DllImportGenerator is failing in Mono llvmfullAOT

[agocke]

https://dev.azure.com/dnceng/public/_build/results?buildId=1496054

Build FAILED.

/__w/1/s/src/mono/msbuild/aot-compile.proj(19,9): error MSB3073: The command "/__w/1/s/artifacts/tests/coreclr/Linux.x64.Release/Tests/Core_Root/corerun /__w/1/s/artifacts/tests/coreclr/Linux.x64.Release/Tests/Core_Root/Microsoft.Interop.DllImportGenerator.dll" exited with code 1.
/__w/1/s/src/mono/msbuild/aot-compile.proj(19,9): error MSB3073: The command "/__w/1/s/artifacts/tests/coreclr/Linux.x64.Release/Tests/Core_Root/corerun /__w/1/s/artifacts/tests/coreclr/Linux.x64.Release/Tests/Core_Root/Microsoft.Interop.SourceGeneration.dll" exited with code 1.
    0 Warning(s)
    2 Error(s)

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[agocke]

@jkoritzinsky Looks like this was somehow caused by 84b55d9

[jkoritzinsky]

We're probably constructing Core_Root in some way that either overrides OutputPath or OutputItemType for ProjectReferences

[lambdageek]

@jkoritzinsky we should exclude DllImportGenerator from Core_Root. For the various Mono AOT testing legs, I think we AOT every assembly in Core_Root. The Mono AOT process needs to be able to resolve every assembly reference (using the Core_Root and the individual test - the search path is constructed in src/mono/msbuild/aot-compile.proj although I don't know the details of how this gets used by the runtime tests build script). In this case DllImportGenerator is in Core_Root but the various Roslyn assemblies aren't.

I think the cleanest approach would be to ensure that the DllImportGenerator assembly doesn't end up in Core_Root - after all it's needed only at build-time not run-time. (And I assume Core_Root is not used to build the tests)

[jkoritzinsky]

@lambdageek I agree with your assessment. These two assemblies should be excluded from Core_Root.