[lworld] RFR: 8273301: [lworld] Bootstrap of instance-capturing lambda fails for reference favoring primitive types.

[Srikanth Adayapalam]

On Thu, 2 Sep 2021 20:10:36 GMT, Jesper Steen Møller <jespersm at openjdk.org> wrote:

> Fix the test by adjusting bootstrap parameters, like it was fixed in JDK-8271583.

Looks good to me - However, I would like to ask Mandy whether we are working around a problem in the runtime that should really be fixed there. @mlchung Could you please take a look at the code generated with and without fix and see if the change in javac emitted code is the proper way for this to be fixed ? 

The failure mode is

Caused by: java.lang.invoke.LambdaConversionException: Invalid receiver type primitive X; not a subtype of implementation type primitive X


The failing code being:

public java.util.function.Supplier<X> makeCopier();
    descriptor: ()Ljava/util/function/Supplier;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
         0: aload_0
         1: invokedynamic #7,  0              // InvokeDynamic #0:get:(LX;)Ljava/util/function/Supplier;
         6: areturn
      LineNumberTable:
        line 12: 0
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       7     0  this   QX;


and the patch here alters the generated code to be:

 public java.util.function.Supplier<X> makeCopier();
    descriptor: ()Ljava/util/function/Supplier;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
         0: aload_0
         1: invokedynamic #7,  0              // InvokeDynamic #0:get:(QX;)Ljava/util/function/Supplier;
         6: areturn
      LineNumberTable:
        line 12: 0
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       7     0  this   QX;

-------------

PR: https://git.openjdk.java.net/valhalla/pull/545