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

From: Karthik Nayak <karthik.188@gmail.com>
Date: Jul 22, 2025, 08:44 UTC
Message-ID: <CAOLa=ZTE_Hmnz5EMxAk94rSsvvT7+O9PrroLTbjPW_oe6AzCVw@mail.gmail.com>
In-Reply-To: <20250721212221.GA818305@coredump.intra.peff.net>

Jeff King <peff@peff.net> writes:

Show 22 quoted lines

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

That makes sense, thanks for explaining.

> -Peff