https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79118
--- Comment #6 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
So, cxx_eval_bit_field_ref is trying to evaluate
BIT_FIELD_REF <*(struct basic_monad_storage *) this, 8, 8>
here. It first evaluates the struct expression which yields
{._storage={.D.2530={.D.2503={._value_raw=0}}}}
and then looks at the ctor element and tries to find something at bit position
8 and size 8, but is not finding it -> ICE.
