Re: preprocessed F90 using IBM XL F90 compiler

[Dr Magnus Hagdorn]

On Wed, 2006-04-19 at 09:07 -0700, Noah Misch wrote:
> On Wed, Apr 19, 2006 at 09:27:12AM +0100, Dr Magnus Hagdorn wrote:
> > I define symbols using AC_DEFINE which should be passed to the
> > preprocessor to optionally compile certain parts. This all works fine
> > except for when the IBM XL f90 compiler is used. This compiler does not
> > have the -D switch to pass options to the preprocessor and instead
> > expects -WF,-D. I tried to redefine the DEFS macro in the Makefile.am to
> > something like
> > if AIX_XL
> >  DEFS = $(DEFS:-D%=-WF,-D%)
> > endif
> > however make complains about infinite recursion. 
> 
> DEFS references itself; use `DEFS := ...' to avoid this problem.  Note that 
> many
> non-GNU Make programs do not provide pattern substitution references or `:='.
> 
> > Any suggestions on how to solve this problem?
> 
> If portability to a wide variety of Make programs is not a priority, the above
> solution is fine.  Otherwise, try this:
> 
>   if AIX_XL
>     DEFS = `echo @DEFS@ | sed 's/-D[^  ]*/-WF,&/g'`
>   endif
> 
> It does incur a regrettable performance hit.
> 
unfortunately, I get in both cases this error message:
src/Makefile.am:51: DEFS was already defined in condition TRUE, which
includes condition FC_XL ...
configure.in:10: ... `DEFS' previously defined here
which is AM_INIT_AUTOMAKE

looking at the Makefile.in I get
# the IBM compiler needs special flags for the preporcessor, set them
here:
@address@hidden = `echo @DEFS@ | sed 's/-D[^    ]*/-WF,&/g'`
DEFS = @DEFS@

which doesn't look right.

> 
> Ideally, Autoconf should test -D and -WF,-D and use the one that works.  Since
> the C compiler will probably still need -D, we would create a DEFS variable 
> for
> each preprocessed language: CDEFS, CXXDEFS, F77DEFS, FCDEFS.  Automake would
> need changes to take advantage of the new variables, but Autoconf could
> substitute DEFS = ${CDEFS} for backward-compatibility.
> 
yes. grrr, the IBM Fortran XL compiler is just a total pain to support.
Everything is odd.

Cheers
magnus
-- 
Dr Magnus Hagdorn <address@hidden>