Marshal.GetComInterfaceForObject in NativeAOT

[tfenise]

runtime/src/coreclr/nativeaot/System.Private.CoreLib/src/System/Runtime/InteropServices/Marshal.Com.cs

Lines 76 to 97 in 248d6f4

	[SupportedOSPlatform("windows")]
	[EditorBrowsable(EditorBrowsableState.Never)]
	public static IntPtr GetComInterfaceForObject(object o, Type T)
	{
	ArgumentNullException.ThrowIfNull(o);
	ArgumentNullException.ThrowIfNull(T);
	return ComWrappers.ComInterfaceForObject(o, T.GUID);
	}
	[SupportedOSPlatform("windows")]
	[EditorBrowsable(EditorBrowsableState.Never)]
	public static IntPtr GetComInterfaceForObject(object o, Type T, CustomQueryInterfaceMode mode)
	{
	throw new NotSupportedException(SR.PlatformNotSupported_ComInterop);
	}
	[SupportedOSPlatform("windows")]
	public static IntPtr GetComInterfaceForObject<T, TInterface>([DisallowNull] T o)
	{
	return GetComInterfaceForObject(o!, typeof(T));
	}

Line 96 should use typeof(TInterface) instead of typeof(T). Compare to

runtime/src/coreclr/System.Private.CoreLib/src/System/Runtime/InteropServices/Marshal.CoreCLR.cs

Lines 461 to 463 in b40903f

	[SupportedOSPlatform("windows")]
	public static IntPtr GetComInterfaceForObject<T, TInterface>([DisallowNull] T o)
	=> GetComInterfaceForObject(o!, typeof(TInterface), CustomQueryInterfaceMode.Allow);

In addition, it seems inconsistent that in the NativeAOT version, GetComInterfaceForObject(object o, Type T, CustomQueryInterfaceMode mode) throws unconditionally, but GetComInterfaceForObject(object o, Type T) may still work (with the help of ComWrappers.RegisterForMarshalling).

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[agocke]

@MichalStrehovsky and @jkoritzinsky for thoughts

[MichalStrehovsky]

@MichalStrehovsky and @jkoritzinsky for thoughts

The fix seems simple enough, but we should probably have a test. This seems to indicate there is a test hole for these APIs with built-in COM interop disabled (i.e. how do we know the code works as-is on CoreCLR-JIT?).