coarray on macOS

[tinkham__douglas]

I've been debating starting a program in C++ or fortran and decided to give 'modern' fortran a spin because I find the language so intuitive and modern fortran looks like it has a lot to offer. I work on a Mac.

While reading the user guide for 18.0, I see on page 2362 that it says "Coarrays are not supported on macOS* systems." Is this actually true or is it possible the guide was not updated here? Elsewhere I read that the fortran 2008 standard/language is now fully supported by Intel Fortran, yet I am fairly certain that coarray is in fact specified in the fortran 2008 standard. 

If they are not supported on macOS, can we expect an implementation before my annual support contract runs out in 11.5 months? I see posts from many years ago indicating there is a problem with Intel's MPI implementation on macOS. 

[DataScientist]

I have had this problem with Intel ifort in the past, and it still exist as far as I know. As an alternative, you could possibly use gfortran's OpenCoarrays implementation. In particular, gfortran's implementation now provides partial support for Coarray Teams, which is indeed a really cool feature added to Fortran in 2018 Standard. From the discussions on Github's page for gfortran Coarray, I remember there was a bug for its usage on Mac OS, which might be already resolved (or not).

OpenCoarrays: https://github.com/sourceryinstitute/OpenCoarrays

Gfortran 8: https://gcc.gnu.org/wiki/GFortran/News#gfortran_8