Proliferation of preprocessor directives due to bug in Intel compiler fixed in latest versions?

[climbfuji]

There is a proliferation of preprocessor directives around Open MP pragmas in the code, for example:

GFDL_atmos_cubed_sphere/model/fv_dynamics.F90

Line 418 in d6bfc15

#ifdef __GFORTRAN__

The problem is that the Intel compiler incorrectly required listing pointers in OpenMP shared or private clauses when the default is none. The GNU compiler on the other does not allow listing pointers as shared or private. A discussion with Intel and GNU developers led to the conclusion that GNU was right and Intel was wrong. According to Intel, this was fixed in compiler version 2021.2.

We need to test if this is indeed the case and if decide whether/when we want to to stop supporting older versions of the compiler (at least with OpenMP enabled).

[bensonr]

@climbfuji - should we get this fixed and/or are we onto compiler version support in the UFS that allows this preprocessor macro to be eliminated?

[climbfuji]

I don't think all of the systems are at 2021.2 yet. From https://spack-stack.readthedocs.io/en/latest/PreConfiguredSites.html#pre-configured-sites-tier-1, I see that Cheyenne is still on intel/19.1.1.217, but this system will be decommissioned end of the year.

It would be good to confirm with EMC/NCO (@AlexanderRichert-NOAA and @Hang-Lei-NOAA) that the compiler used on WCOSS2 is at least 2021.2.0 (acorn is 2022.0.2, but it also has a config entry for intel 19).

If we eliminate the macro, we basically remove support for Intel compilers older than 2021.2.0 (maybe we can still compile w/p openmp for older versions, not sure).