Inlined match crashes when rhs uses private inlined methods

[WojciechMazur]

Regression found in Open Community Build in following projects:

Project	Version	Build URL	Notes
hnaderi/named-codec	0.2.0	Open CB logs	Minimization based on this project
lunatech-labs/course-management-tools	2.0.19	Open CB logs
zio/zio-prelude	1.0.0-RC20 -> 1.0.0-RC21	Open CB logs

Compiler version

3.4.0-RC1-bin-20230921-3d539e6-NIGHTLY
Bisect points to: fe4a685

Minimized code

The usage of inlined method needs to be defined in different compilation unit

// core_0.scala
import scala.deriving.Mirror

trait NamedCodec[A, R]

object NamedCodecPlatform {

  final class Builder[R]() {
    inline def of[T](using m: Mirror.Of[T]): NamedCodec[T, R] =
      inline m match {
        case s: Mirror.SumOf[T]     => sumInst(s)
        case _: Mirror.ProductOf[T] => productInst
      }

    private inline def productInst[T]: NamedCodec[T, R] = ???
    private inline def sumInst[T](m: Mirror.SumOf[T]): NamedCodec[T, R] = ???
  }
}

// test_1.scala
enum Data {
  case A, B, C
}

@main def Test = {
  val builder: NamedCodecPlatform.Builder[Any] = ???
  builder.of[Data]
}

Output (click arrow to expand)

  unhandled exception while running inlining on /Users/wmazur/projects/dotty/bisect/main.test.scala

  An unhandled exception was thrown in the compiler.
  Please file a crash report here:
  https://github.com/lampepfl/dotty/issues/new/choose

     while compiling: /Users/wmazur/projects/dotty/bisect/main.test.scala
        during phase: inlining
                mode: Mode(ImplicitsEnabled)
     library version: version 2.13.10
    compiler version: version 3.4.0-RC1-bin-20230920-b1fc943-NIGHTLY-git-b1fc943
            settings: -classpath /Users/wmazur/Library/Caches/Coursier/v1/https/repo1.maven.org/maven2/org/scala-lang/scala3-library_3/3.4.0-RC1-bin-20230920-b1fc943-NIGHTLY/scala3-library_3-3.4.0-RC1-bin-20230920-b1fc943-NIGHTLY.jar:/Users/wmazur/Library/Caches/Coursier/v1/https/repo1.maven.org/maven2/org/scala-lang/scala-library/2.13.10/scala-library-2.13.10.jar:/Users/wmazur/projects/dotty/bisect/.scala-build/project_7b7a0d617e-28223c4e44/classes/main:/Users/wmazur/projects/dotty/bisect/.scala-build/project_7b7a0d617e-28223c4e44/classes/main -d /Users/wmazur/projects/dotty/bisect/.scala-build/project_7b7a0d617e-28223c4e44/classes/test -java-output-version 17 -sourceroot /Users/wmazur/projects/dotty/bisect

                tree: EmptyTree
       tree position: :<unknown>
           tree type: <notype>
              symbol: val <none>
           call site: package <root> in module class <root>

