diff --git a/c/msgpack/zbuffer.h b/c/msgpack/zbuffer.h
index cfcba29e..26eb29f4 100644
--- a/c/msgpack/zbuffer.h
+++ b/c/msgpack/zbuffer.h
@@ -125,7 +125,9 @@ char* msgpack_zbuffer_flush(msgpack_zbuffer* zbuf)
 		case Z_STREAM_END:
 			return zbuf->data;
 		case Z_OK:
-			msgpack_zbuffer_expand(zbuf);
+			if(!msgpack_zbuffer_expand(zbuf)) {
+				return NULL;
+			}
 			break;
 		default:
 			return NULL;