Roslyn: `"csc.exe" exited with code -2146232797.` using Version 5.0.100-preview.8.20417.9

[Unknown6656]

Version Used:

• MS Build Engine 16.8.0-preview-20414-02+a55ce4fbb
• .NET Core SDK 5.0.100-preview.8.20417.9

Steps to Reproduce:
This may be reproducable by cloning https://github.com/Unknown6656/Unknown6656.Core and trying to build the project /Unknown6656.Core/Unknown6656.Core.csproj using the .NET Core SDK version 5.0.100-preview.8.20417.9

Expected Behavior:
No crash of csc.exe (at least, it did not crash on version 5.0.100-preview.7.20366.6)

Actual Behavior:
(I'm so sorry for the wall of text)

Microsoft (R) Build Engine version 16.8.0-preview-20414-02+a55ce4fbb for .NET
Copyright (C) Microsoft Corporation. All rights reserved.

  Determining projects to restore...
  All projects are up-to-date for restore.
  You are using a preview version of .NET. See: https://aka.ms/dotnet-core-preview
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error : Process terminated. System.InvalidOperationException: This program location is thought to be unreachable. [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.PatternExplainer.ShortestPathToNode(ImmutableArray`1 nodes, BoundDecisionDagNode node, Boolean nullPaths, Boolean& requiresFalseWhenClause) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.PatternExplainer.SamplePatternForPathToDagNode(BoundDagTemp rootIdentifier, ImmutableArray`1 nodes, BoundDecisionDagNode targetNode, Boolean nullPaths, Boolean& requiresFalseWhenClause) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.CheckSwitchExpressionExhaustive(SwitchExpressionSyntax node, BoundExpression boundInputExpression, ImmutableArray`1 switchArms, BoundDecisionDag& decisionDag, LabelSymbol& defaultLabel, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.BindSwitchExpressionCore(SwitchExpressionSyntax node, Binder originalBinder, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindExpressionInternal(ExpressionSyntax node, DiagnosticBag diagnostics, Boolean invoked, Boolean indexed) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindExpression(ExpressionSyntax node, DiagnosticBag diagnostics, Boolean invoked, Boolean indexed) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleArrayInitializer(ExpressionSyntax node, TypeSymbol destinationType, BindValueKind valueKind, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindVariableDeclaration(SourceLocalSymbol localSymbol, LocalDeclarationKind kind, Boolean isVar, VariableDeclaratorSyntax declarator, TypeSyntax typeSyntax, TypeWithAnnotations declTypeOpt, AliasSymbol aliasOpt, DiagnosticBag diagnostics, Boolean includeBoundType, CSharpSyntaxNode associatedSyntaxNode) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindDeclarationStatementParts(LocalDeclarationStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindLocalDeclarationStatement(LocalDeclarationStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleEmbeddedStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindIfStatement(IfStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(CSharpSyntaxNode declaration, BlockSyntax blockBody, ArrowExpressionClauseSyntax expressionBody, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(CSharpSyntaxNode syntax, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.BindMethodBody(MethodSymbol method, TypeCompilationState compilationState, DiagnosticBag diagnostics, ImportChain& importChain, Boolean& originalBodyNested, InitialState& forSemanticModel) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileMethod(MethodSymbol methodSymbol, Int32 methodOrdinal, ProcessedFieldInitializers& processedInitializers, SynthesizedSubmissionFields previousSubmissionFields, TypeCompilationState compilationState) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileNamedType(NamedTypeSymbol containingType) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.<>c__DisplayClass22_0.<CompileNamedTypeAsync>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Environment.FailFast(System.String, System.Exception) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.FailFast.OnFatalException(System.Exception) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.FatalError.Report(System.Exception, System.Action`1<System.Exception>) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.FatalError.ReportUnlessCanceled(System.Exception) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler+<>c__DisplayClass22_0.<CompileNamedTypeAsync>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.PatternExplainer.ShortestPathToNode(System.Collections.Immutable.ImmutableArray`1<Microsoft.CodeAnalysis.CSharp.BoundDecisionDagNode>, Microsoft.CodeAnalysis.CSharp.BoundDecisionDagNode, Boolean, Boolean ByRef) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.PatternExplainer.SamplePatternForPathToDagNode(Microsoft.CodeAnalysis.CSharp.BoundDagTemp, System.Collections.Immutable.ImmutableArray`1<Microsoft.CodeAnalysis.CSharp.BoundDecisionDagNode>, Microsoft.CodeAnalysis.CSharp.BoundDecisionDagNode, Boolean, Boolean ByRef) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.CheckSwitchExpressionExhaustive(Microsoft.CodeAnalysis.CSharp.Syntax.SwitchExpressionSyntax, Microsoft.CodeAnalysis.CSharp.BoundExpression, System.Collections.Immutable.ImmutableArray`1<Microsoft.CodeAnalysis.CSharp.BoundSwitchExpressionArm>, Microsoft.CodeAnalysis.CSharp.BoundDecisionDag ByRef, Microsoft.CodeAnalysis.CSharp.Symbols.LabelSymbol