From f274aaa8111979fd505d5c7338ce3882e8860fe9 Mon Sep 17 00:00:00 2001
From: Dale Wijnand <dale.wijnand@gmail.com>
Date: Mon, 4 Dec 2017 16:04:20 +0000
Subject: [PATCH] Remove all warnings from taskProj

---
 tasks/src/main/scala/sbt/Execute.scala | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/tasks/src/main/scala/sbt/Execute.scala b/tasks/src/main/scala/sbt/Execute.scala
index 267a1383a..bba13f448 100644
--- a/tasks/src/main/scala/sbt/Execute.scala
+++ b/tasks/src/main/scala/sbt/Execute.scala
@@ -360,8 +360,11 @@ private[sbt] final class Execute[A[_] <: AnyRef](
   // cyclic reference checking
 
   def snapshotCycleCheck(): Unit =
-    for ((called: A[c], callers) <- callers.toSeq; caller <- callers)
-      cycleCheck(caller.asInstanceOf[A[c]], called)
+    callers.toSeq foreach {
+      case (called: A[c], callers) =>
+        for (caller <- callers) cycleCheck(caller.asInstanceOf[A[c]], called)
+      case _ => ()
+    }
 
   def cycleCheck[T](node: A[T], target: A[T]): Unit = {
     if (node eq target) cyclic(node, target, "Cannot call self")