SI-8916 Further fixes with -Ywarn-unused included

11 files changed, 10 insertions, 18 deletions

diff --git a/build.xml b/build.xml
index bb617dc404..95f5c9c71f 100755
--- a/build.xml
+++ b/build.xml
@@ -471,7 +471,7 @@ TODO:
     <property name="scalac.args"           value=""/>
     <property name="javac.args"            value=""/>
 
-    <property name="scalac.args.always"    value="-feature -Ywarn-unused-import" />
+    <property name="scalac.args.always"    value="-feature -Ywarn-unused-import -Ywarn-unused" />
     <property name="scalac.args.optimise"  value=""/> <!-- scalac.args.optimise is selectively overridden in certain antcall tasks. -->
     <property name="scalac.args.all"       value="${scalac.args.always} ${scalac.args} ${scalac.args.optimise}"/>
     <property name="scalac.args.locker"    value="${scalac.args.all}"/>
diff --git a/src/compiler/scala/reflect/macros/util/Helpers.scala b/src/compiler/scala/reflect/macros/util/Helpers.scala
index a662d3b6c3..961c41dab5 100644
--- a/src/compiler/scala/reflect/macros/util/Helpers.scala
+++ b/src/compiler/scala/reflect/macros/util/Helpers.scala
@@ -54,13 +54,10 @@ trait Helpers {
    *
    *  @see Metalevels.scala for more information and examples about metalevels
    */
-  def increaseMetalevel(pre: Type, tp: Type): Type = {
-    val runDefinitions = currentRun.runDefinitions
-
+  def increaseMetalevel(pre: Type, tp: Type): Type =
     transparentShallowTransform(RepeatedParamClass, tp) {
       case tp => typeRef(pre, MacroContextExprClass, List(tp))
     }
-  }
 
   /** Transforms c.Expr[T] types into c.Tree and leaves the rest unchanged.
    */
diff --git a/src/compiler/scala/reflect/reify/codegen/GenUtils.scala b/src/compiler/scala/reflect/reify/codegen/GenUtils.scala
index a6492a43b8..de9fec0df5 100644
--- a/src/compiler/scala/reflect/reify/codegen/GenUtils.scala
+++ b/src/compiler/scala/reflect/reify/codegen/GenUtils.scala
@@ -5,7 +5,6 @@ trait GenUtils {
   self: Reifier =>
 
   import global._
-  private val runDefinitions = currentRun.runDefinitions
 
   def reifyList(xs: List[Any]): Tree =
     mkList(xs map reify)
diff --git a/src/compiler/scala/tools/nsc/Global.scala b/src/compiler/scala/tools/nsc/Global.scala
index 711f81d6c8..e7cbda9bf6 100644
--- a/src/compiler/scala/tools/nsc/Global.scala
+++ b/src/compiler/scala/tools/nsc/Global.scala
@@ -18,7 +18,7 @@ import scala.reflect.ClassTag
 import scala.reflect.internal.util.{ OffsetPosition, SourceFile, NoSourceFile, BatchSourceFile, ScriptSourceFile }
 import scala.reflect.internal.pickling.{ PickleBuffer, PickleFormat }
 import scala.reflect.io.VirtualFile
-import symtab.{ Flags, SymbolTable, SymbolLoaders, SymbolTrackers }
+import symtab.{ Flags, SymbolTable, SymbolTrackers }
 import symtab.classfile.Pickler
 import plugins.Plugins
 import ast._
diff --git a/src/compiler/scala/tools/nsc/transform/Erasure.scala b/src/compiler/scala/tools/nsc/transform/Erasure.scala
index 3d8b2f02f3..db639d0868 100644
--- a/src/compiler/scala/tools/nsc/transform/Erasure.scala
+++ b/src/compiler/scala/tools/nsc/transform/Erasure.scala
@@ -98,7 +98,7 @@ abstract class Erasure extends AddInterfaces
     val len = sig.length
     val copy: Array[Char] = sig.toCharArray
     var changed = false
-    while (i < sig.length) {
+    while (i < len) {
       val ch = copy(i)
       if (ch == '.' && last != '>') {
          copy(i) = '$'
@@ -410,7 +410,6 @@ abstract class Erasure extends AddInterfaces
       def fulldef(sym: Symbol) =
         if (sym == NoSymbol) sym.toString
         else s"$sym: ${sym.tpe} in ${sym.owner}"
-      var noclash = true
       val clashErrors = mutable.Buffer[(Position, String)]()
       def clashError(what: String) = {
         val pos = if (member.owner == root) member.pos else root.pos
diff --git a/src/compiler/scala/tools/nsc/transform/patmat/ScalacPatternExpanders.scala b/src/compiler/scala/tools/nsc/transform/patmat/ScalacPatternExpanders.scala
index 79f5e3bee8..407fde29a4 100644
--- a/src/compiler/scala/tools/nsc/transform/patmat/ScalacPatternExpanders.scala
+++ b/src/compiler/scala/tools/nsc/transform/patmat/ScalacPatternExpanders.scala
@@ -124,7 +124,6 @@ trait ScalacPatternExpanders {
         case _             => sel
       }
       val patterns  = newPatterns(args)
-      val isSeq = sel.symbol.name == nme.unapplySeq
       val isUnapply = sel.symbol.name == nme.unapply
       val extractor = sel.symbol.name match {
         case nme.unapply    => unapplyMethodTypes(fn.tpe, isSeq = false)
diff --git a/src/compiler/scala/tools/nsc/typechecker/Tags.scala b/src/compiler/scala/tools/nsc/typechecker/Tags.scala
index 90ec3a89b8..57dc74d2a0 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Tags.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Tags.scala
@@ -11,7 +11,6 @@ trait Tags {
     self: Typer =>
 
