Merge pull request #1716 from paulp/merge-2.10

Merged 2.10.0/x into master.

21 files changed, 188 insertions, 131 deletions

diff --git a/src/compiler/scala/reflect/reify/Errors.scala b/src/compiler/scala/reflect/reify/Errors.scala
index 0ff098e1da..3a68794c97 100644
--- a/src/compiler/scala/reflect/reify/Errors.scala
+++ b/src/compiler/scala/reflect/reify/Errors.scala
@@ -27,10 +27,10 @@ trait Errors {
   }
 
   def CannotConvertManifestToTagWithoutScalaReflect(tpe: Type, manifestInScope: Tree) = {
-    val msg = s"""
-      |to create a type tag here, it is necessary to interoperate with the manifest `$manifestInScope` in scope.
-      |however manifest -> typetag conversion requires Scala reflection, which is not present on the classpath.
-      |to proceed put scala-reflect.jar on your compilation classpath and recompile.""".trim.stripMargin
+    val msg =
+      sm"""to create a type tag here, it is necessary to interoperate with the manifest `$manifestInScope` in scope.
+          |however manifest -> typetag conversion requires Scala reflection, which is not present on the classpath.
+          |to proceed put scala-reflect.jar on your compilation classpath and recompile."""
     throw new ReificationException(defaultErrorPosition, msg)
   }
 
diff --git a/src/compiler/scala/tools/nsc/ast/Trees.scala b/src/compiler/scala/tools/nsc/ast/Trees.scala
index c78c40dcd3..e796258967 100644
--- a/src/compiler/scala/tools/nsc/ast/Trees.scala
+++ b/src/compiler/scala/tools/nsc/ast/Trees.scala
@@ -56,7 +56,7 @@ trait Trees extends scala.reflect.internal.Trees { self: Global =>
    *  The class `C` is stored as a tree attachment.
    */
   case class InjectDerivedValue(arg: Tree)
-       extends SymTree
+       extends SymTree with TermTree
 
   class PostfixSelect(qual: Tree, name: Name) extends Select(qual, name)
 
diff --git a/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala b/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala
index f430f1fc34..9bb7e1c3df 100644
--- a/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala
+++ b/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala
@@ -1898,7 +1898,7 @@ self =>
               case _ =>
             }
             val typeAppliedTree = in.token match {
-              case LBRACKET   => atPos(start, in.offset)(TypeApply(convertToTypeId(t), typeArgs()))
+              case LBRACKET   => atPos(start, in.offset)(AppliedTypeTree(convertToTypeId(t), typeArgs()))
               case _          => t
             }
             in.token match {
diff --git a/src/compiler/scala/tools/nsc/transform/Erasure.scala b/src/compiler/scala/tools/nsc/transform/Erasure.scala
index cfc3d0a377..ba799f9186 100644
--- a/src/compiler/scala/tools/nsc/transform/Erasure.scala
+++ b/src/compiler/scala/tools/nsc/transform/Erasure.scala
@@ -437,19 +437,19 @@ abstract class Erasure extends AddInterfaces
         noclash = false
         unit.error(
           if (member.owner == root) member.pos else root.pos,
-          s"""bridge generated for member ${fulldef(member)}
-             |which overrides ${fulldef(other)}
-             |clashes with definition of $what;
-             |both have erased type ${exitingPostErasure(bridge.tpe)}""".stripMargin)
+          sm"""bridge generated for member ${fulldef(member)}
+              |which overrides ${fulldef(other)}
+              |clashes with definition of $what;
+              |both have erased type ${exitingPostErasure(bridge.tpe)}""")
       }
       for (bc <- root.baseClasses) {
         if (settings.debug.value)
           exitingPostErasure(println(
-            s"""check bridge overrides in $bc
-            ${bc.info.nonPrivateDecl(bridge.name)}
-            ${site.memberType(bridge)}
-            ${site.memberType(bc.info.nonPrivateDecl(bridge.name) orElse IntClass)}
-            ${(bridge.matchingSymbol(bc, site))}""".stripMargin))
+            sm"""check bridge overrides in $bc
+                |${bc.info.nonPrivateDecl(bridge.name)}
+                |${site.memberType(bridge)}
+                |${site.memberType(bc.info.nonPrivateDecl(bridge.name) orElse IntClass)}
+                |${(bridge.matchingSymbol(bc, site))}"""))
 
         def overriddenBy(sym: Symbol) =
           sym.matchingSymbol(bc, site).alternatives filter (sym => !sym.isBridge)
@@ -693,7 +693,7 @@ abstract class Erasure extends AddInterfaces
         adaptToType(unbox(tree, pt), pt)
       else if (isPrimitiveValueType(tree.tpe) && !isPrimitiveValueType(pt)) {
         adaptToType(box(tree, pt.toString), pt)
-      } else if (tree.tpe.isInstanceOf[MethodType] && tree.tpe.params.isEmpty) {
+      } else if (isMethodTypeWithEmptyParams(tree.tpe)) {
         // [H] this assert fails when trying to typecheck tree !(SomeClass.this.bitmap) for single lazy val
         //assert(tree.symbol.isStable, "adapt "+tree+":"+tree.tpe+" to "+pt)
         adaptToType(Apply(tree, List()) setPos tree.pos setType tree.tpe.resultType, pt)
@@ -774,16 +774,21 @@ abstract class Erasure extends AddInterfaces
             else if (!isPrimitiveValueType(qual1.tpe) && isPrimitiveValueMember(tree.symbol))
               qual1 = unbox(qual1, tree.symbol.owner.tpe)
 
