public inbox for binutils@sourceware.org
 help / color / mirror / Atom feed
From: Daniel Jacobowitz <drow@false.org>
To: binutils@sourceware.org, binutils@sources.redhat.com
Cc: "H. J. Lu" <hjl@lucon.org>, Vivek Goyal <vgoyal@redhat.com>
Subject: Re: Linker Bug or Design Intent (Absolute symbols in zero sized sections)
Date: Wed, 27 Sep 2006 01:51:00 -0000	[thread overview]
Message-ID: <20060926235350.GA4214@nevyn.them.org> (raw)
In-Reply-To: <20060926232714.GA1534@bubble.grove.modra.org>

On Wed, Sep 27, 2006 at 08:57:14AM +0930, Alan Modra wrote:
> On Tue, Sep 26, 2006 at 12:45:20PM -0400, Daniel Jacobowitz wrote:
> > On Tue, Sep 26, 2006 at 09:30:24AM -0700, H. J. Lu wrote:
> > > Convert section relative symbol to absolute shouldn't be a problem
> > > in most cases. If we know it may be a problem at link time, we can
> > > keep it section relative.
> > 
> > You keep saying this, but on various platforms it isn't true.  Section
> > relative symbols move with an object if it is relocated in any way.
> > Absolute symbols don't.
> 
> This isn't true for the common ELF targets.  An absolute symbol in a
> shared library is effectively relative to the base of the shared lib.
> A sad consequence of defining syms like _GLOBAL_OFFSET_TABLE_ and
> _DYNAMIC as absolute.

Which I tried to change, you may recall :-)  For those platforms which
do care, absolute _G_O_T_ is a serious problem, and there's a knob for
it.

-- 
Daniel Jacobowitz
CodeSourcery

WARNING: multiple messages have this Message-ID
From: Daniel Jacobowitz <drow@false.org>
To: binutils@sourceware.org, binutils@sources.redhat.com
Cc: "H. J. Lu" <hjl@lucon.org>, Vivek Goyal <vgoyal@redhat.com>
Subject: Re: Linker Bug or Design Intent (Absolute symbols in zero sized sections)
Date: Wed, 27 Sep 2006 03:09:00 -0000	[thread overview]
Message-ID: <20060926235350.GA4214@nevyn.them.org> (raw)
Message-ID: <20060927030900.x1u1s-UKAEuvmPLx_gpvrI2rj9Q7owhyCWefqNEiHlw@z> (raw)
In-Reply-To: <20060926232714.GA1534@bubble.grove.modra.org>

On Wed, Sep 27, 2006 at 08:57:14AM +0930, Alan Modra wrote:
> On Tue, Sep 26, 2006 at 12:45:20PM -0400, Daniel Jacobowitz wrote:
> > On Tue, Sep 26, 2006 at 09:30:24AM -0700, H. J. Lu wrote:
> > > Convert section relative symbol to absolute shouldn't be a problem
> > > in most cases. If we know it may be a problem at link time, we can
> > > keep it section relative.
> > 
> > You keep saying this, but on various platforms it isn't true.  Section
> > relative symbols move with an object if it is relocated in any way.
> > Absolute symbols don't.
> 
> This isn't true for the common ELF targets.  An absolute symbol in a
> shared library is effectively relative to the base of the shared lib.
> A sad consequence of defining syms like _GLOBAL_OFFSET_TABLE_ and
> _DYNAMIC as absolute.

Which I tried to change, you may recall :-)  For those platforms which
do care, absolute _G_O_T_ is a serious problem, and there's a knob for
it.

-- 
Daniel Jacobowitz
CodeSourcery

  reply	other threads:[~2006-09-26 23:53 UTC|newest]

Thread overview: 43+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-09-26 14:33 Vivek Goyal
2006-09-26 14:49 ` H. J. Lu
2006-09-26 14:52   ` Vivek Goyal
2006-09-26 15:13     ` H. J. Lu
2006-09-26 15:41       ` Daniel Jacobowitz
2006-09-26 15:54         ` Vivek Goyal
2006-09-26 16:21           ` H. J. Lu
2006-09-26 16:30             ` Vivek Goyal
2006-09-26 16:44               ` H. J. Lu
2006-09-26 16:45                 ` Vivek Goyal
2006-09-26 17:01                 ` Daniel Jacobowitz
2006-09-26 23:50                   ` Alan Modra
2006-09-27  1:51                     ` Daniel Jacobowitz [this message]
2006-09-27  3:09                       ` Daniel Jacobowitz
2006-09-26 17:48                 ` Paul Koning
2006-09-26 23:53                   ` Alan Modra
2006-09-28 17:01                     ` Paul Brook
2006-09-28 17:05                       ` Paul Brook
2006-09-28 18:37                       ` H. J. Lu
2006-09-28 18:53                         ` H. J. Lu
2006-10-10 16:41                         ` Jakub Jelinek
2006-10-10 16:51                           ` Jakub Jelinek
2006-10-11  3:52                           ` Jakub Jelinek
2006-10-11  7:12                             ` Jakub Jelinek
2006-10-11  8:04                             ` Alan Modra
2006-10-11 14:08                               ` Alan Modra
2006-10-11 14:19                               ` Jakub Jelinek
2006-10-11 14:45                                 ` Jakub Jelinek
2006-10-12 10:18                                 ` Alan Modra
2006-10-12 14:37                                   ` Alan Modra
2006-10-13 10:58                                   ` Jakub Jelinek
2006-10-13 11:10                                     ` Alan Modra
2006-10-13 11:26                                       ` Alan Modra
2006-10-17 16:02                                   ` Dynamic section symbols, ignored output sections Alan Modra
2006-10-19 14:55                                     ` ligang
2006-10-22  0:25                                     ` Jakub Jelinek
2006-10-23 14:13                                       ` Alan Modra
2006-09-29  6:42                       ` Linker Bug or Design Intent (Absolute symbols in zero sized sections) Alan Modra
2006-09-29  8:06                         ` Alan Modra
2006-09-26 16:14         ` H. J. Lu
2006-09-26 16:40           ` Vivek Goyal
2006-09-26 17:57           ` Vivek Goyal
2006-09-26 20:23             ` H. J. Lu

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=20060926235350.GA4214@nevyn.them.org \
    --to=drow@false.org \
    --cc=binutils@sources.redhat.com \
    --cc=binutils@sourceware.org \
    --cc=hjl@lucon.org \
    --cc=vgoyal@redhat.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).