Synchronize Symbol.defTree before analysis

Author: liufengyun

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

@@ -64,8 +64,8 @@ class Compiler {
          new CheckStatic,            // Check restrictions that apply to @static members
          new BetaReduce,             // Reduce closure applications
          new InlineVals,             // Check right hand-sides of an `inline val`s
-         new ExpandSAMs,             // Expand single abstract method closures to anonymous classes
-         new init.Checker) ::        // Check initialization of objects
+         new ExpandSAMs) ::          // Expand single abstract method closures to anonymous classes
+    List(new init.Checker) ::        // Check initialization of objects
     List(new ElimRepeated,           // Rewrite vararg parameters and arguments
          new ProtectedAccessors,     // Add accessors for protected members
          new ExtensionMethods,       // Expand methods of value classes with extension methods

compiler/src/dotty/tools/dotc/core/Phases.scala

@@ -290,7 +290,7 @@ object Phases {
     /** If set, implicit search is enabled */
     def allowsImplicitSearch: Boolean = false
 
-     /** List of names of phases that should precede this phase */
+    /** List of names of phases that should precede this phase */
     def runsAfter: Set[String] = Set.empty
 
     /** @pre `isRunnable` returns true */

compiler/src/dotty/tools/dotc/transform/init/Checker.scala

@@ -10,15 +10,16 @@ import dotty.tools.dotc.core._
 import Contexts._
 import Types._
 import Symbols._
+import StdNames._
 
 import dotty.tools.dotc.transform._
-import MegaPhase._
+import Phases._
 
 
 import scala.collection.mutable
 
 
-class Checker extends MiniPhase {
+class Checker extends Phase {
   import tpd._
 
   val phaseName = "initChecker"
@@ -30,9 +31,34 @@ class Checker extends MiniPhase {
   override def isEnabled(using Context): Boolean =
     super.isEnabled && ctx.settings.YcheckInit.value
 
-  override def transformTypeDef(tree: TypeDef)(using Context): tpd.Tree = {
-    if (!tree.isClassDef) return tree
+  override def runOn(units: List[CompilationUnit])(using Context): List[CompilationUnit] =
+    units.foreach { unit => traverser.traverse(unit.tpdTree) }
+    super.runOn(units)
+
+  val traverser = new TreeTraverser {
+    override def traverse(tree: Tree)(using Context): Unit =
+      tree match {
+        case tdef: MemberDef =>
+          // self-type annotation ValDef has no symbol
+          if tdef.name != nme.WILDCARD then
+            tdef.symbol.defTree = tree
+        case _ =>
+          traverseChildren(tree)
+      }
+  }
+
+  override def run(using Context): Unit = {
+    val unit = ctx.compilationUnit
+    unit.tpdTree.foreachSubTree {
+      case tdef: TypeDef if tdef.isClassDef =>
+        transformTypeDef(tdef)
+
+      case _ =>
+    }
+  }
+
 
+  private def transformTypeDef(tree: TypeDef)(using Context): tpd.Tree = {
     val cls = tree.symbol.asClass
     val instantiable: Boolean =
       cls.is(Flags.Module) ||