1 files changed, 1 insertions, 1 deletions
diff --git a/marshal.c b/marshal.c
index e6672d229c..e52508db25 100644
--- a/marshal.c
+++ b/marshal.c
@@ -114,7 +114,7 @@ w_bytes(s, n, arg)
 	fwrite(s, 1, n, arg->fp);
     }
     else {
-	rb_str_cat(arg->str, s, n);
+	rb_str_buf_cat(arg->str, s, n);
     }
 }