Inconsistent InnerClass attribute in delayed init body

[retronym]

⚡ scala
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scala> :paste -raw
// Entering paste mode (ctrl-D to finish)

package p1; object A extends App { println("here") }

// Exiting paste mode, now interpreting.


scala> val cls = Class.forName("p1.A$delayedInit$body")
cls: Class[_] = class p1.A$delayedInit$body

scala> cls.getEnclosingClass
java.lang.IncompatibleClassChangeError: p1.A and p1.A$delayedInit$body disagree on InnerClasses attribute
  at java.lang.Class.getDeclaringClass0(Native Method)
  at java.lang.Class.getDeclaringClass(Class.java:1235)
  at java.lang.Class.getEnclosingClass(Class.java:1277)
  ... 29 elided

[retronym]

The module class A$ has:

SourceFile: "a.scala"
InnerClasses:
     public static final #12= #9 of #11; //delayedInit$body=class p1/A$delayedInit$body of class p1/A
Error: unknown attribute

But there is no corresponding entry in A$delayedInit$body.class nor in A.class

[shelajev]

Hi, we hit a similar issue while trying to compile scala or akka apps to native images with GraalVM.
For example, the akka-quickstart-scala uses the
object Main extends App { main class, and we hit the problem as described in graal#370.

Currently it can be worked around by using the Object + main function syntax as described in graal#384, but it's quite inconvenient that it doesn't work out of the box.

I'm not sure I have the understanding of the scala compiler necessary to try fixing it myself. But if I can provide any additional information I'd be happy to, I'd like to fix this issue. Thank you!

[lrytz]

scala/scala#6788