Fix the config parser so that if there is no current node, and we are

evaluating an EXEC_ON_READ directive, and the directive's sub_tree is empty,
we don't try to set the node's parent pointer.  This stops a seg fault.
Submitted by:	Jeff Trawick


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@85269 13f79535-47bb-0310-9956-ffa450edef68

server/config.c

@@ -876,6 +876,8 @@ static const char * ap_build_config_sub(ap_pool_t *p, ap_pool_t *temp_pool,
                 (*current) = sub_tree;
                 if (*curr_parent) {
                     (*curr_parent)->first_child = (*current);
+                }
+                if (*current) {
                     (*current)->parent = (*curr_parent);
                 }
             }