2 files changed, 19 insertions, 0 deletions
diff --git a/test/files/neg/t5580b.check b/test/files/neg/t5580b.check
new file mode 100644
index 0000000000..45fde46ff9
--- /dev/null
+++ b/test/files/neg/t5580b.check
@@ -0,0 +1,6 @@
+t5580b.scala:11: error: polymorphic expression cannot be instantiated to expected type;
+ found   : [A]scala.collection.mutable.Set[A]
+ required: scala.collection.mutable.Map[bar,scala.collection.mutable.Set[bar]]
+    if (map.get(tmp).isEmpty) map.put(tmp,collection.mutable.Set())
+                                                                ^
+one error found
diff --git a/test/files/neg/t5580b.scala b/test/files/neg/t5580b.scala
new file mode 100644
index 0000000000..2161da4584
--- /dev/null
+++ b/test/files/neg/t5580b.scala
@@ -0,0 +1,13 @@
+import scala.collection.mutable.WeakHashMap
+import scala.collection.JavaConversions._
+
+class bar { }
+
+class foo {
+  val map = WeakHashMap[AnyRef, collection.mutable.Map[bar, collection.mutable.Set[bar]]]()
+
+  def test={
+    val tmp:bar=null
+    if (map.get(tmp).isEmpty) map.put(tmp,collection.mutable.Set())
+  }
+}