Disable runtime-async for ppc64le, s390x, and Mono runtimes

[shrinivas-sidral]

[ppc64le][s390x][Mono] Disable runtime-async feature on unsupported architectures

Disable runtime-async for ppc64le, s390x, and Mono builds to resolve InvalidProgramException test failures.

Description

ASP.NET Core enables the experimental runtime-async feature (<Features>$(Features);runtime-async=on</Features>) for net11.0 framework and test assemblies.

The Mono runtime and JIT backends for ppc64le and s390x do not support this new async IL format. This causes widespread System.InvalidProgramException: Invalid IL code ... ret failures at runtime (such as in GenericWebHostService:StartAsync), breaking test execution.

Changes

• Defined <UseRuntimeAsync>false</UseRuntimeAsync> in Directory.Build.props when TargetArchitecture is ppc64le or s390x, or when DotNetBuildUseMonoRuntime is true.
• Guarded runtime-async=on in Directory.Build.targets with '$(UseRuntimeAsync)' != 'false' to ensure it is not passed on unsupported targets.

Fixes #68067

Cc: @tmds @omajid

[tmds]

Implicit Defaults: In the .NET 11 SDK, Roslyn's internal default for net11.0 targets is runtime-async=on.

@shrinivas-sidral can you clarify this? Afaik the .NET 11 SDK doesn't default to runtime-async=on. I think if it is on, it is by aspnetcore Directory.Build.targets.

[shrinivas-sidral]

Implicit Defaults: In the .NET 11 SDK, Roslyn's internal default for net11.0 targets is runtime-async=on.

@shrinivas-sidral can you clarify this? Afaik the .NET 11 SDK doesn't default to runtime-async=on. I think if it is on, it is by aspnetcore Directory.Build.targets.

Thanks @tmds for pointing that out. The earlier PR description was incorrect, which led to that confusion—sorry about that!

[tmds]

I think if it is on, it is by aspnetcore Directory.Build.targets.

Assuming the above, then it should never be turned on when DotNetBuildUseMonoRuntime=true:

aspnetcore/Directory.Build.targets

Lines 153 to 162 in 70f2905

	<!-- Enable runtime async for net11.0+ source projects that ship only in the Shared Framework -->
	<PropertyGroup Condition="'$(IsAspNetCoreApp)' == 'true' AND
	'$(IsPackable)' != 'true' AND
	$([MSBuild]::IsTargetFrameworkCompatible('$(TargetFramework)', 'net11.0')) AND
	'$(UseRuntimeAsync)' != 'false' AND
	'$(DotNetBuildUseMonoRuntime)' != 'true' AND
	'$(TargetOS)' != 'browser' AND
	!$(RuntimeIdentifier.StartsWith('browser-'))">
	<Features>$(Features);runtime-async=on</Features>
	</PropertyGroup>

Depending on how you run the build/test you may manually have to add /p:DotNetBuildUseMonoRuntime=true.

The changes in this PR shouldn't be needed.

[shrinivas-sidral]

@dotnet-policy-service agree company="IBM"

[dotnet-policy-service]

Hey @dotnet/aspnet-build, looks like this PR is something you want to take a look at.

[tmds]

@shrinivas-sidral and I are looking into why DotNetBuildUseMonoRuntime=true doesn't seem to be working sometimes. We'll post an update. No need to review until then.