LambdaMetafactory related issues

[DarkDimius]

object O {
  val x: String => String = a => a
  def main(args: Array[String]): Unit = {
  }
}

Current status: on 802a93b, after fixing invocation type I get

Exception in thread "main" java.lang.BootstrapMethodError: call site initialization exception
    at java.lang.invoke.CallSite.makeSite(CallSite.java:328)
    at java.lang.invoke.MethodHandleNatives.linkCallSite(MethodHandleNatives.java:296)
    at O$.<init>(A.scala:1)
    at O$.<clinit>(A.scala)
    at O.main(A.scala)
Caused by: java.lang.invoke.LambdaConversionException: Incorrect number of parameters for instance method invokeSpecial O$.$anonfun$$init$$1:(String)String; 0 captured parameters, 1 functional interface method parameters, 1 implementation parameters
    at java.lang.invoke.AbstractValidatingLambdaMetafactory.validateMetafactoryArgs(AbstractValidatingLambdaMetafactory.java:193)
    at java.lang.invoke.LambdaMetafactory.metafactory(LambdaMetafactory.java:303)
    at java.lang.invoke.CallSite.makeSite(CallSite.java:289)
    ... 4 more

dark@reco /tmp/t $ javap -p -s -l -verbose O$
Classfile /private/tmp/t/O$.class
  Last modified Apr 10, 2015; size 1188 bytes
  MD5 checksum bb135abd9c605d63ae7638fd35278f89
  Compiled from "A.scala"
public final class O$
  minor version: 0
  major version: 52
  flags: ACC_PUBLIC, ACC_FINAL, ACC_SUPER
Constant pool:
   #1 = Utf8               O$
   #2 = Class              #1             // O$
   #3 = Utf8               java/lang/Object
   #4 = Class              #3             // java/lang/Object
   #5 = Utf8               A.scala
   #6 = Utf8               MODULE$
   #7 = Utf8               LO$;
   #8 = Utf8               x$$local
   #9 = Utf8               Lscala/Function1;
  #10 = Utf8               <clinit>
  #11 = Utf8               ()V
  #12 = Utf8               <init>
  #13 = NameAndType        #12:#11        // "<init>":()V
  #14 = Methodref          #2.#13         // O$."<init>":()V
  #15 = Methodref          #4.#13         // java/lang/Object."<init>":()V
  #16 = NameAndType        #6:#7          // MODULE$:LO$;
  #17 = Fieldref           #2.#16         // O$.MODULE$:LO$;
  #18 = Utf8               java/lang/invoke/LambdaMetafactory
  #19 = Class              #18            // java/lang/invoke/LambdaMetafactory
  #20 = Utf8               metafactory
  #21 = Utf8               (Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodHandle;Ljava/lang/invoke/MethodType;)Ljava/lang/invoke/CallSite;
  #22 = NameAndType        #20:#21        // metafactory:(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodHandle;Ljava/lang/invoke/MethodType;)Ljava/lang/invoke/CallSite;
  #23 = Methodref          #19.#22        // java/lang/invoke/LambdaMetafactory.metafactory:(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodHandle;Ljava/lang/invoke/MethodType;)Ljava/lang/invoke/CallSite;
  #24 = MethodHandle       #6:#23         // invokestatic java/lang/invoke/LambdaMetafactory.metafactory:(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodHandle;Ljava/lang/invoke/MethodType;)Ljava/lang/invoke/CallSite;
  #25 = Utf8               (Ljava/lang/Object;)Ljava/lang/Object;
  #26 = MethodType         #25            //  (Ljava/lang/Object;)Ljava/lang/Object;
  #27 = Utf8               $anonfun$$init$$1
  #28 = Utf8               (Ljava/lang/String;)Ljava/lang/String;
  #29 = NameAndType        #27:#28        // $anonfun$$init$$1:(Ljava/lang/String;)Ljava/lang/String;
  #30 = Methodref          #2.#29         // O$.$anonfun$$init$$1:(Ljava/lang/String;)Ljava/lang/String;
  #31 = MethodHandle       #7:#30         // invokespecial O$.$anonfun$$init$$1:(Ljava/lang/String;)Ljava/lang/String;
  #32 = MethodType         #28            //  (Ljava/lang/String;)Ljava/lang/String;
  #33 = Utf8               apply
  #34 = Utf8               ()Lscala/compat/java8/JFunction1;
  #35 = NameAndType        #33:#34        // apply:()Lscala/compat/java8/JFunction1;
  #36 = InvokeDynamic      #0:#35         // #0:apply:()Lscala/compat/java8/JFunction1;
  #37 = Utf8               this
  #38 = Utf8               x
  #39 = Utf8               ()Lscala/Function1;
  #40 = NameAndType        #8:#9          // x$$local:Lscala/Function1;
  #41 = Fieldref           #2.#40         // O$.x$$local:Lscala/Function1;
  #42 = Utf8               main
  #43 = Utf8               ([Ljava/lang/String;)V
  #44 = Utf8               args
  #45 = Utf8               [Ljava/lang/String;
  #46 = Utf8               a
  #47 = Utf8               Ljava/lang/String;
  #48 = Utf8               Code
  #49 = Utf8               LocalVariableTable
  #50 = Utf8               LineNumberTable
  #51 = Utf8               BootstrapMethods
  #52 = Utf8               SourceFile
  #53 = Utf8               ScalaSig
{
  public static final O$ MODULE$;
    descriptor: LO$;
    flags: ACC_PUBLIC, ACC_STATIC, ACC_FINAL

