Revert

CyrusNajmabadi · CyrusNajmabadi · commit 580ac031dfee · 2025-10-17T12:11:05.000+02:00
diff --git a/src/Compilers/CSharp/Portable/Binder/Binder_Conversions.cs b/src/Compilers/CSharp/Portable/Binder/Binder_Conversions.cs
@@ -2464,7 +2464,7 @@ private BoundExpression CreateTupleLiteralConversion(SyntaxNode syntax, BoundTup
                         locationBuilder.Add(argument.NameColon?.Name.Location);
                     }
 
-                    targetType = targetType.WithElementNames(sourceTuple.ArgumentNamesOpt,
+                    targetType = targetType.WithElementNames(sourceTuple.ArgumentNamesOpt!,
                         locationBuilder.ToImmutableAndFree(),
                         errorPositions: default,
                         ImmutableArray.Create(tupleSyntax.Location));
diff --git a/src/Compilers/CSharp/Portable/Binder/Binder_Deconstruct.cs b/src/Compilers/CSharp/Portable/Binder/Binder_Deconstruct.cs
@@ -717,7 +717,7 @@ private BoundBadExpression MissingDeconstruct(BoundExpression receiver, SyntaxNo
         {
             if (receiver.Type?.IsErrorType() == false)
             {
-                Error(diagnostics, ErrorCode.ERR_MissingDeconstruct, rightSyntax, receiver.Type, numParameters);
+                Error(diagnostics, ErrorCode.ERR_MissingDeconstruct, rightSyntax, receiver.Type!, numParameters);
             }
 
             outPlaceholders = default;
diff --git a/src/Compilers/CSharp/Portable/Binder/BindingDiagnosticBag.cs b/src/Compilers/CSharp/Portable/Binder/BindingDiagnosticBag.cs
@@ -140,7 +140,7 @@ void addAssembliesUsedByNamespaceReferenceImpl(NamespaceSymbol ns)
 
                     if (containingAssembly?.IsMissing == false)
                     {
-                        DependenciesBag.Add(containingAssembly);
+                        DependenciesBag!.Add(containingAssembly);
                     }
                 }
             }
@@ -162,7 +162,7 @@ internal CSDiagnosticInfo Add(ErrorCode code, SyntaxNode syntax, params object[]
             => Add(code, syntax.Location, args);
 
         internal CSDiagnosticInfo Add(ErrorCode code, SyntaxToken syntax, params object[] args)
-            => Add(code, syntax.GetLocation(), args);
+            => Add(code, syntax.GetLocation()!, args);
 
         internal CSDiagnosticInfo Add(ErrorCode code, Location location, params object[] args)
         {
diff --git a/src/Compilers/CSharp/Portable/Binder/RefSafetyAnalysis.cs b/src/Compilers/CSharp/Portable/Binder/RefSafetyAnalysis.cs
@@ -764,7 +764,7 @@ private void VisitArgumentsAndGetArgumentPlaceholders(BoundExpression? receiverO
                 {
                     visitArguments(nodeAndInvocationInfo.call, in nodeAndInvocationInfo.methodInvocationInfo);
                 }
-                while (calls.TryPop(out nodeAndInvocationInfo));
+                while (calls.TryPop(out nodeAndInvocationInfo!));
 
                 calls.Free();
             }
diff --git a/src/Compilers/CSharp/Portable/BoundTree/LengthBasedStringSwitchData.cs b/src/Compilers/CSharp/Portable/BoundTree/LengthBasedStringSwitchData.cs
@@ -273,15 +273,15 @@ public string Dump()
             {
                 builder.AppendLine($"Label {readable(charJumpTable.Label)}:");
                 builder.AppendLine($"  Selected char position: {charJumpTable.SelectedCharPosition}:");
-                dump(charJumpTable.CharCaseLabels);
+                dump(charJumpTable.CharCaseLabels!);
             }
             builder.AppendLine();
 
             builder.AppendLine("String dispatches:");
             foreach (var stringJumpTable in StringBasedJumpTables)
             {
                 builder.AppendLine($"Label {readable(stringJumpTable.Label)}:");
-                dump(stringJumpTable.StringCaseLabels);
+                dump(stringJumpTable.StringCaseLabels!);
             }
             builder.AppendLine();
 
