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Re: [RFC/RFA] Add hardware watchpoint support for cygwin target.

At 14:30 28/11/01 -0500, Christopher Faylor wrote:
>On Wed, Nov 28, 2001 at 08:13:12PM +0200, Eli Zaretskii wrote:
>>> Date: Wed, 28 Nov 2001 18:44:44 +0100
>>> From: Pierre Muller <>
>>> But te are some annoying things,
>>> the most annoying is that an exception seems to be generated
>>> on read access of the watched area even if you only set a normal
>>> watchpoint (which should use a write-only debug feature).
>>So you are saying that watch, rwatch, and awatch all yield the same
>>Are you sure that you pass the watchpoint information correctly to
>>the OS?  For example, is the format of DR7 as the OS wants it
>>identical to what GDB uses?  The layout of bits in dr_control_mirror
>>follows Intel documentation, but the OS might want those bits in a
>>different format (that's what the corresponding DPMI call does, for
>>example).  I don't have Windows docs, so I cannot check this.
>>> > /* Get the value of the DR6 debug status register from the inferior.
>>> >    Here we just return the value stored in D_REGS, as we've got it
>>> >    from the last go32_wait call.  */
>>I believe you didn't really mean ``go32_wait'' here ;-)
>I'd like some clarification on this before I can accept the patch.  It
>seems like the described behavior would be annoying indeed.  It would
>be nice to fix this.

As tested and explained in my previous mail, 
the unwanted messages are generated by DLL loading events,
and not by wrong debug register generated stops...

  The behavior of the i386 debug register seems to 
be "normal" (i.e. as the intel docs or Ralph Brwon interrupt list
specifies them).

  The problem is only that the messages should probably be 
removed by disaling output while loading new DLLs.
Does this answer your worries?

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