From: Daniel Jacobowitz <drow@false.org>
To: Eli Zaretskii <eliz@gnu.org>
Cc: Wu Zhou <woodzltc@cn.ibm.com>, gdb-patches@sourceware.org
Subject: Re: [ppc-linux-nat]: set access flag for h/w watchpoint even if it is only read or write
Date: Thu, 06 Jul 2006 21:37:00 -0000 [thread overview]
Message-ID: <20060706213659.GA985@nevyn.them.org> (raw)
In-Reply-To: <ulkr6qwkt.fsf@gnu.org>
On Thu, Jul 06, 2006 at 11:58:58PM +0300, Eli Zaretskii wrote:
> Yes, this problem is known on x86 and elsewhere. The problem is
> extremely rare, as reading and writing to the same address in the same
> instruction is a hard-to-accomplish treat. Wu, could you show a
> real-life example of where this matters?
I thought, though I may be misremembering, that it was actually a
different problem. Something like this:
- We set a read watchpoint. It does not trigger on writes.
- An instruction writes to the location.
- GDB stops, sees that it stopped at a watchpoint at the given address,
tries to determine what sort of watchpoint it was, determines that
the value had changed, and ignores the read watchpoint - the value
has changed since we last checked so this "must" have been a write
watchpoint.
Is that plausible or nonsensical?
--
Daniel Jacobowitz
CodeSourcery
next prev parent reply other threads:[~2006-07-06 21:37 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-06-09 15:40 Wu Zhou
2006-06-23 0:44 ` [RFC]: h/w watchpoint (r,w,a) for ppc440 Wu Zhou
2006-07-06 13:20 ` [ppc-linux-nat]: set access flag for h/w watchpoint even if it is only read or write Daniel Jacobowitz
2006-07-06 20:59 ` Eli Zaretskii
2006-07-06 21:37 ` Daniel Jacobowitz [this message]
2006-07-07 4:35 Wu Zhou
2006-07-07 10:04 ` Eli Zaretskii
2006-07-07 13:18 ` Daniel Jacobowitz
2006-07-07 15:08 ` Eli Zaretskii
2006-07-08 19:36 ` Ulrich Weigand
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