[postgis-devel] Topology Regression Failure

[Sandro Santilli]

On Wed, Feb 08, 2012 at 09:21:18AM +0100, Sandro Santilli wrote:
> On Wed, Feb 08, 2012 at 09:05:23AM +0100, Sandro Santilli wrote:
> > On Tue, Feb 07, 2012 at 04:32:40PM -0800, Paul Ramsey wrote:
> > > Sandro,
> > > Something in my cleanup to lwgeom_release
> > > (http://trac.osgeo.org/postgis/changeset/9072/trunk) is causing
> > > problems in topology...
> > > 
> > > 
> > > --- regress/st_createtopogeo_expected   2011-11-13 13:55:16.000000000 -0800
> > > +++ /var/folders/vQ/vQpcmrOZEXuINbyg+7Jj4k+++TI/-Tmp-//test_17_out
> > >  2012-02-07 16:29:46.000000000 -0800
> > > @@ -5,16 +5,16 @@
> > >  ERROR:  Geometry SRID (0) does not match topology SRID (4326)
> > >  T1|POINT(0 0)
> > >  T1|1 nodes|0 edges|0 faces
> > > -T2|SRID=4326;LINESTRING(0 0,8 -40)
> > > -T2|2 nodes|1 edges|0 faces
> > > +ERROR:  Invalid edge (no two distinct vertices exist)
> > > +T2|0 nodes|0 edges|0 faces
> > >  T3|SRID=4326;POLYGON((0 0,8 -40,70 34,0 0))
> > >  T3|1 nodes|1 edges|1 faces
> > > 
> > > The problem seems to be in the topology creation, but it doesn't show
> > > up directly and I don't know how to trace through and find out what
> > > *particular* function has changed its behavior. If you can tell me
> > > what function has changed, I can fix it, but at the moment I'm SOL.
> > 
> > Did you check cunit test under valgrind ?
> 
> I just did and it shows a lot of errors in TIN and SURFACE tests,
> but nothing about topology. Will inspect further. May be better
> NOT to cut next alpha until the regression and memory errors are
> fixed.

First error I detect with POSTGIS_TOPOLOGY_DEBUG defined is here:

Good:
 DEBUG:  Split by POINT(36 26): MULTILINESTRING((36 26,38 30))
 DEBUG:  Split by POINT(38 30): MULTILINESTRING((36 26,38 30))

Bad:
 DEBUG:  Split by POINT(36 26): MULTILINESTRING((36 26,38 30))
 DEBUG:  Split by POINT(38 30): MULTILINESTRING((4.94065645841247e-324 6.94094528790257e-310,6.94094528790099e-310 38))

But doesn't look like the problem is in ST_Split, so there must be
some memory corruption before that.

--strk;

  ,------o-. 
  |   __/  |    Thank you for PostGIS-2.0 Topology !
  |  / 2.0 |    http://www.pledgebank.com/postgistopology
  `-o------'