1 files changed, 1 insertions, 1 deletions
diff --git a/marshal.c b/marshal.c
index f78464d16..fda961fdf 100644
--- a/marshal.c
+++ b/marshal.c
@@ -937,7 +937,7 @@ r_byte(struct load_arg *arg)
 static void
 long_toobig(int size)
 {
-    rb_raise(rb_eTypeError, "long too big for this architecture (size %d, given %d)",
+    rb_raise(rb_eTypeError, "long too big for this architecture (size %zd, given %d)",
 	     sizeof(long), size);
 }