Re: [Ikvm-developers] Type mapping & interface inheritance question

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OK, so there is another interface between IA & IB, but it should still work.
I've managed to reproduce the problem with simple test interfaces/classes.
It seems to compile when IA,IA2 & IB are implemented in C# and compiled with
mcs, but not when implemented in Java and ikvmc'd.
The mcs error is:
Main.cs(7) error CS1502: The best overloaded match for method 'void F.f 
(IA)' has some invalid arguments
Main.cs(7) error CS1503: Argument 0: Cannot convert from 'C' to 'IA'
Main.cs(7) error CS1501: No overload for method `f' takes `1' arguments
Main.cs(7) error CS8006: Could not find any applicable function for this 
argument list
Compilation failed: 4 error(s), 0 warnings

I'll paste all the C#/Java and monodis output of the IL code
from both mcs & ikvmc for comparison (sorry about the length).
Thanks for taking time to check it out.
-David.

// IA.java:
public interface IA
{
  void methodA();
}

// IA2.java:
public interface IA2 extends IA
{
  void methodA2();
}

// IB.java:
public interface IB extends IA2
{
  void methodB();
}

// F.java:
public class F
{
  public void f(IA a) {}
}

// C.cs:
public class C : IB
{
  public void methodA() {}
  public void methodA2() {}
  public void methodB() {}
}

// Main.cs
public class MainClass
{
  public static void Main()
  {
    F f = new F();
    C c = new C();
    f.f(c);
  }
}

The IA.cs, IA2.cs & IB.cs are just analogues to their .java 
counterparts, I won't
paste them in.

Now, monodis output of AA2BF.dll which was created from a AA2BF.jar 
containing
the .class files output from Sun's javac using ikvmc.

.assembly extern IKVM.GNU.Classpath
{
  .ver 0:9:1713:20439
}
.assembly extern IKVM.Runtime
{
  .ver 0:9:1714:29037
}
.assembly 'AA2BF'
{
  .hash algorithm 0x00008004
  .ver  0:0:0:0
}
.module AA2BF // GUID = {5B662C24-8A4F-4ADE-93E5-0B301484E265}

.custom instance void class 
[IKVM.Runtime]IKVM.Attributes.JavaModuleAttribute::.ctor() =  (01 00 00 
00 ) // ....

  .class interface public auto ansi abstract beforefieldinit IA
  {

    // method line 1
    .method public virtual  abstract
           instance default void methodA ()  cil managed
    {
        // Method begins at RVA 0x0
    } // end of method IA::instance default void methodA ()

  } // end of class IA

  .class interface public auto ansi abstract beforefieldinit IA2
      implements IA  {
    .custom instance void class 
[IKVM.Runtime]IKVM.Attributes.ImplementsAttribute::.ctor(string[]) =  
(01 00 01 00 00 00 02 49 41 00 00 ) // .......IA..

    // method line 2
    .method public virtual  abstract
           instance default void methodA2 ()  cil managed
    {
        // Method begins at RVA 0x0
    } // end of method IA2::instance default void methodA2 ()

  } // end of class IA2

  .class public auto ansi beforefieldinit F
      extends [IKVM.GNU.Classpath]java.lang.Object
  {

    // method line 3
    .method public specialname  rtspecialname
           instance default void .ctor ()  cil managed
    {
        // Method begins at RVA 0x20ec
    // Code size 9 (0x9)
    .maxstack 8
    IL_0000:  ldarg.0
    IL_0001:  call instance void class 
[IKVM.GNU.Classpath]java.lang.Object::.ctor()
    IL_0006:  ret
    IL_0007:  br.s IL_0007

    } // end of method F::instance default void .ctor ()

    // method line 4
    .method public virtual  newslot
           instance default void f (class IA )  cil managed
    {
        // Method begins at RVA 0x20f6
    // Code size 3 (0x3)
    .maxstack 8
    IL_0000:  ret
    IL_0001:  br.s IL_0001

    } // end of method F::instance default void f (class IA )

  } // end of class F

  .class interface public auto ansi abstract beforefieldinit IB
      implements IA2  {
    .custom instance void class 
[IKVM.Runtime]IKVM.Attributes.ImplementsAttribute::.ctor(string[]) =  
(01 00 01 00 00 00 03 49 41 32 00 00 ) // .......IA2..

