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src/Compilers/Core/Portable/DiagnosticAnalyzer/AnalysisState.cs

@@ -480,6 +480,7 @@ public async Task OnCompilationEventProcessedAsync(CompilationEvent compilationE
             }
 
             // Remove the event from event map.
+            // Note: We do not pass in the cancellationToken to DisposableWait to ensure the state is updated.
             using (_gate.DisposableWait())
             {
                 UpdateEventsMap_NoLock(compilationEvent, add: false);