     private val runDefinitions = currentRun.runDefinitions
-    import runDefinitions._
 
     private def resolveTag(pos: Position, taggedTp: Type, allowMaterialization: Boolean) = enteringTyper {
       def wrapper (tree: => Tree): Tree = if (allowMaterialization) (context.withMacrosEnabled[Tree](tree)) else (context.withMacrosDisabled[Tree](tree))
@@ -66,7 +65,7 @@ trait Tags {
       // if someone requests a type tag, but scala-reflect.jar isn't on the library classpath, then bail
       if (pre == NoType && ApiUniverseClass == NoSymbol) EmptyTree
       else {
-        val tagSym = if (concrete) TypeTagClass else WeakTypeTagClass
+        val tagSym = if (concrete) runDefinitions.TypeTagClass else runDefinitions.WeakTypeTagClass
         val tagTp =  if (pre == NoType) TypeRef(ApiUniverseClass.toTypeConstructor, tagSym, List(tp)) else singleType(pre, pre member tagSym.name)
         val taggedTp = appliedType(tagTp, List(tp))
         resolveTag(pos, taggedTp, allowMaterialization)
diff --git a/src/compiler/scala/tools/nsc/typechecker/TypeDiagnostics.scala b/src/compiler/scala/tools/nsc/typechecker/TypeDiagnostics.scala
index 1dac27639c..0f90c6a478 100644
--- a/src/compiler/scala/tools/nsc/typechecker/TypeDiagnostics.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/TypeDiagnostics.scala
@@ -607,7 +607,7 @@ trait TypeDiagnostics {
           if (!c.owner.exists || c.owner.isClass || c.owner.isMethod || (c.owner.isType && !c.owner.isParameter)) c
           else enclClassOrMethodOrTypeMember(c.outer)
 
-        val tt = tparams.filter(_.name != typeNames.WILDCARD).foreach { tp =>
+        tparams.filter(_.name != typeNames.WILDCARD).foreach { tp =>
         // we don't care about type params shadowing other type params in the same declaration
         enclClassOrMethodOrTypeMember(context).outer.lookupSymbol(tp.name, s => s != tp.symbol && s.hasRawInfo && reallyExists(s)) match {
           case LookupSucceeded(_, sym2) => context.warning(tp.pos,
diff --git a/src/library/scala/collection/immutable/List.scala b/src/library/scala/collection/immutable/List.scala
index aa9dec2761..9bfefc3de2 100644
--- a/src/library/scala/collection/immutable/List.scala
+++ b/src/library/scala/collection/immutable/List.scala
@@ -290,7 +290,6 @@ sealed abstract class List[+A] extends AbstractSeq[A]
       if (this eq Nil) Nil.asInstanceOf[That] else {
         var rest = this
         var h: ::[B] = null
-        var x: A = null.asInstanceOf[A]
         // Special case for first element
         do {
           val x: Any = pf.applyOrElse(rest.head, List.partialNotApplied)
diff --git a/src/library/scala/collection/mutable/AnyRefMap.scala b/src/library/scala/collection/mutable/AnyRefMap.scala
index 47fb66744e..fccc9d83e6 100644
--- a/src/library/scala/collection/mutable/AnyRefMap.scala
+++ b/src/library/scala/collection/mutable/AnyRefMap.scala
@@ -224,7 +224,7 @@ extends AbstractMap[K, V]
   override def put(key: K, value: V): Option[V] = {
     val h = hashOf(key)
     val k = key
-    var i = seekEntryOrOpen(h, k)
+    val i = seekEntryOrOpen(h, k)
     if (i < 0) {
       val j = i & IndexMask
       _hashes(j) = h
@@ -251,7 +251,7 @@ extends AbstractMap[K, V]
   override def update(key: K, value: V): Unit = {
     val h = hashOf(key)
     val k = key
-    var i = seekEntryOrOpen(h, k)
+    val i = seekEntryOrOpen(h, k)
     if (i < 0) {
       val j = i & IndexMask
       _hashes(j) = h
diff --git a/src/library/scala/collection/mutable/LongMap.scala b/src/library/scala/collection/mutable/LongMap.scala
index ef488a3697..5fafe23d9f 100644
--- a/src/library/scala/collection/mutable/LongMap.scala
+++ b/src/library/scala/collection/mutable/LongMap.scala
@@ -81,7 +81,7 @@ extends AbstractMap[Long, V]
   private def toIndex(k: Long): Int = {
     // Part of the MurmurHash3 32 bit finalizer
     val h = ((k ^ (k >>> 32)) & 0xFFFFFFFFL).toInt
-    var x = (h ^ (h >>> 16)) * 0x85EBCA6B
+    val x = (h ^ (h >>> 16)) * 0x85EBCA6B
     (x ^ (x >>> 13)) & mask
   }
   
@@ -311,7 +311,7 @@ extends AbstractMap[Long, V]
       }
     }
     else {
-      var i = seekEntryOrOpen(key)
+      val i = seekEntryOrOpen(key)
       if (i < 0) {
         val j = i & IndexMask
         _keys(j) = key