Pointer asserts in GetStr()
diff --git a/tinyxml2.cpp b/tinyxml2.cpp
index 42659f2..113f884 100755
--- a/tinyxml2.cpp
+++ b/tinyxml2.cpp
@@ -186,6 +186,8 @@
 

 const char* StrPair::GetStr()

 {

+    TIXMLASSERT( _start );

+    TIXMLASSERT( _end );

     if ( _flags & NEEDS_FLUSH ) {

         *_end = 0;

         _flags ^= NEEDS_FLUSH;

@@ -267,6 +269,7 @@
         }

         _flags = (_flags & NEEDS_DELETE);

     }

+    TIXMLASSERT( _start );

     return _start;

 }