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Re: Watching complex expressions patch
muller@cerbere.u-strasbg.fr wrote:
>
> At 11:50 04/11/99 -0800, Stan Shebs wrote:
> >
> > Date: Thu, 04 Nov 1999 11:46:19 +0100
> > From: Pierre Muller <muller@cerbere.u-strasbg.fr>
> >
> > So my mecanism remembers the last memory that has been set a watch
> > and after reject all watches of bigger memory regions including that
> memory !
> >
> >I'm not clear on what you're getting at here, but it sounds wrong.
> >GDB should allow the user to set any combination of watchpoints on the
> >same or related pieces of data. The reason is the same as for
> >breakpoints; it's possible to attach conditions to watchpoints, and
> >you may have reason to attach one condition to "watch t.c", but a
> >different condition to a "watch t". GDB should evaluate both
> >conditions whenever t.c changes, but only one condition each time t.a
> >or t.b changes.
>
> No, you misunderstood me :
> I was only talking about a val_clain for one specific watchpoint
> Settings different watchpoint that overlap is not affected by my changes !!
>
> The last memory region is reset to zero
> for each watchpoint considered !
Good, that is encouraging.
Now, how about a complex watch expression, in which
the sub-expressions may define overlapping memory ranges?
To make a crude and artificial example, what about:
watch *a, *b
where a and b point to overlapping regions? Or what about
watch a + a
I know these are contrived, but you get the idea.
An arbitrary expression may legitimately involve
overlapping memory regions. Will your change
affect these?