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kotlinlang

Heyho,
I run into a stack overflow with this one. We loop with “Some logic here”. Do you know why?

```fun main() {
    val a = Baz()
    a.remove("test")
}

class Baz : Bar() {
    override fun remove(key: String): Boolean {
        println("Some logic here")
        return super.remove(key)
    }
}

abstract class Bar : Foo<String>()

abstract class Foo<K> : MutableList<K> {
    override fun remove(key: K) : Boolean {
        println("This is never executed")
        return true
    }

    // other MutableList Impls with TODO()
}```

BTW, an actual compilable example:
```fun main() {
    Impl().remove("test")
}

class Impl : Parent() {
    override fun remove(key: String): Boolean {
        println("Some logic here")
        return super.remove(key)
    }
}

abstract class Parent : Grandparent&lt;String&gt;() {
//    override fun remove(key: String): Boolean {
//        return super.remove(key)
//    }
}

abstract class Grandparent&lt;K&gt; : MutableList&lt;K&gt; by mutableListOf() {
    override fun remove(key: K): Boolean {
        println("This is never executed")
        return true
    }
}```

If I uncomment those lines in the middle class, it runs fine.

Having said that, it's almost never the right thing to implement your own MutableList, you might be making your life more difficult.

This also looks like it specifically a problem with MutableList.  If I create a different interface, it also runs fine.

I think it's related to the use of generics. Kotlin generates bridging methods for the generic types, and the bug is in those.

Hmm, I'm not sure its the use of generics, given that a non MutableList class works fine.

Anyway, <@U012GQP1E3B>, hopefully that gives you what you need.

I think this is the bad bytecode, in `Bar`:
```  public final bridge remove(Ljava/lang/Object;)Z
   L0
    LINENUMBER 13 L0
    ALOAD 1
    INSTANCEOF java/lang/String
    IFNE L1
    ICONST_0
    IRETURN
   L1
   FRAME SAME
    ALOAD 0
    ALOAD 1
    CHECKCAST java/lang/String
    INVOKEVIRTUAL Bar.remove (Ljava/lang/String;)Z
    IRETURN
    MAXSTACK = 2
    MAXLOCALS = 2```
`Bar.remove(Object)` is calling `Bar.remove(String)`, which is the one that's actually overridden :grimacing:. It should probably just be calling `Foo.remove(Object)` instead.

Anyway there's nothing that can be done about it other than raising a ticket, or as <@U06474ZDNDC> suggested, just not trying to implement `MutableList` :smile:

This example is more simple than the real world. There we have a store, implementing MutableMap by delegation

Yeah, you will need to use that work around. 

Will do.
I reported it here:
<https://youtrack.jetbrains.com/issue/KT-64458/Super-invokes-itself-leading-to-Stackoverflow-Error>

Thank you folks, for looking into it