RuntimeBinder tests fail finding `IsType` method

[tarekgh]

Build Information

Build: https://dev.azure.com/dnceng-public/cbb18261-c48f-4abb-8651-8cdcb5474649/_build/results?buildId=1092408
Build error leg or test failing: Microsoft.CSharp.RuntimeBinder.Tests.AssignmentTests.AddAssignment
Pull request: #117551

Error Message

Fill the error message using step by step known issues guidance.

{
  "ErrorMessage": "Microsoft.CSharp.RuntimeBinder.RuntimeBinderException : No overload for method 'IsType' takes 2 arguments",
  "ErrorPattern": "",
  "BuildRetry": false,
  "ExcludeConsoleLog": false
}

Known issue validation

Build: 🔎 https://dev.azure.com/dnceng-public/public/_build/results?buildId=1092408
Error message validated: [Microsoft.CSharp.RuntimeBinder.RuntimeBinderException : No overload for method 'IsType' takes 2 arguments]
Result validation: ✅ Known issue matched with the provided build.
Validation performed at: 7/12/2025 12:22:49 AM UTC

Report

Build	Definition	Test	Pull Request
1095014	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117627
1094804	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution
1093723	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117542
1094814	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117650
1094768	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117611
1094755	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117458
1094738	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution
1094554	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117590
1094572	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#116682
1094481	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117578
1094413	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117635
1094361	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117630
1093666	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117427
1094337	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117629
1093890	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117596
1094240	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution
1094301	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117627
1094295	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117626
1094219	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117619
1094162	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117192
1094158	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution
1094121	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117606
1094129	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117621
1094012	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117617
1094013	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117617
1094007	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117613
1093976	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117460
1093968	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#106374
1093960	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117494
1093964	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117465
1093902	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117259
1093832	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117609
1093816	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117585
1093819	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117611
1093803	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117428
1093697	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117277
1093567	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution
1093575	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#116383
1093578	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#116383
1093548	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117600
1093528	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution
1093501	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution
1093445	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117596
1093391	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#116682
1093412	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117578
1093377	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117593
1093295	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117590
1093249	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution
1093242	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution
1093209	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117585
1092691	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117549
1093170	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117437
1093147	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117115
1093132	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117255
1093127	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117436
1093111	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117417
1093056	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution
1093065	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117580
1093034	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution
1093027	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117428
1093012	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117437
1092998	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117578
1092968	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117576
1092883	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution
1092873	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution
1092836	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117437
1092759	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117192
1092754	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117428
1092728	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution
1092722	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution
1092715	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117259
1092607	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117192
1092578	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117563
1092562	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#116943
1092555	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#113399
1092331	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117530
1092408	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117551
1092503	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution
1092450	dotnet/runtime	WasmTestOnChrome-ST-Microsoft.CSharp.Tests.WorkItemExecution	#117259

Summary

24-Hour Hit Count	7-Day Hit Count	1-Month Count
34	79	79

[dotnet-policy-service]

Tagging subscribers to 'arch-wasm': @lewing
See info in area-owners.md if you want to be subscribed.

[dotnet-policy-service]

Tagging subscribers to this area: @cston
See info in area-owners.md if you want to be subscribed.

[lewing]

cc @agocke

[lewing]

Since this is failing in EAT it is almost certainly related to trimming

[lewing]

And example of a failing test is
https://github.com/dotnet/runtime/blob/6ac6c21d0e2394031be259054607ac45ad21b962/src/libraries/Microsoft.CSharp/tests/EnumArithmeticTests.cs#L221C1-L238C10
where Assert.IsType is not preserved