.2.

  1. Add CoreTelephony.framework (Optional)

  2. Executing the following command in Terminal:

    xcrun simctl spawn booted log config --mode "level:off" --subsystem 
    com.apple.CoreTelephony
    
  3. From the Xcode menu open: Product > Scheme > Edit Scheme

    On your Environment Variables set OS_ACTIVITY_MODE = disable

  4. Restart simulator