ByRef, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.BindSwitchExpressionCore(Microsoft.CodeAnalysis.CSharp.Syntax.SwitchExpressionSyntax, Microsoft.CodeAnalysis.CSharp.Binder, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindExpressionInternal(Microsoft.CodeAnalysis.CSharp.Syntax.ExpressionSyntax, Microsoft.CodeAnalysis.DiagnosticBag, Boolean, Boolean) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindExpression(Microsoft.CodeAnalysis.CSharp.Syntax.ExpressionSyntax, Microsoft.CodeAnalysis.DiagnosticBag, Boolean, Boolean) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleArrayInitializer(Microsoft.CodeAnalysis.CSharp.Syntax.ExpressionSyntax, Microsoft.CodeAnalysis.CSharp.Symbols.TypeSymbol, BindValueKind, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindVariableDeclaration(Microsoft.CodeAnalysis.CSharp.Symbols.SourceLocalSymbol, Microsoft.CodeAnalysis.CSharp.Symbols.LocalDeclarationKind, Boolean, Microsoft.CodeAnalysis.CSharp.Syntax.VariableDeclaratorSyntax, Microsoft.CodeAnalysis.CSharp.Syntax.TypeSyntax, Microsoft.CodeAnalysis.CSharp.Symbols.TypeWithAnnotations, Microsoft.CodeAnalysis.CSharp.Symbols.AliasSymbol, Microsoft.CodeAnalysis.DiagnosticBag, Boolean, Microsoft.CodeAnalysis.CSharp.CSharpSyntaxNode) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindDeclarationStatementParts(Microsoft.CodeAnalysis.CSharp.Syntax.LocalDeclarationStatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindLocalDeclarationStatement(Microsoft.CodeAnalysis.CSharp.Syntax.LocalDeclarationStatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleEmbeddedStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindIfStatement(Microsoft.CodeAnalysis.CSharp.Syntax.IfStatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(Microsoft.CodeAnalysis.CSharp.CSharpSyntaxNode, Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.CSharp.Syntax.ArrowExpressionClauseSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(Microsoft.CodeAnalysis.CSharp.CSharpSyntaxNode, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.BindMethodBody(Microsoft.CodeAnalysis.CSharp.Symbols.MethodSymbol, Microsoft.CodeAnalysis.CSharp.TypeCompilationState, Microsoft.CodeAnalysis.DiagnosticBag, Microsoft.CodeAnalysis.CSharp.ImportChain ByRef, Boolean ByRef, InitialState ByRef) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileMethod(Microsoft.CodeAnalysis.CSharp.Symbols.MethodSymbol, Int32, ProcessedFieldInitializers ByRef, Microsoft.CodeAnalysis.CSharp.SynthesizedSubmissionFields, Microsoft.CodeAnalysis.CSharp.TypeCompilationState) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileNamedType(Microsoft.CodeAnalysis.CSharp.Symbols.NamedTypeSymbol) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler+<>c__DisplayClass22_0.<CompileNamedTypeAsync>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Roslyn.Utilities.UICultureUtilities+<>c__DisplayClass5_0.<WithCurrentUICulture>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Threading.Tasks.Task.InnerInvoke() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Threading.Tasks.Task+<>c.<.cctor>b__277_0(System.Object) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(System.Threading.Thread, System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Threading.Tasks.Task.ExecuteWithThreadLocal(System.Threading.Tasks.Task ByRef, System.Threading.Thread) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Threading.Tasks.Task.ExecuteEntryUnsafe(System.Threading.Thread) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Threading.Tasks.Task.ExecuteFromThreadPool(System.Threading.Thread) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Threading.ThreadPoolWorkQueue.Dispatch() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error : System.InvalidOperationException: This program location is thought to be unreachable. [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.PatternExplainer.ShortestPathToNode(ImmutableArray`1 nodes, BoundDecisionDagNode node, Boolean nullPaths, Boolean& requiresFalseWhenClause) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.PatternExplainer.SamplePatternForPathToDagNode(BoundDagTemp rootIdentifier, ImmutableArray`1 nodes, BoundDecisionDagNode targetNode, Boolean nullPaths, Boolean& requiresFalseWhenClause) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.CheckSwitchExpressionExhaustive(SwitchExpressionSyntax node, BoundExpression boundInputExpression, ImmutableArray`1 switchArms, BoundDecisionDag& decisionDag, LabelSymbol& defaultLabel, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.BindSwitchExpressionCore(SwitchExpressionSyntax node, Binder originalBinder, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindExpressionInternal(ExpressionSyntax node, DiagnosticBag diagnostics, Boolean invoked, Boolean indexed) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindExpression(ExpressionSyntax node, DiagnosticBag diagnostics, Boolean invoked, Boolean indexed) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleArrayInitializer(ExpressionSyntax node, TypeSymbol destinationType, BindValueKind valueKind, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindVariableDeclaration(SourceLocalSymbol localSymbol, LocalDeclarationKind kind, Boolean isVar, VariableDeclaratorSyntax declarator, TypeSyntax typeSyntax, TypeWithAnnotations declTypeOpt, AliasSymbol aliasOpt, DiagnosticBag diagnostics, Boolean includeBoundType, CSharpSyntaxNode associatedSyntaxNode) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindDeclarationStatementParts(LocalDeclarationStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindLocalDeclarationStatement(LocalDeclarationStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleEmbeddedStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindIfStatement(IfStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(CSharpSyntaxNode declaration, BlockSyntax blockBody, ArrowExpressionClauseSyntax expressionBody, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(CSharpSyntaxNode syntax, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.BindMethodBody(MethodSymbol method, TypeCompilationState compilationState, DiagnosticBag diagnostics, ImportChain& importChain, Boolean& originalBodyNested, InitialState& forSemanticModel) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileMethod(MethodSymbol methodSymbol, Int32 methodOrdinal, ProcessedFieldInitializers& processedInitializers, SynthesizedSubmissionFields previousSubmissionFields, TypeCompilationState compilationState) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileNamedType(NamedTypeSymbol containingType) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.<>c__DisplayClass22_0.<CompileNamedTypeAsync>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]

