[gdal-dev] OGRCreateCoordinateTransformation problem on GDAL 3.0.3 and PROJ 6.3.0

[Even Rouault]

On jeudi 23 janvier 2020 18:35:40 CET Edzer Pebesma wrote:
> On 1/23/20 5:58 PM, Even Rouault wrote:
> >> Thanks! Yes, with SRS->importFromUserInput("EPSG:3857"); etc this works
> >> fine; I'm OK with the warning, I just don't see how the subsequent error
> >> relates to syntax that is deprecated.
> > 
> > I'm looking at this, but haven't yet an explanation. This is very subtle,
> > and seems to be linked specifically to EPSG:3857

OK, memory helping, I finally identified the root cause. This is a bug in 
PROJ. Fix submitted per https://github.com/OSGeo/PROJ/pull/1873

While being deterministic, it indeed looks like random in practice. I'm not 
even sure the workaround I proposed would work reliably in all situations with 
calls to GDAL/PROJ that would have been attempted before (due to caching of 
objects inside PROJ context). So either wait for a version with
https://github.com/OSGeo/PROJ/pull/1873 applied, or migrate away from use of 
the deprecated +init=epsg:XXXX syntax

Even

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