[PROJ] Odd 6.3.0RC1 issue

[Even Rouault]

> Speculation, does using SetAxisMappingStrategy(OAMS_TRADITIONAL_GIS_ORDER)
> make a difference?

No, this is only used by GDAL for coordinate reprojection. No impact normally 
on PROJ4 string export

> Anyway, rgdal is definitely broken with 6.3.0RC1 with no +ellps=airy term,
> and no +units=m term after exportToProj4(). What is the name of +ellps to
> use with GDALs OGRSpatialReference GetAttrValue()? 

You can't. GetAttrValue() is about asking value of WKT(1) nodes, of PROJ.4 
string

I suggest that you try to do a minimal .c/.cpp reproducer using only GDAL API 
to identify if the issue is in GDAL/PROJ or in your code.

Even

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