Build FAILED.

C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error : Process terminated. System.InvalidOperationException: This program location is thought to be unreachable. [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.PatternExplainer.ShortestPathToNode(ImmutableArray`1 nodes, BoundDecisionDagNode node, Boolean nullPaths, Boolean& requiresFalseWhenClause) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.PatternExplainer.SamplePatternForPathToDagNode(BoundDagTemp rootIdentifier, ImmutableArray`1 nodes, BoundDecisionDagNode targetNode, Boolean nullPaths, Boolean& requiresFalseWhenClause) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.CheckSwitchExpressionExhaustive(SwitchExpressionSyntax node, BoundExpression boundInputExpression, ImmutableArray`1 switchArms, BoundDecisionDag& decisionDag, LabelSymbol& defaultLabel, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.BindSwitchExpressionCore(SwitchExpressionSyntax node, Binder originalBinder, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindExpressionInternal(ExpressionSyntax node, DiagnosticBag diagnostics, Boolean invoked, Boolean indexed) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindExpression(ExpressionSyntax node, DiagnosticBag diagnostics, Boolean invoked, Boolean indexed) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleArrayInitializer(ExpressionSyntax node, TypeSymbol destinationType, BindValueKind valueKind, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindVariableDeclaration(SourceLocalSymbol localSymbol, LocalDeclarationKind kind, Boolean isVar, VariableDeclaratorSyntax declarator, TypeSyntax typeSyntax, TypeWithAnnotations declTypeOpt, AliasSymbol aliasOpt, DiagnosticBag diagnostics, Boolean includeBoundType, CSharpSyntaxNode associatedSyntaxNode) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindDeclarationStatementParts(LocalDeclarationStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindLocalDeclarationStatement(LocalDeclarationStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleEmbeddedStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindIfStatement(IfStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(CSharpSyntaxNode declaration, BlockSyntax blockBody, ArrowExpressionClauseSyntax expressionBody, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(CSharpSyntaxNode syntax, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.BindMethodBody(MethodSymbol method, TypeCompilationState compilationState, DiagnosticBag diagnostics, ImportChain& importChain, Boolean& originalBodyNested, InitialState& forSemanticModel) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileMethod(MethodSymbol methodSymbol, Int32 methodOrdinal, ProcessedFieldInitializers& processedInitializers, SynthesizedSubmissionFields previousSubmissionFields, TypeCompilationState compilationState) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileNamedType(NamedTypeSymbol containingType) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.<>c__DisplayClass22_0.<CompileNamedTypeAsync>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Environment.FailFast(System.String, System.Exception) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.FailFast.OnFatalException(System.Exception) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.FatalError.Report(System.Exception, System.Action`1<System.Exception>) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.FatalError.ReportUnlessCanceled(System.Exception) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler+<>c__DisplayClass22_0.<CompileNamedTypeAsync>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.PatternExplainer.ShortestPathToNode(System.Collections.Immutable.ImmutableArray`1<Microsoft.CodeAnalysis.CSharp.BoundDecisionDagNode>, Microsoft.CodeAnalysis.CSharp.BoundDecisionDagNode, Boolean, Boolean ByRef) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.PatternExplainer.SamplePatternForPathToDagNode(Microsoft.CodeAnalysis.CSharp.BoundDagTemp, System.Collections.Immutable.ImmutableArray`1<Microsoft.CodeAnalysis.CSharp.BoundDecisionDagNode>, Microsoft.CodeAnalysis.CSharp.BoundDecisionDagNode, Boolean, Boolean ByRef) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.CheckSwitchExpressionExhaustive(Microsoft.CodeAnalysis.CSharp.Syntax.SwitchExpressionSyntax, Microsoft.CodeAnalysis.CSharp.BoundExpression, System.Collections.Immutable.ImmutableArray`1<Microsoft.CodeAnalysis.CSharp.BoundSwitchExpressionArm>, Microsoft.CodeAnalysis.CSharp.BoundDecisionDag ByRef, Microsoft.CodeAnalysis.CSharp.Symbols.LabelSymbol ByRef, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.BindSwitchExpressionCore(Microsoft.CodeAnalysis.CSharp.Syntax.SwitchExpressionSyntax, Microsoft.CodeAnalysis.CSharp.Binder, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindExpressionInternal(Microsoft.CodeAnalysis.CSharp.Syntax.ExpressionSyntax, Microsoft.CodeAnalysis.DiagnosticBag, Boolean, Boolean) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindExpression(Microsoft.CodeAnalysis.CSharp.Syntax.ExpressionSyntax, Microsoft.CodeAnalysis.DiagnosticBag, Boolean, Boolean) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleArrayInitializer(Microsoft.CodeAnalysis.CSharp.Syntax.ExpressionSyntax, Microsoft.CodeAnalysis.CSharp.Symbols.TypeSymbol, BindValueKind, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindVariableDeclaration(Microsoft.CodeAnalysis.CSharp.Symbols.SourceLocalSymbol, Microsoft.CodeAnalysis.CSharp.Symbols.LocalDeclarationKind, Boolean, Microsoft.CodeAnalysis.CSharp.Syntax.VariableDeclaratorSyntax, Microsoft.CodeAnalysis.CSharp.Syntax.TypeSyntax, Microsoft.CodeAnalysis.CSharp.Symbols.TypeWithAnnotations, Microsoft.CodeAnalysis.CSharp.Symbols.AliasSymbol, Microsoft.CodeAnalysis.DiagnosticBag, Boolean, Microsoft.CodeAnalysis.CSharp.CSharpSyntaxNode) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindDeclarationStatementParts(Microsoft.CodeAnalysis.CSharp.Syntax.LocalDeclarationStatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindLocalDeclarationStatement(Microsoft.CodeAnalysis.CSharp.Syntax.LocalDeclarationStatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleEmbeddedStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindIfStatement(Microsoft.CodeAnalysis.CSharp.Syntax.IfStatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(Microsoft.CodeAnalysis.CSharp.CSharpSyntaxNode, Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.CSharp.Syntax.ArrowExpressionClauseSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(Microsoft.CodeAnalysis.CSharp.CSharpSyntaxNode, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.BindMethodBody(Microsoft.CodeAnalysis.CSharp.Symbols.MethodSymbol, Microsoft.CodeAnalysis.CSharp.TypeCompilationState, Microsoft.CodeAnalysis.DiagnosticBag, Microsoft.CodeAnalysis.CSharp.ImportChain ByRef, Boolean ByRef, InitialState ByRef) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileMethod(Microsoft.CodeAnalysis.CSharp.Symbols.MethodSymbol, Int32, ProcessedFieldInitializers ByRef, Microsoft.CodeAnalysis.CSharp.SynthesizedSubmissionFields, Microsoft.CodeAnalysis.CSharp.TypeCompilationState) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileNamedType(Microsoft.CodeAnalysis.CSharp.Symbols.NamedTypeSymbol) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler+<>c__DisplayClass22_0.<CompileNamedTypeAsync>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Roslyn.Utilities.UICultureUtilities+<>c__DisplayClass5_0.<WithCurrentUICulture>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Threading.Tasks.Task.InnerInvoke() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Threading.Tasks.Task+<>c.<.cctor>b__277_0(System.Object) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(System.Threading.Thread, System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Threading.Tasks.Task.ExecuteWithThreadLocal(System.Threading.Tasks.Task ByRef, System.Threading.Thread) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Threading.Tasks.Task.ExecuteEntryUnsafe(System.Threading.Thread) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Threading.Tasks.Task.ExecuteFromThreadPool(System.Threading.Thread) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Threading.ThreadPoolWorkQueue.Dispatch() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error : System.InvalidOperationException: This program location is thought to be unreachable. [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.PatternExplainer.ShortestPathToNode(ImmutableArray`1 nodes, BoundDecisionDagNode node, Boolean nullPaths, Boolean& requiresFalseWhenClause) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.PatternExplainer.SamplePatternForPathToDagNode(BoundDagTemp rootIdentifier, ImmutableArray`1 nodes, BoundDecisionDagNode targetNode, Boolean nullPaths, Boolean& requiresFalseWhenClause) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.CheckSwitchExpressionExhaustive(SwitchExpressionSyntax node, BoundExpression boundInputExpression, ImmutableArray`1 switchArms, BoundDecisionDag& decisionDag, LabelSymbol& defaultLabel, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.BindSwitchExpressionCore(SwitchExpressionSyntax node, Binder originalBinder, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindExpressionInternal(ExpressionSyntax node, DiagnosticBag diagnostics, Boolean invoked, Boolean indexed) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindExpression(ExpressionSyntax node, DiagnosticBag diagnostics, Boolean invoked, Boolean indexed) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleArrayInitializer(ExpressionSyntax node, TypeSymbol destinationType, BindValueKind valueKind, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindVariableDeclaration(SourceLocalSymbol localSymbol, LocalDeclarationKind kind, Boolean isVar, VariableDeclaratorSyntax declarator, TypeSyntax typeSyntax, TypeWithAnnotations declTypeOpt, AliasSymbol aliasOpt, DiagnosticBag diagnostics, Boolean includeBoundType, CSharpSyntaxNode associatedSyntaxNode) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindDeclarationStatementParts(LocalDeclarationStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindLocalDeclarationStatement(LocalDeclarationStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleEmbeddedStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindIfStatement(IfStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(CSharpSyntaxNode declaration, BlockSyntax blockBody, ArrowExpressionClauseSyntax expressionBody, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(CSharpSyntaxNode syntax, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.BindMethodBody(MethodSymbol method, TypeCompilationState compilationState, DiagnosticBag diagnostics, ImportChain& importChain, Boolean& originalBodyNested, InitialState& forSemanticModel) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileMethod(MethodSymbol methodSymbol, Int32 methodOrdinal, ProcessedFieldInitializers& processedInitializers, SynthesizedSubmissionFields previousSubmissionFields, TypeCompilationState compilationState) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileNamedType(NamedTypeSymbol containingType) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
C:\Program Files\dotnet\sdk\5.0.100-preview.8.20417.9\Roslyn\Microsoft.CSharp.Core.targets(70,5): error :    at Microsoft.CodeAnalysis.CSharp.MethodCompiler.<>c__DisplayClass22_0.<CompileNamedTypeAsync>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]

