Fortran 90 Presence Of Optional Arguments

Question

I do not understand the behavior of the present() intrinsic function with pgf90 7.2. I wrote a 20 line sample program to test this, but the results still make no sense to m

Answer 1

Are you placing this subroutine in a module and then having a "use" statement for that module in the calling routine (main program or subroutine)? A typical rule is that many of the advanced / new features of Fortran 90 require an explicit interface so that both the caller and callee pass the arguments consistently. The easiest and best way to accomplish this is with module / use. Just a guess...