Set privateWithin when creating java inner classes

[Cherry-picked 350215d]

Author: dwijnand

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

@@ -103,13 +103,14 @@ object SymbolLoaders {
    */
   def enterClassAndModule(
       owner: Symbol, name: PreName, completer: SymbolLoader,
-      flags: FlagSet = EmptyFlags, scope: Scope = EmptyScope)(using Context): Unit = {
+      flags: FlagSet = EmptyFlags, scope: Scope = EmptyScope)(using Context): (Symbol, Symbol) = {
     val clazz = enterClass(owner, name, completer, flags, scope)
     val module = enterModule(
       owner, name, completer,
       modFlags = flags.toTermFlags & RetainedModuleValFlags,
       clsFlags = flags.toTypeFlags & RetainedModuleClassFlags,
       scope = scope)
+    (clazz, module)
   }
 
   /** Enter all toplevel classes and objects in file `src` into package `owner`, provided

compiler/src/dotty/tools/dotc/core/classfile/ClassfileParser.scala

@@ -401,12 +401,12 @@ class ClassfileParser(
       classRoot.setFlag(sflags)
       moduleRoot.setFlag(Flags.JavaDefined | Flags.ModuleClassCreationFlags)
 
-      val jflags1 = innerClasses.get(currentClassName.toString).fold(jflags: Int)(_.jflags)
-      val privateWithin = getPrivateWithin(jflags1)
+      val privateWithin = getPrivateWithin(jflags)
 
-      classRoot.setPrivateWithin(privateWithin)
-      moduleRoot.setPrivateWithin(privateWithin)
-      moduleRoot.sourceModule.setPrivateWithin(privateWithin)
+      if privateWithin.exists then
+        classRoot.setPrivateWithin(privateWithin)
+        moduleRoot.setPrivateWithin(privateWithin)
+        moduleRoot.sourceModule.setPrivateWithin(privateWithin)
 
       for (i <- 0 until in.nextChar) parseMember(method = false)
       for (i <- 0 until in.nextChar) parseMember(method = true)
@@ -1059,13 +1059,18 @@ class ClassfileParser(
    */
   private def enterOwnInnerClasses()(using Context, DataReader): Unit = {
     def enterClassAndModule(entry: InnerClassEntry, file: AbstractFile, jflags: Int) =
-      SymbolLoaders.enterClassAndModule(
+      val (cls, mod) = SymbolLoaders.enterClassAndModule(
           getOwner(jflags),
-          entry.originalName,
+        entry.originalName,
           new ClassfileLoader(file),
           classTranslation.flags(jflags),
           getScope(jflags))
 
+      val privateWithin = getPrivateWithin(jflags)
+      cls.setPrivateWithin(privateWithin)
+      mod.setPrivateWithin(privateWithin)
+      mod.sourceModule.setPrivateWithin(privateWithin)
+
     for entry <- innerClasses.valuesIterator do
       // create a new class member for immediate inner classes
       if entry.outer.name == currentClassName then