Fixed type unsoundness problem in t5120 and als...

Fixed type unsoundness problem in t5120 and also discovered by
roman.kalukiewicz@gmail.com. Fix should be refined further, as I am not
convinced we are quite done yet. Review by moors.

1 files changed, 29 insertions, 0 deletions

diff --git a/test/files/neg/t5120.scala b/test/files/neg/t5120.scala
new file mode 100644
index 0000000000..f28b2cfb4f
--- /dev/null
+++ b/test/files/neg/t5120.scala
@@ -0,0 +1,29 @@
+class Cell[T](x0: T) {
+  type U = T
+  var x1: U = x0
+}
+
+object Test {
+  val str: Cell[String] = new Cell("a")
+  val other: Cell[Int]  = new Cell(0)
+
+  def main(args: Array[String]): Unit = {
+    List(str, other) foreach (_.x1 = new AnyRef)
+    str.x1.length
+  }
+}
+// another way demonstrating the same underlying problem, as reported by roman kalukiewicz
+
+class Holder[_T](_f1 : _T, _f2 : _T) {
+  type T = _T
+  var f1 : T = _f1
+  var f2 : T = _f2
+}
+object Test2 {
+  val str = new Holder("t1", "t2")
+  val num = new Holder(1, 2)
+  List(str, num).foreach(h => h.f1 = new Thread())
+  def main(args: Array[String]) {
+    println(str.f1)
+  }
+}