Re: isnan in fortran

[Svante Signell]

On Tue, 2012-04-10 at 14:13 +0100, Michael Goffioul wrote:
> On Tue, Apr 10, 2012 at 2:03 PM, Jordi Gutiérrez Hermoso
...
> > Can Fortran be preprocessed? If so, can we write an autoconf macro to
> > check for isnan and use X.NE.X if not?
> 
> http://gcc.gnu.org/onlinedocs/gfortran/Preprocessing-Options.html
> 
> Apparently, it can be preprocessed, but it's not enabled by default
> for .f files (assuming .f extension is treated differently than .F,
> which is not clear from the documentation).

>From man gcc:

       file.f
       file.for
       file.ftn
Fixed form Fortran source code which should not be preprocessed.

       file.F
       file.FOR
       file.fpp
       file.FPP
       file.FTN
Fixed form Fortran source code which must be preprocessed (with
the traditional preprocessor).