NRE in Linker on dotnet/runtime perf pipeline

[radical]

Build 20220715.1, Performance Linux x64 release wasm aot micro perftiger v8 False net7.0, for dotnet-runtime-perf internal pipeline.

[2022/07/15 02:25:15][INFO] ILLink : error IL1012: IL Trimmer has encountered an unexpected error. Please report the issue at https://github.com/dotnet/linker/issues [/home/helixbot/work/AFA60946/w/C27A0A71/e/performance/artifacts/bin/for-running/MicroBenchmarks/f6eeab76-cb0e-4c5b-a534-b42263d1519d/BenchmarkDotNet.Autogenerated.csproj]
[2022/07/15 02:25:15][INFO]   Fatal error in IL Linker
[2022/07/15 02:25:15][INFO]   Unhandled exception. System.NullReferenceException: Object reference not set to an instance of an object.
[2022/07/15 02:25:15][INFO]      at Mono.Linker.TypeReferenceWalker.WalkTypeScope(MethodBody body)
[2022/07/15 02:25:15][INFO]      at Mono.Linker.TypeReferenceWalker.WalkScopes(TypeDefinition typeDefinition)
[2022/07/15 02:25:15][INFO]      at Mono.Linker.TypeReferenceWalker.WalkScopes(TypeDefinition typeDefinition)
[2022/07/15 02:25:15][INFO]      at Mono.Linker.TypeReferenceWalker.Process()
[2022/07/15 02:25:15][INFO]      at Mono.Linker.Steps.SweepStep.AssemblyReferencesCorrector.SweepAssemblyReferences(AssemblyDefinition assembly)
[2022/07/15 02:25:15][INFO]      at Mono.Linker.Steps.SweepStep.Process()
[2022/07/15 02:25:15][INFO]      at Mono.Linker.Steps.BaseStep.Process(LinkContext context)
[2022/07/15 02:25:15][INFO]      at Mono.Linker.Pipeline.ProcessStep(LinkContext context, IStep step)
[2022/07/15 02:25:15][INFO]      at Mono.Linker.Pipeline.Process(LinkContext context)
[2022/07/15 02:25:15][INFO]      at Mono.Linker.Driver.Run(ILogger customLogger)
[2022/07/15 02:25:15][INFO]      at Mono.Linker.Driver.Main(String[] args)

[marek-safar]

Duplicate of #2896

[sbomer]

@radical are there instructions on how to run that perf benchmark locally?

[radical]

You can use the instructions from #2893 (comment) .

[sbomer]

I haven't been able to reproduce this so far - I can run part of that scenario locally and I see it running the linker without errors. Right now it is failing at a later point because it's not getting the right path to v8, so maybe that is hiding the issue. Does the linker crash repro reliably for you?

Also, it seems like I needed to do:

export PERFLAB_REPO=dotnet/runtime
export PERFLAB_BRANCH=refs/heads/main

otherwise it wasn't picking up the arguments --cli-branch refs/heads/main --cli-repository https://github.com/dotnet/runtime.