System.InvalidOperationException from LocalRewriter.TransformCompoundAssignmentLHS

[TessenR]

Version Used:

Branch C# 8.0: Nullable reference type (29 Oct 2018)
https://github.com/dotnet/csharplang/blob/master/proposals/nullable-reference-types.md
Latest commit 2f8fef by AlekseyTs:
Compare Nullable modifiers while comparing type symbols by default. (#30770)

Steps to Reproduce:

Compile the following code

class C
{
    void M()
    {
        for (var x = 0; ; x!++) { }
    }
}

https://sharplab.io/#v2:EYLgZgpghgLgrgJwgZwLQDk4BstWFiAJQkiQDsBjCAFQE8AHFAHwAEAmAAgGEBYAKADe/DiI4sALBwCyACgCUw0UL6jVHMAHsEHGQDco2gB4cAvBwAMAbg7XDAQgDUDuRwEcAvopGe+7oA==

Actual Behavior:

System.InvalidOperationException: Unexpected value 'SuppressNullableWarningExpression' of type 'Microsoft.CodeAnalysis.CSharp.BoundKind' at Microsoft.CodeAnalysis.CSharp.LocalRewriter.TransformCompoundAssignmentLHS(BoundExpression originalLHS, ArrayBuilder`1 stores, ArrayBuilder`1 temps, Boolean isDynamicAssignment) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Lowering\LocalRewriter\LocalRewriter_CompoundAssignmentOperator.cs:line 619 at Microsoft.CodeAnalysis.CSharp.LocalRewriter.VisitIncrementOperator(BoundIncrementOperator node) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Lowering\LocalRewriter\LocalRewriter_UnaryOperator.cs:line 418 at Microsoft.CodeAnalysis.CSharp.BoundIncrementOperator.Accept(BoundTreeVisitor visitor) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Generated\BoundNodes.xml.Generated.cs:line 873 at Microsoft.CodeAnalysis.CSharp.BoundTreeRewriterWithStackGuard.VisitExpressionWithoutStackGuard(BoundExpression node) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\BoundTree\BoundTreeRewriter.cs:line 97 at Microsoft.CodeAnalysis.CSharp.BoundTreeVisitor.VisitExpressionWithStackGuard(BoundExpression node) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\BoundTree\BoundTreeVisitors.cs:line 225 at Microsoft.CodeAnalysis.CSharp.BoundTreeVisitor.VisitExpressionWithStackGuard(Int32& recursionDepth, BoundExpression node) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\BoundTree\BoundTreeVisitors.cs:line 206 at Microsoft.CodeAnalysis.CSharp.LocalRewriter.VisitExpressionImpl(BoundExpression node) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Lowering\LocalRewriter\LocalRewriter.cs:line 201 at Microsoft.CodeAnalysis.CSharp.LocalRewriter.VisitUnusedExpression(BoundExpression expression) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Lowering\LocalRewriter\LocalRewriter_ExpressionStatement.cs:line 73 at Microsoft.CodeAnalysis.CSharp.LocalRewriter.RewriteExpressionStatement(BoundExpressionStatement node, Boolean suppressInstrumentation) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Lowering\LocalRewriter\LocalRewriter_ExpressionStatement.cs:line 21 at Microsoft.CodeAnalysis.CSharp.LocalRewriter.VisitExpressionStatement(BoundExpressionStatement node) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Lowering\LocalRewriter\LocalRewriter_ExpressionStatement.cs:line 16 at Microsoft.CodeAnalysis.CSharp.BoundExpressionStatement.Accept(BoundTreeVisitor visitor) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Generated\BoundNodes.xml.Generated.cs:line 2875 at Microsoft.CodeAnalysis.CSharp.LocalRewriter.Visit(BoundNode node) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Lowering\LocalRewriter\LocalRewriter.cs:line 145 at Microsoft.CodeAnalysis.CSharp.LocalRewriter.VisitForStatement(BoundForStatement node) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Lowering\LocalRewriter\LocalRewriter_ForStatement.cs:line 18 at Microsoft.CodeAnalysis.CSharp.BoundForStatement.Accept(BoundTreeVisitor visitor) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Generated\BoundNodes.xml.Generated.cs:line 3421 at Microsoft.CodeAnalysis.CSharp.LocalRewriter.Visit(BoundNode node) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Lowering\LocalRewriter\LocalRewriter.cs:line 145 at Microsoft.CodeAnalysis.CSharp.LocalRewriter.VisitBlock(BoundBlock node) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Lowering\LocalRewriter\LocalRewriter_Block.cs:line 23 at Microsoft.CodeAnalysis.CSharp.BoundBlock.Accept(BoundTreeVisitor visitor) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Generated\BoundNodes.xml.Generated.cs:line 2485 at Microsoft.CodeAnalysis.CSharp.LocalRewriter.Visit(BoundNode node) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Lowering\LocalRewriter\LocalRewriter.cs:line 145 at Microsoft.CodeAnalysis.CSharp.LocalRewriter.Rewrite(CSharpCompilation compilation, MethodSymbol method, Int32 methodOrdinal, NamedTypeSymbol containingType, BoundStatement statement, TypeCompilationState