diff --git a/include/llvm/Support/YAMLParser.h b/include/llvm/Support/YAMLParser.h
index 87117fd..1023995 100644
--- a/include/llvm/Support/YAMLParser.h
+++ b/include/llvm/Support/YAMLParser.h
@@ -513,37 +513,44 @@
 /// @brief Iterator abstraction for Documents over a Stream.
 class document_iterator {
 public:
-  document_iterator() : Doc(NullDoc) {}
-  document_iterator(OwningPtr<Document> &D) : Doc(D) {}
+  document_iterator() : Doc(0) {}
+  document_iterator(OwningPtr<Document> &D) : Doc(&D) {}
 
   bool operator ==(const document_iterator &Other) {
-    return Doc == Other.Doc;
+    if (isAtEnd() || Other.isAtEnd())
+      return isAtEnd() && Other.isAtEnd();
+
+    return *Doc == *Other.Doc;
   }
   bool operator !=(const document_iterator &Other) {
     return !(*this == Other);
   }
 
   document_iterator operator ++() {
-    if (!Doc->skip()) {
-      Doc.reset(0);
+    assert(Doc != 0 && "incrementing iterator past the end.");
+    if (!(*Doc)->skip()) {
+      Doc->reset(0);
     } else {
-      Stream &S = Doc->stream;
-      Doc.reset(new Document(S));
+      Stream &S = (*Doc)->stream;
+      Doc->reset(new Document(S));
     }
     return *this;
   }
 
   Document &operator *() {
-    return *Doc;
+    return *Doc->get();
   }
 
   OwningPtr<Document> &operator ->() {
-    return Doc;
+    return *Doc;
   }
 
 private:
-  static OwningPtr<Document> NullDoc;
-  OwningPtr<Document> &Doc;
+  bool isAtEnd() const {
+    return Doc == 0 || *Doc == 0;
+  }
+
+  OwningPtr<Document> *Doc;
 };
 
 }
diff --git a/lib/Support/YAMLParser.cpp b/lib/Support/YAMLParser.cpp
index fbb6ce9..211ed2c 100644
--- a/lib/Support/YAMLParser.cpp
+++ b/lib/Support/YAMLParser.cpp
@@ -2125,5 +2125,3 @@
   }
   return true;
 }
-
-OwningPtr<Document> document_iterator::NullDoc;