IncompatibleClassChangeError: SomeClass and SomeClass$$$$anon$$1 disagree on InnerClasses attribute

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Compiling and running the attached Scala source (short) yields to this runtime exception,

java.lang.IncompatibleClassChangeError: SimpleName and SimpleName$$$$anon$$1 disagree on InnerClasses attribute
at java.lang.Class.getDeclaringClass(Native Method)
at java.lang.Class.getEnclosingClass(Class.java:1081)
at java.lang.Class.getSimpleBinaryName(Class.java:1216)
at java.lang.Class.getSimpleName(Class.java:1108)
at Foo.toString(SimpleName.scala:3)
at java.lang.String.valueOf(String.java:2615)
at java.io.PrintStream.print(PrintStream.java:616)
at java.io.PrintStream.println(PrintStream.java:753)
at scala.Console$$.println(Console.scala:162)
at scala.Predef$$.println(Predef.scala:156)
at SimpleName$$.(SimpleName.scala:13)
at SimpleName$$.(SimpleName.scala)
at SimpleName.main(SimpleName.scala)

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Imported From: https://issues.scala-lang.org/browse/SI-1167?orig=1
Reporter: @aboisvert
Attachments:

• SimpleName.scala (created on Aug 3, 2008 5:29:21 PM UTC, 278 bytes)

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@aboisvert said:
SimpleName.scala

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Geoffrey Alan Washburn (washburn) said:
I can reproduce this with

class Foo {
  override def toString = getClass.getSimpleName
}

object SimpleName extends Application {
  val foo = new Foo {}
  println(foo)
}

Changing the one line to

  override def toString = classOf[Foo].getSimpleName

Makes the problem go away.

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@jrudolph said:
This was supposedly fixed by r15927. But since the commented code was resurrected in r16328 this bug is reappearing.

Here's a simple example:

trait Test {
 def testFunc(i:Int) = ((i:Int) => i + 5)(i)
}

And here the console session:

Welcome to Scala version 2.7.4.final (OpenJDK 64-Bit Server VM, Java 1.6.0_0).
Type in expressions to have them evaluated.
Type :help for more information.

scala> Class.forName("Test$$$$anonfun$$testFunc$$1")
res0: java.lang.Class[_] = class Test$$$$anonfun$$testFunc$$1

scala> res0.getSimpleName
java.lang.IncompatibleClassChangeError: Test and
Test$$$$anonfun$$testFunc$$1 disagree on InnerClasses attribute
       at java.lang.Class.getDeclaringClass(Native Method)
       at java.lang.Class.getEnclosingClass(Class.java:1102)
       at java.lang.Class.getSimpleBinaryName(Class.java:1237)
       at java.lang.Class.getSimpleName(Class.java:1129)
       at .<init>(<console>:6)
       at .<clinit>(<console>)
       at RequestR...

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@paulp said:
Replying to [comment:4 jrudolph]:

This was supposedly fixed by r15927. But since the commented code was resurrected in r16328 this bug is reappearing.

See also #2083, which to my frustration was closed wontfix. (It also arose in the course of what I think should be safe reflection calls.)

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@jrudolph said:
Replying to [comment:5 extempore]:

See also #2083, which to my frustration was closed wontfix. (It also arose in the course of what I think should be safe reflection calls.)
IMO the general restriction to forbid any types with '$$' in the Scala syntax is reasonable (although, failing with only an assertion isn't). What you experienced here, can only happen to you, because you - as a developer of the interpreter - are the only one who has access to the mighty "eval". And it's only then, that implementation details of the compiler output can feed back into the compiler, isn't it?

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Matt Hellige (hellige) said:
Same problem:

java.lang.IncompatibleClassChangeError: scala.collection.Map and scala.collection.Map$$$$anon$$5 disagree on InnerClasses attribute
	at java.lang.Class.getDeclaringClass(Native Method)
	at java.lang.Class.getEnclosingClass(Class.java:1085)
        [...]

I'm using Google's gson JSON library. AFAICS it's just doing very basic reflection... I might be able to find a workaround, but this problem is pretty serious.

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luxspes said:
I am getting this error if I use a code like this (concatente the contents of a list in a comma separated string) inside a method in my class:

val classNames = Conversions.convertList(names).reduceLeft[String] { (acc, n) =>
        acc + ", " + n
        }	

Apparently this makes the compiler generate an incompatible inner class:

java.lang.IncompatibleClassChangeError: com.googlecode.solder.dwr.WeldContainer and com.googlecode.solder.dwr.WeldContainer$$$$anonfun$$getClasses$$1 disagree on InnerClasses attribute
	at java.lang.Class.getDeclaringClass(Native Method)
	at java.lang.Class.getEnclosingClass(Class.java:1085)
	at java.lang.Class.getSimpleBinaryName(Class.java:1220)
	at java.lang.Class.getSimpleName(Class.java:1112)
	at org.jboss.weld.util.Names.typeToString(Names.java:251)
	at org.jboss.weld.util.Names.classToString(Names.java:263)
	at org.jboss.weld.introspector.jlr.WeldClassImpl.<init>(WeldClassImpl.java:151)
	at org.jboss.weld.introspector.jlr.WeldClassImpl.of(WeldClassImpl.java:133)
	at org.jboss.weld.resources.ClassTransformer$$2.call(ClassTransformer.java:72)
	at org.jboss.weld.resources.ClassTransformer$$2.call(ClassTransformer.java:68)
	at java.util.concurrent.FutureTask$$Sync.innerRun(FutureTask.java:303)
	at java.util.concurrent.FutureTask.run(FutureTask.java:138)
	at org.jboss.weld.util.collections.ConcurrentCache.putIfAbsent(ConcurrentCache.java:125)
	at org.jboss.weld.resources.ClassTransformer.loadClass(ClassTransformer.java:67)
	at org.jboss.weld.bootstrap.BeanDeployer.addClass(BeanDeployer.java:59)
	at org.jboss.weld.bootstrap.BeanDeployer.addClasses(BeanDeployer.java:86)
	at org.jboss.weld.bootstrap.BeanDeployment.deployBeans(BeanDeployment.java:134)
	at org.jboss.weld.bootstrap.WeldBootstrap.deployBeans(WeldBootstrap.java:367)
	at org.jboss.weld.environment.servlet.Listener.contextInitialized(Listener.java:158)
	at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:3843)
	at org.apache.catalina.core.StandardContext.start(StandardContext.java:4342)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
	at org.apache.catalina.core.StandardHost.start(StandardHost.java:719)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
	at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
	at org.apache.catalina.core.StandardService.start(StandardService.java:516)
	at org.apache.catalina.core.StandardServer.start(StandardServer.java:710)
	at org.apache.catalina.startup.Catalina.start(Catalina.java:578)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:288)
	at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:413)

