Re: gdb doesn't work very well with dynamic linked binaries

[James Cownie <jcownie@etnus.com>]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 2606 bytes --]

This threads seems really to have morphed to be about using the
hardware watchpoint registers on IA32.

So :-

Note that there are a couple of linux kernel bugs in 2.2 (one of which
was fixed in 2.2.17) which affect the use of the debug registers.

The first bug (which was fixed in 2.2.17) was that the debug status
register wasn't being saved where it could be seen by ptrace, so if
you were relying on looking at the hardware status register you were
stuffed.

The second (which isn't yet fixed) I described with a test case in a
previous mail here. ( http://sources.redhat.com/ml/gdb/2000-08/msg00072.html )
Basically the kernel ignores all hardware
watchpoints from the point where one of them is triggered inside the
kernel until a reschedule. This means many watchpoints at user level
can be silently skipped :-(

AFAICS both bugs remain in 2.4.0-test7.

-- Jim 

James Cownie	<jcownie@etnus.com>
Etnus, LLC.     +44 117 9071438
http://www.etnus.com



-- 
-- Jim
James Cownie
jcownie@etnus.com
Etnus, Inc.
Phone +44 117 9071438
From mdeans@algonet.se Wed Sep 06 04:13:00 2000
From: "Bjorn Eriksson" <mdeans@algonet.se>
To: "Russ.Shaw" <russell@webaxs.net>, "Michael Sokolov" <msokolov@ivan.Harhan.ORG>
Cc: <binutils@sources.redhat.com>, <crossgcc@sources.redhat.com>, <gcc@gcc.gnu.org>, <gdb@sources.redhat.com>
Subject: comp.gnu.embedded (was: embedded An article about the Cygnus tree)
Date: Wed, 06 Sep 2000 04:13:00 -0000
Message-id: <000001c017f3$5c69c020$0800a8c0@win95.inteloop.se>
References: <39B57E79.EADD4317@webaxs.net>
X-SW-Source: 2000-09/msg00059.html
Content-length: 1007

> > > I think there should be a newsgroup for the gnu tools etc,
> > > for applications involving embedded systems. comp.arch.embedded
> > > is more hardware oriented.
> > > What about a comp.gnu.embedded for all questions on
> > > installation, development, use, and abuse of gnu/cygnus/open-source
> > > tools for embedded systems?
> >
> > How is the crossgcc mailing list not enough for you for this
> > purpose? That's exactly what it's for.
>
> Its just that crossgcc traffic seems a bit on the low side
> for some reason. BTW, is all this cross-posting bad? A
> newsgroup is better suited for a wide range of questions
> and seems more 'publicly accessible' for beginners to
> ask all kinds of stupid questions.

 I hope you haven't missed linux-embedded@waste.org. I'd also like to see a
comp.gnu.embedded newsgroup but not for the reason you stated. I like to
think we're all trying to help out anyone who spends time and effort to
research his problem and write coherent questions.


//Björnen.