[vladshestel]

Had the same issue with SDK 5.0.100-preview.8.20417.9.

Seems like C# 8 switch pattern-matching with property pattern and when clause leads to the compilation error.
I have an example program which compiles with 5.0.100-preview.7.20366.6 sdk version and fails with preview 8.

using System;

namespace preview_8_console
{
    public class Animal { }
    public class Cat : Animal { }
    public class Dog : Animal
    {
        public bool IsFunny { get; set; }
        public int? JokesCount { get; set; }
    }

    public class Program
    {
        public static void Main(string[] args)
        {
                Console.WriteLine(Pattern(new Dog()));
        }

        private static string Pattern(Dog dog)
            => dog switch
            {
                    { IsFunny: false } when dog.JokesCount == null => "this is a regular dog",
                    { IsFunny: false } when dog.JokesCount > 0 => "this is a dog with wierd jokes",
                    { IsFunny: true } => "this is a funny dog"
            };
    }
}

Seems like problem with @gafter changes inside SwitchExpressionBinder.cs.

[Unknown6656]

@vladshestel Thank you for tracking the issue down!
Do you think it might be this line: https://github.com/dotnet/roslyn/blob/06c2acecbc9771e8e0cf96d7cf07aa7d76dc7dac/src/Compilers/CSharp/Portable/Binder/SwitchExpressionBinder.cs#L101...L102 ?

[gafter]

@RikkiGibson @jcouv Here is another crash in recent pattern-matching changes. I suspect this does not affect 16.7.

[Unknown6656]

@gafter It affects Visual Studio Preview 2019 Version 16.7.2 -- that is the version I used to compile the mentioned code with.
..... or does "16.7" refer to a version prior to 16.7.2? If so, then you are correct: it does not affect 16.7.1 and 16.7.0

[RikkiGibson]

It is assumed to mean the latest 16.7 patch release, currently 16.7.2.

It is surprising that 16.7.1 could present a different behavior than 16.7.2 here--we don't believe that any compiler changes related to this area went in between those releases.

[Unknown6656]

In the meantime, is it possible to target an older .NET5 preview without having to re-install Visual Studio to an older version?
I have 5.0.100-preview.8.20417.9 and 5.0.100-preview.7.20366.6 installed.
Can I target the preview7-version specifically using <TargetFramework>...</TargetFramework>? Otherwise, .NET5 becomes pretty much unusable with the current installation of Visual Studio.
_(I cannot uninstall 5.0.100-preview.8.20417.9, as it is bound to the Visual Studio installation)_

[RikkiGibson]

You can override the version of the compiler that gets used for builds by following these instructions: https://github.com/dotnet/roslyn/blob/master/docs/compilers/Compiler%20Toolset%20NuPkgs.md

[Unknown6656]

@RikkiGibson Thanks a lot!!

