[J3] Is this standard-conforming?

[Bill Long]

Hi Damian,

I’m guessing that this program does compile :

program main
  implicit none
 
  type ugg  
    integer :: n
  end type ugg

  interface 
    type(ugg) function foo()
       import ugg
    end function foo
  end interface

end  program

Similar to your case, the import of ugg  from the host occurs on the statement after the one where ugg is used.  In the case of a type definition like this there is no practical alternative, so compilers have been taught to ‘look ahead’ for a type definition.   I suspect we intended to allow the case you described, but the vendors did not anticipate needing to do a look-ahead for anything other that the function type.   If Malcolm disagrees about the intent, I’m ok with that.   I think it boils down to whether the FUNCTION statement itself is part of the scoping unit of the function. 

Cheers,
Bill


> On Jul 26, 2018, at 5:12 AM, Damian Rouson via J3 <j3 at mailman.j3-fortran.org> wrote:
> 
> One processor accepts the code below.  Three others generate error messages related to the binding label c_name and either report a syntax error or report that the binding label is a variable that does not reduce to a constant expression.  
> 
> Damian 
> 
> program main
>   implicit none
> 
>   character(len=5), parameter :: c_name="c_foo"
> 
>   interface
>     subroutine foo() bind(C,name=c_name)
>       import c_name
>     end subroutine
>   end interface
> 
>   call foo()
> 
> end  program
> 

Bill Long                                                                       longb at cray.com
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Bioinformatics Software Development                      fax:  651-605-9143
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