stop using DebugLoc::getUnknownLoc()


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100215 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 59ac24b..879bdb2 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -546,7 +546,7 @@
   PendingExports.clear();
   EdgeMapping.clear();
   DAG.clear();
-  CurDebugLoc = DebugLoc::getUnknownLoc();
+  CurDebugLoc = DebugLoc();
   HasTailCall = false;
 }