---

Interestingly enough, I now get a lot of AggregateExceptions inside the Visual Studio IDE. Checking the VS log files reveals the following stack trace:

System.AggregateException: One or more errors occurred. ---> System.Threading.Tasks.TaskCanceledException: A task was canceled.
--- End of inner exception stack trace ---
   at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
   at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
   at Microsoft.CodeAnalysis.Editor.Implementation.Classification.SemanticClassificationBufferTaggerProvider.Tagger.GetAllTags(NormalizedSnapshotSpanCollection spans, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.Text.Tagging.Implementation.TagAggregator`1.<GetTagsForBuffer>d__47.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at Microsoft.VisualStudio.Telemetry.WindowsErrorReporting.WatsonReport.GetClrWatsonExceptionInfo(Exception exceptionObject)
---> (Inner Exception #0) System.Threading.Tasks.TaskCanceledException: A task was canceled.<---

... though I doubt that it is relevant to the current issue at hand.

[Unknown6656]

The issue still exists in 5.0.100-rc.1.20452.10

[jcouv]

@Unknown6656 Yes, that's likely. RC1 predates this fix.

[Unknown6656]

@jcouv: Oh ok, I did not know that. Thanks ^^

[Unknown6656]

You can override the version of the compiler that gets used for builds by following these instructions: https://github.com/dotnet/roslyn/blob/master/docs/compilers/Compiler%20Toolset%20NuPkgs.md

@RikkiGibson I tested it again with the NuGet Release 3.8.0-3.final, and the issue still persists with the same error.

.csproj:

<Project Sdk="Microsoft.NET.Sdk">
    <PropertyGroup>
        <TargetFramework>net5</TargetFramework>
        <LangVersion>latest</LangVersion>
[...]
    </PropertyGroup>
    <ItemGroup>
        <PackageReference Include="Microsoft.Net.Compilers.Toolset" Version="3.8.0-3.final">
          <PrivateAssets>all</PrivateAssets>
          <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
        </PackageReference>
    </ItemGroup>
[...]

Error:

C:\Users\unknown6656\.nuget\packages\microsoft.net.compilers.toolset\3.8.0-3.final\tasks\netcoreapp3.1\Microsoft.CSharp.Core.targets(70,5): error :