diff --git a/src/Compilers/CSharp/Portable/Lowering/DiagnosticsPass_ExpressionTrees.cs b/src/Compilers/CSharp/Portable/Lowering/DiagnosticsPass_ExpressionTrees.cs
@@ -90,7 +90,7 @@ public override BoundNode VisitArrayAccess(BoundArrayAccess node)
         {
             if (_inExpressionLambda &&
                 node.Indices.Length == 1 &&
-                !node.Indices[0].Type.SpecialType.CanOptimizeBehavior())
+                !node.Indices[0].Type!.SpecialType.CanOptimizeBehavior())
             {
                 Error(ErrorCode.ERR_ExpressionTreeContainsPatternImplicitIndexer, node);
             }
diff --git a/src/Compilers/CSharp/Portable/Symbols/NamedTypeSymbol.cs b/src/Compilers/CSharp/Portable/Symbols/NamedTypeSymbol.cs
@@ -26,7 +26,7 @@ internal abstract partial class NamedTypeSymbol : TypeSymbol, INamedTypeSymbolIn
     {
         private bool _hasNoBaseCycles;
 
-        private static readonly ImmutableSegmentedDictionary<string, Symbol> RequiredMembersErrorSentinel = ImmutableSegmentedDictionary<string, Symbol>.Empty.Add("<error sentinel>", null);
+        private static readonly ImmutableSegmentedDictionary<string, Symbol> RequiredMembersErrorSentinel = ImmutableSegmentedDictionary<string, Symbol>.Empty.Add("<error sentinel>", null!);
 
         /// <summary>
         /// <see langword="default"/> if uninitialized. <see cref="RequiredMembersErrorSentinel"/> if there are errors. <see cref="ImmutableSegmentedDictionary{TKey, TValue}.Empty"/> if
diff --git a/src/Compilers/CSharp/Portable/Symbols/ReferenceManager.cs b/src/Compilers/CSharp/Portable/Symbols/ReferenceManager.cs
@@ -505,7 +505,7 @@ private bool CreateAndSetSourceAssemblyFullBind(CSharpCompilation compilation)
                                     implicitReferenceResolutions,
                                     hasCircularReference,
                                     resolutionDiagnostics.ToReadOnly(),
-                                    ReferenceEquals(corLibrary, assemblySymbol) ? null : corLibrary, // https://github.com/dotnet/roslyn/issues/40751 Unnecessary suppression
+                                    ReferenceEquals(corLibrary, assemblySymbol) ? null! : corLibrary, // https://github.com/dotnet/roslyn/issues/40751 Unnecessary suppression
                                     modules,
                                     moduleReferences,
                                     assemblySymbol.SourceModule.GetReferencedAssemblySymbols(),
diff --git a/src/Compilers/CSharp/Portable/Symbols/Source/SourceMemberContainerSymbol.cs b/src/Compilers/CSharp/Portable/Symbols/Source/SourceMemberContainerSymbol.cs
@@ -3535,7 +3535,7 @@ public void Free()
                 AddDeclarationDiagnostics(diagnostics);
                 diagnostics.Free();
 
-                return declaredMembersAndInitializers;
+                return declaredMembersAndInitializers!;
             }
 
             // Builds explicitly declared members (as opposed to synthesized members).
diff --git a/src/Compilers/CSharp/Portable/Symbols/Synthesized/SynthesizedEntryPointSymbol.cs b/src/Compilers/CSharp/Portable/Symbols/Synthesized/SynthesizedEntryPointSymbol.cs
@@ -373,7 +373,7 @@ internal AsyncForwardEntryPoint(CSharpCompilation compilation, NamedTypeSymbol c
                 { WasCompilerGenerated = true };
 
                 // The diagnostics that would be produced here will already have been captured and returned.
-                var success = binder.GetAwaitableExpressionInfo(userMainInvocation, out _getAwaiterGetResultCall, runtimeAsyncAwaitCall: out _, _userMainReturnTypeSyntax, BindingDiagnosticBag.Discarded);
+                var success = binder.GetAwaitableExpressionInfo(userMainInvocation, out _getAwaiterGetResultCall!, runtimeAsyncAwaitCall: out _, _userMainReturnTypeSyntax, BindingDiagnosticBag.Discarded);
 
