Re: [patch, libgfortran RFC] Installation script for OpenCoarrays to enable multi-image gfortran

[Jerry DeLisle <jvdelisle@charter.net>]

On 01/26/2017 05:25 AM, FX wrote:
> Hi Jerry,
> 
> A few questions:
> 
>   - why mpich? doesn’t opencoarrays support any MPI implementation?

We picked it as one that I had available and only as a starting point, we plan
to add support for other libraries as we go. (OpenCoarrays itself does support
other libraries)

>   - I am a bit surprised by the complexity of the script… couldn’t we provide a Makefile for opencoarrays, to be compatible with our other build requirements?

I agree, this script is using Boiler Plate which allows a lot of flexibility and
provides some diagnostics and handling of script errors. It builds on things the
OpenCoarrays team is familiar with and was the quickest way to go initially. My
first draft script was about 50 lines with comments, but it had no error checks.
I will be able to reduce what you see when I narrow down to one tracked release
package.

>   - do we want to work towards seamless implementation of coarrays into gfortran, or coexistence as a separate package (as is currently the case, for example in Mac Homebrew, where it ships as a separate — but compatible — package)?

I think we do want to head toward seamless. I have explored even copying the
source directly into the caf directory of libgfortran and merging the .h files,
but this takes some time to do and would leave two sets of sources to maintain.
Regarding things like Homebrew, or rpm packages, it will require us to learn how
to do these packages which none of us know right now.

Ultimately, since multi images is part of the Fortran language, it should just
happen transparently with the gcc regular build process.

Jerry