r157525 didn't work, just disable iterator checking.

This is obviosly right but I don't see how to do this with proper vector
iterators without building a horrible mess of workarounds.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157526 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 1330a26..6837d82 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -1991,7 +1991,7 @@
     // The last case block won't fall through into 'NextBlock' if we emit the
     // branches in this order.  See if rearranging a case value would help.
     // We start at the bottom as it's the case with the least weight.
-    for (CaseItr I = CR.Range.second-2, E = CR.Range.first; I >= E; --I) {
+    for (Case *I = &*CR.Range.second-2, *E = &*CR.Range.first-1; I != E; --I){
       if (I->BB == NextBlock) {
         std::swap(*I, BackCase);
         break;