From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH] update-index: Don't copy memory around
Date: Mon, 23 Mar 2015 10:11:08 -0700
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Cc: git@vger.kernel.org, karsten.blees@gmail.com
To: Stefan Beller <sbeller@google.com>
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In-Reply-To: <1427129620-13380-1-git-send-email-sbeller@google.com> (Stefan
	Beller's message of "Mon, 23 Mar 2015 09:53:40 -0700")
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Stefan Beller <sbeller@google.com> writes:

> ... though I do not understand
> why. This passes the test suite, so I wonder if this patch would be a subtle bug
> now.

I recall the last time I traced the code I noticed that the ce can
get passed to a codepath that causes its removal from update_one(),
and then the pathname itself (which used to be ce->name but remember
that ce is invalid already at that point!) is still used after ce is
removed, which was the reason why you would introduce a bug if you
stop copying the path. You may have to follow the code again a bit
closer to make sure but I am reasonably sure that was the reason.