PostGIS causing PostgreSQL Segfault

[thomersch]

So, I am not entirely sure whether this is a packaging, a linking or a software problem, but maybe someone can have a look and try to understand where this issue is coming from.

• ran brew update and can still reproduce the problem?
• ran brew doctor, fixed all issues and can still reproduce the problem?
• if brew gist-logs didn't work: ran brew config and brew doctor and included their output with your issue?

brew config/brew doctor: https://gist.github.com/thomersch/0a877beed03d39ea28d3f9c011f93f46

What you were trying to do (and why)

You'll need CREATE EXTENSION postgis; CREATE EXTENSION postgis_sfcgal;.

When executing

SELECT ST_StraightSkeleton(
    ST_GeomFromEWKT('SRID=3857;POLYGON((2 1,1 0,0 1,0.999999999999993 2,2 1))')
);

in psql, the PostgreSQL connection process segfaults and the DB has to restart itself. Please note that

SELECT ST_StraightSkeleton(
    ST_GeomFromEWKT('SRID=3857;POLYGON((2 1,1 0,0 1,0.999999999999992 2,2 1))')
);

works absolutely fine. This is not a synthetic issue as it often occurs when using ST_Buffer(), e.g.

SELECT ST_StraightSkeleton(
    ST_Buffer(ST_GeomFromEWKT('SRID=3857;LINESTRING (1 1, 5 5)'), 1)
);

I am running current versions of everything related: PostgreSQL 12.1, Postgis 3.0.0, Geos 3.8.0, SFCGAL 1.3.7, Proj 6.3.0

I was able to reproduce this on a different mac, but not on either Linux or FreeBSD that's why I assume this might have to do something with the packaging/building.

The stacktrace of the crash: https://gist.github.com/thomersch/69f2410242e9962680020da405c691e2

Step-by-step reproduction instructions (by running brew install commands)

brew install postgis
brew services start postgres
createdb foo
psql foo
CREATE EXTENSION postgis; CREATE EXTENSION postgis_sfcgal;
SELECT ST_StraightSkeleton(
    ST_Buffer(ST_GeomFromEWKT('SRID=3857;LINESTRING (1 1, 5 5)'), 1)
);

[fxcoudert]

For the record, the stack trace ends up at:

* thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=EXC_I386_GPFLT)
  * frame #0: 0x000000014f11c7a8 libgmp.10.dylib`mpq_cmp_numden + 113
    frame #1: 0x000000010b184fe3 libSFCGAL.1.dylib`CGAL::CartesianKernelFunctors::Compare_xy_2<CGAL::Simple_cartesian<boost::multiprecision::number<boost::multiprecision::backends::gmp_rational, (boost::multiprecision::expression_template_option)1> > >::operator()(CGAL::Point_2<CGAL::Simple_cartesian<boost::multiprecision::number<boost::multiprecision::backends::gmp_rational, (boost::multiprecision::expression_template_option)1> > > const&, CGAL::Point_2<CGAL::Simple_cartesian<boost::multiprecision::number<boost::multiprecision::backends::gmp_rational, (boost::multiprecision::expression_template_option)1> > > const&) const + 27

Does the issue persist if you run brew reinstall -s gmp and brew reinstall -s sfcgal?

[thomersch]

So I reinstalled gmp and sfcgal from source, restarted postgres, but the same behaviour persists.

[thomersch]

Doesn't look like it's a macOS or homebrew related problem: Oslandia/SFCGAL#202