1 files changed, 43 insertions, 0 deletions
diff --git a/test/files/run/t7775.scala b/test/files/run/t7775.scala
index 48b0d89974..bc69064e17 100644
--- a/test/files/run/t7775.scala
+++ b/test/files/run/t7775.scala
@@ -1,3 +1,45 @@
+import scala.concurrent._, duration._
+import ExecutionContext.Implicits.global
+import scala.tools.reflect.WrappedProperties.AccessControl._
+import java.util.concurrent.CyclicBarrier
+
+object Test extends App {
+  @volatile var done = false
+  val barrier = new CyclicBarrier(2)
+
+  val probe = Future {
+    val attempts     = 1024          // previously, failed after a few
+    def fail(i: Int) = s"Failed at $i"
+    barrier.await()
+    for (i <- 1 to attempts ; p <- systemProperties)
+      p match { case (k, v) => assert (k != null && v != null, fail(i)) }
+  }
+  probe onComplete {
+    case _ => done = true
+  }
+
+  System.setProperty("foo", "fooz")
+  System.setProperty("bar", "barz")
+  barrier.await()   // just for fun, wait to start mucking with properties
+
+  // continually modify properties trying to break live iteration over sys props
+  // hint: don't iterate lively over sys props
+  var alt = true
+  while (!done) {
+    if (alt) {
+      System.getProperties.remove("foo")
+      System.setProperty("bar", "barz")
+      alt = false
+    } else {
+      System.getProperties.remove("bar")
+      System.setProperty("foo", "fooz")
+      alt = true
+    }
+  }
+  Await.result(probe, Duration.Inf)
+}
+
+/*
 import scala.concurrent.{duration, Future, Await, ExecutionContext}
 import scala.tools.nsc.Settings
 import ExecutionContext.Implicits.global
@@ -15,3 +57,4 @@ object Test {
     Await.result(compiler, duration.Duration.Inf)
   }
 }
+*/