Hi folks
I've been contacted by someone to ask about why PostGIS 2.5 or 3.0 rpms aren't produced for RHEL 6 or CentOS 6. They were produced for PostgreSQL 11.
I've done some digging in the repo which suggests that PostGIS 2.5 can't be built for EL-6 due to missing proj49, dependencies in the spec defined against newer geos and proj that cannot be built on EL-6, and dependency on an unavailable gdal version.
I don't see any announcement or detail on this.
Was de-supporting PostGIS on EL-6 an intentional step as part of the Pg12 migration?
I've made changes to build Pg12 / EL-6 / PostGIS 2.5 in my local tree. They're not clean to push as a patch upstream as-is, but I can clean them up if they will be accepted. The only change likely to be controversial is that I need to bring back proj49 (for EL-6 only).
Thoughts?
I've attached the patch, which also contains some unrelated changes to make local builds under Docker easier and provides a wrapper for building. The patch is NOT TO BE MERGED, it's only to help others with this issue.
Details on Pg12/EL-6/PostGIS 2.5 compat:
* PostGIS 3.0 requires C++11 and cannot be built on EL-6 due to
compiler version
* The PostGIS 2.5 spec depends on libgeos 3.8 and proj62
* PostGIS 2.5 can be built successfully against the older proj49 and libgeos 3.6
but the spec doesn't permit that as currently written and we don't build those
dependencies for EL-6 anymore
* libgeos 3.7 and 3.8 require a C++ compiler and cannot be built on EL-6
* proj62 and proj52 require a C++11 compiler and cannot be built on EL-6
* proj49 can be built on EL-6 but has been removed from the repository
by commit caf2197d4 "Remove proj49 and proj52 from repos. No longer needed"
on September 24
* libgeos 3.6 builds on EL-6 but is not built for pg12 - there's no
rpm/redhat/12/geos36/EL-6 symlink, though a
rpm/redhat/11/geos36/EL-6 exists
* postgis 2.5 appears to be enabled for pg11 since
rpm/redhat/11/postgis25/EL-6 exists - but it cannot be built given the
dependencies defined.
I repeat, patch is NOT FOR MERGE.
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