diff --git a/orte/mca/ess/hnp/ess_hnp_module.c b/orte/mca/ess/hnp/ess_hnp_module.c
index ef49542eb4..73843d8782 100644
--- a/orte/mca/ess/hnp/ess_hnp_module.c
+++ b/orte/mca/ess/hnp/ess_hnp_module.c
@@ -186,7 +186,7 @@ static int rte_init(void)
 #if OPAL_HAVE_HWLOC
     {
         hwloc_obj_t obj;
-        int i, j;
+        unsigned i, j;
 
         /* get the local topology */
         if (NULL == opal_hwloc_topology) {