  == Source file context for tree position ==


Exception in thread "main" java.lang.AssertionError: assertion failed
        at scala.runtime.Scala3RunTime$.assertFailed(Scala3RunTime.scala:11)
        at dotty.tools.dotc.util.Spans$Span$.start$extension(Spans.scala:45)
        at dotty.tools.dotc.ast.Trees$Select.nameSpan(Trees.scala:458)
        at dotty.tools.dotc.inlines.Inliner$InlineTyper.typedSelect(Inliner.scala:774)
        at dotty.tools.dotc.typer.Typer.typedNamed$1(Typer.scala:3080)
        at dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3178)
        at dotty.tools.dotc.typer.ReTyper.typedUnadapted(ReTyper.scala:174)
        at dotty.tools.dotc.inlines.Inliner$InlineTyper.typedUnadapted(Inliner.scala:919)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3258)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3262)
        at dotty.tools.dotc.typer.Typer.typedExpr(Typer.scala:3374)
        at dotty.tools.dotc.typer.Applications.typedTypeApply(Applications.scala:1170)
        at dotty.tools.dotc.typer.Applications.typedTypeApply$(Applications.scala:352)
        at dotty.tools.dotc.inlines.Inliner$InlineTyper.typedTypeApply(Inliner.scala:824)
        at dotty.tools.dotc.typer.Typer.typedUnnamed$1(Typer.scala:3131)
        at dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3179)
        at dotty.tools.dotc.typer.ReTyper.typedUnadapted(ReTyper.scala:174)
        at dotty.tools.dotc.inlines.Inliner$InlineTyper.typedUnadapted(Inliner.scala:919)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3258)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3262)
        at dotty.tools.dotc.typer.Typer.typedExpr(Typer.scala:3374)
        at dotty.tools.dotc.typer.Applications.realApply$1(Applications.scala:958)
        at dotty.tools.dotc.typer.Applications.typedApply(Applications.scala:1118)
        at dotty.tools.dotc.typer.Applications.typedApply$(Applications.scala:352)
        at dotty.tools.dotc.inlines.Inliner$InlineTyper.typedApply(Inliner.scala:820)
        at dotty.tools.dotc.typer.Typer.typedUnnamed$1(Typer.scala:3111)
        at dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3179)
        at dotty.tools.dotc.typer.ReTyper.typedUnadapted(ReTyper.scala:174)
        at dotty.tools.dotc.inlines.Inliner$InlineTyper.typedUnadapted(Inliner.scala:919)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3258)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3262)
        at dotty.tools.dotc.typer.Typer.typedExpr(Typer.scala:3374)
        at dotty.tools.dotc.typer.Typer.typedBlock(Typer.scala:1176)
        at dotty.tools.dotc.typer.Typer.typedUnnamed$1(Typer.scala:3119)
        at dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3179)
        at dotty.tools.dotc.typer.ReTyper.typedUnadapted(ReTyper.scala:174)
        at dotty.tools.dotc.inlines.Inliner$InlineTyper.typedUnadapted(Inliner.scala:919)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3258)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3262)
        at dotty.tools.dotc.typer.Typer.typedExpr(Typer.scala:3374)
        at dotty.tools.dotc.inlines.Inliner$InlineTyper.typedMatchFinish(Inliner.scala:890)
        at dotty.tools.dotc.typer.Typer.typedMatch(Typer.scala:1797)
        at dotty.tools.dotc.inlines.Inliner$InlineTyper.typedMatch(Inliner.scala:851)
        at dotty.tools.dotc.typer.Typer.typedUnnamed$1(Typer.scala:3126)
        at dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3179)
        at dotty.tools.dotc.typer.ReTyper.typedUnadapted(ReTyper.scala:174)
        at dotty.tools.dotc.inlines.Inliner$InlineTyper.typedUnadapted(Inliner.scala:919)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3258)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3262)
        at dotty.tools.dotc.typer.ReTyper.typedTyped(ReTyper.scala:65)
        at dotty.tools.dotc.typer.Typer.typedUnnamed$1(Typer.scala:3116)
        at dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3179)
        at dotty.tools.dotc.typer.ReTyper.typedUnadapted(ReTyper.scala:174)
        at dotty.tools.dotc.inlines.Inliner$InlineTyper.typedUnadapted(Inliner.scala:919)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3258)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3255)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3262)
