Implicit resolution search crashes when dealing with inferred path dependent context function types when inference involves higher kinded types and implicit cannot be found

## Compiler version

3.8.2

## Minimized code



```Scala
trait A[B[_]]:
  type C
  
def apply[D[_]](other: (a: A[D]) ?=> a.C): Any = ???
        
apply(())
```

## Output (click arrow to expand)

<details>

```scala
Exception in thread "main" java.lang.AssertionError: assertion failed: `wildApprox` failed to remove uninstantiated D
        at scala.runtime.Scala3RunTime$.assertFailed(Scala3RunTime.scala:8)
        at dotty.tools.dotc.typer.ImplicitRunInfo$collectParts$2$.traverse(Implicits.scala:674)
        at dotty.tools.dotc.core.Types$TypeTraverser.apply(Types.scala:6977)
        at dotty.tools.dotc.core.Types$TypeTraverser.apply(Types.scala:6977)
        at dotty.tools.dotc.core.Types$TypeAccumulator.foldOver(Types.scala:6904)
        at dotty.tools.dotc.core.Types$TypeTraverser.traverseChildren(Types.scala:6978)
        at dotty.tools.dotc.typer.ImplicitRunInfo$collectParts$2$.traverse(Implicits.scala:682)
        at dotty.tools.dotc.core.Types$TypeTraverser.apply(Types.scala:6977)
        at dotty.tools.dotc.core.Types$TypeTraverser.apply(Types.scala:6977)
        at dotty.tools.dotc.core.Types$TypeAccumulator.op$proxy28$1(Types.scala:6887)
        at dotty.tools.dotc.core.Types$TypeAccumulator.foldArgs$3(Types.scala:6887)
        at dotty.tools.dotc.core.Types$TypeAccumulator.foldOver(Types.scala:6891)
        at dotty.tools.dotc.core.Types$TypeTraverser.traverseChildren(Types.scala:6978)
        at dotty.tools.dotc.typer.ImplicitRunInfo$collectParts$2$.traverse(Implicits.scala:682)
        at dotty.tools.dotc.typer.ImplicitRunInfo$collectParts$2$.traverse(Implicits.scala:665)
        at dotty.tools.dotc.typer.ImplicitRunInfo$collectParts$2$.traverse(Implicits.scala:660)
        at dotty.tools.dotc.core.Types$TypeTraverser.apply(Types.scala:6977)
        at dotty.tools.dotc.core.Types$TypeTraverser.apply(Types.scala:6977)
        at dotty.tools.dotc.typer.ProtoTypes$ViewProto.fold(ProtoTypes.scala:676)
        at dotty.tools.dotc.core.Types$TypeAccumulator.foldOver(Types.scala:6940)
        at dotty.tools.dotc.core.Types$TypeTraverser.traverseChildren(Types.scala:6978)
        at dotty.tools.dotc.typer.ImplicitRunInfo$collectParts$2$.traverse(Implicits.scala:682)
        at dotty.tools.dotc.typer.ImplicitRunInfo$collectParts$2$.apply(Implicits.scala:688)
        at dotty.tools.dotc.typer.ImplicitRunInfo.recur$1(Implicits.scala:764)
        at dotty.tools.dotc.typer.ImplicitRunInfo.computeIScope(Implicits.scala:775)
        at dotty.tools.dotc.typer.ImplicitRunInfo.implicitScope(Implicits.scala:856)
        at dotty.tools.dotc.typer.ImplicitRunInfo.implicitScope$(Implicits.scala:626)
        at dotty.tools.dotc.Run.implicitScope(Run.scala:45)
        at dotty.tools.dotc.typer.Implicits$ImplicitSearch.implicitScope(Implicits.scala:1809)
        at dotty.tools.dotc.typer.Implicits$ImplicitSearch.searchImplicit(Implicits.scala:1691)
        at dotty.tools.dotc.typer.Implicits$ImplicitSearch.searchImplicit$$anonfun$3(Implicits.scala:1778)
        at dotty.tools.dotc.typer.Implicits$SearchResult.recoverWith(Implicits.scala:430)
        at dotty.tools.dotc.typer.Implicits$ImplicitSearch.searchImplicit(Implicits.scala:1764)
        at dotty.tools.dotc.typer.Implicits$ImplicitSearch.bestImplicit(Implicits.scala:1805)
        at dotty.tools.dotc.typer.Implicits.inferImplicit(Implicits.scala:1119)
