diff --git a/lib/CompilerDriver/CompilationGraph.cpp b/lib/CompilerDriver/CompilationGraph.cpp
index 5781cda..3e6e050 100644
--- a/lib/CompilerDriver/CompilationGraph.cpp
+++ b/lib/CompilerDriver/CompilationGraph.cpp
@@ -471,6 +471,7 @@
   struct DOTGraphTraits<llvmc::CompilationGraph*>
     : public DefaultDOTGraphTraits
   {
+    DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {}
 
     template<typename GraphType>
     static std::string getNodeLabel(const Node* N, const GraphType&)