* lib/mi-support.exp (varobj_tree::walk_tree): Set _root_idx

to 0.

gdb/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2013-10-07  Tom Tromey  <tromey@redhat.com>
+
+	* lib/mi-support.exp (varobj_tree::walk_tree): Set _root_idx
+	to 0.
+
 2013-10-06  Sergio Durigan Junior  <sergiodj@redhat.com>
 
 	* gdb.base/corefile.exp: Test whether $_exitsignal is set and

gdb/testsuite/lib/mi-support.exp

@@ -2259,11 +2259,14 @@ namespace eval ::varobj_tree {
   # given varobj TREE.  See detailed explanation above.
   proc walk_tree {language tree callback} {
     global root
+    variable _root_idx
 
     if {[llength $tree] < 3} {
       error "tree does not contain enough elements"
     }
 
+    set _root_idx 0
+
     # Create root node and process the tree.
     array set root [list language $language]
     array set root [list obj_name "root"]