Fixes SI-6150 - backport to 2.10.x branch.

1 files changed, 3 insertions, 6 deletions

diff --git a/src/library/scala/collection/generic/GenTraversableFactory.scala b/src/library/scala/collection/generic/GenTraversableFactory.scala
index d5edf5961e..a43862abaf 100644
--- a/src/library/scala/collection/generic/GenTraversableFactory.scala
+++ b/src/library/scala/collection/generic/GenTraversableFactory.scala
@@ -36,15 +36,12 @@ import scala.language.higherKinds
  *    @see GenericCanBuildFrom
  */
 abstract class GenTraversableFactory[CC[X] <: GenTraversable[X] with GenericTraversableTemplate[X, CC]]
-  extends GenericCompanion[CC] {
+extends GenericCompanion[CC] {
 
-  // A default implementation of GenericCanBuildFrom which can be cast
-  // to whatever is desired.
-  private class ReusableCBF extends GenericCanBuildFrom[Nothing] {
+  private[this] val ReusableCBFInstance: GenericCanBuildFrom[Nothing] = new GenericCanBuildFrom[Nothing] {
     override def apply() = newBuilder[Nothing]
   }
-  // Working around SI-4789 by using a lazy val instead of an object.
-  lazy val ReusableCBF: GenericCanBuildFrom[Nothing] = new ReusableCBF
+  def ReusableCBF: GenericCanBuildFrom[Nothing] = ReusableCBFInstance
 
   /** A generic implementation of the `CanBuildFrom` trait, which forwards
    *  all calls to `apply(from)` to the `genericBuilder` method of