From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mo DeJong <mdejong@cygnus.com>
To: insight@sources.redhat.com
Subject: Something is very wrong with watchpoints
Date: Thu, 12 Oct 2000 16:23:00 -0000
Message-id: <Pine.SOL.3.91.1001012162239.10110K-100000@cse.cygnus.com>
X-SW-Source: 2000-q4/msg00078.html

I tried to set a hardware watchpoint in insight, it worked but when
I ran the program the GUI stopped responding. It would redraw itself
about once every 5 minutes. Has anyone else run into this?
I am using Linux (Red Hat 6.2) on x86.

Here is a trivial little example that shows how to reproduce
the problem. Just compile this with:

% gcc -g -o watch watch.c

And type the gdb command into the console, note how the GUI
does not redraw after you type continue.

#include <unistd.h>

int main() {
   int i,j;
   for (i=0, j=0; i < 100000000 ; i++) {
     if (i%1000 == 0)
       j++;
   }
}

/*
start the program and set a breakpoint on the for loop line

(gdb) break 5 
(gdb) run

now set a watchpoint at the address of the j variable

(gdb) print &j
(gdb) watch (the hex addr that was just printed)
(gdb) cont

*/

thanks
Mo DeJong
Red Hat Inc