compilationState, SynthesizedSubmissionFields previousSubmissionFields, Boolean allowOmissionOfConditionalCalls, Boolean instrumentForDynamicAnalysis, ImmutableArray`1& dynamicAnalysisSpans, DebugDocumentProvider debugDocumentProvider, DiagnosticBag diagnostics, Boolean& sawLambdas, Boolean& sawLocalFunctions, Boolean& sawAwaitInExceptionHandler) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Lowering\LocalRewriter\LocalRewriter.cs:line 97 at Microsoft.CodeAnalysis.CSharp.MethodCompiler.LowerBodyOrInitializer(MethodSymbol method, Int32 methodOrdinal, BoundStatement body, SynthesizedSubmissionFields previousSubmissionFields, TypeCompilationState compilationState, Boolean instrumentForDynamicAnalysis, DebugDocumentProvider debugDocumentProvider, ImmutableArray`1& dynamicAnalysisSpans, DiagnosticBag diagnostics, VariableSlotAllocator& lazyVariableSlotAllocator, ArrayBuilder`1 lambdaDebugInfoBuilder, ArrayBuilder`1 closureDebugInfoBuilder, StateMachineTypeSymbol& stateMachineTypeOpt) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Compiler\MethodCompiler.cs:line 1259 at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileMethod(MethodSymbol methodSymbol, Int32 methodOrdinal, ProcessedFieldInitializers& processedInitializers, SynthesizedSubmissionFields previousSubmissionFields, TypeCompilationState compilationState) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Compiler\MethodCompiler.cs:line 1088 at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileNamedType(NamedTypeSymbol containingType) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Compiler\MethodCompiler.cs:line 498 at Microsoft.CodeAnalysis.CSharp.MethodCompiler.<>c__DisplayClass21_0.<CompileNamedTypeAsTask>b__0() in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Compiler\MethodCompiler.cs:line 388 at Roslyn.Utilities.UICultureUtilities.<>c__DisplayClass5_0.<WithCurrentUICulture>b__0() in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\Core\Portable\InternalUtilities\UICultureUtilities.cs:line 136 at System.Threading.Tasks.Task.InnerInvoke() at System.Threading.Tasks.Task.Execute() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at Microsoft.CodeAnalysis.CSharp.MethodCompiler.WaitForWorkers() in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Compiler\MethodCompiler.cs:line 303 at Microsoft.CodeAnalysis.CSharp.MethodCompiler.CompileMethodBodies(CSharpCompilation compilation, PEModuleBuilder moduleBeingBuiltOpt, Boolean emittingPdb, Boolean emitTestCoverageData, Boolean hasDeclarationErrors, DiagnosticBag diagnostics, Predicate`1 filterOpt, CancellationToken cancellationToken) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Compiler\MethodCompiler.cs:line 144 at Microsoft.CodeAnalysis.CSharp.CSharpCompilation.CompileMethods(CommonPEModuleBuilder moduleBuilder, Boolean emittingPdb, Boolean emitMetadataOnly, Boolean emitTestCoverageData, DiagnosticBag diagnostics, Predicate`1 filterOpt, CancellationToken cancellationToken) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\CSharp\Portable\Compilation\CSharpCompilation.cs:line 2626 at Microsoft.CodeAnalysis.Compilation.Emit(Stream peStream, Stream metadataPEStream, Stream pdbStream, Stream xmlDocumentationStream, Stream win32Resources, IEnumerable`1 manifestResources, EmitOptions options, IMethodSymbol debugEntryPoint, Stream sourceLinkStream, IEnumerable`1 embeddedTexts, CompilationTestData testData, CancellationToken cancellationToken) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\Core\Portable\Compilation\Compilation.cs:line 2387 at Microsoft.CodeAnalysis.Compilation.Emit(Stream peStream, Stream pdbStream, Stream xmlDocumentationStream, Stream win32Resources, IEnumerable`1 manifestResources, EmitOptions options, IMethodSymbol debugEntryPoint, Stream sourceLinkStream, IEnumerable`1 embeddedTexts, Stream metadataPEStream, CancellationToken cancellationToken) in D:\$TC\work\142fd509662c8cdc\!roslyn\sources\dotnet\src\Compilers\Core\Portable\Compilation\Compilation.cs:line 2335 at SharpLab.Server.Compilation.Compiler.<TryCompileToStreamAsync>d__1.MoveNext() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd(Task task) at SharpLab.Server.MirrorSharp.SlowUpdate.<ProcessAsync>d__7.MoveNext() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at MirrorSharp.Internal.Handlers.SlowUpdateHandler.<ExecuteAsync>d__4.MoveNext() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd(Task task) at MirrorSharp.Internal.Connection.<ReceiveAndProcessInternalAsync>d__13.MoveNext() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at MirrorSharp.Internal.Connection.<ReceiveAndProcessAsync>d__12.MoveNext()

[jcouv]

This was fixed (by #32850)
I'll add a test to verify and close