FX wrote:
> From a bug filed in the GCC tracking system, I have come to question what
> is the standard-expected behaviour for MAX when it is passed optional
> arguments. For example, please consider the following code:

>   program test
>     print *, m1(1,2,3,4)
>     print *, m1(1,2,3)
>     print *, m1(1,2)
>     print *, m1(1)
>     print *, m1()
>   contains
>     integer function m1(a1,a2,a3,a4)
>       integer, optional :: a1,a2,a3,a4
>       m1 = max(a1,a2,a3,a4)
>     end function m1
>   end

> What is the expected output? The F2003 standard (draft) actually isn't
> very clear about the arguments to MAX, to say the least (or, if it is
> clear, I didn't find the right place).

> My own understanding of how this works is that the first three print
> statements should output 4, 3, 2 and 1 respectively, while the last one
> is actually not valid code. If that reading is true, what do you think of
> the following modified code?

>   program test
>     print *, m1(3,4)
>     print *, m1(3)
>     print *, m1()
>   contains
>     integer function m1(a1,a2)
>       integer, optional :: a1,a2
>       m1 = max(a1, a2, 1, 2)
>     end function m1
>   end

> Should it print 4, 3 and 2? Or is each call to m1() illegal, because the
> standard seems to assume that the first arguments to MAX have a special
> status, and should not be missing?

> Sorry for the long post, and thanks for your light on that question.