error AD0001: SonarAnalyzer.Rules.CSharp.SymbolicExecutionRunner showed up with SonarAnalyzer.Csharp 9.20.0.85982

[jaz2038]

Description

Upgraded SonarAnalyzer.CSharp from 9.19.0.84025 to 9.20.0.85982 and started hitting this error with multiple builds:

CSC : error AD0001: Analyzer 'SonarAnalyzer.Rules.CSharp.SymbolicExecutionRunner' threw an exception of type 'SonarAnalyzer.SymbolicExecution.SymbolicExecutionException' with message 'Error processing method: XXX 
 Method file: YYY 
 Method line: 120,4 
 Inner exception: System.NullReferenceException: Object reference not set to an instance of an object. 
    at SonarAnalyzer.SymbolicExecution.Roslyn.BinaryOperatorKindExtensions.NumberConstraintFromRelationalOperator(BinaryOperatorKind kind, NumberConstraint existingNumber, NumberConstraint comparedNumber) 
    at SonarAnalyzer.SymbolicExecution.Roslyn.OperationProcessors.IsPattern.LearnBranchingConstraint(ProgramState state, IPatternOperationWrapper pattern, Boolean falseBranch, Boolean hasObjectConstraint, NumberConstraint numberConstraint) 
    at SonarAnalyzer.SymbolicExecution.Roslyn.OperationProcessors.IsPattern.LearnBranchingConstraint(ProgramState state, IIsPatternOperationWrapper operation, Boolean falseBranch) 
    at SonarAnalyzer.SymbolicExecution.Roslyn.OperationProcessors.BranchingProcessor`1.Process(SymbolicContext context, T operation) 
    at SonarAnalyzer.SymbolicExecution.Roslyn.OperationProcessors.MultiProcessor`1.Process(SymbolicContext context) 
    at SonarAnalyzer.SymbolicExecution.Roslyn.OperationDispatcher.Process(SymbolicContext context) 
    at SonarAnalyzer.SymbolicExecution.Roslyn.RoslynSymbolicExecution.ProcessOperation(ExplodedNode node)+MoveNext() 
    at SonarAnalyzer.SymbolicExecution.Roslyn.RoslynSymbolicExecution.Execute() 
    at SonarAnalyzer.Rules.SymbolicExecutionRunnerBase.AnalyzeRoslyn(SonarAnalysisContext analysisContext, SonarSyntaxNodeReportingContext nodeContext, ISymbol symbol)'. 

Repro steps

This error occurred in several areas of code, looks like typically happens with a switch:
private static double GetNormalizedNumMonthsForPastDate(double numMonths) { var normalizedNumMonths = numMonths switch { < 0 => Constants.MinMonthsValue, >= Constants.MaxMonthsValue => Constants.MinMonthsValue, _ => 12 - numMonths }; normalizedNumMonths += 1; return normalizedNumMonths; }

Known workarounds

Related information

• C# 12.0
• Jetbrains Rider 2023.3.3
• .net 8.0.2
• MacOS

[jaz2038]

@zsolt-kolbay-sonarsource looks like potential regression introduced in this PR: #8686

[zsolt-kolbay-sonarsource]

Thank you for reporting the issue. We will treat it with high priority.