gistfile1.txt

tail sandbox/test{1,2}.scala
==> sandbox/test1.scala <==
class C { class Inner }

class D {
  object O {
    def foo(c: C)(i: c.Inner): c.Inner = ???
  }
}

==> sandbox/test2.scala <==
class E {
  def foo = {
    (null: D).toString
  }
}

% for v in v2.11.2 v2.11.3 quick; do echo $v; scalac-hash $v sandbox/test1.scala && rm C.class && scalac-hash $v sandbox/test2.scala; done
v2.11.2
v2.11.3
error: missing or invalid dependency detected while loading class file 'D.class'.
Could not access type C in package <empty>,
because it (or its dependencies) are missing. Check your build definition for
missing or conflicting dependencies. (Re-run with `-Ylog-classpath` to see the problematic classpath.)
A full rebuild may help if 'D.class' was compiled against an incompatible version of <empty>.
one error found
quick


% git --no-pager diff
diff --git a/src/compiler/scala/tools/nsc/backend/jvm/BCodeAsmCommon.scala b/src/compiler/scala/tools/nsc/backend/jvm/BCodeAsmCommon.scala
index 4285858..51f7f33 100644
--- a/src/compiler/scala/tools/nsc/backend/jvm/BCodeAsmCommon.scala
+++ b/src/compiler/scala/tools/nsc/backend/jvm/BCodeAsmCommon.scala
@@ -32,7 +32,8 @@ final class BCodeAsmCommon[G <: Global](val global: G) {
     assert(classSym.isClass, s"not a class: $classSym")
     val res = (classSym.isAnonymousClass || !classSym.originalOwner.isClass)
     // lambda classes are always top-level classes.
-    if (res) assert(!classSym.isDelambdafyFunction)
+    if (res)
+      assert(!classSym.isDelambdafyFunction, s"${classSym.pos } ${classSym.name}")
     res
   }

diff --git a/src/reflect/scala/reflect/internal/Symbols.scala b/src/reflect/scala/reflect/internal/Symbols.scala
index b0c23ef..1d986a4 100644
--- a/src/reflect/scala/reflect/internal/Symbols.scala
+++ b/src/reflect/scala/reflect/internal/Symbols.scala
@@ -2700,6 +2700,9 @@ trait Symbols extends api.Symbols { self: SymbolTable =>
       if (isSingletonExistential && !settings.debug.value)
         "val " + tpnme.dropSingletonName(name) + ": " + dropSingletonType(info.bounds.hi)
       else defString
+
+    /** The error message describing the provenance of a StubSymbol, or the empty string for other symbols. */
+    def missingMessage: String = ""
   }
   implicit val SymbolTag = ClassTag[Symbol](classOf[Symbol])

@@ -3453,8 +3456,8 @@ trait Symbols extends api.Symbols { self: SymbolTable =>
     override def rawInfo         = fail(NoType)
     override def companionSymbol = fail(NoSymbol)
   }
-  class StubClassSymbol(owner0: Symbol, name0: TypeName, protected val missingMessage: String) extends ClassSymbol(owner0, owner0.pos, name0) with StubSymbol
-  class StubTermSymbol(owner0: Symbol, name0: TermName, protected val missingMessage: String) extends TermSymbol(owner0, owner0.pos, name0) with StubSymbol
+  class StubClassSymbol(owner0: Symbol, name0: TypeName, override val missingMessage: String) extends ClassSymbol(owner0, owner0.pos, name0) with StubSymbol
+  class StubTermSymbol(owner0: Symbol, name0: TermName, override val missingMessage: String) extends TermSymbol(owner0, owner0.pos, name0) with StubSymbol

   trait FreeSymbol extends Symbol {
     def origin: String
diff --git a/src/reflect/scala/reflect/internal/Types.scala b/src/reflect/scala/reflect/internal/Types.scala
index a95f626..02806ab 100644
--- a/src/reflect/scala/reflect/internal/Types.scala
+++ b/src/reflect/scala/reflect/internal/Types.scala
@@ -1188,9 +1188,14 @@ trait Types

   object ThisType extends ThisTypeExtractor {
     def apply(sym: Symbol): Type = (
-      if (!phase.erasedTypes) unique(new UniqueThisType(sym))
-      else if (sym.isImplClass) sym.typeOfThis
-      else sym.tpe_*
+      sym match {
+        case stub: StubTermSymbol =>
+          apply(sym.owner.newStubSymbol(sym.name.toTypeName, stub.missingMessage))
+        case _ =>
+          if (!phase.erasedTypes) unique(new UniqueThisType(sym))
+          else if (sym.isImplClass) sym.typeOfThis
+          else sym.tpe_*
+      }
     )
   }

diff --git a/src/reflect/scala/reflect/internal/pickling/UnPickler.scala b/src/reflect/scala/reflect/internal/pickling/UnPickler.scala
index 5433bfa..e50568b 100644
--- a/src/reflect/scala/reflect/internal/pickling/UnPickler.scala
+++ b/src/reflect/scala/reflect/internal/pickling/UnPickler.scala
@@ -208,9 +208,12 @@ abstract class UnPickler {

         def adjust(sym: Symbol) = if (tag == EXTref) sym else sym.moduleClass

+        def isStub = owner.isInstanceOf[StubSymbol]
+
         def fromName(name: Name) = name.toTermName match {
           case nme.ROOT     => loadingMirror.RootClass
           case nme.ROOTPKG  => loadingMirror.RootPackage
+          case _ if isStub  => owner.newStubSymbol(name, owner.missingMessage)
           case _            => adjust(owner.info.decl(name))
         }
         def nestedObjectSymbol: Symbol = {