Fix exception: Any and AnyVal don't have constructors

dotc -d out -Ycheck-init  tests/run/vc-equals.scala

Author: liufengyun

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

@@ -44,13 +44,17 @@ object Effects {
 
   /** Field access, `a.f` */
   case class FieldAccess(potential: Potential, field: Symbol)(val source: Tree) extends Effect {
+    assert(field != NoSymbol)
+
     def size: Int = potential.size
     def show(implicit ctx: Context): String =
       potential.show + "." + field.name.show + "!"
   }
 
   /** Method call, `a.m()` */
   case class MethodCall(potential: Potential, method: Symbol)(val source: Tree) extends Effect {
+    assert(method != NoSymbol)
+
     def size: Int = potential.size
     def show(implicit ctx: Context): String = potential.show + "." + method.name.show + "!"
   }

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

@@ -118,14 +118,18 @@ object Potentials {
 
   /** The object pointed by `this.f` */
   case class FieldReturn(potential: Potential, field: Symbol)(val source: Tree) extends Potential {
+    assert(field != NoSymbol)
+
     def size: Int = potential.size + 1
     def show(implicit ctx: Context): String = potential.show + "." + field.name.show
   }
 
   /** The object returned by `this.m()` */
-  case class MethodReturn(potential: Potential, symbol: Symbol)(val source: Tree) extends Potential {
+  case class MethodReturn(potential: Potential, method: Symbol)(val source: Tree) extends Potential {
+    assert(method != NoSymbol)
+
     def size: Int = potential.size + 1
-    def show(implicit ctx: Context): String = potential.show + "." + symbol.name.show
+    def show(implicit ctx: Context): String = potential.show + "." + method.name.show
   }
 
   /** The object whose initialization status is unknown */

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

@@ -288,9 +288,13 @@ object Summarization {
 
           case ref =>
             val tref: TypeRef = ref.tpe.typeConstructor.asInstanceOf
-            val ctor = tref.classSymbol.asClass.primaryConstructor
-            Summarization.analyze(tref.prefix, ref)._2 +
-              MethodCall(ThisRef(cls)(ref), ctor)(ref)
+            val cls = tref.classSymbol.asClass
+            if (cls == defn.AnyClass || cls == defn.AnyValClass) Effects.empty
+            else {
+              val ctor = cls.primaryConstructor
+              Summarization.analyze(tref.prefix, ref)._2 +
+                MethodCall(ThisRef(cls)(ref), ctor)(ref)
+            }
         })
       }