[vpm] smarter type inference on when virtPatmat is on

3 files changed, 3 insertions, 1 deletions

diff --git a/src/compiler/scala/reflect/internal/Types.scala b/src/compiler/scala/reflect/internal/Types.scala
index 3ce8829af6..bb9549deba 100644
--- a/src/compiler/scala/reflect/internal/Types.scala
+++ b/src/compiler/scala/reflect/internal/Types.scala
@@ -97,7 +97,7 @@ trait Types extends api.Types { self: SymbolTable =>
    */
   private final val propagateParameterBoundsToTypeVars = sys.props contains "scalac.debug.prop-constraints"
 
-  protected val enableTypeVarExperimentals = settings.Xexperimental.value
+  protected val enableTypeVarExperimentals = settings.Xexperimental.value || settings.YvirtPatmat.value
 
   /** Empty immutable maps to avoid allocations. */
   private val emptySymMap   = immutable.Map[Symbol, Symbol]()
diff --git a/src/compiler/scala/reflect/internal/settings/MutableSettings.scala b/src/compiler/scala/reflect/internal/settings/MutableSettings.scala
index 0092f73fe3..b556c33aba 100644
--- a/src/compiler/scala/reflect/internal/settings/MutableSettings.scala
+++ b/src/compiler/scala/reflect/internal/settings/MutableSettings.scala
@@ -43,4 +43,5 @@ abstract class MutableSettings extends AbsSettings {
   def Yrecursion: IntSetting
   def maxClassfileName: IntSetting
   def Xexperimental: BooleanSetting
+  def YvirtPatmat: BooleanSetting
 }
\ No newline at end of file
diff --git a/src/compiler/scala/reflect/runtime/Settings.scala b/src/compiler/scala/reflect/runtime/Settings.scala
index 8b475da0d3..27e90c94bd 100644
--- a/src/compiler/scala/reflect/runtime/Settings.scala
+++ b/src/compiler/scala/reflect/runtime/Settings.scala
@@ -34,4 +34,5 @@ class Settings extends internal.settings.MutableSettings {
   val maxClassfileName = new IntSetting(255)
   val Xexperimental = new BooleanSetting(false)
   val deepCloning = new BooleanSetting (false)
+  val YvirtPatmat = new BooleanSetting(false)
 }