Silenced a VC++ warning.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43374 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/IPA/Andersens.cpp b/lib/Analysis/IPA/Andersens.cpp
index e20be6b..08b9dc3 100644
--- a/lib/Analysis/IPA/Andersens.cpp
+++ b/lib/Analysis/IPA/Andersens.cpp
@@ -112,7 +112,7 @@
 
   class VISIBILITY_HIDDEN Andersens : public ModulePass, public AliasAnalysis,
                                       private InstVisitor<Andersens> {
-    class Node;
+    struct Node;
 
     /// Constraint - Objects of this structure are used to represent the various
     /// constraints identified by the algorithm.  The constraints are 'copy',