diff --git a/compiler/src/dotty/tools/dotc/ast/TreeInfo.scala b/compiler/src/dotty/tools/dotc/ast/TreeInfo.scala
index 2e1b674b895e..9cde7305300f 100644
--- a/compiler/src/dotty/tools/dotc/ast/TreeInfo.scala
+++ b/compiler/src/dotty/tools/dotc/ast/TreeInfo.scala
@@ -542,19 +542,6 @@ trait TypedTreeInfo extends TreeInfo[Type] { self: Trees.Instance[Type] =>
     case _ => false
   }
 
-  /** Strips layers of `.asInstanceOf[T]` / `_.$asInstanceOf[T]()` from an expression */
-  def stripCast(tree: Tree)(implicit ctx: Context): Tree = {
-    def isCast(sel: Tree) = sel.symbol == defn.Any_asInstanceOf
-    unsplice(tree) match {
-      case TypeApply(sel @ Select(inner, _), _) if isCast(sel) =>
-        stripCast(inner)
-      case Apply(TypeApply(sel @ Select(inner, _), _), Nil) if isCast(sel) =>
-        stripCast(inner)
-      case t =>
-        t
-    }
-  }
-
   /** Decompose a call fn[targs](vargs_1)...(vargs_n)
    *  into its constituents (fn, targs, vargss).
    *
diff --git a/compiler/src/dotty/tools/dotc/core/Phases.scala b/compiler/src/dotty/tools/dotc/core/Phases.scala
index 0269c6f536ee..33c5808a0000 100644
--- a/compiler/src/dotty/tools/dotc/core/Phases.scala
+++ b/compiler/src/dotty/tools/dotc/core/Phases.scala
@@ -84,7 +84,6 @@ object Phases {
                              phasesToSkip: List[String], stopBeforePhases: List[String], stopAfterPhases: List[String], YCheckAfter: List[String]): List[Phase] = {
       val squashedPhases = ListBuffer[Phase]()
       var prevPhases: Set[String] = Set.empty
-      val YCheckAll = YCheckAfter.contains("all")
 
       var stop = false
       val filteredPhases = phasess.map(_.filter { p =>
@@ -120,7 +119,7 @@ object Phases {
               phase
             }
           squashedPhases += phaseToAdd
-          val shouldAddYCheck = YCheckAfter.containsPhase(phaseToAdd) || YCheckAll
+          val shouldAddYCheck = YCheckAfter.containsPhase(phaseToAdd)
           if (shouldAddYCheck) {
             val checker = new TreeChecker
             squashedPhases += checker
diff --git a/compiler/src/dotty/tools/dotc/core/quoted/PickledQuotes.scala b/compiler/src/dotty/tools/dotc/core/quoted/PickledQuotes.scala
index bedcd8c05724..eaa3684d03c8 100644
--- a/compiler/src/dotty/tools/dotc/core/quoted/PickledQuotes.scala
+++ b/compiler/src/dotty/tools/dotc/core/quoted/PickledQuotes.scala
@@ -22,12 +22,6 @@ import scala.reflect.ClassTag
 object PickledQuotes {
   import tpd._
 
-  /** Pickle the tree of the quoted.Expr */
-  def pickleExpr(tree: Tree)(implicit ctx: Context): scala.quoted.Expr[Any] = {
-    val pickled = pickleQuote(tree)
-    scala.runtime.quoted.Unpickler.unpickleExpr(pickled, Nil)
-  }
-
   /** Pickle the tree of the quote into strings */
   def pickleQuote(tree: Tree)(implicit ctx: Context): scala.runtime.quoted.Unpickler.Pickled = {
     if (ctx.reporter.hasErrors) Nil
diff --git a/compiler/src/dotty/tools/dotc/transform/TypeTestsCasts.scala b/compiler/src/dotty/tools/dotc/transform/TypeTestsCasts.scala
index 1bffe1372586..5c8af165788d 100644
--- a/compiler/src/dotty/tools/dotc/transform/TypeTestsCasts.scala
+++ b/compiler/src/dotty/tools/dotc/transform/TypeTestsCasts.scala
@@ -140,7 +140,15 @@ object TypeTestsCasts {
   }
 
   def interceptTypeApply(tree: TypeApply)(implicit ctx: Context): Tree = trace(s"transforming ${tree.show}", show = true) {
-    tree.fun match {
+    interceptTypeApply1(tree, tree.fun match {
+      case i: Ident =>
+        desugarIdent(i).withPos(tree.fun)
+      case t => t
+    })
+  }
+
+  private def interceptTypeApply1(tree: TypeApply, treeFun: Tree)(implicit ctx: Context): Tree = {
+    treeFun match {
       case fun @ Select(expr, selector) =>
         val sym = tree.symbol
 
