IssueTracker

Thanks to trying out the patch! I was aware that you mentioned that you indicated Android 7.0 - 8.1 in comment#6. What I would like to get some more insights into is if the actual devices are all over the board. E.g. are there any reports from Google Pixel devices. This would help to figure out if the reproduction I have tried to make locally will actually trigger the VerifictionError.

I finally managed to reproduce the VerificationError locally. As the reporter already mentioned this is only a VerificationError on Android 7.0 - 8.1. On all other versions we are testing on the code runs fine.

The reproduction requires a feature split is as follows:

The base contains the following code where Base is captured in a lambda (passed to printInt).

fun printInt(l: () -> Int ) = println(l())

open class Base(@JvmField var x: Int, @JvmField var y: Int)

fun main(args: Array<String>) {
  val base = Base(args.size + 1, args.size + 2)
  printInt { base.x }
  printInt { base.y }
}

And the feature contains this code where Feature extends Base and is a capture in a lambda.

class Feature(x: Int, y: Int) : Base(x, y)

fun feature(i: Int) {
  val f = Feature(i, i + 1)
  printInt { f.x }
  printInt { f.y }
}

When this is compiled the lambdas from the base and the lambdas from the feature are both added to a lambda group which is placed in the base.

The lambda group invoke contains this for the first lambda from the feature:

    8:   0x0d: IgetObject          v0, v2, Field java.lang.Object com.android.tools.r8.kotlin.lambda.b148525512.-$$LambdaGroup$ks$fSoYVxbxeJxmZ1HdRAkuBp7sD8c.$capture$0
    9:   0x0f: CheckCast           v0, com.android.tools.r8.kotlin.lambda.b148525512.Feature
   10:   0x11: Iget                v0, v0, Field int com.android.tools.r8.kotlin.lambda.b148525512.Base.y
         0x13, line 2, locals: [2 -> this]
   11:   0x13: InvokeStatic        { v0 } Ljava/lang/Integer;->valueOf(I)Ljava/lang/Integer;
   12:   0x16: MoveResultObject    v0
   13:   0x17: ReturnObject        v0

Which cause the VerificationError:

java.lang.VerifyError: Verifier rejected class com.android.tools.r8.kotlin.lambda.b148525512.-$$LambdaGroup$ks$fSoYVxbxeJxmZ1HdRAkuBp7sD8c: java.lang.Object com.android.tools.r8.kotlin.lambda.b148525512.-$$LambdaGroup$ks$fSoYVxbxeJxmZ1HdRAkuBp7sD8c.invoke() failed to verify: java.lang.Object com.android.tools.r8.kotlin.lambda.b148525512.-$$LambdaGroup$ks$fSoYVxbxeJxmZ1HdRAkuBp7sD8c.invoke(): [0x11] cannot access instance field int com.android.tools.r8.kotlin.lambda.b148525512.Base.y from object of type Unresolved Reference: com.android.tools.r8.kotlin.lambda.b148525512.Feature (declaration of 'com.android.tools.r8.kotlin.lambda.b148525512.-$$LambdaGroup$ks$fSoYVxbxeJxmZ1HdRAkuBp7sD8c' appears in /tmp/junit8694733721787468186/junit10876155525460741592/out.zip) at com.android.tools.r8.kotlin.lambda.b148525512.BaseKt.main()

If the @JvmField annotation is removed the VerificationError _oes away, as the field access turns into a virtual invoke of the getter.

   17:   0x1c: IgetObject          v0, v2, Field java.lang.Object com.android.tools.r8.kotlin.lambda.b148525512.-$$LambdaGroup$ks$fSoYVxbxeJxmZ1HdRAkuBp7sD8c.$capture$0
   18:   0x1e: CheckCast           v0, com.android.tools.r8.kotlin.lambda.b148525512.Feature
   19:   0x20: InvokeVirtual       { v0 } Lcom/android/tools/r8/kotlin/lambda/b148525512/Base;->getX()I
   20:   0x23: MoveResult          v0
         0x24, line 5, locals: [2 -> this]
   21:   0x24: InvokeStatic        { v0 } Ljava/lang/Integer;->valueOf(I)Ljava/lang/Integer;
   22:   0x27: MoveResultObject    v0
   23:   0x28: ReturnObject        v0

That's Great !!!

Thank you for your time, please if you can, let me know as soon as it will be ready to use.

Thanks for the fix ! I can confirm that the issue is solved with custom R8 that i have tried. But to be sure, you said that it will be fixes in next R8 2.1.x-dev release, so just to be really sure before using it in Production does the latest version 2.1.6-dev contains the fix, or should wait and use the custom version still for the moment ?

OK, it contains it...

Yes, the fix is available in 2.0.30 and 2.1.6-dev.