  private final scala.Function1 x$$local;
    descriptor: Lscala/Function1;
    flags: ACC_PRIVATE, ACC_FINAL

  public static {};
    descriptor: ()V
    flags: ACC_PUBLIC, ACC_STATIC
    Code:
      stack=1, locals=0, args_size=0
         0: new           #2                  // class O$
         3: invokespecial #14                 // Method "<init>":()V
         6: return

  public O$();
    descriptor: ()V
    flags: ACC_PUBLIC
    Code:
      stack=1, locals=2, args_size=1
         0: aload_0
         1: invokespecial #15                 // Method java/lang/Object."<init>":()V
         4: aload_0
         5: putstatic     #17                 // Field MODULE$:LO$;
         8: invokedynamic #36,  0             // InvokeDynamic #0:apply:()Lscala/compat/java8/JFunction1;
        13: astore_1
        14: return
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0      15     0  this   LO$;
      LineNumberTable:
        line 0: 0
        line 1: 8
        line 0: 14

  public scala.Function1 x();
    descriptor: ()Lscala/Function1;
    flags: ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
         0: aload_0
         1: getfield      #41                 // Field x$$local:Lscala/Function1;
         4: areturn
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       5     0  this   LO$;
      LineNumberTable:
        line 1: 0

  public void main(java.lang.String[]);
    descriptor: ([Ljava/lang/String;)V
    flags: ACC_PUBLIC
    Code:
      stack=0, locals=2, args_size=2
         0: return
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       1     0  this   LO$;
            0       1     1  args   [Ljava/lang/String;
      LineNumberTable:
        line 2: 0

  private java.lang.String $anonfun$$init$$1(java.lang.String);
    descriptor: (Ljava/lang/String;)Ljava/lang/String;
    flags: ACC_PRIVATE
    Code:
      stack=1, locals=2, args_size=2
         0: aload_1
         1: areturn
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       2     0  this   LO$;
            0       2     1     a   Ljava/lang/String;
      LineNumberTable:
        line 1: 0
}
BootstrapMethods:
  0: #24 invokestatic java/lang/invoke/LambdaMetafactory.metafactory:(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodHandle;Ljava/lang/invoke/MethodType;)Ljava/lang/invoke/CallSite;
    Method arguments:
      #26 (Ljava/lang/Object;)Ljava/lang/Object;
      #31 invokespecial O$.$anonfun$$init$$1:(Ljava/lang/String;)Ljava/lang/String;
      #32 (Ljava/lang/String;)Ljava/lang/String;
SourceFile: "A.scala"
Error: unknown attribute
  ScalaSig: length = 0x0

[smarter]

It seems that the problem is that $anonfun$$init$$1 is not static.

[DarkDimius]

Currently it shouldn't be static, as 'this' pointer is not added to closure
environment by lambdalift.

But making it static could be beneficial in terms of memory footprint.

On 10 April 2015 14:59:36 Guillaume Martres notifications@github.com wrote:

It seems that the problem is that $anonfun$$init$$1 is not static.

---

Reply to this email directly or view it on GitHub:
#470 (comment)

[DarkDimius]

Invokespecial is used correctly here, as method is private.

I didn't yet had a look at this issue. Ill do it next week.

On 10 April 2015 14:59:36 Guillaume Martres notifications@github.com wrote:

It seems that the problem is that $anonfun$$init$$1 is not static.

---

Reply to this email directly or view it on GitHub:
#470 (comment)

[DarkDimius]

Fixed in lampepfl/scala@09c4a52