                 Debug.Assert(
                     ReturnType.IsVoidType() ||
diff --git a/src/Compilers/CSharp/Portable/Symbols/Tuples/TupleTypeSymbol.cs b/src/Compilers/CSharp/Portable/Symbols/Tuples/TupleTypeSymbol.cs
@@ -863,7 +863,7 @@ private TypeSymbol MergeTupleNames(NamedTypeSymbol other, NamedTypeSymbol merged
             else
             {
                 Debug.Assert(names1.Length == names2.Length);
-                mergedNames = names1.ZipAsArray(names2, (n1, n2) => string.CompareOrdinal(n1, n2) == 0 ? n1 : null);
+                mergedNames = names1.ZipAsArray(names2, (n1, n2) => string.CompareOrdinal(n1, n2) == 0 ? n1 : null)!;
 
                 if (mergedNames.All(n => n is null))
                 {
diff --git a/src/Compilers/CSharp/Test/Emit3/Semantics/ExtensionTests.cs b/src/Compilers/CSharp/Test/Emit3/Semantics/ExtensionTests.cs
@@ -51662,7 +51662,7 @@ public override void Initialize(AnalysisContext context)
             void handle(SyntaxNodeAnalysisContext context)
             {
                 _results.Enqueue(print(context));
-                Assert.Same(context.Node.SyntaxTree, context.ContainingSymbol.DeclaringSyntaxReferences.Single().SyntaxTree);
+                Assert.Same(context.Node.SyntaxTree, context.ContainingSymbol!.DeclaringSyntaxReferences.Single().SyntaxTree);
             }
 
             static string print(SyntaxNodeAnalysisContext context)
diff --git a/src/Compilers/CSharp/Test/Emit3/Semantics/PrimaryConstructorTests.cs b/src/Compilers/CSharp/Test/Emit3/Semantics/PrimaryConstructorTests.cs
@@ -5299,7 +5299,7 @@ protected void Handle1(SyntaxNodeAnalysisContext context)
                         break;
                 }
 
-                Assert.Same(literal.SyntaxTree, context.ContainingSymbol.DeclaringSyntaxReferences.Single().SyntaxTree);
+                Assert.Same(literal.SyntaxTree, context.ContainingSymbol!.DeclaringSyntaxReferences.Single().SyntaxTree);
             }
 
             protected void Handle2(SyntaxNodeAnalysisContext context)
@@ -5317,7 +5317,7 @@ protected void Handle2(SyntaxNodeAnalysisContext context)
                         break;
                 }
 
-                Assert.Same(equalsValue.SyntaxTree, context.ContainingSymbol.DeclaringSyntaxReferences.Single().SyntaxTree);
+                Assert.Same(equalsValue.SyntaxTree, context.ContainingSymbol!.DeclaringSyntaxReferences.Single().SyntaxTree);
             }
 
             protected void Handle3(SyntaxNodeAnalysisContext context)
@@ -5335,7 +5335,7 @@ protected void Handle3(SyntaxNodeAnalysisContext context)
                         break;
                 }
 
-                Assert.Same(initializer.SyntaxTree, context.ContainingSymbol.DeclaringSyntaxReferences.Single().SyntaxTree);
+                Assert.Same(initializer.SyntaxTree, context.ContainingSymbol!.DeclaringSyntaxReferences.Single().SyntaxTree);
             }
 
             protected void Handle4(SyntaxNodeAnalysisContext context)
@@ -5364,7 +5364,7 @@ protected void Handle6(SyntaxNodeAnalysisContext context)
                         break;
                 }
 
-                Assert.Same(record.SyntaxTree, context.ContainingSymbol.DeclaringSyntaxReferences.Single().SyntaxTree);
+                Assert.Same(record.SyntaxTree, context.ContainingSymbol!.DeclaringSyntaxReferences.Single().SyntaxTree);
             }
 
             protected void Handle7(SyntaxNodeAnalysisContext context)
diff --git a/src/Compilers/CSharp/Test/Semantic/Semantics/DelegateTypeTests.cs b/src/Compilers/CSharp/Test/Semantic/Semantics/DelegateTypeTests.cs
@@ -12191,7 +12191,7 @@ static void speculate(SemanticModel? model, int position, string text, string ex
                 var stmt = SyntaxFactory.ParseStatement(text);
                 Assert.True(model.TryGetSpeculativeSemanticModel(position, stmt, out model));
                 var expr = ((ExpressionStatementSyntax)stmt).Expression;
-                var type = model.GetTypeInfo(expr).Type;
+                var type = model!.GetTypeInfo(expr).Type;
                 Assert.Equal(expectedDelegateType, type.ToTestDisplayString());
             }
 
