git@vger.kernel.org mailing list mirror (one of many)
 help / color / mirror / code / Atom feed
From: "Liam R. Howlett" <Liam.Howlett@Oracle.com>
To: Junio C Hamano <gitster@pobox.com>
Cc: Michael Kebe <michael.kebe@gmail.com>,
	?var Arnfj?r? Bjarmason <avarab@gmail.com>,
	Git Mailing List <git@vger.kernel.org>,
	Marc Stevens <marc@marc-stevens.nl>
Subject: Re: Compile Error v2.13.2 on Solaris SPARC
Date: Tue, 27 Jun 2017 14:29:42 -0400	[thread overview]
Message-ID: <20170627182942.gpug4xaek2vba7uh@oracle.com> (raw)
In-Reply-To: <xmqq1sq52uwj.fsf@gitster.mtv.corp.google.com>

* Junio C Hamano <gitster@pobox.com> [170627 13:38]:
> "Liam R. Howlett" <Liam.Howlett@Oracle.com> writes:
> 
> > How about:
> >
> > ---- 8< ----
> > diff --git a/sha1dc/sha1.c b/sha1dc/sha1.c
> > index facea1bb5..ed8c63f2d 100644
> > --- a/sha1dc/sha1.c
> > +++ b/sha1dc/sha1.c
> > @@ -38,9 +38,18 @@
> >  
> >  #if (defined(_BYTE_ORDER) || defined(__BYTE_ORDER) || defined(__BYTE_ORDER__))
> >  
> > +#define EMPTY_VAL(x) x ## 1
> > +#define EMPTY(x) EMPTY_VAL(x)
> > +
> > +#if (defined(_BIG_ENDIAN) && (EMPTY(_BIG_ENDIAN) == 1))
> > +#undef _BIG_ENDIAN
> > +#define _BIG_ENDIAN 4321
> > +#endif
> 
> I'd say it is a bad idea to define a symbol that you _know_ a
> platform header file defines.  Any header you may include from the
> platform after these lines still expects the symbol to be defined in
> a way it defines without getting molested and will misbehave.

Okay.  Thanks.  I thought a c file would be safe, especially after the
includes but there is indeed a possible include (ifdef'ed) later.

This compressed logic is causing a lot of issues.  Could we just rewrite
it as a whole lot of #if/#else, statements to avoid running across the
issue where the precompiler does not short-circuit the checks?  Would
this cause any other issues?

Alternatively, we can replace the undef/define with the define of
SHA1DC_BIGENDIAN and make this an #if/#else..

A third option is to compile a small test and just -DSHA1DC_BIGENDIAN in
the Makefile.

Cheers,
Liam


  reply	other threads:[~2017-06-27 18:29 UTC|newest]

