Silence a warning.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42619 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index 7f2b6e7..63a2579 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -5395,7 +5395,7 @@
       }
     }
 
-    RTLIB::Libcall LC;
+    RTLIB::Libcall LC = RTLIB::UNKNOWN_LIBCALL;
     if (Node->getOperand(0).getValueType() == MVT::f32)
       LC = RTLIB::FPTOUINT_F32_I64;
     else if (Node->getOperand(0).getValueType() == MVT::f64)