diff --git a/lib/Analysis/IPA/CallGraph.cpp b/lib/Analysis/IPA/CallGraph.cpp
index 74a28d818d7..70bf2c496b0 100644
--- a/lib/Analysis/IPA/CallGraph.cpp
+++ b/lib/Analysis/IPA/CallGraph.cpp
@@ -126,6 +126,7 @@ void CallGraph::destroy() {
     delete I->second;
   FunctionMap.clear();
   delete CallsExternalNode;
+  CallsExternalNode = 0;
 }
 
 static void WriteToOutput(const CallGraphNode *CGN, std::ostream &o) {