Silencing spurious MSVC C4189 warnings regarding local variables that are initialized but not used; NFC. This bug has been reported to Microsoft (https://connect.microsoft.com/VisualStudio/feedback/details/1475983).

llvm-svn: 240786
diff --git a/llvm/tools/dsymutil/DwarfLinker.cpp b/llvm/tools/dsymutil/DwarfLinker.cpp
index 7879e83..15c86e1 100644
--- a/llvm/tools/dsymutil/DwarfLinker.cpp
+++ b/llvm/tools/dsymutil/DwarfLinker.cpp
@@ -1427,10 +1427,10 @@
   ValidRelocs.clear();
   Ranges.clear();
 
-  for (auto *Block : DIEBlocks)
-    Block->~DIEBlock();
-  for (auto *Loc : DIELocs)
-    Loc->~DIELoc();
+  for (auto I = DIEBlocks.begin(), E = DIEBlocks.end(); I != E; ++I)
+    (*I)->~DIEBlock();
+  for (auto I = DIELocs.begin(), E = DIELocs.end(); I != E; ++I)
+    (*I)->~DIELoc();
 
   DIEBlocks.clear();
   DIELocs.clear();