Extract quote reification from Staging

Author: nicolasstucki

compiler/src/dotty/tools/dotc/Compiler.scala

@@ -46,7 +46,8 @@ class Compiler {
   /** Phases dealing with TASTY tree pickling and unpickling */
   protected def picklerPhases: List[List[Phase]] =
     List(new Pickler) ::            // Generate TASTY info
-    List(new Staging) ::            // Expand macros and turn quoted trees into explicit run-time data structures
+    List(new Staging) ::            // Check quotation levels (while healing types) and expand macros
+    List(new ReifyQuotes) ::        // Turn quoted trees into explicit run-time data structures
     Nil
 
   /** Phases dealing with the transformation from pickled trees to backend trees */

compiler/src/dotty/tools/dotc/quoted/TreeCleaner.scala

@@ -21,7 +21,7 @@ class TreeCleaner extends tpd.TreeMap {
 
   override def transform(tree: Tree)(implicit ctx: Context): Tree = {
     val tree0 = tree match {
-      case TypeDef(_, TypeBoundsTree(lo, hi)) if lo == hi =>
+      case TypeDef(_, TypeBoundsTree(lo, hi)) if lo.tpe =:= hi.tpe =>
         aliasesSyms = tree.symbol :: aliasesSyms
         aliasesTypes = lo.tpe :: aliasesTypes
         aliases(tree.symbol) = ref(lo.tpe.typeSymbol)