https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100941
--- Comment #2 from Zdenek Sojka <zsojka at seznam dot cz> --- (In reply to Hongtao.liu from comment #1) > The issue seems to be related to generic part, not target specific > > 006t.gimple > > U foo (V v, W w) > { > U D.2852; > > _1 = {v, { 0, 0, 0, 0 }}; > _2 = BIT_INSERT_EXPR <_1, { 0, 0, 0, 0 }, 0>; <--- why bit position is 0 > but not 256? > D.2852 = BIT_FIELD_REF <_2, 64, 0>; > return D.2852; > } Thank you for having a look. I will re-check with the PR100887 fix applied.