Re: [PATCH 0/2] Rust hash cleanups

[Jeff King <peff@peff.net>]

On Sun, Jul 19, 2026 at 01:08:40AM +0000, brian m. carlson wrote:

> Peff recently sent out a series to fix several memory leaks with our
> hashing code when not using the default block algorithm.  This series
> follows up with a few fixes to our Rust hash code, which calls the C
> code, to fix various memory problems.

Both of these look good to me (modulo my almost-zero knowledge of the
Rust bits).

I was worried at first that I had introduced new problems with my fixes,
but I think these are both pre-existing issues (really just variants of
the cleanups I did in the C code).

For patch 1, an alternative is to switch git_hash_clone() to _not_
require initialization. But it introduces the leak problem in the
opposite direction. E.g., hashfile_truncate() wants to overwrite
existing state, so it would now need to discard() before cloning. I
doubt it's worth the effort or risk of regression to save the tiny bit
of effort spent on a few init-then-overwrite cases.

So the approach taken here makes sense (and obviously this is just
following the C code's lead anyway).

-Peff