Updated to Lion recently, I need to install postgis with MacPort. Postgis depends on geos, which I failed to install with the error

:info:build Undefined symbols for architecture x86_64:
:info:build   "__ZNSt8auto_ptrIN4geos4geom8EnvelopeEEcvSt12auto_ptr_refIT_EIS2_EEv", referenced from:
:info:build       virtual thunk to geos::geom::GeometryCollection::computeEnvelopeInternal() constin GeometryCollection.o
:info:build   "std::auto_ptr<geos::geom::envelope>::auto_ptr(std::auto_ptr_ref<geos::geom::envelope>)", referenced from:
:info:build       virtual thunk to geos::geom::GeometryCollection::computeEnvelopeInternal() constin GeometryCollection.o
:info:build ld: symbol(s) not found for architecture x86_64
:info:build collect2: ld returned 1 exit status

It’s said to have been fixed in https://trac.macports.org/ticket/30309, but still failing at latest macport. And the temporary solution mentioned in the ticket doesn’t work either.

sudo port install geos configure.cc=gcc-4.2 configure.cxx=g++-4.2

I got the imperfect way. That is to install geos by non-macport way.

• Download GEOS framework for Snow Leopard/Lion from http://www.kyngchaos.com/software:frameworks#geos, and install it.

• Install proj

    sudo port install proj
  

• Download postgis source code from http://postgis.refractions.net/download/

• Unarchive and install with

    ./configure --prefix=/opt/local --with-geosconfig=/Library/Frameworks/GEOS.framework/unix/bin/geos-config --with-projdir=/opt/local
    make
    sudo make install