Compiler crash in LambdaLift with local class inside anonymous class capturing local val in superclass argument (AI title)

## Compiler version

Scala 3.8.3

## Minimized code

```scala
class C(a: Any)

def compilerThrows(): Unit =
  val a2 = new Object

  new :
    class S extends C(a2)
    // compiler crashes
    new S{}

// Similar cases that do not crash:
val outsideA = new Object

def noThrow(): Unit =
  val a2 = new Object

  // no crash
  val _ =
    class S extends C(a2)
    new S {}

  new :
    class S extends C(a2)

    // no crash
    class S_outsideA extends C(outsideA)
    new S_outsideA {}

    // no crash
    new C(a2) {}
```

## Output (click arrow to expand)

<details>

```scala
  unhandled exception while running MegaPhase{lambdaLift, elimStaticThis, countOuterAccesses} on .\src\main\scala\compilerThrows.scala

  An unhandled exception was thrown in the compiler.
  Please file a crash report here:
  https://github.com/scala/scala3/issues/new/choose
  For non-enriched exceptions, compile with -Xno-enrich-error-messages.


     while compiling: .\src\main\scala\compilerThrows.scala
        during phase: MegaPhase{lambdaLift, elimStaticThis, countOuterAccesses}
                mode: Mode(ImplicitsEnabled)
     library version: version 3.8.3
    compiler version: version 3.8.3
            settings:

Exception in thread "main" java.lang.IllegalArgumentException: Could not find proxy for val a2: Object in [value a2, 
method compilerThrows, the top-level definitions in package <empty>, package <empty>, package <root>], encl = 
constructor $anon, owners = constructor $anon, anonymous class S {...}, constructor $anon, anonymous class Object 
{...}, method compilerThrows, the top-level definitions in package <empty>, package <empty>, package <root>; 
enclosures = constructor $anon, anonymous class S {...}, package <empty>, package <root>
        at dotty.tools.dotc.transform.LambdaLift$Lifter.searchIn$1(LambdaLift.scala:147)
        at dotty.tools.dotc.transform.LambdaLift$Lifter.proxy(LambdaLift.scala:160)
        at dotty.tools.dotc.transform.LambdaLift$Lifter.proxyRef(LambdaLift.scala:178)
        at dotty.tools.dotc.transform.LambdaLift$Lifter.addFreeArgs$$anonfun$1(LambdaLift.scala:184)
        at scala.collection.immutable.List.map(List.scala:240)
        at dotty.tools.dotc.transform.LambdaLift$Lifter.addFreeArgs(LambdaLift.scala:184)
        at dotty.tools.dotc.transform.LambdaLift.transformApply(LambdaLift.scala:320)
        at dotty.tools.dotc.transform.LambdaLift.transformApply(LambdaLift.scala:319)
        at dotty.tools.dotc.transform.MegaPhase.goApply(MegaPhase.scala:681)
        at dotty.tools.dotc.transform.MegaPhase.transformUnnamed$1(MegaPhase.scala:297)
        at dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:454)
        at dotty.tools.dotc.transform.MegaPhase.loop$2(MegaPhase.scala:471)
        at dotty.tools.dotc.transform.MegaPhase.transformBlock(MegaPhase.scala:476)
        at dotty.tools.dotc.transform.MegaPhase.transformUnnamed$1(MegaPhase.scala:315)
        at dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:454)
        at dotty.tools.dotc.transform.MegaPhase.mapDefDef$1(MegaPhase.scala:265)
        at dotty.tools.dotc.transform.MegaPhase.transformNamed$1(MegaPhase.scala:268)
        at dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:452)
        at dotty.tools.dotc.transform.MegaPhase.transformSpecificTree(MegaPhase.scala:461)
        at dotty.tools.dotc.transform.MegaPhase.transformUnnamed$1(MegaPhase.scala:373)
        at dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:454)
        at dotty.tools.dotc.transform.MegaPhase.transformNamed$1(MegaPhase.scala:272)
        at dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:452)
        at dotty.tools.dotc.transform.MegaPhase.loop$2(MegaPhase.scala:471)
        at dotty.tools.dotc.transform.MegaPhase.transformBlock(MegaPhase.scala:476)
        at dotty.tools.dotc.transform.MegaPhase.transformUnnamed$1(MegaPhase.scala:315)
        at dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:454)
        at dotty.tools.dotc.transform.MegaPhase.loop$2(MegaPhase.scala:471)
        at dotty.tools.dotc.transform.MegaPhase.transformBlock(MegaPhase.scala:476)
        at dotty.tools.dotc.transform.MegaPhase.transformUnnamed$1(MegaPhase.scala:315)
        at dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:454)
        at dotty.tools.dotc.transform.MegaPhase.mapDefDef$1(MegaPhase.scala:265)
        at dotty.tools.dotc.transform.MegaPhase.transformNamed$1(MegaPhase.scala:268)
        at dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:452)
        at dotty.tools.dotc.transform.MegaPhase.transformSpecificTree(MegaPhase.scala:461)
        at dotty.tools.dotc.transform.MegaPhase.transformUnnamed$1(MegaPhase.scala:373)
        at dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:454)
