Ticket #26634: 26634.patch

wp-includes/query.php

@@ -3273 +3273 @@
 
                                 if ( 'term_id' == $query['field'] )
                                         $term = get_term( reset( $query['terms'] ), $query['taxonomy'] );
-                                else
+                                elseif ( $query['terms'] )
                                         $term = get_term_by( $query['field'], reset( $query['terms'] ), $query['taxonomy'] );
                         }