diff --git a/compiler/src/dotty/tools/dotc/typer/Implicits.scala b/compiler/src/dotty/tools/dotc/typer/Implicits.scala
index feb6bc391a55..546cce74aaf7 100644
--- a/compiler/src/dotty/tools/dotc/typer/Implicits.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Implicits.scala
@@ -552,6 +552,7 @@ trait Implicits { self: Typer =>
         || (from.tpe isRef defn.NothingClass)
         || (from.tpe isRef defn.NullClass)
         || !(ctx.mode is Mode.ImplicitsEnabled)
+        || from.isInstanceOf[Super]
         || (from.tpe eq NoPrefix)) NoMatchingImplicitsFailure
     else {
       def adjust(to: Type) = to.stripTypeVar.widenExpr match {
diff --git a/compiler/src/dotty/tools/dotc/typer/Namer.scala b/compiler/src/dotty/tools/dotc/typer/Namer.scala
index f8d83964e82b..0d116a5ea47c 100644
--- a/compiler/src/dotty/tools/dotc/typer/Namer.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Namer.scala
@@ -1158,8 +1158,9 @@ class Namer { typer: Typer =>
 
   /** The type signature of a DefDef with given symbol */
   def defDefSig(ddef: DefDef, sym: Symbol)(implicit ctx: Context) = {
-    val DefDef(name, tparams, vparamss, _, _) = ddef
-    val isConstructor = name == nme.CONSTRUCTOR
+    // Beware: ddef.name need not match sym.name if sym was freshened!
+    val DefDef(_, tparams, vparamss, _, _) = ddef
+    val isConstructor = sym.name == nme.CONSTRUCTOR
 
     // The following 3 lines replace what was previously just completeParams(tparams).
     // But that can cause bad bounds being computed, as witnessed by
diff --git a/compiler/src/dotty/tools/dotc/typer/Typer.scala b/compiler/src/dotty/tools/dotc/typer/Typer.scala
index 240999864503..d5eb642d4336 100644
--- a/compiler/src/dotty/tools/dotc/typer/Typer.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Typer.scala
@@ -355,7 +355,7 @@ class Typer extends Namer
     }
 
     // begin typedIdent
-    def kind = if (name.isTermName) "" else "type "
+    def kind = if (name.isTermName) "value " else "type "
     typr.println(s"typed ident $kind$name in ${ctx.owner}")
     if (ctx.mode is Mode.Pattern) {
       if (name == nme.WILDCARD)
@@ -1524,6 +1524,7 @@ class Typer extends Namer
         ctx.error(i"$psym is extended twice", tree.pos)
       seenParents += psym
       if (tree.isType) {
+        checkSimpleKinded(result) // Not needed for constructor calls, as type arguments will be inferred.
         if (psym.is(Trait) && !cls.is(Trait) && !cls.superClass.isSubClass(psym))
           result = maybeCall(result, psym, psym.primaryConstructor.info)
       }
@@ -1576,6 +1577,15 @@ class Typer extends Namer
       if (!cls.is(AbstractOrTrait) && !ctx.isAfterTyper)
         checkRealizableBounds(cls, cdef.namePos)
       if (cls.is(Case) && cls.derivesFrom(defn.EnumClass)) checkEnum(cdef, cls)
+      if (seenParents.contains(defn.EnumClass)) {
+        // Since enums are classes and Namer checks that classes don't extend multiple classes, we only check the class
+        // parent.
+        val firstParent = parents1.head.tpe.dealias.typeSymbol
+        if (firstParent.derivesFrom(defn.EnumClass))
+          //Tricky to phrase; language taken from "case-to-case inheritance is prohibited".
+          ctx.error(s"Enum ${cls.name} has enum ancestor ${firstParent.name}, but enum-to-enum inheritance is prohibited", cdef.pos)
+      }
+
       val cdef1 = assignType(cpy.TypeDef(cdef)(name, impl1), cls)
       if (ctx.phase.isTyper && cdef1.tpe.derivesFrom(defn.DynamicClass) && !ctx.dynamicsEnabled) {
         val isRequired = parents1.exists(_.tpe.isRef(defn.DynamicClass))
@@ -1793,7 +1803,7 @@ class Typer extends Namer
       case none =>
 
