https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65975
Bug ID: 65975
Summary: !$ is not recognized as a comment when -fopenmp flag
is used
Product: gcc
Version: 5.1.0
Status: UNCONFIRMED
Severity: minor
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: CPonder at nVidia dot Com
Target Milestone: ---
I'm working with WRF, the Weather Research Forecasting model.
One of the Fortran files contains these lines
1336 !$ external, logical:: omp_in_parallel
1337 !$ external, integer:: omp_get_thread_num
Evidently the programmer decided to comment-out these declarations by changing
!$OMP --> !$
By my reading of the Fortran standard, this is a legal comment, though I would
much rather have done
!$OMP --> !!$OMP
since it's clearer on what had been commented-out.
Regardless, if I compile the file using the -fopenmp flag, I get the error
!$ external, logical:: omp_in_parallel
1
Error: Invalid character in name at (1)
module_fr_fire_util.orig.F:1337:12:
!$ external, integer:: omp_get_thread_num
1
Error: Invalid character in name at (1)
This error does not happen if I don't use the -fopenmp flag, so it looks like
the parser is insisting on the !$ form denoting a directive whether it is
well-formed or not.
Again, I believe this mal-formed directive is still valid as a comment under
the Fortran standard, and should be treated as such, not triggering an error.
Perhaps a warning would be better?
!$ external, logical:: omp_in_parallel
1
Warning: possible mal-formed OMP or ACC directive at (1)
(if -fopenmp was used, I'd flag it as a possible OMP directive; if -fopenacc
had been used, I would flag it as a possible ACC directive. I both flags are
used, I'd state as above).
As an aside, the PGI compiler doesn't trigger any error here.
Also we're working on changing the WRF source code to clean this up.