Thread overview: 59+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-06-26  7:32 Compile Error v2.13.2 on Solaris SPARC Michael Kebe
     [not found] ` <87lgofcf7r.fsf@gmail.com>
2017-06-26 12:36   ` Michael Kebe
2017-06-26 12:47     ` Ævar Arnfjörð Bjarmason
2017-06-26 14:00       ` Michael Kebe
2017-06-26 18:31         ` Ævar Arnfjörð Bjarmason
2017-06-26 18:29       ` Liam R. Howlett
     [not found] ` <87fuem7aw2.fsf@gmail.com>
2017-06-27  5:41   ` Michael Kebe
2017-06-27  6:28     ` Michael Kebe
2017-06-27 16:28       ` Liam R. Howlett
2017-06-27 17:38         ` Junio C Hamano
2017-06-27 18:29           ` Liam R. Howlett [this message]
2017-06-27 18:55             ` Ævar Arnfjörð Bjarmason
2017-06-27 17:59         ` Ævar Arnfjörð Bjarmason
2017-06-27 12:17 ` [PATCH 0/3] update sha1dc from PR #36 Ævar Arnfjörð Bjarmason
2017-06-27 18:37   ` Stefan Beller
2017-06-27 20:33   ` [PATCH v2 " Ævar Arnfjörð Bjarmason
2017-06-27 21:37     ` Junio C Hamano
2017-06-27 21:38     ` Junio C Hamano
2017-06-27 22:24       ` Ævar Arnfjörð Bjarmason
2017-06-28 21:42       ` Ævar Arnfjörð Bjarmason
2017-06-28 22:02         ` Junio C Hamano
2017-06-27 20:33   ` [PATCH v2 1/3] sha1dc: correct endian detection for Solaris (and others?) Ævar Arnfjörð Bjarmason
2017-06-27 20:33   ` [PATCH v2 2/3] sha1dc: optionally use sha1collisiondetection as a submodule Ævar Arnfjörð Bjarmason
2017-06-27 20:33   ` [PATCH v2 3/3] sha1collisiondetection: automatically enable when submodule is populated Ævar Arnfjörð Bjarmason
2017-07-01 22:05   ` [PATCH v3 0/3] Update sha1dc from upstream Ævar Arnfjörð Bjarmason
2017-07-01 22:05   ` [PATCH v3 1/3] sha1dc: update " Ævar Arnfjörð Bjarmason
2017-07-01 22:05   ` [PATCH v3 2/3] sha1dc: optionally use sha1collisiondetection as a submodule Ævar Arnfjörð Bjarmason
2017-07-03 17:11     ` Junio C Hamano
2017-07-03 20:29       ` Ævar Arnfjörð Bjarmason
2017-07-04 17:26         ` Junio C Hamano
2017-07-04 22:50           ` Ævar Arnfjörð Bjarmason
2017-07-05  0:36             ` Stefan Beller
2017-07-05  1:56               ` Junio C Hamano
2017-07-05 17:46                 ` Stefan Beller
2017-07-05 18:03                   ` Ævar Arnfjörð Bjarmason
2017-07-01 22:05   ` [PATCH v3 3/3] sha1collisiondetection: automatically enable when submodule is populated Ævar Arnfjörð Bjarmason
2017-06-27 12:17 ` [PATCH 1/3] sha1dc: update from my PR #36 Ævar Arnfjörð Bjarmason
2017-06-27 15:22   ` Junio C Hamano
2017-06-27 15:53     ` Junio C Hamano
2017-06-27 18:07       ` Ævar Arnfjörð Bjarmason
2017-06-27 15:55     ` Junio C Hamano
2017-06-27 16:31       ` Liam R. Howlett
2017-06-27 18:11       ` Ævar Arnfjörð Bjarmason
2017-06-27 19:10         ` Junio C Hamano
2017-06-27 19:33           ` Junio C Hamano
2017-06-27 19:35           ` Ævar Arnfjörð Bjarmason
2017-06-27 19:38             ` Junio C Hamano
2017-06-27 19:38           ` Liam R. Howlett
2017-06-27 19:48             ` Junio C Hamano
2017-06-27 18:06     ` Ævar Arnfjörð Bjarmason
2017-06-27 18:12       ` Junio C Hamano
2017-06-27 18:19         ` Ævar Arnfjörð Bjarmason
2017-06-27 20:17           ` Junio C Hamano
2017-06-27 18:23       ` Junio C Hamano
2017-06-27 18:52         ` Ævar Arnfjörð Bjarmason
2017-06-27 12:17 ` [PATCH 2/3] sha1dc: optionally use sha1collisiondetection as a submodule Ævar Arnfjörð Bjarmason
2017-06-27 18:46   ` Stefan Beller
2017-06-27 18:56     ` Ævar Arnfjörð Bjarmason
2017-06-27 12:17 ` [PATCH 3/3] sha1collisiondetection: automatically enable when submodule is populated Ævar Arnfjörð Bjarmason

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

  List information: http://vger.kernel.org/majordomo-info.html

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20170627182942.gpug4xaek2vba7uh@oracle.com \
    --to=liam.howlett@oracle.com \
    --cc=avarab@gmail.com \
    --cc=git@vger.kernel.org \
    --cc=gitster@pobox.com \
    --cc=marc@marc-stevens.nl \
    --cc=michael.kebe@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
Code repositories for project(s) associated with this public inbox

	https://80x24.org/mirrors/git.git

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).