-            if (isPrimitiveValueMember(tree.symbol) && !isPrimitiveValueType(qual1.tpe))
+            def selectFrom(qual: Tree) = treeCopy.Select(tree, qual, name)
+
+            if (isPrimitiveValueMember(tree.symbol) && !isPrimitiveValueType(qual1.tpe)) {
               tree.symbol = NoSymbol
-            else if (qual1.tpe.isInstanceOf[MethodType] && qual1.tpe.params.isEmpty) {
+              selectFrom(qual1)
+            } else if (isMethodTypeWithEmptyParams(qual1.tpe)) {
               assert(qual1.symbol.isStable, qual1.symbol);
-              qual1 = Apply(qual1, List()) setPos qual1.pos setType qual1.tpe.resultType
+              val applied = Apply(qual1, List()) setPos qual1.pos setType qual1.tpe.resultType
+              adaptMember(selectFrom(applied))
             } else if (!(qual1.isInstanceOf[Super] || (qual1.tpe.typeSymbol isSubClass tree.symbol.owner))) {
               assert(tree.symbol.owner != ArrayClass)
-              qual1 = cast(qual1, tree.symbol.owner.tpe)
+              selectFrom(cast(qual1, tree.symbol.owner.tpe))
+            } else {
+              selectFrom(qual1)
             }
-            treeCopy.Select(tree, qual1, name)
           }
         case SelectFromArray(qual, name, erasure) =>
           var qual1 = typedQualifier(qual)
@@ -861,6 +866,11 @@ abstract class Erasure extends AddInterfaces
           tree1
       }
     }
+
+    private def isMethodTypeWithEmptyParams(tpe: Type) = tpe match {
+      case MethodType(Nil, _) => true
+      case _                  => false
+    }
   }
 
   /** The erasure transformer */
diff --git a/src/compiler/scala/tools/nsc/transform/UnCurry.scala b/src/compiler/scala/tools/nsc/transform/UnCurry.scala
index 4f889a1d86..8ae9490dbe 100644
--- a/src/compiler/scala/tools/nsc/transform/UnCurry.scala
+++ b/src/compiler/scala/tools/nsc/transform/UnCurry.scala
@@ -371,7 +371,7 @@ abstract class UnCurry extends InfoTransform
       }
 
       val isDefinedAtMethodDef = {
-        val methSym = anonClass.newMethod(nme.isDefinedAt, fun.pos, FINAL)
+        val methSym = anonClass.newMethod(nme.isDefinedAt, fun.pos, FINAL | SYNTHETIC)
         val params  = methSym newSyntheticValueParams formals
         methSym setInfoAndEnter MethodType(params, BooleanClass.tpe)
 
diff --git a/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala b/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala
index bfc9f08553..a6d11f13d4 100644
--- a/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala
@@ -106,9 +106,9 @@ trait ContextErrors {
         s"$name extends Any, not AnyRef"
     )
     if (isPrimitiveValueType(found) || isTrivialTopType(tp)) "" else "\n" +
-       s"""|Note that $what.
-           |Such types can participate in value classes, but instances
-           |cannot appear in singleton types or in reference comparisons.""".stripMargin
+       sm"""|Note that $what.
+            |Such types can participate in value classes, but instances
+            |cannot appear in singleton types or in reference comparisons."""
   }
 
