closes #3507: don't generate manifests where we...

closes #3507: don't generate manifests where we can't refer to the
existentially bound value

3 files changed, 20 insertions, 1 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/Implicits.scala b/src/compiler/scala/tools/nsc/typechecker/Implicits.scala
index 3abaf4f337..4f1db5604a 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Implicits.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Implicits.scala
@@ -810,7 +810,7 @@ self: Analyzer =>
       def mot(tp0: Type): Tree = {
         val tp1 = tp0.normalize
         tp1 match {
-          case ThisType(_) | SingleType(_, _) =>
+          case ThisType(_) | SingleType(_, _) if !(tp1 exists {tp => tp.typeSymbol.isExistentiallyBound}) => // can't generate a reference to a value that's abstracted over by an existential
             manifestFactoryCall("singleType", tp, gen.mkAttributedQualifier(tp1))
           case ConstantType(value) =>
             manifestOfType(tp1.deconst, full)
diff --git a/test/files/neg/t3507.check b/test/files/neg/t3507.check
new file mode 100644
index 0000000000..1246a20d09
--- /dev/null
+++ b/test/files/neg/t3507.check
@@ -0,0 +1,4 @@
+t3507.scala:13: error: could not find implicit value for evidence parameter of type Manifest[object _1.b.c]
+  mani/*[object _1.b.c]*/(c) // kaboom in manifestOfType / TreeGen.mkAttributedQualifier
+                         ^
+one error found
diff --git a/test/files/neg/t3507.scala b/test/files/neg/t3507.scala
new file mode 100644
index 0000000000..9a8c7c5462
--- /dev/null
+++ b/test/files/neg/t3507.scala
@@ -0,0 +1,15 @@
+class A {
+  object b {
+    object c
+  }
+  def m = b.c
+}
+
+object Test {
+  var a: A = new A // mutable
+  val c /*: object _1.b.c forSome { val _1: A } */ = a.m // widening using existential
+
+  def mani[T: Manifest](x: T) = ()
+  mani/*[object _1.b.c]*/(c) // kaboom in manifestOfType / TreeGen.mkAttributedQualifier
+  // --> _1 is not in scope here
+}
\ No newline at end of file