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Kotlin to WASM - by lazy init does not work

See original GitHub issue

Another Kotlin oddity, but I have managed to track the exception down to the following by lazy. I am using the shadowJar, so I would have expected the Kotlin stdlib to be included, although this seems to be something reflection based from standard Java…

Here is the command line I am using:

java -jar bytecoder-cli-2019-06-13-executable.jar -classpath=./build/libs/art-trimmed-all.jar -mainclass=art.EntryKotlin -builddirectory=build -backend=wasm -minify=false -optimizationlevel=ALL -filenameprefix=main -maximumwasmpages=1024

and the code that generates the exception below.

class EntryKotlin {
    val me: String by lazy {
        "Hola"
    }

    init {
        println("new entry kotlin")
        //val nada = Class.forName("")
        Main()
    }

    companion object {
        @JvmStatic
        fun main(args: Array<String>?) {
            EntryKotlin()
        }
    }
}

Exception in thread "main" java.lang.reflect.InvocationTargetException
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:48)
        at org.springframework.boot.loader.Launcher.launch(Launcher.java:87)
        at org.springframework.boot.loader.Launcher.launch(Launcher.java:50)
        at org.springframework.boot.loader.JarLauncher.main(JarLauncher.java:51)
Caused by: java.lang.RuntimeException: Error linking class art.EntryKotlin
        at de.mirkosertic.bytecoder.core.BytecodeLinkerContext.resolveClass(BytecodeLinkerContext.java:111)
        at de.mirkosertic.bytecoder.backend.CompileTarget.compile(CompileTarget.java:81)
        at de.mirkosertic.bytecoder.cli.BytecoderCLI.main(BytecoderCLI.java:111)
        ... 8 more
Caused by: java.lang.RuntimeException: Error linking class kotlin.jvm.internal.Reflection
        at de.mirkosertic.bytecoder.core.BytecodeLinkerContext.resolveClass(BytecodeLinkerContext.java:111)
        at de.mirkosertic.bytecoder.core.BytecodeInstructionINVOKESTATIC.performLinking(BytecodeInstructionINVOKESTATIC.java:33)
        at de.mirkosertic.bytecoder.core.BytecodeLinkedClass.resolveMethodSignatureAndBody(BytecodeLinkedClass.java:400)
        at de.mirkosertic.bytecoder.core.BytecodeLinkedClass.resolveStaticMethod(BytecodeLinkedClass.java:370)
        at de.mirkosertic.bytecoder.core.BytecodeLinkedClass.resolveClassInitializer(BytecodeLinkedClass.java:148)
        at de.mirkosertic.bytecoder.core.BytecodeLinkerContext.resolveClass(BytecodeLinkerContext.java:98)
        ... 10 more
Caused by: java.lang.IllegalStateException: Cannot find static method forName in java/lang/Class with signature java.lang.Class(java.lang.String)
        at de.mirkosertic.bytecoder.core.BytecodeInstructionINVOKESTATIC.performLinking(BytecodeInstructionINVOKESTATIC.java:35)
        at de.mirkosertic.bytecoder.core.BytecodeLinkedClass.resolveMethodSignatureAndBody(BytecodeLinkedClass.java:400)
        at de.mirkosertic.bytecoder.core.BytecodeLinkedClass.resolveStaticMethod(BytecodeLinkedClass.java:370)
        at de.mirkosertic.bytecoder.core.BytecodeLinkedClass.resolveClassInitializer(BytecodeLinkedClass.java:148)
        at de.mirkosertic.bytecoder.core.BytecodeLinkerContext.resolveClass(BytecodeLinkerContext.java:98)
        ... 15 more

Issue Analytics

State:
Created 4 years ago
Comments:19 (7 by maintainers)

Top GitHub Comments

1reaction

WhiteHexagoncommented, Apr 3, 2020

more good news, the by lazy is now working 😃 thanks!

btw the .wasm file has jumped by 560KB to 720KB , but maybe that is the GC stuff for the new version? Anyway tomorrow I try the new llvm target.

0reactions

WhiteHexagoncommented, Apr 23, 2020

I missed the notification about this, but that is great news! I shall get back to testing it then 😃

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