[PostGIS] #5612: Regression failure with CG_Visibility

[PostGIS]

#5612: Regression failure with CG_Visibility
---------------------+---------------------------
  Reporter:  robe    |      Owner:  lbartoletti
      Type:  defect  |     Status:  new
  Priority:  medium  |  Milestone:  PostGIS 3.5.0
 Component:  sfcgal  |    Version:  master
Resolution:          |   Keywords:
---------------------+---------------------------
Comment (by robe):

 The PG14 second time around failed, so even on the same system, it seems
 unpredictable.
 https://winnie.postgis.net/job/PostGIS_EDB_Regress_winnie/17944/consoleFull


 {{{
 -----------------------------------------------------------------------------
 --- ./sfcgal/regress/visibility_expected        2023-11-15
 01:06:51.527511000 -0500
 +++ /projects/postgis/tmp/3.5.0dev_pg14_geos3.13_gdal3.7.1w64/test_172_out
 2023-11-15 19:50:42.347402200 -0500
 @@ -1,4 +1,4 @@
  Visibility point in polygon|POLYGON((3 2,1 2,0 4,0 0,3 2))
  Visibility point in polygon with hole|POLYGON((0 1.67,0.2 1.8,0.9
 1.8,1.93 1.29,3 2,1 2,0 4,0 1.67))
 -Visibility segment in polygon|POLYGON((1 2,0 4,0 0,4 0,4 4,1 2))
 +Visibility segment in polygon|POLYGON((1 2,4 4,4 0,4 4,2 0,0 4,1 2))
  Visibility segment in polygon with hole|POLYGON((19 -2,12 6,14 14,10.43
 7.57,11 7,11 6,10 6,9.56 6,9 5,1 2,4.67 2.33,8 4,10 3,9.87 2.81,12 3,19
 -2))
 -----------------------------------------------------------------------------
 }}}

 Which is different from the other unexpected answer I got on the failed
 PG16 run and different from the GHA Debian bookworm runs


 {{{
 Expected:            Visibility segment in polygon|POLYGON((1 2,0 4,0 0,4
 0,4 4,1 2))
 Windows PG14 result: Visibility segment in polygon|POLYGON((1 2,4 4,4 0,4
 4,2 0,0 4,1 2))
 Windows PG16 result: Visibility segment in polygon|POLYGON((1 2,4 4,4 0,4
 4,4 0,0 4,1 2))
 GHA PG16     result: Visibility segment in polygon|POLYGON((1 2,0 4,1 0,4
 4,4 0,4 4,1 2))
 }}}
-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/5612#comment:3>
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