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kotlinlang

This is probably a layer 8 problem, but I'm stumped.  I'm attempting to use kotlinx.serialization without taking a kotlin-reflect dependency in a multiplatform project.  I'm trying to do a basic sanity check in a JVM unit test that this works, but am getting a `NoClassDefFoundError` in `Json.&lt;clinit&gt;`, which is indirectly trying to look up `KPackage`, a kotlin-reflect type.

The test passes if I add a `kotlin-reflect` dependency.  Is it the case that json support requires kotlin-reflect?

stack trace showing the error:

```
kotlin/reflect/KPackage
java.lang.NoClassDefFoundError: kotlin/reflect/KPackage
	at java.lang.Class.forName0(Native Method)
	at java.lang.Class.forName(Class.java:264)
	at kotlin.jvm.internal.Reflection.&lt;clinit&gt;(Reflection.java:26)
	at kotlinx.serialization.json.JsonKt.&lt;clinit&gt;(Json.kt:216)
	at kotlinx.serialization.json.Json.&lt;init&gt;(Json.kt:63)
	at kotlinx.serialization.json.Json.&lt;init&gt;(Json.kt:62)
	at kotlinx.serialization.json.Json.&lt;clinit&gt;(Json.kt:160)
...
```

can you show code or reproduce in a minimal sample,?also sanitycheck versions of kotlin and serialization and plugins ?

Sure.  Kotlin is 1.3.50, serialization is 0.13.0.  I'll paste the snippet in a second.

```
@Serializable
data class BasicData(val eventType: Int)

class SerializationTests {
  @Test
  fun basicTest() {
    Json.stringify(BasicData.serializer(), BasicData(5)) shouldBe """{"eventType":5}"""
  }
}
```

the error happens before `stringify` is ever called - it's raised during class loading of `kotlinx.serialization.json.Json`

I believe this is a bug that is fixed in the next release <https://github.com/Kotlin/kotlinx.serialization/issues/549>

I kind of thought so at first, but the responsible code in `Json.kt` hasn't changed.

i use kotlin 1.3.50 and serialization 0.12.0 and it works fine, not sure why i did not upgrade, but it was one of those bugs

How did you manage to do that? :smile:
`KPackage` has been removed in Kotlin 1.0.1 :open_mouth:
Most likely cause is a rift in the space-time continuum.

Did a really old Kotlin dependency sneak in somehow?