"java.lang.VerifyError: Bad invoke special instruction" when running a partially applied function implemented in a superclass

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trait TraitOne {
  def m(s: String, i: Int): Int
}

class ClassOne extends TraitOne {
  override def m(s: String, i: Int): Int = i
}

class ClassTwo extends ClassOne {
  val f: (Int) => Int = super[ClassOne].m("two", _)

  def m2(i: Int): Int = f(i)
}

object Demo extends App {
  val v = (new ClassTwo).m2(2)
}

This code compiles without errors, but fails at runtime with this message:

Exception in thread "main" java.lang.VerifyError: Bad invokespecial instruction: current class isn't assignable to reference class.
Exception Details:
  Location:
    ClassTwo$$anonfun$1.apply$mcII$sp(I)I @4: invokespecial
  Reason:
    Error exists in the bytecode
  Bytecode:
    0000000: 2a12 1d1b b700 23ac   

[scabug]

Imported From: https://issues.scala-lang.org/browse/SI-8803?orig=1
Reporter: Egidijus Jankauskas (egis)
Affected Versions: 2.10.4, 2.11.1, 2.11.2

[scabug]

@gourlaysama said:
Nice, that method is very wrong indeed:

public int apply$mcII$sp(int);
    descriptor: (I)I
    flags: ACC_PUBLIC
    Code:
      stack=3, locals=2, args_size=2
         0: aload_0       
         1: ldc           #25                 // String two
         3: iload_1       
         4: invokespecial #31                 // Method ClassOne.m:(Ljava/lang/String;I)I
         7: ireturn       
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       8     0  this   LClassTwo$$anonfun$1;
            0       8     1   x$1   I

this obviously isn't a ClassOne in that anonymous function. It should use the outer reference to the ClassTwo instance. And the outer ref is used when calling super.m or just m, but not super[ClassOne].m...

[scabug]

@lrytz said:
will take a look

[scabug]

@lrytz said:
The issue is specific to closures. Workaround: manually create an accessor.

class ClassTwo extends ClassOne {
  def fBody(s: String, i: Int) = super[ClassOne].m(s, i)
  val f: (Int) => Int = fBody("two", _)
}

Or use -Ydelambdafy:method, which happens to do just that.

[scabug]

@lrytz said:
Actually, it's not specific to closures.

scala/scala#3935