   import ErrorUtils._
@@ -1125,9 +1125,9 @@ trait ContextErrors {
                                (isView: Boolean, pt: Type, tree: Tree)(implicit context0: Context) = {
       if (!info1.tpe.isErroneous && !info2.tpe.isErroneous) {
         def coreMsg =
-           s"""| $pre1 ${info1.sym.fullLocationString} of type ${info1.tpe}
-               | $pre2 ${info2.sym.fullLocationString} of type ${info2.tpe}
-               | $trailer""".stripMargin
+           sm"""| $pre1 ${info1.sym.fullLocationString} of type ${info1.tpe}
+                | $pre2 ${info2.sym.fullLocationString} of type ${info2.tpe}
+                | $trailer"""
         def viewMsg = {
           val found :: req :: _ = pt.typeArgs
           def explanation = {
@@ -1138,19 +1138,19 @@ trait ContextErrors {
             // involving Any, are further explained from foundReqMsg.
             if (AnyRefClass.tpe <:< req) (
               if (sym == AnyClass || sym == UnitClass) (
-                 s"""|Note: ${sym.name} is not implicitly converted to AnyRef.  You can safely
-                     |pattern match `x: AnyRef` or cast `x.asInstanceOf[AnyRef]` to do so.""".stripMargin
+                 sm"""|Note: ${sym.name} is not implicitly converted to AnyRef.  You can safely
+                      |pattern match `x: AnyRef` or cast `x.asInstanceOf[AnyRef]` to do so."""
               )
               else boxedClass get sym map (boxed =>
-                 s"""|Note: an implicit exists from ${sym.fullName} => ${boxed.fullName}, but
-                     |methods inherited from Object are rendered ambiguous.  This is to avoid
-                     |a blanket implicit which would convert any ${sym.fullName} to any AnyRef.
-                     |You may wish to use a type ascription: `x: ${boxed.fullName}`.""".stripMargin
+                 sm"""|Note: an implicit exists from ${sym.fullName} => ${boxed.fullName}, but
+                      |methods inherited from Object are rendered ambiguous.  This is to avoid
+                      |a blanket implicit which would convert any ${sym.fullName} to any AnyRef.
+                      |You may wish to use a type ascription: `x: ${boxed.fullName}`."""
               ) getOrElse ""
             )
             else
-               s"""|Note that implicit conversions are not applicable because they are ambiguous:
-                   |${coreMsg}are possible conversion functions from $found to $req""".stripMargin
+               sm"""|Note that implicit conversions are not applicable because they are ambiguous:
+                    |${coreMsg}are possible conversion functions from $found to $req"""
           }
           typeErrorMsg(found, req, infer.isPossiblyMissingArgs(found, req)) + (
             if (explanation == "") "" else "\n" + explanation
diff --git a/src/compiler/scala/tools/nsc/typechecker/Implicits.scala b/src/compiler/scala/tools/nsc/typechecker/Implicits.scala
index eb45f9b847..739e28bf0c 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Implicits.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Implicits.scala
@@ -1298,17 +1298,17 @@ trait Implicits {
         else {
           if (ReflectRuntimeUniverse == NoSymbol) {
             // todo. write a test for this
-            context.error(pos, s"""
-              |to create a manifest here, it is necessary to interoperate with the type tag `$tagInScope` in scope.
-              |however typetag -> manifest conversion requires Scala reflection, which is not present on the classpath.
-              |to proceed put scala-reflect.jar on your compilation classpath and recompile.""".trim.stripMargin)
+            context.error(pos,
+              sm"""to create a manifest here, it is necessary to interoperate with the type tag `$tagInScope` in scope.
+                  |however typetag -> manifest conversion requires Scala reflection, which is not present on the classpath.
+                  |to proceed put scala-reflect.jar on your compilation classpath and recompile.""")
             return SearchFailure
           }
           if (resolveClassTag(pos, tp, allowMaterialization = true) == EmptyTree) {
-            context.error(pos, s"""
-              |to create a manifest here, it is necessary to interoperate with the type tag `$tagInScope` in scope.
-              |however typetag -> manifest conversion requires a class tag for the corresponding type to be present.
-              |to proceed add a class tag to the type `$tp` (e.g. by introducing a context bound) and recompile.""".trim.stripMargin)
+            context.error(pos,
+              sm"""to create a manifest here, it is necessary to interoperate with the type tag `$tagInScope` in scope.
+                  |however typetag -> manifest conversion requires a class tag for the corresponding type to be present.
+                  |to proceed add a class tag to the type `$tp` (e.g. by introducing a context bound) and recompile.""")
             return SearchFailure
           }
           val cm = typed(Ident(ReflectRuntimeCurrentMirror))
diff --git a/src/compiler/scala/tools/nsc/typechecker/Macros.scala b/src/compiler/scala/tools/nsc/typechecker/Macros.scala
index 4b534b0d2e..e40d978e6d 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Macros.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Macros.scala
@@ -117,16 +117,9 @@ trait Macros extends scala.tools.reflect.FastTrack with Traces {
       }
 
     def pickle(macroImplRef: Tree): Tree = {
-      val macroImpl = macroImplRef.symbol
+      val MacroImplReference(owner, macroImpl, targs) = macroImplRef
       val paramss = macroImpl.paramss
 
-      // this logic relies on the assumptions that were valid for the old macro prototype
-      // namely that macro implementations can only be defined in top-level classes and modules
-      // with the new prototype that materialized in a SIP, macros need to be statically accessible, which is different
-      // for example, a macro def could be defined in a trait that is implemented by an object
-      // there are some more clever cases when seemingly non-static method ends up being statically accessible
-      // however, the code below doesn't account for these guys, because it'd take a look of time to get it right
-      // for now I leave it as a todo and move along to more the important stuff
       // todo. refactor when fixing SI-5498
       def className: String = {
         def loop(sym: Symbol): String = sym match {
@@ -138,7 +131,7 @@ trait Macros extends scala.tools.reflect.FastTrack with Traces {
             loop(sym.owner) + separator + sym.javaSimpleName.toString
         }
 
