Crash in lldb-rpc-server

Number:rdar://49489882 Date Originated:4/1/2019
Status:Open Resolved:DUPLICATE OF 47348115
Product:Xcode Product Version:20.1
Classification:Crash Reproducible:always
Summary: lldp-rpc-server crashes which results in Xcode displaying a message 'Could not attach to pid : "pid"'

Steps to Reproduce:

Create a new single-view iOS application.
Select a simulator and select Product->Run.

Expected Results: The app should launch in the simulator and lldb should connect to it.

Actual Results: The app does launch in the simulator but lldb can't connect to it because it has crashed (and left a crash log in ~/Library/Logs/DiagnosticReports/).

It seems that I can work around the issue (i.e., the rpc server won't crash) if I enable the Address Sanitizer or the Thread Sanitizer before running. 

Version/Build: Xcode 10.2


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