diff --git a/skeletons/constraints.c b/skeletons/constraints.c
index 9c34885..9b60545 100644
--- a/skeletons/constraints.c
+++ b/skeletons/constraints.c
@@ -99,7 +99,7 @@
 	}
 
 	if(ret < (ssize_t)sizeof(buf)) {
-		cb(buf, ret, key);
+		(void)cb(buf, ret, key);
 		return;
 	}
 
@@ -120,5 +120,5 @@
 		p = buf;
 	}
 
-	cb(p, ret, key);
+	(void)cb(p, ret, key);
 }