-        loop(macroImpl.owner.enclClass)
+        loop(owner)
       }
 
       def signature: List[Int] = {
@@ -159,7 +152,7 @@ trait Macros extends scala.tools.reflect.FastTrack with Traces {
       // I just named it "macro", because it's macro-related, but I could as well name it "foobar"
       val nucleus = Ident(newTermName("macro"))
       val wrapped = Apply(nucleus, payload map { case (k, v) => Assign(pickleAtom(k), pickleAtom(v)) })
-      val pickle = gen.mkTypeApply(wrapped, treeInfo.typeArguments(macroImplRef.duplicate))
+      val pickle = gen.mkTypeApply(wrapped, targs map (_.duplicate))
 
       // assign NoType to all freshly created AST nodes
       // otherwise pickler will choke on tree.tpe being null
diff --git a/src/compiler/scala/tools/nsc/typechecker/PatternMatching.scala b/src/compiler/scala/tools/nsc/typechecker/PatternMatching.scala
index c5245c4e9e..42c34526d7 100644
--- a/src/compiler/scala/tools/nsc/typechecker/PatternMatching.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/PatternMatching.scala
@@ -1151,7 +1151,7 @@ trait PatternMatching extends Transform with TypingTransformers with ast.TreeDSL
 
           // ExplicitOuter replaces `Select(q, outerSym) OBJ_EQ expectedPrefix` by `Select(q, outerAccessor(outerSym.owner)) OBJ_EQ expectedPrefix`
           // if there's an outer accessor, otherwise the condition becomes `true` -- TODO: can we improve needsOuterTest so there's always an outerAccessor?
-          val outer = expectedTp.typeSymbol.newMethod(vpmName.outer) setInfo expectedTp.prefix setFlag SYNTHETIC | ARTIFACT
+          val outer = expectedTp.typeSymbol.newMethod(vpmName.outer, newFlags = SYNTHETIC | ARTIFACT) setInfo expectedTp.prefix
 
           (Select(codegen._asInstanceOf(testedBinder, expectedTp), outer)) OBJ_EQ expectedOuter
         }
@@ -1413,7 +1413,7 @@ trait PatternMatching extends Transform with TypingTransformers with ast.TreeDSL
 
     // assert(owner ne null); assert(owner ne NoSymbol)
     def freshSym(pos: Position, tp: Type = NoType, prefix: String = "x") =
-      NoSymbol.newTermSymbol(freshName(prefix), pos) setInfo tp
+      NoSymbol.newTermSymbol(freshName(prefix), pos, newFlags = SYNTHETIC) setInfo tp
 
     def newSynthCaseLabel(name: String) =
       NoSymbol.newLabel(freshName(name), NoPosition) setFlag treeInfo.SYNTH_CASE_FLAGS
@@ -3600,7 +3600,7 @@ trait PatternMatching extends Transform with TypingTransformers with ast.TreeDSL
        */
       def matcher(scrut: Tree, scrutSym: Symbol, restpe: Type)(cases: List[Casegen => Tree], matchFailGen: Option[Tree => Tree]): Tree = {
         val matchEnd = newSynthCaseLabel("matchEnd")
-        val matchRes = NoSymbol.newValueParameter(newTermName("x"), NoPosition, SYNTHETIC) setInfo restpe.withoutAnnotations
+        val matchRes = NoSymbol.newValueParameter(newTermName("x"), NoPosition, newFlags = SYNTHETIC) setInfo restpe.withoutAnnotations
         matchEnd setInfo MethodType(List(matchRes), restpe)
 
