vtable setup fix for generic default interface methods in mono runtime

[bholmes]

When processing the overrides from interface default methods we should
check if the interface class is a generic type definition first and
inflate with the interface class context.

Test case included.

Fixes #61244

[bholmes]

I am not certain that we need the decl->is_inflated case at all. I can not think of a scenario where this is needed. If we can find the testcase I would like to add that to the tests in this PR as well.

[bholmes]

I did change the code locally to assert if we hit the decl->is_inflated case and override changed. I then ran all the tests and I do think this this assert was hit and I got the same results. Depending on how well dims are covered with our test code, this code block may really be unnecessary.

} else if (decl->is_inflated) {
	MonoMethod *toverride = mono_class_inflate_generic_method_checked (override, mono_method_get_context (decl), error);
	g_assert(toverride == override);
	override = toverride;
	mono_error_assert_ok (error);
}

[lambdageek]

We'll do a separate PR for net7 with

} else if (decl->is_inflated) {
	g_assert_not_reached ();
}

we'll backport the current version to mono/mono and net6

[lambdageek]

/azp run runtime-extra-platforms

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[lambdageek]

/azp run sync-runtime-to-mono

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[MichalStrehovsky]

Before adding new tests, it might be worth checking whether this is already covered by the any of the existing default interface methods tests that are disabled on Mono. There's a ton of them and don't have an issue number:

runtime/src/tests/issues.targets

Lines 1848 to 1850 in 6527b7f

	<ExcludeList Include="$(XunitTestBinBase)/Loader/classloader/DefaultInterfaceMethods/reabstraction/**">
	<Issue>needs triage</Issue>
	</ExcludeList>

runtime/src/tests/issues.targets

Lines 1913 to 1918 in 6527b7f

	<ExcludeList Include="$(XunitTestBinBase)/reflection/DefaultInterfaceMethods/Emit/**">
	<Issue>needs triage</Issue>
	</ExcludeList>
	<ExcludeList Include="$(XunitTestBinBase)/reflection/DefaultInterfaceMethods/InvokeConsumer/**">
	<Issue>needs triage</Issue>
	</ExcludeList>

runtime/src/tests/issues.targets

Lines 1928 to 1930 in 6527b7f

	<ExcludeList Include="$(XunitTestBinBase)/Regressions/coreclr/15241/genericcontext/**">
	<Issue>needs triage</Issue>
	</ExcludeList>

runtime/src/tests/issues.targets

Lines 1934 to 1939 in 6527b7f

	<ExcludeList Include="$(XunitTestBinBase)/Regressions/coreclr/16123/ambiguousconstraint/**">
	<Issue>needs triage</Issue>
	</ExcludeList>
	<ExcludeList Include="$(XunitTestBinBase)/Regressions/coreclr/16355/variance/**">
	<Issue>needs triage</Issue>
	</ExcludeList>

runtime/src/tests/issues.targets

Lines 1943 to 1945 in 6527b7f

	<ExcludeList Include="$(XunitTestBinBase)/Regressions/coreclr/22021/consumer/**">
	<Issue>needs triage</Issue>
	</ExcludeList>

[MichalStrehovsky]

(This test look pretty low value because it doesn't try to do a dispatch or check whether we have a good generic context.)

[bholmes]

I did check and none of the existing tests you list cover this case. If you want a more interesting case I can push the following...

// The .NET Foundation licenses this file to you under the MIT license.

using System;

class Program
{
    static int Main(string[] args)
    {
        return new TestClass().DoTest();
    }
}

public interface OneArgBaseInterface<T1>
{
    int SomeFunc1(T1 someParam1, Type someParam1Type);
}

public interface TwoArgBaseInterface<T1, T2>
{
    int SomeFunc1(T1 someParam1, T2 someParam2, Type someParam1Type, Type someParam2Type);
}

public interface SecondInterface<TParam2Type, TParam1Type> :  OneArgBaseInterface<TParam1Type>, TwoArgBaseInterface<TParam1Type, TParam2Type>
{
    int OneArgBaseInterface<TParam1Type>.SomeFunc1(TParam1Type someParam1, Type someParam1Type)
    {
        if (typeof(TParam1Type) != someParam1Type)
        {
            Console.WriteLine("Failed => 101");
            return 101;
        }

        return 100;
    }

    int TwoArgBaseInterface<TParam1Type, TParam2Type>.SomeFunc1(TParam1Type someParam1, TParam2Type someParam2, Type someParam1Type, Type someParam2Type)
    {
        if (typeof(TParam1Type) != someParam1Type)
        {
            Console.WriteLine("Failed => 102");
            return 102;
        }

        if (typeof(TParam2Type) != someParam2Type)
        {
            Console.WriteLine("Failed => 103");
            return 103;
        }

        return 100;
    }
}

public class TestClass : SecondInterface<int, string>
{
    public int DoTest ()
    {
        int ret = (this as OneArgBaseInterface<string>).SomeFunc1("test string", typeof(string));
        if (ret != 100)
            return ret;

        ret = (this as TwoArgBaseInterface<string, int>).SomeFunc1("test string", 0, typeof(string), typeof(int));
        if (ret != 100)
            return ret;

        Console.WriteLine("Passed => 100");
        return 100;
    }
}

[MichalStrehovsky]

👍 this test looks much more thorough! Thanks!

[bholmes]

@lambdageek pushed a test update. Will need to wait for all the tests to run again.

[lambdageek]

/backport to release/6.0

[github-actions]

Started backporting to release/6.0: https://github.com/dotnet/runtime/actions/runs/1790707501

[lambdageek]

@bholmes Could you merge dotnet/runtime main into this branch. There are some CI infrastructure changes that are preventing the minijit and monointerpreter lanes from running.

[lambdageek]

Thanks @bholmes !