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Date: Tue, 03 Mar 2009 21:46:00 -0000
From: Daniel Jacobowitz <drow@false.org>
To: Antony KING <antony.king@st.com>
Cc: gdb@sourceware.org
Subject: Re: [GDB 6.8] Problem using watchpoints with compound objects
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References: <49AD6B30.2010102@st.com> <20090303203309.GA2672@caradoc.them.org> <49AD9E8A.3020608@st.com>
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On Tue, Mar 03, 2009 at 09:18:02PM +0000, Antony KING wrote:
> struct {int m1, m2, m3, m4;} a;
> int main (void)
> {
>   a.m1 = 1;
>   return 0;
> }
> 
> In both cases value_equal is comparing the address of the object and not
> the contents. This is caused, I believe, by the following code at the
> start of value_equal:
> 
>   arg1 = coerce_array (arg1);
>   arg2 = coerce_array (arg2);
> 
> which is converting the compound objects into pointers. These are then
> used in the latter tests of value_equal.

Arrays are supposed to be handled specially, but I was talking about
structs since that was in your original example.  coerce_array has no
effect on structs.

-- 
Daniel Jacobowitz
CodeSourcery