[postgis-tickets] [PostGIS] #4990: getfacecontainingpoint fails on i386

[PostGIS]

#4990: getfacecontainingpoint fails on i386
-----------------------------+---------------------------
  Reporter:  Bas Couwenberg  |      Owner:  strk
      Type:  defect          |     Status:  new
  Priority:  medium          |  Milestone:  PostGIS 3.2.0
 Component:  topology        |    Version:  master
Resolution:                  |   Keywords:
-----------------------------+---------------------------

Comment (by strk):

 Ok something is definitely fishy here. Adding a debug line in ptarray.c
 changes results so that the closest segment is reported as being 0 instead
 of 1. With just this patch:
 {{{
 diff --git a/liblwgeom/ptarray.c b/liblwgeom/ptarray.c
 index 7994d60dd..fe23282ea 100644
 --- a/liblwgeom/ptarray.c
 +++ b/liblwgeom/ptarray.c
 @@ -29,7 +29,7 @@
  #include <stdlib.h>

  #include "../postgis_config.h"
 -/*#define POSTGIS_DEBUG_LEVEL 4*/
 +#define POSTGIS_DEBUG_LEVEL 4
  #include "liblwgeom_internal.h"
  #include "lwgeom_log.h"

 @@ -1308,6 +1308,7 @@ ptarray_closest_segment_2d(const POINTARRAY *pa,
 const POINT2D *qp, double *dist
                 double dist_sqr;
                 end = getPoint2d_cp(pa, t);
                 dist_sqr = distance2d_sqr_pt_seg(qp, start, end);
 +               LWDEBUGF(3, "Sqr distance from seg %d: %g", t-1,
 dist_sqr);

                 if (dist_sqr < mindist)
                 {
 }}}

 I guess it's time to valgrind the liblwgeom side of this

-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/4990#comment:25>
PostGIS <http://trac.osgeo.org/postgis/>
The PostGIS Trac is used for bug, enhancement & task tracking, a user and developer wiki, and a view into the subversion code repository of PostGIS project.