consistenttime crate

[burdges]

Just fyi the consistenttime crate looks a bit more developed and saw at least some auditing valarauca/consistenttime#5 (comment)

[cesarb]

Thanks for the tip! That crate also uses the same #[inline(never)] trick I used, plus some other more advanced "confuse the optimizer" tricks, though it doesn't do the only really guaranteed way (inline "no-operation" assembly, or call to C function), which I don't do also here (I only did it so far for the clear_on_drop crate).

I'll see later if I submit the "slice trick" which I use here to that crate, for some extra speed.