Re: test for allocatable function (f95 extension)

[Brooks Moses <bmoses at stanford dot edu>]

Uttam Pawar wrote:
> $ cat test.f90  
>          program no_leak
>              real, dimension(100) :: x, y
>              y(:size(compact(x))) = compact(x)**2
>            contains
>            function compact(x)
>              real,allocatable,dimension(:) :: compact
>              real,dimension(:),intent(in) :: x
>              integer             :: n
>              allocate(compact(n))
>            end function compact
>           end
>
> $ test.f90
> gfortran test.f90
>
>  In file test.f90:6
>
>              real,allocatable,dimension(:) :: compact
>                                                     1
> Error: ALLOCATABLE attribute conflicts with FUNCTION attribute at (1)

Fortran 95 Draft standard, section 5.2.6: "Constraint: The array-name 
[in an ALLOCATABLE statement] shall not be a ... function result."

I can't find where it directly gives the same constraint for ALLOCATABLE 
as an attribute rather than in a statement of its own, but the first 
paragraph of 5.2 says, regarding attribute specification statements: 
"The combination of attributes that may be specified for a particular 
entity is subject to the same restrictions as for type declaration 
statements regardless of the method of specification," which I would 
infer is intended to mean that this constraint applies to the case you 
illustrate as well.

This is, I believe, something added in one of the F95 TRs and in F2003.

- Brooks