Re: watchpoint troubles

[Paul Koning <pkoning@equallogic.com>]

>>>>> "Mark" == Mark Salter <msalter@redhat.com> writes:

>>>>> Paul Koning writes:
 >> I'm having all sorts of watchpoint troubles with gdb 5.3 and a
 >> remote target.  These are things I'm running into as I'm working
 >> to improve the implementation of watchpoints in my remote stub.

 Mark> ...

 >> Without that flag, the first thing that gdb does after the
 >> watchpoint entry is to read the address being watched.  Needless
 >> to say, that causes a watchpoint recursion within the target stub.
 >> In the case where HAVE_NONSTEPPABLE_WATCHPOINT is defined, things
 >> work because the watchpoint is removed before the memory read
 >> request is made.

 >> Since gdb normally removes and reinserts watch/break points on
 >> every entry, I figured it's gdb's job to do things in the right
 >> order.  Bad assumption?  I can certainly hack up the stub to
 >> remove the watchpoints before acting on any memory access requests
 >> from gdb, but is that kind of hackery supposed to be done?

 Mark> This has come up before:

 Mark> http://sources.redhat.com/ml/gdb-patches/2001-03/msg00506.html

 Mark> I think the answer is that the stub should disable watchpoints
 Mark> anytime the target stops and reenable them when stepping or
 Mark> continuing.

Thanks.  

I just read that thread and the final message seems to say "gdb can be
fixed to remove the watchpoints before doing the memory read in the
case where HAVE_NONSTEPPABLE_WATCHPOINT is undefined.  Yes, I thought
so.

I may do that just to try it.  As I mentioned, what I *really* want is
for the case where HAVE_NONSTEPPABLE_WATCHPOINT *is* defined to work
correctly.  Right now it doesn't.

    paul