        at dotty.tools.dotc.inlines.Inliner.inlined(Inliner.scala:681)
        at dotty.tools.dotc.inlines.Inlines$InlineCall.expand(Inlines.scala:449)
        at dotty.tools.dotc.inlines.Inlines$.inlineCall(Inlines.scala:152)
        at dotty.tools.dotc.transform.Inlining$InliningTreeMap.transform(Inlining.scala:95)
        at dotty.tools.dotc.ast.tpd$TreeMapWithPreciseStatContexts.transformBlock$$anonfun$1$$anonfun$1(tpd.scala:1255)
        at dotty.tools.dotc.ast.tpd$TreeMapWithPreciseStatContexts.loop$2(tpd.scala:1237)
        at dotty.tools.dotc.ast.tpd$TreeMapWithPreciseStatContexts.transformStats(tpd.scala:1250)
        at dotty.tools.dotc.ast.tpd$TreeMapWithPreciseStatContexts.transformBlock(tpd.scala:1255)
        at dotty.tools.dotc.ast.Trees$Instance$TreeMap.transform(Trees.scala:1543)
        at dotty.tools.dotc.ast.TreeMapWithImplicits.transform(TreeMapWithImplicits.scala:43)
        at dotty.tools.dotc.transform.Inlining$InliningTreeMap.transform(Inlining.scala:91)
        at dotty.tools.dotc.ast.TreeMapWithImplicits.transform(TreeMapWithImplicits.scala:50)
        at dotty.tools.dotc.transform.Inlining$InliningTreeMap.transform(Inlining.scala:89)
        at dotty.tools.dotc.ast.tpd$TreeMapWithPreciseStatContexts.loop$2(tpd.scala:1250)
        at dotty.tools.dotc.ast.tpd$TreeMapWithPreciseStatContexts.transformStats(tpd.scala:1250)
        at dotty.tools.dotc.ast.tpd$TreeMapWithPreciseStatContexts.transformStats(tpd.scala:1252)
        at dotty.tools.dotc.ast.TreeMapWithImplicits.transform(TreeMapWithImplicits.scala:58)
        at dotty.tools.dotc.transform.Inlining$InliningTreeMap.transform(Inlining.scala:108)
        at dotty.tools.dotc.ast.Trees$Instance$TreeMap.transform(Trees.scala:1597)
        at dotty.tools.dotc.ast.TreeMapWithImplicits.transform(TreeMapWithImplicits.scala:67)
        at dotty.tools.dotc.transform.Inlining$InliningTreeMap.transform(Inlining.scala:89)
        at dotty.tools.dotc.ast.tpd$TreeMapWithPreciseStatContexts.loop$2(tpd.scala:1250)
        at dotty.tools.dotc.ast.tpd$TreeMapWithPreciseStatContexts.transformStats(tpd.scala:1250)
        at dotty.tools.dotc.ast.tpd$TreeMapWithPreciseStatContexts.transformStats(tpd.scala:1252)
        at dotty.tools.dotc.ast.Trees$Instance$TreeMap.transform(Trees.scala:1608)
        at dotty.tools.dotc.ast.TreeMapWithImplicits.transform(TreeMapWithImplicits.scala:67)
        at dotty.tools.dotc.transform.Inlining$InliningTreeMap.transform(Inlining.scala:97)
        at dotty.tools.dotc.transform.Inlining$$anon$2.transform(Inlining.scala:58)
        at dotty.tools.dotc.transform.MacroTransform.run(MacroTransform.scala:18)
        at dotty.tools.dotc.transform.Inlining.run(Inlining.scala:34)
        at dotty.tools.dotc.core.Phases$Phase.runOn$$anonfun$1(Phases.scala:327)
        at scala.collection.immutable.List.map(List.scala:246)
        at dotty.tools.dotc.core.Phases$Phase.runOn(Phases.scala:331)
        at dotty.tools.dotc.transform.Inlining.runOn(Inlining.scala:38)
        at dotty.tools.dotc.Run.runPhases$1$$anonfun$1(Run.scala:246)
        at scala.runtime.function.JProcedure1.apply(JProcedure1.java:15)
        at scala.runtime.function.JProcedure1.apply(JProcedure1.java:10)
        at scala.collection.ArrayOps$.foreach$extension(ArrayOps.scala:1321)
        at dotty.tools.dotc.Run.runPhases$1(Run.scala:263)
        at dotty.tools.dotc.Run.compileUnits$$anonfun$1(Run.scala:271)
        at dotty.tools.dotc.Run.compileUnits$$anonfun$adapted$1(Run.scala:280)
        at dotty.tools.dotc.util.Stats$.maybeMonitored(Stats.scala:71)
        at dotty.tools.dotc.Run.compileUnits(Run.scala:280)
        at dotty.tools.dotc.Run.compileSources(Run.scala:194)
        at dotty.tools.dotc.Run.compile(Run.scala:179)
        at dotty.tools.dotc.Driver.doCompile(Driver.scala:37)
        at dotty.tools.dotc.Driver.process(Driver.scala:197)
        at dotty.tools.dotc.Driver.process(Driver.scala:165)
        at dotty.tools.dotc.Driver.process(Driver.scala:177)
        at dotty.tools.dotc.Driver.main(Driver.scala:207)
        at dotty.tools.dotc.Main.main(Main.scala)
        ```
</details>