Re: [PATCH v7 02/10] rust: bitmap: restrict bitmap length to at most i32::MAX

[Alexandre Courbot]

On Mon Aug 17, 2026 at 4:04 PM JST, Eliot Courtney wrote:
> It is currently possible to construct a non-`BitmapVec` backed
> `Bitmap` using `Bitmap::from_raw` that is larger than `i32::MAX`, and
> it is not part of the unsafe requirements. Restricting all bitmaps
> (even non-`BitmapVec` backed ones) to a maximum size of `i32::MAX`
> simplifies a few things and matches `BitmapVec::MAX_LEN`.

Can we be more explicit (if possible in the doccomments as well) about
what "a few things" is? IIUC we are doing this because some of the C
APIs take an `int`, so we can just state that much.

Note also (as a point to consider, not a review ask) that we could
enforce this requirement in the type system if we made `nbits` a
`Bounded<usize, 31>`. Currently `from_raw` and `from_raw_mut` are
unsafe, so this becomes one more invariant for the caller to uphold, but
would we have made them unsafe just for this if they weren't already?