% git log --oneline  ca9f64d~7 -2
725c5c9 Encapsulate reporting mode as class of reportBuffer.
f0fdcc0 Clarify that ThrowErrors is the default

% scalac-hash f0fdcc0 test/benchmarks/src/scala/collection/parallel/benchmarks/arrays/Resetting.scala
test/benchmarks/src/scala/collection/parallel/benchmarks/arrays/Resetting.scala:3: error: cannot find class tag for element type T
  gencastarray = new Array[T](0)
                 ^
one error found

% scalac-hash 725c5c9 test/benchmarks/src/scala/collection/parallel/benchmarks/arrays/Resetting.scala 2>&1 | head -n 10
error: java.lang.StackOverflowError
        at scala.reflect.internal.Types$SimpleTypeProxy$class.boundSyms(Types.scala:153)
        at scala.reflect.internal.Types$SingletonType.boundSyms(Types.scala:1076)
        at scala.reflect.internal.tpe.TypeMaps$SubstMap.apply(TypeMaps.scala:698)
        at scala.reflect.internal.tpe.TypeMaps$TypeMap.mapOver(TypeMaps.scala:110)
        at scala.reflect.internal.tpe.TypeMaps$SubstMap.apply(TypeMaps.scala:700)
        at scala.reflect.internal.tpe.TypeMaps$TypeMap.mapOver(TypeMaps.scala:148)
        at scala.reflect.internal.tpe.TypeMaps$SubstMap.apply(TypeMaps.scala:700)
        at scala.reflect.internal.Types$Type.subst(Types.scala:705)
        at scala.reflect.internal.Types$Type.instantiateTypeParams(Types.scala:470)

%  cat test/benchmarks/src/scala/collection/parallel/benchmarks/arrays/Resetting.scala
class Resetting[T] {
  var gencastarray: Any = null
  gencastarray = new Array[T](0)
}