From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Cagney <ac131313@cygnus.com>
To: Mark Kettenis <kettenis@science.uva.nl>
Cc: eliz@is.elta.co.il, msnyder@cygnus.com, gdb-patches@sources.redhat.com
Subject: Re: [PATCH]: Make Linux use the new unified x86 watchpoint support
Date: Tue, 27 Mar 2001 10:03:00 -0000
Message-id: <3AC0D5D9.1D61585A@cygnus.com>
References: <Pine.SUN.3.91.1010327085422.19916E-100000@is> <200103270911.f2R9BX421793@debye.wins.uva.nl>
X-SW-Source: 2001-03/msg00505.html

Mark Kettenis wrote:
> 
>    Date: Tue, 27 Mar 2001 08:55:00 +0200 (IST)
>    From: Eli Zaretskii <eliz@is.elta.co.il>
> 
>    On Mon, 26 Mar 2001, Michael Snyder wrote:
> 
>    > Guys, this implementation has problems.  You have it hard-coded
>    > so that on a linux host, it unconditionally calls native linux
>    > methods involving ptrace to get the debug registers.  This breaks
>    > very badly if you're using a native linux host to debug a remote
>    > i386 target.
> 
> Just like the old implementation.  I suspect the old implementation
> just happened to work because it didn't do any strict error checking.
> 
> The fundamental problem is that the watpoint-stuff isn't part of the
> target vector.

I think it is a combination of both the architecture and the target
vector.  It is the same problem as software single step.  A layer of the
target is asked to implement a memory watch.  Since that can't be
implemented directly, it asks the architecture vector to implement it
for it.

	Andrew