[postgis-users] Crash when creating index on ( int, geom )

[Robin Chauhan]

I eventually discovered that I was meant to attach gdb to the
particular postgres instance, not the postmaster.  However I'm not
sure the bt output is very useful.  Would I need to rebuild postgres
with debug enabled to get anything more meaningful?

(gdb) attach 30603
Attaching to Pid 30603
0x2ac26b22 in ?? ()
(gdb)
(gdb) cont
Continuing.
Program received signal SIGSEGV, Segmentation fault.
0x8082f0f in ?? ()
(gdb) bt
#0  0x8082f0f in ?? ()
#1  0x815fe3f in ?? ()
#2  0x2ae553af in ?? ()
#3  0x81604b5 in ?? ()
#4  0x8071b7c in ?? ()
#5  0x807112f in ?? ()
#6  0x806e574 in ?? ()
#7  0x806e4c6 in ?? ()
#8  0x806e3d6 in ?? ()
#9  0x8160d7c in ?? ()
#10 0x807b4d1 in ?? ()
#11 0x80cfe5d in ?? ()
#12 0x80cc6fc in ?? ()
#13 0x80cc2c3 in ?? ()
#14 0x80cb82d in ?? ()
#15 0x81175b2 in ?? ()
#16 0x8115c67 in ?? ()
#17 0x8116c09 in ?? ()
#18 0x80ff013 in ?? ()
#19 0x80fe8b3 in ?? ()
#20 0x80fdb7d in ?? ()
#21 0x80fd750 in ?? ()
#22 0x80dd93e in ?? ()
#23 0x2ab8c9cb in ?? ()
(gdb) 


On Sat, 29 Jan 2005 17:07:09 -0500, Robin Chauhan
<robin.chauhan at gmail.com> wrote:
> Hello Mark,
> I'm attempting to generate a backtrace as you suggested.  I was able
> to attach gdb to the postmaster process, but I dont know how to make
> gdb break when the failure occurs -- I dont know where I would set a
> breakpoint or watchpoint to be able to catch this event.  When I Can
> you give me a hint or pointer?  I think no core file is being
> generated from the crash, because the postmaster and psql processes
> both continue to run.
> 
> Should I be debugging the psql process and not the postmaster process?
> I tried causing this crashing both while attached to psql and
> postmaster but again I dont know how to cause gdb to stop at a useful
> place to see the backtrace of the crash, and not just of the normal
> running of postmaster.   This is noob territory for me, so please
> excuse the ignorant questions.
> Many thanks,
> -Robin
> 
> On Fri, 21 Jan 2005 17:35:16 -0000, Mark Cave-Ayland
> <m.cave-ayland at webbased.co.uk> wrote:
> > Hi Robin,
> >
> > If you're ok working with source code then I would also compile and use the
> > latest 7.3 release which is currently 7.3.8 with --enable-debug. Create a
> > fresh database cluster with initdb, load your data, and try again. If it
> > still fails then it's fairly certain to be a bug, perhaps something subtle
> > in the PostGIS indexing code or with btree_gist. The backtrace should give
> > us more information on this.
> >
> >
> > Kind regards,
> >
> > Mark.
> >
> > ------------------------
> > WebBased Ltd
> > South West Technology Centre
> > Tamar Science Park
> > Plymouth
> > PL6 8BT
> >
> > T: +44 (0)1752 791021
> > F: +44 (0)1752 791023
> > W: http://www.webbased.co.uk
> >
> >
> > > -----Original Message-----
> > > From: postgis-users-bounces at postgis.refractions.net
> > > [mailto:postgis-users-bounces at postgis.refractions.net] On
> > > Behalf Of Robin Chauhan
> > > Sent: 21 January 2005 17:23
> > > To: Mark Cave-Ayland; PostGIS Users Discussion
> > > Subject: Re: [postgis-users] Crash when creating index on (
> > > int, geom )
> > >
> > >
> > > Mark,
> > >
> > > I tried duplicating the table and got the same reuslt with
> > > the new table.  Thanks for your instructions on getting a
> > > backtrace using gdb.
> > >
> > > Before I tried that, I also attempted to install a more
> > > updated version of btree_gist from here:
> > >
> > > http://www.sai.msu.su/~megera/postgres/gist/btree_gist/btree_g
> > > ist-7.4.tar.gz
> > >
> > > ...which in the README says it can work on postgres 7.3 and
> > > up (I have 7.3.2).  Unfortunately I was not able compile it:
> > >
> > > btree_common.c: In function `gbtreekey_in':
> > > btree_common.c:18: warning: implicit declaration of function `ereport'
> > > btree_common.c:19: warning: implicit declaration of function `errcode'
> > > btree_common.c:19: `ERRCODE_FEATURE_NOT_SUPPORTED' undeclared
> > > (first use in this function)
> > > btree_common.c:19: (Each undeclared identifier is reported only once
> > > btree_common.c:19: for each function it appears in.)
> > > btree_common.c:20: warning: implicit declaration of function `errmsg'
> > > btree_common.c: In function `gbtreekey_out':
> > > btree_common.c:29: `ERRCODE_FEATURE_NOT_SUPPORTED' undeclared
> > > (first use in this function)
> > > make: *** [btree_common.o] Error 1
> > >
> > > For now I am using the separate indexes as suggested by
> > > Markus which is working very well, but I will try to track
> > > this down further.
> > >
> > > -Robin
> >
> >
>