Beginning on 5/25, a stage of the WinUI build which executes on hosted VS2019 agents, began failing intermittently with the stack below. Subsequent runs of the pipeline produce different combinations of success/failure.
MSBUILD : error MSB4017: The build stopped unexpectedly because of an unexpected logger failure.
Microsoft.Build.Exceptions.InternalLoggerException: The build stopped unexpectedly because of an unexpected logger failure. ---> System.NullReferenceException: Object reference not set to an instance of an object.
at MSBuild.Logger.BuildConfiguration.Equals(Object obj)
at System.Collections.Generic.ObjectEqualityComparer`1.Equals(T x, T y)
at System.Collections.Generic.List`1.Contains(T item)
at MSBuild.Logger.ProjectTrees.AddTopLevelProject(ProjectStartedEventArgs startedEvent, BuildConfiguration platformConfiguration)
at MSBuild.Logger.CentralLogger.HandleProjectStarted(Object sender, ProjectStartedEventArgs e)
at Microsoft.Build.BackEnd.Logging.EventSourceSink.RaiseProjectStartedEvent(Object sender, ProjectStartedEventArgs buildEvent)
Beginning on 5/25, a stage of the WinUI build which executes on hosted VS2019 agents, began failing intermittently with the stack below. Subsequent runs of the pipeline produce different combinations of success/failure.