Fix memory leak related to default arguments in presentation compiler.

This bug exists for a long time, but was triggered / discovered only lately
by the default argument of mkParams in 118aef558f.

This reverts the workaroud commit 19b6ad5ee4.

The fix is tested by test/files/presentation/memory-leaks which runs the
presentation compiler several times on Typers.scala. I could not reproduce
the memory leak in a smaller test case.

1 files changed, 3 insertions, 3 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
index f558e0afc7..c9679faa7d 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
@@ -2202,7 +2202,7 @@ trait Typers extends Modes with Adaptations with PatMatVirtualiser {
             vparams map {p => if(p.tpt.tpe == null) typedType(p.tpt).tpe else p.tpt.tpe}
         }
 
-      def mkParams(methodSym: Symbol, formals: List[Type]/* = deriveFormals*/) = {
+      def mkParams(methodSym: Symbol, formals: List[Type] = deriveFormals) = {
         selOverride match {
           case None if targs.isEmpty => MissingParameterTypeAnonMatchError(tree, pt); (Nil, EmptyTree)
           case None =>
@@ -2228,7 +2228,7 @@ trait Typers extends Modes with Adaptations with PatMatVirtualiser {
         // rig the show so we can get started typing the method body -- later we'll correct the infos...
         anonClass setInfo ClassInfoType(List(ObjectClass.tpe, pt, SerializableClass.tpe), newScope, anonClass)
         val methodSym = anonClass.newMethod(nme.apply, tree.pos, FINAL)
-        val (paramSyms, selector) = mkParams(methodSym, deriveFormals)
+        val (paramSyms, selector) = mkParams(methodSym)
 
         if (selector eq EmptyTree) EmptyTree
         else {
@@ -2292,7 +2292,7 @@ trait Typers extends Modes with Adaptations with PatMatVirtualiser {
 
       def isDefinedAtMethod = {
         val methodSym = anonClass.newMethod(nme.isDefinedAt, tree.pos, FINAL)
-        val (paramSyms, selector) = mkParams(methodSym, deriveFormals)
+        val (paramSyms, selector) = mkParams(methodSym)
         if (selector eq EmptyTree) EmptyTree
         else {
           val methodBodyTyper = newTyper(context.makeNewScope(context.tree, methodSym)) // should use the DefDef for the context's tree, but it doesn't exist yet (we need the typer we're creating to create it)