Re: [PATCH v3 0/4] rust: alloc: add Vec shrinking methods

[Shivam Kalra]

On 11/02/26 02:41, Danilo Krummrich wrote:
> On Tue Feb 10, 2026 at 9:58 PM CET, Alice Ryhl wrote:
>> On Tue, Feb 10, 2026 at 9:54 PM Danilo Krummrich <dakr@xxxxxxxxxx> wrote:
>> Yes that's what I meant. Only provide shrink_to() for those. After
>> all, if Kmalloc never actually shrinks when you call realloc, what's
>> the point of having KVec::shrink_to()?
> 
> Nothing, but eventually we want a generic impl of shrink_to() with A::realloc().
> But again, for now that's fine.
Thanks for the discussion. Just want to confirm my understanding
of the agreed approach:

Since VVec and KVVec are type aliases for Vec<T, Vmalloc> and
Vec<T, KVmalloc>, implementing shrink_to() on "only VVec and KVVec"
means writing separate impl blocks:

  impl<T> Vec<T, Vmalloc> { fn shrink_to() { ... } }
  impl<T> Vec<T, KVmalloc> { fn shrink_to() { ... } }

Is that what you had in mind, with the shrink logic duplicated
in both? Or would you prefer a shared impl with a trait bound to
avoid duplication?