Merge pull request #2236 from retronym/ticket/6601-2

SI-6601 Close access loophole for value class constructors

8 files changed, 33 insertions, 2 deletions

diff --git a/src/compiler/scala/tools/nsc/symtab/classfile/Pickler.scala b/src/compiler/scala/tools/nsc/symtab/classfile/Pickler.scala
index 140be0e17b..9b33ae8ba1 100644
--- a/src/compiler/scala/tools/nsc/symtab/classfile/Pickler.scala
+++ b/src/compiler/scala/tools/nsc/symtab/classfile/Pickler.scala
@@ -528,7 +528,7 @@ abstract class Pickler extends SubComponent {
     private def writeSymInfo(sym: Symbol) {
       writeRef(sym.name)
       writeRef(localizedOwner(sym))
-      writeLongNat((rawToPickledFlags(sym.flags & PickledFlags)))
+      writeLongNat((rawToPickledFlags(sym.rawflags & PickledFlags)))
       if (sym.hasAccessBoundary) writeRef(sym.privateWithin)
       writeRef(sym.info)
     }
diff --git a/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala b/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala
index b7221a78ec..b32fc6b977 100644
--- a/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala
@@ -1553,6 +1553,8 @@ abstract class RefChecks extends InfoTransform with scala.reflect.internal.trans
             val bridges = addVarargBridges(currentOwner)
             checkAllOverrides(currentOwner)
             checkAnyValSubclass(currentOwner)
+            if (currentOwner.isDerivedValueClass)
+              currentOwner.primaryConstructor makeNotPrivate NoSymbol // SI-6601, must be done *after* pickler!
             if (bridges.nonEmpty) deriveTemplate(tree)(_ ::: bridges) else tree
 
           case dc@TypeTreeWithDeferredRefCheck() => abort("adapt should have turned dc: TypeTreeWithDeferredRefCheck into tpt: TypeTree, with tpt.original == dc")
diff --git a/src/reflect/scala/reflect/internal/Flags.scala b/src/reflect/scala/reflect/internal/Flags.scala
index 1987f34474..fe46a0471e 100644
--- a/src/reflect/scala/reflect/internal/Flags.scala
+++ b/src/reflect/scala/reflect/internal/Flags.scala
@@ -307,7 +307,11 @@ class Flags extends ModifierFlags {
   assert((OverloadedFlagsMask & FlagsNotPickled) == 0, flagsToString(OverloadedFlagsMask & FlagsNotPickled))
 
   /** These flags are pickled */
-  final val PickledFlags  = InitialFlags & ~FlagsNotPickled
+  final val PickledFlags  = (
+      (InitialFlags & ~FlagsNotPickled)
+    | notPRIVATE // for value class constructors (SI-6601), and private members referenced
+                 // in @inline-marked methods publicized in SuperAccessors (see SI-6608, e6b4204604)
+  )
 
   /** If we have a top-level class or module
    *  and someone asks us for a flag not in TopLevelPickledFlags,
diff --git a/test/files/neg/t6601.check b/test/files/neg/t6601.check
new file mode 100644
index 0000000000..1410e1b11a
--- /dev/null
+++ b/test/files/neg/t6601.check
@@ -0,0 +1,4 @@
+AccessPrivateConstructor_2.scala:2: error: constructor PrivateConstructor in class PrivateConstructor cannot be accessed in class AccessPrivateConstructor
+  new PrivateConstructor("") // Scalac should forbid accessing to the private constructor!
+  ^
+one error found
diff --git a/test/files/neg/t6601/AccessPrivateConstructor_2.scala b/test/files/neg/t6601/AccessPrivateConstructor_2.scala
new file mode 100644
index 0000000000..816bc10d79
--- /dev/null
+++ b/test/files/neg/t6601/AccessPrivateConstructor_2.scala
@@ -0,0 +1,3 @@
+class AccessPrivateConstructor {
+  new PrivateConstructor("") // Scalac should forbid accessing to the private constructor!
+}
diff --git a/test/files/neg/t6601/PrivateConstructor_1.scala b/test/files/neg/t6601/PrivateConstructor_1.scala
new file mode 100644
index 0000000000..f09d7ad068
--- /dev/null
+++ b/test/files/neg/t6601/PrivateConstructor_1.scala
@@ -0,0 +1 @@
+class PrivateConstructor private(val s: String) extends AnyVal
diff --git a/test/files/run/t6608.check b/test/files/run/t6608.check
new file mode 100644
index 0000000000..15628b322e
--- /dev/null
+++ b/test/files/run/t6608.check
@@ -0,0 +1 @@
+(C$$yyy,true)
diff --git a/test/files/run/t6608.scala b/test/files/run/t6608.scala
new file mode 100644
index 0000000000..2f956bfb35
--- /dev/null
+++ b/test/files/run/t6608.scala
@@ -0,0 +1,16 @@
+import reflect.runtime.universe
+
+class C {
+  private val yyy: Any = 1
+  @inline def foo = yyy
+}
+
+object Test extends App {
+  import universe._
+  val access = typeOf[C].declarations
+    .toList
+    .filter(_.name.toString.endsWith("yyy"))
+    .map(x => (x.name, x.isPrivate))
+  println(access.head)
+}
+