Re: [PATCH] rust: num: bounded: add safety comment for Bounded::__new

[Hsiu Che Yu]

On Mon, Dec 01, 2025 at 01:44:24PM +0100, Miguel Ojeda wrote:
> So typically we have "fixes" or "improvements". The former ones
> typically have Reported-by and Closes (and others like Fixes), while
> improvements don't (and instead Suggested-by would be used in this
> case).
>
> I created the issue in this way to have you think about whether it
> should be `unsafe fn` or not, and depending on the solution, the
> eventual patch would be considered a fix (i.e. making it `unsafe fn`,
> since it would not be intentional) or an improvement (i.e. documenting
> why it is not unsafe, since it would have been intentionally safe).
>
> Here you considered the solution to be that it should not be unsafe,
> in which case it wouldn't be a fix and thus those tags wouldn't be
> used.
>
> The solution to the puzzle is now revealed, and indeed it should be
> `unsafe fn` (even if it is private), so it is indeed a fix (but not
> this fix, of course :).
>
> [ In particular, functions having unsafe code inside of them is
> orthogonal to them being unsafe functions or not, e.g. you may have
> also safe functions with `unsafe` blocks inside. ]
>
> For v2, you should consider what documentation you should add to make
> it `unsafe fn` (please build with `CLIPPY=1` to check) and what others
> changes would be needed.
>
> Thanks for the patch!
>
> Cheers,
> Miguel

I previously believed that a function should only be marked unsafe when 
it directly operates on unsafe code. I now understand that the decision 
should be based on the actual safety implications rather than just 
semantic considerations.

Thank you also for the clarification on the tags. I spent some time 
trying to understand them, and your explanation is very helpful.

I will address this in v2 by making it an `unsafe fn` and documenting
the safety requirements in the `# Safety` section.

Best regards,
Hsiu Che Yu