[MITgcm-devel] omp and OMPFLAG

[Martin Losch]

Hi,

I ran across a problem with omp and a cray compiler. Here’s the background:
(1) For a cray compiler, omp is defined by default, except for -O0 (no optimization, which is what we normally use when genmake2 is used with -ieee or when you run testreport (even without -devel).
(2) the order of flags matter, later flags override previous flags.
The consquence is, that if I want to run testreport I cannot use OpenMP, because the order of flags is
$FFLAGS (includes $OMPFLAG) $FOPTION (includes optimization flags): -homp … -O0
The latter will reset -homp to -hnoomp.
I could tweak the build_option file for a cray compiler, but wouldn’t it make more sense to add the OMPFLAG  to FOPTIM in genmake2 (even though it’s stricktly speaking not an optimization flag)?

Martin