https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69508
--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Note that passing the _Bool to varargs function might very well zero extend it (i.e. mask with 1). As kernel is built with -fno-strict-aliasing, I bet trying to print *(char *)&tid_agg_rx->removed instead might give you more accurate answers.