diff --git a/src/Compilers/CSharp/Test/Semantic/SourceGeneration/GeneratorDriverFuzzTests.cs b/src/Compilers/CSharp/Test/Semantic/SourceGeneration/GeneratorDriverFuzzTests.cs
@@ -352,7 +352,7 @@ void registerPipeline(IncrementalGeneratorInitializationContext context)
 
                 context.RegisterSourceOutput(finalProvider, (context, text) =>
                 {
-                    context.AddSource(((InMemoryAdditionalText)text).Path, ((InMemoryAdditionalText)text).GetText().ToString());
+                    context.AddSource(((InMemoryAdditionalText)text).Path, ((InMemoryAdditionalText)text).GetText()!.ToString());
                 });
             }
 
diff --git a/src/Compilers/Core/Portable/Collections/CachingFactory.cs b/src/Compilers/Core/Portable/Collections/CachingFactory.cs
@@ -83,7 +83,7 @@ public bool TryGetValue(TKey key, [MaybeNullWhen(returnValue: false)] out TValue
                 }
             }
 
-            value = default;
+            value = default!;
             return false;
         }
 
@@ -170,7 +170,7 @@ public bool TryGetValue(TKey key, [MaybeNullWhen(returnValue: false)] out TValue
                 return true;
             }
 
-            value = default;
+            value = default!;
             return false;
         }
 
diff --git a/src/Compilers/Core/Portable/Collections/ConcurrentCache.cs b/src/Compilers/Core/Portable/Collections/ConcurrentCache.cs
@@ -69,7 +69,7 @@ public bool TryGetValue(TKey key, [MaybeNullWhen(returnValue: false)] out TValue
                 return true;
             }
 
-            value = default;
+            value = default!;
             return false;
         }
     }
diff --git a/src/Compilers/Core/Portable/Collections/KeyedStack.cs b/src/Compilers/Core/Portable/Collections/KeyedStack.cs
@@ -38,7 +38,7 @@ public bool TryPop(T key, [MaybeNullWhen(returnValue: false)] out R value)
                 return true;
             }
 
-            value = default(R);
+            value = default(R)!;
             return false;
         }
     }
diff --git a/src/Compilers/Core/Portable/Collections/SmallDictionary.cs b/src/Compilers/Core/Portable/Collections/SmallDictionary.cs
@@ -72,10 +72,10 @@ public bool TryGetValue(K key, [MaybeNullWhen(returnValue: false)] out V value)
         {
             if (_root != null)
             {
-                return TryGetValue(GetHashCode(key), key, out value);
+                return TryGetValue(GetHashCode(key), key, out value!);
             }
 
-            value = default;
+            value = default!;
             return false;
         }
 
@@ -219,7 +219,7 @@ private bool TryGetValue(int hashCode, K key, [MaybeNullWhen(returnValue: false)
                 }
             } while (b != null);
 
-            value = default;
+            value = default!;
             return false;
 
 hasBucket:
@@ -229,7 +229,7 @@ private bool TryGetValue(int hashCode, K key, [MaybeNullWhen(returnValue: false)
                 return true;
             }
 
-            return GetFromList(b.Next, key, out value);
+            return GetFromList(b.Next, key, out value!);
         }
 
         private bool GetFromList(Node? next, K key, [MaybeNullWhen(returnValue: false)] out V value)
@@ -245,7 +245,7 @@ private bool GetFromList(Node? next, K key, [MaybeNullWhen(returnValue: false)]
                 next = next.Next;
             }
 
