Re: netcdf packages

[Warren Turkal <wt@atmos.colostate.edu>]

On Tuesday 12 December 2006 19:35, you wrote:
> Regarding the use of gfortran -- are you aware that g77 and gfortran
> produce object code with somewhat incompatible ABIs?  See my previous
> emails on this topic here:

Yes, I am aware. Since there is neither a fortran policy nor a good record of
best practice (different packages use gfortran or g77 randomly. That's why I
mentioned Gfortran so prominently in the changelog.

However, I feel it's also important to mention the following.

wt@oldbraindead:~/tmp$ grep-dctrl -F Build-Depends 'netcdfg-dev' -s 
Package /var/lib/apt/lists/http.us.debian.org_debian_dists_etch_main_source_Sources 
> netcdf_packages.txt
wt@oldbraindead:~/tmp$ grep-dctrl -F Build-Depends 'g77' -s 
Package /var/lib/apt/lists/http.us.debian.org_debian_dists_etch_main_source_Sources 
> g77_packages.txt
wt@oldbraindead:~/tmp$ join -j 2  netcdf_packages.txt g77_packages.txt | wc -l
3
wt@oldbraindead:~/tmp$ join -j 2  netcdf_packages.txt g77_packages.txt | 
awk '{print $1}'
grace
grace6
kst


I think it is safe to say that the g77 bindings of the netcdf library are
only possibly used by those 3 packages.


KST:
wt@oldbraindead:~/src/kst/kst-1.3.1$ find . -name '*.f*' -o -name '*.F*'
./kst/tests/healpix/healpix_example_sm.fits
./configure.files

There's no fortran in kst, it seems.


Grace:
wt@oldbraindead:~/src/grace/grace-5.1.20$ find . -name '*.f*' -o -name '*.F*'
./grace_np/testf_np.f
./examples/logistic.fit

One fortran 77 file.
wt@oldbraindead:~/src/grace/grace-5.1.20$ grep -i nf_ ./grace_np/testf_np.f

NetCDF appears to not be used in Grace as all netcdf APIs begin with nf_
in the f77 binding.


Grace6:
Same story as for grace above. No NetCDF used in fortran77 files.


> Unfortunately it seems that no one is yet endeavoring to make sure there
> is a reasonable transition plan for libraries from g77 to gfortran.
> (Possibly I will try to do something about this post-etch, if I have
> time and once gfortran supports all the g77 intrinsics.)  For that
> reason I recommend that all FORTRAN libraries, when possible, be
> compiled with g77 for the moment.
>
> If netcdf does not have any functions returning REAL (single-precision)
> or COMPLEX, maybe building netcdf with gfortran is OK though.

I don't think that this problem should hold back netcdf as the majority of
modern fortran use of netcdf requires the f90 bindings. G77 does not
include support for f90 and I feel it is a disservice to the scientific
users to not include the f90 support.

I also feel that the results of the above research indicate that there will
be no fallout with packages in the main archive with regard to compiling
the netcdf lib with gfortran.

I think that we should just go for it. W00T!

Comments?

wt
-- 
Warren Turkal, Research Associate III/Systems Administrator
Colorado State University, Dept. of Atmospheric Science