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src/Workspaces/Core/MSBuild.BuildHost/Build/ProjectBuildManager.cs

@@ -167,6 +167,8 @@ public void StartBatchBuild(IDictionary<string, string>? globalProperties = null
                 Verbosity = MSB.Framework.LoggerVerbosity.Normal
             };
 
+            // We already separately collect the DiagnosticLog in evaluation, so we don't need
+            // to pass the _batchBuildLogger here, we just need the binlog in the ProjectCollection.
             var loggers = _msbuildLogger is not null
                 ? ImmutableArray.Create(_msbuildLogger)
                 : ImmutableArray<MSB.Framework.ILogger>.Empty;
@@ -175,6 +177,8 @@ public void StartBatchBuild(IDictionary<string, string>? globalProperties = null
 
             var buildParameters = new MSB.Execution.BuildParameters(_batchBuildProjectCollection)
             {
+                // The loggers are not inherited from the project collection, so specify the
+                // binlog logger and the _batchBuildLogger (to collect the DiagnosticLog for build) here.
                 Loggers = loggers.Add(_batchBuildLogger),
                 // If we have an additional logger and it's diagnostic, then we need to opt into task inputs globally, or otherwise
                 // it won't get any log events. This logic matches https://github.com/dotnet/msbuild/blob/fa6710d2720dcf1230a732a8858ffe71bcdbe110/src/Build/Instance/ProjectInstance.cs#L2365-L2371