Process terminated. System.InvalidOperationException: This program location is thought to be unreachable. [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.PatternExplainer.ShortestPathToNode(ImmutableArray`1 nodes, BoundDecisionDagNode node, Boolean nullPaths, Boolean& requiresFalseWhenClause) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.PatternExplainer.SamplePatternForPathToDagNode(BoundDagTemp rootIdentifier, ImmutableArray`1 nodes, BoundDecisionDagNode targetNode, Boolean nullPaths, Boolean& requiresFalseWhenClause) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.CheckSwitchExpressionExhaustive(SwitchExpressionSyntax node, BoundExpression boundInputExpression, ImmutableArray`1 switchArms, BoundDecisionDag& decisionDag, LabelSymbol& defaultLabel, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.BindSwitchExpressionCore(SwitchExpressionSyntax node, Binder originalBinder, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindSwitchExpression(SwitchExpressionSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindExpressionInternal(ExpressionSyntax node, DiagnosticBag diagnostics, Boolean invoked, Boolean indexed) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindExpression(ExpressionSyntax node, DiagnosticBag diagnostics, Boolean invoked, Boolean indexed) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindValue(ExpressionSyntax node, DiagnosticBag diagnostics, BindValueKind valueKind) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleArrayInitializer(ExpressionSyntax node, TypeSymbol destinationType, BindValueKind valueKind, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindVariableDeclaration(SourceLocalSymbol localSymbol, LocalDeclarationKind kind, Boolean isVar, VariableDeclaratorSyntax declarator, TypeSyntax typeSyntax, TypeWithAnnotations declTypeOpt, AliasSymbol aliasOpt, DiagnosticBag diagnostics, Boolean includeBoundType, CSharpSyntaxNode associatedSyntaxNode) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindDeclarationStatementParts(LocalDeclarationStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindLocalDeclarationStatement(LocalDeclarationStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleEmbeddedStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindIfStatement(IfStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(CSharpSyntaxNode declaration, BlockSyntax blockBody, ArrowExpressionClauseSyntax expressionBody, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(CSharpSyntaxNode syntax, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.BindMethodBody(MethodSymbol method, TypeCompilationState compilationState, DiagnosticBag diagnostics, VariableState nullableInitialState, ImportChain& importChain, Boolean& originalBodyNested, InitialState& forSemanticModel) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileMethod(MethodSymbol methodSymbol, Int32 methodOrdinal, ProcessedFieldInitializers& processedInitializers, SynthesizedSubmissionFields previousSubmissionFields, TypeCompilationState compilationState) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileNamedType(NamedTypeSymbol containingType) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.<>c__DisplayClass22_0.<CompileNamedTypeAsync>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Environment.FailFast(System.String, System.Exception) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.FailFast.OnFatalException(System.Exception) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.FatalError.Report(System.Exception, System.Action`1<System.Exception>) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.FatalError.Report(System.Exception) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.FatalError.ReportUnlessCanceled(System.Exception) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler+<>c__DisplayClass22_0.<CompileNamedTypeAsync>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.PatternExplainer.ShortestPathToNode(System.Collections.Immutable.ImmutableArray`1<Microsoft.CodeAnalysis.CSharp.BoundDecisionDagNode>, Microsoft.CodeAnalysis.CSharp.BoundDecisionDagNode, Boolean, Boolean ByRef) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.PatternExplainer.SamplePatternForPathToDagNode(Microsoft.CodeAnalysis.CSharp.BoundDagTemp, System.Collections.Immutable.ImmutableArray`1<Microsoft.CodeAnalysis.CSharp.BoundDecisionDagNode>, Microsoft.CodeAnalysis.CSharp.BoundDecisionDagNode, Boolean, Boolean ByRef) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.CheckSwitchExpressionExhaustive(Microsoft.CodeAnalysis.CSharp.Syntax.SwitchExpressionSyntax, Microsoft.CodeAnalysis.CSharp.BoundExpression, System.Collections.Immutable.ImmutableArray`1<Microsoft.CodeAnalysis.CSharp.BoundSwitchExpressionArm>, Microsoft.CodeAnalysis.CSharp.BoundDecisionDag ByRef, Microsoft.CodeAnalysis.CSharp.Symbols.LabelSymbol ByRef, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.BindSwitchExpressionCore(Microsoft.CodeAnalysis.CSharp.Syntax.SwitchExpressionSyntax, Microsoft.CodeAnalysis.CSharp.Binder, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindSwitchExpression(Microsoft.CodeAnalysis.CSharp.Syntax.SwitchExpressionSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindExpressionInternal(Microsoft.CodeAnalysis.CSharp.Syntax.ExpressionSyntax, Microsoft.CodeAnalysis.DiagnosticBag, Boolean, Boolean) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindExpression(Microsoft.CodeAnalysis.CSharp.Syntax.ExpressionSyntax, Microsoft.CodeAnalysis.DiagnosticBag, Boolean, Boolean) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindValue(Microsoft.CodeAnalysis.CSharp.Syntax.ExpressionSyntax, Microsoft.CodeAnalysis.DiagnosticBag, BindValueKind) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleArrayInitializer(Microsoft.CodeAnalysis.CSharp.Syntax.ExpressionSyntax, Microsoft.CodeAnalysis.CSharp.Symbols.TypeSymbol, BindValueKind, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindVariableDeclaration(Microsoft.CodeAnalysis.CSharp.Symbols.SourceLocalSymbol, Microsoft.CodeAnalysis.CSharp.Symbols.LocalDeclarationKind, Boolean, Microsoft.CodeAnalysis.CSharp.Syntax.VariableDeclaratorSyntax, Microsoft.CodeAnalysis.CSharp.Syntax.TypeSyntax, Microsoft.CodeAnalysis.CSharp.Symbols.TypeWithAnnotations, Microsoft.CodeAnalysis.CSharp.Symbols.AliasSymbol, Microsoft.CodeAnalysis.DiagnosticBag, Boolean, Microsoft.CodeAnalysis.CSharp.CSharpSyntaxNode) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindDeclarationStatementParts(Microsoft.CodeAnalysis.CSharp.Syntax.LocalDeclarationStatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindLocalDeclarationStatement(Microsoft.CodeAnalysis.CSharp.Syntax.LocalDeclarationStatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleEmbeddedStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindIfStatement(Microsoft.CodeAnalysis.CSharp.Syntax.IfStatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(Microsoft.CodeAnalysis.CSharp.CSharpSyntaxNode, Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.CSharp.Syntax.ArrowExpressionClauseSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(Microsoft.CodeAnalysis.CSharp.CSharpSyntaxNode, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.BindMethodBody(Microsoft.CodeAnalysis.CSharp.Symbols.MethodSymbol, Microsoft.CodeAnalysis.CSharp.TypeCompilationState, Microsoft.CodeAnalysis.DiagnosticBag, VariableState, Microsoft.CodeAnalysis.CSharp.ImportChain ByRef, Boolean ByRef, InitialState ByRef) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileMethod(Microsoft.CodeAnalysis.CSharp.Symbols.MethodSymbol, Int32, ProcessedFieldInitializers ByRef, Microsoft.CodeAnalysis.CSharp.SynthesizedSubmissionFields, Microsoft.CodeAnalysis.CSharp.TypeCompilationState) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileNamedType(Microsoft.CodeAnalysis.CSharp.Symbols.NamedTypeSymbol) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler+<>c__DisplayClass22_0.<CompileNamedTypeAsync>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Roslyn.Utilities.UICultureUtilities+<>c__DisplayClass5_0.<WithCurrentUICulture>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Threading.Tasks.Task.InnerInvoke() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Threading.Tasks.Task+<>c.<.cctor>b__274_0(System.Object) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(System.Threading.Thread, System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Threading.Tasks.Task.ExecuteWithThreadLocal(System.Threading.Tasks.Task ByRef, System.Threading.Thread) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Threading.Tasks.Task.ExecuteEntryUnsafe(System.Threading.Thread) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Threading.Tasks.Task.ExecuteFromThreadPool(System.Threading.Thread) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Threading.ThreadPoolWorkQueue.Dispatch() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
System.InvalidOperationException: This program location is thought to be unreachable. [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.PatternExplainer.ShortestPathToNode(ImmutableArray`1 nodes, BoundDecisionDagNode node, Boolean nullPaths, Boolean& requiresFalseWhenClause) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.PatternExplainer.SamplePatternForPathToDagNode(BoundDagTemp rootIdentifier, ImmutableArray`1 nodes, BoundDecisionDagNode targetNode, Boolean nullPaths, Boolean& requiresFalseWhenClause) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.CheckSwitchExpressionExhaustive(SwitchExpressionSyntax node, BoundExpression boundInputExpression, ImmutableArray`1 switchArms, BoundDecisionDag& decisionDag, LabelSymbol& defaultLabel, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.BindSwitchExpressionCore(SwitchExpressionSyntax node, Binder originalBinder, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindSwitchExpression(SwitchExpressionSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindExpressionInternal(ExpressionSyntax node, DiagnosticBag diagnostics, Boolean invoked, Boolean indexed) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindExpression(ExpressionSyntax node, DiagnosticBag diagnostics, Boolean invoked, Boolean indexed) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindValue(ExpressionSyntax node, DiagnosticBag diagnostics, BindValueKind valueKind) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleArrayInitializer(ExpressionSyntax node, TypeSymbol destinationType, BindValueKind valueKind, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindVariableDeclaration(SourceLocalSymbol localSymbol, LocalDeclarationKind kind, Boolean isVar, VariableDeclaratorSyntax declarator, TypeSyntax typeSyntax, TypeWithAnnotations declTypeOpt, AliasSymbol aliasOpt, DiagnosticBag diagnostics, Boolean includeBoundType, CSharpSyntaxNode associatedSyntaxNode) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindDeclarationStatementParts(LocalDeclarationStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindLocalDeclarationStatement(LocalDeclarationStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleEmbeddedStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindIfStatement(IfStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(CSharpSyntaxNode declaration, BlockSyntax blockBody, ArrowExpressionClauseSyntax expressionBody, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(CSharpSyntaxNode syntax, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.BindMethodBody(MethodSymbol method, TypeCompilationState compilationState, DiagnosticBag diagnostics, VariableState nullableInitialState, ImportChain& importChain, Boolean& originalBodyNested, InitialState& forSemanticModel) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileMethod(MethodSymbol methodSymbol, Int32 methodOrdinal, ProcessedFieldInitializers& processedInitializers, SynthesizedSubmissionFields previousSubmissionFields, TypeCompilationState compilationState) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileNamedType(NamedTypeSymbol containingType) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.<>c__DisplayClass22_0.<CompileNamedTypeAsync>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]

Build FAILED.

