Given that big int libraries have existed for a while, why is there a pressing need now?
That is, the largest possible unsigned integer type that has native arithmetic support.
What keeps this from suffering the same problems as intmax_t; i.e., once baked into ABIs it is effectively impossible to change when the underlying hardware does.
I'm thus interested in standardizing a type alias in <stdint.h> that has the size. In P4444, we call that uint_multiprecision_t, but that's perhaps not universal enough. Names like "uint_maxfast_t" or "uint_word_t" come to mind.
I was never really enamoured with the int_fastN_t types, since they don't guarantee, well, anything other than being at least N bits wide. This doesn't seem any different, because "fast" isn't clearly defined.
That we are re-inventing int, badly. The original intention of int was that it be the "fastest" type on the target, whatever that means.
Also, since I'm not in the C committee myself, is there anyone who is interested in championing a proposal on the WG14 side?
I am not interested, and this seems a bit premature.