Re: flags for different fortran compilers

[Eve-Marie Devaliere]

Thanks Ralph.

> > Which kinds of flags do you need support for?
lots... :(
For example, in their original make.macros they had
# Compiler settings for DEBUG builds
LINUX_COMMON_FLAGS_GFORTRAN_DEBUG = -pg
LINUX_FLAGS_GFORTRAN_DEBUG =
                             "FC_FLAGS= -c \
                                        -fbounds-check \
                                        -fconvert=big-endian \
                                        -ffpe-trap=overflow,zero \
                                        -ffree-form \
                                        -fno-second-underscore \
                                        -frecord-marker=4 \
                                        -ggdb \
                                        -static \
                                        -Wall \
                                        ${INCLUDES} \
                                        ${LINUX_COMMON_FLAGS_GFORTRAN_DEBUG}" \
                         

# Compiler settings for DEBUG builds
LINUX_COMMON_FLAGS_GFORTRAN_PROD =
LINUX_FLAGS_GFORTRAN_PROD =
                            "FC_FLAGS= -c \
                                       -O3 \
                                       -fconvert=big-endian \
                                       -ffast-math \
                                       -ffree-form \
                                       -fno-second-underscore \
                                       -frecord-marker=4 \
                                       -funroll-loops \
                                       -ggdb \
                                       -static \
                                       -Wall \
                                       ${INCLUDES} \
                                        ${LINUX_COMMON_FLAGS_GFORTRAN_PROD}" \
               

I should be able to work with them to figure out what is really needed,
hopefully....

> > The "Autoconf Way" of implementing things, when there isn't a predefined
> > macro for some feature, is to try out a set of known compiler switches
> > and select the first one that has the desired features.  For example,
> > the AC_FC_FREEFORM macro tries to compile a small free-form source file,
> > and passes one of a few known compiler flags that enable free form.  It
> > picks the first one that works.
ok, yes I think I have seen explanations about that... from what I tried
though, if I say
AC_FC_FREEFORM()
nothing happens as far as creating a 'free flag'... I thought it would
find the appropriate one...?
I need to say AC_FC_FREEFORM([],[FCFLAGS="$FCFLAGS -free"]) to add it
but of course that will work for intel compiler but not for others....
DId I miss something?

> > If you can formulate your needs in such a way, then the next hurdle is
> > to overcome the M4 language and a few Autoconf building block macros
> > like AC_COMPILE_IFELSE and AC_LINK_IFELSE.  We can help with the latter
> > if the former is clear.
Thanks. I tried to do a locate to see if I could figure out what is done
for  AC_FC_FREEFORM but I couldn't find it.... would you have an example
to suggest to put me on the way?

Thank you so much for all the help!
Cheers,
Eve-Marie

> > Cheers,
> > Ralf