On Tue, 2012-12-18 at 21:00 +0900, ISHIKAWA,chiaki wrote: > (2012/12/18 8:07), Philippe Waroquiers wrote: > > Destruction of unknown cond var is probably/maybe bug > > https://bugs.kde.org/show_bug.cgi?id=307082 > > > I have produced a patch to take care of the issue. > But before that, I have a question. > > Q1: Why does valgrind not complain if I compile & link > Marc's code (in the bug entry which was given as a reminder that > "unknown cond var" may be a bug or false positive.) in the following manner, > > cc -o /tmp/a.out marc.c No idea. Maybe a problem of redirection caused by static linking ?
> Q2: I have produced a work-in-progress patch to take care this issue. > I wonder if the developers in the know can take a look and improve it. > > The patch is posted to the bug entry > https://bugs.kde.org/show_bug.cgi?id=307082 I took a quick look at the patch, approach looks ok to me. No time to look more in depth at this now however :(. > Not sure, though if it works with the initialized data as in > pthread_mutex_t mut = PTHREAD_MUTEX_INITIALIZER; > pthread_cond_t cond = PTHREAD_COND_INITIALIZER; I assume there is no function call for the above, so no way to have Valgrind knowing that it is ok to destroy cond. > > [Note: No it can't be obviously. This is because the mapping of cond var > to CVInfo structure can not be done explicitly using the timing of > pthread_cond_init(). I tested it to confirm this observation by a slight > modification of marc's code.] > > Q3: > > I have in a corner a patch for helgrind which print symbolic information > > for the lock addresses. Patch not finished yet. > > > > Would be worth filing a wish bug in bugzilla telling that helgrind > > could use --read-var-info=yes to show more info about > > cond var addresses, lock addresses, etc. > > > > Philippe > > You mean helgrind can't use the information obtained by > --read-var-info=yes (!?). That is tough, indeed. helgrind uses --read-var-info=yes to report details about address involved in race condition. It does not use it to describe locks, cond var, etc... For this, might be good to file a wish bug. Philippe ------------------------------------------------------------------------------ LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d _______________________________________________ Valgrind-users mailing list Valgrind-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/valgrind-users
