offset += bytes;
 
        /* make sure off_t is sufficiently large not to wrap */
-       if (consumed_bytes > consumed_bytes + bytes)
+       if (signed_add_overflows(consumed_bytes, bytes))
                die("pack too large for current definition of off_t");
        consumed_bytes += bytes;
 }
 
 static void *get_data(unsigned long size)
 {
-       z_stream stream;
+       git_zstream stream;
        void *buf = xmalloc(size);
 
        memset(&stream, 0, sizeof(stream));
                if (stream.total_out == size && ret == Z_STREAM_END)
                        break;
                if (ret != Z_OK) {
-                       error("inflate returned %d\n", ret);
+                       error("inflate returned %d", ret);
                        free(buf);
                        buf = NULL;
                        if (!recover)