diff --git a/include/llvm/Analysis/DataStructure/DataStructure.h b/include/llvm/Analysis/DataStructure/DataStructure.h
index b576dd6b3e9..dccb62e0201 100644
--- a/include/llvm/Analysis/DataStructure/DataStructure.h
+++ b/include/llvm/Analysis/DataStructure/DataStructure.h
@@ -185,7 +185,7 @@ public:
   }
 
 private:
-  bool calculateGraph(DSGraph &G);
+  void calculateGraph(DSGraph &G);
 
   DSGraph &getOrCreateGraph(Function *F);