Use SDK-selected runtime in IL SDK

[am11]

When IL SDK is publicly consumed, it is less usable on variety of platforms than the .NET SDK. The reason is a hardcoded list of runtime identifiers.

Repro:

# on alpine-x64
$ mkdir testilsdk
$ cd testilsdk
$ cat > testilsdk.ilproj <<EOF
<Project Sdk="Microsoft.NET.Sdk.IL">
  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net5.0</TargetFramework>
  </PropertyGroup>
</Project>
EOF

$ cat > global.json <<EOF
{
  "msbuild-sdks": {
    "Microsoft.NET.Sdk.IL": "5.0.0"
  }
}
EOF

$ cat > Program.il <<EOF
.assembly extern System.Runtime
{
  .publickeytoken = (B0 3F 5F 7F 11 D5 0A 3A)
}
.assembly extern System.Console { }

.assembly ConsoleApp { }

.class public auto ansi abstract sealed beforefieldinit Program extends System.Object
{
    .method public hidebysig static void Main () cil managed
    {
        .entrypoint
        .maxstack 8

        ldstr "Hello World! 👋"
        call void [System.Console]System.Console::WriteLine(string)
        ret
    }
}
EOF

$ dotnet build

which throws the following error:

/home/am11/.nuget/packages/microsoft.net.sdk.il/5.0.0/targets/Microsoft.NET.Sdk.IL.targets(139,5): error MSB3073: The command "/home/am11/.nuget/packages/runtime.linux-x64.microsoft.netcore.ilasm/5.0.0/runtimes/linux-x64/native/ilasm -QUIET -NOLOGO -EXE -OUTPUT="obj/Debug/net5.0/testilsdk.dll" Program.il" exited with code 127. [/home/am11/projects/testilsdk/testilsdk.ilproj]

The build failed. Fix the build errors and run again.

It is trying to access linux-x64, rather than linux-musl-x64.
PR fixes the problem by delegating external usages default to the runtime picked by its parent; the .NET SDK.

Workaround:

It requires us leaking the internal usage details to public and we need to explicitly pass (a very weird looking long property with) the desired runtime:

$ dotnet build -p:MicrosoftNetCoreIlasmPackageRuntimeId=linux-musl-x64
# while for the rest of the ecosystem
#     --runtime <VAL>
#     or
#     --use-curren-runtime
# suffice

[ghost]

Tagging subscribers to this area: @Anipik, @safern, @ViktorHofer
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Issue Details

---

When IL SDK is publicly consumed, it is less usable on variety of platforms than the .NET SDK. The reason is a hardcoded list of runtimes identifiers.

Repro:

# on alpine-x64
$ mkdir testilsdk
$ cd testilsdk
$ cat > testilsdk.ilproj <<EOF
<Project Sdk="Microsoft.NET.Sdk.IL">
  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net5.0</TargetFramework>
  </PropertyGroup>
</Project>
EOF

$ cat > global.json <<EOF
{
  "msbuild-sdks": {
    "Microsoft.NET.Sdk.IL": "5.0.0"
  }
}
EOF

$ cat > Program.il <<EOF
.assembly extern System.Private.CoreLib { }
.assembly extern System.Console { }

.assembly ConsoleApp { }

.class public auto ansi abstract sealed beforefieldinit Program extends System.Object
{
    .method public hidebysig static void Main () cil managed
    {
        .entrypoint
        .maxstack 8

        ldstr "Hello World! 👋"
        call void [System.Console]System.Console::WriteLine(string)
        ret
    }
}
EOF

$ dotnet build

which throws the following error:

/home/am11/.nuget/packages/microsoft.net.sdk.il/5.0.0/targets/Microsoft.NET.Sdk.IL.targets(139,5): error MSB3073: The command "/home/am11/.nuget/packages/runtime.linux-x64.microsoft.netcore.ilasm/5.0.0/runtimes/linux-x64/native/ilasm -QUIET -NOLOGO -EXE -OUTPUT="obj/Debug/net5.0/testilsdk.dll" Program.il" exited with code 127. [/home/am11/projects/testilsdk/testilsdk.ilproj]

The build failed. Fix the build errors and run again.

It is trying to access linux-x64, rather than linux-musl-x64.
PR fixes the problem by delegating external usages default to SDK picked by its parent; the .NET SDK.

Workaround:

It requires us leaking the internal usage details to public and we need to explicitly pass (a very weird looking long property with) the desired runtime:

$ dotnet build -p:MicrosoftNetCoreIlasmPackageRuntimeId=linux-musl-x64
# while for the rest of the ecosystem
#     --runtime <VAL>
#     or
#     --use-curren-runtime
# suffice

Author:	am11
Assignees:	-
Labels:	area-Infrastructure-libraries, community-contribution
Milestone:	-

[am11]

cc @ViktorHofer, @hoyosjs, one less hardcoded list (hopefully) 😁

[ViktorHofer]

This path isn't exercised by CI at the moment, as we don't use a live build of the IL SDK and because we pass in the desired RID. Approving assuming that you tested the changes locally and that the SDK property is always set (?). Presumably this will only work when the package is used in a Microsoft.NET.Sdk project that defines that property - I'm ok with that.

[am11]

@ViktorHofer, I applied this change locally (after analyzing logs produced by -v:diag) in
~/.nuget/packages/microsoft.net.sdk.il/5.0.0/targets/Microsoft.NET.Sdk.IL.targets.

After that there was another error:

/home/am11/.dotnet5/sdk/5.0.402/Microsoft.Common.CurrentVersion.targets(4521,5): error : Expected file "obj/Debug/net5.0/ref/testilsdk.dll" does not exist. [/home/am11/projects/testilsdk/testilsdk.ilproj]

The build failed. Fix the build errors and run again.

for some reason, it is looking for the compiled dll under ref/ (rather than its parent dir where it actually is). The workaround to that is:

# 1. apply this PR patch
# 2. dotnet build             <-- this will fail, but it's a prerequisite to the following workaround
# 3. cp obj/Debug/net5.0/testilsdk.dll obj/Debug/net5.0/ref/       <-- the workaround
# 4. dotnet run
Hello World! 👋

I will keep troubleshooting what is requiring ref/testilsdk.dll, but it is something not improved or regressed by this change. :)

[jkoritzinsky]

@am11 try setting <ProduceReferenceAssembly>false</ProduceReferenceAssembly> to fix the ref/ failure you’re seeing.

[ViktorHofer]

Agree with @jkoritzinsky, great observation. It's likely this code path that is triggered which shouldn't run when using the IL.SDK as roslyn isn't used: https://github.com/dotnet/msbuild/blob/35c6ef021eb745623b123307c2ebb55bf6564ef9/src/Tasks/Microsoft.Common.CurrentVersion.targets#L4647-L4657.

If that worked, feel free to add that change to the IL.SDK props/targets file :)

[am11]

Wow, that fixed it, thank you! I have set it in the Sdk.props (tested it locally by setting in ~/.nuget/packages/microsoft.net.sdk.il/5.0.0/sdk/Sdk.props (only); works on my machine. ™️

[ViktorHofer]

Thanks a lot 👍

[am11]

@ViktorHofer, any chance this change be backported to 6.0?

[ViktorHofer]

Unfortunately it's too late for 6.0.0 but it's a good candidate for the first servicing release 6.0.1. Might make sense to prep a PR against release/6.0 with the servicing template.

cc @danmoseley