diff --git a/lib/xfuncs.c b/lib/xfuncs.c
index 1bcaa5e..1942c1e 100644
--- a/lib/xfuncs.c
+++ b/lib/xfuncs.c
@@ -29,7 +29,7 @@
 {
 	pr_emerg("out of memory\n");
 	if (size)
-		pr_emerg("Unable to allocate %d bytes\n", size);
+		pr_emerg("Unable to allocate %zu bytes\n", size);
 
 	malloc_stats();