diff --git a/contrib/top/utils.c b/contrib/top/utils.c
index a38b2178fcc2..43072b1eccb0 100644
--- a/contrib/top/utils.c
+++ b/contrib/top/utils.c
@@ -499,7 +499,7 @@ unsigned long long amt;
 	}
     }
 
-    p = strecpy(p, itoa(amt));
+    p = strecpy(p, itoa((int)amt));
     *p++ = tag;
     *p = '\0';