Hi Sergei I cant, but Heinz has managed to (see https://mariadb.atlassian.net/browse/MDEV-6282)
The value of lex at that point is NULL in the core I guess if that situation is impossible by design, this is more likely to be a memory overrun instead... In any case, I got Heinz to try my fix and the crash still happened in the same spot. So I think my next step at this point is valgrind... --A On 02/06/14 20:53, Sergei Golubchik wrote: > Hi, Andrew! > > On Jun 02, Andrew McDonnell wrote: >> Hi all >> >> (Cross-posted to oqgraph-developers, maria-developers) >> >> I am trying to track down a segfault apparently triggered by concurrent >> execution of queries through OQGraph - for context, see: >> >> https://mariadb.atlassian.net/browse/MDEV-6282 >> >> I am however a bit confused as to what is going on, because at least some of >> the information leads me to suspect that there could be more going on here >> than just a simple race condition. >> >> --Immediate Cause-- >> >> On the surface, a segfault appears to be caused in a method in sql_class.h, >> Statement::check_limit_rows_examined() dereferencing a NULL pointer, `lex`. >> The method check_limit_rows_examined() was called from sql_class.h method >> handler::increment_statistics() . > I don't see how thd->lex could be NULL there. It shouldn't be changed > concurrently on anything. > > Can you actually repeat the crash? > > Regards, > Sergei -- Mailing list: https://launchpad.net/~oqgraph-dev Post to : oqgraph-dev@lists.launchpad.net Unsubscribe : https://launchpad.net/~oqgraph-dev More help : https://help.launchpad.net/ListHelp
