diff options
| -rw-r--r-- | src/compiler/scala/tools/nsc/transform/TailCalls.scala | 20 |
1 files changed, 15 insertions, 5 deletions
diff --git a/src/compiler/scala/tools/nsc/transform/TailCalls.scala b/src/compiler/scala/tools/nsc/transform/TailCalls.scala index 8c582b1756..3c174d9b97 100644 --- a/src/compiler/scala/tools/nsc/transform/TailCalls.scala +++ b/src/compiler/scala/tools/nsc/transform/TailCalls.scala @@ -236,7 +236,7 @@ abstract class TailCalls extends Transform case Return(expr) => super.transform(tree) case Try(block, catches, finalizer) => - // no calls inside try are in tail position, but keep recursing for more nested functions + // no calls inside a try are in tail position, but keep recursing for nested functions copy.Try(tree, transform(block, mkContext(ctx, false)), transformTrees(catches, mkContext(ctx, false)).asInstanceOf[List[CaseDef]], transform(finalizer, mkContext(ctx, false))) @@ -252,7 +252,12 @@ abstract class TailCalls extends Transform isSameTypes(ctx.tparams, targs map (_.tpe.typeSymbol)) && isRecursiveCall(fun)) { fun match { - case Select(receiver, _) => if (!forMSIL) rewriteTailCall(fun, receiver :: transformTrees(vargs, mkContext(ctx, false))) else defaultTree + case Select(receiver, _) => + // make sure the type of 'this' doesn't change through this recursive call + if (!forMSIL && (receiver.tpe.widen == ctx.currentMethod.enclClass.typeOfThis)) + rewriteTailCall(fun, receiver :: transformTrees(vargs, mkContext(ctx, false))) + else + defaultTree case _ => rewriteTailCall(fun, This(currentClass) :: transformTrees(vargs, mkContext(ctx, false))) } } else @@ -271,7 +276,11 @@ abstract class TailCalls extends Transform ctx.tailPos && isRecursiveCall(fun)) { fun match { - case Select(receiver, _) => if (!forMSIL) rewriteTailCall(fun, receiver :: transformTrees(args, mkContext(ctx, false))) else defaultTree + case Select(receiver, _) => + if (!forMSIL) + rewriteTailCall(fun, receiver :: transformTrees(args, mkContext(ctx, false))) + else + defaultTree case _ => rewriteTailCall(fun, This(currentClass) :: transformTrees(args, mkContext(ctx, false))) } } else @@ -303,8 +312,9 @@ abstract class TailCalls extends Transform (fun.pos)) ctx.accessed = true //println("fun: " + fun + " args: " + args) - typed(atPos(fun.pos)( - Apply(Ident(ctx.label), args))) + val t = atPos(fun.pos)(Apply(Ident(ctx.label), args)) + //println(t) + typed(t) } private def isSameTypes(ts1: List[Symbol], ts2: List[Symbol]): Boolean = { |