        at dotty.tools.dotc.typer.Implicits.inferImplicit$(Implicits.scala:870)
        at dotty.tools.dotc.typer.Typer.inferImplicit(Typer.scala:155)
        at dotty.tools.dotc.typer.Implicits.inferView(Implicits.scala:910)
        at dotty.tools.dotc.typer.Implicits.inferView$(Implicits.scala:870)
        at dotty.tools.dotc.typer.Typer.inferView(Typer.scala:155)
        at dotty.tools.dotc.typer.Typer.adaptToSubType$1(Typer.scala:4875)
        at dotty.tools.dotc.typer.Typer.adaptNoArgsOther$1(Typer.scala:4685)
        at dotty.tools.dotc.typer.Typer.adaptNoArgs$1(Typer.scala:4765)
        at dotty.tools.dotc.typer.Typer.adapt1(Typer.scala:5028)
        at dotty.tools.dotc.typer.Typer.adapt(Typer.scala:4237)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3857)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3862)
        at dotty.tools.dotc.typer.Typer.typedExpr(Typer.scala:3973)
        at dotty.tools.dotc.typer.Typer.$anonfun$69(Typer.scala:3033)
        at dotty.tools.dotc.inlines.PrepareInlineable$.dropInlineIfError(PrepareInlineable.scala:256)
        at dotty.tools.dotc.typer.Typer.typedDefDef(Typer.scala:3033)
        at dotty.tools.dotc.typer.Typer.typedNamed$1(Typer.scala:3658)
        at dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3769)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3857)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3862)
        at dotty.tools.dotc.typer.Typer.traverse$1(Typer.scala:3884)
        at dotty.tools.dotc.typer.Typer.typedStats(Typer.scala:3930)
        at dotty.tools.dotc.typer.Typer.typedBlockStats(Typer.scala:1516)
        at dotty.tools.dotc.typer.Typer.typedBlock(Typer.scala:1520)
        at dotty.tools.dotc.typer.Typer.typedUnnamed$1(Typer.scala:3684)
        at dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3770)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3857)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3862)
        at dotty.tools.dotc.typer.Typer.typedFunctionValue(Typer.scala:2007)
        at dotty.tools.dotc.typer.Typer.makeContextualFunction(Typer.scala:3833)
        at dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3767)
        at dotty.tools.dotc.typer.ProtoTypes$FunProto.$anonfun$7(ProtoTypes.scala:543)
        at dotty.tools.dotc.typer.ProtoTypes$FunProto.cacheTypedArg(ProtoTypes.scala:466)
        at dotty.tools.dotc.typer.ProtoTypes$FunProto.typedArg(ProtoTypes.scala:545)
        at dotty.tools.dotc.typer.Applications$ApplyToUntyped.typedArg(Applications.scala:1067)
        at dotty.tools.dotc.typer.Applications$ApplyToUntyped.typedArg(Applications.scala:1067)
        at dotty.tools.dotc.typer.Applications$Application.addTyped$1(Applications.scala:733)
        at dotty.tools.dotc.typer.Applications$Application.matchArgs(Applications.scala:816)
        at dotty.tools.dotc.typer.Applications$Application.init(Applications.scala:612)
        at dotty.tools.dotc.typer.Applications$TypedApply.<init>(Applications.scala:942)
        at dotty.tools.dotc.typer.Applications$ApplyToUntyped.<init>(Applications.scala:1066)
        at dotty.tools.dotc.typer.Applications.ApplyTo(Applications.scala:1364)
        at dotty.tools.dotc.typer.Applications.ApplyTo$(Applications.scala:472)
        at dotty.tools.dotc.typer.Typer.ApplyTo(Typer.scala:155)
        at dotty.tools.dotc.typer.Applications.simpleApply$1(Applications.scala:1154)
        at dotty.tools.dotc.typer.Applications.$anonfun$15(Applications.scala:1270)
