Null initialize a few variables flagged by
clang's -Wuninitialized-experimental warning.
While these don't look like real bugs, clang's
-Wuninitialized-experimental analysis is stricter
than GCC's, and these fixes have the benefit
of being general nice cleanups.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124073 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 89b1e9b..f6aea1f 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -4931,7 +4931,7 @@
                              const SDValue *Ops, unsigned NumOps) {
   bool DoCSE = VTs.VTs[VTs.NumVTs-1] != MVT::Glue;
   MachineSDNode *N;
-  void *IP;
+  void *IP = 0;
 
   if (DoCSE) {
     FoldingSetNodeID ID;