Previously GraphWriter assumed operator*() for node_iterator always

returned a reference type.  This patch allows operator*() to return a
non-reference type while still maintaining the old behavior when it
does return a reference type.

This patch was motivated when I tried to use "df_iterator" (see
llvm/ADT/DepthFirstIterator.h) as a "node_iterator", as df_iterator
does not return a reference type and thus we would get a compilation
error when trying to take the address of a temporary.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42151 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/Support/GraphWriter.h b/include/llvm/Support/GraphWriter.h
index 08bc861332796272f309694e079d19ec318540cb..85cf71805fd69fa8e905dff2bc9d7df56e47e046 100644 (file)
--- a/include/llvm/Support/GraphWriter.h
+++ b/include/llvm/Support/GraphWriter.h
@@ -101,7 +101,11 @@ public:
     // Loop over the graph, printing it out...
     for (node_iterator I = GTraits::nodes_begin(G), E = GTraits::nodes_end(G);
          I != E; ++I)
-      writeNode(&*I);
+      writeNode(*I);
+  }
+  
+  void writeNode(NodeType& Node) {
+    writeNode(&Node);
   }
 
   void writeNode(NodeType *const *Node) {