         def typedNamed(tree: untpd.NameTree, pt: Type)(implicit ctx: Context): Tree = {
-          val sym = retrieveSym(xtree)
+          val sym = retrieveSym(tree)
           tree match {
             case tree: untpd.Ident => typedIdent(tree, pt)
             case tree: untpd.Select => typedSelect(tree, pt)
diff --git a/tests/neg/i1643.scala b/tests/neg/i1643.scala
index 889233b3a0ca..1e3affa7f1c9 100644
--- a/tests/neg/i1643.scala
+++ b/tests/neg/i1643.scala
@@ -1,4 +1,4 @@
-trait T extends Array { // error
+trait T extends Array { // error // error
   def t1(as: String*): Array[String] = { varargs1(as: _*) } // error
   def t2(as: String*): Array[String] = { super.varargs1(as: _*) } // error
 }
diff --git a/tests/neg/i5006.scala b/tests/neg/i5006.scala
new file mode 100644
index 000000000000..94169286322e
--- /dev/null
+++ b/tests/neg/i5006.scala
@@ -0,0 +1,7 @@
+object i0 {
+  // Adding anything in front of asInstanceOf,
+  // i0 or this, makes the error go away.
+  def i1: Int = asInstanceOf[Int].toInt
+
+  val i2 = asInstanceOf[Int]
+}
diff --git a/tests/neg/i5008.scala b/tests/neg/i5008.scala
new file mode 100644
index 000000000000..2c856a07c334
--- /dev/null
+++ b/tests/neg/i5008.scala
@@ -0,0 +1,5 @@
+enum Foo { case A }
+enum Bar { case A }
+enum Baz extends Foo { case Z } // error
+
+enum Quux extends Foo with Bar { case Z } // error
diff --git a/tests/neg/i5010.scala b/tests/neg/i5010.scala
new file mode 100644
index 000000000000..7cdf67c8135b
--- /dev/null
+++ b/tests/neg/i5010.scala
@@ -0,0 +1 @@
+class i0 extends Function0 // error
diff --git a/tests/neg/parser-stability-16.scala b/tests/neg/parser-stability-16.scala
index f6f6f19aa890..25fb38374c45 100644
--- a/tests/neg/parser-stability-16.scala
+++ b/tests/neg/parser-stability-16.scala
@@ -1,5 +1,5 @@
 class x0[x0] {
   val x1 : x0
 }
-trait x3 extends x0 {
+trait x3 extends x0 { // error
 x1 = 0 object  // error // error
diff --git a/tests/neg/parser-stability-7.scala b/tests/neg/parser-stability-7.scala
index 98ed2cb009a1..27d391ed9396 100644
--- a/tests/neg/parser-stability-7.scala
+++ b/tests/neg/parser-stability-7.scala
@@ -1,7 +1,7 @@
 class x0[x1] {
 def x2: x1
 }
-trait x3 extends x0 {
+trait x3 extends x0 { // error
 class x2
 var x2 = 0     // error
 var x4 = x5 x2 // error
diff --git a/tests/neg/t5063.scala b/tests/neg/t5063.scala
new file mode 100644
index 000000000000..0566e90798f5
--- /dev/null
+++ b/tests/neg/t5063.scala
@@ -0,0 +1,3 @@
+class A {
+  super.+("") // error
+}
diff --git a/tests/pending/neg/i5008 b/tests/pending/neg/i5008
deleted file mode 100644
index 2dc75e6b199c..000000000000
--- a/tests/pending/neg/i5008
+++ /dev/null
@@ -1,2 +0,0 @@
-enum Foo {}
-enum Bar extends Foo {} // error
diff --git a/tests/run/t3613.scala b/tests/run/t3613.scala
index 1293f62c0fd4..199ed2ee1933 100644
--- a/tests/run/t3613.scala
+++ b/tests/run/t3613.scala
@@ -2,7 +2,7 @@ class Boopy {
     private val s = new Schnuck
     def observer : PartialFunction[ Any, Unit ] = s.observer
 
-    private class Schnuck extends javax.swing.AbstractListModel {
+    private class Schnuck extends javax.swing.AbstractListModel[Nothing] {
         model =>
         val observer : PartialFunction[ Any, Unit ] = {
             case "Boopy" => fireIntervalAdded( model, 0, 1 )
diff --git a/tests/untried/neg/t5063.check b/tests/untried/neg/t5063.check
deleted file mode 100644
index c6e553c1b5f6..000000000000
--- a/tests/untried/neg/t5063.check
+++ /dev/null
@@ -1,4 +0,0 @@
-t5063.scala:2: error: value + is not a member of AnyRef
-  super.+("")
-        ^
-one error found
diff --git a/tests/untried/neg/t5063.scala b/tests/untried/neg/t5063.scala
deleted file mode 100644
index 5b34b53fb7fc..000000000000
--- a/tests/untried/neg/t5063.scala
+++ /dev/null
@@ -1,3 +0,0 @@
-class A {
-  super.+("")
-}