Re: [patch] OpenMP: Add -fopenmp-force-usm mode

[Tobias Burnus <tburnus@baylibre.com>]

[-- Attachment #1: Type: text/plain, Size: 881 bytes --]

Jakub Jelinek wrote:
> How is that option different from
> echo '#pragma omp requires unified_shared_memory' > omp-usm.h
> gcc -include omp-usm.h
> ?
> I mean with -include you can add anything you want, not just one particular
> directive, and adding a separate option for each is just weird.

For C/C++, -include seems to be indeed sufficient (albeit not widely 
known). For Fortran, there at two issues: One placement/semantic issue: 
it has to be added per "compilation unit", i.e. to the specification 
part of a module, subprogram or main program. And a practical issue, 
gfortran shows:

error: command-line option '-include !$omp requires' is valid for 
C/C++/ObjC/ObjC++ but not for Fortran

Thus, for Fortran it is still intrinsically useful – even if one can 
argue whether that feature is needed at all / whether it should be added 
as command-line argument.

Tobias