Add explicit keywords.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53179 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/IA64/IA64ISelDAGToDAG.cpp b/lib/Target/IA64/IA64ISelDAGToDAG.cpp
index dcd1fe2..85c10fe 100644
--- a/lib/Target/IA64/IA64ISelDAGToDAG.cpp
+++ b/lib/Target/IA64/IA64ISelDAGToDAG.cpp
@@ -40,7 +40,7 @@
     IA64TargetLowering IA64Lowering;
     unsigned GlobalBaseReg;
   public:
-    IA64DAGToDAGISel(IA64TargetMachine &TM)
+    explicit IA64DAGToDAGISel(IA64TargetMachine &TM)
       : SelectionDAGISel(IA64Lowering), IA64Lowering(*TM.getTargetLowering()) {}
     
     virtual bool runOnFunction(Function &Fn) {