         def newCaseSym = newSynthCaseLabel("case") setInfo MethodType(Nil, restpe)
diff --git a/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala b/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala
index 7a7c7c7d25..0ae225ccee 100644
--- a/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala
@@ -1382,8 +1382,8 @@ abstract class RefChecks extends InfoTransform with scala.reflect.internal.trans
     private def checkCompileTimeOnly(sym: Symbol, pos: Position) = {
       if (sym.isCompileTimeOnly) {
         def defaultMsg =
-          s"""|Reference to ${sym.fullLocationString} should not have survived past type checking,
-              |it should have been processed and eliminated during expansion of an enclosing macro.""".stripMargin
+          sm"""Reference to ${sym.fullLocationString} should not have survived past type checking,
+              |it should have been processed and eliminated during expansion of an enclosing macro."""
         // The getOrElse part should never happen, it's just here as a backstop.
         unit.error(pos, sym.compileTimeOnlyMessage getOrElse defaultMsg)
       }
diff --git a/src/compiler/scala/tools/nsc/typechecker/SuperAccessors.scala b/src/compiler/scala/tools/nsc/typechecker/SuperAccessors.scala
index 5fb9a5e67e..0992cd7955 100644
--- a/src/compiler/scala/tools/nsc/typechecker/SuperAccessors.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/SuperAccessors.scala
@@ -525,8 +525,8 @@ abstract class SuperAccessors extends transform.Transform with transform.TypingT
       }
       def isJavaProtected = host.isTrait && sym.isJavaDefined && {
         restrictionError(pos, unit,
-          s"""|$clazz accesses protected $sym inside a concrete trait method.
-              |Add an accessor in a class extending ${sym.enclClass} as a workaround.""".stripMargin
+          sm"""$clazz accesses protected $sym inside a concrete trait method.
+              |Add an accessor in a class extending ${sym.enclClass} as a workaround."""
         )
         true
       }
diff --git a/src/compiler/scala/tools/nsc/typechecker/TreeCheckers.scala b/src/compiler/scala/tools/nsc/typechecker/TreeCheckers.scala
index be7554abe2..fb95c952d2 100644
--- a/src/compiler/scala/tools/nsc/typechecker/TreeCheckers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/TreeCheckers.scala
@@ -268,11 +268,9 @@ abstract class TreeCheckers extends Analyzer {
               if (sym.owner != currentOwner) {
                 val expected = currentOwner.ownerChain find (x => cond(x)) getOrElse { fail("DefTree can't find owner: ") ; NoSymbol }
                 if (sym.owner != expected)
-                  fail("""|
-                          | currentOwner chain: %s
-                          |       symbol chain: %s""".stripMargin.format(
-                            currentOwner.ownerChain take 3 mkString " -> ",
-                            sym.ownerChain mkString " -> ")
+                  fail(sm"""|
+                            | currentOwner chain: ${currentOwner.ownerChain take 3 mkString " -> "}
+                            |       symbol chain: ${sym.ownerChain mkString " -> "}"""
                       )
               }
           }
diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
index 42c7d4a6b8..e534e36a0d 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
@@ -3763,54 +3763,45 @@ trait Typers extends Modes with Adaptations with Tags {
        *
        */
       def mkInvoke(cxTree: Tree, tree: Tree, qual: Tree, name: Name): Option[Tree] = {
-        debuglog(s"dyna.mkInvoke($cxTree, $tree, $qual, $name)")
+        log(s"dyna.mkInvoke($cxTree, $tree, $qual, $name)")
+        val treeSelection = treeInfo.methPart(tree)
+        def isDesugaredApply = treeSelection match {
+          case Select(`qual`, nme.apply) => true
+          case _                         => false
+        }
         acceptsApplyDynamicWithType(qual, name) map { tp =>
-          // tp eq NoType => can call xxxDynamic, but not passing any type args (unless specified explicitly by the user)
-          // in scala-virtualized, when not NoType, tp is passed as type argument (for selection on a staged Struct)
-
-          // strip off type application -- we're not doing much with outer,
-          // so don't bother preserving cxTree's attributes etc
-          val cxTree1 = cxTree match {
-            case t: ValOrDefDef => t.rhs
-            case t              => t
-          }
-          val cxTree2 = cxTree1 match {
-            case Typed(t, tpe)  => t // ignore outer type annotation
-            case t              => t
-          }
-          val (outer, explicitTargs) = cxTree2 match {
-            case TypeApply(fun, targs)              => (fun, targs)
-            case Apply(TypeApply(fun, targs), args) => (Apply(fun, args), targs)
-            case Select(TypeApply(fun, targs), nme) => (Select(fun, nme), targs)
-            case t                                  => (t, Nil)
-          }
-          def hasNamedArg(as: List[Tree]) = as.collectFirst{case AssignOrNamedArg(lhs, rhs) =>}.nonEmpty
-
-          def desugaredApply = tree match {
-            case Select(`qual`, nme.apply) => true
-            case _ => false
+          // If tp == NoType, pass only explicit type arguments to applyXXX.  Not used at all
+          // here - it is for scala-virtualized, where tp will be passed as an argument (for
+          // selection on a staged Struct)
+          def hasNamed(args: List[Tree]): Boolean = args exists (_.isInstanceOf[AssignOrNamedArg])
+          // not supported: foo.bar(a1,..., an: _*)
+          def hasStar(args: List[Tree]) = treeInfo.isWildcardStarArgList(args)
+          def applyOp(args: List[Tree]) = if (hasNamed(args)) nme.applyDynamicNamed else nme.applyDynamic
+          def matches(t: Tree)          = isDesugaredApply || treeInfo.methPart(t) == treeSelection
+
+          /** Note that the trees which arrive here are potentially some distance from
+           *  the trees of direct interest. `cxTree` is some enclosing expression which
+           *  may apparently be arbitrarily larger than `tree`; and `tree` itself is
+           *  too small, having at least in some cases lost its explicit type parameters.
+           *  This logic is designed to use `tree` to pinpoint the immediately surrounding
+           *  Apply/TypeApply/Select node, and only then creates the dynamic call.
+           *  See SI-6731 among others.
+           */
+          def findSelection(t: Tree): Option[(TermName, Tree)] = t match {
+            case Apply(fn, args) if hasStar(args) => DynamicVarArgUnsupported(tree, applyOp(args)) ; None
+            case Apply(fn, args) if matches(fn)   => Some((applyOp(args), fn))
+            case Assign(lhs, _) if matches(lhs)   => Some((nme.updateDynamic, lhs))
+            case _ if matches(t)                  => Some((nme.selectDynamic, t))
+            case _                                => t.children flatMap findSelection headOption
           }
-          // note: context.tree includes at most one Apply node
-          // thus, we can't use it to detect we're going to receive named args in expressions such as:
-          //   qual.sel(a)(a2, arg2 = "a2")
-          val oper = outer match {
-            case Apply(q, as) if q == tree || desugaredApply =>
-              val oper =
-                if (hasNamedArg(as))  nme.applyDynamicNamed
-                else                  nme.applyDynamic
-              // not supported: foo.bar(a1,..., an: _*)
-              if (treeInfo.isWildcardStarArgList(as)) {
-               DynamicVarArgUnsupported(tree, oper)
-               return Some(setError(tree))
-              } else oper
-            case Assign(`tree`, _) => nme.updateDynamic
-            case _                 => nme.selectDynamic
+          findSelection(cxTree) match {
+            case Some((opName, tapply)) =>
+              val targs = treeInfo.typeArguments(tapply)
+              val fun   = gen.mkTypeApply(Select(qual, opName), targs)
+              atPos(qual.pos)(Apply(fun, Literal(Constant(name.decode)) :: Nil))
+            case _ =>
+              setError(tree)
           }
-
-          val dynSel  = Select(qual, oper)
-          val tappSel = if (explicitTargs.nonEmpty) TypeApply(dynSel, explicitTargs) else dynSel
-
-          atPos(qual.pos)(Apply(tappSel, List(Literal(Constant(name.decode)))))
         }
       }
 
