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From:   Junio C Hamano <gitster@pobox.com>
To:     Jeff King <peff@peff.net>
Cc:     =?utf-8?B?w4Z2YXIgQXJuZmrDtnLDsA==?= Bjarmason <avarab@gmail.com>,
        Johannes Sixt <j6t@kdbg.org>,
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        git@vger.kernel.org
Subject: Re: [PATCH 5/5] cbtree.h: define cb_init() in terms of CBTREE_INIT
References: <cover-0.5-00000000000-20210927T003330Z-avarab@gmail.com>
        <patch-5.5-7e571667674-20210927T003330Z-avarab@gmail.com>
        <694f477d-b387-c8ea-4138-0e9334540c69@kdbg.org>
        <87czou1dmp.fsf@evledraar.gmail.com>
        <YVJZrOYucywgoi+v@coredump.intra.peff.net>
Date:   Tue, 28 Sep 2021 11:32:02 -0700
In-Reply-To: <YVJZrOYucywgoi+v@coredump.intra.peff.net> (Jeff King's message
        of "Mon, 27 Sep 2021 19:54:20 -0400")
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Jeff King <peff@peff.net> writes:

>> >> +	memcpy(t, &blank, sizeof(*t));
>> >
>> > Is
>> > 	*t = blank;
>> >
>> > not a thing in C?
>
> It would be fine to use struct assignment here, and should be equivalent
> in most compilers. They know about memcpy() and will inline it as
> appropriate.

FWIW, I'd be fine with structure assignment, but we already have too
many such memcpy(<ptr>, &<struct>, sizeof(struct)), adding one more
is not giving us too much incremental burden for later clean-up.

> I think some C programmers tend to prefer memcpy() just because that's
> how they think. It also wasn't legal in old K&R compilers, but as far as
> I know was in C89.

I think so, too.