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Date: Thu, 26 Mar 2026 11:55:58 +0100
Message-Id: <DHCNQXCUUEDI.1NVFTYVFBMTE3@kernel.org>
To: "David Rheinsberg" <david@readahead.eu>
From: "Danilo Krummrich" <dakr@kernel.org>
Subject: Re: [PATCH] rust/alloc: add Vec::into_boxed_slice()
Cc: "Alice Ryhl" <aliceryhl@google.com>, <rust-for-linux@vger.kernel.org>,
 "Lorenzo Stoakes" <lorenzo.stoakes@oracle.com>, "Vlastimil Babka"
 <vbabka@kernel.org>, "Liam R. Howlett" <Liam.Howlett@oracle.com>,
 "Uladzislau Rezki" <urezki@gmail.com>, "Boqun Feng" <boqun@kernel.org>,
 "Gary Guo" <gary@garyguo.net>, =?utf-8?q?Bj=C3=B6rn_Roy_Baron?=
 <bjorn3_gh@protonmail.com>, "Benno Lossin" <lossin@kernel.org>, "Andreas
 Hindborg" <a.hindborg@kernel.org>, "Trevor Gross" <tmgross@umich.edu>,
 <linux-kernel@vger.kernel.org>
References: <20260326095621.846840-1-david@readahead.eu>
 <acULYP6ejIQAIdX-@google.com>
 <afe9ff28-573c-4760-a310-87d4561bff8d@app.fastmail.com>
In-Reply-To: <afe9ff28-573c-4760-a310-87d4561bff8d@app.fastmail.com>

On Thu Mar 26, 2026 at 11:45 AM CET, David Rheinsberg wrote:
> On Thu, Mar 26, 2026, at 11:33 AM, Alice Ryhl wrote:
>> We currently say that you should provide the right length when freeing
>> an allocation, but this is going to violate that. You should probably
>> invoke realloc here, like stdlib does.

Ok, Alice was faster. :)

> `std` calls `shrink_to_fit()`. Should I add it as well? How about
> `shrink_to()`? I don't particularly need them, but I can expose them as w=
ell,
> given that I would have to implement those.

Let's stick to A::realloc(), that's the only thing we need to justify the s=
afety
requirement. I don't want to rely on shrink_to() and shrink_to_fit() not do=
ing
additional things we don't need for this conversion.