diff --git a/pimd/pim_upstream.c b/pimd/pim_upstream.c
index b9cf1e5..6702ca1 100644
--- a/pimd/pim_upstream.c
+++ b/pimd/pim_upstream.c
@@ -355,7 +355,7 @@
 
   up = XMALLOC(MTYPE_PIM_UPSTREAM, sizeof(*up));
   if (!up) {
-    zlog_err("%s: PIM XMALLOC(%d) failure",
+    zlog_err("%s: PIM XMALLOC(%zu) failure",
 	     __PRETTY_FUNCTION__, sizeof(*up));
     return 0;
   }