id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	uname	nginx_version
1531	ngx_rbtree.h	lwppwl@…		"in ngx_rbtree.h[[BR]]

in function ngx_rbtree_min()

static ngx_inline ngx_rbtree_node_t *                                            
ngx_rbtree_min(ngx_rbtree_node_t *node, ngx_rbtree_node_t *sentinel)             
{                                                                                
     while (node->left != sentinel)                                               
     {                                                                            
         node = node->left;                                                       
     }                                                                            
                                                                                  
     return node;                                                                 
}

after delete all node, when call ngx_rbtree_min(tree->root, tree->sentinel) casue Segment error.

should be fix like this:

static inline ngx_rbtree_node_t *                                                 
ngx_rbtree_min(ngx_rbtree_node_t *node, ngx_rbtree_node_t *sentinel)                
{                                                                                
    while (node != sentinel && node->left != sentinel)                           
    {                                                                            
        node = node->left;                                                       
    }                                                                            
                                                                                 
    if (node == sentinel)                                                        
    {                                                                            
        return NULL;                                                             
    }                                                                            
                                                                                                  
    return node;                                                                 
}"	defect	closed	minor		other	1.13.x	invalid			 Linux lwp-All-Series 4.10.0-19-generic #21-Ubuntu SMP Thu Apr 6 17:04:57 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux 	nginx-1.12.2