Add second test case from comment 1

tests/pos/i19942.1.scala

@@ -0,0 +1,29 @@
+trait Alternative[F[_]]
+
+opaque type Derived[A] = A
+object Derived:
+  extension [A](derived: Derived[A]) def instance: A = derived
+  infix type <<<[F[_], G[_]] = [x] =>> F[G[x]]
+
+import Derived.*
+import scala.compiletime.summonInline
+
+type DerivedAlternative[F[_]] = Derived[Alternative[F]]
+object DerivedAlternative:
+  inline def apply[F[_]]: Alternative[F] =
+    import DerivedAlternative.given
+    summonInline[DerivedAlternative[F]].instance
+  given nested[F[_], G[_]]: DerivedAlternative[F <<< G] = ???
+
+object auto:
+  object alternative:
+    transparent inline given [F[_]]: Alternative[F] = DerivedAlternative[F]
+
+trait Test:
+  import Test.*
+  import auto.alternative.given
+  val fails = summon[Alternative[OptList]]
+
+// Fails if companion object defined AFTER trait
+object Test:
+  type OptList[A] = Option[List[A]]