! File: acos_test.f90
! Public domain 2005 James Van Buskirk
! gfortran doesn't like the characteristics of acos in
! this example; lf95 5.70f & CVF 6.6C3 do.

module funcs
   implicit none
   contains
      function f(x,g)
         real, intent(in) :: x!(:)
         interface
            elemental function g(x)
               implicit none
               real, intent(in) :: x
               real g
            end function g
         end interface
         real f!(size(x))

         f = g(x)
      end function f
end module funcs

program acos_test
   use funcs
   implicit none
   real x!(5)
   intrinsic acos

   x = 0
   write(*,*) f(x,acos)
end program acos_test