diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index 1431ba4cd2a..186def79e26 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -736,6 +736,7 @@ void LiveIntervals::computeLiveInRegUnits() {
           NewIntvs.push_back(Intv);
         }
         VNInfo *VNI = Intv->createDeadDef(Begin, getVNInfoAllocator());
+        (void)VNI;
         DEBUG(dbgs() << ' ' << PrintRegUnit(Unit, TRI) << '#' << VNI->id);
       }
     }