https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123799
--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Of course you can convert _BitInt(64) to float or double, and you can bitcast (VCE) double to _BitInt(64) and back. What you can't create is VECTOR_TYPE with BITINT_TYPE elements, similarly how VECTOR_TYPE with POINTER_TYPE elements is not supported.
