GetFunctionPointerForDelegateTests tests fail with Specified cast is not valid on Browser

[mdh1418]

When running System.Runtime.InteropServices library tests on Browser wasm, two functions fail with Specified cast is not valid:

• GetFunctionPointerForDelegate_MarshalledDelegateNonGeneric_ReturnsExpected
• GetFunctionPointerForDelegate_MarshalledDelegateGeneric_ReturnsExpected

Note

When the tests are not ordered, the suite sometimes fails with the two tests above

[FAIL] System.Runtime.InteropServices.Tests.GetFunctionPointerForDelegateTests.GetFunctionPointerForDelegate_MarshalledDelegateNonGeneric_ReturnsExpected
System.InvalidCastException : Specified cast is not valid.
at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
[FAIL] System.Runtime.InteropServices.Tests.GetFunctionPointerForDelegateTests.GetFunctionPointerForDelegate_MarshalledDelegateGeneric_ReturnsExpected
System.InvalidCastException : Specified cast is not valid.
at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)

And other times, it fails with the six tests from GetDelegateForFunctionPointerTests.cs

[FAIL] System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests.GetDelegateForFunctionPointer_NonGeneric_ReturnsExpected(t: typeof(System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests+NonGenericDelegate))
Assert.IsType() Failure
Expected: System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests+NonGenericDelegate
Actual: System.Runtime.InteropServices.Tests.GetFunctionPointerForDelegateTests+NonGenericDelegate
 at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
[FAIL] System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests.GetDelegateForFunctionPointer_NonGeneric_ReturnsExpected(t: typeof(System.MulticastDelegate))
Assert.IsType() Failure
Expected: System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests+NonGenericDelegate
Actual: System.Runtime.InteropServices.Tests.GetFunctionPointerForDelegateTests+NonGenericDelegate
 at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
[FAIL] System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests.GetDelegateForFunctionPointer_NonGeneric_ReturnsExpected(t: typeof(System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests+OtherNonGenericDelegate))
Assert.IsType() Failure
Expected: System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests+NonGenericDelegate
Actual: System.Runtime.InteropServices.Tests.GetFunctionPointerForDelegateTests+NonGenericDelegate
 at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
[FAIL] System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests.GetDelegateForFunctionPointer_GenericInvalidType_ReturnsExpected
Assert.IsType() Failure
Expected: System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests+NonGenericDelegate
Actual: System.Runtime.InteropServices.Tests.GetFunctionPointerForDelegateTests+NonGenericDelegate
 at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
[FAIL] System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests.GetDelegateForFunctionPointer_CollectibleType_ReturnsExpected
Assert.IsType() Failure
Expected: System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests+NonGenericDelegate
Actual: System.Runtime.InteropServices.Tests.GetFunctionPointerForDelegateTests+NonGenericDelegate
 at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
[FAIL] System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests.GetDelegateForFunctionPointer_Generic_ReturnsExpected
System.InvalidCastException : Specified cast is not valid.
 at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture) 

[ghost]

Tagging subscribers to this area: @BrzVlad, @lewurm
Notify danmosemsft if you want to be subscribed.

[vargaz]

These now fail with:
System.PlatformNotSupportedException : No native to managed transitions on this platform.
They cannot be supported without the pinvoke generator.

[lewing]

@vargaz this sounds like net6?

[vargaz]

Probably.

[pavelsavara]

I will remove the [ActiveIssue] from System.Net.Http.Functional.Tests in my PR #54289 because it works there.

[pavelsavara]

This was probably fixed already. The remaining [ActiveIssue] are in src\libraries\System.Runtime.InteropServices\tests\System\Runtime\InteropServices\Marshal\GetFunctionPointerForDelegateTests.cs but that is in assembly which is not targeting Browser right now.

@mdh1418 how did you made them run on browser before ?

[vargaz]

This PR:
#56883
will fix the error handling, so it will now fail with a more reasonable error message.

[SamMonoRT]

@lewing - is this a must for 6.0 ?

[SamMonoRT]

Moving to 7.0

[ilonatommy]

@vargaz, are we able to solve it in 7.0?

[lewing]

@ilonatommy can you check if these tests still fail?

[ilonatommy]

The error message changed to:

[FAIL] System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests.GetDelegateForFunctionPointer_CantCast_ThrowsInvalidCastException
   System.PlatformNotSupportedException : No native to managed transition for method 'void System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests:Method (string)', missing [UnmanagedCallersOnly] attribute.
  at System.Runtime.InteropServices.Marshal.GetFunctionPointerForDelegate(Delegate d)
  at System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests.GetDelegateForFunctionPointer_CantCast_ThrowsInvalidCastException()
  at System.Reflection.MethodInvoker.InterpretedInvoke(Object obj, IntPtr* args)
  at System.Reflection.MethodInvoker.Invoke(Object obj, IntPtr* args, BindingFlags invokeAttr)

When we use the hint and add the decorator:

        [UnmanagedCallersOnly]
        private static void Method(string s) { }

GetFunctionPointerForDelegateTests.cs(124,36): error CS8894: Cannot use 'string' as a parameter type on a method attributed with 'UnmanagedCallersOnly'

When we change the method to receive char* in unsafe context, the message is back to missing [UnmanagedCallersOnly], so apparently I am not using it correctly.

I am not sure how to fix this.

Tests failing with this message:

[FAIL] System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests.GetDelegateForFunctionPointer_CantCast_ThrowsInvalidCastException
[FAIL] System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests.GetDelegateForFunctionPointer_GenericInvalidType_ReturnsExpected
[FAIL] System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests.GetDelegateForFunctionPointer_NonGeneric_ReturnsExpected(t: typeof(System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests+NonGenericDelegate))
[FAIL] System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests.GetDelegateForFunctionPointer_NonGeneric_ReturnsExpected(t: typeof(System.MulticastDelegate))
[FAIL] System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests.GetDelegateForFunctionPointer_NonGeneric_ReturnsExpected(t: typeof(System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests+OtherNonGenericDelegate))
[FAIL] System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests.GetDelegateForFunctionPointer_Generic_ReturnsExpected
[FAIL] System.Runtime.InteropServices.Tests.GetDelegateForFunctionPointerTests.GetDelegateForFunctionPointer_CollectibleType_ReturnsExpected
[FAIL] System.Runtime.InteropServices.Tests.GetFunctionPointerForDelegateTests.GetFunctionPointerForDelegate_MarshalledDelegateGeneric_ReturnsExpected
[FAIL] System.Runtime.InteropServices.Tests.GetFunctionPointerForDelegateTests.GetFunctionPointerForDelegate_NormalDelegateGeneric_ReturnsExpected
[FAIL] System.Runtime.InteropServices.Tests.GetFunctionPointerForDelegateTests.GetFunctionPointerForDelegate_MarshalledDelegateNonGeneric_ReturnsExpected
[FAIL] System.Runtime.InteropServices.Tests.GetFunctionPointerForDelegateTests.GetFunctionPointerForDelegate_NormalDelegateNonGeneric_ReturnsExpected

[lewing]

@vargaz is this something we expect to work?

[lewing]

cc @kg @BrzVlad