From: Junio C Hamano <gitster@pobox.com>
Date: Thu, 09 Jun 2016 19:19:31 GMT
Subject: Re: [PATCH 1/2] submodule--helper: initial clone learns retry logic
Message-ID: <xmqqy46egofw.fsf@gitster.mtv.corp.google.com>
In-Reply-To: <20160609190637.21177-2-sbeller@google.com>

Stefan Beller <sbeller@google.com> writes:

> +static int compare_ce(const void *one, const void *two, void *cb_data)
> +{
> +	const struct cache_entry *ce_one = one, *ce_two = two;
> +	return ce_two - ce_one;
> +}

This would work in practice, but I suspect that this is not ANSI-C
kosher; as address comparison for ordering (not equality) is
undefined if two pointers are not pointing into the same array or
into the same struct's fields.

I think we have one or two other instances of such fishy pointer
comparison already in the codebase, so it is not a show-stopper, but
it would be better if this can be avoided and be replaced with
something that I do not have to raise eyebrows at ;-)