CI legs failing with "Assembly 'illink' is missing dependency 'Mono.Cecil'" error

[stephentoub]

Build FAILED.

D:\a\_work\1\s\artifacts\bin\testPackages\packageTest.targets(50,5): error : Assembly 'illink' is missing dependency 'Mono.Cecil' [D:\a\_work\1\s\artifacts\bin\testPackages\projects\Microsoft.NET.ILLink\project.csproj::TargetFramework=net8.0]
    0 Warning(s)
    1 Error(s)

e.g. https://dev.azure.com/dnceng-public/public/_build/results?buildId=183607&view=logs&jobId=4590e2f8-699e-5f49-61ce-34aa015d5222&j=4590e2f8-699e-5f49-61ce-34aa015d5222&t=29f44b7b-f317-55e8-2191-80b8412b71cb

Known Issue Error Message

Fill the error message using known issues guidance.

{
  "ErrorMessage": "Assembly 'illink' is missing dependency 'Mono.Cecil'",
  "BuildRetry": false
}

Report

Build	Definition	Step Name	Console log	Pull Request
183795	dotnet/runtime	Restore and Build Product	Log	#82560
183787	dotnet/runtime	Restore and Build Product	Log	#82620
183791	dotnet/runtime	Restore and Build Product	Log	#82621
183781	dotnet/runtime	Restore and Build Product	Log	#79169
183772	dotnet/runtime	Restore and Build Product	Log	#82619
182987	dotnet/runtime	Restore and Build Product	Log	#82565
183755	dotnet/runtime	Restore and Build Product	Log	#82612
183700	dotnet/runtime	Restore and Build Product	Log	#82569
183665	dotnet/runtime	Restore and Build Product	Log	#82609
183607	dotnet/runtime	Restore and Build Product	Log	#82557
183600	dotnet/runtime	Restore and Build Product	Log	#82600
183549	dotnet/runtime	Restore and Build Product	Log	#82250
183490	dotnet/runtime	Restore and Build Product	Log	#82599
182638	dotnet/runtime	Restore and Build Product	Log	#82560
183465	dotnet/runtime	Restore and Build Product	Log	#82598
183436	dotnet/runtime	Restore and Build Product	Log	#80410
183432	dotnet/runtime	Restore and Build Product	Log	#81215
183390	dotnet/runtime	Restore and Build Product	Log	#82249
183292	dotnet/runtime	Restore and Build Product	Log	#82226
183334	dotnet/runtime	Restore and Build Product	Log	#82250
183279	dotnet/runtime	Restore and Build Product	Log
182880	dotnet/runtime	Restore and Build Product	Log	#82569
183059	dotnet/runtime	Restore and Build Product	Log	#80633
183045	dotnet/runtime	Restore and Build Product	Log	#79169
183037	dotnet/runtime	Restore and Build Product	Log	#82460
182642	dotnet/runtime	Restore and Build Product	Log	#82557
183021	dotnet/runtime	Restore and Build Product	Log	#82582
183007	dotnet/runtime	Restore and Build Product	Log	#82578
182805	dotnet/runtime	Restore and Build Product	Log	#82270
182949	dotnet/runtime	Restore and Build Product	Log	#80410
182789	dotnet/runtime	Restore and Build Product	Log	#80963
182728	dotnet/runtime	Restore and Build Product	Log	#81924
182613	dotnet/runtime	Restore and Build Product	Log	#82393

Summary

24-Hour Hit Count	7-Day Hit Count	1-Month Count
33	33	33

[ghost]

Tagging subscribers to this area: @agocke, @sbomer, @vitek-karas
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Build FAILED.

D:\a\_work\1\s\artifacts\bin\testPackages\packageTest.targets(50,5): error : Assembly 'illink' is missing dependency 'Mono.Cecil' [D:\a\_work\1\s\artifacts\bin\testPackages\projects\Microsoft.NET.ILLink\project.csproj::TargetFramework=net8.0]
    0 Warning(s)
    1 Error(s)

e.g. https://dev.azure.com/dnceng-public/public/_build/results?buildId=183607&view=logs&jobId=4590e2f8-699e-5f49-61ce-34aa015d5222&j=4590e2f8-699e-5f49-61ce-34aa015d5222&t=29f44b7b-f317-55e8-2191-80b8412b71cb

Author:	stephentoub
Assignees:	-
Labels:	untriaged, area-Tools-ILLink
Milestone:	-

[sbomer]

I think this wasn't caught in #82407 because the package validation doesn't run as part of the clr.tools subset - we should fix that. cc @tlakollo @ViktorHofer

I'm trying to fix the immediate problem in #82630.