From: David Edelsohn <dje@watson.ibm.com>
To: Yaro Pollak <yarop@altair-semi.com>
Cc: gcc-help@gcc.gnu.org
Subject: Re: Unaligned access to packed structs on ppc405
Date: Sun, 29 Jan 2006 17:16:00 -0000 [thread overview]
Message-ID: <200601291716.k0THGPD31684@makai.watson.ibm.com> (raw)
>>>>> Yaro Pollak writes:
> I am cross-compiling on GCC 3.4.1 for the PowerPC 405, which can handle
> unaligned accesses in hardware.
> Whenever I am accessing members of a packed bit-struct by pointer, the
> compiler produces byte accesses, instead of 4-byte acceses.
> I've tried to use |-mstrict-align but to no avail.
What does "|-mstrict-align" mean? -mstrict-align means "do not
assume that unaligned accesses are handled by the system." You are
requesting that the compiler assume the target requires strict alignment
and then questioning why it is accessing a packed bit-struct assuming the
least alignment.
David
next reply other threads:[~2006-01-29 17:16 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-01-29 17:16 David Edelsohn [this message]
2006-01-30 12:03 ` Yaro Pollak
2006-02-02 16:13 ` David Edelsohn
-- strict thread matches above, loose matches on Subject: below --
2006-02-05 18:35 John Yates
2006-02-05 21:02 ` David Edelsohn
2006-02-06 10:18 ` Yaro Pollak
2006-02-01 12:03 [Re: Unaligned access to packed structs on ppc405] Yaro Pollak
2006-02-04 4:25 ` Unaligned access to packed structs on ppc405 David Edelsohn
2006-01-30 16:18 Matthew Jones
2006-01-30 16:26 ` Yaro Pollak
2006-01-29 10:00 Yaro Pollak
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
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=200601291716.k0THGPD31684@makai.watson.ibm.com \
--to=dje@watson.ibm.com \
--cc=gcc-help@gcc.gnu.org \
--cc=yarop@altair-semi.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.
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).