        at dotty.tools.dotc.typer.Typer$.tryEither(Typer.scala:128)
        at dotty.tools.dotc.typer.Applications.realApply$1(Applications.scala:1289)
        at dotty.tools.dotc.typer.Applications.typedApply(Applications.scala:1338)
        at dotty.tools.dotc.typer.Applications.typedApply$(Applications.scala:472)
        at dotty.tools.dotc.typer.Typer.typedApply(Typer.scala:155)
        at dotty.tools.dotc.typer.Typer.typedUnnamed$1(Typer.scala:3676)
        at dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3770)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3857)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3862)
        at dotty.tools.dotc.typer.Typer.typedExpr(Typer.scala:3973)
        at dotty.tools.dotc.typer.Namer.typedAheadExpr$$anonfun$1(Namer.scala:1802)
        at dotty.tools.dotc.typer.Namer.typedAhead(Namer.scala:1792)
        at dotty.tools.dotc.typer.Namer.typedAheadExpr(Namer.scala:1802)
        at dotty.tools.dotc.typer.Namer.typedAheadRhs$1$$anonfun$1(Namer.scala:2224)
        at dotty.tools.dotc.inlines.PrepareInlineable$.dropInlineIfError(PrepareInlineable.scala:256)
        at dotty.tools.dotc.typer.Namer.typedAheadRhs$1(Namer.scala:2224)
        at dotty.tools.dotc.typer.Namer.rhsType$1(Namer.scala:2232)
        at dotty.tools.dotc.typer.Namer.cookedRhsType$1(Namer.scala:2257)
        at dotty.tools.dotc.typer.Namer.lhsType$1(Namer.scala:2258)
        at dotty.tools.dotc.typer.Namer.inferredResultType(Namer.scala:2270)
        at dotty.tools.dotc.typer.Namer.inferredType$1(Namer.scala:1845)
        at dotty.tools.dotc.typer.Namer.valOrDefDefSig(Namer.scala:1851)
        at dotty.tools.dotc.typer.Namer$Completer.typeSig(Namer.scala:837)
        at dotty.tools.dotc.typer.Namer$Completer.completeInCreationContext(Namer.scala:1005)
        at dotty.tools.dotc.typer.Namer$Completer.complete(Namer.scala:874)
        at dotty.tools.dotc.core.SymDenotations$SymDenotation.completeFrom(SymDenotations.scala:175)
        at dotty.tools.dotc.core.Denotations$Denotation.completeInfo$1(Denotations.scala:190)
        at dotty.tools.dotc.core.Denotations$Denotation.info(Denotations.scala:192)
        at dotty.tools.dotc.core.SymDenotations$SymDenotation.ensureCompleted(SymDenotations.scala:403)
        at dotty.tools.dotc.typer.Typer.retrieveSym(Typer.scala:3623)
        at dotty.tools.dotc.typer.Typer.typedNamed$1(Typer.scala:3648)
        at dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3769)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3857)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3862)
        at dotty.tools.dotc.typer.Typer.traverse$1(Typer.scala:3884)
        at dotty.tools.dotc.typer.Typer.typedStats(Typer.scala:3930)
        at dotty.tools.dotc.typer.Typer.typedClassDef(Typer.scala:3333)
        at dotty.tools.dotc.typer.Typer.typedTypeOrClassDef$1(Typer.scala:3664)
        at dotty.tools.dotc.typer.Typer.typedNamed$1(Typer.scala:3668)
        at dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3769)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3857)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3862)
        at dotty.tools.dotc.typer.Typer.traverse$1(Typer.scala:3884)
        at dotty.tools.dotc.typer.Typer.typedStats(Typer.scala:3930)
        at dotty.tools.dotc.typer.Typer.typedPackageDef(Typer.scala:3466)
        at dotty.tools.dotc.typer.Typer.typedUnnamed$1(Typer.scala:3710)
        at dotty.tools.dotc.typer.Typer.typedUnadapted(Typer.scala:3770)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3857)