    // method line 5
    .method public virtual  abstract
           instance default void methodB ()  cil managed
    {
        // Method begins at RVA 0x0
    } // end of method IB::instance default void methodB ()

  } // end of class IB

=======
For comparison, the monodis output of AA2BF.dll generated from the C# 
implementations:

.assembly extern mscorlib
{
  .ver 1:0:5000:0
}
.assembly 'AA2BF'
{
  .hash algorithm 0x00008004
  .ver  0:0:0:0
}
.module AA2BF.dll // GUID = {626E2C5C-24B9-4861-AF8B-A0ACB44A0E25}

  .class interface public auto ansi abstract IA
  {

    // method line 1
    .method public virtual  hidebysig  newslot  abstract
           instance default void methodA ()  cil managed
    {
        // Method begins at RVA 0x0
    } // end of method IA::instance default void methodA ()

  } // end of class IA

  .class interface public auto ansi abstract IA2
      implements IA  {

    // method line 2
    .method public virtual  hidebysig  newslot  abstract
           instance default void methodA2 ()  cil managed
    {
        // Method begins at RVA 0x0
    } // end of method IA2::instance default void methodA2 ()

  } // end of class IA2

  .class interface public auto ansi abstract IB
      implements IA  {

    // method line 3
    .method public virtual  hidebysig  newslot  abstract
           instance default void methodB ()  cil managed
    {
        // Method begins at RVA 0x0
    } // end of method IB::instance default void methodB ()

  } // end of class IB

  .class public auto ansi beforefieldinit F
      extends [mscorlib]System.Object
  {

    // method line 4
    .method public hidebysig  specialname  rtspecialname
           instance default void .ctor ()  cil managed
    {
        // Method begins at RVA 0x20ec
    // Code size 7 (0x7)
    .maxstack 8
    IL_0000:  ldarg.0
    IL_0001:  call instance void valuetype [mscorlib]System.Object::.ctor()
    IL_0006:  ret
    } // end of method F::instance default void .ctor ()

    // method line 5
    .method public hidebysig
           instance default void f (class IA a)  cil managed
    {
    .param [1]
        // Method begins at RVA 0x20f4
    // Code size 1 (0x1)
    .maxstack 8
    IL_0000:  ret
    } // end of method F::instance default void f (class IA a)

  } // end of class F

=====
Here is some IL code from main.exe that was sucessfully compiled from 
the C# implementations.
Q: Why does class C explicitly reference implementing IA & IB, but not IA2?
Also, another anomaly (mcs bug?), if I remove the implementation of 
method 'methodA2()'
from class C, Main still compiles fine (it instantiates a C despite the 
fact that there is no
implementation for IA2.methodA2()!) - or am I missing something here?

.assembly extern mscorlib
{
  .ver 1:0:5000:0
}
.assembly extern AA2BF
{
  .ver 0:0:0:0
}
.assembly 'main'
{
  .hash algorithm 0x00008004
  .ver  0:0:0:0
}
.module main.exe // GUID = {276CAC31-0ECC-40E1-9859-5988D49C3C7E}

 .class public auto ansi beforefieldinit C
        extends [mscorlib]System.Object
        implements [AA2BF]IB, [AA2BF]IA  {

    // method line 1
    .method public hidebysig  specialname  rtspecialname
           instance default void .ctor ()  cil managed
    {
        // Method begins at RVA 0x20ec
        // Code size 7 (0x7)
        .maxstack 8
        IL_0000:  ldarg.0
        IL_0001:  call instance void valuetype 
[mscorlib]System.Object::.ctor()
        IL_0006:  ret
    } // end of method C::instance default void .ctor ()

    // method line 2
    .method public final  virtual  hidebysig  newslot
           instance default void methodA ()  cil managed
    {
        // Method begins at RVA 0x20f4
        // Code size 1 (0x1)
        .maxstack 8
        IL_0000:  ret
    } // end of method C::instance default void methodA ()

    // method line 3
    .method public hidebysig
           instance default void methodA2 ()  cil managed
    {
        // Method begins at RVA 0x20f6
        // Code size 1 (0x1)
        .maxstack 8
        IL_0000:  ret
    } // end of method C::instance default void methodA2 ()

    // method line 4
    .method public final  virtual  hidebysig  newslot
           instance default void methodB ()  cil managed
    {
        // Method begins at RVA 0x20f8
        // Code size 1 (0x1)
        .maxstack 8
        IL_0000:  ret
    } // end of method C::instance default void methodB ()

  } // end of class C

  .class public auto ansi beforefieldinit MainClass
        extends [mscorlib]System.Object
  {

    // method line 5
    .method public hidebysig  specialname  rtspecialname
           instance default void .ctor ()  cil managed
    {
        // Method begins at RVA 0x20fa
        // Code size 7 (0x7)
        .maxstack 8
        IL_0000:  ldarg.0
        IL_0001:  call instance void valuetype 
[mscorlib]System.Object::.ctor()
        IL_0006:  ret
    } // end of method MainClass::instance default void .ctor ()

    // method line 6
    .method public static  hidebysig
           default void Main ()  cil managed
    {
        // Method begins at RVA 0x2102
        .entrypoint
        // Code size 20 (0x14)
        .maxstack 3
        .locals init (
                class [AA2BF]F  V_0,
                class C V_1)
        IL_0000:  newobj instance void class [AA2BF]F::.ctor()
        IL_0005:  stloc.0
        IL_0006:  newobj instance void class C::.ctor()
        IL_000b:  stloc.1
        IL_000c:  ldloc.0
        IL_000d:  ldloc.1
        IL_000e:  callvirt instance void class [AA2BF]F::f(class [AA2BF]IA)
        IL_0013:  ret
    } // end of method MainClass::default void Main ()

  } // end of class MainClass