-            value = default;
+            value = default!;
             return false;
         }
 
diff --git a/src/Compilers/Core/Portable/CommandLine/CommonCompiler.cs b/src/Compilers/Core/Portable/CommandLine/CommonCompiler.cs
@@ -217,7 +217,7 @@ internal virtual Func<string, MetadataReferenceProperties, PortableExecutableRef
 
         internal virtual MetadataReferenceResolver GetCommandLineMetadataReferenceResolver(TouchedFileLogger? loggerOpt)
         {
-            var pathResolver = new CompilerRelativePathResolver(FileSystem, Arguments.ReferencePaths, Arguments.BaseDirectory);
+            var pathResolver = new CompilerRelativePathResolver(FileSystem, Arguments.ReferencePaths, Arguments.BaseDirectory!);
             return new LoggingMetadataFileReferenceResolver(pathResolver, GetMetadataProvider(), loggerOpt);
         }
 
diff --git a/src/Compilers/Core/Portable/DiagnosticAnalyzer/AnalyzerFileReference.cs b/src/Compilers/Core/Portable/DiagnosticAnalyzer/AnalyzerFileReference.cs
@@ -262,7 +262,7 @@ private static ImmutableArray<string> GetSupportedLanguages(TypeDefinition typeD
             ImmutableArray<string> result = [];
             foreach (CustomAttributeHandle customAttrHandle in typeDef.GetCustomAttributes())
             {
-                if (peModule.IsTargetAttribute(customAttrHandle, attributeType.Namespace, attributeType.Name, ctor: out _))
+                if (peModule.IsTargetAttribute(customAttrHandle, attributeType.Namespace!, attributeType.Name, ctor: out _))
                 {
                     if (languagesFunc(peModule, customAttrHandle) is { } attributeSupportedLanguages)
                     {
diff --git a/src/Compilers/Core/Portable/DiagnosticAnalyzer/AsyncQueue.cs b/src/Compilers/Core/Portable/DiagnosticAnalyzer/AsyncQueue.cs
@@ -307,7 +307,7 @@ private static void AttachCancellation<T>(TaskCompletionSource<T> taskCompletion
             cancelableTaskCompletionSource.CancellationTokenRegistration = cancellationToken.Register(
                 static s =>
                 {
-                    var t = (CancelableTaskCompletionSource<T>)s;
+                    var t = (CancelableTaskCompletionSource<T>)s!;
                     t.TaskCompletionSource.TrySetCanceled(t.CancellationToken);
                 },
                 cancelableTaskCompletionSource,
@@ -317,7 +317,7 @@ private static void AttachCancellation<T>(TaskCompletionSource<T> taskCompletion
             taskCompletionSource.Task.ContinueWith(
                 static (_, s) =>
                 {
-                    var t = (CancelableTaskCompletionSource<T>)s;
+                    var t = (CancelableTaskCompletionSource<T>)s!;
                     t.CancellationTokenRegistration.Dispose();
                 },
                 cancelableTaskCompletionSource,
diff --git a/src/Compilers/Core/Portable/Emit/CommonPEModuleBuilder.cs b/src/Compilers/Core/Portable/Emit/CommonPEModuleBuilder.cs
@@ -631,7 +631,7 @@ public int GetTypeDefinitionGeneration(Cci.INamedTypeDefinition typeDef)
         {
             if (PreviousGeneration != null)
             {
-                var symbolChanges = EncSymbolChanges;
+                var symbolChanges = EncSymbolChanges!;
                 if (symbolChanges.IsReplacedDef(typeDef))
                 {
                     // Type emitted with Replace semantics in this delta, it's name should have the current generation ordinal suffix.
diff --git a/src/Compilers/Core/Portable/InternalUtilities/ConcurrentLruCache.cs b/src/Compilers/Core/Portable/InternalUtilities/ConcurrentLruCache.cs
@@ -183,7 +183,7 @@ public bool UnsafeTryGetValue(K key, [MaybeNullWhen(returnValue: false)] out V v
             }
             else
             {
-                value = default;
+                value = default!;
                 return false;
             }
         }
diff --git a/src/Compilers/Core/Portable/InternalUtilities/ConsList`1.cs b/src/Compilers/Core/Portable/InternalUtilities/ConsList`1.cs
@@ -51,7 +51,7 @@ public bool MoveNext()
                 {
                     // Suppress false positive CS8717 reported for MaybeNull assignment to AllowNull
                     // https://github.com/dotnet/roslyn/issues/38926
-                    _current = currentTail._head;
+                    _current = currentTail._head!;
                     _tail = newTail;
                     return true;
                 }
diff --git a/src/Compilers/Core/Portable/InternalUtilities/TextKeyedCache.cs b/src/Compilers/Core/Portable/InternalUtilities/TextKeyedCache.cs
@@ -138,7 +138,7 @@ public void Free()
                 return tk;
             }
 
