VerifyError when serializing sealed class object on Android 6

[mylesbennett]

Containing app will crash with VerifyError when attempting to serialize a sealed class field using a custom serializer annotated with @Serializer.
I have implemented a workaround based on this almost identical stackoverflow post:
https://stackoverflow.com/questions/50151499/verifyerror-rejecting-class-serializer

This only happens on Android 6.

To Reproduce

@Serializable
sealed class DeviceType(open val name: String) {
    object SetTopBox : DeviceType("settop")
    object Mobile : DeviceType("mobile")
    object Tablet : DeviceType("tablet")

    @Serializer(forClass = DeviceType::class)
    companion object : KSerializer<DeviceType> {
        override fun serialize(encoder: Encoder, obj: DeviceType) {
            encoder.encodeString(obj.name)
        }
    }
}

Resulting crash is:

java.lang.VerifyError: Rejecting class com.producer.data.model.DeviceType$Companion because it failed compile-time verification (declaration of 'com.producer.data.model.DeviceType$Companion' appears in /data/app/com.producer-1/base.apk:classes7.dex)

Expected behavior

Serialization successful - no crash.

Environment

• Kotlin version: 1.3.72
• Library version: 0.20.0
• Kotlin platforms: JVM
• Gradle version: 4.0.1
• IDE version: n/a
• Other relevant context: Android 6.0.1

[kuFEAR]

Hi @sandwwraith , are there any updates on the issue?

[sandwwraith]

I wasn't able to reproduce this on Kotlin 2.x and serialization 1.7.3. If someone still has the project with the reproducer, please post it here.