From: Daniel Shumow <shumow@gmail.com>
To: Junio C Hamano <gitster@pobox.com>
Cc: "Ævar Arnfjörð Bjarmason" <avarab@gmail.com>,
Michael <aixtools@felt.demon.nl>,
"brian m. carlson" <sandals@crustytoothpaste.net>,
git@vger.kernel.org, "Jeff King" <peff@peff.net>
Subject: Re: Is detecting endianness at compile-time unworkable?
Date: Mon, 30 Jul 2018 11:39:52 -0700 [thread overview]
Message-ID: <CADMpRy7f_Zr7Ay7bU_5eBS+7yO-58EVsEGE0k9qxefS-TO+z8w@mail.gmail.com> (raw)
In-Reply-To: <xmqqh8kgfuba.fsf@gitster-ct.c.googlers.com>
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The change was definitely made for performance. Removing the if
statements, conditioned upon endianess was an approx 10% improvement, which
was very important to getting this library accepted into git.
Thanks,
Dan
On Mon, Jul 30, 2018 at 11:32 AM, Junio C Hamano <gitster@pobox.com> wrote:
> Junio C Hamano <gitster@pobox.com> writes:
>
> > Ævar Arnfjörð Bjarmason <avarab@gmail.com> writes:
> >
> >> And, as an aside, the reason we can't easily make it better ourselves is
> >> because the build process for git.git doesn't have a facility to run
> >> code to detect this type of stuff (the configure script is always
> >> optional). So we can't just run this test ourselves.
> >
> > It won't help those who cross-compile anyway. I thought we declared
> > "we make a reasonable effort to guess the target endianness from the
> > system header by inspecting usual macros, but will not aim to cover
> > every system on the planet---instead there is a knob to tweak it for
> > those on exotic platforms" last time we discussed this?
>
> Well, having said all that, I do not think I personally mind if
> ./configure learned to include a "compile small program and run it
> to determine byte order on the build machine" as part of "we make a
> reasonable effort" as long as it cleanly excludes cross building
> case (and the result is made overridable just in case we misdetect
> the "cross-ness" of the build).
>
>
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next prev parent reply other threads:[~2018-07-30 18:39 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-07-29 16:44 git broken for AIX somewhere between 2.13.2 and 2.13.3 Michael
2018-07-29 18:10 ` brian m. carlson
2018-07-29 19:46 ` Michael
2018-07-29 20:05 ` Ævar Arnfjörð Bjarmason
2018-07-29 21:40 ` Andreas Schwab
2018-07-30 6:22 ` Michael
[not found] ` <2309fa7f-c2d8-ee57-aff5-b9e32d2da609@felt.demon.nl>
[not found] ` <20180729192753.GD945730@genre.crustytoothpaste.net>
2018-07-29 19:48 ` Michael
2018-07-29 20:06 ` brian m. carlson
2018-07-29 20:50 ` Michael
2018-07-30 9:39 ` Is detecting endianness at compile-time unworkable? Ævar Arnfjörð Bjarmason
2018-07-30 14:54 ` Junio C Hamano
2018-07-30 18:32 ` Junio C Hamano
2018-07-30 18:39 ` Daniel Shumow [this message]
2018-07-31 10:06 ` Michael Felt
2018-08-01 1:35 ` Eric Wong
2018-08-01 7:16 ` Ævar Arnfjörð Bjarmason
2018-07-31 10:39 ` Michael Felt
2018-08-01 7:31 ` Ævar Arnfjörð Bjarmason
2018-08-02 20:50 ` [PATCH] sha1dc: update from upstream Ævar Arnfjörð Bjarmason
2018-08-02 21:29 ` Michael Felt (aixtools)
2018-08-02 21:32 ` Stefan Beller
2018-07-31 12:32 ` Is detecting endianness at compile-time unworkable? Michael Felt
2018-07-31 14:01 ` Michael Felt
2018-07-31 14:25 ` Ævar Arnfjörð Bjarmason
2018-07-31 20:06 ` Michael
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