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From:   Junio C Hamano <gitster@pobox.com>
To:     =?utf-8?Q?Ren=C3=A9?= Scharfe <l.s.r@web.de>
Cc:     Johannes Schindelin via GitGitGadget <gitgitgadget@gmail.com>,
        git@vger.kernel.org,
        Johannes Schindelin <johannes.schindelin@gmx.de>
Subject: Re: [PATCH 01/11] mingw: avoid accessing uninitialized memory in
 `is_executable()`
References: <pull.1264.git.1655336146.gitgitgadget@gmail.com>
        <679ea7421f73ce41515aca549982233f88bcefef.1655336146.git.gitgitgadget@gmail.com>
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        <xmqqmtecs6ws.fsf@gitster.g>
Date:   Thu, 16 Jun 2022 13:20:39 -0700
In-Reply-To: <xmqqmtecs6ws.fsf@gitster.g> (Junio C. Hamano's message of "Thu,
        16 Jun 2022 13:13:55 -0700")
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Junio C Hamano <gitster@pobox.com> writes:

>> Hmm, but buf _is_ initialized fully?  Line 149:
>>
>>         char buf[3] = { 0 };
>
> Ahh, yeah, that changes the landscape quite a bit.

Just for reference, this piece of code has been correct ever since
it was introduced to help.c by cc3b7a97 (Windows: Make 'git help -a'
work., 2008-01-14).  With a larger context, we can see buf[3] that
is NUL filled, which receives 2 bytes by read(), and strcmp() does
look semantically more correct than memcmp(), even though there
probably shouldn't be any correctness or performance difference.

So, strcmp -> memcmp in this case is a strict dis-improvement.  I
merged it already to 'next', but I haven't pushed the result out, so
I'll redo 'next' before I push the result out.

Thanks.