-            return null;
+            return null!;
         }
 
         private SharedEntryValue? FindSharedEntry(ReadOnlySpan<char> chars, int hashCode)
diff --git a/src/Compilers/Core/Portable/MetadataReader/PEModule.cs b/src/Compilers/Core/Portable/MetadataReader/PEModule.cs
@@ -1555,10 +1555,10 @@ internal bool HasAttributeUsageAttribute(EntityHandle token, IAttributeNamedArgu
                                     switch (namedArgValues.nameValuePair.Key)
                                     {
                                         case "AllowMultiple":
-                                            allowMultiple = (bool)namedArgValues.nameValuePair.Value.ValueInternal;
+                                            allowMultiple = (bool)namedArgValues.nameValuePair.Value.ValueInternal!;
                                             break;
                                         case "Inherited":
-                                            inherited = (bool)namedArgValues.nameValuePair.Value.ValueInternal;
+                                            inherited = (bool)namedArgValues.nameValuePair.Value.ValueInternal!;
                                             break;
                                     }
                                 }
diff --git a/src/Compilers/Core/Portable/Operations/ControlFlowGraph.cs b/src/Compilers/Core/Portable/Operations/ControlFlowGraph.cs
@@ -313,7 +313,7 @@ internal bool TryGetAnonymousFunctionControlFlowGraph(IFlowAnonymousFunctionOper
             }
 
             controlFlowGraph = anonymousFlowGraph;
-            Debug.Assert(controlFlowGraph.Parent == this);
+            Debug.Assert(controlFlowGraph!.Parent == this);
             return true;
         }
     }
diff --git a/src/Compilers/Core/Portable/Operations/ControlFlowGraphBuilder.cs b/src/Compilers/Core/Portable/Operations/ControlFlowGraphBuilder.cs
@@ -2690,7 +2690,7 @@ private IOperation VisitShortCircuitingOperator(IBinaryOperation condition, bool
                 AppendNewBlock(lazyFallThrough);
 
                 var constantValue = ConstantValue.Create(stopValue);
-                SyntaxNode leftSyntax = (lazyFallThrough.GetSingletonPredecessorOrDefault() != null ? condition.LeftOperand : condition).Syntax;
+                SyntaxNode leftSyntax = (lazyFallThrough!.GetSingletonPredecessorOrDefault() != null ? condition.LeftOperand : condition).Syntax;
                 AddStatement(new FlowCaptureOperation(captureId, leftSyntax, new LiteralOperation(semanticModel: null, leftSyntax, condition.Type, constantValue, isImplicit: true)));
 
                 AppendNewBlock(labEnd);
diff --git a/src/Compilers/Core/Portable/Syntax/SyntaxNavigator.cs b/src/Compilers/Core/Portable/Syntax/SyntaxNavigator.cs
@@ -385,7 +385,7 @@ private SyntaxToken GetNextToken(
                 {
                     if (trivia.TryGetStructure(out var structure) && stepInto != null && stepInto(trivia))
                     {
-                        var token = GetFirstToken(structure, predicate, stepInto);
+                        var token = GetFirstToken(structure!, predicate, stepInto);
                         if (token.RawKind != None)
                         {
                             return token;
diff --git a/src/Compilers/Core/Portable/Syntax/SyntaxNode.cs b/src/Compilers/Core/Portable/Syntax/SyntaxNode.cs
@@ -254,7 +254,7 @@ internal SyntaxNode GetWeakRedElement(ref WeakReference<SyntaxNode>? slot, int i
             SyntaxNode? value = null;
             if (slot?.TryGetTarget(out value) == true)
             {
-                return value;
+                return value!;
             }
 
             return CreateWeakItem(ref slot, index);
@@ -273,7 +273,7 @@ private SyntaxNode CreateWeakItem(ref WeakReference<SyntaxNode>? slot, int index
                 WeakReference<SyntaxNode>? previousWeakReference = slot;
                 if (previousWeakReference?.TryGetTarget(out previousNode) == true)
                 {
-                    return previousNode;
+                    return previousNode!;
                 }
 
