Re: [Valgrind-developers] atexit causes false positives in helgrind&drd; How to intercept exit()?

[Konstantin S. <kon...@gm...>]

I've managed to intercept exit.
http://code.google.com/p/data-race-test/source/detail?r=1176#
You might want to do the same in helgrind/drd.

--kcc

On Tue, Oct 20, 2009 at 6:23 PM, Konstantin Serebryany <
kon...@gm...> wrote:

> Hi,
> I've recently found a false positive in ThreadSanitizer/Helgrind/DRD.
>
> 1. Access a var.
> 2. register atexit callback
> 3. call exit
> 4. in atexit callback access a var
>
>
> http://code.google.com/p/data-race-test/source/browse/trunk/unittest/racecheck_unittest.cc?spec=svn1175&r=1175#6988
>
> ==14652== Possible data race during write of size 4 at 0x63f17c by thread
> #1
> ==14652==    at 0x40390A: test152::AtExitCallback()
> (racecheck_unittest.cc:6994)
> ==14652==    by 0xE120A5E: exit (in /usr/grte/v1/lib64/libc-2.3.6.so)
> ==14652==    by 0xE10AB30: (below main) (in /usr/grte/v1/lib64/
> libc-2.3.6.so)
> ==14652==  This conflicts with a previous write of size 4 by thread #2
> ==14652==    at 0x4150E3: test152::AtExitThread()
> (racecheck_unittest.cc:6998)
> ==14652==    by 0x42469F: MyThread::ThreadBody(MyThread*)
> (thread_wrappers_pthread.h:375)
> ==14652==    by 0xD54A302: mythread_wrapper (hg_intercepts.c:201)
> ==14652==    by 0xD7530C9: start_thread (in /usr/grte/v1/lib64/
> libpthread-2.3.6.so)
> ==14652==    by 0xE1B9811: clone (in /usr/grte/v1/lib64/libc-2.3.6.so)
>
> The simplest way to fix this is to create a h-b arc between atexit() and
> exit().
> I managed to intercept atexit(), but can't do it for exit().
> Is there any dark magic associated with intercepting exit()?
>
> Thanks,
>
> --kcc
>
>
>
>