@@ -5015,7 +5006,7 @@ trait Typers extends Modes with Adaptations with Tags {
             case tt @ TypeTree() => tree setOriginal tt.original
             case _ => tree
           }
-        } 
+        }
         else
           // we should get here only when something before failed
           // and we try again (@see tryTypedApply). In that case we can assign
diff --git a/src/library/scala/Symbol.scala b/src/library/scala/Symbol.scala
index 723c05a30c..4fead7a50c 100644
--- a/src/library/scala/Symbol.scala
+++ b/src/library/scala/Symbol.scala
@@ -69,6 +69,11 @@ private[scala] abstract class UniquenessCache[K, V >: Null]
         val res = cached()
         if (res != null) res
         else {
+          // If we don't remove the old String key from the map, we can
+          // wind up with one String as the key and a different String as
+          // as the name field in the Symbol, which can lead to surprising
+          // GC behavior and duplicate Symbols. See SI-6706.
+          map remove name
           val sym = valueFromKey(name)
           map.put(name, new WeakReference(sym))
           sym
diff --git a/src/library/scala/collection/mutable/FlatHashTable.scala b/src/library/scala/collection/mutable/FlatHashTable.scala
index 94242260a1..7ab99fcda2 100644
--- a/src/library/scala/collection/mutable/FlatHashTable.scala
+++ b/src/library/scala/collection/mutable/FlatHashTable.scala
@@ -110,24 +110,23 @@ trait FlatHashTable[A] extends FlatHashTable.HashUtils[A] {
 
   /** Finds an entry in the hash table if such an element exists. */
   protected def findEntry(elem: A): Option[A] = {
-    var h = index(elemHashCode(elem))
-    var entry = table(h)
-    while (null != entry && entry != elem) {
-      h = (h + 1) % table.length
-      entry = table(h)
-    }
+    val entry = findEntryImpl(elem)
     if (null == entry) None else Some(entry.asInstanceOf[A])
   }
 
   /** Checks whether an element is contained in the hash table. */
   protected def containsEntry(elem: A): Boolean = {
+    null != findEntryImpl(elem)
+  }
+
+  private def findEntryImpl(elem: A): AnyRef = {
     var h = index(elemHashCode(elem))
     var entry = table(h)
     while (null != entry && entry != elem) {
       h = (h + 1) % table.length
       entry = table(h)
     }
-    null != entry
+    entry
   }
 
