This is the mail archive of the cygwin mailing list for the Cygwin project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [gdb] Data watchpoints in Windows weirdness. Call for testers.


Christopher Faylor escreveu:
On Mon, Oct 08, 2007 at 02:43:31PM +0200, Corinna Vinschen wrote:
On Oct 3 01:47, Pedro Alves wrote:
By a long shot, Cygwin doesn't do anything funny like hooking
GetThreadContext, does it?
cgf might be better suited to answer this, but AFAICS, Cygwin
doesn't hook any system function.  It just uses them.

Cygwin doesn't hook GetThreadContext or any other system call. It does play with the threads stack frame when the thread is first created however.

OTOH, there are two calls to SetThreadContext in Cygwin, both of them
changing Eip.  Could that be a problem?

Those should only be triggered in circumstances where a cygwin program is interrupted outside of the cygwin dll itself.


Thanks guys. I would imagine that to make a difference the GetThreadContext in the context of gdb itself would have to be hooked.

Any change someone does the little testing to make sure I'm not
having a local problem here?

as easy as:

gcc main.c -o main.exe -g3 -O0
gdb main.exe
start
watch count
'continue' several times, and send me or post here the results.

A log with the these on would be nice, but not essencial:
set debug infrun 1
set debugevents 1
set debugexceptions 1
maint show-debug-regs 1

Cheers,
Pedro Alves
#include <stdio.h>
#include <windows.h>

volatile int count = 0;

int
main ()
{
  printf ("count %d\n", count);
  count = 999;
  printf ("count %d\n", count);
  count++;

  while (1)
    {
      printf ("count %d\n", count);
      count++;
      Sleep (1000);
    }

  return 0;
}










--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]