                 if (Interlocked.CompareExchange(ref slot, newWeakReference, previousWeakReference) == previousWeakReference)
diff --git a/src/Compilers/Core/Portable/Syntax/SyntaxNodeOrToken.cs b/src/Compilers/Core/Portable/Syntax/SyntaxNodeOrToken.cs
@@ -170,7 +170,7 @@ internal bool AsToken(out SyntaxToken token)
         {
             if (IsToken)
             {
-                token = AsToken();
+                token = AsToken()!;
                 return true;
             }
 
diff --git a/src/Compilers/Server/VBCSCompilerTests/NamedPipeTestUtil.cs b/src/Compilers/Server/VBCSCompilerTests/NamedPipeTestUtil.cs
diff --git a/src/Compilers/Shared/BuildClient.cs b/src/Compilers/Shared/BuildClient.cs
diff --git a/src/Compilers/Shared/BuildServerConnection.cs b/src/Compilers/Shared/BuildServerConnection.cs
diff --git a/src/Compilers/Test/Core/TargetFrameworkUtil.cs b/src/Compilers/Test/Core/TargetFrameworkUtil.cs
diff --git a/src/Compilers/Test/Core/TestableCompiler.cs b/src/Compilers/Test/Core/TestableCompiler.cs
diff --git a/src/Compilers/Test/Utilities/CSharp/FunctionPointerUtilities.cs b/src/Compilers/Test/Utilities/CSharp/FunctionPointerUtilities.cs
diff --git a/src/Compilers/Test/Utilities/CSharp/TestAttributesVisitor.cs b/src/Compilers/Test/Utilities/CSharp/TestAttributesVisitor.cs

