postgis2 doesn't work with PostgreSQL 11

[alazarolop]

I have been using PostGIS extension with PostgreSQL 10 from postgis2 formula without issues, but since I've upgraded to PostgreSQL 11, postgis2 doesn't work anymore.

When I try CREATE EXTENSION postgis ; in a new database, I get this message:

ERROR:  could not load library "/usr/local/lib/postgresql/postgis-2.5.so": dlopen(/usr/local/lib/postgresql/postgis-2.5.so, 10): Symbol not found: _AllocSetContextCreate
  Referenced from: /usr/local/lib/postgresql/postgis-2.5.so
  Expected in: /usr/local/opt/postgresql/bin/postgres
 in /usr/local/lib/postgresql/postgis-2.5.so

I've just installed PostgreSQL (11.1) and postgis2 (2.5.1_1) in a clean VM to test it and I get the same result. postgis (2.5.0_1) formula instead works flawlessly, which I tested by linking and unlinking both formulae, postgis and postgis2. All the rest packages from OSGeo4Mac are up to date.

[fjperini]

@alazarolop I think the problem is that you have installed the two versions postgis2/postgis. By uninstalling or unlinking one of the two, you may be deleting /usr/local/lib/postgresql/postgis-2.5.so. Or maybe just seea necessary rebuild for the new PostgreSQL version.

Try only with postgis2 installed, but from source: brew install -build-from-source postgis2

[alazarolop]

I did uninstall postgis and then build from source postgis2. It works like a charm! Thank you.
I take note for the future to avoid installing again postgis.

[fjperini]

@nickrobison We could rename the formula, but this could bring this problem in the others: for example #503:

Error: Formulae found in multiple taps: 
       * brewsci/science/hdf4
       * osgeo/osgeo4mac/hdf4
Please use the fully-qualified name e.g. brewsci/science/hdf4 to refer the formula.

@alazarolop You can close this issue Thanks for informing us about the problem.

[nickrobison]

Thanks for reporting this! It sounds like the bottle needs to be rebuilt, which I can do now.

If homebrew core has an updated version of postgis, do we need to support our own?

I think the best, short term, solution is to make postgis2 keg-only and then link when we specifically need it.

[alazarolop]

@nickrobison would postgis core formula cause incompatibilities as it uses another GDAL package and version (2.3.x) and it's updated with a slower pace?

[fjperini]

@nickrobison @alazarolop That's right, use gdal. I think that was the reason why @PeterPetrik added postgis to osgeo4mac. Also updated much slower.

p/d: I added some more things to the formula. We remember to rebuild the bottle if a new version of PostgreSQL is published.

[nickrobison]

@alazarolop you’re correct, I hadn’t looked at the formula in a while and forgot why it was there! Glad it’s working for you and we’ll address the issues you reported.