[vsipl++] patch: enable/disable fftwf, fftw, and fftwl individually

[Jules Bergmann]

Stefan Seefeld wrote:
> Jules,
> 
> thanks for your feedback. Please find attached the relevant part of the 
> patch, somewhat revised:

Overall this looks good, I just have a couple of questions.

> 
> * I moved the definition of 'provide_fft_<type>' to configure.ac to make 
> sure it gets initialized to 0 before any test will set it.

Sounds good.  Looks like an artifact of the configure.ac break-up.


> 
> * I fixed code (in configure.ac) that assumed its default value was '', 
> not '0'.

Why change this?

Since provide_fft_{type} is always 0 or 1, the current behavior defines 
VSIP_IMPL_PROVIDE_FFT_{TYPE} to 0 or 1.  The new behavior defines it to 
1 or leaves it undefined.  This will break existing logic relies on this 
(i.e. '#if VSIP_IMPL_PROVIDE_FFT_{TYPE} && XYZ').

> 
> * I use fftw_has_<type> in my fftw tests, and then propagate any 'on' 
> flags to 'provide_fft_<type>'.

Sound good.

> +if test "$neutral_acconfig" = 'y'; then
> +  if test $fftw_has_float = 1; then
> +    CPPFLAGS="$CPPFLAGS -DVSIP_IMPL_FFTW3_HAVE_FLOAT"
> +  fi

Is this portable?  In particular, since fftw_has_float may not be 
defined, does this create a problem older broken 'sh's?  (I would love 
to get rid of all that "x$foo" cruft in configure, so I hope we do it 
for a reason!)

				-- Jules



-- 
Jules Bergmann
CodeSourcery
jules at codesourcery.com
(650) 331-3385 x705