Re: [PATCH v5 0/5] for-each-ref: introduce seeking functionality via '--start-after'

From: Jeff King <peff@peff.net>
Date: Jul 21, 2025, 21:22 UTC
Message-ID: <20250721212221.GA818305@coredump.intra.peff.net>
In-Reply-To: <CAOLa=ZR==xihNsZcNkFPtqb1JbC+EbMHtgF-RUzdwOQp55+MOw@mail.gmail.com>

On Mon, Jul 21, 2025 at 02:27:45PM +0000, Karthik Nayak wrote:

Show 12 quoted lines

> > Applying this ancient patch:
> >
> >   https://lore.kernel.org/git/20171004101932.pai6wzcv2eohsicr@sigill.intra.peff.net/
> >
> > and building with "make SANITIZE=memory CC=clang" let me run t6302 to
> > completion, modulo the bug that started this thread (and which I
> > confirmed goes away both with MSan and valgrind with the fix Karthik
> > posted).
> [...]
> 
> I wonder if an alternate is to use '-fsanitize-ignorelist', since the
> MemorySanitizer is supposed to work with that too [1].

I think you could do that, but it isn't quite what we want: it is annotating the access of those (false-positive) "uninitialized" bytes. So you have to mark every spot that touches bytes that come from zlib, which in Git is a lot of places. And so the patch linked above was an attempt to silence all of those with a single line: marking the bytes coming out of zlib as OK.

-Peff