by Nick Engdahl
By now you've probably upgraded your Mac to OS X El Capitan (version 10.11) and if you had a previous installation of ParFlow on OS X Yosemite on your system, it's probably working just fine. The reason is that, unlike some previous OS X updates, very little has changed under the hood between the two most recent releases that would have any effect on ParFlow. So to make this arguably the shortest blog post of all time, if you're trying to get a new installation set up on El Capitan the instructions for OS X Yosemite are all you'll need:
OS X Yosemite instructions
But before you click over there, we have come across a very important compatibility issue with Hypre you need to know about. The most recent version (2.10) has changed some function calls and is not compatible with the current ParFlow release. Fortunately, the Hypre developers leave most of their versions available for download so be sure to use Hypre release 2.9.0b or the ParFlow installation will fail.
All of the other components have been tested and we can report that GCC version 6.0, Silo version 4.10.2, and OpenMPI 1.10.2 all work, it's just Hypre that is being difficult. We're looking into an efficient solution but for now, just stick with the legacy version and you'll be fine. And one last reminder, you may and/or probably will need to reinstall command line tools, but that's a mere "xcode-select --install" away (entered at the command line of course).
See, I told you it would be the shortest post ever.