I guess this means Weld (JSR-299) and Scala are not compatible. Please fix this!

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Seto (seto) said:
No planning about fixing it?
I'm using it with Weld too. I met this error as well.

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@odersky said:
See also:

http://luxspes.blogspot.com/2009/11/scala-is-not-mature-enough-for-weld.html

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@dragos said:
Hm, can someone please post a reproducible, self-contain test case? I could not reproduce it with any of the examples in the comments, nor the initial program. It's ok if I need some 3rd party library, but please post a program that compiles (nobody here ever used Weld, so I can't come up with something 'basic' any time soon).

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@jrudolph said:
I posted some pretty full disclosure about my findings in comment:4. The problem was fixed the first time in r15927, when two lines were commented out. In r16328 the lines were resurrected. Perhaps you can remember why you've done that?

You may want to look into the [http://old.nabble.com/Re%3A-Scala-Interpreter-Oddity----General-Class-Name-Curio-p25869373.html mailing-list post] which contains more information.

And here, again my example:

Put that into test.scala:

trait Test {
 def testFunc(i:Int) = ((i:Int) => i + 5)(i)
}

Then, do:

% ~/downloads/sources/scala-2.8.0.r19722-b20091119020248/bin/scalac test.scala
% ~/downloads/sources/scala-2.8.0.r19722-b20091119020248/bin/scala -e 'Class.forName("Test$$$$anonfun$$testFunc$$1").getSimpleName'
java.lang.IncompatibleClassChangeError: Test and Test$$$$anonfun$$testFunc$$1 disagree on InnerClasses attribute
	at java.lang.Class.getDeclaringClass(Native Method)
	at java.lang.Class.getEnclosingClass(Class.java:1102)
	at java.lang.Class.getSimpleBinaryName(Class.java:1237)
	at java.lang.Class.getSimpleName(Class.java:1129)
	at Main$$$$anon$$1.<init>((virtual file):6)
	at Main$$.main((virtual file):5)
	at Main.main((virtual file))
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:616)
	at scala.tools.nsc.util.ScalaClassLoader$$$$anonfun$$run$$1.apply(ScalaClassLoader.scala:55)
	at scala.tools.nsc.util.ScalaClassLoader$$class.asContext(ScalaClassLoader.scala:22)
	at scala.tools.nsc.util.ScalaClassLoader$$URLClassLoader.asContext(ScalaClassLoader.scala:61)
	at scala.tools.nsc.util.ScalaClassLoader$$class.run(ScalaClassLoader.scala:55)
	at scala.tools.nsc.util.ScalaClassLoader$$URLClassLoader.run(ScalaClassLoader.scala:61)
	at scala.tools.nsc.ScriptRunner$$.scala$$tools$$nsc$$ScriptRunner$$$$runCompiled(ScriptRunner.scala:326)
	at scala.tools.nsc.ScriptRunner$$$$anonfun$$runCommand$$1.apply(ScriptRunner.scala:371)
	at scala.tools.nsc.ScriptRunner$$$$anonfun$$runCommand$$1.apply(ScriptRunner.scala:371)
	at scala.tools.nsc.ScriptRunner$$$$anonfun$$withCompiledScript$$1.apply(ScriptRunner.scala:298)
	at scala.tools.nsc.ScriptRunner$$$$anonfun$$withCompiledScript$$1.apply(ScriptRunner.scala:298)
	at scala.Option.map(Option.scala:74)
	at scala.tools.nsc.ScriptRunner$$.withCompiledScript(ScriptRunner.scala:298)
	at scala.tools.nsc.ScriptRunner$$.runCommand(ScriptRunner.scala:371)
	at scala.tools.nsc.MainGenericRunner$$.main(MainGenericRunner.scala:140)
	at scala.tools.nsc.MainGenericRunner.main(MainGenericRunner.scala)

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@dragos said:
(In r19895) Fixed #1167.

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@dragos said:
Sorry, I didn't follow the whole interpreter session, I stopped at forName. Anyway, that one is fixed, let's hope it's the same bug the Weld guys are hitting.

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@jsuereth said:
Note, you can reproduce this bug in JAVA by changing source and target versions.

Using the following JDK:

java version "1.6.0_22"
OpenJDK Runtime Environment (IcedTea6 1.10.2) (6b22-1.10.2-0ubuntu1~11.04.1)
OpenJDK 64-Bit Server VM (build 20.0-b11, mixed mode)

I was able to induce this error with a simple static final Nested class with both -source and -target set to 1.5. Looks like we're not alone in the insanity.