AC_FC_CHECK_INTRINSICS (function...)
Like AC_CHECK_FUNCS, but instead determine
the intrinsics available to the Fortran compiler. For
each intrinsic in the (whitespace-separated and
case-insensitive) argument list, define
HAVE_INTRINSIC_intrinsic if it is available.
For example, AC_FC_CHECK_INTRINSICS(sin)
would define HAVE_INTRINSIC_SIN if the `sin'
intrinsic function were available (there are probably
rather few Fortrans which don't have this function).
There are some functions, such as getcwd,
getenv and chdir, which are
provided as intrinsics by some Fortran compilers, but
which others supply as external routines in the Fortran
runtime. To deal with this (exasperating)
situation, you need a construction like this in your
configure.ac:
and then conditionalise on the definesAC_FC_CHECK_INTRINSICS([getcwd]) AC_LANG_PUSH([Fortran]) AC_CHECK_FUNCS([getcwd]) AC_LANG_POP([Fortran])
HAVE_GETCWD and
HAVE_INTRINSIC_GETCWD in your preprocessable
code. That is, you use the standard macro
AC_CHECK_FUNCS, but wrapped in declarations
which force the check to use Fortran (this doesn't work in
standard autoconf, since the required support is
missing).