        at dotty.tools.dotc.transform.MegaPhase.transformNamed$1(MegaPhase.scala:272)
        at dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:452)
        at dotty.tools.dotc.transform.MegaPhase.loop$2(MegaPhase.scala:471)
        at dotty.tools.dotc.transform.MegaPhase.transformBlock(MegaPhase.scala:476)
        at dotty.tools.dotc.transform.MegaPhase.transformUnnamed$1(MegaPhase.scala:315)
        at dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:454)
        at dotty.tools.dotc.transform.MegaPhase.loop$2$$anonfun$1(MegaPhase.scala:474)
        at dotty.tools.dotc.transform.MegaPhase.loop$2(MegaPhase.scala:476)
        at dotty.tools.dotc.transform.MegaPhase.transformBlock(MegaPhase.scala:476)
        at dotty.tools.dotc.transform.MegaPhase.transformUnnamed$1(MegaPhase.scala:315)
        at dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:454)
        at dotty.tools.dotc.transform.MegaPhase.mapDefDef$1(MegaPhase.scala:265)
        at dotty.tools.dotc.transform.MegaPhase.transformNamed$1(MegaPhase.scala:268)
        at dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:452)
        at dotty.tools.dotc.transform.MegaPhase.loop$1(MegaPhase.scala:465)
        at dotty.tools.dotc.transform.MegaPhase.transformStats(MegaPhase.scala:465)
        at dotty.tools.dotc.transform.MegaPhase.transformUnnamed$1(MegaPhase.scala:376)
        at dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:454)
        at dotty.tools.dotc.transform.MegaPhase.transformNamed$1(MegaPhase.scala:272)
        at dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:452)
        at dotty.tools.dotc.transform.MegaPhase.loop$1(MegaPhase.scala:465)
        at dotty.tools.dotc.transform.MegaPhase.transformStats(MegaPhase.scala:465)
        at dotty.tools.dotc.transform.MegaPhase.mapPackage$1(MegaPhase.scala:396)
        at dotty.tools.dotc.transform.MegaPhase.transformUnnamed$1(MegaPhase.scala:399)
        at dotty.tools.dotc.transform.MegaPhase.transformTree(MegaPhase.scala:454)
        at dotty.tools.dotc.transform.MegaPhase.transformUnit(MegaPhase.scala:481)
        at dotty.tools.dotc.transform.MegaPhase.run(MegaPhase.scala:493)
        at dotty.tools.dotc.core.Phases$Phase.runOn$$anonfun$1(Phases.scala:406)
        at scala.runtime.function.JProcedure1.apply(JProcedure1.java:15)
        at scala.runtime.function.JProcedure1.apply(JProcedure1.java:10)
        at scala.collection.immutable.List.foreach(List.scala:327)
        at dotty.tools.dotc.core.Phases$Phase.runOn(Phases.scala:399)
        at dotty.tools.dotc.Run.runPhases$1$$anonfun$1(Run.scala:380)
        at scala.runtime.function.JProcedure1.apply(JProcedure1.java:15)
        at scala.runtime.function.JProcedure1.apply(JProcedure1.java:10)
        at scala.collection.ArrayOps$.foreach$extension(ArrayOps.scala:1324)
        at dotty.tools.dotc.Run.runPhases$1(Run.scala:373)
        at dotty.tools.dotc.Run.compileUnits$$anonfun$1$$anonfun$2(Run.scala:420)
        at dotty.tools.dotc.Run.compileUnits$$anonfun$1$$anonfun$adapted$1(Run.scala:420)
        at scala.Function0.apply$mcV$sp(Function0.scala:42)
        at dotty.tools.dotc.Run.showProgress(Run.scala:482)
        at dotty.tools.dotc.Run.compileUnits$$anonfun$1(Run.scala:420)
        at dotty.tools.dotc.Run.compileUnits$$anonfun$adapted$1(Run.scala:432)
        at dotty.tools.dotc.util.Stats$.maybeMonitored(Stats.scala:69)
        at dotty.tools.dotc.Run.compileUnits(Run.scala:432)
        at dotty.tools.dotc.Run.compileSources(Run.scala:319)
        at dotty.tools.dotc.Run.compile(Run.scala:304)
        at dotty.tools.dotc.Driver.doCompile(Driver.scala:37)
        at dotty.tools.dotc.Driver.process(Driver.scala:212)
        at dotty.tools.dotc.Driver.process(Driver.scala:180)
        at dotty.tools.dotc.Driver.process(Driver.scala:192)
        at dotty.tools.dotc.Driver.main(Driver.scala:222)
        at dotty.tools.MainGenericCompiler$.main(MainGenericCompiler.scala:122)
        at dotty.tools.MainGenericCompiler.main(MainGenericCompiler.scala)
        at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
        at java.base/java.lang.reflect.Method.invoke(Method.java:580)
        at coursier.bootstrap.launcher.a.a(Unknown Source)
        at coursier.bootstrap.launcher.Launcher.main(Unknown Source)
```

</details>

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Compiler crash in LambdaLift with local class inside anonymous class capturing local val in superclass argument (AI title) #25943

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Compiler crash in LambdaLift with local class inside anonymous class capturing local val in superclass argument (AI title) #25943

Description

Compiler version

Minimized code

Output (click arrow to expand)

Metadata

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

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