diff --git a/src/switch_stfu.c b/src/switch_stfu.c
index 8dfd5e1e30..a04889bd51 100644
--- a/src/switch_stfu.c
+++ b/src/switch_stfu.c
@@ -268,7 +268,7 @@ void stfu_n_report(stfu_instance_t *i, stfu_report_t *r)
 stfu_status_t _stfu_n_resize(stfu_instance_t *i, int32_t qlen, int line) 
 {
     stfu_status_t s;
-    uint32_t incr = qlen;
+    int32_t incr = qlen;
 
     if (i->qlen == i->max_qlen) {
         return STFU_IT_FAILED;