Original file line number	Diff line number	Diff line change
`@@ -2464,7 +2464,7 @@ private BoundExpression CreateTupleLiteralConversion(SyntaxNode syntax, BoundTup`
`2464`	`2464`	`locationBuilder.Add(argument.NameColon?.Name.Location);`
`2465`	`2465`	`}`
`2466`	`2466`
`2467`		`- targetType = targetType.WithElementNames(sourceTuple.ArgumentNamesOpt,`
	`2467`	`+ targetType = targetType.WithElementNames(sourceTuple.ArgumentNamesOpt!,`
`2468`	`2468`	`locationBuilder.ToImmutableAndFree(),`
`2469`	`2469`	`errorPositions: default,`
`2470`	`2470`	`ImmutableArray.Create(tupleSyntax.Location));`
Original file line number	Diff line number	Diff line change
`@@ -717,7 +717,7 @@ private BoundBadExpression MissingDeconstruct(BoundExpression receiver, SyntaxNo`
`717`	`717`	`{`
`718`	`718`	`if (receiver.Type?.IsErrorType() == false)`
`719`	`719`	`{`
`720`		`- Error(diagnostics, ErrorCode.ERR_MissingDeconstruct, rightSyntax, receiver.Type, numParameters);`
	`720`	`+ Error(diagnostics, ErrorCode.ERR_MissingDeconstruct, rightSyntax, receiver.Type!, numParameters);`
`721`	`721`	`}`
`722`	`722`
`723`	`723`	`outPlaceholders = default;`
Original file line number	Diff line number	Diff line change
`@@ -140,7 +140,7 @@ void addAssembliesUsedByNamespaceReferenceImpl(NamespaceSymbol ns)`
`140`	`140`
`141`	`141`	`if (containingAssembly?.IsMissing == false)`
`142`	`142`	`{`
`143`		`- DependenciesBag.Add(containingAssembly);`
	`143`	`+ DependenciesBag!.Add(containingAssembly);`
`144`	`144`	`}`
`145`	`145`	`}`
`146`	`146`	`}`
`@@ -162,7 +162,7 @@ internal CSDiagnosticInfo Add(ErrorCode code, SyntaxNode syntax, params object[]`
`162`	`162`	`=> Add(code, syntax.Location, args);`
`163`	`163`
`164`	`164`	`internal CSDiagnosticInfo Add(ErrorCode code, SyntaxToken syntax, params object[] args)`
`165`		`- => Add(code, syntax.GetLocation(), args);`
	`165`	`+ => Add(code, syntax.GetLocation()!, args);`
`166`	`166`
`167`	`167`	`internal CSDiagnosticInfo Add(ErrorCode code, Location location, params object[] args)`
`168`	`168`	`{`
Original file line number	Diff line number	Diff line change
`@@ -764,7 +764,7 @@ private void VisitArgumentsAndGetArgumentPlaceholders(BoundExpression? receiverO`
`764`	`764`	`{`
`765`	`765`	`visitArguments(nodeAndInvocationInfo.call, in nodeAndInvocationInfo.methodInvocationInfo);`
`766`	`766`	`}`
`767`		`- while (calls.TryPop(out nodeAndInvocationInfo));`
	`767`	`+ while (calls.TryPop(out nodeAndInvocationInfo!));`
`768`	`768`
`769`	`769`	`calls.Free();`
`770`	`770`	`}`
Original file line number	Diff line number	Diff line change
`@@ -273,15 +273,15 @@ public string Dump()`
`273`	`273`	`{`
`274`	`274`	`builder.AppendLine($"Label {readable(charJumpTable.Label)}:");`
`275`	`275`	`builder.AppendLine($" Selected char position: {charJumpTable.SelectedCharPosition}:");`
`276`		`- dump(charJumpTable.CharCaseLabels);`
	`276`	`+ dump(charJumpTable.CharCaseLabels!);`
`277`	`277`	`}`
`278`	`278`	`builder.AppendLine();`
`279`	`279`
`280`	`280`	`builder.AppendLine("String dispatches:");`
`281`	`281`	`foreach (var stringJumpTable in StringBasedJumpTables)`
`282`	`282`	`{`
`283`	`283`	`builder.AppendLine($"Label {readable(stringJumpTable.Label)}:");`
`284`		`- dump(stringJumpTable.StringCaseLabels);`
	`284`	`+ dump(stringJumpTable.StringCaseLabels!);`
`285`	`285`	`}`
`286`	`286`	`builder.AppendLine();`
`287`	`287`
Original file line number	Diff line number	Diff line change
`@@ -90,7 +90,7 @@ public override BoundNode VisitArrayAccess(BoundArrayAccess node)`
`90`	`90`	`{`
`91`	`91`	`if (_inExpressionLambda &&`
`92`	`92`	`node.Indices.Length == 1 &&`
`93`		`- !node.Indices[0].Type.SpecialType.CanOptimizeBehavior())`
	`93`	`+ !node.Indices[0].Type!.SpecialType.CanOptimizeBehavior())`
`94`	`94`	`{`
`95`	`95`	`Error(ErrorCode.ERR_ExpressionTreeContainsPatternImplicitIndexer, node);`
`96`	`96`	`}`
Original file line number	Diff line number	Diff line change
`@@ -26,7 +26,7 @@ internal abstract partial class NamedTypeSymbol : TypeSymbol, INamedTypeSymbolIn`
`26`	`26`	`{`
`27`	`27`	`private bool _hasNoBaseCycles;`
`28`	`28`
`29`		`- private static readonly ImmutableSegmentedDictionary<string, Symbol> RequiredMembersErrorSentinel = ImmutableSegmentedDictionary<string, Symbol>.Empty.Add("<error sentinel>", null);`
	`29`	`+ private static readonly ImmutableSegmentedDictionary<string, Symbol> RequiredMembersErrorSentinel = ImmutableSegmentedDictionary<string, Symbol>.Empty.Add("<error sentinel>", null!);`
`30`	`30`
`31`	`31`	`/// <summary>`
`32`	`32`	`/// <see langword="default"/> if uninitialized. <see cref="RequiredMembersErrorSentinel"/> if there are errors. <see cref="ImmutableSegmentedDictionary{TKey, TValue}.Empty"/> if`
Original file line number	Diff line number	Diff line change
`@@ -3535,7 +3535,7 @@ public void Free()`
`3535`	`3535`	`AddDeclarationDiagnostics(diagnostics);`
`3536`	`3536`	`diagnostics.Free();`
`3537`	`3537`
`3538`		`- return declaredMembersAndInitializers;`
	`3538`	`+ return declaredMembersAndInitializers!;`
`3539`	`3539`	`}`
`3540`	`3540`
`3541`	`3541`	`// Builds explicitly declared members (as opposed to synthesized members).`