[gdal-dev] Reason not to enable gdal --with-threads by default?

[Dane Springmeyer]

In the Mapnik library we open a GDALDataset per thread, for each feature query, but have been seeing crashes when rendering large geotiffs.

I've assumed that GDALDataset was fairly threadsafe in recent revisions as per (http://trac.osgeo.org/gdal/wiki/FAQMiscellaneous#IstheGDALlibrarythread-safe), but recently learned that you must force --with-threads during configure to get this working.

Once I rebuilt gdal --with-threads all my troubles went away.

Are there caveats or other reasons not to pass --with-threads during the configure stage. E.g. should is not be made default some time in the future?

Thanks,

Dane