https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114157
--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Ah, we need to handle BIT_FIELD_REF from some SSA_NAME to large/huge _BitInt: void foo (vector(8) long int s) { _BitInt(256) _2; <bb 2> [local count: 1073741824]: _2 = BIT_FIELD_REF <s_1(D), 256, 0>; MEM <_BitInt(256)> [(char * {ref-all})&d] = _2; maybe also BIT_FIELD_REF from large/huge _BitInt to non-bitint and maybe also from/to large/huge _BitInt. Though, I really can't reproduce those cases right now, so it would be purely theoretical.