GenAPI fails to generate source for latest Corelib

[ericstj]

Describe the bug

GenAPI fails when generating source for the latest CoreLib:

Unhandled exception: System.ArgumentException: Unknown operator kind. (Parameter 'System.Half.explicit operator checked byte(System.Half)')
   at Microsoft.DotNet.GenAPI.SyntaxGeneratorExtensions.DeclarationExt(SyntaxGenerator syntaxGenerator, ISymbol symbol, ISymbolFilter symbolFilter) in /_/src/Compatibility/GenAPI/Microsoft.DotNet.GenAPI/SyntaxGeneratorExtensions.cs:line 107
   at Microsoft.DotNet.GenAPI.CSharpFileBuilder.Visit(SyntaxNode namedTypeNode, INamedTypeSymbol namedType) in /_/src/Compatibility/GenAPI/Microsoft.DotNet.GenAPI/CSharpFileBuilder.cs:line 211
   at Microsoft.DotNet.GenAPI.CSharpFileBuilder.Visit(INamespaceSymbol namespaceSymbol) in /_/src/Compatibility/GenAPI/Microsoft.DotNet.GenAPI/CSharpFileBuilder.cs:line 118
   at Microsoft.DotNet.GenAPI.CSharpFileBuilder.WriteAssembly(IAssemblySymbol assemblySymbol) in /_/src/Compatibility/GenAPI/Microsoft.DotNet.GenAPI/CSharpFileBuilder.cs:line 72
   at Microsoft.DotNet.GenAPI.GenAPIApp.Run(ILog logger, String[] assemblies, String[] assemblyReferences, String outputPath, String headerFile, String exceptionMessage, String[] excludeApiFiles, String[] excludeAttributesFiles, Boolean respectInternals, Boolean includeAssemblyAttributes) in /_/src/Compatibility/GenAPI/Microsoft.DotNet.GenAPI/GenAPIApp.cs:line 86
   at Microsoft.DotNet.GenAPI.Tool.Program.<>c__DisplayClass0_0.<Main>b__0(ParseResult parseResult) in /_/src/Compatibility/GenAPI/Microsoft.DotNet.GenAPI.Tool/Program.cs:line 100
   at System.CommandLine.CliCommand.<>c__DisplayClass30_0.<SetAction>b__0(ParseResult context)
   at System.CommandLine.Invocation.AnonymousSynchronousCliAction.Invoke(ParseResult parseResult)
   at System.CommandLine.Invocation.InvocationPipeline.Invoke(ParseResult parseResult)

To Reproduce

dotnet tool install -g microsoft.dotnet.genapi.tool --add-source https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet9-transport/nuget/v3/index.json --prerelease
genapi --assembly C:\Program Files\dotnet\shared\Microsoft.NETCore.App\8.0.4\System.Private.CoreLib.dll --output-path c:\scratch\spc\spc.cs

Exceptions (if any)

System.ArgumentException: Unknown operator kind

[ericstj]

Same thing repros for System.Runtime.

Appears to be this bug: dotnet/roslyn#63410

[ViktorHofer]

Given that this got fixed recently in roslyn, we should rerun the above repro steps with the latest available GenAPI tooling.

[ViktorHofer]

Interestingly this still repros with the latest GenAPI that bundles roslyn assemblies from this SHA: dotnet/roslyn@84c5476

Same stack trace