Face ID error saying "Lost connection to coreauthd."

Number:rdar://34769844 Date Originated:10/2/2017
Status:Closed Resolved:iOS 11.1
Product:Xcode Product Version:9.1 Beta (9B37)
Classification:Developer Tools Reproducible:Always
When using Face ID on Xcode 9.1 Beta simulator, authentication will fail every other time, saying "Lost connection to coreauthd." in the error message.

Steps to Reproduce:
1. Write code to use Face ID (Sample code: https://github.com/jsambuo/TestFaceID)
2. Use the iPhone X Simulator.
3. Attempt to authenticate with Face ID.
4. When prompted, select Hardware > Face ID > Matching Face.
5. Try this about five times.

Expected Results:
Face ID should succeed every time.

Actual Results:
Authentication will fail every other time.
Video: https://youtu.be/4GyaOymoHN0

Xcode 9.1 Beta (9B37)

iPhone X simulator



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