   /** Add entry if not yet in table.
diff --git a/src/reflect/scala/reflect/internal/SymbolTable.scala b/src/reflect/scala/reflect/internal/SymbolTable.scala
index a0e5851a6e..1298fc17ed 100644
--- a/src/reflect/scala/reflect/internal/SymbolTable.scala
+++ b/src/reflect/scala/reflect/internal/SymbolTable.scala
@@ -344,6 +344,11 @@ abstract class SymbolTable extends macros.Universe
   @inline final def atPhase[T](ph: Phase)(op: => T): T = enteringPhase(ph)(op)
   @deprecated("Use enteringPhaseNotLaterThan", "2.10.0")
   @inline final def atPhaseNotLaterThan[T](target: Phase)(op: => T): T = enteringPhaseNotLaterThan(target)(op)
+
+  /**
+   * Adds the `sm` String interpolator to a [[scala.StringContext]].
+   */
+  implicit val StringContextStripMarginOps: StringContext => StringContextStripMarginOps = util.StringContextStripMarginOps
 }
 
 object SymbolTableStats {
diff --git a/src/reflect/scala/reflect/internal/Symbols.scala b/src/reflect/scala/reflect/internal/Symbols.scala
index ad7dbe5ef1..7de53a7731 100644
--- a/src/reflect/scala/reflect/internal/Symbols.scala
+++ b/src/reflect/scala/reflect/internal/Symbols.scala
@@ -77,7 +77,7 @@ trait Symbols extends api.Symbols { self: SymbolTable =>
     def isImplementationArtifact: Boolean = (this hasFlag BRIDGE) || (this hasFlag VBRIDGE) || (this hasFlag ARTIFACT)
     def isJava: Boolean = isJavaDefined
     def isVal: Boolean = isTerm && !isModule && !isMethod && !isMutable
-    def isVar: Boolean = isTerm && !isModule && !isMethod && isMutable
+    def isVar: Boolean = isTerm && !isModule && !isMethod && !isLazy && isMutable
 
     def newNestedSymbol(name: Name, pos: Position, newFlags: Long, isClass: Boolean): Symbol = name match {
       case n: TermName => newTermSymbol(n, pos, newFlags)
diff --git a/src/reflect/scala/reflect/internal/Trees.scala b/src/reflect/scala/reflect/internal/Trees.scala
index f944e1d5d1..5c1d109662 100644
--- a/src/reflect/scala/reflect/internal/Trees.scala
+++ b/src/reflect/scala/reflect/internal/Trees.scala
@@ -392,6 +392,9 @@ trait Trees extends api.Trees { self: SymbolTable =>
 
   case class TypeApply(fun: Tree, args: List[Tree])
        extends GenericApply with TypeApplyApi {
+
+    assert(fun.isTerm, fun)
+
     override def symbol: Symbol = fun.symbol
     override def symbol_=(sym: Symbol) { fun.symbol = sym }
   }
@@ -437,7 +440,11 @@ trait Trees extends api.Trees { self: SymbolTable =>
   object This extends ThisExtractor
 
   case class Select(qualifier: Tree, name: Name)
-       extends RefTree with SelectApi
+       extends RefTree with SelectApi {
+
+    // !!! assert disabled due to test case pos/annotDepMethType.scala triggering it.
+    // assert(qualifier.isTerm, qualifier)
+  }
   object Select extends SelectExtractor
 
   case class Ident(name: Name) extends RefTree with IdentContextApi {
@@ -469,7 +476,10 @@ trait Trees extends api.Trees { self: SymbolTable =>
   object SingletonTypeTree extends SingletonTypeTreeExtractor
 
   case class SelectFromTypeTree(qualifier: Tree, name: TypeName)
-       extends RefTree with TypTree with SelectFromTypeTreeApi
+       extends RefTree with TypTree with SelectFromTypeTreeApi {
+
+    assert(qualifier.isType, qualifier)
+  }
   object SelectFromTypeTree extends SelectFromTypeTreeExtractor
 
   case class CompoundTypeTree(templ: Template)
@@ -478,6 +488,9 @@ trait Trees extends api.Trees { self: SymbolTable =>
 
