[petsc-dev] two quick questions on Fortran style/includes

[Ethan Coon]

On Tue, 2011-05-10 at 18:54 +0200, Jed Brown wrote:
> On Tue, May 10, 2011 at 18:46, Ethan Coon <ecoon at lanl.gov> wrote:
>         Is there a reason that both .F and .F90 examples are in fixed
>         format,
>         even though .F90 files should be interpreted as free format?
> 
> 
> I thought that was up to the compiler flags of the user's project. I
> think the preference is to always write hybrid code in the examples so
> that free/fixed compiler flags don't have to be sorted out at
> configure time and so the user can use whatever convention they like.

Then why are there both .F90 and .F examples (e.g.
src/ksp/ksp/examples/tutorials/{ex1f.F,ex44f.F90}) if both must work in
both formats?

>  
>          I guess
>         the fixed format works for either a fixed/free compiler, but
>         it's ugly.
>         I wouldn't be surprised if there was a portability issue with
>         free
>         format .F90 files, so I figured I'd check.
> 
> There is a Note in the standard showing how to write free/fixed hybrid
> Fortran (non-normative, as pointed out by a gcc developer who didn't
> want to fix the
> warning, http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42852).

-- 
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Ethan Coon
Post-Doctoral Researcher
Applied Mathematics - T-5
Los Alamos National Laboratory
505-665-8289

http://www.ldeo.columbia.edu/~ecoon/
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