Intersection types made specializable.

Formerly a specializable type parameter would be missed if in
an intersection.

  trait Trait[@specialized T] {
    def f[T](x: Foo[T] with Bar) = x
  }

Now that is specialized, as it already was in the "Foo[T]" case.
Closes SI-4794, no review.

git-svn-id: http://lampsvn.epfl.ch/svn-repos/scala/scala/trunk@25613 5e8d7ff9-d8ef-0310-90f0-a4852d11357a

src/compiler/scala/tools/nsc/transform/SpecializeTypes.scala

@@ -346,6 +346,7 @@ abstract class SpecializeTypes extends InfoTransform with TypingTransformers {
     case ExistentialType(_, res)     => specializedTypeVars(res)
     case AnnotatedType(_, tp, _)     => specializedTypeVars(tp)
     case TypeBounds(lo, hi)          => specializedTypeVars(List(lo, hi))
+    case RefinedType(parents, _)     => parents flatMap specializedTypeVars toSet
     case _                           => Set()
   }
   

test/files/run/t4794.check

@@ -0,0 +1 @@
+10

test/files/run/t4794.scala

@@ -0,0 +1,12 @@
+trait Mutable[@specialized A] { def a: A; def a_=(a0: A): Unit }
+trait NotSpecialized { }
+class Arr[@specialized A](val arr: Array[A]) {
+  def bippy(m: Mutable[A]) { m.a = arr(0) }
+  def quux(m: Mutable[A] with NotSpecialized) { m.a = arr(0) }
+}
+
+object Test {
+  def main(args: Array[String]): Unit = {
+    println(classOf[Arr[_]].getMethods filter (_.getName contains "quux") size) // expect 10, not 1
+  }
+}