diff --git a/lib/CodeGen/MachineFunction.cpp b/lib/CodeGen/MachineFunction.cpp
index 38dd403..cf7f391 100644
--- a/lib/CodeGen/MachineFunction.cpp
+++ b/lib/CodeGen/MachineFunction.cpp
@@ -397,7 +397,7 @@
 }
 
 /// getDebugLocTuple - Get the DebugLocTuple for a given DebugLoc object.
-const DebugLocTuple &MachineFunction::getDebugLocTuple(DebugLoc DL) {
+DebugLocTuple MachineFunction::getDebugLocTuple(DebugLoc DL) const {
   unsigned Idx = DL.getIndex();
   assert(Idx < DebugLocInfo.DebugLocations.size() &&
          "Invalid index into debug locations!");