javac 7 is able to generate inner class that can't be verified

[Remi Forax]

ping !

Rémi

On 07/05/2012 01:00 PM, Rémi Forax wrote:
> Hi Maurizio, hi all,
> there is a dubious code in javac that try to reuse existing inner 
> class (or create one)
> when a constructor accessor need to be generated (see 
> Lower.accessConstructorTag).
>
> Used in conjunction with the fact that the inner class exists but
> is created in a block guarded by 'if(false)' leads to a half baked 
> generated class
> (no code for method run()) so the inner-class doesn't pass the 
> verifier check.
>
> Code to reproduce:
> public class EmptyClassWithFakeConstructor {
>   private static class Foo {
>     // need to generate an accessor method
>   }
>
>   public static void main(String[] args) {
>     new Foo();  // call the accessor
>
>     if(false) {
>       new Runnable() {
>         @Override
>         public void run() {   // the code of this method is not generated
>           System.out.println();
>         }
>       }.run();
>     }
>   }
> }
>
> javap -c EmptyClassWithFakeConstructor\$1.class
> Compiled from "EmptyClassWithFakeConstructor.java"
> final class EmptyClassWithFakeConstructor$1 implements 
> java.lang.Runnable {
>   EmptyClassWithFakeConstructor$1();
>
>   public void run();
> }
>
> as you see, the method run is empty (but not abstract).
>
> cheers,
> Rémi
>
>
>