.NET 8 Preview 5: Android Release builds no longer work

[jonathanpeppers]

Describe the bug

Likely due to the new default for $(SelfContained): #30038

Any Android Release build fails, because it is trying to not be self-contained:

error XALNS7028: System.IO.FileNotFoundException: Could not load assembly 'mscorlib, Version=2.0.5.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e'. Perhaps it doesn't exist in the Mono for Android profile?

Android Release builds are somewhat unique because they have these settings by default:

• SelfContained=true
• RuntimeIdentifier= (blank)
• RuntimeIdentifiers=android-arm;android-arm64;android-x86;android-x64

macOS/MacCatalyst applications may hit a similar issue, but I haven't heard yet.

To Reproduce

• install the SDK from main/nightly
• dotnet workload install android
• dotnet new android
• dotnet build -c Release

Exceptions (if any)

After setting SelfContained=true by default, it tried to use the host RID:

error NETSDK1082: There was no runtime pack for Microsoft.Android available for the specified RuntimeIdentifier 'osx-x64'.

After setting UseCurrentRuntimeIdentifier=false, it fails with:

error NETSDK1191: A runtime identifier for the property 'SelfContained' couldn't be inferred. Specify a rid explicitly. 

Further technical details

• Started happening here: [main] Update dependencies from dotnet/installer android#8018

This blocks MAUI scenarios for .NET 8 Preview 5.

[jonathanpeppers]

It appears that if I comment out these lines, set SelfContained=true and UseCurrentRuntimeIdentifier=false everything works again:

sdk/src/Tasks/Microsoft.NET.Build.Tasks/targets/Microsoft.NET.RuntimeIdentifierInference.targets

Lines 212 to 214 in cfa8d04

	<NETSdkError Condition="'$(SelfContained)' == 'true' and '$(RuntimeIdentifier)' == ''"
	ResourceName="ImplicitRuntimeIdentifierResolutionForPublishPropertyFailed"
	FormatArguments="SelfContained"/>

[jonathanpeppers]

This may get past this problem, waiting to see CI results:

dotnet/android@6d4dd4e

[jonathanpeppers]

UseCurrentRuntimeIdentifier=false plus passing SelfContained=true to only our "inner build" per RID, solved this problem.