[postgis-tickets] [PostGIS] #2257: totally non-sensical regress failure with empty tickets.sql

[PostGIS]

#2257: totally non-sensical regress failure with empty tickets.sql
-------------------------+--------------------------------------------------
 Reporter:  robe         |       Owner:  robe         
     Type:  defect       |      Status:  new          
 Priority:  medium       |   Milestone:  PostGIS 2.1.0
Component:  postgis      |     Version:  trunk        
 Keywords:  mingw64-w32  |  
-------------------------+--------------------------------------------------

Comment(by dustymugs):

 I think this might be a compound issue.  In looking at the code for
 lwgeom_eq() in postgis/lwgeom_btree.c, it is failing on the second if/else
 evaluation around line #195.  Both input geometries result in the
 variables empty1 and empty2 being TRUE.

 The problem is that the second test compares the coordinates for the
 boxes, which are uninitialized (so says valgrind when running in Linux
 64-bit)...

 Adding some additional debug output...
 {{{
 POSTGIS_DEBUGF(3, "empty1, empty2 = %d, %d", empty1, empty2);
 POSTGIS_DEBUGF(4, "%f ~ %f, %f ~ %f, %f ~ %f, %f ~ %f",
         box1.xmin, box2.xmin, box1.ymin, box2.ymin, box1.xmax, box2.xmax,
 box1.ymax, box2.ymax);
 }}}

 results in...

 {{{
 NOTICE:  [lwgeom_btree.c:lwgeom_eq:189] empty1, empty2 = 1, 1
 NOTICE:  [lwgeom_btree.c:lwgeom_eq:191] 0.000000 ~ 0.000000, 0.000000 ~
 0.000000
 , 0.000000 ~ 1.#INF00, 0.000000 ~ 0.000000
  ?column?
 ----------
  f
 (1 row)
 }}}

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/2257#comment:5>
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