silence a bogus warning

llvm-svn: 22245
diff --git a/llvm/lib/Target/X86/X86ISelPattern.cpp b/llvm/lib/Target/X86/X86ISelPattern.cpp
index c3b0e5a..8ffcc82 100644
--- a/llvm/lib/Target/X86/X86ISelPattern.cpp
+++ b/llvm/lib/Target/X86/X86ISelPattern.cpp
@@ -3862,7 +3862,7 @@
   SDOperand Callee = TailCallNode->getOperand(1);
   bool isDirect = isa<GlobalAddressSDNode>(Callee) ||
                   isa<ExternalSymbolSDNode>(Callee);
-  unsigned CalleeReg;
+  unsigned CalleeReg = 0;
   if (!isDirect) CalleeReg = SelectExpr(Callee);
 
   unsigned RegOp1 = 0;