   case class AppliedTypeTree(tpt: Tree, args: List[Tree])
        extends TypTree with AppliedTypeTreeApi {
+
+    assert(tpt.isType, tpt)
+
     override def symbol: Symbol = tpt.symbol
     override def symbol_=(sym: Symbol) { tpt.symbol = sym }
   }
diff --git a/src/reflect/scala/reflect/internal/util/StripMarginInterpolator.scala b/src/reflect/scala/reflect/internal/util/StripMarginInterpolator.scala
new file mode 100644
index 0000000000..e7579229b2
--- /dev/null
+++ b/src/reflect/scala/reflect/internal/util/StripMarginInterpolator.scala
@@ -0,0 +1,40 @@
+package scala.reflect
+package internal
+package util
+
+trait StripMarginInterpolator {
+  def stringContext: StringContext
+
+  /**
+   * A safe combination of `[[scala.collection.immutable.StringLike#stripMargin]]
+   * and [[scala.StringContext#raw]].
+   *
+   * The margin of each line is defined by whitespace leading up to a '|' character.
+   * This margin is stripped '''before''' the arguments are interpolated into to string.
+   *
+   * String escape sequences are '''not''' processed; this interpolater is designed to
+   * be used with triple quoted Strings.
+   *
+   * {{{
+   * scala> val foo = "f|o|o"
+   * foo: String = f|o|o
+   * scala> sm"""|${foo}
+   *             |"""
+   * res0: String =
+   * "f|o|o
+   * "
+   * }}}
+   */
+  final def sm(args: Any*): String = {
+    def isLineBreak(c: Char) = c == '\n' || c == '\f' // compatible with StringLike#isLineBreak
+    def stripTrailingPart(s: String) = {
+      val (pre, post) = s.span(c => !isLineBreak(c))
+      pre + post.stripMargin
+    }
+    val stripped: List[String] = stringContext.parts.toList match {
+      case head :: tail => head.stripMargin :: (tail map stripTrailingPart)
+      case Nil => Nil
+    }
+    new StringContext(stripped: _*).raw(args: _*)
+  }
+}
diff --git a/src/reflect/scala/reflect/internal/util/package.scala b/src/reflect/scala/reflect/internal/util/package.scala
index 83c8bf67ba..1ca57b81ed 100644
--- a/src/reflect/scala/reflect/internal/util/package.scala
+++ b/src/reflect/scala/reflect/internal/util/package.scala
@@ -31,4 +31,8 @@ package object util {
     }
     else shortenName(name)
   }
+  /**
+   * Adds the `sm` String interpolator to a [[scala.StringContext]].
+   */
+  implicit class StringContextStripMarginOps(val stringContext: StringContext) extends StripMarginInterpolator
 }
diff --git a/src/reflect/scala/reflect/runtime/JavaMirrors.scala b/src/reflect/scala/reflect/runtime/JavaMirrors.scala
index d264cc06b4..54d02f3371 100644
--- a/src/reflect/scala/reflect/runtime/JavaMirrors.scala
+++ b/src/reflect/scala/reflect/runtime/JavaMirrors.scala
@@ -126,11 +126,10 @@ private[reflect] trait JavaMirrors extends internal.SymbolTable with api.JavaUni
     private def ErrorStaticModule(sym: Symbol) = throw new ScalaReflectionException(s"$sym is a static module, use reflectModule on a RuntimeMirror to obtain its ModuleMirror")
     private def ErrorNotMember(sym: Symbol, owner: Symbol) = throw new ScalaReflectionException(s"expected a member of $owner, you provided ${sym.kindString} ${sym.fullName}")
     private def ErrorNotField(sym: Symbol) = throw new ScalaReflectionException(s"expected a field or an accessor method symbol, you provided $sym")
-    private def ErrorNonExistentField(sym: Symbol) = throw new ScalaReflectionException(s"""
-      |Scala field ${sym.name} isn't represented as a Java field, neither it has a Java accessor method
-      |note that private parameters of class constructors don't get mapped onto fields and/or accessors,
-      |unless they are used outside of their declaring constructors.
-    """.trim.stripMargin)
+    private def ErrorNonExistentField(sym: Symbol) = throw new ScalaReflectionException(
+      sm"""Scala field ${sym.name} isn't represented as a Java field, neither it has a Java accessor method
+          |note that private parameters of class constructors don't get mapped onto fields and/or accessors,
+          |unless they are used outside of their declaring constructors.""")
     private def ErrorSetImmutableField(sym: Symbol) = throw new ScalaReflectionException(s"cannot set an immutable field ${sym.name}")
     private def ErrorNotConstructor(sym: Symbol, owner: Symbol) = throw new ScalaReflectionException(s"expected a constructor of $owner, you provided $sym")
     private def ErrorFree(member: Symbol, freeType: Symbol) = throw new ScalaReflectionException(s"cannot reflect ${member.kindString} ${member.name}, because it's a member of a weak type ${freeType.name}")
@@ -535,8 +534,8 @@ private[reflect] trait JavaMirrors extends internal.SymbolTable with api.JavaUni
           val result = anns find (_.annotationType == annotClass)
           if (result.isEmpty && (anns exists (_.annotationType.getName == name)))
             throw new ClassNotFoundException(
-              s"""Mirror classloader mismatch: $jclazz (loaded by ${ReflectionUtils.show(jclazz.getClassLoader)})
-              |is unrelated to the mirror's classloader: (${ReflectionUtils.show(classLoader)})""".stripMargin)
+              sm"""Mirror classloader mismatch: $jclazz (loaded by ${ReflectionUtils.show(jclazz.getClassLoader)})
+                  |is unrelated to the mirror's classloader: (${ReflectionUtils.show(classLoader)})""")
           result
         }
       def loadBytes[T: ClassTag](name: String): Option[T] =
@@ -935,8 +934,8 @@ private[reflect] trait JavaMirrors extends internal.SymbolTable with api.JavaUni
             javaTypeToValueClass(jclazz) orElse lookupClass
 
         assert (cls.isType,
-          s"""${if (cls == NoSymbol) "not a type: symbol" else "no symbol could be"}
-             | loaded from $jclazz in $owner with name $simpleName and classloader $classLoader""".stripMargin)
+          sm"""${if (cls == NoSymbol) "not a type: symbol" else "no symbol could be"}
+              | loaded from $jclazz in $owner with name $simpleName and classloader $classLoader""")
 
         cls.asClass
       }