On Mar 14, 2008, at 18:31, Derek Ragona wrote:

At 06:56 PM 3/14/2008, Doug Hardie wrote:
There is no code running at that point.  Its just sitting there
waiting for me to enter a gdb command.


On Mar 14, 2008, at 15:16, Derek Ragona wrote:

At 05:10 PM 3/14/2008, Doug Hardie wrote:
I have a program I was testing with gdb. I was trying to figure out
why c.rmonths was always zero when it should have been 6.  Stepped
through using the gdb n command.  Here is the output:

(gdb)
215                             c.rmonths = (edate - tdate) /
toMONTHS;
(gdb)
223                     c.dial_in = u.dial_in[0];
(gdb)
224                     c.dsl = u.dsl[0];
(gdb) p c.rmonths
$1 = 0
(gdb) p c
$2 = {fa = 0, pwp = 0, disp_email = 0, imonths = 0, rmonths = 6,
  type = 73 'I', cd = 0 '\0', dial_in = 82 'R', dsl = 0 '\0',
dsl_kit = 0 '\0', ip = 0 '\0', domain = 0 '\0', n_domain = 0 '\0',
  renewal = 89 'Y', program = "I\000\000"}
(gdb) p c->rmonths
$3 = 6
(gdb) p c.rmonths
$4 = 6


Notice, the first time i print it its zero.  The second time its 6.
What gives here?  I have seen this before but couldn't pin it down.
The program is not compiled with any optimization. It is in a shared
library though.

It is hard to tell without the code you used.  I would put some
printf's in the code and see what and when that variable gets set to
in actual running code.

        -Derek

I understand it is waiting at a breakpoint in gdb. What I meant was put printf's in your code and run the program and look at the output. You can use fprintf's to stderr if your prefer and just look at the stderr output.

It is hard to diagnose what could be a compiler error, or a coding error. Remember in C you can do many things you really shouldn't. It is also advisable to run lint over your source code too.

All that lint shows is it doesn't like comments using // and lots of errors in /usr/include files.
_______________________________________________
freebsd-questions@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-questions
To unsubscribe, send any mail to "[EMAIL PROTECTED]"

Reply via email to