Re: [RFC] Possible bug with i386 watchpoints on several targets.

[Pierre Muller <muller at cerbere dot u-strasbg dot fr>]

At 08:49 05/12/2001 , Eli Zaretskii a écrit:

>On Fri, 30 Nov 2001, I wrote:
>
> > The reason that hardware watchpoints are only considered to fire when
> > the watched value changes is that hardware watchpoints are treated teh
> > same as software watchpoints, and software watchpoints obviously
> > cannot fire unless the watched value changes.
> > 
> > I think it is fundamentally wrong to treat hardware and software
> > watchpoints in a similar way.  I think hardware watchpoints should be
> > treated like read and access watchpoints, not like software
> > watchpoints.  If others (mainly Michael Snyder) agree, I will submit a
> > patch that will make that change, and will also solve this particular
> > problem raised by Pierre.
>
>Michael, did you read this part of my message?  If so, do you agree with 
>the principle?  If you do, I'd like to write a patch that will fix this.

Eli, you didn't answer if you agree that 
the call to i386_cleanup_dregs is required for all targets using
standard i386 hardware watchpoints.

I still think that the linux problem is related to that.
Your bug exists also there but its hidden by the fact
that loading shared libs at startup does set a correct value to
the value of the watched expression at the start of a program.

Which means that adding i386_cleanup_dregs call is not enough
to solve the complete problem, and that your fix is also needed.




Pierre Muller
Institut Charles Sadron
6,rue Boussingault
F 67083 STRASBOURG CEDEX (France)
mailto:muller@ics.u-strasbg.fr
Phone : (33)-3-88-41-40-07  Fax : (33)-3-88-41-40-99