Process terminated. System.InvalidOperationException: This program location is thought to be unreachable. [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.PatternExplainer.ShortestPathToNode(ImmutableArray`1 nodes, BoundDecisionDagNode node, Boolean nullPaths, Boolean& requiresFalseWhenClause) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.PatternExplainer.SamplePatternForPathToDagNode(BoundDagTemp rootIdentifier, ImmutableArray`1 nodes, BoundDecisionDagNode targetNode, Boolean nullPaths, Boolean& requiresFalseWhenClause) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.CheckSwitchExpressionExhaustive(SwitchExpressionSyntax node, BoundExpression boundInputExpression, ImmutableArray`1 switchArms, BoundDecisionDag& decisionDag, LabelSymbol& defaultLabel, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.BindSwitchExpressionCore(SwitchExpressionSyntax node, Binder originalBinder, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindSwitchExpression(SwitchExpressionSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindExpressionInternal(ExpressionSyntax node, DiagnosticBag diagnostics, Boolean invoked, Boolean indexed) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindExpression(ExpressionSyntax node, DiagnosticBag diagnostics, Boolean invoked, Boolean indexed) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindValue(ExpressionSyntax node, DiagnosticBag diagnostics, BindValueKind valueKind) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleArrayInitializer(ExpressionSyntax node, TypeSymbol destinationType, BindValueKind valueKind, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindVariableDeclaration(SourceLocalSymbol localSymbol, LocalDeclarationKind kind, Boolean isVar, VariableDeclaratorSyntax declarator, TypeSyntax typeSyntax, TypeWithAnnotations declTypeOpt, AliasSymbol aliasOpt, DiagnosticBag diagnostics, Boolean includeBoundType, CSharpSyntaxNode associatedSyntaxNode) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindDeclarationStatementParts(LocalDeclarationStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindLocalDeclarationStatement(LocalDeclarationStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleEmbeddedStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindIfStatement(IfStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(CSharpSyntaxNode declaration, BlockSyntax blockBody, ArrowExpressionClauseSyntax expressionBody, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(CSharpSyntaxNode syntax, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.BindMethodBody(MethodSymbol method, TypeCompilationState compilationState, DiagnosticBag diagnostics, VariableState nullableInitialState, ImportChain& importChain, Boolean& originalBodyNested, InitialState& forSemanticModel) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileMethod(MethodSymbol methodSymbol, Int32 methodOrdinal, ProcessedFieldInitializers& processedInitializers, SynthesizedSubmissionFields previousSubmissionFields, TypeCompilationState compilationState) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileNamedType(NamedTypeSymbol containingType) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.<>c__DisplayClass22_0.<CompileNamedTypeAsync>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Environment.FailFast(System.String, System.Exception) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.FailFast.OnFatalException(System.Exception) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.FatalError.Report(System.Exception, System.Action`1<System.Exception>) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.FatalError.Report(System.Exception) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.FatalError.ReportUnlessCanceled(System.Exception) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler+<>c__DisplayClass22_0.<CompileNamedTypeAsync>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.PatternExplainer.ShortestPathToNode(System.Collections.Immutable.ImmutableArray`1<Microsoft.CodeAnalysis.CSharp.BoundDecisionDagNode>, Microsoft.CodeAnalysis.CSharp.BoundDecisionDagNode, Boolean, Boolean ByRef) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.PatternExplainer.SamplePatternForPathToDagNode(Microsoft.CodeAnalysis.CSharp.BoundDagTemp, System.Collections.Immutable.ImmutableArray`1<Microsoft.CodeAnalysis.CSharp.BoundDecisionDagNode>, Microsoft.CodeAnalysis.CSharp.BoundDecisionDagNode, Boolean, Boolean ByRef) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.CheckSwitchExpressionExhaustive(Microsoft.CodeAnalysis.CSharp.Syntax.SwitchExpressionSyntax, Microsoft.CodeAnalysis.CSharp.BoundExpression, System.Collections.Immutable.ImmutableArray`1<Microsoft.CodeAnalysis.CSharp.BoundSwitchExpressionArm>, Microsoft.CodeAnalysis.CSharp.BoundDecisionDag ByRef, Microsoft.CodeAnalysis.CSharp.Symbols.LabelSymbol ByRef, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.BindSwitchExpressionCore(Microsoft.CodeAnalysis.CSharp.Syntax.SwitchExpressionSyntax, Microsoft.CodeAnalysis.CSharp.Binder, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindSwitchExpression(Microsoft.CodeAnalysis.CSharp.Syntax.SwitchExpressionSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindExpressionInternal(Microsoft.CodeAnalysis.CSharp.Syntax.ExpressionSyntax, Microsoft.CodeAnalysis.DiagnosticBag, Boolean, Boolean) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindExpression(Microsoft.CodeAnalysis.CSharp.Syntax.ExpressionSyntax, Microsoft.CodeAnalysis.DiagnosticBag, Boolean, Boolean) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindValue(Microsoft.CodeAnalysis.CSharp.Syntax.ExpressionSyntax, Microsoft.CodeAnalysis.DiagnosticBag, BindValueKind) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleArrayInitializer(Microsoft.CodeAnalysis.CSharp.Syntax.ExpressionSyntax, Microsoft.CodeAnalysis.CSharp.Symbols.TypeSymbol, BindValueKind, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindVariableDeclaration(Microsoft.CodeAnalysis.CSharp.Symbols.SourceLocalSymbol, Microsoft.CodeAnalysis.CSharp.Symbols.LocalDeclarationKind, Boolean, Microsoft.CodeAnalysis.CSharp.Syntax.VariableDeclaratorSyntax, Microsoft.CodeAnalysis.CSharp.Syntax.TypeSyntax, Microsoft.CodeAnalysis.CSharp.Symbols.TypeWithAnnotations, Microsoft.CodeAnalysis.CSharp.Symbols.AliasSymbol, Microsoft.CodeAnalysis.DiagnosticBag, Boolean, Microsoft.CodeAnalysis.CSharp.CSharpSyntaxNode) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindDeclarationStatementParts(Microsoft.CodeAnalysis.CSharp.Syntax.LocalDeclarationStatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindLocalDeclarationStatement(Microsoft.CodeAnalysis.CSharp.Syntax.LocalDeclarationStatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleEmbeddedStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindIfStatement(Microsoft.CodeAnalysis.CSharp.Syntax.IfStatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(Microsoft.CodeAnalysis.CSharp.Syntax.StatementSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(Microsoft.CodeAnalysis.CSharp.CSharpSyntaxNode, Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax, Microsoft.CodeAnalysis.CSharp.Syntax.ArrowExpressionClauseSyntax, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(Microsoft.CodeAnalysis.CSharp.CSharpSyntaxNode, Microsoft.CodeAnalysis.DiagnosticBag) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.BindMethodBody(Microsoft.CodeAnalysis.CSharp.Symbols.MethodSymbol, Microsoft.CodeAnalysis.CSharp.TypeCompilationState, Microsoft.CodeAnalysis.DiagnosticBag, VariableState, Microsoft.CodeAnalysis.CSharp.ImportChain ByRef, Boolean ByRef, InitialState ByRef) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileMethod(Microsoft.CodeAnalysis.CSharp.Symbols.MethodSymbol, Int32, ProcessedFieldInitializers ByRef, Microsoft.CodeAnalysis.CSharp.SynthesizedSubmissionFields, Microsoft.CodeAnalysis.CSharp.TypeCompilationState) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileNamedType(Microsoft.CodeAnalysis.CSharp.Symbols.NamedTypeSymbol) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler+<>c__DisplayClass22_0.<CompileNamedTypeAsync>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Roslyn.Utilities.UICultureUtilities+<>c__DisplayClass5_0.<WithCurrentUICulture>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Threading.Tasks.Task.InnerInvoke() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Threading.Tasks.Task+<>c.<.cctor>b__274_0(System.Object) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(System.Threading.Thread, System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Threading.Tasks.Task.ExecuteWithThreadLocal(System.Threading.Tasks.Task ByRef, System.Threading.Thread) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Threading.Tasks.Task.ExecuteEntryUnsafe(System.Threading.Thread) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Threading.Tasks.Task.ExecuteFromThreadPool(System.Threading.Thread) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Threading.ThreadPoolWorkQueue.Dispatch() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
System.InvalidOperationException: This program location is thought to be unreachable. [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.PatternExplainer.ShortestPathToNode(ImmutableArray`1 nodes, BoundDecisionDagNode node, Boolean nullPaths, Boolean& requiresFalseWhenClause) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.PatternExplainer.SamplePatternForPathToDagNode(BoundDagTemp rootIdentifier, ImmutableArray`1 nodes, BoundDecisionDagNode targetNode, Boolean nullPaths, Boolean& requiresFalseWhenClause) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.CheckSwitchExpressionExhaustive(SwitchExpressionSyntax node, BoundExpression boundInputExpression, ImmutableArray`1 switchArms, BoundDecisionDag& decisionDag, LabelSymbol& defaultLabel, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.SwitchExpressionBinder.BindSwitchExpressionCore(SwitchExpressionSyntax node, Binder originalBinder, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindSwitchExpression(SwitchExpressionSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindExpressionInternal(ExpressionSyntax node, DiagnosticBag diagnostics, Boolean invoked, Boolean indexed) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindExpression(ExpressionSyntax node, DiagnosticBag diagnostics, Boolean invoked, Boolean indexed) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindValue(ExpressionSyntax node, DiagnosticBag diagnostics, BindValueKind valueKind) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleArrayInitializer(ExpressionSyntax node, TypeSymbol destinationType, BindValueKind valueKind, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindVariableDeclaration(SourceLocalSymbol localSymbol, LocalDeclarationKind kind, Boolean isVar, VariableDeclaratorSyntax declarator, TypeSyntax typeSyntax, TypeWithAnnotations declTypeOpt, AliasSymbol aliasOpt, DiagnosticBag diagnostics, Boolean includeBoundType, CSharpSyntaxNode associatedSyntaxNode) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindDeclarationStatementParts(LocalDeclarationStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindLocalDeclarationStatement(LocalDeclarationStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindPossibleEmbeddedStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindIfStatement(IfStatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlockParts(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindBlock(BlockSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindStatement(StatementSyntax node, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(CSharpSyntaxNode declaration, BlockSyntax blockBody, ArrowExpressionClauseSyntax expressionBody, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.Binder.BindMethodBody(CSharpSyntaxNode syntax, DiagnosticBag diagnostics) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.BindMethodBody(MethodSymbol method, TypeCompilationState compilationState, DiagnosticBag diagnostics, VariableState nullableInitialState, ImportChain& importChain, Boolean& originalBodyNested, InitialState& forSemanticModel) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileMethod(MethodSymbol methodSymbol, Int32 methodOrdinal, ProcessedFieldInitializers& processedInitializers, SynthesizedSubmissionFields previousSubmissionFields, TypeCompilationState compilationState) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileNamedType(NamedTypeSymbol containingType) [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]
   at Microsoft.CodeAnalysis.CSharp.MethodCompiler.<>c__DisplayClass22_0.<CompileNamedTypeAsync>b__0() [L:\Projects.VisualStudio\Unknown6656.Core\Unknown6656.Core\Unknown6656.Core.csproj]

[RikkiGibson]

Try using a nightly preview4 build such as https://dev.azure.com/dnceng/public/_packaging?_a=package&feed=dotnet-tools&package=Microsoft.Net.Compilers.Toolset&protocolType=NuGet&version=3.8.0-4.20472.6&view=overview

[Unknown6656]

@RikkiGibson : THanks a lot! You just saved my day!
It now works flawlessly