        at dotty.tools.dotc.typer.Typer.typed(Typer.scala:3862)
        at dotty.tools.dotc.typer.Typer.typedExpr(Typer.scala:3973)
        at dotty.tools.dotc.typer.TyperPhase.typeCheck$$anonfun$1(TyperPhase.scala:47)
        at scala.runtime.function.JProcedure1.apply(JProcedure1.java:15)
        at scala.runtime.function.JProcedure1.apply(JProcedure1.java:10)
        at dotty.tools.dotc.core.Phases$Phase.monitor(Phases.scala:510)
        at dotty.tools.dotc.typer.TyperPhase.typeCheck(TyperPhase.scala:53)
        at dotty.tools.dotc.typer.TyperPhase.$anonfun$4(TyperPhase.scala:99)
        at scala.collection.Iterator$$anon$6.hasNext(Iterator.scala:479)
        at scala.collection.Iterator$$anon$9.hasNext(Iterator.scala:583)
        at scala.collection.immutable.List.prependedAll(List.scala:152)
        at scala.collection.immutable.List$.from(List.scala:685)
        at scala.collection.immutable.List$.from(List.scala:682)
        at scala.collection.IterableOps$WithFilter.map(Iterable.scala:900)
        at dotty.tools.dotc.typer.TyperPhase.runOn(TyperPhase.scala:98)
        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$$anonfun$adapted$1(Run.scala:432)
        at dotty.tools.dotc.util.Stats$.maybeMonitored(Stats.scala:69)
        at dotty.tools.dotc.Run.compileUnits(Run.scala:432)
        at dotty.tools.dotc.Run.compileUnits(Run.scala:325)
        at dotty.tools.repl.ReplCompiler.compile(ReplCompiler.scala:90)
        at dotty.tools.repl.ReplDriver.compile(ReplDriver.scala:341)
        at dotty.tools.repl.ReplDriver.interpret(ReplDriver.scala:303)
        at dotty.tools.repl.ReplDriver.loop$1(ReplDriver.scala:221)
        at dotty.tools.repl.ReplDriver.runUntilQuit$$anonfun$1(ReplDriver.scala:224)
        at dotty.tools.repl.ReplDriver.withRedirectedOutput(ReplDriver.scala:258)
        at dotty.tools.repl.ReplDriver.runBody$$anonfun$1(ReplDriver.scala:232)
        at dotty.tools.runner.ScalaClassLoader$.asContext(ScalaClassLoader.scala:79)
        at dotty.tools.repl.ReplDriver.runBody(ReplDriver.scala:232)
        at dotty.tools.repl.ReplDriver.runUntilQuit(ReplDriver.scala:224)
        at dotty.tools.repl.ReplDriver.tryRunning(ReplDriver.scala:161)
        at dotty.tools.repl.Main$.main(Main.scala:7)
        at dotty.tools.repl.Main.main(Main.scala)
```
</details>

As noted, this crash happens due to not being able to find an implicit `A[D]`. If code is structured in a way that type inference can determine D, and `A[D]` can be found, the code compiles and there's no crash.

```scala
trait A[B[_]]:
  type C

object A:
  given A[Option]:
    type C = Option[Int]
    
  def apply[E[_], F](e: E[F])(using a: A[E]): a.C = ???
  
def apply[D[_]](other: (a: A[D]) ?=> a.C): Any = ???
        
apply(A(Option(5))) //this compiles with no problem
apply(5) //crash
apply(Option(5)) //crash
```

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Implicit resolution search crashes when dealing with inferred path dependent context function types when inference involves higher kinded types and implicit cannot be found #25500

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Implicit resolution search crashes when dealing with inferred path dependent context function types when inference involves higher kinded types and implicit cannot be found #25500

Description

Compiler version

Minimized code

Output (click arrow to expand)

Metadata

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

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