autoconf usage : -DHAVE_GSL ?

[Brian Gough]

Peter Teuben writes:
 >  actually, this still didn't work for me !  It still claimed it
 > would not even find main. If i link static (manually done), things
 > look better, but basically, i kept the stupid kludge in until i
 > find something that actually works.

how about,

AC_SEARCH_LIBS(sin, m);
AC_SEARCH_LIBS(cblas_daxpy,gslcblas)
AC_SEARCH_LIBS(gsl_version,gsl)