https://gcc.gnu.org/bugzilla/show_bug.cgi?id=127952
--- Comment #3 from Gero <gero.peterhoff at gmx dot net> --- That's exactly the problem. https://www.intel.com/content/www/us/en/docs/intrinsics-guide/index.html#text=_addcarry_u64&ig_expand=175 defines “unsigned __int64 *” as an out parameter. Of course, you'd also want to be able to pass “&uint64_t”. No one feels like messing around with compiler internals to figure out exactly how “unsigned __int64 *” is defined.
