[gxml: 17/18] Element.vala: fix issue with freeing xmlAttr memory; don't be overzealous, only free when we'd lose

[Richard Hans Schwarting <rschwart src gnome org>]

commit 15bf4f1f8deffb4756db251905905a9b776cdfbe
Author: Richard Schwarting <aquarichy gmail com>
Date:   Mon Jun 10 00:16:21 2013 -0400

    Element.vala: fix issue with freeing xmlAttr memory; don't be overzealous, only free when we'd lose 
out-of-tree references; in-tree will be handled by xmlFreeDoc

 gxml/Element.vala |   12 +++++++++---
 1 files changed, 9 insertions(+), 3 deletions(-)
---
diff --git a/gxml/Element.vala b/gxml/Element.vala
index 0ee8b89..755365d 100644
--- a/gxml/Element.vala
+++ b/gxml/Element.vala
@@ -156,9 +156,15 @@ namespace GXml {
                                                saved_attr = this.node->set_prop (propname, attr.node_value);
                                        }
 
-                                       // Replace the old out-of-tree attr with the newly allocated one in 
the tree, that way xmlFreeDoc can clean up correctly
-                                       attr.node->free ();
-                                       attr.node = saved_attr;
+                                       /* Replace an old out-of-tree attr with the newly
+                                        * allocated one in the tree, that way xmlFreeDoc can
+                                        * clean up correctly */
+                                       if (attr.node->parent == null) {
+                                               /* If it was in-tree, xmlSetProp should correctly handle the
+                                                  memory when updating the value within its xmlAttr */
+                                               attr.node->free ();
+                                               attr.node = saved_attr;
+                                       }
                                }
                        }
                }